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591.
TJ Fuller JP Knochel JP Brennan CD Fetner MG White 《Canadian Metallurgical Quarterly》1976,136(9):979-982
Of 74 patients undergoing long-term hemodialysis who were observed during a 21-month period, seven developed uremic pericarditis. Five of these patients developed intractable pericarditis, unresponsive to intensive dialysis and pericardiocentesis, and were treated with prolonged pericardial drainage (16 to 60 hours) by an indwelling polyethylene catheter and instillation of triamcinolone hexacetonide. Evidence of intractability was based on either the recurrence of cardiac tamponade after pericardiocentesis (two patients) or progression in the size of the pericardial effusion despite four weeks of intensive dialysis (three patients). These five patients recovered and subsequently were observed from 1 to 15 months with no evidence of recurrent pericarditis. This procedure may be an effective alternative to the surgical management of intractable uremic pericarditis, particularly in the patient at high risk for anesthesia and major surgery. 相似文献
592.
A survey of Coccidia on 43 poultry farms in Argentina 总被引:1,自引:0,他引:1
This study aimed to characterize the influence of dietary salt intake on the gene expression of angiotensin II type 1 (AT1) receptor subtypes in different organs. Male Sprague-Dawley rats were fed low salt (0.2 mg/g), normal salt (6 mg/g), or high salt (40 mg/g) diets for 5, 10, and 20 days. mRNA levels for the two AT1 receptor subtypes were determined in adrenal gland, kidney, liver, and lung. In all of the organs examined, with the exception of the adrenal glands, low salt diet led to a transient decrease in the abundance of AT1A receptor mRNA but not of AT1B mRNA, which reached their nadirs between days 5 and 10 of feeding. In the adrenal gland, in which the AT1B receptor is predominant, low salt diet led to a transient increase in the expression of this receptor gene, with a maximum around day 10 of feeding. High salt diet exerted no significant influence on AT1 receptor gene expression in these organs. These findings indicate that the rate of salt intake, in particular, a reduction of salt intake, significantly influences AT1 receptor gene expression in an organ-, time-, and subtype-dependent fashion. It appears that AT1 receptor subtypes are differentially influenced by low salt intake, in that AT1B receptor gene expression increases and AT1A receptor gene expression decreases in this situation. This differential response of AT1 receptor gene expression may be relevant for the organism to be able to adapt to a reduction in oral salt intake. 相似文献
593.
Reviewed research on the relationship between the therapeutic process and potential outcome. Research concerning the impact of a therapist's pregnancy on the psychotherapeutic process was discussed in the context of 5 components that are thought to lead to the outcome of the therapeutic process. These components included the therapeutic contract, therapeutic interventions, the therapeutic bond, the patient's self-relatedness, and therapeutic realizations. Setting clear therapeutic limitations, holding conjoint sessions in transferring clients to new therapists, and considering the role of client diagnosis are important considerations for pregnant therapists in negotiating the therapeutic contract. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
594.
Fuller MI Blalock TN Hossack JA Walker WF 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2007,54(1):79-86
The problem of protecting or isolating extremely sensitive receive circuitry from high-voltage transmit circuitry is commonly addressed through the use of diode bridges, transformers, or high-voltage switches, which prove to be prohibitively expensive, bulky, and power consuming for use in portable, low-cost, battery-powered systems. These approaches also compound the interconnect difficulties associated with two-dimensional (2-D) transducer arrays. In this paper we present a novel transmit protection scheme that allows compact MOSFET shunting devices to be brought on-chip within each receive channel implemented in a standard CMOS integrated circuit process. During transmit, the high voltage transmit pulse is driven onto the common connection of the transducer array and the on-chip MOSFET devices shunt the current to ground. During receive, these devices are turned off, the common connection of the transducer array is shunted to ground, and the received echo can be detected as usual. The transmit protection scheme was experimentally shown to shunt a 16 mA peak current resulting from the equivalent of a 100-V, 25-ns-risetime transmit pulse through a 4 pF transducer element. The scheme was also incorporated into a prototype 1024-channel, low-cost, ultrasound system successfully used to form pulse echo images. 相似文献
595.
Differential reflectometry (DR) is an effective tool to supplement existing explosives detection systems thus making the combined unit more effective than one tool alone. It is an optical technique in which the light beam (UV) emanates from an extended distance onto the substance under investigation, thus rendering it to be a standoff method. DR allows the measurement of the energies that electrons absorb from photons as they are raised into higher, allowed energy states. These electron transitions serve as a "fingerprint" for identifying substances. The device can be made portable; it is fast, safe for the public, does not require human involvement, is cost effective, and most of all, does not require ingestion of a suspicious substance into an instrument. Various embodiments are presented. 相似文献
596.
