Watershed development: A solution to water shortages in semi-arid India or part of the problem?

There have been dramatic changes in the hydrology of many of the dry areas of South India in recent years as a result of increased groundwater-based irrigation, watershed development and land use change. Although intensive development of water resources has brought about huge benefits, its very success has thrown up new challenges. Demand and competition for water has increased to the extent that — in some areas — current levels of annual water use are so high that, in all but the wettest years, annual water use approximates towards annual replenishment of surface and ground water resources. In these areas, it is clear that the emphasis should switch from development to the management of water resources to ensure that water is allocated to activities with the highest economic and social value. Although current watershed development programmes bring a range of benefits, they may also change the temporal and spatial pattern of water availability and use. This can result in significant negative trade-offs such as more unreliable domestic water supplies in ‘downstream’ areas, particularly during low rainfall or drought years. As part of the Karnataka Watershed Development Project (KAWAD), a water resource audit assessed the status of water resources in the project watersheds and identified resource management practices that should be promoted by the project. This paper summarises the audit’s findings and recommendations, the main lessons learned and progress to date in implementing recommendations. For comparison, findings and recommendations from a water audit in southern Andhra Pradesh are also summarised.Resource /Energy Economics and Policy,

Evaluation of electrode-semiconductor barrier in transparent top-contact polymer field effect

Interfacial barriers at the metal- semiconductor junction manifest in the form of sizable contact resistance in polymer field effect transistors (PFETs). We study the barrier using optical excitation directed specifically beneath the electrodes in the top- contact PFETs without optically perturbing the channel. Differences in the transconductance responses with the light localized at the source and the drain electrode region provides a considerable insight into the injection barriers

Planning of Ventilation Requirements for Deep Mechanised Long Wall Faces – A Case Study of Adriyala Longwall Project of The Singareni Collieries Company Limited (SCCL)

AbstractWith near exhaustion of shallow deposits, mining operations are planned to reach greater depths. Coal mining particularly in SCCL has to face numerous challenges for extraction from lower horizons associated with difficult geo-mining and environmental conditions. Suitable mining technology with heavy mechanisation is being introduced to meet the production requirements safely and economically. Mining at greater depth needs strategic planning and execution to overcome the operational problems and issues related to mine environment. AdriyalaLongwall Project in SCCL is planned to operate with high capacity Longwall unit at depth range of 300-720m. To maintain comfort work place environment in workings of the mine, it is proposed to establish suitable ventilation system along with air cooling arrangements. This paper gives insight of the details of the project and ventilation system executed to meet the requirements and the proposed air cooling arrangements at the mine

Selection of optimum combination of fans for bord and pillar coal mines - A Case Study

A good design of ventilation system for a mine should supply adequate air flow for all workings. One of the objectives of the ventilation planning is to select optimum operating points for the fan and its combinations to achieve the required air flow rate. It will improve the safety conditions and minimise the total air power consumption. The objective of this study is to increase ventilation quantity with low operating pressure and effective utilisation of the main mechanical ventilator. Ventilation simulator and CFD modelling studies were conducted with different combinations of fans. Operating parallel fans with the same capacity and blade angle at the return air shaft is the best possible solution for achieving this objective. A detailed case study of the pressure survey of the ventilation network and the simulation results is presented

Purification, physicochemical and regulatory properties of serine hydroxymethyltransferase from sheep liver

Serine hydroxymethyltransferase (EC 2.1.2.1) was purified from the cytosolic fraction of sheep liver by ammonium sulphate fractionation, CM-Sephadex chromatography, gel filtration using Ultrogel ACA 34 and Blue Sepharose affinity chromatography. The homogeneity of the enzyme was rigorously established by Polyacrylamide gel and sodium dodecyl sulphate-polyacrylamide gel electrophoresis, isoelectrofocusing, ultracentrifugation, immunodiffusion and Immunoelectrophoresis. The enzyme was a homotetramer with a molecular weight of 210,000 ± 5000. The enzyme showed homotropic cooperative interactions with tetrahydrofolate (nH = 2.8) and a hyperbolic saturation pattern with L-serine. At the lowest concentration of tetrahydrofolate used (0.2 mM), only 5% of the added folate was oxidized during preincubation and assay. ThenH value was independent of the time of preincubation. Preincubation of the enzyme with serine resulted in a partial loss of the cooperative interactions (nH =1.6) with tetrahydrofolate. The enzyme was regulated allosterically by interaction with nicotinamide nucleotides; NADH was a positive effector while NAD+ was a negative allosteric effector. The subunit interactions were retained even at the temperature optimum of 60‡C unlike in the case of the monkey liver enzyme, where these interactions were absent at higher temperatures. D-Cycloserine, a structural analogue of serine caused a sigmoid pattern of inhibition, in contrast with the observations on the monkey liver enzyme. Cibacron blue F3GA completely inhibited the enzyme and this inhibition could be reversed by tetrahydrofolate. Unlike in the monkey liver enzyme, NAD+ and NADH gave considerable protection against this inhibition. The sheep liver enzyme differs significantly in its kinetic and regulatory properties from the serine hydroxymethyltransferases isolated from other sources

