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Journal of Magnesium and Alloys 2022年第4期10卷 956-964页

作者： Yuzhi Zhu Dewen hou Qizhen li School of Mechanical and Materials Engineering Washington State UniversityPullmanWA 99164United States Micron School of Materials Science and Engineering Boise State UniversityBoise 83725-1030 IDUnited States

Twinning and detwinning behavior,together with slip behavior,are studied in a textured AZ31 magnesium alloy under compressive and tensile strains along the rolling direction(RD)after each interrupted mechanical test via quasi in-situ electron backscattered diffraction *** results show that twinning firstly takes place under the compressive strain along the *** the increasing compressive strain,{1012}tensile twins firstly nucleate,then propagate,and finally *** under a reversed tensile strain along the RD,detwinning *** nucleation happens during ***,tensile twins can detwin at lower tensile strain,followed by thinning,shortening,and *** are also activated to accommodate the plastic *** the matrix,prismatic slip can only dominate at relatively high ***,basal slip *** in the twins,prismatic slip can activate at lower strains,which is ascribed to the texture reorientation.

关键词： Magnesium alloy Twinning Detwinning Prismatic slip quasi in-situ EBSD

Synthesis of Pb(OH)2/rGO Catalyst for Conversion of Sugar to Lactic Acid in Water

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Chinese Journal of Chemical Physics 2015年第4期28卷 -页

作者： Guan-hua hou li-feng Yan Department of Chemical Physics Collaborative Innovation Center of Chemistry for Energy Materials (iChEM) University of Science and Technology of China Hefei 230026 China

Conversion of sugars from biomass to platform chemicals or fuels is an attracting topic for the utilization of biomass. Pb2+ ion is an efficient catalyst for the degradation of sugar to lactic acid, and it will be better to fix lead on a solid catalyst to reduce the risk of exposure of Pb2+ to environment. Here, a simple method has been developed to prepare a composite catalyst of Pb(OH)2/rGO, where the nanoparticles of Pb(OH)2 in size of 2–5 nm were prepared and fixed over the as-prepared reduced graphene oxide (rGO) nanosheets. The as-obtained catalyst showed an efficient catalytic activity to degrade glucose, fructose, and cellulose in aqueous solution, and the major product is lactic acid. The yield of lactic acid reached 58.7% when fructose was used as the feedstock (433 K and 2.5 MPa N2), and the catalyst can be recycled with high activity. Cellulose can also be directly converted into lactic acid in aqueous solution over the catalyst without extra acid or alkali, and the maximum yield of lactic acid is 31.7%.

关键词： Graphene Lead hydroxide Nanoparticles Composite Catalyst Lactic acid

Dual-threshold symbol selective relaying in cooperative networks

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Journal of Systems Engineering and Electronics 2017年第6期28卷 1057-1063页

作者： Peiyao Yang Hai li Shujuan hou School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

In order to efficiently mitigate error propagation and reduce computational complexity, this paper proposes a scheme for traditional cooperative networks, named as dual-threshold symbol selective demodulate-and-forward. In the scheme, two log likelihood ratio(LLR)-based thresholds are devised to measure the reliability of received signals for the relay and the destination, respectively. One of the threshold guarantees that the relay only forwards reliable symbols, thus less error will be propagated to the destination. The other threshold is used at the destination for determining the reliability of symbols received from the *** destination will directly demodulate reliable symbols received from the source. Otherwise, when the symbols received from the source are not reliable, the maximum ratio combiner(MRC) is used to combine symbols received from the source and the ***-form expression of the bit error probability(BEP) of the proposed scheme is derived and analyzed under binary phase shift keying(BPSK) modulation. Then, the relationship and closed-form solutions of two LLR-based thresholds are derived. Simulation results prove that the theoretical BEP of the proposed scheme closely matches the simulated ones. The proposed scheme can achieve high performance with low computational complexity compared to existing schemes.

关键词： demodulate-and-forward relaying strategies error propagation cooperative networks

Coordination Structure of Aluminum in Magnesium Aluminum Hydroxide Studied by (27)Al NMR

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Chinese Chemical Letters 2003年第6期14卷 605-608页

作者： Shu Hua HAN Wan Guo hou Wen xiu DANG Jun XU Key Lab of Colloid and Interface Chemistry of State Education Ministry Shandong UniversityJinan 250100

The coordination structure of aluminum in magnesium aluminum hydroxide was studied by 27Al NMR. The result showed that tetrahedral aluminum (AliV) existed in magnesium aluminum hydroxide, and the contents of AliV increased with the increase of the ratio of Al/Mg and with the peptizing temperature. AliV originated from the so-called Al13 polymer with the structure of one Al tetrahedron surrounded by twelve Al octahedrons.

关键词： Coordination structure magnesium aluminum hydroxide 27Al NMR.

