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Yan H, He B, Zhao R, Ren W, Suo Z, Xu Y, Zhang Y, Bai C, Yan H, Liu R. Electrochemical aptasensor based on Ce 3NbO 7/CeO 2@Au hollow nanospheres by using Nb.BbvCI-triggered and bipedal DNA walker amplification strategy for zearalenone detection. JOURNAL OF HAZARDOUS MATERIALS 2022; 438:129491. [PMID: 35785741 DOI: 10.1016/j.jhazmat.2022.129491] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Revised: 06/15/2022] [Accepted: 06/26/2022] [Indexed: 06/15/2023]
Abstract
Herein, an electrochemical aptasensor combining Nb.BbvCI-triggered bipedal DNA walking strategy was constructed for ultrasensitive assay of zearalenone (ZEN). The aptasensor used Ce3NbO7/CeO2 @Au hollow nanospheres as electrode modification material and PdNi@MnO2/MB as the signal label. Importantly, the Ce3NbO7/CeO2 synthesized by hydrothermal method were combined with Au nanoparticles and applied to the electrode surface. The as-prepared Ce3NbO7/CeO2 @Au possessed a large surface area, excellent electrical conductivity, stability and more binding sites. PdNi@MnO2 with high specific surface area and porosity combined with molecule methylene blue (MB) was introduced into electrodes as the signal label. The proposed aptasensor utilized the advantages of specific recognition of aptamers and target molecules to release bipedal DNA walker (w-DNA), and then the w-DNA was triggered by Nb.BbvCI and entered the cycle to release more signal probes. The feasibility of this strategy was recorded by the differential pulse voltammetry (DPV) method. Under the optimized conditions, the electrochemical aptasensor exhibited a wide linear dynamic range from 1 × 10-4 to 1 × 103 ng mL-1 with a low detection limit of 4.57 × 10-6 ng mL-1. Moreover, the aptasensor had high selectivity, good stability, excellent repeatability and provided an effective method for the trace detection of ZEN in real samples.
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Khare D, Majumdar S, Krishnamurthy S, Dubey AK. An in vivo toxicity assessment of piezoelectric sodium potassium niobate [Na xK 1-xNbO 3 (x = 0.2-0.8)] nanoparticulates towards bone tissue engineering approach. BIOMATERIALS ADVANCES 2022; 140:213080. [PMID: 35985067 DOI: 10.1016/j.bioadv.2022.213080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 07/26/2022] [Accepted: 08/08/2022] [Indexed: 06/15/2023]
Abstract
One of the recent challenges in the design/development of prosthetic orthopedic implants is to address the concern of local/systemic toxicity of debris particles, released due to wear or degradation. Such debris particles often lead to inflammation at the implanted site or aseptic loosening of the prosthesis which results in failure of the implant during long run. Several in vitro studies demonstrated the potentiality of piezoelectric sodium potassium niobate [NaxK1-xNbO3 (x = 0.2, 0.5, 0.8), NKN] as an emerging next-generation polarizable orthopedic implant. In this perspective, we performed an in vivo study to examine the local and systemic toxicity of NKN nanoparticulates, as a first report. In the present study, male Wistar rats were intra-articularly injected to the knee joint with 100 μl of NKN nanoparticulates (25 mg/ml in normal saline). After 7 days of exposure, the histopathological analyses demonstrate the absence of any inflammation or dissemination of nanoparticulates in vital organs such as heart, liver, kidney and spleen. The anti-inflammatory cytokines (IL-4 and IL-10) profile analyses suggest the increased anti-inflammatory response in the treated rats as compared to non-injected (control) rats, preferably for the sodium and potassium rich NKN i.e., Na0.8K0.2NbO3 and Na0.2K0.8NbO3. The biochemical analyses revealed no pathological changes in the liver and kidney of particulate treated rats. The present study is the first proof to confirm the non-toxic nature of NKN nanoparticulates which provides a step forward towards the development of prosthetic orthopedic implants using biocompatible piezoelectric NKN ceramics.
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Huang B, Liu Z, Wang Y, Zhou L, Wang C, Ye T. Release behavior and mechanism of uranium and thorium from Ta-Nb tailings under simulated rainfall in Jiangxi Province, China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:57466-57478. [PMID: 35352230 DOI: 10.1007/s11356-022-19931-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 03/23/2022] [Indexed: 06/14/2023]
Abstract
Tantalum-niobium ore belongs to associated radioactive ore, which is accompanied by a certain amount of radioactive uranium and thorium. The remaining slag is enriched with a large number of radionuclides; after weathering, natural rainfall, and surface water scouring, radioactive elements such as uranium, thorium, and some heavy metal elements are exposed or washed into the soil, which poses a threat to the ecological environment and human health. In this study, for characterization analysis during, before, and after leaching, dynamic simulation experiment was carried out on a Ta-Nb slag sample in Jiangxi, China. From SEM analysis, the soluble substances adsorbed on the slag surface dissolve into the solution after leaching in simulated rainfall, and the remained slag becomes smooth with different particle sizes. The XRD diffraction analysis of the sample showed that after leaching in simulated rainfall, the existing forms of elements are different. pH of the leachate of Ta-Nb slag is 1.79; Ta-Nb slag contains many rare metal elements, nonmetal elements, radioactive elements, and some salt compounds; and the content of thorium is higher than that of uranium by EDS analysis. The release of uranium and thorium is obviously affected by the amount of leachate and pH. Under the lower pH of leaching solution, the release of uranium and thorium is more effective. The results of Fick diffusion theory and Elovich equation show that the release and migration mode of uranium and thorium in Ta-Nb slag are mainly surface elution; under acidic conditions, the release and migration of uranium and thorium are faster. This study provides basic data and scientific information for solving the key problems of pollution control of associated radioactive waste in environmental protection.
