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131.
正为确定泥炭泥浆中天然和人工同位素的含量,并估算标准泥炭泥浆处理过程中患者皮肤吸收的辐射剂量,分析了从波兰8个矿泉采集的37个样本,用γ能谱法测量同位素浓度活性。标准泥炭泥浆浴治疗中的皮肤剂量约为300 nSv,泥炭泥浆这种治疗的有效剂量被认为是22 nSv。治疗过程中 相似文献
132.
Gabriel Salierno Mauricio Maestri Stella Piovano Miryan Cassanello María Angélica Cardona Daniel Hojman Héctor Somacal 《中国化学工程学报》2018,26(6):1370-1382
Features of the motion of gel particles in a three-phase bubble column with non-foaming and foaming gas–liquid systems,determined by using experiments of radioactive particle tracking(RPT),have been compared.The tracer used is a gel particle which resembles typical immobilized biocatalyst.The tracer trajectory is analyzed to extract relevant information for design purposes.The solid velocity field,turbulence parameters,dispersion coefficients,mixing times and flow transitions are determined and compared.The presence of foam significantly affects many quantified parameters,especially within the heterogeneous flow regime.The hydrodynamic stresses are reduced in the presence of foam,especially close to the disengagement.The dispersion coefficients also decrease,and the solid mixing time is only slightly affected by the presence of foam.Gas holdup,inferred both from RPT experiments and from gamma ray scanning,is higher for foaming systems and leads to a shift in the transition gas velocity towards higher values. 相似文献
133.
本文以脂肪醇醚硫酸酯钠盐(SLES)和α-烯烃磺酸钠(AOS)两种阴离子表面活性剂所组成的二元餐洗剂配方为基础,通过引入两性离子[椰油酰胺丙基甜菜碱(CAB)]、非离子表面活性剂[椰油二乙醇酰胺(DEA)、脂肪醇聚氧乙烯醚(C_(12)–C_(15)–7EO,C_(10)–7EO和 C_9–C_(11)–7EO)、月桂基氧化胺(AO))对其进行配方改进。对比研究了6个餐洗剂配方(SLES/AOS、SLES/AOS/CAB/AO、SLES/AOS/DEA/AO,SLES/AOS/C_(12)-C_(15)-7EO/AO,SLES/AOS/C_(10)7EO/AO 和SLES/AOS/C_9–C_(11)–7EO/AO)的表面张力、临界胶束浓度(CMC)、清洗能力、发泡性、生物降解性和刺激性,以及温度的影响(17.0,23.0和42.0℃)。结果发现:相对于起始的二元配方,各种非离子表面活性剂的引入可以降低cmc和表面张力,提高餐洗剂配方的清洗能力和发泡性能,而对生物降解性和刺激性影响较小;相对于其他配方,配方6(SLES/AOS/C_9–C_(11)–7EO/AO)展现了最小的cmc和表面张力值,以及最佳的清洗效果;无论低温清洗(17℃)还是正常清洗(42℃),阴离子-非离子表面活性剂的餐洗剂配方(SLES/AOS/ethoxylated alcohols/AO)均具有明显的协同效应,展现出更好的应用性能。 相似文献
134.
Arcila-Lozano CC Loarca-Piña G Lecona-Uribe S González de Mejía E 《Archivos latinoamericanos de nutrición》2004,54(1):100-111
The oregano spice includes various plant species. The most common are the genus Origanum, native of Europe, and the Lippia, native of Mexico. Among the species of Origanum. their most important components are the limonene, gamma-cariofilene, rho-cymenene, canfor, linalol, alpha-pinene, carvacrol and thymol. In the genus Lippia, the same compounds can be found. The oregano composition depends on the specie, climate, altitude, time of recollection and the stage of growth. Some of the properties of this plant's extracts are being currently studied due to the growing interest for substituting synthetic additives commonly found in foods. Oregano has a good antioxidant capacity and also presents antimicrobial activity against pathogenic microorganisms like Salmonella typhimurium, Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, among others. These are all characteristics of interest for the food industry because they may enhance the safety and stability of foods. There are also some reports regarding the antimutagenic and anticarcinogenic effect of oregano; representing an alternative for the potential treatment and/or prevention of certain chronic ailments, like cancer. 相似文献
135.
