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Effect of Surfactant/Silica and Hydrothermal Time on the Specific Surface Area of Mesoporous Materials from Coal-Measure Kaolin

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Journal of Wuhan University of Technology(Materials Science) 2011年第3期26卷 514-518页

作者：吴其胜 School of Materials Engineering Yancheng Institute of Technology

Mesoporous materials with the highest surface area were synthesized by hydrothermal treatment from coal-measure kaolin using cetyltrimethylammonium bromide（CTAB）as *** effect of several factors on surface area of products also had been *** products were characterized by FT- IR,HRTEM and N 2 adsorption and desorption isotherm plot *** was typical structure as Si-O,Si- OH and Si-O-Si of mesoporous materials in the framework of synthesized materials;the pore size distributions of the products showed a sharp peak at 3.82 *** effect of hydrothermal treatment time and the amount of template on the specific surface area of mesoporous materials was important,when the Surf/Si=0.135,and hydrothermal time=12 h,and the surface area of the product reached up to 1 070 m2/g,which was higher than other products.

关键词： coal-measure kaolin mesoporous materials hydrothermal synthesis

A Theory of Isomorphisms of Fuzzy Groups

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模糊系统与数学 1988年第2期 57-68页

作者： Yu Yandong(Dept. Math., yancheng teachers college, Jiangsu, china)

In this paper, a theory of isomorphisms of fuzzy groups is put forward. First, a new definition of isomorphisms of fuzzy groups is proposed and compared with the corresponding ones given in other related papers. Next, some basic properties of this kind of isomorphisms are roughly examined. Then, as the main results of this paper, two basic isomorphism theorems for fuzzy groups are establised. Finally, presenting applications of these theorems, we point out that for any given t-norm T∈■ss∪■H∪■F∪■Y)/{Min}, every T-fuzzy group is isomorphic to a Prod-fuzzy or Tm-fuzzy group, where ■ss, ■H, ■F and ■Y denote the Schweizer-Sklar, Hamacher, Frank and Yager families of t-norms, respectively.

关键词： Fuzzy group λ-isomorpbism pre-isomorphism isomorphism basic isomorphisms theorem for fuzzy groups.

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经济全球化时期高校图书馆如何勇立潮头

图书馆论坛 2002年第4期22卷 114-115页

作者：洪丽盐城师范学院图书馆江苏盐城224002

进入经济全球化的新时期 ,高校图书馆只有尽快建立市场竞争机制、服务运行机制、现代化管理机制、有偿经营机制 ,才能勇立潮头。

关键词：高校图书馆经济全球化机制改革

Images on Locally Separable Metric Spaces

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Acta Mathematica Sinica,English Series 1997年第1期13卷 1-8页

作者： Lin Shou (department of mathematics,Ningde teachers’ college,Fujian 352100,china)Liu Chuan Dai Mumin (department of mathematics,Guangxi University,Nanning 530004,china) 宁德师范高等专科学校数学系福建宁德广西大学数学系广西南宁

In this paper internal characterizations on certain quotient images of locally separable metric spaces are *** obtain some descriptions of quotient s-images,pseudo-open s- images,quotient compact images and closed images of locally separable metric spaces,and establish some relations between these and certain quotient images of metric spaces by the local separability of suitable subspaces.

关键词： Locally separable Metric space Quotient mapping Pseudo-open mapping Closed mapping cs-network k-network.

Affine formation maneuver tracking control of multiple second-order agents with time-varying delays

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Science china(Technological Sciences) 2019年第4期62卷 665-676页

作者： XU Yang LI DongYu LUO DeLin YOU yancheng School of Aerospace Engineering Xiamen University department of Electrical and Computer Engineering National University of Singapore department of Control Science and Engineering Harbin Institute of Technology

This paper considers an affine maneuver tracking control problem for leader-follower type second-order multi-agent systems in the presence of time-varying delays, where the interaction topology is directed. Using the property of the affine transformation,this paper gives the sufficient and necessary conditions of achieving the affine localizability and extends it to the second-order condition. Under the(n + 1)-reachable condition of the given n-dimensional nominal formation with n + 1 leaders, a formation of agents can be reshaped in arbitrary dimension by only controlling these leaders. When the neighboring positions and velocities are available, a formation maneuver tracking control protocol with time-varying delays is constructed with the form of linear systems, where the tracking errors of the followers can be specified. Based on Lyapunov-Krasovskii stability theory, sufficient conditions to realize affine maneuvers are proposed and proved, and the unknown control gain matrix can be solved only by four linear matrix inequalities independent of the number of agents. Finally, corresponding simulations are carried out to verify the theoretical results, which show that these followers can track the time-varying references accurately and continuously.

