MULTIPLICATION OF WEAK FUNCTIONS

This paper is a contionuation of [1] and is concerned with multiplication of weak functions. Here the weak functions are treated as generalized expansions in Hermite functions in [2].     

醋酸烯丙酯选择性地合成烯丙基硒醚

醋酸烯丙酯被Pd(PPh3)4-SmI2还原，并发生中间体π-烯丙基钯络合物的极性 反转，而后与芳基硒溴化物作用，生成烯丙基硒醚．     

含氧、氮配位的杂单环有机锡配合物的合成

通过二苄(二苯)基二氯化锡分别与芳醛缩(异)烟酰肼的钠盐反应,合成了8种新的有机锡(Ⅳ)配合物,其结构经1H NMR,IR和元素分析表征.配合物可能是含氧、氮配位的杂单环五配位结构.     

3-(四氯化锡)-丙酸甲酯阴离子的合成及晶体结构

在用酯基锡MeO2CCH2CH2SnCl3合成配合物MeO2CCH2CH2SnCl3·(2-OHC6H4CH=NC6H5)时,其配合物的甲苯溶液放置培养单晶时(放置十天以上)会发生分解生成配合物MeO2CCH2CH2SnCl4—·H+。研究了标题化合物的合成反应,用元素分析、IR、NMR对配合物进行了表征,并测定了晶体结构。为正交晶系,空间群为P2cn, a=7.852(2), b=12.236(1), c=16.952(4) ? V=1628.7?, Z=4, Dc=1.79g/cm3, F(000)= 860,m=22.2cm—1(Mo),R=0.0449, Rw=0.0382。标题化合物的空间构型为畸变的八面体构型,中心锡原子的配位数为6。     

有界平均振幅空间上的乘法算子

有界平均振幅空间的研究在算子理论及全纯空间的研究中具有重要的作用.主要研究了有界平均振幅空间上乘法算子的性质,并且得到了托普里兹算子有界性及紧性的条件.     

Ni(II), Co(II), and Cu(II) complexes incorporating 2-pyrazinecarboxylic acid：Synthesis,characterization, electrochemical evaluation,and catalytic activity for the synthesis of 2H-indazolo[2,1-b]phthalazine-triones

Three complexes containing 2-pyrazinecarboxylate (pzca–), including [Ni(pzca)2(H2O)2], [Co(pzca)2(H2O)2], and [Cu(pzca)2(H2O)2], have been synthesized and characterized using physico-chemical and spectroscopic methods. Furthermore, the structure of each complex was determined by single-crystal X-ray diffraction. All three complexes have an octahedral geometry, where the metal ion chelated by two carboxylate oxygens, two nitrogen atoms belonging to pyrazinic acid molecules, and two oxygen atoms of two water molecules. The catalytic activities of these complex-es were also investigated in the green synthesis of 2H-indazolo[2,1-b]phthalazine-triones by the reaction of hydrazine hydrate with an arylaldehyde, phthalic anhydride, and dimedone in acetic acid.     

茂金属化合物/Zn/BDGE/MAO催化体系合成aPS-b-P(S-co-E)-b-PE嵌段共聚物的研究

采用单茂钛化合物CpTiCl3,有机环氧化合物1,4-丁二醇二缩水甘油基醚(BDGE),金属锌(Zn)及甲基铝氧烷(MAO)为催化体系,通过自由基聚合和配位聚合机理合成无规聚苯乙烯-b-聚(苯乙烯-co-乙烯)-b-聚乙烯(aPS-b-P(S-co-E)-b-PE).探讨了温度、时间、乙烯压力及Al/Ti摩尔比对共聚合的影响.所得嵌段共聚物采用DSC,WAXD,GPC和13C-NMR等手段进行了表征.结果表明该共聚物是苯乙烯/乙烯嵌段共聚物,聚苯乙烯链段是无规的,聚乙烯链段具有结晶性.     

A simple characterization of weighted Sobolev spaces with bounded multiplication operator

In this paper we give a simple characterization of weighted Sobolev spaces (with piecewise monotone weights) such that the multiplication operator is bounded: it is bounded if and only if the support of μ₀ is large enough. We also prove some basic properties of the appropriate weighted Sobolev spaces. To have bounded multiplication operator has important consequences in Approximation Theory: it implies the uniform bound of the zeros of the corresponding Sobolev orthogonal polynomials, and this fact allows to obtain the asymptotic behavior of Sobolev orthogonal polynomials.     

Identification de la relation de dispersion dans les barresIdentification of the dispersion relation in rods

Dispersion and attenuation of longitudinal waves in elastic or weakly viscoelastic rods are measured by analysing the resonant frequencies present in the strain spectrum due to an unknown loading. The method takes the finite measuring time of the test into account. It is applied to an aluminium bar, in which the dispersion relation is identified very accurately at frequencies up to 60 kHz. To cite this article: R. Othman et al., C. R. Mecanique 330 (2002) 849–855.     

Multiplication operators in Köthe-Bochner spaces

Let X be a Banach space and E an order continuous Banach function space over a finite measure μ. We prove that an operator T in the Köthe-Bochner space E(X) is a multiplication operator (by a function in L^∞(μ)) if and only if the equality T(g〈f,x^∗〉x)=g〈T(f),x^∗〉x holds for every g∈L^∞(μ), f∈E(X), x∈X and x^∗∈X^∗.