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1.
ISO正式标准TC31轮胎、轮辋和气门嘴ISO4250-1:2006工程机械用轮胎和轮辋第1部分:轮胎规格代号和尺寸ISO4250-2:2006工程机械用轮胎和轮辋第2部分:负荷和充气压力ISO4250-3:2006工程机械用轮胎和轮辋第3部分:轮辋ISO4251-3:2006拖拉机和农业机械用轮胎和轮辋(层级标志系列)第3部分:轮辋TC35色漆和清漆ISO150:2006色漆和清漆用生亚麻子油、精亚麻子油和熟亚麻子油规格和试验方法ISO1248:2006氧化铁颜料规格和试验方法ISO4618:2006色漆和清漆符号和定义TC45橡胶和橡胶制品ISO247:2006橡胶灰分的测定ISO1307:2006橡胶和塑料软管…  相似文献   

2.
熏燕剂和杀线虫剂:概述;熏蒸剂和杀线虫剂:产品来源、原材料和环境问题;熏蒸剂和杀线虫剂:美国的供应和需求;熏蒸剂和杀线虫剂:西欧的供应和需求;熏蒸剂和杀线虫剂:日本的供应和需求 ;染料:概述;染料:生产方法;……  相似文献   

3.
炸药和爆炸剂:前言(英文),炸药和爆炸剂:北美供应和需求(英文),炸药和爆炸剂:拉美供应和需求(英文),炸药和爆炸剂:西欧供应和需求(英文),炸药和爆炸剂:中欧/东欧供应和需求(英文)  相似文献   

4.
塑料管材和板材的挤出成型   总被引:3,自引:0,他引:3  
从原料、设备、工艺等方面介绍塑料管材和板材挤出成型的基本原理和方法。重点介绍管材和板材的种类、主要应用领域和范围;挤出设备的组成和特点,管材机头和板材机头的工艺要求和结构特点,冷却定型和定径的方法,列举了几种常见的管材冷却方式,给出了常见塑料管材和板材的参考加工温度。并对特殊性能和结构的管材挤出和板材挤出进行了简单介绍。  相似文献   

5.
许炳才 《橡胶工业》2007,54(1):40-40
为了表彰在推动石油和化学工业科技进步、促进经济和社会发展中做出贡献的单位和个人,进一步激励和调动广大科技工作者的积极性和创造性,提高科技进步水平,促进科技与经济紧密结合,根据“中国石油和化学工业协会科学技术奖励办法”,经中国石油和化学工业协会科技奖励评审委员会函审、专业评审和终审,并在新闻媒体和网站公示征求意见后,中国石油和化学工业协会公布了2006年度中国石油和化学工业协会科学技术奖获奖项目。  相似文献   

6.
建立一种用气相色谱同时测定联苯菊酯和三唑磷的分析方法。使用带氢火焰离子化检测器的气相色谱仪和毛细管柱,对试样中的联苯菊酯和三唑磷进行气相色谱分离和测定。联苯菊酯和三唑磷的标准偏差分别为0.083和0.11,变异系数为2.63%和0.64%,平均添加回收率为99.05%和99.65%,线性相关系数分别为0.997 7和0.998 4。该方法分析时间短,精密度和准确度均符合定量分析的要求。  相似文献   

7.
人造草地和人工渔礁,电池外壳及桥墩,地毯底衬和建筑用包,排水过滤器,河堤,地砖,垫圈,港口和码头,绝缘和工业涂料,牲畜棚地垫和垃圾填埋工程,田径球类运动场地和家具,屋顶材料和路面,鞋底和坚实的车轮,隔音屏障和防振垫。如此多样化的应用和产品之间有什么共同之处?一句话,它们都是用废旧轮胎再生材料为原材料生产出来的。  相似文献   

8.
企业发展战略,就是在内外环境变化和竞争激烈的市场经济条件下,对企业发展宗旨和使命、企业的经营领域和发展目标,以及实现发展目标的保障措施等所作出的具有全局性、根本性和长远性的谋划和对策。企业发展战略研究的主要内容有:企业的宗旨和使命、经营领域和发展目标、保障措施和进行调整。企业发展的宗旨和使命是指企业创办和发展的终极目的和追求,企业承担的社会责任和义务。它是企业的社会价值观和社会伦理的体现和反映。企业是社会的器官,是创造财富的经济组织,它是为推进社会经济发展而存在的。一个没有社会责任感和使命感的企…  相似文献   

