42 results on '"Zhang, Wenfeng"'
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2. Application and analysis of superconducting magnetic eddy current heater used in wind thermal power generation system.
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Zhang, Wenfeng, Chen, Chen, Liu, Zeyuan, Wang, Youhua, and Liu, Chengcheng
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WIND power , *HEAT storage devices , *SUPERCONDUCTORS , *SUPERCONDUCTING coils , *HEATING , *WIND forecasting - Abstract
In order to cope with the grid fluctuation caused by large‐scale wind power connected to the grid, the wind thermal power generation system has been proposed and extensively studied. The wind thermal power generation system uses a wind turbine to drive a heat generation device to heat the heat storage medium, which is further exchanged to drive a turbine to generate electricity. A superconducting magnetic eddy current heater (SMH) is proposed for the characteristics of wind thermal power generation system, which uses non‐resistive, large current‐carrying superconducting coils for excitation, and has high output efficiency and power density. The working principle of magnetic eddy current heating is analysed, and the structure of SMH with no ferromagnetic material and two heating screens inside and outside is proposed according to the characteristics of SMH. An analytical model of the SMH is established, and the influence of the structure and materials of the SMH on the magnetic field distribution is analysed. Based on this, a 22‐pole SMH was designed and analysed for output power at 10–20 rpm. A three‐dimensional magnetism‐stress combined analysis model of SMH is established, and the strain and stress characteristics of SMH are simulated under the condition of maximum output power, which verifies the feasibility of the mechanical properties of existing superconducting materials for application in SMH. [ABSTRACT FROM AUTHOR]
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- 2024
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3. A dual‐mode integration framework and application to agile feedback design of launch vehicles.
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Zhang, Wenfeng, Cai, Xiaoshuang, Liu, Zhendong, Luo, Shan, and Yu, Rendong
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- 2024
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4. Surface Passivation of Perovskite by Hole‐Blocking Layer toward Efficient and Stable Inverted Solar Cells.
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Wang, Yandong, Zhao, Rongmei, Yu, Xin, Li, Liufei, Lin, Puan, Zhang, Shantao, Gao, Shuang, Li, Xinyu, Zhang, Wenfeng, Zhang, Wen‐Hua, and Yang, Shangfeng
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SURFACE passivation ,PASSIVATION ,SOLAR cells ,FRONTIER orbitals ,PHOTOVOLTAIC power systems ,PEROVSKITE ,ELECTRON transport - Abstract
Inverted (p‐i‐n) perovskite solar cells (PSCs) are advantageous in terms of easy fabrication, low‐temperature processibility, negligible hysteresis, and excellent compatibility with the tandem devices in comparison with the regular (n‐i‐p) counterparts. Hole‐blocking layer is crucial for efficient electron transport of inverted PSCs, and only a single hole‐blocking layer of bathocuproine (BCP) is used typically. Herein, bis[2‐(diphenylphosphino)phenyl] ether oxide (DPEPO) with a deep highest occupied molecular orbital (HOMO) energy level is incorporated atop of perovskite film as an auxiliary hole‐blocking layer, resulting in an enhanced electron transport of inverted PSC devices. The P=O group within DPEPO can coordinate with Pb2+ cations of perovskite, leading to passivation of surface defects of perovskite. Besides, incorporation of DPEPO hole‐blocking layer prohibits undesired hole transport from perovskite to PCBM electron transport layer (ETL), thus suppressing non‐radiative electron–hole recombination. As a result, combined with BCP hole‐blocking layer, inverted PSC devices based on double hole‐blocking layers exhibit a decent power conversion efficiency (PCE) of 24.17% with a high open‐circuit voltage (Voc) of 1.15 V which dramatically surpasses that based on single hole‐blocking layer (22.26%). Moreover, incorporation of hydrophobic DPEPO helps to improve the ambient and thermal stabilities of inverted PSC devices. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Benzothieno[3,2‐b]thiophene‐Based Noncovalent Conformational Lock Achieves Perovskite Solar Cells with Efficiency over 24 %.
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Zhang, Heng, Yu, Xin, Li, Mengjia, Zhang, Zuolin, Song, Zonglong, Zong, Xueping, Duan, Gongtao, Zhang, Wenfeng, Chen, Cong, Zhang, Wen‐Hua, Liu, Yongsheng, and Liang, Mao
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SOLAR cell efficiency ,PEROVSKITE ,THIOPHENES ,SOLAR cells ,SURFACE passivation ,ORGANIC semiconductors - Abstract
Organic semiconductors with noncovalently conformational locks (OSNCs) are promising building blocks for hole‐transporting materials (HTMs). However, lack of satisfied neighboring building blocks negatively impacts the optoelectronic properties of OSNCs‐based HTMs and imperils the stability of perovskite solar cells (PSCs). To address this limitation, we introduce the benzothieno[3,2‐b]thiophene (BTT) to construct a new OSNC, and the resulting HTM ZS13 shows improved intermolecular charge extraction/transport properties, proper energy level, efficient surface passivation effect. Consequently, the champion devices based on doped ZS13 yield an efficiency of 24.39 % and 20.95 % for aperture areas of 0.1 and 1.01 cm2, respectively. Furthermore, ZS13 shows good thermal stability and the capability of inhibiting I− ion migration, thus, leading to enhanced device stability. The success in neighboring‐group engineering can triggered a strong interest in developing thienoacene‐based OSNCs toward efficient and stable PSCs. [ABSTRACT FROM AUTHOR]
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- 2023
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6. Fullerene modification of WO3 electron transport layer toward high‐efficiency MA‐free perovskite solar cells with eliminated light‐soaking effect.
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Yu, Xin, Cai, Bing, Zhang, Jinxia, Li, Xingcheng, Wang, Xue, Duan, Gongtao, Zhang, Wenfeng, Liu, Xinhang, Zhang, Wen‐Hua, and Yang, Shangfeng
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- 2023
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7. Production and characterization of monoclonal antibodies against mandarinfish ranavirus and first identification of pyloric caecum as the major target tissue.
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Zhang, Wenfeng, Deng, Hengwei, Fu, Yuting, Fu, Weixuan, Weng, Shaoping, He, Jianguo, and Dong, Chuanfu
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MONOCLONAL antibodies , *CECUM , *VIRAL proteins , *CYTOSKELETAL proteins , *TISSUES , *CELLULAR inclusions - Abstract
Mandarinfish ranavirus (MRV), also known as a variant of largemouth bass virus (LMBV), is an emerging pathogen in mandarinfish aquaculture. In this study, monoclonal antibodies (mAbs) against MRV were produced and characterized, and 7 mAbs were obtained through Western blotting screening and all 7 mAbs specifically recognized MRV/LMBV but not several piscine iridoviruses as ISKNV, GIV and TFV. By LC MS/MS analysis, the recognized viral proteins by seven mAbs were identified as MRV‐pORF47L, MRV‐pORF55R, MRV‐pORF57L, MRV‐pORF77L and MRV‐pORF78L, respectively, and all five viral proteins are late expression structural proteins by Western blotting. Based on mAb 1C4, immuno‐histochemistry and immuno‐histo‐fluorescence were performed to re‐assess the tissue tropism of MRV. The result showed that abundant reactive signals were observed in infected spleen, kidney as well as intestine and pyloric caecum. Real‐time quantitative PCR also demonstrated that spleen as well as pyloric caecum and intestines are the major target tissue upon MRV infection. In infected intestines and pyloric caecum, numerous enlarged, multinucleated cells with intracytoplasmic inclusions were identified as the target cells of MRV, suggesting that MRV serves as a digestive tract pathogen to mandarinfish, which may explain why acute infection of MRV can cause the typical clinicopathology featured by severe ascites. [ABSTRACT FROM AUTHOR]
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- 2023
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8. MATE transporter GFD1 cooperates with sugar transporters, mediates carbohydrate partitioning and controls grain‐filling duration, grain size and number in rice.