R González J O García M A Barbés M J Quintana L F Verdeja J I Verdeja 《钢铁研究学报(英文版)》2010,17(10):50-56
This research shows, through the analysis of three steels that comply with the EN 10149-2 Euronorm, examples of ultrafine grained (or ultrafine ferrite) ferrous alloys, with ASTM grain sizes close to 14 (2 3 m). These steels are microalloyed with Ti-Nb and have been produced by advanced hot rolling controlled techniques in the factories of ArcelorMittal de Avilés (Asturias, Spain) and are mostly used in automotive and construction applications. By comparison, other techniques to obtain ultrafine grained steels are mentioned, though they have not yet reached the industrial level and are produced in laboratories due to the fact that their mechanical properties (low strain hardening coefficient n) don't allow cold working operations such as bending, stretching nor drawing. 相似文献
136.
有人说,用PPT做课件不够绚,我说不,比如PPT2007里就有非常多的三维图形,配上动画,效果绝对震撼!对,无需动用3DMax,直接用PPT完成。5秒钟制作三维图形在2007中我们可以对所有插入的素材做三维效果(以形状为例)。先介绍一个简单的方法:进入"插入→形状", 相似文献
137.
China Petrochemical Corporation 《中国油气》2008,15(1):12-15
China Petrochemical Corporation (Sinopec), a leading oil refiner, posted a net profit of 70 billion yuan (9.63 billion U.S. dollars) in 2007. Sinopec made a net profit of 50.66 billion yuan in 2006. The huge profit can be attributed to cost control, resources integration and technological innovation, according to Cai Xiyou, a senior executive of Sinopec. 相似文献
138.
The scientific technological development of CNOOC Limited entered a new stage during the Tenth Five-Year Plan period. High-tech researches in the company have catalyzed the technological innovation of the offshore petroleum industry.…… 《中国油气》2007,14(1):28-33
The scientific and technological development of CNOOC Limited entered a new stage during the Tenth Five-Year Plan period. High-tech researches in the company have catalyzed the technological innovation of the offshore petroleum industry. By undertaking 11 key projects concerning key technologies for exploration and development of giant Bohai oil field under China's National 863 Program, 24 sub-projects of CNOOC's projects matching with China's National 863 Program, and 10 sub-projects of National Key S & T Special Projects through cooperation with Chinese Academy of Sciences, the company developed 10 technology series with intellectual property rights. 相似文献
139.
Chinese petrochemical companies should gird for new challenges in three years triggered by cost-competitive products flooding in from overseas especially the Middle East countries.This advice was highlighted by company executives association leaders during a discussion on the sidelines of a petrochemical conference organized by the China Petroleum Chemical Industry Association in early April.…… 《中国油气》2007,14(2):21-21
Chinese petrochemical companies should gird for new challenges in three years, triggered by cost-competitive products flooding in from overseas, especially the Middle East countries. This advice was highlighted by company executives and association leaders during a discussion on the sidelines of a petrochemical conference organized by the China Petroleum and Chemical Industry Association in early April.[第一段] 相似文献
140.
The great urban and industrial development of the towns surrounding Madrid has caused an irreversible and rapid soil loss. In this paper, soil sealed evolution in Guadalajara province during the past 15 years, mainly in the capital, industrial district and small municipalities near Madrid, has been studied. This province has experimented a sharp reduction of the most fertile soils, located on the Henares valley, due to the action of new models of local and regional development. The main goal of this paper is the mapping of the covered soils in a pilot area of Spain. Supervised classification of Landsat images from 1989 to 2002 has been carried out. Geo-referred image analysis allows us to detect precisely the amount of covered soils and where this phenomenon has taken place. 相似文献