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1.
The performance of Microbial electrolysis cell (MEC) is affected by several operating conditions. Therefore, in the present study, an optimization study was done to determine the working efficiency of MEC in terms of COD (chemical oxygen demand) removal, hydrogen and current generation. Optimization was carried out using a quadratic mathematical model of response surface methodology (RSM). Thirteen sets of experimental runs were performed to optimize the applied voltage and hydraulic retention time (HRT) of single chambered batch fed MEC operated with dairy industry wastewater. The operating conditions (i.e) an applied voltage of 0.8 V and HRT of 2 days that showed a maximum COD removal response was chosen for further studies. The MEC operated at optimized condition (HRT- 2 days and applied voltage- 0.8 V) showed a COD removal efficiency of 95 ± 2%, hydrogen generation of 32 ± 5 mL/L/d, Power density of 152 mW/cm2 and current generation of 19 mA. The results of the study implied that RSM, with its high degree of accuracy can be a reliable tool for optimizing the process of wastewater treatment. Also, dairy industry wastewater can be considered to be a potential source to generate hydrogen and energy through MEC at short HRT.  相似文献   
2.
Garzan oil field is located at the south east of Turkey. It is a mature oil field and the reservoir is fractured carbonate reservoir. After producing about 1% original oil in place (OOIP) reservoir pressure started to decline. Waterflooding was started in order to support reservoir pressure and also to enhance oil production in 1960. Waterflooding improved the oil recovery but after years of flooding water breakthrough at the production wells was observed. This increased the water/oil ratio at the production wells. In order to enhance oil recovery again different techniques were investigated. Chemical enhanced oil recovery (EOR) methods are gaining attention all over the world for oil recovery. Surfactant injection is an effective way for interfacial tension (IFT) reduction and wettability reversal. In this study, 31 different types of chemicals were studied to specify the effects on oil production. This paper presents solubility of surfactants in brine, IFT and contact angle measurements, imbibition tests, and lastly core flooding experiments. Most of the chemicals were incompatible with Garzan formation water, which has high divalent ion concentration. In this case, the usage of 2-propanol as co-surfactant yielded successful results for stability of the selected chemical solutions. The results of the wettability test indicated that both tested cationic and anionic surfactants altered the wettability of the carbonate rock from oil-wet to intermediate-wet. The maximum oil recovery by imbibition test was reached when core was exposed 1-ethly ionic liquid after imbibition in formation water. Also, after core flooding test, it is concluded that considerable amount of oil can be recovered from Garzan reservoir by waterflooding alone if adverse effects of natural fractures could be eliminated.  相似文献   
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4.
The importance of data processing and storage to colleges and universities is increasing day by day. However, many colleg- es and universities are still at a low level in the process of data recovery and application reduction, and its RPO and RTO indicators need to be improved by adopting the dual active technology architecture. Taking the Guizhou Vocational Technology Institute as an example, this paper focuses on the analysis of the architecture of the double active data center, aiming at the actual situation of the college, and gradually realizes multiple disaster recovery level of data level, application level and business level.  相似文献   
5.
针对目前蒸汽吞吐产量预测模型假设条件简单、普适性差等问题,一般采用测试法和类比法综合确定海上稠油油田蒸汽吞吐初期产量。由于目前海上油田通常只开展常规测试,无法直接获得热采开发初期产量。笔者提出海上稠油油田蒸汽吞吐初期产量确定新方法,建立蒸汽吞吐相对于常规开发的初期产量倍数预测模型,通过蒸汽吞吐产量倍数,将常规测试确定的产量转化为蒸汽吞吐产量。研究表明,蒸汽吞吐初期产量倍数主要受储集层渗透率、原油黏度、注入强度、蒸汽干度等因素影响,利用正交试验设计和多元回归等方法,建立海上稠油油田蒸汽吞吐初期产量倍数与油藏地质参数及注入参数之间的非线性预测模型,该模型经实际生产数据验证,预测误差小于5%,可靠性高,能够为海上稠油油田蒸汽吞吐初期产量的确定提供依据。  相似文献   
6.
基于云铜西南铜业分公司贵金属工艺流程构建了金属回收率模型。该模型以内部付出率、内部损失率、外部回收率、单位投入量、循环次数为影响因子,分析在一定工艺效果前提下各参数与末端工艺段回收率的关系。通过对模型的计算分析,确定了单一因子变化、双因子变化对回收率的影响趋势,以及内部付出率、内部损失率、外部回收率细微变化时对回收率的贡献量;并确定了3个参数间的影响大小顺序。同时介绍了该模型在实际生产中的应用情况。  相似文献   
7.
