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1.
坭兴陶的成型工艺和其它陶瓷成型工艺大同小异,主要分为手工成型和模具成型两大类,其中手工成型包括手拉成型、拍片镶接成型、盘筑成型等,模具成型包括注浆成型、压坯成型和印坯成型等。  相似文献   

2.
氟塑料加工     
本章概述除聚四氟乙烯模压成型外的其他加工方法。有挤压成型:分柱塞挤压成型、螺旋挤压成型、糊膏挤压成型三种;有等压压缩成型(又称液压成型);有浸渍与涂层成型;有复合成型等,还有二次加工成型;压延成型、切削等机械加工成型、焊接、粘接、衬里、吹塑等等二次加工方法是本章重点叙述的内容。  相似文献   

3.
陶瓷现代成型技术的研究进展   总被引:1,自引:0,他引:1  
分析了成型工艺在陶瓷制备中的重要作用和高质量的陶瓷坯体对成型工艺的基本要求,评述了国内外陶瓷现代成型技术,着重介绍了离心沉积成型、电泳沉积成型、离心注浆成型、注射成型、胶态成型和快速自动成型等新工艺,讨论了上述成型方法的基本原理和特点,指出了陶瓷成型技术的发展思路。  相似文献   

4.
介绍了几种重型汽车用塑料制品成型工艺,主要有注射成型、挤出成型、吹塑成型、压制成型、反应注射成型等成型工艺,重点介绍了在塑料制品成型中占很大比重的注射成型工艺。并举例说明重型汽车用大型塑料制品制备中的注意事项。  相似文献   

5.
周治峰 《辽宁化工》2015,(2):155-157
介绍了常用的固体催化剂成型方法,包括挤条成型、喷雾成型、压片成型,转动成型等。探讨了成型过程对催化剂性能的影响,分析了这些成型方法的成型原理和实际应用。  相似文献   

6.
吴健文 《国外塑料》2010,28(3):49-50,54
阐述了近年来塑料注射成型的一些新技术,包括微型注射成型技术、振动气体辅助成型技术、节能降耗注射成型技术、水辅注射成型技术、簿壁超高速注射成型技术等,并对注塑成型技术的发展前景进行了展望。  相似文献   

7.
吴清鹤  陈金伟 《国外塑料》2006,24(9):66-67,70,71
介绍了近年来气体辅助及其他介质辅助塑料成型的一些新技术,包括振动气体辅助成型技术、多腔控制气辅成型技术、气体辅助共注成型技术、气体辅助挤出成型技术,其他介质成型技术如水辅注射成型技术及液辅成型技术。最后展望了气辅及其他介质成型技术的发展趋势。  相似文献   

8.
树脂基复合材料成型工艺的发展   总被引:5,自引:0,他引:5  
随着复合材料工业的迅速发展,传统的复合材料成型工艺日臻完善,新的成型方法不断涌现。本文通过梳理接触低压成型工艺、拉挤成型工艺、模压成型工艺、缠绕成型工艺、铺放成型工艺、RTM成型工艺这几种先进树脂基复合材料成型工艺的发展历程,分析发展过程中的关键技术,来研究先进复合材料成型工艺的演变,从而探讨未来树脂基复合材料成型工艺的发展方向。  相似文献   

9.
复合材料成型工艺方法主要有缠绕成型、铺放成型、模压成型、热压罐成型以及树脂传递模塑成型等。复合材料成型工艺为重要环节,通常包括两个阶段,首先是使原材料在一定温度和压力下产生变形或流动,获取所需的形状,然后设法保持其形状。本文主要对复合材料模压成型工艺流程、成型模具设计、铺层设计、复合材料构件成型、模压成型工艺特性以及影响模压制品质量的因素等进行了研究。  相似文献   

10.
基于Moldflow的注射成型与注压成型对比研究   总被引:1,自引:0,他引:1  
通过对注射成型和注压成型方法的Moldflow模拟仿真,结合两种成型方法的特点,对注射成型和注压成型方法生产超薄导光板的工艺条件和制品质量进行了详细的对比和分析。结果表明,注压成型制品所需的注射压力明显小于注射成型制品,注压成型可以节约能源;注压成型制品的残余应力和翘曲变形数值都小于注射成型的制品,注压成型能够增加制品生产的合格率,可以提高生产效率。  相似文献   

