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51.
生态环境友好型混凝土的研究现状与展望   总被引:19,自引:5,他引:19  
分析探讨了混凝土对环境造成的危害,为实现可持续发展,必须开展生态环境友好型混凝土的研究。介绍了三类生态环境友好型混凝土的组成、结构和性能,提出了这种混凝土新材料今后的研究方向,是将粉煤灰等工业废渣的治理与生态环境治理和保护结合起来。  相似文献   
52.
This article takes a brief look at the history of modern Central European planning, especially spatial planning in Czechoslovakia. It is primarily focused on urban and regional planners, planning ideas, concepts, and projects that can be considered ‘organic’. Several important planners (all males) who kept pace with the most current European and US trends (e.g. Vladimír Zákrejs, Jind?ich Kumpo?t, Bohuslav Fuchs, Alois Miku?kovic, Ladislav ?ák, Karel Honzík, and Emanuel Hru?ka) are discussed. The text also mentions some of the driving forces of the time, which had a fundamental impact on organic approaches in planning, including the institutionalization of urban and regional planning. Attention is also given to various international influences and the transfer of ideas that have not yet been adequately analysed. In conclusion, there are some reflections on the significance of organic modernity that succinctly express the atmosphere of that time as well as the efforts of the mentioned planners and thinkers. The main message is to show the close connection between early modern urban planning and the phenomenon of organicism, or rather, organic modernity.  相似文献   
53.
Herein it is demonstrated that electrohydrodynamic co-jetting is not limited to Janus-type particles, but can also be used for the preparation of core/shell particles. Using side-by-side flow of miscible polymer solutions, electrohydrodynamic co-jetting offers an elegant and scalable route towards preparation of core/shell particles with otherwise difficult-to-prepare particle architectures, including particles with hydrophilic shell and core. Throughout this study, electrohydrodynamic co-jetting of aqueous solutions consisting of a mixture of PAAm-co-AA and PAA is used, and a range of different types of particles with distinct compartments are observed. Transition from Janus particles to core/shell particles appears to be caused by changes in the relative conductivity of the two jetting solutions. After crosslinking, the core/shell particles are stable in aqueous solution and exhibit reproducible swelling behavior while maintaining the original core/shell geometry. In addition, the pH-responsiveness of the particles is demonstrated by repeatedly switching the environmental pH between 1.3 and 12. Moreover, the core/shell particles show surprising uptake selectivity. For instance, a 450% increase in uptake of 6-carboxyfluorescein over rhodamine B base is found.  相似文献   
54.
中国石油化工股份有限公司抚顺石油化工研究院开发了一种以单质硫为主要原料的硫化剂FSA-55的制备技术。硫化剂FSA-55中硫质量分数为52%~56%,起始分解温度为120~150℃,闪点高达110~125℃,具有良好的安全性能及使用性能。通过与二甲基二硫醚(DMDS)、叔壬基多硫化物(TNPS)、二甲基硫化物(DMS)等传统硫化剂的性质进行对比,硫化剂FSA-55安全性能(闪点)及使用性能(硫含量、分解温度)均有较大提升,基本接近于进口硫化剂二叔丁基多硫化物(SZ54)的指标水平。通过与硫化剂DMDS的应用对比评价可知,该硫化剂具有良好的硫化性能,可完全替代硫化剂DMDS,具有良好的应用前景。  相似文献   
55.
The ageing behaviour of trimethylolpropane trioleate was investigated at different temperatures in a modified rotary bomb test apparatus. Some physicochemical properties of ageing oil samples, such as acid value, kinematic viscosity, and iodine value, were measured. The oil samples were analysed using gas chromatography, gas chromatography‐mass spectrometry, and gel permeation chromatography to assess the influence of temperature on the ageing behaviour of ester‐based oils. The results revealed that an increase in temperature could greatly speed up the ageing reaction and increase the formation of decomposition products. However, the degree of oil ageing remained similar when the same quantity of oxygen was consumed.  相似文献   
56.
介绍了几类催化环境友好过程,其中包括:固体酸,碱催化,以水为溶剂的均相催化及不对称催化。另外还对一些环保方面的现有催化过程的改进和新催化工艺的开发作了评述。  相似文献   
57.
几种纳米添加剂在环境友好润滑剂中的摩擦化学特性   总被引:3,自引:1,他引:2  
采用机械化学修饰法研制了三种纳米润滑添加剂,二硫化钼(MoS2)、聚四氟乙烯(PTFE)和氟化石墨(CxFy),考察了这些纳米级润滑剂在环境友好润滑剂中的摩擦化学特性。结果发现:这些纳米添加剂在环境友好润滑剂中具有较好的抗磨性能和良好的减摩性能;减摩性能优于常用的极压抗磨剂,其机理是在摩擦副表面形成迁移膜,起“滚动微轴承”的作用。  相似文献   
58.
Soybean oil was epoxidized using peracetic acid prepared in situ from acetic acid and hydrogen peroxide with Dowex 50 W‐8X as a catalyst. The epoxidized soybean oil was allowed to react with methylamine. The resulting adduct was identified and emulsified. The emulsified methylamine adduct was added at different concentrations to an emulsion (styrene/acrylic)‐based paint (blank). The effect of the methylamine adduct concentration on the physical, chemical, and mechanical properties of the paint was studied. Various tests such as metal substrate weight loss, corrosion, blister, and scratch resistance were performed to evaluate the efficiency of the prepared adduct. It was found that there is an optimum concentration at which the methylamine adduct is very effective as a corrosion inhibitor. This concentration is about 0.5% by weight. In comparison with chromate anticorrosive pigment, it was found that the methylamine adduct is superior with more economical and environmental advantages. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 286–296, 2001  相似文献   
59.
Chen.  NY 《石油与天然气化工》2000,29(2):61-63,67
尽管目前对汽油组分影响各种环境条件的理解还有限,但已经认识到,现有燃料中的几种组分若以高浓度释放到大气中,对环境是有害的,如溢漏、挥发损耗或不完全燃烧。这些组分包括芳烃特别是苯、高蒸汽压烃如n-丁烷、反应性烃如烯烃以及硫化合物,它们会促使烟和酸的形成,本文将阐述与当前炼油加工过程有关的这些环境问题  相似文献   
60.
这部分将简要介绍环境友好燃料炼厂的技术要求,并将这种“清洁”炼厂与传统技术基础上的新炼厂作经济分析比较。这种“清洁”炼厂借助附加的加工步骤消除了当前炼厂中生产的焦炭,这种产品的硫和重金属含量高。将原油的残油经流化床焦化和焦炭气化进行组合加工以生产H2,并将硫和金属作为有价值的副产品回收。此外,用清洁加工技术尽可能减少其它固体废物和空气/水毒物,该技术主要是用轻烯烃生产环境友好的高级运输燃料。尽管“  相似文献   
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