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51.
The results of calculations using the kinetic models of material balance of methane–hydrogen, propane–propylene, butylene–divinyl, and isobutylene regions were presented. Together with the previously calculated ethylene region, these regions constitute the chemical-technological complex for cracking and pyrolysis gas processing. The final scheme of the chemical-technological complex with indication of all of its inlet and outlet flows and connections between the material and recirculation flows between regions was presented. The production capacities of reactor elements were determined for all the desired products of the chemical-technological complex.  相似文献   
52.
Prostate cancer (PC) is the most common cancer in men and the second leading cause of cancer-related death worldwide. Many therapeutic advances over the last two decades have led to an improvement in the survival of patients with metastatic PC, yet the majority of these patients still succumb to their disease. Antiagiogenic therapies have shown substantial benefits for many types of cancer but only a marginal benefit for PC. Ongoing clinical trials investigate antiangiogenic monotherapies or combination therapies. Despite the important role of angiogenesis in PC, clinical trials in refractory castration-resistant PC (CRPC) have demonstrated increased toxicity with no clinical benefit. A better understanding of the mechanism of angiogenesis may help to understand the failure of trials, possibly leading to the development of new targeted anti-angiogenic therapies in PC. These could include the identification of specific subsets of patients who might benefit from these therapeutic strategies. This paper provides a comprehensive review of the pathways involved in the angiogenesis, the chemotherapeutic agents with antiangiogenic activity, the available studies on anti-angiogenic agents and the potential mechanisms of resistance.  相似文献   
53.
To determine the dynamic forces acting on vehicle components a vehicle-structure-road interaction is considered. Coupled interaction was modelled using a flexible bridge-like thin beam structure with four and six Degree of freedom (DOF) half car models. In addition to the flexible structure, the road conditions were added to the model as random and non-random surface irregularities. A coupled equation of motion of the whole system was derived using Lagrange equations, and converted to a first-order state-space equation and then solved using the fourth-order Runge-Kutta method. Besides the dynamic forces, the effects of the vehicle speed, bridge flexibility, tire stiffness, random or non-random road irregularities on the passenger comfort are widely investigated. The results obtained were compared by several early VBI (Vehicle-bridge-interaction) studies in the literature and proved accurate with a 5 % difference.  相似文献   
54.
This article presents a microfluidic device which integrates autonomous serial immunofluorocytometry binding reactions of cytometric beads with fluorescence detection and quantification in a continuous flow environment. The microdevice assay is intended to alleviate the extensive benchwork and large sample volumes used when conducting traditional immunoassays, without requiring complex external controls. The technology is based on the miniaturization and automation of the serial processing steps of an antigen sandwich immunoassay, with integrated fluorescence detection using paramagnetic microbeads. The continuous flow design may enable temporal tracking of time-varying protein concentrations in a continuously infused sample for clinical applications, specifically for monitoring inflammation marker proteins in blood produced during cardiac surgeries involving cardiopulmonary bypass (CPB) procedures. The device operation was first validated via a single incubation device which measured the concentration of a fluorescently labeled biotin molecule using streptavidin-coated paramagnetic cytometric beads. Subsequently, a dual incubation device was tested with samples of the anaphylatoxin complement protein C3a, and was shown to be capable of differentiating between samples at typical systemic concentrations of the protein (1–5 μg/ml), with very low sample usage (<6 μl/h). It is believed that this continuous flow, automated microimmunosensor technology will be a platform for high sample rate immunoassays capable of tracking and more thoroughly characterizing the systemic inflammation process, and may aid in the development of better treatment options for systemic inflammation during and after CPB.  相似文献   
55.
Theoretical Foundations of Chemical Engineering - This paper completes our work on calculation of a chemical-technological complex for coprocessing cracking and pyrolysis gases on the basis of a...  相似文献   
56.
The corrosion rates of the Mg alloys immersed in 3.5 wt% NaCl solution saturated with Mg(OH)2 were in the following increasing order: WE43B (0.23 mm/y) < EV31A (0.88 mm/y) < pure‐Mg (1.6 mm/y) < ZE41A (8.5 mm/y). The average corrosion rate for WE43B was somewhat lower than the intrinsic corrosion rate of Mg as shown by high‐purity Mg, attributed to (a) no corrosion acceleration by the small second phase particles, and (b) a more protective surface film. The high corrosion rates of ZE41A were attributed to the presence of a coarse semicontinuous T‐phase, which served as strong cathodic sites.  相似文献   
57.
Influence of boron-doping on the superconducting properties of (Bi,Pb)-2223 HTS ceramics prepared in an alumina crucibles has been investigated. X-ray diffraction, resistivity, and AC susceptibility measurements were performed on the undoped and boron-doped compounds. Obtained results have shown that B2O3 addition in the Bi1.7Pb0.3Ca2Sr2Cu3O y precursor enhances the formation of high-T c phase. The boron-doped samples with starting composition Bi1.7Pb0.3Ca2Sr2Cu3B x O y (x=0.05 and 0.5) reveal significant improvement in the zero resistivity temperature compared to the undoped sample (from 72 K up to 100 K). Boron-doping level x=1.5 results in a substantial degradation of the (Bi,Pb)-2223 phase.  相似文献   
58.
The synthesis of silver nanoparticles employing a shadow-dried Stevia rebaudiana leaf extract in AgNO3 solution is reported. Transmission electron microscopy and X-ray diffraction inspections indicate that nanoparticles are spherical and polydispersed with diameters ranging between 2 and 50 nm with a maximum at 15 nm. Ultraviolet–visible spectra recorded against the reaction time confirms the reduction of silver nanoparticles indicating that the formation and the aggregation of nanoparticles take place shortly after the mixing, as they persist concurrently with characteristic times of 48.5 min and 454.5 min, respectively. Aggregation is found to be the dominant mechanism after the first 73 min. Proton nuclear magnetic resonance spectrum of the silver nanoparticles reveals the existence of aliphatic, alcoholic and olefinic CH2 and CH3 groups, as well as some aromatic compounds but no sign of aldehydes or carboxylic acids. Infrared absorption of the silver nanoparticles suggests that the capping reagents of silver and gold nanoparticles reduced in plant extracts/broths are of the same chemical composition of different ratios. Ketones are shown to play a somehow active role for the formation of nanoparticles in plant extracts/broths.  相似文献   
59.
The oxidation processes are studied of untreated and radiation-oxidation preliminary treated (in an H2O2 solution at room temperature) zirconium specimens in contact with water by reflection-absorption infrared spectroscopy. A comparison is performed of their kinetic characteristics. Passivation of the metal surface is revealed as evidence of the surface oxide layer.  相似文献   
60.
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