Practical environmental monitoring of major construction projects

Independent teams undertook environmental monitoring of particular concentrations of major construction projects forming part of Hong Kong’s U.S. $20 billion airport infrastructure programme located in dense urban areas. The team combination of environmental specialists with experienced civil engineers enabled pragmatic mitigation measures to be developed and accepted by the construction personnel with the result that potentially significant adverse impacts were averted. The authors discuss the mechanism and success of this innovative approach.     

Hydrogen storage and distribution systems

Hydrogen storage and transportation or distribution is closely linked together. Hydrogen can be distributed continuously in pipelines or batch wise by ships, trucks, railway or airplanes. All batch transportation requires a storage system but also pipelines can be used as pressure storage system. Hydrogen exhibits the highest heating value per weight of all chemical fuels. Furthermore, hydrogen is regenerative and environment friendly. There are two reasons why hydrogen is not the major fuel of toady’s energy consumption: First of all, hydrogen is just an energy carrier. And, although it is the most abundant element in the universe, it has to be produced, since on earth it only occurs in the form of water. This implies that we have to pay for this energy, which results in a difficult economic task, because since the industrialization we are used to consuming energy for free. The second difficulty with hydrogen as an energy carrier is the low critical temperature of 33 K, i.e. hydrogen is a gas at room temperature. For mobile and in many cases also for stationary applications the volumetric and gravimetric density of hydrogen in a storage system is crucial. Hydrogen can be stored by six different methods and phenomena: high pressure gas cylinders (up to 800 bar), liquid hydrogen in cryogenic tanks (at 21 K), adsorbed hydrogen on materials with a large specific surface area (at T < 100 K), absorbed on interstitial sites in a host metal (at ambient pressure and temperature), chemically bond in covalent and ionic compounds (at ambient pressure), oxidation of reactive metals e.g. Li, Na, Mg, Al, Zn with water. These metals easily react with water to the corresponding hydroxide and liberate the hydrogen from the water. Finally, the metal hydroxides can be thermally reduced to the metals in a solar furnace.     

TAXING NATURAL RESOURCE PROJECTS

A wide range of fiscal measures for natural resource based projects are analyzed in this paper. Maximizing government revenue involves taxing heavily any rents generated in the project while retaining the incentive to invest. Recovery efficiency must also be preserved. Based upon the principles of resource economics and project appraisai a series of tests are derived and applied to alternative tax schemes in order to assess their efficiency in maximizing the present value of government revenues. The tests indicate that of the ten schemes examined, the most likely to achieve revenue maximization is a progressive resource rent tax incorporating a safeguard tapering provision and superimposed upon normal corporate income tax. Many commonly applied taxes are demonstrated to have serious distortionary effects on the investment decision and to fail to capture a large proportion of rents generated. Cet article analyse une gamme variée de mesures fiscales applicables aux projets concernant les ressources naturelles. L'optimisation des recettes de l'Etat implique une lourde imposition des revenus provenant du projet tout en continuant à encourager les investissements. L'efficacité de la relance doit aussi être maintenue. Sur la base des principes de l'économie des ressources et de l'évaluation des projets, une série de tests a été conçue et appliquée à des systèmes fiscaux alternatifs afin de permettre l'évaluation de leur efficacité en ce qui concerne l'optimisation de la valeur actuelle des recettes de l'Etat. Les tests indiquent que sur les dix systèmes examinés, le plus susceptible d'optimiser les recettes semble être un impôt progressif sur les revenus provenant des ressources qui incorpore une clause de garantie dégressive et qui vient s'ajouter à l'impôt sur le revenu des sociétés habituel. L'article démontre que de nombreux impôts habituellement appliqués présentent de sérieux effets de distortion ayant un impact sur la décision d'investir et qu'une grande proportion des revenus de ces projets échappe à l'imposition. En este artículo se analiza una gama amplia de medidas fiscales sobre proyectos relacionados con recursos naturales. Maximizar los ingresos fiscales requiere imponer fuertes impuestos sobre las rentas generadas por el proyecto manteniendo al mismo tiempo el incentivo para la inversión. Debe mantenerse también la eficiencia en la recuperación de los recursos en cuestión. Basado en principios de la economía de recursos y de evaluación de proyectos se derivan una serie de pruebas sobre esquemas alternativos de aplicación de impuestos con el objeto de evaluar la eficiencia de dichos esquemas en la maximización del valor presente del ingreso del gobierno por concepto de impuestos. Las pruebas indican que de los diez esquemas examinados, el que con mayor probabilidad va a maximizar el ingreso del gobierno es el impuesto progresivo sobre la renta del recurso con un provisión de salvaguarda la reducción de dicho impuesto, más un impuesto simultáneo sobre el ingreso de la empresa. Muchos de los esquemas de imposición comúnmente aplicados tienen serios efectos distortionadores sobre las decisiones de inversión y consecuentamente impiden la colección de una gran parte de las rentas generadas.     

