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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.
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   

3.
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   

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.
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   

7.
《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   

8.
《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   

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.
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   

11.
Yongxi Cui  Masao Iwamori 《Lipids》1997,32(6):599-604
Cholesterol sulfate (CS) recently has been shown to be involved in signal transduction pathway. To evaluate its functional significance, we determined the concentration of CS, and the specific activities of cholesterol sulfotransferase and CS sulfatase in various tissues of rabbit, and compared them with the concentration of sulfoglycolipids in rabbit tissues. CS was present in the epithelia and mucosa, but not in the tunica muscularis, of the digestive tract, trachea, uterine endometrium and uterine cervix. It was also present in lung, spleen, kidney, prostate, skin, hair, and nail at relatively high concentrations. Its concentration in the uterine endometrium was nine times higher in pseudopregnant rabbits than in nonpregnant rabbits because of activation of cholesterol sulfotransferase and inhibition of CS sulfatase in the pseudopregnant rabbits. Sulfoglycolipids were not detected in the uterine endometria of either nonpregnant-or pseudopregnant rabbits. However, sulfoglycolipids were detected at relatively high concentrations in the cerebrum, cerebellum, stomach, duodenum, jejunum, testis, and kidney of rabbits and thus the tissues in which both sulfolipids were detected were the gastrointestinal tract and kidney. In the digestive tract, the concentration of CS decreased in the order esophagus, stomach, duodenum, and jejunum, but that of sulfatide increased in the same order, indicating distribution of CS in the squamous epithelium. In addition, both CS and sulfatide were detected in the serum. On the other hand, CS sulfatase activity was detected in all tissues examined, even in hair, from which the enzyme was liberated by brief sonication, and its highest specific activity was deteted in the liver. The specific activity of cholesterol sulfotransferase varied among the tissues examined and was found to be significantly high in the esophageal epithelium and the uterine endometrium of pseudopregnant rabbit, indicating involvement of cholesterol sulfation in the formation of epithelium.  相似文献   

12.
黄樟素植物资源的开发利用现状及前景   总被引:4,自引:0,他引:4  
本文探讨了黄樟素植物资源的种类、分布、各部位器官精油和黄樟素含量 ,及其开发利用现状及前景。据统计 ,精油中含黄樟素的植物共有 62种 ,其中精油含量较高 ( >4 0 % )的有 3 2种。在这 3 2种植物中 ,在根和 (或 )茎精油中主要成分为黄樟素的植物有 2 0种 ;在皮油中的有 4种 ;叶油中的 1 0种 ;果实和种子中的 6种 ;有 4种是草本 ,全草精油主要成分为黄樟素。樟科植物是黄樟素的重要植物资源 ,共有 3 7种樟科植物含有黄樟素 ,有 2 4种樟科植物黄樟素含量较高 ( >4 0 % )。狭叶桂 (C .angustifoliaB .Q .Cheng)、少花桂 (C .paciflorum )、等植物叶、茎、枝、皮和果的精油中 ,岩桂 (C .petrophilumN .Chao)、香樟 (C .camphora)、毛叶树胡椒 (Piperhispidinervium)等的叶精油中黄樟素含量均较高 ,这些植物可作为持续发展生产黄樟素的理想资源。其中从巴西引种的毛叶树胡椒是投产最快、具有较大开发前景的黄樟素新资源。本文旨在为黄樟素植物资源的开发利用及保护提供理论依据。  相似文献   

13.
Mean intakes of dietary fiber (DF) were estimated in the population of Central America and Panama, using the results of dietary surveys conducted in 1969 and 1986 both in rural and urban areas, as well as data on the DF content of foods as consumed in the region. Data on preschool children were also estimated. The results indicated that DF intake in urban areas is lower than that of rural areas, particularly in Costa Rica and Panama. In 1969, intake varied from 32g in El Salvador to 15g in Panama in urban areas, while in rural areas intake was from 45g in El Salvador to 13g in Panama. The foods which contributed most to the total intake in Guatemala, El Salvador and Honduras were tortillas and beans, while in Costa Rica and Panama, beans provided the largest intake. In preeschool children, intake was 12.5g in El Salvador and 5.4g in Costa Rica in 1969, which is the same tendency as that found for adults. From more recent data on food intake, it was found that DF intake had decreased in the rural areas of El Salvador, Honduras and Costa Rica, being between 4 and 9% in the first two countries and 12% in Costa Rica. In the urban area of the latter, from 1969 to 1986 a decrease in DF intake of around 20% has taken place.  相似文献   

14.
为探讨泰乐菌素在提取工艺中溶液中的稳定性,取提取工艺中不同环节的泰乐菌素溶液,采用高效液相色谱法测定在一定时间内检测泰乐菌素的含量,观察不同环节的泰乐菌素溶液的降解情况。结果显示,在提取工艺中不同环节的泰乐菌素溶液,均较稳定,结果证明,提取工艺中不同环节的泰乐菌素溶液稳定,基本上不降解。  相似文献   

