Enhancing the Quality of Low-Salt Silver Carp (Hypophthalmichthys molitrix) Surimi Gel Using Psyllium Husk Powder: An Orthogonal Experimental Approach

Low-salt surimi production is crucial as it addresses health concerns related to sodium intake while maintaining the quality and shelf-life of seafood products. This research focused on optimizing the gelation conditions for silver carp surimi with the addition of psyllium husk powder at low salt concentrations (0.5% and 1%, w/w) to investigate the effects of psyllium husk powder concentration, temperature, and time on gel strength and water-holding capacity. The quality was assessed in terms of gel strength and water-holding capacity. Following a single-factor exploration, a three-level orthogonal experiment was designed to evaluate the influence of these three variables using a combined scoring system. Results indicated that psyllium husk powder levels between 0.1% and 0.3% (w/w) enhanced gel strength and water-holding capacity. The optimal conditions were identified as follows: 1% (w/w) NaCl with 0.2% (w/w) psyllium husk powder for 2.5 h at 35 °C, and 0.5% (w/w) NaCl with 0.3% (w/w) psyllium husk powder for 3 h at 35 °C. Texture profile analysis revealed that psyllium husk powder increased the hardness of the surimi gel, promoting myosin cross-linking and denser gel structure. Compared to traditional surimi gel, which relies on ionic bonds, the optimized gel showed higher levels of disulfide cross-linking and enhanced hydrophobic interactions, resulting in a stronger gel structure. Sensory evaluation suggested that surimi gels with psyllium husk powder were perceived as better than those without psyllium husk powder. The study concludes that selecting the appropriate psyllium husk powder quantity and thermal processing conditions based on salt concentration can significantly improve the quality of low-salt surimi gels. Error analysis using one-way ANOVA was performed on all experimental data and (p < 0.05) indicated the significant difference.

Preparation and Performance Study of High-Strength and Corrosion-Resistant Cement-Based Materials Applied in Coastal Acid Rain Areas

Investigations regarding the preparation and durability of cement-based materials applied in specific coastal acid rain environments are scarce, particularly those involving the addition of four auxiliary cementitious materials (ACMs) to cement for modification. To improve the durability of concrete structures in coastal acid rain areas, a systematic study was conducted regarding the preparation of high-strength and corrosion-resistant cement-based materials using ACM systems composed of fly ash (FA), granulated blast furnace slag (GBFS), silica fume (SF), and desulfurization gypsum (DG) instead of partial cement. Through an orthogonal experimental design, the effect of the water-binder ratio, cementitious ratio, and replacement cement ratio on the compressive strength, corrosion resistance coefficient, and chloride ion permeability coefficient of the materials were analyzed and the mix proportions of the materials were evaluated and optimized using the comprehensive scoring method. The results show that implementing a FA:GBFS:SF:DG ratio of 2:6:1:1 to replace 60% of cement allows the consumption of calcium hydroxide crystals generated through cement hydration, promotes the formation of ettringite, optimizes the pore structures of cementitious materials, and improves the compressive strength, acid corrosion resistance, and chloride ion permeability of the materials. This study provides a reference for selecting concrete materials for buildings in coastal acid rain environments.

Structural design of gradient porous dental implant based on orthogonal test

OBJECTIVES

To solve the current problems of loosening and dislodging caused by the high elastic modulus of solid implants, we attempted to study a gradient porous dental implant that can lower the stress concentration and reduce the elastic modulus.

METHODS

SolidWorks software was utilized to design the abutment and mechanical structure of the gradient porous implant. The mechanical properties of the gradient porous implant were evaluated by an orthogonal experimental design from four aspects: pore shape, pore diameter, porous layer height, and circumferential distribution. ANSYS software was used to evaluate the distribution of Von-Mises stress in the implant and its surrounding bone tissues under different structural combination parameters to derive the optimal combination of gradient porous implant parameters.

RESULTS

The effects of the four factors, namely, pore shape, pore diameter, porous layer height and pore distribution, on the maximum Von-Mises stress on the implant were as follows. As the pore shape became smaller and the circumferential distribution decreased, the Von-Mises stress decreased significantly. The pore diameter went from 500 μm to 600 μm and then to 700 μm. The Von-Mises stress decreased and then increased. It increased with the increase in the height of the porous layer.

CONCLUSIONS

The final optimal combination of parameters for the gradient porous implant was as follows: square pore shape, pore diameter of 600 μm, porous layer height of 3 mm, and quadratic step in pore distribution.

Insights into the Effects of Co-Regulated Factors on Li1.3Al0.3Ti1.7(PO4)3 Solid Electrolyte Preparation: Sources, Calcination Temperatures, and Sintering Temperatures

The ionic conductivity, phase components, and microstructures of LATP depend on its synthesis process. However, their relative importance and their interactions with synthesis process parameters (such as source materials, calcination temperature, and sintering temperature) remain unclear. In this work, different source materials were used to prepare LATP via the solid-state reaction method under different calcination and sintering temperatures, and an analysis via orthogonal experiments and machine learning was used to systematically study the effects of the process parameters. Sintering temperatures had the greatest effect on the total ionic conductivity of LATP pellets, followed by the sources and calcination temperatures. Sources, as the foundational factors, directly determine the composition of a major secondary phase of LATP pellets, which influences the whole process. The calcination temperature had limited impact on the ion conductivity of LATP pellets if pellets were sintered under the optimal temperature. The sintering temperature is the most important factor that influences the ion conductivity by eliminating most secondary phases and altering the microstructure of LATP, including the intergranular contact, grain size, relative densities, etc. This work offers a novel perspective to comprehend the synthesis of solid-state electrolytes beyond LATP.

Preparation of the Levo-Tetrahydropalmatine Liposome Gel and Its Transdermal Study

Purpose

The aim of this study was to develop a liposome gel containing levo-tetrahydropalmatine (l-THP) and evaluate its transdermal properties.

Methods

A L16 (43) orthogonal experiment was conducted to optimize the preparation of l-THP liposomes and assess their characterization and stability in a gel. The transdermal features were analyzed through in vivo and in vitro experiments on rats and Strat-M® membrane, respectively. The metabolism of l-THP in liver and skin S9 fractions was also studied.

Results

The optimization of the orthogonal experiment revealed that the ideal mass ratio of phosphatidylcholine, cholesterol, and l-THP during preparation was 10:1:3. The resulting liposome exhibited a particle size of 68 nm, a PDI of 0.27, a drug loading of 4.33%, an encapsulation of 18.79%, and a zeta potential of -41.27 mV. Both the l-THP and its liposome-gel formulation were found to be stable for a duration of 45 days at 4 °C and 30 °C. During the in vivo transdermal study, the maximum concentration (Cmax) of l-THP from the liposome gel was 0.16 μg/mL, and the time to reach this maximum concentration (tmax) was 1.2 hours. The relative bioavailability of l-THP in the liposome gel was 233.8% compared to the emulsion. The concentration of l-THP (prepared in PBS) decreased at a rate of 0.0067 μg/mL/min in the liver S9 fraction and 0.0027 μg/mL/min in the skin S9 fraction, however, this difference was not observed when l-THP was encapsulated in liposomes. l-THP passed through the Strat-M® membrane at a rate of 0.0032 mg/cm2/h and 0.002 mg/cm2/h for the emulsion and liposome gel, respectively.

Conclusion

The optimal process for the preparation of l-THP liposomes was obtained. Compared to the emulsion, the liposomes provided greater bioavailability when used transdermally. The liposomes also provided greater stability for l-THP during storage.

Effect of SEBS Molecular Structure and Formula Composition on the Performance of SEBS/PP TPE for Automotive Interior Skin

The hydrogenated styrene-butadiene-styrene block copolymer (SEBS)/Polypropylene (PP)-blended thermoplastic elastomer (TPE) is an ideal material for automotive interior skin applications due to its excellent elasticity, weather resistance, and environmentally friendly characteristics such as low odor and low volatile organic compounds (VOC). As a thin-wall injection-molded appearance skin product, it requires both high fluidity and good mechanical properties with scratch resistance. To optimize the performance of the SEBS/PP-blended TPE skin material, an orthogonal experiment and other methods were employed to investigate the impact of the formula composition and raw material characteristics, such as the styrene content and molecular structure of SEBS, on the TPE's final performance. The outcomes revealed that the ratio of SEBS/PP had the most significant influence on the mechanical properties, fluidity, and wear resistance of the final products. The mechanical performance was enhanced by increasing the PP content within a certain range. The degree of sticky touch on the TPE surface was increased as the filling oil content increased, causing the increase in sticky wear and the decrease in abrasion resistance. When the SEBS ratio of high/low styrene content was 30/70, the TPE's overall performance was excellent. The different proportions of linear/radial SEBS also had a significant effect on the final properties of the TPE. The TPE exhibited the best wear resistance and excellent mechanical properties when the ratio of linear-shaped/star-shaped SEBS was 70/30.