We report a straightforward, bottom-up, scalable process for preparing mineralized nanofibers. Our procedure is based on flowing feed solution, containing both inorganic cations and polymeric molecules, through a nanoporous membrane into a receiver solution with anions, which leads to the formation of mineralized nanofibers at the exit of the pores. With this strategy, we were able to achieve size control of the nanofiber diameters. We illustrate this approach by producing collagen fibrils with calcium phosphate incorporated inside the fibrils. This structure, which resembles the basic constituent of bones, assembles itself without the addition of noncollagenous proteins or their polymeric substitutes. Rheological experiments demonstrated that the stiffness of gels derived from these fibrils is enhanced by mineralization. Growth experiments of human adipose derived stem cells on these gels showed the compatibility of the fibrils in a tissue-regeneration context. 相似文献
597.
Lorna Unwin Alan Felstead Alison Fuller Dan Bishop Tracey Lee Nick Jewson Peter Butler 《Pedagogy, Culture & Society》2007,15(3):333-348
There is now much awareness of the symbiotic relationship between workplace learning, the organisation of work, level of employee involvement, organisational performance, and the broader economic, regulatory, and social context within which organisations have to operate. This article argues that we have to identify and take serious account of the contextual factors (external and internal) that affect all organisations, as these are central to developing our understanding of the nature of pedagogical practice within any workplace setting. By closely examining the nature and impact of these contextual factors, we can gain greater insight into the phenomenon of why organisations adopt different practices and why they create such different learning environments. The article draws on emerging findings from an ESRC-funded multisector study in the UK and uses illustrations from two contrasting sectors to highlight the impact of context on pedagogical practice. 相似文献
598.
Bioslurry treatment for soils contaminated with very high concentrations of 2,4,6-trinitrophenylmethylnitramine (tetryl) 总被引:1,自引:0,他引:1
Fuller ME Kruczek J Schuster RL Sheehan PL Arienti PM 《Journal of hazardous materials》2003,100(1-3):245-257
Past and current DoD activities have resulted in the contamination of soil, sediment and groundwater with various explosive compounds. This research was undertaken to determine the effectiveness of a soil bioslurry process for remediation of soil with very high concentrations of 2,4,6-trinitrophenylmethylnitramine (tetryl). A 99.9% reduction in tetryl concentrations (from 100,000 to below 100 mg/kg) was achieved in 180 to 200 days. A variety of process modifications (i.e. addition of fertilizer, microbial biomass, purging with nitrogen, etc.) that were performed during the course of the experiment did not increase the tetryl biodegradation rate beyond the rates of degradation without modifications. Subsequent batches of soil added as a 25% (v/v) replacement of the slurry were also degraded. These results indicate the potential for this process to remediate highly contaminated soils at many former and current ammunition manufacturing sites. 相似文献
599.
Urban form, biodiversity potential and ecosystem services 总被引:10,自引:0,他引:10
Jamie Tratalos Richard A. Fuller Philip H. Warren Richard G. Davies Kevin J. Gaston 《Landscape and urban planning》2007,83(4):308-317
Using data from selected areas in five UK cities, we studied the relationships between urban form and the following measures of ecosystem performance: availability and patch characteristics of tree cover, gardens and green space; storm-water run-off; maximum temperature; carbon sequestration. Although most measures of ecosystem performance declined with increasing urban density, there was considerable variability in the relationships. This suggests that at any given density, there is substantial scope for maximising ecological performance. The social status of residents was related to measures of tree cover. Housing type was significantly associated with some types of ecosystem service provision, indicating that the type of development may be important independent of its density. These findings have implications for understanding the distribution of ecosystem services and biodiversity across urban landscapes, and the management of development aimed at meeting UK government housing density targets. 相似文献
600.
Sterling MC Bonner JS Page CA Fuller CB Ernest AN Autenrieth RL 《Environmental science & technology》2003,37(19):4429-4434
This paper investigates the hypothesis that observed polycyclic aromatic hydrocarbon (PAH) concentrations in an aqueous system are equal to the sum of the organic phase and soluble phase molar concentrations. While the organic phase concentrations are proportional to the PAH mole fraction in the oil, the soluble phase molar concentrations are estimated using Raoult's law. A batch laboratory mixing vessel with a scalable mixing energy was loaded initially at various oil layer thicknesses (0.4-3.2 mm) which correspond to oil surface loadings (40-310 mg/cm2). The vessel was agitated at constant mean shear rates (Gm = 5, 20 s(-1)). Total petroleum hydrocarbon (TPH) samples were taken periodically to estimate the entrainment rate as a function of initial oil layer thickness. TPH concentrations were measured in-situ using a laser scattering instrument (LISST-100) and ex-situ using gravimetric analysis. At a steady-state TPH concentration (>72 h), additional samples were analyzed for PAH concentration using GC/MS analysis. TPH concentrations increased over time according to a first-order kinetic model. Generally, the first-order rate constant and steady-state concentration both increased with increased oil loading and with increased Gm. In addition, measured PAH concentrations correlated well (r2 > 0.96) with those predicted by a partitioning model. These results are useful for assessing the effects of mixing and oil loading conditions on crude oil entrainment and PAH partitioning. 相似文献