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In vitro corrosion behavior of the extruded Mg–4Zn–1Mn alloy in different physiological solutions for biomedical applications

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Progress in Natural Science:Materials International 2023年第4期33卷 467-477页

作者： Yang Zheng He Tong jiawen Liu jia lu Weirong Li Fangfei Liu Ziyue Zhang Yan Li School of Aeronautics and Astronautics Tiangong University School of Mechanical Engineering Tiangong University Dongguan Eontec Co.Ltd. School of Materials Science and Engineering Beihang University

The extruded Mg–4Zn–1Mn alloy was prepared and its in vitro corrosion behavior in different physiological solutions of simulated body fluid(SBF), artificial saliva(AS) and artificial urine(AU) was investigated for biomedical applications. The microstructural characterization by optical microscope(OM), X-ray diffractometer(XRD), scanning electron microscopy(SEM) and energy dispersive X-ray spectrometer(EDS) showed that the alloy with an average grain size of approximate 20 μm was mainly composed of α-Mg matrix phase along with some MgZn2and α-Mn precipitates. The results of electrochemical corrosion and immersion corrosion tests revealed a distinct corrosion behavior for the alloy in different solutions with increasing immersion time. The corrosion morphologies were featured with flocculent precipitates in the SBF, flower-like clusters in the AS and columnar crystals in the AU. The alloy exhibited highest corrosion resistance and lowest corrosion rate in the AS compared with the SBF and the AU, which was attributed to the formation of a stable corrosion products layer.

关键词： Biodegradable metals Mg-4Zn-1Mn alloy Physiological solutions Corrosion behavior

Electroreduction of Benzoylformic Acid in 1-Ethyl-3-methylimidazolium Bromide Room Temperature Ionic Liquid

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Chemical Research in Chinese Universities 2005年第5期21卷 634-635页

作者： SUN Qian ZHAO Peng lu jia-xing HE Ming-yuan Shanghai Key Laboratory of Green Chemistry and Chemical Process Department of Chemistry East China Normal University Shanghai 200062 P. R. China

The chemical industry is under considerable pressure to replace many volatile organic compounds that are widely used as solvents in organic synthesis. This trend leads to the exploration for novel reaction media. Room temperature ionic liquids as environmentally benign media for organic synthesis and catalytic reactions have been gradually recognized and accepted Owing to their unique chemical and physical properties, ionic liquids become promising candidates as recyclable reaction media for “ Green” applications. These nonvolatile solvents have been used as media or catalysts in dozens of fields, such as organic synthesis, organometallic catalytic reactions, separation and extraction processes.

关键词： Ionic liquid Electroreduction Benzoylformic acid Cyclic vohammetry

Purification and Characterization of β-Glucosidase from a Newly Isolated Strain Tolypocladium cylindrosporum Syzx4

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Chemical Research in Chinese Universities 2011年第4期27卷 557-561页

作者： ZHANG Yi-bo YUAN Li-jia CHEN Zhao-jie FU lu lu jia-hui MENG Qing-fan HE Huan YU Xiao-xiao LIN Feng TENG Li-rong Key Laboratory for Molecular Enzymology ＆ Engineering Ministry of Education College of Life Science Jilin University Changchun 130012 P. R. China Department of Endocrinology Chian-Japan Union Hospital of Jilin University Changchun 130033 P. R. China

A higher β-glucosidase-producing strain was isolated and identified as Tolypocladium cylindrosporum syzx4 based on its morphology and internal transcribed spacer（ITS） rDNA gene *** present study is to ferment,purify and characterize a β-glucosidase from *** *** enzyme was purified to homogeneity by sulfate precipitataion,diethylaminoethyl cellulose anion exchange chromatography and Sephadex G-100 gel filtration with a 9.47-fold increase in specific activity and a recovery of 12.27%.The molecular weight（Mw） of the β-glucosidase was estimated to be 58600 by SDS-PAGE,which is much lower than that of the enzyme from other *** β-glucosidase shows high activity over a wide range of temperature from 35℃ to 70℃ and the optimum pH is approximately *** the kinetic parameters Km（0.85 mmol/L） and vmax[85.23 mmol/（L·s）] of the β-glucosidase were studied,respectively with high affinity p-nitrophenyl-β-D-glucopyranoside（p-NPG） as the substrate,inhibition constant Ki（39.5 mmol/L） with the tolerance of *** β-glucosidases have been purified and characterized from several other sources,*** β-glucosidase with the unique optimal pH and higher tolerance of glucose distinguished from others makes the β-glucosidase a potential application in simultaneous saccharification and fermentation（SSF）.

