acid mmaiii leads: Topics by WorldWideScience.org

Sample records for acid mmaiii leads

Monomethylarsonous Acid (MMAIII Has an Adverse Effect on the Innate Immune Response of Human Bronchial Epithelial Cells to Pseudomonas aeruginosa.

Directory of Open Access Journals (Sweden)

Emily G Notch

Full Text Available Arsenic is the number one contaminant of concern with regard to human health according to the World Health Organization. Epidemiological studies on Asian and South American populations have linked arsenic exposure with an increased incidence of lung disease, including pneumonia, and chronic obstructive pulmonary disease, both of which are associated with bacterial infection. However, little is known about the effects of low dose arsenic exposure, or the contributions of organic arsenic to the innate immune response to bacterial infection. This study examined the effects on Pseudomonas aeruginosa (P. aeruginosa induced cytokine secretion by human bronchial epithelial cells (HBEC by inorganic sodium arsenite (iAsIII and two major metabolites, monomethylarsonous acid (MMAIII and dimethylarsenic acid (DMAV, at concentrations relevant to the U.S.Neither iAsIII nor DMAV altered P. aeruginosa induced cytokine secretion. By contrast, MMAIII increased P. aeruginosa induced secretion of IL-8, IL-6 and CXCL2. A combination of iAsIII, MMAIII and DMAV (10 pbb total reduced IL-8 and CXCL1 secretion. These data demonstrate for the first time that exposure to MMAIII alone, and a combination of iAsIII, MMAIII and DMAV at levels relevant to the U.S. may have negative effects on the innate immune response of human bronchial epithelial cells to P. aeruginosa.
Arsenite and monomethylarsonous acid generate oxidative stress response in human bladder cell culture

International Nuclear Information System (INIS)

Eblin, K.E.; Bowen, M.E.; Cromey, D.W.; Bredfeldt, T.G.; Mash, E.A.; Lau, S.S.; Gandolfi, A.J.

2006-01-01

Arsenicals have commonly been seen to induce reactive oxygen species (ROS) which can lead to DNA damage and oxidative stress. At low levels, arsenicals still induce the formation of ROS, leading to DNA damage and protein alterations. UROtsa cells, an immortalized human urothelial cell line, were used to study the effects of arsenicals on the human bladder, a site of arsenical bioconcentration and carcinogenesis. Biotransformation of As(III) by UROtsa cells has been shown to produce methylated species, namely monomethylarsonous acid [MMA(III)], which has been shown to be 20 times more cytotoxic. Confocal fluorescence images of UROtsa cells treated with arsenicals and the ROS sensing probe, DCFDA, showed an increase of intracellular ROS within five min after 1 μM and 10 μM As(III) treatments. In contrast, 50 and 500 nM MMA(III) required pretreatment for 30 min before inducing ROS. The increase in ROS was ameliorated by preincubation with either SOD or catalase. An interesting aspect of these ROS detection studies is the noticeable difference between concentrations of As(III) and MMA(III) used, further supporting the increased cytotoxicity of MMA(III), as well as the increased amount of time required for MMA(III) to cause oxidative stress. These arsenical-induced ROS produced oxidative DNA damage as evidenced by an increase in 8-hydroxyl-2'-deoxyguanosine (8-oxo-dG) with either 50 nM or 5 μM MMA(III) exposure. These findings provide support that MMA(III) cause a genotoxic response upon generation of ROS. Both As(III) and MMA(III) were also able to induce Hsp70 and MT protein levels above control, showing that the cells recognize the ROS and respond. As(III) rapidly induces the formation of ROS, possibly through it oxidation to As(V) and further metabolism to MMA(III)/(V). These studies provide evidence for a different mechanism of MMA(III) toxicity, one that MMA(III) first interacts with cellular components before an ROS response is generated, taking longer to
Monomethylarsonous acid inhibited endogenous cholesterol biosynthesis in human skin fibroblasts

Energy Technology Data Exchange (ETDEWEB)

Guo, Lei [Environmental Toxicology Graduate Program, University of California, Riverside, CA 92521-0403 (United States); Xiao, Yongsheng [Department of Chemistry, University of California, Riverside, CA 92521-0403 (United States); Wang, Yinsheng, E-mail: yinsheng.wang@ucr.edu [Environmental Toxicology Graduate Program, University of California, Riverside, CA 92521-0403 (United States); Department of Chemistry, University of California, Riverside, CA 92521-0403 (United States)

2014-05-15

Human exposure to arsenic in drinking water is a widespread public health concern, and such exposure is known to be associated with many human diseases. The detailed molecular mechanisms about how arsenic species contribute to the adverse human health effects, however, remain incompletely understood. Monomethylarsonous acid [MMA(III)] is a highly toxic and stable metabolite of inorganic arsenic. To exploit the mechanisms through which MMA(III) exerts its cytotoxic effect, we adopted a quantitative proteomic approach, by coupling stable isotope labeling by amino acids in cell culture (SILAC) with LC-MS/MS analysis, to examine the variation in the entire proteome of GM00637 human skin fibroblasts following acute MMA(III) exposure. Among the ∼ 6500 unique proteins quantified, ∼ 300 displayed significant changes in expression after exposure with 2 μM MMA(III) for 24 h. Subsequent analysis revealed the perturbation of de novo cholesterol biosynthesis, selenoprotein synthesis and Nrf2 pathways evoked by MMA(III) exposure. Particularly, MMA(III) treatment resulted in considerable down-regulation of several enzymes involved in cholesterol biosynthesis. In addition, real-time PCR analysis showed reduced mRNA levels of select genes in this pathway. Furthermore, MMA(III) exposure contributed to a distinct decline in cellular cholesterol content and significant growth inhibition of multiple cell lines, both of which could be restored by supplementation of cholesterol to the culture media. Collectively, the present study demonstrated that the cytotoxicity of MMA(III) may arise, at least in part, from the down-regulation of cholesterol biosynthesis enzymes and the resultant decrease of cellular cholesterol content. - Highlights: • MMA(III)-induced perturbation of the entire proteome of GM00637 cells is studied. • Quantitative proteomic approach revealed alterations of multiple cellular pathways. • MMA(III) inhibits de novo cholesterol biosynthesis. • MMA(III
Global gene expression changes in human urothelial cells exposed to low-level monomethylarsonous acid

International Nuclear Information System (INIS)

Medeiros, Matthew; Zheng, Xinghui; Novak, Petr; Wnek, Shawn M.; Chyan, Vivian; Escudero-Lourdes, Claudia; Gandolfi, A. Jay

2012-01-01

Highlights: ► Chronic exposure to 50 nM monomethylarsonous acid in UROtsa was investigated. ► At 3 months of exposure substantial changes were observed in gene expression. ► Notable changes occurred in mitogenic signaling, stress, immune and inflammatory responses. ► Gene expression changes correlate with phenotypic changes from previous studies. -- Abstract: Bladder cancer has been associated with chronic arsenic exposure. Monomethylarsonous acid [MMA(III)] is a metabolite of inorganic arsenic and has been shown to transform an immortalized urothelial cell line (UROtsa) at concentrations 20-fold less than arsenite. MMA(III) was used as a model arsenical to examine the mechanisms of arsenical-induced transformation of urothelium. A microarray analysis was performed to assess the transcriptional changes in UROtsa during the critical window of chronic 50 nM MMA(III) exposure that leads to transformation at 3 months of exposure. The analysis revealed only minor changes in gene expression at 1 and 2 months of exposure, contrasting with substantial changes observed at 3 months of exposure. The gene expression changes at 3 months were analyzed showing distinct alterations in biological processes and pathways such as a response to oxidative stress, enhanced cell proliferation, anti-apoptosis, MAPK signaling, as well as inflammation. Twelve genes selected as markers of these particular biological processes were used to validate the microarray and these genes showed a time-dependent changes at 1 and 2 months of exposure, with the most substantial changes occurring at 3 months of exposure. These results indicate that there is a strong association between the acquired phenotypic changes that occur with chronic MMA(III) exposure and the observed gene expression patterns that are indicative of a malignant transformation. Although the substantial changes that occur at 3 months of exposure may be a consequence of transformation, there are common occurrences of altered
Interleukin-8 (IL-8) over-production and autocrine cell activation are key factors in monomethylarsonous acid [MMA(III)]-induced malignant transformation of urothelial cells

International Nuclear Information System (INIS)

Escudero-Lourdes, C.; Wu, T.; Camarillo, J.M.; Gandolfi, A.J.

2012-01-01

The association between chronic human exposure to arsenicals and bladder cancer development is well recognized; however, the underlying molecular mechanisms have not been fully determined. We propose that inflammatory responses can play a pathogenic role in arsenic-related bladder carcinogenesis. In previous studies, it was demonstrated that chronic exposure to 50 nM monomethylarsenous acid [MMA(III)] leads to malignant transformation of an immortalized model of urothelial cells (UROtsa), with only 3 mo of exposure necessary to trigger the transformation-related changes. In the three-month window of exposure, the cells over-expressed pro-inflammatory cytokines (IL-1β, IL-6 and IL-8), consistent with the sustained activation of NFKβ and AP1/c-jun, ERK2, and STAT3. IL-8 was over-expressed within hours after exposure to MMA(III), and sustained over-expression was observed during chronic exposure. In this study, we profiled IL-8 expression in UROtsa cells exposed to 50 nM MMA(III) for 1 to 5 mo. IL-8 expression was increased mainly in cells after 3 mo MMA(III) exposure, and its production was also found increased in tumors derived from these cells after heterotransplantation in SCID mice. UROtsa cells do express both receptors, CXCR1 and CXCR2, suggesting that autocrine cell activation could be important in cell transformation. Supporting this observation and consistent with IL-8 over-expression, CXCR1 internalization was significantly increased after three months of exposure to MMA(III). The expression of MMP-9, cyclin D1, bcl-2, and VGEF was significantly increased in cells exposed to MMA(III) for 3 mo, but these mitogen-activated kinases were significantly decreased after IL-8 gene silencing, together with a decrease in cell proliferation rate and in anchorage-independent colony formation. These results suggest a relevant role of IL-8 in MMA(III)-induced UROtsa cell transformation. -- Highlights: ► IL-8 is over-expressed in human MMA(III)-exposed urothelial
Expression of selected pathway-marker genes in human urothelial cells exposed chronically to a non-cytotoxic concentration of monomethylarsonous acid

Directory of Open Access Journals (Sweden)

Matthew Medeiros

2014-01-01

Full Text Available Bladder cancer has been associated with chronic arsenic exposure. Monomethylarsonous acid [MMA(III] is a metabolite of inorganic arsenic and has been shown to transform an immortalized urothelial cell line (UROtsa at concentrations 20-fold less than arsenite. MMA(III was used as a model arsenical to examine the mechanisms of arsenical-induced transformation of urothelium. A previous microarray analysis revealed only minor changes in gene expression at 1 and 2 months of chronic exposure to MMA(III, contrasting with substantial changes observed at 3 months of exposure. To address the lack of information between 2 and 3 months of exposure (the critical period of transformation, the expression of select pathway marker genes was measured by PCR array analysis on a weekly basis. Cell proliferation rate, anchorage-independent growth, and tumorigenicity in SCID mice were also assessed to determine the early, persistent phenotypic changes and their association with the changes in expression of these selected marker genes. A very similar pattern of alterations in these genes was observed when compared to the microarray results, and suggested that early perturbations in cell signaling cascades, immunological pathways, cytokine expression, and MAPK pathway are particularly important in driving malignant transformation. These results showed a strong association between the acquired phenotypic changes that occurred as early as 1–2 months of chronic MMA(III exposure, and the observed gene expression pattern that is indicative of the earliest stages in carcinogenesis.
Exposure to monomethylarsonous acid (MMAIII) leads to altered selenoprotein synthesis in a primary human lung cell model

International Nuclear Information System (INIS)

Meno, Sarah R.; Nelson, Rebecca; Hintze, Korry J.; Self, William T.

2009-01-01

Monomethylarsonous acid (MMA III ), a trivalent metabolite of arsenic, is highly cytotoxic and recent cell culture studies suggest that it might act as a carcinogen. The general consensus of studies indicates that the cytotoxicity of MMA III is a result of increased levels of reactive oxygen species (ROS). A longstanding relationship between arsenic and selenium metabolism has led to the use of selenium as a supplement in arsenic exposed populations, however the impact of organic arsenicals (methylated metabolites) on selenium metabolism is still poorly understood. In this study we determined the impact of exposure to MMA III on the regulation of expression of TrxR1 and its activity using a primary lung fibroblast line, WI-38. The promoter region of the gene encoding the selenoprotein thioredoxin reductase 1 (TrxR1) contains an antioxidant responsive element (ARE) that has been shown to be activated in the presence of electrophilic compounds. Results from radiolabeled selenoproteins indicate that exposure to low concentrations of MMA III resulted in increased synthesis of TrxR1 in WI-38 cells, and lower incorporation of selenium into other selenoproteins. MMA III treatment led to increased mRNA encoding TrxR1 in WI-38 cells, while lower levels of mRNA coding for cellular glutathione peroxidase (cGpx) were detected in exposed cells. Luciferase activity of TrxR1 promoter fusions increased with addition of MMA III , as did expression of a rat quinone reductase (QR) promoter fusion construct. However, MMA III induction of the TRX1 promoter fusion was abrogated when the ARE was mutated, suggesting that this regulation is mediated via the ARE. These results indicate that MMA III alters the expression of selenoproteins based on a selective induction of TrxR1, and this response to exposure to organic arsenicals that requires the ARE element.
Serum Neuron-Specific Enolase, Biogenic Amino-Acids and Neurobehavioral Function in Lead-Exposed Workers from Lead-Acid Battery Manufacturing Process

OpenAIRE

K Ravibabu; T Barman; HR Rajmohan

2015-01-01

Background: The interaction between serum neuron-specific enolase (NSE), biogenic amino-acids and neurobehavioral function with blood lead levels in workers exposed to lead form lead-acid battery manufacturing process was not studied. Objective: To evaluate serum NSE and biogenic amino-acids (dopamine and serotonin) levels, and neurobehavioral performance among workers exposed to lead from lead-acid storage battery plant, and its relation with blood lead levels (BLLs). Methods: In a c...
The lead and lead-acid battery industries during 2002 and 2007 in China

Energy Technology Data Exchange (ETDEWEB)

Chen, H.Y.; Li, A.J.; Finlow, D.E. [Key Lab of Electrochemical Technology on Energy Storage and Power Generation in Guangdong Universities, School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China)

2009-06-01

In the past 15 years, the center of the international lead market has shifted to China. China has become the largest producer of raw and refined lead, plus the largest consumer. This paper reviews the status of the lead and lead-acid battery industries in China, including lead mining, lead refining, secondary lead production, the lead-acid battery industry, new opportunities for lead-acid batteries, and the environmental problems associated with lead and lead-acid batteries. The output of raw and refined lead has increased annually in China, and now accounts for more than 30% of the world total. As a result of a change in the Chinese government's policy regarding the export of lead, plus an increase in the price of lead, the profits of Chinese lead manufacturers were significantly reduced, the trade deficit of the Chinese lead industry increased, the operating rates of lead smelter enterprises greatly reduced, and some small enterprises were forced to shut down. At the present time, an increasing number of enterprises have begun to produce secondary lead, and the scale of production has expanded from tens of tons to tens of thousands of tons. In 2006, the output of secondary lead in China reached 700,000 tons, but outdated technology and equipment limited development of the secondary lead industry. Because of serious pollution problems, raw material shortages, and fierce price competition in the battery market, changes in the development of the lead-acid battery industry have been dramatic; approximately one thousand medium-sized and small lead-acid battery producers have been closed in the past 3 years. The output of large lead-acid battery enterprises has not been reduced, however, as a result of their manufacturing technology and equipment being comparable to those in other advanced industrial countries. In China, the flourishing development of electric bicycles, electric tricycles, and photovoltaic energy systems should provide ongoing opportunities for
The lead and lead-acid battery industries during 2002 and 2007 in China

International Nuclear Information System (INIS)

Chen, H.Y.; Li, A.J.; Finlow, D.E.

2009-01-01

In the past 15 years, the center of the international lead market has shifted to China. China has become the largest producer of raw and refined lead, plus the largest consumer. This paper reviews the status of the lead and lead-acid battery industries in China, including lead mining, lead refining, secondary lead production, the lead-acid battery industry, new opportunities for lead-acid batteries, and the environmental problems associated with lead and lead-acid batteries. The output of raw and refined lead has increased annually in China, and now accounts for more than 30% of the world total. As a result of a change in the Chinese government's policy regarding the export of lead, plus an increase in the price of lead, the profits of Chinese lead manufacturers were significantly reduced, the trade deficit of the Chinese lead industry increased, the operating rates of lead smelter enterprises greatly reduced, and some small enterprises were forced to shut down. At the present time, an increasing number of enterprises have begun to produce secondary lead, and the scale of production has expanded from tens of tons to tens of thousands of tons. In 2006, the output of secondary lead in China reached 700,000 tons, but outdated technology and equipment limited development of the secondary lead industry. Because of serious pollution problems, raw material shortages, and fierce price competition in the battery market, changes in the development of the lead-acid battery industry have been dramatic; approximately one thousand medium-sized and small lead-acid battery producers have been closed in the past 3 years. The output of large lead-acid battery enterprises has not been reduced, however, as a result of their manufacturing technology and equipment being comparable to those in other advanced industrial countries. In China, the flourishing development of electric bicycles, electric tricycles, and photovoltaic energy systems should provide ongoing opportunities for the
Sulfation in lead-acid batteries

Science.gov (United States)

Catherino, Henry A.; Feres, Fred F.; Trinidad, Francisco

Virtually, all military land vehicle systems use a lead-acid battery to initiate an engine start. The maintainability of these batteries and as a consequence, system readiness, has suffered from a lack of understanding of the reasons for battery failure. Often, the term most commonly heard for explaining the performance degradation of lead-acid batteries is the word, sulfation. Sulfation is a residual term that came into existence during the early days of lead-acid battery development. The usage is part of the legend that persists as a means for interpreting and justifying the eventual performance deterioration and failure of lead-acid batteries. The usage of this term is confined to the greater user community and, over time, has encouraged a myriad of remedies for solving sulfation problems. One can avoid the connotations associated with the all-inclusive word, sulfation by visualizing the general "sulfation" effect in terms of specific mechanistic models. Also, the mechanistic models are essential for properly understanding the operation and making proper use this battery system. It is evident that the better the model, the better the level of understanding.
The performance of a soluble lead-acid flow battery and its comparison to a static lead-acid battery

International Nuclear Information System (INIS)

Zhang, C.P.; Sharkh, S.M.; Li, X.; Walsh, F.C.; Zhang, C.N.; Jiang, J.C.

2011-01-01

Highlights: → We compared the electrochemical characteristics of two types of the batteries. → SLAFB shows as good performance as SLAB under the same current density. → The cycle life of two batteries is strongly influenced by the depth of discharge. → The cycle life of SLAFB can be extended by treatment with hydrogen peroxide. - Abstract: The electrochemistry of static lead-acid and soluble lead-acid flow batteries is summarised and the differences between the two batteries are highlighted. A general comparison of the performance of an unoptimised soluble lead-acid flow laboratory cell and a commercial lead-acid battery during charge and discharge is reported. The influence of the depth of discharge on cycle life for both batteries is also considered. The flow battery was found to have a better charge efficiency than the static one, but the cells were found to have comparable energy efficiencies. The self-discharge characteristics of the soluble lead-acid battery were also measured and compared to reported values for a commercial static battery. Some self-discharge of the soluble lead-acid flow battery is observed during prolonged periods on open-circuit but the battery could recover its normal performance after a single charge-discharge cycle.
Lead-acid battery technologies fundamentals, materials, and applications

CERN Document Server

Jung, Joey; Zhang, Jiujun

2015-01-01

Lead-Acid Battery Technologies: Fundamentals, Materials, and Applications offers a systematic and state-of-the-art overview of the materials, system design, and related issues for the development of lead-acid rechargeable battery technologies. Featuring contributions from leading scientists and engineers in industry and academia, this book:Describes the underlying science involved in the operation of lead-acid batteriesHighlights advances in materials science and engineering for materials fabricationDelivers a detailed discussion of the mathematical modeling of lead-acid batteriesAnalyzes the
Lightweight, durable lead-acid batteries

Science.gov (United States)

Lara-Curzio, Edgar; An, Ke; Kiggans, Jr., James O; Dudney, Nancy J; Contescu, Cristian I; Baker, Frederick S; Armstrong, Beth L

2013-05-21

A lightweight, durable lead-acid battery is disclosed. Alternative electrode materials and configurations are used to reduce weight, to increase material utilization and to extend service life. The electrode can include a current collector having a buffer layer in contact with the current collector and an electrochemically active material in contact with the buffer layer. In one form, the buffer layer includes a carbide, and the current collector includes carbon fibers having the buffer layer. The buffer layer can include a carbide and/or a noble metal selected from of gold, silver, tantalum, platinum, palladium and rhodium. When the electrode is to be used in a lead-acid battery, the electrochemically active material is selected from metallic lead (for a negative electrode) or lead peroxide (for a positive electrode).
Serum neuron-specific enolase, biogenic amino-acids and neurobehavioral function in lead-exposed workers from lead-acid battery manufacturing process.

Science.gov (United States)

Ravibabu, K; Barman, T; Rajmohan, H R

2015-01-01

The interaction between serum neuron-specific enolase (NSE), biogenic amino-acids and neurobehavioral function with blood lead levels in workers exposed to lead form lead-acid battery manufacturing process was not studied. To evaluate serum NSE and biogenic amino-acids (dopamine and serotonin) levels, and neurobehavioral performance among workers exposed to lead from lead-acid storage battery plant, and its relation with blood lead levels (BLLs). In a cross-sectional study, we performed biochemical and neurobehavioral function tests on 146 workers exposed to lead from lead-acid battery manufacturing process. BLLs were assessed by an atomic absorption spectrophotometer. Serum NSE, dopamine and serotonin were measured by ELISA. Neurobehavioral functions were assessed by CDC-recommended tests---simple reaction time (SRT), symbol digit substitution test (SDST), and serial digit learning test (SDLT). There was a significant correlation (r 0.199, pSDLT and SRT had also a significant positive correlation (r 0.238, p<0.01). NSE had a negative correlation (r -0.194, p<0.05) with serotonin level. Multiple linear regression analysis revealed that both SRT and SDST had positive significant associations with BLL. SRT also had a positive significant association with age. Serum NSE cannot be used as a marker for BLL. The only domain of neurobehavioral function tests that is affected by increased BLL in workers of lead-acid battery manufacturing process is that of the "attention and perception" (SDST).
Serum Neuron-Specific Enolase, Biogenic Amino-Acids and Neurobehavioral Function in Lead-Exposed Workers from Lead-Acid Battery Manufacturing Process

Directory of Open Access Journals (Sweden)

K Ravibabu

2015-01-01

Full Text Available Background: The interaction between serum neuron-specific enolase (NSE, biogenic amino-acids and neurobehavioral function with blood lead levels in workers exposed to lead form lead-acid battery manufacturing process was not studied. Objective: To evaluate serum NSE and biogenic amino-acids (dopamine and serotonin levels, and neurobehavioral performance among workers exposed to lead from lead-acid storage battery plant, and its relation with blood lead levels (BLLs. Methods: In a cross-sectional study, we performed biochemical and neurobehavioral function tests on 146 workers exposed to lead from lead-acid battery manufacturing process. BLLs were assessed by an atomic absorption spectrophotometer. Serum NSE, dopamine and serotonin were measured by ELISA. Neurobehavioral functions were assessed by CDC-recommended tests—simple reaction time (SRT, symbol digit substitution test (SDST, and serial digit learning test (SDLT. Results: There was a significant correlation (r 0.199, p<0.05 between SDST and BLL. SDLT and SRT had also a significant positive correlation (r 0.238, p<0.01. NSE had a negative correlation (r –0.194, p<0.05 with serotonin level. Multiple linear regression analysis revealed that both SRT and SDST had positive significant associations with BLL. SRT also had a positive significant association with age. Conclusion: Serum NSE cannot be used as a marker for BLL. The only domain of neurobehavioral function tests that is affected by increased BLL in workers of lead-acid battery manufacturing process is that of the “attention and perception” (SDST.
Primer on lead-acid storage batteries

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-09-01

This handbook was developed to help DOE facility contractors prevent accidents caused during operation and maintenance of lead-acid storage batteries. Major types of lead-acid storage batteries are discussed as well as their operation, application, selection, maintenance, and disposal (storage, transportation, as well). Safety hazards and precautions are discussed in the section on battery maintenance. References to industry standards are included for selection, maintenance, and disposal.
Technological progress in sealed lead/acid batteries

Science.gov (United States)

Yamashita, J.; Nakashima, H.; Kasai, Y.

A brief review is given of the history of the research and development of sealed lead/acid batteries during the 30 years since, in 1959, the Yuasa Battery Co. introduced a small-sized sealed battery as the power supply for portable television sets. In 1965, Yuasa began the full-scale mass production and sale of a small-sized sealed lead/acid battery under the NOYPER brand. In 1970, the use of a PbCa alloy grid was adopted, and there followed the successful development of a sealed battery with an oxygen-recombination facility. In 1976, Yuasa more or less established the basic technology for the valve-regulated sealed lead/acid battery — the NP battery — which is now the type in general use. Throughout the 1980s, Yuasa, has continued development in order to expand the sphere of application for the production technology of valve-regulated batteries for motorcycles, as well as for stationary duties with large capacities of 100 to 3000 A h. Recently, in order to improve the reliability and boost the output of sealed lead/acid batteries for employment in UPS power sources, Yuasa has been working intently on the design of a valve-regulated lead/acid battery with outstanding characteristics for high-rate discharge and resistance to high temperatures.
The refining of secondary lead for use in advanced lead-acid batteries

International Nuclear Information System (INIS)

Ellis, Timothy W.; Mirza, Abbas H.

2010-01-01

Secondary lead, i.e. material produced by the recycling of lead-acid batteries has become the primary source of lead in much of the world. This has been important to the secondary lead industry as other uses have dwindled, e.g. lead based pigments, chemicals, fuel additives, solders and CRT glasses. Presently, battery manufacturing accounts for greater than 80% of lead consumption while recycled lead accounts for approximately the same market share of lead supply. These two facts strongly demonstrate the battery manufacturing and recycled lead are intimately coupled in everyday life. In this paper we will explore how recycled lead has become the material of choice for battery construction through the development of a recovery and refining process that exceeds the industries requirements. Particular focus will be on addressing the results presented by Prengaman on the effects of contaminant or tramp elements on gassing in lead-acid batteries. (author)
Spent lead-acid battery recycling in China - A review and sustainable analyses on mass flow of lead.

Science.gov (United States)

Sun, Zhi; Cao, Hongbin; Zhang, Xihua; Lin, Xiao; Zheng, Wenwen; Cao, Guoqing; Sun, Yong; Zhang, Yi

2017-06-01

Lead is classified to be one of the top heavy metal pollutants in China. The corresponding environmental issues especially during the management of spent lead-acid battery have already caused significant public awareness and concern. This research gives a brief overview on the recycling situation based on an investigation of the lead industry in China and also the development of technologies for spent lead-acid batteries. The main principles and research focuses of different technologies including pyrometallurgy, hydrometallurgy and greener technologies are summarized and compared. Subsequently, the circulability of lead based on the entire life cycle analyses of lead-acid battery is calculated. By considering different recycling schemes, the recycling situation of spent lead-acid battery in China can be understood semi-quantitatively. According to this research, 30% of the primary lead production can be shut down that the lead production can still ensure consecutive life cycle operation of lead-acid battery, if proper management of the spent lead-acid battery is implemented according to current lead industry situation in China. This research provides a methodology on the view of lead circulability in the whole life cycle of a specific product and is aiming to contribute more quantitative guidelines for efficient organization of lead industry in China. Copyright © 2017 Elsevier Ltd. All rights reserved.

Recycling and management of waste lead-acid batteries: A mini-review.

Science.gov (United States)

Li, Malan; Liu, Junsheng; Han, Wei

2016-04-01

As a result of the wide application of lead-acid batteries to be the power supplies for vehicles, their demand has rapidly increased owing to their low cost and high availability. Accordingly, the amount of waste lead-acid batteries has increased to new levels; therefore, the pollution caused by the waste lead-acid batteries has also significantly increased. Because lead is toxic to the environment and to humans, recycling and management of waste lead-acid batteries has become a significant challenge and is capturing much public attention. Various innovations have been recently proposed to recycle lead and lead-containing compounds from waste lead-acid batteries. In this mini-review article, different recycling techniques for waste lead-acid batteries are highlighted. The present state of such recycling and its future perspectives are also discussed. We hope that this mini-review can provide useful information on recovery and recycling of lead from waste lead-acid batteries in the field of solid waste treatment. © The Author(s) 2016.
Blood lead levels among rural Thai children exposed to lead-acid batteries from solar energy conversion systems.

Science.gov (United States)

Swaddiwudhipong, Witaya; Tontiwattanasap, Worawit; Khunyotying, Wanlee; Sanreun, Cherd

2013-11-01

We evaluate blood lead levels among Thai children to determine if exposure to lead-acid batteries is associated with elevated blood lead levels (EBLL). We screened 254 children aged 1-14 years old from 2 rural Thai villages for blood lead levels. We also screened 18 of 92 houses in these 2 villages for the presence of environmental lead. The overall prevalence of EBLL (> or = 10 microg/dl) was 43.3% and the mean lead level among study subjects was 9.8 +/- 5.1 microg/dl. The blood lead levels significantly decreased with increasing age. Fifty point eight percent of children who lived in a house with vented lead-acid batteries had EBLL while 23.3% of children who lived in a house without vented lead-acid batteries had EBLL. Multiple logistic regression analysis revealed a significant positive association between the presence of vented lead-acid batteries and EBLL, after adjusting for other variables. Forty-two point nine percent of house floor dust samples collected near the batteries had elevated lead levels, 7.1% of house floor dust samples collected from other areas in the house had elevated lead levels and 0% of the house floor dust samples collected in houses without vented lead-acid batteries had elevated lead levels. In the sampled houses with vented lead-acid batteries, lead contamination was found in the drinking-water kept in household containers, but not in the tap water or other village sources of water. Improper care and placement of vented lead-acid batteries can result in lead contamination in the home environment causing EBLL in exposed children.
Monitoring sealed automotive lead-acid batteries by sparse ...

Indian Academy of Sciences (India)

Unknown

knowledge of its internal resistance, which could be estimated from electrochemical ... rechargeable battery market and, in terms of value, the present world market for lead-acid ... the importance of a suitable battery monitoring and management will increase even .... automobiles to monitor the SOH of lead-acid battery bank.
Lead identification in soil surrounding a used lead acid battery smelter area in Banten, Indonesia

International Nuclear Information System (INIS)

Adventini, N; Santoso, M; Lestiani, D D; Syahfitri, W Y N; Rixson, L

2017-01-01

A used lead acid battery smelter generates particulates containing lead that can contaminate the surrounding environment area. Lead is a heavy metal which is harmful to health if it enters the human body through soil, air, or water. An identification of lead in soil samples surrounding formal and informal used lead acid battery smelters area in Banten, Indonesia using EDXRF has been carried out. The EDXRF accuracy and precision evaluated from marine sediment IAEA 457 gave a good agreement to the certified value. A number of 16 soil samples from formal and informal areas and 2 soil samples from control area were taken from surface and subsurface soils. The highest lead concentrations from both lead smelter were approximately 9 folds and 11 folds higher than the reference and control samples. The assessment of lead contamination in soils described in C f index was in category: moderately and strongly polluted by lead for formal and informal lead smelter. Daily lead intake of children in this study from all sites had exceeded the recommended dietary allowance. The HI values for adults and children living near both lead smelter areas were greater than the value of safety threshold 1. This study finding confirmed that there is a potential health risk for inhabitants surrounding the used lead acid battery smelter areas in Banten, Indonesia. (paper)
Experimental lead intoxication in dogs: a comparison of blood lead and urinary delta-aminolevulinic acid following intoxication and chelation therapy.

Science.gov (United States)

Green, R A; Selby, L A; Zumwalt, R W

1978-01-01

Intravenous lead administration to dogs produced an acute syndrome of lead intoxication charcterized by depression, vomiting, anorexia and weight loss. The effect of chelation therapy with calcium disodium ethylene diamine tetraacetate, penicillamine or both was determined by serially monitoring changes in blood lead and urine delta-aminolevulinic acid. Following therapy, blood lead values were significantly lower in chelated dogs than non-treated lead exposed dogs on days 7 and 10. Urine delta-aminolevulinic acid at day 7 was significantly higher in untreated lead exposed dogs than in other groups. There was no significant difference in blood lead or urine delta-aminolevulinic acid between lead intoxicated dogs which underwent the indicated chelation therapy protocols. There was, however, a trend for higher urinary delta-aminolevulinic acid excretion in those intoxicated dogs undergoing calcium disodium ethylene diamine tetraacetate therapy as opposed to those undergoing penicilamine therapy. There was no significant correlation between blood lead and urinary delta-aminolevulinic acid previous to lead exposure. However, after lead exposure significant correlation was present at days 4, 7, 10 and 14. Certain lead exposed dogs following chelation therapy were noted to have normal blood lead levels but elevated urinary delta-aminolevulinic acid suggesting that blood lead does not always correlate with metabolic effects of lead in the body. Urinary delta-aminolevulinic acid was therefore recommended as an additional laboratory parameter which improved assessment of lead exposure in dogs, particularly in determining adequacy of chelation therapy. PMID:667707
Influence of acid diffusion on the performance of lead-acid cells

Energy Technology Data Exchange (ETDEWEB)

Kappus, W.; Bohmann, J.

1983-11-01

A model for the discharge performance of the lead-acid cell is proposed. Diffusion of acid into the porous electrodes, which is connected with diffusional polarization, is considered as the principal factor in the transport process. The end of discharge is determined either by acid depletion inside the electrodes or by exhaustion of the active material, where utilization of the active material as a function of the acid density and the specific current is determined from empirical expressions. Curves of diffusional polarizations as a function of the discharge time are presented. Calculated discharge capacities show the influence of various parameters such as electrode thickness, current, and acid density. Tubular and pasted plates are considered.
Lead isotope results of acid leaching experiments on acid volcanics and black shales in an ore environment

International Nuclear Information System (INIS)

Gulson, B.L.

1977-01-01

In the volcanogenic Woodlawn Cu-Pb-Zn deposit, where pyrite is the dominant sulphide phase in the ore and a ubiquitous mineral in the host volcanics and shales, leaching experiments using HNO 3 -HCl to overcome the ore/rock lead dominance, resulted in highly complex lead isotopic data, dependent mainly on the original lead concentration in the rock. For samples with higher (> 5 ppm) lead concentrations, the acid leaches are less radiogenic than the rocks or residues whereas for samples with 15 ppm lead, the data arrays are those expected for a dominance of ore/rock lead. In all except the very high lead samples (> 100 ppm), lead is derived from sources other than sulphides. Furthermore, in only the highest lead sample is the acid leach isotopic value compatible with that of the ore lead. As found in previous leaching investigations, the dominant component of lead and uranium is extracted in the acid leach. Acid-leaching experiments of this type may have possible applications in prospecting for basemetal sulphides. (auth.)
Lead/acid batteries in systems to improve power quality

Science.gov (United States)

Taylor, P.; Butler, P.; Nerbun, W.

Increasing dependence on computer technology is driving needs for extremely high-quality power to prevent loss of information, material, and workers' time that represent billions of dollars annually. This cost has motivated commercial and Federal research and development of energy storage systems that detect and respond to power-quality failures in milliseconds. Electrochemical batteries are among the storage media under investigation for these systems. Battery energy storage systems that employ either flooded lead/acid or valve-regulated lead/acid battery technologies are becoming commercially available to capture a share of this emerging market. Cooperative research and development between the US Department of Energy and private industry have led to installations of lead/acid-based battery energy storage systems to improve power quality at utility and industrial sites and commercial development of fully integrated, modular battery energy storage system products for power quality. One such system by AC Battery Corporation, called the PQ2000, is installed at a test site at Pacific Gas and Electric Company (San Ramon, CA, USA) and at a customer site at Oglethorpe Power Corporation (Tucker, GA, USA). The PQ2000 employs off-the-shelf power electronics in an integrated methodology to control the factors that affect the performance and service life of production-model, low-maintenance, flooded lead/acid batteries. This system, and other members of this first generation of lead/acid-based energy storage systems, will need to compete vigorously for a share of an expanding, yet very aggressive, power quality market.
The influence of acid diffusion on the performance of lead-acid cells

Science.gov (United States)

Kappus, W.; Bohmann, J.

1983-11-01

A model for the discharge performance of the lead-acid cell is proposed. Diffusion of acid into the porous electrodes, which is connected with diffusio Curves of diffusional polarizations as a function of the discharge time are presented. Calculated discharge capacities show the influence of various pa
Changing corporate culture within the European lead/acid battery industry

International Nuclear Information System (INIS)

Mayer, M.G.

1994-01-01

Recent economic and political factors have had a strong influence on the lead/acid battery industry in both West and East Europe. Since the publication in 1989 by Batteries International and the Lead Development Association of a map of European battery factories, the number of battery companies has declined. By 1992, a significant shift had taken place in the share of the lead/acid battery market in Europe with the result that a few companies came to influence a major proportion of battery production and sales. The reasons for this relatively fast structural change are examined. Under the pressure from continuing internal and external forces, likely outcomes for battery business in Europe are proposed as the lead/acid industry changes to meet new challenges. (orig.)
Abolition Of The Lead-Acid Battery Consumption Tax Is Suggested

Institute of Scientific and Technical Information of China (English)

2016-01-01

Zhang Tianren,an NPC representative and chairman of Tianneng Group suggests cessation or deferment in the collection or differentiated collection of lead-acid battery consumption taxes.Lead-acid batteries play a fundamental role in China’s transport,communications,power generation and wind energy storage,smart grid
Residual learning rates in lead-acid batteries: Effects on emerging technologies

International Nuclear Information System (INIS)

Matteson, Schuyler; Williams, Eric

2015-01-01

The low price of lead-acid, the most popular battery, is often used in setting cost targets for emerging energy storage technologies. Future cost reductions in lead acid batteries could increase investment and time scales needed for emerging storage technologies to reach cost-parity. In this paper the first documented model of cost reductions for lead-acid batteries is developed. Regression to a standard experience curve using 1989–2012 data yield a poor fit, with R 2 values of 0.17 for small batteries and 0.05 for larger systems. To address this problem, battery costs are separated into material and residual costs, and experience curves developed for residual costs. Depending on the year, residual costs account for 41–86% of total battery cost. Using running-time averages to address volatility in material costs, a 4-year time average experience curve for residual costs yield much higher R 2 , 0.78 for small and 0.74 for large lead-acid batteries. The learning rate for residual costs in lead-acid batteries is 20%, a discovery with policy implications. Neglecting to consider cost reductions in lead-acid batteries could result in failure of energy storage start-ups and public policy programs. Generalizing this result, learning in incumbent technologies must be understood to assess the potential of emerging ones. -- Highlights: •We analyze potential cost reductions in lead-acid batteries. •Modified experience curve for non-material costs gives good empirical fit. •Historical learning rate for non-material costs from 1985–2012 is 19–24%. •Progress in incumbent technology raises barrier to new entrants
Preventive maintenance basis: Volume 24 -- Battery -- flooded lead-acid (lead-calcium, lead antimony, plante). Final report

International Nuclear Information System (INIS)

Worledge, D.; Hinchcliffe, G.

1997-12-01

US nuclear power plants are implementing preventive maintenance (PM) tasks with little documented basis beyond fundamental vendor information to support the tasks or their intervals. The Preventive Maintenance Basis project provides utilities with the technical basis for PM tasks and task intervals associated with 40 specific components such as valves, electric motors, pumps, and HVAC equipment. This document provides a program of preventive maintenance tasks suitable for application to flooded lead-acid batteries. The PM tasks that are recommended provide a cost-effective way to intercept the causes and mechanisms that lead to degradation and failure. They can be used in conjunction with material from other sources, to develop a complete PM program or to improve an existing program. This document provides a program of preventive maintenance (PM) tasks suitable for application to flooded lead-acid batteries. The PM tasks that are recommended provide a cost-effective way to intercept the causes and mechanisms that lead to degradation and failure. They can be used, in conjunction with material from other sources, to develop a complete PM program or to improve an existing program. Users of this information will be utility managers, supervisors, system engineers, craft technicians, and training instructors responsible for developing, optimizing, or fine-tuning PM programs
Association of Lead Exposure, Serum Uric Acid and Parameters of Renal Function in Nigerian Lead-Exposed Workers

Directory of Open Access Journals (Sweden)

DD Alasia

2010-09-01

Full Text Available Background: The presence of hyperuricemia and renal function impairment, especially in the absence of urate stone formation is strongly suggestive of lead nephropathy. The evaluation of this association is essential in areas where lead exposure is still prevalent and uncontrolled. Objective: To determine the relationship between serum uric acid and renal function indices in lead-exposed workers. Methods: A cross-sectional study of 190 adults with occupational lead exposure and 80 adults (comparison group, matched for age and sex was performed in Port Harcourt, South-south Nigeria. Blood lead was used as the biomarker of lead exposure while serum urea, serum creatinine, urine albumin (using urine albumin:creatinine ratio, estimated glomerular filtration rate (GFR and serum uric acid were the renal function indices measured. Results: Occupationally lead-exposed subjects had a significantly (p = 0.008 higher mean±SD blood lead levels (50.37±24.58 μg/dL than the comparison group (41.40±26.85. The mean±SD serum urea (8.6±2.3 mg/dL, creatinine (1.0±0.2 mg/dL and serum uric acid (4.6±1.2 mg/dL were significantly (p < 0.01 higher in the study subjects than the comparison group (7.6±2.4, 0.9±0.2, and 3.9±1.1 mg/dL, respectively. The mean±SD creatinine clearance was significantly (p = 0.002 lower in the study subjects than the comparison group (98.9±21.3 vs. 108.2±25.2 mL/min/1.72 m2. Serum uric acid level correlated positively with serum creatinine (r = 0.134 and negatively with GFR (r = ‑0.151. Conclusion: People with occupational lead exposure are at risk of developing hyperuricemia and renal impairment.
Recycling of spent lead/acid batteries. The case of Greece

International Nuclear Information System (INIS)

Zabaniotou, A.; Kouskoumvekaki, E.; Sanopoulos, D.

1999-01-01

In this study, the application of modern recycling technologies in accordance with the European and Greek legislation, aiming at the recovery of lead, polypropylene and sulfuric acid from spent lead (Pb)/acid batteries, is presented. The present state of their disposal and exploitation is also depicted. The international situation is reviewed, the general trends are marked and the main technologies related to lead/acid battery treatment are reported. General recommendations are given regarding the collection of spent batteries and the installation of a recycling plant in Greece. A sensitivity analysis is carried out in order to define the most significant parameters affecting the viability of a recycling scheme. The present study proves that a possible installation of a Pb/acid batteries recycling process unit, treating 17 000 t/year (estimated total quantity) and situated in the industrial area of the greater Athens region, seems to be economically profitable. The already existing operation of small-scale battery recycling plants, common in small countries, should be discouraged as they demonstrate a rather not environmentally acceptable recycling operation
Elution of lead from lead zirconate titanate ceramics to acid rain

Science.gov (United States)

Tsurumi, Takaaki; Takezawa, Shuhei; Hoshina, Takuya; Takeda, Hiroaki

2017-10-01

The amount of lead that eluted from lead zirconate titanate (PZT) ceramics to artificial acid rain was evaluated. Four kinds of PZT ceramics, namely, pure PZT at MPB composition, CuO-added PZT, PZT with 10 mol % substitution of Ba for Pb, and CuO-added PZT with 10 mol % substitution of Ba for Pb, were used as samples of the elution test. These PZT ceramics of 8 mm2 and 1.1-1.2 mm thickness were suspended in 300 ml of H2SO4 solution of pH 4.0. The concentration of lead eluted from PZT was in the range from 0.2 to 0.8 ppm. It was found that both liquid phase formation by the addition of CuO and the substitution of Ba for Pb were effective to reduce the amount of lead that eluted. By fitting the leaching out curve with a classical equation, a master curve assuming no sampling effect was obtained. The lead concentration evaluated from the amount of lead that eluted from a commercial PZT plate to H2SO4 solution of pH 5.3 was almost the same as the limit in city water. It is concluded that PZT is not harmful to health and the environment and the amount of lead that eluted from PZT can be controlled by modifying PZT composition.
The impact of the new 36 V lead-acid battery systems on lead consumption

Science.gov (United States)

Prengaman, R. David

The production of vehicles utilizing 36 V battery systems has begun with the introduction of the Toyota Crown. Other vehicles with 36 V batteries are in the near horizon. These vehicles may contain single or dual battery systems. These vehicles will most likely contain valve-regulated lead-acid (VRLA) batteries. The battery systems developed to date utilize significantly more lead than conventional 12 V batteries. This paper will evaluate the different proposed 36 V battery systems and estimate the lead requirements for each of the competing systems. It will also project the penetration of and resultant increased lead usage of these new batteries into the future.
The lead-acid eloflux cell. Research tool and candidate for advanced batteries

Energy Technology Data Exchange (ETDEWEB)

Kullmeine, U.; Kappus, W.

1982-12-01

The discharge capacity of usual lead-acid cells is limited by several mechanisms among which acid depletion is the most incisive. It is shown that the use of the so-called eloflux principle which is characterized by the flow of electrolyte through the porous electrodes, allows a significant deepe discharge and that by avoiding acid depletion the study of the other limiting processes and their functional dependence on the discharge conditions is possible. From the results it is concluded that an eloflux lead-acid cell is a promising candidate for advanced batteries with high energy density and performance.
Reversible surface binding of cadmium and lead by lactic acid and bifidobacteria.

Science.gov (United States)

Teemu, Halttunen; Seppo, Salminen; Jussi, Meriluoto; Raija, Tahvonen; Kalle, Lertola

2008-07-15

Extensive cadmium and lead contamination of water has been reported to occur locally as a result of human activities. Lactic acid bacteria have been reported to remove cadmium and lead from water. The aim of this work was to clarify the mechanisms of cadmium and lead removal from water. In addition, the effect of other metals, reversibility of binding and recyclability of the biomass was assessed. Based on our earlier data, the two most promising lactic acid bacteria, Lactobacillus fermentum ME3 and Bifidobacterium longum 46, were selected for these experiments. The results showed that the presence of other cationic metals and blocking of carboxyl and phosphoryl groups reduced cadmium and lead removal. These results suggest involvement of electrostatic interactions in cadmium and lead removal, and support our earlier findings. Transmission electron micrographs showed large deposits of lead on the bacterial surface suggesting formation of metallic lead precipitates. Both cadmium and lead removal were reversible processes established by full recovery of removed metal after desorption with dilute solutions of EDTA and HNO(3). Resorption capacity of both biomasses tested was reduced after regeneration with 10 mM EDTA and 15 mM HNO(3). Taken together, the results suggest involvement of several reversible mechanisms such as ion exchange and precipitation in cadmium and lead binding by lactic acid bacteria. The results show that specific lactic acid bacteria have the potential for removal of cadmium and lead from water although reduction in resorption capacity after regeneration of the biomass may form a problem. Since the studies so far have mainly focused on removal of single metals from pure water, metal removal in conditions of natural waters should be assessed in further experiments.
A low-cost lead-acid battery with high specific-energy

Indian Academy of Sciences (India)

Lightweight grids for lead-acid battery grids have been prepared from acrylonitrile butadiene styrene (ABS) copolymer followed by coating with lead. Subsequently, the grids have been electrochemically coated with a conductive and corrosion-resistant layer of polyaniline. These grids are about 75% lighter than those ...

A low-cost lead-acid battery with high specific-energy

Indian Academy of Sciences (India)

Unknown

Abstract. Lightweight grids for lead-acid battery grids have been prepared from acrylonitrile butadiene styrene (ABS) copolymer followed by coating with lead. Subsequently, the grids have been electro- chemically coated with a conductive and corrosion-resistant layer of polyaniline. These grids are about. 75% lighter than ...
Bipolar lead-acid battery for hybrid electric vehicles

NARCIS (Netherlands)

Schmal, D.; Saakes, M.; Veen, W.R. ter; Raadschelders, J.W.; Have, P.T.J.H. ten

2000-01-01

In hybrid electric vehicles (HEV) the requirements on batteries are very different from those for battery electric vehicles (BEV). A high power (bipolar) lead-acid battery could be a good alternative for other types of batteries under development for this application. It is potentially cheap and
Determination of SoH of Lead-Acid Batteries by Electrochemical Impedance Spectroscopy

Directory of Open Access Journals (Sweden)

Monika Kwiecien

2018-05-01

Full Text Available The aging mechanisms of lead-acid batteries change the electrochemical characteristics. For example, sulfation influences the active surface area, and corrosion increases the resistance. Therefore, it is expected that the state of health (SoH can be reflected through differentiable changes in the impedance of a lead-acid battery. However, for lead-acid batteries, no reliable SoH algorithm is available based on single impedance values or the spectrum. Additionally, the characteristic changes of the spectrum during aging are unknown. In this work, lead-acid test cells were aged under specific cycle regimes known as AK3.4, and periodic electrochemical impedance spectroscopy (EIS measurements and capacity tests were conducted. It was examined that single impedance values increased linearly with capacity decay, but with varying slopes depending on the pre-history of the cell and measurement frequency of impedance. Thereby, possible reasons for ineffective SoH estimation were found. The spectra were fitted to an equivalent electrical circuit containing, besides other elements, an ohmic and a charge-transfer resistance of the negative electrode. The linear increase of the ohmic resistance and the charge-transfer resistance were characterized for the performed cyclic aging test. Results from chemical analysis confirmed the expected aging process and the correlation between capacity decay and impedance change. Furthermore, the positive influence of charging on the SoH could be detected via EIS. The results presented here show that SoH estimation using EIS can be a viable technique for lead-acid batteries.
Acids with an equivalent taste lead to different erosion of human dental enamel.

Science.gov (United States)

Beyer, Markus; Reichert, Jörg; Bossert, Jörg; Sigusch, Bernd W; Watts, David C; Jandt, Klaus D

2011-10-01

The consumption of acidic soft drinks may lead to demineralization and softening of human dental enamel, known as dental erosion. The aims of this in vitro study were to determine: (i) if different acids with a similar sensorial acidic taste lead to different hardness loss of enamel and (ii) if the fruit acids tartaric, malic, lactic or ascorbic acid lead to less hardness loss of enamel than citric or phosphoric acid when their concentration in solution is based on an equivalent sensorial acidic taste. Enamel samples of non-erupted human third molars were treated with acidic solutions of tartaric (TA), malic (MA), lactic (LA), ascorbic (AA), phosphoric (PA) and citric (CA) acids with a concentration that gave an equivalent sensorial acidic taste. The acidic solutions were characterized by pH value and titratable acidity. Atomic force microscopy (AFM) based nanoindentation was used to study the nano mechanical properties and scanning electron microscopy (SEM) was used to study the morphology of the treated enamel samples and the untreated control areas, respectively. The investigated acids fell into two groups. The nano hardnesses of MA, TA and CA treated enamel samples (group I) were statistically significantly greater (penamel samples (group II). Within each group the nano hardness was not statistically significantly different (p>0.05). The SEM micrographs showed different etch prism morphologies depending on the acid used. In vitro, the acids investigated led to different erosion effects on human dental enamel, despite their equivalent sensorial acidic taste. This has not been reported previously. Copyright © 2011 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
Hybrid systems with lead-acid battery and proton-exchange membrane fuel cell

Science.gov (United States)

Jossen, Andreas; Garche, Juergen; Doering, Harry; Goetz, Markus; Knaupp, Werner; Joerissen, Ludwig

Hybrid systems, based on a lead-acid battery and a proton-exchange membrane fuel cell (PEMFC) give the possibility to combine the advantages of both technologies. The benefits for different applications are discussed and the practical realisation of such systems is shown. Furthermore a numerical model for such a hybrid system is described and results are shown and discussed. The results show that the combination of lead-acid batteries and PEMFC shows advantages in case of applications with high peak power requirements (i.e. electric scooter) and applications where the fuel cell is used as auxiliary power supply to recharge the battery. The high efficiency of fuel cells at partial load operation results in a good fuel economy for recharging of lead-acid batteries with a fuel cell system.
Lead/acid batteries for photovoltaic applications. Test results and modelling

Energy Technology Data Exchange (ETDEWEB)

Copetti, J B [CIEMAT, Inst. de Energias Renovables, Madrid (Spain); Chenlo, F [CIEMAT, Inst. de Energias Renovables, Madrid (Spain)

1994-01-01

This work presents the results of experiments carried out on lead/acid batteries during charge and discharge processes at different currents and temperatures, selected to a cover a large range of operating conditions, including those encountered in photovoltaic (PV) system applications. The results allow us to verify the relations among the battery external parameters (voltage, current, state-of-charge and temperature), the behaviour of the internal resistance, and to deduce a model that represents the discharge and charge processes, including the overcharge. Finally, normalized equations with respect to the battery capacity are proposed, which allow us to fix the values of parameters and hence the model is valid for any type and size of lead/acid battery. (orig.)
Lead-acid batteries for micro- and mild-hybrid applications

Science.gov (United States)

Valenciano, J.; Fernández, M.; Trinidad, F.; Sanz, L.

Car manufactures have announced the launch in coming months of vehicles with reduced emissions due to the introduction of new functions like stop-start and regenerative braking. Initial performance request of automotive lead-acid batteries are becoming more and more demanding and, in addition to this, cycle life with new accelerated ageing profiles are being proposed in order to determine the influence of the new functions on the expected battery life. This paper will show how different lead-acid battery technologies comply with these new demands, from an improved version of the conventional flooded SLI battery to the high performance of spiral wound valve-regulated lead-acid (VRLA) battery. Different approaches have been studied for improving conventional flooded batteries, i.e., either by the addition of new additives for reducing electrolyte stratification or by optimisation of the battery design to extend cycling life in partial state of charge conditions. With respect to VRLA technology, two different battery designs have been compared. Spiral wound design combines excellent power capability and cycle life under different depth of discharge (DoD) cycling conditions, but flat plate design outperform the latter in energy density due to better utilization of the space available in a prismatic enclosure. This latter design is more adequate for high end class vehicles with high electrical energy demand, whereas spiral wound is better suited for high power/long life demand of commercial vehicle. High temperature behaviour (75 °C) is rather poor for both designs due to water loss, and then VRLA batteries should preferably be located out of the engine compartment.
Dimensionally stable PbO{sub 2} electrodes for lead acid batteries

Energy Technology Data Exchange (ETDEWEB)

Devilliers, D.; Devos, B.; Groult, H. [Pierre et Marie Curie Univ., Paris (France). Laboratoire LI2C-Electrochimie

2007-07-15

Dimensionally stable anodes (DSAs) are regularly used in industrial electrolytic cells. The titanium substrate in these electrodes is covered by an electrocatalytic layer containing a precious metal oxide. The concept of PbO{sub 2}-dimensionally stable electrodes with a light metal substrate may also be applied to generators, particularly for bipolar lead acid batteries. However, one of the issues with bipolar lead-acid batteries is the stability of the bipolar electrode substrate, particularly on the side onto which the positive active mass is deposited. This article presented the results of a study that characterized the performance of different electrode substrates onto which PbO{sub 2} was electrodeposited using cyclic voltammetry performed with PbO{sub 2} in sulphuric acid. The article discussed the experiment with reference to the titanium substrates; modification of the substrates; x-ray diffraction; and cyclic voltammetry experiments with PbO{sub 2} electrodes. It also presented a discussion of the results. The study concluded that titanium covered by the mixed oxides layer titanium dioxide (TiO{sub 2})-tin dioxide (SnO{sub 2})-antimony oxide (Sb{sub 2}O{sub 3}) constitutes a suitable substrate for PbO{sub 2} electrodes. It can be used in lead acid batteries and allows the preparation of compact bipolar batteries. 36 refs., 1 tab., 5 figs.
Effect of antimony on lead-acid battery negative

International Nuclear Information System (INIS)

Mahato, B.K.; Bullock, K.R.; Strebe, J.L.; Wilkinson, D.F.

1985-01-01

The role of antimony on the lead-acid battery negative in terms of its effect on charge efficiency, its effect on gassing overpotential, its interactive influence with lignin expander in controlling the charge efficiency, and its retentive behavior or purging characteristics as SbH 3 in the overcharge gas stream was investigated. Linear potential sweep (LPS) cycling of Plante-type lead electrodes were used to determine the effect of antimony on gassing overpotential and to monitor its concentration either in the active material or the exit gas stream. Results showed a significant contribution of antimony in decreasing charge efficiency and an overwhelming role of lignin expander in suppressing the effect of antimony on charge efficiency. The critical lead-electrode potential for purging antimony from the electrode is close to -1275 mV (vs. Hg/Hg 2 SO 4 )
Humic Acids as Therapeutic Compounds in Lead Intoxication.

Science.gov (United States)

Krempaská, Klára; Vaško, Ladislav; Vašková, Janka

2016-01-01

The toxicity of lead and its compounds is well known, causing anemia by inhibiting the synthesis of porphyrins. The neurotoxic effects, particularly in the young, alter the structure of cell membranes and DNA. Chronic exposure to lead has adverse effects on the body by disrupting the mechanisms of energy production and tissue damage, in particular in its links with thiol groups and competition for binding sites with zinc. This review is therefore a description of the mechanism of lead toxicity as well as of possible interventions for the detoxification of the body. Part of the clinical intervention is the provision of chelates that form insoluble complexes with lead and eliminate the load in tissues. Most of these chelating agents have a number of side effects. It is therefore not surprising that active compounds with distinctive antioxidant and chelating properties are being sought after. The possibility of administering lower amounts, and the corresponding decrease in side effects, would be important for clinical practice. Both prospective studies and our initial studies on humic acids have highlighted positive effects based on their antioxidant and chelating properties.
Effect of acid rain pH on leaching behavior of cement stabilized lead-contaminated soil.

Science.gov (United States)

Du, Yan-Jun; Wei, Ming-Li; Reddy, Krishna R; Liu, Zhao-Peng; Jin, Fei

2014-04-30

Cement stabilization is a practical approach to remediate soils contaminated with high levels of lead. However, the potential for leaching of lead out of these stabilized soils under variable acid rain pH conditions is a major environmental concern. This study investigates the effects of acid rain on the leaching characteristics of cement stabilized lead contaminated soil under different pH conditions. Clean kaolin clay and the same soil spiked with 2% lead contamination are stabilized with cement contents of 12 and 18% and then cured for 28 days. The soil samples are then subjected to a series of accelerated leaching tests (or semi-dynamic leaching tests) using a simulated acid rain leachant prepared at pH 2.0, 4.0 or 7.0. The results show that the strongly acidic leachant (pH ∼2.0) significantly altered the leaching behavior of lead as well as calcium present in the soil. However, the differences in the leaching behavior of the soil when the leachant was mildly acidic (pH ∼4.0) and neutral (pH ∼7.0) prove to be minor. In addition, it is observed that the lead contamination and cement content levels can have a considerable impact on the leaching behavior of the soils. Overall, the leachability of lead and calcium is attributed to the stability of the hydration products and their consequent influence on the soil buffering capacity and structure. Copyright © 2014 Elsevier B.V. All rights reserved.
Studies of doped negative valve-regulated lead-acid battery electrodes

Czech Academy of Sciences Publication Activity Database

Micka, Karel; Calábek, M.; Bača, P.; Křivák, P.; Lábus, R.; Bilko, R.

2009-01-01

Roč. 191, č. 1 (2009), s. 154-158 ISSN 0378-7753 Institutional research plan: CEZ:AV0Z40400503 Keywords : lead-acid * negative electrode * sulfation suppression Subject RIV: CG - Electrochemistry Impact factor: 3.792, year: 2009
Eco-Balance analysis of the disused lead-acid-batteries recycling technology

Science.gov (United States)

Kamińska, Ewa; Kamiński, Tomasz

2017-10-01

The article presents the results of the eco-balance analysis of the disused lead-acid batteries recycling process. Test-dedicated technology offers the possibility to recover other elements, for example, polypropylene of the battery case or to obtain crystalline sodium sulphate. The life cycle assessment was made using ReCiPe and IMPACT2002 + methods. The results are shown as environmental points [Pt]. The results are shown in the environmental categories, specific for each of the methods grouped in the impact categories. 1 Mg of the processed srap was a dopted as the functional unit. The results of the analyses indicate that recycling processes may provide the environmental impact of recycling technology less harmful. Repeated use of lead causes that its original sources are not explored. Similarly, the use of granule production-dedicated polypropylene extracted from battery casings that are used in the plastics industry, has environmental benefits. Due to the widespread use of lead-acid batteries, the attention should be paid to their proper utilization, especially in terms of heavy metals, especially lead. According to the calculations, the highest level of environmental benefits from the use of lead from secondary sources in the production of new products, was observed in the refining process.
Eco-Balance analysis of the disused lead-acid-batteries recycling technology

Directory of Open Access Journals (Sweden)

Kamińska Ewa

2017-01-01

Full Text Available The article presents the results of the eco-balance analysis of the disused lead-acid batteries recycling process. Test-dedicated technology offers the possibility to recover other elements, for example, polypropylene of the battery case or to obtain crystalline sodium sulphate. The life cycle assessment was made using ReCiPe and IMPACT2002 + methods. The results are shown as environmental points [Pt]. The results are shown in the environmental categories, specific for each of the methods grouped in the impact categories. 1 Mg of the processed srap was a dopted as the functional unit. The results of the analyses indicate that recycling processes may provide the environmental impact of recycling technology less harmful. Repeated use of lead causes that its original sources are not explored. Similarly, the use of granule production-dedicated polypropylene extracted from battery casings that are used in the plastics industry, has environmental benefits. Due to the widespread use of lead-acid batteries, the attention should be paid to their proper utilization, especially in terms of heavy metals, especially lead. According to the calculations, the highest level of environmental benefits from the use of lead from secondary sources in the production of new products, was observed in the refining process.
Mass lead intoxication from informal used lead-acid battery recycling in dakar, senegal.

Science.gov (United States)

Haefliger, Pascal; Mathieu-Nolf, Monique; Lociciro, Stephanie; Ndiaye, Cheikh; Coly, Malang; Diouf, Amadou; Faye, Absa Lam; Sow, Aminata; Tempowski, Joanna; Pronczuk, Jenny; Filipe Junior, Antonio Pedro; Bertollini, Roberto; Neira, Maria

2009-10-01

Between November 2007 and March 2008, 18 children died from a rapidly progressive central nervous system disease of unexplained origin in a community involved in the recycling of used lead-acid batteries (ULAB) in the suburbs of Dakar, Senegal. We investigated the cause of these deaths. Because autopsies were not possible, the investigation centered on clinical and laboratory assessments performed on 32 siblings of deceased children and 23 mothers and on 18 children and 8 adults living in the same area, complemented by environmental health investigations. All 81 individuals investigated were poisoned with lead, some of them severely. The blood lead level of the 50 children tested ranged from 39.8 to 613.9 microg/dL with a mean of 129.5 microg/dL. Seventeen children showed severe neurologic features of toxicity. Homes and soil in surrounding areas were heavily contaminated with lead (indoors, up to 14,000 mg/kg; outdoors, up to 302,000 mg/kg) as a result of informal ULAB recycling. Our investigations revealed a mass lead intoxication that occurred through inhalation and ingestion of soil and dust heavily contaminated with lead as a result of informal and unsafe ULAB recycling. Circumstantial evidence suggested that most or all of the 18 deaths were due to encephalopathy resulting from severe lead intoxication. Findings also suggest that most habitants of the contaminated area, estimated at 950, are also likely to be poisoned. This highlights the severe health risks posed by informal ULAB recycling, in particular in developing countries, and emphasizes the need to strengthen national and international efforts to address this global public health problem.
Organic Acid Characteristics and Tolerance of Sengon (Paraserianthes falcataria L Nielsen to Lead

Directory of Open Access Journals (Sweden)

Luluk Setyaningsih

2012-12-01

Full Text Available This study aimed to find out the lead tolerance of sengon (Paraserianthes falcataria seedling based on growth performance, tolerance index, and secretion and accumulation of organic acids content. Seedlings were exposed to lead (Pb with the concentration of 0, 0.5, 1, 1.5, 5, and 10 mM in liquid nutrient culture for 4 days in order to investigate secretion and accumulation of oxalic, malic, and citric content, and for 15 days to examine growth performance and tolerance index. The result showed that tolerance index and growth performance of sengon seedling were insignificant (p > 0.05 to the rising of Pb concentration up to 1.5 mM with tolerance index at least 95%, and even caused an increase of fresh weight. However, the tolerance index and growth of sengon decreased significantly due to Pb exposure of 5 and 10 mM. Among the three organic acids, citrate was most dominant as compared to malate and oxalate. Secretion of citrate increased significantly (p < 0.05 with the rising concentration of Pb 0.5, 1 and 1.5 mM, reaching to 0.464, 0.540, and 0.587 µg mℓ-1, respectively, or rising according linear line (r = 0.9, p < 0.5. Citrate accumulation showed inconsistent pattern with the rising Pb exposure. The result suggested that sengon seedling have a slightly tolerance to lead by secretion of organic acid especially citric acid.Keywords: lead, sengon, tolerance, organic acid, liquid nutrient culture
Progress and challenges in bipolar lead-acid battery development

Science.gov (United States)

Bullock, Kathryn R.

