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21.
《安全生产许可证条例》依法确立了针对矿山企业的一项安全生产许可证制度,规定矿山企业必须依法取得安全生产许可证之后方可从事生产活动.安全生产许可证的颁发和管理是安全监管工作的一项新内容和重要的手段,是安监部门的项重要工作.我区非煤矿山数量大,基础条件差,安全生产许可证的颁发和管理工作更要周密组织,规范运作,严格依法办事.《安全生产许可证条例》颁布以后,国家安全生产监督管理局又先后出台了《非煤矿山企业安全生产许可证实施办法》及若干问题的说明和审核颁发工作有关问题的说明,对安全生产许可证审核颁发工作作了具体安排.我区在贯彻执行国家有关规定过程中应注意如下问题. 相似文献
22.
往复式低温液氧泵(简称液氧泵),是用来抽送制氧机生产的低温液氧并提高其压力的机械。制氧机生产的低温液氧经液氧泵升压,再经气化复热升温后充入气瓶。采用这种方法充氧比用气化器充氧操作简便,液氧利用率高,还可回收液氧的冷量,使产品的能耗下降。故此,在空分设备中,越来越多地用液氧泵来替代氧气压缩机。 相似文献
23.
Diazinon [O,O-diethyl O-2-isopropyl-6-methyl(pyrimidine-4-yl) phosphorothioate] and imidacloprid [1-(1-[6-chloro-3-pyridinyl]methyl)-N-nitro-2-imidazolidinimine] are applied to lawns for insect control simultaneously with nitrogenous fertilizers such as urea, but their potential effect on urease activity and nitrogen availability in turfgrass management has not been evaluated. Urease activity in enzyme assays, washed cell assays, and soil slurries was examined as a function of insecticide concentration. Intact cores from field sites were used to assess the effect of insecticide application on urease activity in creeping bentgrass (Agrostis palustris Huds.) and bluegrass (Poa pratensis L.) sod. Bacterial urease from Bacillus pasteurii and plant urease from jack bean [Canavalia ensiformis (L.) DC.] were unaffected by the insecticides. Both insecticides inhibited the growth of Proteus vulgaris, a urease-producing bacterium, but only diazinon significantly reduced urease activity in washed cells; neither insecticide inhibited urease activity in sonicated cells. Neither diazinon nor imidacloprid inhibited urease activity in Woolper soil (fine, mixed, mesic Typic Argiudoll) slurries, but diazinon slightly inhibited urease activity in Maury soil (fine, mixed, semiactive, mesic Typic Paleudalf) slurries. Imidacloprid had no effect on urease activity in creeping bentgrass or bluegrass sod at up to 10 times the commercial application rate. Diazinon briefly, but significantly, reduced urease activity in bluegrass sod. Co-application of imidacloprid and urea appears to be benign with respect to urease activity in soil and sod. Diazinon, in contrast, appears to have a significant, short-term, inhibitory effect on the microbial urease-producing community, but that effect depends on soil type. 相似文献
24.
自治区应急管理厅6月4日公布今年第二批安全生产失信联合惩戒单位名单,将茂名建筑集团第一有限公司等7家生产经营单位及其有关人员纳入安全生产失信联合惩戒管理。这7家公司分别是:茂名建筑集团第一有限公司、广西河池运达汽车运输有限责任公司宜州汽车总站、苍梧县沙头镇连发多孔页岩砖厂、苍梧县梨埠镇梨旺页岩砖厂、沈阳北斗旅游汽车有限公司、北海市鑫利水产有限公司、广西衡顺物流有限公司。 相似文献
25.
Power matters in closing the phenotyping gap 总被引:1,自引:0,他引:1
Meyer CW Elvert R Scherag A Ehrhardt N Gailus-Durner V Fuchs H Schäfer H Hrabé de Angelis M Heldmaier G Klingenspor M 《Die Naturwissenschaften》2007,94(5):401-406
Much of our understanding of physiology and metabolism is derived from investigating mouse mutants and transgenic mice, and
open-access platforms for standardized mouse phenotyping such as the German Mouse Clinic (GMC) are currently viewed as one
powerful tool for identifying novel gene-function relationships. Phenotyping or phenotypic screening involves the comparison of wild-type control mice with their mutant or transgenic littermates. In our study, we explored
the extent to which standardized phenotyping will succeed in detecting biologically relevant phenotypic differences in mice
generated and provided by different collaborators. We analyzed quantitative metabolic data (body mass, energy intake, and
energy metabolized) collected at the GMC under the current workflow, and used them for statistical power considerations. Our
results demonstrate that there is substantial variability in these parameters among lines of wild-type C57BL/6 (B6) mice from
different sources. Given this variable background noise in mice that serve as controls, subtle phenotypes in mutant or transgenic
littermates may be overlooked. Furthermore, a phenotype observed in one cohort of a mutant line may not be reproducible (to
the same extent) in mice coming from a different environment or supplier. In the light of these constraints, we encourage
researchers to incorporate information on intrastrain variability into future study planning, or to perform advanced hierarchical
analyses. Both will ultimately improve the detectability of novel phenotypes by phenotypic screening.
Carola W. Meyer and Ralf Elvert contributed equally to this work. 相似文献
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28.
Predicting the transfer of 137Cs to rice plants by a dynamic compartment model with a consideration of the soil properties 总被引:1,自引:0,他引:1
The factors governing chlorine transfer from Phaeozem and Greyzem soils to various important crop species (foodstuff and forage) were determined in natural conditions in the Kiev region of Ukraine. The stable chlorine concentration ratio (CR) values were the lowest in apple (0.5+/-0.3) and strawberry (2+/-1), higher in vegetables (5+/-3), seeds (15+/-7) and reached a maximum in straw (187+/-90). The average CR values of 36Cl were estimated for the most important crops using all experimental data on 36Cl and stable chlorine transfer into plants from various soils. It was experimentally shown that boiling potatoes in water leads to an equilibrium between 36Cl specific content in the water and moisture in the cooked potato. The 36Cl processing factor (PF) for boiling various foodstuffs is equal to the ratio of water mass in the cooked foodstuff to the total water mass (in the food and the decoction). 36Cl PF for cereal flour can be estimated as 1. The 36Cl processing factor for dairy products is equal to the ratio of residual water mass in the product to initial water mass in milk. At a 36Cl specific activity in soil of 1 Bq kg-1, the estimated annual dietary 36Cl intake into human organism (adult man) is about 10 kBq. Sixty to seventy percent of the above amount will be taken in via milk and dairy products, 7-16% via meat, 14-16% via bread and bakery items and 8-12% via vegetables. The highest annual 36Cl intake, 10.7 kBq, is predicted for 1-year-old children. The expected effective doses from annual 36Cl intake are higher for younger age groups, increasing from 0.008 mSv in adults to 0.12 mSv in 1-year-old children. 相似文献
29.
为研究不同的多点泄漏工况对管道流动参数的影响,基于流动方程建立数学模型,讨论泄漏后压力下降幅值与泄漏位置、泄漏点数的关系,在室内输气环道采集多点泄漏工况下的压力信号并对理论分析结果进行验证。结果表明:泄漏点的上游和下游压力均减小,越靠近泄漏点压力降越大;2个泄漏点之间压力也下降,越靠近上游泄漏点,压力下降幅度越大;泄漏点距起点越近,泄漏引起的压力降低幅值越大。压力下降的幅值受距离起点最近的泄漏点位置影响最大,且随着泄漏点数的增多而增大。 相似文献
30.