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991.
Simon Braumann Wibke Schumacher Nam Gyu Im Felix Sebastian Nettersheim Dennis Mehrkens Senai Bokredenghel Alexander Hof Richard Julius Nies Christoph Adler Holger Winkels Ralph Knll Bruce A. Freeman Volker Rudolph Anna Klinke Matti Adam Stephan Baldus Martin Mollenhauer Simon Geißen 《International journal of molecular sciences》2021,22(16)
Nitro-oleic acid (NO2-OA), a nitric oxide (NO)- and nitrite (NO2−)-derived electrophilic fatty acid metabolite, displays anti-inflammatory and anti-fibrotic signaling actions and therapeutic benefit in murine models of ischemia-reperfusion, atrial fibrillation, and pulmonary hypertension. Muscle LIM protein-deficient mice (Mlp−/−) develop dilated cardiomyopathy (DCM), characterized by impaired left ventricular function and increased ventricular fibrosis at the age of 8 weeks. This study investigated the effects of NO2-OA on cardiac function in Mlp−/− mice both in vivo and in vitro. Mlp−/− mice were treated with NO2-OA or vehicle for 4 weeks via subcutaneous osmotic minipumps. Wildtype (WT) littermates treated with vehicle served as controls. Mlp−/− mice exhibited enhanced TGFβ signalling, fibrosis and severely reduced left ventricular systolic function. NO2-OA treatment attenuated interstitial myocardial fibrosis and substantially improved left ventricular systolic function in Mlp−/− mice. In vitro studies of TGFβ-stimulated primary cardiac fibroblasts further revealed that the anti-fibrotic effects of NO2-OA rely on its capability to attenuate fibroblast to myofibroblast transdifferentiation by inhibiting phosphorylation of TGFβ downstream targets. In conclusion, we demonstrate a substantial therapeutic benefit of NO2-OA in a murine model of DCM, mediated by interfering with endogenously activated TGFβ signaling. 相似文献
992.
Peng Xu Xin Ji Hongmin Yang Junlei Qi Weitao Zheng Volker Abetz Shimei Jiang Jiacong Shen 《Materials Chemistry and Physics》2010,119(1-2):249-253
Highly ordered iron oxide nanoparticles with controlled size and spacing over a large surface area were prepared with polystyrene-block-poly(2-vinyl pyridine) (PS-b-P2VP) diblock copolymer template, the obtained nanoparticles could be used as catalysts for CNTs growth in a plasma-enhanced chemical vapor deposition (PECVD) system. This route offers the capability of controlling the density of CNTs on the substrate by altering the growing time, and aligned CNTs grew vertically onto the substrates with a pre-coating of aluminium oxide (Al2O3) layer. In addition, Au nanoparticles were successfully attached to the sidewall of deposited CNTs through in situ synthetic method. 相似文献
993.
Volker Bungard Jean Mahowald Danile Waldmann Stefan Maas Arno Zürbes 《Beton- und Stahlbetonbau》2010,105(8):509-520
Bei der Anwendung dynamischer Untersuchungsmethoden zur Zustandsbewertung von Ingenieurbauwerken aus Stahl‐ und Spannbeton sowie Verbundbau spielen Veränderungen von Rand‐ und Umweltbedingungen auf die modalen Parameter eine wesentliche Rolle. Während man diese im Laborexperiment weitest gehend überwachen bzw. ausschließen kann, sind sie bei in‐situ Versuchen nur schwer zu kontrollieren. Am Beispiel einer Verbundbrücke soll demonstriert werden, welche Größenordnung die Veränderung von Randbedingungen (z. B. Veränderung von anregenden Kräften) und Umwelteinflüsse (z. B. Temperatur) auf die dynamischen Parameter einer in‐situ Struktur haben können. Die Größenordnung dieser Veränderungen wird mit Veränderungen, die aus wirklichen Strukturschäden resultieren können, verglichen und bewertet. Dynamic Condition Assessment of a Composite Bridge: Investigation of External and Nonlinear Influences on the Modal Properties Using dynamic investigation methods to assess the state of civil constructions like reinforced and prestressed concrete structures as well as composite structures, changes in boundary conditions and environmental influences play a decisive role. Under laboratory conditions it is possible to control respectively to exclude these influences but it is not always possible to control and to exclude them when testing in‐situ. By means of dynamic measurements which are conducted on a composite bridge, possible changes in dynamic properties resulting from changes in the amplitude of the excitation force and resulting from changes in the temperature conditions are demonstrated. The dimension of these changes is compared with changes in modal properties resulting from real structural defects and structural damages. 相似文献
994.
