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Interface reaction during titanium alloys investment casting by residue gas in ceramic mold

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Rare Metals 2019年第4期38卷 327-335页

作者： Ya-Meng Wei Zhi-Gang Lu xin-Yi Li xin guo Department of Mechanical Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084 China Academy of Opto-Eletronics Chinese Academy of Sciences Beijing 100094 China

The chemical reaction between mold material and titanium melt during investment casting was studied intensively. However, the in fluence of residue gas in ceramic mold on interface reaction remains unclear. In this investigation, the effect of residue gas in Y2O3-silica sol shell mold on interface reaction during Ti-6A1-4V alloy investment casting was investigated. Two groups of shell molds were prepared by adding different kinds of pore formers, i.e., spherical starch particles or nylon fibers, respectively. Ti-6Al-4V alloy was cast under vacuum by gravity casting through cold crucible induction melting (CCIM) method. Porosity of different shell molds was measured based on Archimedean method. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) were employed to characterize the micromorphology and composition of the reaction area, respectively. White light interferometer (WLI) was used to obtain the surface topography of the shell mold. The results show that the direct chemical reaction is very weak for all specimens. The release of residue gas in closed pores is the key factor influencing surface defects. However, open pores make nearly no difference on the interface reaction.

关键词： Titanium alloy Investment casting Residue gas Y2O3: Silica sol

Design and synthesis of ZnCo_(2)O_(4)/CdS for substantially improved photocatalytic hydrogen production

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Frontiers of Chemical Science and Engineering 2023年第5期17卷 606-616页

作者： Xiaohong Li Youji Li xin guo Zhiliang Jin School of Chemistry and Chemical Engineering North Minzu UniversityYinchuan 750021China College of Chemistry and Chemical Engineering Jishou UniversityJishou 416000China

In this study,the hydrogen evolution performance of CdS nanorods is improved using ZnCo_(2)O_(4).ZnCo_(2)O_(4)nanospheres are synthesized using the hydrothermal and calcination methods,and CdS nanorods are synthesized using the solvothermal *** the perspective of morphology,numerous CdS nanorods are anchored on the ZnCo_(2)O_(4)*** to the experimental results of photocatalytic hydrogen evolution,the final hydrogen evolution capacity of 7417.5μmol·g^(-1)·h^(-1)is slightly more than two times that of the single CdS,which proves the feasibility of our *** various characterization methods,it is proved that the composite sample has suitable optoelectronic *** addition,ZnCo_(2)O_(4)itself exhibits good conductivity and low impedance,which shortens the charge-transfer ***,the introduction of ZnCo_(2)O_(4)expands the adsorption range of light and improves the performance of photocatalytic hydrogen *** design can provide reference for developing high-efficiency photocatalysts.

关键词： ZnCo_(2)O_(4)nanosphere CdS nanorods photocatalytic hydrogen evolution

A molecular insight into coke formation process of vacuum residue in thermal cracking reaction

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Petroleum Science 2024年第3期21卷 2130-2138页

作者： Ji-Guang Li xin guo Huan-Di Hou Heavy Oil Processing Department Sinopec Research Institute of Petroleum Processing Co.LtdBeijing100083China

Understanding the coking behaviors has been considered to be really essential for developing better vacuum residue processing technologies.A battery of thermal cracking tests of typical vacuum residue at 410℃ with various reaction time were performed to evaluate the coke formation *** total yields of ideal components including naphtha,atmospheric gas oil(AGO)and vacuum gas oil(VGO)of thermal cracking reactions increased from 10.89%to 40.81%,and the conversion ratios increased from8.05%to 43.33%with increasing the reaction time from 10 to 70 *** asphaltene content increased from 12.14%to a maximum of 22.39%and then decreased,and this maximum of asphaltene content occurred at the end of the coking induction *** asphaltenes during the coking induction period,at the end and after coking induction period of those tested thermal cracking reactions were characterized to disclose the structure changing rules for coke formation process,and the coke formation pathways were discussed to reveal the coke formation process at molecular level.

关键词： Vacuum residue Thermal cracking Asphaltene Coking induction period Sulfur Nitrogen

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美洲黑杨无性系生物质能源林初选试验

东北林业大学学报 2025年第1期53卷 10-14,72页

作者：郭新安胡学孙洪刚张源长中交广州航道局有限公司广州510000 中国林业科学研究院亚热带林业研究所襄阳市测绘研究院

为了探讨美洲黑杨(Populus deltoides)作为生物质能源林的可行性,并进一步筛选更有潜力的适合作为生物质能源林的无性系,以8个美洲黑杨无性系为参试对象,按照随机区组试验营造生物质能源林,并测定了胸径、株高等17个指标,采用多元统计... 详细信息

为了探讨美洲黑杨(Populus deltoides)作为生物质能源林的可行性,并进一步筛选更有潜力的适合作为生物质能源林的无性系,以8个美洲黑杨无性系为参试对象,按照随机区组试验营造生物质能源林,并测定了胸径、株高等17个指标,采用多元统计分析中的主成分分析方法和多元线性回归分析方法,对数据进行了分析。结果表明:8个无性系均为生物质能源林的重要树种,其中,2号无性系最优,其次为4号和3号无性系。采用逐步回归的分析方法,拟定了单株生物量(W)与胸径(D)、株高(H)的回归方程,为W=2.878 7D+0.655 3H-16.528 0,通过测定胸径和株高,可以快速估算其生物量,从而为美洲黑杨生物质能源林经营提供重要参考。

