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741.
A novel allyl functionalized dicyanate ester resin bearing sulfoxide linkage was synthesized. The monomer was characterized by Fourier Transform Infrared (FT‐IR) Spectroscopy, 1H‐, and 13C Nuclear Magnetic Resonance (NMR) spectroscopy and elemental analysis. The monomer was blended with bismaleimide (BMI) at various ratios in the absence of catalyst. The cure kinetics of one of the blends was studied using differential scanning calorimetry [nonisothermal] and the kinetic parameters like activation energy (E), pre‐exponential factor (A), and the order of the reaction (n) were calculated by Coats‐Redfern method and compared with those calculated using the experimental Borchardt‐Daniels method. The thermal stability of the cured dicyanate, BMI, and the blends was studied using thermogravimetric analyzer. The initial weight loss temperature of dicyanate ester is above 380°C with char yield of about 54% at 800°C. Thermal degradation of BMI starts above 463°C with the char yield of about 68%. Inclusion of BMI in cyanate ester increases the thermal stability from 419 to 441°C. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
742.
Sheetal U. Jadhav Mital U. Jadhav Anuradha N. Kagalkar Sanjay P. Govindwar 《Journal of the Chinese Institute of Chemical Engineers》2008,39(6):563-570
A consortium-GB containing two microorganisms Galactomyces geotrichum MTCC 1360 and Bacillus sp. VUS was able to degrade sulfur-containing dye Brilliant Blue G, optimally at pH 9 and temperature at 50 °C. The ability of consortium-GB to work at higher temperature and pH ranges will help in using this consortium for removal of the dye from textile effluent. Malt extract, peptone and beef extract were found to be the best additional carbon and nitrogen sources. Brilliant Blue G caused enhancement of the riboflavin reductase among the enzyme activities studied. Biodegradation was confirmed by analyzing the product using UV–vis, HPLC, and FTIR. The GC–MS study revealed a pathway of Brilliant Blue G with release of (4-ethoxy-phenyl)-phenyl-amine and 3-ethylaminomethyl-benzenesulfonic acid as final metabolites formed by the consortium-GB. GC–MS analysis indicated the formation of 3-{[ethyl-(3-methyl-cyclohexa-2,5-dienyl)-amino]-methyl}-benzenesulfonic acid as a product by G. geotrichum MTCC 1360 alone and (4-benzylidene-3-methyl-cyclohexa-2,5-dienylidene)-methyl-amine by Bacillus sp. VUS alone. Phytotoxicity revealed nontoxic nature of the metabolites. These results indicate the high potential of the consortium-GB to serve as an excellent biomass for the use in Brilliant Blue G dye removal. 相似文献
743.
M. D. Mathew J. Ganesh Kumar V. Ganesan K. Laha 《Metallurgical and Materials Transactions A》2014,45(2):731-737
Small punch creep (SPC) studies have been carried out to evaluate the creep properties of 316LN stainless steel (SS) at 923 K (650 °C) at various stress levels. The results have been compared with uniaxial creep rupture data obtained from conventional creep tests. The minimum deflection rate was found to obey Norton power law. SPC rupture life was correlated with uniaxial creep rupture life. The influence of nitrogen content on the creep rupture properties of 316LN SS was investigated in the range of 0.07 to 0.14 wt pct. SPC rupture life increased and the minimum deflection rate decreased with the increase in nitrogen content. The trends were found to be in agreement with the results obtained from uniaxial creep rupture tests. These studies have established that SPC is a fast and reliable technique to screen creep properties of different experimental heats of materials for optimizing the chemical composition for developing creep-resistant materials. 相似文献
744.
