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51.
Reproducibility is a desirable characteristic of any experimental work in computer science. In this paper, we reproduce the results in the paper, “A parallel connectivity algorithm for de Bruijn graphs in metagenomic applications”, for verifying their claims on the speed and scalability of their algorithm. We first state the claims made in the original paper. Then, we describe our hardware and software setup used for the reproducibility task, followed by the steps taken to setup the proposed algorithm and profiling software. Lastly, we present the results obtained from our experiments and show that we are able to reproduce most of the claims made in the original paper. 相似文献
52.
The effect of synthesis method on optical and photoconducting properties of titanium dioxide (TiO2) nanoparticles has been investigated. Sol–gel and co-precipitation methods have been employed to prepare pure anatase phased TiO2 nanoparticles calcinated at different temperatures below 500 °C. The optimized value of average crystallite size is within the range of 19−21 nm for a common calcination temperature of 400 °C for both the methods. The redshift in optical band gap of 0.9 eV has been observed for the sample synthesized by co-precipitation method with respect to the sol–gel method. The photoluminescence spectrum exhibits broad visible emission in both routes of synthesis while photoconductivity shows fast growth and decay of photocurrent in TiO2 prepared by co-precipitation method as compared to TiO2 prepared by the sol–gel method under visible illumination. Crystal structure based Rietveld refinement of X-ray diffraction data, scanning electron microscopy as well as photoluminescence and photoconductivity measurements were performed to characterize nanocrystalline anatase TiO2. 相似文献
53.
《Journal of the European Ceramic Society》2014,34(10):2351-2361
Sandwich specimens were prepared by firing a thin inter-layer of porous La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) to bond a thin tetragonal yttria-stabilised zirconia (3YSZ) beam to a thick 3YSZ substrate. Fracture of the joint was evaluated by introducing a wedge between the two YSZ adherands so that the stored energy in the thin YSZ cantilever beam drives a stable crack in the adhesive bond. It was found that the extent of adhesive fracture increased with firing temperature and decreased with LSCF layer thickness. The adhesive failures were mainly at the interface between the LSCF and the thin YSZ beam and FEM modelling revealed that this is due to asymmetric stresses in the LSCF. The intrinsic adhesive fracture toughness of the LSCF/YSZ interface was estimated to be 11 J m−2 and was not firing temperature dependent within the temperature range investigated. 相似文献
54.
Nanostructured tungsten carbide particles were successfully synthesized by metal-organic chemical vapor deposition in a spouted bed followed by carburization in CH4/H2 atmosphere in the temperature range 700–900 °C. The carburization process was a little bit complex, which involved the coating of carbon on the outer surface of the decomposed W(CO)6 precursor particles and then followed by carbon diffusion into the particles, leading to the formation of nanostructured WC via an intermediate metastable phase W2C. The carbon deficient phase W2C was formed initially at lower carburization temperature and then transformed to stable WC phase by increasing the temperature and holding time. 相似文献
55.
Experimental phase diagram of the dodecane–tridecane system as phase change material in cold storage
Integrating thermal storage with phase change materials (PCMs) in refrigeration and air conditioning processes enables energy performance improvements. Herein, the experimental phase diagram of the alkane system dodecane–tridecane (C12H26–C13H28) is evaluated to find PCMs for freezing applications. For that, the temperature-history method was coupled with a Tammann plot analysis. The obtained C12H26–C13H28 phase diagram indicated a congruent minimum-melting solid solution and polymorphs. The minimum-melting liquidus and the polymorphs identified here agree with previous literature. However, the system does not represent a eutectic, as previously was proposed. The minimum-melting composition is here identified within 15–20 mol% C13H28 compositions. The 17.7 mol% C13H28 is the narrowest minimum-melting composition among those analyzed, melting and freezing between −16 and −12 °C and between −17 and −15 °C, with the enthalpies 185 kJ kg−1 and 165 kJ kg−1; no supercooling; and only minor hysteresis. Hence, this blend has potential as a PCM in freezing refrigeration applications. 相似文献
56.
《能源学会志》2014,87(4):372-382
Recent technologies have been introduced for gas turbine engine to meet with stringent emission regulations. One of the technologies is to introduce recirculation in the combustion zone to control the residence time and mixing by help of swirling flow. Effect of variation in geometric parameters and inlet mass flow of swirler have been examined in this study by help of CFD. Detailed design methodologies have been proposed in this study to design a series of axial swirler with different vane angles and vane numbers. Substantial variation in swirler performance has been observed by changing vane angle, vane number and mass flow. Four different types of axial and radial velocity profiles have been observed. Turbulence distribution pattern shows double peaks at all positions and reduces with increasing axial distance. 相似文献
57.
This study proposes a whole life asset-supply chain optimization model for integration of biomass boilers into non-domestic (non-residential) buildings, under a renewable heat incentive scheme in the UK. The proposed model aims at identifying the optimal energy generation capacities and schedules for biomass and backup boilers, along with the optimal levels of biomass ordering and storage. The sensitivity of these decisions are then analyzed subject to changes in source, types and pricing of biomass materials as well as the choice of technologies and their cost and operational performance criteria. The proposed model is validated by applying it to a case study scenario in the UK. The results indicate that a Renewable Heat Incentive scheme could incentivize the adoption of biomass boilers, with a 3 to 1 ratio for biomass and backup boilers' utilization. As such, the findings from this study will be useful for industry managers, tasked with the decision of which biomass boiler system to utilize, considering the support from RHI. On the other hand, it is shown that RHI does not provide encouragement for efficiency when it comes to the choice of biomass technologies and fuels. This presents itself as a major implication for the success and sustainability of the UK government's renewable heat incentive scheme. 相似文献
58.
《Journal of the European Ceramic Society》2014,34(9):2117-2121
Undoped and 0.5 mol% Ce-doped LiF–LiYF4 eutectic crystals were grown by the micro-pulling-down method at different growth rates. The SEM images of all the eutectic crystals showed LiF with rod-like structure in the LiYF4 matrix. The diameter of the rod phase systematically decreased with the increase of the growth rate. The radioluminescence spectra of cerium doped crystal under alpha-ray excitation showed emission peak at 325 nm related to Ce3+ 5d-4f transition. The white part in the cathodoluminescence image is considered to be due to Ce3+ ion in LiYF4 phase, according to the scanning electron microscopy (SEM) image in the same region. 相似文献
59.
Online data acquisition, data assimilation and integrated hydrological modelling have become more and more important in hydrological science. In this study, we explore cloud computing for integrating field data acquisition and stochastic, physically-based hydrological modelling in a data assimilation and optimisation framework as a service to water resources management. For this purpose, we developed an ensemble Kalman filter-based data assimilation system for the fully-coupled, physically-based hydrological model HydroGeoSphere, which is able to run in a cloud computing environment. A synthetic data assimilation experiment based on the widely used tilted V-catchment problem showed that the computational overhead for the application of the data assimilation platform in a cloud computing environment is minimal, which makes it well-suited for practical water management problems. Advantages of the cloud-based implementation comprise the independence from computational infrastructure and the straightforward integration of cloud-based observation databases with the modelling and data assimilation platform. 相似文献
60.
Solar still is one of the best solutions to solve water problem in remote arid areas. This device is not popular because of its lower productivity. One of the methods to increase the productivity is by decrease the volumetric heat capacity of the basin. A layer of water with wick material in the basin will increase the evaporation area and enhance the production.A basin type double slope solar still with mild steel plate was fabricated and tested with minimum mass of water and different wick materials like light cotton cloth, sponge sheet, coir mate and waste cotton pieces in the basin. Still with aluminium rectangular fin arranged in different configurations and covered with different wicks were also tested. It was found that, the still with light black cotton cloth is the effective wick material. The still with rectangular Aluminium fin covered with cotton cloth and arranged in length wise direction was more effective.The still was theoretically modeled. The variation in transmittance of the cover was considered in the proposed model. The total radiation on the covers was taken as input. Theoretical values of water and glass temperatures using proposed model were compared with theoretical values obtained by Dunkle model and actual experimental values. It was found that the theoretical production rate using the proposed model were close to the experimental. 相似文献