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Banana agricultural waste is one of the potential lignocellulosic substrates which are mostly un-utilized but sufficiently available in many parts of the world. In the present study, suitability of banana waste for biofuel production with respect to pretreatment and reducing sugar yield was assessed. The effectiveness of both acid and alkali pretreatments along with autoclaving, microwave heating and ultrasonication on different morphological parts of banana (BMPs) was studied. The data were statistically analyzed using ANOVA and numerical point prediction tool of MINITAB RELEASE 14. Accordingly, the optimum cumulative conditions for maximum recovery of reducing sugar through acid pretreatment are: leaf (LF) as the substrate with 25 min of reaction time and 180 °C of reaction temperature using microwave. Whereas, the optimum conditions for alkaline pretreatments are: pith (PH) as the substrate with 51 min of reaction time and 50 °C of reaction temperature using ultrasonication (US).

Coal coking, precious metals mining and nitrile polymer industries generate over several billion liters of cyanide-containing waste annually. Economic and environmental considerations make biological technologies attractive for treatment of wastes containing high organic content, in which the microbial cultures can remove concentrations of organics and cyanide simultaneously. For cyanide and phenol bearing waste treatment, an upflow anaerobic sludge blanket reactor has been developed, which successfully removed free cyanide 98% (with feed concentration of 20 mg 1(-1)) in presence of phenol. The effect of cyanide on phenol degradation was studied with varying concentrations of phenol as well as cyanide under anaerobic conditions. This study revealed that the methanogenic degradation of phenol can occur in the presence of cyanide concentration 30-38 mg 1(-1). Higher cyanide concentration inhibited the phenol degradation rate. The inhibition constant Ki was found to be 38 mg 1(-1) with phenol removal rate of 9.09 mg 1(-1.) x h.

Optimal Power Flow (OPF) problem in electrical power system is consider as a static, non-linear, multi-objective or a single objective optimization problem. As the power industrial companies have been moving in to a more competitive environment, OPF has been used as a tool to define the level of the inter utility power exchange. Basically, this research work provide a new approach to solve the single objective OPF problem considering critical objective function of reactive loss minimization for utility/industrial companies, while satisfying a set of system operating constraints, including constraints dedicated by the electrical network. Particle Swarm Optimization (PSO) has been used for this purpose. Particle Swarm Optimization (PSO) is a population based stochastic optimization technique. The system is initialized with a population of random feasible solutions and searches for optima by updating generations. The IEEE-30 bus system is considered throughout this research work to test the proposed algorithm.

Sol-gel based processes have been developed for the fabrication of nuclear fuel materials, namely, the oxides, carbides and nitrides of uranium, plutonium and thorium as well as their solid solutions. These processes have the advantage of being free from using radioactive powder and being amenable for adaptation to remote handling. The fuel microspheres prepared through sol-gel processes can be vibrocompacted to form sphere-pac fuel pins or compacted into pellets for stacking in a fuel pin. Among the sol-gel processes, the external gelation and internal gelation processes are being used in plant scale for the preparation of kernels of coated particle fuels for high temperature gas cooled reactors. They also have the potential to be used for the fabrication of fast reactor fuels as well as fuels containing minor actinides for the transmutation reactors.

The study presented here focuses on the phenomenon of water sensitivity of sandstones containing swelling and nons-welling clays. This paper describes results of an ongoing investigation on the mechanisms of permeability reduction in sandstones containing swelling and non-swelling clays. These studies show that the critical salt concentrations of sodium chloride and potassium chloride needed to prevent loss of permeability in sandstones containing swelling clay (Stevens sandstone) are considerably higher than the corresponding values for Berea sandstone. A critical salt concentration of calcium chloride is shown to exist for these sandstones. As opposed to Berea sandstone, pH control may not be sufficient to eliminate loss of permeability in swelling clay sandstones. The results show that crystalline swelling of smectites/mixed layer clays induces significant permeability reduction in the swelling clay sandstones considered in this paper.