1995-05-01

Bipolar lead-acid batteries have higher power densities than any other aqueous battery system. Predicted specific powers based on models and prototypes range from 800 kW/kg for 100 ms discharge times to 1.6 kW/kg for 10 s. A 48 V automotive bipolar battery could have 2 1/2 times the cold cranking rate of a monopolar 12 V design in the same size. Problems which have precluded the development of commercial bipolar designs include the instability of substrate materials and enhanced side reactions. Design approaches include pseudo-bipolar configurations, as well as true bipolar designs in planar and tubular configurations. Substrate materials used include lead and lead alloys, carbons, conductive ceramics, and tin-oxide-coated glass fibers. These approaches are reviewed and evaluated.
Contemporary Trends in Research and Development of Lead-Acid Batteries

Czech Academy of Sciences Publication Activity Database

Micka, Karel

2004-01-01

Roč. 8, - (2004), s. 932-933 ISSN 1432-8488 R&D Projects: GA ČR GA102/02/0794 Institutional research plan: CEZ:AV0Z4040901 Keywords : lead-acid batteries * electrical system * trends Subject RIV: CG - Electrochemistry Impact factor: 0.984, year: 2004
Selective Liquid-Liquid Extraction of Lead Ions Using Newly Synthesized Extractant 2-(Dibutylcarbamoylbenzoic Acid

Directory of Open Access Journals (Sweden)

Hossein Soltani

2015-12-01

Full Text Available A new carboxylic acid extractant, named 2-(dibutylcarbamoylbenzoic acid, is prepared and its potential for selective solvent extraction and recovery of lead ions from industrial samples was investigated. The slope analysis indicated that the lead ions are extracted by formation of 1:2 metal to ligand complexes. The effect of the parameters influencing the extraction efficiency including kind of the organic diluent, extractant concentration, type of the salt used for ionic strength adjustment, contact time and temperature was evaluated and discussed. Under optimized conditions (aqueous phase: 5 ml, initial lead concentration 1 × 10-4 M, pH 4, sodium chloride 0.1 M; organic phase: 5 ml dichloromethane, ligand concentration 0.05 M, a quantitative (75.2 ± 0.8% and highly selective extraction of lead ions in the presence of zinc, nickel, cobalt and cadmium ions (each 1 × 10-4 M was achieved, after 20 min. magnetically stirring of the phases, at 25 °C. The extracted lead ions were stripped from the organic phase by diluted nitric acid (0.1 M solution. The proposed method was successfully applied for separation of lead from industrial samples. The study of the effect of temperature allowed evaluating the thermodynamic parameters of the extraction process of lead ions by the studied extractant into dichloromethane.
Fuzzy Control of a Lead Acid Battery Charger

Directory of Open Access Journals (Sweden)

A. DAOUD

2005-03-01

Full Text Available In this paper, an alternative battery charging control technique based on fuzzy logic for photovoltaic (PV applications is presented. A PV module is connected to a buck type DC/DC power converter and a microcontroller based unit is used to control the lead acid battery charging voltage. The fuzzy control is used due to the simplicity of implementation, robustness and independence from the complex mathematical representation of the battery. The usefulness of this control method is confirmed by experiments.

The possibility of using 5-aminolevulinic acid in lead phytoextraction process

Directory of Open Access Journals (Sweden)

Zbigniew Jarosz

2013-04-01

Full Text Available Studies conducted in the greenhouse involving a sunflower (Helianthus annuus L. grown in medium containing 200 mg Pb ∙ dm -3 which were designed to evaluate the impact of foliar nutrition with 5-aminolevulinic acid (5-ALA on the chemical composition of sunflower in reference to possible use of this plant in the process of induced phytoextraction. The study revealed from 4.8% to 34.1% increase in aboveground matter of sunflower which was sprayed by 5-ALA solution at concentrations of 0.01-0.1 ppm in comparison with plants grown in a medium containing 200 mg Pb ∙ dm -3 with no 5-ALA spraying. The sunflower leaves sprayed by 5-ALA solution contained from 3.78% to 27.1% more lead in comparison to plants not sprayed by this agent. As well as remarkable decrease in lead content from 17.4 to 33.4% was recorded in the roots of sunflower sprayed by 5-ALA solution. The lead content in plant shoots was independent from foliar application of 5-aminolevulinic acid
Dynamics of three organic acids (malic, acetic and succinic acid) in sunflower exposed to cadmium and lead.

Science.gov (United States)

Niu, Zhixin; Li, Xiaodong; Sun, Lina; Sun, Tieheng

2013-01-01

Sunflower (Helianthus annuus L.) has been considered as a good candidate for bioaccumulation of heavy metals. In the present study, sunflower was used to enrich the cadmium and lead in sand culture during 90 days. Biomass, Cd and Pb uptake, three organic acids and pH in cultures were investigated. Results showed that the existence of Cd and Pb showed different interactions on the organic acids exudation. In single Cd treatments, malic and acetic acids in Cd10 showed an incremental tendency with time. In the mixed treatments of Cd and Pb, malic acids increased when 10 and 40 mg x L(-1) Cd were added into Pb50, but acetic acids in Pb50 were inhibited by Cd addition. The Cd10 supplied in Pb10 stimulated the secretion of malic and succinic acids. Moreover, the Cd or Pb uptake in sunflower showed various correlations with pH and some organic acids, which might be due to the fact that the Cd and Pb interfere with the organic acids secretion in rhizosphere of sunflower, and the changes of organic acids altered the form and bioavailability of Cd and Pb in cultures conversely.
A novel flow battery: A lead acid battery based on an electrolyte with soluble lead(II). Part IX: Electrode and electrolyte conditioning with hydrogen peroxide

Science.gov (United States)

Collins, John; Li, Xiaohong; Pletcher, Derek; Tangirala, Ravichandra; Stratton-Campbell, Duncan; Walsh, Frank C.; Zhang, Caiping

Extended cycling of a soluble lead acid battery can lead to problems due to an imbalance in the coulombic efficiency leading to deposits of Pb and PbO2 on the electrodes. Periodic addition of hydrogen peroxide to the electrolyte of the soluble lead acid flow battery largely overcomes several operational problems seen during extended cycling, using a 10 cm × 10 cm parallel plate flow cell. It is shown that this treatment greatly extends the number of cycles that can be achieved with a reasonable energy-, voltage-, and charge efficiency of 54-66%, 71%, and 77-91%.
A novel flow battery: A lead acid battery based on an electrolyte with soluble lead(II). Part IX: Electrode and electrolyte conditioning with hydrogen peroxide

Energy Technology Data Exchange (ETDEWEB)

Collins, John; Stratton-Campbell, Duncan [C-Tech Innovation Ltd., Capenhurst, Chester CH1 6EH (United Kingdom); Li, Xiaohong; Tangirala, Ravichandra; Walsh, Frank C.; Zhang, Caiping [Energy Technology Research Group, School of Engineering Sciences, University of Southampton, Highfield, University Road, Southampton SO17 1BJ (United Kingdom); Pletcher, Derek [Electrochemistry and Surface Science Group, School of Chemistry, University of Southampton, Southampton SO17 1BJ (United Kingdom)

2010-05-01

Extended cycling of a soluble lead acid battery can lead to problems due to an imbalance in the coulombic efficiency leading to deposits of Pb and PbO2 on the electrodes. Periodic addition of hydrogen peroxide to the electrolyte of the soluble lead acid flow battery largely overcomes several operational problems seen during extended cycling, using a 10 cm x 10 cm parallel plate flow cell. It is shown that this treatment greatly extends the number of cycles that can be achieved with a reasonable energy-, voltage-, and charge efficiency of 54-66%, 71%, and 77-91%. (author)
Simultaneous Removal of Lindane, Lead and Cadmium from Soils by Rhamnolipids Combined with Citric Acid

Science.gov (United States)

Long, Tao; Ying, Rongrong; Ye, Mao; Zhang, Shengtian; Li, Qun; Zhou, Yan; Lin, Yusuo

2015-01-01

This study investigated the performance of rhamnolipids-citric acid mixed agents in simultaneous desorption of lindane and heavy metals from soils. The capacity of the mixed agents to solubilize lindane, lead and cadmium in aqueous solution was also explored. The results showed that the presence of citric acid greatly enhanced the solubilization of lindane and cadmium by rhamnolipids. A combined effect of the mixed agents on lindane and heavy metals removal from soils was observed. The maximum desorption ratios for lindane, cadmium and lead were 85.4%, 76.4% and 28.1%, respectively, for the mixed agents containing 1% rhamnolipidsand 0.1 mol/L citric acid. The results also suggest that the removal efficiencies of lead and cadmium were strongly related to their speciations in soils, and metals in the exchangeable and carbonate forms were easier to be removed. Our study suggests that the combining use of rhamnolipids and citric acid is a promising alternative to simultaneously remove organochlorine pesticides and heavy metals from soils. PMID:26087302
Unsaturated Fatty Acids Supplementation Reduces Blood Lead Level in Rats

Science.gov (United States)

Skoczyńska, Anna; Wojakowska, Anna; Nowacki, Dorian; Bobak, Łukasz; Turczyn, Barbara; Smyk, Beata; Szuba, Andrzej; Trziszka, Tadeusz

2015-01-01

Some dietary factors could inhibit lead toxicity. The aim of this study was to evaluate the effect of dietary compounds rich in unsaturated fatty acids (FA) on blood lead level, lipid metabolism, and vascular reactivity in rats. Serum metallothionein and organs' lead level were evaluated with the aim of assessing the possible mechanism of unsaturated FA impact on blood lead level. For three months, male Wistar rats that were receiving drinking water with (100 ppm Pb) or without lead acetate were supplemented per os daily with virgin olive oil or linseed oil (0.2 mL/kg b.w.) or egg derived lecithin fraction: “super lecithin” (50 g/kg b.w.). Mesenteric artery was stimulated ex vivo by norepinephrine (NE) administered at six different doses. Lecithin supplementation slightly reduced pressor responses of artery to NE. Lead administered to rats attenuated the beneficial effect of unsaturated FA on lipid metabolism and vascular reactivity to adrenergic stimulation. On the other hand, the super lecithin and linseed oil that were characterized by low omega-6 to omega-3 ratio (about 1) reduced the blood lead concentration. This effect was observed in lead poisoned rats (p < 0.0001) and also in rats nonpoisoned with lead (p < 0.05). PMID:26075218
Delta-aminolevulinic acid dehydratase (ALAD) polymorphism in lead exposed Bangladeshi children and its effect on urinary aminolevulinic acid (ALA)

Energy Technology Data Exchange (ETDEWEB)

Tasmin, Saira, E-mail: rimzim1612@yahoo.com [Department of Human Ecology, School of International Health, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Furusawa, Hana [Department of Human Ecology, School of International Health, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Ahmad, Sk. Akhtar [Department of Occupational and Environmental Health, Bangladesh Institute of Health Sciences, 125/1, Darus Salam, Mirpur, Dhaka 1216 (Bangladesh); Faruquee, M.H. [Department of Public Health, State University of Bangladesh, 77 Satmasjid Road, Dhanmondi, Dhaka 1205 (Bangladesh); Watanabe, Chiho [Department of Human Ecology, School of International Health, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

2015-01-15

Background and objective: Lead has long been recognized as a harmful environmental pollutant. People in developing countries like Bangladesh still have a higher risk of lead exposure. Previous research has suggested that the delta-aminolevulinic acid dehydratase (ALAD) genotype can modify lead toxicity and individual susceptibility. As children are more susceptible to lead-induced toxicity, this study investigated whether the ALAD genotype influenced urinary excretion of delta-aminolevulinic acid (U-ALA) among children exposed to environmental lead in Bangladesh. Methods: Subjects were elementary schoolchildren from a semi-urban industrialized area in Bangladesh. A total of 222 children were studied. Blood and urine were collected to determine ALAD genotypes, blood lead levels and urinary aminolevulinic acid (U-ALA). Results: The mean BPb level was 9.7 µg/dl for the study children. BPb was significantly positively correlated with hemoglobin (p<0.01). In total, allele frequency for ALAD 1 and 2 was 0.83 and 0.17 respectively. The mean U-ALA concentration was lower in ALAD1-2/2-2 carriers than ALAD1-1 carriers for boys (p=0.001). But for girls, U-ALA did not differ significantly by genotype (p=0.26). When U-ALA was compared by genotype at the same exposure level in a multiple linear regression analysis, boys who were ALAD1-2/2-2 carriers still had a lower level of U-ALA compared to ALAD1-1carriers. Conclusion: This study provides information about the influence of ALAD polymorphism and its association with U-ALA in Bangladeshi children. Our results indicate that the ALAD1-2/2-2 genotype may have a protective effect in terms of U-ALA for environmentally lead exposed boys. - Highlights: • High blood lead level for the environmentally exposed schoolchildren. • BPb was significantly correlated with U-ALA and Hb. • Effect of ALAD genotype on U-ALA is differed by sex. • Lower U-ALA in ALAD2 than ALAD1 carriers only for boys at same exposure.
Advanced valve-regulated lead-acid batteries for hybrid vehicle applications

Science.gov (United States)

Soria, M. L.; Trinidad, F.; Lacadena, J. M.; Sánchez, A.; Valenciano, J.

Future vehicle applications require the development of reliable and long life batteries operating under high-rate partial-state-of-charge (HRPSoC) working conditions. Work presented in this paper deals with the study of different design parameters, manufacturing process and charging conditions of spiral wound valve-regulated lead-acid (VRLA) batteries, in order to improve their reliability and cycle life for hybrid vehicle applications. Test results show that both electrolyte saturation and charge conditions have a strong effect on cycle life at HRPSoC performance, presumably because water loss finally accelerates battery failure, which is linked to irreversible sulphation in the upper part of the negative electrodes. By adding expanded graphite to the negative active mass formulation, increasing the electrolyte saturation degree (>95%) and controlling overcharge during regenerative braking periods (voltage limitation and occasional boosting) it is possible to achieve up to 220,000 cycles at 2.5% DOD, equivalent to 5500 capacity throughput. These results could make lead acid batteries a strong competitor for HEV applications versus other advanced systems such as Ni-MH or Li-ion batteries.
Electrochemical Studies of Lead Telluride Behavior in Acidic Nitrate Solutions

Directory of Open Access Journals (Sweden)

Rudnik E.

2015-04-01

Full Text Available Electrochemistry of lead telluride stationary electrode was studied in nitric acid solutions of pH 1.5-3.0. E-pH diagram for Pb-Te-H2O system was calculated. Results of cyclic voltammetry of Pb, Te and PbTe were discussed in correlation with thermodynamic predictions. Anodic dissolution of PbTe electrode at potential approx. -100÷50 mV (SCE resulted in tellurium formation, while above 300 mV TeO2 was mainly produced. The latter could dissolve to HTeO+2 under acidic electrolyte, but it was inhibited by increased pH of the bath.
Lifetime modelling of lead acid batteries

Energy Technology Data Exchange (ETDEWEB)

Bindner, H.; Cronin, T.; Lundsager, P.

2005-04-01

The performance and lifetime of energy storage in batteries are an important part of many renewable based energy systems. Not only do batteries impact on the system performance but they are also a significant expenditure when considering the whole life cycle costs. Poor prediction of lifetime can, therefore, lead to uncertainty in the viability of the system in the long term. This report details the work undertaken to investigate and develop two different battery life prediction methodologies with specific reference to their use in hybrid renewable energy systems. Alongside this, results from battery tests designed to exercise batteries in similar modes to those that they experience in hybrid systems have also been analysed. These have yielded battery specific parameters for use in the prediction software and the first results in the validation process of the software are also given. This work has been part of the European Union Benchmarking research project (ENK6-CT-2001-80576), funded by the European Union, the United States and Australian governments together with other European states and other public and private financing bodies. The project has concentrated on lead acid batteries as this technology is the most commonly used. Through this work the project partner institutions have intended to provide useful tools to improve the design capabilities of organizations, private and public, in remote power systems. (au)
Influence of residual elements in lead on oxygen- and hydrogen-gassing rates of lead-acid batteries

Science.gov (United States)

Lam, L. T.; Ceylan, H.; Haigh, N. P.; Lwin, T.; Rand, D. A. J.

Raw lead materials contain many residual elements. With respect to setting 'safe' levels for these elements, each country has its own standard, but the majority of the present specifications for the lead used to prepare battery oxide apply to flooded batteries that employ antimonial grids. In these batteries, the antimony in the positive and negative grids dominates gassing characteristics so that the influence of residual elements is of little importance. This is, however, not the case for valve-regulated lead-acid (VRLA) batteries, which use antimony-free grids and less sulfuric acid solution. Thus, it is necessary to specify 'acceptable' levels of residual elements for the production of VRLA batteries. In this study, 17 elements are examined, namely: antimony, arsenic, bismuth, cadmium, chromium, cobalt, copper, germanium, iron, manganese, nickel, selenium, silver, tellurium, thallium, tin, and zinc. The following strategy has been formulated to determine the acceptable levels: (i) selection of a control oxide; (ii) determination of critical float, hydrogen and oxygen currents; (iii) establishment of a screening plan for the elements; (iv) development of a statistical method for analysis of the experimental results. The critical values of the float, hydrogen and oxygen currents are calculated from a field survey of battery failure data. The values serve as a base-line for comparison with the corresponding measured currents from cells using positive and negative plates produced either from the control oxide or from oxide doped with different levels of the 17 elements in combination. The latter levels are determined by means of a screening plan which is based on the Plackett-Burman experimental design. Following this systematic and thorough exercise, two specifications are proposed for the purity of the lead to be used in oxide production for VRLA technology.
Health hazards of China's lead-acid battery industry: a review of its market drivers, production processes, and health impacts.

Science.gov (United States)

van der Kuijp, Tsering Jan; Huang, Lei; Cherry, Christopher R

2013-08-03

Despite China's leaded gasoline phase out in 2000, the continued high rates of lead poisoning found in children's blood lead levels reflect the need for identifying and controlling other sources of lead pollution. From 2001 to 2007, 24% of children in China studied (N = 94,778) were lead poisoned with levels exceeding 100 μg/L. These levels stand well above the global average of 16%. These trends reveal that China still faces significant public health challenges, with millions of children currently at risk of lead poisoning. The unprecedented growth of China's lead-acid battery industry from the electric bike, automotive, and photovoltaic industries may explain these persistently high levels, as China remains the world's leading producer, refiner, and consumer of both lead and lead-acid batteries.This review assesses the role of China's rising lead-acid battery industry on lead pollution and exposure. It starts with a synthesis of biological mechanisms of lead exposure followed by an analysis of the key technologies driving the rapid growth of this industry. It then details the four main stages of lead battery production, explaining how each stage results in significant lead loss and pollution. A province-level accounting of each of these industrial operations is also included. Next, reviews of the literature describe how this industry may have contributed to mass lead poisonings throughout China. Finally, the paper closes with a discussion of new policies that address the lead-acid battery industry and identifies policy frameworks to mitigate exposure.This paper is the first to integrate the market factors, production processes, and health impacts of China's growing lead-acid battery industry to illustrate its vast public health consequences. The implications of this review are two-fold: it validates calls for a nationwide assessment of lead exposure pathways and levels in China as well as for a more comprehensive investigation into the health impacts of the lead-acid
Role of ascorbic acid supplement in reducing oxidative stress and hepatotoxicity in lead intoxication

International Nuclear Information System (INIS)

Farooq, Y.; Hussain, M.M.; Aleem, S.B.

2013-01-01

Objective: The present study was conducted to measure the oxidative stress and hepatotoxicity in lead intoxicated sprague dawley rats with and without supplementation of ascorbic acid. Study Design: Randomized Control Trial. Place of Study: Physiology Department, Army Medical College, Rawalpindi. (From Oct 2007 to Sep 2008) Material and Methods: One hundred and five male rats (age, 90-120 days; weight 200 - 250 gm) were divided into three groups each having 35 rats. Rats of group 1 and group 2 were given weekly injections of sodium acetate (10 mg /kg body weight) and lead acetate (10 mg /kg body weight) respectively, whereas rats of group 3 were administered lead acetate(10 mg /kg body weight) through weekly injections and ascorbic acid in drinking water (500 mg/l). After 6 weeks, 4 ml of blood was drawn from each rat by cardiac puncture. The blood was allowed to clot and serum was separated for estimation of serum malondialdehyde (MDA) levels on spectrophotometer; and serum alanine aminotransferase (ALT) levels and aspartate aminotransferase (AST) levels on Merck Micorlab 200. Results: Lead intoxication of rats revealed that serum MDA levels were raised to 7.8 +- 0.48 micro mol/l (control, 3.2 +-0.39 micro mol/l), ALT levels to 76.26 +- 5.88 IU/l (control, 44.1 +- 3.26) and AST levels to 258.06 +- 13.30 IU/l (control, 156.2 +- 4.97). Ascorbic acid supplementation significantly lowered serum MDA levels (3.8 +- 0.34 micro mol/l), ALT levels (52.26 +-4.57 IU/l) and AST levels (188.13 +- 12.91 IU/l). Conclusion: Ascorbic acid supplementation ameliorates lead intoxication probably by reducing the oxidative stress, thus preventing the development of hepatotoxicity, but this amelioration is not equal to the control. (author)
Screening and assessment of solidification/stabilization amendments suitable for soils of lead-acid battery contaminated site.

Science.gov (United States)

Zhang, Zhuo; Guo, Guanlin; Teng, Yanguo; Wang, Jinsheng; Rhee, Jae Seong; Wang, Sen; Li, Fasheng

2015-05-15

Lead exposure via ingestion of soil and dust generally occurs at lead-acid battery manufacturing and recycling sites. Screening solidification/stabilization (S/S) amendments suitable for lead contaminated soil in an abandoned lead-acid battery factory site was conducted based on its chemical forms and environmental risks. Twelve amendments were used to immobilize the Pb in soil and assess the solidification/stabilization efficiency by toxicity leaching tests. The results indicated that three amendments, KH₂PO₄ (KP), KH₂PO₄:oyster shell power=1:1 (by mass ratio; SPP), and KH₂PO₄:sintered magnesia=1:1 (by mass ratio; KPM) had higher remediation efficiencies that led to a 92% reduction in leachable Pb with the addition of 5% amendments, while the acid soluble fraction of Pb (AS-Pb) decreased by 41-46% and the residual fraction (RS-Pb) increased by 16-25%. The S/S costs of the three selected amendments KP, SPP, and KPM could be controlled to $22.3 per ton of soil when the Pb concentration in soil ranged from 2000 to 3000 mg/kg. The results of this study demonstrated that KP, SPP, and KPM can effectively decrease bioavailability of Pb. These findings could provide basis for decision-making of S/S remediation of lead-acid battery contaminated sites. Copyright © 2015 Elsevier B.V. All rights reserved.
An overview of the development of lead/acid traction batteries for electric vehicles in India

Science.gov (United States)

Sivaramaiah, G.; Subramanian, V. R.

Electric vehicles (EVs) made an entry into the Indian scene quite recently in the area of passenger transportation, milk floats and other similar applications. The industrial EV market, with various models of fork-lift trucks and platform trucks already in wide use all over India, is a better understood application of EV batteries. The lead/acid traction batteries available in India are not of high-energy density. The best available indigenous lead/acid traction battery has an energy density ( C/5 rate) of 30 W h kg -1 as against 39 W h kg -1 available abroad. This paper reviews the developmental efforts relating to lead/acid traction batteries for electric vehicle applications in India, such as prototype road vehicles, commercial vehicles, rail cars, and locomotives. Due to the need for environmental protection and recognition of exhaustible, finite supplies of petroleum fuel, the Indian government is presently taking active interest in EV projects.
Separation of Rhenium from Lead-Rich Molybdenite Concentrate via Hydrochloric Acid Leaching Followed by Oxidative Roasting

Directory of Open Access Journals (Sweden)

Guanghui Li

2016-11-01

Full Text Available Lead-rich molybdenite is a typical rhenium-bearing molybdenum resource in China, which has not been efficiently utilized due to its high contents of lead and gangue minerals. In this study, hydrochloric acid was used for preliminarily removing lead and calcite from a lead-rich molybdenite concentrate. Oxidative roasting-ammonia leaching was then carried out for separation of rhenium and extraction of molybdenum. The hydrochloric acid leaching experiments revealed that 93.6% Pb and 97.4% Ca were removed when the leaching was performed at 95 °C for 10 min with HCl concentration of 8 wt. % and liquid-solid ratio of 5 (mL/g. The results of direct oxidative roasting indicated that 89.3% rhenium was volatilized from the raw concentrate after roasting at 600 °C for 120 min in air. In contrast, the rhenium volatilization was enhanced distinctly to 98.0% after the acid-leached concentrate (leaching residue was roasted at 550 °C for 100 min. By the subsequent ammonia leaching, 91.5% molybdenum was leached out from the calcine produced from oxidative roasting of the acid-leached concentrate, while only 79.3% Mo was leached from the calcine produced by roasting molybdenite concentrate without pretreatment.
Synthesis of uniform nano-structured lead oxide by sonochemical method and its application as cathode and anode of lead-acid batteries

International Nuclear Information System (INIS)

Karami, Hassan; Karimi, Mohammad Ali; Haghdar, Saeed

2008-01-01

This paper discusses the results of a research aimed at investigating the synthesis of nano-structured lead oxide through reaction of lead nitrate solution and sodium carbonate solution by the sonochemical method. At the first, lead carbonate was obtained in a synthesized solution and then, after filtration, it was calcinated at the temperature of 320 deg. C so that nano-structured lead oxide can be produced. The effects of different parameters on particle size and morphology of final lead oxide powder were optimized by a 'one at a time' method. The prepared lead oxide powder was characterized by scanning electron microscopy (SEM), transmission electron spectroscopy (TEM) and X-ray diffraction (XRD). Under optimum conditions, uniformed and homogeneous nano-structured lead oxide powder with more spongy morphology and particle size of 20-40 nm was obtained. The synthesized lead oxide, as anode and cathode of lead-acid batteries, showed an excellent discharge capacity (140 mA h/g)
Health hazards of China’s lead-acid battery industry: a review of its market drivers, production processes, and health impacts

Science.gov (United States)

2013-01-01

Despite China’s leaded gasoline phase out in 2000, the continued high rates of lead poisoning found in children’s blood lead levels reflect the need for identifying and controlling other sources of lead pollution. From 2001 to 2007, 24% of children in China studied (N = 94,778) were lead poisoned with levels exceeding 100 μg/L. These levels stand well above the global average of 16%. These trends reveal that China still faces significant public health challenges, with millions of children currently at risk of lead poisoning. The unprecedented growth of China’s lead-acid battery industry from the electric bike, automotive, and photovoltaic industries may explain these persistently high levels, as China remains the world’s leading producer, refiner, and consumer of both lead and lead-acid batteries. This review assesses the role of China’s rising lead-acid battery industry on lead pollution and exposure. It starts with a synthesis of biological mechanisms of lead exposure followed by an analysis of the key technologies driving the rapid growth of this industry. It then details the four main stages of lead battery production, explaining how each stage results in significant lead loss and pollution. A province-level accounting of each of these industrial operations is also included. Next, reviews of the literature describe how this industry may have contributed to mass lead poisonings throughout China. Finally, the paper closes with a discussion of new policies that address the lead-acid battery industry and identifies policy frameworks to mitigate exposure. This paper is the first to integrate the market factors, production processes, and health impacts of China’s growing lead-acid battery industry to illustrate its vast public health consequences. The implications of this review are two-fold: it validates calls for a nationwide assessment of lead exposure pathways and levels in China as well as for a more comprehensive investigation into the health
Eliminación del plomo por curado casero Lead elimination by traditional acidic curing

Directory of Open Access Journals (Sweden)

Luisa Torres-Sánchez

1999-11-01

Full Text Available Objetivo. Evaluar el curado ácido como medida preventiva para reducir el contenido de plomo en vasijas de barro vidriadas. Material y métodos. En 27 vasijas de barro procedentes de cuatro estados de México se determinó, mediante espectrofotometría de absorción atómica, el nivel de plomo residual, después de cuatro lavados con ácido acético al 3%. Resultados. El contenido de plomo en el ácido acético utilizado para lavar las vasijas disminuyó proporcionalmente con el número de lavados, aunque se conservó por arriba de los niveles permisibles (2.5-7.0 p.p.m.. Conclusiones. El curado ácido de piezas de barro no es una medida preventiva útil para reducir la exposición a plomo.Objective. To evaluate traditional acidic curing as a preventive method for reducing lead content of glazed ceramic ware. Material and methods. In 27 ceramic ware pieces from four states in Mexico, the level of residual lead was determined through atomic absorption spectrophotometry after four washings with acetic acid 3%. Results. The lead content of the vinegar washing diminished proportionally with the number of washings, although it remained highly above the permissible levels of this metal (2.5-7.0 p.p.m.. Conclusions. Traditional acidic curing of glazed ceramic ware is not a useful preventive measure for reducing lead exposure.
78 FR 15753 - Maintenance, Testing, and Replacement of Vented Lead-Acid Storage Batteries for Nuclear Power Plants

Science.gov (United States)

2013-03-12

...-Acid Storage Batteries for Nuclear Power Plants AGENCY: Nuclear Regulatory Commission. ACTION: Draft...-Acid Storage Batteries for Nuclear Power Plants.'' The draft guide describes methods that the NRC staff..., testing, and replacement of vented lead-acid storage batteries in nuclear power plants. DATES: Submit...

An inproved synthesis of 24- 13C-labeled bile acids using formyl esters and a modified lead tetraacetate procedure

International Nuclear Information System (INIS)

Tserng, K.Y.; Klein, P.D.

1977-01-01

An improved synthesis of 24- 13 C-labeled bile acids has been achieved using formyl derivatives of bile acids and a modified lead tetraacetate procedure. The formylated bile acids were degraded by lead tetraacetate and lithium chloride to formylated 23-chloronorcholanes in 72 to 83% yield. Formylated 23-chloronorcholanes were converted to nitriles in dimethylformamide, which were then hydrolyzed to obtain C-24 labeled bile acids in yield of 80 to 90% of labeled sodium cyanide used. This method results in a higher yield and a purer product with less manipulation than previously reported procedures for synthesis of labeled bile acids
A comparison of portable XRF and ICP-OES analysis for lead on air filter samples from a lead ore concentrator mill and a lead-acid battery recycler.

Science.gov (United States)

Harper, Martin; Pacolay, Bruce; Hintz, Patrick; Andrew, Michael E

2006-03-01

Personal and area samples for airborne lead were taken at a lead mine concentrator mill, and at a lead-acid battery recycler. Lead is mined as its sulfidic ore, galena, which is often associated with zinc and silver. The ore typically is concentrated, and partially separated, on site by crushing and differential froth flotation of the ore minerals before being sent to a primary smelter. Besides lead, zinc and iron are also present in the airborne dusts, together with insignificant levels of copper and silver, and, in one area, manganese. The disposal of used lead-acid batteries presents environmental issues, and is also a waste of recoverable materials. Recycling operations allow for the recovery of lead, which can then be sold back to battery manufacturers to form a closed loop. At the recycling facility lead is the chief airborne metal, together with minor antimony and tin, but several other metals are generally present in much smaller quantities, including copper, chromium, manganese and cadmium. Samplers used in these studies included the closed-face 37 mm filter cassette (the current US standard method for lead sampling), the 37 mm GSP or "cone" sampler, the 25 mm Institute of Occupational Medicine (IOM) inhalable sampler, the 25 mm Button sampler, and the open-face 25 mm cassette. Mixed cellulose-ester filters were used in all samplers. The filters were analyzed after sampling for their content of the various metals, particularly lead, that could be analyzed by the specific portable X-ray fluorescence (XRF) analyzer under study, and then were extracted with acid and analyzed by inductively coupled plasma optical emission spectroscopy (ICP-OES). The 25 mm filters were analyzed using a single XRF reading, while three readings on different parts of the filter were taken from the 37 mm filters. For lead at the mine concentrate mill, all five samplers gave good correlations (r2 > 0.96) between the two analytical methods over the entire range of found lead mass
Synthesis and application of a novel Cu/RGO@Pb alloy for lead-acid batteries

International Nuclear Information System (INIS)

Wu, Yumeng; Zhao, Ruirui; Zhou, Huawen; Zhang, Dejing; Zhao, Wei; Chen, Hongyu

2016-01-01

In this work, a novel Cu/RGO@Pb alloy was prepared successfully and tested in the simulated lead-acid battery environment. In preparing the novel alloy, Cu/RGO composite was firstly synthesized in order to increase the wettability of RGO to Pb, and then the composite was added to the molten lead to obtain the target alloy. Scanning electron microscope, energy dispersive spectrometer, X-ray diffraction as well as electrochemical measurements were employed to evaluate the performance of the obtained composite and alloy. Results show that the prepared Cu/RGO@Pb possessed higher oxygen evolution over-potential and lower hydrogen evolution over-potential than the contrast alloy, indicating this novel alloy was more suitable for using as positive grids in lead acid batteries. Moreover, the RGO additive could inhibit the formation of Pb(II) and Pb(IV) film on the surface of the alloy, which could enhance the deep-charge/discharge performance of the grids and improve the corrosion resistance.
Molecular dynamics of palmitic acid and lead palmitate in cross-linked linseed oil films: Implications from deuterium magnetic resonance for lead soap formation in traditional oil paintings.

Science.gov (United States)

Catalano, Jaclyn; Murphy, Anna; Yao, Yao; Zumbulyadis, Nicholas; Centeno, Silvia A; Dybowski, Cecil

2018-02-01

Many oil paintings, dating from the 15th century to the present, are affected by the formation of heavy-metal carboxylates (soaps) that alter the structural integrity and appearance of the works. Through transport phenomena not yet understood, free fatty acids formed from oils used as binders migrate through the paint film and react with heavy-metal ions that are constituents of pigments and/or driers, forming metal carboxylates. The local molecular dynamics of fatty acids and metal carboxylates are factors influencing material transport in these systems. We report temperature-dependent 2 H NMR spectra of palmitic acid and lead palmitate as pure materials, in cross-linked linseed oil films, and in a lead white linseed oil paint film as part of our broader research into metal soap formation. Local dynamics at the α carbon, at the terminal methyl group, and at the middle of the fatty acid chain were observed in specifically deuterated materials. Changes in the dynamic behavior with temperature were observed by the appearance of two species, a solid-like material and a liquid-like material. The relative amounts of the two phases and their deuterium NMR parameters indicate that the amount of liquid-like material and the local dynamics at that site increase with temperature. At the three locations along the chain and at all temperatures, there is a larger percentage of acyl chains of both palmitic acid and lead palmitate that are "mobile" or liquid-like in linseed oil films than there are in the pure materials. However, the percentage of liquid-like species is decreased in a lead white paint film, as compared to a linseed oil matrix. In addition, these experiments indicate that there is a larger percentage of liquid-like acyl chains of palmitic acid than of lead palmitate under identical conditions in these model paint systems. Copyright © 2017 Elsevier Inc. All rights reserved.
Electroplated reticulated vitreous carbon current collectors for lead-acid batteries: opportunities and challenges

Science.gov (United States)

Gyenge, Elod; Jung, Joey; Mahato, Basanta

Reticulated, open-cell structures based on vitreous carbon substrates electroplated with a Pb-Sn (1 wt.%) alloy were investigated as current collectors for lead-acid batteries. Scanning and backscattered electron microscopy, cyclic voltammetry, anodic polarization and flooded 2 V single-cell battery testing was employed to characterize the performance of the proposed collectors. A battery equipped with pasted electroplated reticulated vitreous carbon (RVC) electrodes of 137 cm 2 geometric area, at the time of manuscript submission, completed 500 cycles and over 1500 h of continuous operation. The cycling involved discharges at 63 A kg PAM-1 corresponding to a nominal 0.75 h rate and a positive active mass (PAM) utilization efficiency of 21%. The charging protocol was composed of two voltage limited (i.e. 2.6 V/cell), constant current steps of 35 and 9.5 A kg PAM-1, respectively, with a total duration of about 2 h. The charge factor was 1.05-1.15. The observed cycling behavior in conjunction with the versatility of electrodeposition to produce application-dependent optimized lead alloy coating thickness and composition shows promise for the development of lead-acid batteries using electroplated reticulated vitreous carbon collectors.
Poly(acrylic acid) modifying bentonite with in-situ polymerization for removing lead ions.

Science.gov (United States)

He, Y F; Zhang, L; Yan, D Z; Liu, S L; Wang, H; Li, H R; Wang, R M

2012-01-01

In this paper, a new kind of poly(acrylic acid) modified clay adsorbent, the poly(acrylic acid)/bentonite composite (PAA/HB) was prepared by in-situ polymerization, and utilized to remove lead(II) ions from solutions. The maximum adsorption of adsorbent is at pH 5 for metal ions, whereas the adsorption starts at pH 2. The effects of contact time (5-60 min), initial concentration of metal ions (200-1,000 mg/L) and adsorbent dosage (0.04-0.12 g/100 mL) have been reported in this article. The experimental data were investigated by means of kinetic and equilibrium adsorption isotherms. The kinetic data were analyzed by the pseudo-first-order and pseudo-second-order equation. The experimental data fitted the pseudo-second-order kinetic model very well. Langmuir and Freundlich isotherms were tried for the system to better understand the adsorption isotherm process. The maximal adsorption capacity of the lead(II) ions on the PAA/HB, as calculated from the Langmuir model, was 769.2 mg/g. The results in this study indicated that PAA/HB was an attractive candidate for removing lead(II) (99%).
Effect of polysulfone concentration on the performance of membrane-assisted lead acid battery

Directory of Open Access Journals (Sweden)

Ahmad Fauzi Ismail

2002-11-01

Full Text Available The application of lead acid battery in tropical countries normally faces the problem of water decomposition. This phenomenon is due to the factor of charge-discharge reaction in the battery and heat accumulation caused by hot tropical climate and heat generated from engine compartment. The objective of this study is to analyze the effect of polysulfone concentration on the performance of membrane-assisted lead-acid battery. Gas separation membranes, prepared through wet-dry phase inversion method and using various polysulfone concentrated formulations, were applied on the battery vent holes, for the purpose of preventing electrolyte from evaporating to the atmosphere. The best membrane, which retains the most electrolyte, will be chosen to be applied on the soon-to-be-developed “membrane-assisted maintenance- free battery”. This maintenance-free battery will need no topping up of deionized water every time the electrolyte level goes low.
An exploratory study of lead recovery in lead-acid battery lifecycle in US market: An evidence-based approach

International Nuclear Information System (INIS)

Genaidy, A.M.; Sequeira, R.; Tolaymat, T.; Kohler, J.; Rinder, M.

2008-01-01

Background: This research examines lead recovery and recycling in lead-acid batteries (LAB) which account for 88% of US lead consumption. We explore strategies to maximize lead recovery and recycling in the LAB lifecycle. Currently, there is limited information on recycling rates for LAB in the published literature and is derived from a single source. Therefore, its recycling efforts in the US has been unclear so as to determine the maximum opportunities for metal recovery and recycling in the face of significant demands for LAB particularly in the auto industry. Objectives: The research utilizes an evidence-based approach to: (1) determine recycling rates for lead recovery in the LAB product lifecycle for the US market; and (2) quantify and identify opportunities where lead recovery and recycling can be improved. Methods: A comprehensive electronic search of the published literature was conducted to gather information on different LAB recycling models and actual data used to calculate recycling rates based on product lifecycle for the US market to identify strategies for increasing lead recovery and recycling. Results: The electronic search yielded five models for calculating LAB recycling rates. The description of evidence was documented for each model. Furthermore, an integrated model was developed to identify and quantify the maximum opportunities for lead recovery and recycling. Results showed that recycling rates declined during the period spanning from 1999 to 2006. Opportunities were identified for recovery and recycling of lead in the LAB product lifecycle. Concluding remarks: One can deduce the following from the analyses undertaken in this report: (1) lead recovery and recycling has been stable between 1999 and 2006; (2) lead consumption has increased at an annual rate of 2.25%, thus, the values derived in this study for opportunities dealing with lead recovery and recycling underestimate the amount of lead in scrap and waste generated; and (3) the
Injury Surveillance and Safety Considerations for Large-Format Lead-Acid Batteries Used in Mining Applications.

Science.gov (United States)

Reyes, Miguel Angel; Novak, Thomas

2016-03-01

Large lead-acid batteries are predominantly used throughout the mining industry to power haulage, utility, and personnel-carrier vehicles. Without proper operation and maintenance, the use of these batteries can introduce mechanical and electrical hazards, particularly in the confined, and potentially dangerous, environment of an underground coal mine. A review of the Mine Safety and Health Administration accident/illness/injury database reveals that a significant number of injuries occur during the maintenance and repair of lead-acid batteries. These injuries include burns from electrical arcing and acid exposure, as well as strained muscles and crushed hands. The National Institute for Occupational Safety and Health investigated the design and implementation of these batteries to identify safety interventions that can mitigate these inherent hazards. This paper promotes practical design modifications, such as reducing the size and weight of battery assembly lids in conjunction with lift assists, as well as using five-pole cable connectors to improve safety.
Ionic liquid as an electrolyte additive for high performance lead-acid batteries

Science.gov (United States)

Deyab, M. A.

2018-06-01

The performance of lead-acid battery is improved in this work by inhibiting the corrosion of negative battery electrode (lead) and hydrogen gas evolution using ionic liquid (1-ethyl-3-methylimidazolium diethyl phosphate). The results display that the addition of ionic liquid to battery electrolyte (5.0 M H2SO4 solution) suppresses the hydrogen gas evolution to very low rate 0.049 ml min-1 cm-2 at 80 ppm. Electrochemical studies show that the adsorption of ionic liquid molecules on the lead electrode surface leads to the increase in the charge transfer resistance and the decrease in the double layer capacitance. I also notice a noteworthy improvement of battery capacity from 45 mAh g-1 to 83 mAh g-1 in the presence of ionic liquid compound. Scanning electron microscopy and energy dispersive X-ray analysis confirm the adsorption of ionic liquid molecules on the battery electrode surface.
Enhanced performance of starter lighting ignition type lead-acid batteries with carbon nanotubes as an additive to the active mass

Science.gov (United States)

Marom, Rotem; Ziv, Baruch; Banerjee, Anjan; Cahana, Beni; Luski, Shalom; Aurbach, Doron

2015-11-01

Addition of various carbon materials into lead-acid battery electrodes was studied and examined in order to enhance the power density, improve cycle life and stability of both negative and positive electrodes in lead acid batteries. High electrical-conductivity, high-aspect ratio, good mechanical properties and chemical stability of multi-wall carbon nanotubes (MWCNT, unmodified and mofified with carboxylic groups) position them as viable additives to enhance the electrodes' electrical conductivity, to mitigate the well-known sulfation failure mechanism and improve the physical integration of the electrodes. In this study, we investigated the incorporation-effect of carbon nanotubes (CNT) to the positive and the negative active materials in lead-acid battery prototypes in a configuration of flooded cells, as well as gelled cells. The cells were tested at 25% and 30% depth-of-discharge (DOD). The positive effect of the carbon nanotubes (CNT) utilization as additives to both positive and negative electrodes of lead-acid batteries was clearly demonstrated and is explained herein based on microscopic studies.
Effects of lead arsenate sprays on the fruit growth and sugar and acid contents in Natsudaidai (Citrus natsudaidai Hayata)

Energy Technology Data Exchange (ETDEWEB)

Kadoya, K; Kuraoka, T; Matsumoto, K

1965-01-01

The juice of the fruit of Citrus natsudaidai is characterized by high acidity. The acidity of the juice was most effectively reduced by treatment with lead arsenate spray at an early fruit growth stage when the acids were being most actively formed. The water-soluble organic acid content of leaves was not affected. The sugar content of the juice was increased by the treatment. The activity of phosphoenolpyruvate carboxylase was lowered in the vesicles of fruit sprayed with lead arsenate. It was also much depressed in the extracts from normal fruit when arsenic trioxide was added. Arsenic was detected in the vesicles of treated fruit. 15 references, 9 figures.
The addition of red lead to flat plate and tubular valve regulated miners cap lamp lead-acid batteries

Energy Technology Data Exchange (ETDEWEB)

Ferg, E.E.; Loyson, P. [Department of Chemistry, Nelson Mandela Metropolitan University, P.O. Box 77000, Port Elizabeth 6031 (South Africa); Poorun, A. [Willard Batteries, P.O. Box 1844, Port Elizabeth 6000 (South Africa)

2006-04-21

The study looked at the use of red lead in the manufacturing of valve regulated lead acid (VRLA) miners cap lamp (MCL) batteries that were made with either flat plate or tubular positive electrodes. A problem with using only grey oxide in the manufacture of thick flat plate or tubular electrodes is the poor conversion of the active material to the desired lead dioxide. The addition of red lead to the initial starting material improves the formation efficiency but is considerably more expensive thereby increasing the cost of manufacturing. The study showed that by carefully controlling the formation conditions in terms of the voltage and temperature of a battery, good capacity performance can be achieved for cells made with flat plate electrodes that contain up to 25% red lead. The small amount of red lead in the active cured material reduces the effect of electrode surface sulphate formation and allows the battery to achieve its rated capacity within the first few cycles. Batteries made with flat plate positive electrodes that contained more that 50% red lead showed good initial capacity but had poor structural active material bonding. The study showed that MCL batteries made with tubular positive electrodes that contained less than 75% red lead resulted in a poorly formed electrode with limited capacity utilization. Pickling and soaking times of the tubular electrodes should be kept at a minimum thereby allowing higher active material utilization during subsequent capacity cycling. The study further showed that it is beneficial to use higher formation rates in order to reduce manufacturing time and to improve the active material characteristics. (author)
The Comparative Performance of Batteries: The Lead-Acid and the Aluminum-Air Cells.

Science.gov (United States)

LeRoux, Xavier; And Others

1996-01-01

Describes a teaching program that shows how electrochemical principles can be conveyed by means of hands-on experiences of student-centered teaching experiments. Employs the readily available lead-acid cell and the simple aluminum-air cell. Discusses the batteries, equilibrium cell potential, performance comparison, current, electrode separation,…
Lipoic acid in combination with a chelator ameliorates lead-induced peroxidative damages in rat kidney

Energy Technology Data Exchange (ETDEWEB)

Sivaprasad, R.; Nagaraj, M.; Varalakshmi, P. [Department of Medical Biochemistry, University of Madras (Taramani), Chennai 600 113 (India)

2002-08-01

The deleterious effect of lead has been attributed to lead-induced oxidative stress with the consequence of lipid peroxidation. The present study was designed to investigate the combined effect of DL-{alpha}-lipoic acid (LA) and meso-2,3-dimercaptosuccinic acid (DMSA) on lead-induced peroxidative damages in rat kidney. The increase in peroxidated lipids in lead-poisoned rats was accompanied by alterations in antioxidant defence systems. Lead acetate (Pb, 0.2%) was administered in drinking water for 5 weeks to induce lead toxicity. LA (25 mg/kg body weight per day i.p) and DMSA (20 mg/kg body weight per day i.p) were administered individually and also in combination during the sixth week. Nephrotoxic damage was evident from decreases in the activities of {gamma}-glutamyl transferase and N-acetyl {beta}-D-glucosaminidase, which were reversed upon combined treatment with LA and DMSA. Rats subjected to lead intoxication showed a decline in the thiol capacity of the cell, accompanied by high malondialdehyde levels along with lowered activities of catalase, superoxide dismutase, glutathione peroxidase and glutathione metabolizing enzymes (glutathione reductase, glucose-6-phosphate dehydrogenase, glutathione-S-transferase). Supplementation with LA as a sole agent showed considerable changes over oxidative stress parameters. The study has highlighted the combined effect of both drugs as being more effective in reversing oxidative damage by bringing about an improvement in the reductive status of the cell. (orig.)
78 FR 58574 - Maintenance, Testing, and Replacement of Vented Lead-Acid Storage Batteries for Nuclear Power Plants

Science.gov (United States)

2013-09-24

...-Acid Storage Batteries for Nuclear Power Plants AGENCY: Nuclear Regulatory Commission. ACTION... for Nuclear Power Plants.'' The guide describes methods that the NRC staff considers acceptable for... replacement of vented lead-acid storage batteries in nuclear power plants. ADDRESSES: Please refer to Docket...
Role of ascorbic acid supplement in amelioration of anaemia in lead intoxication.

Science.gov (United States)

Farooq, Yasir; Farooq, Muhammad Asif; Hussain, Aamir

2016-09-01

To assess anaemia and oxidative stress in rats that were injected lead and to evaluate the possible effects of ascorbic acid supplementation on these parameters. This randomised control trial study was conducted at the Army Medical College, Rawalpindi, Pakistan, from October 2007 to September 2008, and comprised Sprague Dawley rats. The rats were randomly divided into three groups. The rats in Group 1 were given weekly injections of sodium acetate, and rats of Group 2 and 3 were given weekly injections of lead acetate. Ascorbic acid was supplemented in the drinking water of rats of Group 3. At the end of six weeks, terminal sampling was done and blood obtained was used to assess the serum malondialdehyde levels and red cell parameters. Of the 105 rats, each group had 35(33.33%). The overall mean age was 105±15 days and the mean weight was 225±25gm. The mean malondialdehyde level was 3.2±0.39 µmol /L in Group 1, 7.8±0.48 in Group 2 and 3.8±0.34 in Group 3 (plead intoxication.
High folic acid consumption leads to pseudo-MTHFR deficiency, altered lipid metabolism, and liver injury in mice.

OpenAIRE

Christensen, K. E.; Mikael, L. G.; Leung, K. Y.; Lévesque, N.; Deng, L.; Wu, Q.; Malysheva, O. V.; Best, A.; Caudill, M. A.; Greene, N. D.; Rozen, R.

2015-01-01

Increased consumption of folic acid is prevalent, leading to concerns about negative consequences. The effects of folic acid on the liver, the primary organ for folate metabolism, are largely unknown. Methylenetetrahydrofolate reductase (MTHFR) provides methyl donors for S-adenosylmethionine (SAM) synthesis and methylation reactions.
A multifunctional energy-storage system with high-power lead-acid batteries

Science.gov (United States)

Wagner, R.; Schroeder, M.; Stephanblome, T.; Handschin, E.

A multifunctional energy storage system is presented which is used to improve the utilization of renewable energy supplies. This system includes three different functions: (i) uninterruptible power supply (UPS); (ii) improvement of power quality; (iii) peak-load shaving. The UPS application has a long tradition and is used whenever a reliable power supply is needed. Additionally, nowadays, there is a growing demand for high quality power arising from an increase of system perturbation of electric grids. Peak-load shaving means in this case the use of renewable energy stored in a battery for high peak-load periods. For such a multifunctional application large lead-acid batteries with high power and good charge acceptance, as well as good cycle life are needed. OCSM batteries as with positive tubular plates and negative copper grids have been used successfully for a multitude of utility applications. This paper gives two examples where multifunctional energy storage systems have started operation recently in Germany. One system was installed in combination with a 1 MW solar plant in Herne and another one was installed in combination with a 2 MW wind farm in Bocholt. At each place, a 1.2 MW h (1 h-rate) lead-acid battery has been installed. The batteries consist of OCSM cells with the standard design but modified according to the special demand of a multifunctional application.
Using Acid Number as a Leading Indicator of Refrigeration and Air Conditioning System Performance

Energy Technology Data Exchange (ETDEWEB)

Dennis Cartlidge; Hans Schellhase

2003-07-31

This report summarizes a literature review to assess the acidity characteristics of the older mineral oil and newer polyolester (POE) refrigeration systems as well as to evaluate acid measuring techniques used in other non-aqueous systems which may be applicable for refrigeration systems. Failure in the older chlorofluorocarbon/hydrochlorofluorocarbon (CFC/HCFC) / mineral oil systems was primarily due to thermal degradation of the refrigerant which resulted in the formation of hydrochloric and hydrofluoric acids. These are strong mineral acids, which can, over time, severely corrode the system metals and lead to the formation of copper plating on iron surfaces. The oil lubricants used in the older systems were relatively stable and were not prone to hydrolytic degradation due to the low solubility of water in oil. The refrigerants in the newer hydrofluorocarbon (HFC)/POE systems are much more thermally stable than the older CFC/HCFC refrigerants and mineral acid formation is negligible. However, acidity is produced in the new systems by hydrolytic decomposition of the POE lubricants with water to produce the parent organic acids and alcohols used to prepare the POE. The individual acids can therefore vary but they are generally C5 to C9 carboxylic acids. Organic acids are much weaker and far less corrosive to metals than the mineral acids from the older systems but they can, over long time periods, react with metals to form carboxylic metal salts. The salts tend to accumulate in narrow areas such as capillary tubes, particularly if residual hydrocarbon processing chemicals are present in the system, which can lead to plugging. The rate of acid production from POEs varies on a number of factors including chemical structure, moisture levels, temperature, acid concentration and metals. The hydrolysis rate of reaction can be reduced by using driers to reduce the free water concentration and by using scavenging chemicals which react with the system acids. Total acid

Development and testing of a bipolar lead-acid battery for hybrid electric vehicles

NARCIS (Netherlands)

Saakes, M.; Kluiters, E.; Schmal, D.; Mourad, S.; Have, P.T.J.H. ten

1999-01-01

An 80 V bipolar lead-acid battery was constructed and tested using hybrid electric vehicle (HEV) drive cycles. Drive cycles with a peak power of 6.7 kW, equal to 1/5 of the total power profile required for the HEV studied, were run successfully. Model calculations showed that the 80 V module
Lead-acid batteries in micro-hybrid applications. Part I. Selected key parameters

Science.gov (United States)

Schaeck, S.; Stoermer, A. O.; Kaiser, F.; Koehler, L.; Albers, J.; Kabza, H.

Micro-hybrid electric vehicles were launched by BMW in March 2007. These are equipped with brake energy regeneration (BER) and the automatic start and stop function (ASSF) of the internal combustion engine. These functions are based on common 14 V series components and lead-acid (LA) batteries. The novelty is given by the intelligent onboard energy management, which upgrades the conventional electric system to the micro-hybrid power system (MHPS). In part I of this publication the key factors for the operation of LA batteries in the MHPS are discussed. Especially for BER one is high dynamic charge acceptance (DCA) for effective boost charging. Vehicle rest time is identified as a particular negative parameter for DCA. It can be refreshed by regular fully charging at elevated charge voltage. Thus, the batteries have to be outstandingly robust against overcharge and water loss. This can be accomplished for valve-regulated lead-acid (VRLA) batteries at least if they are mounted in the trunk. ASSF goes along with frequent high-rate loads for warm cranking. The internal resistance determines the drop of the power net voltage during cranking and is preferably low for reasons of power net stability even after years of operation. Investigations have to be done with aged 90 Ah VRLA-absorbent glass mat (AGM) batteries. Battery operation at partial state-of-charge gives a higher risk of deep discharging (overdischarging). Subsequent re-charging then is likely to lead to the formation of micro-short circuits in the absorbent glass mat separator.
Speciation of arsenic in biological samples.

Science.gov (United States)

Mandal, Badal Kumar; Ogra, Yasumitsu; Anzai, Kazunori; Suzuki, Kazuo T

2004-08-01

Speciation of arsenicals in biological samples is an essential tool to gain insight into its distribution in tissues and its species-specific toxicity to target organs. Biological samples (urine, hair, fingernail) examined in the present study were collected from 41 people of West Bengal, India, who were drinking arsenic (As)-contaminated water, whereas 25 blood and urine samples were collected from a population who stopped drinking As contaminated water 2 years before the blood collection. Speciation of arsenicals in urine, water-methanol extract of freeze-dried red blood cells (RBCs), trichloroacetic acid treated plasma, and water extract of hair and fingernail was carried out by high-performance liquid chromatography (HPLC)-inductively coupled argon plasma mass spectrometry (ICP MS). Urine contained arsenobetaine (AsB, 1.0%), arsenite (iAs(III), 11.3), arsenate (iAs(V), 10.1), monomethylarsonous acid (MMA(III), 6.6), monomethylarsonic acid (MMA(V), 10.5), dimethylarsinous acid (DMA(III), 13.0), and dimethylarsinic acid (DMA(V), 47.5); fingernail contained iAs(III) (62.4%), iAs(V) (20.2), MMA(V) (5.7), DMA(III) (8.9), and DMA(V) (2.8); hair contained iAs(III) (58.9%), iAs(V) (34.8), MMA(V) (2.9), and DMA(V) (3.4); RBCs contained AsB (22.5%) and DMA(V) (77.5); and blood plasma contained AsB (16.7%), iAs(III) (21.1), MMA(V) (27.1), and DMA(V) (35.1). MMA(III), DMA(III), and iAs(V) were not found in any plasma and RBCs samples, but urine contained all of them. Arsenic in urine, fingernails, and hair are positively correlated with water As, suggesting that any of these measurements could be considered as a biomarker to As exposure. Status of urine and exogenous contamination of hair urgently need speciation of As in these samples, but speciation of As in nail is related to its total As (tAs) concentration. Therefore, total As concentrations of nails could be considered as biomarker to As exposure in the endemic areas.
Research on SOC Calibration of Large Capacity Lead Acid Battery

Science.gov (United States)

Ye, W. Q.; Guo, Y. X.

2018-05-01

Large capacity lead-acid battery is used in track electric locomotive, and State of Charge (SOC) is an important quantitative parameter of locomotive power output and operating mileage of power emergency recovery vehicle. But State of Charge estimation has been a difficult part in the battery management system. In order to reduce the SOC estimation error better, this paper uses the linear relationship of Open Circuit Voltage (OCV) and State of Charge to fit the SOC-OCV curve equation by MATLAB. The method proposed in this paper is small, easy to implement and can be used in the battery non-working state SOC estimation correction, improve the estimation accuracy of SOC.
The importance of glutamate, glycine, and γ-aminobutyric acid transport and regulation in manganese, mercury and lead neurotoxicity

International Nuclear Information System (INIS)

Fitsanakis, Vanessa A.; Aschner, Michael

2005-01-01

Historically, amino acids were studied in the context of their importance in protein synthesis. In the 1950s, the focus of research shifted as amino acids were recognized as putative neurotransmitters. Today, many amino acids are considered important neurochemicals. Although many amino acids play a role in neurotransmission, glutamate (Glu), glycine (Gly), and γ-aminobutyric acid (GABA) are among the more prevalent and better understood. Glu, the major excitatory neurotransmitter, and Gly and GABA, the major inhibitory neurotransmitters, in the central nervous system, are known to be tightly regulated. Prolonged exposure to environmental toxicants, such as manganese (Mn), mercury (Hg), or lead (Pb), however, can lead to dysregulation of these neurochemicals and subsequent neurotoxicity. While the ability of these metals to disrupt the regulation of Glu, Gly and GABA have been studied, few articles have examined the collective role of these amino acids in the respective metal's mechanism of toxicity. For each of the neurotransmitters above, we will provide a brief synopsis of their regulatory function, including the importance of transport and re-uptake in maintaining their optimal function. Additionally, the review will address the hypothesis that aberrant homeostasis of any of these amino acids, or a combination of the three, plays a role in the neurotoxicity of Mn, Hg, or Pb
Minimisation of the LCOE for the hybrid power supply system with the lead-acid battery

Directory of Open Access Journals (Sweden)

Kasprzyk Leszek

2017-01-01

Full Text Available The paper presents the methodology of minimisation of the unit cost of production of energy generated in the hybrid system compatible with the lead-acid battery, and used to power a load with the known daily load curve. For this purpose, the objective function in the form of the LCOE and the genetic algorithm method were used. Simulation tests for three types of load with set daily load characteristics were performed. By taking advantage of the legal regulations applicable in the territory of Poland, regarding the energy storing in the power system, the optimal structure of the prosumer solar-wind system including the lead-acid battery, which meets the condition of maximum rated power, was established. An assumption was made that the whole solar energy supplied to the load would be generated in the optimised system.
A Comparative Study of Lithium Ion to Lead Acid Batteries for use in UPS Applications

DEFF Research Database (Denmark)

Stan, Ana-Irina; Swierczynski, Maciej Jozef; Stroe, Daniel Ioan

2014-01-01

Uninterruptible power supply (UPS) systems have incorporated in their structure an electrochemical battery which allows for smooth power supply when a power failure occurs. In general, UPS systems are based on lead acid batteries; mainly a valve regulated lead acid (VRLA) battery. Recently, lithium...... ion batteries are getting more and more attention for their use in the back-up power systems and UPSs, because of their superior characteristics, which include increased safety and higher gravimetric and volumetric energy densities. This fact allows them to be smaller in size and weight less than VRLA...... batteries, which are currently used in UPS applications. The main purpose of this paper is to analyze how Li-ion batteries can become a useful alternative to present VRLA. In this study, three different electrochemical battery technologies were investigated; two of the most appealing Li-ion chemistries...
Analysis of lead/acid battery life cycle factors: their impact on society and the lead industry

Science.gov (United States)

Robertson, J. G. S.; Wood, J. R.; Ralph, B.; Fenn, R.

