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81.
Genetic algorithms use a tournament selection or a roulette selection to choice better population. But these selections couldn’t use heuristic information for specific problem. Fuzzy selection system by heuristic rule base help to find optimal solution efficiently. And adaptive crossover and mutation probabilistic rate is faster than using fixed value. In this paper, we want fuzzy selection system for genetic algorithms and adaptive crossover and mutation rate fuzzy system. This work was presented in part and awarded as Young Author Award at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   
82.
GPR55 recognizes several lipid molecules such as lysophosphatidylinositol. GPR55 expression was reported in human monocytes. However, its role in monocyte adhesion and atherosclerosis development has not been studied. The role of GPR55 in monocyte adhesion and atherosclerosis development was investigated in human THP-1 monocytes and ApoE−/− mice using O-1602 (a potent agonist of GPR55) and CID16020046 (a specific GPR55 antagonist). O-1602 treatment significantly increased monocyte adhesion to human umbilical vein endothelial cells, and the O-1602-induced adhesion was inhibited by treatment with CID16020046. O-1602 induced the expression of Mac-1 adhesion molecules, whereas CID16020046 inhibited this induction. Analysis of the promoter region of Mac-1 elucidated the binding sites of AP-1 and NF-κB between nucleotides −750 and −503 as GPR55 responsive elements. O-1602 induction of Mac-1 was found to be dependent on the signaling components of GPR55, that is, Gq protein, Ca2+, CaMKK, and PI3K. In Apo−/ mice, administration of CID16020046 ameliorated high-fat diet-induced atherosclerosis development. These results suggest that high-fat diet-induced GPR55 activation leads to the adhesion of monocytes to endothelial cells via induction of Mac-1, and CID16020046 blockage of GPR55 could suppress monocyte adhesion to vascular endothelial cells through suppression of Mac-1 expression, leading to protection against the development of atherosclerosis.  相似文献   
83.
A glucose sensor electrode was prepared with multi-walled carbon nanotubes (MWNTs) because of its effect on surface modification through oxyfluorination. The oxyfluorination of MWNTs was carried out with F2:O2 ratios of 7:3, 5:5 and 3:7, which are labeled F7O3-MWNT, F5O5-MWNT, and F3O7-MWNT, based on the oxyfluorination conditions. The hydrophilic functional groups were introduced effectively on the hydrophobic carbon surface. In addition, the amorphous area of the MWNTs was affected by oxyfluorination. The reactivity of the glucose sensor was affected by the oxyfluorination treatment and the existence of amorphous on MWNTs. The optimum O/F percentage was approximately 50%. Therefore, the oxyfluorination conditions are important with amorphous MWNTs. The sensitivity was improved based on the effects of improved interface affinity between the enzyme and the carbon electrode. In addition, the presence of an amorphous area on MWNTs seems to be beneficial for efficient glucose oxidase immobilization, which results in high-performance glucose sensing.  相似文献   
84.
Experience‐dependent synapse remodeling is associated with information storage in the nervous system. Neuronal synapses show alteration in various neurological and cognitive disorders in their structure and function. At the ultrastructural level, parallel fiber boutons contacting multiple spines of Purkinje cells in the cerebellar cortex are commonly observed in physiologically enriched animals as well as pathological ataxic mutants. However, the dendritic origin of those spines on parallel fiber multiple‐synapse boutons (MSBs) has been poorly understood. Here, we investigated this issue by 3‐dimensional ultrastructural analysis to determine synaptic connectivity of MSBs in both mice housed in physically enriched environment and cerebellar ataxic mutants. Our results demonstrated that environmental enrichment selectively induced MSBs to contact spines from the same parent dendrite, indicating focal strengthening of synapse through the simultaneous activation of two adjacent spines. In contrast, ataxic mutants displaying impaired motor coordination had significantly more MSBs involving spines originating from different neighboring dendrites compared to both wild‐type and environmentally enriched animals, suggesting that compromising multiple synapse formation may lead to abnormal motor behavior in the mutant mice. These findings propose that environmental stimulation in normal animals mainly involves the refinement of preexisting synaptic networks, whereas pathological ataxic conditions may results from less‐selective but compromising multiple synaptic formation. This study underscores that different types of multiple synapse boutons may have disparate effects on cerebellar synaptic transmission.  相似文献   
85.
