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131.
Ali Gökhan Demir Barbara Previtali 《The International Journal of Advanced Manufacturing Technology》2014,75(9-12):1557-1568
Thin sheet anode and cathode materials made in composite structures constitute some of the most important components of a Li-ion battery. These materials are currently cut by punching technology, which shows degrading behaviour as the tool wears out. A viable option for Li-ion battery electrode manufacturing is the use of remote laser cutting. However, the operation requires fulfilling both productivity and quality aspects to substitute the conventional production method. One of the most critical aspects in quality is the clearance width, which is defined as the extent of the exposed middle layer of the sandwich at the laser cut kerf. This work investigates the quality aspects of laser cutting of Li-ion electrodes when a green fibre laser source (λ?=?532 nm, τ?=?1 ns) is used rather than the more traditional infrared (IR) fibre laser source (λ?=?1,064 nm, τ?=?250 ns). The processing conditions were investigated to reveal the technological feasibility zones. Clearance width was studied within the technological feasibility zones for all the material-laser combinations. Results showed that high productivity criterion is met by the IR system, since cutting speed could reach 30 m/min with 54 W average laser power on both anode and cathode. On the other hand, the green laser provided clearance width below 20 μm. In the best case, the clearance on anode could be eliminated with the green laser system. Although the maximum cutting speed was 4.5 m/min, upscaling of green laser power can provide required productivity. 相似文献
132.
133.
Barbara 《中国室内装饰装修天地》2010,(6):96-97
儿童总是喜爱玩耍的,神秘的洞穴更是对他们有着无穷的吸引力。在孩子的眼中,色彩是丰富世界的一个缩影。因此,迫庆一郎先生在设计巴塞罗那儿童品牌Imaginarium旗舰店时,就以洞穴·彩虹作为了设计的主题。 相似文献
134.
135.
Carbon foams are non-toxic, highly porous, light materials which demonstrate a wide range of properties. That fact allows carbon foams to be applied in many areas of life, ranging from electronics industry, through machinery, car and construction industry, to environmental protection. The properties of carbon foams are closely connected with their density, and its value is especially influenced by their internal structure, i.e. mainly size and number of pores, pore wall thickness and structural order of solid matrix. That is why it is possible to design the properties of carbon foams by controlling their growth. The main control factors are selecting the suitable raw material, the process parameters (temperature and pressure) and the suitable production method. Additionally, the properties of carbon foams may be modified by doping them with carbon or mineral fillers. The second method is the enrichment of carbon matrix with heteroatoms, mainly of boron and nitrogen. This paper presents the review of the possibilities of tailoring the structure and properties of carbon foams, based on the current level of knowledge available in the literature. 相似文献
136.
Prof. Dr. Reiner Doluschitz Dr. sc. Agr Barbara Engler Christa Hoffmann Dipl.-Ing. Agr. 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2010,68(1):11-19
Based on the information needs of stakeholders (from animal feed to consumers, including the authorities and organizations
involved) an integrated IT-system without structural fractures and barriers shall be developed. It will be designed to enable
the merging, internal exchange and utilization of relevant data and parameters. Subprojects of the interdisciplinary research
consortium cover the entire supply chain and also address cross-section issues, such as logistics, costs and benefits, veterinarian
services, quality assurance systems, a comprehensive IT-solution including data format standards (agroXML), and requirements
for sustainability. Substantial added value has been generated from intensive interdisciplinary co-operation. The interdisciplinary
research project IT FoodTrace () aims at achieving traceability and quality assurance along the food chain of “meat and meat products”. The aim of this paper
is the presentation of (a) the complexity of underlying problems, (b) the project structure, (c) available results from selected
sub-projects and (d) the added values from interdisciplinary co-operation. Selected findings include an optimized single animal
data collection and information management in livestock systems, benefits gained by linking animal-health-related information
to an integrated animal-health system, requirements and features of an integrated IT-System, including consequences for data
protection and security, and findings from a Delphi-based cost–benefit-analysis of an integrated quality assurance and traceability
system. 相似文献
137.
