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Synthesis of GdF_3 from the Gd_2O_3-NH_4HF_2 system

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Rare Metals 2007年第5期26卷 482-487页

作者： HAO Zhanzhong zhang Jianliang WANG Bin zhang xidong Metallurgical and Ecological Engineering School University of Science and Technology Beijing Beijing 100083 China Baotou Teachers College Baotou 014030 China

GdF3 was synthesized with Gd2O3 and NH4HF2 under atmospheric pressure and vacuum. The effects of pressure,temperature,and reactant ratio on the reaction process were investigated. A new mechanism for the synthesis of GdF3 was proposed. Powdered Gd2O3 started to react with NH4HF2 at low temperature,and the products were GdNH4F4,NH4F,NH3,and H2O. GdNH4F4 decomposed to GdF3 and NH4F after further high-temperature treatment,accompanying the volatilization and decomposition of NH4F. The whole process could be divided into three steps： synthesis,decomposition,and deamination. The initial and final reaction temperatures decreased under vacuum condition. An optimized process for the preparation of GdF3 was obtained： synthesis under atmospheric pressure at low temperature and decomposition and deamination under vacuum at high temperature.

关键词： inorganic chemistry Gd NH4HF2 synthesis

Three-dimensional flexible Au nanoparticles-decorated TiO_(2) nanotube arrays for photoelectrochemical biosensing

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Journal of Materials Science & Technology 2020年第21期56卷 162-169页

作者： xidong zhang Dong Yue Ling zhang Shiwei Lin State Key Laboratory of Marine Resource Utilization in South China Sea School of Materials Science and EngineeringHainan UniversityHaikou 570228China

Controlling the charge transfer and thus enhancing the excitons’lifetime are the key to the realization of efficient photoelectrochemical(PEC)***,fabrication of flexible and collapsible sensors can greatly facilitate the implementation of smart PEC sensing devices into practical ***,we sagely designed and successfully fabricated three-dimensional flexible Au nanoparticles-decorated TiO_(2) nanotube arrays(Au@TiO2)for the efficient PEC biosensing of *** Schottky barrier derived from the Au@TiO2 heterostructure efficiently separates the charge carriers at the junction interfaces,thus greatly increasing the concentration and lifetime of holes left in the valence band of *** separated holes further evidently generate the active hydroxyl radicals,which can specifically recognize and oxidize *** a result,Au@TiO_(2) exhibits excellent photoelectric activity and selectivity,far superior to TiO_(2) without decorated Au *** addition,such asymmetric Au@TiO_(2) system has been proved to feature the intrinsic flexibility nature,since its PEC biosensing performance is almost unaffected under indirect light irradiation and serious tensile strain.

关键词： Photoelectrochemical biosensing Metal/semiconductor interface Flexibility TiO_(2)nanotube arrays

Novel titanium particles reinforced Zr-based bulk metallic glass composites prepared by infiltration casting

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Journal of University of Science and Technology Beijing 2008年第4期15卷 505-508页

作者： Cuimei zhang xidong Hui Meiling Wang Guoliang Chen State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

A novel Ti/Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 composite was successfully prepared by infiltrating the melt into sintered Ti preform. It shows that the introduction of Ti particles into the composite results in an increase in elastic strain to 3% and an enhancement of the strength up to 2.1 GPa. High specific strength has been obtained because of the decrease in density of the composite. It is suggested that an improvement in the mechanical properties of the composite may be attributed to the generation of multiple shear bands and some deformation in the Ti particles.

关键词： melt infiltration bulk metallic-glass Ti particles mechanical properties

Clinical Efficacy of Recombinant Brain Natriuretic Peptide in Patients with Acute Myocardial Infarction After On-Pump Coronary Artery Bypass Grafting (CABG)

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Proceedings of Anticancer Research 2019年第6期3卷 15-18页

作者： xidong zhang Department of cardiac surgery Anhui Provincial HospitalHefeiChina

