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91.
甘肃西部地区高放废物处置库场址预选调查   总被引:1,自引:0,他引:1  
本文根据高放废物处置库场址选择的基本要求,对区域地质及深部构造特征、新构造运动及地震分布规律进行了调查,确定北山南带地区为稳定区。在稳定区内根据处置库有利围岩的出露情况,结合岩体工程地质特征分析,初步选出了4个以花岗岩为主体的场址预选区。经综合分析,认为在4个场址预选区中,以I号预选区的条件最优,其次是Ⅱ号预选区,再次是Ⅲ号和Ⅳ号预选区。场址区的最后确定尚待进一步调查和论证。  相似文献   
92.
We measured the emissions of volatile aliphatic amines and ammonia produced by the manure of beef cattle, dairy cows, swine, laying hens and horses in livestock buildings. The amine emissions consisted almost exclusively of the three methylamines and correlated with those of ammonia. The molar emission ratios of the methylamines to ammonia, and data on NH3 emissions from animal husbandry in Europe, together with global statistics on domestic animals, were used to estimate the global emissions of amines. Annual global methylamine-N input to the atmosphere from animal husbandry in 1988 was 0.15±0.06 TgN (Tg=1012 g). Almost 3/4 of these emissions consisted of trimethylamine-N. This represents about half of all methylamine emissions to the atmosphere. Other sources are marine coastal waters and biomass burning.Possible reaction pathways for atmospheric methylamines are shown. Among various speculative but possible products N2O and HCN are of interest because the emission of methylamines could contribute to the global budgets of these compounds. Maximum atmospheric N2O production from methylamines are below 0.4 Tg N/year, which is less than 10% of the annual N2O growth rate. Although we do not expect the methylamine emissions to contribute in a major way to the atmospheric N2O budget, more studies are needed to establish this conclusion beyond doubt. Similar conclusions hold for HCN.  相似文献   
93.
Conclusions Some bituminous coals, mostly of high volatile rank, sampled from various coalfields contained on average 0.5 m3 t–1 nitrogen and 0.13 m3 t–1.Nitrogen is released more readily than methane during coal winning but the volumes of nitrogen released are small compared with ventilation quantities and are only likely to be of significance for detailed oxygen deficiency studies.  相似文献   
94.
陕北煤炭基地的矿井水资源及利用   总被引:10,自引:2,他引:10  
范立民  李保平 《地下水》2007,29(5):1-3,7
简要论述了陕北地区煤矿开发的水文地质条件,对矿井水资源量、水质及利用途径进行了阐述.该区大型煤矿每天排水1 500~3 000 m3,中型煤矿也有500 m3左右,小煤矿每天排水30~100 m3,利用好矿井疏干水,不仅可以解决能源化工基地建设的用水需求,而且符合国家产业政策和环境保护的要求,是陕北能源化工基地建设的必然选择.  相似文献   
95.
Natural underground coal fires are fires in coal seams occurring subsurface. The fires are ignited through a process named spontaneous combustion, which occurs based on a natural reaction but is usually triggered through human interaction. Coal mining activities expose coal to the air. This leads to the exothermal oxidation of the carbon in the coal with the air's oxygen to CO2 and – under certain circumstances – to spontaneous combustion. Coal fires occur in many countries world wide – however, currently the Chinese coal mining industry faces the biggest problems with coal fires. Coal fires destroy the valuable resource coal and furthermore lead to many environmental degradation phenomena such as the deterioration of surrounding vegetation, land subsidence and the emission of toxic gasses (CO, N2O). They additionally contribute to the emission of green house relevant gasses such as CO2 and CH4 to the atmosphere.In this paper we present thermal characteristics of coal fires as measured in-situ during a field campaign to the Wuda coal fire area in south-central Inner Mongolia, China. Thermal characteristics include temperature anomaly measurements at the surface, spatial surface temperature profiles of fire areas and unaffected background areas, diurnal temperature profiles, and temperature measurements inside of coal fire induced cracks in the overlying bedrock. For all the measurements the effects of uneven solar heating through influences of slope and aspect are considered.Our findings show that coal fires result in strong or subtle thermal surface anomalies. Especially the latter can easily be influenced by heating of the surrounding background material through solar influences. Temperature variation of background rocks with different albedo, slope, aspect or vegetation cover can substantially influence the detectability of thermal anomalies. In the worst case coal fire related thermal anomalies can be completely masked by solar patterns during the daytime. Thus, night-time analysis is the most suitable for thermal anomaly mapping of underground coal fires, although this is not always feasible. The heat of underground coal fires only progresses very slowly through conduction in the rock material. Anomalies of coal fires completely covered by solid unfractured bedrock are very weak and were only measured during the night. The thermal pattern of underground coal fires manifested on the surface during the daytime is thus the pattern of cracks and vents, which occur due to the volume loss underground and which support radiation and convective energy transport of hot gasses. Inside coal fire temperatures can hardly be measured and can only be recorded if the glowing coal is exposed through a wider crack in the overlaying bedrock. Direct coal fire temperatures measured ranged between 233 °C and 854 °C. The results presented can substantially support the planning of thermal mapping campaigns, analyses of coal fire thermal anomalies in remotely sensed data, and can provide initial and boundary conditions for coal fire related numerical modeling.In a second paper named “Thermal Characteristics of Coal Fires 2: results of measurements on simulated coal fires” [Zhang J., Kuenzer C., Tetzlaff A., Oettl D., Zhukov B., Wagner W., 2007. Thermal Characteristics of Coal Fires 2: Result of measurements on simulated coal fires. Accepted for publication at Journal of Applied Geophysics. doi:10.1016/j.jappgeo.2007.08.003] we report about thermal characteristics of simulated coal fires simulated under simplified conditions. The simulated set up allowed us to measure even more parameters under undisturbed conditions — especially inside fire temperatures. Furthermore we could demonstrate the differences between open surface coal fires and covered underground coal fires. Thermal signals of coal fires in near range thermal remotely sensed imagery from an observing tower and from an airplane are presented and discussed.  相似文献   
96.
