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991.
992.
Philip Morrison 《Technology in Society》1986,8(4)
Nationalism and science are two dominant systems of thought and institutions that have evolved together over the past four centuries. An intolerable conflict, however, has arisen between them, and humanity will not survive long if they both continue to flourish. The hundred-fold (or more) reduction in the cost of destruction provided by physicists through the development of nuclear weaponry has brought this conflict to a critical point. Young scientists have a moral imperative to study the relationship between nationalism and science and, although there are no clear answers, to search for a way to resolve the conflict. 相似文献
993.
D Morrison RM Strieter SC Donnelly MD Burdick SL Kunkel W MacNee 《Canadian Metallurgical Quarterly》1998,12(5):1067-1072
Polymorphonuclear neutrophils (PMN) have been implicated in the pathogenesis of emphysema. The chemokines interleukin-8(IL-8), growth-related oncogene (GRO-alpha) and extractable nuclear antigen (ENA)-78 may be involved in the increased numbers of PMN in smokers' airspaces. The levels of these cytokines in bronchoalveolar lavage fluid (BALF) and bronchoalveolar lavage leukocyte conditioned medium (LCM), along with BALF PMN numbers in 12 smokers who abstained for 12 h (chronic smoking) or continued to smoke until I h before study (acute smoking) and seven nonsmokers were compared. Neutrophils in BALF increased in acute (1.96+/-0.53%, 0.99+/-0.32x10(6) cells) compared with chronic smokers (0.59+/-0.25%, 0.61+/-0.24x10(6) cells, p<0.05 nonsmokers) and nonsmokers (0.79+/-0.29%, 0.05+/-0.01x 10(6) cells, p<0.05). There were no differences in IL-8 or GRO-alpha in BALF between smokers and nonsmokers. ENA-78 levels were lower in smokers (p=0.006). There was no difference in IL-8, GRO-alpha or ENA-78 in LCM from unstimulated cells in smokers versus nonsmokers. After stimulation with lipopolysaccharide (LPS) 10 ng mL(-1), IL-8 release in acute smokers (p=0.04) and GRO-alpha release in smokers (p=0.009) were significantly higher than in nonsmokers. Following stimulation with LPS 100 ng.mL(-1), GRO-alpha release was higher in smokers (p=0.03) and increased further in acute smokers (p=0.02 versus nonsmokers, p=0.04 versus chronic smokers) and ENA-78 release increased in smokers (p=0.02 versus non-smokers). In conclusion, influx of polymorphonuclear neutrophils into smokers' airspaces is an acute phenomenon and neutrophil chemokine release from mixed bronchoalveolar lavage leukocytes is influenced by cigarette smoking and endotoxins. 相似文献
994.
TA McDonagh SD Robb DR Murdoch JJ Morton I Ford CE Morrison H Tunstall-Pedoe JJ McMurray HJ Dargie 《Canadian Metallurgical Quarterly》1998,351(9095):9-13
BACKGROUND: In previous studies on the use of natriuretic peptides to detect left-ventricular systolic dysfunction, a higher rate of cardiac disorders in the control groups than in the study groups could have led to bias. We investigated the effectiveness of plasma N-terminal atrial natriuretic peptide (NT-ANP) and brain natriuretic peptide (BNP) concentrations to show left-ventricular systolic dysfunction in a random sample of the general population. METHODS: We randomly selected 2000 participants aged 25-74 years from family physicians' lists in Glasgow, UK. We sent all participants questionnaires. 1653 respondents underwent echocardiography and electrocardiography. We took a left-ventricular ejection fraction of 30% or less to show left-ventricular systolic dysfunction. NT-ANP and BNP were measured in plasma by RIAs. FINDINGS: 1252 participants had analysable electrocardiograms and echocardiograms, completed questionnaires, and available blood samples. Median concentrations of NT-ANP and BNP were significantly higher in participants with left-ventricular systolic dysfunction (2.8 ng/mL [IQR 1.8-4.6] and 24.0 pg/mL [18.0-33.0]) than in those without (1.3 ng/mL [0.9-1.8] and 7.7 pg/mL [3.4-13.0]; each p < 0.001). Among participants with left-ventricular systolic dysfunction, both symptomatic and asymptomatic subgroups had raised NT-ANP and BNP concentrations. A BNP concentration of 17.9 pg/mL or more gave a sensitivity of 77% and specificity of 87% in all participants, and 92% and 72% in participants aged 55 years or older. INTERPRETATION: Measurement of BNP could be a cost-effective method of screening for left-ventricular systolic dysfunction in the general population, especially if its use were targeted to individuals at high risk. 相似文献
995.
