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151.
152.
The usability of hydrogen and also carbon containing fuels is one of the important advantages of solid oxide fuel cells (SOFCs), which opens the possibility to use fuels derived from conventional sources such as natural gas and from renewable sources such as biogas. Impurities like sulfur compounds are critical in this respect. State-of-the-art Ni/YSZ SOFC anodes suffer from being rather sensitive towards sulfur impurities. In the current study, anode supported SOFCs with Ni/YSZ or Ni/ScYSZ anodes were exposed to H2S in the ppm range both for short periods of 24 h and for a few hundred hours. In a fuel containing significant shares of methane, the reforming activities of the Ni/YSZ and Ni/ScYSZ anodes were severely poisoned already at low H2S concentrations of ∼2 ppm H2S. The poisoning effect on the cell voltage was reversible only to a certain degree after exposure of 500 h in the state-of-the-art cell, due to a loss of percolation of Ni particles in the Ni/YSZ anode layers closest to the electrolyte. Using SOFCs with Ni/ScYSZ anodes improved the H2S tolerance considerably, even at larger H2S concentrations of 10 and 20 ppm over a few hundred hours.  相似文献   
153.
Reports an error in "Difference rather than delay in development of elementary visuomotor processes in children born preterm without cerebral palsy: A quasi-longitudinal study" by Koenraad Van Braeckel, Phillipa R. Butcher, Reint H. Geuze, Maritje A. J. van Dujin, A. F. Bos and Anke Bourma (Neuropsychology, 2010[Jan], Vol 24[1], 90-100). In the current article the names of authors Marijtje A. J. van Duijn and Anke Bouma were misspelled as Maritje A. J. van Dujin and Anke Bourma, respectively. The online versions of this article have been corrected. (The following abstract of the original article appeared in record 2010-00119-012.) Follow-up studies of preterm children without serious neonatal medical complications have consistently found poor visuomotor and visuospatial skills. In the first round of current follow-up study, we found a deficit in elementary visuomotor processes in preterm children without Cerebral Palsy (CP). To determine whether the development of these processes was delayed or different, we carried out a quasi-longitudinal study in which kinematic characteristics of pointing movements in 7- to 11-year-old preterm born children without CP and in an age-matched full-term group were analyzed. Multi-level analysis suggested a difference rather than a delay in the preterm born group: we found a regression around 8 years of age in the control but not in the preterm group. To our knowledge, this study is the first to provide longitudinal data confirming this regression in the development of movement control in typically developing children. Our results are also consistent in suggesting that elementary visuomotor processes are less efficient in preterm born children without CP: their movements were either slower or less accurate. While these differences were subtle, they persisted until 11 years of age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
154.
This work aims to explore zirconium as a possible dopant to promote thermoelectric performance in bulk ZnO-based materials, both within the single-doping concept and on simultaneous co-doping with aluminum. At 1100–1223 K mixed-doped samples demonstrated around ~2.3 times increase in ZT as compared to single-doped materials, reaching ~0.12. The simultaneous presence of aluminum and zirconium imposes a synergistic effect on electrical properties provided by their mutual effects on the solubility in ZnO crystal lattice, while also allowing a moderate decrease of the thermal conductivity due to phonon scattering effects. At 1173 K the power factor of mixed-doped Zn0.994Al0.003Zr0.003O was 2.2–2.5 times higher than for single-doped materials. Stability tests of the prepared materials under prospective operation conditions indicated that the gradual increase in both resistivity and Seebeck coefficient in mixed-doped compositions with time may partially compensate each other to maintain a relatively high power factor.  相似文献   
155.
Tunable solvent systems provide optimal reaction conditions for homogeneous catalysis as well as appropriate conditions for separating the product from the catalyst via temperature switches. Two tunable solvent systems are presented based on different thermodynamic concepts, namely thermomorphic multicomponent solvent systems and dispersions of immiscible liquids, stabilized by nonionic surfactants as microemulsions. Both systems were applied for the regioselective hydroformylation of the model substrate 1‐dodecene with a Rhodium/ligand catalyst system. The accessibility of the catalyst for the reactants was compared between the molecularly dispersed mixtures and the colloidally dispersed microemulsion systems which are heterogeneous on the microscopic level.  相似文献   
156.
