Unsteady Flow Effects in Combustor Systems

A wide variety of combustion problems, including combustion instabilities and turbulent diffusion flames, appear to involve the entrainment and deformation of laminar flames by large vortex structures in the flow field. First, some details of this process of laminar flame distortion are examined by considering the interactions of time-dependent diffusion flames with two dimensional vortices. Second, Some results on the modelling of the non-steady combustion in burners for aircraft gas turbines are given. The general aim of the work is to develop a one dimensional model applicable to the NASA-Lewis Non-Steady Combustion Rig

The exposure of autoantigens by microparticles underlies the formation of potent inflammatory components: the microparticle-associated immune complexes

Immunoglobulins, antigens and complement can assemble to form immune complexes (IC). ICs can be detrimental as they propagate inflammation in autoimmune diseases. Like ICs, submicron extracellular vesicles termed microparticles (MP) are present in the synovial fluid from patients affected with autoimmune arthritis. We examined MPs in rheumatoid arthritis (RA) using high sensitivity flow cytometry and electron microscopy. We find that the MPs in RA synovial fluid are highly heterogeneous in size. The observed larger MPs were in fact MP-containing ICs (mpICs) and account for the majority of the detectable ICs. These mpICs frequently express the integrin CD41, consistent with platelet origin. Despite expression of the Fc receptor FcγRIIa by platelet-derived MPs, we find that the mpICs form independently of this receptor. Rather, mpICs display autoantigens vimentin and fibrinogen, and recognition of these targets by anti-citrullinated peptide antibodies contributes to the production of mpICs. Functionally, platelet mpICs are highly pro-inflammatory, eliciting leukotriene production by neutrophils. Taken together, our data suggest a unique role for platelet MPs as autoantigen-expressing elements capable of perpetuating formation of inflammatory ICs

Ionic mass transfer at point electrodes located at cathode support plate in an electrorefining cell in presence of rectangular turbulent promoters

Current density plays a major role in deciding the plant size, current efficiency, and energy consumption in electrorefining cells. In general, operating current density will be 40% of the limiting current density. Forced circulation of the electrolyte in the presence of promoters improves the mass transfer coefficient. In the present study, rectangular turbulence promoters are fitted at the bottom side of the cell to improve the mass transfer coefficient at the cathode support plate. The limiting current density technique is used to measure the mass transfer coefficient. The variables covered in the present study are the effects of flow rate, promoter height, and spacing among the promoters. The electrolyte consists of copper sulfate and sulphuric acid. At a regulated flow rate, the electrolyte is pumped from the recirculation tank to the cell through an intermediate overhead tank. The limiting current density increased with an increasing flow rate in the presence of promoters, and thus the overall mass transfer coefficient on the cathode support plate also improved. With an increase in the flow rate of the electrolyte from 6.67 × 10−6 to 153.33 m3/s, limiting current density increased from 356.8 to 488.8 A/m2 for spacing of 0.30 m, with a promoter height of 0.01 m. However, it is noteworthy that when the promoter height is increased from 0.01 to 0.07 m, the overall mass transfer coefficient is found to increase up to 60%, but with the further increase in the promoter height to 0.30 m the mass transfer coefficient starts to decrease. Therefore, the optimized cell parameters are established in this work. The current sustainable concept of employing rectangular turbulence promoters will bring benefits to any precious metal refining or electrowinning tank house electrolytes

Fluorine-induced improvement of structural and optical properties of CdTe thin films for solar cell efficiency enhancement

CdTe thin films of different thicknesses were electrodeposited and annealed in air after different chemical treatments to study the effects of thickness and the different chemical treatments on these films for photovoltaic applications. The thicknesses of the samples range from 1.1 μm to 2.1 μm and the annealing process was carried out after prior CdCl2 treatment and CdCl2+CdF2 treatment as well as without any chemical treatment. Detailed optical and structural characterisation of the as-deposited and annealed CdTe thin films using UV-Vis spectrophotometry and x-ray diffraction reveal that incorporating fluorine in the well-known CdCl2 treatment of CdTe produces remarkable improvement in the optical and structural properties of the materials. This CdCl2+CdF2 treatment produced solar cell with efficiency of 8.3% compared to CdCl2 treatment, with efficiency of 3.3%. The results reveal an alternative method of post-deposition chemical treatment of CdTe which can lead to the production of CdTe-based solar cells with enhanced photovoltaic conversion efficiencies compared to the use of only CdCl2. Keywords: CdTe; CdCl2

ANALYTICAL STANDARDIZATION OF RAJATA BHASMA

Bhasma Kalpana is a unique part of Ayurvedic Rasa shastra. It is a method of converting metals into metallic Bhasma. Metallic Bhasmas are well known for its quick effectiveness, smaller dose and a long shelf life. However if these Bhasmas are not well prepared and analyzed they can be toxic to human body. Therefore Bhasma Pariksha is given in Ayurveda to confirm the well prepared metallic Bhasma, but in this era we need to analyze the Bhasmas on modern parameters too to make it acceptable globally. So in this study prepared Rajata (Silver) Bhasma is analyzed on various parameters i.e. Ayuvedic parameters i.e., Varitaratwa, Rekhapurnatwa, Slakshantwa and Laghutwa and some modern parameters like, pH, Particle size, Zeta Potential, X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Energy dispersive X-ray spectroscopy, Fourier Transform Infra red Spectroscopy (FTIR), U V – Spectroscopy. Results: pH value is 5.6, UV- spectroscopy showed maximum absorption at 302nm, FT-IR of Rajata bhasma reveals the presence of C-H (alkyl), C-N (Aliphatic amine) groups at different wavelengths, Mean Particle size of Rajata bhasma is 2.7nm, Zeta Potential analysis reveals -19.3 mV, X-RD of Rajata bhasma reaveals the major peaks of HgS (Cinnabar), Ag2S (Silver Sulphide), SEM analysis of Rajata bhasma showed small crystalline particles at 5KX & 10KX magnifications, EDX analysis of Rajata bhasma confirmed the presence of elements viz., Sulphur 20.34%, Oxygen 7.43%, Silver 26.72%, Mercury 45.51% by weight