Orthogonal Experimental Optimization of Preparation and Microstructural Properties of a Diffusion Barrier for Tantalum-Based Silicide Coatings

To solve the problem of silicide coatings on tantalum substrates failing due to elemental diffusion under high-temperature oxidation environments and to find diffusion barrier materials with excellent effects of impeding Si elemental spreading, TaB₂ and TaC coatings were prepared on tantalum substrates by the encapsulation and infiltration methods, respectively. Through orthogonal experimental analysis of the raw material powder ratio and pack cementation temperature, the best experimental parameters for the preparation of TaB₂ coatings were selected: powder ratio (NaF:B:Al₂O₃ = 2.5:1:96.5 (wt.%)) and pack cementation temperature (1050 °C). After diffusion treatment at 1200 °C for 2 h, the thickness change rate of the Si diffusion layer prepared using this process was 30.48%, which is lower than that of non-diffusion coating (36.39%). In addition, the physical and tissue morphological changes of TaC and TaB₂ coatings after siliconizing treatment and thermal diffusion treatment were compared. The results prove that TaB₂ is a more suitable candidate material for the diffusion barrier layer of silicide coatings on tantalum substrates.

Preparation Scheme Optimization of Thermosetting Polyurethane Modified Asphalt

To solve the issue of the poor temperature stability of conventional modified asphalt, polyurethane (PU) was used as a modifier with its corresponding curing agent (CA) to prepare thermosetting PU asphalt. First, the modifying effects of the different types of PU modifiers were evaluated, and the optimal PU modifier was then selected. Second, a three-factor and three-level L9 (3³) orthogonal experiment table was designed based on the preparation technology, PU dosage, and CA dosage to prepare the thermosetting PU asphalt and asphalt mixture. Further, the effect of PU dosage, CA dosage, and preparation technology on the 3d, 5d, and 7d splitting tensile strength, freeze-thaw splitting strength, and tensile strength ratio (TSR) of the PU asphalt mixture was analyzed, and a PU-modified asphalt preparation plan was recommended. Finally, a tension test was conducted on the PU-modified asphalt and a split tensile test was performed on the PU asphalt mixture to analyze their mechanical properties. The results show that the content of PU has a significant effect on the splitting tensile strength of PU asphalt mixtures. When the content of the PU modifier is 56.64% and the content of CA is 3.58%, the performance of the PU-modified asphalt and mixture is better when prepared by the prefabricated method. The PU-modified asphalt and mixture have high strength and plastic deformation ability. The modified asphalt mixture has excellent tensile performance, low-temperature performance, and water stability, which meets the requirements of epoxy asphalt and the mixture standards.

[Toxicity attenuation processing technology and mechanism of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction]

This study explored toxicity attenuation processing technology of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction for the first time, and further explored its detoxification mechanism. Nine processed products of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction were prepared by orthogonal experiment with three factors and three levels. Based on the decrease in the content of the main hepatotoxic component diosbulbin B before and after processing of Rhizoma Dioscoreae Bulbiferae by high-performance liquid chromatography, the toxicity attenuation technology was preliminarily screened out. On this basis, the raw and representative processed products of Rhizoma Dioscoreae Bulbiferae were given to mice by gavage with 2 g·kg~(-1)(equival to clinical equivalent dose) for 21 d. The serum and liver tissues were collected after the last administration for 24 h. The serum biochemical indexes reflecting liver function and liver histopathology were combined to further screen out and verify the proces-sing technology. Then, the lipid peroxidation and antioxidant indexes of liver tissue were detected by kit method, and the expressions of NADPH quinone oxidoreductase 1(NQO1) and glutamate-cysteine ligase(GCLM) in mice liver were detected by Western blot to further explore detoxification mechanism. The results showed that the processed products of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction reduced the content of diosbulbin B and improved the liver injury induced by Rhizoma Dioscoreae Bul-biferae to varying degrees, and the processing technology of A_2B_2C_3 reduced the excessive levels of alanine transaminase(ALT) and aspartate transaminase(AST) induced by raw Rhizoma Dioscoreae Bulbiferae by 50.2% and 42.4%, respectively(P&lt;0.01, P&lt;0.01). The processed products of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction reversed the decrease protein expression levels of NQO1 and GCLM in the liver of mice induced by raw Rhizoma Dioscoreae Bulbiferae to varying degrees(P&lt;0.05 or P&lt;0.01), and it also reversed the increasing level of malondialdehyde(MDA) and the decreasing levels of glutathione(GSH), glutathione peroxidase(GPX), and glutathione S-transferase(GST) in the liver of mice(P&lt;0.05 or P&lt;0.01). In summary, this study shows that the optimal toxicity attenuation processing technology of Rhizoma Dioscoreae Bulbiferae stir-fried with Paeoniae Radix Alba decoction is A_2B_2C_3, that is, 10% of Paeoniae Radix Alba decoction is used for moistening Rhizoma Dioscoreae Bulbiferae and processed at 130 ℃ for 11 min. The detoxification mechanism involves enhancing the expression levels of NQO1 and GCLM antio-xidant proteins and related antioxidant enzymes in the liver.

The Effect of Hormone Types, Concentrations, and Treatment Times on the Rooting Traits of Morus 'Yueshenda 10' Softwood Cuttings

Enhancing the capacity of fruit trees to propagate via cuttings is an important endeavor for the high-quality development of the fruit industry. Optimizing the conditions for the cutting propagation of mulberry seedlings is an important factor that influences the industrial production of this plant; however, the currently used mulberry breeding technology system is not mature. In this experiment, an orthogonal design was used to intercept semi-woody shoots of Yueshenda 10 as cuttings and set different hormone concentrations (200, 500, 800, and 1000 mg/L), different hormone types (NAA, IBA, IAA, and ABT-1), and different soaking times (10, 30, 60, and 120 min) for cuttings. The effects of the three factors on the rooting of mulberry cuttings were investigated by soaking the cuttings in clean water for 10 min as a control. The results showed that the primary and secondary order of the three factors affecting the rooting rate of cuttings was hormone concentration > hormone type > soaking time, and the concentration of exogenous hormones had a significant impact on all rooting indicators (p < 0.05). In addition, the rooting rate (66.24%), average number of roots (7.54 roots/plant), and rooting effect index (4.23) of Yueshenda 10 cuttings reached the optimal level when soaked with 800 mg/L ABT-1 for 30 min. The longest root length (10.20 cm) and average root length (4.44 cm) of cuttings achieved the best results when soaked with 800 mg/L NAA for 60 min and 500 mg/L NAA for 30 min, respectively. On balance, it is considered that the preferred solution is to soak the cuttings of Yueshenda 10 with 800 mg/L ABT1 solution for 0.5 h.

Large-Scale and Highly Efficient Production of Ultrafine PVA Fibers by Electro-Centrifugal Spinning for NH3 Adsorption

Ultrafine Polyvinyl alcohol (PVA) fibers have an outstanding potential in various applications, especially in absorbing fields. In this manuscript, an electrostatic-field-assisted centrifugal spinning system was designed to improve the production efficiency of ultrafine PVA fibers from PVA aqueous solution for NH₃ adsorption. It was established that the fiber production efficiency using this self-designed system could be about 1000 times higher over traditional electrospinning system. The produced PVA fibers establish high morphology homogeneity. The impact of processing variables of the constructed spinning system including rotation speed, needle size, liquid feeding rate, and voltage on fiber morphology and diameter was systematically investigated by SEM studies. To acquire homogeneous ultrafine PVA fiber membranes, the orthogonal experiment was also conducted to optimize the spinning process parameters. The impact weight of different studied parameters on the spinning performance was thus provided. The experimental results showed that the morphology of micro/nano-fibers can be well controlled by adjusting the spinning process parameters. Ultrafine PVA fibers with the diameter of 2.55 μm were successfully obtained applying the parameters, including rotation speed (6500 rpm), needle size (0.51 mm), feeding rate (3000 mL h^-1), and voltage (20 kV). Furthermore, the obtained ultrafine PVA fiber mat was demonstrated to be capable of selectively adsorbing NH₃ gas relative to CO₂, thus making it promising for NH₃ storage and other environmental purification applications.