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Sun, Changhui, Wang, Yang, Yang, Xiaorong, Tang, Lu, Wan, Chunmei, Liu, Jiqing, Chen, Congping, Zhang, Hongshan, He, Changcai, Liu, Chuanqiang, Wang, Qian, Zhang, Kuan, Zhang, Wenfeng, Yang, Bin, Li, Shuangcheng, Zhu, Jun, Sun, Yongjian, Li, Weitao, Zhou, Yihua, and Wang, Pingrong
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GRAIN size ,CARBOHYDRATES ,GRAIN ,RICE hulls ,GOLGI apparatus ,RICE ,SUGAR - Abstract
Summary: More than half of the world's food is provided by cereals, as humans obtain >60% of daily calories from grains. Producing more carbohydrates is always the final target of crop cultivation. The carbohydrate partitioning pathway directly affects grain yield, but the molecular mechanisms and biological functions are poorly understood, including rice (Oryza sativa L.), one of the most important food sources. Here, we reported a prolonged grain filling duration mutant 1 (gfd1), exhibiting a long grain‐filling duration, less grain number per panicle and bigger grain size without changing grain weight. Map‐based cloning and molecular biological analyses revealed that GFD1 encoded a MATE transporter and expressed high in vascular tissues of the stem, spikelet hulls and rachilla, but low in the leaf, controlling carbohydrate partitioning in the stem and grain but not in the leaf. GFD1 protein was partially localized on the plasma membrane and in the Golgi apparatus, and was finally verified to interact with two sugar transporters, OsSWEET4 and OsSUT2. Genetic analyses showed that GFD1 might control grain‐filling duration through OsSWEET4, adjust grain size with OsSUT2 and synergistically modulate grain number per panicle with both OsSUT2 and OsSWEET4. Together, our work proved that the three transporters, which are all initially classified in the major facilitator superfamily family, could control starch storage in both the primary sink (grain) and temporary sink (stem), and affect carbohydrate partitioning in the whole plant through physical interaction, giving a new vision of sugar transporter interactome and providing a tool for rice yield improvement. [ABSTRACT FROM AUTHOR]
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- 2023
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9. Digital Twin Enables Rational Design of Ultrahigh‐Power Lithium‐Ion Batteries.
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Zhang, Huimin, Ren, Dongsheng, Ming, Hai, Zhang, Wenfeng, Cao, Gaoping, Liu, Jianhong, Wang, Li, Song, Junliang, Qiu, Jingyi, Wang, Jingliang, He, Xiangming, and Zhang, Hao
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DIGITAL twins ,LITHIUM-ion batteries ,ELECTRIC power distribution grids ,ELECTRIC batteries ,ENERGY density ,ELECTRIC vehicles ,LITHIUM cells - Abstract
With the widespread applications of electric vehicles, power grid stabilization, and high‐pulsed power loads, high‐power lithium‐ion batteries (LIBs) are in urgent demand. However, the existing experimental‐based design of high‐power batteries is usually costly and inefficient, and provides limited information on the complex physicochemical processes inside the batteries. Digital twin concept is promising for capturing the batteries' electrochemical performance, and optimizing the power capability of LIBs. Here, an electrochemical‐thermal coupled model is developed as a digital twin model for rational design of ultrahigh‐power LiFePO4/graphite LIBs. The model can accurately predict the batteries' performance and help to predetermine the optimal parameters to achieve an ultrahigh power capability. After model‐guided optimization, the battery shows a high energy density of 92.38 Wh kg−1 at an ultrafast discharging current of 50 C and can withstand 150 C pulse discharging tests. Notably, the digital twin model can reveal experimentally inaccessible time‐ and space‐resolved information and identify the rate‐determining steps inside the battery. Hence, model‐driven optimization of ultrahigh‐power LiFePO4/graphite batteries is successfully realized aiming at the critical factors in the rate‐determining steps. The work provides an instructive design of ultrahigh‐power LiFePO4/graphite batteries, which might guide the future direction to boost the power capability of LIBs. [ABSTRACT FROM AUTHOR]
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- 2023
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10. Two‐Dimensional Van Der Waals Topological Materials: Preparation, Properties, and Device Applications.
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Zhang, Gaojie, Wu, Hao, Zhang, Liang, Yang, Li, Xie, Yuanmiao, Guo, Fei, Li, Hongda, Tao, Boran, Wang, Guofu, Zhang, Wenfeng, and Chang, Haixin
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- 2022
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11. Strategy of Enhancing Built‐in Field to Promote the Application of C‐TiO2/SnO2 Bilayer Electron Transport Layer in High‐Efficiency Perovskite Solar Cells (24.3%).
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Shu, Hui, Peng, Changtao, Chen, Qian, Huang, Zhangfeng, Deng, Chen, Luo, Wenjie, Li, Haijin, Zhang, Wenfeng, Zhang, Wenhua, and Huang, Yuelong
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- 2022
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12. Changes in the TCR repertoire of T‐cell subsets during culture of cytokine‐induced killer cells.
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Liang, Guozheng, Feng, Gang, Chen, Hui, Li, Ling, Hu, Jicong, Zhou, Chuandong, Li, Jiawen, Shen, Han, Wu, Fenglin, Tao, Changli, Liu, Yan, Zhang, Wenfeng, and Shao, Hongwei
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MAJOR histocompatibility complex ,ANTIGEN receptors ,CELL culture ,T cell receptors - Abstract
Cytokine‐induced killer (CIK) cells are a group of highly heterogeneous T cells expressing diverse T‐cell antigen receptors (TCRs), but possessing wide major histocompatibility complex (MHC)‐unrestricted antitumour activity, which have been used in the treatment of many tumours. However, the clonal diversity of different T‐cell subsets and whether there is a certain clonal preference during CIK culture remains to be clarified. We found that the proportion of oligoclones seen in some subfamilies of freshly isolated T cells decreased in varying degrees after culturing. This indicates that the diversity of T‐cell clones had been restored to a certain extent. The diversity differed among different T‐cell subsets, as some TCR subfamily oligoclones mainly appeared in CD3+CD56+ cells, which also indicates the heterogeneity of the CIK cell composition. [ABSTRACT FROM AUTHOR]
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- 2022
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13. Molecular‐Scale Hydrophobic Modification of Ni‐Rich Cathode Materials Toward Superior Critical Endurability and Environmental Stability.
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Mu, Yue, Ming, Hai, Chen, Xuefang, Zhang, Wenfeng, Cao, Gaoping, Xiang, Yu, and Qiu, Jingyi
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CATHODES ,SURFACE passivation ,LITHIUM compounds ,EXTREME environments ,CARBON dioxide ,LITHIUM-ion batteries - Abstract
Ni‐rich layered oxides have been considered one of the most promising cathode materials for lithium‐ion batteries on account of their high reversible capacity. However, their chemical sensitivity to moisture and carbon dioxide results in the formation and growth of residual lithium compounds, leading to a deterioration in electrochemical performance and difficulty in cathode electrode preparation. In this work, a passivation coating of polydimethylsiloxane with 5 molecular layers is successfully coated on LiNi0.8Co0.1Mn0.1O2 particles. To examine the hydrophobicity of polydimethylsiloxane, bare and coated NCM811 are exposed to a hot and humid chamber for dozens of hours, even exposure to damp air over 120 h. The results indicate that the hydrophobic coating can inhibit the formation and growth of residual lithium compounds on the surface of LiNi0.8Co0.1Mn0.1O2, resulting in slightly less degradation in electrochemical performance. Herein, a rapid, low‐cost, and easily employed method to generate an even hydrophobic/passivation surface is developed, which provides a generic approach to treat various electrode materials, especially nanosized and water‐sensitive ones, to improve their tolerance to extreme environments. [ABSTRACT FROM AUTHOR]
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- 2022
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14. High‐Performance and Low‐Power Polycrystalline MoTe2 Thin Film Transistors with Solution‐Processed Ternary Oxide High‐k Dielectric.