15.
RNA binding protein with multiple splicing (RBPMS) is expressed exclusively in retinal ganglion cells (RGCs) in the retina and can label all RGCs in normal retinas of mice, rats, guinea pigs, rabbits, cats, and monkeys, but its function in these cells is not known. As a result of the limited knowledge regarding RBPMS, we analyzed the expression of RBPMS in the retina of different mammalian species (humans, pigs, and rats), in various stages of development (neonatal and adult) and with different levels of injury (control, hypoxia, and organotypic culture or explants). In control conditions, RBPMS was localized in the RGCs somas in the ganglion cell layer, whereas in hypoxic conditions, it was localized in the RGCs dendrites in the inner plexiform layer. Such differential distributions of RBPMS occurred in all analyzed species, and in adult and neonatal retinas. Furthermore, we demonstrate RBPMS localization in the degenerating RGCs axons in the nerve fiber layer of retinal explants. This is the first evidence regarding the possible transport of RBPMS in response to physiological damage in a mammalian retina. Therefore, RBPMS should be further investigated in relation to its role in axonal and dendritic degeneration.  相似文献   

16.
With the objective to establish the cause-effect relationship between a geological area and the iodine content in cattle milk, and to estimate the contribution of milk consumption to the dietary iodine intake, the iodine content in cattle milk from the sierra and the coastal regions of Perú was determined. Milk samples were collected of cows from the three main productive zones of Perú, 62 in Cajamarca, 42 in Arequipa, both in the sierra, and 27 in Lima at the coast. The measurement of iodine was made by the method of Zak, based on the Sandell- Kolthoff reaction. The median values obtained were 24 microg/L in Cajamarca, 34 microg/L in Arequipa, and 170 microg/L in Lima. The median value in the sierra, 26 microg/L, was significantly lower than the one found in the coast. Moreover, while in the former 81% of individual values were below 50 microg/L, in the latter, on the contrary, 77% were above 80 microg/L. These results confirm that the iodine content in cattle milk is related to ecological factors. At the same time, they demonstrate that the iodine content in milk from the sierra is six times lower than in milk from the coast, and also that its consumption does not contribute significantly to satisfy the human physiological requirements of iodine in that zone.  相似文献   

17.
18.
Endometrial cancer (EC) is the fourth most common cancer in women in developed countries. Although it is usually diagnosed in postmenopausal women, its incidence has increased in young women, as well in recent decades, with an estimated rate of 4% in those under 40 years of age. Factors involved in this increase, particularly in resource-rich countries, include delayed childbearing and the rise in obesity. The new molecular classification of EC should help to personalize treatment, through appropriate candidate selection. With the currently available evidence, the use of oral progestin either alone or in combination with other drugs such as metformin, levonorgestrel-releasing intrauterine devices and hysteroscopic resection, seems to be feasible and safe in women with early-stage EC limited to the endometrium. However, there is a lack of high-quality evidence of the efficacy and safety of conservative management in EC. Randomized clinical trials in younger women and obese patients are currently underway.  相似文献   

19.
王彦  左宁  姜媛媛  陈芳媛 《化工进展》2020,39(4):1539-1549
污泥生物炭中氮硫元素含量高,其氮硫行为和环境效应对全球气候变化的影响不容忽视。以往的研究中,研究者往往以富碳生物炭作为主要研究对象,关注碳对全球气候变化的行为和功效,而对氮硫元素的作用关注不够。本文从原始污泥基本性质到其热解过程,再到生物炭的老化,逐步对污泥生物炭整个生命周期内氮硫的行为及其环境效应研究进行综述,并对未来应注重开展的研究方向进行展望,为生物炭中氮硫元素固定、释放及与之关联的环境效应和温室气体排放控制研究提供理论基础。分析表明,污泥中氮元素含量普遍高于硫元素,且热解过程中氮比硫更容易转移至气相产物。氮硫元素随热解温度的增加,在三相产物中的分配都是炭中持续减少,油中先增后减,气中一直增加。高温(>800℃)条件下,气相中的氮含量高于固相,而硫元素则仍然主要存在于固相中。污泥生物炭老化及其环境效应研究表明,污泥生物炭氮硫元素与土壤的相互作用及其温室效应问题在今后的研究中应引起重视。  相似文献   

20.
This paper, a review of the state of the art of the drying process in wet porous media, presents an overview of thermodynamic relations in heat treatment of synthetic fiber fabrics. Heat and mass transfer in wet porous media are coupled in a very complicated way. The structure of the solid matrix varies widely in shape. There is, in general, a distribution of void sizes, and the structures may be locally irregular. Energy transport in such a medium occurs by conduction in all of the phases. Mass transport occurs within voids of the medium. In an unsaturated state, these voids are partially filled with a liquid, whereas the rest of the voids contain some gas. It is a common misapprehension that nonhygroscopic fibers (i.e., those with intrinsically low moisture content) will automatically produce a hydrophobic fabric. The main significance of the fine geometry of a textile structure in contributing to resistance to water penetration can be stated in a different manner. Published in Russian in Teoreticheskie Osnovy Khimicheskoi Tekhnologii, 2006, Vol. 40, No. 1, pp. 17–30. This article was submitted by the author in English.  相似文献   

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