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991.
992.
Paprika from the region of La Vera (Cáceres) is prepared using a particular process of mild, slow drying in traditional drying barns heated by oakwood fires. This makes it possible for the fruit to maintain its natural components at the same time as contributing certain organoleptic characteristics that are highly appreciated by consumers. We analyzed the changes in the aromatic fraction that occur over the course of this traditional drying technology, using dynamic head space as the isolation method and gas chromatography–mass spectrometry as the identification system. We identified 96 compounds, 55 of which presented significant differences (P < 0.05) between different days of the drying process. Some 40% of the aromatic potential of the end product corresponded to volatile compounds that appeared during the drying process, originating from the wood smoke or as the result of typical reactions of the dehydrated products. 相似文献
993.
V. CAVILLOT C. PIERART M. KERVYN DE MEERENDRÉ M. VINCENT M. PAQUOT J. WOUTERS C. DEROANNE S. DANTHINE 《Journal of Food Lipids》2009,16(3):273-286
Physicochemical properties of commercially available European bakery margarines (cream margarines, cake margarines [CM] and puff pastry margarines [PPM]) containing and devoid of trans fatty acids (TFAs) were investigated. Studied physical properties were the solid fat content (SFC), dropping points (DPs), polymorphism, texture (hardness), plasticity and the melting profile by differential scanning calorimetry. Experimental results confirm that physical properties of the margarines corresponded with their application area. For example, SFC and DPs of PPM were higher than cream margarines and CM; they were also harder at 15C. Moreover, all the investigated physical properties were affected by the suppression of TFA in bakery margarines .
This study has shown that margarines present different physical properties with respect to their purposed application but also highlight changes that appear due to the absence of trans-fatty acids in the formulations. These changes can really affect the bakery abilities and will, finally, influence the quality of the bakery products. 相似文献
PRACTICAL APPLICATIONS
This study has shown that margarines present different physical properties with respect to their purposed application but also highlight changes that appear due to the absence of trans-fatty acids in the formulations. These changes can really affect the bakery abilities and will, finally, influence the quality of the bakery products. 相似文献
994.
G. DE LA FUENTE-BETANCOURT F. GARCÍA-CARREÑO M.A. NAVARRETE DEL TORO J.H. CÓRDOVA-MURUETA 《Journal of Food Biochemistry》2009,33(2):260-272
Evaluation of the effect of pH (2 to 13) and temperature (0 to 50C) on functional properties of jumbo squid proteins was performed, followed by a 2 × 3 factorial design for producing squid protein hydrolysates bearing useful functional properties. In particular, the effects of pH (8, 9 and 10) and temperature (30, 35, 40C) were evaluated. Alcalase and papain were tested on each treatment. The protein recovery, whippability and emulsifying capacity of the hydrolysates were evaluated. Almost 80% of the proteins were recovered in water-soluble form after hydrolysis with papain at pH 10 at the three temperatures. The highest values of whippability (245 ± 17.7%), foam stability (100%), emulsion-forming capacity (27 ± 0.97%) and stability (99.99 ± 8.8%) occurred with papain-produced hydrolysates. When squid protein was treated at 50C and pH 8, the highest whippability value (390.0 ± 0.1%) and foam stability (100%) were obtained when no enzyme was added.
This paper assesses how process variables, particularly temperature and pH, affect the functional properties of squid proteins. Making use of such process variables will produce more useful and efficient processes, as the application of a hydrolysis system. The processing of jumbo squid protein to obtain proteins bearing adequate functional properties would be an inexpensive way to provide added value to this marine resource and the production of a high-quality protein ingredient. These results hold promise for jumbo squid proteins as useful food ingredient because of their functional properties. 相似文献
PRACTICAL APPLICATIONS
This paper assesses how process variables, particularly temperature and pH, affect the functional properties of squid proteins. Making use of such process variables will produce more useful and efficient processes, as the application of a hydrolysis system. The processing of jumbo squid protein to obtain proteins bearing adequate functional properties would be an inexpensive way to provide added value to this marine resource and the production of a high-quality protein ingredient. These results hold promise for jumbo squid proteins as useful food ingredient because of their functional properties. 相似文献
995.
