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Chinese Journal of Polymer Science 2021年第5期39卷 610-619,I0007页

作者： peng huo Cheng-Tang Zhong Xiao-peng Xiong Department of Materials Science and Engineering College of MaterialsXiamen UniversityXiamen 361005China

Poly(vinylidene fluoride-co-hexafluoropropylene)(PVDF-HFP)receives increasing attention in membrane separation field based on its advantages such as high mechanical strength,thermal and chemical ***,controlling the microporous structure is still *** this work,we attempted to tailor the morphology of PVDF-HFP membrane via a one-step reactive vapor induced phase separation ***,PVDF-HFP was dissolved in a volatile solvent and then was cast in an ammonia water vapor *** complete evaporation of solvent,membranes with adjustable porous structure were prepared,and the microstructures of the membranes were analyzed by scanning electron microscopy,Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy and X-ray diffraction *** on the results,a mechanism of dehydrofluorination induced cross-linking of PVDF-HFP has been suggested to understand the morphology *** our knowledge,this is the first report of one-step reactive vapor induced phase separation strategy to tailor morphology of PVDF-HFP *** addition,the membranes prepared in the ammonia water vapor exhibited enhanced mechanical strength and achieved satisfactory separation efficiency for water-in-oil emulsions,suggesting promising potential.

关键词： PVDF-HFP Membrane Tailoring Vapor induced phase separation Oil-water separation

Mechanism of plasticity enhancement of AZ31B magnesium alloy sheet by accumulative alternating back extrusion

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Journal of Magnesium and Alloys 2023年第5期11卷 1791-1801页

作者： Ye Wang Feng Li Nan Bian Hua Qiu Du peng Da huo School of Materials Science and Engineering Harbin University of Science and TechnologyHarbin 150040PR China Key Laboratory of Advanced Manufacturing and Intelligent Technology Ministry of EducationHarbin University of Science and TechnologyHarbin 150080PR China

Accumulative alternating back extrusion was a potential fine-grain modification *** this paper,it was an innovative attempt to develop high-performance magnesium alloy sheet by this *** the condition of 350 K,commercial AZ31 magnesium alloy was made into billet by accumulative alternating back extrusion,and then extruded into fine-grain magnesium alloy *** a systematic study of its microstructure and mechanical properties,the results showed that the initial state had an important influence on the evolution of the structure during *** accumulative alternating back extrusion to produce the billet,the grain size of the sheet obtained by extrusion was significantly refined,which was related to the accumulation of deformation and grain refinement during the alternating loading *** refinement caused the proportion of dynamic recrystallization inside the sheet with 2 cycles of accumulative alternating back extrusion to drop to 27%.With the increase of extrusion cycles from 2 to 4,the high density of dislocations led to an increase in the proportion of dynamic recrystallization and finer *** texture changed from strong basal texture to weak bimodal *** results of uniaxial tensile test show that due to grain refinement and texture change,the yield strength was significantly reduced,and the plasticity was significantly *** was verified that accumulative alternating back extrusion was meaningful for subsequent processing,and it also provided scientific guidance for the development of fine-grained magnesium alloy sheet.

关键词： Magnesium alloy Alternating back extrusion Microstructure uniformity Bimodal texture Texture weakening Sheet anisotropy

Microstructure Characteristics and Corrugation Interface Behavior of Al/Mg/Al Composite Plate Rolled Under Large Strain

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Acta Metallurgica Sinica(English Letters) 2023年第5期36卷 827-838页

作者： peng-Da huo Feng Li Wen-Tao Niu Rong-He Gao&An-Xin Zhang School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin150040China Key Laboratory of Micro-systems and Micro-structures Manufacturing of Ministry of Education Harbin Institute of TechnologyHarbin150001China Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationHarbin Engineering UniversityHarbin150001China

Traditional rolled(TR)aluminum(Al)/magnesium(Mg)/aluminum(Al)composite plates have many bottlenecks such as multiple passes,low interlaminar strength,and weak mechanical *** this paper,the hard-plate rolling(HPR)method was used to prepare Al/Mg/Al composite plates under a single pass reduction of 60%.The results show that the ultimate tensile strength(UTS)of the composite plate obtained by hard-plate rolling is 262.3 MPa,and the percentage of total elongation at fracture(At)is 12.3%,which is 31.6%and 37.4%higher than that of the traditional rolling,*** is attributed to the unique corrugated interlocking structure of the interface of the composite plate caused by hard-plate *** shear texture produced by the Mg plate weakens the strong-basal *** the same time,the strong basal slip and the large amount of energy stored in the deformed grains provide favorable conditions for dynamic recrystallized(DRX)*** microstructure is deeply refined by DRX,and the strength and plasticity of the composite plate are improved *** provides scientific guidance for the development of high-performance lightweight composite plates and the research on hard-plate rolling technology and also has good industrial production and application potential.

