对甲苯磺酸催化合成乙酸正丁酯

用对甲苯磺酸作冰乙酸和正丁醇的酯化催化剂，成功地合成了乙酸正丁酯，考察了影响反应的因素，探讨并找到了较好的反应条件：乙酸l00mmol，n(冰乙酸)：n(正丁醇)：n(催化剂)=1：3：0．006，反应时间1．5h，不另加带水剂，产率达99．14％。     

α－烯丙基甘油醚的合成新方法

在路易斯酸催化下，烯丙醇和环氧氯丙烷经加成、环化和水解后得到标题化合物，该法比文献报道的甘油－氯丙烯法产率提高约１０％。     

Weak Factorization Systems and Topological Functors

Weak factorization systems, important in homotopy theory, are related to injective objects in comma-categories. Our main result is that full functors and topological functors form a weak factorization system in the category of small categories, and that this is not cofibrantly generated. We also present a weak factorization system on the category of posets which is not cofibrantly generated. No such weak factorization systems were known until recently. This answers an open problem posed by M. Hovey.     

A Mössbauer study of spin-pinning in the oxide surface layer on fine iron particles

Fine α-Fe particles coated with an oxide surface layer were prepared by the evaporation technique. The spin pinning in the oxide surface layer were studied by means of the Mössbauer effect in an applied field of 6T during a thermal-cycle process. The anisotropy energy on the surface was estimated.     

极贫金属星CS22892-052重元素丰度的研究

根据太阳系的重核素丰度分布 ,提出了一种利用 3种中子俘获过程的典型代表元素的丰度观测值计算贫金属星重核素丰度的方法 ,并计算了极贫金属星CS2 2 892 0 5 2的重元素丰度分布     

Top介子在高能正负电子对撞机上的产生

在顶色辅助的人工色(TC2)模型框架下,研究了中性top介子和顶夸克的联合产生过程e+e–→ttπ0t.结果显示此过程的产生截面比标准模型和最小超对称标准模型中e+e–→ttH过程的产生截面都要大.在TC2模型合理的参数空间内,其产生截面可达20fb.通过此过程可在将来的对撞机上探测中性top介子.     

Vibratilicin: a Novel Compound from the Basidiomycete Cortinarius vibratilis

A novel N‐containing compound, vibratilicin (=3‐[3‐(dimethylamino)‐4‐(hydroxyamino)‐4‐oxobutoxy]‐2‐(palmitoyloxy)propyl (9E,12E)‐octadeca‐9,12‐dienoate; 1 ), was isolated from the fruiting bodies of the basidiomycete Cortinarius vibratilis Fr. Compound 1 is a representative of the rare natural products containing hydroxamic acid moieties, and can be viewed as a derivative of neoengleromycin ( 2 ). Also isolated from the same fungus were five known compounds: ergosta‐5,7,22‐trien‐3β‐ol, 5α,8α‐epidioxyergosta‐6,22‐dien‐3β‐ol, p‐anisic acid, N‐(2‐hydroxyhexadecanoyl)‐4‐sphingenine, and (4E,8E)‐2‐N‐(2′‐hydroxypalmitoyl)‐1‐O‐(β‐D ‐glucopyranosyl)‐9‐methyl‐4,8‐sphingadienine. Their structures were determined mainly spectroscopically, including 2D‐NMR techniques (HMBC, HMQC, ¹H,¹H‐COSY).     

Bager第二图的改进

１９７３年绘制的Ｂａｇｅｒ第二图，包含了８３个关于三角形角变元的规范对称函数的不等式。通过细致的分析，本文证明了其中１５个三角不等式可被１１个更强的不等式所取代，从而改进了Ｂａｇｅｒ第一图．     

一个分析不等式的反向

本文建立了作者在１９９０年证明的一个分析不等式的反向形式；作为其直接推论，我们得到了Ｊａｎｏｕｓ－Ｋｌａｍｋｉｎ猜想（１９９２年）等一系列有意义的结果。     

汉语句法的分段循环分析策略

定义了汉语的分段语法，并根据自然语言的分段循环结构，提出了汉语的分段循环分析策略．它的基本思想是确定语言的一组基本范畴，其相应的句法规则段及其之间的优先关系，对于每一个句法规则段，分别依次采用改进的Ｋｉｌｂｕｒｙ算法、它的优点在于分析过程中的项目集比较小，而且避免了无用分析树的产生，从而大大提高了分析效率．