浅析数字电视发射机技术及应用

数字电视系统的核心叫做数字电视发射机,包括八个方面的技术应用:激励器的技术应用、无线传输技术应用、数字预失真技术应用、低相噪捷变频技术应用、数字微波传输系统的技术应用、功率加大器的技术应用、电视差频转播技术应用和冷却功能的技术应用,文章详细讲解了各种技术,并分三种方向提出了数字电视发射机技术在实际应用中需要考虑的事项。     

我国木工刀具材料发展概况

文章对我国木工刀具应用材料概况进行了论述,并针对目前应用的工具钢、高速钢、硬质合金、陶瓷材料、聚晶材料等具体材料的发展应用过程、分类和性能特点进行了详细论述,根据刀具应用材料的发展和应用的现状预测了木工刀具材料未来发展趋势     

现代服装CAD技术应用与发展的特点

论述了现代CAD技术在服装领域的应用和发展趋势,探讨了服装CAD技术应用品牌、应用能力、应用弊端等方面的问题。     

膜分离技术及其在食品工业中的应用

主要介绍了膜分离技术的发展现状及其应用在食品工业与传统工艺相比的优点、各种膜分离过程的定义和基本原理、膜组件的结构及应用特性、膜分离技术的选择及系统的方案设计、在食品工业中的应用实例以及新的膜分离技术在食品工业中应用前景、展望等。通过与传统工艺的比较和分析,许多应用实例表明,膜分离技术在工业中的应用改变了食品工业传统落后的生产工艺,节省了能源,提高了产品质量,有着极为广阔的应用发展前景。     

甘草甜素和甘草黄酮的功能和应用

综述了甘草的主要组分甘甜素和黄酮类物质在食品、医学上的应用、介绍了甘草的其他应用,展望了其应用前景。     

造纸工业用变性淀粉现状及发展趋势

论述了变性淀粉在造纸工业中的应用,重点介绍了应用广泛的变性淀粉的种类、性能、应用机理及发展趋势.     

电大VisualBasic程序设计与应用

本文首先介绍了电大开放教育《vistlalBasic程序设计与应用》的背景,继而分析了此程序设计与应用基本思路,然后以列表框控件为例,从程序设计与应用目标、内容、预习、面授、复习等方面对VisualBasic程序设计与应用进行了研究。     

酶在制革中的应用

回顾了酶制剂在制革中应用的历史,介绍了酶制剂在制革过程中的浸水、脱毛、脱脂、浸灰、软化、猪皮臀部包酶及对制革废料处理等方面的应用情况和一些典型酶制剂的应用性能,并对酶制剂在制革中应用的发展趋势进行了展望。     

大豆蛋白在主食中的应用

综述了大豆蛋白产品-大豆蛋白粉、大豆分离蛋白、大豆浓缩蛋白、大豆组织蛋白在主食馒头、面包、面条中的应用现状,提出了其应用中存在的问题,并对应用前景进行了展望。     

紫外线杀菌在食品工业中的应用

本文讨论了紫外线杀菌的原理及特点,并对其在食品工业中应用的主要问题、设备设计、应用范围及应用潜力进行了探讨。     

Encapsulation of food ingredients

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.     

STANDARD SIZING AND FIT TESTING APPLIED TO WOMEN'S HOSIERY

The monograph deals with a critical review of the recent research work and development on ramie, a long vegetable bast fibre. The review is divided into two parts. Part I discusses the progress of recent work on ramie, chemical components like fibre degumming, its effects on fibre composition, chemical constituents, i.e. hemicellulose, cellulose, non-cellulosic and mineral matters. Besides various chemical properties of native and modified fibres such as accessibility, infrared, cellulose I–V, DP, grafting, cross linking and resin finishing and dyeing etc. are dealt with.     

5—THE CONSTITUTION OF THE EPICUTICLE OF WOOL

Epicuticle, isolated from wool via the Allwörden reaction, was examined by electron microscopy and analysed chemically. It is proteinaceous; lipids and carbohydrates could not be detected. The component amino acids are: cystine, glycine, glutamic acid, serine, valine, alanine, lysine, α-amino-adipic acid, and threonine. A tentative model for the epicuticle is proposed.     