9.
控释和缓释肥的研究现状与进展   总被引:106,自引:6,他引:106  
张民  史衍玺  杨守祥  杨越超 《化肥工业》2001,28(5):27-30,63
对控释和缓释肥的概念和分类,制作方法和作用机理,控释机制与概念模型,实际应用与评价等方面进行了综述,分析了我国控释和缓释肥研制的现状和进展,指出了进一步研究和开发应注意的问题和方向。  相似文献   

10.
从原料、设备、工艺等方面介绍塑料管材和板材挤出成型的基本原理和方法。重点介绍管材和板材的种类,主要应用领域和范围;挤出设备的组成和特点,管材机头和板材办头的工艺要求和结构特点,冷却定型和定径的方法,列举了几种常见的管材冷却方法,给出了常见塑料管材和板材的参考加工温度。并对特殊性能和结构的管材挤出和板材挤出进行了简单介绍。  相似文献   

11.
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   

12.
Abiotic stresses, such as drought, salinity, heat, cold, and heavy metals, are associated with global climate change and hamper plant growth and development, affecting crop yields and quality. However, the negative effects of abiotic stresses can be mitigated through exogenous treatments using small biomolecules. For example, the foliar application of melatonin provides the following: it protects the photosynthetic apparatus; it increases the antioxidant defenses, osmoprotectant, and soluble sugar levels; it prevents tissue damage and reduces electrolyte leakage; it improves reactive oxygen species (ROS) scavenging; and it increases biomass, maintains the redox and ion homeostasis, and improves gaseous exchange. Glutathione spray upregulates the glyoxalase system, reduces methylglyoxal (MG) toxicity and oxidative stress, decreases hydrogen peroxide and malondialdehyde accumulation, improves the defense mechanisms, tissue repairs, and nitrogen fixation, and upregulates the phytochelatins. The exogenous application of proline enhances growth and other physiological characteristics, upregulates osmoprotection, protects the integrity of the plasma lemma, reduces lipid peroxidation, increases photosynthetic pigments, phenolic acids, flavonoids, and amino acids, and enhances stress tolerance, carbon fixation, and leaf nitrogen content. The foliar application of glycine betaine improves growth, upregulates osmoprotection and osmoregulation, increases relative water content, net photosynthetic rate, and catalase activity, decreases photorespiration, ion leakage, and lipid peroxidation, protects the oxygen-evolving complex, and prevents chlorosis. Chemical priming has various important advantages over transgenic technology as it is typically more affordable for farmers and safe for plants, people, and animals, while being considered environmentally acceptable. Chemical priming helps to improve the quality and quantity of the yield. This review summarizes and discusses how exogenous melatonin, glutathione, proline, and glycine betaine can help crops combat abiotic stresses.  相似文献   

13.
以中低温煤焦油轻油和重油为实验原料,采用常压蒸馏获得170~200℃、200~240℃、240~270℃、270~300℃、300~320℃、320~340℃、340~360℃和360~390℃煤焦油馏分油;利用配有油品加氧制冷进样系统的ICP-OES测定了21种微量元素在馏分油中的含量,考察了不同馏分油中元素的分布情况。研究表明:在原煤焦油中,未发现Ag、Mg、Mo、Na、Ni、Fe、Mn、Cr及Ti元素,含量较高的元素有Sn、P、Al、Pb、Si,其中Sn元素在轻油和重油中的含量分别为11.78μg/g和14.04μg/g;在所有馏分油中,未发现Al、Mo、Fe、Mn、Cr及Ti元素,含量比较高的元素有Si、Sn、Na、Zn、Pb,特别是Si、Na、Sn、Zn、Ni、Pb及B元素可以有效富集于馏分油中。可能的原因是Ca、Fe、Mg、Al等金属以不同的盐类形态存在,在煤焦油脱水及<170℃蒸馏过程中,这些金属盐类会被部分带出,导致其在馏分油中的含量未富集或未检出;通过关联金属元素在馏分油中的分布与其组成的关系,馏分油中元素的分布可能与酚类化合物、杂环化合物和蒸馏温度等相关。酚类化合物及杂环化合物可能与Ag、B、Cu、Mo、Sn、Na、Zn、Ca、Pb等金属形成络合物或卟啉配合物,蒸馏温度一方面可以破坏Sn、Cd、Pb、Zn、Cu、Ca、Pb等元素在馏分油中的结合力,另一方面也可以促进这些元素与馏分油中的含氧、含氮等化合物更好地发生化合反应,进而影响金属元素在馏分油中的含量分布。  相似文献   

