丙烯酸乙酯反应液组成分析方法的改进

针对丙烯酸乙酯反应液组成分析中存在的基线漂移、分析时间长的问题，根据色谱理论，在试验的基础上，选择合适的分析条件，以毛细管柱色谱柱分析取代原填充柱分析，改进后的分析方法合理、分析结果准确可靠，并大大缩短了分析时间。     

论控制分析与成品分析的区别

控制分析与成品分析有许多不同的要求,合理安排分析的标准,可及时准确地反映样品的分析数据,或者说合理化分析的时间,既减少了分析时间又降低了分析成本。     

微课在仪器分析实验教学中应用与探讨

仪器分析实验是仪器分析课程教学中较为重要的组成部分。文章针对我校仪器分析实验授课过程中存在的几点问题进行分析,并将微课教学引入仪器分析实验教学,对微课在仪器分析实验教学中起到的作用和运行情况进行分析,探讨微课模式在仪器分析实验教学中的应用前景。     

现代有机分析新方法新技术在医药分析及食品分析中的应用

介绍了现代有机分析的产生发展及应用,综述了:新型纳米材料在有机分析中的应用;现代有机分析在医药学检测中的应用;现代有机分析新方法新技术在食品分析中的应用。并对有机分析的发展进行了展望。     

基于仪器分析技术在油品分析研究

从油品分析概述入手,分析了油品光谱法分析的重要性,之后注重探讨了基于仪器分析技术的油品分析,主要包括气相色谱法、高效液相色谱法、质谱法、近红外等,进一步促进仪器分析技术在油品分析中的应用和发展。     

浅谈水质分析

文章介绍了水质分析的定义,水质分析的意义,水质分析的质量控制以及水质分析的发展前景。重点介绍了水质分析质量控制的因素以及措施。     

检测实验室在科技进步与科技创新中的定位

通过调查研究,提出炼油企业检测实验室定位方向:吸收引进先进的分析检测技术,逐步完善现有的分析检测方法标准,改革创新方法标准满足现实生产、产品质量需要,发展在线分析技术提高整体分析效率。改革实验室的科技进步与科技创新理念:以解决企业生产难点、重点、瓶颈为工作重心,以完善现有分析技术为主,以持续提高分析准确率、分析效率、分析速率为目标,寻求新的技术突破、新的理论支持。     

真密度方法的建立及应用

由于质检中心分析抽出油进厂验收密度的方法一直是采用稀释法密度分析,此方法从样品稀释到分析再到换算结果报出分析过程时间较长,分析过程中影响因素较多,中心现有一台真密度仪,用来分析焦炭的密度,经过论证,通过具体研究实验条件,从对仪器的校准、抽出油样品在不同温度下的比对分析及用稀释法密度分析、比重瓶法密度分析,得出结论:抽出油密度可以采用真密度仪进行分析,样品的准确性及重复性均符合标准要求,分析时所需样品用量少,样品室清洗方便,也可减少对环境的污染,可进行抽出油进厂验收密度的日常分析。     

PSA提氢装置程控阀运行故障分析及处理

程控阀的运行效率严重影响PSA装的提氢效率,严格控制程控阀的运行效果,分析其存在的问题,并且根据理论分析,本文首先分析了PSA工艺流程,其次分析了程控阀的异常现象分析与处理,最后分析了程控阀运行优化,供相关人员参考。     

谈谈建立财务分析系统的构想

财务分析是指财务分析者以企业有关会计资料为依据,采用专门的方法,对企业生产经营成果和财务状况进行分析研究的一项管理活动或行为.财务分析主体是指与企业有现存的和潜在的利益关系,并希望通过对企业财务分析而获得企业财务信息的单位或个人.一般来说企业财务分析的主体有企业经营者,企业投资者,企业债权人以及其他与企业经济利益有关系的单位或个人.由于企业财务分析主体的多元性,决定了企业财务分析目标的多元性.     

Confocal microscope—A valuable tool for examining wood-coating interface

The suitability of confocal laser scanning microscopy (CLSM) in examining a wood-coating interface was evaluated using a clear coating system. A comparison of the images of the wood-clear coating interface obtained using CLSM and light microscopy (LM) showed a marked superiority of CLSM in revealing the details of the physical nature of the interaction between the clear coating and the wood cell walls in the surface layer. The most distinct advantage of CLSM was in its ability to clearly resolve penetration of the coating into very fine cracks in cell walls, details not obtainable with LM. The information presented here demonstrates that CLSM has the potential to greatly enhance our understanding of the physical aspects of an interaction between the wood and coating at the interface.     

Measured kinetics of the acid-catalysed hydrolysis of sugar cane bagasse to produce xylose

Experimental trials of the water hydrolysis of bagasse to produce xylose, arabinose and glucose were conducted using a temperature-controlled microwave digester. The experimental variables were temperature, ratio of water mass to bagasse mass, type of bagasse material and reaction time. The pH of the liquid and concentration of dissolved xylose, arabinose and glucose were measured at the completion of each trial. Kinetic modelling of the global rates of formation of monosaccharide products was performed using schemes based on earlier researchers’ models of acid hydrolysis using mineral acids. For the most plentiful product, xylose, the most accurate kinetic model of the global reactions was determined to be two parallel pathways for hydrolysis of xylan to xylose followed by a single pathway for xylose decomposition. The calculated activation energies of the reactions were within the range reported by other researchers for the hydrolysis of a range of lignocellulosic materials using mineral acids.     

