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Acta Metallurgica Sinica(English Letters) 2023年第3期36卷 366-378页

作者： zhu Wang Guo‑Hui Zhang Yong Yao xue‑hua Fan Jie Jin Lei Zhang Yan‑Xia Du Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China CITIC Pacific Special Steel Group Co. LtdJiangsu 214429China China Petroleum Engineering&Construction Co. Ltd Beijing CompanyBeijing 100085China

The corrosion behaviour of a non-equiatomic CoCrFeNiMo high-entropy alloy(HEA)in H_(2)S-containing and H_(2)S-free environments was studied by electrochemical tests,surface characterization,and solution *** results showed that the HEA exhibited primary and secondary passivation in the H_(2)S-free environment,and the transition was owing to the enhanced dissolution of Fe *** with the primary passive film,the Cr/Fe ratio in the secondary passive film increased at the expense of the selective dissolution of ***,the corrosion resistance of HEA decreased with the applied *** was the most stable element in the film of HEA,regardless of H_(2)*** presence of H_(2)S accelerated the dissolution of all the cationic elements in the HEA.H_(2)S promoted the formation of thicker but less protective surface film and induced the loss of passivity.

关键词： High-entropy alloy(HEA) Corrosion H_(2)S Secondary passivation X-ray photoelectron spectroscopy(XPS) Induced coupled plasma(ICP)

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应用化学专业综合实验的设计研究

实验科学与技术 2010年第1期8卷 123-125页

作者：王彦林钱永赵鑫龚菁朱雪华宫钦德苏州科技学院化学与生物工程学院江苏苏州215009

结合苏州科技学院应用化学专业方向特色,总结了应用化学专业综合性实验开设的经验和效果,探讨了应用化学专业综合性实验的设计原则、思路及特点。指出充分将实验教学和科学研究双重目标和任务结合到一起,精心筛选和设计综合性实验项目,... 详细信息

结合苏州科技学院应用化学专业方向特色,总结了应用化学专业综合性实验开设的经验和效果,探讨了应用化学专业综合性实验的设计原则、思路及特点。指出充分将实验教学和科学研究双重目标和任务结合到一起,精心筛选和设计综合性实验项目,注意实验内容的学科交叉性以及与教师科研项目的结合性,才能取得良好的综合性、创新性和实用性教学效果。

关键词：应用化学综合实验创新效果

Exploring Si/Mg Composite Supported Ziegler-Natta Ti-based Catalysts for Propylene Polymerization

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Chinese Journal of Polymer Science 2017年第12期35卷 1474-1487页

作者： Wei zhu 田洲 Rui-hua Cheng xue-lian He Zhen Liu Ning Zhao 刘柏平 State Key Laboratory of Chemical Engineering East China University of Science and Technology Key Laboratory of Advanced Control and Optimization for Chemical Processes Ministry of Education East China University of Science and Technology

A series of（SiO2/MgO/ID/MgCl2）·TiClx Ziegler-Natta catalysts for propylene polymerization has been prepared with a new method. These catalysts were synthesized using soluble Mg-compounds as the Mg-source and the preparation progress was relatively simple. The catalyst could copy the spherical shape of the carrier very well. The propylene polymerization results showed that the catalyst revealed the best activity with 9,9-di（methoxymethyl）fluorene（BMMF） as internal donor at 50 °C with the optimal molar ratio Al/Ti = 5, which was much lower than what the industrial polypropylene catalyst used（at least molar ratio Al/Ti = 100）, resulting in great cost saving. Additionally, the polymerization kinetics of the catalyst exhibited very stable property after achieving a relatively high value. These catalysts possessed rather high activity and good hydrogen response. The isotactic index（Ⅱ.） value of the PP products could be higher than 98% in the presence of both internal and external electron donors. Moreover, temperature rising elution fractionation method was used to understand the influence of donors and H2 on the properties of the PP products.