关键词： Hard-plate rolling Al/Mg/Al composite plate Corrugated interface Strength-plasticity Strengthening mechanism

Synthesis and Optical Properties of Hyperbranched PAEKs Containing Porphyrin and Its Metal Derivatives

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Chinese Journal of Polymer Science 2014年第1期32卷 73-83页

作者： Xu Jiang Yin-long Du Chuan Liu peng-fei huo Zhi Geng Shu-ling Zhang 王贵宾 College of Chemistry Engineering Research Center of High Performance Plastics Ministry of Education Jilin University

Novel functional hyperbranched poly（aryl ether ketone）s （HPAEKs） bonded with nonlinear optical chromophores （meso-tetrakis（4-hydroxyphenyl） porphyrin, THPP and its metal derivatives） were synthesized and characterized by IH-NMR and UV-Vis absorption spectra. The incorporation of chromophores into HPAEKs endowed HPAEKs novel NLO and OL properties. Indeed, dendritic architecture allowed for maximum dispersion of the chromophores, avoided aggregation, more optical limiting property was obtained. Simultaneously, they retained the excellent properties of the materials, particularly in thermal stability. Their optical properties were evaluated by nonlinear optical analyses and optical limiting. The results showed that these polymers possessed good optical limiting （OL） property and large nonlinear optical （NLO） susceptibilities （ca. 10-12 esu）. All polymers containing chromophores presented excellent thermal stability （DT5 〉 524.17 ℃）.

关键词： Porphyrin Poly(aryl ether ketone)s Hyperbranched Optical limiting.

Synthesis of new 2-aryl-6-styryl-2,3-dihydropyridin-4(1H)-one derivatives from curcuminoids

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Chinese Chemical Letters 2009年第11期20卷 1291-1295页

作者： Ying peng huo Xu Qiu Wei Yan Shao Lin Kun An Xian Zhang Bu Lian Quan Gu School of Pharmaceutical Sciences Sun Yat-Sen University Guangzhou 51006 China

Series of new 2-aryl-6-styry1-2,3-dihydropyridin-4（1H）-one derivatives were synthesized in acceptable to good yields by treatment of the curcuminoids with aqueous ammonia, the mechanism was proposed. By modification of the primary products, total 13 new compounds were obtained. The structures of all products were elucidated by spectroscopy analysis including HR-MS, 1H NMR and ^13C NMR.

关键词： Dihydropyridinone Curcumin Aqueous ammonia

Insights into reactive oxygen species formation induced by water-soluble organic compounds and transition metals using spectroscopic method

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Journal of Environmental Sciences 2023年第2期124卷 835-845页

作者： Tianyi Zhao Yu Yan Bian Zhou Xuezhen Zhong Xiaoyu Hu Lijia Zhang peng huo Kang Xiao Yuanxun Zhang Yang Zhang College of Resources and Environment University of Chinese Academy of SciencesBeijing 101408China Resource and Environmental Branch China National Institute of StandardizationHaidian DistrictBeijing 100191China Beijing Yanshan Earth Critical Zone National Research Station Chinese Academy of SciencesBeijing 101400China National Engineering Laboratory for VOCs Pollution Control Material&Technology University of Chinese Academy of SciencesBeijing 101400China