Objective:To evaluate the clinical efficacy of intravenous recombinant human brain natriuretic peptide(rhBNP)in patients with acute myocardial infarction after on-pump coronary artery bypass grafting(CABG).Methods:40 cases of coronary heart disease,left ventricular ejection fraction300 pg/ml underwent on-pump coronary artery bypass surgery with cardiopulmonary bypass were enrolled and randomly divided into two groups,experimental group of 20 patients after operation on the basis of conventional therapy plus recombinant human brain natriuretic peptide treatment(first loading dose of 1.5μg/kg intravenously,to maintain dose of 0.01μg/kg/min continuous infusion of 72h),20 cases of the control group was given routine treatment,observe two groups of patients before and after treatment of blood pressure,heart rate,urine volume,blood creatinine and NT-proBNP,and to observe the left ventricular ejection fraction(LVEF),echocardiography and the length of time the ***:the experimental group after treatment,urine volume,left ventricular ejection fraction(LVEF),cardiac index(CI)was significantly higher than that before treatment,the serum creatinine,plasma N-terminal pro brain natriuretic peptide(NTproBNP),the content of serum troponin T peptide(cT nT),creatine kinase isoenzyme(CK MB)was significantly lower than before ***:Recombinant human brain natriuretic peptide can improve cardiac and renal function in patients with acute period of acute myocardial infarction underwent coronary artery bypass surgery,shorten the hospitalization time,and it is safe and feasible.

关键词： Natriuretic peptide Brain Coronary artery bypass grafting Myocardial infarction Renal function Hemodynamics

维普期刊数据库评论

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圆柱绕流中扰动体强化传热和减阻

化工学报 2014年第2期65卷 488-494页

作者：张喜东黄护林南京航空航天大学高新技术研究院江苏南京210016

以圆柱上游布置扰动体的双钝体绕流模式为研究对象，通过有限体积法数值研究了 Reynolds 数 Re=1000时钝体直径比（d/D）、间隙率（S/D）对双钝体系统传热性能和系统阻力的影响规律。结果表明，小直径扰钝体对系统的对流换热更为有利，... 详细信息

以圆柱上游布置扰动体的双钝体绕流模式为研究对象，通过有限体积法数值研究了 Reynolds 数 Re=1000时钝体直径比（d/D）、间隙率（S/D）对双钝体系统传热性能和系统阻力的影响规律。结果表明，小直径扰钝体对系统的对流换热更为有利，且系统的对流换热随间隙率的增大而递增。以等直径双钝体（d/D=1）系统为基准，总换热增长量（HI）随间隙率和扰动体直径的增大而减小，且间隙率小于临界值（S/D=4）时换热增长量波动比较明显。当d/D=0.1，S/D≥5时，系统的换热增长量为22.3%～25%，且此时系统的流动阻力可减小约40%，这表明上游小直径扰动体的利用在增强系统换热性能的同时也减小了系统的阻力。

关键词：扰动体换热换热增长量流动阻力对流

Facile synthesis and photoelectrochemical properties of novel TiN/C3N4/CdS nanotube core/shell arrays

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Chinese Journal of Catalysis 2020年第10期41卷 1645-1653页

作者： Changzhi Ai Li Tong Zhipeng Wang xidong zhang Guizhen Wang Shengjue Deng Jin Li Shiwei Lin State Key Laboratory of Marine Resource Utilization in South China Sea Hainan UniversityHaikou 570228HainanChina School of Materials Science and Engineering Hainan UniversityHaikou 570228HainanChina College of Materials Science and Engineering Zhejiang UniversityHangzhou 310027ZhejiangChina School of Science Hainan UniversityHaikou 570228HainanChina

Recently, the g-C3N4-based heterojunctions have been widely investigated for their greatly enhanced photogenerated carrier separation efficiency. However, most studies are based on the study of g-C3N4 powders. In this study, a novel TiN/C3N4/CdS nanotube arrays core/shell structure is designed to improve the photoelectrochemical catalytic performance of the g-C3N4-based heterojunctions. Among them, TiN nanotube arrays do not respond to simulated solar light, and thus only serve as an excellently conductive nanotube arrays backbone for supporting g-C3N4/CdS heterojunctions. g-C3N4 prepared by simple liquid atomic layer deposition, which possesses appropriate energy band position, mainly acts as the electron acceptor to transport and separate electrons. Deposited CdS quantum dots obtained by successive ionic layer adsorption reaction can effectively absorb visible light and thus act as a light absorber. The TiN/C3N4/CdS nanotube arrays core/shell structure could be verified by X-ray diffractions, Raman spectra, scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy elemental mappings and X-ray photoelectron spectroscopy. Compared with TiN/C3N4 nanotube arrays, the TiN/C3N4/CdS samples greatly improve the photoelectrochemical performance, which can be evaluated by photoelectrochemical tests and photoelectrochemical catalytic degradation. Especially, the optimized photocurrent density of TiN/C3N4/CdS has almost 120 times improvement on TiN/C3N4 at 0 V bias under simulated sunlight, which can be ascribed to the effective expansion of the light absorption range and separation of electron-hole pairs.

