聚合物挤出加工中有关温度分布计算、测量、控制方法概述

本文介绍了聚合物挤出加工中关于温度分布的研究进展，对温度分布计算方法进行了分析对比，说明了各种方法的适用范围。同时对各种温度测量方法作了简要介绍，说明了测量方法特性，最后对温度控制方法进行了分析，介绍了各种方法的应用。系统分析后认为，采用数值模拟方法是温度分布计算的发展方向。     

浅析《化妆品补充检验方法研究起草技术指南》

为规范化妆品补充检验方法研制工作，2021年4月，国家药品监督管理局发布了《化妆品补充检验方法研究起草技术指南》。本文对《化妆品补充检验方法研究起草技术指南》的规定和要求进行了全面分析，对法律依据和研制范围、主要研制方向、方法文本编写要求和方法验证等内容进行了梳理，并结合《药品补充检验方法研制指南》，对立项申报和方法研制技术要求两项内容给予了重点解读，对化妆品补充检验方法研制工作提出了有针对性的建议，以期为药检机构的相关人员开展化妆品补充检验方法研制工作提供参考。     

聚氯乙烯化学交联研究进展

综述了应用化学方法制取交联聚氯乙烯的研究进展，对各种交联方法进行了深入探讨，并对交联聚氯乙烯的结构表征方法进行了介绍。     

3,4-二甲基苯胺合成进展

综述了3，4-二甲基苯胺合成的九种方法并对各种方法作了评述，对其中两种最适合于工业生产的方法作了详细比较。     

硫磺法制氢溴酸的合成研究

本文对氢溴酸的合成方法进行了介绍和比较，对硫磺法制氢溴酸的方法进行了研究，确定了较为合理的工艺条件，产品收率＞92％，得到了较为满意的结果。     

利用原子吸收光谱测定陶瓷原料中钙,镁方法的研究

本文试验了利用原子吸收分光光度法测定陶瓷原料中钙、镁含量的方法。在本试验中，对影响测定准确度的各种因素，干扰情况及消除方法进行了较详细的研究，并应用所建立的方法对样品进行了测定，取得了满意的结果。     

长距离流体输送管道泄漏检测与定位技术的现状与展望

介绍基于软件的泄漏检测和定位方法的发展现状，即基于模型的方法、基于信号处理的方法和基于知识的处理方法等，对上述方法存在的优缺点进行了评述，并对泄漏检测和定位方法的未来发展方向提出了作者的看法。     

陶瓷器皿高差缺陷的测量

本文对目前测量陶瓷器皿高差的方法进行了分析，提出了一种新的方法，并用应变悬臂梁位移传感器进行了实验测量，结果表明，提出的方法科学合理，实用可靠。     

哒螨灵中间体对叔丁基苄硫醇的研制开发

本文介绍了由对叔丁氯化苄，硫氢化钠合成对叔丁基苄硫醇的方法，比较了哒螨灵两种合成方法的优劣，并预测了农药中间体对叔丁基苄硫醇的市场前景。     

碳纳米管的纯化

介绍了碳纳米管的结构特征，对目前碳纳米管的纯化方法进行了评述，重点讨论了液相氧化法纯化碳纳米管的方法及特点，并对纯化机理作了解释。     

轻质油品脱臭催化剂的研究和应用

轻质油品中都有不同含量的硫醇存在,不仅使油品产生恶臭,腐蚀设备,而且使其质量和安定性下降。所以,在石油加工过程中,常需要脱除油品中的硫醇或将其转化为危害较小的二硫化物。介绍了轻质油品脱臭方法和新型脱臭工艺的工业应用。     

轻质油品脱臭催化剂的研究进展

轻质油品中都有不同含量的硫醇存在,不仅使油品产生恶臭,而且使油品的质量和安定性下降,硫醇还具有腐蚀性。所以石油加工过程中,常需要脱除油品中的硫醇或将其转化为危害较小的二硫化物。     

轻质油品脱硫醇技术进展

对炼油工业轻质油品脱硫醇 (脱臭 )技术的进展情况进行了综述。介绍了几种Merox工业化脱臭工艺技术 ,以及国内近几年研究开发的脱臭技术在工业上的应用情况 ,指出了油品脱硫醇技术的研究开发方向     

Evaluation of tests for rancidity in edible packaged oils

Summary Organoleptic tests, in spite of their limitations, were the most satisfactory methods of determining the quality of corn and cottonseed oils which had aged in sealed containers. The chemical and physical tests used in this investigation were influenced more by storage conditions, such as exposure to light or the presence of air, than by the actual organoleptic state of the oil. Changes in the methylene blue fading time of an oil were dependent on the presence of air or a high temperature during storage. Aldehydes, as determined by the bisulfite method, increased in oils exposed to air but their formation in oils in sealed containers was very slow even with extensive development of rancidity. No significant changes in the film pressure of oil in sealed containers took place except in samples exposed to light for several months, however, aeration of an oil at 100° C. resulted in a rapid change in film pressure. Exposure to light caused the color of the oils to fade, exposure to air caused darkening, yet both factors contributed to the development of rancidity. The induction period of the oils stored in sealed containers depended upon their original peroxide value which in turn was influenced by exposure to light. Exposure of sealed samples of oil to light caused a destruction of peroxides. The chlorophyll value of oils and the fluorescence changed rapidly when they were exposed to light; however, oil could be made rancid in the absence of light with little or no significant change in its chlorophyll value. Preliminary polarographic and light transmission studies in the ultraviolet and infrared regions of the spectrum failed to reveal any changes in the oils which could be correlated with the development of rancidity. Contribution No. 588, Massachusetts Agricultural Experiment Station.     