This study evaluates the geothermal history of Palaeozoic sedimentary rocks from the easternmost part of the Variscan external zone in the NE Czech Republic. The objective was to investigate the geothermal history of pre‐Variscan Palaeozoic carbonates in the study area, and to assess its relationship with that of the overlying Variscan flysch. In the study area, the Palaeozoic succession occurs at the surface or is overlain by Miocene sediments of the Carpathian Foredeep. Palaeozoic nappes and the main Variscan overthrust have been documented in the subsurface at the deep Pot?tát‐1borehole. Vitrinite reflectance measurements on 38 samples from the Pot?tát‐1 well and 19 samples from nearby surface outcrops and shallow boreholes were available. A 2D thermal model was created using PetroMod and the thermal maturity evolution was modelled by EASY%Ro. The thermal model was constructed based on interpretations of two NW‐SE seismic profiles (lines 5/83 and 5/84) oriented perpendicular to the main Variscan thrusts. The results were calibrated using measured vitrinite reflectance and were adjusted with 1D models from three shallow boreholes. At the Pot?tát‐1 borehole, modelled maximum palaeo‐temperatures of the Variscan flysch (Moravice Formation) ranged from 310°C at a depth of 7.3 km (the top of the preserved succession) to 395°C at the base of the succession, resulting in thermal maturities of >4%Rr. Peak maturation occurred prior to the end of Variscan thrusting. Modelling suggests that the basal heat flow for these thrust units reached a maximum value of 63 mW/m2 at 325 Ma. In addition, the modelling suggests that the maturity of the Palaeozoic carbonates was controlled by the thickness of the overlying Variscan flysch nappes. Maximum palaeo‐temperatures for the Palaeozoic carbonates ranged from 265°C at the top of the interval (at a depth of 7.1 km) to 290°C at the base, resulting in a maturity of 3.8 to >4%Rr which is within the dry gas window. The study suggests that basal heat flows in the original (pre‐thrust) Early Carboniferous sedimentary basin were slightly higher than those in the post‐thrust location for the Variscan flysch nappes. This should be taken into account when evaluating the petroleum system in the South Moravian oil province (SW Czech Republic) where a complete sedimentary sequence has not been preserved.  相似文献   
8.
An experimental study was performed to investigate the impact of low salinity water on wettability alteration in carbonate core samples from southern Iranian reservoirs by spontaneous imbibition. In this paper, the effect of temperature, salinity, permeability and connate water were investigated by comparing the produced hydrocarbon curves. Contact angle measurements were taken to confirm the alteration of surface wettability of porous media. Oil recovery was enhanced by increasing the dilution ratio of sea water, and there existed an optimum dilution ratio at which the highest oil recovery was achieved. In addition, temperature had a very significant impact on oil recovery from carbonate rocks. Furthermore, oil recovery from a spontaneous imbibition process was directly proportional to the permeability of the core samples. The presence of connate water saturation inside the porous media facilitated oil production significantly. Also, the oil recovery from porous media was highly dependent on ion repulsion/attraction activity of the rock surface which directly impacts on the wettability conditions. Finally, the highest ion attraction percentage was measured for sodium while there was no significant change in pH for all experiments.  相似文献   
9.
针对氧化吸收工艺应用于天然气净化厂Claus尾气减排的情况,利用VMGSim软件模拟了该工艺脱除Claus尾气中SO_2并返回二级Claus工艺的过程,阐明了不同的SO_2返回位置对硫回收率及主燃烧炉温度的影响,并提出了应对措施,可为氧化吸收工艺在天然气净化厂的应用提供重要参考。  相似文献   
10.
中贵线乙烷回收工程模拟计算研究   总被引:1,自引:1,他引:0  
在国内大型凝析气田中,发现原料气中含有丰富的乙烷,为加强乙烷资源的有效利用,实现天然气产业效益最大化,开展了中贵线乙烷回收工程可行性研究。该项目采用ASPEN HYSYS模拟软件,对膨胀机制冷+尾气再循环脱甲烷塔双回流工艺进行研究,并对该工艺的流程特性进行分析考察了膨胀后压力、低温分离器温度、膨胀气流比例、原料气组成中CO_2与C_2H_6含量及原料气压力等因素的变化,以及对装置性能包括收率、动力消耗、天然气消耗以及年收益的影响。  相似文献   
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