CS码应用于电报通信网时的系统设计

本文叙述了保密和纠错编码在电报通信系统设计中的应用,介绍了系统的性能以及在公众电报网中的通信方式.     

Inhibition of aldose reductase by dihydroflavonols inEngelhardtia chrysolepis and effects on other enzymes

Astilbin and neoastilbin, dihydroflavonol rhamnosides fromEngelhardtia chrysolepis, showed potent inhibition of lens aldose reductase. Kinetic analysis showed astilbin exhibited uncompetitive inhibition against bothdl-glyceraldehyde and NADPH. These taxifolin glycosides were selective inhibitors of aldose reductase with no inhibition of NADH oxidase.     

有限单元法计算n室薄壁断面可畸变直箱结构的自振频率

本文以箱形断面的薄壁杆杆段为单元,建立了直杆单元的刚度矩阵和单元质量矩阵,对两个例子进行了数字计算,同时也建立了能量法求固有频率的算式,检验了有限元法的结果。此外还演引了固有振动的微分方程组并求得解,解析法的结果也验证了有限元法的计算公式。     

中整环的构造

若结合环R对其任一真理想I,R/I恒为整环,则称R为中整环,本文给出了一些中整环的构造定理,从而基本上解决并推广了文〔1〕中提出的中整环结构问题。     

Dissolution and diffusion of TiO2 in the CaO-Al2O3-SiO2 slag

The dissolution of TiO2 in the CaO-Al2O3-SiO2 slag under static conditions was studied in the temperature range from 1643 K to 1703 K. After TiO2 dissolved, the microstructure of the interface between TiO2 and the slag was observed by scanning electron microscopy, and the concentration profiles of Ti4＋and other ions across the TiO2/slag interfaces were analyzed by energy-dispersive X-ray spectroscopy. On the basis of these results, the dissolution behavior of TiO2 was evaluated, and the diffusivity of Ti4＋in the bulk slag was estimated. Ac-cording to the Stokes-Einstein relation, the viscosity calculated by a previously reported model gave a diffusivity of Ti4＋ions greater than that estimated by the concentration profiles of Ti4＋ions. The mechanism of TiO2 dissolution in the CaO-Al2O3-SiO2 slag is discussed in de-tail.     

Dripping and evolution behavior of primary slag bearing TiO<Subscript>2</Subscript> through the coke packed bed in a blast-furnace hearth

To investigate the flow of primary slag bearing TiO₂ in the cohesive zone of blast furnaces,experiments were carried out based on the laboratory-scale packed bed systems.It is concluded that the initial temperature of slag dripping increases with decreasing FeO content and increasing TiO₂ content.The slag holdup decreases when the FeO content is in the range of 5wt%-10wt%,whereas it increases when the FeO content exceeds 10wt%.Meanwhile,the slag holdup decreases when the TiO₂ content increases from 5wt% to 10wt% but increases when the TiO₂ content exceeds 10wt%.Moreover,slag/coke interface analysis shows that the reaction between FeO and TiO₂ occurs between the slag and the coke.The slag/coke interface is divided into three layers:slag layer,iron-rich layer,and coke layer.TiO₂ in the slag is reduced by carbon,and the generated Ti diffuses into iron.     

手性稀土配合物在不对称催化应用中的研究进展

近年来随着光学纯化合物需求的不断增大,不对称催化逐渐成为科学研究的前沿领域之一.稀土元素则是由周期表中ⅢB族Sc、Y和镧系元素(La~Lu)的17种元素组成.相比其他过渡金属与各类配体轨道间的作用,稀土金属有其独特之处,因此,近年来手性稀土配合物在不对称催化领域的应用,也逐渐引起人们的重视.根据各类手性配体中所含配位原子的不同,对手性稀土配合物的类型及相关的不对称催化反应作简要综述.     

甘蔗提取物的抗氧化性能

膳食中的抗氧化剂有助于保护人体组织和细胞免受自由基的危害.目前,已有多种天然提取物制剂被用作膳食补充剂.文中比较了美国零售市场中4种甘蔗制品和1种玉米浆制品的组成和抗氧化能力,发现5种制品的抗氧化能力均与颜色密切相关.通过分析经不同澄清工艺并经真空浓缩的两种甘蔗汁的抗氧化能力,发现石灰澄清和纯碱澄清均不会造成抗氧化能力的显著降低.文中还对不同方法脱色后制品的抗氧化能力进行了比较.     

Computational stability of the forced dissipative nonlinear atmospheric equations

A new concept of computational quasi-stability (CQS) is introduced to study the computational stability (CS) of the forced dissipative nonlinear (FDN) evolution equations. Based on the concept, the CQS criterion of difference scheme of FDN atmospheric equations is obtained. So it provides the theoretical basis for designing the computational stable difference scheme of FDN atmospheric equations.