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141.
Younes Hanifehpour Nina Saraei Sanaz Mokhtari Asl Sang Woo Joo 《Journal of Inorganic and Organometallic Polymers and Materials》2012,22(6):1271-1278
Two new nano mercury(II) coordination compounds, [Hg2(μ-L1)(μ-I)2I3]n (1) and [Hg(L2)(I)2] (2) {L1?=?(E)-N′-(pyridin-2-ylmethylene)isonicotinohydrazide and L2?=?(E)-N′-(1-(pyridin-2-yl)ethylidene)isonicotinohydrazide} have been synthesized by a sonochemical method. The new nano-structures were characterized by scanning electron microscopy, X-ray powder diffraction, elemental analysis and IR spectroscopy. The compounds were also characterized by single crystal X-ray diffraction and the results indicate a 1D fishbone-like structure containing dinuclear units for 1 and a mononuclear structure for 2. In coordination polymer 1, the two Hg(II) centers are four coordinate into a chain-axis and also in the terminal linkages. In complex 2, the Hg(II) center is four coordinate. The chains of polymer 1 interact with each other through π–π stacking interactions which create a 3D framework. 相似文献
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143.
Anis Younes Vincent Fontaine 《International journal for numerical methods in engineering》2008,76(3):314-336
The mixed hybrid finite element (MHFE) and the multipoint flux approximation (MPFA) methods are well suited for anisotropic heterogeneous domains since both are locally conservative and can handle general irregular grids. In this work, behaviours and performances of MHFE and MPFA methods are studied numerically for different heterogeneities and anisotropy factors on parallelograms and then on a more general quadrilateral grid. The superiority of MPFA in terms of accuracy and efficiency is clearly demonstrated for parallelogram grids. In the case of more general quadrilateral grids, MPFA becomes more central processing unit time consuming than MHFE. For high anisotropy factors, both methods give results with significant non‐physical oscillations. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
144.
Abdallah Younes Houari Sayah Mohamed Younes Adrian Samuila 《Particulate Science and Technology》2013,31(3):207-210
The objective of this work was to analyze the behavior of good conducting granules in a newly designed plate-type electrostatic separator. Commercial software was employed for the numerical analysis of the electric field generated by an original electrode configuration. This enabled the evaluation of the electric charge and forces on conducting particles. The trajectory of a single particle was calculated over a set of 1300 points. The simulated results show that the trajectories depend on the applied voltage, the radius, and the mass density of the granules. They were found in good agreement with the experiments carried out on a laboratory electrostatic separator. 相似文献
145.
K. Medles L. Dascalescu A. Tilmatine A. Bendaoud M. Younes 《Particulate Science and Technology》2013,31(2):163-171
This article aims at demonstrating the interest the design of experiment methodology might present for modeling and optimization of a typical electrostatic separation process. A classical 23 full-factorial design followed by a composite design were employed for carrying out experiments on the selective sorting of conductive and nonconductive particles contained in a granular mixture. The study was performed on a roll-type corona-electrostatic separator, with samples prepared from genuine electric cable wastes, composed of 5% copper and 95% PVC. The response function was the mass of the middling fraction collected after separation, the factors under investigation being the high-voltage level, the speed of the rotating roll electrode, and the angular position of the splitter between the copper and middling compartments of the collector. By using commercial design of experiments software, it was possible to estimate the effects of these factors and then derive the model of the process as a quadratic polynomial function. This model served at predicting the optimal set point of the process. The results reported support design of experiments methodology as an efficient tool for the optimization of industrial electrostatic separation processes. 相似文献
146.
Reported herein are the results of an analysis of the compatibility of three methods for quantifying the non‐adsorbed forms of reactive dyes, in an exhausted dyebath, of the type monochlorotriazine/β‐sulphatoethylsulphone used in dyeing cellulosic fibres (cotton). The first method is based on spectrophotometric analysis and involves measuring the absorbance of the residual dyebath (after the dyeing process), the second is based on colorimetric analysis and involves measuring the reflectance of the dyed fabric and the third is based on high‐performance liquid chromatography. The purpose of the latter is to identify and quantify the non‐adsorbed dye forms in the residual dyebath. The calculated exhaustion values unequivocally prove the reliability and compatibility of these methods. 相似文献
147.