Experimental Study on Coaxial Waterjet-Assisted Laser Scanning Machining of Nickel-Based Special Alloy

The problems of the recast layer, oxide layer, and heat-affected zone (HAZ) in conventional laser machining seriously impact material properties. Coaxial waterjet-assisted laser scanning machining (CWALSM) can reduce the conduction and accumulation of heat in laser machining by the high specific heat capacity of water and can realize the machining of nickel-based special alloy with almost no thermal damage. With the developed experimental setup, the laser ablation threshold and drilling experiments of the K4002 nickel-based special alloy were carried out. The effects of various factors on the thermal damage thickness were studied with an orthogonal experiment. Experimental results have indicated that the ablation threshold of K4002 nickel-based special alloy by a single pulse is 4.15 J/cm². The orthogonal experiment results have shown that the effects of each factor on the thermal damage thickness are in the order of laser pulse frequency, waterjet speed, pulse overlap rate, laser pulse energy, and focal plane position. When the laser pulse energy is 0.21 mJ, the laser pulse frequency is 1 kHz, the pulse overlap is 55%, the focal plane position is 1 mm, and the waterjet speed is 6.98 m/s, no thermal damage machining can be achieved. In addition, a comparative experiment with laser drilling in the air was carried out under the same conditions. The results have shown that compared with laser machining in the air, the thermal damage thickness of CWALSM is smaller than 1 μm, and the hole taper is reduced by 106%. There is no accumulation and burr around the hole entrance, and the thermal damage thickness range is 0-0.996 μm. Furthermore, the thermal damage thickness range of laser machining in the air is 0.499-2.394 μm. It has also been found that the thermal damage thickness is greatest at the entrance to the hole, decreasing as the distance from the entrance increases.

Optimization of Vibration Pretreatment Microwave Curing in Composite Laminate Molding Process

Vibration pretreatment microwave curing is a high-quality and efficient composite out-of-autoclave molding process. Focusing on interlaminar shear strength, the effects of pretreatment temperature, pretreatment time and vibration acceleration on the molding performance of composite components were analyzed sequentially using the orthogonal test design method; a scanning electron microscope (SEM) and optical digital microscope (ODM) were used to analyze the void content and fiber-resin bonding state of the specimens under different curing and molding processes. The results show that the influence order of the different vibration process parameters on the molding quality of the components was: vibration acceleration > pretreatment temperature > pretreatment time. Within the parameters analyzed in this study, the optimal vibration pretreatment process parameters were: pretreatment temperature of 90 °C, pretreatment time of 30 min, and vibration acceleration of 10 g. Using these parameters, the interlaminar shear strength of the component was 82.12 MPa and the void content was 0.37%. Compared with the microwave curing process, the void content decreased by 71.8%, and the interlaminar shear strength increased by 31.6%. The microscopic morphology and mechanical properties basically reached the same level as the standard autoclave process, which achieved a high-quality out-of-autoclave curing and molding manufacturing of aerospace composite components.

Phosphoric acid pretreatment of poplar to optimize fermentable sugars production based on orthogonal experimental design

The recalcitrant structure of raw poplar limited the production of fermentable sugars when applied as the material in the pretreatment of biochemical conversions. Phosphoric acid pretreatment is an efficient method to destroy the compact lignocellulose matrix presence in the poplar. In this study, phosphoric acid pretreatment of poplar was optimised by an orthogonal experimental design [L₉(3³)] to improve enzymatic digestibility through investigating the effects of reaction temperature, time duration, and phosphoric acid concentration. The optimal conditions were selected based on the variance of chemical compositions, hemicellulose removal ratio, and delignification of the woody material after pretreatment. The optimum enzymatic hydrolysis yield of up to 73.44% was obtained when the phosphoric acid pretreatment performed at 190°C for 150 min under 1.5% of v/v phosphoric acid concentration.

Preparation and optimization of poly (lactic-co-glycolic acid) rod-shaped particles in nano size range for paclitaxel delivery

Nanoparticle shape has been acknowledged as an important design parameter due to its influence on nanoparticle interaction with biological systems. However, there is lacking of simple and scalable preparation technique for drug loaded non-spherical polymeric nanoparticles for a long time, thus hindering the potential applications. Although our previous research has modified the traditional emulsion solvent evaporation technique by adding guest molecules to prepare non-spherical poly (lactic-co-glycolic acid) (PLGA) particles, it is difficult to obtain nano-sized rods with minor axis less than 200 nm, which may have great potential in cancer therapy. Herein, in present research, the two-step ESE method was used and optimized to prepare poly (lactic-co-glycolic acid) nanorods for paclitaxel delivery. Firstly, the single-factor experiment was used to screen the influence of multi-factors including type of guest molecules, concentration of guest molecules, emulsification method, surfactant concentration, oil volume, poly (lactic-co-glycolic acid) concentration on the size and shape to determine the range of variables; based on the above range, a multi-factor and multi-level orthogonal experiment was designed. The formula is evaluated by the rod fabrication yield and the aspect ratio of major axis to minor axis. The results showed that the yield of nanorods in the optimal formula was 99% and the aspect ratio was 5.35 ± 2.05 with the minor axis of 135.49 ± 72.66 nm, and major axis of 657.77 ± 307.63 nm. In addition, the anti-cancer drug paclitaxel was successfully encapsulated in PLGA nanorods by the same technique. Our results not only enrich the ESE technique for preparing small sized poly (lactic-co-glycolic acid) nanorods, but also envision the potential application of nanorods for targeted cancer therapy with the delivery of paclitaxel.

Study on Microstructure and Properties of Black Micro-Arc Oxidation Coating on AZ31 Magnesium Alloy by Orthogonal Experiment

The effects of CuSO4 concentration, voltage and treating time on the hemisphere emissivity and corrosion resistance of AZ31B magnesium-alloy black micro-arc oxidation coatings were studied by orthogonal experiment. The microstructure, phase composition, corrosion resistance and hemisphere emissivity of the coating were investigated by scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, electrochemical test and infrared emissivity spectrometer, respectively. The results showed that the influences of each factor on corrosion current density and the hemisphere emissivity are as follows: voltage > treating time > CuSO4 concentration. The black MAO coatings are mainly composed of WO3, MgAl2O4, CuAl2O4, MgO, CuO and MgF2. The CuO and CuAl2O4 phases are the main reasons for blackness of the coatings. The coating exhibits the best corrosion resistance under the conditions of CuSO4 concentration 1.5 g/L, oxidation voltage 500 V and treating time 10 min. Additionally, the variation trends of hemispherical emissivity and roughness of the black MAO coating are the same when the composition of the coatings is similar. When the concentration of CuSO4 is 1.5 g/L, the oxidation voltage is 450 V and the treatment time is 10 min, the coating with the highest hemispherical emissivity of 0.84 can be obtained.

Electromagnetic Spectrum Allocation Method for Multi-Service Irregular Frequency-Using Devices in the Space-Air-Ground Integrated Network

The management and allocation of electromagnetic spectrum resources is the inner driving force of the construction of the space-air-ground integrated network. Existing spectrum allocation methods are difficult to adapt to the scenario where the working bandwidth of multi-service frequency-using devices is irregular and the working priorities are different. In this paper, an orthogonal genetic algorithm based on the idea of mixed niches is proposed to transform the problem of frequency allocation into the optimization problem of minimizing the electromagnetic interference between frequency-using devices in the integrated network. At the same time, a system model is constructed that takes the minimum interference effect of low-priority-to-high-priority devices as the objective function and takes the protection frequency and natural frequency as the constraint conditions. In this paper, we not only introduce the thought of niches to improve the diversity of the population but also use an orthogonal uniform crossover operator to improve the search efficiency. At the same time, we use a standard genetic algorithm and a micro genetic algorithm to optimize the model. The global searchability and local search precision of the proposed algorithm are all improved. Simulation results show that compared with the existing methods, the proposed algorithm has the advantages of fast convergence, strong stability and good optimization effect.