Rousseau Vincent; Salek Salwa; Aubé Caroline; Morin Estelle M. 《Canadian Metallurgical Quarterly》2009,14(3):305
Recent research has demonstrated that the perception of injustice at work may increase psychological health-related problems. The purpose of this study is to examine the moderating effect of coworker support and work autonomy on the relationships between both distributive and procedural justice and psychological distress. Results, on the basis of responses to questionnaires given to 248 prison employees, show that coworker support moderates the relationships between both forms of justice and psychological distress. Specifically, these relationships are weakened when employees benefit from a high level of coworker support. Furthermore, work autonomy moderates the relationship between procedural justice and psychological distress but not the relationship between distributive justice and psychological distress. Thus, procedural injustice is less likely to increase psychological distress when the level of work autonomy is high. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Bioleaching of an organic-rich polymetallic concentrate using stirred-tank technology 总被引:1,自引:0,他引:1
P. Spolaore C. Joulian J. Gouin A. Ibez T. Aug D. Morin P. d'Hugues 《Hydrometallurgy》2009,99(3-4):137-143
The bioleaching of a concentrate produced from a black shale ore in an industrial operation in Poland was assessed. Following preliminary batch culture tests, processing in continuous conditions was tested to determine the main specifications for the application of the stirred-tank technology to this organic-rich polymetallic concentrate.The experimental work was carried out in a laboratory-scale unit consisting of three stirred tanks (50 L or 20 L) using an acidophilic and moderate thermophilic (42 °C) bacterial population. Different configurations of the unit and key operating parameters were tested (nutrient medium composition, solids concentration, agitation and aeration rates). The analysis of both bacterial community structure and mineralogical characteristics of the concentrate and the bioleach residues were implemented in order to better understand the chemical and biochemical reactions occurring in the system. Using the data produced during the continuous operation, downstream processing assessment for both copper and silver recovery was also carried out.The best copper recovery obtained in the continuous operation was 92% and hot brine leaching of the bioleaching residue (PLINT Process) permitted the recovery of 92% of the silver. Copper and silver recoveries seemed to be limited by incomplete chalcopyrite dissolution. A preliminary techno-economical evaluation of the concentrate bioleach processing, including bioleaching and copper and silver recoveries, demonstrated the potential economical feasibility. Silver recovery plays an important role in the process's finances. This study presents promising results that encourage further investigation of bioleach processing. 相似文献
997.
998.
999.
COLD-CONDITIONING TREATMENT REDUCES CHILLING INJURY IN MEXICAN LIMES (CITRUS AURANTIFOLIA S.) STORED AT DIFFERENT TEMPERATURES 总被引:1,自引:0,他引:1
FERNANDO RIVERA CLARA PELAYO-ZALDIVAR FERNANDO DÍAZ DE LEÓN BEATRIZ BUENTELLO MANUEL CASTILLO-RIVERA LAURA J. PÉREZ-FLORES 《Journal of food quality》2007,30(1):121-134
Induction of different antioxidant enzymes by high and low temperatures prior to storage has been reported to produce tolerance to chilling injury (CI). Thus, different prestorage temperatures have been suggested to decrease CI in citrus fruits. In this work, the effectiveness of a cold‐conditioning treatment (13C for 48 h) to prevent CI was evaluated in Mexican limes (Citrus aurantifolia S.) stored at 4, 10 and 25C, and 90% relative humidity. Cold conditioning reduced 1.6‐fold CI symptoms, induced a significant increase of 2.2‐fold peroxidase activity and maintained the activity of superoxide dismutase in limes kept at 4C. Our results suggest that the effectiveness of the cold‐conditioning treatment in increasing chilling tolerance in Mexican limes depends on the induction or maintenance of antioxidant enzymatic systems during the entire storage period. 相似文献
1000.
The objective of this study was to identify herd-level colostrum management factors associated with the adequate transfer of passive immunity (TPI; defined as serum Brix refractance ≥8.4% in the first week of life). A total of 59 commercial Holstein dairy farms were included in this observational cross-sectional study. In every participating herd, a minimum of 14 Holstein calves were sampled to measure their TPI using a digital Brix refractometer. Colostrum samples fed to each of these calves were collected to estimate IgG concentration (colostrum quality) using a digital Brix refractometer and bacterial contamination using the Petrifilm (3M, St. Paul, MN) culture system. Dairy producers completed a questionnaire on colostrum management to assess on-farm practices. The study outcome was the prevalence of adequate TPI calculated based on the proportion of adequate TPI (defined with an individual threshold ≥8.4% Brix) on the total samples tested within each herd. According to the threshold determined in a previous study investigating the influencing colostrum management factors to achieve adequate TPI at the calf level, the prevalence of an adequate colostrum volume fed at first meal (≥2.5 L), the prevalence of adequate colostrum quality (≥24.5% Brix), the prevalence of an adequate time to first feeding (delay between birth and the first colostrum meal, ≤3 h), the prevalence of low aerobic bacterial contamination (≤20,000 cfu/mL), the prevalence of low coliform contamination (≤1,000 cfu/mL), and the prevalence of females were calculated. The herd-level prevalence of adequate TPI ranged from 24% to 100%, with a median of 68%. The median herd prevalences of an adequate colostrum volume fed at first meal, of adequate colostrum quality, of an adequate time to first feeding, of low aerobic bacterial contamination, of low coliform contamination, and of females, were 71, 42, 41, 64, 88, and 61%, respectively. In the final model, the prevalence of adequate TPI was associated with the prevalence of an adequate colostrum volume fed at first meal and the prevalence of an adequate time to first feeding. In summary, management practices varied greatly between farms and influenced the prevalence of adequate TPI. 相似文献