The problem of E-waste has forced Environmental agencies of many countries to innovate, develop and adopt environmentally sound options and strategies for E-waste management, with a view to mitigate and control the ever growing threat of E-waste to the environment and human health. E-waste management is given the top priority in many developed countries, but in rapid developing countries like India, it is difficult to completely adopt or replicate the E-waste management system in developed countries due to many country specific issues viz. socio-economic conditions, lack of infrastructure, absence of appropriate legislations for E-waste, approach and commitments of the concerned, etc. This paper presents a review and assessment of the E-waste management system of developed as well as developing countries with a special emphasis on Switzerland, which is the first country in the world to have established and implemented a formal E-waste management system and has recycled 11kg/capita of WEEE against the target of 4kg/capita set by EU. And based on the discussions of various approaches, laws, legislations, practices of different countries, a road map for the development of sustainable and effective E-waste management system in India for ensuring environment, as well as, occupational safety and health, is proposed.

Background: Gallstone disease known as cholelithiasis is the most common digestive surgical disorder and account for an important part of health care expenditure. Attempt was made to analyse the gallstone for typing depending upon the composition. Aims & objectives: The main objective of this study was to see the prevalence of different types of gallstone in Nepal and to correlate them with the clinical findings. Materials & methods: Gallstones of 80 different patients who underwent cholecystectomy for cholelithiasis were collected from 20th January 2005 to 16th May 2006 in Department of Pathology, Kathmandu Medical College Teaching Hospital. Detailed history was taken. Stones were analyzed with chemical and enzymatic methods using clinical spectrophotometer. Results & conclusion: The most commonly involved age group for cholelithiasis (32.5%) is found to be 30-39 years with a female predominance (M: F=1:3.2). Cholelithiasis was found more commonly among non-vegetarian with the vegetarian: non-vegetarian ratio 1:9. Mixed type stone was found to be the most common type of stone comprising 78.75%, followed by cholesterol stone 12.5%, Brown pigment stone 7.5% and Black pigment stone 1.25%.Key words: Gallbladder; cholelithiasis; Gallstone DOI: 10.3126/kumj.v7i3.2736 Kathmandu University Medical Journal (2009) Vol.7, No.3 Issue 27, 268-271

The purpose of the SAMBA project, running from January 2007 to February 2009, was to create a framework for allowing local communities and citizens (including low income population) to access community-oriented content and services by means of iDTV channels, specifically MHP over DVB-T. This paper summarises the project and the experiences gained from it.

Using the noncompact SO(2,1)∼SU(1,1) Lie algebra the Schwinger–de Witt kernels for massive spin‐1/2 fields are obtained in some classical background gravitational fields. The method makes use of the Schwinger–de Witt proper time representation and Baker–Campbell–Hausdorff formulas.

The Green function for a spin-1/2 charged particle in the presence of an external plane wave electromagnetic field is calculated by algebraic techniques in terms of the free-particle Green function.

Present study describes the treatment of molasses spentwash and its use as a potential low cost substrate for production of biopolymer polyhydroxybutyrate (PHB) by waste activated sludge. Fluorescence microscopy revealed the presence of PHB granules in sludge biomass which was further confirmed by fourier transform-infra-red spectroscopy (FT-IR) and (13)C nuclear magnetic resonance (NMR). The processing of molasses spentwash was carried out for attaining different ratios of carbon and nitrogen (C:N). Highest chemical oxygen demand (COD) removal and PHB accumulation of 60% and 31% respectively was achieved with raw molasses spentwash containing inorganic nitrogen (C:N ratio=28) followed by COD removal of 52% and PHB accumulation of 28% for filtered molasses containing inorganic nitrogen (C:N ratio=29). PHB production yield (Y(p/s)) was highest (0.184 g g(-1) COD consumed) for deproteinized spentwash supplemented with nitrogen. In contrast, the substrate consumption and product formation were higher in case of raw spentwash. Though COD removal was lowest from deproteinized spentwash, evaluation of kinetic parameters suggested higher rates of conversion of available carbon to biomass and PHB. Thus the process provided dual benefit of conversion of two wastes viz. waste activated sludge and molasses spentwash into value-added product-PHB.

