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991.
The effect of rosemary extract, chitosan and α-tocopherol, added individually or in combination, on lipid oxidation and colour stability of frozen (−18 °C) beef burgers stored for 180 days was investigated. The burgers’ lipid oxidation and appearance were evaluated through measurement of primary (conjugated dienes and peroxide value) and secondary (malondialdehyde) oxidation products, together with visual assessment and instrumental measurement of colour. Chitosan alone and in combination with either rosemary or α-tocopherol had the best antioxidative effect (P ? 0.05) compared to individual use of rosemary or α-tocopherol, while the best results were obtained with the combination of chitosan and rosemary. The differences of antioxidative effects, however, between individual use of rosemary or α-tocopherol as compared to the controls were also significant (P ? 0.05). Chitosan added individually or in combination with either rosemary or α-tocopherol had also a noteworthy effect on the burgers’ appearance as it contributed to red colour retention for a much longer period (P ? 0.05) compared all other treatments and the controls. In conclusion, the best antioxidative effects were obtained with the combination of chitosan and rosemary extract.  相似文献   
992.
An exact, analytical solution to the problem of point-source radiation in the presence of a sphere with an eccentric spherical inclusion has been obtained by combined use of the dyadic Green's function formalism and the indirect mode-matching technique. The end result of the analysis is a set of linear equations for the vector wave amplitudes of the electric Green's dyad. The point source can be anywhere, even within the aforesaid nonspherical body, and there is no restriction with regard to the electrical properties in any part of space. Several checks confirm that this solution obeys the energy conservation and reciprocity principles. Numerical results are presented for an electric Hertz dipole radiating from within an acrylic sphere, which contains an eccentric spherical cavity.  相似文献   
993.
Digital clubbing due to secondary hyperparathyroidism has been described as an unusual complication among patients with chronic kidney disease undergoing maintenance hemodialysis therapy. Although the pathogenesis of digital clubbing is unknown, certain growth factors such as platelet-derived growth factor and hepatocyte growth factor have been associated with this clinical syndrome. Two patients of our renal unit population presented this unique clinical feature bilaterally, among the other clinical findings of severe secondary hyperparathyroidism. Both patients were subjected to parathyroidectomy. Histological examination revealed diffuse hyperplasia of parathyroid glands. Despite the improvement of clinical symptoms and laboratory findings of secondary hyperparathyroism after parathyroidectomy, digital clubbing remained unchanged.  相似文献   
994.
995.
The effect of smoking on the proximate composition, chemical parameters and microbial loads of farmed gilthead sea bream (Sparus aurata L.), as well as the sensory attributes of the smoked product were investigated. The process reduced the moisture content and the total aerobic count and increased the protein, lipids and total volatile basic nitrogen content and the thiobarbituric acid number . The values of the last two parameters were much lower than acceptable limits reported in the literature references for smoked fish products. No effect was noted on the fatty acid composition of total lipids. The new product was highly acceptable to laboratory and consumer panels.Kyriakos Vareltzis deceased  相似文献   
996.
Nanometer-scaled liposomes are used frequently for research, therapeutic, and analytical applications as carriers for water-soluble molecules. Recent technical advances allow the monitoring of single liposomes, which provides information on heterogeneous properties that were otherwise hidden due to ensemble averaging. Recent observations demonstrated that the efficiency of entrapping water-soluble molecules increases with decreasing vesicle size. The molecular mechanism behind this observation is not clear, but enhanced molecule-membrane interactions due to the increase of the surface area-to-volume ratio could play an important role. To investigate this hypothesis, we extended our single liposome assay based on confocal fluorescence imaging by implementation of fluorescence anisotropy. This combination has not been widely exploited, and confocal fluorescence anisotropy imaging in particular has seldom been used. We investigated different small dye molecules and were able to determine if these molecules interact or not with the liposome membrane. We confirm the liposome size-dependent entrapment of molecules whereas the molecule-membrane interactions appear to be independent of liposome size. Our fluorescence anisotropy assay can be used as a general method to investigate molecule-membrane interactions or molecule-molecule interactions in a high-throughput manner in nanometer-scaled containers like liposomes.  相似文献   
997.