The Digital Vision Touch (DViT) system uses smart cameras to determine where a person touches a large display, thereby allowing intuitive human-computer interaction. The cameras process the collected images in such a way as to recognize various object attributes, such as location relative to the display in 3D space. The system can then use this information in feedback to the computer generating the display, enabling touch control of the application. When we touch-enable large displays, multiuser collaboration and the ability to detect pen or finger contact are desirable functions. DViT is a touch-enabling technology with this capability and facilitates human-computer interaction in a natural way. The system we created works with a variety of display sizes - both large and wall-sized formats - and accommodates multiple users simultaneously. 相似文献
996.
Joan Cahill Nick McDonald Rabea Morrison Darragh Lynch 《Cognition, Technology & Work》2016,18(3):479-509
This paper presents a case study pertaining to human factors/human–machine interaction (HMI) research undertaken over a four-year period, as part of a large Framework Seven project funded by the European Commission. Specifically, it reports on research concerning the operational validation of future cockpit concepts supporting all conditions operations. Primarily, it focuses on the innovation in the methodological approach adopted (and the theory underpinning this) and the key results. In so doing, this paper illustrates the requirement for HMI research to go beyond issues of task and user interface design, so as to properly address issues of operability. It is argued that the typical remit of operational assessment (i.e. the assessment of task workflows, workload and operator situation awareness) must be supplemented by a broader analysis of ‘operational’ issues related to the design of operational processes/procedures, teamwork, system information flow, process benefits and implementation barriers. This is enabled by the adoption of a stakeholder/participatory approach to evaluation and the application of both formal and informal HMI design/evaluation methods. 相似文献
997.
Emily Kunen Jason M. Keith Peter W. Grant Julia A. King Faith A. Morrison 《应用聚合物科学杂志》2007,106(1):433-438
There is an emerging market for conductive resins for use in fuel cell bipolar plates. This research focuses on developing a finite element model of a capillary rheometer. Comsol Multiphysics 3.2b was used to model the flow of a remeltable thermoplastic matrix material, Vectra A950RX Liquid Crystal Polymer, with varying amounts of either a carbon black or synthetic graphite filler, to obtain the velocity profile and pressure drop of these composites within the capillary. Previous experimental results have shown that the molten composites obey a shear‐thinning power law behavior. When comparing the model predicted pressure drops from the model with the experimental data, very good agreement was obtained. This signifies that the rheological behavior of the composites can be described by a power law relationship, using parameters specific to each composite. When comparing the modeled velocity profile with the theoretical profile, it was found for all composite formulations that the velocity becomes fully developed within a length of 0.05 times the diameter of the tube, independent of the power law parameters n and m. This work is a necessary first step in developing 2D or 3D mold filling simulations for fuel cell bipolar plate applications. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
998.
999.
Automatic alignment of optical interferometers 总被引:1,自引:0,他引:1
1000.
The imaging characteristics for X-ray wavelengths in the "water window" under incoherent imaging conditions (large detector aperture) are examined for the King's College London scanning transmission X-ray microscope with zone-plate objective installed at the Daresbury (UK) synchrotron. The principal consideration was to express image theory, incorporating wave aberrations and apodised zone plates, and to apply the theory to experimental data. Comparisons are made, showing reasonable agreement, for a range of defocus values and two wavelengths. Due to problems in fabrication it was necessary to determine the effective, or operational, zone-plate parameters (radius of outermost active zone rN, width of outermost active zone drN); this was accomplished by through-focus series. Calculated point spread functions were used to deblurr images, in through-focus series of two-dimensional scanned X-ray images of specimen holes and test grating patterns. Significant contrast enhancement is achieved after deconvolution with a best point-to-point resolution of about 35 nm. 相似文献