HT—1型钛材焊缝坡口清洗膏的研制及其效果分析

本文为钛设备特殊部位或结构的清洗而研制出适合于爆缝坡口的清洗膏，实验证明，该清洗膏能有效地清除钛材料坡口氧化膜，提高焊接质量。     

建筑陶瓷生产用印膏的研制

利用羧甲基纤维素钠（Na—CMC）、甘油、乙二醇和纯净水等为主要原料制备建筑陶瓷生产装饰用印膏，实验研究了工艺因素对印膏粘度和印刷性能的影响，优化出适合生产使用的印膏配方。结果表明：当Na-CMC的加入量在1．75g～2．25g之间，甘油15g，乙二醇20g，纯净水65g所制备的印膏具合适粘度和良好的印刷性能。     

高效液相色谱法测定剑麻皂苷元的含量

以乙腈-水(90∶10)溶液为流动相,检测波长为225 nm,建立了高效液相色谱法测定剑麻皂苷元的方法。结果表明,剑麻皂苷元在4.8²4μg范围内线性相关,回归方程:Y=6 186.312 5X-14 660.1,R2=0.985 48。精密度实验RSD为0.013%,稳定性实验说明在11 h内稳定,重复性实验RSD为0.062%,加标回收率实验平均回收率为96.2%,样品中剑麻皂苷元的含量为0.571 2 mg/g,此方法操作简便、准确、可靠,可为剑麻皂苷元的质量检测提供依据。     

剑麻麻膏水解工艺研究

以剑麻麻膏为原料，水为溶剂，采用浓硫酸酸解法制备水解物，考察了水解时间、硫酸质量浓度、麻膏与浓硫酸质量比对水解收率及水解物含量的影响。以高效液相色谱为检测手段，通过单因素和正交设计实验确定了水解的最佳工艺条件：水解时间8h，硫酸质量浓度15%，麻膏与浓硫酸质量比1∶1。在此条件下水解物收率68.56%，水解物含量12.55%。     

无铅焊膏在电子封装组装中的应用

随着人们对环境的日益重视和电子封装组装焊接技术的发展，合金焊膏的无铅化和质量的要求越来越高，开发无铅、无毒焊膏成为焊膏开发的重要方向，本文论述了几种无铅焊膏Sn-Ag系，Sn-Bi和Sn-Zn系的特点，同时，也检测和评价了一种Sn-Ag免洗焊膏，其绝缘抗阻性，抗腐蚀性，产品清洁度和产品可靠性等均符合要求。     

自动落膏系统改造

分析了原落膏系统的存在问题，运用新的思维进行有针对性的设计，解决了生产中存在的实际问题。     

氟石膏的综合利用

对氢氟酸生产中的副产品氟石膏的性质进行了介绍，综述了氟石膏目前在我国的综合利用现状，并对未来氟石膏的利用提出了展望。     

水葫芦叶绿素面膜膏的研制

文章利用水葫芦叶固有鲜亮绿色富含叶绿素这一特性,在最佳工艺条件下提取叶绿素来制备营养保湿面膜膏。以较简单的配方为原则,选择在面膜膏中应用较为广泛的原料进行叶绿素面膜膏的试制。通过正交实验,找出一个具有最佳面膜膏的基础配方来调配面膜膏,并对该产品的理化指标进行检测和产品使用效果进行评价。     

稳定的三相混合体系的生成研究—用广东白瓷土制备清洁膏

我们实验室已成功制备出由白瓷土、油性功能组份及活性物质水溶液组成的高稳定性膏状清洁上光剂。本文结合制备工艺条件,通过对产品稳定性影响的实验结果,讨论了如何获得高分散、高稳定的油-水-固三相体系的一些规律。     

