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121.
Fish mercury development in relation to abiotic characteristics and carbon sources in a six-year-old, Brazilian reservoir 总被引:3,自引:0,他引:3
Tuomola L Niklasson T de Castro E Silva E Hylander LD 《The Science of the total environment》2008,390(1):177-187
Time series on fish mercury (Hg) development are rare for hydroelectric reservoirs in the tropics. In the central-western part of Brazil, a hydroelectric reservoir, called Lago Manso, was completed in 1999 after that background levels of fish Hg concentrations had been determined. The development for the first 3 years was studied in 2002. The objective of the present study was to determine development of fish Hg concentrations for a second three-year period after flooding. The bioaccumulation factor and certain abiotic and biotic factors, possibly affecting the availability and accumulation of Hg, were also examined. The results show that Hg levels in fish from Lago Manso have increased more than five times compared to the background levels observed before construction of the reservoir. At the same time, dissolved organic carbon has increased while dissolved oxygen has decreased indicating enhanced bioavailability of Hg. In the reservoir, Salminus brasiliensis had in average a Hg content of 1.1 microg g(-1) f.w., Pseudoplatystoma fasciatum 1.2, Serrasalmus marginatus/spilopleura 0.9, and Brycon hilarii 0.6 microg g(-1) f.w. The average fish Hg contents were higher downstream, except for B. hilarii. In the reservoir, the average Hg content of each species was in 2005 always over the consumption limit (0.55 microg total Hg g(-1) f.w.) recommended by WHO. Therefore, the people living around Lago Manso should be informed of the health effects of Hg, and fish consumption recommendations should be carried out. The accumulation of Hg varies widely between species as shown by the bioaccumulation factor which ranges between 5.08 and 5.59 log units. The observed variation is explained by differences in diet and trophic position with piscivorous fish exhibiting the highest mean Hg concentration, followed by carnivorous and omnivorous species. Carbon isotope analyses imply that trophic position is not the only cause of the observed differences in Hg levels between omnivorous B. hilarii, having a diet partly based on C(4) plants, and carnivorous S. marginatus as well as piscivorous S. brasiliensis, whose carbon sources are depleted in (13)C. The fact that the species have different carbon sources indicates that they belong to different food chains. 相似文献
122.
Fruits and vegetables are known as good sources of phytochemicals, essential to prevent degenerative diseases like cancer and cardiovascular diseases (CVD). They contain a variety of antioxidants, which are useful to scavenge radical oxygen species (ROS). Besides smoothies, fruit purees, concentrates and juices - used by the food industry for these new beverages - were analysed. Total phenolics by Folin-Ciocalteu method, vitamin C content and antioxidant capacity (AOC) by FRAP, TEAC and ORAC assay were analysed by using high-throughput methods on a microplate reader. Vitamin C content ranged from 31 ± 3 mg/100 g in drinkable pomegranate concentrate to 1373 ± 125 mg/100 g in acerola puree; total phenolics content was quantified between 51 ± 1 mg gallic acid equivalents (GAE)/100 g in the mango-peach smoothie and 1152 ± 62 mg/100 g in the ascorbic acid rich acerola puree. The AOC differed depending on kind of fruit and antioxidant assay used. In most fruit products the major portion of AOC was generated by polyphenolic compounds, except acerola puree and orange juice. Very good correlations between total phenolics content and antioxidant capacity were found in the single fruit products, however not in the fruit and vegetable smoothies. Most of the analysed smoothies were able to supply with one package nearly the recommended dietary intake (RDI) of vitamin C for adults of 100 mg per day. 相似文献
123.
Lars Henkel Dietmar Koch Georg Grathwohl 《Journal of the American Ceramic Society》2009,92(4):805-811
A new way to prepare magnesia-alumina-spinel was investigated making use of a mixed powder system of MgO and metallic Al-3 wt% Mg. Intensive ball milling was applied which provides the formation of new powder particles as composite of both components in intimate contact. The new configuration of the particles had a significant impact on the reaction sintering behavior leading to single phase spinel microstructures at moderate temperatures below 1400°C. Optimized milling of the powder mixture was therefore required providing reduced crystallite sizes and strongly enlarged interfacial area shared by the reacting components. The optimal milling time was identified by the complete reaction of the starting powders to spinel during sintering. Shorter milling times led to incomplete reactions and longer milling times contaminated the milling product by debris from the milling tools. The amount of interfaces generated by the intimate mixing dominated the sintering reaction kinetics whereas the specific surfaces area was of secondary importance. 相似文献
124.
