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991.
叙述了NCGS测井的原理及元素含量计算方法;解决了现场测井中计算元素含量时必须得到的参数,如等效相对探测效率曲线的刻度、探管和井液中干扰(Fe、Ti、H)份额的扣除。用自己研制的仪器经山东几个煤田钻孔实测资料验证.计算的元素含量与岩芯化学分析对照结果,其精度不低于美国PGT公司和Schlumberger公司制造的仪器。此外,还介绍了连续测量获得的谱,经处理绘制成连续曲线,首次推出S_(511)、S_B、S_H/S_B等曲线,提供多种有用地质信息。  相似文献   
992.
陕北能源化工基地煤炭、石油、天然气、岩盐等矿产资源储量丰富,经过近20a的开发,已初步建成为中国重要的能源接续地和大型煤化工基地。但该区又具有水资源相对短缺、生态环境脆弱的特点,加之近年来煤炭生产和转化等资源开发增长速度较快,采煤造成的区域性环境污染与生态破坏问题较为突出,严重制约着该区的可持续发展。通过探索建立陕北能源化工基地生态补偿机制,解决了煤炭资源开发与生态环境保护的矛盾,使资源得到适度、可持续的开发利用,环境生态得到持续的恢复和改善,从而使该区的经济发展与保护生态环境相协调,最大限度的实现了可持续发展的战略。  相似文献   
993.
This article attempts to disentangle the determinants of the adoption of renewable energy support policies in developing and emerging countries. By analyzing policies already implemented in industrialized countries, we focus on the diffusion but not the invention of climate-relevant policies. We look at four different types of policies (renewable energy targets, feed-in tariffs, other financial incentives and framework policies) and consider both domestic factors and international diffusion mechanisms utilizing a discrete-time events history model with a logit link on a self-compiled dataset of grid-based electricity policy adoption in 112 developing and emerging countries from 1998 to 2009. In general, we find stronger support for the domestic determinants of policy adoption, but also substantial influence of international factors. Countries with a larger population and more wealth have a higher probability of adopting renewable energy policies. Only in some specific cases do natural endowments for producing renewable energy encourage governments to adopt policies, and hydro power resources even correlate negatively with the adoption of targets. Among the international determinants, emulation from colonial peers and membership within the EU seem to facilitate policy adoption. International climate finance is less relevant, as the Global Environmental Facility and the Clean Development Mechanism may only increase the adoption of frameworks and targets, but they have no influence on tariffs and incentives.  相似文献   
994.
The survey for the HEIFE(Atmosphere-Land Surface Processes Experiment at Heihe RiverBasin,Western China)is given in the paper.The following basic subjects for land-surface process-es in arid areas are studied:(1)the general characteristics of the energy budget on ground surfacein arid areas;(2)the parameterization of the land surface processes;(3)the interaction betweenoasis and its desert circumstances,a special phenomenon in arid areas.The analysis shows that thesensible heat flux in the surface energy budget is in the majority,and the latent heat flux may beneglected.The influence of atmospheric stratification stability on the turbulent transfer of energyand substance must be considered in parameterization of land surface processes in arid areas.The“cold island effect”phenomenon in oasis and the“humidity inversion”phenomenon in desert nearoasis are the result of the interaction between them.The results would improve the understandingof land surface processes in arid areas.  相似文献   
995.
We simulated the impact of anthropogenic heat release (AHR) on the regional climate in three vast city agglomerations in China using the Weather Research and Forecasting model with nested high-resolution modeling.Based on energy consumption and high-quality land use data,we designed two scenarios to represent no-AHR and current-AHR conditions.By comparing the results of the two numerical experiments,changes of surface air temperature and precipitation due to AHR were quantified and analyzed.We concluded that AHR increases the temperature in these urbanized areas by about 0.5℃-1℃,and this increase is more pronounced in winter than in other seasons.The inclusion of AHR enhances the convergence of water vapor over urbanized areas.Together with the warming of the lower troposphere and the enhancement of ascending motions caused by AHR,the average convective available potential energy in urbanized areas is increased.Rainfall amounts in summer over urbanized areas are likely to increase and regional precipitation patterns to be altered to some extent.  相似文献   
996.
As surface exchange processes are highly non-linear and heterogeneous in space and time, it is important to know the appropriate scale for the reasonable prediction of these exchange processes. For example, the explicit representation of surface variability has been vital in predicting mesoscale weather events such as late-afternoon thunderstorms initiated by latent heat exchanges in mid-latitude regions of the continental United States. This study was undertaken to examine the effects of different spatial scales of input data on modeled fluxes, so as to better understand the resolution needed for accurate modeling. A statistical procedure was followed to select two cells from the Southern Great Plains 1997 hydrology experiment region, each 20 km×20 km, representing the most homogeneous and the most heterogeneous surface conditions (based on soil and vegetation) within the study region. The NOAH-OSU (Oregon State University) Land Surface Model (LSM) was employed to estimate surface energy