Forced convection heat transfer simulation using dissipative particle dynamics with energy conservation

This paper was presented at the 3rd Micro and Nano Flows Conference (MNF2011), which was held at the Makedonia Palace Hotel, Thessaloniki in Greece. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, Aristotle University of Thessaloniki, University of Thessaly, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute.Dissipative particle dynamics (DPD) with energy conservation was applied to simulate forced convection in parallel-plate channels with boundary conditions of constant wall temperature (CWT) and constant wall heat flux (CHF). DPD is a coarse-grained version of molecular dynamics. An additional governing equation for energy conservation was solved along with conventional DPD equations where inter-particle heat flux accounts for changes in mechanical and internal energies when particles interact with surrounding particles. The solution domain was considered to be two-dimensional with periodic boundary condition in the flow direction. Additional layers of particles on top and bottom of the channel were utilized to apply no-slip velocity and temperature boundary conditions. The governing equations for energy conservation were modified based on periodic fully developed velocity and temperature conditions. The results were shown via temperature profiles across the channel cross section. The Nusselt numbers were calculated from the temperature gradient at the wall using a second order accurate forward difference technique. The results agreed well with the exact solutions to within 2.3%.This work is supported by the National Science Foundation grant (NSF-OISE-0530203)

Prolonged Drug Delivery System of PEGylated PAMAM Dendrimers with a Anti-HIV Drug

Polyamidoamine (PAMAM) dendrimers is a new non viral drug carrier. However their high surface toxicity limits PAMAM dendrimers application in drug delivery. The purpose of present work was aimed to developing and exploring PEGylated G4 and G5 PAMAM dendrimers for anti HIV drug lamivudine. In this study we successfully prepared G4 and G5 PAMAM dendrimers with ethylene diamine core and PEGylated with MPEG for surface modifications. Further physiochemical and physiological parameter such as UV, IR, TEM, DSC, drug entrapment, drug release and hemolytic toxicity of both PEGylated and non PEGylated PAMAM dendrimers were determined and compared. Here the PEGylation of PAMAM dendrimers reduce the surface toxicity and increase the drug loading capacity of PAMAM dendrimers. Moreover PEGylated PAMAM dendrimers had released then drug in controlled and prolonged time. Hence the PEGylated PAMAM dendrimers were found as suitable drug delivery carrier for anti HIV drug lamivudine

Seasonal Variation of Atmospheric Aerosols over Prominent Hotspot Regions in South India by Employing MODIS Data

Mounting the amount of aerosols in the atmosphere is a subject of deep concern all over the globe. This elevated level of aerosol concentrations has proven direct impact on the radiative forcing (Gadhavi and Jayaraman A, 2004) and subsequent climate change. Thus it becomes imperative to study the inter-annual and seasonal variations of aerosols with the aid of remote sensing method by employing MODIS data. This paper pertains to the study of seasonal variations of Aerosol Optical Depths over three different locations which are lying along the same latitude in South India. The five year (2005-2009) observation is presented and it reveals that aerosol abundance has strong dependence on the geography, environment and local climate at a specific region. The variation of aerosol abundance is found to be higher at the coastal region than the region surrounded by land mass

Triangulations and Severi varieties

We consider the problem of constructing triangulations of projective planes over Hurwitz algebras with minimal numbers of vertices. We observe that the numbers of faces of each dimension must be equal to the dimensions of certain representations of the automorphism groups of the corresponding Severi varieties. We construct a complex involving these representations, which should be considered as a geometric version of the (putative) triangulations

Alterations in Serum SOD and CAT Levels in Patients with Breast Cancer

Breast cancers are potentially life-threatening malignancies in women. Development of cancer produces oxidative stress, which increases with disease progression. Hence, studies on antioxidants may be the most promising area of research for this clinical menace. We analysed serum superoxide dismutase (SOD), catalase (CAT) in women with breast cancer. The changes in the levels of serum superoxide dismutase and catalase are measured in breast cancer patients to assess the oxidative stress. A significant increase in the level of superoxide dismutase and a lower catalase activity was observed in all the three categories of breast cancer patients compared to normal individuals. The results suggested that high ROS production supports the oxidative stress in breast cancer. So, the treatment with antioxidants in the initial stages of the disease may be useful as secondary therapy

