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Chinese Chemical Letters 2008年第5期19卷 565-568页

作者： ling li wu Wei Zhao Quan Min li College of Chemistry and Environmental Science Henan Normal UniversityThe Key Laboratory of Environmental Pollution Control Technology of Henan province Xinxiang 453007 China Henan Radio and Television University Zhengzhou 450008 China

A new method was developed for the determination of cefradine by extraction-flotation of CuSCN. The experiment indicated that in the presence of 0.20 mol/L NaOH the degradation of cefradine took place in water bath at 100 ℃. The thiol group （-SH） of the degradation product could reduce Cu（Ⅱ） to Cu（Ⅰ） for the formation of the emulsion CuSCN in the presence of NH4SCN at pH 4.0. By determining the residual amount of Cu（Ⅱ） in the solution and calculating the flotation yield of Cu（Ⅱ）, the indirect determination of cefradine can be obtained. This method has been applied to determine cefradine in capsules, human serum and urine samples, respectively.

关键词： Cefradine Copper(Ⅱ) n-Propyl alcohol Extraction-flotation

A novel method for the spectrophotometric determination of cefradine by using sodium nitroprusside as chromogenic reagent

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Chinese Chemical Letters 2008年第12期19卷 1470-1474页

作者： Hua Zhang ling li wu Quan Min li Xin Zhen Du College of Chemistry and Environmental Science Henan Normal University Xinxiang 453007 China College of Chemistry and Chemical Engineering Northwest Normal University Lanzhou 730070 China Henan Radio and Television University Zhengzhou 453008 China

A novel method is developed for the determination of cefradine by using sodium nitroprusside as chromogenic reagent. The experiment indicates that a russety product is formed by the reaction of cefradine with sodium nitroprusside in basic solution, and the maximum absorption wavelength （λmax） of russety product is 505 rim. And the sensitization of tetradecyl benzyl dimethyl ammonium chloride for the reaction of cefradine with sodium nitroprusside is remarkable, The apparent molar absorption coefficient （5505） is 2.81 × 103 L/mol cm. The linear equation isA = 0.0657 ＋ 0.00804C （μg/mL） in the range of 1.50-55.0μg/mL of cefradine with a correlation coefficient r = 0.9992, and the detection limit is 1.38 p,g/mL. This method has been applied to determine cefradine in capsule and tablet samples.

关键词： Cefradine Sodium nitroprusside Chromogenic reagent Spectrophotometry

Unmanned Ship Identification Based on Improved YOLOv8s Algorithm

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Computers, Materials & Continua 2024年第3期78卷 3071-3088页

作者： Chun-Ming wu Jin Lei wu-Kai liu Mei-ling Ren ling-li Ran Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology School of Electrical EngineeringNortheast Electric Power UniversityJilin132012China School of Biomedical Engineering Taiyuan University of TechnologyTaiyuan030600China

Aiming at defects such as low contrast in infrared ship images,uneven distribution of ship size,and lack of texture details,which will lead to unmanned ship leakage misdetection and slow detection,this paper proposes an infrared ship detection model based on the improved YOLOv8 algorithm(R_YOLO).The algorithm incorporates the Efficient Multi-Scale Attention mechanism(EMA),the efficient Reparameterized Generalized-feature extraction module(CSPStage),the small target detection header,the Repulsion Loss function,and the context aggregation block(CABlock),which are designed to improve the model’s ability to detect targets at multiple scales and the speed of model *** algorithm is validated in detail on two vessel *** comprehensive experimental results demonstrate that,in the infrared dataset,the YOLOv8s algorithm exhibits improvements in various performance ***,compared to the baseline algorithm,there is a 3.1%increase in mean average precision at a threshold of 0.5(mAP(0.5)),a 5.4%increase in recall rate,and a 2.2%increase in mAP(0.5:0.95).Simultaneously,while less than 5 times parameters,the mAP(0.5)and frames per second(FPS)exhibit an increase of 1.7%and more than 3 times,respectively,compared to the CAA_YOLO ***,the evaluation indexes on the visible light data set have shown an average improvement of 4.5%.