Prediction of Surface Roughness in Gas-Solid Two-Phase Abrasive Flow Machining Based on Multivariate Linear Equation

The main purpose of this study is to explore a surface roughness prediction model of Gas-Solid Two-Phase Abrasive Flow Machining. In order to achieve the above purpose, an orthogonal experiment was carried out. Q235 steel as processing material and white corundum with different particle sizes as abrasive particles were used in the experiment. Shape and spindle speed were the main reference factors. The range method and factor trend graph are used to comprehensively analyze the experimental results of different processing stages of the detection point, and the optimal parameter combination of A₃B₂C₁D₂ was obtained. According to the experimental results, a multiple linear regression equation was established to predict the surface roughness, and the experimental results were solved and significantly analyzed by software to obtain a highly reliable prediction model. Through experiments, modeling and verification, it is known that the maximum error between the obtained model and the actual value is 0.339 μm and the average error is 0.00844 μm, which can better predict the surface roughness of the gas-solid two-phase flow abrasive pool.

Effect of Multi-Component on Crack Resistance of High-Performance Concrete on Subway Underground Station Floor

In view of the easy cracking of the high-performance concrete (HPC) of the subway underground station floor, the effects of fly ash, basalt fiber, expansive agent, and water reducer on the compressive strength, initial crack time, through-crack time, and crack area of the HPC on a subway underground station floor at different ages by orthogonal experiment are examined. Scanning electron microscopy (SEM), X-ray diffraction (XRD), and mercury intrusion porosimetry (MIP) are used to further analyze the microstructure and product composition of the optimal ratio HPC and reference concrete. The results show that with the increase in the content of fly ash and expander, the 7 d and 28 d compressive strength of the HPC gradually decreased. However, as the content of basalt fiber increased, the 7 d and 28 d compressive strength of the HPC gradually increased. The 7 d and 28 d compressive strength of the HPC increased and then decreased with the increase in water-reducer content. When the content of fly ash, basalt fiber and expander increased, the initial crack and through-crack time of the HPC delayed gradually, and the crack area gradually decreased. When the fly-ash content reached 30%, the cracking area accounted for 65.1% of the concrete with 15% fly-ash content. When the basalt fiber content reached 0.4%, the cracking area accounted for 56.5% of the concrete with 0.1% basalt fiber content. When the expander content reached 10%, the cracking area accounted for 60.5% of the concrete with 4% expander content. With the increase in the content of water reducer, the initial crack and through-crack time of the HPC gradually advanced, and the crack area gradually increased. When the water-reducer content reached 1.3%, the cracking area accounted for 105.7% of the concrete with 1.0% water-reducer content. The addition of fly ash and expander can produce a large number of crystalline products to fill the pores, and the disordered distribution of the added basalt fibers increases the compactness of the structure; moreover, the internal micro-pores increase, and the macro-pores decrease, thus improving the crack resistance.

Microstructures and Properties of Al-Mg Alloys Manufactured by WAAM-CMT

A wire arc additive manufacturing system, based on cold metal transfer technology, was utilized to manufacture the Al-Mg alloy walls. ER5556 wire was used as the filler metal to deposit Al-Mg alloys layer by layer. Based on the orthogonal experiments, the process parameters of the welding current, welding speed and gas flow, as well as interlayer residence time, were adjusted to investigate the microstructure, phase composition and crystal orientation as well as material properties of Al-Mg alloyed additive. The results show that the grain size of Al-Mg alloyed additive becomes smaller with the decrease of welding current or increased welding speed. It is easier to obtain the additive parts with better grain uniformity with the increase of gas flow or interlayer residence time. The phase composition of Al-Mg alloyed additive consists of α-Al matrix and γ (Al12Mg17) phase. The eutectic reaction occurs during the additive manufacturing process, and the liquefying film is formed on the α-Al matrix and coated on the γ phase surface. The crystal grows preferentially along the <111> and <101> orientations. When the welding current is 90 A, the welding speed is 700 mm/min, the gas flow is 22.5 L/min and the interlayer residence time is 5 min, the Al-Mg alloy additive obtains the highest tensile strength. Under the optimal process parameters, the average grain size of Al-Mg alloyed additive is 25 μm, the transverse tensile strength reaches 382 MPa, the impact absorption energy is 26 J, and the corrosion current density is 3.485 × 10−6 A·cm−2. Both tensile and impact fracture modes of Al-Mg alloyed additive are ductile fractures. From the current view, the Al-Mg alloys manufactured by WAAM-CMT have a better performance than those produced by the traditional casting process.

Optimization of AlCrSiWN Coating Process Parameters and Performance Study by the Matrix Analysis Method

An AlCrSiWN coating was prepared on a cemented carbide substrate by the arc ion plating technology. The optimization of the coating process was carried out by matrix analysis of orthogonal experiments to calculate the influence of the process parameters on the hardness, bonding and roughness indexes of the coating, determine the optimal coating process parameters, and focus on the influence of the bias voltage on the microscopic morphology, mechanical properties and friction properties of the coating. The results showed that the influence of the process parameters on the indexes of the orthogonal experiments was in the following order: bias voltage > arc current > N2 flow rate. The optimal solution was achieved with an arc current of 160 A, a bias voltage of −80 V, and a N2 flow rate of 600 sccm. Properly increasing the bias voltage improved the microscopic morphology, mechanical properties and wear resistance of the coating. When the bias voltage was −80 V, the coating surface presented fewer large particles with a less uniform size and no obvious crater defects; in addition, the cross-sectional structure changed from grape-like to columnar, and the coating had higher hardness, lower roughness and better bond strength. In the friction performance test, coating at a −80 V bias voltage showed better wear resistance, which was reflected in lower friction coefficient and wear, and the wear mechanism mainly consisted of adhesion and oxidation wear.

Optimization Design of the Landscape Elements in the Lhasa Residential Area Driven by an Orthogonal Experiment and a Numerical Simulation

Landscape elements have become an important means to improve the quality of life of residents because of their direct influence on the thermal environment, but the selection and configuration of landscape elements have different effects on human thermal comfort in different climate conditions. In this research, the typical residential area of Lhasa in Tibet was taken as the research object, the experimental scheme was prepared using an orthogonal test, and the simulation was carried out using ENVI-met to explore the influences of the green configuration, water area, and ground reflectance, as well as their interaction with the thermal environment in winter and summer under alpine climate conditions. Taking the physiological equivalent temperature (PET) as the optimization index, the optimal design scheme for the synergistic effect of the residential landscape elements was determined. The results were as follows. (1) The order of the landscape configuration factors was as follows: green configuration > water area > leaf area index > ground reflectance in summer. In winter, the order was green configuration > water area > ground reflectance > leaf area index (LAI). (2) With the combined driving of the orthogonal test and the numerical simulation, the optimal scheme of the landscape elements was determined, which was “tree shrub lawn, water area ratio 16%, ground reflectance 0.5, and LAI = 3 m2/m3”. (3) Finally, the optimal design strategy of the landscape configuration was proposed for the typical outdoor active space of the Lhasa residential area.

Experiment on the Properties of Soda Residue-Activated Ground Granulated Blast Furnace Slag Mortars with Different Activators

Soda residue (SR), a solid waste generated in the production of Na₂CO₃ during the ammonia soda process, with a high pH value of 12, can be used as an activator of alkali-activated ground granulated blast furnace slag (GGBFS) cementitious materials. Three groups of experiments on SR-activated GGBFS mortars were designed in this paper to assess the role of the dominant parameters on fluidity and compressive strength of mortars. The results indicate that for fluidity and mechanical properties, the optimal scheme of SR-activated GGBFS mortars is 16:84–24:76 S/G, 0.01 NaOH/b, 0.05 CaO/b, and 0.50 w/b, with fluidity and compressive strength (28 d) of the mortars being 181–195 mm and 32.3–35.4 MPa, respectively. Between 2.5–10% CaCl₂ addition to CaO (5%)-SR (24%)-activated GGBFS mortar is beneficial to the improvement of the compressive strength of C2, whereas the addition of CaSO₄ is harmful. The main hydration products of mortars are ettringite, Friedel’s slat, and CSH gels. The results provide a theoretical basis and data support for the utilization of SR.