Molecular imaging of pathologic lesions can improve efficient detection of cancer and cardiovascular diseases. A shared pathophysiological feature is angiogenesis, the formation of new blood vessels. Endoglin (CD105) is a coreceptor for ligands of the Transforming Growth Factor-β (TGF-β) family and is highly expressed on angiogenic endothelial cells. Therefore, endoglin-based imaging has been explored to visualize lesions of the aforementioned diseases. This systematic review highlights the progress in endoglin-based imaging of cancer, atherosclerosis, myocardial infarction, and aortic aneurysm, focusing on positron emission tomography (PET), single-photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), near-infrared fluorescence (NIRF) imaging, and ultrasound imaging. PubMed was searched combining the following subjects and their respective synonyms or relevant subterms: “Endoglin”, “Imaging/Image-guided surgery”. In total, 59 papers were found eligible to be included: 58 reporting about preclinical animal or in vitro models and one ex vivo study in human organs. In addition to exact data extraction of imaging modality type, tumor or cardiovascular disease model, and tracer (class), outcomes were described via a narrative synthesis. Collectively, the data identify endoglin as a suitable target for intraoperative and diagnostic imaging of the neovasculature in tumors, whereas for cardiovascular diseases, the evidence remains scarce but promising.  相似文献   
157.
Antimicrobial resistance is a looming health crisis, and it is becoming increasingly clear that organic chemistry alone is not sufficient to continue to provide the world with novel and effective antibiotics. Recently there has been an increased number of reports describing promising antimicrobial properties of metal-containing compounds. Platinum complexes are well known in the field of inorganic medicinal chemistry for their tremendous success as anticancer agents. Here we report on the promising antibacterial properties of platinum cyclooctadiene (COD) complexes. Amongst the 15 compounds studied, the simplest compounds Pt(COD)X2 (X=Cl, I, Pt1 and Pt2 ) showed excellent activity against a panel of Gram-positive bacteria including vancomycin and methicillin resistant Staphylococcus aureus. Additionally, the lead compounds show no toxicity against mammalian cells or haemolytic properties at the highest tested concentrations, indicating that the observed activity is specific against bacteria. Finally, these compounds showed no toxicity against Galleria mellonella at the highest measured concentrations. However, preliminary efficacy studies in the same animal model found no decrease in bacterial load upon treatment with Pt1 and Pt2 . Serum exchange studies suggest that these compounds exhibit high serum binding which reduces their bioavailability in vivo, mandating alternative administration routes such as e. g. topical application.  相似文献   
158.
Objective: Coagulation and fibrinolysis are interrelated with the expression of vascular endothelial growth factor (VEGF), which frequently is increased in axial spondyloarthritis (axSpA). We tested whether (i) α2-antiplasmin (A2AP) Arg6Trp, (ii) fibrinogen, factor XIII A-subunit or B-subunit genotypes are associated with VEGF levels and assessed whether the known association between elevated VEGF and radiographic spinal progression in axSpA depends on genetic background. Methods: One hundred and eighty-six axSpA patients from the German Spondyloarthritis Inception Cohort were genotyped, characterized for VEGF levels, and statistically analyzed. The association between VEGF and radiographic spinal progression was assessed in dependence on genetic background in stratified analyses. Results: A2AP 6Trp carriage was associated with VEGF elevation (OR: 2.37, 95% CI: 1.06–5.29) and VEGF levels (6Trp, 455 ± 334 pg/mL; 6Arg/Arg, 373 ± 293 pg/mL; p < 0.008). Association between elevated VEGF and radiographic spinal progression in axSpA (OR: 3.11, 95% CI: 1.02–8.82) depended remarkably on the fibrinogen (FGA) genotype. When considering axSpA patients with elevated VEGF, in FGA rs6050A>G wild types, 42.1% of patients (8 of 19) progressed, while in G-allele carriers, no radiographic progression happened (0 of 13) (p < 0.04). Conclusions: The A2AP Arg6Trp genotype seems to influence VEGF levels in axSpA. The predictive value of VEGF elevations in respect of radiographic spinal progression in axSpA depends on FGA genotypes.  相似文献   
159.
Mono- and bifunctional hybrid core-shell particles were used for enzyme immobilization. Ideal conditions for enzyme immobilization were evaluated based on monofunctional poly(2-dimethylamino)ethyl methacrylate-modified particles. Then, the obtained results were transferred to a bifunctional Janus particle system, which should simultaneously enable enzyme immobilization, switchable separation, and reuse of the enzyme. Finally, application of the system was exemplarily demonstrated by multiple discoloration of textile industry process water with laccase and a cost estimation is presented.  相似文献   
160.
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