fluxes. Three scales of study (200 m, 2 and 20 km) were considered in order to investigate the impacts of the aggregation of input data, especially soil and vegetation inputs, on the model output. Model results of net radiation and latent, sensible and ground heat fluxes were compared for the three scales. For the heterogeneous area, the model output at the 20-km resolution showed some differences when compared with the 200-m and 2-km resolutions. This was more pronounced in latent heat (12% decrease), sensible heat (22% increase), and ground heat flux (44% increase) estimation than in net radiation. The scaling effects were much less for the relatively homogeneous land area with 5% increase in sensible heat and 4% decrease in ground heat flux estimation. All of the model outputs for the 2- and 20-km resolutions were in close agreement. The results suggested that, for this study region, soils and vegetation input resolution of about 2 km should be chosen for realistic modeling of surface exchange processes. This resolution was sufficient to capture the effects of sub-grid scale heterogeneity, while avoiding the data and computational difficulties associated with higher spatial resolutions.  相似文献   
997.
Passive energy dissipation devices (EDDs), such as viscous dampers, viscoelastic dampers, etc., have been used to effectively reduce the dynamic response of civil infrastructures, such as buildings and bridges, subject to earthquakes and strong winds. The design of these passive energy dissipation devices (EDDs) involves the determination of the optimal locations and the corresponding capacities. In this paper, we present two optimal design methodologies for passive EDDs based on active control theories, including H and H2 performances, respectively. The optimal design methodologies presented are capable of determining the optimal locations and the corresponding capacities of EDDs. Emphasis is placed on the application of linear matrix inequality (LMI) for the effective design of passive EDDs using the popular MATLAB toolboxes. One important advantage of the proposed approaches is that the computation of the structural response is not needed in the design process. The proposed optimal design methodologies have been applied to: (i) a 10‐storey building and a 24‐storey building both subject to earthquake excitations, and (ii) a 76‐storey wind‐excited benchmark building, to demonstrate the advantages of the proposed design methodologies over the conventional equal capacity design. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
998.
提出1种将消频散变换应用到海底地声参数反演的方法。对单一水听器接收声压信号进行消频散处理后,根据群延时差建立代价函数,反演得到主要海底参数,最后根据贝叶斯统计理论给出了待反演地声参数的边缘后验概率密度。对单层波导进行仿真证明这种新方法的有效性。  相似文献   
999.
夏一飞  萧耐园 《天文学报》2001,42(3):266-271
采用较完善的地球模型PREM,通过求解弹性体的基本运动方程,得到形变位移矢量,由此分别计算出因日月引潮力势和地球自转离心力势引起的地球的弹性形变能,它将为弹性地球运动的Hamilton表达式提供摄动项的量级估计,并将是理论上探讨地月系演化的一个重要方面。  相似文献   
1000.
Brazil's nationally determined contribution (NDC) pledged under the Paris Agreement has marked a new stage in its climate policy towards strengthening low-carbon economic development beyond the recent drastic cuts in emissions from deforestation. Brazil especially means to limit oil consumption driven by future economic growth and to increase energy efficiency and biofuel use in the transport sector. On the other hand, Brazil still aspires to become a major petroleum province given its huge reserves of ‘pre-salt’ oil. This article aims to clarify under what conditions low-carbon economic development and oil exploration can possibly be combined in Brazil and what would be the energy system, environmental and macroeconomic implications of enabling policies for doing so. To address these questions, an energy–economy computable general equilibrium (CGE) model of the Brazilian economy is used to simulate alternative scenarios up to 2030. The results first show that implementing the most recent energy plans, which take into account the new economic reality in Brazil, should lead to over 20% lower domestic CO2 emissions in 2030 than the indicative NDC target, and to the export of the bulk of newfound crude oil. Second, with the same level of oil production, deeper domestic decarbonization, triggered by additional carbon pricing and sustainable efficiency measures, appears achievable with very small gross domestic product (GDP) loss and maximum oil exports, while being aligned with a 2°C emission pathway. However, (i) extra oil exports may induce net additional emissions outside Brazil and be seen as a perverse incentive and (ii) the economic growth strategy based on high oil exports may hinder the necessary diversification of the Brazilian economy.

Key policy insights

  • Low-carbon development goals will strongly interact with oil policy in Brazil.

  • The 2030 NDC target should be easy to achieve considering the new economic reality in Brazil.

  • Deeper domestic decarbonization is achievable with very limited GDP loss and significant oil exports, while being aligned with a 2°C emission pathway.

  • A broad strategic vision is needed to reconcile climate policy, energy policy and other economic development objectives.

  相似文献   
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