Fragrance‐Containing Microcapsules Based on Interfacial Thiol‐Ene Polymerization

In this study, microcapsules containing fragrance oils as active agent were synthesized by interfacial thiol‐ene polymerization in oil‐in‐water emulsion. One water‐soluble dithiol and four oil‐soluble acrylates were used as “click”able monomers. The polymerization kinetics was studied by HPLC and ¹H‐NMR. The size and morphology of the microcapsules were characterized by means of light scattering, optical microscope, and scanning electron microscope, and their thermal property was examined by TGA. The encapsulation efficiency and stability of the microcapsules were monitored at room temperature and 45 °C for 1 month. In general, this interfacial thiol‐ene polymerization was demonstrated to be a facile and efficient approach for fragrance microencapsulation with new and stable shell materials. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43905.     

Gewinnung leichter Kohlenwasserstoffe aus schweren Ölen — Verfahren und Entwicklungen

Manufacture of light hydrocarbons from heavy oils – processes and developments . High quality crude oils are running short and their price continues to increase. At the same time there is a trend towards light petroleum products for use as transportation fuels or petrochemical raw materials. Consequently, the conversion of heavy oils, i.e., particularly distillation residues but also heavy oils from tar sands, is gaining increasing commercial importance. The cracking processes currently used in the refining industry are reviewed. Emphasis is placed on their application to metal-and asphaltene-containing heavy oils. Feed pretreatment by solvent deasphalting is discussed and the manufacture of syncrude from tar sands is considered. New developments for conversion of heavy oils are outlined. The future production of shale oil and of transportation fuels from oil shale is briefly treated.     

Photochemical studies of rancidity: Induction period of protected and non-protected oils

The induction period of an oil is appreciably lengthened when the oil is kept in the dark, and it is likewise lengthened when oils are protected from light by a green wrapper delimited by 4,900 to 5,800 Ångström units. An oil which has been protected from light for a certain period and then exposed to light will develop rancidity in about the same time as will a fresh sample of the same oil exposed to light under the same conditions. The development of peroxides in oils protected from light by means of a green wrapper is no indication of the rate at which rancidity will develop in unprotected oils. The idea heretofore held that the time required for rancidity to develop is associated with the peroxide value is no longer tenable, except in the case of accelerated tests. The results indicate that rancidity of an oil has no necessary correlation with the development of peroxides. A high peroxide value in an oil does not mean that the induction period will be short. This is especially true if the oil has been adequately protected from light. The time required for an oil which has been protected from light to become rancid is, under like conditions, the same regardless of the acquired peroxide value. There is apparently a relationship (see Table IV) between the numerical increase in the peroxide value of an oil previously protected from the time it is exposed to light until it becomes rancid and the peroxide value of a fresh sample of the same oil when it becomes rancid.     

Sensory stability of canola oil: Present status of shelf life studies

Sensory studies on autoxidation of canola oil, stored under several variations of Schaal Oven test conditions, suggest an induction period of 2–4 d at 60–65°C. Similar induction periods have been observed between canola and sunflower oils, whereas a longer induction period has been found for soybean oil. Canola oil seems to be more stable to storage in light than cottonseed and soybean oils but is less stable than sunflower oil. Storage stability of products fried in canola oil is similar to products fried in soybean oil. Storage stability of canola and cottonseed oils that had been used in the frying of potato chips showed that canola oil was more prone to autoxidation during storage at 40°C. The presence of light aggravated the oxidative effects and was similar for both oils. Advances in our knowledge about the shelf life of canola oil would be strengthened by standardization of Schaal Oven testing conditions and by specifying the testing protocol for photooxidation studies. Methods for training of panelists and for handling and evaluating oils and fried foods require definition. Rating scales used in the evaluation of oils need to be evaluated to ensure that reliable and valid measurements are achieved. Further progress is needed in the identification of chemical indicators that can be used to predict sensory quality of oils. Presented in part at AOCS Annual Meeting in Toronto, Ontario, Canada, May 1992.     

Chemical Composition and Oxidative Stability of Selected Plant Oils

Scientific data on the oxidative stability of borage oil, Camelina sativa oil, linseed oil, evening primrose oil and pumpkin seed oil are scarce. Chemiluminescence (CL) methods most commonly used to determine the oxidative stability of oils include measurement of hydroperoxide, intensity of light emitted during the accelerated oxidation process performed at high (>100 °C) temperatures or assisted by forced flow of air/oxygen through the sample. The aim of this study was to investigate the chemical composition and oxidative stability of selected vegetable oils available on the Polish market. Oxidative stability was determined using a fast, novel chemiluminescence-based method, in which light emitted during oxidation process conducted at 70 °C in the presence of some catalyzing Fe²⁺ ions is measured. A reaction of the applied type has not been reported so far. High contents of tocopherols and phytosterols were found in the analyzed oil samples. Oxidative stability of the samples was in most cases higher than the stability of refined rapeseed oil, a relatively stable substance from the oxidation point of view.     

Oxidative stability of flax and hemp oils

Oxidative stability of flax and hemp oils, and of flax and hemp oils stripped of their minor components, was evaluated in the dark at 60°C and under fluorescent light at 27°C. Several analytical methods were used to assess the oxidative stability of oils. Oil extracts were also investigated for their scavenging of 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and for their total phenolic contents. The results indicate that bioactive constituents of these edible oils play a major role in their oxidative stability. However, the FA composition of the oils and their total content of tocopherols as well as the type of pigments present contribute to their stability. Nonstripped flax and hemp oils were more stable than their corresponding stripped counterparts. Furthermore, nonstripped hemp oil had a higher oxidative stability than nonstripped flax oil as evidenced by scavenging of DPPH radical and consideration of total phenolic contents.