Mycotoxins in botanicals and dried fruits: A review

Botanicals are used in many countries for medicinal and general health-promoting purposes. Numerous natural occurrences of mycotoxins in botanicals and dried fruits have been reported. Aflatoxins or ochratoxin A (OTA) have been found in botanicals such as ginseng, ginger, liquorice, turmeric, and kava-kava in the USA, Spain, Argentina, India, and some other countries, while fumonisins have been found in medicinal wild plants in South Africa and in herbal tea and medicinal plants in Turkey. Zearalenone was identified in ginseng root. Dried fruits can be contaminated with aflatoxins, OTA, kojic acid, and, occasionally, with patulin or zearalenone. One main area of concern is aflatoxins in dried figs; bright greenish yellow fluorescence under ultraviolet light is associated with aflatoxin contamination. OTA in dried vine fruits (raisins, sultanas, and currants) is another concern. There are also reports of aflatoxins in raisins and OTA in dried figs, apricots, dried plums (prunes), dates, and quince. Maximum permitted levels in the European Union include 4 µg kg^-1 for total aflatoxins in dried fruit intended for direct consumption and 10 µg kg^-1 for OTA in dried vine fruit. This review discusses the occurrence of mycotoxins in botanicals and dried fruits and analytical issues such as sampling, sample preparation, and methods for analysis. Fungal contamination of these products, the influence of sorting, storage, and processing, and prevention are also considered.     

Avena sativa (Oat), A Potential Neutraceutical and Therapeutic Agent: An Overview

The aim of the present review article is to summarize the available information related to the availability, production, chemical composition, pharmacological activity, and traditional uses of Avena sativa to highlight its potential to contribute to human health. Oats are now cultivated worldwide and form an important dietary staple for the people in number of countries. Several varieties of oats are available. It is a rich source of protein, contains a number of important minerals, lipids, β-glucan, a mixed-linkage polysaccharide, which forms an important part of oat dietary fiber, and also contains various other phytoconstituents like avenanthramides, an indole alkaloid-gramine, flavonoids, flavonolignans, triterpenoid saponins, sterols, and tocols. Traditionally oats have been in use since long and are considered as stimulant, antispasmodic, antitumor, diuretic, and neurotonic. Oat possesses different pharmacological activities like antioxidant, anti-inflammatory, wound healing, immunomodulatory, antidiabetic, anticholesterolaemic, etc. A wide spectrum of biological activities indicates that oat is a potential therapeutic agent.     

Bioactivation of Phytoestrogens: Intestinal Bacteria and Health

Phytoestrogens are polyphenols similar to human estrogens found in plants or derived from plant precursors. Phytoestrogens are found in high concentration in soya, flaxseed and other seeds, fruits, vegetables, cereals, tea, chocolate, etc. They comprise several classes of chemical compounds (stilbenes, coumestans, isoflavones, ellagitannins, and lignans) which are structurally similar to endogenous estrogens but which can have both estrogenic and antiestrogenic effects. Although epidemiological and experimental evidence indicates that intake of phytoestrogens in foods may be protective against certain chronic diseases, discrepancies have been observed between in vivo and in vitro experiments. The microbial transformations have not been reported so far in stilbenes and coumestans. However, isoflavones, ellagitanins, and lignans are metabolized by intestinal bacteria to produce equol, urolithins, and enterolignans, respectively. Equol, urolithin, and enterolignans are more bioavailable, and have more estrogenic/antiestrogenic and antioxidant activity than their precursors. Moreover, equol, urolithins and enterolignans have anti-inflammatory effects and induce antiproliferative and apoptosis-inducing activities. The transformation of isoflavones, ellagitanins, and lignans by intestinal microbiota is essential to be protective against certain chronic diseases, as cancer, cardiovascular disease, osteoporosis, and menopausal symptoms. Bioavailability, bioactivity, and health effects of dietary phytoestrogens are strongly determined by the intestinal bacteria of each individual.     

蒽醌助剂对乙二醇溶剂脱胶苎麻纤维性能的影响

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%。     

Influence of different non-grain commodities on the population growth of Trogoderma granarium Everts (Coleoptera: Dermestidae)