Ambient particulate matter(PM)can cause adverse health effects via their ability to produce Reactive Oxygen Species(ROS).Water-Soluble Organic Compounds(WSOCs),a complex mixture of organic compounds which usually coexist with Transition Metals(TMs)in PM,have been found to contribute to ROS ***,the interaction between WSOCs and TMs and its effect on ROS generation are still *** this study,we examined the ROS concentrations of V,Zn,Suwannee River Fulvic Acid(SRFA),Suwannee River Humic Acid(SRHA)and the mixtures of V/Zn and SRFA/SRHA by using a cell-free 2’,7’-Dichlorodihydrofluorescein(DCFH)*** results showed that V or Zn synergistically promoted ROS generated by SRFA,but had an antagonistic effect on ROS generated by *** quenching experiments indicated that V and Zn were more prone to form stable complexes with aromatic humic acid-like component(C1)and fulvic acidlike component(C3)in SRFA and *** suggested that the underlying mechanism involving the fulvic acid-like component in SRFA more tending to complex with TMs to facilitate ROS generation throughπelectron *** work showed that the complexing ability and complexing stability of atmospheric PM organics with metals could significantly affect ROS *** is recommended that the research deploying multiple analytical methods to quantify the impact of PM components on public health and environment is needed in the future.

关键词： Water-soluble organic carbons Transition metals Reactive oxygen species Excitation-emission matrix

知识密集型服务业空间集聚的动态演化及驱动因素

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长江流域资源与环境 2022年第4期31卷 770-780页

作者：霍鹏郑州师范学院社会服务与发展学院河南郑州450044 河南大学商学院河南开封475004

知识密集型服务业是我国构建现代自主创新体系的重要组成部分。通过构建集聚综合测度模型,探索了我国地级及以上城市知识密集型服务业空间集聚的动态演化趋势,采用地理加权回归模型揭示了知识密集型服务业空间集聚的驱动因素。研究发现:... 详细信息

知识密集型服务业是我国构建现代自主创新体系的重要组成部分。通过构建集聚综合测度模型,探索了我国地级及以上城市知识密集型服务业空间集聚的动态演化趋势,采用地理加权回归模型揭示了知识密集型服务业空间集聚的驱动因素。研究发现:(1)我国知识密集型服务业总体集聚程度较低,行业集聚不充分,地区集聚不均衡,各细分行业集聚态势差异明显,空间集聚逐渐向以东部沿海地区为中心,中、西部地区为外围的趋势发展;(2)知识密集型服务业集聚存在明显的空间正自相关性,邻近地区知识密集型服务业集聚具有较强相互带动作用;(3)城市化水平、研发强度、制度环境因素、知识存量总体上是驱动知识密集型服务业空间集聚的重要力量,基于空间异质性的分析,知识密集型服务业空间集聚驱动因素对不同地区影响差异较大,总体上呈现明显的阶梯分布特征,相邻省会或直辖市变量弹性系数空间上呈显著的连片分布特征,集聚驱动因素空间外溢效应明显。

关键词：知识密集型服务业集聚动态演化空间相关

Core and variable antimicrobial resistance genes in the gut microbiomes of Chinese and European pigs

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Zoological Research 2024年第1期45卷 189-200页

作者： Cui-Hong Tong Zhi-peng huo Lu Diao Dan-Yu Xiao Ruo-Nan Zhao Zhen-Ling Zeng Wen-Guang Xiong Guangdong Provincial Key Laboratory of Veterinary Pharmaceutics Development and Safety Evaluation South China Agricultural UniversityGuangzhouGuangdong 510642China National Risk Assessment Laboratory for Antimicrobial Resistance of Animal Original Bacteria College of Veterinary MedicineSouth China Agricultural UniversityGuangzhouGuangdong 510642China National Laboratory of Safety Evaluation(Environmental Assessment)of Veterinary Drugs South China Agricultural UniversityGuangzhouGuangdong 510642China National Reference Laboratory of Veterinary Drug Residues South China Agricultural UniversityGuangzhouGuangdong 510642China

