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861.
The α-amylase inhibitory activity of 28 varieties of chick pea (Cicer arietinum L) was determined, and KGT/GBS-8 was found to have the greatest activity (81.4 units g?1). The inhibitor was heat labile and the inhibitory activity decreased during germination.  相似文献   
862.
Individuated finger and wrist movements can be decoded using random subpopulations of neurons that are widely distributed in the primary motor (M1) hand area. This work investigates 1) whether it is possible to decode dexterous finger movements using spatially-constrained volumes of neurons as typically recorded from a microelectrode array; and 2) whether decoding accuracy differs due to the configuration or location of the array within the M1 hand area. Single-unit activities were sequentially recorded from task-related neurons in two rhesus monkeys as they performed individuated movements of the fingers and the wrist. Simultaneous neuronal ensembles were simulated by constraining these activities to the recording field dimensions of conventional microelectrode array architectures. Artificial neural network (ANN) based filters were able to decode individuated finger movements with greater than 90% accuracy for the majority of movement types, using as few as 20 neurons from these ensemble activities. Furthermore, for the large majority of cases there were no significant differences (p < 0.01) in decoding accuracy as a function of the location of the recording volume. The results suggest that a brain-machine interface (BMI) for dexterous control of individuated fingers and the wrist can be implemented using microelectrode arrays placed broadly in the M1 hand area.  相似文献   
863.
The present study investigates the effect of earthquake sequences on the response of reinforced concrete hilly buildings having typical configurations, that is, stepback and split-foundation, with three different story ratios. A set of 30 as-recorded mainshock-aftershock sequence of earthquake ground motions is considered for this study. Mainshock acceleration time histories are scaled at two distinct intensity levels to obtain the mainshock-damaged building. These mainshock-damaged hilly buildings are then subjected to aftershocks. A comparative study is performed for various response quantities, such as peak interstory drift ratio, peak floor acceleration, and peak roof displacement of undamaged and mainshock-damaged buildings under aftershocks. Further, fragility analysis is carried out to study the effect of aftershocks on undamaged and mainshock-damaged hilly buildings. Subsequently, component-wise seismic loss estimation due to damage in the non-structural and structural components is performed. It is concluded from the study that the building components that contribute maximum to the expected repair cost ratio vary with respect to the intensity of the aftershocks. Also, the estimated seismic loss is higher in mainshock-damaged split-foundation buildings in comparison to stepback buildings.  相似文献   
864.
This paper presents the design of output feedback controllers for discrete-time (DT) linear systems. New sufficient LMI conditions are derived for designing static H 2 $$ {H}_2 $$ and H $$ {H}_{\infty } $$ controllers using decomposition of an auxiliary matrix. The decomposition facilitates linearization of nonlinear term of reduced size to obtain linear matrix inequality criteria. This leads to less conservative results as shown in the numerical examples. In addition, the proposed static output feedback criteria is also used for designing dynamic output feedback controllers for DT systems. Furthermore, a comparative study is also made for the proposed design method with the results existing in the literature. Finally, a DT static output feedback H $$ {H}_{\infty } $$ controller is designed for a quarter-car suspension system. Simulation results are provided to show the efficacy of the proposed design method.  相似文献   
865.
Ojha  Avinash  Aggarwal  Praveen 《SILICON》2022,14(6):2453-2472
Silicon - Manufacturing of ordinary Portland cement is an energy intensive process that emits harmful greenhouse gases in the atmosphere which pollutes the environment. With the surge in...  相似文献   
866.
