Magnetic properties of biogenic selenium nanomaterials

Environmental Science and Pollution Research - Bioreduction of selenium oxyanions to elemental selenium is ubiquitous; elucidating the properties of this biogenic elemental selenium (BioSe) is thus...     

A Note on the Use of Conservation Practices in U.S. Agriculture

This article measures the effect of an increase in productivityattributable to an increase in soil organic carbon associated with theincrease in the use of conservation practices in agriculture in theUnited States. Both the direct and indirect effects are calibrated. Theanalytical approach used consists of a dynamic computable generalequilibrium model composed of 14 producing sectors, 10 consumingsectors, seven household categories classified by income, and agovernment. The results suggest that the impact of a change inproductivity is an increase in output over a six year period starting in1998 in field crops. The most significant impact is felt in thelivestock sector. This is because field crops are a major input in theproduction of livestock. The food processing sector also exhibits arelatively large increase because of the increase in inputs of both fieldcrops and livestock. Manufacturing output increases primarily becauseoverall investment rises and most investment utilizes manufacturinggoods. The other producing sectors are generally unaffected by theincrease in agricultural production due to an increase in soil organiccarbon. Coincident with the increase in the production of field cropsis a relatively large decrease in the price of field crops. Othernoticeable price reductions occur in the livestock sector and the foodprocessing sector. For the consuming sectors, the consumption offood and alcohol and tobacco increase but consumption in all of theother sectors remains basically unchanged. Prices in the food andalcohol and tobacco sectors decline by about 1% while theprices in the other sectors remain static. Household welfare increasesin the aggregate by only 0.1% with this increase occurringuniformly across all household categories. Revenue received by thegovernment increases a modest 2% in response to an increase inoutput and, hence, an increase in taxes paid. The results indicate thatthere are significant production benefits for several sectors that can berealized by an increase in the use of conservation practices inagricultural production which, in turn, enhances soil organic carbon.There are a number of policy options available to promote the use ofconservation practices. These include education and technicalassistance, financial assistance, research and development, landretirement, and regulation and taxes.     

Fate of nickel in a lime-stabilized biosolid,a calcareous soil and soil–biosolid mixtures

Soil contamination with anthropogenic metals resulting from biosolid application is widespread around the world. To better predict the environmental fate and mobility of contaminants, it is critical to study the capacity of biosolid-amended soils to retain and release metals. In this paper, nickel adsorption onto a calcareous soil, a lime-stabilized biosolid, and soil–biosolid mixtures (30, 75, and 150 t biosolid/ha) was studied in batch experiments. Sorption experiments showed that (1) Ni adsorption was higher onto the biosolid than the calcareous soil, and (2) biosolid acted as an adsorbent in the biosolid–soil mixtures by increasing Ni retention capacity. The sorption tests were complemented with the estimation of Ni adsorption reversibility by successive applications of extraction solutions with water, calcium (100 mg/L), and oxalic acid (equivalent to 100 mg carbon/L). It has been shown that Ni desorption rates in soil and biosolid-amended soils were lower than 30 % whatever the chemical reagent, indicating that Ni was strongly adsorbed on the different systems. This adsorption/desorption hysteresis effect was particularly significant at the highest biosolid concentration (150 t/ha). Finally, an adsorption empirical model was used to estimate the maximum permissible biosolid application rate using French national guideline. It has been shown that desorption effects should be quantitatively considered to estimate relevant biosolid loadings.     

CCS scenarios optimization by spatial multi-criteria analysis: Application to multiple source sink matching in Hebei province

A method, based on spatial analysis of the different criteria to be taken into consideration for building scenarios of CO₂ capture and storage (CCS), has been developed and applied to real case studies in the Hebei province. Totally 88 point sources (42 from power sector, 9 from iron and steel, 18 from cement, 16 from ammonia, and 3 from oil refinery) are estimated and their total emission amounts to 231.7 MtCO₂/year with power, iron and steel, cement, ammonia and oil refinery sharing 59.13%, 25.03%, 11.44%, 3.5%, and 0.91%, respectively. Storage opportunities can be found in Hebei province, characterised by a strong tectonic subsidence during the Tertiary, with several kilometres of accumulated clastic sediments. Carbon storage potential for 25 hydrocarbon fields selected from the Huabei complex is estimated as 215 MtCO₂ with optimistic assumption that all recovered hydrocarbon could be replaced by an equivalent volume of CO₂ at reservoir conditions. Storage potential for aquifers in the Miocene Guantao formation is estimated as 747 MtCO₂ if closed aquifer assumed or 371 MtCO₂ if open aquifer and single highly permeable horizon assumed. Due to poor knowledge on deep hydrogeology and to pressure increase in aquifer, injecting very high rates requested by the major CO₂ sources (>10 MtCO₂/year) is the main challenge, therefore piezometry and discharge must be carefully controlled. A source sink matching model using ArcGIS software is designed to find the least-cost pathway and to estimate transport route and cost accounting for the additional costs of pipeline construction due to landform and land use. Source sink matching results show that only 15–25% of the emissions estimated for the 88 sources can be sequestrated into the hydrocarbon fields and the aquifers if assuming sinks should be able to accommodate at least 15 years of the emissions of a given source.     

An Air Quality Approach to Natural Gas Curtailment

A natural gas curtailment procedure designed to improve air quality is proposed and discussed. Computer simulations of this approach, in comparison with an approach which ignores environmental factors, shows that the air-quality approach will produce significant improvements in air quality over the non-environmental approach.     

Factors influencing voting by the united states congress on the national energy act

A myriad of factors, both economic and political, influenced the voting by members of the United States Congress on the 1978 National Energy Act. Determinant factors considered in our analysis included the percentage of residents in the Congressman's district residing in the central city or on farms; the percentage of residents who belong to labor unions; the average level of education of the residents; oil, coal, and natural gas production in the state relative to total domestic production. The results, determined by means of logit analysis, indicate that the impact on low-income energy consumers, the effect on overall employment, the impact on farmers, and the benefits to energy interests, as well as ideology and the subjective perception that the need exists to do something about the energy situation in the United States, were all important explanatory factors.The author is an economist with the United States Department of Energy. The views expressed are those of the author and do not necessarily represent the policies of the Department of Energy or the views of other Department of Energy staff members.     

A Spatial equilibrium perspective for planning the production of electrical energy

A spatial and temporal equilibrium model of production, consumption, prices, and transmission is constructed to determine the efficient pricing and allocation of electrical energy in the United States. Regional coordination is technically feasible and economically attractive. It also maximizes environmental efficiencies. The duplication of electrical generation and transmission facilities yields a misallocation of resources.The utilities put forth specific arguments against coordinated operations. Yet in a fully integrated power system, each region would be expected to maximize the benefits of time diversity by purchasing from outside the region in lieu of the expansion of regional capacity. The Federal Energy Regulatory Commission has not yet made a serious move to encourage regional coordination and planning, but the Commission has the authority to promote such operations if it chooses to do so.The author is an economist with the Department of Energy. The views expressed are those of the author and do not necessarily represent the policies of the Department of Energy or the views of other staff members.