关键词： β-Glucosidase Purification Characterization Thermoacidophilic Tolypocladium cylindrosporum syzx4

Bending Failure Mode and Prediction Method of the Compressive Strain Capacity of A Submarine Pipeline with Dent Defects

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China Ocean Engineering 2024年第4期38卷 636-647页

作者： HOU Fu-heng jia lu-sheng CHEN Yan-fei ZHANG Qi ZHONG Rong-feng WANG Chun-sha School of Mechanical and Transportation Engineering China University of PetroleumBeijingBeijing 102249China CNOOC Research Institute Ltd.Beijing 100028 China

A dent is a common type of defects for submarine *** submarine pipelines,high hydrostatic pressure and internal pressure are the main *** pipelines bend due to complex subsea conditions,the compression strain capacity may be *** into the local buckling failure and accurate prediction of the compressive strain capacity are important.A finite element model of a pipeline with a dent is *** buckling failure under a bending moment is investigated,and the compressive strain capacity is *** effects of different parameters on pipeline local buckling are *** results show that the dent depth,external pressure and internal pressure lead to different local buckling failure modes of the pipeline.A higher internal pressure indicates a larger compressive strain capacity,and the opposite is true for external *** the ratio of external pressure to collapse pressure of intact pipeline is greater than 0.1,the deeper the dent,the greater the compressive strain capacity of the *** as the ratio is less than 0.1,the opposite is *** the basis of these results,a regression equation for predicting the compressive strain capacity of a dented submarine pipeline is proposed,which can be referred to during the integrity assessment of a submarine pipeline.

关键词： submarine pipeline dent defect bending load local buckling compressive strain capacity

Electrocarboxylation of Anthrone to Anthracene-9-carboxylic Acid in the Presence of CO_2

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Chemical Research in Chinese Universities 2011年第6期27卷 1027-1030页

作者： ZHANG Li WANG Huan ZHAO jian-qing CHEN Bao-li lu jia-xing Shanghai Key Laboratory of Green Chemistry and Chemical Process Department of Chemistry East China Normal University Shanghai 200062 P. R. China Advanced Analysis and Measurement Center Anhui University of Technology Ma＇anshan 243002 P. R. China

Electrocarboxylation of anthrone in the presence of CO2 to anthrance-9-carboxylic acid directly was carried out. The electroreduction behavior of anthrone was examined by cyclic voltammetry in the absence and presence of CO2. Then the influences of the supporting electrolytes, temperature, electrode material and anthrone concentration on the carboxylation yield were investigated. Under the optimized conditions, anthrancene-9-carboxylic acid was obtained in a good yield（96.1%）.

关键词： Anthracene-9-carboxylic acid Anthrone Carbon dioxide Electrocarboxylation

Simulation Analysis of Ammonia Leakage and Dispersion in a Large-Scale Refrigeration System

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Fluid Dynamics & Materials Processing 2022年第4期18卷 1049-1066页

作者： jianlu Cheng Kaiyong Hu jiang Shen lu jia Rui Niu Zhaoxian Yang Tianjin Key Laboratory of Refrigeration Technology Tianjin University of CommerceTianjin300134China International Trade Engineering Design Institute Beijing100037China Tianjin Tengsheng Technology Co. Ltd.Tianjin300380China

The use of ammonia in large-scale refrigeration systems(such as those used for a stadium)requires adequate ammonia leakage prevention mechanisms are put in *** the present study,numerical simulations have been conducted to study the dispersion law in the ammonia machinery room of the refrigeration system for the 2022 Beijing Winter *** wind speed,and release location have been varied to investigate their effects on the dispersion *** positions of the leakage points in the ammonia storage tank have been found to lead to different areas affected *** general,the dangerous region area decreases with an increase in the wind ***,when the wind is aligned with the leakage direction,this trend is *** study may offer an effective method to predict the impact of ammonia dispersion and implement the safe operation of such large-scale systems.

关键词： Numerical simulation ammonia diffusion leakage location ventilation

Rapid formation of metal-monophenolic networks on polymer membranes for oil/water separation and dye adsorption

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Chinese Chemical Letters 2021年第12期32卷 3852-3856页

作者： jia-lu Shen Bing-Pan Zhang Di Zhou Zhi-Kang Xu Ling-Shu Wan MOE Key Laboratory of Macromolecular Synthesis and Functionalization Key Laboratory of Adsorption and Separation Materials&Technologies of Zhejiang ProvinceDepartment of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