江苏南部地区煤层气资源   总被引:1,自引:0,他引:1  
李建青 《江苏地质》2002,26(4):200-202
根据江苏南部地区二叠系龙潭组煤系的分布和规模、煤矿瓦斯涌出特征、煤的产气能力、煤层的储集条件等煤层气地质条件综合研究工作,认为该区煤层气资源存在一定的勘探开发前景,对各典型含煤区块煤层气综合评价出有远景区(A类)、较有远景区(B类)和远景差区(C类)。  相似文献   
97.
云南禄丰煤岩与围岩中富勒烯(C60)物质的初步探索   总被引:3,自引:0,他引:3  
中国云南煤中是否存在富勒烯还没有科学定论。本工作运用高效液相色谱方法,对中国云南禄丰晚三叠世煤岩及其围岩中是否存在天然富勒烯物质的问题进行了探索性研究;同时发展了适于从复杂地质样品中分离纯化富勒烯和定性与定量检测富勒烯的一套技术方法。结果显示,从定性角度有两个样品确实存在富勒烯。本文据此提出,富勒烯的赋存与煤岩/围岩交互相上的含煤碳质泥岩有着密切的关系。下一步研究应着重调查比煤岩与顶板和底板界面层并大力研究其中天然富勒烯的地学成因。本工作的意义还在于为今后我国加入和独立开展以富勒烯类物质(如C60/C70)及其衍生物质(如He C60 C70)作为地球化学示踪物的古地球突变大事件的研究,奠定了实验方法学基础。  相似文献   
98.
文章通过对废物资源化利用的历史回忆,从能量一经济-环境的复合系统,论述了能量的投入推动着经济的发展,经济发展又会带来环境的破坏,要在经济发展的同时减少环境的污染程度,不能采取简单的末端治理方式,而应从能量投入的源头开始治理,为此,要采取清洁的生产方式,减少废物排放量,并把真正的废物进行资源化利用,确保系统的完备性,做到能量投入减量化,经济发展,高速化,环境污染低量化,由此,结合沱牌集团的计划项目,我们模拟了沱牌集团废物资源化利用的框架,并用具体实例进行分析。  相似文献   
99.
《Area》2001,33(1):77-106
Observations include:
Ian Livingstone, London: a sustainable city?, p.77
Michael Parkinson, Key challenges for European cities: achieving competitiveness, cohesion and sustainability, p.78
Chris Hamnett, London's housing, p.80
Sarah Curtis, Health in London, p.84
Martin Frost, London's transport—investing for sustainability, p.92
Chris Birks, Mike Owen and Brian Arkell, London's water resources: threat or opportunity, p.92
Sean D Beevers, David C Carslaw and Gary W Fuller, London's air quality: nitrogen dioxide and particles (PM10) in London's air—present and future, p.97
Adam D Read, Where there's muck there's brass—the 'cost' of London'swaste?, p.103  相似文献   
100.
戴惠新  王春秀 《矿物学报》2001,21(3):467-469
KN系列污水处理剂对不同污水采用多孔、层状非金属矿经活化复配而成,不仅对难降解有机废水具有良好的处理效果,也可用于易生物降解废水,并且价格低,相关工艺具有占地少、投资省、运转费用低的特点。所产生的污泥脱水性能好,并可无害化最终处理,不产生二次污染。  相似文献   
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