亚麻籽油中药软胶囊的30天大鼠喂养试验研究

通过亚麻籽油与中药天然产物复配得到了一种具有缓解视疲劳作用的软胶囊。为了评价该软胶囊的安全性,对该样品进行30d大鼠喂养试验。试验结果显示,各试验组大鼠体重、进食量、食物利用率、血常规、脏体比及病理组织学观察等各项指标与阴性对照均无显著性差异。因此亚麻籽油中药软胶囊属无毒级,可开发成为高附加值保健食品。     

多点电喷天然气汽车发动机进气干涉现象的数值解析

首先采用多维数值模拟的方法解析了从天然气喷射阀喷出的突发天然气喷流的发展过程,并由纹影试验验证了这个数值解析方法的可行性。在此基础上,解析了单进气阀和双进气阀发动机进气歧管内天然气的喷射和反射过程。结果表明,大量天然气与进气阀冲突后向进气歧管入口方向反射并造成进气阀附近气体压力升高;若进气歧管较短时,天然气-空气混合气反射到歧管入口并造成各缸混合气分配不均匀是完全可能的;即使较长的进气歧管时,由于发火顺序不同,各缸间的进气干涉程度也不一样,这将引起各缸实际的进气充量发生变化。     

Relative Availability of Tannin- and Terpene-containing Foods Affects Food Intake and Preference by Lambs

The availability of different forages varies across landscapes, but little is known about how proportional consumption of different foods affects food intake and the use of landscapes. The relative amounts of nutrients and plant secondary metabolites (PSM) consumed by herbivores may influence forage intake and animal fitness in landscapes dominated by plants with PSM. Our objective was to determine if the relative availability of nutritious foods that contain PSM affected food preference and intake by lambs. Lambs in three treatments (eight lambs/treatment) were offered two PSM-containing foods at different relative availabilities: treatment 1—ad libitum terpene- and 100-g tannin-containing food, treatment 2—ad libitum tannin- and 100-g terpene-containing food, and treatment 3—ad libitum access to both tannin- and terpene-containing foods. We measured intake of individual foods and total intake of PSM-containing foods during conditioning and a preference test, where animals were offered both PSM-containing foods ad libitum. When lambs were fed 100 g of the tannin-containing food, they ingested more terpene and total PSM (P < 0.05) than when both PSM were offered ad libitum, but limiting terpenes did not affect intake of tannin or total intake of PSM (P > 0.10). During preference tests, all groups preferred tannins over terpenes, but lambs in the treatment fed 100 g of tannin had a higher preference for terpenes than did lambs in the other two treatments (P < 0.10). These results support the notion that the relative amounts of PSM consumed affects intake and preference for PSM-containing foods by herbivores.     

与1990年ICRP推荐接轨的内照射剂量估算方法研究及其软件的开发

介绍用于估算个人内照射剂量的新一代计算机应用软件系统。该系统参照ICRP第56、66、67、68、69、71、78号等一系列出版物提供的代谢模型和参数,采用了适于在微机上实现的矩阵算法,使用VC 编制而成,可在Win95或更高版本的微软操作系统下运行。它可以将个人内照射监测量换算为摄入量、有效剂量和其它评价量,适用于职业受照人员的常规个人内照射剂量估算。本套软件采用了新的模型和参数,可以直接求解任何不循环的和循环的库模型。这使得它可用于与1990年ICRP推荐和1997年的国际电离辐射防护和辐射源安全的基本安全标准接轨的个人内照射剂量管理和估算。此外,本套软件在视窗操作系统下运行,图形界面使得它给用户的感觉更加舒服,使用更加方便。     

A study on the deposit formation in the cylinder and intake valve of a S. I. Engine

A spark ignition engine with port fuel injection (P.F.I.) system was used to accumulate cylinder head deposit (C.H.D.), intake valve deposit (I.V.D.), and piston top deposit (P.T.D.) on an engine dynamometer. In this study, the effect of base gasoline on I.V.D. was examined. The deposit forming tendency and the influence of the fuel component for decreasing deposits have been experimentally examined. The amount of I.V.D. has been observed to increase linearly with the engine operating time. It is also observed that the amount of valve deposit with newly blended gasoline is less than that with base gasoline.     

高原地区柴油机进气系统改造与性能分析

通过对Ｓ１９５柴油机进气管内压力波形的测试,分析了进气管长度对充气性能的影响。论证了不同海拔下最佳进气管长度相等的规律,确定了适宜各种工况的进气管长度。在对最佳进气管转速适应性试验和滤清器对进气管惯性效应影响分析的基础上,肯定了进气管改造对改善高原地区柴油机工作性能的积极意义。     

进气迟后角对四冲程发动机性能影响的分析

充量系数是影响发动机性能的主要因素。主要阐述了进气迟后角对四冲程发动机充量系数的影响,对四冲程发动机的充量系数进行了定义并推导了充量系数的解析式,充量系数解析式包含了多个影响因素,各因素之间的相互影响、相互关连。从不同角度总结提出了合理的确定进气迟后角的方法,从而提高充量系数,改善发动机的性能。     

轻型客车进气系统噪声优化设计分析

本文通过一款轻型客车进气系统噪声优化设计的案例,详细介绍了轻型客车进气系统气动噪声、结构辐射噪声的优化过程和分析方法,提出了一些进气系统设计过程中需要关注的方向,对进气系统的噪声控制和结构改进具有一定的指导作用。     

某增压汽油机进气过程流体流动特性研究

本文采用瞬态可压缩黏性流体微分方程和标准双方程紊流模型对某增压汽油机进气过程的流体流动特性进行数值模拟,计算结果表明:缸内瞬时温度和压力的变化,主要受到气缸内壁和新鲜充量传热以及活塞运动的影响,而进气道内瞬时温度的变化与进气道内气流运动的湍流强度密切相关,因此,要提高该汽油机的充量系数,最合理的办法是抑制进气道内的湍流强度。