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1.
During the day, there are considerable variations in the climatic factors prevailing in these regions. This is especially so during the 24-hour daily cycle of the long, hot and dry summer (mid-May to midOctober). Such climatic conditions have had a considerable impact on the daily living pattern of family life in the same season, particularly in the urban areas. During the same 24-hour cycle, they have compelled the inhabitants to shift their living activities both vertically in section and horizontally in plan; they do this in pursuit of more acceptable, if not, desirable internal thermal environmental ambience.  相似文献   
2.
The restoration of relatively old masonry buildings, 1870-1920, represents about 119930 flats and offices in the 4-5 largest cities in Norway. Driving rain and a severe climate are the key factors for deterioration. The paper describes a case study at the city campus of the University of Oslo.  相似文献   
3.
During the winter of 1988/1989, the relationships between the prevalence of work-related health and indoor climate complaints and a number of building, management, workplace and personal characteristics have been investigated in a study in more than 60 office buildings located throughout the Netherlands. To collect the information, a questionnaire was prepared on health and indoor climate complaints and personal and workplace characteristics. A checklist was used to obtain information on building characteristics More than 7000 questionnaires were completed by the regular users of the buildings investigated. The results showed that the prevalence of symptoms was higher in air-conditioned buildings than in naturally or mechanically ventilated buildings. some other variables were also related with most work-related complaints after adjustment for selected management, personal, workplace and job characteristics. These included gender, work satisfaction in general, presence of allergies and/or respiratory symptoms, and personal control over temperature at the workplace. No differences were found in symptom prevalences between buildings with spray and steam humidification. The combination of air-conditioning and humidification did not lead to further increases in the prevalence of complaints as compared to buildings with only airconditioning or only humidification.  相似文献   
4.
选取位于粤东、闽西南地区的韩江流域为研究对象,基于CA-Markov模型对2050年流域土地利用空间格局进行预测,构建SWAT分布式水文模型,以未来土地利用情景和气候变化情景为变量进行水文模拟,分析不同情景下韩江生态流量的时空演变特征。结果表明,未来城镇化扩张将使梅江支流中上游成为韩江流域内生态流量对土地利用变化最为敏感的区域;土地利用和气候变化将导致韩江流域枯水期流量整体减小,枯水期流量对环境变化更加敏感;韩江流域生态流量变化特征将呈现从西南到东北由升到降的趋势,梅江支流中上游地区的生态流量将得到改善;梅江和汀江两大支流上游区域生态流量对气候变化更为敏感;韩江流域径流总量下降,但丰枯流量分化加剧,长期来看枯季生态流量保障风险可能进一步增大。  相似文献   
5.
基于MODIS - NDVI 数据,辅以线性回归法与分段线性回归法,并借助ArcGIS 软件,对辽宁 省2000—2014 年植被覆盖的动态演变过程进行分析。结果表明: ( 1) 时间上,辽宁省植被NDVI 在年 际尺度上呈现出明显的增大趋势,2005 年出现突变,多年平均NDVI 值为0. 496; 春季、夏季、秋季 以及植被生长季NDVI 突变年份分别为2006 年、2005 年、2009 年和2004 年,秋季波动变化的突变点 明显滞后; 植被生长最旺盛的季节为夏季,且集中于8 月。( 2) 空间上,辽宁省植被覆盖具有明显的 地域性差异,呈现出东部高、中西部低的分布特征; 辽宁省植被覆盖优良区与辽东山地的界限基本吻 合,植被覆盖贫乏区主要集中在朝阳市和阜新市的东北部地区。( 3) 辽宁省植被覆盖程度呈山地阴坡 高于阳坡的形态,并且植被覆盖程度最好的坡向为北偏西方向。( 4) 2000—2014 年辽宁省植被覆盖度 整体以维持现状和轻微改善为主,保持不变的区域集中于中东部地区,辽阳市与沈阳市一带有轻微退 化现象,辽西北地区改善情况较为明显。  相似文献   
6.
Climate change is forecast to bring more frequent and intense precipitation to New York which has motivated research into the effects of floods on stream ecosystems. Macroinvertebrate assemblages were sampled at 13 sites in the Mohawk River basin during August 2011, and again in October 2011, following historic floods caused by remnants of Hurricane Irene and Tropical Storm Lee. The annual exceedance probabilities of floods at regional flow‐monitoring sites ranged from 0.5 to 0.001. Data from the first 2 surveys, and from additional surveys done during July and October 2014, were assessed to characterize the severity of flood impacts, effect of seasonality, and recovery. Indices of total taxa richness; Ephemeroptera, Plecoptera, and Trichoptera (EPT) richness; Hilsenhoff's biotic index; per cent model affinity; and nutrient biotic index‐phosphorus were combined to calculate New York State Biological Assessment Profile scores. Analysis of variance tests were used to determine if the Biological Assessment Profile, its component metrics, relative abundance, and diversity differed significantly (p ≤ .05) among the four surveys. Only total taxa richness and Shannon–Wiener diversity increased significantly, and abundance decreased significantly, following the floods. No metrics differed significantly between the July and August 2014 surveys which indicates that the differences denoted between the August and October 2011 surveys were caused by the floods. Changes in taxa richness, EPT richness, and diversity were significantly correlated with flood annual exceedance probabilities. This study increased our understanding of the resistance and resilience of benthic macroinvertebrate communities by showing that their assemblages were relatively impervious to extreme floods across the region.  相似文献   
7.