关于新标准的几点看法

GB8372-2001是在GB8372—1995基础上修订的，但笔者认为仍存在如下不便操作之处。     

Oxidation of acylglycerols and phosphoglycerides by soybean lipoxygenase

Lipoxygenase (EC 1.13.11.12) catalyzes the incorporation of oxygen into polyunsaturated fatty acids, resulting in the formation of their corresponding hydroperoxides. The ability of a commercial preparation of soybean (Glycine max L. Merr.) lipoxygenase to catalyze the oxidation of acylglycerols and phosphoglycerides was investigated. The oxidation rate of trilinolein increased nearly 100% when 5 mM deoxycholate was added to the reaction medium. With further increases in the concentration of deoxycholate, the oxidation rate decreased slightly. The pH profile of trilinolein oxidation was bell-shaped. The rate of oxidation was maximal at pH 8, and it decreased to near zero at pH 5 and pH 11. Even under optimal conditions, the rate of trilinolein oxidation was only 3% of that of linoleic acid, and analysis of time course data showed that, at most, 15% of available linoleate was oxidized. In contrast to the slow rate of trilinolein oxidation, tested phosphoglycerides and diacylglycerols were oxidized at moderate rates. The rate of phosphoglyceride oxidation depended upon the structure of the polar head group and varied between 7–28% of the rate of linoleic acid oxidation. Diacylglycerols reacted at a rate that was 40% of that of linoleic acid. Analysis of the time course of 1,3-dilinolein oxidation showed that as much as 67% of the available linoleate could be converted to the corresponding hydroperoxide. Analyses by high-performance liquid chromatography revealed that more than 20% of the 1,3-dilinolein was converted to unidentified products that are not hydroperoxides.     

Trapping the western pine beetle at and near a source of synthetic attractive pheromone Effects of trap size and position

Western pine beetles were caught on unbaited sticky traps placed near a source ofexo-brevicomin, frontalin, and myrcene. Size of trap, distance and direction from the source of attractant, and height from the ground were varied. Significant differences in trap catch were observed in relation to each of the variables. Traps close to the source of attractant caught more beetles than traps farther from the source. Traps downwind of the source of attractant caught more beetles than did upwind traps. More males than females were trapped close to the source of attractant.Based in part on a thesis submitted by the senior author to the University of California, Berkeley, California, in partial fulfillment of the requirements for the degree Master of Science in entomology, December 1976. These studies were supported by the U.S. Forest Service and in part by the Rockefeller Foundation and a joint grant (NSF GB-34718/BMS 75-04223) from the U.S. National Science Foundation and the U.S. Environmental Protection Agency to the University of California. The findings, opinions, and recommendations are not necessarily those of the University of California or the funding agencies.Trade names and commercial enterprises or products are mentioned solely for information and do not constitute endorsement by the U.S. Department of Agriculture or University of California.     

Breakage patterns of agglomerates

The experimental information available in the literature regarding the patterns of breakage of agglomerate materials is scarce, particularly in dynamic loading. The primary objective of this paper is to present our findings on the breakage patterns of the agglomerates and the interparticle bond. A high-speed digital video imaging technique is used here to gain an insight into the impact behaviour of individual agglomerates against a target plate. Several breakage patterns are observed. Agglomerates may suffer localised damage only, with the disintegration of the damaged zone into very fine debris, or localised damage combined with fracture. The frequency of occurrence of these patterns depends on the impact velocity and agglomerate structure. The pattern of breakage affects significantly the size distribution of the impact product. An investigation of the breakage of individual interparticle bonds is also presented. Two forms of failure are observed, internal (cohesive) and interfacial (adhesive) failure. The morphology of the fractured surface depends greatly on the type of breakage. Internal breakage shows irregular surfaces due to crack jumping, whereas interfacial failure produces clean, smooth fracture surfaces. These observations should provide the necessary foundation for the development of a fundamental model of agglomerate breakage.     

Distribution of birch (Betula SPP.), willow (Salix SPP.), and poplar (Populus SPP.) secondary metabolites and their potential role as chemical defense against herbivores

Isoprenoids and phenolics, major metabolites of important browse species, are reviewed in regard to concentrations, distribution within tissues, and between species. Seasonal variation of specific substances and changes with age of the plant are also considered. The distribution of substances may affect food selection and feeding behavior of animals. Wild mammalian herbivores tend to avoid plant parts rich in these substances, in spite of high nutritional content of the plant tissue. Possible mechanisms for defense by plants against depredation by mammalian herbivores are discussed within the framework of the plants' biochemistry.     

Charakterisierung von Suspensionen nanoskaliger Partikel mittels Ultraschallspektroskopie und elektroakustischer Methoden

Technical control over dispersions with particles in the nanometer size realm should bring about a boost in innovations for some parts of industry. Requirements for the development of these new products is the accurate characterization of the various materials systems. A characterization should always include a determination of the particle size distribution, since it is coupled to the specific effects of these systems. Ultrasound measurement techniques and electroacoustics are two if the available techniques that allow determination of the size distribution and zeta potential of particles with dimensions up to 10 nanometers. A further fundamental advantage of the method is the possibility of carrying out measurements in high‐concentration materials systems. This report describes ultrasound spectroscopy for the measurement of fine‐ and very‐fine‐dispersion particles, and the known theoretical concepts for the interpretation of spectra. In addition, experiences in the use of currently available measurement techniques are presented.     

