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41.
42.
The financial services industry today produces and consumes huge amounts of data and the processes involved in analysing these data have large and complex resource requirements. The need to analyse the data using such processes and get meaningful results in time, can be met only up to a certain extent by current computer systems. Most service providers attempt to increase efficiency and quality of their service offerings by stacking up more hardware and employing better algorithms for data processing. However, there is a limit to the gains achieved by using such an approach. One viable alternative would be to use emerging technologies such as the Grid. Grid computing and its application to various domains have been actively studied by many groups for more than a decade now. In this paper we explore the use of the Grid in the financial services domain; an area which we believe has not been adequately looked into.  相似文献   
43.
Containerless tube extrusion has been investigated with commerically pure titanium at room temperature and a strain rate of 0.07 s-1 using 20 conical dies of five different strains and four different angles with MoS2 lubricant. Theoretical punch pressures have been calculated using appropriate equations from slab analysis of the process and compared with experimentally determined punch pressures. It is found that there exists an optimum angle at which the punch pressure is the least at a given strain.  相似文献   
44.
In the present study, green synthesis and cost effective approach of silver nanoparticles using wild medicinal mushroom Ganoderma applanatum (Pers.) Pat. from Similipal Biosphere Reserve, Odisha, India is reported. The biosynthesised AgNPs were characterised using UV‐visible spectroscopy, particle analyser and scanning electron microscopy studies. It was found by dynamic light scattering analysis, that the average size and charges of the AgNPs were 133.0 ± 0.361 nm and −6.01 ± 5.30 mV, respectively. Moreover, the Fourier transform infrared study was also conducted to identify the biomolecules or functional groups responsible for the reduction of Ag and stabilisation of the AgNPs. The potential biomedical application with reference to antimicrobial activity of the synthesised AgNPs was investigated against some pathogenic microorganisms viz. Escherichia coli, Bacillus subtilis, Staphylococcus epidermidis, Vibrio cholerae, Staphylococcus aureus and Shigella flexneri.Inspec keywords: antibacterial activity, biomedical materials, nanomedicine, nanofabrication, materials preparation, ultraviolet spectra, visible spectra, scanning electron microscopy, Fourier transform infrared spectra, molecular biophysics, reduction (chemical), biochemistry, microorganisms, silver, nanoparticlesOther keywords: green synthesis, antimicrobial activity, silver nanoparticles, wild medicinal mushroom, Ganoderma applanatum Pat, Similipal Biosphere Reserve, Odisha, UV‐visible spectroscopy, particle analyser, scanning electron microscopy, dynamic light scattering analysis, Fourier transform infrared study, biomolecules, functional groups, silver reduction, AgNP stabilisation, biomedical application, pathogenic microorganisms, Escherichia coli, Bacillus subtilis, Staphylococcus epidermidis, Vibrio cholerae, Staphylococcus aureus, Shigella flexneri, Ag