关键词： Unmanned ships R_YOLO EMA CSPStage YOLOv8s

Hole-Transporting Materials with Rational Combination of Pyridine and Dibenzo[a,c]phenazine as Electron Acceptor for Dopant-Free Perovskite Solar Cells

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Chinese Journal of Chemistry 2024年第10期42卷 1100-1106页

作者： Weidong ling Fei wu Wentao Yuan linna Zhu Qianqian li Zhen li Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials Department of ChemistryWuhan UniversityWuhanHubei 430072China Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energy Faculty of Materials&EnergySouthwest UniversityChongqing400715China TaiKang Center for life and Medical Sciences Wuhan UniversityWuhanHubei 430072China

Perovskite solar cells(PSCs)have been proven to be a promising option for photovoltaic *** the aim to achieve efficient and stable PSCs,it is essential to explore dopant-free hole-transporting materials(HTMs)with high hole ***,HTMs bearing electron donor(D)-electron acceptor(A)-electron donor(D)structures have been constructed with strong intramolecular charge transfer(ICT)effect,based on rational combination of dibenzo[a,c]phenazine and pyridine as electronic acceptors and anchoring groups to perovskite ***,high hole mobility(7.31×10^(-5) cm^(2)·V^(-1)·s^(-1))and photoelectric conversion efficiency(20.45%)have been achieved by dopant-free DPyP-based *** afforded an efficient way to design HTMs with high hole mobility by adjustment of molecular configurations and electronic property of conjugated systems.

关键词： Perovskite solar cell Charge transfer Donor-acceptor systems Energy conversion Hole mobility

Biomimetic artificial islet model with vascularized microcapsule structures for durable glycemic control

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Materials Futures 2024年第3期3卷 157-167页

作者： Jingbo li Yile Fang Zhuhao wu Luoran Shang ling li Department of Endocrinology Zhongda HospitalSchool of MedicineSoutheast UniversityNanjing 210009People’s Republic of China Institute of Glucose and lipid Metabolism Southeast UniversityNanjing 210009People’s Republic of China Shanghai Xuhui Central Hospital Zhongshan-Xuhui Hospitaland the Shanghai Key Laboratory of Medical EpigeneticsThe International Co-laboratory of Medical Epigenetics and Metabolism(Ministry of Science and Technology)Institutes of Biomedical SciencesFudan UniversityShanghai 200032People’s Republic of China Department of Clinical Laboratory Nanjing Drum Tower HospitalThe Affiliated of Medical SchoolNanjing UniversityNanjing 210008People’s Republic of China

Islet transplantation is a promising strategy for diabetes mellitus treatment as it can recapitulate endogenous insulin secretion and provide long-term glycemic *** models constructed in biomaterial scaffolds that reproduce biological characteristics of native islets is a feasible option to circumvent the dilemma of donor shortage and the requirement of chronic ***,we developed bioinspired artificial microcapsule-based islet models with microvessels for glycemic control using microfluidic electrospray *** electrospray can generate uniform hydrogel microcapsules with core-shell structure for encapsulating islet *** cell-laden microcapsules enabled the efficient transportation of nutrient,oxygen,and insulin;as well as the incorporation with microvessels for prompting glucose responsiveness and molecular *** demonstrated by in vivo experiments that the blood glucose,food intake,and body weight of diabetic mouse models were alleviated,and the glucose tolerance was promoted after the engraftment of islet *** further demonstrated the improved functionality of transplanted islet model in insulin secretion,immune escape,and microcirculation using standard histological and molecular *** results indicated that the microcapsules with microvessels are promising artificial islet models and are valuable for treating diabetes.

关键词： artificial islet model microfluidics vascularization hydrogel diabetes

Electronic structure and spin state regulation of vanadium nitride via a sulfur doping strategy toward flexible zinc-air batteries

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Journal of Energy Chemistry 2024年第2期89卷 239-249,I0007页

作者： Daijie Deng Honghui Zhang Jianchun wu Xing Tang Min ling Sihua Dong li Xu Henan li Huaming li Institute for Energy Research Institute of Quantum and Sustainable TechnologySchool of Chemistry and Chemical EngineeringSchool of Materials Science and EngineeringJiangsu Province and Education Ministry Co-Sponsored Synergistic Innovation Center of Modern Agricultural EquipmentJiangsu UniversityZhenjiang 212013JiangsuChina Key Laboratory of Radio Frequency and Micro-Nano Electronics of Jiangsu Province Nanjing 210023JiangsuChina Zhenjiang Kangyuan Electrical Appliance Co. Ltd.Zhenjiang 212013JiangsuChina College of Chemical and Biological Engineering Zhejiang UniversityHangzhou 310027ZhejiangChina YTO Group Corporation Dongfanghong(Henan)Agricultural Service Technology Co. Ltd.Luoyang 471033HenanChina

