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展示了对越南基巧红宝石中包裹体的研究成果. 用光学显微镜检测了这些包裹体的特征. 采用拉曼散射法和扫描电子探针分析了包裹体的成分.在该类红宝石中发现了锐钛矿、红柱石、钙长石、磷灰石、黑云母、一水软铝石、板钛矿、方解石、刚玉、硬水铝石、白云石、石墨、珍珠云母、白云母、金云母、黄铁矿、金红石、锆石、黝帘石包裹体组合. 描述了该类红宝石多相包裹体中气-液相与负晶的成分, 讨论了主晶红宝石的形成条件. 相似文献
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多媒体作为一种现代化的教学手段,创造了图文并茂、动静结合、声情交融的教学环境,巧妙利用声、光、色、形模拟了事物情景,再现了生动的事物画面,从不同程度不断的形成较多的兴奋点,为教学提供了逼真的表现效果,扩大了学生感知的时间与空间,激发了学生的主动性、积极性、创造性,突破了课程中的难点,培养了学生的审美情趣,提高了教师的教学成效。 相似文献
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六种新型纺织纤维的性能及其鉴别 总被引:4,自引:3,他引:1
介绍了Lyoeell、Modal、大豆蛋白纤维、竹纤维、牛奶蛋白纤维、甲壳素纤维的性能并进行了对比。对这六种新型纤维的鉴别方法进行了试验、分析和综述,并与几种易混淆的常规纤维的相应特征进行了区别,提出了有效的鉴别方法。 相似文献
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60年前,为发展民族工业,带动大规模经济建设,北京人民机器总厂诞生了。她的诞生,改变了企业所有制形式,改变了职工身份和地位,实现了北京市的发展规划;她的诞生,缔造了民族印机从铅印到胶印、凹印、表格、柔版、涂布的转变;从品种的单一到产品的系列化、功能化、高效化的发展过程;她的诞生,彰显了企业创业、调整、改革、攻坚、发展的篇章,创造了一个进入中国工业500强、以“北人”牌产品享誉中国的印刷机械制造企业集团。 相似文献
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对墨水的品质控制进行了详细介绍,对墨水的研发、质量、生产、稳定性、可靠性做了介绍,详细介绍了墨水的pH、电导率、粘度、表面张力、色彩等重要指标. 相似文献
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Microencapsulation is a relatively new technology that is used for protection, stabilization, and slow release of food ingredients. The encapsulating or wall materials used generally consist of starch, starch derivatives, proteins, gums, lipids, or any combination of them. Methods of encapsulation of food ingredients include spraydrying, freeze‐drying, fluidized bed‐coating, extrusion, cocrystallization, molecular inclusion, and coacervation. This paper reviews techniques for preparation of microencapsulated food ingredients and choices of coating material. Characterization of microcapsules, mechanisms of controlled release, and efficiency of protection/ stabilization of encapsulated food ingredients are also presented. 相似文献
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为解决苎麻在乙二醇有机溶剂脱胶中纤维易被氧化而导致性能下降的问题,在乙二醇溶剂中添加助剂蒽醌对苎麻进行脱胶,并对蒽醌不同添加量下制得的纤维进行结构和性能表征。结果表明:纤维中半纤维素含量随蒽醌添加量的增加而升高,纤维的聚合度、结晶度、物理力学性能先升高后降低,纤维的残胶率和线密度先降低后升高;当蒽醌质量分数为0.3% 时,这些性能均达到最佳值,此时纤维的聚合度、结晶度、制成率、断裂强度、断裂伸长率、断裂功比不加蒽醌时分别提高了7.32%、20.53%、1.46%、9.55%、6.89%、33.33%,纤维的残胶率、线密度比不加蒽醌时分别降低了17.91%、7.24%。 相似文献
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为解决苎麻氧化脱胶中纤维容易被过度氧化而性能受损的问题,在氧化脱胶液中添加了具有纤维素和半纤维素保护效果的试剂 1,8-二羟基蒽醌(丹蒽醌),并通过调节1,8-二羟基蒽醌的用量实现了对苎麻纤维理化性能(强伸性能、聚合度、半纤维素含量、制成率等)的调控。结果表明,1,8-二羟基蒽醌用量越高,纤维中半纤维素含量、制成率越高;但纤维强伸性能随1,8-二羟基蒽醌含量先升高后降低;当1,8-二羟基蒽醌的用量为2 %时,脱胶的综合效果最佳,此时纤维的断裂功、聚合度、半纤维素含量、制成率比不使用1,8-二羟基蒽醌时分别提高了41.0%、2.0%、17.3%、7.0%;此外,使用1,8-二羟基蒽醌后,脱胶废水的COD值降低了40%,大幅度提高了氧化脱胶工艺的环保性。 相似文献
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In the period between December 5, 1991 and September 17, 1998, 760 maize, 367 wheat, 119 soybean, 222 barley, 85 bran, 32 triticale, 60 oat, 14 rye and 22 sunflower samples were investigated for the presence and concentration of seven fusariotoxins (T-2 toxin, zearalenone, deoxynivalenol, nivalenol, diacetoxyscirpenol, HT-2 toxin, fusarenone-X) and OTA. The comparison of analytical data with those of the relevant literature revealed that although the incidence rate and/ or concentration of Fusarium mycotoxins and OTA in Hungarian-grown cereals is occasionally considerable, the position of the country is not worse than the average of countries. Our findings indicate that soybean tends to be good substrate for trichothecene-producing fungi and the rate of contamination is regarded as substantial. The commodities were assorted into one of three quality categories. The proportion of objectionable samples was only 3.0, 2.2, 2.3 and 1.7% in maize, wheat, barley and soybean samples, respectively. However, this low rate of objection might still be a source of great economic loss. The proportion of objectionable samples was much higher in the case of bran, oat and triticale (7.1, 6.7, and 6.3%, respectively). The results of the present investigation indicate a need for regular screening for mycotoxins of importance and individual appraisal of each commodity from the point of their use in animal feeds. 相似文献
