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Sample records for aluminum reduction plant

  1. 77 FR 2677 - National Emission Standards for Hazardous Air Pollutants: Primary Aluminum Reduction Plants...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-19

    ... Aluminum Reduction Plants; Extension of Comment Period AGENCY: Environmental Protection Agency (EPA... Standards for Hazardous Air Pollutants: Primary Aluminum Reduction Plants'' is being extended for 12 days...

  2. Cancer Risks in Aluminum Reduction Plant Workers

    PubMed Central

    Labrèche, France

    2014-01-01

    Objective and Methods: This review examines epidemiological evidence relating to cancers in the primary aluminum industry where most of what is known relates to Söderberg operations or to mixed Söderberg/prebake operations. Results and Conclusions: Increased lung and bladder cancer risks have been reported in Söderberg workers from several countries, but not in all. After adjustment for smoking, these cancer risks still increase with cumulative exposure to benzo(a)pyrene, used as an index of coal tar pitch volatiles exposure. Limited evidence has been gathered in several cohorts for an increased risk of tumors at other sites, including stomach, pancreas, rectum/rectosigmoid junction, larynx, buccal cavity/pharynx, kidney, brain/nervous system, prostate, and lymphatic/hematopoietic tissues (in particular non-Hodgkin lymphoma, Hodgkin disease, and leukemia). Nevertheless, for most of these tumor sites, the relationship with specific exposures has not been demonstrated clearly and further follow-up of workers is warranted. PMID:24806725

  3. Altered immune status in aluminum reduction plant workers

    SciTech Connect

    Davis, R.L.; Milham, S. Jr. )

    1990-01-01

    From 1978 to 1985, B-cell lymphoma occurred in five employees of an aluminum reduction plant (expected = 0.2; Poisson distribution). As immunodeficiency is a known risk factor for B-cell lymphoma, we did a pilot study to evaluate immune function in apparently healthy plant workers. Twenty-three volunteers were selected for study from 350 workers, representing a range of experience in the potroom and with exposures to strong magnetic fields and volatilized aromatic hydrocarbons. Potroom workers had significantly higher T8 levels (mean = 1,227) than non-potroom workers (mean = 597) (p less than .05, Wilcoxon rank sums) or established normal values (median = 450). T4 levels were higher for potroom workers (mean = 1,017) than for non-potroom workers (mean = 558) or for established norms (median = 756) (p less than .10, Wilcoxon rank sums). Ten of 20 potroom workers had abnormal T4/T8 ratios (less than 0.91) due to disproportionate elevation of the T8 subpopulation. These data suggest an underlying immune alteration in the aluminum workers studied. Further study is needed to assess the implications of abnormal T-cell subsets in a worker population with high rates of lymphoma.

  4. Mortality and cancer incidence in aluminum reduction plant workers

    SciTech Connect

    Spinelli, J.J.; Band, P.R.; Svirchev, L.M.; Gallagher, R.P. )

    1991-11-01

    An historical cohort study was conducted among 4,213 men who worked for 5 or more years at a Soderberg aluminum reduction plant in British Columbia (BC), Canada. Standardized mortality and incidence ratios were used to compare the mortality and cancer incidence of the cohort with that of the BC population and to examine risk by cumulative exposure to coal-tar pitch volatiles (CTPV) and electromagnetic fields. Significantly elevated rates were observed for bladder cancer incidence (standardized incidence ratio (SIR) = 1.69) and brain cancer mortality (standardized mortality ratio = 2.17). The risk of bladder cancer was strongly related to cumulative exposure to CTPV (P less than .01). The risk for non-Hodgkin's lymphoma also increased with increasing exposure (P less than .05), although the overall rate was similar to that of the general population (SIR = 1.06). The lung cancer rate was as expected (SIR = 0.97), but showed a weak association with CTPV exposure that was not statistically significant. No individual cause of death or incident cancer site was related to exposure to electromagnetic fields. Analysis of the joint effect of smoking and CTPV exposure on lung and bladder cancer showed the exposure response relationships to be independent of smoking.

  5. Assessment of geothermal energy as a power source for US aluminum reduction plants

    SciTech Connect

    Enderlin, W.I.; Blahnik, D.E.; Davis, A.E.; Jacobson, J.J.; Schilling, A.H.; Weakley, S.A.

    1980-02-01

    The technical and economic feasibility of using hydrothermal resources as a primary power source for both existing and future aluminum reduction plants in the United States is explored. Applicable hydrothermal resources that should be considered by the aluminum industry for this purpose were identified and evaluated. This work also identified the major institutional parameters to be considered in developing geothermal energy resources for aluminum industry use. Based on the findings of this study, it appears technically and economically feasible to power existing aluminum reduction plants in the Pacific Northwest using electricity generated at Roosevelt Hot Springs, Utah. It may also be feasible to power existing plants located on the Gulf Coast from Roosevelt Hot Springs, depending on the cost of transmitting the power.

  6. Changes in litter near an aluminum reduction plant

    USGS Publications Warehouse

    Beyer, W.N.; Fleming, W.J.; Swineford, D.

    1987-01-01

    Litter was collected from eight sites at distances as far as 33 km from an AI reduction plant in western Tennessee. As a result of an accumulation of fine litter (< 4.75 mm) the weight of the litter per unit area was abnormally high at the two sites within 2 km of the plant. Compared to litter collected far from the plant, it had a lower fiber content, was more sapric, and was less acid. Fluoride emissions from the plant were suggested as the probable cause of litter changes. Concentrations of water-extractable and acid-extractable F- in the litter, the 0- to 5-cm soil layer, and the 5- to 15-cm soil layer were strongly correlated with distance from the plant. Total acid-extractable F- in the litter and upper 15 cm of soil was about 41 times as much at the closest site (700 mg/kg) as at the most distant sites (12 and 16 mg/kg). In a bioassay of litter from our study sites, woodlice (Porcellio scaber Latr.) had an abnormally high mortality in litter that contained 440 mg/kg or more of acid-extractable F-. However, when F- was added as NaF to litter, a significant increase in mortality was observed only in treatments exceeding 800 mg/kg. The decrease in the rate of decomposition of the litter might eventually induce a deficiency of soil macronutrients, but none was detected.

  7. Mortality of aluminum reduction plant workers, 1950 through 1977

    SciTech Connect

    Gibbs, G.W.

    1985-10-01

    The mortality experience of 5,406 men (cohort I) employed at one aluminum smelter on Jan. 1, 1950, and 485 men employed at a second plant (cohort II) on January 1, 1951, is reported. For each man, the total number of years of exposure to tars, the number of years since first exposure to tars, and an index of exposure to tars expressed in tar-years were calculated. More than 99% of the men in the first cohort and 98% of the men in the second cohort were traced. Of the 1539 men in cohort I who were deceased as of December 31, 1977, death certificates were obtained for 1432 (93%). Of the 92 men in cohort II who were deceased as of December 31, 1977, death certificates were obtained for 80 (87%). The results showed that men in cohort I died of the following causes at approximately the same rate as or less frequently than men of similar age in the Province of Quebec: tuberculosis; circulatory disease; hypertensive heart disease; trauma; leukemia and aleukemia; and malignant neoplasms of the pancreas, genital organs, brain, intestine, and rectum and other abdominal areas. There were no deaths from pneumoconiosis or Alzheimer's disease. Although the observed and expected numbers of deaths in some of the cause-of-death categories were small, men in cohort I died of the following causes more frequently than did men of similar age in the Province of Quebec: respiratory disease; pneumonia and bronchitis; malignant neoplasms (all sites); malignant neoplasms of the stomach and esophagus, bladder, and lung; other malignant neoplasms; Hodgkin's disease; and other hypertensive disease. Mortality from malignant neoplasms of the bladder and lung was meaningfully related to numbers of tar-years and of years of exposure. Exposure-response relationships were less clear for malignant neoplasms of the esophagus and stomach and for other malignancies.

  8. Determination of thiaarenes and polycyclic aromatic hydrocarbons in workplace air of an aluminum reduction plant

    SciTech Connect

    Becker, G.; Colmsjoe, A.; Oestman, C.

    1999-05-01

    Quantitation of a variety of tetra-, penta-, and hexacyclic aromatic sulfur heterocycles (thiaarenes) in workplace air of an aluminum reduction plant has been made by help of gas chromatography with atomic emission detection (GC-AED). Personal exposure to those thiaarenes and to polycyclic aromatic hydrocarbons depending on work categories has been evaluated. Summarized concentrations of the thiaarenes investigated have been found to be 0.4--19.0 {micro}g/m{sup 3}. When using sulfur selective AED, samples could be analyzed without a prior separation of the thiaarenes from the PAH. The present data indicate a contribution of thiaarenes to the overall toxicity of coal tar pitch volatiles in this work environment.

  9. 76 FR 76259 - National Emissions Standards for Hazardous Air Pollutants: Primary Aluminum Reduction Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-06

    ...The EPA is proposing amendments to the national emissions standards for hazardous air pollutants for Primary Aluminum Reduction Plants to address the results of the residual risk and technology review that the EPA is required to conduct by the Clean Air Act. If finalized, these proposed amendments would address previously unregulated emissions (i.e., carbonyl sulfide (COS) emissions from new and existing potlines and polycyclic organic matter (POM) emissions from new and existing prebake potlines and existing pitch storage tanks); remove the vertical stud Soderberg one (VSS1) potline subcategory; reduce the MACT limits for POM emissions from horizontal stud Soderberg (HSS) and VSS2 potlines; eliminate the startup, shutdown and malfunction exemption in accordance with recent actions by the United States Court of Appeals for the District of Columbia Circuit; add provisions for facilities to avail themselves of an affirmative defense in the event of a malfunction under certain conditions; and make certain technical and editorial changes. The proposed emissions limits for POM and COS are based on maximum achievable control technology (MACT). While the proposed modifications would result in some reduction in actual emissions of POM from existing pitch storage tanks, reduce the potential emissions of POM from Soderberg potlines, and prevent increases in emissions of COS and sulfur dioxide, the health risks posed by actual emissions from this source category are currently within the acceptable range and would not be reduced appreciably by the proposed modifications.

  10. A Virtual Aluminum Reduction Cell

    NASA Astrophysics Data System (ADS)

    Zhang, Hongliang; Zhou, Chenn Q.; Wu, Bing; Li, Jie

    2013-11-01

    The most important component in the aluminum industry is the aluminum reduction cell; it has received considerable interests and resources to conduct research to improve its productivity and energy efficiency. The current study focused on the integration of numerical simulation data and virtual reality technology to create a scientifically and practically realistic virtual aluminum reduction cell by presenting complex cell structures and physical-chemical phenomena. The multiphysical field simulation models were first built and solved in ANSYS software (ANSYS Inc., Canonsburg, PA, USA). Then, the methodology of combining the simulation results with virtual reality was introduced, and a virtual aluminum reduction cell was created. The demonstration showed that a computer-based world could be created in which people who are not analysis experts can see the detailed cell structure in a context that they can understand easily. With the application of the virtual aluminum reduction cell, even people who are familiar with aluminum reduction cell operations can gain insights that make it possible to understand the root causes of observed problems and plan design changes in much less time.

  11. Electrolyte treatment for aluminum reduction

    DOEpatents

    Brown, Craig W.; Brooks, Richard J.; Frizzle, Patrick B.; Juric, Drago D.

    2002-01-01

    A method of treating an electrolyte for use in the electrolytic reduction of alumina to aluminum employing an anode and a cathode, the alumina dissolved in the electrolyte, the treating improving wetting of the cathode with molten aluminum during electrolysis. The method comprises the steps of providing a molten electrolyte comprised of ALF.sub.3 and at least one salt selected from the group consisting of NaF, KF and LiF, and treating the electrolyte by providing therein 0.004 to 0.2 wt. % of a transition metal or transition metal compound for improved wettability of the cathode with molten aluminum during subsequent electrolysis to reduce alumina to aluminum.

  12. Aluminum reduction cell electrode

    DOEpatents

    Goodnow, Warren H.; Payne, John R.

    1982-01-01

    The invention is directed to cathode modules comprised of refractory hard metal materials, such as TiB.sub.2, for an electrolytic cell for the reduction of alumina wherein the modules may be installed and replaced during operation of the cell and wherein the structure of the cathode modules is such that the refractory hard metal materials are not subjected to externally applied forces or rigid constraints.

  13. Aluminum reduction cell electrode

    DOEpatents

    Goodnow, W.H.; Payne, J.R.

    1982-09-14

    The invention is directed to cathode modules comprised of refractory hard metal materials, such as TiB[sub 2], for an electrolytic cell for the reduction of alumina wherein the modules may be installed and replaced during operation of the cell and wherein the structure of the cathode modules is such that the refractory hard metal materials are not subjected to externally applied forces or rigid constraints. 9 figs.

  14. Aluminum reduction cell electrode

    DOEpatents

    Payne, John R.

    1983-09-20

    The invention is directed to an anode-cathode structure for an electrolytic cell for the reduction of alumina wherein the structure is comprised of a carbon anode assembly which straddles a wedge-shaped refractory hard metal cathode assembly having steeply sloped cathodic surfaces, each cathodic surface being paired in essentially parallel planar relationship with an anode surface. The anode-cathode structure not only takes into account the structural weakness of refractory hard metal materials but also permits the changing of the RHM assembly during operation of the cell. Further, the anode-cathode structure enhances the removal of anode gas from the interpolar gap between the anode and cathode surfaces.

  15. Aluminum reduction cell electrode

    DOEpatents

    Payne, J.R.

    1983-09-20

    The invention is directed to an anode-cathode structure for an electrolytic cell for the reduction of alumina wherein the structure is comprised of a carbon anode assembly which straddles a wedge-shaped refractory hard metal cathode assembly having steeply sloped cathodic surfaces, each cathodic surface being paired in essentially parallel planar relationship with an anode surface. The anode-cathode structure not only takes into account the structural weakness of refractory hard metal materials but also permits the changing of the RHM assembly during operation of the cell. Further, the anode-cathode structure enhances the removal of anode gas from the interpolar gap between the anode and cathode surfaces. 10 figs.

  16. Primary Aluminum Plants Worldwide - 1998

    USGS Publications Warehouse

    1999-01-01

    The 1990 U.S. Bureau of Mines publication, Primary Aluminum Plants Worldwide, has been updated and is now available. The 1998 USGS edition of Primary Aluminum Plants Worldwide is published in two parts. Part I—Detail contains information on individual primary smelter capacity, location, ownership, sources of energy, and other miscellaneous information. Part II—Summary summarizes the capacity data by country

  17. REPORT ON QUALITATIVE VALIDATION EXPERIMENTS USING LITHIUM-ALUMINUM LAYERED DOUBLE-HYDROXIDES FOR THE REDUCTION OF ALUMINUM FROM THE WASTE TREATMENT PLANT FEEDSTOCK

    SciTech Connect

    HUBER HJ; DUNCAN JB; COOKE GA

    2010-05-11

    A process for removing aluminum from tank waste simulants by adding lithium and precipitating Li-Al-dihydroxide (Lithiumhydrotalcite, [LiAl{sub 2}(OH){sub 6}]{sup +}X{sup -}) has been verified. The tests involved a double-shell tank (DST) simulant and a single-shell tank (SST) simulant. In the case of the DST simulant, the product was the anticipated Li-hydrotalcite. For the SST simulant, the product formed was primarily Li-phosphate. However, adding excess Li to the solution did result in the formation of traces of Li-hydrotalcite. The Li-hydrotalcite from the DST supernate was an easily filterable solid. After four water washes the filter cake was a fluffy white material made of < 100 {micro}m particles made of smaller spheres. These spheres are agglomerates of {approx} 5 {micro}m diameter platelets with < 1 {micro}m thickness. Chemical and mineralogical analyses of the filtrate, filter cake, and wash waters indicate a removal of 90+ wt% of the dissolved Al for the DST simulant. For the SST simulant, the main competing reaction to the formation of lithium hydrotalcite appears to be the formation of lithium phosphate. In case of the DST simulant, phosphorus co-precipitated with the hydrotalcite. This would imply the added benefit of the removal of phosphorus along with aluminum in the pre-treatment part of the waste treatment and immobilization plant (WTP). For this endeavor to be successful, a serious effort toward process parameter optimization is necessary. Among the major issues to be addressed are the dependency of the reaction yield on the solution chemistry, as well as residence times, temperatures, and an understanding of particle growth.

  18. Mortality and cancer experience of Quebec aluminum reduction plant workers. Part I: The reduction plants and coal tar pitch volatile (CTPV) exposure assessment

    SciTech Connect

    Lavoue, J.; Gerin, M.; Cote, J.; Lapointe, R.

    2007-09-15

    This paper presents the exposure assessment and job-exposure matrix (JEM) used to estimate coal tar pitch volatile (CTPV) exposure for a study of mortality and cancer incidence in aluminum smelter workers in Quebec, Canada. Historical CTPV exposure was assessed by estimating benzene-soluble material (BSM) and benzo(a)pyrene (B(a)P) levels for combinations of job and time period. Estimates were derived by using several procedures including averaging measurement data, a deterministic mathematical model using process-related correction factors, and expert-based extrapolation. The JEM comprised 28,910 jobs, covering 7 facilities from 1916 to 1999. Estimated exposures ranged from 0.01 {mu} g/m{sup 3} to 68.08 {mu} g/m{sup 3} (B(a)P) and 0.01 mg/m{sup 3} to 3.64 mg/m{sup 3} (BSW) and were lowest before 1940 and after 1980. This methodology constitutes an improvement compared with methods used for previous studies of the Quebec cohort.

  19. The mathematical modeling of aluminum reduction cells

    NASA Astrophysics Data System (ADS)

    Arkhipov, G. V.

    2006-02-01

    In order to expand its primary aluminum capacity, Rusal has focused on improving its technological base. Toward that end, the company created the Engineering and Technological Center (ETC). Within the ETC the Division of Mathematical Modeling was established to enable technical decisions to be made based not only on engineering intuition and practical experience, but also on the calculations of technological processes and constructions. This article describes the ETC's work in the mathematical modeling of aluminum reduction cells.

  20. Progress in Aluminum Electrolysis Control and Future Direction for Smart Aluminum Electrolysis Plant

    NASA Astrophysics Data System (ADS)

    Zhang, Hongliang; Li, Tianshuang; Li, Jie; Yang, Shuai; Zou, Zhong

    2017-02-01

    The industrial aluminum reduction cell is an electrochemistry reactor that operates under high temperatures and highly corrosive conditions. However, these conditions have restricted the measurement of key control parameters, making the control of aluminum reduction cells a difficult problem in the industry. Because aluminum electrolysis control systems have a significant economic influence, substantial research has been conducted on control algorithms, control systems and information systems for aluminum reduction cells. This article first summarizes the development of control systems and then focuses on the progress made since 2000, including alumina concentration control, temperature control and electrolyte molecular ratio control, fault diagnosis, cell condition prediction and control system expansion. Based on these studies, the concept of a smart aluminum electrolysis plant is proposed. The frame construction, key problems and current progress are introduced. Finally, several future directions are discussed.

  1. Progress in Aluminum Electrolysis Control and Future Direction for Smart Aluminum Electrolysis Plant

    NASA Astrophysics Data System (ADS)

    Zhang, Hongliang; Li, Tianshuang; Li, Jie; Yang, Shuai; Zou, Zhong

    2016-10-01

    The industrial aluminum reduction cell is an electrochemistry reactor that operates under high temperatures and highly corrosive conditions. However, these conditions have restricted the measurement of key control parameters, making the control of aluminum reduction cells a difficult problem in the industry. Because aluminum electrolysis control systems have a significant economic influence, substantial research has been conducted on control algorithms, control systems and information systems for aluminum reduction cells. This article first summarizes the development of control systems and then focuses on the progress made since 2000, including alumina concentration control, temperature control and electrolyte molecular ratio control, fault diagnosis, cell condition prediction and control system expansion. Based on these studies, the concept of a smart aluminum electrolysis plant is proposed. The frame construction, key problems and current progress are introduced. Finally, several future directions are discussed.

  2. Chemical Reduction Synthesis of Iron Aluminum Powders

    NASA Astrophysics Data System (ADS)

    Zurita-Méndez, N. N.; la Torre, G. Carbajal-De; Ballesteros-Almanza, L.; Villagómez-Galindo, M.; Sánchez-Castillo, A.; Espinosa-Medina, M. A.

    In this study, a chemical reduction synthesis method of iron aluminum (FeAl) nano-dimensional intermetallic powders is described. The process has two stages: a salt reduction and solvent evaporation by a heat treatment at 1100°C. The precursors of the synthesis are ferric chloride, aluminum foil chips, a mix of Toluene/THF in a 75/25 volume relationship, and concentrated hydrochloric acid as initiator of the reaction. The reaction time was 20 days, the product obtained was dried at 60 °C for 2 h and calcined at 400, 800, and 1100 °C for 4 h each. To characterize and confirm the obtained synthesis products, X-Ray Diffraction (XRD), and Scanning Electron Microscopy (SEM) techniques were used. The results of morphology and chemical characterization of nano-dimensional powders obtained showed a formation of agglomerated particles of a size range of approximately 150 nm to 1.0 μm. Composition of powders was identified as corundum (Al2O3), iron aluminide (FeAl3), and iron-aluminum oxides (Fe0. 53Al0. 47)2O3 phases. The oxide phases formation were associated with the reaction of atmospheric concentration-free oxygen during synthesis and sintering steps, reducing the concentration of the iron aluminum phase.

  3. Aluminum stress signaling in plants

    PubMed Central

    Baluska, Frantisek; Matsumoto, Hideaki

    2009-01-01

    Aluminum (Al) toxicity is a major constraint for crop production in acidic soil worldwide. When the soil pH is lower than 5, Al3+ is released to the soil and enters into root tip cell ceases root development of plant. In acid soil with high mineral content, Al is the major cause of phytotoxicity. The target of Al toxicity is the root tip, in which Al exposure causes inhibition of cell elongation and cell division, leading to root stunting accompanied by reduced water and nutrient uptake. A variety of genes have been identified that are induced or repressed upon Al exposure. At tissue level, the distal part of the transition zone is the most sensitive to Al. At cellular and molecular level, many cell components are implicated in the Al toxicity including DNA in nucleus, numerous cytoplastic compounds, mitochondria, the plasma membrane and the cell wall. Although it is difficult to distinguish the primary targets from the secondary effects so far, understanding of the target sites of the Al toxicity is helpful for elucidating the mechanisms by which Al exerts its deleterious effects on root growth. To develop high tolerance against Al stress is the major goal of plant sciences. This review examines our current understanding of the Al signaling with the physiological, genetic and molecular approaches to improve the crop performance under the Al toxicity. New discoveries will open up new avenues of molecular/physiological inquiry that should greatly advance our understanding of Al tolerance mechanisms. Additionally, these breakthroughs will provide new molecular resources for improving the crop Al tolerance via molecular-assisted breeding and biotechnology. PMID:19820334

  4. Process simulation of aluminum reduction cells

    SciTech Connect

    Tabsh, I.; Dupuis, M.; Gomes, A.

    1996-10-01

    A program was developed to model the dynamic behavior of an aluminum reduction cell. The program simulates the physical process by solving the heat and mass balance equations that characterize the behavior of eleven chemical species in the system. It also models operational events (such as metal tapping, anode change, etc.) and the process control logic including various alumina feeding policies and anode effect quenching. The program is a PC based Windows{reg_sign} application that takes full advantage of the Windows user interface. This paper describes the implementation of the process model and the control logic. Various results using the simulation are compared to measured data.

  5. Aluminum exclusion and aluminum tolerance in woody plants

    PubMed Central

    Brunner, Ivano; Sperisen, Christoph

    2013-01-01

    The aluminum (Al) cation Al3+ is highly rhizotoxic and is a major stress factor to plants on acid soils, which cover large areas of tropical and boreal regions. Many woody plant species are native to acid soils and are well adapted to high Al3+ conditions. In tropical regions, both woody Al accumulator and non-Al accumulator plants occur, whereas in boreal regions woody plants are non-Al accumulators. The mechanisms of these adaptations can be divided into those that facilitate the exclusion of Al3+ from root cells (exclusion mechanisms) and those that enable plants to tolerate Al3+ once it has entered the root and shoot symplast (internal tolerance mechanisms). The biochemical and molecular basis of these mechanisms have been intensively studied in several crop plants and the model plant Arabidopsis. In this review, we examine the current understanding of Al3+ exclusion and tolerance mechanisms from woody plants. In addition, we discuss the ecology of woody non-Al accumulator and Al accumulator plants, and present examples of Al3+ adaptations in woody plant populations. This paper complements previous reviews focusing on crop plants and provides insights into evolutionary processes operating in plant communities that are widespread on acid soils. PMID:23781222

  6. Method And Reactor For Production Of Aluminum By Carbothermic Reduction Of Alumina

    DOEpatents

    Aune, Jan Arthur; Johansen, Kai

    2004-10-19

    A hollow partition wall is employed to feed carbon material to an underflow of a carbothermic reduction furnace used to make aluminum. The partition wall divides a low temperature reaction zone where aluminum oxide is reacted with carbon to form aluminum carbide and a high temperature reaction zone where the aluminum carbide and remaining aluminum oxide are reacted to form aluminum and carbon monoxide.

  7. SCALEUP OF ALUMINUM PHOSPHATE CATALYST FOR PILOT PLANT LPDMEtm RUN

    SciTech Connect

    Andrew W. Wang

    2002-01-01

    The Liquid Phase Dimethyl Ether (LPDME{trademark}) process converts synthesis gas to dimethyl ether in a single slurry bubble column reactor. A mixed slurry of methanol synthesis catalyst and methanol dehydration catalyst in a neutral mineral oil simultaneously synthesizes methanol from syngas and converts some of it to dimethyl ether and water. The reaction scheme is shown below: 2H{sub 2} + CO = CH{sub 3}OH; 2CH{sub 3}OH = CH{sub 3}OCH{sub 3} + H{sub 2}O; H{sub 2}O + CO = CO{sub 2} + H{sub 2}. Most of the water produced in this reaction is converted to hydrogen by reduction with carbon monoxide (water gas shift reaction). This synergy permits higher per pass conversion than methanol synthesis alone. The enhancement in conversion occurs because dehydration of the methanol circumvents the equilibrium constraint of the syngas-to-methanol step. The slurry bubble column reactor provides the necessary heat transfer capacity to handle the greater heat duty associated with high conversion. In order to improve the stability of the catalyst system, non-stoichiometric aluminum phosphate was proposed as the dehydration catalyst for the LPDME{trademark} process. This aluminum phosphate material is a proprietary catalyst. This catalyst system of a standard methanol catalyst and the aluminum phosphate provided stable process performance that met the program targets under our standard test process conditions in the laboratory. These targets are (1) an initial methanol equivalent productivity of 28 gmol/kg/hr, (2) a CO{sub 2}-free, carbon selectivity of 80% to dimethyl ether and (3) stability of both catalysts equivalent to that of the methanol catalyst in the absence of the aluminum phosphate. A pilot plant trial of the LPDME{trademark} process using the aluminum phosphate catalyst was originally planned for March 1998 at the DOE-owned, Air Products (APCI)-operated facility at LaPorte, Texas. Because the aluminum phosphate catalyst is not commercially available, we initiated a

  8. SCALEUP OF ALUMINUM PHOSPHATE CATALYST FOR PILOT PLANT LPDMEtm RUN

    SciTech Connect

    Andrew W. Wang

    2002-05-15

    The Liquid Phase Dimethyl Ether (LPDME{trademark}) process converts synthesis gas to dimethyl ether in a single slurry bubble column reactor. A mixed slurry of methanol synthesis catalyst and methanol dehydration catalyst in a neutral mineral oil simultaneously synthesizes methanol from syngas and converts some of it to dimethyl ether and water. The reaction scheme is: 2H{sub 2} + CO = CH{sub 3}OH 2CH{sub 3}OH = CH{sub 3}OCH{sub 3} + H{sub 2}O H{sub 2}O + CO = CO{sub 2} + H{sub 2}. Most of the water produced in this reaction is converted to hydrogen by reduction with carbon monoxide (water gas shift reaction). This synergy permits higher per pass conversion than methanol synthesis alone. The enhancement in conversion occurs because dehydration of the methanol circumvents the equilibrium constraint of the syngas-to-methanol step. The slurry bubble column reactor provides the necessary heat transfer capacity to handle the greater heat duty associated with high conversion. In order to improve the stability of the catalyst system, non-stoichiometric aluminum phosphate was proposed as the dehydration catalyst for the LPDME{trademark} process. This aluminum phosphate material is a proprietary catalyst. This catalyst system of a standard methanol catalyst and the aluminum phosphate provided stable process performance that met the program targets under our standard test process conditions in the laboratory. These targets are (1) an initial methanol equivalent productivity of 28 gmol/kg/hr, (2) a CO{sub 2}-free, carbon selectivity of 80% to dimethyl ether and (3) stability of both catalysts equivalent to that of the methanol catalyst in the absence of the aluminum phosphate. A pilot plant trial of the LPDME{trademark} process using the aluminum phosphate catalyst was originally planned for March 1998 at the DOE-owned, Air Products (APCI)-operated facility at LaPorte, Texas. Because the aluminum phosphate catalyst is not commercially available, we initiated a scaleup project

  9. Reduction of Viologen Bisphosphonate Dihalide with Aluminum Foil

    NASA Astrophysics Data System (ADS)

    Abeta Iyere, Peter

    1996-05-01

    An elegant undergraduate experiment similar to the popular "Iodine Clock Reaction" employs the reduction of methyl viologen by hydroxide ion. A major problem with the hydroxide reduction demonstration is that the mechanism is complicated by the existence of competing reaction pathways. It has been suggested that layered metal viologen phosphonates could be used in the design and construction of molecular materials. The active unit in the reversible photocoloration of these layered materials is the viologen bisphosphonate dihalide (VPX). During our study of these phoshponate systems, we discovered the reduction of viologen bisphosphonate dihalide by aluminum foil, mossy zinc, or magnesium turnings in dilute aqueous hydrofluoric acid solution. When we demonstrated this phenomenon with aluminum foil and VPBr in the classroom, the response of our students was enthusiastic. This demonstration can be used as prelaboratory discussion for an undergraduate kinetic experiment based on the same phenomenon.

  10. Nano-aluminum: transport through sand columns and environmental effects on plants and soil communities.

    PubMed

    Doshi, Reeti; Braida, Washington; Christodoulatos, Christos; Wazne, Mahmoud; O'Connor, Gregory

    2008-03-01

    Nano-aluminum is being used in increasing quantities as energetic material. This research addresses the transport of two types of nanosized aluminum particles (with aluminum oxide, or carboxylate ligand coating, Alex and L-Alex, respectively) through sand columns along with associated environmental impacts on soil systems. Surface phenomena and pH are variables controlling the transport of nano-aluminum particles through porous media. pH environment controls solubility and electrostatic interactions between nano-aluminum particles and porous media. (i.e., changes in point of zero charge, agglomeration, etc.). Concentrations (up to 17 mg/L) far greater than the World Health Organization guideline for Al in drinking water (0.2 mg/L) were measured in columns' leachates. Plant uptake studies, mineralization of radiolabeled glucose test and Microtox test were used to investigate the environmental impacts of nano-aluminum on soil communities and plants. It appears that the presence of nano-aluminum particles did not have an adverse effect on the growth of California red kidney bean (Phaseolus vulgaris) and rye grass (Lolium perenne) plants in the concentration range tested. California red beans did not show uptake of aluminum, while the situation was different for rye grass where a 2.5-fold increase in Al concentration in the leaves was observed as compared with control tests. Nano-aluminum particles in suspension do not appear to have an impact on the metabolic activity of Vibrio fischeri. However, when the nano-aluminum particles were amended to the soil, Alex aluminum resulted in a 50% reduction of light output at concentrations below 5000 mg/L soil suspension concentration while L-Alex showed a similar effect at around 17,500 mg/L and the control soil at 37,500 mg/L. Soil respiration studies show that there are not statistical differences between the time and sizes of peaks in CO(2) production and the total mineralization of glucose.

  11. Power plant emissions reduction

    DOEpatents

    Anand, Ashok Kumar; Nagarjuna Reddy, Thirumala Reddy

    2015-10-20

    A system for improved emissions performance of a power plant generally includes an exhaust gas recirculation system having an exhaust gas compressor disposed downstream from the combustor, a condensation collection system at least partially disposed upstream from the exhaust gas compressor, and a mixing chamber in fluid communication with the exhaust gas compressor and the condensation collection system, where the mixing chamber is in fluid communication with the combustor.

  12. Recent Advances in Electrical Resistance Preheating of Aluminum Reduction Cells

    NASA Astrophysics Data System (ADS)

    Ali, Mohamed Mahmoud; Kvande, Halvor

    2017-02-01

    There are two mainpreheating methods that are used nowadays for aluminum reduction cells. One is based on electrical resistance preheating with a thin bed of small coke and/or graphite particles between the anodes and the cathode carbon blocks. The other is flame preheating, where two or more gas or oil burners are used. Electrical resistance preheating is the oldest method, but is still frequently used by different aluminum producers. Many improvements have been made to this method by different companies over the last decade. In this paper, important points pertaining to the preparation and preheating of these cells, as well as measurements made during the preheating process and evaluation of the performance of the preheating, are illustrated. The preheating times of these cells were found to be between 36 h and 96 h for cell currents between 176 kA and 406 kA, while the resistance bed thickness was between 13 mm and 60 mm. The average cathode surface temperature at the end of the preheating was usually between 800°C and 950°C. The effect of the preheating methods on cell life is unclear and no quantifiable conclusions can be drawn. Some works carried out in the mathematical modeling area are also discussed. It is concluded that there is a need for more studies with real situations for preheated cells on the basis of actual measurements. The expected development in electrical resistance preheating of aluminum reduction cells is also summarized.

  13. Recent Advances in Electrical Resistance Preheating of Aluminum Reduction Cells

    NASA Astrophysics Data System (ADS)

    Ali, Mohamed Mahmoud; Kvande, Halvor

    2016-06-01

    ABSTRACT There are two mainpreheating methods that are used nowadays for aluminum reduction cells. One is based on electrical resistance preheating with a thin bed of small coke and/or graphite particles between the anodes and the cathode carbon blocks. The other is flame preheating, where two or more gas or oil burners are used. Electrical resistance preheating is the oldest method, but is still frequently used by different aluminum producers. Many improvements have been made to this method by different companies over the last decade. In this paper, important points pertaining to the preparation and preheating of these cells, as well as measurements made during the preheating process and evaluation of the performance of the preheating, are illustrated. The preheating times of these cells were found to be between 36 h and 96 h for cell currents between 176 kA and 406 kA, while the resistance bed thickness was between 13 mm and 60 mm. The average cathode surface temperature at the end of the preheating was usually between 800°C and 950°C. The effect of the preheating methods on cell life is unclear and no quantifiable conclusions can be drawn. Some works carried out in the mathematical modeling area are also discussed. It is concluded that there is a need for more studies with real situations for preheated cells on the basis of actual measurements. The expected development in electrical resistance preheating of aluminum reduction cells is also summarized.

  14. Reduction of Oxidative Melt Loss of Aluminum and Its Alloys

    SciTech Connect

    Dr. Subodh K. Das; Shridas Ningileri

    2006-03-17

    identified as the primary factor that accelerates dross formation specifically in the transition from two phases to three phase growth. Limiting magnesium oxidation on the surface of molten aluminum therefore becomes the key to minimizing melt loss, and technology was developed to prevent magnesium oxidation on the aluminum surface. This resulted in a lot of the work being focused on the control of Mg oxidation. Two potential molten metal covering agents that could inhibit dross formation during melting and holding consisting of boric acid and boron nitride were identified. The latter was discounted by industry as it resulted in Boron pick up by the melt beyond that allowed by specifications during plant trials. The understanding of the kinetics of dross formation by the industry partners helped them understand how temperature, alloy chemistry and furnace atmosphere (burner controls--e.g. excess air) effected dross formation. This enables them to introduce in their plant process changes that reduced unnecessary holding at high temperatures, control burner configurations, reduce door openings to avoid ingress of air and optimize charge mixes to ensure rapid melting and avoid excess oxidation.

  15. Nitrate reduction in water by aluminum alloys particles.

    PubMed

    Bao, Zunsheng; Hu, Qing; Qi, Weikang; Tang, Yang; Wang, Wei; Wan, Pingyu; Chao, Jingbo; Yang, Xiao Jin

    2017-07-01

    Nano zero-valent iron (NZVI) particles have been extensively investigated for nitrate reduction in water. However, the reduction by NZVI requires acidic pH conditions and the final product is exclusively ammonium, leading to secondary contamination. In addition, nanomaterials have potential threats to environment and the transport and storage of nanomaterials are of safety concerns. Aluminum, the most abundant metal element in the earth's crust, is able to reduce nitrate, but the passivation of aluminum limits its application. Here we report Al alloys (85% Al) with Fe, Cu or Si for aqueous nitrate reduction. The Al alloys particles of 0.85-0.08 mm were inactivate under ambient conditions and a simple treatment with warm water (45 °C) quickly activated the alloy particles for rapid reduction of nitrate. The Al-Fe alloy particles at a dosage of 5 g/L rapidly reduced 50 mg-N/L nitrate at a reaction rate constant (k) of 3.2 ± 0.1 (mg-N/L)(1.5)/min between pH 5-6 and at 4.0 ± 0.1 (mg-N/L)(1.5)/min between pH 9-11. Dopping Cu in the Al-Fe alloy enhanced the rates of reduction whereas dopping Si reduced the reactivity of the Al-Fe alloy. The Al alloys converted nitrate to 20% nitrogen and 80% ammonium. Al in the alloy particles provided electrons for the reduction and the intermetallic compounds in the alloys were likely to catalyze nitrate reduction to nitrogen. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Polyphenol-aluminum complex formation: Implications for aluminum tolerance in plants

    USDA-ARS?s Scientific Manuscript database

    Natural polyphenols may play an important role in aluminum detoxification in some plants. We examined the interaction between Al3+ and the purified high molecular weight polyphenols pentagalloyl glucose (940 Da) and oenothein B (1568 Da), and the related compound methyl gallate (184 Da) at pH 4 and ...

  17. The role of aluminum sensing and signaling in plant aluminum resistance

    USDA-ARS?s Scientific Manuscript database

    As researchers have gained a better understanding in recent years into the physiological, molecular and genetic basis of how plants deal with aluminum (Al) toxicity in acid soils prevalent in the tropics and sub-tropics, it has become clear that an important component of these responses is the trigg...

  18. Defect reduction in seeded aluminum nitride crystal growth

    DOEpatents

    Bondokov, Robert T.; Morgan, Kenneth E.; Schowalter, Leo J.; Stack, Glen A.

    2017-04-18

    Bulk single crystal of aluminum nitride (AlN) having an areal planar defect density.ltoreq.100 cm.sup.-2. Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.

  19. Defect reduction in seeded aluminum nitride crystal growth

    DOEpatents

    Bondokov, Robert T.; Morgan, Kenneth E.; Schowalter, Leo J.; Slack, Glen A.

    2017-06-06

    Bulk single crystal of aluminum nitride (AlN) having an areal planar defect density .ltoreq.100 cm.sup.-2. Methods for growing single crystal aluminum nitride include melting an aluminum foil to uniformly wet a foundation with a layer of aluminum, the foundation forming a portion of an AlN seed holder, for an AlN seed to be used for the AlN growth. The holder may consist essentially of a substantially impervious backing plate.

  20. Polyphenol-Aluminum Complex Formation: Implications for Aluminum Tolerance in Plants.

    PubMed

    Zhang, Liangliang; Liu, Ruiqiang; Gung, Benjamin W; Tindall, Steven; Gonzalez, Javier M; Halvorson, Jonathan J; Hagerman, Ann E

    2016-04-20

    Natural polyphenols may play an important role in aluminum detoxification in some plants. We examined the interaction between Al(3+) and the purified high molecular weight polyphenols pentagalloyl glucose (940 Da) and oenothein B (1568 Da), and the related compound methyl gallate (184 Da) at pH 4 and 6. We used spectrophotometric titration and chemometric modeling to determine stability constants and stoichiometries for the aluminum-phenol (AlL) complexes. The structures and spectral features of aluminum-methyl gallate complexes were evaluated with quantum chemical calculations. The high molecular weight polyphenols formed Al3L2 complexes with conditional stability constants (β) ∼ 1 × 10(23) at pH 6 and AlL complexes with β ∼ 1 × 10(5) at pH 4. Methyl gallate formed AlL complexes with β = 1 × 10(6) at pH 6 but did not complex aluminum at pH 4. At intermediate metal-to-polyphenol ratios, high molecular weight polyphenols formed insoluble Al complexes but methyl gallate complexes were soluble. The high molecular weight polyphenols have high affinities and solubility features that are favorable for a role in aluminum detoxification in the environment.

  1. Further studies on calculation method of magnetic field in aluminum reduction cell

    SciTech Connect

    Li Guohua; Li Dexiang; Li Dianfeng

    1996-10-01

    On the basis of studies on the theory of using the two scalar potentials method for calculating magnetic fields in aluminum reduction cells, the authors further studied various techniques of this method to calculate magnetic fields in aluminum reduction cells. These techniques include the following items: discretization of the region to be solved in the aluminum reduction cell; derivation of formulas of calculating the elemental characteristics; configuration and storage of the total systematic equation; process for the nonlinear problem in aluminum reduction cell; derivation of formulas for calculating the magnetic fields intensities in aluminum reduction cell by using the scalar potentials (total scalar potential and reduced scalar potential). These techniques determine the degree of putting the method into practical use. Also, the verification and application of this method are given in the paper.

  2. Coordination between Apoplastic and Symplastic Detoxification Confers Plant Aluminum Resistance1[C][W][OPEN

    PubMed Central

    Zhu, Xiao Fang; Lei, Gui Jie; Wang, Zhi Wei; Shi, Yuan Zhi; Braam, Janet; Li, Gui Xin; Zheng, Shao Jian

    2013-01-01

    Whether aluminum toxicity is an apoplastic or symplastic phenomenon is still a matter of debate. Here, we found that three auxin overproducing mutants, yucca, the recessive mutant superroot2, and superroot1 had increased aluminum sensitivity, while a transfer DNA insertion mutant, xyloglucan endotransglucosylase/hydrolases15 (xth15), showed enhanced aluminum resistance, accompanied by low endogenous indole-3-acetic acid levels, implying that auxin may be involved in plant responses to aluminum stress. We used yucca and xth15 mutants for further study. The two mutants accumulated similar total aluminum in roots and had significantly reduced cell wall aluminum and increased symplastic aluminum content relative to the wild-type ecotype Columbia, indicating that altered aluminum levels in the symplast or cell wall cannot fully explain the differential aluminum resistance of these two mutants. The expression of Al sensitive1 (ALS1), a gene that functions in aluminum redistribution between the cytoplasm and vacuole and contributes to symplastic aluminum detoxification, was less abundant in yucca and more abundant in xth15 than the wild type, consistent with possible ALS1 function conferring altered aluminum sensitivity in the two mutants. Consistent with the idea that xth15 can tolerate more symplastic aluminum because of possible ALS1 targeting to the vacuole, morin staining of yucca root tip sections showed more aluminum accumulation in the cytosol than in the wild type, and xth15 showed reduced morin staining of cytosolic aluminum, even though yucca and xth15 had similar overall symplastic aluminum content. Exogenous application of an active auxin analog, naphthylacetic acid, to the wild type mimicked the aluminum sensitivity and distribution phenotypes of yucca, verifying that auxin may regulate aluminum distribution in cells. Together, these data demonstrate that auxin negatively regulates aluminum tolerance through altering ALS1 expression and aluminum distribution

  3. Conostegia xalapensis (Melastomataceae): an aluminum accumulator plant.

    PubMed

    González-Santana, Iris Hayde; Márquez-Guzmán, Judith; Cram-Heydrich, Silke; Cruz-Ortega, Rocio

    2012-02-01

    In acidic soils, an excess of Al³⁺ is toxic to most plants. The Melastomataceae family includes Al-accumulator genera that tolerate high Al³⁺ by accumulating it in their tissues. Conostegia xalapensis is a common shrub in Mexico and Central America colonizing mainly disturbed areas. Here, we determined whether C. xalapensis is an Al accumulator, and whether it has internal tolerance mechanisms to Al. Soil samples collected from two pastures in the state of Veracruz, Mexico, had low pH and high Al³⁺ concentrations along with low Ca²⁺ levels. Leaves of C. xalapensis from pastures showed up to 19,000 mg Al kg⁻¹ DW (dry weight). In laboratory experiments, 8-month-old seedlings treated with 0.5 and 1.0 mM AlCl₃ for 24 days showed higher number of lateral roots and biomass. Pyrocatechol violet and hematoxylin staining evidenced that Al localized in epidermis and mesophyll cells in leaves and in epidermis and vascular pith in roots. Scanning electron microscope-energy dispersive X-ray microanalysis of Al-treated leaves corroborated that Al is in abaxial and adaxial epidermis and in mesophyll cells (31.2%) in 1.0 mM Al-treatment. Roots of Al-treated plants had glutathione reductase (EC 1.6.4.2) and superoxide dismutase (EC 1.15.1.1) activity higher, and low levels of O₂*⁻ and H₂O₂. C. xalapensis is an Al-accumulator plant that can grow in acidic soils with higher Al³⁺ concentrations, and can be considered as an indicator species for soils with potential Al toxicity. Copyright © Physiologia Plantarum 2011.

  4. Nitric oxide signaling in aluminum stress in plants.

    PubMed

    He, Huyi; Zhan, Jie; He, Longfei; Gu, Minghua

    2012-07-01

    Nitric oxide (NO) is a ubiquitous signal molecule involved in multiple plant responses to environmental stress. In the recent years, the regulating role of NO on heavy metal toxicity in plants is realized increasingly, but knowledge of NO in alleviating aluminum (Al) toxicity is quite limited. In this article, NO homeostasis between its biosynthesis and elimination in plants is presented. Some genes involved in NO/Al network and their expressions are also introduced. Furthermore, the role of NO in Al toxicity and the functions in Al tolerance are discussed. It is proposed that Al toxicity may disrupt NO homeostasis, leading to endogenous NO concentration being lower than required for root elongation in plants. There are many evidences that pointed out that the exogenous NO treatments improve Al tolerance in plants through activating antioxidative capacity to eliminate reactive oxygen species. Most of the work with respect to NO regulating pathways and functions still has to be done in the future.

  5. Commonwealth Aluminum: Manufacturer Conducts Plant-Wide Energy Assessments at Two Aluminum Sheet Production Operations;

    SciTech Connect

    Not Available

    2006-04-01

    DOE Industrial Technologies Program case study describes the savings possible if Commonwealth Aluminum (now Aleris Rolled Products) makes improvements noted in energy assessments at two aluminum mills.

  6. Commonwealth Aluminum: Manufacturer Conducts Plant-Wide Energy Assessments at Two Aluminum Sheet Production Operations

    SciTech Connect

    2006-04-01

    DOE Industrial Technologies Program case study describes the savings possible if Commonwealth Aluminum (now Aleris Rolled Products) makes improvements noted in energy assessments at two aluminum mills.

  7. Low temperature aluminum reduction cell using hollow cathode

    DOEpatents

    Brown, Craig W.; Frizzle, Patrick B.

    2002-08-20

    A method of producing aluminum in an electrolytic cell containing alumina dissolved in an electrolyte. A plurality of non-consumable anodes are disposed substantially vertically in the electrolyte along with a plurality of monolithic hollow cathodes. Each cathode has a top and bottom and the cathodes are disposed vertically in the electrolyte and the anodes and the cathodes are arranged in alternating relationship. Each of the cathodes is comprised of a first side facing a first opposing anode and a second side facing a second opposing anode. The first and second sides are joined by ends to form a reservoir in the hollow cathode for collecting aluminum therein deposited at the cathode.

  8. Carbothermic reduction and prereduced charge for producing aluminum-silicon alloys

    DOEpatents

    Stevenson, David T.; Troup, Robert L.

    1985-01-01

    Disclosed is a method for the carbothermic reduction of aluminum oxide to form an aluminum alloy including producing silicon carbide by heating a first mix of carbon and silicon oxide in a combustion reactor to an elevated temperature sufficient to produce silicon carbide at an accelerated rate, the heating being provided by an in situ combustion with oxygen gas, and then admixing the silicon carbide with carbon and aluminum oxide to form a second mix and heating the second mix in a second reactor to an elevated metal-forming temperature sufficient to produce aluminum-silicon alloy. The prereduction step includes holding aluminum oxide substantially absent from the combustion reactor. The metal-forming step includes feeding silicon oxide in a preferred ratio with silicon carbide.

  9. Carbothermic reduction and prereduced charge for producing aluminum-silicon alloys

    DOEpatents

    Stevenson, D.T.; Troup, R.L.

    1985-01-01

    Disclosed is a method for the carbothermic reduction of aluminum oxide to form an aluminum alloy including producing silicon carbide by heating a first mix of carbon and silicon oxide in a combustion reactor to an elevated temperature sufficient to produce silicon carbide at an accelerated rate, the heating being provided by an in situ combustion with oxygen gas, and then admixing the silicon carbide with carbon and aluminum oxide to form a second mix and heating the second mix in a second reactor to an elevated metal-forming temperature sufficient to produce aluminum-silicon alloy. The prereduction step includes holding aluminum oxide substantially absent from the combustion reactor. The metal-forming step includes feeding silicon oxide in a preferred ratio with silicon carbide. 1 fig.

  10. Environmental hazards of aluminum to plants, invertebrates, fish, and wildlife.

    PubMed

    Sparling, D W; Lowe, T P

    1996-01-01

    Aluminum is extremely common throughout the world and is innocuous under circumneutral or alkaline conditions. However, in acidic environments, it can be a major limiting factor to many plants and aquatic organisms. The greatest concern for toxicity in North America occurs in areas that are affected by wet and dry acid deposition, such as eastern Canada and the northeastern U.S. Acid mine drainage, logging, and water treatment plant effluents containing alum can be other major sources of Al. In solution, the metal can combine with several different agents to affect toxicity. In general, Al hydroxides and monomeric Al are the most toxic forms. Dissolved organic carbons, F, PO(3)3- and SO(4)2- ameliorate toxicity by reducing bioavailability. Elevated metal levels in water and soil can cause serious problems for some plants. Algae tend to be both acid- and Al tolerant and, although some species may disappear with reduced pH, overall algae productivity and biomass are seldom affected if pH is above 3.0. Aluminum and acid toxicity tend to be additive to some algae when pH is less than 4.5. Because the metal binds with inorganic P, it may reduce P availability and reduce productivity. Forest die-backs in North America involving red spruce, Fraser fir, balsam fir, loblolly pine, slash pine, and sugar maples have been ascribed to Al toxicity, and extensive areas of European forests have died because of the combination of high soil Al and low pH. Extensive research on crops has produced Al-resistant cultivars and considerable knowledge about mechanisms of and defenses against toxicity. Very low Al levels may benefit some plants, although the metal is not recognized as an essential nutrient. Hyperaccumulator species of plants may concentrate Al to levels that are toxic to herbivores. Toxicity in aquatic invertebrates is also acid dependent. Taxa such as Ephemeroptera, Plecoptera, and Cladocera are sensitive and may perish when Al is less than 1 mg.L-1 whereas dipterans

  11. Environmental hazards of aluminum to plants, invertebrates, fish, and wildlife

    USGS Publications Warehouse

    Sparling, D.W.; Lowe, T.P.

    1996-01-01

    Aluminum is extremely common throughout the world and is innocuous under circumneutral or alkaline conditions. However, in acidic environments, it can be a maJor limiting factor to many plants and aquatic organisms. The greatest concern for toxicity in North America occurs in areas that are affected by wet and dry acid deposition, such as eastern Canada and the northeastern U.S. Acid mine drainage, logging, and water treatment plant effluents containing alum can be other maJor sources of Al. In solution, the metal can combine with several different agents to affect toxicity. In general, Al hydroxides and monomeric Al are the most toxic forms. Dissolved organic carbons, F, PO(3)3- and SO(4)2- ameliorate toxicity by reducing bioavailability. Elevated metal levels in water and soil can cause serious problems for some plants. Algae tend to be both acid- and Al tolerant and, although some species may disappear with reduced pH, overall algae productivity and biomass are seldom affected if pH is above 3.0. Aluminum and acid toxicity tend to be additive to some algae when pH is less than 4.5. Because the metal binds with inorganic P, it may reduce P availability and reduce productivity. Forest die-backs in North America involving red spruce, Fraser fir, balsam fir, loblolly pine, slash pine, and sugar maples have been ascribed to Al toxicity, and extensive areas of European forests have died because of the combination of high soil Al and low pH. Extensive research on crops has produced Al-resistant cultivars and considerable knowledge about mechanisms of and defenses against toxicity. Very low Al levels may benefit some plants, although the metal is not recognized as an essential nutrient. Hyperaccumulator species of plants may concentrate Al to levels that are toxic to herbivores. Toxicity in aquatic invertebrates is also acid dependent. Taxa such as Ephemeroptera, Plecoptera, and Cladocera are sensitive and may perish when Al is less than 1 mg.L-1 whereas dipterans

  12. Neurologic syndrome in 25 workers from an aluminum smelting plant

    SciTech Connect

    White, D.M.; Longstreth, W.T. Jr.; Rosenstock, L.; Claypoole, K.H.; Brodkin, C.A.; Townes, B.D. )

    1992-07-01

    This article expands on an earlier series of three patients with a neurologic syndrome, who had all worked in an aluminum smelting plant. Twenty-five symptomatic workers from the same plant were referred for a standardized evaluation, including completion of a health questionnaire, neurologic examination, and neuropsychologic evaluation. An exposure index was calculated for each worker based on level and duration of exposure in the potroom, where exposures were the greatest. This index was correlated with symptoms, signs, and neuropsychologic test scores. Twenty-two (88%) of the patients reported frequent loss of balance, and 21 (84%) reported memory loss. Neurologic examination revealed signs of incoordination in 21 (84%) of the patients. Neuropsychologic test results showed preservation in certain spheres of functioning, such as verbal IQ, with substantial impairment in others, particularly memory functioning. On memory tests, 70% to 75% showed mild or greater impairment. The majority (17 of 19 tested, or 89%) showed depression on the Minnesota Multiphasic Personality Inventory. The exposure index was significantly correlated with signs and symptoms of incoordination. This study and others in humans and animals support the existence of a syndrome characterized by incoordination, poor memory, impairment in abstract reasoning, and depression. Aluminum exposure in the potroom seems the most likely cause.

  13. Dose reduction at nuclear power plants

    SciTech Connect

    Baum, J.W.; Dionne, B.J.

    1983-01-01

    The collective dose equivalent at nuclear power plants increased from 1250 rem in 1969 to nearly 54,000 rem in 1980. This rise is attributable primarily to an increase in nuclear generated power from 1289 MW-y to 29,155 MW-y; and secondly, to increased average plant age. However, considerable variation in exposure occurs from plant to plant depending on plant type, refueling, maintenance, etc. In order to understand the factors influencing these differences, an investigation was initiated to study dose-reduction techniques and effectiveness of as low as reasonably achievable (ALARA) planning at light water plants. Objectives are to: identify high-dose maintenance tasks and related dose-reduction techniques; investigate utilization of high-reliability, low-maintenance equipment; recommend improved radioactive waste handling equipment and procedures; examine incentives for dose reduction; and compile an ALARA handbook.

  14. Reduction of Annealing Times for Energy Conservation in Aluminum

    SciTech Connect

    Anthony D. Rollett; Hasso Weiland; Mohammed Alvi; Abhijit Brahme

    2005-08-31

    Carnegie Mellon University was teamed with the Alcoa Technical Center with support from the US Dept. of Energy (Office of Industrial Technology) and the Pennsylvania Technology Investment Authority (PTIA) to make processing of aluminum less costly and more energy efficient. Researchers in the Department of Materials Science and Engineering have investigated how annealing processes in the early stages of aluminum processing affect the structure and properties of the material. Annealing at high temperatures consumes significant amounts of time and energy. By making detailed measurements of the crystallography and morphology of internal structural changes they have generated new information that will provide a scientific basis for shortening processing times and consuming less energy during annealing.

  15. Cell biology of aluminum toxicity and tolerance in higher plants.

    PubMed

    Matsumoto, H

    2000-01-01

    Aluminum is the major element in the soil and exists as a stable complex with oxygen and silicate in neutral and weakly acidic soil. When the soil pH is lower than 4.5-5.0, Al is solubilized in the soil water and absorbed by plant roots. Absorbed Al inhibits root elongation severely, and the elongation of roots exposed to Al3+ as low as mumol level is inhibited within an hour(s). Thus much research has been conducted to understand the mechanism of Al toxicity and tolerance. Al is located specifically at the root apex. Al-sensitive plants absorb more Al than do Al-tolerant plants, and thus the exclusion mechanism of Al is the major idea for Al tolerance. The understanding of Al stress in plants is important for stable food production in future. Al is a complicated ion in its chemical form and biological function. In this chapter, mechanisms of Al toxicity and tolerance proposed during the past few decades as well as future topics are described from physiological and molecular points of view.

  16. Molecular and physiological strategies to increase aluminum resistance in plants.

    PubMed

    Inostroza-Blancheteau, Claudio; Rengel, Zed; Alberdi, Miren; de la Luz Mora, María; Aquea, Felipe; Arce-Johnson, Patricio; Reyes-Díaz, Marjorie

    2012-03-01

    Aluminum (Al) toxicity is a primary limitation to plant growth on acid soils. Root meristems are the first site for toxic Al accumulation, and therefore inhibition of root elongation is the most evident physiological manifestation of Al toxicity. Plants may resist Al toxicity by avoidance (Al exclusion) and/or tolerance mechanisms (detoxification of Al inside the cells). The Al exclusion involves the exudation of organic acid anions from the root apices, whereas tolerance mechanisms comprise internal Al detoxification by organic acid anions and enhanced scavenging of free oxygen radicals. One of the most important advances in understanding the molecular events associated with the Al exclusion mechanism was the identification of the ALMT1 gene (Al-activated malate transporter) in Triticum aestivum root cells, which codes for a plasma membrane anion channel that allows efflux of organic acid anions, such as malate, citrate or oxalate. On the other hand, the scavenging of free radicals is dependent on the expression of genes involved in antioxidant defenses, such as peroxidases (e.g. in Arabidopsis thaliana and Nicotiana tabacum), catalases (e.g. in Capsicum annuum), and the gene WMnSOD1 from T. aestivum. However, other recent findings show that reactive oxygen species (ROS) induced stress may be due to acidic (low pH) conditions rather than to Al stress. In this review, we summarize recent findings regarding molecular and physiological mechanisms of Al toxicity and resistance in higher plants. Advances have been made in understanding some of the underlying strategies that plants use to cope with Al toxicity. Furthermore, we discuss the physiological and molecular responses to Al toxicity, including genes involved in Al resistance that have been identified and characterized in several plant species. The better understanding of these strategies and mechanisms is essential for improving plant performance in acidic, Al-toxic soils.

  17. Evaluation of aluminum indices to predict aluminum toxicity to plants grown in nutrient solutions

    SciTech Connect

    Alva, A.K.; Blamey, F.P.C.; Edwards, D.G.; Asher, C.J.

    1986-01-01

    Difficulty has been experienced in establishing a suitable aluminum (Al) index to predict Al toxicity to plants grown in nutrient solutions with a wide range of properties. In the present study, relationships were evaluated between root length and (i) concentration of total Al, (ii) concentration of monomeric Al, and (iii) the sum of the activities of monomeric Al species (..sigma..a/sub Al mono/) in solution. Results are reported for soybean (Glycine max (L.) Merr.), subterranean clover (Trifolium subterraneum L.), alfalfa (Medicago sativa L.), and sunflower (Helianthus annuus L.). Total Al concentration in solution, comprising polymeric and monomeric Al species, was a poor index of Al toxicity, confirming the hypothesis that only monomeric Al is toxic to root growth. In solutions with widely differing composition, the concentration of monomeric Al also proved unsatisfactory due to ionic strength effects on the activities of monomeric Al species. ..sigma..a/sub Al mono/ was the best index of Al toxicity, accounting for 72 to 92% of the variation in root length depending on the plant species. Root length was reduced by 50% at ..sigma..a/sub Al mono/ of 7-16 ..mu..M in soybean, 13 ..mu..M in subterranean clover and alfalfa, and 11 ..mu..M in sunflower.

  18. Ring-expansion reaction of oximes with aluminum reductants.

    PubMed

    Cho, Hidetsura; Iwama, Yusuke; Mitsuhashi, Nakako; Sugimoto, Kenji; Okano, Kentaro; Tokuyama, Hidetoshi

    2012-06-14

    The ring-expansion reactions of heterocyclic ketoximes and carbocyclic ketoximes with several reductants such as AlHCl2, AlH3 (alane), LiAlH4, LiAlH(OtBu)3, and (MeOCH2CH2O)2AlH2Na (Red-Al) were examined. Among reductants, AlHCl2 (LiAlH4:AlCl3 = 1:3) in cyclopentyl methyl ether (CPME) has been found to be a suitable reagent for the reaction, and the rearranged cyclic secondary amines were obtained in good to excellent yields.

  19. Alcoa: Plant-Wide Energy Assessment Finds Potential Savings at Aluminum Extrusion Facility. Industrial Technologies Program, Aluminum BestPractices Plant-Wide Assessment Case Study.

    SciTech Connect

    Not Available

    2003-09-01

    Alcoa completed an energy assessment of its Engineered Products aluminum extrusion facility in Plant City, Florida, in 2001. The company identified energy conservation opportunities throughout the plant and prepared a report as an example for performing energy assessments at similar Alcoa facilities. If implemented, the cost of energy for the plant would be reduced by more than$800,000 per year by conserving 3 million kWh of electricity and 150,000 MMBtu of natural gas.

  20. Mechanically working fully-automatic plant for the regeneration of used aluminum cap screws for bottles

    NASA Astrophysics Data System (ADS)

    Schach, V.; Schach, H.

    1983-10-01

    A mechanical separation process for used aluminum cap screws for bottles is described. A prototype separation plant was developed and constructed. Test results indicate low energy consumption, no water pollution, and no emission of noxious vapors.

  1. Final report on DSA methods for monitoring alumina in aluminum reduction cells with cermet anodes

    NASA Astrophysics Data System (ADS)

    Windisch, C. F., Jr.

    1992-04-01

    The Sensors Development Program was conducted at the Pacific Northwest Laboratory (PNL) for the US Department of Energy, Office of Industrial Processes. The work was performed in conjunction with the Inert Electrodes Program at PNL. The objective of the Sensors Development Program in FY 1990 through FY 1992 was to determine whether methods based on digital signal analysis (DSA) could be used to measure alumina concentration in aluminum reduction cells. Specifically, this work was performed to determine whether useful correlations exist between alumina concentration and various DSA-derived quantification parameters, calculated for current and voltage signals from laboratory and field aluminum reduction cells. If appropriate correlations could be found, then the quantification parameters might be used to monitor and, consequently, help control the alumina concentration in commercial reduction cells. The control of alumina concentration is especially important for cermet anodes, which have exhibited instability and excessive wear at alumina concentrations removed from saturation.

  2. Final report on DSA methods for monitoring alumina in aluminum reduction cells with cermet anodes

    SciTech Connect

    Windisch, C.F. Jr.

    1992-04-01

    The Sensors Development Program was conducted at the Pacific Northwest Laboratory (PNL) for the US Department of Energy, Office of Industrial Processes. The work was performed in conjunction with the Inert Electrodes Program at PNL. The objective of the Sensors Development Program in FY 1990 through FY 1992 was to determine whether methods based on digital signal analysis (DSA) could be used to measure alumina concentration in aluminum reduction cells. Specifically, this work was performed to determine whether useful correlations exist between alumina concentration and various DSA-derived quantification parameters, calculated for current and voltage signals from laboratory and field aluminum reduction cells. If appropriate correlations could be found, then the quantification parameters might be used to monitor and, consequently, help control the alumina concentration in commercial reduction cells. The control of alumina concentration is especially important for cermet anodes, which have exhibited instability and excessive wear at alumina concentrations removed from saturation.

  3. Reduction of CO2 to methanol using aluminum ester FLPs

    DOE PAGES

    Smythe, Nathan C.; Dixon, David A.; Garner, III, Edward B.; ...

    2015-10-09

    Herein we report the synthesis of Al-based esters containing halogenated benzene rings. These Lewis acids were paired with phosphines to form frustrated Lewis pairs (FLPs) which could subsequently bind CO2. While these FLPs were not sufficiently water-stable to catalyze the reduction of CO2 to MeOH using NH3BH3 as the reductant, we examine the effect of varying Lewis acid strength. Frustrated Lewis pairs (FLPs) are combinations of Lewis acids and Lewis bases where the acid and base are either sterically or geometrically restricted from interacting as strongly as their electronic structures would allow. This effect leads to enhanced reactivity towards smallmore » molecules and, consequently, interest in their potential as metal-free catalysts [1], [2], [3], [4] and [5]. Furthermore, to-date, the biggest success has been based around the ability of a myriad of systems to heterolytically cleave H2 and perform catalytic hydrogenations [2] and [3].« less

  4. Evolution of the Busbar Structure in Large-Scale Aluminum Reduction Cells

    NASA Astrophysics Data System (ADS)

    Zhang, Hongliang; Liang, Jinding; Li, Jie; Sun, Kena; Xiao, Jin

    2017-02-01

    Studies of magnetic field and magneto-hydro-dynamics are regarded as the foundation for the development of large-scale aluminum reduction cells, while due to the direct relationship between the busbar configuration and magnetic compensation, the actual key content is the configuration of the busbar. As the line current has been increased from 160 kA to 600 kA, the configuration of the busbar was becoming more complex. To summarize and explore the evolution of busbar configuration in aluminum reduction cells, this paper has reviewed various representative large-scale pre-baked aluminum reduction cell busbar structures, such as end-to-end potlines, side-by-side potlines and external compensation current. The advantages and disadvantages in the magnetic distribution or technical specifications have also been introduced separately, especially for the configurations of the mainstream 400-kA potlines. In the end, the development trends of the bus structure configuration were prospected, based on the recent successful applications of super-scale cell busbar structures in China (500-600 kA).

  5. Evolution of the Busbar Structure in Large-Scale Aluminum Reduction Cells

    NASA Astrophysics Data System (ADS)

    Zhang, Hongliang; Liang, Jinding; Li, Jie; Sun, Kena; Xiao, Jin

    2016-10-01

    Studies of magnetic field and magneto-hydro-dynamics are regarded as the foundation for the development of large-scale aluminum reduction cells, while due to the direct relationship between the busbar configuration and magnetic compensation, the actual key content is the configuration of the busbar. As the line current has been increased from 160 kA to 600 kA, the configuration of the busbar was becoming more complex. To summarize and explore the evolution of busbar configuration in aluminum reduction cells, this paper has reviewed various representative large-scale pre-baked aluminum reduction cell busbar structures, such as end-to-end potlines, side-by-side potlines and external compensation current. The advantages and disadvantages in the magnetic distribution or technical specifications have also been introduced separately, especially for the configurations of the mainstream 400-kA potlines. In the end, the development trends of the bus structure configuration were prospected, based on the recent successful applications of super-scale cell busbar structures in China (500-600 kA).

  6. Non-consumable anode and lining for aluminum electrolytic reduction cell

    DOEpatents

    Beck, Theodore R.; Brooks, Richard J.

    1994-01-01

    An oxidation resistant, non-consumable anode, for use in the electrolytic reduction of alumina to aluminum, has a composition comprising copper, nickel and iron. The anode is part of an electrolytic reduction cell comprising a vessel having an interior lined with metal which has the same composition as the anode. The electrolyte is preferably composed of a eutectic of AlF.sub.3 and either (a) NaF or (b) primarily NaF with some of the NaF replaced by an equivalent molar amount of KF or KF and LiF.

  7. The Effect of "Wave Breakers" on the Magnetohydrodynamic Instability in Aluminum Reduction Cells

    NASA Astrophysics Data System (ADS)

    Pedcenko, Alex; Molokov, Sergei; Bardet, Benoit

    2017-02-01

    We report the results of the experiments on the suppression of the MHD instability in a model of the aluminum reduction cells (Pedchenko et al. in EPL 88:24001, 2009). The idea behind the study is to introduce obstacles in the liquid metal to suppress the propagation of the rolling-pad instability wave. As a result, in some configurations with obstacles, we detect lowering of the wave amplitude, reduction of its propagation speed, and rise of the main parameters' thresholds, responsible for the instability onset.