Study on the Material Properties of Microconcrete by Dynamic Model Test

As an important water conveying structure, the seismic safety of the hydraulic aqueduct has attracted considerable interest. Different from the general bridge structure, the seismic analysis of the aqueduct structure needs to consider its fluid–structure interaction. The existing numerical simulation methods cannot truly reflect the fluid–solid coupling mechanism. Therefore, scholars began to use shaking table tests to study the fluid–structure interaction mechanism. However, the research is immature, and it is mostly focused on the seismic response analysis, and there are few studies on the model test similarity ratio and model material properties. Based on this, in this paper, according to the requirements of the test similarity ratio, the orthogonal experiment was used to explore the influence of barite sand content, water–cement ratio, fine sand ratio, and lime ratio on the mechanical properties of microconcrete. The performance indicators of microconcrete under different mix ratios vary widely, with a minimum variation of 19% and a maximum of 102%. Barite sand has the most significant control effect on the density, and the water–cement ratio has the most significant control effect on the compressive strength and elastic modulus. The density variation range is 2.37–2.81 g/cm³, the cube compressive strength variation range is 18.37–36.94 MPa, and the elastic modulus variation range is 2.11 × 10⁴–3.28 × 10⁴ MPa. This study will provide certain evidence for the similarity ratio design and material selection of the scaled model test of the fluid–solid coupling structure.

Establishment of a New Cryopreservation Solution for Chimeric Antigen Receptor T Cells

Preservation and transportation are essential for the clinical application of chimeric antigen receptor T (CAR-T) cells. This study aimed to optimize a cryopreservation solution for CAR-T cells and evaluate the antitumor efficiency of CAR-T cells using this optimized solution in vitro and in vivo. First, the stability of the cryopreservation solution for CAR-T infusion was detected by the L27 (3⁷) orthogonal experiment. Subsequently, osmolality and pH were analyzed for the preservation reagent. Additionally, apoptosis and CAR expression of CAR-T cells were measured by flow cytometry, and the cytotoxicity was determined by calcein-AM staining. The results showed that cryopreservation solutions used in this study demonstrated high chemical stability, which induced only 2% CAR-T cells apoptosis in optimal solutions, which were slightly lower than other commercial solutions. Moreover, the CAR expression was not significantly affected by preservation with these solutions. There were no significant differences in the cytotoxicity between fresh and thawed CAR-T cells cryopreserved in the cryopreservation solutions in vivo and in vitro. This study developed a new cryopreservation solution for CAR-T cells, and it was safe and also had negligible effects on the CAR-T cells antitumor activity.

Optimisation of Lapping Process Parameters for Single-Crystal 4H-SiC Using Orthogonal Experiments and Grey Relational Analysis

Lapping is one of the standard essential methods to realise the global planarization of SiC and other semiconductor substrates. It is necessary to deeply study the mechanism to obtain SiC lapping process parameters with a strong comprehensive lapping performance (i.e., high material removal rate (MRRm), small surface roughness (Ra), and low total thickness variation (TTV)). The effects of the lapping process parameters and their interactions on lapping performance for SiC were investigated using orthogonal experiments; the effects on the MRRm, Ra, TTV, and optimal parameters under the conditions of a single evaluation index were investigated using intuitive analysis (range analysis, variance analysis, and effect curve analysis). The entropy value method and grey relational analysis were used to transform the multi-evaluation-index optimisation into a single-index optimisation about the grey relational grade (GRG) and to comprehensively evaluate the lapping performance of each process parameter. The results showed that the lapping plate types, abrasive size, and their interaction effect had the most significant effects on MRRm and Ra, with a contribution of over 85%. The interaction between the lapping plate types and abrasive size was also found to have the most significant effect on TTV, with a contribution of up to 51.07%. As the lapping plate's hardness and abrasive size increased, the MRRm and Ra also gradually increased. As the lapping normal-pressure increased, MRRm increased, Ra gradually decreased, and TTV first decreased and then increased. MRRm, Ra, and TTV first increased and then decreased with increasing abrasive concentration. Compared to the optimisation results obtained by intuitive analysis, the process parameter optimised by the grey relational analysis resulted in a smooth surface with an MRRm of 90.2 μm/h, an Ra of 0.769 nm, and a TTV of 3 μm, with a significant improvement in the comprehensive lapping performance. This study reveals that a combination of orthogonal experiments and grey relational analysis can provide new ideas for optimising the process parameters of SiC.

Research on variation law of geophysical drill-bit downhole flow field under the interaction of multiple hydraulic factors

Mountain geophysical prospecting operations play an important role in the entire petroleum exploration field. Geophysical drill-bit is the main tool for mountain geophysical prospecting operations. Its hydraulic structure directly affects the downhole flow field and then affects the chip removal efficiency and drilling efficiency of the bit. At present, most of the scholars' research is focused on Poly Diamond Crystalline bit, roller bit, etc., and the research on geophysical drill-bit is less, and most of them study the downhole flow field based on the change of single hydraulic structure. The primary objective of this research is to study the variation law of the downhole flow field under the interaction of multiple hydraulic structure factors. The drilling time and cuttings size of two geophysical drill-bits with different hydraulic structures are compared, and the key hydraulic structure factors are selected for analysis. Using numerical simulation software, take different levels of key hydraulic structure parameters and carry out orthogonal experiments. Under the interaction of various factors, study the flow field distribution in the flow channel, the downhole, and the annulus area of the shaft lining. The hydraulic structure of the geophysical drill-bit is closely related to the drilling speed and chip removal efficiency. When multiple hydraulic factors are changed, the diameter of the flow channel is the best when it is 10-12.5 mm, the inclination of the flow channel should be set as close as possible to the center of the downhole, and the length of the chip groove increases, the movement of cuttings is more stable. Variation law of downhole flow field under the interaction of multiple hydraulic factors is studied. This study provides a basis for the hydraulic structure design and optimization of the geophysical drill-bit.

Preparation, amino acid composition, and in Vitro antioxidant activity of okra seed meal protein hydrolysates

To improve the utilization of okra seed, acidic and enzymatic hydrolyses of producing protein hydrolysates were respectively optimized by orthogonal experiment and response surface methodology using the degree of hydrolysis (DH) as evaluating index. Amino acid composition and antioxidant capacity in vitro of two kinds of hydrolysates were both analyzed. The degree of acidic hydrolysis was 58.53 ± 1.92% under the following optimized condition: hydrolyzing time 40 hr, temperature 95°C, ratio of acid solution to okra seed meal (OSM) powder was 5:1 (V:W/ml:g), and hydrochloric acid concentration was 18% (W/W). The degree of enzymatic hydrolysis was 16.26 ± 0.56% under the optimized condition: hydrolyzing time 8.20 hr, ratio of buffer to OSM powder was 10:1, and enzyme dosage was 3,100 International Units (IU) g-1. Enzymatic hydrolysates had a fuller range of amino acids and antioxidant capacity than acidic hydrolysates. The results provide technical support for the expansion of okra seed utilization.

[Nonlinear Response Characteristics and Control Scheme for Ozone and Its Precursors Based on Orthogonal Experimental Methods]

There is a highly nonlinear relationship between ozone concentrations and its precursor emissions in different regions and at different times, which makes developing effective prevention and control measures difficult. An orthogonal experimental method was introduced to assess the influence of ozone precursors and their interactions on ozone formation, clarify the sensitivity of ozone generation, and propose an optimal control scheme. Based on the WRF-Chem air quality model and an emission inventory of air pollutants in Wuhai City in 2018, this study used an ozone pollution event in the Haibowan urban area (August 17 to 20 2018) to investigate the nonlinear response of ozone formation to its precursors. The orthogonal experiment shows that NO_x, VOCs interactions with CO, CO, and interactions between pollutants and meteorological factors are the main factors affects ozone concentrations in the Haibowan urban area. Ozone generation was most sensitive to NO_x concentrations during the hours 12:00-18:00 when standard values were exceeded. The ozone concentrations decreased significantly by 12.6 μg·m^-3 (7.8%) as NO_x, VOCs, and CO were reduced by 60%, 30%, and 30%, respectively. Through the analysis of chemical reaction mechanisms, it is concluded that VOCs and CO affect the photochemical reaction by reacting with·OH, HO₂·and other free radicals, which causes the significant interaction between VOCs and CO in the generation of ozone. This method provides a new approach for researching the nonlinear response of ozone formation to its precursors and for proposing ozone pollution control schemes.

