Modulating the d-Band Center of RuO2 via Ni Incorporation for Efficient and Durable Li-O2 batteries

Rechargeable Li-O2 batteries (LOBs) are considered as one of the most promising candidates for new-generation energy storage devices. One of major impediments is the poor cycle stability derived from the sluggish reaction kinetics of unreliable cathode catalysts, hindering the commercial application of LOBs. Therefore, the rational design of efficient and durable catalysts is critical for LOBs. Optimizing surface electron structure via the negative shift of the d-band center offers a reasonable descriptor for enhancing the electrocatalytic activity. In this study, the construction of Ni-incorporating RuO2 porous nanospheres is proposed as the cathode catalyst to demonstrate the hypothesis. Density functional theory calculations reveal that the introduction of Ni atoms can effectively modulate the surface electron structure of RuO2 and the adsorption capacities of oxygen-containing intermediates, accelerating charge transfer between them and optimizing the growth pathway of discharge products. Resultantly, the LOBs exhibit a large discharge specific capacity of 19658 mA h g-1 at 200 mA g-1 and extraordinary cycle life of 791 cycles. This study confers the concept of d-band center modulation for efficient and durable cathode catalysts of LOBs.

7.56-W continuous-wave Pr3+-based green laser via managing thermally induced effects

Blue-laser-diode-pumped Pr3+-based continuous-wave (CW) green lasers have aroused growing research interest in developing optoelectronic applications and deep ultraviolet laser sources due to their simple and compact structural design. However, the obstacle of thermally induced effects limits the available output power of Pr3+-based green lasers. Herein, combined with the theoretical analysis and experimental feedback, we effectively adjust the heat distribution inside the Pr3+:LiYF4 gain crystal by optimizing the crystal dimension and doping concentration. The excellent mode matching between the pump and green lasers is achieved under the consideration of thermally induced effects, yielding a maximum CW output power of 7.56 W. To the best of our knowledge, this is the largest output power of Pr3+-based CW green lasers so far. Moreover, the obtained green laser demonstrates excellent output stability (RMS = 1.27%) and beam quality (M2 = 1.30 × 1.12) under the lasing operation state with the maximum output power. We hope that this study can provide a feasible paradigm for developing blue-laser-diode-pumped visible lasers, especially for high-power lasers.

Monitoring and spatial traceability of river water quality using Sentinel-2 satellite images

Due to limited monitoring stations along rivers, it is difficult to trace the specific locations of high pollution areas along the whole river by traditionally in situ measurement. High-spatiotemporal-resolution Sentinel-2 satellite images make it possible to routinely monitor and trace the spatial distributions of river water quality if reliable retrieval algorithms are available. This study took seven major rivers (Qiantang River (QTR), Cao'e River (CEJ), Yongjiang River (YJ), Jiaojiang River (JJ), Oujiang River (OJ), Feiyun River (FYR), and Aojiang River (AJ)) in Zhejiang Province, China, as examples to illustrate the spatial traceability of river water quality parameters (permanganate index (COD_Mn), total phosphorus (TP), and total nitrogen (TN)) from Sentinel-2 satellite images. The regional retrieval models established for these parameters (COD_Mn, TP and TN) provided correlation coefficients (R) of 0.68, 0.78, and 0.7, respectively. Based on these models, time-series COD_Mn, TP, and TN products were obtained for the seven rivers from 2016 to 2021 from Sentinel-2 satellite images, and the results show that the COD_Mn, TP and TN were high downstream and low upstream; exceptions the CEJ, which was slightly higher in the middle reach than other reaches, and the TN in YJ, which was higher upstream than downstream. The downstream reaches were the main areas suffering from relatively high values in most seasons. Except for the springtime TN level in CEJ where the high TN areas were located along the middle reaches. In summer and autumn, the high TN areas in JJ, OJ, and AJ were located along the middle and lower reaches, and the TN in YJ was highest in the upstream. More importantly, this study revealed that the specific locations of high pollution areas along rivers can be effectively traced using Sentinel-2 satellite images, which would be helpful for precise water quality control of rivers.