The underlying theme of this paper is that society, globally, is undergoing a fundamental conceptual shift in the way it views the environment and the role of industry within it. There are views in certain quarters that this could result in the virtual elimination of the lead industry's entire product range. Despite these threats, it is argued that the prospects for the lead industry appear to be relatively favourable in a number of respects. The industry's future depends to a significant degree, however, upon its ability to argue its case in a number of key areas. It is contended, therefore, that if appropriate strategies and means are promulgated, the prospects of the industry would appear to be relatively healthy. But, for this to happen with optimal effectiveness, a conceptual change will be necessary within the industry. New strategies and tools will have to be developed. These will require a significantly more integrated, holistically based and 'reflexive' approach than previously. The main elements of such an approach are outlined. With reference to the authors' ongoing research into automotive lead/acid starting lighting ignition (SLI) batteries, the paper shows how the technique of in-depth life cycle assessment (LCA), appropriately adapted to the needs of the industry, will provide a crucial role in this new approach. It also shows how it may be used as an internal design and assessment tool to identify those stages in the battery life cycle that give rise to the greatest environmental burdens, and to assess the effects of changes in the cycle to those burdens. It is argued that the development of this approach requires the serious and urgent attention of the whole of the lead industry. Also to make the LCA tool fully effective, it must be based on a 'live' database that is produced, maintained and continually updated by the industry.
A review of physical properties of separators for valve-regulated lead/acid batteries

Energy Technology Data Exchange (ETDEWEB)

Zguris, G.C. [Hovosorb Separators, Hollingsworth and Vose Co., West Groton, MA (United States)

1996-03-01

The microglass separator has been used from the conception of valve-regulated lead/acid (VRLA) technology. There is increasing recognition that the separator has a critical role in battery performance. Research is supporting the position that compression exerted by the separator has an important role in premature capacity loss. Some companies have suggested that the separator compression set/creep plays a critical role in the battery failure mechanism in float applications. ALABC studies have shown that designs with higher compression improve the cycle life of batteries. Increasing numbers of manufacturers are designing their separators around the end-application of the battery. The separator in a VRLA battery is not an inactive spacer/barrier, as in a flooded lead/acid cell. Instead, these separators function as a key element, the third electrode. This paper reviews aspects of the microglass separator used in VRLA batteries. Information is provided to make a better separator selection, since a 100% microglass media, or any recombinant battery separator mat (RBSM) for a VRLA battery has a critical role in assuring the performance of the battery. A poor design can thus decrease the expected life of the battery. (orig.)
THIOGLYCOLIC ACID ESTERIFIED IN TO RICE STRAW FOR REMOVING LEAD FROM AQUEOUS SOLUTION

Directory of Open Access Journals (Sweden)

R. Gong

2011-09-01

Full Text Available Thiol rice straw (TRS was prepared by esterifying thioglycolic acid onto rice straw in the medium of acetic anhydride and acetic acid with sulfuric acid as catalyst. The sorption of lead (Pb on TRS from aqueous solution was subsequently investigated. The batch experiments showed that Pb removal was dependent on initial pH, sorbent dose, Pb concentration, contact time, and temperature. The maximum value of Pb removal appeared at pH 5. For 100 mg/L of Pb solution, a removal ratio of greater than 98% could be achieved with 2.0 g/L or more of TRS. The isothermal data of Pb sorption conformed well to the Langmuir model, and the maximum sorption capacity (Qm of TRS for Pb was 104.17 mg/g. The equilibrium of Pb removal was reached within 120 min. The Pb removal process could be described by the pseudo-first-order kinetic model. The thermodynamic study indicated that the Pb removal process was spontaneous and endothermic.
Method of handling of scrap lead from lead-acid batteries

Energy Technology Data Exchange (ETDEWEB)

Sytschev, A P; Kim, G V; Larin, V F; Sidorova, G D; Vicharev, I G; Kuur, V P; Achmetov, R S; Moiseev, G L; Maslov, V I; Kabatschek, V G

1979-12-13

Scrap lead and the casings of accumulators are mined and molten together in oxidixing atmosphere at a temperature of 1300 to 1500/sup 0/C. The lead oxide contained in the melt is then reduced to blue lead. Due to the combustion of the accumulator casings consisting of organic substances the fuel consumption in the melting process is reduced in accordance. The oxidizing atmosphere in the melting process is produced by use of air or oxygen.
Improving lead adsorption through chemical modification of wheat straw by lactic acid

Science.gov (United States)

Mu, Ruimin; Wang, Minxiang; Bu, Qingwei; Liu, Dong; Zhao, Yanli

2018-01-01

This work describes the creation of a new cellulosic material derived from wheat straw modified by lactic acid for adsorption of lead in aqueous solution, called 0.3LANS (the concentration of the lactic acid were 0.3mol/L). Batch experiments were conducted to study the effects of initial pH value, contact time, adsorbent dose, initial concentration and temperature. Fourier transform infrared (FTIR), Elemental analysis, BET surface area and Scanning electron micrographs (SEM) analysis were used to investigate the chemical modification. Adsorption isotherm models namely, Langmuir, Freundlich were used to analyse the equilibrium data, and the Langmuir isotherm model provided the best correlation, means that the adsorption was chemical monolayer adsorption and the adsorption capacity qm was increased with increasing temperature, and reached 51.49mg/g for 0.3LANS at 35°C, showing adsorption was exothermic.
The Environmental Burdens of Lead-Acid Batteries in China: Insights from an Integrated Material Flow Analysis and Life Cycle Assessment of Lead

Directory of Open Access Journals (Sweden)

Sha Chen

2017-11-01

Full Text Available Lead-acid batteries (LABs, a widely used energy storage equipment in cars and electric vehicles, are becoming serious problems due to their high environmental impact. In this study, an integrated method, combining material flow analysis with life cycle assessment, was developed to analyze the environmental emissions and burdens of lead in LABs. The environmental burdens from other materials in LABs were not included. The results indicated that the amount of primary lead used in LABs accounted for 77% of the total lead production in 2014 in China. The amount of discharged lead into the environment was 8.54 × 105 tonnes, which was mainly from raw material extraction (57.2%. The largest environmental burden was from the raw materials extraction and processing, which accounted for 81.7% of the total environmental burdens. The environmental burdens of the environmental toxicity potential, human toxicity potential-cancer, human toxicity potential-non-cancer, water footprint and land use accounted for more than 90% at this stage. Moreover, the environmental burdens from primary lead was much more serious than regenerated lead. On the basis of the results, main practical measures and policies were proposed to reduce the lead emissions and environmental burdens of LABs in China, namely establishing an effective LABs recycling system, enlarging the market share of the legal regenerated lead, regulating the production of regenerated lead, and avoiding the long-distance transportation of the waste LABs.
Using Diagnostic Assessment to Help Teachers Understand the Chemistry of the Lead-Acid Battery

Science.gov (United States)

Cheung, Derek

2011-01-01

Nineteen pre-service and in-service teachers taking a chemistry teaching methods course at a university in Hong Kong were asked to take a diagnostic assessment. It consisted of seven multiple-choice questions about the chemistry of the lead-acid battery. Analysis of the teachers' responses to the questions indicated that they had difficulty in…
Modeling the effect of succimer (DMSA; dimercaptosuccinic acid) chelation therapy in patients poisoned by lead.

Science.gov (United States)

van Eijkeren, Jan C H; Olie, J Daniël N; Bradberry, Sally M; Vale, J Allister; de Vries, Irma; Clewell, Harvey J; Meulenbelt, Jan; Hunault, Claudine C

2017-02-01

Kinetic models could assist clinicians potentially in managing cases of lead poisoning. Several models exist that can simulate lead kinetics but none of them can predict the effect of chelation in lead poisoning. Our aim was to devise a model to predict the effect of succimer (dimercaptosuccinic acid; DMSA) chelation therapy on blood lead concentrations. We integrated a two-compartment kinetic succimer model into an existing PBPK lead model and produced a Chelation Lead Therapy (CLT) model. The accuracy of the model's predictions was assessed by simulating clinical observations in patients poisoned by lead and treated with succimer. The CLT model calculates blood lead concentrations as the sum of the background exposure and the acute or chronic lead poisoning. The latter was due either to ingestion of traditional remedies or occupational exposure to lead-polluted ambient air. The exposure duration was known. The blood lead concentrations predicted by the CLT model were compared to the measured blood lead concentrations. Pre-chelation blood lead concentrations ranged between 99 and 150 μg/dL. The model was able to simulate accurately the blood lead concentrations during and after succimer treatment. The pattern of urine lead excretion was successfully predicted in some patients, while poorly predicted in others. Our model is able to predict blood lead concentrations after succimer therapy, at least, in situations where the duration of lead exposure is known.
Colloidal 3-Mercaptopropionic Acid Capped Lead Sulfide Quantum Dots in a Low Boiling Point Solvent.

Science.gov (United States)

Reinhart, Chase C; Johansson, Erik

2017-04-26

Colloidal 3-mercaptopropionic acid (3-MPA) capped lead sulfide quantum dots were prepared in a variety of organic solvents stabilized with a quaternary ammonium halide salt. The stabilized colloids' optical properties were studied through optical absorption and emission spectroscopy and found to be dependent on both the concentration of a new ligand and stabilizer, and sample age. Nanocrystal ligand chemistry was studied through a combination of 1 H NMR and two-dimensional Nuclear Overhauser Effect Spectroscopy (NOESY) which revealed full displacement of the original oleate ligand to form a dynamically exchanging ligand shell. The colloids were studied optically and via NMR as they aged and revealed a quantitative conversion of monomeric 3-mercaptopropionic acid to its dimer, dithiodipropionic acid (dTdPA).
Polarization behavior of new and used lead alloys in acid sulfate solutions

Energy Technology Data Exchange (ETDEWEB)

Yu, P.; O' Keefe, T.J. [Univ. of Missouri-Rolla, Materials Research Center and Dept. of Metallurgical Engineering, Rolla, Missouri (United States)

2001-07-01

Polarization and Electrochemical impedance were used to study various lead alloys commercially used to electrowin zinc and copper from acidic sulfate solutions. Anode specimens that had been in service at several electrowinning operations were tested and their electrochemical performance was compared to that obtained from new anode samples. Tests were conducted in sulfuric acid. Cyclic voltammetry was used in a potential range in which both Pb{sup +2} and Pb{sup +4} formed stable phases. Selected polarization tests were also made to study a number of variables, including changes in the concentration of cobalt and manganese in the electrolyte. Results showed that the phases formed on the surface of the anode were critical in defining the electrochemical behavior of the anodes. In particular, certain active phases, which were depolarizing were identified on some of the used anodes. It was possible to duplicate some of these phases in the laboratory. (author)
A NOVEL GEL ELECTROLYTE FOR VALVE-REGULATED LEAD ACID BATTERY

Directory of Open Access Journals (Sweden)

Metin GENÇTEN

2017-03-01

Full Text Available A novel gel electrolyte system used in lead-acid batteries was investigated in this work. The gel systems were prepared by addition different amount of Al2O3, TiO2 and B2O3 into the gelled system consisting of 6 wt% fumed silica and 30 wt% sulfuric acid solution. The anodic peak currents and peak redox capacities of the gel electrolytes were characterized by cyclic voltammetric method. They decreased by the time B2O3 and Al2O3 were used as additives in fumed silica based gel electrolyte system. However, these values increased by the adding 3.0 wt% of TiO2. The solution and charge transfer resistances of the gel electrolytes were investigated by electrochemical impedance spectroscopy. While the solution resistances were lower in gel systems having different amount additives than pure fumed silica based gel, the charge transfer resistance was the lowest in gel electrolytes consisting fumed silica and fumed silica-TiO2. The battery performances were studied by obtaining discharge curves of prepared gel electrolytes. The performance of gelled systems were higher than that of non-gelled electrolyte at room temperature. The mixture of fumed silica-TiO2 was suggested an alternative gel formulation for gel VRLA batteries.
Inducible arginase 1 deficiency in mice leads to hyperargininemia and altered amino acid metabolism.

Directory of Open Access Journals (Sweden)

Yuan Yan Sin

Full Text Available Arginase deficiency is a rare autosomal recessive disorder resulting from a loss of the liver arginase isoform, arginase 1 (ARG1, which is the final step in the urea cycle for detoxifying ammonia. ARG1 deficiency leads to hyperargininemia, characterized by progressive neurological impairment, persistent growth retardation and infrequent episodes of hyperammonemia. Using the Cre/loxP-directed conditional gene knockout system, we generated an inducible Arg1-deficient mouse model by crossing "floxed" Arg1 mice with CreER(T2 mice. The resulting mice (Arg-Cre die about two weeks after tamoxifen administration regardless of the starting age of inducing the knockout. These treated mice were nearly devoid of Arg1 mRNA, protein and liver arginase activity, and exhibited symptoms of hyperammonemia. Plasma amino acid analysis revealed pronounced hyperargininemia and significant alterations in amino acid and guanidino compound metabolism, including increased citrulline and guanidinoacetic acid. Despite no alteration in ornithine levels, concentrations of other amino acids such as proline and the branched-chain amino acids were reduced. In summary, we have generated and characterized an inducible Arg1-deficient mouse model exhibiting several pathologic manifestations of hyperargininemia. This model should prove useful for exploring potential treatment options of ARG1 deficiency.
Differential pulse polarography of cadmium-and lead-urate and adsorptive stripping voltammetric determination of uric acid.

Science.gov (United States)

Gandour, M A; Ensaf-Aboul-Kasim; Amrallah, A H; Farghaly, O A

1994-03-01

The complex formation between uric acid and zinc, cadmium and lead ions has been investigated using differential pulse polarography in 0.01M NaNO(3). It is found that the complexes formed by Cd(II) and Pb(II) ions with uric acid have the stoichiometry of 1:2 and the logarithmic values of the apparent stability constant are 9.47 and 11.7, respectively. On the other hand, zinc(II) ions do not give any indication of complexation with uric acid. A sensitive voltammetric method is developed for the quantitative determination of uric acid. This method is based on controlled adsorptive preconcentration of uric acid on the hanging mercury drop electrode (HMDE), followed by tracing the voltammogram in the cathodic going potential scan. The modes used are direct current stripping voltammetry (DCSV) and differential pulse stripping voltammetry (DPSV). The detection limits found were 8 x 10(-9)M (quiescent period 15 sec) by DPSV and 1.6 x 10(-8)M by DCSV.

Bio-toxicological supervision op workers exposed to lead poisoning hazard. Systematic examination of amino acids, in urine and plasma

International Nuclear Information System (INIS)

Harduin, Jean-Claude

1971-01-01

A bio-toxicological chart was established for the workers in a firm handling lead. The known facts concerning professional lead poisoning are outlined, after which the importance of lead work in a nuclear center is discussed. The work station of each man is described and the results of analyses made during atmospheric checks on the site are given with sampling techniques. Since the biological chart is centered on the chromatographic exploration of amino acids in blood and urine, the analytical technique used is described and the different technical modifications made to the standard technique reported. The results obtained on reference subjects are compared with those found in the specialized literature. The results found in lead workers are then presented in the form of histograms, which better illustrate the differences observed with respect to the reference subjects. An hematological and toxicological balance-sheet is drawn up and the correlation existing between the results of coproporphyrine, lead and delta-aminolevulinic acid analyses in urine is checked. Biological detection of lead-poisoning has the advantage of providing an early diagnosis, thus enabling the works doctor to forestall the effects of this professional disease before any clinical symptoms appear. (author) [fr
Features of the low-power charge controller of lead-acid current sources charged by solar batteries

International Nuclear Information System (INIS)

Tukfatullin, O.F.; Yuldoshev, I.A.; Solieva, N.A.

2008-01-01

Influence of different factors on exploitations characteristics of solar photoelectric plant is investigated by field-performance data. A construction of charge controller of the lead-acid accumulator battery charging by means of solar battery is analyzed taking into account these factors. (authors)
Co-remediation of the lead-polluted garden soil by exogenous natural zeolite and humic acids.

Science.gov (United States)

Shi, Wei-yu; Shao, Hong-bo; Li, Hua; Shao, Ming-an; Du, Sheng

2009-08-15

The current study reported the co-remediation effect on the lead-polluted garden soil by zeolite and humic acids (HA), which was from comparing with the remediation of single zeolite in term of the lead fraction of sequential extraction in the soil and the distribution of lead in different parts of rape. Mixed treatment (zeolite and HA) and single treatment (zeolite) were, respectively, applied to the artificially polluted garden soil to examine the difference of their remediation effects in pot experiment. Results indicated that the co-remediation led to significantly greater (plead concentration in plants than by singly adding to zeolite. The co-application of zeolite and HA reduced the available fraction of lead compounds, but slightly increased (plead compounds in the garden soil, compared with the application of single zeolite, especially in the severe lead-polluted soil (> or =1000 mg kg(-1)). This method might be an efficient way to remediate the lead-polluted soils on a large scale, although zeolite is a kind of hazardous material.
Protective effects of lipoic acid against oxidative stress induced by lead acetate and gamma-irradiation in the kidney and lung in albino rats

International Nuclear Information System (INIS)

Rezk, R.G.; Abdel-Rahman, N.A.

2013-01-01

Lipoic acid is widely used as antioxidant that protects tissues against a range of oxidative stress. The present study was designed to determine the protective effect of lipoic acid against oxidative organ damage induced by lead intoxication and/or gamma-irradiation. Rats were treated daily intrapritonealy (i. p.) with lipoic acid( 200 mg/kg/b.w.) for 15 consecutive days before lead acetate injection(30 mg/kg/b.w) i.p. for 5 days and/ or whole body. gamma-irradiation (3 Gy). Animals were sacrificed on the 3rd day post the last treatment. Histological examination of kidney and lung tissues through light microscope showed that lead acetate injection and/or exposure to gamma radiation has provoked severe architectural damage in both tissues as necrotic lesions, atrophoid glomerulei and degenerated proximal and distal convoluted tubules, severe bronchiole fibrosis, decreased ciliated bronchioles and dilated and widened pulmonary artery. Histological damage was associated with significant biochemical. changes as increase in lead, copper, iron, zinc and calcium levels in both kidney and lung tissues. Kidney and lung of rats treated with lipoic acid before lead intoxication and/or gamma-irradiation showed significant regenerated glomerulei structure, well-defined structure of proximal and distal convoluted tubules, regenerated ciliated bronchiole structure and improved pulmonary artery. Tissue regeneration was associated with significant decrease in Pb, Cu, Fe, Zn, and Ca levels in kidney and lung and prevented the accumulation of metals in these organs. It could be concluded that lipoic acid administration before lead and/or whole body gamma-irradiation might be capable to attenuate lead and/or gamma radiation induced organ injury and organ metals disruption
Remediation of lead contaminated soil

International Nuclear Information System (INIS)

Urban, W.; Krishnamurthy, S.

1992-01-01

Lead contaminated soil in urban area is of major concern because of the potential health risk to children. Many studies have established a direct correlation between lead in soil and elevated blood lead levels in children. In Minneapolis, Minnesota, Mielke et al. (1983) reported that 50% of the Hmong children with lead poisioning were in areas where soil lead levels were between 500 and 1000 micrograms per gram (ug/g), and 40% of the children suffering from lead poisioning lived in areas where soil lead levels exceeded 1000 ug/g. In urban areas, lead pollution in soil has come from many different sources. The sources include lead paint, lead batteries and automobile exhaust. Olson and Skogerbee (1975) found the following lead compounds in soils where the primary source of pollution was from automobiles: lead sulfate, lead oxide, lead dioxide, lead sulfide, and metallic lead. The primary form of lead found was lead sulfate. Lead sulfate, lead tetraoxide, white lead, and other forms of lead have been used in the manufacture of paints for houses. At present, two remediation techniques, solidification and Bureau of Mines fluosilicic acid leaching, are available for lead-contaminated sites. The objective of the present investigation at the Risk Reduction Engineering Laboratory (RREL), Edison, was to try to solubilize the lead species by appropriate reagents and then recover the contaminants by precipitation as lead sulfate, using environmentally acceptable methods. The apparatus used for mixing was a LabMaster mixer, with variable speed and high-shear impeller. Previous work had used nitric acid for dissolving metallic lead. Owing to the environmental concerns, it was decided to use acetic acid in the presence of oxygen. The theoretical justification for this approach is the favorable redox potential for the reaction between metallic lead, acetic acid, and gaseous oxygen
Dietary stearic acid leads to a reduction of visceral adipose tissue in athymic nude mice.

Directory of Open Access Journals (Sweden)

Ming-Che Shen

Full Text Available Stearic acid (C18:0 is a long chain dietary saturated fatty acid that has been shown to reduce metastatic tumor burden. Based on preliminary observations and the growing evidence that visceral fat is related to metastasis and decreased survival, we hypothesized that dietary stearic acid may reduce visceral fat. Athymic nude mice, which are used in models of human breast cancer metastasis, were fed a stearic acid, linoleic acid (safflower oil, or oleic acid (corn oil enriched diet or a low fat diet ad libitum. Total body weight did not differ significantly between dietary groups over the course of the experiment. However visceral fat was reduced by ∼70% in the stearic acid fed group compared to other diets. In contrast total body fat was only slightly reduced in the stearic acid diet fed mice when measured by dual-energy x-ray absorptiometry and quantitative magnetic resonance. Lean body mass was increased in the stearic acid fed group compared to all other groups by dual-energy x-ray absorptiometry. Dietary stearic acid significantly reduced serum glucose compared to all other diets and increased monocyte chemotactic protein-1 (MCP-1 compared to the low fat control. The low fat control diet had increased serum leptin compared to all other diets. To investigate possible mechanisms whereby stearic acid reduced visceral fat we used 3T3L1 fibroblasts/preadipocytes. Stearic acid had no direct effects on the process of differentiation or on the viability of mature adipocytes. However, unlike oleic acid and linoleic acid, stearic acid caused increased apoptosis (programmed cell death and cytotoxicity in preadipocytes. The apoptosis was, at least in part, due to increased caspase-3 activity and was associated with decreased cellular inhibitor of apoptosis protein-2 (cIAP2 and increased Bax gene expression. In conclusion, dietary stearic acid leads to dramatically reduced visceral fat likely by causing the apoptosis of preadipocytes.
Quality Control of Lead-Acid Battery according to Its Condition Test for UPS Supplier and Manufacturers

Directory of Open Access Journals (Sweden)

Tsung-Chih Hsiao

2014-01-01

Full Text Available The risk of insufficient petroleum resources has forced human beings to emphasize the acquisition and storage of energy. To avoid such situation, this study tends to explore the effective management of lead-acid batteries for effective utilization conforming to the industrial requirements.
An in situ generated carbon as integrated conductive additive for hierarchical negative plate of lead-acid battery

Science.gov (United States)

Saravanan, M.; Ganesan, M.; Ambalavanan, S.

2014-04-01

In this work, we report an in situ generated carbon from sugar as additive in the Negative Active Mass (NAM) which enhances the charge-discharge characteristics of the lead-acid cells. In situ formed sugar derived carbon (SDC) with leady oxide (LO) provides a conductive network and excellent protection against NAM irreversible lead sulfation. The effect of SDC and carbon black (CB) added negative plates are characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), galvanostatic charge-discharge, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), respectively. The results show that subtle changes in the addition of carbon to NAM led to subsequent changes on the performance during partial-state-of-charge (PSoC) operations in lead-acid cells. Furthermore, SDC added cells exhibit remarkable improvement in the rate capability, active material utilization, cycle performance and charge acceptance compared to that of the conventional CB added cells. The impact of SDC with LO at various synthesis conditions on the electrochemical performance of the negative plate is studied systematically.
A green lead hydrometallurgical process based on a hydrogen-lead oxide fuel cell.

Science.gov (United States)

Pan, Junqing; Sun, Yanzhi; Li, Wei; Knight, James; Manthiram, Arumugam

2013-01-01

The automobile industry consumed 9 million metric tons of lead in 2012 for lead-acid batteries. Recycling lead from spent lead-acid batteries is not only related to the sustainable development of the lead industry, but also to the reduction of lead pollution in the environment. The existing lead pyrometallurgical processes have two main issues, toxic lead emission into the environment and high energy consumption; the developing hydrometallurgical processes have the disadvantages of high electricity consumption, use of toxic chemicals and severe corrosion of metallic components. Here we demonstrate a new green hydrometallurgical process to recover lead based on a hydrogen-lead oxide fuel cell. High-purity lead, along with electricity, is produced with only water as the by-product. It has a >99.5% lead yield, which is higher than that of the existing pyrometallurgical processes (95-97%). This greatly reduces lead pollution to the environment.
Quercetin, ascorbic acid, caffeine and ellagic acid are more efficient than rosiglitazone, metformin and glimepiride in interfering with pathways leading to the development of neurological complications associated with diabetes: A comparative in-vitro study

Directory of Open Access Journals (Sweden)

Vineet Mehta

2017-06-01

Full Text Available Neuropathy is the least understood and most devastating complication associated with diabetes. Diabetic neuropathy develops in patients despite of regular therapy, indicating that marketed drugs has minimal effect on pathways leading to the development and progression of these complications. Present study was aimed to evaluate natural compounds for their ability to interfere with pathways leading to the development of diabetes mediated neurological complications and compare their efficacy with marketed anti-diabetic drugs. Anti-diabetic potential of ascorbic acid, gallic acid, quercetin, ellagic acid, cinnamic acid, caffeine and piperine was predicted by evaluating in-silico interaction energy (kcal/mol of these compounds with insulin receptor, peroxisome proliferator-activated receptor gamma-γ and dipeptidyl peptidase-4 proteins. Ascorbic acid, gallic acid, quercetin and ellagic acid showed excellent in-vitro antioxidant activity in DPPH radical scavenging and inhibition of lipid peroxidation assay, which was 1.5–3 folds better than the marketed drugs. Quercetin, gallic acid, cinnamic acid, piperine and caffeine efficiently prevented H2O2 induced genotoxicity, which commercial drugs failed to prevent. Further, quercetin, ellagic acid, caffeine and ascorbic acid were 3–4.7 folds better than marketed drugs in inhibiting α-amylase activity. Herbal molecules and rosiglitazone showed comparable results for glucose uptake, which may be attributed to enhanced GLUT4 translocation into primary neuronal culture under hyperglycemic conditions. In conclusion, currently available marketed anti-diabetic drugs have minimal effect on the pathways leading to diabetic neuropathy and supplementing diabetic therapeutics with quercetin, ascorbic acid, caffeine and ellagic acid may be better suited to counter diabetic neuropathy through inhibiting oxidative stress, genotoxicity and improving neuronal glucose utilization.
Influence of 2,3-dimercaptosuccinic acid on gastrointestinal lead absorption and whole-body lead retention

International Nuclear Information System (INIS)

Kapoor, S.C.; Wielopolski, L.; Graziano, J.H.; LoIacono, N.J.

1989-01-01

2,3-Dimercaptosuccinic acid (DMSA) is a new orally active heavy metal chelator for the treatment of childhood Pb intoxication on an outpatient basis. The influence of DMSA, as well as other chelating agents, on gastrointestinal 203Pb absorption and whole-body 203 Pb retention was examined. Groups of Sprague-Dawley rats (230-260 g) were gavaged with a solution containing approximately 25 mg/kg Pb [as Pb(NO 3 )2] plus 15 microCi 203 Pb. Some groups were then immediately given 0.11 mmol/kg of either DMSA, CaNa2EDTA, D-penicillamine, or BAL by oral gavage, while other groups received the same drugs by ip injection. Control groups received solutions of the drug vehicles po or ip. Whole-body Pb retention and gastrointestinal Pb absorption (whole body retention + urinary Pb excretion) were significantly decreased in rats that received DMSA po. This finding implies that the use of DMSA to treat childhood lead intoxication on an outpatient basis is not associated with a risk for increased Pb absorption
Positive synergistic effect of the reuse and the treatment of hazardous waste on pyrometallurgical process of lead recovery from waste lead-acid batteries

Directory of Open Access Journals (Sweden)

Marija Štulović

2014-09-01

Full Text Available Modification and optimization of the pyrometallurgical process of lead recovering from the waste lead-acid batteries have been studied in this paper. The aim of this research is to develop a cleaner production in the field of the secondary lead metallurgy. Lead smelting process with the addition of flux (sodium(I-carbonate and reducing agents (coke, iron has been followed. The modified smelting process with the addition of hazardous waste (activated carbon as alternative reducing agents has shown positive results on the quality of the secondary lead, the generated slag and the process gases. Filtration efficiency of the gases, the return of baghouse dust to the process and use of oxygen burners have positive effect on the environment protection and energy efficiency. Optimization of the recycling process has been based on the properties of the slag. Stabilization of slag is proposed in the furnace with addition of waste dust from the recycling of cathode ray tube (CRT monitors. Phosphorus compounds from dust reduce leachability of toxic elements from the generated slag. Reduction the slag amount and its hazardous character through the elimination of migratory heavy metals and valorization of useful components have been proposed in the patented innovative device - cylindrical rotating washer/separator.
High folic acid consumption leads to pseudo-MTHFR deficiency, altered lipid metabolism, and liver injury in mice.

Science.gov (United States)

Christensen, Karen E; Mikael, Leonie G; Leung, Kit-Yi; Lévesque, Nancy; Deng, Liyuan; Wu, Qing; Malysheva, Olga V; Best, Ana; Caudill, Marie A; Greene, Nicholas D E; Rozen, Rima

2015-03-01

Increased consumption of folic acid is prevalent, leading to concerns about negative consequences. The effects of folic acid on the liver, the primary organ for folate metabolism, are largely unknown. Methylenetetrahydrofolate reductase (MTHFR) provides methyl donors for S-adenosylmethionine (SAM) synthesis and methylation reactions. Our goal was to investigate the impact of high folic acid intake on liver disease and methyl metabolism. Folic acid-supplemented diet (FASD, 10-fold higher than recommended) and control diet were fed to male Mthfr(+/+) and Mthfr(+/-) mice for 6 mo to assess gene-nutrient interactions. Liver pathology, folate and choline metabolites, and gene expression in folate and lipid pathways were examined. Liver and spleen weights were higher and hematologic profiles were altered in FASD-fed mice. Liver histology revealed unusually large, degenerating cells in FASD Mthfr(+/-) mice, consistent with nonalcoholic fatty liver disease. High folic acid inhibited MTHFR activity in vitro, and MTHFR protein was reduced in FASD-fed mice. 5-Methyltetrahydrofolate, SAM, and SAM/S-adenosylhomocysteine ratios were lower in FASD and Mthfr(+/-) livers. Choline metabolites, including phosphatidylcholine, were reduced due to genotype and/or diet in an attempt to restore methylation capacity through choline/betaine-dependent SAM synthesis. Expression changes in genes of one-carbon and lipid metabolism were particularly significant in FASD Mthfr(+/-) mice. The latter changes, which included higher nuclear sterol regulatory element-binding protein 1, higher Srepb2 messenger RNA (mRNA), lower farnesoid X receptor (Nr1h4) mRNA, and lower Cyp7a1 mRNA, would lead to greater lipogenesis and reduced cholesterol catabolism into bile. We suggest that high folic acid consumption reduces MTHFR protein and activity levels, creating a pseudo-MTHFR deficiency. This deficiency results in hepatocyte degeneration, suggesting a 2-hit mechanism whereby mutant hepatocytes cannot
Study on residual discharge time of lead-acid battery based on fitting method

Science.gov (United States)

Liu, Bing; Yu, Wangwang; Jin, Yueqiang; Wang, Shuying

2017-05-01

This paper use the method of fitting to discuss the data of C problem of mathematical modeling in 2016, the residual discharge time model of lead-acid battery with 20A,30A,…,100A constant current discharge is obtained, and the discharge time model of discharge under arbitrary constant current is presented. The mean relative error of the model is calculated to be about 3%, which shows that the model has high accuracy. This model can provide a basis for optimizing the adaptation of power system to the electrical motor vehicle.
Energy-saving management modelling and optimization for lead-acid battery formation process

Science.gov (United States)

Wang, T.; Chen, Z.; Xu, J. Y.; Wang, F. Y.; Liu, H. M.

2017-11-01

In this context, a typical lead-acid battery producing process is introduced. Based on the formation process, an efficiency management method is proposed. An optimization model with the objective to minimize the formation electricity cost in a single period is established. This optimization model considers several related constraints, together with two influencing factors including the transformation efficiency of IGBT charge-and-discharge machine and the time-of-use price. An example simulation is shown using PSO algorithm to solve this mathematic model, and the proposed optimization strategy is proved to be effective and learnable for energy-saving and efficiency optimization in battery producing industries.
Inhibition treatment of the corrosion of lead artefacts in atmospheric conditions and by acetic acid vapour: use of sodium decanoate

International Nuclear Information System (INIS)

Rocca, E.; Rapin, C.; Mirambet, F.

2004-01-01

The efficiency of linear sodium decanoate, CH 3 (CH 2 ) 8 COONa (noted NaC 10 ), as corrosion inhibitor of lead was determined by electrochemical techniques in two corrosive mediums: ASTM D1384 standard water and acetic acid-enriched solutions. Best results were obtained with 0.05 mol l -1 of NaC 10 solution. In these conditions, the inhibition efficiency can be estimated of 99.9%. The corrosion inhibition effect was confirmed by cyclic atmospheric tests in a climatic chamber in two different conditions: water saturated vapour, and acid acetic enriched vapour simulating the atmosphere in the wooden displays in museums. Surface analyses by SEM and X-ray diffraction indicate that the metal protection is due to the formation of a protective layer mainly composed of lead decanoate Pb(C 10 ) 2 (metallic soap). This inhibition treatment was applied on objects of metallic cultural heritage: gallo-roman sarcophagus in lead. Electrochemical methods confirm the efficiency of treatment on archaeological materials. In conclusion, this inhibitor treatment seems to be very promising against the atmospheric corrosion and the corrosion by organic acid vapour in museums
Acid production potentials of massive sulfide minerals and lead-zinc mine tailings: a medium-term study.

Science.gov (United States)

Çelebi, Emin Ender; Öncel, Mehmet Salim; Kobya, Mehmet

2018-01-01

Weathering of sulfide minerals is a principal source of acid generation. To determine acid-forming potentials of sulfide-bearing materials, two basic approaches named static and kinetic tests are available. Static tests are short-term, and easily undertaken within a few days and in a laboratory. In contrast, kinetic tests are long-term procedures and mostly carried out on site. In this study, experiments were conducted over a medium-term period of 2 months, not as short as static tests and also not as long as kinetic tests. As a result, pH and electrical conductivity oscillations as a function of time, acid-forming potentials and elemental contents of synthetically prepared rainwater leachates of massive sulfides and sulfide-bearing lead-zinc tailings from abandoned and currently used deposition areas have been determined. Although the lowest final pH of 2.70 was obtained in massive pyrite leachate, massive chalcopyrite leachate showed the highest titrable acidity of 1.764 g H 2 SO 4 /L. On the other hand, a composite of currently deposited mine tailings showed no acidic characteristic with a final pH of 7.77. The composite abandoned mine tailing leachate had a final pH of 6.70, close to the final pH of massive galena and sphalerite leachates, and produced a slight titrable acidity of 0.130 g H 2 SO 4 /L.
SureCure{sup (R)}-A new material to reduces curing time and improve curing reproducibility of lead-acid batteries

Energy Technology Data Exchange (ETDEWEB)

Boden, David P.; Loosemore, Daniel V.; Botts, G. Dean [Hammond Lead Products Division, Hammond Group Inc., 2323 165th Street, Hammond, IN 46320 (United States)

2006-08-25

This paper introduces a technology that considerably reduces the time to cure the positive plates of lead-acid batteries. In each of several full-scale trials at automotive and industrial battery manufacturers, the simple replacement of 1wt.% of leady oxide with finely-divided tetrabasic lead sulfate (SureCure(TM) by Hammond Group Inc.) is shown to accelerate significantly the conversion of tribasic lead sulfate (3BS) to tetrabasic lead sulfate (4BS) in the curing process while improving crystal structure and reproducibility. Shorter curing times result in reduced labour and energy costs, as well as reduced fixed (curing chambers and plant footprint) and working (plate inventory) capital investment. (author)
A Study on Electric Power Smoothing System for Lead-Acid Battery of Stand-Alone Natural Energy Power System Using EDLC

Science.gov (United States)

Jia, Yan; Shibata, Ryosuke; Yamamura, Naoki; Ishida, Muneaki

To resolve energy shortage and global warming problem, renewable natural resource and its power system has been gradually generalizing. However, the power fluctuation suppressing in short period and the balance control of consumption and supply in long period are two of main problems that need to be resolved urgently in natural energy power system. In Stand-alone Natural Energy Power System (SNEPS) with power energy storage devices, power fluctuation in short period is one of the main reasons that recharge cycle times increase and lead-acid battery early failure. Hence, to prolong the service life of lead-acid battery and improve power quality through suppressing the power fluctuation, we proposed a method of electric power smoothing for lead-acid battery of SNEPS using bi-directional Buck/Boost converter and Electric Double Layer Capacitor (EDLC) in this paper. According to the test data of existing SNEPS, a power fluctuation condition is selected and as an example to analyze the validity of the proposed method. The analysis of frequency characteristics indicates the power fluctuation is suppressed a desired range in the target frequency region. The experimental results of confirmed the feasibility of the proposed system and the results well satisfy the requirement of system design.
Research, development and demonstration of lead-acid batteries for electric vehicle propulsion. Annual report, 1979

Energy Technology Data Exchange (ETDEWEB)

1980-06-01

This report describes work performed from October 1, 1978 to September 30, 1979. The approach for development of both the Improved State-of-the-Art (ISOA) and Advanced lead-acid batteries is three pronged. This approach concentrates on simultaneous optimization of battery design, materials, and manufacturing processing. The 1979 fiscal year saw the achievement of significant progress in the program. Some of the major accomplishments of the year are outlined. 33 figures, 13 tables. (RWR)

Lead-acid batteries in micro-hybrid applications. Part II. Test proposal

Energy Technology Data Exchange (ETDEWEB)

Schaeck, S.; Stoermer, A.O. [BMW Group, 80788 Muenchen (Germany); Albers, J. [Johnson Controls Power Solutions EMEA, 30419 Hannover (Germany); Weirather-Koestner, D. [ZSW Ulm, 89081 Ulm (Germany); Kabza, H. [Universitaet Ulm, Institut fuer Energiewandlung und -speicherung, 89081 Ulm (Germany)

2011-02-01

In the first part of this work selected key parameters for applying lead-acid (LA) batteries in micro-hybrid power systems (MHPS) were investigated. Main results are integrated in an accelerated, comprehensive test proposal presented here. The test proposal aims at a realistic representation of the pSoC operation regime, which is described in Refs. The test is designed to be sensitive with respect to dynamic charge acceptance (DCA) at partially discharged state (critical for regenerative braking) and the internal resistance at high-rate discharge (critical for idling stop applications). First results are presented for up-to-date valve-regulated LA batteries with absorbent glass mat (AGM) separators. The batteries are close to the limits of the first proposal of pass/fail-criteria. Also flooded batteries were tested; the first out of ten units failed already. (author)
Lead-acid batteries in micro-hybrid applications. Part II. Test proposal

Science.gov (United States)

Schaeck, S.; Stoermer, A. O.; Albers, J.; Weirather-Koestner, D.; Kabza, H.

In the first part of this work [1] selected key parameters for applying lead-acid (LA) batteries in micro-hybrid power systems (MHPS) were investigated. Main results are integrated in an accelerated, comprehensive test proposal presented here. The test proposal aims at a realistic representation of the pSoC operation regime, which is described in Refs. [1,6]. The test is designed to be sensitive with respect to dynamic charge acceptance (DCA) at partially discharged state (critical for regenerative braking) and the internal resistance at high-rate discharge (critical for idling stop applications). First results are presented for up-to-date valve-regulated LA batteries with absorbent glass mat (AGM) separators. The batteries are close to the limits of the first proposal of pass/fail-criteria. Also flooded batteries were tested; the first out of ten units failed already.
An averaging battery model for a lead-acid battery operating in an electric car

Science.gov (United States)

Bozek, J. M.

1979-01-01

A battery model is developed based on time averaging the current or power, and is shown to be an effective means of predicting the performance of a lead acid battery. The effectiveness of this battery model was tested on battery discharge profiles expected during the operation of an electric vehicle following the various SAE J227a driving schedules. The averaging model predicts the performance of a battery that is periodically charged (regenerated) if the regeneration energy is assumed to be converted to retrievable electrochemical energy on a one-to-one basis.
Influence of safety vlave pressure on gelled electrolyte valve-regulated lead/acid batteries under deep cycling applications

International Nuclear Information System (INIS)

Oh, Sang Hyub; Kim, Myung Soo; Lee, Jin Bok; Lee, Heung Lark

2002-01-01

Cycle life tests have been carried out to evaluate the influence of safety valve pressure on vlave regulated lead/acid batteries under deep cycling applications. Batteries were cycled at 5 hour rates at 100 % DOD, and safety valve pressure was set to 1.08 and 2.00 bar, respectively. The batteries lost 248.3 g of water for each case after about 1,200 cycles, but the cyclic performances of the batteries were comparable. Most of the gas of the battery during discharging was hydrogen, and the oxygen concentration increased to 18 % after 3 hours of charging. The micro structure of the positive active materials was completely changed and the corrosion layer of the positive grid was less than 50 μm, regardless of the pressure of the safety valve after cycle life tests. The cause of discharge capacity decrease was found to water loss and the shedding of the positive active materials. The pressure of safety valve does not give little effect to the cyclic performance and the failure modes of the gelled electrolyte valve-regulated lead acid batteries
Effects of calcium disodium EDTA and meso-2,3-dimercaptosuccinic acid on tissue concentrations of lead for use in treatment of calves with experimentally induced lead toxicosis.

Science.gov (United States)

Meldrum, James B; Ko, Kam W

2003-06-01

To compare the efficacy of calcium disodium EDTA (CaNa2EDTA) and meso-2,3-dimercaptosuccinic acid (DMSA) in reducing concentrations of lead in selected tissues for use in treatment of calves with experimentally induced lead toxicosis. 19 sexually intact male Holstein calves that weighed 35 to 60 kg. Calves were randomly assigned to 1 of 5 treatment groups: group 1, control calves; group 2, lead only; group 3, lead and EDTA; group 4, lead and DMSA; and group 5, lead, EDTA, and DMSA. Calves in groups 2 to 5 were dosed daily with lead (5 mg/kg, PO) for 10 days. Doses of EDTA (100 mg/kg) and DMSA (25 mg/kg) were administered IV once daily for 4 consecutive days beginning on day 11. Effects of the chelators on lead concentrations in the liver, kidneys, testes, muscles, bones, and brain were compared among the various groups. Compared with the effects of EDTA, DMSA greatly reduced lead concentrations in renal and hepatic tissues. We did not detect significant differences for the effects of EDTA or DMSA on lead concentrations in the testes; there was an adverse interaction of EDTA with DMSA that caused an increase in lead concentrations in the testes. DMSA is much more effective than EDTA in removing lead from renal and hepatic tissues in calves. Use of DMSA in calves with lead intoxication appears to be a viable treatment option. Combining DMSA and EDTA as a treatment modality in calves did not offer any advantages.
Lead Effect on Aminolevulinic Acid Dehydratase Activity of Feral Pigeon (Columba livia in Drenas

Directory of Open Access Journals (Sweden)

Albana Plakiqi Milaimi

2015-09-01

Full Text Available This study was aimed to investigate the effects of environmental pollution with heavy metals from ferro-nickel smelter on Aminolevulinic Acid Dehydratase (ALAD activity, and to analyze the blood lead level of feral pigeon (Columba livia in ferro-nickel smelter courtyard in Drenas City, Republic of Kosovo. For this purpose, twenty specimens of feral pigeon (20 birds, males and females, were collected in Drenas city which were living in ferro-nickel smelter courtyard, and 20 specimens in Lubizhdë village as control group (non-contaminated area. ALAD activity in Drenas group was significantly inhibited (P<0.001, compared with ALAD activity of controls. The blood lead level was significantly increased (P=0.015 compared to control group. Correlation between ALAD and blood lead level in Drenas group was negative (r=-0.117; P>0.050 and positive in Lubizhdë group (r=0.452; P> 0.050, but not in significant difference between the input groups. Feral pigeons can play an important role as bioindicators, which can used to monitor the environmental pollution with heavy metals that may originate from Nickel metallurgy.
Investigations on organolead compounds V. Lead---lead bond cleavage reactions of hexaphenyldilead

NARCIS (Netherlands)

Willemsens, L.C.; Kerk, G.J.M. van der

1968-01-01

It has been shown that a number of nucleophilic and weakly electrophilic reagents (organolithium and organomagnesium compounds, metallic lithium, potassium permanganate, sodium ethoxide, diaryl disulphides, sulphur, ozone, hypochlorous acid and iodine/iodide) selectively cleave the lead---lead bond
A broad look at separator material technology for valve-regulated lead/acid batteries

Energy Technology Data Exchange (ETDEWEB)

Zguris, G.C. [Hollingsworth and Vose, West Groton, MA (United States)

1998-05-18

Recent research has proved the importance of a constant force of 40 kPa or greater on the paste solidus-grid interface. This has lead to increased interest in re-examining the microglass separator and the system that the plate-separator interaction forms. This renewed interest has resulted in new separator ideas and the revisiting of concepts tried in the early days of valve-regulated lead/acid (VRLA) technology. The paper is divided into two parts. The first part examines some past separator developments that have been tried but are presently not accepted by the general VRLA community. This is due to the excellent performance of the microglass separator used so successfully during the last 20 years. Many fundamental questions that need to be asked regarding the selection of a new separator system have long ago been forgotten. The second part of the paper reviews some fundamental aspects of separator selection, and some important attributes that the separator must provide based on current knowledge of the separator system. Attributes such as toughness, corrosion resistance, compression, wicking, stratification, porosity and conformability are discussed. (orig.)
An Influence Study of Hydrogen Evolution Characteristics on the Negative Strap Corrosion of Lead Acid Battery

Directory of Open Access Journals (Sweden)

Zhong Guobin

2015-01-01

Full Text Available Negative strap corrosion is an important reason for the failure of valve regulated lead acid battery. This paper selected the Pb-Sb alloy material and Pb-Sn alloy material, made an investigation on the negative corrosion resistance and hydrogen evolution of these two alloy materials by scanning electron microscope analysis, metallographic analysis, chemical study and linear sweep voltammetry, and discussed the influence of lead alloy hydrogen evolution on the negative strap corrosion. The results showed that the hydrogen evolution reaction rates of the alloys had an impact on the corrosion areas with the maximum thickness of the alloys and the depth of corrosion layers. Greater hydrogen evolution reaction rate can lead to shorter distance between the corrosion area with the maximum thickness and the liquid level; whereas the greater corrosion layer thickness can bring aggravated risk of negative strap corrosion failure.
Molecular interaction of pinic acid with sulfuric acid

DEFF Research Database (Denmark)

Elm, Jonas; Kurtén, Theo; Bilde, Merete

2014-01-01

We investigate the molecular interactions between the semivolatile α-pinene oxidation product pinic acid and sulfuric acid using computational methods. The stepwise Gibbs free energies of formation have been calculated utilizing the M06-2X functional, and the stability of the clusters is evaluated...... cluster. The involvement of more than one pinic acid molecule in a single cluster is observed to lead to the formation of favorable (pinic acid)2(H2SO4) and (pinic acid)2(H2SO4)2 clusters. The identified most favorable growth paths starting from a single pinic acid molecule lead to closed structures...
High folic acid consumption leads to pseudo-MTHFR deficiency, altered lipid metabolism, and liver injury in mice12345

Science.gov (United States)

Christensen, Karen E; Mikael, Leonie G; Leung, Kit-Yi; Lévesque, Nancy; Deng, Liyuan; Wu, Qing; Malysheva, Olga V; Best, Ana; Caudill, Marie A; Greene, Nicholas DE

2015-01-01

Background: Increased consumption of folic acid is prevalent, leading to concerns about negative consequences. The effects of folic acid on the liver, the primary organ for folate metabolism, are largely unknown. Methylenetetrahydrofolate reductase (MTHFR) provides methyl donors for S-adenosylmethionine (SAM) synthesis and methylation reactions. Objective: Our goal was to investigate the impact of high folic acid intake on liver disease and methyl metabolism. Design: Folic acid–supplemented diet (FASD, 10-fold higher than recommended) and control diet were fed to male Mthfr+/+ and Mthfr+/− mice for 6 mo to assess gene-nutrient interactions. Liver pathology, folate and choline metabolites, and gene expression in folate and lipid pathways were examined. Results: Liver and spleen weights were higher and hematologic profiles were altered in FASD-fed mice. Liver histology revealed unusually large, degenerating cells in FASD Mthfr+/− mice, consistent with nonalcoholic fatty liver disease. High folic acid inhibited MTHFR activity in vitro, and MTHFR protein was reduced in FASD-fed mice. 5-Methyltetrahydrofolate, SAM, and SAM/S-adenosylhomocysteine ratios were lower in FASD and Mthfr+/− livers. Choline metabolites, including phosphatidylcholine, were reduced due to genotype and/or diet in an attempt to restore methylation capacity through choline/betaine-dependent SAM synthesis. Expression changes in genes of one-carbon and lipid metabolism were particularly significant in FASD Mthfr+/− mice. The latter changes, which included higher nuclear sterol regulatory element-binding protein 1, higher Srepb2 messenger RNA (mRNA), lower farnesoid X receptor (Nr1h4) mRNA, and lower Cyp7a1 mRNA, would lead to greater lipogenesis and reduced cholesterol catabolism into bile. Conclusions: We suggest that high folic acid consumption reduces MTHFR protein and activity levels, creating a pseudo-MTHFR deficiency. This deficiency results in hepatocyte degeneration, suggesting a 2
The effects of thiamin on lead metabolism: organ distribution of lead 203.

Science.gov (United States)

Kim, J S; Hamilton, D L; Blakley, B R; Rousseaux, C G

1992-01-01

The effect of thiamin on the organ distribution of lead was evaluated in CD-1 mice exposed intragastrically or intraperitoneally to a single dose of lead acetate (100 micrograms) containing 100 microCi lead 203. They were treated with either thiamin (25 or 50 mg/kg body weight), calcium ethylenediaminetetraacetic acid (CaEDTA) (50 mg/kg body weight), or combinations of thiamin and CaEDTA. The whole body retention and the organ distribution of lead 203 varied depending upon the route of lead administration, dose of thiamin and the specific treatment combination. Thiamin (25 or 50 mg/kg) treatment increased the whole body retention of both intragastric and intraperitoneal lead by approximately 10% in each instance. Calcium ethylenediaminetetraacetic acid, either alone or in combination with thiamin (50 mg/kg) reduced the whole body retention of lead by as much as 14% regardless of route of lead exposure. The relative retention of lead by the liver, kidney and spleen was greater in mice exposed to lead by the intragastric route. Regardless of route, CaEDTA in the combined treatment reduced the relative retention of lead in both the liver and kidney, whereas thiamin alone only reduced the retention of lead in the kidney. The results of this study indicate that thiamin in combination with CaEDTA alters the distribution and retention of lead in a manner which may have therapeutic application as it relates to chelation therapy. PMID:1423063
The importance of observation of structural changes of lead acid battery active mass in special applications in the mining industry

Directory of Open Access Journals (Sweden)

Jana Zimáková

2015-10-01

Full Text Available To be able to use lead acid batteries in particularly difficult conditions in the mining industry, it is very important to understand the events that occur during traction operation of mining carts, or auxiliary lighting. Failure of lead accumulators in the hazardous environments, where it is desired non-explosive embodiment, may have fatal consequences. The paper describes the possibility of observing changes in active materials at the microscopic level. The process of charging and discharging lead-acid accumulator has been described in many publications. The aim of this article is to supplement known information about a series of images and analysis that will accurately show progressive changes in the structure of the negative electrode. Negative electrodes are, at each cycle, charged and discharged under the same conditions, scanned with a scanning electron microscope, the elemental analysis (EDS is performed, and the size of the individual sulfate crystals is measured. Previously measured results indicate that during the charging the conversion of PbSO4 crystals into a charged form of the active mass is not complete, and there is a rapid increase in the size of lead sulfate crystals on the negative electrode. This article compares changes in electrode surface composition after two cycles. There is a clear loss of lead and, on the other hand, the visible growth of sulfur. This indicates progressive surface sulfation.
Lead recovery and glass microspheres synthesis from waste CRT funnel glasses through carbon thermal reduction enhanced acid leaching process.

Science.gov (United States)

Mingfei, Xing; Yaping, Wang; Jun, Li; Hua, Xu

2016-03-15

In this study, a novel process for detoxification and reutilization of waste cathode ray tube (CRT) funnel glass was developed by carbon thermal reduction enhanced acid leaching process. The key to this process is removal of lead from the CRT funnel glass and synchronous preparation of glass microspheres. Carbon powder was used as an isolation agent and a reducing agent. Under the isolation of the carbon powder, the funnel glass powder was sintered into glass microspheres. In thermal reduction, PbO in the funnel glass was first reduced to elemental Pb by carbon monoxide and then located on the surface of glass microspheres which can be removed easily by acid leaching. Experimental results showed that temperature, carbon adding amount and holding time were the major parameters that controlled lead removal rate. The maximum lead removal rate was 94.80% and glass microspheres that measured 0.73-14.74μm were obtained successfully by setting the temperature, carbon adding amount and holding time at 1200°C, 10% and 30min, respectively. The prepared glass microspheres may be used as fillers in polymer materials and abrasive materials, among others. Accordingly, this study proposed a practical and economical process for detoxification and recycling of waste lead-containing glass. Copyright © 2015 Elsevier B.V. All rights reserved.
Ellagic Acid: A Logical Lead for Drug Development?

Science.gov (United States)

Shakeri, Abolfazl; Zirak, Mohammad Reza; Sahebkar, Amirhossein

2018-01-01

Naturally occurring polyphenols are the subject of increasing attention due to their potent antioxidant activity and their marked effects on the prevention of various oxidative stress-associated diseases such as cancer. Ellagic acid (EA) is an herbal polyphenol that is structurally a condensed dimer of gallic acid. This review aims to provide a comprehensive and updated overview on the biological activities of EA and potential therapeutic applications. EA is found in fruits and nuts, either in the combined form with hexahydroxydiphenic acid or in the bound form (ellagitannins). EA exhibits many biological properties such as antioxidant, anti-diabetic, anticancer and apoptosis-inducing activities. These biological and pharmacological properties are relevant to the treatment of several human diseases. Owing to its multiple mechanisms of action, EA represents a potential therapeutic agent against human diseases particularly cancer. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Application of ionic liquids as an electrolyte additive on the electrochemical behavior of lead acid battery

Energy Technology Data Exchange (ETDEWEB)

Rezaei, Behzad; Mallakpour, Shadpour; Taki, Mahmood [Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111 (Iran)

2009-02-15

Ionic liquids (ILs) belong to new branch of salts with unique properties which their applications have been increasing in electrochemical systems especially lithium-ion batteries. In the present work, for the first time, the effects of four ionic liquids as an electrolyte additive in battery's electrolyte were studied on the hydrogen and oxygen evolution overpotential and anodic layer formation on lead-antimony-tin grid alloy of lead acid battery. Cyclic and linear sweep voltammetric methods were used for this study in aqueous sulfuric acid solution. The morphology of grid surface after cyclic redox reaction was studied using scanning electron microscopy. The results show that most of added ionic liquids increase hydrogen overpotential and whereas they have no significant effect on oxygen overpotential. Furthermore ionic liquids increase antimony dissolution that might be related to interaction between Sb{sup 3+} and ionic liquids. Crystalline structure of PbSO{sub 4} layer changed with presence of ionic liquids and larger PbSO{sub 4} crystals were formed with some of them. These additives decrease the porosity of PbSO{sub 4} perm selective membrane layer at the surface of electrode. Also cyclic voltammogram on carbon-PbO paste electrode shows that with the presence of ionic liquids, oxidation and reduction peak current intensively increased. (author)
Failure modes of valve-regulated lead-acid batteries for electric bicycle applications in deep discharge

Energy Technology Data Exchange (ETDEWEB)

Guo, Yonglang; Tang, Shengqun [College of Chemistry and Chemical Engineering, Fuzhou University, Fuzhou 350108 (China); Meng, Gang; Yang, Shijun [Hubei Camel Storage Battery Co. Ltd., Gucheng 441705 (China)

2009-06-01

The 36 or 48 V valve-regulated lead-acid (VRLA) battery packs have been widely applied to the power sources of electric bicycles or light electric scooters in China. The failure modes of the 12 V/10 Ah VRLA batteries have been studied by the cycle life test at C{sub 2} discharge rate and 100% depth of discharge (DOD). It indicates that the main cause of the battery failure in this cycle duty is the softening and shedding of positive active mass (PAM) rather than individual water loss, recombination efficiency or sulfation, etc. When the electrolyte saturation falls to a certain extent, the high oxygen recombination current leads to the depolarization of the negative plate and the shift of the positive plate to a higher potential. The violent oxygen evolution accelerates the softening of PAM and the end of cycle life. (author)
Forming lead-based anodes

Energy Technology Data Exchange (ETDEWEB)

Ogorodnichuk, V I; Voitsekhovich, R I

1972-01-01

Lead-based anodes can be produced by forming a layer of lead dioxide by chemical treatment in a solution of sulfuric acid in potassium permanganate at 80 to 100/sup 0/. The solution is mixed by compressed air. (RWR)
Modified performance test of vented lead acid batteries for stationary applications

International Nuclear Information System (INIS)

Uhlir, K.W.; Fletcher, R.J.

1995-01-01

The concept of a modified performance test for vented lead acid batteries in stationary applications has been developed by the IEEE Battery Working Group. The modified performance test is defined as a test in the ''as found'' condition of the battery capacity and its ability to provide a high rate, short duration load (usually the highest rate of the duty cycle) that will confirm the battery's ability to meet the critical period of the load duty cycle, in addition to determining its percentage of rated capacity. This paper will begin by reviewing performance and service test requirements and concerns associated with both types of tests. The paper will then discuss the rationale for developing a modified performance test along with the benefits that can be derived from performing a modified performance test in lieu of a capacity test and/or a service test. The paper will conclude with an example on how to apply a modified performance test and test acceptance criteria
Relation of fatty acid composition in lead-exposed mallards to fat mobilization, lipid peroxidation and alkaline phosphatase activity

Science.gov (United States)

Mateo, R.; Beyer, W.N.; Spann, J.W.; Hoffman, D.J.

2003-01-01

The increase of n-6 polyunsaturated fatty acids (PUFA) in animal tissues has been proposed as a mechanism of lead (Pb) poisoning through lipid peroxidation or altered eicosanoids metabolism. We have studied fatty acid (FA) composition in liver and brain of mallards (Anas platyrhynchos) feeding for 3 weeks on diets containing combinations of low or high levels of vitamin E (20 or 200 UI/kg) and Pb (0 or 2 g/kg). Saturated FA, n-6 PUFA and total concentrations of FA were higher in livers of Pb-exposed mallards, but not in their brains. The percentage of n-6 PUFA in liver and brain was slightly higher in Pb-exposed mallards. The increase of n-6 PUFA in liver was associated with decreased triglycerides and increased cholesterol in plasma, thus could be in part attributed to feed refusal and fat mobilization. The hepatic ratios between adrenic acid (22:4 n-6) and arachidonic acid (20:4 n-6) or between adrenic acid and linoleic acid (18:2 n-6) were higher in Pb exposed birds, supporting the existing hypothesis of increased fatty acid elongation by Pb. Among the possible consequences of increased n-6 PUFA concentration in tissues, we found increased lipid peroxidation in liver without important histopathological changes, and decreased plasma alkaline phosphatase activity that may reflect altered bone metabolism in birds.

Lead immobilization by geological fluorapatite and fungus Aspergillus niger.

Science.gov (United States)

Li, Zhen; Wang, Fuwei; Bai, Tongshuo; Tao, Jinjin; Guo, Jieyun; Yang, Mengying; Wang, Shimei; Hu, Shuijin

2016-12-15

Phosphate solubilizing fungi have high ability to secrete organic acids. In this study, fungus Aspergillus niger and geological fluorapatite were applied in lead remediation in aqueous solution. Formation and morphology of the lead minerals, e.g., pyromorphite and lead oxalate, were investigated by SEM, XRD, and ATR-IR. The total quantity of organic acids reached the maximum at the sixth day, which improved the concentration of soluble P up to ∼370mg/L from ∼0.4mg/L. The organic acids, especially the oxalic acid, enhance the solubility of fluorapatite significantly. The stable fluoropyromorphite [Pb 5 (PO 4 ) 3 F] is precipitated with the elevated solubility of fluorapatite in the acidic environment. Furthermore, A. niger grows normally with the presence of lead cations. It is shown that >99% lead cations can be removed from the solution. However, immobilization caused by the precipitation of lead oxalate cannot be ignored if the fungus A. niger was cultured in the Pb solution. This study elucidates the mechanisms of lead immobilization by FAp and A. niger, and sheds its perspective in lead remediation, especially for high Pb concentration solution. Copyright © 2016 Elsevier B.V. All rights reserved.
The effects of thiamin on lead metabolism: organ distribution of lead 203.

OpenAIRE

Kim, J S; Hamilton, D L; Blakley, B R; Rousseaux, C G

1992-01-01

The effect of thiamin on the organ distribution of lead was evaluated in CD-1 mice exposed intragastrically or intraperitoneally to a single dose of lead acetate (100 micrograms) containing 100 microCi lead 203. They were treated with either thiamin (25 or 50 mg/kg body weight), calcium ethylenediaminetetraacetic acid (CaEDTA) (50 mg/kg body weight), or combinations of thiamin and CaEDTA. The whole body retention and the organ distribution of lead 203 varied depending upon the route of lead a...
Assessment and Remediation of Lead Contamination in Senegal

OpenAIRE

Donald E. Jones, MS; Assane Diop, BS; Meredith Block, MPA; Alexander Smith-Jones, BS; Andrea Smith-Jones, MS

2011-01-01

Background. This paper describes the impact of improper used lead-acid battery (ULAB) handling and disposal. A specific case study is presented describing the field assessment and remediation of lead contamination in a community in Senegal where at least 18 children died from lead poisoning. Objectives. The assessment and remediation process utilized to address the Senegal lead contamination has been used as a model approach to solving used lead-acid battery (ULAB) contamination in other e...
Predicting state of charge of lead-acid batteries for hybrid electric vehicles by extended Kalman filter

International Nuclear Information System (INIS)

Vasebi, A.; Bathaee, S.M.T.; Partovibakhsh, M.

2008-01-01

This paper describes and introduces a new nonlinear predictor and a novel battery model for estimating the state of charge (SoC) of lead-acid batteries for hybrid electric vehicles (HEV). Many problems occur for a traditional SoC indicator, such as offset, drift and long term state divergence, therefore this paper proposes a technique based on the extended Kalman filter (EKF) in order to overcome these problems. The underlying dynamic behavior of each cell is modeled using two capacitors (bulk and surface) and three resistors (terminal, surface and end). The SoC is determined from the voltage present on the bulk capacitor. In this new model, the value of the surface capacitor is constant, whereas the value of the bulk capacitor is not. Although the structure of the model, with two constant capacitors, has been previously reported for lithium-ion cells, this model can also be valid and reliable for lead-acid cells when used in conjunction with an EKF to estimate SoC (with a little variation). Measurements using real-time road data are used to compare the performance of conventional internal resistance (R int ) based methods for estimating SoC with those predicted from the proposed state estimation schemes. The results show that the proposed method is superior to the more traditional techniques, with accuracy in estimating the SoC within 3%
Distribution of soil arsenic species, lead and arsenic bound to humic acid molar mass fractions in a contaminated apple orchard

International Nuclear Information System (INIS)

Newton, Kimberly; Amarasiriwardena, Dulasiri; Xing, Baoshan

2006-01-01

Excessive application of lead arsenate pesticides in apple orchards during the early 1900s has led to the accumulation of lead and arsenic in these soils. Lead and arsenic bound to soil humic acids (HA) and soil arsenic species in a western Massachusetts apple orchard was investigated. The metal-humate binding profiles of Pb and As were analyzed with size exclusion chromatography-inductively coupled plasma mass spectrometry (SEC-ICP-MS). It was observed that both Pb and As bind 'tightly' to soil HA molar mass fractions. The surface soils of the apple orchard contained a ratio of about 14:1 of water soluble As (V) to As (III), while mono-methyl (MMA) and di-methyl arsenic (DMA) were not detectable. The control soil contained comparatively very low levels of As (III) and As (V). The analysis of soil core samples demonstrated that As (III) and As (V) species are confined to the top 20 cm of the soil. - The distribution of arsenic species [i.e., As (III), As (V), and methylated arsenic species (DMA, MMA)] on the soil surface and in a depth profile as well as those associated with humic acids is discussed
SUNRAYCE 1993: Working safely with lead-acid batteries and photovoltaic power systems

Science.gov (United States)

Dephillips, M. P.; Moskowitz, P. D.; Fthenakis, V. M.

1992-11-01

The US Department of Energy (DOE) is sponsoring SUNRAYCE 93 to advance tile technology and use of photovoltaics and electric vehicles. Participants will use cars powered by photovoltaic modules and lead-acid storage batteries. This brochure, prepared for students and faculty participating in this race, outlines the health hazards presented by these electrical systems and gives guidance on strategies for their safe usage. At the outset, it should be noted that working with photovoltaic systems and batteries requires electric vehicle drivers and technicians to have 'hands-on' contact with the car on a daily basis. It is important that no one work near a photovoltaic energy system or battery, either in a vehicle or on the bench, unless they familiarize themselves with the components in use and know and observe safe work practices including the safety precautions described in the manuals provided by the various equipment vendors and this document.
Absorptive glass-mat separators for valve-regulated lead/acid batteries - thoughts on compression

Energy Technology Data Exchange (ETDEWEB)

Zguris, G.C. [Hovosorb Separators, Hollingsworth and Vose Co., West Groton, MA (United States)

1997-07-01

In the past few years valve-regulated lead/acid (VRLA) batteries have come under increased study. Their use has become more widespread, yet their expected life has not always been realized. This paper discusses some thoughts relating to the property of compression of the microglass separator and the impact of compression on VRLA battery life. Ideas are suggested for the design engineer to consider in selecting a battery separator. Additionally, several long-term battery separator tests are described. As more is learned about the complex interactions that are taking place in the VRLA recombination process, a greater appreciation is being given to the role of the separator. Today, battery designers can help improve expected battery performance by incorporating the latest information regarding battery separators, compression factors, and impact on life. (orig.)
Modelling the effect of temperature and free acid, silver, copper and lead concentrations on silver electrorefining electrolyte conductivity

OpenAIRE

Aji, Arif T.; Kalliomäki, Taina; Wilson, Benjamin P.; Aromaa, Jari; Lundström, Mari

2016-01-01

Conductivity is one of the key physico-chemical properties of electrolyte in silver electrorefining since it affects the energy consumption of the process. As electrorefining process development trends towards high current density operation, having electrolytes with high conductivities will greatly reduce the energy consumption of the process. This study outlines investigations into silver electrorefining electrolyte conductivity as a function of silver, free acid, copper and lead concentrati...
Understanding the function and performance of carbon-enhanced lead-acid batteries : milestone report for the DOE Energy Storage Systems program (FY11 Quarter 2: January through March 2011).

Energy Technology Data Exchange (ETDEWEB)

Shane, R. (East Penn Manufacturing, Lyon Station, PA); Enos, David George; Hund, Thomas D.

