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991.
目前油田常规注水开发难度不断增加,应用注CO2气驱技术能够有效解决注水困难等问题,提高了原油采收率。在室内实验研究的基础上,应用数值模拟技术优化了注气方式及注气时机;分析了油藏地质参数对注CO2气驱提高采收率的影响。研究表明:水气交替注入方式更优;非均质性越强,开发效果越差;油藏渗透率越大、含油饱和度越高、原油粘度越低,注CO2驱油效果越好。 相似文献
992.
Progress in the use of ATR-IR spectroscopy to improve the understanding of liquid-phase heterogeneous catalytic reactions
is illustrated using the example of the oxidation of benzyl alcohol over Pd/Al2O3 and Bi–Pd/Al2O3. The in situ studies performed in both batch and continuous reactor cells provide rich information on the reaction pathway
and important facets of the mechanism, such as the nature of active Pd sites and the effect of the Bi-promoter. The combination
of CO site blocking prior to reaction and isotopic labeling suggests that alcohol dehydrogenation occurs uniformly over Pd
nanoparticles, but only selected sites may allow desorption of the product benzaldehyde thus providing the required selectivity.
Promotion of Pd/Al2O3 using bismuth produces infrared spectra free of adsorbed CO. This information demonstrates that Bi is deposited on selected
adsorption sites (terraces rather than defects) and simultaneously confirms that open terraces favor product decomposition.
Experiments performed in the continuous reactor cell using different catalyst film thickness show that reactions can be studied
under kinetic or mass transfer limited conditions depending on catalyst film thickness. This allowed to study the alcohol
oxidation under conditions of oxygen diffusion limitation, which are preferably applied in praxis in order to prevent catalyst
deactivation by over-oxidation. 相似文献
993.
介绍了常温精脱硫技术和脱氢技术在CO2汽提法尿素生产中的运行效果。通过增设常温精脱硫装置不仅有效地保护了脱氢催化剂,而且降低了尿素设备的腐蚀;通过增加脱氢技术不仅提高了尿素转化率,更重要的是避免了形成爆炸性气体,同时减轻了低压系统的负担,起到了安全、节能的作用。 相似文献
994.
一氧化碳变换系统存在问题及改造措施 总被引:3,自引:0,他引:3
介绍中原大化分公司500kt/a甲醇项目变换系统流程及变换技术特点,分析系统运行中存在的问题及危害,提出了改造措施。实施后从根本上消除了隐患,保证了变换系统的安全稳定运行。 相似文献
995.
996.
Serge Laplante Nathalie Souchet Piotr Bryl 《European Journal of Lipid Science and Technology》2009,111(2):135-141
Among the fat fish species available from Eastern Quebec (Canada), whole Atlantic mackerel (Scomber scombrus) and herring (Clupea harengus) represent abundant fishery resources which are currently under‐utilized. They have relatively high contents of oil and coenzyme Q10 (CoQ10) in their tissues, which could be valuable for nutraceutical applications. Therefore, two low‐temperature extraction processes were compared for the recovery of oil and CoQ10 from these resources, such as enzymatic hydrolysis using Protamex? and supercritical CO2 (SCO2) using fish lyophilizates. The results revealed that highest yields of oil and CoQ10 were obtained using the enzymatic hydrolysis process with mackerel. Whatever the process used, CoQ10 concentrations were higher in herring oil, due mainly to a more selective extraction of CoQ10 over that of the oil. The highest CoQ10 recovery rates (extraction efficiencies) were obtained using the enzymatic hydrolysis process with both types of fish, but also the SCO2 process with herring under some conditions. For mackerel, the lower CoQ10 recovery rates obtained from the SCO2 process were explained by its more important matrix effect. An economic assessment of both processes revealed that the enzymatic hydrolysis extraction process would be the most promising for up‐scaling the recovery of oil and CoQ10 from these resources. 相似文献
997.
制备了碳化铁和钾掺杂碳化钼催化剂并对其CO加氢合成低碳混合醇性能进行了考察.结果表明当只有β-碳化钼存在时,产物主要是烃类以及微量的醇.经过钾改性后,β-碳化钼催化剂上产物低碳醇含鼍增加;而同时被碳化铁和钾改性后,低碳醇的含量进一步增加,并且高级醇(C_(2+)OH)收率町达到0.14 g/(mL·h).β-碳化钼催化剂上醇烃产物均符合线性Anderson-Schuhz-Mory(A-S-F)分布曲线,而钾改性β-碳化钼以及钾和碳化铁改性的催化剂上醇产物为独特的甲醇负偏离A-SF分布.这表明钾和碳化铁的加入有效促进了C_1OH到C_2OH的链增长步骤.从而有利于C_(2+)OH高级醇的生成. 相似文献
998.
酮基布洛芬生产工艺研究与改进 总被引:1,自引:0,他引:1
分析了酮基布洛芬原生产工艺,重点对甲基化反应和酰化-傅克反应过程进行了研究与改进:以高选择性单甲基化试剂(CH_3O)_2CO代替(CH_3O)_2SO_2,实现了单基化反应;傅克反应过程用苯-SOCl_2共沸带出酰氯物中的SOCl_2,避免了副产物二苯亚砜的生成.工艺改进后,总收率比原有工艺的总收率提高了28.2%以上. 相似文献
999.
Hassan Hassanzadeh Mehran Pooladi‐Darvish David W. Keith 《American Institute of Chemical Engineers》2009,55(2):475-485
Carbon dioxide injection into deep saline aquifers is an important option for managing CO2 emissions. Injected CO2 dissolves into formation brines from above, increasing brine density and creating an unstable hydrodynamic state favorable for natural convection. Long‐term buoyancy‐driven flow of high‐density CO2‐saturated brine leads to faster trapping through improved dissolution and can reduce the risk of CO2 leakage from storage sites. We investigate the role of natural flow of aquifers and associated dispersion on the onset of convection. A linear stability analysis of a transient concentration field in a laterally infinite, horizontal, and saturated porous layer with steady horizontal flow is presented. The layer is subjected to a sudden rise in CO2 concentration from the top and is closed from the bottom. Solution of the stability equations is obtained using a Galerkin technique and the resulting equations are integrated numerically. We found simple scaling relationships that follow tDc~60(1 + PeT)Ra‐2 for the onset time of convection and a~0.05Ra/(1 + PeT) for the wavenumber of the initial instabilities. Results reveal that transverse dispersion increases the time to onset of convection for the entire range of Ra. Furthermore, transverse dispersion decreases the critical wavenumber of the instabilities. These results facilitate screening candidate sites for geological CO2 storage. © 2008 American Institute of Chemical Engineers AIChE J, 2009 相似文献
1000.
分析了裂解气中CO2含量高对乙烯装置的影响和CO2含量高的原因,探讨了钠离子的来源及其在裂解反应中促进生成CO2的机理,提出了消除炉管中残留钠离子对裂解炉影响的方法。 相似文献