A General Strategy for Ordered Carrier Transport of Quasi-2D and 3D Perovskite Films for Giant Self-Powered Photoresponse and Ultrahigh Stability

Organic-inorganic hybrid perovskite materials have been focusing more attention in the field of self-powered photodetectors due to their superb photoelectric properties. However, a universal growth approach is required and challenging to realize vertically oriented growth and grain boundary fusion of 2D and 3D perovskite grains to promote ordered carrier transport, which determines superior photoresponse and high stability. Herein, a general thermal-pressed (TP) strategy is designed to solve the above issues, achieving uniaxial orientation and single-grain penetration along the film thickness direction. It constructs the efficient channel for ordered carrier transport between two electrodes. Combining of the improved crystal quality and lower trap-state density, the quasi-2D and 3D perovskite-based self-powered photodetector devices (with/without hole transport layer) all exhibit giant and stable photoresponse in a wide spectrum range and specific wavelength laser. For the MAPbI3-based self-powered photodetectors, the largest Rλ value is as high as 0.57 A W-1 at 760 nm, which is larger than most reported results. Meanwhile, under laser illumination (532 nm), the FPEA2MA4Pb5I16-based device exhibits a high responsivity (0.4 A W-1) value, which is one of the best results in 2DRP self-powered photodetectors. In addition, fast response, ultralow detection limit, and markedly improved humidity, optical and heat stabilities are clearly demonstrated for these TP-based devices.

High-Performance and Self-Powered X-Ray Detectors Made of Smooth Perovskite Microcrystalline Films with 100-μm Grains

Perovskite single crystals and polycrystalline films have complementary merits and deficiencies in X-ray detection and imaging. Herein, we report preparation of dense and smooth perovskite microcrystalline films with both merits of single crystals and polycrystalline films through polycrystal-induced growth and hot-pressing treatment (HPT). Utilizing polycrystalline films as seeds, multi-inch-sized microcrystalline films can be in-situ grown on diverse substrates with maximum grain size reaching 100 μm, which endows the microcrystalline films with comparable carrier mobility-lifetime (μτ) product as single crystals. As a result, self-powered X-ray detectors with impressive sensitivity of 6.1 × 104 μC Gyair-1 cm-2 and low detection limit of 1.5 nGyair s-1 are achieved, leading to high-contrast X-ray imaging at an ultra-low dose rate of 67 nGyair s-1. Combining with the fast response speed (186 μs), this work may contribute to the development of perovskite-based low-dose X-ray imaging.

Measurement of the ^{18}O(α, γ)^{22}Ne Reaction Rate at JUNA and Its Impact on Probing the Origin of SiC Grains

The ^{18}O(α,γ)^{22}Ne reaction is critical for AGB star nucleosynthesis due to its connection to the abundances of several key isotopes, such as ^{21}Ne and ^{22}Ne. However, the ambiguous resonance energy and spin-parity of the dominant 470 keV resonance leads to substantial uncertainty in the ^{18}O(α,γ)^{22}Ne reaction rate for the temperature of interest. We have measured the resonance energies and strengths of the low-energy resonances in ^{18}O(α,γ)^{22}Ne at the Jinping Underground Nuclear Astrophysics experimental facility (JUNA) with improved precision. The key 470 keV resonance energy has been measured to be E_{α}=474.0±1.1  keV, with such high precision achieved for the first time. The spin-parity of this resonance state is determined to be 1^{-}, removing discrepancies in the resonance strengths in earlier studies. The results significantly improve the precision of the ^{18}O(α,γ)^{22}Ne reaction rates by up to about 10 times compared with the previous data at typical AGB temperatures of 0.1-0.3 GK. We demonstrate that such improvement leads to precise ^{21}Ne abundance predictions, with an impact on probing the origin of meteoritic stardust SiC grains from AGB stars.

Deep Underground Laboratory Measurement of ^{13}C(α,n)^{16}O in the Gamow Windows of the s and i Processes

The ^{13}C(α,n)^{16}O reaction is the main neutron source for the slow-neutron-capture process in asymptotic giant branch stars and for the intermediate process. Direct measurements at astrophysical energies in above-ground laboratories are hindered by the extremely small cross sections and vast cosmic-ray-induced background. We performed the first consistent direct measurement in the range of E_{c.m.}=0.24 to 1.9 MeV using the accelerators at the China Jinping Underground Laboratory and Sichuan University. Our measurement covers almost the entire intermediate process Gamow window in which the large uncertainty of the previous experiments has been reduced from 60% down to 15%, eliminates the large systematic uncertainty in the extrapolation arising from the inconsistency of existing datasets, and provides a more reliable reaction rate for the studies of the slow-neutron-capture and intermediate processes along with the first direct determination of the alpha strength for the near-threshold state.

