46 resultados para 1106
Resumo:
绿色GDP指标的测算及国民经济核算体系(SNA)的绿化是当今生态学和经济学研究的热点,对于促进经济、社会、环境的可持续发展具有重要作用。本文从绿色GDP的概念和内涵入手,回顾了其提出的背景和理论基础,概述了绿色GDP的表现形式和几种广泛应用的指标,并分析了这些指标在国家和城市尺度的应用实践,探讨了绿色GDP与其它相关概念的联系和区别,就其研究的主要问题和发展方向提出了一些看法和展望。绿色GDP核算中存在的问题还有待于完善。
Resumo:
水利既是经济发展的基础 ,又是社会发展的基础 ,随着人口的快速增长 ,城乡居民生活水平的不断提高 ,给水利工作提出了更高的要求。特别是 1998年洪涝灾害和 2 0 0 0年干旱灾害造成的重大的损失 ,使人们更认识到水利在国民经济中的地位与作用。为此 ,文章系统地分析了建国 5 0年来中国水利事业在艰难的条件下所取得的重大成绩 ,针对我国水利面临的挑战进行了讨论 ,并根据中国的具体情况 ,从我国的实际出发 ,力求抓住主要矛盾 ,从中探讨了水利事业发展的方略。
Resumo:
从人工湿地除磷机理着手,综述了国内外有关湿地基质、湿地植物及微生物强化除磷的研究机理以及进展。深入研究多种基质组合对磷素的吸附与解析机理,可以从理论上推进诸多高效除磷基质的实际应用进程;植物间接净化作用及其与湿地水力停留时间的关系,是影响湿地植物选种和种植的重要依据;植物根际微环境以及植物与微生物的耦合作用可能是人工湿地除磷的主要途径之一;强调湿地的污水净化功能而忽视其生态服务功能,是湿地运行中普遍存在的认识错误。最后指出:湿地运行应采取高水力负荷、低污染负荷的方式,强调强化一级处理的重要性。
Resumo:
新型多功能蔬菜育苗母剂多功能蔬菜育苗母剂是中国科学院沈阳应用生态研究所最新科研成果,并获国家发明专利,现已被列入辽宁省“九五”期间重点推广计划项目,几年来在全国各地应用效果明显,深受广大菜农欢迎。多功能蔬菜育苗母剂可为菜苗提供全面合理的营养,促进苗齐...
Resumo:
Electrochemical properties of rare earth AB(3)-type hydrogen storage alloys as negative electrode material and a polymer instead of 6 M KOH aqueous solution as solid state electrolyte in MH-Ni battery have been investigated at room temperature and 28degreesC first time. The partial replacement of Ni by Al and Mn elements increases the specific capacity and cycle stability of the alloy.
Resumo:
The complex fluorides of AZnF(3) (A = Na, K), which are isostructural with perovskite phases were obtained by the method of hydrothermal synthesis at 160-220 degrees C. Compared with traditional high-temperature solid-state method, the products were pure and contained lower amount of oxygen.
