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41.
It has been proposed that the current design of in-vehicle displays may not be appropriate for the older driver. This paper describes an empirical, road-based investigation of the benefits to older and younger drivers of providing landmarks within the instructions presented by an in-vehicle navigation system. Thirty two participants navigated a challenging urban route using either landmarks or distance information to identify the location of forthcoming manoeuvres. A range of driver behaviour measures were collected, including visual glance data, driving errors, driver workload, navigation errors, navigation confidence, and pre and post-trial driver attitudinal responses. Results show that, for older and younger drivers, landmarks reduced the time spent glancing to a visual display, reduced navigation and driving errors, and influenced driver confidence. There were some key differences between the older and younger drivers. The wider implications for the design of in-car interfaces for the older driver are discussed. 相似文献
42.
Xin Miao Peng Gong Sarah Swope Ruiliang Pu Raymond Carruthers Gerald L. Anderson Jill S. Heaton C.R. Tracy 《Remote sensing of environment》2006,101(3):329-341
The invasive weed yellow starthistle (Centaurea solstitialis) has infested between 4 and 6 million hectares in California. It often forms dense infestations and rapidly depletes soil moisture, preventing the establishment of other species. Precise assessment of its canopy cover, especially low-density abundance in the earlier growing season, is the key to effective management. Compact Airborne Spectrographic Imager 2 (CASI-2) hyperspectral imagery was acquired at the western edge of California's Central Valley grasslands on July 15, 2003. Four linear spectral mixture models (LSMM) were investigated from the original CASI-2 data. Band selections based upon residual analysis and feature extraction (PCA) were further explored to reduce the data dimension. All approaches, except four band-selection unconstrained LSMMs, provide consistent results. The uncertainty of the PCA-based LSMM was estimated through a Monte-Carlo simulation. The maximum standard deviation was approximately 11%. The results suggest that unmixing CASI-2 imagery could be used for estimating and mapping yellow starthistle for larger regional areas. 相似文献
43.
Bigler Erin D.; Johnson Sterling C.; Anderson Carol V.; Blatter Duane D.; Gale Shawn D.; Russo Antonietta A.; Ryser David K.; Macnamara Susan E.; Bailey Becky J.; Hopkins Ramona O.; Abildskov Tracy J. 《Canadian Metallurgical Quarterly》1996,10(3):333
In traumatically brain-injured (TBI) patients (n?=?83), memory performance was examined on the Warrington Recognition Memory Test, Rey-Osterrieth Complex Figure, and the Logical Memory and Visual Reproduction subtests of the Wechsler Memory Scale-Revised in relationship to time postinjury and structural changes based on MRI volumetry, including hippocampus volume. Significant trauma-induced changes were observed, including hippocampal atrophy. Structure-function relationships generally became significant only after 90 days postinjury. Memory tended to relate more to the degree of hippocampal atrophy, particularly left hippocampus, than to nonspecific indicators such as the temporal horns or the ventricle-to-brain ratio. A stronger relationship with left versus right hippocampus was evident for measures of verbal and supposedly nonverbal memory. These results are discussed with regard to the role the hippocampus may play in a neural system of memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
KR Korzekwa N Krishnamachary M Shou A Ogai RA Parise AE Rettie FJ Gonzalez TS Tracy 《Canadian Metallurgical Quarterly》1998,37(12):4137-4147
Some cytochrome P450 catalyzed reactions show atypical kinetics, and these kinetic processes can be grouped into five categories: activation, autoactivation, partial inhibition, substrate inhibition, and biphasic saturation curves. A two-site model in which the enzyme can bind two substrate molecules simultaneously is presented which can be used to describe all of these observed kinetic properties. Sigmoidal kinetic characteristics were observed for carbamazepine metabolism by CYP3A4 and naphthalene metabolism by CYPs 2B6, 2C8, 2C9, and 3A5 as well as dapsone metabolism by CYP2C9. Naphthalene metabolism by CYP3A4 and naproxen metabolism by CYP2C9 demonstrated nonhyperbolic enzyme kinetics suggestive of a low Km, low Vmax component for the first substrate molecule and a high Km, high Vmax component for the second substrate molecule. 7, 8-Benzoflavone activation of phenanthrene metabolism by CYP3A4 and dapsone activation of flurbiprofen and naproxen metabolism by CYP2C9 were also observed. Furthermore, partial inhibition of 7, 8-benzoflavone metabolism by phenanthrene was observed. These results demonstrate that various P450 isoforms may exhibit atypical enzyme kinetics depending on the substrate(s) employed and that these results may be explained by a model which includes simultaneous binding of two substrate molecules in the active site. 相似文献
45.
RC Becker CP Cannon EG Bovill RP Tracy B Thompson GL Knatterud A Randall B Braunwald 《Canadian Metallurgical Quarterly》1996,78(2):142-147
The records of 60 patients with gallbladder carcinoma (GBC) operatively treated between 1966 and 1993 at Belen Hospital, Trujillo, Perú, were retrospectively reviewed. The ratio of men to women was 1:7.5 and the average of age was 61 years. The accuracy of ultrasonography and oral cholecystograms for the specific diagnosis was 21% and 0% respectively. The surgical procedures employed were simple cholecystectomy (n = 56), right hepatectomy (n = 2). Whipple operation (n = 1) and extended cholecystectomy (n = 1), and our resectability rate for GBC is currently 50%. Simple cholecystectomy was a potentially curative surgical procedure in patients with in situ cancer (stage O) and early GBC (stage 1). In hospital mortality was 11.6% and 5-year survival rate for the total series was 15%. Gallstones were present in 95% of patients and most tumors (58%) had grown by diffuse infiltration or were associated with empyema (38%). Tumor stage, depth of invasion, tumor grade histologic type were all predictive of patient outcome. This report reinforces the difficulty in diagnosis and the poor prognosis for patients with GBC. We hold the view that more radical approaches for invasive cancers will enhance the operative results. 相似文献
46.