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ABSTRACT: The objective of the present study was to investigate the effects of various parameters, that is, concentration of salt solution (2%, 3%, 4%[w/v]), boiling time (3, 5, 7 min), drying air temperature (80, 100, 120 °C), and size of shrimp, on the kinetics of drying and various quality attributes of shrimp, namely, shrinkage, rehydration ability, texture, colors, and microstructure, during drying in a jet-spouted bed dryer. In addition, the effects of these processing parameters on the sensory attributes of dried shrimp were also investigated. Small shrimp (350 to 360 shrimp/kg) and large shrimp (150 to 160 shrimp/kg) were boiled and then dried until their moisture content was around 25% (d.b.). It was found that the degree of color changes, toughness, and shrinkage of shrimp increased while the rehydration ability decreased with an increase in the concentration of salt solution and boiling time. Size of shrimp and drying temperature significantly affected all quality attributes of dried shrimp. The conditions that gave the highest hedonic scores of sensory evaluation for small dried shrimp are the concentration of salt solution of 2% (w/v), boiling time of 7 min, and drying air temperature of 120 °C. On the other hand, the conditions that gave the highest hedonic scores of sensory evaluation for large dried shrimp are the concentration of salt solution of 4% (w/v), boiling time of 7 min, and drying air temperature of 100 °C. The quality attributes of dried shrimp measured by instruments correlated well with the sensory attributes, especially the color of dried shrimp. 相似文献
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Sheenam Garg Vaibhao Kisanrao Lule Ravinder Kumar Malik Sudhir Kumar Tomar 《International Journal of Food Properties》2016,19(11):2550-2574
Functional foods are the focus of attraction for well-being. The healthy living of Asians may be attributed to a diet enriched with soy isoflavones viz. genistein and daidzein which fills the gap of proteinaceous diet in vegetarians. Several factors, such as administration, dosage, metabolism, ingestion of other pharmacological substances, type of estrogen receptors, and presence or absence of endogenous estrogen, affect the activities and bioavailability of isoflavones. The mode of therapeutic action could be either through the stimulation of estrogen receptors or by the non-involvement of estrogen receptors. Soy, due to its isoflavones content, serves as a balanced and remedial substitute in combating various lifestyle disorders, like cancer prevention, by interruption of the breakdown of extracellular matrix that surrounds growing vessels and tumors, lowering of lipid and blood insulin levels by regulating lipid and glucose metabolism, alleviation of menopausal symptoms, and osteoprotective effects by modulating estrogen receptors, thus acting as a safer switch to hormone replacement therapy, anti-hypertensive effect which may also contribute to cardioprotective, anti-oxidative effect, regulation of cognitive functions, and many others. Therefore, it could be regarded as a valuable therapeutics. However, since soy isoflavones also act as endocrine disruptors, they also possess some negative effects. Concerns have been raised in relation to thyroid function abnormality. In view of the previously mentioned facts an attempt has been made to review the literature available on both beneficial as well as deleterious role of isoflavones, soy derived bioactive compounds. 相似文献
