Response of Bacillus cereus spores to high hydrostatic pressure and moderate heat

The effects of high pressure (400-600 MPa) and moderate heat (60-80 °C) treatments at various process times (10-20 min) on the reduction of Bacillus cereus As 1.1846 spores, suspended in milk buffer were investigated. In the present work, response surface methodology (RSM) was employed, and a quadratic equation of high hydrostatic pressure inactivation was built with RSM. By analyzing response surface plots and corresponding contour plots and by solving the quadratic equation, experimental values were shown to be significantly in agreement with predicted values, since the adjusted determination coefficient was 0.9752 and the level of significance was P < 0.0001. Optimum process parameters for a six-log cycle reduction of B. cereus spores were obtained: pressure, 540.0 MPa; temperature, 71 °C; and pressure-holding time, 16.8 min. The adequacy of the model equation in predicting optimum response values was verified effectively using experimental test data that was not used in the development of the model.     

高品质海绵钛产业化技术在生产中的应用

从提高原材料纯度、优化还原一蒸馏设备及操作工艺等方面,提出了镁法海绵钛生产的技术改进措施,实现了高品质海绵钛的产业化生产,对提高海绵钛生产企业的核心竞争力,促进我国钛工业的健康、可持续发展具有重要的意义。     

Effect of boron source on the catalyst reducibility and Fischer–Tropsch synthesis activity of Co/TiO2 catalysts

A series of Co/B/TiO₂ (B=ammoniumborate, boric acid, o-carborane, 0.01–1.5 wt.% B) catalysts were synthesized. The addition of boron decreased the reducibility of the Co as determined from temperature-programmed reduction studies and H₂ reduction/O₂back titration studies. This in turn decreased the FT activity but not the turnover frequency of the Co catalyst.     

受冲击构件的分析

本文分析了被冲击物体的质量、冲击点或支承处材料局部塑性变形而损耗的能量及初等公式的误差等对冲击的影响。提出能量损耗折减计算,并列出系统能量转换式求得冲击系数K′_d=(1+((1+2H/η△j)η)~1/2     

Water Quality Improvements with the Use of Ozone at the Los Angeles Water Treatment Plant

At 600 mgd (2,270 ML/day), the recently completed Los Angeles Aqueduct Filtration Plant (LAAFP) is one of the world's largest water' treatment facilities utilizing ozone for pretreatment. The treatment process features direct filtration at rates of up to 13.5 gpm/ft² (33 m/h). Under the optimized full-scale operation, preozonation has resulted in significantly reduced THM levels and very low effluent turbidity with low operating costs.     

电弧炉用钢铁炉料的发展动态

随着电炉钢生产的增长及优质废钢供应短缺和价格增长，电炉钢生产者必须使用大量劣质废钢，同时要使钢中残余有害元素符合要求，从而发展了用直接还原铁混合，稀释循环旧废钢生产优质钢材的工艺，并促使世界直接还原铁生产迅速增长。     

COREX法采用的高氧化镁渣性能及作用探讨

通过对COREX法高MgO渣性能、特点的探讨，认为在COREX熔炼条件下，高MgO渣既具良好操作性能，又能满足高硫负荷下的脱硫，还有利于低硅生铁的生产和提高预还原效率。     

丁醇还原法制备Fe_3O_4的研究

研究了丁醇还原法制备Fe_3O_4的设备和工艺条件,分析了丁醇还原机理,考察了脱水、还原温度对Fe_3O_4微观结构的影响。实验表明,330℃脱水和还原时,所得Fe_3O_4的比表面积最大,矫顽力最高,活性最强。     

The effect of sulphur present in coal on the course of its reduction in the potassium/liquid ammonia system

Two low-rank coals of high content of sulphur and low sulphur content orthocoking coal were chosen as the subject of study. The process of reduction was carried out twice, for raw and demineralised, by the Radmacher method, coals. Elemental and spectral analyses of the initial coals and the products obtained from them were made. The solubility of the coals in dichloromethane and the average molecular weight of the extracts were determined. The degree of conversion of the coals studied to the products soluble in dichloromethane was found to be surprisingly high regarding the low-rank coals. A hypothesis is put forward that the high content of sulphur in low-rank coals can endow them with certain properties typical of coking coals.