We investigated the population growth of the khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae) on seven groups of commercially available non-grain commodities. Six powdered spices were used in the first group of experiments: black pepper, clove, nutmeg, allspice, cinnamon and turmeric. The second group of the tested commodities included seven animal products: powdered cow milk, powdered pork zelatin, sheeps’ wool, goat’s skin, ducks’ feathers, dry dog food and dry cat food. The third group of commodities was consisted of six herbs: oregano, spearmint, basil, coriander, laurel and marjoram. The fourth group of commodities contained ten pulses: chickpeas, lentil, split peas, black-eyed peas, beans, soybean flour and whole kernels, lima beans, mung bean, and broad beans. The fifth group comprised six dried fruits: Corinthian currants, sultanas, banana chips, melons, apricots and figs. The sixth group was consisted of five non-grain commodities: cottonseed cake, tobacco, black tea, Turk kahvesi and potato flour. The seventh group included seven nuts: sunflower seeds, pumpkin seeds, pistachios, roasted chickpeas (yellow), almonds, hazelnuts and walnuts. Finally, six cracked containment categories (0% cracked kernels, 5% cracked kernels and 95% intact kernels, 10% cracked kernels and 90% intact kernels, 25% cracked kernels and 75% intact kernels, 50% cracked kernels and 50% intact kernels and 100% cracked kernels) from five pulses were tested: chickpeas, black-eyed peas, mung bean, soybean and split peas. The highest progeny production (3.01 individuals per vial) was recorded on powdered cow milk. On pistachios, split peas, sunflower seeds, soybean flour, pumpkin seeds, walnuts, almonds and coriander, T. granarium built high population densities rapidly, while on roasted chickpeas, cottonseed cake, hazelnuts, chickpeas, dog food and lentils, its population growth was much less. Broad beans, melons, figs, lima beans, beans, Corinthian currants, pork zelatin and potato flour were less suitable diets for the development of this species. On black pepper, clove, nutmeg, allspice, cinnamon, turmeric, sheeps’ wool, goat’s skin, ducks’ feathers, cat food, sultanas, banana chips, apricots, tobacco, black tea, Turk kahvesi, oregano, spearmint, basil, laurel and marjoram, no progeny production was recorded. The proportion of 100% cracked black-eyed peas or mung beans was more suitable for the population growth of T. granarium. Also, the percentages of 50% cracked chickpeas or 10% cracked soybeans enhanced the development of the species, in comparison with the whole kernels of each pulse. Our study indicated that several non-grain commodities are beneficial for the population growth of T. granarium, a fact that should be seriously taken into account in international trade, as this pest may utilize them as “vehicles” of expansion.     

Detection and characterization of engineered nanoparticles in food and the environment

Nanotechnology is developing rapidly and, in the future, it is expected that increasingly more products will contain some sort of nanomaterial. However, to date, little is known about the occurrence, fate and toxicity of nanoparticles. The limitations in our knowledge are partly due to the lack of methodology for the detection and characterisation of engineered nanoparticles in complex matrices, i.e. water, soil or food. This review provides an overview of the characteristics of nanoparticles that could affect their behaviour and toxicity, as well as techniques available for their determination. Important properties include size, shape, surface properties, aggregation state, solubility, structure and chemical composition. Methods have been developed for natural or engineered nanomaterials in simple matrices, which could be optimized to provide the necessary information, including microscopy, chromatography, spectroscopy, centrifugation, as well as filtration and related techniques. A combination of these is often required. A number of challenges will arise when analysing environmental and food materials, including extraction challenges, the presence of analytical artifacts caused by sample preparation, problems of distinction between natural and engineered nanoparticles and lack of reference materials. Future work should focus on addressing these challenges.     

中美主要烟草品种亲源分析与烟草育种

本文分析了中美300多个烤烟,80多个晒晾烟主要育成品种的亲源关系,从中可以看出,品质与抗病育种是烟草育种的主体,由Orinoco衍生的Hicks、Virginiabrightleaf和400及后来育成的NC95、Coker139和Coker319等是烤烟品质育种和抗病育种的主体亲本;由WhiteBurley衍生的Kentucky16、Burley21和由MDRobinson育成的Maryland64、Maryland609分别是白肋烟与马里兰烟品质、抗病育种的主体亲本;烟草抗黑胫病、青枯病、根结线虫病、根黑腐病、烟草普通花叶病和野火病的抗源分别来自Florida301、TI448A、TI706、N. debnexyi、N. glutinosa和N. longiflora等原始栽培品种或野生种。美国烟草育种经历了从品质到多抗,再到综合优良性状改良的阶梯式发展过程。而我国优质、多抗育种起步较晚,仍存在品质与抗性、品质与易烤性关系研究较少,外源优良基因利用较少,遗传基础狭窄等问题,本文就近期烟草育种的目标和途径进行了初步探讨。