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Wolski L, Sobańska K, Muńko M, Czerniak A, Pietrzyk P. Unraveling the Origin of Enhanced Activity of the Nb 2O 5/H 2O 2 System in the Elimination of Ciprofloxacin: Insights into the Role of Reactive Oxygen Species in Interface Processes. ACS APPLIED MATERIALS & INTERFACES 2022; 14:31824-31837. [PMID: 35816763 PMCID: PMC9305982 DOI: 10.1021/acsami.2c04743] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The overlooked role of reactive oxygen species (ROS), formed and stabilized on the surface of Nb2O5 after H2O2 treatment, was investigated in the adsorption and degradation of ciprofloxacin (CIP), a model antibiotic. The contribution of ROS to the elimination of CIP was assessed by using different niobia-based materials in which ROS were formed in situ or ex situ. The formation of ROS was confirmed by electron paramagnetic resonance (EPR) and Raman spectroscopy. The modification of the niobia surface charge by ROS was monitored with zeta potential measurements. The kinetics of CIP removal was followed by UV-vis spectroscopy, while identification of CIP degradation products and evaluation of their cytotoxicity were obtained with liquid chromatography-mass spectrometry (LC-MS) and microbiological studies, respectively. Superoxo and peroxo species were found to significantly improve the efficiency of CIP adsorption on Nb2O5 by modifying its surface charge. At the same time, it was found that improved removal of CIP in the dark and in the presence of H2O2 was mainly determined by the adsorption process. The enhanced adsorption was confirmed by infrared spectroscopy (IR), total organic carbon measurements (TOC), and elemental analysis. Efficient chemical degradation of adsorbed CIP was observed upon exposure of the Nb2O5/H2O2 system to UV light. Therefore, niobia is a promising inorganic adsorbent that exhibits enhanced sorption capacity toward CIP in the presence of H2O2 under dark conditions and can be easily regenerated in an environmentally benign way by irradiation with UV light.
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Chen J, Liu Y, Cheng G, Guo J, Du S, Qiu J, Wang C, Li C, Yang X, Chen T, Chen Z. Tailored Hydrogel Delivering Niobium Carbide Boosts ROS-Scavenging and Antimicrobial Activities for Diabetic Wound Healing. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2022; 18:e2201300. [PMID: 35678523 DOI: 10.1002/smll.202201300] [Citation(s) in RCA: 47] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 05/18/2022] [Indexed: 06/15/2023]
Abstract
The treatment of diabetic wounds remains challenging due to the excess levels of oxidative stress, vulnerability to bacterial infection, and persistent inflammation response during healing. The development of hydrogel wound dressings with ideal anti-inflammation, antioxidant, and anti-infective properties is an urgent clinical requirement. In the present study, an injectable thermosensitive niobium carbide (Nb2 C)-based hydrogel (Nb2 C@Gel) with antioxidative and antimicrobial activity is developed to promote diabetic wound healing. The Nb2 C@Gel system is composed of Nb2 C and a PLGA-PEG-PLGA triblock copolymer. The fabricated Nb2 C nanosheets (NSs) show good biocompatibility during in vitro cytotoxicity and hemocompatibility assays and in vivo toxicity assays. In vitro experiments show that Nb2 C NSs can efficiently eliminate reactive oxygen species (ROS), thus protecting cells in the wound from oxidative stress damage. Meanwhile, Nb2 C NSs also exhibit good near-infrared (NIR) photothermal antimicrobial activity against both Staphylococcus aureus and Escherichia coli. In vivo results demonstrate that Nb2 C@Gel promotes wound healing by attenuating ROS levels, reducing oxidative damage, eradicating bacterial infection under NIR irradiation, and accelerating angiogenesis. To summarize, the Nb2 C@Gel system, with its ROS-scavenging, photothermal antimicrobial and hemostatic activities, can be a promising and effective strategy for the treatment of diabetic wounds.
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Ju S, Zhang H, Kosinski JA. Improved Extraction of Second-Order Material Constants for Current Generation Y-Grown La₃Ga 5.5Nb 0.5O₁₄ (LGN) Crystal. IEEE TRANSACTIONS ON ULTRASONICS, FERROELECTRICS, AND FREQUENCY CONTROL 2022; 69:2137-2142. [PMID: 35404816 DOI: 10.1109/tuffc.2022.3166549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
With higher demand for sensor development, piezoelectric materials with advanced performance and wide availability draw more attention today. Accurate second-order material constants are necessary for modeling and mechanical design of sensors that make use of langanite (La3Ga5.5Nb0.5O14, LGN) crystals. We report here on room temperature LGN bulk acoustic wave (BAW) velocities obtained with reduced uncertainties using ultrasound measurements and taking advantage of the cross correlation signal processing technique, and a full set of LGN material constants extracted from the BAW velocity results. Our results compare favorably with prior results assessed as using a reliable measurement technique, and differ in expected fashion from other results based on techniques that do not address a known weakness in the measurement technique.
