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基于变精度粗糙集的多属性群决策信息系统安全评估

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上海交通大学学报 2009年第7期43卷 1161-1166页

作者：赵亮薛质上海交通大学电子信息与电气工程学院上海200240

为了获取信息系统安全状况并制定相应的安全解决方案,提出了基于变精度粗糙集(VPRS)的多属性群决策安全评估方法.以某高校校园网络系统作为评估样本,在信息系统安全评估模型的基础上,将VPRS与层次分析法(AHP)相结合,利用VPRS分类质量的... 详细信息

为了获取信息系统安全状况并制定相应的安全解决方案,提出了基于变精度粗糙集(VPRS)的多属性群决策安全评估方法.以某高校校园网络系统作为评估样本,在信息系统安全评估模型的基础上,将VPRS与层次分析法(AHP)相结合,利用VPRS分类质量的概念,挖掘出隐含在数据背后的内在规律.在确定安全属性权重的基础上,对信息系统进行综合安全评估.实例证明,该方法可以有效解决多属性群决策的瓶颈问题,在信息系统安全评估中具有实际意义.

关键词：安全评估信息系统多属性群决策变精度粗糙集

Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai Zhang Pei-zhi Liu Yan-Bo Li Qi Zhang Jun-zhao Xiao Yi-Fan Wang Tian-Yu Wei Jia-Wei Jiang Ye Wang Qian Peng liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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全谷物及杂豆添加量在小鼠与人体间剂量换算分析

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食品科学 2025年第2期46卷 118-125页

作者：支莉朱益清赵亮星陈睿赵卿宇王超薛勇沈群国家粮食产业(青稞深加工)技术创新中心国家粮油标准测试研究中心中国农业大学食品科学与营养工程学院北京100083

适量摄入全谷物及杂豆可以改善糖代谢和脂代谢,但摄入量过高可能产生不利影响。由于缺乏相应的换算关系,小鼠饲料中的摄入量无法直接作为人群摄入量的参考。本文介绍小鼠饲料中常见的全谷物及杂豆的添加量,并通过等效系数法、比表面积... 详细信息

适量摄入全谷物及杂豆可以改善糖代谢和脂代谢,但摄入量过高可能产生不利影响。由于缺乏相应的换算关系,小鼠饲料中的摄入量无法直接作为人群摄入量的参考。本文介绍小鼠饲料中常见的全谷物及杂豆的添加量,并通过等效系数法、比表面积法、体型系数法、食物比重法、体表面积指数法、能量换算法和营养素换算法探讨了小鼠饲料中全谷物及杂豆添加量与人群膳食推荐量之间的剂量效应关系。研究表明,当人群全谷物及杂豆推荐摄入量为50~150 g时,相当于在每日进食量为3 g的小鼠饲料中添加5%~50%的全谷物及杂豆。对于小鼠而言,饲料中全谷物及杂豆的添加量超过50%可能存在过量摄入的风险。本研究为未来建立全谷物及杂豆在小鼠饲料添加量与人群推荐摄入量之间的换算关系提供了重要参考。

关键词：剂量换算全谷物杂豆体表面积

Landfill leachate production, quality and recirculation treatment in northeast China

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Journal of Environmental Sciences 2006年第4期18卷 625-628页

作者： zhao Qing-liang LIU xue-yan QI Xu-dong LIU zhi-gang School of Municipal and Environment Engineering Harbin Institute of Technology Harbin 150090 China

Landfill leachate recirculation treatment process is a promising and economic way in northeast China due to the distinct season variation. In order to study the impact of recirculation on leachate production and its quality, two simulated sanitary landfill reactors, one with leachate recirculation and the other without, were placed outdoor in Harbin. The two-year experimental results indicated that leachate production was reduced by 86% with leachate recirculation and less or no facility for leachate treatment required. Recirculation could improve the leachate quality dramatically with lower COD, SS, NF4-N and higher pH level. Recirculation also could enhance waste degradation and stabilization and improve the efficiency of landfill. This study confirmed that leachate recirculation was a very feasible way for on-site landfill leachate treatment in cold areas.

关键词： cold area sanitary landfill leachate recirculation solid waste

Effects of temperature-gradient-induced damage of zirconia metering nozzles

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International Journal of Minerals,Metallurgy and Materials 2017年第9期24卷 999-1003页

作者： liang zhao Qun-hu xue College of Materials and Mineral Resources Xi’an University of Architecture and TechnologyXi’an 710055China Shaanxi Techno-institute of Recycling Economy Xi’an 710055China

The effects of temperature-gradient-induced damage of zirconia metering nozzles were investigated through analysis of the phase composition and microstructure of nozzle samples. The analysis was carried out using X-ray diffraction and scanning electron microscopy after the samples were subjected to a heat treatment based on the temperatures of the affected, transition, and original layers of zirconia metering nozzles during the continuous casting of steel. The results showed that, after heat treatment at 1540, 1410, or 1300A degrees C for a dwell time of 5 h, the monoclinic zirconia phase was gradually stabilized with increasing heat-treatment temperature. Moreover, a transformation to the cubic zirconia phase occurred, accompanied by grain growth, which illustrates that the temperature gradient in zirconia metering nozzles affects the mineral composition and microstructure of the nozzles and accelerates damage, thereby deteriorating the quality and service life of the nozzles.

