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Turbomachinery blade optimization using the Navier-Stokes equations
A method is presented to perform aerodynamic design optimization of turbomachinery blades. The method couples a Navier-Stokes flow solver with a grid generator and numerical optimization algorithm to seek improved designs for transonic turbine blades. A fast and efficient multigrid, finite-volume flow solver provides accurate performance evaluations of potential designs. Design variables consist of smooth perturbations to the blade surface. A unique elliptic-hyperbolic grid generation method is used to regenerate a Navier-Stokes grid after perturbations have been added to the geometry. Designs are sought which improve a design objective while remaining within specified constraints. The method is demonstrated with two transonic turbine blades with different types and numbers of design variables
In vivo antioxidant potential of lepidium sativum l. Seeds in albino rats using cisplatin induced nephrotoxicity
The present study was designed to investigate to possible potential nephrocurative, nephroprotective activity and in vivo antioxidant potential of 200mg/kg and 400mg/kg ethanolic extract of Lepidium sativum L. seeds was use to against cisplatin (5mg/kg, i.p.) induced nephrotoxicity. The experimental protocol designed as the animals were divided into six groups (n=6) like control, model control, two curative (200mg/kg and 400mg/kg), and two protective groups (200mg/kg and 400mg/kg, were received vehicle, cisplatin, cisplatin + extract, and extract + cisplatin respectively. After 6th days, blood collected from retro-orbital sinus of rats and determined urea and creatinine level in serum of each group after then rats were sacrificed for quantitative estimation of various enzymes and ATPase content in kidney tissue. A single dose of cisplatin induced loss in body weight, increase urine excretion, increased urea & creatinine level in serum; it was significantly recovered by 200mg/kg and 400mg/kg in curative and protective groups. The enzyme estimation in kidney tissue it found that increase malondialdehyde, superoxide dismutase, catalase and reduced glutathione level, it was significantly monitored by 200mg/kg and 400mg/kg in curative and protective groups. These are defined as vivo antioxidant potential. The level of brush border enzymes like Na+ / K+ ATPase, Ca++ ATPase and Mg++ATPase were found significantly reduced after single dose cisplatin injection. It was overcome by treatment of same extract in curative and protective groups. Finally it is concluded that the present study data conformed nephrotoxicity induced by cisplatin due oxidative stress and ethanolic extract of Lepidium sativum L. seeds may have nephroprotective and curative activity.Keywords: Cisplatin; Nephrotoxicity; urea; creatinine; glutathione; Lipid peroxidatio
In vivo antioxidant potential of lepidium sativum l. Seeds in albino rats using cisplatin induced nephrotoxicity
The present study was designed to investigate to possible potential nephrocurative, nephroprotective activity and in vivo antioxidant potential of 200mg/kg and 400mg/kg ethanolic extract of Lepidium sativum L. seeds was use to against cisplatin (5mg/kg, i.p.) induced nephrotoxicity. The experimental protocol designed as the animals were divided into six groups (n=6) like control, model control, two curative (200mg/kg and 400mg/kg), and two protective groups (200mg/kg and 400mg/kg, were received vehicle, cisplatin, cisplatin + extract, and extract + cisplatin respectively. After 6th days, blood collected from retro-orbital sinus of rats and determined urea and creatinine level in serum of each group after then rats were sacrificed for quantitative estimation of various enzymes and ATPase content in kidney tissue. A single dose of cisplatin induced loss in body weight, increase urine excretion, increased urea & creatinine level in serum; it was significantly recovered by 200mg/kg and 400mg/kg in curative and protective groups. The enzyme estimation in kidney tissue it found that increase malondialdehyde, superoxide dismutase, catalase and reduced glutathione level, it was significantly monitored by 200mg/kg and 400mg/kg in curative and protective groups. These are defined as vivo antioxidant potential. The level of brush border enzymes like Na+ / K+ ATPase, Ca++ ATPase and Mg++ATPase were found significantly reduced after single dose cisplatin injection. It was overcome by treatment of same extract in curative and protective groups. Finally it is concluded that the present study data conformed nephrotoxicity induced by cisplatin due oxidative stress and ethanolic extract of Lepidium sativum L. seeds may have nephroprotective and curative activity.Keywords: Cisplatin; Nephrotoxicity; urea; creatinine; glutathione; Lipid peroxidatio
