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71.
Insa Thale Sarah Maskri Lucie Grey Luca Matteo Todesca Prof. Dr. Thomas Budde Dr. Ivan Maisuls Prof. Dr. Cristian A. Strassert Prof. Dr. Oliver Koch Prof. Dr. Albrecht Schwab Prof. Dr. Bernhard Wünsch 《ChemMedChem》2023,18(2):e202200551
The Ca2+ activated K+ channel KCa3.1 is overexpressed in several human tumor cell lines, e. g. clear cell renal carcinoma, prostate cancer, non-small cell lung cancer. Highly aggressive cancer cells use this ion channel for key processes of the metastatic cascade such as migration, extravasation and invasion. Therefore, small molecules, which are able to image this KCa3.1 channel in vitro and in vivo represent valuable diagnostic and prognostic tool compounds. The [18F]fluoroethyltriazolyl substituted senicapoc was used as positron emission tomography (PET) tracer and showed promising properties for imaging of KCa3.1 channels in lung adenocarcinoma cells in mice. The novel senicapoc BODIPY conjugates with two F-atoms ( 9 a ) and with a F-atom and a methoxy moiety ( 9 b ) at the B-atom led to the characteristic punctate staining pattern resulting from labeling of single KCa3.1 channels in A549-3R cells. This punctate pattern was completely removed by preincubation with an excess of senicapoc confirming the high specificity of KCa3.1 labeling. Due to the methoxy moiety at the B-atom and the additional oxyethylene unit in the spacer, 9 b exhibits higher polarity, which improves solubility and handling without reduction of fluorescence quantum yield. Docking studies using a cryo-electron microscopy (EM) structure of the KCa3.1 channel confirmed the interaction of 9 a and 9 b with a binding pocket in the channel pore. 相似文献
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Fàbrega C Andreu T Güell F Prades JD Estradé S Rebled JM Peiró F Morante JR 《Nanotechnology》2011,22(23):235403
Highly ordered TiO(2) nanohole layers were synthesized by anodic oxidation of titanium foils using ethylene glycol and ammonium fluoride as the electrolyte. The effectiveness of different methods, namely annealing at 500?°C in NH(3) and in H(2) diluted in N(2), to incorporate nitrogen into TiO(2) and thus extend its photoelectrochemical (PEC) activity to the visible range was studied. The intra-gap levels introduced by both processes were identified by means of XPS and PL measurements. Water splitting experiments demonstrated that annealing in H(2) improved the photocatalytic activity of pure TiO(2), while annealing in ammonia led to a decrease in the PEC performance. 相似文献
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Jierong Yi Cristian De Gobba Leif H. Skibsted 《International Journal of Food Properties》2017,20(5):1129-1144
Grass carp skin pieces were homogenized in water and hydrolyzed by Alcalase®, collagenase, proteinase K, and/or trypsin at their optimum conditions. Samples were taken at various degrees of hydrolysis and were evaluated for antioxidant, antimicrobial, and angiotensin-converting enzyme inhibitory activities. Alcalase and collagenase completely hydrolyzed the skin with different rates, and released peptides with antioxidant and angiotensin-converting enzyme-inhibitory activity. These activities increased linearly with increasing degrees of hydrolysis. Subsequent incubation of the collagenase hydrolysates with trypsin slightly increased the antioxidant activity. Proteinase K, although only partially hydrolyzing the skin, also catalyzed the release of peptides with antioxidant and angiotensin-converting enzyme-inhibitory activities. These results show that skin by-products from grass carp can be a source of bioactive peptides produced by a one-step reaction. Such hydrolysates may be applied in food products to prolong shelf life and provide beneficial effects on blood pressure. 相似文献
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One continues the qualitative analysis started in Part I (F?ciu and Molinari in Acta Mech) concerning the thermomechanical characteristics of a steady, structured moving phase boundary in a shape memory alloy (SMA) by a quantitative investigation. The internal structure of these interphase layers is governed by a Maxwellian rate-type constitutive equation coupled or not with the Fourier heat conduction law. We consider as equilibrium stress–strain–temperature response function for the Maxwellian model an explicit piecewise linear thermoelastic relation for an SMA bar which can exist in the austenite phase A and in two variants of martensite M ±. Its thermal properties are built in agreement with experimental results on NiTi. This equilibrium relation has the atypical property that not only the derivative of the stress response function with respect to the strain changes its sign, but also the derivative with respect to the temperature. Considerable temperature variation is generated by impact-induced phase transformations due to the large amount of latent heat released (absorbed) inside the transition layer. One gets strong heating (cooling) across a compressive A→ M ? (expansive M ? → A) propagating interphase layer. A significant lower (larger) temperature than that at the front and Hugoniot back state is obtained inside an impact-induced M +→ M ? (M ?→ M +) interphase layer. The experimental finding of this phenomenon of temperature undershoot (overshoot) could be a valuable indication for the existence of an interphase layer. 相似文献
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Adsorption and surface chemistry in tribology 总被引:2,自引:0,他引:2
Adsorption on sliding surfaces and the chemical changes occurring within a few nanometers of the surface are key to the performance of lubricants and lubricant additives in the boundary lubrication regime. By means of the methods of modern surface science, these phenomena are beginning to be elucidated on a molecular level. This knowledge will be essential, both for the development of higher-performance lubricants, capable of high-temperature operation, as well as for the design of environmentally benign alternatives to the lubricant systems in current use. 相似文献
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