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161.
162.
Sashka Dimitrievska Juan Wang Tylee Lin Amanda Weyers Hualong Bai Lingfeng Qin Guangxin Li Chao Cai Alan Kypson Nina Kristofik Ashley Gard Sumati Sundaram Kota Yamamoto Wei Wu Liping Zhao Mehmet H. Kural Yifan Yuan Joseph Madri Themis R. Kyriakides Robert J. Linhardt Laura E. Niklason 《Advanced functional materials》2020,30(23)
Novel biological vascular conduits, such as decellularized tissue engineered vascular grafts (TEVGs) are hindered by high thrombogenicity. To mimic the antithrombogenic surface of native vessels with a continuous glycosaminoglycan layer that is present on endothelial cells (ECs), a hyaluronic acid (HA) modified surface is established, to effectively shield blood platelets from collagen‐triggered activation. Using the amine groups present on 4 mm diameter decellularized TEVGs, a continuous HA hydrogel coating is built via a bifunctional thiol‐reactive cross‐linker, thereby avoiding nonspecific collagen matrix cross‐linking. The HA hydrogel layer recreates a luminal wall, “hiding” exposed collagen from the bloodstream. In vitro blood tests show that adhered platelets, fibrinogen absorption, and fibrin formation on HA‐coated decellularized TEVGs are significantly lower than on uncoated decellularized TEVGs. The HA surface also inhibits macrophage adhesion in vitro. HA‐coated decellularized syngeneic rat aortae (≈1.5 mm diameter), and TEVGs in rat and canine models, respectively, are protected from aggressive thrombus formation, and preserve normal blood flow. Re‐endothelialization is also observed. HA‐coated TEVGs may be an off‐the‐shelf small‐diameter vascular graft with dual benefits: antithrombogenic protection and promotion of endothelium. 相似文献
163.
Vincenzo Farano Mark Cresswell Kerstin Gritsch Phil Jackson Nina Attik Brigitte Grosgogeat Jean-Christophe Maurin 《Journal of materials science. Materials in medicine》2018,29(7):101
Phosphate-based glasses have been attracting attention due to their possible medical applications arising from unique dissolution characteristics in the human body leading to the possibility of new tissue regeneration. In this study, the leaching kinetics of a series of melt-quenched Sr-doped phosphate glasses are presented. Regardless of the presence of Sr, all the glasses have an initial linear and sustained release of the ions followed by a plateau. To guarantee proper nutritional support to the growing tissue during regeneration and to mimic the 3-dimensional architecture of tissues, organic scaffold systems have been developed. However, their poor mechanical strength has limited their application. To overcome this problem, cross-linkers can be used although this then limits the solubility of the materials. To succeed in dealing with such a limitation, in this paper, by freeze-drying, the aforementioned soluble melt-quenched phosphate glasses were combined as powders with collagen fibres from bovine achilles tendon to make degradable scaffolds. The scaffolds were characterized by SEM, EDX and BET. Changes to the dissolution behaviour of the glasses arising from the presence of collagen interacting with the ions leached were reported. Furthermore, the ability of the scaffolds to induce hydroxyapatite (HA) formation was evaluated: one the elaborated scaffold could grow an HA-like layer after a week in SBF. Based on the results obtained, a possible application in restorative dentistry is proposed for one or more materials. 相似文献
164.
Elena G. Astafurova Valentina A. Moskvina Galina G. Maier Eugene V. Melnikov Gennady N. Zakharov Sergey V. Astafurov Nina K. Galchenko 《Journal of Materials Science》2017,52(8):4224-4233
Austenitic stainless steels are frequently used for hydrogen applications due to their high ductility at low temperatures and lower hydrogen environment embrittlement compared to ferritic steels. We study the effect of electrochemical hydrogen saturation up to 40 h on tensile behavior and fracture mechanisms in high-nitrogen austenitic 17Cr–24Mn–1.3V–0.2C–1.3N steel. Hydrogen saturation weakly influences the characteristic of stress–strain curves, but decreases steel ductility, yield stress, and ultimate tensile stress. Hydrogenation provides a change in steel fracture peculiarities—a hydrogen-assisted thin brittle surface layer of ≈5 μm and ductile subsurface layer of 50–150 μm in width in hydrogen-saturated specimens. The subsurface layer shows ductile transgranular fracture with elongated dimples and flat facets. The central parts of fracture surfaces for hydrogenated specimens show ductile fracture mode similar to hydrogen-free state, but they include numerous secondary cracks both for central part and for transition zone between ductile central part and subsurface layer associated with highest hydrogen saturation. The possible reasons of decrease in hydrogen-associated ductility and change in fracture character are discussed. 相似文献
165.