Experimental and theoretical studies of transport and optical properties of binary mixtures of acetonitrile with some alkyl methacrylates at temperatures from 298.15 to 318.15 K
1457-1469The viscosities, η and refractive indices, nD of pure acetonitrile, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate and of their binary mixtures with acetonitrile as the common component, covering the entire composition range has been measured at temperatures (298.15, 303.15, 308.15, 313.15 and 318.15) K and atmospheric pressure. Using these experimental data, the deviations in viscosity ∆η, deviations in refractive index, ∆nD, deviations in molar refraction, ∆RMhave been calculated. These excess properties are correlated by the Redlich-Kister polynomial equation. The variations of ∆η, ∆nD, ∆RM and with composition and temperature has been discussed in terms of intermolecular interactions existing in these mixtures. Further, the viscosities and refractive indices of these binary mixtures have been calculated theoretically by using various empirical and semi-empirical relations and the results are compared with the experimental findings
IMPACT OF COVID-19 PANDEMIC AND LOCKDOWN ON THE MEAT CONSUMPTION PATTERN IN INDIA: A PRELIMINARY ANALYSIS
The people of India have a wide variety of eating habits that vary according to ethnicity, geography, and culture. The consumption of meat primarily covers the protein requirement of the Indians, and three out of four are non-vegetarians. There is a need to understand the impact of the COVID-19 pandemic and the associated countrywide lockdown on the meat consumption pattern of the Indian non-vegetarians. A countrywide survey was conducted among the consumers to study the impact of COVID-19 on the meat consumption pattern using a self-administered electronic questionnaire distributed through emails and online social networking platforms. A total of 416 responses were collected from the consumers belonging to different states and union territories. The data were analyzed as per the standard procedure. The meat consumption pattern of the non-vegetarians was found to be altered during the COVID-19 pandemic and the lockdown period. The majority of the consumers could not obtain a sufficient quantity of meat and meat products during the lockdown period due to various reasons such as the increased cost and decreased availability of livestock. The myths and rumors associated with meat consumption and the emergence of SARS-CoV-2 further weakened the meat trade in certain areas. Based on the findings of this survey, it is safe to confirm that the meat consumption pattern among Indian consumers was affected badly during the countrywide lockdown
Improving Power Delivery of Grid-Connected Induction Machine Based Wind Generators under Dynamic Conditions Using Feedforward Linear Neural Networks
In the conventional grid-connected Wind Energy Conversion System (WECS), the generator side inverter is typically controlled via Field Oriented Control (FOC), while Voltage Oriented Control (VOC) controls the grid side inverter. However, robust operation cannot be guaranteed during sudden changes in wind speeds and weak grid connections. This paper presents a novel method to improve the overall dynamic performance of on-grid induction machine-based wind generators. An online mechanical parameter estimation technique is devised using Recursive Least Squares (RLS) to compute the machine inertia and friction coefficient iteratively. An adaptive feedforward neural (AFN) controller is also proposed in the synchronous reference frame, which is constructed using the estimated parameters and the system's inverse. The output of the neural controller is added to the output of the speed PI controller in the outer loop of the FOC to enhance the speed response of the wind generator. A similar approach is taken to improve the classical VOC structure for the grid-side inverter. In this case, the RLS estimates the equivalent Thevenin's grid impedance in real-time. As for the adaptive action, two identical neural networks are integrated with the inner loop direct and quadrature axis current PI controllers. Under nominal operating conditions, it is observed that the PI+AFN provides a faster settling time for the generator's speed and torque response. Upon being subjected to variations in the wind speed, the PI+AFN outperforms the classical PI controller and attains a lower integral-time error. In addition, the proposed PI+AFN controller has a better ability to maintain the grid-side inverter stability during stochastic variations in grid impedance. One significant advantage of the proposed control approach is that no data for training or validation is required since the neural network weights are directly the output of the RLS estimator. Hardware verification for the improved FOC for wind generators using the adaptive controller is also made using the DSPACE 1007 AUTOBOX platform
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