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91.
92.
Netemeyer Richard G.; Maxham James G. III; Lichtenstein Donald R. 《Canadian Metallurgical Quarterly》2010,95(3):530
Based on emotional contagion theory and the value–profit chain literatures, the present study posits a number of hypotheses that show how managers in the small store, small number of employees retail context may affect store employees, customers, and potentially store performance. With data from 306 store managers, 1,615 store customer-contact employees, and 57,656 customers of a single retail chain, the authors examined relationships among store manager job satisfaction and job performance, store customer-contact employee job satisfaction and job performance, customer satisfaction with the retailer, and a customer-spending-based store performance metric (customer spending growth over a 2-year period). Via path analysis, several hypothesized direct and interaction relations among these constructs are supported. The results suggest implications for academic researchers and retail managers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Charles A. Cravotta III Robin A. Brightbill Michael J. Langland 《Mine Water and the Environment》2010,29(3):176-199
Acidic mine drainage (AMD) from legacy anthracite mines has contaminated Swatara Creek in eastern Pennsylvania. Intermittently
collected base-flow data for 1959–1986 indicate that fish were absent immediately downstream from the mined area where pH
ranged from 3.5 to 7.2 and concentrations of sulfate, dissolved iron, and dissolved aluminum were as high as 250, 2.0, and
4.7 mg/L, respectively. However, in the 1990s, fish returned to upper Swatara Creek, coinciding with the implementation of
AMD treatment (limestone drains, limestone diversion wells, limestone sand, constructed wetlands) in the watershed. During
1996–2006, as many as 25 species of fish were identified in the reach downstream from the mined area, with base-flow pH from
5.8 to 7.6 and concentrations of sulfate, dissolved iron, and dissolved aluminum as high as 120, 1.2, and 0.43 mg/L, respectively.
Several of the fish taxa are intolerant of pollution and low pH, such as river chub (Nocomis micropogon) and longnose dace (Rhinichthys cataractae). Cold-water species such as brook trout (Salvelinus fontinalis) and warm-water species such as rock bass (Ambloplites rupestris) varied in predominance depending on stream flow and stream temperature. Storm flow data for 1996–2007 indicated pH, alkalinity,
and sulfate concentrations decreased as the stream flow and associated storm-runoff component increased, whereas iron and
other metal concentrations were poorly correlated with stream flow because of hysteresis effects (greater metal concentrations
during rising stage than falling stage). Prior to 1999, pH < 5.0 was recorded during several storm events; however, since
the implementation of AMD treatments, pH has been maintained near neutral. Flow-adjusted trends for 1997–2006 indicated significant
increases in calcium; decreases in hydrogen ion, dissolved aluminum, dissolved and total manganese, and total iron; and no
change in sulfate or dissolved iron in Swatara Creek immediately downstream from the mined area. The increased pH and calcium
from limestone in treatment systems can be important for mitigating toxic effects of dissolved metals. Thus, treatment of
AMD during the 1990s improved pH buffering, reduced metals transport, and helped to decrease metals toxicity to fish. 相似文献
94.
ANTON L. SCHORNO FRANK A. MANTHEY CLIFFORD A. HALL III 《Journal of Food Processing and Preservation》2010,34(1):167-179
Experiments were conducted to determine the effect of sample size and particle size on lipid oxidation of milled flaxseed. An initial experiment showed that most of the lipid oxidation detected in milled flaxseed samples occurred on the surface that was exposed to the air during storage. In a subsequent experiment, milled flaxseed at 100, 200 and 300 g were stored in the dark in rectangular pans for 8, 24 and 48 days at 50C. Lipid oxidation, as determined by surface lipid content, peroxide value and α-linolenic acid content, was lower in the 300 g samples than in the 100 g samples of milled flaxseed. Large versus small samples had less apparent lipid oxidation because of their inherently lower surface to volume ratio. In a third experiment, oxidation was lower in lipid extracted from coarse ( > 600 µm) than fine particles ( < 600 µm), after 48 days of storage.