Green waste compost as a substitute for turfy soil in external-soil spray seeding substrate

The scarcity of turfy soil (TS), which is the most commonly used external-soil spray seeding (ESSS) substrate component, has recently increased. The aim of this study was to introduce a substitute for TS as an organic matter additive in substrate. Green waste compost (GWC) that was combined with sandy loam soil, polyacrylamide (PAM), and super absorbent polymer (SAP) was used for preparing the soil substrate. Further, a modified soil-spraying experiment and artificial rainfall experiments with an orthogonal design (L₁₆4³) were conducted. These experiments assessed the feasibility of GWC as a component of ESSS substrate and the optimal formulation. The results indicated that the degree of influence of the three factors controlling the amended substrate is GWC > PAM > SAP. GWC improved the physical and chemical properties of the substrate, as well as the seed germination rate and seedling growth. Significant improvements can be observed with respect to the soil bulk density, soil porosity, steady infiltration rate, and anti-shearing strength (p < .01). Additionally, the runoff and soil loss decreased under heavy rainfall. Except for the soil nutrients and seedling height, all other indicators of the GWC substrates were better than those of the commercially available TS substrates. Principal component analysis and range analysis revealed that the optimum values of various design parameters were 40% for the compost volume content, 200 g m^-3 for PAM and 100 g m^-3 for SAP. Based on these results, GWC can be considered to be an effective alternative to TS for ESSS.

[Multi-index optimization of extraction process of Fengyin Decoction based on BAS-GA-BP neural network combined with entropy weight method]

To optimize the ethanol extraction technology parameters of Fengyin Decoction by orthogonal experiment combined with beetle antennae search(BAS)-genetic algorithm(GA)-back propagation neural network(BPNN). Based on single factor investigation, the extraction temperature, ethanol volume, extraction time, and ethanol concentration were used as orthogonal experiment factors, and entropy weight method was used to calculate the comprehensive scores of aloe-emodin, glycyrrhizic acid ammonium salt, rhein, emodin, chrysophanol, physcion, cinnamaldehyde, 6-gingerol, extraction ratio and fingerprint similarity. BAS-BPNN model was established, and then, GA was used to predict the optimal extraction process. The results showed that BAS-BPNN was optimized to obtain the optimal ethanol extraction process of Fengyin Decoction as follows: extraction temperature of 87 ℃, adding 9 times of 75 % ethanol, and extracting for 47 minutes, with a comprehensive score of 1.052 9. Meanwhile, the optimal process parameters obtained by orthogonal design were as follows: the extraction temperature of 80 ℃, adding 10 times of 75% ethanol, extracting for 30 minutes, with a comprehensive score of 1.003 7. The comprehensive score of the process obtained from the BAS-BPNN model was slightly better than that from the orthogonal test, indicating that the optimized process from BAS-BPNN model was more ideal, so it was finally determined as the best extraction process for Fengyin Decoction. The process of Fengyin Decoction obtained from BAS-GA-BPNN has high extraction efficiency and good stability, which provides reference for the subsequent development and quality control.

Dust accumulated fungi in air-conditioning system: Findings based on field and laboratory experiments

This study analyzes the growth and reproduction of dust accumulated fungi (DAF) in an air-conditioning system based on field measurement and molecular biology, laboratory experiment and prediction modelling. The field measurement was conducted to collect dust in filter screen, surface cooler and air supply duct of two air handling units (AHUs). The results indicate that dust volume and fungal number in two AHUs generally met the hygienic specification of public buildings, but the cleansing did not fulfil requirements. High-throughput sequencing was conducted, revealing that the dominant fungal species were Alternaria_betae-kenyensis, Cladosporium_delicatulum, Aspergillus_sydowii, Verticillium_dahliae. Laboratory experiment was conducted to analyze the impact of several factors (e.g. growth time, temperature, relative humidity, duct material) and their combination on the DAF growth. The results indicate that fungal growth increased with time, peaking at 4 days or 5 days. Higher relative humidity or temperature was conducive to fungal growth. The orthogonal experiment revealed that the condition of "antibacterial composite, 22 ± 1 °C and 45%-55% RH" had the strongest inhibiting impact on fungal growth. Logistic model, Gompertz model and square-root model were further developed to predict the fungal growth under different conditions. The results show that the Logistic model had high feasibility and accuracy, the Gompertz model was feasible with lower accuracy and the square-root model was feasible with high accuracy. Overall, this study facilitates the understanding of the DAF growth in air-conditioning ducts, which is important for real-time prediction and timely control of the fungal contamination.

Simulation Analysis of the Influence of Nozzle Structure Parameters on Material Controllability

With the evolution of three-dimensional (3D) printing, many restrictive factors of 3D printing have been explored to upgrade the feasibility of 3D printing technology, such as nozzle structure, print resolution, cell viability, etc., which has attracted extensive attention due to its possibility of curing disease in tissue engineering and organ regeneration. In this paper, we have developed a novel nozzle for 3D printing, numerical simulation, and finite element analysis have been used to optimize the nozzle structure and further clarified the influence of nozzle structure parameters on material controllability. Using novel nozzle structure, we firstly adopt ANSYS-FLUENT to analyze material controllability under the different inner cavity diameter, outer cavity diameter and lead length. Secondly, the orthogonal experiments with the novel nozzle are carried out in order to verify the influence law of inner cavity diameter, outer cavity diameter, and lead length under all sorts of conditions. The experiment results show that the material P diameter can be controlled by changing the parameters. The influence degree of parameters on material P diameter is shown that lead length > inner cavity diameter > outer cavity diameter. Finally, the optimized parameters of nozzle structure have been adjusted to estimate the material P diameter in 3D printing.

Preparation of Hydrophobic Surface on PLA and ABS by Fused Deposition Modeling

In the fields of agriculture, medical treatment, food, and packaging, polymers are required to have the characteristics of self-cleaning, anti-icing, and anti-corrosion. The traditional preparation method of hydrophobic coatings is costly and the process is complex, which has special requirements on the surface of the part. In this study, fused deposition modeling (FDM) 3D printing technology with design and processing flexibility was applied to the preparation of hydrophobic coatings on polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) parts, and the relationship between the printing process parameters and the surface roughness and wettability of the printed test parts was discussed. The experimental results show that the layer thickness and filling method have a significant effect on the surface roughness of the 3D-printed parts, while the printing speed has no effect on the surface roughness. The orthogonal experiment analysis method was used to perform the wettability experiment analysis, and the optimal preparation process parameters were found to be a layer thickness of 0.25 mm, the Grid filling method, and a printing speed of 150 mm/s.

Orthogonal Experimental Research on Dielectrophoresis Polishing (DEPP) of Silicon Wafer

Silicon wafer with high surface quality is widely used as substrate materials in the fields of micromachines and microelectronics, so a high-efficiency and high-quality polishing method is urgently needed to meet its large demand. In this paper, a dielectrophoresis polishing (DEPP) method was proposed, which applied a non-uniform electric field to the polishing area to slow down the throw-out effect of centrifugal force, thereby achieving high-efficiency and high-quality polishing of silicon wafers. The principle of DEPP was described. Orthogonal experiments on important polishing process parameters were carried out. Contrast polishing experiments of silicon wafer were conducted. The orthogonal experimental results showed that the influence ratio of electric field intensity and rotation speed on material removal rate (MRR) and surface roughness was more than 80%. The optimal combination of process parameters was electric field intensity 450 V/mm, rotation speed 90 rpm, abrasive concentration 30 wt%, size of abrasive particle 80 nm. Contrast polishing experiments indicated that the MRR and material removal uniformity of DEPP were significantly better than traditional chemical mechanical polishing (CMP). Compared with the traditional CMP, the MRR of DEPP was increased by 17.6%, and the final surface roughness of silicon wafer reached Ra 0.31 nm. DEPP can achieve high-efficiency and high-quality processing of silicon wafer.

[Quantitative determination and optimun extraction technique of nine compounds of Paeoniae Radix Alba]

OBJECTIVE

To establish the optimum extraction technique and high performance liquid chromatographic (HPLC) method to simultaneously quantify nine compounds of gallic acid, hydroxy-paeoniflorin, catechin, albiflorin, paeoniflorin, pentagalloylglucose, benzoic acid, benzoylpaeoniflorin and paeonol in Paeoniae Radix Alba.