关键词： Polypropylene Ziegler-Natta catalyst External donor Intemal donor Kinetic curves

Controlled Freezing and Open-Pulled Straw (OPS) Vitrification of In vitro Produced Bovine Blastocysts FollowingAnalysis of ATP Content and Reactive Oxygen Species (ROS) Level

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Journal of Integrative Agriculture 2012年第3期11卷 446-455页

作者： ZHAO xue-ming DU Wei-hua WANG Dong HAO Hai-sheng QIN Tong LIU Yan zhu hua-bin Embryo Biotechnology and Reproduction Laboratory Institute of Animal Science(IAS)Chinese Academy of Agricultural Sciences(CAAS)Beijing 100193P.R.China

To our knowledge,no single study has systemically compared cryopreservation efficiencies of bovine blastocysts derived from in vitro fertilization （IVF）,intracytoplasmic sperm injection （ICSI） and somatic cell nuclear transfer （SCNT） by controlled freezing and *** experiment,therefore,was designed to compare the cryopreservation of these blastocysts with controlled freezing and OPS ***-5’-triphosphate （ATP） content and reactive oxygen species （ROS） level in blastocysts were also ***,for each type of blastocyst （IVF,ICSI or SCNT）,significant differences were observed between the survival rates of the controlled freezing （（81.56±2.33）,（68.18±4.72） or （47.89±5.83）%） and OPS vitrification groups （（92.24±4.54）,（82.40±3.76） or （78.71±5.91）%;P〈0.05）.Secondly,for each type of blastocyst （IVF,ICSI or SCNT）,ATP content was significantly decreased after controlled freezing or vitrification,and the ATP content in the controlled freezing group （0.43±0.06）,（0.35±0.05） or （0.21±0.02） pmol） was significantly lower than that found in the OPS vitrification group （0.62±0.04）,（0.46±0.03） or （0.30±0.01） pmol;P〈0.05）.Thirdly,ROS level in fresh IVF （（47.33±3.56） c.p.s （counted photons per second）,ICSI （（36.51±2.58） c.p.s） or SCNT blastocysts （（26.44±1.49） c.p.s） was significantly lower than that found in the OPS vitrification group （（72.14±4.31）,（58.89±3.89） or （40.11±5.73） c.p.s;P〈0.05）,but higher than that of the controlled freezing group （34.41±3.32）,（23.13±1.26） or （15.46±2.45） c.p.s;P〈0.05）.The present study indicated that vitrification is more efficient in the cryopreservation of bovine blastocysts derived from IVF,ICSI or SCNT than controlled ***,both vitrification and controlled freezing significantly altered the ATP content and ROS level in those blastocysts.

关键词： ATP content controlled freezing in vitro production blastocysts OPS vitrification ROS level

Controlled growth of complex polar oxide films with atomically precise molecular beam epitaxy

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Frontiers of physics 2018年第5期13卷 9-21页

作者： Fang Yang Yan Liang Li-Xia Liu Qing zhu Wei-hua Wang xue-Tao zhu Jian-Dong Guo Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing 100049 China Collaborative Innovation Center of Quantum Matter Beijing 100871 China

At heterointerfaces between complex oxides with polar discontinuity, the instability-induced electric field may drive electron redistribution, causing a dramatic change in the interracial charge density. This results in the emergence of a rich diversity of exotic physical phenomena in these quasi-two-dimensional systems, which can be further tuned by an external field. To develop novel multifunctional electronic devices, it is essential to control the growth of polar oxide films and heterointerfaces with atomic preci- sion. In this article, we review recent progress in control techniques for oxide film growth by molecular beam epitaxy （MBE）. We emphasize the importance of tuning the microscopic surface structures of polar films for developing precise growth control techniques. Taking the polar SrTiO3 （110） and （111） surfaces as examples, we show that, by keeping the surface reconstructed throughout MBE growth, high-quality layer-by-layer homoepitaxy can be realized. Because the stability of different reconstruc- tions is determined by the surface cation concentration, the growth rate from the Sr/Ti evaporation source can be monitored in real time. A precise, automated control method is established by which insulating homoepitaxial SrTiO3 （110） and （111） films can be obtained on doped metallic substrates. The films show atomically well-defined surfaces and high dielectric performance, which allows the surface carrier concentration to be tuned in the range of -1013/cm2. By applying the knowledge of microstructures from fundamental surface physics to film growth techniques, new opportunities are provided for material science and related research.

