道化学法在偏二甲肼储库安全评价中的应用

运用道化学法对某偏二甲肼(UDMH)储库进行安全评价,得出了有无安全措施补偿的火灾爆炸指数、危险等级、暴露半径、暴露面积和暴露体积等。评价结果表明,补偿前伤害半径为59.4 m(对特定储库),补偿后伤害半径为35.05 m,说明采用安全措施补偿是很有必要的,为事故的风险预防和对UDMH储库的管理提供了依据。但是UDMH储库还需要进一步进行安全措施补偿的完善,使伤害等级进一步下降。     

赖特与构成--建筑及装饰设计的"有机线条概念"

赖特的建筑作品中体现出来的设计原则与当时通常的原则相去甚远,他的建筑思想完全游离与19世纪浪漫主义风格中著名的"日本风格"以外.他的设计思想主要来源于厄内斯特·范诺罗莎(ErnestFenollosa)对日本艺术独特的诠释.事实证明,当范诺罗莎关于日本艺术的分析被阿瑟·道(Arthur Dow)转移到常规艺术教育系统中以后,这种对日本艺术全新的见解直接影响到了赖特的早期作品.范诺罗莎--道关于"合成线形思维"的艺术理论支持赖特以相似的方法完善自己的建筑原则.     

丙烯腈装置火灾爆炸危险分析控制

运用美国道化学公司火灾、爆炸危险指数评价法(第七版)对某石油化工厂丙烯腈装置各单元的火灾爆炸危险性进行分析、分级,并就影响因素进行探讨,提出一些控制措施。     

Electroactive Thermoplastics

Proton‐exchange membrane fuel cells are one of the most commercially important applications of electroactive polymers. It has been found that their performance can be optimized by controlling water transport via thin layers of ionomers with increasing equivalent weights in the catalyst layer (see Figure). Recent developments in this area are presented here within the context of development of innovative electroactive materials.     

Catalytic Hydrogenation of Polystyrene

The use of ultra wide pore silica as a catalyst for the hydrogenation of polystyrene to give poly(cyclohexylethylene) (PCHE) has facilitated the development of a dramatically improved process with much milder conditions. The large pores allow rapid diffusion into and out of the catalyst, so that the interior surfaces are also available for reaction. The mild conditions give rise to high‐quality PCHE, whose structure is shown in the Figure.     

Modeling Foam Growth in Thermoplastics

Foaming of thermoplastic polymers is a complex process. Here models are presented that address the viscoelastic character of the thermoplastic melt during the expansion phase of foam development. Each cell is described as consisting of a spherical gas bubble surrounded by a spherical shell of polymer containing dissolved gas (see Figure).     

Shear Yielding in Blown Oriented Polystyrene Films

Control over orientation is important for polystyrene (PS) films since it can affect brittleness in these materials. These authors discuss how the film morphology can be varied by orientation processing in amorphous bubble‐blown PS films and how it influences the properties and performance of the film. The Figure shows the film morphology resulting from straining along the transverse direction of the blown bubble.     

Properties and Applications of Microemulsions

Microemulsions are thermodynamically stable, fluid, optically clear dispersions of two immiscible liquids. Recent interest in microemulsion systems has resulted from their utility in a broad range of applications including enhanced oil recovery, consumer and pharmaceutical formulations, nanoparticle synthesis, and chemical reaction media. However, the high levels typically required to ensure complete microemulsification and formulation stability often result in unacceptably high residue, contaminant levels, and formulation cost. One way to reduce surfactant requirements in microemulsion systems is through the use of efficient surfactants and interfacially active cosurfactants. We have explored and developed microemulsion systems based on efficient anionic surfactants and glycol ether cosurfactants that are stable to temperature and compositional changes and yet employ low levels of non‐volatile surfactants. These microemulsion systems are finding utility in a range of applications, including consumer and industrial cleaning formulations, chemical reaction media, polymerization, and active ingredient delivery.     

Lightweight Cellular Plastics

Plastic foams have found a number of applications in the energy absorption, thermal, and acoustic markets. Here advances that have been made with extruded polystyrene, polyolefin, and polyurethane foams, and their uses, particularly in the automotive industry, are highlighted. The Figure shows a 65 % compressed foam.     

Application of a gamma-radiation density gauge for determining hydrodynamic properties of fluidized beds

A modified, off-the-shelf, gamma-radiation density gauge has been interfaced into a microprocessor and mounted to a movable assembly mechanism which allows fluctuating bed density to be monitored on-line at any axial height in a fluidized bed. The signal processing required to determine expanded bed height L_f, dense phase voidage ε_D, dense phase superficial gas velocity u_Do, cross-sectional centerline bubble phase volume fraction 〈δ_B〉^t_c, bubble size d_b, frequency f_b, is described in detail. Example measurements are presented as made on both a cast-acrylic model column and an industrial, pilot-scale, high-pressure, fluidized-bed reactor. Accuracy of the measurements is discussed.