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1.
介绍了积层线路板用紫外光固化油墨的组成和特点以及影响积层线路板紫外光固化油墨性能的各种因素,着重介绍了感光树脂、新型引发剂和高性能单体开发的研究进展。  相似文献   

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研究了积层线路板油墨的组成配方、制备和应用工艺,分析了不同预烘时间对油墨分辨率的影响以及过显和显影不足问题的形成,并从生产和实际操作的角度,提出了解决的方案。利用聚苯醚改性的环氧树脂,应用于油墨的配方中,改善了油墨固化后绝缘材料的耐热性、介电性等主要性能。油墨中改性环氧树脂的质量分数为13.0%时,固化后绝缘材料的玻璃化温度可达184.22℃,介电常数为3.19,介质耗损因数为0.019,可以作高频积层线路板的绝缘层。  相似文献   

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赵兰英 《杭州化工》1997,27(1):33-34
在氯化聚丙稀和氯化的乙烯醋酸乙烯共聚体系列树脂中,加入丙烯酸单体与氯化聚丁二烯及氯化聚烯烃共聚树脂作为连接料制成一种通用的复合印刷用油墨。  相似文献   

4.
《涂料技术与文摘》2006,27(1):43-43
200601237 含胺封端聚氯丙烯的载体涂料及由其制备的印刷介质;200601238 用于漆器、纪念牌和家具的喷墨印刷装饰法;200601239 UV 固化溶剂型喷印油墨;200601240 积层电路板用液态感光绝缘油墨;200601241 可再现肉色的热染料转移标签、标签制备、制备该实用标签用的接受板及中间体。  相似文献   

5.
《涂料技术与文摘》2003,24(2):93-93
0302458光变油墨组合物及其应用: CNI 122 606.引中国发明专利申清公开]/中国:樊官保(樊官 保) 20021023DI 122 606.4(20062); IPC *09Dll川2 0302459环保油墨及其用途: CNI 373 167AI中国发 明专利申盾公开]/…国:张学毅(张学毅)二-2002 109一门门8 5982(2002191);IPC C09Dll /10 0302460喷墨式白色油墨及其二氧化钛浆: CNI 375 529A中国发明专利申请公开]/日本:精工爱普生株 式会什(中材悻澄等).-200210、23.-02 107 094血2002314); IPC C09Dll/02 mm461紫外牛因仆木果讪黑纳…  相似文献   

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陈发生 《油墨通讯》1995,96(2):8-10
油墨被涧版水乳化是平版印刷过程中不可避免的、客观存在的现象,但乳化状况与乳化后油墨的性质是基本可以掌握或加以改进的。本文介绍了我公司油墨乳化的试验方法,并从试验结果得知乳化率在20 ̄40%、乳化前后油墨的流动性变化小于1/3是适宜的。这方法既可为油墨制造厂改进油墨性能的手段,其乳化率等指标亦可为印刷厂在选择油墨品种时作参考。  相似文献   

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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.  相似文献   

12.
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.  相似文献   

13.
Breakage patterns of agglomerates   总被引:4,自引:0,他引:4  
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.  相似文献   

14.
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.  相似文献   

15.
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.  相似文献   

16.
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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
Allelopathic interactions among algae   总被引:1,自引:0,他引:1  
Five species of green algae isolated from the Cleveland County, Oklahoma, area and a commercially obtained yellow-green alga were tested for allelopathic interactions. Axenic cultures ofPandorina morum Bory were stimulated in three sterile filtrates from nonaxenic cultures ofScenedesmus incrassatulus var.mononae G.M. Smith, with the oldest filtrate showing the least stimulation. By measuring the growth of axenic cultures inoculated into sterile filtrates of old cultures, instances of inhibition and stimulation were recorded in three screening experiments.Cosmarium vexatum West filtrate was inhibitory to the five other species, a characteristic probably important in its role of producing waterblooms in ponds and swamps. The allelopathic effects of filtrates of the five other species onBolrydium becherianum Vischer could be a key to its restriction to terrestrial sites. Instances of heat lability of the active substances were noted. These interactions, both allelopathic and stimulatory, probably play a significant role in the succession of algal blooms in nature.  相似文献   

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