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251.
252.
近年来,高等教育内外部环境发生着深刻的变化,高校面临一系列新挑战。高等教育要以可持续发展为目标,高校战略联盟是高校持续发展的有效途径,通过高校战略联盟实现资源共享、风险共担、相互促进、共同发展的合作机制,进而有效提高我国高校的核心竞争能力。  相似文献   
253.
本文对人参皂甙20(s)-原人参三醇组中的几种主要单体皂甙在近似胃液条件下的酸水解产物,以HPLC法进行了分析检测,结果表明:人参皂甙Rg_1降解产生次级Rh_1;Re产生Rg_2;和预料相符,水解时这些次级甙均伴生少量C_(20)异构体。  相似文献   
254.
目的:研究不同剂量的利巴韦林对小鼠生长发育和小肠组织形态结构的影响。方法:30只1月龄小鼠随机分为3组,对照组灌胃生理盐水,低、高剂量利巴韦林组分别按照5mg/kg、10mg/kg体重灌胃药物,连续用药14d,每周清晨称重,采集血液和组织样品。结果:利巴韦林能够提高小鼠日增重,且低剂量用药7d的促生长效果明显(P0.05)。给药14d后,低剂量组脾脏指数比高剂量组显著增加(P0.05)。与对照组相比,高、低剂量利巴韦林组红细胞数下降,白细胞总数增加,中性粒细胞数量极显著降低(P0.01),淋巴细胞数量极显著升高(P0.01),低剂量组白细胞总数极显著增加(P0.01)。高剂量利巴韦林破坏了小肠黏膜上皮形态结构,抑制了小肠绒毛发育;而低剂量利巴韦林能够提高小肠绒毛长度、隐窝深度、十二指肠绒毛长度和隐窝深度比值,增强小肠功能的发挥。结论:利巴韦林具有促进机体生长发育和调节免疫功能的作用,但随着添加剂量的增加,利巴韦林的促生长和免疫增强效果减弱。在临床应用上,应注意根据不同的个体来确定利巴韦林的适宜添加剂量和合理应用时间。  相似文献   
255.
Based on the momentum conservation approach, a theoretical model was developed to predict the superficial liquid velocity, and a correlation equation was established to calculate the gas holdup of an annular external- loop airlift reactor(AELAR)in the bubble flow and developing slug flow pattern. Experiments were performed by using tap-water and silicone oil with the viscosity of 2.0 mm2/s(2cs-SiO)and 5.0 mm2/s(5cs-SiO)as liquid phases. The effects of liquid viscosity and flow pattern on the AELAR performance were investigated. The predictions of the proposed model were in good agreement with the experimental results of the AELAR. In addition, the comparison of the experimental results shows that the proposed model has good accuracy and could be used to predict the gas holdup and liquid velocity of an AELAR operating in bubble and developing flow pattern.  相似文献   
256.
试论现代陶艺的设计意念   总被引:1,自引:0,他引:1  
陶艺在制作前必须有一个想象,这时陶艺设计的意念就产生了。在意念的指导下,赋予材料以特定的存在形式,使其成为具有一定审美价值的陶瓷艺术作品。在现代设计潮流的影响下,现代陶艺设计呈现出夸张、寓意、怪异的视觉特征,给人以视觉冲击,现代陶艺所表现的倾向是艺术家“自我”的内心世界,是“心理”的写实。  相似文献   
257.
The discovery of the cosmic microwave background radiation in 1965 was a defining moment in the history of cosmology — the science that deals with the universe as a whole, its origin, evolution and future. This discovery was recognized with Nobel Prizes to Penzias and Wilson in 1978. The Nobel Prize in Physics for 2006 further acknowledged the importance of the study of this background radiation. The precise measurement of the spectrum of this radiation and its variation across the sky have helped our understanding of the evolution of structures in the universe. This article explains these discoveries and their importance. T Padmanabhan is a professor at IUCAA, Pune. He is interested in all aspects of theoretical physics, and especially in those in which gravity plays a role.  相似文献   
258.
The term noise is used to describe fluctuations about the mean deterministic stationary value of a physical quantity. It is now being increasingly realised that noise is an important ingredient to bring order in dynamical processes. Though it appears counterintuitive, noise seems to help in directing transport processes in biological systems at the molecular level. In Part 2 of the article, we discuss some more examples of noise assisted directed motion.  相似文献   
259.
This article describes strategies for redesigning the University of Missouri's Statewide Cooperative Ed.D. Cohort Program in educational leadership. Results had suggested a need to redesign aspects of the program in order to achieve higher levels of cognitive learning outcomes inclusive of transformational learning. To help meet this objective, the areas targeted for redesign were the curriculum as it relates to issues of diversity and ethics, instruction as it relates to group dynamics and cohort models, and increased time and a forum for students to reflect on their leadership practices. This forum also allowed faculty to monitor and assess the transformational learning outcomes of their students. This article is meant to assist others who are interested in fostering higher levels of transformational learning outcomes within their programs. Meredith L. Mountford holds a Bachelor of Science degree from Illinois State University, a Master of Science degree in educational administration from Northern Illinois University and a Philosophy of Science degree in educational administration from the University of Wisconsin—Madison. She is an Assistant Professor and has served as Director for the Statewide Cooperative Ed.D. Cohort Program in educational leadership at the University of Missouri—Columbia.  相似文献   
260.
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