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951.
论校园文化和德育目标的一致性 总被引:3,自引:0,他引:3
冯峰 《河南机电高等专科学校学报》2002,10(1):13-14
中系统介绍了校园化和德育目标的关系,并找准两之间的结合点,通过分析两的一致性和辩证统一关系,达到育人目的。 相似文献
952.
活性炭单柱提取肌苷新技术研究 总被引:1,自引:0,他引:1
活性炭单柱提取肌苷新技术研究李永泉,张进,姚恕,郑莲英,俞峰(杭州大学生物系杭州310028)(浙江大学化工系杭州310027)关键词:肌苷,提取技术,活性炭单柱1前言目前,国内肌苷发酵后处理工艺落后,在分离提取工序中肌苷损失严重,收率一般只有50%... 相似文献
953.
本文介绍两种利用低轨地理卫星星座进行移动通信的系统。一种是英法联合研究提出的利用24颗低轨卫星组成的移动通信;另一种是美国研究提出的利用192颗低轨卫星组成的移动通信系统。最后将低轨卫星移动通信系统与同步卫星移动通信系统及高轨卫星移动通信系统进行了比较。 相似文献
954.
D. P. Dreoni D. Pinelli F. Trifirò Z. Tvaruzkova H. Habersberger P. Jiru 《Catalysis Letters》1991,11(3-6):285-294
The catalyst behaviour of titanium silicalite, which was found the most active and selective catalyst for liquid-phase ammoximation of cyclohexanone to the corresponding oxime with hydrogen peroxide, was investigated in the gas-phase ammoximation with molecular oxygen in and compared with those of pure silicalite and samples of vanadium and chromium silicalites. The results showed that Ti-silicalite is a selective catalyst not only in the reaction with hydrogen peroxide but also in the reaction with molecular oxygen. However, a big limitation was found in the poor activity of the silicalites which do not allow to reach high oxime yields. 相似文献
955.
Results from long-term field experiments in south-western Australia are presented in the form of relationships between yield, expressed as a percentage of the maximum yield, and soil test for phosphorus (P) values. Maximum yields were not always indicated by well defined yield plateaux. Different methods have been used to estimate the maximum yield value which is used to calculate yield as a percentage of the maximum yield so as to remove interseasonal variation. For all of these methods and for the same site, the same P fertilizer (superphosphate), and the same plant species, the relationship between yield and soil test P differed for different years. Consequently fertilizer recommendations based on the assumption that this relationship is constant are likely to be incorrect. We therefore question the validity of the common practice in soil testing programmes of using percentage yield values to remove interseasonal variation. 相似文献
956.
焦炉装煤烟尘治理的烟气量计算 总被引:2,自引:0,他引:2
通过对焦炉装煤烟尘治理的烟气量计算和研究,提出不同治理系统的烟气量计算方法及应采取的措施。 相似文献
957.
D. Bergmann U. KaiserS. Wagner 《Journal of Wind Engineering & Industrial Aerodynamics》2003,91(4):543-550
The determination of dynamic wind loads on buildings, i.e. pressure and deflection, has gained increasing interest (European Prestandard ENV 1991-2-4, Eurocode 1: basis of design and actions on structures—Part 2-4: actions on structures—wind actions, European Committe for Standardization, Brussels, 1995; DIN 1055 Teil 4 Lastannahmen für Bauten, Verkehrslasten, Windlasten bei nicht schwingungsanfälligen Bauwerken, 1991; N. Hölscher, M. Hortmanns, J. Sahlem, Praxisnahe Erfassung von Windwirkung an Industrie- und Hochbauten, Windwirkung im Bauwesen, Braunschweig, 7, Dreiländertagung D-A-CH 2001, Windtechnologische Gesselschaft, 2001 [1], [2] and [3]). Therefore, the spectral distributions of velocity and pressure fluctuations in wind tunnels are an important quality aspect. While velocity fluctuations can be manipulated by the obstacles used to create the turbulence, pressure fluctuations are influenced by acoustic noise as well. Especially, the first eigenfrequency of the longitudinal mode of the wind tunnel tends to disturb the pressure spectrum.In this paper, a solution for the reduction of low-frequency acoustic pressure fluctuation is presented and its application in the atmospheric boundary layer wind tunnel at the IAG is shown. 相似文献
958.
保证跌落试件姿态的方法 总被引:1,自引:1,他引:0
进行包装件的自由跌落试验时,必须保证试件姿态符合标准规定。笔者在实践中总结出一种保证试件姿态和检验试件姿态误差的具体方法。 相似文献
959.
When freshly etched samples of various types of copper were exposed in moderately acid, aerated chloride solutions, two phenomena were observed. First the corrosion potential and the pH of the solution decreased over a shorter time, then the potential increased over a long period (600-1500 min), following an s-shaped pattern. Increase in pH during the second stage was avoided using a pH-stat. The corrosion rate increased little or not at all over the entire period. A tentative interpretation of the short-term behaviour is presented with some reservation. The long-term development of the potential suggests phase formation or transformation following the Avrami pattern. By suitable derivations it was possible to fit the development of potentials to the Avrami equation. Subsequent examinations by Auger spectroscopy proved the presence of thin layers of Cu2O on the copper surfaces, increasing in thickness with exposure time. The dissolution kinetics can be described in terms of two parallel electrochemical reactions and a simultaneous non-electrochemical dissolution reaction. 相似文献
960.
用激光外差测振装置测量了扬声器纸盆振动幅度与激励电压及激励频牢之间的关系。为扬声器结构及振动特性的研究提供了一种精度高、重复性好的可靠测量方法。 相似文献