Electron-Injection and Atomic-Interface Engineering toward Stabilized Defected 1T-Rich MoS2 as High Rate Anode for Sodium Storage

1T-phase MoS₂ is a promising electrode material for electrochemical energy storage due to its metallic conductivity, abundant active sites, and high theoretical capacity. However, because of the habitual conversion of metastable 1T to stable 2H phase via restacking, the poor rate capacity and cycling stability at high current densities hamper their applications. Herein, a synergetic effect of electron-injection engineering and atomic-interface engineering is employed for the formation and stabilization of defected 1T-rich MoS₂ nanoflowers. The 1T-rich MoS₂ and carbon monolayers are alternately intercalated with each other in the nanohybrids. The metallic 1T-phase MoS₂ and conductive carbon monolayers are favorable for charge transport. The expanded interlayer spacing ensures fast electrolyte diffusion and the decrease of the ion diffusion barrier. The obtained defected 1T-rich MoS₂/m-C nanoflowers exhibit high Na-storage capacity (557 mAh g^-1 after 80 cycles at 0.1 A g^-1), excellent rate capacity (411 mAh g^-1 at 10 A g^-1), and long-term cycling performance (364 mAh g^-1 after 1000 cycles at 2 A g^-1). Furthermore, a Na-ion full cell composed of the 1T-rich MoS₂/m-C anode and Na₃V₂(PO₄)₃/C cathode maintains excellent cycling stability at 0.5 A g^-1 during 400 cycles. Theoretical calculations are also performed to evaluate the phase stability, electronic conductivity, and Na⁺ diffusion behavior of 1T-rich MoS₂/m-C. The energy storage performance demonstrates its excellent application prospects.

Comparative Mitogenomic Analyses of Hydropsychidae Revealing the Novel Rearrangement of Protein-Coding Gene and tRNA (Trichoptera: Annulipalpia)

Gene rearrangement of the mitochondrial genome of insects, especially the rearrangement of protein-coding genes, has long been a hot topic for entomologists. Although mitochondrial gene rearrangement is common within Annulipalpia, protein-coding gene rearrangement is relatively rare. As the largest family in Annulipalpia, the available mitogenomes from Hydropsychidae Curtis, 1835 are scarce, and thus restrict our interpretation of the mitogenome characteristic. In this study, we obtained 19 novel mitogenomes of Hydropsychidae, of which the mitogenomes of the genus Arctopsyche are published for the first time. Coupled with published hydropsychid mitogenome, we analyzed the nucleotide composition evolutionary rates and gene rearrangements of the mitogenomes among subfamilies. As a result, we found two novel gene rearrangement patterns within Hydropsychidae, including rearrangement of protein-coding genes. Meanwhile, our results consider that the protein-coding gene arrangement of Potamyia can be interpreted by the tandem duplication/random loss (TDRL) model. In addition, the phylogenetic relationships within Hydropsychidae constructed by two strategies (Bayesian inference and maximum likelihood) strongly support the monophyly of Arctopscychinae, Diplectroninae, Hydropsychinae, and Macronematinae. Our study provides new insights into the mechanisms and patterns of mitogenome rearrangements in Hydropsychidae.

Direct measurement of the 19F(p, αγ)16O reaction in JUNA

The 19F(p, αγ)16O reaction is of crucial importance for Galactic 19F abundances and CNO cycle loss in first generation Population III stars. Due to its extremely small cross sections, the 19F(p, αγ)16O reaction has not been measured in the low energy part of the Gamow window(70-200 keV). As a day-one campaign, the experiment was performed under the extremely low cosmicray-induced background environment of the China JinPing Underground Laboratory(CJPL), one of the deepest underground laboratories in the world. The γ-ray yields were measured over Ec.m. =72.4–344 keV, covering the full Gamow window for the first time. The direct experimental data will help people to expound the fluorine over-abundances, energy generation, as well as heavy-element nuclosynthesis scenario in asymptotic giant branch (AGB) stars, with the astrophysical model on the firm ground.