This research has practical applications to the flaxseed milling and food industries. These results show that assessment of lipid oxidation in milled flaxseed needs to consider sample size (collection). Milled flaxseed oxidized predominantly at the sample surface where a polymerized layer of flaxseed particles formed over time. Relatively little oxidation occurred in the interior of the sample. Thus, sampling from the surface or interior of a milled flaxseed sample will end in different results and conclusions. Similarly, results will vary with surface : interior ratio of milled flaxseed. Food manufacturers may want to discard the top layer of milled flaxseed that has been exposed to air. Lipid oxidation was less with coarse than fine particles. Thus it would be prudent not to use milled flaxseed with a finer particle size than is necessary for acceptable end-use quality. 相似文献
PRACTICAL APPLICATIONS
This research has practical applications to the flaxseed milling and food industries. These results show that assessment of lipid oxidation in milled flaxseed needs to consider sample size (collection). Milled flaxseed oxidized predominantly at the sample surface where a polymerized layer of flaxseed particles formed over time. Relatively little oxidation occurred in the interior of the sample. Thus, sampling from the surface or interior of a milled flaxseed sample will end in different results and conclusions. Similarly, results will vary with surface : interior ratio of milled flaxseed. Food manufacturers may want to discard the top layer of milled flaxseed that has been exposed to air. Lipid oxidation was less with coarse than fine particles. Thus it would be prudent not to use milled flaxseed with a finer particle size than is necessary for acceptable end-use quality. 相似文献
95.
96.
John V. Crues III 《Magma (New York, N.Y.)》1994,2(3):233-236
NMR imaging has become an important diagnostic tool in the evaluation of musculoskeletal disease. However, its ability to evaluate pathogenic mechanisms of disease may eventually have even a greater impact on patient care. NMR imaging has significantly affected our understanding of the clinical significance of meniscal tears and appropriate patient management. It has also extended our understanding of the prevalence and importance of X-ray and arthroscopically occult bone, tendon, and ligament injuries. By knowing the pathogenic mechanisms of disease, we can more reliably diagnose and treat pathology. In particular, many horizontal degenerative tears in older patients may be asymptomatic and are best left in place. Many acute tears may be best treated with immediate meniscal repair. Magnetic resonance (MR) imaging can reliably differentiate these tear types with noninvasive imaging. The ability of MR to detect bone injuries may lead to aggressive early non-weight-bearing therapy on injured bone, thereby preserving the subchondral bone from collapse and the joint from secondary osteoarthrosis. The ability of MRIs to detect and stage degenerative tendonosis of tendons and ligaments, such as the rotator cuff, may lead to arthroscopic decompression or debridement which provides symptomatic relief and may preserve and protect the intact cuff. 相似文献
97.
Qingyuan Zhang Xiangming Xiao Ernst Linder Marie-Louise Smith Fred Baret Berrien Moore III 《Remote sensing of environment》2006,105(3):189-203
In this paper, we present an improved procedure for collecting no or little atmosphere- and snow-contaminated observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. The resultant time series of daily MODIS data of a temperate deciduous broadleaf forest (the Bartlett Experimental Forest) in 2004 show strong seasonal dynamics of surface reflectance of green, near infrared and shortwave infrared bands, and clearly delineate leaf phenology and length of plant growing season. We also estimate the fractions of photosynthetically active radiation (PAR) absorbed by vegetation canopy (FAPARcanopy), leaf (FAPARleaf), and chlorophyll (FAPARchl), respectively, using a coupled leaf-canopy radiative transfer model (PROSAIL-2) and daily MODIS data. The Markov Chain Monte Carlo (MCMC) method (the Metropolis algorithm) is used for model inversion, which provides probability distributions of the retrieved variables. A two-step procedure is used to estimate the fractions of absorbed PAR: (1) to retrieve biophysical and biochemical variables from MODIS images using the PROSAIL-2 model; and (2) to calculate the fractions with the estimated model variables from the first step. Inversion and forward simulations of the PROSAIL-2 model are carried out for the temperate deciduous broadleaf forest during day of year (DOY) 184 to 201 in 2005. The reproduced reflectance values from the PROSAIL-2 model agree well with the observed MODIS reflectance for the five spectral bands (green, red, NIR1, NIR2, and SWIR1). The estimated leaf area index, leaf dry matter, leaf chlorophyll content and FAPARcanopy values are close to field measurements at the site. The results also showed significant differences between FAPARcanopy and FAPARchl at the site. Our results show that MODIS imagery provides important information on biophysical and biochemical variables at both leaf and canopy levels. 相似文献
98.
