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991.
In 1900, the world population was less than 1.7 billion people; the United Nations projects that in 2000 it will be 6.2, and in 2020, 7.9 billion. The proportion of the elderly (65 years and over), will increase from 5.1% (1950) to 6.8% by the year 2000 and to 8.8% by 2020, when out of an elderly population of 796 million people, 124 million are projected to be 80 years and over. Due to an increasing gender inequality in life expectation, the majority of the elderly will be women. An aged population is a basically new feature in the history of humanity, the implications of which are-as yet-incompletely understood. It is clear, however, that the last years of life are accompanied by an increase in disability and sickness, with very high demands for health and social services. Hence, the soaring elderly population will raise major social, economic and ethical issues worldwide and may strain to the limit the ability of health, social and economic infrastructures of many countries. It may also result in an increasingly large proportion of humanity (the elderly in general and elderly women, in particular) living in absolute poverty. The demographic, health, socioeconomic and ethical dimensions of the problem are discussed with particular emphasis on the situation of elderly women and a plea is made for greatly increased medical and socioeconomic research. 相似文献
992.
It is suggested that the thermal conductivity of very fine fibres can be evaluated indirectly with the aid of composite theory using the experimental data for the heat transport properties of an appropriate composite which contains the fibres. The feasibility of this approach was investigated by determining the thermal conductivity and diffusivity of fibres of amorphous silicon carbide from 25° C to 1000° C contained within a lithium aluminosilicate glass-ceramic using the laser-flash technique for measurement of the thermal diffusivity of the composite. Due to the amorphous nature of the fibres, values for their thermal conductivity and diffusivity were found to be far less than the corresponding data for crystalline silicon carbide. The positive temperature dependence of the thermal conductivity, coupled with the independent observation of an increase in thermal conductivity with specimen thickness, suggests that radiative heat transfer makes a significant contribution to the total heat transferred. A number of advantages and limitations of the composite method for the evaluation of thermal transport properties of fibres are discussed. 相似文献
993.
RJ Brennan ME Keim TW Sharp SF Wetterhall RJ Williams EL Baker JD Cantwell SR Lillibridge 《Canadian Metallurgical Quarterly》1997,167(11-12):595-598
Planning for the 2000 Sydney Olympic Games may benefit from the experience of the 1996 Atlanta Olympics. Excellent health promotion and prevention activities before and during the Games resulted in fewer medical and public health problems than anticipated. Despite this, there was room for improvement in the level of communication and cooperation between the many service providers to ensure the most appropriate and efficient responses. 相似文献
994.
PURPOSE: The aim of this study was to report the repair of an aneurysm of the internal carotid artery using the endoluminal method. METHODS: A 70-year-old male patient noted a swelling in the right side of his neck 22 years after endarterectomy of the right internal carotid artery. Duplex ultrasound confirmed the clinical diagnosis of aneurysm of the internal carotid artery. Further investigation included contrast-enhanced computed tomographic (CT) scanning and carotid angiography performed via a retrograde femoral approach. The aneurysm contained thrombus and was 3 cm in diameter and in length. It extended superiorly from a point 0.5 cm above the carotid bifurcation to a point estimated to be 2 cm from the base of the skull. Repair of the aneurysm was undertaken using the endoluminal method. A self-expanding endograft 8 mm in diameter and 4 cm in length was introduced through a 12F sheath in the common carotid artery. An on-table completion angiogram of the right-sided extracranial carotid arteries and the intracranial internal carotid artery and branches was obtained. RESULTS: The completion angiogram and postoperative CT scan confirmed exclusion of the aneurysm sac from the circulation. The patient awoke from anesthesia with complete paralysis of the left arm. Recovery of movement commenced 1 hour later. A brain CT scan demonstrated the event to be an embolic stroke. Strength had returned by 7 days. Function of the arm was good 1 month after operation, but coordination for fine movements was lacking. At the 6-month follow-up, good arm function was maintained. A duplex ultrasound scan demonstrated not only continued exclusion of the aneurysm sac but occlusion of the endograft, also. CONCLUSIONS: Endoluminal repair of aneurysms of the internal carotid artery is feasible but carries the risk of major morbidity as a result of peripheral embolization and early occlusion of the endograft. 相似文献
995.