关键词： TiN g-C3N4/CdS PEC catalysis Degradation Nanotube arrays

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双向循环荷载下黄土的动变形特性研究

地震工程与工程振动 2016年第1期36卷 186-192页

作者：张希栋骆亚生西北农林科技大学水利与建筑工程学院陕西杨凌712100

利用SDT-20型动三轴仪在双向循环荷载下探究了黄土的动变形特性,分析了初始循环偏应力、径向动荷载幅值和预剪应力对黄土动变形发展的影响。试验结果表明:双向循环荷载作用下,初始动应力状态对黄土破坏模式有重要影响,初始循环偏应力小... 详细信息

利用SDT-20型动三轴仪在双向循环荷载下探究了黄土的动变形特性,分析了初始循环偏应力、径向动荷载幅值和预剪应力对黄土动变形发展的影响。试验结果表明:双向循环荷载作用下,初始动应力状态对黄土破坏模式有重要影响,初始循环偏应力小于0 k Pa时,黄土呈受拉破坏,初始循环偏应力大于0 k Pa时,黄土呈受压破坏。初始循环偏应力、径向动荷载幅值和预剪应力对黄土的动剪切变形均有明显的影响,初始循环偏应力和径向动荷载幅值的增大均加快了黄土的动剪切变形发展,使土体的破坏更迅速。预剪应力对土体起到预压密作用,黄土的动剪切变形的发展随预剪应力的增大而减缓。当剪切动荷载幅值保持不变时,拉压动荷载幅值的增大明显地加速了黄土动剪切变形的发展,其对土体动剪切变形的影响和剪切动荷载是一致的。

关键词：双向循环荷载黄土动剪切变形初始循环偏应力径向动荷载幅值预剪应力

行政垄断、政府管制与产业绩效——对天然气开采业的一般均衡分析

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北京理工大学学报（社会科学版） 2015年第6期17卷 38-45页

作者：张希栋张晓中国社会科学院研究生院北京102488 中国社会科学院数量经济与技术经济研究所北京100732

通过构建新古典闭合框架下的静态可计算一般均衡(Computable General Equilibrium,CGE)模型,模拟天然气开采业取消政府管制对经济增长、居民福利以及产业绩效的影响。模拟结果显示:无论是在短期内还是长期内取消政府管制不仅能够拉动GD... 详细信息

通过构建新古典闭合框架下的静态可计算一般均衡(Computable General Equilibrium,CGE)模型,模拟天然气开采业取消政府管制对经济增长、居民福利以及产业绩效的影响。模拟结果显示:无论是在短期内还是长期内取消政府管制不仅能够拉动GDP增长、增加居民收入、改善居民福利,还能够有效降低天然气开采业部门的生产成本、提高生产效率、增加天然气的产量、促进天然气的最终消费。因此,应该逐渐打破政府对天然气开采业的行政垄断,降低政府对市场的不合理干预,逐步建立自由竞争的市场。

关键词：天然气开采业行政垄断政府管制可计算的一般均衡模型

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硫－磷型中负荷工业齿轮油系列产品的研制

石油炼制与化工 1996年第2期27卷 34-40页

作者：张希栋石油化工科学研究院

以南阳原油生产的中性油为基础油，用含硫、磷的极压／抗磨添加剂为主剂制备的硫一磷型中负荷工业齿轮油系列产品，经模拟评定试验和使用试验，表明其性能符合ＡＧＭＡ２５０·０３ＥＰ和ＧＢ５９０３规格标准，达到了国外同类产品水平。

关键词：齿轮油负荷中负荷润滑油硫-磷型