14.
Anaphylaxis is a severe, acute, life-threatening multisystem allergic reaction resulting from the release of a plethora of mediators from mast cells culminating in serious respiratory, cardiovascular and mucocutaneous manifestations that can be fatal. Medications, foods, latex, exercise, hormones (progesterone), and clonal mast cell disorders may be responsible. More recently, novel syndromes such as delayed reactions to red meat and hereditary alpha tryptasemia have been described. Anaphylaxis manifests as sudden onset urticaria, pruritus, flushing, erythema, angioedema (lips, tongue, airways, periphery), myocardial dysfunction (hypovolemia, distributive or mixed shock and arrhythmias), rhinitis, wheezing and stridor. Vomiting, diarrhea, scrotal edema, uterine cramps, vaginal bleeding, urinary incontinence, dizziness, seizures, confusion, and syncope may occur. The traditional (or classical) pathway is mediated via T cells, Th2 cytokines (such as IL-4 and 5), B cell production of IgE and subsequent crosslinking of the high affinity IgE receptor (FcεRI) on mast cells and basophils by IgE-antigen complexes, culminating in mast cell and basophil degranulation. Degranulation results in the release of preformed mediators (histamine, heparin, tryptase, chymase, carboxypeptidase, cathepsin G and tumor necrosis factor alpha (TNF-α), and of de novo synthesized ones such as lipid mediators (cysteinyl leukotrienes), platelet activating factor (PAF), cytokines and growth factors such as vascular endothelial growth factor (VEGF). Of these, histamine, tryptase, cathepsin G, TNF-α, LTC4, PAF and VEGF can increase vascular permeability. Recent data suggest that mast cell-derived histamine and PAF can activate nitric oxide production from endothelium and set into motion a signaling cascade that leads to dilatation of blood vessels and dysfunction of the endothelial barrier. The latter, characterized by the opening of adherens junctions, leads to increased capillary permeability and fluid extravasation. These changes contribute to airway edema, hypovolemia, and distributive shock, with potentially fatal consequences. In this review, besides mechanisms (endotypes) underlying IgE-mediated anaphylaxis, we also provide a brief overview of IgG-, complement-, contact system-, cytokine- and mast cell-mediated reactions that can result in phenotypes resembling IgE-mediated anaphylaxis. Such classifications can lead the way to precision medicine approaches to the management of this complex disease.  相似文献   

15.
16.
This article summarizes and reviews the various preparation methods, physical properties, and potential applications of one-dimensional nanostructures of conjugated polyaniline (PANI), polypyrrole (PPY) and poly(3,4-ethylenedioxythiophene) (PEDOT). The synthesis approaches include hard physical template method, soft chemical template method, electrospinning, and lithography techniques. Particularly, the electronic transport (e.g., electrical conductivity, current-voltage (I-V) characteristics, magnetoresistance, and nanocontact resistance) and mechanical properties of individual nanowires/tubes, and specific heat capacity, magnetic susceptibility, and optical properties of the polymer nanostructures are presented with emphasis on size-dependent behaviors. Several potential applications and corresponding challenges of these nanofibers and nanotubes in chemical, optical and bio-sensors, nano-diodes, field effect transistors, field emission and electrochromic displays, super-capacitors and energy storage, actuators, drug delivery, neural interfaces, and protein purification are also discussed.  相似文献   