  8. Aluminum industry applications for OTEC

    SciTech Connect

    Jones, M.S.; Leshaw, D.; Sathyanarayana, K.; Sprouse, A.M.; Thiagarajan, V.

    1980-12-01

    The objective of the program is to study the integration issues which must be resolved to realize the market potential of ocean thermal energy conversion (OTEC) power for the aluminum industry. The study established, as a baseline, an OTEC plant with an electrical output of 100 MWe which would power an aluminum reduction plant. The reduction plant would have a nominal annual output of about 60,000 metric tons of aluminum metal. Three modes of operation were studied, viz: 1. A reduction plant on shore and a floating OTEC power plant moored offshore supplying energy by cable. 2. A reduction plant on shore and a floating OTEC power plant at sea supplying energy by means of an ''energy bridge.'' 3. A floating reduction plant on the same platform as the OTEC power plant. For the floating OTEC/aluminum plantship, three reduction processes were examined. 1. The conventional Hall process with prebaked anodes. 2. The drained cathode Hall cell process. 3. The aluminum chloride reduction process.

  9. Electrocatalytic reduction of ortho nitrobenzaldehyde using modified aluminum electrode and its determination.

    PubMed

    Raj, Vairamuthu; Silambarasan, Jayachandran; Rajakumar, Panchanathan

    2014-07-01

    A simple, cost effective and rapid electrochemical method has been developed for the determination of micro level ortho nitrobenzaldehyde (ONB) based on outstanding properties of modified aluminum electrode tin nanorods/anodic aluminum oxide/aluminum (SnNR/AAO/Al) for the first time. The SnNR/AAO/Al electrode was fabricated by a second step anodization, followed by electrodeposition and its electrochemical behavior was investigated in detail. The cyclic voltammetry results indicated that the SnNR/AAO/Al electrode exhibited efficient electrocatalytic activity toward reduction of ONB in the acidic solution. It provides an appreciable improvement of reduction peak for ONB at -0.721V. Furthermore, various kinetic parameters such as transfer electron number, transfer proton number and standard heterogeneous rate constant were calculated from the scan rates. The electrocatalytic behavior was further exploited as a sensitive detection scheme for the ONB determination by differential pulse voltammetry. Under the optimized conditions, the concentration range and detection limit are 0.1-100 μmol/L and 0.05 μmol/L, respectively, for ONB. The analytical performance of this modified sensor has been evaluated for detection of real sample such as river water and recovery of ONB was achieved all-out up to 102.3% under standard addition method. Copyright © 2014. Published by Elsevier B.V.

  10. 36. REDUCTION PLANT CLOSE VIEW OF FURNACE AND BOILER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    36. REDUCTION PLANT - CLOSE VIEW OF FURNACE AND BOILER Reduction Plant furnace and boiler used to provide heat for drying the fish and fish offal, in their conversion to meal. - Hovden Cannery, 886 Cannery Row, Monterey, Monterey County, CA

  11. Cadmium-Aluminum Layered Double Hydroxide Microspheres for Photocatalytic CO2 Reduction.

    PubMed

    Saliba, Daniel; Ezzeddine, Alaa; Sougrat, Rachid; Khashab, Niveen M; Hmadeh, Mohamad; Al-Ghoul, Mazen

    2016-04-21

    We report the synthesis of cadmium-aluminum layered double hydroxide (CdAl LDH) using the reaction-diffusion framework. As the hydroxide anions diffuse into an agar gel matrix containing the mixture of aluminum and cadmium salts at a given ratio, they react to give the LDH. The LDH self-assembles inside the pores of the gel matrix into a unique spherical-porous shaped microstructure. The internal and external morphologies of the particles are studied by electron microscopy and tomography revealing interconnected channels and a high surface area. This material is shown to exhibit a promising performance in the photoreduction of carbon dioxide using solar light. Moreover, the palladium-decorated version shows a significant improvement in its reduction potential at room temperature. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Westinghouse inadvertent plant trip reduction program

    SciTech Connect

    Roberts, G.K.; Candris, A.S.

    1985-01-01

    During recent years, the nuclear power industry has become increasingly aware of the high average number of inadvertent plant trips experienced by commercial units in the United States versus similar experience in other countries, most strikingly, Japan. The need to address this problem stems from the potential consequences which include lost generating capacity (and lost revenue) for the utility, the cost of replacement power, reductions in component and plant life expectancies (due to cycling), and customer dissatisfaction. Perhaps another, more subtle, concern is the impact these trips have on the general public and the confidence that it has in the maturity of the commercial nuclear power program in the United States. This paper serves two purposes: first, it summarizes the program Westinghouse has established to reduce the frequency of unplanned automatic scrams, and second, it discusses several observations, made during the implementation of this program at different utilities.

  13. Effect of Slotted Anode on Gas Bubble Behaviors in Aluminum Reduction Cell

    NASA Astrophysics Data System (ADS)

    Sun, Meijia; Li, Baokuan; Li, Linmin; Wang, Qiang; Peng, Jianping; Wang, Yaowu; Cheung, Sherman C. P.

    2017-08-01

    In the aluminum reduction cells, gas bubbles are generated at the bottom of the anode which eventually reduces the effective current contact area and the system efficiency. To encourage the removal of gas bubbles, slotted anode has been proposed and increasingly adopted by some industrial aluminum reduction cells. Nonetheless, the exact gas bubble removal mechanisms are yet to be fully understood. A three-dimensional (3D) transient, multiphase flow mathematical model coupled with magnetohydrodynamics has been developed to investigate the effect of slotted anode on the gas bubble movement. The Eulerian volume of fluid approach is applied to track the electrolyte (bath)-molten aluminum (metal) interface. Meanwhile, the Lagrangian discrete particle model is employed to handle the dynamics of gas bubbles with considerations of the buoyancy force, drag force, virtual mass force, and pressure gradient force. The gas bubble coalescence process is also taken into account based on the O'Rourke's algorithm. The two-way coupling between discrete bubbles and fluids is achieved by the inter-phase momentum exchange. Numerical predictions are validated against the anode current variation in an industrial test. Comparing the results using slotted anode with the traditional one, the time-averaged gas bubble removal rate increases from 36 to 63 pct; confirming that the slotted anode provides more escaping ways and shortens the trajectories for gas bubbles. Furthermore, the slotted anode also reduces gas bubble's residence time and the probability of coalescence. Moreover, the bubble layer thickness in aluminum cell with slotted anode is reduced about 3.5 mm (17.4 pct), so the resistance can be cut down for the sake of energy saving and the metal surface fluctuation amplitude is significantly reduced for the stable operation due to the slighter perturbation with smaller bubbles.

  14. Alcoa: Plant-Wide Energy Assessment Finds Potential Savings at Aluminum Extrusion Facility

    SciTech Connect

    2003-09-01

    Alcoa completed an energy assessment of its Engineered Products aluminum extrusion facility in Plant City, Florida, in 2001. The company identified energy conservation opportunities throughout the plant and prepared a report as an example for performing energy assessments at similar Alcoa facilities. If implemented, the cost of energy for the plant would be reduced by more than $800,000 per year by conserving 3 million kWh of electricity and 150,000 MMBtu of natural gas.

  15. Wetting behavior and drag reduction of superhydrophobic layered double hydroxides films on aluminum

    NASA Astrophysics Data System (ADS)

    Zhang, Haifeng; Yin, Liang; Liu, Xiaowei; Weng, Rui; Wang, Yang; Wu, Zhiwen

    2016-09-01

    We present a novel method to fabricate Zn-Al LDH (layered double hydroxides) film with 3D flower-like micro-and nanostructure on the aluminum foil. The wettability of the Zn-Al LDH film can be easily changed from superhydrophilic to superhydrophobic with a simple chemical modification. The as-prepared superhydrophobic surfaces have water CAs (contact angles) of 165 ± 2°. In order to estimate the drag reduction property of the surface with different adhesion properties, the experimental setup of the liquid/solid friction drag is proposed. The drag reduction ratio for the as-prepared superhydrophobic sample is 20-30% at low velocity. Bearing this in mind, we construct superhydrophobic surfaces that have numerous technical applications in drag reduction field.

  16. Increasing the Energy Efficiency of Aluminum-Reduction Cells Using Modified Cathodes

    NASA Astrophysics Data System (ADS)

    Jianping, Peng; Yang, Song; Yuezhong, Di; Yaowu, Wang; Naixiang, Feng

    2017-10-01

    A cathode with an inclined surface (5°) and increased bar collector height (230 mm high) was incorporated into two 300-kA industrial aluminum-reduction cells. The voltage of the cells with the modified cathode was reduced by approximately 200 mV when compared with that of a conventional cell with a flat cathode. Through the use of simulations, the reduction in the cell voltage was attributed to the cathode modification (40 mV) and a reduced electrolyte level of 0.5 cm (160 mV). As a result of reduced anode cathode distance (ACD), the ledge toe was extended to the anode shadow by 12 cm. This caused a large inverted horizontal current and a velocity increase. The ledge profile returned to the desired position when the cells were insulated more effectively, and the metal velocity and metal crest in the modified cells were reduced accordingly.

  17. Non Invasive estimation of aluminum concentration in Hall-Heroult reduction cells

    SciTech Connect

    David Bell

    2004-03-01

    The present best practice for the preparation of primary aluminum is by electrolysis of alumina in the traditional Hall-Heroult reduction cell. The process conditions in the electrolyte of this cell required for the reduction to proceed are sufficiently harsh to have precluded the implementation of in situ sensing of the electrolyte composition, specifically the concentration of the ionized alumina. This report reveals the theoretical basis for a non-invasive method for estimation of the ionized alumina concentration which does not require the use of any sensor in direct contact with the cell electrolyte. The proposed method can in principle be applied with equal efficacy to the so-called drained cathode cell designs and to cells having any anode composition, because only knowledge of the electrolyte conduction behavior is required a priori. For an operating cell, the proposed method requires only readily available electrical measurements and the facilities to process the acquired signals. The proposed method rests on the ability to identify certain characteristics of the transients in the reduction cell terminal voltages caused by the quasiperiodic introduction of alumina. It will be shown that these voltage transients manifest measurable properties, in a statistical sense, that should permit estimation of the ionized alumina concentration with a delay of one alumina feed cycle. The next logical step following the present work, consistent with the Aluminum Technology Roadmap [1], is to experimentally verify the predictions made here; no doubt practical refinements to the proposed approach will evolve during the course of experimentation. Successful verification of the proposed estimation method will permit the design of reduction cell control algorithms based directly on the mass balance of alumina in the electrolyte. This report assumes that the reader understands certain basic concepts important to the operation of electrolytic cells, and the Hall-Heroult cell

  18. Proteome modification in tomato plants upon long-term aluminum treatment

    USDA-ARS?s Scientific Manuscript database

    This study aimed to identify the aluminum (Al)-induced proteomes in tomato (Solanum lycopersicum, “Micro-Tom”) after long-term exposure to the stress factor. Plants were treated in Magnavaca’s solution (pH 4.5) supplemented with 7.5 uM Al3+ ion activity over a 4 month period beginning at the emergen...

  19. EXTERIOR VIEW, LOOKING EAST, OF REDUCTION PLANT NO. 6 WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR VIEW, LOOKING EAST, OF REDUCTION PLANT NO. 6 WITH PRIMARY AND SECONDARY LIMESTONE REDUCTION ('CRUSHING') IN PROGRESS AND A FRONT END LOADER (CONFIRM NAME OF VEHICLE?). - Wade Sand & Gravel Company, Reduction Plant No. 6, State Route 78, Thomas, Jefferson County, AL

  20. A case study on algal response to raw and treated effluents from an aluminum plating plant and a pharmaceutical plant.

    PubMed

    Türker Saçan, Melek; Akmehmet Balcioğlu, Işil

    2006-06-01

    The algal growth responses to the effluents of an aluminum plating plant and to the wastewater from an analgesic/antiinflammatory-drug-producing pharmaceutical plant were investigated. Growth response of the marine alga Dunaliella tertiolecta was monitored by measuring the two response parameters optical density (OD(640)) and in vitro chlorophyll fluorescence for a period of 14 days. Generally, the two response measurements gave similar results for all effluents but the raw effluents of the aluminum plating plant due to the composition of the wastewater. All wastes affected algal growth either by inhibition only or by stimulation at low concentrations and inhibition at high concentrations. Since pollutant tolerance of algae biased toxicity test results, acclimation of algae to the raw effluent of the aluminum plating plant was examined. Although the water quality parameters of treated effluent of both plants were in the permitted range reported by the Turkish Water Pollution Control Act, they inhibited growth at higher concentrations, implying that the two treatment plants were inefficient. Therefore, the importance of toxicity tests in wastewater discharge regulations was emphasized.

  1. Identification of the primary lesion of toxic aluminum in plant roots.

    PubMed

    Kopittke, Peter M; Moore, Katie L; Lombi, Enzo; Gianoncelli, Alessandra; Ferguson, Brett J; Blamey, F Pax C; Menzies, Neal W; Nicholson, Timothy M; McKenna, Brigid A; Wang, Peng; Gresshoff, Peter M; Kourousias, George; Webb, Richard I; Green, Kathryn; Tollenaere, Alina

    2015-04-01

    Despite the rhizotoxicity of aluminum (Al) being identified over 100 years ago, there is still no consensus regarding the mechanisms whereby root elongation rate is initially reduced in the approximately 40% of arable soils worldwide that are acidic. We used high-resolution kinematic analyses, molecular biology, rheology, and advanced imaging techniques to examine soybean (Glycine max) roots exposed to Al. Using this multidisciplinary approach, we have conclusively shown that the primary lesion of Al is apoplastic. In particular, it was found that 75 µm Al reduced root growth after only 5 min (or 30 min at 30 µm Al), with Al being toxic by binding to the walls of outer cells, which directly inhibited their loosening in the elongation zone. An alteration in the biosynthesis and distribution of ethylene and auxin was a second, slower effect, causing both a transient decrease in the rate of cell elongation after 1.5 h but also a longer term gradual reduction in the length of the elongation zone. These findings show the importance of focusing on traits related to cell wall composition as well as mechanisms involved in wall loosening to overcome the deleterious effects of soluble Al. © 2015 American Society of Plant Biologists. All Rights Reserved.

  2. Low-temperature aluminum reduction of graphene oxide, electrical properties, surface wettability, and energy storage applications.

    PubMed

    Wan, Dongyun; Yang, Chongyin; Lin, Tianquan; Tang, Yufeng; Zhou, Mi; Zhong, Yajuan; Huang, Fuqiang; Lin, Jianhua

    2012-10-23

    Low-temperature aluminum (Al) reduction is first introduced to reduce graphene oxide (GO) at 100-200 °C in a two-zone furnace. The melted Al metal exhibits an excellent deoxygen ability to produce well-crystallized reduced graphene oxide (RGO) papers with a low O/C ratio of 0.058 (Al-RGO), compared with 0.201 in the thermally reduced one (T-RGO). The Al-RGO papers possess outstanding mechanical flexibility and extremely high electrical conductivities (sheet resistance R(s) ~ 1.75 Ω/sq), compared with 20.12 Ω/sq of T-RGO. More interestingly, very nice hydrophobic nature (90.5°) was observed, significantly superior to the reported chemically or thermally reduced papers. These enhanced properties are attributed to the low oxygen content in the RGO papers. During the aluminum reduction, highly active H atoms from H(2)O reacted with melted Al promise an efficient oxygen removal. This method was also applicable to reduce graphene oxide foams, which were used in the GO/SA (stearic acid) composite as a highly thermally conductive reservoir to hold the phase change material for thermal energy storage. The Al-reduced RGO/SnS(2) composites were further used in an anode material of lithium ion batteries possessing a higher specific capacity. Overall, low-temperature Al reduction is an effective method to prepare highly conductive RGO papers and related composites for flexible energy conversion and storage device applications.

  3. Coal-Fired Power Plant Heat Rate Reductions

    EPA Pesticide Factsheets

    View a report that identifies systems and equipment in coal-fired power plants where efficiency improvements can be realized, and provides estimates of the resulting net plant heat rate reductions and costs for implementation.

  4. Bleb reduction using combined photodisruptive and photocoagulative neodymium-doped yttrium-aluminum-garnet laser.

    PubMed

    Kumar, Harsh; Dangda, Sonal

    2016-12-01

    This case report aims to highlight the role of photodisruptive neodymium-doped yttrium-aluminum-garnet (Nd:YAG) (1064 nm) laser in the treatment of bleb dysesthesia, which occurs in overhanging blebs or with perilimbal spread. Although treatment of such dysesthetic blebs with laser photocoagulation has been previously described, cases where the height of bleb precludes laser penetration, desired effect might not be seen. We herein describe a technique using a combination of photocoagulative (532 nm) and photodisruptive (1064 nm) Nd:YAG laser for a high bleb migrating nasally and inferiorly along the limbus in a 64-year-old female, causing hypotony and consequent macular edema. Successful reduction could be achieved within a week of treatment. By 6 weeks, intraocular pressure improved to 8 mmHg, macular edema subsided, and visual acuity improved to 6/6. Although surgical procedures to correct bleb dysesthesia are available, laser procedures being quick outpatient modalities are more comfortable for the patients.

  5. EXTERIOR VIEW, LOOKING EAST, OF REDUCTION PLANT NO. 6 WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR VIEW, LOOKING EAST, OF REDUCTION PLANT NO. 6 WITH PRIMARY AND SECONDARY LIMESTONE REDUCTION ('CRUSHING') IN PROGRESS. FEEDER (RIGHT) FEEDS TO CONVEYOR BELTS (CENTER) AND CRUSHER (LEFT). LIMESTONE PROCESSED THROUGH THIS OPERATION IS FURTHER SCREENED AND PROCESSED AT ANOTHER PLANT ON THE THOMAS SITE. OPERATION OF THIS PLANT, WHICH BEGAN IN 1960, INCORPORATES WITHIN THE FEEDER A CONCRETE RETAINING WALL DATING TO A TURN OF THE CENTURY QUARRY OPERATION FORMERLY ON THIS SITE. - Wade Sand & Gravel Company, Reduction Plant No. 6, State Route 78, Thomas, Jefferson County, AL

  6. Photoinduced reduction and pattern preservation of giant surface potential on tris(8-hydroxyquinolinato) aluminum(III) thin films

    NASA Astrophysics Data System (ADS)

    Ozasa, Kazunari; Nemoto, Shigeyuki; Isoshima, Takashi; Ito, Eisuke; Maeda, Mizuo; Hara, Masahiko

    2008-12-01

    The characteristics and mechanisms of photoinduced reduction in giant surface potential (gSP) on tris(8-hydroxyquinolinato) aluminum(III) (Alq3) thin films were investigated and discussed from the results of the reduction dependences on exposure time/intensity and the preservation of photopatterned gSP. The reduction dependences are explained well with numerical-model calculation of surface potential reduction due to the drift of photoexcited carriers assuming the Poole-Frenkel formula for electron mobility. The preservation of patterned gSPs suggests the existence of deep traps involved in the carrier-drift mechanism.

  7. Solar Aluminum Production by Vacuum Carbothermal Reduction of Alumina—Thermodynamic and Experimental Analyses

    NASA Astrophysics Data System (ADS)

    Kruesi, M.; Galvez, M. E.; Halmann, M.; Steinfeld, A.

    2011-02-01

    Thermochemical equilibrium calculations indicate the possibility of significantly lowering the onset temperature of aluminum vapor formation via carbothermal reduction of Al2O3 by decreasing the total pressure, enabling its vacuum distillation while bypassing the formation of undesired by-products Al2O, Al4C3, and Al-oxycarbides. Furthermore, the use of concentrated solar energy as the source of high-temperature process heat offers considerable energy savings and reduced concomitant CO2 emissions. When the reducing agent is derived from a biomass source, the solar-driven carbothermal reduction is CO2 neutral. Exploratory experimental runs using a solar reactor were carried out at temperatures in the range 1300 K to 2000 K (1027 °C to 1727 °C) and with total pressures in the range 3.5 to 12 millibar, with reactants Al2O3 and biocharcoal directly exposed to simulated high-flux solar irradiation, yielding up to 19 pct Al by the condensation of product gases, accompanied by the formation of Al4C3 and Al4O4C within the crucible. Based on the measured CO generation, integrated over the duration of the experimental run, the reaction extent reached 55 pct at 2000 K (1727 °C).

  8. A Review of Alumina Feeding and Dissolution Factors in Aluminum Reduction Cells

    NASA Astrophysics Data System (ADS)

    Lavoie, Pascal; Taylor, Mark P.; Metson, James B.

    2016-08-01

    Modern aluminum reduction cells use point feeding technology to replenish alumina as it is consumed by the electrolytic process. The dissolution of alumina has become increasingly difficult to control as the cell sizes and electrolysis intensity have increased. The mass of alumina added per unit time is now much higher than a decade ago, and must take place within a smaller electrolyte mixing volume. In order to replenish the alumina concentration evenly, the alumina needs to be delivered, dispersed, dissolved, and distributed throughout the reduction cell. The dissolution itself follows a 4-step process that can be limited by a multitude of factors. The status of the research on each of these factors is reviewed in the present paper. Although research in laboratory cells has been conducted many times, and the impact of many factors on dissolution has been measured, published observations of alumina feeding on industrial cells are very sparse, especially regarding the dissolution dynamics in the space-time domain and the impact of the feeder hole condition. The present paper therefore presents a qualitative model of the factors governing alumina dissolution in industrial cells and offers the hypothesis that maintenance of the feeder hole condition is central to ensuring alumina dissolution and prevention of sludging.

  9. [Process and mechanism of plants in overcoming acid soil aluminum stress].

    PubMed

    Zhao, Tian-Long; Xie, Guang-Ning; Zhang, Xiao-Xia; Qiu, Lin-Quan; Wang, Na; Zhang, Su-Zhi

    2013-10-01

    Aluminum (Al) stress is one of the most important factors affecting the plant growth on acid soil. Currently, global soil acidification further intensifies the Al stress. Plants can detoxify Al via the chelation of ionic Al and organic acids to store the ionic Al in vacuoles and extrude it from roots. The Al extrusion is mainly performed by the membrane-localized anion channel proteins Al(3+)-activated malate transporter (ALMT) and multi-drug and toxin extrusion (MATE). The genes encoding ABC transporter and zinc-finger protein conferred plant Al tolerance have also been found. The identification of these Al-resistant genes makes it possible to increase the Al resistance of crop plants and enhance their production by the biological methods such as gene transformation and mark-associated breeding. The key problems needed to be solved and the possible directions in the researches of plant Al stress resistance were proposed.

  10. Aluminum toxicity risk reduction as a result of reduced acid deposition in Adirondack lakes and ponds.

    PubMed

    Michelena, Toby M; Farrell, Jeremy L; Winkler, David A; Goodrich, Christine A; Boylen, Charles W; Sutherland, James W; Nierzwicki-Bauer, Sandra A

    2016-11-01

    In 1990, the US Congress amended the Clean Air Act (CAA) to reduce regional-scale ecosystem degradation from SO x and NO x emissions which have been responsible for acid deposition in regions such as the Adirondack Mountains of New York State. An ecosystem assessment project was conducted from 1994 to 2012 by the Darrin Fresh Water Institute to determine the effect of these emission reduction policies on aquatic systems. The project investigated water chemistry and biota in 30 Adirondack lakes and ponded waters. Although regulatory changes made in response to the 1990 CAA amendments resulted in a reduction of acid deposition within the Adirondacks, the ecosystem response to these reductions is complicated. A statistical analysis of SO4, pH, Al, and DOC data collected during this project demonstrates positive change in response to decreased deposition. The changes in water chemistry also have lowered the risk of Al toxicity to brook trout (Salvelinus fontinalis [Mitchill]), which allowed the re-introduction of this species to Brooktrout Lake from which it had been extirpated. However, pH and labile aluminum (Alim) fluctuate and are not strongly correlated to changes in acid deposition. As such, toxicity to S. fontinalis also is cyclic and provides rationale for the difficulties inherent in re-establishing resident populations in impacted aquatic environments. Overall, aquatic ecosystems of the Adirondacks show a positive response to reduced deposition driven by changes in environmental policy, but the response is more complex and indicates an ecosystem-wide interaction between aquatic and watershed components of the ecosystem.

  11. Final report on DSA methods for monitoring alumina in aluminum reduction cells with cermet anodes. Inert Electrodes Program

    SciTech Connect

    Windisch, C.F. Jr.

    1992-04-01

    The Sensors Development Program was conducted at the Pacific Northwest Laboratory (PNL) for the US Department of Energy, Office of Industrial Processes. The work was performed in conjunction with the Inert Electrodes Program at PNL. The objective of the Sensors Development Program in FY 1990 through FY 1992 was to determine whether methods based on digital signal analysis (DSA) could be used to measure alumina concentration in aluminum reduction cells. Specifically, this work was performed to determine whether useful correlations exist between alumina concentration and various DSA-derived quantification parameters, calculated for current and voltage signals from laboratory and field aluminum reduction cells. If appropriate correlations could be found, then the quantification parameters might be used to monitor and, consequently, help control the alumina concentration in commercial reduction cells. The control of alumina concentration is especially important for cermet anodes, which have exhibited instability and excessive wear at alumina concentrations removed from saturation.

  12. In Situ Synthesis Aluminum Borate Whiskers Reinforced TiB2 Matrix Composites for Application in Aluminum Reduction Cells

    NASA Astrophysics Data System (ADS)

    Zhang, Gang; Yang, Jianhong

    2013-11-01

    The TiB2 matrix ceramics reinforced by aluminum borate whiskers (Al18B4O33 w) had been prepared by the pressureless sintering method. The mechanical properties and densification behavior of the TiB2 matrix ceramics were investigated. The results showed that Al18B4O33 w was in situ synthesized by the reaction of boehmite (AlOOH) and TiB2 powders during the sintering process. Increasing the sintering temperature had benefited for densification of the TiB2 matrix ceramics. Al18B4O33 w could increase the flexural strength and Vicker's hardness. It is obtained that the maximum value Vicker's hardness with 1.81 GPa and flexural strength with 82 MPa for samples sintered at 1600°C.

  13. Silicon-Mediated Alleviation of Aluminum Toxicity by Modulation of Al/Si Uptake and Antioxidant Performance in Ryegrass Plants.

    PubMed

    Pontigo, Sofía; Godoy, Karina; Jiménez, Héctor; Gutiérrez-Moraga, Ana; Mora, María de la Luz; Cartes, Paula

    2017-01-01

    Silicon (Si) has been well documented to alleviate aluminum (Al) toxicity in vascular plants. However, the mechanisms underlying these responses remain poorly understood. Here, we assessed the effect of Si on the modulation of Si/Al uptake and the antioxidant performance of ryegrass plants hydroponically cultivated with Al (0 and 0.2 mM) in combination with Si (0, 0.5, and 2.0 mM). Exposure to Al significantly increased Al concentration, mainly in the roots, with a consequent reduction in root growth. However, Si applied to the culture media steadily diminished the Al concentration in ryegrass, which was accompanied by an enhancement in root dry matter production. A reduced concentration of Si in plant tissues was also observed when plants were simultaneously supplied with Al and Si. Interestingly, Si transporter genes (Lsi1 and Lsi2) were down-regulated in roots after Si or Al was applied alone; however, both Lsi1 and Lsi2 were up-regulated as a consequence of Si application to Al-treated plants, denoting that there is an increase in Si requirement in order to cope with Al stress in ryegrass. Whereas Al addition triggered lipid peroxidation, Si contributed to an attenuation of Al-induced oxidative stress by increasing phenols concentration and modulating the activities of superoxide dismutase (SOD), catalase, peroxidase, and ascorbate peroxidase antioxidant enzymes. Differential changes in gene expression of SOD isoforms (Mn-SOD, Cu/Zn-SOD, and Fe-SOD) and the profile of peroxide (H2O2) generation were also induced by Si in Al-stressed plants. This, to the best of our knowledge, is the first study to present biochemical and molecular evidence supporting the effect of Si on the alleviation of Al toxicity in ryegrass plants.

  14. Silicon-Mediated Alleviation of Aluminum Toxicity by Modulation of Al/Si Uptake and Antioxidant Performance in Ryegrass Plants

    PubMed Central

    Pontigo, Sofía; Godoy, Karina; Jiménez, Héctor; Gutiérrez-Moraga, Ana; Mora, María de la Luz; Cartes, Paula

    2017-01-01

    Silicon (Si) has been well documented to alleviate aluminum (Al) toxicity in vascular plants. However, the mechanisms underlying these responses remain poorly understood. Here, we assessed the effect of Si on the modulation of Si/Al uptake and the antioxidant performance of ryegrass plants hydroponically cultivated with Al (0 and 0.2 mM) in combination with Si (0, 0.5, and 2.0 mM). Exposure to Al significantly increased Al concentration, mainly in the roots, with a consequent reduction in root growth. However, Si applied to the culture media steadily diminished the Al concentration in ryegrass, which was accompanied by an enhancement in root dry matter production. A reduced concentration of Si in plant tissues was also observed when plants were simultaneously supplied with Al and Si. Interestingly, Si transporter genes (Lsi1 and Lsi2) were down-regulated in roots after Si or Al was applied alone; however, both Lsi1 and Lsi2 were up-regulated as a consequence of Si application to Al-treated plants, denoting that there is an increase in Si requirement in order to cope with Al stress in ryegrass. Whereas Al addition triggered lipid peroxidation, Si contributed to an attenuation of Al-induced oxidative stress by increasing phenols concentration and modulating the activities of superoxide dismutase (SOD), catalase, peroxidase, and ascorbate peroxidase antioxidant enzymes. Differential changes in gene expression of SOD isoforms (Mn-SOD, Cu/Zn-SOD, and Fe-SOD) and the profile of peroxide (H2O2) generation were also induced by Si in Al-stressed plants. This, to the best of our knowledge, is the first study to present biochemical and molecular evidence supporting the effect of Si on the alleviation of Al toxicity in ryegrass plants. PMID:28487719

  15. Bleb reduction using combined photodisruptive and photocoagulative neodymium-doped yttrium-aluminum-garnet laser

    PubMed Central

    Kumar, Harsh; Dangda, Sonal

    2016-01-01

    This case report aims to highlight the role of photodisruptive neodymium-doped yttrium-aluminum-garnet (Nd:YAG) (1064 nm) laser in the treatment of bleb dysesthesia, which occurs in overhanging blebs or with perilimbal spread. Although treatment of such dysesthetic blebs with laser photocoagulation has been previously described, cases where the height of bleb precludes laser penetration, desired effect might not be seen. We herein describe a technique using a combination of photocoagulative (532 nm) and photodisruptive (1064 nm) Nd:YAG laser for a high bleb migrating nasally and inferiorly along the limbus in a 64-year-old female, causing hypotony and consequent macular edema. Successful reduction could be achieved within a week of treatment. By 6 weeks, intraocular pressure improved to 8 mmHg, macular edema subsided, and visual acuity improved to 6/6. Although surgical procedures to correct bleb dysesthesia are available, laser procedures being quick outpatient modalities are more comfortable for the patients. PMID:28112138

  16. 34. REDUCTION PLANT Furnace and boiler which provided steam heat ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    34. REDUCTION PLANT Furnace and boiler which provided steam heat required in converting fish, and fish offal, into meal and fish oil. Cone shaped tank at right held extracted oil. - Hovden Cannery, 886 Cannery Row, Monterey, Monterey County, CA

  17. TOXICITY REDUCTION EVALUATION PROTOCOL FOR MUNICIPAL WASTEWATER TREATMENT PLANTS

    EPA Science Inventory

    This document presents a generalized protocol for conducting a Toxicity Reduction evaluation (TRE) at a municipal wastewater treatment plant (WWTP). This protocol is designed to provide guidance to municipalities in preparing TRE plans, evaluating the information generated durin...

  18. Sodium-Potassium Alloy for the Reduction of Monoalkyl Aluminum(III) Compounds

    NASA Astrophysics Data System (ADS)

    Schormann, Mark; Klimek, Klaus S.; Hatop, Hagen; Varkey, Saji P.; Roesky, Herbert W.; Lehmann, Christopher; Röpken, Cord; Herbst-Irmer, Regine; Noltemeyer, Mathias

    2001-12-01

    Monoalkylaluminum(III) compounds of the type RAlX2 {R=Cp* (C5Me5), X=Cl, Br, I (1-3); (BisAlCl2)2 (Bis=(Me3Si)2CH) (5); TrisSi [(Me3Si)3Si], X=Cl, Br, I (6-8); CycTris [(CycMe2Si)(Me3Si)2C], X=Me, F, Cl, Br, I (11-15)} were prepared and characterized by NMR-, IR-, and mass spectroscopy as well as elemental analysis. The single-crystal X-ray structures of Cp*AlBr2, TrisSiAlX2·THF (X=Cl, Br, I), CycTrisAlX2·THF (X=Me, Cl, Br, I), and [CycTrisAl(μ-O(CH2)3CH2)]2 are reported. The monoalkylaluminum(I) compound (Cp*Al)4 (4) was isolated after the reduction of Cp*AlX2 (X=Cl, Br, I) using a Na/K alloy. The yield of (Cp*Al)4 has been improved compared to the previously reported method. However, completely different products were obtained when the THF adducts of TrisSiAlI2·THF and CycTrisAlI2·THF were used for the reduction with Na/K alloy. In the former case, the cleavage of the Si-Al bond was observed with the formation of elemental aluminum and (TrisSi)2, while in the latter the THF ring opening reaction occurred. CycTrisAlF2·THF was prepared by reacting CycTrisAlMe2·THF with Me3SnF.

  19. 35. REDUCTION PLANT HOLDING TANKS View just to the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    35. REDUCTION PLANT - HOLDING TANKS View just to the right of Photo No. 34. Note holding tanks for fish awaiting reduction, and cement bases (in front of tanks) for dryers and power units (right). - Hovden Cannery, 886 Cannery Row, Monterey, Monterey County, CA

  20. Valorization of aluminum scrap via an acid-washing treatment for reductive removal of toxic bromate from water.

    PubMed

    Lin, Kun-Yi Andrew; Lin, Jia-Yin; Lien, Hsing-Lung

    2017-04-01

    Aluminum scrap (AS) is adopted for the first time as a readily available aluminum source to prepare zero-valent aluminum (ZVAl) for removing bromate from water via a reductive reaction. Since aluminum is easily oxidized to aluminum oxide (Al2O3) on exposure to air, an acid-washing pretreatment on AS is developed to remove the layer of Al2O3. HCl is found as the most effective acid to pretreat AS and the HCl-pretreated or acid-washed AS (AWAS) is able to remove bromate from water and convert it to bromide. Factors, such as temperature, pH, co-existing anions, and particle size, which influence the bromate removal using AWAS are also investigated. The mechanism of bromate removal by AWAS can be attributed to both reduction and adsorption. The elevated temperature also significantly improves bromate removal capacity of AWAS as well as the reaction kinetics. The bromate removal capacity of AWAS is substantially improved under acidic conditions. However, the basic conditions and co-existing anions suppress or interfere with the interaction between bromate and AWAS, leading to much lower removal capacities. The recyclability of AWAS is also evaluated and the acid-washing regeneration is necessary to restore its capacity. However, the mass of AWAS can gradually decrease due to multi-cycle acid-washing regeneration. Through this study, the valorization of AS via acid-washing is demonstrated and optimization of acid-washing parameters is presented. Our findings reveal that the acid-washing is a useful technique to utilize AS as an inexpensive and efficient material for removing bromate from water.

  1. Leaching of aluminum and iron from boiler slag generated from a typical Chinese Steel Plant.

    PubMed

    Li, Jinping; Gan, Jinhua; Li, Xianwang

    2009-07-30

    This paper presents a new way of recycling aluminum and iron in boiler slag derived from coal combustion plants, which integrates efficient extraction and reuse of the leached pellets together. The boiler slag was pelletized together with washed coal and lime prior to sintering and then was sintered at 800-1200 degrees C for different periods to produce sintered pellets for the leaching test. An elemental analysis of aqueous solutions leached by sulfuric acid was determined by EDTA-Na(2)-ZnCl(2) titration method. The components and microstructures of the samples, sintered pellets and leached residue were examined by means of XRF, XRD and SEM. XRD analysis indicates that predominate minerals such as kaolinite, quartz, calcium silicide, hematate and metakoalin exist in the boiler slag. An aluminum extraction efficiency of 86.50% was achieved. The maximum extraction efficiency of Fe was 94.60% in the same conditions of that for the maximum extraction efficiency of Al. The extraction efficiencies of Al and Fe increased with an increase in temperature, leaching time and acidity. High Al extraction efficiency was obtained for pellets with high CaO content. The final product of alumina would be used directly for the production of metallic aluminum.

  2. Effect of aluminum treatment on proteomes of radicles of seeds derived from Al-treated tomato plants

    USDA-ARS?s Scientific Manuscript database

    Aluminum (Al) toxicity is a major constraint to plant growth and crop yield in acid soils. Tomato cultivars are especially susceptible to excessive A1 3+ accumulated in the root zone. In this study, tomato plants were grown in a hydroponic culture system supplemented with 50 uM AlK(SO4)2. Seeds harv...

  3. [Soil Heavy Metal Spatial Distribution and Source Analysis Around an Aluminum Plant in Baotou].

    PubMed

    Zhang, Lian-ke; Li, Hai-peng; Huang, Xue-min; Li, Yu-mei; Jiao, Kun-ling; Sun, Peng; Wang, Wei-da

    2016-03-15

    The soil with 500 m distance from an aluminum plant in Baotou was studied. A total of 64 soil samples were taken from the 0-5 cm, 5-20 cm, 20-40 cm and 40-60 cm layers, and the contents of Cu, Pb, Zn, Cr, Cd, Ni and Mn were tested, respectively. The correlation analysis and principal component analysis were used to identify the sources of these heavy metals in soils. The results suggested that the contents of Cu, Pb, Zn, Cr, Cd, Ni and Mn in study area were 32.9, 50.35, 69.92, 43.78, 0.54, 554.42 and 36.65 mg · kg⁻¹ respectively. All seven heavy metals tested were overweight compared with the background values of soil in Inner Mongolia. The spatial distribution of heavy metals showed that the horizontal distribution of heavy metals was obviously enriched in the southwest, while in vertical distribution, the heavy metal content (0 to 5 cm) was highest in the surface soil, and the heavy metal content decreased with increasing depth and tended to be stabilized when the depth was over 20 cm. Source analysis showed that the source of Cu, Zn, Cr and Mn might be influenced by the aluminum plant and the surrounding industrial activity. The source of Pb and Cd might be mainly related to road transportation. The source of Ni may be affected by agricultural activities and soil parent material together.

  4. Source reduction from chemical plants using on-line optimization

    SciTech Connect

    Zhang, Z.; Pike, R.W.; Hertwig, T.A.

    1995-12-01

    An effective approach for source reduction in chemical plants has been demonstrated using on-line optimization with flowsheeting (ASPEN PLUS) for process optimization and parameter estimation and the Tjao-Biegler algorithm implemented in a mathematical programming language (GAMS/MINOS) for data reconciliation and gross error detection. Results for a Monsanto sulfuric acid plant with a Bailey distributed control system showed a 25% reduction in the sulfur dioxide emissions and a 17% improvement in the profit over the current operating conditions. Details of the methods used are described.

  5. Final report on the application of chaos theory to an alumina sensor for aluminum reduction cells

    SciTech Connect

    Williford, R.E.; Windisch, C.F. Jr.

    1992-03-01

    Four chaos-related digital signal analysis (DSA) methods were applied to the analysis of voltage and current signals collected from aluminum electrolysis cells. Two separate data bases were analyzed: bench-scale laboratory experiments and a pilot-scale test. The objective was to assess the feasibility of using these types of data and analysis methods as the basis for a non-intrusive sensor to measure the alumina content in the electrolysis bath. This was the first time chaos theory approaches have been employed to analyze aluminum electrolysis cells.

  6. Composite propellant aluminum agglomeration reduction using tailored Al/PTFE particles

    NASA Astrophysics Data System (ADS)

    Sippel, Travis R.

    Micron aluminum is widely used in propellants; however, performance could be significantly improved if ignition barriers could be disrupted and combustion tailored. In solid propellants for example, aluminum increases theoretical specific impulse performance, yet theoretical levels cannot be achieved largely because of two-phase flow losses. These losses could be reduced if particles quickly ignited, more gaseous products were produced, and if particle breakup occurred during combustion. To achieve altered aluminum ignition and particle combustion, this work explores the use of low level (10-30 wt.%) fluorocarbon (polytetrafluoroethylene (PTFE) or poly(carbon monofluoride) (PMF)) inclusion inside of aluminum via low or high energy mechanical activation. Aluminum/PTFE particles are found to be amenable to use in binder based energetics, having average particle sizes ranging from 15 to 78 μm, ~2-7 m2/g, specific surface area, and combustion enthalpies as high as 20.2 kJ/g. Differential scanning calorimetry (DSC) experiments indicate high energy MA reduces both reaction and oxidation onset to ~440 °C that is far below aluminum alone. Safety testing shows these particles have high electrostatic discharge (ESD) (89.9-108 mJ), impact (> 213 cm), and friction (> 360 N) ignition thresholds. The idea of further increasing reactivity and increasing particle combustion enthalpy is explored by reducing fluorocarbon inclusion content to 10 wt.% and through the use of the strained fluorocarbon PMF. Combustion enthalpy and average particle size range from 18.9 to 28.5 kJ/g and 23.0 to 67.5 μm, respectively and depend on MA intensity, duration, and inclusion level. Specific surface areas are high (5.3 to 34.8 m2/g) and as such, Al/PMF particles are appropriate for energetic applications not requiring a curable liquid binder. Mechanical activation reduces oxidation onset (DSC) from 555 to 480 °C (70/30 wt.%). Aluminum/PMF particles are sensitive to ESD (11.5-47.5 mJ) and some

  7. Changes in aluminum concentrations and speciation in lakes across the northeastern U.S. following reductions in acidic deposition.

    PubMed

    Warby, Richard A F; Johnson, Chris E; Driscoll, Charles T

    2008-12-01

    We surveyed 113 lakes in the northeastern U.S. in 2001 that had previously been sampled in 1986 to evaluate the effects of reductions in acidic deposition on the concentrations and speciation of aluminum (Al). We found ubiquitous decreases in the concentrations of total Al and inorganic monomeric aluminum (Ali) across the region. Median total Al decreased from 1.45 to 1.01 micromol L(-1) across the region, with the largest decrease in the Adirondacks (4.60 micromol L(-1) to 2.59 micromol L(-1)). Organic monomeric aluminum (Alo) also decreased region-wide and in all the subregions except the Adirondacks. The speciation of Ali shifted from largely Al-F complexes in 1986 to largely Al-OH complexes in 2001 in ponds whose concentrations were above the detection limit (>0.7 micromol L(-1)). In 2001, only seven lakes studied, representing a population of 130 lakes in the region, had Al1 concentrations above a toxic limit of 2 micromol L(-1) compared with 20 sample lakes, representing 449 lakes, in 1986. Thus, we estimate that more than 300 lakes in the northeastern United States no longer have summer Ali concentrations at levels considered harmful to aquatic biota.

  8. Solution phase synthesis of aluminum-doped silicon nanoparticles via room-temperature, solvent based chemical reduction of silicon tetrachloride

    NASA Astrophysics Data System (ADS)

    Mowbray, Andrew James

    We present a method of wet chemical synthesis of aluminum-doped silicon nanoparticles (Al-doped Si NPs), encompassing the solution-phase co-reduction of silicon tetrachloride (SiCl4) and aluminum chloride (AlCl 3) by sodium naphthalide (Na[NAP]) in 1,2-dimethoxyethane (DME). The development of this method was inspired by the work of Baldwin et al. at the University of California, Davis, and was adapted for our research through some noteworthy procedural modifications. Centrifugation and solvent-based extraction techniques were used throughout various stages of the synthesis procedure to achieve efficient and well-controlled separation of the Si NP product from the reaction media. In addition, the development of a non-aqueous, formamide-based wash solution facilitated simultaneous removal of the NaCl byproduct and Si NP surface passivation via attachment of 1-octanol to the particle surface. As synthesized, the Si NPs were typically 3-15 nm in diameter, and were mainly amorphous, as opposed to crystalline, as concluded from SAED and XRD diffraction pattern analysis. Aluminum doping at various concentrations was accomplished via the inclusion of aluminum chloride (AlCl3); which was in small quantities dissolved into the synthesis solution to be reduced alongside the SiCl4 precursor. The introduction of Al into the chemically-reduced Si NP precipitate was not found to adversely affect the formation of the Si NPs, but was found to influence aspects such as particle stability and dispersibility throughout various stages of the procedure. Analytical techniques including transmission electron microscopy (TEM), FTIR spectroscopy, and ICP-optical emission spectroscopy were used to comprehensively characterize the product NPs. These methods confirm both the presence of Al and surface-bound 1-octanol in the newly formed Si NPs.

  9. An assessment of psychological noise reduction by landscape plants.

    PubMed

    Yang, Fan; Bao, Zhi Yi; Zhu, Zhu Jun

    2011-04-01

    The emphasis in the term 'Green Transportation' is on the word 'green'. Green transportation focuses on the construction of a slow transport system with a visually pleasing, easy and secure trip environment composed of urban parks, green roadside spaces and some other space that is full of landscape plants. This trip environment encourages residents to make trip choices that reduce fuel consumption and pollution and is one of the most important ways of popularizing green transportation. To study the psychological benefits provided by urban parks and other landscape environments, we combined a subjective approach (a questionnaire) with an objective quantitative approach (emotional tests using an electroencephalogram; EEG). Using a questionnaire survey, we found that 90% of the subjects believed that landscape plants contribute to noise reduction and that 55% overrated the plants' actual ability to attenuate noise. Two videos (showing a traffic scene and a plant scene) were shown to 40 participants on video glasses. We detected and recorded EEG values with a portable electroencephalograph, and a comparison between the results of the two groups revealed that there was a highly significant asymmetry between the EEG activity of the vegetation scene and traffic scene groups. The results suggest that the emotions aroused by noise and visual stimuli are manifested in the synchronization of beta frequency band and the desynchronization of alpha frequency band, indicating that landscape plants can moderate or buffer the effects of noise. These findings indicate that landscape plants provide excess noise attenuating effects through subjects' emotional processing, which we term 'psychological noise reduction'.

  10. Closing Plant Stomata Requires a Homolog of an Aluminum-Activated Malate Transporter

    PubMed Central

    Sasaki, Takayuki; Mori, Izumi C.; Furuichi, Takuya; Munemasa, Shintaro; Toyooka, Kiminori; Matsuoka, Ken; Murata, Yoshiyuki; Yamamoto, Yoko

    2010-01-01

    Plant stomata limit both carbon dioxide uptake and water loss; hence, stomatal aperture is carefully set as the environment fluctuates. Aperture area is known to be regulated in part by ion transport, but few of the transporters have been characterized. Here we report that AtALMT12 (At4g17970), a homolog of the aluminum-activated malate transporter (ALMT) of wheat, is expressed in guard cells of Arabidopsis thaliana. Loss-of-function mutations in AtALMT12 impair stomatal closure induced by ABA, calcium and darkness, but do not abolish either the rapidly activated or the slowly activated anion currents previously identified as being important for stomatal closure. Expressed in Xenopus oocytes, AtALMT12 facilitates chloride and nitrate currents, but not those of organic solutes. Therefore, we conclude that AtALMT12 is a novel class of anion transporter involved in stomatal closure. PMID:20154005

  11. Pechiney Rolled Products: Plant-Wide Energy Assessment Identifies Opportunities to Optimize Aluminum Casting and Rolling Operations

    SciTech Connect

    Not Available

    2004-07-01

    A Pechiney Rolled Products plant focused on various aluminum casting processes during a PWA. The assessment revealed potential annual savings of 460,000 MMBtu in natural gas, 9.6 million kWh in electricity, 69 million pounds in CO2, and $2.5 million.

  12. Transcriptional Regulation of Aluminum-Tolerance Genes in Higher Plants: Clarifying the Underlying Molecular Mechanisms.

    PubMed

    Daspute, Abhijit A; Sadhukhan, Ayan; Tokizawa, Mutsutomo; Kobayashi, Yuriko; Panda, Sanjib K; Koyama, Hiroyuki

    2017-01-01

    Aluminum (Al) rhizotoxicity is one of the major environmental stresses that decrease global food production. Clarifying the molecular mechanisms underlying Al tolerance may contribute to the breeding of Al-tolerant crops. Recent studies identified various Al-tolerance genes. The expression of these genes is inducible by Al. Studies of the major Arabidopsis thaliana Al-tolerance gene, ARABIDOPSIS THALIANA ALUMINUM-ACTIVATED MALATE TRANSPORTER 1 (AtALMT1), which encodes an Al-activated malate transporter, revealed that the Al-inducible expression is regulated by a SENSITIVE TO PROTON RHIXOTOXICITY 1 (STOP1) zinc-finger transcription factor. This system, which involves STOP1 and organic acid transporters, is conserved in diverse plant species. The expression of AtALMT1 is also upregulated by several phytohormones and hydrogen peroxide, suggesting there is crosstalk among the signals involved in the transcriptional regulation of AtALMT1. Additionally, phytohormones and reactive oxygen species (ROS) activate various transcriptional responses, including the expression of genes related to increased Al tolerance or the suppression of root growth under Al stress conditions. For example, Al suppressed root growth due to abnormal accumulation of auxin and cytokinin. It activates transcription of TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS 1 and other phytohormone responsive genes in distal transition zone, which causes suppression of root elongation. On the other hand, overexpression of Al inducible genes for ROS-detoxifying enzymes such as GLUTATHIONE-S-TRANSFERASE, PEROXIDASE, SUPEROXIDE DISMUTASE enhances Al resistance in several plant species. We herein summarize the complex transcriptional regulation of an Al-inducible genes affected by STOP1, phytohormones, and ROS.

  13. Biological reduction of graphene oxide using plant leaf extracts.

    PubMed

    Lee, Geummi; Kim, Beom Soo

    2014-01-01

    Two-dimensional graphene has attracted significant attention due to its unique mechanical, electrical, thermal, and optical properties. Most commonly employed methods to chemically reduce graphene oxide to graphene use hydrazine or its derivatives as the reducing agent. However, they are highly hazardous and explosive. Various phytochemicals obtained from different natural sources such as leaves and peels of a plant are used as reducing agents in the preparation of different gold, silver, copper, and platinum nanoparticles. In this study, seven plant leaf extracts (Cherry, Magnolia, Platanus, Persimmon, Pine, Maple, and Ginkgo) were compared for their abilities to reduce graphene oxide. The optimized reaction conditions for the reduction of graphene oxide were determined as follows. Type of plant: Cherry (Prunus serrulata), reaction time: 12 h, composition of the reaction mixture: 16.7% v/v of plant leaf extract in total suspension, and temperature: 95°C. The degree of reduction caused by Cherry leaf extract was analyzed by elemental analysis and X-ray photoelectron spectroscopy. The reduction of graphene oxide was also confirmed by ultraviolet-visible spectroscopy, Fourier transform-infrared spectroscopy, Raman spectroscopy, X-ray diffraction, transmission electron microscopy, and thermogravimetric analysis.

  14. Proteome Modification in Tomato Plants upon Long-Term Aluminum Treatment.

    PubMed

    Zhou, Suping; Okekeogbu, Ikenna; Sangireddy, Sasikiran; Ye, Zhujia; Li, Hui; Bhatti, Sarabjit; Hui, Dafeng; McDonald, Daniel W; Yang, Yong; Giri, Shree; Howe, Kevin J; Fish, Tara; Thannhauser, Theodore W

    2016-05-06

    This study aimed to identify the aluminum (Al)-induced proteomes in tomato (Solanum lycopersicum, "Micro-Tom") after long-term exposure to the stress factor. Plants were treated in Magnavaca's solution (pH 4.5) supplemented with 7.5 μM Al(3+) ion activity over a 4 month period beginning at the emergence of flower buds and ending when the lower mature leaves started to turn yellow. Proteomes were identified using a 8-plex isobaric tags for relative and absolute quantification (iTRAQ) labeling strategy followed by a two-dimensional (high- and low-pH) chromatographic separation and final generation of tandem mass spectrometry (MS/MS) spectra of tryptic peptides on an LTQ-Orbitrap Elite mass spectrometer. Principal component analysis revealed that the Al-treatment had induced systemic alterations in the proteomes from roots and leaves but not seed tissues. The significantly changed root proteins were shown to have putative functions in Al(3+) ion uptake and transportation, root development, and a multitude of other cellular processes. Changes in the leaf proteome indicate that the light reaction centers of photosynthetic machinery are the primary targets of Al-induced stress. Embryo and seed-coat tissues derived from Al-treated plants were enriched with stress proteins. The biological processes involving these Al-induced proteins concur with the physiological and morphological changes, such as the disturbance of mineral homeostasis (higher contents of Al, P, and Fe and reduced contents of S, Zn, and Mn in Al-treated compared to nontreated plants) in roots and smaller sizes of roots and the whole plants. More importantly, the identified significant proteins might represent a molecular mechanism for plants to develop toward establishing the Al tolerance and adaptation mechanism over a long period of stress treatment.

  15. Facile Aluminum Reduction Synthesis of Blue TiO2 with Oxygen Deficiency for Lithium-Ion Batteries.

    PubMed

    Zheng, Jing; Ji, Guangbin; Zhang, Peng; Cao, Xingzhong; Wang, Baoyi; Yu, Linhui; Xu, Zhichuan

    2015-12-07

    An ultrafacile aluminum reduction method is reported herein for the preparation of blue TiO2 nanoparticles (donated as Al-TiO2 , anatase phase) with abundant oxygen deficiency for lithium-ion batteries. Under aluminum reduction, the morphology of the TiO2 nanosheets changes from well-defined rectangular into uniform round or oval nanoparticles and the particle size also decreases from 60 to 31 nm, which can aggressively accelerate the lithium-ion diffusion. Electron paramagnetic resonance (EPR) and positron annihilation lifetime spectroscopy (PALS) results reveal that plentiful oxygen deficiencies relative to the Ti(3+) species were generated in blue Al-TiO2 ; this effectively enhances the electron conductivity of the TiO2 . X-ray photoelectron spectrometry (XPS) analysis indicates that a small peak is observed for the Al-O bond, which probably plays a very important role in the stabilization of the oxygen deficiencies/Ti(3+) species. As a result, the blue Al-TiO2 possesses significantly higher capacity, better rate performance, and a longer cycle life than the white pure TiO2 . Such improvements can be attributed to the decreased particle size, as well as the existence of the oxygen deficiencies/Ti(3+) species.

  16. Sludge reduction by lumbriculus variegatus in Ahvas wastewater treatment plant

    PubMed Central

    2012-01-01

    Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensive health hazards. Application of aquatic worm is an approach to decrease the amount of biological waste sludge produced in wastewater treatment plants. In the present research reduction of the amount of waste sludge from Ahvaz wastewater treatment plant was studied with the aquatic worm Lumbriculus variegatus in a reactor concept. The sludge reduction in the reactor with worm was compared to sludge reduction in a blank reactor (without worm). The effects of changes in dissolved oxygen (DO) concentration up to 3 mg/L (run 1) and up to 6 mg/L (run 2) were studied in the worm and blank reactors. No meaningful relationship was found between DO concentration and the rate of total suspended solids reduction. The average sludge reductions were obtained as 32% (run 1) and 33% (run 2) in worm reactor and 16% (run 1) and 12% (run 2) in the blank reactor. These results showed that the worm reactors may reduce the waste sludge between 2 and 2.75 times higher than in the blank conditions. The obtained results showed that the worm reactor has a high potential for use in large-scale sludge processing. PMID:23369451

  17. Sludge reduction by lumbriculus variegatus in Ahvas wastewater treatment plant.

    PubMed

    Basim, Yalda; Farzadkia, Mahdi; Jaafarzadeh, Nematollah; Hendrickx, Tim

    2012-08-02

    Sludge production is an avoidable problem arising from the treatment of wastewater. The sludge remained after municipal wastewater treatment contains considerable amounts of various contaminants and if is not properly handled and disposed, it may produce extensive health hazards. Application of aquatic worm is an approach to decrease the amount of biological waste sludge produced in wastewater treatment plants. In the present research reduction of the amount of waste sludge from Ahvaz wastewater treatment plant was studied with the aquatic worm Lumbriculus variegatus in a reactor concept. The sludge reduction in the reactor with worm was compared to sludge reduction in a blank reactor (without worm). The effects of changes in dissolved oxygen (DO) concentration up to 3 mg/L (run 1) and up to 6 mg/L (run 2) were studied in the worm and blank reactors. No meaningful relationship was found between DO concentration and the rate of total suspended solids reduction. The average sludge reductions were obtained as 32% (run 1) and 33% (run 2) in worm reactor and 16% (run 1) and 12% (run 2) in the blank reactor. These results showed that the worm reactors may reduce the waste sludge between 2 and 2.75 times higher than in the blank conditions. The obtained results showed that the worm reactor has a high potential for use in large-scale sludge processing.

  18. Mercury Emission From Plants Depends on Reduction by Ascorbate

    NASA Astrophysics Data System (ADS)

    Halbach, S.; Ernst, D.; Fleischmann, F.; Battke, F.

    2007-12-01

    The importance of vegetation for the ecological Hg cycle has been recognized recently. One step in this cycle is the poorly understood phytogenic reduction of dissolved Hg(II) to volatile Hg(0) which had initially been reported for common reed growing on Hg-contaminated sediments. The hitherto unknown mechanism of this reduction was the objective of our investigations. Young barley and European-beech plants were cultivated for 24 h and 2 days, respectively, on a sterile hydroponic medium containing 20-40 µM HgCl2. Within 10 min after seclusion in a closed exposure system, the Hg(0) emission from the encapsulated aerial part of the plants reached 10 times the control value in a plant-free system and was proportional to the Hg(II) concentration in the medium. At 20 µM Hg(II) in the medium, a flux of 12.8 µg Hg(0)/m2/h was estimated for beech leaves. The phytogenic Hg(II) reduction was further examined by addition of powderized homogenates from deep-frozen leaves (barley, beech, Arabidopsis thaliana) or from needles (Norway spruce) to solutions of 1-5 µM Hg(II). These samples consistently produced a strong transient Hg(0) release at neutral pH that was even reinforced in alkaline medium and vanished at acidic pH. The very same pH dependence was observed after addition of pure L(+)-ascorbate (AA) instead of plant material to the HgCl2 solutions, whereas the reductants NADPH and GSH produced only little or no Hg(0), respectively. At neutral and alkaline pH, the Hg(II)-reducing capacity of spruce needle homogenates was 2 - 4 times that of beech leaves, which paralleled a 6-fold difference in AA concentrations. Homogenates from whole wildtype-plants of Arabidopsis reduced 8-times more Hg(II) than those from the AA-deficient mutant vtc1-1 (AA concentration 30% of wild type). A comparison of literature data on AA concentrations revealed for wetland plants a range from 0.3 µmol/g DW (Phragmites communis) over 15.0 (Typha latifolia) to < 34.1 (Spartina altiflora), and

  19. 39. REDUCTION PLANT THIRD FLOOR The dried fish meal ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    39. REDUCTION PLANT - THIRD FLOOR The dried fish meal was blown into the left side of the room (behind the cloth barrier). When the meal settled to the floor level, it was picked up by an Archimedes screw-shaft which carried it to the far end of the room, where it was blown through pipes (supported by a truss) across Cannery Row to the sacking and storage building. - Hovden Cannery, 886 Cannery Row, Monterey, Monterey County, CA

  20. 37. REDUCTION PLANT DRYER Stainless steel screen cylinder, encased ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    37. REDUCTION PLANT - DRYER Stainless steel screen cylinder, encased within an outer steel shell (top half missing). As fish were tumbled by the rotating screen, they were cooked and dried by live steam piped into the dryer through overhead pipes. The dryer is mounted on a slight angle, aiding the process by moving the drying fish towards the exhaust end of the dryer. - Hovden Cannery, 886 Cannery Row, Monterey, Monterey County, CA

  1. Eliminating aluminum toxicity in an acid sulfate soil for rice cultivation using plant growth promoting bacteria.

    PubMed

    Panhwar, Qurban Ali; Naher, Umme Aminun; Radziah, Othman; Shamshuddin, Jusop; Razi, Ismail Mohd

    2015-02-20

    Aluminum toxicity is widely considered as the most important limiting factor for plants growing in acid sulfate soils. A study was conducted in laboratory and in field to ameliorate Al toxicity using plant growth promoting bacteria (PGPB), ground magnesium limestone (GML) and ground basalt. Five-day-old rice seedlings were inoculated by Bacillus sp., Stenotrophomonas maltophila, Burkholderia thailandensis and Burkholderia seminalis and grown for 21 days in Hoagland solution (pH 4.0) at various Al concentrations (0, 50 and 100 μM). Toxicity symptoms in root and leaf were studied using scanning electron microscope. In the field, biofertilizer (PGPB), GML and basalt were applied (4 t·ha-1 each). Results showed that Al severely affected the growth of rice. At high concentrations, the root surface was ruptured, leading to cell collapse; however, no damages were observed in the PGPB inoculated seedlings. After 21 days of inoculation, solution pH increased to >6.0, while the control treatment remained same. Field study showed that the highest rice growth and yield were obtained in the bio-fertilizer and GML treatments. This study showed that Al toxicity was reduced by PGPB via production of organic acids that were able to chelate the Al and the production of polysaccharides that increased solution pH. The release of phytohormones further enhanced rice growth that resulted in yield increase.

  2. Effects of aluminum on DNA synthesis, cellular polyamines, polyamine biosynthetic enzymes and inorganic ions in cell suspension cultures of a woody plant, Catharanthus roseus

    Treesearch

    Rakesh Minocha; Subhash C. Minocha; Stephanie L. Long; Walter C. Shortle

    1992-01-01

    Increased aluminum (Al) solubility in soil waters due to acid precipitation has aroused considerable interest in the problem of Al toxicity in plants. In the present study, an in vitro suspension culture system of Catharanthus roseus (L.) G. Don was used to analyze the effects of aluminum on several biochemical processes in these cells. The aliphatic...

  3. Reduction of radiation exposure in Japanese BWR Nuclear Power Plants

    SciTech Connect

    Morikawa, Yoshitake

    1995-03-01

    The reduction of occupational exposure to radiation during the annual inspection and maintenance outages of Japanese boiling water reactors (BWR) is one of the most important objectives for stable and reliable operation. It was shown that this radiation exposure is caused by radionuclides, such as Co-60, Co-58 and Mn-54 which are produced from the metal elements Co, Ni, and Fe present in the corrosion products of structural materials that had been irradiated by neutrons. Therefore, to reduce radiation sources and exposures in Japanese BWRs, attempts have been reinforced to remove corrosion products and activated corrosion products from the primary coolant system. This paper describes the progress of the application of these measures to Japanese BWRs. Most Japanese BWR-4 and BWR-5 type nuclear power plants started their commercial operations during the 1970s. With the elapse of time during operations, a problem came to the forefront, namely that occupational radiation exposure during plant outages gradually increased, which obstructed the smooth running of inspections and maintenance work. To overcome this problem, extensive studies to derive effective countermeasures for radiation exposure reduction were undertaken, based on the evaluation of the plants operation data.

  4. A simple model for predicting aluminum bound phosphorus formation and internal loading reduction in lakes after aluminum addition to lake sediment.

    PubMed

    Huser, Brian J; Pilgrim, Keith M

    2014-04-15

    The conversion of mobile phosphorus (P) to aluminum bound P (Al-P) after addition of Al to over 300 sub-samples from 35 sediment cores collected from 20 lakes in the upper Midwest, United States was investigated in this study. Consistent relationships between mobile P reduction and Al-P formation were detected across a broad range of mobile sediment P contents (0.04-2.8 g P m(-2) cm(-1) or 0.083-2.8 mg P g(-1)DW) and lake types. The conversion of mobile P to Al-P was dependent on the initial mobile sediment P content and the amount of Al added to the sediment. An empirical model was then developed to predict the formation of Al-P based on the amount of Al added relative to the initial mass of mobile P in the sediment. The results were compared to sediment collected from an Al treated lake and good agreement was found between the model and in-situ changes to sediment P fractions caused by Al treatment. The model developed in this study, unlike previous models with extreme, singular endpoints, allows for a continuum of estimates for mobile P conversion to Al-P, along with efficiency of P binding by Al, as Al dose varies. Model results can be used in conjunction with mobile sediment P based predictions for internal P loading to calculate an Al dose required to meet internal phosphorus loading goals for lake management and restoration without the need for expensive, time consuming Al additions to sediment.

  5. Plant Extracts of Straw from Sugarcane (Saccharum spp.) in the Attenuation of Toxicity by Aluminum

    NASA Astrophysics Data System (ADS)

    Malvestiti, Jacqueline Ap.; Soares, Marcio Roberto; Casagrande, José Carlos

    2014-05-01

    Organic acids from decomposition of sugar cane straw are capable of interacting with elements of the soil solution, attenuating the toxicity by aluminum (Al) and promoting greater movement of cations in the soil profile. This research had as objective to analyze organic acids present in the straw of the sugarcane varieties RB855453, RB966928. The experiment was conducted under laboratory conditions. The experimental design used was the completely randomized, with five repetitions. The results showed that the analysis, chemical characterization and determination of water-soluble organic compounds of plant extracts (malic and acetic acid) was of great importance for the understanding of the development of the root system of sugarcane considering the soil management systems, since they provide information about the ability of the attenuation of the Al, exchangeable acidity of the soil and the mobility of basic cations to the soil sub layers. This study pointed out greater power of exchangeable cations transport throughout the soil profile, and Al neutralization phytotoxic by the vegetable extract of straw of RB867515 variety, because, besides highest content of basic cations and greater electric conductivity, the total concentration of organic acids was higher on the vegetable extract from the straw of this variety.

  6. Lorentz Force Flowmeter for Liquid Aluminum: Laboratory Experiments and Plant Tests

    NASA Astrophysics Data System (ADS)

    Kolesnikov, Yurii; Karcher, Christian; Thess, André

    2011-06-01

    This article aims to demonstrate that molten metal flow at a high temperature can be measured effectively in a contactless manner by using external direct current magnetic fields. The device applied in the present work is termed Lorentz force flowmeter (LFF) and is based on exposing the flow to a magnet system and measuring the drag force acting on it. Two series of measurements are reported. In the first series, we perform a model experiment in the laboratory using the eutectic alloy GaInSn, which is liquid at room temperature. The second series of measurements is devoted to two plant tests on flow measurement of a liquid aluminum alloy. In both tests, the force acting on the magnet system is measured that is equal to the Lorentz force acting on the flow. To generalize our results, we also derive the scaling law that relates the force acting on a localized magnet system to the flow rate of a fluid with arbitrary electrical conductivity. This law shows that LFF, if properly designed, has a wide range of potential applications in ferrous and nonferrous metallurgy.

  7. How do crop plants tolerate acid soils? Mechanisms of aluminum tolerance and phosphorous efficiency.

    PubMed

    Kochian, Leon V; Hoekenga, Owen A; Pineros, Miguel A

    2004-01-01

    Acid soils significantly limit crop production worldwide because approximately 50% of the world's potentially arable soils are acidic. Because acid soils are such an important constraint to agriculture, understanding the mechanisms and genes conferring tolerance to acid soil stress has been a focus of intense research interest over the past decade. The primary limitations on acid soils are toxic levels of aluminum (Al) and manganese (Mn), as well as suboptimal levels of phosphorous (P). This review examines our current understanding of the physiological, genetic, and molecular basis for crop Al tolerance, as well as reviews the emerging area of P efficiency, which involves the genetically based ability of some crop genotypes to tolerate P deficiency stress on acid soils. These are interesting times for this field because researchers are on the verge of identifying some of the genes that confer Al tolerance in crop plants; these discoveries will open up new avenues of molecular/physiological inquiry that should greatly advance our understanding of these tolerance mechanisms. Additionally, these breakthroughs will provide new molecular resources for improving crop Al tolerance via both molecular-assisted breeding and biotechnology.

