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An oil based nanofluid including silver as to be nanoparticles was created by EEW method as a one‐step method in three different volume fractions have been experimentally studied. Assessing the stability and viscosity of the nanofluids was involved in this work. The results show that the nanofluids behave in both of Newtonian and non‐Newtonian in different volume concentrations. Also, an enhancement in viscosity of nanofluids has been recognized. In addition, based on the experimental results of this study and the other previous published studies on the oil based nanofluids, a correlation for predicting viscosity of oil based nanofluids has been developed and a good agreement between the experimental viscosity of applied nanofluids in this study and the predicted one has been achieved.  相似文献   
43.
Bulletin of Engineering Geology and the Environment - In this research, landslide susceptibility map of the Fahliyan sub-basin was provided employing adaptive neuro-fuzzy inference system (ANFIS)...  相似文献   
44.
Iranian Polymer Journal - Toward sustainability of polymer-matrix composites, this study aimed to prepare and evaluate glass fiber reinforced (GFR) biocomposites of fully bio-based furan resin, and...  相似文献   
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Chaotic advection plays an important role in microplatforms for a variety of applications. Currently used mechanisms for inducing chaotic advection in small scale, however, are limited by their complicated fabrication processes and relatively high power consumption. Here, a soft actuator is reported which utilizes a droplet of Galinstan liquid metal to induce harmonic Marangoni flow at the surface of liquid metal when activated by a sinusoidal signal. This liquid metal actuator has no rigid parts and employs continuous electrowetting effect to induce chaotic advection with exceptionally low power consumption. The theory behind the operation of this actuator is developed and validated via a series of experiments. The presented actuator can be readily integrated into other microfluidic components for a wide range of applications.  相似文献   
47.
Liquid metals offer unprecedented chemistry. Here it is shown that they can facilitate self‐limiting oxidation processes on their surfaces, which enables the growth of metal oxides that are atomically thin. This claim is exemplified by creating atomically thin hydrated MnO2 using a Galvanic replacement reaction between permanganate ions and a liquid gallium–indium alloy (EGaIn). The “liquid solution”–“liquid metal” process leads to the reduction of the permanganate ions, resulting in the formation of the oxide monolayer at the interface. It is presented that under mechanical agitation liquid metal droplets are established, and simultaneously, hydrated gallium oxides and manganese oxide sheets delaminate themselves from the interfacial boundaries. The produced nanosheets encapsulate a metallic core, which is found to consist of solid indium only, with the full migration of gallium out of the droplets. This process produces core/shell structures, where the shells are made of stacked atomically thin nanosheets. The obtained core/shell structures are found to be an efficient photocatalyst for the degradation of an organic dye under simulated solar irradiation. This study presents a new research direction toward the modification and functionalization of liquid metals through spontaneous interfacial redox reactions, which has implications for many applications beyond photocatalysis.  相似文献   
48.
Modified polyester fibers are considered as a significant part of the polyester produced throughout the world due to the new properties and also reduced undesirable properties, compared to non-modified polyester fibers. In this study, the modification of polyester fiber properties was evaluated for its superabsorbency. The fibers obtained superabsorbency by their treatment with a special latex prepared by inverse emulsion polymerization. Different polymer latexes based on acrylic acid, sodium acrylate, acrylamide (AM) and 2-acrylamide-2-methyl propane sulfonic acid were prepared using inverse emulsion polymerization. Chemical bond (or hydrogen bond) was formed between the functional groups of the fiber surface and functional groups present in the polymer latex by heating. The modified fibers were characterized by swelling, mechanical, morphological, and thermal measurements. The effect of several modifications of parameters such as latex type, AM content in latex, aquatic-organic phase ratios of latex, modification time and modification temperature on the swelling properties of fibers were investigated. Water absorption of the unmodified fiber was 1.5 g/g which increased up to 75 g/g, significantly. This considerable development in hydrophilic characteristics of polyester fibers has led to water blocking of the fiber. Such modification did not have adverse effects on the tensile properties or thermal resistance of the polyester fiber.  相似文献   
49.
The performance of two tetrafluoroborate-based ionic liquids (ILs) as entrainers in the dehydration of water/ethanol azeotropic mixtures was evaluated. Isobaric vapor-liquid equilibrium (VLE) data were measured for the systems ethanol/water/1-butyl-3-methyl imidazolium tetrafluoroborate and ethanol/water /n-butylpyridinium tetrafluoroborate including the azeotropic region. VLE data for the ethanol/water, ethanol/IL, and water/IL binary mixtures were obtained at 100 kPa. The hydrolysis of the tetrafluoroborate anion was studied for both types of ILs by 19F NMR analysis. The hydrolysis of the tetrafluoroborate anion does not have much effect on the ethanol/water VLE. The 19F NMR analysis indicated that hydrolysis occurred at high mole fractions of water.  相似文献   
50.
3′-Deoxynucleotides are an important class of drugs because they interfere with the metabolism of nucleotides, and their incorporation into DNA or RNA terminates cell division and viral replication. These compounds are generally produced by multi-step chemical synthesis, and an enzyme with the ability to catalyse the removal of the 3′-deoxy group from different nucleotides has yet to be described. Here, using a combination of HPLC, HRMS and NMR spectroscopy, we demonstrate that a thermostable fungal radical S-adenosylmethionine (SAM) enzyme, with similarity to the vertebrate antiviral enzyme viperin (RSAD2), can catalyse the transformation of CTP, UTP and 5-bromo-UTP to their 3′-deoxy-3′,4′-didehydro (ddh) analogues. We show that, unlike the fungal enzyme, human viperin only catalyses the transformation of CTP to ddhCTP. Using electron paramagnetic resonance spectroscopy and molecular docking and dynamics simulations in combination with mutagenesis studies, we provide insight into the origin of the unprecedented substrate promiscuity of the enzyme and the mechanism of dehydration of a nucleotide. Our findings highlight the evolution of substrate specificity in a member of the radical-SAM enzymes. We predict that our work will help in using a new class of the radical-SAM enzymes for the biocatalytic synthesis of 3′-deoxy nucleotide/nucleoside analogues.  相似文献   
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