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探讨产地、季节、品种对蛤蜊中金属营养元素含量的影响,解析蛤蜊中金属营养元素含量与养殖地淤泥和海水中相关元素含量间的关系。于2014年5月和9月在青岛市、南通市和大连市海岸采集花蛤、文蛤及养殖地淤泥和海水样品,测定样品中金属营养元素含量,分别进行方差分析和Pearson相关分析。结果显示,蛤蜊中Mg、K、Ca、Mn、Fe、Cu、Zn含量受产地的影响,Ca、Cu、Zn含量受季节的影响,Mg、Ca、Mn、Fe、Cu、Zn含量与品种有关;Na、Mg、Ca、Co、Cu含量与淤泥中相关元素的含量密切相关,而10 种金属营养元素含量与海水中相关元素含量相关性均不显著。本研究表明,蛤蜊中金属营养元素含量受产地、季节、品种的影响,其来源除淤泥、海水外,还有其他途径。 相似文献
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Diane M. Barrett Elisabeth Garcia Jo Ellen Wayne 《Critical reviews in food science and nutrition》1998,38(3):173-258
Knowledge of the textural properties of processing tomatoes is crucial to ensuing product acceptability; measurement, control, and optimization of these properties through judicious selection of varieties and control of unit operations results in products that the consumer prefers. It is important to first define the terms texture, rheology, consistency, and viscosity prior to discussing principles of their measurement. The textural properties of processing tomatoes may be measured using both sensory and objective tests, and the latter may be either destructive or nondestructive in nature. The unique anatomy of tomato fruit (peel, pericarp, columella, and locules) in part dictates the method of texture measurement. Numerous factors, including variety, maturity, genetic modification, cultural particles, and environmental conditions, processing conditions, and calcium addition affect the textural integrity of tomatoes. Textural properties of raw tomatoes and most processed tomato products are reviewed in this article. 相似文献
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以湖北、安徽和四川地区小曲为研究对象,利用传统培养方法和分子生物学方法研究不同地区小曲中可培养细菌的种类。结果表明,湖北小曲pH值为5.35,含水量为9.93%,密度为0.87 g/mL,共分离出8株可培养细菌,其中枯草芽孢杆菌(Bacillus subtilis)6株,泛菌属(Pantoea spp.)及丰年芽孢杆菌(Bacillus toyonensis)各1株;安徽小曲pH值为5.60,含水量为12.33%,密度为0.84 g/mL,共分离出5株可培养细菌,其中植物乳杆菌(Lactobacillus plantarum)3株,埃希氏菌属(Escherichia spp.)及枯草芽孢杆菌(B. subtilis)各1株;四川小曲pH值为5.59,含水量为9.41%,密度为0.92 g/mL,共分离出7株可培养细菌,其中枯草芽孢杆菌(B. subtilis)2株,B. toyonensis、普城沙雷氏杆菌(Serratia plymuthica)、炭疽芽孢杆菌(Bacillus anthracis)、蜡状芽孢杆菌(Bacillus cereus)及Burkholderia fungorum各1株。不同地区小曲中可培养细菌种类差异较大,但3种小曲均有芽孢杆菌属(Bacillus sp.)细菌。 相似文献
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The trace element contents of five varieties of instant coffee powder available in the Indian market have been analysed. Ca, Cr, Fe, K, Mg, Mn, Ni, Sr, Zn and Pb, Cd, Cu have been determined using atomic absorption spectrophotometry and differential pulse anodic stripping voltammetry, respectively. The metal levels in the coffee powders observed in this study are comparable with those reported for green coffee beans (Arabica and Robusta variety) reported worldwide with the exception of Sr and Zn, which were on the lower side of the reported values. Concentrations of these metals have been converted into intake figures based on coffee consumption. The daily intakes of the above metals through ingestion of coffee are 1.4mg, 1.58 mu g, 124 mu g, 41.5mg, 4.9mg, 17.9 mu g, 2.9 mu g, 3.8 mu g, 12.5 mu g, 0.2 mu g, 0.03 mu g and 15.5 mu g, respectively. The values, which were compared with the total dietary intake of metals through ingestion by the Mumbai population, indicate that the contribution from coffee is less than or around 1% for most of the elements except for Cr and Ni which are around 3% . 相似文献