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131.
Cloning and sequencing of RCS1, Saccharomyces cerevisiae gene whose product seems to be involved in timing the budding event of the cell cycle, is described. A haploid strain in which the 3'-terminal region of the chromosomal copy of the gene has been disrupted produces cells that are, on average, twice the size of cells of the parental strain. The critical size for budding in the mutant is similarly increased, and the disruption mutation is dominant in a diploid heterozygous for the RCS1 gene. Spores from this diploid have a reduced ability to germinate, the effect being more pronounced in the spores carrying the disrupted copy of RCS1. However, disrupted cells recover from alpha-factor treatment equally as well as wild-type cells. 相似文献
132.
Ananías Pascoal Marta Prado Pilar Calo Alberto Cepeda Jorge Barros-Velázquez 《European Food Research and Technology》2005,220(3-4):444-450
The identification of beef in animal foods is a major concern not only for the prevention of commercial fraud, but also to avoid safety risks deriving from the presence of prohibited bovine material that might be harmful to both human and animal health. Here we report a novel set of bovine-specific primers, CYTbos1 (forward) and CYTbos2 (reverse), which allow the specific amplification of a 115 base pair fragment of the bovine cytochrome b gene (cytb) between nt 844 (mitochondrial site 15,590) and nt 958 (mitochondrial site 15,704), no cross-reaction being observed with DNA from another 12 frequent commercial meat species. The polymerase chain reaction product obtained is cleaved specifically by endonucleases ScaI and TspE1 to achieve further confirmation evidence. The sensitivity of the proposed method was 0.025%. The CYTbos primers successfully detected bovine DNA in meat samples processed for 20 min at 133 °C/300 kPa or for 2 h at 121 °C. CYTbos primers also detected bovine DNA in heat-processed commercial meat products exhibiting a complex nature, as well as in bovine specific risk materials. The proposed polymerase chain reaction method, aimed at detecting a small and specific fragment of the bovine mitochondrial DNA, may be especially useful for the direct identification of bovine DNA in foodstuffs subjected to severe heating under overpressure conditions. 相似文献
133.
Ultra‐high‐pressure homogenization (UHPH) system for producing high‐quality vegetable‐based beverages: physicochemical,microbiological, nutritional and toxicological characteristics 下载免费PDF全文
134.
Gloria Urbano Sławomir Frejnagel Jesús M. Porres Pilar Aranda Elena Gomez-Villalva Juana Frías María López-Jurado 《European Food Research and Technology》2007,226(1-2):105-111
The effect of dephytinization of Pisum sativum, L. flour on the bioavailability of Mg and Zn was evaluated in growing rats. Processing of legume flours under optimal conditions
for phytase activity (pH 5.5, 37 °C, 60 min) and subsequent removal of the soaking solution led to a 42 and 61% reduction
in the content of Mg and Zn, respectively. Treatment with phytase led to an additional reduction in the concentration of the
above-mentioned seed flour components, compared to the raw pea flour (69% and 74% for Mg and Zn, respectively). The considerable
reduction in the content of inositol phosphates with high degree of phosphorylation attained under both processing conditions
did not affect the digestive utilization of Mg, whereas the metabolic utilization of this mineral increased significantly.
The digestive and metabolic utilization of Zn increased significantly in response to both processes assayed, reaching the
highest values in the experimental group that was fed the phytase-treated pea flour diet. The amount of Mg retained by the
experimental animals was reflected in the content of this mineral in the different tissues studied (femur, sternum, kidney,
and heart), whereas no correlation was found in the case of Zn. 相似文献
135.
Carmen García-Domingo Pilar Rupérez F. Saura-Calixto 《European Food Research and Technology》1997,204(1):43-47
Profiles of flavonoid compounds of Apis mellifera and Melipona spp. honeys from Venezuela were analysed to evaluate entomological-dependent differences. The presence of ellagic acid was
a characteristic of A. mellifera honeys from Venezuela, but its presence was variable in Melipona spp. samples. The number of flavonoid types present in individual samples did not exceed six and occasionally only one phenolic
type was present. The diversity of flavonoid compounds in tropical honeys from Venezuela was lower than that previously measured
in temperate honeys. Flavonoids such as myricetin, an unidentified chalcone and a flavonol glycoside were only found in Melipona honeys but not in all the samples; therefore, they cannot be foreseen as entomological markers to differentiate between the
Apis and Melipona honeys under study. A preliminary discussion is made regarding flavonoids present in Melipona honeys and their probable link with the putative anticataract action of stingless bee-honeys.
