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Characterizations of Centralizable Mappings on Algebras of Locally Measurable Operators

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Acta Mathematica Sinica,English Series 2020年第9期36卷 1039-1048页

作者： Jun HE Guang Yu AN Jian kui li Wen Hua QIAN Department of Mathematics Anhui Polytechnic UniversityWuhu 241000P.R.China Department of Mathematics Shaanxi University of Science and TechnologyXi'an 710021P.R.China Department of Mathematics East China University of Science and TechnologyShanghai 200237P.R.China School of Mathematical Sciences Chongqing Normal UniversityChongqing 401331P.R.China

A linear mappingφfrom an algebra A into its bimodule M is called a centralizable mapping at G∈A ifφ(AB)=φ(A)B=Aφ(B)for each A and B in A with AB=*** this paper,we prove that if M is a von Neumann algebra without direct summands of type I1 and type II,A is a*-subalgebra with M■A■LS(M)and G is a fixed element in A,then every continuous(with respect to the local measure topology t(M))centralizable mapping at G from A into M is a centralizer.

关键词： Centralizable mapping centralizer von Neumann algebra locally measurable operator

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X射线辐照对彩色马铃薯贮藏保鲜效果的影响

食品工业科技 2024年第15期45卷 322-331页

作者：蔚江涛白俊青李奎牛伟康璐瑶寇莉萍王瑞瑶李世超王冬冬候德华陈勤杨凌核盛辐照技术有限公司陕西杨凌712100 西北农林科技大学食品科学与工程学院陕西杨凌712100 江苏彩薯农业科技有限公司江苏镇江212000

为探究不同剂量X射线辐照对彩色马铃薯发芽和贮藏品质的影响,本研究以彩色马铃薯黄玫瑰3号、紫玫瑰3号、红玫瑰5号和普通马铃薯为试验原料,采用0、100、300、500 Gy不同剂量的5 MeV电子束转靶X射线处理,将处理后的马铃薯贮藏于常温(20... 详细信息

为探究不同剂量X射线辐照对彩色马铃薯发芽和贮藏品质的影响,本研究以彩色马铃薯黄玫瑰3号、紫玫瑰3号、红玫瑰5号和普通马铃薯为试验原料,采用0、100、300、500 Gy不同剂量的5 MeV电子束转靶X射线处理,将处理后的马铃薯贮藏于常温(20±2)℃、相对湿度为80%~90%的条件下,分析贮藏期的发芽率、失重率、硬度、VC含量、干物质含量和呼吸强度的参数变化,研究X射线辐照处理对马铃薯外观品质、营养品质的影响及贮藏保鲜效果。结果表明:X射线辐照处理降低了马铃薯贮藏中后期的呼吸强度,延缓了贮藏过程中的失重、硬度下降及VC含量的损失,其中黄玫瑰3号、紫玫瑰3号、红玫瑰5号和普通马铃薯100 Gy辐照处理组与对照组相比,失重率分别降低12.76%、5.31%、6.05%和1.43%,贮藏末期相对贮藏初期硬度下降程度分别降低12.98%、6.40%、8.34%和7.13%,VC含量损失率分别降低17.71%、22.80%、13.52%和14.65%;4个品种马铃薯经过不同剂量X射线辐照处理后,贮藏至240 d以上均未出现发芽现象;100 Gy低剂量X射线辐照处理即可达到理想的抑芽效果,且延缓失重、硬度下降方面均优于300、500 Gy,可作为彩色马铃薯和普通马铃薯辐照保鲜工业应用的推荐工艺剂量。本研究工作为X射线辐照技术在彩色马铃薯贮藏保鲜中的应用提供了理论依据和技术指导。

关键词：彩色马铃薯 X 射线辐照抑芽贮藏保鲜

Enhanced transient photovoltaic characteristics of core–shell ZnSe/ZnS/L-Cys quantum-dot-sensitized TiO_2 thin-film

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Chinese Physics B 2018年第6期27卷 415-423页