关键词：美洲黑杨无性系能源林

TZ Lyrae:an Algol-type Eclipsing Binary with Mass Transfer

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Chinese Journal of Astronomy and Astrophysics 2007年第2期7卷 258-264页

作者： Yuan-Gui Yang xin-guo Yin Physics Department of Huaibei Coal Industry Teachers College Huaibei 235000

We present a detailed investigation of the Algol-type binary TZ Lyrae, based on 55 light minimum timings spanning 90 years. It is found that the orbital period shows a long-term increase with a cyclic variation superimposed. The rate of the secular increase is dP/dt = ＋7.18 × 10^-8d yr^-1, indicating that a mass transfer from the less massive component to the more massive one at a rate of dra = ＋2.21 × 10^-8M⊙ yr^-1. The cyclic component, with a period of P3 = 45.5 yr and an amplitude of A = 0.^d0040, may be interpreted as either the light-time effect in the presence of a third body or magnetic activity cycles in the components. Using the latest version Wilson-Devinney code, a revised photometric solution was deduced from B and V observations. The results show that TZ Lyr is an Algol-type eclipsing binary with a mass ratio of q = 0.297±0.003）. The semidetached configuration with a lobe-filling secondary suggests a mass transfer from the secondary to the primary, which is in agreement with the long-term period increase of the binary system.

关键词： stars binaries close - stars binaries eclipsing - stars individual TZ Lyrae

Molecular Control of Male Reproductive Development and Pollen Fertility in Rice

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Journal of Integrative Plant Biology 2012年第12期54卷 967-978页

作者： Jing-xin guo Yao-Guang Liu State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources College of Life SciencesSouth China Agricultural University

Anther development and male fertility are essential biological pro- cesses for flowering plants and are important for crop seed produc- tion. Genetic manipulation of male fertility/sterility is critical for crop hybrid breeding. Rice （Oryza sativa L.） male sterility phenotypes, including genic male sterility, hybrid male sterility, and cytoplasmic male sterility, are generally caused by mutations of fertility-related genes, by incompatible interactions between divergent allelic or non-allelic genes, or by genetic incompatibilities between cytoplas-mic and nuclear genomes. Here, we review the recent advances in the molecular basis of anther development and male fertility-sterility conversion in specific genetic backgrounds, and the interactions with certain environmental factors. The highlighted findings in this review have significant implications in both basic studies and rice genetic improvement.

关键词： Anther development cytoplasmic male sterility hybrid sterility male fertility meiosis rice.

Real Interpolation between Martingale Hardy and BMO Spaces

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Acta Mathematica Sinica,English Series 2013年第1期29卷 65-74页

作者： Yan Bo REN Tie xin guo School of Mathematics and Statistics He'nan University of Science and Technology School of Mathematics and Systems Science Beihang University

In this paper, we consider the real interpolation with a function parameter between martingale Hardy and BMO spaces. An interpolation theorem for martingale Hardy and BMO spaces is formulated. As an application, real interpolation between martingale Lorentz and BMO spaces is given. Keywords Martingale space, BMO space, Lorentz space, real interpolation, function parameter

关键词： Martingale space BMO space Lorentz space real interpolation function parameter

On the Random Conjugate Spaces of a Random Locally Convex Module

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Acta Mathematica Sinica,English Series 2012年第4期28卷 687-696页

作者： Tie xin guo Shi En ZHAO LMIB and School of Mathematics and Systems Science Beihang University

Theoretically speaking, there are four kinds of possibilities to define the random conjugate space of a random locally convex module. The purpose of this paper is to prove that among the four kinds there are only two which are universally suitable for the current development of the theory of random conjugate spaces. In this process, we also obtain a somewhat surprising and crucial result： if the base （Ω,F, P） of a random normed module is nonatomic then the random normed module is a totally disconnected topological space when it is endowed with the locally L0-convex topology.

关键词： Random locally convex module (ε λ)-topology locally L0-convex topology random con-jugate space

Dual-salt poly(tetrahydrofuran) electrolyte enables quasi-solid-state lithium metal batteries to operate at -30 ℃

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Journal of Energy Chemistry 2024年第9期96卷 456-463页

作者： Zhiyong Li Zhuo Li Rui Yu xin guo School of Materials Science and Engineering State Key Laboratory of Material Processing and Die&Mould TechnologyHuazhong University of Science and TechnologyWuhan 430074HubeiChina The State Key Laboratory of Refractories and Metallurgy and Institute of Advanced Materials and Nanotechnology Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The stable operation of solid-state lithium metal batteries at low temperatures is plagued by severe restrictions from inferior electrolyte-electrode interface compatibility and increased energy barrier for Li^(+)***,we prepare a dual-salt poly(tetrahydrofuran)-based electrolyte consisting of lithium hexafluorophosphate and lithium difluoro(oxalato)borate(LiDFOB).The Li-salt anions(DFOB−)not only accelerate the ring-opening polymerization of tetrahydrofuran,but also promote the formation of highly ion-conductive and sustainable interphases on Li metal anodes without sacrificing the Li^(+)conductivity of electrolytes,which is favorable for Li^(+)transport kinetics at low *** of this polymer electrolyte in Li||LiFePO_(4)cells show 82.3%capacity retention over 1000 cycles at 30℃and endow stable discharge capacity at−30℃.Remarkably,the Li||LiFePO4 cells retain 52%of their room-temperature capacity at−20℃and 0.1 *** rational design of dual-salt polymer-based electrolytes may provide a new perspective for the stable operation of quasi-solid-state batteries at low temperatures.

关键词： Poly(tetrahydrofuran) Dual-salt electrolyte Solidel ectrolyte interphase Low-temperature operation Quasi-solid-state battery