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51.
Solubilization of selected free fatty acids in palm oil by biodegradable ethoxylated surfactants 总被引:1,自引:0,他引:1
The solubilization of three major components, viz., palmitic, oleic, and linoleic acids, in palm oil by ethoxylated surfactants was investigated. The results were analyzed in terms of the molecular properties of surfactants and free fatty acids (FFAs). It was found that the solubilities of these FFAs in various micellar solutions depend not only on their octanol-water partition coefficients (Kow), but also on their physicochemical properties. The study on the solubilization kinetics was conducted by choosing palmitic acid as a model solubilizate and Tergitol 15-S-7 as the model surfactant. A first-order film diffusion model, which accounts for the direct uptake of organic molecules at a solid surface into surfactant micelles, was adopted to analyze the effect of surfactant on dissolution of palmitic acid. It was observed that the presence of surfactant reduced the mass-transfer coefficient. Instead, the overall mass-transfer rate was enhanced because of the much higher driving force from the increased solubilization capacity. 相似文献
52.
Biological and chemical oxidation characteristics of two kinds ofcoke-oven wastewaters, A and B, discharged from a conventional batch coke-oven and a newly developed continuous coke-oven, respectively, were studied for selecting effective treatment processes of the wastewaters. Pollutants contained in Wastewater-A could be removed by biological process with a sufficient effluent quality, while those which existed in Wastewater-Bcould not be satisfactorily removed. Microbial community structure investigation using the respiratory quinone profile clarified that Pseudomonas putida (dominant quinone: ubiquinone-9) was a dominant species in the biological treatmentsystem. The refractory organic pollutants, existed in Wastewater-B,were mineralized more effectively by Fenton's reagent than by ozone. A wastewater treatment process, in which Fenton's oxidation is followed by a biological treatment, was proposed forthe treatment of Wastewater-B based on the experimental results. 相似文献
53.
Tapinoma indicum (Forel) (Hymenoptera: Formicidae) is a nuisance pest in Asia countries. However, studies on T. indicum are limited, especially in the field of molecular biology, to investigate the species characteristic at the molecular level. This paper aims to provide valuable genetic markers as tools with which to study the T. indicum population. In this study, a total of 143,998 microsatellite markers were developed based on the 2.61 × 106 microsatellites isolated from T. indicum genomic DNA sequences. Fifty selected microsatellite markers were amplified with varying numbers of alleles ranging from 0 to 19. Seven out of fifty microsatellite markers were characterized for polymorphism with the Hardy–Weinberg equilibrium (HWE) and linkage disequilibrium (LD) analysis. All seven microsatellite markers demonstrated a high polymorphic information content (PIC) value ranging from 0.87 to 0.93, with a mean value of 0.90. There is no evidence of scoring errors caused by stutter peaks, no large allele dropout, and no linkage disequilibrium among the seven loci; although loci Ti-Tr04, Ti-Tr09, Ti-Te04, Ti-Te13, and Ti-Pe5 showed signs of null alleles and deviation from the HWE due to excessive homozygosity. In conclusion, a significant amount of microsatellite markers was developed from the data set of next-generation sequencing, and seven of microsatellite markers were validated as informative genetic markers that can be utilized to study the T. indicum population. 相似文献
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55.
A micromethod employing the neutralisation and direct immunofluorescence technique for the detection of antibodies against swine fever in pig serum samples is described. The micromethod is simple and reproducible when compared with the macromethod. A total of 80 blood samples were randomly collected for comparison. The results are promising and reveal a 100 per cent correlation with the macrotechnique. 相似文献
56.
Um SW Kim MS Lim JH Kim SY Seo KM Nam TC 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(12):1283-1284
This study was performed to evaluate the efficacy of acupuncture on induced chronic arthritis of the dog by thermography. Complete Freund's adjuvant was injected into the left knee joint of 8 dogs to induce arthritis. Acupuncture was applied to BL-40, GB-33, GB-34, and LIV-8 once a week for 4 consecutive weeks, from 3 weeks after induction of chronic arthritis, in treatment group. At 3 weeks of acupuncture treatment, skin temperature difference (DeltaT) of treatment group returned to normal range (< 0.3 degrees C), while DeltaT remained high in non-treatment group. Infrared thermography (IRT) is useful to evaluate the treatment of acupuncture for induced canine chronic arthritis. Therefore, it is considered that clinical application of IRT in arthritis treatment would be also valuable. 相似文献
57.
58.
Antigenic differences between H5N1 human influenza viruses isolated in 1997 and 2003 总被引:5,自引:0,他引:5
Horimoto T Fukuda N Iwatsuki-Horimoto K Guan Y Lim W Peiris M Sugii S Odagiri T Tashiro M Kawaoka Y 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(3):303-305
To assess whether the antigenic properties of H5 hemagglutinin (HA) change over time due to antigenic drift, we produced a panel of monoclonal antibodies (mAbs) against the HA of the index H5N1 human influenza A virus, A/Hong Kong/156/97. By immunizing mice with a plasmid expressing this HA and boosting the initial immunization with cell lysates transfected with the plasmid, a total of six hybridomas producing HA-specific mAbs were established: four to the HA1 subunit with hemadsorption-inhibiting activity and two to the HA2 subunit. None of the mAbs to HA1 could bind to the HA of a recent human isolate, A/Hong Kong/213/2003, indicating that there are substantial antigenic differences between the H5N1 human influenza virus isolated in 1997 and that isolated in 2003. 相似文献
59.
Most studies of oocyte apoptosis have been performed in vitro and have employed the method of artificial induction of apoptosis by an anti-cancer agent. However, the process of oocyte death in vivo has not been clearly identified. To investigate the death process in unfertilized oocytes in vivo, we examined the cytochemical change of oocytes collected by oviduct flushing at various intervals after hCG injection. At each collection time, the collected oocytes were phenotypically classified under the microscope into four groups: single-cell oocytes (non-activated and without a nucleus and cytokinesis), activated oocytes (single-, 2- or 4-cell with a nucleus), fragmented oocytes, and dead oocytes. The number of single oocytes decreased and dead oocytes increased with the lapse of time, but the number of activated oocytes or fragmented oocytes did not. Also, most of the dead oocytes observed were single cell. At each time point, single oocytes were stained with anti-tubulin antibody to examine their spindle status. At 24 h after hCG injection, all ovulated oocytes had a normal bipolar spindle, while at 64 h all single-cell oocytes had no spindle. From these observations, we concluded that most oocyte deaths in vivo occur in the single oocyte stage, not in activated or fragmented oocytes. 相似文献
60.