工业泵选用程序和方法

介绍了工业泵选用程序 ,一般应包括 :编制询价文件 ,审查并评比供货商的报价文件 ,发放定单 ,编制最终定货文件等步骤。给出了各步骤的主要内容及注意事项。     

Stable suspensions of ferroelectric nm-LiNbO3 — and nm-PbTiO3 — particles in hydrocarbon carrier liquids

Stable suspensions of nm-size LiNbO₃ - and PbTiO₃ -particles in hydrocarbon carrier liquids were produced by long milling processes. The suspensions show a big field-induced birefringence comparable to that of nm-BaTiO₃ -suspensions. The Kerr-effect data together with the in situ particle size determination using dynamic light scattering indicate that the particles are ferroelectric and single domain or superparaelectric. Ferroelectric particles with an average radius of about 10 to 15 nm would carry a mean permanent dipole moment of about 2000 Debye.     

我国水泥行业环保装备产业现状与发展趋势

我国水泥行业环保装备产业的技术水平和生产能力均已达到国际先进水平。我国加入世贸组织,水泥工业结构调整,水泥环保新标准等给我国水泥行业环保装备产业带来前所未有的市场空间。电收尘器的技术含量和系统控制水平将有较大的提升;袋除尘器将向着大型化和适应高温、高浓度方向发展。     

谈在低碳经济下我国玻璃工业的发展及对策

玻璃行业是社会各界关注的重点耗能行业之一,低碳经济条件下持续快速发展受到广大玻璃行业的关注.针对绿色经济为玻璃工业发展提供了巨大的市场空间,阐述了我国玻璃工业的发展和现状;介绍了新时期玻璃工业发展面临的机遇和挑战,研究了新形势下行业发展值得关注的问题,提出了玻璃工业的发展方向和对策.     

我国轮胎产业的状况与展望

着重叙述了我国轮胎产业规模与结构,十大名牌企业代表我国轮胎业最好水平,国内企业形式是国有、国有控股、民营、台资、外资各种形式并存.提出我国企业应形成合理的经济规模,才能实现更大的效益增长.我国轮胎产量逐年提高,子午化率也提高较快.轮胎品质还有待提高,应增强自主开发能力.轮胎的进口价格远高于我国轮胎出口价格,指出只有不断创新,才能使我国成为轮胎出口强国.只要轮胎企业抓住机遇,未来的中国轮胎业将会有更广淘的发展空间.     

我国硫酸工业入世十年嬗变

入世10年来,我国硫酸产量大幅增加,10年间年均复合增长率112．8％。硫酸原料结构布局已经发生了巨大变化,硫磺制酸所占比例大幅提高。同时,我国硫酸工业在大型化、自动化、设备材料技术、低温热回收、循环经济等方面都取得了长足的进步。今后的10年,我国硫酸工业更要坚持不懈地发展无碳能源经济、发展以硫酸为中心的循环经济、发展以创新为主导的知识经济,使我国成为可持续发展的硫酸强国。     

2014年国内合成橡胶产业回顾及展望

回顾了2014年我国合成橡胶新建装置的能力,主要合成橡胶产品的产量、进出口量、表观消费量以及丁二烯的供应状况,并对2015年国内合成橡胶产业的发展趋势进行了展望。     

煤化工产业科技发展综述

回顾了新型煤化工技术路线,指出煤制甲醇及下游产品、煤制油、以及以煤气化为龙头的合成氨是我国洁净煤利用技术的主要发展方向。     

Removal of 3—(3,4—dichlorophenyl)—1, 1 dimethylurea from aqueous solution by natural and activated bentonite

The adsorption of 3-(3,4-dichlorophenyl)-1,1 dimethylurea (diuron) on bentonite desiccated at 110°C untreated, and acid treated with H₂SO₄ solutions over a concentration range between 0.25 M and 5.00 M, from aqueous solution at 30°C has been studied. In addition, adsorption of diuron on combined acid/heat treated samples (0.50 M and 2.50 M H₂SO₄/200°C and 400°C) has also been studied. The experimental data points have been fitted to the Freundlich equation in order to calculate the adsorption capacities (K) of the samples; K values range from 0.92 μg g^?1 for the untreated bentonite up to 974.42 μg g^?1 for the 0.50 M H₂SO₄/400°C acid/heat treated bentonite. The removal efficiency (R) has also been calculated; R values ranging from 2.02% for the untreated bentonite up to 97.17% for the 0.50 M H₂SO₄/400°C acid/heat treated bentonite. The adsorption experiments show that bentonite heat treatment is more effective than bentonite acid treatment in relation to adsorption of diuron.     

Phase separation temperatures in the polystyrene—poly(α-methyl styrene)—methylcyclohexane system

The phase separation temperatures (PST) in the ternary system polystyrene (PS) (M_w = 1.75 × 10⁴ g mol⁻¹ — poly(α-methyl styrene) (PαMS) (M_w = 6.0 × 10⁴) — methylcyclohexane (MCH) and the binary systems PS-MCH and PαMS-MCH have been determined by using a He---Ne laser light-scattering apparatus over the total polymer weight fraction (W_{PS + PαMS}) range of 0.018 to 0.80 and various polymer blend ratios. The PST determined at a scattering angle of 0° agreed with those at 90° for the binary systems over polymer concentrations of 0.1 to 0.7 and for the ternary over W_{PS + PαMS} of higher than 0.3. Deviations of the PST determined at an angle of 90° from those at 0° were observed in the ternary system when W_{PS + PαMS} was lower than 0.3. Two phase separation temperatures, at which the intensity scattered from zero angle changed discontinuously, are observed at concentrations lower than W_{PS + PαMS} = 0.042 in the ternary system. The PST in the ternary system decreases monotonically with increasing W_{PS + PαMS} over 0.3 to 0.7. The phase diagram for the PS-PαMS-MCH system at W_{PS + PαMS} = 0.8 is characterized by a maximum PST around − 14°C.     