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Yoshioka K, Kurashina Y, Ogawa A, Asakura T. Effect of the area of a lithium niobate transducer on the efficiency of ultrasonic atomization driven by resonance vibration. ULTRASONICS SONOCHEMISTRY 2022; 86:106019. [PMID: 35504139 PMCID: PMC9065876 DOI: 10.1016/j.ultsonch.2022.106019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 04/23/2022] [Accepted: 04/26/2022] [Indexed: 06/14/2023]
Abstract
In recent years, individual control of one's personal environment has been drawing increasing attention due to the growing interest in health care. Wearable devices are especially useful because of their controllability regardless of location. Humidity is one of the inevitable factors in the personal environment as a preventive against infectious diseases. Although atomization devices are commonly used as a method of humidity control, at present, there are no wearable humidity control devices. Vibration of a lithium niobate (LN) device in the thickness mode is a promising piezoelectric method for miniaturization of atomization devices for humidity control. To miniaturize the atomization device, the transducer size needs to be small not so much as to decrease the atomization efficiency. However, the effect of the device area on the atomization efficiency of LN at a size suitable for mounting in wearable devices has not been studied. Here, we conducted an atomization demonstration of LN devices with different sizes to evaluate particle size and atomization efficiency. Furthermore, to reveal the relationship between vibration behavior and atomization efficiency, resonance vibration in the MHz frequency band was evaluated by the finite element method and an impedance analyzer. The results showed that the peak size of water particles atomized by each device was in the range of 3.2 to 4.2 µm, which is smaller than particles produced by typical piezoelectric ceramics. Moreover, the best LN size for efficient atomization was found to be 8 mm × 10 mm among the five LN device sizes used in experiments. From the relationship between vibration behavior and atomization efficiency, the size of the transducer was suggested to affect the vibration mode. The obtained result suggested that the LN device is suitable for small wearable nebulizer devices.
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Klopfer E, Dagli S, Barton D, Lawrence M, Dionne JA. High-Quality-Factor Silicon-on-Lithium Niobate Metasurfaces for Electro-optically Reconfigurable Wavefront Shaping. NANO LETTERS 2022; 22:1703-1709. [PMID: 35112873 DOI: 10.1021/acs.nanolett.1c04723] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Dynamically reconfigurable metasurfaces promise compact and lightweight spatial light modulation for many applications, including LiDAR, AR/VR, and LiFi systems. Here, we design and computationally investigate high-quality-factor silicon-on-lithium niobate metasurfaces with electrically driven, independent control of its constituent nanobars for full phase tunability with high tuning efficiency. Free-space light couples to guided modes within each nanobar via periodic perturbations, generating quality factors exceeding 30,000 while maintaining a bar spacing of <λ/1.5. We achieve nearly 2π phase variation with an applied bias not exceeding ±25 V, maintaining a reflection efficiency above 91%. Using full-field simulations, we demonstrate a high-angle (51°) switchable beamsplitter with a diffracted efficiency of 93% and an angle-tunable beamsteerer, spanning 18-31°, with up to 86% efficiency, all using the same metasurface device. Our platform provides a foundation for highly efficient wavefront-shaping devices with a wide dynamic tuning range capable of generating nearly any transfer function.
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Ouyang W, Zhou Y, Fei X, Bai Y, Wang H, Wu Z. Simultaneous removal of NO and dichloromethane (CH 2Cl 2) over Nb-loaded cerium nanotubes catalyst. J Environ Sci (China) 2022; 111:175-184. [PMID: 34949347 DOI: 10.1016/j.jes.2021.03.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 03/10/2021] [Accepted: 03/10/2021] [Indexed: 06/14/2023]
Abstract
Herein, a series of niobium oxide supported cerium nanotubes (CeNTs) catalysts with different loading amount of Nb2O5 (0-10 wt.%) were prepared and used for selective catalytic reduction of NOx with NH3 (NH3-SCR) in the presence of CH2Cl2. Commercial V2O5-WO3-TiO2 catalyst was also prepared for comparison. The physcial properties and chemical properties of the Nb2O5 loaded cerium nanotubes catalysts were investigated by X-ray diffractometer, Transmission electron microscope, Brunauer-Emmett-Teller specific surface area, H2-temperature programmed reduction, NH3-temperature programmed desorption and X-ray photoelectron spectroscopy. The experiment results showed that the loading amount of Nb2O5 had a significant effect on the catalytic performance of the catalysts. 10 wt.% Nb-CeNTs catalyst presented the best NH3-SCR performance and degradation efficiency of CH2Cl2 among the prepared catalysts, due to its superior redox capability, abundant surface oxygen species and acid sites, the interaction between Nb and Ce, higher ratio of Nb4+/(Nb5++ Nb4+) and Ce3+/(Ce3+ + Ce4+), as well as the special tubular structure of cerium nanotube. This study may provide a practical approach for the design and synthesis of SCR catalysts for the simultaneously removal NOx and chlorinated volatile organic compounds (CVOCs) emitted from the stationary industrial sources.
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Jawed SF, Rabadia CD, Azim F, Khan SJ. Effect of Nb on β → α ″ Martensitic Phase Transformation and Characterization of New Biomedical Ti-xNb-3Fe-9Zr Alloys. SCANNING 2021; 2021:8173425. [PMID: 34950283 PMCID: PMC8668309 DOI: 10.1155/2021/8173425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Accepted: 11/15/2021] [Indexed: 06/14/2023]
Abstract
A new generation of Ti-xNb-3Fe-9Zr (x = 15, 20, 25, 30, 35 wt %) alloys have been designed using various theoretical approaches including DV-xα cluster, molybdenum equivalency, and electron to atom ratio. Afterward, designed alloys are fabricated using cold crucible levitation melting technique. The microstructure and mechanical performances of newly designed alloys are characterized in this work using scanning electron microscope and universal testing machine, respectively. Each alloy demonstrates monolithic β phase except Ti-35Nb-3Fe-9Zr alloy which display dual α ″ + β phases. Typically, niobium acts as an isomorphous beta stabilizer. However, in this work, formation of martensitic α ″ phases occurs at 35 wt % of niobium among the series of newly designed alloys. Furthermore, none of the alloys fail till the maximum load capacity of machine, i.e., 100 KN except Ti-35Nb-3Fe-9Zr alloy. Moreover, the Vickers hardness test is carried out on Ti-xNb-3Fe-9Zr alloys which demonstrate slip bands around the indentation for each alloy. Notably, the deformation bands and cracks around the indentations of each alloy have been observed using optical microscopy; Ti-35Nb-3Fe-9Zr demonstrates some cracks along with slip bands around its indentation. The Ti-25Nb-3Fe-9Zr alloy shows the highest yield strength of 1043 ± 20 MPa, large plasticity of 32 ± 0.5%, and adequate hardness of 152 ± 3.90 Hv among the investigated alloys. The Ti-25Nb-3Fe-9Zr alloy demonstrates good blend of strength and malleability. Therefore, Ti-25Nb-3Fe-9Zr can be used effectively for the biomedical applications.
