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121.
For large software companies, the sheer number of textual requirements presents specific challenges. To find market opportunities, organizations must continuously elicit new requirements and reevaluate old ones as market needs evolve. Developing large, complex software products aimed at broad markets involves identifying and maintaining the link between product requirements and the massive inflow of customers' wishes. Automating this support through linguistic engineering could save considerable time and improve software quality. 相似文献
122.
Study on the Implementation of Optical Transparent Transport Networks in the European Environment—Results of the Research Project COST 239 总被引:1,自引:0,他引:1
Batchelor Peter Daino Benedetto Heinzmann Peter Hjelme Dag R. Inkret Robert Ja¨ger Hubert A. Joindot Michel Kuchar Anton Coquil Emile Le Leuthold Peter Marchis Giancarlo De Matera Francesco Mikac Branko Nolting Hans-Peter Spa¨th Jan Tillerot Fran¸ois Caenegem Bart Van Wauters Nico Weinert Carl 《Photonic Network Communications》2000,2(1):15-32
Photonic Network Communications - 相似文献
123.
Physical, chemical and palynological characterization of avocado (Persea americana Mill.) honey in Israel 总被引:1,自引:0,他引:1
Arnon Dag Ohad Afik Yelena Yeselson Arthur Schaffer & Sharoni Shafir 《International Journal of Food Science & Technology》2006,41(4):387-394
Various methods were used to characterize avocado honey in Israel. Perseitol, a unique sugar present only in avocado honey, served as an indicator for the degree of purity of avocado honey. Low avocado pollen counts made the common melissopalynology method ineffective at predicting the contribution of avocado nectar to honey. It was also found that the levels of fructose, sucrose and glucose do not uniquely characterize avocado honey. Potassium content and eight other minerals were linearly highly correlated to perseitol content. Moreover, pH level, absorbance and degree of darkness were significantly correlated to perseitol content, and can therefore be used to characterize avocado honey. 相似文献
124.
125.
Dag Myrhaug Olav H. Slaattelid 《Journal of Wind Engineering & Industrial Aerodynamics》1999,80(3):227-252
The paper presents the wind shear stress on the sea surface as well as the velocity profile in stably stratified atmospheric boundary layer flow over wind waves by using similarity theory. For a given geostrophic velocity, Coriolis parameter, spectral peak period and stratification parameter, the sea surface shear stress is determined. Further, the direction of the sea surface shear stress and the velocity profile are given. Parameterizations of the results are also presented. Finally, the engineering relevance of the results is discussed, and, if the wind velocity at the 10 m elevation is available, a simplified method of calculating the sea surface shear stress is given. 相似文献
126.
Dag Henning 《Energy》1997,22(12):1135-1150
MODEST, an energy-system optimisation model is described. It has been applied to a typical local Swedish electricity and district-heating utility and to the national power system. Present and potential installations and energy flows should be considered and their best combination can be obtained through optimisation. MODEST uses linear programming to minimise the capital and operation costs of energy supply and demand-side management. Seasonal, weekly, and diurnal variations of, for example, demand, costs, and capacities are considered. MODEST may be used to decide which investments to make, the dimensioning of new installations, and the operation of all system components. The municipal utility under study should now expand its heat production using woodchips. Electricity export or nuclear phase-out will probably raise the Swedish electricity prices. In this case, cost minimisation is achieved by introducing combined heat and power (CHP) production in the municipality. Fossil fuels should be used in the cogeneration plant at current taxation levels but biofuels are favourable if higher environmental fees are imposed for CO2 emissions. Biomass capacity expansion could decrease local CO2 emissions by 80%. Efficiency improvements for electricity use have robust profitability at high electricity prices. The Swedish electricity demand may be satisfied without nuclear power and fossil fuels through massive biomass use, wind-power supply, and energy conservation. 相似文献
127.
Dag T. Wisland Mats E. Høvin Tor S. Lande 《Analog Integrated Circuits and Signal Processing》2004,41(2-3):209-222
This paper describes a novel noise-shaping Δ-Σ modulator for D/A-conversion which has no global feedback. The proposed topology is well suited for a pipelined clocking scheme allowing increased oversampling ratios for both first and higher order modulators. The maximum clock-frequency of the new modulator is limited only by the delay through one single accumulator regardless of modulator order, which represents a huge saving compared to the conventional modulator. The converter is very modular and scales easily to higher modulator orders. Still the proposed topology is mathematically equivalent to the classical Δ-Σ modulator. Theoretical analysis and circuit simulations for a first- and second-order modulator are presented. The first-order circuit has been implemented in a FPGA-circuit from Altera and measured results are presented. 相似文献
128.
