Unified Angular Momentum of Dyons

Unified quaternionic angular momentum for the fields of dyons and gravito-dyons has been developed and the commutation relations for dynamical variables are obtained in compact and consistent manner. Demonstrating the quaternion forms of unified fields of dyons (electromagnetic fields) and gravito-dyons (gravito-Heavisidian fields of linear gravity), corresponding quantum equations are reformulated in compact, simpler and manifestly covariant way

Quaternion Gravi-Electromagnetism

Defining the generalized charge, potential, current and generalized fields as complex quantities where real and imaginary parts represent gravitation and electromagnetism respectively, corresponding field equation, equation of motion and other quantum equations are derived in manifestly covariant manner. It has been shown that the field equations are invariant under Lorentz as well as duality transformations. It has been shown that the quaternionic formulation presented here remains invariant under quaternion transformations.Comment: Key Words: Quaternion, dyons, gravito-dyons, gravi-electromagnetism. PACS No.: 04.90. +e ; 14.80. H

Optimised Cockpit Heat Load Analysis using Skin Temperature Predicted by CFD and Validation by Thermal Mapping to Improve the Performance of Fighter Aircraft

Designing of optimum environmental control system (ECS) plays a major role for increasing performance of fighter aircraft depending upon requirement of engine bleed air for running of ECS. Accurate estimation of cockpit skin temperature for obtaining optimised cockpit heat load helps in estimation of engine bleed air for ECS. Present research evolved a methodology for comparing the theoretically calculated skin temperature with computational fluid dynamics (CFD) analysis to obtain optimum skin temperature. Results are validated by flight tests under critical flight conditions using thermal crayons. Based on which the optimized heat load and bleed air requirements has been computed. Uncertainty analysis of skin temperature measurement for thermal crayons have been undertaken. The results indicate that the theoretical skin temperature is -26.70 per cent as that of CFD estimated skin temperature. Optimized average cockpit heat load at critical flight profiles is 0.74 times the theoretical cockpit heat load, leading to reduction of bleed air requirement by 26 per cent as compared to theoretical. Due to this literature survey has pridicted the increase in performance parameters like increase in bleed air pressure by 78 per cent, increase in thrust by 60 per cent, and decrease in specific fuel consumption (SFC) by 40 per cent to improve the endurance of aircraft. The research has generated governing equations for variation of cockpit heat loads w.r.t aircraft skin temperatures.Defence Science Journal, Vol. 65, No. 1, January 2015, pp.12-24, DOI:http://dx.doi.org/10.14429/dsj.65.720

DEVELOPMENT AND VALIDATION OF STABILITY INDICATING METHOD RP-HPLC METHOD OF ACOTIAMIDE

Objective: The objective of present work was to develop and validate simple, precise, accurate and specific stability indicating method for determination of acotiamide in presence of its degradation products.Methods: An isocratic RP-HPLC method has been developed using C-8 Thermo Hypersil BDS Column (250 x 4.6 mm i.d., 5µparticle size) with the mobile phase composition of acetonitrile: 0.1 % triethylamine in 0.2% formic acid (30: 70) at column oven temperature of 40 °C. The flow rate was 1.0 ml min-1 and effluent was detected at 282 nm. The method was validated in terms of linearity, accuracy, precision, LOD (Limit of Detection), LOQ (Limit of Quantification) and robustness as per ICH guidelines.Results: The method was found to be linear in the range of 10-60µg/ml. Limit of detection and limit of quantification was found to 0.36µg/ml and 1.10 µg/ml.% Recovery was found to be in the range of 99.45%-99.75%and precision less than 2%. The developed method was successfully applied for estimation of Acotiamide in marketed tablet formulation and percentage assay was found to be 100.45%. Acotiamide was subjected to stress degradation under acid, base, neutral hydrolysis, oxidation, dry heat, photolysis conditions. Significant degradation was observed in acid and base degradation.Conclusion: The developed RP-HPLC method was simple, rapid, accurate, precise and stability indicating for the estimation of Acotiamide in bulk and tablet dosage form

STABILITY INDICATING HPTLC METHOD FOR DETERMINATION OF CLEVIDIPINE BUTYRATE IN SYNTHETIC MIXTURE

Objective: To develop and validate stability indicating HPTLC method for determination of clevidipine butyrate in synthetic mixture.Methods: The present study deals with development and validation of stability indicating HPTLC method for estimation of clevidipine butryate. Chromatographic separation was performed on aluminum plate pre coated with Silica Gel 60 F254 using toluene: ethyl acetate (8:2) as mobile phase. TLC scanner was set at wavelength of 370 nm.Results: Retention factor Rf of clevidipine was found to be 0.49. The method was validated as per ICH guidelines. Calibration curve was in the range of 1000-6000ng/band. The correlation coefficient was found to be 0.999. The precision expressed by RSD was less than 2%. The accuracy of method was confirmed by recovery studies using standard addition method and recovery was found to be 99.03-99.57%. The drug was subjected to ICH prescribed hydrolytic, oxidative, photolytic and thermal stress conditions. Clevidipine and its degradation products were well resolved under experimental conditions. The method was validated according to ICH guidelines. The drug showed significant degradation in alkaline and acidic condition and slight degradation in oxidative condition. The drug was stable in thermal condition.Conclusion: A new, Simple, Accurate, Precise, Sensitive and economic stability indicating HPTLC method has been developed and validated for the determination of clevidipine and can be employed for stability indicating analysis

Effect of supply air temperature on conservation of energy in air conditioning of space

In HVAC applications, huge amount of energy is utilized in fans and blowers to maintain the flow. In this paper energy savings associated with air distribution is discussed. In a most commonly used air distribution system, uniform thermal environment in the occupied space is established. An alternative to this method is the under floor air distribution system (UFAD) which is in its fantasy state. Thermal stratification can be established in this method due to the buoyancy flow of the air. In this paper assessment of the impact of temperature sensors in energy savings is done in UFAD system. It is observed that by the placement of temperature sensors in the occupied space, supply air temperature can be controlled while maintaining the comfort conditions. By optimal conditions of the temperature and volume flow, energy savings can be achieved due to reduction in energy requirements in refrigeration and ventilation. The comfort criteria of ASHRAE standard 55-92 is taken