Measurement of the 18O(α, γ)22Ne resonances at JUNA

22Ne(α,n)25Mg is one of the main neutron sources of the s process. 22Ne is produced by the 14N(α, γ)18F(β+)18O(α, γ)22Ne reaction chain in the helium burning, thus, the production rate of 22Ne is dominated by 14N(α,γ)18F and 18O(α,γ)22Ne. At the astrophysical relevant temperatures, the 18O(α,γ)22Ne reaction rates are determined by several low-energy resonances. In this work, the 18O(α,γ)22Ne reaction was measured at the 400 kV accelerator of Jinping Underground Nuclear Astrophysics experiment (JUNA). The γ-ray yields of the resonances between 470 to 770 keV were obtained.

Measurement of the low energy 25Mg(p,γ)26Al resonances

The cosmic 1.809 MeV γ-ray emitted by the radioactive nucleus 26Al in the Galaxy is one of the key observation targets of the γ-ray astronomy. The 26Al is mainly produced by the 25Mg(p,γ)26Al reaction in the stellar Mg-Al reaction cycle. At the astrophysical relevant temperatures, the reaction rates of 25Mg(p,γ)26Al are dominated by several narrow resonances at low energy. This work reports a measurement of the low energy 25Mg(p,γ)26Al resonances at Jinping Underground Nuclear Astrophysics experimental facility (JUNA) in the China Jinping Underground Laboratory (CJPL).

Commissioning of Underground Nuclear Astrophysics Experiment JUNA in China

Underground Nuclear Astrophysics Experiment in China (JUNA) has been commissioned by taking the advantage of the ultra-low background in Jinping underground lab. High current mA level 400 KV accelerator with an ECR source and BGO detectors were commissioned. JUNA studies directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. In the first quarter of 2021, JUNA performed the direct measurements of 25Mg(p,γ)26Al, 19F(p,α)16O, 13C(α,n)16O and 12C(α,γ)16O near the Gamow window. The experimental results reflect the potential of JUNA with higher statistics, precision and sensitivity of the data. The preliminary results of JUNA experiment and future plan are given.

Pressure-Enhanced Vertical Orientation and Compositional Control of Ruddlesden-Popper Perovskites for Efficient and Stable Solar Cells and Self-Powered Photodetectors

It is well-known that two-dimensional Ruddlesden-Popper (2DRP) perovskite has higher stability than three-dimensional counterparts. However, fundamental issues still exist in the vertical orientation and phase composition as well as phase distribution. Here, obvious control of the film quality of 2DRP PEA₂MA₄Pb₅I₁₆ (n = 5) perovskite is demonstrated via a thermal-pressed (TP) effect. The crystallinity, morphology, phase composition, and optoelectronic features unequivocally illustrate that the TP effect achieves a larger gain size, a smoother surface, an effectively vertical orientation, a relatively pure phase with a large n value, a gradient distribution of quantum wells, and enhanced interlayer interaction. These film and interface features lead to markedly enhanced charge transport/extraction and lower trap density. Accordingly, the TP-based perovskite film device delivers a power conversion efficiency of 15.14%, far higher than that of the control film device (11.10%) because of significant improvements in open-circuit voltage and short-circuit current. More importantly, it also presents excellent hydrophobicity, illumination stability, and environmental stability. In addition, the 2D perovskite self-powered photodetector also exhibits high responsivity (0.25 A W^-1) and specific detectivity (1.4 × 10¹² Jones) at zero bias.

Direct Measurement of the Astrophysical ^{19}F(p,αγ)^{16}O Reaction in the Deepest Operational Underground Laboratory

Fluorine is one of the most interesting elements in nuclear astrophysics, where the ^{19}F(p,α)^{16}O reaction is of crucial importance for Galactic ^{19}F abundances and CNO cycle loss in first generation Population III stars. As a day-one campaign at the Jinping Underground Nuclear Astrophysics experimental facility, we report direct measurements of the essential ^{19}F(p,αγ)^{16}O reaction channel. The γ-ray yields were measured over E_{c.m.}=72.4-344  keV, covering the Gamow window; our energy of 72.4 keV is unprecedentedly low, reported here for the first time. The experiment was performed under the extremely low cosmic-ray-induced background environment of the China JinPing Underground Laboratory, one of the deepest underground laboratories in the world. The present low-energy S factors deviate significantly from previous theoretical predictions, and the uncertainties are significantly reduced. The thermonuclear ^{19}F(p,αγ)^{16}O reaction rate has been determined directly at the relevant astrophysical energies.