Resumo:
本文介绍用兰州化物所制备的Ag_2WO_4,MgO/AgVO_3催化剂分析含氟量很高的高分子化合物中的碳、氢的方法。该法的优点是快速、简便、燃烧温度低。测定的绝对误差不大于0.3%。 2 仪器和试剂: Carlo Erba 1106型元素分析仪,精度为lμg的天平,锡箔压制的样品小舟。Ag_2WO_4,MgO/AgVO_3兰州化物所制,镀银还原铜自制。氧气、氦气的纯度为99.999%。
Resumo:
人参为五加科植物人参(Panax ginseng C.A.Mey.)的干燥根。红参则是鲜人参洗净后经高温蒸气加热后干燥而制得的产品。有关人参中皂甙、氨基酸、多肽、挥发油、微量元素等成分的研究国内外均有大量的报道。但关于红参中碳、氢、氮元素的研究以及自动定量方法国内外尚未见报道。 1.仪器:1106型元素自动分析仪(意大利)其配套设备包括B-5000型记录仪,微处理机和电子天平。 2.人参样品:1号红参由吉林省抚松县参茸公司提供。2号红参由抚松县漫江参场提供。3号红参为抚松县参场提供。4号红参由延边地区提供。5号红参由集安县新开河参场提供。上述样品均为6年生。
Resumo:
贝类养殖是我国海水养殖业中最重要的组成部分之一。贝类人工大规模养殖中的关键环节是种苗的人工繁育,早期幼虫能否正常生长发育,对幼虫变态和变态后生长率及成活率有很大的影响,直接关系到生产产量和经济效益,所以,了解幼虫发育机制对于生产实践具有重要的指导意义。 文蛤(Meretrix meretrix)是一种在东亚各国沿海和滩涂地区广泛分布的双壳贝类,是我国一种重要的经济品种。本论文以文蛤幼虫为研究对象,分别对文蛤幼虫发育过程中贝壳形成相关的铁蛋白(MmeFer)、营养及变态相关的组织蛋白酶B(MmeCB)及变态过程中细胞凋亡相关的caspase三个基因进行了克隆,分析了基因及编码蛋白在担轮幼虫期(L1)、D形幼虫期(L2)、壳顶幼虫期(L3)和稚贝期(L4)的时空表达特征,解析了其可能的功能,并研究了相应酶类的特异性抑制剂作用对幼虫发育过程的影响,进行了目标蛋白的功能验证,详述如下: 研究结果显示,在文蛤胚胎发育到原肠胚时放入不含铁离子的人工海水中培养,发育成无壳的畸形,随着人工海水中铁离子添加浓度的升高,幼虫长出壳状组织接近正常状态;而发育到L1期幼虫放入不含铁离子的人工海水中培养却可以发育出正常的壳,推测铁和铁代谢相关蛋白在幼虫贝壳初始形成有重要的作用。根据构建的文蛤幼虫cDNA文库中提供的序列信息,从文蛤中克隆了与铁离子代谢密切相关的铁蛋白(MmeFer)的全长cDNA 序列;通过Real time PCR发现,MmeFer mRNA的表达量在贝壳形成前后有明显改变;整体原位杂交结果显示MmeFer mRNA在L1期的表达部位刚好是贝壳生成的起始部位,推断文蛤铁蛋白与文蛤幼虫贝壳初始形成密切相关。 利用文蛤幼虫cDNA文库中的EST信息在幼虫中克隆到文蛤组织蛋白酶B(MmeCB)全长cDNA序列;通过整体原位杂交分析发现MmeCB mRNA在L2至L4期幼虫的消化腺部位表达,而且在L2期的幼虫表皮也有表达,说明MmeCB可能和幼虫消化相关,而且可能参与幼虫从表皮摄取营养的过程。利用MmeCB特异性抑制剂(CA074Me)处理饥饿幼虫,发现其生长受到明显抑制,验证了MmeCB参与幼虫表皮营养代谢的推论。利用免疫组织化学技术,研究了MmeCB蛋白在文蛤幼虫中的时空分布,发现其在L2期幼虫表面和胃部有阳性信号,而在L3期,MmeCB在幼虫面盘基部有强烈的表达,提示MmeCB在文蛤幼虫中不仅起到营养的作用,而且可能和幼虫附着变态有关。利用CA074Me分别处理文蛤胚胎和变态期幼虫,发现抑制MmeCB的活性对胚胎发育和幼虫变态都有显著影响。研究结果提示MmeCB在幼虫发育各阶段均具有重要的生物学功能。 根据caspase在不同物种中的保守区域设计简并引物,在文蛤幼虫中扩增到cDNA序列片段;检测有活性的caspase在文蛤幼虫各发育时期的分布部位,发现其在L1至L3期幼虫中都有分布,说明整个幼虫形态变化过程中都有caspase的参与;细胞凋亡检测结果显示,幼虫主要发生细胞凋亡的部位在L3期幼虫的面盘,即变态过程中要退化的器官,说明细胞凋亡可能是文蛤幼虫变态过程中面盘退化的主要机制;用caspase特异性抑制剂处理变态前幼虫,发现幼虫变态率下降,初步验证了caspase在文蛤幼虫变态过程中的作用。 通过对上述三种基因的研究,分别探讨了文蛤幼虫发育阶段中的几个主要事件(L1期到L2期的贝壳形成、L2到L3期的幼虫营养摄食及L3到L4期的附着变态)相关的基因及其功能,为研究贝类生长发育调控的分子机理提供了新的线索。
Resumo:
alpha-葡萄糖苷酶是一类能够催化碳水化合物alpha-1,4-糖苷键水解的酶,是动物体内许多代谢途径中的关键酶,具有多方面的靶向药理活性。研究表明,alpha-葡萄糖苷酶与糖尿病,艾滋病,恶性肿瘤、溶酶体贮积症等疾病的发生机制有重要关系,已经成为治疗这些疾病的重要靶点。 海带(Laminaria japonica) 属褐藻门、海带属植物。自二十世纪四十年代从日本引入中国以来,已成为中国沿海重要的海洋经济作物。海带藻体叶片部分大都用来提炼碘、甘露醇和藻酸盐,但其假根部分一直被当作化工工业和食品工业的废料,而未得到有效的利用。在中国的沿海一带,海带根作为一种抗糖尿病的民间药物,有很长的历史。因此从海带根中提取分离降血糖成分并研究其作用机制将具有重要的意义。 本论文第一部分进行了海带根中具有alpha-葡萄糖苷酶抑制作用的活性组分的筛选。首先我们按照海带根中所含成分的极性不同进行了提取分离,即将海带根乙醇提取物依次用石油醚、乙酸乙酯、正丁醇萃取。结果乙醇粗体物、石油醚部位、乙酸乙酯部位、正丁醇部位与水部位的酶抑制IC50分别为1589µg/L、970µg/L、 380µg/L、1616µg/L、1106µg/L。乙酸乙酯部位的酶抑制活性最强。 本论文第二部分对海带根乙酸乙酯部位的提取物的体内降糖活性进行了研究,结果表明乙酸乙酯部位可以降低糖尿病大鼠餐后血糖,与阴性对照差异极显著(P<0.01)。小鼠服药后表现出的生命体征与伺服拜糖平后表现出的生命体征类似。 在以上工作基础上我们以alpha-葡萄糖苷酶的抑制活性为导向,用天然产物化学的方法对活性成分进行追踪,通过光谱、波谱与理化性质鉴定出了具有显著alpha-葡萄糖苷酶抑制活性的化合物:丁基-异丁基-邻苯酸二甲酯,并对其进行了酶抑制动力学研究。研究表明丁基-异丁基-邻苯酸二甲酯对alpha-葡萄糖苷酶表现为非竞争性抑制类型,IC50达到13.6μg/mL,且Km=2.39 g/L 本研究工作为进一步研究海带根降血糖成分的作用机理提供了研究基础。
Resumo:
Amplified fragment length polymorphisms (AFLPs) were used for genome mapping in the Pacific Oyster Crassostrea gigas Thunberg. Seventeen selected primer combinations produced 1106 peaks, of which 384 (34.7%) were polymorphic in a backcross family. Among the polymorphic markers, 349 were segregating through either the female or the male parent. Chi-square analysis indicated that 255 (73.1%) of the markers segregated in a Mendelian ratio, and 94 (26.9%) showed significant (P < 0.05) segregation distortion. Separate genetic linkage maps were constructed for the female and male parents. The female framework map consisted of 119 markers in 11 linkage groups, spanning 1030.7 cM, with an average interval of 9.5 cM per marker. The male map contained 96 markers in 10 linkage groups, covering 758.4 cM, with 8.8 cM per marker. The estimated genome length of the Pacific oyster was 1258 cM for the female and 933 cM for the male, and the observed coverage was 82.0% for the female map and 81.3% for the male map. Most distorted markers were deficient for homozygotes and closely linked to each other on the genetic map, suggesting the presence of major recessive deleterious genes in the Pacific oyster.
