非晶态硅酸盐微观结构的研究进展

总结了目前对非晶态硅酸盐微观结构的认识。综述了硅酸盐的分子动力学模拟技术的最新发展以及Raman光谱研究的最新结果。在简要叙述了其它的实验研究手段的基础上,将Raman光谱与它们进行了简单比较,阐明了Raman光谱在硅酸盐微观结构研究方面的优越性,总结了该研究领域需要进一步研究的内容。     

无石棉密封材料蠕变松弛性能的研究进展

本文综述了国内外无石棉密封材料蠕变松弛性能的研究状况,着重阐述了国内外学者在理论研究和实验研究方面取得的成果。虽然对无石棉密封材料做了大量的研究,但许多理论都是建立在近似的基础上,没有通用的模型及本构方程。最后,提出了该领域未来的研究发展方向。     

紫花苜蓿中黄酮类化合物分离及特殊显色反应研究

本研究旨在分离紫花苜蓿中的黄酮类化合物,并进行特殊显色反应相关研究。研究人员通过植物采集和样品制备,获得了紫花苜蓿的植物材料。研究人员采用萃取方法和分离富集方法,成功地从植物材料中提取出黄酮类化合物。其中,柱色谱技术和液液萃取是本研究中主要的分离富集手段。通过黄铜色素的纯化步骤,获得了高纯度的黄酮类化合物。在黄酮色素的紫外光谱分析中,实验过程中采用了先进的光谱技术,得到了详细的实验结果。通过实验结果的分析,确定了所得黄酮类化合物的结构和纯度,为后续研究奠定了坚实的基础。综合研究结果,本研究成功地实现了紫花苜蓿中黄酮类化合物的分离、富集和特殊显色反应的研究目标。所获得的高纯度黄酮类化合物为进一步的生物活性研究提供了有力的实验基础,为紫花苜蓿及相关植物资源的开发利用提供了重要的科学依据。     

上海石化PTT产业链研发和产业化进展

详细介绍了中国石化上海石化股份有限公司1,3-PDO、PTT及其产品的研发情况。具体研究内容有:1,3-PDO的研发,PTT聚合研究,包括催化剂的筛选、反应温度控制、缩聚研究、副反应研究等;PTT聚合物加工性能研究,包括非等温结晶行为研究、热稳定性研究、流变性及可纺性研究等;PTT纤维的纺织、染整研究。石化公司在研发基础上,完成了8000t/aPTT连续试验装置改造的初步设计和施工设计,并用壳牌公司切片生产了6.5t的136.7dtex/24fPTT/FDY。     

高校转型发展背景下有机化学实验教学改革研究

指出了项目研究的目的意义,分析了国内外研究现状,提出了项目研究与改革的目标、内容、拟解决的关键问题和总体实施方案,简要报道了项目研究取得的成效。     

T型通道内气液两相流相分离研究进展

回顾了气液两相流在T形处相分离研究的起因,阐述了对其研究的意义。从实验研究方面着重介绍了不同因素对T型通道内气液两相流相分离的影响。在模型研究方面,介绍了目前为止的3种模型化方法,简单阐述利用数值模拟(CFD)方法研究气液两相流相分离的情况,指出了T型通道内气液两相流相分离的研究难点,并且对该领域今后的主要研究方向进行了展望。     

碳酸钙粉体改性研究进展

碳酸钙粉体改性是提高碳酸钙复合材料整体性能的有效途径之一,国内外材料工作者做了大量的研究。综述了近年来碳酸钙粉体改性研究现状及其改性效果,展望了碳酸钙粉体改性研究领域的发展前景,提出了今后的主要研究任务。     

受体模型在环境空气中大气颗粒物源解析研究进展

介绍了国内外用于大气颗粒物源解析研究的受体模型的进展,对受体模型的研究体系,研究方法作了简单地阐述,并简单概括了研究方法的优缺点及发展趋势。     

纳米改性沥青材料在路面工程中的应用研究现状

将纳米材料掺入至基质沥青中能实现微观层面的性能优化,有效提升沥青路面的路用性能,故纳米改性沥青的研究越来越受到关注。该文总结了纳米改性沥青的研究现状及进展,从改性沥青、改性沥青混合料两方面研究出发,阐述了纳米改性沥青的性能优势;并根据国内外现有研究,概述了纳米改性沥青的关键性问题及研究不足之处,提出了纳米材料改性沥青未来研究的方向及应用前景。     

等离子体裂解煤制乙炔技术的研究进展

回顾了国内外等离子体裂解煤制乙炔的研究概况,介绍了国内近年来在理论研究和试验研究方面取得的进展,分析了该工艺的经济效益和社会效益,对等离子体裂解煤制乙炔主要技术瓶颈和成果进行了讨论,提出了下一步的研究方向。     