Gina C. Kim Cyril Rakovski Fred Caporaso Anuradha Prakash 《Journal of food science》2014,79(1):S81-S91
Grapes (Vitis vinifera var. Sugraone and Vitis labrusca var. Crimson Seedless) were treated with 400, 600, and 800 Gy and the effects on physicochemical factors were measured alongside sensory testing during 3 wk of storage. Significant changes in texture and color with irradiation and age were measured but little visual difference was seen between control and irradiated grapes. However, age had a greater effect on firmness than irradiation for Sugraone grapes. Irradiation did not significantly (P ≤ 0.05) affect the SSC/TA ratio, which increased during storage. The trained panel detected significant changes in the berry texture and rachis color but rated sweetness and flavor significantly higher (P ≤ 0.05) for irradiated Sugraone as compared to the control. Consumers liked both the untreated and 800 Gy treated Sugraone grapes, but liked the untreated grapes more for texture (P ≤ 0.05). However, there was no difference in liking between irradiated (600 Gy or 800 Gy) and control samples of Crimson Seedless for any attribute. The results show that there are varietal differences in response to irradiation but the overall maintenance in quality of irradiated grapes during 3 wk of storage indicates that irradiation can serve as a viable phytosanitary treatment. 相似文献
745.
Effect of Delayed Icing on the Microbiological Quality of Tropical Fish: Barracudas (Sphyraena barracuda) 总被引:1,自引:0,他引:1
G. Jeyasekaran P. Ganesan K. Maheswari R. Jeya Shakila D. Sukumar 《Journal of food science》2004,69(7):197-200
ABSTRACT: Effect of delayed icing on the bacteriological quality of a commercially important tropical fish, barracuda ( Sphyraena barracuda ), was studied. Fish obtained from the fish-landing center of Tuticorin, India, were immediately brought to the laboratory and divided into 2 lots. One lot was immediately iced (II) and the other lot was left at ambient temperature (32 ± 2 °C) for 6 h and then iced (DI). Immediate icing extended the shelf life of barracuda by 6 d. In II fish, the total bacterial count increased from 103 to 106 colony-forming units (CFU)/g; total lactics and total histamine formers appeared on day 7 and 3, respectively, and the total coliforms were very low. While in DI fish, total bacterial count remained at 106 CFU/g. Total lactics, total histamine formers, and total coliforms were high. 相似文献
746.
An intervention study in obese mice with astaxanthin, a marine carotenoid--effects on insulin signaling and pro-inflammatory cytokines 总被引:1,自引:0,他引:1
Astaxanthin (ASX), a xanthophyll carotenoid from the marine algae Hematococcus pluvialis, has anti-obesity and insulin-sensitivity effects. The specific molecular mechanisms of its actions are not yet established. The present study was designed to investigate the mechanisms underlying the insulin sensitivity effects of ASX in a non-genetic insulin resistant animal model. A group of male Swiss albino mice was divided into two and fed either a starch-based control diet or a high fat-high fructose diet (HFFD). Fifteen days later, mice in each dietary group were divided into two and were treated with either ASX (6 mg kg(-1) per day) in olive oil or olive oil alone. At the end of 60 days, glucose, insulin and pro-inflammatory cytokines in plasma, lipids and oxidative stress markers in skeletal muscle and adipose tissue were assessed. Further, post-receptor insulin signaling events in skeletal muscle were analyzed. Increased body weight, hyperglycemia, hyperinsulinemia and increased plasma levels of tumor necrosis factor-α and interleukin-6 observed in HFFD-fed mice were significantly improved by ASX addition. ASX treatment also reduced lipid levels and oxidative stress in skeletal muscle and adipose tissue. ASX improved insulin signaling by enhancing the autophosphorylation of insulin receptor-β (IR-β), IRS-1 associated PI3-kinase step, phospho-Akt/Akt ratio and GLUT-4 translocation in skeletal muscle. This study demonstrates for the first time that chronic ASX administration improves insulin sensitivity by activating the post-receptor insulin signaling and by reducing oxidative stress, lipid accumulation and proinflammatory cytokines in obese mice. 相似文献
747.
