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121.
Anthony Moschetti Lucas N. Vine Kyle Lethcoe Ruben K. Dagda Patricia Ellison Robert O. Ryan 《Lipids》2020,55(2):141-149
Coenzyme Q10 (CoQ10) is a strongly hydrophobic lipid that functions in the electron transport chain and as an antioxidant. CoQ10 was conferred with aqueous solubility by incorporation into nanoparticles containing phosphatidylcholine (PtdCho) and apolipoprotein (apo) A-I. These particles, termed CoQ10 nanodisks (ND), contain 1.0 mg CoQ10/5 mg PtdCho/2 mg apoA-I (97% CoQ10 solubilization efficiency). UV/Vis absorbance spectroscopy of CoQ10 ND revealed a characteristic absorbance peak centered at 275 nm. Incorporation of CoQ10 into ND resulted in quenching of apoA-I tryptophan fluorescence emission. Gel filtration chromatography of CoQ10 ND gave rise to a single major absorbance peak and HPLC of material extracted from this peak confirmed the presence of CoQ10. Incubation of cultured cells with CoQ10 ND, but not empty ND, resulted in a significant increase in the CoQ10 content of mitochondria as well as enhanced oxidative phosphorylation, as observed by a ~24% increase in maximal oxygen consumption rate. Collectively, a facile method to solubilize significant quantities of CoQ10 in lipid nanoparticles has been developed. The availability of CoQ10 ND provides a novel means to investigate biochemical aspects of CoQ10 uptake by cells and/or administer it to subjects deficient in this key lipid as a result of inborn errors of metabolism, statin therapy, or otherwise. 相似文献
122.
Lucas Jégo Daniel Milési Jean-Jacques Robin Christine Joly-Duhamel 《Polymer Engineering and Science》2020,60(1):95-103
The photocrosslinking of thick samples of 5-ethylidene-2-norbornene–ethylene propylene diene monomer (ENB-EPDM) under air at room temperature was investigated. First, a model study was carried out on low-molecular weight oligomers: squalene, 1,2-polybutadiene, and 1,4-polybutadiene. Several crosslinking agents (meth(acrylics), bismaleimide, and thiol) combined with various photoinitiators were tested to improve the reactivity of these oligomers under UV irradiation. Gel contents, crosslinking densities, viscosities, and viscoelastic properties were measured in order to characterize the extent of crosslinking. Acrylate-based crosslinking agents appeared to be the most reactive species and these results were then applied to a low-molecular weight EPDM. Several photoinitiators were tested and benzophenone turned out to be the most efficient photoinitiator when combined with trimethylolpropane triacrylate. Finally, a commercial EPDM was subsequently photocrosslinked and high gel content and crosslinking density were obtained after only 2 min of irradiation. POLYM. ENG. SCI., 60:95–103, 2020. © 2019 Society of Plastics Engineers 相似文献
123.
Bacteria, yeasts and filamentous fungi were isolated during natural coffee processing. Bacteria were isolated in greater numbers at the beginning of the fermentation, when the moisture of the coffee beans was around 68%. Gram-positive bacteria represented 85.5% of all bacteria isolated, and Bacillus was the predominant genus (51%). Gram-negative species of the genera Serratia, Enterobacter and Acinetobacter were also found. Approximately 22% of 940 randomly chosen isolates of microorganisms were yeasts. Debaryomyces (27%), Pichia (18.9%) and Candida (8.0%) were the most commonly found genera, and these three genera tended to appear more often as the fruit was fermented and dried. Aspergillus was the most abundant genus besides Penicillium, Fusarium and Cladosporium, with 42.6% of the total fungi isolates. The genera and species identified included members known to have pectinase and cellulase activities. Of the 10 organic acids analyzed and quantified in coffee beans, acetic and lactic acids may have been generated by microbial activity. Butyric acid was not detected in any sample. 相似文献
124.
We examined a range of oenological lactic acid bacteria species and reference strains for their potential to degrade tannins. Bacterial tannase activity was checked by a spectrophotometric and a visual reading method. None of the strains belonging to the oenological species of the genus Lactobacillus, Leuconostoc, Oenococcus or Pediococcus were tannase producers, with the exception of Lactobacillus plantarum. All the L. plantarum strains analyzed were positive for tannase activity and their identities were reconfirmed by L. plantarum PCR-specific assay or by sequencing the 16S rDNA. Tannase activity could be considered an important criterion for the selection of malolactic starter cultures since it might confer advantages in the winemaking process by reducing astringency and haze in wine. 相似文献
125.
