HYDROGEN BONDING IN THE CRYSTAL OF 1,1′-((1E,1′E)-(PYRIDINE-3,4-DIYLBIS (AZANYLYLIDENE))BIS(METHANYLYLIDENE))- BIS(NAPHTHALEN-2-OL) ACETONITRILE SOLVATE: COMBINED EXPERIMENTAL AND THEORETICAL STUDY

Journal of Structural Chemistry - The title compound, 1,1′-((1E,1′E)-(pyridine-3,4-diylbis(azanylylidene))bis(methanylylidene))bis (naphthalen-2-ol) (1), was synthesized and...     

Isosteviol acylphosphonates

A reaction of ent-16-oxobeyeran-19-oic acid (isosteviol) with an excess of PCl3 gives the corresponding acid chloride as a sole product. The latter reacts with trialkyl phosphites and dialkyl trimethylsilyl phosphites to yield acylphosphonates inert to nucleophilic reagents.     

The Asymptotic Distributions of Sums of Records

LetX ₁,X ₂... be a sequence of i.i.d. random variables and let be the associated (upper) record sequence. Resnick (1973) identified the class of all possible limit distributions for . Here we focus on sums of records, . We describe three cases in which T _n can be normalized to have a non-trivial limiting distribution. The problem of identifying all possible limit laws for normalized sums of records remains open.     

用强阴离子交换毛细管电色谱分离阴离子化合物

对阴离子性化合物在强阴离子交换毛细管电色谱中的保留行为进行了研究。发现样品中固定相上的吸附使样品的保留因子k^*变小,柱小的分离能力减小;而电压的增大,使酸性样品的k^*也增大,并且电压的改变也能改变分离的选择性;样品保留因子的对数值随着缓冲液离子强度的对数值的增大而线性减小;样品也强阴子交换毛细管电谱和毛细管区带电泳中有不同的保留行为。     

稀土(镧、镨、钕)氯化物与苯并咪唑配合物的光谱特性

用傅里叶变换红外光谱、喇曼光谱、紫外光谱、荧光光谱和X粉晶衍射等多种光谱手段对氯化稀土(La、Pr、Nd)与苯并咪唑(Bim)配合物进行了分析,对配合物的光谱特性和结构进行了讨论和表征.