作者： kui-Ying li Lun Ren Tong-De Shen State Key Laboratory of Metastable Materials Science ＆ Technology Yanshan University Qinhuangdao 066004 China

Photoanodic properties greatly determine the overall performance of quantum-dot-sensitized solar cells（QDSCs）. In the present report, the microdynamic behaviors of carriers in the nanocomposite thin-film, a Zn Se QD-sensitized mesoporous La-doped nano-TiO2 thin-film, as a potential candidate for photoanode, are probed via nanosecond transient photovoltaic（TPV） spectroscopy. The results confirm that the L-Cys ligand has a dual function serving as a stabilizer and molecular linker. Large quantities of interface states are located at the energy level with a photoelectric threshold of1.58 eV and a quantum well（QW） depth of 0.67 eV. This QW depth is approximately 0.14 eV deeper than the depth of QW buried in the Zn Se QDs, and a deeper QW results in a higher quantum confinement energy. A strong quantum confinement effect of the interface state may be responsible for the excellent TPV characteristics of the photoanode. For example, the peak intensity of the TPV response of the QD-sensitized thin-film lasts a long time, from 9.40 × 10^（-7） s to 2.96 × 10^（-4） s,and the end time of the PTV response of the QD-sensitized thin-film is extended by approximately an order of magnitude compared with those of the TiO2 substrate and the QDs. The TPV characteristics of the QD-sensitized thin-film change from p-type to n-type for the QDs before and after sensitizing. These properties strongly depend on the extended diffusion length of the photogenerated carries and the reduced recombination rate of photogenerated electron-hole pairs, resulting in prolonged carrier lifetime and an increased level of electron injection into the TiO2 thin-film substrate.

关键词： sensitization core-shell ZnSe quantum dots mesoporous Ti02 thin-film time-resolution photo- voltage

超声检查脐动脉血流参数及孕妇血清sFlt-1、PP13水平对胎儿生长受限的诊断价值分析

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黑龙江医药科学 2024年第4期47卷 67-71页

作者：李娟常茹晗王辉闫红杰李葵郑州四六〇医院超声医学科河南郑州450000 郑州人民医院超声医学科河南郑州450000

目的:探讨超声检查脐动脉血流参数、孕妇血清可溶性酪氨酸激酶-1(sFlt-1)、胎盘蛋白13(PP13)水平对胎儿生长受限(FGR)的诊断价值。方法:回顾性选取2022年1月至2023年7月于郑州四六〇医院产检并确诊的186例FGR孕妇作为观察组,另匹配同期6... 详细信息

目的:探讨超声检查脐动脉血流参数、孕妇血清可溶性酪氨酸激酶-1(sFlt-1)、胎盘蛋白13(PP13)水平对胎儿生长受限(FGR)的诊断价值。方法:回顾性选取2022年1月至2023年7月于郑州四六〇医院产检并确诊的186例FGR孕妇作为观察组,另匹配同期62例正常孕妇作为对照组。比较两组脐动脉血流参数[搏动指数(PI)、阻力指数(RI)、收缩期最大血流速度/舒张末期血流速度(S/D)]及血清sFlt-1、PP13水平。统计两组临床资料,并分析FGR发病影响因素。分析脐动脉血流参数、血清sFlt-1、PP13水平与FGR严重程度指标相关性。受试者工作特征曲线(ROC)及曲线下面积(AUC)分析脐动脉血流参数、血清sFlt-1、PP13对FGR的诊断价值。采用决策曲线(DCA)评价各指标联合诊断模型临床获益。结果:观察组PI、RI、S/D及血清sFlt-1水平高于对照组,血清PP13水平低于对照组(P<0.05);羊水过少、不良妊娠史、胎盘/脐带异常及PI、RI、S/D、sFlt-1为FGR发生的独立危险因素,胎盘质量、新生儿出生体质量、1min Apagar评分、PP13为FGR发生的独立保护因素(P<0.05);PI、RI、S/D、sFlt-1与胎盘质量、新生儿出生体质量、1min Apagar评分呈负相关,而与PP13呈正相关(P<0.05);脐动脉血流参数、血清sFlt-1、sFlt-1联合诊断FGR的AUC大于单项指标诊断(P<0.05),且DCA分析证实联合检测时临床净受益率优于单项指标检测。结论:FGR孕妇PI、RI、S/D及血清sFlt-1水平升高,PP13水平降低,且为FGR发生的独立影响因素,联合检测其水平对FGR发生具有一定诊断价值。