  8. Nanogoethite formation from oxidation of Fe(II) sorbed on aluminum oxide: implications for contaminant reduction.

    PubMed

    Larese-Casanova, Philip; Cwiertny, David M; Scherer, Michelle M

    2010-05-15

    Ferrous iron [Fe(II)] bound to mineral surfaces has been shown to reduce several important groundwater contaminants, but little is known of the nature of the newly formed, insoluble ferric iron [Fe(III)] and whether it influences the heterogeneous contaminant reduction process. To explore how the formation and evolution of the Fe oxidation products influences contaminant reduction, we measured the kinetics of nitrobenzene reduction by Fe(II) sorbed on alpha-Al(2)O(3) while simultaneously characterizing the Fe oxidation product with Mossbauer spectroscopy and electron microscopy. After a brief period of slow kinetics, the onset of nitrobenzene reduction coincided with a change in particle suspension color from white to yellow-ocher due to formation of nanogoethite rods (alpha-FeOOH) from oxidation of sorbed Fe(II). Formation of nanogoethite on the alpha-Al(2)O(3) particles appears to promote the rapid reduction of nitrobenzene. Our results show that nanogoethite crystals can form rapidly by heterogeneous Fe(II) oxidation, and formation of goethite can profoundly influence contaminant reduction rates by Fe(II).

  9. Short-term aluminum administration in the rat: reductions in bone formation without osteomalacia

    SciTech Connect

    Goodman, W.G.

    1984-05-01

    Aluminum may be a pathogenic factor in dialysis-associated osteomalacia. To study the early effects of Al on bone, cortical bone growth was measured in pair-fed rats given Al and control rats over two consecutive intervals of 28 (period I) and 16 (period II) days, respectively, using tetracycline labeling of bone. Al (2 mg elemental Al per rat) was administered intraperitoneally for 5 days each week, except for the first week of study, when an incremental dose of Al was given. Control rats received saline vehicle only. For the entire 44-day study, bone and matrix formation were reduced from control values in rats given Al. Although bone and matrix formation remained at control levels during period I in rats given Al, both measurements decreased from control values during period II. During Al exposure, bone and matrix apposition at the periosteum were reduced from control levels in period II, but not in period I. Neither osteoid width nor mineralization front width increased from control values in rats given Al. These findings indicate that Al reduces bone and matrix formation early in the course of Al exposure and prior to the development of histologic osteomalacia. Rather than acting as an inhibitor of mineralization, the early effect of Al on bone is the suppression of matrix synthesis. Our results suggest that the state of low bone formation seen in dialysis-associated osteomalacia may be the consequence of a direct toxic effect of Al on the cellular activity of osteoblasts. 29 references, 3 tables.

  10. The Pivotal Role of Alumina Pore Structure in HF Capture and Fluoride Return in Aluminum Reduction

    NASA Astrophysics Data System (ADS)

    McIntosh, Grant J.; Agbenyegah, Gordon E. K.; Hyland, Margaret M.; Metson, James B.

    2016-09-01

    Fluoride emissions during primary aluminum production are mitigated by dry scrubbing on alumina which, as the metal feedstock, also returns fluoride to the pots. This ensures stable pot operation and maintains process efficiency but requires careful optimization of alumina for both fluoride capture and solubility. The Brunauer-Emmett-Teller (BET) surface area of 70-80 m2 g-1 is currently accepted. However, this does not account for pore accessibility. We demonstrate using industry-sourced data that pores <3.5 nm are not correlated with fluoride return. Reconstructing alumina pore size distributions (PSDs) following hydrogen fluoride (HF) adsorption shows surface area is not lost by pore diameter shrinkage, but by blocking the internal porosity. However, this alone cannot explain this 3.5 nm threshold. We show this is a consequence of surface diffusion-based inhibition with surface chemistry probably playing an integral role. We advocate new surface area estimates for alumina which account for pore accessibility by explicitly ignoring <3.5 nm pores.

  11. Effect of Anode Change on Heat Transfer and Magneto-hydrodynamic Flow in Aluminum Reduction Cell

    NASA Astrophysics Data System (ADS)

    Wang, Qiang; Li, Baokuan; Fafard, Mario

    2016-02-01

    In order to explore the impact of anode replacement on heat transfer and magneto-hydrodynamic flow in aluminum smelting cells, a transient three-dimensional coupled mathematical model has been developed. With a steady state magnetic field, an electrical potential approach was used to obtain electromagnetic fields. Joule heating and Lorentz force, which were the source terms in the energy and momentum equations, were updated at each iteration. The phase change of molten electrolyte (bath) was modeled by an enthalpy-based technique in which the mushy zone was treated as a porous medium with porosity equal to the liquid fraction. A reasonable agreement between the test data and simulated results was achieved. Under normal conditions, the bath at the middle of the cell is hotter, while becoming colder at the four corners. Due to the heat extracted from the bath, the temperature of the new cold anode increases over time. The temperature of the bath under the new cold anode therefore quickly drops, resulting in a decrease of the electrical conductivity. More Joule effect is created. In addition, the bath under the new cold anode gradually freezes and flows more slowly. The temperature of the new anode located at the middle of the cell rises faster because of the warmer bath. It is easier to eliminate the effect of anode change when it occurs in the middle of the cell.

  12. An Assessment of Psychological Noise Reduction by Landscape Plants

    PubMed Central

    Yang, Fan; Bao, Zhi Yi; Zhu, Zhu Jun

    2011-01-01

    The emphasis in the term ‘Green Transportation’ is on the word ‘green’. Green transportation focuses on the construction of a slow transport system with a visually pleasing, easy and secure trip environment composed of urban parks, green roadside spaces and some other space that is full of landscape plants. This trip environment encourages residents to make trip choices that reduce fuel consumption and pollution and is one of the most important ways of popularizing green transportation. To study the psychological benefits provided by urban parks and other landscape environments, we combined a subjective approach (a questionnaire) with an objective quantitative approach (emotional tests using an electroencephalogram; EEG). Using a questionnaire survey, we found that 90% of the subjects believed that landscape plants contribute to noise reduction and that 55% overrated the plants’ actual ability to attenuate noise. Two videos (showing a traffic scene and a plant scene) were shown to 40 participants on video glasses. We detected and recorded EEG values with a portable electroencephalograph, and a comparison between the results of the two groups revealed that there was a highly significant asymmetry between the EEG activity of the vegetation scene and traffic scene groups. The results suggest that the emotions aroused by noise and visual stimuli are manifested in the synchronization of beta frequency band and the desynchronization of alpha frequency band, indicating that landscape plants can moderate or buffer the effects of noise. These findings indicate that landscape plants provide excess noise attenuating effects through subjects’ emotional processing, which we term ‘psychological noise reduction’. PMID:21695027

  13. Stereoselective Reduction of Prochiral Ketones by Plant and Microbial Biocatalysts

    PubMed Central

    Javidnia, K.; Faghih-Mirzaei, E.; Miri, R.; Attarroshan, M.; Zomorodian, K.

    2016-01-01

    Chiral alcohols are the key chiral building blocks to many enantiomerically pure pharmaceuticals. The biocatalytic approach in asymmetric reduction of corresponding prochiral ketones to the preparation of these optically pure substances is one of the most promising routes. The stereoselective reduction of different kinds of prochiral ketones catalyzed by various plants and microorganisms was studied in this work. Benzyl acetoacetate, methyl 3-oxopentanoate, ethyl 3-oxopentanoate, and ethyl butyryl acetate were chosen as the model substrates for β-ketoesters. Benzoyl acetonitrile, 3-chloro propiophenone, and 1-acetyl naphthalene were chosen as aromatic aliphatic ketones. Finally, 2-methyl benzophenone and 4-chloro benzophenone were selected as diaryl ketones. Plant catalysis was conducted by Daucus carota, Brassica rapa, Brassica oleracea, Pastinaca sativa, and Raphnus sativus. For microbial catalysis, Aspergillus foetidus, Penicillum citrinum, Saccharomyces carlbergensis, Pichia fermentans, and Rhodotrula glutinis were chosen. Chiral alcohols were obtained in high yields and with optical purity. A superiority in the microorganisms' performance in the bioreduction of prochiral ketones was detected. Among microorganisms, Rhodotrula glutinis showed remarkable results with nearly all substrates and is proposed for future studies. PMID:27168684

  14. Adsorption of oils, heavy metals and dyes by recovered carbon powder from spent pot liner of aluminum smelter plant.

    PubMed

    Mazumder, B; Devi, Sasmita Rani

    2008-07-01

    Aluminum smelter plants employ Hall-Heroult electrolysis cells for electrolysis of molten cryolite to recover aluminum metal by electrolysis. These cells use carbon cathode blocks as a lining material inside. At the end of service life of the cells, pot lines are discarded and new carbon blocks are laid for fresh charging. These used carbon cathode blocks, known as spent pot liners, are heavily infested with toxic elements such as fluoride, cyanide, alkali, etc. Therefore, their disposal in open field poses great environmental risk. A simple process has been developed for decontamination of these spent pot liners and to recover its carbon value. The experiments indicated that this carbon, in the form of fine powder (around 20 micron in size) can absorb toxic elements like heavy metals, dyes, oils, etc. to a great extent and thus can be used for mitigating environmental pollution occuring due to various toxic wastes.

  15. Continuous measurement of peak hydrogen fluoride exposures in aluminum smelter potrooms: instrument development and in-plant evaluation.

    PubMed

    Dando, Neal; Xu, Weizong; Peace, Jon Nathaniel

    2008-02-01

    The aluminum smelting process continuously evolves both sulfur dioxide (SO2) and hydrogen fluoride (HF) gases. The vast majority of these evolved gases are captured by local exhaust ventilation systems and transported to fume treatment centers. Any gas escaping the ventilation systems could create the potential for workplace exposures. Currently, there are no commercially available sensors that are capable of selectively measuring peak concentrations (< 10 sec) of HF in the presence of SO2. This measurement capability is critical for facilitating a better understanding of the etiology of respiratory health effects. This article presents the development and in-plant testing of a portable, tunable diode-based HF sensor that shows equivalent or improved performance relative to NIOSH Method 7902 and is capable of measuring short-term personal peak HF exposure potentials in operating aluminum smelters.

  16. Assessing iron and aluminum-based coagulants for odour and pathogen reductions in sludge digesters and enhanced digestate dewaterability.

    PubMed

    Akgul, Deniz; Abbott, Timothy; Eskicioglu, Cigdem

    2017-11-15

    Anaerobic digestion (AD) is an effective way of recovering energy and nutrients from organic waste. However, several issues including the production of corrosive, highly odorous and toxic volatile sulfur compounds (VSCs) in digester biogas, and long digestion times to achieve sufficient pathogen reductions can limit its wider adoption. In this study, Kemira™ PIX-311 (ferric chloride), PAX XL-6 (aluminum chloride hydroxide sulfate), and PAX XL-19 (polyaluminum chlorohydrate) were added to the digester feeds to evaluate the effects on digester stability, organic removal, VSCs formation in digester headspace, pathogen removal and sludge dewaterability. After preliminary dose trials, two different doses of PIX-311, PAX XL-19, and a 1:1 mixture of PIX-311 and PAX XL-19 were selected. PAX XL-6 was removed from further study as dosing significantly increased VSC levels and the PAX XL-6 dosed digester exhibited signs of instability. During the total operation period of 100days, addition of PIX-311, PAX XL-19, a combination of PIX-311, PAX XL-19 at concentrations of 4000 and 4500mg/kg total solids (TS) to digester feed did not lead to process instability. Biogas yields of all metal added digesters were similar to that of the control (no metal addition) digester. PIX-311 achieved up to a 93% reduction in biogas VSCs, 82% better fecal coliform inactivation and exhibited improved dewaterability over the control digester. The PAX XL-19 dosed digester showed modest reductions in biogas VSC concentrations, pathogen levels and improved dewaterability versus the control. Metal addition can be an effective way to control odours from VSCs, pathogens and to improve dewaterability during AD. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Aluminum reference electrode

    DOEpatents

    Sadoway, D.R.

    1988-08-16

    A stable reference electrode is described for use in monitoring and controlling the process of electrolytic reduction of a metal. In the case of Hall cell reduction of aluminum, the reference electrode comprises a pool of molten aluminum and a solution of molten cryolite, Na[sub 3]AlF[sub 6], wherein the electrical connection to the molten aluminum does not contact the highly corrosive molten salt solution. This is accomplished by altering the density of either the aluminum (decreasing the density) or the electrolyte (increasing the density) so that the aluminum floats on top of the molten salt solution. 1 fig.

  18. Aluminum reference electrode

    DOEpatents

    Sadoway, Donald R.

    1988-01-01

    A stable reference electrode for use in monitoring and controlling the process of electrolytic reduction of a metal. In the case of Hall cell reduction of aluminum, the reference electrode comprises a pool of molten aluminum and a solution of molten cryolite, Na.sub.3 AlF.sub.6, wherein the electrical connection to the molten aluminum does not contact the highly corrosive molten salt solution. This is accomplished by altering the density of either the aluminum (decreasing the density) or the electrolyte (increasing the density) so that the aluminum floats on top of the molten salt solution.

  19. Multibadging reductions at the H. B. Robinson Nuclear Plant

    SciTech Connect

    Farrell, W.E.; Christmas, K.D.; Shelley, M.H. )

    1987-09-01

    Because of the uncertainties involved in high dose work at nuclear power stations, multibadging practices are often quite conservative---the main criterion is when in doubt, multibadge. An analysis of multibadging results from the 1986 refueling outage at the H.B. Robinson Nuclear Plant indicated that multibadging could be reduced if consistent criteria were used. This article reviews the guidance available on multi-badging for non-uniform radiation fields and presents a set of refined multibadging criteria, which incorporate minimum dose rate and integrated dose equivalent thresholds. When used to analyze the multibadging results from the 1986 outage, the criteria indicate that reductions in multibadging of 50% may be possible, without compromising the accuracy of whole-body dose equivalent measurements.

  20. Transformation products of submicron-sized aluminum-substituted magnetite: Color and reductant solubility

    NASA Technical Reports Server (NTRS)

    Golden, D. C.; Ming, D. W.; Lauer, H. V., Jr.

    1991-01-01

    Magnetite, when present as fine particles, is soluble in acid ammonium oxalate (pH equals 3). However, the commonly used extractant for free iron oxides (i.e., citrate dithionite-bicarbonate (CDB) is not very effective in dissolving magnetite in soils and geologic materials. Upon oxidation, magnetite transforms to maghemite; at elevated temperatures, maghemite inverts to hematite. This transformation causes a change in color from black to red and may affect the reductant solubility as well. The objectives here were to examine the color and reflectance spectral characteristics of products during the transformation of magnetite to maghemite to hematite and to study the effect of Al-substitution in magnetite on the above process. Reductant solubility of Al-substituted magnetite, maghemite, and hematite was also studied. In summary, the transformation of magnetite to maghemite was accompanied by a change in color from black to red because of the oxidation of Fe2(+) to Fe3(+). The phase change maghemite to hematite had a relatively minor effect on the color and the reflectance spectra.

  1. Transformation products of submicron-sized aluminum-substituted magnetite: Color and reductant solubility

    NASA Technical Reports Server (NTRS)

    Golden, D. C.; Ming, D. W.; Lauer, H. V., Jr.

    1991-01-01

    Magnetite, when present as fine particles, is soluble in acid ammonium oxalate (pH equals 3). However, the commonly used extractant for free iron oxides (i.e., citrate dithionite-bicarbonate (CDB) is not very effective in dissolving magnetite in soils and geologic materials. Upon oxidation, magnetite transforms to maghemite; at elevated temperatures, maghemite inverts to hematite. This transformation causes a change in color from black to red and may affect the reductant solubility as well. The objectives here were to examine the color and reflectance spectral characteristics of products during the transformation of magnetite to maghemite to hematite and to study the effect of Al-substitution in magnetite on the above process. Reductant solubility of Al-substituted magnetite, maghemite, and hematite was also studied. In summary, the transformation of magnetite to maghemite was accompanied by a change in color from black to red because of the oxidation of Fe2(+) to Fe3(+). The phase change maghemite to hematite had a relatively minor effect on the color and the reflectance spectra.

  2. Reduction of CO2 to methanol using aluminum ester FLPs

    SciTech Connect

    Smythe, Nathan C.; Dixon, David A.; Garner, III, Edward B.; Rickard, Meredith M.; Mendez, Mariano; Scott, Brian Lindley; Zelenay, Barbara; Sutton, Andrew D.

    2015-10-09

    Herein we report the synthesis of Al-based esters containing halogenated benzene rings. These Lewis acids were paired with phosphines to form frustrated Lewis pairs (FLPs) which could subsequently bind CO2. While these FLPs were not sufficiently water-stable to catalyze the reduction of CO2 to MeOH using NH3BH3 as the reductant, we examine the effect of varying Lewis acid strength. Frustrated Lewis pairs (FLPs) are combinations of Lewis acids and Lewis bases where the acid and base are either sterically or geometrically restricted from interacting as strongly as their electronic structures would allow. This effect leads to enhanced reactivity towards small molecules and, consequently, interest in their potential as metal-free catalysts [1], [2], [3], [4] and [5]. Furthermore, to-date, the biggest success has been based around the ability of a myriad of systems to heterolytically cleave H2 and perform catalytic hydrogenations [2] and [3].

  3. Carbothermic Aluminum Production Using Scrap Aluminum As A Coolant

    DOEpatents

    LaCamera, Alfred F.

    2002-11-05

    A process for producing aluminum metal by carbothermic reduction of alumina ore. Alumina ore is heated in the presence of carbon at an elevated temperature to produce an aluminum metal body contaminated with about 10-30% by wt. aluminum carbide. Aluminum metal or aluminum alloy scrap then is added to bring the temperature to about 900-1000.degree. C. and precipitate out aluminum carbide. The precipitated aluminum carbide is filtered, decanted, or fluxed with salt to form a molten body having reduced aluminum carbide content.

  4. Reduction of Sodium Nitrate Liquid Waste in Nuclear Reprocessing Plants

    SciTech Connect

    Numata, M.; Mihara, S.; Kojima, S.; Ito, H.; Kato, T.

    2006-07-01

    Sodium nitrate solution has been generated from nuclear reprocessing plant as a result of neutralization of nitric acid. The sodium nitrate has been immobilized by bitumen, cement or other material in the site and waste packages have been produced. In order to reduce an environmental impact of the waste packages from the reprocessing plant, it is preferable to decompose nitrate ion to harmless gases such as nitrogen. A combination of formic acid and catalyst has been proposed for this purpose. But, the method is inadequate for a full decomposition of the nitrate ion. In addition, a mixture of NO and NO{sub 2} is produced during the reaction. Formaldehyde and hydrazine were selected as reductants and a combined use of Pd-Cu catalyst was tried to decompose the nitrate ion. As a result, the nitrate ion can almost entirely be decomposed without any generation of NO and NO{sub 2}. The test was conducted by 1 L flask. In case of formaldehyde, nitrate ion concentration can be reduced from 0.017 mol/l to 3.9x10{sup -4} mol/l. In case of hydrazine, nitrate concentration can be decreased from 2.8 mol/l to 9.5 x 10{sup -3} mol/l and ammonium ion is detected. The ammonium ion concentration in the final solution is 0.12 mol/l when 2.8 mol/l nitrate is reduced by hydrazine. Chemical reactions for formaldehyde on the Pd-Cu catalyst are estimated as combination of: NO{sub 3-} + HCHO = NO{sub 2-} + HCOOH; 2NO{sub 2-} + 3HCOOH = N{sub 2} + 3CO{sub 2} + 2H{sub 2}O + 2OH-; 4NO{sub 2-} + 3HCHO = 2N{sub 2} + 3CO{sub 2} + H{sub 2}O + 4OH-. the other hand, for hydrazine with the Pd-Cu catalyst: 3N{sub 2}H{sub 4} = 2NH{sub 3} + 2N{sub 2} + 3H{sub 2}; NO{sub 3-} + H{sub 2} = NO{sub 2-} + H{sub 2}O; NO{sub 2-} + NH{sub 3} = N{sub 2} + H{sub 2}O + OH-. The fundamental research shows that the combination usage of the Pd-Cu catalyst and formaldehyde or hydrazine is applicable for the reduction of nitrate liquid waste in the nuclear reprocessing plant. (authors)

  5. Reduction of adult hippocampal neurogenesis is amplified by aluminum exposure in a model of type 2 diabetes

    PubMed Central

    Nam, Sung Min; Kim, Jong Whi; Yoo, Dae Young; Jung, Hyo Young; Choi, Jung Hoon; Hwang, In Koo; Seong, Je Kyung

    2016-01-01

    In this study, we investigated the effects of chronic aluminum (Al) exposure for 10 weeks on cell proliferation and neuroblast differentiation in the hippocampus of type 2 diabetic rats. Six-week-old Zucker diabetic fatty (ZDF) and Zucker lean control (ZLC) rats were selected and randomly divided into Al- and non-Al-groups. Al was administered via drinking water for 10 weeks, after which the animals were sacrificed at 16 weeks of age. ZDF rats in both Al- and non-Al-groups showed increases in body weight and blood glucose levels compared to ZLC rats. Al exposure did not significantly affect body weight, blood glucose levels or pancreatic β-cells and morphology of the pancreas in either ZLC or ZDF rats. However, exposure to Al reduced cell proliferation and neuroblast differentiation in both ZLC and ZDF rats. Exposure to Al resulted in poor development of the dendritic processes of neuroblasts in both ZLC and ZDF rats. Furthermore, onset and continuation of diabetes reduced cell proliferation and neuroblast differentiation, and Al exposure amplified reduction of these parameters. These results suggest that Al exposure via drinking water aggravates the impairment in hippocampal neurogenesis that is typically observed in type 2 diabetic animals. PMID:27051335

  6. Use of alkaline aluminum-containing waste products of industrial plants for waste-water treatment

    SciTech Connect

    Shut'ko, A.P.; Butchenko, L.I.

    1987-10-20

    The aim of this work was to investigate the coagulating power of sodium aluminate, and to determine the optimum dose of the reagent and pH range of the water being purified. A solution of sodium aluminate, 0.5 M as Al/sub 2/O/sub 3/, was used, prepared by dissolving aluminum metal in concentrated alkali solution. The pH of the solution obtained was 13.80 at 20/sub 0/, and the alkalinity, determined by titration of the sodium aluminate with 0.1 M hydrochloric acid solution with the use of bromophenol blue as indicator, was 3.75 g-eq/liter. The industrial coagulant used was spent solution from processes of chemical scouring of aluminum and its alloys, containing 40 g/liter of aluminum, with a pH of 13.86 and an alkalinity of 7.5 g-eq/liter. It was determined that the optimum doses were 60-90 mg/liter as Al/sub 2/O/sub 3/. The criteria of good coagulation were a formation, during 1 min, of coarse rapidly setting flakes of aluminum hydroxide, and a low residual aluminum content not exceeding 0.5 mg/liter.

  7. Analysis and Countermeasures of Wind Power Accommodation by Aluminum Electrolysis Pot-Lines in China

    NASA Astrophysics Data System (ADS)

    Zhang, Hongliang; Ran, Ling; He, Guixiong; Wang, Zhenyu; Li, Jie

    2017-06-01

    The unit energy consumption and its price have become the main obstacles for the future development of the aluminum electrolysis industry in China. Meanwhile, wind power is widely being abandoned because of its instability. In this study, a novel idea for wind power accommodation is proposed to achieve a win-win situation: the idea is for nearby aluminum electrolysis plants to absorb the wind power. The features of the wind power distribution and aluminum electrolysis industry are first summarized, and the concept of wind power accommodation by the aluminum industry is introduced. Then, based on the characteristics of aluminum reduction cells, the key problems, including the bus-bar status, thermal balance, and magnetohydrodynamics instabilities, are analyzed. In addition, a whole accommodation implementation plan for wind power by aluminum reduction is introduced to explain the theoretical value of accommodation, evaluation of the reduction cells, and the industrial experiment scheme. A numerical simulation of a typical scenario proves that there is large accommodation potential for the aluminum reduction cells. Aluminum electrolysis can accommodate wind power and remain stable under the proper technique and accommodation scheme, which will provide promising benefits for the aluminum plant and the wind energy plant.

  8. Analysis and Countermeasures of Wind Power Accommodation by Aluminum Electrolysis Pot-Lines in China

    NASA Astrophysics Data System (ADS)

    Zhang, Hongliang; Ran, Ling; He, Guixiong; Wang, Zhenyu; Li, Jie

    2017-10-01

    The unit energy consumption and its price have become the main obstacles for the future development of the aluminum electrolysis industry in China. Meanwhile, wind power is widely being abandoned because of its instability. In this study, a novel idea for wind power accommodation is proposed to achieve a win-win situation: the idea is for nearby aluminum electrolysis plants to absorb the wind power. The features of the wind power distribution and aluminum electrolysis industry are first summarized, and the concept of wind power accommodation by the aluminum industry is introduced. Then, based on the characteristics of aluminum reduction cells, the key problems, including the bus-bar status, thermal balance, and magnetohydrodynamics instabilities, are analyzed. In addition, a whole accommodation implementation plan for wind power by aluminum reduction is introduced to explain the theoretical value of accommodation, evaluation of the reduction cells, and the industrial experiment scheme. A numerical simulation of a typical scenario proves that there is large accommodation potential for the aluminum reduction cells. Aluminum electrolysis can accommodate wind power and remain stable under the proper technique and accommodation scheme, which will provide promising benefits for the aluminum plant and the wind energy plant.

  9. Plant adaptation to acid soils: the molecular basis for crop aluminum resistance

    USDA-ARS?s Scientific Manuscript database

    Aluminum (Al) toxicity on acid soils is a significant limitation to crop production worldwide, as approximately 50% of the world’s potentially arable soils are acidic. Because acid soils are such an important constraint to agriculture, understanding the mechanisms and genes conferring resistance to ...

  10. Transformation of plant residues in the soil of a zone exposed to emissions from an aluminum smelter

    NASA Astrophysics Data System (ADS)

    Evdokimova, G. A.; Pereverzev, V. N.; Mozgova, N. P.

    2013-08-01

    The decomposition intensity and the changes in the chemical composition of plant residues (birch leaves and pine needles) were studied in forest podzols in the zone exposed to the emissions from the Kandalaksha aluminum smelter (Murmansk oblast). The stationary test plots were placed at distances of 2 and 50 km from the pollution source. The intensity of decomposition of the plant residues weakly correlated with the degree of the soil contamination. The differences in the decomposition rates and the composition of the residues were insignificant and statistically unreliable or absent. The composition of the plant residues affected these processes to a greater extent. The changes in the chemical composition of the plant residues correlated with the biomass of bacteria and fungi. The peak of their productivity was observed during the first year of the decomposition of the plant residues. During this year, the plant residues lost about 50% of their mass, and the biomasses of bacteria and fungi increased by 2-4 and 8-13 times, respectively. In the prokaryotic part of the microbial community, the portion of actinobateria increased; in the fungal community, the portion of dark-pigmented mycelium became higher.

  11. Strategies for emission reduction from thermal power plants.

    PubMed

    Prisyazhniuk, Vitaly A

    2006-07-01

    Major polluters of man's environment are thermal power stations (TPS) and power plants, which discharge into the atmosphere the basic product of carbon fuel combustion, CO2, which results in a build-up of the greenhouse effect and global warm-up of our planet's climate. This paper is intended to show that the way to attain environmental safety of the TPS and to abide by the decisions of the Kyoto Protocol lies in raising the efficiency of the heat power stations and reducing their fuel consumption by using nonconventional thermal cycles. Certain equations have been derived to define the quantitative interrelationship between the growth of efficiency of the TPS, decrease in fuel consumption and reduction of discharge of dust, fuel combustion gases, and heat into the environment. New ideas and new technological approaches that result in raising the efficiency of the TPS are briefly covered: magneto-hydrodynamic resonance, the Kalina cycle, and utilizing the ambient heat by using, as the working medium, low-boiling substances.

  12. DOWNSTREAM IMPACTS OF SLUDGE MASS REDUCTION VIA ALUMINUM DISSOLUTION ON DWPF PROCESSING OF SAVANNAH RIVER SITE HIGH LEVEL WASTE - 9382

    SciTech Connect

    Pareizs, J; Cj Bannochie, C; Michael Hay, M; Daniel McCabe, D

    2009-01-14

    The SRS sludge that was to become a major fraction of Sludge Batch 5 (SB5) for the Defense Waste Processing Facility (DWPF) contained a large fraction of H-Modified PUREX (HM) sludge, containing a large fraction of aluminum compounds that could adversely impact the processing and increase the vitrified waste volume. It is beneficial to reduce the non-radioactive fraction of the sludge to minimize the number of glass waste canisters that must be sent to a Federal Repository. Removal of aluminum compounds, such as boehmite and gibbsite, from sludge can be performed with the addition of NaOH solution and heating the sludge for several days. Preparation of SB5 involved adding sodium hydroxide directly to the waste tank and heating the contents to a moderate temperature through slurry pump operation to remove a fraction of this aluminum. The Savannah River National Laboratory (SRNL) was tasked with demonstrating this process on actual tank waste sludge in our Shielded Cells Facility. This paper evaluates some of the impacts of aluminum dissolution on sludge washing and DWPF processing by comparing sludge processing with and without aluminum dissolution. It was necessary to demonstrate these steps to ensure that the aluminum removal process would not adversely impact the chemical and physical properties of the sludge which could result in slower processing or process upsets in the DWPF.

  13. Aluminum Carbothermic Technology

    SciTech Connect

    Bruno, Marshall J.

    2005-03-31

    This report documents the non-proprietary research and development conducted on the Aluminum Carbothermic Technology (ACT) project from contract inception on July 01, 2000 to termination on December 31, 2004. The objectives of the program were to demonstrate the technical and economic feasibility of a new carbothermic process for producing commercial grade aluminum, designated as the ''Advanced Reactor Process'' (ARP). The scope of the program ranged from fundamental research through small scale laboratory experiments (65 kW power input) to larger scale test modules at up to 1600 kW power input. The tasks included work on four components of the process, Stages 1 and 2 of the reactor, vapor recovery and metal alloy decarbonization; development of computer models; and economic analyses of capital and operating costs. Justification for developing a new, carbothermic route to aluminum production is defined by the potential benefits in reduced energy, lower costs and more favorable environmental characteristics than the conventional Hall-Heroult process presently used by the industry. The estimated metrics for these advantages include energy rates at approximately 10 kWh/kg Al (versus over 13 kWh/kg Al for Hall-Heroult), capital costs as low as $1250 per MTY (versus 4,000 per MTY for Hall-Heroult), operating cost reductions of over 10%, and up to 37% reduction in CO2 emissions for fossil-fuel power plants. Realization of these benefits would be critical to sustaining the US aluminum industries position as a global leader in primary aluminum production. One very attractive incentive for ARP is its perceived ability to cost effectively produce metal over a range of smelter sizes, not feasible for Hall-Heroult plants which must be large, 240,000 TPY or more, to be economical. Lower capacity stand alone carbothermic smelters could be utilized to supply molten metal at fabrication facilities similar to the mini-mill concept employed by the steel industry. Major

  14. Reduction of Carbon Footprint and Energy Efficiency Improvement in Aluminum Production by Use of Novel Wireless Instrumentation Integrated with Mathematical Modeling

    SciTech Connect

    James W. Evans

    2012-04-11

    The work addressed the greenhouse gas emission and electrical energy consumption of the aluminum industry. The objective was to provide a means for reducing both through the application of wireless instrumentation, coupled to mathematical modeling. Worldwide the aluminum industry consumes more electrical energy than all activities in many major countries (e.g. the UK) and emits more greenhouse gasses (e.g. than France). Most of these excesses are in the 'primary production' of aluminum; that is the conversion of aluminum oxide to metal in large electrolytic cells operating at hundreds of thousands of amps. An industry-specific GHG emission has been the focus of the work. The electrolytic cells periodically, but at irregular intervals, experience an upset condition known as an 'anode effect'. During such anode effects the cells emit fluorinated hydrocarbons (PFCs, which have a high global warming potential) at a rate far greater than in normal operation. Therefore curbing anode effects will reduce GHG emissions. Prior work had indicated that the distribution of electrical current within the cell experiences significant shifts in the minutes before an anode effect. The thrust of the present work was to develop technology that could detect and report this early warning of an anode effect so that the control computer could minimize GHG emissions. A system was developed to achieve this goal and, in collaboration with Alcoa, was tested on two cells at an Alcoa plant in Malaga, Washington. The project has also pointed to the possibility of additional improvements that could result from the work. Notable among these is an improvement in efficiency that could result in an increase in cell output at little extra operating cost. Prospects for commercialization have emerged in the form of purchase orders for further installations. The work has demonstrated that a system for monitoring the current of individual anodes in an aluminum cell is practical. Furthermore the system has

  15. Hydrogen sulfide alleviates the aluminum-induced changes in Brassica napus as revealed by physiochemical and ultrastructural study of plant.

    PubMed

    Ali, Basharat; Qian, Ping; Sun, Rui; Farooq, Muhammad A; Gill, Rafaqat A; Wang, Jian; Azam, Muhammad; Zhou, Weijun

    2015-02-01

    In the present study, ameliorating role of hydrogen sulfide (H2S) in oilseed rape (Brassica napus L.) was studied with or without application of H2S donor sodium hydrosulfide (NaHS) (0.3 mM) in hydroponic conditions under three levels (0, 0.1 and 0.3 mM) of aluminum (Al). Results showed that addition of H2S significantly improved the plant growth, photosynthetic gas exchange, and nutrients concentration in the leaves and roots of B. napus plants under Al stress. Exogenously applied H2S significantly lowered the Al concentration in different plant parts, and reduced the production of malondialdehyde and reactive oxygen species by improving antioxidant enzyme activities in the leaves and roots under Al stress. Moreover, the present study indicated that exogenously applied H2S improved the cell structure and displayed clean mesophyll and root tip cells. The chloroplast with well-developed thylakoid membranes could be observed in the micrographs. Under the combined application of H2S and Al, a number of modifications could be observed in root tip cell, such as mitochondria, endoplasmic reticulum, and golgi bodies. Thus, it can be concluded that exogenous application of H2S under Al stress improved the plant growth, photosynthetic parameters, elements concentration, and biochemical and ultrastructural changes in leaves and roots of B. napus.

  16. The impact of plants on the reduction of volatile organic compounds in a small space.

    PubMed

    Song, Jeong-Eun; Kim, Yong-Shik; Sohn, Jang-Yeul

    2007-11-01

    This study aims at examining the reduction of indoor air contaminants by plants placed in an indoor space. Field measurements were performed using Aglaonema brevispathum, Pachira aquatica, and Ficus benjamiana, which were verified as air-purifying plants by NASA. Three conditions for the amount of plants and positions were used in two separate rooms whose dimensions are identical. The concentration of Volatile Organic Compounds (VOCs) was monitored three hours after the plants were placed and three days after the plants were placed. The variations of concentration of Benzene, Toluene, Etylbenzene, and Xylene (BTEX), as well as Formaldehyde, which are all known as the major elements of Volatile Organic Compounds were monitored. The amount of reduction in concentration of Toluene and Formaldehyde was monitored 3 hours and 3 days after the plants were placed in the space. The reduction in the concentration of Benzene, Toluene, Etylbenzene, Xylene, and Formaldehyde was significantly greater when plants were present. When plants were placed near a window, the reduction of concentration was greater. The more plants were used, the more a reduction of indoor air contaminants occurred. The effect of reducing the concentration of air contaminants increased when the amount of plants increased, and when the plants were placed in sunny area. The concentration of Toluene was reduced by 45.6 microg/m(3) when 10% of the model space was occupied by Aglaonema brevispathum.

  17. Cost Reductions for Wastewater Treatment Utilizing Water Management at Holston Army Ammunition Plant

    DTIC Science & Technology

    1976-05-01

    HOLSTON ARMY AMMUNITION PLANT DARCOM INTERN TRAINING CENTER MAY 1976 .:15914414 Report DARCOM-ITC-02-;08-76-201 COST REDUCTIONS FOR WASTEWATER...TREATIMENT UTILIZING WATER MANAGEMENT AT HOLSTON ARMY AMMUNITION PLANT Dennis J. Kravec Product/Production Graduate Engineering Program DARCOM Intern...number) This ?study examines the cost reductions obtained by using water management te6hniques at Holston Army Ammunition Plant . It compares the

  18. Production of aluminum-silicon alloy and ferrosilicon and commercial-purity aluminum by the direct-reduction process. Third annual technical report, 1980 January 1-1980 December 31

    SciTech Connect

    Bruno, M.J.

    1981-01-01

    Progress on the program to demonstrate the technical feasibility of a pilot-sized Direct Reduction Process for producing aluminium and aluminium-silicon alloy is reported for Phase C. Progress is reported on reduction including the following tasks: supply burden material; burden beneficiation; effects of pilot operating parameters; pilot modifications; reactor scale-up design; calculating heat and mass balance; processing mathematical modeling; effects of process variables; information on supportive analytical, phase identification, and mechanical engineering data. Progress on alloy purification is reported in the following tasks: pilot unit installation; effects of pilot operating parameters; pilot unit modifications; and supportive mechanical engineering. Progress on purification to commercial grade aluminum is reported on: pilot unit installation; effects of pilot operating parameters; pilot unit modifications; support pilot operations; and supportive expended man-hours. Plans for Phase D are noted. (MCW)

  19. Beryllium in exhaled breath condensate as a biomarker of occupational exposure in a primary aluminum production plant.

    PubMed

    Hulo, Sébastien; Radauceanu, Anca; Chérot-Kornobis, Nathalie; Howsam, Mike; Vacchina, Véronique; De Broucker, Virginie; Rousset, Davy; Grzebyk, Michel; Dziurla, Mathieu; Sobaszek, Annie; Edme, Jean-Louis

    2016-01-01

    Low beryllium exposure can induce pulmonary granulomatosis, so called berylliosis. For occupational health monitoring, it is more relevant to assess the internal dose of Be received by the lungs than urinary or atmospheric Be. Exhaled breath condensate (EBC) is a matrix collected non-invasively that derives from the airway lining fluid. EBC beryllium (Be) levels were evaluated as a marker of occupational exposure in a primary aluminum production plant. We collected urine and EBC from controls and workers recently exposed to beryllium in the pot room and the anode repair sectors, and calculated a cumulative beryllium exposure index (CBEI) summing the number of years of employment in each task and multiplying by the estimated average beryllium exposure for the task. Concentrations of beryllium and aluminum were measured in EBC (Be-EBC and Al-EBC) and in urine (Be-U and Al-U) by ICP-MS. We have shown that it was possible to measure Be and Al in workers' EBC. Compared with controls and after adjustment for smoking status, levels of Be-EBC and Al-EBC were higher in pot room workers and exposed subjects, respectively. Due to its relationship with CBEI, but not with Be-U, it appears that Be-EBC could be a promising marker of occupational exposure and provide additional toxicokinetic information in occupational health studies. Copyright © 2015 Elsevier GmbH. All rights reserved.

  20. Anodized aluminum wire as a solid-phase microextraction fiber for rapid determination of volatile constituents in medicinal plant.

    PubMed

    Gholivand, Mohammad Bagher; Piryaei, Marzieh; Abolghasemi, Mir Mahdi

    2011-09-02

    Headspace solid phase microextraction using anodized aluminum fiber in combination with capillary GC-MS was utilized as monitoring technique for the collection and detection of the volatile compounds of Echinophora platyloba DC. Experimental parameters, including the sample weight, extraction temperature, extraction time and humidity effect, desorption time and desorption temperature were examined and optimized. Using HS-SPME followed by GC-MS, 53 compounds were separated and identified in E. platyloba DC, which mainly included E-β ocimene (47.63%), R-D-decalactone (13.28%), α-pinene (7.43%) and nonane (6.71%). Compared with hydrodistillation (HD), HS-SPME, provides the advantages of a small amount of sample, timesaving, simplicity and cheapness. To the best of our knowledge, this is the first report on using anodized aluminum fiber in solid-phase microextraction coupled to headspace for the investigation of volatile fraction of medicinal plant. Copyright © 2011 Elsevier B.V. All rights reserved.

  1. Final report on the application of chaos theory to an alumina sensor for aluminum reduction cells. Inert Electrodes Program

    SciTech Connect

    Williford, R.E.; Windisch, C.F. Jr.

    1992-03-01

    Four chaos-related digital signal analysis (DSA) methods were applied to the analysis of voltage and current signals collected from aluminum electrolysis cells. Two separate data bases were analyzed: bench-scale laboratory experiments and a pilot-scale test. The objective was to assess the feasibility of using these types of data and analysis methods as the basis for a non-intrusive sensor to measure the alumina content in the electrolysis bath. This was the first time chaos theory approaches have been employed to analyze aluminum electrolysis cells.

  2. Energy Assessment Helps Kaiser Aluminum Save Energy and Improve Productivity; DOE Software Adopted as Standard for Analyzing Plant Process Heating Systems Company-Wide

    SciTech Connect

    Not Available

    2008-07-01

    This case study describes how the Kaiser Aluminum plant in Sherman, Texas, achieved annual savings of $360,000 and 45,000 MMBtu, and improved furnace energy intensity by 11.1% after receiving a DOE Save Energy Now energy assessment and implementing recommendations to improve the efficiency of its process heating system.

  3. Reduction in waste load from a meat processing plant: Beef

    SciTech Connect

    1986-10-31

    ;Contents: Introduction (Randolph Packing Company, Meat Plant Wastewaters, Slaughterhouses, Packing Houses, Sources of Wastewater, Secondary Manufacturing Processes, An Example of Water Conservation and Waste Control, Water Conservation Program); Plant Review and Survey (Survey for Product Losses and Wastes, Water Use and Waste Load, Wastewater Discharge Limitations and Costs); Waste Centers, Changes, Costs and Results (In-Plant Control Measures, Water Conservation, Recovery Products, By-Products and Reducing Waste Load, Blood Conservation, Paunch Handling and Processing, Summary of Process Changes, Pretreatment, Advantages and Disadvantages of Pretreatment, Pretreatment Systems).

  4. Red mud a byproduct of aluminum production contains soluble vanadium that causes genotoxic and cytotoxic effects in higher plants.

    PubMed

    Mišík, Miroslav; Burke, Ian T; Reismüller, Matthias; Pichler, Clemens; Rainer, Bernhard; Mišíková, Katarina; Mayes, William M; Knasmueller, Siegfried

    2014-09-15

    Red mud (RM) is a byproduct of aluminum production; worldwide between 70 and 120 million tons is produced annually. We analyzed RM which was released in the course of the Kolontar disaster in Hungary into the environment in acute and genotoxicity experiments with plants which are widely used for environmental monitoring. We detected induction of micronuclei which reflect chromosomal damage in tetrads of Tradescantia and in root cells of Allium as well as retardation of root growth with contaminated soils and leachates. Chemical analyses showed that RM contains metals, in particular high concentrations of vanadium. Follow-up experiments indicated that vanadate causes the effects in the plants. This compound causes also in humans DNA damage and positive results were obtained in carcinogenicity studies. Since it was found also in RM from other production sites our findings indicate that its release in the environment is a global problem which should be studied in more detail. Our findings indicate that the red mud causes genotoxic effect in plants probably due to the presence of vanadate which is contained at high concentrations in the residue. Copyright © 2014. Published by Elsevier B.V.

  5. Enantioselective Reduction by Crude Plant Parts: Reduction of Benzofuran-2-yl Methyl Ketone with Carrot ("Daucus carota") Bits

    ERIC Educational Resources Information Center

    Ravia, Silvana; Gamenara, Daniela; Schapiro, Valeria; Bellomo, Ana; Adum, Jorge; Seoane, Gustavo; Gonzalez, David

    2006-01-01

    The use of biocatalysis and biotransformations are important tools in green chemistry. The enantioselective reduction of a ketone by crude plant parts, using carrot ("Daucus carota") as the reducing agent is presented. The experiment introduces an example of a green chemistry procedure that can be tailored to fit in a regular laboratory session.…

  6. Enantioselective Reduction by Crude Plant Parts: Reduction of Benzofuran-2-yl Methyl Ketone with Carrot ("Daucus carota") Bits

    ERIC Educational Resources Information Center

    Ravia, Silvana; Gamenara, Daniela; Schapiro, Valeria; Bellomo, Ana; Adum, Jorge; Seoane, Gustavo; Gonzalez, David

    2006-01-01

    The use of biocatalysis and biotransformations are important tools in green chemistry. The enantioselective reduction of a ketone by crude plant parts, using carrot ("Daucus carota") as the reducing agent is presented. The experiment introduces an example of a green chemistry procedure that can be tailored to fit in a regular laboratory session.…

  7. Overexpression of a peroxidase gene (AtPrx64) of Arabidopsis thaliana in tobacco improves plant's tolerance to aluminum stress.

    PubMed

    Wu, Yuanshuang; Yang, Zhili; How, Jingyi; Xu, Huini; Chen, Limei; Li, Kunzhi

    2017-08-16

    AtPrx64 is one of the peroxidases gene up-regulated in Al stress and has some functions in the formation of plant second cell wall. Its overexpression may improve plant tolerance to Al by some ways. Studies on its function under Al stress may help us to understand the mechanism of plant tolerance to Al stress. In Arabidopsis thaliana, the expressions of some genes (AtPrxs) encoding class III plant peroxidases have been found to be either up-regulated or down-regulated under aluminum (Al) stress. Among 73 genes that encode AtPrxs in Arabidopsis, AtPrx64 is always up-regulated by Al stress, suggesting this gene plays protective roles in response to such stress. In this study, transgenic tobacco plants were generated to examine the effects of overexpressing of AtPrx64 gene on the tolerance to Al stress. The results showed that overexpression of AtPrx64 gene increased the root growth and reduced the accumulation of Al and ROS in the roots. Compared with wild type controls, transgenic tobaccos had much less soluble proteins and malondialdehyde in roots and much more root citrate exudation. The activity of plasma membrane (PM) H(+)-ATPase, the phosphorylation of PM H(+)-ATPase and its interaction with 14-3-3 proteins increased in transgenic tobaccos; moreover, the content of lignin in root tips also increased. Taken together, these results showed that overexpression of AtPrx64 gene might enhance the tolerance of tobacco to Al stress.

  8. Aluminum-induced 1-->3-beta-D-glucan inhibits cell-to-cell trafficking of molecules through plasmodesmata. A new mechanism of aluminum toxicity in plants.

    PubMed

    Sivaguru, M; Fujiwara, T; Samaj, J; Baluska, F; Yang, Z; Osawa, H; Maeda, T; Mori, T; Volkmann, D; Matsumoto, H

    2000-11-01

    Symplastic intercellular transport in plants is achieved by plasmodesmata (PD). These cytoplasmic channels are well known to interconnect plant cells to facilitate intercellular movement of water, nutrients, and signaling molecules including hormones. However, it is not known whether Al may affect this cell-to-cell transport process, which is a critical feature for roots as organs of nutrient/water uptake. We have microinjected the dye lucifer yellow carbohydrazide into peripheral root cells of an Al-sensitive wheat (Triticum aestivum cv Scout 66) either before or after Al treatment and followed the cell-to-cell dye-coupling through PD. Here we show that the Al-induced root growth inhibition is closely associated with the Al-induced blockage of cell-to-cell dye coupling. Immunofluorescence combined with immuno-electron microscopic techniques using monoclonal antibodies against 1-->3-beta-D-glucan (callose) revealed circumstantial evidence that Al-induced callose deposition at PD may responsible for this blockage of symplastic transport. Use of 2-deoxy-D-glucose, a callose synthesis inhibitor, allowed us to demonstrate that a reduction in callose particles correlated well with the improved dye-coupling and reduced root growth inhibition. While assessing the tissue specificity of this Al effect, comparable responses were obtained from the dye-coupling pattern in tobacco (Nicotiana tabacum) mesophyll cells. Analyses of the Al-induced expression of PD-associated proteins, such as calreticulin and unconventional myosin VIII, showed enhanced fluorescence and co-localizations with callose deposits. These results suggest that Al-signal mediated localized alterations to calcium homeostasis may drive callose formation and PD closure. Our data demonstrate that extracellular Al-induced callose deposition at PD could effectively block symplastic transport and communication in higher plants.

  9. Effect of Aluminum Treatment on Proteomes of Radicles of Seeds Derived from Al-Treated Tomato Plants

    PubMed Central

    Okekeogbu, Ikenna; Ye, Zhujia; Sangireddy, Sasikiran Reddy; Li, Hui; Bhatti, Sarabjit; Hui, Dafeng; Zhou, Suping; Howe, Kevin J.; Fish, Tara; Yang, Yong; Thannhauser, Theodore W.

    2014-01-01

    Aluminum (Al) toxicity is a major constraint to plant growth and crop yield in acid soils. Tomato cultivars are especially susceptible to excessive Al3+ accumulated in the root zone. In this study, tomato plants were grown in a hydroponic culture system supplemented with 50 µM AlK(SO4)2. Seeds harvested from Al-treated plants contained a significantly higher Al content than those grown in the control hydroponic solution. In this study, these Al-enriched tomato seeds (harvested from Al-treated tomato plants) were germinated in 50 µM AlK(SO4)2 solution in a homopiperazine-1,4-bis(2-ethanesulfonic acid) buffer (pH 4.0), and the control solution which contained the buffer only. Proteomes of radicles were analyzed quantitatively by mass spectrometry employing isobaric tags for relative and absolute quantitation (iTRAQ®). The proteins identified were assigned to molecular functional groups and cellular metabolic pathways using MapMan. Among the proteins whose abundance levels changed significantly were: a number of transcription factors; proteins regulating gene silencing and programmed cell death; proteins in primary and secondary signaling pathways, including phytohormone signaling and proteins for enhancing tolerance to abiotic and biotic stress. Among the metabolic pathways, enzymes in glycolysis and fermentation and sucrolytic pathways were repressed. Secondary metabolic pathways including the mevalonate pathway and lignin biosynthesis were induced. Biological reactions in mitochondria seem to be induced due to an increase in the abundance level of mitochondrial ribosomes and enzymes in the TCA cycle, electron transport chains and ATP synthesis. PMID:28250376

  10. Reduction of Atmospheric Pollution by Sulphuric Acid Plants,

    DTIC Science & Technology

    1980-01-29

    D. Stanciu, T. Ciobanu English pages: 10 Source: Revista de Chimie , Vol. 28, Nr. 3, March 1977, pp. 263-267 Country of Origin: Romania Translated by...process In contact sulphuric acid plants. The former process with licences patented In other countries as well, Is based on the commonly known

  11. [Processes of adaptogenesis and heart remodelling in workers of electrolysis workshops in aluminum plants].

    PubMed

    Khasanova, G N; Oranskiĭ, I E; Roslaia, N A

    2010-01-01

    Workers in electrolysis workshops of aluminium plants demonstrate changes in intracardial hemodynamics and left ventricle diastolic function, heart remodelling to concentric and excentric hypertrophy, more in individuals with chronic occupational fluorine intoxication.

  12. Prevention of PCDD/F formation and minimization of their emission at the stack of a secondary aluminum casting plant.

    PubMed

    Pitea, Demetrio; Bortolami, Michele; Collina, Elena; Cortili, Gabriele; Franzoni, Francesco; Lasagni, Marina; Piccinelli, Elsa

    2008-10-01

    Results of an extensive 5 year study on a full-scale plant with the specific aim to investigate polychlorinated dibenzo-p-dioxin (PCDD) and polychlorinated dibenzo furan (PCDF) formation and release in a secondary aluminum casting plant are reported. PCDD and PCDF concentrations were evaluated for all the gaseous and solid streams (no liquid stream was present) as well as for the flue gas upstream and downstream of every single unit of the flue gas cleaning system. The study highlights PCDD and PCDF formation particularly in the narrow 320-360 degrees C range. To prevent formation reactions and/or minimize PCDD and PCDF concentration at the stack, effects of the fabric filter substitution, a quenching chamber and a postcombustor installation together with working conditions are investigated. The flue gas cleaning system results in PCDD and PCDF emission at stack of 0.1-0.2 ng I-TEQ/N m3 and in a mass flow of 250-550 nmol/h. The total PCDD and PCDF release into the environment is 0.06 g I-TEQ/yr and the corresponding emission factor, 0.35 microg I-TEQ/ton. It is shown that the global effects of the technological innovation on the reaction mechanisms are the prevention of PCDD/F formation by de novo synthesis and the minimization of their emission.

  13. Amelioration of iron toxicity: A mechanism for aluminum-induced growth stimulation in tea plants.

    PubMed

    Hajiboland, Roghieh; Barceló, Juan; Poschenrieder, Charlotte; Tolrà, Roser

    2013-11-01

    Tea plants (Camellia sinensis) are well adapted to acid soils with high Al availability. These plants not only accumulate high leaf Al concentrations, but also respond to Al with growth stimulation. Decreased oxidative stress has been associated with this effect. Why tea plants not exposed to Al suffer from oxidative stress has not been clarified. In this study, hydroponically grown tea plants treated with 0 to 300 μM Al were analyzed for growth, Al and Fe accumulation, and Al distribution by means of morin and hematoxylin staining. Roots of control plants stained black with hematoxylin. This indicates the formation of a Fe-hematoxylin complex. Young leaves of controls accumulated more than 1000 mg Fe kg(-1) dry weight. This concentration is above the Fe-toxicity threshold in most species. Supply of Al stimulated growth and reduced Fe uptake and transport. These results indicate that Al-induced growth stimulation might be due to alleviation of a latent Fe toxicity occurring in tea plants without Al supply.

  14. Energy-Saving Melting and Revert Reduction Technology (E-SMARRT): Lost Foam Thin Wall - Feasibility of Producing Lost Foam Castings in Aluminum and Magnesium Based Alloys

    SciTech Connect

    Fasoyinu, Yemi; Griffin, John A.

    2014-03-31

    With the increased emphasis on vehicle weight reduction, production of near-net shape components by lost foam casting will make significant inroad into the next-generation of engineering component designs. The lost foam casting process is a cost effective method for producing complex castings using an expandable polystyrene pattern and un-bonded sand. The use of un-bonded molding media in the lost foam process will impose less constraint on the solidifying casting, making hot tearing less prevalent. This is especially true in Al-Mg and Al-Cu alloy systems that are prone to hot tearing when poured in rigid molds partially due to their long freezing range. Some of the unique advantages of using the lost foam casting process are closer dimensional tolerance, higher casting yield, and the elimination of sand cores and binders. Most of the aluminum alloys poured using the lost foam process are based on the Al-Si system. Very limited research work has been performed with Al-Mg and Al-Cu type alloys. With the increased emphasis on vehicle weight reduction, and given the high-strength-to-weight-ratio of magnesium, significant weight savings can be achieved by casting thin-wall (≤ 3 mm) engineering components from both aluminum- and magnesium-base alloys.

  15. The Aluminum Smelting Process

    PubMed Central

    2014-01-01

    This introduction to the industrial primary aluminum production process presents a short description of the electrolytic reduction technology, the history of aluminum, and the importance of this metal and its production process to modern society. Aluminum's special qualities have enabled advances in technologies coupled with energy and cost savings. Aircraft capabilities have been greatly enhanced, and increases in size and capacity are made possible by advances in aluminum technology. The metal's flexibility for shaping and extruding has led to architectural advances in energy-saving building construction. The high strength-to-weight ratio has meant a substantial reduction in energy consumption for trucks and other vehicles. The aluminum industry is therefore a pivotal one for ecological sustainability and strategic for technological development. PMID:24806722

  16. New plant and controller order reduction results with weighted balancing

    NASA Technical Reports Server (NTRS)

    Newman, Brett; Schmidt, David K.

    1991-01-01

    A frequency-response error analysis for frequency-weighted internally balanced (FWIB) truncation is extended and an exact error bound for a case of order reduction by one state is presented. An approximate error bound for a general case of order reduction by more than one state, assuming that only small controllability-observability measures are truncated, is considered. FWIB residualization is presented, and it is shown that a frequency-response error analysis yields results similar to those found for FWIB truncation. It is concluded that FWIB truncation and residualization can be used in a coordinated manner consistent with classical truncation and residualization in order to obtain accuracy higher than that possible from either technique used alone.

  17. Central Plant Optimization for Waste Energy Reduction (CPOWER)

    DTIC Science & Technology

    2016-12-01

    commands at the plant. Since there is a long start up and shutdown period (the boiler should be well warmed before turning on the gas, to avoid...is a long start up and shutdown period (the boiler should be well warmed before turning on the gas, to avoid thermal stress problems), the local...CPOWER operator manual (see Appendices E and F). Since there is a long start up and shutdown period (the boiler should be well warmed before turning on

  18. Production of aluminum-silicon alloy and ferrosilicon and commercial purity aluminum by the direct reduction process. First interim technical report, Phase D, January 1-March 31, 1981

    SciTech Connect

    Bruno, M.J.

    1981-04-01

    Operation of the bench AF-reactor on burden with all reducing carbon exterior to the ore pellet resulted in low metal alloy product yields and prematurely terminated runs, indicating the need for intimate contact between alumina and carbon to produce oxycarbide liquid prior to reaction with solid silicon carbide. Carbon solubility tests made on 60Al-40Si alloys at 2200/sup 0/C in graphite crucibles indicated continued reaction to form SiC for one hour. Efficiency of reduction to SiC ranged from 68 to 100%. The A-C two-electrode submerged arc reactor pilot, SAR-II, was successfully operated on both alumina-clay-coke and alumina-silicon carbide-coke (from the VSR prereduction) burdens. Metal alloy was produced and tapped in each of four runs. The pilot crystallizer was operated to evalute the two-stage (stop and go) crystallization technique on obtaining high yields of Al in Al-Si eutectic, with a limit of 1.0% Fe and 0.1% Ti in the alloy product. 18 figures, 19 tables. (DLC)

  19. Cost-Effective Consolidation of Fine Aluminum Scrap for Increased Remelting Effieciency

    SciTech Connect

    William Van Geertruyden

    2005-09-22

    The main objective of this research was to develop a new re-melting process for fine or light gauge aluminum scrap products that exhibits dramatic improvements in energy efficiency. Light gauge aluminum scrap in the form of chips, turnings, and borings has historically been underutilized in the aluminum recycling process due to its high surface area to volume ratio resulting in low melt recovery. Laboratory scale consolidation experiments were performed using loose aluminum powder as a modeling material as well as shredded aluminum wire scrap. The processing parameters necessary to create consolidated aluminum material were determined. Additionally, re-melting experiments using consolidated and unconsolidated aluminum powder confirmed the hypothesis that metal recovery using consolidated material will significantly improve by as much as 20%. Based on this research, it is estimated that approximately 495 billion Btu/year can be saved by implementation of this technology in one domestic aluminum rolling plant alone. The energy savings are realized by substituting aluminum scrap for primary aluminum, which requires large amounts of energy to produce. While there will be an initial capital investment, companies will benefit from the reduction of dependence on primary aluminum thus saving considerable costs. Additionally, the technology will allow companies to maintain in-house alloy scrap, rather than purchasing from other vendors and eliminate the need to discard the light gauge scrap to landfills.

  20. State of the art review of radioactive waste volume reduction techniques for commercial nuclear power plants

    SciTech Connect

    Not Available

    1980-04-01

    A review is made of the state of the art of volume reduction techniques for low level liquid and solid radioactive wastes produced as a result of: (1) operation of commercial nuclear power plants, (2) storage of spent fuel in away-from-reactor facilities, and (3) decontamination/decommissioning of commercial nuclear power plants. The types of wastes and their chemical, physical, and radiological characteristics are identified. Methods used by industry for processing radioactive wastes are reviewed and compared to the new techniques for processing and reducing the volume of radioactive wastes. A detailed system description and report on operating experiences follow for each of the new volume reduction techniques. In addition, descriptions of volume reduction methods presently under development are provided. The Appendix records data collected during site surveys of vendor facilities and operating power plants. A Bibliography is provided for each of the various volume reduction techniques discussed in the report.

  1. Reduction of operations and maintenance costs at geothermal power plants

    SciTech Connect

    Bruton, C.J.; Stevens, C.G.; Rard, J.A.; Kasameyer, P.W.

    1997-12-31

    To reduce chemical costs at geothermal power plants, we are investigating: (a) improved chemical processes associated with H{sub 2}S abatement techniques, and (b) the use of cross dispersive infrared spectrometry to monitor accurately, reliably, and continuously H{sub 2}S emissions from cooling towers. The latter is a new type of infrared optical technology developed by LLNL for non-proliferation verification. Initial work is focused at The Geysers in cooperation with Pacific Gas and Electric. Methods for deploying the spectrometer on-site at The Geysers are being developed. Chemical analysis of solutions involved in H{sub 2}S abatement technologies is continuing to isolate the chemical forms of sulfur produced.

  2. CARB approves smog reduction plant for Southern California

    SciTech Connect

    Not Available

    1989-10-01

    The California Air Resources Board on August 15 approved a long range plan for bringing Southern California, the smoggiest region in the country, into compliance with federal air quality standards over the next 18 years. The plan is a combination of land use and transportation measures to be administered through local government (SCAG), controls on non-automotive county South Coast Air Quality Management District, and the nation's strictest standards on automotive emissions and fuel quality adopted by the State ARB. To meet the health standards in the four-county South Coast Air Basin, the plan intends to reduce smog-forming nitrogen oxides and hydrocarbon by 65 and 84 percent, respectively, from current levels. In addition, carbon monoxide levels are to be cut 42 percent by the year 2007. Approximately 75 measures in the plan, regarding industrial emission controls and changes in land use policies, transportation systems and energy use, are expected to achieve half of those reductions, or 372 tons per day. Most of the industrial controls are extensions of current programs or adaptations of anti-smog technology from one industrial use to another. Twenty of the measures are aimed at reducing the smog-forming potential of solvents in paints, degreasers and other types of coatings while 15 would continue reducing emissions from refineries and other aspects of petroleum production. The other half of the clean air benefits credited to the plan are the result of the Air Resources Board controls on tailpipe emissions of cars, trucks and other motor vehicles, and clean-up standards for diesel, gasoline and other fuels. Combined, the 16 ARB measures are expected to reduce smog-forming emissions by 385 tons per day and are responsible for nearly all of the carbon monoxide reductions.

  3. Soil Oxidation-Reduction in Wetlands and Its Impact on Plant Functioning

    PubMed Central

    Pezeshki, S. R.; DeLaune, R. D.

    2012-01-01

    Soil flooding in wetlands is accompanied by changes in soil physical and chemical characteristics. These changes include the lowering of soil redox potential (Eh) leading to increasing demand for oxygen within the soil profile as well as production of soil phytotoxins that are by-products of soil reduction and thus, imposing potentially severe stress on plant roots. Various methods are utilized for quantifying plant responses to reducing soil conditions that include measurement of radial oxygen transport, plant enzymatic responses, and assessment of anatomical/morphological changes. However, the chemical properties and reducing nature of soil environment in which plant roots are grown, including oxygen demand, and other associated processes that occur in wetland soils, pose a challenge to evaluation and comparison of plant responses that are reported in the literature. This review emphasizes soil-plant interactions in wetlands, drawing attention to the importance of quantifying the intensity and capacity of soil reduction for proper evaluation of wetland plant responses, particularly at the process and whole-plant levels. Furthermore, while root oxygen-deficiency may partially account for plant stress responses, the importance of soil phytotoxins, produced as by-products of low soil Eh conditions, is discussed and the need for development of methods to allow differentiation of plant responses to reduced or anaerobic soil conditions vs. soil phytotoxins is emphasized. PMID:24832223

  4. Physicochemical properties of magnesium aluminum silicate (smectone) gels prepared using electrolytic-reduction ion water (2): Effects of various salts on the phase diagram.

    PubMed

    Okajima, Masahiro; Shimokawa, Ken-ichi; Ishii, Fumiyoshi

    2009-09-01

    We produced gels using electrolytic-reduction ion water and magnesium aluminum silicates (smectone), and evaluated in detail gel properties in the presence of various types of salt (NaCl, KCl, CaCl(2), MgCl(2), and AlCl(3)). Each salt was added to deionized-distilled water or electrolytic-reduction ion water, and phase diagrams for the smectone concentration (2.0-4.0%) were produced. The areas of the three phases of smectone (gel, sol, and separation) at each salt concentration were expressed as percentages of the total area. As a result, uni- and polyvalent cations (excluding Ca(2+) ions) affected the stability of gels produced using electrolytic-reduction ion water, and, particularly, univalent cations (Na(+), K(+)) markedly improved gel stability. Using electrolytic-reduction ion water as a dispersal medium, drug delivery systems (DDS) that can maintain the gelling state can be prepared. Thus, gel preparations with maintained functions or controlled-release transdermal drugs can be obtained.

  5. Tonoplast- and Plasma Membrane-Localized Aquaporin-Family Transporters in Blue Hydrangea Sepals of Aluminum Hyperaccumulating Plant

    PubMed Central

    Negishi, Takashi; Oshima, Kenshiro; Hattori, Masahira; Kanai, Masatake; Mano, Shoji; Nishimura, Mikio; Yoshida, Kumi

    2012-01-01

    Hydrangea (Hydrangea macrophylla) is tolerant of acidic soils in which toxicity generally arises from the presence of the soluble aluminum (Al) ion. When hydrangea is cultivated in acidic soil, its resulting blue sepal color is caused by the Al complex formation of anthocyanin. The concentration of vacuolar Al in blue sepal cells can reach levels in excess of approximately 15 mM, suggesting the existence of an Al-transport and/or storage system. However, until now, no Al transporter has been identified in Al hyperaccumulating plants, animals or microorganisms. To identify the transporter being responsible for Al hyperaccumulation, we prepared a cDNA library from blue sepals according to the sepal maturation stage, and then selected candidate genes using a microarray analysis and an in silico study. Here, we identified the vacuolar and plasma membrane-localized Al transporters genes vacuolar Al transporter (VALT) and plasma membrane Al transporter 1 (PALT1), respectively, which are both members of the aquaporin family. The localization of each protein was confirmed by the transient co-expression of the genes. Reverse transcription-PCR and immunoblotting results indicated that VALT and PALT1 are highly expressed in sepal tissue. The overexpression of VALT and PALT1 in Arabidopsis thaliana conferred Al-tolerance and Al-sensitivity, respectively. PMID:22952644

  6. (La1-xSrx)0.98MnO3 perovskite with A-site deficiencies toward oxygen reduction reaction in aluminum-air batteries

    NASA Astrophysics Data System (ADS)

    Xue, Yejian; Miao, He; Sun, Shanshan; Wang, Qin; Li, Shihua; Liu, Zhaoping

    2017-02-01

    The strontium doped Mn-based perovskites have been proposed as one of the best oxygen reduction reaction catalysts (ORRCs) to substitute the noble metal. However, few studies have investigated the catalytic activities of LSM with the A-site deficiencies. Here, the (La1-xSrx)0.98MnO3 (LSM) perovskites with A-site deficiencies are prepared by a modified solid-liquid method. The structure, morphology, valence state and oxygen adsorption behaviors of these LSM samples are characterized, and their catalytic activities toward ORR are studied by the rotating ring-disk electrode (RRDE) and aluminum-air battery technologies. The results show that the appropriate doping with Sr and introducing A-site stoichiometry can effectively tailor the Mn valence and increase the oxygen adsorption capacity of LSM. Among all the LSM samples in this work, the (La0.7Sr0.3)0.98MnO3 perovskite composited with 50% carbon (50%LSM30) exhibits the best ORR catalytic activity due to the excellent oxygen adsorption capacity. Also, this catalyst has much higher durability than that of commercial 20%Pt/C. Moreover, the maximum power density of the aluminum-air battery using 50%LSM30 as the ORRC can reach 191.3 mW cm-2. Our work indicates that the LSM/C composite catalysts with A-site deficiencies can be used as a promising ORRC in the metal-air batteries.

  7. Effect of Wetland Plants on the Reduction of Hexavalent Chromium in Sediments

    NASA Astrophysics Data System (ADS)

    Zazo, J. A.; Paull, J.; Jaffe, P. R.

    2007-12-01

    The effect of wetland plants (Typha latifolia and Carex lurida) on the reduction of Cr(VI) to Cr(III) at relatively low initial Cr(VI) concentrations (< 5 mg/L) was studied. Experiments were carried out using tubular microcosms operated in a greenhouse under plug flow conditions. Cr(VI) reduction was enhanced significantly by the presence of plants. This is explained by a decrease of the redox potential promoted by the root exudates released by the roots of the plants. Using these root exudates as their carbon source, and in the absence of nitrates, sulfate-reducing bacteria are able to reduce sulfate, building up the concentration of acid volatile sulfide (AVS), which in turn reduce Cr(VI) to Cr(III). Moreover, evapotranspiration induced by plants also contributes to enhance the removal of Cr(VI) by concentrating the species in the sediment porewater and therefore affecting the reaction kinetics. The effect of diurnal cycles on the Cr(VI) reduction rate has also been also studied. The diurnal cycle influences both root exudates released by plants as well as evapotranspiration. Higher levels of dissolved organic carbon in the pore water and evapotranspiration, occurring from around noon to 3 pm, correspond to a higher sulphate reduction rate and a lower redox potential in the sediments. This promotes a higher Cr(VI) removal during the day hours. Finally the Cr(VI) reduction dynamics were fitted to a kinetic equation that depends on the AVS and Cr(VI) concentration.

