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Acta Metallurgica Sinica(English Letters) 2022年第6期35卷 1023-1033页

作者： Yong Yang xue-Ling hou Mou-Cheng Li Institute of Materials School of Materials Science and EngineeringShanghai UniversityShanghai 200072China

Pitting initiation and stable propagation behaviors of 2205 duplex stainless steel were investigated in the hot concentrated seawater under vacuum pressures by potentiostatic polarization. Both applied potentials and vacuum pressures greatly influence the pitting corrosion. Higher potentials lead to much faster stable pitting initiation and growth rates in both static(101.3 kPa) and dynamic(28.4 kPa) solutions. The pressure reduction can also accelerate the pitting initiation rate. However, the boiling of solution can influence the pitting propagation mechanism. The dynamic actions of boiling bubbles are unfavorable to the pit propagation and result in the formation of relatively smooth pit bottom without secondary pits.

关键词： Duplex stainless steel Stable pitting Vacuum pressure Hot concentrated seawater Potentiostatic polarization

Addition of Allyltrimethylsilane to tert-Butanesulfinyl Imines Triggered by Tetra-n-butylammonium Fluoride

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Chinese Chemical Letters 2006年第8期17卷 1037-1040页

作者： Wan Xuan ZHANG xue Long hou Ministry-of-Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules Faculty of Chemistry and Material Science Hubei University Wuhan 430062 State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032

The addition of allyltrimethylsilane to tert-butanesulfinyl imines triggered by tetra-n-butylammonium fluoride （TBAF） in the presence of 4A molecular sieves has been studied, and homoallylsulfinamides were obtained ... 详细信息

关键词： Stereoselective addition tert-butanesulfinyl imines allyltrimethylsilane tetra-n-butylammonium fluoride.

Crystal and Molecular Structure of 2,3,5,6-Bis(ortho-1,10-decylidene)dihydropyrazine

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Chinese Journal of Structural Chemistry 2005年第11期24卷 1254-1258页

作者： WANG Ming-An ZHANG Ning hou xue-Tai WANG Dao-Quan Department of Applied Chemistry China Agricultural University Beijing 100094 China

The SnCl2 reduction of 2-nitrocyclododecanone or 2-bromo-12-nitrocyclododecanone gave a colorless compound 2,3,5,6-bis（ortho-1,10-decylidene）dihydropyrazine 1a characterized by IR, NMR and X-ray diffraction analysis. Crystal data for 1a： Mr = 358.60, monoclinic, space group P2 1/n, α = 0.48028（3）, b = 2.8646（4）, c = 0.77097（6） nm, β = 98.432（12）°, V = 1.04924（19） nm^3, Dc = 1.135 g/cm^3, Z = 2, F（000） = 400 and μ（MoKa） = 0.065 mm^-1. All ^1H- and ^13C-NMR resonance lines of 1a were assigned by DEPT, COSY, HMQC and HMBC technology. In the crystal, the dihydropyrazine ring has a planar structure, two twelve-membered tings adopt [lene2333] conformation, their double bonds have cis-configuration, and the whole molecule has a center of symmetry. In solution, the symmetric ^1H- and ^13C-NMR signals suggest that two twelve-membered rings of 1a may adopt enantiomorphous [ lene2333] conformation existing in a dynamic equilibrium.

关键词： 2,3,5,6-bis(ortho-1,10-decylidene)dihydropyrazine crystal structure NMR

Oxygen content and magnetic properties of composites La_(0.75)Sr_(0.25)MnO_(3±δ) dcalcined at different temperatures

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Rare Metals 2014年第4期33卷 452-458页

作者： Deng-Hui Ji xue hou Gui-De Tang Zhuang-Zhi Li Deng-Lu hou Ming-Gang Zhu Hebei Advanced Thin Films Laboratory Department of PhysicsHebei Normal University Division of Functional Materials Research Central Iron & Steel Research Institute

The effects of the calcination temperature on the oxygen content and magnetic properties of the nano- crystalline perovskite manganite Lao.75Sro.25MnO3±δ pre- pared by the sol-gel method were investigated. The highest temperatures at which the samples were calcined were 973, 1073, 1273, and 1473 K. The X-ray diffraction （XRD） analyses indicate that all the samples have only a single phase with the R3c perovskite structure. As the calcination temperature and calcination time increase, the oxygen content in the samples increases from being deficient to being in excess of that in the stoichiometric formula. The crystallite size also increases from 23 to 283 nm. Magnetic measurements indicate that the sample calcined at 1073 K has the highest Curie temperature. This is owing to the fact that the crystallite cores of this sample have stoichiometric oxygen content. The dependence of the Curie temperature and the saturation magnetization on the calcination tem- perature are successfully explained.

