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881.
    
The decomposition of potassium iodide to liberate iodine, the model reaction to study cavitational effects, has been carried out under different cavitational conditions. The effect of various parameters (inlet pressure, flow geometry of orifice plates) on the iodine liberation rate has been studied. It is found that the flow geometry of the orifice plates considerably affects the rate of the iodine liberation. Recommendations are given for the arrangement of the holes in order to achieve maximum benefits from the hydrodynamic cavitation. The experimental results obtained in the present work are very much consistent with the results based on the theoretical model developed for the hydrodynamic cavitation. Due to this fact, it can be said that the model can be extended to any geometry of construction in the hydrodynamic cavitation setup and will be helpful in designing cavitational reactors.  相似文献   
882.
    
In this article, we report on biodegradation studies and the swelling/solubility behavior of gelatin‐grafted polyethylene (PE). The successful synthesis of graft copolymers of PE with gelatin was carried out with benzoyl peroxide as the radical initiator. Biodegradation studies of the grafted PE were carried out via a soil burial test (with and without the addition of urea). Percentage weight loss was studied as a function of time, and we observed that the percentage weight loss increased with time and was higher for urea‐enriched soil samples. Microanalysis of the soil containing the samples was carried out after a specified number of days. An increase in the colonies of microorganisms with increasing number of days was observed. This revealed that the microorganisms fed upon the grafted material, which led to an increase in the percentage weight loss. Hydrolysis of the samples, taken out from the soil after a specified number of days, revealed a continuous loss of weight with increasing number of days. The effect of the degradation of the grafted samples buried in soil and urea‐enriched soil on the growth of plants was studied, and we found that the plants grew normally in the soil containing the grafted material. Swelling studies were made in binary and ternary solvent systems comprising water–ethanol and water–ethanol–dimethyl sulfoxide, respectively, to study the maximum swelling and solubility of the grafted PE. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2008  相似文献   
883.
    
This study reports investigation of the sustained release behavior of a model drug (acetylsalicylic acid) from carboxymethylstarch (CMS) based matrix. CMS was prepared by incorporation of carboxymethyl groups in the starch moiety; by reacting starch with sodium salt of monochloro acetic acid in presence of sodium hydroxide. The in vitro drug release study was performed by United States Pharmacopeia rotating paddle method, at various pH. The rate of drug release from the above matrix was found to increase with increase in pH. Further, the release behavior of the drug from the CMS based matrix was found to be non‐Fickian, n value being between 0.80 and 0.85, suggesting that the release was controlled by a combination of tablet erosion and diffusion of the drug from the swollen matrix. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
884.
    
The present investigation deals with the mechanical, thermal and rheological properties of binary HDPE/EPR blends at various dispersed phase (EPR) concentrations. The effects of EPR concentration on tensile, impact properties of the pure HDPE and HDPE/EPR blends were studied. Analysis of the tensile data in terms of various theoretical models revealed the variation of stress concentration effect with blend composition. Rheological study was carried out to investigate the change in viscosity with shear rate. DSC results show decrease in percent crystallinity of HDPE upon incorporation of EPR except at 20 wt% rubber concentrations wherein the percent crystallinity has shown marginal increment.  相似文献   
885.
886.
    
ABSTRACT

Hydroxyl terminated polybutadiene (HTPB)-based sheet explosive incorporating spherical 3-nitro-1,2,4-triazol-5-one (NTO) as a partial replacement of 1,3,5-trinitro-1,3,5-triazinane (RDX) was investigated. The effect of incorporation of NTO on mechanical properties, sensitivity behavior, and velocity of detonation (VOD) was studied in comparison with a sheet explosive formulation containing 82 wt% RDX, both based on an HTPB-binder system. The replacement of 22 wt% of RDX by spherical NTO resulted in reduced vulnerability to shock as well as impact stimuli. The data demonstrated that the NTO-added formulation was found to be higher shock insensitive compared to the RDX-only formulation. However, ~5% decrease in VOD was observed on incorporation of NTO. Further, the sheet explosive formulations were found insensitive toward friction up to 360 N. Also, molecular dynamics simulations were performed to predict the elastic constants of RDX and NTO and the results revealed that the predicted trend correlated with the experimentally obtained mechanical properties of the formulations.  相似文献   
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Effect of cavitation on chemical disinfection efficiency   总被引:7,自引:0,他引:7  
Jyoti KK  Pandit AB 《Water research》2004,38(9):2248-2257
This study brings out the potential efficacy of hybrid techniques for water disinfection. The techniques studied include hydrodynamic cavitation, acoustic cavitation and treatment with chemicals like hydrogen peroxide and ozone. The hybrid techniques which combine hydrodynamic cavitation, acoustic cavitation and hydrogen peroxide appear to be an attractive alternative to any one technique on its own for the reduction in the heterotropic plate count bacteria as well as indicator microorganisms like the total coliforms, fecal coliforms and fecal streptococci.  相似文献   
890.
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