The Equal Employment Opportunity Commission's 4/5ths rule has been used for over 20 years in applied psychology and employment law. The rule signals that there is adverse impact when the protected group selection ratio is less than 80% of the highest scoring group's selection ratio. We conducted several simulations and found, consistent with some previous management science literature, that the 4/5ths rule often resulted in false-positive readings of adverse impact even when there were no underlying (population) standardized group differences between subgroups. We then incorporated tests of statistical significance and found that adding such tests to the 4/5ths rule eliminated many false-positive indications of adverse impact. We also examined simulated selection systems based on meta-analytic values from the selection literature. The frequency of adverse impact signals from the 4/5ths rule increased markedly relative to simulations with no subgroup population differences. Adding statistical tests mitigated the number of indications of adverse impact to some extent. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
For the past century the autotransformer, or "Korndorfer" starter, has been a standard in the electrical industry. However, for more than the past 30 years the autotransformer starter has been experiencing unexplained "high-voltage stress" failures in typical applications. These failures have been reported on 2400-V starters from South America to 11000-V starters in the North Sea. In most cases, the zero tap or the turns close to the zero tap are involved in the failure. This paper discusses the failure mode and the corrective action that prevents "high-voltage stress" failures. 相似文献
100.
Dennis G. Grubb Atwood F. Davis Steven C. Sands Michael Carnivale III Joseph Wartman Patricia M. Gallagher 《Canadian Metallurgical Quarterly》2006,132(5):577-590
Based on the laboratory results reported in a companion paper, three crushed glass–dredged material (CG–DM) blends were prepared and evaluated in the field to explore the feasibility of using CG–DM blends in general, embankment and structural fill applications. A trailer-mounted pugmill successfully prepared 20/80, 50/50, and 80/20 CG–DM blends (dry weight percent CG content reported first) within a tolerance of ±5 dry % by weight of the targeted percentages. Blending criteria were routinely met at pugmill throughputs up to 1,500?m3/day. The constructed 20/80 CG–DM embankment was compacted to a minimum of 90% modified Proctor compaction, whereas the 50/50 and 80/20 CG–DM embankments were constructed to a minimum of 95% modified Proctor compaction. Twenty to 80% CG addition to DM resulted in 1.5–5.5?kN/m3 increases in field dry densities above 100% DM, densities not achievable with other DM stabilization techniques such as Portland cement, fly ash, and/or lime (PC/FA/lime) addition. CG substantially improved the workability of DM allowing construction with conventional equipment and three person crew while achieving very consistent and reproducible results during a timeline of frequent and heavy precipitation events. The 20/80, 50/50, and 80/20 CG–DM embankments were characterized by average cone tip resistances on the order of 1.0, 1.5, and 2.0?MPa, respectively. An environmental evaluation of 100% CG, DM and 50/50 CG–DM blend samples coupled with an economic analysis of a scaled-up commercial application illustrated that the CG–DM blending approach is potentially more cost effective than PC/FA/lime stabilization approaches. These features of CG–DM blending make the process attractive for use in urban and industrial settings. 相似文献