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Chinese Chemical Letters 1998年第2期9卷 149-150页

作者： Li, WS Shen, ZQ zhang, yf Zhejiang Univ Dept Polymer Sci & Engn Hangzhou 310027 Peoples R China

The Ziegler-Natta type catalytic systems composed of lanthanide compound and ethyl aluminum sesquichloride are effective to convert chloromethyl thiirane to polymer of molecular weight ca. 10,000. The effects of rare ... 详细信息

关键词： chloromethyl thiirane ring-opening polymerization rare earth catalyst

Simulation of Stable Crack Growth for Welded Joints Including Strength Mismatching

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Journal of Materials Science & Technology 1999年第6期15卷 567-570页

作者： Jing, HY Luo, LX zhang, yf Minami, F Tianjin Univ Coll Mat Sci & Engn Tianjin 300072 Peoples R China Osaka Univ Osaka Japan

A 3-D computational method to simulate stable growth of a macroscopic crack under model condition is described in this paper. The Gurson-Tvergaard plasticity model for voided materials describes the damage process. Fixed-sized, computational cell elements (containing voids) defined over a thin layer at the crack plane simulate the ductile crack extension. Outside of this layer, the material remains undamaged by the void growth, follows the conventional J2 flow theory. The micromechanics parameters controlling crack growth are D, the thickness of computational cell layer and f(0), the initial void porosity. Calibration of these parameters proceeds through analyses of ductile tearing to match R-curve obtained from testing of deep notch bend specimens for welded joints. The effect of the strength mismatching on ductile crack growth for welded joints is simulated also.

关键词： Joints (structural components)

Study on Coastal Protection Engineering in the Area of Abandoned Yellow River Mouth

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China Ocean Engineering 1998年第2期13卷 223-234页

作者： zhang, yf Yu, GH Sheng, ZC Xu, M Nanjing Hydraul Res Inst River & Harbour Dept Nanjing 210024 Peoples R China

This paper reviews the history of coast evolution and coastal protection in the area of the abandoned Yellow River mouth in Jiangsu Province, analyzes the erosion characteristics and dynamic environment, evaluates the efficiency of coastal protection engineering works and designs the dimensions of the main seadike and offshore submerged dam. A gerneral scheme of shore protection for this area is proposed.

关键词： coastal protection coastal erosion wave calculation main seadike groin offshore submerged dam

PREFERENTIAL SEPARATION OF ALCOHOL FROM AQUEOUS SOLUTION THROUGH HYDROPHILIC MEMBRANES－POLY（ETHYLENEOXIDE）（PEO）／CHITOSAN（CS） BLEND MEMBRANE

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Chinese Chemical Letters 1995年第6期6卷 543-544页

作者： Wang, XP zhang, FY Shen, ZQ zhang, yf Lin, RX Zhejiang Univ Dept Polymer Sci & Engn Hangzhou 310027 Peoples R China Zhejiang Univ Dept Chem Hangzhou 310027 Peoples R China

the pervaporation behaviours of aqueous ethanol mixtures though the Poly(etbylene oxide)(PEO)/Chitosan(CS)blend seborane have been *** results show that both CS and PEO/CS membranes preferentially permeate ethanol at lower ethanol concentration in feed, and the selectivity of chitosan membrane toward alcohol can be greatly improved by introducing weter-soluble polymer PEO into chitosan.

关键词： PEO CHITOSAN ETHYLENEOXIDE POLY BLEND ALCOHOL AQUEOUS CS

STUDIES OF SUPERSONIC BASE FLOWS WITH COMPRESSIBLE RANS/LES METHODS

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STUDIES OF SUPERSONIC BASE FLOWS WITH COMPRESSIBLE RANS/LES ...

庆祝中国力学学会成立50周年暨中国力学学会学术大会’2007

作者： XIAO ZX HUANG JB zhang yf LI QB CHEN HX FU S~(1)) (School of Aerospace Engineering,Tsinghua University,Beijing 100084,China)

For the supersonic air vehicles,the base drag could be amount to 30%～40%of the total *** in the base drag is highly desirable to achieve the overall drag reduction and longer flight *** base drag reduction control methods generally contain two typical forms,*** active and passive *** control methods can reduce the base drag by increasing the base pressure,even achieve thrust,but they need additional devices and complex control *** modifications of base geometry can be considered as effectively passive drag reduction methods which do not alter base structures and induce little additional skin friction drag.