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de Jesus ET, Moreira AJ, Sá MC, Freschi GPG, Joya MR, Li MS, Paris EC. Potential of Nb 2O 5 nanofibers in photocatalytic degradation of organic pollutants. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:69401-69415. [PMID: 34302247 DOI: 10.1007/s11356-021-15435-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Accepted: 07/09/2021] [Indexed: 06/13/2023]
Abstract
Various photocatalytic nanomaterials for environmental remediation have been promoted due to the pollution caused by different organic pollutants. In this study, Nb2O5 nanofibers were obtained by electrospinning technique, presenting controlled crystallinity and high specific surface area to improve the photoactivity response. The structural characterization indicated Nb2O5 nanofibers with orthorhombic phase formation. The photoluminescence measurements showed different energy levels contributing to the electronic transition events. The nanofibers with a bandgap up to 3.6 eV were applied to photocatalysis of dyes (rhodamine B (RhB) or methylene blue (MB)) and fluoxetine (FLX), listed as an emergent pollutant. In the optimized condition (pH = 9), the RhB and MB photocatalysis was 59% and 93% more efficient than photolysis due to ζ = - 50 mV ± 5 for EtOH_550 sample increased interaction with MB (cationic) compared to RhB unprotonated (pKa = 3.7). Therefore, FLX (pKa = 10.7) was selected due to protonated form at pH = 9 and showed 68% ± 1 adsorption in 30 min for EtOH_550. The FLX photocatalytic degradation under UV light irradiation was up to 17% higher than the photolytic degradation. The formation of hydroxyl radicals in the photocatalytic system (EtOH_550) was proven by the Coumarine probe assay, corroborating with the greater amount of α-[2-(methylamino)ethyl]benzylalcohol (MAEB), a by-product obtained after FLX oxidation. Additionally, the material achieved specific catalytic activity for the different organic compounds (RhB, MB, or FLX). Therefore, Nb2O5 nanofibers were efficient for degrading three different pollutants under UV light, proving a viable alternative for environmental remediation.
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Lu Y, Zhang X, Hou X, Feng M, Cao Z, Liu J. Functionalized 2D Nb 2C nanosheets for primary and recurrent cancer photothermal/immune-therapy in the NIR-II biowindow. NANOSCALE 2021; 13:17822-17836. [PMID: 34668898 DOI: 10.1039/d1nr05126a] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Near-infrared-II (NIR-II) cancer photothermal therapy (PTT) has become more and more attractive as the NIR-II light shows a higher tissue penetrating depth, which leads to better anti-cancer effects. Recently, the members of the MXene family have been reported as NIR-II photothermal agents, possessing a high specific surface area and a fascinating light-to-heat conversion rate at the same time. Herein, we reported a combination of NIR-II photothermal therapy and immune therapy based on the MXene family member niobium carbide (Nb2C). First, Nb2C nanosheets (NSs) under 50 nm were prepared. They showed a high photothermal conversion efficiency under a 1064-nm laser, and the NIR-II light showed a deeper tissue penetration depth. Then, a nanoplatform with high R837 stability and a high loading rate was obtained after modification with a polydopamine (PDA) layer on the surface of Nb2C. With the R837 modification, the percentage of mature dendritic cells (DCs) increased and the immune response enhanced, compared with the immune response caused by PTT only. Finally, a red blood cell (RBC) membrane was applied as a coat over the nanoplatform in order to avoid excessive blood clearance. During in vivo experiments, blood circulation of Nb2C@PDA-R837@RBC nanoparticles (NPs) was prolonged, and all primary tumors were eliminated. Secondary tumors were also inhibited effectively due to the strengthened immune response, proving that Nb2C@PDA-R837@RBC NPs could inhibit tumor recurrence. All the results above indicated Nb2C@PDA-R837@RBC NPs as a potential RBC camouflaged nanoplatform for the combination of effective PTT and immune therapy towards tumor treatment.
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Alias N, Hussain Z, Tan WK, Kawamura G, Muto H, Matsuda A, Lockman Z. Nanoporous anodic Nb 2O 5 with pore-in-pore structure formation and its application for the photoreduction of Cr(VI). CHEMOSPHERE 2021; 283:131231. [PMID: 34144283 DOI: 10.1016/j.chemosphere.2021.131231] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2021] [Revised: 06/08/2021] [Accepted: 06/12/2021] [Indexed: 06/12/2023]
Abstract
An anodic film with a nanoporous structure was formed by anodizing niobium at 60 V in fluorinated ethylene glycol (fluoride-EG). After 30 min of anodization, the anodic film exhibited a "pore-in-pore" structure; that is, there were smaller pores growing inside larger pores. The as-anodized film was weakly crystalline and became orthorhombic Nb2O5 after heat treatment. The energy band gap of the annealed nanoporous Nb2O5 film was 2.9 eV. A photocatalytic reduction experiment was performed on Cr(VI) under ultraviolet (UV) radiation by immersing the nanoporous Nb2O5 photocatalyst in a Cr(VI) solution at pH 2. The reduction process was observed to be very slow; hence, ethylenediaminetetraacetic acid (EDTA) was added as an organic hole scavenger, which resulted in 100% reduction after 45 min of irradiation. The photocatalytic reduction experiment was also performed under visible light, and findings showed that complete reduction achieved after 120 min of visible light exposure.
