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991.
992.
This paper presents the main findings of a 1994 survey of UK industry practices in the evaluation and realisation of IS/IT benefits (‘benefits management‘). The survey addresses the issues which affect the ability of organizations to realise the full benefits of IS/IT investments, i.e. not only the pre-investment appraisal and post-investment evaluation processes, but also how organizations do or do not ensure that benefits claimed are actively managed through to realisation. To do this a new benefits management process model was used to structure a questionnaire to elicit details of how effective organizations are in addressing benefits management throughout the investment lifecycle. Sixty organizations responded to the survey, thus providing a wealth of data for analysis. This paper presents some of the key results of that analysis. From the survey, it is clear that many organizations believe that current methods are far from satisfactory in ensuring that the benefits are properly identified and realised. Very few have a comprehensive process for managing the delivery of benefits from IS/IT. This paper offers new insight into the reasons for the current unsatisfactory situation and points the way to how the situation could be significantly improved. 相似文献
993.
Controlled overproduction of proteins by lactic acid bacteria 总被引:2,自引:0,他引:2
OP Kuipers PG de Ruyter M Kleerebezem WM de Vos 《Canadian Metallurgical Quarterly》1997,15(4):135-140
Lactic acid bacteria are widely used in industrial food fermentations, contributing to flavour, texture and preservation of the fermented products. Here we describe recent advances in the development of controlled gene expression systems, which allow the regulated overproduction of any desirable protein by lactic acid bacteria. Some systems benefit from the fact that the expression vectors, marker genes and inducing factors can be used directly in food applications since they are all derived from food-grade lactic acid bacteria. These systems have also been employed for the development of autolytic bacteria, suitable for various industrial applications. 相似文献
994.
Negative Poisson's ratios in angle-ply laminates 总被引:1,自引:0,他引:1
Abstracts are not published in this journal
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
995.
RJ Brockhurst RC Ward P Lou D Ormerod D Albert 《Canadian Metallurgical Quarterly》1993,115(4):524-529
The local antibody response to the outer membrane protein, P6, of nontypable H. influenzae was measured in middle ear fluids of 30 children during 46 episodes of otitis media, and in nasopharyngeal secretions from 7 children evaluated on 18 occasions. Immunoglobulin G antibody to P6 was detected in 92% of middle ear fluid compared to 70% for IgM, 78% for IgA, and 45% for secretory IgA. Antibody levels ranged from a high of 249 ng/ml for IgG to a low of 11 ng/ml for IgM. Concentrations of P6 specific IgG in the middle ear fluid was directly related to the concentration in the serum, r = 0.89, p < 0.001, and inversely related to the number of bacteria present, r = -0.62, p < 0.05. In contrast, IgA and secretory IgA antibodies to P6 were common (96% and 95%, respectively) and in relatively high concentrations (33 ng/ml and 29 ng/ml, respectively) in nasopharyngeal secretions. There was no relationship between nasopharyngeal and serum levels of antibodies. These data suggest that antibody to P6 nontypable H. influenzae is common, diffuses into the middle ear spaces passively from the serum during otitis media, and is manufactured locally in the nasopharynx in response to colonization. 相似文献
996.
AA Kruize RJ Hené A van der Heide C Bodeutsch PC de Wilde OP van Bijsterveld J de Jong TE Feltkamp L Kater JW Bijlsma 《Canadian Metallurgical Quarterly》1996,39(2):297-303
OBJECTIVE: To assess long-term outcome in patients with isolated keratoconjunctivitis sicca (KCS), primary Sj?gren's syndrome (SS), and secondary SS. METHODS: In 112 patients referred because of dry eyes, an ophthalmologic diagnosis of KCS was made based on results of the Schirmer I test, the tear fluid lysozyme concentration, and rose bengal staining. Subsequent assessments, including sublabial salivary gland biopsy, were performed. Followup assessments were performed 10-12 years after initial diagnosis. RESULTS: Six patients were excluded because no biopsy specimen was available. Seventy-three percent of the remaining 106 patients were female, with a mean age of 53.5 years and a mean symptom duration of 3.9 years. Application of the 1987 classification criteria of Daniels and Talal revealed a diagnosis of isolated KCS in 56 patients, primary SS in 31, and secondary SS in 19. At baseline, 2 of 56 patients with isolated KCS and 8 of 31 with primary SS exhibited mild features of organ-specific autoimmune disease. At followup, 2 of 38 patients with isolated KCS and 4 of 21 with primary SS had developed new features related to autoimmune disease, not necessitating treatment with corticosteroids; none of the patients developed major glandular complications. Three of 30 patients with primary SS died of malignant lymphoma. In 1 of these patients, the possibility could not be excluded that sicca symptoms and infiltrates seen on sublabial salivary gland biopsy had occurred concomitantly with early stages of lymphoma. Malignant lymphoma did not develop in any of the patients with isolated KCS or secondary SS. CONCLUSION: Primary Sj?gren's syndrome is characterized by a stable and rather mild course of glandular and extraglandular manifestations, in marked contrast to the increased risk of development of malignant lymphoma in these patients. Since patients with isolated KCS do not have an increased risk for development of malignant lymphoma, a presumptive diagnosis of primary SS should be confirmed in patients with sicca syndrome. 相似文献
997.