Received: 22 February 1996 相似文献
136.
Pilar Miranzo Eugenio García Cristina Ramírez Jesús González-Julián Manuel Belmonte M. Isabel Osendi 《Journal of the European Ceramic Society》2012,32(8):1847-1854
Silicon nitride (Si3N4) composites containing carbon nanotubes (CNTs) or graphene nanoplateles (GNPs) are of great relevance in the electronic and aerospace industries where the search for new materials with enhanced and anisotropic thermal conductivity to work in harsh environments is a strategic guideline. Here we study thermal conduction in Si3N4 composites with different amounts of carbon nanostructures. The effects of the nanostructure orientation respect the heat flux, the testing temperature and the α/β Si3N4 phase ratio are analyzed. The addition of CNTs and GNPs leads to an anisotropic thermal response, decreasing the through-thickness thermal conductivity of the Si3N4 composites and raising the in-plane thermal conductivity, especially for GNPs that enhance it up to twice that of the monolithic Si3N4. This effect is related to the preferred orientation of the nanostructures that gives a less resistive network in the in-plane direction and the intrinsic anisotropy of their thermal conductivity. 相似文献
137.
The aim of this study was to examine the potency of the antinociceptive effects of the non-steroidal antiinflammatory drug (NSAID), Dexketoprofen Trometamol (the active enantiomer of ketoprofen) on spinal cord nociceptive reflexes. These effects were compared with those of the mu-opioid receptor agonist fentanyl in normal animals. The experiments were performed in male Wistar rats anaesthetised with alpha-chloralose. The nociceptive reflexes were recorded as single motor units in peripheral muscles, activated by mechanical and electrical stimulation. Both dexketoprofen and fentanyl inhibited responses evoked by mechanical and electrical stimulation with doses in the same nanomolar range (dexketoprofen ID50s: 100 and 762 nmol kg-1 and fentanyl: 40 and 51 nmol kg-1, respectively). Dexketoprofen and fentanyl also significantly inhibited wind-up. Since fentanyl has been shown to be some 1000 times more potent than morphine in this type of experiments, we conclude that dexketoprofen has central analgesic actions in normal animals and depresses nociceptive responses with a potency similar to that of mu-opioid agonists. 相似文献
138.
The effect of Cr content on the microstructure and cyclic oxidation behavior of Nb–10W–XCr alloys with four different compositions has been investigated. Experiments were conducted in air at 900 °C and 1300 °C; the oxidation kinetics have been evaluated in terms of weight change per unit area with respect to exposure time. Alloy's microstructure consists of Nb solid solution phase regions surrounded by a network of NbCr2 Laves phase. A trend of improvement in oxidation resistance with increase of the intermetallic phase is observed at 1300 °C and oxidation kinetics follow a parabolic behavior. At 900 °C, alloys with higher Cr content exhibit higher oxidation rates than alloys with lower Cr content. The oxidation products are a mixture of CrNbO4, and Nb2O5 and the amount of each oxide present in the mixture is related to the intermetallic phase content. Results delineate the influence of microstructure and composition on the oxidation mechanisms of these alloys that represent a promising base for high-temperature intermetallic alloy development. 相似文献
139.
Rosa López Isabel López‐Alfaro Ana Rosa Gutiérrez Carmen Tenorio Patrocinio Garijo Lucía González‐Arenzana Pilar Santamaría 《International Journal of Food Science & Technology》2011,46(11):2373-2381
Malolactic fermentation (MLF) of Tempranillo Rioja wines (Spain) inoculated with two lactic acid bacteria (LAB) strains were studied and compared with spontaneous MLF. Inoculation with selected Oenococcus oeni lyophila shortened MLF duration up to 19 days and lead to wines with more fresh and fruity characters, especially when implantation was 100%. We demonstrated modifications in the concentration of volatile and nitrogenous compounds and a good correlation between analytical and sensory attributes was also noted. In addition, the low initial amino acid concentration and the consumption of these compounds by the inoculated yeast strain during alcoholic fermentation resulted in wines with very low biogenic amines levels (under 3.75 mg L?1) after MLF and 3 month storage period in all cases. The results showed the significance of choose the most suitable starter to elaborate quality wines and suggest the control of amino acid content in must and wine to prevent the formation of biogenic amines. 相似文献
140.