Effect of glucocorticoids infiltration on CRSwNP after endoscopic sinus surgery and the curative efficacy of nasal ventilation function and mucociliary clearance

OBJECTIVES

This study investigated and analyzed the effects of glucocorticoid infiltration on chronic rhino-sinusitis with nasal polyps (CRSwNP) after endoscopic sinus surgery (ESS) and its curative efficacy on nasal ventilation function and mucociliary clearance (MCC).

METHODS

126 CRSwNP patients admitted to the hospital from March 2018 to May 2020 were enrolled and randomly divided into observation group (n=65) and control group (n=61) based on random number table. The control group received ESS, and the observation group was given glucocorticoids treatment after ESS. The changes of nasal ventilation function, MCC and quality of life between the two groups of patients before and after treatment were compared.

RESULTS

The overall effective rate of clinical therapy was critically higher in observation group than in control group (P<0.05). In addition, NMCA and NCV in observation group were critically higher than those in control group (P<0.05), and nasal airway resistance (NAR) in observation group was notably lower than that in control group (P<0.05). In addition, the Saccharin removal time in observation group after treatment was remarkably lower than that in control group (P<0.05), while the speed and rate of MCC were critically higher than those in control group (P<0.05). Finally, the scores of each dimension of WHOQOL-100 scale in two groups of subjects after treatment were critically higher than those before treatment (P<0.05), and the scores in observation group were notably higher than those in control group (P<0.05).

CONCLUSION

The treatment of glucocorticoid infiltration on CRSwNP after ESS can effectively improve the curative effect. It improves the patient's function of nasal ventilation and MCC, thus beneficial to promoting the sufferers' living quality and is worthy of clinical promotion.

MAPbI3 Quasi-Single-Crystal Films Composed of Large-Sized Grains with Deep Boundary Fusion for Sensitive Vis-NIR Photodetectors

Perovskite single-crystal (SC) or quasi-single-crystal (QSC) films are promising candidates for excellent performance of photoelectric devices. However, it is still a great challenge to fabricate large-area continuous SC or QSC films with proper thickness. Herein, we propose a pressure-assisted high-temperature solvent-engineer (PTS) strategy to grow large-area continuous MAPbI₃ QSC films with uniformly thin thickness and orientation. Dramatic grain growth (∼100 μm in the lateral dimension) and adequate boundary fusion are realized in them, vastly eliminating the grain boundaries. Thus, remarkable diminution of the trap density (n_trap: 7.43 × 10¹¹ cm^-3) determines a long carrier lifetime (τ₂: 1.7 μs) and superior photoelectric performance of MAPbI₃-based lateral photodetectors; for instance, an ultrahigh on/off ratio (>2.4 × 10⁶, 2 V), great stability, fast response (283/306 μs), and high detectivity (1.41 × 10¹³) are achieved. The combination properties and performance of the QSC films surpass most of the reported MAPbI₃. This effective approach in growing perovskite QSC films points out a novel way for perovskite-based optoelectronic devices with superior performance.

Constraining the External Capture to the ^{16}O Ground State and the E2 S Factor of the ^{12}C(α,γ)^{16}O Reaction

The ^{12}C(α,γ)^{16}O reaction is one of the most crucial reactions in nuclear astrophysics. The E2 external capture to the ^{16}O ground state (GS) has not been emphasized in previous analyses but may make a significant contribution to the ^{12}C(α,γ)^{16}O cross section depending on the value of the GS asymptotic normalization coefficient (ANC). In the present work, we determine this ANC to be 337±45  fm^{-1/2} through the ^{12}C(^{11}B,^{7}Li)^{16}O reaction using a high-precision magnetic spectrograph. This sheds light on the existing large discrepancy of more than 2 orders of magnitude between the previously reported ANC values. Based on the new ANC, we experimentally constrain the GS external capture and show that through interference with the high energy tail of the 2^{+} subthreshold state, a substantial enhancement in the GS S_{E2}(300) factor can be obtained (70±7  keV b) compared to that of a recent review (45 keV b), resulting in an increase of the total S factor from 140 to 162 keV b, which is now in good agreement with the value obtained by reproducing supernova nucleosynthesis calculations with the solar-system abundances. This work emphasizes that the external capture contribution for the ground state transition cannot be neglected in future analyses of the ^{12}C(α,γ)^{16}O reaction.