Younes Hanifehpour Sanaz Mokhtari Asl Babak Mirtamizdoust Sang Woo Joo 《Journal of Inorganic and Organometallic Polymers and Materials》2012,22(4):923-928
A novel nano-rods cadmium(II) fluorine-substituted β-diketonate, [Cd(2,2′-bpy)(dfpb)2] (1), (2,2′-bpy = 2,2′-bipyridine; dfpb = 4,4-difluoro-1-phenyl-1,3-butandion) has been synthesized by a sonochemical method that produces the coordination compound with nano dimensions. The new nanostructure was characterized by scanning electron microscopy, X-ray powder diffraction (XRD) elemental analysis and IR spectroscopy. Compound 1 was structurally characterized by single crystal X-ray diffraction. The single-crystal structure of this complex shows that the coordination number of the CdII ions is six with two N-donor atoms from the 2,2′-bpy ligand and four O-donors from two dfpb. Self-assembly of the complex occurs through CH···F–C and π–π stacking interactions. The supramolecular features of 1 are controlled by weak directional intermolecular interactions. CdO nanoparticles were obtained by thermolysis of 1 at 180 °C with oleic acid as a surfactant. The average diameter of the nanoparticles was estimated by the Scherrer equation to be 20 nm. The morphology and size of the CdO samples were further observed using SEM. 相似文献
148.
Younes Hanifehpour Babak Mirtamizdoust Arezou Rahnemaye Farzam Sang Woo Joo 《Journal of Inorganic and Organometallic Polymers and Materials》2012,22(5):957-962
Nano rods of a new 1D polymeric lead(II) complex containing the Pb2-(μ-N3)2 motif, [Pb(phen)(μ-N3)(μ-NO3)]n (phen?=?1,10-phenanthroline), has been synthesized by a sonochemical method. The new nano-structure was characterized by scanning electron microscopy, X-ray powder diffraction, elemental analyses and IR spectroscopy. A single crystalline material was obtained by applying a heat gradient to a solution of reagents. The single crystal X-ray data showed the coordination number of the Pb2+ ions to be eight (PbN4O4), with the Pb2+ ions having “stereo-chemically active” electron lone pairs; the coordination sphere was hemidirected. The chains of [Pb(phen)(μ-N3)(μ-NO3)]n interact with each other via π–π interactions to create a 3D framework. PbO nanoparticles were obtained by thermolysis of 1 at 180?°C with oleic acid as a surfactant. The average diameter of the nanoparticles was estimated to be 33?nm by the Scherrer equation. The morphology and size of the prepared PbO samples were further observed using SEM. 相似文献
149.
150.
Jean-Christophe Dupré Pascal Doumalin Younes Belrhiti Imad Khlifi Octavian Pop Marc Huger 《Journal of Materials Science》2018,53(2):977-993
This paper is devoted to the study of the fracture behaviour of two industrial refractory materials thanks to the development of a new technique of digital image correlation (DIC). DIC, already known as a helpful and effective tool for the measurement of displacement and deformation fields in materials, has been adapted to take into account displacement discontinuities as cracks. The material transformation, usually assumed homogeneous inside each DIC subset, is thus more complex, while each subset can be cut in two parts with different kinematics. By this way, it is possible to automatically find the fracture paths and follow the crack geometries (length, opening) during the loading with a higher spatial resolution than the one obtained by standard DIC. After having presented the principle of the new technique, its metrological performances are assessed from synthetic images and the choice of crack detection criterion is discussed. The capacity of this new technique is shown through a comparative study with standard DIC. Its application is led on magnesia-spinel refractory materials, specifically to highlight and to characterize the evolution of kinematic fields (displacement and strain) observed at the surface of sample during a wedge splitting test typically used to quantify the work of fracture. We show that refractories with aggregates of iron aluminate spinel present a fracture mechanism with crack branching and can dissipate more energy thanks to a longer crack network. 相似文献