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Scharnberg ARDA, Berutti FA, Alves AK. Visible-light Bi-Fe-Nb-O photoanodes for solar-light driven hydrogen production. ENVIRONMENTAL TECHNOLOGY 2021; 42:4355-4362. [PMID: 32310020 DOI: 10.1080/09593330.2020.1758218] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2020] [Accepted: 04/14/2020] [Indexed: 06/11/2023]
Abstract
Currently, CO2 emission is the main cause of climate change and its various related environmental impacts. Therefore, we have as a prime the development of clean sources of energy. The hydrogen economy is very attractive in this regard, however, when generated from the methane reform, there are also large-scale CO2 emissions. Thus, this research aims to develop and characterize bismuth and iron niobate-based photoanodes for hydrogen production via water photoelectrolysis. Bi2FexNbO7 films were synthesized by the sol-gel method and deposited on FTO coated glass plates by dip-coating technique. The influence of heat treatment (400, 500 and 600°C) and amount of iron on the structure (Bi2FexNbO7, x = 0, 0.8, 1, 1.2) were evaluated. Optical, structural and morphological properties were performed, as well as photoanode efficiency in photocurrent assays. The results indicate that the increase of temperature as well as the amount of iron leads to a higher absorption capacity and hence to lower band gap values. Regarding the structural properties, it was possible to observe the BFNO phase in the samples treated at 500 and 600°C. The films heat-treated at 400°C had a heterogeneous texture and a good covering. At 600°C there were some cracks in films surface. Therefore, samples with more iron and treated at 400°C showed better responses in photocurrent assays. It can be concluded that bismuth-iron niobate has a great potential to be applied in photoelectrolysis hydrogen production.
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Chu K, Li X, Li Q, Guo Y, Zhang H. Synergistic Enhancement of Electrocatalytic Nitrogen Reduction Over Boron Nitride Quantum Dots Decorated Nb 2 CT x -MXene. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2021; 17:e2102363. [PMID: 34499407 DOI: 10.1002/smll.202102363] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 07/02/2021] [Indexed: 05/28/2023]
Abstract
Electrochemical N2 fixation represents a promising strategy toward sustainable NH3 synthesis, whereas the rational design of high-performance catalysts for the nitrogen reduction reaction (NRR) is urgently required but remains challenging. Herein, a novel hexagonal BN quantum dots (BNQDs) decorated Nb2 CTx -MXene (BNQDs@Nb2 CTx ) is explored as an efficient NRR catalyst. BNQDs@Nb2 CTx presents the optimum NRR activity with an NH3 yield rate of 66.3 µg h-1 mg-1 (-0.4 V) and a Faradaic efficiency of 16.7% (-0.3 V), outperforming most of the state-of-the-art NRR catalysts, together with an excellent stability. Theoretical calculations revealed that the synergistic interplay of BNQDs and Nb2 CTx enabled the creation of unique interfacial B sites serving as NRR catalytic centers capable of enhancing the N2 activation, lowering the reaction energy barrier and impeding the H2 evolution.
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Ali RF, Guo I, Kang H, Radford MJ, Yapp DT, Gates BD. Tuning the Surface Chemistry of Second-Harmonic-Active Lithium Niobate Nanoprobes Using a Silanol-Alcohol Condensation Reaction. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2021; 37:7689-7700. [PMID: 34128677 DOI: 10.1021/acs.langmuir.1c00645] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The surface functionalization of nanoparticles (NPs) is of great interest for improving the use of NPs in, for example, therapeutic and diagnostic applications. The conjugation of specific molecules with NPs through the formation of covalent linkages is often sought to provide a high degree of colloidal stability and biocompatibility, as well as to provide functional groups for further surface modification. NPs of lithium niobate (LiNbO3) have been explored for use in second-harmonic-generation (SHG)-based bioimaging, expanding the applications of SHG-based microscopy techniques. The efficient use of SHG-active LiNbO3 NPs as probes will, however, require the functionalization of their surfaces with molecular reagents such as polyethylene glycol and fluorescent molecules to enhance their colloidal and chemical stability and to enable a correlative imaging platform. Herein, we demonstrate the surface functionalization of LiNbO3 NPs through the covalent attachment of alcohol-based reagents through a silanol-alcohol condensation reaction. Alcohol-based reagents are widely available and can have a range of terminal functional groups such as carboxylic acids, amines, and aldehydes. Attaching these molecules to NPs through the silanol-alcohol condensation reaction could diversify the reagents available to modify NPs, but this reaction pathway must first be established as a viable route to modifying NPs. This study focuses on the attachment of a linear alcohol functionalized with carboxylic acid and its use as a reactive group to further tune the surface chemistry of LiNbO3 NPs. These carboxylic acid groups were reacted to covalently attach other molecules to the NPs using copper-free click chemistry. This derivatization of the NPs provided a means to covalently attach polyethylene glycols and fluorescent probes to the NPs, reducing NP aggregation and enabling multimodal tracking of SHG nanoprobes, respectively. This extension of the silanol-alcohol condensation reaction to functionalize the surfaces of LiNbO3 NPs can be extended to other types of nanoprobes for use in bioimaging, biosensing, and photodynamic therapies.
