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341.
首先通过理论分析了线缆在电场中产生的电流大小,其次使用带状线装置产生均匀场强,通过测量找出线缆感应电流与场强之间的传输函数关系,从而验证了BCI法与空间辐射场的等效性,这为将来我国汽车电子BCI法制定合适的试验限值提供了参考。  相似文献   
342.
通过与国内针刺生产设备的对比,对进口Dilo针刺技术的优势、设备构造、自动化性能,以及产品的指标参数等进行了阐述,认为采用先进生产设备不仅能够提高企业产品的产量和质量,而且对企业自身的发展有促进作用。  相似文献   
343.
Huang Q  Huang HQ 《Chemosphere》2012,87(1):68-76
Methyl parathion (MP) is an extensively used organophosphorus pesticide, which has been associated with a wide spectrum of toxic effects on environmental organisms. The aim of this study is to investigate the alterations of membrane protein profiles in zebrafish liver (ZFL) cell line exposed to MP for 24 h using proteomic approaches. Two-dimensional gel electrophoresis revealed a total of 13 protein spots, whose expression levels were significantly altered by MP. These differential proteins were subjected to matrix-assisted laser desorption/ionization tandem time-of-flight mass spectrometry analysis, and nine proteins were identified to be membrane proteins, among which seven were up-regulated, while two were down-regulated. In addition, the mRNA levels corresponding to these differential membrane proteins were further analyzed by quantitative real-time PCR. And the differential expression of arginase-2 was specially validated via Western blotting. Regarding the physiological functions, these proteins are involved in molecular chaperon, cytoskeleton system, cell metabolism, signal transduction, transport and hormone receptor respectively, suggesting the complexity of MP-mediated toxicity to ZFL cell. These data could provide useful insights for better understanding the hepatotoxic mechanisms of MP and develop novel protein biomarkers for effectively monitoring MP contamination level in aquatic environment.  相似文献   
344.
Global climate change, along with continued habitat loss and fragmentation, is now recognized as being a major threat to future biodiversity. There is a very real threat to species, arising from the need to shift their ranges in the future to track regions of suitable climate. The Important Bird Area (IBA) network is a series of sites designed to conserve avian diversity in the face of current threats from factors such as habitat loss and fragmentation. However, in common with other networks, the IBA network is based on the assumption that the climate will remain unchanged in the future. In this article, we provide a method to simulate the occurrence of species of conservation concern in protected areas, which could be used as a first-step approach to assess the potential impacts of climate change upon such species in protected areas. We use species-climate response surface models to relate the occurrence of 12 biome-restricted African species to climate data at a coarse (quarter degree-degree latitude-longitude) resolution and then intersect the grid model output with IBA outlines to simulate the occurrence of the species in South African IBAs. Our results demonstrate that this relatively simple technique provides good simulations of current species' occurrence in protected areas. We then use basic habitat data for IBAs along with habitat preference data for the species to reduce over-prediction and further improve predictive ability. This approach can be used with future climate change scenarios to highlight vulnerable species in IBAs in the future and allow practical recommendations to be made to enhance the IBA network and minimize the predicted impacts of climate change.  相似文献   
345.
The purpose of this article is twofold. First, evaluation scoring systems for triple bottom line (TBL) reports to date are examined and potential methodological weaknesses and problems are highlighted. In this context, a new assessment methodology is presented based explicitly on the most widely acknowledged standard on non-financial reporting worldwide, the Global Reporting Initiative (GRI) guidelines. The set of GRI topics and performance indicators was converted into scoring criteria while the generic scoring devise was set from 0 to 4 points. Secondly, the proposed benchmark tool was applied to the TBL reports published by Greek companies. Results reveal major gaps in reporting practices, stressing the need for the further development of internal systems and processes in order to collect essential non-financial performance data. A critical overview of the structure and rationale of the evaluation tool in conjunction with the Greek case study is discussed while recommendations for future research on the field of this relatively new form of reporting are suggested.  相似文献   
346.
Assessing climatic suitability provides a good preliminary estimate of the invasive potential of a species to inform risk assessment. We examined two approaches for bioclimatic modeling for 67 reptile and amphibian species introduced to California and Florida. First, we modeled the worldwide distribution of the biomes found in the introduced range to highlight similar areas worldwide from which invaders might arise. Second, we modeled potentially suitable environments for species based on climatic factors in their native ranges, using three sources of distribution data. Performance of the three datasets and both approaches were compared for each species. Climate match was positively correlated with species establishment success (maximum predicted suitability in the introduced range was more strongly correlated with establishment success than mean suitability). Data assembled from the Global Amphibian Assessment through NatureServe provided the most accurate models for amphibians, while ecoregion data compiled by the World Wide Fund for Nature yielded models which described reptile climatic suitability better than available point-locality data. We present three methods of assigning a climate-match score for use in risk assessment using both the mean and maximum climatic suitabilities. Managers may choose to use different methods depending on the stringency of the assessment and the available data, facilitating higher resolution and accuracy for herpetofaunal risk assessment. Climate-matching has inherent limitations and other factors pertaining to ecological interactions and life-history traits must also be considered for thorough risk assessment. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
347.
定性分析了高压架空线"多频谱电磁污染"产生的原因,定量计算了高压架空线周围多频谱电磁场的分布,讨论了多频谱电磁污染对人体健康产生的危害,最后提出了"电磁屏蔽"、"绿色"涂料等可行的防护措施.  相似文献   
348.
环境空间管控和环境空间规划是我国城市空间规划体系中的短板,我国亟需建立起一套城市环境空间管控体系,来参与城市空间规划体系的建立,进而彻底扭转城市环境污染被动治理的尴尬局面。构建覆盖城市各领域的环境空间管控体系是城市环境总体规划的主要任务。本文梳理了我国环境空间管控发展现状和问题,从城市环境总体规划的角度,在城市层面构建了由环境功能区划、以生态保护红线为核心的严格管控区以及环境承载调控等手段组成的环境空间管控体系,并以贵阳城市环境总体规划为案例,进行了环境空间管控体系的构建。最后提出了实施城市环境总体规划空间管控的政策建议,保障空间管控体系能够落地和发挥作用。  相似文献   
349.
总磷总氮在线水质分析仪实际水样测量结果与实验室国标方法测量结果存在着差异,本文分析了影响总磷总氮在线水质分析仪测量结果的因素。  相似文献   
350.
本方法通过对区域地震体波振幅传播特征的研究并测定地震能量辐射系数企图得到中强震孕育的源兆信息。本文给出了方法的思路、介绍了参数的物理意义及正常理论值的估计。这一方法无论在目前模拟台网的观测条件下或将来数字观测台网建成之后均可方便、快捷使用。还对方法的使用误差、震例效果和存在问题进行了讨论。  相似文献   
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