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141.
1月28日,美国众议院通过经济刺激计划时的一项附加条款规定,部分救援资金只能“购买美国货”,任何基础设施项目要获得刺激方案的资金支持,所使用钢铁产品必须为美国生产。  相似文献   
142.
[案情介绍]2006年10月,某市甲房地产公司进行东方花园二期房地产开发,施工过程形成塌方,破坏了小区内相邻的8号楼的基础,造成房屋开裂,经市建设部门鉴定属危房。  相似文献   
143.
一、深化土地使用制度改革,规范土地市场建设的根本措施 1.深化土地使用制度改革,规范土地市场建设是盘活存量土地资产的有效途径 深化土地使用制度改革,规范土地市场建设,使土地资产逐步盘活,实现了土地的资产价值,在土地市场建设中发挥了应有的效应。当前我国正进行经济结构特别是产业结构和产品结构的调整,这些调整势必关系到或者直接涉及到土地利用结构的调整,要适应这个大趋势,抓住机遇,在经济结构调整中,通过深化土地使用制度改革,规范土地使用制度改革,规范土地市场建设,优化用地结构。  相似文献   
144.
Microsatellite markers have become one kind of the most important molecular tools used in various researches. A large number of microsatellite markers are required for the whole genome survey in the fields of molecular ecology, quantitative genetics and genomics. Therefore, it is extremely necessary to select several versatile, low-cost, efficient and time- and labor-saving methods to develop a large panel of microsatellite markers. In this study, we used Zhikong scallop (Chlamys farreri) as the target species to compare the efficiency of the five methods derived from three strategies for microsatellite marker development. The results showed that the strategy of constructing small insert genomic DNA library resulted in poor efficiency, while the microsatellite-enriched strategy highly improved the isolation efficiency. Although the mining public database strategy is time- and cost-saving, it is difficult to obtain a large number of microsatellite markers, mainly due to the limited sequence data of non-model species deposited in public databases. Based on the results in this study, we recommend two methods, microsatellite-enriched library construction method and FIASCO-colony hybridization method, for large-scale microsatellite marker development. Both methods were derived from the mi-crosatellite-enriched strategy. The experimental results obtained from Zhikong scallop also provide the reference for microsatellite marker development in other species with large genomes.  相似文献   
145.
This feeding trial was conducted to evaluate the potential of poultry by-product meal (PBM) as a protein source in the culture ofLitopenaeus vannamei. Seven isonitrogenous and isoenergetic diets were formulated to near to commercial diet with about 40% protein and 7.5% lipid. Fish meal was replaced by 0, 30%, 40%, 50%, 60%, 70% and 100% of PBM (diets 1-7). The diet with 100% fish meal was used as a control (diet 1). Post-larvae were reared in an indoor semi-closed re-circulating system. Each dietary treatment was tested in 4 replicate tanks (260 L) of 40 shrimp, arranged in a completely randomized design. The shrimps were hand-fed for three times a day to near-satiation (0700, 1200 and 1800) for 60d. Percentage weight gain, survival, feed conversion ratio (FCR), protein efficiency ratio (PER) and body composition of shrimps were measured. There were no significant differences (P>0.05) in growth performance among shrimps fed diets 1-5 (0-60% fish meal replacement). However, shrimps fed diet 7 (100% fish meal replacement) had significantly lower (P<0.05) growth than those fed diets 1-5 (0-60% fish meal replacement). Shrimp fed diets 2-4 (30%-50% fish meal replacement) showed significantly higher growth than those fed diets 6 and 7 (70% and 100% fish meal replacement, respectively). Survival ranged from 94.7% to 100.0% and did not differ significantly (P>0.05) among different experimental diets. No differences in body composition were found among shrimps fed different diets. These results showed that up to 70% of fish meal protein can be replaced by PBM without adversely affecting the growth, survival, FCR, PER and body composition of Litopenaeus vannamei.  相似文献   
146.
煤,早在800年前就被广泛用作工业生产的燃料,推动了当时工业的向前发展,随之发展起煤炭、钢铁、化工、采矿、冶金等工业。煤在地球上的储量丰富,除了作为燃料以取得热量和动能以外,更为重要的是从中制取冶金用的焦炭和制取人造石油,即煤的低温干馏的液体产品——煤焦油。经过化学加工,从煤炭中能制造出成千上万种化学产品,所以它又是一种非常重要的化工原料,我国相当多的中、小氮肥厂都以煤炭作原料生产化肥。煤也被人们誉为“黑色的金子”。  相似文献   
147.
A field work has been carried out to identify the occurrence of oil and oil products pollution in mangrove sediment from Red Sea of Yemen. The concentration of total petroleum hydrocarbons is from 700 ng/g at Kamaran Island station to 400 ng/g at Al-Hodiedah station, and the total organic carbon ( TOC) in samples ranges from 0.07% at Dhubab station to 0.03% at Kamaran Island station. This pollution is as a result of localized oil pollution and /or heavy ship traffic in the Red Sea and Gulf of Aden.  相似文献   
148.
本文利用地转风计算公式、增水公式和日本数值预报产品相结合的方法,计算由温带气旋诱发渤海湾风暴湖时的增水值,并结合天文湖资料,估算高潮位.应用该预报方法对渤海湾发生的"070304"风暴潮个例进行检验,预报值与实测值基本相当,是基层台站较实用的一种风暴潮预报方法.但此方法是否适用干其它造成风暴湖的影响系统有待于进一步求证.风暴潮的发生与风向、风速关系密切,一般当渤海湾盛行东北风或偏东风,且风向维持时间较长、风速较大时,易造成风暴潮的天气.日本数值预报产品对渤海风向、风速的预报对预报渤海的大风有较好的参考价值.  相似文献   
149.
论加强我国海洋突发公共事件的管理   总被引:2,自引:0,他引:2       下载免费PDF全文
在人类面临的众多突发公共事件中,很多与海洋有着非常密切的关系.近几年,虽然我国在危机管理方面已取得很大成绩,但对突发事件尤其是海洋突发事件的管理还很薄弱.加强对我国海洋突发公共事件的管理势在必行.  相似文献   
150.
A field work has been carried out to identify the occurrence of oil and oil products pollution in mangrove sediment from Red Sea of Yemen. The concentration of total petroleum hydrocarbons is from 700ng/g at Kamaran Island station to 400 ng/g at Al-Hodiedah station, and the total organic carbon (TOC) in samples ranges from 0. 07% at Dhubab station to 0. 03% at Kamaran Island station. This pollution is as a result of localized oil pollution and/or heavy ship traffic in the Red Sea and Gulf of Aden.  相似文献   
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