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951.
  总被引:2,自引:0,他引:2  
ABSTRACT:  The influence of soybean-to-water ratio (1:6 and 1:8) and pH (6 and 7) on characteristics of soymilk treated by high pressure processing (HPP, 500 and 600 MPa, 10 min, 25 °C) or thermal treatment (95 °C for 30 min) was investigated. Changes in the soymilk appearance were observed only for the 1:6, pH 6 soymilk that underwent a sol formation after HPP treatment and was apparently more viscous after thermal treatment. These changes were reflected in the viscosity values of these soymilks, which were increased by a factor of 4.3 and 3.6, after HPP and thermal treatment, respectively. After HPP treatment at pH 7 at both 1:6 and 1:8 ratios, the viscosity of the soymilks was unchanged compared to the controls. HPP treatment significantly increased the emulsion stability for all soymilks tested except for the 1:6, pH 7 soymilk. Peptide profiles of thermal- and pressure-treated samples were not affected; however, aggregates were observed in the soluble protein fraction after thermal and pressure treatment. Surface free and total free sulfhydryl content, surface hydrophobicity, and solubility of the proteins were decreased after HPP and thermal treatment regardless the soybean-to-water ratios and pH values of the soymilk.  相似文献   
952.
    
Scope : The aim of this study was to determine the amounts of polyphenols and D ‐(?)‐quinic acid reaching the ileostomy bags of probands (and thus the colon in healthy humans) after ingestion of apple smoothie, a beverage containing 60% cloudy apple juice and 40% apple puree. Methods and results : Ten healthy ileostomy subjects each ingested 0.7 L of apple smoothie (a bottle). Their ileostomy bags were collected directly before and 1, 2, 4, 6 and 8 h after smoothie consumption, and the polyphenol and D ‐(?)‐quinic acid contents of the ileostomy fluids were examined using HPLC‐DAD and HPLC‐MS/MS. The total polyphenol and D ‐(?)‐quinic acid content of the apple smoothie was determined to be 1955.6±124.6 mg/0.7 L, which is very high compared to cloudy apple juices. The most abundant substances found in the ileostomy bags were oligomeric procyanidins (705.6±197.9 mg), D ‐(?)‐quinic acid (363.4±235.5 mg) and 5‐caffeoylquinic acid (76.7±26.8 mg). Overall recovery of ingested polyphenols and D ‐(?)‐quinic acid in the ileostomy bags was 63.3±16.1%. Conclusions: The amounts of polyphenol and D ‐(?)‐quinic acids reaching the ileostomy bags are considerably higher after apple smoothie consumption than after the consumption of cloudy apple juice or cider. These results suggest that the food matrix might affect the colonic availability of polyphenols, and apple smoothies could be more effective in the prevention of chronic colon diseases than both cloudy apple juice and apple cider.  相似文献   
953.
    