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Khan SU, Hussain S, Perini JAL, Khan H, Khan S, Zanoni MVB. Self-doping of Nb 2O 5NC by cathodic polarization for enhanced conductivity properties and photoelectrocatalytic performance. CHEMOSPHERE 2021; 272:129880. [PMID: 33601209 DOI: 10.1016/j.chemosphere.2021.129880] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 01/06/2021] [Accepted: 02/03/2021] [Indexed: 06/12/2023]
Abstract
A simple novel electrochemical reduction approach was developed for the self-doping of Nb4+ in niobium oxide nanochannels (Nb2O5NC), changing the conductivity, optical properties, and photocatalytic properties of the material. Nb2O5NC was synthesized using different electrolytes: 0.4 wt% HF in 1 M H2SO4 (EI), 0.4 M NH4F in glycerol (EII), and 0.25 g NH4F with 4 vol% water in glycol at 50 °C (EIII). Field emission scanning electron microscopy (FEG-SEM) analysis showed well-organized arrays of Nb2O5 nanochannels produced on Nb foil, with varying tube diameters in the order EII < EI < EIII and film thickness in the order EI < EII < EIII, which drastically affected the photocurrent vs. potential curves. In order to self-dope the Nb2O5, the samples were electrochemically reduced in 0.1 M KH2PO4 buffer solution (pH 10) for 5 min, at -2.5 V vs. Ag/AgCl, resulting in the doped samples denoted P-EI, P-EII, and P-EIII. The results showed that reduction of Nb5+ to Nb4+ occurred for all the Nb2O5NC samples, leading to decreased surface charge transfer resistance between the Nb2O5NC and the electrolyte, as well as increases of the charge carrier density and photocurrent for all the self-doped samples, compared to undoped samples. Sample P-EI was also tested for the degradation of reactive red 120 (RR120) dye, achieving efficient photoelectrocatalytic degradation of a 10 mg L-1 dye solution. These results reveal that the self-doping approach can enhance the photoelectrocatalytic properties of Nb2O5 photoanode, offering an alternative way for the removal of reactive dyes.
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Domingues FS, Geraldino HCL, Freitas TKFDS, de Almeida CA, Figueiredo FFD, Garcia JC. Photocatalytic degradation of real textile wastewater using carbon black-Nb 2O 5 composite catalyst under UV/Vis irradiation. ENVIRONMENTAL TECHNOLOGY 2021; 42:2335-2349. [PMID: 31852357 DOI: 10.1080/09593330.2019.1701565] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2019] [Accepted: 12/02/2019] [Indexed: 06/10/2023]
Abstract
This work investigated the impregnation of Nb2O5 into carbon black (CB) in different ratios and its effect in photocatalytic degradation of real wastewater from a dyeing factory by advanced oxidative processes (AOP). Synthesized catalysts were characterized regarding their crystalline structure (DRX, micro-Raman), morphology (MEV), textural (BET area) and optical properties (bandgap energy by diffuse reflectance) and pH at the point of zero charge (pHpzc). Preliminary tests showed better photodegradation results in the acidic medium after 5 h of irradiation with NCB-0.5 (Nb2O5:CB 0.5:1). Treatment parameters optimization was carried out using response surface methodology based on Box-Behnken experimental design. Catalyst concentration, solution pH and irradiation time were varied, analysing absorbance reduction (285 and 574 nm), COD and TOC removal after treatment as responses. The composite catalyst showed improved photocatalytic activity, attributed to an increase in adsorption capacity and the bandgap narrowing, redshifting the absorption edge wavelength to the visible region, brought by CB impregnation. Optimal conditions were found at 0.250 g L-1 of catalyst, pH 2.0 and 5 h of irradiation, removing 72.19% and 93.52% of absorbance in 285 and 574 nm, respectively, 51.29% of COD and 70.70% of TOC using NCB-0.5.
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Paris EC, Malafatti JOD, Sciena CR, Junior LFN, Zenatti A, Escote MT, Moreira AJ, Freschi GPG. Nb 2O 5 nanoparticles decorated with magnetic ferrites for wastewater photocatalytic remediation. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:23731-23741. [PMID: 33097995 DOI: 10.1007/s11356-020-11262-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 10/13/2020] [Indexed: 06/11/2023]
Abstract
Nanotechnology has been studied on environmental remediation processes to foster greater photocatalysts efficiency and reuse in wastewater. This study investigated the photocatalytic efficiency and viability of niobium pentoxide (Nb2O5) nanoparticles decorated with magnetic ferrite (cobalt ferrite (CoFe2O4) or magnesium ferrite (MgFe2O4)) for atrazine photodegradation. Thus, the decorated Nb2O5 was synthesized by the polymeric precursor method, forming nanoparticles with sizes ranging from 25 to 50 nm. Nanocomposite elementary analyses showed a homogeneous distribution of elements on all particles surface. Efficient magnetic saturation was observed for pure CoFe2O4 (53 emu g-1) and MgFe2O4 (19 emu g-1) nanoparticles, promoting the magnetic removal of Nb2O5:CoFe2O4 and Nb2O5:MgFe2O4 nanocomposites. Photocatalytic assays showed 88% efficiency for atrazine photodegradation with all nanomaterials, which represented a 21% increase compared to photolysis in the 1st cycle. The magnetic nanocomposites when applied to a 5th cycle maintained the atrazine photodegradation activity. In this way, magnetic Nb2O5-based nanocomposites decorated with ferrite nanoparticles showed an efficient photocatalytic response, in addition to posterior magnetic removal from the aqueous medium. Therefore, the evaluated magnetic Nb2O5 nanocomposites may be an alternative to enhance the wastewater removal process and foster the reuse in advanced oxidative processes.