关键词： formation control affine transformation multi-agent systems second-order dynamics time-varying delays

ARC-TRANSITIVE CUBIC GRAPHS OF ORDER 4_p

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Chinese Annals of mathematics,Series B 2004年第4期25卷 545-554页

作者： XUMINGYAO ZHANGQINHAI ZHOUJINXIN SchoolofmathematicsandComputerSciences ShanxiTeachersUniversityLinfen041004ShanxiChina SchoolofmathematicsandComputerSciences ShanxiTeachersUniversityLinfen041004ShanxiChina.

In this paper, a complete classification of arc-transitive cubic graphs of order 4p is given.

关键词： Arc-transitive graph Cubic s-regular graph Coverings of a graph

C-Wellposedness of the Complete Second Order Abstract Cauchy Problem and Applications

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Acta Mathematica Sinica,English Series 1999年第4期15卷 535-548页

作者： Mingchu Gao department of mathematics,Shanxi teachers University,Linfen 041004,P.R.china E-mail:mcgao@*** department of mathematics Shanxi Teachers University Linfen P. R. China

In this paper,we first give a sufficient and necessary condition for M= to generate an exponentially bounded =-semigroup and discuss its relations to the C-wellposedness of the complete second order abstract Cauchy problem （（ACP2） for short） in some *** we use these results and those in [1] to discuss the C-（exponential） wellposedness of a kind of （ACP2） with application backgrounds,and develop the results in [2].

关键词： Abstract Cauchy problem C-semigroup C-wellposedness

川东北通南巴复杂构造带气体钻井防漏提速技术

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钻采工艺 2024年第1期47卷 53-59页

作者：杨炳祥何龙罗成波欧彪严焱诚中国石化西南油气分公司产能建设及勘探项目部四川省德阳市618000 中国石化西南油气分公司中国石化西南油气分公司石油工程技术研究院四川省德阳市618000

通南巴构造带受来自米仓山冲断构造带与大巴山弧形冲断构造带的构造叠加作用,断裂和裂缝都较为发育,该区块须家河组以上地层压力低,前期部署的井漏失严重且机械钻速低。文章通过分析应用气体钻井技术的必要性,以井壁稳定、地层可钻性及... 详细信息

通南巴构造带受来自米仓山冲断构造带与大巴山弧形冲断构造带的构造叠加作用,断裂和裂缝都较为发育,该区块须家河组以上地层压力低,前期部署的井漏失严重且机械钻速低。文章通过分析应用气体钻井技术的必要性,以井壁稳定、地层可钻性及井眼净化能力适应性评价为基础,形成了以井身结构优化、注气/泡沫参数和钻具组合及钻进参数优化设计为主体的技术方案,成功应用13井次,不仅避免了上部地层井漏复杂,并且机械钻速平均提升6~9倍以上,为通南巴构造带超万亿方天然气的安全高效开发提供了技术保障。

关键词：通南巴复杂构造带气体钻井防漏提速

A New (t, n) Threshold Signature Scheme Withstanding the Conspiracy Attack

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Wuhan University Journal of Natural Sciences 2005年第1期10卷 107-110页

作者： XIE Qi 1,2, YU Xiu-yuan 3 1.department of mathematics, Zhejiang University, Hangzhou 310027, Zhejiang,china 2.School of Information and Engineering, Hangzhou teachers college, Hangzhou 310012, Zhejiang, china 3.Hangzhou teachers college, Hangzhou 310012, Zhejiang, china Dept. of Math. Zhejiang Univ. Hangzhou 310027 China Sch. of Info. and Eng. Hangzhou Teachers Coll. Hangzhou 310012 China Hangzhou teachers Coll. Hangzhou 310012 China

A ccmspiracy attack is proposed to show that Wang-Li's scheme is instcure,because any t or more group members can impersonate other t member to sign any message withoutholding the responsibility. To avoid the conspiracy attack, this paper prestentsa new (t,n)threshold signature scheme with traceablt signers. A (t. n) threshold signature scheme allows t ormore group members of the group lo generate a signature on behalf of the group, Any less than tmembers cannot generate a valid signature, andany set of the group cannot impersonate another set ofmembers to sign any message without holding the responsibility. In case of disputes., the thresholdsignature can be opened, so that the original signers ean be traced without repealing the secretkeys.

关键词： cryptography threshold signature conspiracy attack identifier tracing