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71.
The Canadian Armed Forced have been deployed to the republics of the former Yugoslavia since 1992 as part of the United Nations Protection Force and the NATO-led Implementation Force. Most of the combat arms units have been supported by small, self-contained surgical teams for essential surgery. Considerable benefit is gained by cooperating with civilian surgeons. The experience of treating five patients with complicated hydatid disease endemic to the area is examined. Treatment of these patients requires performing major surgical procedures under austere conditions and must be undertaken with care. Careful selection and communication with the surgical nursing team and civilian surgeons is essential. Well selected cases can also pay tremendous dividends in terms of maintaining the skills of personnel who must be prepared for any emergency in addition to providing vital surgical assistance to these patients. 相似文献
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The final stage in the production of a radiotherapy treatment plan must always be an independent check that the linear accelerator settings given on the plan do in fact deliver the required dose distribution. A tool is described that enables rapid checking of diaphragm settings in relation to the patient. 相似文献
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S Brown JN Rumbley AJ Moody JW Thomas RB Gennis PR Rich 《Canadian Metallurgical Quarterly》1994,1183(3):521-532
The carbon monoxide compounds of the fully reduced and mixed valence forms of cytochrome bo from Escherichia coli were laser photolysed under anaerobic conditions at room temperature. The carbon monoxide recombined with characteristic rate constants of 50 s-1 or 35 s-1 in the fully reduced and mixed valence forms, respectively. Rates of CO recombination with the fully reduced enzyme were examined in a variety of mutant forms of cytochrome bo, produced by site-directed mutagenesis. A method was developed to deconvolute cytochromes bo and bd, leading to some reassessment of histidine ligands to the metals. Significant changes in the rate constant of recombination of carbon monoxide occurred in many of these mutants and these results could be rationalised generally in terms of our current working model of the folding structure of subunit I. In the mixed valence form of the enzyme the transient photolysis spectra in the visible region are consistent with a rapid electron redistribution from the binuclear centre to the low-spin haem. This electron transfer is biphasic, with rate constants of around 10(5) and 8000 s-1. The process was also examined in the His-333-Leu mutant, in which a putative histidine ligand to CuB is replaced by leucine, and which results in the loss of the CuB. It appeared that rapid haem-haem electron transfer could still occur. The observation that CuB is apparently not required for rapid haem-haem electron transfer is consistent with the recently proposed model in which the two haems are positioned on opposite sides of transmembrane helix X in subunit I of the oxidase. 相似文献
77.
A. Brown 《Renewable Energy》1993,3(2-3)
The UK Government has supported a programme on Renewable Energy since 1975. In 1988 progress was reviewed and this led to some redirection of the programme with greater emphasis on the commercial development of renewables, as published in Energy Paper 55.The climate in which Renewable Energy operates has been influenced recently by a number of factors including privatisation of the UK electricity supply industry, when the Government introduced the New Fossil Fuel Obligation and publication of the Government's 1990 White Paper on the Environment which noted that the Government is working towards a figure of new renewable energy generating capacity of 1000 MW by 2000.The paper aims to give an overview of the present state of development of the renewable technologies in the UK and to discuss some of the factors - technical and non-technical - which will affect their likely future development. 相似文献
78.
The propagation, reflection, and transmission of a plane wave through a column of two fluids with a material discontinuity is studied by three methods: a mixed finite element formulation with both pressure and velocity at a point taken as independent variables, and a scaled and an un-scaled acoustic pressure formulation in which only the pressure at a point is taken as an independent variable. It is found that when mass densities of two fluids are close to each other, the un-scaled acoustic pressure formulation gives reasonable results. However, when the speeds of sound in two fluids are close to each other but their mass densities are quite different, and for cases where the first fluid has high impedance relative to that of the second fluid, a mixed or scaled pressure formulation is necessary. Without the mixed or scaled pressure formulation, the continuity conditions at the interface between two fluids are not well satisfied for the un-scaled pressure formulation. The consideration of viscosity of the two fluids and using a dispersion correction method in the time integration scheme in the mixed formulation slightly improves results. 相似文献
79.
Early warning systems (EWS) tend to focus on the identification of slow onset disasters such famine and epidemic disease. Since hazardous environmental conditions often precede disastrous outcomes by many months, effective monitoring via satellite and in situ observations can successfully guide mitigation activities. Accurate short term forecasts of NDVI could increase lead times, making early warning earlier. This paper presents a simple empirical model for making 1 to 4 month NDVI projections. These statistical projections are based on parameterized satellite rainfall estimates (RFE) and relative humidity demand (RHD). A quasi-global, 1 month ahead, 1° study demonstrates reasonable accuracies in many semi-arid regions. In Africa, a 0.1° cross-validated skill assessment quantifies the technique's applicability at 1 to 4 month forecast intervals. These results suggest that useful projections can be made over many semi-arid, food insecure regions of Africa, with plausible extensions to drought prone areas of Asia, Australia and South America. 相似文献
80.