2011-05-01

This report describes the status of research being performed under CRADA No. SC10/01771.00 (Lead/Carbon Functionality in VRLA Batteries) between Sandia National Laboratories and East Penn Manufacturing, conducted for the U.S. Department of Energy's Energy Storage Systems Program. The Quarter 2 Milestone was completed on time. The milestone entails an ex situ analysis of the four carbons that have been added to the negative active material of valve-regulated lead-acid (VRLA) batteries for the purposes of this study. The four carbons selected for this study were a graphitic carbon, a carbon black, an activated carbon, and acetylene black. The morphology, crystallinity, and impurity contents of each of the four carbons were analyzed; results were consistent with previous data. Cycling on a subset of the received East Penn cells containing different carbons (and a control) has been initiated. Carbon has been explored as an addition to lead-acid battery electrodes in a number of ways. Perhaps the most notable to date has been the hybrid 'Ultrabattery' developed by CSIRO where an asymmetric carbon-based electrochemical capacitor is combined with a lead-acid battery into a single cell, dramatically improving high-rate partial-state-of-charge (HRPSoC) operation. As illustrated below, the 'Ultrabattery' is a hybrid device constructed using a traditional lead-acid battery positive plate (i.e., PbO{sub 2}) and a negative electrode consisting of a carbon electrode in parallel with a lead-acid negative plate. This device exhibits a dramatically improved cycle life over traditional VRLA batteries, as well as increased charge power and charge acceptance. The 'Ultrabattery' has been produced successfully by both The Furukawa Battery Co. and East Penn Manufacturing. An example illustrating the dramatic improvement in cycle life of the Ultrabattery over a conventional VRLA battery is shown.
Negative plate macropore surfaces in lead-acid batteries: Porosity, Brunauer-Emmett-Teller area, and capacity

Energy Technology Data Exchange (ETDEWEB)

D' Alkaine, C.V.; de O. Brito, G.A. [Group of Electrochemistry and Polymers, DQ-UFSCar, Rodovia Washington Luis, Km 235, CP 676, 13565-905 Sao Carlos (SP) (Brazil)

2009-06-01

We propose an explanation for the production of an electrochemically active area during the electrochemical formation of lead-acid battery negative plates based on solid-state reactions. Our proposal is supported by experimental data. This study includes a critical review of the literature on charge/discharge mechanisms, porosity, and BET area. The critical review, through the latter two parameters, indicates the existence of both macro and micropores in positive plates, but only macropores in negative plates, with characteristic surface roughness. In the present paper the surface sulfation of the precursor is controlled using various acidic, neutral and alkaline solutions during an electrochemical formation process that does not include soaking. Our results confirm that variable roughness can be produced at the negative plate macropore surfaces. The morphological changes produced by different formation conditions are assessed by measuring the macroporosity, BET area, and capacity of single negative plates. Based on these concepts, a method was developed and applied to measure independently the contributions of geometrical surface macroporosity and roughness to the negative plate capacity. (author)
Biomonitoring of lead-contaminated Missouri streams with an assay for erythrocyte δ-aminolevulinic acid dehydratase activity in fish blood

Science.gov (United States)

Schmitt, C.J.; Wildhaber, M.L.; Hunn, J.B.; Nash, T.; Tieger, M. N.; Steadman, B. L.

1993-01-01

The activity of the enzyme δ-aminolevulinic acid dehydratase (ALA-D) in erythrocytes has long been used as a biomarker of lead exposure in humans and waterfowl and, more recently, in fishes. The assay was tested for ALA-D activity in fishes from streams affected by lead in combination with other metals from lead-zinc mining and related activities. Fishes (mostly catostomids) were collected from sites affected by historic and current mining activities, and from sites considered to be unaffected by mining (reference sites). A group of potentially toxic elements was measured in blood and carcass samples of individual fish, as were ALA-D activity, total protein (TP), and hemoglobin (Hb) in blood. Concentrations of mining-related metals (lead, zinc, and cadmium) were significantly greater (P<0.05) in fish blood and carcass at sites affected by historic mining activities than at reference and active mining sites. When analyzed by multiple regression, ALA-D activity, Hb, and TP accounted for 66% of blood-lead and 69% of carcass-lead variability. Differences among species were small. ALA-D activity as a biomarker adequately distinguished sites affected by bioavailable environmental lead. Zinc was the only other metal that affected ALA-D activity; it appeared to ameliorate the inactivation of ALA-D by lead.
SUNRAYCE 93: Working safely with lead-acid batteries and photovoltaic power systems

Energy Technology Data Exchange (ETDEWEB)

DePhillips, M.P.; Moskowitz, P.D.; Fthenakis, V.M.

1992-11-03

The US Department of Energy (DOE) is sponsoring SUNRAYCE 93 to advance tile technology and use of photovoltaics and electric vehicles. Participants will use cars powered by photovoltaic modules and lead-acid storage batteries. This brochure, prepared for students and faculty participating in this race, outlines the health hazards presented by these electrical systems, and gives guidance on strategies for their safe usage. At the outset, it should be noted that working with photovoltaic systems and batteries requires electric vehicle drivers and technicians to have {open_quotes}hands-on{close_quotes} contact with the car on a daily basis. It is important that no one work near a photovoltaic energy system or battery, either in a vehicle or on the bench, unless they familiarize themselves with the components in use, and know and observe safe work practices including the safety precautions described in the manuals provided by the various equipment vendors and this document.
Phase transformations of high-purity PbI{sub 2} nanoparticles synthesized from lead-acid accumulator anodes

Energy Technology Data Exchange (ETDEWEB)

Malevu, T.D., E-mail: malevutd@ufs.ac.za; Ocaya, R.O.; Tshabalala, K.G.

2016-09-01

High-purity hexagonal lead iodide nanoparticles have been synthesized from a depleted sealed lead acid battery anode. The synthesized product was found to consist of the rare 6R polytype form of PbI{sub 2} that is thought to have good potential in photovoltaic applications. We investigate the effects of annealing time and post-melting temperature on the structure and optical properties using 1.5418 Å CuKα radiation. Photoluminescence measurements were done under 150 W/221 nm wavelength xenon excitation. Phase transformation was observed through XRD peaks when annealing time increased from 0.5–5 h. The nanoparticle grain size and inter-planar distance appeared to be independent of annealing time. PL measurements show three broad peaks in a range of 400 nm to 700 nm that are attributed to excitonic, donor–acceptor pair and luminescence bands from the deep levels.
Isolation of radioactive thallium from lead targets

International Nuclear Information System (INIS)

Kozlova, M.D.; Sevast'yanova, A.S.; Malinin, A.B.; Kurenkov, N.V.

1989-01-01

Two methods of thallium-201 preperation from Pb-targets irradiated with protons: precipitation-extraction (1) and extraction (2) - are developed. When the target irraiated is extracted during the time necessary for bismuth-201 transformation into lead-201, lead macroquantity containing lead-201 was separated from undesirable thallium radionuclides, which are formed in direct nuclear reactions. The lead fraction was extracted to accumulate thallium-201, and it was separated from lead mocroquantity. The target was dissolved in the nitric acid. The 1st method differs from the 2nd one by the fact that before thallium-201 extraction, lead was precipitaed by the nitric acid. The 1st method permits to separate thallium-201 with chemical yield not less than 90 %, the 2nd one - ≥95 %. 2 refs
Eryptosis in lead-exposed workers.

Science.gov (United States)

Aguilar-Dorado, Itzel-Citlalli; Hernández, Gerardo; Quintanar-Escorza, Martha-Angelica; Maldonado-Vega, María; Rosas-Flores, Margarita; Calderón-Salinas, José-Víctor

2014-12-01

Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8μg/dl) and non-exposed workers (4.2μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca(2+)]i and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca(2+)], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications. Copyright © 2014 Elsevier Inc. All rights reserved.
Activity of lead deposited in the tissues in conditions of occupational lead exposure

Energy Technology Data Exchange (ETDEWEB)

1974-01-01

The author measured urinary excretion of delta-aminolevulinic acid (ALA), coproporphyrins and lead, before and after administration of chelating agents (CaEDTA and D-penicillamine) to subjects presenting clinical symptoms of lead poisoning and workers occupationally exposed to lead. He found a great increase in lead following its mobilization in subjects with lead poisoning who had previously shown a high level of haemoglobin precursors and a low urinary lead level. In these subjects ALA excretion was proportional to the duration of exposure. A correlation was found between urinary ALA and coproporphyrins, on the one hand, and lead excretion after provocation, on the other. This suggests that the lead deposited in the tissues, as well as that in circulation, retains all its activity.
The Positive Environmental Contribution of Jarosite by Retaining Lead in Acid Mine Drainage Areas

Directory of Open Access Journals (Sweden)

Teresa Pereira da Silva

2011-05-01

Full Text Available Jarosite, KFe3(SO42(OH6, is a secondary iron sulphate often found in acid mine drainage (AMD environments, particularly in mining wastes from polymetallic sulphide ore deposits. Despite the negative environmental connotation usually ascribed to secondary sulphate minerals due to the release of hazardous elements to aquifers and soils, jarosite acts as an efficient remover and immobilizer of such metals, particularly lead. The mineral chemistry of jarosite is reviewed and the results of a Fe K-edge XANES (X-Ray Absorption Near-Edge Structure study of K-, Na- and Pb-jarosite are described and discussed within the context of the abandoned old mines of São Domingos and Aljustrel located in southern Portugal, in the Iberian Pyrite Belt (IPB.
Acidic environment leads to ROS-induced MAPK signaling in cancer cells.

Directory of Open Access Journals (Sweden)

Anne Riemann

Full Text Available Tumor micromilieu often shows pronounced acidosis forcing cells to adapt their phenotype towards enhanced tumorigenesis induced by altered cellular signalling and transcriptional regulation. In the presents study mechanisms and potential consequences of the crosstalk between extra- and intracellular pH (pH(e, pH(i and mitogen-activated-protein-kinases (ERK1/2, p38 was analyzed. Data were obtained mainly in AT1 R-3327 prostate carcinoma cells, but the principle importance was confirmed in 5 other cell types. Extracellular acidosis leads to a rapid and sustained decrease of pH(i in parallel to p38 phosphorylation in all cell types and to ERK1/2 phosphorylation in 3 of 6 cell types. Furthermore, p38 phosphorylation was elicited by sole intracellular lactacidosis at normal pH(e. Inhibition of ERK1/2 phosphorylation during acidosis led to necrotic cell death. No evidence for the involvement of the kinases c-SRC, PKC, PKA, PI3K or EGFR nor changes in cell volume in acidosis-induced MAPK activation was obtained. However, our data reveal that acidosis enhances the formation of reactive oxygen species (ROS, probably originating from mitochondria, which subsequently trigger MAPK phosphorylation. Scavenging of ROS prevented acidosis-induced MAPK phosphorylation whereas addition of H(2O(2 enhanced it. Finally, acidosis increased phosphorylation of the transcription factor CREB via p38, leading to increased transcriptional activity of a CRE-reporter even 24 h after switching the cells back to a normal environmental milieu. Thus, an acidic tumor microenvironment can induce a longer lasting p38-CREB-medited change in the transcriptional program, which may maintain the altered phenotype even when the cells leave the tumor environment.
CADMIUM AND LEAD STATUS IN CORN HYBRIDS GROWN ON ACID SOIL OF EASTERN CROATIA

Directory of Open Access Journals (Sweden)

V. Kovačević

2002-06-01

Full Text Available Twenty corn (Zea mays L. hybrids were grown under field conditions in the west part of Brodsko-posavska county in Eastern Croatia during 2000 and 2001 growing seasons. The field trial was conducted in four replicates. The ear-leaf at beginning of silking stage (the second decade of July was taken for chemical analysis from each plot. Mean soil sample was taken by auger to 30 cm of depth. The total amounts of Cd and Pb in corn leaves were measured by ICP-AES technique after their microwave digestion using concentrated HNO3+H2O2. Mobile fraction of these elements in soil was extracted by ammonium acetate-EDTA solution. The experimental field is acid hydromorphic soil (locality Malino with moderate levels of mobile fractions of calcium, magnesium and aluminum. Also, mobile fraction of cadmium and lead are tolerable for growing of health food. Weather conditions during the study differed from the long-term mean. Low rainfall quantities during 5-months period and the higher air-temperatures characterized the 2000 growing season. Excess of rainfall in June and September, their shortage in July and August, as well as high temperatures in August, are main characteristics of weather during the corn growing seasons in 2001. Mean concentrations of cadmium and lead in corn leaves in our investigations were 0.14 ppm Cd and 0.420 ppm Pb. These amounts are low and not dangerous for plants, because critical concentrations of Cd and Pb in plants ranged from 5 to 10 ppm Cd and 10-20 ppm Pb. Considerable differences of cadmium and lead status in the ear-leaf were found among tested corn hybrids. For example, genetically induced differences from 0.07 to 0.21 ppm Cd were found, while these values for Pb were from 0.241 to 0.569 ppm Pb. Especially low Cd concentrations were found in six corn hybrids (OsSK373, E9917/99, Bc278, OsSK2-191, OsSK382 and Clarica: mean 0.092 ppm Cd, while in three hybrids it was considerably higher, but acceptable from the aspect of plant
Remediation of lead-contaminated soils

International Nuclear Information System (INIS)

Peters, R.W.; Shem, L.

1992-01-01

Excavation and transport of soil contaminated with heavy metals has generally been the standard remediation technique for treatment of heavy-metal-contaminated soils. This approach is not a permanent solution; moreover, off-site shipment and disposal of contaminated soil involves high expense, liability, and appropriate regulatory approval. Recently, a number of other techniques have been investigated for treating such contaminated sites, including flotation, solidification/stabilization, vitrification, and chemical extraction. This paper reports the results of a laboratory investigation determining the efficiency of using chelating agents to extract lead from contaminated soils. Lead concentrations in the soils ranged from 500 to 10,000 mg/kg. Ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA) were examined for their potential extractive capabilities. Concentrations of the chelating agents ranged from 0.01 to 0.10 M. The pH of the suspensions in which the extractions were performed ranged from 4 to 12. Results showed that the removal of lead using NTA and water was ph-dependent, whereas the removal of lead using EDTA was ph-insensitive. Maximum removals of lead were 68.7%,19.1%, and 7.3% using EDTA, NTA, and water, respectively (as compared with initial lead concentrations)

Lead poisoning from souvenir earthenware.

Science.gov (United States)

Hellström-Lindberg, Eva; Björklund, Andreas; Karlson-Stiber, Christine; Harper, Pauline; Seldén, Anders I

2006-02-01

A case of massive lead poisoning from juice contained in a Greek earthenware jug as well as six satellite cases of high lead exposure of similar origin is reported. The intoxicated patient was successfully treated with dimercaptosuccinic acid. Ceramic producers should adhere to the longstanding European legislation.
COBAT: collection and recycling spent lead/acid batteries in Italy

Science.gov (United States)

Sancilio, Cosmo

The European Economic Community (EEC) introduced a very clear Directive (157/91) aimed at solving the problem of collecting and recycling scrap accumulators and lead/acid batteries. This waste has a potentially harmful effect on the environment if the recycling process is not carried out correctly at all stages. COBAT is a Consortium created in 1990 in order to meet the requirements of the Italian law 475/88 which preceded the above-mentioned EEC Directive. This Consortium has a broad basis comprising all sectors involved in the battery cycle life (battery producers, battery fitters, collectors and recyclers). So far the organization, using the following approach has had very positive results since its inception three years ago. The public sector, representatives from the Environmental Ministry and the Ministry of Industry are responsible for supplying guidelines and the overall supervision, whereas the private sector is in charge of the organization and the enforcement of the law. This paper explains in detail the structure and tasks of COBAT, and will proceed on to explain how COBAT is organized and how the collection network and recycling plants work. The economical aspects will be examined in detail, and emphasis will be put on how little the public will have to pay in order to safeguard the environment, and the harmful effect of a competitively run regime to the ecosystem.
System dynamic model and charging control of lead-acid battery for stand-alone solar PV system

KAUST Repository

Huang, B.J.

2010-05-01

The lead-acid battery which is widely used in stand-alone solar system is easily damaged by a poor charging control which causes overcharging. The battery charging control is thus usually designed to stop charging after the overcharge point. This will reduce the storage energy capacity and reduce the service time in electricity supply. The design of charging control system however requires a good understanding of the system dynamic behaviour of the battery first. In the present study, a first-order system dynamics model of lead-acid battery at different operating points near the overcharge voltage was derived experimentally, from which a charging control system based on PI algorithm was developed using PWM charging technique. The feedback control system for battery charging after the overcharge point (14 V) was designed to compromise between the set-point response and the disturbance rejection. The experimental results show that the control system can suppress the battery voltage overshoot within 0.1 V when the solar irradiation is suddenly changed from 337 to 843 W/m2. A long-term outdoor test for a solar LED lighting system shows that the battery voltage never exceeded 14.1 V for the set point 14 V and the control system can prevent the battery from overcharging. The test result also indicates that the control system is able to increase the charged energy by 78%, as compared to the case that the charging stops after the overcharge point (14 V). © 2010 Elsevier Ltd. All rights reserved.
Removal lead (Pb and mercury (Hg from juaro fish (Pangasius polyuranodon using citric acid from pineapple extract (Ananas comosus as chelating agent

Directory of Open Access Journals (Sweden)

Pra Dian Mariadi

2017-10-01

Full Text Available An assessment of dietary risk of heavy metals exposure to human is important since it is the main of exposure. The aim of study to measure the contamination of lead and mercury in juaro fish meat and the effort to reduce contaminations using citric acid from pineapple extract as a chelating agent. Samples was soaked and boiled in citric acid extract at concentration 50%, 75 %, 100 % for, 15 min, 30 min, 45 min at 25 0C, 50 0C and 100 0C. The concentration of lead and mercury in Juaro fish lower than the maximum acceptable lever for Pb and Hg respectively (1mg/kg for Pb, 0,5 mg/Kg for Hg. The result indicated that after soaking and boiling in citric acid solution form pineapple extract at concentration 100 % for 45 min at 100 0C reducing heavy metals Pb from 0,02 mg.Kg-1 to 0,003 mg.Kg-1 and Hg from 0,011 mg.Kg-1 to lower than 0,0001 mg.Kg-1. The increasing of soaking time and boiling temperature, the levels of Pb and Hg in Juaro fish Tissue will decreasing.
Sex differences in amino acids lost via sweating could lead to differential susceptibilities to disturbances in nitrogen balance and collagen turnover.

Science.gov (United States)

Dunstan, R H; Sparkes, D L; Dascombe, B J; Stevens, C J; Murphy, G R; Macdonald, M M; Gottfries, J; Gottfries, C-G; Roberts, T K

2017-08-01

Fluid collected during sweating is enriched with amino acids derived from the skin's natural moisturising factors and has been termed "faux" sweat. Little is known about sex differences in sweat amino acid composition or whether faux sweat amino acid losses affect nitrogen balance. Faux sweat collected by healthy adults (n = 47) after exercise, and at rest by chronic fatigue patients, was analysed for amino acid composition. Healthy females had higher total amino acid concentrations in sweat (10.5 ± 1.2 mM) compared with healthy males (6.9 ± 0.9 mM). Females had higher levels of 13 amino acids in sweat including serine, alanine and glycine. Higher hydroxyproline and proline levels suggested greater collagen turnover in females. Modelling indicated that with conservative levels of exercise, amino acid losses in females via faux sweat were triple than those predicted for urine, whereas in males they were double. It was concluded that females were more susceptible to key amino acid loss during exercise and/or hot conditions. Females reporting chronic fatigue had higher levels of methionine in faux sweat than healthy females. Males reporting chronic fatigue had higher levels of numerous amino acids in faux sweat compared to healthy males. Higher amino acid loss in faux sweat associated with chronic fatigue could contribute to a hypometabolic state. Depending on activity levels, climatic conditions and gender, amino acid losses in sweat and skin leachate could influence daily protein turnover where periods of continuously high turnover could lead to a negative net nitrogen balance.
Understanding the function and performance of carbon-enhanced lead-acid batteries : milestone report for the DOE Energy Storage Systems program (FY11 Quarter 1: October through December 2010).

Energy Technology Data Exchange (ETDEWEB)

Shane, R. (East Penn Manufacturing, Lyon Station, PA); Enos, David George; Hund, Thomas D.

2011-05-01

This report describes the status of research being performed under CRADA No. SC10/01771.00 (Lead/Carbon Functionality in VRLA Batteries) between Sandia National Laboratories and East Penn Manufacturing, conducted for the U.S. Department of Energy's Energy Storage Systems Program. The Quarter 1 Milestone was completed on time. The milestone entails conducting a thorough literature review to establish the current level of understanding of the mechanisms through which carbon additions to the negative active material improve valve-regulated lead-acid (VRLA) batteries. Most studies have entailed phenomenological research observing that the carbon additions prevent/reduce sulfation of the negative electrode; however, no understanding is available to provide insight into why certain carbons are successful while others are not. Impurities were implicated in one recent review of the electrochemical behavior of carbon additions. Four carbon samples have been received from East Penn Manufacturing and impurity contents have been analyzed. Carbon has been explored as an addition to lead-acid battery electrodes in a number of ways. Perhaps the most notable to date has been the hybrid 'Ultrabattery' developed by CSIRO where an asymmetric carbon-based electrochemical capacitor is combined with a lead-acid battery into a single cell, dramatically improving high-rate partial-state-of-charge (HRPSoC) operation. As illustrated below, the 'Ultrabattery' is a hybrid device constructed using a traditional lead-acid battery positive plate (i.e., PbO{sub 2}) and a negative electrode consisting of a carbon electrode in parallel with a lead-acid negative plate. This device exhibits a dramatically improved cycle life over traditional VRLA batteries, as well as increased charge power and charge acceptance. The 'Ultrabattery' has been produced successfully by both The Furukawa Battery Co. and East Penn Manufacturing. An example illustrating the dramatic
Mechanism of action of electrochemically active carbons on the processes that take place at the negative plates of lead-acid batteries

Energy Technology Data Exchange (ETDEWEB)

Pavlov, D.; Rogachev, T.; Nikolov, P.; Petkova, G. [Institute of Electrochemistry and Energy Systems, Bulgarian Academy of Sciences, Acad. G. Bonchev Street, bl. 10, Sofia 1113 (Bulgaria)

2009-06-01

It is known that negative plates of lead-acid batteries have low charge acceptance when cycled at high rates and progressively accumulate lead sulphate on high-rate partial-state-of-charge (HRPSoC) operation in hybrid-electric vehicle (HEV) applications. Addition of some carbon or graphite forms to the negative paste mix improves the charge efficiency and slows down sulfation of the negative plates. The present investigation aims to elucidate the contribution of electrochemically active carbon (EAC) additives to the mechanism of the electrochemical reactions of charge of the negative plates. Test cells are assembled with four types of EAC added to the negative paste mix in five different concentrations. Through analysis of the structure of NAM (including specific surface and pore radius measurements) and of the electrochemical parameters of the test cells on HRPSoC cycling, it is established that the electrochemical reaction of charge Pb{sup 2+} + 2e{sup -} {yields} Pb proceeds at 300-400 mV lower over-potentials on negative plates doped with EAC additives as compared to the charge potentials of cells with no carbon additives. Hence, electrochemically active carbons have a highly catalytic effect on the charge reaction and are directly involved in it. Consequently, the reversibility of the charge/discharge processes is improved, which eventually leads to longer battery cycle life. Thus, charging of the negative plates proceeds via a parallel mechanism on the surfaces of both Pb and EAC particles, at a higher rate on the EAC phase. Cells with EAC in NAM have the longest cycle life when their NAM specific surface is up to 4 m{sup 2} g{sup -1} against 0.5 m{sup 2} g{sup -1} for the lead surface. The proposed parallel mechanism of charge is verified experimentally on model Pb/EAC/PbSO{sub 4} and Pb/EAC electrodes. During the charge and discharge cycles of the HRPSoC test, the EAC particles are involved in dynamic adsorption/desorption on the lead sulfate and lead
Health risk assessment of various metal(loid)s via multiple exposure pathways on children living near a typical lead-acid battery plant, China

International Nuclear Information System (INIS)

Cao, Suzhen; Duan, Xiaoli; Zhao, Xiuge; Wang, Beibei; Ma, Jin; Fan, Delong; Sun, Chengye; He, Bin; Wei, Fusheng; Jiang, Guibin

2015-01-01

Manufacture of lead-acid batteries is of widespread interest because of its emissions of heavy metals and metalloids into environment, harming environmental quality and consequently causing detrimental effects on human health. In this study, exposure pathways and health risks of children to heavy metal(loid)s (Pb, Cd, As, etc) were investigated based on field sampling and questionnaire. Pb was one of the most abundant elements in children's blood, with an elevated blood lead level of 12.45 μg dL −1 . Soil/dust and food were heavily polluted by targeted metal(loid)s. Food ingestion accounted for more than 80% of the total exposure for most metal(loid)s. The non-cancer risks to children were 3–10 times higher than the acceptable level of 1, while the cancer risks were 5–200 times higher than the maximum acceptable level of 1.0 × 10 −4 . The study emphasized the significance of effective environmental management, particularly to ensure food security near battery facilities. - Highlights: • The health risks of children living around a typical lead-acid battery was analyzed. • The exposure pathways of children to 12 heavy metal(loid)s were assessed. • Courtyard soil and indoor dust and duplicate food were contaminated by metal(loid)s. • Food ingestion was the major pathway for children's exposure to most metal(loid)s. • Higher potentially non-cancer and cancer risks happened to the local children. - The children living around a typical lead-acid battery plant suffered from serious health risks, which mainly attributed to food ingestion and air inhalation exposure
Blood Lead Level and Δ-Aminolevulinic Acid Dehydratase Activity in Pre-Menopausal and Postmenopausal Women

Directory of Open Access Journals (Sweden)

I.R Elezaj

2012-07-01

Full Text Available To describe the relationship of blood lead levels (BLL and blood, δ-aminolevulinic acid dehydratase(ALAD activity and haematocrit value(Hct to menopause , were examined 17 pre-or perimenopausal (PreM and 17 postmenopausal women (PosMfrom Prishtina City, the capital ofRepublic Kosovo. The mean age of the PreM women was 28.8 years (21-46, with a mean blood lead level of 1.2 μg/dL (SD=0.583 μg/dL , the mean blood ALAD activity53.2 U/LE (SD= 2.8 U/LE and haematocrit value42.1 % (SD= 4.3 %. The mean age of the PosM women was 53.6 years (43-67, with a mean blood lead level1.9 μg/dL (SD=0.94 μg/dL, the mean blood ALAD activity 44.4 U/LE(SD=7.2 U/LE and haematocrit value 42.1 % ( SD= 4.3 % and 42.2 % (SD=4.4 %. The BPb level of PosM women was significantly higher (P<0.001 in comparison with the BPb level in PreM women. The blood ALAD activity of PosM was significantly inhibited (P<0.002 in comparison with blood ALAD activity in PreM women. The haematocrit values were relatively unchanged. There was established significantly negative correlation between BPb and blood ALAD activity (r=- 0.605; P<0.01 in the PreM women.These results support the hypothesis that release of bone lead stores increases during menopause and constitutes an internal source of exposure possibly associated with adverse health effects on women in menopause transition.
Behavior of active deposit of lead (Teisinger) in the Japanese free from occupational exposure to lead

Energy Technology Data Exchange (ETDEWEB)

Araki, S

1973-12-01

Intravenous infusion of calcium disodium ethylenediamine tetraacetate (CaEDTA) was given to 45 Japanese adults without occupational exposure to lead for 1 hr at a dosage of 20 mg/kg body weight in 250 ml of 5 percent glucose solution. The urinary excretion of lead was estimated for 24 hr before, and for 2 hr and 24 hr after the administration. The least variation of the lead content was recognized in the 24-hour urinary excretion after the injection of CaEDTA. No sexual difference was noted in the creatinine-corrected lead concentration. By multiple linear regression and correlation analyses, age was found to be significant in determining positively the lead level mobilized in 24-hour urine samples. Height was significant in determining positively the spontaneous 24-hour urinary lead excretion. Certain significant correlations existed among lead in blood, delta-aminolevulinic acid dehydratase in erythrocytes, delta-aminolevulinic acid in urine, coproporphyrin in urine, lead in urine, and lead mobilized by CaEDTA. The existence of active body burden of lead was suggested in human subjects under usual urban conditions where the total ambient lead concentration averaged 1.7 micrograms/cm m of air. Based on a few assumptions, it was calculated that about 3 micrograms of lead was retained on the average per day by a Japanese adult. Daily retention of lead by Japanese adults was formularized as lead in micrograms equals a constant (K) times daily creatinine excretion in grams, where K is 1.77 in men and 2.73 in women. (Air Pollut. Abstr.)
Eryptosis in lead-exposed workers

International Nuclear Information System (INIS)

Aguilar-Dorado, Itzel-Citlalli; Hernández, Gerardo; Quintanar-Escorza, Martha-Angelica; Maldonado-Vega, María; Rosas-Flores, Margarita; Calderón-Salinas, José-Víctor

2014-01-01

Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8 μg/dl) and non-exposed workers (4.2 μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca 2+ ] i and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (< 0.1%), but lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca 2+ ], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications. - Graphical abstract: Fig. 1. (A) Blood lead concentration (PbB) and (B) phosphatidylserine externalization on erythrocyte membranes of non-lead exposed (□) and lead exposed workers (■). Values are mean ± SD. *Significantly different (P < 0.001). - Highlights: • Erythrocytes of lead exposed workers showed higher PS
Eryptosis in lead-exposed workers

Energy Technology Data Exchange (ETDEWEB)

Aguilar-Dorado, Itzel-Citlalli [Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico); Hernández, Gerardo [Section of Methodology of Science, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico); Quintanar-Escorza, Martha-Angelica [Faculty of Medicine, UJED, Durango, DGO (Mexico); Maldonado-Vega, María [CIATEC, León, GTO (Mexico); Rosas-Flores, Margarita [Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico); Calderón-Salinas, José-Víctor, E-mail: jcalder@cinvestav.mx [Biochemistry Department, Centro de Investigación y Estudios Avanzados IPN, México, DF (Mexico)

2014-12-01

Eryptosis is a physiological phenomenon in which old and damaged erythrocytes are removed from circulation. Erythrocytes incubated with lead have exhibited major eryptosis. In the present work we found evidence of high levels of eryptosis in lead exposed workers possibly via oxidation. Blood samples were taken from 40 male workers exposed to lead (mean blood lead concentration 64.8 μg/dl) and non-exposed workers (4.2 μg/dl). The exposure to lead produced an intoxication characterized by 88.3% less δ-aminolevulinic acid dehydratase (δALAD) activity in lead exposed workers with respect to non-lead exposed workers. An increment of oxidation in lead exposed workers was characterized by 2.4 times higher thiobarbituric acid-reactive substance (TBARS) concentration and 32.8% lower reduced/oxidized glutathione (GSH/GSSG) ratio. Oxidative stress in erythrocytes of lead exposed workers is expressed in 192% higher free calcium concentration [Ca{sup 2+}]{sub i} and 1.6 times higher μ-calpain activity with respect to non-lead exposed workers. The adenosine triphosphate (ATP) concentration was not significantly different between the two worker groups. No externalization of phosphatidylserine (PS) was found in non-lead exposed workers (< 0.1%), but lead exposed workers showed 2.82% externalization. Lead intoxication induces eryptosis possibly through a molecular pathway that includes oxidation, depletion of reduced glutathione (GSH), increment of [Ca{sup 2+}], μ-calpain activation and externalization of PS in erythrocytes. Identifying molecular signals that induce eryptosis in lead intoxication is necessary to understand its physiopathology and chronic complications. - Graphical abstract: Fig. 1. (A) Blood lead concentration (PbB) and (B) phosphatidylserine externalization on erythrocyte membranes of non-lead exposed (□) and lead exposed workers (■). Values are mean ± SD. *Significantly different (P < 0.001). - Highlights: • Erythrocytes of lead exposed workers
Air pollution from lead added to gasoline

Energy Technology Data Exchange (ETDEWEB)

Dingeon, B; Collombel, C

1973-01-01

General hygienic and toxicological problems of lead added to gasoline are discussed. Lead emitted by motor vehicles pollutes the air especially in cities and along highways, and is accumulated by soil and plants. The lead levels found in the blood of subjects living in cities and near highways was significantly higher than in rural dwellers. Close correlation between the atmospheric lead concentration and the carbon monoxide concentration as well as the traffic density was established, indicating traffic as the source of atmospheric lead. The effect of traffic on the atmospheric lead concentration extended over a distance of up to 4 km. The lead, emitted by motor vehicles in the form of submicron particles, is retained in the organism at rates of 5-10 percent following ingestion, and at rates of 30-50 percent when inhaled. Lead is partially excreted by the liver, kidney, hair, and nails. Some 95 percent of the retained lead is found in the blood, and accumulation in the bones with potential mobilization due to increases in the corticosteroid level was observed. Exposure to lead can be diagnosed by basophil granulation test, urine delta-aminolevulinic acid test, and delta-aminolevulinic acid dehydratase test.
Anomalous bioaccumulation of lead in the earthworm Eisenoides lonnbergi (Michaelsen)

Science.gov (United States)

Beyer, W. Nelson; Codling, Eton E.; Rutzke, Michael A.

2018-01-01

Lead concentrations in soil organisms are usually well below those in the associated soil and tend to decrease with each higher trophic level in a food chain. Earthworms of the species Eisenoides lonnbergi provide an exception to this observation, accumulating very high concentrations of lead from acidic soils. Earthworms belonging to this species were collected from strongly to extremely acidic soils at 16 sites on a wildlife refuge in Maryland, USA. A lead concentration as high as 766 mg/kg, dry weight, was detected in depurated E. lonnbergi collected from soil containing only 17 mg/kg of lead. Concentration factors (ratio of lead concentration in earthworms to lead concentration in soil, dry wt) were highly variable at the sites, from 1.0 to 83. As suggested previously, lead absorption by earthworms is enhanced in low-calcium soils. The anomalously high concentrations of lead found in E. lonnbergi are more closely correlated with the uptake of calcium from acidic soils than with bioaccessibility of soil lead.
The use of castor oil and ricinoleic acid in lead chalcogenide nanocrystal synthesis

Science.gov (United States)

Kyobe, Joseph W. M.; Mubofu, Egid B.; Makame, Yahya M. M.; Mlowe, Sixberth; Revaprasadu, Neerish

2016-08-01

A green solution-based thermolysis method for the synthesis of lead chalcogenide (PbE, E = S, Se, Te) nanocrystals in castor oil (CSTO) and its isolate ricinoleic acid (RA) is described. The blue shift observed from the optical spectra of CSTO and RA-capped PbE nanocrystals (NCs) confirmed the evidence of quantum confinement. The dimensions of PbE NCs obtained from NIR absorption spectra, transmission electron microscopy (TEM), and X-ray diffraction (XRD) studies were in good agreement. The particle sizes estimated were in the range of 20, 25, and 130 nm for castor oil-capped PbS, PbSe, and PbTe, respectively. Well-defined close to cubic-shaped particles were observed in the scanning electron microscopy (SEM) images of PbSe and PbTe nanocrystals. The high-resolution TEM and selective area electron diffraction (SAED) micrographs of the as-synthesized crystalline PbE NCs showed distinct lattice fringes with d-spacing distances corroborating with the standard values reported in literature.
Studies on mathematical modeling of the leaching process in order to efficiently recover lead from the sulfate/oxide lead paste.

Science.gov (United States)

Buzatu, Traian; Ghica, Gabriel Valeriu; Petrescu, Ionuţ Mircea; Iacob, Gheorghe; Buzatu, Mihai; Niculescu, Florentina

2017-02-01

Increasing global lead consumption has been mainly supported by the acid battery manufacturing industry. As the lead demand will continue to grow, to provide the necessary lead will require an efficient approach to recycling lead acid batteries. In this paper was performed a mathematical modeling of the process parameters for lead recovery from spent lead-acid batteries. The results of the mathematical modeling compare well with the experimental data. The experimental method applied consists in the solubilisation of the sulfate/oxide paste with sodium hydroxide solutions followed by electrolytic processing for lead recovery. The parameters taken into considerations were NaOH molarity (4M, 6M and 8M), solid/liquid ratio - S/L (1/10, 1/30 and 1/50) and temperature (40°C, 60°C and 80°C). The optimal conditions resulted by mathematical modeling of the electrolytic process of lead deposition from alkaline solutions have been established by using a second-order orthogonal program, in order to obtain a maximum efficiency of current without exceeding an imposed energy specific consumption. The optimum value for the leaching recovery efficiency, obtained through mathematical modeling, was 89.647%, with an error of δ y =3.623 which leads to a maximum recovery efficiency of 86.024%. The optimum values for each variable that ensure the lead extraction efficiency equal to 89.647% are the following: 3M - NaOH, 1/35 - S/L, 70°C - temperature. Copyright © 2016 Elsevier Ltd. All rights reserved.
Levels and source apportionment of children's lead exposure: Could urinary lead be used to identify the levels and sources of children's lead pollution?

International Nuclear Information System (INIS)

Cao, Suzhen; Duan, Xiaoli; Zhao, Xiuge; Wang, Beibei; Ma, Jin; Fan, Delong; Sun, Chengye; He, Bin; Wei, Fusheng; Jiang, Guibin

2015-01-01

As a highly toxic heavy metal, the pollution and exposure risks of lead are of widespread concern for human health. However, the collection of blood samples for use as an indicator of lead pollution is not always feasible in most cohort or longitudinal studies, especially those involving children health. To evaluate the potential use of urinary lead as an indicator of exposure levels and source apportionment, accompanying with environmental media samples, lead concentrations and isotopic measurements (expressed as 207 Pb/ 206 Pb, 208 Pb/ 206 Pb and 204 Pb/ 206 Pb) were investigated and compared between blood and urine from children living in the vicinities of a typical coking plant and lead-acid battery factory. The results showed urinary lead might not be a preferable proxy for estimating blood lead levels. Fortunately, urinary lead isotopic measurements could be used as an alternative for identifying the sources of children's lead exposure, which coincided well with the blood lead isotope ratio analysis. - Highlights: • Pb isotopes of environmental media and children's blood and urine were analyzed. • Pb exposure and pollution source were studied in lead-acid battery and coking areas. • Pb isotope ratios in blood and urine were similar to those of food, water and PM. • Urine Pb level may not be used as a proxy for indicating the lead levels in blood. • Urine Pb isotope ratios is an alternative to identify source and exposure pathways. - Urinary lead is not a preferable proxy to estimate blood lead level, but urinary lead isotope ratios could be an alternative for identifying the sources of lead exposure in children
Lead distribution in soils impacted by a secondary lead smelter: Experimental and modelling approaches

Energy Technology Data Exchange (ETDEWEB)

Schneider, Arnaud R., E-mail: arnaud.schneider@univ-reims.fr [GEGENAA, EA 3795, Université de Reims Champagne-Ardenne, SFR Condorcet FR CNRS 3417, 2 esplanade Roland Garros, 51100 Reims (France); Cancès, Benjamin; Ponthieu, Marie [GEGENAA, EA 3795, Université de Reims Champagne-Ardenne, SFR Condorcet FR CNRS 3417, 2 esplanade Roland Garros, 51100 Reims (France); Sobanska, Sophie [Laboratoire de Spectrochimie IR et Raman, UMR-CNRS 8516, Bât. C5 Université de Lille I, 59655 Villeneuve d' Ascq Cedex (France); Benedetti, Marc F. [Institut de Physique du Globe de Paris, Sorbonne Paris Cité, Université Paris Diderot, UMR 7154, CNRS, F-75005 Paris (France); Pourret, Olivier [HydrISE, Institut Polytechnique LaSalle Beauvais, FR-60000 Beauvais (France); Conreux, Alexandra; Calandra, Ivan; Martinet, Blandine; Morvan, Xavier; Gommeaux, Maxime; Marin, Béatrice [GEGENAA, EA 3795, Université de Reims Champagne-Ardenne, SFR Condorcet FR CNRS 3417, 2 esplanade Roland Garros, 51100 Reims (France)

2016-10-15

Smelting activities are one of the most common sources of trace elements in the environment. The aim of this study was to determine the lead distribution in upper horizons (0–5 and 5–10 cm) of acidic soils in the vicinity of a lead-acid battery recycling plant in northern France. The combination of chemical methods (sequential extractions), physical methods (Raman microspectroscopy and scanning electron microscopy with an energy dispersive spectrometer) and multi-surface complexation modelling enabled an assessment of the behaviour of Pb. Regardless of the studied soil, none of the Pb-bearing phases commonly identified in similarly polluted environments (e.g., anglesite) were observed. Lead was mainly associated with organic matter and manganese oxides. The association of Pb with these soil constituents can be interpreted as evidence of Pb redistribution in the studied soils following smelter particle deposition. - Highlights: • Lead behavior was studied in smelter impacted soils. • A combination of experimental methods and modelling was employed. • Pb was mainly associated with organic matter and to a lesser degree with Mn oxides. • Pb was redistributed in soils after smelter particle deposition.
Lead distribution in soils impacted by a secondary lead smelter: Experimental and modelling approaches

International Nuclear Information System (INIS)

Schneider, Arnaud R.; Cancès, Benjamin; Ponthieu, Marie; Sobanska, Sophie; Benedetti, Marc F.; Pourret, Olivier; Conreux, Alexandra; Calandra, Ivan; Martinet, Blandine; Morvan, Xavier; Gommeaux, Maxime; Marin, Béatrice

2016-01-01

Smelting activities are one of the most common sources of trace elements in the environment. The aim of this study was to determine the lead distribution in upper horizons (0–5 and 5–10 cm) of acidic soils in the vicinity of a lead-acid battery recycling plant in northern France. The combination of chemical methods (sequential extractions), physical methods (Raman microspectroscopy and scanning electron microscopy with an energy dispersive spectrometer) and multi-surface complexation modelling enabled an assessment of the behaviour of Pb. Regardless of the studied soil, none of the Pb-bearing phases commonly identified in similarly polluted environments (e.g., anglesite) were observed. Lead was mainly associated with organic matter and manganese oxides. The association of Pb with these soil constituents can be interpreted as evidence of Pb redistribution in the studied soils following smelter particle deposition. - Highlights: • Lead behavior was studied in smelter impacted soils. • A combination of experimental methods and modelling was employed. • Pb was mainly associated with organic matter and to a lesser degree with Mn oxides. • Pb was redistributed in soils after smelter particle deposition.
Biological characterization of lead-enhanced exopolysaccharide produced by a lead resistant Enterobacter cloacae strain P2B.

Science.gov (United States)

Naik, Milind Mohan; Pandey, Anju; Dubey, Santosh Kumar

2012-09-01

A lead resistant bacterial strain isolated from effluent of lead battery manufacturing company of Goa, India has been identified as Enterobacter cloacae strain P2B based on morphological, biochemical characters, FAME profile and 16S rDNA sequence data. This bacterial strain could resist lead nitrate up to 1.6 mM. Significant increase in exopolysaccharide (EPS) production was observed as the production increased from 28 to 108 mg/L dry weight when exposed to 1.6 mM lead nitrate in Tris buffered minimal medium. Fourier-transformed infrared spectroscopy of this EPS revealed presence of several functional groups involved in metal binding viz. carboxyl, hydroxyl and amide groups along with glucuronic acid. Gas chromatography coupled with mass spectrometry analysis of alditol-acetate derivatives of acid hydrolysed EPS produced in presence of 1.6 mM lead nitrate demonstrated presence of several neutral sugars such as rhamnose, arabinose, xylose, mannose, galactose and glucose, which contribute to lead binding hydroxyl groups. Scanning electron microscope coupled with energy dispersive X-ray spectrometric analysis of this lead resistant strain exposed to 1.6 mM lead nitrate interestingly revealed mucous EPS surrounding bacterial cells which sequestered 17 % lead (as weight %) extracellularly and protected the bacterial cells from toxic effects of lead. This lead resistant strain also showed multidrug resistance. Thus these results significantly contribute to better understanding of structure, function and environmental application of lead-enhanced EPSs produced by bacteria. This lead-enhanced biopolymer can play a very important role in bioremediation of several heavy metals including lead.

Gastric acid reduction leads to an alteration in lower intestinal microflora

Energy Technology Data Exchange (ETDEWEB)

Kanno, Takayuki [Department of Gastroenterology, Wakayama Medical University, 811-1 Kimiidera, Wakayama-city, Wakayama 641-0012 (Japan); Matsuki, Takahiro [Yakult Central Institute for Microbiological Research, Tokyo (Japan); Oka, Masashi; Utsunomiya, Hirotoshi [Department of Gastroenterology, Wakayama Medical University, 811-1 Kimiidera, Wakayama-city, Wakayama 641-0012 (Japan); Inada, Kenichi [First Department of Pathology, Fujita Health University School of Medicine, Aichi (Japan); Magari, Hirohito; Inoue, Izumi; Maekita, Takao; Ueda, Kazuki; Enomoto, Shotaro; Iguchi, Mikitaka; Yanaoka, Kimihiko; Tamai, Hideyuki [Department of Gastroenterology, Wakayama Medical University, 811-1 Kimiidera, Wakayama-city, Wakayama 641-0012 (Japan); Akimoto, Shigeru [Department of Microbiology, Wakayama Medical University, 811-1 Kimiidera, Wakayama-city, Wakayama 641-0012 (Japan); Nomoto, Koji; Tanaka, Ryuichiro [Yakult Central Institute for Microbiological Research, Tokyo (Japan); Ichinose, Masao, E-mail: ichinose@wakayama-med.ac.jp [Department of Gastroenterology, Wakayama Medical University, 811-1 Kimiidera, Wakayama-city, Wakayama 641-0012 (Japan)

2009-04-17

To clarify the alterations in lower intestinal microflora induced by gastric acid reduction, the dynamics of 12 major genera or groups of bacteria comprising the microflora in feces and colonic contents were examined by quantitative real-time PCR in proton pump inhibitor-treated rats and in asymptomatic human subjects with hypochlorhydria. In both rat and human experiments, most genera or groups of intestinal microflora (facultative and obligate anaerobes) proliferated by gastric acid reduction, and marked and significant increases in the Lactobacilli group and Veillonella, oropharyngeal bacteria, were observed. In rats, potent gastric acid inhibition led to a marked and significant increase of intestinal bacteria, including the Bacteroidesfragilis group, while Bifidobacterium, a beneficial bacterial species, remained at a constant level. These results strongly indicate that the gastric acid barrier not only controls the colonization and growth of oropharyngeal bacteria, but also regulates the population and composition of lower intestinal microflora.
Gastric acid reduction leads to an alteration in lower intestinal microflora

International Nuclear Information System (INIS)

Kanno, Takayuki; Matsuki, Takahiro; Oka, Masashi; Utsunomiya, Hirotoshi; Inada, Kenichi; Magari, Hirohito; Inoue, Izumi; Maekita, Takao; Ueda, Kazuki; Enomoto, Shotaro; Iguchi, Mikitaka; Yanaoka, Kimihiko; Tamai, Hideyuki; Akimoto, Shigeru; Nomoto, Koji; Tanaka, Ryuichiro; Ichinose, Masao

2009-01-01

To clarify the alterations in lower intestinal microflora induced by gastric acid reduction, the dynamics of 12 major genera or groups of bacteria comprising the microflora in feces and colonic contents were examined by quantitative real-time PCR in proton pump inhibitor-treated rats and in asymptomatic human subjects with hypochlorhydria. In both rat and human experiments, most genera or groups of intestinal microflora (facultative and obligate anaerobes) proliferated by gastric acid reduction, and marked and significant increases in the Lactobacilli group and Veillonella, oropharyngeal bacteria, were observed. In rats, potent gastric acid inhibition led to a marked and significant increase of intestinal bacteria, including the Bacteroidesfragilis group, while Bifidobacterium, a beneficial bacterial species, remained at a constant level. These results strongly indicate that the gastric acid barrier not only controls the colonization and growth of oropharyngeal bacteria, but also regulates the population and composition of lower intestinal microflora.
Evaluation of erythrocyte delta-amino levulinic acid dehydratase activity as a short-term indicator in fish of a harmful exposure to lead

Energy Technology Data Exchange (ETDEWEB)

Hodson, P.V.; Blunt, B.R.; Spry, D.J.; Austen, K.

1977-04-01

The activity of erythrocyte delta-amino levulinic acid dehydratase (ALA-D) of fish is easily measured under a variety of experimental conditions. Exposure of rainbow trout (Salmo gairdneri), brook trout (Salvelinus fontinalis), goldfish (Carassius auratus), and pumpkinseeds (Lepomis gibbosus) to lead consistently inhibited ALA-D within 2 wks at concentrations as low as 10, 90, 470, and 90 ..mu..g/l, respectively. In rainbow and brook trout these concentrations were closely related to the published minimum effective concentrations causing sublethal harm. There was a significant linear relationship between ALA-D activity and log of blood lead concentration, between ALA-D activity and log of lead in water, and between blood lead and lead in water. Near lethal exposures to cadmium, copper, zinc, and mercury did not significantly inhibit ALA-D activity. Recovery of ALA-D activity of rainbow trout after transfer from 120 ..mu..g/l lead to clean water occurred in 8 wk. This enzyme provides fast, consistent, specific, and sensitive estimates of lead concentrations causing sublethal harm to fish and may help to relate sources of lead to degree of exposure of fish populations in the field.
Identification of lead acid battery parameters using kalman filtering in photovoltaic system

International Nuclear Information System (INIS)

Boutte, Aissa

2006-01-01

The conventional methods of battery identification parameters consist in estimating the state of charge (SOC), and in establishing a command adapted to charge or to discharge the battery, based on electrical model developed with fixed parameters, These methods are inefficient. The causes of this ineffectiveness are different: In the first place model does not adapt itself with the battery (fixed parameters, lack of modulated parameters, a big non-linearity ...).Secondly, the impossibility for the developed algorithms, to adapt itself with the change of the battery's parameters. New models of identification are used by combining the conventional methods with adaptive and dynamic techniques. They already used in other domains where they have proved a good efficiency and a robustness. Taking into consideration the problems mentioned, and trying to resolve them, we have chosen among the various methods of estimation, Kalman filter (KF) known for its efficiency, in the field of tracking parameters. In this work we try tp represent new ideas, to identify battery parameters using KF method and make an experimental analysis of the performance of this method by using Lead Acid Battery, which is a part of a photovoltaic system (PV).(Author)
Activation of the Glutamic Acid-Dependent Acid Resistance System in Escherichia coli BL21(DE3) Leads to Increase of the Fatty Acid Biotransformation Activity.

Science.gov (United States)

Woo, Ji-Min; Kim, Ji-Won; Song, Ji-Won; Blank, Lars M; Park, Jin-Byung

The biosynthesis of carboxylic acids including fatty acids from biomass is central in envisaged biorefinery concepts. The productivities are often, however, low due to product toxicity that hamper whole-cell biocatalyst performance. Here, we have investigated factors that influence the tolerance of Escherichia coli to medium chain carboxylic acid (i.e., n-heptanoic acid)-induced stress. The metabolic and genomic responses of E. coli BL21(DE3) and MG1655 grown in the presence of n-heptanoic acid indicated that the GadA/B-based glutamic acid-dependent acid resistance (GDAR) system might be critical for cellular tolerance. The GDAR system, which is responsible for scavenging intracellular protons by catalyzing decarboxylation of glutamic acid, was inactive in E. coli BL21(DE3). Activation of the GDAR system in this strain by overexpressing the rcsB and dsrA genes, of which the gene products are involved in the activation of GadE and RpoS, respectively, resulted in acid tolerance not only to HCl but also to n-heptanoic acid. Furthermore, activation of the GDAR system allowed the recombinant E. coli BL21(DE3) expressing the alcohol dehydrogenase of Micrococcus luteus and the Baeyer-Villiger monooxygenase of Pseudomonas putida to reach 60% greater product concentration in the biotransformation of ricinoleic acid (i.e., 12-hydroxyoctadec-9-enoic acid (1)) into n-heptanoic acid (5) and 11-hydroxyundec-9-enoic acid (4). This study may contribute to engineering E. coli-based biocatalysts for the production of carboxylic acids from renewable biomass.
Activation of the Glutamic Acid-Dependent Acid Resistance System in Escherichia coli BL21(DE3 Leads to Increase of the Fatty Acid Biotransformation Activity.

Directory of Open Access Journals (Sweden)

Ji-Min Woo

Full Text Available The biosynthesis of carboxylic acids including fatty acids from biomass is central in envisaged biorefinery concepts. The productivities are often, however, low due to product toxicity that hamper whole-cell biocatalyst performance. Here, we have investigated factors that influence the tolerance of Escherichia coli to medium chain carboxylic acid (i.e., n-heptanoic acid-induced stress. The metabolic and genomic responses of E. coli BL21(DE3 and MG1655 grown in the presence of n-heptanoic acid indicated that the GadA/B-based glutamic acid-dependent acid resistance (GDAR system might be critical for cellular tolerance. The GDAR system, which is responsible for scavenging intracellular protons by catalyzing decarboxylation of glutamic acid, was inactive in E. coli BL21(DE3. Activation of the GDAR system in this strain by overexpressing the rcsB and dsrA genes, of which the gene products are involved in the activation of GadE and RpoS, respectively, resulted in acid tolerance not only to HCl but also to n-heptanoic acid. Furthermore, activation of the GDAR system allowed the recombinant E. coli BL21(DE3 expressing the alcohol dehydrogenase of Micrococcus luteus and the Baeyer-Villiger monooxygenase of Pseudomonas putida to reach 60% greater product concentration in the biotransformation of ricinoleic acid (i.e., 12-hydroxyoctadec-9-enoic acid (1 into n-heptanoic acid (5 and 11-hydroxyundec-9-enoic acid (4. This study may contribute to engineering E. coli-based biocatalysts for the production of carboxylic acids from renewable biomass.
Comprehensive analysis of 5-aminolevulinic acid dehydrogenase (ALAD variants and renal cell carcinoma risk among individuals exposed to lead.

Directory of Open Access Journals (Sweden)

Dana M van Bemmel

Full Text Available BACKGROUND: Epidemiologic studies are reporting associations between lead exposure and human cancers. A polymorphism in the 5-aminolevulinic acid dehydratase (ALAD gene affects lead toxicokinetics and may modify the adverse effects of lead. METHODS: The objective of this study was to evaluate single-nucleotide polymorphisms (SNPs tagging the ALAD region among renal cancer cases and controls to determine whether genetic variation alters the relationship between lead and renal cancer. Occupational exposure to lead and risk of cancer was examined in a case-control study of renal cell carcinoma (RCC. Comprehensive analysis of variation across the ALAD gene was assessed using a tagging SNP approach among 987 cases and 1298 controls. Occupational lead exposure was estimated using questionnaire-based exposure assessment and expert review. Odds ratios (OR and 95% confidence intervals (CI were calculated using logistic regression. RESULTS: The adjusted risk associated with the ALAD variant rs8177796(CT/TT was increased (OR = 1.35, 95%CI = 1.05-1.73, p-value = 0.02 when compared to the major allele, regardless of lead exposure. Joint effects of lead and ALAD rs2761016 suggest an increased RCC risk for the homozygous wild-type and heterozygous alleles ((GGOR = 2.68, 95%CI = 1.17-6.12, p = 0.01; (GAOR = 1.79, 95%CI = 1.06-3.04 with an interaction approaching significance (p(int = 0.06. No significant modification in RCC risk was observed for the functional variant rs1800435(K68N. Haplotype analysis identified a region associated with risk supporting tagging SNP results. CONCLUSION: A common genetic variation in ALAD may alter the risk of RCC overall, and among individuals occupationally exposed to lead. Further work in larger exposed populations is warranted to determine if ALAD modifies RCC risk associated with lead exposure.
Iodide-assisted total lead measurement and determination of different lead fractions in drinking water samples.

Science.gov (United States)

Zhang, Yuanyuan; Ng, Ding-Quan; Lin, Yi-Pin

2012-07-01

Lead and its compounds are toxic and can harm human health, especially the intelligence development in children. Accurate measurement of total lead present in drinking water is crucial in determining the extent of lead contamination and human exposure due to drinking water consumption. The USEPA method for total lead measurement (no. 200.8) is often used to analyze lead levels in drinking water. However, in the presence of high concentration of the tetravalent lead corrosion product PbO(2), the USEPA method was not able to fully recover particulate lead due to incomplete dissolution of PbO(2) particles during strong acid digestion. In this study, a new procedure that integrates membrane separation, iodometric PbO(2) measurement, strong acid digestion and ICP-MS measurement was proposed and evaluated for accurate total lead measurement and quantification of different lead fractions including soluble Pb(2+), particulate Pb(II) carbonate and PbO(2) in drinking water samples. The proposed procedure was evaluated using drinking water reconstituted with spiked Pb(2+), spiked particulate Pb(II) carbonate and in situ formed or spiked PbO(2). Recovery tests showed that the proposed procedure and the USEPA method can achieve 93-112% and 86-103% recoveries respectively for samples containing low PbO(2) concentrations (0.018-0.076 mg Pb per L). For samples containing higher concentrations of PbO(2) (0.089-1.316 mg Pb per L), the USEPA method failed to meet the recovery requirement for total lead (85-115%) while the proposed method can achieve satisfactory recoveries (91-111%) and differentiate the soluble Pb(2+), particulate Pb(II) carbonate and PbO(2).
Comparative study for "36 V" vehicle applications: advantages of lead-acid batteries

Science.gov (United States)

Lailler, Patrick; Sarrau, Jean-François; Sarrazin, Christian

From thermal engine equipped vehicles to completely electric ones, evolution of light weight vehicles in the future will take several steps in so far as there is no adequate battery or fuel cell presently available to power these vehicles for "on the road" driving. On the other hand, for city driving, vehicles can be improved a lot in terms of fuel efficiency as well as air pollution, if partly or totally electric propulsion can be developed, manufactured and marketed for appropriate applications. The 36-42 V battery is part of this orientation towards improving the efficiency of thermal vehicles in city driving, while keeping adequate autonomy on the roads. Actually, in city traffic, thermal engines are idle most of the time and stop periods represent a large part of the time spent "driving", using up fuel and polluting air for no use at all. The idea of stopping the engine during these periods, if appropriately managed, might potentially lead to a large improvement in fuel economy as well as air pollution reduction. The association of a higher voltage battery to an alternator-starter device in thermal vehicles, seems to be an interesting way towards that end. In this paper, we are presenting our results of a study we have just completed in relationship with RENAULT & VALEO, supported by the French Ministry of Industry, concerning a comparative evaluation of different automobile energy storage systems, and the definition of specifications as the final step of this study. The main conclusion is that lead-acid will still remain dominant in this role, since its operational cost versus efficiency is by far the lowest of every battery presently considered, more particularly in the less expensive car segments.
40 CFR 60.372 - Standards for lead.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 6 2010-07-01 2010-07-01 false Standards for lead. 60.372 Section 60...) STANDARDS OF PERFORMANCE FOR NEW STATIONARY SOURCES Standards of Performance for Lead-Acid Battery Manufacturing Plants § 60.372 Standards for lead. (a) On and after the date on which the performance test...
Description and drawing of a mini-plant to lead-acid batteries active material production; Descricao e desenho de uma mini-planta piloto para producao de material ativo para baterias de chumbo-acido

Energy Technology Data Exchange (ETDEWEB)

D` Alkaine, C V; Mattos, J S.D.; Machado, D M; Nart, F C [Sao Carlos Univ., SP (Brazil). Dept. de Quimica

1985-12-31

As a part of the UFSCAR/Solar Energy/FINEP program, a pilot plant for the production of the active material for lead-acid batteries was developed. The basic operations are: milling and lead oxidation in ball mill, classifying of lead monoxide in the proper particle size by means of a cyclone, monoxide mixture with water and sulphuric acid, thus forming the paste. The paste is then placed on grids and finally scrapped and compacted. The plates pass through a 300 deg C oven and are cured in controlled atmosphere. (author). 4 refs
Lead poisoning in Australian fruit bats (Pteropus poliocephalus)

Energy Technology Data Exchange (ETDEWEB)

Zook, B.C.; Sauer, R.M.; Garner, F.M.

1970-09-01

Lead poisoning was diagnosed in 3 Australian fruit bats. Diagnoses were indicated by the finding of large acid-fast intranuclear inclusion bodies in renal and hepatic cells, and toxic amounts of lead in tissues. The source of lead was believed to be peeling leaded paint from the walls of the bats' cage.
Role of garlic extract and silymarin compared to dimercaptosuccinic acid (DMSA in treatment of lead induced nephropathy in adult male albino rats

Directory of Open Access Journals (Sweden)

Iman A. El-Khishin

2015-01-01

Full Text Available Lead poisoning has been known as an important disorder that affects individuals through acute, sub-acute and chronic exposure in environmental and occupational settings. This study was conducted to compare the curative role of garlic combined with silymarin versus dimercaptosuccinic acid (DMSA in decreasing lead induced nephrotoxicity in adult male albino rats. The period of lead intoxication extended for 3 months followed by either 1 month treatment with garlic and silymarin or 5 days treatment with DMSA. Lead poisoning caused non-significant difference in kidney function tests (BUN and serum creatinine while, it caused significant elevation in kidney lead level, significant decrease in renal antioxidant enzyme glutathione peroxidase and significant elevation in kidney malondialdehyde. Histologically, lead induced disorganization and shrinkage of glomeruli with sloughing and vaculation of epithelium, widening of Bowman's space and inflammatory infiltration in renal medulla. Treatment by garlic extract combined with silymarin as well as treatment with DMSA resulted in significant improvement in the affected parameters. Also, both methods of treatment resulted in improvement of the histopathological changes. It can be concluded that garlic extract combined to silymarin is comparable to DMSA in amelioration of lead induced nephrotoxicity.
Lead accumulation in the straw mushroom, Volvariella volvacea, from lead contaminated rice straw and stubble.

Science.gov (United States)

Kumhomkul, Thapakorn; Panich-pat, Thanawan

2013-08-01

Straw mushrooms were grown on lead contaminated rice straw and stubble. Study materials were dried, acid digested, and analyzed for lead using flame atomic absorption spectrophotometry. The results showed the highest lead concentration in substrate was 445.350 mg kg⁻¹ in Treatment 3 (T3) and the lowest was BD (below detection) in Treatment 1 (T1). The maximum lead content in straw mushrooms was 5.072 mg kg⁻¹ dw in pileus of T3 and the minimum lead content in straw mushrooms was BD in egg and mature (stalk and pileus) stage of T1. The lead concentration in straw mushrooms was affected by the age of the mycelium and the morphology of mushrooms. Mushrooms' lead uptake produced the highest accumulation in the cell wall. Some lead concentrations in straw mushrooms exceeded the EU standard (>3 mg kg⁻¹ dw).
Evaluation of Pb and Fe tenors present in the sediments nearby the activities of taking advantage of lead-acid batteries

International Nuclear Information System (INIS)

Soares, Fernanda; Andrade, Crescencio; Monteiro, Carlos; Oliveira, Daniela; Valentim, Eliane

2011-01-01

The region chosen for this study was the Municipality of Belo Jardim, Pernambuco State, Brazil, which is considered an important industrial complex of the production and repairing of lead-acid batteries. Sediment samples were collected near to the illegal smelting industries and analyzed by ionic exchange method using a alpha-beta proportional counter for determining the activity of Pb-210, radionuclide used as geochronological tool. The chemical elements Pb and Fe were determined by means of flame atomic absorption spectrometry. The obtained results indicated an expressive increasing of lead and iron concentrations in the last 20 years. The concentrations in the sampled profile varied from 318 to 15487 mg.kg-1 and from 19 to 1524 mg.kg-1 for Fe and Pb, respectively. (author)
Curing pasted plates for lead/acid batteries

Energy Technology Data Exchange (ETDEWEB)

Napoleon, E.S.

1987-02-15

This paper covers various aspects of the hydroset process and final drying of battery plates in a controlled chamber. Through the use of such chambers, battery makers are obtaining finished plates of consistent quality in 48 h or less, including final drying. Added benefits include: (i) reduced free-lead in plates; (ii) reduced floor space requirements; (iii) better knitting of paste to grid; (iv) reduced inventories; (v) reduced battery rejects.
Remediation of lead-contaminated water by geological fluorapatite and fungus Penicillium oxalicum.

Science.gov (United States)

Tian, Da; Wang, Wenchao; Su, Mu; Zheng, Junyi; Wu, Yuanyi; Wang, Shimei; Li, Zhen; Hu, Shuijin

2018-05-16

Phosphate-solubilizing fungi (PSF) can secrete large amounts of organic acids. In this study, the application of the fungus Penicillium oxalicum and geological fluorapatite (FAp) to lead immobilization was investigated. The formation and morphology of the lead-related minerals were analyzed by ATR-IR, XRD, Raman, and SEM. The quantity of organic acids secreted by P. oxalicum reached the maximum on the fourth day, which elevated soluble P concentrations from 0.4 to 108 mg/L in water. The secreted oxalic acid dominates the acidity in solution. P. oxalicum can survive in the solution with Pb concentration of ~ 1700 mg/L. In addition, it was shown that ~ 98% lead cations were removed while the fungus was cultured with Pb (~ 1700 mg/L) and FAp. The mechanism is that the released P from FAp (enhanced by organic acids) can react with Pb 2+ to form the stable pyromorphite mineral [Pb 5 (PO 4 ) 3 F]. The precipitation of lead oxalate also contributes to Pb immobilization. However, lead oxalate is more soluble due to its relatively high solubility. P. oxalicum has a higher rate of organic acid secretion compared with other typical PSF, e.g., Aspergillus niger. This study sheds light on bright future of applying P. oxalicum in Pb remediation.
On the reaction in the lead-acid battery (as the special review-article by the 2005' Gaston Planté Medal recipient)

Science.gov (United States)

Takehara, Zen-ichiro

It is my great pleasure to be awarded with the 2005' Gaston Planté Medal for significant contribution to the development of lead-acid battery science and technology. I would like to thank most heartily to Prof. D. Pavlov of Chairman, and all members of the Organic Committee of LABAT'2005 for the best treatment to select me as a 2005' Gaston Planté Medallist.
Levels and source apportionment of children's lead exposure: could urinary lead be used to identify the levels and sources of children's lead pollution?