Dual effect of anionic surfactants in the electrodeposited MnO2 trafficking redox ions for energy storage

The dual effect of in-situ addition of anionic surfactants, sodium octyl sulfate (SOS), sodium dodecyl sulfate (SDS) and sodium tetradecyl sulfate (STS) on the microstructure and electrochemical properties of electrolytic manganese dioxide (EMD) produced from waste low grade manganese residue is discussed. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), BET-surface area studies, thermogravimetry-differential thermal analysis (TG-DTA) and Fourier transform infrared spectroscopy (FTIR) were used to determine the structure and chemistry of the EMD. All EMD samples were found to contain predominantly gamma-phase MnO2, which is electrochemically active for energy storage applications. FESEM images showed that needle, rod and flower shaped nano-particles with a porous surface and platy nano-particles were obtained in the case of EMD deposited with and without surfactant respectively. Thermal studies showed loss of structural water and formation of lower manganese oxides indicating high stability of the EMD samples. The cyclic voltammetry and charge - discharge characteristics implied the presence of surfactants enhances the energy storage within the MnO2 structure. Addition of the surfactant at its optimum concentration greatly increased the EMD surface area, which in turn improved the cycle life of the EMD cathode. EMD obtained in the presence of 25, 50, 25 ppm of SOS, SDS, and STS respectively showed an improved cycle life relative to the EMD obtained in the absence of surfactant. EMD obtained without surfactant showed a capacity fade of 20 mAh g(-1) within 15 discharge-charge cycles, while surfactant modified samples showed stable cyclic behavior of capacity 95 mAh g(-1) even after 15 cycles

Estimating process capability index Cpm using a bootstrap sequential sampling procedure

Construction of a confidence interval for process capability index CPM is often based on a normal approximation with fixed sample size. In this article, we describe a different approach in constructing a fixed-width confidence interval for process capability index CPM with a preassigned accuracy by using a combination of bootstrap and sequential sampling schemes. The optimal sample size required to achieve a preassigned confidence level is obtained using both two-stage and modified two-stage sequential procedures. The procedure developed is also validated using an extensive simulation study.<br /

INSIGHT OF METHANOLIC EXTRACT OF VENTILAGO MADERASPATANA LEAVES ON HEPATOPROTECTIVE ACTIVITY UNDER STREPTOZOTOCIN-INDUCED DIABETIC RATS

Objective: The methanolic leaf extract of Ventilago maderaspatana (MEVML, 200 mg/kg body weight [b.w.]) was investigate to hepatoprotective activity under streptozotocin-induced (45 mg/kg b.w.) diabetic (Di) rats. Methods: In the present study, we determined the blood glucose levels, b.w., insulin, creatinine, and bilirubin levels in normal, Di, Di treated with MEVML and positive control rats. Results: The Di rats shown adverse changes in blood glucose levels, b.w., insulin, creatinine, and bilirubin levels when compared to other group rats. Reverse the adverse changes in the above parameters when treated the Di rats with MEVML Conclusion: The MEVML shown anti-diabetic activity and reverse the adverse changes in the above parameters in liver so that the MEVML supported the traditional claim of the hepatoprotective activity under Di condition

CITRUS YELLOW MOSAIC: A TRANSMISSIBLE VIRUS OF CITRUS SPIECES IN INDIA

The yellow mosaic disease of citrus is one of the important diseases causing heavy losses in citrus industry. In the present study, an attempt has been made to analyze certain studies on host range and transmission in citrus yellow mosaic virus infecting Rangapur lime, sweet orange and acid lime. The virus disease of citrus was recognized by mosaic symptoms were noticed in sweet orange, Rangapur lime and acid lime plants. Systemically infected Rangapur lime, sweet orange and acid lime leaves showing characteristic yellow mosaic were collected from AICRP on Tropical Fruits (Citrus), Tirupati. During the present investigations major efforts were made on characterization of CYMV and following information have been generated. The virus under study has a narrow host range. Mechanically sap transmissible from rangpur lime to rangpur lime, sweet orange and acid lime among the citrus hosts and to Canna indica, maize and sorghum in non-citrus hosts. Pure cultures of the virus were developed by sap transmission and there have been used in experiments. The virus culture was maintained on citrus plants. Studies on graft transmission indicated that T-budding (65.56%) and back patch (61.7%) were the best in per cent transmission than leaf patch (42.5%) grafting. The CYMV transmission from sweet orange to sweet orange and Rangapur lime; Rangapur lime to sweet orange and Rangapur lime; and acid lime to acid lime was found better. The transmission of CYMV was very low when it was from acid lime to sweet orange and rangpur lime and vice versa. The citrus mosaic virus was also transmitted by mealy bug, Planococcus citri after 48h acquisition feeding and 4 days inoculation feeding