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991.
Studying the interaction of components is basic for a railroad project, which is also very important for creating maintenance procedures based on predictions from a model that assumes adequate performance. To determine these interactions, which can have a great number of combinations, the use of a computational model is of vital importance, in this case, the program FERROVIA 1.0 (RAILROAD 1.0) was used. A critical study developed the program FERROVIA 1.0, and its variables were characterized based on values observed in the literature. After initial characterization was carried out, a comparative study was performed on the sensitivity between these variables and the indications of significant behavior for a railway deformed by the known load of a wheel. A statistical program was used to correlate the elements. The intention was to launch the program FERROVIA 1.0 and later use it for 2,187 combinations. The data used in these correlations corresponded to the normal values for the elements used in railroad engineering practice. Our main goal is to understand the behavior of the track vertical deflection according to the variation of the scaling of the various elements of the railway,  相似文献   
992.
The integration of landscape connectivity criteria into spatial planning through ecological networks formed by coherent open space systems has received increasing attention in Europe in the last few decades. In Spain, such integration began recently, in parallel with the development of a supralocal comprehensive spatial planning policy, which was practically non-existent a decade ago. An assessment of such integration is reported here, specifically on ecological networks inclusion within the spatially explicit zoning regulations of 11 regional and 66 subregional plans which had been approved in Spain until the end of 2012. At the same time, a survey was conducted among 22 Spanish and 14 European practitioners in order to detect possible deficiencies and opportunities to optimise this integration in Spain through a comparison with other European countries. An increasing integration of ecological networks into supralocal plans was observed, especially in subregional plans approved in the last five years, coinciding with a period of greater development in supralocal spatial planning policy, the end of the Spanish speculative housing bubble and new national legislation which encourages the promotion of ecological networks. However, the integration process is very uneven because homogeneous guidelines are not applied in the different regions. Spanish practitioners discerned wide room for improvement. The integration of ecological networks into multiscale spatial planning should be optimised in Spain, including improvements in local planning, strategic environmental assessment and training of planners in this topic.  相似文献   
993.
Samples of 2.25Cr–1Mo steel in the form of tubes have been examined in the new condition and after extended service in a power station. The differences in microstructure in terms of precipitates have been characterized using a TEM; the various precipitates present have been identified individually by using extraction replicas and energy dispersive spectroscopy analysis. The area fraction of each type of precipitate was calculated. The results have shown that the quantity of M7C3 precipitated within grains as well as on grain boundaries decreased markedly with the time in service while the quantity of M6C increased in both regions. It was observed that precipitates of Mo2C and (CrMo)2CN, detected after aging respectively on the samples with the shorter and the longer aging times, were present only within grains. The procedure used was not accurate for identification and quantification of small VC and (VNb)C precipitates. The results of the relative quantity of M7C3 and M6C, as a function of time in service, particularly on grain boundaries, showed a well defined interdependence. These results can be used as a complementary analysis for creep damage and remaining life estimation for this class of steel operating at high temperature under steady state conditions.  相似文献   
994.
A low inner volume (ca. 64 ml) probe was built up in an injector-commutator in order to behave as a photometric leaping detector in flow analysis. It comprises a bicolour light-emitting diode (BLED), as a source of pulsed radiation in the red and green visible region, and two phototransistors as transducers. Sample injection, detector relocation, analytical signal recording, data treatment and definition of the spectral working range were computer-controlled. The feasibility of the system was initially demonstrated in the flow-injection speciation of iron, and the overall standard deviation of results was estimated as +/- 1.6 and +/- 1.4% for 1.6-4.0 mg l(-1) Fe(II) or total iron after eightfold processing of synthetic samples. The system was further applied to drug analysis: the mean deviations of results for typical samples were estimated as +/- 5.2 and +/- 3.3%, and the relative standard deviation as +/- 1.6 and +/- 1.3% for Fe(II) and total iron, respectively. Results were compared with those obtained by a conventional spectrophotometric procedure and no statistic differences at the 95% confidence level were found. In relation to an earlier system with multi-site detection, the proposed system is more stable, presenting low drift with a relative standard deviation of 0.026% and 0.039% for measurements (n=120 during 4 h of observation) with green and red emission. It is also faster with a sampling rate of 133 h(-1) and carryover problems are not found. The possibility of compensating the Schlieren noise by dual-wavelength spectrophotometry is discussed.  相似文献   
995.
Over the last decade, increased transportation of refrigerated raw milk from farms to factories has raised concerns over Bacillus cereus contamination in the Brazilian dairy industry. Twelve isolates from pasteurized milk and 30 isolates from the post-pasteurization equipment surfaces of a dairy processing unit were characterized as B. cereus. Seven ribotypes were identified, demonstrating the genetic variability of this microorganism. Most of the isolates belonged to the same ribogroup (RIBO1222-73-S4), and they were found on four surfaces and also in the milk, indicating the role of the equipment surfaces as reservoirs for milk recontamination.  相似文献   
996.