Owing to the distinctive structural characteristics,vanadium nitride(VN)is highly regarded as a catalyst for oxygen reduction reaction(ORR)in zinc-air batteries(ZABs).However,VN exhibits limited intrinsic ORR activity due to the weak adsorption ability to O-containing ***,the S-doped VN anchored on N,S-doped multi-dimensional carbon(S-VN/Co/NS-MC)was constructed using the solvothermal and in-situ doping *** sulfur atoms into VN species alters the electron spin state of vanadium in the S-VN/Co/NS-MC for regulating the adsorption energy of vanadium sites to oxygen *** introduced sulfur atoms polarize the V 3d_(z)^(2) electrons,shifting spin-down electrons closer to the Fermi level in the S-VN/Co/***,the introduction of sulfur atoms into VN species enhances the adsorption energy of vanadium sites for oxygen ****OOH dissociation transitions from being unspontaneous on the VN surface to a spontaneous state on the S-doped VN ***,the ORR barrier on the S-VN/Co/NS-MC surface is *** S-VN/Co/NS-MC demonstrates a higher half-wave potential and limiting current density compared to the VN/Co/*** S-VN/Co/NS-MC-based liquid ZABs display a power density of 195.7 m W cm^(-2),a specific capacity of 815.7 m A h g^(-1),and a cycling stability exceeding 250 *** S-VN/Co/NS-MC-based flexible ZABs are successfully employed to charge both a smart watch and a mobile *** approach holds promise for advancing the commercial utilization of VN-based catalysts in ZABs.

关键词： S-doped VN Electronic structures Spin state regulation Oxygen reduction reaction Zinc-air batteries

Dynamic recrystallization mechanism, texture evolution development and mechanical characteristics of a Mg–8.7Gd–4.18Y–0.42Zr magnesium alloy by ECAP

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Progress in Natural Science:Materials International 2024年第02期34卷 376-388页

作者： ling Zhang Yinglong li School of Materials Science and Engineering Northeastern University School of Mechanical and Engineering Ningxia Institute of Science and Technology

Equal channel angle pressing is recognized for its ability to refine alloy grains and alter grain orientation, thereby achieve better mechanical performance of the magnesium alloy. This study investigates the microstructures,dynamic recrystallization mechanism, texture development, and mechanical performance of GW94K(Mg–8.7Gd–4.18Y–0.42Zr wt. %) Mg alloy following ECAP-4 passes at 400°C and 3 mm/min. Results show that when high-temperature deformation is undertaken, twin formation is suppressed while dislocation slip is facilitated, increasing dislocation density during deformation. Following ECAP deformation, the sample displayed higher fracture elongation, TYS, and UTS than the as-solutioned GW94K alloy. In particular, the GW94K alloy performed well mechanically after ECAP-4 passes, with an ultimate TYS of 231 MPa, an UTS of 290 MPa, and an elongation of 14.8 %. DDRX and shear bands induce CDRX, both of which are important in plastic deformation. as well as in modifying microstructure and grain orientation during ECAP deformation.

关键词： Equal channel angular pressing Dynamic recrystallization mechanism Mechanical performance Mg-Gd-Y-Zr alloy Magnesium alloy Texture development

Serrated flow behavior of GH536 superalloy under different loading rates at room temperature

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Rare Metals 2024年第5期43卷 2317-2323页

作者： Wen-Xiang Gao Dong Ma li-li Zhao Fan Ye ling Shao Su-Jun wu School of Materials Science and Technology Beihang UniversityBeijing100091China

Serrated flow phenomenon has been widely observed among different metals due to the potential influence on their *** tensile tests of nickel-based superalloy GH536 were carried out at loading rates of 0.06,0.60,3.60,and 36.00 mm·min^(-1)at room temperature,*** tensile stress-strain curves demonstrate repetitive and discontinuous yielding behavior,namely serrated *** is observed that the stress-strain curves were dominated by type B serration,and original annealing twin boundaries(TBs)were distorted to various degrees under comparatively different lower tensile *** contrast,the TBs almost disappear,and the type B serrations become smoother and regular under the higher loading *** phenomenon can be attributed to the interactions between TBs and dislocations during tensile *** effects of the mobile and immobile dislocations illustrate the unsteady amplitude of serrations observed in stress-strain *** electron microscope images of tested pieces reveal the interaction of dislocation and TB,with dislocation tangling around the TBs.