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Liu, Yuan, Wen, Xiaokun, Lei, Wenyu, Yang, Li, Zhang, Pengzhen, Zhang, Yuhui, Chang, Haixin, and Zhang, Wenfeng
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THIN film transistors ,METAL oxide semiconductor field-effect transistors ,DIELECTRICS ,TRANSITION metals ,THRESHOLD voltage - Abstract
Besides the widely investigated potential as alternative to silicon in microelectronics, semiconducting 2D transition metal dichalcogenides (TMDs) also show appealing prospects in thin film transistors (TFTs)‐based applications, while still suffer from insufficient demonstration. Herein, the authors systematically report high‐performance and low‐power chemical vapor deposition‐grown polycrystalline molybdenum ditelluride (MoTe2) TFTs with solution‐processed ternary Hf0.5Zr0.5O2/HfAlO2 high‐k dielectric. Benefitting from the optimized high quality HfAlO2 film synthesis and proper postannealing treatment, the constructed MoTe2 TFTs exhibit a high mobility ≈27.24 cm2 V−1 S−1, a current on/off ratio ≈6.43 × 105, threshold voltage ≈−3.27 V, and subthreshold swing (SS) value ≈152.4 mV dec−1, respectively. Moreover, by supplementing another solution‐processed layer of ferroelectric Hf0.5Zr0.5O2 to form double layer of HfAlO2/Hf0.5Zr0.5O2 dielectric, the device performance can be further improved with an ignorable hysteresis, increased mobility of ≈55.53 cm2 V−1 S−1, and significantly reduced SS value of ≈110.16 mV dec−1, respectively. The current investigation offers a feasible strategy to fabricate high‐performance and low‐power MoTe2 TFTs for potential TMDs‐based TFTs applications. [ABSTRACT FROM AUTHOR]
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- 2022
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15. Highly‐Tunable Intrinsic Room‐Temperature Ferromagnetism in 2D van der Waals Semiconductor CrxGa1−xTe.
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Zhang, Gaojie, Wu, Hao, Zhang, Liang, Zhang, Shanfei, Yang, Li, Gao, Pengfei, Wen, Xiaokun, Jin, Wen, Guo, Fei, Xie, Yuanmiao, Li, Hongda, Tao, Boran, Zhang, Wenfeng, and Chang, Haixin
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FERROMAGNETISM ,SEMICONDUCTORS ,QUANTUM confinement effects ,CURIE temperature ,MAGNETIC moments - Abstract
The combination of semiconductivity and tunable ferromagnetism is pivotal for electrical control of ferromagnetism and next‐generation low‐power spintronic devices. However, Curie temperatures (TC) for most traditional intrinsic ferromagnetic semiconductors (≤200 K) and recently discovered two‐dimensional (2D) ones (<70 K) are far below room temperature. 2D van der Waals (vdW) semiconductors with intrinsic room‐temperature ferromagnetism remain elusive considering the unfavored 2D long‐range ferromagnetic order indicated by Mermin–Wagner theorem. Here, vdW semiconductor CrxGa1−xTe crystals exhibiting highly tunable above‐room‐temperature ferromagnetism with bandgap 1.62–1.66 eV are reported. The saturation magnetic moment (Msat) of CrxGa1−xTe crystals can be effectively regulated up to ≈5.4 times by tuning Cr content and ≈75.9 times by changing the thickness. vdW CrxGa1−xTe ultrathin semiconductor crystals show robust room‐temperature ferromagnetism with the 2D quantum confinement effect, enabling TC 314.9–329 K for nanosheets, record‐high for intrinsic vdW 2D ferromagnetic semiconductors. This work opens an avenue to room‐temperature 2D vdW ferromagnetic semiconductor for 2D electronic and spintronic devices. [ABSTRACT FROM AUTHOR]
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- 2022
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16. Fiber modifications enable fowl adenovirus 4 vectors to transduce human cells.
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Zhang, Wenfeng, Guo, Xiaojuan, Yin, Fengcai, Zou, Xiaohui, Hou, Wenzhe, and Lu, Zhuozhuang
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Background: Pre‐existing immunities hamper the application of human adenovirus (HAdV) vectors in gene therapy or vaccine development. Fowl adenovirus (FAdV)‐based vector might represent an alternative. Methods: An intermediate plasmid containing FAdV‐4 fiber genes, pMD‐FAV4Fs, was separated from FAdV‐4 adenoviral plasmid pKFAV4GFP. An overlap extension polymerase chain reaction (PCR) was employed for fiber modification in pMD‐FAV4Fs, and the modified fibers were restored to generate new adenoviral plasmids through restriction‐assembly. FAdV‐4 vectors were rescued and amplified in chicken LMH cells. Fluorescence microscopy and flow cytometry were used to evaluate the gene transfer efficiency. The amount of viruses binding to cells was determined by a real‐time PCR. A plaque‐forming assay and one‐step growth curve were used to evaluate virus growth. Results: Four sites in the CD‐, DE‐, HI‐ and IJ‐loop of fiber1 knob could tolerate the insertion of exogenous peptide. The insertion of RGD4C peptide in the fiber1 knob significantly promoted FAdV‐4 transduction to human adherent cells such as 293, A549 and HEp‐2, and the insertion to the IJ‐loop demonstrated the best performance. The replacement of the fiber2 knob of FAdV‐4 with that of HAdV‐35 improved the gene transfer to human suspension cells such as Jurkat, K562 and U937. Fiber‐modified FAdV‐4 vectors could transduce approximately 80% human cells at an acceptable multiplicity of infection. Enhanced gene transfer mainly resulted from increased virus binding. Fiber modifications did not significantly influence the growth of recombinant FAdV‐4 in packaging cells. Conclusions: As a proof of principle, it was feasible to enhance gene transduction of FAdV‐4 vectors to human cells by modifying the fibers. [ABSTRACT FROM AUTHOR]
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- 2021
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17. The natural course of COVID‐19 patients without clinical intervention.
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Wu, Daxian, Rao, Qunfang, and Zhang, Wenfeng
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COVID-19 ,COMPUTED tomography ,LYMPHOCYTE count ,ALANINE aminotransferase ,ASPARTATE aminotransferase - Abstract
The natural course of coronavirus disease 2019 (COVID‐19) patients without clinical intervention has not yet been documented. One hundred and fifty‐eight patients from two hospitals were enrolled to identify the indicators of severe COVID‐19 and observe the natural course of COVID‐19 patients without clinical intervention. The total computed tomography (CT) score, a quantitative score based on assessment of the number, quadrant, and area of the lesions in CT, tended to perform better than assessment based only on the number or area of the lesions (p = 0.0004 and p = 0.0887, respectively). Multivariate logistic regression showed that the total CT score, chest tightness, lymphocyte, and lactate dehydrogenase (LDH) were independent factors for severe COVID‐19. For patients admitted in 2 weeks from onset to hospitalization, the frequency of severe COVID‐19 was gradually increased with the delayed hospitalization. The symptoms of fatigue, dry cough, sputum production, chest tightness, and polypnea were gradually more frequent. The levels of C‐reactive protein, alanine aminotransferase, aspartate aminotransferase, total bilirubin, direct bilirubin, γ‐glutamyl transpeptidase, LDH, and d‐dimer were also gradually increased, as well as the scores based on CT. Conversely, the lymphocyte count and the albumin level were gradually decreased with the delayed hospitalization. Detail turning points of the above alterations were observed after 10–14 days from onset to hospitalization. Total CT score was a simple and feasible score for identifying severe COVID‐19. COVID‐19 patients without clinical intervention deteriorated gradually during the initial 10–14 days but gradually improved thereafter. Highlights: Present study developed a simple and feasible score based on CT to identify severe COVID‐19.Present study was the first to investigate the natural course of COVID‐19 patients without clinical intervention.COVID‐19 patients without clinical intervention deteriorated gradually during the initial 10‐14 days but gradually improved thereafter. [ABSTRACT FROM AUTHOR]
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- 2021
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18. Observation of the Out‐of‐Plane Polarized Spin Current from CVD Grown WTe2.