Norbert Moszner Frank Zeuner Urs Karl Fischer Volker Rheinberger Armin de Meijere Viktor Bagutski 《大分子材料与工程》2006,291(1):83-89
Summary: The radical polymerization of different substituted methyl 2‐(bicyclo[3.1.0]hex‐1‐yl) acrylates, 1a – f , was initiated by 2,2′‐azoisobutyronitrile (AIBN) at 65 °C in chlorobenzene. The radical homopolymerization of 1a – f occurred through the opening of the cyclopropane ring, and lead to polymers with number‐average molecular weights of 13 000 to 434 400 g · mol?1 and glass transition temperatures between 77 and 121 °C. The monomers 1a – f showed a similar reactivity to MMA (in the copolymerization with MMA). Selected monomers were determined to be diluent monomers for dental filling composites and enable the preparation of composites that show a significantly reduced polymerization shrinkage, compared to composites based on dimethacrylate diluents.
995.
Fourier transform near-infrared (FT-NIR) Raman microspectroscopy was adopted for analyzing the micro mechanical tensile deformation behavior of cellulosic plant fibers. Mechanical strength parameters such as tensile strength, failure strain, and Young's modulus of diversified hemp fibers were determined within the range of single fiber cells and fiber filaments. The analysis of fiber deformation at the molecular level was followed by the response of a characteristic Raman signal of fiber cellulose that is sensitive to the tensile load applied. The frequency shift of the Raman signal at 1095 cm(-1) to lower wavenumbers was observed when the fibers were subjected to tensile strain. Microstructural investigations using electron microscopy under environmental conditions supported the discussion of mechanical properties of hemp fibers in relation to several fiber variabilities. Generally, mechanical strength properties of diversified hemp fibers were discussed at the molecular, microstructural, and macroscale level. It was observed that mechanical strength properties of the fibers can be controlled in a broad range by appropriate mercerization parameters such as alkali concentration, fiber shrinkage, and tensile stress applied to the fibers during the alkaline treatments. 相似文献
996.
We present the computer program SearchXLinks that analyzes mass spectra with the aim of identifying disulfide bonds and other modifications in proteins of known amino acid sequence. Disulfide bonds can be intra- or intermolecular. To decrease the number of false positives, the analysis of in-source decay and tandem mass spectra are coupled into the program. The steps taken during a SearchXLinks run are outlined, and the computational costs are discussed. The application of the program is illustrated by the analysis of data from recent studies on bovine ribonuclease A and bovine serum albumin. The software can be used free of charge on the Internet at http://www.searchxlinks.de. 相似文献
997.
Speckle pattern decorrelation reduces the accuracy of interferometric shape and deformation measurements. We introduce a technique for the reduction of speckle noise in digital holography. The method is not based on classical filtering techniques such as median filters. Instead it utilizes the shift theorem of the Fourier transform. For this method several holograms of the same object under test are recorded. The reconstruction leads to a set of object wave fields with different speckle patterns. A proper averaging procedure, taking into account the properties of the wrapped phases, leads to an improvement of the accuracy in the resulting phase difference. The theory of the applied method is described and our first results for technical components with an improvement of accuracy up to 1/57 of the wavelength are presented. 相似文献
998.
999.
Dorit Helbig Volker Bhm Andreas Wagner Rainer Schubert Gerhard Jahreis 《Food chemistry》2008,111(4):1043-1049
Berry seeds are distinguished by longevity though clear scientific appraisals cannot be made. Besides a hard seed coat other protecting substances are presumed in the seeds. Commonly the seeds are utilized as a source of oils. After pressing, there is a residue left that is still rich in bioactive ingredients. This paper gives an overview of the health-beneficial ingredients remaining in the residue of various berry seeds (bilberry, cranberry, rose hip, strawberry, elder, and black currant) with special focus on black currant. The fatty acid distribution and the content of fat, tocopherols and tocotrienols, phytosterols, carotenoids, vitamin C, fibre, protein, amino acids, dry matter, ashes, minerals, total phenols (gallic acid equivalent) and antioxidant capacity (TEAC) were determined. The investigation of berry seed press residues revealed that the total phenols and tocopherols were quantitatively the most important features of this material but there were significant differences between batches and cultures. 相似文献
1000.
Florian Hanusch Robert Kender Volker Engel Sebastian Rehfeldt Harald Klein 《American Institute of Chemical Engineers》2019,65(8):e16598
Liquid maldistribution is one of the main deficiencies in random packed column design. Therefore, the knowledge of liquid distribution and its model-based prediction is of great interest. This work aims to further develop and validate the TUM–WelChem Cell Model for random packed columns. First, cell dimension calculations and the determination of random packing element orientations are standardized. The original WelChem Cell Model applies a liquid distribution mechanism based on liquid spread factors derived by virtual 3D irrigation experiments. An extension of the model involves the implementation of liquid and gas load related distribution mechanisms, considering dispersion effects caused by liquid loading and the countercurrent gas flow. The wall flow is refined by an increase of packing porosity at the column wall. Liquid distribution profiles provided by the TUM–WelChem Cell Model are validated against experimental data and show good agreement for both uniform and point source initial liquid distribution. 相似文献