1Π态双原子分子中关于(A)量子干涉的微分干涉角

Sha等在静态池实验中观察到了转动能量转移中的碰撞量子干涉,并且计算了决定跃迁散射截面的积分干涉角(J.Chem.Phys.,1995,102:2772).由于积分干涉角是微分干涉角的平均效应,为了得到更精确的信息,进行了分子束实验.作者文运用含时微扰的一级波恩近似理论,提出了衡量干涉程度的1П态双原子分子中关于Λ量子干涉的微分干涉角.利用各向异性相互作用势计算了其干涉角.得到分子束实验中微分干涉角随实验参数,包括实验温度、碰撞伴、作用距离和转动量子数变化的关系.并且讨论了影响干涉角的各种参数.此理论模型对理解和进行分子束实验是非常重要的.     

1~Π态双原子分子中关于Λ量子干涉的微分干涉角(英文)

Sha等在静态池实验中观察到了转动能量转移中的碰撞量子干涉,并且计算了决定跃迁散射截面的积分干涉角(J.Chem.Phys.,1995,102:2772).由于积分干涉角是微分干涉角的平均效应,为了得到更精确的信息,进行了分子束实验.作者文运用含时微扰的一级波恩近似理论,提出了衡量干涉程度的1П态双原子分子中关于Λ量子干涉的微分干涉角.利用各向异性相互作用势计算了其干涉角.得到分子束实验中微分干涉角随实验参数,包括实验温度、碰撞伴、作用距离和转动量子数变化的关系.并且讨论了影响干涉角的各种参数.此理论模型对理解和进行分子束实验是非常重要的.     

1Π态双原子分子中关于量子干涉的微分干涉角

Sha等在静态池实验中观察到了转动能量转移中的碰撞量子干涉,并且计算了决定跃迁散射截面的积分干涉角(J.Chem.Phys.,1995,1022772).由于积分干涉角是微分干涉角的平均效应,为了得到更精确的信息,进行了分子束实验.作者文运用含时微扰的一级波恩近似理论,提出了衡量干涉程度的1П态双原子分子中关于Λ量子干涉的微分干涉角.利用各向异性相互作用势计算了其干涉角.得到分子束实验中微分干涉角随实验参数,包括实验温度、碰撞伴、作用距离和转动量子数变化的关系.并且讨论了影响干涉角的各种参数.此理论模型对理解和进行分子束实验是非常重要的.     

^1Π态双原子分子中关于∧量子干涉的微分干涉角

Sha等在静态池实验中观察到了转动能量转移中的碰撞量子干涉,并且计算了决定跃迁散射截面的积分干涉角（J.Chem.Phys.,1995,102：2772）.由于积分干涉角是微分干涉角的平均效应,为了得到更精确的信息,进行了分子束实验.作者文运用含时微扰的一级波恩近似理论,提出了衡量干涉程度的^1П态双原子分子中关于Λ量子干涉的微分干涉角.利用各向异性相互作用势计算了其干涉角.得到分子束实验中微分干涉角随实验参数,包括实验温度、碰撞伴、作用距离和转动量子数变化的关系.并且讨论了影响干涉角的各种参数.此理论模型对理解和进行分子束实验是非常重要的.     

真空紫外光激发下铕掺杂的硼酸盐发光特性与结构的关系

为了改进现有或开发新的PDP用荧光材料,必须考虑荧光材料的发光性质,如吸收峰位置、能量由基质到发光中心的传递效率、色纯度、发光强度等,而这些性质与荧光材料的结构有着紧密的联系.在研究了多种三价铕掺杂的硼酸盐荧光材料的基础上,比较了它们在真空紫外光激发下的吸收特性,定性讨论了能量从基质到发光中心的传递效率,分析了影响红色荧光材料色纯度的有关性质.     

转动传能中的量子干涉: 干涉角和相对速度的关系

考虑一级含时波恩近似和长程相互作用势, Sun提出了转动传能中的量子干涉模型.在静态池中CO A1Π～ e 3Σ-和He碰撞的实验已经成功模拟.为了从实验中直接获得碰撞速度和干涉角的关系, Sha提出了利用分子束和离子速度成像技术的实验.作为理论研究干涉角和碰撞速度的关系,计算了不同速度下的干涉角,同时获得了变化的趋势.对在分子束条件下(通过控制碰撞速度来控制干涉角)实验具有指导意义.     