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David GF, Pereira SDPS, Fernandes SA, Cubides-Roman DC, Siqueira RK, Perez VH, Lacerda V. Fast pyrolysis as a tool for obtaining levoglucosan after pretreatment of biomass with niobium catalysts. WASTE MANAGEMENT (NEW YORK, N.Y.) 2021; 126:274-282. [PMID: 33784571 DOI: 10.1016/j.wasman.2021.03.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 03/01/2021] [Accepted: 03/15/2021] [Indexed: 06/12/2023]
Abstract
Levoglucosan (LGA) is a promising chemical platform derived from the pyrolysis of biomass that offers access to a variety of value-added products. We report an efficient route to produce LGA via the pretreatment of biomass with niobium compounds (oxalate, chloride and oxide) followed by fast pyrolysis coupled with gas chromatography-mass spectrometry (Py-GC-MS) at temperatures of 350-600 °C. Catalytic pretreatment reduces the quantity of lignin in the biomass, concentrates the cellulose and enhance LGA formation during fast pyrolysis. The pretreatment also removes alkaline metals, preventing competitive side reactions. The effect of several parameters such as catalyst weight, time, temperature, and solvent, with the optimal pretreatment conditions determined to be 3 (wt.%) niobium oxalate for 1 h at 23 °C in water. Pretreatment increased the LGA yields by 6.40-fold for sugarcane bagasse, 4.15-fold for elephant grass, 4.13-fold for rice husk, 2.86-fold for coffee husk, and 1.86-fold for coconut husk as compared to the raw biomasses. These results indicate that biomass pretreatment using niobium derivates prior fast pyrolysis can be a promising technique for biomass thermochemical conversion in LGA and others important pyrolytic products.
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Cui C, Guo R, Ren E, Xiao H, Lai X, Qin Q, Jiang S, Shen H, Zhou M, Qin W. Facile hydrothermal synthesis of rod-like Nb 2O 5/Nb 2CT x composites for visible-light driven photocatalytic degradation of organic pollutants. ENVIRONMENTAL RESEARCH 2021; 193:110587. [PMID: 33307080 DOI: 10.1016/j.envres.2020.110587] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 10/30/2020] [Accepted: 12/02/2020] [Indexed: 06/12/2023]
Abstract
The MXene-based transition metal oxide composite is a potential candidate for photocatalysts. Rod-like pseudohexagonal phase Nb2O5/Nb2CTx composites were synthesized by a simple hydrothermal oxidation of 2D layered Nb2CTx. The Nb2O5/Nb2CTx composites show superior photocatalytic activity for 98.5% of degradation of Rhodamine B (RhB) for 120 min and 91.2% of tetracycline hydrochloride (TC-HCl) for 180 min under visible light irradiation. The Schottky junction is formed between Nb2O5 nanorods and Nb2CTx and the photo-generated carriers are effectively separated, enhancing the photocatalytic activity of the Nb2O5/Nb2CTx. High photoactivity and cycle stability of Nb2O5/Nb2CTx composites indicate that hydrothermal oxidation of 2D layered Nb2CTx is an alternative to prepare efficient photocatalyst for degradation of organic pollutants.
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Yang C, Luo Y, Lin H, Ge M, Shi J, Zhang X. Niobium Carbide MXene Augmented Medical Implant Elicits Bacterial Infection Elimination and Tissue Regeneration. ACS NANO 2021; 15:1086-1099. [PMID: 33372766 DOI: 10.1021/acsnano.0c08045] [Citation(s) in RCA: 93] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Incurable bacterial infections, impenetrable microbial biofilm, and irreversible antibiotic resistance are among the most dangerous threats for humans. With few effective strategies available in antimicrobial and antibiofilm development, innovative methodologies inspired by the advances in other fields such as nanomedicine are becoming more and more attractive to realize innovative antibacterial agents. Herein, a 2D niobium carbide (Nb2C) MXene titanium plate (Nb2C@TP)-based clinical implant with practical multimodal anti-infection functions was developed. Such emerging modes are capable of destroying biofilms for direct bacteria elimination through down-regulating bacterial energy metabolism pathways, suppressing biofilm formation, and enhancing as-formed biofilm detachment via an activating accessory gene regulator. Another intriguing feature of this nanomedicine is the sensitization ability toward bacteria via photothermal transduction, which reduces the temperature necessary for bacteria eradication and mitigates possible normal tissue damage. Moreover, the Nb2C@TP medical implant is able to alleviate proinflammatory responses by scavenging excessive reactive oxygen species in infectious microenvironments, benefiting angiogenesis and tissue remodeling.