Future climate change is expected to have wide ranging impacts on the hydrology of mountain rivers because of changes in the magnitudes and timing of rain and snow, as well as the significant spatial variability of topography and other catchment characteristics. In New Zealand, hydropower generation in mountain basins is the primary source of electricity and renewable energy resource in the country. The goal of this study was to simulate and evaluate the potential effects of climate change on hydropower operations in three mountain headwater lakes (lakes Pukaki, Tekapo, and Ohau) in the Upper Waitaki Basin of the central South Island. The TopNet hydrological model was used to estimate catchment runoff and lake inflows based on the 1990s (baseline), 2040s, and 2090s periods. Average temperature and precipitation results from an ensemble of 12 Global Circulation Models based on the IPCC 4th Assessment Report A1B emissions scenario were used as input to TopNet. Linked hydropower lake water balance models were developed and used to simulate hydropower operations including discharge, hydroelectric power generation, and spill based on TopNet future inflow predictions, projected electricity demand, and lake storage and outflow characteristics. Our results indicate that annual lake inflows increase under future climate scenarios, but that there are seasonal effects with increasing flows in winter and early spring, and summer flows decreasing somewhat as a result of increasing temperatures and greater winter rain with less snow. Although overall hydropower generation can increase with the increasing flows and projected electricity demand, the seasonal changes result in demand being met in winter and spring with potential shortfalls in summer and autumn. Maximum annual generation can be achieved for some generating stations, but generation will decrease at other stations and more spill will likely be required through the 2090s because of the seasonal changes. Therefore flood and drought risk could also increase for downstream areas. Results also indicate that by the 2090s electricity demand could exceed generation capacity for these headwater lakes. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
8.
Increasing concentrations of methane (CH4) in the atmosphere are projected to account for about 25% of the net radiative forcing. Biospheric emissions of CH4 to the atmosphere total approximately 400 Tg C y-1. An estimated 300 Tg of CH4-C y-1 is oxidized in the atmosphere by hydroxyl radicals while about 40 Tg y-1 remains in the atmosphere. Approximately 40 Tg y-1 of the atmospheric burden is oxidized in aerobic soils. Research efforts during the past several years have focused on quantifying CH4 sources while relatively less effort has been directed toward quantifying and understanding the soil sink for atmospheric CH4. Recent research has demonstrated that land use change, including agricultural use of native forest and grassland systems has decreased the soil sink for atmospheric methane. Some agricultural systems consume atmospheric CH4 at rates less than 10% of those found in comparable undisturbed soils. While it has been necessary to change land use practices over the past centuries to meet the required production of food and fiber, we need to recognize and account for impacts of land use change on the biogeochemical nutrient cycles in the biosphere. Changes that have ensued in these cycles have and will impact the atmospheric concentrations of CH4 and N2O. Since CH4 and N2O production and consumption are accomplished by a variety of soil microorganisms, the influence of changing agricultural, forest, and, demographic patterns has been large. Existing management and technological practices may already exist to limit the effect of land use change and agriculture on trace gas fluxes. It is therefore important to understand how management and land use affect trace gas fluxes and to observe the effect of new technology on them. This paper describes the role of aerobic soils in the global CH4 budget and the impact of agriculture on this soil CH4 sink. Examples from field studies made across subarctic, temperate and tropical climate gradients in grasslands are used to demonstrate the influence of nutrient cycle perturbations on the soil consumption of atmospheric CH4 and in increased N2O emissions. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
9.
山西省孝义市近40年气候变化特征分析   总被引:1,自引:1,他引:0       下载免费PDF全文
为了深入研究山西省孝义市气候变化特征,采用Mann-Kendall检验、滑动T检验及Morlet小波变换等方法对孝义市1975-2015年气候要素进行趋势估计、突变检验、周期分析及发展趋势预测。结果表明:近40年来,孝义市年平均气温呈显著上升趋势,突变年份为1996年,存在32、9 a长周期;年降雨量呈不显著下降趋势,突变年份为1990年,存在32、6 a长周期;年蒸发量呈显著性上升趋势,突变年份为1997年,存在32、10 a长周期;年平均相对湿度呈显著下降趋势,突变年份为1982、2003年,存在15、32 a长周期。孝义市1975-2015年年代际气候经历了"冷湿-暖湿-暖干"的变化过程,预测全境2017-2030年年代际气候将经历"冷湿-暖干"的变化过程。  相似文献   
10.
Water allocation along the Syr Darya River may be affected by climate change. Here we statistically model cooperation strategies, country profits, and sensitivity of cooperation, showing that the hydrological regime affects transboundary cooperation. Climate change in the twenty-first century may reduce glacial cover, and reducing stream flows, decreasing chances of cooperation and potentially raising conflicts. Comparison with other transboundary catchments in Central Asia indicates moderate-to-high risk of conflicts for the Syr Darya. A template is provided for assessment of the stability of cooperation in the Syr Darya basin, and in catchments similarly dependent on water availability.  相似文献   
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