Gas chromatographic analysis of fragrances in palm-based white soaps

Four commercial soap fragrances 1,2,3, and 4 were incorporated in palm-based white soaps and made into bars. The soap bars were stored at 25°C and 40°C for three months. The headspace gas-chromatographic volatiles, fragrance odor intensity and whiteness analyses of the soap samples were carried out at 10-day intervals. By means of gas chromatography and mass spectrometry, some of the headspace gas-chromatographic peaks were identified. These peaks were useful in monitoring the fragrance components. For example, fragrance 4 contains the components limonene and citronellal which are known to possess a citrus odor component. Fragrance odor intensity scores showed that the intensity of the fragrances in the soap base was the same for all. Results also showed that most of the fragrances had the same effect on the whiteness of palm-based white soaps, except for fragrance 2 which gave a pink color to the white soaps. Equations were established between the fragrance odor intensity and area under the gas-chromatographic peaks. The equation can give useful information on the fragrance odor intensity by calculating the area of the chromatographic peaks; the fragrance odor intensity is a reflection of the fragrance retention in palm-based soaps.     

Mssbauer 谱仪数据接口的改进

对Ｍｏｓｂａｕｅｒ谱仪数据接口进行了改进。通过简化电路，以软件实现硬件的功能。在测量中省却了单道分析器，使测量系统更为简单、可靠和高效。     

振荡限幅器型卫星电视接收解调器

本文着重介绍了振荡限幅器型门限扩展解调器的工作原理及工作条件,同时设计了一种振荡限幅器型卫星电视接收解调器。该解调器具有电路简单,性能良好,具有较低接收门限等特点,可用于接收苏联714MHz卫星电视节目。此解调器特别适用于一些接收场强较弱的地区。实验表明,该解调器门限改善量约可达3dB。     

多级安全关系数据库系统审计功能的设计

本文简要地介绍了多级安全关系数据库系统和计算机系统的审计，强调指出了多级安全关系数据库系统审计功能的设计必须遵循多级安全策略，并就审计粒度的选择，审计开关和阈值的设置，审计日志的维护和查询等方面的设计作了详细的讨论。     

低渗透油藏超前注水理论及其应用

低渗透油藏最显著的特征是存在启动压力梯度和介质变形现象,这使其在开发过程中渗流阻力增大、单井产量降低,递减速度加快,稳产难度加大,并降低最终采收率。对低渗储层启动压力梯度和介质变形进行了物理模拟实验,定量描述了两者的非线性变化规律,分析了介质变形对储层物性参数的影响。通过室内实验、渗流理论、数值模拟以及矿场试验研究,建立了低渗透油藏非线性渗流数学模型,提出了在超前注水期运用保持合理地层压力水平、注水压力、注水强度和注水时机的开发技术,在长庆等低渗透油田现场应用后取得较好的开发效果,提高单井产量15%~20%。     

PREDICTING THE EFFECTS OF LOAD RATIO ON THE FATIGUE CRACK GROWTH RATE AND FATIGUE THRESHOLD

The effect of the load ratio, R, on fatigue crack growth behaviour is analysed on the basis of the recently proposed inelastic discrete asperities model. A wide range of load ratios, both positive and negative, are examined. Particular emphasis is placed on compressive excursions, i.e. negative R loadings. The inelastic discrete asperities model is a micro-mechanical analysis based on the plastic crushing of a single asperity (or multiple asperities) located on the crack face close to the crack tip and under dominantly plane strain conditions. Experimental data have indicated that the primary crack face contacts which obstruct closure are immediately adjacent to the crack tip, although segments of the crack face more distant from the crack tip are not neglected. However, the more distant asperities are a part of the past crack advance history which does not influence current behaviour. By use of this model, it is shown that the effect of the load ratio can be adequately predicted once some baseline information on mechanical material properties and surface roughness is provided. The model also provides useful trend information and explains many of the observed phenomena, e.g. the ‘saturation’ of the compressive underload effects. For a constant applied nominal stress intensity factor range, ΔK_nom , it is shown that the effective stress intensity factor range, ΔK_eff , initially decreases as the positive R decreases (corresponding to the increasing influence of closure), reaches a minimum around R = 0, and then starts increasing with negative R (corresponding to the plastic crushing of the asperities which reduces closure), eventually reaching a saturation level below ΔK_nom . Conversely, for an assumption of a constant ΔK_eff , the applied ΔK_nom increases as the positive load ratio decreases, reaching a maximum around R = 0, and then decreases with more negative R values, eventually reaching again a saturation level (above ΔK_eff ). It is also shown that the effect of material hardness can be directly analysed based on this model.     

KDP晶体激光损伤的研究

报道了散射颗粒、焦斑面积和非线性吸收等对ＫＤＰ晶体激光损伤的影响。研究了ＫＤＰ晶体的多脉冲损伤。     

三峡建库后芦家河水道的演变预测

针对长江中游芦家河河段的特性，建立了适合该河段的平面二维水流数学模型，用芦家河水道的实例资料验证表明，计算值在水位，流速，流向等方面与实例情况一致，说明该模型能够较好地反映芦家河水道的水流运动特性。     

面阵CCD图像传感器点破坏机理研究

用１．６μｍ脉冲激光聚焦辐照面阵ＣＣＤ图像传感器。遭破坏面积不到有效传感器面积的万分之一，整个ＣＣＤ图象传感器无图像输出。破坏阈值小于１２Ｊ／ｃｍ２。分析了破坏机理。