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21.
应用灰色系统理论,根据江苏省地震工程研究院的地震科技开发资料,分别以项目负责人的年龄、学历、职称、职务、学科作为比较数列,对年度内完成的实际合同额进行了多因素灰色关联分析,排出了关联序。研究结果客观地揭示了开发能力与人的各种因素——年龄、学历、职称、职务、学科之间的相互关系,为市场经济条件下,地震科技人才的开发、培养和应用,提供了科学依据。  相似文献   
22.
To obtain detailed information on the pyrolysis characteristics, a thermogravimetric study on the pyrolysis of 14 typical medical waste compositions was carried out in thermogravimetric analysis (TGA) equipment using dynamic techniques in a stream of N(2). An index representing pyrolysis reactivity of waste was presented. Kinetic parameters were obtained by Coats-Redfern method and used to model the TG curve. The results showed that: (a) Plastic, protein, cellulosic material, synthetic fibre, and rubber entered pyrolysis process in succession. (b) There was one decomposition stage in the pyrolysis of one-off medical glove, operating glove, cellulosic waste, absorbable catgut suture and adhesive plaster, while other components had two obvious weight loss stages. (c) The obtained apparent activation energy for second stage pyrolysis was comparably higher than that for first stage. (d) Each stage was controlled by only one kinetic mechanism, in which kinetic parameters were constant. (e) The degradation kinetics of medical waste may be affected by special physical and chemical treatment in the product manufacturing process. (f) Among 13 waste samples, the pyrolysis index of cellulosic matter was the highest, which indicated cellulosic matter had strong pyrolysis reactivity. (g) With increasing heating rate, TG curve and DTG peak shifted to high temperatures and main reaction interval of the sample became longer.  相似文献   
23.
Abstract: Genebank collection databases can be used for ecogeographical studies under the assumption that the accessions are a geographically unbiased sample. We evaluated the representativeness of a collection of wild potatoes from Bolivia and defined and assessed four types of bias: species, species-area, hotspot, and infrastructure. Species bias is the sampling of some species more often than others. Species-area bias is a sampling that is disproportionate to the total area in which a species is found. Hotspot bias is the disproportionate sampling of areas with high levels of diversity. Infrastructure bias is the disproportionate sampling of areas near roads and towns. Each of these biases is present in the Bolivian wild potato collection. The infrastructure bias was strong: 60% of all wild potato accessions were collected within 2 km of a road, as opposed to 22%, if collections had been made randomly. This analysis can serve as a guide for future collecting trips. It can also provide baseline information for the application of genebank data in studies based on geographic information systems.  相似文献   
24.
电磁环境对采后芒果的生理影响   总被引:2,自引:0,他引:2  
系统研究了采后芒果在静电场,磁场,放电生成气环境下的生理变化。测试了呼吸速率,果体与果皮电解质渗出率,商品果率与病情指数等生理指标。研究结果表明,采后芒果在呼吸速率达到高峰之前电磁环境对其均有明显的作用,而在呼吸高峰之后,无明显影响。在我们设置的电磁环境参数中有几项显示保鲜作用。表1参6  相似文献   
25.
应用D412螯合树脂治理含镍电镀废水的研究   总被引:1,自引:0,他引:1  
本文研究了D412螯合树脂对Ni(Ⅱ)离子静态和动态的吸收性能,并且研究了使用D412树脂除去和回收电镀废水中镍的最佳条件。  相似文献   
26.
Improved predictions on the fate of organic pollutants in surface environments require a better understanding of the underlying sorption mechanisms that control their uptake by soils. In this study, we monitored sorption of nine aromatic compounds with varying physicochemical properties (hydrophobicity, electron-donor/acceptor ability and polarity), including two polycyclic aromatic hydrocarbons, two chlorobenzenes, two nitroaromatic compounds, dichlobenil, carbaryl and 2,4-dichlorophenol in aqueous suspension of four surface soils of eastern China. The tested soils were characterized with respect to organic carbon (OC) content, black carbon content, mineralogy, morphology and size fraction to assess the role of the diverse soil characteristics in sorption. The results of this study show that not only the solute hydrophobicity and the OC content of soil are important to the retention of organic pollutants, but also the solute molecular structure and the soil nature.  相似文献   
27.
为了研究天津市中心城区集中供应管网末梢水的抗生素耐药基因(antibiotic resistance genes,ARGs)污染特征,采集了天津市中心城区6个采样点的管网末梢水样,分别采用微孔滤膜正压过滤法及核酸吸附-洗脱法富集水中细菌和胞外核酸后,利用实时定量PCR技术对15种胞内ARGs和胞外ARGs进行定量检测....  相似文献   
28.
The development of process-based models to estimate ammonia emissions from animal feeding operations (AFOSs) is sought to replace costly and time-consuming direct measurements. Critical to process-based model development is conducting sensitivity analysis to determine the input parameters and their interactions that contribute most to the variance of the model output. Global and relative sensitivity analyses were applied to a process-based model for predicting ammonia emissions from the surface of anaerobic lagoons for treating and storing manure. The objectives were to compare global sensitivity analysis (GSA) to relative (local) sensitivity analysis (RSA) on a process-based model for ammonia emissions. Based on the first-order coefficient, both GSA and RSA showed the model input parameters in order of importance in process model for ammonia emissions from lagoon surfaces were: (i) pH, (ii) lagoon liquid temperature, (iii) wind speed above the lagoon surface, and (iv) the concentration of ammoniacal nitrogen in the lagoon. The GSA revealed that interactions between model parameters accounted for over two-thirds of the model variance, a result that cannot be achieved using traditional RSA. Also, the GSA showed that parameter interactions involving liquid pH had more impact on the model output variance than the single parameters: (i) temperature, (ii) wind speed, or (iii) total ammoniacal nitrogen. This study demonstrates that GSA provides a more complete analysis of model input parameters and their interactions on the model output compared to RSA. A comprehensive tutorial regarding the application of GSA to a process model is presented.  相似文献   
29.
<正>几十年地震预报实践说明,地震预报尚未成熟,远未达到实用化,目前仍属于摸索探索阶段。有些地震虽然说可能作预测预报,但即使预报了,对一个大城市而言也不会轻易疏散、停工停产,而且地震发生了城市的物质文明建设照样会遭到严重破坏。换个方式去思维去实践,即把城乡建筑的抗震性能提高了,尤其是住宅建筑和重  相似文献   
30.
介绍了弹性滑移支座的原理、构造和特点;通过对其在不同工况下的性能试验,研究了竖向荷载、位移幅值以及加载频率对弹性滑移支座力学性能的影响,并给出了试验值与理论计算值之间的对比。研究结果表明:弹性滑移支座具有良好的工作性能,滞回曲线饱满,耗能能力强;竖向荷载和加载频率对弹性滑移支座的力学性能有一定的影响,而位移幅值对其影响较小;弹性滑移支座的恢复力模型,可以用考虑速度的指数摩擦力模型来描述,并且模拟得较为准确。  相似文献   
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