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Introduction: Staphylococcal infection of endogenous origin is an important cause of morbidity and mortality in patients who receive hemodialysis (HD). The risk of such infections in nasal carriers of the organism is well defined. Extranasal carriage of the organism at extranasal sites may pose similar risks. Methods: A total of 70 patients about to undergo internal jugular vein catheterization for HD were enrolled in this prospective observational study. Swab cultures were obtained from anterior nares, posterior pharynx, axillae, toe web spaces, and vascular access sites at baseline and 1 week later. A patient was defined as a persistent carrier when the same organism was grown in both samples. Staphylococcus aureus bloodstream infections were assessed by blood and catheter tip cultures over a 90‐day period. Findings: The mean age of the patients was 43.71 ± 16.2 years. Persistent S. aureus carriage at anterior nares, throat, axilla, toe web spaces, vascular access site, and all sites was documented in 27.9%, 11.4%, 40%, 32.9%, 4.3%, and 64.2% of patients, respectively. Fifteen patients developed S. aureus infections. Catheter related S. aureus infections (CRI) were more likely in persistent carriers than nonpersistent carriers with odds ratios (95% CI) of 10.2 (2.8–37.1), 8.6 (1.7–42.2), 17.3 (3.4–86.0), 3.0 (0.9–9.8), and 1.9 (0.2–22.4) for anterior nares, throat, axilla, toe web spaces, and vascular access site carriers, respectively. The probability of developing CRI in persistent S. aureus carriers was 55% compared to none in noncarriers at 90 days (P = 0.04). Discussion: Extranasal S. aureus carriage is as significant a risk factor as nasal carriage for staphylococcal infections in patients on HD through catheters. The study is limited by lack of molecular phenotyping.  相似文献   
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Starch isolated from maranta (Maranta arundinacea) tuber and studied for its various physicochemical characteristics. The amylose content of the starch was 24.8%. SEM showed that the granules were small indented and spherical. Maranta starch granule size has a range of 2.92–6.42 μm, (mean of 4.84 μm), length/degree of 1.20, and roundness of 0.73. Maranta starch has a gelatinization temperature of 74.8°C, peak viscosity of 498 BU, and cold paste viscosity of 669 BU. It also possessed higher freeze-thaw stability. Dynamic rheological properties of maranta starch, measured using parallel plate geometry showed increased storage modulus (G’) values, while loss modulus (G″) values were decreased with increasing frequency values (0–100 Hz). The low gelatinization temperature and high freeze thaw stability of starch indicates its potential for application as a thickener in food industries.  相似文献   
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Decaffeination of food and beverage products is in high demand. In this study, a caffeine-degrading bacterium Burkholderia spp. was isolated from coffee plantation area of Chiang Mai province of Thailand. The bacterial isolates were first identified by morphological, physiological, and biochemical tests followed by 16S rDNA analysis. The bacterial isolate of Burkholderia spp. showed 45.5% of caffeine degradation in caffeine containing media (2.5 g/L) after 110 h of incubation period. Burkholderia spp. showed only 2.6% caffeine degradation when exposed to high concentrations of caffeine containing medium (20 g/L). The growth rate of Burkholderia spp. declined with the increase in the caffeine concentration, which indicated the inhibiting effect of caffeine at very high concentrations. The maximum growth rate of 0.053 h?1 was observed at 2.5 g/L of caffeine. Overall due to high caffeine tolerance and biodegradation of caffeine, Burkholderia spp. can be effectively used to degrade caffeine from agro-industrial wastes targeted for value added food applications and environmental remediation.  相似文献   
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Multiferroic composites of spinel ferrite and ferroelectric xCoFe2O4 – (1-x)Na0.5Bi0.5TiO3 (with x = 0.10,0.30,0.50) were efficiently prepared by standard solid state reaction mechanism. X-ray diffractometer was used to analyze crystal structure of the prepared composites. The observed XRD patterns of the composites comprise peaks of both the phases i.e. ferrite and ferroelectric, with no sign of secondary peaks. Rietveld refinement of XRD data further confirms the coexistence of these two phases with cubic (Fd3m) and rhombohedral (R3c) symmetry corresponding to ferrite and ferroelectric phase respectively. The 3-dimensional overview of crystal structure of pure CoFe2O4 and Na0.5Bi0.5TiO3 and of composite 0.50CoFe2O4?0.50Na0.5Bi0.5TiO3 is generated by using refined parameters. The dielectric constant (ε´) and dielectric loss (tanδ) values were recorded as a function of frequency ranging from 100?Hz to 7?MHz and at different temperatures. Both ε´ and tanδ follow dispersion pattern at lower frequencies while show frequency independent behavior at higher frequencies. The magnetic evaluation carried by analyzing M-H hysteresis loop reveals the ferrimagnetic characteristics of these composites. The highest value of magnetic moment is 1.12μB observed for composite 0.50CoFe2O4 – 0.50Na0.5Bi0.5TiO3. Magnetoelectric (ME) voltage coefficient (α) was also demonstrated to observe the interaction between ferrite and ferroelectric phases. The highest value of α (72.72μV/Oe cm) is obtained for low ferrite composition 0.10CoFe2O4 – 0.90Na0.5Bi0.5TiO3, which suggests the dependence of magnetoelectric response on the resistivity of the composites.  相似文献   