关键词： Perovskite manganite Magnetic property Oxygen content Sol-gel method

A New HPLC Method to Determine Carbonyl Compounds in Air

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Chinese Chemical Letters 2002年第12期13卷 1199-1202页

作者： Qing Tao PENG Wen Xiang HU xue Jun hou Institute of Military Medicine Headquarters of General EquipmentBeijing 100101

In this paper, a new HPLC method was established to determine the carbonyl compounds in air. As the absorbent, 2, 4-dinitrophenylhydrazine (2, 4-DNPH) reacted with carbonyls specifically, which form the corresponding 2,4-dinitrophenylhydrazones, then analyzed by HPLC. The chromatographic conditions, the recovery rate, stability of samples, reagent blank, sampling efficiency were all studied systematically. The results showed that this established method had high sensitivity and good selectivity compared with other analytical methods, and it can determine ten carbonyl compounds in air in 26 min simultaneously.

关键词： Carbonyl compounds HPLC 2,4-dinitrophenylhydrazine.

Enhancement of Mechanical Properties of Natural Rubber with Maleic Anhydride Grafted Liquid Polybutadiene Functionalized Graphene Oxide

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Chinese Journal of Polymer Science 2015年第7期33卷 1058-1068页

作者： Long-mei Wu 廖双泉 Sheng-jun Zhang Xiao-ying Bai xue hou College of Agriculture Hainan University College of Materials and Chemical Engineering Hainan University

An effective procedure has been developed to synthesize the functionalized graphene oxide grafted by maleic anhydride grafted liquid polybutadiene（MLPB-GO）. Fourier transform spectroscopy and X-ray photoelectron spectroscopy indicate the successful functionalization of GO. The NR/MLPB-GO composites were then prepared by the co-coagulation process. The results show that the mechanical properties of NR/MLPB-GO composites are obviously superior to those of NR/GO composites and neat NR. Compared with neat NR, the tensile strength, modulus at 300% strain and tear strength of NR composite containing 2.12 phr MLPB-GO are significantly increased by 40.5%, 109.1% and 85.0%, respectively. Dynamic mechanical analysis results show that 84% increase in storage modulus and 2.9 K enhancement in the glass transition temperature of the composite have been achieved with the incorporation of 2.12 phr MLPB-GO into NR. The good dispersion of GO and the strong interface interaction in the composites are responsible for the unprecedented reinforcing efficiency of MLPB-GO towards NR.

关键词： Enhancement Maleic anhydride-grafted liquid polybutadiene Graphene oxide Composites Mechanical properties

Osthole prevents cognitive impairment through modulating neuron cells in Aβ25-35-injected mice

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中国药理学与毒理学杂志 2019年第6期33卷 417-418页

作者： hou xue-qin Institute of Pharmacology Shandong First Medical University & Shang dong Academy of Medical Sciences

OBJECTIVE To investigate the effects of osthole on learning and memory impairment of AD mice induced by injection of Aβ25-35 and the content of Ca2+, GLU and Aβ1-42 in the brain tissue and peripheral blood. METHODS Mice were randomly assigned to sham operation, Aβ25-35, Aβ25-35+Ost-L,Aβ25-35+Ost-M, and Aβ25-35+Ost-H group. Water maze test was performed to assessing spatial learning ability of mice. It is determined that the MDA level and the activity of SOD in the brain tissue of mice in each group by colorimetry. The GLU kit and Ca2 +kit were used to detect the GLU, Ca2 +in tissue and serum. ELISA was used to detect the expression of Aβ1-42 in the hippocampus and serum of mice. HE staining and silver staining were used to detect neuron apoptosis and pathological changes in brain slices and so on. RESULTS(1) Effects of osthole on learning and memory: With the increase of training day,the escape latencies continuously reduced in each experimental group, the escape latencies of the model group was longer on the 1 st, 2 nd, 3 rd, and 5 thdays than the normal group, the difference was statistically significant(day 3 and 4: P<0.05, day 5: P<0.01);compared with the model group, the escaping latency on the 5 thday of the OST low-medium high-dose group was significantly shortened, which was statistically significant(P<0.05).(2) Effects on oxidative stresspathway: the SOD activity of AD mice in the hippocampus model group was lower than that in the normal group, which was statistically significant(P<0.05);The SOD activity in the OST group was higher than that in the model group, which was statistically significant(P<0.05). The MDA content in the model group was significantly higher than that in the normal group(P<0.05). The MDA content in the OST high-dose group was lower than that in the model group, which was statistically significant(P<0.05).(3) Effects of GLU levels on neurotransmitters:the results of the detection of GLU in cortical area and GLU in serum of AD mice in O