Solvent-Assisted Thermal-Pressure Strategy for Constructing High-Quality CH3NH3PbI3- xCl x Films as High-Performance Perovskite Photodetectors

High-quality CH₃NH₃PbI_3-xCl _x films have attracted research interests in photoelectric devices because of their improved carrier diffusion length and charge mobility. Herein, a solvent-assisted thermal-pressure strategy is developed to promote the secondary growth of perovskite grains in the films. Highly oriented perovskite films are then obtained with large-sized grains (5-10 μm). As a consequence, the photodetectors based on the high-quality CH₃NH₃PbI_{3- x}Cl _x films exhibit enhanced ophtoelectrical performance, including high on/off ratio (>2.1 × 10⁴), fast response time (54/63 μs), and high detectivity (∼1.3 × 10¹²). This work suggests an effective approach for high-quality perovskite films, which will be promising candidates for other high-efficiency photoelectric devices.

High-Quality CH3NH3PbI3 Films Obtained via a Pressure-Assisted Space-Confined Solvent-Engineering Strategy for Ultrasensitive Photodetectors

High-quality organic-inorganic hybrid perovskite films are crucial for excellent performance of photoelectric devices. Herein, we demonstrate a pressure-assisted space-confined solvent-engineering strategy to grow highly oriented, pinhole-free thin films of CH₃NH₃PbI₃ with large-scale crystalline grains, high smoothness, and crystalline fusion on grain boundaries. These single-crystalline grains vertically span the entire film thickness. Such a film feature dramatically reduces recombination loss and then improves the transport property of charge carriers in the films. Consequently, the photodetector devices, based on the high-quality CH₃NH₃PbI₃ films, exhibit high photocurrent (105 μA under 671 nm laser with a power density of 20.6 mW/cm² at 10 V), good stability, and, especially, an ultrahigh on/off ratio (I_light/I_dark > 2.2 × 10⁴ under an incident light of 20.6 mW/cm²). These excellent performances indicate that the high-quality films will be potential candidates in other CH₃NH₃PbI₃-based photoelectric devices.

Sn-Doped Rutile TiO2 Hollow Nanocrystals with Enhanced Lithium-Ion Batteries Performance

Hollow structures and doping of rutile TiO₂ are generally believed to be effective ways to enhance the performance of lithium-ion batteries. Herein, uniformly distributed Sn-doped rutile TiO₂ hollow nanocrystals have been synthesized by a simple template-free hydrothermal method. A topotactic transformation mechanism of solid TiOF₂ precursor is proposed to illustrate the formation of rutile TiO₂ hollow nanocrystals. Then, the Sn-doped rutile TiO₂ hollow nanocrystals are calcined and tested as anode in the lithium-ion battery. They deliver a highly reversible specific capacity of 251.3 mA h g^-1 at 0.1 A g^-1 and retain ∼110 mA h g^-1 after 500 cycles at a high current rate 5 A g^-1 (30 C), which is much higher than most of the reported work.

A CH3NH3PbI3 film for a room-temperature NO2 gas sensor with quick response and high selectivity

A room-temperature NO₂ gas sensor with excellent performances is fabricated using an MAPbI₃ (MA = CH₃NH₃⁺) thin film.

Ultrafast Molecular Stitching of Graphene Films at the Ethanol/Water Interface for High Volumetric Capacitance

Compact graphene film electrodes with a high ion-accessible surface area have the promising potential to realize high-density electrochemical energy storage (or high volumetric capacitance), which is vital for the development of flexible, portable, and wearable energy storage devices. Here, a novel, ultrafast strategy for stitching graphene sheets into films, in which p-phenylenediamine (PPD) molecules are uniformly intercalated between the graphene sheets, is simply constructed at the ethanol/water interface. Due to uniformly interlayer spacing (∼1.1 nm), good wettability, and an interconnected ion transport channel, the binder-free PPD-graphene film with a high packing density (1.55 g cm^-3) delivers an ultrahigh volumetric capacitance (711 F cm^-3 at a current density of 0.5 A g^-1), high rate performance, high power and energy densities, and excellent cycling stability in aqueous electrolytes. This interfacial stitching strategy holds new promise for the future design of enhanced electrochemical energy-storage devices.

