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排序方式: 共有95条查询结果,搜索用时 15 毫秒
1.
Bacterial strain of Rhodococcus sp. (JUBT1) isolated from petrol/diesel station has been used for the desulfurization of different model organo-sulfur compounds like DBT, substituted DBT, etc. which are difficult to remove in the conventional hydro-desulfurization of diesel fraction. The initial concentration of organo-sulfur compounds has been varied in the range of 100–1000 mg/dm3. Under the present experimental range, the bacterial growth has been observed to follow Haldane-type kinetics characterizing the presence of substrate inhibition. The extent of inhibition by the substrate has been observed to increase with the number of substituents in the same range of initial concentration of different organo-sulfur compounds. The values of intrinsic kinetic parameters, like maximum desulfurization rate, vmax, half saturation constant, KS, inhibition constant, KSi and the maximum substrate concentration, CSmax, corresponding to the maximum uninhibited rate of desulfurization, have been determined using each organo-sulfur compound having different number of substituents as limiting substrate. Relative changes in the values of the kinetic parameters have been correlated to the number of substitutions. Separate studies have also been conducted to determine the kinetics of bio-desulfurization of a hydro-treated diesel fraction. The concentration of sulfur in diesel was selected in the range of 100–500 mg/dm3.

The effect of aqueous to non-aqueous ratio on the rate of specific desulfurization of hydro-treated diesel fraction in the range from 1:9 to 9:1 has also been studied in the present investigation. Mathematical models have been developed to predict the conversion of sulfur during batch-type bio-desulfurization of model compounds as well as diesel having known distribution of organo-sulfur compounds. The predictions of the model satisfactorily compare with the experimental results.  相似文献   

2.
Using half-leaf method O,O'-diisopropyl (3-(L-1-(benzylamino)-1-oxo-3- phenylpropan-2-yl)thioureido)(phenyl)methyl phosphonate (2009104) was studied for its activity on tobacco mosaic virus (TMV). It showed good curative activity in vivo and the curative activity at 500 μg/mL was found to be 53.3%. In vivo treatment with the control agent Ningnanmycin at 500 μg/mL resulted in 51.2% inhibition and curative inhibition rates respectively. Dot-ELISA test was employed to verify the efficacy of activity of compound 200910 for anti-TMV activity. The mechanism of action of compound 2009104 to resist TMV was also studied. The results showed that the resistance enzymes PAL, POD, SOD activity and chlorophyll content after TMV inoculation K(326) (Nicotiana tabacum K(326)) of tobacco plants followed by treatment with compound 2009104 were significantly enhanced. The study of the effect of compound 2009104 on TMV capsid protein (CP) showed that it inhibited the polymerization process of TMV-CP in vitro.  相似文献   
3.
The preparation and regeneration conditions of the identified catalyst X/Y/MgO/γ-Al2O3 with high catalytic activity were studied and optimized. The biodiesel was prepared by transesterification of Jatropha curcas seed oil produced in Guizhou with methanol at its reflux temoerature in the presence of X/Y/MgO/γ-Al2O3. The pilot plant tests were carried out in a 100 L reaction vessel. Both average yield and fatty acid methyl esters (FAME) content reached more than 96.50% under the optimum reaction conditions of the pilot plant tests designed withan oil/methanol molar ratio of 1: 10, catalyst concentration of 1.00%, and reaction time of 3 h at reflux temperature. In addition, analysis shows that the quality of biodiesel meets the standard EN 14214. __________ Translated from Modern Chemical Industry, 2007, 27(Suppl. 2): 452–455 [译自: 现代化工]  相似文献   
4.
When a stack consisting of layers of soft elastomer and thin metallic film is subjected to low intensity impact by releasing an axisymmetric spherical indenter from a vertical height, the foils buried within the stack undergoes large deformation and fracture. The shape of the deformed area nevertheless remains circular, its radius first increases with the depth from the surface of the stack and then decreases. In contrast, here we show that the symmetry of the deformed area breaks down when instead of a smooth elastomeric layer, one with topographical patterns is used in the stack. The metallic foil deforms through a polygonal area. The size and shape of the polygonal area vary with the flexibility of foil, geometry and dimension of the patterns and the intensity of the impact. For example, for one elastomeric layer decorated with pillars arranged in a square array, the damaged area turns rectangular to hexagonal and then to octagonal with increasing severity of impact, very much similar to polygonal wetting and spreading by a liquid on a patterned substrate.  相似文献   
5.
