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31.
由于学科特性与教学要求,“软件工程”课程教学对实践性和系统性的要求极高。PBL教学模式作为一种自主式教学的新型模式,在教育领域受到广泛关注。文章基于PBL教学模式的特点及优势,结合“软件工程”课程教学改革趋势及教学实践中面临的主要困境,系统分析了PBL教学模式应用于“软件工程”课程教学的途径,以期为促进“软件工程”的课程教学改革及教学质量提高提供参考及借鉴。 相似文献
32.
Being the main driver of innovation in the automotive industry, vehicle software calls for more efficient tools for its development. Safety-critical applications are predominantly written respecting the AUTOSAR standard, where tasks comprise code-fragments called runnables, and deployed on multi-core architectures. However, task parallelization introduces a substantial number of idle intervals, as runnables have to be mapped and scheduled at design-time without violating data dependencies. In parallelized event-triggered tasks, these intervals are utilized by migrating runnables from the interrupted time-triggered tasks. We propose to also migrate runnables from consecutively scheduled tasks and additionally, to maximize their number using DPM-aware application scheduling. 相似文献
33.
Apichaya Theampetch Chaiwat Prapainainar Sabaithip Tungkamani Phavanee Narataruksa Thana Sornchamni Líney Árnadóttir Goran N. Jovanovic 《International Journal of Hydrogen Energy》2021,46(48):24721-24741
Fuels production from syngas via Fischer Tropsch synthesis (FTs) is an alternative technology for clean energy production. The microkinetic model is a promising approach for gaining insight into FTs activity. In this study, a systematic microkinetic model was proposed to develop a process for cobalt-catalyzed FTs. All possible elementary reactions based on the carbide mechanism and characteristics of catalyst sites were considered in the kinetic model. The effects of the reaction rate constant, reaction pathways, and H2 to CO ratio were represented by a kinetic parameter, reaction path, and operating parameter, respectively. The model could accurately predict product distribution trends, with an R2 value and mean absolute relative residuals percentage of 0.91–0.93 and 5–43%, respectively, in comparison with experimental data. Hydrogen utilization was predicted and analyzed. High model accuracy was achieved, with a 10?10–10?3% error in the material balance. 相似文献
34.
Seda Karaboğa 《International Journal of Hydrogen Energy》2021,46(34):17763-17775
It reports the preparation and characterization of tungsten(VI) oxide supported rhodium(0) nanoparticles (Rh0/WO3 NPs) being used as catalysts in releasing H2 from dimethylamine borane (DMAB). The reducible nature of WO3 plays a significant role in the catalytic efficiency of rhodium(0) nanoparticles in the dehydrogenation of DMAB. The Rh0/WO3 NPs were in-situ generated from the reduction of Rh2+ ions on the surface of WO3 during the catalytic dehydrogenation of dimethylamine borane in toluene and isolated from the reaction solution after the dehydrogenation to be characterized by using SEM, TEM, XPS, ATR-IR and XRD. The results reveal the formation of Rh0 NPs with a mean particle size of 1.92 ± 0.34 nm dispersed on the surface of tungsten(VI) oxide. Rh0/WO3 NPs are found to be very active catalyst releasing 1.0 equiv. H2 per mole of dimethylamine borane under ambient conditions. Among the various WO3 supported Rh0 NPs with different metal loadings, the sample with 0.1% wt. Rh provide the record catalytic activity (TOF = 2816 h?1) which is one of the highest value ever reported for rhodium-based catalysts in H2 generation from DMAB at 60.0 ± 0.5 °C. Rh0/WO3 NPs were also reusable catalyst in dehydrogenation of DMAB retaining 55% of their initial catalytic activity in the 3rd run of the dehydrogenation reaction. Control experiments were performed at various catalyst concentrations and temperatures to investigate the kinetics of dehydrogenation and to calculate the activation parameters for the reaction. 相似文献
35.
《Advanced Powder Technology》2022,33(11):103777
In this study the constructional modification of Graphitic carbon nitride nanosheet (GCN-ns) has been made with the aid of ZnCr layered double hydroxide (ZC-LDH) in a unique 2D-2D structure to enhance its visible light absorption. Optical and morphological study presents successful incorporation of ZC-LDH on the surface of GCN-ns. Through adjusting of GCN-ns by ZC-LDH lower recombination rate of e?/h+ pairs, longer lifetimes and an increase in contamination reduction was brought out. The binary nanocomposite was employed to effectively degrade Rhodamine B under UV/vis light irradiation. The improvement in photocatalytic abilities was proven to be related to in situ self-production of H2O2 on GCN-ns/ZC-LDH surface by Xe light irradiation which in return accounts for additional hydroxide radical generation. Radical quenching experiments specified the main active species involved while the consequent step-scheme (S-scheme) charge transfer mechanism was proposed. 相似文献
36.
《International Journal of Hydrogen Energy》2022,47(12):8118-8129
The reduction of wüstite (FeO) is the most difficult step in the multi-step of iron oxides, and the basic characteristics of the hydrogen reduction of FeO are particularly important for the low-carbon development in metallurgy. In this work, the hydrogen reduction of pure FeO pellets was studied numerically by a 2D mesoscale method, which was further developed based on the lattice gas model. The method employed the directional probability and reaction probability to describe gas diffusion and reaction, respectively. The method was firstly validated by comparing with experiments reported by Usui et al. Then, the influence of reaction temperature, particle size, and porosity on the hydrogen reduction of FeO was conducted. The results demonstrated that the reaction rate increased with increasing temperature, increasing porosity, and decreasing particle size. The reaction mechanism depended on FeO pellet radius and porosity, it was boundary reaction at smaller radius (80 μm) or smaller porosity (0.210). 相似文献
37.
矿井通风网络优化软件及其应用 总被引:6,自引:2,他引:6
介绍了通风网络优化软件的数学模型及其特点。软件在安徽某矿对通风系统改造方案进行优化和现场应用实践的结果表明,该矿按照软件优化出的最优方案实施后,井下的通风效果得到了显著改善。显示该软件先进可靠,在Windows操作平台上运行具有较好可视化效果。 相似文献
38.
本文主要介绍计算机在尖山铁矿基建管理系统的应用实践。该系统可取代繁琐的人工作业,可以为各级领导及时提供真实可靠的信息,较有力地服务于基建管理工作。本文将详细论述这一软件系统是怎样将数据管理、制订计划、统计报表、查询有机地结合在一起的。 相似文献
39.
分析了非均匀崩落矿岩散体在放矿过程中的流动特点,通过相似模拟实验,得出了非均匀矿岩散体在放矿过程中,放出矿石贫化的主要原因是放出口矿岩界面漏斗破裂,而不是矿岩颗粒在下移过程中的相互掺杂;在覆岩废石颗粒粒径大于或与矿石颗粒粒径接近时,采用见到废石漏斗破裂便停止放出放矿方式,可取得较好的放矿指标;当覆岩废石颗粒粒径小于矿石时,由于细小废石颗粒的穿流作用,使放出矿石过早地产生贫化,为了提高矿石回收率,就应该适当地增加废石的混入量,按照低贫化放矿方式直到见到矿岩界面正常到达出矿水平才停止放矿。采用低贫化放矿方式,低的矿石贫化率同样可以达到较高的矿石回收率。 相似文献
40.