Abbreviations

AgNPs
‐ Silver Nanoparticles
SPR
‐Surface plasmon resonance
AgNO3
‐Silver nitrate
nm
‐ Nanometer
mm
‐Milimetre
  相似文献   
45.
Meta-schedulers map jobs to computational resources that are part of a Grid, such as clusters, that in turn have their own local job schedulers. Existing Grid meta-schedulers either target system-centric metrics, such as utilisation and throughput, or prioritise jobs based on utility metrics provided by the users. The system-centric approach gives less importance to users’ individual utility, while the user-centric approach may have adverse effects such as poor system performance and unfair treatment of users. Therefore, this paper proposes a novel meta-scheduler, based on the well-known double auction mechanism that aims to satisfy users’ service requirements as well as ensuring balanced utilisation of resources across a Grid. We have designed valuation metrics that commodify both the complex resource requirements of users and the capabilities of available computational resources. Through simulation using real traces, we compare our scheduling mechanism with other common mechanisms widely used by both existing market-based and traditional meta-schedulers. The results show that our meta-scheduling mechanism not only satisfies up to 15% more user requirements than others, but also improves system utilisation through load balancing.  相似文献   
46.
Current generation carbon–carbon (C–C) and carbon–silicon carbide (C–SiC) materials are limited to service temperatures below 1800 °C and materials are sought that can withstand higher temperatures and ablative conditions for aerospace applications. One potential materials solution is carbon fibre-based composites with matrices composed of one or more ultra-high temperature ceramics (UHTCs); the latter are intended to protect the carbon fibres at high temperatures whilst the former provides increased toughness and thermal shock resistance to the system as a whole. Carbon fibre–UHTC powder composites have been prepared via a slurry impregnation and pyrolysis route. Five different UHTC compositions have been used for impregnation, viz. ZrB2, ZrB2–20 vol% SiC, ZrB2–20 vol% SiC–10 vol% LaB6, HfB2 and HfC. Their high-temperature oxidation resistance has been studied using a purpose built oxyacetylene torch test facility at temperatures above 2500 °C and the results are compared with that of a C–C benchmark composite.  相似文献   
47.
The effects of silver doping on the magnetotransport and thermopower of La1?x Ag x MnO3 (0.05≤x≤0.30) have been investigated. For the sample with x=0.05, temperature dependent resistivity exhibits an insulating behavior, while thermopower is found to be large and negative over the measured temperature range. An increase in the Ag doping enhances the conductivity and shifts the metal-insulator transition temperature toward high temperature side. The low temperature thermopower data has been explained in terms of diffusion, magnon drag, and phonon drag effects and found that the magnon drag effect dominates in this region. Finally, the electrical transport in the high temperature region has been analyzed by using adiabatic small polaron hopping mechanism.  相似文献   
48.
Fracture toughness tests were conducted on a Ti-62222 (titanium alloy) sheet being considered for use in high temperature aircraft applications in the as received condition and after exposing the pre-cracked specimens to a sustained stress intensity, K, level between 55 and 60.5 MPa for 200 h at 350°C. It was concluded that the fracture toughness does not degrade as a result of exposure to high temperature and the K levels in this material. The tensile strength in the exposed condition also remained the same as in the as received condition.  相似文献   
49.
ABSTRACT

The aim of the present study was to obtain cross-linked calcium-gellan beads containing diclofenac sodium as model drug, using full 33 factorial design. Drug quantity, pH of cross-linking solution, and speed of agitation were selected as variables for factorial design. The resultant beads were evaluated by scanning electron microscopy (SEM), percent yield, entrapment efficiency, micromeritic properties, swelling and drug release studies. The drug-loaded beads were spherical with size range of 0.85–1.8 mm. Percent yield and entrapment efficiency of various batches were in the range of 86.48–98.28% w/w and 72.52–92.74% w/w, respectively. Calcium-gellan beads containing diclofenac sodium showed pH-dependent swelling and drug release properties. Swelling and drug release were significantly higher in pH 7.4 phosphate buffer than 0.1N HCl. The swelling ratio for beads was up to 22 and 3 for phosphate buffer and 0.1N HCl, respectively. Cumulative diclofenac sodium release from calcium-gellan beads was 12–35% in 0.1N HCl within 2 h, whereas complete drug release was observed within 3–4 h in pH 7.4 phosphate buffer.  相似文献   
50.
The present study was undertaken to investigate the protective effect of tetrahydrocurcumin (THC) and chlorogenic acid (CGA) against streptozotocin (STZ)–nicotinamide (NA)-induced type 2 diabetes in adult Wistar rats. Diabetes was induced in experimental rats weighing 180–220 g, by a single intraperitoneal (i.p.) injection of STZ (45 mg/kg BW), 15 min after the (i.p.) administration of NA (110 mg/kg BW). THC (80 mg/kg BW) and CGA (5 mg/kg BW) were orally administered to diabetic rats for a period of 45 days. Fasting plasma glucose, glycosylated haemoglobin (HbA1C), thiobarbituric acid reactive substances (TBARS) and lipid hydroperoxides (LOOH) were significantly increased, whereas insulin, total haemoglobin (Hb), non-enzymic antioxidants (reduced glutathione (GSH), vitamin C, vitamin E and ceruloplasmin) were decreased significantly in diabetic rats. Though the diabetic rats treated with THC and CGA individual exerts beneficial effects in all the biochemical parameters in (STZ)-induced diabetic rats. The combined treatment with THC and CGA normalized all the above-mentioned biochemical parameters in STZ-induced diabetic rats. Normal pancreatic histological architecture in THC and CGA treated diabetic rats revealed that these phytochemical exert higher degree of protection when administered in combination than single treatment of individual compounds.  相似文献   
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