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A. A. Berdychenko B. S. Zlobin L. B. Pervukhin A. A. Shtertser 《Combustion, Explosion, and Shock Waves》2003,39(2):232-239
Processes that occur in the welding gap during explosive welding are analyzed. It is shown that metal particles flying out into the gap due to the jetformation effect can ignite in shockcompressed air. For most metals, the energy released thereby is small and has no significant influence on weld formation. In titanium welding on large areas, surface sections located far from the place of detonation initiation, which experience a longterm action of a hot air flow, can dissolve a large amount of oxygen and nitrogen. If particles from these sections enter the gap, it can lead to chemical reactions with formation of TiO2 and TiN by the mechanism of internal combustion. The energy released in the gap per unit area is commensurable with and even greater than the kinetic energy of the accelerated (flyer) plate. Local bulging and rupture of metal observed in practice can be explained by ignition and combustion of gassaturated titanium particles in the welding gap. 相似文献
155.
Interaction of impact shock waves that could detonate an explosive (Composition B) confined in a thin-walled container impacted by a cone-nosed projectile is numerically studied, based on the Forest Fire explosive reaction rate model. The normal impact on the container by a small projectile with a conical nose is considered. Depending on the cone angle of the nose part of the projectile, the zone of interaction of initiating shock waves can be remote from the central axis of the impact. The off-the-central-axis detonation is interpreted from the viewpoint of different interaction modes in the explosive container, which are reflected from the cassette wall, change their directions, and superimpose onto each other, leading to explosive detonation. 相似文献
156.
高聚物黏结炸药的力学性能研究进展 总被引:5,自引:0,他引:5
从材料的力学行为特性、实验方法、本构模型和强度理论4个方面对高聚物黏结炸药(PBX)的力学性能特征进行了归纳和评述。指出应变率和温度对材料应力状况的影响及动态力学性能分析是目前PBX研究的热点和难点。认为可以借鉴研究混凝土和高聚物的一些方法来建立PBX的本构模型和失效准则。指出选择和改进现有测试技术时,须考虑PBX的含能敏感性、大变形等特性。对PBX力学性能的理论研究、实验技术及数值模拟等方面需要开展的工作提出了一些看法。认为复杂环境下的力学响应和细观建模模拟应是今后研究的重点方向。附参考文献93篇。 相似文献
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采用高速扫描相机和楔形炸药构型,对新型高能钝感炸药JBO-9X的冲击起爆过程进行了实验研究;采用LS-DYNA软件对实验结果进行了数值模拟验证。结果表明,在6.9GPa的入射冲击压力下,JBO-9X炸药的冲击转爆轰时间为1.5μs,冲击到爆轰的距离为7.9mm;当冲击波刚进入炸药时,炸药发生化学反应的比例(λ)为0.2,随着冲击波进入炸药的距离增加,受试炸药中发生化学反应的比例逐步增加。在实验条件下,入射冲击波压力为6.85GPa时,JBO-9X炸药的冲击到爆轰距离为8.0mm。化学反应比例随冲击波进入炸药距离的增长曲线与实验基本相同。 相似文献
159.
FOX-7和RDX基含铝炸药的冲击起爆特性 总被引:1,自引:0,他引:1
为研究FOX-7和RDX基含铝炸药的冲击起爆特性,对其进行了冲击波感度试验和冲击起爆试验,结合冲击波在铝隔板中的衰减特性,确定了FOX-7和RDX基含铝炸药的临界隔板值和临界起爆压力,并通过锰铜压阻传感器记录了起爆至稳定爆轰过程压力历程的变化。结果表明,以Φ40mm×50mm的JH-14为主发装药时,FOX-7和RDX基含铝炸药临界隔板值分别为37.51和34.51mm,对应的临界起爆压力为10.91和11.94GPa;起爆压力为11.58GPa时,FOX-7炸药的到爆轰距离为25.49~30.46mm,稳定爆轰后的爆轰压力为27.68GPa,爆轰速度为8 063m/s;起爆压力为14.18GPa时,RDX基含铝炸药的到爆轰距离为17.27~23.53mm,稳定爆轰后的爆轰压力为17.16GPa,爆轰速度为6 261m/s。 相似文献
160.
Engineered Biomolecular Recognition of RDX by Using a Thermostable Alcohol Dehydrogenase as a Protein Scaffold 下载免费PDF全文
Dr. Beyza Bulutoglu Dr. Jennifer Haghpanah Prof. Elliot Campbell Prof. Scott Banta 《Chembiochem : a European journal of chemical biology》2018,19(3):247-255
There are many biotechnology applications that would benefit from simple, stable proteins with engineered biomolecular recognition. Here, we explored the hypothesis that a thermostable alcohol dehydrogenase (AdhD from Pyrococcus furiosus) could be engineered to bind a small molecule instead of a cofactor or molecules involved in the catalytic transition state. We chose the explosive molecule 1,3,5‐trinitro‐1,3,5‐triazine (royal demolition explosive, RDX) as a proof‐of‐concept. Its low solubility in water was exploited for immobilization for biopanning by using ribosome display. Docking simulations were used to identify two potential binding sites in AdhD, and a randomized library focused on tyrosine or serine mutations was used to determine that RDX was binding in the substrate binding pocket of the enzyme. A fully randomized binding pocket library was selected, and affinity maturation by error‐prone PCR led to the identification of a mutant (EP‐16) that gained the ability to bind RDX with an affinity of (73±11) μm . These results underscore the way in which thermostable enzymes can be useful scaffolds for expanding the biomolecular recognition toolbox. 相似文献