In this paper, we present a new approach for modeling filtrate invasion during the drilling of a horizontal well with fractures, and the impact of its cleanup on well performance. The approach incorporates the drilling schedule and the experiment-based dynamic filter-loss data into multiphase reservoir simulator. Unlike the traditional leak off model in which the assumption of the piston-like displacement in the filtrate invaded zone, the fluid flow in the invaded and the reservoir zones are described by use of more realistic two-phase oil-gas flow equations which are solved under the dynamic boundary conditions of the leak off model and time-varying reservoir exposure due to drilling, tripping, completions and workovers. Since, impact of fractures on both invasion and flow-back is more pronounced in tight formations, this paper will focus on such formations. In real drilling process, the initial dynamic mud-cake formation is critical for controlling filtrate loss. A dynamic fluid-loss model which reflects the spurt loss, non-Darcy and non-Newtonian characteristics of filtrate flow through the mud cake is coupled with the reservoir simulator. Mud properties and different events influence cake compression, dynamic cake deposition and cake erosion as well. The application of the dynamic filtrate loss model avoids the complexity in building a multi-parameter mathematical mud cake model without loss of generality. As in previous works, the dynamic filtrate loss model is based on actual special core tests. Sensitivity analysis is conducted to study the influence of dynamic leakoff coefficient on the saturation distributions during the filtrate invasion and flowback. In existing experiments, only the leakoff coefficients for matrix are measured. The extrapolation of the dynamic leakoff coefficients for simulation of fluid loss into intersecting fractures is discussed. Driven by Buckley-Leverett equations, theoretical analysis is presented to emphasize the quantitatively spatial correlation between the invaded filtrate saturation and spatial permeability reduction in the invaded zone. Moreover, well performance influenced by the water blocking, relative permeability alteration and the damaged permeability variation are simulated. A horizontal well example is used to illustrate the flexibility of this approach. The results show that the dynamic leakoff coefficient significantly impacts the clean-up and well performance. The results also shed light on the relative value of hydraulically fracturing a conventional over-balanced drilled horizontal well, versus hydraulically fracturing the well after it is drilled underbalanced.

A steady model for the evaluation of external liquid film diffusion and internal pore diffusion effects in an immobilized biofilm system under continuous mode of operation was developed. The model takes into account, substrate diffusion through external liquid film and biofilm. Average rate of substrate consumption in the biofilm was considered. The overall efficiency of the biofilm was mathematically represented by considering the combined effects of substrate penetration and substrate utilization in the biofilm. The model was illustrated using a case study of pyridine biodegradation in a rotating biological contactor immobilized with pyridine degrading microbial film. The model is able to effectively predict both internal and external mass transfer effects in an immobilized biofilm system.

This paper enhances a software based framework to dynamically scale power and performance with high accuracy in a resource limited embedded system, like cellular phones and PDAs. Key challenges for such a framework are accurate forecasting of dynamic resource demands inherent in the workloads. In this paper we describe three innovative methods: (1) smart forecast method based on linear and non-linear filtering models; (2) policy decision based on high fidelity memory and computation characterization; and (3) adaptive sampling period to adapt to dynamic changes in the workloads. Power and performance framework driven by the proposed algorithms reduces power consumption thus improving battery lifetime for the end-user.