HE Shannon FP Bymaster DO Calligaro B Greenwood CH Mitch BD Sawyer JS Ward DT Wong PH Olesen MJ Sheardown 《Canadian Metallurgical Quarterly》1994,269(1):271-281
Xanomeline [3(3-hexyloxy-1,2,5-thiadiazol-4-yl)-1,2,5,6-tetrahydro-1- methylpyridine] has been evaluated as a muscarinic receptor agonist. In vitro, xanomeline had high affinity for muscarinic receptors in brain homogenates, but had substantially less or no affinity for a number of other neurotransmitter receptors and uptake sites. In cells stably expressing genetic m1 receptors, xanomeline increased phospholipid hydrolysis in CHO, BHK and A9 L cells to 100, 72 and 55% of the nonselective agonist carbachol. In isolated tissues, xanomeline had high affinity for M1 receptors in the rabbit vas deferens (IC50 = 0.006 nM), low affinity for M2 receptors in guinea pig atria (EC50 = 3 microM), was a weak partial agonist in guinea pig ileum and was neither an agonist nor antagonist in guinea pig bladder. In vivo, xanomeline increased striatal levels of dopamine metabolites, presumably by acting at M1 heteroreceptors on dopamine neurons to increase dopamine release. In contrast, xanomeline had only a relatively small effect on acetylcholine levels in brain, indicating that it is devoid of actions at muscarinic autoreceptors. In the gastrointestinal tract, xanomeline inhibited small intestinal and colonic motility, but increased small intestinal transmural potential difference. In contrast to the nonselective muscarinic agonist oxotremorine, xanomeline did not produce salivation, tremor nor hypothermia; it did, however, increase heart rate. The present data are consistent with the interpretation that xanomeline is a novel muscarinic receptor agonist with functional selectivity for M1 muscarinic receptors both in vitro and in vivo. 相似文献
998.
T. Y. Liu P. J. Ward H. V. Atkinson D. H. Kirkwood 《Metallurgical and Materials Transactions A》2003,34(2):409-417
Semisolid metal alloys, used in thixoforming, are thixotropic. The slurry viscosity is shear-rate- and time dependent provided
the microstructure in the semisolid state is nondendritic and consists of solid spheroids surrounded by liquid. Thixoforming
takes less than 1 second, during which time the structure of the material breaks down. This breakdown can be studied by viscometry,
using rapid data-collection rates, by imposing rapid increases in shear rate on the slurry. An initial rapid (<1 second) structural
breakdown during a shear-rate jump is followed by a more gradual decrease in viscosity, lasting several minutes. The slurry
breaks down more rapidly with a higher final shear rate, but the first breakdown time is independent of the initial shear
rate. The reverse is found with the shear-rate drops: recovery times increase with increasing final shear rate. Again, this
time is independent of the starting shear rate. The shear stress and viscosity during initial breakdown and initial recovery
can be described by single exponential equations. Build-up processes were examined by performing jumps after allowing the
slurry to rest at a zero shear rate for different times. The increase in peak stress with rest time reflects the evolving
degree of particle agglomeration. Microstructural examination confirms this phenomenon. 相似文献
999.
S Day H Ward A Ghani G Bell U Goan M Parker E Claydon C Ison G Kinghorn J Weber 《Canadian Metallurgical Quarterly》1998,9(11):666-671
We aimed to describe and compare sexual links among people with gonorrhoea, by studying patients in 2 UK departments of genitourinary medicine. Interviews were completed for 510 and 235 cases in London and Sheffield respectively. There was a greater proportion of cases in men, homosexual men, non-white and non-British people and fewer female sex workers in London. Total networks of 1738 people in London and 570 people in Sheffield were described. Large linked heterosexual networks identified in Sheffield were associated with local contact, including men with higher numbers of sexual partners. Condom use for vaginal sex was reported for 11% of heterosexual partnerships in Sheffield, and 27% in London, with little difference between regular and casual partners. It was more difficult to define networks in London due to a high proportion of relatively anonymous contacts. These difficulties suggest that research and interventions may profitably focus upon venues for meeting partners as well as partner notification. 相似文献
1000.
Here we describe the development of a process, and the resulting mechanical properties, for hot‐compacted sheets of woven poly(ethylene terephthalate) (PET) multifilaments. Investigation of the various processing parameters showed that a key aspect was the time spent at the compaction temperature, termed the dwell time. Molecular weight measurements, using intrinsic viscosity, showed that hydrolytic degradation occurred rapidly at the temperatures required for successful compaction, leading to embrittlement of the resulting materials with increasing dwell time. A dwell time of 2 min was found to be optimum because this gave the required percentage of melted material to bind the structure together, while giving only a small decrease in molecular weight. A combination of techniques, including mechanical tests, differential scanning calorimetry, and scanning electron microscopy, was used to examine the mechanical properties and morphology of the optimum compacted sheets. These tests reinforced the view from previous studies on hot‐compacted polypropylene, of hot‐compacted sheets as self‐reinforced composites, whose behavior is a combination of the properties of the two components, that is, the original oriented multifilaments and the melted and recrystallized matrix. Other key findings from the research included a confirmation of the importance of obtaining high ductility in the melted and recrystallized phases, promoted by using a high molecular weight or by suppressing crystallinity during processing, and the proportionately high‐impact performance of hot‐compacted sheets, compared with that of other materials. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2223–2233, 2004 相似文献