  8. Physiological changes in barley plants under combined toxicity of aluminum, copper and cadmium.

    PubMed

    Guo, Tian Rong; Zhang, Guo Ping; Zhang, Yan Hua

    2007-06-15

    Crop production on acid soil is markedly reduced, further, a multiple heavy metal pollution except Al on acid soil is detected in many areas. The present study was undertaken to assess the toxicities of Al, Cd, and Cu separately and in combinations, three heavy metals very often coexisting on acid soil, and to identify their interactions in two kinds of barley seedlings differing in Al tolerance. The plant growth, metals accumulations, total soluble protein and sugar contents, MDA contents and the activities of SOD and POD were estimated in roots and leaves after 5-week supply of the heavy metals excess in the nutrient solution. The results indicated that the stress treatments including low pH (pH 4.5) alone all adversely affected plant growth and disturbed the cell metabolism seriously. The development of toxic symptoms corresponded to a high accumulation of Al, Cd, Cu and to a poor increase in soluble sugar contents but to a high increase in MDA contents, to the decrease in soluble protein contents and to the much elevated SOD and POD activities in both roots and leaves. In addition, binary metal combinations of Al+Cd and Al+Cu both produced the synergistic response for the growth of barley seedlings, in particular for Shang 70-119, while, ternary metal combination of Al+Cu+Cd produced different interactions in two kinds of genotypes, thus, the significant synergistic response was seen in Shang 70-119, but the antagonistic response was detected in Gebeina. The different responses to ternary metal combination of two genotypes may result from the different metal bioaccumulation patterns, hence, the existence of Cd and Cu promoted Al accumulation in Shang 70-119 but inhibited Al accumulation in Gebeina.

  9. Plant functions in wetland and aquatic systems: influence of intensity and capacity of soil reduction.

    PubMed

    DeLaune, R D; Pezeshki, S R

    2001-11-07

    Wetland or hydric soils, in addition to excess water and limited air-filled porosity, are characterized by anaerobic or reducing conditions. Wetland plants have developed physiological and morphological adaptations for growing under these conditions. Various methods exist for measuring plant responses to reducing conditions in wetland and aquatic environments, including assessment of radial oxygen transport, cellular enzymatic transformations, changes in root structure, and nutrient uptake. However, a gap exists in quantifying the chemical properties and reducing nature of soil environment in which plant roots are grown. The variation in reducing conditions, oxygen demand, and other associated processes that occur in wetland soils makes it difficult to truly compare the plant responses reported in the literature. This review emphasizes soil-plant interactions in wetlands, drawing attention to the importance of quantifying the intensity and capacity of reduction and/or oxygen demand in wetland soils to allow proper evaluation of wetland plant responses to such conditions.

  10. Neuroprotective effects of Bacopa monniera whole-plant extract against aluminum-induced hippocampus damage in rats: evidence from electron microscopic images.

    PubMed

    Nannepaga, John Sushma; Korivi, Mallikarjuna; Tirumanyam, Madhavi; Bommavaram, Mahitha; Kuo, Chia-Hua

    2014-10-31

    Impaired antioxidant system and structural changes in hippocampus are considered as key instigators of neurodegenerative diseases. The present study aimed to investigate the antioxidant and tissue protective properties of Bacopa monniera whole-plant extract (BME) against aluminum (Al)- induced oxidative stress and hippocampus damage in rats. Male Wistar rats were evenly divided into four groups, nine in each and labeled as control, Al treated (10 mg/kg), BME administered (40 mg/kg) and combination of both Al plus BME (Al+BME) treated groups. After one month of treatment by oral administration, antioxidant status was determined, and structural changes in the hippocampus were evaluated by electron microscopy. Al-induced increased oxidative damage in the hippocampus was revealed by elevated thiobarbituric acid reactive substances (TBARS). This increased lipid peroxidation was associated with significantly decreased antioxidant enzyme activities, such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx). However, aluminum intoxicated rats treated with BME for 30 days showed significantly restored antioxidant enzyme activities along with decreased TBARS (P < 0.01). Further evidences from electron micrographs clearly indicated that Al-induced vacuolation, lipofuscin deposition and pyramidal cell degeneration in the hippocampus was attenuated with co-administration of the whole-plant extract. Our results demonstrate that structural derangement in hippocampus by aluminum is directly proportionate with increased lipid peroxidation. Nevertheless, B. monniera treatment potentiates the antioxidant status and suppressed the tissue damage induced by Al-intoxication. These findings suggest that B. monniera whole-plant extracts can be considered as a possible remedy to counteract aluminum-associated neurological disorders.

  11. [Cognitive disorders among welders exposed to aluminum].

    PubMed

    Giorgianni, C; Faranda, M; Brecciaroli, R; Beninato, G; Saffioti, G; Muraca, G; Congia, P; Catanoso, R; Agostani, G; Abbate, C

    2003-01-01

    In order to evaluate the relationship between exposure to aluminum and cognitive functions, a group of 50 aluminum welders underwent to the following neuropsychological tests: Wechsler Memory Scale, Color-Word Test and Raven Progressives Matrices test. The results of the tests showed a reduction of memory, of concentration and a slight reduction of attention. The authors conclude that aluminum exposure leads cognitive changes.

  12. Reduction of chlorinated solvents at the Y-12 Oak Ridge Plant

    SciTech Connect

    Thompson, L.M.; Simandl, R.F.; Richards, H.L.

    1989-11-01

    The Oak Ridge Y-12 Plant has been actively seeking replacements for chlorinated solvents for several years. The first step in the reduction program was the identification of the solvents and their usages. The four main solvents used at the plant include Freon, methyl chloroform, perchloroethylene, and methylene chloride. The main reduction has been in the use of perchloroethylene. Other significant reductions have occurred in the area of changing out vapor degreasers which utilized perchloroethylene or methyl chloroform. These degreasers were replaced with ultrasonic cleaners which utilize aqueous detergent for cleaning. Ultrasonic cleaning has many advantages, but the one disadvantage is that it requires a rinse step. Currently, the work on reduction of chlorinate solvents is focused on finding solvents which can be substituted for squirt bottle type applications. Concerns which were addressed when looking at replacement solvents were disposal, compatibility, and health effects.

  13. Primary water chemistry improvement for radiation exposure reduction at Japanese PWR Plants

    SciTech Connect

    Nishizawa, Eiichi

    1995-03-01

    Radiation exposure during the refueling outages at Japanese Pressurized Water Reactor (PWR) Plants has been gradually decreased through continuous efforts keeping the radiation dose rates at relatively low level. The improvement of primary water chemistry in respect to reduction of the radiation sources appears as one of the most important contributions to the achieved results and can be classified by the plant operation conditions as follows

  14. VS-501: a novel, nonabsorbed, calcium- and aluminum-free, highly effective phosphate binder derived from natural plant polymer

    PubMed Central

    Wu-Wong, J Ruth; Chen, Yung-wu; Gaffin, Robert; Hall, Andy; Wong, Jonathan T; Xiong, Joseph; Wessale, Jerry L

    2014-01-01

    Inadequate control of serum phosphate in chronic kidney disease can lead to pathologies of clinical importance. Effectiveness of on-market phosphate binders is limited by safety concerns and low compliance due to high pill size/burden and gastrointestinal (GI) discomfort. VS-501 is a nonabsorbed, calcium- and aluminum-free, chemically modified, plant-derived polymer. In vitro studies show that VS-501 has a high density and a low swell volume when exposed to simulated gastric fluid (vs. sevelamer). When male Sprague–Dawley (SD) rats on normal diet were treated with VS-501 or sevelamer, serum phosphate was not significantly altered, but urinary phosphate levels decreased by >90%. VS-501 had no effect on serum calcium (Ca) or urinary Ca, while 3% sevelamer significantly increased serum and urine Ca. In 5/6 nephrectomized (NX) uremic SD rats on high-phosphate diet, increasing dietary phosphate led to an increase in serum and urine phosphate, which was prevented in rats treated with VS-501 or sevelamer (0.2–5% in food). High-phosphate diet also increased serum fibroblast growth factor-23 and parathyroid hormone in 5/6 NX rats that was prevented by VS-501 or sevelamer. VS-501 or sevelamer increased fecal phosphate in a dose-dependent manner. More aortic calcification was observed in 5/6 NX rats treated with 5% sevelamer, while VS-501 and sevelamer did not show significant effects on cardiac parameters, fibrosis, intestine histology, and intestinal sodium-dependent phosphate cotransporter gene expression. These results suggest that VS-501 is effective in binding phosphate with no effects on calcium homeostasis, and may have improved pill burden and GI side effects. PMID:25197556

  15. WASTE REDUCTION PRACTICES AT TWO CHROMATED COPPER ARSENATE WOOD-TREATING PLANTS

    EPA Science Inventory

    Two chromated copper arsenate (CCA) wood-treating plants were assessed for their waste reduction practices. The objectives of this study were to estimate the amount of hazardous wastes that a well-designed and well-main- tained CCA treatment facility would generate and to iden- t...

  16. WASTE REDUCTION PRACTICES AT TWO CHROMATED COPPER ARSENATE WOOD-TREATING PLANTS

    EPA Science Inventory

    Two chromated copper arsenate (CCA) wood-treating plants were assessed for their waste reduction practices. The objectives of this study were to estimate the amount of hazardous wastes that a well-designed and well-main- tained CCA treatment facility would generate and to iden- t...

  17. Reduction of AOX in the bleach plant of a pulp mill.

    PubMed

    Barroca MJM; Seco, I M; Fernandes, P M; Ferreira, L M; Castro, J A

    2001-11-01

    The reconfiguration of an existing five-stage bleaching D0E1D1E2D2 sequence is proposed to ensure the minimal formation of organochlorine compounds, expressed as AOX, in the bleach plant of a kraft pulp mill processing Eucalyptus globulus wood. This reduction of the load of AOX in the effluents can be achieved without introducing new and expensive technologies in the bleaching process. In practice, this goal can be achieved by eliminating the washing step between the D0 and the E1 stages. With this strategy, the total AOX in the liquid effluent of the bleach plant can be reduced by almost 65% while maintaining a level of 90% ISO brightness of the pulp and even diminishing the degradation of its polysaccharides. With this process redesign, the total AOX discharge from the bleach plant can be decreased from 1.2 to 0.42 kg/t prior to any biological treatment. Furthermore, the proposed modified (D0E1)D1E2D2 sequence enables the reduction of the total flow rate of effluent to be treated and also the total consumption of water, which is quite critical in these types of plants. Moreover, with this strategy, one is able to move the first drum washer of a conventional bleaching sequence to the entrance of the bleach plant. This gives rise to a cleaner pulp and therefore to lower requirements of chlorine dioxide, which in turn will enable further reductions in the global AOX generation.

  18. Aluminum Hydroxide

    MedlinePlus

    Aluminum hydroxide is used for the relief of heartburn, sour stomach, and peptic ulcer pain and to ... Aluminum hydroxide comes as a capsule, a tablet, and an oral liquid and suspension. The dose and ...

  19. Wettable Ceramic-Based Drained Cathode Technology for Aluminum Electrolysis

    SciTech Connect

    J.N. Bruggeman; T.R. Alcorn; R. Jeltsch; T. Mroz

    2003-01-09

    The goal of the project was to develop the ceramic based materials, technology, and necessary engineering packages to retrofit existing aluminum reduction cells in order to reduce energy consumption required for making primary aluminum. The ceramic materials would be used in a drained cathode configuration which would provide a stable, molten aluminum wetted cathode surface, allowing the reduction of the anode-cathode distance, thereby reducing the energy consumption. This multi-tasked project was divided into three major tasks: (1) Manufacturing and laboratory scale testing/evaluation of the ceramic materials, (2) Pilot scale testing of qualified compositions from the first task, and (3) Designing, retrofitting, and testing the ceramic materials in industrial cells at Kaiser Mead plant in Spokane, Washington. Specific description of these major tasks can be found in Appendix A - Project Scope. Due to the power situation in the northwest, the Mead facility was closed, thus preventing the industrial cell testing.

  20. Water requirements of the aluminum industry

    USGS Publications Warehouse

    Conklin, Howard L.

    1956-01-01

    Aluminum is unique among metals in the way it is obtained from its ore. The first step is to produce alumina, a white powder that bears no resemblance to the bauxite from which it is derived or to the metallic aluminum to which it is reduced by electrolytic action in a second step. Each step requires a complete plant facility, and the plants may be adjacent or separated by as much as the width of the North American continent. Field investigations sf every alumina plant and reduction works in the United States were undertaken to determine the industry's water use. Detailed studies were made of process and plant layout so that a water balance could be made for each plant to determine not only the gross water intake but also an approximation of the consumptive use of water. Water requirements of alumina plants range from 0.28 to 1.10 gallons per pound of alumina; the average for the industry is 0.66 gallon. Water requirements of reduction works vary considerably more, ranging from 1.24 to 36.33 gallons per pound of aluminum, and average 14.62 gallons. All alumina plants in the United States derive alumina from bauxite by the Bayer process or by the Combination process, a modification of the Bayer process. Although the chemical process for obtaining alumina from bauxite is essentially the same at all plants, different procedures are employed to cool the sodium aluminate solution before it enters the precipitating tanks and to concentrate it by evaporation of some of the water in the solution. Where this evaporation takes place in a cooling tower, water in the solution is lost to the atmosphere as water vapor and so is used consumptively. In other plants, the quantity of solution in the system is controlled by evaporation in a multiple-effect evaporator where practically all vapor distilled out of the solution is condensed to water that may be reused. The latter method is used in all recently constructed alumina plants, and some older plants are replacing cooling towers

  1. Interaction between photorespiration and respiration in transgenic potato plants with antisense reduction in glycine decarboxylase.

    PubMed

    Bykova, Natalia V; Keerberg, Olav; Pärnik, Tiit; Bauwe, Hermann; Gardeström, Per

    2005-09-01

    Potato (Solanum tuberosum L. cv. Désirée) plants with an antisense reduction in the P-protein of the glycine decarboxylase complex (GDC) were used to study the interaction between respiration and photorespiration. Mitochondria isolated from transgenic plants had a decreased capacity for glycine oxidation and glycine accumulated in the leaves. Malate consumption increased in leaves of GDC deficient plants and the capacity for malate and NADH oxidation increased in isolated mitochondria. A lower level of alternative oxidase protein and decreased partitioning of electrons to the alternative pathway was found in these plants. The adenylate status was altered in protoplasts from transgenic plants, most notably the chloroplastic ATP/ADP ratio increased. The lower capacity for photorespiration in leaves of GDC deficient plants was compensated for by increased respiratory decarboxylations in the light. This is interpreted as a decreased light suppression of the tricarboxylic acid cycle in GDC deficient plants in comparison to wild-type plants. The results support the view that respiratory decarboxylations in the light are restricted at the level of the pyruvate dehydrogenase complex and/or isocitrate dehydrogenase and that this effect is likely to be mediated by mitochondrial photorespiratory products.

  2. Energy Saving Melting and Revert Reduction Technology (E-SMARRT): Development of Surface Engineered Coating Systems for Aluminum Pressure Die Casting Dies: Towards a 'Smart' Die Coating

    SciTech Connect

    Dr. John J. Moore; Dr. Jianliang Lin,

    2012-07-31

    The main objective of this research program was to design and develop an optimal coating system that extends die life by minimizing premature die failure. In high-pressure aluminum die-casting, the die, core pins and inserts must withstand severe processing conditions. Many of the dies and tools in the industry are being coated to improve wear-resistance and decrease down-time for maintenance. However, thermal fatigue in metal itself can still be a major problem, especially since it often leads to catastrophic failure (i.e. die breakage) as opposed to a wear-based failure (parts begin to go out of tolerance). Tooling costs remain the largest portion of production costs for many of these parts, so the ability prevent catastrophic failures would be transformative for the manufacturing industry.The technology offers energy savings through reduced energy use in the die casting process from several factors, including increased life of the tools and dies, reuse of the dies and die components, reduction/elimination of lubricants, and reduced machine down time, and reduction of Al solder sticking on the die. The use of the optimized die coating system will also reduce environmental wastes and scrap parts. Current (2012) annual energy saving estimates, based on initial dissemination to the casting industry in 2010 and market penetration of 80% by 2020, is 3.1 trillion BTU's/year. The average annual estimate of CO2 reduction per year through 2020 is 0.63 Million Metric Tons of Carbon Equivalent (MM TCE).

  3. Oxidation-reduction processes upon interaction of aluminum oxide melt with molybdenum and tungsten in a hydrogen-containing atmosphere

    NASA Astrophysics Data System (ADS)

    Kostomarov, D. V.

    2017-07-01

    A thermodynamic analysis of the processes occurring in the Mo-W-Al2O3 system at T = 2400 K and a total pressure of 1 bar, set by controlled reducing Ar + H2 atmosphere, has been performed. It is found that the basic components of the system do not interact directly, although may be actively involved in chemical reactions with participation of other components to undergo numerous cyclic oxidation-reduction processes. Particular attention is paid to the processes involving such chemically active reagents as H2O2, HO2, H2 (H), gaseous Al, and its hydrides (AlH, AlH2, AlH3).

  4. Plant sterols as dietary adjuvants in the reduction of cardiovascular risk: theory and evidence.

    PubMed

    Patch, Craig S; Tapsell, Linda C; Williams, Peter G; Gordon, Michelle

    2006-01-01

    Plant sterol-enriched foods are an effective dietary adjuvant in reducing cardiovascular risk by lowering total cholesterol and low density lipoprotein-cholesterol (LDL-C) in serum by up to approximately 15%. The mechanism of action of plant sterols is different from those of 3-hydroxy-3-methylglutaryl coenzyme A inhibitors (statins) and thus their effect is additive. Combining plant sterols with other dietary components known to reduce cholesterol in a portfolio approach has proven to be most effective for reduction of hypercholesterolemia and provide an alternative treatment option for clinicians. Plant sterol-enriched foods provides clinicians with a relatively cheap, safe, and effective way to help patients manage their cardiovascular risk.

  5. Potential of ozone utilization for reduction of pesticide residue in food of plant origin. A review.

    PubMed

    Balawejder, Maciej; Antos, Piotr; Sadło, Stanisław

    2013-01-01

    Residues of plant protection products can be nowadays found in almost all samples of fruits as even if their application was carried out with respect to standards of Good Agricultural Practice. The intake of these compounds with food of plant origin may result in various disorders and diseases. Since the use of plant protection agents seems unavoidable, it is necessary to treat contaminated food material to eliminate or reduce residues content within food products. Ozone is utilized for elimination of biological and chemical contaminants in various environmental matrixes. Since its utilization in food industry has been permitted many experiments were conducted in order to determine its efficiency and side effects on food quality. The goal of this paper is to contribute to a discussion on the ozonization as a process leading to reduction of pesticide residues on plant surface.

  6. Plant Sterols as Dietary Adjuvants in the Reduction of Cardiovascular Risk: Theory and Evidence

    PubMed Central

    Patch, Craig S; Tapsell, Linda C; Williams, Peter G; Gordon, Michelle

    2006-01-01

    Plant sterol-enriched foods are an effective dietary adjuvant in reducing cardiovascular risk by lowering total cholesterol and low density lipoprotein-cholesterol (LDL-C) in serum by up to ∼15%. The mechanism of action of plant sterols is different from those of 3-hydroxy-3-methylglutaryl coenzyme A inhibitors (statins) and thus their effect is additive. Combining plant sterols with other dietary components known to reduce cholesterol in a portfolio approach has proven to be most effective for reduction of hypercholesterolemia and provide an alternative treatment option for clinicians. Plant sterol-enriched foods provides clinicians with a relatively cheap, safe, and effective way to help patients manage their cardiovascular risk. PMID:17319460

  7. POTENTIAL HEALTH RISK REDUCTION ARISING FROM REDUCED MERCURY EMISSIONS FROM COAL FIRED POWER PLANTS.

    SciTech Connect

    Sullivan, T. M.; Lipfert, F. W.; Morris, S. C.; Moskowitz, P. D.

    2001-09-01

    The U.S. Environmental Protection Agency (EPA) has announced plans to regulate mercury (Hg) emissions from coal-fired power plants. EPA has not prepared a quantitative assessment of the reduction in risk that could be achieved through reduction in coal plant emissions of Hg. To address this issue, Brookhaven National Laboratory (BNL) with support from the U.S. Department of Energy Office of Fossil Energy (DOE FE) prepared a quantitative assessment of the reduction in human health risk that could be achieved through reduction in coal plant emissions of Hg. The primary pathway for Hg exposure is through consumption of fish. The most susceptible population to Hg exposure is the fetus. Therefore the risk assessment focused on consumption of fish by women of child-bearing age. Dose response factors were generated from studies on loss of cognitive abilities (language skills, motor skills, etc.) by young children whose mothers consumed large amounts of fish with high Hg levels. Population risks were estimated for the general population in three regions of the country, (the Midwest, Northeast, and Southeast) that were identified by EPA as being heavily impacted by coal emissions. Three scenarios for reducing Hg emissions from coal plants were considered: (1) A base case using current conditions; (2) A 50% reduction; and, (3) A 90% reduction. These reductions in emissions were assumed to translate linearly into a reduction in fish Hg levels of 8.6% and 15.5%, respectively. Population risk estimates were also calculated for two subsistence fisher populations. These groups of people consume substantially more fish than the general public and, depending on location, the fish may contain higher Hg levels than average. Risk estimates for these groups were calculated for the three Hg levels used for the general population analyses. Analysis shows that the general population risks for exposure of the fetus to Hg are small. Estimated risks under current conditions (i.e., no

  8. Serum Cholesterol Reduction Efficacy of Biscuits with Added Plant Stanol Ester

    PubMed Central

    Kriengsinyos, Wantanee; Wangtong, Ajima; Komindr, Surat

    2015-01-01

    This study's aim was to test the low-density lipoprotein cholesterol- (LDL-c-) lowering efficacy of biscuits containing 2 g of plant stanols, which corresponded to 3.4 g of plant stanol esters. The biscuit is a new food format that can be consumed as a snack. In a double-blind, placebo-controlled parallel design study, 119 mildly to moderately hypercholesterolemic volunteers were randomized to plant stanol or control groups. Subjects were comparable in age, gender, lipid profiles, and body mass index. They consumed a control biscuit once a day for a two-week period, followed by a four-week intervention period that either had a plant stanol ester biscuit or a control. During the habitual diet, one biscuit per day was consumed at any time that subjects wished. Serum lipid profiles were measured at the first day of run-in, at baseline, and at the study's end. Compared to the control, the total cholesterol (TC), LDL-c, and the LDL-to-high-density lipoprotein (LDL/HDL) ratio had serum reductions of 4.9%, 6.1%, and 4.3%, respectively, and were observed after 4 weeks of biscuit consumption with added plant stanols (P < 0.05). A significantly higher reduction in LDL-c (8.9%) and LDL/HDL ratio (11.4%) was measured in those taking a plant stanol biscuit with a meal compared to those who consumed a plant stanol biscuit without other food. In conclusion, incorporating plant stanols into a biscuit is an attractive, convenient, and acceptable way to modestly lower elevated cholesterol concentrations. For optimal efficacy, biscuits should be consumed with a meal as part of a healthy diet. PMID:25861469

  9. Aluminum: Reducing chloride emissions from aluminum production

    SciTech Connect

    Simon, P.

    1999-09-29

    Reynolds Metals Company (RMC), with assistance from a NICE{sup 3} grant, is developing for commercialization a closed-loop control process that greatly reduces chlorine emissions and increases plant efficiency while maintaining metal quality. The process still utilizes chlorine to remove impurities during aluminum processing, but is more effective than current methods. With the new technology chlorine in the stack is monitored and input chlorine is adjusted continuously. This optimization of chlorine use results in substantially less waste because less chlorine has to be bought or produced by aluminum manufacturers. This innovation is a significant improvement over conventional aluminum treatments, in which chlorine is injected in a more costly and wasteful manner. By the year 2010, the new technology has the potential to reduce the energy it takes to create chlorine by 8.4 billion Btu per year and to cut greenhouse gas emissions by 1,377 tons per year.

  10. Indirect carbon reduction by residential vegetation and planting strategies in Chicago, USA.

    PubMed

    Jo, H K; McPherson, E G

    2001-02-01

    Concern about climate change has evoked interest in the potential for urban vegetation to help reduce the levels of atmospheric carbon. This study applied computer simulations to try to quantify the modifying effects of existing vegetation on the indirect reduction of atmospheric carbon for two residential neighborhoods in north-west Chicago. The effects of shading, evapotranspiration, and windspeed reduction were considered and were found to have decreased carbon emissions by 3.2 to 3.9% per year for building types in study block 1 where tree cover was 33%, and -0.2 to 3.8% in block 2 where tree cover was 11%. This resulted in a total annual reduction of carbon emission averaging 158.7 (+/- 12.8) kg per residence in block 1 and 18.1 (+/- 5.4) kg per residence in block 2. Windspeed reduction greatly contributed to the decrease of carbon emission. However, shading increased annual carbon emission from the combined change in heating and cooling energy use due to many trees in the wrong locations, which increase heating energy use during the winter. The increase of carbon emission from shading is somewhat specific to Chicago, due in part to the large amount of clean, nuclear-generated cooling energy and the long heating season. In Chicago, heating energy is required for about eight months from October to May and cooling energy is used for the remaining 4 months from June to September. If fossil fuels had been the primary source for cooling energy and the heating season had been shorter, the shading effects on the reduction of carbon emission would be greater. Planting of large trees close to the west wall of buildings, dense planting on the north, and avoidance of planting on the south are recommended to maximize indirect carbon reduction by residential vegetation, in Chicago and other mid and high-latitude cities with long heating seasons.

  11. Uptake and Reduction of [15N]Nitrate by Intact Soybean Plants in the Dark

    PubMed Central

    Nicholas, Joseph C.; Harper, James E.

    1985-01-01

    Experiments were conducted to determine if nitrate (15N-labeled) was taken up and assimilated by intact soybean (Glycine max [L.] Merr. cv Williams) plants during extended periods of dark. Nitrate was taken up by soybean roots throughout a 12-hour dark period. The 15N-labeled nitrogen was also translocated to the plant shoots, but at a slower rate than the rate of accumulation in the roots. Much of the nitrogen (15N-labeled) was present in a nonreduced form, although considerable soluble-reduced nitrogen (15N-labeled) accumulated throughout the dark period. The 15N-labeled, soluble-reduced nitrogen fraction accounted for nearly 30% of the total 15N found in plant roots and more than 63% of the total 15N found in plant tops after 12 hours of dark. This provided evidence that intact soybean plants take up and metabolize significant quantities of nitrate to reduced N forms in the dark. In addition to nitrate influx during the dark, it was shown that there was a concomitant loss of 15N-labeled nitrogen compounds from previously 15N-labeled plants to a natural abundance 15N nutrient solution. Thus, evidence was obtained which indicated that light was not directly essential for flux and reduction of nitrate by intact soybean plants. PMID:16664059

  12. Oxidation-reduction processes in ground water at Naval Weapons Industrial Reserve Plant, Dallas, Texas

    USGS Publications Warehouse

    Jones, S.A.; Braun, Christopher L.; Lee, Roger W.

    2003-01-01

    Concentrations of trichloroethene in ground water at the Naval Weapons Industrial Reserve Plant in Dallas, Texas, indicate three source areas of chlorinated solvents?building 1, building 6, and an off-site source west of the facility. The presence of daughter products of reductive dechlorination of trichloroethene, which were not used at the facility, south and southwest of the source areas are evidence that reductive dechlorination is occurring. In places south of the source areas, dissolved oxygen concentrations indicated that reduction of oxygen could be the dominant process, particularly south of building 6; but elevated dissolved oxygen concentrations south of building 6 might be caused by a leaking water or sewer pipe. The nitrite data indicate that denitrification is occurring in places; however, dissolved hydrogen concentrations indicate that iron reduction is the dominant process south of building 6. The distributions of ferrous iron indicate that iron reduction is occurring in places south-southwest of buildings 6 and 1; dissolved hydrogen concentrations generally support the interpretation that iron reduction is the dominant process in those places. The generally low concentrations of sulfide indicate that sulfate reduction is not a key process in most sampled areas, an interpretation that is supported by dissolved hydrogen concentrations. Ferrous iron and dissolved hydrogen concentrations indicate that ferric iron reduction is the primary oxidation-reduction process. Application of mean first-order decay rates in iron-reducing conditions for trichloroethene, dichloroethene, and vinyl chloride yielded half-lives for those solvents of 231, 347, and 2.67 days, respectively. Decay rates, and thus half-lives, at the facility are expected to be similar to those computed. A weighted scoring method to indicate sites where reductive dechlorination might be likely to occur indicated strong evidence for anaerobic biodegradation of chlorinated solvents at six sites

  13. Waste reduction assistance program (WRAP) on-site consultation audit report: Seafood processing plant

    SciTech Connect

    Not Available

    1989-07-29

    The waste audit study was conducted at a seafood processing plant in Alaska. The report discusses process descriptions, waste types and quantities, current waste and materials management practices, and waste reduction alternatives. The company's current practices include use of fish waste, burning of used oil and solvents, and water conservation. Additional opportunities include microfiltration of solvents and oils, recycling of used batteries, inventory control and formation of a waste reduction team. Appendices include a summary of state regulations, a fact sheet on used oil, and a list of vendors and services.

  14. Reduction of interpore distance of anodized aluminum oxide nano pattern by mixed H3PO4:H2SO4 electrolyte.

    PubMed

    Song, Kwang Min; Park, Joonmo; Ryu, Sang-Wan

    2007-11-01

    A self-formed and ordered anodized aluminum oxide (AAO) nano pattern has generated considerable interest in both scientific research and commercial application. However, the interpore distance obtainable by AAO is limited by 40-500 nm depending on electrolyte and anodizing voltage. It's believed that below-30 nm AAO pattern is a key technology in the fabrication semiconductor nano structures with enhanced quantum confinement effect, so we worked on the reduction of interpore distance of AAO with a novel electrolyte. AAO nano patterns were fabricated with mixed H2SO4 and H3PO4 as an electrolyte for various voltages and temperatures. The interpore distance and pore diameter of AAO were decreased with reduced anodizing voltage. As a result, an AAO nano pattern with the interpore distance of 27 nm and the pore diameter of 7 nm was obtained. This is the smallest pattern, as long as we know, reported till now with AAO technique. The fabricated AAO pattern could be utilized for uniform and high density quantum dots with increased quantum effect.

  15. Observations and Modeling of US Power Plant NOx Emission Reductions and Their Impact on Air Quality

    NASA Astrophysics Data System (ADS)

    Frost, G. J.; Kim, S.; McKeen, S.; Hsie, E.; Trainer, M.; Heckel, A.; Richter, A.; Burrows, J.

    2007-12-01

    Nitrogen oxide (NOx) emissions resulting from fossil fuel combustion lead to unhealthy levels of near-surface ozone (O3). One of the largest US sources, electric power generation, represented about 25% of US anthropogenic NOx emissions prior to the recent implementation of pollution controls by utility companies. Continuous emission monitoring data demonstrate that overall US power plant NOx emissions decreased about 50% during the summer ozone season since the late 1990's. Space-based instruments observed declining regional NOx levels between 1999 and 2005 in response to these emission reductions. Satellite-retrieved summertime nitrogen dioxide (NO2) columns and bottom-up emission estimates show larger decreases in the Ohio River Valley, where power plants dominate NOx emissions, than in the northeast US urban corridor. Model simulations predict lower O3 across much of the eastern US in response to these emission reductions.

  16. Geothermal Risk Reduction via Geothermal/Solar Hybrid Power Plants. Final Report

    SciTech Connect

    Wendt, Daniel; Mines, Greg; Turchi, Craig; Zhu, Guangdong

    2015-11-01

    are subject to decreasing productivity manifested in the form of decreasing production fluid temperature, flow rate, or both during the life span of the associated power generation project. The impacts of geothermal production fluid temperature decline on power plant performance can be significant; a reduction in heat input to a power plant not only decreases the thermal energy available for conversion to electrical power, but also adversely impacts the power plant efficiency. The impact of resource productivity decline on power generation project economics can be equally detrimental. The reduction in power generation is directly correlated to a reduction in revenues from power sales. Further, projects with Power Purchase Agreement (PPA) contracts in place may be subject to significant economic penalties if power generation falls below a specified default level. While the magnitude of PPA penalties varies on a case-by-case basis, it is not unrealistic for these penalties to be on the order of the value of the deficit power sales such that the utility may purchase the power elsewhere. This report evaluates the use of geothermal/solar-thermal hybrid plant technology for mitigation of resource productivity decline, which has not been a primary topic of investigation in previous analyses in the open literature.

  17. Effects of soil oxidation-reduction conditions on internal oxygen transport, root aeration, and growth of wetland plants

    Treesearch

    S.R. Pezeshki; R.D. DeLaune

    2000-01-01

    Characterization of hydric soils and the relationship between soil oxidation-reduction processes and wetland plant distribution are critical to the identification and delineation of wetlands and to our understanding of soil processes and plant functioning in wetland ecosystems. However, the information on the relationship between flood response of wetland plants and...

  18. Behavior of aluminum in aluminum welders and manufacturers of aluminum sulfate--impact on biological monitoring.

    PubMed

    Riihimäki, Vesa; Valkonen, Sinikka; Engström, Bernt; Tossavainen, Antti; Mutanen, Pertti; Aitio, Antero

    2008-12-01

    The suitability of determining aluminum in serum or urine as a form of biological monitoring was critically assessed. Airborne and internal aluminum exposure was assessed for 12 aluminum welders in a shipyard and 5 manufacturers of aluminum sulfate. Particles were characterized with X-ray diffraction and scanning electron microscopy. Aluminum in air and biological samples was analyzed using electrothermal atomic absorption spectrometry. Basic toxicokinetic features were inferred from the data. The mean 8-hour time-weighted average concentration of aluminum was 1.1 (range 0.008-6.1) mg/m(3) for the shipyard and 0.13 (range 0.02-0.5) mg/m(3) for the aluminum sulfate plant. Welding fume contained aluminum oxide particles <0.1 microm in diameter and their agglomerates, whereas bauxite and aluminum sulfate particles ranged from 1 to 10 microm in diameter. The shipyard welders' mean postshift serum and urinary concentrations of aluminum (S-Al and U-Al, respectively) were 0.22 and 3.4 micromol/l, respectively, and the aluminum sulfate workers' corresponding values were 0.13 and 0.58 micromol/l. Between two shifts, the welders' S-Al concentration decreased by about 50% (P<0.01), but their U-Al concentration did not change (P=0.64). No corresponding temporal changes occurred among the aluminum sulfate workers. After aluminum welding at the shipyard had ceased, the median S-Al concentration decreased by about 50% (P=0.007) within a year, but there was no change (P=0.75) in the corresponding U-Al concentration. About 1% of aluminum in welding fume appears to be rapidly absorbed from the lungs, whereas an undetermined fraction is retained and forms a lung burden. A higher fractional absorption of aluminum seems possible for aluminum sulfate workers without evidence of a lung burden. After rapid absorption, aluminum is slowly mobilized from the lung burden and dominates the S-Al and U-Al concentrations of aluminum welders. For kinetic reasons, S-Al or U-Al concentrations cannot

  19. Effects of dose limits reduction on the Argentine nuclear power plants

    SciTech Connect

    Palacios, E.; Curti, A.; Massera, G.; Spano, F.; Boutet, L. )

    1993-11-01

    Occupational doses are evaluated in different stages of the fuel cycle and in the operation of nuclear power plants. Trends in individual dose distribution and collective doses are analyzed. The most contributive working conditions to collective dose are identified and the implications of dose limit reduction recommended by the ICRP in 1990 are assessed. It is concluded that no relevant difficulties should appear in accomplishing the new recommendations except for implementation at Atucha I, a nuclear power plant designed in the 1960s. Some options to reduce individual and collective doses in this plant are analyzed. The change of fuel channels by new ones free from cobalt is essential to get effective improvement of occupational exposures.

  20. Reduction of divinyl ether-containing polyunsaturated fatty acids in transgenic potato plants.

    PubMed

    Eschen-Lippold, Lennart; Rothe, Grit; Stumpe, Michael; Göbel, Cornelia; Feussner, Ivo; Rosahl, Sabine

    2007-03-01

    Oxygenated polyunsaturated fatty acids synthesized via the lipoxygenase pathway play a role in plant responses to pathogen attack. In solanaceous plants, the preferential stimulation of the 9-lipoxygenase pathway in response to pathogen infection leads to the formation of the divinyl ether-containing polyunsaturated fatty acids colneleic and colnelenic acid, as well as hydroxy and trihydroxy polyunsaturated fatty acids. To functionally assess the role of divinyl ethers, transgenic potato plants were generated which express an RNA interference construct directed against the pathogen-inducible 9-divinyl ether synthase. Efficient reduction of 9-divinyl ether synthase transcript accumulation correlated with reduced levels of colneleic and colnelenic acid. However, in response to infection with virulent Phytophthora infestans, the causal agent of late blight disease, no significant differences in pathogen biomass could be detected suggesting that the levels of antimicrobial divinyl ethers are not critical for defense against Phytophthora infestans in a compatible interaction.

  1. Plant-order Reduction for I-PD Controller Design and Its Application to Flight Control

    NASA Astrophysics Data System (ADS)

    Kondo, Hiroyuki; Ochi, Yoshimasa

    This paper proposes an I-PD (integral preceded by proportional-derivative) controller design with a more rational method of plant-order reduction to the second order than the method previously proposed by the authors, where parameter-space search was employed. In the new method, first, the fractional balanced reduction is applied to the original single-input-single-output plant. Then, the reduced-order model is adjusted via the homotopy method in terms of the ν-gap metric. The method can also be applied to a plant that is not stable but stabilizable by state feedback in the same way. The resultant PID controller designed based on the optimal servomechanism using the second-order plant model provides preferable properties as a linear quadratic regulator (LQR), if the ν-gap can be made sufficiently small. Moreover, it can be extended to a model-following type by adding a reference model and a feedforward compensator to improve the output responses without decreasing the stability margins. The effectiveness and usefulness of the proposed method are demonstrated through design examples including an application to flight control and numerical simulations.

  2. Ion Exchange Media for Reduction of Liquid Radwaste in Commercial Power Plants

    SciTech Connect

    Yarnell, P.A.; Tavares, A.

    2008-07-01

    Ion exchange resins currently make up as much as one-half of all radioactive waste generated by commercial nuclear power plants. A major challenge is reduction of the quantity of ion exchange media requiring disposal. Although the amount of spent ion exchange resins disposed has decreased year after year, a new urgency has arisen with the pending closure of a major disposal site in 2008. This paper explores whether ion exchange resins also can be used to potentially reduce radioactive liquid waste volumes and / or limit them to Class A wastes only. Source term reduction and minimization of manpower exposure to radioactivity are other important goals. Specialty ion exchange products may help to achieve source term reduction of certain radionuclides. Some established operations, data, and process concepts are presented to address these critical issues encountered in liquid radwaste management. (authors)

  3. Limestone/adipic acid FGD and stack opacity reduction pilot plant tests at Big Rivers

    SciTech Connect

    Laslo, D.; Bakke, E.; Chisholm, E.

    1984-01-01

    Big Rivers Electric Corporation (BREC) contracted Peabody Process Systems, Inc. (PPSI) to install a flue gas cleaning (FGC) pilot plant at the BREC R.D. Green Station Unit No. 2 located at Sebree, KY. A six month test program was completed demonstrating technology for: alternatives to using lime as an alkali; methods for improving cake dewatering; identification of the causes of high stack opacity; and methods for the reduction of high stack opacity. This paper presents highlights extracted from the reports submitted by PPSI to BREC on this test program. BREC was primarily interested in reduction of operating costs, if possible, by using an alkali less expensive than lime, and by improving the poor dewatering characteristic inherent in a dolomitic lime system. BREC was also within compliance for particulate emissions and opacity in the duct after the dry electrostatic precipitator, but not in compliance with the stack opacity regulation, and therefore wanted to investigate methods for stack opacity reduction.

  4. Reducing aluminum: an occupation possibly associated with bladder cancer.

    PubMed Central

    Thériault, G; De Guire, L; Cordier, S

    1981-01-01

    A case-control study, undertaken to identify reasons for the exceptionally high incidence of bladder cancer among men in the Chicoutimi census division of the province of Quebec, revealed an increased risk associated with employment in the electrolysis department of an aluminum reduction plant. The estimated relative risk was 2.83 (95% confidence interval; 1.06 to 7.54). An interaction was found between such employment and cigarette smoking, resulting in a combined relative risk of 5.70 (95% confidence interval: 2.00 to 12.30). These findings suggest that employment in an aluminum reduction plant accounts for part of the excess of bladder cancer in the region studied. PMID:7214271

  5. Mechanisms of aluminum tolerance

    USDA-ARS?s Scientific Manuscript database

    Aluminum (Al) toxicity limits agricultural productivity over much of the world’s arable land by inhibiting root growth and development. Affected plants have difficulty in acquiring adequate water and nutrition from their soil environments and thus have stunted shoot development and diminished yield....

  6. Maize aluminum tolerance

    USDA-ARS?s Scientific Manuscript database

    Maize is one of the most economically important food crops grown on acid soils, where aluminum (Al) toxicity greatly limits crop yields. Considerable variation for Al tolerance exists in maize, and this variation has been exploited for many years by plant breeders to enhance maize Al tolerance. Curr...

  7. Building an aluminum car

    SciTech Connect

    Ashley, S.

    1994-05-01

    This article examines the increasing use of aluminum in automobiles to decrease weight and consequently increase fuel economy. The topics of the article include federal fuel economy goals, the development of optimum body structure and manufacturing techniques, comparison with steel, cost of materials, weight reduction and recycling of materials.

  8. Cost-benefit analysis of a plant sterol containing low-fat margarine for cholesterol reduction.

    PubMed

    Gerber, A; Evers, T; Haverkamp, H; Lauterbach, K W

    2006-12-01

    For decreasing the risk of coronary heart disease (CHD) it has been proposed to enrich food such as margarine with plant sterol esters which have been shown to reduce total and LDL cholesterol concentrations, two of the major risk factors. A Markov model was developed to assess the costs and benefits of consuming a low-fat plant sterol containing margarine (PS margarine). A health insurer's perspective was taken with a time frame of 10 years. Transition probabilities for CHD and CHD-related death were calculated on the basis of the Framingham risk equations. These were applied to a representative sample of the German population. The alteration in cholesterol levels after intake of PS margarine was estimated based on a meta-analysis of ten randomized controlled trials with parallel or crossover design that found a reduction of 5.7% in total cholesterol. Average annual costs of CHD were assumed to be at 3,000 euro. Costs for "no CHD" and "CHD-related death" were set to 0 euro since the intervention would solely be paid by the consumers. Sensitivity analyses were performed with regard to annual costs, risk estimation, PS margarine reduction in total cholesterol, discount factor, and risk of CHD-related death. The 10-year CHD risks are 6.1% (PS margarine) vs. 6.5% (control). Thus expected 10-year CHD costs are 696 euro (PS margarine) vs. 748 euro (control). The cost savings of 52 euro varied between 32 euro and 74 euro in the sensitivity analysis. A projection at the level of the population for which evidence (randomized controlled trials) exists that plant sterols lower cholesterol (25.35 million) leads to a reduction of 117,000 CHD cases over 10 years and a cost reduction of 1.3 billion euro for this time period (sensitivity analysis 0.8-1.9 billion euro).

  9. Toxicity reduction evaluation at the Patapsco Waste Water Treatment plant. Final report, April 1986-September 1987

    SciTech Connect

    Botts, J.A.; Braswell, J.W.; Sullivan, E.C.; Goodfellow, W.L.; Sklar, B.D.

    1988-06-01

    The EPA and the City of Baltimore (City) entered into a cooperative agreement to perform a TRE research study at the City's Patapsco Waste Water Treatment Plant (Patapsco WWTP). The Patapsco WWTP TRE represents one of the first case histories of a toxics management program at a municipal waste-water treatment plant. The study characterized treatment plant influent and operations data and related these data to waste-water toxicity and inhibition data; characterized the plant's influent and effluent waste-water toxicity using definitive EPA bioassays and in-plant toxicity monitors; evaluated the fate of toxicity and specific toxic chemicals during treatment; and evaluated techniques to trace toxicity to its source and to identify specific components of toxicity. A major reduction in toxicity was achieved by the Patapsco WWTP; substantial acute and chronic toxicity was present in the Patapsco WWTP effluent. The waste-water fractionation/identification procedures identified nonpolar organic compounds as the principal toxicants while compounds removed by volatilization and ammonia contributed lesser amounts of toxicity.

  10. Aluminum toxicity in tomato. Part 2.Leaf gas exchange, chlorophyll content, and invertase activity

    Treesearch

    L. Simon; M. Kieger; Shi-Jean S. Sung; T.J. Smalley

    1994-01-01

    The effect of aluminum (Al) toxicity on leaf gas exchange, leaf chlorophyll content, and sucrose metabolizing enzyme activity of two tomato cultivars (Lycopersicon esculentum Mill. 'Mountain Pride' and 'Floramerica') was studied to determine the mechanism of growth reduction observed in a related study (Simon et al., 1994, Part 1).Plants were grown...

  11. Energy-Saving Melting and Revert Reduction Technology (E-SMARRT): Development of Elevated Temperature Aluminum Metal Matrix Composite (MMC) Alloy and Its Processing Technology

    SciTech Connect

    Weiss, David C.; Gegal, Gerald A.

    2014-04-15

    The objective of this project was to provide a production capable cast aluminum metal matrix composite (MMC) alloy with an operating temperature capability of 250-300°C. Important industrial sectors as well as the military now seek lightweight aluminum alloy castings that can operate in temperature ranges of 250-300°C. Current needs in this temperature range are being satisfied by the use of titanium alloy castings. These have the desired strength properties but the end components are heavier and significantly more costly. Also, the energy requirements for production of titanium alloy castings are significantly higher than those required for production of aluminum alloys and aluminum alloy castings.

  12. Sludge reduction in a small wastewater treatment plant by electro-kinetic disintegration.

    PubMed

    Chiavola, Agostina; Ridolfi, Alessandra; D'Amato, Emilio; Bongirolami, Simona; Cima, Ennio; Sirini, Piero; Gavasci, Renato

    2015-01-01

    Sludge reduction in a wastewater treatment plant (WWTP) has recently become a key issue for the managing companies, due to the increasing constraints on the disposal alternatives. Therefore, all the solutions proposed with the aim of minimizing sludge production are receiving increasing attention and are tested either at laboratory or full-scale to evaluate their real effectiveness. In the present paper, electro-kinetic disintegration has been applied at full-scale in the recycle loop of the sludge drawn from the secondary settlement tank of a small WWTP for domestic sewage. After the disintegration stage, the treated sludge was returned to the biological reactor. Three different percentages (50, 75 and 100%) of the return sludge flow rate were subjected to disintegration and the effects on the sludge production and the WWTP operation efficiency evaluated. The long-term observations showed that the electro-kinetic disintegration was able to drastically reduce the amount of biological sludge produced by the plant, without affecting its treatment efficiency. The highest reduction was achieved when 100% return sludge flow rate was subjected to the disintegration process. The reduced sludge production gave rise to a considerable net cost saving for the company which manages the plant.

  13. Data base on dose reduction research projects for nuclear power plants. Volume 5

    SciTech Connect

    Khan, T.A.; Yu, C.K.; Roecklein, A.K.

    1994-05-01

    This is the fifth volume in a series of reports that provide information on dose reduction research and health physics technology or nuclear power plants. The information is taken from two of several databases maintained by Brookhaven National Laboratory`s ALARA Center for the Nuclear Regulatory Commission. The research section of the report covers dose reduction projects that are in the experimental or developmental phase. It includes topics such as steam generator degradation, decontamination, robotics, improvements in reactor materials, and inspection techniques. The section on health physics technology discusses dose reduction efforts that are in place or in the process of being implemented at nuclear power plants. A total of 105 new or updated projects are described. All project abstracts from this report are available to nuclear industry professionals with access to a fax machine through the ACEFAX system or a computer with a modem and the proper communications software through the ACE system. Detailed descriptions of how to access all the databases electronically are in the appendices of the report.

  14. Excess dietary aluminum increases Drosophila's rate of aging.

    PubMed

    Massie, H R; Williams, T R; Aiello, V R

    1985-01-01

    Aluminum concentrations in the whole organism increased during development and aging of Drosophila melanogaster. The amount of aluminum in the flies was also reflected by the dietary content of aluminum. Additional dietary aluminum, in the form of aluminum salts, decreased the life span by as much as 20%. A significant reduction in life span was found for 1 X 10(-4) M aluminum chloride and for 1 X 10(-3) M aluminum nitrate and aluminum sulfate. Dietary sodium fluoride failed to increase life span.

  15. Regeneration of aluminum hydride

    DOEpatents

    Graetz, Jason Allan; Reilly, James J.

    2009-04-21

    The present invention provides methods and materials for the formation of hydrogen storage alanes, AlH.sub.x, where x is greater than 0 and less than or equal to 6 at reduced H.sub.2 pressures and temperatures. The methods rely upon reduction of the change in free energy of the reaction between aluminum and molecular H.sub.2. The change in free energy is reduced by lowering the entropy change during the reaction by providing aluminum in a state of high entropy, by increasing the magnitude of the change in enthalpy of the reaction or combinations thereof.

  16. Regeneration of aluminum hydride

    DOEpatents

    Graetz, Jason Allan; Reilly, James J; Wegrzyn, James E

    2012-09-18

    The present invention provides methods and materials for the formation of hydrogen storage alanes, AlH.sub.x, where x is greater than 0 and less than or equal to 6 at reduced H.sub.2 pressures and temperatures. The methods rely upon reduction of the change in free energy of the reaction between aluminum and molecular H.sub.2. The change in free energy is reduced by lowering the entropy change during the reaction by providing aluminum in a state of high entropy, and by increasing the magnitude of the change in enthalpy of the reaction or combinations thereof.

  17. Ascorbate Efflux as a New Strategy for Iron Reduction and Transport in Plants*

    PubMed Central

    Grillet, Louis; Ouerdane, Laurent; Flis, Paulina; Hoang, Minh Thi Thanh; Isaure, Marie-Pierre; Lobinski, Ryszard; Curie, Catherine; Mari, Stéphane

    2014-01-01

    Iron (Fe) is essential for virtually all living organisms. The identification of the chemical forms of iron (the speciation) circulating in and between cells is crucial to further understand the mechanisms of iron delivery to its final targets. Here we analyzed how iron is transported to the seeds by the chemical identification of iron complexes that are delivered to embryos, followed by the biochemical characterization of the transport of these complexes by the embryo, using the pea (Pisum sativum) as a model species. We have found that iron circulates as ferric complexes with citrate and malate (Fe(III)3Cit2Mal2, Fe(III)3Cit3Mal1, Fe(III)Cit2). Because dicotyledonous plants only transport ferrous iron, we checked whether embryos were capable of reducing iron of these complexes. Indeed, embryos did express a constitutively high ferric reduction activity. Surprisingly, iron(III) reduction is not catalyzed by the expected membrane-bound ferric reductase. Instead, embryos efflux high amounts of ascorbate that chemically reduce iron(III) from citrate-malate complexes. In vitro transport experiments on isolated embryos using radiolabeled 55Fe demonstrated that this ascorbate-mediated reduction is an obligatory step for the uptake of iron(II). Moreover, the ascorbate efflux activity was also measured in Arabidopsis embryos, suggesting that this new iron transport system may be generic to dicotyledonous plants. Finally, in embryos of the ascorbate-deficient mutants vtc2-4, vtc5-1, and vtc5-2, the reducing activity and the iron concentration were reduced significantly. Taken together, our results identified a new iron transport mechanism in plants that could play a major role to control iron loading in seeds. PMID:24347170

  18. Ascorbate efflux as a new strategy for iron reduction and transport in plants.

    PubMed

    Grillet, Louis; Ouerdane, Laurent; Flis, Paulina; Hoang, Minh Thi Thanh; Isaure, Marie-Pierre; Lobinski, Ryszard; Curie, Catherine; Mari, Stéphane

    2014-01-31

    Iron (Fe) is essential for virtually all living organisms. The identification of the chemical forms of iron (the speciation) circulating in and between cells is crucial to further understand the mechanisms of iron delivery to its final targets. Here we analyzed how iron is transported to the seeds by the chemical identification of iron complexes that are delivered to embryos, followed by the biochemical characterization of the transport of these complexes by the embryo, using the pea (Pisum sativum) as a model species. We have found that iron circulates as ferric complexes with citrate and malate (Fe(III)3Cit2Mal2, Fe(III)3Cit3Mal1, Fe(III)Cit2). Because dicotyledonous plants only transport ferrous iron, we checked whether embryos were capable of reducing iron of these complexes. Indeed, embryos did express a constitutively high ferric reduction activity. Surprisingly, iron(III) reduction is not catalyzed by the expected membrane-bound ferric reductase. Instead, embryos efflux high amounts of ascorbate that chemically reduce iron(III) from citrate-malate complexes. In vitro transport experiments on isolated embryos using radiolabeled (55)Fe demonstrated that this ascorbate-mediated reduction is an obligatory step for the uptake of iron(II). Moreover, the ascorbate efflux activity was also measured in Arabidopsis embryos, suggesting that this new iron transport system may be generic to dicotyledonous plants. Finally, in embryos of the ascorbate-deficient mutants vtc2-4, vtc5-1, and vtc5-2, the reducing activity and the iron concentration were reduced significantly. Taken together, our results identified a new iron transport mechanism in plants that could play a major role to control iron loading in seeds.

  19. Hydrogen reduction in heat transfer fluid in parabolic trough CSP plants

    NASA Astrophysics Data System (ADS)

    Lang, Christoph; Belkheir, Mohamed; Kim, Eungkyu; Davidson, Chet; Holden, Bruce; Hook, Bruce

    2017-06-01

    Hydrogen (H2) has been found to be generated in very small proportions when diphenyl oxide/ biphenyl heat transfer fluid (HTF) is operated at temperatures close to 400°C. At such temperatures, H2 can permeate through steel walls to the vacuum space of parabolic trough (PT) solar receivers, where it increases heat losses that can significantly impact the economics of PT concentrated solar power plants. A novel process for the reduction of the H2 concentration in HTF via stripping and gas separation has been simulated for the operation in PT CSP plants. Applying the proposed process, the concentration of H2 in HTF can be reduced down to 1 ppb. A cost comparison between the H2 separation process and frequent PT receivers replacement was conducted and found that proposed H2 removal process is more economic.

  20. Detailed plans for the reduction in waste load from a dairy and ice cream plant

    SciTech Connect

    Carawan, R.E.; Rushing, J.E.

    1987-02-28

    The waste load from a dairy processing plant is largely a result of milk products which are intentionally or inadvertaintly lost to the sewer system. Researchers have estimated that over 90 percent of the waste load is of product origin (milk and milk products). The reduction of water and waste requires the application of the best technology to achieve reduced product loss, reduced water usage and reduced ingredient loss. There are two proven ways to reduce water use, wastewater discharge, waste loads and product loss. One method is to operate the plant more efficiently. The other is to institute process changes which have been shown to reduce water use, product waste and wasteloads. This project places emphasis on detailing those losses, recovering these losses, and preventing the milk solids from becoming part of the waste load.

  1. Dose reduction and cost-benefit analysis at Japan`s Tokai No. 2 Plant

    SciTech Connect

    Humamoto, Hisao; Suzuki, Seishiro; Taniguchi, Kazufumi

    1995-03-01

    In the Tokai No. 2 power plant of the Japan Atomic Power Company, about 80% of the annual dose equivalent is received during periodic maintenance outages. A project group for dose reduction was organized at the company`s headquarters in 1986; in 1988, they proposed a five-year program to reduce by half the collective dose of 4 person-Sv per normal outage work. To achieve the target dose value, some dose-reduction measures were undertaken, namely, permanent radiation shielding, decontamination, automatic, operating machines, and ALARA organization. As the result, the collective dose from normal outage work was 1.6 person-Sv in 1992, which was less than the initial target value.

  2. The use of primary dross from the aluminum industry for manufacturing aluminum sulfate

    SciTech Connect

    Osborne, B.W.

    1995-12-31

    The use of primary dross as a source for aluminum ion in the manufacture of aluminum sulfate offers opportunities for an inexpensive raw material. The aluminum sulfate industry in the US is a mature market with numerous small plants operating close to major users. The majority of manufacturers use either bauxite or aluminum oxide trihydrate as a source for the aluminum ion. However, using process technology developed and patented by IWC, the oxides are removed from primary dross for use in manufacturing aluminum sulfate prior to metal recovery. This process offers the benefit of reducing costs for metal recovery. This paper discusses some of the methodology used in this process.

  3. Role of Lipid Composition and Lipid Peroxidation in the Sensitivity of Fungal Plant Pathogens to Aluminum Chloride and Sodium Metabisulfite▿

    PubMed Central

    Avis, Tyler J.; Michaud, Mélanie; Tweddell, Russell J.

    2007-01-01

    Aluminum chloride and sodium metabisulfite have shown high efficacy at low doses in controlling postharvest pathogens on potato tubers. Direct effects of these two salts included the loss of cell membrane integrity in exposed pathogens. In this work, four fungal potato pathogens were studied in order to elucidate the role of membrane lipids and lipid peroxidation in the relative sensitivity of microorganisms exposed to these salts. Inhibition of mycelial growth in these fungi varied considerably and revealed sensitivity groups within the tested fungi. Analysis of fatty acids in these fungi demonstrated that sensitivity was related to high intrinsic fatty acid unsaturation. When exposed to the antifungal salts, sensitive fungi demonstrated a loss of fatty acid unsaturation, which was accompanied by an elevation in malondialdehyde content (a biochemical marker of lipid peroxidation). Our data suggest that aluminum chloride and sodium metabisulfite could induce lipid peroxidation in sensitive fungi, which may promote the ensuing loss of integrity in the plasma membrane. This direct effect on fungal membranes may contribute, at least in part, to the observed antimicrobial effects of these two salts. PMID:17337539

  4. Results of comparative assessment of US and Foreign Nuclear Power Plant dose experience and dose reduction programs

    SciTech Connect

    Baum, J.W.; Horan, J.R.; Dionne, B.J.

    1984-01-01

    Based on data evaluated to date it is clear that US plants have higher collective dose equivalents per reactor and per MW-y generated than most other countries. Factors which contribute to low doses include: (1) minimization of cobalt in primary system components exposed to water, (2) careful control of primary system oxygen and pH, (3) good primary system water purity to minimize corrosion product formation, (4) careful plant design, layout and component segration and shielding, (5) management interest and commitment, (6) minimum number of workers and in-depth worker training, (7) use of special tools, and (8) plant standardization. It should be pointed out that reductions in exposure are more difficult and costly in plants already built and operating. The cost-effectiveness of dose reduction efforts at US plants should be carefully evaluated before recommendations are made concerning existing plants.

  5. Selective Adsorption of Sodium Aluminum Fluoride Salts from Molten Aluminum

    SciTech Connect

    Leonard S. Aubrey; Christine A. Boyle; Eddie M. Williams; David H. DeYoung; Dawid D. Smith; Feng Chi

    2007-08-16

    Aluminum is produced in electrolytic reduction cells where alumina feedstock is dissolved in molten cryolite (sodium aluminum fluoride) along with aluminum and calcium fluorides. The dissolved alumina is then reduced by electrolysis and the molten aluminum separates to the bottom of the cell. The reduction cell is periodically tapped to remove the molten aluminum. During the tapping process, some of the molten electrolyte (commonly referred as “bath” in the aluminum industry) is carried over with the molten aluminum and into the transfer crucible. The carryover of molten bath into the holding furnace can create significant operational problems in aluminum cast houses. Bath carryover can result in several problems. The most troublesome problem is sodium and calcium pickup in magnesium-bearing alloys. Magnesium alloying additions can result in Mg-Na and Mg-Ca exchange reactions with the molten bath, which results in the undesirable pickup of elemental sodium and calcium. This final report presents the findings of a project to evaluate removal of molten bath using a new and novel micro-porous filter media. The theory of selective adsorption or removal is based on interfacial surface energy differences of molten aluminum and bath on the micro-porous filter structure. This report describes the theory of the selective adsorption-filtration process, the development of suitable micro-porous filter media, and the operational results obtained with a micro-porous bed filtration system. The micro-porous filter media was found to very effectively remove molten sodium aluminum fluoride bath by the selective adsorption-filtration mechanism.

  6. Reduction of noise generated by air conditioning and ventilation plants and transmitted to inhabited areas. [application of silencers

    NASA Technical Reports Server (NTRS)

    Harastaseanu, E.; Cristescu, G.; Mercea, F.

    1974-01-01

    The fans with which the conditioning and ventilation plants of weaving and spinning mills are equipped and the conditioning devices used in certain confection and knit wear departments of the textile industry generate loud noise. Solutions are presented for reducing the noise generated by the fans of ventilation and conditioning plants and transmitted to inhabited regions down to the admissible level, as well as the results obtained by experimental application of some noise reduction solutions in the conditioning plants of a spinning mill.

  7. Reduction of noise generated by air conditioning and ventilation plants and transmitted to inhabited areas. [application of silencers

    NASA Technical Reports Server (NTRS)

    Harastaseanu, E.; Cristescu, G.; Mercea, F.

    1974-01-01

    The fans with which the conditioning and ventilation plants of weaving and spinning mills are equipped and the conditioning devices used in certain confection and knit wear departments of the textile industry generate loud noise. Solutions are presented for reducing the noise generated by the fans of ventilation and conditioning plants and transmitted to inhabited regions down to the admissible level, as well as the results obtained by experimental application of some noise reduction solutions in the conditioning plants of a spinning mill.

  8. Aluminum Analysis.

    ERIC Educational Resources Information Center

    Sumrall, William J.

    1998-01-01

    Presents three problems based on the price of aluminum designed to encourage students to be cooperative and to use an investigative approach to learning. Students collect and synthesize information, analyze results, and draw conclusions. (AIM)

  9. Aluminum Analysis.

    ERIC Educational Resources Information Center

    Sumrall, William J.

    1998-01-01

    Presents three problems based on the price of aluminum designed to encourage students to be cooperative and to use an investigative approach to learning. Students collect and synthesize information, analyze results, and draw conclusions. (AIM)

  10. Wettability of Aluminum on Alumina

    NASA Astrophysics Data System (ADS)

    Bao, Sarina; Tang, Kai; Kvithyld, Anne; Tangstad, Merete; Engh, Thorvald Abel

    2011-12-01

    The wettability of molten aluminum on solid alumina substrate has been investigated by the sessile drop technique in a 10-8 bar vacuum or under argon atmosphere in the temperature range from 1273 K to 1673 K (1000 °C to 1400 °C). It is shown that the reduction of oxide skin on molten aluminum is slow under normal pressures even with ultralow oxygen potential, but it is enhanced in high vacuum. To describe the wetting behavior of the Al-Al2O3 system at lower temperatures, a semiempirical calculation was employed. The calculated contact angle at 973 K (700 °C) is approximately 97 deg, which indicates that aluminum does not wet alumina at aluminum casting temperatures. Thus, a priming height is required for aluminum to infiltrate a filter. Wetting in the Al-Al2O3 system increases with temperature.

  11. 78 FR 20298 - Restoration and Compensation Determination Plan and Environmental Assessment: Aluminum Production...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-04

    ... Environmental Assessment: Aluminum Production Plants and Engine Manufacturer, St. Lawrence River, Massena, NY... resource injuries and service losses associated with the release of hazardous substances from two aluminum... included polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), aluminum, fluoride, and...

  12. Smart LED lighting for major reductions in power and energy use for plant lighting in space

    NASA Astrophysics Data System (ADS)

    Poulet, Lucie

    Launching or resupplying food, oxygen, and water into space for long-duration, crewed missions to distant destinations, such as Mars, is currently impossible. Bioregenerative life-support systems under development worldwide involving photoautotrophic organisms offer a solution to the food dilemma. However, using traditional Earth-based lighting methods, growth of food crops consumes copious energy, and since sunlight will not always be available at different space destinations, efficient electric lighting solutions are badly needed to reduce the Equivalent System Mass (ESM) of life-support infrastructure to be launched and transported to future space destinations with sustainable human habitats. The scope of the present study was to demonstrate that using LEDs coupled to plant detection, and optimizing spectral and irradiance parameters of LED light, the model crop lettuce (Lactuca sativa L. cv. Waldmann's Green) can be grown with significantly lower electrical energy for plant lighting than using traditional lighting sources. Initial experiments aimed at adapting and troubleshooting a first-generation "smart" plant-detection system coupled to LED arrays resulted in optimizing the detection process for plant position and size to the limits of its current design. Lettuce crops were grown hydroponically in a growth chamber, where temperature, relative humidity, and CO2 level are controlled. Optimal irradiance and red/blue ratio of LED lighting were determined for plant growth during both lag and exponential phases of crop growth. Under optimizing conditions, the efficiency of the automatic detection system was integrated with LED switching and compared to a system in which all LEDs were energized throughout a crop-production cycle. At the end of each cropping cycle, plant fresh and dry weights and leaf area were measured and correlated with the amount of electrical energy (kWh) consumed. Preliminary results indicated that lettuce plants grown under

  13. [Noise-reduction function and its affecting factors of urban plant communities in Shanghai].

    PubMed

    Zhang, Qing-Fei; Zheng, Si-Jun; Xia, Lei; Wu, Hai-Ping; Zhang, Ming-Li; Li, Ming-Sheng

    2007-10-01

    The factor analysis on the relationships between excess noise attenuation (decrement after noise propagating 30 m) and 8 structural characteristics of 19 urban plant communities in Shanghai showed that all the plant communities had notable effects on reducing noise, and the noise attenuation ability of the communities was significantly higher than that of lawn (P < 0.01). The plant communities could be divided into three groups base on their noise attenuation ability, i.e., those of > or = 10 dB(A), 6-10 dB(A), and < or = 6 dB(A). The main factors affecting the noise attenuation ability of the communities were leaf area index, average bifurcate height, average height, coverage, and average canopy diameter, and their correlation coefficients with noise attenuation were 0.343, 0.318, 0.285, 0.226 and 0.193, respectively. These five factors had a cumulative contribution rate of 65.47%, suggesting that they should be considered in stress when designing urban greenbelt for noise reduction.

  14. Role of Reversible Histidine Coordination in Hydroxylamine Reduction by Plant Hemoglobins (Phytoglobins).

    PubMed

    Athwal, Navjot Singh; Alagurajan, Jagannathan; Andreotti, Amy H; Hargrove, Mark S

    2016-10-18

    Reduction of hydroxylamine to ammonium by phytoglobin, a plant hexacoordinate hemoglobin, is much faster than that of other hexacoordinate hemoglobins or pentacoordinate hemoglobins such as myoglobin, leghemoglobin, and red blood cell hemoglobin. The reason for differences in reactivity is not known but could be intermolecular electron transfer between protein molecules in support of the required two-electron reduction, hydroxylamine binding, or active site architecture favoring the reaction. Experiments were conducted with phytoglobins from rice, tomato, and soybean along with human neuroglobin and soybean leghemoglobin that reveal hydroxylamine binding as the rate-limiting step. For hexacoordinate hemoglobins, binding is limited by the dissociation rate constant for the distal histidine, while leghemoglobin is limited by an intrinsically low affinity for hydroxylamine. When the distal histidine is removed from rice phytoglobin, a hydroxylamine-bound intermediate is formed and the reaction rate is diminished, indicating that the distal histidine imidazole side chain is critical for the reaction, albeit not for electron transfer but rather for direct interaction with the substrate. Together, these results demonstrate that phytoglobins are superior at hydroxylamine reduction because they have distal histidine coordination affinity constants near 1, and facile rate constants for binding and dissociation of the histidine side chain. Hexacoordinate hemoglobins such as neuroglobin are limited by tighter histidine coordination that blocks hydroxylamine binding, and pentacoordinate hemoglobins have intrinsically lower hydroxylamine affinities.