The prospect of dynamic reservoir characterization using flow and pressure data gathered during underbalanced drilling (UBD) is a powerful driver for implementation of UBD. The mathematical aspects of this complex, ill-posed, inverse problem have been the subject of research in the past decade. This paper focuses on practical, field implementation of UBD reservoir characterization, and the problems that consequently arise. Interpretation of data from UBD is made difficult by transducer errors, operational transients, and noise in data. It is therefore often very difficult to interpret the reservoir characteristics from the instantaneous productivity index (PI). In this paper, we introduce a parameter known as the Rate Integral Productivity Index (RIPI), which borrows from the theory of rate-transient analyses. The mathematical and physical basis of RIPI and its relationship to the instantaneous PI are presented. The behavior of RIPI and its implications for reservoir characterization are discussed. RIPI de-noises the data, and scales the problem such that the trends in data are more obvious, enabling robust interpretation of UBD data, and increasing the confidence in calls made regarding reservoir characteristics. Application of RIPI to field data is illustrated through several examples. Data acquisition, processing, and preparation for UBD reservoir characterization are discussed. In particular, the importance of filtering, de-noising, and identifying and excluding operationally induced transients is described. Limitations imposed by the data gathering methods are highlighted. It is shown that the ability of RIPI to reduce noise in raw PI data allows trends to be read more easily. The use of RIPI for static and dynamic characterization of supermatrix features (such as fractures, thief zones, etc.) is illustrated. The limitations of the approach and future trends are discussed.

This paper enhances a software based framework to dynamically scale power and performance with high accuracy in a resource limited embedded system, like cellular phones and PDAs. Key challenges for such a framework are accurate forecasting of dynamic resource demands inherent in the workloads. In this paper we describe two innovative methods: (1) smart forecast method based on linear and non-linear filtering models and (2) adaptive sampling period to adapt to dynamic changes in the workloads. Power and performance framework driven by the proposed algorithms reduces power consumption thus improving battery lifetime for the end-user.

Wastewater generated during coke-oven gas cleaning operations in the integrated steel plant contains phenol, cyanide, thiocyanate, and also oil and grease. Although the activated sludge process is widely practiced for biological treatment of coke-oven wastewater, it was observed during the evaluation of performance of full scale coke-oven wastewater treatment plant that oil contamination and poor sludge settleability had resulted in poor maintenance of the activated sludge process. Keeping these aspects in view, treatability studies were conducted and an alternative treatment process is proposed. With these corrective measures the coke-oven wastewater treatment plant will give desired performance. In this paper we present results of the performance evaluation, data on treatability studies and alternative treatment process scheme.

Different techniques of preparation of alumina sols are briefly described. Preparative techniques of alumina monoliths, microspheres etc by using precursor sols are discussed.

The enhancement of the deuteron-deuteron fusion rate is estimated for a coherent interaction mechanism under realistic experimental conditions. The extension of this mechanism to (n, γ) reactions i...

Fluorescence spectra of laser dyes coumarin 1 and coumarin 102 in methanol and ethanol were studied at high pressures using diamond anvil cell. These dyes show a large frequency shift with pressure toward the red end. While the fluorescence maxima vary smoothly with pressure up to the glassification pressure followed by an expected change of slope at this pressure for coumarin 102, coumarin 1 exhibits a pressure-independent regime prior to glassification. This is attributed to a conformational change taking place in coumarin 1 at about 1 GPa

We report for the first time the direct observation of an apparently first-order phase transition in amorphous silica from the low density amorphous phase to the high density amorphous phase with a discontinuous volume change of about $20%$ from the dilatometric measurements using the piston cylinder apparatus at 36 kbar and 680 \ifmmode^\circ\else\textdegree\fi{}C. Our Raman spectroscopy measurements on the retrieved samples quenched from high pressure and high temperature experiments do not show any Raman peaks indicating a large modification in the intermediate range order in the structure of amorphous silica.

The possibility of acoustic plasmons leading to nonequilibrium high-temperature superconductivity is considered in the system Pd-H(D).

A coherent interaction mechanism is proposed for the enhancement of the deuteron-deuteron fusion reaction rate in a crystalline Pd-D lattice.

