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排序方式: 共有204条查询结果,搜索用时 31 毫秒
21.
翁毓兰 《安全.健康和环境》2014,(6):21-23
介绍了热备用应急电源(EPS)的分类、原理、选型、特点以及操作注意事项。随着智能化程度的提高、快速切换型离线技术的应用,具有抗晃电、稳频稳压、离线运行、快速切换、等功率拖动电机特性的应急电源产品,已不仅仅局限于变电所、厂区照明的应用,而且还用于安全设备、生产设备等。 相似文献
22.
In this study,a series of polyetherimide/SBA-15: 2-D hexagonal P6 mm,Santa Barbara USA(PEI/SBA-15) adsorbents modified by phosphoric ester based surfactants(including tri(2-ethylhexyl)phosphate(TEP),bis(2-ethylhexyl) phosphate(BEP) and trimethyl phosphonoacetate(TMPA))were prepared for CO_2 adsorption.Experimental results indicated that the addition of TEP and BEP had positive effects on CO_2 adsorption capacity over PEI/SBA-15.In particular,the CO_2 adsorption amount could be improved by around 20% for 45PEI–5TEP/SBA-15 compared to the additive-free adsorbent.This could be attributed to the decrease of CO_2 diffusion resistance in the PEI bulk network due to the interactions between TEP and loaded PEI molecules,which was further confirmed by adsorption kinetics results.In addition,it was also found that the cyclic performance of the TEP-modified adsorbent was better than the surfactant-free one.This could be due to two main reasons,based on the results of in situ DRIFT and TG-DSC tests.First and more importantly,adsorbed CO_2 species could be desorbed more rapidly over TEP-modified adsorbent during the thermal desorption process.Furthermore,the enhanced thermal stability after TEP addition ensured lower degradation of amine groups during adsorption/desorption cycles. 相似文献
23.
随着资源的紧张和环境的恶化,发展现代循环农业对提高资源利用率和环境保护具有至关重要的意义。因此本文从低碳经济理论的内涵与发展、现代循环农业与主要技术对策、绿色农业视野三个层面的资源循环利用来综合分析如何发展现代农业。 相似文献
24.
A series of WO3/CeO2 (WOx/CeO2) catalysts were synthesized by wet impregnation of ammonium metatungstate on a CeO2 support. The resulting solid acid catalysts were characterized by X-ray diffraction (XRD), UV-Vis spectroscopy (UV-Vis), Raman spectroscopy (Raman), in-situ Fourier transform infrared spectroscopy (in-situ FT-IR) of ammonia adsorption, NH3-TPD, H2 temperature-programmed reduction (H2-TPR), NH3/NO oxidation and activity measurements for NOx reduction by NH3 (NH3-SCR). The results show that polytungstate (WOx) species are the main species of tungsten oxide on the surface of ceria. The addition of tungsten oxide enhances the Brönsted acidity of ceria catalysts remarkably and decreases the amount of surface oxygen on ceria, with strong interaction between CeO2 and WOx. As a result, the N2 selectivity of NH3 oxidation and NH3-SCR at high temperatures (> 300℃) is enhanced. Therefore, a wide working temperature window in which NOx conversion exceeds 80% (NOx conversion > 80%) from 200 to 450℃, is achieved over 10 wt.% WOx/CeO2 catalyst. A tentative model of the NH3-SCR reaction route on WOx/CeO2 catalysts is presented. 相似文献
25.
分析了我国钢铁企业环保工作现状,指出了节能环保工作中存在的主要问题,提出了“十五”后期节能环保工作的主要目标和对策。 相似文献
26.
单甲脒在水生生物中的积累和释放 总被引:1,自引:0,他引:1
本文朱生环境中对单甲脒在鱼和藻类中的积累释放及鱼体中的BCF值进行了研究,结果表明,鱼体在3,5,6d的BCF值分别为3.53,4.73及5.29,鱼体中单米积累为内脏〉锶〉肌肉,饲养7d达积累最高量;藻类在6h后达积累最高量;单甲脒在水藻和鱼(内脏)的富集比分别为1:3及1:12。 相似文献
27.