11.
Cycloaliphatic C21 di- and C22 tricarboxylic acids were prepared by the Diels-Alder reaction of dehydrated castor oil (DCO) fatty acids (containing 48% conjugated and 42% nonconjugated dienes) with acrylic and fumaric acids, respectively. The reaction temperature, time, catalyst concentration, and mole ratio of reactants were varied to get maximum yields of the di- and tricarboxylic acids. The unreacted DCO fatty acids were removed from the products by partition between aqueous methanol and n-hexane. The products were converted to methyl esters and characterized as the substituted cyclohexene derivatives before and after dehydrogenation with Pd/C in xylene, hydrogenation with Pd/C in decalin and oxidation with periodate-permanganate reagent and by mass and proton nuclear magnetic resonance spectrometry. The acids were converted to sodium soaps, mono- and diethanolamides and the corresponding diol and triol sulfates, and the resulting products were evaluated for their surface-active properties. The sodium soaps showed better calcium tolerance and poorer foaming power than sodium oleate. The diethanolamides were inferior to lauroyl diethanolamide in wetting and emulsifying power. The monoethanolamides were better than the respective diethanolamides and lauroyl diethanolamide in wetting property. The diol and triol sulfates were poorer in wetting and emulsifying ability and better in calcium tolerance than sodium lauryl sulfate.  相似文献   

12.
民用工业中复合材料桁架的应用和发展   总被引:1,自引:0,他引:1  
本文叙述了复合材料桁架的构造、分类和计算方法,突出了复合材料桁架的优越性能和在民用工业中的应用前景;在分析大量文献资料的基础上阐述复合材料桁架杆件的多种加工工艺,并比较不同截面形式对杆件性能的影响;探讨复合材料杆件的破坏机理和分析方法,介绍节点的类型和各自的特点,提出节点及连接部位存在的关键问题;根据国内外复合材料桁架的研究和应用现状,阐述了复合材料桁架的性能和不同的设计方法,总结归纳影响复合材料桁架性能的关键因素和设计中存在的一些问题,并提出改进杆件设计、节点设计和优化复合材料桁架的建议。  相似文献   

13.
熟料的岩相分析有助于熟料质量的判断及生产过程控制调整。根据多年实践经验,总结了手工和机械磨制岩相试样的方法及注意事项,并对几种熟料岩相特征(孔洞、游离氧化钙、A矿包裹B矿和f-Ca O、晶体尺寸不均和矿巢)进行了举例和形成原因分析。  相似文献   

14.
The scientific community and industrial companies have discovered significant enzyme applications to plant material. This rise imparts to changing consumers’ demands while searching for ‘clean label’ food products, boosting the immune system, uprising resistance to bacterial and fungal diseases, and climate change challenges. First, enzymes were used for enhancing production yield with mild and not hazardous applications. However, enzyme specificity, activity, plant origin and characteristics, ratio, and extraction conditions differ depending on the goal. As a result, researchers have gained interest in enzymes’ ability to cleave specific bonds of macroelements and release bioactive compounds by enhancing value and creating novel derivatives in plant extracts. The extract is enriched with reducing sugars, phenolic content, and peptides by disrupting lignocellulose and releasing compounds from the cell wall and cytosolic. Nonetheless, depolymerizing carbohydrates and using specific enzymes form and release various saccharides lengths. The latest studies show that oligosaccharides released and formed by enzymes have a high potential to be slowly digestible starches (SDS) and possibly be labeled as prebiotics. Additionally, they excel in new technological, organoleptic, and physicochemical properties. Released novel derivatives and phenolic compounds have a significant role in human and animal health and gut-microbiota interactions, affecting many metabolic pathways. The latest studies have contributed to enzyme-modified extracts and products used for functional, fermented products development and sustainable processes: in particular, nanocellulose, nanocrystals, nanoparticles green synthesis with drug delivery, wound healing, and antimicrobial properties. Even so, enzymes’ incorporation into processes has limitations and is regulated by national and international levels.  相似文献   

15.
The effects of extraction temperature and preservation method on the functional properties of soy protein isolate (SPI) were determined. Four extraction temperatures (25, 40, 60, and 80 °C) were used to produce SPI and yields of solids and protein contents were determined. Three preservation methods were also tested (spray-drying, freeze-drying, and freezing–thawing) and compared to fresh (undried) samples for each extraction temperature. No differences in yields of solids and protein were observed among SPIs extracted at 25, 40, and 60 °C; however, SPI extracted at 80 °C yielded significantly less solids and protein. Extraction temperature significantly affected SPI functionality. As extraction temperature increased, solubility and emulsification capacity decreased; surface hydrophobicities, emulsification activities and stabilities, and dynamic viscosities increased; and foaming properties improved. Preservation method also significantly affected SPI functionality. Drying method did not affect the denaturation enthalpies of SPIs, but spray-dried SPIs had higher solubilities, surface hydrophobicities, and emulsification stabilities, and lower viscosities, emulsification activities and rates of foaming than freeze-dried SPI exhibited. Emulsification and foaming capacities and foaming stabilities were similar for both methods of drying. There was significant interaction between extraction temperature and preservation method for all functional properties except emulsification capacity.  相似文献   

