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121.
叙述了蓄水屋面在隔热方面的作用 ,从几个方面探讨了蓄水屋面的构造设计 ,并提出了应该注意的问题。  相似文献   
122.
从具有中国特色的风景画———山水画的历史发展入手,剖析画家的创作经历,认知其创作情感,可以挖掘其所反映的深层的人文精神。当前的风景画创作,应体现人文思想与精神关怀,拥有自我美好的心灵家园。  相似文献   
123.
论水资源法律体系及完善   总被引:4,自引:1,他引:3  
水资源既有私人物品的属性,又有公共物品的属性,二者相互混合,不能分开。水资源的这两种属性决定了对其的法律调整既有公法,又有私法,既有宏观的法律制度,又有具体的管制制度。构成我国水资源法律体系主要有水资源宪法法律制度,水资源环境法律制度,水资源民事法律制度和水资源行政法律制度。我国水资源法律体系的完善,除了理论上的创新外,仍需对有关的法律进行完善。  相似文献   
124.
Experiments were performed to determine the extent of cross‐contamination of DNA resulting from secondary transfer due to fingerprint brushes used on multiple items of evidence. Analysis of both standard and low copy number (LCN) STR was performed. Two different procedures were used to enhance sensitivity, post‐PCR cleanup and increased cycle number. Under standard STR typing procedures, some additional alleles were produced that were not present in the controls or blanks; however, there was insufficient data to include the contaminant donor as a contributor. Inclusion of the contaminant donor did occur for one sample using post‐PCR cleanup. Detection of the contaminant donor occurred for every replicate of the 31 cycle amplifications; however, using LCN interpretation recommendations for consensus profiles, only one sample would include the contaminant donor. Our results indicate that detection of secondary transfer of DNA can occur through fingerprint brush contamination and is enhanced using LCN‐DNA methods.  相似文献   
125.
In January 2012, 664 cases of pyrimethamine toxicity and 151 deaths were reported among cardiac patients that had recently received free medicines from pharmacy of Punjab Institute of Cardiology, Lahore, Pakistan. These patients, ages ranged from 58 to 75 years, were prescribed simvastatin, clopidogrel, aspirin soluble, isosorbide mononitrate, and amlodipine. On examination of medications being given to them, it was found that a particular batch of isosorbide mononitrate tablets was contaminated with 50 mg pyrimethamine. Cardiac patients were taking isosorbide contaminated with pyrimethamine twice daily (100 mg pyrimethamine/day), whereas therapeutic dose of pyrimethamine for malaria is 25 mg/week. Postmortem urine, cardiac blood, and femoral blood specimens of three deceased males were submitted to author's laboratory for analysis. Postmortem toxicological analysis revealed that pyrimethamine concentration fell within the range of 1–10 μg/mL by liquid chromatography. Clinical, autopsy, histopathological, and toxicological findings strongly suggested toxicity due to pyrimethamine accumulation that resulted in deaths of these cardiac patients.  相似文献   
126.
Disposing of items of forensic relevance in bodies of water is one countermeasure offenders can use to avoid detection. The impact of immersion in water has been explored for blood, saliva, and semen; however, few studies have assessed touch DNA. Here we report on the effect of exposure to water on the persistence of touch DNA over prolonged periods of time. To evaluate the persistence of cells from touch DNA, after water exposure, three substrates and two water types were tested: plastic, metal, and ceramic, submerged into seawater or tap water. Diamond™ Nucleic Acid Dye was used to stain cells deposited by touch. Cell counts before and after water exposure were compared to investigate cell loss over time, ranging from 6 hours to 5 days. A logarithmic increase in the percent of cells lost was observed over time when the data for substrate and water type conditions were combined. Substrate type influenced the persistence of cells, with the metal substrate retaining cells longer than plastic or ceramic. The influence of water type appeared dependent on the substrate, with varied cell persistence on metal whereas plastic and ceramic recorded similar cell loss over time between water types. The ability to visualize cells after exposure to water could assist in triaging evidence within operational forensic laboratories and allow for targeted sampling. This proof-of-concept study demonstrated that greater than 50% of cells can persist on various items submerged in aqueous environments for at least 5 days, highlighting the possibility for downstream DNA testing.  相似文献   
127.
中国村镇水环境治理研究现状探讨   总被引:1,自引:0,他引:1  
刘强  王学江  陈玲 《中国发展》2008,8(2):15-18
随着中国广大村镇地区经济的快速发展,水环境已面临前所未有的严峻挑战。针对村镇水环境治理自身的特点,该文对村镇水环境现状、特点、处理原则及适用于村镇实际的污水处理技术与再生利用等方面进行了探讨。  相似文献   
128.
根据地缘利益诉求(攻势/守势)与跨国流域水治理程度(工具性/制度性)两个指标,可以将"水安全外交"界定为国家以及相关行为体围绕跨境水资源安全问题展开的博弈行为。水安全外交包括冲突预防型、霸权引导型、水互动冷漠型和治理后现代型四种类型。作为霸权引导型的美国水安全外交战略,其核心是通过水的全球治理来巩固其全球霸权地位,主要表现在两个方面:一是通过大国的地缘性介入,保障其水外交的战略利益;二是通过对区域水治理体系的制度性嵌置和重构,保持其水外交的合法性和有效性。美国通过水外交的四条路径(联盟和议题联系方式、同水外交大国的协调方式、国际组织议题嵌入、网络化伙伴关系)推进水安全外交政策和安全战略的制定。在其水外交进程中,国内外的动因机制发挥了重要作用。美国通过水安全外交拓展自身在亚太的地缘利益诉求,推行美国价值观的水治理原则和规范,嵌构以美国为核心的水安全治理体系,遏制地区大国(特别是中国)的水话语权,以最终实现美国在区域水—能源—粮食纽带安全中的战略优势平衡。  相似文献   
129.
该文阐述了生态补偿的必要性,并以新安江流域为例,介绍了新安江流域生态补偿的现状以及现实中面临的困境,并对新安江流域水资源生态补偿长效机制进行了探讨。  相似文献   
130.
While there is a robust literature about using tradeable permits as a solution to pollution externalities, less work has applied these principles to the area of transboundary water management. This article proposes the use of transboundary water banking as a means for addressing issues of water externalities, conflict over water resources, and incentive compatibility. First, the article provides clarity to this discussion by synthesizing relevant literature over transboundary water governance, focusing on the experience between the United States and Mexico over the Colorado River. Second, the article formalizes the idea of a transboundary water bank and the efficiency of an auctioned versus grandfathered permit program. Third, the article provides a brief formulation of the market design elements of such a scheme, namely four conditions that enable a sort of Nash Equilibrium among agents. The article concludes by alluding to the parallels between energy and water markets. While only a start, this article seeks to catalyze more formal mathematical modeling of solutions to transboundary water governance.  相似文献   
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