Texture and microstructure of thin copper films 总被引:1,自引:0,他引:1
Microstructure is an important factor influencing the reliability of thin film interconnects. The microstructure of copper
films is of particular interest because of its use in numerous electronic applications. Pole figure x-ray diffraction and
transmission electron microcopy were conducted on copper films deposited by several techniques: sputtering, partially ionized
beam deposition, chemical vapor deposition, evaporation, and electroplating. Quantitative texture data are determined from
fiber texture plots. A typical copper film consists of three texture components: (111), (200), and random. (220) and (511)
texture components are possible under some deposition conditions. Compared to aluminum films, the fraction of the random texture
component and the distribution of the (hkl) components in copper films are relatively large. Bimodal grain size distributions
are observed in some films. 相似文献
47.
Punshon T Bertsch PM Lanzirotti A McLeod K Burger J 《Environmental science & technology》2003,37(9):1766-1774
An X-ray microprobe was used to determine the concentration and distribution of Ni, U, and other metals within annual rings of willows (Salix nigra L.) from a former de facto radiological settling basin (Steed Pond; SP) and a depositional environment downstream (Tims Branch; TB) on the Savannah River Site (SRS). Geochemical and historical information about both areas are well documented. Following spillway breaches at SP in 1984 and the early 1990s, TB is inundated with contaminated sediments during storms. Bulk elemental composition of tree cores was determined using ICP-OES. Synchrotron X-rayfluorescence (SXRF) analysis showed that the metal contents of SP and TB cores were an order of magnitude higher than those from a reference site. TB cores were enriched with Ni in 1984 and 1991, corresponding with SP spillway breaches (containing 790 mg kg(-1) Ni in 1991). Cores from SP exhibited an extremely high Ni peak in 1996, approximately 5000 mg kg(-1), even though contaminant levels at SP did not change. The geochemical signature of contaminants recorded in TB annual rings reflected the significant sediment remobilization events consistent with the detailed history of the site, and at concentrations relative to their proximity to the source term. However, physiological processes occurring within impacted trees strongly influence the chronological accuracy of dendroanalysis and must be investigated further. 相似文献
48.
The efficacy levels of practices used by consumers to wash smooth-surface fruits and vegetables were compared. Golden Delicious apples were spot inoculated near the blossom end with 50 microl of a cocktail of six serotypes of Salmonella enterica (with a total inoculum level of approximately 10(9) CFU per apple). The inoculum was dried for 1.5 h, and apples were either treated immediately or held for 24 h prior to treatment. Treatments included wetting with approximately 5 ml of water, vinegar (5% acidity), or a 200-ppm chlorine solution, rubbing for 5 or 30 s, rinsing with 200 to 600 ml of 24 or 43 degrees C water, and drying with a sterile paper towel. Residual populations of Salmonella were determined by rubbing the treated apple for 30 s in 20 ml of Dey-Engley neutralizing broth and plating on tryptic soy agar and bismuth sulfite agar. Rubbing treatments carried out for 5 and 30 s both resulted in a significant reduction in Salmonella populations (1 log10 CFU per apple) relative to populations on samples held for 30 s. A 5-s rub followed by a 200-ml flowing-water rinse reduced populations by 3 log10 CFU per apple. No further decrease in population was obtained by rinsing with 400 or 600 ml of water. Increasing the rinse water temperature to 43 degrees C did not significantly improve microbial removal. Drying the apple with a sterile paper towel resulted in an additional decrease of approximately 0.4 log10 CFU per apple. A reduction of 3.2 log10 CFU was achieved with a combination of wetting with water, rubbing for 5 s, rinsing with 200 ml of water, and drying with a paper towel for apples inoculated just prior to or 24 h before treatment. Reductions obtained for apples treated with 5% vinegar and with a 200-ppm chlorine solution were significantly larger (2.1 to 3.2 log10 CFU per apple, respectively) than those achieved with water. 相似文献
49.
Andrew?J.?MayEmail author Tracy?Ross Steven?H.?Bayer Mikko?J.?Tarkiainen 《Personal and Ubiquitous Computing》2003,7(6):331-338
Recent years have seen an increased interest in navigational services for pedestrians. To ensure that these services are successful, it is necessary to understand the information requirements of pedestrians when navigating, and in particular, what information they need and how it is used. A requirements study was undertaken to identify these information requirements within an urban navigation context. Results show that landmarks were by far the most predominant navigation cue, that distance information and street names were infrequently used, and that information is used to enable navigation decisions, but also to enhance the pedestrians confidence and trust. The implications for the design of pedestrian navigation aids are highlighted. 相似文献
50.
Hourihan Kathleen L.; Goldberg Samantha; Taylor Tracy L. 《Canadian Metallurgical Quarterly》2007,61(2):91
This study examined whether spatial location mediates intentional forgetting of peripherally presented words. Using an item-method directed forgetting paradigm, words were presented in peripheral locations at study. A recognition test presented all words at either the same or a different location relative to study. Results showed that while recognition of Remember words was unaffected by test location, when Forget words were presented in the same location at test as at study, recognition accuracy was significantly greater than when presented in a different location. Experiment 2 showed that the speed to localize a previously studied word was faster when it was presented in the same rather than a different study-test location but that the magnitude of this spatial priming was unaffected by memory instruction. We suggest that the location of peripherally presented words is represented in memory and can aid the retrieval of poorly encoded words. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献