Biochemical Characterization of Turkish Extra Virgin Olive Oils from Six Different Olive Varieties of Identical Growing Conditions
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Cagdas Dag Ilknur Demirtas Ibrahim Ozdemir Somer Bekiroglu Erdal Ertas 《Journal of the American Oil Chemists' Society》2015,92(9):1349-1356
Extra virgin olive oils were extracted from six different major olive cultivars (Gemlik, Ayvalik, Domat, Akhisar, Memecik, Arbequina) cultivated in the Aegean region of Turkey. Fatty acid, sterol and tocopherol compositions were analyzed and the results were compared by multivariate statistical analysis. Olive samples were collected from the same orchard in order to limit the contribution of parameters such as climate, soil quality and agricultural practices to the total variance of chemical composition of olive oils. Principal component analysis (PCA) showed that cultivars can be clearly distinguished on the basis of fatty acid and sterol composition. It is of interest to note that palmitoleic acid content of Arbequina, a Spanish cultivar, is significantly (p < 0.05) higher than the local Turkish cultivars in question and it is the only olive sample whose palmitoleic acid concentration is higher than that of the stearic acid concentration, exhibiting a divergent composition from the local Turkish cultivars. β‐Sitosterol and Δ5‐avenasterol contents of the oils are significantly correlated (r = ?0.989, p < 0.05) and this results in a discriminative axis on the PCA loading plot. Tocopherol composition was relatively insufficient in discriminating the olive varieties. Regarding tocopherol compositions Gemlik cultivar is distinguished from other cultivars with its γ‐tocopherol content, which is in average two times higher than that of other cultivars. The result of the present compositional study provides important data which can be used for olive oil authenticity studies in Turkey. 相似文献
129.
Monsen Jon T.; Hagtvet Knut A.; Havik Odd E.; Eilertsen Dag E. 《Canadian Metallurgical Quarterly》2006,18(2):165
This study assessed the construct validity of the circumplex model of the Inventory of Interpersonal Problems (IIP-C) in Norwegian clinical and nonclinical samples. Structure was examined by evaluating the fit of the circumplex model to data obtained by the IIP-C. Observer-rated personality disorder criteria (DSM-IV, Axis II) were used as external correlates. The reliability of the IIP-C scales was acceptable and in the same range as in the original version. A multisample analysis strategy did not support an invariant circumplex model across the 2 groups. However, the estimated structures reflected mostly the same circular pattern of a quasi-circumplex model in the 2 groups. Departures from the ideal model were of negligible practical significance. The validity results examining personality disorder correlates of the IIP-C generally conformed to predictions, providing direct evidence for agreement between self-report and expert judgments of interpersonal problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
130.
Arnon Dag Eric Ben‐David Zohar Kerem Alon Ben‐Gal Ran Erel Loai Basheer Uri Yermiyahu 《Journal of the science of food and agriculture》2009,89(11):1871-1878
BACKGROUND: Macronutrients play fundamental roles in processes affecting olive oil productivity and are expected to influence oil composition. A necessary step in optimal nutrient application management for olives is an understanding of the relationship between olive tree nutritional status and oil quality parameters. We studied the independent effects of N, P and K concentrations in irrigation solution on the oil quality of ‘Barnea’ olives by applying a wide range of macronutrient concentrations under highly controlled conditions. RESULTS: Oil composition was significantly influenced by P and N levels, while K levels had only a minor effect. Unsaturation levels were unaffected by the treatments but, within the unsaturated fatty acids, the levels of PUFA increased compared to those of MUFA. Specifically, levels of the MUFA C18:1, polyphenol content and peroxide values decreased while levels of the PUFA C18:3 increased in response to higher doses of N and P. CONCLUSION: Decreased MUFA and polyphenol levels coupled with increased omega‐3 levels demonstrated a potential negative influence on oil profile alongside increased nutritional benefits. The sum effects on oil yield and composition should be considered in designing of nutrient application management strategies for olive orchards. Copyright © 2009 Society of Chemical Industry 相似文献