9,450 research outputs found
Liberalizing Trade in Environmental Goods
Trade liberalization in environmental goods is high on the agenda of the current Doha round. We examine its effects in a model with one domestic downstream polluting firm and two upstream firms (one domestic, one foreign). The domestic government sets the emission tax rate after the outcome of R&D is known. The upstream firms offer their technologies to the downstream firm at a flat fee. The effect of liberalization on the domestic upstream firm's R&D incentive is ambiguous. Liberalization usually results in cleaner production, which allows the country to reach higher welfare. However this increase in welfare is typically achieved at the expense of the environment (a backfire effect). Thus our results cast doubt on the hoped-for "win-win-win" outcome of trade liberalization in environmental goods.Pollution abatement technology, R&D, trade and environment, trade liberalization, backfire effect
H2S paper strip method - A bacteriological test for faecal coliforms in drinking water at various temperatures
Epidemics arising from waterborne diseases are a global health problem. Faecal contamination of drinking water is the main cause of these outbreaks. According to WHO (1996) for drinking water to be safe, a 100 ml sample should not contain any coliform bacteria. The standard methods currently used for routine testing have many limitations especially when applied in remote areas. The H2S method has been developed as an on-site, inexpensive and easy to use method to test drinking water for remote and rural areas. The present work analyses the reliability of the H2S method for detecting faecal contamination in drinking water. The minimum level of faecal coliforms that could be detected and the incubation period required at various levels of contamination were studied. The range of temperatures at which the method was effective and the incubation period required at various temperatures were also determined. The H2S method was found to be able to detect contamination down to a level of 1 CFU/100 ml of coliform bacteria. Although the H2S method could be used at a temperature range of 20 to 44oC, temperatures between 28 to 37oC gave faster results. An incubation period of only 24 hours was required at 37oC, which was found to be the most suitable incubation temperature. The incubation period increased with a decrease or increase in temperature
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Radial evolution of sunward strahl electrons in the inner heliosphere
The heliospheric magnetic field (HMF) exhibits local inversions, in which the field apparently “bends back” upon itself. Candidate mechanisms to produce these inversions include various configurations of upstream interchange reconnection; either in the heliosphere, or in the corona where the solar wind is formed. Explaining the source of these inversions, and how they evolve in time and space, is thus an important step towards explaining the origins of the solar wind. Inverted heliospheric magnetic field lines can be identified by the anomalous sunward (i.e. inward) streaming of the typically anti-sunward propagating, field aligned (or anti-aligned), beam of electrons known as the “strahl”. We test if the pitch angle distribution (PAD) properties of sunward-propagating strahl are different from those of outward strahl.We perform a statistical study of strahl observed by the Helios spacecraft, over heliocentric distances spanning ≈ 0.3 – 1 AU. We find that sunward strahl PADs are broader and less intense than their outward directed counterparts; particularly at distances 0.3 – 0.75 AU. This is consistent with sunward strahl being subject to additional, path-length dependent, scattering in comparison to outward strahl.We conclude that the longer and more variable path from the Sun to the spacecraft, along inverted magnetic field, leads to this additional scattering. The results also suggest that the relative importance of scattering along this additional path length drops off with heliocentric distance. These results can be explained by a relatively simple, constant-rate, scattering process
Structure and lattice dynamics of the wide band gap semiconductors MgSiN and MgGeN
We have determined the structural and lattice dynamical properties of the
orthorhombic, wide band gap semiconductors MgSiN and MgGeN using
density functional theory. In addition, we present structural properties and
Raman spectra of a MgSiN powder. The structural properties and lattice
dynamics of the orthorhombic systems are compared to wurtzite AlN. We find
clear differences in the lattice dynamics between MgSiN, MgGeN and
AlN, for example we find that the highest phonon frequency in MgSiN is
about 100~cm higher than the highest frequency in AlN and that
MgGeN is much softer. We also provide the Born effective charge tensors
and dielectric tensors of MgSiN, MgGeN and AlN. Phonon related
thermodynamic properties, such as the heat capacity and entropy, are in very
good agreement with available experimental results.Comment: 9 pages, 11 figures, 6 table
Growth of staghorn coral Acropora aspera (Dana) (Scleractinia: Acropridae) in relation to environmental factors at Kavaratti atoll (Lakshadweep Islands), India
Skeletal extension and calcification were measured over 2 years in branches of the staghorn coral
Acropora aspera from a shallow-water si te. Correlations were made between growth parameters and
environmental variables monitored over the same period. Calcification .varied significal)tly (9.4- 17.4
mg. 28d - ') than skeletal extension (3.1 -4.7 mm. 28d -') and unlike extension, it varied significantly between
seasons with lowest values during southwest monsoon (June-September). Seasonal reduction in
calcification was probably associated with the reduced availability oflight due to increased cloud cover and
sediments in water. Extension, however, seemed to be under the direct influence of currents and sediments.
The effect of environmen tal factors seemed more critical to calcification
Skeletal extension of staghorn coral Acropora formosa in relation to environment at Kavaratti atoll (Lakshadweep)
Growth study for 2 years, in rspect of skeletal extension, was conducted in situ at Kavaratti atoll. Average
annual rate of extension of branches was 7.9 ± 2 cm for first year and 8.2 ± 1.8 em for second year. Growth of
individual branches exhibited intracolony variations. Monthly rate of growth was found to be slower during
monsoon (June-September) when compared to premonsoon (February-May) .and postmonsoon
(October-January) seasons. Environmental conditions at the study area, with the exceptIOn of the amount of
sediments in water, seemed conducive to the growth of Acropora formosa
Managing human resource management tensions in project-based organisations: evidence from Bangalore
The article analyses the methods used by a large Indian software company to manage HRM tensions with arising from its activities as a project based organisation. These measures are found to be only partially successful
The evolution of inverted magnetic fields through the inner heliosphere
Local inversions are often observed in the heliospheric magnetic field (HMF), but their origins and evolution are not yet fully understood.Parker Solar Probe has recently observed rapid, Alfvénic, HMF inversions in the inner heliosphere, known as ‘switchbacks’, which have been interpreted as the possible remnants of coronal jets. It has also been suggested that inverted HMF may be produced by near-Sun interchange reconnection; a key process in mechanisms proposed for slow solar wind release. These cases suggest that the source of inverted HMF is near the Sun, and it follows that these inversions would gradually decay and straighten as they propagate out through the heliosphere. Alternatively, HMF inversions could form during solar wind transit, through phenomena such velocity shears, draping over ejecta, or waves and turbulence. Such processes are expected to lead to a qualitatively radial evolution of inverted HMF structures. Using Helios measurements spanning 0.3–1 AU, we examine the occurrence rate of inverted HMF, as well as other magnetic field morphologies, as a function of radial distance r, and find that it continually increases. This trend may be explained by inverted HMF observed between 0.3–1 AU being primarily driven by one or more of the above in-transit processes, rather than created at the Sun. We make suggestions as to the relative importance of these different processes based on the evolution of the magnetic field properties associated with inverted HMF. We also explore alternative explanations outside of our suggested driving processes which may lead to the observed trend
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