机制砂岩性与级配对混凝土抗硫酸盐侵蚀性能的影响

为了探究不同岩性、不同级配机制砂对混凝土性能的影响,对三种不同岩性机制砂混凝土及天然河砂混凝土的工作性和抗压强度进行研究。此外,对比分析了四种混凝土在干湿循环制度下的抗硫酸盐侵蚀性能。结果表明,天然河砂混凝土的工作性优于机制砂混凝土,钙质机制砂混凝土的工作性略好于硅质机制砂混凝土。机制砂混凝土的抗压强度优于天然河砂混凝土,在硫酸盐侵蚀循环作用下的力学性能变化趋势与天然河砂混凝土基本一致。在相同级配条件下,机制砂混凝土的抗蚀系数高于天然河砂混凝土;机制砂岩性并不会对混凝土抗硫酸盐侵蚀性能带来负面影响。级配良好的机制砂可以增强混凝土抗压强度和抗硫酸盐侵蚀性能。     

聚氨酯涂覆胶辊的研制

本文论述了彩色金属薄板生产用聚氨酯涂覆胶辊材料的合成原料选择、配方设计和工艺路线、以及力学性能和溶胀性能等．从测试数据看出．与美国进口样品相比．其力学性能和溶胀性能普遍优于后者。     

沥青质引发的蜡油体系结蜡层分层现象及分层规律

利用自主研发的Couette结蜡装置,对蜡含量相同的油样1(不含沥青质)和油样2[含0.75%(质量分数)沥青质]进行结蜡实验,并研究其结蜡层的分层现象和分层规律。通过对油样1和油样2结蜡表层和底层的宏观形貌、DSC放热、析蜡量、蜡晶微观形貌的分析发现:油样1结蜡层无明显分层现象,而油样2结蜡层分层现象明显,沥青质的加入导致了结蜡层的分层。与结蜡表层相比,油样2结蜡底层的析蜡点、蜡含量与沥青质含量显著升高,蜡晶形貌发展为致密的类球状大蜡晶。油样2结蜡表层沉积量随壁温的升高、油壁温差和转速的增大而减小;结蜡底层沉积量随壁温升高而减小,随油壁温差和转速的增大而增大;总的蜡沉积量随壁温的升高和转速的增大而减小,随油壁温差的增大先增大后减小。     

Functional properties of proteins in foods

The measurement of functionality of protein food ingredients has developed somewhat haphazardly, probably due to the wide range of proteins used as ingredients and the diversity of foods. Studies of the physiochemical properties of proteins should enable prediction of a proteins response to process environments and prove more fruitful than many of the empirical measurements of functionality. The effects of pH, salt type and concentration on the phase behaviour of the oilseed globulin and arachin, demonstrates the complexity of protein solubility and the inadequacies of simple tests that have arisen. Studies of the effects of salts and conditioning on meat fibres, coupled with measurement of the location of water in pellets from water holding tests enable the latter to be applied with increased confidence. Comparison of the endothermic transitions observed on heating with the development of storage and loss moduli allow the contributions of domains of skeletal muscle myosin to gel structure to be investigated.     

Factors affecting levels of some phenolic compounds,digestibility, and nitrogen content of the mature leaves ofBarteria fistulosa (Passifloraceae)

Levels of total phenolics, condensed tannins, acid detergent fiber, pepsin/cellulase digestibility, and nitrogen in mature leaves of 26 individuals of the ant-plant,Barteria fistulosa, have been determined. Analysis of the results in terms of the presence or absence of ants and the position of the branch from which the leaves were collected showed no relationship with concentrations of phenolics or fiber and only a weak relationship with digestibility and nitrogen. By contrast, light intensity strongly influenced levels of phenolics, notably condensed tannins, so that mature leaves of individuals growing in direct sunlight were less digestible and appeared to be of lower quality as food for herbivores than did mature leaves of individuals in shaded positions. Possible reasons for the variation in condensed tannin levels are discussed.     

Effect of some floral scents on host finding by thrips (Insecta: Thysanoptera)

The role of floral scents in host location by flower-dwelling thrips is investigated by experiment in the field. The scent of anisaldehyde significantly increased the catches of seven species of flower-dwelling thripid, but had no significant effect on three species of cereal thripid and one species of flower-dwelling aeolothripid. The catches of white (without UV) traps were increased by a factor of 3.3 to 8.3 in the presence of the scent.     

The Viscosity of cottonseed oil,fractionation solvents and their solutions

Cold fractionation of cottonseed oil is made difficult by the high viscosity of the oil. This study was aimed at demonstrating the effect of solvents on the viscosity of mixtures between 0°C and 25°C with a view to facilitating the fractionation of refined cottonseed oil. The solvents used were acetone, methylethylketone, methylisobutylketone, hexane and heptane. Measurements of viscosity were carried out by means of a capillary viscometer. The ratio of the viscosity of cottonseed oil to that of pure solvents is of the order of 300. The viscosities of solutions of various ratios of solvent to oil (1/3, 1/1, 3/1) are between those of cottonseed oil and the pure solvents. The effect of the solvent/oil ratio overrides that of solvent nature. The effect of solvent in reducing the viscosity of cottonseed oil is by descending order: acetone, hexane, methylethylketone, heptane, methylisobutylketone.