关键词： complex oxide films molecular beam epitaxy surface reconstruction heterointerfaces

Analysis of crack opening stresses for center- and edge-crack tension specimens

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Chinese Journal of Aeronautics 2014年第2期27卷 291-298页

作者： Tong Di-hua Wu xue-Ren AVIC Beijing Institute of Aeronautical Materials

Accurate determination of crack opening stress is of central importance to fatigue crack growth analysis and life prediction based on the crack-closure model. This paper studies the crack opening behavior for center- and edge-crack tension specimens. It is found that the crack opening stress is affected by the crack tip element. By taking the crack tip element into account, a modified crack opening stress equation is given for the center-crack tension specimen. Crack surface displace- ment equations for an edge crack in a semi-infinite plate under remote uniform tension and partially distributed pressure are derived by using the weight function method. Based on these displacements, a crack opening stress equation for an edge crack in a semi-infinite plate under uniform tension has been developed. The study shows that the crack opening stress is geometry-dependent, and the weight function method provides an effective and reliable tool to deal with such geometry depen- dence.

关键词： Center- and edge-crack Crack closure Crack opening stresses Crack surface displacements Weight function method

Mean estimation over numeric data with personalized local differential privacy

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Frontiers of Computer Science 2022年第3期16卷 183-192页

作者： Qiao xue Youwen zhu Jian WANG College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Guangxi Key Laboratory of Trusted Software Guilin University of Electronic TechnologyGuilin 541004China School of Cyber Security Gansu University of Political Science and LawLanzhou 730070China

The fast development of the Internet and mobile devices results in a crowdsensing business model,where individuals(users)are willing to contribute their data to help the institution(data collector)analyze and release useful ***,the reveal of personal data will bring huge privacy threats to users,which will impede the wide application of the crowdsensing *** settle the problem,the definition of local differential privacy(LDP)is ***,to respond to the varied privacy preference of users,resear-chers propose a new model,i.e.,personalized local differential privacy(PLDP),which allow users to specify their own privacy *** this paper,we focus on a basic task of calculating the mean value over a single numeric attribute with *** on the previous schemes for mean estimation under LDP,we employ PLDP model to design novel schemes(LAP,DCP,PWP)to provide personalized privacy for each *** then theoretically analysis the worst-case variance of three proposed schemes and conduct experiments on synthetic and real datasets to evaluate the performance of three *** theoretical and experimental results show the optimality of PWP in the low privacy regime and a slight advantage of DCP in the high privacy regime.

关键词： personalized local differential privacy mean estimation crowdsensing model

Electrochemical and corrosion behaviors of the wrought Mg–Y–Zn based alloys with high Y/Zn mole ratios

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Journal of Magnesium and Alloys 2021年第4期9卷 1427-1435页

作者： Xuan Liu Zijian zhu Jilai xue School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China

The electrochemical behaviors and corrosion resistance of the wrought Mg–Y–Zn based alloys with high Y/Zn mole ratio have been investigated in *** results show that the corrosion resistance of the investigated Mg–Y–Zn based alloys are dependent on the modified arrangement of LPSO phase by adjusting Y/Zn mole *** the Y/Zn mole ratio not only greatly decreases the size of LPSO phase plates,but also leads to the precipitation of Mg_(24)Y_(5) *** corrosion rate of Mg–Y–Zn based alloys greatly increases from 7.4 mg·cm^(−2)·day^(−1) to 11.3 mg·cm^(−2)·day^(−1) with increasing the Y/Zn mole ratio up to *** should be attributed to the decreasing size of LPSO phase plates as cathodes,further increasing the hydrogen evolution *** related corrosion mechanism is discussed in details.