METHODS

Linear gradient elution was applied using water containing 0.1%phosphoric acid and acetonitrile as the mobile phase with a flow rate of 0.8 mL/min, column temperature of 30℃ and wavelength of 230 nm. The method of ultrasound extraction was used. Methanol and ethanol were used as extraction solvents, and three factors and three levels of orthogonal experiments was designed using L 9(3 4) table to investigate the effects of solvent concentration, ratio of liquid to material and extraction time on the total content of nine components of Paeoniae Radix Alba.

RESULTS

HPLC method was verified to have high specificity, sensitivity and accuracy through methodological validation, and it could be used for simultaneous quantitative analysis of nine components of Paeoniae Radix Alba. The results showed that the optimum extraction technology of nine components of Paeoniae Radix Alba was using 70%ethanol as extraction solvent, ratio of liquid to material was 200 mL/g and ultrasound extraction time was 30 min.

CONCLUSIONS

HPLC method for the simultaneous determination of nine components of Paeoniae Radix Alba is established, and the optimum extraction technology is confirmed.

Almond Shell-Derived, Biochar-Supported, Nano-Zero-Valent Iron Composite for Aqueous Hexavalent Chromium Removal: Performance and Mechanisms

Nano-zero-valent iron biochar derived from almond shell (nZVI-ASBC) was used for hexavalent chromium (CR) removal. Experiments showed that pH was the main factor (p < 0.01) that affected the experimental results. At a dosage of 10 mg·L⁻¹ and pH of 2–6, in the first 60 min, nZVI-ASBC exhibited a removal efficiency of 99.8%, which was approximately 20% higher than the removal yield at pH 7–11. Fourier transform infrared spectroscopy results indicated N-H was the main functional group that influenced the chemisorption process. The pseudo second-order dynamics and Langmuir isotherm models proved to be the most suitable. Thermodynamic studies showed that the reaction was exothermic and spontaneous at low temperatures (T < 317 K). Various interaction mechanisms, including adsorption and reduction, were adopted for the removal of Cr(VI) using the nZVI-ASBC composite. The findings showed that the BC-modified nZVI prepared with almond shell exerts a good effect and could be used for the removal of Cr(VI).

Optimization design and experimental study of vortex pump based on orthogonal test

To study the effects of the performance of different types of impeller on the vortex pump, orthogonal test design, which is carried out by combining experimental test and numerical calculation, is adopted to optimize the type of design structure for the impeller in vortex pump. To find out the folding blade angle, the position of the folding point in the whole blade, and whether to wedge folding blade, an orthogonal test scheme with three factors and two levels is designed. A numerical simulation test is conducted for each scheme by analyzing the performance curve of orthogonal test plan to find the optimal performance of the program and analyzing the test data of each scheme to obtain the primary and secondary orders of the impact performance in the angle of folding blades of the vortex pump, the position of folding point of blades, and the wedge shape of blades. The results show that the optical blade type combination is the blade angle R30F60, the folding point is at 2/3 of the whole blade, and the blade does not adopt radial wedge. The optimal combination scheme is 36% higher than the design value at the rated flow head, the efficiency is 18.75% higher than the design value, the high-efficiency zone of the vortex pump is wider, and the performance meets the design requirements. Through orthogonal experimental design, the design cycle of vortex pump can be shortened effectively, the design level of vortex pump can be improved, and the hydraulic model with superior performance can be obtained.

Sensitivity analysis of heat dissipation factors in a hot oil pipeline based on orthogonal experiments

The study of phase-change heat-transfer characteristics of crude oil has been one of the hot issues in the field of gathering and transportation. The process of phase-change heat transfer of crude oil involves many complicated problems such as natural convection treatment, latent heat treatment, phase-change interface determination and fluid characteristic change. A mathematical model based on the additional capacity heat method is proposed in this article, and the momentum equations of crude oil liquid phase are presented for Newtonian and non-Newtonian fluids. The aim of this study was to investigate the influence of different factors on the heat transfer performance during the shutdown process of an overhead pipe. Experiments were conducted to verify the model and the solution method; the experimental and model results showed good agreement with a maximum relative error of 4.57%. The temperature fields and solidification conditions of crude oil in pipelines under different shutdown conditions were determined, and the sensitivity of the main effect factors was determined through an orthogonal experiment. The results show that the order of influence was oil initial temperature >thickness of insulating layer >air temperature >thickness of wax layer. The results of the study have important guiding significance on the control of shutdown time and the determination of restarting schemes.

Optimization of the fermentation parameters for the production of Ganoderma lucidum immunomodulatory protein by Pichia pastoris

In order to obtain a better fermentation parameter for the production of recombinant Ganoderma lucidum immunomodulatory protein (rFIP-glu), an engineered Pichia pastoris GS115 was investigated on the fermentation time, temperature, methanol concentration and initial pH of media, while immunomodulatory activities of the rFIP-glu was confirmed. L₉(3³) orthogonal experiment were firstly employed to optimize various fermentation parameters in the shake-flask level. The optimized fermentation parameters were subsequently verified in a 5 L fermenter. Biological activities including cell viability and tumor necrosis factor-alpha (TNF-α) mRNA of the rFIP-glu were evaluated on murine macrophage RAW264.7 cells. The results showed that the yield of rFIP-glu was up to 368.71 μg/ml in the shake-flask, and 613.47 μg/ml in the 5 L fermenter, when the Pichia pastoris was incubated in basic media with the methanol concentration 1.0% and initial pH 6.5, and with constant shaking at 280 rpm for 4 days at 26 °C. In vitro assays of biological activity indicated that rFIP-glu had significant toxicity against RAW264.7 cells, and possessed the ability to induce TNF-α mRNA expression in macrophage RAW264.7 cells. In conclusion, engineered P. pastoris showed a good fermentation property under the optimum fermentation parameters. It could be a candidate industrial strain for further study.

Ceramsite production from sediment in Beian River: characterization and parameter optimization

In order to realize pollution control and resource recovery, sediment from Beian River in Mudanjiang City China was used for ceramsite production. The maximum content of total nitrogen (TN), total phosphorus (TP) and organic matter (OM) in sediments of Beian River were 2975 mg kg^-1, 2947 mg kg^-1 and 29.6%, respectively. So, it should be treated properly for resource utilization. The orthogonal experiment of L ₁₆ (4⁵) was adopted to determine the best conditions for ceramsite production and the result demonstrated that the sewage sludge ratio of 15%, binder ratio of 5%, pre-heating temperature of 450°C, sintering temperature of 1150°C and firing time of 23 min were the optimum conditions. The corresponding product met with the standard of CJ/T 299-2008 and the heavy metal leaching experiment showed it was lower than the threshold of China's industrial standard. Thus, it demonstrated that ceramsite production was a feasible way for utilization of sediment.

Investigation of Plasma Activated Si-Si Bonded Interface by Infrared Image Based on Combination of Spatial Domain and Morphology

This paper presents a detection method for characterizing the bonded interface of O2 plasma activated silicon wafer direct bonding. The images, obtained by infrared imaging system, were analyzed by the software based on spatial domain and morphology methods. The spatial domain processing methods, including median filtering and Laplace operator, were applied to achieve de-noising and contrast enhancement. With optimized parameters of sharpening operator patterns, disk size, binarization threshold, morphological parameter A and B, the void contours were clear and convenient for segmentation, and the bonding rate was accurately calculated. Furthermore, the void characteristics with different sizes and distributions were also analyzed, and the detailed statistics of the void's number and size are given. Moreover, the orthogonal experiment was designed and analyzed, indicating that O2 flow has the greatest influence on the bonding rate in comparison with activated time and power. With the optimized process parameters of activated power of 150 W, O2 flow of 100 sccm and time of 120 s, the testing results show that the bonding rate can reach 94.51% and the bonding strength is 12.32 MPa.

A Convenient, Rapid, Sensitive, and Reliable Spectrophotometric Assay for Adenylate Kinase Activity

Enzymatic activity assays are essential and critical for the study of enzyme kinetics. Adenylate kinase (Adk) plays a fundamental role in cellular energy and nucleotide homeostasis. To date, assays based on different principles have been used for the determination of Adk activity. Here, we show a spectrophotometric analysis technique to determine Adk activity with bromothymol blue as a pH indicator. We analyzed the effects of substrates and the pH indicator on the assay using orthogonal design and then established the most optimal assay for Adk activity. Subsequently, we evaluated the thermostability of Adk and the inhibitory effect of KCl on Adk activity with this assay. Our results show that this assay is simple, rapid, and precise. It shows great potential as an alternative to the conventional Adk activity assay. Our results also suggest that orthogonal design is an effective approach, which is very suitable for the optimization of complex enzyme reaction conditions.