Quantitative and qualitative studies on the bacteriological quality of Indian white shrimp (Penaeus indicus) stored in dry ice 总被引:1,自引:0,他引:1
Indian white shrimp (Penaeus indicus) stored in dry ice at the 1:1 ratio were found to be organoleptically suitable for consumption when they were stored for 24 h without reicing. Shrimp stored in water ice at the 1:1 ratio (as control) were acceptable up to 18 h. Shrimp stored in a combination of dry ice and water ice at the ratio of 1:0.2:0.5 were also found to be acceptable up to 24 h. Total bacterial load ranged from 10(6) to 10(9) cfu g(-1), while total psychrophiles ranged from 10(3) to 10(6) cfu g(-1). Total lactics were found in the levels of 10(2)-10(6) cfu g(-1). H(2)S producers were from 10(3) to 10(5) cfu g(-1). Lowest temperature of -4.8 degrees C was observed in shrimps stored in dry ice at 1:1 ratio. Bacterial flora associated with fresh raw shrimp were Aeromonas, Pseudomonas, Vibrio, Flavobacterium and Serratia. Aeromonas constituted 38% of the flora in raw shrimp. Flavobacterium (43%), Pseudomonas (47%) and Pseudomonas (38%) were the dominant bacterial flora in the shrimp stored in dry ice at 1:1 ratio, in the combination package, and in water ice at 1:1 ratio, respectively. 相似文献
748.
Sung-Min Won Eunju Park Jin-Ju Jeong Raja Ganesan Haripriya Gupta Yoseph Asmelash Gebru SatyaPriya Sharma Dong-Joon Kim Ki-Tae Suk 《International journal of molecular sciences》2021,22(15)
In chronic liver disease, the causative factor is important; however, recently, the intestinal microbiome has been associated with the progression of chronic liver disease and the occurrence of side effects. The immune system is affected by the metabolites of the microbiome, and diet is the primary regulator of the microbiota composition and function in the gut–liver axis. These metabolites can be used as therapeutic material, and postbiotics, in the future, can increase or decrease human immunity by modulating inflammation and immune reactions. Therefore, the excessive intake of nutrients and the lack of nutrition have important effects on immunity and inflammation. Evidence has been published indicating that microbiome-induced chronic inflammation and the consequent immune dysregulation affect the development of chronic liver disease. In this research paper, we discuss the overall trend of microbiome-derived substances related to immunity and the future research directions. 相似文献
749.
ABSTRACT Ambient air oxidation leads to lower Fischer assay oil yields and often lower process yields from retorting of eastern oil shales. Slight changes in the kerogen and mineral matter of the oil shale and in its pyrolysis products, both liquid and gaseous, were evident following autoxidation. Experimental observations suggest that the hydrogen deficiency of eastern kerogen, as compared to western kerogen, makes its synfuel potential (by Fischer assay) a more sensitive function of the degree of oxidation. A better yield of oil from oxidized eastern oil shale could be obtained by dissolving away sulfates and other water soluble oxidized materials prior to retorting. The air oxidation of pyrite was demonstrated by SEH, and addition of iron(II) sulfate was shown to reduce assay oil yields. Such observations suggest that combusted shale may not always be a suitable heat transfer agent for atmospheric pressure retorting applications. 相似文献
750.
The present work deals with removal of hexavalent chromium from synthetic effluents in a batch stirred electrocoagulation cell with iron-aluminium electrode pair coupled with adsorption using granular activated carbon (GAC). Several working parameters such as pH, current density, adsorbent concentration and operating time were studied in an attempt to achieve higher removal capacity. Results obtained with synthetic wastewater revealed that most effective removal capacities of chromium (VI) could be achieved when the initial pH was near 8. The removal of chromium (VI) during electrocoagulation, is due to the combined effect of chemical precipitation, coprecipitation, sweep coagulation and adsorption. In addition, increasing current density in a range of 6.7-26.7mA/cm2 and operating time from 20 to 100min enhanced the treatment rate to reduce metal ion concentration below admissible legal levels. The addition of GAC as adsorbent resulted in remarkable increase in the removal rate of chromium at lower current densities and operating time, than the conventional electrocoagulation process. The method was found to be highly efficient and relatively fast compared to existing conventional techniques. 相似文献