Ultrathin TiO2nanosheets synthesized using a high pressure solvothermal method and the enhanced photoresponse performance of CH3NH3PbI3–TiO2composite films

Highly crystalline ultrathin (2–3 nm) TiO₂nanosheets are synthesized using a high pressure solvothermal method. The perovskite–TiO₂films exhibit strikingly enhanced photoresponse performance.

Growth of Large-Size SnS Thin Crystals Driven by Oriented Attachment and Applications to Gas Sensors and Photodetectors

Freestanding large-size SnS thin crystals are synthesized via two-dimensional oriented attachment (OA) growth of colloidal quantum dots (CQDs) in a novel high-pressure solvothermal reaction. The SnS thin crystals present a uniform rectangular shape with a lateral size of 20-30 um and thickness of <10 nm. The evolution process demonstrates that a synergetic effect of pressure, aging time and organic ligands results in polycrystal-to-monocrystal formation and defect annihilation. Furthermore, gas sensor and photodetector devices, based on SnS thin single crystals, are also prepared. The sensing devices present high sensitivity, superior selectivity, low detection limit (≪100 ppb) and reversibility to NO2 at room temperature. The fabricated photodetector devices exhibit a high responsivity of 2.04 × 10(3) A W(1-) and high external quantum efficiency of ∼4.75 × 10(5) % at 532 nm, which are much higher than most of the photodetector devices.

Synthesis of Few-Atomic-Layer BN Hollow Nanospheres and Their Applications as Nanocontainers and Catalyst Support Materials

In this work, few-atomic-layer boron nitride (BN) hollow nanospheres were directly synthesized via a modified CVD method followed by subsequent high-temperature degassing treatment. The encapsulated impurities in the hollow nanospheres were effectively removed during the reaction process. The BN shells of most nanospheres consisted of 2-6 atomic layers. Because of the low thickness, the obtained BN hollow nanospheres presented excellent performance in many aspects. For instance, they were demonstrated as useful nanocontainers for controllable multistep release of iodine, which could diffuse and be encapsulated into the few-layer BN hollow nanospheres when heating. They were also promising support materials that could markedly increase the photocatalytic activity of TiO2 nanocrystals.

Pressure-Induced Oriented Attachment Growth of Large-Size Crystals for Constructing 3D Ordered Superstructures

Oriented attachment (OA), a nonclassical crystal growth mechanism, provides a powerful bottom-up approach to obtain ordered superstructures, which also demonstrate exciting charge transmission characteristic. However, there is little work observably pronouncing the achievement of 3D OA growth of crystallites with large size (e.g., submicrometer crystals). Here, we report that SnO2 3D ordered superstructures can be synthesized by means of a self-limited assembly assisted by OA in a designed high-pressure solvothermal system. The size of primary building blocks is 200-250 nm, which is significantly larger than that in previous results (normally <10 nm). High pressure plays the key role in the formation of 3D configuration and fusion of adjacent crystals. Furthermore, this high-pressure strategy can be readily expanded to additional materials. We anticipate that the welded structures will constitute an ideal system with relevance to applications in optical responses, lithium ion battery, solar cells, and chemical sensing.

A positive synergetic effect observed in the P3HT–SnO2 composite semiconductor: the striking increase of carrier mobility

A P3HT–SnO₂ PNS composite semiconductor with extra-high mobility was prepared via the positive synergetic effect between organic and inorganic moieties.

Large-Scale Synthesis of Few-Layer F-BN Nanocages with Zigzag-Edge Triangular Antidot Defects and Investigation of the Advanced Ferromagnetism

Investigation of light-element magnetism system is essential in fundamental and practical fields. Here, few-layer (∼3 nm) fluorinated hexagonal boron nitride (F-BN) nanocages with zigzag-edge triangular antidot defects were synthesized via a facile one-step solid-state reaction. They are free of metallic impurities confirmed by X-ray photoelectron spectroscopy, electron energy loss spectroscopy, and inductively coupled plasma atomic emission spectroscopy. Ferromagnetism is obviously observed in the BN nanocages. Saturation magnetization values of them differed by less than 7% between 5 and 300 K, indicating that the Curie temperature (Tc) was much higher than 300 K. By adjusting the concentration of triangular antidot defects and fluorine dopants, the ferromagnetic performance of BN nanocages could be effectively varied, indicating that the observed magnetism originates from triangular antidot defects and fluorination. The corresponding theoretical calculation shows that antidot defects and fluorine doping in BN lattice both favor spontaneous spin polarization and the formation of local magnetic moment, which should be responsible for long-range magnetic ordering in the sp material.