基质辅助激光解吸电离飞行时间质谱对环状芳香多硫寡聚物的研究

采用基质辅助激光解吸电离飞行时间质谱(MALDI TOF-MS)对环状芳香硫醚的寡聚产物进行了测定和分析,首次确定了这类采用其它传统方法难以分析的难溶多硫环状芳香硫醚寡聚物的结构;研究了芳香烃部分随聚合度不同的分布规律和芳香烃部分相同的条件下S原子数目不同而引起的组分变化的规律;讨论了4种基质的辅助解吸电离效果和离子化试剂对测定结果的影响,探索出测定这类寡聚物的最佳条件.     

稀土配合物杂化发光材料的组装及光物理性质研究进展

稀土配合物兼具无机物稳定性好以及有机物荧光量子效率高的优点,而且具有可设计性,制备简便,容易修饰,荧光性质优异（发射谱带窄、色纯度高、荧光寿命长、量子产率高以及发射光谱范围覆盖可见和近红外光区等）．但配合物的光、热、化学稳定性和机械加工性能相对较差,因而限制了其在很多领域中的实际应用．近年来的研究表明,将稀土配合物引入到各种基质材料中可以改善其稳定性及机械加工性能,并对其光物理性质产生调制作用．根据基质材料的不同,杂化材料可分为无机基质、无机／有机复合基质及有机基质杂化材料．本文综述了这些不同基质稀土配合物杂化发光材料的研究进展,探讨了主客体间相互作用对杂化材料光物理性质及稳定性的影响,为实现稀土配合物杂化发光材料在光学器件领域（LED照明、光纤维、光学放大器及激光等）及生命分析领域的应用提供了重要的理论依据．     

镧系元素螯合物热致变色作用的研究(Ⅱ) 镧、钕、钆二甲酚橙螯合物水溶液的热致变色作用及机理

用分光光度法研究了镧系离子La(Ⅲ)、Nd(Ⅲ)和Gd(Ⅲ)的二甲酚橙(XO)螯合物水溶液的可逆热致变色规律。测定了螯合物的组成及条件稳定常数。探讨了体系酸度、离子强度及配体浓度对热致变色作用的影响。初步研究表明,Ln(Ⅲ)-XO螯合物水溶液中存在两种不同颜色的螯合物质子离解平衡:体系呈现的热致变色作用是平衡常数随温度而变化所致。     

汽车用聚氨酯减振材料的结构与性能

利用扫描电镜(SEM)对减振材料的微孔结构进行了表征;用万能材料试验机(UMTM)、动态热机械分析仪(DMA)、旋转流变仪表征了减振材料在不同条件下的力学及减振性能.研究发现:不同聚氨酯减振材料进入非线性形变区域的压缩形变大小与微孔的面积占有率相关.我们认为聚氨酯泡沫减振材料在小压缩应变下应力的缓慢增加主要是由微孔的变形引起的,随着压缩应变进一步增加,微孔的变形接近极限,此时应力的快速增加主要由聚氨酯本体的力学性能决定.聚氨酯减振材料的损耗能随着压缩应变的增加而增加,减振性能好的材料具有较大的损耗能.聚氨酯减振材料的损耗角随着压缩频率的增加而略有增加,其影响减振材料在不同使用频率下的减振和产热性能.聚氨酯减振材料的损耗角随着温度的变化而发生变化,耐寒性和耐热性好的材料,损耗角随温度平缓变化的温度范围更宽.当减振材料受到一定的负载后,材料的损耗角降低.     

α-Amino acid derived enaminones and their application in the synthesis of N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates and other heterocycles

A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.     

Specific intramolecular aromatic CH insertion of diazosulfonamides

The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp³)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp²)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp²)?H and aliphatic 1,5- and 1,6-C(sp³)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp³)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp²)?H insertion.     

N-Heterocyclic carbene-palladacyclic complexes: synthesis,characterization and their applications in the C-N coupling and α-arylation of ketones using aryl chlorides

N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).     

Iodine-mediated oxidative Pictet-Spengler reaction using terminal alkyne as the 2-oxoaldehyde surrogate for the synthesis of 1-aroyl-β-carbolines and fused-nitrogen heterocycles

An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y₁ and Y₂. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.     

Facile synthesis of bicyclic 1-arylpyrazol-5-ones

In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.     

Synthesis of pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles by Curtius reaction in Morita-Baylis-Hillman derivatives

Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described.     

正丁胺对激光染料荧光谱影响的研究

用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在.     

Cu0-catalysed 1,3-dipolar cycloadditions of α-amino acid derived N,N-cyclic azomethine imines to ynones

A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu⁰ as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than Cu^I in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT).     

Synthesis and antioxidative/anti-inflammatory activity of novel fullerene–polyamine conjugates

(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C₆₀, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine.