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91.
This paper presents two efficient flooding algorithms based on 1-hop neighbor information. In the first part of the paper, we consider sender-based flooding algorithms, specifically the algorithm proposed by Liu et al. In their paper, Liu et al. propose a sender-based flooding algorithm that can achieve local optimality by selecting the minimum number of forwarding nodes in the lowest computational time complexity O(n logn), where n is the number of neighbors. We show that this optimality only holds for a subclass of sender-based algorithms. We propose an efficient sender-based flooding algorithm based on 1-hop neighbor information that reduces the time complexity of computing forwarding nodes to O(n). In Liu's algorithm, n nodes are selected to forward the message in the worst case, whereas in our proposed algorithm, the number of forwarding nodes in the worst case is 11. In the second part of the paper we propose a simple and highly efficient receiver-based flooding algorithm. When nodes are uniformly distributed, we prove that the probability of two neighbor nodes broadcasting the same messageneighbor nodes broadcasting the same message exponentially decreases when the distance between them decreases or when the node density increases. The analytical results are confirmed using simulation. 相似文献
92.
M. Lakshmi Kantam Ujjwal Pal B. Sreedhar Suresh Bhargava Yasuhiro Iwasawa Mizuki Tada B.M. Choudary 《Advanced Synthesis \u0026amp; Catalysis》2008,350(9):1225-1229
The selective oxidation of various alcohols into their corresponding aldehydes and ketones was achieved by ruthenium species stabilized on the nanocrystalline magnesium oxide (NAP‐MgO) by the incorporation of choline hydroxide, a basic ionic liquid, in excellent yields. The procedure is simple, efficient and environmentally benign. The catalyst can be used for four cycles with almost consistent activity. 相似文献
93.
M.J.P. Naik J. Debbarma M. Saha A. Bhargava 《Materialwissenschaft und Werkstofftechnik》2020,51(3):368-374
Nowadays, the synthesis of graphene/ graphene oxide from graphite precursor using oxidizing agents is the most common procedure, but the direct synthesis of graphene or graphene oxide from a non-graphitic carbonaceous material without using inert atmosphere is really a great challenge. Besides, the chemistry behind the development of graphitic structure from a non-graphitic material during the thermal heating is still not clearly understood. In this research work, three agrowaste materials viz. rice husk, sugarcane bagasse and newspaper were selected and subjected to pyrolysis in presence of trace amount of air. The continued heating at the optimum temperature has resulted in aromatization and condensation along with the oxidation within the cellulosic structure of the agrowaste, which finally resulted in the formation of graphene oxide nanoflakes directly. The mechanism of formation of graphene oxide from these agrowaste materials was studied, which suggested that any carbonaceous waste materials can be converted to graphene oxide by optimizing the thermal heating conditions. 相似文献
94.
Sarma Rajkumar Bhargava Cherry Jain Shruti Kamboj Vikram Kumar 《Neural computing & applications》2021,33(14):8893-8922
Neural Computing and Applications - Recently established Harris Hawks optimization (HHO) has natural behaviour for finding an optimum solution in global search space without getting trapped in... 相似文献
95.
Mahesh Dhonde Kirti Sahu V. V. S. Murty Siva Sankar Nemala Parag Bhargava Sudhanshu Mallick 《Journal of Materials Science: Materials in Electronics》2018,29(8):6274-6282
Pure and Copper/Nitrogen (Cu/N)-codoped TiO2 photoanodes with various Cu concentrations are prepared via sol–gel route for the photoanode application in dye-sensitized solar cells (DSSCs). All the prepared samples are characterized by X-Ray Diffraction (XRD), X-Ray Photoelectron Spectroscopy (XPS), Scanning Electron Microscope (SEM), Transmission Electron Microscopy (TEM), UV–Vis spectroscopy (UV–VIS) and Electrochemical Impedance Spectroscopy (EIS). Addition of suitable amount of Cu and N content in TiO2 can alter its optical and electrical properties by extending absorption in the visible region and band gap reduction. The results show that some of the Ti sites are replaced by Cu atoms while O sites are occupied by N atoms. Upon adequate addition of Cu/N could lead to smaller particle size, higher specific surface area, increased dye adsorption and retarded charge carrier recombination. A significant improvement in the power conversion efficiency is observed in case of optimized 0.3 mol% Cu/N-doped TiO2 nanoparticles (NPs) based DSSC. This optimized 0.3 mol% Cu/N-doped photoanode accomplished a best power conversion efficiency of 11.70% with a short circuit current density of 23.41 mA cm?2 which is 41% higher than that of the pure TiO2 photoanode based DSSC (6.82%). 相似文献
96.
The static behavior of composites and sandwich plates in thermo-mechanical environment is investigated by a two dimensional (2D) FE model. An efficient higher-order zig-zag theory (HOZT) considering actual through-thickness temperature profile and a least square error (LSE) method to accurately predict the inter-laminar stresses is implemented in this model. The in-plane displacement field is obtained by superposing a cubically varying global displacement field on a zig-zag displacement field having different slopes at each layer. This plate theory represents parabolic through thickness variation of transverse shear stresses, which satisfy the inter-laminar continuity at the layer interfaces and zero transverse shear stress conditions at the top and bottom of the plate. In the present 2D finite element (FE) model, the first derivatives of transverse displacement have been treated as independent variables to circumvent the problem of C1 continuity associated with the above plate theory (HOZT). The accurate through-thickness distribution of temperature is obtained by using a linear zig-zag thermal lamination theory proposed by the authors by using the thermal conduction properties of different constituent layers in the thickness direction. The LSE method is applied at the postprocessing stage to accurately calculate the inter-laminar stresses by the 3D equilibrium equations of the plate problem, after in-plane stresses are calculated. The proposed combined FE model (HOZT+LSE) is implemented to analyze the static behavior of laminated composites and sandwich plates subjected to thermo-mechanical loadings. Many new results are also presented that should be useful for the future reference. 相似文献
97.
Singh Pradeep Kumar Bhargava Bharat Hong Wei-Chiang Angin Pelin 《Multimedia Tools and Applications》2022,81(24):34439-34445
Multimedia Tools and Applications - 相似文献
98.
The kinetics of reaction between HCl gas and terpenes (α-pinene, myrcene, camphene, Δ3-carene) and isoamylene (2-methyl-2-butene) were studied,The reactions of HCl with α-pinene and Δ3-carene were found to be zero order with respect to HCl and second order with respect to the olefin. TThe reactions between HCl and myrcene (in the presence of CuCl as a catalyst) and camphene were found to be first order with respect to HCl as well asThe absorption of HCl in 2-methyl-2-butene was found to be second order with respect to HCl and first order with respect to 2-methyl-2-butene. The valu 相似文献
99.
Alumina foams with porosity ranging between 50% and 92% were fabricated by foaming followed by coagulation of ovalbumin based aqueous slurries. Different combinations of ovalbumin–water mix and alumina loading provided a means to vary slurry viscosity over a wide range. Slurry viscosity influenced the foaming behavior leading to variation in microstructure and mechanical properties of alumina foams. Controlling the slurry viscosity resulted in controlled the total porosity, microstructures and mechanical properties. Mechanical properties were correlated with different micro-mechanical models. Both microstructure and mechanical properties agreed well as closed cell alumina foam due to presence of low percent area of interconnections. 相似文献
100.
Ab initio molecular dynamics studies have been carried out on the room temperature ionic liquid, 1,n-butyl,3-methylimidazolium hexafluorophosphate ([bmim][PF6]) and supercritical carbon dioxide mixture at room temperature and experimental density. Partial radial distribution functions
(RDF) for different sites have been computed to see the organization of CO2 molecules around the ionic liquid. Several partial RDFs around the carbon atom of CO2 molecule are compared to find out that the CO2 has specific interaction with a carbon atom present in the imidazolium ring. The CO2 is also found to be very well organized around the terminal carbon atom of the butyl chain. The partial RDFs for the oxygen
atoms around oxygen and carbon atoms of the CO2 suggests that there is very good organization of CO2 molecules around themselves even in the [bmim][PF6]-CO2 mixture. The instantaneous quadrupole moment tensor has been calculated for the anion and the cation. The ensemble average
of diagonal components of quadrupole moment tensor of the cation have finite values, whereas the off-diagonal components of
the cation and both the diagonal and off-diagonal components of the anion have the value of zero with a large standard deviation.
The CPMD studies performed on CO2 clusters reveals the greater tendency of the clusters with more CO2 units, to deviate from the linear geometry. 相似文献