Mechanical Means of Enhancing Drying Rates: Effect on Drying Kinetics and Quality

The effect of various pretreatments on drying kinetics as well as quality parameters of selected vegetables and fruits was studied experimentally in a convective dryer. The pretreatments tested include application of pinholes and drilled holes of different diameters and densities, blanching and freezing. Potato, cassava, dragon fruit and red chilli were used as the sample drying materials. As expected, increase of the diameter and density of the holes under fixed drying conditions increased the drying rate. Samples with drilled holes showed better drying performance than those with pinholes. The improvement of the drying rate was found to be dependent on the physical properties and the initial moisture content of the material. Results show that the drying performance of the products that possess a skin of low moisture diffusivity, such as chilli, can be improved significantly by blanching and making perforations in the skin. Overall changes of color and volume shrinkage during drying of the samples with and without holes were similar. The effect of different modes of heat input, such as convection, conduction and radiation, on the drying performance of the treated samples was also experimentally investigated. On-off type controllers were used to regulate the power of the heaters and maintain the product temperature within a range of pre-set values. Convection combined with radiation displayed the highest drying rate.     

Inorganic/organic nanocomposite coatings: The next step in coating performance

Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.     

燃煤烟气中单质汞吸附与氧化机理研究进展

燃煤电厂汞排放控制是当前的研究热点,实现燃煤烟气中汞的脱除涉及两个非常重要的过程：吸附与氧化。本文概述了汞在吸附剂表面吸附的相关理论和单质汞的催化氧化机理,结合碳基和非碳基吸附剂相关吸附特性的研究现状,对汞的吸附机理进行了讨论,回顾了SCR、碳基、以及金属和金属氧化物三种常见催化剂对单质汞的催化氧化性能并总结了其可能存在的机理。指出吸附剂表面活性位是决定其对汞吸附效果的关键因素,异相反应是单质汞氧化的重要途径,吸附和氧化是相辅相成的,不同催化剂不同气氛下氧化机理不同。并提出通过氯化物等物质改性能够提高吸附剂的吸附效果,深入研究汞的异相反应机理并开发经济有效的汞脱除方法是今后的研究方向。     

Effect of Dose and Administration Period of Seed Cake of Genetically Modified and Non-Modified Flax on Selected Antioxidative Activities in Rats

Flaxseed cake containing antioxidants is a valuable dietary component. Its nutritional effect may be diminished by the presence of anti-nutrients. The work was aimed at determining the effect of different contents of flaxseed cake in diets and their administration period on the development of rats and selected parameters of their health status. Diets with 15% and 30% addition of genetically modified (GM) flax seed cake with enhanced synthesis of polyphenols, as well as Linola non-GM flax were administered in short-term (33 days) and long-term (90 days) experiments. The 30% addition of flaxseed cake reduced digestibility of dietary nutrients, GM flaxseed cake lowered body weight gains. The relative weight of selected organs, hematological blood markers and serum activities of aspartate and alanine aminotransferases (AST, ALT) were not affected. Flaxseed cake consumption reduced serum concentration of albumins and increased globulins. Administration of 30% flaxseed cake improved plasma total antioxidant status and 30% GM flaxseed cake lowered liver thiobarbituric acid reactive substances. The activities of superoxide dismutase in erythrocytes, glutathione peroxidase in plasma and the liver concentration of 8-oxo-2′-deoxyguanosine were not changed. Most morphometric parameters of the small intestine did not differ between feeding groups. The administration of diets with 30% addition of flaxseed cake for 90 days improved the antioxidant status in rats.     

Emerging role of nanobiocatalysts in hydrolysis of lignocellulosic biomass leading to sustainable bioethanol production

Catalytic conversion (hydrolysis) of carbohydrate polymers present in the lignocellulosic biomass into fermentable sugars is a key step in the production of bioethanol. Although, acid and enzymatic catalysts are conventionally used for the catalysis of various lignocellulosic biomass, recently application of immobilized enzymes (biocatalysts) have been considered as the most promising approach. Immobilization of different biocatalysts such as cellulase, β-glucosidase, cellobiose, xylanase, laccase, etc. on support materials including nanomaterials to form nanobiocatalyst increases catalytic efficacy and stability of enzymes. Moreover, immobilization of biocatalysts on magnetic nanoparticles (magnetic nanobiocatalysts) facilitates easy recovery and reuse of biocatalysts. Therefore, utilization of nanobiocatalysts for catalysis of lignocellulosic biomass is helpful for the development of cost-effective and ecofriendly approach. In this review, we have discussed various conventional methods of hydrolysis and their limitations. Special emphasis has been made on nanobiocatalysts used for hydrolysis of lignocellulosic biomass. Moreover, the other most important aspects, like nanofiltration of biomass, conversion of lignocellulose to nanocellulose, and toxicological issues associated with application of nanomaterials are also discussed.