纳米金属氧化物去除水体重金属的研究进展

简要介绍了用于吸附水体重金属的几种纳米金属氧化物,包括:纳米铁氧化物、纳米锰氧化物、纳米铝氧化物、纳米钛氧化物、纳米锌氧化物、纳米镁氧化物、纳米铈氧化物以及纳米金属氧化物复合材料,讨论了各种纳米金属氧化物处理水体重金属的优缺点,并展望了其应用前景。     

天然橡胶纳米改性技术研究进展

纳米粒子和纳米复合技术在天然橡胶改性中的应用,赋予了天然橡胶纳米复合材料优异的综合性能,已成为材料科学领域研究的热点。文章综述了几种纳米材料,包括纳米粘土、纳米炭黑、纳米白炭黑、纳米碳酸钙、纳米氧化锌、碳纳米管、纳米晶纤维素、纳米二氧化钛改性天然橡胶的研究进展,并提出了天然橡胶纳米复合材料的发展趋势。     

纳米材料改性聚酰亚胺研究进展

介绍了纳米Al_2O_3、纳米SiO_2、纳米TiO_2、纳米MgO、纳米ZnO、纳米BaTiOO_3、倍半硅氧烷(POSS)、石墨烯和碳纳米管改性聚酰亚胺(PI)的研究进展,综述了各种纳米粒子的改性效果,其中纳米Al_2O_3、纳米SiO_2、纳米TiO_2、纳米MgO、纳米ZnO、纳米BaTiO_3对PI的改性研究主要集中在热性能、电学性能、力学性能等方面;石墨烯和碳纳米管改性PI具有优良的导电性;POSS使PI的抗氧化等性能有显著的改善。分析了偶联剂对改性薄膜性能的影响,并对今后纳米改性PI的发展趋势进行了展望。     

全球石化领域中纳米科技产业化现状

针对国内外纳米科技发展现状 ,阐述了纳米技术市场、各国研发投资以及在石油化工领域的研发和应用成果 ,包括碳纳米管、纳米催化剂、纳米复合材料 (纳米轮胎、纳米塑料、纳米纤维 )、纳米 /聚合物膜、纳米润滑油和燃油添加剂 ,并对我国纳米科技产业化现状提出了发展建议     

无机纳米粒子改性聚氨酯弹性体的研究进展

介绍了用无机纳米粒子改性聚氨酯弹性体的制备方法,综述了纳米Si O2、纳米Zn O、纳米蒙脱土、纳米Ca CO3、纳米Ti O2、碳纳米管以及其他无机纳米粒子改性聚氨酯弹性体的研究进展,指出了无机纳米粒子改性聚氨酯弹性体目前存在的问题。     

纳米陶瓷及其纳米复相陶瓷的研究现状

综述了纳米陶瓷和纳米复相陶瓷的的研究现状．探讨了纳米陶瓷的力学性能及其热喷涂纳米陶瓷涂层存在的问题．分析了纳米复相陶瓷的增韧机理，为纳米陶瓷的研究和应用提供了理论依据。     

聚合物纳米纤维技术的新进展

重点介绍了静电纺丝技术发展现状,详细介绍了双组分聚合物纳米纤维、碳纳米纤维、聚偏氟乙烯纳米纤维、生物可降解聚合物纳米纤维的制备和性能,展望了聚合物纳米纤维及纳米纤维膜产品的应用。     

纳米材料在涂料改性中的应用

介绍了纳米改性涂料的优点,重点叙述了纳米SiO2、纳米TiO2、纳米CaCO3在涂料中的应用,并提出了纳米改性涂料发展中存在的一些问题。     

纳米磁性材料的制备及应用的新进展

介绍了纳米磁流体、纳米磁性颗粒、纳米磁性微晶及纳米磁性复合材料的制备方法并比较了各种方法的优缺点。并对纳米磁性材料的应用进行了概述,对其研究前景进行了展望。     

纳米吸波材料的研究现状与发展趋势

评述了纳米吸波材料的特性及吸波原理,介绍了纳米铁氧体吸波材料、纳米金属吸波材料、纳米陶瓷吸波材料、纳米导电高分子吸波复合材料、碳纳米管吸波材料、纳米复合吸波材料研究现状及发展情况,指出了纳米复合吸波材料是未来纳米吸波材料的研究重点。     

Phthalyl chitosan–poly(ethylene oxide) semi‐interpenetrating polymer network microparticles for oral protein delivery: An in vitro characterization