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D'Ambrosi R, Nuara A, Mariani I, Di Feo F, Ursino N, Hirschmann M. Titanium Niobium Nitride Mobile-Bearing Unicompartmental Knee Arthroplasty Results in Good to Excellent Clinical and Radiographic Outcomes in Metal Allergy Patients With Medial Knee Osteoarthritis. J Arthroplasty 2021; 36:140-147.e2. [PMID: 32773267 DOI: 10.1016/j.arth.2020.07.028] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/05/2020] [Accepted: 07/11/2020] [Indexed: 02/02/2023] Open
Abstract
BACKGROUND The main purpose of the present study was to analyze the clinical and radiological outcomes of patients with positive skin patch tests who underwent medial mobile-bearing titanium niobium nitride unicompartmental knee arthroplasty (UKA) during a mid-term follow-up. METHODS Thirty-seven patients with positive skin patch tests were included in this prospective study. The clinical evaluation consisted of Oxford Knee Score and Knee Society Score (KSS) reports. Each patient was clinically evaluated the day before surgery (T0) as well as at T1 (11.9 ± 1.3 months) and during the final follow-up T2 (67.2 ± 19.1 months). The positioning of the UKA was evaluated during the final follow-up using standardized radiographs (T2: 67.2 ± 19.1 months). RESULTS Oxford and KSS ranged from a respective mean preoperative value of 23.0 ± 2.7 and 51.5 ± 5.0 to 42.1 ± 1.7 and 87.6 ± 2.2, respectively, at T1 (P < .001) and to the final values of 45.0 ± 1.9 and 91.9 ± 3.4, respectively, at T2 (P < .001 both vs T1 and T2). At T2, the mean femoral angle was 7.0° ± 4.5°, mean tibial angle was 3.0° ± 2.1°, and mean tibial slope was 5.1° ± 3.2°. A significant difference was found between KSS and Oxford with ANOVA for repeated measures over time (P < .001). The Oxford and KSS scores showed significant improvements during each follow-up. No complications were found, and not a single patient required a revision surgery during the follow-up period. CONCLUSION The hypoallergenic titanium niobium nitride mobile-bearing UKA showed comparable results to standard CoCr UKA regardless of the gender, age, BMI, and implant size of metal allergy patients with medial knee osteoarthritis. Careful patient selection processes and accurate medical histories played key roles in the choice of hypersensitivity-friendly implants.
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Herbster M, Döring J, Nohava J, Lohmann CH, Halle T, Bertrand J. Retrieval study of commercially available knee implant coatings TiN, TiNbN and ZrN on TiAl6V4 and CoCr28Mo6. J Mech Behav Biomed Mater 2020; 112:104034. [PMID: 32871541 DOI: 10.1016/j.jmbbm.2020.104034] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 07/21/2020] [Accepted: 08/10/2020] [Indexed: 12/13/2022]
Abstract
BACKGROUND Coated implant components for total knee arthroplasties are primarily used for metal-sensitive patients and are offered by different manufacturers. However, there is only little knowledge with respect to their coating design and supposed superior tribological performance. Our aim was to compare retrieved coated implants by identifying present damages, critical factors influencing the coating durability and their correlation to the clinical performance. MATERIALS AND METHODS 28 retrieved knee endoprostheses from nine different manufacturers were analyzed for potential surface defects as well as the coating strategy for each manufacturer. The coating designs were investigated on preserved regions with regard to substrate and coating material, layer thickness and roughness using scanning electron microscopy and confocal microscopy. Furthermore, the mechanical properties and adhesive strength of the layer were evaluated by nanoindentation and scratch testing. The friction performance of the coatings against ultra-high molecular weight polyethylene (UHMWPE) was investigated in a tribological test. In addition, clinical data were collected and evaluated for all patients. RESULTS Our cohort of 28 retrieved knee endoprostheses exhibited different damage patterns in the articulating area with an incidence of 79% for discoloration and 21% for coating delamination. All coatings presented droplets, macropores and pinholes in preserved areas, which can be attributed to the coating and post-polishing processes. Interestingly, the adhesive strength was significantly increased by 60.4% for titanium nitride coatings on TiAl6V4 alloy in comparison to CoCr28Mo6 substrates. The friction behavior of titanium nitride coatings against UHMWPE is similar to uncoated CoCr28Mo6 alloy and lowest for the ZrN multi-layer coating with a reduction of 14%. DISCUSSION This study shows that manufacturing related coating deposition defects can cause wear due to adhesive failure and corrosion underneath the coating layers. Adhesive strength was identified as a critical factor for coating durability. Minor adhesive strength was present on CoCr28Mo6 cast alloy in comparison to good adhesion of Ti-based coatings on TiAl6V4 wrought alloy. Based on our findings, this is consistent to higher prevalence rates of CoCr28Mo6/TiNbN coatings for gross delamination and pitting damage with increasing implantation time.
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Shani L, Michelson AN, Minevich B, Fleger Y, Stern M, Shaulov A, Yeshurun Y, Gang O. DNA-assembled superconducting 3D nanoscale architectures. Nat Commun 2020; 11:5697. [PMID: 33173061 PMCID: PMC7656258 DOI: 10.1038/s41467-020-19439-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 10/01/2020] [Indexed: 12/13/2022] Open
Abstract
Studies of nanoscale superconducting structures have revealed various physical phenomena and led to the development of a wide range of applications. Most of these studies concentrated on one- and two-dimensional structures due to the lack of approaches for creation of fully engineered three-dimensional (3D) nanostructures. Here, we present a 'bottom-up' method to create 3D superconducting nanostructures with prescribed multiscale organization using DNA-based self-assembly methods. We assemble 3D DNA superlattices from octahedral DNA frames with incorporated nanoparticles, through connecting frames at their vertices, which result in cubic superlattices with a 48 nm unit cell. The superconductive superlattice is formed by converting a DNA superlattice first into highly-structured 3D silica scaffold, to turn it from a soft and liquid-environment dependent macromolecular construction into a solid structure, following by its coating with superconducting niobium (Nb). Through low-temperature electrical characterization we demonstrate that this process creates 3D arrays of Josephson junctions. This approach may be utilized in development of a variety of applications such as 3D Superconducting Quantum interference Devices (SQUIDs) for measurement of the magnetic field vector, highly sensitive Superconducting Quantum Interference Filters (SQIFs), and parametric amplifiers for quantum information systems.
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