39 resultados para Navas de Tolosa, Batalla de, 1212


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次生林是中国森林的主体 ,对其进行合理的经营无疑对中国天然林资源保护及国家生态安全建设具有重大意义 .次生林的结构 (尤其是垂直结构 )是该林种合理经营的重要因素 .本文在以往研究的基础上 ,引入了分层疏透度的概念 ,并以透光分层疏透度表征林分的垂直结构 ;详细介绍了应用全天照片测定透光分层疏透度的方法与步骤 ,分析了透光分层疏透度在次生林结构研究和次生林的经营理论与技术研究中的应用前景

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利用电喷雾离子阱质谱对黄酮苷类化合物———芸香苷与二价金属铜的络合物在软电离质谱条件下的络合行为进行了系统分析。所形成的 1∶1、2∶1、2∶2和 3∶2等不同化学计量比的芸香苷铜离子 (Ⅱ )络合产物 ,分别用 [R -H +Cu]+ ,[2R -H +Cu]+ ,[2R -3H +2Cu]+ 和 [3R -3H +2Cu]+ 表示。在多级串联质谱实验中 ,主要得到糖苷键断裂丢失寡糖链末端的鼠李糖基与苷元连接的葡萄糖基及整个寡糖链等中性碎片 ,同时也有寡糖链开环断裂和失水反应发生。

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New kinds of hybrid materials containing covalently bonded Eu3+ (Tb3+) bipyridine complexes in a silica network have been prepared and their luminescence properties reported.

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规范化管理高科技高效益企业中国科学院成都生物研究所王海燕中共成都市委组织部张松中科院成都生物研究所于1988年开始创办药厂,药厂产值六年翻了六番,原始投资增值数百倍。如今,药厂已更名为地奥制药公司,成为拥有净资产2亿多元、年利税1亿元的集高科技、新产...

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海面反射、散射或自发辐射的各个波段的电磁波携带着海表面温度、海平面高度、海表面粗糙度以及海水所含各种物质浓度的信息。波浪破碎是海洋的一种重要现象,波浪破碎支撑着海-气之间的热通量和气体通量的交换,这些通量对于天气和气候都有深远影响。同时,波浪破碎使得海表的粗糙度增加,这对于海表散射电磁波有极大的影响,因此在处理雷达散射问题时,考虑波浪破碎的影响十分必要。 本文分析了雷达散射的两种模式,并阐述了波浪破碎在海表电磁波散射过程中的重要性。论文的创新点在于利用Kudryavtsev03模式,反演得到了波浪破碎率与风速的两种新关系式,同时得到了较高精度的风速反演的隐含模式。针对波浪破碎微波散射模式问题,论文主要研究结果如下: 1.在Kudryavtsev03模式的基础上,以黄兴忠的白冠覆盖率公式替代破碎率,利用ERS-1散射计数据,对Bragg散射模式和Kudryavtsev03模式的结果进行了比较。结果表明:在相同条件下,考虑波浪破碎的Kudryavtsev03模式明显优于纯Bragg散射模式。 2 对Kudryavtsev03模式进行了修正。通过与实测ERS-1散射计数据比较,表明修正后,入射角在18-35°范围内,模式的结果具有较高的精度。 3 利用修正后的模式及散射计数据,在入射角为30-35°范围内,反演破碎率,并对反演结果进行了拟合,得到了两个新的破碎率与风速的关系式。 4 利用修正后的模式及新的破碎率公式,在入射角为30-35°范围内,反演风速,具有较高精度。 5 利用反演的风速,根据经验关系式,推算了各种海洋物理量。

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Grazing by domestic herbivores is generally recognized as a major ecological factor and an important evolutionary force in grasslands. Grazing has both extensive and profound effects on individual plants and communities. We investigated the response patterns of Polygonum viviparum species and the species diversity of an alpine shrub meadow in response to long-term livestock grazing by a field manipulative experiment controlling livestock numbers on the Qinghai-Tibet Plateau in China. Here, we hypothesize that within a range of grazing pressure, grazing can alter relative allocation to different plant parts without changing total biomass for some plant species if there is life history trade-offs between plant traits. The same type of communities exposed to different grazing pressures may only alter relative species' abundances or species composition and not vary species diversity because plant species differ in resistant capability to herbivory. The results show that plant height and biomass of different organs differed among grazing treatments but total biomass remained constant. Biomass allocation and absolute investments to both reproduction and growth decreased and to belowground storage increased with increased grazing pressure, indicating the increasing in storage function was attained at a cost of reducing reproduction of bulbils and represented an optimal allocation and an adaptive response of the species to long-term aboveground damage. Moreover, our results showed multiform response types for either species groups or single species along the gradient of grazing intensity. Heavy grazing caused a 13.2% increase in species richness. There was difference in species composition of about 18%-20% among grazing treatment. Shannon-Wiener (H') diversity index and species evenness (E) index did not differ among grazing treatments. These results support our hypothesis.