Lizhen Long Yaya Ding Nina Liang Jun Liu Fuchi Liu Sheng Huang Yuezhong Meng 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(27):2300519
Li–CO2 battery provides a new strategy to simultaneously solve the problems of energy storage and greenhouse effect. However, the severe polarization of CO2 reduction and CO2 evolution reaction impede the practical application. Herein, anodic TiO2 nanotube arrays are first introduced as carbon-free and free-standing cathode for photo-assisted Li–CO2 battery, and the photo-assisted charge and discharge mechanism is first clarified from the perspective of photocatalysis. Mixed-phase TiO2 exhibits a long cycling life of 580 h (52 cycles) at 0.025 mA cm−2 and delivers a high discharge specific capacity of 3001 µAh cm−2 under UV illumination. The charge voltage dramatically reduces from 4.53 to 3.03 V under UV illumination. The improvement of photo-assisted Li–CO2 battery performance relies on the synergistic effect of the hierarchical porous structure, strong UV absorption, efficient separation, and transfer of photo-generated electrons and holes at hetero-phase junction, and the facilitation of photo-generated electrons and holes on CO2 reduction and CO2 evolution reaction. This work can provide useful guidance for designing efficient photocathode for photo-assisted Li–CO2 battery and other metal–air batteries. 相似文献
166.
Joseph Nina Varghese Jobin Sebastian Mailadil Thomas 《Journal of Electronic Materials》2020,49(3):1638-1645
Journal of Electronic Materials - Thin polyvinylidene fluoride-silicon carbide (PVDF-SiC) shielding composite films were prepared by a simple solution casting process. X-ray diffraction (XRD) and... 相似文献
167.
The article focuses on how rural households cope with blackouts caused by winter storms. We approach household preparedness using a practice theory perspective, and argue that preparedness is mundanely preformed as part of everyday practices. The data material consists of at home visits to 14 households from Norway and Sweden. The results demonstrate that households cope with blackouts by activating and mobilising competences, meanings and materials belonging to different practices, and that this is an ongoing process to ensure the continuation of everyday life during disruption. The article concludes by arguing for the need to bring forward studies on informal preparedness activities, in a research field where household preparedness tends to be framed using a top‐down perspective on crisis management. 相似文献
168.
Maike Timm‐Heinrich Xuebing Xu Nina Skall Nielsen Charlotte Jacobsen 《European Journal of Lipid Science and Technology》2003,105(8):459-470
Milk drinks containing 5% traditional sunflower oil (SO), randomized lipid (RL) or specific structured lipid (SL) (both produced from SO and tricaprylin/caprylic acid) were compared with respect to their particle size, viscosity and oxidative stability during storage. Furthermore, the effect of adding potential antioxidants EDTA or gallic acid to the milk drink based on SL was investigated. The lipid type significantly affected the oxidative stability of the milk drinks: Milk drink based on SL oxidized faster than milk drink based on RL or SO. The reduced oxidative stability in the SL milk drink could not be ascribed to a single factor, but was most likely influenced by the structure of the lipid and differences in the process applied to produce and purify the lipids. EDTA was a strong antioxidant, while gallic acid did not exert a distinct antioxidative effect in the milk drink based on SL. 相似文献
169.
Zhiyuan Dong Guofeng Zhang Nina H. Amini 《International Journal of Adaptive Control and Signal Processing》2018,32(3):528-546
The single‐photon quantum filtering problems have been investigated recently with applications in quantum computing. In practice, the detector responds with a quantum efficiency of less than unity since there exists some mode mismatch between the detector and the system and the single‐photon signal may be corrupted by quantum white noise. Consequently, quantum filters based on multiple measurements are designed in this paper to improve estimation performance. More specifically, the filtering equations for a 2‐level quantum system driven by a single‐photon input state and under multiple measurements are presented in this paper. Four scenarios, ie, (1) 2 diffusive measurements with Q‐P quadrature form, (2) 2 diffusive measurements with Q‐Q quadrature form, (3) diffusive plus Poissonian measurements, and (4) 2 Poissonian measurements, are considered. It is natural to compare the filtering results, ie, measuring a single channel or both channels, which one is better? By the simulation where we use a single photon to excite an atom, it seems that multiple measurements enable us to excite the atom with higher probability than only measuring a single channel. In addition, a measurement back‐action phenomenon is revealed by the simulation results. 相似文献
170.
Biological Evaluation and X‐ray Co‐crystal Structures of Cyclohexylpyrrolidine Ligands for Trypanothione Reductase,an Enzyme from the Redox Metabolism of Trypanosoma 下载免费PDF全文
Raoul De Gasparo Dr. Elke Brodbeck‐Persch Dr. Steve Bryson Nina B. Hentzen Dr. Marcel Kaiser Prof. Dr. Emil F. Pai Prof. Dr. R. Luise Krauth‐Siegel Prof. Dr. François Diederich 《ChemMedChem》2018,13(9):957-967
The tropical diseases human African trypanosomiasis, Chagas disease, and the various forms of leishmaniasis are caused by parasites of the family of trypanosomatids. These protozoa possess a unique redox metabolism based on trypanothione and trypanothione reductase (TR), making TR a promising drug target. We report the optimization of properties and potency of cyclohexylpyrrolidine inhibitors of TR by structure‐based design. The best inhibitors were freely soluble and showed competitive inhibition constants (Ki) against Trypanosoma (T.) brucei TR and T. cruzi TR and in vitro activities (half‐maximal inhibitory concentration, IC50) against these parasites in the low micromolar range, with high selectivity against human glutathione reductase. X‐ray co‐crystal structures confirmed the binding of the ligands to the hydrophobic wall of the “mepacrine binding site” with the new, solubility‐providing vectors oriented toward the surface of the large active site. 相似文献