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51.
M. Jeyakanthan Uma Subramanian R. B. Tangsali 《Journal of Materials Science: Materials in Electronics》2018,29(3):1914-1924
CoWO4/PbWO4 nanocomposites were successfully synthesized at room temperature (RT) by co-precipitation route without using any templates or surfactants and sintered at 600 °C for good crystallization. The sintered samples were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy and Zeta potential measurements. UV–Visible diffuse reflectance spectroscopy, photoluminescence (PL) and PL lifetime were studied at RT. The results indicate that the composites have two-phase composition: CoWO4 and PbWO4. SEM micrograph and zeta potential measurements reveal particle agglomeration. The intrinsic PL peak emission at 467 nm of CoWO4 nano sample was enhanced upto four times by optimizing the atomic ratio of Pb/Co concentration. The interconnected interface of CoWO4/PbWO4 nanocomposites could have led to increase in number of recombination of electron hole pairs in CoWO4 and enhanced its intrinsic PL emission intensity. The mechanism of enhanced PL emission for the CoWO4/PbWO4 nanocomposites can be attributed to charge transfer between [WO4]2? and [WO6]6? complexes due to intra particle agglomeration leading to possible interface. 相似文献
52.
The future of iron pnictide superconductors in technology is still undecided. While these materials are now known to possess relatively high critical temperatures and critical magnetic fields, processing methods for these superconductors are still in the development stage. Recently we have been investigating possible ways to speed up the synthetic process for obtaining polycrystalline iron arsenide superconductors and other transition metal pnictides. Here we report the synthesis of NdFeAsO and NdFe0.9Co0.1AsO in less than 1 h total exposure to microwave radiation using an additional microwave susceptor to surround the reaction ampoule. Structure and property measurements reveal the samples to be of high quality and superconducting when Co doped. 相似文献
53.
To assess the effects of aging time (0, 15, 30, and 45 d) and temperature (0 or 5 °C) on beef mitochondria and steak color, vacuum packaged longissimus (n = 15) and cardiac muscles were assigned to 1 of 6 temperature × time combinations. As time increased, initial red color intensity increased whereas both mitochondrial oxygen consumption and color stability decreased. The decrease in mitochondrial oxygen consumption associated with longer aging times will increase initial color intensity. However, this improvement in color development will be negated by the decreased color stability that results from the effects of storage on mitochondria. 相似文献
54.
H. Subramanian P. Madasamy V. S. Sathyaseelan T. V. Krishnamohan S. Velmurugan S. V. Narasimhan 《工业材料与腐蚀》2012,63(1):29-35
Carbon steel feeders in the primary heat transport system of pressurized heavy water reactors (PHWRs) show significant wall thinning due to flow accelerated corrosion (FAC). This is of great concern, as the wear rate in certain locations exceeds the corrosion allowance by design. This necessitates periodic measurement of wall thickness and in some cases even mid course enmasse replacement of feeders. While analyzing the data on wall thicknesses and in arriving at the wall thinning rate during operation of the reactor, sufficient care has to be taken to account for the wall thinning occurring during full system chemical decontamination campaign which is carried out occasionally to reduce dose rates during reactor shut down. Chemical decontamination of primary heat transport system is carried out using a mixture of organic acids at a total concentration of about 0.1 g/L and at 85 °C. The results of experiments carried out under simulated conditions for estimating the wall thinning occurring in carbon steel feeder elbow during dilute chemical decontamination are described in this work. The corrosion rates are quantified. 相似文献
55.
Komathi Shanmugasundaram Palaniappan Subramanian Manisankar Paramasivam Gopalan Anantha Iyengar Kwang-Pill Lee 《Gold bulletin》2011,44(1):37-42
Functional nanofibrous polymer membranes were prepared by incorporating poly(2-aminothio phenol) (P2AT) stabilized Au NPs
onto electrospun polyvinylidene fluoride (PVdF) nanofibers (designated as P2AT-Au NPs@PVdF-NFM). The preparation of P2AT-Au
NPs@PVdF-NFM involves two steps: loading of 2AT (monomer) into electrospun PVdF nanofibrous membrane and polymerization of
2AT by gold chloride. P2AT and Au NPs were simultaneously formed into the electrospun PVdF-NFM. Transmission electron microscope
image of P2AT-Au NPs@PVdF-NFM informs the presence of Au NPs (with sizes ~10 nm) onto PVdF-NFM. 相似文献
56.
Aarthy K Chindhanaiselvam Anitha Priya John Abraham Nambirajan Subramanian 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(19):2823-2829
Dwarf Poinciana (Caesalpinia pulcherrima) seeds are studied for first time for the extraction of bio-oil. The dried and crushed seeds are optimized for maximum yield of bio-oil with a series of polar and nonpolar solvents and recovered by a simple distillation process. Methanol is found to yield the maximum bio-oil. The fatty acid analysis of bio-oil reveals the prevalence of linoleic acid (54.67%), followed by palmitic acid (16.9%), stearic acid (12.5%), and oleic acid (10.32%). Basic fuel properties like specific gravity, viscosity, refractive index, iodine value, saponification value, fire point, flash point, pour point, and calorific value are studied. 相似文献
57.
58.
Optimization of Lithium Content and Sintering Aid for Maximized Li+ Conductivity and Density in Ta‐Doped Li7La3Zr2O12 下载免费PDF全文
Narayanasamy Janani Sampathkumar Ramakumar Subramanian Kannan Ramaswamy Murugan 《Journal of the American Ceramic Society》2015,98(7):2039-2046
Ta‐doped cubic phase Li7La3Zr2O12 (LLZ) lithium garnet received considerable attention in recent times as prospective electrolyte for all‐solid‐state lithium battery. Although the conductivity has been improved by stabilizing the cubic phase with the Ta5+ doping for Zr4+ in LLZ, the density of the pellet was found to be relatively poor with large amount of pores. In addition to the high Li+ conductivity, density is also an essential parameter for the successful application of LLZ as solid electrolyte membrane in all‐solid‐state lithium battery. Systematic investigations carried out through this work indicated that the optimal Li concentration of 6.4 (i.e., Li6.4La3Zr1.4Ta0.6O12) is required to obtain phase pure, relatively dense and high Li+ conductive cubic phase in Li7?xLa3Zr2?xTaxO12 solid solutions. Effort has been also made in this work to enhance the density and Li+ conductivity of Li6.4La3Zr1.4Ta0.6O12 further through the Li4SiO4 addition. A maximized room‐temperature (33°C) total (bulk + grain boundary) Li+ conductivity of 3.7 × 10?4 S/cm and maximized relative density of 94% was observed for Li6.4La3Zr1.4Ta0.6O12 added with 1 wt% of Li4SiO4. 相似文献
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