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991.
Metal oxide nanoparticles and their composites with conducting polymers, specifically Polyaniline (PANI) were utilized for fabricating nanoscale supercapacitor (SC) electrode materials. In the present study, we have synthesized pristine Pr2O3, NiO, Co3O4 nanoparticles, binary PANI-Pr2O3, PANI-NiO, PANI-Co3O4, ternary Pr2O3–NiO–Co3O4, and quaternary PANI-Pr2O3–NiO–Co3O4 spherical core-shell nanocomposite using co-precipitation and ultra-sonication methods. The grown samples were characterized with different analytical techniques. The XRD pattern revealed that the as-synthesized products were crystalline with Pr2O3 hexagonal phase, NiO cubic phase, and Co3O4 cubic phase in pure and nanocomposites. The Williamson-Hall, Scherrer, and size-strain plot methods were employed to study the crystalline development and contribution of micro-strain. FTIR pattern exhibited the metal-oxygen and PANI bond vibrations. FE-SEM images shown the spherical core-shell shape morphology of quaternary nanocomposite. EDX evident the presence of praseodymium, cobalt, and nickel in synthesized samples. UV–vis spectroscopy confirmed the absorption in the visible region. The IV graphs showed a higher conductivity of quaternary nanocomposite. The cyclic voltammetry results revealed that the quaternary nanocomposite has a higher specific capacitance 500 Fg-1 as compared to binary nanocomposites 134 F g?1 (PANI-Pr2O3), 143 F g?1 (PANI-Co3O4), 256 F g?1 (PANI-NiO), and PANI (90.8 F g?1) at a scan rate of 5 m Vs?1. The GCD results also showed that the quaternary nanocomposite has a higher specific capacitance of 905 F g?1 at current density 1 A g?1 with maximum energy density and power density of 87.99 kWhkg-1 and 2.6 k W kg?1, respectively. The EIS curve also confirmed that the quaternary nanocomposite has a lower polarization resistance (Rp) and solution resistance (Rs). The higher capacitance of quaternary nanocomposite can facilitate ion transfer, and the formation of its core-shell structure flourish to enhance surface-dependent electrochemical properties. Furthermore, this study gives a novel research idea to manufacture electrode materials for supercapacitors.  相似文献   
992.
Membrane technology has emerged as a leading tool worldwide for effective CO2 separation because of its well-known advantages, including high surface area, compact design, ease of maintenance, environmentally friendly nature, and cost-effectiveness. Polymeric and inorganic membranes are generally utilized for the separation of gas mixtures. The mixed-matrix membrane (MMM) utilizes the advantages of both polymeric and inorganic membranes to surpass the trade-off limits. The high permeability and selectivity of MMMs by incorporating different types of fillers exhibit the best performance for CO2 separation from natural gas and other flue gases. The recent progress made in the field of MMMs having different types of fillers is emphasized. Specifically, CO2/CH4 and CO2/N2 separation from various types of MMMs are comprehensively reviewed that are closely relevant to natural gas purification and compositional flue gas treatment  相似文献   
993.
994.
Multimedia Tools and Applications - In the context of video-based image classification, image annotation plays a vital role in improving the image classification decision based on it’s...  相似文献   
995.
Malnutrition is directly linked to the economic and social living standard of the people. It is the major cause of morbidity and mortality among the children, especially in the developing countries. The world population is projected to grow to around 9 billion by 2050 which will further escalate malnutrition. Snacks are becoming more and more popular and have a strong association with nutritional status of the young population. Extruded snacks have very low moisture (4–6%) and water activity (0.138) making them shelf stable. Shelf stable, nutrient dense products deemed to be ideal to alleviate malnutrition in the developing world. It is important to consider these healthy snacks for the provision of macro and micronutrients especially to the nutritionally vulnerable segment of population. Modern extrusion technologies have paved the way to use various nutrient-rich constituents to make attractive products. Analysis of supercritical fluid extrusion processed snacks has resulted in superior physical and textural properties while retaining the added macro and micronutrients. Nutrient-rich snacks produced through extrusion processing have been used for nutrition interventions along with community-based educational campaigns to mitigate malnutrition. This literature pertains the prevalence of malnutrition along with the usefulness of healthy extruded snacks against malnutrition.  相似文献   
996.
JOM - The separation of Cr-enriched α′ phase in Fe-(25–45) at.% Cr alloys is studied from the metastable region to the unstable region. The three-dimensional phase-field...  相似文献   
997.
Room-temperature, high-sensitivity, and broadband photodetection up to the shortwave infrared (SWIR) region is extremely significant for a wide variety of optoelectronic applications, including contamination identification, thermal imaging, night vision, agricultural inspection, and atmospheric remote sensing. Small-bandgap semiconductor-based SWIR photodetectors generally require deep cooling to suppress thermally generated charge carriers to achieve increased sensitivity. Meanwhile, the photogating effect can provide an alternative way to achieve superior photosensitivity without the need for cooling. The optical photogating effect originates from charge trapping of photoinduced carriers at defects or interfaces, resulting in an extremely high photogain (106 or higher). Here, a highly sensitive SWIR hybrid photodetector, fabricated by integrating an organic charge transfer complex on a graphene transistor, is reported. The organic charge transfer complex (tetrathiafulvalene–chloranil) has an exceptional low-energy intermolecular electronic transition down to 0.5 eV, with the aim of achieving efficient SWIR absorption for wavelengths greater than 2 µm. The photogating effect at the organic complex and graphene interface enables an extremely high photogain and a high detectivity of ≈1013 Jones, along with a response time of 8 ms, at room temperature for a wavelength of 2 µm.  相似文献   
998.
999.
A strategy of tailoring the ceramic cathode composite is presented to improve the performance of proton-conducting solid oxide fuel cells (SOFCs) prepared by a one-step co-firing process. Comparing to the conventional way of using BaCe0.7Zr0.1Y0.2O3-δ (BCZY) in the composite cathode for BCZY-electrolyte based cells, the replacement of BCZY by BaZr0.8Y0.2O3-δ (BZY) mitigates the reaction between the two ceramic phases in the composite cathode during the co-firing process and also keeps the cathode with sufficient porosity for ample gas diffusion which could assist in adequate cathode reactions. As a result, the BCZY-electrolyte based cell with Sm0.5Sr0.5CoO3-δ (SSC)-BZY composite cathode shows a power output of 300?mW?cm?2 at 600?°C, which is the largest ever reported for proton-conducting SOFCs prepared by a one-step co-firing process. The strategy of tailoring the composite cathode offers both small ohmic resistance and polarization resistance, providing a promising way to develop single-step co-fired proton-conducting SOFCs.  相似文献   
1000.
Owing to release of software in multiple releases, code changes take place in software. Because of this added complexity in software, the testing team may be unable to correct the fault upon detection, leaving the actual fault to reside in the software, termed as imperfect debugging or there may be replacement of original fault by other fault, leading to error generation. Many other factors exist that affect the testing phase of software like strategies of testing, test cases, skill, efficiency, and learning of testing team. All these factors cannot be kept stable during the whole process of testing. They may change at any time moment causing the background processes to experience change, which is known as change‐point. Keeping all these critical testing environment factors under consideration, a new software reliability growth model has been proposed, which is derived from an non homogenous Poisson process (NHPP)based unified scheme for multi‐release two‐stage fault detection/observation and correction/removal software reliability models. The developed model is numerically illustrated on tandem data set for four releases.  相似文献   
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