Influence of Layer Thickness, Raster Angle, Deformation Temperature and Recovery Temperature on the Shape-Memory Effect of 3D-Printed Polylactic Acid Samples

The success of the 3D-printing process depends upon the proper selection of process parameters. However, the majority of current related studies focus on the influence of process parameters on the mechanical properties of the parts. The influence of process parameters on the shape-memory effect has been little studied. This study used the orthogonal experimental design method to evaluate the influence of the layer thickness H, raster angle θ, deformation temperature Td and recovery temperature Tr on the shape-recovery ratio Rr and maximum shape-recovery rate Vm of 3D-printed polylactic acid (PLA). The order and contribution of every experimental factor on the target index were determined by range analysis and ANOVA, respectively. The experimental results indicated that the recovery temperature exerted the greatest effect with a variance ratio of 416.10, whereas the layer thickness exerted the smallest effect on the shape-recovery ratio with a variance ratio of 4.902. The recovery temperature exerted the most significant effect on the maximum shape-recovery rate with the highest variance ratio of 1049.50, whereas the raster angle exerted the minimum effect with a variance ratio of 27.163. The results showed that the shape-memory effect of 3D-printed PLA parts depended strongly on recovery temperature, and depended more weakly on the deformation temperature and 3D-printing parameters.

Optimization of processing technology of Rhizoma Pinelliae Praeparatum and its anti-tumor effect

BACKGROUND

Rhizoma Pinelliae is the dried tuber of Pinellia ternata (Thunb.) Breit. Modern pharmacological studies have shown that Rhizoma Pinelliae has antitussive, antiemetic, glandular secretion inhibiting and antitumor effects.

OBJECTIVES

To optimize the processing technology of Rhizoma Pinelliae Praeparatum, and to study its anti-tumor effect.

METHODS

Orthogonal design method was applied to analyze the effects of factors such as licorice concentration volume, soaking time and processing temperature on processing technology of Rhizoma Pinelliae Praeparatum; MTT assay and flow cytometry were used to determine the inhibitory effect of Rhizoma Pinelliae Praeparatum on Bel-7402 cells.

RESULTS

During the processing of Rhizoma Pinelliae Praeparatum, the size of influence of licorice concentration volume, soaking time and processing temperature on processing results of Rhizoma Pinelliae was: B>C>A in descending order, i.e. soaking time>processing temperature>licorice concentration volume, different concentrations of Rhizoma Pinelliae Praeparatum ethanol extracts could all exert inhibitory effect on the growth and proliferation of Bel-7402 cells, and with the increase of drug concentration and the extension of culture time, the cell proliferation inhibitory effect of Rhizoma Pinelliae Praeparatum ethanol extract became more and more evident. Apoptotic rate of 1.5 mg/ml Rhizoma Pinelliae Praeparatum ethanol extract group reached 13.53%, the difference was extremely significant compared with the control group. In conclusion the factor most influential to the processing technology of Rhizoma Pinelliae Praeparatum was soaking time, followed by processing temperature, the factor least influential was licorice concentration volume.

CONCLUSION

Rhizoma Pinelliae Praeparatum has inhibitory effect on growth and proliferation of Bel-7402 cells.

An optimal polymerization process for low mean molecular weight HBOC with lower dimer

The new research tried to improve the distribution of molecular weight of Hb-based oxygen carriers (HBOC), a bottleneck of glutaraldehyde (GDA)-polymerization process. The orthogonal experiments were done on the basis of the early study of human placenta Hemoglobin (Hb)-crosslinked-GDA and three factors were selected including the molar ratio of GDA and Hb, Hb concentration, and the rate of the feeding GDA. The optimal match condition of polymerization process prepared for the purpose of lower mean molecular weight, content of super-weight molecule, and the content of dimer. The results showed that the molar ratio of GDA and Hb was the greatest influencing factor on the molecular weight distribution of polymerized-Hb, followed by the Hb concentration, and the last is the rate of feeding GDA. The optimum matching conditions had reached the objective that the mean molecular weight with 155.54 ± 5.79, the content of dimer with 17.23 ± 3.71, and content of super-weight molecule with 0.17 ± 0.09, and the results can be repeated in the 30 times expansion experiments.

Treatment of oilfield fracturing wastewater by a sequential combination of flocculation, Fenton oxidation and SBR process

In this study, a combined process was developed that included flocculation, Fenton oxidation and sequencing batch reactor (SBR) to treat oilfield fracturing wastewater (FW). Flocculation and Fenton oxidation were applied to reduce chemical oxygen demand (COD) organic load and to enhance biodegradability, respectively. For flocculation, the optimum conditions were: polymeric aluminium chloride dosage, 40 mg/L; polyacrylamide dosage, 4 mg/L; dilution ratio, 1:2 and stirring time, 30 min. For Fenton oxidation, a total reaction time of 60 min, a H₂O₂dosage of 2 m mol/L, with a [H₂O₂]/[FeSO₄] ratio of 2 were selected to achieve optimum oxidation. Under these optimum flocculation and Fenton oxidation conditions, the COD removal efficiency was found to be 76.6%. Following pretreatment with flocculation and Fenton oxidation, the FW was further remediated using a SBR. Results show that COD was reduced to 92 mg/L, and the overall water quality of the final effluent could meet the class I national wastewater discharge standard of petrochemical industry of China.

Nitric oxide removal by wastewater bacteria in a biotrickling filter

Nitric oxide (NO) is one of the most important air pollutants in atmosphere mainly emitted from combustion source. A biotrickling filter was designed and operated to remove NO from an air stream using bacteria extracted from the sewage sludge of a municipal sewage treatment plant. To obtain the best operation conditions for the biotrickling filter, orthogonal experiments (L9(3(4))) were designed. Inlet oxygen concentration was found to be the most significant factor of the biotrickling filter and has a significant negative effect on the system. The optimal conditions of the biotrickling filter occurred at a temperature of 40°C, a pH of 8.0 and a chemical oxygen demand of 165 mg/L in the recycled water with no oxygen in the system. The bacteria sample was detected by DNA sequencing technology and showed 93%-98% similarity to Pseudomonas mendocina. Moreover, a full gene sequencing results indicated the bacterium was a brand new strain and named as P. mendocina DLHK. This strain can transfer nitrate to organic nitrogen. The result suggested the assimilation nitrogen process in this system. Through the isotope experimental analysis, two intermediate products ((15)NO and (15)N2O) were found. The results indicated the denitrification function and capability of the biotrickling filter in removing NO.

Removement of thiocyanate from industrial wastewater by microwave-Fenton oxidation method

The microwave radiation oxidation process, Fenton as catalytic agent, was used to remove the thiocyanate from the industrial wastewater. The effects of microwave power, radiation time, pH and the feeding in ways of catalyst on the degradation rate of synthetic wastewater were investigated using the microwave radiation oxidation process by orthogonal experiment. The results show Fenton catalyst ratio was 1:20, the microwave radiation power was 900 W, the microwave radiation time was 7 min and the value of pH was 3. Under the optimum conditions, the removal of KSCN can reach over 90%. The apparent kinetics of removal was studied, which conformed to kinetics first-class reaction. In short, for the thiocyanate from the industrial wastewater, microwave-Fenton oxidation method is feasible and effective.

A study on the extraction and purification process of lily polysaccharide and its anti-tumor effect

The objective of this paper was to extract and purify lily polysaccharide and to study its anti-H22 hepatoma effect in mice. Orthogonal experimental method was used to analyze the factors influencing the extraction and purification of lily polysaccharide, and the anti-tumor effect of lily polysaccharide was studied by acting it on H22-bearing mice. The results showed that the size of influence of various factors on the extraction results of lily polysaccharide were extraction time, extraction times and extraction temperature in decreasing order. Lily polysaccharide can enhance the immune function of H22 tumor-bearing mice, and inhibit the growth of H22 tumor. The study concluded that the optimal conditions for the extraction and purification of lily polysaccharide should be extraction times of 3 times, an extraction time of 4 h each, and an extraction temperature of 60°C; lily polysaccharide has an anti-tumor effect.