Negative Bias Temperature Instability (NBTI) in p-MOSFETs is a serious reliability concern for digital and analog CMOS circuit applications. Strain in the channel region affects negative bias temperature instabilities, low frequency noise, radiation hardness, gate oxide quality and hot carrier performance. The understanding of these phenomena in strain-engineered p-MOSFETs from fundamental physics is essential. In this paper, technology CAD (TCAD) has been used to study the effects of strain on the negative bias temperature instabilities in p-MOSFETs. A quasi two dimensional (quasi-2D) physics-based Coulomb scattering mobility model for strained-Si has been developed and implemented in Synopsys Sentaurus Device tool for device simulation to understand NBTI in strain-engineered p-MOSFETs.  相似文献   
6.
In this paper, we define generalised fuzzy soft sets and study some of their properties. Application of generalised fuzzy soft sets in decision making problem and medical diagnosis problem has been shown.  相似文献   
7.
Carbon–copper composites with varying copper to carbon ratio of 0.66–1.5 (by weight) were developed from coal-tar-pitch-derived green coke (as such or modified with natural graphite) as carbon source and electrolytic grade copper powder at different heat treatment temperatures (HTTs) of 1000–1400 °C. The physical, mechanical, and electrical properties differ depending upon the HTT and also on copper to carbon ratio (Cu/C). The composites prepared at HTT of 1100 °C having Cu/C ratio of 0.66 and 0.9 exhibited a high bending strength of 150 and 140 MPa, bulk density of 2.63 and 2.81 gm/cm3, electrical resistivity of 1.6 and 0.96 m Ω cm and shore hardness of 88 and 84, respectively, in spite of well-known inadequate wettability between copper and carbon. Increasing the temperature from 1100 °C for processing of the composites deteriorated the properties mainly due to the loss of copper through melting above 1100 °C as revealed by X-ray, scanning electron microscopy, thermal analysis and EDAX studies.  相似文献   
8.
Virtual microstructures having a systematic variation of amount, mean size, standard deviation of size, and spatial arrangement of intermetallics have been synthesized, and their deformation behavior in uniaxial tension has been evaluated using finite element analysis. Four spatial arrangements of intermetallics have been considered in this work, namely: random, clustered, and two-ordered structures. Various mathematical quantities have been developed to quantify the severity of deformation including plastic work density distribution (PWDD), percentile work-density volume criterion (PWC), and percentile stress volume criterion (PSC). This approach eliminates the need for an external trigger in FEA to achieve localization. The method developed has led to a better understanding of the effect of different microstructural attributes on the process of deformation. This has resulted in guidelines for optimizing the microstructure to minimize material damage and thereby maximize ductility.  相似文献   
9.
Heteroglycan and xyloglucan rich fractions were extracted from Indian samples of Enteromorpha compressa in 25% yield by sequential extractions with water and alkali. This heteroglycan is sulfated and has an apparent molecular mass of 55 kDa. Chemical structural analysis of this polysaccharide revealed a branched structure having 1,4- and 1,2,4-linked rhamnose 3-sulphate, 1,4-linked glucose, 1,3- and 1,6- linked galactose, 1,4- and terminally linked glucuronic acid and 1,4-linked xylose partially sulfated on O-2. Chemical and spectroscopic analysis showed that the 4-M KOH extracted hemicellulosic fraction contained an unusual β-(1,4)-linked linear xyloglucan. Enzyme hydrolysis and analysis of the resulting fragments by matrix-assisted laser desorption ionization-time of flight-mass spectrometry (MALDI-TOF-MS) showed that this linear polymer contained partially sulfated Glc3Xyl2 or Glc4Xyl2 as oligomeric building subunits.  相似文献   
10.
Pattern Analysis and Applications - Outlier detection approaches show their efficacy while extracting unforeseen knowledge in domains such as intrusion detection, e-commerce, and fraudulent...  相似文献   
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