Optimization of Loss Minimization Using FACTS in Deregulated Power Systems

Losses are an important parameter of consideration for mitigation and thereby enhancing the Available Transfer Capability of Power Systems. Loss mitigation is a two stage process the first stage is the Planning phase and the second stage is the Operational phase. The paper discusses briefly the Planning phase activities. The various methods of mitigating the losses in the Operational phase have been presented in the paper with emphasis on one technique the Flexible Alternating Current Transmission System devices. The Flexible Alternating Current Transmission System Devices are the latest power electronics devices by which losses can be reduced and transfer capability enhanced. Thyristor Control Series Compensator is used to reduce losses. The method is tested on IEEE 9 bus, 14 Bus and 30 bus systems and validated. Results have been presented and analyzed in this paper. Keywords: Available Transfer Capability, B- Loss Coefficients, Flexible Alternating Current Transmission Systems, Thyristor Controlled Series Compensator

Modelling , of Polyurethanes Based on Hydroxyl- Terminated Polybutadiene

Forty formulations based on four different grades ofhydroxyl-terminated polybutadiene, HTPB(hydroxyl value 20- 40 mg KOHlg) at r = [NCO] / [OH] values in the range 0.7 -1.0 with varyingamounts of trimethylol propane and butane diol and containing 86 per cent solid loading wereconsidered to test the applicability of a.-model of Marsh, et al. for prediction of the mechanicalproperties of composite solid propellants. Two network parameters, crosslink density (Ve) andeffective chain length (LX), were calculated from the model. Tensile strength and modulus werecorrelated to Ve and elongation at break to LX. Using the correlations obtained from experimental dataat r< 0.8, mechanical properties of the various fonnulations were predicted. Good agreement betweenexperimental and predicted properties was obtained for fonnulations with modulus 10 KSC. Probablereasons for deviation observed at stoichiometric ratio r < 0.8 and low modulus values are discussed.Improved correlations between mechanical properties and network parameters, applicable over a widerange of fonnulations, were arrived at. The standard errors of prediction were found to be close to :+- 1 0-value of the measurement

Control of single-wall-nanotube field-effect transistors via indirect long-range optically induced processes

We observe significant changes in the response of single-wall-carbon-nanotube-based field-effect transistors upon photoexcitation in the presence of optically active conjugated polymer network. The primary features observed are in the form of an increase in the current in the depletion mode upon photoexcitation. Pulsed measurements indicate that the transistor enters the depleted state prior to the rise in current brought about by the transfer of the photogenerated carriers from the semiconducting polymer to the nanotube under depletion bias

Synthesis of some 3-(2-substituted sulfanyl-imidazo [2,1-b][1,3,4] thiadiazol-6-yl)-chromen-2-one and its derivatives

454-458A series of 3-(2-substituted sulfanyl-imidazo [2,1-b][1,3,4] thiadiazol-6-yl)-chromen-2-ones (3) have been synthesized from 3-(2-bromo acetyl) chromen-2-ones 1 and 2-amino-5-thio substituted[1,3,4]thiadiazole 2 in anhydrous ethanol. The 7,8-benzo analogs of 3-(2-substituted sulfanyl-imidazo[2,1-b][1,3,4] thiadiazol-6-yl)-chromen-2-ones 5 have been synthesized under similar conditions. All the synthesized compounds have been characteriszed by analytical and spectral data

Object-oriented language for the report specification interface to a case repository

Computer Scienc