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1.
化学品仓库集中存放着许多化工产品,这些产品性质复杂,多数有易爆、易燃、有毒、有腐蚀性的特点,扑救这类化学品的火灾是一项比较复杂的工作。如不能用水(包括水蒸气和含水的泡沫剂)扑救的化学品就有金属钠、钾、钙、镁、钍、铝粉、铝镁合金、氰化钠、硼氢化物、电石、磷化钙、发烟硫酸、氯磺酸、三氯化磷、五氯化二磷、无水氯化铝、过氧化钠、氯化硫酰、四氯化硅、五氨化锑、氯乙酰、苯基氯硅烷等忌水物质。  相似文献   

2.
赵罡 《中华手工》2018,(6):42-49
自然界,为人类提供了生存、生活,以及进行创造的物质基础。人们在自然界的劳动实践中,获取了竹、木、柳、藤、草、棉、革、漆、土、玉、石、陶、瓷、金、银、铜、铁、锡等成为生活用品的材料。随着造物活动的扩大,人们也创造了与这些材质相适应的雕、镂、刻、削、染、缝、绘、髹、铸、琢、磨等工艺。  相似文献   

3.
收集了2010年7月~2011年6月世界塑料工业的相关资料,介绍了2010~2011年世界塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚氯乙烯、聚苯乙烯、ABS树脂),工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚),特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮),通用热固性树脂(酚醛、不饱和聚酯树脂、环氧树脂、聚氨酯)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍。  相似文献   

4.
《化工机械》2015,(2):298
<正>非均相物系的分离是工业过程的基本单元过程,广泛应用在能源、资源、水资源、三废治理、气体净化、PM2.5的防治与降低、生物、材料、石化、化工、冶金、机械、电力、制药、中药现代化、食品、饮料、酒类、农产品加工、轻工、农副产品加工等各个领域。进入21世纪,世界能源匮乏、资源贫化、三废问题更加突出,对非均相分离技术的要求更高更复杂。当前科学技术的不断发展,特别是在生物化工、精细化工、新型材料等高新技术领域的迅速发展,促进了非均相分离技术的进步与提高。  相似文献   

5.
《玻璃》2014,(1)
正硅砂、砂岩、长石、白云石、石灰石等玻璃原料的实验室及半要业试验硅砂、砂岩、长石、白云石、石灰石等玻璃原料的采矿、选矿设计和工程总承包硅砂、砂岩、长石、白云石、石灰石矿的技术改造及技术咨询提供硅砂矿用专用各种型号的水力旋流器、分级机、受阻沉降器、擦洗机、螺旋溜槽砂岩矿专用各种型号的水力旋流器、分级机、受阻沉降器、湿式中磁磁洗机  相似文献   

6.
收集了2001年7月到2002年6月有关国外塑料工业的相关期刊资料,介绍了2001年到2002年国外塑料工业的发展情况,提供了世界各地域塑料原材料的产量及构成比,日本、美国、加拿大、德国、法国、比利时、墨西哥、芬兰、西班牙等国家的树脂产量、消费量及增长率,以及日本、西欧、北美等地区的不同品种塑料原料消费量和增长率统计.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)不同品种的顺序,对树脂的产量、消费量及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等有关技术作了详细的介绍.  相似文献   

7.
据报道,全球18种重要的化学品[乙烯、丙烯、聚乙烯、聚丙烯、甲醇、乙二醇、环氧乙烷、氨、苯酚、对苯二甲酸、对二甲苯、氯乙烯、丙烯晴、己内酰胺、苯乙烯、环氧丙烷、BTX(苯、甲苯、二甲苯)和异丙苯]生产所需能源占化工行业能源需求的80%。  相似文献   

8.
《玻璃》2012,(10):20
硅砂、砂岩、长石、白云石、石灰石等玻璃原料的实验室及半要业试验硅砂、砂岩、长石、白云石、石灰石等玻璃原料的采矿、选矿设计和工程总承包硅砂、砂岩、长石、白云石、石灰石矿的技术改造及技术咨询提供硅砂矿用专用各种型号的水力旋流器、分级机、受阻沉降器、擦洗机、螺旋溜槽  相似文献   

9.
《玻璃》2014,(3)
正硅砂、砂岩、长石、白云石、石灰石等玻璃原料的实验室及半要业试验●硅砂、砂岩、长石、白云石、石灰石等玻璃原料的采矿、选矿设计和工程总承包●硅砂、砂岩、长石、白云石、石灰石矿的技术改造及技术咨询●提供硅砂矿用专用各种型号的水力旋流器、分级机、受阻沉降器、擦洗机、螺旋溜槽●砂岩矿专用各种型号的水力旋流器、分级机、受阻沉降器、湿式中磁磁洗机  相似文献   

10.
《塑料工业》1997,25(3):67-90
收集了1995年7月到1996年6月国外塑料工业相关的期刊资料,介绍1995~1996年国外塑料工业进展。提供了美国、日本、德国、韩国、法国、荷兰、比利时、意大利等生产国及亚洲、西欧(包括全部欧洲联盟国家和奥地利、芬兰、挪威、瑞士和瑞典)、东欧、北美、中南美、非洲和大洋洲等地域的塑料材料产量,作为对比提供了中国台湾和外刊报导的中国塑料产量。按通用热塑性树脂(包括高密度聚乙烯、低密度聚乙烯、线型低密度聚乙烯、聚丙烯、聚苯乙烯、ABS和聚氯乙烯)、工程塑料(包括尼龙、聚碳酸酯、热塑性聚酯、聚甲醛和改性PPO/PPE)、通用热固性树脂(包括酚醛、聚氨酯、不饱和聚酯和环氧树脂)、特种工程塑料(包括聚苯硫醚、液晶聚合物、聚醚砜、聚醚醚酮、和聚芳酯)、有机硅树脂、有机氟树脂、丙烯酸树脂和降解塑料的顺序,对塑料材料产量、消费量和合成工艺、产品应用开发、树脂品种延伸等技术进展作了详尽介绍。  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.
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   

13.
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   

14.
15.
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   

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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