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81.
Recently, AAR was identified in submerged piles of some bridges in tidal waters. Microstructural examination detected chloroaluminate salts in some cracks. To clarify whether seawater had influenced the deterioration an experimental program was planned to examine the effects of sodium chloride on AAR under various curing conditions.Concrete prisms containing either of highly-reactive, slowly-reactive or nonreactive aggregate, and either low or high alkali contents, were stored in saltwater (representing seawater) or at 100% RH, at temperatures of 38, 60 and 80 °C, for expansion measurement over 600 days, after which the temperature for those stored in saltwater was lowered to 23 °C, to check its effect on further expansion, which could be attributed to precipitation of ettringite and/or Ca-chloroaluminate.The results indicate that the type of aggregate and concrete alkali content had the greatest effect on AAR expansion. Exposure to saltwater did not have any significant effect on the AAR expansion. 相似文献
82.
Bruna Panizzutti Chiara C. Bortolasci Briana Spolding Srisaiyini Kidnapillai Timothy Connor Mark F. Richardson Trang T. T. Truong Zoe S. J. Liu Gerwyn Morris Laura Gray Jee Hyun Kim Olivia M. Dean Michael Berk Ken Walder 《International journal of molecular sciences》2021,22(13)
Recent reports suggest a link between positive regulation of the Hippo pathway with bipolar disorder (BD), and the Hippo pathway is known to interact with multiple other signaling pathways previously associated with BD and other psychiatric disorders. In this study, neuronal-like NT2 cells were treated with amisulpride (10 µM), aripiprazole (0.1 µM), clozapine (10 µM), lamotrigine (50 µM), lithium (2.5 mM), quetiapine (50 µM), risperidone (0.1 µM), valproate (0.5 mM), or vehicle control for 24 h. Genome-wide mRNA expression was quantified and analyzed using gene set enrichment analysis (GSEA), with genes belonging to Hippo, Wnt, Notch, TGF- β, and Hedgehog retrieved from the KEGG database. Five of the eight drugs downregulated the genes of the Hippo pathway and modulated several genes involved in the interacting pathways. We speculate that the regulation of these genes, especially by aripiprazole, clozapine, and quetiapine, results in a reduction of MAPK and NFκB pro-inflammatory signaling through modulation of Hippo, Wnt, and TGF-β pathways. We also employed connectivity map analysis to identify compounds that act on these pathways in a similar manner to the known psychiatric drugs. Thirty-six compounds were identified. The presence of antidepressants and antipsychotics validates our approach and reveals possible new targets for drug repurposing. 相似文献
83.
George W. Mushrush Robert E. Pellenbarg Robert N. Hazlett Robert E. Morris Dennis R. Hardy 《Petroleum Science and Technology》2013,31(9):1137-1149
ABSTRACT The reactions that lead to fuel instability are the subject of conflicting reports in the literature. Confusion results from the difficulty in relating differences in fuel composition, temperature, surface effects and dissolved oxygen content that comprise the multitude of reported studies. Model studies offer a means by which the mechanism of an individual reaction can be related to a simple system and then extended to the more complex fuel media. This paper reports a model oxidation study of a cyclic sulfide, tetrahydrothiophene, with an active oxygen species, t-butyl hydroperoxide under mild reaction conditions, 120°C, in a tetradecane model fuel. The major oxidation product was tetrahydrothiophene sulfoxide from the sulfide and t-butanol from the hydroperoxide. The complete suite of products is reported. 相似文献
84.