One inorganic–organic hybrid derived from reduced molybdophosphate and trinuclear cadmium(II) fragment

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Chinese Chemical Letters 2013年第10期24卷 877-880页

作者： xiu-li Wang Jing-Jing Cao Ji-lin hou Guo-Cheng liu Dan Zhao Xiao-Jing liu Na li Ai-Xiang Tian Department of Chemistry Bohai UniversityLiaoning Province Silicon Materials Engineering Technology Research Center

One new polyoxometalate （POM）-based inorganic-organic hybrid [Cdn3~HPO4）（Hbpp）（H20）2]{CdII[P4_ Mo6028H3.s（OH）312}.（H4tpb）.7H20 （1）（bpp = 1,3-bis-（4-pyridyl）propane, tpb = 1,2,4,5-tetra（4-pyridyl）- benzene） constructed from reduced molybdophosphate [P4Mo6028H3.5（OH）3]s＇5- （P4Mo6）, trinuclear Cdn-phosphate-Hbpp fragment and protonated tpb has been hydrothermally synthesized and structurally characterized by IR, elemental analyses and single crystal X-ray diffraction. The complex 1 crystallizes in the monoclinic system with the space group P21]c and cell parameters of a=15.672（12）A, b=23.839（19）A, c=27.654（2）,~, fl=115.850（10）~, V=9297.9（12） ~3, Z=4, R1 ~0.0534 and wR2 ~0.1135. In complex 1, the P4Mo6 units are bridged by CdII ions to form the classic sandwich-type [Cd（P4Mo6）2] dimers, which are further connected into a two dimensional network via the trinuclear Cdn subunits. The tpb is synthesized in situ from the bpp ligands and connects the adjacent 2D layers into a 3D supramolecular framework through hydrogen bonding interactions. The electrochemical and fluorescent properties of complex 1 have been investigated.

关键词： Reduced molybdophosphate Cadmium(ll) complex In situ synthesis Multi-pyridine ligand

Curcumin inhibits proliferation of human lens epithelial cells:a proteomic analysis

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第5期13卷 402-407页

作者： Yan-hong HU xiu-rong HUANG Ming-xin QI Bu-yuan hou Department of Ophthalmology the Second Affiliated Hospital of Fujian University of Traditional Chinese MedicineFuzhou 350003China Research Center of Pathophysiology Fujian University of Traditional Chinese MedicineFuzhou 350003China

Objective: The incidence of after-cataracts [also known as posterior capsular opacification (PCO)] is between 30% and 50% three years following cataract surgery. Suppressing the proliferation of lens epithelial cells (LECs) is a primary goal in preventing PCO. Here, we investigated the proteomic regulation of the inhibitory effects of curcumin (Cur) on the proliferation of human lens epithelial B3 (HLE-B3) cells. Methods: Recombinant human basic fibroblast growth factor (rhbFGF) was used to induce proliferation of HLE-B3 cells, which were incubated with 20 mg/L Cur in a CO2 incubator for 24 h. Results: We found that the absorbance (A) value of rhbFGF group was significantly higher than the A value of the control group. Furthermore, the A value of the Cur group was significantly lower com- pared to the rhbFGF group, with an inhibition of 53.7%. Five different protein spots were obtained from proliferative HLE-B3 cells induced by rhbFGF. Eight different protein spots were obtained in HLE-B3 cells incubated with Cur. There were the common variational protein spots at mass/charge (m/z) ratios of 8 093 and 13 767 between rhbFGF group and control group as well as between the Cur group and rhbFGF group. Conclusions: These results show that Cur effectively inhibited HLE-B3 cell proliferation induced by rhbFGF. The protein spots at m/z of 8 093 and 13 767 may be the targets of Cur-induced inhibition of HLE-B3 cell proliferation. Cur may be a reliable and effective drug for pre- vention and treatment of polymerase chain reaction (PCR).

关键词： Curcumin After-cataract Posterior capsular opacification (PCO) Proteomics Lens epithelial cells

J/ψ production in p+p and p+Pb collisions at ultrarelativistic energies

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Nuclear Science and Techniques 2018年第8期29卷 179-185页

作者： Hong-Min Wang Zhao-Yu hou xiu-Ting Wang Xian-Jing Sun Physics Department Academy of Army Armored Forces of PLA Physics Graduate School Shijiazhuang Railway Institute Institute of High Energy Physics Chinese Academy of Sciences

The production of J/ψ mesons in p+p and p+Pb collisions is studied in the framework of color-glass condensate together with a simple color evaporation *** the nuclear effects with the Glauber–Gribov approach,we calculate the cross section and the nuclear modification factor of forward J/ψ production in p+Pb collisions at s^(1/2) 5:02 ***,the backward J/ψ production in p+Pb collisions at s^(1/2) 8:16 Te V is also *** our calculation,the phenomenology KLRAd S/CFT model and the rc BK approach,which are valid at a small x,are used to calculate the three-point *** is shown that the theoretical results fit well with the experimental data from AliCE and LHCb.

关键词：碰撞生产 Glauber 精力 J/ψ 修正因素冷凝物现象学

Theoretical Calculations for Elastic Scattering of Electrons from Xe Atom

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Chinese Physics Letters 1991年第2期8卷 74-77页

作者： hou Qing li Jiaming Institute of Physics Academia SinicaBeijing 100080

The differential cross sections and spin polarization parameters for the spin-electrons elastically scattered from spinless Xe atoms are calculated by relativistic partial expansion *** the processes the incident electrons are treated as moving relativistically in an effective central potential V(r)which is calculated by relativistic self-consistent-field method with Slater local exchange *** validity of the theoretical method can be accessed by detailed comparison with recent complete experimental data.