  15. Evaluating best practices for Campylobacter and Salmonella reduction in poultry processing plants.

    PubMed

    Wideman, N; Bailey, M; Bilgili, S F; Thippareddi, H; Wang, L; Bratcher, C; Sanchez-Plata, M; Singh, M

    2016-02-01

    Poultry processing plants in the United States were surveyed on their current Campylobacter and Salmonella control practices. Following surveys, data were collected to develop a baseline for prevalence rates of Salmonella and Campylobacter; then changes in practices were implemented and evaluated for improvements in pathogen control. Surveys were sent to the plant Quality Assurance managers to determine production levels, antimicrobial interventions, and current pathogen testing practices. Initial sampling was performed at 6 plants with similar production volumes, at sites that included carcass samples before any pre-evisceration intervention, after exiting the inside-outside bird washer (IOBW), after exiting the pre-chiller, after exiting the primary chiller, and after exiting any post-chill intervention, as well as a water sample from each scalder, pre-chiller, primary chiller, and post-chill dip tank or finishing chiller. Enumerations and enrichments were performed for Campylobacter and Salmonella. Following the baseline sampling, changes in practices were suggested for each plant and a second sampling was conducted to determine their effectiveness. Results demonstrated that peracetic acid (PAA) was the most effective (P < 0.05) antimicrobial currently in use. The use of a post-chill antimicrobial immersion tank and/or use of a cetylpyridinium chloride (CPC) spray cabinet also displayed a further reduction in microbial levels (P < 0.05) when the primary chiller was not sufficient (P > 0.05). Microbial buildup in the immersion tanks demonstrates the need for effective cleaning, sanitation practices, and chiller maintenance to reduce contamination of poultry with Campylobacter and Salmonella. © 2015 Poultry Science Association Inc.

  16. Reductions in greenhouse gas (GHG) generation and energy consumption in wastewater treatment plants.

    PubMed

    Yerushalmi, L; Ashrafi, O; Haghighat, F

    2013-01-01

    Greenhouse gas (GHG) emission and energy consumption by on-site and off-site sources were estimated in two different wastewater treatment plants that used physical-chemical or biological processes for the removal of contaminants, and an anaerobic digester for sludge treatment. Physical-chemical treatment processes were used in the treatment plant of a locomotive repair factory that processed wastewater at 842 kg chemical oxygen demand per day. Approximately 80% of the total GHG emission was related to fossil fuel consumption for energy production. The emission of GHG was reduced by 14.5% with the recovery of biogas that was generated in the anaerobic digester and its further use as an energy source, replacing fossil fuels. The examined biological treatment system used three alternative process designs for the treatment of effluents from pulp and paper mills that processed wastewater at 2,000 kg biochemical oxygen demand per day. The three designs used aerobic, anaerobic, or hybrid aerobic/anaerobic biological processes for the removal of carbonaceous contaminants, and nitrification/denitrification processes for nitrogen removal. Without the recovery and use of biogas, the aerobic, anaerobic, and hybrid treatment systems generated 3,346, 6,554 and 7,056 kg CO(2)-equivalent/day, respectively, while the generated GHG was reduced to 3,152, 6,051, and 6,541 kg CO(2)-equivalent/day with biogas recovery. The recovery and use of biogas was shown to satisfy and exceed the energy needs of the three examined treatment plants. The reduction of operating temperature of the anaerobic digester and anaerobic reactor by 10°C reduced energy demands of the treatment plants by 35.1, 70.6 and 62.9% in the three examined treatment systems, respectively.

  17. Proteome analysis of roots of wheat seedlings under aluminum stress.

    PubMed

    Oh, Myeong Won; Roy, Swapan Kumar; Kamal, Abu Hena Mostofa; Cho, Kun; Cho, Seong-Woo; Park, Chul-Soo; Choi, Jong-Soon; Komatsu, Setsuko; Woo, Sun-Hee

    2014-02-01

    The root apex is considered the first sites of aluminum (Al) toxicity and the reduction in root biomass leads to poor uptake of water and nutrients. Aluminum is considered the most limiting factor for plant productivity in acidic soils. Aluminum is a light metal that makes up 7 % of the earth's scab dissolving ionic forms. The inhibition of root growth is recognized as the primary effect of Al toxicity. Seeds of wheat cv. Keumkang were germinated on petridish for 5 days and then transferred hydroponic apparatus which was treated without or with 100 and 150 μM AlCl3 for 5 days. The length of roots, shoots and fresh weight of wheat seedlings were decreased under aluminum stress. The concentration of K(+), Mg(2+) and Ca(2+) were decreased, whereas Al(3+) and P2O5 (-) concentration was increased under aluminum stress. Using confocal microscopy, the fluorescence intensity of aluminum increased with morin staining. A proteome analysis was performed to identify proteins, which are responsible to aluminum stress in wheat roots. Proteins were extracted from roots and separated by 2-DE. A total of 47 protein spots were changed under Al stress. Nineteen proteins were significantly increased such as sadenosylmethionine, oxalate oxidase, malate dehydrogenase, cysteine synthase, ascorbate peroxidase and/or, 28 protein spots were significantly decreased such as heat shock protein 70, O-methytransferase 4, enolase, and amylogenin. Our results highlight the importance and identification of stress and defense responsive proteins with morphological and physiological state under Al stress.

  18. Forest biomonitoring of the largest Slovene thermal power plant with respect to reduction of air pollution.

    PubMed

    Al Sayegh Petkovšek, Samar

    2013-02-01

    The condition of the forest ecosystem in the vicinity of the largest Slovene power plant [the Šoštanj Thermal Power Plant (ŠTPP)] was monitored during the period 1991-2008 by determining the total concentration of sulphur, ascorbic acid and chlorophyll in Norway spruce needles. After 1995, the introduction of cleaning devices at the ŠTPP dramatically reduced the former extremely high SO(2) and dust emissions. The most significant findings of this comprehensive, long-duration survey are as follows: (1) the chosen parameters are suitable bioindicators of stress caused by air pollution in Norway spruce needles; they reflect both spatial and temporal variations in air pollution as well as the degree of efficiency of the cleaning devices; (2) observations show that the physiological condition of Norway spruce in northern Slovenia has significantly improved since 1995, when the first desulphurization device at ŠTPP was built, together with a reduction in the area influenced by pollution from ŠTPP; (3) metabolic processes in spruce needles react to air pollution according to the severity of the pollution and the length of exposure; exposure to high SO(2) ambient levels and/or spread over a long duration can damage the antioxidant defence mechanisms of spruce trees as well as diminishing the concentration of ascorbic acid; (4) a reduction in the exposure to air pollution improves the vitality of the trees (e.g. higher concentrations of total (a + b) chlorophyll), as well as restoring their defence capabilities as shown by higher concentrations of ascorbic acid; and (5) forest monitoring should be continued and focused on integrating the effects of multiple stressors, which can additionally affect a forest ecosystem.

  19. Soil Oxidation-Reduction Potential and Plant Photosynthetic Capacity in the Northern Pantanal of Mato Grosso, Brazil

    NASA Astrophysics Data System (ADS)

    Lathuilliere, M. J.; Johnson, M. S.; Dalmagro, H. J.; Pinto Junior, O. B.; Couto, E. G.

    2013-12-01

    Plant communities of the Pantanal wetland are able to survive long periods of climatic and physiological stress in the dry and wet seasons. During inundation, soil oxygen demand increases dramatically as reducing soil conditions create stress in the root system with possible impacts on photosynthetic capacity of plants. We look at inundation cycles of a tree island (locally known as a cordilheira) in the Northern Pantanal near Poconé, Mato Grosso, and relate soil oxidation-reduction potential and soil oxygen depletion to the photosynthetic capacity of two plant communities of flooded scrub forest (Vochysia divergens and Curatela americana). Results show a drop in soil oxidation-reduction potential of over 400 mV, to levels below the absolute value of -200 mV, following inundation around the tree island. Both plant species showed increased carbon assimilation at highest soil oxygen demand despite a change in stomatal conductance, suggesting adaptation to the inundated environment. Absolute values of soil oxidation-reduction potential also allow for the determination of specific soil chemical reactions characteristic of the tree island environment, namely the reduction of iron(III), or carbon dioxide which in turn produces methane. Our combined analysis of soil chemistry with plant ecophysiology allows for a better understanding of soil-plant interactions in the Pantanal, specifically the drivers of biogeochemical processes between inundation periods.

  20. A plant-derived anti-nociceptive spray for reduction of pain with photodynamic therapy.

    PubMed

    Anseline, William; Grose, Douglas; Smith, Peter; Murray, Stephen; Messieh, Alfonse; Billing, Tania

    2014-12-01

    Photodynamic therapy is an effective tool in the management of some forms of skin cancer and generalized solar dermopathy and can be beneficial in the management of acne vulgaris. When used as an area treatment one of the main limiters is the quite severe burning pain that patients feel during the illumination phase of the treatment. To examine the effectiveness of a plant derived anti-nociceptive spray applied prior to and during large area photodynamic therapy. A split face or left arm versus right arm, placebo controlled trial was performed on 60 patients to assess the effectiveness of the spray in reducing pain perception. There was a statistically significant reduction in pain at all illumination points during the illumination phase but no significant difference in discomfort levels in the first 72 h post illumination. Only large area photodynamic therapy treatment was performed during the study. No conclusions can be drawn for small area treatments. Use of a simple, plant derived anti-nociceptive spray can reduce the discomfort experienced by patients undergoing photodynamic therapy to large areas. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Strategies for emission reduction of air pollutants produced from a chemical plant.

    PubMed

    Lee, Byeong-Kyu; Cho, Sung-Woong

    2003-01-01

    Various air pollution control (APC) techniques were employed in order to reduce emissions of air pollutants produced from chemical plants, which have many different chemical production facilities. For an emission reduction of acid gases, this study employed a method to improve solubility of pollutants by decreasing the operating temperature of the scrubbers, increasing the surface area for effective contact of gas and liquid, and modifying processes in the acid scrubbers. To reduce emission of both amines and acid gases, pollutant gas components were first separated, then condensation and/or acid scrubbing, depending on the chemical and physical properties of pollutant components, were used. To reduce emission of solvents, condensation and activated carbon adsorption were employed. To reduce emission of a mixture gases containing acid gases and solvents, the mixed gases were passed into the first condenser, the acid scrubber, the second condenser, and the activated carbon adsorption tower in sequence. As a strategy to reduce emission of pollutants at the source, this study also employed the simple pollution prevention concept of modification of the previously operating APC control device. Finally, air emissions of pollutants produced from the chemical plants were much more reduced by applying proper APC methods, depending upon the types (physical or chemical properties) and the specific emission situations of pollutants.

  2. Effects of pesticides on the reduction of plant and human pathogenic bacteria in application water.

    PubMed

    Mahovic, Michael; Gu, Ganyu; Rideout, Steven

    2013-04-01

    Overhead spray applications of in-field tomato treatments dissolved in aqueous solutions have specific pest targets (fungal, bacterial, insect, or other). Any organism present in the solution or on treated plant surfaces that is not a specific target of the application is unlikely inactivated and can instead be spread through the phyllosphere. In this laboratory study, commercially labeled pesticides (including Actigard 50WG, Bravo Weather Stik 6F, Cabrio 20EG, Kasumin, Kocide 3000 46WG, Oxidate 27L, Penncozeb 75DF, ProPhyt 54.5L, Stimplex 100L, Firewall, 22.4WP, and Tanos 50DF) in common use in commercial tomato production fields of the Eastern Shore of Virginia were investigated for activity against in vitro bacterial contamination of pesticide application waters. Pesticides of interest were tank mixed individually with one of the plant pathogens Ralstonia solanacearum, Xanthomonas campestris pv. vesicatoria, Pseudomonas syringae pv. tomato, Erwinia carotovora subsp. carotovora, or one of two serovars (Newport and Montevideo) of the human pathogen Salmonella enterica to assess reduction values during the average time between mixing and initial application. Observations suggested that while some treatments had a noticeable effect on population levels, only the oxidizer, peroxyacetic acid, showed significant and consistent levels of suppression against all bacteria investigated, at levels that could have practical implications.

  3. Hexavalent chromium reduction and plant growth promotion by Staphylococcusarlettae strain Cr11.

    PubMed

    Sagar, Sadhana; Dwivedi, Abhishek; Yadav, Suneel; Tripathi, Manishi; Kaistha, Shilpa Deshpande

    2012-02-01

    Cr(VI), a mutagenic and carcinogenic pollutant in industrial effluents, was effectively reduced by an indigenous tannery effluent isolate Staphylococcus arlettae strain Cr11 under aerobic conditions. The isolate could tolerate Cr(VI) up to 2000 and 5000 mg L(-1) in liquid and solid media respectively. S. arlettae Cr11 effectively reduced 98% of 100 mg L(-1) Cr(VI) in 24h. Reduction for initial Cr(VI) concentrations of 500 and 1000 mg L(-1) was 98% and 75%, respectively in 120 h. The isolate was also positive for siderophore, indole acetic acid, ammonia and catalase production, phosphate solubilization and biofilm formation in the presence and absence of Cr(VI). The isolate showed halotolerance (10% NaCl) and cross tolerance to other toxic heavy metals such as Hg(2+), Ni(2+), Cd(2+) and Pb(2+). Bacterial inoculation of Triticum aestivum in controlled petri dish and soil environment showed significant increase in percent germination, root and shoot length as well as dry and wet weight in Cr(VI) treated and untreated samples. This is the first report of simultaneous Cr(VI) reduction and plant growth promotion for a S. arlettae strain. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. A full scale worm reactor for efficient sludge reduction by predation in a wastewater treatment plant.

    PubMed

    Tamis, J; van Schouwenburg, G; Kleerebezem, R; van Loosdrecht, M C M

    2011-11-15

    Sludge predation can be an effective solution to reduce sludge production at a wastewater treatment plant. Oligochaete worms are the natural consumers of biomass in benthic layers in ecosystems. In this study the results of secondary sludge degradation by the aquatic Oligochaete worm Aulophorus furcatus in a 125 m(3) reactor and further sludge conversion in an anaerobic tank are presented. The system was operated over a period of 4 years at WWTP Wolvega, the Netherlands and was fed with secondary sludge from a low loaded activated sludge process. It was possible to maintain a stable and active population of the aquatic worm species A. furcatus during the full period. Under optimal conditions a sludge conversion of 150-200 kg TSS/d or 1.2-1.6 kg TSS/m(3)/d was established in the worm reactor. The worms grew as a biofilm on carrier material in the reactor. The surface specific conversion rate reached 140-180 g TSS/m(2)d and the worm biomass specific conversion rate was 0.5-1 g TSS sludge/g dry weight worms per day. The sludge reduction under optimal conditions in the worm reactor was 30-40%. The degradation by worms was an order of magnitude larger than the endogenous conversion rate of the secondary sludge. Effluent sludge from the worm reactor was stored in an anaerobic tank where methanogenic processes became apparent. It appeared that besides reducing the sludge amount, the worms' activity increased anaerobic digestibility, allowing for future optimisation of the total system by maximising sludge reduction and methane formation. In the whole system it was possible to reduce the amount of sludge by at least 65% on TSS basis. This is a much better total conversion than reported for anaerobic biodegradability of secondary sludge of 20-30% efficiency in terms of TSS reduction.

  5. Water quality limits for Atlantic salmon (Salmo salar L.) exposed to short term reductions in pH and increased aluminum simulating episodes

    NASA Astrophysics Data System (ADS)

    Kroglund, F.; Rosseland, B. O.; Teien, H.-C.; Salbu, B.; Kristensen, T.; Finstad, B.

    2008-03-01

    Acidification has caused the loss or reduction of numerous Atlantic salmon (Salmo salar L.) populations on both sides of the North Atlantic. Acid deposition peaked in the 1980's and resulted in both chronically and episodically acidified rivers. At present, water quality is improving in all affected rivers due to reduced acid deposition. However, spring snow melt, heavy rainfall and sea salt episodes can still cause short term drops in pH and elevated concentrations of bioavailable aluminum. Technical malfunction in lime dozers will cause short termed episodic spates in the limed rivers. The current situation has prompted a need for dose-response relationships based on short term exposures of Atlantic salmon to assess the potential population effects of episodic acidification. Water quality guidelines for salmon have been lacking, despite a large number of experiments, all demonstrating dose-response relationships between water chemistry and fish health. We have summarized results from 347 short-term (<14 days) exposures of salmon parr and smolt performed between 1990 and 2003 in Norway. The experiments have been performed as bioassays, where fish have been exposed in tanks fed river water, in tanks where the river water quality has been manipulated (added H+ and Al) and as Carlin-tagged smolt releases after preexposure to moderately acidic waters. The results from the various bioassays are compared to water quality limits proposed on basis of the relationship between water quality and population status/health in Norwegian rivers. The focus of this article is placed on chemical-biological interactions that can be drawn across experiments and exposure protocols. We propose dose-response relationships for acid neutralizing capacity (ANC), pH, cationic Al and gill accumulated Al, versus mortality in freshwater, effects on hypo-osmoregulatory capacity in seawater challenge tests and on smolt to adult survival in release experiments. The "no effect" dose depends on the

  6. Water quality limits for Atlantic salmon (Salmo salar L.) exposed to short term reductions in pH and increased aluminum simulating episodes

    NASA Astrophysics Data System (ADS)

    Kroglund, F.; Rosseland, B. O.; Teien, H.-C.; Salbu, B.; Kristensen, T.; Finstad, B.

    2007-09-01

    Acidification has caused the loss or reduction of numerous Atlantic salmon (Salmo salar L.) populations on both sides of the North Atlantic. Acid deposition peaked in the 1980's and resulted in both chronically and episodically acidified rivers. At present, water quality is improving in all affected rivers due to reduced acid deposition. However, spring snow melt, heavy rainfall and sea salt episodes can still cause short term drops in pH and elevated concentrations of bioavailable aluminum. Technical malfunction in lime dozers will cause short termed episodic spates in the limed rivers. The current situation has prompted a need for dose-response relationships based on short term exposures of Atlantic salmon to assess the potential population effects of episodic acidification. Water quality guidelines for salmon have been lacking, despite a large number of experiments, all demonstrating dose-response relationships between water chemistry and fish health. We have summarized results from 347 short-term (<14 days) exposures of salmon parr and smolt performed between 1990 and 2003 in Norway. The experiments have been performed as bioassays, where fish have been exposed in tanks fed river water, in tanks where the river water quality has been manipulated (added H+ and Al) and as Carlin-tagged smolt releases after preexposure to moderately acidic waters. The results from the various bioassays are compared to water quality limits proposed on basis of the relationship between water quality and population status/health in Norwegian rivers. The focus of this article is placed on chemical-biological interactions that can be drawn across experiments and exposure protocols. We propose dose-response relationships for acid neutralizing capacity (ANC), pH, cationic Al and gill accumulated Al, versus mortality in freshwater, effects on hypo-osmoregulatory capacity in seawater challenge tests and on smolt to adult survival in release experiments. The "no effect" dose depends on the

  7. Aluminum alloy

    NASA Technical Reports Server (NTRS)

    Blackburn, Linda B. (Inventor); Starke, Edgar A., Jr. (Inventor)

    1989-01-01

    This invention relates to aluminum alloys, particularly to aluminum-copper-lithium alloys containing at least about 0.1 percent by weight of indium as an essential component, which are suitable for applications in aircraft and aerospace vehicles. At least about 0.1 percent by weight of indium is added as an essential component to an alloy which precipitates a T1 phase (Al2CuLi). This addition enhances the nucleation of the precipitate T1 phase, producing a microstructure which provides excellent strength as indicated by Rockwell hardness values and confirmed by standard tensile tests.

  8. Aluminum alloy

    NASA Technical Reports Server (NTRS)

    Blackburn, Linda B. (Inventor); Starke, Edgar A., Jr. (Inventor)

    1989-01-01

    This invention relates to aluminum alloys, particularly to aluminum-copper-lithium alloys containing at least about 0.1 percent by weight of indium as an essential component, which are suitable for applications in aircraft and aerospace vehicles. At least about 0.1 percent by weight of indium is added as an essential component to an alloy which precipitates a T1 phase (Al2CuLi). This addition enhances the nucleation of the precipitate T1 phase, producing a microstructure which provides excellent strength as indicated by Rockwell hardness values and confirmed by standard tensile tests.

  9. Microstructure of SiC-Si-Al2O3 composites derived from silicone resin - metal aluminum filler compounds by low temperature reduction process

    NASA Astrophysics Data System (ADS)

    Narisawa, M.; Abe, Y.

    2011-06-01

    Concentrated slurry of a silicone resin with low carbon content, 3 μm aluminum particles and ethanol were prepared. After casting, addition of cross-linking agent and drying, silicone resin-aluminum composite with thick sheet form was obtained. The prepared sheet was heat-treated at 933 or 1073K with various holding times to characterize formed phases during the heat treatments. XRD patterns and FT-IR spectra revealed free Si formation and existence of Si-O-Si bond at 933K. The Si-O-Si bond, however, disappeared and silicon carbide was formed at 1073K. SEM observation indicated formation of cracks bridged with a number of tiny struts at 933K and conversion to wholly porous structure at 1073K.

  10. Aluminum phosphide

    Integrated Risk Information System (IRIS)

    Aluminum phosphide ; CASRN 20859 - 73 - 8 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

  11. Limits to Understory Plant Restoration Following Fuel-Reduction Treatments in a Piñon-Juniper Woodland

    NASA Astrophysics Data System (ADS)

    Redmond, Miranda D.; Zelikova, Tamara J.; Barger, Nichole N.

    2014-11-01

    National fuel-reduction programs aim to reduce the risk of wildland fires to human communities and to restore forest and rangeland ecosystems to resemble their historical structure, function, and diversity. There are a number of factors, such as seed bank dynamics, post-treatment climate, and herbivory, which determine whether this latter goal may be achieved. Here, we examine the short-term (2 years) vegetation response to fuel-reduction treatments (mechanical mastication, broadcast burn, and pile burn) and seeding of native grasses on understory vegetation in an upland piñon-juniper woodland in southeast Utah. We also examine how wildlife herbivory affects the success of fuel-reduction treatments. Herbaceous cover increased in response to fuel-reduction treatments in all seeded treatments, with the broadcast burn and mastication having greater increases (234 and 160 %, respectively) in herbaceous cover than the pile burn (32 %). In the absence of seeding, herbaceous cover only increased in the broadcast burn (32 %). Notably, fuel-reduction treatments, but not seeding, strongly affected herbaceous plant composition. All fuel-reduction treatments increased the relative density of invasive species, especially in the broadcast burn, which shifted the plant community composition from one dominated by perennial graminoids to one dominated by annual forbs. Herbivory by wildlife reduced understory plant cover by over 40 % and altered plant community composition. If the primary management goal is to enhance understory cover while promoting native species abundance, our study suggests that mastication may be the most effective treatment strategy in these upland piñon-juniper woodlands. Seed applications and wildlife exclosures further enhanced herbaceous cover following fuel-reduction treatments.

  12. Limits to understory plant restoration following fuel-reduction treatments in a piñon-juniper woodland.

    PubMed

    Redmond, Miranda D; Zelikova, Tamara J; Barger, Nichole N

    2014-11-01

    National fuel-reduction programs aim to reduce the risk of wildland fires to human communities and to restore forest and rangeland ecosystems to resemble their historical structure, function, and diversity. There are a number of factors, such as seed bank dynamics, post-treatment climate, and herbivory, which determine whether this latter goal may be achieved. Here, we examine the short-term (2 years) vegetation response to fuel-reduction treatments (mechanical mastication, broadcast burn, and pile burn) and seeding of native grasses on understory vegetation in an upland piñon-juniper woodland in southeast Utah. We also examine how wildlife herbivory affects the success of fuel-reduction treatments. Herbaceous cover increased in response to fuel-reduction treatments in all seeded treatments, with the broadcast burn and mastication having greater increases (234 and 160 %, respectively) in herbaceous cover than the pile burn (32 %). In the absence of seeding, herbaceous cover only increased in the broadcast burn (32 %). Notably, fuel-reduction treatments, but not seeding, strongly affected herbaceous plant composition. All fuel-reduction treatments increased the relative density of invasive species, especially in the broadcast burn, which shifted the plant community composition from one dominated by perennial graminoids to one dominated by annual forbs. Herbivory by wildlife reduced understory plant cover by over 40 % and altered plant community composition. If the primary management goal is to enhance understory cover while promoting native species abundance, our study suggests that mastication may be the most effective treatment strategy in these upland piñon-juniper woodlands. Seed applications and wildlife exclosures further enhanced herbaceous cover following fuel-reduction treatments.

  13. Georgia-Pacific Palatka Plant Uses Thermal Pinch Analysis and Evaluates Water Reduction in Plant-Wide Energy Assessment

    SciTech Connect

    2002-12-01

    This OIT BestPractices Case Study describes the methods and results used in a plant-wide assessment at a Georgia-Pacific paper mill in Palatka, FL. Assessment personnel recommended several projects, which, if implemented, have the potential to save the plant more than 729,000 MMBtu per year and $2.9 million per year. In addition, the plant could reduce water use by 2,100 gallons per minute.

  14. Odour reduction strategies for biosolids produced from a Western Australian wastewater treatment plant: results from Phase I laboratory trials.

    PubMed

    Gruchlik, Yolanta; Heitz, Anna; Joll, Cynthia; Driessen, Hanna; Fouché, Lise; Penney, Nancy; Charrois, Jeffrey W A

    2013-01-01

    This study investigated sources of odours from biosolids produced from a Western Australian wastewater treatment plant and examined possible strategies for odour reduction, specifically chemical additions and reduction of centrifuge speed on a laboratory scale. To identify the odorous compounds and assess the effectiveness of the odour reduction measures trialled in this study, headspace solid-phase microextraction gas chromatography-mass spectrometry (HS SPME-GC-MS) methods were developed. The target odour compounds included volatile sulphur compounds (e.g. dimethyl sulphide, dimethyl disulphide and dimethyl trisulphide) and other volatile organic compounds (e.g. toluene, ethylbenzene, styrene, p-cresol, indole and skatole). In our laboratory trials, aluminium sulphate added to anaerobically digested sludge prior to dewatering offered the best odour reduction strategy amongst the options that were investigated, resulting in approximately 40% reduction in the maximum concentration of the total volatile organic sulphur compounds, relative to control.

  15. Effect of power plant emission reductions on a nearby wilderness area: a case study in northwestern Colorado

    USGS Publications Warehouse

    Mast, M. Alisa; Ely, Daniel

    2013-01-01

    This study evaluates the effect of emission reductions at two coal-fired power plants in northwestern Colorado on a nearby wilderness area. Control equipment was installed at both plants during 1999–2004 to reduce SO2 and NOx emissions. One challenge was separating the effects of local from regional emissions, which also declined during the study period. The long-term datasets examined confirm that emission reductions had a beneficial effect on air and water quality in the wilderness. Despite a 75 % reduction in SO2 emissions, sulfate aerosols measured in the wilderness decreased by only 20 %. Because the site is relatively close to the power plants (2 to sulfate, particularly under conditions of low relative humidity, might account for this less than one-to-one response. On the clearest days, emissions controls appeared to improve visibility by about 1 deciview, which is a small but perceptible improvement. On the haziest days, however, there was little improvement perhaps reflecting the dominance of regional haze and other components of visibility degradation particularly organic carbon and dust. Sulfate and acidity in atmospheric deposition decreased by 50 % near the southern end of the wilderness of which 60 % was attributed to power plant controls and the remainder to reductions in regional sources. Lake water sulfate responded rapidly to trends in deposition declining at 28 lakes monitored in and near the wilderness. Although no change in the acid–base status was observed, few of the lakes appear to be at risk from chronic or episodic acidification.

  16. Alternatives to Methyl bromide studies in Gainesville 2001-2008: Summary of emissions reduction studies of pre-plant soil

    USDA-ARS?s Scientific Manuscript database

    Reducing emissions of pre-plant soil fumigants is important because EPA is proposing untreated buffer zones around fields for injection applications of current fumigants. Credits will be given to proven emissions reductions practices that would decrease the downwind off-site concentrations of fumiga...

  17. ALTERNATIVES TO METHYL BROMIDE STUDIES IN GAINESVILLE 2001-2008: SUMMARY OF EMISSIONS REDUCTION STUDIES OF PRE-PLANT SOIL

    USDA-ARS?s Scientific Manuscript database

    Reducing emissions of pre-plant soil fumigants is important because EPA is proposing untreated buffer zones around fields for injection applications of current fumigants. Credits will be given to proven emissions reductions practices that would decrease the downwind off-site concentrations of fumiga...

  18. Neurobehavioral testing of subjects exposed residentially to groundwater contaminated from an aluminum die-casting plant and local referents

    SciTech Connect

    Kilburn, K.H.; Warshaw, R.H. )

    1993-08-01

    Residents adjoining a die-casting plant had excessive headaches, numbness of hands and feet, dizziness, blurred vision, staggering, sweating, abnormal heart rhythm, and depression, which led to measurements of neurobehavioral performance, affective status, and the frequency of symptoms. They had all been exposed via well water and proximity to the plant to volatile organic chemicals (VOC) and to polychlorinated biphenyls (PCBs). The 117 exposed women and men and 46 unexposed referents were studied together for simple and choice visual reaction time, body sway speed, blink reflex latency, color discrimination, Culture Fair (a nonverbal nonarithmetic intelligence test), recall of stories, figures, and numbers, cognitive and psychomotor control (slotted pegboard and trail making A and B), long-term memory, profile of mood states (POMS), and scores and frequencies of 34 symptoms. Choice reaction time, sway speed, and blink latency were impaired in both sexes of the exposed group and trail making B was impaired in exposed women. The POMS scores and frequencies of 30 of 34 symptoms were elevated in both sexes, compared to referents. Recall, long-term memory, psychomotor speed, and other cognitive function tests were reduced in exposed subjects and in the referents as compared to national referents. Neurophysiological impairment, and cognitive and psychomotor dysfunction and affective disorders, especially depression and excessive frequency of symptoms, were associated with the use of wells contaminated with VOCs, TCE and PCBs.

  19. SUMMARY CONCLUSIONS FOR THE PILOT IN-SITU CHROMIUM REDUCTION TEST AT RIVERBANK ARMY AMMUNITIONS PLANT

    SciTech Connect

    Ridley, M

    2007-04-25

    A treatability study was conducted at Riverbank Army Ammunition Plant's (RBAAP) Site 17, to evaluate the effectiveness of a permeable reactive barrier (PRB) for the treatment of hexavalent chromium (Cr{sup 6+}). The chromium contamination at Site 17 is hydrologically isolated and unsuitable for standard extraction and treatment (pump and treat). The majority of the chromium contamination at Site 17 is trapped within the fine grain sediments of a clay/slit zone (45 to 63). The PRB was established above and adjacent to the contaminated zone at Site 17 to reduce the hexavalent chromium as it leaches out of the contaminated clay/silt zone separating the A zone from the A zone. Site 17 and the monitoring network are described in the In-Situ Chromium Reduction Treatability Study Work Plan (CH2MHILL, January 2004). The PRB was created by reducing naturally occurring Fe{sup 3+} to Fe{sup 2+} with the injection of a buffered sodium dithionite solution into subsurface chromium source area. The Cr{sup 6+} leaching out of the contaminated clay/silt zone and migrating through the PRB is reduced by Fe{sup 2+} to Cr{sup 3+} and immobilized (Amonette, et al., 1994). The sodium dithionite will also reduce accessible Cr{sup 6+}, however the long-term reductant is the Fe{sup 2+}. Bench scale tests (Appendix A) were conducted to assess the quantity and availability of the naturally occurring iron at Site 17, the ability of the sodium dithionite to reduce the hexavalent chromium and Fe within the sediments, and the by-products produced during the treatment. Appendix A, provides a detailed description of the laboratory treatability tests, and provides background information on the technologies considered as possible treatment options for Site 17. Following the sodium dithionite treatment, groundwater/treatment solution was extracted to remove treatment by-products (sulfate, manganese, and iron). The following sections briefly discuss the current treatment status, future recommendations

  20. Comparative estimation of soil and plant pollution in the impact area of air emissions from an aluminium plant after technogenic load reduction.

    PubMed

    Evdokimova, Galina A; Mozgova, Natalya P

    2015-01-01

    The work provides a comparative analysis of changes in soil properties in the last 10-13 years along the pollution gradient of air emissions from Kandalaksha aluminium plant in connection with the reduction of their volume. The content of the priority pollutant fluorine (F) in atmospheric precipitation and in the organic horizon of soil in the plant impact zone significantly decreased in 2011-2013 compared to 2001. The aluminium concentrations reduced only in immediate proximity to the plant (2 km). The fluorine, calcium (Ca) and magnesium (Mg) concentrations are higher in liquid phase compared to solid phase thus these elements can migrated to greater distances from the pollution source (up to 15-20 km). Silicon (Si), aluminium (Al), iron (Fe) and phosphorus (P) can be found only in solid phases and in fall-out within the 5 km. The acidity of soil litter reduced by 2 pH units in the proximity to the plot within the 2 km. The zone of maximum soil contamination decreased from 2.5 km to 1.5 km from the emission source, the zones of heavy and moderate pollution reduced by 5 km in connection with the reduction of pollutant emissions in the plant. A high correlation between the fluorine concentrations in vegetables and litter was found. Higher fluorine concentrations in the soil result in its accumulation in plants. Mosses accumulate fluorine most intensively.

  1. Genome size reduction can trigger rapid phenotypic evolution in invasive plants

    PubMed Central

    Lavergne, Sébastien; Muenke, Nikolas J.; Molofsky, Jane

    2010-01-01

    Background and Aims The study of rapid evolution in invasive species has highlighted the fundamental role played by founder events, emergence of genetic novelties through recombination and rapid response to new selective pressures. However, whether rapid adaptation of introduced species can be driven by punctual changes in genome organization has received little attention. In plants, variation in genome size, i.e. variation in the amount of DNA per monoploid set of chromosomes through loss or gain of repeated DNA sequences, is known to influence a number of physiological, phenological and life-history features. The present study investigated whether change in genome size has contributed to the evolution of greater potential of vegetative growth in invasive populations of an introduced grass. Methods The study was based on the recent demonstration that invasive genotypes of reed canarygrass (Phalaris arundinacea) occurring in North America have emerged from recombination between introduced European strains. The genome sizes of more than 200 invasive and native genotypes were measured and their genome size was related to their phenotypic traits measured in a common glasshouse environment. Population genetics data were used to infer phylogeographical relationships between study populations, and the evolutionary history of genome size within the study species was inferred. Key Results Invasive genotypes had a smaller genome than European native genotypes from which they are derived. This smaller genome size had phenotypic effects that increased the species' invasive potential, including a higher early growth rate, due to a negative relationship between genome size and rate of stem elongation. Based on inferred phylogeographical relationships of invasive and native populations, evolutionary models were consistent with a scenario of genome reduction by natural selection during the invasion process, rather than a scenario of stochastic change. Conclusions Punctual

  2. [Link between aluminum neurotoxicity and neurodegenerative disorders].

    PubMed

    Kawahara, Masahiro

    2016-07-01

    Aluminum is an old element that has been known for a long time, but some of its properties are only now being discovered. Although environmentally abundant, aluminum is not essential for life; in fact, because of its specific chemical properties, aluminum inhibits more than 200 biologically important functions and exerts various adverse effects in plants, animals, and humans. Aluminum is a widely recognized neurotoxin. It has been suggested that there is a relationship between exposure to aluminum and neurodegenerative diseases, including dialysis encephalopathy, amyotrophic lateral sclerosis and parkinsonism dementia in the Kii Peninsula and Guam, as well as Alzheimer' s disease: however, this claim remains to be verified. In this chapter, we review the detailed characteristics of aluminum neurotoxicity and the link between Alzheimer' s disease and other neurodegenerative diseases, based on recent findings on metal-metal interactions and the functions of metalloproteins in synapses.

  3. Aluminum welding fume-induced pneumoconiosis.

    PubMed

    Hull, Mindy J; Abraham, Jerrold L

    2002-08-01

    Chronic exposure to high concentrations of fumes during aluminum arc welding causes a severe pneumoconiosis characterized by diffuse pulmonary accumulation of aluminum metal and a corresponding reduction in lung function. Aluminum fume-induced pneumoconiosis is a rarely reported entity, of which the true incidence is unknown. We report the clinical, radiographic, microscopic, and microanalytic results of 2 coworkers, employed by the same aluminum shipbuilding facility, who died of complications from this disease. Scanning electron microscopy and energy dispersive x-ray analysis of the exogenous particle content in the lung tissue of these cases revealed the highest concentrations of aluminum particles (average of 9.26 billion aluminum particles per cm(3) of lung tissue) among the 812 similar analyses in our pneumoconiosis database. One patient had an original clinical diagnosis of sarcoidosis but no evidence of granulomatous inflammation. Copyright 2002, Elsevier Science (USA). All rights reserved.

  4. TOXICITY REDUCTION EVALUATION (TRE) AT A MUNICIPAL WASTEWATER TREATMENT PLANT USING MUTAGENICITY AS AN END- POINT

    EPA Science Inventory

    Previous work revealed substantial levels of mutagenicity in effluents from certain municipal wastewater treatment plants. One of these treatment plants was selected for further study to track the effluent mutagenicity to its sources, to chemically characterize the mutagenicity, ...

  5. TOXICITY REDUCTION EVALUATION (TRE) AT A MUNICIPAL WASTEWATER TREATMENT PLANT USING MUTAGENICITY AS AN END- POINT

    EPA Science Inventory

    Previous work revealed substantial levels of mutagenicity in effluents from certain municipal wastewater treatment plants. One of these treatment plants was selected for further study to track the effluent mutagenicity to its sources, to chemically characterize the mutagenicity, ...

  6. Aluminum toxicity is associated with mitochondrial dysfunction and the production of reactive oxygen species in plant cells.

    PubMed

    Yamamoto, Yoko; Kobayashi, Yukiko; Devi, S Rama; Rikiishi, Sanae; Matsumoto, Hideaki

    2002-01-01

    Potential mechanisms of Al toxicity measured as Al-induced inhibition of growth in cultured tobacco cells (Nicotiana tabacum, nonchlorophyllic cell line SL) and pea (Pisum sativum) roots were investigated. Compared with the control treatment without Al, the accumulation of Al in tobacco cells caused instantaneously the repression of mitochondrial activities [monitored by the reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide and the uptake of Rhodamine 123] and, after a lag of about 12 h, triggered reactive oxygen species (ROS) production, respiration inhibition, ATP depletion, and the loss of growth capability almost simultaneously. The presence of an antioxidant, butylated hydroxyanisol, during Al treatment of SL cells prevented not only ROS production but also ATP depletion and the loss of growth capability, suggesting that the Al-triggered ROS production seems to be a cause of ATP depletion and the loss of growth capability. Furthermore, these three late events were similarly repressed in an Al-tolerant cell line (ALT301) isolated from SL cells, suggesting that the acquisition of antioxidant functions mimicking butylated hydroxyanisol can be a mechanism of Al tolerance. In the pea root, Al also triggered ROS production, respiration inhibition, and ATP depletion, which were all correlated with inhibition of root elongation. Taken together, we conclude that Al affects mitochondrial functions, which leads to ROS production, probably the key critical event in Al inhibition of cell growth.

  7. Over-expression of Arabidopsis CAP causes decreased cell expansion leading to organ size reduction in transgenic tobacco plants.

    PubMed

    Barrero, Roberto A; Umeda, Masaaki; Yamamura, Saburo; Uchimiya, Hirofumi

    2003-04-01

    Cyclase-associated proteins (CAP) are multifunctional proteins involved in Ras-cAMP signalling and regulation of the actin cytoskeleton. It has recently been demonstrated that over-expression of AtCAP1 in transgenic arabidopsis plants causes severe morphological defects owing to loss of actin filaments. To test the generality of the function of AtCAP1 in plants, transgenic tobacco plants over-expressing an arabidopsis CAP (AtCAP1) under the regulation of a glucocorticoid-inducible promoter were produced. Over-expression of AtCAP1 in transgenic tobacco plants led to growth abnormalities, in particular a reduction in the size of leaves. Morphological alterations in leaves were the result of reduced elongation of epidermal and mesophyll cells.

  8. Energy savings through the use of an improved aluminum reduction-cell cathode. Technical progress report, April 1, 1980-June 30, 1980

    SciTech Connect

    Dorward, R.C.; Payne, J.R.

    1980-08-05

    Goal is to develop a Hall cell cathode, which will reduce the specific energy consumption of existing commercial cells by 20 to 25%. Basis of the improvement is the utilization of titanium diboride (TiB/sub 2/), a material that is wetted by molten aluminum, as the cell cathode. This provides a stable cathode surface, thereby allowing the cell to be operated at a smaller anode-cathode distance (ACD). Energy savings arise as a result of reduced resistive losses through the cryolite electrolyte. This phase of the program is comprised of three integrated parts: (1) materials characterization, (2) pilot cell testing, and (3) a full-sized cell demonstration. During this quarter emphasis continued on rebuilding the 15KA pilot cell to accommodate a highly sloped electrode system. TiB/sub 2/ cathode materials were received, and construction of cell components and peripheral equipment was completed.

  9. Synthesis of Al-Zr Alloys Via ZrO2 Aluminum-Thermal Reduction in KF-AlF3-Based Melts

    NASA Astrophysics Data System (ADS)

    Pershin, Pavel S.; Kataev, A. A.; Filatov, A. A.; Suzdaltsev, A. V.; Zaikov, Yu. P.

    2017-08-01

    Physical-chemical investigations of KF-AlF3 melts were carried out in order to develop the scientific basis of the technology for Al-Zr alloy synthesis. The possibility of Al-Zr alloy synthesis via the aluminum-thermal method was shown. The liquidus temperatures of KF-AlF3 and KF-NaF-AlF3 melts with additions of Al2O3 and ZrO2 were determined using the thermal analysis method in the temperature range from 873 K to 1173 K (600 °C to 900 °C). The dependency of the solubility of ZrO2 in KF-AlF3 and KF-NaF-AlF3 melts on Al2O3 concentration was measured.

  10. Brazing dissimilar aluminum alloys

    NASA Technical Reports Server (NTRS)

    Dalalian, H.

    1979-01-01

    Dip-brazing process joins aluminum castings to aluminum sheet made from different aluminum alloy. Process includes careful cleaning, surface preparation, and temperature control. It causes minimum distortion of parts.

  11. Scaleable Clean Aluminum Melting Systems

    SciTech Connect

    Han, Q.; Das, S.K.

    2008-02-15

    The project entitled 'Scaleable Clean Aluminum Melting Systems' was a Cooperative Research and Development Agreements (CRADAs) between Oak Ridge National Laboratory (ORNL) and Secat Inc. The three-year project was initially funded for the first year and was then canceled due to funding cuts at the DOE headquarters. The limited funds allowed the research team to visit industrial sites and investigate the status of using immersion heaters for aluminum melting applications. Primary concepts were proposed on the design of furnaces using immersion heaters for melting. The proposed project can continue if the funding agency resumes the funds to this research. The objective of this project was to develop and demonstrate integrated, retrofitable technologies for clean melting systems for aluminum in both the Metal Casting and integrated aluminum processing industries. The scope focused on immersion heating coupled with metal circulation systems that provide significant opportunity for energy savings as well as reduction of melt loss in the form of dross. The project aimed at the development and integration of technologies that would enable significant reduction in the energy consumption and environmental impacts of melting aluminum through substitution of immersion heating for the conventional radiant burner methods used in reverberatory furnaces. Specifically, the program would couple heater improvements with furnace modeling that would enable cost-effective retrofits to a range of existing furnace sizes, reducing the economic barrier to application.

  12. Carbothermal synthesis of aluminum nitride

    SciTech Connect

    Silverman, L.D. )

    1988-07-01

    A synthetic route is described for making carbothermally reduced powders from colloidal oxide precursors trapped in a polymer matrix. The entrapping resin, which is formed by polymerization of a monomer dissolved in the colloid, serves both to minimize particle agglomeration during reaction and as the source of carbon for reduction. Following reduction, the remaining carbon matrix is removed by oxidation. This strategy was used to synthesize aluminum nitride powder via trapping of colloidal alumina in poly(furfuryl alcohol) resin.

  13. Production of aluminum-silicon alloy and ferrosilicon and commercial purity aluminum by the direct reduction process. First interim technical report, Phase C for the period 1980 January 1-1980 March 31

    SciTech Connect

    Bruno, M.J.

    1980-10-01

    Pilot reactor VSR-3 was operated with 75 to 120 SCFH O/sub 2/ to supply part of the process heat requirements by combustion of coke. No alloy was made and burden bridging persistently stopped operations. Burning larger coke particles, -3/8 in. +6 mesh, with O/sub 2/ injected through a larger diameter tuyere orifice resulted in oxygen attack on the reactor graphite liner. Updated thermochemical data for Al/sub 2/O/sub 3/ significantly changed the calculated reflux loading for a one-atm blast furnace, predicting almost total reflux and no alloy recovery. Based on these calculations and the experimental problems with combustion heated operation, VSR-3 was modified to study an alternate reduction concept - the blast-arc - which utilizes combustion heat to reduce SiO/sub 2/ to SiC at 1600/sup 0/C, and electrical heat to complete the reduction of Al/sub 2/O/sub 3/ and the production of alloy. Design, fabrication, and installation of most of the pilot crystallizer sytem was completed.

  14. Methyl jasmonate promotes the transient reduction of the levels of 2-Cys peroxiredoxin in Ricinus communis plants.

    PubMed

    dos Santos Soares, Alexandra Martins; de Souza, Thiago Freitas; de Souza Domingues, Sarah Jane; Jacinto, Tânia; Tavares Machado, Olga Lima

    2004-06-01

    Jasmonates are signaling molecules that play a key role in the regulation of metabolic processes, reproduction and defense against insects and pathogens. This study investigated the effects of methyl jasmonate on the protein pattern of Ricinus communis plants and the activity of guaiacol peroxidase, an antioxidant enzyme. Methyl jasmonate treatment caused a transient reduction in guaiacol peroxidase activity. A similar response was observed for the levels of 2-Cys peroxiredoxin protein. Moreover, the levels of the small and large chains of Rubisco were also reduced. The transient reduction of the levels and activity of antioxidant enzymes could account for the increase in the levels of H2O2, an important signaling molecule in plant defense.

  15. Recent Large Reduction in Sulfur Dioxide Emissions from Chinese Power Plants Observed by the Ozone Monitoring Instrument

    NASA Technical Reports Server (NTRS)

    Li, Can; Zhang, Qiang; Krotkov, Nickolay A.; Streets, David G.; He, Kebin; Tsay, Si-Chee; Gleason, James F.

    2010-01-01

    The Ozone Monitoring Instrument (OMI) aboard NASA's Aura satellite observed substantial increases in total column SO2 and tropospheric column NO2 from 2005 to 2007, over several areas in northern China where large coal-fired power plants were built during this period. The OMI-observed SO2/NO2 ratio is consistent with the SO2/ NO2, emissions estimated from a bottom-up approach. In 2008 over the same areas, OMI detected little change in NO2, suggesting steady electricity output from the power plants. However, dramatic reductions of S0 2 emissions were observed by OMI at the same time. These reductions confirm the effectiveness of the flue-gas desulfurization (FGD) devices in reducing S02 emissions, which likely became operational between 2007 and 2008. This study further demonstrates that the satellite sensors can monitor and characterize anthropogenic emissions from large point sources.

  16. Recent Large Reduction in Sulfur Dioxide Emissions from Chinese Power Plants Observed by the Ozone Monitoring Instrument

    NASA Technical Reports Server (NTRS)

    Li, Can; Zhang, Qiang; Krotkov, Nickolay A.; Streets, David G.; He, Kebin; Tsay, Si-Chee; Gleason, James F.

    2010-01-01

    The Ozone Monitoring Instrument (OMI) aboard NASA's Aura satellite observed substantial increases in total column SO2 and tropospheric column NO2 from 2005 to 2007, over several areas in northern China where large coal-fired power plants were built during this period. The OMI-observed SO2/NO2 ratio is consistent with the SO2/ NO2, emissions estimated from a bottom-up approach. In 2008 over the same areas, OMI detected little change in NO2, suggesting steady electricity output from the power plants. However, dramatic reductions of S0 2 emissions were observed by OMI at the same time. These reductions confirm the effectiveness of the flue-gas desulfurization (FGD) devices in reducing S02 emissions, which likely became operational between 2007 and 2008. This study further demonstrates that the satellite sensors can monitor and characterize anthropogenic emissions from large point sources.

  17. 40 CFR 52.2500 - Best available retrofit technology requirements for the Intalco Aluminum Corporation (Intalco...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... requirements for the Intalco Aluminum Corporation (Intalco Works) primary aluminum plant-Better than BART... Best available retrofit technology requirements for the Intalco Aluminum Corporation (Intalco Works) primary aluminum plant—Better than BART Alternative. (a) Applicability. This section applies to the...

  18. Reduction of Cr(VI) to Cr(III) by wetland plants: Potential for in situ heavy metal detoxification

    SciTech Connect

    Lytle, C.M.; Qian, J.H.; Hansen, D.; Zayed, A.; Terry, N.; Lytle, F.W.; Yang, N.

    1998-10-15

    Reduction of heavy metals in situ by plants may be a useful detoxification mechanism for phytoremediation. Using X-ray spectroscopy, the authors show that Eichhornia crassipes (water hyacinth), supplied with Cr(VI) in nutrient culture, accumulated nontoxic Cr(III) in root and shoot tissues. The reduction of Cr(VI) to Cr(III) appeared to occur in the fine lateral roots. The Cr(III) was subsequently translocated to leaf tissues. Extended X-ray absorption fine structure of Cr in leaf and petiole differed when compared to Cr in roots. In roots, Cr(III) was hydrated by water, but in petiole and more so in leaf, a portion of the Cr(III) may be bound to oxalate ligands. This suggests that E. crassipes detoxified Cr(VI) upon root uptake and transported a portion of the detoxified Cr to leaf tissues. Cr-rich crystalline structures were observed on the leaf surface. The chemical species of Cr in other plants, collected from wetlands that contained Cr(VI)-contaminated wastewater, was also found to be Cr(III). The authors propose that this plant-based reduction of Cr(VI) by E. crassipes has the potential to be used for the in situ detoxification of Cr(VI)-contaminated wastestreams.

  19. Reduction of the cytosolic fructose-1,6-bisphosphatase in transgenic potato plants limits photosynthetic sucrose biosynthesis with no impact on plant growth and tuber yield.

    PubMed

    Zrenner, R; Krause, K P; Apel, P; Sonnewald, U

    1996-05-01

    Sucrose produced in source leaves is the predominant carbon source for developing sink tissues in most higher plants. Consequently the rate of sucrose synthesis is likely to be important for sink development and final crop yield. Two sucrose biosynthetic enzymes are believed to possess regulatory properties with respect to the rate of sucrose synthesis: (i) cytosolic FBPase and (ii) sucrose phosphate synthase. To study the impact of reduced photosynthetic sucrose biosynthesis on plant growth and crop yield a cDNA clone encoding cytosolic FBPase was isolated from a potato leaf cDNA library and used for antisense experiments in transgenic potato plants. The cDNA clone cy-F1, containing an open reading frame of 1020 bp highly homologous (85%) to other known sequences of plant cytosolic FBPases, was cloned in reversed orientation between the 35S CaMV promoter and the octopine synthase polyadenylation signal. Out of 75 independent transformants five transgenic lines having 9 to 55% of the wild-type FBPase activity were chosen for further analysis. A 45% reduction of the cytosolic FBPase activity did not cause any measurable change in metabolite concentrations, growth behaviour or photosynthetic parameters of the transgenic plants. Inhibition of cytosolic FBPase activity below 20% of the wild-type activity led to an accumulation of 3-PGA, triose-phosphates and fructose-1,6-biphosphate in source leaves. This resulted in a reduced light-saturated rate of assimilation measured via gas exchange and a decreased photosynthetic rate under conditions of the leaf disc electrode with saturating light and CO2. Measuring photosynthetic carbon fluxes by labelling leaf discs with 14CO2 revealed a 53-65% reduction of sucrose synthesis whereas starch synthesis decreased only by 18-24%. The flux into the anionic and cationic fraction was not altered. Despite these changes steady-state sucrose concentrations were not effected in source leaves from transgenic plants. Starch accumulated by

  20. Experimental Study of the Morphology and Dynamics of Gas-Laden Layers Under the Anodes in an Air-Water Model of Aluminum Reduction Cells

    NASA Astrophysics Data System (ADS)

    Vékony, Klára; Kiss, László I.

    2012-10-01

    The bubble layer formed under an anode and the bubble-induced flow play a significant role in the aluminum electrolysis process. The bubbles covering the anode bottom reduce the efficient surface that can carry current. In our experiments, we filmed and studied the bubble layer under the anode in a real-size air-water electrolysis cell model. Three different flow regimes were found depending on the gas generation rate. The covering factor was found to be proportional to the gas generation rate and inversely proportional to the angle of inclination. A correlation between the average height of the entire bubble layer and the position under the anode was determined. From this correlation and the measured contact sizes, the volume of the accumulated gas was calculated. The sweeping effect of large bubbles was observed. Moreover, the small bubbles under the inner edge of the anode were observed to move backward as a result of the escape of huge gas pockets, which means large momentum transport occurs in the bath.

  1. Evaluation of antioxidant potential and reduction capacity of some plant extracts in silver nanoparticles' synthesis

    PubMed Central

    Goodarzi, Vahid; Zamani, Hajar; Bajuli, Leila; Moradshahi, Ali

    2014-01-01

    The green synthesis of metallic nanoparticles is an active research area in nanotechnology. In the present study, antioxidant potential, total reducing capacity and silver nanoparticles' (Ag NPs) synthetic potential of methanolic leaf extracts of seven plant species were evaluated and compared. Antioxidant capacity, expressed as µmol Trolox equivalents g-1 DW (µmol TE g-1 DW), ranged from 116.0 to 1.80. The plants Rosmarinus sp. and Zataria Multiflora showed highest antioxidant capacities with IC50 of 1.07 and 1.22 mg ml-1, respectively. Total reducing capacity ranged from 7.6 to 0.17 mg gallic acid equivalent to g-1 DW (mg GAE g-1 DW). Plants with high antioxidant potentials also showed higher total reducing capacity. In fact, the order of the plants' reducing capacity was similar to that of their antioxidant potential. The same two plant species, i.e., Zataria Multiflora and Rosmarinus sp, with high reducing capacities, showed higher potentials for Ag NPs synthesis. It is concluded that reducing substances in the extracts contribute significantly to the antioxidant potential of the tested plant species, and plants with a high reducing capacity are excellent sources for the green synthesis of metallic nanoparticles. In addition, synthetic antioxidants have adverse effects on human health; therefore, to benefit more from the health promoting properties of plant species, evaluating their novel natural antioxidants is recommended. PMID:27843980

  2. Invasive and native plant responses to shrubland fuel reduction: comparing prescribed fire, mastication, and treatment season

    Treesearch

    Jennifer B. Potts; Scott L. Stephens

    2009-01-01

    Fuel reduction in the wildland–urban interface is a widely used international strategy for assisting human communities regarding wildfire threats, but very little research has examined whether certain fuel reduction methods and their seasonal timing promote nonnative invasion. To...

  3. Design for aluminum recycling

    SciTech Connect

    Not Available

    1993-10-01

    This article describes the increasing use of aluminum in automobiles and the need to recycle to benefit further growth of aluminum applications by assuring an economical, high-quality source of metal. The article emphasizes that coordination of material specifications among designers can raise aluminum scrap value and facilitate recycling. Applications of aluminum in automobile construction are discussed.

  4. Effects of aluminum on the reduction of neural stem cells, proliferating cells, and differentiating neuroblasts in the dentate gyrus of D-galactose-treated mice via increasing oxidative stress

    PubMed Central

    Nam, Sung Min; Kim, Jong Whi; Yoo, Dae Young; Kim, Woosuk; Jung, Hyo Young; Choi, Jung Hoon; Hwang, In Koo; Seong, Je Kyung

    2016-01-01

    Aluminum (Al) accumulation increases with aging, and long-term exposure to Al is regarded as a risk factor for Alzheimer's disease. In this study, we investigated the effects of Al and/or D-galactose on neural stem cells, proliferating cells, differentiating neuroblasts, and mature neurons in the hippocampal dentate gyrus. AlCl3 (40 mg/kg/day) was intraperitoneally administered to C57BL/6J mice for 4 weeks. In addition, vehicle (physiological saline) or D-galactose (100 mg/kg) was subcutaneously injected to these mice immediately after AlCl3 treatment. Neural stem cells, proliferating cells, differentiating neuroblasts, and mature neurons were detected using the relevant marker for each cell type, including nestin, Ki67, doublecortin, and NeuN, respectively, via immunohistochemistry. Subchronic (4 weeks) exposure to Al in mice reduced neural stem cells, proliferating cells, and differentiating neuroblasts without causing any changes to mature neurons. This Al-induced reduction effect was exacerbated in D-galactose-treated mice compared to vehicle-treated adult mice. Moreover, exposure to Al enhanced lipid peroxidation in the hippocampus and expression of antioxidants such as Cu, Zn- and Mn-superoxide dismutase in D-galactose-treated mice. These results suggest that Al accelerates the reduction of neural stem cells, proliferating cells, and differentiating neuroblasts in D-galactose-treated mice via oxidative stress, without inducing loss in mature neurons. PMID:26243606

  5. Energy Assessment Helps Kaiser Aluminum Save Energy and Improve Productivity

    SciTech Connect

    2008-07-01

    The Kaiser Aluminum plant in Sherman, Texas, adjusted controls and made repairs to a furnace for a simple payback of 1 month. Kaiser adopted DOE's Process Heating Assessment and Survey Tool (PHAST) software as the corporate diagnostic tool and has used it to evaluate process heating systems at five other aluminum plants.

  6. Chemical synthesis of aluminum nanoparticles

    NASA Astrophysics Data System (ADS)

    Ghanta, Sekher Reddy; Muralidharan, Krishnamurthi

    2013-06-01

    An alternate synthetic route has been described for the production of aluminum nanoparticles (Al-NPs). These Al-NPs were obtained through a reduction of aluminum acetylacetonate [Al(acac)3] by lithium aluminum hydride (LiAlH4) in mestitylene at 165 °C. The side products were removed by repeated washing with dry, ice cold methanol and the reaction mixture was filtered to obtain gray-colored Al-NPs. The synthesized nanoparticles were characterized by Powder X-ray diffraction pattern and 27Al-MAS-NMR spectrum. The X-ray diffraction pattern confirmed the formation of face-centered cubic (fcc) form of aluminum. The size and morphology were investigated by scanning electron microscope and transmission electron microscope which showed particle of varying shapes with size ranging from 50 to 250 nm. The weight loss from the nanoparticles was studied by thermo gravimetric analysis which indicated that the nanoparticles were tightly bound with an unknown amorphous organic residue which cannot be removed by simple washing. The carbonaceous residue might be outcome of the decomposition of acac ligand which was responsible in stabilizing aluminum nanoparticles.

  7. Effect of dissimilatory iron and sulfate reduction on arsenic dynamics in the wetland rhizosphere and its bioaccumulation in plants

    NASA Astrophysics Data System (ADS)

    Jaffe, P. R.; Zhang, Z.; Moon, H. S.; Myneni, S.

    2015-12-01

    The mobility of arsenic in soils is linked to biogeochemical redox processes. The presence of wetland plants in riparian wetlands has a significant impact on the biogeochemical dynamics of the soil/sediment-redoxcline due to the release of root exudates and root turnover and oxygen transfer from the roots into the surrounding sediment. Micro-environmental redox conditions in the rhizosphere affect As, Fe, and S speciation as well as Fe(III) plaque deposition, which affects arsenic transport and uptake by plants. To investigate the dynamics of As coupled to S and Fe cycling in wetlands, mesocosms were operated in a greenhouse under various conditions (high and low Fe, high and low sulfate, with plant and without plants) for four months. Results show that the presence of plants, high Fe, and high SO42- levels enhanced As sequestration in these soils. We hypothesize that this compounding effect is because plants release biodegradable organic carbon, which is used by microorganism to reduce ferrihydrite and SO42- to generate FeS, FeS2, and/or orpiment (As2S3). Over the concentration range studied, As immobilization in soil and uptake by Scirpus actus was mainly controlled by SO42- rather than Fe levels. Under high sulfate levels, As immobilization in soil increased by 50% and As concentrations in plant roots increased by 97%, whereas no significant changes in plant As levels were seen for varying Fe concentrations. More than 80% of As was sequestrated in soils rather than plant uptake. Pore water As speciation analyses indicate that 20% more As(V) was reduced to As(III) under high sulfate as than low sulfate levels and that low Fe was more favorable to the As dissimilatory reduction. More dissimilatory arsenate-respiring bacteria (DARB) under high sulfate were confirmed by quantitative PCR. Arsenic distribution in plant leafs and roots after 30 days of exposure to As was analyzed via Synchrotron X-ray fluorescence analyses. The uptake of As by plants was distributed

  8. Adaptation of U(IV) reductant to Savannah River Plant Purex processes

    SciTech Connect

    Orebaugh, E.G.

    1986-04-01

    Partitioning of uranium and plutonium in the Purex process requires the reduction of the extracted Pu(IV) to the less extractable Pu(III). This valence adjustment at SRP has historically been performed by the addition of ferrous ion, which eventually constitutes a major component of high-level waste solids requiring costly permanent disposal. Uranous nitrate, U(IV), is a kinetically fast reductant which may be substituted for Fe(II) without contributing to waste solids. This report documents U(IV) flowsheet development in the miniature mixer-settler equipment at SRL and provides an insight into the mechanisms responsible for the successful direct substitution of U(IV) for Fe(II) in 1B bank extractant. U(IV) will be the reductant of choice when its fast reduction kinetics are required in centrifugal-contactor-based processing. The flowsheets investigated here should transfer to such equipment with minimal modifications.

  9. Anaerobic side-stream reactor for excess sludge reduction: 5-year management of a full-scale plant.

    PubMed

    Velho, V F; Foladori, P; Andreottola, G; Costa, R H R

    2016-07-15

    The long-term performances of a full-scale anaerobic side-stream reactor (ASSR) aimed at sludge reduction have been monitored for the first time, in comparison with a conventional activated sludge process (CAS). The plant was integrated with an ASSR treatment of 2293-3293 m(3). Operational parameters in the ASSR were: ORP -250 mV, interchange ratio of 7-10%, hydraulic retention time of 7 d. No worsening of effluent quality was observed in the ASSR configuration and removal efficiency of COD and NH4 was above 95%. A slight increase in the Sludge Volume Index did not cause worsening in effluent solids concentration. The observed sludge yield (Yobs) passed from 0.44 kgTSS/kgCOD in the CAS to 0.35 in the ASSR configuration. The reduction of Yobs by 20% is lower than expected from the literature where sythetic wastewater is used, indicating that sludge reduction efficiency is largely affected by inert mass fed with influent real wastewater. An increase by 45% of the ASSR volume did not promote a further reduction of Yobs, because sludge reduction is affected not solely by endogenous decay but also by other factors such as interchange ratio and aerobiosis/anaerobiosis alternation.

  10. Interaction of aluminum projectiles with quartz sand in impact experiments: Formation of khatyrkite (CuAl2) and reduction of SiO2 to Si

    NASA Astrophysics Data System (ADS)

    Hamann, Christopher; Stöffler, Dieter; Reimold, Wolf Uwe

    2016-11-01

    We analyzed the interaction of spherical, 6.36-mm-diameter, Cu-bearing aluminum projectiles with quartz sand targets in hypervelocity impact experiments performed at NASA Ames Vertical Gun Range. Impact velocities and inferred peak shock pressures varied between 5.9 and 6.5 km/s and ∼41 and 48 GPa, respectively. Shocked particles (;impact melt particles;) coated with thin crusts of molten projectile material were recovered from the floors of the ca. 33-cm-diameter craters and the respective ejecta blankets. Through petrographic and chemical (optical microscopy, FE-EMPA, SEM-EDX, and XRF) analysis we show that these particles have a layered structure manifested in distinct layers of decreasing shock metamorphism. These can be characterized by the following physical and chemical reactions and alteration products: (i) complete melting and subsequent recrystallization of the projectile, forming a distinct crystallization texture in the fused metal crust; (ii) projectile-target mixing, involving a redox reaction between Cu-bearing Al alloy und SiO2, leading to formation of khatyrkite (CuAl2), Al2O3 melt, euhedral silicon crystals, and spherical droplets of silicon; (iii) melting of quartz to lechatelierite and formation of planar deformation features in relic quartz grains; and (iv) shock lithification of quartz grains with fracturing of grains, grain-boundary melting, planar deformation features, and complete loss of porosity. To our knowledge, this is the first report of khatyrkite formed experimentally in hypervelocity impact experiments. These results have implications for the understanding of a similar redox reaction between Al-Cu metal and siliceous impact melt recently postulated for the Khatyrka CV3 carbonaceous chondrite. Moreover, these results bear on the processes that lead to layers of regolith on the surfaces of planetary bodies without atmospheres, such as asteroids in the main belt (e.g., 4 Vesta), and on the Moon. Specifically, impacts of mm

  11. The BOS-X approach: achieving drastic cost reduction in CPV through holistic power plant level innovation

    NASA Astrophysics Data System (ADS)

    Plesniak, A.; Garboushian, V.

    2012-10-01

    In 2011, the Amonix Advanced Technology Group was awarded DOE SunShot funding in the amount of 4.5M to design a new Balance of System (BOS) architecture utilizing Amonix MegaModules™ focused on reaching the SunShot goal of 0.06-$0.08/kWhr LCOE. The project proposal presented a comprehensive re-evaluation of the cost components of a utility scale CPV plant and identified critical areas of focus where innovation is needed to achieve cost reduction. As the world's premier manufacturer and most experienced installer of CPV power plants, Amonix is uniquely qualified to lead a rethinking of BOS architecture for CPV. The presentation will focus on the structure of the BOS-X approach, which looks for the next wave of cost reduction in CPV through evaluation of non-module subsystems and the interaction between subsystems during the lifecycle of a solar power plant. Innovation around nonmodule components is minimal to date because CPV companies are just now getting enough practice through completion of large projects to create ideas and tests on how to improve baseline designs and processes. As CPV companies increase their installed capacity, they can utilize an approach similar to the methodology of BOS-X to increase the competitiveness of their product. Through partnership with DOE, this holistic approach is expected to define a path for CPV well aligned with the goals of the SunShot Initiative.

  12. Comparison between ozonation and the OSA process: analysis of excess sludge reduction and biomass activity in two different pilot plants.

    PubMed

    Torregrossa, Michele; Di Bella, Gaetano; Di Trapani, Daniele

    2012-01-01

    The excess biomass produced during biological treatment of municipal wastewater represents a major issue worldwide, as its disposal implies environmental, economic and social impacts. Therefore, there has been a growing interest in developing technologies to reduce sludge production. The main proposed strategies can be categorized according to the place inside the wastewater treatment plant (WWTP) where the reduction takes place. In particular, sludge minimization can be achieved in the wastewater line as well as in the sludge line. This paper presents the results of two pilot scale systems, to evaluate their feasibility for sludge reduction and to understand their effect on biomass activity: (1) a pilot plant with an ozone contactor in the return activated sludge (RAS) stream for the exposition of sludge to a low ozone dosage; and (2) an oxic-settling-anaerobic (OSA) process with high retention time in the anaerobic sludge holding tank have been studied. The results showed that both technologies enabled significant excess sludge reduction but produced a slight decrease of biomass respiratory activity.

  13. Integrated safety assessment of an oxygen reduction project at Connecticut Yankee Atomic Power's Haddam Neck plant

    SciTech Connect

    Aubrey, J.E.

    1987-01-01

    Connecticut Yankee Atomic Power Company (CYAPCo) has implemented an Integrated Safety Assessment Program (ISAP) for the integrated evaluation and prioritization of plant-specific licensing issues, regulatory policy issues, and plant improvement projects. As part of the ISAP process, probabilistic risk assessment (PRA) is utilized to evaluate the net safety impact of plant modification projects. On a few occasions, implementation of this approach has resulted in the identification of projects with negative safety impacts that could not be quantified via the normal design review and 10CFR50.59 safety evaluation process. An example is a plant modification that was proposed to reduce the oxygen in the Haddam Neck plant's demineralized water storage tank (DWST). The project involved the design and installation of a nitrogen blanketing system on the DWST. The purpose of the project was to reduce the oxygen content on the secondary side, consistent with recommendations from the Electric Power Research Institute Steam Generator Owners Group. Oxygen is one of the contributors to the corrosion process in systems in contact with the feedwater and can cause damage to associated components if not controlled.