Alteration in Rhizosphere Soil Properties of Afforested <Emphasis Type="Italic">Rhamnus lycioides</Emphasis> Seedlings in Short-Term Response to Mycorrhizal Inoculation with <Emphasis Type="Italic">Glomus intraradices</Emphasis> and Organic Amendment

The reestablisment of autochthonous plant species is an essential strategy for recovering degraded areas under semiarid conditions. A field experiment was carried out to assess the short-term effect of two reafforestation methods involving mycorrhizal inoculation and compost addition on soil quality parameters and Rhamnus lycioides seedling growth. The nutrient content (NPK) and enzymatic activities (dehydrogenase, urease, protease-BAA, acid phosphatase and β-glucosidase) increased and bulk density decreased in the rhizosphere soil with the organic amendment. Biomass C of rhizosphere soil increased by at least 240% with respect to the control soil after mycorrhizal inoculation and the combination of compost addition + mycorrhizal inoculation. Both mycorrhizal inoculation and composted organic residue addition increased R. lycioides seedling growth in the same proportion. In the short term, we conclude that the application of both reafforestation methods not only enhances the establishment of R. lycioides seedlings, but also improves soil quality.     

MODELING THE IMPACT OF MULTICOMPONENT VOCs ON GROUND WATER USING THE STEFAN‐MAXWELL EQUATION1

ABSTRACT: Computer programs that model the fate and transport of organic contaminants through porous media typically use Fick's first law to calculate vapor phase diffusion. Fick's first law, however, is limited to the case of a single, dilute species diffusing into a stagnant, high concentration, bulk vapor phase. When dealing with more than one diffusing species and at higher concentrations, the multicomponent coupling effects on vapor phase diffusion and advection of the various constituents become significant. VLEACH, a one‐dimensional finite difference model developed for the U.S. Environmental Protection Agency (USEPA), is typical of the models using Fick's first law to model vapor‐phase diffusion. The VLEACH model was modified to accommodate up to 10 components and to calculate the binary diffusion coefficients for each of the components based on molecular weight, molecular volume, temperature and pressure, and to address the coupling effects on multiple component vapor phase diffusion and its impact on ground water. The resulting model was renamed MC‐CHEMSOIL. At low vapor phase concentrations, MC‐CHEMSOIL predicts identical ground water impacts (dissolved phase loading) to those from VLEACH 2.2a. At higher vapor phase concentrations, however, the relative difference between the models exceeded 20 percent.     

Facile Preparation of Chitosan Films for High Performance Removal of Reactive Blue 19 Dye from Aqueous Solution

This study aimed at finding effective strategies for high-performance removal of reactive blue 19 (RB19) dye from aqueous solution. Chitosan (CS) films had been prepared by using solvent casting with mild drying for this purpose. The CS films were characterized by X-ray diffraction, field-emission scanning electron microscopy, and Fourier transform infrared (FTIR) spectroscopy. The performance of RB19 removal using CS were evaluated by varying contact time, solution pH, initial dye concentration, and adsorbent dosage. Adsorption isotherms, kinetics, and desorption were investigated by batch experiments. Results showed that CS films exhibited the optimal adsorption performance for RB19 removal and high maximum adsorption capacities of RB19, which were 799 and 822.4 mg g^?1 at 20 and 40 °C, respectively. Adsorption kinetic data were well described by the pseudo-second-order kinetic model. FTIR analyses further indicated that interactions between RB19 and the CS film occurred during adsorption. The CS films also exhibited satisfactory desorption of RB19 at about 80 % after 30 min of desorption at pH 11. Our study demonstrated that the CS films can be easily prepared and applied for effective removal of RB19 in treatment of wastewater.     

Report on the fifth meeting of INRA’s national network of ecotoxicologists,ECOTOX

The fifth meeting of INRA’s national network of ecotoxicologists took place on 25 to 27 November 2014 in Biarritz, France. The main aim of the meeting was to bring together ecotoxicologists from INRA and associated partners, providing them ample opportunity to share and discuss their latest scientific results as well as the national policy of research in ecotoxicology and to precise perspectives for the network.