Science.gov (United States)

Cao, Suzhen; Duan, Xiaoli; Zhao, Xiuge; Wang, Beibei; Ma, Jin; Fan, Delong; Sun, Chengye; He, Bin; Wei, Fusheng; Jiang, Guibin

2015-04-01

As a highly toxic heavy metal, the pollution and exposure risks of lead are of widespread concern for human health. However, the collection of blood samples for use as an indicator of lead pollution is not always feasible in most cohort or longitudinal studies, especially those involving children health. To evaluate the potential use of urinary lead as an indicator of exposure levels and source apportionment, accompanying with environmental media samples, lead concentrations and isotopic measurements (expressed as (207)Pb/(206)Pb, (208)Pb/(206)Pb and (204)Pb/(206)Pb) were investigated and compared between blood and urine from children living in the vicinities of a typical coking plant and lead-acid battery factory. The results showed urinary lead might not be a preferable proxy for estimating blood lead levels. Fortunately, urinary lead isotopic measurements could be used as an alternative for identifying the sources of children's lead exposure, which coincided well with the blood lead isotope ratio analysis. Copyright © 2015 Elsevier Ltd. All rights reserved.
Corrosion Behaviour of Sn-based Lead-Free Solders in Acidic Solution

Science.gov (United States)

Nordarina, J.; Mohd, H. Z.; Ahmad, A. M.; Muhammad, F. M. N.

2018-03-01

The corrosion properties of Sn-9(5Al-Zn), Sn-Cu and SAC305 were studied via potentiodynamic polarization method in an acidic solution of 1 M hydrochloric acid (HCl). Sn-9(5Al-Zn) produced different polarization profile compared with Sn-Cu and SAC305. The morphological analysis showed that small, deep grooves shaped of corrosion product formed on top of Sn-9(5Al-Zn) solder while two distinctive structures of closely packed and loosely packed corrosion product formed on top of Sn-Cu and SAC305 solder alloys. Phase analysis revealed the formations of various corrosion products such as SnO and SnO2 mainly dominant on surface of solder alloys after potentiodynamic polarization in 1 M hydrochloric acid (HCl).

Differential changes in serum uric acid concentrations in sibutramine promoted weight loss in diabetes: results from four weeks of the lead-in period of the SCOUT trial

DEFF Research Database (Denmark)

Andersson, Charlotte; Weeke, Peter; Brendorp, Bente

2009-01-01

ABSTRACT: BACKGROUND AND AIMS: Elevated levels of serum uric acid are associated with an increased risk of cardiovascular morbidity and mortality. The response of uric acid to weight loss therapy (lifestyle plus sibutramine) in an overweight and obese cardiovascular high risk population was studied....... METHODS AND RESULTS: Data from a four week single-blind lead-in period of the Sibutramine Cardiovascular OUTcomes (SCOUT) study were analyzed. 2584 patients (24%) had diabetes mellitus (DM) only, 1748 (16%) had cardiovascular disease (CVD) only and 6397 (60%) had both DM + CVD. Uric acid concentrations...... significantly more in patients without DM (p sibutramine induced lower uric acid levels...
Association of blood lead and mercury with estimated GFR in herbalists after the ban of herbs containing aristolochic acids in Taiwan.

Science.gov (United States)

Lin, Hsing-Hua; Chou, Shan-An; Yang, Hsiao-Yu; Hwang, Yaw-Huei; Kuo, Ching-Hua; Kao, Tze-Wah; Lo, Tsai-Chang; Chen, Pau-Chung

2013-08-01

This study was undertaken to explore the association of estimated glomerular filtration rate (GFR) with exposure to aristolochic acids (ALAs) and nephrotoxic metals in herbalists after the ban of herbs containing ALAs in Taiwan. This cross-sectional study recruited a total of 138 herbalists without end-stage renal disease or urothelial carcinoma from the Occupational Union of Chinese Herbalists in Taiwan in 2007. Aristolochic acid I (ALA-I) was measured by ultra-high-pressure liquid chromatography/ tandem mass spectrometry (UHPLC-MS/MS) and heavy metals in blood samples were analysed by Agilent 7500C inductively coupled plasma-mass spectrometry. Renal function was assessed by using a simplified Modification of Diet in Renal Disease Study equation to estimate GFR. Blood lead was higher in herbal dispensing procedures (p=0.053) and in subjects who self-prescribe herbal medicine (p=0.057); mercury was also higher in subjects living in the workplace (p=0.03). Lower estimated GFR was significantly associated with lead (β=-10.66, 95% CI -18.7 to -2.6) and mercury (β=-12.52, 95% CI -24.3 to -0.8) with a significant interaction (p=0.01) between mercury and lead; however, estimated GFR was not significantly associated with high ALA-I level groups, arsenic and cadmium after adjusting for other confounding factors. We found that lower estimated GFR was associated with blood lead and mercury in herbalists after the ban of herbs containing ALAs in Taiwan. The ALA-I exposure did not show a significant negative association of estimated GFR, which might due to herbalists having known how to distinguish ALA herbs after the banning policy. Rigorous monitoring is still needed to protect herbalists and the general population who take herbs.
Biomarker responses of Peromyscus leucopus exposed to lead and cadmium in the Southeast Missouri Lead Mining District.

Science.gov (United States)

Beyer, W Nelson; Casteel, Stan W; Friedrichs, Kristen R; Gramlich, Eric; Houseright, Ruth A; Nichols, John R; Karouna-Renier, Natalie K; Kim, Dae Young; Rangen, Kathleen L; Rattner, Barnett A; Schultz, Sandra L

2018-01-29

Biomarker responses and histopathological lesions have been documented in laboratory mammals exposed to elevated concentrations of lead and cadmium. The exposure of white-footed mice (Peromyscus leucopus) to these metals and the potential associated toxic effects were examined at three contaminated sites in the Southeast Missouri Lead Mining District and at a reference site in MO, USA. Mice from the contaminated sites showed evidence of oxidative stress and reduced activity of red blood cell δ-aminolevulinic acid dehydratase (ALAD). Histological examinations of the liver and kidney, cytologic examination of blood smears, and biomarkers of lipid peroxidation and DNA damage failed to show indications of toxic effects from lead. The biomagnification factor of cadmium (hepatic concentration/soil concentration) at a site with a strongly acid soil was 44 times the average of the biomagnification factors at two sites with slightly alkaline soils. The elevated concentrations of cadmium in the mice did not cause observable toxicity, but were associated with about a 50% decrease in expected tissue lead concentrations and greater ALAD activity compared to the activity at the reference site. Lead was associated with a decrease in concentrations of hepatic glutathione and thiols, whereas cadmium was associated with an increase. In addition, to support risk assessment efforts, we developed linear regression models relating both tissue lead dosages (based on a previously published a laboratory study) and tissue lead concentrations in Peromyscus to soil lead concentrations.
Biomarker responses of Peromyscus leucopus exposed to lead and cadmium in the Southeast Missouri Lead Mining District

Science.gov (United States)

Beyer, W. Nelson; Casteel, Stan W.; Friedrichs, Kristen R.; Gramlich, Eric; Houseright, Ruth A.; Nichols, John W.; Karouna-Renier, Natalie; Kim, Dae Young; Rangen, Kathleen; Rattner, Barnett A.; Schultz, Sandra

2018-01-01

Biomarker responses and histopathological lesions have been documented in laboratory mammals exposed to elevated concentrations of lead and cadmium. The exposure of white-footed mice (Peromyscus leucopus) to these metals and the potential associated toxic effects were examined at three contaminated sites in the Southeast Missouri Lead Mining District and at a reference site in MO, USA. Mice from the contaminated sites showed evidence of oxidative stress and reduced activity of red blood cell δ-aminolevulinic acid dehydratase (ALAD). Histological examinations of the liver and kidney, cytologic examination of blood smears, and biomarkers of lipid peroxidation and DNA damage failed to show indications of toxic effects from lead. The biomagnification factor of cadmium (hepatic concentration/soil concentration) at a site with a strongly acid soil was 44 times the average of the biomagnification factors at two sites with slightly alkaline soils. The elevated concentrations of cadmium in the mice did not cause observable toxicity, but were associated with about a 50% decrease in expected tissue lead concentrations and greater ALAD activity compared to the activity at the reference site. Lead was associated with a decrease in concentrations of hepatic glutathione and thiols, whereas cadmium was associated with an increase. In addition, to support risk assessment efforts, we developed linear regression models relating both tissue lead dosages (based on a previously published a laboratory study) and tissue lead concentrations in Peromyscus to soil lead concentrations.
Secondary lead production

Energy Technology Data Exchange (ETDEWEB)

Hollis, R.G.

1990-10-16

This invention is concerned with the efficient recovery of soft lead from the paste component of used automobile lead-acid storage batteries. According to the invention, a scrap which contains lead oxide, lead sulfate, and antimony in an oxidized state is processed in the following steps to recover lead. A refractory lined reaction vessel is continuously charged with the scrap, along with a reductant effective for reducing lead oxide. The charged material is melted and agitated by means of a submerged lance at 900-1150{degree}C whereby some of the lead oxide of the scrap is reduced to form molten lead. A slag layer is then formed above the molten lead, and an amount of lead oxide is maintained in the slag layer. The molten lead, now containing under 0.5 wt % of antimony, is removed, and the antimony oxide in the scrap is concentrated as oxide in the slag layer. Preferred embodiments of the invention result in the production, in a single step, of a soft lead substantially free of antimony. The slag may be subsequently treated to reduce the antimony oxide and produce a valuable antimony-lead product. Further advantages of the process are that a wet battery paste may be used as the feed without prior drying, and the process can be conducted at a temperature 100-150{degree}C lower than in previously known methods. In addition, a smaller reactor can be employed which reduces both capital cost and fuel costs. The process of the invention is illustrated by descriptions of pilot plant tests. 1 fig.
Research, development, and demonstration of lead-acid batteries for electric vehicle propulsion. Annual report for 1980

Energy Technology Data Exchange (ETDEWEB)

1981-03-01

Work performed during Oct. 1, 1979 to Sept. 30, 1980 for the development of lead-acid batteries for electric vehicle propulsion is described. During this report period many of the results frpm Globe Battery's design, materials and process development programs became evident in the achievement of the ISOA (Improved State of Art) specific energy, specific power, and energy efficiency goals while testing in progress also indicates that the cycle life goal can be met. These programs led to the establishment of a working pilot assembly line which produced the first twelve volt ISOA modules. Five of these modules were delivered to the National Battery Test Laboratory during the year for capacity, power and life testing, and assembly is in progress of three full battery systems for installation in vehicles. In the battery subsystem area, design of the acid circulation system for a ninety-six volt ISOA battery pack was completed and assembly of the first such system was initiated. Charger development has been slowed by problems encountered with reliability of some circuits but a prototype unit is being prepared which will meet the charging requirements of our ninety-six volt pack. This charger will be available during the 1981 fiscal year.
Liquid Membrane System for Extraction and Electrodeposition of Lead(II During Electrodialysis

Directory of Open Access Journals (Sweden)

Sadyrbaeva Tatiana

2017-05-01

Full Text Available A novel method for lead(II removal from aqueous acidic solutions is presented. The method involves electrodialysis through bulk liquid membranes accompanied by electrodeposition of metal from the cathodic solution. Solutions of di(2-ethylhexylphosphoric acid with admixtures of tri-n-octylamine in 1,2-dichloroethane were used as the liquid membranes. The effects of the main electrodialysis parameters as well as of the composition of the liquid membranes and aqueous solutions on the lead(II transport rate are studied. The optimal conditions are determined. A possibility of effective single-stage transfer of lead(II through the liquid membrane into dilute solutions of perchloric, nitric and acetic acids is demonstrated. Dense and adherent lead electrodeposits are obtained from perchloric acid solutions. Maximum extraction degree of 93 % and electrodeposition degree of ~60 % are obtained during 5 h of electrodialysis.
Lead-elevated activity of xanthine oxidase in lead-exposed workers

Directory of Open Access Journals (Sweden)

Sławomir Kasperczyk

2013-04-01

Full Text Available Background: The aim of the present study was to explore the connection between lead toxicity and the activity of xanthine oxidase (XO. In addition, we indicated the uric acid (UA and creatinine levels and concentration of erythrocyte malondialdehyde (MDA to estimate oxidative stress intensity. Materials and Methods: The examined group consisted of 125 healthy male employees of zinc and lead works. The examined group was divided into tertiles according to blood lead levels. In the collected blood samples, concentrations of lead-exposure indices, UA, creatinine, and MDA as well as activity of XO were measured concomitantly. The control group consisted of 32 healthy male administrative workers who were exposed to lead only environmentally. Results: XO activity and MDA level were significantly elevated in all tertiles compared to the control group. Creatinine level was significantly elevated in the medium and high tertiles. However, the level of UA was significantly elevated in the high tertile, while in the low and medium tertile only a tendency toward higher values was observed. Conclusions: Occupational exposure to lead induces activity of XO. This induction may contribute to the observed simultaneously increased oxidative stress, measured as MDA level, and the increased level of UA. Med Pr 2013;64(2:175–180
Study of transport of oxygen and water vapour between cells in valve regulated lead-acid batteries

Energy Technology Data Exchange (ETDEWEB)

Culpin, Barry [11 Bluebell Close, Whittle -le -Woods, Chorley PR6 7RH (United Kingdom); Peters, Ken [Battery Design and Manfg Systems, Glenbank, 77 Chatsworth Road, Worsley, Manchester M28 2GG (United Kingdom)

2006-08-25

Valve-regulated lead-acid batteries are maintenance free, safer, office compatible, and have higher volume efficiency than conventional designs. They are universally used in telecommunications and uninterruptible power supply systems. With the electrolyte immobilized in the separator or as a gel, it is feasible for a monobloc battery to have cells that are not fully sealed from one another, that is to have a common gas space, with certain attendant benefits. This study demonstrates that small differences in the saturation level, acid strength or operating temperature of the cells in such designs can initiate a cycle that may subsequently result in failure if the movement of oxygen and water vapour between cells is unrestricted. Cells that are initially out-of-balance will go further out-of-balance at an ever-increasing rate. This situation can also arise in monobloc designs with sealed cells if the intercell seal is inadequate or incomplete. Battery failure is associated with a re-distribution of water between the cells with some drying out and having high impedance. The preferential oxygen absorption in those cells produces heavily sulfated negative plates. Results on batteries tested under a range of overcharge conditions and temperatures are presented to illustrate these effects. The rate at which the cycle occurs depends on the initial relative density of the acid, the temperature or saturation imbalance between the cells, and the size of the interconnecting gas space. Batteries operating under a continuous cycling regime, particularly those with high overcharge currents and voltages that generate large volumes of oxygen, are more prone to this type of failure mode than batteries operating under low overcharge, intermittent cycling, or float conditions. (author)
Obtaining of barium sulfate from solution formed after desulfation of the active mass of scrap lead-acid batteries

Directory of Open Access Journals (Sweden)

O. A. Kalko

2014-03-01

Full Text Available Analyses of literature data about processes for solution utilization formed after desulfation of the active mass of scrap lead-acid batteries is performed. Optimal conditions for obtaining of barium sulfate sediment from ammonium sulfate solute and chemically pure Ba(OH2×8H2O и BaCl2×2H2O were found experimentally. In laboratory the commercial barium sulfate from sulfate solutions, that are waste of recycling process of battery scrap, with application of chloride and barium hydroxide was production. The possibility of using this product were discussed.
[Inhibition rate of gamma-aminolevulinic acid dehydratase activity in erythrocytes as a reliable index for individual workers of low lead exposure].

Science.gov (United States)

Hirano, H; Omichi, M; Ohishi, H; Ishikawa, K; Hirashima, N

1983-09-01

As the delta-aminolevulinic acid dehydratase (ALAD) activity in erythrocytes is decreased by lead exposure, we considered that a net reduction of ALAD activity by lead in blood should be the difference between the activity fully activated with zinc (Zn2+) and dithiothreitol (DTT) and that without activation. The optimal condition of activation of ALAD was found by addition of 0.25 mM of Zn2+ and 10 mM of DTT in the reaction mixture. Judging from our previous results that the amount of inhibition of ALAD activity can be represented as the rate of inhibition and is closely correlated with the dose of lead administered to rabbits, the inhibition rate of ALAD activity and lead content in blood (Pb-B) of lead workers were measured. The scatter diagram obtained from the inhibition rate and lead content in blood has two groups being divided at 50 micrograms/ml of Pb-B. In one group less than 50 micrograms/100 ml of Pb-B, the inhibition rate has been closely related to Pb-B., the regression equation being Y = 1.82 X + 11.7, and the correlation coefficient + 0.926. In another group more than 50 micrograms/100 ml of Pb-B the inhibition rate remained constant at the 90% level. Measurement of the inhibition rate suggests to have practical validity for monitoring lead exposure in workers, and by means of a nomograph lead content in blood can be estimated from the inhibition rate.
Development of an airborne lead analysis kit and its application.

Science.gov (United States)

Kongtip, Pornpimol; Borisut, Pornchulee; Yoosook, Witaya; Osiri, Pramuk; Rojanavipart, Piangchan

2010-11-01

We developed a method to analyze airborne lead concentrations in the field. It was a modification of the colorimetric method using the reaction between 4(2-pyridylazo)-resorcinol (PAR) and lead with cyanex302 in an acid medium to reduce interfering metals. The lead concentration was detected with a photometer made in Thailand. The developed method uses an impinger containing 1% nitric acid solution as an absorbing agent to collect airborne lead at a flow rate of less than or equal to one liter/minute. Cyanex302 solution in toluene was used to extract metals from the samples and 0.1M nitric acid was used to extract just lead. The lead solution was reacted in 0.5 ml of 0.03% PAR solution, with 1 ml ammonium chloride buffer; the absorption of this solution was measured by a photometer. The results show the limit of detection (LOD) was 0.01 mg/l. The limit of quantification (LOQ) was 0.03 mg/l. The percent recovery of the lead concentrations of 0.05 - 3.0 mg/l was 94.0 to 103.5%. The precision presented as %CV ranged from 0.65 to 10.27%. Lead concentration in a lead smelting factory detected by this method was not significantly different from that detected by the NIOSH method: 7,303 at a 95% confidence level.
RABL2 Is Required for Hepatic Fatty Acid Homeostasis and Its Dysfunction Leads to Steatosis and a Diabetes-Like State.

Science.gov (United States)

Yi Lo, Jennifer Chi; O'Connor, Anne E; Andrews, Zane B; Lo, Camden; Tiganis, Tony; Watt, Matthew J; O'Bryan, Moira K

2016-12-01

Fatty liver, or hepatic steatosis, is an alarmingly common pathology in western societies, in large part because if left unheeded, it can lead to life-threatening forms of nonalcoholic fatty liver disease, including nonalcoholic steatohepatitis, fibrosis, cirrhosis, and hepatocellular carcinoma. As such, it is essential that we attain a greater understanding of the pathways that control energy partitioning in the liver and ultimately how they are impacted by environmental factors. Here, we define the essential requirement for a member of the Ras-related protein in the brain (RAB)-like (RABL) clade of small GTPases, RABL2, in fatty acid metabolism including in microtubule-associated mitochondrial movement within the liver. RABL2 dysfunction, even in mice fed a low-fat chow diet, leads to retarded hepatic mitochondria movement associated with and a cascading phenotype of interrelated metabolic defects reminiscent of a type 2 diabetic state: hepatic steatosis, insulin resistance, glucose intolerance, and adult onset obesity. RABL2 dysfunction does not, however, alter mitochondrial content, or the inherent respiratory capacity of individual mitochondria per se. Rather, it is associated with a decreased capacity for fatty oxidation in the context of the intact cell, suggesting a complex, and important, role for mitochondrial movement in metabolic health. Our data highlight the importance of RABL2 and mitochondrial dynamics in hepatic fatty acid oxidation and in the achievement of metabolic balance.
Imported occupational lead poisoning: report of four cases.

Science.gov (United States)

Petracca, M; Scafa, F; Boeri, R; Flachi, Daniela; Candura, S M

2013-01-01

In most industrialized countries, occupational lead poisoning has become increasingly rare, however this metal remains a serious health hazard in the rest of the world. We observedfour male patients (aged 35 / 54 years) who had suffered recurrent abdominal pain due to recent lead exposure (for 7 to 13 months) in two Chinese battery recycling plants. On their return to Italy, three of them presented normocytic, normochromic anaemia. The diagnosis was confirmed by high lead levels in the blood and urine, decreased erythrocyte delta-aminolevulinic acid dehydratase (ALA-D), raised erythrocyte zinc protoporphyrin (ZP), and elevated urinary excretion of b-aminolevulinic acid (ALA-U) and porphyrins. Chelation with EDTA resulted in increased urinary lead excretion, improvement of the clinical picture, decreased ZP, and progressive normalization of the other lead biomarkers (Pb-B, ALA-D, ALA-U, urinary porphyrins). Temporary work in developing countries may result in imported lead poisoning. Differential diagnosis of this unusual condition requires careful medical history collection and specific toxicological analysis. Preventive measures for workers going abroad are needed.
Lifetime modelling of lead acid batteries

DEFF Research Database (Denmark)

Bindner, H.; Cronin, T.; Lundsager, P.

2005-01-01

The performance and lifetime of energy storage in batteries are an important part of many renewable based energy systems. Not only do batteries impact on the system performance but they are also a significant expenditure when considering the whole lifecycle costs. Poor prediction of lifetime can......, therefore, lead to uncertainty in the viability of the system in the long term. This report details the work undertaken to investigate and develop two different battery life prediction methodologies withspecific reference to their use in hybrid renewable energy systems. Alongside this, results from battery...... tests designed to exercise batteries in similar modes to those that they experience in hybrid systems have also been analysed. These have yieldedbattery specific parameters for use in the prediction software and the first results in the validation process of the software are also given. This work has...
Lead poisoning in dogs

International Nuclear Information System (INIS)

Zook, B.C.; Carpenter, J.L.; Leeds, E.B.

1969-01-01

Lead poisoning was diagnosed and studied in 60 dogs. It was found that lead poisoning is a common disease of young dogs, especially in the summer and fall, and is related to their chewing and eating habits resulting in the ingestion of paint, linoleum, or other lead-containing materials. The signs were characterized by gastrointestinal dysfunction (colic, vomiting, and diarrhea) and nervous disorders (convulsions, hysteria, nervousness, behavioral changes). The blood findings, which the authors consider nearly pathognomonic, consisted of numerous stippled and immature (especially nucleated) erythrocytes in the absence of severe anemia. Protein and casts were frequently found in the urine. Radiography sometimes revealed lead-containing particles in the gastro-intestinal tract, and lead lines were occasionally detected in the metaphysis of long bones in immature dogs. Treatment with calcium ethylenediamine-tetraacetic acid resulted in rapid and often dramatic recoveries in nearly all instances. Removal of lead from the gastrointestinal tract and treatment to relieve pronounced central nervous disorders was sometimes necessary. 40 references, 6 figures, 7 tables
Coordination chemistry of two heavy metals: I, Ligand preferences in lead(II) complexation, toward the development of therapeutic agents for lead poisoning: II, Plutonium solubility and speciation relevant to the environment

International Nuclear Information System (INIS)

Neu, M.P.

1993-11-01

The coordination chemistry and solution behavior of the toxic ions lead(II) and plutonium(IV, V, VI) have been investigated. The ligand pK a s and ligand-lead(II) stability constants of one hydroxamic acid and four thiohydroaxamic acids were determined. Solution thermodynamic results indicate that thiohydroxamic acids are more acidic and slightly better lead chelators than hydroxamates, e.g., N-methylthioaceto-hydroxamic acid, pK a = 5.94, logβ 120 = 10.92; acetohydroxamic acid, pK a = 9.34, logβ l20 = 9.52. The syntheses of lead complexes of two bulky hydroxamate ligands are presented. The X-ray crystal structures show the lead hydroxamates are di-bridged dimers with irregular five-coordinate geometry about the metal atom and a stereochemically active lone pair of electrons. Molecular orbital calculations of a lead hydroxamate and a highly symmetric pseudo octahedral lead complex were performed. The thermodynamic stability of plutonium(IV) complexes of the siderophore, desferrioxamine B (DFO), and two octadentate derivatives of DFO were investigated using competition spectrophotometric titrations. The stability constant measured for the plutonium(IV) complex of DFO-methylterephthalamide is logβ 110 = 41.7. The solubility limited speciation of 242 Pu as a function of time in near neutral carbonate solution was measured. Individual solutions of plutonium in a single oxidation state were added to individual solutions at pH = 6.0, T = 30.0, 1.93 mM dissolved carbonate, and sampled over intervals up to 150 days. Plutonium solubility was measured, and speciation was investigated using laser photoacoustic spectroscopy and chemical methods
Six years of operational experience with a lead acid battery in the autonomous PV-hydrogen plant phoebus Juelich

Energy Technology Data Exchange (ETDEWEB)

Meurer, C.; Brocke, W.A.; Emonts, B.; Heuts, G.; Mai, H.; Croe, D. [Forschungszentrum Juelich GmbH, Juelich (Germany). Inst. for Materials and Processes in Energy Systems IWV-3

1999-07-01

A set of 110 lead acid battery cells with a capacity of 1380 Ah was operated for six years in the PV-hydrogen plant PHOEBUS Juelich under realistic consumer and solar conditions. The plant is controlled by an energy management system that is specially designed for the use of a battery combined with a hydrogen long-term storage. The energy management system uses the state of charge SOC, which is determined by measurements of the battery current using validated models of the gassing current and the equilibrium voltage. It was found that after six years of operation there is hardly any fading of battery capacity. (orig.)
The problem of auto-discharge in lead-acid batteries; O problema da auto-descarga em baterias chumbo acido

Energy Technology Data Exchange (ETDEWEB)

Avaca, L A; Gonzalez, E R; Tremiliosi Filho, G; Silva, C.C. da; Maezuru, M [Sao Paulo Univ., Sao Carlos, SP (Brazil). Inst. de Fisica e Quimica

1985-12-31

Storage batteries used together with photovoltaic cells in remote locations must have special characteristics to fit the charge and discharge profiles to which they are submitted. Therefore, to avoid over dimensioning of the photovoltaic cells, the batteries must have particularly low self-discharge characteristics. The problem of self-discharge is directly connected to the degree of technological development in the fabrication of the batteries. The self-discharge of the SLI batteries made locally was measured under standardized conditions and the results were correlated with the kinetics of the electrochemical hydrogen evolution reaction on the lead alloys in acid medium. (author). 7 figs., 4 tabs., 11 refs
Linoleic acid metabolite leads to steroid resistant asthma features partially through NF-?B

OpenAIRE

Panda, Lipsa; Gheware, Atish; Rehman, Rakhshinda; Yadav, Manish K.; Jayaraj, B. S.; Madhunapantula, SubbaRao V.; Mahesh, Padukudru Anand; Ghosh, Balaram; Agrawal, Anurag; Mabalirajan, Ulaganathan

2017-01-01

Studies have highlighted the role of nutritional and metabolic modulators in asthma pathobiology. Steroid resistance is an important clinical problem in asthma but lacks good experimental models. Linoleic acid, a polyunsaturated fatty acid, has been linked to asthma and glucocorticoid sensitivity. Its 12/15?lipoxygenase metabolite, 13-S-hydroxyoctadecadienoic acid (HODE) induces mitochondrial dysfunction, with severe airway obstruction and neutrophilic airway inflammation. Here we show that H...

Mobilized plasma lead as an index of lead body burden and its relation to the heme-related indices.

Science.gov (United States)

Sakai, T; Ushio, K; Ikeya, Y

1998-07-01

Plasma lead (Pb-P) from workers were distributed in two main fractions: a protein bound fraction and low molecular weight fractions. Lead mobilized into plasma by CaEDTA was mainly observed in the low molecular weight fraction corresponding to lead disodium ethylenediamine tetraacetic acid (PbEDTA). The peak levels of Pb-P was attained around 1.5 and 2.5 hours after the start of CaEDTA injection. Pb-P and blood lead levels (Pb-B) at 2 h after the injection were 4.26 (+/- 2.84) and 0.96 (+/- 0.27) fold of the initial levels just before the injection. Pb-P concentrations at 2 hours after the start of CaEDTA injection (MPb-P) were well correlated (r = 0.740) with amounts of lead excreted in urine for 24 h thereafter (MPb-U). log MPb-P as well as log MPb-U were correlated with Pb-B (r = 0.765 and 0.817, respectively). Correlation coefficients of lead body burden (MPb-P or MPb-U) vs the logarithms of the effect indices (delta-aminolevulinic acid (ALA) dehydratase, ALA in urine, coproporphyrin in urine, and erythrocyte zinc protoporphyrin) were higher than the correlation coefficients of exposure indices (Pb-B or Pb-U) vs the logarithms of the effect indices. Thus the biological effect monitoring is significant and reliable for evaluating the functional components of lead body burden (MPb-P or MPb-U).
fractionation of lead-acid battery soil amended with biochar 36

African Journals Online (AJOL)

USER

Biochar has a high surface area, highly porous, variable – charge organic material that has the potential to ... Keywords: Biochar, Lead–acid Battery, Fractionation and Heavy metals. INTRODUCTION .... toxicity of heavy metal ions in the soils.
[Isolation, identification and lead adsorption study of lead-resistant Lactobacillus casei strains from feces of healthy newborns].

Science.gov (United States)

Shen, Wei; Yu, Qin-Fei; Wang, Yu-Hao; Zhang, Yi-Duo; Meng, Xiao-Jing; Fan, Hong-Ying

2016-12-20

To isolate and identify lead-resistant Lactobacillus casei strains with lead adsorption ability from the stool of healthy newborns as a new source of bacteria for developing lead-eliminating food products. MRS was used to isolate lead-resistant bacteria from the feces of 30 healthy and full-term neonates. A phylogenetic tree was constructed based on the morphological characteristics and 16S rRNA sequences of the isolated bacteria. Physiological and biochemical characterizations of the bacteria were performed according to the Berger's Systematic Bacteriology Handbook, followed by antimicrobial susceptibility test and acid-tolerant bile salt test. The adsorption capacity of Pb 2+ of the bacteria was determined by inductively coupled plasma-optical emission spectroscopy (ICP-OES). Three strains of Lactobacillus casei were isolated, which were resistant to penicillin and ceftriaxone and could tolerate the exposure to 500 mg/L Pb 2+ . Acid-tolerant bile salt test showed that the bacteria were resistant to culture in the presence of artificial gastric juice (pH 2.0) for 3 h, and their survival rate reached 62.5% following exposure to 0.3% bile salt for 8 h. The bacteria showed a Pb 2+ adsorption rate of 90.4% at a low Pb 2+ concentration (1 mg/L) and of 86.27% at a high Pb 2+ concentration (50 mg/L). Three Lactobacillus casei strains lead adsorption ability were isolated from the feces of newborns. These bacterial strains provide a new solution to alleviate lead poisoning by probiotic dietary.
Acids and bases solvent effects on acid-base strenght

CERN Document Server

Cox, Brian G

2013-01-01

Acids and bases are ubiquitous in chemistry. Our understanding of them, however, is dominated by their behaviour in water. Transfer to non-aqueous solvents leads to profound changes in acid-base strengths and to the rates and equilibria of many processes: for example, synthetic reactions involving acids, bases and nucleophiles; isolation of pharmaceutical actives through salt formation; formation of zwitter- ions in amino acids; and chromatographic separation of substrates. This book seeks to enhance our understanding of acids and bases by reviewing and analysing their behaviour in non-aqueous solvents. The behaviour is related where possible to that in water, but correlations and contrasts between solvents are also presented.
Coordination chemistry of two heavy metals: I, Ligand preferences in lead(II) complexation, toward the development of therapeutic agents for lead poisoning: II, Plutonium solubility and speciation relevant to the environment

Energy Technology Data Exchange (ETDEWEB)

Neu, Mary Patricia [Univ. of California, Berkeley, CA (United States)

1993-11-01

The coordination chemistry and solution behavior of the toxic ions lead(II) and plutonium(IV, V, VI) have been investigated. The ligand pK_as and ligand-lead(II) stability constants of one hydroxamic acid and four thiohydroaxamic acids were determined. Solution thermodynamic results indicate that thiohydroxamic acids are more acidic and slightly better lead chelators than hydroxamates, e.g., N-methylthioaceto-hydroxamic acid, pK_a = 5.94, logβ₁₂₀ = 10.92; acetohydroxamic acid, pK_a = 9.34, logβ₁₂₀ = 9.52. The syntheses of lead complexes of two bulky hydroxamate ligands are presented. The X-ray crystal structures show the lead hydroxamates are di-bridged dimers with irregular five-coordinate geometry about the metal atom and a stereochemically active lone pair of electrons. Molecular orbital calculations of a lead hydroxamate and a highly symmetric pseudo octahedral lead complex were performed. The thermodynamic stability of plutonium(IV) complexes of the siderophore, desferrioxamine B (DFO), and two octadentate derivatives of DFO were investigated using competition spectrophotometric titrations. The stability constant measured for the plutonium(IV) complex of DFO-methylterephthalamide is logβ₁₂₀ = 41.7. The solubility limited speciation of ²⁴²Pu as a function of time in near neutral carbonate solution was measured. Individual solutions of plutonium in a single oxidation state were added to individual solutions at pH = 6.0, T = 30.0, 1.93 mM dissolved carbonate, and sampled over intervals up to 150 days. Plutonium solubility was measured, and speciation was investigated using laser photoacoustic spectroscopy and chemical methods.
Hybrid unscented particle filter based state-of-charge determination for lead-acid batteries

International Nuclear Information System (INIS)

Shen, Yanqing

2014-01-01

Accurate prediction of cell SOC (state of charge) is important for the safety and functional capabilities of the battery energy storage application system. This paper presents a hybrid UPF (unscented particle filter) based SOC determination combined model for batteries. To simulate the entire dynamic electrical characteristics of batteries, a novel combined state space model, which takes current as a control input and let SOC and two constructed parameters as state variables, is advanced to represent cell behavior. Besides that, an improved UPF method is used to evaluate cell SOC. Taking lead-acid batteries for example, we apply the established model for test. Results show that the evolved combined state space cell model simulates battery dynamics robustly with high accuracy and the prediction value based on the improved UPF method converges to the real SOC very quickly within the error of±2%. - Highlights: • This paper introduces a hybrid UPF based SOC determination model for batteries. • The evolved model takes SOC and two constructed parameters as state variables. • The combined state space cell model simulates battery dynamics robustly. • NLMS based method is employed to lessen search space and fasten convergence process. • Novel model converges to the real SOC robustly and quickly with fewer particles
Effect of Glycine on Lead Mobilization, Lead-Induced Oxidative Stress, and Hepatic Toxicity in Rats

Directory of Open Access Journals (Sweden)

Yolanda Alcaraz-Contreras

2011-01-01

Full Text Available The effectiveness of glycine in treating experimental lead intoxication was examined in rats. Male Wistar rats were exposed to 3 g/L lead acetate in drinking water for 5 weeks and treated thereafter with glycine (100 and 500 mg/kg, orally once daily for 5 days or glycine (1000 mg/kg, orally once daily for 28 days. The effect of these treatments on parameters indicative of oxidative stress (glutathione and malondialdehyde levels, the activity of blood -aminolevulinic acid dehydratase, and lead concentration in blood, liver, kidney, brain, and bone were investigated. Liver samples were observed for histopathological changes. Glycine was found to be effective in (1 increasing glutathione levels; (2 reducing malondialdehyde levels; (3 decreasing lead levels in bone with the highest dose. However, glycine had no effect on lead mobilization when 100 and 500 mg/kg glycine were administered. In microscopic examination, glycine showed a protective effect against lead intoxication.
Selection of micronutrients used along with DMSA in the treatment of moderately lead intoxicated mice

Energy Technology Data Exchange (ETDEWEB)

Liao, Yingjun [China Medical University, Department of Physiology, School of Basic Medicine, Shenyang, Liaoning (China); Yu, Fei; Zhi, Xuping; An, Li; Yang, Jun [China Medical University, Department of Nutrition and Food Hygiene, School of Public Health, Shenyang, Liaoning (China); Jin, Yaping; Lu, Chunwei; Li, Gexin [China Medical University, Department of Environmental and Occupational Health, School of Public Health, Shenyang, Liaoning (China)

2008-01-15

The objective of this study was to explore the optimum combination of micronutrients used with 2,3-dimercaptosuccinic acid (DMSA) in the treatment of moderately lead-intoxicated mice. Experiment was carried out based on the orthogonal design L{sub 8}(2{sup 7}) setting six factors with two different levels of each, and eight groups of mice were needed. Mice were exposed to lead by drinking water contaminated with 0.1% lead acetate for four consecutive weeks, and then supplemented by gavage with different combinations of micronutrients with and without DMSA as designed in the orthogonal table. Lead levels in blood, liver, kidney, brain and bone and activities of blood {delta}-aminolevulinic acid dehydratase (ALAD) were analyzed after cessation of supplementation. The results suggested that DMSA was the only factor which could decrease significantly lead levels in blood, liver, kidney and bone; calcium and ascorbic acid were the notable factors decreasing lead levels in blood, liver, kidney, bone and brain; zinc and calcium were the notable factors reversing the lead-inhibited activities of blood ALAD; taurine was the notable factor decreasing lead levels in kidney and brain; and thiamine was the notable factor decreasing lead levels in brain. The lowest lead level in blood, liver, kidney and bone was shown in the mice supplemented with combination of calcium and ascorbic acid along with DMSA. In conclusion, the optimum combination of micronutrients used with DMSA suggested in present study was calcium and ascorbic acid, which seemed to potentiate the chelating efficacy of DMSA in the treatment of moderately lead intoxicated mice. (orig.)
Chelation therapy in intoxications with mercury, lead and copper

DEFF Research Database (Denmark)

Cao, yang; Skaug, Marit Aralt; Andersen, Ole

2015-01-01

In the present review we provide an update of the appropriate use of chelating agents in the treatment of intoxications with compounds of mercury, lead and copper. The relatively new chelators meso-2,3-dimercaptosuccinic acid (DMSA) and 2,3-dimercapto-propanesulphonate (DMPS) can effectively...... mobilize deposits of mercury as well as of lead into the urine. These drugs can be administered orally and have relatively low toxicity compared to the classical antidote dimercaptopropanol (BAL). d-Penicillamine has been widely used in copper overload, although 2,3-dimercaptosuccinic acid...
Effect of lead on nucleic acid and protein contents of rice (Oryza sativa L. ) seedlings and its interaction with IAA and GA/sub 3/ in different plant systems

Energy Technology Data Exchange (ETDEWEB)

Maitra, P.; Mukherh, S.

1979-09-01

Activity of lead acetate, (CH/sub 3/COO)/sub 2/Pb, 3 H/sub 2/O, was studied in germinating rice seedlings with respect to RNA, DNA and alkali soluble protein contents. RNA, DNA and protein contents greatly reduced both in embryo and endosperm with increasing concentrations of lead and with concomitant increase in amino acid content in embryo. When IAA was supplied in combination with lead acetate, variable amounts of relief of elongation inhibition of wheat coleoptile sections were noticed. With GA/sub 3/, however, lead-induced inhibition of either lettuce (Lactuca sativa L.) hypocotyl elongation or ..cap alpha..-amylase production in rice half seeds was largely overcome.
Lead-Binding Proteins: A Review

Directory of Open Access Journals (Sweden)

Harvey C. Gonick

2011-01-01

Full Text Available Lead-binding proteins are a series of low molecular weight proteins, analogous to metallothionein, which segregate lead in a nontoxic form in several organs (kidney, brain, lung, liver, erythrocyte. Whether the lead-binding proteins in every organ are identical or different remains to be determined. In the erythrocyte, delta-aminolevulinic acid dehydratase (ALAD isoforms have commanded the greatest attention as proteins and enzymes that are both inhibitable and inducible by lead. ALAD-2, although it binds lead to a greater degree than ALAD-1, appears to bind lead in a less toxic form. What may be of greater significance is that a low molecular weight lead-binding protein, approximately 10 kDa, appears in the erythrocyte once blood lead exceeds 39 μg/dL and eventually surpasses the lead-binding capacity of ALAD. In brain and kidney of environmentally exposed humans and animals, a cytoplasmic lead-binding protein has been identified as thymosin β4, a 5 kDa protein. In kidney, but not brain, another lead-binding protein has been identified as acyl-CoA binding protein, a 9 kDa protein. Each of these proteins, when coincubated with liver ALAD and titrated with lead, diminishes the inhibition of ALAD by lead, verifying their ability to segregate lead in a nontoxic form.
Sequential injection redox or acid-base titration for determination of ascorbic acid or acetic acid.

Science.gov (United States)

Lenghor, Narong; Jakmunee, Jaroon; Vilen, Michael; Sara, Rolf; Christian, Gary D; Grudpan, Kate

2002-12-06

Two sequential injection titration systems with spectrophotometric detection have been developed. The first system for determination of ascorbic acid was based on redox reaction between ascorbic acid and permanganate in an acidic medium and lead to a decrease in color intensity of permanganate, monitored at 525 nm. A linear dependence of peak area obtained with ascorbic acid concentration up to 1200 mg l(-1) was achieved. The relative standard deviation for 11 replicate determinations of 400 mg l(-1) ascorbic acid was 2.9%. The second system, for acetic acid determination, was based on acid-base titration of acetic acid with sodium hydroxide using phenolphthalein as an indicator. The decrease in color intensity of the indicator was proportional to the acid content. A linear calibration graph in the range of 2-8% w v(-1) of acetic acid with a relative standard deviation of 4.8% (5.0% w v(-1) acetic acid, n=11) was obtained. Sample throughputs of 60 h(-1) were achieved for both systems. The systems were successfully applied for the assays of ascorbic acid in vitamin C tablets and acetic acid content in vinegars, respectively.
Hydrogen generation comparison between lead-calcium and lead-antimony batteries in nuclear power plant

International Nuclear Information System (INIS)

Zhao Hongjun; Qi Suoni; Shen Yan; Li Jia

2014-01-01

Battery type selection is performed with the help of technical information supplied by vendors, and according to relevant criteria. Analysis and comparison of the hydrogen generation differences between two different lead-acid battery types are carried out through calculation. The analysis result may provide suggestions for battery type selection in nuclear power plant. (authors)
Photovoltaic High-Frequency Pulse Charger for Lead-Acid Battery under Maximum Power Point Tracking

Directory of Open Access Journals (Sweden)

Hung-I. Hsieh

2013-01-01

Full Text Available A photovoltaic pulse charger (PV-PC using high-frequency pulse train for charging lead-acid battery (LAB is proposed not only to explore the charging behavior with maximum power point tracking (MPPT but also to delay sulfating crystallization on the electrode pores of the LAB to prolong the battery life, which is achieved due to a brief pulse break between adjacent pulses that refreshes the discharging of LAB. Maximum energy transfer between the PV module and a boost current converter (BCC is modeled to maximize the charging energy for LAB under different solar insolation. A duty control, guided by a power-increment-aided incremental-conductance MPPT (PI-INC MPPT, is implemented to the BCC that operates at maximum power point (MPP against the random insolation. A 250 W PV-PC system for charging a four-in-series LAB (48 Vdc is examined. The charging behavior of the PV-PC system in comparison with that of CC-CV charger is studied. Four scenarios of charging statuses of PV-BC system under different solar insolation changes are investigated and compared with that using INC MPPT.
Investigation on batch biosorption of lead using Lactobacillius ...

African Journals Online (AJOL)

In this research, the biosorption of lead by Lactobacillus bulgaricus was investigated. The mechanism for the biosorption was similar to ionic exchanger. The media pH, weight of dried biomass and initial lead concentration were investigated at ambient temperature. At high acidic solution (pH<1.5) and also in alkaline ...
Case Report: Valproic Acid and Risperidone Treatment Leading to Development of Hyperammonemia and Mania

Science.gov (United States)

Carlson, Teri; Reynolds, Charles A.; Caplan, Rochelle

2007-01-01

This case report describes two children who developed hyperammonemia together with frank manic behavior during treatment with a combination of valproic acid and risperidone. One child had been maintained on valproic acid for years and risperidone was added. In the second case, valproic acid was introduced to a child who had been treated with…
Complete deficiency of mitochondrial trifunctional protein due to a novel mutation within the beta-subunit of the mitochondrial trifunctional protein gene leads to failure of long-chain fatty acid beta-oxidation with fatal outcome

NARCIS (Netherlands)

Schwab, Karl Otfried; Ensenauer, Regina; Matern, Dietrich; Uyanik, Gökhan; Schnieders, Birgit; Wanders, Ronald A.; Lehnert, Willy

2003-01-01

The mitochondrial trifunctional protein (MTP) is a multienzyme complex which catalyses three of the four chain-shortening reactions in the beta-oxidation of long-chain fatty acids. Clinically, failure of long-chain fatty acid beta-oxidation leads to hypoketotic hypoglycaemia associated with coma,
Measuring Vitamin C Content of Commercial Orange Juice Using a Pencil Lead Electrode

Science.gov (United States)

King, David; Friend, Jeffrey; Kariuki, James

2010-01-01

A pencil lead successfully served as an electrode for the determination of ascorbic acid in commercial orange juice. Cyclic voltammetry was used as an electrochemical probe to measure the current produced from the oxidation of ascorbic acid with a variety of electrodes. The data demonstrate that the less expensive pencil lead electrode gives…
ER Stress Inhibits Liver Fatty Acid Oxidation while Unmitigated Stress Leads to Anorexia-Induced Lipolysis and Both Liver and Kidney Steatosis

Directory of Open Access Journals (Sweden)

Diane DeZwaan-McCabe

2017-05-01

Full Text Available The unfolded protein response (UPR, induced by endoplasmic reticulum (ER stress, regulates the expression of factors that restore protein folding homeostasis. However, in the liver and kidney, ER stress also leads to lipid accumulation, accompanied at least in the liver by transcriptional suppression of metabolic genes. The mechanisms of this accumulation, including which pathways contribute to the phenotype in each organ, are unclear. We combined gene expression profiling, biochemical assays, and untargeted lipidomics to understand the basis of stress-dependent lipid accumulation, taking advantage of enhanced hepatic and renal steatosis in mice lacking the ER stress sensor ATF6α. We found that impaired fatty acid oxidation contributed to the early development of steatosis in the liver but not the kidney, while anorexia-induced lipolysis promoted late triglyceride and free fatty acid accumulation in both organs. These findings provide evidence for both direct and indirect regulation of peripheral metabolism by ER stress.
ER Stress Inhibits Liver Fatty Acid Oxidation while Unmitigated Stress Leads to Anorexia-Induced Lipolysis and Both Liver and Kidney Steatosis.

Science.gov (United States)

DeZwaan-McCabe, Diane; Sheldon, Ryan D; Gorecki, Michelle C; Guo, Deng-Fu; Gansemer, Erica R; Kaufman, Randal J; Rahmouni, Kamal; Gillum, Matthew P; Taylor, Eric B; Teesch, Lynn M; Rutkowski, D Thomas

2017-05-30

The unfolded protein response (UPR), induced by endoplasmic reticulum (ER) stress, regulates the expression of factors that restore protein folding homeostasis. However, in the liver and kidney, ER stress also leads to lipid accumulation, accompanied at least in the liver by transcriptional suppression of metabolic genes. The mechanisms of this accumulation, including which pathways contribute to the phenotype in each organ, are unclear. We combined gene expression profiling, biochemical assays, and untargeted lipidomics to understand the basis of stress-dependent lipid accumulation, taking advantage of enhanced hepatic and renal steatosis in mice lacking the ER stress sensor ATF6α. We found that impaired fatty acid oxidation contributed to the early development of steatosis in the liver but not the kidney, while anorexia-induced lipolysis promoted late triglyceride and free fatty acid accumulation in both organs. These findings provide evidence for both direct and indirect regulation of peripheral metabolism by ER stress. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Toxicity of lead-contaminated sediment to mute swans

Science.gov (United States)

Day, D.D.; Beyer, W.N.; Hoffman, D.J.; Morton, Alexandra; Sileo, L.; Audet, D.J.; Ottinger, M.A.

2003-01-01

Most ecotoxicological risk assessments of wildlife emphasize contaminant exposure through ingestion of food and water. However, the role of incidental ingestion of sediment-bound contaminants has not been adequately appreciated in these assessments. This study evaluates the toxicological consequences of contamination of sediments with metals from hard-rock mining and smelting activities. Lead-contaminated sediments collected from the Coeur d'Alene River Basin in Idaho were combined with either a commercial avian maintenance diet or ground rice and fed to captive mute swans (Cygnus olor) for 6 weeks. Experimental treatments consisted of maintenance or rice diets containing 0, 12 (no rice group), or 24% highly contaminated (3,950 ug/g lead) sediment or 24% reference (9.7 ug/g lead) sediment. Although none of the swans died, the group fed a rice diet containing 24% lead-contaminated sediment were the most severely affected, experiencing a 24% decrease in mean body weight, including three birds that became emaciated. All birds in this treatment group had nephrosis; abnormally dark, viscous bile; and significant (p < 0.05) reductions in hematocrit and hemoglobin concentrations compared to their pretreatment levels. This group also had the greatest mean concentrations of lead in blood (3.2 ug/g), brain (2.2 ug/g), and liver (8.5 ug/g). These birds had significant (alpha = 0.05) increases in mean plasma alanine aminotransferase activity, cholesterol, and uric acid concentrations and decreased plasma triglyceride concentrations compared to all other treatment groups. After 14 days of exposure, mean protoporphyrin concentrations increased substantially, and mean delta-aminolevulinic acid dehydratase activity decreased by more than 95% in all groups fed diets containing highly contaminated sediments. All swans fed diets that contained 24% lead-contaminated sediment had renal acid-fast intranuclear inclusion bodies, which are diagnostic of lead poisoning in waterfowl. Body
Remediation of cadmium- and lead-contaminated agricultural soil by composite washing with chlorides and citric acid.

Science.gov (United States)

Li, Yu-jiao; Hu, Peng-jie; Zhao, Jie; Dong, Chang-xun

2015-04-01

Composite washing of cadmium (Cd)- and lead (Pb)-contaminated agricultural soil from Hunan province in China using mixtures of chlorides (FeCl3, CaCl2) and citric acid (CA) was investigated. The concentrations of composite washing agents for metal removal were optimized. Sequential extraction was conducted to study the changes in metal fractions after soil washing. The removal of two metals at optimum concentration was reached. Using FeCl3 mixed with CA, 44% of Cd and 23% of Pb were removed, and 49 and 32% by CaCl2 mixed with CA, respectively. The mechanism of composite washing was postulated. A mixture of chlorides and CA enhanced metal extraction from soil through the formation of metal-chloride and metal-citrate complexes. CA in extract solutions promoted the formation of metal-chloride complexes and reduced the solution pH. Composite washing reduced Cd and Pb in Fe-Mn oxide forms significantly. Chlorides and CA exerted a synergistic effect on metal extraction during composite washing.
The Basel Convention: effect on the Asian secondary lead industry

Science.gov (United States)

Elmer, J. W.

The Basel Convention has had a dramatic effect on the world trade in scrap materials. The scope of implementation is broader than was originally intended. This is due mainly to uncertainties created by a failure to distinguish between waste for disposal and waste destined for recycling. Spent lead/acid batteries and other lead scrap flows from OECD to non-OECD countries have been restricted to the point where secondary lead production is being affected. Export-import flows between OECD members have also changed as recycling is being contained within those countries. The economics of recycling in OECD countries may result in a smaller percentage of scrap being recycled. The established lead/acid battery industry in the Asian region, which relies heavily on imported scrap, will now be forced to import more finished metal, to maintain output. With strong economic growth forecast for the region, and no substitute for the lead-based battery, the supply situation is unlikely to ease.
Lead-Free Sn-Ce-O Composite Coating on Cu Produced by Pulse Electrodeposition from an Aqueous Acidic Sulfate Electrolyte

Science.gov (United States)

Sharma, Ashutosh; Das, Karabi; Das, Siddhartha

2017-10-01

Pulse-electrodeposited Sn-Ce-O composite solder coatings were synthesized on a Cu substrate from an aqueous acidic solution containing stannous sulfate (SnSO4·3H2O), sulfuric acid (H2SO4), and Triton X-100 as an additive. The codeposition was achieved by adding nano-cerium oxide powder in varying concentrations from 5 g/L to 20 g/L into the electrolytic bath. Microstructural characterization was carried out using x-ray diffraction (XRD), scanning electron microscopy, and transmission electron microscopy. The XRD analysis showed that the deposits consist mainly of tetragonal β (Sn) with reduced cerium oxide species. The composite coatings thus obtained exhibit a smaller grain size, possess higher microhardness, and a lower melting point than the monolithic Sn coating. The electrical resistivity of the developed composites increases, however, but lies within the permissible limits for current lead-free solder applications. Also, an optimum balance of properties in terms of microhardness, adhesion, melting point and resistivity can be obtained with 0.9 wt.% cerium oxide in the Sn matrix, which enables potential applications in solder joints and packaging.
Performance of lead-acid batteries. Experimental study and discharge process modelling; Desempenho de baterias chumbo-acido. Estudo experimental e modelamento do processo de descarga

Energy Technology Data Exchange (ETDEWEB)

Barreto, G; Bottura, C P [Universidade Estadual de Campinas, SP (Brazil); Oliveira, M G [Universidade Estadual de Campinas, SP (Brazil). Inst. de Quimica

1985-12-31

Commercial lead-acid batteries performance when continuously discharge is valued in this work. The model relating battery capacity and discharge current is confirmed through the analysis of experimental results relating voltage to time for various discharge currents. Such model was determined for the tested batteries and can be interpreted in terms of diffusional limitations and plate passivation. (author). 2 figs., 1 tab., 12 refs
Lead pollution in Islamabad

International Nuclear Information System (INIS)

Mohammad, D.; Khatoon, N.; Ishaque, M.; Ahmed, I.

1997-01-01

Lead pollution of urban area emanating from the vehicular exhaust alone is being labeled as one of the worst form of environmental degradation attracting our attention for remediation. For factual assessment samples were collected from different areas of Islamabad. These samples consisted of tree scrapings / peelings, which were dried and ground before undertaking analysis for the lead content. The samples were digested with an acid mixture to remove the organic matter and analyzed using GFAAS technique. A total of 81 samples have been analyzed. The results sowed a lead content varying in the range of 8-474 Mu g g/sup -1/) and 23 samples with Pb content <50 Mu g g-1 (8.0-50.0 Mu g g/sup -1/). Most of the samples also contained some growth which consisted of bacterial, algae and fugal cells and the results have been explained on the basis of Pb absorption by these cells. The procedure followed in this study is recommended for evaluation of lead pollution in urban areas. (author)
Toxic effects on bioaccumulation and hematological parameters of juvenile rockfish Sebastes schlegelii exposed to dietary lead (Pb) and ascorbic acid.

Science.gov (United States)

Kim, Jun-Hwan; Kang, Ju-Chan

2017-06-01

Juvenile rockfish, Sebastes schlegelii (mean length 11.3 ± 1.2 cm, and mean weight 32.5 ± 4.1 g) were exposed for four weeks to dietary lead (Pb 2+ ) at 0, 120, and 240 mg/L and ascorbic acid (AsA) at 100, 200, and 400 mg/L. The exposure concentrations and duration of significant Pb-induced accumulations in specific tissues of S. schlegelii were assessed. High levels of ascorbic acid significantly attenuated accumulations following exposure to dietary Pb. Dietary Pb exposure caused a significant increase in blood Pb concentrations, whereas red blood cell (RBC) count, hematocrit, and hemoglobin were significantly decreased. Notable changes were also observed in plasma calcium, magnesium, glucose, cholesterol, glutamic oxaloacetic transaminase (GOT), and glutamic pyruvate transaminase (GPT). The growth performance of S. schlegelii was significantly decreased. High doses AsA supplemention were effective in attenuating the changes brought about by dietary Pb exposure. Copyright © 2017 Elsevier Ltd. All rights reserved.
Quantitative analysis method for niobium in lead zirconate titanate

International Nuclear Information System (INIS)

Hara, Hideo; Hashimoto, Toshio

1986-01-01

Lead zirconate titanate (PZT) is a strong dielectric ceramic having piezoelectric and pyroelectric properties, and is used most as a piezoelectric material. Also it is a main component of lead lanthanum zirconate titanate (PLZT), which is a typical electrical-optical conversion element. Since these have been developed, the various electronic parts utilizing the piezoelectric characteristics have been put in practical use. The characteristics can be set up by changing the composition of PZT and the kinds and amount of additives. Among the additives, niobium has the action to make metallic ion vacancy in crystals, and by the formation of this vacancy, to ease the movement of domain walls in crystal grains, and to increase resistivity. Accordingly, it is necessary to accurately determine the niobium content for the research and development, quality control and process control. The quantitative analysis methods for niobium used so far have respective demerits, therefore, the authors examined the quantitative analysis of niobium in PZT by using an inductively coupled plasma emission spectro-analysis apparatus which has remarkably developed recently. As the result, the method of dissolving a specimen with hydrochloric acid and hydrofluoric acid, and masking unstable lead with ethylene diamine tetraacetic acid 2 sodium and fluoride ions with boric acid was established. The apparatus, reagents, the experiment and the results are reported. (Kako, I.)
Characterization and antioxidant activity of gallic acid derivative

Science.gov (United States)

Malinda, Krissan; Sutanto, Hery; Darmawan, Akhmad

2017-11-01

Peroxidase enzyme was used to catalyze the dimerization process of gallic acid. The structure of the dimerization product was characterized by 1H NMR and LC-MS-MS. The mechanism of gallic acid dimerization was also discussed. It was proposed that ellagic acid was formed through an oxidative coupling mechanism that lead to the formation of a C-C bond and followed by an intramolecular Fischer esterification mechanism that lead to the formation of two C-O bonds. Moreover, the antioxidant activity of gallic acid and ellagic acid were also studied. Gallic acid and ellagic acid exhibited the DPPH radical scavenging activity with IC50 values of 13.2 μM and 15.9 μM, respectively.
Does lead have a future? A twenty-year vision

International Nuclear Information System (INIS)

Stewart, D.M.

1994-01-01

There is a clear interdependence between the lead-producing industry and battery producers. An ever-increasing percentage of total lead production is consumed in batteries. Trends in lead production, consumption and uses, as well as lead prices are reviewed. A discussion is given of the impact of environmental pressures from government authorities and public opinion. A number of significant future opportunities are identified for the battery industry (and, hence, the lead industry) that together with the convenience and the cost competitiveness of the lead/acid battery ensures a strong future for the industry into the 21st century. (orig.)
Organic acid enhanced electrodialytic extraction of lead from contaminated soil fines in suspension

DEFF Research Database (Denmark)

Jensen, Pernille Erland; Ahring, Birgitte Kiær; Ottosen, Lisbeth M.

2007-01-01

for decontamination of the sludge was investigated. The ability of 11 organic acids to extract Pb from the fine fraction of contaminated soil (grains soil fines in suspension......The implementation of soil washing technology for the treatment of heavy metal contaminated soils is limited by the toxicity and unwieldiness of the remaining heavy metal contaminated sludge. In this work, the feasibility of combining electrodialytic remediation with heterotrophic leaching...... was tested. Five of the acids showed the ability to extract Ph from the soil fines in excess of the effect caused solely by pH changes. Addition of the acids, however, severely impeded EDR, hence promotion of EDR by combination with heterotrophic leaching was rejected. In contrast, enhancement of EDR...
Deposition and conversion in soil of acids, acid-forming substances and nutrients

International Nuclear Information System (INIS)

Mayer, R.

1990-01-01

Balancing of material depositions entries is the basis for their evaluation. The acid depositions must be put in relation to the acid neutralization capacity and to the buffer rate of the soil. Every 'excess' in depositons leads to an acid supply into the sub-soil and/or into the groundwater system. On the one hand, the nutrient depositions are interpreted in relation to the nutrient supplies of the soil and their availability to the plants; and on the other hand with a view to the nutrient depletion through the polants. Excesses can also lead to a (non-desirable) pollution of aquatic systems, or else to an enhanced nutrient supply in the soil. Balancing is therefore a necessary aid for the evaluation of material depositions from the atmosphere. (orig./EF) [de
Studies of doped negative valve-regulated lead-acid battery electrodes

Energy Technology Data Exchange (ETDEWEB)

Micka, K. [J. Heyrovsky Institute of Physical Chemistry, ASCR, 182 23 Prague 8 (Czech Republic); Calabek, M.; Baca, P.; Krivak, P.; Labus, R.; Bilko, R. [Department of Electrotechnology, University of Technology, 602 00 Brno (Czech Republic)

2009-06-01

Accelerated cycling in the partial state of charge regime showed conclusively that the improvement in cycle life of negative lead accumulator electrodes can be brought about not only by the addition of various sorts of powdered carbon into the active mass but also by the addition of other powdered inert materials like glass fibers, alumina, or titanium dioxide. Steric hindrance of the crystallization of lead sulfate in the electrode pores evidenced by ESEM microphotographs is considered as the main reason for this effect. The added powdered substances were practically without influence on the hydrogen overpotential; and their effect on the active material resistance was also negligible. (author)
Electrochemical Detection of Cadmium and Lead Complexes with Low Molecular Weight Organic Acids

Czech Academy of Sciences Publication Activity Database

Jaklová Dytrtová, J.; Šestáková, Ivana; Jakl, M.; Navrátil, Tomáš

2009-01-01

Roč. 21, 3-5 (2009), s. 573-579 ISSN 1040-0397 R&D Projects: GA ČR GA521/06/0496; GA ČR GA203/07/1195; GA AV ČR IAA400400806 Institutional research plan: CEZ:AV0Z40400503 Keywords : citric acid * oxalic acid * heavy metals * voltammetry Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.630, year: 2009
Differential changes in serum uric acid concentrations in sibutramine promoted weight loss in diabetes: results from four weeks of the lead-in period of the SCOUT trial

Directory of Open Access Journals (Sweden)

Caterson Ian D

2009-10-01

Full Text Available Abstract Background and aims Elevated levels of serum uric acid are associated with an increased risk of cardiovascular morbidity and mortality. The response of uric acid to weight loss therapy (lifestyle plus sibutramine in an overweight and obese cardiovascular high risk population was studied. Methods and results Data from a four week single-blind lead-in period of the Sibutramine Cardiovascular OUTcomes (SCOUT study were analyzed. 2584 patients (24% had diabetes mellitus (DM only, 1748 (16% had cardiovascular disease (CVD only and 6397 (60% had both DM + CVD. Uric acid concentrations (mean ± standard deviation at screening were significantly higher among patients with CVD compared to patients without CVD (p Conclusion A four week daily intake of sibutramine and life style changes was associated with significant reductions in mean uric acid levels. Changes in renal glucose load in diabetes seem to counteract a potential uricosuric effect of sibutramine. Trial Registration The trial is registered at ClinicalTrial.gov number: NCT00234832.
A technology for production of a ''Cureless'' paste containing a high concentration of tetrabasic lead sulfate and a low concentration of free lead

Energy Technology Data Exchange (ETDEWEB)

Boden, David P.; Loosemore, Daniel [Hammond Lead Products, Division of Hammond Group Inc., 6544 Osborn Avenue, Hammond, IN 46320 (United States)

2007-05-25

The conventional paste used to produce plates for lead-acid batteries comprises a mixture of leady oxide, water and sulfuric acid. Fibre and other additives, such as expander in negative plates, are added to improve paste properties and battery performance. Following pasting of the plates, they have to be cured to provide the correct chemical composition and crystal morphology, and to oxidize any residual free lead metal to lead monoxide. The desired result of the curing process is a positive plate with a high concentration of uniformly sized tetrabasic lead sulfate (4BS) crystals and with both positive and negative plates having a low concentration of free lead. Curing is a time-consuming and expensive process, which requires large numbers of chambers capable of being heated to 85 C and containing an atmosphere with a relative humidity greater than 95%. This process adds significant cost to the battery. (author)
Synthesis and characterization of new coordination polymer with l-proline amino acid ligand, new precursor for preparation of pure phase lead(II) oxide nanoparticles via thermal decomposition

Czech Academy of Sciences Publication Activity Database

Varzdar, S.; Hashemi, L.; Morsali, A.; Dušek, Michal

2017-01-01

Roč. 14, č. 11 (2017), s. 2255-2261 ISSN 1735-207X Institutional support: RVO:68378271 Keywords : coordination polymer * nanoparticle * lead(II) oxide * proline amino acid Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 1.407, year: 2016
Estimating the Size of the Renewable Energy Generators in an Isolated Solar-Biodiesel Microgrid with Lead-Acid Battery Storage

Directory of Open Access Journals (Sweden)

GRAMA Alin

2015-10-01

Full Text Available Climate change, fossil fuel decline, expensive power grid extensions focused the attention of scientist in developing electrical power systems that use as primary resources renewable energy generators. Romania has a high renewable energy potential and presents interest in developing renewable energy microgrids using: solar energy, wind energy, biomass Hydro, etc. The paper presents a method of estimating the size of the renewable energy generators in an isolated solar-biodiesel microgrid with lead-acid battery storage. The mathematical model is first presented and then an algorithm is developed to give an estimation of the size of the microgrid. The microgrid is installed in the region of Oradea, Romania. The results are validated through comparison with existing sizing software programs like: PV*Sol and PVSyst.
Update on Recovering Lead From Scrap Batteries

Science.gov (United States)

Cole, E. R.; Lee, A. Y.; Paulson, D. L.