W. Schreiber Schwaibold G. Steinhoff Beckel J. P. Bruno Roßmann Kanitz W. Ludorff Lars Erlandsen J. Großfeld Schormüller O. Windhausen Amelung H. Mohler Diemair Griebel Sachße E. Tornow W. Wodsak Bäurle C. Pyriki Zacher Jesser Reichard Schönfeld Pauletta Brüning Schloemer Hans Hawelka Kluge R. Grau H. Hanak Roßmann Egger Haevecker E. Dinslage Patzsch K. Müller K. Höll Steinbeck 《European Food Research and Technology》1943,86(5-6):453-568
125.
W. Schreiber Schwaibold Amelung A. Bäurle Großfeld Schormüller J. Ph. Roαmann Diemair Kanitz Pawletta Lars Erlandsen Griebel Beckel E. Dinslage Patzelt W. Hämmerle W. Ludorff Brüning W. Wodsak H. Mohler R. Grau Haevecker Masling O. Windhausen R. Strohecker K. Höll Patzsch K. Dirr Klauditz 《European Food Research and Technology》1943,85(5):441-496
126.
Hahn Griebel W. Schreiber Carls J. Großfeld Steinbeck Beckel Schwaibold Lehnartz Meumann Schormüller Jesser R. Strohecker Lehnartz Diemair R. Grau Lars Erlandson Patzsch Reichard Ph. Bruno Roßmann Brüning Karl Sauer Willy Lindner Kanitz O. Windhausen Schloemer Amelung M. Steiner R. Mancke K. Höll Goreczky E. Tornow Zacher Kleinhans Bäurle 《European Food Research and Technology》1943,85(1):70-112
127.
Schloemer W. Ludorff Beckel Jesser W. Schreiber Lars Erlandsen K. Lang Schwaibold Lehnartz Amelung J. Großfeld E. Tornow Griebel Schormüller A. Bäurle Willy Lindner Diemair Schmitz Zacher A. Dresler Steinbeck Reichard R. Grau Pawletta Schoop W. Wodsak O. Windhausen G. Steinhoff Hawelka J. Ph. Bruno Roßmann Brüning Edmund Baertich Dinslage 《European Food Research and Technology》1943,85(4):348-400
128.
Kanitz Hans Hawelka Schormüller Schwaibold Griebel W. Schreiber Beckel Kortenhaus H. Wenzl Lars Erlandsen Klinc Patzsch Bäurle Diemair Adolf Hanak A. Lendle Pawletta Zacher R. Grau K. Höll Schloemer Jesser W. Wodsak Lindner Masling Haevecker Steinbeck J. Großfeld E. Tornow K. Müller W. Ludorff W. Hämmerle Willy Lindner Brüning O. Windhausen E. Dinslage C. Pyriki Reichard R. Strohecker Spitta Kluge Krzywanek R. Nitsche 《European Food Research and Technology》1942,84(3):230-288
129.
Karl Sauer Diemair E. Dinslage Kanitz Schwaibold Willy Lindner Haevecker Lehnartz E. Becker W. Schreiber Werner Hofmann Eduard Hofmann Steinbeck H. Süllmann Griebel Rudolf Abderhalden Lars Erlandsen Heyns O. v. Soden C. Steinhoff J. Großfeld Frey-Wyssling W. Sutthoff Bäurle Willy Lindner Ed. Rentz Bandow Gerards K. N. v. Kaulla O. v. Soden Maria Cicconi Pawletta Baars R. Grau Lerche Beckel O. Windhausen Felicitas Rolleri Jesser Karl Boresch R. W. Seuffert K. Müller Schloemer K. Höll Johannes Wolf Brüning Patzsch W. Ludorff 《European Food Research and Technology》1941,81(3):223-288
130.
R. Grau Kanitz W. Schreiber Schwaibold Schormüller Rudolf Abderhalden Pawletta Willy Lindner Lars Erlandsen W. Ludorff W. Sutthoff Bäurle G. Steinhoff J. Großfeld Krumbholz Steuber Griebel Kluge Ingeborg Schmidt Steinbeck Beckel Reichard Brüning Haenel H. Mohler Lehnartz Hans Hawelka W. Hämmerle E. Dinslage Patzsch 《European Food Research and Technology》1941,81(6):508-576