Hydrogenation of 3-hydroxypropanal in trickle beds — experimental and modelling

Hydrogenation of 10% aqueous solution of 3-hydroxypropanal (HPA) was adiabatically carried out over cylindrical Ni/SiO₂/Al₂O₃-catalyst pellets (?? 0.8 + 5 mm) in a trickle bed (?? 76 × 5200 mm) at 2.6 to 8.0 MPa. The concentration and temperature profiles in the trickle-bed were measured at different flow rates of liquid. A mathematical model was developed under consideration of heat transfer, interphase mass transfer, intraparticle diffusion and deactivation of catalyst pellets at partial wetting with different wetting geometries. The model fits the measured data satisfactorily when its kinetics of deactivation is modified by a factor determined by regression of data measured in the trickle bed.     

Interactions NO—CO and O2—NO—CO on CuCo2O4/γ-Al2O3 and on γ-Al2O3- and CuCo2O4/γ-Al2O3-supported Pt, Rh and Pt—Rh catalysts, a transient response study

The interactions NO—CO and O₂—NO—CO have been studied onCuCo₂O₄γ-Al₂O₃ and on γ-Al₂O₃- and CuCo₂O₄γ-Al₂O₃-supported Pt, Rh and Pt—Rh catalysts. The deposition of noble metals (Pt, Rh and Pt—Rh) on CuCo₂O₄γ-Al₂O₃ instead of γ-Al₂O₃ is beneficial in: lowering the temperature at which maximum N₂O is formed and decreasing the maximum N₂O concentration attained; lowering the onset temperature of NO to N₂ reduction, and increasing the N₂ selectivity; preserving the activity towards NO to N₂ reduction on a higher level following the concentration step NO + COO₂+ NO + CO and changing the conditions from stoichiometric to oxidizing (50% excess of oxidants). The reason for this behaviour of the CuCo₂O₄γ-Al₂O₃-based noble metal catalysts is the formation (reversible) of a reduced surface layer on the CuCo₂O₄ supported spinel under the conditions of a stoichiometric NO + CO mixture.     

Physical characterization and pressure—temperature microscopy of the pyrite—pyrrhotite transformation

Structural changes occurring during the hydrogen-assisted pyrite-pyrrhotite transition are characterized over the temperature range 400–600 °C. Newly developed pressure-temperature microscopy gave in-situ observations of pyrite decomposition at elevated temperatures and gas pressures. Composition of pyrrhotites was measured by X-ray diffraction and correlated with krypton surface areas. Surface areas increased with an increase in pyrite reduction due to a decrease in molar volume accompanied by the development of porosity. Increases in specific surface area are inversely proportional to the reduction temperature. Heats of adsorption of krypton on pyrite increase linearly with increases in the relative amount of the (100) crystallographic faces.     

化工塔板的综合评价与选择

本文用多目标决策对比系数法,对化工塔板总体性能排序进行了综合分析和评价,为塔板的设计与选择提供依据。     

Poly(4-methylstyrene-co-chloromethylstyrene): A negative electron beam resist—synthesis and lithography evaluation

Synthesis and lithographic characterization of a series of negative acting electron sensitive resists based on poly(4-methylstyrene-co-chloromethylstyrene) are reported. The sensitivity and contrast of these resists were found to depend on the chloromethylstyrene (CMS) content and an optimum value of 5 wt% was determined from consideration of parameters associated with the reproducibility of the synthetic method and also the lithographic performance. Both the sensitivity and resolution were found to depend on the molecular weight and CMS content of the copolymer. Several methods of scale up for the synthesis were explored, the route having a very significant influence on the film formation characteristics of the resists. The reactivity ratios of the monomers were measured in order that the compositional drift, which occurs during the synthesis, could be quantified. The effect of solvent composition and molecular weight of the copolymer were explored in relation to the quality of the resulting lithography. These studies have indicated that the copolymer has the potential of being used as a VLSI sub-micron resist with good plasma etch resistance.     

MoO3—Fe2O3 catalysts: Characterization and activity for isopropyl alcohol decomposition

The vapour-phase dehydration and dehydrogenation of isopropyl alcohol (IPA) have been carried out over pure MoO₃ and Fe₂O₃, produced by calcination of ammonium heptamolybdate and of iron (III) nitrate respectively, as well as MoO₃ mixed with 0·5 and 50 mol% Fe₂O₃, prepared from the same materials. All catalysts were calcined in air, in the temperature range 200–600°C for 5 h, and were characterized by thermal analysis (TG, DTA), XRD, IR and S_BET. Surface areas decreased with increasing calcination temperature, and the catalytic activity of the pure oxides MoO₃ and Fe₂O₃, as well as of MoO₃–0.5 mol % Fe₂O₃, increased with their S_BET. The activity of MoO₃–50 mol % Fe₂O₃, which was independent of its S_BET, could be attributed to the increased intensity of terminal Mo—O bonds as shown by IR spectra. The activation energies for the decomposition of IPA over catalysts calcined at 250 and 500°C are tabulated.