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991.
针对硫磺回收装置克劳斯二级反应器有机硫水解率较低的问题,采用新型共浸技术研发了中温有机硫水解催化剂。考察了催化剂的耐硫性能及温度对催化剂性能的影响。实验结果表明,在220~300℃的温度范围内,催化剂表现出较高的有机硫水解性能;且在H_2S、SO_2、CS_2体积分数变化的范围内,均优于现阶段二级反应器中装填的活性氧化铝催化剂。 相似文献
992.
针对石西油田低渗油藏强水敏性伤害储层,油井转注水初期,普遍存在注入压力高、注不进的实际问题,基于黏土矿物的防膨原理和现场防膨经验,为了提高XH-F3防膨剂的防膨效果,采用乙醇与注入水混配,其防膨率得到显著提高,满足了油田指标要求。静态实验结果表明,采用该防膨技术,岩心破碎率低、腐蚀率低,配伍性好。现场实验表明,注入该防膨型醇水配制的酸液,酸化后注入压力大大下降,注水量增加3~5倍,达到了防止黏土矿物膨胀、实现近井地带酸化解堵的目的。 相似文献
993.
Zixiang Wang Youheng Zheng Fengling Chen Xinong Xie Shiqiang Wu 《Petroleum Science and Technology》2018,36(2):148-153
The objective of this study is to provide biomarker geochemistry information on shale between sheet-like salts from Qianjiang Depression of the Jianghan salt lake facies Basin, and illustrate the depositional conditions, source organic matter input and maturation. 7 shale samples from Eq34-10 rhythmic were analysed with gas chromatography-mass spectrometry. The investigated biomarkers show that the shale oil are charactertized by an apperent odd-even preference of n-alkane, low Pr/Ph values and a high content of gammacerane and C30+ hopanes, maderate C21-/C21+ ratios, the high relative content of C27 5α(H), 14α(H), 17α(H)- steranes (20R), and an anomaly high C29 sterane ββ/(ββ + αα) value. These biomarker geochemistry characterizations suggested that the shale oils were derived from mixed aquatic organisms and land plants, and deposited in an anoxic and saline-hypersaline depositional environment. 相似文献
994.
During CO2 flooding, the crude oil is treated with CO2, and meanwhile it is displaced by CO2. Based on the two processes, the influence of pressure and CO2 content on the asphaltene precipitation and oil recovery efficiency are systematically investigated by indoor simulation experiment. With the increase of the pressure or CO2 content during CO2 treatment, the amount of asphaltene precipitation can be increased to a certain value. Correspondingly, the degrees of the changes of oil-water interface, the compositions of crude oil, and reservoir permeability are positively correlated with the amount of asphaltene precipitation. However, during the process, the oil recovery has an optimal value due to the combined action of asphaltene precipitation and the improvement of flow performance of the crude oil. These conclusions can provide a basis for high efficiency development of low permeability oil reservoirs by CO2 flooding. 相似文献
995.
Less than 10% of oil is usually recovered from liquid-rich shales and this leaves much room for improvement, while water injection into shale formation is virtually impossible because of the extremely low permeability of the formation matrix. Injecting carbon dioxide (CO2) into oil shale formations can potentially improve oil recovery. Furthermore, the large surface area in organicrich shale could permanently store CO2 without jeopardizing the formation integrity. This work is a mechanism study of evaluating the effectiveness of CO2-enhanced oil shale recovery and shale formation CO2 sequestration capacity using numerical simulation. Petrophysical and fluid properties similar to the Bakken Formation are used to set up the base model for simulation. Result shows that the CO2 injection could increase the oil recovery factor from 7.4% to 53%. In addition, petrophysical characteristics such as in situ stress changes and presence of a natural fracture network in the shale formation are proven to have impacts on subsurface CO2 flow. A response surface modeling approach was applied to investigate the interaction between parameters and generate a proxy model for optimizing oil recovery and CO2 injectivity. 相似文献
996.
本文阐述了实用型自动调谐的钛宝石激光器的设计,用Nd:YAG倍频的脉冲激光泵浦,在10Hz的重复频率下获得单脉冲最高输出能量为60mJ,效率为37.5%. 相似文献
997.
998.
为使激光诱导动态光栅产生在空间上可分辨的高效率衍射光,光栅介质必须足够薄以满足光栅条件,但动态光栅自衍射效率却又随介质厚度的增加而增加,我们提出用相位匹配的周期性薄光栅组可解决这一矛盾,并在实验上用周期性热效应光栅对理论进行了验证。 相似文献
999.
1000.
Bin He Dongsheng Wu 《IEEE transactions on bio-medical engineering》1997,44(7):529-538
A new approach is proposed to solve bioelectric inverse problems by employing the surface Laplacian of the bioelectrical potential. A theoretical investigation was conducted to test the feasibility of epicardial inverse imaging of cardiac electrical activity. A two-sphere homogeneous volume conductor model, where the inner sphere represents the epicardium and the outer sphere the body surface, was used. Radial and tangential current dipoles were used to approximate localized wavefronts propagating from the endocardium to the epicardium, and ectopic myocardial activities. The epicardial potential distribution was reconstructed from the body surface Laplacians with the aid of the Tikhonov zero-order regularization technique, which then was compared with the results obtained from the body surface potentials using the same regularization scheme. The two inverse solutions were compared qualitatively via visual inspection of the reconstructed epicardial potential maps, and quantitatively by examining relative errors and correlation coefficients between the “true” and the reconstructed epicardial potentials. Both qualitative and quantitative results indicate that the surface Laplacians play a positive role in improving the ill-posed nature of the bioelectric inverse problem, which would enhance one's capability of reconstructing important epicardial events such as extrema in the epicardial potential distribution. The present theoretical study suggests that the Laplacian-based inverse imaging technique may have important applications to epicardial inverse imaging and other bioelectric inverse imaging 相似文献