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61.
Percutaneous coronary intervention (PCI) effectively treats obstructive coronary artery syndrome. However, 30–40% patients continue to have angina after a successful PCI, thereby reducing patient satisfaction. The mechanisms underlying persistent angina after revascularisation therapy are still poorly understood; hence, the treatment or guideline for post-PCI angina remains unestablished. Thus, this study aimed to investigate the mechanisms underlying effort angina in animals following myocardial ischaemia-reperfusion (I/R) injury. Phosphorylated extracellular signal-regulated kinase (p-ERK), a marker for painful stimulation-induced neuronal activation, was used for the investigation. After a forced treadmill exercise (FTE), the number of p-ERK-expressing neurons increased in the superficial dorsal horn of the I/R model animals. Moreover, FTE evoked hydrogen peroxide (H2O2) production in the I/R-injured heart, inducing angina through TRPA1 activation on cardiac sensory fibres. Notably, the treatment of a TEMPOL, a reactive oxygen species scavenger, or TRPA1−/− mice successfully alleviated the FTE-induced p-ERK expression in the dorsal horn. The production of H2O2, a reactive oxygen species, through physical exercise contributes to angina development following I/R. Hence, our findings may be useful for understanding and treating angina following revascularisation therapy.  相似文献   
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63.
The extraction of divalent manganese, cobalt, nickel and copper-thiocyanato anionic species from aqueous solutions by tricaprylmethylammonium chloride (R3R′NCl) in benzene has been investigated under different conditions. Both the aqueous and organic phases have been examined by spectrophotometry. Infrared spectro-photometry and measurements of water content, apparent molecular weight and magnetic moment have been applied to the organic extracts, and electron spin resonance experiments to the organic manganese(II)- and copper(II)-complexes. The mechanism of the extractions and the structures of the extracted complexes are discussed on the basis of the results obtained. As a result, it is found that although the extraction efficiency follows the order Co > Cu > Mn > Ni, the extraction of divalent transition metals is expressed as [M(NCS)4]2-(aq) + 2R3R′NNCS(org)→(R3R′N)2-[M(NCS)4](org) + 2NCS-(aq) in which M = Mn, Co, Ni and Cu. The extracted species of divalent manganese, cobalt and nickel give a tetrahedral Td symmetry, and the copper(II) species is in a distorted tetrahedron (point group D2d symmetry). In addition the species of nickel (II) extracted at low aqueous concentration exists as a complex (R3R′N)2[Ni(NCS)4(H2O)2] in an octahedral arrangement.  相似文献   
64.
Thermoacoustic effects of inviscid fluids   总被引:2,自引:0,他引:2  
Thermoacoustic effects of inviscid fluids are studied with the use of linearized hydrodynamic equations. The heat flux and the acoustic energy source due to acoustic waves are related to entropy oscillations due to irreversible processes, and are evaluated for a plane wave in a long cylindrical tube with the boundary condition that the local oscillation of the temperature is absent at the wall surface. The heat flux and acoustic energy source obtained in the standing wave approximation give qualitative explanations of heat pumping and similar experiments and stability limits.  相似文献   
65.
This paper proposes and demonstrates a method for multi-scale, multi-depth three-dimensional (3D) lithography. In this method, 3D molds for replicating microchannels are fabricated by passing a non-focused laser beam through an optical fiber, whose tip is immersed in a droplet of photopolymer. Line width is adjustable from 1 to 980 µm using eight kinds of optical fibers with different core diameters. The height of line drawing can be controlled by adjusting the distance between the tip of the optical fiber and a substrate. The surface roughness (Ra, Rz) of a single line and plane was evaluated. The method was employed to fabricate a 3D mold of a microchannel containing tandem chambers, which was then successfully replicated in PDMS. Multi-scale, multi-depth 3D lithography can provide a simple, flexible tool for producing PDMS microfluidic devices.  相似文献   
66.
The thermodynamic modeling of the LiCoO2-CoO2 pseudo-binary system, a positive electrode material of Li-ion batteries, was performed using the CALPHAD technique. The O3-LiCoO2 and the O1-CoO2 phases were described using the four-sublattice model with the formula (Li,V a)1/2(Li,V a)1/2(Co)1(O)2, and the three-sublattice model with the formula (Li,V a)1(Co)1(O)2. The H1_3 hybrid phase was treated as a non-stoichiometric compound. The thermodynamic quantities, such as the phase equilibria, formation enthalpies and cell voltage (vs. Li/Li+), were in agreement with data reported in the literature.  相似文献   
67.
A series of undrained cyclic torsional simple shear tests using hollow cylindrical torsional shear apparatus was carried out to investigate the dynamic shear moduli and damping properties of clayey specimens with various sand contents and plasticity indices. The clayey soils used were collected from various sites along the coast of west Japan. Among these clayey soils, a clay sample with intermediate plasticity and another with high plasticity were mixed with silica sand at different proportions in order to examine the dynamic properties of sand-clay mixtures. In addition, experiments were carried out on undisturbed and remolded natural clay specimens with various plasticities. The effects of plasticity, loading frequency and confining pressure on the strain dependent normalized shear modulus and damping ratio were examined. Based on the results, empirical correlations for predicting the normalized shear modulus and damping ratio of remolded sand-clay mixtures at various shear strain levels were proposed.  相似文献   
68.
The recovery of indan derivatives from polystyrene waste for the purpose of efficient utilization of plastic wastes was studied. An attempt was made to construct the apparatus, in which thermal decomposition of polystyrene and catalytic reaction of its decomposition products over silica–alumina catalyst could be controlled continuously at the same time. The reaction temperature for thermal decomposition of polystyrene in the upper part of a reactor tube was 420°C, while that for catalytic reaction of the thermal decomposition products in the bottom of a reactor tube was 300°C. These results indicated that the composition of thermal decomposition products of polystyrene could be controlled by the use of a flow reactor. The indan derivatives recovered were two 1-methyl-3-phenylindans, one 1-methyl-1-phenylindan, and 1-phenylindan. The yields of these indan derivatives were 20% of the weight of the liquid products recovered. On the basis of the results obtained in the present work, the most suitable reaction conditions to recover indan derivatives from polystyrene waste is discussed.  相似文献   
69.
The distribution of uranium(vi) and thorium(iv) between nitric acid solutions and solutions of tri-n-octyl phosphine oxide (TOPO) in kerosene has been investigated. The organic phases have been studied by infrared and nuclear magnetic resonance spectroscopy. Further the absorption spectra of both the aqueous and organic phases have been examined in the extraction of uranium(vi).  相似文献   
70.
The distribution of divalent manganese, cobalt, copper, zinc and cadmium between aqueous solutions of hydrochloric acid and/or lithium chloride and the solutions of tricaprylmethylammonium chloride (Aliquat-336, R3R′NCl) in benzene has been investigated under different conditions. It is found that the extraction of these metals by Aliquat-336 proceeds as MCl42?(aq) + 2 R3R′NCI(org) ? (R3R′N)2MCI4 (org) + 2 Cl?(aq). The extraction curves have been examined utilizing a modified chemical model on the basis of this equilibrium equation. In addition, the electronic, electron spin resonance and infrared spectral results suggest that all the complexes formed in the organic phases are in a tetrahedral arrangement.  相似文献   
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