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Food Science and Biotechnology - Wheat germ shows the highest nutritional value of the kernel. It is highly susceptible to rancidity due to high content of unsaturated fat and presence of oxidative...  相似文献   
73.
The Journal of Supercomputing - Multibody systems consist of a set of components connected through some joints, where the movement of the system is determined by those of its components. Their...  相似文献   
74.
The present research introduces a new mechanism by which emotion can affect evaluation. On the basis of the self-validation hypothesis (R. E. Petty, P. Bri?ol, & Z. L. Tormala, see record 2002-12575-003), the authors predicted and found that emotion can influence evaluative judgments by affecting the confidence people have in their thoughts to a persuasive message. In each study, participants first read a strong or weak persuasive communication. After listing their thoughts about the message, participants were induced to feel happy or sad. Relative to sad participants, those put in a happy state reported more thought confidence. As a consequence, the effect of argument quality on attitudes was greater for happy than for sad participants. These self-validation effects generalized across different emotion inductions, different persuasion topics, and different measures of thought confidence. In one study, happy and sad conditions each differed from a neutral affect control. Most important, these metacognitive effects of emotion only occurred under high elaboration conditions. In contrast, individuals with relatively low motivation to think showed a main effect of emotion on attitudes, regardless of argument quality. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.
Fibrosis is the strongest predictor for disease-specific mortality in non-alcoholic fatty liver diseases (NAFLD), but the need for liver biopsy limits its diagnosis. We assessed the performance of plasma ficolin-2 (FCN-2) as a biomarker of fibrosis identified by an in silico discovery strategy. Two hundred and thirty-five morbidly obese (MO) subjects with biopsy-proven NAFLD stratified by fibrosis stage (F0, n = 44; F1, n = 134; F2, n = 46; F3/F4, n = 11) and 40 cirrhotic patients were enrolled. The cohort was subdivided into discovery (n = 76) and validation groups (n = 159). The plasma level of FCN-2 and other candidate markers was determined. FCN-2 was inversely correlated with the stage of liver fibrosis (ρ = −0.49, p < 0.001) independently of steatosis (p = 0.90), inflammation (p = 0.57), and ballooning (p = 0.59). In the global cohort, FCN-2 level decreased significantly in a stepwise fashion from F0/F1 (median 4753 ng/mL) to F2–F3–F4 (2760 ng/mL) and in cirrhotic subjects (1418 ng/mL). The diagnostic performance of FCN-2 in detecting F ≥ 2 was higher than other indexes (APRI, FIB-4) (AUROC 0.82, 0.68, and 0.6, respectively). The accuracy improved when combined with APRI score and HDL values (FCNscore, AUROC 0.85). Overall, the FCN-2 plasma level can accurately discriminate liver fibrosis status (minimal vs. moderate/advanced) significantly improving the fibrosis diagnostic algorithms.  相似文献   
76.
Different high impact polystyrenes were synthesized using styrene/butadiene copolymers (SB) with PS/PB composition: 30/70 and 20/80 as the precursor rubber, benzoyl peroxide (BPO) as the initiator, and ter‐dodecyl mercaptane (TDM) as the chain transfer agent. During the polymerization, several samples were taken and analyzed under different techniques to evaluate the phase inversion (PI) phenomenon. The PI was determined through transmission electron microscopy (TEM) and through dynamic oscillatory behavior, where the PI takes places when the relaxation process presents the lower value of activation energy. Finally, the Choi and Schowalter emulsion model was employed to elucidate the PI, and relevant information was revealed about the interfacial tension in the PI. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers  相似文献   
77.
Diarrhea caused by enterotoxigenic Escherichia coli (ETEC) is the main infectious disease of newborn calves. The first step of infection involves bacterial attachment to the intestinal mucosa. This adhesion is mediated by fimbriae that recognize some glycoconjugates on the host cell surface, in particular, several gangliosides. Because milk also contains gangliosides, these have been suggested to serve as ligands for bacterial fimbriae and thus prevent the bacterial attachment to mucosa. The most relevant ETEC strains in calves, including those with K99 and F41 fimbriae, were assayed to determine whether they are able to bind gangliosides isolated from several stages of bovine lactation. Both GM3 and GD3, the main gangliosides of milk, were recognized by ETEC strains, although the different fimbriae showed diverse levels of affinity. Unexpectedly, the adhesion to colostral gangliosides was considerably weaker than that to gangliosides from the other stages of lactation. Because the carbohydrate moiety did not change and because differences in the percentages of unsaturated FA and sphingosine between colostrum and other stages were observed, we conclude that the differences in adhesion could be due to a different composition of the ganglioside caramide.  相似文献   
78.
BACKGROUND: Microorganisms have often been considered for the production of oils and fats as an alternative to agricultural and animal resources. Extraction experiments were performed using a strain of the yeast Yarrowia lipolytica (Y. lipolytica), a high‐lipid‐content yeast. Three different methods were tested: Soxhlet extraction, accelerated solvent extraction (ASE) and supercritical carbon dioxide (SCCO2) extraction using ethanol as a co‐solvent. Also, high pressure solubility measurements in the systems ‘CO2 + yeast oil’ and ‘CO2 + ethanol + yeast oil’ were carried out. RESULTS: The solubility experiments determined that, at the conditions of the supercritical extractor (40 °C and 20 MPa), a maximum concentration of 10 mg of yeast oil per g of solvent can be expected in pure CO2. 10% w/w of ethanol in the solvent mixture increased this value to almost 15 mg of yeast oil per g of solvent. Different pretreatments were necessary to obtain satisfactory yields in the extraction experiments. The Soxhlet and the ASE method were not able to complete the lipid extraction. The ‘SCCO2 + ethanol’ extraction curves revealed the influence of the different pretreatments on the extraction mechanism. CONCLUSION: Evaluating the effectiveness of a given pretreatment, ASE reduced the amount of material and solvent used compared with Soxhlet. In all three cases, the best total extraction performance was obtained for the ethanol‐macerated yeast (EtM). Addition of ethanol to the solvent mixture enhanced the oil solubility. Oil can be extracted from Y. lipolytica in two different steps: a non‐selective ethanol extraction followed by TAG‐selective SCCO2 purification. © 2012 Society of Chemical Industry  相似文献   
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Direct interfacial molecular dynamics simulations are used to obtain the phase behavior and interfacial tension of CO2–H2O–NaCl mixtures over a broad temperature and pressure range (50°C ≤ T ≤ 250°C, 0 ≤ P ≤ 600 bar) and NaCl concentrations (1–4 mol/kg H2O). The predictive ability of several existing water (SPC and TIP4P2005), carbon dioxide (EPM2 and TraPPE), and sodium chloride (SD and DRVH) models is studied and compared, using conventional Lorentz–Berthelot combining rules for the unlike‐pair parameters. Under conditions of moderate NaCl molality (~1 mol/kg H2O), the predictions of the CO2 solubility in the water‐rich and CO2‐rich phase resemble those in the CO2–H2O system [Liu et al., J Phys Chem B. 2011;115:6629–6635]. Consistent with our previous work, the TraPPE/TIP4P2005 model combination gives the best overall performance in predicting coexistence composition and pressure in the water‐rich phase. Critical assessments are also made on the ranges of temperature and pressure where particular model combinations work better. The dependence of the interfacial tension on temperature and pressure is better predicted by the TraPPE/TIP4P2005 and EPM2/SPC models, whereas the EPM2/TIP4P2005 model overestimates this property by 10–20%, possibly due to the inadequacy of the combining rules. It is also found that the interfacial tension increases with salt concentration, consistent with experimental observations. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3514–3522, 2013  相似文献   
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