Alkylation of 2‐pyridinones: Synthesis of novel acyclonucleosides

This paper presents the synthesis of some novel acyclonucleosides containing 2‐pyridinones and 2‐hydroxyethoxymethyl, 2,3‐dihydroxy‐propyl side chain. The tosylate of these nucleosides analogues could be modified to azido derivatives. Also, acyclonucleosides with 1‐ethoxymethyl, 1‐benzyloxymethyl, 1‐methylthiomethy 1 and 2‐hydroxyethyl side chains have been investigated. The O‐alkylated pyridine derivatives were obtained during most reactions.     

Possible modes of internal motions in a 3-electron model system — the2 S e states

A model where three electrons move in the surface of a sphere is used to simulate the² S ^e states of three (valuence) electron atoms with all three electrons at the same shell. A non-co-plane structure and a number of co-plane structures (triangle, straigh rod, and sharp wedge) together with associated modes of motions have been found. It is found that the symmetry has decisive effects on the structure of quantum states. Besides, in the case that the number of the spin-up electrons does not equal to that of the spin-down electrons, the up and down electrons may play different role in constituting the internal motions.     

某些酚类的高温液相色谱行为

建立了高温液相色谱系统,在高温条件下,采用甲醇-水作为流动相,在Polymerx RP-1聚合物(PSDVB)色谱柱上考察了6种酚类样品的色谱行为.实验条件:温度40～160 ℃,流速0.2～5.5 mL/min,流动相中甲醇浓度范围40%～80%.考察了温度、流速和流动相组成对酚类样品的保留、分辨、柱效和系统压力的影响,探讨了酚类样品在聚合物柱上的热力学行为.温度升高2.35℃大约相当于流动相中甲醇浓度增加1%,可以通过改变色谱柱温度调节样品保留和改变选择性.柱温升高,降低了流动相的粘度,允许在高温条件下使用较高的流速实现快速分离.在160℃、V(甲醇):V(水)=40:60,为流动相和3 mL/min流速条件下,可于2.5 min内实现6种酚类的完全分离.     

Nonisothermal Kinetics of Sub‐Solidus Phase Transitions in C10Zn,C16Zn and Their Binary System

Nonisothermal kinetics of the solid‐solid phase transition in (n‐C₁₀H₂₁NH₃)₂ZnCl₄(C₁₀Zn), (n‐C₁₆H₃₃NH₃)₂ZnCl₄(C₁₆Zn) and their binary system were determined by Kissinger and Ozawa methods from DSC measurements. The activation energy E_a of the binary system shows a waving dependence on W_C10Zn%, which is caused by not only an intermediate (C₁₀H₂₁NH₃)(n‐C₁₆H₃₃NH₃)ZnCl₄ but also three solid solution ranges (α, β, γ) in the phase diagram of C₁₀Zn‐C₁₆Zn. The variations of the layer d‐spacing are also convenient for the above result.     

封闭压力酸溶-ICP-MS法分析地质样品中47个元素的评价

对封闭压力酸溶－ICP－MS法同时测定地质样品中47个元素的效果和适用范围进行了实测评价。并对溶样条件进行了优化。实验结果表明，HF－HNO3高温高压酸溶是一种有效的样品分解方法，在所测定的47个元素中，大部分元素如Li,Be,Ti,V,Mn,Co,Ni,Cu,Zn,As,Zr,Nb,Mo,Cd,In,Sn,Sb,Hf,Ta,W,Tl,Pb,Bi等在大多数标样中在三种取样量下都可以得到满意的回收率。而Sc,Cr,Ga,Y,REE,Rb,Cs,Sr,Ba,Th,U等元素在大部分样品中则随取样量减少，回收率上升，在一些样品中，当取样量降至25mg时，可以获得满意的回收率。用王水代替HNO3复溶残渣，利用氯离子的络合作用促进复溶，使许多元素的回收率有了明显的提高。     

Chemical Constituents of Ailanthus triphysa

Two new compounds,8(14),15-isopimaradiene-2α，３α，19-triol(1),and 6α，７β－dihydroxy-17(20)-cis-5α－pregna-16-one(2),together with four known copounds,a oxygenated rare phyllocladane,phyllocladan-16α，19-diol(3),kaempferol-3-0-β－Ｄ-galactopyranosied,kaempferol-3-0-α－Ｌ－rhamnopyranoside and scopoletin, were isolated from the leaves of Ailanthus tripysa.Structures of 1-3 were elucidated on the basis of spectroscopic data as compared with related compounds.     

一种非晶硅膜改性弹性玻璃毛细管交联中等极性固定相色谱柱的制备

研究了非晶硅膜改性的弹性玻璃毛细管交联ＯＶ－１７０１中等极性固定相色谱柱。在适当温度下，采用过氧化二异丙苯（ＤＣＵＰ）游离基引发交联ＯＶ－１７０１固定液，成功地制备了交联ＯＶ－１７０１柱，该柱具有柱效高、惰性好、耐溶剂、抗腐蚀和耐高温等性能，是一种新型高性能的中等极性交联柱。     

Synthesis,Reactivity, and Structural Characterization of Dioxovanadium(V) Complexes with Tridentate Schiff Base Ligand: Vanadium Complexes in Supramolecular Networks

The synthesis, characterization and crystal structure analysis of the ammonium salt of the dioxovanadium(V) complex NH₄[VO₂(salhyph)] with the tridentate Schiff base ligand derived from salicylaldehyde and benzoic acid hydrazide (H₂salhyph) is reported. NH₄[VO₂(salhyph)] crystallizes in the monoclinic space group Pn with a = 708.8(2), b = 1444.3(3), c = 717.1(2) pm and β = 101.09(2)°. The vanadium atom of the dioxovanadium(V) moiety has a distorted square‐pyramidal coordination geometry. Extensive hydrogen bonding is observed between the ammonium cation and the oxygen atoms coordinated to the vanadium atom yielding to a two‐dimensional network, where the complex anions are arranged in a bilayer. Additional crystal packing within the bilayer appears to be controlled mostly by π stacking between the aromatic rings of the ligand. The reactions of NH₄[VO₂(salhyph)] with several proton acidic compounds including water, methanol, and proton acids lead to neutral monooxovanadium(V) and dioxovanadium(V) complexes ([VO₂(Hsalhyph)], [V₂O₃(salhyph)₂] and [VO(OMe)(salhyph)(HOMe)]).     

脉冲色谱法测定金属铬中的氢

本文采用脉冲色谱法温室金属铬合中的氢含量，用正交试验法选择了最佳分析条件（含加热时间，加热初级电流，试样重量，浴料及浴比），建立了锡浴法测定铬中氢的方法，方法精度为５．５％。     

羰基铁-硫醇(酚)-三乙胺体系的研究——某些δ,π-μ-烯基铁硫配合物的合成及结构

本文利用由Fe_3(CO)_(12)、硫醇(或硫酚)、三乙胺所形成的活性中间物Et_3NH[(μ-CO)(μ-RS)Fe_2(CO)_6]与β-溴代苯乙烯或β-氯代乙烯基酮反应,合成了3个通式为(μ-RS)(μ-PhCH=CH)Fe_2(CO)_6(R=Et,t-Eu,Ph)和6个通式为(μ-RS)(μ-ZCOCH=CH)Fe_2(CO)_6(R=Et,t-Bu;z=Me,Ph,p-MeC_6H_4)σ,π-μ-烯基铁硫配合物.