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In order to effectively identify and accurately evaluate low resistivity reservoir in Dongpu depression, using various logging data synthetically, geological and logging characteristics are summarized in term of different blocks on the basis of core analysis, cutting logging, oil testing and commissioning data. The formation mechanism of low resistivity reservoir is studied, and the main factors that cause low resistivity reservoir are discovered. The first factor is fine lithology, high shale content and hydrophilic rock. The second factor is high salinity formation water. The third factor is light oil, high gas quantity dissolved and large difference density of oil-water. The last factor is low amplitude structure of reservoir and low differential degree of oil-water. According to the characteristics of low resistivity reservoir, the method of compound lithology, the method of movable fluid, the method of phase permeability and the method of nuclear magnetic resonance logging are put forward. The compound lithology criterion of distinguishing hydrocarbon is founded in term of different blocks on the basis of electrical efficiency. The evaluation models of reservoir parameters are founded; whose core is oil saturation and phase permeability. In order to calculate oil saturation, the compound lithology model on the basis of electrical efficiency theory is chosen on condition that there is only the combination logging data of acoustic and induction; the W-S model is chosen on condition that there is all-around logging data. The calculational precision of oil saturation in low resistivity reservoir of work area is enhanced when the selection method is utilized. There are 1212 layers of reservoir newly added by the old well reexamination in the ten oil areas. The coincidence rate of logging interpretation reaches 83.2 percent according to the 74 well-times of oil testing or commissioning, which indicates that the distinguishing method and evaluation models of low resistivity reservoir above are feasible.By the reexamination, a ten million tons of proved reserves related to the low resistivity reservoir are newly added, consequently, the groundwork is established to increase reserve and production of old oilfields in the east of China and new livingness is added for the petroleum exploration and development in Dongpu depression.

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The disequilibrium between supply and demand the east part of North China accelerated natural gas exploration in Bohai bay basin. Exploration practice showed that coal-derived gas is important resource. In searching of big to middle scaled coal derived gas field, and realize successive gas supply, the paper carried out integrated study on structural evolution of Pre-Tertiary and evaluation of reservoir forming condition of coal-derived gas. Study work of the paper was based on the following condition: available achievement in this field at present, good understanding of multiphase of tectonic movement. Study work was focused on geological evolution, source rock evaluation and dissection key factors controlling reservoir forming. Based on analysis of seismic data, drilling data, tectonic style of Pre-Tertiary was subdivided, with different tectonic style representing different tectonic process. By means of state of the art, such as analysis of balanced cross section, and erosion restoration, the paper reestablished tectonic history and analyzed basin property during different tectonic phase. Dynamic mechanism for tectonic movement and influence of tectonic evolution on tectonic style were discussed. Study made it clear that tectonic movement is intensive since Mesozoic including 2 phase of compressional movement (at the end of Indo-China movement, and Yanshan movement), 2 phase of extensional movement (middle Yanshan movement, and Himalayan movement), 2 phase of strike slip movement, as well as 2 phase of reversal movement (early Yanshan movement, and early Himalayan movement). As a result, three tectonic provinces with different remnant of strata and different tectonic style took shape. Based on afore mentioned study, the paper pointed out that evolution of Bohai bay basin experienced the following steps: basin of rift valley type (Pt2+3)-craton basin at passive continental margin (∈1-2)-craton basin at active continental margin (∈3- O)-convergent craton basin (C-T1+2)-intracontinental basin (J+K). Superposition of basins in different stage was discussed. Aimed at tectonic feature of multiple phases, the paper put forward concept model of superposition of tectonic unit, and analyzed its significance on reservoir forming. On basis of the difference among 3 tectonic movements in Mesozoic and Cenozoic, superposition of tectonic unit was classified into the following 3 categories and 6 types: continuous subsidence type (I), subsidence in Mesozoic and uplift for erosion in Cenozoic (II1), repeated subsidence and uplift in Mesozoic and subsidence in Cenozoic (II2), repeated subsidence and uplift in Mesozoic and uplift for erosion in Cenozoic (II3), uplift for erosion in Mesozoic and subsidence in Cenozoic (II4), and continuous uplift (III). Take the organic facies analysis as link, the paper established relationship between sedimentary environment and organic facies, as well as organic facies and organic matter abundance. Combined information of sedimentary environment and logging data, the paper estimated distribution of organic matter abundance. Combined with simulation of secondary hydrocarbon generation, dynamic mechanism of hydrocarbon generation, and thermal history, the paper made static and dynamic evaluation of effective source rock, i.e. Taiyuan formation and Shanxi formation. It is also pointed out that superposition of tectonic unit of type II2, type II4, and type I were the most favorable hydrocarbon generation units. Based on dissection of typical primary coal-derived gas reservoir, including reservoir forming condition and reservoir forming process, the paper pointed out key factors controlling reservoir forming for Carboniferous and Permian System: a. remnant thickness and source rock property were precondition; b. secondary hydrocarbon generation during Himalayan period was key factor; c. tectonic evolution history controlling thermal evolution of source rock was main factor that determine reservoir forming; d. inherited positive structural unit was favorable accumulation direction; e. fault activity and regional caprock determined hydrocarbon accumulation horizon. In the end, the paper established reservoir forming model for different superposition of tectonic units, and pointed out promising exploration belts with 11 of the first class, 5 of the second class and 6 of the third class.