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Shi, Shuyuan, Li, Jie, Hsu, Chuang‐Han, Lee, Kyusup, Wang, Yi, Yang, Li, Wang, Junyong, Wang, Qisheng, Wu, Hao, Zhang, Wenfeng, Eda, Goki, Liang, Gengchiau, Chang, Haixin, and Yang, Hyunsoo
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SPIN-polarized currents ,CHEMICAL vapor deposition ,SEMIMETALS ,SPIN-orbit interactions ,CRYSTAL structure - Abstract
Weyl semimetal Td‐phase WTe2 possesses the spin‐resolved band structure with strong spin–orbit coupling, holding promises as a useful spin source material. The noncentrosymmetric crystalline structure of Td‐WTe2 endows the generation of the out‐of‐plane polarized spin, which is of great interest in magnetic memory applications. Previously, WTe2 was explored in spin devices based on mechanically exfoliated single crystal flakes with a size of micrometers. For practical spintronics applications, it is highly desirable to implement wafer‐scale thin films. In this work, centimeter‐scale chemical vapor deposition (CVD) grown Td‐WTe2 thin films are used and the spin current generation is studied by the spin torque ferromagnetic resonance (ST‐FMR) technique. The in‐plane and out‐of‐plane spin conductivities of 7.36 × 103 (ℏ/2e) (Ωm)–1 and 1.76 × 103 (ℏ/2e) (Ωm)–1, respectively, are found in CVD‐growth 5 nm‐WTe2. The current‐induced magnetization switching in WTe2/NiFe is demonstrated at room temperature in the domain wall motion regime, which may invigorate potential spintronic device innovations based on Weyl semimetals. [ABSTRACT FROM AUTHOR]
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- 2021
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19. Two‐Dimensional Metal Telluride Atomic Crystals: Preparation, Physical Properties, and Applications.
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Li, Hongda, Li, Chenpu, Tao, Boran, Gu, Shaonan, Xie, Yuanmiao, Wu, Hao, Zhang, Gaojie, Wang, Guofu, Zhang, Wenfeng, and Chang, Haixin
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CHEMICAL vapor deposition ,MOLECULAR beam epitaxy ,CRYSTALS ,THERMOELECTRIC materials ,SINGLE crystals ,METALS - Abstract
Atom‐thick 2D metal telluride atomic crystals (2D MTACs) display many fascinating physical properties for potential applications in multiple fields. In this review, recent advances in the preparation, physical properties and applications of 2D MTACs are presented. First, three kinds of the most available preparation methods for 2D single crystal MTACs have been summarized, including single crystal‐based mechanical exfoliation, molecular beam epitaxy, and chemical vapor deposition. Second, the recent progress on abundant physical properties of 2D MTACs is briefly introduced, including surface electronic properties, optoelectronic properties, electronic transport, and thermoelectric properties, ferroelectric properties, superconducting properties, and ferromagnetic properties. Third, the potential electronics, spintronics, optoelectronics and energy applications of 2D MTACs are presented. Finally, some significant challenges and opportunities in 2D MTACs are briefly addressed. [ABSTRACT FROM AUTHOR]
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- 2021
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20. High‐Performance Large‐Scale Vertical 1T'/2H Homojunction CVD‐Grown Polycrystalline MoTe2 Transistors.
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Xie, Zijian, Lei, Wenyu, Zhang, Wenfeng, Liu, Yuan, Yang, Li, Wen, Xiaokun, and Chang, Haixin
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POLYCRYSTALLINE semiconductors ,CHEMICAL vapor deposition ,TRANSISTORS ,EPITAXY ,TRANSITION metals - Abstract
2D transition metal dichalcogenides (TMDs) have emerged as an ideal alternative to silicon in advanced electronics. Especially, MoTe2 attracts peculiar attention since it offers a unique opportunity of resolving critical electrical contacts. Currently, although MoTe2‐based coplanar semiconductor‐metal circuitry realized by epitaxial growth and chemical assembly has been demonstrated, while still suffers from the requirement of extremely accurate synthesis process control. Here, a facile strategy is demonstrated to fabricate large scale and high performance MoTe2 transistors with a 1T'/2H vertical homojunction structure by combining a spatial and phase controlled MoTe2 scalable synthesis and a scalable universal transfer method with water‐soluble poly‐vinylpyrrolidone and poly‐(vinyl alcohol) bilayer mediator. Both high quality 1T'‐ and 2H‐ MoTe2 with controlled dimensions can be scalable synthesized via a shadow mask assisted chemical vapor deposition method. These as‐synthesized MoTe2 patterns can be successfully transferred to a wide range of substrates at a high yield >80% with well‐retained properties to construct transistors with a complex vertical 1T'/2H‐MoTe2/HfAlO2 structure. The devices exhibit an on/off current ratio surpassing 104 and a typical mobility of ≈29 cm2 V−1 s−1. The developed scaled strategy of combining both scalable MoTe2 synthesis and transfer offers a feasible way for potential MoTe2‐based large‐scale electronics. [ABSTRACT FROM AUTHOR]
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- 2021
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21. Highly Tunable Near‐Room Temperature Ferromagnetism in Cr‐Doped Layered Td‐WTe2.
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Yang, Li, Wu, Hao, Zhang, Liang, Zhang, Wenfeng, Li, Luying, Kawakami, Tappei, Sugawara, Katsuaki, Sato, Takafumi, Zhang, Gaojie, Gao, Pengfei, Muhammad, Younis, Wen, Xiaokun, Tao, Boran, Guo, Fei, and Chang, Haixin
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SEMIMETALS ,FERROMAGNETISM ,ANOMALOUS Hall effect ,MAGNETIC moments ,MAGNETIC fields ,CURIE temperature ,MAGNETORESISTANCE - Abstract
The discovery of type‐II Weyl semimetal states in layered transition metal dichalcogenides Td‐WTe2 indicates great potential for novel electronic, spintronic, and quantum devices. Theoretically, the interaction between the topological states and the magnetic ordered states of Td‐WTe2 enables the modulation of Weyl semimetal states by an external magnetic field. However, currently, ferromagnetism in layered Td‐WTe2 is still elusive and rarely observed. In this research, ferromagnetic order into WTe2 using magnetic chromium (Cr) doping with a two‐step Te flux strategy is introduced. The Curie temperature (Tc) and the ferromagnetic moment are well tuned with a Cr doping concentration. The Tc of the Cr‐doped layered Td‐WTe2 could be regulated from 182 to 283 K, which is close to room temperature. The saturation magnetic moment could be changed from 2.26 to 4.20 emu g–1, which is stronger than most values reported for these materials. Most intriguingly, the Cr‐doped layered Td‐WTe2 single crystals still exhibit semimetallic behavior and they possess very large magnetoresistance with obvious Shubnikov de Haas (SdH) quantum oscillations and an anomalous Hall effect. The findings offer feasible ways to induce and tune ferromagnetic orders in layered Td‐WTe2 and thus to control its topological phase with external magnetic fields. [ABSTRACT FROM AUTHOR]
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- 2021
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22. Two‐Dimensional Metal‐Halide Perovskite‐based Optoelectronics: Synthesis, Structure, Properties and Applications.