BACKGROUND: Egg phosvitin could be a good source of functional peptides. Enzymatic dephosphorylation and high‐pressure processing combined with thermal treatment applied before proteolysis could produce phosvitin hydrolysates with different properties compared to its native form. RESULTS: Phosvitin structure was maintained overall during high‐pressure treatment of 600 MPa applied at an initial temperature of 65 °C regardless of the pH and duration of treatment, confirming the high structural stability of this phosphoprotein. Treatment of phosvitin with phosphatase increased the degree of dephosphorylation from 24% to 63%, after 2 and 18 h, respectively. Moderate dephosphorylation of phosvitin prior to proteolytic digestion improved its hydrolysis, allowing formation of peptides with a molecular weight lower than 17,000 kDa as determined by size exclusion chromatography. Angiotensin‐converting enzyme (ACE) inhibition and antioxidant activity of dephosphorylated and protease‐treated phosvitin was increased by 52% and 39%, respectively, as compared to protease‐digested native phosvitin. CONCLUSION: Enzymatic dephosphorylation before proteolysis mimicking in vivo gut conditions improved ACE inhibition and antioxidant activity of phosvitin hydrolysates. Copyright © 2012 Society of Chemical Industry  相似文献   
954.
This study aimed to determine the effect of pretreating defatted soy flakes with ultrasound on soy protein isolate (SPI) yield and functionality. Defatted soy flakes dispersed into water (16%, w/w) were sonicated for 30, 60 and 120 s at ultrasonic amplitudes of 21 and 84 μmpp (peak to peak amplitude in μm), representing low and high power, respectively. The power densities were 0.30 and 2.56 W mL−1, respectively. The SPI yield increased by 13 and 34%, after sonication for 120 s at low and high power, respectively. The sonication of defatted soy flakes for 120 s at the higher power level improved the SPI solubility by 34% at pH 7.0, while decreasing emulsification and foaming capacities by 12 and 26%, respectively, when compared to control SPI. Rheological behavior of the SPI was also modified with significant loss in consistency coefficient due to sonication. Some of these results could be explained by the loss of the protein native state with increased sonication time and power.  相似文献   
955.
Composite materials are of interest because they can potentially combine the properties of their respective components in a manner that is useful for specific applications. Here, we report on the use of coffee as a low-cost, green reductant for the room temperature formation of catalytically active, supported metal nanoparticles. Specifically, we have leveraged the reduction potential of coffee in order to grow Pd and Ag nanoparticles at the surface of porous carbon microspheres synthesized via ultraspray pyrolysis. The metal nanoparticle-on-carbon microsphere composites were characterized using scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and thermal gravimetric analysis (TGA). To demonstrate the catalytic activity of Pd/C and Ag/C materials, Suzuki coupling reactions and nitroaromatic reduction reactions were employed, respectively.  相似文献   
956.
BACKGROUND: Electrical stimulation has been successfully employed to treat diseases involving electro-pathology in the heart, skeletal muscles, and the brain, but not in the GI tract. AIM: This study examined the clinical feasibility and efficacy of GES in treating patients with severe gastroparesis. METHODS: Nausea, vomiting, GEA, and liquid and solid gastric emptying were monitored in eleven patients with refractory gastroparesis at baseline and after one week of continuous electrical stimulation administered at 12 cycles/min. Eight patients were subsequently implanted with permanent stimulation devices. Follow-up studies were conducted after 1, 3, 6, and 12 mo. of stimulation. RESULTS: After one week of stimulation, patients' quantified symptoms of nausea and vomiting decreased significantly, and liquid emptying and GEA improved. This improvement was maintained over time in the patients who continued to receive stimulation. Emptying of solids showed progressive improvement that became significant after 3 mo. The three patients who did not receive stimulation after the trial period showed significantly higher symptoms at 12 mo. CONCLUSION: This paper demonstrates that GES at a frequency of 12 cycles/min has an immediate antiemetic effect, followed by an improvement in disordered gastric emptying.  相似文献   
957.
Pigmented UV radiation-curable coatings have been a challenge to the coatings formulator for a long time. A critical match of pigment and photoinitiator package is crucial, for good cure. Another issue facing the coatings chemist is the popularity of low energy lamps, which offer ease of handling, reduced safety concerns, and a low price tag. Obviously, the combination of curing pigmented coatings and using low energy lamps poses a special challenge. To improve the pigmented coating development cycle, a rapid workflow was needed to screen formulations for cure under low energy UV-A radiation. For these types of applications, a high-throughput, screening assay for discovering desirable photoinitiator packages was developed. Fluorescent dye-doped coatings cured under UV-A radiation were extracted with solvent. The relative degree-of-cure, of the film was determined to be inversely related to a combination of the absorbance and fluorescence of the extractant. When this assay is used in conjunction with automated liquid handling and a spectrophotometer with an x-y scanning stage, the coatings formulator can analyze a large variable set in a short period of time. A primary screening of photoinitiators using this workflow suggests Lucirin® TPO-L, Darocur® 4265, and Irgacure® 2100 as optimum choices.  相似文献   
958.
Recent laser upgrades on the Hot Helicon Experiment at West Virginia University have enabled multiplexed simultaneous measurements of the ion velocity distribution function at a single location, expanding our capabilities in laser-induced fluorescence diagnostics. The laser output is split into two beams, each modulated with an optical chopper and injected perpendicular and parallel to the magnetic field. Light from the crossing point of the beams is transported to a narrow-band photomultiplier tube filtered at the fluorescence wavelength and monitored by two lock-in amplifiers, each referenced to one of the two chopper frequencies.  相似文献   
959.
Tests of addiction treatments seldom reveal where treatment exercises its effect (i.e., promoting initial abstinence, preventing lapses, and/or impeding progression from lapse to relapse). The authors illustrate analyses distinguishing effects on these milestones in a randomized trial of high-dose nicotine patch (35 mg; n = 188) versus placebo (n = 136) in adult smokers, who used electronic diaries to monitor smoking in real time during 5 weeks of treatment. High-dose patch promoted initial abstinence (hazard ratio [HR] = 1.3) and decreased the risk of lapsing among those who achieved abstinence (HR = 1.6). The biggest effect of treatment was to prevent progression to relapse among those who had lapsed (HR = 7.1). Analysis of effects by milestones may enhance understanding of cessation treatments and their mechanisms of action. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
960.

Background

The present study sought to determine whether the consumption of a mineral-rich alkalizing (AK) bottled water could improve both acid-base balance and hydration status in young healthy adults under free-living conditions. The AK water contains a naturally high mineral content along with Alka-PlexLiquid, a dissolved supplement that increases the mineral content and gives the water an alkalizing pH of 10.0.

Methods

Thirty-eight subjects were matched by gender and self-reported physical activity (SRPA, hrs/week) and then split into Control (12 women, 7 men; Mean +/- SD: 23 +/- 2 yrs; 7.2 +/- 3.6 hrs/week SRPA) and Experimental (13 women, 6 men; 22 +/- 2 yrs; 6.4 +/- 4.0 hrs/week SRPA) groups. The Control group consumed non-mineralized placebo bottled water over a 4-week period while the Experimental group consumed the placebo water during the 1st and 4th weeks and the AK water during the middle 2-week treatment period. Fingertip blood and 24-hour urine samples were collected three times each week for subsequent measures of blood and urine osmolality and pH, as well as total urine volume. Dependent variables were analyzed using multivariate repeated measures ANOVA with post-hoc focused on evaluating changes over time within Control and Experimental groups (alpha = 0.05).

Results

There were no significant changes in any of the dependent variables for the Control group. The Experimental group, however, showed significant increases in both the blood and urine pH (6.23 to 7.07 and 7.52 to 7.69, respectively), a decreased blood and increased urine osmolality, and a decreased urine output (2.51 to 2.05 L/day), all during the second week of the treatment period (P < 0.05). Further, these changes reversed for the Experimental group once subjects switched to the placebo water during the 4th week.

Conclusions

Consumption of AK water was associated with improved acid-base balance (i.e., an alkalization of the blood and urine) and hydration status when consumed under free-living conditions. In contrast, subjects who consumed the placebo bottled water showed no changes over the same period of time. These results indicate that the habitual consumption of AK water may be a valuable nutritional vector for influencing both acid-base balance and hydration status in healthy adults.  相似文献   
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