17.
松香是一类产量丰富、价格低廉的可再生林产资源,被广泛地应用于食品、农业、橡胶、油墨、涂料等领域。松香的三环二萜结构具有超强的疏水性,通过催化异构、Diels-Alder加成等手段引入亲水基团可制备高附加值、易生物降解的绿色表面活性剂。本文从阴离子、阳离子、非离子和两性离子表面活性剂4个大类对松香基表面活性剂应用的文献及专利进行综述,重点分析了羧酸盐、磺酸盐、硫酸盐和磷酸盐4种阴离子型表面活性剂和季铵盐阳离子型表面活性剂,多元醇型和聚氧乙烯型非离子表面活性剂,以及甜菜碱型和氧化胺型两性离子表面活性剂。剖析松香基表面活性剂产业化开发的新技术及新产品概况,提出松香基表面活性剂替代传统表面活性剂的潜在应用领域。同时,对松香基表面活性剂的研究发展与产业化发展进行了评价与展望。  相似文献   

18.
Separation and purification techniques are applied in many important fields, such as in the medical, chemical, metallurgical, environmental, and pharmaceutical industries. Recent advances in separation science and the urgent need for highly selective purification have necessitated a rapid progress with respect to the reagents, chemicals, and surfactants used in separation processes to attain a high efficiency and selectivity. Polymeric materials have attracted considerable interest, and they have been widely used as extractants, catalysts, and modifiers, in separation and purification processes. This review outlines the recent advances in the use of novel polymers, natural and synthetic, in different separation and purification techniques. Various separation techniques such as chromatography, crystallization, precipitation, distillation, electrophoresis, filtration, and mineral processing methods are discussed, and the polymers used in each method are described in terms of their properties, structure, and function. The application of polymers shows great promise in achieving a highly efficient separation, especially in the areas of membrane separation and water purification. The rational design of new multifunctional polymers with triggered functions presumably presents new opportunities for the development of advanced separation methods.  相似文献   

19.
Shifeng Dai  Dexin Han 《Fuel》2006,85(4):456-464
Coals from Luquan, Yunnan Province, China, have high contents of cutinite and microsporinite, with an average of 55 and 33.5 vol%, respectively, (on a mineral-free basis). The coals are classified as cutinitic liptobiolith, sporinite-rich durain, cutinite-rich durain, and sporinitic liptobiolith. These four liptinite-rich coals are often interlayered within the coal bed section and vary transversely within the coal bed. The vitrinite content varies from as low as 1.6-20.5% (mineral-free basis), and it is dominated by collodetrinite, collotelinite, and corpogelinite. The maceral composition may be attributed to the type of the peat-forming plant communities. Moreover, the Luquan coals are characterized by high contents of volatile matter, hydrogen, and oxygen, and the high values of the atomic hydrogen to carbon ratio as a result of the maceral composition. As compared with the common Chinese coals and the upper continental crust, the Luquan coals are enriched in Li, B, Cu, Ga, Se, Rb, Mo, Ba, Pb, Bi, and U, with averages of 99.9, 250, 111, 24.4, 4.55, 130, 58.8, 1276, 162, 3.85, and 34.1 μg/g, respectively. The SEM-EDX results show that V, Cr, Ga, and Rb occur mainly in clay minerals, and Cu and Pb are associated with clay minerals and pyrite, and Mo and U are mainly in clay minerals and organic matter. Barite and clay minerals are the main carrier of barium. The high B and U contents are probably resulted from deep seawater influence during coal formation.  相似文献   

20.
Since the earliest discovery and subsequent developments in the world of polymers associated problems and increasing applications have resulted in the rapidly expanding field of “additives.” In this context, the term additive is very generalized in that it encompasses many facets associated with ever growing needs. Of the most important are antioxidants (primary and secondary), light stabilizers, processing aids, metal deactivators, flame retardants, biocides, nucleating agents, antistatic compounds, fillers, dyes, pigments (nano, micro, and macro) to name but only a few each serving a particular function and not necessarily all at the same time in the one package. This article presents a general perspective on the type, mode of action, properties, uses, and problems (and circumvention) based on some of the more important key additives. The properties and behavior of many additives in this regard relates very much to the initial incorporation and formulation and in turn is often a major controlling factor in end use performance from a physical, esthetic, structural, mechanical, and chemical point of view. Indeed, with many polymers like PVC, for example, one enters a highly complex world of interactions which can in many cases destroy or even enhance the activity of functional processing additives. Some of these will be highlighted and hopefully the aim being here to enthuse the polymer and additive manufacturers and technologists in the processing laboratories to become more aware of potential issues and problems.  相似文献   

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