Electrical energy metering: Some challenges of the European Directive on Measuring Instruments (MID)
Andrea Bernieri Giovanni Betta Luigi Ferrigno Marco Laracca Rosario Schiano Lo Moriello 《Measurement》2013
The introduction of static electric energy meter together with voltage and current distortions in the electric networks are revolutionizing the measurement of the electrical energy. Several questions and studies are proposed in the scientific literature concerning with metrological and reliability aspects of the actual electrical energy measurement. The European Directive on Measuring Instruments (MID) represents a different spin on setting the performance and safety requirements for those meters. The International Organization of Legal Metrology (OIML) has published the document D11 discussing recommendations for legislation to meet the MID. An OIML technical committee is drafting the recommendation (IR46) that would give regulatory bodies an easily-adoptable set of requirements and tests to meet the requirements of the MID. With the introduction of the MID directive, the actual discussion involves aspects as the metrological characterization of the meters. The paper proposes an analysis of the test settings imposed by the actual MID-harmonized standards, regarding the electric energy metering. The aim is to check the presence of degree of freedom in the test settings that could compromise both result reliability and the compliance/non-compliance of a given apparatus. 相似文献
126.
A rapid and highly specific real-time quantitative PCR, based on the amplification of a fragment of the mitochondrial 12S ribosomal RNA gene (rRNA), has been developed for the quantitation of pork (Sus scrofa) in binary pork/beef muscle mixtures. The method combines the use of pork-specific primers, that amplify a 411bp fragment from pork DNA, and mammalian-specific primers amplifying a 425-428bp fragment from mammalian species DNA, which are used as endogenous control. An internal fluorogenic probe (TaqMan), that hybridizes in the "pork-specific" and also in the "mammalian" DNA fragments is used to monitor the amplification of the target gene. A comparison of the cycle number (C(t)) at which mammalian and pork-specific PCR products are first detected, in combination with the use of reference standards of known pork content, allows the determination of the percentage of pork in a mixed sample. Analysis of experimental pork/beef muscle binary mixtures demonstrated the specificity and sensitivity of the assay for detection and quantitation of pork in the range 0.5-5%. 相似文献
127.
E. A. S. Marques R. D. S. G. Campilho Lucas F. M. da Silva 《Journal of Adhesion Science and Technology》2016,30(7):691-707
The use of adhesives for high-performance structural applications has significantly increased in the last decades. However, the use of adhesive joints in adverse environmental conditions is still limited due to the reduced capability of adhesives to withstand large thermal gradients. Dual adhesive joints, which contain two adhesives with remarkably different mechanical behaviours, are a technique suitable for being used in extreme temperatures. The object of this study is a ceramic–metal joint, representative of the thermal protection systems of some aerospace vehicles. In this paper, several joint-mixed joint geometries are presented, studied with recourse to finite element analysis. In a first phase, the three-dimensional finite element models and the material properties are validated against experimental data. In a second phase, the model geometry is modified, with the aim of understanding the effect of several changes in the joints’ mechanical behaviour and comparing the merits of each geometry. The models’ presented good agreement was found between experimental and numerical data and the alternative geometries allowed the introduction of additional flexibility on the joint but at the cost of lower failure load. 相似文献
128.
Nathan M. Korlesky Lucas J. Stolp Dharma R. Kodali Robert Goldschmidt William C. Byrdwell 《Journal of the American Oil Chemists' Society》2016,93(7):995-1005
Montmorency sour cherry (Prunus cerasus L.) pit oil (CPO) was extracted and characterized by various methods including: GC, LC–MS, NMR, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and X‐ray powder diffraction (XRD). The oil gave an acid value of 1.45 mg KOH/g, saponification value of 193 mg KOH/g and unsaponifiable matter content of 0.72 %. The oil contained oleic (O) and linoleic (l ) acids as the major components with small concentrations of α‐eleostearic acid (El, 9Z,11E,13E‐octadecatrienoic acid) and saturated fatty acid palmitic (P) acid. The CPO contained six major triacyglycerols (TAG), OOO (16.83 %), OLO (16.64 %), LLO (13.20 %), OLP (7.25 %), OOP (6.49 %) and LElL (6.16 %) plus a number of other minor TAG. The TAG containing at least one saturated fatty acid constitute 33 % of the total. The polymorphic behavior of CPO as studied by DSC and XRD confirmed the presence of α, β′ and β crystal forms. The oxidative induction time of CPO was 30.3 min at 130 °C and the thermal decomposition temperature was 352 °C. 相似文献
129.
Vincent Nicolas Fernanda Vanin David Grenier Tiphaine Lucas Christophe Doursat Denis Flick 《American Institute of Chemical Engineers》2016,62(11):3847-3863
A two dimensional model of bread baking was developed including, for the first time, the dependence of dough viscosity on both temperature and moisture content, the carbon dioxide dissolved from liquid water together with gas generation from yeast at the beginning of baking and the shrinkage due to dough drying. Particular attention was paid to experimental validation of both overall and local variables such as local temperature, overall mass loss, and local moisture content, overall CO2 released into the oven, and overall deformation and local expansion or shrinkage. Sensitivity studies on generation of carbon dioxide, gravity, and shrinkage are presented to discuss their influences on bread geometry, porosity (reflecting the alveolar structure) and gas pressure. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3847–3863, 2016 相似文献
130.