Polyhydroxybutyrate (PHB) is generally considered to be a very uneasy biopolymer to handle because of significant instability during melt processing and some excessive brittleness. This work studied the morphological, thermal, and barrier properties of novel melt-mixed nanobiocomposites of PHB, poly(ε-caprolactones) (PCL), and layered phyllosilicates based on commercial organomodified kaolinite and montmorillonite clay additives. The addition of PCL component to the blend was seen to reduce oxygen permeability but it was also found to lead to a finer dispersion of the clay. The addition of highly intergallery swollen organomodified montmorillonite clays to the PHB blend led to a highly dispersed morphology of the filler, but this simultaneously increased to a significant extend the melt instability of the biopolymer. Nevertheless, the organomodified kaolinite clay, despite the fact that it was found to both lead to less dispersed and irregular morphology, particularly for higher clay loadings, it led to enhanced barrier properties to oxygen, D -limonene, and water. D -limonene and specially water molecules were, however, found to sorb in both hydrophobic and hydrophilic sites of the filler, respectively, hence diminishing the positive barrier effect of an enlarged tortuosity factor in the permeability. Mass transport properties were found to depend on the type of penetrant and modeling of the permeability data to most commonly applied formalisms was not found to be satisfactory because of factors such as morphological alterations, heterogeneity in the clay dispersion, and penetrant solubility in the filler. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Nutrition in the sport practice: adaptation of the food guide pyramid to the characteristics of athletes diet

In spite of all the advances in sport nutrition and the importance of an adequate food intake in order to improve sport performance, both recreational and professional athletes forget frequently to include planning an optimum diet and fluid intake in their global strategy for performance. Physiological and metabolic adaptations produced as a consequence of physical exercise lead to the necessity of increasing caloric (in accordance to energy output) and protein (based on the trophic needs of the organism) intake. Likewise, paying major attention to vitamin and mineral intake, specifically B vitamins and zinc and chromium, is required, in order to optimize carbohydrate metabolism, the ultimate limiting factor for sport performance. During the training phase, 60% of calories should come from carbohydrates, protein intake should be 1.2-2 g/kg/day and athletes should follow the recommendations of the food guide pyramid. During the pre-, per- and post-competition phase the healthy aspect of the diet passes to a second level, in order to obtain good sport performance and to guarantee a fast and effective recovery. Again, carbohydrates with a high or medium glycaemic index and water are the nutrients which have to be calculated more thoroughly. In conclusion, athletes have to follow a diet that is adequate to their higher energy output and to their higher metabolic turnover. The food guide pyramid is a graphic expression which facilitates the comprehension and following of a healthy diet. In the present article, the authors introduce the pyramid adapted to the characteristics of sports nutrition, with easy-to-follow practical recommendations regarding the kind and amounts of foodstuffs that should be consumed in order to cover nutrient needs of people who exercise regularly.     

5种新型杀菌剂对4种鱼的急性毒性及安全性评价

为评价5种新型杀菌剂的环境安全性,采用半静态法测定了其对4种鱼的急性毒性。结果表明,氟醚菌酰胺对斑马鱼、稀有鮈鲫和凤尾鲫的LC_(50)(96 h)均大于100 mg/L,对青鳉的LC_(50)(96 h)为35.25 mg/L,其急性毒性均为低毒;氟吡菌胺对斑马鱼、青鳉、稀有鮈鲫和凤尾鲫的LC_(50)(96 h)分别为1.49、0.56、0.35、1.04 mg/L,其对斑马鱼和凤尾鲫急性毒性为中毒,对青鳉和稀有鮈鲫为高毒;苯噻菌胺对斑马鱼、稀有鮈鲫和凤尾鲫的LC_(50)(96 h)均大于100 mg/L,对青锵的LC_(50)(96 h)为88.23mg/L,其急性毒性均为低毒;嘧菌酯对斑马鱼、青鳉、稀有鮈鲫和凤尾鲫的LC_(50)(96 h)分别为106.80、0.44、85.96、4.61 mg/L,其对斑马鱼和稀有鮈鲫急性毒性为低毒,对青鳉急性毒性为高毒,对凤尾鲫为中毒;醚菌酯对斑马鱼、青鳝、稀有鮈鲫和凤尾鲫的LC_(50)(96 h)分别为0.77、0.66、0.51、0.81 mg/L,其对4种鱼急性毒性均为高毒。明确这些药剂的环境安全性对指导其科学使用,保护环境生物均有较大意义。     

Major Trends in Refractories Industry at the Beginning of the 21st Century

An analysis of the present and of the future of the refractories industry is being presented,considering some improtant techincal,economical,human and environmental issues,on a worldwide basis,Refractories still needed as confinement materials to prevent heat and mass transfer losses in many diverse manufacturing industries,and will remain so ,but the main challenges,this industry do need to neet,are to adjust to and overcapacity production ,to cope with new needs of the customers,in particular the “outsourcing“,which is a new custome/supplier rela-tionship being adopted by many of them,and more compet-itive arena.Among the direct consequences,are the need to keep the education world in refractory engineering training aliver and to cope with macro and micro projects to change the image of the Refractories,from a commodity material to a sophisticated “high-tech“ compostie material.Some suggestions are provided in the text.     

