52 resultados para Rawdon, Marmaduke, 1610-1669.
Resumo:
Zhikong scallop (Chlamys farreri) is an economically important aquaculture species in China; however, frequent mass mortality seriously affects the development of its industry. Genetic linkage map is useful for genetic improvement and selective breeding of C. farreri. Linkage maps were constructed using an intraspecific F-1 cross and amplified fragment length polymorphism (AFLP) markers. Thirty-two selected AFLP primer combinations produced 545 AFLP markers that were polymorphic in either of the parents and segregated in the progeny. Of these segregating markers, 166 were mapped to 19 linkage groups of the female framework map, covering a total of 1503.9 cM, with an average marker spacing of 10.2 cM; and 197 markers were assigned to 20 linkage groups of the male map, covering a total of 1630.7 cM, with 9.2 cM per marker. A sex-linked marker was mapped on the female map with zero recombination and a LOD of 27.3. The genetic length of C farreri genome was estimated as 1889.0 cM for the female and 1995.9 cM for the male. The coverage of the framework map was calculated as 79.6% for the female and 81.7% for the male. When the triplets and doublets were considered, the observed length of the map was calculated as 1610.2 cM with coverage of 85.2% for the female, and 1880.5 cM with coverage of 94.2% for the male. The genetic maps presented here will serve as a basis for the construction of a high-resolution genetic map and mapping of economically important genes. (C) 2004 Published by Elsevier B.V.
Resumo:
采集种子采收前和采收后的抱茎獐牙莱全植株,分别分析测试其钾、钠、钙、镁等矿物质元素的含量。结果表明:青海西宁廿里铺种植抱茎獐牙菜矿物质元素主要分布于植株的茎杆部位,矿物质元素含量在成熟种子采收前后具有动态性变化的特征。
Resumo:
用超临界萃取技术对产于青藏高原上的糖茶藨种子中脂肪酸进行萃取,其萃取率为12%。用毛细管气相色谱对萃取的脂肪酸进行了分离和分析。结果表明不饱和脂肪酸的质量分数在90%以上。其中α-亚麻酸(α-linolenic acid)为27.4%,У-亚麻酸(У-linolenic acia)为2.70%。亚油酸(1inoleic acid)40.0%,油酸(oleic acid)21.0%。[著者文摘]
Resumo:
It is a basic work to ascertain the parameters of rock mass for evaluation about stability of the engineering. Anisotropism、inhomogeneity and discontinuity characters of the rock mass arise from the existing of the structural plane. Subjected to water、weathering effect、off-loading, mechanical characters of the rock mass are greatly different from rock itself, Determining mechanical parameters of the rock mass becomes so difficult because of structure effect、dimension effect、rheological character, ‘Can’t give a proper parameter’ becomes one of big problems for theoretic analysis and numerical simulation. With the increment of project scale, appraising the project rock mass and ascertaining the parameters of rock mass becomes more and more important and strict. Consequently, researching the parameters of rock mass has important theoretical significance and actual meaning. The Jin-ping hydroelectric station is the first highest hyperbolic arch dam in the world under construction, the height of the dam is about 305m, it is the biggest hydroelectric station at lower reaches of Yalong river. The length of underground factory building is 204.52m, the total height of it is 68.83m, the maximum of span clearance is 28.90m. Large-scale excavation in the underground factory of Jin-ping hydroelectric station has brought many kinds of destructive phenomenon, such as relaxation、spilling, providing a precious chance for study of unloading parameter about rock mass. As we all know, Southwest is the most important hydroelectric power base in China, the construction of the hydroelectric station mostly concentrate at high mountain and gorge area, basically and importantly, we must be familiar with the physical and mechanical character of the rock mass to guarantee to exploit safely、efficiently、quickly, in other words, we must understand the strength and deformation character of the rock mass. Based on enough fieldwork of geological investigation, we study the parameter of unloading rock mass on condition that we obtain abundant information, which is not only important for the construction of Jin-ping hydroelectric station, but also for the construction of other big hydroelectric station similar with Jin-ping. This paper adopt geological analysis、test data analysis、experience analysis、theory research and Artificial Neural Networks (ANN) brainpower analysis to evaluate the mechanical parameter, the major production is as follows: (1)Through the excavation of upper 5-layer of the underground powerhouse and the statistical classification of the main joints fractures exposed, We believe that there are three sets of joints, the first group is lay fracture, the second group and the fourth group are steep fracture. These provide a strong foundation for the following calculation of and analysis; (2)According to the in-situ measurement about sound wave velocity、displacement and anchor stress, we analyses the effects of rock unloading effect,the results show a obvious time-related character and localization features of rock deformation. We determine the depth of excavation unloading of underground factory wall based on this. Determining the rock mass parameters according to the measurement about sound wave velocity with characters of low- disturbing、dynamic on the spot, the result can really reflect the original state, this chapter approximately the mechanical parameters about rock mass at each unloading area; (3)Based on Hoek-Brown experienced formula with geological strength index GSI and RMR method to evaluate the mechanical parameters of different degree weathering and unloading rock mass about underground factory, Both of evaluation result are more satisfied; (4)From the perspective of far-field stress, based on the stress field distribution ideas of two-crack at any load conditions proposed by Fazil Erdogan (1962),using the strain energy density factor criterion (S criterion) proposed by Xue changming(1972),we establish the corresponding relationship between far-field stress and crack tip stress field, derive the integrated intensity criterion formula under the conditions of pure tensile stress among two line coplanar intermittent jointed rock,and establish the corresponding intensity criterion for the exploratory attempt; (5)With artificial neural network, the paper focuses on the mechanical parameters of rock mass that we concerned about and the whole process of prediction of deformation parameters, discusses the prospect of applying in assessment about the parameters of rock mass,and rely on the catalog information of underground powerhouse of Jinping I Hydropower Station, identifying the rock mechanics parameters intellectually,discusses the sample selection, network design, values of basic parameters and error analysis comprehensively. There is a certain significance for us to set up a set of parameters evaluation system,which is in construction of large-scale hydropower among a group of marble mass.