Microporous AM-11 crystalline niobium silicates were studied as solid acid catalysts for the dehydration of xylose in a water-toluene solvent mixture at 140–180 °C. After 6 h at 160 °C, xylose conversions of up to 90% and furfural yields of up to 50% were achieved, and the catalysts could be reused without loss of activity or selectivity. The calcined AM-11 catalysts gave higher furfural yields than HY zeolite and mordenite, under identical reaction conditions. Ordered mesoporous MCM-41-type niobium silicates with Si/Nb molar ratios of either 25 or 50 were also found to be recyclable catalysts for xylose dehydration, and gave furfural yields consistently in the range of 34–39% (after 6 h reaction at 160 °C).  相似文献   
997.
PURPOSE: To evaluate the influence of surface treatment of silicone-hydrogel CL on lens hydrophobicity, protein adsorption and microbial colonisation by studying several silicone hydrogel contact lenses (CL) with and without surface treatment. The lenses used in this study were Balafilcon A, Lotrafilcon A, Lotrafilcon B and Galyfilcon A. A conventional hydrogel CL (Etafilcon A) was also tested. METHODS: Hydrophobicity was determined through contact angle measurement using the advancing type technique on air. The type and quantity of proteins adsorbed were assessed through SDS-PAGE and fluorescence spectroscopy, respectively. Microbial colonisation was studied by removing the microbes from the lenses through sonication, and counting the colony-forming units on agar plates. RESULTS: Regarding hydrophobicity, both surface and non-surface-treated silicone hydrogel CL were found to be hydrophobic, and the conventional hydrogel CL was found to be hydrophilic. Concerning protein adsorption, different protein profiles were observed on the several lenses tested. Nevertheless, the presence of proteins with the same molecular weight as lysozyme and lactoferrin was common to all lenses, which is probably related to their abundance in tears. In terms of total protein adsorption, silicone hydrogel CL did not exhibit any differences between themselves. However, the conventional hydrogel Etafilcon A adsorbed a larger amount of proteins. Regarding microbial colonisation, Balafilcon A exhibited the greatest amount of colonising microbes, which can be due to its superior hydrophobicity and higher electron acceptor capacity. CONCLUSION: This study suggests that silicone hydrogel lenses adsorb a lower amount of proteins than the conventional hydrogel lenses and that this phenomenon is independent of the presence of surface treatment. Concerning microbial colonisation, the surface treated Balafilcon A, exhibited a greater propensity, a fact that may compromise the lens wearer's ocular health.  相似文献   
998.
Maps of polarization and anisotropy can be helpful for flow analysis systems (FIA, CFA, etc.) with reactions dependent on the intermolecular alignment as well as for dispersion control. Maps can be acquired manually, but when a scan over a sample area is required, the acquisition becomes tiresome and has low precision. The paper describes an automatic flexible system for high-precision sample positioning with closed loop self control, remote data acquisition and storage controlled by a BASIC program. The system was developed to acquire maps up to 850 mm(2) of the sample (liquid flows, solids, interfaces, etc.), with up to 100 mum(2) precision. To evaluate the equipment, performance is presented as the scan of a thin liquid film of monoethylene glycol (MEG) flowing on borosilicate. Tests were performed with and without surfactantes at submicellar concentrations: two concentrations of sodium dodecyl sulphate (SDS) and one of polyethylene oxide (PEO). For pure MEG, the intermolecular alignment initially increased, then decreased. When SDS was added, both polarization and anisotropy only increased progressively with the flow. This might be explained by the surfactant decrease of interfacial interaction. When PEO was added, both polarization and anisotropy decreased pronouncedly over the entire map, which might be due to macromolecular aggregates within the bulk generating misaligned molecular domains. The system presented as sample positioning repeatability of 0.1% and a high polarization reproducibility (error margin < 6 in 1000).  相似文献   
999.
This software package was written to semi-automate the routine calculation of antibody titres from ELISA data without standards, by fitting the data to a generalised four parameter logistic curve. Data recording from a plate reader by direct serial interface to a diskfile is also facilitated.  相似文献   
1000.
Acidic compounds in cracked components of gasoline, isolated by extraction with aqueous solutions of sodium bicarbonate and sodium hydroxide, were identified as phenol and its mono- di - tri- and tetramethyl- derivatives. Aromatic sulfur compounds seDarated as the hexanc and benzene fractions by chromatography on an alumina column were identified as thiophenc, its mono- di - and trimethyl- derivatives, ethylihiophenc, benzolhiophene and methylbenzoihiophene. The identification of the phenolic compounds was achieved by IR, hydrogen-1 and carbon-13 NMR spectroscopy and GC - MS. Additionally, for complete identification of sulfur compounds a GC equipped with a selective sulfur detector was used. ISD Induction System Deposit (ISD) tests showed a decreased deposit-forming tendency for phenol compounds and no significant deposit formation for aromatic sulfur compounds or other fractions isolated.  相似文献   
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