关键词： method. relativistic Elastic

光稀释效应对O_(2)近红外气辉星载测风的影响

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光谱学与光谱分析 2025年第1期45卷 160-169页

作者：李昊天李发泉李娟王后茂武魁军何微微烟台大学物理与电子信息学院山东烟台264005 中国科学院精密测量科学与技术创新研究院湖北武汉430071 中国科学院西安光学精密机械研究所陕西西安710119 中国科学院国家空间科学中心北京100190

利用星载光谱成像干涉仪测量O_(2)(a^(1)Δ^(g))日辉的多普勒频移信息是目前实现全球临近空间大气风场探测的先进技术手段,观测谱线O 19 P 18(7772.030 cm^(-1))的多普勒频移,可以在40~80 km的空间区域进行高精度和高灵敏度的风速测量,... 详细信息

利用星载光谱成像干涉仪测量O_(2)(a^(1)Δ^(g))日辉的多普勒频移信息是目前实现全球临近空间大气风场探测的先进技术手段,观测谱线O 19 P 18(7772.030 cm^(-1))的多普勒频移,可以在40~80 km的空间区域进行高精度和高灵敏度的风速测量,然而其探测精度受大气散射的具体影响尚不明晰。文章旨在分析光稀释效应对临近空间大气风场探测的影响,并对其引起的测风误差进行定量评估。首先介绍了O_(2)(a^(1)Δ^(g))光谱和大气散射的光谱特性。采用最新的HITRAN光谱参数、光化学反应速率常数以及大气模型计算得到O_(2)(a^(1)Δ^(g))不同反应机制的贡献。结合光化学反应速率计算得到O_(2)(a^(1)Δ^(g))的体辐射率,并分析了太阳天顶角对体辐射率分布的影响,基于爱因斯坦系数和谱线强度分别计算得到O_(2)(a^(1)Δ^(g))在不同温度和自吸收效应条件下的光谱辐射模型,并分析了不同地理气象因素对大气散射光谱造成的影响。其次,介绍了临边观测多普勒非对称空间外差光谱仪(DASH)的测量技术原理,描述了如何去除大气散射分量以生成纯净的气辉干涉图,基于DASH仪器概念对获取干涉图像的正演过程进行了阐释。再次,针对反演问题引入了“剥洋葱算法”,在考虑自吸收效应和光稀释效应影响的情况下,消除了目标层上方大气层贡献,解决了干涉图像中目标层信息的提取问题。最后,通过误差分析得到了大气风场探测精度廓线及其随地理气象因素影响的变化规律,证明光稀释效应的存在降低了干涉图对比度并增加了测量噪声,这对临边观测权重和有效信噪比产生了不利影响。研究表明,在45~80 km的切线高度范围内,测风精度受大气散射的影响较小,其误差约为2~3 m·s^(-1);而在45 km以下,测风精度受光稀释效应的影响随海拔高度的降低而急剧增大,且受地表反照率、气溶胶和云量等因素的影响而显著升高,在同时考虑三种因素影响的情况下,其探测下限最低约为40 km。

关键词：临近空间光稀释效应测量精度大气风场光学仪器

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微带交指带通滤波器小型化结构设计

现代电子技术 2025年第1期48卷 112-116页

作者：蒋建华张杨侯明李晓珍柳铁铁道职业技术学院广西柳州545616 昆明理工大学信息工程与自动化学院云南昆明650504 昆明学院信息技术学院云南昆明650214

文中提出在终端短路式交指带通滤波器的开路端引入一段微带加载线,使谐振器产生尺寸跳变。通过改变微带加载线的线宽,增加谐振器的等效电感值,从而实现降低该带通滤波器中心频率的目的,并且给出了在设计指标下,随加载线宽变化中心频率... 详细信息

文中提出在终端短路式交指带通滤波器的开路端引入一段微带加载线,使谐振器产生尺寸跳变。通过改变微带加载线的线宽,增加谐振器的等效电感值,从而实现降低该带通滤波器中心频率的目的,并且给出了在设计指标下,随加载线宽变化中心频率变化的经验公式。对X波段的微带交指带通滤波器和微带线尺寸跳变进行了研究,研究数据表明:谐振器越短,中心频率往高频偏移越多;微带线尺寸跳变越大,中心频率往低频偏移越多。通过合理减小谐振器长度和增加微带加载线线宽,滤波器整体长度减小而宽度不变,且改进前后滤波特性不发生改变,达到了滤波器小型化的目的。通过在HFSS中建立滤波器模型并进行仿真,改进后增加了传输零点,回波损耗更加稳定,谐振器长度减小10%,微带加载线线宽增加0.15 mm,整体滤波器尺寸减小10%,验证了所提出结构的可行性。

关键词：带通滤波器交指型微带加载线小型化 HFSS 谐振器