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Inhomogeneous Deformation of Multilayered Roll-Bonded Brass/Cu Composites

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Acta Metallurgica Sinica(English Letters) 2015年第5期28卷 600-607页

作者： Nan Jia Ming-Wei Zhu yi-Ran Zheng Tong he xiang Zhao Key Laboratory for Anisotropy and Texture of Materials (ATM) Northeastern University Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Research Institute Northeastern University

The deformation gradients in multilayered hot roll-bonded composite materials incorporating two dissimilar face-centered cubic metals, i.e., brass and Cu, were investigated by characterizing the deformation microstructure, hardness and texture at different thickness positions of the composites. For the constitutive metals, the center part of each metal sheet forms the substructure containing coarse grains, while the ultrafine grains and significant shear banding form in the outer part. As deformation increases, the cross-interface shear occurs in the Cu sheet of the composites. Then, grain fragmentation, shear banding and dynamic recovery become the main factors that influence hardness of the metal. Moreover, in the co-deformed composites, the interface between brass and Cu plays a role in texture developments of the individual metals.

关键词： Deformation Multilayers Brass/Cu composites Texture

Antiproliferative piperidine alkaloids from giant taro(Alocasia macrorrhiza)

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Chinese Journal of Natural Medicines 2022年第7期20卷 541-550页

作者： GAO Wei WANG yi WANG Ru WANG yi-Hai XU Jing-Wen he xiang-Jiu School of Pharmacy Guangdong Pharmaceutical UniversityGuangzhou 510006China Guangdong Engineering Research Center for Lead Compounds&Drug Discovery Guangzhou 510006China

The rhizome of giant taro(Alocasia macrorrhiza(L.)Schott),which is a highly adaptable wild plant,is a traditional Chinese herbal *** the current study,the antiproliferative constituents of giant taro were investigated and six new(1−6)and four known piperidine alkaloids(7−10)were isolated from its *** chemical structures and absolute configurations were elucidated using various spectroscopic methods and the Mosher ester *** isolated alkaloids were screened for the antiproliferative activity through MTT *** results indicated that piperidine alkaloids exerted potential antiproliferative activity against hepG2,AGS and MCF-7 tumor *** researches showed that compounds 3−5 dose-dependently decreased the colony formation rate and induced the apoptosis of AGS cells,while compound 4 induced AGS cell death via the proapoptotic *** study demonstrates that the piperidine alkaloids isolated from giant taro exhibit significant antitumor activity,which provides phytochemical evidence for further development and utilization.

关键词： Giant taro Alocasia macrorrhiza Piperidine alkaloids Antiproliferative Apoptosis

High durable aqueous zinc ion batteries by synergistic effect of V_(6)O_(13)/VO_(2) electrode materials

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Journal of Energy Chemistry 2023年第12期87卷 334-341,I0009页

作者： yi Liu xiang Wu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870LiaoningChina

Vanadium oxides have attracted one’s wide attention due to their diverse valences and spatial structure as cathode for aqueous zinc ion ***,a strong electrostatic interaction exists between Zn ions and host materials,which leads to their sluggish reaction kinetics and inferior structural ***,we design a kind of vanadium-based electrode materials with abundant phase boundaries and oxygen *** assembled Zn//V_(6)O_(13)/VO_(2) batteries deliver a specific capacity of 498.3 mA h g^(-1)at 0.2 A g^(-1) and retain a capacity of 485.8 mA h g^(-1)after 100 ***,they achieve a retention rate of 96.8% after 5000 cycles at 10 A g^(-1).The soft pack cells also show excellent mechanical stability at different folding conditions.

关键词： Aqueous zinc ion batteries Vanadium oxide Cathode material Phase boundary Cycling stability

Asymmetric reduction of α-hydroxy aromatic ketones to chiral aryl vicinal diols using carrot enzymes system

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Chinese Chemical Letters 2012年第6期23卷 635-638页

作者： xiang Liu yi Wang Hai Yan Gao Jian he Xu a School of Chemical and Material Engineering Jiangnan University Wuxi 214122 China State Key Laboratory of Bioreactor Engineering East China University of Science and Technology Shanghai 200237 China

Asymmetric reduction of ct-hydroxy aromatic ketones was carded out by using carrot enzymes system, yielding corresponding chiral vicinal diols with special functional groups. The optimum reaction conditions were obtained after investigation of various influencing factors. Chiral aryl vicinal diols were produced with good yields and excellent enantiomeric excesses under appropriate conditions. Meanwhile, the steric factors and electronic effects of the substituents on the aromatic ring were shown to have an interesting influence on both yield and enantioselectivity.