关键词： Nickel-based superalloy Serrations Twin boundaries Deformation mechanism

Thioredoxin pathway regulated live-cell synthesis of CdSe quantum dots in Saccharomyces cerevisiae

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Science China Chemistry 2024年第11期67卷 3851-3860页

作者： Xu li Cai-Qin wu Jia-Wei Tu Juan Kong ling-ling Yang Zhi-Xiong Xie Dai-Wen Pang College of Chemistry and Molecular Sciences The Institute for Advanced Studies College of Life Sciences Wuhan University Research Center for Analytical Sciences College of Chemistry State Key Laboratory of Medicinal Chemical Biology Tianjin Key Laboratory of Biosensing and Molecular Recognition Frontiers Science Center for New Organic Matter Frontiers Science Center for Cell Responses and Haihe Laboratory of Sustainable Chemical Transformations Nankai University

Currently, the application of synthetic biology to artificially manipulate and utilize organisms for the synthesis of desired products such as nanomaterials with excellent fluorescence properties is attracting considerable attention. However, it is still difficult to obtain designed products efficiently due to insufficient knowledge of the biosynthetic mechanisms. The thioredoxin（TRX） and glutathione（GSH） pathways are generally conserved thiol-reductase systems that protect organisms from oxidative stress and are involved in selenium（Se） metabolism. In this study, we revealed the pivotal role of cytoplasmic TRX pathway in regulating the metabolism of Na2SeO3during the live-cell synthesis of cadmium-selenium quantum dots（Cd Se QDs） in Saccharomyces cerevisiae by regulating the expression level of genes related to TRX pathway and measuring the intracellular content of selenocysteine（Se Cys）. The determination of Se Cys metabolism in yeast with GSH pathway-related genes deleted demonstrated that the TRX pathway played a more significant role in Se Cys metabolism than GSH pathway. A 6.4-fold enhancement in the synthetic yield of Cd Se QDs was achieved through the overexpression of TRX pathway-related genes,improvement of synthetic procedure, and supplementation of GSH based on the understanding of biological *** the mechanism of CdSe QDs live-cell synthesis facilitates the precise manipulation of biological processes for the synthesis of inorganic nanomaterials.

关键词： thioredoxin glutathione quantum dot live-cell synthesis selenium metabolism Saccharomyces cerevisiae

Molding simulation of airfoil foam sandwich structure and interference optimization of foam-core

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Chinese Journal of Aeronautics 2024年第10期37卷 325-338页

作者： Qianying CEN Zeyang XING Qingyou WANG lili li Zhigang WANG Zhanjun wu ling liU School of Aerospace Engineering&Applied Mechanics Tongji UniversityShanghai 200092China AVIC Harbin Aircraft Industry Group Co.Ltd Harbin 150066China School of Aeronautics and Astronautics Dalian University of TechnologyDalian 116024China

During the Co-Cure Molding(CCM)of airfoil foam sandwich structure,it is challenging to avoid collapse of foam core at the trailing ***,an Equal Proportional Thickening(EPT)method is proposed to optimize the interference of polymethacrylimide(PMI)foam core during the CCM ***,based on some basic parameters of composite skin and foam core obtained by experiments or multi-scale simulations,a thermal-curing-mechanical coupling analysis for the CCM of foam sandwich structure is performed and the results show that the maximum stress within foam core occurs at the completion of mold-closing,which tends to decrease during the subsequent CCM ***,the foam core is thickened by traditional equidistant-thickening method,and the simulation reveals that the foam core at the trailing edge tends to collapse because of stress ***,if the foam core is thickened by the proposed EPT method,the mold-closing caused collapse at the trailing edge can be effectively avoided,and a thickening ratio range of 0.6%–2.0%is obtained,which is further proved by practical ***,the interference design scheme proposed can ensure the molding quality and effectively reduce the scrap of molded products.

关键词： Airfoil foam sandwich structure Polymethacrylimide(PMI)foam Interference Co-curing Molding simulation