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501.
Malate dehydrogenase, which facilitates the reversible conversion of malate to oxaloacetate, is essential for energy balance, plant growth, and cold and salt tolerance. However, the genome-wide study of the MDH family has not yet been carried out in tomato (Solanum lycopersicum L.). In this study, 12 MDH genes were identified from the S. lycopersicum genome and renamed according to their chromosomal location. The tomato MDH genes were split into five groups based on phylogenetic analysis and the genes that clustered together showed similar lengths, and structures, and conserved motifs in the encoded proteins. From the 12 tomato MDH genes on the chromosomes, three pairs of segmental duplication events involving four genes were found. Each pair of genes had a Ka/Ks ratio < 1, indicating that the MDH gene family of tomato was purified during evolution. Gene expression analysis exhibited that tomato MDHs were differentially expressed in different tissues, at various stages of fruit development, and differentially regulated in response to abiotic stresses. Molecular docking of four highly expressed MDHs revealed their substrate and co-factor specificity in the reversible conversion process of malate to oxaloacetate. Further, co-localization of tomato MDH genes with quantitative trait loci (QTL) of salt stress-related phenotypes revealed their broader functions in salt stress tolerance. This study lays the foundation for functional analysis of MDH genes and genetic improvement in tomato.  相似文献   
502.
Journal of Superconductivity and Novel Magnetism - SmCo5 magnets were prepared by spark plasma sintering (SPS) technique. The phase constitutions, magnetic properties, and microstructures of...  相似文献   
503.
The present work is designed to discover new perovskite-based materials, which are expected to show high mechanical stability during their applications, using machine learning (ML) techniques, and based on the Pugh's criterion for distinguishing brittle and ductile behaviors. For this purpose, ML models to predict the moduli of materials, bulk (B) and shear (G), are built using their crystal structure and composition information. The ML process is initiated with the information of 5663 compounds, including composition, crystal structure and moduli, as listed in AFLOW database. Following a procedure of data characteristics, feature generation, feature processing, training, and testing, the ML models are constructed with acceptable accuracy (tenfold cross-validation R2 score of 0.90 and 0.89 for B and G, respectively). The validation process of the models, which is conducted using the corresponding density functional theory calculations, reveals that these models are reliable to be employed in a large-scale screening process. Indeed, the B- and G-based ML models are incorporated in a screening process, and this is also conjugated with other screening criterions, to find out thermodynamically stable and formable perovskite-based materials with improved mechanical performance.  相似文献   
504.
In block ciphers, the nonlinear components, also known as substitution boxes (S-boxes), are used with the purpose of inducing confusion in cryptosystems. For the last decade, most of the work on designing S-boxes over the points of elliptic curves has been published. The main purpose of these studies is to hide data and improve the security levels of crypto algorithms. In this work, we design pair of nonlinear components of a block cipher over the residue class of Gaussian integers (GI). The fascinating features of this structure provide S-boxes pair at a time by fixing three parameters. But the prime field dependent on the Elliptic curve (EC) provides one S-box at a time by fixing three parameters and . The newly designed pair of S-boxes are assessed by various tests like nonlinearity, bit independence criterion, strict avalanche criterion, linear approximation probability, and differential approximation probability.  相似文献   
505.
Efficient charge–carrier separation and their utilization are the key factors in overcoming sluggish four-electron reaction kinetics involved in photocatalytic oxygen evolution. Here, a novel study demonstrates the significance of Na2S2O8 as a sacrificial agent in comparison to AgNO3. Resultantly, BiFeO3 (BFO) and titanium doped-oxygen deficient BiFeO3 (Ti-BFO-R) nanostructures achieve ≈64 and 44.5 times higher O2 evolution in the presence of Na2S2O8 compared to AgNO3 as a sacrificial agent, respectively. Furthermore, the presence of Co single atoms (Co-SAs) deposited via immersion method on BFO and Ti-BFO-R nanostructures led to achieving outstanding O2 evolution at a rate of 16.11 and 23.89 mmol g−1 h−1, respectively, which is 153 and 227.5 times higher compared to BFO (in the presence of AgNO3), the highest O2 evolution observed for BFO-based materials to date. The successful deposition of Co-SAs is confirmed by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (AC HAADF-STEM) and X-ray absorption near-edge structure (XANES). The charge transfer investigations confirm the significance of Co-SAs on BFO-based photocatalysts for improved charge–carrier separation, transport, and utilization. This novel study validates the excellent role of Na2S2O8 as a sacrificial agent and Co-SAs as a cocatalyst for BFO-based nanostructures for efficient O2 evolution.  相似文献   
506.
Journal of Inorganic and Organometallic Polymers and Materials - During this report, the synthesis, characterization, medicinal, and molecular modeling of newly synthesized, bidentate sulfonamide...  相似文献   
507.
508.
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   
509.
The present study highlights a range of surface and volume extrudate patterns that can be detected during the extrusion flow of long-chain branched polymers. Thus, four linear low-density polyethylenes (LDPEs) have been extruded using a single-screw extruder coupled to an inline optical imaging system. The selected LDPEs are selected to outline the influence of molecular weight and long-chain branching on the types of melt flow extrusion instabilities (MFEI). Through the inline imaging system, space–time diagrams are constructed and analyzed via Fourier-transformation using a custom moving window procedure. Based on the number of characteristic frequencies, peak broadness, and whether they are surface or volume distortions, three main MFEI types, distinct from those typically observed in linear and short-chain branched polymers, are identified. The higher molecular weight, low long-chain branching LDPEs exhibited all three instability types, including a special type volume instability. Independently of the molecular weight, higher long-chain branching appeared to have a stabilizing effect on the transition sequences by suppressing volume extrudate distortions or limiting surface patters to a form of weak intensity type.  相似文献   
510.
A dual-network model (DNM) representing the topological characteristics of both the pore space and solid fraction of a packed bed was developed to study coupled incompressible water flow and heat transport from the pore-scale to mesoscale (μm-cm) with the consideration of temperature-dependent fluid viscosity. The DNM was validated and used to study the temperature and velocity at the pore scale and their effects on fluid flow and heat transfer. Then the pore volume of the DNM was varied to illustrate the effect of bed porosity on transport processes, quantifying the trade-off between flow conditions and heat transfer. This work demonstrates the ability of the DNM to simulate pore-scale fluid flow and heat transfer simultaneously, which can then be averaged over the entire simulation domain to approximate meso/macroscopic parameters efficiently in relation to the pore geometry.  相似文献   
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