尿素设备腐蚀的影响因素分析及防腐措施

针对尿素生产的特点,分析了对尿素设备腐蚀的影响因素:介质温度、氨碳摩尔比、水碳摩尔比、氨基甲酸铵溶液浓度、氧含量、硫含量、氯离子含量和介质流速等。提出了正常生产和停车封塔2种情况下的防腐措施。正常生产期间要严格控制如下指标:操作温度、系统的加氧量、硫含量、氯离子含量、氨碳比和水碳比;停车期间要严格控制系统的氨碳比和水碳比,同时根据不同状况来确定停车封塔时间。     

提高学生综合与创新能力多种教学方式的探索

以《材料化学》、《复合材料》、《材料现代分析技术》和《材料导论》等专业课为载体,结合高分子科学与工程系科研优势和资源,探索启发式、参与式和专题讨论课等多种教学方式,将其应用到专业课教学中,以提高学生综合与创新能力为目标进行教学研究与实践。在理论课教学上注重思维训练,传授学习方法,提高学生学习自主性;注重课程之间对学生综合能力培养的协同作用。鼓励学生开拓思路,鼓励创新,配合教师完成每个教学环节,由此加深学生对课程知识的理解,有效地提高综合能力。     

生成兴趣的大学教学

大学教育不仅仅是教给学生课本上的知识,更重要的是教会他们学习的方法,如何去获取有用的知识,以及如何利用所学的知识去解决实际问题。如何培养大学低年级学生的学习兴趣,如果引导他们主动去学习,在化学实验课上,又如何主动细致的去完成动手部分的学习,将是我们大学教学工作中急需要改进和提高的重要部分。     

Impact of ammonia fiber expansion (AFEX) pretreatment on energy consumption during drying,grinding, and pelletization of corn stover

Pretreatment and densification of biomass can increase the viability of bioenergy production by providing a feedstock that is readily hydrolyzed and able to be transported over greater distances. Ammonia fiber expansion (AFEX?) is one such method targeted for use at distributed depots to create a value-added and densified feedstock for bioenergy use. However, the pretreatment process results in a high-moisture material that must be dried, further size reduced, and pelletized, all of which are energy-intensive processes. This work quantifies the energy consumption required to dry, grind, and densify AFEX-pretreated corn stover compared to non-pretreated stover and explores the potential of reduced drying as a means to conserve energy. The purpose of this work is to understand whether material property changes resulting from AFEX pretreatment influence the material performance in downstream formatting operations. Material properties, heat balance equations, and a rotary drum dryer model were used to model a commercial-scale rotary drum dryer for AFEX-pretreated corn stover, showing the potential to reduce dryer energy consumption by up to 36% compared to non-pretreated corn stover. Laboratory-measured grinding and pelleting energies were both very sensitive to material moisture content. Overall, the total energy required for drying, grinding, and pelleting amounts to a savings of up to 23 kWh/dry Mg for the AFEX-pretreated material when dried to a low moisture content, equating to up to 0.61 $/Mg savings for gas and electricity. Grinding and pelleting of high-moisture AFEX-pretreated stover was shown to be more costlier than the savings collected through reduced drying. Although the energy and cost savings shown here are modest, the results help to highlight operational challenges and opportunities for continued improvement.     

中国基础磷化工产业现状与展望

以磷肥、黄磷、热法磷酸、三聚磷酸钠、饲料磷酸氢钙等产品为例,阐述了基础磷化工产业现状,针对基础磷化工产品同质化、技术等同化、市场过剩的局面,分析了产生问题的原因。指出基础磷化工必须淘汰落后产能,必须依靠技术进步降低生产成本,实现产品结构的升级与调整;而技术进步的重点在于实现原子经济效益、能源利用和劳动生产效率三者的最大化以及消耗的最小化,要不断开发满足社会需求的新产品。此外,还对相关的政策法规和规章制度提出建议。     

C50渡槽高性能混凝土耐久性研究

基于渡槽混凝土病害严重、耐老化性能差等问题,采用萘系和聚羧酸盐两种高效减水剂,根据不同水胶比、粉煤灰掺量、粉煤灰矿粉复掺配制出C50渡槽高性能混凝土,并测试混凝土的抗氯离子扩散系数、抗冻性和抗碳化性能等耐久性指标,分析水胶比、粉煤灰掺量、粉煤灰矿粉复掺对其耐久性的影响。结果显示:随着粉煤灰掺量增加,混凝土的抗氯离子渗透性能有所提高,但抗冻性能和抗碳化性能均呈下降趋势;粉煤灰矿粉复掺提高了混凝土的抗氯离子渗透性能和抗碳化性能,抗冻性略有降低。