Oligomeric guanidine synthesis assisted by TFA-sensitive arylsulfonylthiourea

Through arylsulfonyl activation of thiourea, efficient synthesis of oligomeric guanidines can be achieved in either solution or solid-phase. Incorporation of TFA-sensitive arylsulfonyl groups, such as Pbf, during the synthesis greatly simplifies deprotection procedures for obtaining the final oligomeric guanidine products.     

一类递归集的Hausdorff维数及Bouligand维数

本文给出递归集的Ｈａｕｓｄｏｒｆｆ维数的下界估计，并由此确定了一类递归集的维数，所获结果包含并推广了Ｂｅｄｆｏｒｄ，Ｄｅｋｋｉｎｇ及文志英、钟红柳等人的有关结果。     

光放大器前置可调光学滤波器

介绍Ｆ－Ｐ干涉滤波器实现中心波长可调的两种机理，给出通过改变腔距来改变中心波工的滤波器的典型结构，并且给出了相应的电压驱动电路，实验表明选择合适的光放大器前置滤波器可以提高系统的灵敏度。     

类锂硅离子软X射线激光研究

在激光等离子体典型参数条件下，利用碰撞－辐模型计算了类锂硅离子５ｆ－３ｄ和４ｆ－３ｄ跃的粒子数反转比率和激光增益系数。讨论了不同热带条件和不同冷却速度下，激光增益系统数的变化。计算结果表明，高功率，短脉冲激光生产的高温等离子体在快速冷却条件下能产生软Ｘ射的线激光增益。     

The Existence of Periodic Orbits for Higher Dimensional Autonomous Systemswith Small Perturbations

ＴｈｅＥｘｉｓｔｅｎｃｅｏｆＰｅｒｉｏｄｉｃＯｒｂｉｔｓｆｏｒＨｉｇｈｅｒＤｉｍｅｎｓｉｏｎａｌＡｕｔｏｎｏｍｏｕｓＳｙｓｔｅｍｓｗｉｔｈＳｍａｌｌＰｅｒｔｕｒｂａｔｉｏｎｓＪｉａｎｇＬｉｑｉｎｇ（蒋里强）；ＺｈｏｕＹｉ（周毅）；ＦａｎＹｅ（范晔）（...     

Interfacial effects on stress distribution in model composites

Raman mechanical spectroscopy was used to examine interfacial effects on the stress distribution in model polydiacetylene fiber/epoxy composites. Epoxy release agents were coated on fiber surfaces to modify the interfacial adhesion properties. The modified fiber surfaces were then characterized by scanning electron microscopy and x-ray photoelectron spectroscopy as well as optical microscopy. No difference in the maximum stress value or stress distribution was observed for the two types of fibers, coated or uncoated, used in composites. This suggests that adhesion properties at the composite interface do not affect tensile stress transfer efficiency nor, therefore, the composite tensile modulus along the fiber axis direction in uniaxial composites. Experimental data were also compared with theoretical calculations assuming perfect bonding between fiber and matrix, and idealized frictional force transfer mechanism at the fiber–matrix interface.     

Integral points of P n −{2n+1 hyperplanes in general position}

Oblatum 4-VI-1990 &; 5-III-1991     

一类几乎最优循环图{C_p(m,m+1,p/a)}

本文比较了循环图类{c_p(n_1,…,n_p)}和{c-p(n_1…,n_p,p/α)}的直径下界。对于p和α满足一定条件的循环图类{c_p(n_1,n_2,p/α)},本文给出了达到或几乎达到此图类直径下界的一类几乎最优循环图{c_p(m,m+1,p/α)}。     

超声波在多糖降解及提取中的应用

本文支综合介绍了超声波在多糖降解和提取中应用的研究进展．着重对超声波在淀粉，壳多糖，细菌多糖的降解和真菌多糖的提取中的应用作了较详细的阐述．     

“J—646”新型光学光敏胶胶合工艺简介

“J—646”光敏胶具有透光率好,收缩率小,粘接强度适中,耐老化,毒性小和成本低廉等特点。本文简要介绍了该胶的胶合工艺。