  14. Klebsiella pneumoniae Planktonic and Biofilm Reduction by Different Plant Extracts: In Vitro Study

    PubMed Central

    da Rocha Santos, Carlos Eduardo; Camargo Reis Mello, Daphne; Nishiama Theodoro, Lígia; De Oliveira, Felipe Eduardo; Back Brito, Graziella N.; Campos Junqueira, Juliana; Cardoso Jorge, Antonio Olavo; Dias de Oliveira, Luciane

    2016-01-01

    This study evaluated the action of Pfaffia paniculata K., Juglans regia L., and Rosmarius officinalis L. extracts against planktonic form and biofilm of Klebsiella pneumoniae (ATCC 4352). Minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) values were determined for each extract by microdilution broth method, according to Clinical and Laboratory Standards Institute. Next, antimicrobial activity of the extracts on biofilm was analyzed. For this, standardized suspension at 107 UFC/mL of K. pneumoniae was distributed into 96-well microplates (n = 10) and after 48 h at 37°C and biofilm was subjected to treatment for 5 min with the extracts at a concentration of 200 mg/mL. ANOVA and Tukey tests (5%) were used to verify statistical significant reduction (p < 0.05) of planktonic form and biofilm. P paniculata K., R. officinalis L., and J. regia L. showed reductions in biomass of 55.6, 58.1, and 18.65% and cell viability reduction of 72.4, 65.1, and 31.5%, respectively. The reduction obtained with P. paniculata and R. officinalis extracts was similar to the reduction obtained with chlorhexidine digluconate 2%. In conclusion, all extracts have microbicidal action on the planktonic form but only P. paniculata K. and R. officinalis L. were effective against biofilm. PMID:28004034

  15. Competitive reduction of perferrylmyoglobin radicals by protein thiols and plant phenols.

    PubMed

    Jongberg, Sisse; Lund, Marianne N; Skibsted, Leif H; Davies, Michael J

    2014-11-19

    Radical transfer from perferrylmyoglobin to other target species (myofibrillar proteins, MPI) and bovine serum albumin (BSA), extracts from green tea (GTE), maté (ME), and rosemary (RE), and three phenolic compounds, catechin, caffeic acid, and carnosic acid) was investigated by electron paramagnetic resonance (EPR) spectroscopy to determine the concentrations of plant extracts required to protect against protein oxidation. Blocking of MPI thiol groups by N-ethylmaleimide was found to reduce the rate of reaction of MPI with perferrylmyoglobin radicals, signifying the importance of protein thiols as radical scavengers. GTE had the highest phenolic content of the three extracts and was most effective as a radical scavenger. IC50 values indicated that the molar ratio between phenols in plant extract and MPI thiols needs to be >15 in order to obtain efficient protection against protein-to-protein radical transfer in meat. Caffeic acid was found most effective among the plant phenols.

  16. Sustainable reduction of bioreactor contamination in an industrial fermentation pilot plant.

    PubMed

    Junker, Beth; Lester, Michael; Leporati, James; Schmitt, John; Kovatch, Michael; Borysewicz, Stan; Maciejak, Waldemar; Seeley, Anna; Hesse, Michelle; Connors, Neal; Brix, Thomas; Creveling, Eric; Salmon, Peter

    2006-10-01

    Facility experience primarily in drug-oriented fermentation equipment (producing small molecules such as secondary metabolites, bioconversions, and enzymes) and, to a lesser extent, in biologics-oriented fermentation equipment (producing large molecules such as recombinant proteins and microbial vaccines) in an industrial fermentation pilot plant over the past 15 years is described. Potential approaches for equipment design and maintenance, operational procedures, validation/verification testing, medium selection, culture purity/sterility analysis, and contamination investigation are presented, and those approaches implemented are identified. Failure data collected for pilot plant operation for nearly 15 years are presented and best practices for documentation and tracking are outlined. This analysis does not exhaustively discuss available design, operational and procedural options; rather it selectively presents what has been determined to be beneficial in an industrial pilot plant setting. Literature references have been incorporated to provide background and context where appropriate.

  17. Reduction of neonicotinoid insecticide residues in Prairie wetlands by common wetland plants.

    PubMed

    Main, Anson R; Fehr, Jessica; Liber, Karsten; Headley, John V; Peru, Kerry M; Morrissey, Christy A

    2017-02-01

    Neonicotinoid insecticides are frequently detected in wetlands during the early to mid-growing period of the Canadian Prairie cropping season. These detections also overlap with the growth of macrophytes that commonly surround agricultural wetlands which we hypothesized may reduce neonicotinoid transport and retention in wetlands. We sampled 20 agricultural wetlands and 11 macrophyte species in central Saskatchewan, Canada, over eight weeks to investigate whether macrophytes were capable of reducing movement of neonicotinoids from cultivated fields and/or reducing concentrations in surface water by accumulating insecticide residues into their tissues. Study wetlands were surrounded by clothianidin-treated canola and selected based on the presence (n=10) or absence (n=10) of a zonal plant community. Neonicotinoids were positively detected in 43% of wetland plants, and quantified in 8% of all plant tissues sampled. Three plant species showed high rates of detection: 78% Equisetum arvense (clothianidin, range: plant height, water depth) on neonicotinoid concentrations in Prairie wetlands over time using linear mixed-effects models. Clothianidin concentrations were significantly lower in wetlands surrounded by taller plants (β±S.E.: -0.57±0.12, P≤0.001). The results of this study suggest that macrophytes can play an important role in mitigating water contamination by accumulating neonicotinoids and possibly slowing transport to wetlands during the growing season.

  18. Reduction in cholesterol absorption is enhanced by stearate-enriched plant sterol esters in hamsters.

    PubMed

    Rasmussen, Heather E; Guderian, David M; Wray, Curtis A; Dussault, Patrick H; Schlegel, Vicki L; Carr, Timothy P

    2006-11-01

    Consumption of plant sterol esters reduces plasma LDL cholesterol concentration by inhibiting intestinal cholesterol absorption. Commercially available plant sterol esters are prepared by esterifying free sterols to fatty acids from edible plant oils such as canola, soybean, and sunflower. To determine the influence of the fatty acid moiety on cholesterol metabolism, plant sterol esters were made with fatty acids from soybean oil (SO), beef tallow (BT), or purified stearic acid (SA) and fed to male hamsters for 4 wk. A control group fed no plant sterol esters was also included. Hamsters fed BT and SA had significantly lower cholesterol absorption and decreased concentrations of plasma non-HDL cholesterol and liver esterified cholesterol, and significantly greater fecal sterol excretion than SO and control hamsters. Cholesterol absorption was lowest in hamsters fed SA (7.5%), whereas it was 72.9% in control hamsters. Cholesterol absorption was correlated with fecal sterol excretion (r = -0.72, P < 0.001), liver cholesterol concentration (r = 0.88, P < 0.001), and plasma non-HDL cholesterol concentration (r = 0.85, P < 0.001). A multiple regression model that included each sterol ester type vs. cholesterol absorption indicated that intake of steryl stearate was the only dietary component that contributed significantly to the model (R2 = -0.75, P < 0.001). Therefore, our results demonstrate that BT and SA are more effective than SO in reducing cholesterol absorption, liver cholesterol, and plasma non-HDL cholesterol concentration, suggesting that cardioprotective benefits can be achieved by consuming stearate-enriched plant sterol esters.

  19. Is sulfur accumulation in sulfur dioxide-exposed plants related to biomass reduction

    SciTech Connect

    Lorenzini, G.; Panicucci, A. )

    1994-06-01

    Sulfur (S) is an abundant element in the Earth's crust. It is a major plant nutrient,necessary in plant metabolism. Normally, S is taken up from soil in the sulphate form and assimilated into various compounds. Sulfur dioxide (SO[sub 2]) absorbed from the air can also supply S for nutrition. Of all plant organs, the leaves have the highest S content. SO[sub 2] is an air contaminant, especially a consequence of burning fossil fuels, as well as having significant natural sources. Plants exposed to excessive SO[sub 2] levels may be associated with visible injury and biomass production perturbation. Two questions may be raised: is S accumulation correlated with other responses, such as resistance or tolerance to SO[sub 2] and can S accumulation be a useful tool for diagnostic purposes when SO[sub 2] is suspected of being responsible for altered plants Unfortunately, these questions are not easily answered. It takes a substantial build-up before any increase is significant. Accumulation may also be influenced by the level of S nutrition. Experiments under controlled conditions are essential. Many experiments performed in the past used rather high SO[sub 2] concentrations and short duration, but the extrapolation to [open quote]natural[close quote] situations is difficult. Results here reported refer to experiments carried out in order to get more information on some aspects of sulphur accumulation in plants under realistic, nonmarking, SO[sub 2] pollution conditions, in connection with biomass production. 18 refs., 1 fig., 3 tabs.

  20. Modelling of the nitric acid reduction process: Application to materials behavior in reprocessing plants

    SciTech Connect

    Sicsic, D.; Balbaud-Celerier, F.; Tribollet, B.

    2012-07-01

    In France, the recycling process of nuclear waste fuels involves the use of hot concentrated nitric acid. The understanding and the prediction of the structural materials (mainly austenitic stainless steels) behaviour requires the determination of the nitric acid reduction process. Nitric acid is indirectly reduced by an autocatalytic mechanism depending on the cathodic overpotential and the acid concentration. This mechanism has been widely studied. All the authors agree on its autocatalytic nature, characterized by the predominant role of the reduction products. It is also generally admitted that nitric acid or the nitrate ion are not the electro-active species. However, uncertainties remain concerning the nature of the electro-active species, the place where the catalytic species regenerates and the thermodynamic and kinetic behaviour of the reaction intermediates. The aim of this study is to clarify some of these uncertainties by performing an electrochemical investigation of the 4 mol.L -1 nitric acid reduction process at 40 deg. C occurring on an inert electrode (platinum or gold). An inert electrode was chosen as a working electrode in a first step in order to avoid its oxidation and focus the research on the reduction mechanism. This experimental work enabled to suggest a coherent sequence of electrochemical and chemical reactions. Then, a kinetic modelling of this sequence was carried out for a gold rotating disk system. In this objective, a thermodynamic study at 25 deg. C led to the evaluation of the composition of liquid and gaseous phases for nitric acid solutions from 0.5 to 22 mol.L -1. The kinetics of the reduction process of nitric acid 4 mol.L -1 was investigated by cyclic voltammetry and chrono-amperometry on an inert electrode at 40 deg. C. A coupling of chrono-amperometry and FTIR in gaseous phase led to the identification of the gaseous reduction products as a function of the cathodic overpotential. These different results showed that for

  1. Mechanisms of Functional and Physical Genome Reduction in Photosynthetic and Nonphotosynthetic Parasitic Plants of the Broomrape Family[W][OPEN

    PubMed Central

    Wicke, Susann; Müller, Kai F.; de Pamphilis, Claude W.; Quandt, Dietmar; Wickett, Norman J.; Zhang, Yan; Renner, Susanne S.; Schneeweiss, Gerald M.

    2013-01-01

    Nonphotosynthetic plants possess strongly reconfigured plastomes attributable to convergent losses of photosynthesis and housekeeping genes, making them excellent systems for studying genome evolution under relaxed selective pressures. We report the complete plastomes of 10 photosynthetic and nonphotosynthetic parasites plus their nonparasitic sister from the broomrape family (Orobanchaceae). By reconstructing the history of gene losses and genome reconfigurations, we find that the establishment of obligate parasitism triggers the relaxation of selective constraints. Partly because of independent losses of one inverted repeat region, Orobanchaceae plastomes vary 3.5-fold in size, with 45 kb in American squawroot (Conopholis americana) representing the smallest plastome reported from land plants. Of the 42 to 74 retained unique genes, only 16 protein genes, 15 tRNAs, and four rRNAs are commonly found. Several holoparasites retain ATP synthase genes with intact open reading frames, suggesting a prolonged function in these plants. The loss of photosynthesis alters the chromosomal architecture in that recombinogenic factors accumulate, fostering large-scale chromosomal rearrangements as functional reduction proceeds. The retention of DNA fragments is strongly influenced by both their proximity to genes under selection and the co-occurrence with those in operons, indicating complex constraints beyond gene function that determine the evolutionary survival time of plastid regions in nonphotosynthetic plants. PMID:24143802

  2. Reduction of CO(2)-emissions by using biomass in combustion and digestion plants.

    PubMed

    Hoffmann, Gaston; Schingnitz, Daniel; Schnapke, Antje; Bilitewski, Bernd

    2010-05-01

    Climate protection is one of the main aims of environmental policy. One way to advance and push the progress is to reduce the use of fossil fuels for energy production through an increasing production of renewable and CO(2)-neutral energy for example through application of biomass. This paper sets the focus on biomass streams that can be used both thermal and biological for energy production like grass or energy crops. To calculate the potentials of decrease of CO(2)-emissions for treatment of biomass in either combustion or digestion plants some scenarios were set up with different assumptions regarding degree of efficiency of treatment plants which depends on size of plants and the treatment process itself. The energetic utilisation of the considered biomass streams is divided in different utilisation scenarios: combined heat and power generation (CHP) and heat generation or power generation only. Additionally four groups of plant sizes referring to electrical power (from 0.1 up to 10.0MW) were taken into consideration. The calculations of potential savings of CO(2)-emission in both types of treatment scenarios lead to the result that in comparison to biological technologies thermal processes show a much higher utilisation of the energy content in biomass.

  3. Formation of tetrahydrocurcumin by reduction of curcumin with cultured plant cells of Marchantia polymorpha.

    PubMed

    Shimoda, Kei; Kubota, Naoji; Hirano, Hirotaka; Matsumoto, Masahiro; Hamada, Hatsuyuki; Hamada, Hiroki

    2012-04-01

    Cultured plant cells of Marchantia polymorpha, Nicotiana tabacum, Phytolacca americana, Catharanthus roseus, and Gossypium hirsutum were examined for their ability to reduce curcumin. Only M. polymorpha cells converted curcumin into tetrahydrocurcumin in 90% yield in one day. Time-course experiment revealed a two-step formation of tetrahydrocurcumin via dihydrocurcumin.

  4. Optimal design of hybrid separation systems for in-plant waste reduction

    SciTech Connect

    Hamad, A.A.; Crabtree, E.W.; El-Halwagi, M.M.; Garrison, G.W.

    1996-12-31

    A general procedure for using hybrid separation systems to prevent pollution is presented. The design procedure integrates segregation, interception, and recycle. A systematic method developed to identify the optimal design combination is illustrated through a case study. The case study presented is the removal of cresol from aqueous wastes in a tricresyl phosphate plant. 21 refs., 4 figs.

  5. Maintenance error reduction strategies in nuclear power plants, using root cause analysis.

    PubMed

    Wu, T M; Hwang, S L

    1989-06-01

    This study proposes a conceptual model of maintenance tasks to facilitate the identification of root causes of human errors in carrying out such tasks in nuclear power plants. Based on this model, an external/internal classification scheme was developed to discover the root causes of human errors. As a consequence, certain policies pertaining to human error prevention or correction were proposed.

  6. Indirect carbon reduction by residential vegetation and planting strategies in Chicago, U.S.A

    Treesearch

    H.K. Jo; E.G. McPherson

    2001-01-01

    Concern about climate change has evoked interest in the potential for urban vegetation to help reduce the levels of atmospheric carbon. This study applied computer simulations to try to quantify the modifying effects of existing vegetation on the indirect reduction of atmospheric carbon for two residential neighborhoods in north-west Chicago. The effects of shading,...

  7. Mathematical optimization techniques for managing selective catalytic reduction for a fleet of coal-fired power plants

    NASA Astrophysics Data System (ADS)

    Alanis Pena, Antonio Alejandro

    Major commercial electricity generation is done by burning fossil fuels out of which coal-fired power plants produce a substantial quantity of electricity worldwide. The United States has large reserves of coal, and it is cheaply available, making it a good choice for the generation of electricity on a large scale. However, one major problem associated with using coal for combustion is that it produces a group of pollutants known as nitrogen oxides (NO x). NOx are strong oxidizers and contribute to ozone formation and respiratory illness. The Environmental Protection Agency (EPA) regulates the quantity of NOx emitted to the atmosphere in the United States. One technique coal-fired power plants use to reduce NOx emissions is Selective Catalytic Reduction (SCR). SCR uses layers of catalyst that need to be added or changed to maintain the required performance. Power plants do add or change catalyst layers during temporary shutdowns, but it is expensive. However, many companies do not have only one power plant, but instead they can have a fleet of coal-fired power plants. A fleet of power plants can use EPA cap and trade programs to have an outlet NOx emission below the allowances for the fleet. For that reason, the main aim of this research is to develop an SCR management mathematical optimization methods that, with a given set of scheduled outages for a fleet of power plants, minimizes the total cost of the entire fleet of power plants and also maintain outlet NO x below the desired target for the entire fleet. We use a multi commodity network flow problem (MCFP) that creates edges that represent all the SCR catalyst layers for each plant. This MCFP is relaxed because it does not consider average daily NOx constraint, and it is solved by a binary integer program. After that, we add the average daily NOx constraint to the model with a schedule elimination constraint (MCFPwSEC). The MCFPwSEC eliminates, one by one, the solutions that do not satisfy the average daily

  8. Aluminum nitrate recrystallization and recovery from liquid extraction raffinates

    SciTech Connect

    Griffith, W.L.; Compere, A.L.; Googin, J.M.; Huxtable, W.P.

    1991-09-01

    The solid sludges resulting form biodenitrification of discarded aluminum nitrate are the largest Y-12 Plant process solid waste. Aluminum nitrate feedstocks also represent a major plant materials cost. The chemical constraints on aluminum nitrate recycle were investigated to determine the feasibility of increasing recycle while maintaining acceptable aluminum nitrate purity. Reported phase behavior of analogous systems, together with bench research, indicated that it would be possible to raise the recycle rate from 35% to between 70 and 90% by successive concentration and recrystallization of the mother liquor. A full scale pilot test successfully confirmed the ability to obtain 70% recycle in existing process equipment.

  9. FLOWSHEET FOR ALUMINUM REMOVAL FROM SLUDGE BATCH 6

    SciTech Connect

    Pike, J; Jeffrey Gillam, J

    2008-12-17

    Samples of Tank 12 sludge slurry show a substantially larger fraction of aluminum than originally identified in sludge batch planning. The Liquid Waste Organization (LWO) plans to formulate Sludge Batch 6 (SB6) with about one half of the sludge slurry in Tank 12 and one half of the sludge slurry in Tank 4. LWO identified aluminum dissolution as a method to mitigate the effect of having about 50% more solids in High Level Waste (HLW) sludge than previously planned. Previous aluminum dissolution performed in a HLW tank in 1982 was performed at approximately 85 C for 5 days and dissolved nearly 80% of the aluminum in the sludge slurry. In 2008, LWO successfully dissolved 64% of the aluminum at approximately 60 C in 46 days with minimal tank modifications and using only slurry pumps as a heat source. This report establishes the technical basis and flowsheet for performing an aluminum removal process in Tank 51 for SB6 that incorporates the lessons learned from previous aluminum dissolution evolutions. For SB6, aluminum dissolution process temperature will be held at a minimum of 65 C for at least 24 days, but as long as practical or until as much as 80% of the aluminum is dissolved. As planned, an aluminum removal process can reduce the aluminum in SB6 from about 84,500 kg to as little as 17,900 kg with a corresponding reduction of total insoluble solids in the batch from 246,000 kg to 131,000 kg. The extent of the reduction may be limited by the time available to maintain Tank 51 at dissolution temperature. The range of dissolution in four weeks based on the known variability in dissolution kinetics can range from 44 to more than 80%. At 44% of the aluminum dissolved, the mass reduction is approximately 1/2 of the mass noted above, i.e., 33,300 kg of aluminum instead of 66,600 kg. Planning to reach 80% of the aluminum dissolved should allow a maximum of 81 days for dissolution and reduce the allowance if test data shows faster kinetics. 47,800 kg of the dissolved

  10. System effects of primary energy reduction connected with operation of the CHP plants

    NASA Astrophysics Data System (ADS)

    Ziębik, Andrzej; Gładysz, Paweł

    2017-06-01

    The paper is devoted to explication of one of the advantages of heat and electricity cogeneration, rarely considered in technical literature. Usually attention is paid to the fact that heat losses of the heat distribution network are less severe in the case of cogeneration of heat in comparison with its separate production. But this conclusion is also true in other cases when the internal consumption of heat is significant. In this paper it has been proved in the case of two examples concerning trigeneration technology with an absorption chiller cooperating with a combined heat and power (CHP) plant and CHP plant integrated with amine post-combustion CO2 processing unit. In both considered cases it might be said that thanks to cogeneration we have to do with less severe consequences of significant demand of heat for internal purposes.

  11. Reduction of NO/sub 2/ to NO by rush and other plants

    SciTech Connect

    Nishimura, H.; Hayamizu, T.; Yanagiawa, Y.

    1986-04-01

    Previously the authors reported that rush carpets used in Japanese houses had the capacity to adsorb ambient NO/sub 2/ and the capacity endured for several years. The fate of adsorbed NO/sub 2/ was investigated in the present report. The outlet gas of a contacting tube packed with test material was monitored with a chemiluminescence analyzer for NO/sub 2/ and NO. Rush, lawn grass, and ginkgo leaves were found to adsorb NO/sub 2/ and to liberate NO. At steady state, the conversion of adsorbed NO/sub 2/ to NO reached 70%. The high conversion meant the reduction of adsorbed NO/sub 2/ by some organic matter. The reducing component was isolated by fractionation and identified as a kind of polysaccharide contained in the free sugar fraction of rush. The reduction rate was highly dependent on humidity, and a relation with clustered water in sugar was suggested. 8 references, 7 figures, 3 tables.

  12. Central Plant Optimization for Waste Energy Reduction (CPOWER). ESTCP Cost and Performance Report

    DTIC Science & Technology

    2016-12-01

    NUMBER 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 6. AUTHOR(S) 7. PERFORMING ORGANIZATION NAME(S) AND...ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER 10. SPONSOR/MONITOR’S ACRONYM(S) 11. SPONSOR/MONITOR’S REPORT NUMBER(S) 9...RESPONSIBLE PERSON 19b. TELEPHONE NUMBER (Include area code) 01/12/2016 Cost and Performance Report January 2014 - December 2016 Central Plant

  13. One-pot synthesis of La0.7Sr0.3MnO3 supported on flower-like CeO2 as electrocatalyst for oxygen reduction reaction in aluminum-air batteries

    NASA Astrophysics Data System (ADS)

    Xue, Yejian; Huang, Heran; Miao, He; Sun, Shanshan; Wang, Qin; Li, Shihua; Liu, Zhaoping

    2017-08-01

    A novel La0.7Sr0.3MnO3-CeO2 (LSM-CeO2) hybrid catalyst for oxygen reduction reaction (ORR) has been synthesized by a facile one-pot method. The flower-like CeO2 with the diameter of about 3 μm is formed by the agglomeration of nanosheets with the thickness of about 40 nm. The LSM particles with the diameter of about 150 nm are well distributed on the flower-like CeO2, thus the interaction between LSM and CeO2 is built. Therefore, the LSM-CeO2 composite catalyst exhibits the much higher catalytic activity toward ORR with the direct four-electron transfer mechanism in alkaline solution than LSM or CeO2. Furthermore, the stability of LSM-CeO2 is superior to that of Pt/C, and the current retention is 93% after 100000 s. The maximum power density of the aluminum-air battery using LSM-CeO2 as the ORRC can reach 238 mW cm-2, which is about 29% higher than that with LSM (184 mW cm-2). It indicates that LSM-CeO2 composite material is a promising cathodic electrocatalyst for metal-air batteries.

  14. Reduction of Legionella spp. in Water and in Soil by a Citrus Plant Extract Vapor

    PubMed Central

    Kurzbach, Elena; Score, Jodie; Tejpal, Jyoti; Chi Tangyie, George; Phillips, Carol

    2014-01-01

    Legionnaires' disease is a severe form of pneumonia caused by Legionella spp., organisms often isolated from environmental sources, including soil and water. Legionella spp. are capable of replicating intracellularly within free-living protozoa, and once this has occurred, Legionella is particularly resistant to disinfectants. Citrus essential oil (EO) vapors are effective antimicrobials against a range of microorganisms, with reductions of 5 log cells ml−1 on a variety of surfaces. The aim of this investigation was to assess the efficacy of a citrus EO vapor against Legionella spp. in water and in soil systems. Reductions of viable cells of Legionella pneumophila, Legionella longbeachae, Legionella bozemanii, and an intra-amoebal culture of Legionella pneumophila (water system only) were assessed in soil and in water after exposure to a citrus EO vapor at concentrations ranging from 3.75 mg/liter air to 15g/liter air. Antimicrobial efficacy via different delivery systems (passive and active sintering of the vapor) was determined in water, and gas chromatography-mass spectrometry (GC-MS) analysis of the antimicrobial components (linalool, citral, and β-pinene) was conducted. There was up to a 5-log cells ml−1 reduction in Legionella spp. in soil after exposure to the citrus EO vapors (15 mg/liter air). The most susceptible strain in water was L. pneumophila, with a 4-log cells ml−1 reduction after 24 h via sintering (15 g/liter air). Sintering the vapor through water increased the presence of the antimicrobial components, with a 61% increase of linalool. Therefore, the appropriate method of delivery of an antimicrobial citrus EO vapor may go some way in controlling Legionella spp. from environmental sources. PMID:25063652

  15. Hexavalent chromium reduction potential of Cellulosimicrobium sp. isolated from common effluent treatment plant of tannery industries.

    PubMed

    Bharagava, Ram Naresh; Mishra, Sandhya

    2017-08-22

    Present study deals with the isolation and characterization of a bacterium capable for the effective reduction of Cr(VI) from tannery wastewater. Based on the 16S rRNA gene sequence analysis, this bacterium was identified as Cellulosimicrobium sp. (KX710177). During the Cr(VI) reduction experiment performed at 50, 100, 200,and 300mg/L of Cr(VI) concentrations, the bacterium showed 99.33% and 96.98% reduction at 50 and 100mg/L at 24 and 96h, respectively. However, at 200 and 300mg/L concentration of Cr(VI), only 84.62% and 62.28% reduction was achieved after 96h, respectively. The SEM analysis revealed that bacterial cells exposed to Cr(VI) showed increased cell size in comparison to unexposed cells, which might be due to either the precipitation or adsorption of reduced Cr(III) on bacterial cells. Further, the Energy Dispersive X-ray (EDX) analysis showed some chromium peaks for cells exposed to Cr(VI), which might be either due to the presence of precipitated reduced Cr(III) on cells or complexation of Cr(III) with cell surface molecules. The bacterium also showed resistance and sensitivity against the tested antibiotics with a wide range of MIC values ranging from 250 to 800mg/L for different heavy metals. Thus, this multi-drug and multi-metal resistant bacterium can be used as a potential agent for the effective bioremediation of metal contaminated sites. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. Reduction of Legionella spp. in water and in soil by a citrus plant extract vapor.

    PubMed

    Laird, Katie; Kurzbach, Elena; Score, Jodie; Tejpal, Jyoti; Chi Tangyie, George; Phillips, Carol

    2014-10-01

    Legionnaires' disease is a severe form of pneumonia caused by Legionella spp., organisms often isolated from environmental sources, including soil and water. Legionella spp. are capable of replicating intracellularly within free-living protozoa, and once this has occurred, Legionella is particularly resistant to disinfectants. Citrus essential oil (EO) vapors are effective antimicrobials against a range of microorganisms, with reductions of 5 log cells ml(-1) on a variety of surfaces. The aim of this investigation was to assess the efficacy of a citrus EO vapor against Legionella spp. in water and in soil systems. Reductions of viable cells of Legionella pneumophila, Legionella longbeachae, Legionella bozemanii, and an intra-amoebal culture of Legionella pneumophila (water system only) were assessed in soil and in water after exposure to a citrus EO vapor at concentrations ranging from 3.75 mg/liter air to 15g/liter air. Antimicrobial efficacy via different delivery systems (passive and active sintering of the vapor) was determined in water, and gas chromatography-mass spectrometry (GC-MS) analysis of the antimicrobial components (linalool, citral, and β-pinene) was conducted. There was up to a 5-log cells ml(-1) reduction in Legionella spp. in soil after exposure to the citrus EO vapors (15 mg/liter air). The most susceptible strain in water was L. pneumophila, with a 4-log cells ml(-1) reduction after 24 h via sintering (15 g/liter air). Sintering the vapor through water increased the presence of the antimicrobial components, with a 61% increase of linalool. Therefore, the appropriate method of delivery of an antimicrobial citrus EO vapor may go some way in controlling Legionella spp. from environmental sources.

  17. Drought Stress Causes a Reduction in the Biosynthesis of Ascorbic Acid in Soybean Plants

    PubMed Central

    Seminario, Amaia; Song, Li; Zulet, Amaia; Nguyen, Henry T.; González, Esther M.; Larrainzar, Estíbaliz

    2017-01-01

    Drought provokes a number of physiological changes in plants including oxidative damage. Ascorbic acid (AsA), also known as vitamin C, is one of the most abundant water-soluble antioxidant compound present in plant tissues. However, little is known on the regulation of AsA biosynthesis under drought stress conditions. In the current work we analyze the effects of water deficit on the biosynthesis of AsA by measuring its content, in vivo biosynthesis and the expression level of genes in the Smirnoff-Wheeler pathway in one of the major legume crop, soybean (Glycine max L. Merr). Since the pathway has not been described in legumes, we first searched for the putative orthologous genes in the soybean genome. We observed a significant genetic redundancy, with multiple genes encoding each step in the pathway. Based on RNA-seq analysis, expression of the complete pathway was detected not only in leaves but also in root tissue. Putative paralogous genes presented differential expression patterns in response to drought, suggesting the existence of functional specialization mechanisms. We found a correlation between the levels of AsA and GalLDH biosynthetic rates in leaves of drought-stressed soybean plants. However, the levels of GalLDH transcripts did not show significant differences under water deficit conditions. Among the other known regulators of the pathway, only the expression of VTC1 genes correlated with the observed decline in AsA in leaves. PMID:28663755

  18. Satellite-Observed US Power Plant NOx Emission Reductions and Their Impact on Air Quality

    NASA Astrophysics Data System (ADS)

    Kim, S.; Heckel, A.; McKeen, S.; Frost, G.; Hsie, E.; Trainer, M.; Richter, A.; Burrows, J.; Peckham, S.; Grell, G.

    2005-05-01

    Nitrogen oxide (NOx) emissions resulting from fossil fuel combustion lead to unhealthy levels of near-surface ozone (O3). O3 exceedances in the northeast US have been associated with NOx emissions from point sources, especially coal-burning power plants. As a result, numerous programs to control point source NOx emissions in the eastern US have been implemented over the past decade. Here we assess the change of regional NOx emissions in the eastern US by comparing nitrogen dioxide (NO2) columns derived from the satellite instruments with three-dimensional regional scale chemical transport model results that include the estimated NOx emission changes. SCIAMACHY measurements are used in comparisons with WRF-Chem model simulations for 2004 because of their availability and similar horizontal resolution to the model simulations. However, to get the long term evolution of NO2 columns between 1997 and 2005, both GOME and SCIAMACHY data are utilized. Satellite observations clearly detect both year-to-year and summertime NO2 column decreases in regions impacted by power plants that have implemented NOx controls over the past decade. In the Ohio River Valley, where power plants dominate NOx emission, satellite-retrieved summertime NO2 columns and bottom-up emission estimates show larger decreases than in the northeast US urban corridor.

  19. Satellite-Observed US Power Plant NOx Emission Reductions and Their Impact on Air Quality

    NASA Astrophysics Data System (ADS)

    Kim, S.; Heckel, A.; McKeen, S.; Frost, G.; Hsie, E.; Trainer, M.; Richter, A.; Burrows, J.; Peckham, S.; Grell, G.

    2006-12-01

    Nitrogen oxide (NOx) emissions resulting from fossil fuel combustion lead to unhealthy levels of near-surface ozone (O3). O3 exceedances in the northeast US have been associated with NOx emissions from point sources, especially coal-burning power plants. As a result, numerous programs to control point source NOx emissions in the eastern US have been implemented over the past decade. Here we assess the change of regional NOx emissions in the eastern US by comparing nitrogen dioxide (NO2) columns derived from the satellite instruments with three-dimensional regional scale chemical transport model results that include the estimated NOx emission changes. SCIAMACHY measurements are used in comparisons with WRF-Chem model simulations for 2004 because of their availability and similar horizontal resolution to the model simulations. However, to get the long term evolution of NO2 columns between 1997 and 2005, both GOME and SCIAMACHY data are utilized. Satellite observations clearly detect both year-to-year and summertime NO2 column decreases in regions impacted by power plants that have implemented NOx controls over the past decade. In the Ohio River Valley, where power plants dominate NOx emission, satellite-retrieved summertime NO2 columns and bottom-up emission estimates show larger decreases than in the northeast US urban corridor.

  20. [Reduction of hyperspectral dimensions and construction of discriminating models for identifying wetland plant species].

    PubMed

    Liu, Xue-hua; Sun, Yan; Wu, Yan

    2012-02-01

    The present paper researched and analyzed the hyperspectral data of wetland plant species often occurred in Beijing. The methods of Mahalanobis Distance (MD) and principal component analysis (PCA) were mainly applied to reduce the dimensions of hyperspectral data and to analyze and extract the features of spectra. The authors use the extracted spectra to build identification models for identifying the wetland species. The authors then compared and evaluated the precisions of models and finally obtained the best discriminating model. The results showed that (1) the dimensions of hyperspectral data can be efficiently reduced by both MD and PCA methods. (2) The discriminating models established using the parameters extracted from the resulting spectra of MD and PCA could identify the wetland plants with high precisions of more than 90%. As a result, the conversion and usage of the hyperspectral data can help better understand and well extract the spectra of different wetland plants. Furthermore, the constructed discriminating models for wetland species could also be used in the future to guide us in mapping and monitoring of wetland ecosystem by applying the remote sensing data.

  1. Basic properties of steel plant dust and technological properties of direct reduction

    NASA Astrophysics Data System (ADS)

    She, Xue-Feng; Wang, Jing-Song; Xue, Qing-Guo; Ding, Yin-Gui; Zhang, Sheng-Sheng; Dong, Jie-Ji; Zeng, Hui

    2011-06-01

    Basic physicochemical properties of the dust from Laiwu Iron and Steel Co. Ltd. were studied. It is found that C, Zn, K, Na, etc. exist in the fabric filter dust, off gas (OG) sludge, fine ash in converter, and electrical field dust in sinter. Among these, OG sludge gives the finest particle, more than 90% of which is less than 2.51 μm. The dust can lead to a serious negative influence on the production of sintering and blast furnaces (BF) if it is recycled in sintering. The briquette and reduction experimental results showed that the qualified strength could be obtained in the case of 8wt% molasses or 4wt% QT-10 added as binders. Also, more than 75% of metallization ratio, more than 95% of dezincing ratio, as well as more than 80% of K and Na removal rates were achieved for the briquettes kept at 1250°C for 15 min during the direct reduction process. SEM observation indicated that the rates of indirect reduction and carbonization became dominating when the briquettes were kept at 1250°C for 6 min.

  2. Comparative evaluation of five plant extracts and juices for nanoiron synthesis and application for hexavalent chromium reduction.

    PubMed

    Mystrioti, C; Xanthopoulou, T D; Tsakiridis, P; Papassiopi, N; Xenidis, A

    2016-01-01

    The effectiveness of five plant extracts and juices, i.e. extracts of Camellia sinensis (green tea, GT), Syzygium aromaticum (clove, CL), Mentha spicata (spearmint, SM), Punica granatum juice (pomegranate, PG) and Red Wine (RW), for the production of nanoiron suspensions and their application for Cr(VI) reduction was investigated. Polyphenols contained in extracts act as reducing agents for iron ions in aqueous solutions, forming thus iron nanoparticles, and stabilize the nanoparticles produced from further oxidation and agglomeration. The maximum amount of polyphenols extracted per g of herbs was obtained at herb mass to water volume ratio varying from 10 to 20g/L. Suspensions of nanoparticles with sizes below 60nm were produced by mixing iron chloride solution with the plant extracts and juices investigated. The maximum concentration of nanoiron in suspensions was estimated to 22mM, obtained using RW and PG at a mixing ratio of iron solution to extract equal to 2. Lower concentrations, up to 18mM, were achieved using GT and CL extracts. Therefore, PG juice and RW were considered as more effective for nanoiron production, and, together with GT extracts, they were selected for the production of nanoiron suspensions, which have been proven effective for Cr(VI) reduction, reaching removal capacity as high as 500mg Cr(VI) per g of iron in nanoparticles. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Plant Thioredoxin CDSP32 Regenerates 1-Cys Methionine Sulfoxide Reductase B Activity through the Direct Reduction of Sulfenic Acid*

    PubMed Central

    Tarrago, Lionel; Laugier, Edith; Zaffagnini, Mirko; Marchand, Christophe H.; Le Maréchal, Pierre; Lemaire, Stéphane D.; Rey, Pascal

    2010-01-01

    Thioredoxins (Trxs) are ubiquitous enzymes catalyzing the reduction of disulfide bonds, thanks to a CXXC active site. Among their substrates, 2-Cys methionine sulfoxide reductases B (2-Cys MSRBs) reduce the R diastereoisomer of methionine sulfoxide (MetSO) and possess two redox-active Cys as follows: a catalytic Cys reducing MetSO and a resolving one, involved in disulfide bridge formation. The other MSRB type, 1-Cys MSRBs, possesses only the catalytic Cys, and their regeneration mechanisms by Trxs remain unclear. The plant plastidial Trx CDSP32 is able to provide 1-Cys MSRB with electrons. CDSP32 includes two Trx modules with one potential active site 219CGPC222 and three extra Cys. Here, we investigated the redox properties of recombinant Arabidopsis CDSP32 and delineated the biochemical mechanisms of MSRB regeneration by CDSP32. Free thiol titration and 4-acetamido-4′-maleimidyldistilbene-2,2′-disulfonic acid alkylation assays indicated that the Trx possesses only two redox-active Cys, very likely the Cys219 and Cys222. Protein electrophoresis analyses coupled to mass spectrometry revealed that CDSP32 forms a heterodimeric complex with MSRB1 via reduction of the sulfenic acid formed on MSRB1 catalytic Cys after MetSO reduction. MSR activity assays using variable CDSP32 amounts revealed that MSRB1 reduction proceeds with a 1:1 stoichiometry, and redox titrations indicated that CDSP32 and MSRB1 possess midpoints potentials of −337 and −328 mV at pH 7.9, respectively, indicating that regeneration of MSRB1 activity by the Trx through sulfenic acid reduction is thermodynamically feasible in physiological conditions. PMID:20236937

  4. Validation of smart sensor technologies for instrument calibration reduction in nuclear power plants

    SciTech Connect

    Hashemian, H M; Mitchell, D W; Petersen, K M; Shell, C S

    1993-01-01

    This report presents the preliminary results of a research and development project on the validation of new techniques for on-line testing of calibration drift of process instrumentation channels in nuclear power plants. These techniques generally involve a computer-based data acquisition and data analysis system to trend the output of a large number of instrument channels and identify the channels that have drifted out of tolerance. This helps limit the calibration effort to those channels which need the calibration, as opposed to the current nuclear industry practice of calibrating essentially all the safety-related instrument channels at every refueling outage.

  5. Corrosion of aluminum and aluminum alloys

    SciTech Connect

    Davis, J.R.

    1999-01-01

    This new handbook presents comprehensive coverage of the corrosion behavior of aluminum and aluminum alloys, with emphasis on practical information about how to select and process these materials in order to prevent corrosion attack. Described are the characteristics of these materials and the influences of composition, mechanical working, heat treatment, joining methods, microstructure, and environmental variables on their corrosion.

  6. Aluminum extraction from aluminum industrial wastes

    NASA Astrophysics Data System (ADS)

    Amer, A. M.

    2010-05-01

    Aluminum dross tailings, an industrial waste from the Egyptian Aluminum Company (Egyptalum), was used to produce two types of alums: aluminum sulfate alum (Al2(SO4)3·12H2O) and ammonium aluminum alum {(NH4)2SO4AL2 (SO4)3·24H2O}. This was carried out in two processes. The first involves leaching the impurities using diluted H2SO4 with different solid/liquid ratios at different temperatures to dissolve the impurities present in the starting material in the form of aluminum sulfates. The second process is the extraction of aluminum (as aluminum sulfate) from the purified aluminum dross tailings thus produced. This was carried out in an autoclave. The effects of temperature, time of reaction, and acid concentration on pressure leaching and extraction processes were studied in order to specify the optimum conditions to be applied in the bench scale production as well as the kinetics of leaching process.

  7. ALUMINUM-CONTAINING POLYMERS

    DTIC Science & Technology

    ALUMINUM COMPOUNDS, *ORGANOMETALLIC COMPOUNDS, *POLYMERIZATION, *POLYMERS, ACRYLIC RESINS, ALKYL RADICALS, CARBOXYLIC ACIDS, COPOLYMERIZATION, LIGHT TRANSMISSION, STABILITY, STYRENES, TRANSPARENT PANELS.

  8. Reduction of sediment micro-pollution by means of a pilot plant.

    PubMed

    Petavy, F; Ruban, V; Conil, P; Viau, J Y

    2008-01-01

    Solutions need to be found to manage polluted (organic matter, trace elements, hydrocarbons and PAHs) stormwater sediments while complying with stringent economic and environmental requirements. The cost of transport is a relatively large part of the treatment cost for such sediments, hence the development of a pilot unit that could provide their in situ treatment. Seven stormwater sediments were treated by means of the ATTRISED pilot plant, based on sieving and attrition. The objective is to apply a treatment procedure by which as much clean material as possible is recovered, while the pollutants are concentrated in a small volume ready for final destruction or isolation from the environment. Application of the attrition process serves to remove fine particles and contaminants from the surface of sediments and hydrocyclone separations allow to isolate fine contaminated particles (< 60 microm). The results show that particle size separations coupled to an attrition step allow decontamination efficiencies of 76% and 70% for street sweeping and pond sediments, respectively. Although the experiments were carried out on stormwater sediments, all kinds of sediments may be treated by the ATTRISED pilot plant if the mean particle size is greater than 60 microm.

  9. Occurrence and reductions of pharmaceuticals and personal care products and estrogens by municipal wastewater treatment plants in Ontario, Canada.

    PubMed

    Lishman, Lori; Smyth, Shirley Anne; Sarafin, Kurtis; Kleywegt, Sonya; Toito, John; Peart, Thomas; Lee, Bill; Servos, Mark; Beland, Michel; Seto, Peter

    2006-08-31

    Over the last ten years there have been reports of pharmaceuticals and personal care product (PPCP) residuals in municipal wastewater treatment plant (WWTP) effluents. The principle goal of this study was specifically to expand and in some cases establish a Canadian database for the presence of selected acidic drugs, triclosan, polycyclic musks, and selected estrogens in MWWTP influent and effluent. The impact of treatment configuration (e.g. lagoons, conventional activated sludge (CAS), and CAS followed by media filtration (CAS+filtration)) was also examined. For CAS systems, the most prevalent treatment type, the effect of operating temperature and SRT was evaluated. Selected PPCPs included ten acidic pharmaceuticals (i.e. a group of pharmaceuticals that are extractable at a pH of 2 or less), triclosan, five polycyclic musks and two estrogens. The pharmaceuticals and musks were selected on the basis of levels of use in Canada; reported aquatic toxicity effects; and the ability to analyze for the compounds at low levels. Twelve MWWTPs discharging into the Thames River, the second largest river in southwestern Ontario, were surveyed. The only common characteristic of acidic drugs is their extraction pH as they differ in their intended biological function and chemical structure. Many organics degraded by WWTP processes benefit from warm temperatures and long SRTs so the impact of these variables warranted additional attention. Influent concentrations and reductions for acidic drugs reported by this study were compared to other Canadian studies, when available, and European investigations. The data of this study seems consistent with other reports. Ten acidic drugs were considered by this study. Three were consistently present at non-quantifiable levels (e.g. CLF, FNP and FNF). Additionally, one analyte, SYL, presented results that were so inconsistent that the values were not analysed. The remaining six acidic pharmaceuticals were placed into three categories. IBU

  10. Aluminum and Young Artists.

    ERIC Educational Resources Information Center

    Anderson, Thomas

    1980-01-01

    The author suggests a variety of ways in which aluminum and aluminum foil can be used in elementary and junior high art classes: relief drawing and rubbing; printing; repousse; sculpture; mobiles; foil sculpture; and three dimensional design. Sources of aluminum supplies are suggested. (SJL)

  11. Aluminum and Young Artists.

    ERIC Educational Resources Information Center

    Anderson, Thomas

    1980-01-01

    The author suggests a variety of ways in which aluminum and aluminum foil can be used in elementary and junior high art classes: relief drawing and rubbing; printing; repousse; sculpture; mobiles; foil sculpture; and three dimensional design. Sources of aluminum supplies are suggested. (SJL)

  12. Glutathionylation and Reduction of Methacrolein in Tomato Plants Account for Its Absorption from the Vapor Phase1[OPEN

    PubMed Central

    Muramoto, Shoko; Matsubara, Yayoi; Mwenda, Cynthia Mugo; Koeduka, Takao; Sakami, Takuya; Tani, Akira; Matsui, Kenji

    2015-01-01

    A large portion of the volatile organic compounds emitted by plants are oxygenated to yield reactive carbonyl species, which have a big impact on atmospheric chemistry. Deposition to vegetation driven by the absorption of reactive carbonyl species into plants plays a major role in cleansing the atmosphere, but the mechanisms supporting this absorption have been little examined. Here, we performed model experiments using methacrolein (MACR), one of the major reactive carbonyl species formed from isoprene, and tomato (Solanum lycopersicum) plants. Tomato shoots enclosed in a jar with MACR vapor efficiently absorbed MACR. The absorption efficiency was much higher than expected from the gas/liquid partition coefficient of MACR, indicating that MACR was likely metabolized in leaf tissues. Isobutyraldehyde, isobutyl alcohol, and methallyl alcohol (MAA) were detected in the headspace and inside tomato tissues treated with MACR vapor, suggesting that MACR was enzymatically reduced. Glutathione (GSH) conjugates of MACR (MACR-GSH) and MAA (MAA-GSH) were also detected. MACR-GSH was essentially formed through spontaneous conjugation between endogenous GSH and exogenous MACR, and reduction of MACR-GSH to MAA-GSH was likely catalyzed by an NADPH-dependent enzyme in tomato leaves. Glutathionylation was the metabolic pathway most responsible for the absorption of MACR, but when the amount of MACR exceeded the available GSH, MACR that accumulated reduced photosynthetic capacity. In an experiment simulating the natural environment using gas flow, MACR-GSH and MAA-GSH accumulation accounted for 30% to 40% of the MACR supplied. These results suggest that MACR metabolism, especially spontaneous glutathionylation, is an essential factor supporting MACR absorption from the atmosphere by tomato plants. PMID:26169680

  13. Superplasticity in Thermomechanically Processed High Magnesium Aluminum-Magnesium Alloys.

    DTIC Science & Technology

    1984-03-01

    California DTIC EECTE JL I 1984 THESIS SUPERPLASTICITY IN THERMOMECHANICALLY PROCESSED HIGH MAGNESIUM ALUMINUM-MAGNESIUM ALLOYS C:L by CD) John J. Becker...High Magnesium Aluminum- March 1984 Magnesium Alloys S. PERFORMING ORG. REPORT NUMBER 7. AUTHOR(@) S. CONTRACT OR GRANT NUMBER(&) John J. Becker 9...magnesium, aluminum-magnesium alloys were investigated. The thermomechanical processing itself included warm rolling at 300°C to 94% reduction

  14. High temperature corrosion of austenitic stainless steel coils in a direct reduction plant in Mexico

    SciTech Connect

    Juarez-Islas, J.A.; Campillo, B.; Chaudhary, N.; Mendoza, R.; Gonzalez, A.

    1996-08-01

    The subject of this study is related to the performance of austenitic steels coils and tubes, in a range of temperatures between 425 to 870 C for the transport of reducing gases, in an installation involving the direct reduction of iron-ore by reforming natural gas. Evidence is presented that metal dusting is not the only unique high temperature corrosion mechanism that caused catastrophic failures of austenitic 304 (UNS S30400) coils and HK-40 (UNS J94204) tubes. Sensitization as well as stress corrosion cracking occurred in 304 stainless steel coils, and metal dusting occurred in tubes of HK-40, a high resistance alloy. The role of a continuous injection of H{sub 2}S to the process is suggested to avoid the high temperature metal dusting corrosion mechanism found in these kind of installations.

  15. Oxidation and reduction of pyridine nucleotides in alamethicin-permeabilized plant mitochondria.

    PubMed Central

    Johansson, Fredrik I; Michalecka, Agnieszka M; Møller, Ian M; Rasmusson, Allan G

    2004-01-01

    The inner mitochondrial membrane is selectively permeable, which limits the transport of solutes and metabolites across the membrane. This constitutes a problem when intramitochondrial enzymes are studied. The channel-forming antibiotic AlaM (alamethicin) was used as a potentially less invasive method to permeabilize mitochondria and study the highly branched electron-transport chain in potato tuber (Solanum tuberosum) and pea leaf (Pisum sativum) mitochondria. We show that AlaM permeabilized the inner membrane of plant mitochondria to NAD(P)H, allowing the quantification of internal NAD(P)H dehydrogenases as well as matrix enzymes in situ. AlaM was found to inhibit the electron-transport chain at the external Ca2+-dependent rotenone-insensitive NADH dehydrogenase and around complexes III and IV. Nevertheless, under optimal conditions, especially complex I-mediated NADH oxidation in AlaM-treated mitochondria was much higher than what has been previously measured by other techniques. Our results also show a difference in substrate specificities for complex I in mitochondria as compared with inside-out submitochondrial particles. AlaM facilitated the passage of cofactors to and from the mitochondrial matrix and allowed the determination of NAD+ requirements of malate oxidation in situ. In summary, we conclude that AlaM provides the best method for quantifying NADH dehydrogenase activities and that AlaM will prove to be an important method to study enzymes under conditions that resemble their native environment not only in plant mitochondria but also in other membrane-enclosed compartments, such as intact cells, chloroplasts and peroxisomes. PMID:14972026

  16. Complex foamed aluminum parts as permanent cores in aluminum castings

    SciTech Connect

    Simancik, F.; Schoerghuber, F.

    1998-12-31

    The feasibility of complex shaped aluminum foam parts as permanent cores in aluminum castings has been investigated. The foamed samples were prepared by injection of the foam into sand molds. It turned out that sound castings can be produced if the foam core is properly preheated and/or surface treated before casting. The effect of the foam core on the performance of the casting was evaluated by in compression testing and by measuring structural damping. The gain in the related properties turned out to be much higher than the weight increase of the casting due to the presence of the core. The weight increase may be partially offset through a reduction of the wall-thickness of the shell.

  17. Respiratory Disorders in Aluminum Smelter Workers

    PubMed Central

    Søyseth, Vidar

    2014-01-01

    Objectives: Summarizing the knowledge status, including the morphology, possible etiological factors, and clinical expression of aluminum potroom asthma and chronic obstructive pulmonary disease related to aluminum potroom exposure. Methods: A review of the literature from the last two decades as it appears in PubMed. Results: There is substantial evidence for the existence of potroom asthma, although the incidence seems to decline over the last 10 years. Increased mortality from chronic obstructive pulmonary disease and longitudinal decline in forced expiratory volume in the first second of expiration has been shown in aluminum potroom workers. Morphological manifestations in bronchial biopsies and the inflammatory markers NO and eosinophils in airway tissue and blood are consistent with asthma in general. The causative agent(s) is (are) not known. Conclusions: Reduction of exposure and cessation of smoking seem to be the major preventive measures to avoid respiratory disorders in the aluminum industry. PMID:24806727

  18. Satellite-observed U.S. power plant NOx emission reductions and their impact on air quality

    NASA Astrophysics Data System (ADS)

    Kim, S.-W.; Heckel, A.; McKeen, S. A.; Frost, G. J.; Hsie, E.-Y.; Trainer, M. K.; Richter, A.; Burrows, J. P.; Peckham, S. E.; Grell, G. A.

    2006-11-01

    Nitrogen oxide (NOx) emissions resulting from fossil fuel combustion lead to unhealthy levels of near-surface ozone (O3). One of the largest U.S. sources, electric power generation, represented about 25% of the U.S. anthropogenic NOx emissions in 1999. Here we show that space-based instruments observed declining regional NOx levels between 1999 and 2005 in response to the recent implementation of pollution controls by utility companies in the eastern U.S. Satellite-retrieved summertime nitrogen dioxide (NO2) columns and bottom-up emission estimates show larger decreases in the Ohio River Valley, where power plants dominate NOx emissions, than in the northeast U.S. urban corridor. Model simulations predict lower O3 across much of the eastern U.S. in response to these emission reductions.

  19. Seed Biofortification and Phytic Acid Reduction: A Conflict of Interest for the Plant?

    PubMed

    Sparvoli, Francesca; Cominelli, Eleonora

    2015-11-20

    Most of the phosphorus in seeds is accumulated in the form of phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate, InsP₆). This molecule is a strong chelator of cations important for nutrition, such as iron, zinc, magnesium, and calcium. For this reason, InsP₆ is considered an antinutritional factor. In recent years, efforts to biofortify seeds through the generation of low phytic acid (lpa) mutants have been noteworthy. Moreover, genes involved in the biosynthesis and accumulation of this molecule have been isolated and characterized in different species. Beyond its role in phosphorus storage, phytic acid is a very important signaling molecule involved in different regulatory processes during plant development and responses to different stimuli. Consequently, many lpa mutants show different negative pleitotropic effects. The strength of these pleiotropic effects depends on the specific mutated gene, possible functional redundancy, the nature of the mutation, and the spatio-temporal expression of the gene. Breeding programs or transgenic approaches aimed at development of new lpa mutants must take into consideration these different aspects in order to maximize the utility of these mutants.

  20. Seed Biofortification and Phytic Acid Reduction: A Conflict of Interest for the Plant?

    PubMed Central

    Sparvoli, Francesca; Cominelli, Eleonora

    2015-01-01

    Most of the phosphorus in seeds is accumulated in the form of phytic acid (myo-inositol-1,2,3,4,5,6-hexakisphosphate, InsP6). This molecule is a strong chelator of cations important for nutrition, such as iron, zinc, magnesium, and calcium. For this reason, InsP6 is considered an antinutritional factor. In recent years, efforts to biofortify seeds through the generation of low phytic acid (lpa) mutants have been noteworthy. Moreover, genes involved in the biosynthesis and accumulation of this molecule have been isolated and characterized in different species. Beyond its role in phosphorus storage, phytic acid is a very important signaling molecule involved in different regulatory processes during plant development and responses to different stimuli. Consequently, many lpa mutants show different negative pleitotropic effects. The strength of these pleiotropic effects depends on the specific mutated gene, possible functional redundancy, the nature of the mutation, and the spatio-temporal expression of the gene. Breeding programs or transgenic approaches aimed at development of new lpa mutants must take into consideration these different aspects in order to maximize the utility of these mutants. PMID:27135349

  1. Ultrasonic treatment on activated sewage sludge from petro-plant for reduction.

    PubMed

    Yin, Xuan; Lu, Xiaoping; Han, Pingfang; Wang, Yanru

    2006-12-22

    In this essay, the influences of low frequency ultrasound (20 kHz) on dewater ability and anaerobic digestion behaviors of activated sewage sludge, obtained from Yangzi Water Treatment Plant, Yangzi Petrochemical Corporation, were discussed. Ultrasound pretreatment could enhance the filtration progress and decrease the moisture content of the sludge from 99% to 80%. Together with flocculant, the ultrasound pretreatment decreased the specific filtration resistance (SFR) of the sludge from 3.59 x 10(12) m/kg to 1.18 x 10(12) m/kg and saved about 25-50% of the flocculant dosage. Bound water of the sludge was measured by dilatometer. After 2-4 min treatment of ultrasound under intensity of 400 W/m(2), the bound water of sludge decreased from 16.7 g/g (dry base) to above 2.0 g/g (dry base). Ultrasound pretreatment could also enhance digestion and reduce digestion time. To the same resolution ratio, such as 49%, the digestion time of sludge with ultrasound pretreatment was 7 days less than that without ultrasound. Proper ultrasound pretreatment could also improve the dewater ability of the digested sludge, the final moisture of which was 73.7%.

  2. Iron release and uptake by plant ferritin: effects of pH, reduction and chelation.

    PubMed Central

    Laulhere, J P; Briat, J F

    1993-01-01

    Ferritins are iron-storage proteins that accumulate in plastids during seed formation, and also in leaves during senescence or iron overload. Iron release from ferritins occurs during growth of seedlings and greening of plastids. Depending on the concentration of the reducing agent ascorbate, either an overall iron release or uptake by ferritins from iron(III) citrate may occur. We have designed methods to measure these simultaneous and independent uptake and release fluxes. Each individual step of the exchange was studied using different iron chelates and an excess of ligand. It is shown that: (i) the chelated form of iron, and not ionic Fe3+, is the substrate for iron reduction, which controls the subsequent uptake by ferritin; (ii) iron uptake by ferritins is faster at pH 8.4 than at pH 7 or 6 and is inhibited by an excess of strongly binding free ligands; and (iii) strongly binding free ligands are inhibitory during iron release by ascorbate. When reactions are allowed to proceed simultaneously, the iron chelating power is shown to be a key factor in the overall exchange. The interactions of iron chelating power, reducing capacity and pH are discussed with regard to their influence on the biochemical mobilization of iron. Images Figure 1 Figure 6 Figure 7 PMID:8457196

  3. Effect of Silicon on Desulfurization of Aluminum-killed Steels

    NASA Astrophysics Data System (ADS)

    Roy, Debdutta

    Recent reports have suggested that silicon has a beneficial effect on the rate of desulfurization of Al-killed steel. This effect is difficult to understand looking at the overall desulfurization reaction which does not include silicon. However an explanation is proposed by taking into account the (SiO2)/[Si] equilibrium in which some Al reaching the slag-metal interface is used in reducing the SiO2 in the slag. This reaction can be suppressed to some extent if the silicon content of the metal is increased and in doing so, more Al will be available at the slag-metal interface for the desulfurization reaction and this would increase the rate of the desulfurization reaction. A model was developed, assuming the rates are controlled by mass transfer, taking into account the coupled reactions of the reduction of silica, and other unstable oxides, namely iron oxide and manganese oxide, in the slag and desulfurization reaction in the steel by aluminum. The model predicts that increasing silicon increases the rate and extent of desulfurization. Plant data was analyzed to obtain rough estimates of ladle desulfurization rates and also used to validate the model predictions. Experiments have been conducted on a kilogram scale of material in an induction furnace to test the hypothesis. The major conclusions of the study are as follows: The rate and extent of desulfurization improve with increasing initial silicon content in the steel; the effect diminishes at silicon contents higher than approximately 0.2% and with increasing slag basicity. This was confirmed with kilogram-scale laboratory experiments. The effects of the silicon content in the steel (and of initial FeO and MnO in the slag) largely arise from the dominant effects of these reactions on the equilibrium aluminum content of the steel: as far as aluminum consumption or pick-up is concerned, the Si/SiO2 reaction dominates, and desulfurization has only a minor effect on aluminum consumption. The rate is primarily

  4. Occupational dose reduction at nuclear power plants: Annotated bibliography of selected readings in radiation protection and ALARA

    SciTech Connect

    Khan, T.A.; Vulin, D.S.; Lane, S.G.; Baum, J.W. )

    1991-10-01

    In the continuing effort to collect and disseminate information on radiation dose reduction at nuclear power plants, the ALARA Center at Brookhaven National Laboratory publishes a series of bibliographies of selected readings in radiation protection and ALARA. This is the sixth report in that series. The abstracts in this bibliography were selected from proceedings of technical meetings and conferences, journals, research reports, and searches of information databases of the US Department of Energy. The subject material of these abstracts relates to radiation protection and dose reduction, and ranges from the use of robotics, to operational health physics, to water chemistry. Also included is material on the design, planning, and management of nuclear power stations, as well as on decommissioning and safe storage efforts. This report contains 266 abstracts along with subject and author indices. The author index is exclusively for this volume. The subject index contains headings for this volume in bold face, as well as reference to previous volumes. All information in this and previous volumes of the series is also available through our on-line information system called ACE (ALARA Center Exchange). ACE is accessible through fax machines or personal computers interfaced with modems. The bibliography database and other databases are kept current with new abstracts, information on research projects, and recent news of international events related to ALARA at nuclear power plants. Access to the system is provided freely to the ALARA community. For password certification, manuals, and other information about our system, please contact the ALARA CENTER, Building 703M, Brookhaven National Laboratory, Upton, NY 11973, or call (516) 282-3228.

  5. Mapping the global flow of aluminum: from liquid aluminum to end-use goods.

    PubMed

    Cullen, Jonathan M; Allwood, Julian M

    2013-04-02

    Demand for aluminum in final products has increased 30-fold since 1950 to 45 million tonnes per year, with forecasts predicting this exceptional growth to continue so that demand will reach 2-3 times today's levels by 2050. Aluminum production uses 3.5% of global electricity and causes 1% of global CO2 emissions, while meeting a 50% cut in emissions by 2050 against growing demand would require at least a 75% reduction in CO2 emissions per tonne of aluminum produced--a challenging prospect. In this paper we trace the global flows of aluminum from liquid metal to final products, revealing for the first time a complete map of the aluminum system and providing a basis for future study of the emissions abatement potential of material efficiency. The resulting Sankey diagram also draws attention to two key issues. First, around half of all liquid aluminum (~39 Mt) produced each year never reaches a final product, and a detailed discussion of these high yield losses shows significant opportunities for improvement. Second, aluminum recycling, which avoids the high energy costs and emissions of electrolysis, requires signification "dilution" (~ 8 Mt) and "cascade" (~ 6 Mt) flows of higher aluminum grades to make up for the shortfall in scrap supply and to obtain the desired alloy mix, increasing the energy required for recycling.

  6. Decontamination and reuse of ORGDP aluminum scrap

    SciTech Connect

    Compere, A.L.; Griffith, W.L.; Hayden, H.W.; Wilson, D.F.

    1996-12-01

    The Gaseous Diffusion Plants, or GDPs, have significant amounts of a number of metals, including nickel, aluminum, copper, and steel. Aluminum was used extensively throughout the GDPs because of its excellent strength to weight ratios and good resistance to corrosion by UF{sub 6}. This report is concerned with the recycle of aluminum stator and rotor blades from axial compressors. Most of the stator and rotor blades were made from 214-X aluminum casting alloy. Used compressor blades were contaminated with uranium both as a result of surface contamination and as an accumulation held in surface-connected voids inside of the blades. A variety of GDP studies were performed to evaluate the amounts of uranium retained in the blades; the volume, area, and location of voids in the blades; and connections between surface defects and voids. Based on experimental data on deposition, uranium content of the blades is 0.3%, or roughly 200 times the value expected from blade surface area. However, this value does correlate with estimated internal surface area and with lengthy deposition times. Based on a literature search, it appears that gaseous decontamination or melt refining using fluxes specific for uranium removal have the potential for removing internal contamination from aluminum blades. A melt refining process was used to recycle blades during the 1950s and 1960s. The process removed roughly one-third of the uranium from the blades. Blade cast from recycled aluminum appeared to perform as well as blades from virgin material. New melt refining and gaseous decontamination processes have been shown to provide substantially better decontamination of pure aluminum. If these techniques can be successfully adapted to treat aluminum 214-X alloy, internal and, possibly, external reuse of aluminum alloys may be possible.

  7. Biological monitoring of environmental exposure to PAHs in the vicinity of a Söderberg aluminium reduction plant.

    PubMed Central

    Gilbert, N L; Viau, C

    1997-01-01

    OBJECTIVES: To assess environmental exposure to polycyclic aromatic hydrocarbons (PAHs) in the vicinity of a Söderberg aluminium reduction plant in Shawinigan, Canada with urinary 1-hydroxypyrene (1-OHP) as a biomarker. METHODS: Urine samples were collected from 20 non-occupationally exposed subjects living less than 500 m from the plant and from 20 controls living in Trois-Rivières, another industrial town 40 km from Shawinigan. Concentrations of 1-OHP were measured by high performance liquid chromatography (HPLC). RESULTS: Among controls, geometric mean (range) 1-OHP concentrations were 0.046 (0.012-0.116) mumol/mol creatinine in non-smokers and 0.125 (0.051-0.282) mumol/mol creatinine in smokers. Among exposed subjects, values were 0.103 (0.056-0.196) mumol/mol creatinine in non-smokers and 0.250 (0.112-0.448) mumol/mol creatinine in smokers. Excretion of 1-OHP was significantly higher in exposed subjects than in controls among non-smokers and smokers (P < 0.05). CONCLUSION: Based on urinary 1-OHP as a biomarker, it seems that living near an industrial point source of PAHs is associated with higher exposure. The health significance of this finding will require further investigation. PMID:9326167

  8. Formation of multinary intermetallics from reduction of perovskites by aluminum flux: M(3)Au(6+)(x)()Al(26)Ti (M = Ca, Sr, Yb), a stuffed variant of the BaHg(11) type.

    PubMed

    Latturner, Susan E; Kanatzidis, Mercouri G

    2004-01-12

    New intermetallic phases were synthesized by reacting oxidic perovskites and gold metal in aluminum flux. The combination of MTiO(3) (M = Ca, Sr, Ba) and Au metal in excess molten aluminum produces quaternary compounds M(3)Au(6+)(x)()Al(26)Ti with a stuffed BaHg(11) structure type. An analogue with M = Yb was also synthesized; it shows mixed valent behavior.

  9. Occupational dose reduction at nuclear power plants: Annotated bibliography of selected readings in radiation protection and ALARA. Volume 7

    SciTech Connect

    Kaurin, D.G.; Khan, T.A.; Sullivan, S.G.; Baum, J.W.

    1993-07-01

    The ALARA Center at Brookhaven National Laboratory publishes a series of bibliographies of selected readings in radiation protection and ALARA in the continuing effort to collect and disseminate information on radiation dose reduction at nuclear power plants. This is volume 7 of the series. The abstracts in this bibliography were selected from proceedings of technical meetings and conferences, journals, research reports, and searches of the Energy Science and Technology database of the US Department of Energy. The subject material of these abstracts relates to radiation protection and dose reduction, and ranges from use of robotics to operational health physics, to water chemistry. Material on the design, planning, and management of nuclear power stations is included, as well as information on decommissioning and safe storage efforts. Volume 7 contains 293 abstract, an author index, and a subject index. The author index is specific for this volume. The subject index is cumulative and lists all abstract numbers from volumes 1 to 7. The numbers in boldface indicate the abstracts in this volume; the numbers not in boldface represent abstracts in previous volumes.

  10. Effect of selective catalytic reduction (SCR) on fine particle emission from two coal-fired power plants in China

    NASA Astrophysics Data System (ADS)

    Li, Zhen; Jiang, Jingkun; Ma, Zizhen; Wang, Shuxiao; Duan, Lei

    2015-11-01

    Nitrogen oxides (NOx) emission abatement of coal-fired power plants (CFPPs) requires large-scaled installation of selective catalytic reduction (SCR), which would reduce secondary fine particulate matter (PM2.5) (by reducing nitrate aerosol) in the atmosphere. However, our field measurement of two CFPPs equipped with SCR indicates a significant increase of SO42- and NH4+ emission in primary PM2.5, due to catalytic enhancement of SO2 oxidation to SO3 and introducing of NH3 as reducing agent. The subsequent formation of (NH4)2SO4 or NH4HSO4 aerosol is commonly concentrated in sub-micrometer particulate matter (PM1) with a bimodal pattern. The measurement at the inlet of stack also showed doubled primary PM2.5 emission by SCR operation. This effect should therefore be considered when updating emission inventory of CFPPs. By rough estimation, the enhanced primary PM2.5 emission from CFPPs by SCR operation would offset 12% of the ambient PM2.5 concentration reduction in cities as the benefit of national NOx emission abatement, which should draw attention of policy-makers for air pollution control.

