Simple model for gas holdup and liquid velocity of annular photocatalytic external-loop airlift reactor under both bubble and developing slug flow

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.     

Nobel Prize in Physics 2006

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.     

基础医学研究生创新能力培养的探索与实践

研究生教育侧重于创新教育,基础医学教育是研究生教育中至关重要的一部分,它不仅关系着人们的健康,而且也标志着整个国家的医疗水平。章文以延安大学医学院基础医学研究生作为实践与研究的对象,探讨了如何提高基础医学研究生的创新能力。     

Noise assisted directed motion at the molecular level — 2

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.     

The Journey Toward Transformational Learning in a Statewide Doctoral Program

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.     

化学实验室常见废弃物的处理

实验废弃物对环境的负面影响尚未引起人们应有的重视。要避免其任意排放对环境的危害，应依据绿色化学减量化、再利用、再循环的原则对其进行处理，化学实验室废气应采用溶液吸附法和固体吸收法等来处理、废水应采用中和法、萃取法、化学沉淀法、氧化还原法等来处理，实验用过的有机溶剂应进行回收与提纯。     

可持续消费及其核心理念

当今世界进入了一个高消费时代,面对高消费所带来的一系列消费伦理问题,人们开始倡导向新的消费模式———可持续消费模式转变。可持续消费的核心理念就是:绿色、适度、健康。同时,它还具有规范个人生活消费和反对个人生活消费中铺张浪费现象的作用。     

陕西省商品粮基地县建设的思考

对陕西省商品粮基地县建设的分析表明，该省商品粮基地县数量自1984年的20个增至2000年的38个，其粮食作物播种面积与粮食产量则呈波动性上升。商品粮基地县在地域分布上主要集中于关中平原，其次是汉中盆地，黄土高原及陕南秦巴山地呈零星分布。随着“人粮矛盾”的日益突出，务必加大对关中平原和汉中盆地商品粮基地县的建设力度，并在自然生态条件有所改善的延安、安康等市开拓新的商品粮基地县。     

Predictors of College Attendance Patterns of Rural Youth

This study investigated patterns of college attendance using data from a nationwide and contemporary sample of 2112 rural youth. We found that more than half of rural youth attended two-year institutions at some point during their college career and about a fourth initially enrolled in a two-year college before enrolling in a four-year college. Results also revealed that parental education, college preparatory track and preparation experiences, and teacher expectations predicted students’ college attendance patterns. Our findings point to the importance of two-year colleges and highlight the influence of family characteristics and students’ schooling experiences in the postsecondary trajectories of rural youth.