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阳光下步行获益更多(译文)

中华高血压杂志 2021年第6期29卷 596-597页

作者：刘瑾(译) 练桂丽(审校) zhang R Chen H Liu YX zhang WH Lu Q Yamanishi H Yamanishi C Yamanishi K Qiu YL Ye XF Huang ZR zhang BY Chen yf Zheng YQ zhang yf Guo ZZ Dong D Liu TX Dai YQ Xu MH Hao Y Li SZ Cai FY Wang RQ Guo XY Zhu DH zhang HY Zeng ZT Higashino H 机构不详

我刊2018年第10期刊登了一篇上海交通大学医学院陈红教授团队的研究《缓步行走3km对血压心率的影响及其辅助降压的β-内啡肽机制》,发现缓步行走3km可降低正常血压者及高血压患者的血压。后来作者又发现阳光下与非阳光条件下的步行存在... 详细信息

我刊2018年第10期刊登了一篇上海交通大学医学院陈红教授团队的研究《缓步行走3km对血压心率的影响及其辅助降压的β-内啡肽机制》,发现缓步行走3km可降低正常血压者及高血压患者的血压。后来作者又发现阳光下与非阳光条件下的步行存在差别,因此进一步设计了对比阳光下与非阳光步行降压效果与机制的研究。根据初步研究结果,作者于2019年在《中国药理学报(英文版)》"Correspondence(通信)"栏目中刊登了"Sunny walking counts more"一文,经作者推荐和《中国药理学报(英文版)》编辑部同意,我刊将其翻译为中文版本,以飨读者。

关键词：中国药理学报中文版本正常血压血压心率上海交通大学医学院阳光步行

Diatomic Pd catalyst with conjugated backbone for synergistic electrochemical CO_(2)reduction

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Nano Research 2024年第6期17卷 4850-4855页

作者： Wenxuan zhang Mengran zhang Hongjuan Wang Wen zhang Min zhang MOE International Joint Laboratory of Materials Microstructure Institute for New Energy Materials and Low Carbon TechnologiesSchool of Materials Science and EngineeringTianjin University of TechnologyTianjin 300384China Tianjin Key Laboratory of Organic Solar Cells and Photochemical Conversion School of Chemistry and Chemical EngineeringTianjin University of TechnologyTianjin 300384China

Double-site catalysts have attracted widespread attention in the field of electrocatalysis due to their high metal loading,adjustable active centres,and electronic valence ***,the development of bimetallic sites catalysts that coordinate with definite atoms is still in the exploratory ***,we designed and synthesized a bimetallic palladium complex(BPB-Pd_(2))with conjugated *** supported BPB-Pd_(2)was applied to electrochemical CO_(2)reduction reaction(CO_(2)RR)for the first *** as-obtained BPB-Pd_(2)gives an exceptional Faradaic efficiency of CO(FECO)of 94.4%at−0.80 V *** hydrogen electrode(RHE),which is significantly superior to monoatomic palladium catalyst(BPB-Pd1).The density functional theory(DFT)calculations revealed that the essential reason for the outstanding activity of BPB-Pd_(2)toward CO_(2)RR was that the electronic effect between diatomic palladium reduces the free energy change for CO_(2)RR ***,BPB-Pd_(2)exhibits moderate free energy change to form COOH*intermediate,which was beneficial for the generation of CO in CO_(2)RR.

关键词： synthesis electrocatalysis CO_(2)reduction bimetallic palladium complex synergistic catalysis

N-doped graphene quantum dot-decorated N-TiO2/P-doped porous hollow g-C_(3)N_(4) nanotube composite photocatalysts for antibiotic photodegradation and H2 production

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 165-178页

作者： Jingshu Yuan Yao zhang Xiaoyan zhang Junjie zhang Shen’gen zhang Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China Xi’an Fanyi University Xi’an 710105China Shunde Graduate School of University of Science and Technology Beijing Foshan 528399China State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacao SAR 820000China

Exclusive responsiveness to ultraviolet light (~3.2 eV) and high photogenerated charge recombination rate are the two primary drawbacks of pure TiO_(2). We combined N-doped graphene quantum dots (N-GQDs), morphology regulation, and heterojunction construction strategies to synthesize N-GQD/N-doped TiO_(2)/P-doped porous hollow g-C_(3)N_(4) nanotube (PCN) composite photocatalysts (denoted as G-TPCN). The optimal sample (G-TPCN doped with 0.1wt% N-GQD, denoted as 0.1% G-TPCN) exhibits significantly enhanced photoabsorption, which is attributed to the change in bandgap caused by elemental doping (P and N), the improved light-harvesting resulting from the tube structure, and the upconversion effect of N-GQDs. In addition, the internal charge separation and transfer capability of0.1% G-TPCN are dramatically boosted, and its carrier concentration is 3.7, 2.3, and 1.9 times that of N-TiO_(2), PCN, and N-TiO_(2)/PCN(TPCN-1), respectively. This phenomenon is attributed to the formation of Z-scheme heterojunction between N-TiO_(2) and PCNs, the excellent electron conduction ability of N-GQDs, and the short transfer distance caused by the porous nanotube structure. Compared with those of N-TiO_(2), PCNs, and TPCN-1, the H2 production activity of 0.1%G-TPCN under visible light is enhanced by 12.4, 2.3, and 1.4times, respectively, and its ciprofloxacin (CIP) degradation rate is increased by 7.9, 5.7, and 2.9 times, respectively. The optimized performance benefits from excellent photoresponsiveness and improved carrier separation and migration efficiencies. Finally, the photocatalytic mechanism of 0.1% G-TPCN and five possible degradation pathways of CIP are proposed. This study clarifies the mechanism of multiple modification strategies to synergistically improve the photocatalytic performance of 0.1% G-TPCN and provides a potential strategy for rationally designing novel photocatalysts for environmental remediation and solar energy conversion.