Resumo:
本文研究了氢化物发生无色散原子荧光法测定青藏高原中草药中的微量砷、锑、硒和汞的方法。在选定的最佳工作条件下, 14种干扰元素的含量低于允许存在量, 不影响测定。检出限(μg/m L ) 为: A s1.3, Sb0.39, Se0.24, Hg0.44; 9次测定的相对标准偏差(% ) 为A s2.4~ 4.2,Sb2.5~ 5.6, Se3.1~ 5.0, Hg3.8~ 5.9。4个元素的回收率为94.7~ 105.4%。本方法简便, 快速、灵敏、准确, 成功地应用于青藏高原20余种中草药中A s、Sb、Se 和Hg 的测定
Resumo:
The Indian monsoon, an integral part of the global climate system, has been extensively investigated during the past decades. Most of the proxy records are derived from marine sediments and focused on time periods of the late Miocene and Pleistocene. The Pliocene represents a period when Earth’s boundary conditions underwent dramatic changes. However, variations of the Indian monsoon during the Pliocene and its forcing mechanisms have remained unclear. The Yuanmou Basin, located in the region of the Indian monsoon, provides an ideal target for understanding the Pliocene history of Indian monsoon variations. Detailed investigations on the lithostratigraphy, magnetostratigraphy and limnology of a 650-m-thick fluvio-lacustrine sedimentary sequence from the basin are carried out in the present study. The clay and clay-plus-fine-silt fractions of the sediments are referred to the midlake-facies components, and changes in the percentages of both fractions generally reflect changes in the water level of the lakes developed in the basin closely related to variations in the intensity of the Indian monsoon. Whereas the greenish-gray lacustrine mud beds represent the environment of deep-water lakes, and the frequency of individual lacustrine mud beds is considered to indicate the frequency of the deep-water lakes developed in the basin associated with the variability of the Indian monsoon. The proxy data suggest that the Indian monsoon experienced abrupt shifts at 3.53, 3.14, 2.78 and 2.42 Ma, respectivey. 1) Since 3.53 Ma, the midlake-facies components displayed a general trend of increase in the concentrations, accompanied by an increase in the sedimentation rate from an average ~10 to 25 cm ka–1. The data suggest that high stands of the lakes in the basin rose progressively, implying a gradual intensification of the Indian monsoon since that time. This shift occurred coeval with the accelerated uplift of the northern Tibetan Plateau, denoting a close link between the Indian monsoon strengthening and the Tibetan Plateau uplifting. 2) 2.78 Ma ago, the concentrations of the midlake-facies components decreased abruptly and the dominant fraction of the sediments turned to fluvial sands. The data indicate that lakes in the basin disappeared, reflecting a dramatic decline in the intensity of the Indian monsoon at that time. This shift coincided with the formation of extensive Northern Hemisphere ice sheets, implying a quick response of the low-latitude monsoon regime to the high-latitude glaciation. 3) At 3.14 Ma, the initial appearance of blackish-grey mud beds with long durations and occasional occurrences of lacustrine mud beds indicate that the basin was overall dominated by shallow lakes, implying a shift to decreased variability of the Indian monsoon at that time. At 2.42 Ma, an increase in the frequency and a decrease in the duration of the lacustrine mud beds suggest that deep-water lakes were frequently developed in the basin, denoting a shift to increased variability of the Indian monsoon at that time. The former shift coincides with the onset of large-scale glaciation in the circum Atlantic region and the latter corresponds to the inception of predominance of the 41 ka periodicity in Northern Hemisphere ice-sheet cover fluctuations, presumably suggesting a physical link between the Indian monsoon system and the high-latitude ice sheets in the Northern Hemisphere.