1985-02-01

Previous work at the Bureau of Mines Rolla Research Center, U.S. Department of the Interior, resulted in successful development of a bench-scale, combination electrorefining-electrowinning method for recycling lead from scrap batteries by using waste fluosilicic acid (H2SiF6) as electrolyte.1,2 This paper describes larger scale experiments. Prior attempts to electrowin lead failed because large quantities of insoluble lead dioxide were deposited on the anodes at the expense of lead deposition on the cathodes. A major breakthrough was achieved with the discovery that lead dioxide formation at the anodes is prevented by adding a small amount of phosphorus to the electrolyte. The amount of PbO2 formed on the anodes during lead electrowinning was less than 1% of the total lead deposited on the cathodes. This work recently won the prestigious IR·100 award as one of the 100 most significant technological advances of 1984.
Lead neurotoxicity: In vitro and in vivo effects

International Nuclear Information System (INIS)

Rowles, T.K.

1989-01-01

Neuroglial cells, in particular astroglia, are thought to play a role in the neurotoxicity of lead. Two hypotheses have been proposed as possible cellular mechanism of this neurotoxicity: (1) lead affects intracellular levels of metals which mediate the toxic effects noted, and (2) lead affects intracellular heme biosynthesis which is then toxic to the cells. Zinc was found to have a profound effect on both intracellular lead levels and on cell numbers in lead-treated rat astroglia. A comparison of bovine and rat astroglia in culture indicated that the bovine cell cultures were not more sensitive to lead, even though calves are more sensitive. Lead was also shown to affect intracellular heme biosynthesis by a decrease in 14 C aminolevulinic acid incorporation into extractable heme in lead-treated rat astroglia. Finally, low levels of lead in immature guinea pigs caused changes in tissue levels of lead, iron, copper, and zinc with no change in weight gain or body:brain weight ratios

Optimization of the lead-acid battery for powering electric road vehicles

Energy Technology Data Exchange (ETDEWEB)

Friedheim, G [Accumulatorenfabriken Wilhem Hagen A.G., Soest (Germany, F.R.)

1977-01-01

A report is given on tests for the optimization of the lead accumulator for electric vehicles. The aim is to increase the specific energy (with adequate strength per cycle) and service life. For investigating this function systematic tests were made with different plate thicknesses and suitable plate surface. Further improvements were made by such factors, as the specific energy, which give low maintenance for the lead battery. Improved properties can be achieved by the construction and material of the casing and supports, and of the plate insulation.
Synthesis of bio-based methacrylic acid by decarboxylation of itaconic acid and citric acid catalyzed by solid transition-metal catalysts.

Science.gov (United States)

Le Nôtre, Jérôme; Witte-van Dijk, Susan C M; van Haveren, Jacco; Scott, Elinor L; Sanders, Johan P M

2014-09-01

Methacrylic acid, an important monomer for the plastics industry, was obtained in high selectivity (up to 84%) by the decarboxylation of itaconic acid using heterogeneous catalysts based on Pd, Pt and Ru. The reaction takes place in water at 200-250 °C without any external added pressure, conditions significantly milder than those described previously for the same conversion with better yield and selectivity. A comprehensive study of the reaction parameters has been performed, and the isolation of methacrylic acid was achieved in 50% yield. The decarboxylation procedure is also applicable to citric acid, a more widely available bio-based feedstock, and leads to the production of methacrylic acid in one pot in 41% selectivity. Aconitic acid, the intermediate compound in the pathway from citric acid to itaconic acid was also used successfully as a substrate. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Extraterrestrial material analysis: loss of amino acids during liquid-phase acid hydrolysis

Science.gov (United States)

Buch, Arnaud; Brault, Amaury; Szopa, Cyril; Freissinet, Caroline

2015-04-01

Searching for building blocks of life in extraterrestrial material is a way to learn more about how life could have appeared on Earth. With this aim, liquid-phase acid hydrolysis has been used, since at least 1970 , in order to extract amino acids and other organic molecules from extraterrestrial materials (e.g. meteorites, lunar fines) or Earth analogues (e.g. Atacama desert soil). This procedure involves drastic conditions such as heating samples in 6N HCl for 24 h, either under inert atmosphere/vacuum, or air. Analysis of the hydrolyzed part of the sample should give its total (free plus bound) amino acid content. The present work deals with the influence of the 6N HCl hydrolysis on amino acid degradation. Our experiments have been performed on a standard solution of 17 amino acids. After liquid-phase acid hydrolysis (6N HCl) under argon atmosphere (24 h at 100°C), the liquid phase was evaporated and the dry residue was derivatized with N-Methyl-N-(t-butyldimethylsilyl)trifluoroacetamide (MTBSTFA) and dimethylformamide (DMF), followed by gas chromatography-mass spectrometry analysis. After comparison with derivatized amino acids from the standard solution, a significant reduction of the chromatographic peak areas was observed for most of the amino acids after liquid-phase acid hydrolysis. Furthermore, the same loss pattern was observed when the amino acids were exposed to cold 6N HCl for a short amount of time. The least affected amino acid, i.e. glycine, was found to be 73,93% percent less abundant compared to the non-hydrolyzed standard, while the most affected, i.e. histidine, was not found in the chromatograms after hydrolysis. Our experiments thereby indicate that liquid-phase acid hydrolysis, even under inert atmosphere, leads to a partial or total loss of all of the 17 amino acids present in the standard solution, and that a quick cold contact with 6N HCl is sufficient to lead to a loss of amino acids. Therefore, in the literature, the reported increase
Lead contamination of inexpensive plastic jewelry

Energy Technology Data Exchange (ETDEWEB)

Yost, Jamie L. [Department of Chemistry, Ashland University, Ashland, Ohio (United States); Weidenhamer, Jeffrey D. [Department of Chemistry, Ashland University, Ashland, Ohio (United States)], E-mail: jweiden@ashland.edu

2008-04-15

The neurological hazards of lead to children are well-known. As a result of recent documented cases of lead poisoning, regulatory attention in the United States has focused on the lead content of children's metal jewelry. By contrast, little is known about the possible hazards of plastic jewelry items. The objective of this study was to determine whether inexpensive plastic jewelry is a possible source of toxic lead for children. Samples of more than 100 inexpensive plastic jewelry items were analyzed for lead content. Beads were screened by soaking in 1 M nitric acid. Nine items found to release more than 30 {mu}g of lead per bead were further tested for accessible lead, and scrapings of the bead coatings were analyzed for total lead content. The maximum accessible lead found was 49 {mu}g per bead, which is below the current US Consumer Product Safety Commission limit of 175 {mu}g. However, when the number of beads in each item was taken into account, six of the nine leaded samples contained more than 175 {mu}g accessible lead per item. The lead in these items appears to be associated with lead-based paints used to produce glossy coatings on imitation pearls and similar items. Coatings obtained by scraping individual beads contained 3.5-23% lead, which far exceeds the US regulatory limit of 0.06% lead in paints on items intended for children. Our results demonstrate that plastic jewelry items merit the attention of public health and consumer protection agencies seeking to limit the exposure of children to lead.
Lead contamination of inexpensive plastic jewelry

International Nuclear Information System (INIS)

Yost, Jamie L.; Weidenhamer, Jeffrey D.

2008-01-01

The neurological hazards of lead to children are well-known. As a result of recent documented cases of lead poisoning, regulatory attention in the United States has focused on the lead content of children's metal jewelry. By contrast, little is known about the possible hazards of plastic jewelry items. The objective of this study was to determine whether inexpensive plastic jewelry is a possible source of toxic lead for children. Samples of more than 100 inexpensive plastic jewelry items were analyzed for lead content. Beads were screened by soaking in 1 M nitric acid. Nine items found to release more than 30 μg of lead per bead were further tested for accessible lead, and scrapings of the bead coatings were analyzed for total lead content. The maximum accessible lead found was 49 μg per bead, which is below the current US Consumer Product Safety Commission limit of 175 μg. However, when the number of beads in each item was taken into account, six of the nine leaded samples contained more than 175 μg accessible lead per item. The lead in these items appears to be associated with lead-based paints used to produce glossy coatings on imitation pearls and similar items. Coatings obtained by scraping individual beads contained 3.5-23% lead, which far exceeds the US regulatory limit of 0.06% lead in paints on items intended for children. Our results demonstrate that plastic jewelry items merit the attention of public health and consumer protection agencies seeking to limit the exposure of children to lead
The hydrogen economy: a threat or an opportunity for lead-acid batteries?

Science.gov (United States)

Rand, D. A. J.; Dell, R. M.

There is mounting concern over the sustainability of global energy supplies. Among the key drivers are: (i) global warming, ocean surface acidification and air pollution, which imply the need to control and reduce anthropogenic emissions of greenhouse gases, especially emissions from transportation and thermal power stations; (ii) the diminishing reserves of oil and natural gas; (iii) the need for energy security adapted to each country, such as decreasing the dependence on fossil fuel imports (in particular, the vulnerability to volatile oil prices) from regions where there is political or economic instability; (iv) the expected growth in world population with the ever-increasing aspiration for an improved standard-of-living for all, especially in developing and poor nations. Hydrogen is being promoted world-wide as a total panacea for energy problems. As a versatile carrier for storing and transporting energy from any one of a myriad of sources to an electricity generator, it is argued that hydrogen will eventually replace, or at least greatly reduce, the reliance on fossil fuels. Not unexpectedly, the building of a 'hydrogen economy' presents great scientific and technological challenges in production, delivery, storage, conversion, and end-use. In addition, there are many policy, regulatory, economic, financial, investment, environmental and safety questions to be addressed. Notwithstanding these obstacles, it is indeed plausible that hydrogen will become increasingly deployed and will compete with traditional systems of energy storage and supply. Moreover, the case for hydrogen will be greatly strengthened if fuel cells, which are the key enabling technology, become more reliable, more durable, and less expensive. This paper examines the prospects for hydrogen as a universal energy-provider and considers the impact that its introduction might have on the present deployment of lead-acid batteries in mobile, stationary and road transportation applications.
Lithium increases ammonium excretion leading to altered urinary acid-base buffer composition.

Science.gov (United States)

Trepiccione, Francesco; Altobelli, Claudia; Capasso, Giovambattista; Christensen, Birgitte Mønster; Frische, Sebastian

2017-11-24

Previous reports identify a voltage dependent distal renal tubular acidosis (dRTA) secondary to lithium (Li + ) salt administration. This was based on the inability of Li + -treated patients to increase the urine-blood (U-B) pCO 2 when challenged with NaHCO 3 and, the ability of sodium neutral phosphate or Na 2 SO 4 administration to restore U-B pCO 2 in experimental animal models. The underlying mechanisms for the Li + -induced dRTA are still unknown. To address this point, a 7 days time course of the urinary acid-base parameters was investigated in rats challenged with LiCl, LiCitrate, NaCl, or NaCitrate. LiCl induced the largest polyuria and a mild metabolic acidosis. Li + -treatment induced a biphasic response. In the first 2 days, proper urine volume and acidification occurred, while from the 3rd day of treatment, polyuria developed progressively. In this latter phase, the LiCl-treated group progressively excreted more NH 4 + and less pCO 2 , suggesting that NH 3 /NH 4 + became the main urinary buffer. This physiological parameter was corroborated by the upregulation of NBCn1 (a marker of increased ammonium recycling) in the inner stripe of outer medulla of LiCl treated rats. Finally, by investigating NH 4 + excretion in ENaC-cKO mice, a model resistant to Li + -induced polyuria, a primary role of the CD was confirmed. By definition, dRTA is characterized by deficient urinary ammonium excretion. Our data question the presence of a voltage-dependent Li + -induced dRTA in rats treated with LiCl for 7 days and the data suggest that the alkaline urine pH induced by NH 3 /NH 4 + as the main buffer has lead to the interpretation dRTA in previous studies.
Lead Accumulation by Tall Fescue (Festuca arundinacea Schreb. Grown on a Lead-Contaminated Soil

Directory of Open Access Journals (Sweden)

D. Gilliard

2005-08-01

Full Text Available Phytoextraction is gaining acceptance as a cost-effective and environmentally friendly phytoremediation strategy for reducing toxic metal levels from contaminated soils. Cognizant of the potential of this phytoremediation technique as an alternative to expensive engineering-based remediation technologies, experiments were conducted to evaluate the suitability of some plants as phytoextraction species. From one of our preliminary studies, we found that tall fescue (Festuca arundinacea Schreb. cv. Spirit can tolerate and accumulate significant amounts of lead (Pb in its shoots when grown in Pb-amended sand. To further evaluate the suitability of tall fescue as one of the potential crop rotation species for phytoextraction, a study was conducted to determine whether the addition of ethylenediaminetetraacetic acid (EDTA alone or in combination with acetic acid can further enhance the shoot uptake of Pb. Seeds were planted in 3.8 L plastic pots containing top soil, peat, and sand (4:2:1, v:v:v spiked with various levels (0,1000, 2000 mg Pb/kg dry soil of lead. At six weeks after planting, aqueous solutions (0, 5 mmol/kg dry soil of EDTA and acetic acid (5 mmol/kg dry soil were applied to the root zone, and all plants were harvested a week later. Results revealed that tall fescue was relatively tolerant to moderate levels of Pb as shown by non-significant differences in root and shoot biomass among treatments. An exception to this trend however, was the slight reduction in root and shoot biomass of plants exposed to the highest Pb level in combination with the two chelates. Root Pb concentration increased with increasing level of soil-applied Pb. Further increases in root Pb concentrations were attributed to chelate amendments. Translocation index, which is a measure of the partitioning of the metal to the shoots, was significantly enhanced with chelate addition especially when both EDTA and acetic acid were used. Chelate-induced increases in
Lead and PCB's in canvasback ducks: Relationship between enzyme levels and residues in blood

Science.gov (United States)

Dieter, M.P.; Perry, M.C.; Mulhern, B.M.

1976-01-01

Blood samples were taken for two successive years from canvasback ducks trapped in the Chesapeake Bay. The first winter (1972?1973) five plasma enzymes known to respond to organochlorine poisoning were examined. Abnormal enzyme elevations suggested that 20% of the population sampled (23/115 ducks) might contain organochlorine contaminants, but no residue analyses were performed. The second winter (1974) two of the same enzymes, aspartate aminotransferase and lactate dehydrogenase, and a third enzyme known to be specifically inhibited by lead, delta-aminolevulinic acid dehydratase, were assayed in 95 blood samples. Blood residues of organochlorine compounds and of lead were determined in representative samples, and the correlations between residue levels and enzyme changes were examined. The enzyme bioassays in 1974 indicated that lead was a more prevalent environmental contaminant than organochlorine compounds in canvasback ducks; 17% of the blood samples had less than one-half of the normal delta-aminolevulinic acid dehydratase activity, but only 11% exhibited abnormal aspartate aminotransferase or lactate dehydrogenase activities. These findings were confirmed by residue analyses that demonstrated lead concentrations four times higher than background levels, but only relatively low organochlorine concentrations. There was a highly significant inverse correlation between delta-aminolevulinic acid dehydratase activity and blood lead concentrations (Pcontamination in waterfowl. In canvasback ducks 200 ppb of lead in the blood caused a 75% decrease in delta-aminolevulinic acid dehydratase activity, a magnitude of enzyme inhibition that disturbs heme synthesis and is regarded as detrimental in humans.
Initial occupational exposure to lead

Energy Technology Data Exchange (ETDEWEB)

Forni, A.; Cambiaghi, G.; Secchi, G.C.

1976-01-01

Serial chromosome and biochemical studies were carried out in 11 subjects before and during initial occupational exposure to moderate quantities of lead fumes in a storage battery plant. The rate of abnormal metaphases, mostly with chromatid and one-break chromosome aberrations, was approximately doubled after one month of work; it further increased after two months of work; remained in this range up to seven months of exposure; and then tended to decrease somewhat. Blood lead levels increased progressively in the first few months, then reached a steady state. Urinary lead and coproporphyrin levels increased sharply after one month of work, while urinary delta-aminolevulinic acid (ALA) levels increased moderately. The ALA dehydratase (ALAD) activity of red blood cells (RBCs) was reduced to almost 50 percent of the initial values after one month, decreased further in subsequent months, and remained decreased through the remainder of the study.
Research, development, and demonstration of lead-acid batteries for electric-vehicle propulsion. Annual report, 1980

Energy Technology Data Exchange (ETDEWEB)

1981-03-01

The first development effort in improving lead-acid batteries fore electric vehicles was the improvement of electric vehicle batteries using flat pasted positive plates and the second was for a tubular long life positive plate. The investigation of 32 component variables based on a flat pasted positive plate configuration is described. The experiment tested 96 - six volt batteries for characterization at 0, 25, and 40/sup 0/C and for cycle life capability at the 3 hour discharge rate with a one cycle, to 80% DOD, per day regime. Four positive paste formulations were selected. Two commercially available microporous separators were used in conjunction with a layer of 0.076 mm thick glass mat. Two concentrations of battery grade sulfuric acid were included in the test to determine if an increase in concentration would improve the battery capacity sufficient to offset the added weight of the more concentrated solution. Two construction variations, 23 plate elements with outside negative plates and 23 plate elements with outside positive plates, were included. The second development effort was an experiment designed to study the relationship of 32 component variables based on a tubular positive plate configuration. 96-six volt batteries were tested at various discharge rates at 0, 25, and 40/sup 0/C along with cycle life testing at 80% DOD of the 3 hour rate. 75 batteries remain on cycle life testing with 17 batteries having in excess of 365 life cycles. Preliminary conclusions indicate: the tubular positive plate is far more capable of withstanding deep cycles than is the flat pasted plate; as presently designed 40 Whr/kg can not be achieved, since 37.7 Whr/kg was the best tubular data obtained; electrolyte circulation is impaired due to the tight element fit in the container; and a redesign is required to reduce the battery weight which will improve the Whr/kg value. This redesign is complete and new molds have been ordered.
Fatty acid synthase inhibition in human breast cancer cells leads to malonyl-CoA-induced inhibition of fatty acid oxidation and cytotoxicity.

Science.gov (United States)

Thupari, J N; Pinn, M L; Kuhajda, F P

2001-07-13

Inhibition of fatty acid synthase (FAS) induces apoptosis in human breast cancer cells in vitro and in vivo without toxicity to proliferating normal cells. We have previously shown that FAS inhibition causes a rapid increase in malonyl-CoA levels identifying malonyl-CoA as a potential trigger of apoptosis. In this study we further investigated the role of malonyl-CoA during FAS inhibition. We have found that: [i] inhibition of FAS with cerulenin causes carnitine palmitoyltransferase-1 (CPT-1) inhibition and fatty acid oxidation inhibition in MCF-7 human breast cancer cells likely mediated by elevation of malonyl-CoA; [ii] cerulenin cytotoxicity is due to the nonphysiological state of increased malonyl-CoA, decreased fatty acid oxidation, and decreased fatty acid synthesis; and [iii] the cytotoxic effect of cerulenin can be mimicked by simultaneous inhibition of CPT-1, with etomoxir, and fatty acid synthesis with TOFA, an acetyl-CoA carboxylase (ACC) inhibitor. This study identifies CPT-1 and ACC as two new potential targets for cancer chemotherapy. Copyright 2001 Academic Press.
Dew point of gases with low sulfuric acid content

Energy Technology Data Exchange (ETDEWEB)

Fieg, J.

1981-07-01

Discusses control of air pollution caused by sulfur compounds in solid fuels during combustion. Excessive amount of oxygen during combustion leads to formation of sulfur trioxide. Sulfur trioxide reacts with water vapor and forms sulfuric acid. Chemical reactions which lead to formation of sulfuric acid are described. Conditions for sulfuric acid condensation are analyzed. Several methods for determining dew point of flue gases with low sulfuric acid content are reviewed: methods based on determination of electric conductivity of condensed sulfuric acid (Francis, Cheney, Kiyoure), method based on determination of sulfuric acid concentration in the gaseous phase and in the liquid phase after cooling (Lee, Lisle and Sensenbaugh, Ross and Goksoyr). (26 refs.) (In Polish)
Monitoring of lead levels in spices and food colors using atomic absorption spectroscopy

International Nuclear Information System (INIS)

Rahman, S.; Khalid, N.; Ahmad, S.

2001-01-01

The concentration of lead has been monitored in various commercial brands of spices and food colours using atomic absorption spectrometry after digestion in a mixture of nitric acid and perchloric acid. The reliability of the procedure used was checked by analyzing the standard reference materials namely wheat flour (NBS-1567) and rice flour (NBS-1568), for their lead contents. The determined concentration of lead ranged from 5.60 to 10.12 mg g-1 in food spices and from 1.62 to 1.81 mg g-1 in food colours. The study revealed that the piper nigrum contains higher lead contents as compared to capsicum. The effect of processing/milling on the concentration of lead in spices was also studied and discussed. The daily intake of lead by adults through spices and food colours was estimated and was found to be within the recommended WHO tolerance levels. (author)
Electrochemical corrosion of Pb-1 wt% Sn and Pb-2.5 wt% Sn alloys for lead-acid battery applications

Energy Technology Data Exchange (ETDEWEB)

Osorio, Wislei R.; Peixoto, Leandro C.; Garcia, Amauri [Department of Materials Engineering, State University of Campinas - UNICAMP, PO Box 612, 13083-970 Campinas, SP (Brazil)

2009-12-01

The aim of this study was to compare the electrochemical corrosion behavior of as-cast Pb-1 wt% Sn and Pb-2.5 wt% Sn alloy samples in a 0.5 M H{sub 2}SO{sub 4} solution at 25 C. A water-cooled unidirectional solidification system was used to obtain the as-cast samples. Electrochemical impedance spectroscopy (EIS) diagrams, potentiodynamic polarization curves and an equivalent circuit analysis were used to evaluate the electrochemical corrosion response. It was found that a coarse cellular array has a better electrochemical corrosion resistance than fine cells. The pre-programming of microstructure cell size of Pb-Sn alloys can be used as an alternative way to produce as-cast components of lead-acid batteries with higher corrosion resistance associated with environmental and economical aspects. (author)
Process for lead removal from rare earth

International Nuclear Information System (INIS)

Bollat, A.; Sabot, J.L.

1987-01-01

An aqueous solution of rare earth chlorides and lead chlorides, with a chloride concentration of at least 2 moles/liter and a pH between 2 and 4, is extracted by an alkylphosphonic acid ester and rare earth(s) is (are) recovered from the organic phase [fr
Preparation of lead titanate zirconate from metal citrates

International Nuclear Information System (INIS)

Bastos, C.M.R.

1994-01-01

Lead titanate zirconate (PZT) preparation from its metal constituent citrates have been investigated. Metal citrates were obtained by forced precipitation using a dehydration alcohol mixture. Salt solutions of lead nitrate and octahydrated zirconyl chloride, and titanium tetrachloride were treated separately with citric acid and ammonium hydroxide. Zirconium, titanium and lead oxides resulted from thermal decomposition of corresponding citrates at 500 0 C, 450 0 C and 250 0 C, respectively. Lead titanate (PT) and lead zirconate (P Z) were obtained by calcining at 450 0 C and 500 0 C, respectively, after adequate heating of citrates mechanically mixed in ethyl ether. PZT samples were obtained with different starting stoichiometry. Rhombohedral PZT-1 53/47 sample was prepared from co precipitating zirconyl ammonium and ammonium lead citrates in presence of ethanolic titanium oxide dispersion, and calcinating at 800 0 C. Rhombohedral PZT-q 52/48 sample was obtained from heating at 500 0 C for 2 hours a mixture of metal citrates coprecipitated by dehydration mixture of acetone-ethanol-formic acid (2:1:0,06). Tetragonal PZT-m stoichiometry 53/47 sample were obtained by calcining at after 600 0 C for 2 hours after heating a mechanically mixed metal citrates. PT phase arose at 400 0 C. PZT-m powders obtained in a range of 400 0 C-800 0 C were isostatically pressed, and sintered at 1100 0 C and 1200 0 C in saturated Pb O atmosphere. Rhombohedral sintered PZT was obtained with 7,78 g.cm -3 at 1200 0 C. (author). 123 refs, 53 figs, 32 tabs
Stable lead isotopes and lake sediments. A useful combination for the study of atmospheric lead pollution history

Energy Technology Data Exchange (ETDEWEB)

Renberg, I.; Braennvall, M.-L.; Bindler, R. [Department of Ecology and Environmental Science, Umea University, SE-901 87 Umea (Sweden); Emteryd, O. [Department of Forest Ecology, Swedish University of Agricultural Sciences, SE-901 83 Umea (Sweden)

2002-06-20

Analysis of stable lead isotopes and lead concentrations in lake-sediment deposits, not least in varved (annually-laminated) sediments, is a useful method to study lead pollution history. This paper presents details from a study of 31 lakes in Sweden. Using a strong acid digestion of sediment samples and ICP-MS analyses, we have found that Swedish lake sediments have a high natural (pre-pollution) 206[Pb]/207[Pb] ratio (mean 1.52{+-}0.18, range 1.28-2.01, n=31 lakes). In contrast, atmospheric lead pollution derived from metal smelting processes, coal burning and from alkyl-lead added to petrol has a lower ratio (<1.2). Consequently, when pollution lead deposition began approximately 3500 years ago, the lead isotope ratio of the sediments started to decline, and in modern sediments it is typically <1.2. Using the isotope and concentration values and a mixing model, the relative contribution of pollution and natural lead in sediment samples can be calculated. The pollution lead records of the Swedish lake sediments show a consistent picture of the atmospheric lead pollution history. Some noticeable features are the Roman peak, the large and permanent Medieval increase, peaks at approximately 1200 and 1530 ad, the rapid increase after World War II, the peak in the 1970s, and the large modern decline.
Lead exposure in US worksites: A literature review and development of an occupational lead exposure database from the published literature

Science.gov (United States)

Koh, Dong-Hee; Locke, Sarah J.; Chen, Yu-Cheng; Purdue, Mark P.; Friesen, Melissa C.

2016-01-01

Background Retrospective exposure assessment of occupational lead exposure in population-based studies requires historical exposure information from many occupations and industries. Methods We reviewed published US exposure monitoring studies to identify lead exposure measurement data. We developed an occupational lead exposure database from the 175 identified papers containing 1,111 sets of lead concentration summary statistics (21% area air, 47% personal air, 32% blood). We also extracted ancillary exposure-related information, including job, industry, task/location, year collected, sampling strategy, control measures in place, and sampling and analytical methods. Results Measurements were published between 1940 and 2010 and represented 27 2-digit standardized industry classification codes. The majority of the measurements were related to lead-based paint work, joining or cutting metal using heat, primary and secondary metal manufacturing, and lead acid battery manufacturing. Conclusions This database can be used in future statistical analyses to characterize differences in lead exposure across time, jobs, and industries. PMID:25968240
Different low-molecular-mass organic acids specifically control leaching of arsenic and lead from contaminated soil.

Science.gov (United States)

Ash, Christopher; Tejnecký, Václav; Borůvka, Luboš; Drábek, Ondřej

2016-04-01

Low-molecular-mass organic acids (LMMOA) are of key importance for mobilisation and fate of metals in soil, by functioning as ligands that increase the amount of dissolved metal in solution or by dissociation of metal binding minerals. Column leaching experiments were performed on soil polluted with As and Pb, in order to determine the specificity of LMMOA related release for individual elements, at varying organic acid concentrations. Acetic, citric and oxalic acids were applied in 12h leaching experiments over a concentration range (0.5-25 mM) to soil samples that represent organic and mineral horizons. The leaching of As followed the order: oxalic>citric>acetic acid in both soils. Arsenic leaching was attributed primarily to ligand-enhanced dissolution of mineral oxides followed by As released into solution, as shown by significant correlation between oxalic and citric acids and content of Al and Fe in leaching solutions. Results suggest that subsurface mineral soil layers are more vulnerable to As toxicity. Leaching of Pb from both soils followed the order: citric>oxalic>acetic acid. Mineral soil samples were shown to be more susceptible to leaching of Pb than samples characterised by a high content of organic matter. The leaching efficiency of citric acid was attributed to formation of stable complexes with Pb ions, which other acids are not capable of. Results obtained in the study are evidence that the extent of As and Pb leaching in contaminated surface and subsurface soil depends significantly on the types of carboxylic acid involved. The implications of the type of acid and the specific element that can be mobilised become increasingly significant where LMMOA concentrations are highest, such as in rhizosphere soil. Copyright © 2016 Elsevier B.V. All rights reserved.

Long-range downstream effects of urban runoff and acid mine drainage in the Debed River, Armenia: insights from lead isotope modeling

International Nuclear Information System (INIS)

Kurkjian, Robert; Dunlap, Charles; Flegal, A. Russell

2004-01-01

Lead concentrations and isotopic compositions measured along 80 km of the Debed River in the Republic of Armenia provide new insights into the geochemical and physical controls on riparian Pb transport by allowing comparison of the long-range, downstream impacts of acid mine drainage with runoff from an industrialized city. The modern background Pb concentration in Armenian surface waters is estimated to be ∼0.01 μg/L, based on analyses of remote alpine rivers in Armenia. The lead concentration in the Debed River is 8 μg/L (800 times background) after passing through Vanadzor, the second largest industrial city in Armenia; it then decreases to 1 μg/L before the Debed River flows into the Alaverdi mining district. There, the Debed River receives waters from two mining drainage streams with Pb concentrations >3000 μg/L, but those concentrations decrease 3 orders of magnitude to ∼3 μg/L by the time the river exits Armenia and flows into the Republic of Georgia. Isotope mixing plots show shifts in Pb isotope composition as the river flows out of Vanadzor, evidencing the mixture of an average terrestrial Pb composition ( 206 Pb/ 207 Pb ∼ 1.17; 208 Pb/ 207 Pb ∼ 2.45) with past leaded gasoline and other industrial Pb emissions retained in the river's sediments within that region ( 208 Pb/ 207 Pb ≤ 2.45). The isotopic composition again shifts (e.g., 208 Pb/ 207 Pb ≥ 2.46) as the river passes through the Alaverdi mining district, where isotopic ratios in the water are characteristic of Pb in the area's massive sulfide deposits. Modeling both downstream elemental concentrations and Pb isotopic compositions further resolves the physical and chemical behavior of the contaminants in the river system. A multi-element model of concentration gradients in the acid mine drainage streams indicates Pb is attenuated by Al(OH) 3 precipitation (54% of the loss) and by adsorption onto other particles settling out of the water column (46% of the loss). Modeling of Pb
Radiogenic lead-208 abundance 88.34 %

International Nuclear Information System (INIS)

Seneda, Jose A.; Abrao, Alcidio; Dias, Mauro S.; Kakazu, Mauricio H.; Salvador, Vera L.R.; Queiroz, Carlos A.S.; Rocha, Soraya M.R. da; Sato, Key

2009-01-01

Brazil has a long tradition in thorium technology, from the monazite ores mining until the production of the nuclear grade thorium compounds. Early in 1969 the Institute of Energy and Nuclear Research (IPEN) designed a project for a pilot plant installation to purify the thorium compounds, based on the solvent extraction technique. Thorium compounds used came from monazite's industrialization. During the course of the operation of this plant, a crude sludge were formed containing thorium not extracted and the whole rare earths, plus minor impurities like sodium, titanium, zirconium, hafnium, iron, silicon, phosphate and the thorium daughters were accumulated. Included is the radiogenic lead-208. This sludge, hereafter named 'RETOTER', was treated with hydrochloric acid and the lead was separated and recovered by anion exchange technology. The lead-208 was analyzed by mass spectrometry (HR-ICPMS) technique. The lead-208 abundance measure was 88.34%, this allowed the calculation of the thermal neutron capture cross section of σ 0 γ = 14,6 +/- 0.7 mb, considerably lower than the σ 0 γ = 174.2 +/- 0.7 mb value of the natural lead. (author)
Superconducting lead particles produced by chemical techniques

Science.gov (United States)

Fariss, T. L.; Nixon, W. E.; Bucelot, T. J.; Deaver, B. S., Jr.; Mitchell, J. W.

1982-09-01

The superconductivity of extremely small lead particles has been studied as a function of size, surface condition, and connectivity using chemical techniques to produce particles of well-controlled size and shape suspended in insulating media. Approximately monodisperse suspensions of equiaxed, rod, and lath-shaped particles of lead halides and other lead compounds suspended in gelatin, polyacrylamide, polyvinylpyrrolidone, polyvinyl alcohol, methyl cellulose, and hydroxyethyl cellulose have been produced. These particles have been reduced to pseudomorphs of lead in the liquid phase or the suspensions have been coated on substrates and dried before reduction. Reducing solutions containing aminoiminomethanesulfinic acid are effective with particles of lead halides, lead phosphate, lead sulfate, and lead tartrate. Suspensions of smaller discrete lead particles have also been produced by direct reduction of solutions of soluble lead salts containing suitable polymers, chelating, and stabilizing agents. Dispersions with mean particle dimensions between 3 nm and 5 μm, and a narrow size-frequency distribution, have been produced. The superconductivity of the particles has been characterized by measurements of the magnetization as a function of temperature and magnetic field. The larger particles have a transition temperature of 7.2 K, the same as bulk lead; however, for particles of characteristic dimensions less than 20 nm, the transition temperature is lower by ˜0.1 K.
Superconducting lead particles produced by chemical techniques

International Nuclear Information System (INIS)

Fariss, T.L.; Nixon, W.E.; Bucelot, T.J.; Deaver, B.S. Jr.; Mitchell, J.W.

1982-01-01

The superconductivity of extremely small lead particles has been studied as a function of size, surface condition, and connectivity using chemical techniques to produce particles of well-controlled size and shape suspended in insulating media. Approximately monodisperse suspensions of equiaxed, rod, and lath-shaped particles of lead halides and other lead compounds suspended in gelatin, polyacrylamide, polyvinylpyrrolidone, polyvinyl alcohol, methyl cellulose, and hydroxyethyl cellulose have been produced. These particles have been reduced to pseudomorphs of lead in the liquid phase or the suspensions have been coated on substrates and dried before reduction. Reducing solutions containing aminoiminomethanesulfinic acid are effective with particles of lead halides, lead phosphate, lead sulfate, and lead tartrate. Suspensions of smaller discrete lead particles have also been produced by direct reduction of solutions of soluble lead salts containing suitable polymers, chelating, and stabilizing agents. Dispersions with mean particle dimensions between 3 nm and 5 μm, and a narrow size-frequency distribution, have been produced. The superconductivity of the particles has been characterized by measurements of the magnetization as a function of temperature and magnetic field. The larger particles have a transition temperature of 7.2 K, the same as bulk lead; however, for particles of characteristic dimensions less than 20 nm, the transition temperature is lower by approx.0.1 K
State of the art of smelting lead-acid battery scrap

Energy Technology Data Exchange (ETDEWEB)

Melin, A

1977-02-01

A discussion is given of the economic importance of lead recovery and of scrap recycling in the battery industry. Various possibiliies of processing battery scrap, either by direct smelting or by smelting after preparaton are discussed, and the BBU, the Stolberger, and the Tonnolli methods are compared
Lead sulfate nano- and microparticles in the acid plant blow-down generated at the sulfuric acid plant of the El Teniente mine, Chile.

Science.gov (United States)

Barassi, Giancarlo M; Klimsa, Martin; Borrmann, Thomas; Cairns, Mathew J; Kinkel, Joachim; Valenzuela, Fernando

2014-12-01

The acid plant 'blow-down' (also called weak acid) produced at El Teniente mine in Chile was characterized. This liquid waste (tailing) is generated during the cooling and cleaning of the smelter gas prior to the production of sulfuric acid. The weak acid was composed of a liquid and a solid phase (suspended solids). The liquid phase of the sample analyzed in this study mainly contained Cu (562 mg L(-1)), SO4(2-) (32 800 mg L(-1)), Ca (1449 mg L(-1)), Fe (185 mg L(-1)), As (6 mg L(-1)), K (467 mg L(-1)) and Al (113 mg L(-1)). Additionally, the sample had a pH-value and total acidity of 0.45 and 2970 mg L(-1) as CaCO3, respectively. Hence, this waste was classified as extremely acidic and with a high metal content following the Ficklin diagram classification. Elemental analysis using atomic absorption, inductively coupled plasma, X-ray diffraction and electron microscopy showed that the suspended solids were anglesite (PbSO4) nano- and microparticles ranging from 50 nm to 500 nm in diameter.
Effects of lead poisoning on various plasma constituents in the Canada goose

International Nuclear Information System (INIS)

March, G.L.; John, T.M.; McKeown, B.A.; Sileo, L.; George, J.C.

1976-01-01

Plasma glucose, free fatty acid and uric acid levels were measured in lead-poisoned Canada geese (Branta canadensis). Although plasma glucose levels were only slightly elevated, uric acid was significantly higher and free fatty acids were significantly lower. Altered plasma levels were attributed to increased protein catabolism and renal dysfunction. Plasma level of growth hormone and prolactin was assessed by radioimmunoassay. Growth hormone remained unchanged while prolactin was unusually high. The increased prolactin levels may reflect an effort to stabilize free fatty acids. 30 references, 1 figure, 2 tables
Environmental Lead Pollution in an Urban Soft-water Area

Science.gov (United States)

Beattie, A. D.; Moore, M. R.; Devenay, W. T.; Miller, A. R.; Goldberg, A.

1972-01-01

An investigation has been reported on the clinical and metabolic effects of lead acquired by soft domestic water from lead plumbing systems in 23 Glasgow households. The lead content of water from cold taps was up to 18 times the upper acceptable limit and was proportional to the amount of lead in the plumbing system. The blood lead of 71 inhabitants of these houses showed a significant positive correlation with water lead content. Delta-aminolaevulic acid dehydrase activity, an extremely sensitive indicator of lead exposure, showed a significant negative correlation with water-lead content. Atmospheric lead was within acceptable limits in all but one house and no significant correlation could be found with biochemical measurements. A small number of clinical abnormalities were found but could not be directly attributed to lead toxicity. The results of the study underline the possible danger to health of lead plumbing systems in soft-water regions. PMID:5031207
Catalysis of the Oligomerization of O-Phospho-Serine, Aspartic Acid, or Glutamic Acid by Cationic Micelles

Science.gov (United States)

Bohler, Christof; Hill, Aubrey R., Jr.; Orgel, Leslie E.

1996-01-01

Treatment of relatively concentrated aqueous solutions of 0-phospho-serine (50 mM), aspartic acid (100 mM) or glutamic acid (100 mM) with carbonyldiimidazole leads to the formation of an activated intermediate that oligomerizes efficiently. When the concentration of amino acid is reduced tenfold, few long oligomers can be detected. Positively-charged cetyltrimethyl ammonium bromide micelles concentrate the negatively-charged activated intermediates of the amino acids at their surfaces and catalyze efficient oligomerization even from dilute solutions.
Lead isotopic compositions of environmental certified reference materials for an inter-laboratory comparison of lead isotope analysis

International Nuclear Information System (INIS)

Aung, Nyein Nyein; Uryu, Tsutomu; Yoshinaga, Jun

2004-01-01

Lead isotope ratios, viz. 207 Pb/ 206 Pb and 208 Pb/ 206 Pb, of the commercially available certified reference materials (CRMs) issued in Japan are presented with an objective to provide a data set, which will be useful for the quality assurance of analytical procedures, instrumental performance and method validation of the laboratories involved in environmental lead isotope ratio analysis. The analytical method used in the present study was inductively coupled plasma quadrupole mass spectrometry (ICPQMS) presented by acid digestion and with/without chemical separation of lead from the matrix. The precision of the measurements in terms of the relative standard deviation (RSD) of triplicated analyses was 0.19% and 0.14%, for 207 Pb/ 206 Pb and 208 Pb/ 206 Pb, respectively. The trueness of lead isotope ratio measurements of the present study was tested with a few CRMs, which have been analyzed by other analytical methods and reported in various literature. The lead isotopic ratios of 18 environmental matrix CRMs (including 6 CRMs analyzed for our method validation) are presented and the distribution of their ratios is briefly discussed. (author)
Resolution in QCM sensors for the viscosity and density of liquids: application to lead acid batteries.

Science.gov (United States)

Cao-Paz, Ana María; Rodríguez-Pardo, Loreto; Fariña, José; Marcos-Acevedo, Jorge

2012-01-01

In battery applications, particularly in automobiles, submarines and remote communications, the state of charge (SoC) is needed in order to manage batteries efficiently. The most widely used physical parameter for this is electrolyte density. However, there is greater dependency between electrolyte viscosity and SoC than that seen for density and SoC. This paper presents a Quartz Crystal Microbalance (QCM) sensor for electrolyte density-viscosity product measurements in lead acid batteries. The sensor is calibrated in H(2)SO(4) solutions in the battery electrolyte range to obtain sensitivity, noise and resolution. Also, real-time tests of charge and discharge are conducted placing the quartz crystal inside the battery. At the same time, the present theoretical "resolution limit" to measure the square root of the density-viscosity product [Formula: see text] of a liquid medium or best resolution achievable with a QCM oscillator is determined. Findings show that the resolution limit only depends on the characteristics of the liquid to be studied and not on frequency. The QCM resolution limit for [Formula: see text] measurements worsens when the density-viscosity product of the liquid is increased, but it cannot be improved by elevating the work frequency.
Determination of regression functions for the charging and discharging processes of valve regulated lead-acid batteries

Directory of Open Access Journals (Sweden)

Vukić Vladimir Đ.

2012-01-01

Full Text Available Following a deep discharge of AGM SVT 300 valve-regulated lead-acid batteries using the ten-hour discharge current, the batteries were charged using variable current. In accordance with the obtained results, exponential and polynomial functions for the approximation of the specified processes were analyzed. The main evaluation instrument for the quality of the implemented approximations was the adjusted coefficient of determination R-2. It was perceived that the battery discharge process might be successfully approximated with both an exponential and the second order polynomial function. On all the occasions analyzed, values of the adjusted coefficient of determination were greater than 0.995. The charging process of the deeply discharged batteries was successfully approximated with the exponential function; the measured values of the adjusted coefficient of determination being nearly 0.95. Apart from the high measured values of the adjusted coefficient of determination, polynomial approximations of the second and third order did not provide satisfactory results regarding the interpolation of the battery charging characteristics. A possibility for a practical implementation of the procured regression functions in uninterruptible power supply systems was described.
The sublethal effects of copper and lead on the haematology and ...

African Journals Online (AJOL)

Toxicity bioassays were conducted on groovy mullet, Liza dumerili, using copper and lead, in order to assess how these metals affected their blood haematology and acid-base balance. Short-term (96 hours) exposure to lead caused significantly more haematological response [PCO2] than copper, when compared to the ...
Fatty Acid Incubation of Myotubues from Humans with Type 2 Diabetes Leads to Enhanced Release of Beta Oxidation Products Due to Impaired Fatty Acid Oxidation

DEFF Research Database (Denmark)

Wensaas, Andreas J; Rustan, Arild C; Just, Marlene

2008-01-01

Objective: Increased availability of fatty acids is important for accumulation of intracellular lipids and development of insulin resistance in human myotubes. It is unknown whether different types of fatty acids like eicosapentaenoic acid (EPA) or tetradecylthioacetic acid (TTA) influence...... these processes. Research Design and Methods: We examined fatty acid and glucose metabolism, and gene expression in cultured human skeletal muscle cells from control and T2D individuals after four days preincubation with EPA or TTA. Results: T2D myotubes exhibited reduced formation of CO(2) from palmitic acid (PA....... EPA markedly enhanced TAG accumulation in myotubes, more pronounced in T2D cells. TAG accumulation and fatty acid oxidation were inversely correlated only after EPA preincubation, and total level of acyl-CoA was reduced. Glucose oxidation (CO(2) formation) was enhanced and lactate production decreased...
Blood, urine, and hair kinetic analysis following an acute lead intoxication.

Science.gov (United States)

Ho, G; Keutgens, A; Schoofs, R; Kotolenko, S; Denooz, R; Charlier, C

2011-01-01

A case of lead exposure resulting from the accidental ingestion of a lead-containing solution is reported. Because of clinical management rapidly performed through chelation therapy by 2,3-dimercaptopropane sulfonate sodium and meso-2,3-dimercaptosuccinic acid, blood lead levels of this 51-year-old patient were moderate (412.9 μg/L) and no clinical symptoms were observed. Numerous blood and urine samples were collected for kinetic analysis of lead elimination. However, we report the first case in which hair samples were analyzed to determine the excretion level of lead after acute intoxication.
A novel surface cleaning method for chemical removal of fouling lead layer from chromium surfaces

International Nuclear Information System (INIS)

Gholivand, Kh.; Khosravi, M.; Hosseini, S.G.; Fathollahi, M.

2010-01-01

Most products especially metallic surfaces require cleaning treatment to remove surface contaminations that remain after processing or usage. Lead fouling is a general problem which arises from lead fouling on the chromium surfaces of bores and other interior parts of systems which have interaction with metallic lead in high temperatures and pressures. In this study, a novel chemical solution was introduced as a cleaner reagent for removing metallic lead pollution, as a fouling metal, from chromium surfaces. The cleaner aqueous solution contains hydrogen peroxide (H 2 O 2 ) as oxidizing agent of lead layer on the chromium surface and acetic acid (CH 3 COOH) as chelating agent of lead ions. The effect of some experimental parameters such as acetic acid concentration, hydrogen peroxide concentration and temperature of the cleaner solution during the operation on the efficiency of lead cleaning procedure was investigated. The results of scanning electron microscopy (SEM) showed that using this procedure, the lead pollution layer could be completely removed from real chromium surfaces without corrosion of the original surface. Finally, the optimum conditions for the complete and fast removing of lead pollution layer from chromium surfaces were proposed. The experimental results showed that at the optimum condition (acetic acid concentration 28% (V/V), hydrogen peroxide 8% (V/V) and temperature 35 deg. C), only 15-min time is needed for complete removal of 3 g fouling lead from a chromium surface.
Apparent Consumption vs. Total Consumption--A Lead-Acid Battery Case Study

Science.gov (United States)

Wilburn, David R.; Buckingham, David A.

2006-01-01

Introduction: This report compares estimates of U.S. apparent consumption of lead with estimates of total U.S. consumption of this mineral commodity from a materials flow perspective. The difference, attributed to the amount of lead contained in imported and exported products, was found to be significant for this sector. The study also assesses the effects of including mineral commodities incorporated in manufactured products on the interpretation of observed trends in minerals consumption and trade. Materials flow is a systems approach to understanding what happens to the materials we use from the time a material is extracted, through its processing and manufacturing, to its ultimate disposition. The U.S. Geological Survey (USGS) provides accurate and detailed mineral production and mineral commodity consumption statistics that are essential for government, nongovernment organizations, and the public to gain a better understanding of how and where materials are used and their effect on the environment and society. Published statistics on mineral apparent consumption are limited to estimates of consumption of raw material forms (ore, concentrate, and [or] refined metal). For this study, apparent consumption is defined as mine production + secondary refined production + imports (concentrates and refined metal) ? exports (concentrates and refined metal) + adjustments for government and industry stock changes. These estimates do not account for the amount of mineral commodities contained in manufactured products that are imported to the United States, nor do they deduct the amount of these mineral commodities contained in manufactured products that are exported from the United States. When imports or exports of manufactured products contribute significantly to the total use of a particular raw material, an estimate of consumption that does not consider the incorporated forms of these mineral commodities within imported or exported manufactured products can be either
Microstructure and electrochemical corrosion behavior of a Pb-1 wt%Sn alloy for lead-acid battery components

Energy Technology Data Exchange (ETDEWEB)

Peixoto, Leandro C.; Osorio, Wislei R.; Garcia, Amauri [Department of Materials Engineering, University of Campinas - UNICAMP, PO Box 612, 13083-970, Campinas - SP (Brazil)

2009-07-15

The aim of this study was to evaluate the effect of solidification cooling rates on the as-cast microstructural morphologies of a Pb-1 wt%Sn alloy, and to correlate the resulting microstructure with the corresponding electrochemical corrosion resistance in a 0.5 M H{sub 2}SO{sub 4} solution at 25 C. Cylindrical low-carbon steel and insulating molds were employed permitting the two extremes of a significant range of solidification cooling rates to be experimentally examined. Electrochemical impedance spectroscopy (EIS) diagrams, potentiodynamic polarization curves and an equivalent circuit analysis were used to evaluate the electrochemical corrosion response of Pb-1 wt%Sn alloy samples. It was found that lower cooling rates are associated with coarse cellular arrays which result in better corrosion resistance than fine cells which are related to high cooling rates. The experimental results have shown that that the pre-programming of microstructure cell size of Pb-Sn alloys can be used as an alternative way to produce as-cast components of lead-acid batteries with higher corrosion resistance. (author)
Lead-nickel electrochemical batteries

CERN Document Server

Glaize, Christian

2012-01-01

The lead-acid accumulator was introduced in the middle of the 19th Century, the diverse variants of nickel accumulators between the beginning and the end of the 20th Century. Although old, these technologies are always very present on numerous markets. Unfortunately they are still not used in optimal conditions, often because of the misunderstanding of the internal electrochemical phenomena.This book will show that batteries are complex systems, made commercially available thanks to considerable amounts of scientific research, empiricism and practical knowledge. However, the design of
Maternal Diabetes Leads to Adaptation in Embryonic Amino Acid Metabolism during Early Pregnancy.

Science.gov (United States)

Gürke, Jacqueline; Hirche, Frank; Thieme, René; Haucke, Elisa; Schindler, Maria; Stangl, Gabriele I; Fischer, Bernd; Navarrete Santos, Anne

2015-01-01

During pregnancy an adequate amino acid supply is essential for embryo development and fetal growth. We have studied amino acid composition and branched chain amino acid (BCAA) metabolism at day 6 p.c. in diabetic rabbits and blastocysts. In the plasma of diabetic rabbits the concentrations of 12 amino acids were altered in comparison to the controls. Notably, the concentrations of the BCAA leucine, isoleucine and valine were approximately three-fold higher in diabetic rabbits than in the control. In the cavity fluid of blastocysts from diabetic rabbits BCAA concentrations were twice as high as those from controls, indicating a close link between maternal diabetes and embryonic BCAA metabolism. The expression of BCAA oxidizing enzymes and BCAA transporter was analysed in maternal tissues and in blastocysts. The RNA amounts of three oxidizing enzymes, i.e. branched chain aminotransferase 2 (Bcat2), branched chain ketoacid dehydrogenase (Bckdha) and dehydrolipoyl dehydrogenase (Dld), were markedly increased in maternal adipose tissue and decreased in liver and skeletal muscle of diabetic rabbits than in those of controls. Blastocysts of diabetic rabbits revealed a higher Bcat2 mRNA and protein abundance in comparison to control blastocysts. The expression of BCAA transporter LAT1 and LAT2 were unaltered in endometrium of diabetic and healthy rabbits, whereas LAT2 transcripts were increased in blastocysts of diabetic rabbits. In correlation to high embryonic BCAA levels the phosphorylation amount of the nutrient sensor mammalian target of rapamycin (mTOR) was enhanced in blastocysts caused by maternal diabetes. These results demonstrate a direct impact of maternal diabetes on BCAA concentrations and degradation in mammalian blastocysts with influence on embryonic mTOR signalling.

Maternal Diabetes Leads to Adaptation in Embryonic Amino Acid Metabolism during Early Pregnancy.

Directory of Open Access Journals (Sweden)

Jacqueline Gürke

Full Text Available During pregnancy an adequate amino acid supply is essential for embryo development and fetal growth. We have studied amino acid composition and branched chain amino acid (BCAA metabolism at day 6 p.c. in diabetic rabbits and blastocysts. In the plasma of diabetic rabbits the concentrations of 12 amino acids were altered in comparison to the controls. Notably, the concentrations of the BCAA leucine, isoleucine and valine were approximately three-fold higher in diabetic rabbits than in the control. In the cavity fluid of blastocysts from diabetic rabbits BCAA concentrations were twice as high as those from controls, indicating a close link between maternal diabetes and embryonic BCAA metabolism. The expression of BCAA oxidizing enzymes and BCAA transporter was analysed in maternal tissues and in blastocysts. The RNA amounts of three oxidizing enzymes, i.e. branched chain aminotransferase 2 (Bcat2, branched chain ketoacid dehydrogenase (Bckdha and dehydrolipoyl dehydrogenase (Dld, were markedly increased in maternal adipose tissue and decreased in liver and skeletal muscle of diabetic rabbits than in those of controls. Blastocysts of diabetic rabbits revealed a higher Bcat2 mRNA and protein abundance in comparison to control blastocysts. The expression of BCAA transporter LAT1 and LAT2 were unaltered in endometrium of diabetic and healthy rabbits, whereas LAT2 transcripts were increased in blastocysts of diabetic rabbits. In correlation to high embryonic BCAA levels the phosphorylation amount of the nutrient sensor mammalian target of rapamycin (mTOR was enhanced in blastocysts caused by maternal diabetes. These results demonstrate a direct impact of maternal diabetes on BCAA concentrations and degradation in mammalian blastocysts with influence on embryonic mTOR signalling.
A novel approach in acidic disinfection through inhibition of acid resistance mechanisms; Maleic acid-mediated inhibition of glutamate decarboxylase activity enhances acid sensitivity of Listeria monocytogenes.

Science.gov (United States)

Paudyal, Ranju; Barnes, Ruth H; Karatzas, Kimon Andreas G

2018-02-01

Here it is demonstrated a novel approach in disinfection regimes where specific molecular acid resistance systems are inhibited aiming to eliminate microorganisms under acidic conditions. Despite the importance of the Glutamate Decarboxylase (GAD) system for survival of Listeria monocytogenes and other pathogens under acidic conditions, its potential inhibition by specific compounds that could lead to its elimination from foods or food preparation premises has not been studied. The effects of maleic acid on the acid resistance of L. monocytogenes were investigated and found that it has a higher antimicrobial activity under acidic conditions than other organic acids, while this could not be explained by its pKa or Ka values. The effects were found to be more pronounced on strains with higher GAD activity. Maleic acid affected the extracellular GABA levels while it did not affect the intracellular ones. Maleic acid had a major impact mainly on GadD2 activity as also shown in cell lysates. Furthermore, it was demonstrated that maleic acid is able to partly remove biofilms of L. monocytogenes. Maleic acid is able to inhibit the GAD of L. monocytogenes significantly enhancing its sensitivity to acidic conditions and together with its ability to remove biofilms, make a good candidate for disinfection regimes. Copyright © 2017 Elsevier Ltd. All rights reserved.
Interactions between lignosulphonates and the components of the lead-acid battery. Part 1. Adsorption isotherms

Science.gov (United States)

Myrvold, Bernt O.

The expander performs at least five different tasks in the battery. It is a fluidiser for the negative paste. It controls the formation stage of the battery. It controls the shape and size of the lead sulphate crystals formed upon discharge, and thus prevents the sintering of the active mass. It controls the rate of the lead to lead sulphate oxidation during discharge. Finally, it affects the charge acceptance. To gain more understanding of these different effects the interaction between lead, lead(II) oxide, lead(IV) oxide, lead sulphate, barium sulphate and carbon black and the experimental lignosulphonate (LS) expander UP-414 has been investigated. We also compared with Vanisperse A and several other lignosulphonates, to elucidate the mechanisms operating. In most cases, we have studied concentration ranges that are both higher and lower than those normally encountered in batteries. There is no adsorption of lignosulphonates to pure lead surfaces. Adsorption to lead sulphate is a slow process. In the presence of lead ions lignosulphonates will also adsorb to lead. The adsorption to lead(II) oxide is a fast process, and a strong adsorption occurs. In all these cases, it is preferably the high molecular weight fraction that interacts with the solid surfaces. Lead ions leaching from the surface complexes with lignosulphonates to give a more hydrophobic species. This allows the normally negatively charged lignosulphonate to adsorb to the negatively charged substrates. The lignosulphonates have an ability to complex lead ions and keep them solvated. This confirms previous observations of the lignosulphonates ability to promote the dissolution-precipitation mechanism for lead sulphate formation on the expense of the solid-state reaction.
Removing antimony from waste lead storage batteries alloy by vacuum displacement reaction technology.

Science.gov (United States)

Liu, Tiantian; Qiu, Keqiang

2018-04-05

With the wide application of lead acid battery, spent lead acid battery has become a serious problem to environmental protection and human health. Though spent battery can be a contaminant if not handled properly, it is also an important resource to obtain refined lead. Nowadays, the Sb-content in lead storage batteries is about 0.5-3 wt%, which is higher than the Sb-content in the crude lead. However, there are few reports about the process of removing antimony from high-antimony lead bullion. In this study, vacuum displacement reaction technology, a new process for removing antimony from high-antimony lead melts, was investigated. During this process, lead oxide was added to the system and antimony from lead melts was converted into antimony trioxide, which easily was evaporated under vacuum so that antimony was removed from lead melts. The experimental results demonstrated that Sb-content in lead melts decreased from 2.5% to 23 ppm under following conditions: mass ratio of PbO/lead bullion of 0.33, residual gas pressure of 30 Pa, melt temperature of 840 °C, reaction time of 60 min. The distillate gotten can be used as by-product to produce antimony white. Moreover, this study is of importance to recycling of waste lead storage batteries alloy. Copyright © 2018 Elsevier B.V. All rights reserved.
Nrf2 protects human bladder urothelial cells from arsenite and monomethylarsonous acid toxicity

International Nuclear Information System (INIS)

Wang Xiaojun; Sun Zheng; Chen Weimin; Eblin, Kylee E.; Gandolfi, Jay A.; Zhang, Donna D.

2007-01-01

Arsenic is widely spread in our living environment and imposes a big challenge on human health worldwide. Arsenic damages biological systems through multiple mechanisms including the generation of reactive oxygen species. The transcription factor Nrf2 regulates the cellular antioxidant response that protects cells from various insults. In this study, the protective role of Nrf2 in arsenic toxicity was investigated in a human bladder urothelial cell line, UROtsa. Using a UROtsa cell line stably infected with Nrf2-siRNA, we clearly demonstrate that compromised Nrf2 expression sensitized the cells to As(III)- and MMA(III)-induced toxicity. On the other hand, the activation of the Nrf2 pathway by tert-butylhydroquinone (tBHQ) and sulforaphane (SF), the known Nrf2-inducers, rendered UROtsa cells more resistant to As(III) and MMA(III). Furthermore, the wild-type mouse embryo fibroblast (WT-MEF) cells were protected from As(III)- and MMA(III)-induced toxicity following Nrf2 activation by tBHQ or SF, whereas neither tBHQ nor SF conferred protection in the Nrf2 -/- MEF cells, demonstrating that tBHQ- or SF-mediated protection against As(III)- and MMA(III)-induced toxicity depends on Nrf2 activation. These results, obtained by both loss of function and gain of function analyses, clearly demonstrate the protective role of Nrf2 in arsenic-induced toxicity. The current work lays the groundwork for using Nrf2 activators for therapeutic and dietary interventions against adverse effects of arsenic
A field operational test on valve-regulated lead-acid absorbent-glass-mat batteries in micro-hybrid electric vehicles. Part I. Results based on kernel density estimation

Science.gov (United States)

Schaeck, S.; Karspeck, T.; Ott, C.; Weckler, M.; Stoermer, A. O.

2011-03-01

In March 2007 the BMW Group has launched the micro-hybrid functions brake energy regeneration (BER) and automatic start and stop function (ASSF). Valve-regulated lead-acid (VRLA) batteries in absorbent glass mat (AGM) technology are applied in vehicles with micro-hybrid power system (MHPS). In both part I and part II of this publication vehicles with MHPS and AGM batteries are subject to a field operational test (FOT). Test vehicles with conventional power system (CPS) and flooded batteries were used as a reference. In the FOT sample batteries were mounted several times and electrically tested in the laboratory intermediately. Vehicle- and battery-related diagnosis data were read out for each test run and were matched with laboratory data in a data base. The FOT data were analyzed by the use of two-dimensional, nonparametric kernel estimation for clear data presentation. The data show that capacity loss in the MHPS is comparable to the CPS. However, the influence of mileage performance, which cannot be separated, suggests that battery stress is enhanced in the MHPS although a battery refresh function is applied. Anyway, the FOT demonstrates the unsuitability of flooded batteries for the MHPS because of high early capacity loss due to acid stratification and because of vanishing cranking performance due to increasing internal resistance. Furthermore, the lack of dynamic charge acceptance for high energy regeneration efficiency is illustrated. Under the presented FOT conditions charge acceptance of lead-acid (LA) batteries decreases to less than one third for about half of the sample batteries compared to new battery condition. In part II of this publication FOT data are presented by multiple regression analysis (Schaeck et al., submitted for publication [1]).
Adsorption of lead from aqueous solutions by poly (methyl methacrylate)

International Nuclear Information System (INIS)

Din, M.; Hussain, R.

1992-01-01

The adsorption capability of commercially manufactured poly (methyl methacrylate) for lead in aqueous medium has been investigated. Percent adsorption and distribution coefficient values have been determined in relation to the shaking time, amount of adsorbent, pH effects and concentration of lead in the solution. The experimental results are compatible with Freundlich type of adsorption behavior. It is discernible from the experimental results that poly (methyl methacrylate) can be used for the removal of lead from slightly acidic aqueous solutions. (author)
Zinc and lead detoxifying abilities of humic substances relevant to environmental bacterial species.

Science.gov (United States)

Perelomov, L V; Sarkar, Binoy; Sizova, O I; Chilachava, K B; Shvikin, A Y; Perelomova, I V; Atroshchenko, Y M

2018-04-30

The effect of humic substances (HS) and their different fractions (humic acids (HA) and hymatomelanic acids (HMA)) on the toxicity of zinc and lead to different strains of bacteria was studied. All tested bacteria demonstrated a lower resistance to zinc than lead showing minimum inhibitory concentrations of 0.1 - 0.3mM and 0.3-0.5mM, respectively. The highest resistance to lead was characteristic of Pseudomonas chlororaphis PCL1391 and Rhodococcus RS67, while Pseudomonas chlororaphis PCL1391 showed the greatest resistance to zinc. The combined fractions of HS and HA alone reduced zinc toxicity at all added concentrations of the organic substances (50 - 200mgL -1 ) to all microorganisms, while hymatomelanic acids reduced zinc toxicity to Pseudomonas chlororaphis PCL1391 at 200mgL -1 organic concentration only. The HS fractions imparted similar effects on lead toxicity also. This study demonstrated that heavy metal toxicity to bacteria could be reduced through complexation with HS and their fractions. This was particularly true when the metal-organic complexes held a high stability, and low solubility and bioavailability. Copyright © 2018 Elsevier Inc. All rights reserved.
Exposure to acute severe hypoxia leads to increased urea loss and disruptions in acid-base and ionoregulatory balance in dogfish sharks (Squalus acanthias).

Science.gov (United States)

Zimmer, Alex M; Wood, Chris M

2014-01-01

The effects of acute moderate (20% air O2 saturation; 6-h exposure) and severe (5% air O2 saturation; 4-h exposure) hypoxia on N-waste, acid-base, and ion balance in dogfish sharks (Squalus acanthias suckleyi) were evaluated. We predicted that the synthesis and/or retention of urea, which are active processes, would be inhibited by hypoxia. Exposure to moderate hypoxia had negligible effects on N-waste fluxes or systemic physiology, except for a modest rise in plasma lactate. Exposure to severe hypoxia led to a significant increase in urea excretion (Jurea), while plasma, liver, and muscle urea concentrations were unchanged, suggesting a loss of urea retention. Ammonia excretion (Jamm) was elevated during normoxic recovery. Moreover, severe hypoxia led to disruptions in acid-base balance, indicated by a large increase in plasma [lactate] and substantial decreases in arterial pHa and plasma [Formula: see text], as well as loss of ionic homeostasis, indicated by increases in plasma [Mg(2+)], [Ca(2+)], and [Na(+)]. We suggest that severe hypoxia in dogfish sharks leads to a reduction in active gill homeostatic processes, such as urea retention, acid-base regulation and ionoregulation, and/or an osmoregulatory compromise due to increased functional gill surface area. Overall, the results provide a comprehensive picture of the physiological responses to a severe degree of hypoxia in an ancient fish species.
Lead sorption-desorption from organic residues.