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Li, Hongda, Luo, Tianyuan, Zhang, Shoufeng, Sun, Zijun, He, Xiong, Zhang, Wenfeng, and Chang, Haixin
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PEROVSKITE ,OPTOELECTRONICS ,METAL halides - Abstract
In the past decade, metal‐halide perovskites have attracted increasing attention in optoelectronics, due to their superior optoelectronic properties. However, inherent instabilities of conventional three‐dimensional (3D) perovskites over moisture, heat, and light remain a severe challenge before the realization of commercial application of metal‐halide perovskites. Interestingly, when the dimensions of metal‐halide perovskites are reduced to two dimensions (2D), many of the novel properties will arise, such as enlarged bandgap, high photoluminescence quantum yield, and large exciton binding energy. As a result, 2D metal‐halide perovskite‐based optoelectronic devices display excellent performance, particularly as ambient stable solar cells with excellent power conversion efficiency (PCE), high‐performance light‐emitting diodes (LEDs) with sharp emission peak, and high‐sensitive photodetectors. In this review, we first introduce the synthesis, structure, and physical properties of 2D perovskites. Then, the 2D perovskite‐based solar cells, LEDs, and photodetectors are discussed. Finally, a brief overview of the opportunities and challenges for 2D perovskite optoelectronics is presented. [ABSTRACT FROM AUTHOR]
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- 2021
- Full Text
- View/download PDF
23. Exosomes from miRNA‐126‐modified endothelial progenitor cells alleviate brain injury and promote functional recovery after stroke.
- Author
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Wang, Jinju, Chen, Shuzhen, Zhang, Wenfeng, Chen, Yanfang, and Bihl, Ji C.
- Subjects
VASCULAR endothelial growth factor receptors ,PROGENITOR cells ,ENDOTHELIAL cells ,BRAIN injuries ,EXOSOMES - Abstract
Aims: We previously showed that the protective effects of endothelial progenitor cells (EPCs)‐released exosomes (EPC‐EXs) on endothelium in diabetes. However, whether EPC‐EXs are protective in diabetic ischemic stroke is unknown. Here, we investigated the effects of EPC‐EXs on diabetic stroke mice and tested whether miR‐126 enriched EPC‐EXs (EPC‐EXsmiR126) have enhanced efficacy. Methods: The db/db mice subjected to ischemic stroke were intravenously administrated with EPC‐EXs 2 hours after ischemic stroke. The infarct volume, cerebral microvascular density (MVD), cerebral blood flow (CBF), neurological function, angiogenesis and neurogenesis, and levels of cleaved caspase‐3, miR‐126, and VEGFR2 were measured on day 2 and 14. Results: We found that (a) injected EPC‐EXs merged with brain endothelial cells, neurons, astrocytes, and microglia in the peri‐infarct area; (b) EPC‐EXsmiR126 were more effective than EPC‐EXs in decreasing infarct size and increasing CBF and MVD, and in promoting angiogenesis and neurogenesis as well as neurological functional recovery; (c) These effects were accompanied with downregulated cleaved caspase‐3 on day 2 and vascular endothelial growth factor receptor 2 (VEGFR2) upregulation till day 14. Conclusion: Our results indicate that enrichment of miR126 enhanced the therapeutic efficacy of EPC‐EXs on diabetic ischemic stroke by attenuating acute injury and promoting neurological function recovery. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
24. Rear‐Illuminated Perovskite Photorechargeable Lithium Battery.
- Author
-
Gurung, Ashim, Reza, Khan Mamun, Mabrouk, Sally, Bahrami, Behzad, Pathak, Rajesh, Lamsal, Buddhi Sagar, Rahman, Sheikh Ifatur, Ghimire, Nabin, Bobba, Raja Sekhar, Chen, Ke, Pokharel, Jyotshna, Baniya, Abiral, Laskar, Md Ashiqur Rahman, Liang, Mao, Zhang, Wenfeng, Zhang, Wen‐Hua, Yang, Shangfeng, Xu, Kang, and Qiao, Qiquan
- Subjects
ENERGY storage ,LITHIUM cells ,BATTERY management systems ,PLUG-in hybrid electric vehicles ,ENERGY harvesting ,PEROVSKITE ,ELECTRIC vehicle batteries ,MONOLITHIC reactors - Abstract
Photovoltaic power‐conversion systems can harvest energy from sunlight almost perpetually whenever sunrays are accessible. Meanwhile, as indispensable energy storage units used in advanced technologies such as portable electronics, electric vehicles, and renewable/smart grids, batteries are energy‐limited closed systems and require constant recharging. Fusing these two essential technologies into a single device would create a sustainable power source. Here, it is demonstrated that such an integrated device can be realized by fusing a rear‐illuminated single‐junction perovskite solar cell with Li4Ti5O12‐LiCoO2 Li‐ion batteries, whose photocharging is enabled by an electronic converter via voltage matching. This design facilitates a straightforward monolithic stacking of the battery on the solar cell using a common metal substrate, which provides a robust mechanical isolation between the two systems while simultaneously providing an efficient electrical interconnection. This system delivers a high overall photoelectric conversion‐storage efficiency of 7.3%, outperforming previous efforts on stackable integrated architectures with organic–inorganic photovoltaics. Furthermore, converter electronics facilitates system control with battery management and maximum power point tracking, which are inevitable for efficient, safe, and reliable operation of practical loads. This work presents a significant advancement toward integrated photorechargeable energy storage systems as next‐generation power sources. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
25. Surface Passivation of Perovskite Film by Sodium Toluenesulfonate for Highly Efficient Solar Cells.
- Author
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Zhang, Mengmeng, Hu, Wanpei, Shang, Yanbo, Zhou, Weiran, Zhang, Wenfeng, and Yang, Shangfeng
- Subjects
SILICON solar cells ,SURFACE passivation ,SOLAR cells ,PEROVSKITE ,ELECTRON traps ,VALENCE bands - Abstract
Ionic defects at the surfaces of organolead halide perovskite films are detrimental to both the efficiency and stability of perovskite solar cells (PSCs). Herein, sodium p‐toluenesulfonate (STS) is applied during the surface modification of perovskite layer for the first time, leading to the efficient surface passivation of the perovskite film and consequently significant enhancements in both efficiency and stability of mixed‐cation PSC devices. Upon incorporating STS atop the perovskite layer, the power conversion efficiency of the Cs0.05MA0.12FA0.83PbI2.55Br0.45 (abbreviated as CsMAFA) mesoporous‐structure mixed‐cation PSC devices improves from 18.70% to 20.05% with reduced hysteresis. The sulfonate (–SO3−) anion of STS coordinates with the Pb2+ of CsMAFA perovskite, and the Na+ cation of STS electrostatically interacts with the anions (I−/Br−) of CsMAFA perovskite, resulting in the surface passivation of the CsMAFA perovskite film with reduced electron and hole trap state densities. In addition, STS modification induces an upshift of the valence band of perovskite, facilitating hole extraction from the perovskite layer to the hole transport layer with suppressed interfacial charge recombination. Moreover, such a trap state passivation of perovskite film leads to improvement of the ambient stability of PSC devices. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
26. Global Response of Evapotranspiration Ratio to Climate Conditions and Watershed Characteristics in a Changing Environment.
- Author
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Liu, Zhiyong, Cheng, Linyin, Zhou, Guoyi, Chen, Xiaohong, Lin, Kairong, Zhang, Wenfeng, Chen, Xiuzhi, and Zhou, Ping
- Subjects
EVAPOTRANSPIRATION ,WATERSHEDS ,CLIMATE change ,GLOBAL warming ,METEOROLOGICAL precipitation - Abstract
Understanding the complex relationship between evapotranspiration and climate conditions and land surface characteristics is important within the context of global warming and increasing anthropogenic stressors. Based on the Budyko theory, we derived general frameworks for describing how the evapotranspiration ratio (actual evapotranspiration/precipitation, AET/P) responds to changes in the aridity index (potential evapotranspiration/precipitation, PET/P) and watershed characteristics (m). The frameworks show that the sensitivity of AET/P to PET/P decreases with increasing aridity but such decreasing pattern also depends on different watershed characteristics. The sensitivity coefficient tends to be greater in the energy‐limited regimes (above 0.3) than in the water‐limited regimes. The slope of the sensitivity curve becomes steeper for larger m values (e.g., m > 2). In addition, the sensitivity of the AET/P to m shows an asymmetrical unimodal curve, while the strongest sensitivity (inflection point) of evapotranspiration ratio to m occurs at PET/P > 1. We further examined spatial patterns of these sensitivities and the relative roles of PET/P (RCPET/P) and m (RCm) to AET/P over 91 hydrological basins worldwide. The tropical humid basins present the strongest sensitivity of AET/P to PET/P, while higher sensitivity coefficients of AET/P to m can be found in very cold basins. The changes in the sensitivity of evapotranspiration ratio to PET/P and m between 1930–1970 and 1971–2008 were assessed for these basins across broad climatic gradients. Most of these basins show a positive change in RCPET/P but a negative shift in RCm in the warming world. Key Points: General frameworks are derived to describe how the evapotranspiration ratio responds to the aridity index and watershed characteristicsSensitivity of the evapotranspiration ratio to watershed characteristics (m) shows an asymmetrical unimodal curveSpatial patterns of these sensitivity coefficients and the relative roles of PET/P and m to AET/P over global basins were identified [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