关键词： Asymmetric reduction Chiral aryl vicinal diol Aromatic ketone Carrot cell

Towards High Molecular Weight Poly(bisphenol A carbonate) with Excellent Thermal Stability and Mechanical Properties by Solid-State Polymerization

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Chinese Journal of Polymer Science 2015年第8期33卷 1176-1185页

作者： Yu-ling he yi-lan Guo Rui he Tian-xiang Jin 陈枫傅强 Nan Zhou Ji Shen College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan University China Bluestar Chengrand Chemical Co. Ltd.

Poly（bisphenol A carbonate）（BPA-PC） was post-polymerized by solid-state polymerization （SSP） after supercritical CO2-induced crystallization in low molecular weight particles prepolymerized via melt transesterification reaction. The effects of the crystallization conditions on melting behavior and SSP of BPA-PC were investigated with differential scanning calorimetry （DSC）, Ubbelohde viscosity method and gel permeation chromatography （GPC）. The reaction kinetics of the SSP of crystallized prepolymers was studied as a function of reaction temperatures for various reaction periods. As a result, the viscosity average molecular weight of BPA-PC particles （2 mm） increased from 1.9 × 10^4 g/mol to 2.8 × 10^4 g/mol after SSP. More importantly, the significantly enhanced thermal stability and mechanical properties of solid-state polymerized BPA-PC, compared with those of melt transesterification polymerized BPA-PC with the same molecular weight, can be ascribed to the substantial avoidance of undergoing high temperature during polymerization. Our work provides a useful method to obtain practical product of BPA-PC with high quality and high molecular weight.

关键词： Poly(bisphenol A carbonate) Solid-state polymerization Supercritical C02-induced crystallization Highmolecular weight High quality.

洞庭湖区三个村日本血吸虫病的发病与感染及其有关因素的分析

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中国血吸虫病防治杂志 1992年第5期4卷 260-263页

作者：余冬保李岳生李毅向阳何永康湖南省寄生虫病防治研究所岳阳414000

调查洞庭湖区1个农业村和2个渔业村的经济状况,以渔业村较好,但居民血吸虫病感染率及感染度也高,其中以从事捕捞业的渔业村为最高,这与该村居民接触疫水的强度和频度有关;居民对血吸虫病的认识和对基本防护知识的掌握程度与感染的发生有... 详细信息

调查洞庭湖区1个农业村和2个渔业村的经济状况,以渔业村较好,但居民血吸虫病感染率及感染度也高,其中以从事捕捞业的渔业村为最高,这与该村居民接触疫水的强度和频度有关;居民对血吸虫病的认识和对基本防护知识的掌握程度与感染的发生有关,了解程度较差的人群感染率较高;血吸虫病症状及体征的出现亦与血吸虫感染的发生和强度有关。

关键词：日本血吸虫病感染发病

Study on Load Bearing Characteristics of Novel Expandable Deepwater Drilling Conductor Based on Laboratory Experiment and Field Test

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China Ocean Engineering 2023年第1期37卷 16-28页

作者： ZHANG Ming-he YANG Jin YANG Yu-xiang XU Dong-sheng ZHOU yi-su College of Safety and Ocean Engineering China University of Petroleum-BeijingBeijing 102249China