The microbial integrity of many types of flexible food packages depends on a zero defect level in the fused seam seal. Human inspection for defects in these seals is marginal at best, and secondary incubation protocols are often used to spot packages with compromised integrity before releasing product for sale. A new type of inspection method has been developed and is being evaluated for robustness. The purpose of the study was to evaluate a new raster scanning geometry to simulate continuous motion, online ultrasonic inspection of the seal region in flexible food package seals. A principal engineering tradeoff of scanning inspection systems is between increased line speed that results from decreased spatial sampling (less acquired data to process) and decreased image quality. The previously developed pulse-echo Backscattered Amplitude Integral (BAI) mode imaging technique is used to form ultrasound images using the new scanning geometry. At an ultrasonic frequency of 22.9 MHz, 38- and 50-microm-diameter air-filled channel defects in all-plastic transparent trilaminate are evaluated. The contrast-to-noise ratio (CNR) of the processed BAI-mode image is used to quantify image quality as a function of spatial sampling. Results show seal defects (38- and 50-microm diameter) are still detectable for undersampled conditions, although image quality degrades as spatial sampling decreases. Further, it is concluded that the raster scanning geometry is feasible for online inspection. 相似文献
85.
Bishop GA Morris JA Stedman DH Cohen LH Countess RJ Countess SJ Maly P Scherer S 《Environmental science & technology》2001,35(8):1574-1578
On-road measurements of carbon monoxide, hydrocarbons, and nitric oxide from 5772 heavy-duty diesel trucks at five locations in the United States and Europe show slightly increasing emissions with increasing altitude. The result for nitric oxide showed a statistically significant increase of 4.1 +/- 1 gNO/kg of fuel consumed/km increase in altitude. The increases for CO and HC were also statistically significant. 相似文献
86.
Xin Sun Jiacheng Bao Kai Li Morris D. Argyle Gang Tan Hertanto Adidharma Kaihang Zhang Maohong Fan Ping Ning 《Advanced functional materials》2021,31(7):2006287
Plasma technology is an eco-friendly way to modify or fabricate carbon-based materials (CBMs) due to plasmas’ distinctive abilities in tuning the surface physicochemical properties by implanting functional groups or incorporating heteroatoms into the surface without changing the bulk structure. However, the mechanisms of functional groups formation on the carbon surface are still not clearly explained because of the variety of different discharge conditions and the complexity of plasma chemistry. Consequently, this paper contains a comprehensive review of plasma-treated carbon-based materials and their applications in environmental, materials, and energy fields. Plasma-treated CBMs used in these fields have been significantly enhanced in recent years because these related materials possess unique features after plasma treatment, such as higher adsorption capacity, enhanced wettability, improved electrocatalytic activity, etc. Meanwhile, this paper also summarizes possible reaction routes for the generation of functional groups on CBMs. The outlook for future research is summarized, with suggestions that plasma technology research and development shall attempt to achieve precise control of plasmas to synthesize or to modify CBMs at the atomic level. 相似文献
87.
Batten Sonja V.; Drapalski Amy L.; Decker Melissa L.; DeViva Jason C.; Morris Lorie J.; Mann Mark A.; Dixon Lisa B. 《Canadian Metallurgical Quarterly》2009,6(3):184
[Correction Notice: An erratum for this article was reported in Vol 7(3) of Psychological Services (see record 2010-17074-004). The copyright for the article was listed incorrectly. This article is in the Public Domain. The online version has been corrected.] The present study examined interest in family involvement in treatment and preferences concerning the focus of family oriented treatment for veterans (N = 114) participating in an outpatient Veterans Affairs outpatient posttraumatic stress disorder (PTSD) program. Most veterans viewed PTSD as a source of family stress (86%) and expressed interest in greater family involvement in their treatment (79%). These results suggest the need to consider increasing family participation in the clinical care of individuals with PTSD and to develop specialized family educational and support services for this population. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
X. Ye T. Ganley J.F. Morris N. Tonmukayakul M.A. Parker 《Journal of Petroleum Science and Engineering》2009,65(3-4):193-207