16.
The current year's growth of Douglas fir contains galactose, unusual in that this carbohydrate makes up 78.7% of the total carbohydrate fraction. An agar diet study was undertaken to determine the effects of galactose, other carbohydrates, and terpenes on western spruce budworm larval mortality, growth rate, and adult biomas production. All concentrations of the carbohydrates and terpenes tested, as well as other mineral elements not tested, were typical of the current year's foliage of Douglas fir. In experiment I, the diet containing 5.61% total carbohydrate did not significantly affect larval mortality when compared to the control diet. However, diets containing 9.45% and 15% total carbohydrate concentrations significantly increased larval mortality 64% and 96.1%, respectively, when compared to the control. Also in experiment I, terpenes alone (78.9% morality) and terpenes in combination with 9.45% and 15% total carbohydrates significantly increased larval mortality (97.2% and 100%, respectively) when compared to mortality on the control diet (44%). To determine which carbohydrate was causing the adverse effect, 6% glucose, 6% fructose, and 6% galactose were placed individually and in combination with terpenes in diets in experiment II. The 6% galactose diet significantly increased larval mortality and reduced growth rate when compared to the control, glucose, and fructose diets. Glucose resulted in 16% less larval mortality, significantly enhanced female larval growth rate and pupal weight, but did not affect male larval growth rate and pupal weight, when compared to the control. Fructose resulted in a significant decrease in larval mortality and a general trend of enhanced female and male larval growth rate and pupal weight. Larval mortality on terpenes alone was not significantly different from the control, but terpenes with 6% galactose increased larval mortality and decreased female and male growth rate and pupal weight significantly when compared to glucose-terpene and fructose-terpene diets. No significant interactions were found between carbohydrates and terpenes in either experiment.  相似文献   

17.
There is an increased demand for convenient foods including ready-to-eat and instant products. These products are desired with minimum concentration of synthetic chemicals. This creates challenges for the food industry and dryers manufactures to develop new technologies to process difficult-sensitive materials and to supply final products with high quality and improved properties. Fruits and vegetables are mainly composed of water, carbohydrates, proteins and lipids. Due to modification of chemical and physical bonds the compounds the material becomes viscous and sticky during processing. Conventional dryers have limitations in handling such sensitive materials. Heat pump dryers have been applied in the production of a diversity of ready-to-eat foods and dried instant products for the last five years at SINTEF-NTNU. Besides being energetically efficient and environmentally friendly, the heat pump drying technology provides a wide range of drying conditions as required to produce powders with improved characteristics. This work describes the new technologies and processing line for the production of instant foods as well as the measurements on the properties and quality attributes for raw, intermediate and final instant products.  相似文献   

18.
[目的]探讨毒死蜱和联苯菊酯在室内外土壤中的消解动态,并预测2种农药作为土壤化学屏障防治白蚁的有效期。[方法]采用气相色谱法测定不同时期土壤中毒死蜱和联苯菊酯的残留量并采用土壤穿透法测定2种农药在土壤中的生物活性。[结果]毒死蜱在室内和室外的半衰期分别为51.3、39.5 d,联苯菊酯在室内和室外的半衰期分别为31.3、44.5 d。毒死蜱和联苯菊酯抗白蚁穿透的最低有效质量分数分别为6.15、5.78 mg/kg,并结合消解动态方程预测出毒死蜱和联苯菊酯作为土壤化学屏障中有效成分的有效期在室内分别为195、29.1 d,在室外则分别为158.4、56.1 d。[结论]得到的白蚁防治有效期结果较好,为白蚁的化学防治提供理论依据。  相似文献   

19.
Technology and colour are viewed as interfaces between the environment, humans and human activity. Examples are provided of ways of facilitating and improving access to and use of colours by commercial users of colour coatings through improvements in the accuracy of measuring and displaying colour. By analogy, the task of providing effective interfaces within the coatings industry, between the coatings industry and the environment and between the coatings industry and the public and political domain are discussed. Examples of information shortfalls are cited to illustrate how distortions arise. Examples of more effective, integrated technological, organisational and political interfacing are culled from the author's experiences.  相似文献   

20.
1前言锆(Zirconium)的元素符号为Zr,位于元素周期表中第IV-B族元素,银白色金属。它具有熔点高、密度适中、良好的强度和塑性匹配,而且热中子吸收  相似文献   

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