The objective of this work was to provide a more accurate prediction of well and reservoir performance for gas and gas condensate reservoirs by investigating near-wellbore effects. Specifically, the effects of non-Darcy flow and changes in relative permeability due to interfacial tension (IFT), and flow rate (modeled based on capillary number) on well productivity are considered. These effects are shown to be important factors affecting the productivity index (PI) of gas condensate wells. When only non-Darcy effects are considered, the condensate bank can cause an order of magnitude reduction in the PI. Hence, immediate remediation steps might be necessary for formations with high non-Darcy flow coefficients. The reduction in PI with increasing non-Darcy flow coefficient is also highly non-linear. The relative permeability improvement obtained at high capillary numbers on the other hand counteracts the PI reduction due to non-Darcy flow effects. This effect reduces the drop in PI due to condensate buildup and makes the drop in PI more gradual. Hence, both effects should be considered while studying the production performance of a gas condensate reservoir. The capillary number effect can in some cases overshadow the two-phase non-Darcy effects. Interestingly, when both non-Darcy and capillary number effects are present, the rate of decrease in the PI at or below the dew point is smaller than the case with the capillary number effect only. A case study of a lean-gas condensate reservoir, similar to the Arun field, was considered and a history match with the production data was performed. Simulation results are presented which clearly show that accurate prediction of PI based on laboratory measurements is possible using both non-Darcy and capillary number effects.

An unstructured finite volume methodology is presented for simulating radiant heat transfer based on the discrete-ordinate formulation. The methodology is conservative and is applicable to structured, unstructured, or hybrid grids. Based on the conventional Sn discreteordinates method, and the control-angle finite volume method, the spatial and angular discretizations of the Radiative Transfer Equation (RTE) are described for a general grid topology. Possibilities for accurate and efficient treatment of the truncated solid angles at domain boundaries are discussed. The proposed methodology has been integrated into a general purpose 'Computational Fluid Dynamics (CFD) code. The accuracy, of the present numerical approach is illustrated using 2-D and 3-D benchmark and validation cases. The predictions compare favorably with established numerical and analytical solutions.

Batch kinetic studies were carried out on rhamnolipid biosurfactant production from synthetic medium, industrial wastes viz. distillery and whey waste as substrates. The results indicated that the specific growth rates (μ max) and specific product formation rates (V max) from both the wastes are comparatively better than the synthetic medium, revealing that both the industrial wastes (distillery and whey) can be successfully utilized as substrates for biosurfactant production.

A novel Rotating Rope Biofilter (RRB) has been developed especially for the treatment of Volatile Organic Compounds (VOCs) at higher loadings and characterised by high volatility along with high water solubility. The RRB provides a higher interfacial area (per unit reactor liquid volume) along with high oxygen mass transfer rate, greater microbial culture stability, and consequently higher substrate loadings and removal rates in comparison with other conventional reactors (e.g. biofilters) widely used for the treatment of VOCs. Pyridine was used as a model compound to demonstrate the enhanced performance of the RRB. The experimental results indicate that the novel RRB system is able to degrade pyridine with removal efficiency of more than 90%, up to a loading of 250 g/m³/h. The reactor has been in operation for the past 15 months and no loss of activity has been observed.

Flaws developed during the polymerization of composites cause weakness in the final product with a decrease in the value of its mechanical properties [dimetral tensile strength (DTS)]. Therefore, reducing the flaws within the material may improve its mechanical performance. The aim of this study is to determine the effect of polymerization under pressure on the indirect tensile mechanical properties (stiffness and DTS) of light polymerized composite. As composite is a brittle material and failure occurs because of low resistance to tensile stresses, comparison between materials and their failure probability should be based on tensile properties. A special mold is prepared that enables polymerization under pressure. Stiffness (N/mm) and DTS (MPa) are analysed while loading the specimen to failure with an Instron testing machine. Thus, the effect of polymerization under pressure on properties is studied.

The Green function for a spinless charged particle in the presence of an external plane-wave electromagnetic field is calculated by algebraic techniques in terms of the free-particle Green function.

