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141.
研究了N甲基对二甲胺基苯乙烯吡啶碘盐系列化合物的合成、分离方法,通过可见吸收、MS谱、HNMR 谱及氮素测定分析产物,证实了其结构和理论预期的一致性 相似文献
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The primary goal of this study was to assess the effect of varying densities on serum reproductive parameters of immature rainbow trout Oncorhynchus mykiss. Experimental trout were maintained in intensive, pen-reared farms for 300 days in fresh water reservoirs. Initial densities were 4.6, 6.6, and 8.6 kg/m3 (40, 60, 80 ind./m3), indicated as SD1, SD2, SD3, and final densities were 31.1, 40.6, 49.3 kg/m3, respectively. A summary of the ovarian stages were observed by histological examination. Serum E2 (estradiol), T (testosterone) were evaluated by radioimmunoassay and FSH (follicle-stimulating-hormone), LH (luteinizing-hormone), vitellogenin, 17α,20β-P (17α,20βdihydroxy4-pregnen-3-one) were measured by enzyme-linked immunosorbent assay. Our findings demonstrated that ovarian development were retarded (from stage III to stage IV) at highest rearing density (SD3) after 180 days of intensive culture (over 40.6 kg/m3). In addition, we observed an inverse relationship between serum reproductive parameters and rearing density. Furthermore, compared to serum reproductive parameters of SD1, E2, T, FSH, vitellogenin, 17α,20β-P, GSI and LH of two higher density groups decreased firstly and significantly at 60 (over 15.9 kg/m 3 ), 180 (over 31.7 kg/m 3 ), 180 (over 40.6 kg/m3), 240 (over 36 kg/m3), 240 (over 36 kg/m3), 240 (over 45 kg/m3) and 300 (over 49.3 kg/m3) days, respectively. Comparing serum reproductive parameters within the same ovarian development stage of rainbow trout from varying densities revealed that higher population density also led to significantly lower overall serum reproductive parameters. Overall, this study presents the reproductive, endocrinological parameters of juvenile female rainbow trout at high rearing densities and indicates the need for rainbow trout (114.44±5.21 g, 19.69±0.31 cm) that are initially stocked at 6.6 or 8.6 kg/m3 should be classified and subdivided into lower density after 180 days of farming (not over 31.7 kg/m3). 相似文献
146.
2001年1月1日,上市公司开始全面实施《企业会计制度》,进行八项计提,新增了固定资产减值准备、在建工程减值准备、无形资产减值准备、委托贷款减值准备四项计提内容.这些会计制度的实施,一定程度上挤干了上市公司资产中的水分,体现了谨慎性原则,但也在一定程度上影响了上市公司业绩.从2001 年披露的年报分析,由于上市公司采用了新的《企业会计制度》,其主要财务指标所体现的业绩呈较大幅度的下降,上市公司亏损面和亏损额的增加引发了人们对上市公司业绩和盈利能力,乃至上市公司整体质量的讨论. 相似文献
147.
North China, whose total area is 420,000 km2, covers 2 provinces and 2 cities (Shanxi and Hebei provinces, Beijing and Tianjin) and the territories of Henan and Shandong provinces to the north of the Huanghe (Yellow) River, and part of the Inner Mongolia Autonomous Region and Liaoning Province. Most of this region, which is situated in the semi-humid, semi-arid continental climate temperate zone, gets an annual precipitation of 500-600 mm, whereas, the perennial average amount of total water resource is 50.99 billion m3, including 33.82 billion m3 of surface water, 32.94 billion m3 of ground water and 15.77 billion m3 of their duplication. Due to the intensive exploitation of water resource caused by the deficiency of water resource in North China, key elements of water balance was changed, runoff volume reduced, evaporation increased, vertical movement of moisture strengthened, water circulation pattern transformed from open system into regionally closed system; meanwhile, due to the incompetent water 相似文献
148.
This paper systematically analyzes and proves the favorable factors of utilizing the ports and the railways in Northeast China for the Asia-Europe land bridge transportation. It will be more beneficial to Dalian Port and HaDa (Harbin-Dalian) and Binzhou (Harbin-Manzhouli) railways in Northeast China to the Siberia railway in Russia than 1) to other ports and the corresponding railways in China, 2) to the Nakhodka Port in Russia and the corresponding railways and 3) to the Chongjin Port in North Korea and the corresponding railways. This paper also puts forward the reform measures to adopt the ports and the railways in the northeast region in China for the land bridge transportation and the problems in transportation policies and management systems. 相似文献
149.
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150.
一、依法落实“两公告一登记”工作关于对征地方案的实施,《中华人民共和国土地管理法》第46条规定:“国家征收土地的,依照法定程序批后,由县级以上地方人民政府予以公告并组织实施”。《中华人民共和国土地管理法实施条例》第25条规定:“征收土地方案经依法批准后,由被征收土地所在地的市、县人民政府组织实施,并将批准征地机关、批准文号、征用土地的用途、范围、面积以及征收土地补偿标准、农业人员安置办法和办理征地补偿的期限等,在被征用土地所在地的乡(镇)、村予以公告。被征收土地的所有权人、使用权人应当在公告规定的期限内,持土地权属证书到公告指定的人民政府土地行政主管部门办理征地补偿登记。 相似文献