Harnessing Green IT: Principles and Practices

In addition to moving itself in a greener direction and leveraging other environmental initiatives, IT could help create green awareness among IT professionals, businesses, and the general public by assisting in building communities, engaging groups in participatory decisions, and supporting education and green advocacy campaigns. Along these lines, tools such as environmental Web portals, blogs, wikis, and interactive simulations of the environmental impact of an activity could offer assistance. Green IT is an economic, as well as an environmental, imperative. Greening IT is and will continue to be a necessity, not an option. Green IT represents a dramatic change in priority in the IT industry. So far, the industry has been focusing on IT equipment processing power and associated equipment spending. It's not been concerned with other requirements such as power, cooling, and data center space. However, going forward, the IT industry will need to deal with all of the infrastructure requirements and the environmental impact of IT and its use. The challenges of green IT are immense; however, recent developments indicate that the IT industry has the will and conviction to tackle our environmental issues head-on. The IT sector and users must develop a positive attitude toward addressing environmental concerns and adopt forward-looking, green-friendly policies and practices.     

The method of fundamental solutions for inverse 2D Stokes problems

A numerical scheme based on the method of fundamental solutions is proposed for the solution of two-dimensional boundary inverse Stokes problems, which involve over-specified or under-specified boundary conditions. The coefficients of the fundamental solutions for the inverse problems are determined by properly selecting the number of collocation points using all the known boundary values of the field variables. The boundary points of the inverse problems are collocated using the Stokeslet as the source points. Validation results obtained for two test cases of inverse Stokes flow in a circular cavity, without involving any iterative procedure, indicate the proposed method is able to predict results close to the analytical solutions. The effects of the number and the radius of the source points on the accuracy of numerical predictions have also been investigated. The capability of the method is demonstrated by solving different types of inverse problems obtained by assuming mixed combinations of field variables on varying number of under- and over-specified boundary segments.     

Photocatalytic degradation of carbofuran using semiconductor oxides

The photocatalytic degradation of carbofuran (2,3-dihydro-2,2-dimethylbenzofuran-7-yl methylcarbamate) was investigated in an aqueous solution using Degussa P-25 TiO2 and ZnO as photocatalysts. The progress of degradation was monitored using TOC analyzer, HPLC, GC-MS and UV-vis spectrophotometer. The effects of various experimental parameters such as initial concentration of carbofuran, pH of the solution, catalyst loading and light intensity were systematically studied in order to achieve maximum degradation efficiency. The complete mineralization of carbofuran was confirmed by TOC analyzer. The degradation with ZnO showed less efficiency than TiO2. The formation of NO(3)(-) was identified and quantified using HPLC. In addition, four different intermediates formed during the degradation process were also identified and characterized by GC-MS. The mineralization rate was compared with lamps of wavelength 254 and 365 nm under similar conditions. The rate with 254 nm was observed to be very close to that of 365 nm.     

Numerical study of heat and moisture transport through concrete at elevated temperatures

This research article focuses on numerical investigation of heat and moisture transport through concrete exposed to high temperatures such as fire. The conservation equations for moisture and energy transport through concrete have been represented in terms of temperature, pore pressure and vapor content as field variables. As the resulting governing equations are coupled and non-linear, the equations were solved numerically using Galerkin’s weighted residual finite element method and an iterative solution technique. After validating the model, a detailed simulation study has been carried out to understand the role of gradients of temperature, pore pressure and vapor content on heat and moisture transport through concrete exposed to ISO 834 fire curve. Results obtained at the end of 30 minutes exposure of concrete show that the temperature gradients become very steep after 12 minutes of exposure of concrete, which in turn results in increased vapor generation and 93% of vapor generation is completed at the end of 20 minutes. Due to steep temperature gradient along the length of concrete, condensation of vapor takes place which is followed by blockage of pores giving rise to sudden peak pore pressure rise and 97% of peak pore pressure is attained at the end of 18 minutes itself. It is observed that for the initial 18 minutes, the peak pore pressure front and peak vapor content front follow the same path and after 18 minutes the peak vapor content front moves slightly ahead of the peak pore pressure front.     