关键词： Mg–Y–Zn alloys Y/Zn mole ratio Corrosion resistance Electrochemical behaviors Microstructures

建设企业PMO经理的基本技能评价指标模型研究

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价值工程 2017年第9期36卷 42-44页

作者：苏霖李智平林容黄身勇伊彪朱雪花福建省永泰建筑工程公司永泰350700 中建三局第三建设工程有限责任公司中南分公司武汉430074

为了对项目管理办公室模式中PMO经理基本技能评价指标进行客观评价,提高PMO经理的综合素质。本文在识别PMO经理基本技能评价指标的基础上,采用因子分析法,将基本技能指标归纳为4个类别,构建了基本技能指标体系及评价模型;进一步计算各... 详细信息

为了对项目管理办公室模式中PMO经理基本技能评价指标进行客观评价,提高PMO经理的综合素质。本文在识别PMO经理基本技能评价指标的基础上,采用因子分析法,将基本技能指标归纳为4个类别,构建了基本技能指标体系及评价模型;进一步计算各指标的影响系数,结果表明系统思维、应变能力、语言表达能力、判断规划、沟通技巧以及项目管理专业知识对PMO经理的基本技能影响较大。研究成果为建设企业PMO经理的评价及选拔提供理论指导。

关键词：因子分析法项目管理办公室 PMO经理基本技能

免疫荧光动态监测急性早幼粒细胞白血病患者PML-RARα融合蛋白变化

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中国组织工程研究 2012年第10期16卷 1875-1878页

作者：仇飞张辉赵旭杰朱雪花王侃侃张济上海交通大学医学院附属瑞金医院上海市血液学研究所上海市200025

背景:实时定量RT-PCR只能间接地反映融合基因表达量的变化,并不能在细胞原位直观反映急性早幼粒细胞白血病患者细胞内PML-RARα融合蛋白在全反式维甲酸治疗前后的相对表达量。目的:探讨免疫荧光技术检测融合蛋白PML-RARα表达的动态变... 详细信息

背景:实时定量RT-PCR只能间接地反映融合基因表达量的变化,并不能在细胞原位直观反映急性早幼粒细胞白血病患者细胞内PML-RARα融合蛋白在全反式维甲酸治疗前后的相对表达量。目的:探讨免疫荧光技术检测融合蛋白PML-RARα表达的动态变化在判断急性早幼粒细胞白血病的全反式维甲酸早期治疗的效果。方法:应用免疫荧光技术检测全反式维甲酸干预的急性早幼粒细胞白血病经典细胞株NB4细胞或来源于急性早幼粒细胞白血病患者的NB4细胞PML-RARα蛋白的表达,以实时定量RT-PCR检测细胞PML-RARα mRNA的表达作为对照,以评价免疫荧光技术的可靠性。结果与结论:免疫荧光染色显示,无论是体外培养的NB4细胞,还是患者骨髓内的NB4细胞,在全反式维甲酸干预前细胞内均可见大量红色的融合蛋白PML-RARα,大小不均一、形状不规则,全反式维甲酸干预后,NB4细胞内红色的融合蛋白PML-RARα形状逐渐规则,弥散状态变为散在分布,且随着全反式维甲酸干预时间的延长,原有的弥散状态逐渐消失。实时定量RT-PCR测得的PML-RARα mRNA的变化趋势与免疫荧光相一致。说明免疫荧光技术检测PML-RARα能够更为直观地判断全反式维甲酸的治疗效果。

关键词：免疫荧光实时定量RT-PCR PML-RARα 急性早幼粒细胞白血病 NB4细胞 U937细胞