La-Sr-Ni-O系复合氧化物的合成及La_(2-x)Sr_xNiO_4体系催化性能研究

用硝酸盐分解法(N-法)和柠檬酸络合法(L-法)合成了La-Sr-Ni-O系复合氧化物.用XRD技术考察了样品组成、制备条件及灼烧气氛等对产物结构的影响.结果表明:按La_(1-x)Sr_xNiO_3计量比,用N-法合成只能形成四方体心K_2NiF_4结构的A_2BO_4型复合氧化物.而采用L-法,通过改变条件,在0.0≤x≤0.2范围内可形成菱形晶系钙钛矿结构的复合氧化物.另外,用L-法合成La_(2-x)Sr_xNiO_4系列样时发现,制备条件及灼烧温度、气氛对样品结晶态存在较大的影响,高温、空气氛下可形成高结晶态的K_2NiF_4结构复合氧化物.La_(2-x)Sr_xNiO_4体系CO催化氧化活性研究表明,随x(Sr~(2+)取代量)增加,CO的转化率增加.     

catena‐Poly[[[bis(μ‐4,5‐dihydrothiazole‐2‐thiolato)‐tetrahedro‐tetracopper(I)]‐di‐μ‐4,5‐dihydrothiazole‐2‐thiolato] dihydrate]

The title compound, {[Cu₄(C₃H₄NS₂)₄]·2H₂O}_n, was produced by diffusing a solution of 2‐mercapto­thia­zoline in tetra­hydro­furan into a solution of CuCl in CH₃CN at room temperature. The structure is characterized by self‐assembled one‐dimensional chains that are condensed from butterfly‐like [Cu(C₃H₄NS₂)]₄ tetrameric units via double S‐bridging at opposite ends. The Cu—Cu distances within the Cu₄ butterfly cluster are in the range 2.7103 (10)–2.9764 (10) Å, while the shortest Cu?Cu intercluster distance is 3.468 (1) Å, much longer than the sum of the van der Waals radii.     

平均迭代压缩映射存在不动点的充要条件

本文剖析文［１］的定义，举出反例说明文［１］结论不成立，并给出平均迭代压缩映射存在不动点的两个充要条件。     

Based algebras and standard bases for quasi-hereditary algebras

Quasi-hereditary algebras can be viewed as a Lie theory approach to the theory of finite dimensional algebras. Motivated by the existence of certain nice bases for representations of semisimple Lie algebras and algebraic groups, we will construct in this paper nice bases for (split) quasi-hereditary algebras and characterize them using these bases. We first introduce the notion of a standardly based algebra, which is a generalized version of a cellular algebra introduced by Graham and Lehrer, and discuss their representation theory. The main result is that an algebra over a commutative local noetherian ring with finite rank is split quasi-hereditary if and only if it is standardly full-based. As an application, we will give an elementary proof of the fact that split symmetric algebras are not quasi-hereditary unless they are semisimple. Finally, some relations between standardly based algebras and cellular algebras are also discussed.     

用硫化助熔剂法合成红外上转换材料的研究

本文采用一种优化的硫化助熔剂方法合成了红外上转换材料,这种材料能够在室温下将红外光转换成可见光。这种新工艺在反应效率、生产成本、环境保护、工艺难度等方面均优于传统的热熔工艺。文章给出了红外上转换材料的激励光谱和发射光谱。     

Determination of Herbicide Residues in Garlic by GC–MS

A rapid multi-residue method has been developed for the determination of 16 herbicides in garlic. The analytical procedure is based on prior microwave heating prevention of the generation of sulfur-containing compounds. The garlic samples which had been pretreated were extracted with acetonitrile and cleaned up by solid-phase extraction. The herbicide residues were detected by gas chromatography–mass spectrometry with selected ion monitoring. The recoveries of 16 herbicides ranged from 69.0 to 105.4% with the relative standard deviations (RSD) below 10.1%. The limit of quantification (LOQ) ranged from 0.003 to 0.015 mg kg^?1.     

EXISTENCE OF OPTIMAL STRONG PARTIALLY BALANCED DESIGNS

A strong partially balanced design SPBD（v, b, k; λ,0） whose b is the maximum number of blocks in all SPBD（v, b, k; λ, 0）, as an optimal strong partially balanced design, briefly OSPBD（v, k, λ） is studied. In investigation of authentication codes it has been found that the strong partially balanced design can be used to construct authentication codes. This note investigates the existence of optimal strong partially balanced design OSPBD（v, k, 1） for k = 3 and 4, and shows that there exists an OSPBD（v, k, 1） for any v ≥ k.     

Spectral distributions of harmonic generation from electron oscillation driven by intense femtosecond laser pulses

The characteristics of harmonic radiation due to electron oscillation driven by an intense femtosecond laser pulse are analyzed considering a single electron model. An interesting modulated structure of the spectrum is observed and analyzed for different polarization. Higher order harmonic radiations are possible for a sufficiently intense driving laser pulse. We have shown that for a realistic pulsed photon beam, the spectrum of the radiation is red shifted as well as broadened because of changes in the longitudinal velocity of the electrons during the laser pulse. These effects are more pronounced at higher laser intensities giving rise to higher order harmonics that eventually leads to a continuous spectrum. Numerical simulations have further shown that by increasing the laser pulse width broadening of the high harmonic radiations can be limited.     

稀释磁性半导体Sn1-xMnxO2的室温铁磁性

采用固相反应法，制备了不同成分的稀释磁性半导体Sn_1-xMn_xO ₂(x=002，004，006)．利用x射线衍射和傅里叶变换红外光谱法证明 了锰均匀地掺杂到二氧化锡中．在室温下研究了掺锰二氧化锡基稀释半导体的磁性，发现它具有明显的铁磁性 ，同时对磁性的强弱与锰的含量和烧结温度的关系作了研究． 关键词： 稀释磁性半导体 掺杂 烧结 铁磁性 1-xMn_x O₂')" href="#">Sn_1-xMn_x O₂