关键词： osthole Alzheimer disease Aβ25-35 spatial learning and memory

Submicron single-crystalline LiNi_(0.5)Mn_(1.5)O_(4) cathode with modulated Mn^(3+) content enabling high capacity and fast lithium-ion kinetics

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Rare Metals 2022年第7期41卷 2268-2279页

作者： Zhao Fang Xing-Liang Zhang xue-Yang hou Wen-Long Huang Lin-Bo Li School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Research Center of Metallurgical Engineering and Technology of Shaanxi Province Xi’an 710055China

Disordered single-crystalline LiNi_(0.5)Mn_(1.5)O_(4)(LNMO)cathode materials with different Mn^(3+)contents were prepared by a simple temperature control strategy of a solid-state *** effects of the mutual modulation of the Mn^(3+) content and the bulk microstructure on the crystal structure and electrochemical properties of LNMO were systematically *** showed that a suitable Mn^(3+) content can enhance the structural stability and alleviate structural degradation and capacity *** excellent performance originates from the simultane-ous inhibition of microcrack formation and side reaction with electrolytes,ensuring the rapid diffusion of Li+during extraction and ***,the LNMO-800 sample delivers an excellent cycling stability with a capacity retention of 98.37%after 200 cycles,remarkable rate capacity of 115 mAh·g^(-1) at 10.0C,and rapid Li+diffusion coefficient of 4.43×10^(-9)cm^(2)·s^(-1).This work will allow for a deeper understanding of the coupling effect between Mn^(3+)content and bulk microstructure,especially in the design and development of Mn-based cathode materials.

关键词： microstructure cycling content

Advances in electrical impedance tomography-based brain imaging

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Military Medical Research 2022年第6期9卷 705-726页

作者： Xi-Yang Ke Wei hou Qi Huang xue hou xue-Ying Bao Wei-Xuan Kong Cheng-Xiang Li Yu-Qi Qiu Si-Yi Hu Li-Hua Dong Department of Radiation Oncology and Therapy the First Hospital of Jilin UniversityChangchun 130021China Jilin Provincial Key Laboratory of Radiation Oncology and Therapy the First Hospital of Jilin UniversityChangchun 130021China NHC Key Laboratory of Radiobiology School of Public HealthJilin UniversityChangchun 130021China CAS Key Laboratory of Bio-Medical Diagnostics Suzhou Institute of Biomedical Engineering and TechnologyChinese Academy of SciencesSuzhou 215163JiangsuChina

Novel advances in the field of brain imaging have enabled the unprecedented clinical application of various imaging modalities to facilitate disease diagnosis and treatment. Electrical impedance tomography(EIT) is a functional imaging technique that measures the transfer impedances between electrodes on the body surface to estimate the spatial distribution of electrical properties of tissues. EIT offers many advantages over other neuroimaging technologies,which has led to its potential clinical use. This qualitative review provides an overview of the basic principles,algorithms, and system composition of EIT. Recent advances in the field of EIT are discussed in the context of epilepsy,stroke, brain injuries and edema, and other brain diseases. Further, we summarize factors limiting the development of brain EIT and highlight prospects for the field. In epilepsy imaging, there have been advances in EIT imaging depth,from cortical to subcortical regions. In stroke research, a bedside EIT stroke monitoring system has been developed for clinical practice, and data support the role of EIT in multi-modal imaging for diagnosing stroke. Additionally, EIT has been applied to monitor the changes in brain water content associated with cerebral edema, enabling the early identification of brain edema and the evaluation of mannitol dehydration. However, anatomically realistic geometry,inhomogeneity, cranium completeness, anisotropy and skull type, etc., must be considered to improve the accuracy of EIT modeling. Thus, the further establishment of EIT as a mature and routine diagnostic technique will necessitate the accumulation of more supporting evidence.

关键词： Electrical impedance tomography(EIT) Brain diseases Tissue impedance Microelectrode array

Isomerization of 4-Amino-6-tert-butyl-3-methylthio-1,2,4-triazin-5(4H)-one with Base

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Chinese Chemical Letters 2001年第9期12卷 753-756页

作者： Hong Chao GUO Shang Zhong LIU xue Tai hou Min WANG Department of Applied Chemistry China Agricultural UniversityBeijing 100094

Isomerizaton of 4-amino-6-tert-butyl-3-methylthio-1, 2, 4-triazin-5 (4H)-one in the presence of base is described. Mechanism of this rearrangement reaction involving four-member ring intermediate formation has been pr... 详细信息

关键词： Isomerization base metribuzin