We present an alternative way of using the ξ-function method to calculate the function determinant of an oscillator-type operator with both periodic and Dirichlet boundary conditions. We do it in physical examples and also discuss some fundamental differences between this method and Feynman’s path integral approach. Final comments are made when we do not know the eigenvalues explicitly.

We propose that thed-d fusion rate in palladium can be enhanced by the combined screening of the electrostatic interactions by the itinerant deuterons and the conduction electrons. The model assumes that, under certain conditions, deuterium exists as a D+ ion in palladium. The combined screening by electrons and the D+ ions (deuterons) is found to be more effective than that due to electrons alone. The calculated values of thed-d fusion rates, considering screening, for composition PdD at 300 K are 10−16 s−1 and 10−14 s−1 for D 2 + ion and D2 molecule respectively. These values lie in the range suggested by the recent electrochemical experiments.

The effects of impurities on the transformation pressure and the reaction kinetics of α → ω transformation in Ti metal were studied by the electrical resistivity technique upto a pressure of 80 kbar. The ω-start pressure is found to be lowered when the soaking time was varied from 3 to 10 min. Under identical (viz. 10 min) soaking conditions, the ω-start pressure varied from 29 to 60 kbar, following the increase in oxygen content and other impurity levels in the samples. After the onset of ω, the increase in electrical resistance with time under isothermal-isobaric conditions is typical of that of an isothermal martensite.

The electrical resistivity of compounds having compositions LaSr2Nb x ,O y LaSrNb x O y , and La2SrNb x O y , prepared by arc melting under argon atmosphere, is determined from 77 to 300 K. Low resistivity compositions are found in these systems for x > 2 and niobium in divalent state. None of the compounds investigated showed large resistance drop reported by Oguchi et al. (1987) in La-Sr-Cu-O compounds prepared by sputtering La2CuO4 on niobium substrate and attributed to possible superconductivity about 250 K.

Five systemic organophosphorus insecticides were tested for their intrinsic toxicity in laboratory and persistence of their field-weathered deposits following spray onsarson crop (Brassica campestris L., var.sarson Prain) at recommended concentrations against mustard aphidHyadaphis erysimi (Kalt.). Phosphamidon and demeton-S-methyl proved to be sufficiently toxic compounds and provided protection to the crop for more than 3 days. Thiometon compared to dimethoate was a less toxic insecticide but relatively more persistent. Formothion was found to be the least toxic and least persistent insecticide.

It is shown that relaxions can be formed in a solid at temperature T ≧ TSCHA. (= TEB). Lattice theory of polymer solutions is applied to a solid having two types of atoms — localized atoms and relaxion atoms. The relaxion instability temperature is found to be smaller than TEB. The relaxion model and energy balance criterion together lead to the conclusion that at TEB the solid transforms into a relaxion liquid, i.e., Tm = TEB. The model is (i) in agreement with the Lindemann equation of melting, (ii) explains qualitatively the increase in entropy at melting, and (iii) shows why a solid cannot be superheated above TEB (= Tm), but the liquid can be supercooled to TR (< Tm). Es wird gezeigt, das sich im Festkorper bei Temperaturen T = TSCHA (= TEB) Relaxionen aus-bilden. Die Gittertheorie von Polymerlosungen wird auf einen Festkorper mit zwei Atomarten — lokalisierte Atome und Relaxionsatome — angewendet. Es wird gefunden, das die Relaxions-instabilitatstemperature kleiner als TEB ist. Das Relaxionsmodell zusammen mit dem Energie-bilanzkriterium fuhrt zu dem Schlus, das bei TEB der Festkorper in eine Relaxionsflussigkeit ubergeht, d. h. Tm = TEB. Das Modell ist 1. in Ubereinstimmung mit der Schmelzgleichung von Lindemann, 2. erklart es qualitativ den Entropieanstieg beim Schmelzen und 3. zeigt es, warum ein Festkorper nicht uber TEB (= Tm) aufgeheizt, jedoch die Flussigkeit auf TR (< Tm) unter-kuhlt werden kann.