Science.gov (United States)

Duarte Zaragoza, Victor M; Carrillo, Rogelio; Gutierrez Castorena, Carmen M

2011-01-01

Sorption and desorption are mechanisms involved in the reduction of metal mobility and bioavailability in organic materials. Metal release from substrates is controlled by desorption. The capacity of coffee husk and pulp residues, vermicompost and cow manure to adsorb Pb2+ was evaluated. The mechanisms involved in the sorption process were also studied. Organic materials retained high concentrations of lead (up to 36,000 mg L(-1)); however, the mechanisms of sorption varied according to the characteristics of each material: degree of decomposition, pH, cation exchange capacity and percentage of organic matter. Vermicompost and manure removed 98% of the Pb from solution. Lead precipitated in manure and vermicompost, forming lead oxide (PbO) and lead ferrite (PbFe4O7). Adsorption isotherms did not fit to the typical Freundlich and Langmuir equations. Not only specific and non-specific adsorption was observed, but also precipitation and coprecipitation. Lead desorption from vermicompost and cow manure was less than 2%. For remediation of Pb-polluted sites, the application of vermicompost and manure is recommended in places with alkaline soils because Pb precipitation can be induced, whereas coffee pulp residue is recommended for acidic soils where Pb is adsorbed.
Understanding the function and performance of carbon-enhanced lead-acid batteries : milestone report for the DOE Energy Storage Systems Program (FY11 Quarter 4: July through September 2011).

Energy Technology Data Exchange (ETDEWEB)

Ferreira, Summer Rhodes; Shane, Rodney (East Penn Manufacturing, Lyon Station, PA); Enos, David George

2011-10-01

This report describes the status of research being performed under CRADA No. SC10/01771.00 (Lead/Carbon Functionality in VRLA Batteries) between Sandia National Laboratories and East Penn Manufacturing, conducted for the U.S. Department of Energy's Energy Storage Systems Program. The Quarter 4 Milestone was completed on time. The milestone entails the initiation of high rate, partial state of charge (HRPSoC) cycling of the carbon enhanced batteries. The morphology, porosity, and porosity distribution within the plates after 1k and 10k cycles were documented, illustrating the changes which take place in the early life of the carbon containing batteries, and as the battery approaches failure due to hard sulfation for the control battery. Longer term cycling on a subset of the received East Penn cells containing different carbons (and a control) continues, and will progress into FY12. Carbon has been explored as an addition to lead-acid battery electrodes in a number of ways. Perhaps the most notable to date has been the hybrid 'Ultrabattery' developed by CSIRO where an asymmetric carbon-based electrochemical capacitor is combined with a lead-acid battery into a single cell, dramatically improving high-rate partial-state-of-charge (HRPSoC) operation. As illustrated below, the 'Ultrabattery' is a hybrid device constructed using a traditional lead-acid battery positive plate (i.e., PbO2) and a negative electrode consisting of a carbon electrode in parallel with a lead-acid negative plate. This device exhibits a dramatically improved cycle life over traditional VRLA batteries, as well as increased charge power and charge acceptance. The 'Ultrabattery' has been produced successfully by both The Furukawa Battery Co. and East Penn Manufacturing. An example illustrating the dramatic improvement in cycle life of the Ultrabattery over a conventional VRLA battery is shown in a graph. In addition to the aforementioned hybrid device, carbon has
Lead-Related Genetic Loci, Cumulative Lead Exposure and Incident Coronary Heart Disease: The Normative Aging Study

Science.gov (United States)

Weisskopf, Marc G.; Sparrow, David; Schwartz, Joel; Hu, Howard; Park, Sung Kyun

2016-01-01

Background Cumulative exposure to lead is associated with cardiovascular outcomes. Polymorphisms in the δ-aminolevulinic acid dehydratase (ALAD), hemochromatosis (HFE), heme oxygenase-1 (HMOX1), vitamin D receptor (VDR), glutathione S-transferase (GST) supergene family (GSTP1, GSTT1, GSTM1), apolipoprotein E (APOE),angiotensin II receptor-1 (AGTR1) and angiotensinogen (AGT) genes, are believed to alter toxicokinetics and/or toxicodynamics of lead. Objectives We assessed possible effect modification by genetic polymorphisms in ALAD, HFE, HMOX1, VDR, GSTP1, GSTT1, GSTM1, APOE, AGTR1 and AGT individually and as the genetic risk score (GRS) on the association between cumulative lead exposure and incident coronary heart disease (CHD) events. Methods We used K-shell-X-ray fluorescence to measure bone lead levels. GRS was calculated on the basis of 22 lead-related loci. We constructed Cox proportional hazard models to compute adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for incident CHD. We applied inverse probability weighting to account for potential selection bias due to recruitment into the bone lead sub-study. Results Significant effect modification was found by VDR, HMOX1, GSTP1, APOE, and AGT genetic polymorphisms when evaluated individually. Further, the bone lead-CHD associations became larger as GRS increases. After adjusting for potential confounders, a HR of CHD was 2.27 (95%CI: 1.50–3.42) with 2-fold increase in patella lead levels, among participants in the top tertile of GRS. We also detected an increasing trend in HRs across tertiles of GRS (p-trend = 0.0063). Conclusions Our findings suggest that lead-related loci as a whole may play an important role in susceptibility to lead-related CHD risk. These findings need to be validated in a separate cohort containing bone lead, lead-related genetic loci and incident CHD data. PMID:27584680
Effectiveness of leaded petrol phase-out in Tianjin, China based on the aerosol lead concentration and isotope abundance ratio

International Nuclear Information System (INIS)

Wang Wan; Liu Xiande; Zhao Liwei; Guo, Dongfa; Tian Xiaodan; Adams, Freddy

2006-01-01

The phase-out of leaded petrol has been a measure widely used to reduce atmospheric lead pollution. Since the 1980s, China began to promote unleaded petrol. In order to assess the effectiveness of the measure an isotope fingerprint technique was applied for aerosol samples in the city of Tianjin. After dilute acid leaching, the lead concentration and isotope abundance ratios were determined for 123 samples collected in Tianjin during eight years (1994-2001). The 206 Pb / 207 Pb ratio was lower in summer, when coal combustion emission was low and vehicle exhaust became more important, indicating that the 206 Pb / 207 Pb ratio of leaded petrol in Tianjin is lower than that of aerosol samples. The 206 Pb / 207 Pb ratio gradually increased from 1994 to 2001, a trend that suggests that the contribution from vehicle exhaust was diminishing. Overall, the measurements matched well with national statistical data of leaded and unleaded petrol production. After the nationwide switch to unleaded gasoline, comprehensive control measures are urgently needed to reduce air lead pollution in China, as aerosol lead reduced slightly but remains at a relatively high level
Acid Deposition Phenomena

International Nuclear Information System (INIS)

Ramadan, A.E.K.

2004-01-01

Acid deposition, commonly known as acid rain, occurs when emissions from the combustion of fossil fuels and other industrial processes undergo complex chemical reactions in the atmosphere and fall to the earth as wet deposition (rain, snow, cloud, fog) or dry deposition (dry particles, gas). Rain and snow are already naturally acidic, but are only considered problematic when less than a ph of 5.0 The main chemical precursors leading to acidic conditions are atmospheric concentrations of sulfur dioxide (SO 2 ) and nitrogen oxides (NO x ). When these two compounds react with water, oxygen, and sunlight in the atmosphere, the result is sulfuric (H 2 SO 4 ) and nitric acids (HNO 3 ), the primary agents of acid deposition which mainly produced from the combustion of fossil fuel and from petroleum refinery. Airborne chemicals can travel long distances from their sources and can therefore affect ecosystems over broad regional scales and in locations far from the sources of emissions. According to the concern of petroleum ministry with the environment and occupational health, in this paper we will discussed the acid deposition phenomena through the following: Types of acidic deposition and its components in the atmosphere Natural and man-made sources of compounds causing the acidic deposition. Chemical reactions causing the acidic deposition phenomenon in the atmosphere. Factors affecting level of acidic deposition in the atmosphere. Impact of acid deposition. Procedures for acidic deposition control in petroleum industry
Electrowinning of lead powder from chloride leach liquor

Energy Technology Data Exchange (ETDEWEB)

Owais, Ashour [Suez Canal Univ., Suez (Egypt). Metallurgical and Materials Engineering Dept.

2012-11-15

Electrowinning of lead powder from chloride leach liquor obtained from secondary lead slag leached in hydrochloric acid is the main aim of this work. The resulted lead chloride solution (leachate) containing 2.2 wt.-% Pb and 1.24 wt.-% HCl was electrowon in an electrolytic cell containing one graphite plate as inert anode and two lead sheets as starting permanent cathodes. Different electrolysis parameters such as current density, electrolyte temperature and electrolyte stirring rate were studied. As indicated by SEM, EDX and XRD analyses, fine and pure (100 % Pb) powders with a dispersed and needle-like shape were formed with cathodic current efficiency up to 67.9 % and electrical energy demand ranges from 0.809 to 4.998 kWh/kg Pb with productivity up to 2.63 g/Ah. (orig.)
Uric acid nephrolithiasis: An update.

Science.gov (United States)

Cicerello, Elisa

2018-04-01

Uric acid nephrolithiasis appears to increase in prevalence. While a relationship between uric acid stones and low urinary pH has been for long known, additional association with various metabolic conditions and pathophysiological basis has recently been elucidated. Some conditions such as diabetes and metabolic syndrome disease, excessive dietary intake, and increased endogenous uric acid production and/or defect in ammoniagenesis are associated with low urinary pH. In addition, the phenomenon of global warming could result in an increase in areas with greater climate risk for uric acid stone formation. There are three therapeutic steps to be taken for management of uric acid stones: identification of urinary pH profiles, assessment of urinary volume status, and identification of disorders leading to excessive uric acid production. However, the most important factor for uric acid stone formation is acid urinary pH, which is a prerequisite for uric acid precipitation. This article reviews recent insights into the pathophysiology of uric acid stones and their management.
Atomic absorption spectrometric determination of copper, zinc, and lead in geological materials

Science.gov (United States)

Sanzolone, R.F.; Chao, T.T.

1976-01-01

An atomic absorption spectrometric method is described for the determination of copper, zinc, and lead in geological materials. The sample is digested with HF-HCl-H2O2; the final solution for analysis is in 10 % (v/v) HCl. Copper and zinc are determined directly by aspirating the solution into an air-acetylene flame. A separate aliquot of the solution is used for determination of lead; lead is extracted into TOPO-MIBK from the acidic solution in the presence of iodide and ascorbic acid. For a 0.50-g sample, the limits of determination are 10-2000 p.p.m. for Cu and Zn, and 5-5000 p.p.m. for Pb. As much as 40 % Fe or Ca. and 10 % Al, Mg, or Mn in the sample do not interfere. The proposed method can be applied to the determination of copper, zinc, and lead in a wide range of geological materials including iron- and manganese-rich, calcareous and carbonate samples. ?? 1976.
Localized accumulation of lead within and among bones from lead-dosed goats

International Nuclear Information System (INIS)

Cretacci, Yan; Parsons, Patrick J.

2010-01-01

The principal aim of this study was to gain a better understanding of where lead (Pb) accumulates and how it is distributed, within the bones of dosed goats. Adult goats were periodically dosed with Pb over a number of years for the primary purpose of producing blood pools containing endogenously bound Pb, for the New York State Blood Lead Proficiency Testing Program. Bone samples (e.g., primarily tibia, femur, humerus, and radius) were collected post-mortem from 11 animals and were analyzed for Pb content by acid digestion and electrothermal atomic absorption spectrometry (ETAAS or GFAAS). Average tibia Pb levels were found to correlate strongly with the cumulative Pb dose (r 2 =0.81). However, the concentration of Pb in different bones and even within a small area of the same bone varied tremendously. Blood-rich trabecular (spongy) bone, such as the patella and calcaneus, were much more enriched in Pb than was cortical (compact) bone. In some dosed animals, the Pb concentration in the tibia was markedly higher at the proximal and distal ends of the bone compared to the mid-shaft. The implications of these findings with regard to the noninvasive measurement of lead in bone by XRF methods are discussed.
Localized accumulation of lead within and among bones from lead-dosed goats

Energy Technology Data Exchange (ETDEWEB)

Cretacci, Yan [Laboratory of Inorganic and Nuclear Chemistry, Wadsworth Center, New York State Department of Health, P.O. Box 509, Albany, NY 12201-0509 (United States); Department of Environmental Health Sciences, School of Public Health, The University at Albany, P.O. Box 509, Albany, NY 12201-0509 (United States); Parsons, Patrick J., E-mail: pparsons@wadsworth.org [Laboratory of Inorganic and Nuclear Chemistry, Wadsworth Center, New York State Department of Health, P.O. Box 509, Albany, NY 12201-0509 (United States); Department of Environmental Health Sciences, School of Public Health, The University at Albany, P.O. Box 509, Albany, NY 12201-0509 (United States)

2010-01-15

The principal aim of this study was to gain a better understanding of where lead (Pb) accumulates and how it is distributed, within the bones of dosed goats. Adult goats were periodically dosed with Pb over a number of years for the primary purpose of producing blood pools containing endogenously bound Pb, for the New York State Blood Lead Proficiency Testing Program. Bone samples (e.g., primarily tibia, femur, humerus, and radius) were collected post-mortem from 11 animals and were analyzed for Pb content by acid digestion and electrothermal atomic absorption spectrometry (ETAAS or GFAAS). Average tibia Pb levels were found to correlate strongly with the cumulative Pb dose (r{sup 2}=0.81). However, the concentration of Pb in different bones and even within a small area of the same bone varied tremendously. Blood-rich trabecular (spongy) bone, such as the patella and calcaneus, were much more enriched in Pb than was cortical (compact) bone. In some dosed animals, the Pb concentration in the tibia was markedly higher at the proximal and distal ends of the bone compared to the mid-shaft. The implications of these findings with regard to the noninvasive measurement of lead in bone by XRF methods are discussed.
Soft plastic bread packaging: lead content and reuse by families.

Science.gov (United States)

Weisel, C; Demak, M; Marcus, S; Goldstein, B D

1991-06-01

The presence of lead in labels painted on soft plastic bread packaging was evaluated. Lead was detected on the outside of 17 of 18 soft plastic bread bags that were analyzed, with an average of 26 +/- 6 mg per bag with lead. Of 106 families questioned, 16 percent of respondents reported turning the bags inside out before reusing for food storage, thus putting food in contact with the lead paint. We estimate that a weak acid, such as vinegar, could readily leach 100 micrograms of lead from a painted plastic bag within 10 minutes. Further, lead and other metals painted on food packaging of any type becomes part of the municipal waste stream subject to incineration and to land-filling. The use of lead in packaging presents an unnecessary risk to public health.

Carbohydrate metabolism during prolonged exercise and recovery: interactions between pyruvate dehydrogenase, fatty acids, and amino acids

DEFF Research Database (Denmark)

Mourtzakis, Marina; Saltin, B.; Graham, T.

2006-01-01

During prolonged exercise, carbohydrate oxidation may result from decreased pyruvate production and increased fatty acid supply and ultimately lead to reduced pyruvate dehydrogenase (PDH) activity. Pyruvate also interacts with the amino acids alanine, glutamine, and glutamate, whereby the decline...... amino acid taken up during exercise and recovery. Alanine and glutamine were also associated...... with pyruvate metabolism, and they comprised 68% of total amino-acid release during exercise and recovery. Thus reduced pyruvate production was primarily associated with reduced carbohydrate oxidation, whereas the greatest production of pyruvate was related to glutamate, glutamine, and alanine metabolism...
EFFECT OF SOME PLANT OILS ON THE FATTY ACIDS OF HUMP BEETLE GIBBIUM PSYLLOIDES

International Nuclear Information System (INIS)

ABBASY, S.A.; ALY, W.M.; REZK, S.A.

2008-01-01

The efficiency of some plant oils (sesame oil, camphor oil, castor oil and camomile oil) as insecticides were studied on newly emerged males and females Gibbium psylloids and also the effect of LC50 of each plant oils on fatty acids composition and relative concentration were determined. The obtained results showed that sesame oil had proved to be more effective with it's advantage over other tested oils of being used at lower concentration and it followed by chamomile oil then camphor oil and finally castor oil. The susceptibility of the males and females to plant oils was the same. There were differences in the number and relative concentration of fatty acids between males and females. Nine fatty acids were detected by the analysis of the whole body of untreated males , these fatty acids are capric (C10) , lauric (C12) , myristic (C14), palmiloleic (C16), margic (C17), stearic (C18) , oleic (C18:1) , linoleic (C18:2) and linolenic (C18:3) . Treatments of males with LC50 sesame oil lead to the appearance of ten fatty acids with increase of caprylic acid (C8) while LC50 chamomile oil lead to the appearance of six fatty acids and fatty acid with C10 , C18:1 and C18:2 were disappeared as compared to control. LC50 of camphor oil lead to the appearance of ten fatty acids and castor oil lead to the appearance of six fatty acids. In untreated females, five fatty acids with C12 , C16 , C17 , C18 and C18:1 were detected. Treatments with sesame oil lead to the appearance of new fatty acid with C18:2 and chamomile oil lead to the appearance of nine fatty acids with increase of C8 , C10 , C14 and C18:2 as compared with untreated females. Camphor oil treatment lead to the appearance of nine fatty acids with increase of four fatty acids with C6 , C8 , C10 and C18:2 as compared to untreated females and fatty acid with C18:1 was disappeared in the treatments. Castor oil leads to the appearance of seven fatty acids. The relative concentration of C12 was the highest fatty acid in
Branched-chain fatty acid biosynthesis in a branched-chain amino acid aminotransferase mutant of Staphylococcus carnosus

DEFF Research Database (Denmark)

Beck, Hans Christian

2005-01-01

Fatty acid biosynthesis by a mutant strain of Staphylococcus carnosus deficient in branched-chain amino acid aminotransferase (IlvE) activity was analysed. This mutant was unable to produce the appropriate branched-chain alpha-ketoacid precursors for branched-chain fatty acid biosynthesis from...... in rich medium and growth in defined medium supplemented with 2-methylpropanoic acid lead to extensive alteration of the fatty acid composition in the cell membrane. In rich medium, a change from 51.7% to 17.1% anteiso-C15:0, and from 3.6% to 33.9% iso-C14:0 fatty acids as compared to the wild-type strain...... for 2-methylpropanoic acid production, revealing that the IlvE protein plays an important, but not essential role in the biosynthesis of branched-chain fatty acids and secondary metabolites in S. carnosus....
Lead in the environment

Science.gov (United States)

Pattee, Oliver H.; Pain, Deborah J.; Hoffman, David J.; Rattner, Barnett A.; Burton, G. Allen; Cairns, John

2003-01-01

Anthropogenic uses of lead have probably altered its availability and environmental distribution more than any other toxic element. Consequently, lead concentrations in many living organisms may be approaching thresholds of toxicity for the adverse effects of lead. Such thresholds are difficult to define, as they vary with the chemical and physical form of lead, exposure regime, other elements present and also vary both within and between species. The technological capability to accurately quantify low lead concentrations has increased over the last decade, and physiological and behavioral effects have been measured in wildlife with tissue lead concentrations below those previously considered safe for humans.s.236 Consequently. lead criteria for the protection of wildlife and human health are frequently under review, and 'thresholds' of lead toxicity are being reconsidered. Proposed lead criteria for the protection of natural resources have been reviewed by Eisler. Uptake of lead by plants is limited by its generally low availability in soils and sediments, and toxicity may be limited by storage mechanisms and its apparently limited translocation within most plants. Lead does not generally accumulate within the foliar parts of plants, which limits its transfer to higher trophic levels. Although lead may concentrate in plant and animal tissues, no evidence of biomagnification exists. Acid deposition onto surface waters and soils with low buffering capacity may influence the availability of lead for uptake by plants and animals, and this may merit investigation at susceptible sites. The biological significance of chronic low-level lead exposure to wildlife is sometimes difficult to quantify. Animals living in urban environments or near point sources of lead emission are inevitably subject to greater exposure to lead and enhanced risk of lead poisoning. Increasingly strict controls on lead emissions in many countries have reduced exposure to lead from some sources
Comparison of electrochemical performance of as-cast Pb-1 wt.% Sn and Pb-1 wt.% Sb alloys for lead-acid battery components

Energy Technology Data Exchange (ETDEWEB)

Osorio, Wislei R.; Peixoto, Leandro C.; Garcia, Amauri [Department of Materials Engineering, University of Campinas - UNICAMP, PO Box 612, 13083-970 Campinas, SP (Brazil)

2010-03-15

A comparative experimental study of the electrochemical features of as-cast Pb-1 wt.% Sn and Pb-1 wt.% Sb alloys is carried out with a view to applications in the manufacture of lead-acid battery components. The as-cast samples are obtained using a water-cooled unidirectional solidification system. Pb-Sn and Pb-Sb alloy samples having similar coarse cell arrays are subjected to corrosion tests in order to assess the effect of Sn or Sb segregation in the cell boundary on the electrochemical performance. Electrochemical impedance spectroscopy (EIS) diagrams, potentiodynamic polarization curves and an equivalent circuit analysis are used to evaluate the electrochemical parameters in a 0.5 M H{sub 2}SO{sub 4} solution at 25 C. Both the experimental and simulated EIS parameters evidence different kinetics of corrosion. The Pb-1 wt.% Sn alloy is found to have a current density which is of about three times lower than that of the Pb-1 wt.% Sb alloy which indicates that dilute Pb-Sn alloys have higher potential for application as positive grid material in maintenance-free Pb-acid batteries. (author)
Effects of Indole-3-Acetic Acid on Germination in Lead Polluted Petri Dish of Citrullus lanatus (Thunberg Matsumura and Nakai, Cucurbitaceae

Directory of Open Access Journals (Sweden)

Matthew Chidozie Ogwu

2015-12-01

Full Text Available Watermelon, Citrullus lanatus (Thunberg Matsumura and Nakai is a tropical fruit vegetable. Indole-3-acetic acid (IAA is a popular phytohormone while lead (Pb is a common environmental pollutant in urban and sub-urban centers. C. lanatus were obtained from Benin City with a view to study the effects of IAA on their germination in Pb polluted environment. Germination percentage without IAA and Pb treatment in petri dish was significant after ten days. Hastened germination was observed when IAA and lead were used. About 100 % germination was recorded after seven days. This suggests that water melon seeds can initiate growth even in lead polluted environment. Optimum level of 5 ppm IAA with the different levels of lead treatments may be recommended. Most important was that higher concentrations of Pb in the control (without IAA did not inhibit seedling shoot nor root growth. Longest seedling shoot length (cm was 10.33 ± 1.24 and 12.13 ± 2.06 on the seventh and eighth day respectively with the combined treatment levels of 1 ppm IAA and 15 ppm Pb. On the ninth day, 15.27 ± 0.96 was obtained from 1 ppm IAA and 20 ppm Pb. Longest seedling root length (cm values were recorded from the combined treatment levels of 0 ppm IAA and 10 ppm Pb for the seventh (9.10 ± 0.47 and ninth (10.37 ± 1.81 day respectively and 0 ppm and 15 ppm Pb on the eighth (9.37 ± 0.84 day. Significant means were also obtained with the treatment level of 0 and 20 ppm IAA. This present study suggest the germination of C. lanatus under Pb polluted environment may be rescued with optimum IAA.
Influence of Heavy Metal Powders on Rheological Properties of Poly(Lactic Acid)

Science.gov (United States)

Lebedev, S. M.; Gefle, O. S.; Amitov, E. T.; Berchuk, D. Yu.; Zhuravlev, D. V.

2017-08-01

Main properties of poly(lactic acid) (PLA) and composite materials on its basis filled with tungsten and lead powders are investigated. An anomalous decrease of the viscosity of melts of poly(lactic acid)/tungsten and poly(lactic acid)/lead composites is detected. The methods of differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and IR spectroscopy are used for investigation. It is shown that the temperature at which the composites filled with tungsten and lead begin to melt decreases by more than 8 and 3°C in comparison with neat PLA. Our investigations show impossibility of preparing radiation resistant polymer composites based on PLA filled with tungsten and lead powders.
Activation by insulin and amino acids of signaling components leading to translation initiation in skeletal muscle of neonatal pigs is developmentally regulated.

Science.gov (United States)

Suryawan, Agus; Orellana, Renan A; Nguyen, Hanh V; Jeyapalan, Asumthia S; Fleming, Jillian R; Davis, Teresa A

2007-12-01

Insulin and amino acids act independently to stimulate protein synthesis in skeletal muscle of neonatal pigs, and the responses decrease with development. The purpose of this study was to compare the separate effects of fed levels of INS and AA on the activation of signaling components leading to translation initiation and how these responses change with development. Overnight-fasted 6- (n = 4/group) and 26-day-old (n = 6/ group) pigs were studied during 1) euinsulinemic-euglycemiceuaminoacidemic conditions (controls), 2) euinsulinemic-euglycemichyperaminoacidemic clamps (AA), and 3) hyperinsulinemic-euglycemic-euaminoacidemic clamps (INS). INS, but not AA, increased the phosphorylation of protein kinase B (PKB) and tuberous sclerosis 2 (TSC2). Both INS and AA increased protein synthesis and the phosphorylation of mammalian target of rapamycin (mTOR), ribosomal protein S6 kinase-1, and eukaryotic initiation factor (eIF)4E-binding protein 1 (4E-BP1), and these responses were higher in 6-day-old compared with 26-day-old pigs. Both INS and AA decreased the binding of 4E-BP1 to eIF4E and increased eIF4E binding to eIF4G; these effects were greater in 6-day-old than in 26-day-old pigs. Neither INS nor AA altered the composition of mTORC1 (raptor, mTOR, and GbetaL) or mTORC2 (rictor, mTOR, and GbetaL) complexes. Furthermore, neither INS, AA, nor age had any effect on the abundance of Rheb and the phosphorylation of AMP-activated protein kinase and eukaryotic elongation factor 2. Our results suggest that the activation by insulin and amino acids of signaling components leading to translation initiation is developmentally regulated and parallels the developmental decline in protein synthesis in skeletal muscle of neonatal pigs.
Resolution in QCM Sensors for the Viscosity and Density of Liquids: Application to Lead Acid Batteries

Directory of Open Access Journals (Sweden)

Jorge Marcos-Acevedo

2012-08-01

Full Text Available In battery applications, particularly in automobiles, submarines and remote communications, the state of charge (SoC is needed in order to manage batteries efficiently. The most widely used physical parameter for this is electrolyte density. However, there is greater dependency between electrolyte viscosity and SoC than that seen for density and SoC. This paper presents a Quartz Crystal Microbalance (QCM sensor for electrolyte density-viscosity product measurements in lead acid batteries. The sensor is calibrated in H₂SO₄ solutions in the battery electrolyte range to obtain sensitivity, noise and resolution. Also, real-time tests of charge and discharge are conducted placing the quartz crystal inside the battery. At the same time, the present theoretical “resolution limit” to measure the square root of the density-viscosity product ( of a liquid medium or best resolution achievable with a QCM oscillator is determined. Findings show that the resolution limit only depends on the characteristics of the liquid to be studied and not on frequency. The QCM resolution limit for measurements worsens when the density-viscosity product of the liquid is increased, but it cannot be improved by elevating the work frequency.
A review of fractional-order techniques applied to lithium-ion batteries, lead-acid batteries, and supercapacitors

Science.gov (United States)

Zou, Changfu; Zhang, Lei; Hu, Xiaosong; Wang, Zhenpo; Wik, Torsten; Pecht, Michael

2018-06-01

Electrochemical energy storage systems play an important role in diverse applications, such as electrified transportation and integration of renewable energy with the electrical grid. To facilitate model-based management for extracting full system potentials, proper mathematical models are imperative. Due to extra degrees of freedom brought by differentiation derivatives, fractional-order models may be able to better describe the dynamic behaviors of electrochemical systems. This paper provides a critical overview of fractional-order techniques for managing lithium-ion batteries, lead-acid batteries, and supercapacitors. Starting with the basic concepts and technical tools from fractional-order calculus, the modeling principles for these energy systems are presented by identifying disperse dynamic processes and using electrochemical impedance spectroscopy. Available battery/supercapacitor models are comprehensively reviewed, and the advantages of fractional types are discussed. Two case studies demonstrate the accuracy and computational efficiency of fractional-order models. These models offer 15-30% higher accuracy than their integer-order analogues, but have reasonable complexity. Consequently, fractional-order models can be good candidates for the development of advanced battery/supercapacitor management systems. Finally, the main technical challenges facing electrochemical energy storage system modeling, state estimation, and control in the fractional-order domain, as well as future research directions, are highlighted.
Association of Lead Levels and Cerebral Palsy

Science.gov (United States)

Bansal, Neha; Aggarwal, Anju; Faridi, M. M. A.; Sharma, Tusha; Baneerjee, B. D.

2017-01-01

Background: Cerebral palsy is a common motor disability in childhood. Raised lead levels affect cognition. Children with cerebral palsy may have raised lead levels, further impairing their residual cognitive motor and behavioral abilities. Environmental exposure and abnormal eating habits may lead to increased lead levels. Aims and Objectives: To measure blood lead levels in children with cerebral palsy and compare them with healthy neurologically normal children. To correlate blood lead levels with environmental factors. Material and Methods: Design: Prospective case-control study. Setting: Tertiary care hospital. Participants: Cases comprised 34 children with cerebral palsy, and controls comprised 34 neurologically normal, age- and sex-matched children. Methods: Clinical and demographic details were recorded as per proforma. Detailed environmental history was recorded to know the source of exposure to lead. These children were investigated and treated as per protocol. Venous blood was collected in ethylenediaminetetraacetic acid vials for analysis of blood lead levels. Lead levels were estimated by Schimadzu Flame AA-6800 (atomic absorption spectrophotometer). Data were analyzed using SPSS version 17. P pica were 12.33 ± 10.02 µg/dL in comparison to children with no history of pica, 6.70 ± 4.60 µg/dL (P = .029). No correlation was found between hemoglobin and blood lead levels in cases and controls. Conclusion: In our study, blood lead levels are raised in children with cerebral palsy. However, further studies are required to show effects of raised levels in these children. PMID:28491920
Sensitivity of in vivo X-ray fluorescence determination of skeletal lead stores

International Nuclear Information System (INIS)

Sokas, R.K.; Besarab, A.; McDiarmid, M.A.; Shapiro, I.M.; Bloch, P.

1990-01-01

Eighteen patients with known past occupational lead exposure underwent parenteral diagnostic chelation with ethylenediaminetetraacetic acid and x-ray fluorescent determination of in vivo skeletal lead stores at the distal styloid process of the ulna and at the temporal base bone using a cobalt 57 source and measuring lead Ka x-rays. X-ray fluorescent lead measurements in both locations correlated with results of diagnostic chelation. Using a post-chelation urinary excretion of greater than 600 micrograms lead/24 h as the definition of high-lead stores, sensitivity of x-ray fluorescence at the wrist and temple was 56% and 39%, respectively
Temperature controlled formation of lead/acid batteries

Science.gov (United States)

Bungardt, M.

At present, standard formation programs have to accommodate the worst case. This is important, especially in respect of variations in climatic conditions. The standard must be set so that during the hottest weather periods the maximum electrolyte temperature is not exceeded. As this value is defined not only by the desired properties and the recipe of the active mass, but also by type and size of the separators and by the dimensions of the plates, general rules cannot be formulated. It is considered to be advantageous to introduce limiting data for the maximum temperature into a general formation program. The latter is defined so that under normal to good ambient conditions the shortest formation time is achieved. If required, the temperature control will reduce the currents employed in the different steps, according to need, and will extend the formation time accordingly. With computer-controlled formation, these parameters can be readily adjusted to suit each type of battery and can also be reset according to modifications in the preceding processing steps. Such a procedure ensures that: (i) the formation time is minimum under the given ambient conditions; (ii) in the event of malpractice ( e.g. actual program not fitting to size) the batteries will not be destroyed; (iii) the energy consumption is minimized (note, high electrolyte temperature leads to excess gassing). These features are incorporated in the BA/FOS-500 battery formation system developed by Digatron. The operational characteristics of this system are listed in Table 1.
Quantification of free sialic acid in urine by HPLC-electrospray tandem mass spectrometry: A tool for the diagnosis of sialic acid storage disease

NARCIS (Netherlands)

Valianpour, Fredoen; Abeling, Nicolaas G. G. M.; Duran, Marinus; Huijmans, Jan G. M.; Kulik, Willem

2004-01-01

Background: Sialic acid storage diseases (SSDs) are severe autosomal recessive neurodegenerative disorders caused by a transport defect across the lysosomal membrane, which leads to accumulation of sialic acid in tissues, fibroblasts, and urine. Defective free sialic acid transport can be
Lead discovery for mammalian elongation of long chain fatty acids family 6 using a combination of high-throughput fluorescent-based assay and RapidFire mass spectrometry assay

International Nuclear Information System (INIS)

Takamiya, Mari; Sakurai, Masaaki; Teranishi, Fumie; Ikeda, Tomoko; Kamiyama, Tsutomu; Asai, Akira

2016-01-01

A high-throughput RapidFire mass spectrometry assay is described for elongation of very long-chain fatty acids family 6 (Elovl6). Elovl6 is a microsomal enzyme that regulates the elongation of C12-16 saturated and monounsaturated fatty acids. Elovl6 may be a new therapeutic target for fat metabolism disorders such as obesity, type 2 diabetes, and nonalcoholic steatohepatitis. To identify new Elovl6 inhibitors, we developed a high-throughput fluorescence screening assay in 1536-well format. However, a number of false positives caused by fluorescent interference have been identified. To pick up the real active compounds among the primary hits from the fluorescence assay, we developed a RapidFire mass spectrometry assay and a conventional radioisotope assay. These assays have the advantage of detecting the main products directly without using fluorescent-labeled substrates. As a result, 276 compounds (30%) of the primary hits (921 compounds) in a fluorescence ultra-high-throughput screening method were identified as common active compounds in these two assays. It is concluded that both methods are very effective to eliminate false positives. Compared with the radioisotope method using an expensive 14 C-labeled substrate, the RapidFire mass spectrometry method using unlabeled substrates is a high-accuracy, high-throughput method. In addition, some of the hit compounds selected from the screening inhibited cellular fatty acid elongation in HEK293 cells expressing Elovl6 transiently. This result suggests that these compounds may be promising lead candidates for therapeutic drugs. Ultra-high-throughput fluorescence screening followed by a RapidFire mass spectrometry assay was a suitable strategy for lead discovery against Elovl6. - Highlights: • A novel assay for elongation of very-long-chain fatty acids 6 (Elovl6) is proposed. • RapidFire mass spectrometry (RF-MS) assay is useful to select real screening hits. • RF-MS assay is proved to be beneficial because of
[Lead intoxication in a group of workers in Germany].

Science.gov (United States)

Willi, R F; Felgenhauer, N; Eyer, F; Buters, J T; Zilker, T

2009-12-01

Seventeen East-European workers with a suspected lead-intoxication presented themselves to the Department of Toxicology. All of them had worked on the renovation of pylons of a high-tension line. The old paint, known to contain lead was removed with needle descalers. The patients had blood lead concentrations between 325 and 1124 microg/l, but no specific symptoms. The workers neglected the protective measures at their working-place. 12 of 17 workers had lead-concentrations above 400 microg/l (Reference lead-concentration above 700 microg/l were treated with the chelating agent meso-2,3-dimercaptosuccinic acid (DMSA) 3 x 200 mg/d for nine days. The patients with lead concentrations between 400 and 700 microg/l were treated which DMSA 3 x 100 mg/d. After the DMSA-treatment the lead-concentrations had dropped (p lead concentration in their blood due to occupational exposure. The high blood lead levels showed that the workers had not been protected adequately. This examplifies that occupational lead exposure still occurs, also in Germany. By patients with unspecific symptoms connected with lead exposure a biomonitoring for lead is necessary.
Gene deletion of cytosolic ATP: citrate lyase leads to altered organic acid production in Aspergillus niger

DEFF Research Database (Denmark)

Meijer, Susan Lisette; Nielsen, Michael Lynge; Olsson, Lisbeth

2009-01-01

With the availability of the genome sequence of the filamentous fungus Aspergillus niger, the use of targeted genetic modifications has become feasible. This, together with the fact that A. niger is well established industrially, makes this fungus an attractive micro-organism for creating a cell...... factory platform for production of chemicals. Using molecular biology techniques, this study focused on metabolic engineering of A. niger to manipulate its organic acid production in the direction of succinic acid. The gene target for complete gene deletion was cytosolic ATP: citrate lyase (acl), which...... the acl gene. Additionally, the total amount of organic acids produced in the deletion strain was significantly increased. Genome-scale stoichiometric metabolic model predictions can be used for identifying gene targets. Deletion of the acl led to increased succinic acid production by A. niger....
Analysis of natural radionuclides and lead in foods and diets

International Nuclear Information System (INIS)

Bueno, Luciana

1999-01-01

The main purpose of the present study was to determine the lead-210, polonium-210 and lead concentrations in foods and diets. Consumption of food is generally the main route by which radionuclides can enter the human organism. Precision and accuracy of the methods developed were verifies by the analysis of reference materials from the International Atomic Energy Agency (IAEA). The method for polonium-210 analysis consisted of sample dissolution by using a microwave digester (open system) employing concentrated nitric acid and hydrogen peroxide, evaporation almost dryness, addition of hydrochloric acid, polonium deposition onto silver disc for six hours and counting by alpha spectrometry. Lead was analysed by atomic absorption technique. After sample dissolution in a microwave digester (using concentrated nitric acid and hydrogen peroxide) and dilution to 50 ml, 20μl of the sample was injected in a pyrolytic graphite furnace - atomic absorption spectrophotometer equipped with Zeeman background correction. The assessment of the contaminants in foods and diets allowed to estimate the intake of these elements and for the radionuclides were also evaluated the radiation doses that the individuals selected were exposed by the food consumption. The effective dose for lead-210 by diets intake ranged from 1.3 to 4.3 μSv/year, corresponding to 25% of the resulting from polonium-210 intake. The dose due to the both natural radionuclides varied from 6.8 to 23.0 μSv/year. These values are in good agreement with the literature data. The value estimated by the United Nations Scientific Committee on Effects of Atomic Radiation (UNSCEAR, 1993) that is 60 μSv and lower than the dose of 0.02 Sv, limit established by ICRP, 1980. The lead levels found in the majority of the Brazilian foods are in good agreement with the values published by CONAT and FAO/WHO. However, some foods such as bean, potato, papaya, apple and rice present levels above of the recommended values by the Public
Effects of a series of acidic drugs on L-lactic acid transport by the monocarboxylate transporters MCT1 and MCT4.

Science.gov (United States)

Leung, Yat Hei; Belanger, Francois; Lu, Jennifer; Turgeon, Jacques; Michaud, Veronique

2018-03-07

Drug-induced myopathy is a serious side effect that often requires removal of a medication from a drug regimen. For most drugs, the underlying mechanism of drug-induced myopathy remains unclear. Monocarboxylate transporters (MCTs) mediate L-lactic acid transport, and inhibition of MCTs may potentially lead to perturbation of L-lactic acid accumulation and muscular disorders. Therefore, we hypothesized that L-lactic acid transport may be involved in the development of drug-induced myopathy. The aim of this study was to assess the inhibitory potential of 24 acidic drugs on L-lactic acid transport using breast cancer cell lines Hs578T and MDA-MB-231, which selectively express MCT1 and MCT4, respectively. The influx transport of L-lactic acid was minimally inhibited by all drugs tested. The efflux transport was next examined: loratadine (IC50: 10 and 61 µM) and atorvastatin (IC50: 78 and 41 µM) demonstrated the greatest potency for inhibition of L-lactic acid efflux by MCT1 and MCT4, respectively. Acidic drugs including fluvastatin, cerivastatin, simvastatin acid, lovastatin acid, irbesartan and losartan exhibited weak inhibitory potency on L-lactic acid efflux. Our results suggest that some acidic drugs, such as loratadine and atorvastatin, can inhibit the efflux transport of L-lactic acid. This inhibition may cause an accumulation of intracellular L-lactic acid leading to acidification and muscular disorders. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
PERSONAL AND ENVIRONMENTAL RISK FACTORS SIGNIFICANTLY ASSOCIATED WITH ELEVATED BLOOD LEAD LEVELS IN RURAL THAI CHILDREN.

Science.gov (United States)

Swaddiwudhipong, Witaya; Kavinum, Suporn; Papwijitsil, Ratchadaporn; Tontiwattanasap, Worawit; Khunyotying, Wanlee; Umpan, Jiraporn; BoonthuM, Ratchaneekorn; Kaewnate, Yingyot; Boonmee, Sasis; Thongchub, Winai; Rodsung, Thassanee

2014-11-01

A community-based study was conducted to determine personal risk factors and environmental sources of lead exposure for elevated blood lead levels (≥ 10 µg/dl, EBLLs) among rural children living at the Thailand-Myanmar border in Tak Province, northwestern Thailand. Six hundred ninety-five children aged 1-14 years old were screened for BLLs. Environmental specimens for lead measurements included samples of water from the streams, taps, and household containers, house floor dust, and foods. Possible lead release from the cooking ware was determined using the leaching method with acetic acid. The overall prevalence of EBLLs was 47.1% and the geometric mean level of blood lead was 9.16 µg/dl. Personal risk factors significantly associated with EBLLs included being male, younger age, anemia, and low weight-for-age. Significant environmental risk factors were exposure to a lead-acid battery of solar energy system and use of a non-certified metal cooking pot. Some families whose children had high BLLs reported production of lead bullets from the used batteries at home. About one-third of the house dust samples taken near batteries contained lead content above the recommended value, compared with none of those taken from other areas and from the houses with no batteries. The metal pots were safe for cooking rice but might be unsafe for acidic food preparation. Both nutritional intervention and lead exposure prevention programs are essential to reduce EBLLs in this population.

Lead evaluation in blood of workers of batteries industries

International Nuclear Information System (INIS)

Valbuena P, John J; Duarte, Martha; Marciales Clara

2001-01-01

In order to evaluate the occupational risk of exposure to lead of employees working in three small industries that recycle and manufacture acid lead batteries, the lead and zinc protoporphyrine (ZPP) blood content was determined. The determination was also performed on people not exposed in order to establish comparison values. Venous blood was collected in metal free heparinized glass tubes. Lead was analyzed by atomic absorption with graphite furnace and ZPP by fluorescence. According to Colombian legislation, it was found that around 31 % workers in this type of industries are in dangerous and intoxication exposure. It was also found that 91 % of workers exceed the level of 30 mg Pb/dL blood established as standard by the American Conference governmental Industrial Hygienists (ACGIH)
Galvanic Corrosion of Lead by Iron (Oxyhydr)Oxides: Potential Impacts on Drinking Water Quality.

Science.gov (United States)

Trueman, Benjamin F; Sweet, Gregory A; Harding, Matthew D; Estabrook, Hayden; Bishop, D Paul; Gagnon, Graham A

2017-06-20

Lead exposure via drinking water remains a significant public health risk; this study explored the potential effects of upstream iron corrosion on lead mobility in water distribution systems. Specifically, galvanic corrosion of lead by iron (oxyhydr)oxides was investigated. Coupling an iron mineral cathode with metallic lead in a galvanic cell increased lead release by 531 μg L -1 on average-a 9-fold increase over uniform corrosion in the absence of iron. Cathodes were composed of spark plasma sintered Fe 3 O 4 or α-Fe 2 O 3 or field-extracted Fe 3 O 4 and α-FeOOH. Orthophosphate immobilized oxidized lead as insoluble hydroxypyromorphite, while humic acid enhanced lead mobility. Addition of a humic isolate increased lead release due to uniform corrosion by 81 μg L -1 and-upon coupling lead to a mineral cathode-release due to galvanic corrosion by 990 μg L -1 . Elevated lead in the presence of humic acid appeared to be driven by complexation, with 208 Pb and UV 254 size-exclusion chromatograms exhibiting strong correlation under these conditions (R 2 average = 0.87). A significant iron corrosion effect was consistent with field data: lead levels after lead service line replacement were greater by factors of 2.3-4.7 at sites supplied by unlined cast iron distribution mains compared with the alternative, lined ductile iron.
Lead poisoning from drinking Kombucha tea brewed in a ceramic pot.

Science.gov (United States)

Phan, T G; Estell, J; Duggin, G; Beer, I; Smith, D; Ferson, M J

Kombucha tea is an alternative therapy that is gaining popularity as a remedy for a diverse range of ailments. We report two cases of symptomatic lead poisoning requiring chelation therapy in a married couple who had been drinking Kombucha tea for six months, brewing the tea in a ceramic pot. We postulate that acids in the tea eluted lead from the glaze pigment used in the ceramic pot, in a manner analogous to elution of lead from crystal decanters by wine and spirits.
78 FR 63148 - Approval and Promulgation of Implementation Plans; Tennessee; Bristol; 2010 Lead Base Year...

Science.gov (United States)

2013-10-23

... Tennessee, through the Tennessee Department of Environment and Conservation (TDEC) on April 11, 2013. The... per year within the Bristol Area is Exide Technologies Facility, a lead acid battery manufacturing and recycling facility which processes lead and reclaimed lead into batteries for the auto industry. Pursuant to...
Containing arsenic-enriched groundwater tracing lead isotopic compositions of common arsenical pesticides in a coastal Maine watershed

Science.gov (United States)

Ayuso, Robert A.; Foley, Nora K.; Robinson, Glipin R.; Colvin, A.S.; Lipfert, G.; Reeve, A.S.

2006-01-01

Arsenical pesticides and herbicides were extensively used on apple, blueberry, and potato crops in New England during the first half of the twentieth century. Lead arsenate was the most heavily used arsenical pesticide until it was officially banned. Lead arsenate, calcium arsenate, and sodium arsenate have similar Pb isotope compositions: 208Pb207Pb = 2.3839-2.4722, and 206Pb207Pb = 1.1035-1.2010. Other arsenical pesticides such as copper acetoarsenite (Paris green), methyl arsonic acid and methane arsonic acid, as well as arsanilic acid are widely variable in isotope composition. Although a complete understanding of the effects of historical use of arsenical pesticides is not available, initial studies indicate that arsenic and lead concentrations in stream sediments in New England are higher in agricultural areas that intensely used arsenical pesticides than in other areas. The Pb isotope compositions of pesticides partially overlap values of stream sediments from areas with the most extensive agricultural use. The lingering effects of arsenical pesticide use were tested in a detailed geochemical and isotopic study of soil profiles from a watershed containing arsenic-enriched ground water in coastal Maine. Acid-leach compositions of the soils represent lead adsorbed to mineral surfaces or held in soluble minerals (Fe- and Mn-hydroxides, carbonate, and some micaceous minerals), whereas residue compositions likely reflect bedrock compositions. The soil profiles contain labile Pb (acid-leach) showing a moderate range in 206Pb 207Pb (1.1870-1.2069), and 208Pb207Pb (2.4519-2.4876). Isotope values vary as a function of depth: the lowest Pb isotope ratios (e.g.,208Pb206Pb) representing labile lead are in the uppermost soil horizons. Lead contents decrease with depth in the soil profiles. Arsenic contents show no clear trend with depth. A multi-component mixing scheme that included lead from the local parent rock (Penobscot Formation), lead derived from combustion of
VRLA Refined™ lead — A must for VRLA batteries. Specification and Performance

Science.gov (United States)

Stevenson, M. W.; Lakshmi, C. S.; Manders, J. E.; Lam, L. T.

VRLA Refined™ lead produced and marketed by Pasminco since 1997 is a very high purity lead with guaranteed low levels of the gassing elements but with optimum bismuth content that produces oxide of finer particle size, higher acid absorption and imparts outstanding electrical performance and endurance especially under conditions of deep cycling. VRLA batteries suffer dry-out, self-discharge, negative plate capacity loss and poor cycle life unless special lead is used for the grids and active material. This paper addresses the lead used for active material.
Changes in actin dynamics are involved in salicylic acid signaling pathway.

Science.gov (United States)

Matoušková, Jindřiška; Janda, Martin; Fišer, Radovan; Sašek, Vladimír; Kocourková, Daniela; Burketová, Lenka; Dušková, Jiřina; Martinec, Jan; Valentová, Olga

2014-06-01

Changes in actin cytoskeleton dynamics are one of the crucial players in many physiological as well as non-physiological processes in plant cells. Positioning of actin filament arrays is necessary for successful establishment of primary lines of defense toward pathogen attack, depolymerization leads very often to the enhanced susceptibility to the invading pathogen. On the other hand it was also shown that the disruption of actin cytoskeleton leads to the induction of defense response leading to the expression of PATHOGENESIS RELATED proteins (PR). In this study we show that pharmacological actin depolymerization leads to the specific induction of genes in salicylic acid pathway but not that involved in jasmonic acid signaling. Life imaging of leafs of Arabidopsis thaliana with GFP-tagged fimbrin (GFP-fABD2) treated with 1 mM salicylic acid revealed rapid disruption of actin filaments resembling the pattern viewed after treatment with 200 nM latrunculin B. The effect of salicylic acid on actin filament fragmentation was prevented by exogenous addition of phosphatidic acid, which binds to the capping protein and thus promotes actin polymerization. The quantitative evaluation of actin filament dynamics is also presented. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Production of arachidonic and linoleic acid metabolites by guinea pig tracheal epithelial cells

International Nuclear Information System (INIS)

Oosthuizen, M.J.; Engels, F.; Van Esch, B.; Henricks, P.A.; Nijkamp, F.P.

1990-01-01

Pulmonary epithelial cells may be responsible for regulating airway smooth muscle function, in part by release of fatty acid-derived mediators. Incubation of isolated guinea pig tracheal epithelial cells with radiolabeled arachidonic acid (AA) leads to the production of 5- and 15-hydroxyeicosatetraenoic acid (5- and 15-HETE) and smaller amounts of leukotriene (LT) B4 and C4 and 12-hydroxyheptadecatrienoic acid (HHT). Epithelial cells also are able to release linoleic acid (LA) metabolites. Incubation with radiolabeled linoleic acid leads to the formation of 9- and 13-hydroxyoctadecadienoic acid (9- and 13-HODE). The biological significance of these mediators produced by epithelial cells is discussed
Azetidinic amino acids

DEFF Research Database (Denmark)

Bräuner-Osborne, Hans; Bunch, Lennart; Chopin, Nathalie

2005-01-01

A set of ten azetidinic amino acids, that can be envisioned as C-4 alkyl substituted analogues of trans-2-carboxyazetidine-3-acetic acid (t-CAA) and/or conformationally constrained analogues of (R)- or (S)-glutamic acid (Glu) have been synthesized in a diastereo- and enantiomerically pure form from...... of two diastereoisomers that were easily separated and converted in two steps into azetidinic amino acids. Azetidines 35-44 were characterized in binding studies on native ionotropic Glu receptors and in functional assays at cloned metabotropic receptors mGluR1, 2 and 4, representing group I, II and III...... beta-amino alcohols through a straightforward five step sequence. The key step of this synthesis is an original anionic 4-exo-tet ring closure that forms the azetidine ring upon an intramolecular Michael addition. This reaction was proven to be reversible and to lead to a thermodynamic distribution...
Impact of scaling on the nitric-glycolic acid flowsheet

Energy Technology Data Exchange (ETDEWEB)

Lambert, D. [Savannah River Site (SRS), Aiken, SC (United States)

2016-02-01

Savannah River Remediation (SRR) is considering using glycolic acid as a replacement for formic acid in Sludge Receipt and Adjustment Tank (SRAT) processing in the Defense Waste Processing Facility (DWPF). Catalytic decomposition of formic acid is responsible for the generation of hydrogen, a potentially flammable gas, during processing. To prevent the formation of a flammable mixture in the offgas, an air purge is used to dilute the hydrogen concentration below the 60% of the Composite Lower Flammability Limit (CLFL). The offgas is continuously monitored for hydrogen using Gas Chromatographs (GCs). Since formic acid is much more volatile and toxic than glycolic acid, a formic acid spill would lead to the release of much larger quantities to the environment. Switching from formic acid to glycolic acid is expected to eliminate the hydrogen flammability hazard leading to lower air purges, thus downgrading of Safety Significant GCs to Process Support GCs, and minimizing the consequence of a glycolic acid tank leak in DWPF. Overall this leads to a reduction in process operation costs and an increase in safety margin. Experiments were completed at three different scales to demonstrate that the nitric-glycolic acid flowsheet scales from the 4-L lab scale to the 22-L bench scale and 220-L engineering scale. Ten process demonstrations of the sludge-only flowsheet for SRAT and Slurry Mix Evaporator (SME) cycles were performed using Sludge Batch 8 (SB8)-Tank 40 simulant. No Actinide Removal Process (ARP) product or strip effluent was added during the runs. Six experiments were completed at the 4-L scale, two experiments were completed at the 22-L scale, and two experiments were completed at the 220-L scale. Experiments completed at the 4-L scale (100 and 110% acid stoichiometry) were repeated at the 22-L and 220-L scale for scale comparisons.
The preparation of a novel layered lead titanate and its conversion to the perovskite lead titanate PbTiO3

NARCIS (Netherlands)

Blake, G.R.; Armstrong, A.R.; Sastre, E.; Wright, P.A.

2001-01-01

A novel layered lead titanate with the approximate composition PbTiO2(CO3)0.3(NO3)0.35(OH) has been synthesized hydrothermally under acidic conditions. The structure has been solved and refined from X-ray and neutron powder diffraction data in the space group P -3 1 m, with cell dimensions a =
Imidazole-4-acetic acid, a new lead structure for interaction with the taurine transporter in outer blood-retinal barrier cells.

Science.gov (United States)

Valembois, Sophie; Krall, Jacob; Frølund, Bente; Steffansen, Bente

2017-05-30

Retinal diseases leading to impaired vision and ultimately blindness are mainly characterized by ischemic and hypoxic stress. Targeting the retinal ρ-containing γ-aminobutyric acid type A receptors (ρ GABA A Rs) and thereby decreasing the retinal neuronal activity has been proposed as a novel therapeutic approach. The taurine transporter (TAUT) plays a key role in the retinal transport of GABA and has been previously suggested to display a higher functional activity in the retina compared to the brain. TAUT would therefore stand as a suitable target for the selective delivery of ρ GABA A R ligands into the retina. Consequently, an in vitro model of TAUT at the outer blood-retinal barrier (BRB) was developed and characterized using the ARPE-19 cell line. Furthermore, the structural requirements of GABA A R ligands for interacting with TAUT at the BRB were investigated for a series of standard GABA A R ligands by testing their ability to inhibit the TAUT-mediated influx of taurine in ARPE-19 cells. Results showed that taurine influx was seven-fold higher when the ARPE-19 cells were cultured under hyperosmotic conditions and was demonstrated to display saturable kinetics (K m =27.7±2.2μM and J max =24.2±0.6pmol/cm 2 ·min). Furthermore, the taurine influx was significantly inhibited in a concentration-dependent manner by GABA and imidazole-4-acetic acid (IAA), which is a naturally occurring metabolite of histamine. These compounds display similar K i values of 644.2μM and 658.6μM, respectively. Moreover, IAA demonstrated higher inhibitory properties than the other tested GABA analogs: 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP), 4,5,6,7-tetrahydropyrazolo[5,4-c]pyridin-3-ol (Aza-THIP), muscimol, and thiomuscimol. These studies demonstrated that IAA interacts with TAUT, which makes IAA a new lead structure in the development of new compounds, which are not only interacting with TAUT but also potent ρ GABA A R ligands. Copyright © 2017 Elsevier B
Unusual Amino Acids in Medicinal Chemistry.

Science.gov (United States)

Blaskovich, Mark A T

2016-12-22

Unusual amino acids are fundamental building blocks of modern medicinal chemistry. The combination of readily functionalized amine and carboxyl groups attached to a chiral central core along with one or two potentially diverse side chains provides a unique three-dimensional structure with a high degree of functionality. This makes them invaluable as starting materials for syntheses of complex molecules, highly diverse elements for SAR campaigns, integral components of peptidomimetic drugs, and potential drugs on their own. This Perspective highlights the diversity of unnatural amino acid structures found in hit-to-lead and lead optimization campaigns and clinical stage and approved drugs, reflecting their increasingly important role in medicinal chemistry.
Identification of intermediates leading to chloroform and C-4 diacids in the chlorination of humic acid

NARCIS (Netherlands)

Sinninghe Damsté, J.S.; Leer, E.W.B. de; Erkelens, Corrie; Galan, L.

1985-01-01

The chlorination of terrestrial humic acid was studied at pH 7. 2 with varying chlorine to carbon ratios. The principal products are chloroform, di- and trichloroacetic acid, and chlorinated C-4 diacids. At a high chlorine dose many new chlorination products were detected, among them
Modeling the effect of succimer (DMSA; dimercaptosuccinic acid) chelation therapy in patients poisoned by lead

NARCIS (Netherlands)

van Eijkeren, Jan C H; Olie, J. Daniël N; Bradberry, Sally M; Vale, J Allister; de Vries, Irma; Clewell, Harvey J.; Meulenbelt, Jan; Hunault, Claudine C

CONTEXT: Kinetic models could assist clinicians potentially in managing cases of lead poisoning. Several models exist that can simulate lead kinetics but none of them can predict the effect of chelation in lead poisoning. Our aim was to devise a model to predict the effect of succimer
Multicollinearity may lead to artificial interaction: an example from a cross sectional study of biomarkers.

Science.gov (United States)

Sithisarankul, P; Weaver, V M; Diener-West, M; Strickland, P T

1997-06-01

Collinearity is the situation which arises in multiple regression when some or all of the explanatory variables are so highly correlated with one another that it becomes very difficult, if not impossible, to disentangle their influences and obtain a reasonably precise estimate of their effects. Suppressor variable is one of the extreme situations of collinearity that one variable can substantially increase the multiple correlation when combined with a variable that is only modestly correlated with the response variable. In this study, we describe the process by which we disentangled and discovered multicollinearity and its consequences, namely artificial interaction, using the data from cross-sectional quantification of several biomarkers. We showed how the collinearity between one biomarker (blood lead level) and another (urinary trans, trans-muconic acid) and their interaction (blood lead level* urinary trans, trans-muconic acid) can lead to the observed artificial interaction on the third biomarker (urinary 5-aminolevulinic acid).
Water solubilization and the dielectric permeability of isomolar solutions of oleic acid and triethanolamine soap of oleic acid

Energy Technology Data Exchange (ETDEWEB)

Demchenko, P.A.; Novitskaya, L.D.

The investigation of the dependence of water solubilization on the dielectric permeability of isomolar solutions of oleic acid and triethanolamine soap of oleic acid in benzene has shown that at certain acid additions, the solubilization effect can increase almost 6 times, as compared to the soap solution without acid additions. In some cases, electron donor-acceptor complexes are formed, which are more polar than the original components. This leads to a change in the molecular-disperse and micellar part of solution and affects significantly the structure and properties of micellar hydrocarbon solutions of surfactants.
Production of Odd-Carbon Dicarboxylic Acids in Escherichia coli Using an Engineered Biotin-Fatty Acid Biosynthetic Pathway.

Science.gov (United States)

Haushalter, Robert W; Phelan, Ryan M; Hoh, Kristina M; Su, Cindy; Wang, George; Baidoo, Edward E K; Keasling, Jay D

2017-04-05

Dicarboxylic acids are commodity chemicals used in the production of plastics, polyesters, nylons, fragrances, and medications. Bio-based routes to dicarboxylic acids are gaining attention due to environmental concerns about petroleum-based production of these compounds. Some industrial applications require dicarboxylic acids with specific carbon chain lengths, including odd-carbon species. Biosynthetic pathways involving cytochrome P450-catalyzed oxidation of fatty acids in yeast and bacteria have been reported, but these systems produce almost exclusively even-carbon species. Here we report a novel pathway to odd-carbon dicarboxylic acids directly from glucose in Escherichia coli by employing an engineered pathway combining enzymes from biotin and fatty acid synthesis. Optimization of the pathway will lead to industrial strains for the production of valuable odd-carbon diacids.
Determination of Lead in Blood by Atomic Absorption Spectrophotometry1

Science.gov (United States)

Selander, Stig; Cramér, Kim

1968-01-01

Lead in blood was determined by atomic absorption spectrophotometry, using a wet ashing procedure and a procedure in which the proteins were precipitated with trichloroacetic acid. In both methods the lead was extracted into isobutylmethylketone before measurement, using ammonium pyrrolidine dithiocarbamate as chelator. The simpler precipitation procedure was shown to give results identical with those obtained with the ashing technique. In addition, blood specimens were examined by the precipitation method and by spectral analysis, which method includes wet ashing of the samples, with good agreement. All analyses were done on blood samples from `normal' persons or from lead-exposed workers, and no additions of inorganic lead were made. The relatively simple protein precipitation technique gave accurate results and is suitable for the large-scale control of lead-exposed workers. PMID:5663425
Association of Lead Levels and Cerebral Palsy

Directory of Open Access Journals (Sweden)

Neha Bansal MD

2017-03-01

Full Text Available Background: Cerebral palsy is a common motor disability in childhood. Raised lead levels affect cognition. Children with cerebral palsy may have raised lead levels, further impairing their residual cognitive motor and behavioral abilities. Environmental exposure and abnormal eating habits may lead to increased lead levels. Aims and Objectives: To measure blood lead levels in children with cerebral palsy and compare them with healthy neurologically normal children. To correlate blood lead levels with environmental factors. Material and Methods: Design: Prospective case-control study. Setting: Tertiary care hospital. Participants: Cases comprised 34 children with cerebral palsy, and controls comprised 34 neurologically normal, age- and sex-matched children. Methods: Clinical and demographic details were recorded as per proforma. Detailed environmental history was recorded to know the source of exposure to lead. These children were investigated and treated as per protocol. Venous blood was collected in ethylenediaminetetraacetic acid vials for analysis of blood lead levels. Lead levels were estimated by Schimadzu Flame AA-6800 (atomic absorption spectrophotometer. Data were analyzed using SPSS version 17. P < .05 was taken as significant. Results: Mean blood lead levels were 9.20 ± 8.31 µg/dL in cerebral palsy cases and 2.89 ± 3.04 µg/dL in their controls (P < .001. Among children with cerebral palsy, 19 (55.88% children had blood lead levels ≥5 µg/dL. Lead levels in children with pica were 12.33 ± 10.02 µg/dL in comparison to children with no history of pica, 6.70 ± 4.60 µg/dL (P = .029. No correlation was found between hemoglobin and blood lead levels in cases and controls. Conclusion: In our study, blood lead levels are raised in children with cerebral palsy. However, further studies are required to show effects of raised levels in these children.

[Nonesterified fatty acids and the titrable acidity of breast milk. Consequences for collection conditions in milk bans].

Science.gov (United States)

Luzeau, R; Barrois, V; Odièvre, M

1983-01-01

The study of breast-milk samples, fresh or after storage, shows that the titrable acidity (expressed in degrees Dornic) is directly correlated with their nonesterified fatty acid concentration. Those fresh samples which contain a high activity of lipoprotein lipase can develop in situ lipolysis. The resulting elevated titrable acidity may lead to consider these samples as unsuitable for infant nutrition. These results suggest that collection and storage of breast-milk have to be reassessed in order to avoid in situ lipolysis.
SUNRAYCE 95: Working safely with lead-acid batteries and photovoltaic power systems

Energy Technology Data Exchange (ETDEWEB)

DePhillips, M.P.; Moskowitz, P.D.; Fthenakis, V.M. [Brookhaven National Lab., Upton, NY (United States). Biomedical and Environmental Assessment Group

1994-05-27

This document is a power system and battery safety handbook for participants in the SUNRAYCE 95 solar powered electric vehicle program. The topics of the handbook include batteries, photovoltaic modules, safety equipment needed for working with sulfuric acid electrolyte and batteries, battery transport, accident response, battery recharging and ventilation, electrical risks on-board vehicle, external electrical risks, electrical risk management strategies, and general maintenance including troubleshooting, hydrometer check and voltmeter check.
Lead exposure and biological effects in pied flycatchers (Ficedula hypoleuca) before and after the closure of a lead mine in northern Sweden

International Nuclear Information System (INIS)

Berglund, A.M.M.; Ingvarsson, P.K.; Danielsson, H.; Nyholm, N.E.I.