反应型肉味香精的制备

本文简要综述了反应型肉味香精的制备过程,介绍了影响反应型肉味香精的特征及风味的要素。     

Flavor components of olive oil—A review

The unique and delicate flavor of olive oil is attributed to a number of volatile components. Aldehydes, alcohols, esters, hydrocarbons, ketones, furans, and other compounds have been quantitated and identified by gas chromatography-mass spectrometry in good-quality olive oil. The presence of flavor compounds in olive oil is closely related to its sensory quality. Hexanal, trans-2-hexenal, 1-hexanol, and 3-methylbutan-1-ol are the major volatile compounds of olive oil. Volatile flavor compounds are formed in the olive fruit through an enzymatic process. Olive cultivar, origin, maturity stage of fruit, storage conditions of fruit, and olive fruit processing influence the flavor components of olive oil and therefore its taste and aroma. The components octanal, nonala, and 2-hexenal, as well as the volatile alcohols propanol, amyl alcohols, 2-hexenol, 2-hexanol, and heptanol, characterize the olive cultivar. There are some slight changes in the flavor components in olive oil obtained from the same oil cultivar grown in different areas. The highest concentration of volatile components appears at the optimal maturity stage of fruit. During storage of olive fruit, volatile flavor components, such as aldehydes and esters, decrease. Phenolic compounds also have a significant effect on olive oil flavor. There is a good correlation between aroma and flavor of olive oil and its polyphenol content. Hydroxytyrosol, tyrosol, caffeic acid, coumaric acid, and p-hydroxybenzoic acid influence mostly the sensory characteristics of olive oil. Hydroxytyrosol is present in good-quality olive oil, while tyrosol and some phenolic acids are found in olive oil of poor quality. Various off-flavor compounds are formed by oxidation, which may be initiated in the olive fruit. Pentanal, hexanal, octanal, and nonanal are the major compounds formed in oxidized olive oil, but 2-pentenal and 2-heptenal are mainly responsible for the off-flavor.     

A review of soybean oil reversion flavor

Crude soybean oil has a characteristic “greenbeany” flavor, which during refining, bleaching and deodorization is eliminated to produce a bland tasting, light colored oil. However, flavor returns during storage and has been characteristically called the “reversion flavor” of soybean oil. This deleterious characteristics flavor has influenced the utilization of soybean oil and its fatty acids. Several theories for the cause of reversion flavor include: (a) oxidation of linolenic acid; (b) oxidation of isolinoleic acid of the 9,15-diene structure; (c) phosphatide reactions; (d) unsaponifiables; and (e) oxidative polymers. References are presented that support or contradict these theories. Recent publications concerning the isolation and characterization of the components of reversion flavor indicate slight oxidation of the fatty acids is the major cause. Techniques that are effective in increasing the flavor stability of soybean oil are presented.     

铁观音茶梗颗粒在卷烟滤嘴中的应用初探

通过SEM和顶空-SPME-GC-MS方法对铁观音茶梗进行了分析,并结合卷烟感官质量评价对铁观音茶梗颗粒在卷烟滤嘴中的应用可行性进行了初步探讨,结果表明:①铁观音茶梗颗粒具有疏松多孔结构,有利于截留烟气中的气溶胶粒子;②铁观音茶梗颗粒中含有与烟草致香成分相同的物质;③铁观音茶梗颗粒能够与烟草自身的香味协调,具有增补烟香、改善卷烟抽吸品质的作用。     

A simplified and precise flavor evaluation procedure for determining oxidative rancidity in vegetable oils

High correlations were observed between the flavor evaluation procedure and objective chemical tests for measuring oxidative deterioration in stored corn, cottonseed, safflower, and soybean oils. The high correlations observed are believed to result from the precision of the flavor threshold testing procedure. Therefore, when suitable flavor testing methods are employed, the chemical methods become more valuable in assessing the quality of an oil. Milk is recommended as the testing media because of its desirable properties. Technical Paper No. 1833, Oregon Agricultural Experiment Station, Corvallis.     

缓控释技术在香料香精领域的研究进展

介绍了国内缓控释技术在香料香精领域中的应用及研究进展。香料香精被广泛应用于食品、纺织印染、医药、涂料等领域,但由于香精有挥发性强、留存时间较短等缺点,限制了其使用范围,因此需采用缓控释技术将香精制备成缓释剂型,从而控制其释放。     

肉桂醛在香精香料、日用化学品及食品添加剂行业中的应用

肉桂醛具有杀菌、保鲜、除臭等功能以及良好的持香作用,因此广泛应用于香料、制药、日化及添加剂等领域,本文重点阐述了肉桂醛在香精香料、日用化学品及食品添加剂方面的应用。肉桂醛的广泛应用决定其具有十分广阔的发展前景。     

Effects of high temperature storage upon lard as a raw material for shortening manufacture

Summary Storage of lard at 95°F. with the resultant development of peroxides had a detrimental effect on its flavor. Colors of the stored lards after deodorization were considerably darker than those of the fresh, and the flavor stabilities of the former were poorer. Partial hydrogenation did not stabilize the aged lards nearly as markedly as the fresh lards. The former had darker colors, lower A.O.M.’s, and poorer flavor stabilities. Presented at the 27th annual fall meeting, American Oil Chemists’ Society, Nov. 2–4, 1953, in Chicago, Ill.     

Improvement of the Flavor and Oxidative Stability of Walnut Oil by Microwave Pretreatment

Walnut oil is in great demand due to its high nutritional value. However, it is easily oxidized and often loses its typical flavor. This study focused on the role of microwave pretreatment in improving the flavor and oxidative stability of walnut oil, and also investigated the effects of microwave pretreatment on unsaturated fatty acids (oleic, palmitoleic, linoleic, and linolenic acids) and antioxidant components (tocopherols and phytosterols). The results indicate that microwave pretreatment is effective in generating pyrazine compounds. The typical ‘roasted’ flavor was present when pretreatment for 2 min or more was applied. Meanwhile, compared with the control sample, only the highly treated sample (microwave‐pretreated for 4 min) showed higher oxidative stability. Only small changes were found in the composition of the unsaturated fatty acids, while the levels of tocopherols and phytosterols significantly decreased with increasing duration of microwave treatment (P < 0.05). The results suggest that the Maillard reaction caused the improvement of oxidative stability, since this reaction can also generate antioxidant products (melanoidins) in addition to pyrazines. Moreover, microwave pretreatment was found to be effective for enhancing the oil yield during pressing. Therefore, despite its adverse effects on tocopherols and phytosterols, microwave pretreatment could be used to improve the flavor and oxidative stability of walnut oil.