Heating value of biodiesel: An empirical and theoretical exploration

The heating value of a fuel affects both the brake thermal efficiency and combustion characteristics of an engine. Its value for fuel blend cannot be calculated based on the blend ratio even though the heating values of blend fuels are known. Therefore, a relationship was formulated from the experimental data to predict the heating values of fuel blends. This study was carried out to compute the theoretical heating values of raw as well as purified pungamia oil with different blend ratio by means of SPSS software (ver. 16). The Durbin–Watson (multiple regressions) tests were carried out in the present study to validate the experimental results. The values of density, flash point, viscosity, and percentage of blends were considered an independent variable, and the heating value was considered a dependent variable for the analysis of heating values of different pungamia oil blends with diesel. The theoretically calculated heating values and relationship between the independent variables were around ± 1%. Also, these values were compared with that of the experimental results of other researchers and the variation was only about 2%. Thus, the validations of developed relation with experimental results show good compliance.     

The chlor-alkali process: Work in Progress

The chlor-alkali process has come a long way from the days of the diaphragm and mercury cell process to the present membrane cell process, with huge reduction in power consumption and hence its carbon footprint. Although there is reduction in the release of highly toxic mercury to the environment, there is increased release of less harmful substances such as chloride and chlorate because the membrane cell is less tolerant to contaminants, and hence requires higher purity brine. The technology providers have continued to improve upon the process to reduce power consumption and to reduce the plant’s footprint. This review looks briefly at the three technologies and attempts to look at where we currently are at. All new chlor-alkali plants being built are of the membrane process. This review mentions some of the areas where improvements can be made to the membrane process.     

Influence of <Emphasis Type="Italic">Cissus quadrangularis</Emphasis> Stabilized AgNPs and Its Structural,Optical, Antibacterial Analysis: A Comparative Study

Silver nanoparticles (AgNPs) was synthesized by using AgCl precursor with the stabilizing agent Cissus quadrangularis by precipitation method and the obtained particles were characterized by X-ray diffraction (XRD) analysis, Field Emission Scanning Electron Microscope (FESEM) and UV–Visible (UV–Vis) analysis. The influence of a stabilizing agent on AgNPs was compared with non-stabilized AgNPs through the experimental analysis. The XRD patterns show pure face center cubic structure for both samples, whereas the crystallite size is found to be low in stabilizer used samples. FESEM image and the UV–Vis spectra show less agglomeration and blue shift respectively, for stabilizer used AgNPs, indicating small size particles. Photoluminescence spectra show the emission band at 390 nm for both samples. Antibacterial tests show good activity against Pseudomonas aeruginosa for stabilizer used AgNPs. The study concluded that Cissus quadrangularis can be used as a potential stabilizing agent for preparing AgNPs from AgCl, for optical and biomedical applications.     

Biocomposite based electrode for effective removal of Cr (VI) heavy metal via capacitive deionization

Abstract

This study focuses on the fabrication of biocomposite electrode and removal of Cr (VI) ions from wastewater using a capacitive deionization (CDI) method. The activated carbon (AC) was synthesized from Bael fruit shell (BS). The synthesized AC surface has a macroporous and mesoporous structure with the large specific surface area (617.72?m² g^?1) and high adsorption capacity. The cyclic voltammetry and CDI were performed for the detection and for the removal of chromium (VI) ions, respectively. The lower level of detection of Cr (VI) by a modified electrode was found to be 10 ppt. SEM, BET, and FTIR analyses were performed to explore the surface properties of electrode materials. The removal efficiency was achieved 100% by using biocomposite electrode with an applied potential of 15?V. The highest percent removal mechanism consists of electrosorption and electroreduction due to the affinity between polyvinyl alcohol modified electrode and Cr (VI) ions, under electrochemically faradic process.     

Improvement of tea leaves fermentation with Aspergillus spp. pectinase

The pectinase enzymes isolated from Aspergillus spp., A. indicus, A. flavus and A. niveus were used for fermentation of tea leaves. The enzymes were purified and characterized. The effect of both crude enzyme preparation and purified pectinase enzymes on the improvement of tea leaf fermentation were determined in terms of theaflavin, thearubigin, high polymerized substances, total liquor colour, dry matter content and total soluble solids of the tea produced. The crude enzyme preparations obtained from ethanol precipitation were found to be more effective in improving tea leaf fermentation than the purified pectinase enzymes.