Surface deposition based on metal-phenolic networks(MPNs) has received increasing interest in recent years. The catechol structure is generally considered to be essential to the formation of MPNs. Our most recent results have demonstrated that some kinds of monophenols can form MPNs on substrate ***, we report a fast and effective surface-coating system based on the coordination of 3-(4-hydroxy-3-methoxyphenyl)-2-propenoic acid, a kind of monophenol, with Fe^(3+). Compared with other metal ions such as Cu^(2+)and Ni^(2+), Fe^(3+)with stronger electron acceptability can coordinate with the monophenol more strongly to form MPNs, and moreover, the deposition time significantly decreases to 40 min from generally 24 h. It is demonstrated that the deposition process is controlled by the coordination, Fe^(3+)hydrolysis, and deprotonation of the monophenol. The coatings endow substrates such as polypropylene microfiltration membrane with underwater superoleophobicity, which can be applied in oil/water separation with high separation efficiency and great long-term stability. In addition, the coated membranes are positively charged and thus are useful in selective adsorption of dyes. The present work not only provides a novel, fast, and one-step deposition method to fabricate MPNs, but also demonstrates that the fabrication efficiency of monophenol-based MPNs is comparable with that of polyphenol-based MPNs.

关键词： Metal-phenolic networks Polymer membrane Surface coating Oil/water separation Dye adsorption

Functional analysis of UG7207D3 associated with abamectin resistance in Tetranychus cinnabarinus(Boisduval)

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Insect Science 2020年第2期27卷 276-291页

作者： Meng-Yao Wang Xin-Yang Liu Li Shi jia-lu Liu Guang-Mao Shen Ping Zhang Wen-Cai lu Lin He Key Laboratory of Entomology and Pest Control Engineering College of Plant ProtectionSouthwest UniversityChongqingChina Academy o f Agricultural Sciences Southwest UniversityChongqingChina

Uridine diphosphate(UDP)-glycosyltransferases(UGTS)are widely distributed within living organisms and share roles in biotransformation of various lipophilic endo-and xenobiotics with activated UDP *** this study,it was found that the activity of UGTs in abamectin-resistant(AbR)strain was significantly higher(2.3-fod)than that in susceptible strain(SS)of Tetramychus *** analysis showed that 5-nitrouracil,the inhibitor ofUGTs,could enhance the lethal effect of abamectin on *** the previous microarray results,we found an UGT gene(UGT201D3)overexpressed in AbR *** PCR analysis showed that UGT20ID3 was highly expressed and more inducible with abamectin exposure in the AbR *** silencing the tran-scription of UGT201D3,the activity of UGTs was decreased and the susceptibility to abamectin was increased in AbR strain whereas it was not in ***,UGT201D3 gene was then succefully expressed in Escherichia *** recombinant UGT20ID3 exhibited a-naphthol activity(2.810.43 nmol mg protein/min),and the enzyme activity could be inhibited by abamectin(inhibitory concentration at 50%:57.50±3.54 μmol/L).High-performance liquid chromatography analysis demonstrated that the recombinant UGT201D3 could efctively deplete abamectin(15.77%±3.72%)incubating with 150 ug protein for 6 *** results provided direct evidence that UGT201D3 was involved in abamectin resistance in T cinnabarinus.

关键词： abamectin resistance prokaryotic expression RNA interference Tetrumychus cimnabarins UDP-glycosy ltransferases

Preparation of porous Si_(3)N_(4) ceramics via tailoring solid loading of Si_(3)N_(4) slurry and Si_(3)N_(4) poly‐hollow microsphere content

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Journal of Advanced Ceramics 2015年第4期4卷 260-266页

作者： jia-Min WU Xiao-Yan ZHANG Jie XU Ke GAN jia-lu LI Chen-Hui LI Jin-Long YANG Yu-Sheng SHI State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of New Ceramic and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

Porous Si_(3)N_(4) ceramics were prepared by aqueous gelcasting using Si_(3)N_(4) poly-hollow microspheres(PHMs)as pore-forming *** effects of solid loading of Si_(3)N_(4) slurry and Si_(3)N_(4) PHM content on the properties of porous Si_(3)N_(4) ceramics were ***β-Si_(3)N_(4) phase is observed in porous Si_(3)N_(4) ceramics,and Si_(3)N_(4) PHMs distribute uniformly both in Si_(3)N_(4) green samples and porous Si_(3)N_(4) *** show that solid loading of Si_(3)N_(4) slurry and Si_(3)N_(4) PHM content could considerably influence the properties of porous Si_(3)N_(4) *** the increase of solid loading of Si_(3)N_(4) slurry(decrease of Si_(3)N_(4) PHM content),the distributing state of Si_(3)N_(4) PHMs changes from contacting with each other to just embedding in the matrix,thus their porosity decreases,while their shrinkage,flexural strength,and fracture toughness increase.

关键词： porous Si_(3)N_(4)ceramics Si_(3)N_(4)poly-hollow microspheres(PHMs) solid loading aqueous gelcasting mechanical properties