关键词：胎儿生长受限脐动脉血流可溶性酪氨酸激酶-1 胎盘蛋白13 超声诊断

High-performance oxygen permeation membranes:Cobalt-free Ba_(0.975)La_(0.025)Fe_(1-x)Cu_(x)O_(3)-δceramics

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Journal of Materiomics 2019年第2期5卷 264-272页

作者： Zilu liu kui li Hailei Zhao Konrad Swierczek School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Beijing Municipal Key Lab for Advanced Energy Materials and Technologies Beijing 100083China AGH University of Science and Technology Faculty of Energy and Fuelsal.A.Mickiewicza 3030-059 KrakowPoland AGH Centre of Energy AGH University of Science and Technologyul.Czarnowiejska 3630-054 KrakowPoland

A new group of cobalt-free perovskite oxides,Ba_(0.975)La_(0.025)Fe_(1-x)Cu_(x)O_(3-δ)(BLFC,x=0.05-0.15),was designed,characterized and applied as oxygen permeation *** was found that BLFC oxides with Cu doping range of 0.075-0.15 maintain cubic perovskite phase in a wide range of *** Cu introduced at the B-site results in a gradual increase of the electrical conductivity,which is attributed to the denser overlapping of electron clouds of CueO *** increasing Cu content,the oxygen vacancy concentration increases and the oxygen ion migration energy decreases,leading to the highest oxygen permeation flux of 1.59 mL cm^(-2)min^(-1)recorded for Ba_(0.975)La_(0.025)Fe_(0.9)Cu_(0.1)O_(3-δ)1mm thick membrane at 950℃.However,the oxygen permeability decreases with further Cu doping,which may be correspond to a presence of defect ***_(0.975)La_(0.025)Fe_(0.9)Cu_(0.10)O_(3-δ)membrane with 0.7mm thickness delivers stable oxygen permeation flux of 1.57 mL cm^(-2)min^(-1)for 200 h at 900℃.All of the obtained results indicate that the developed BLFC with optimized Cu content(i.e.x=0.1)is a very promising material for usage in oxygen separation applications.

关键词： Perovskite Oxygen permeability Structure stability Oxygen ion migration

Micro-segregation and Precipitation of Alloy 690 during Isothermal Solidification:the Role of Nitrogen Content

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Journal of Materials Science & Technology 2012年第5期28卷 446-452页

作者： Rong Jiang Bo Chen Xianchao Hao Yingche Ma Shuo li kui liu Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

The segregation and precipitation behavior of Alloy 690 containing 0.001-0.11 wt% nitrogen during isothermal solidification at 1370 and 1355 ℃ have been investigated using optical microscopy （OM）,electron probe microanalysis （EPMA） and transmission electron microscopy （TEM）.The results indicate that the volume fraction of TiN-type nitride formed during isothermal solidification increases with the nitrogen content of Alloy *** of Ti and Cr exists in samples solidified at 1370 and 1355℃.The Ti content in the residual liquid markedly decreases and the concentration of Cr increases when the nitrogen content of Alloy 690 ***,N and S also show segregation to some extent in the residual liquids at 1355℃.Accompanying by the segregation of Cr,Ti,C,N and S,sulfides and chromium nitrides *** a low nitrogen content Alloy 690,sulfur segregates and precipitates in the form of Ti 4 C 2 S 2 and （Cr,Ti）S,but in the form of （Cr,Ti）S or CrS in a high nitrogen content Alloy 690.（Cr,Ti）N-type nitrides with an fcc crystal structure have been identified in a sample with 0.11 wt% nitrogen.