Margaret A. Brennan Emma Derbyshire Brijesh K. Tiwari Charles S. Brennan 《International Journal of Food Science & Technology》2013,48(5):893-902
Consumer appeal for ready‐to‐eat (RTE) products is forecast to grow rapidly over the next 5 years as consumers demand convenient snacks with exciting sensory and textural properties. Extrusion technology has been used extensively in the production of cereal RTE snacks due to its ease of operation and ability to produce a variety of textures and shapes which appeal to consumers. Many of the existing RTE products are relatively high in sugar and salt, thus being regarded as energy dense but nutritionally poor foods. However, there exists a potential to manipulate the nutritional status of extruded RTEs by altering the digestion potentials of starch and protein, and by the incorporation of bioactive components such as dietary fibre. The review article explores some of the recent research in this field and illustrates opportunities by which the global food industry could react to consumers' requirements for healthful RTE snack products in the coming years. 相似文献
996.
997.
This is a case study of the radon diagnostics and mitigation performed by the U.S. Environmental Protection Agency's (EPA's) Office of Research and Development in a New York State school building. Research focused on active subslab depressurization (ASD) in the basement and, to a lesser degree, the potential for radon reduction in the basement and slab-on-grade sections using the heating, ventilating, and air-conditioning (HVAC) system. Based on radon diagnostic measurements in the basement, a five-point ASD system was installed, and recommendations were made to increase the outdoor air supply through the basement unit ventilator. Because of the high radon levels in the basement (1720 bequerels per cubic meter, Bq m?3) and limited subslab pressure field extension, both mitigation approaches were needed to reduce radon to below the current EPA guideline of 148 Bq m?3. The effects of excavating a suction pit under each of the five suction points were also investigated. Pit excavation, together with adjustment of the airflows at the suction points, decreased average radon levels in the basement by an additional 40 percent. In the slab-on-grade section, it was recommended that the school hire a HVAC contractor to evaluate the unit ventilators for increased outdoor air supply. This was recommended both to improve indoor air quality and because diagnostic measurements indicated that an ASD system would require an excessive number of suction points in the slab-on-grade classroom. 相似文献
998.
In this paper, a new image reconstruction scheme is devised for estimating a high-resolution temperature map of the top of the Earth's atmosphere using the Geostationary Operational Environmental Satellite (GOES) imager infrared channels 4 and 5. By simultaneously interpolating the image while estimating temperature, the proposed algorithm achieves a more accurate estimate of the subpixel temperatures than could be obtained by performing these operations independently of one another. The proposed algorithm differs from other Bayesian-based image interpolation schemes in that it estimates brightness temperature as opposed to image intensity and incorporates a detailed optical model of the GOES multichannel imaging system. In order to test the effectiveness of the proposed technique, high-resolution estimates of cloudtop temperatures using GOES channels 4 and 5 are compared to temperature estimates obtained from the Advanced Very High Resolution Radiometer (AVHRR). This test is achieved by examining sets of infrared data taken simultaneously by the GOES and AVHRR systems over the same geographic area. The AVHRR system collects longwave infrared data with a spatial resolution of 1 km, which is higher than the 4-km spatial resolution the GOES system achieves. In some cases, The estimated temperature differences between these systems are as high as 11.5 K. It is shown in this paper that the proposed algorithm improves the consistency between the cloudtop temperatures estimated with the GOES and AVHRR systems by allowing the GOES system to achieve substantially higher spatial resolution. 相似文献
999.
A 25-year-old woman complained of coughing for over 8 weeks. The coughing was not relieved by a bronchodilator (beta 2-adrenoceptor agonist; clenbuterol), and anti-allergic agent (azelastine), or an inhaled corticosteroid. The thromboxane synthetase inhibitor ozagrel completely abolished her cough. In this case, thromboxane A2 may have contributed to the coughing. 相似文献
1000.
D. Algom and W. S. Cain (see record 1992-15186-001) found relative invariance in the pattern of judgments of perceptual and mental mixtures of banana and grass odors. Invariance held both for judgments of total intensity and for those of an individual constituent. For 2 tastes, H. N. J. Schifferstein (see record 84-14495) found a pattern with both similarities to and differences from D. Algom and W. S. Cain's. A key difference lay in finding more symmetry of masking in mental mixtures than in perceptual mixtures. H. N. J. Schifferstein concluded from this alone that any similarity between the perceptual and mental arose from knowledge of "mixture suppression." The authors of this article do not refute the possibility; however, they reject the premise that a statistically reliable difference between the perceptual and the imaginal rules out imagery. The authors review relevant considerations and find no a priori reason to assume that what held for attributes in taste will hold for odors. An approach to resolve the issue is also suggested. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献