关键词： temperature gradient zirconia metering nozzles mineral composition microstructure damage mechanism

Microstructure, property and deformation and fracture behavior of 800 MPa complex phase steel with different coiling temperatures

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Journal of Iron and Steel Research International 2021年第3期28卷 346-359页

作者： Jian-zhong xue Zheng-zhi zhao Di Tang Hui Li Hao-hong Wu Wei-liang Xiong liang liang Yao Huang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation Beijing100083China VALIN LY STEEL Co. Ltd.Loudi417000HunanChina China Electric Power Research Institute Beijing100085China

The microstructure characteristics and properties(especially hole expansion property)of 800 MPa hot-rolled complex phase steel with different coiling temperatures were *** microstructure consisted of polygonal ferrite and precipitates when the steel was coiled at 550℃,and when the steel was coiled between 460–520℃,the microstructure was composed of granular bainite and martensite and austenite(M/A)*** morphology of the crack was analyzed by scanning electron microscopy,and the in situ scanning electron microscope tensile test was used to find out the fracture mechanism and deformation behavior of the steel with different coiling *** the steel was coiled at 550℃,the cracks initiated at the ferrite grain boundary and propagated through the grains or along the grain *** the steel was coiled at 520℃,the cracks first initiated at the junction of ferrite and M/A island and then propagated through the *** steel coiled at 520℃ has quite good mechanical properties and relatively high hole expansion ratio.

关键词： Complex phase steel Coiling temperature Strength In situ tensile test Hole expansion ratio Crack

Pentanuclear Gold(Ⅰ) Cluster with an Axially Chiral Biaryl Center:Synthesis and Chiral Transformation

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Chinese Journal of Chemistry 2019年第7期37卷 667-671页

作者： Yang xue liang zhao The Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua University Beijing 100084 China

We synthesized and structurally characterized a novel pentanuclear gold(I) cluster by a Ag(Ⅰ)-mediated organometallic *** racemic mixture of this pentanuclear gold cluster has been successfully transformed into an enantio-rich hexanuclear cluster compound by adding adscititious chiral species [Au2(S-BINAP)2]2+(S-BINAP =(S)-2,2'-bis(diphenylphosphino)-1,1'-binaphthyl).In this process,a [AuPPh3]+ species in the pentanuclear cluster is replaced by [Au2(S-BINAP)2]2+.This strategy represents a new method for the designed construction of chiral metal clusters.

关键词： Cluster cluster has

Some properties of the psi function and evaluations of γ

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Applied Mathematics(A Journal of Chinese Universities) 2016年第1期31卷 103-111页

作者： QIU Song-liang zhao xue School of Science Zhejiang Sci-Tech University

In this paper, the authors show some monotonicity and concavity of the classical psi function, by which several known results are improved and some new asymptotically sharp estimates are obtained for this function. In addition, applying the new results to the psi function, the authors improve the well-known lower and upper bounds for the approximate evaluation of Euler＇s constant γ.

关键词： Psi function gamma function monotonicity concavity inequality Euler's constant.

Removal and transformation of dissolved organic matter in secondary effluent during granular activated carbon treatment

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第7期9卷 994-1003页

作者： liang-liang WEI Qing-liang zhao Shuang xue Ting JIA State Key Laboratory of Urban Water Resources and Environments （SKL UWRE） School of Municipal and Environmental Engineering Harbin Institute of Technology Harbin 150090 China

This paper focused on the removal and transformation of the dissolved organic matter （DOM） in secondary effluent during the granular activated carbon （GAC） treatment. Using XAD-8/XAD-4 resins, DOM was fractionated into five classes： hydrophobic acid （HPO-A）, hydrophobic neutral （HPO-N）, transphilic acid （TPI-A）, transphilic neutral （TPI-N） and hydrophilic fraction （HPI）. Subsequently, the water quality parameters of dissolved organic carbon （DOC）, absorbance of ultraviolet light at 254 nm （UV-254）, specific ultraviolet light absorbance （SUVA） and trihalomethane formation potential （THMFP） were analyzed for the unfractionated and fractionated water samples. The results showed that the order of the DOC removal with respect to DOM fractions was observed to be HPI〉HPO-A〉HPO-N〉TPI-A〉TPI-N. During the GAC treatment, the THMFP of the unfractionated water samples decreased from 397.4 μg/L to 176.5 μg/L, resulting in a removal efficiency of 55.6%. The removal order of the trilaalomethanes （THMs） precursor was as follows： HPO-A〉TPI-A〉TPI-N〉HPO-N〉HPI. By the GAC treatment, the specific THMFP of HPO-A, TPI-A, TPI-N and the original unfractionated water samples had a noticeable decrease, while that of HPO-N and HPI showed a converse trend. The Fourier transform infrared （FTIR） results showed that the hydroxide groups, carboxylic acids, aliphatic C-H were significantly reduced by GAC treatment.

关键词： Dissolved organic matter (DOM) Fractionation Trihalomethane formation potential (THMFP) Specific THMFP Fourier-transform infrared (FTIR)