Monitoring the prevalence of antimicrobial resistance genes(ARGs)is vital for addressing the global crisis of antibiotic-resistant bacterial *** its importance,the characterization of ARGs and microbiome structures,as well as the identification of indicators for routine ARG monitoring in pig farms,are still lacking,particularly concerning variations in antimicrobial exposure in different countries or ***,metagenomics and random forest machine learning were used to elucidate the ARG profiles,microbiome structures,and ARG contamination indicators in pig manure under different antimicrobial pressures between China and *** showed that Chinese pigs exposed to high-level antimicrobials exhibited higher total and plasmid-mediated ARG abundances compared to those in European pigs(P<0.05).ANT(6)-Ib,APH(3')-IIIa,and tet(40)were identified as shared core ARGs between the two pig ***,the core ARGs identified in pig populations were correlated with those found in human populations within the same geographical *** and Prevotella were identified as the dominant genera in the core microbiomes of Chinese and European pigs,*** ARG markers and 43 biomarkers were able to differentiate between the Chinese and European pig manure samples with accuracies of 100%and 98.7%,*** for assessing ARG contamination in Chinese and European pigs also achieved high accuracy(r=0.72-0.88).Escherichia flexneri in both Chinese and European pig populations carried between 21 and 37 *** results of this study emphasize the importance of global collaboration in reducing antimicrobial resistance risk and provide validated indicators for evaluating the risk of ARG contamination in pig farms.

关键词： Metagenomic Pig manure Antimicrobial pressure Antimicrobial resistance genes Microbiome

Method for identifying effective carbonate source rocks:a case study from Middle-Upper Ordovician in Tarim Basin,China

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Petroleum Science 2020年第6期17卷 1491-1511页

作者： Jun-Qing Chen Xiong-Qi Pang Song Wu Zhuo-Heng Chen Mei-Ling Hu Luo-Fu Liu Kui-You Ma Bo Pang Zhi-peng huo State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of PetroleumBeijing 102249China College of Geoscience China University of PetroleumBeijing 102249China Geological Survey of Canada CalgaryAB T2L 2A7Canada Research Institute of Petroleum Exploration and Development PetroChina Huabei Oilfi eld CompanyRenqiu 062550HebeiChina China University of Geosciences Beijing 100083China

Hydrocarbon expulsion occurs only when pore fluid pressure due to hydrocarbon generation in source rock exceeds the force against migration in the adjacent carrier *** the Middle-Upper Ordovician carbonate source rock of Tarim Basin in China as an example,this paper proposes a method that identifies effective carbonate source rock based on the principles of mass *** from the Well YW2 indicate that the Middle Ordovician Yijianfang Formation contains effective carbonate source rocks with low present-day *** and geochemical analysis suggests that the hydrocarbons in the carbonate interval are likely self-generated and *** steranes from GC-MS analysis of oil extracts in this interval display similar features to those of the crude oil samples in Tabei area,indicating that the crude oil probably was migrated from the effective source *** applying to other wells in the basin,the identified effective carbonate source rocks and non-source rock carbonates can be effectively identified and consistent with the actual exploration results,validating the *** the contribution from the identified effective source rocks with low present-day TOC(TOC_(pd))is considered,the long-standing puzzle between the proved 3 P oil reserves and estimated resources in the basin can be reasonably explained.

关键词： Effective carbonate source rock Mass balance approach Low present-day TOC Ordovician Tarim Basin

Microstructure evolution and ductility improvement mechanisms of magnesium alloy in interactive alternating forward extrusion

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Transactions of Nonferrous Metals Society of China 2022年第8期32卷 2557-2568页

作者： Hua-qiu DU Feng LI peng-da huo Yu WANG School of Materials Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150040China Key Laboratory of Advanced Manufacturing and Intelligent Technology Ministry of EducationHarbin University of Science and TechnologyHarbin 150080China

The microstructural evolution and mechanical properties of AZ31 magnesium alloy processed by the interactive alternating forward extrusion at different loading displacements(h=3,6,9 mm)were *** microscopy(OM)and electron backscatter diffraction(EBSD)were used to analyze the evolution of microstructure,and the mechanical behavior was clarified by tensile tests and scanning electron microscopy(SEM).The results show that continuous dynamic recrystallization(CDRX)and discontinuous dynamic recrystallization(DDRX)can achieve grain refinement jointly in interactive alternating forward *** the decrease of the loading displacement h,the proportion of recrystallization increases from 23.4%to 66.7%.The fiber texture gradually tilts to the extrusion direction(ED),and the grain orientation randomization of DDRX further weakens the fiber texture *** h=3 mm,the ultimate tensile strength(UTS)is 249.1 MPa and the elongation can reach 29.4%.

关键词： magnesium alloy alternating extrusion grain refinement texture weakening