From an open-access to a state-controlled resource: the case of groundwater in the Kathmandu Valley,Nepal

Groundwater is no longer an open-access resource in Kathmandu. Perceptions of groundwater are changing from an “infinite” to a “finite” resource and the role of the government from supply developer to caretaker of the resource. In this context, this paper aims to unfold how perceptions of groundwater in Kathmandu Valley, Nepal, are changing from an open-access resource to an overexploited, depleted, degraded, vulnerable and state-controlled resource. In the process, it produces an aggregated picture of resource availability, development dynamics, impacts and responses in the area; suggests some “soft-path” approaches for groundwater management; and discusses implications of the experience for other areas.     

Drought,distress, and a conditional cash transfer programme to mitigate the impact of drought in Bihar,India

Paddy – Bihar’s staple crop – is vulnerable to drought, primarily due to the high cost of irrigation. In 2008, the Bihar government launched a conditional cash transfer scheme to subsidize diesel for irrigation in drought-affected areas. We show that this scheme has not been effective in mitigating the impact of drought on paddy production. A primary survey of potential and actual beneficiaries shows that low awareness and penetration among smallholders, alongside uncertainties and delays in the disbursal of the subsidy, make it ineffective. We suggest that in states with limited capacity, such ad hoc subsidies are unlikely to protect smallholders from weather shocks.     

A New Model for Simulating Supplemental Irrigation and the Hydro-Economic Potential of a Rainwater Harvesting System in Humid Subtropical Climates

Here we have developed a new model to simulate supplemental irrigation and the hydro-economic potential of a rainwater harvesting system in rainfed agricultural areas. Using the model, soil moisture in rainfed crop land, supplemental irrigation requirements, rainwater storage in an on-farm reservoir (OFR) system, and surface and ground water availability were predicted. In an irrigated system, an OFR was used to harvest rainwater during the rainy season, and stored water was applied to cropland as supplemental irrigation (SI). An economic analysis was performed to calculate the benefits due to an OFR irrigation system, and gains from increased crop yield and downstream water availability in the irrigated OFR system were compared with rainfed system (i.e. no OFR). In addition, we calculated the impacts of dry and wet seasons on total value gains (grain and water gains) for irrigated and rainfed conditions and performed a sensitivity analysis to quantify the impacts of model input parameters on total value gains. Analyses showed that the OFR system can produce crop yields three times greater than rainfed agriculture. During a water stress season, the total water use in the irrigated system was 65 % greater than for the rainfed system. Water use efficiency of the irrigated system was 82 % higher than for the rainfed system. In a dry season, the total value gains due to increased crop yield by supplemental irrigation and downstream water availability of the irrigated system were 74 % greater than for the rainfed system, while in a wet season the total value gain of the irrigated system was 14 % greater than for the rainfed system. A precipitation scenario analysis of wet and dry seasons indicated that the benefits of a rainwater harvesting system can be considerably greater in dry seasons than wet seasons.     

Medieval bronzes of the Himalayan Mountain Kingdoms

Over the last quarter-century, there has been a discernible increase in the number of scholars who have focused their research on metal production, working, and use in antiquity, afield of study which has come to be known as Archaeometallurgy. Materials scientists and conservators have worked primarily in the laboratory while archaeologists have conducted fieldwork geared to the study of metal technology in a cultural context with laboratory analysis as one portion of the interpretive program.     

Effect of strain rate on sigma formation in ferrite-austenite stainless steel at high temperatures

Sigma precipitation in an Fe-19Cr-5Ni-2.7Mo ferrite -austenite duplex stainless steel has been investigated during and after uniaxial compression at 900° C. At this temperature ferrite and austenite phases are present in equivolume proportions (1:1 ). It was found that sigma precipitation was enhanced by hot working and the volume proportion of sigma decreased as the straining rate increased. Sigma nucleated at ferrite-austenite interfaces and grew into ferrite grains by the eutectoid reaction + . Transmission electron microscopy revealed that large sigma particles enhanced recrystallization of the austenite phase in duplex structures at high temperature.     

Proton conducting polymer electrolyte: II poly ethylene oxide + NH4l system

A new proton conducting polymer electrolyte PEO + NH₄l system has been investigated. The solution-cast films of different stochiometric ratios have been prepared and characterized. Proton transport has been established using various experimental studies, namely optical microscopy, X-ray diffraction, differential thermal analysis, infrared, coulometry transient ionic current and electrical conductivity measurements at different temperatures and humidity. The maximum conductivity of the complexed material has been found to be 10^–5 S cm^–1. Both H⁺ ion and I^– anion movements are involved with respective transference numbers and mobilities ast _H+=0.74, ,t _l–=0.09, _H+=4.97 × 10^–6 cm² V^–1 s^–1 and _l–=7.65.     

Effect of Primary Silicon Refinement on Mechanical and Wear Properties of a Hypereutectic Al-Si Alloy

Silicon - This study explores the effect of primary silicon refinement of hypereutectic Al-Si alloy on the mechanical and wear properties. Refinement has been carried out by purging N2 into...