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101.
Two polyol surfactants ((a) a crude product of 60% monoglyceride content and (b) a homogeneous sorbitan ester) have been prepared by alcoholysis from the not well known edible Moringa concanensis seed oil. These products constituted mainly oleic acid, which will be suitable for utilisation in the pharmaceutical industry. The optimum conditions of glycerolysis of the moringa seed oil have also been found.  相似文献   
102.
The fatty acid composition of the seed oils of the species, Hydnocarpus kurzii, H. wightiana and H. odorata were determined by gas-liquid chromatographic (g.l.c.) analysis. The percentages of individual fatty acids were found to be: hydnocarpic 23.0, 33.9, -; chaulmoogric 29.6, 35.0, -; gorlic 25.1, 12.8, -; lower cyclic homologues 0.3, 4.6, -; myristic 0.6, 0.8, 0.4; palmitic 8.4, 5.6, 11.8; stearic -, 0.6, 4.7; palmitoleic 6.0, 1.3, 0.5; oleic 5.4, 3.6, 21.8; linoleic 1.6, 1.8, 29.3; linolenic -, -, 31.2; respectively.  相似文献   
103.
A nutritional study was carried out with white albino rats fed treated and untreated sal meal at 30% level in diet for 3 months. The effect of high protein level in diet on rats fed 30% untreated sal meal was also investigated. rats fed 30% sal meal with intact tannin showed abnormal lipid spectrum and also protein content in both liver and serum while the lipid spectrum and protein content in liver and serum of rats fed 30% treated sal meal were comparable to that of control rats. The toxic effect of sal meal was reduced to some extent when the protein level was improved in diet.  相似文献   
104.
Psychro-active bacteria, important constituents of polar ecosystems, have a unique ability to remain active at temperatures below 0 degrees C, yet it is not known to what extent the composition of their outer cell surfaces aids in their low-temperature viability. In this study, aqueous suspensions of five strains of Arctic psychro-active marine bacteria (PAMB) (mostly sea-ice isolates), were characterized by surface-enhanced Raman spectroscopy (SERS) and compared with SERS spectra from E. coli and P. aerigunosa. We find the SERS spectra of the five psychro-active bacterial strains are similar within experimental reproducibility. However, these spectra are significantly different from the spectra of P. aeruginosa and E. coli. We find that the relative intensities of many of the common peaks show the largest differences reported so far for bacterial samples. An indication of a peak was found in the PAMB spectra that has been identified as characteristic of unsaturated fatty acids and suggests that the outer membranes of the PAMB may contain unsaturated fatty acids. We find that using suspensions of silver colloid particles greatly intensifies the Raman peaks and quenches the fluorescence from bacterial samples. This technique is useful for examination of specific biochemical differences among bacteria.  相似文献   
105.
The conditions leading to the Donnan membrane equilibrium arise from the inability of ions to diffuse out from one phase in a heterogeneous system. In a polymeric cation exchanger, negatively charged sulfonic acid groups are covalently attached to the polymer chains, and thus, they cannot permeate out of the polymer phase. Conversely, a polymeric anion exchanger contains a high concentration of non-diffusible positively charged quaternary ammonium functional groups. It is well-established that submicron or nanoscale hydrated iron(III) oxide (HFO) particles exhibit high sorption affinity toward both arsenates and arsenites. In this study, commercially available cation and anion exchangers were used as host materials for dispersing HFO nanoparticles within the polymer phase using a technique previously developed. The resulting polymeric/inorganic hybrid sorbent particles were subsequently used for arsenic removal in the laboratory. The most significant finding of the study is that the anion exchanger as a substrate containing dispersed HFO offered substantially higher arsenate removal capacity as compared to the cation exchanger, all other conditions remaining identical. In fact, HFO nanoparticles dispersed within the gel-type cation exchanger were unable to remove arsenic. The Donnan membrane effect resulting from the nondiffusible negatively charged sulfonic acid groups in the cation exchanger did not allow permeation of arsenate into the polymer phase (i.e., arsenate was excluded from the spherical beads dispersed with HFO nanoparticles). On the contrary, anion-exchanger-supported HFO particles or HAIX offered very high arsenic removal capacity; less than 10% of influent arsenic broke through after 10 000 bed vol. HAIX was also amenable to efficient regeneration with 2% NaOH and 3% NaCl and capable of simultaneously removing both perchlorate and arsenic selectively. According to the information in the open literature, HAIX is the first hybrid sorbent that utilizes the Donnan membrane effect of the host material for sorption enhancement. From a generic viewpoint, other metal oxide/metal nanoparticles may also be judiciously embedded in appropriate support materials that would reject or enhance permeation of targeted ionic solutes.  相似文献   
106.
A comparison of the signal intensity fluctuations or scintillation of signal level, observed over two line-of-sight links is presented. These links are situated over Calcutta, DumDum-Andul (6.7 GHz) and Delhi, Delhi-Sonepat (7.6 GHz). The study reveals departures, in the occurrence and variation of the scintillation over the Calcutta path as compared with the path over Delhi. This deviation has been attributed to the large variation in humidity which exists in the coastal region, and also which plays a major role in microwave propagation in the troposphere.  相似文献   
107.
108.
The letter considers modeling methodologies of variable bit-rate (VBR) video sources for performance evaluation of integrated networks. The authors consider an example in which compressed H.261 standard VBR video is transmitted over a local area network carrying both video and data. A group-of-block (GOB) level source model has been constructed using TES (transform-expand-sample)-a new general methodology for generating stationary autocorrelated time series, which can simultaneously capture a prescribed marginal distribution and autocorrelation function. The TES model is used to drive CSMA/CD network simulations for a performance evaluation study. Numerical comparisons with a conventional autoregressive (AR) modeling approach are given  相似文献   
109.
Feature-based stereo correspondence techniques suffer from the major limitation that it is difficult to match along epipolar lines and this often results in a sparse set of depth points. Past researchers attempted to solve this problem through trinocular stereo. In this paper, a new method has been proposed for reducing the sparsity of depth points by orienting the epipolar line of the cameras in a direction that maximizes the number of feature points. The corresponding epipolar axis has been termed as the optimal axis. Our analytical as well as simulation results have established that for a limited edge scenario, the proposed approach can lead to considerable improvement in the number of feature points that can be matched. We have introduced a figure-of-merit for the optimal axis and discussed how it is qualitatively related to the variance of the probability density function (pdf). We have also presented the results of our simulation experiment, termed as the random stick experiment. Finally, we have also shown the results of improved reconstructed surface of a synthetic image using optimal axis alignment.  相似文献   
110.
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