  11. Occupational dose reduction at nuclear power plants: Annotated bibliography of selected readings in radiation protection and ALARA. Volume 8

    SciTech Connect

    Sullivan, S.G.; Khan, T.A.; Xie, J.W.

    1995-05-01

    The ALARA Center at Brookhaven National Laboratory publishes a series of bibliographies of selected readings in radiation protection and ALARA in a continuing effort to collect and disseminate information on radiation dose reduction at nuclear power plants. This volume 8 of the series. The abstracts in this bibliography were selected form proceedings of technical meetings and conference journals, research reports, and searches of the Energy Science and Technology database of the US Department of Energy. The subject material of these abstracts relates to the many aspects of radiation protection and dose reduction, and ranges form use of robotics, to operational health physics, to water chemistry. Material on the design, planning, and management of nuclear power stations is included, as well as information on decommissioning and safe storage efforts. Volume 8 contains 232 abstracts, an author index, and a subject index. The author index is specific for this volume. The subject index is cumulative and lists all abstract numbers from volumes 1 to 8. The numbers in boldface indicate the abstracts in this volume; the numbers not in boldface represent abstracts in previous volumes.

  12. Electrolytic production of high purity aluminum using ceramic inert anodes

    DOEpatents

    Ray, Siba P.; Liu, Xinghua; Weirauch, Douglas A.; DiMilia, Robert A.; Dynys, Joseph M.; Phelps, Frankie E.; LaCamera, Alfred F.

    2002-01-01

    A method of producing commercial purity aluminum in an electrolytic reduction cell comprising ceramic inert anodes is disclosed. The method produces aluminum having acceptable levels of Fe, Cu and Ni impurities. The ceramic inert anodes used in the process may comprise oxides containing Fe and Ni, as well as other oxides, metals and/or dopants.

  13. Electrolytic production of high purity aluminum using inert anodes

    DOEpatents

    Ray, Siba P.; Liu, Xinghua; Weirauch, Jr., Douglas A.

    2001-01-01

    A method of producing commercial purity aluminum in an electrolytic reduction cell comprising inert anodes is disclosed. The method produces aluminum having acceptable levels of Fe, Cu and Ni impurities. The inert anodes used in the process preferably comprise a cermet material comprising ceramic oxide phase portions and metal phase portions.

  14. Spectral properties of plant leaves pertaining to urban landscape design of broad-spectrum solar ultraviolet radiation reduction.

    PubMed

    Yoshimura, Haruka; Zhu, Hui; Wu, Yunying; Ma, Ruijun

    2010-03-01

    Human exposure to harmful ultraviolet (UV) radiation has important public health implications. Actual human exposure to solar UV radiation depends on ambient UV irradiance, and the latter is influenced by ground reflection. In urban areas with higher reflectivity, UV exposure occurs routinely. To discover the solar UV radiation regulation mechanism of vegetation, the spectral reflectance and transmittance of plant leaves were measured with a spectrophotometer. Typically, higher plants have low leaf reflectance (around 5%) and essentially zero transmittance throughout the UV region regardless of plant species and seasonal change. Accordingly, incident UV radiation decreases to 5% by being reflected and is reduced to zero by passing through a leaf. Therefore, stratified structures of vegetation are working as another terminator of UV rays, protecting whole terrestrial ecosystems, while vegetation at waterfronts contributes to protect aquatic ecosystems. It is possible to protect the human population from harmful UV radiation by urban landscape design of tree shade and the botanical environment. Even thin but uniformly distributed canopy is effective in attenuating UV radiation. To intercept diffuse radiation, UV screening by vertical structures such as hedges should be considered. Reflectivity of vegetation is around 2%, as foliage surfaces reduce incident UV radiation via reflection, while also eliminating it by transmittance. Accordingly, vegetation reduces incident UV radiation to around 2% by reflection. Vegetation influence on ambient UV radiation is broad-spectrum throughout the UV region. Only trees provide cool UV protective shade. Urban landscapes aimed at abating urban heat islands integrated with a reduction of human UV over-exposure would contribute to mitigation of climate change.

  15. Aluminum: Recycling of Aluminum Dross/Saltcake

    SciTech Connect

    Blazek, S.

    1999-01-29

    As this NICE3 publication details, the objective of this project is to commercialize the process technology to eliminate all landfill waste associated with black dross and saltcake generated from aluminum recycling in the United States.

  16. Removal of micropollutants and reduction of biological activity in a full scale reclamation plant using ozonation and activated carbon filtration.

    PubMed

    Reungoat, J; Macova, M; Escher, B I; Carswell, S; Mueller, J F; Keller, J

    2010-01-01

    Pharmaceutical compounds are found in secondary treated effluents up to microg L(-1) levels and therefore discharged into surface waters. Since the long term effects of these compounds on the environment and human health are, to date, largely unknown, implementation of advanced treatment of wastewaters is envisaged to reduce their discharge. This is of particular relevance where surface waters are used as drinking water sources and when considering indirect potable reuse. This study aimed at assessing the removal of organic micropollutants and the concurrent reduction of their biological activity in a full scale reclamation plant treating secondary effluent. The treatment consists of 6 stages: denitrification, pre-ozonation, coagulation/flocculation/dissolved air flotation and filtration (DAFF), main ozonation, activated carbon filtration and final ozonation for disinfection. For that purpose, representative 24-hour composite samples were collected after each stage. The occurrence of 85 compounds was monitored by LC/MS-MS. A battery of 6 bioassays was also used as a complementary tool to evaluate non-specific toxicity and 5 specific toxic modes of action. Results show that, among the 54 micropollutants quantified in the influent water, 50 were removed to below their limit of quantification representing more than 90% of concentration reduction. Biological activity was reduced, depending on the specific response that was assessed, from a minimum of 62% (AhR response) to more than 99% (estrogenicity). The key processes responsible for the plant's performances were the coagulation/flocculation/DAFF, main ozonation and activated carbon filtration. The effect of these 3 processes varied from one compound or bioassay to another but their combination was almost totally responsible for the overall observed reduction. Bioassays yielded complementary information, e.g. estrogenic compounds were not detected in the secondary effluent by chemical analysis, but the samples had an

  17. Meta-Analysis of the Reduction of Norovirus and Male-Specific Coliphage Concentrations in Wastewater Treatment Plants.

    PubMed

    Pouillot, Régis; Van Doren, Jane M; Woods, Jacquelina; Plante, Daniel; Smith, Mark; Goblick, Gregory; Roberts, Christopher; Locas, Annie; Hajen, Walter; Stobo, Jeffrey; White, John; Holtzman, Jennifer; Buenaventura, Enrico; Burkhardt, William; Catford, Angela; Edwards, Robyn; DePaola, Angelo; Calci, Kevin R

    2015-07-01

    Human norovirus (NoV) is the leading cause of foodborne illness in the United States and Canada. Wastewater treatment plant (WWTP) effluents impacting bivalve mollusk-growing areas are potential sources of NoV contamination. We have developed a meta-analysis that evaluates WWTP influent concentrations and log10 reductions of NoV genotype I (NoV GI; in numbers of genome copies per liter [gc/liter]), NoV genotype II (NoV GII; in gc/liter), and male-specific coliphage (MSC; in number of PFU per liter), a proposed viral surrogate for NoV. The meta-analysis included relevant data (2,943 measurements) reported in the scientific literature through September 2013 and previously unpublished surveillance data from the United States and Canada. Model results indicated that the mean WWTP influent concentration of NoV GII (3.9 log10 gc/liter; 95% credible interval [CI], 3.5, 4.3 log10 gc/liter) is larger than the value for NoV GI (1.5 log10 gc/liter; 95% CI, 0.4, 2.4 log10 gc/liter), with large variations occurring from one WWTP to another. For WWTPs with mechanical systems and chlorine disinfection, mean log10 reductions were -2.4 log10 gc/liter (95% CI, -3.9, -1.1 log10 gc/liter) for NoV GI, -2.7 log10 gc/liter (95% CI, -3.6, -1.9 log10 gc/liter) for NoV GII, and -2.9 log10 PFU per liter (95% CI, -3.4, -2.4 log10 PFU per liter) for MSCs. Comparable values for WWTPs with lagoon systems and chlorine disinfection were -1.4 log10 gc/liter (95% CI, -3.3, 0.5 log10 gc/liter) for NoV GI, -1.7 log10 gc/liter (95% CI, -3.1, -0.3 log10 gc/liter) for NoV GII, and -3.6 log10 PFU per liter (95% CI, -4.8, -2.4 PFU per liter) for MSCs. Within WWTPs, correlations exist between mean NoV GI and NoV GII influent concentrations and between the mean log10 reduction in NoV GII and the mean log10 reduction in MSCs. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  18. Meta-Analysis of the Reduction of Norovirus and Male-Specific Coliphage Concentrations in Wastewater Treatment Plants

    PubMed Central

    Pouillot, Régis; Van Doren, Jane M.; Woods, Jacquelina; Plante, Daniel; Smith, Mark; Goblick, Gregory; Roberts, Christopher; Locas, Annie; Hajen, Walter; Stobo, Jeffrey; White, John; Holtzman, Jennifer; Buenaventura, Enrico; Burkhardt, William; Catford, Angela; Edwards, Robyn; DePaola, Angelo

    2015-01-01

    Human norovirus (NoV) is the leading cause of foodborne illness in the United States and Canada. Wastewater treatment plant (WWTP) effluents impacting bivalve mollusk-growing areas are potential sources of NoV contamination. We have developed a meta-analysis that evaluates WWTP influent concentrations and log10 reductions of NoV genotype I (NoV GI; in numbers of genome copies per liter [gc/liter]), NoV genotype II (NoV GII; in gc/liter), and male-specific coliphage (MSC; in number of PFU per liter), a proposed viral surrogate for NoV. The meta-analysis included relevant data (2,943 measurements) reported in the scientific literature through September 2013 and previously unpublished surveillance data from the United States and Canada. Model results indicated that the mean WWTP influent concentration of NoV GII (3.9 log10 gc/liter; 95% credible interval [CI], 3.5, 4.3 log10 gc/liter) is larger than the value for NoV GI (1.5 log10 gc/liter; 95% CI, 0.4, 2.4 log10 gc/liter), with large variations occurring from one WWTP to another. For WWTPs with mechanical systems and chlorine disinfection, mean log10 reductions were −2.4 log10 gc/liter (95% CI, −3.9, −1.1 log10 gc/liter) for NoV GI, −2.7 log10 gc/liter (95% CI, −3.6, −1.9 log10 gc/liter) for NoV GII, and −2.9 log10 PFU per liter (95% CI, −3.4, −2.4 log10 PFU per liter) for MSCs. Comparable values for WWTPs with lagoon systems and chlorine disinfection were −1.4 log10 gc/liter (95% CI, −3.3, 0.5 log10 gc/liter) for NoV GI, −1.7 log10 gc/liter (95% CI, −3.1, −0.3 log10 gc/liter) for NoV GII, and −3.6 log10 PFU per liter (95% CI, −4.8, −2.4 PFU per liter) for MSCs. Within WWTPs, correlations exist between mean NoV GI and NoV GII influent concentrations and between the mean log10 reduction in NoV GII and the mean log10 reduction in MSCs. PMID:25934626

  19. Aspects of aluminum toxicity

    SciTech Connect

    Hewitt, C.D.; Savory, J.; Wills, M.R. )

    1990-06-01

    Aluminum is the most abundant metal in the earth's crust. The widespread occurrence of aluminum, both in the environment and in foodstuffs, makes it virtually impossible for man to avoid exposure to this metal ion. Attention was first drawn to the potential role of aluminum as a toxic metal over 50 years ago, but was dismissed as a toxic agent as recently as 15 years ago. The accumulation of aluminum, in some patients with chronic renal failure, is associated with the development of toxic phenomena; dialysis encephalopathy, osteomalacic dialysis osteodystrophy, and an anemia. Aluminum accumulation also occurs in patients who are not on dialysis, predominantly infants and children with immature or impaired renal function. Aluminum has also been implicated as a toxic agent in the etiology of Alzheimer's disease, Guamiam amyotrophic lateral sclerosis, and parkinsonism-dementia. 119 references.

  20. Analysis on Reduction of Greenhouse Gas Emissions by the Introduction of a Bio-methane Production Plant Using Dairy Cow Slurry as the Main Ingredient, and Management Balance of the Plant

    NASA Astrophysics Data System (ADS)

    Ohkubo, Takashi; Hideshima, Yoshiaki; Shudo, Yukoh; Ohmiya, Kazuhiko

    A study was conducted on a system to refine biogas generated from a biogas plant, which uses cow slurry as its main ingredient, and use the bio-methane as a regional energy supply source. Based on the data obtained by the demonstrative operation of the biogas plant and bio-methane production experiments, a bio-methane production plant that can process waste from 1,000 dairy cows was assumed, and optimization of plant operation was attempted using the linear programming method with maximum environmental friendliness (reduction of greenhouse gas emissions) and economic efficiency (management balance of the plant) as the target functions. The results revealed that plant operation methods varied according to the target of optimization. Environmental friendliness and economic efficiency were in a trade-off relationship with each other, but in the case where the greatest importance was placed on economic efficiency, greenhouse gas emissions were equivalent to that in the case where the greatest importance was placed on environmental friendliness itself. However, the values of economic efficiency were negative in both cases, indicating that it is difficult to make the plant management economically feasible under the current circumstances. To make the plant management balance positive, it is necessary to take measures, such as reduction of plant construction costs and exemption from interest costs. In addition, as a future direction for such regional bio-methane use, a micro grid system with a dispersed power source using bio-methane as raw fuel was presented.

  1. BONDING ALUMINUM METALS

    DOEpatents

    Noland, R.A.; Walker, D.E.

    1961-06-13

    A process is given for bonding aluminum to aluminum. Silicon powder is applied to at least one of the two surfaces of the two elements to be bonded, the two elements are assembled and rubbed against each other at room temperature whereby any oxide film is ruptured by the silicon crystals in the interface; thereafter heat and pressure are applied whereby an aluminum-silicon alloy is formed, squeezed out from the interface together with any oxide film, and the elements are bonded.

  2. Aluminum powder metallurgy processing

    SciTech Connect

    Flumerfelt, J.F.

    1999-02-12

    The objective of this dissertation is to explore the hypothesis that there is a strong linkage between gas atomization processing conditions, as-atomized aluminum powder characteristics, and the consolidation methodology required to make components from aluminum powder. The hypothesis was tested with pure aluminum powders produced by commercial air atomization, commercial inert gas atomization, and gas atomization reaction synthesis (GARS). A comparison of the GARS aluminum powders with the commercial aluminum powders showed the former to exhibit superior powder characteristics. The powders were compared in terms of size and shape, bulk chemistry, surface oxide chemistry and structure, and oxide film thickness. Minimum explosive concentration measurements assessed the dependence of explosibility hazard on surface area, oxide film thickness, and gas atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization oxidation of aluminum powder. An Al-Ti-Y GARS alloy exposed in ambient air at different temperatures revealed the effect of reactive alloy elements on post-atomization powder oxidation. The pure aluminum powders were consolidated by two different routes, a conventional consolidation process for fabricating aerospace components with aluminum powder and a proposed alternative. The consolidation procedures were compared by evaluating the consolidated microstructures and the corresponding mechanical properties. A low temperature solid state sintering experiment demonstrated that tap densified GARS aluminum powders can form sintering necks between contacting powder particles, unlike the total resistance to sintering of commercial air atomization aluminum powder.

  3. Aluminum Cartridge Case Concept

    DTIC Science & Technology

    2005-05-01

    carried by the soldier, a lightweight alternative to the brass cartridge case is an aluminum cartridge case. This comprehensive detailed report describes...AD AD-E403 044 Technical Report ARAEW-TR-05003 ALUMINUM CARTRIDGE CASE CONCEPT Brian Tasson ATK Ordnance and Ground Systems LLC 4700 Nathan Lane...TITLE AND SUBTITLE 5a. CONTRACT NUMBER DAAE30-03-C-1 128 ALUMINUM CARTRIDGE CASE CONCEPT 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHORS 5d

  4. Wastewater sludge dewaterability enhancement using hydroxyl aluminum conditioning: Role of aluminum speciation.

    PubMed

    Cao, Bingdi; Zhang, Weijun; Wang, Qiandi; Huang, Yangrui; Meng, Chenrui; Wang, Dongsheng

    2016-11-15

    Chemical conditioning is one of the most important processes for improve the performance of sludge dewatering device. Aluminum salt coagulant has been widely used in wastewater and sludge treatment. It is generally accepted that pre-formed speciation of aluminum salt coagulants (ASC) has an important influence on coagulation/flocculation performance. In this study, the interaction mechanisms between sludge particles and aluminum salt coagulants with different speciation of hydroxy aluminum were investigated by characterizing the changes in morphological and EPS properties. It was found that middle polymer state aluminum (Alb) and high polymer state aluminum (Alc) performed better than monomer aluminum and oligomeric state aluminum (Ala) in reduction of specific resistance to filtration (SRF) and compressibility of wastewater sludge due to their higher charge neutralization and formed more compact flocs. Sludge was significantly acidified after addition Ala, while pH was much more stable under Alb and Alc conditioning due to their hydrolysis stability. The size of sludge flocs conditioned with Alb and Alc was small but flocs structure was denser and more compact, and floc strength is higher, while that formed from Ala is relatively large, but floc structure was loose, floc strength is relatively lower. Scanning environmental microscope analysis revealed that sludge flocs conditioned by Alb and Alc (especially PAC2.5 and Al13) exhibited obvious botryoidal structure, this is because sludge flocs formed by Alb and Alc were more compact and floc strength is high, it was easy generated plentiful tiny channels for water release. In addition, polymeric aluminum salt coagulant (Alb, Alc) had better performance in compressing extracellular polymeric substances (EPS) structure and removing sticky protein-like substances from soluble EPS fraction, contributing to improvement of sludge filtration performance. Therefore, this study provides a novel solution for improving sludge

  5. Effects of aluminum-copper alloy filtration on photon spectra, air kerma rate and image contrast.

    PubMed

    Gonçalves, Andréa; Rollo, João Manuel Domingos de Almeida; Gonçalves, Marcelo; Haiter Neto, Francisco; Bóscolo, Frab Norberto

    2004-01-01

    This study evaluated the performance of aluminum-copper alloy filtration, without the original aluminum filter, for dental radiography in terms of x-ray energy spectrum, air kerma rate and image quality. Comparisons of various thicknesses of aluminum-copper alloy in three different percentages were made with aluminum filtration. Tests were conducted on an intra-oral dental x-ray machine and were made on mandible phantom and on step-wedge. Depending on the thickness of aluminum-copper alloy filtration, the beam could be hardened and filtrated. The use of the aluminum-copper alloy filter resulted in reductions in air kerma rate from 8.40% to 47.33%, and indicated the same image contrast when compared to aluminum filtration. Aluminum-copper alloy filtration may be considered a good alternative to aluminum filtration.

  6. Evaluation of aluminum tolerance in grapevine rootstocks

    USDA-ARS?s Scientific Manuscript database

    Aluminum (Al) toxicity is a major worldwide agricultural problem. At low pH, Al speciates into the soluble and phyto-toxic form Al3+, causing inhibition of root growth and affecting plant development. In Brazil, agriculture in acidic soils regions with elevated concentration of Al has significantly ...

  7. Reduction of photosynthetic sensitivity in response to abiotic stress in tomato is mediated by a new generation plant activator

    PubMed Central

    2013-01-01

    Background Yield losses as a result of abiotic stress factors present a significant challenge for the future of global food production. While breeding technologies provide potential to combat negative stress-mediated outcomes over time, interventions which act to prime plant tolerance to stress, via the use of phytohormone-based elicitors for example, could act as a valuable tool for crop protection. However, the translation of fundamental biology into functioning solution is often constrained by knowledge-gaps. Results Photosynthetic and transcriptomic responses were characterised in young tomato (Solanum lycopersicum L.) seedlings in response to pre-treatment with a new plant health activator technology, ‘Alethea’, followed by a subsequent 100 mM salinity stress. Alethea is a novel proprietary technology composed of three key constituent compounds; the hitherto unexplored compound potassium dihydrojasmonate, an analogue of jasmonic acid; sodium benzoate, a carboxylic acid precursor to salicylic acid, and the α-amino acid L-arginine. Salinity treatment led to a maximal 47% reduction in net photosynthetic rate 8 d following NaCl treatment, yet in Alethea pre-treated seedlings, sensitivity to salinity stress was markedly reduced during the experimental period. Microarray analysis of leaf transcriptional responses showed that while salinity stress and Alethea individually impacted on largely non-overlapping, distinct groups of genes, Alethea pre-treatment substantially modified the response to salinity. Alethea affected the expression of genes related to biotic stress, ethylene signalling, cell wall synthesis, redox signalling and photosynthetic processes. Since Alethea had clear effects on photosynthesis/chloroplastic function at the physiological and molecular levels, we also investigated the ability of Alethea to protect various crop species against methyl viologen, a potent generator of oxidative stress in chloroplasts. Alethea pre-treatment produced

  8. Body fat mass reduction and up-regulation of uncoupling protein by novel lipolysis-promoting plant extract.

    PubMed

    Mori, Shinobu; Satou, Mayumi; Kanazawa, Satoshi; Yoshizuka, Naonobu; Hase, Tadashi; Tokimitsu, Ichiro; Takema, Yoshinori; Nishizawa, Yoshinori; Yada, Toshihiko

    2009-01-01

    We have found natural products exhibiting lipolysis-promoting activity in subcutaneous adipocytes, which are less sensitive to hormones than visceral adipocytes. The activities and a action mechanisms of a novel plant extract of Cirsium oligophyllum (CE) were investigated in isolated adipocytes from rat subcutaneous fat, and its fat-reducing effects by peroral administration and topical application were evaluated in vivo. CE-induced lipolysis was synergistically enhanced by caffeine, a phosphodiesterase inhibitor, and was reduced by propranolol, a beta adrenergic antagonist. The peroral administration of 10% CE solution to Wistar rats for 32 days reduced body weight gain, subcutaneous, and visceral fat weights by 6.6, 26.2, and 3.0%, respectively, as compared to the control group. By the topical application of 2% of this extract to rats for 7 days, weight of subcutaneous fat in the treated skin was reduced by 23.2%. This fat mass reduction was accompanied by the up-regulation of uncoupling protein 1 (UCP), a principal thermogenic mitochondrial molecule related to energy dissipating, in subcutaneous fat and UCP3 in skin except for the fat layer. These results indicate that CE promotes lipolysis via a mechanism involving the beta adrenergic receptor, and affects the body fat mass. This fat reduction may be partially due to UCP up-regulation in the skin including subcutaneous fat. This is the first report showing that repeated lipolysis promotion through CE administration may be beneficial for the systematic suppression of body fat accumulation or the control of fat distribution in obesity.

  9. Reduction of Cross-Reactive Carbohydrate Determinants in Plant Foodstuff: Elucidation of Clinical Relevance and Implications for Allergy Diagnosis

    PubMed Central

    Brehler, Randolf; von Schaewen, Antje

    2011-01-01

    Background A longstanding debate in allergy is whether or not specific immunoglobulin-E antibodies (sIgE), recognizing cross-reactive carbohydrate determinants (CCD), are able to elicit clinical symptoms. In pollen and food allergy, ≥20% of patients display in-vitro CCD reactivity based on presence of α1,3-fucose and/or β1,2-xylose residues on N-glycans of plant (xylose/fucose) and insect (fucose) glycoproteins. Because the allergenicity of tomato glycoallergen Lyc e 2 was ascribed to N-glycan chains alone, this study aimed at evaluating clinical relevance of CCD-reduced foodstuff in patients with carbohydrate-specific IgE (CCD-sIgE). Methodology/Principal Findings Tomato and/or potato plants with stable reduction of Lyc e 2 (tomato) or CCD formation in general were obtained via RNA interference, and gene-silencing was confirmed by immunoblot analyses. Two different CCD-positive patient groups were compared: one with tomato and/or potato food allergy and another with hymenoptera-venom allergy (the latter to distinguish between CCD- and peptide-specific reactions in the food-allergic group). Non-allergic and CCD-negative food-allergic patients served as controls for immunoblot, basophil activation, and ImmunoCAP analyses. Basophil activation tests (BAT) revealed that Lyc e 2 is no key player among other tomato (glyco)allergens. CCD-positive patients showed decreased (re)activity with CCD-reduced foodstuff, most obvious in the hymenoptera venom-allergic but less in the food-allergic group, suggesting that in-vivo reactivity is primarily based on peptide- and not CCD-sIgE. Peptide epitopes remained unaffected in CCD-reduced plants, because CCD-negative patient sera showed reactivity similar to wild-type. In-house-made ImmunoCAPs, applied to investigate feasibility in routine diagnosis, confirmed BAT results at the sIgE level. Conclusions/Significance CCD-positive hymenoptera venom-allergic patients (control group) showed basophil activation despite no allergic

  10. High energy density aluminum battery

    DOEpatents

    Brown, Gilbert M.; Paranthaman, Mariappan Parans; Dai, Sheng; Dudney, Nancy J.; Manthiram, Arumugan; McIntyre, Timothy J.; Sun, Xiao-Guang; Liu, Hansan

    2016-10-11

    Compositions and methods of making are provided for a high energy density aluminum battery. The battery comprises an anode comprising aluminum metal. The battery further comprises a cathode comprising a material capable of intercalating aluminum or lithium ions during a discharge cycle and deintercalating the aluminum or lithium ions during a charge cycle. The battery further comprises an electrolyte capable of supporting reversible deposition and stripping of aluminum at the anode, and reversible intercalation and deintercalation of aluminum or lithium at the cathode.

  11. Low Temperature Aluminum Dissolution Of Sludge Waste

    SciTech Connect

    Keefer, M.T.; Hamm, B.A.; Pike, J.A.

    2008-07-01

    High Level Waste (HLW) at the Savannah River Site (SRS) is currently stored in aging underground storage tanks. This waste is a complex mixture of insoluble solids, referred to as sludge, and soluble salts. Continued long-term storage of these radioactive wastes poses an environmental risk. The sludge is currently being stabilized in the Defense Waste Processing Facility (DWPF) through a vitrification process immobilizing the waste in a borosilicate glass matrix for long-term storage in a federal repository. Without additional treatment, the existing volume of sludge would produce nearly 8000 canisters of vitrified waste. Aluminum compounds, along with other non-radioactive components, represent a significant portion of the sludge mass currently planned for vitrification processing in DWPF. Removing the aluminum from the waste stream reduces the volume of sludge requiring vitrification and improves production rates. Treating the sludge with a concentrated sodium hydroxide (caustic) solution at elevated temperatures (>90 deg. C) to remove aluminum is part of an overall sludge mass reduction effort to reduce the number of vitrified canisters, shorten the life cycle for the HLW system, and reduce the risk associated with the long term storage of radioactive wastes at SRS. A projected reduction of nearly 900 canisters will be achieved by performing aluminum dissolution on six targeted sludge batches; however, a project to develop and install equipment will not be ready for operation until 2013. The associated upgrades necessary to implement a high temperature process in existing facilities are costly and present many technical challenges. Efforts to better understand the characteristics of the sludge mass and dissolution kinetics are warranted to overcome these challenges. Opportunities to further reduce the amount of vitrified waste and increase production rates should also be pursued. Sludge staged in Tank 51 as the next sludge batch for feed to DWPF consisted

  12. Role of Arabidopsis UV RESISTANCE LOCUS 8 in plant growth reduction under osmotic stress and low levels of UV-B.

    PubMed

    Fasano, Rossella; Gonzalez, Nathalie; Tosco, Alessandra; Dal Piaz, Fabrizio; Docimo, Teresa; Serrano, Ramon; Grillo, Stefania; Leone, Antonella; Inzé, Dirk

    2014-05-01

    In high-light environments, plants are exposed to different types of stresses, such as an excess of UV-B, but also drought stress which triggers a common morphogenic adaptive response resulting in a general reduction of plant growth. Here, we report that the Arabidopsis thaliana UV RESISTANCE LOCUS 8 (UVR8) gene, a known regulator of the UV-B morphogenic response, was able to complement a Saccharomyces cerevisiae osmo-sensitive mutant and its expression was induced after osmotic or salt stress in Arabidopsis plants. Under low levels of UV-B, plants overexpressing UVR8 are dwarfed with a reduced root development and accumulate more flavonoids compared to control plants. The growth defects are mainly due to the inhibition of cell expansion. The growth inhibition triggered by UVR8 overexpression in plants under low levels of UV-B was exacerbated by mannitol-induced osmotic stress, but it was not significantly affected by ionic stress. In contrast, uvr8-6 mutant plants do not differ from wild-type plants under standard conditions, but they show an increased shoot growth under high-salt stress. Our data suggest that UVR8-mediated accumulation of flavonoid and possibly changes in auxin homeostasis are the underlying mechanism of the observed growth phenotypes and that UVR8 might have an important role for integrating plant growth and stress signals.

  13. Restoring Southern Pine Forests Ecosystems: Plant Community Response to Mechanical Midstory History Reduction and Prescribed Fire on Sandhills at Fort Benning Georgia

    Treesearch

    Dale Brockway; Kenneth W. Outcalt; Becky L. Estes

    2003-01-01

    Developed during periods of fire exclusion, dense midstory vegetation, that reduces understory plant diversity (competitive shading) and increases the risk of damaging Wildfire (fuel ladder from ground to canopy), has impeded restoration efforts to safely reintroduce prescribed burning in southern pine ecosystems. Our study evaluated the effects of midstory reduction...

  14. Optimization of coagulation with ferric chloride as a pretreatment for fouling reduction during nanofiltration of rendering plant secondary effluent.

    PubMed

    Racar, Marko; Dolar, Davor; Špehar, Ana; Kraš, Ana; Košutić, Krešimir

    2017-08-01

    The treatment and reuse of rendering plant wastewater with membrane processes is a poorly investigated area that could result in substantial water savings. Membrane fouling is still the main obstacle when treating secondary effluents (SEs) with high content of effluent organic matter (EfOM). Thus, the optimization of coagulation with ferric(III) chloride (FeCl3) as a pretreatment for nanofiltration was performed to reduce membrane fouling and achieve higher permeate quality. Coagulation was modeled (total carbon, inorganic carbon, dissolved organic carbon (DOC), turbidity, conductivity, and resulting pH) and optimized with response surface methodology (RSM) to remove DOC and turbidity with a pH close to neutral. The effluent after coagulation at optimal conditions (5.58 pH and 26.38 mg L(-1) of Fe(3+)) and sand filtration (SF) was subjected to nanofiltration (NF270, NF, and NF90 membranes). The fouling was compared to evaluate the efficiency of each pretreatment. Coagulation with FeCl3 reduced the flux decline of nanofiltration membranes 4.2 to 19.3 times while SF barely reduced the fouling. Coagulation increased the flux recovery and chemical cleanliness after the membrane washing. In addition to fouling reduction, higher permeate quality was achieved. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Is the Aluminum Hypothesis Dead?

    PubMed Central

    2014-01-01

    The Aluminum Hypothesis, the idea that aluminum exposure is involved in the etiology of Alzheimer disease, dates back to a 1965 demonstration that aluminum causes neurofibrillary tangles in the brains of rabbits. Initially the focus of intensive research, the Aluminum Hypothesis has gradually been abandoned by most researchers. Yet, despite this current indifference, the Aluminum Hypothesis continues to attract the attention of a small group of scientists and aluminum continues to be viewed with concern by some of the public. This review article discusses reasons that mainstream science has largely abandoned the Aluminum Hypothesis and explores a possible reason for some in the general public continuing to view aluminum with mistrust. PMID:24806729

  16. Is the Aluminum Hypothesis dead?

    PubMed

    Lidsky, Theodore I

    2014-05-01

    The Aluminum Hypothesis, the idea that aluminum exposure is involved in the etiology of Alzheimer disease, dates back to a 1965 demonstration that aluminum causes neurofibrillary tangles in the brains of rabbits. Initially the focus of intensive research, the Aluminum Hypothesis has gradually been abandoned by most researchers. Yet, despite this current indifference, the Aluminum Hypothesis continues to attract the attention of a small group of scientists and aluminum continues to be viewed with concern by some of the public. This review article discusses reasons that mainstream science has largely abandoned the Aluminum Hypothesis and explores a possible reason for some in the general public continuing to view aluminum with mistrust.

  17. Anodizing Aluminum with Frills.

    ERIC Educational Resources Information Center

    Doeltz, Anne E.; And Others

    1983-01-01

    "Anodizing Aluminum" (previously reported in this journal) describes a vivid/relevant laboratory experience for general chemistry students explaining the anodizing of aluminum in sulfuric acid and constrasting it to electroplating. Additions to this procedure and the experiment in which they are used are discussed. Reactions involved are…

  18. Aluminum space frame technology

    SciTech Connect

    Birch, S.

    1994-01-01

    This article examines the increased application of aluminum to the construction of automobile frames. The topics of the article include a joint venture between Audi and Alcoa, forms in which aluminum is used, new alloys and construction methods, meeting rigidity and safety levels, manufacturing techniques, the use of extrusions, die casting, joining techniques, and pollution control during manufacturing.

  19. Anodizing Aluminum with Frills.

    ERIC Educational Resources Information Center

    Doeltz, Anne E.; And Others

    1983-01-01

    "Anodizing Aluminum" (previously reported in this journal) describes a vivid/relevant laboratory experience for general chemistry students explaining the anodizing of aluminum in sulfuric acid and constrasting it to electroplating. Additions to this procedure and the experiment in which they are used are discussed. Reactions involved are…

  20. In vitro screening of six anthelmintic plant products against larval Haemonchus contortus with a modified methyl-thiazolyl-tetrazolium reduction assay.

    PubMed

    Hördegen, P; Cabaret, J; Hertzberg, H; Langhans, W; Maurer, V

    2006-11-03

    Because of the increasing anthelmintic resistance and the impact of conventional anthelmintics on the environment, it is important to look for alternative strategies against gastrointestinal nematodes. Phytotherapy could be one of the major options to control these pathologies. Extracts or ingredients of six different plant species were tested against exsheathed infective larvae of Haemonchus contortus using a modified methyl-thiazolyl-tetrazolium (MTT) reduction assay. Pyrantel tartrate was used as reference anthelmintic. Bromelain, the enzyme complex of the stem of Ananas comosus (Bromeliaceae), the ethanolic extracts of seeds of Azadirachta indica (Meliaceae), Caesalpinia crista (Caesalpiniaceae) and Vernonia anthelmintica (Asteraceae), and the ethanolic extracts of the whole plant of Fumaria parviflora (Papaveraceae) and of the fruit of Embelia ribes (Myrsinaceae) showed an anthelmintic efficacy of up to 93%, relative to pyrantel tartrate. Based on these results obtained with larval Haemonchus contortus, the modified MTT reduction assay could be a possible method for testing plant products with anthelmintic properties.

  1. Aluminum structural applications

    SciTech Connect

    Lucas, G.

    1996-05-01

    Extensive research by aluminum producers and automakers in the 1980s resulted in the development of technologies that enable building of aluminum cars that meet and exceed all the expectations of today`s drivers and passengers, yet weigh several hundred pounds less than their steel counterparts. The Acura NSX sports car, the Audi A8, and the Jaguar XJ220 have all been introduced. Ford has built 40 aluminum-intensive automobiles based on the Taurus/Sable for test purposes, and General Motors recently announced an aluminum-structured electric vehicle. The design flexibility that aluminum allows is shown by these examples. Each uses a somewhat different technology that is particularly suited to the vehicle and its market.

  2. Reduction of leaf area and symptom severity as proxies of disease-induced plant mortality: the example of the Cauliflower mosaic virus infecting two Brassicaceae hosts.

    PubMed

    Doumayrou, Juliette; Leblaye, Sophie; Froissart, Rémy; Michalakis, Yannis

    2013-09-01

    Disease induced effects on host survival are important to understand the evolution of parasitic virulence and host resistance/tolerance. Unfortunately, experiments evaluating such effects are in most cases logistically demanding justifying the measurement of survival proxies. For plant hosts commonly used proxies are leaf area and the nature and severity of visual qualitative disease symptoms. In this study we tested whether these traits are indeed correlated to the host mortality rate induced by viral infection. We infected Brassica rapa and Arabidopsis thaliana plants with different natural isolates of Cauliflower mosaic virus (CaMV) and estimated over time the development of symptoms and the relative reduction of leaf area compared to healthy plants and followed plant mortality. We observed that the mortality of infected plants was correlated with the relative reduction of leaf area of both B. rapa and A. thaliana. Measures of mortality were also correlated with the severity of visual qualitative symptoms but the magnitude of the correlations and the time frame at which they were significant depended on the host plant: stronger and earlier correlations were observed on A. thaliana.

  3. Clinical biochemistry of aluminum

    SciTech Connect

    King, S.W.; Savory, J.; Wills, M.R.

    1981-05-01

    Aluminum toxicity has been implicated in the pathogenesis of a number of clinical disorders in patients with chronic renal failure on long-term intermittent hemodialysis treatment. The predominant disorders have been those involving either bone (osteomalacic dialysis osteodystrophy) or brain (dialysis encephalopathy). In nonuremic patients, an increased brain aluminum concentration has been implicated as a neurotoxic agent in the pathogenesis of Alzheimer's disease and was associated with experimental neurofibrillary degeneration in animals. The brain aluminum concentrations of patients dying with the syndrome of dialysis encephalopathy (dialysis dementia) are significantly higher than in dialyzed patients without the syndrome and in nondialyzed patients. Two potential sources for the increased tissue content of aluminum in patients on hemodialysis have been proposed: (1) intestinal absorption from aluminum containing phosphate-binding gels, and (2) transfer across the dialysis membrane from aluminum in the water used to prepare the dialysate. These findings, coupled with our everyday exposure to the ubiquitous occurrence of aluminum in nature, have created concerns over the potential toxicity of this metal.

  4. Enhanced reduction of an azo dye using henna plant biomass as a solid-phase electron donor, carbon source, and redox mediator.

    PubMed

    Huang, Jingang; Chu, Shushan; Chen, Jianjun; Chen, Yi; Xie, Zhengmiao

    2014-06-01

    The multiple effects of henna plant biomass as a source of carbon, electron donor, and redox mediator (RM) on the enhanced bio-reduction of Orange II (AO7) were investigated. The results indicated that the maximum AO7 reduction rate in the culture with henna powder was ∼6-fold that in the sludge control culture lacking henna. On the one hand, AO7 reduction can be advantageously enhanced by the release of available electron donors; on the other hand, the associated lawsone can act as a fixed RM and play a potential role in shuttling electrons from the released electron donors to the final electron acceptor, AO7. The soluble chemical oxygen demand (SCOD) during each experiment and the FTIR spectra suggested that the weakened AO7 reduction along with the retention of henna powder might not be attributed to the lack of fixed lawsone but rather to the insufficiency of electron donors. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Selective reduction of nitric oxides with ammonia using a cellular block catalyst

    SciTech Connect

    M.V. D'yakov; A.I. Kozlov; E.S. Lukin

    2004-03-15

    An aluminum-vanadium cellular block catalyst for selective reduction of nitric oxides with ammonia has been developed. With an average degree of conversion of oxides over 90%, the efficiency of the proposed catalyst is significantly higher than that of industrial catalysts currently used. Such catalyst can be recommended for use in selective plants for purification of waste gases from nitric oxides, which makes it possible to significantly decrease the cost of making a catalyst block.

  6. Aluminum: New challenges in downstream activities

    NASA Astrophysics Data System (ADS)

    Becker, Miklos N.

    1999-11-01

    During its history, aluminum’s attractive features, such as high strength-to-weight ratio, good electrical mass conductivity, and unique corrosion behavior, have led to a spectacular expansion in its use. The role of aluminum in non-aluminum-based materials is also very important; its contribution to the improvement of magnesium and titanium alloys and to highly complex packaging materials are some of the noteworthy examples. Significant cost reductions on the basic metal production level, near-to-shape fabricating methods, and the well-functioning recycling system are also major contributors to aluminum success. Imminent challenges for the industry are the need for products with very close tolerances on a mass fabricating repetitive basis and just-in-time delivery to original-equipment manufacturers and small users through distributors. A significant part of the challenges remains in the applications area, particularly automotive and aerospace.

  7. Link between Aluminum and the Pathogenesis of Alzheimer's Disease: The Integration of the Aluminum and Amyloid Cascade Hypotheses

    PubMed Central

    Kawahara, Masahiro; Kato-Negishi, Midori

    2011-01-01

    Whilst being environmentally abundant, aluminum is not essential for life. On the contrary, aluminum is a widely recognized neurotoxin that inhibits more than 200 biologically important functions and causes various adverse effects in plants, animals, and humans. The relationship between aluminum exposure and neurodegenerative diseases, including dialysis encephalopathy, amyotrophic lateral sclerosis and Parkinsonism dementia in the Kii Peninsula and Guam, and Alzheimer's disease (AD) has been suggested. In particular, the link between aluminum and Alzheimer's disease has been the subject of scientific debate for several decades. However, the complex characteristics of aluminum bioavailability make it difficult to evaluate its toxicity and therefore, the relationship remains to be established. Mounting evidence has suggested that significance of oligomerization of β-amyloid protein and neurotoxicity in the molecular mechanism of AD pathogenesis. Aluminum may play crucial roles as a cross-linker in β-amyloid oligomerization. Here, we review the detailed characteristics of aluminum neurotoxicity based on our own studies and the recent literatures. Our aim is to revisit the link between aluminum and AD and to integrate aluminum and amyloid cascade hypotheses in the context of β-amyloid oligomerization and the interactions with other metals. PMID:21423554

  8. [Effects of aluminum intake on the content of aluminum, iron, zinc and lipid peroxidation in the hippocampus of rats].

    PubMed

    Jia, Y; Zhong, C; Wang, Y; Zhao, R

    2001-05-01

    Effect of long-term exposure to aluminum on the content of aluminum, iron, zinc, copper and the lipid peroxidation in hippocampus was studied. Sprague-Dawley rats were randomly divided into four groups by body weight. Aluminum chloride was added to diet at doses of Al3+ 0, 11.2, 55.9 and 111.9 mg/kg BW for successive 90 days. Neuro-behavioral tests consisted of open field and passive-avoidance conditioning were performed. SOD and GSH-Px activities and MDA levels were detected by spectrophotometry. The values of aluminum, iron, zinc and copper were measured by atomic absorption spectroscopy. The spontaneous motor ability in the open field and the latency of passive avoidance were decreased as compared with the controls. The concentration of aluminum was increased and iron and zinc were decreased copper was not changed significantly; the activities of SOD and GSH-Px were reduced, while the value of MDA was increased in hippocampus. The results suggested that long-term aluminum-exposure could lead to high accumulation of aluminum in hippocampus, which could disturb the normal distribution of iron and zinc, decrease the activities of antioxidase and increase the level of lipid peroxidation. Accumulation of aluminum and accompany with reduction of iron, zinc in hippocampus and oxidative damage to hippocampus might interpret the neurotoxicity of aluminum.

  9. Reduction of inositol (1,4,5)–trisphosphate affects the overall phosphoinositol pathway and leads to modifications in light signalling and secondary metabolism in tomato plants

    PubMed Central

    Alimohammadi, Mohammad; de Silva, Kanishka; Ballu, Clarisse; Ali, Nawab; Khodakovskaya, Mariya V.

    2012-01-01

    The phosphoinositol pathway is one of the major eukaryotic signalling pathways. The metabolite of the phosphoinositol pathway, inositol- (1,4,5) trisphosphate (InsP3), is a regulator of plant responses to a wide variety of stresses, including light, drought, cold, and salinity. It was found that the expression of InsP 5-ptase, the enzyme that hydrolyses InsP3, also dramatically affects the levels of inositol phosphate metabolites and the secondary metabolites in transgenic tomato plants. Tomato plants expressing InsP 5-ptase exhibited a reduction in the levels of several important inositol phosphates, including InsP1, InsP2, InsP3, and InsP4. Reduced levels of inositol phosphates accompanied an increase in the accumulation of phenylpropanoids (rutin, chlorogenic acid) and ascorbic acid (vitamin C) in the transgenic fruits of tomato plants. The enhanced accumulation of these metabolites in transgenic tomato plants was in direct correspondence with the observed up-regulation of the genes that express the key enzymes of ascorbic acid metabolism (myo-inositol oxygenase, MIOX; L-galactono-γ-lactone dehydrogenase, GLDH) and phenylpropanoid metabolism (chalcone synthase, CHS1; cinnamoyl-CoA shikimate/quinate transferase, HCT). To understand the molecular links between the activation of different branches of plant metabolism and InsP3 reduction in tomato fruits, the expression of transcription factors known to be involved in light signalling was analysed by real-time RT-PCR. The expression of LeHY5, SIMYB12, and LeELIP was found to be higher in fruits expressing InsP 5-ptase. These results suggest possible interconnections between phosphoinositol metabolism, light signalling, and secondary metabolism in plants. Our study also revealed the biotechnological potential for the genetic improvement of crop plants by the manipulation of the phosphoinositol pathway. PMID:21994174

  10. Reduction of inositol (1,4,5)-trisphosphate affects the overall phosphoinositol pathway and leads to modifications in light signalling and secondary metabolism in tomato plants.

    PubMed

    Alimohammadi, Mohammad; de Silva, Kanishka; Ballu, Clarisse; Ali, Nawab; Khodakovskaya, Mariya V

    2012-01-01

    The phosphoinositol pathway is one of the major eukaryotic signalling pathways. The metabolite of the phosphoinositol pathway, inositol- (1,4,5) trisphosphate (InsP(3)), is a regulator of plant responses to a wide variety of stresses, including light, drought, cold, and salinity. It was found that the expression of InsP 5-ptase, the enzyme that hydrolyses InsP(3), also dramatically affects the levels of inositol phosphate metabolites and the secondary metabolites in transgenic tomato plants. Tomato plants expressing InsP 5-ptase exhibited a reduction in the levels of several important inositol phosphates, including InsP(1), InsP(2), InsP(3), and InsP(4). Reduced levels of inositol phosphates accompanied an increase in the accumulation of phenylpropanoids (rutin, chlorogenic acid) and ascorbic acid (vitamin C) in the transgenic fruits of tomato plants. The enhanced accumulation of these metabolites in transgenic tomato plants was in direct correspondence with the observed up-regulation of the genes that express the key enzymes of ascorbic acid metabolism (myo-inositol oxygenase, MIOX; L-galactono-γ-lactone dehydrogenase, GLDH) and phenylpropanoid metabolism (chalcone synthase, CHS1; cinnamoyl-CoA shikimate/quinate transferase, HCT). To understand the molecular links between the activation of different branches of plant metabolism and InsP(3) reduction in tomato fruits, the expression of transcription factors known to be involved in light signalling was analysed by real-time RT-PCR. The expression of LeHY5, SIMYB12, and LeELIP was found to be higher in fruits expressing InsP 5-ptase. These results suggest possible interconnections between phosphoinositol metabolism, light signalling, and secondary metabolism in plants. Our study also revealed the biotechnological potential for the genetic improvement of crop plants by the manipulation of the phosphoinositol pathway.

  11. Purifying Aluminum by Vacuum Distillation

    NASA Technical Reports Server (NTRS)

    Du Fresne, E. R.

    1985-01-01

    Proposed method for purifying aluminum employs one-step vacuum distillation. Raw material for process impure aluminum produced in electrolysis of aluminum ore. Impure metal melted in vacuum. Since aluminum has much higher vapor pressure than other constituents, boils off and condenses on nearby cold surfaces in proportions much greater than those of other constituents.

  12. Purifying Aluminum by Vacuum Distillation

    NASA Technical Reports Server (NTRS)

    Du Fresne, E. R.

    1985-01-01

    Proposed method for purifying aluminum employs one-step vacuum distillation. Raw material for process impure aluminum produced in electrolysis of aluminum ore. Impure metal melted in vacuum. Since aluminum has much higher vapor pressure than other constituents, boils off and condenses on nearby cold surfaces in proportions much greater than those of other constituents.

  13. Cast Aluminum Bonding Study

    DTIC Science & Technology

    1988-05-01

    fabricated using P?-’r;est11 bur)ld II19 te(hnll I Oly with 6 cIsL nqs. The cast a lumi num alloy used was A357 . The sur- face preparation was phosphoric acid...from a cast aluminum alloy designated A357 . The bonding surfaces of the adherends were prepared using PAA. One primer and two adhesives considered...System, Cast Aluminum Lap Shear 18 11 Bond Area of 350°F Adhesive System, Cast Aluminum Lap Shear 19 vi LIST OF TABLES TABLE PAGE 1 A357 Chemical

  14. Aluminum Nitride Crystal Growth

    DTIC Science & Technology

    1979-12-01

    UOSR-TR- 80 - 04 2 4EL4- G LEYEL ALUMINUM NITRIDE CRYSTAL GROWTH G.A. Slack FINAL REPORT Contract F49620-78-C-0021 DTIC Period Covered ELECTE I...Laboratory personnel worked on the problem of Aluminum Nitride Heat Sink Crystal Growth for the U.S. Air Force Office of Scientific Research under Contract...Number F44620-76-C-0039. From November 1, 1977 to the present we have worked on Aluminum Nitride and Boron Phosphide Crystal Growth under Contract NUmber

  15. Ion Flux in Roots of Chinese Fir (Cunninghamia lanceolata (Lamb.) Hook) under Aluminum Stress.

    PubMed

    Ma, Zhihui; Huang, Binlong; Xu, Shanshan; Chen, Yu; Cao, Guangqiu; Ding, Guochang; Lin, Sizu

    2016-01-01

    Chinese fir is a tall, fast-growing species that is unique to southern China. In Chinese fir plantations, successive plantings have led to a decline in soil fertility, and aluminum toxicity is thought to be one of the main reasons for this decline. In this study, Non-invasive Micro-test Technology was used to study the effect of aluminum stress on the absorption of 4 different ions in the roots of the Chinese fir clone FS01. The results are as follows: with increased aluminum concentration and longer periods of aluminum stress, the H+ ion flow gradually changed from influx into efflux; there was a large variation in the K+ efflux, which gradually decreased with increasing duration of aluminum stress; and 1 h of aluminum stress uniformly resulted in Ca2+ influx, but it changed from influx to efflux after a longer period of aluminum stress. Changes in the different concentrations of aluminum had the largest influence on Mg2+.

  16. Anodic Oxide Films on Aluminum: Their Significance for Corrosion Protection and Micro- and Nano-Technologies

    NASA Astrophysics Data System (ADS)

    Takahashi, Hideaki; Sakairi, Masatoshi; Kikuchi, Tatsuya

    It was only 120 years ago that humans became able to obtain aluminum metal industrially by applying electricity to reduce bauxite ore. Hence, aluminum is much newer than other metals such as copper, iron, and gold, which have been used since pre-historical times. This is surprising since aluminum comprises 7.56 % of all elements near the surface of the earth, and is found in abundant amounts, next to only oxygen and silicon. The reason why aluminum metal only became available fairly recently is that aluminum has a strong chemical affinity to oxygen, and this prevents reduction of aluminum oxide by chemical reaction with carbon at high temperatures, unlike iron- and copper-oxides. Reduction of aluminum oxide was first realized by H. Davy in 1807, using Voltaic piles, which had been invented in 1800 by the Italian scientist, A. Volta.

  17. Potential of Chilopsis Linearis for Gold Phytomining: Using XAS to Determine Gold Reduction And Nanoparticle Formation Within Plant Tissues

    SciTech Connect

    E, Rodriguez; Parsons, J.G.; Peralta-Videa, J.R.; Cruz-Jiminez, G.; Romera-Gonzalez, J.; Sanchez-Salcido, B.E.; Saupe, G.B.; Duarte-Gardea, M.; Gardea-Torresdey, J.L.

    2009-06-04

    This study reports on the capability of the desert plant Chilopsis linearis (Cav.) Sweet (desert willow) to uptake gold (Au) from gold-enriched media at different plant-growth stages. Plants were exposed to 20, 40, 80, 160, and 320 mg Au L{sup -1} in agar-based growing media for 13, 18, 23, and 35 d. The Au content and oxidation state of Au in the plants were determined using an inductively coupled plasma/optical emission spectrometer (ICP/OES) and X-ray absorption spectroscopy (XAS), respectively. Gold concentrations ranging from 20 to 80 mg Au L{sup -1} did not significantly affect Chilopsis linearis plant growth. The concentration of gold in the plants increased as the age of the plant increased. The Au concentrations in leaves for the 20, 40, 80, and 160 mg Au L{sup -1} treatments were 32, 60, 62, and 179 mg Au kg{sup -1} dry weight mass, respectively, demonstrating the gold uptake capability of desert willow. The XAS data indicated that desert willow produced gold nanoparticles within plant tissues. Plants exposed to 160 mg Au L{sup -1} formed nanoparticles that averaged approximately 8, 35, and 18 in root, stem, and leaves, respectively. It was observed that the average size of the Au nanoparticles formed by the plants is related to the total Au concentration in tissues and their location in the plant.

  18. A reduction of sucrose phosphate synthase (SPS) activity affects sucrose/starch ratio in leaves but does not inhibit normal plant growth in rice.

    PubMed

    Hashida, Yoichi; Hirose, Tatsuro; Okamura, Masaki; Hibara, Ken-Ichiro; Ohsugi, Ryu; Aoki, Naohiro

    2016-12-01

    Sucrose phosphate synthase (SPS) has been shown to mediate sucrose/starch ratio in plant leaves through studies of 'starch leaf' species that mainly accumulate starch in their leaves. However, the contribution of SPS to sucrose/starch ratio in rice leaves, which mainly accumulate sucrose (i.e., 'sugar leaf'), has not been confirmed due to inconsistencies in the results of previous studies. In this study, we analyzed mutant lines with reduced SPS activity, which were generated using Tos17 insertion, RNAi, and the CRISPR/Cas9 system. The knockdown and knockout mutants of OsSPS1 showed a 29-46% reduction in SPS activity in the leaves, but the carbohydrate content in the leaves and plant growth were not significantly different from those of wild-type plants. In a double knockout mutant of OsSPS1 and OsSPS11 (sps1/sps11), an 84% reduction in leaf SPS activity resulted in higher starch accumulation in the leaves than in the wild-type leaves. However, the sps1/sps11 plants grew normally, which is in contrast to the inhibited growth of SPS mutants of Arabidopsis thaliana, a typical starch leaf plant. These results suggest that SPS has a smaller effect on the sucrose/starch ratio in leaves and growth of rice than on starch leaf species. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  19. Brazing of dispersion-strengthened aluminum

    SciTech Connect

    Bjoerneklett, B.; Grong, O.; Anisdahl, L.; Hellum, E.; Sande, V.

    1996-03-01

    In recent years, the use of rapid solidification powder metallurgy has made it possible to develop a new family of aluminum alloys exhibiting unique properties. One of these materials, dispersion-strengthened (DS) aluminum, is currently being produced for commercial purposes at Raufoss Technology AS, Norway. Dispersion-strengthened aluminum derives its high strength from nanoscale AlN particles embedded in an aluminum matrix. DS Al is expected to be well suited as construction material for high-temperature applications where weight reductions are of particular concern. The present investigation has focused on the wetting behavior of DS aluminum under conditions applicable to brazing. The results from the Sessile drop experiments show that a eutectic Al-Si brazing alloy will completely wet the base metal both under high-vacuum conditions and in controlled argon atmospheres, provided that the partial pressure of oxygen is sufficiently low. The main problem appears to be the stability of the matrix grain structure. In general, the process of grain erosion and coarsening can be controlled by restricting the supply of the brazing alloy so that only a small metal volume is exposed to erosion. In addition, there is a great potential for reducing the thermodynamic driving force of the erosion reaction by proper adjustments of the brazing alloy composition and/or the brazing temperature. Sill, grain boundary liquidation may be a problem which, in turn, may require additions of surface active elements to the filler metal to control the wetting behavior.

  20. Compensation effect of winter wheat grain yield reduction under straw mulching in wide-precision planting in the North China Plain.

    PubMed

    Liu, Xinhui; Ren, Yujie; Gao, Chao; Yan, Zhenxing; Li, Quanqi

    2017-03-16

    Climate change and the growing demand for food security force growers to identify ways both to improve food production and to reduce agricultural carbon emissions. Although straw mulching is known to decrease CO2 emissions, winter wheat grain yield in the North China Plain was declined under straw mulching. In an effort to determine the most effective way to increase winter wheat yield under straw mulching, a field experiment was conducted using two planting patterns (wide-precision planting and conventional-cultivation planting) and two straw mulching rates (0 and 0.6 kg/m(2)). The results showed the wide-precision planting/non-mulching treatment significantly increased the leaf area index more than the other three treatments at the early growth stage. This treatment improved aboveground dry matter accumulation and was conducive to increased spike weight in the late growth stage. By contrast, straw mulching significantly reduced winter wheat grain yields by lowering both spike number and 1000-grain weight at the mature plant stage. In the wide-precision planting/mulching treatment, a significantly increased spike number compensated for grain yield losses. The results support the idea that wide-precision planting combined with straw mulching has the potential to decrease the winter wheat grain yield reduction previously observed with straw mulching in the North China Plain.

  1. Occurrence and reduction of human viruses, F-specific RNA coliphage genogroups and microbial indicators at a full-scale wastewater treatment plant in Japan.

    PubMed

    Hata, A; Kitajima, M; Katayama, H

    2013-02-01

    To evaluate and compare the reductions of human viruses and F-specific coliphages in a full-scale wastewater treatment plant based on the quantitative PCR (qPCR) and plate count assays. A total of 24 water samples were collected from four locations at the plant, and the relative abundance of human viruses and F-RNA phage genogroups were determined by qPCR. Of the 10 types of viruses tested, enteric adenoviruses were the most prevalent in both influent and effluent wastewater samples. Of the different treatment steps, the activated sludge process was most effective in reducing the microbial loads. Viruses and F-RNA phages showed variable reduction; among them, GI and GIII F-RNA phages showed the lowest and the highest reduction, respectively. Ten types of viruses were present in wastewater that is discharged into public water bodies after treatment. The variability in reduction for the different virus types demonstrates that selection of adequate viral indicators is important for evaluating the efficacy of wastewater treatment and ensuring the water safety. Our comprehensive analyses of the occurrence and reduction of viruses and indicators can contribute to the future establishment of appropriate viral indicators to evaluate the efficacy of wastewater treatment. © 2012 The Society for Applied Microbiology.

  2. Minimizing residual aluminum concentration in treated water by tailoring properties of polyaluminum coagulants.

    PubMed

    Kimura, Masaoki; Matsui, Yoshihiko; Kondo, Kenta; Ishikawa, Tairyo B; Matsushita, Taku; Shirasaki, Nobutaka

    2013-04-15

    Aluminum coagulants are widely used in water treatment plants to remove turbidity and dissolved substances. However, because high aluminum concentrations in treated water are associated with increased turbidity and because aluminum exerts undeniable human health effects, its concentration should be controlled in water treatment plants, especially in plants that use aluminum coagulants. In this study, the effect of polyaluminum chloride (PACl) coagulant characteristics on dissolved residual aluminum concentrations after coagulation and filtration was investigated. The dissolved residual aluminum concentrations at a given coagulation pH differed among the PACls tested. Very-high-basicity PACl yielded low dissolved residual aluminum concentrations and higher natural organic matter (NOM) removal. The low residual aluminum concentrations were related to the low content of monomeric aluminum (Ala) in the PACl. Polymeric (Alb)/colloidal (Alc) ratio in PACl did not greatly influence residual aluminum concentration. The presence of sulfate in PACl contributed to lower residual aluminum concentration only when coagulation was performed at around pH 6.5 or lower. At a wide pH range (6.5-8.5), residual aluminum concentrations <0.02 mg/L were attained by tailoring PACl properties (Ala percentage ≤0.5%, basicity ≥85%). The dissolved residual aluminum concentrations did not increase with increasing the dosage of high-basicity PACl, but did increase with increasing the dosage of normal-basicity PACl. We inferred that increasing the basicity of PACl afforded lower dissolved residual aluminum concentrations partly because the high-basicity PACls could have a small percentage of Ala, which tends to form soluble aluminum-NOM complexes with molecular weights of 100 kDa-0.45 μm. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Walnut Hulls Clean Aluminum

    NASA Technical Reports Server (NTRS)

    Colberg, W. R.; Gordon, G. H.; Jackson, C. H.

    1984-01-01

    Hulls inflict minimal substrate damage. Walnut hulls found to be best abrasive for cleaning aluminum surfaces prior to painting. Samples blasted with walnut hulls showed no compressive stress of surface.

  4. Corrosion Inhibitors for Aluminum.

    ERIC Educational Resources Information Center

    Muller, Bodo

    1995-01-01

    Describes a simple and reliable test method used to investigate the corrosion-inhibiting effects of various chelating agents on aluminum pigments in aqueous alkaline media. The experiments that are presented require no complicated or expensive electronic equipment. (DDR)

  5. Corrosion Inhibitors for Aluminum.

    ERIC Educational Resources Information Center

    Muller, Bodo

    1995-01-01

    Describes a simple and reliable test method used to investigate the corrosion-inhibiting effects of various chelating agents on aluminum pigments in aqueous alkaline media. The experiments that are presented require no complicated or expensive electronic equipment. (DDR)

  6. CORROSION PROTECTION OF ALUMINUM

    DOEpatents

    Dalrymple, R.S.; Nelson, W.B.

    1963-07-01

    Treatment of aluminum-base metal surfaces in an autoclave with an aqueous chromic acid solution of 0.5 to 3% by weight and of pH below 2 for 20 to 50 hrs at 160 to 180 deg C produces an extremely corrosion-resistant aluminum oxidechromium film on the surface. A chromic acid concentration of 1 to 2% and a pH of about 1 are preferred. (D.C.W.)

  7. Corrosion Protection of Aluminum

    DOEpatents

    Dalrymple, R. S.; Nelson, W. B.

    1963-07-01

    Treatment of aluminum-base metal surfaces in an autoclave with an aqueous chromic acid solution of 0.5 to 3% by weight and of pH below 2 for 20 to 50 hrs at 160 to 180 deg C produces an extremely corrosion-resistant aluminum oxidechromium film on the surface. A chromic acid concentration of 1 to 2% and a pH of about 1 are preferred.

  8. Aluminum powder applications

    SciTech Connect

    Gurganus, T.B.

    1995-08-01

    Aluminum powders have physical and metallurgical characteristics related to their method of manufacture that make them extremely important in a variety of applications. They can propel rockets, improve personal hygiene, increase computer reliability, refine exotic alloys, and reduce weight in the family sedan or the newest Air Force fighter. Powders formed into parts for structural and non-structural applications hold the key to some of the most exciting new developments in the aluminum future.

  9. A case study of the relative effects of power plant nitrogen oxides and sulfur dioxide emission reductions on atmospheric nitrogen deposition.

    PubMed

    Vijayaraghavan, Krish; Seigneur, Christian; Bronson, Rochelle; Chen, Shu-Yun; Karamchandani, Prakash; Walters, Justin T; Jansen, John J; Brandmeyer, Jo Ellen; Knipping, Eladio M

    2010-03-01

    The contrasting effects of point source nitrogen oxides (NOx) and sulfur dioxide (SO2) air emission reductions on regional atmospheric nitrogen deposition are analyzed for the case study of a coal-fired power plant in the southeastern United States. The effect of potential emission reductions at the plant on nitrogen deposition to Escambia Bay and its watershed on the Florida-Alabama border is simulated using the three-dimensional Eulerian Community Multiscale Air Quality (CMAQ) model. A method to quantify the relative and individual effects of NOx versus SO2 controls on nitrogen deposition using air quality modeling results obtained from the simultaneous application of NOx and SO2 emission controls is presented and discussed using the results from CMAQ simulations conducted with NOx-only and SO2-only emission reductions; the method applies only to cases in which ambient inorganic nitrate is present mostly in the gas phase; that is, in the form of gaseous nitric acid (HNO3). In such instances, the individual effects of NOx and SO2 controls on nitrogen deposition can be approximated by the effects of combined NOx + SO2 controls on the deposition of NOy, (the sum of oxidized nitrogen species) and reduced nitrogen species (NHx), respectively. The benefit of controls at the plant in terms of the decrease in nitrogen deposition to Escambia Bay and watershed is less than 6% of the overall benefit due to regional Clean Air Interstate Rule (CAIR) controls.

  10. Novel aqueous dual-channel aluminum-hydrogen peroxide battery

    NASA Astrophysics Data System (ADS)

    Marsh, Catherine; Licht, Stuart

    1994-06-01

    A dual-channel aluminum hydrogen peroxide battery is introduced with an open-circuit voltage of 1.9 volts, polarization losses of 0.9 mV cm(exp 2) mA(exp -1), and power densities of 1 W/cm(exp 2). Catholyte and anolyte cell compartments are separated by an Ir/Pd modified porous nickel cathode. Separation of catholyte and anolyte chambers prevents hydrogen peroxide poisoning of the aluminum anode. The battery is expressed by aluminum oxidation and aqueous solution phase hydrogen peroxide reduction for an overall battery discharge consisting of 2Al + 3H2O2 + 2OH(-) yields 2AlO2(-) + 4H2O E = 2.3 V. The search for electrical propulsion sources which fit the requirements for electrically powered vehicles has blurred the standard characteristics associated with electrochemical storage systems. Presently, electrochemical systems comprised of mechanically rechargeable primary batteries, secondary batteries, and fuel cells are candidates for electrochemical propulsion sources. While important advances in energy and power density continue for nonaqueous and molten electrolytes, aqueous electrolyte batteries often have an advantage in simplicity, conductivity, cost effectiveness, and environmental impact. Systems coupling aluminum anodes and aqueous electrolytes have been investigated. These systems include: aluminum/silver oxide, aluminum/manganese dioxide, aluminum air, aluminum/hydrogen peroxide aqueous batteries, and the recently introduced aluminum/ferricyanide and aluminum sulfur aqueous batteries. Conventional aqueous systems such as the nickel cadmium and lead-acid batteries are characterized by their relatively low energy densities and adverse environmental impact. Other systems have substantially higher theoretical energy capacities. While aluminum-silver oxide has demonstrated the highest steady-state power density, its high cost is an impediment for widespread utilization for electric propulsion.

  11. Catalytic reduction of nitrate in secondary effluent of wastewater treatment plants by Fe(0) and Pd-Cu/γ-Al2O3.

    PubMed

    Yun, Yupan; Li, Zifu; Chen, Yi-Hung; Saino, Mayiani; Cheng, Shikun; Zheng, Lei

    2016-01-01

    Total nitrogen, in which NO3(-) is dominant in the effluent of most wastewater treatment plants, cannot meet the requirements of the Chinese wastewater discharge standard (<15 mg/L), making nitrate (NO3(-)) elimination attract considerable attention. In this study, reductant iron (Fe(0)) and γ-Al2O3 supported palladium-copper bimetallic catalysts (Pd-Cu/γ-Al2O3) were innovatively used for the chemical catalytic reduction of nitrate in wastewater. A series of specific operational conditions (such as mass ratio of Pd:Cu, catalyst amounts, reaction time and pH of solution) were optimized for nitrate reduction in the artificial solution, and then the selected optimal conditions were further applied for investigating the nitrate elimination of secondary effluent of a wastewater treatment plant in Beijing, China. Results indicated that a better catalytic performance (74% of nitrate removal and 62% of N2 selectivity) could be obtained under the optimal condition: 5 g/L Fe(0), 3:1 mass ratio (Pd:Cu), 4 g/L catalyst, 2 h reaction time and pH 5.1. It is noteworthy to point out that nitrogen gas (N2) predominated in the byproducts without another system to treat ammonium and nitrite. Therefore, the chemical catalytic reduction combining Fe(0) with Pd-Cu/γ-Al2O3 could be regarded as a better alternative for nitrate removal in wastewater treatment.

  12. Aluminum, parathyroid hormone, and osteomalacia

    SciTech Connect

    Burnatowska-Hledin, M.A.; Kaiser, L.; Mayor, G.H.