27. Influence of Sn, Cd, and Si addition on the electrochemical performance of Al–Zn–In sacrificial anodes.
- Author
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Xia, Zijie, Zhang, Wenfeng, Yang, Xiaowei, Chen, Tao, Zhu, Yunfeng, Ma, Huaxiong, and Li, Liquan
- Subjects
- *
ALUMINUM alloys , *TIN alloys , *CATHODIC protection , *MICROSCOPY , *ALLOYS , *ANODES , *MICROSTRUCTURE - Abstract
Overcoming the reduction of current efficiency and stacking of corrosion products on the surface of Al–Zn–In sacrificial anodes after long‐term use is of great significance for Al–Zn–In alloy as an anode material for cathodic protection of steel structures in seawater. In this study, four different sacrificial anode materials were prepared based on the Al‐6Zn‐0.03In (wt%) alloy without and with the addition of alloying elements of Sn, Cd, and Si, respectively. The influence of the addition of Sn, Cd, and Si on the microstructure and electrochemical performance of the Al–Zn–In anode was investigated by optical microscopy and electrochemical measurements. The results show that the introduction of Sn, Cd, and Si changes the microdendrite structure of Al–Zn–In to equiaxed grain. The added Sn, Cd, and Si alloys have more negative and stable working potential and uniformly dissolved morphology. The actual capacity and current efficiency of aluminum alloys increase from 2,000.6 Ah/kg and 70.7% of Al–Zn–In alloy to 2,539.4 Ah/kg and 88.6% of Al–Zn–In–Sn, 2,437.3 Ah/kg and 85.5% of Al–Zn–In–Cd and 2,500.4 Ah/kg and 88.8% of Al–Zn–In–Si alloys, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
28. Enhanced Performance of Perovskite Solar Cells via Low‐Temperature‐Processed Mesoporous SnO2.
- Author
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Wang, Qiyun, Peng, Changtao, Du, Lin, Li, Haijin, Zhang, Wenfeng, Xie, Jiale, Qi, Hongchang, Li, Yuepeng, Tian, Liuwen, and Huang, Yuelong
- Subjects
SOLAR cells ,PEROVSKITE ,ELECTRON transport ,NANOCRYSTALS ,PRODUCTION sharing contracts (Oil & gas) ,NATURAL products - Abstract
Perovskite solar cells (PSCs) based on planar SnO2 (p‐SnO2) demonstrate excellent performance due to the superior properties of SnO2 as electron transporting layer (ETL). However, at present mesoporous SnO2 (m‐SnO2) still lags behind p‐SnO2 due to problems in the fabrication process of m‐SnO2. In this paper, a new strategy for preparing m‐SnO2 ETL is introduced which owns two valuable features: First, it applies a low temperature process to make mesoporous structure, which favors preserving the pristine properties of the raw SnO2 nanocrystals. Second, the degree of porosity and roughness of the m‐SnO2 layer can be well controlled, making it friendly to the following deposition process of PSCs. The performance of the PSCs based on the m‐SnO2 ETL prepared from this strategy shows an obvious improvement which is mainly from the improvement in Jsc and FF, suggesting a higher carrier collection efficiency for the m‐SnO2 ETL. The relevant characterizations including PL, TRPL, EIS, and KPFM confirm that the m‐SnO2 ETL possesses stronger electron extraction capability than the p‐SnO2 ETL. Hence, the proposed strategy can manifest the advantages of m‐SnO2 ETL meanwhile refrain its negative impacts, and thus promote the progress of the m‐SnO2 ETL‐based PSCs. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
29. Identification of prognostic biomarkers for breast cancer based on miRNA and mRNA co‐expression network.
- Author
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Yao, Yan, Liu, Ruijuan, Gao, Chundi, Zhang, Tingting, Qi, Lingyu, Liu, Gongxi, Zhang, Wenfeng, Wang, Xue, Li, Jie, Li, Jia, and Sun, Changgang
- Published
- 2019
- Full Text
- View/download PDF
30. Room‐Temperature Nanoseconds Spin Relaxation in WTe2 and MoTe2 Thin Films.
- Author
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Wang, Qisheng, Li, Jie, Besbas, Jean, Hsu, Chuang‐Han, Cai, Kaiming, Yang, Li, Cheng, Shuai, Wu, Yang, Zhang, Wenfeng, Wang, Kaiyou, Chang, Tay‐Rong, Lin, Hsin, Chang, Haixin, and Yang, Hyunsoo
- Abstract
Abstract: The Weyl semimetal WTe
2 and MoTe2 show great potential in generating large spin currents since they possess topologically protected spin‐polarized states and can carry a very large current density. In addition, the intrinsic non‐centrosymmetry of WTe2 and MoTe2 endows with a unique property of crystal symmetry‐controlled spin–orbit torques. An important question to be answered for developing spintronic devices is how spins relax in WTe2 and MoTe2 . Here, a room‐temperature spin relaxation time of 1.2 ns (0.4 ns) in WTe2 (MoTe2 ) thin film using the time‐resolved Kerr rotation (TRKR) is reported. Based on ab initio calculation, a mechanism of long‐lived spin polarization resulting from a large spin splitting around the bottom of the conduction band, low electron–hole recombination rate, and suppression of backscattering required by time‐reversal and lattice symmetry operation is identified. In addition, it is found that the spin polarization is firmly pinned along the strong internal out‐of‐plane magnetic field induced by large spin splitting. This work provides an insight into the physical origin of long‐lived spin polarization in Weyl semimetals, which could be useful to manipulate spins for a long time at room temperature. [ABSTRACT FROM AUTHOR]- Published
- 2018
- Full Text
- View/download PDF
31. Short Implants (5 to 8 mm) Versus Longer Implants (>8 mm) with Sinus Lifting in Atrophic Posterior Maxilla: A Meta-Analysis of RCTs.
- Author
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Fan, Tengfei, Li, Yicun, Deng, Wei‐Wei, Wu, Tianfu, and Zhang, Wenfeng
- Subjects
ALVEOLAR process ,MAXILLA ,CLINICAL trials ,DENTAL implants ,ORAL surgery - Abstract
ABSTRACT Objective The specific purposes of this study were (1) to undertake a thorough systematic review and meta-analysis based only on randomized clinical trials (RCTs) to compare the rates of survival and complications of short implants to those of long implants; (2) to compare the surgical time and cost of short implants to those of long implants. Methods RCTs were identified from the major electronic databases (MEDLINE, Embase and Cochrane Library) using the keywords 'dental implant,' 'short implant' and 'atrophic maxilla,' and a quantitative meta-analysis was conducted. The survival rate of implants and complications were the primary outcome measures, and other parameters assessed included costs and surgical time. Results Seven RCTs that met the inclusion criteria included 554 implants (265 implants in the short implant group). There was no significant difference in survival rate between two groups (RR: 1.00; 95% CI: [0.97, 1.03]; p = .96; seven trials, 554 participants). Compared with long implant group, the short implant group had a lower complications and the effect measure was significant (RR: 0.58; 95% CI: [0.37, 0.90]; p = .02; seven trials, 554 participants). Conclusion This systematic review showed that no difference between the survival rates of short implants (5-8 mm) and long implants (>8 mm); complications in short implants are lower than that in long implants. However, further studies are required to substantiate our findings. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
32. 3D Bicontinuous Nanoporous Reduced Graphene Oxide for Highly Sensitive Photodetectors.