2D van der Waals atomic crystal materials have great potential for use in future nanoscale electronic and optoelectronic applications owing to their unique properties such as a tunable energy band gap according to their thickness or number of layers. Recently, black phosphorous (BP) has attracted significant interest because it is a single‐component material like graphene and has high mobility, a direct band gap, and exhibits ambipolar transition behavior. This study reports on a charge injection memory field‐effect transistor on a glass substrate, where few‐layer BPs act as the active channel and charge trapping layers, and Al2O3 films grown by atomic layer deposition act as the tunneling and blocking layers. Because of the ambipolar properties of BP nanosheets, both electrons and holes are involved in the charge trapping process, resulting in bilateral threshold voltage shifts with a large memory window of 22 V. Finally, a memory circuit of a resistive‐load inverter is implemented that converts analog signals (current) to digital signals (voltage). Such a memory inverter also shows a clear memory window and distinct memory on/off switching characteristics.  相似文献   
86.
This study used an ozone/ultraviolet/hydrogen peroxide (O3/UV/H2O2) system to remove carbamazepine (CBZ) from water using a second-order response surface methodology (RSM) experiment with a five-level full-factorial central composite design (CCD) for optimization. The effects of both the primary and secondary interactions of the photocatalytic reaction variables, including O3 concentration (X1), H2O2 concentration (X2), and UV intensity (X3), were examined. The O3 concentration significantly influenced CBZ and total organic carbon (TOC) removal as well as total inorganic nitrogen ion production (T-N) (p < 0.001). However, CBZ, TOC removal, and T-N production were enhanced with increasing O3 and H2O2 concentrations up to certain levels, and further increases in O3 and H2O2 resulted in adverse effects due to hydroxyl radical scavenging by higher oxidant and catalyst concentrations. UV intensity had the most significant effect on T-N production (p < 0.001). Complete removal of CBZ was achieved after 5 min. However, only 34.04% of the TOC and 36.99% of T-N were removed under optimal concentrations, indicating formation of intermediate products during CBZ degradation. The optimal ratio of O3 (mg L? 1): H2O2 (mg L? 1): UV (mW cm? 2) were 0.91:5.52:2.98 for CBZ removal, 0.7:18.93:12.67 for TOC removal, and 0.94: 4.85:9.03 for T-N production, respectively.  相似文献   
87.
We fabricate thin epitaxial crystal silicon solar cells on display glass and fused silica substrates overcoated with a silicon seed layer. To confirm the quality of hot‐wire chemical vapor deposition epitaxy, we grow a 2‐µm‐thick absorber on a (100) monocrystalline Si layer transfer seed on display glass and achieve 6.5% efficiency with an open circuit voltage (VOC) of 586 mV without light‐trapping features. This device enables the evaluation of seed layers on display glass. Using polycrystalline seeds formed from amorphous silicon by laser‐induced mixed phase solidification (MPS) and electron beam crystallization, we demonstrate 2.9%, 476 mV (MPS) and 4.1%, 551 mV (electron beam crystallization) solar cells. Grain boundaries likely limit the solar cell grown on the MPS seed layer, and we establish an upper bound for the grain boundary recombination velocity (SGB) of 1.6x104 cm/s. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
88.
To obtain long branched polybutylene succinate (PBS), modified PBSs were prepared by introducing a branching agent, trimethylol propane (TMP), to the polycondensation system of succinic acid and 1,4‐butanediol. Molecular parameters such as absolute molecular weight and root‐mean‐square (RMS) radius of the modified PBSs were measured by gel permeation chromatography (GPC) with a multiangle laser light‐scattering (MALLS) detector. The RMS radius of TMP05, PBS prepared by incorporating 0.5 wt % TMP during polycondensation, was the smallest of all PBSs tested at the same molecular weight. The notable shear thinning and much reduced loss tangent for TMP05 qualitatively supported the difference in their molecular structures predicted by GPC. The analytical results indicated that introducing 0.5 wt % TMP produced PBS with chain branches long enough to produce molecular entanglements. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1388–1394, 2001  相似文献   
89.
The precise delivery of biofunctionalized matters is of great interest from the fundamental and applied viewpoints. In spite of significant progress achieved during the last decade, a parallel and automated isolation and manipulation of rare analyte, and their simultaneous on‐chip separation and trapping, still remain challenging. Here, a universal micromagnet junction for self‐navigating gates of microrobotic particles to deliver the biomolecules to specific sites using a remote magnetic field is described. In the proposed concept, the nonmagnetic gap between the lithographically defined donor and acceptor micromagnets creates a crucial energy barrier to restrict particle gating. It is shown that by carefully designing the geometry of the junctions, it becomes possible to deliver multiple protein‐functionalized carriers in high resolution, as well as MCF‐7 and THP‐1 cells from the mixture, with high fidelity and trap them in individual apartments. Integration of such junctions with magnetophoretic circuitry elements could lead to novel platforms without retrieving for the synchronous digital manipulation of particles/biomolecules in microfluidic multiplex arrays for next‐generation biochips.  相似文献   
90.
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