The commonly used CdS/i-ZnO buffer system in Cu(In,Ga)Se2 (CIGS) thin-film solar cells was substituted by ZnS/(Zn,Mg)O. ZnS has a higher transmission in the short wavelength range due to the higher bandgap energy Eg = 3.7 eV compared to CdS with Eg = 2.4 eV. Unfortunately, in our experiments the resulting gain in short-circuit current density jSC as the result of reduced absorption losses in the blue wavelength region is mostly accompanied by a decrease in open-circuit voltage VOC of the devices with ZnS buffer. This contribution discusses possible explanations for the systematically lower open-circuit voltages of the devices with a ZnS buffer layer.The carrier collection properties of the devices with a ZnS buffer were investigated by electron beam induced current measurements in the junction configuration. The maximum of the collection probability for ZnS cells is located in the CIGS bulk and not near the buffer/CIGS interface like for solar cells with CdS buffer. Additionally, we observed a larger space charge width compared to devices with a CdS buffer. This finding concurs with the considerably lower capacitance values and also lower charge densities in ZnS-buffered devices, as determined by capacitance voltage measurements.Based on these findings, the main reason for the lower open-circuit voltages of our ZnS devices is that the charge densities are lower than for the CdS/i-ZnO cells.  相似文献   
998.
A wireless multihop network is emerging as one of the most important technologies in the field of ubiquitous networking. However, a number of formidable challenges remain, several of the most crucial been associated with robustness and network security. In this paper, we introduce a comprehensive resilient security framework for wireless ad hoc networks that are using multipath routing. It deploys an integrated multisignatures scheme and uses a self-certified public keying technique to ensure secure route discovery. In addition, it uses the Schnorr signature scheme along with an information dispersal algorithm to ensure secure data transfer. We provide security analysis of the proposed approach and compare it with several existing popular schemes. It can be seen that the proposed approach is more secure than other existing schemes. We also evaluated the proposed approach by means of computer simulation and compared its performance to that of the existing popular schemes. The results are in favor of the proposed technique in terms of efficiency and effectiveness.  相似文献   
999.
Disposable dipstick-type DNA biosensors in the form of lateral flow strips are particularly useful for genotyping in a small laboratory or for field testing due to their simplicity, low cost and portability. Their unique advantage is that they enable visual detection in?minutes without the use of instruments. In addition, the dry-reagent format minimizes the pipetting, incubation and washing steps. In this work, we significantly enhance the multiplexing capabilities of lateral flow strip biosensors without compromising their simplicity. Multiplex genotyping is carried out by polymerase chain reaction (PCR) followed by a single primer extension reaction for all target alleles, in which a primer is extended and biotin is incorporated only if it is perfectly complementary to the target. Multiallele detection is achieved by multiple test spots on the membrane of the sensor, each comprising a suspension of polystyrene microspheres functionalized with capture probes. The products of the primer extension reaction hybridize, through specific sequence tags, to the capture probes and are visualized by using antibiotin-conjugated gold nanoparticles. This design enables accommodation of multiple spots in a small area because the microspheres are trapped in the fibres of the membrane and remain fixed in site without any diffusion. Furthermore, the detectability is improved because the hybrids are exposed on the surface of the trapped microspheres rather than inside the pores of the membrane. We demonstrate the specificity and performance of the biosensor for multiallele genotyping.  相似文献   
1000.
In this paper, we show how linear, but not necessarily shift-invariant, filters can be used to propagate sparse labels throughout an image. We propose a new propagation method based on the domain transform filter, a linear, shift-varying filter whose kernel width varies based on local edge information. We contrast this against the more well-known energy minimization approach and show that it can produce significantly better results when the input labels contain errors. Finally, we show how minimization-based methods are better suited for purely user-guided applications.  相似文献   
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