- Author
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Ito, Yoshikazu, Zhang, Wenfeng, Li, Jinhua, Chang, Haixin, Liu, Pan, Fujita, Takeshi, Tan, Yongwen, Yan, Feng, and Chen, Mingwei
- Subjects
- *
NANOPOROUS materials , *NANOSTRUCTURED materials , *GRAPHENE oxide , *OPTOELECTRONIC device performance , *PHOTODETECTORS - Abstract
Reduced graphene oxide (RGO) is an important graphene derivative for applications in photonics and optoelectronics because of the band gap created by chemical oxidation. However, most RGO materials made by chemically exfoliated graphite oxide are 2D flakes. Their optoelectronic performance deteriorates significantly as a result of weak light-matter interaction and poor electrical contact between stacking flakes. Here we report a bicontinuous 3D nanoporous RGO (3D np-RGO) with high optoelectronic performance for highly sensitive photodetectors. 3D np-RGO demonstrates a over 40 times higher light absorption than monolayer graphene materials and at least two orders of magnitude higher electron mobility than conventional RGO from discrete RGO flakes. The np-RGO with an optimal reduction state shows ultrahigh photoresponse of 3.10 3 104 A W−1 at room temperature, approximately four orders of magnitude higher than graphene and other graphene derivatives at similar levels of light intensity radiations, and the excellent external quantum efficiency of 1.04 3 107% better than commercial silicon photodetector. The ultrahigh capability of conversing photons to photocurrent originates from strongly enhanced light absorption, facilitated photocarrier transport, and tunable oxygenous defects and reduction states in the 3D interconnected bicontinuous RGO network. [ABSTRACT FROM AUTHOR]
- Published
- 2016
- Full Text
- View/download PDF
33. Optimization of microwave-assisted extraction for six inorganic and organic arsenic species in chicken tissues using response surface methodology.
- Author
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Zhang, Wenfeng, Hu, Yuanan, and Cheng, Hefa
- Subjects
- *
ARSENIC analysis , *TISSUE extracts , *TISSUE analysis , *HIGH performance liquid chromatography , *INDUCTIVELY coupled plasma mass spectrometry - Abstract
Response surface methodology was applied to optimize the parameters for microwave-assisted extraction of six major inorganic and organic arsenic species (As(III), As(V), dimethyl arsenic acid, monomethyl arsenic acid, p-arsanilic acid, and roxarsone) from chicken tissues, followed by detection using a high-performance liquid chromatography with inductively coupled mass spectrometry detection method, which allows the simultaneous analysis of both inorganic and organic arsenic species in the extract in a single run. Effects of extraction medium, solution pH, liquid-to-solid ratio, and the temperature and time of microwave-assisted extraction on the extraction of the targeted arsenic species were studied. The optimum microwave-assisted extraction conditions were: 100 mg of chicken tissue, extracted by 5 mL of 22% v/v methanol, 90 mmol/L (NH4)2HPO4, and 0.07% v/v trifluoroacetic acid (with pH adjusted to 10.0 by ammonium hydroxide solution), ramping for 10 min to 71°C, and holding for 11 min. The method has good extraction performance for total arsenic in the spiked and nonspiked chicken tissues (104.0 ± 13.8% and 91.6 ± 7.8%, respectively), except for the ones with arsenic contents close to the quantitation limits. Limits of quantitation (S/N = 10) for As(III), As(V), dimethyl arsenic acid, monomethyl arsenic acid, p-arsanilic acid, and roxarsone in chicken tissues using this method were 0.012, 0.058, 0.039, 0.061, 0.102, and 0.240 mg/kg (dry weight), respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
34. O2‐10‐03: LEVERAGING TISSUE SPECIFIC GENE EXPRESSION REGULATION TO IDENTIFY GENES ASSOCIATED WITH ALZHEIMER'S DISEASE.
- Author
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Liu, Wei, Li, Mo, Zhang, Wenfeng, Zhou, Geyu, Wu, Xing, Wang, Jiawei, and Zhao, Hongyu
- Published
- 2019
- Full Text
- View/download PDF
35. Leptin modulates olfactory discrimination and neural activity in the olfactory bulb.
- Author
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Sun, Changcheng, Tang, Keke, Wu, Jing, Xu, Han, Zhang, Wenfeng, Cao, Tiantian, Zhou, Yang, Yu, Tian, and Li, Anan
- Subjects
OLFACTORY bulb ,LEPTIN ,PEPTIDE hormones ,GRANULE cells ,POTASSIUM channels ,OLFACTORY perception - Abstract
Aim: Leptin is an important peptide hormone that regulates food intake and plays a crucial role in modulating olfactory function. Although a few previous studies have investigated the effect of leptin on odor perception and discrimination in rodents, research on the neural basis underlying the behavioral changes is lacking. Here we study how leptin affects behavioral performance during a go/no‐go task and how it modulates neural activity of mitral/tufted cells in the olfactory bulb, which plays an important role in odor information processing and representation. Methods: A go/no‐go odor discrimination task was used in the behavioral test. For in vivo studies, single unit recordings, local field potential recordings and fiber photometry recordings were used. For in vitro studies, we performed patch clamp recordings in the slice of the olfactory bulb. Results: Behaviorally, leptin affects performance and reaction time in a difficult odor‐discrimination task. Leptin decreases the spontaneous firing of single mitral/tufted cells, decreases the odor‐evoked beta and high gamma local field potential response, and has bidirectional effects on the odor‐evoked responses of single mitral/tufted cells. Leptin also inhibits the population calcium activity in genetically identified mitral/tufted cells and granule cells. Furthermore, in vitro slice recordings reveal that leptin inhibits mitral cell activity through direct modulation of the voltage‐sensitive potassium channel. Conclusions: The behavioral reduction in odor discrimination observed after leptin administration is likely due to decreased neural activity in mitral/tufted cells, caused by modulation of potassium channels in these cells. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
36. Ta Doping Enhanced Room‐Temperature Ferromagnetism in 2D Semiconducting MoTe2 Nanosheets.
- Author
-
Yang, Li, Wu, Hao, Zhang, Wenfeng, Lou, Xun, Xie, Zijian, Yu, Xu, Liu, Yuan, and Chang, Haixin
- Subjects
FERROMAGNETISM ,FERROMAGNETIC materials ,TRANSITION metals ,ELECTRONIC structure ,CHARGE carriers - Abstract
Room temperature ferromagnetic semiconductors remain one of the most puzzling issues to be solved in tens of years. Nowadays, 2D ferromagnetic transition metal dichalcogenides (TMDCs) nanosheets attract continuous interest due to their exceptional electronic structure and properties. Here, it is identified that semiconducting 2H‐phase MoTe2 few/mono‐layer mixed nanosheets present a room temperature ferromagnetic property with Curie temperature above 400 K, although the MoTe2 bulk counterpart shows diamagnetic properties. The origin of such observed room temperature ferromagnetism is attributed to the combination of their structural defects including Te vacancies, disorders, and amorphous imperfections and edge‐states caused by reduced dimensionality. Moreover, a distinct enhancement of ferromagnetic properties at room temperature is revealed by a non‐magnetic Ta doping strategy. Such structural defects and edge‐states modulated ferromagnetism offers a feasible strategy to search for more robust room temperature ferromagnetic TMDCs nanosheets, which is essential to explore novel electronic and spintronic devices where both carrier charge and spin freedom can be controlled. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
37. Tunable High‐Temperature Tunneling Magnetoresistance in All‐van der Waals Antiferromagnet/Semiconductor/Ferromagnet Junctions.