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O‐aminophenol was reacted with glutraldehyde to obtain Schiff base, which was then reacted with formaldehyde in slight acidic medium to generate phenolic groups. Now the substituted Schiff base was reacted with the transition metal acetates of Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) to get polymeric metal complexes. Their structures have been elucidated on the basis of elemental analyses, 1H NMR spectra, 13C NMR spectra, magnetic measurements, thermogravimetric analyses, electronic spectra, and infrared spectra. The results are in accordance with an octahedral environment around the central metal ion. The polychelates of Mn(II), Co(II), Ni(II), and Cu(II) are paramagnetic while Zn(II) polychelate was found to be diamagnetic. The synthesized Schiff base acted as a uninegative bidentate ligand and bonding occurs through the hydroxyl oxygen and nitrogen atoms. The thermal behavior of these coordinating polymers was studied by TGA in nitrogen atmosphere up to the temperature range of 800°C. All the synthesized polychelates were also screened for their biocidal activity against Escherichia coli, Staphylococcus aureus, Bacillus subtilis (bacteria), Candida albicans, and Muller species (yeast) by using agar well diffusion method. All the metal polychelates show promising antimicrobial activities. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci 124:3971–3979, 2012  相似文献   
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The two parameters of services output of water utilities are the per capita water available for consumption and the hours for which water is supplied per day. However, water utilities in India differ on the level of these outputs substantially. This paper uses the data for water utilities in 31 cities to analyse their performance in delivery of services. Using data envelopment analysis, a measure of technical efficiency for various utilities is calculated. The results indicate that water utilities can increase the delivery of water on a per capita basis and increase the hours of supply per day by about 18%. Nearly 37% of the increase in services could result from changing the scale of operation. This paper also discusses if the institutional framework within which these utilities operate has implications on their efficiency.  相似文献   
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Successful food hygiene training and the consent of safe food handling practices learnt during training are critical elements in the control of food-borne illnesses throughout the world. It is true for food handlers and vendors belonging to all sectors. But, it is all the more urgent for street vendors because they are more exposed to environmental hazards and are predominantly from much weaker socio-economic backgrounds and yet cater to the general mass. Using a cross-sectional study design a sample of 80 street food vendors were selected and provided with training to evaluate the existing Knowledge, Attitude and Practice (KAP) regarding food safety and hygiene and the change of the same after training interventions. Responses regarding KAP on food safety and hygiene before and after training revealed that there was a significant change in their perception to food safety knowledge and also practices. The knowledge level of the food vendors increased from an average 24.35%–66.2% after training interventions. The overall performance rating of full adoption of good hygiene practices by the vendors ranged from 37.5% to 50.8% in post-training period.  相似文献   
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The demand of low power high density integrated circuits is increasing in modern battery operated portable systems. Sub-threshold region of MOS transistors is the most desirable region for energy efficient circuit design. The operating ultra-low power supply voltage is the key design constraint with accurate output performance in sub-threshold region. Degrading of the performance metrics in Static random access memory (SRAM) cell with process variation effects are of major concern in sub-threshold region. In this paper, a bootstrapped driver circuit and a bootstrapped driver dynamic body biasing technique is proposed to assist write operation which improves the write-ability of sub-threshold 8T-SRAM cell under process variations. The bootstrapped driver circuit minimizes the write delay of SRAM cell. The bootstrapped driver dynamic body bias increases the output voltage levels by boosting factor therefore increasing in switching threshold voltage of MOS devices during hold and read operation of SRAM latch. The increment in threshold voltage improves the static noise margin and minimizing the process variation effects. Monte-Carlo simulation results with 3 \(\sigma \) Gaussian distributions show the improvements in write delay by 11.25 %, read SNM by 12.20 % and write SNM by 12.57 % in 8T-SRAM cell under process variations at 32 nm bulk CMOS process technology node.  相似文献   
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