138.
Anna Fischer Manuel Schmitz Barbara Aichmayer Peter Fratzl Damien Faivre 《Journal of the Royal Society Interface》2011,8(60):1011-1018
Magnetosome biomineralization and chain formation in magnetotactic bacteria are two processes that are highly controlled at the cellular level in order to form cellular magnetic dipoles. However, even if the magnetosome chains are well characterized, controversial results about the microstructure of magnetosomes were obtained and its possible influence in the formation of the magnetic dipole is to be specified. For the first time, the microstructure of intracellular magnetosomes was investigated using high-resolution synchrotron X-ray diffraction. Significant differences in the lattice parameter were found between intracellular magnetosomes from cultured magnetotactic bacteria and isolated ones. Through comparison with abiotic control materials of similar size, we show that this difference can be associated with different oxidation states and that the biogenic nanomagnetite is stoichiometric, i.e. structurally pure whereas isolated magnetosomes are slightly oxidized. The hierarchical structuring of the magnetosome chain thus starts with the formation of structurally pure magnetite nanoparticles that in turn might influence the magnetic property of the magnetosome chains. 相似文献
139.
Marika Vespa Erich Wieland Rainer Dähn Barbara Lothenbach 《Journal of the American Ceramic Society》2015,98(7):2286-2294
Current developments in cement chemistry increasingly rely on predictive thermodynamic modeling of the phase composition in cementitious composites with the aim of linking the performance of the material with the phase composition of the material. This approach requires identification of the cement phases that form in hydrating cementitious materials using standard techniques, such as X‐ray diffraction (XRD) and thermal analysis (DTA, TGA), but also state‐of‐the‐art synchrotron‐based techniques, in particular for those cases in which the signals of solid solutions overlap in XRD and TGA measurements. In this study, two ordinary Portland cements, with different chemical compositions and subject to different hydration times (~10, ~50 yr), were investigated aiming at identifying the most stable Fe‐containing cement phase in the cement pastes. The Fe‐containing cement phases and their solid solutions with the Al analogues in the complex cement matrix were analyzed with X‐ray absorption spectroscopy, indicating the formation of a mixed Fe–Al siliceous hydrogarnet as the major Fe‐containing phase. The presence of this phase after long hydration periods and upon selective dissolution of the pastes further indicates that, independent of the chemical compositions of cements, formation of the mixed Fe–Al siliceous hydrogarnet is thermodynamically favored in aged pastes, which is supported by published thermodynamic calculations. 相似文献
140.
Platelet lysate and adipose mesenchymal stromal cells on silk fibroin nonwoven mats for wound healing 下载免费PDF全文
Chlapanidas Theodora Perteghella Sara Faragò Silvio Boschi Alessandra Tripodo Giuseppe Vigani Barbara Crivelli Barbara Renzi Sabrina Dotti Silvia Preda Stefania Marazzi Mario Torre Maria Luisa Ferrari Maura 《应用聚合物科学杂志》2016,133(5)
In this work platelet lysate (PL) and adipose‐derived mesenchymal stromal cells (ASCs) seeded on nonwoven fibroin mats were in vitro and in vivo evaluated for tissue regenerative applications. Nonwoven mats obtained by a large scale water entanglement technique were characterized for their physico‐chemical properties. Results indicated a high purity of fibroin fibers, their stability after sterilization process and appropriate technological properties suitable for tissue engineering. Moreover, the scaffolds in vitro supported adhesion and migration of ASCs and the presence of PL improved the cell proliferation. The products were then applied on epithelial/dermal wounds carried out on the dorsal surface of rabbit: the skin reparative process was solved in 9 days, with a completely restitutio ad integrum of the epithelium in animals treated with PL alone; ASCs did not further improve the wound healing. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42942. 相似文献