    1983-01-01

    Aluminum exposure in man is unavoidable. The occurrence of dialysis dementia, vitamin D-resistant osteomalacia, and hypochromic microcytic anemia in dialysis patients underscores the potential for aluminum toxicity. Although exposure via dialysate and hyperalimentation leads to significant tissue aluminum accumulation, the ubiquitous occurrence of aluminum and the severe pathology associated with large aluminum burdens suggest that smaller exposures via the gastrointestinal tract and lungs could represent an important, though largely unrecognized, public health problem. It is clear that some aluminum absorption occurs with the ingestion of small amounts of aluminum in the diet and medicines, and even greater aluminum absorption is seen in individuals consuming large amounts of aluminum present in antacids. Aluminum absorption is enhanced in the presence of elevated circulating parathyroid hormone. In addition, elevated PTH leads to the preferential deposition of aluminum in brain and bone. Consequently, PTH is likely to be involved in the pathogenesis of toxicities in those organs. PTH excess also seems to lead to the deposition of aluminum in the parathyroid gland. The in vitro demonstration that aluminum inhibits parathyroid hormone release is consistent with the findings of a euparathyroid state in dialysis patients with aluminum related vitamin D-resistant osteomalacia. Nevertheless, it seems likely that hyperparathyroidism is at least initially involved in the pathogenesis of aluminum neurotoxicity and osteomalacia; the increases in tissue aluminum stores are followed by suppression of parathyroid hormone release, which is required for the evolution of osteomalacia. Impaired renal function is not a prerequisite for increased tissue aluminum burdens, nor for aluminum-related organ toxicity. Consequently, it is likely that these diseases will be observed in populations other than those with chronic renal disease.

  13. Recent Advances on the Molecular Basis of Crop Aluminum Resistance

    USDA-ARS?s Scientific Manuscript database

    The considerable genetic variability for aluminum (Al) resistance within many crop plant species has been utilized by plant breeders for a number of years to enhance Al resistance. But beyond this, genetic variability in Al resistance has been an excellent experimental resource that is being mined b...

  14. Transcriptional regulation in maize roots under aluminum stress

    USDA-ARS?s Scientific Manuscript database

    Aluminum toxicity in acid soils is a major factor limiting crop yields. The importance of this topic is underscored by the intensive research focused on the mechanisms underlying plant Al tolerance. A major tolerance mechanism identified in several plant species is the exclusion of Al from the root ...

  15. Reduction of interleukin-1β induced matrix metalloproteinase-3 release by extracts of six plants: inhibitory screening of 35 traditional medicinal plants.

    PubMed

    Ra, Jehyeon; Chung, Joo-Ho; Lee, Heyjung; Kim, Jinju

    2011-09-01

    Rheumatoid arthritis (RA) is a chronic inflammatory joint disease associated with matrix metalloproteinase (MMP)-3, leading to destruction of the cartilage. The objective of this study was to investigate and discuss the suitability of the 35 medicinal plants as therapeutic candidates to treat RA. Fibroblast-like synoviocytes (FLSs), derived from patients with RA, were adjusted to 2 × 10(6) cells/mL in a 24-well plate and pretreated with the distilled water extracts of the 35 plants (1, 10, and 100 µg/mL) for 1 h followed by interleukin-1β (IL-1β) (1 ng/mL) for 24 h. The concentration of MMP-3 was then determined using a Duoset ELISA Kit. The six plants (Artemisiae Capillaris Herba, AC; Bambusae Caulis In Taeniam, BC; Cassiae Semen, CS; Corni Fructus, CF; Leonuri Herba, LH; Schizonepetae Spica, SS) showed no toxicity, including MMP-3. The MMP-3 level was increased by 3.38-fold (212.23 μg/mL) in IL-1β-stimulated FLSs. The IL-1β-induced MMP-3 level was significantly and dose-dependently reduced by >50% by the six plants (P < 0.01: at 100  μg/ mL of CS and LH, P < 0.001: at 10 μg/mL of all plants, and at 100 μg/mL of AC, BC, CF, and SS). This is the first study on the MMP-3 inhibitory effect of the examined plants in FLSs isolated from RA patients. From our original research, the six candidate plants were identified.

  16. Fatal aluminum phosphide poisoning.

    PubMed

    Anger, F; Paysant, F; Brousse, F; Le Normand, I; Develay, P; Gaillard, Y; Baert, A; Le Gueut, M A; Pepin, G; Anger, J P

    2000-03-01

    A 39-year-old man committed suicide by ingestion of aluminum phosphide, a potent mole pesticide, which was available at the victim's workplace. The judicial authority ordered an autopsy, which ruled out any other cause of death. The victim was discovered 10 days after the ingestion of the pesticide. When aluminum phosphide comes into contact with humidity, it releases large quantities of hydrogen phosphine (PH3), a very toxic gas. Macroscopic examination during the autopsy revealed a very important asphyxia syndrome with major visceral congestion. Blood, urine, liver, kidney, adrenal, and heart samples were analyzed. Phosphine gas was absent in the blood and urine but present in the brain (94 mL/g), the liver (24 mL/g), and the kidneys (41 mL/g). High levels of phosphorus were found in the blood (76.3 mg/L) and liver (8.22 mg/g). Aluminum concentrations were very high in the blood (1.54 mg/L), brain (36 microg/g), and liver (75 microg/g) compared to the usual published values. Microscopic examination revealed congestion of all the organs studied and obvious asphyxia lesions in the pulmonary parenchyma. All these results confirmed a diagnosis of poisoning by aluminum phosphide. This report points out that this type of poisoning is rare and that hydrogen phosphine is very toxic. The phosphorus and aluminum concentrations observed and their distribution in the different viscera are discussed in relation to data in the literature.

  17. Benefits to rare plants and highway safety from annual population reductions of a "native invader," white-tailed deer, in a Chicago-area woodland.

    PubMed

    Engeman, Richard M; Guerrant, Travis; Dunn, Glen; Beckerman, Scott F; Anchor, Chris

    2014-01-01

    Overabundant white-tailed deer are one of the most serious threats to woodland plant communities in the Chicago area. Moreover, the abundant deer in a highly populated area causes economic harm and poses hazards to human safety through collisions with vehicles. The artificial conditions causing the overabundance and resulting consequences qualify the white-tailed deer in the Chicago area to be considered as "native invaders". We examined the benefits of culling deer at a Chicago-area woodland preserve by comparing browse rates on four endangered plant species from years before culling began with years with culling. We also examined deer-vehicle collision and traffic flow rates on area roads from years before culling began and years with culling to assess whether population reductions may have benefited road safety in the area. All four endangered plant species (three orchid species and sweet fern) had lower browse rates in years with culls, although the decreased browsing rates were statistically distinguishable for only two of the species (grass pink orchid and sweet fern). After first verifying that traffic flow rates did not decrease from pre-cull years to years with culls, we analyzed the Illinois Department of Transportation data from area roads based on deer-vehicle collisions causing >US$500 in damage and showed a one-third reduction in deer-vehicle collisions. An economic analysis showed a cost savings during the cull years of US$0.6 million for reducing browsing to just these four monitored plant species and the reduction in deer-vehicle collisions.

  18. Qualitative Exploration of the Potential Causes of Serious Reduction in Availability of Medicinal Plants in the Qinghai-Tibetan High Plateau.

    PubMed

    Cuomu, Mingji

    2013-03-01

    In the last ten years, there has been a dramatic reduction in medicinal plants in Tibet. This situation has attracted the attention of many researchers from different professional backgrounds, yet very few documents have been published on the general theoretical context and the actual process of herb collection as it occurs at different levels in clinics in Tibet. This article begins with a systematic review of the general principles of medicinal plant collection methods as set out in the ancient traditional medical system. Because the demand for plants is generated by the need to make Tibetan medicines, it is necessary to consider the original context of Tibetan medicine to understand pharmacological needs and the principles behind collecting medicinal plants to develop a strategy that might guarantee sustainable development of the plant supply. After considering the wider context of this study, the article presents research mainly based on case studies with the intention of understanding different stakeholders' experiences and social relationships in the contemporary herb collection process in order to discover behavioral patterns within the dynamic social roles involved in this process as these inform policy formation and to seek to promote appropriate methods in the future.

  19. Qualitative Exploration of the Potential Causes of Serious Reduction in Availability of Medicinal Plants in the Qinghai-Tibetan High Plateau

    PubMed Central

    Cuomu, Mingji

    2014-01-01

    In the last ten years, there has been a dramatic reduction in medicinal plants in Tibet. This situation has attracted the attention of many researchers from different professional backgrounds, yet very few documents have been published on the general theoretical context and the actual process of herb collection as it occurs at different levels in clinics in Tibet. This article begins with a systematic review of the general principles of medicinal plant collection methods as set out in the ancient traditional medical system. Because the demand for plants is generated by the need to make Tibetan medicines, it is necessary to consider the original context of Tibetan medicine to understand pharmacological needs and the principles behind collecting medicinal plants to develop a strategy that might guarantee sustainable development of the plant supply. After considering the wider context of this study, the article presents research mainly based on case studies with the intention of understanding different stakeholders’ experiences and social relationships in the contemporary herb collection process in order to discover behavioral patterns within the dynamic social roles involved in this process as these inform policy formation and to seek to promote appropriate methods in the future. PMID:25478035

  20. Interactions of aluminum with forest soils and vegetation: Implications for acid deposition

    SciTech Connect

    Maynard, A.A.

    1989-01-01

    Recent evidence suggests that an important ecological consequence of acidic deposition is increased aluminum mobilization. There is concern that increased aluminum activity may produce toxic effects in forested ecosystems. My studies were concerned with the behavior of pedogenic and added aluminum in soils derived from chemically different parent material. Soil aluminum was related to the aluminum content of the vegetation found growing in the soils. In addition, aluminum levels of forest litter was compared to levels determined 40 years ago. Field, greenhouse, and laboratory investigations were conducted in which the effects of aluminum concentration on germination and early growth was determined. Soils were then used in greenhouse and laboratory studies to establish patterns of soil and plant aluminum behavior with implications to acid deposition. Results show that the amount of aluminum extracted was related to the pH value of the extracting solution and to the chemical characteristics of the soil. Some acid rain solutions extracted measurable amounts of aluminum from selected primary minerals. Germination and early growth of Pinus radiata was controlled by levels of aluminum in the soil or in solution. Field studies indicated that most forest species were sensitive to rising levels of aluminum in the soil. In general, ferns and fern allies were less sensitive to very high levels of aluminum in the soil, continuing to grow when more advanced dicots have disappeared. Aluminum tissue levels of all species were related to the concentration of aluminum in the soil as was the reappearance of species. Aluminum levels in leaf litter have risen at least 50% in the last 40 years. These values were consistent over 3 years. The implications to acid deposition were discussed.

  1. Studies on the reduction kinetics of hematite iron ore pellets with noncoking coals for sponge iron plants

    SciTech Connect

    Kumar, M.; Mohapatra, P.; Patel, S.K.

    2009-07-01

    In the present investigation, fired pellets were made by mixing hematite iron ore fines of -100, -16+18, and -8+10 mesh size in different ratios and studies on their reduction kinetics in Lakhanpur, Orient OC-2 and Belpahar coals were carried out at temperatures ranging from 850{sup o}C to 1000{sup o}C with a view toward promoting the massive utilization of fines in ironmaking. The rate of reduction in all the fired iron ore pellets increased markedly with an increase in temperature up to 1000{sup o}C, and it was more intense in the first 30min. The values of activation energy, calculated from integral and differential approaches, for the reduction of fired pellets (prepared from iron ore fines of -100 mesh size) in coals were found to be in the range 131-148 and 130-181 kJ mol{sup -1} (for =0.2 to 0.8), indicating the process is controlled by a carbon gasification reaction. The addition of selected larger size particles in the matrix of -100 mesh size fines up to the extent studied decreased the activation energy and slightly increased the reduction rates of resultant fired pellets. In comparison to coal, the reduction of fired pellets in char was characterized by significantly lower reduction rates and higher activation energy.

  2. Effect of dissimilatory iron and sulfate reduction on Arsenic dynamics in the wetland rhizosphere and its bioaccumulation in plants

    NASA Astrophysics Data System (ADS)

    Zhang, Zheyun; Moon, Hee Sun; Myneni, Satish; Jaffe, Peter

    2015-04-01

    Arsenic (As) pollution in water soil and sediments is of worldwide concern due to its ecological toxicity and chronic effects on human health. Wetlands are at the interface between ground and surface waters and because of their unique biogeochemical dynamics could be promising location for arsenic immobilization. However, the nature of biogeochemical reactions of As in wetlands are complex and not well understood. The dynamics of As in wetland sediments are closely linked to the redox cycling of Fe and S, both of which are affected by water-table fluctuations and wetland plants activity that are typical in such environments. Little is not known about redox cycling of Fe or S and their effects on As speciation, biogeochemical dynamics, and bioaccumulation in the wetland rhizosphere and plants. To gain further insights into these processes, twelve mesocosms were set up and planted with wetland plants (Scirpus actus), six were submerged in a tray (reactor) with ~ 170 mM SO4-2 and six in a tray with ~ 350 uM SO4-2 and two levels of ferrihydrite in the soil for each SO4-2 treatment. Each mesocosm was sealed and the only contact with the solution in the reactor was via the surface of the mesocosm. The mesocosms were run for 1.5 months to establish the plants, after which 50μM Na2HAsO4·7H2O was added to the reactors. Water in the reactors was constantly recirculated to make the solution homogeneous. The reactors were run for 4 months and monitored regularly for dissolved species, and were then dismantled. Results show that the presence of plants, high Fe, and high SO42- levels enhanced As sequestration in the soil. We hypothesize that the reason for this compounding effect is that plants release easily biodegradable organic carbon, which is used by microorganism to reduce ferrihydrite and SO42- to generate FeS or FeS2. More As is then sequestrated via sorption or co-precipitation on FeS or FeS2. Analysis of As in plant tissue showed that As uptake by Scirpus actus was

  3. Elevated temperature aluminum alloys

    NASA Technical Reports Server (NTRS)

    Meschter, Peter (Inventor); Lederich, Richard J. (Inventor); O'Neal, James E. (Inventor)

    1989-01-01

    Three aluminum-lithium alloys are provided for high performance aircraft structures and engines. All three alloys contain 3 wt % copper, 2 wt % lithium, 1 wt % magnesium, and 0.2 wt % zirconium. Alloy 1 has no further alloying elements. Alloy 2 has the addition of 1 wt % iron and 1 wt % nickel. Alloy 3 has the addition of 1.6 wt % chromium to the shared alloy composition of the three alloys. The balance of the three alloys, except for incidentql impurities, is aluminum. These alloys have low densities and improved strengths at temperatures up to 260.degree. C. for long periods of time.

  4. The Nondestructive Determination of the Aluminum Content in Pressed Skulls of Aluminum Dross

    NASA Astrophysics Data System (ADS)

    Kevorkijan, Varuzan; Škapin, Srečo Davor; Kovačec, Uroš

    2013-02-01

    prediction of the amount of free aluminum in pressed skulls w Al, based on nondestructive measurement of the density ρ of the pressed skulls. The pressed skulls density is measured by a fully automatic gas displacement pyknometer with a working volume large enough to enable the insertion of the whole pressed skull sample. An additional integral part of this methodology is the set of experimentally determined linear graphs w Al- ρ, plotted in advance for all classes of pressed skulls existing in the plant, from the experimentally collected data on pressed skulls density and aluminum recovery by melting. After selecting the proper graph w Al- ρ, which is usually performed on an aluminum alloy basis, the pyknometric measured density of the pressed skulls can be routinely related to the aluminum content sought, within a relative error of ±5%.

  5. PROCESS FOR REMOVING ALUMINUM COATINGS

    DOEpatents

    Flox, J.

    1959-07-01

    A process is presented for removing aluminum jackets or cans from uranium slugs. This is accomplished by immersing the aluminum coated uranium slugs in an aqueous solution of 9 to 20% sodium hydroxide and 35 to 12% sodium nitrate to selectively dissolve the aluminum coating, the amount of solution being such as to obtain a molar ratio of sodium hydroxide to aluminum of at least

  6. Aluminum Alloy 7068 Mechanical Characterization

    DTIC Science & Technology

    2009-08-01

    strength of 99 ksi (2). The commonly specified material properties for extruded 7068 aluminum are shown in table 1, along with 7050 and 7075 aluminum ...alloys for comparison (3). Table 1. Mechanical property comparison of high-strength aluminum alloys. Property Alloy 7068 7075 7050 Elastic... Aluminum Alloy 7068 Mechanical Characterization by Michael Minnicino, David Gray, and Paul Moy ARL-TR-4913 August 2009

  7. Reductions of plant cover induced by sheep grazing change the above-belowground partition and chemistry of organic C stocks in arid rangelands of Patagonian Monte, Argentina.

    PubMed

    Larreguy, C; Carrera, A L; Bertiller, M B

    2017-09-01

    The objective of this study was to estimate the size and chemical quality of the total organic C stock and its partition between above-belowground plant parts and soil at sites with different plant cover induced by sheep grazing in the arid Patagonian Monte. This study was conducted at six representative sites with increasing signs of canopy disturbance attributed to grazing pressure. We used faeces density as a proxy of grazing pressure at each site. We assessed the total plant cover, shrub and perennial grass cover, total standing aboveground biomass (AGB), litter mass and belowground biomass (BGB) at each site. We further estimated the content of organic C, lignin and soluble phenols in plant compartments and the content of organic C, organic C in humic substances (recalcitrant C) and water soluble C (labile C) in soil at each site. Total plant cover was significantly related to grazing pressure. Standing AGB and litter mass decreased with increasing canopy disturbance while BGB did not vary across sites. Total organic C stock and the organic C stock in standing AGB increased with increasing total plant, shrub, and perennial grass cover. The organic C stock in litter mass increased with increasing total plant and shrub cover, while the organic C stock in BGB did not vary across sites. Lignin content in plant compartments increased with increasing total and shrub cover, while soluble phenols content did not change across sites. The organic C stock and the water soluble C content in soil were positively associated with perennial grass cover. Changes in total plant cover induced by grazing pressure negatively affected the size of the total organic C stock, having minor impact on the size of belowground than aboveground components. The reduction of perennial grass cover was reflected in decreasing chemical quality of the organic C stock in soil. Accordingly, plant managerial strategies should not only be focused on the amount of organic C sequestered but also on the

  8. ALUMINUM AND CHROMIUM LEACHING WORKSHOP WHITEPAPER

    SciTech Connect

    McCabe, D; Jeff Pike, J; Bill Wilmarth, B

    2007-04-25

    A workshop was held on January 23-24, 2007 to discuss the status of processes to leach constituents from High Level Waste (HLW) sludges at the Hanford and Savannah River Sites. The objective of the workshop was to examine the needs and requirements for the HLW flowsheet for each site, discuss the status of knowledge of the leaching processes, communicate the research plans, and identify opportunities for synergy to address knowledge gaps. The purpose of leaching of non-radioactive constituents from the sludge waste is to reduce the burden of material that must be vitrified in the HLW melter systems, resulting in reduced HLW glass waste volume, reduced disposal costs, shorter process schedules, and higher facility throughput rates. The leaching process is estimated to reduce the operating life cycle of SRS by seven years and decrease the number of HLW canisters to be disposed in the Repository by 1000 [Gillam et al., 2006]. Comparably at Hanford, the aluminum and chromium leaching processes are estimated to reduce the operating life cycle of the Waste Treatment Plant by 20 years and decrease the number of canisters to the Repository by 15,000-30,000 [Gilbert, 2007]. These leaching processes will save the Department of Energy (DOE) billions of dollars in clean up and disposal costs. The primary constituents targeted for removal by leaching are aluminum and chromium. It is desirable to have some aluminum in glass to improve its durability; however, too much aluminum can increase the sludge viscosity, glass viscosity, and reduce overall process throughput. Chromium leaching is necessary to prevent formation of crystalline compounds in the glass, but is only needed at Hanford because of differences in the sludge waste chemistry at the two sites. Improving glass formulations to increase tolerance of aluminum and chromium is another approach to decrease HLW glass volume. It is likely that an optimum condition can be found by both performing leaching and improving

  9. Mercuric ion reduction and resistance in transgenic Arabidopsis thaliana plants expressing a modified bacterial merA gene.

    PubMed Central

    Rugh, C L; Wilde, H D; Stack, N M; Thompson, D M; Summers, A O; Meagher, R B

    1996-01-01

    With global heavy metal contamination increasing, plants that can process heavy metals might provide efficient and ecologically sound approaches to sequestration and removal. Mercuric ion reductase, MerA, converts toxic Hg2+ to the less toxic, relatively inert metallic mercury (Hg0) The bacterial merA sequence is rich in CpG dinucleotides and has a highly skewed codon usage, both of which are particularly unfavorable to efficient expression in plants. We constructed a mutagenized merA sequence, merApe9, modifying the flanking region and 9% of the coding region and placing this sequence under control of plant regulatory elements. Transgenic Arabidopsis thaliana seeds expressing merApe9 germinated, and these seedlings grew, flowered, and set seed on medium containing HgCl2 concentrations of 25-100 microM (5-20 ppm), levels toxic to several controls. Transgenic merApe9 seedlings evolved considerable amounts of Hg0 relative to control plants. The rate of mercury evolution and the level of resistance were proportional to the steady-state mRNA level, confirming that resistance was due to expression of the MerApe9 enzyme. Plants and bacteria expressing merApe9 were also resistant to toxic levels of Au3+. These and other data suggest that there are potentially viable molecular genetic approaches to the phytoremediation of metal ion pollution. Images Fig. 2 Fig. 3 Fig. 4 PMID:8622910

  10. Electrically conductive anodized aluminum coatings

    NASA Technical Reports Server (NTRS)

    Alwitt, Robert S. (Inventor); Liu, Yanming (Inventor)

    2001-01-01

    A process for producing anodized aluminum with enhanced electrical conductivity, comprising anodic oxidation of aluminum alloy substrate, electrolytic deposition of a small amount of metal into the pores of the anodized aluminum, and electrolytic anodic deposition of an electrically conductive oxide, including manganese dioxide, into the pores containing the metal deposit; and the product produced by the process.

  11. Aluminum Sulfate 18 Hydrate

    ERIC Educational Resources Information Center

    Young, Jay A.

    2004-01-01

    A chemical laboratory information profile (CLIP) of the chemical, aluminum sulfate 18 hydrate, is presented. The profile lists physical and harmful properties, exposure limits, reactivity risks, and symptoms of major exposure for the benefit of teachers and students using the chemical in the laboratory.

  12. Markets for recovered aluminum

    SciTech Connect

    Not Available

    1993-04-01

    The study describes the operation of the markets for scrap aluminum as an example of how recycling markets are structured, what factors influence the supply of and demand for materials, what projections can be made about recycling markets, and how government policies to increase recycling may affect these markets.

  13. Fluxless aluminum brazing

    DOEpatents

    Werner, W.J.

    1974-01-01

    This invention relates to a fluxless brazing alloy for use in forming brazed composites made from members of aluminum and its alloys. The brazing alloy consists of 35-55% Al, 10--20% Si, 25-60% Ge; 65-88% Al, 2-20% Si, 2--18% In; 65--80% Al, 15-- 25% Si, 5- 15% Y. (0fficial Gazette)

  14. Aluminum battery alloys

    DOEpatents

    Thompson, D.S.; Scott, D.H.

    1984-09-28

    Aluminum alloys suitable for use as anode structures in electrochemical cells are disclosed. These alloys include iron levels higher than previously felt possible, due to the presence of controlled amounts of manganese, with possible additions of magnesium and controlled amounts of gallium.

  15. Aluminum battery alloys

    DOEpatents

    Thompson, David S.; Scott, Darwin H.

    1985-01-01

    Aluminum alloys suitable for use as anode structures in electrochemical cs are disclosed. These alloys include iron levels higher than previously felt possible, due to the presence of controlled amounts of manganese, with possible additions of magnesium and controlled amounts of gallium.

  16. Aluminum Sulfate 18 Hydrate

    ERIC Educational Resources Information Center

    Young, Jay A.

    2004-01-01

    A chemical laboratory information profile (CLIP) of the chemical, aluminum sulfate 18 hydrate, is presented. The profile lists physical and harmful properties, exposure limits, reactivity risks, and symptoms of major exposure for the benefit of teachers and students using the chemical in the laboratory.

  17. REMOVAL OF ALUMINUM COATINGS

    DOEpatents

    Peterson, J.H.

    1959-08-25

    A process is presented for dissolving aluminum jackets from uranium fuel elements without attack of the uranium in a boiling nitric acid-mercuric nitrate solution containing up to 50% by weight of nitrtc acid and mercuric nitrate in a concentration of between 0.05 and 1% by weight.

  18. Bonding aluminum beam leads

    NASA Technical Reports Server (NTRS)

    Burkett, F. S.

    1978-01-01

    Report makes it relatively easy for hybrid-circuit manufacturers to convert integrated circuit chips with aluminum bead leads. Report covers: techniques for handling tiny chips; proper geometries for ultrasonic bonding tips; best combinations of pressure, pulse time, and ultrasonic energy for bonding; and best thickness for metal films to which beam leads are bonded.

  19. The expression of cell proliferation-related genes in early developing flowers is affected by a fruit load reduction in tomato plants.

    PubMed

    Baldet, Pierre; Hernould, Michel; Laporte, Frédéric; Mounet, Fabien; Just, Daniel; Mouras, Armand; Chevalier, Christian; Rothan, Christophe

    2006-01-01

    Changes in photoassimilate partitioning between source and sink organs significantly affect fruit development and size. In this study, a comparison was made of tomato plants (Solanum lycopersicum L.) grown under a low fruit load (one fruit per truss, L1 plants) and under a standard fruit load (five fruits per truss, L5 plants), at morphological, biochemical, and molecular levels. Fruit load reduction resulted in increased photoassimilate availability in the plant and in increased growth rates in all plant organs analysed (root, stem, leaf, flower, and fruit). Larger flower and fruit size in L1 plants were correlated with higher cell number in the pre-anthesis ovary. This was probably due to the acceleration of the flower growth rate since other flower developmental parameters (schedule and time-course) remained otherwise unaffected. Using RT-PCR, it was shown that the transcript levels of CYCB2;1 (cyclin) and CDKB2;1 (cyclin-dependent kinase), two mitosis-specific genes, strongly increased early in developing flower buds. Remarkably, the transcript abundance of CYCD3;1, a D-type cyclin potentially involved in cell cycle regulation in response to mitogenic signals, also increased by more than 5-fold at very early stages of L1 flower development. By contrast, transcripts from fw2.2, a putative negative regulator of cell division in tomato fruit, strongly decreased in developing flower bud, as confirmed by in situ hybridization studies. Taken together, these results suggest that changes in carbohydrate partitioning could control fruit size through the regulation of cell proliferation-related genes at very early stages of flower development.

  20. Root-shoot interactions explain the reduction of leaf mineral content in Arabidopsis plants grown under elevated [CO2 ] conditions.

    PubMed

    Jauregui, Ivan; Aparicio-Tejo, Pedro M; Avila, Concepción; Cañas, Rafael; Sakalauskiene, Sandra; Aranjuelo, Iker

    2016-09-01

    Although shoot N depletion in plants exposed to elevated [CO2 ] has already been reported on several occasions, some uncertainty remains about the mechanisms involved. This study illustrates (1) the importance of characterizing root-shoot interactions and (2) the physiological, biochemical and gene expression mechanisms adopted by nitrate-fed Arabidopsis thaliana plants grown under elevated [CO2 ]. Elevated [CO2 ] increases biomass and photosynthetic rates; nevertheless, the decline in total soluble protein, Rubisco and leaf N concentrations revealed a general decrease in leaf N availability. A transcriptomic approach (conducted at the root and shoot level) revealed that exposure to 800 ppm [CO2 ] induced the expression of genes involved in the transport of nitrate and mineral elements. Leaf N and mineral status revealed that N assimilation into proteins was constrained under elevated [CO2 ]. Moreover, this study also highlights how elevated [CO2 ] induced the reorganization of nitrate assimilation between tissues; root nitrogen assimilation was favored over leaf assimilation to offset the decline in nitrogen metabolism in the leaves of plants exposed to elevated [CO2 ]. © 2016 Scandinavian Plant Physiology Society.

  1. Astaxanthin ameliorates aluminum chloride-induced spatial memory impairment and neuronal oxidative stress in mice.

    PubMed

    Al-Amin, Md Mamun; Reza, Hasan Mahmud; Saadi, Hasan Mahmud; Mahmud, Waich; Ibrahim, Abdirahman Adam; Alam, Musrura Mefta; Kabir, Nadia; Saifullah, A R M; Tropa, Sarjana Tarannum; Quddus, A H M Ruhul

    2016-04-15

    Aluminum chloride induces neurodegenerative disease in animal model. Evidence suggests that aluminum intake results in the activation of glial cells and generation of reactive oxygen species. By contrast, astaxanthin is an antioxidant having potential neuroprotective activity. In this study, we investigate the effect of astaxanthin on aluminum chloride-exposed behavioral brain function and neuronal oxidative stress (OS). Male Swiss albino mice (4 months old) were divided into 4 groups: (i) control (distilled water), (ii) aluminum chloride, (iii) astaxanthin+aluminum chloride, and (iv) astaxanthin. Two behavioral tests; radial arm maze and open field test were conducted, and OS markers were assayed from the brain and liver tissues following 42 days of treatment. Aluminum exposed group showed a significant reduction in spatial memory performance and anxiety-like behavior. Moreover, aluminum group exhibited a marked deterioration of oxidative markers; lipid peroxidation (MDA), nitric oxide (NO), glutathione (GSH) and advanced oxidation of protein products (AOPP) in the brain. To the contrary, co-administration of astaxanthin and aluminum has shown improved spatial memory, locomotor activity, and OS. These results indicate that astaxanthin improves aluminum-induced impaired memory performances presumably by the reduction of OS in the distinct brain regions. We suggest a future study to determine the underlying mechanism of astaxanthin in improving aluminum-exposed behavioral deficits. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Reducing Strength Prevailing at Root Surface of Plants Promotes Reduction of Ag+ and Generation of Ag0/Ag2O Nanoparticles Exogenously in Aqueous Phase

    PubMed Central

    Pardha-Saradhi, Peddisetty; Yamal, Gupta; Peddisetty, Tanuj; Sharmila, Peddisetty; Nagar, Shilpi; Singh, Jyoti; Nagarajan, Rajamani; Rao, Kottapalli S.

    2014-01-01

    Potential of root system of plants from wide range of families to effectively reduce membrane impermeable ferricyanide to ferrocyanide and blue coloured 2,6-dichlorophenol indophenol (DCPIP) to colourless DCPIPH2 both under non-sterile and sterile conditions, revealed prevalence of immense reducing strength at root surface. As generation of silver nanoparticles (NPs) from Ag+ involves reduction, present investigations were carried to evaluate if reducing strength prevailing at surface of root system can be exploited for reduction of Ag+ and exogenous generation of silver-NPs. Root system of intact plants of 16 species from 11 diverse families of angiosperms turned clear colorless AgNO3 solutions, turbid brown. Absorption spectra of these turbid brown solutions showed silver-NPs specific surface plasmon resonance peak. Transmission electron microscope coupled with energy dispersive X-ray confirmed the presence of distinct NPs in the range of 5–50 nm containing Ag. Selected area electron diffraction and powder X-ray diffraction patterns of the silver NPs showed Bragg reflections, characteristic of crystalline face-centered cubic structure of Ag0 and cubic structure of Ag2O. Root system of intact plants raised under sterile conditions also generated Ag0/Ag2O-NPs under strict sterile conditions in a manner similar to that recorded under non-sterile conditions. This revealed the inbuilt potential of root system to generate Ag0/Ag2O-NPs independent of any microorganism. Roots of intact plants reduced triphenyltetrazolium to triphenylformazon and impermeable ferricyanide to ferrocyanide, suggesting involvement of plasma membrane bound dehydrogenases in reduction of Ag+ and formation of Ag0/Ag2O-NPs. Root enzyme extract reduced triphenyltetrazolium to triphenylformazon and Ag+ to Ag0 in presence of NADH, clearly establishing potential of dehydrogenases to reduce Ag+ to Ag0, which generate Ag0/Ag2O-NPs. Findings presented in this manuscript put forth a novel, simple

  3. SOLDERING OF ALUMINUM BASE METALS

    DOEpatents

    Erickson, G.F.

    1958-02-25

    This patent deals with the soldering of aluminum to metals of different types, such as copper, brass, and iron. This is accomplished by heating the aluminum metal to be soldered to slightly above 30 deg C, rubbing a small amount of metallic gallium into the part of the surface to be soldered, whereby an aluminum--gallium alloy forms on the surface, and then heating the aluminum piece to the melting point of lead--tin soft solder, applying lead--tin soft solder to this alloyed surface, and combining the aluminum with the other metal to which it is to be soldered.

  4. Rapid manufacturing of aluminum components.

    PubMed

    Sercombe, T B; Schaffer, G B

    2003-08-29

    A manufacturing technique for the production of aluminum components is described. A resin-bonded part is formed by a rapid prototyping technique and then debound and infiltrated by a second aluminum alloy under a nitrogen atmosphere. During thermal processing, the aluminum reacts with the nitrogen and is partially transformed into a rigid aluminum nitride skeleton, which provides the structural rigidity during infiltration. The simplicity and rapidity of this process in comparison to conventional production routes, combined with the ability to fabricate complicated parts of almost any geometry and with high dimensional precision, provide an additional means to manufacture aluminum components.

  5. Oxide-assisted laser surfacing of aluminum

    NASA Astrophysics Data System (ADS)

    Hoepp, E. E.; Kerr, Hugh W.

    1996-04-01

    CO2 laser processing has been carried out on pure aluminum substrates for travel speeds from 0.3 to 6.1 mm/s, using laser powers of about 100 W or 300 W, with various preplaced single or mixed powders including CoO, NiO, SiO2, Fe2O3 or TiO2 usually combined with enough aluminum powder to permit complete reduction of the oxides. The 100 W laser experiments included low, normal and high gravity experiments. The resulting tracks were tested qualitatively for scratch resistance, and examined metallographically. Two types of surfacing were observed; continuous oxide layers produced by melting and an oxidation- reduction reaction of the original oxides with aluminum, and alloying of the substrate by elements reduced by the reaction. Low gravity experiments produced more uniform thicknesses and generally less cracking in the continuous oxides than normal or high gravity experiments. Alloying of the substrate ranged from almost 100% intermetallic layers at low laser powers and low travel speeds to complex mixtures and bands of different phases, depending on the temporal stability of the process, the powder composition and thickness, the laser power and travel speed. Optimization of the process could provide useful wear resistant coatings in a space environment.

  6. Nanoparticles of wurtzite aluminum nitride from the nut shells

    NASA Astrophysics Data System (ADS)

    Qadri, S. B.; Gorzkowski, E. P.; Rath, B. B.; Feng, C. R.; Amarasinghe, R.

    2016-11-01

    Nanoparticles of aluminum nitride were produced from a thermal treatment of a mixture of aluminum oxide (Al2O3) and shells of almond, cashew, coconuts, pistachio, and walnuts in a nitrogen atmosphere at temperatures in excess of 1450 °C. By selecting the appropriate ratios of each nut powder to Al2O3, it is shown that stoichiometric aluminum nitride can be produced by carbo-thermal reduction in nitrogen atmosphere. Using x-ray diffraction analysis, Raman scattering and Fourier Transform Infrared spectroscopy, it is demonstrated that aluminum nitride consists of pure wurtzite phase. Transmission electron microscopy showed the formation of nanoparticles and in some cases nanotubes of AlN.

  7. Hydrogen effects on the age hardening behavior of 2024 aluminum

    NASA Technical Reports Server (NTRS)

    Wagner, J. A.; Louthan, M. R., Jr.; Sisson, R. D., Jr.

    1986-01-01

    It has been found that the fatigue crack growth rate in aluminum alloys increases significantly in the presence of moisture. This phenomenon along with a moisture effect observed in another context has been attributed to 'embrittlement' of the aluminum by absorbed hydrogen generated by the reaction of moisture with freshly exposed aluminum. A description is given of a number of age hardening experiments involving 2024 aluminum. These experiments show that a mechanism related to the segregation of absorbed hydrogen to the coherent theta-double-prime interfaces may account for the observed reduction in fatigue life. It is pointed out that this segregation promotes a loss of coherency in the hydrogen rich region at a fatigue crack tip. Subsequently, the loss of coherency causes local softening and reduces fatigue life.

  8. Effects of aluminum and zirconia contents on the reaction bonded aluminum oxide process

    NASA Astrophysics Data System (ADS)

    Sheedy, Paul Martin

    The effects of aluminum and ZrO2 contents on the reaction and sintering of reaction bonded aluminum oxide (RBAO) were investigated. It was apparent that ZrO2-containing RBAO powders with higher initial aluminum contents (>45 vol%) were increasingly more difficult to react and sinter. During oxidation in air, samples often underwent a self-propagating high-temperature synthesis (SHS) reaction which led to catastrophic failure. This reaction and cracking behavior was more pronounced with increasing aluminum and ZrO2 contents of the powders. Subsequently, it was shown that the SHS reaction was actually two combustion phenomena: a thermal explosion reaction on the surface of the sample between aluminum and oxygen, which (in ZrO2-containing samples) triggered a self propagating aluminothermic reduction of ZrO2, forming Al2O3 and Al 3Zr. Therefore, methods for controlling the rate of the initial oxidation reaction were effective since both SHS reactions were prevented. Despite the use of controlled firing, initial samples with increasing aluminum contents proved difficult to densify. It was found that in all RBAO samples (regardless of ZrO2 content), the reactively formed Al 2O3 underwent the gamma to alpha-Al2O 3 transformation, which resulted in the development of a vermicular microstructure. In ZrO2-containing RBAO samples, this transformation was inhibited and occurred concurrently with the start of densification. In addition, the start of bulk shrinkage in these samples was delayed and the densification rates were decreased in comparison to samples without ZrO 2. This ultimately resulted in a decrease in the limiting density to which ZrO2-containing RBAO samples could be sintered. Surprisingly, in samples without ZrO2, increasing the aluminum content did not appear to have any effects upon the densification behavior of RBAO. In examining RBAO samples with similar aluminum contents but increasing ZrO2 contents, it became apparent that the grain growth inhibiting

  9. Pre-fire fuel reduction treatments influence plant communities and exotic species 9 years after a large wildfire

    Treesearch

    Kristen L. Shive; Amanda M. Kuenzi; Carolyn H. Sieg; Peter Z. Fule

    2013-01-01

    We used a multi-year data set from the 2002 Rodeo-Chediski Fire to detect post-fire trends in plant community response in burned ponderosa pine forests. Within the burn perimeter, we examined the effects of pre-fire fuels treatments on post-fire vegetation by comparing paired treated and untreated sites on the Apache-Sitgreaves National Forest.We sampled these paired...

  10. Reduction of the Cytosolic Phosphoglucomutase in Arabidopsis Reveals Impact on Plant Growth, Seed and Root Development, and Carbohydrate Partitioning

    PubMed Central

    Malinova, Irina; Kunz, Hans-Henning; Alseekh, Saleh; Herbst, Karoline; Fernie, Alisdair R.; Gierth, Markus; Fettke, Joerg

    2014-01-01

    Phosphoglucomutase (PGM) catalyses the interconversion of glucose 1-phosphate (G1P) and glucose 6-phosphate (G6P) and exists as plastidial (pPGM) and cytosolic (cPGM) isoforms. The plastidial isoform is essential for transitory starch synthesis in chloroplasts of leaves, whereas the cytosolic counterpart is essential for glucose phosphate partitioning and, therefore, for syntheses of sucrose and cell wall components. In Arabidopsis two cytosolic isoforms (PGM2 and PGM3) exist. Both PGM2 and PGM3 are redundant in function as single mutants reveal only small or no alterations compared to wild type with respect to plant primary metabolism. So far, there are no reports of Arabidopsis plants lacking the entire cPGM or total PGM activity, respectively. Therefore, amiRNA transgenic plants were generated and used for analyses of various parameters such as growth, development, and starch metabolism. The lack of the entire cPGM activity resulted in a strongly reduced growth revealed by decreased rosette fresh weight, shorter roots, and reduced seed production compared to wild type. By contrast content of starch, sucrose, maltose and cell wall components were significantly increased. The lack of both cPGM and pPGM activities in Arabidopsis resulted in dwarf growth, prematurely die off, and inability to develop a functional inflorescence. The combined results are discussed in comparison to potato, the only described mutant with lack of total PGM activity. PMID:25401493

  11. Recovery and distribution of incinerated aluminum packaging waste.

    PubMed

    Hu, Y; Bakker, M C M; de Heij, P G

    2011-12-01

    A study was performed into relations between physical properties of aluminum packaging waste and the corresponding aluminum scraps in bottom ash from three typical incineration processes. First, Dutch municipal solid waste incineration (MSWI) bottom ash was analyzed for the identifiable beverage can alloy scraps in the +2mm size ranges using chemical detection and X-ray fluorescence. Second, laboratory-scale pot furnace tests were conducted to investigate the relations between aluminum packaging in base household waste and the corresponding metal recovery rates. The representative packaging wastes include beverage cans, foil containers and thin foils. Third, small samples of aluminum packaging waste were incinerated in a high-temperature oven to determine leading factors influencing metal recovery rates. Packaging properties, combustion conditions, presence of magnesium and some specific contaminants commonly found in household waste were investigated independently in the high-temperature oven. In 2007, the bottom ash (+2mm fraction) from the AEB MSWI plant was estimated to be enriched by 0.1 wt.% of aluminum beverage cans scrap. Extrapolating from this number, the recovery potential of all eleven MSWI plants in the Netherlands is estimated at 720 ton of aluminum cans scrap. More than 85 wt.% of this estimate would end up in +6mm size fractions and were amenable for efficient recycling. The pot furnace tests showed that the average recovery rate of metallic aluminum typically decreases from beverage cans (93 wt.%) to foil containers (85 wt.%) to thin foils (77 wt.%). The oven tests showed that in order of decreasing impact the main factors promoting metallic aluminum losses are the packaging type, combustion temperature, residence time and salt contamination. To a lesser degree magnesium as alloying element, smaller packaging size and basic contaminations may also promote losses.

  12. Influence of aluminum on growth, mineral nutrition and organic acid exudation of rambutan (Nephelium lappaceum)

    USDA-ARS?s Scientific Manuscript database

    A randomized complete block design experiment with six aluminum (Al) concentrations was carried out to evaluate the effect of aluminum on nutrient content, plant growth, dry matter production and Al-induced organic acid exudation in rambutan (Nephelium lappaceum). One rambutan cultivar was grown in...

  13. Reduction in NO{sub x} emissions from an industrial sewage sludge incineration plant by employing primary measures in a fluidized bed furnace

    SciTech Connect

    Ludwig, P.; Stamer, F.

    1999-07-01

    The results of an inquiry in 1997 show that the percentage of sewage sludge disposed of by incineration in Germany is 19%. Legal developments in Germany clearly show that this percentage amount is expected to increase in the next few years. According to legislation, the treatment of the sewage sludge will have to achieve a result of {le}5% combustible (according to TA-Siedlungsabfall, i.e., Technical guideline for handling and disposal of urban waste). Sewage sludge incineration will therefore become a preferred treatment process. Fluidized bed combustion is especially suitable in relation to the burn-up results. Around 19 sewage sludge incineration plants are operating in Germany, 17 of which have stationary fluidized bed furnaces, the others are multiple hearth roasters. The German statutory law affecting emissions from sewage sludge incineration plants is 17.BlmSchV (i.e., Paragraph 17 of the Federal Emissions Control Regulations). These regulations stipulate mandatory compliance with limit values as a daily average value figured in standard conditions. The intention is to build up an overview of the various possibilities to reduce the NO{sub x} emissions from one problematic industrial sludge by using primary measures, and if possible, to avoid expensive secondary measures, like the SNCR (selective non catalytic reduction) or SCR (selective catalytic reduction) processes.

  14. Aluminum toxicity and albumin.

    PubMed

    Kelly, A T; Short, B L; Rains, T C; May, J C; Progar, J J

    1989-01-01

    During a study of priming solutions for extracorporeal membrane oxygenation (ECMO) in the intensive care nursery, it was discovered that those solutions using certain brands of 25% albumin contained aluminum levels within the toxic range. When the brand was changed to a brand known to have a lower aluminum (Al) content, a marked drop in priming solution Al levels was measured. The heat exchanger was examined as a possible source of soluble Al. No evidence of elevated Al levels was found in fluids perfusing this heat exchanger when compared with a stainless steel heat exchanger. The Al content of various blood products was evaluated along with various brands of 5% albumin and 25% albumin.

  15. Significant reduction in energy for plant-growth lighting in space using targeted LED lighting and spectral manipulation

    NASA Astrophysics Data System (ADS)

    Poulet, L.; Massa, G. D.; Morrow, R. C.; Bourget, C. M.; Wheeler, R. M.; Mitchell, C. A.

    2014-07-01

    Bioregenerative life-support systems involving photoautotrophic organisms will be necessary to sustain long-duration crewed missions at distant space destinations. Since sufficient sunlight will not always be available for plant growth at many space destinations, efficient electric-lighting solutions are greatly needed. The present study demonstrated that targeted plant lighting with light-emitting diodes (LEDs) and optimizing spectral parameters for close-canopy overhead LED lighting allowed the model crop leaf lettuce (Lactuca sativa L. cv. 'Waldmann's Green') to be grown using significantly less electrical energy than using traditional electric-lighting sources. Lettuce stands were grown hydroponically in a growth chamber controlling temperature, relative humidity, and CO2 level. Several red:blue ratios were tested for growth rate during the lag phase of lettuce growth. In addition, start of the exponential growth phase was evaluated. Following establishment of a 95% red + 5% blue spectral balance giving the best growth response, the energy efficiency of a targeted lighting system was compared with that of two total coverage (untargeted) LED lighting systems throughout a crop-production cycle, one using the same proportion of red and blue LEDs and the other using white LEDs. At the end of each cropping cycle, whole-plant fresh and dry mass and leaf area were measured and correlated with the amount of electrical energy (kWh) consumed for crop lighting. Lettuce crops grown with targeted red + blue LED lighting used 50% less energy per unit dry biomass accumulated, and the total coverage white LEDs used 32% less energy per unit dry biomass accumulated than did the total coverage red + blue LEDs. An energy-conversion efficiency of less than 1 kWh/g dry biomass is possible using targeted close-canopy LED lighting with spectral optimization. This project was supported by NASA grant NNX09AL99G.

  16. Co-conditioning of the anaerobic digested sludge of a municipal wastewater treatment plant with alum sludge: benefit of phosphorus reduction in reject water.

    PubMed

    Yang, Y; Zhao, Y Q; Babatunde, A O; Kearney, P

    2007-12-01

    In this study, alum sludge was introduced to co-conditioning and dewatering with an anaerobic digested sludge from a municipal wastewater treatment plant, to examine the role of the alum sludge in improving the dewaterbility of the mixed sludge and also in immobilizing phosphorus in the reject water. Experiments have demonstrated that the optimal mix ratio for the two sludges is 2:1 (anaerobic digested sludge:alum sludge: volume basis), and this can bring approximately 99% phosphorus reduction in the reject water through the adsorption of phosphorus by alum in the sludge. The phosphorus loading in wastewater treatment plants is itself derived from the recycling of reject water during the wastewater treatment process. Consequently, this co-conditioning and dewatering strategy can achieve a significant reduction in phosphorus loading in wastewater treatment plants. In addition, the use of the alum sludge has been shown to beneficially enhance the dewaterability of the resultant mixed sludge, by decreasing both the specific resistance to filtration and the capillary suction time. This is attributed to the alum sludge acting in charge neutralization and/or as adsorbent for phosphate in the aqueous phase of the sludge. Experiments have also demonstrated that the optimal polymer (Superfloc C2260, Cytec, Botlek, Netherlands) dose for the anaerobic digested sludge was 120 mg/L, while the optimal dose for the mixed sludge (mix ratio 2:1) was 15 mg/L, highlighting a huge savings in polymer addition. Therefore, from the technical perspective, the co-conditioning and dewatering strategy can be viewed as a "win-win" situation. However, for its full-scale application, integrated cost-effective analysis of process capabilities, sludge transport, increased cake disposal, additional administration, polymer saving, and so on, should be factored in.

  17. Aluminum Alloy 7050 Extrusions.

    DTIC Science & Technology

    1977-03-01

    Artificial Aging Conditions 250 A-l Fatigue Crack Growth Data for C5A Extruded Panel, 7050-T7351X, L-T Orientation, R=0.1 254 A-2 Fatigue...cooldd aluminum and steel bottom blocks (Figure 2) were fabricated for use with this tooling. Metal was melted in a 10,000-lb capacity open- hearth ...time factor, effects of heating through this temperature range to the maximum artificial agirg temperature are additive. The solution of the

  18. A simplified approach to analyze the effectiveness of NO2 and SO2 emission reduction of coal-fired power plant from OMI retrievals

    NASA Astrophysics Data System (ADS)

    Bai, Yang; Wu, Lixin; Zhou, Yuan; Li, Ding

    2017-04-01

    Nitrogen oxides (NOX) and sulfur dioxide (SO2) emissions from coal combustion, which is oxidized quickly in the atmosphere resulting in secondary aerosol formation and acid deposition, are the main resource causing China's regional fog-haze pollution. Extensive literature has estimated quantitatively the lifetimes and emissions of NO2 and SO2 for large point sources such as coal-fired power plants and cities using satellite measurements. However, rare of these methods is suitable for sources located in a heterogeneously polluted background. In this work, we present a simplified emission effective radius extraction model for point source to study the NO2 and SO2 reduction trend in China with complex polluted sources. First, to find out the time range during which actual emissions could be derived from satellite observations, the spatial distribution characteristics of mean daily, monthly, seasonal and annual concentration of OMI NO2 and SO2 around a single power plant were analyzed and compared. Then, a 100 km × 100 km geographical grid with a 1 km step was established around the source and the mean concentration of all satellite pixels covered in each grid point is calculated by the area weight pixel-averaging approach. The emission effective radius is defined by the concentration gradient values near the power plant. Finally, the developed model is employed to investigate the characteristic and evolution of NO2 and SO2 emissions and verify the effectiveness of flue gas desulfurization (FGD) and selective catalytic reduction (SCR) devices applied in coal-fired power plants during the period of 10 years from 2006 to 2015. It can be observed that the the spatial distribution pattern of NO2 and SO2 concentration in the vicinity of large coal-burning source was not only affected by the emission of coal-burning itself, but also closely related to the process of pollutant transmission and diffusion caused by meteorological factors in different seasons. Our proposed

  19. A new cadmium reduction device for the microplate determination of nitrate in water, soil, plant tissue, and physiological fluids.

    PubMed

    Crutchfield, James D; Grove, John H

    2011-01-01

    A reusable catalytic reductor consisting of 96 copperized-cadmium pins attached to a microplate lid was developed to simultaneously reduce nitrate (NO3-) to nitrite (NO2-) in all wells of a standard microplate. The resulting NO2- is analyzed colorimetrically by the Griess reaction using a microplate reader. Nitrate data from groundwater samples analyzed using the new device correlated well with data obtained by ion chromatography (r2 = 0.9959). Soil and plant tissue samples previously analyzed for NO3- in an interlaboratory validation study sponsored by the Soil Science Society of America were also analyzed using the new technique. For the soil sample set, the data are shown to correlate well with the other methods used (r2 = 0.9976). Plant data correlated less well, especially for samples containing low concentrations of NO3-. Reasons for these discrepancies are discussed, and new techniques to increase the accuracy of the analysis are explored. In addition, a method is presented for analyzing NO3- in physiological fluids (blood serum and urine) after matrix modification with Somogyi's reagent. A protocol for statistical validation of data when analyzing samples with complex matrixes is also established. The simplicity, adaptability, and low cost of the device indicate its potential for widespread application.

  20. Evaluation of clogging in planted and unplanted horizontal subsurface flow constructed wetlands: solids accumulation and hydraulic conductivity reduction.

    PubMed

    De Paoli, André Cordeiro; von Sperling, Marcos

    2013-01-01

    This study aimed to evaluate the behaviour of two horizontal subsurface flow constructed wetland units regarding solids build up and clogging of the filter medium. In order to analyse the causes of this process, which is considered the major operational problem of constructed wetlands, studies were carried out to characterize accumulated solids and hydraulic conductivity at specific points of the beds of two wetlands (planted with Typha latifolia and unplanted units) receiving effluent from an upflow anaerobic sludge blanket reactor treating sanitary sewage (population equivalent of 50 inhabitants each unit). The experiments were performed after the units were operating for 2 years and 4 months. This study presents comparative results related to the quantification and characterization of accumulated solids and hydraulic conductivity along the length and width of the filter beds. Approximately 80% of the solids found were inorganic (fixed). Near the inlet end, the rate interstitial solids/attached solids was 5.0, while in the outlet end it was reduced to 1.5. Hydraulic conductivity was lower near the inlet of the units (as expected) and, by comparing the planted wetland with the unplanted, the hydraulic conductivity was lower in the former, resulting in larger undesired surface flow.

  1. 21 CFR 73.1645 - Aluminum powder.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Aluminum powder. 73.1645 Section 73.1645 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1645 Aluminum powder. (a) Identity. (1) The color additive aluminum powder shall be composed of finely divided particles of aluminum prepared from virgin aluminum. It...

  2. 21 CFR 73.1645 - Aluminum powder.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Aluminum powder. 73.1645 Section 73.1645 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1645 Aluminum powder. (a) Identity. (1) The color additive aluminum powder shall be composed of finely divided particles of aluminum prepared from virgin aluminum. It...

  3. 21 CFR 73.1645 - Aluminum powder.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Aluminum powder. 73.1645 Section 73.1645 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1645 Aluminum powder. (a) Identity. (1) The color additive aluminum powder shall be composed of finely divided particles of aluminum prepared from virgin aluminum. It...

  4. 21 CFR 73.1645 - Aluminum powder.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Aluminum powder. 73.1645 Section 73.1645 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1645 Aluminum powder. (a) Identity. (1) The color additive aluminum powder shall be composed of finely divided particles of aluminum prepared from virgin aluminum. It...

  5. 21 CFR 73.1645 - Aluminum powder.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Aluminum powder. 73.1645 Section 73.1645 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1645 Aluminum powder. (a) Identity. (1) The color additive aluminum powder shall be composed of finely divided particles of aluminum prepared from virgin aluminum. It...

  6. Extracting aluminum from dross tailings

    NASA Astrophysics Data System (ADS)

    Amer, A. M.

    2002-11-01

    Aluminum dross tailings, an industrial waste, from the Egyptian Aluminium Company (Egyptalum) was used to produce two types of alums: aluminum-sulfate alum [itAl2(SO4)3.12H2O] and ammonium-aluminum alum [ (NH 4)2SO4AL2(SO4)3.24H2O]. This was carried out in two processes. The first process is leaching the impurities using diluted H2SO4 with different solid/liquid ratios at different temperatures to dissolve the impurities present in the starting material in the form of solute sulfates. The second process is the extraction of aluminum (as aluminum sulfate) from the purifi ed aluminum dross tailings thus produced. The effects of temperature, time of reaction, and acid concentration on leaching and extraction processes were studied. The product alums were analyzed using x-ray diffraction and thermal analysis techniques.

  7. Role of three different plants on simultaneous salt and nutrient reduction from saline synthetic wastewater in lab-scale constructed wetlands.

    PubMed

    Jesus, João M; Cassoni, A C; Danko, Anthony S; Fiúza, António; Borges, Maria-Teresa

    2017-02-01

    Constructed Wetlands (CWs) can be a valuable technology to treat high salinity wastewaters but it is not known their potential for removal of both nutrients and salt, and the type of plants to use. This study evaluated the effect of three plants on salt reduction and simultaneous nutrient removal in CWs microcosms with expanded clay and in hydroponic conditions. Initial values of the synthetic wastewater tested were EC=15dSm(-1), SAR=151; NH4(+)-N=24mgL(-1); PO4(3-)-P=30mgL(-1) and NO3(-)-N=34mgL(-1). With expanded clay CW removal efficiency for NH4(+)-N was 21, 88 and 85%, while for NO3(-)-N, it was 4, 56 and 68% for Spartina maritima, Juncus maritimus and Arundo donax, respectively. PO4(3-)-P was adsorbed completely in the expanded clay. However, in hydroponic system, removal efficiencies for NH4(+)-N were 53 and 50%, while PO4(3-)-P removal was 89 and -14% for Spartina maritima and Juncus maritimus, respectively. Nutrient removal in planted microcosms was statistically higher than unplanted controls for NH4(+)-N and PO4(3-)-P. However, salt removal was apparent in the hydroponic system only after 23days of HRT, despite clear salt excretion visible in both Spartina maritima and Juncus maritimus. This study demonstrates the potential of two halophytic plants for saline wastewater treatment. However, salt removal in such a scenario could not be well documented and might prove to be impractical in future work.

  8. Carbon Nanotube Aluminum Matrix Composites

    DTIC Science & Technology

    2010-08-01

    replacement of air space with the polymer matrix. A similar affinity is not known to exist between CNTs and aluminum , where the wetting angle between...Carbon Nanotube Aluminum Matrix Composites by Brent J. Carey, Jerome T. Tzeng, and Shashi Karna ARL-TR-5252 August 2010...Nanotube Aluminum Matrix Composites Brent J. Carey, Jerome T. Tzeng, and Shashi Karna Weapons and Materials Research Directorate, ARL

  9. Possible greenhouse effects of tetrafluoromethane and carbon dioxide emitted from aluminum production

    NASA Astrophysics Data System (ADS)

    Weston, Ralph E.

    Tetrafluoromethane (CF 4) is an extremely stable gas which strongly absorbs infrared radiation at ˜ 8 μm, and therefore is capable of influencing the greenhouse effect. No natural sources have been identified, and the major anthropogenic source appears to be the electrolytic smelting of alumina to produce aluminum. Measurements of CF 4 concentrations in the atmosphere are reviewed, and these are combined with aluminum production rates to provide an estimate of 1.3-3.6 kg of CF 4 emitted per ton of aluminum produced for the period up to ˜ 1985. Aluminum production also requires large amounts of electrical energy, leading to the emission of as much as 22 tons of carbon dioxide per ton of aluminum due to fossil fuel combustion in power plants. The present day contribution of hydroelectric power reduces this figure to about 14 tons of carbon dioxide per ton of aluminum. An estimate of the relative radiative trapping of CF 4 and CO 2 emitted in aluminum production during this same period (1900-1985) indicates that the effect of CF 4 is about one-third that of the CO 2 formed by aluminum production. However, the emission of fluorocarbons from modem aluminum electrolysis cells is much lower than previous estimates indicate, and this factor is considered in estimating potential long-term global warming effects of CF 4 and CO 2 from aluminum production. Possible processes leading to removal of CF 4 from the atmosphere are described.

  10. Laser welding of aluminum alloys

    SciTech Connect

    Leong, K.H.; Sabo, K.R.; Sanders, P.G.; Spawr, W.J.

    1997-03-01

    Recent interest in reducing the weight of automobiles to increase fuel mileage has focused attention on the use of aluminum and associated joining technologies. Laser beam welding is one of the more promising methods for high speed welding of aluminum. Consequently, substantial effort has been expended in attempting to develop a robust laser beam welding process. Early results have not been very consistent in the process requirements but more definitive data has been produced recently. This paper reviews the process parameters needed to obtain consistent laser welds on 5,000 series aluminum alloys and discusses the research necessary to make laser processing of aluminum a reality for automotive applications.

  11. Mineral of the month: aluminum

    USGS Publications Warehouse

    Plunkert, Patricia A.

    2005-01-01

    Aluminum is the second most abundant metallic element in Earth’s crust after silicon. Even so, it is a comparatively new industrial metal that has been produced in commercial quantities for little more than 100 years. Aluminum is lightweight, ductile, malleable and corrosion resistant, and is a good conductor of heat and electricity. Weighing about one-third as much as steel or copper per unit of volume, aluminum is used more than any other metal except iron. Aluminum can be fabricated into desired forms and shapes by every major metalworking technique to add to its versatility.

  12. Modeling to Evaluate Coordination and Flexibility in Aluminum Recycling Operations

    NASA Astrophysics Data System (ADS)

    Brommer, Tracey; Olivetti, Elsa; Fjeldbo, Snorre; Kirchain, Randolph

    Reprocessing of aluminum production byproducts or dross for use in secondary production presents a particular challenge to the aluminum industry. While use of these non-traditional secondary materials is of interest due to their reduced energy and economic burden over virgin counterparts, these materials necessitate the use of particular furnaces, specialized handling and processing conditions. Therefore, to make use of them firms may pursue use of an intermediate recycling facility that can reprocess the secondary materials into a liquid product. After reprocessing downstream aluminum remelters could incorporate the liquid products into their aluminum alloy production schedules. Energy and environmental benefits result from delivering the products as liquid but coordination challenges result because of the energy cost to maintain the liquid. Further coordination challenges result from the need to establish long term recycling production plans in the presence of long term downstream aluminum remelter production uncertainty and inherent variation in the daily order schedule of the downstream aluminum remelters. In this context a fundamental question arises, considering the metallurgical complexities of dross reprocessing, what is the value of operating a coordinated set of by-product reprocessing plants and remelting cast houses?

  13. Environmental dust effects on aluminum surfaces in humid air ambient.

    PubMed

    Yilbas, Bekir Sami; Hassan, Ghassan; Ali, Haider; Al-Aqeeli, Nasser

    2017-04-05

    Environmental dusts settle on surfaces and influence the performance of concentrated solar energy harvesting devices, such as aluminum troughs. The characteristics of environmental dust and the effects of mud formed from the dust particles as a result of water condensing in humid air conditions on an aluminum wafer surface are examined. The dissolution of alkaline and alkaline earth compounds in water condensate form a chemically active mud liquid with pH 8.2. Due to gravity, the mud liquid settles at the interface of the mud and the aluminum surface while forming locally scattered patches of liquid films. Once the mud liquid dries, adhesion work to remove the dry mud increases significantly. The mud liquid gives rise to the formation of pinholes and local pit sites on the aluminum surface. Morphological changes due to pit sites and residues of the dry mud on the aluminum surface lower the surface reflection after the removal of the dry mud from the surface. The characteristics of the aluminum surface can address the dust/mud-related limitations of reflective surfaces and may have implications for the reductions in the efficiencies of solar concentrated power systems.

  14. Environmental dust effects on aluminum surfaces in humid air ambient

    PubMed Central

    Yilbas, Bekir Sami; Hassan, Ghassan; Ali, Haider; Al-Aqeeli, Nasser

    2017-01-01

    Environmental dusts settle on surfaces and influence the performance of concentrated solar energy harvesting devices, such as aluminum troughs. The characteristics of environmental dust and the effects of mud formed from the dust particles as a result of water condensing in humid air conditions on an aluminum wafer surface are examined. The dissolution of alkaline and alkaline earth compounds in water condensate form a chemically active mud liquid with pH 8.2. Due to gravity, the mud liquid settles at the interface of the mud and the aluminum surface while forming locally scattered patches of liquid films. Once the mud liquid dries, adhesion work to remove the dry mud increases significantly. The mud liquid gives rise to the formation of pinholes and local pit sites on the aluminum surface. Morphological changes due to pit sites and residues of the dry mud on the aluminum surface lower the surface reflection after the removal of the dry mud from the surface. The characteristics of the aluminum surface can address the dust/mud-related limitations of reflective surfaces and may have implications for the reductions in the efficiencies of solar concentrated power systems. PMID:28378798

  15. 9. INTERIOR OF LIVING ROOM SHOWING ALUMINUM SLIDING GLASS WINDOW ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. INTERIOR OF LIVING ROOM SHOWING ALUMINUM SLIDING GLASS WINDOW FRONT DOOR, AND ORIGINAL 6-LIGHT OVER 1-LIGHT, DOUBLE-HUNG WINDOWS IN SINGLE AND DOUBLE ARRANGEMENTS. VIEW TO NORTHWEST. - Bishop Creek Hydroelectric System, Plant 4, Worker Cottage, Bishop Creek, Bishop, Inyo County, CA

  16. Responses of Earthworm to Aluminum Toxicity in Latosol

    Treesearch

    Jia-En Zhang; Jiayu Yu; Ying Ouyang; Huaqin. Xu

    2012-01-01

    Excess aluminum (Al) in soils due to acid rain leaching is toxic to water resources and harmful to soil organisms and plants. This study investigated adverse impacts of Al levels upon earthworms (Eisenia fetida) from the latosol (acidic red soil). Laboratory experiments were performed to examine the survival and avoidance of earthworms from high Al...

  17. Secondary Heating Under Quenching Cooling of Aluminum Alloys

    NASA Astrophysics Data System (ADS)

    Tsukrov, S. L.; Ber, L. B.

    2017-07-01

    Variants of secondary heating of aluminum alloys are considered, i.e., under quenching of plates in a water tank or on a horizontal quenching unit with water jet cooling, under continuous quenching of strips, and under quenching of tubes in vertical furnaces. Recommendation are given for removal or substantial reduction of the intensity of secondary heating under industrial conditions.

  18. A stable-isotope dilution GC-MS approach for the analysis of DFRC (derivatization followed by reductive cleavage) monomers from low-lignin plant materials.

    PubMed

    Schäfer, Judith; Urbat, Felix; Rund, Katharina; Bunzel, Mirko

    2015-03-18

    The derivatization followed by reductive cleavage (DFRC) method is a well-established tool to characterize the lignin composition of plant materials. However, the application of the original procedure, especially the chromatographic determination of the DFRC monomers, is problematic for low-lignin foods. To overcome these problems a modified sample cleanup and a stable-isotope dilution approach were developed and validated. To quantitate the diacetylated DFRC monomers, their corresponding hexadeuterated analogs were synthesized and used as internal standards. By using the selected-ion monitoring mode, matrix-associated interferences can be minimized resulting in higher selectivity and sensitivity. The modified method was applied to four low-lignin samples. Lignin from carrot fibers was classified as guaiacyl-rich whereas the lignins from radish, pear, and asparagus fibers where classified as balanced lignins (guaiacyl/syringyl ratio=1-2).

  19. Reduction of starch granule size by expression of an engineered tandem starch-binding domain in potato plants.

    PubMed

    Ji, Qin; Oomen, Ronald J F J; Vincken, Jean-Paul; Bolam, David N; Gilbert, Harry J; Suurs, Luc C J M; Visser, Richard G F

    2004-05-01

    Granule size is an important parameter when using starch in industrial applications. An artificial tandem repeat of a family 20 starch-binding domain (SBD2) was engineered by two copies of the SBD derived from Bacillus circulans cyclodextrin glycosyltransferase via the Pro-Thr-rich linker peptide from Xyn10A from Cellulomonas fimi. SBD2 and a single SBD were introduced into the amylose-free potato mutant, amf, using appropriate signal sequences. The accumulation of SBD2 into transgenic starch granules was much higher than that of SBD. In a number of transformants, particularly amfSS3, the starch granules were much smaller than in control plants. The amfSS3 mean granule size was 7.8 microm, compared with 15.2 microm in the control, whereas other starch properties were unaltered. This new starch combines the advantage of the high purity of potato starch with that of the small granule size of other crop species, such as cassava, taro and wheat. This starch may find application in the manufacture of biodegradable plastic films. Both genes were also expressed in Escherichia coli and the affinity for soluble starch of the purified recombinant proteins was determined. SBD2 had an approximately 10-fold higher affinity for starch than SBD, indicating that the two appended SBDs act in synergy when binding to their target polysaccharide ligand.

  20. Power plant emissions: particulate matter-related health damages and the benefits of alternative emission reduction scenarios

    SciTech Connect

    Schneider, C.

    2004-06-15

    This report estimates the avoidable health effects of each of a series of alternative regulatory scenarios for power plants, focusing on the adverse human health effects due to exposure to fine particulate matter (PM2.5) This report uses the same analytical methods that the U.S. Environmental Protection Agency used in 2003 to prepare an analysis of the potential health effects of the proposed Clear Skies Act (EPA 2003). This report conducts an analysis of the impacts in 2010 and 2020 of three policy alternatives to the proposed Clear Skies Act, The Jeffords/Lieberman/Collins 'The Clean Power Act', S. 366, and the EPA August 2001 Straw Proposal (one of several alternatives EPA analyzed prior to the announcement of the Clear Skies Initiative in 2002). The report also examines the health impacts associated with the total emissions from coal fired electricity generating units in 2010. Chapter 2 describes the emissions inventory estimates, and the changes in the emissions associated with each scenario analyzed. Chapter 3 describes the methods used to estimate changes in particulate matter concentrations. Chapter 4 describes general issues arising in estimating and valuing changes in adverse health effects associated with changes in particulate matter. Chapter 5 describes in some detail the methods used for estimating and valuing adverse health effects, and Chapter 6 presents the results of these analyses. Chapter 7 presents estimates of the impact of these alternative policy options on the PM non-attainment status. 117 refs., 21 figs., 32 tabs., 3 apps.