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101.
The compatibility of cycloaliphatic and aromatic multifunctional epoxides with several epoxide resins allows the development of a wide range of cationic radiation‐curable formulations. The influence of different “epoxide resin‐monomer” systems UV‐cured in the presence of suitable cationic photoinitiators on the resulting physicochemical film properties was studied, and the results are stated. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
102.
有限群G的子群H称为G的BNA子群,若对任意的x∈G有H^(x)=H或x∈.若有限群G的所有素数阶和4阶循环子群都是G的BNA子群,则称G为CBNA群.本文主要刻画CBNA群的结构,并且给出所有真子群都是CBNA群的完全分类.  相似文献   
103.
In this article, we classify connected commutative (locally) Nash groups, which is a continuation of our previous work on the classification of abelian Nash manifolds. Our results generalize the classification of the one-dimensional case by Madden-Stanton and the two-dimensional case by Baro-Vicente-Otero. Moreover, we determine the affineness and toroidal affineness of a connected commutative Nash group.  相似文献   
104.
In this paper, the author computes canonical connections and KobayashiNomizu connections and their curvature on three-dimensional Lorentzian Lie groups with some product structure. He defines algebraic Ricci solitons associated to canonical connections and Kobayashi-Nomizu connections. He classifies algebraic Ricci solitons associated to canonical connections and Kobayashi-Nomizu connections on three-dimensional Lorentzian Lie groups with some product structure.  相似文献   
105.
We construct left invariant special Kähler structures on the cotangent bundle of a flat pseudo-Riemannian Lie group. We introduce the twisted cartesian product of two special Kähler Lie algebras according to two linear representations by infinitesimal Kähler transformations. We also exhibit a double extension process of a special Kähler Lie algebra which allows us to get all simply connected special Kähler Lie groups with bi-invariant symplectic connections. All Lie groups constructed by performing this double extension process can be identified with a subgroup of symplectic (or Kähler) affine transformations of its Lie algebra containing a nontrivial 1-parameter subgroup formed by central translations. We show a characterization of left invariant flat special Kähler structures using étale Kähler affine representations, exhibit some immediate consequences of the constructions mentioned above, and give several non-trivial examples.  相似文献   
106.
程帆  邓斌超  尹贻林 《运筹与管理》2022,31(10):227-234
协调政府与社会资本合作的利益分歧,进而实现个体理性向集体理性的趋同,这是纾解PPP项目合作困境的切入点之一。基于合作博弈理论,本文构建PPP项目非完全利益群体的合作形成机制,分析政府与社会资本间“合作共赢”的必要因素。研究表明,由政府与社会资本组成的PPP项目非完全利益群体,可在“理性-效用转移-有效协商”机制的协同作用下主动采取最优合作策略。其中,理性机制验证了政府与社会资本达成合作意向的前提,效用转移机制可实现二者之间的风险-收益对等,有效协商机制将达成政府与社会资本合作的帕累托均衡。  相似文献   
107.
LetX be a smooth projective variety over an algebraically closed fieldk. We repeat Bloch's construction of aG m -biextension (torseur)E over CH hom p (X)×CH hom q (X) forp+q=dim(X)+1. First we show that in characteristic zeroE comes via pullback from the Poincaré biextension over the corresponding product of intermediate Jacobians which has been conjectured by Bloch and Murre. Then the relations betweenE and various equivalence relations for algebraic cycles are studied. In particular we reprove Murre's theorem stating that Griffiths' conjecture holds for codimension 2 cycles, i.e. every 2-codimensional cycle which is algebraically and incidence equivalent to zero has torsion Abel-Jacobi invariant.  相似文献   
108.
Amino-functionalized latex particles were obtained batchwise by emulsion copolymerization of styrene and vinylbenzylamine hydrochloride (VBAH) in the presence of 2-2-Azobis(2-amidinopropane) HCl (V50). Size monodispersity of the particles was improved by using divinylbenzene (DVB) as a third monomer at a 2% molar ratio. Surface amino group titration was performed spectrometrically with N-succinimidyl 3-(2 pyridyldithio)propionate (SPDP). The yields of functional monomer incorporation were up to 85%.  相似文献   
109.
The maximum number of non-vanishing and independent second order photoelastic coefficients required by the seven pentagonal and the two icosahedral point groups 5(C5), (S10), (C5h ), m2(D5h ), 52(D5), 5m(C5v ), 2m(D5d ); 235(I), 2/m (I h )—that describe the quasicrystals symmetry groups in two and three dimensions—is obtained. The schemes of non-vanishing and independent coefficients have been calculated and listed. Finally the results of this group-theoretical study are briefly discussed.  相似文献   
110.
An example of a geodesic in with conjugate points is given, thus providing an affirmative answer to a question of V.I. Arnold.

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