液体洗涤剂生产中微生物的控制及防腐剂的评价方法

通过对液体洗涤剂生产的长期监控,发现水系统的控制和软化水的贮存对产品微生物的控制至关重要。用微生物挑战性实验评价液体洗涤剂的防腐性能是一种较好的方法,pH值对防腐性能也有比较大的影响,因此在评价中应同时考虑产品的pH值,明确产品的pH值控制范围。     

关于泊车过程中采集信息误差分析及解决方法

为了更好的提高自动泊车系统中图像采集系统的精度,必须要考虑影响图像采集的主要因素,如:视场灰暗、温度、振动、镜头畸变、视线馈线、雨天、雾天等因素对采集系统精度的影响,并给出了一种有效的减小或消除误差的方法,以提高图像采集系统的精度,直接提高图像采集系统的精度、泊车精度。     

异氰酸根含量和环氧值的同时测定方法研究

分别采用甲苯-二正丁胺法和盐酸-丙酮法测定样品中NCO含量和环氧值,研究了样品中NCO基团和环氧基团对彼此测定的影响。结果显示：环氧基团的存在对NCO基团含量的测定没有影响,而NCO基团对环氧值的测定有影响;在50℃左右温度下,利用甲醇使NCO基团封闭可消除NCO基团对环氧值测定的影响,建立了一套同时定量分析样品中NCO基含量和环氧值的方法。     

GB 151中浮头式换热器管板设计方法的理论依据及其应用

阐述了国家标准GB 151中浮头式换热器设计方法的理论依据。在此基础上,进一步给出了如何应用GB 151中浮头式换热器对应于最小管板设计厚度的公式与曲线,计算实际管板厚度下的管板应力和换热管应力的方法。通过一个实际算例,说明当管板的实际厚度与其最小设计厚度相差较多时,换热管中的应力可以大大降低。     

分离模拟计算中简捷法与严格法的联合应用

本文对多组分多级分离的计算机模拟计算中联合使用简捷法与严格法即用简捷法计算结果作为严格法的初值进行了研究,并结合具体问题进行了实例计算。结果表明：简捷法是严格法确定初值的一种非常有效的方法。     

聚合反应体系中二氧化硫含量的影响因素及控制方法

丙烯腈、醋酸乙烯的共聚物含有二氧化硫(SO)2,它是以磺酸基团的形式存在,以SO2的形式进行定量计量,其组分的稳定性直接影响聚合物的染色指标。通过实际生产经验并结合理论知识,对聚合反应体系中SO2含量的影响因素及控制方法进行了剖析和探讨,通过分析影响SO2变化的因素,采取一系列针对性的措施,使聚合反应能够在较短的时间内生产出品质稳定的聚合物。     

顺丁橡胶成品胶门尼升值的原因及控制方法

本文主要分析了顺丁橡胶生产过程中成品胶门尼升值的原因并提出了相应的控制方法。     

Tocopherol distribution and oxidative stability of oils prepared from the hypocotyl of soybeans roasted in a microwave oven

Whole soybeans (Glycin max L.) were roasted by exposure to microwaves at a frequency of 2,450 MHz, and their hypocotyls were separated from other tissues (seed coat and cotyledons). The quality characteristics and composition in the hypocotyl oils were studied in relation to their tocopherol distributions and were evaluated as compared to an unroasted oil sample. Only minor increases (P<0.05) in chemical and physical changes of the oils, such as carbonyl value, anisidine value and color development, occurred with increased roasting time. Significant decreases (P<0.05) were observed in the amounts of phospholipids in the oils after microwave roasting. Nevertheless, compared to the original level, more than 80% tocopherols still remained after 20 min of roasting. These results suggest that the exposure of soybeans to microwaves for 6 to 8 min caused no significant loss or changes in the content of tocopherols and polyunsaturated fatty acids in the hypocotyls. Therefore, a domestic microwave oven would be useful as a simple and quick means for preparing hypocotyl oil of good quality.     

中国南方城市污水厂污泥特性研究及处置对策

采用统计概率分布方法,对中国南方地区中小型污水处理厂的污泥特性、产生原因、处理处置现状进行深入分析,并结合欧盟污泥处理处置现状和未来发展趋势,对中国南方地区污泥处理处置技术的未来发展趋势进行预测,给出应对策略。     

Variation in stability of endogenous reference genes in fallopian tubes and endometrium from healthy and ectopic pregnant women

RT-qPCR is commonly employed in gene expression studies in ectopic pregnancy. Most use RN18S1, β-actin or GAPDH as internal controls without validation of their suitability as reference genes. A systematic study of the suitability of endogenous reference genes for gene expression studies in ectopic pregnancy is lacking. The aims of this study were therefore to evaluate the stability of 12 reference genes and suggest those that are stable for use as internal control genes in fallopian tubes and endometrium from ectopic pregnancy and healthy non-pregnant controls. Analysis of the results showed that the genes consistently ranked in the top six by geNorm and NormFinder algorithms, were UBC, GAPDH, CYC1 and EIF4A2 (fallopian tubes) and UBC and ATP5B (endometrium). mRNA expression of NAPE-PLD as a test gene of interest varied between the groups depending on which of the 12 reference genes was used as internal controls. This study demonstrates that arbitrary selection of reference genes for normalisation in RT-qPCR studies in ectopic pregnancy without validation, risk producing inaccurate data and should therefore be discouraged.     

293.15 K到333.15 K温度下一些氨基酸及其相应基团水溶液中的偏摩尔体积研究

Densities of aqueous solutions of eight amino acids, glycine, L-alanine, L-valine, L-isoleucine, L-serine,L-threonine, L-arginine and L-phenylalanine, are measured as a function of amino acid concentration from 293.15 K to 333.15K. These data are used to calculate the apparent molar volume V and infinite dilution apparent molar volume V0 (partial molar volume). Data of five amino acids are used to correlate partial molar volume V0 using group contribution method to estimate the contributions of the zwitterionic end groups (NH3 ,COO-) and CH2group, OH group, CNHNHNH2 group and C6H5(phenyl) group of amino acids. The results show that V0 values for all kinds of groups of amino acids studied increase with increase of temperature except those for CH2 group,which are almost constant within the studied temperature range. Data of other amino acids, L-valine, L-isoleucine and L-threonine, are chosen for comparison with the predicted partial molar volume V0 using the group additivity parameters obtained. The results confirm that this group additivity method has excellent predictive utility.