关键词： N-doped TiO_(2) N-doped graphene quantum dots P-doped g-C_(3)N_(4) porous hollow nanotube heterojunction photocatalysis

白细胞介素1及白细胞介素8在心肌缺血再灌注损伤中的动态演变及药物干预效果

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中国组织工程研究与临床康复 2007年第45期11卷 9083-9086页

作者：张艳芳张俊河杨廷桐李磊生物化学与分子生物学教研室新乡医学院形态学实验室

目的:在心肌缺血再灌注损伤中,炎症细胞因子参与其过程的多个环节。实验拟验证白细胞介素1、白细胞介素8因子在此过程中的动态变化,并分析其与药物干预的关系。方法:实验于2005-10/2006-11在新乡医学院形态学实验室完成。①实验分组:选... 详细信息

目的:在心肌缺血再灌注损伤中,炎症细胞因子参与其过程的多个环节。实验拟验证白细胞介素1、白细胞介素8因子在此过程中的动态变化,并分析其与药物干预的关系。方法:实验于2005-10/2006-11在新乡医学院形态学实验室完成。①实验分组:选择健康Wistar成年大鼠70只,按随机数字表法分为3组:对照组(n=10)、模型组(n=30)和药物组(n=30)。后两组又分为缺血0.5h,再灌注2,4,8,12,24h6个时相点,每个时相点5只。对照组只设12h一个时相点作为总体对照。②实验方法:大鼠麻醉后,药物组在右股静脉注入甲泼尼龙(30mg/kg),对照组及模型组注入生理盐水(0.75mg/kg)。采用夹闭左冠状动脉前降支建立大鼠心肌缺血再灌注损伤模型。对照组只开胸不夹闭。③实验评估:在各时相点观察各组大鼠缺血再灌注后的心肌细胞改变;血清学检测白细胞介素1、白细胞介素8因子的动态表达。结果:①模型组缺血再灌注12h炎细胞浸润最显著,药物组炎细胞呈散在浸润。②模型组和药物组白细胞介素1、白细胞介素8因子质量浓度明显高于对照组[缺血再灌注8h为例,白细胞介素1分别为(99.21±14.37),(85.77±11.31),(21.87±10.32)ng/L;白细胞介素8分别为(794.85±24.07),(536.95±19.72),(103.94±11.59)ng/L,P<0.05],峰值分别在缺血再灌注4,8h;同时相点药物组白细胞介素1、白细胞介素8因子质量浓度明显低于模型组(P<0.05)。结论:白细胞介素1和白细胞介素8因子在心肌缺血再灌注损伤的炎症反应中发挥着重要作用;甲泼尼龙对缺血再灌注损伤心肌有保护作用。

关键词：心肌缺血再灌注损伤炎症反应白细胞介素1 白细胞介素8 甲泼尼龙

Reversing free-electron transfer of sulfide cocatalyst for exceptional photocatalytic H_(2)evolution

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Journal of Materials Science & Technology 2024年第4期171卷 147-149页

作者： Yanfeng zhang Zhenyi zhang National Experimental Chemistry Teaching Center Hebei Key Laboratory of Inorganic Nano-materialsCollege of Chemistry and Materials ScienceHebei Normal UniversityShijiazhuang 050024China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China

Recently,Yu and co-workers deeply explore the potential impact of free electron transfer between co-catalysts and photocatalyst carriers on H_(2)evolution efficiency of active sites over MoS_(2+x).They pro-pose an electron-reversal tactics to evade the unexpected electron transfer and synchronously regulate the above transfer in a beneficial orientation for weakening hydrogen adsorption on S ***,this highlight not only discusses and summarizes the essences of electron reversal and the optimized H ad-sorption/desorption mechanism,but also emphasizes the significance of femtosecond transient absorp-tion spectroscopy(fs-TAS)and in-situ irradiated X-ray photoelectron spectroscopy(ISI-XPS)for revealing charge transfer dynamics and *** anticipate that this highlight can disseminate a new per-spective on the roles of photocatalyst carriers in improving cocatalytic H_(2)-production kinetics.

关键词： Photocatalysis Cocatalyst Electron reversal Antibonding-orbital occupancy S–H bonds