A novel expandable conductor was designed and applied in deep-water drilling to improve the vertical and lateral bearing capacity with a significant reduction of conductor jetting depth and soaking time. The vertical and lateral bearing capability of expandable conductors was depicted based on the ultimate subgrade reaction method and pile foundation bearing theory. The load-bearing characteristics of a laboratory-scale expandable conductor were analyzed through laboratory experiments. The serial simulation experiments are accomplished to study the bearing characteristics(vertical ultimate bearing capacity, lateral soil pressure, and lateral displacement) during the conductor soaking process. The laboratory experimental results show that the larger the length and thickness of expandable materials are,the higher the bearing capacity of the wellhead will be. During the conductor soaking process, the soil pressure around the three expandable conductors increases faster, strings representing a stronger squeezing effect and resulting in higher vertical bearing capacity. Furthermore, the lateral displacement of novel expandable conductor is smaller than that of the conventional conductor. All the advantages mentioned above contributed to the reduction of conductor’s jetting depth and soaking time. Lastly, the application workflow of a novel expandable deep-water drilling conductor was established and the autonomous expandable conductor was successfully applied in the South China Sea with a significant reduction of conductor’s jetting depth and soaking time. According to the soil properties and designed installation depth of the surface conductor, the arrangement of expandable materials should be designed reasonably to meet the safety condition and reduce the construction cost of the subsea wellhead.

关键词： novel expandable surface conductor deep water subsea wellhead laboratory experiment field test

First finding of continental deep subduction in the Sesia Zone of the Western Alps and implications for subduction dynamics

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National Science Review 2023年第5期10卷 154-166页

作者： yi-xiang Chen Kun Zhou Qiang he Yong-Fei Zheng Hans-Peter Schertl Kun Chen CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of China Center of Excellence for Comparative Planetology Chinese Academy of Sciences Institute of Geology Mineralogy and Geophysics Faculty of GeosciencesRuhr University Bochum

Continental deep subduction after the closure of large oceanic basins is commonly ascribed to the gravitational pull of the subducting oceanic ***,it is not clear how continental lithosphere adjacent to small oceanic basins was subducted to mantle *** Sesia Zone in the Western Alps provides an excellent target for exploration of subduction dynamics in such a tectonic *** we report the first finding of coesite in a jadeite-bearing orthogneiss from the Sesia Zone,providing the first evidence for deep subduction of the continental crust to mantle depths for ultrahigh-pressure(UHP)metamorphism in this *** coesite inclusions were identified by laser Raman spectroscopy in two garnet *** on zircon U-Pb dating and trace element analysis, the UHP metamorphic age was constrained to be 76.0 ±1.0 *** phase equilibrium modeling yields peak metamorphic pressures of2.8-3.3 GPa,demonstrating the continental deep subduction to mantle depths of>80 *** subducted continental crust was a rifted hyperextended continental margin,which was converted to the passive continental margin during seafloor spreading and then deeply subducted during the oblique convergence between the Adria microplate and Eurasian plate in the Late *** the slab pull could only play a limited role in closing small oceanic basins for continental collision,the distal push of either continental breakup or seafloor spreading is suggested as the major driving force for the deep subduction of continental crust in the Western ***,deep subduction of the continental crust bordering small oceanic basins would have been induced by the far-field stress of compression,whereas that bordering large oceanic basins was spontaneous due to the oceanic slab *** provides a new insight into the geodynamic me chanism of continental deep subduction.

关键词： coesite ultrahigh-pressure metamorphism continental deep subduction Western Alps far-field stress

Cretaceous basin evolution in northeast Asia:tectonic responses to the paleo-Pacific plate subduction

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National Science Review 2022年第1期9卷 144-161页

作者： Qing-Ren Meng Zhong-he Zhou Ri-xiang Zhu yi-Gang Xu Zheng-Tang Guo State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Innovation Academy for Earth Science Chinese Academy of Sciences College of Earth and Planetary Sciences University of Chinese Academy of Sciences Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Key Laboratory of Cenozoic Geology and Environment Chinese Academy of Sciences

Cretaceous rift basin evolution was an important part of the tectonic history of northeast Asia in the late *** types of rift basins are identified—active,passive and wide rift basins—and they developed in different *** rift basins in the eastern North China craton are thought to be the consequence of crustal stretching and passive asthenospheric *** rift basins in the eastern Central Asian orogen are assumed to originate from gravitational collapse of the thickened and heated orogenic *** rift basins in the northern North China craton are attributed to uprising of asthenospheric materials along a lithospheric-scale tear *** tearing of the sub ducting paleo-Pacific plate is postulated and well explains the spatial distribution of different types of rift basins and the eastward shifting of magmatism in the northern North China *** Late Cretaceous witnessed a period of mild deformation and weak magmatism,which was possibly due to kinematic variation of the paleo-Pacific plate.

关键词： NE Asia Cretaceous rift basin volcanism paleo-Pacific plate