Resumo:
科学地评价贵州的农业生态环境, 可以为西部大开发中的区域发展战略提供理论依据。本文应用模糊综合评价方法, 通过对贵州各个区域的自然、社会、经济环境的系统研究, 对贵州各区域农业生态环境进行了客观评价, 从定量角度对各区农业生态环境加以探讨; 并对西部大开发中贵州农业生态环境保护提出了合理建议。
Resumo:
了解过去是认识现在和预测未来的基础。晚全新世是PAGES研究的目标时段之一。寻找和解译最近2000年连续、高分辨率自然记录是古气候研究的热点与难点。本项研究有针对性地选择程海、草海和青海湖开展湖泊沉积物环境记录的精细研究,结合14C、210Pb和137Cs定年,系统探讨了碳酸盐碳氧同位素、纤维素碳氧同位素、有机质碳同位素以及介形虫壳体Li/Ca比值指标的古环境指示意义。 通过研究,本论文取得了如下成果和新的认识: 1. 建立了一套有效的四阶段湖泊沉积物有机质纤维素提取方法(5%NaOH碱洗、5%HCl酸洗、亚氯酸钠和冰醋酸混合溶液漂白以及17.5%NaOH碱洗),红外光谱鉴定提取物为纯的α-纤维素,表明该实验方法是可行的,为今后广泛开展湖泊沉积物纤维素稳定同位素研究打下了坚实基础。 2. 多指标综合辨识了程海和草海沉积物碳酸盐主要是自生碳酸盐。程海和草海沉积物有机质C/N比值结合有机质碳同位素结果表明两湖的有机质分别源于水生植物藻类和大型水草。程海和草海沉积物碳酸盐含量主要反映了湖区温度的变化。 3. 程海、草海沉积物碳酸盐与青海湖沉积物介形虫壳体氧同位素组成均反映了湖区降水/蒸发比。降水/蒸发比大的湿润期,碳酸盐δ18O值小;降水/蒸发比小的干旱期,碳酸盐δ18O值大。程海沉积物碳酸盐碳同位素组成影响因素复杂,除了受大气与湖水之间的CO2交换影响外,还受水生植物光合/吸收作用的影响;草海沉积物碳酸盐碳同位素组成更大的变化范围,反映了湖区水生植物光合/吸收作用的影响,其异常的正值可能指示了湖区细菌参与有机质碳同位素分馏过程。 4. 利用草海沉积物有机质纤维素氧同位素定量恢复了湖水氧同位素组成变化。在此基础上,结合碳酸盐氧同位素组成初步恢复了草海地区过去500年来温度变化历史:草海地区在过去500年明显存在四个冷期,包括1550-1610年,1670-1730年,1770-1870年和1890-1920年冷期,其中前三个发生在传统意义上的现代小冰期时段。与其它记录研究结果的一致性表明纤维素氧同位素结合碳酸盐氧同位素是恢复古温度变化的最有效途径之一,同时也为现代小冰期在中国西南地区的存在提供了湖泊沉积学方面的证据。 5. 不同类型水生植物湖泊,湖泊沉积物有机质δ13C值对湖泊初级生产力变化的响应过程不同。大型水草为主的湖泊(草海),其沉积物有机质δ13C值随湖泊生产力的增大呈现增加的变化趋势;藻类为主的湖泊(程海),其沉积物有机质δ13C随湖泊生产力的增大呈现减小的变化趋势,藻类易降解是导致δ13C值随湖泊生产力的增大呈现减小变化趋势的主要原因。 6. 程海沉积物碳酸盐和有机质碳同位素组成的正相关变化以及草海沉积物碳酸盐和有机质碳同位素组成的负相关变化.表明湖泊生产力变化并不是导致碳酸盐和有机质碳同位素正相关变化的主要原因,湖泊水生植物类型以及湖泊大小均起着重要作用。湖泊沉积物碳酸盐与有机质之间的碳同位素分馏(△δ13C)是一种有效的湖泊生产力指示剂,即使是在有微生物参与有机质碳同位素分馏过程的草海,△δ13C值也反映了湖泊生产力的变化过程。 7. 青海湖沉积物单一种属介形虫壳体胖真星介(Eucypris inflata)Li/Ca比值与气象记录以及邻近地区都兰和祁连山树轮宽度指数恢复的古温度变化序列的对比研究揭示,介形虫壳体Li/Ca比值与温度呈明显的负相关变化(Li/Ca比值高,温度低;Li/Ca比值低,温度高),表明介形虫壳体Li/Ca比值是一种有效的古温度代用指标。 8. 青海湖沉积物单一种属介形虫壳体胖真星介(Eucypris inflata)Li/Ca比值、氧同位素与反映太阳活动的大气14C含量和冰芯10Be含量的一致性变化表明青海湖地区温度和降雨量的同步变化主要受太阳活动控制。