[The expression and significance of chemokines eotaxin and RANTES in the rat model of allergic rhinitis]

OBJECTIVE

To explore the expression and significance of Eotaxin and RANTES in the rat model of allergic rhinitis (AR).

METHOD

20 female SD rats in 6-7 weeks were randomly divided into control group and AR group (n = 10, respectively). AR rat model was made with ovalbumin stimulation. To detect pathological changes in mucosa and chemokine Eotaxin, RANTES in their nasal and lung tissues after execution.

RESULT

Compared with the control group, Lung EOS cell counted higher in AR group and the difference was significant (P < 0.01); the AR rats nasal mucosa and lung tissue of Eotaxin, RANTES expression was significantly increased (P < 0.01).

CONCLUSION

There exist high expression of Eotaxin, RANTES, infiltration of eosinophils in nasal and lung tissue of model rats with allergic rhinitis, inferring that the upper and lower respiratory tract inflammatory response has obvious consistency.

Reaction of Hexagonal Boron Nitride Nano-crystals under Mild Hydrothermal Conditions

The reaction between hexagonal boron nitride (hBN) nano-crystals and water at low temperature and low pressure has been investigated. The results reveal that this reaction can be greatly promoted by increasing the hot-pressing temperature. However, when the temperature is above 280 °C, the reaction is too fast to be controlled by varying the hot-pressing pressure and time. On the other hand, stress and defects are induced in hBN nano-crystals by the hydrothermal hot-pressing process, resulting in a shift of the IR absorption bands and a deterioration of crystalline perfection. These results may be useful for synthesizing cBN by the hydrothermal method and converting hBN nanocrystals into cBN under moderate conditions.

Boron nitride ultrathin fibrous nanonets: one-step synthesis and applications for ultrafast adsorption for water treatment and selective filtration of nanoparticles

Novel boron nitride (BN) ultrathin fibrous networks are firstly synthesized via an one-step solvothermal process. The average diameter of BN nanofibers is only ~8 nm. This nanonets exhibit excellent performance for water treatment. The maximum adsorption capacity for methyl blue is 327.8 mg g(-1). Especially, they present the property of ultrafast adsorption for dye removal. Only ~1 min is enough to almost achieve the adsorption equilibrium. In addition, the BN fibrous nanonets could be applied for the size-selective separation of nanoparticles via a filtration process.

Low-temperature solid state synthesis and in situ phase transformation to prepare nearly pure cBN

Cubic boron nitride (cBN) is synthesized by a low-temperature solid state synthesis and in situ phase transformation route with NH(4)BF(4), B, NaBH(4) and KBH(4) as the boron sources and NaN(3) as the nitrogen source. Furthermore, two new strategies are developed, i.e., applying pressure on the reactants during the reaction process and introducing the structural induction effect. These results reveal that the relative contents of cBN are greatly increased by applying these new strategies. Finally, almost pure cBN (∼90%) crystals are obtained by reacting NH(4)BF(4) and NaN(3) at 250 °C and 450 MPa for 24 h, with NaF as the structural induction material. The heterogeneous nucleation mechanism can commendably illuminate the structure induction effect of NaF with face center cubic structure. In addition, the induction effect results in the cBN nanocrystals presenting obvious oriented growth of {111} planes.

[Treatment of maxillary cyst with endoscopic fenestration in nasal bottom]

OBJECTIVE

To explore the feasibility of treatment of maxillary cyst with only fenestration in nasal bottom by nasal endoscope.

METHOD

Eighteen patients with maxillary cyst manifested with facial swelling or hard palate bulging were diagnosed by CT scan and needle aspiration biopsy, and then underwent cystic fenestration operations with the tooth in cyst kept intact.

RESULT

After over 2 years follow-up with endoscope (partly CT scanned), recurrent infection was not noticed in all cases, contour of maxilla was well preserved with ostium patent and cystic cavity markedly shrinks.

CONCLUSION

Endoscopic fenestration in nasal bottom only is a safe, reliable, and effective procedure in the treatment of maxillary cyst.