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101.
In this study, the effect of different sonication times (10, 20, and 30 min) on oil yields, extracted by using soxhlet together with preultrasonic treatment, and fatty acid composition of seed/kernels were investigated. The sonication of samples for 30 min caused the highest increase in oil yield of hazelnut (from 62.38 to 63.60%) and black cumin (from 27.90 to 31.80%) (p < .05). The appropriate sonication time for oil yield of peanut was 10 min, with the range of 51.50%. After sonication process, the dominant fatty acid contents of all samples showed a change and the major decrease in oleic acid amount of hazelnut (from 75.20 to 74.27%) and peanut oils (from 57.10 to 56.69%) and linoleic acid content of black cumin (from 58.38 to 57.50%) were determined when samples sonicated for 30 min (p < .05). Sonication process caused a decreasing in black cumin oil, and the reduction increased with sonication time.

Practical applications

Ultrasound‐assisted extraction method can be used as an alternative extraction method for conventional extraction. Ultrasonic‐assisted extraction has some advantages as being efficiency, speed and using low temperatures, which prevents thermal damage. The ultrasound process enables to greater influence of solvent into the sample matrix and increases mass transfer. Thereby, the higher extract yield, almost 23%, provided with ultrasonic‐assisted extraction in comparison to soxhlet extraction.  相似文献   
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Possible interactions between inflammatory and nutritional markers and their impact on recombinant human erythropoietin (rHuEPO) hyporesponsiveness are not well understood. We investigated the role of nutritional status in rHuEPO requirement in maintenance hemodialysis (MHD) patients without evidence of inflammation. This cross-sectional study included 88 MHD patients. The associations between required rHuEPO dose and malnutrition-inflammation score (MIS) and several laboratory values known to be related to nutrition and/or inflammation were analyzed. Anthropometric measures including body mass index, triceps skinfold thickness, and midarm circumferences were also measured. Twenty-three patients with serum C-reactive protein levels >10 mg/L were excluded from the analysis. The remaining 65 patients (male/female, 41/24; age 49.1+/-11.4 years; dialysis duration 99.7+/-63.0 months) were studied. These patients had moderate malnutrition and the average MIS was 7.4 (range 3-17). The average weekly dose of administered rHuEPO was 69.1+/-63.1 U/kg. Malnutrition-inflammation score had a positive correlation with the serum concentration of tumor necrosis factor-alpha, whereas it had a negative correlation with anthropometric measures, total iron-binding capacity, prealbumin, phosphorus, creatinine, and triglyceride. According to Pearson's correlation analysis, significant relationships of increased MIS with increased required rHuEPO dose and rHuEPO responsiveness index (EPO divided by hematocrit) were observed (p=0.008, r=-0.326; p=0.017, r=-0.306, respectively). Recombinant human erythropoietin dose requirement is correlated with MIS and adverse nutritional status in MHD patients without evidence of inflammation. Further research should focus on reversing the undergoing microinflammation for a better outcome in dialysis patients.  相似文献   
104.
This study examined the pressurized solvent extraction of wheat germ oil. The effects of temperature (45–135 °C at 1500 psi), extraction time, sample size and solvent type on the extraction efficiency and oil quality were studied. Extraction efficiency of the normal-hexane was compared to that of the iso- and high purity-hexane, iso-propanol, ethanol and acetone. The extracts were analyzed for n-3 and n-6 polyunsaturated fatty acid content. Pressurized solvent extraction reduced extraction time significantly as compared to Soxhlet extraction. The time required for complete oil recovery was dependent on the amount of wheat germ used for extraction. The amount of extract collected was highest when ethanol was used as a solvent for pressurized solvent extraction. Soxhlet and pressurized solvent extractions resulted in similar oil yields when hexane was used as a solvent. Fatty acid composition of the extracts was not affected by either temperature or extraction method. The experimental results indicate that a pressurized solvent extraction technique reduces solvent consumption and extraction time with no adverse effect on the extraction yield and fatty acid composition of the oil.  相似文献   
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The presence of zinc oxide in rubber compounds is tried to be minimized due to environmental concerns. In this study; the effect of different zinc oxide types on ageing properties of SBR compounds was investigated. Active zinc oxide and zinc oxide coat on CaCO3 core were used in SBR compounds and their ageing characteristics were compared. The changes in tensile properties, hardness and rebound resilience were followed and evaluated.  相似文献   
108.
In this study enzymatic extraction of oil from wheat germ (WG) was investigated. Four enzymes (Viscozyme L, Multifect CX 13L, Multifect CX GC and Alcalase 2.4L FG) were screened for their efficacy to release oil from WG. Alcalase 2.4L FG treatment of WG improved oil extraction yield as compared to a control (aqueous extraction without enzyme). Alcalase 2.4L FG, which resulted in significantly higher oil yield than the other three enzymes, was chosen for optimization of the enzymatic oil extraction process by using Response Surface Methodology (RSM). Three processing parameters, liquid/solid ratio, extraction time and enzyme concentration, were investigated as the independent variables. Based on the experimental results, the highest oil yield, 66.5% (w/w), was obtained under the following conditions; liquid/solid ratio 16.5, enzyme concentration 1.1% and extraction time 19.25 h. A cubic model with R 2 of 0.91 was developed to describe the enzymatic extraction process. Although the cubic model predicted WG oil extraction yields well within the processing conditions studied in this study it was not effective beyond the experimental range. Further research focusing on high liquid/solid ratio, 16–20, and extraction time in 18–24 h and 0.5–5 h ranges is necessary to improve the model developed in this study.  相似文献   
109.
A series of new bis triazole Schiff base derivatives (4) were prepared in good yields by treatment of 4‐amino‐3,5‐diphenyl‐4H‐1,2,4‐triazole (3) with bisaldehydes (1). Schiff bases (4) were reduced with NaBH4 to afford the corresponding bisaminotriazoles (5). All the new compounds were characterized by IR, 1H NMR and 13C NMR spectral data. Their overall extraction (log Kex) constants for 1 : 1 (M : L) complexes and CHCl3/H2O systems were determined at 25 ± 0.1°C to investigate the relationship between structure and selectivity toward various metal cations. The extraction equilibrium constants were estimated using CHCl3/H2O membrane transfer with inductively coupled plasma‐atomic emission spectroscopy spectroscopy. The stability sequence of the triazole derivatives in CHCl3 for the metal cations was exhibited a characteristic preference order of extractability to metal ions [Fe(III) > Cu(II) > Pb(II) > Co(II) > Ni(II) > Mn(II) > Zn(II) > Mg(II) > Ca(II)]. The compounds were tested for anti‐microbial activity applying agar diffusion technique for 11 bacteria. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   
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