Two-dimensional layered transition metal dichalcogenides have emerged as promising materials for supercapacitors and hydrogen evolution reaction (HER) applications. Herein, the molybdenum sulfide (MoS2)@vanadium sulfide (VS2) and tungsten sulfide (WS2)@VS2 hybrid nano-architectures prepared via a facile one-step hydrothermal approach is reported. Hierarchical hybrids lead to rich exposed active edge sites, tuned porous nanopetals-decorated morphologies, and high intrinsic activity owing to the strong interfacial interaction between the two materials. Fabricated supercapacitors using MoS2@VS2 and WS2@VS2 electrodes exhibit high specific capacitances of 513 and 615 F g1, respectively, at an applied current of 2.5 A g1 by the three-electrode configuration. The asymmetric device fabricated using WS2@VS2 electrode exhibits a high specific capacitance of 222 F g1 at an applied current of 2.5 A g1 with the specific energy of 52 Wh kg1 at a specific power of 1 kW kg1. For HER, the WS2@VS2 catalyst shows noble characteristics with an overpotential of 56 mV to yield 10 mA cm2, a Tafel slope of 39 mV dec−1, and an exchange current density of 1.73 mA cm2. In addition, density functional theory calculations are used to evaluate the durable heterostructure formation and adsorption of hydrogen atom on the various accessible sites of MoS2@VS2 and WS2@VS2 heterostructures.  相似文献   
867.
Scope: Mushrooms are valued as an edible and medical resource for millennia. As macrofungi, they possess conserved molecular components recognized by innate immune cells like macrophages, yet unlike pathogenic fungi, they do not trigger the immune system in the same way. That these well-tolerated foods both avoid immuno-surveillance and have positive health benefits, highlights the dearth of information on the interactions of mushroom-derived products with the immune system. Methods and results: Using powders produced from the common white button mushroom, Agaricus bisporus, it is observed that pre-treatment of mouse and human macrophages with mushroom powders attenuates innate immune signaling triggered by microbial ligands like LPS and  β-glucans, including NFκB activation and pro-inflammatory cytokine production. This effect of mushroom powders is observed at lower doses of TLR ligands, suggesting a model of competitive inhibition whereby mushroom compounds bind and occupy innate immune receptors, precluding activation by microbial stimuli. This effect is preserved following simulated digestion of the powders. Moreover, in vivo delivery of mushroom powders attenuates the development of colitis in a DSS-mouse model. Conclusion: This data highlights an important anti-inflammatory role for powdered A. bisporus mushrooms, which can be further utilized to develop complementary approaches to modulate chronic inflammation and disease.  相似文献   
868.
Commercial α‐amylase preparation (Biotempase) and crude glucoamylase from Aspergillus sp. NA21 were used to hydrolyse pearlmillet, a non‐conventional starchy substrate. Various concentrations of starch (15—35% w/v) were used for liquefaction; 25% slurry was found to be judicious and optimal. Liquefaction in steam under pressure 2.06—2.75 N/cm2, 104—105 °C) was found to be more economical than in a water bath at 95 °C. In the first case a 25% (w/v) slurry was liquefied in 60 min. A pH of 5.0 was found to be optimum for liquefaction. Biotempase dose was cut down by 33% to the prescribed one by addition of 150 ppm CaCl2 to the slurry. Ninety percent saccharification of liquefied pearlmillet occurred under optimum conditions (24 h and pH 5.0). The optimum temperature for saccharification of pearlmillet was found to be 45 °C. Additions of Ca2+, Mg2+ and Zn2+ were found to have no effect on saccharification. Glucose was found to be the main hydrolysis product as indicated by paper chromatography.  相似文献   
869.
Due to various structural and optical properties, metal chalcogenide nanomaterials are favorable candidates for different optoelectronic applications. In the current report, Cu2Te/NiTe nanocomposites were synthesized via the facile hydrothermal method. With the variation of concentration of Cu and Ni, various materials had been prepared along with pure Cu2Te and NiTe. The observed several vibrational modes in the material through the Raman spectroscopy are well agreed with the appearing phases. The morphological study confirmed the nanostructures are combination of nanoparticles with sheets. The size of nanoparticles varied in the range of 66–34 nm. The absorbance spectra of the nanocomposite exhibit a blueshift and support the enhancement in the optical bandgap. The value of bandgap energy of the composite samples has been noted in the range of 1.8–2.2 eV. This bandgap range enables the material for various optoelectronic applications such as solar cell and other photovoltaic devices. Thermal analysis of the material demonstrates the presences of several endothermic and exothermic peaks. Thus, several studies on the material prevail its various applicability as optoelectronics as well as other thermal application.  相似文献   
870.
Journal of Inorganic and Organometallic Polymers and Materials - This report compares the properties of mono-substituted hierarchically assembled nanostructured apatitic (HANA) particles. The Mg2+...  相似文献   
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