Variation of CO Column over North Kerala by Exploring MOPITT Data

Carbon Monoxide (CO) is one of the prominent pollutant species mainly produced from of fossil fuel burning and motor vehicles. Being a toxic trace gas, it can considerably affect human health. The rapid increase in CO enhances the production of surface ozone which contributes to global warming. This is the first attempt to retrieve the increase in CO over a column of atmosphere up to 100 mb pressure from the surface using MOPITT version 3 of level 2 data. The increase in column abundance of CO observed is correlated with the increase in vehicles in this region and it gives a positive correlation for the four years of observation from 2004. The prominence of this location of north Kerala is that no major industries are sited within this region and the increase in pollution is solely due to anthropogenic activities.ÂÂ

The Significant Role of CO and NOx in the Tropospheric Ozone Chemistry

Ozone being a greenhouse gas, the chemistry of ozone in the troposphere is considered as an emerging area of investigation after global warming became a reality. The potential role of ozone and its dynamics that changes the atmospheric composition can be retrieved only with the aid of photochemical processes involved in the atmosphere. The various possible chemical reactions that take place at different locations in the atmosphere can significantly change the weather pattern. This is an attempt to review some of the prominent features of the photochemistry of the troposphere and stratosphere

Pharmacognostical Studies and Preliminary Phytochemical Investigations on Roots of Sophora interrupta Bedd., Fabaceae

Sophora interrupta Bedd., is a woody perennial shrub which belongs to the family Fabaceae. Many species of this genus like S. flavescens Ait., and S. japonica L. are used in traditional Chinese medicine. Several phytochemical investigations on this genus revealed the presence of many bioactive constituents like matrine and oxymatrine alkaloids, flavonoids, glycosides and polysaccharides which has medicinal importance. In view of its allied species, their importance in the Chinese medicine and in the absence of its scientifically reported pharmacognostical parameters, the present study attempts to undertake the study of qualitative and quantitative microscopic evaluation of the root along with physicochemical parameters and fluorescence analysis of root powder which helps to establish diagnostic characters and quality parameters for the identification of powdered form of root. Phytochemical evaluation of roots revealed the presence of flavonoids, alkaloids, saponins, glycosides and carbohydrates. TLC and HPTLC profile of Benzene extract was performed for flavonoids

Antibacterial activity of silver nanoparticles synthesized by using whole plant extracts of Clitoria ternatea

This study highlights the synthesis of silver nanoparticles using whole plant extracts of Clitoria ternatea. Antibacterial activity of silver nanoparticles was assessed by using disc diffusion method against Bacillus subtilis, Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae, since Bacillus species and S. aureus strains may cause diarrhoea and an enteropathogenic form of E. coli, and Klebsiella species may cause food poising. The results of this study clearly indicate that silver nanoparticles synthesized from plant extracts of Clitoria ternatea has many pharmaceutical applications for the control of deadly pathogens

Optimal Design of Wastewater Treatment Plant Using Adaptive Simulated Annealing

This paper deals with the application of Adaptive Simulated Annealing (ASA) for the optimal design of the wastewater treatment plant. The plant consists of a trickling filter, an activated sludge aeration vessel and a secondary clarifier.In this work a successful attempt has been made to use the ASA for optimal design of wastewater treatment plant. ASA based optimal design values have been compared with conventional optimization approaches and has been found to yield the lowest total construction cost of wastewater treatment plant. From this work, it has been found that artificial intelligence based optimization techniques such as adaptive simulated annealing is found to be suitable for the optimal design of wastewater treatment plant. @JASE