- Author
-
Jin, Wen, Li, Xinlu, Zhang, Gaojie, Wu, Hao, Wen, Xiaokun, Yang, Li, Yu, Jie, Xiao, Bichen, Guo, Fei, Zhang, Wenfeng, Zhang, Jia, and Chang, Haixin
- Abstract
Magnetic tunnel junctions (MTJs) are widely applied in spintronic devices for efficient spin detection through the imbalance of spin polarization at the Fermi level. The van der Waals (vdW) property of 2D magnets with atomically flat surfaces and negligible surface roughness greatly facilitates the development of MTJs, primarily in ferromagnets. Here, A‐type antiferromagnetism in 2D vdW single‐crystal (Fe0.8Co0.2)3GaTe2 is reported with TN ≈ 203 K in bulk and ≈ 185 K in 9‐nm nanosheets. The metallic nature and out‐of‐plane magnetic anisotropy make it a suitable candidate for MTJ electrodes. By constructing heterostructures based on (Fe0.8Co0.2)3GaTe2/WSe2/Fe3GaTe2, a large tunneling magnetoresistance (TMR) ratio of 180% at low temperature is obtained, with the TMR signal persisting at near‐room temperature 280 K. Furthermore, the TMR is tunable by the electric field, and the MTJ device operates stably with a low applied bias down to 1 mV (≈0.6 nA), highlighting its potential for energy‐efficient spintronic devices. This work opens up new opportunities for 2D antiferromagnetic spintronics and quantum devices. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
38. Molecular Beam Epitaxy Scalable Growth of Wafer‐Scale Continuous Semiconducting Monolayer MoTe2 on Inert Amorphous Dielectrics.
- Author
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He, Qingyuan, Li, Pengji, Wu, Zhiheng, Yuan, Bin, Luo, Zhongtao, Yang, Wenlong, Liu, Jie, Cao, Guoqin, Zhang, Wenfeng, Shen, Yonglong, Zhang, Peng, Liu, Suilin, Shao, Guosheng, and Yao, Zhiqiang
- Published
- 2019
- Full Text
- View/download PDF
39. Cathepsin B regulates non‐canonical NLRP3 inflammasome pathway by modulating activation of caspase‐11 in Kupffer cells.
- Author
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Chen, Nan, Ou, Zhibing, Zhang, Wenfeng, Zhu, Xiwen, Li, Peizhi, and Gong, Jianping
- Subjects
CATHEPSIN B ,INFLAMMASOMES ,CASPASES ,KUPFFER cells ,PHARMACOLOGY ,GENE silencing - Abstract
Objectives: The non‐canonical inflammasome pathway was described which engages caspase‐11 to mediate pyroptosis and the subsequent release of IL‐1α, IL‐1β and IL‐18 in TLR4‐independent way. Cathepsin B is capable of activating caspase‐11 under cell‐free conditions which may regulate non‐canonical NLRP3 inflammasome pathway. In this study, we aimed to further investigate cathepsin B as potential activators of proinflammatory caspases which may be released upon proinflammatory stimuli and regulate non‐canonical NLRP3 inflammasome pathway by modulating the activity of caspase‐11. Methods: Pharmacological and gene‐silencing approaches were used to evaluate the impact of cathepsin B on regulating non‐canonical NLRP3 inflammasome pathway in wild‐type and TLR4–/– Kupffer cells. A sepsis model was also created to investigate the effect of cathepsin B on survival. Meanwhile, cathepsin B activity and the expression level of caspase‐4 were detected in human peripheral blood mononuclear cells (PBMC) which were separated from patients suffered from SIRS or sepsis and healthy volunteers. Results: LPS stimulation caused cathepsin B activity and caspase‐11 expression increase in TLR4–/– mice. Cathepsin B activity inhibition reduced the activation of caspase‐11 and inflammasome and benefited survival in TLR4–/– mice. Upregulation of cathepsin B activity and caspase‐4 activation was found in PBMC of patients with SIRS or sepsis. Conclusion: Our results suggest a critical role for cathepsin B as activators of proinflammatory caspases‐11 and the regulatory effect in LPS‐induced caspases‐11‐dependent necrosis. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
40. Robust Magnetic Proximity Induced Anomalous Hall Effect in a Room Temperature van der Waals Ferromagnetic Semiconductor Based 2D Heterostructure.
- Author
-
Wu, Hao, Yang, Li, Zhang, Gaojie, Jin, Wen, Xiao, Bichen, Zhang, Wenfeng, and Chang, Haixin
- Abstract
Developing novel high‐temperature van der Waals ferromagnetic semiconductor materials and investigating their interface coupling effects with 2D topological semimetals are pivotal for advancing next‐generation spintronic and quantum devices. However, most van der Waals ferromagnetic semiconductors exhibit ferromagnetism only at low temperatures, limiting the proximity research on their interfaces with topological semimetals. Here, an intrinsic, van der Waals layered room‐temperature ferromagnetic semiconductor crystal, FeCr0.5Ga1.5Se4 (FCGS), is reported with a Curie temperature (TC) as high as 370 K, setting a new record for van der Waals ferromagnetic semiconductors. The saturation magnetization at low temperature (2 K) and room temperature (300 K) reaches 8.2 and 2.7 emu g−1, respectively. Furthermore, FCGS possesses a bandgap of ≈1.2 eV, which is comparable to the widely used commercial silicon. The FCGS/graphene 2D heterostructure exhibits an impeccably smooth and gapless interface, thereby inducing a robust van der Waals magnetic proximity coupling effect between FCGS and graphene. After the proximity coupling, graphene undergoes a charge carrier transition from electrons to holes, accompanied by a transition from non‐magnetic to ferromagnetic transport behavior with robust anomalous Hall effect (AHE). Notably, the van der Waals magnetic proximity‐induced AHE remains robust even up to 400 K. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
41. ChemInform Abstract: Synthesis of High Quality Two-Dimensional Materials via Chemical Vapor Deposition.
- Author
-
Yu, Jingxue, Li, Jie, Zhang, Wenfeng, and Chang, Haixin
- Published
- 2016
- Full Text
- View/download PDF
42. Highly Tunable Near‐Room Temperature Ferromagnetism in Cr‐Doped Layered Td‐WTe2.
- Author
-
Yang, Li, Wu, Hao, Zhang, Liang, Zhang, Wenfeng, Li, Luying, Kawakami, Tappei, Sugawara, Katsuaki, Sato, Takafumi, Zhang, Gaojie, Gao, Pengfei, Muhammad, Younis, Wen, Xiaokun, Tao, Boran, Guo, Fei, and Chang, Haixin
- Subjects
- *
SEMIMETALS , *FERROMAGNETISM , *ANOMALOUS Hall effect , *MAGNETIC moments , *MAGNETIC fields , *CURIE temperature , *MAGNETORESISTANCE - Abstract
The discovery of type‐II Weyl semimetal states in layered transition metal dichalcogenides Td‐WTe2 indicates great potential for novel electronic, spintronic, and quantum devices. Theoretically, the interaction between the topological states and the magnetic ordered states of Td‐WTe2 enables the modulation of Weyl semimetal states by an external magnetic field. However, currently, ferromagnetism in layered Td‐WTe2 is still elusive and rarely observed. In this research, ferromagnetic order into WTe2 using magnetic chromium (Cr) doping with a two‐step Te flux strategy is introduced. The Curie temperature (Tc) and the ferromagnetic moment are well tuned with a Cr doping concentration. The Tc of the Cr‐doped layered Td‐WTe2 could be regulated from 182 to 283 K, which is close to room temperature. The saturation magnetic moment could be changed from 2.26 to 4.20 emu g–1, which is stronger than most values reported for these materials. Most intriguingly, the Cr‐doped layered Td‐WTe2 single crystals still exhibit semimetallic behavior and they possess very large magnetoresistance with obvious Shubnikov de Haas (SdH) quantum oscillations and an anomalous Hall effect. The findings offer feasible ways to induce and tune ferromagnetic orders in layered Td‐WTe2 and thus to control its topological phase with external magnetic fields. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
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