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131.
Abstract

Sensitivity analysis of gas-phase chemistry is used for improving the diamond growth model. Performed consideration shows that the more careful choice of a set of chemical reactions, both gas-phase and surface, and of their parameters is required. It is concluded that the preliminary analysis of the sensitivity of the system to key parameters is welcome.  相似文献   
132.
Time domain topology optimization is applied to design pulse shaping filters. The objective function depends on the pulse envelope, which is extracted by utilizing the Hilbert transform. The gradients with respect to the topology optimization variables are derived, and the optimization methodology is demonstrated for pulse delaying and pulse splitting. The formulation is applicable for non-linear structures and signals consisting of broad range of frequencies.  相似文献   
133.
Water enables life and plays a critical role in biology. Considered as a versatile and adaptive component of the cell, water engages a wide range of biomolecular interactions. An organism can exist and function only if its self-assembled molecular structures are hydrated. It was shown recently that switching of AMP/ATP binding to the insulin-independent glucose transporter Human Erythrocyte Glucose Transport Protein (GLUT1) may greatly influence the ratio of bulk and bound water during regulation of glucose uptake by red blood cells. In this paper, we present the results on the hydration properties of AMP/ATP obtained by means of dielectric spectroscopy in aqueous solution and for fully ionized forms in solid amorphous films with the help of gravimetric studies.  相似文献   
134.
应用奇值分解反褶积压制震源产生的干扰   总被引:1,自引:1,他引:0  
1. Introduction Seismic sources generate various types of surface waves, depending on the near-surface environment and nature and the position of the source. Source-generated noise, such as air, refracted, guided waves, near-surface multiples, near-surfac…  相似文献   
135.
Booming progress in the materials science offers a huge choice of novel porous solids which may be used for adsorption transformation of low temperature heat. This communication gives an overview of original and literature data on several classes of materials potentially promising for this important application, namely, metalaluminophosphates (AlPOs, SAPOs, MeAPOs), metal-organic frameworks (MIL, ISE, etc.), ordered porous solids (MCM, SBA, etc.), porous carbons and various composites (SWSs, AlPO-Al foil). For the SWS composites, we briefly considered the recent trends in their developing, namely, usage of host matrices with uniform pore dimensions and binary salt systems. We hope that this review will give new impulses to target-oriented research on the novel adsorbents for AHT and may also be beneficial for further consolidating international activities in materials science and heat transformation applications.  相似文献   
136.
In the framework of the “ULTIMA” project, we use ultra cold superfluid 3He bolometers for the direct detection of single particle events, aimed for a future use as a dark matter detector. One parameter of the pulse shape observed after such an event is the thermalization time constant τ b . Until now it was believed that this parameter only depends on geometrical factors and superfluid 3He properties, and that it is independent of the nature of the incident particles. In this report we show new results which demonstrate that a difference for muon- and neutron events, as well as events simulated by heater pulses exist. The possibility to use this difference for event discrimination in a future dark matter detector will be discussed.   相似文献   
137.
ULTIMA is a project which proposes to use superfluid 3He as a sensitive medium for direct dark matter search. In this paper we report on new, detailed calibrations of our bolometric cells as a function of the magnetic field. An influence on the order of 20% on the peak height after an energy deposition is observed for magnetic fields up to 330 mT. Simultaneous measurements of neutron capture and heater events, releasing both a well defined energy, show that the effect is similar for both, and that it is possible to maintain a good calibration by an appropriate correction.   相似文献   
138.
Superfluid 3He–B is characterised by a very isotropic spin and orbit order parameter, which makes its dynamics very stable. Nevertheless, a strong instability of NMR precession was observed at cooling, and named “Catastrophic relaxation”. For years the mechanism of this instability remained unknown. Recent investigations have solved this problem. In this article we will show the history of catastrophic relaxation investigations and will describe the correct theory of this phenomenon.  相似文献   
139.
The article investigates the effect of thermal modification of porous carbon material (PCM), obtained from plant feedstock, on its morphology and fractal structure by small-angle X-ray scattering (SAXS) method. The analysis of the scattering intensity curves serve the basis for calculating the parameters of the PCM porous structure: the Porod constant, the Porod invariant, average pore radius, specific surface area, and mass and surface fractal dimensions. It has been found out that the PCMs obtained have fractal structure, formed from mass and surface fractals, the sizes of which increase at the growth of temperature and modification time.

PACS

81.05.Uw; 61.05.cf; 82.47.Aa  相似文献   
140.
Replacing halogenated solvents in the processing of organic solar cells by green solvents is a required step before the commercialization of this technology. With this purpose, some attempts have been made, although a general method is yet to be developed. Here, the potential of the Hansen solubility parameters (HSP) analysis for the design of green ink formulations for solution‐processed active layer in bulk heterojunction photovoltaic devices based on small molecules is demonstrated. The motivation of moving towards organic small molecules stems from their lower molecular weight and more definite structure which makes them more likely to be dissolved in a wider variety of organic solvents. In the first step, the HSP of selected active materials are determined, namely, the star‐shaped D‐π‐A tris{4‐[5′′‐(1,1‐dicyanobut‐1‐en‐2‐yl)‐2,2′‐bithiophen‐5‐yl]phenyl}amine N(Ph‐2T‐DCN‐Et)3 small molecule and fullerene derivative [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC70BM). Secondly, computer simulations based on HSP allow the prediction of suitable green solvents for this specific material system. The most promising green solvents, according to the simulations, are then used to fabricate solar cell devices using pristine solvents and two solvents mixtures. These devices show power conversion efficiencies around 3.6%, which are comparable to those obtained with halogenated solvents. This good performance is a result of the sufficient solubility achieved after a successful prediction of good (green) solvents.  相似文献   
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