关键词： Alloy 690 Nitrogen content Solidification Micro-segregation Precipitate

Evaluation of the vaginal microbiome in clinical diagnosis and management of vaginal infectious diseases

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Chinese Medical Journal 2019年第9期132卷 1100-1103页

作者： Ting li Zhao-Hui liu kui li Hui-Hui Bai Department of Gynecology Beijing Obstetrics and Gynecology HospitalCapital Medical UniversityBeijing 100026China Department of Obstetrics and Gynecology Beijing United Family HealthcareBeijing 100015China Department of Microecological Laboratory Beijing Obstetrics and Gynecology HospitalCapital Medical UniversityBeijing 100026China

When patients attend with medical complaints such as abnormal leucorrhea,the clinician should consider the possibility of an infection in the lower genital tract,such as vulvovaginal candidiasis (WC).At that point,it is appropriate to then further assess the typical clinical manifestation,diagnosis,and routine management of the ***,sometimes,it is not possible to detect any pathogen at all through standard diagnostic *** such a scenario,what happens to these patients?

关键词： patients complaints leucorrhea

Recent development of methanol electrooxidation catalysts for directmethanol fuel cell

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Journal of Energy Chemistry 2018年第6期27卷 1618-1628页

作者： liyuan Gong Zhiyuan Yang kui li Wei Xing Changpeng liu Junjie Ge State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 jilinChina University of Chinese Academy of Sciences Beijing 100039 China Laboratory of Advanced Power Sources Changchun Institute of Applied Chemistry Chinese Academy of Sdences Changchun 130022 Jilin China Jilin Province Key Laboratory of Low Carbon Chemical Power Sources Changchun 130022 Jilin China

Direct methanol fuel cells （DMFCs） are very promising power source for stationary and portable miniatureelectric appliances due to its high efficiency and low emissions of pollutants. As the key material, cata-lysts for both cathode and anode face several problems which hinder the commercialization of *** this review, we mainly focus on anode catalysts of DMFCs. The process and mechanism of methanolelectrooxidation on Pt and Pt-based catalysts in acidic medium have been introduced. The influences ofsize effect and morphology on electrocatalytic activity are discussed though whether there is a size effectin MOP, catalyst is under debate. Besides, the non Pt catalysts are also listed to emphasize though Pt isstill deemed as the indispensable element in anode catalyst of DMFCs in acidic medium. Different cata-lyst systems are compared to illustrate the level of research at present. ome debates need to be verifiedwith experimental evidences.

关键词： DMFCs Methanol electrooxidation Anode catalysts

Microstructure and mechanical properties of a Cr-Ni-W-Mo steel processedthermo-mechanical controlled processing

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Journal of Iron and Steel Research International 2021年第6期28卷 713-721页

作者： Jia-xin liang Ying-chun Wang Xing-wang Cheng Zhuang li Jin-ke Du Shu-kui li School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China National Key Laboratory of Science and Technology on Materials Under Shock and Impact Beijing 100081China

Experiments were conducted to evaluate the microstructure and tensile properties of a medium carbon Cr-Ni-W-Mo steel processedthermo-mechanical controlled processing(TMCP)with cooling at different conditions in water,oil,air or lime followedlow *** to normal heat-treatment processing,TMCP with water-cooling after deformation enhances the yield strength and tensile strength of the steelabout 323 MPa and about 251 MPa,respectively,due to higher dislocation strengthening and grain boundary ***,it increases the elongation by ;about 1.76%attributed to the increase in volume percentage of the retained austenite and the refined laths of tempered *** the cooling rate after deformation during TMCP leads to a decrease in the *** results the coupling effectsthe reduction in dislocation density and volume fraction of tempered martensite together with the coarseness in martensite ***,cooling rate decreasing has less influences on ductility becathe improved elongation the increase in the volume fractions of both retained austenite and lower bainite together with dislocation density decreasing is compensatedthe reduced elongation coarsened grains.

关键词： Thermo-mechanical controlled processing Ultra-high strength steel Microstructure Bainite Tensile property