通过对水稻盆栽试验,应用15N示踪测试技术和土壤农业化学分析方法,研究接种不同剂量固氮芽孢菌对当季水稻的供氮能力,结果表明:在施有机肥的基础上,接种固氮芽孢杆菌能为当季水稻提供氮素,而且,接菌剂量在0.60亿个?pot-1以内,其供氮能力随着接菌剂量的增加而提高;接种剂量从0.15亿个?pot-1增加到0.60亿个?pot-1,其对当季初的氮素供应从88.7mg?pot-1提高至109.7mg?pot-1,并减少水稻对肥料氮和土壤氮的吸收,增加茬后土壤的速效氮积累,接种量以0.15亿个?pot-1~0.30亿个?pot-1较经济。但在一定的施肥基础上,接种固氮菌对水稻的产生量和吸收氮素总量影响不明显。 相似文献
28.
Pargol Ghavam Mostafavi Seyed Mohammad Reza Fatemi Mohammad Hassan Shahhosseiny Ove Hoegh-Guldberg William Kok Weng Loh 《Marine Biology》2007,153(1):25-34
Scleractinian coral species harbour communities of photosynthetic taxa of the genus Symbiodinium. As many as eight genetic clades (A, B, C, D, E, F, G and H) of Symbiodinium have been discovered using molecular biology. These clades may differ from each other in their physiology, and thus influence
the ecological distribution and resilience of their host corals to environmental stresses. Corals of the Persian Gulf are
normally subject to extreme environmental conditions including high salinity and seasonal variation in temperature. This study
is the first to use molecular techniques to identify the Symbiodinium of the Iranian coral reefs to the level of phylogenetic clades. Samples of eight coral species were collected at two different
depths from the eastern part of Kish Island in the northern Persian Gulf, and Larak Island in the Strait of Hormuz. Partial
28S nuclear ribosomal (nr) DNA of Symbiodinium (D1/D2 domains) were amplified by polymerase chain reaction (PCR). PCR products were analyzed using single stranded conformational
polymorphism and phylogenetic analyses of the LSU DNA sequences from a subset of the samples. The results showed that Symbiodinium populations were generally uniform among and within the populations of eight coral species studied, and there are at least
two clades of Symbiodinium from Kish and Larak islands. Clade D was detected from eight of the coral species while clade C was found in two of species
only (one species hosted two clades simultaneously). The dominance of clade D might be explained by high temperatures or the
extreme temperature variation, typical of the Persian Gulf.
Publication of this article was held up owing to technical problems. The publisher apologizes sincerely for this lengthy delay. 相似文献
29.
Chenghang Zheng Zhongyang Zhao Yishan Guo Haitao Zhao Weiguo Weng Weihang Zhu 《Journal of the Air & Waste Management Association (1995)》2020,70(7):708-720
ABSTRACT
Electrostatic precipitators (ESP) have been considered as the main particulate matter (PM) removal facility in the energy industry. This paper presents a real-time optimization method for a one-chamber industrial ESP in an ultra-low emission power plant with an intelligent optimization system (IOS). The IOS seeks to optimize the energy consumption of ESP subject to the outlet concentration requirement in real-time. A coordination control logic is designed to regulate the optimized operation set points with varying operation conditions. The operation optimized by the IOS is compared with the operations under PID (proportion-integral-derivative) and manual control. The results show that the IOS improves the emission compliance rate from 95% of manual control to 100% and the medium concentration is tuned to be 46.6% closer to the emission target. Furthermore, a good balance between emission and energy consumption is achieved, with 35.50% energy conservation for the same emission upper limit of 30 mg/m3. These results prove that the IOS significantly contributes to the efficient operation and economic PM removal by ESP for the energy industry. 相似文献
30.