A uniaxial compression apparatus designed to investigate the dynamics of proppant particle packing is described. This dynamic compression device (DCD) uses a small charge of particles, approximately 3.5–7 cm3 depending upon the configuration of an experiment. The DCD allows simultaneous measurement of boundary stresses on the packing and permeability of the packing to fluid flow. Visualization of the packing at compressive stress levels up to σA = 7100 psi (49 MPa) is also demonstrated. The stresses measured are the normal stress at both walls on the axis of compression, with their difference providing a measure of the shear (or friction) force from the walls, and the transverse normal stress on one orthogonal axis, σT. Permeability may be determined by either a fixed pressure drop or fixed flow rate experiment, with results presented from the fixed pressure drop approach by imposing a small gravity head of the flowing liquid; liquid flow is gravimetrically measured.The behaviors of packings of hard particles, both uncoated and when coated with a very viscous and tacky polyamide resin, are reported. The packing materials include a ceramic material used as a proppant in hydraulic fracturing of petroleum wells, and glass beads. The proppant and glass beads have mean diameters of approximately 700 μm and 500 μm, respectively, with the proppant less spherical and more polydisperse than the glass beads. The proppant particles undergo only limited breakage up to the maximum stress imposed here. The glass beads undergo significant breakage. Protocols for the compression can be varied. The reported results use a single loading and unloading at the same speed in each segment (increasing and decreasing stress), as well as a cyclic loading of differing numbers of cycles. The rate of loading is specified and can be varied from 0.56 μm/s–1.7 mm/s, with results here focusing on the range of 1–30 μm/s. Measured stress and permeability are shown as a function of axial load and loading rate, as well as the behavior in cyclic loading. The results are shown to be highly reproducible, establishing the ability to determine the properties of a proppant pack in a small charge device with imposed deformation. The influence of the resin coating on the properties is reported.Direct visualization is one of the key features of the DCD. Local motions and overall rearrangements of particles can be monitored by digital camera. These have been presented using particle image velocimetry (PIV). 相似文献
89.
Charlton Rebecca A.; Barrick Thomas R.; Markus Hugh S.; Morris Robin G. 《Canadian Metallurgical Quarterly》2009,24(2):338
The study investigated age-related differences in theory of mind and explored the relationship between this ability, other cognitive abilities, and structural brain measures. A cohort of 106 adults (ages 50–90 years) was recruited. Participants completed tests of theory of mind, verbal and performance intelligence, executive function, and information processing speed and underwent structural magnetic resonance imaging (measurement of whole brain volume, volume of white matter hyperintensities, and diffusion tensor imaging of white matter integrity). Theory of mind ability declined with increasing age, and the relationship between theory of mind and age was fully mediated by performance intelligence, executive function, and information processing speed and was partially mediated by verbal intelligence. Theory of mind performance correlated significantly with diffusion tensor imaging measures of white matter integrity but not with volume of white matter hyperintensities or whole-brain volume. Theory of mind age-related decline may not be independent of other cognitive functions; it may also be particularly susceptible to changes in white matter integrity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
90.
Brian T. Story Michael A. Urynowicz Drew W. Johnson Jessica A. Morris 《Canadian Metallurgical Quarterly》2009,135(1):87-95
Researchers used column and flume experiments with uniform silica sand with and without suspended solids to examine the extent and longevity of hydraulic conductivity reduction (HCR) resulting from three anionic polyacrylamide (PAM) application methods, liquid injection, slurry surface, and granular surface application. Low turbidity (0.4 NTU) liquid injection column tests showed 20–65% HCR, likely caused by an extensional viscosity mechanism. HCR increased as turbidity increased, especially at low PAM concentrations. High turbidity (100 NTU) liquid injection column tests showed 66–77% HCR, likely through surficial PAM–clay aggregate filtration. Column and adsorption tests strongly suggest PAM–sand adsorption does not cause substantial HCR. In low turbidity flume tests, PAM slurry application to the sand surface produced up to 100% HCR, likely through a viscosity mechanism, and granular application to the media surface produced up to 100% HCR, likely through fixed surficial polymer gel formation. Hydraulic conductivity returned to control-adjusted pretreatment levels following PAM application in all tests except granular surface application at high mass loads or with high turbidity. 相似文献