2010-01-01

Mining activities affect the surrounding environment by increasing exposure to metals. In this study, metal accumulation and its effects on reproduction and health of pied flycatcher (Ficedula hypoleuca) nestlings were monitored before and up to five years after a lead mine and enrichment plant closed down. The lead concentration in moss, nestling blood, liver and feces all indicated decreased lead exposure by at least 31% after closure, although only blood lead decreased significantly. Although the birds responded fairly well to the changed atmospheric deposition (based on moss samples), concentrations were still higher compared with birds in a reference area, and breeding was affected at the mine (smaller clutches and higher mortality). Surviving nestlings suffered from lower hemoglobin levels, mean cell hemoglobin concentrations and inhibited δ-aminolevulinic acid dehydratase activity. Lead poisoning contributed to poor health and adverse reproductive effects, but other factors (e.g. increased parasitic load) probably also affected the birds. - Increased mortality and lower blood values in pied flycatcher (Ficedula hypoleuca) nestlings near a closed lead mine.
Effect of lead on heme synthesis

Energy Technology Data Exchange (ETDEWEB)

Neuberger, A.

1975-01-01

Recently, a fair amount of work has been done on the effect of lead on porphobilinogen dehydratase, which has been used as a sensitive indicator of lead poisoning. How far this is in itself harmful depends on the Michaelis constants of both the aminolaevulinic synthetase and of the dehydratase, and in addition on the relative activities of the two enzymes in a cell and also on the tissue concentration of glycine. Information on some of these points is still fragmentary, and a reliable judgement is at the present not very easy. Another step in the heme synthesis, which is sensitive to low concentrations of lead, is the incorporation of iron into protoporphyrin. Inhibition of this step may be important in accounting to a large extent for the anaemia found in individuals with lead poisoning. Reduction in the tissue concentration of heme or of heme-like compounds may also explain, through the mechanism of de-repression, the excretion of increased amounts of aminolaevulinic acid in the urine observed in cases of lead poisoning. A third step in heme synthesis, which might be sensitive to lead, is the oxidative decarboxylation of coproporphyrin to protoporphyrin, and this may explain why the former derivative is excreted in the urine. Recent work of the Harvard Medical School has indicated that greatly reduced levels of ALA dehydratase may be found in most cases of severe liver damage due to alcoholism. In most of these cases the level of lead in the blood is within normal limits, and there is no history of exposure to toxic amounts of lead. We therefore have to assume that a reduction in the blood level of this enzyme is not necessarily an indication of lead poisoning.
Occupational health programme for lead workers in battery plants

Science.gov (United States)

Lee, Byung-Kook

The realization of problems resulting from the exposure to undue high lead levels of workers in lead-using industries, particularly in storage battery plants, has given rise to a new occupational health service, the so-called type specific (harmful agent specific) group occupational health. In 1988, the Korean Ministry of Labor designated the Institute of Industrial Medicine, Soonchunhyang University, as an authorized organization to take care of lead workers in lead industries. The following occupational health services are provided by the Institute: (i) physical health examination; (ii) biological monitoring with zinc protoporphyrin, urine δ-aminolevulinic acid and blood lead; (iii) respiratory protection with maintenance-free respirators; (iv) measurement of the environmental condition of workplaces; (v) health education. A three-year occupational health programme for lead workers has contributed to improvements in the working conditions of lead industries, particularly in large-scale battery plants, and has decreased the unnecessary high lead burden of workers through on-going medical surveillance with biological monitoring and health education schemes. The strong commitment of both employers and the government to improve the working conditions of lead industries, together with the full cooperation of lead workers, has served to reduce the high lead burdens of lead workers. This decreases the number of lead-poisoning cases and provides more comfortable workplaces, particularly in battery plants.
Mechanisms leading to oligomers and SOA through aqueous photooxidation: insights from OH radical oxidation of acetic acid and methylglyoxal

Directory of Open Access Journals (Sweden)

Y. Tan

2012-01-01

Full Text Available Previous experiments have demonstrated that the aqueous OH radical oxidation of methylglyoxal produces low volatility products including pyruvate, oxalate and oligomers. These products are found predominantly in the particle phase in the atmosphere, suggesting that methylglyoxal is a precursor of secondary organic aerosol (SOA. Acetic acid plays a central role in the aqueous oxidation of methylglyoxal and it is a ubiquitous product of gas phase photochemistry, making it a potential "aqueous" SOA precursor in its own right. However, the fate of acetic acid upon aqueous-phase oxidation is not well understood. In this research, acetic acid (20 μM–10 mM was oxidized by OH radicals, and pyruvic acid and methylglyoxal experimental samples were analyzed using new analytical methods, in order to better understand the formation of SOA from acetic acid and methylglyoxal. Glyoxylic, glycolic, and oxalic acids formed from acetic acid and OH radicals. In contrast to the aqueous OH radical oxidation of methylglyoxal, the aqueous OH radical oxidation of acetic acid did not produce succinic acid and oligomers. This suggests that the methylgloxal-derived oligomers do not form through the acid catalyzed esterification pathway proposed previously. Using results from these experiments, radical mechanisms responsible for oligomer formation from methylglyoxal oxidation in clouds and wet aerosols are proposed. The importance of acetic acid/acetate as an SOA precursor is also discussed. We hypothesize that this and similar chemistry is central to the daytime formation of oligomers in wet aerosols.
Reaction of acid esters of methylenebis(phosphonous acid) with carbonyl compounds

International Nuclear Information System (INIS)

Novikova, Z.S.; Odinets, I.L.; Lutsenko, I.F.

1987-01-01

The reaction of methylenebis(phosphonites) containing two hydrophosphoryl groupings with aliphatic and aromatic aldehydes and ketones in the presence of alkali metal fluorides leads to methylenebis(α-hydroxyalkylphosphinates). The reaction of methylenebis(phosphonites) containing one hydrophosphoryl groupings with carbonyl compounds in the presence of alkali metal fluorides proceeds with the formation of a new type of heterocyclic phosphorus compound, viz., 1,2λ 3 ,4λ 5 -oxadiphospholanes. The reaction of acid esters of methylenebis(phosphonous) acid with carbonyl compounds in the presence of alkali metal alkoxides or a tertiary amine is accompanied by phosphinate-phosphonate rearrangement of the intermediately formed α-hydroxylalkylphosphinates
Citric acid improves lead (pb) phytoextraction in brassica napus L. by mitigating pb-induced morphological and biochemical damages.

Science.gov (United States)

Shakoor, Muhammad Bilal; Ali, Shafaqat; Hameed, Amjad; Farid, Mujahid; Hussain, Sabir; Yasmeen, Tahira; Najeeb, Ullah; Bharwana, Saima Aslam; Abbasi, Ghulam Hasan

2014-11-01

Phytoextraction is an environmentally friendly and a cost-effective strategy for remediation of heavy metal contaminated soils. However, lower bioavailability of some of the metals in polluted environments e.g. lead (Pb) is a major constraint of phytoextraction process that could be overcome by applying organic chelators. We conducted a glasshouse experiment to evaluate the role of citric acid (CA) in enhancing Pb phytoextraction. Brassica napus L. seedlings were grown in hydroponic media and exposed to various treatments of Pb (50 and 100 μM) as alone or in combination with CA (2.5mM) for six weeks. Pb-induced damage in B. napus toxicity was evident from elevated levels of malondialdehyde (MDA) and H2O2 that significantly inhibited plant growth, biomass accumulation, leaf chlorophyll contents and gas exchange parameters. Alternatively, CA application to Pb-stressed B. napus plants arrested lipid membrane damage by limiting MDA and H2O2 production and by improving antioxidant enzyme activities. In addition, CA significantly increased the Pb accumulation in B. napus plants. The study concludes that CA has a potential to improve Pb phytoextraction without damaging plant growth. Copyright © 2014 Elsevier Inc. All rights reserved.
A field study of lead phytoextraction by various scented Pelargonium cultivars

OpenAIRE

Arshad, Muhammad; Silvestre, Jérôme; Pinelli, Eric; Kallerhoff, Jean; Kaemmerer, Michel; Tarigo, A.; Shahid, Muhammad; Guiresse, Agnès Maritchù; Pradère, Philippe; Dumat, Camille

2008-01-01

Phytoremediation appears to be a promising technique for metal soil clean up, although its successful application on a large scale still remains a challenge. Field experiments for six scented Pelargonium cultivars, conducted on two Pb-contaminated calcareous and acidic soils, revealed vigorous plant growth, with no symptoms of morpho-phytotoxicity in spite of high Pb accumulation levels. Lead contents in the harvestable parts of all plants grown on the acidic and more contaminated soil were s...
Lead exposure from aluminum cookware in Cameroon

International Nuclear Information System (INIS)

Weidenhamer, Jeffrey D.; Kobunski, Peter A.; Kuepouo, Gilbert; Corbin, Rebecca W.; Gottesfeld, Perry

2014-01-01

Blood lead levels have decreased following the removal of lead from gasoline in most of the world. However, numerous recent studies provide evidence that elevated blood lead levels persist in many low and middle-income countries around the world at much higher prevalence than in the more developed countries. One potential source of lead exposure that has not been widely investigated is the leaching of lead from artisanal aluminum cookware, which is commonly used in the developing world. Twenty-nine samples of aluminum cookware and utensils manufactured by local artisans in Cameroon were collected and analyzed for their potential to release lead during cooking. Source materials for this cookware included scrap metal such as engine parts, radiators, cans, and construction materials. The lead content of this cookware is relatively low (< 1000 ppm by X-ray fluorescence), however significant amounts of lead, as well as aluminum and cadmium were released from many of the samples using dilute acetic acid extractions at boiling and ambient temperatures. Potential exposures to lead per serving were estimated to be as high as 260 μg, indicating that such cookware can pose a serious health hazard. We conclude that lead, aluminum and cadmium can migrate from this aluminum cookware during cooking and enter food at levels exceeding recommended public health guidelines. Our results support the need to regulate lead content of materials used to manufacture these pots. Artisanal aluminum cookware may be a major contributor to lead poisoning throughout the developing world. Testing of aluminum cookware in other developing countries is warranted. - Highlights: • Cookware is manufactured in Cameroon from scrap aluminum including car parts. • Twenty-nine cookware samples were evaluated for their potential to leach lead. • Boiling extractions to simulate the effects of cooking released significant lead. • Potential lead exposures per serving are estimated as high as 260 μg. �
Lead exposure from aluminum cookware in Cameroon

Energy Technology Data Exchange (ETDEWEB)

Weidenhamer, Jeffrey D.; Kobunski, Peter A. [Department of Chemistry, Geology and Physics, 401 College Ave., Ashland University, Ashland, OH 44805 (United States); Kuepouo, Gilbert [Research and Education Centre for Development (CREPD), Yaounde (Cameroon); Corbin, Rebecca W. [Department of Chemistry, Geology and Physics, 401 College Ave., Ashland University, Ashland, OH 44805 (United States); Gottesfeld, Perry, E-mail: pgottesfeld@okinternational.org [Occupational Knowledge International, San Francisco, CA (United States)

2014-10-15

Blood lead levels have decreased following the removal of lead from gasoline in most of the world. However, numerous recent studies provide evidence that elevated blood lead levels persist in many low and middle-income countries around the world at much higher prevalence than in the more developed countries. One potential source of lead exposure that has not been widely investigated is the leaching of lead from artisanal aluminum cookware, which is commonly used in the developing world. Twenty-nine samples of aluminum cookware and utensils manufactured by local artisans in Cameroon were collected and analyzed for their potential to release lead during cooking. Source materials for this cookware included scrap metal such as engine parts, radiators, cans, and construction materials. The lead content of this cookware is relatively low (< 1000 ppm by X-ray fluorescence), however significant amounts of lead, as well as aluminum and cadmium were released from many of the samples using dilute acetic acid extractions at boiling and ambient temperatures. Potential exposures to lead per serving were estimated to be as high as 260 μg, indicating that such cookware can pose a serious health hazard. We conclude that lead, aluminum and cadmium can migrate from this aluminum cookware during cooking and enter food at levels exceeding recommended public health guidelines. Our results support the need to regulate lead content of materials used to manufacture these pots. Artisanal aluminum cookware may be a major contributor to lead poisoning throughout the developing world. Testing of aluminum cookware in other developing countries is warranted. - Highlights: • Cookware is manufactured in Cameroon from scrap aluminum including car parts. • Twenty-nine cookware samples were evaluated for their potential to leach lead. • Boiling extractions to simulate the effects of cooking released significant lead. • Potential lead exposures per serving are estimated as high as 260 μg. �
Increase in the amount of erythrocyte delta-aminolevulinic acid dehydratase in workers with moderate lead exposure

International Nuclear Information System (INIS)

Fujita, H.; Sano, S.

1982-01-01

The amount of ALA-D in human erythrocytes was determined directly by radioimmunoassay or calculated from the restored activity assayed in the presence of zinc and dithiothreitol, and a good correlation was observed between the RIA-based and the restored activity-based amounts. The RIA-based amount of ALA-D in the blood of 10 normal individuals (blood lead levels of 5.6 +- 2.3 μg/100 ml: mean +- SD) and 19 lead-exposed workers (blood lead levels of 41.2 +- 10.2 μg/100 ml) was 54.1 +- 11.8 μg/ml blood and 92.3 +- 20.6 μg/ml blood, respectively, indicating an apparent increase of the enzyme amount in lead-exposed workers. A significant increase in the amount of erythrocyte ALA-D calculated from the restored activity in lead-exposed workers was observed even in the low blood lead level of 10-20 μg/100 ml, resulting in the range of blood lead level 20-40 μg/100 ml. No significant difference was observed in hematocrit and hemoglobin content between lead-exposed and non-exposed groups. These observations suggested that the increase of erythrocyte ALA-D in lead exposure was not due to anemia, which might result in the increase of young erythrocytes in peripheral blood. This increase in the amount of ALA-D in human erythrocytes might be a result of the function to overcome the inhibition of the enzyme in bone marrow cells during lead exposure, and these findings may throw light on the danger to human health of low-level lead toxicity. (orig.)
Lead poisoning in whooper and tundra swans.

Science.gov (United States)

Nakade, Tetsuya; Tomura, Yoshihiro; Jin, Kazuo; Taniyama, Hiroyuki; Yamamoto, Mutsuki; Kikkawa, Aya; Miyagi, Kunitaro; Uchida, Eiji; Asakawa, Mitsuhiko; Mukai, Takeshi; Shirasawa, Masahiko; Yamaguchi, Mamoru

2005-01-01

Six weak whooper swans (Cygnus cygnus) and two weak tundra swans (Cygnus columbianus) were found at Swamp Miyajima (Hokkaido, Japan) in May 1998. Anorexia, depression, green watery feces, pale conjunctiva, and anemia were observed. Radiographs showed from six to 38 suspected lead pellets in the gizzard. Blood lead concentrations were 2.5-6.7 microg/g (mean+/-SD=4.6+/-1.14 microg/g) on day 1. After blood collection, the birds were treated with calcium disodium ethylenediaminetetraacetate (CaEDTA) given intravenously and force fed. Despite treatment, seven birds died the next day. Green, bile-stained livers and pale or green kidneys were observed on necropsy. Microscopically, bile pigment was widespread in the liver and acid-fast intranuclear inclusion bodies were observed in renal tubular epithelium. Lead concentrations in livers and kidneys were 14.0-30.4 microg/g and 30.2-122 microg/g wet weight, respectively. Only one bird survived and this whooper swan continued to be treated with CaEDTA and activated charcoal. No lead shot was observed in the proventriculus and gizzard by radiography on day 64 and the blood lead concentration decreased from 2.9 microg/g to 0.09 microg/g during that same period. After 4 mo of rehabilitation, the whooper swan was returned to the wild. Lead intoxication continues to be a problem at Swamp Miyajima.
Soft Chemistry Preparation of lead Iron Vanadate

International Nuclear Information System (INIS)

Melghit, Khaled

2011-01-01

In order to prepare the new monoclinic Pb 2 FeV 3 O 11 at low temperature; an acidic solution of vanadium oxide, pH 2, was mixed with a corresponding amount of both lead and iron nitrate at boiling temperature. The yellow precipitate obtained is a mixture of lead pyrovanadate Pb 2 V 2 O 7 and an amorphous phase. At 500deg. C, the new monoclinic Pb 2 FeV 3 O 11 phase appears but mixed with Pb 2 V 2 O 7 . At higher temperature, 570deg. C, the monoclinic phase disappears and a new phase appears. This phase is similar to triclinic Pb 2 Fe 2 V 4 O 15 , recently reported, although the EDAX analysis shows the as-prepared sample with higher amount of vanadium and iron. To understand the mechanism involved, lead and iron nitrate solution were reacted separately with vanadium oxide solution. The phases formed were found to be sensitive to initial concentration and to stirring time
Lead-isotope inhomogeneity in Precambrian igneous K-feldspars

International Nuclear Information System (INIS)

Ludwig, K.R.; Silver, L.T.

1977-01-01

Stepwise PB-removal experiments, using both vacuum volatilization and HF-leaching techniques, on acid-washed K-feldspar concentrates from Precambrian igneous rocks show that all contain some unsupported radiogenic Pb. Two types of radiogenic Pb were recognised. One has a 'normal' isotopic composition, with relative abundances of 206 Pb, 207 Pb and 208 Pb consistent with the age and U-Th contents of the rocks. The other type of unsupported radiogenic lead in the feldspars is apparently pure 206 Pb, derived from long-term migration and accumulation of radioactive daughter(s) of 238 U. This 'pure' 206 Pb lead occupies different sites from the 'normal' radiogenic lead, and tends to show a release maximum during vacuum volatilization at about 1150 0 C. The usefulness of stepwise vacuum volatilization may be limited by the tendency of a small amount of radiogenic lead to concentrate in the least volatile fraction. Stepwise partial HF attacks appear to give at least as good separation of radiogenic from original feldspar lead, and are recommended as a routine procedure for isotopic analyses of Precambrian feldspars. The fact that most of the five K-feldspars examined contained unsupported radiogenic lead implies that caution must be used in applying total-sample lead analyses of Precambrian feldspars to problems of lead-isotope evolution in crustal rocks. (author)
Investigating on the fermentation behavior of six lactic acid bacteria strains in barley malt wort reveals limitation in key amino acids and buffer capacity.

Science.gov (United States)

Nsogning, Sorelle Dongmo; Fischer, Susann; Becker, Thomas

2018-08-01

Understanding lactic acid bacteria (LAB) fermentation behavior in malt wort is a milestone towards flavor improvement of lactic acid fermented malt beverages. Therefore, this study aims to outline deficiencies that may exist in malt wort fermentation. First, based on six LAB strains, cell viability and vitality were evaluated. Second, sugars, organic acids, amino acids, pH value and buffering capacity (BC) were monitored. Finally, the implication of key amino acids, fructose and wort BC on LAB growth was determined. Short growth phase coupled with prompt cell death and a decrease in metabolic activity was observed. Low wort BC caused rapid pH drop with lactic acid accumulation, which conversely increased the BC leading to less pH change at late-stage fermentation. Lactic acid content (≤3.9 g/L) was higher than the reported inhibitory concentration (1.8 g/L). Furthermore, sugars were still available but fructose and key amino acids lysine, arginine and glutamic acid were considerably exhausted (≤98%). Wort supplementations improved cell growth and viability leading to conclude that key amino acid depletion coupled with low BC limits LAB growth in malt wort. Then, a further increase in organic acid reduces LAB viability. This knowledge opens doors for LAB fermentation process optimization in malt wort. Copyright © 2018 Elsevier Ltd. All rights reserved.
Lead contamination of environment in Meza Valley, Yugoslavia: some considerations on lead content in soil and plants

Energy Technology Data Exchange (ETDEWEB)

Djuric, D; Kerin, Z

1970-01-01

As part of a broad ecological study of lead contamination, soil samples and underground parts of some vegetables were analyzed for lead by the dithizone method. Vegetables fell into three groups: those with a relatively high Pb content (over 30 mg/kg); those with a medium Pb content (over 10 mg/kg); and those with a low Pb content (under 5 mg/kg). Variations in Pb content in the same kind of vegetables represented variations in soil Pb content and absorption. Variations between different kinds of vegetables were due to differences in plant physiology and capacity of absorption, shape and size of root, and depth of root in soil. Lead content was higher in vegetables grown in summer and fall than for the same vegetables grown in spring. Lead absorption coefficients were calculated for underground parts of vegetables according to the relation between the Pb content of the plant and total Pb content of soil and according to the relation between the Pb content of the plant and the AL-soluble Pb in soil (AL is the ammonium lactate acetic acid mixture). The latter method gave much less dispersed coefficients, indicating that AL-soluble Pb represents much more authoritative data for determining absorption coefficients than total soil Pb.
Micro-hybrid electric vehicle application of valve-regulated lead-acid batteries in absorbent glass mat technology: Testing a partial-state-of-charge operation strategy

Energy Technology Data Exchange (ETDEWEB)

Schaeck, S.; Stoermer, A.O.; Hockgeiger, E. [BMW Group, Powertrain Development, Energy Storage, Hufelandstrasse 4, 80788 Muenchen (Germany)

2009-05-01

The BMW Group has launched two micro-hybrid functions in high volume models in order to contribute to reduction of fuel consumption in modern passenger cars. Both the brake energy regeneration (BER) and the auto-start-stop function (ASSF) are based on the conventional 14 V vehicle electrical system and current series components with only little modifications. An intelligent control algorithm of the alternator enables recuperative charging in braking and coasting phases, known as BER. By switching off the internal combustion engine at a vehicle standstill the idling fuel consumption is effectively reduced by ASSF. By reason of economy and package a lead-acid battery is used as electrochemical energy storage device. The BMW Group assembles valve-regulated lead-acid (VRLA) batteries in absorbent glass mat (AGM) technology in the micro-hybrid electrical power system since special challenges arise for the batteries. By field data analysis a lower average state-of-charge (SOC) due to partial state-of-charge (PSOC) operation and a higher cycling rate due to BER and ASSF are confirmed in this article. Similar to a design of experiment (DOE) like method we present a long-term lab investigation. Two types of 90 Ah VRLA AGM batteries are operated with a test bench profile that simulates the micro-hybrid vehicle electrical system under varying conditions. The main attention of this lab testing is focused on capacity loss and charge acceptance over cycle life. These effects are put into context with periodically refresh charging the batteries in order to prevent accelerated battery aging due to hard sulfation. We demonstrate the positive effect of refresh chargings concerning preservation of battery charge acceptance. Furthermore, we observe moderate capacity loss over 90 full cycles both at 25 C and at 3 C battery temperature. (author)
Micro-hybrid electric vehicle application of valve-regulated lead-acid batteries in absorbent glass mat technology: Testing a partial-state-of-charge operation strategy

Science.gov (United States)

Schaeck, S.; Stoermer, A. O.; Hockgeiger, E.

The BMW Group has launched two micro-hybrid functions in high volume models in order to contribute to reduction of fuel consumption in modern passenger cars. Both the brake energy regeneration (BER) and the auto-start-stop function (ASSF) are based on the conventional 14 V vehicle electrical system and current series components with only little modifications. An intelligent control algorithm of the alternator enables recuperative charging in braking and coasting phases, known as BER. By switching off the internal combustion engine at a vehicle standstill the idling fuel consumption is effectively reduced by ASSF. By reason of economy and package a lead-acid battery is used as electrochemical energy storage device. The BMW Group assembles valve-regulated lead-acid (VRLA) batteries in absorbent glass mat (AGM) technology in the micro-hybrid electrical power system since special challenges arise for the batteries. By field data analysis a lower average state-of-charge (SOC) due to partial state-of-charge (PSOC) operation and a higher cycling rate due to BER and ASSF are confirmed in this article. Similar to a design of experiment (DOE) like method we present a long-term lab investigation. Two types of 90 Ah VRLA AGM batteries are operated with a test bench profile that simulates the micro-hybrid vehicle electrical system under varying conditions. The main attention of this lab testing is focused on capacity loss and charge acceptance over cycle life. These effects are put into context with periodically refresh charging the batteries in order to prevent accelerated battery aging due to hard sulfation. We demonstrate the positive effect of refresh chargings concerning preservation of battery charge acceptance. Furthermore, we observe moderate capacity loss over 90 full cycles both at 25 °C and at 3 °C battery temperature.
Thermal and Hydrolytic Stability of Dithiophophoric Acids Stabilité thermique et hydrolytique des acides dithiophosphoriques

Directory of Open Access Journals (Sweden)

Ivanov S. K.

2006-11-01

Full Text Available The thermal and hydrolytic stability of dibutyl-, diisobutyl- and diisooctyldithiophosphoric acids have been studied in the range of 40-80°C. The reaction progress was followed by the H2S evolution kinetics in volumetric equipment at constant pressure, equal to the barometric one. The kinetic parameters of the process have been determined at various acid water ratios - maximum rates of gas evolution, activation energy and the kinetic order. It has been shown that the hydrolysis proceeds mainly along the sulph-hydrate group of the acid (up to temperatures of 60°C, while at higher temperatures the ester groups and the thion sulphur are attacked too. The thermal stability of dithiophosphoric acids has been studied in the presence of stainless steel, lead and copper plates. It has been shown that stainless steel doesn't affect the process rate, while copper and especially lead increase the gas evolution and decrease the activation energy. A model describing the reaction progress at the interfacial surfaces - organic phase, water and metal surface - has been developed. Based on these data a conclusion is advanced, related to the manifacture technology of antioxidant, anticorrosion and antiwear additives of the zinc dialkyldithiophosphate type. It is pointed out that the neutralization process of dithiophosphoric acids should be carried out in a stainless steel reactor at tempeatures below 70°C. Le présent article s'efforce d'élucider l'influence de l'eau, de la température et des surfaces métalliques sur la stabilité thermique et hydrolytique des acides dibutyl-, diisobutyl- et diisooctyldithiophosphoriques, à la lumière du concept d'interaction.

Acid drainage at the inactive Santa Lucia mine, western Cuba: Natural attenuation of arsenic, barium and lead, and geochemical behavior of rare earth elements

Energy Technology Data Exchange (ETDEWEB)

Romero, Francisco Martin, E-mail: fmrch@geologia.unam.mx [Instituto de Geologia, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, Delegacion Coyoacan, 04510 Mexico D.F. (Mexico); Prol-Ledesma, Rosa Maria; Canet, Carles [Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, Delegacion Coyoacan, 04510 Mexico D.F. (Mexico); Alvares, Laura Nunez; Perez-Vazquez, Ramon [Facultad de Geologia y Mecanica, Universidad de Pinar del Rio (Cuba)

2010-05-15

A detailed geochemical study was conducted at the inactive Zn-Pb mine of Santa Lucia, in western Cuba. The studied mine-wastes are characterized by high total concentrations of potentially toxic elements (PTE), with average values of 17.4% Fe, 5.47% Ba, 2.27% Pb, 0.83% Zn, 1724 mg/kg As and 811 mg/kg Cu. Oxidation of sulfide minerals in mine-waste dumps and in the open pit produces acid mine effluents (pH = 2.5-2.6) enriched in dissolved SO{sub 4}{sup 2-} (up to 6754 mg/L), Fe (up to 4620 mg/L) and Zn (up to 2090 mg/L). Low pH values (2.5-2.8) and high dissolved concentrations of the same PTE were found in surface waters, up to 1500 m downstream from the mine. Nevertheless, concentrations of As, Ba and Pb in acid mine effluents and impacted surface waters are relatively low: 0.01-0.3 mg/L As, 0.002-0.03 mg/L Ba and 0.3-4.3 mg/L Pb. Analysis by X-ray diffraction and electron microscopy revealed the occurrence of lead-bearing barite and beudantite and the more common solid phases, reported elsewhere in similar environments including Fe-oxyhydroxides, jarosite, anglesite and plumbojarosite. Because the reported solubilities for barite and beudantite are very low under acidic conditions, these minerals may serve as the most important control in the mobility of As, Ba and Pb. In contrast, Fe-oxyhydroxides are relatively soluble under acidic conditions and, therefore, they may have a less significant role in PTE on-site immobilization. Mine-wastes and stream sediments show a light REE (LREE) and middle REE (MREE) enrichment relative to heavy REE (HREE). In contrast, acid mine effluents and surface waters are enriched in HREE relative to LREE. These results suggest that the LREE released during the oxidation of sulfides are captured by secondary (weathering) minerals, while the MREE are removed from the altered rocks. The low concentrations of LREE in acid stream water suggest that these elements can be retained in the sediments more strongly than HREE and MREE. One
FATTY ACID ETHYL ESTERS FROM MICROALGAE OF Scenedesmus ecornis BY ENZYMATIC AND ACID CATALYSIS

Directory of Open Access Journals (Sweden)

Gabryelle F. de Almeida

Full Text Available Microalgae are an indispensable food source for the various growth stages of mollusks, crustaceans, and several fish species. Using a microalgae biomass present in the Amazonian ecosystem (Macapá-AP, we study extraction methods for fatty acid such as solvent extraction (magnetic stirring and/or Soxhlet and/or hydrolysis (acid and/or enzymatic catalysis followed by esterification and/or direct transesterification. Extraction of crude triacylglycerides by mechanical stirring at room temperature was more efficient than continuous reflux (Soxhlet. Subsequently, the lipid extract was subject to transesterification with ethanol and CAL-B as a biocatalyst, leading to production of fatty acid ethyl esters (FAEE. Additionally, FAEEs were prepared by hydrolysis of crude triacylglycerides followed by acid-mediated esterification or enzymatic catalysis (lipase. In this case, the type of catalyst did not significantly influence FAEE yields. In the lipid extract, we identified palmitic, linoleic, oleic, and stearic acids with palmitic acid being the most abundant. Our results suggest that enzymatic catalysis is a viable method for the extraction of lipids in the microalga, Scenedesmus ecornis.
Portable nucleic acid thermocyclers.

Science.gov (United States)

Almassian, David R; Cockrell, Lisa M; Nelson, William M

2013-11-21

A nucleic acid thermal cycler is considered to be portable if it is under ten pounds, easily carried by one individual, and battery powered. Nucleic acid amplification includes both polymerase chain reaction (e.g. PCR, RT-PCR) and isothermal amplification (e.g. RPA, HDA, LAMP, NASBA, RCA, ICAN, SMART, SDA). There are valuable applications for portable nucleic acid thermocyclers in fields that include clinical diagnostics, biothreat detection, and veterinary testing. A system that is portable allows for the distributed detection of targets at the point of care and a reduction of the time from sample to answer. The designer of a portable nucleic acid thermocycler must carefully consider both thermal control and the detection of amplification. In addition to thermal control and detection, the designer may consider the integration of a sample preparation subsystem with the nucleic acid thermocycler. There are a variety of technologies that can achieve accurate thermal control and the detection of nucleic acid amplification. Important evaluation criteria for each technology include maturity, power requirements, cost, sensitivity, speed, and manufacturability. Ultimately the needs of a particular market will lead to user requirements that drive the decision between available technologies.
Uranium extraction from phosphoric acid

International Nuclear Information System (INIS)

Lounis, A.

1983-05-01

A study has been carried out for the extraction of uranium from phosphoric acid produced in Algeria. First of all, the Algerian phosphoric acid produced in Algeria by SONATRACH has been characterised. This study helped us to synthesize a phosphoric acid that enabled us to pass from laboratory tests to pilot scale tests. We have then examined extraction and stripping parameters: diluent, DZEPHA/TOPO ratio and oxidising agent. The laboratory experiments enabled us to set the optimum condition for the choice of diluent, extractant concentration, ratio of the synergic mixture, oxidant concentration, redox potential. The equilibrium isotherms lead to the determination of the number of theoretical stages for the uranium extraction and stripping of uranium, then the extraction from phosphoric acid has been verified on a pilot scale (using a mixer-settler)
Vanadocene reactions with hydroxy acids

International Nuclear Information System (INIS)

Latyaeva, V.N.; Lineva, A.N.; Zimina, S.V.; Ehllert, O.G.; Arsen'eva, T.I.

1984-01-01

To prepare a series of vanadium cyclopentadienylcarboxylates soluble in water, the vanadocene reactions with lactic, γ-oxybutyric-, salicylic,- gallic-, orotic-, and acetylsalicylic acids have been studied. To determine the influence of cyclopentadienyl groups, bound with a vanadium atom, on the physiological activity of the complexes formed, vanadium halides are made to react with lactic acid. Only the vanadocene reaction with orotic acid was conducted in an aqueous medium, other interactions were realized in the diethyl ether, toluene, T, H, P medium. The interaction of vanadocene and vanadium halides with lactic-, salicylic-, acetylsalicylic- and gallic acids was found to lead to the formation of water-soluble vanadium complexes of Cp 2 , VOCOR or CpV (OCOR) 2 type. The data on the produced compounds yield, their IR spectra, decomposition temperatures, solubility, effective magnetic moments are presented
Effects of decreasing acid deposition and climate change on acid extremes in an upland stream

Directory of Open Access Journals (Sweden)

C. D. Evans

2008-03-01

Full Text Available This study assesses the major chemical processes leading to acid extremes in a small, moorland stream in mid-Wales, UK, which has been monitored since 1979. Results suggest that base cation (mainly calcium dilution, the "sea-salt effect", and elevated nitrate pulses, are the major causes of seasonal/episodic minima in acid neutralising capacity (ANC, and that the relative importance of these drivers has remained approximately constant during 25 years of decreasing acid deposition and associated long-term chemical recovery. Many of the chemical variations causing short-term reductions in stream acidity, particularly base cation dilution and organic acid increases, are closely related to changes in water-flowpath and therefore to stream discharge. Changes in the observed pH-discharge relationship over time indicate that high-flow pH has increased more rapidly than mean-flow pH, and therefore that episodes have decreased in magnitude since 1980. However a two-box application of the dynamic model MAGIC, whilst reproducing this trend, suggests that it will not persist in the long term, with mean ANC continuing to increase until 2100, but the ANC of the upper soil (the source of relatively acid water during high-flow episodes stabilising close to zero beyond 2030. With climate change predicted to lead to an increase in maximum flows in the latter half of the century, high-flow related acid episodes may actually become more rather than less severe in the long term, although the model suggests that this effect may be small. Two other predicted climatic changes could also detrimentally impact on acid episodes: increased severity of winter "sea-salt" episodes due to higher wind speeds during winter storms; and larger sulphate pulses due to oxidation of reduced sulphur held in organic soils, during more extreme summer droughts. At the Gwy, the near-coastal location and relatively small extent of peat soils suggest that sea-salt episodes may have the
Effects of Docosahexaenoic Acid on Neurotransmission

OpenAIRE

Tanaka, Kazuhiro; Farooqui, Akhlaq A.; Siddiqi, Nikhat J.; Alhomida, Abdullah S.; Ong, Wei-Yi

2012-01-01

Docosahexaenoic acid (DHA) is the major polyunsaturated fatty acid (PUFA) in the brain and a structural component of neuronal membranes. Changes in DHA content of neuronal membranes lead to functional changes in the activity of receptors and other proteins which might be associated with synaptic function. Accumulating evidence suggests the beneficial effects of dietary DHA supplementation on neurotransmission. This article reviews the beneficial effects of DHA on the brain; uptake, incorporat...
Lead isotope ratios in Japanese galena ores and archaeological objects

International Nuclear Information System (INIS)

Yamasaki, Kazuo; Murozumi, Masayo; Nakamura, Seiji; Hinata, Makoto; Yuasa, Mitsuaki.

1978-01-01

Lead isotope ratios 206 Pb/ 204 Pb, 207 Pb/ 204 Pb, 208 Pb/ 204 Pb, 207 Pb/ 206 Pb and 208 Pb/ 206 Pb in Japanese galena ores and archaeological bronze objects were determined by a Hitachi RMU-6 mass spectrometer using a rhenium single filament as a surface ionization device. Basic experimental conditions including detection limit, fractionation effect, memory effect, etc. were examined, and the accuracy of determination was checked using the CIT shelf standard No. 1. Archaeological bronze objects were dissolved in nitric acid and lead was extracted by the dithizone method using specially purified reagents in a so-called clean laboratory. When 0.5 μg lead was loaded on the rhenium filament with phosphoric acid and silica gel as stabilizers, an ion current of 10 -13 -- 10 -15 A due to Pb + was obtained and maintained stable for several hours. Coefficients of variation found for the isotope ratios 207 Pb/ 206 Pb and 208 Pb/ 206 Pb were 0.1 -- 0.5%. Lead isotope ratios are given for 17 Japanese galena ores and for archaeological bronze objects such as bronze bells, halberds (Yayoi period), Horyuji pagoda spire (7th century), and Northern Sung coins (11th century). A close resemblance of the isotope ratios was found between Japanese galena ores and some Japanese bronze objects of the 7th century, suggesting the use of the former as raw materials of the latter. (auth.)
Ionotropic excitatory amino acid receptor ligands. Synthesis and pharmacology of a new amino acid AMPA antagonist

DEFF Research Database (Denmark)

Madsen, U; Sløk, F A; Stensbøl, T B

2000-01-01

We have previously described the potent and selective (RS)-2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid (AMPA) receptor agonist, (RS)-2-amino-3-(3-carboxy-5-methyl-4-isoxazolyl)propionic acid (ACPA), and the AMPA receptor antagonist (RS)-2-amino-3-[3-(carboxymethoxy)-5-methyl-4...... excitatory amino acid (EAA) receptors using receptor binding and electrophysiological techniques, and for activity at metabotropic EAA receptors using second messenger assays. Compounds 1 and 4 were essentially inactive. (RS)-2-Amino-3-[3-(2-carboxyethyl)-5-methyl-4-isoxazolyl]propionic acid (ACMP, 2......-isoxazolyl]propionic acid (AMOA). Using these AMPA receptor ligands as leads, a series of compounds have been developed as tools for further elucidation of the structural requirements for activation and blockade of AMPA receptors. The synthesized compounds have been tested for activity at ionotropic...
QUANTIFICATION OF LEAD AND CADMIUM IN POULTRY AND BIRD GAME MEAT BY SQUARE WAVE ANODIC STRIPPING VOLTAMMETRY

OpenAIRE

2011-01-01

Abstract A Square Wave Anodic Stripping Voltammetric method for the analysis of lead and cadmium in chicken muscle and liver was developed and validated, and the results of a monitoring study relative to chicken and pigeon meat are reported. The voltammetric method allows the analysis of lead and cadmium at the same time in samples after acid digestion. The use of perchloric acid for digestion and of acetate buffer in the supporting electrolyte have been found suitable to reduce ma...
Random amino acid mutations and protein misfolding lead to Shannon limit in sequence-structure communication.

Directory of Open Access Journals (Sweden)

Andreas Martin Lisewski

2008-09-01

Full Text Available The transmission of genomic information from coding sequence to protein structure during protein synthesis is subject to stochastic errors. To analyze transmission limits in the presence of spurious errors, Shannon's noisy channel theorem is applied to a communication channel between amino acid sequences and their structures established from a large-scale statistical analysis of protein atomic coordinates. While Shannon's theorem confirms that in close to native conformations information is transmitted with limited error probability, additional random errors in sequence (amino acid substitutions and in structure (structural defects trigger a decrease in communication capacity toward a Shannon limit at 0.010 bits per amino acid symbol at which communication breaks down. In several controls, simulated error rates above a critical threshold and models of unfolded structures always produce capacities below this limiting value. Thus an essential biological system can be realistically modeled as a digital communication channel that is (a sensitive to random errors and (b restricted by a Shannon error limit. This forms a novel basis for predictions consistent with observed rates of defective ribosomal products during protein synthesis, and with the estimated excess of mutual information in protein contact potentials.
Folic acid fortification and public health: report on threshold doses above which unmetabolised folic acid appear in serum.

LENUS (Irish Health Repository)

Sweeney, Mary Rose

2007-01-01

BACKGROUND: All flour in the USA is fortified with folic acid at a level of 140 microg\\/100 g which is estimated to supply an extra 100 microg daily to the average diet. Some researchers have advocated that this be increased to double and even four times this amount. Based on previous research these higher levels are likely to lead to the appearance of unmetabolised vitamin in the circulation, which may have safety implications for sub-groups of the population. The UK and the Republic of Ireland will likely introduce mandatory fortification also in the next year or so. The aim of this study was to capture the short-term effect of folic acid fortification on unmetabolised folic acid in serum after chronic consumption of folic acid. METHODS: After pre-saturation with 400 microg folic acid supplements daily for 14-weeks, healthy folate replete adults (n = 20) consumed folic acid fortified bread, at three different levels (400 microg, 200 microg, 100 microg) over a period of one week each. The dose was administered in two-equal sized slices consumed at 09.00 hrs and 13.00 hrs. Serum samples for total folate and folic acid were collected at baseline, after 14-weeks of supplementation, and pre and post (at 1, 2, 3 and 4 hours) each dose tested. RESULTS: Unmetabolised folic acid was detected after the 14-week supplementation period. Folic acid was not detected in either the 200 microg or 100 microg (current US regime) doses tested but was present at the highest level (400 microg) tested. CONCLUSION: Our findings suggest that persons exposed to the current US fortification programme supplying an average of 100 microg per day or less are unlikely to have unmetabolised folic acid in serum. It also seems that daily consumption of the higher level of 200 microg or less is unlikely to be problematic. Increasing the level however to 400 microg on the other hand is likely to lead to unmetabolised folic acid appearance.
Reactions of acetylenes with hypophosphorous and phosphonous acids

International Nuclear Information System (INIS)

Nifant'ev, E.E.; Solovetskaya, L.A.; Maslennikova, V.I.; Magdeeva, R.K.; Sergeev, N.M.

1986-01-01

Alkenylphosphonous, alkenylphosphinic, and alkylenebisphosphinic acids were prepared for the first time. The course of the hydrophosphorylation of 1-alkynes depends on the form of the reagent used. The homolytic hydrophosphorylation of acetylenes with hypophosphorous acid proceeds mainly with the participation of one molecule of the acid. The addition of phosphonous acids to acetylenic hydrocarbons leads to both mono- and di-phosphorylated adducts. The nature of the phosphonous acid taken has a substantial influence on the readiness with which the alkylenebisphosphinic acids are formed. Study of the stereoselectivity of the reactions showed that in the case of the monoaddition of hypophosphorous and phosphonous acids to acetylenes mixtures of cis and trans isomeric products are always formed. Phosphorous 31 and carbon 13 NMR spectra are analyzed
Sleep disorders and the prevalence of asymptomatic nocturnal acid and non-acid reflux.

Science.gov (United States)

Herdman, Christine; Marzio, Dina Halegoua-De; Shah, Paurush; Denuna-Rivera, Susie; Doghramji, Karl; Cohen, Sidney; Dimarino, Anthony J

2013-01-01

Nocturnal acid reflux is associated with symptomatic and asymptomatic sleep arousals, leading to fragmented sleep. The frequency and influence of acid reflux in patients with various forms of insomnia has not been reported. The aim of this study was to quantify nocturnal acid and nonacid reflux in patients with primary sleep disorders as previously diagnosed by polysomnography. THIRTY ONE SUBJECTS WERE STUDIED: (A) 9 subjects with a polysomnographically diagnosed sleep disorder (1 with restless legs syndrome, 4 with narcolepsy, 4 with periodic limb movement disorder); (B) 12 subjects with primary insomnia (PI) and unrevealing polysomnography; and (C) 10 controls without disturbed sleep. All subjects underwent a physical examination and 24 h transnasal pH and impedance monitoring to detect acid and non-acid reflux. The 21 subjects with fragmented sleep due to a primary sleep disorder had significantly more recumbent acid exposure (>1.2% of time) as compared with control subjects (33% versus 0%). When fragmented sleep subjects were divided into two groups, 17% of PI subjects and 55% of subjects with a diagnosed sleep disorder had significant recumbent acid exposure (P=0.009). Likewise, the median recumbent nonacid events were increased in the sleep disordered group (P=0.011). This study indicates that patients with primary sleep disorders have prominent nocturnal acid reflux without symptoms of daytime acid reflux. Acid reflux is most prominent in patients with polysomnographic findings of disturbed sleep as compared to patients with PI; while non acid reflux is increased minimally in these patients.
Development of a lead acid battery suitable for electric vehicle propulsion. Final report. [96 V, 20 kWh, 50 Wh/kg

Energy Technology Data Exchange (ETDEWEB)

Schlotter, W J

1977-08-26

This report contains two detailed designs, and the design rationale, for an improved state-of-the-art electric vehicle battery incorporating expanded metal grids. The nominal 96-volt and 20-kWh battery incorporating this improved design is expected to cost about 25% less when manufactured in a mature plant. This report also contains detailed estimates for the capital cost and operating cost of a pilot plant to produce electric vehicle battery plates incorporating expanded metal grids. It is expected that the first electric vehicle batteries incorporating expanded metal grids can be available fifteen months after approval of this program. An additional program to improve lead acid batteries for electric vehicles further is also described. The advanced batteries resulting from this program are expected to incorporate either expanded metal grids and/or composite lead/plastic grids. In addition, these batteries are expected to contain low-density active materials. It is anticipated that those additional developments will result in an advanced battery capable of delivering 45 to 50 watt-hours/kg. As a result of the design and cost study, a ''First Buy'' improved state-of-the art vehicle battery proposed is included as part of this report. Eltra proposes to manufacture and deliver the required 2500 vehicle batteries within the time limits set forth by the Electric and Hybrid Vehicle Research, Development, and Demonstration Act of 1976. 20 figures, 13 tables.
Trace analysis of lead and cadmium in seafoods by differential pulse anodic stripping voltametry

International Nuclear Information System (INIS)

Sumera, F.C.; Verceluz, F.P.; Kapauan, P.A.

1979-01-01

A method for the simultaneous determination of cadmium and lead in seafoods is described. The sample is dry ashed in a muffle furnace elevating the temperature gradually up to 500 0 C. The ashed sample is treated with concentrated nitric acid, dried on a heating plate and returned to the muffle furnace for further heating. The treated ash is then dissolved in 1 N HCL acetate buffer and citric acid are added and the pH adjusted to 3.6-4. The resulting solution is analyzed for lead and cadmium by differential pulse anodic stripping voltametry (DPASV) using a wax-impregnated graphite thin film electrode. The average recoveries of 0.4 of cadmium and lead added to 5 fish samples were 97% and 99% respectively. The standard deviations, on a homogenized shark sample for lead and cadmium analysis were 6.7 ppb and 12.3 ppb, respectively, and the relative standard deviations were 21.0% and 15.5% respectively. Studies on instrumental parameters involved in the DPASV step of analysis and methods of measuring peak current signals were also made. (author)
The fabrication and characterization of an ex situ plated lead film electrode prepared with the use of a reversibly deposited mediator metal

International Nuclear Information System (INIS)

Tyszczuk, Katarzyna

2011-01-01

Research highlights: → The lead film electrode prepared with use of the mediator metal was elaborated. → The lead-based sensors were characterized by optical and voltammetric methods. → The adsorptive system of folic acid was employed to investigate a new electrode. → The application of the mediator metal improved properties of a lead film electrode. - Abstract: In this paper an ex situ plated lead film electrode prepared with use of the mediator metal (Zn) was elaborated. The electrochemical method for lead film formation is based on a co-deposition of a metal of interest (Pb) with a reversibly deposited mediator metal (Zn) and then on an oxidation of zinc and further deposition of lead by the appropriate potential. This serves to increase the density of islands of lead atoms, promoting lead film growth. The lead-based sensors were characterized by optical method (atomic force microscopy (AFM)) and as well as cyclic, linear sweep and square wave voltammetry. The adsorptive system of folic acid was employed to investigate the electrochemical characteristics a novel type of lead film electrode. Well-formed stripping peaks and a linear dependence of the stripping current on the folic acid concentration were observed on the lead film electrode prepared with use of the mediator metal while comparative measurements attempted with the lead film electrode prepared without use of the mediator metal were unsuccessful.
Amino Acids from a Comet

Science.gov (United States)

Cook, Jamie Elisla

2009-01-01

NASA's Stardust spacecraft returned samples from comet 81P/Wild 2 to Earth in January 2006. Examinations of the organic compounds in cometary samples can reveal information about the prebiotic organic inventory present on the early Earth and within the early Solar System, which may have contributed to the origin of life. Preliminary studies of Stardust material revealed the presence of a suite of organic compounds including several amines and amino acids, but the origin of these compounds (cometary- vs. terrestrial contamination) could not be identified. We have recently measured the carbon isotopic ratios of these amino acids to determine their origin, leading to the first detection of a coetary amino acid.
Production of Odd-Carbon Dicarboxylic Acids in Escherichia coli Using an Engineered Biotin–Fatty Acid Biosynthetic Pathway

Energy Technology Data Exchange (ETDEWEB)

Haushalter, Robert W. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Physical Bioscience Division; Phelan, Ryan M. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Physical Bioscience Division; Hoh, Kristina M. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Physical Bioscience Division; Su, Cindy [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Physical Bioscience Division; Wang, George [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Physical Bioscience Division; Baidoo, Edward E. K. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Physical Bioscience Division; Keasling, Jay D. [Joint BioEnergy Inst. (JBEI), Emeryville, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Physical Bioscience Division

2017-03-14

Dicarboxylic acids are commodity chemicals used in the production of plastics, polyesters, nylons, fragrances, and medications. Bio-based routes to dicarboxylic acids are gaining attention due to environmental concerns about petroleum-based production of these compounds. Some industrial applications require dicarboxylic acids with specific carbon chain lengths, including odd-carbon species. Biosynthetic pathways involving cytochrome P450-catalyzed oxidation of fatty acids in yeast and bacteria have been reported, but these systems produce almost exclusively even-carbon species. Here in this paper we report a novel pathway to odd-carbon dicarboxylic acids directly from glucose in Escherichia coli by employing an engineered pathway combining enzymes from biotin and fatty acid synthesis. Optimization of the pathway will lead to industrial strains for the production of valuable odd-carbon diacids.
Magnetic Vinylphenyl Boronic Acid Microparticles for Surface Catalytic Performance in Esterification of Propionic Acid with Methanol

Directory of Open Access Journals (Sweden)

Ali Kara

2016-12-01

Full Text Available Magnetic vinylphenyl boronic acid microparticles, poly(ethylene glycol dimethacrylate-vinylphenyl boronic acid [m-poly(EGDMA-VPBA], produced by suspension polymerization, was found to be efficient solid acid catalyst for the esterification of methanol and propionic acid. Characterization techniques such as FT-IR, Elemental analyses, ICP-AES, ESR, SEM and N2 sorption showed that both of Fe3O4 and H2SO4 are bonded to the polymer successfully. Esterification was studied for different molar percentages of H2SO4 at temperature range of 50-70 oC. The apparent activation energy was found to be 27.7 kj.mol-1 for 10% H2SO4 doped m-poly(EGDMA-VPBA. Combining of strong acid H2SO4 with m-poly(EGDMA-VPBA, leads to materials with different functional properties. In addition, H2SO4 species could be introduced into the structure as acid centers, therefore this micro-dimensional catalyst has potential candidate for applications in the catalytic esterifications such as propionic acid with methanol.

Investigation of Released Cadmium and Lead from Different Colors of Over Glaze Designs to Food Stuff in Different Conditions

Directory of Open Access Journals (Sweden)

H. Hashemi-Moghaddam

2012-03-01

Full Text Available In this paper, leaching of lead and cadmium was investigated from porcelain over glaze designs between different colors. Also the effect of microwave heating was considered on leaching of lead and cadmium. Dishes were selected with a decor with the dominant color of gray, red, yellow, blue, and dark blue. Amounts of cadmium and lead which leached from the container by acetic acid and orange juice were measured according to the standard ASTM C738. The results showed that especially in the red and dark blue colors cadmium and lead could be released easily by either acetic acid or orange juice, and these amounts were much higher than the permissible standard amount. Also microwave heating could enhance releasing of lead and cadmium from decorated dinnerware.
Selective oxidation of glycerol to formic acid in highly concentrated aqueous solutions with molecular oxygen using V-substituted phosphomolybdic acids

KAUST Repository

Zhang, Jizhe

2014-01-01

Formic acid is an important commodity chemical as well as a promising medium for hydrogen storage and hydrogen production. In this paper, we report that formic acid can be produced through selective oxidation of glycerol, a low-cost by-product of biodiesel, by using vanadium-substituted phosphomolybdic acids as catalysts and molecular oxygen as the oxidant. Significantly, this catalytic system allows for high-concentration conversions and thus leads to exceptional efficiency. Specifically, 3.64 g of formic acid was produced from 10 g of glycerol/water (50/50 in weight) solution. © 2014 the Partner Organisations.
Potentiometric titration and equivalent weight of humic acid

Science.gov (United States)

Pommer, A.M.; Breger, I.A.

1960-01-01

The "acid nature" of humic acid has been controversial for many years. Some investigators claim that humic acid is a true weak acid, while others feel that its behaviour during potentiometric titration can be accounted for by colloidal adsorption of hydrogen ions. The acid character of humic acid has been reinvestigated using newly-derived relationships for the titration of weak acids with strong base. Re-interpreting the potentiometric titration data published by Thiele and Kettner in 1953, it was found that Merck humic acid behaves as a weak polyelectrolytic acid having an equivalent weight of 150, a pKa of 6.8 to 7.0, and a titration exponent of about 4.8. Interdretation of similar data pertaining to the titration of phenol-formaldehyde and pyrogallol-formaldehyde resins, considered to be analogs for humic acid by Thiele and Kettner, leads to the conclusion that it is not possible to differentiate between adsorption and acid-base reaction for these substances. ?? 1960.
Kinetics and mechanism of the oxidation of formic and oxalic acids ...

Indian Academy of Sciences (India)

The oxidation of formic and oxalic acids by benzyltrimethylammonium dichloroiodate (BTMACI), in the presence of zinc chloride, leads to the formation of carbon dioxide. The reaction is first order with respect to BTMACI, zinc chloride and organic acid. Oxidation of deuteriated formic acid indicates the presence of a kinetic ...
Pharmacological evaluation of novel dimers of an arylpropionic acid ...

African Journals Online (AJOL)

Purpose: To explore and identify cyclooxygenase (COX) inhibitors with optimal potency and efficacy using an arylpropionic acid class of drugs as lead molecules. Methods: The selected lead molecules were dimerised through chemical processes (reflux condensation) and characterised in terms of structural properties ...
Recovery of Tin and Nitric Acid from Spent Solder Stripping Solutions

International Nuclear Information System (INIS)

Ahn, Jae-Woo; Ryu, Seong-Hyung; Kim, Tae-young

2015-01-01

Spent solder-stripping solutions containing tin, copper, iron, and lead in nitric acid solution, are by-products of the manufacture of printed-circuit boards. The recovery of these metals and the nitric acid, for re-use has economic and environmental benefits. In the spent solder-stripping solution, a systematic method to determine a suitable process for recovery of valuable metals and nitric acid was developed. Initially, more than 90% of the tin was successfully recovered as high-purity SnO 2 by thermal precipitation at 80 ℃ for 3 hours. About 94% of the nitric acid was regenerated effectively from the spent solutions by diffusion dialysis, after which there remained copper, iron, and lead in solution. Leakage of tin through the anion-exchange membrane was the lowest (0.026%), whereas Pb-leakage was highest (4.26%). The concentration of the regenerated nitric acid was about 5.1 N.
Influence of expander components on the processes at the negative plates of lead-acid cells on high-rate partial-state-of-charge cycling. Part I: Effect of lignosulfonates and BaSO{sub 4} on the processes of charge and discharge of negative plates

Energy Technology Data Exchange (ETDEWEB)

Pavlov, D.; Nikolov, P.; Rogachev, T. [Institute of Electrochemistry and Energy Systems, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Street, bl. 10, Sofia 1113 (Bulgaria)

2010-07-15

This study investigates the influence of the organic expander component (Vanisperse A) and of BaSO{sub 4} on the performance of negative lead-acid battery plates on high-rate partial-state-of-charge (HRPSoC) cycling. Batteries operating in the HRPSoC mode should be classified as a separate type of lead-acid batteries. Hence, the additives to the negative plates should differ from the conventional expander composition. It has been established that lignosulfonates are adsorbed onto the lead surface and thus impede the charge processes, which results in impaired reversibility of the charge-discharge processes and hence shorter cycle life on HRPSoC operation, limited by sulfation of the negative plates. BaSO{sub 4} exerts the opposite effect: it improves the reversibility of the processes in the HRPSoC mode and hence prolongs the cycle life of the cells. The most pronounced effect of BaSO{sub 4} has been registered when it is added in concentration of 1.0 wt.% versus the leady oxide (LO) used for paste preparation. It has also been established that BaSO{sub 4} lowers the overpotential of PbSO{sub 4} nucleation. The results of the present investigation indicate that BaSO{sub 4} affects also the crystallization process of Pb during cell charging. Thus, BaSO{sub 4} eventually improves the performance characteristics of lead-acid cells on HRPSoC cycling. (author)
Uric Acid, Hyperuricemia and Vascular Diseases

Science.gov (United States)

Jin, Ming; Yang, Fan; Yang, Irene; Yin, Ying; Luo, Jin Jun; Wang, Hong; Yang, Xiao-Feng

2011-01-01

Uric acid is the product of purine metabolism. It is known that hyperuricemia, defined as high levels of blood uric acid, is the major etiological factor of gout. A number of epidemiological reports have increasingly linked hyperuricemia with cardiovascular and neurological diseases. Studies highlighting the pathogenic mechanisms of uric acid point to an inflammatory response as the primary mechanism for inducing gout and possibly contributing to uric acid's vascular effects. Monosodium urate (MSU) crystals induce an inflammatory reaction, which are recognized by Toll-like receptors (TLRs). These TLRs then activate NALP3 inflammasome. MSU also triggers neutrophil activation and further produces immune mediators, which lead to a proinflammatory response. In addition, soluble uric acid can also mediate the generation of free radicals and function as a pro-oxidant. This review summarizes the epidemiological studies of hyperuricemia and cardiovascular disease, takes a brief look at hyperuricemia and its role in neurological diseases, and highlights the studies of the advanced pathological mechanisms of uric acid and inflammation. PMID:22201767
Source and impact of lead contamination on {delta}-aminolevulinic acid dehydratase activity in several marine bivalve species along the Gulf of Cadiz

Energy Technology Data Exchange (ETDEWEB)

Company, R.; Serafim, A.; Lopes, B.; Cravo, A. [CIMA, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Kalman, J.; Riba, I.; DelValls, T.A. [Catedra UNESCO/UNITWIN/WiCop, Department of Physical-Chemistry, Faculty Marine and Environmental Sciences, University of Cadiz, 11510 Puerto Real, Cadiz (Spain); Blasco, J. [Instituto Ciencias Marinas Andalucia (CSIC), Campus Rio San Pedro, 11510 Puerto Real, Cadiz (Spain); Delgado, J. [Department of Geology, University of Huelva, Avda Fuerzas Armadas s/n, 21071 Huelva (Spain); Sarmiento, A.M. [Catedra UNESCO/UNITWIN/WiCop, Department of Physical-Chemistry, Faculty Marine and Environmental Sciences, University of Cadiz, 11510 Puerto Real, Cadiz (Spain); Department of Geology, University of Huelva, Avda Fuerzas Armadas s/n, 21071 Huelva (Spain); Nieto, J.M. [Department of Geology, University of Huelva, Avda Fuerzas Armadas s/n, 21071 Huelva (Spain); Shepherd, T.J.; Nowell, G. [Department of Earth Sciences, University of Durham, Science Laboratories, Durham DH1 3LE (United Kingdom); Bebianno, M.J., E-mail: mbebian@ualg.pt [CIMA, University of Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

2011-01-17

Coastal areas and estuaries are particularly sensitive to metal contamination from anthropogenic sources and in the last few decades the study of space-time distribution and variation of metals has been extensively researched. The Gulf of Cadiz is no exception, with several rivers draining one of the largest concentrations of sulphide deposits in the world, the Iberian Pyrite Belt (IPB). Of these rivers, the Guadiana, one of the most important in the Iberian Peninsula, together with smaller rivers like the Tinto and Odiel, delivers a very high metal load to the adjacent coastal areas. The purpose of this work was to study the source and impact of lead (Pb) drained from historical or active mining areas in the IPB on the activity of a Pb inhibited enzyme ({delta}-aminolevulinic acid dehydratase, ALAD) in several bivalve species along the Gulf of Cadiz. Seven marine species (Chamelea gallina, Mactra corallina, Donax trunculus, Cerastoderma edule, Mytilus galloprovincialis, Scrobicularia plana and Crassostrea angulata) were collected at 12 sites from Mazagon, near the mouth of the rivers Tinto and Odiel (Spain), to Cacela Velha (Ria Formosa lagoon system, Portugal). Lead concentrations, ALAD activity and lead isotope ratios ({sup 206}Pb/{sup 204}Pb, {sup 207}Pb/{sup 204}Pb and {sup 208}Pb/{sup 204}Pb) were determined in the whole soft tissues. The highest Pb concentrations were determined in S. plana (3.50 {+-} 1.09 {mu}g g{sup -1} Pb d.w.) and D. trunculus (1.95 {+-} 0.10 {mu}g g{sup -1} Pb d.w.), while M. galloprovincialis and C. angulata showed the lowest Pb levels (<0.38 {mu}g g{sup -1} Pb d.w.). In general, ALAD activity is negatively correlated with total Pb concentration. However this relationship is species dependent (e.g. linear for C. gallina ALAD = -0.36[Pb] + 0.79; r = 0.837; or exponential for M. galloprovincialis ALAD = 2.48e{sup -8.3[Pb]}; r = 0.911). This indicates that ALAD activity has considerable potential as a biomarker of Pb and moreover, in
Source and impact of lead contamination on δ-aminolevulinic acid dehydratase activity in several marine bivalve species along the Gulf of Cadiz

International Nuclear Information System (INIS)

Company, R.; Serafim, A.; Lopes, B.; Cravo, A.; Kalman, J.; Riba, I.; DelValls, T.A.; Blasco, J.; Delgado, J.; Sarmiento, A.M.; Nieto, J.M.; Shepherd, T.J.; Nowell, G.; Bebianno, M.J.

2011-01-01

Coastal areas and estuaries are particularly sensitive to metal contamination from anthropogenic sources and in the last few decades the study of space-time distribution and variation of metals has been extensively researched. The Gulf of Cadiz is no exception, with several rivers draining one of the largest concentrations of sulphide deposits in the world, the Iberian Pyrite Belt (IPB). Of these rivers, the Guadiana, one of the most important in the Iberian Peninsula, together with smaller rivers like the Tinto and Odiel, delivers a very high metal load to the adjacent coastal areas. The purpose of this work was to study the source and impact of lead (Pb) drained from historical or active mining areas in the IPB on the activity of a Pb inhibited enzyme (δ-aminolevulinic acid dehydratase, ALAD) in several bivalve species along the Gulf of Cadiz. Seven marine species (Chamelea gallina, Mactra corallina, Donax trunculus, Cerastoderma edule, Mytilus galloprovincialis, Scrobicularia plana and Crassostrea angulata) were collected at 12 sites from Mazagon, near the mouth of the rivers Tinto and Odiel (Spain), to Cacela Velha (Ria Formosa lagoon system, Portugal). Lead concentrations, ALAD activity and lead isotope ratios ( 206 Pb/ 204 Pb, 207 Pb/ 204 Pb and 208 Pb/ 204 Pb) were determined in the whole soft tissues. The highest Pb concentrations were determined in S. plana (3.50 ± 1.09 μg g -1 Pb d.w.) and D. trunculus (1.95 ± 0.10 μg g -1 Pb d.w.), while M. galloprovincialis and C. angulata showed the lowest Pb levels ( -1 Pb d.w.). In general, ALAD activity is negatively correlated with total Pb concentration. However this relationship is species dependent (e.g. linear for C. gallina ALAD = -0.36[Pb] + 0.79; r = 0.837; or exponential for M. galloprovincialis ALAD = 2.48e -8.3[Pb] ; r = 0.911). This indicates that ALAD activity has considerable potential as a biomarker of Pb and moreover, in marine bivalve species with different feeding habits. Lead isotope data
Alteration of the phospho- or neutral lipid content and fatty acid composition in Listeria monocytogenes due to acid adaptation mechanisms for hydrochloric, acetic and lactic acids at pH 5.5 or benzoic acid at neutral pH.

Science.gov (United States)

Mastronicolis, Sofia K; Berberi, Anita; Diakogiannis, Ioannis; Petrova, Evanthia; Kiaki, Irene; Baltzi, Triantafillia; Xenikakis, Polydoros

2010-10-01

This study provides a first approach to observe the effects on Listeria monocytogenes of cellular exposure to acid stress at low or neutral pH, notably how phospho- or neutral lipids are involved in this mechanism, besides the fatty acid profile alteration. A thorough investigation of the composition of polar and neutral lipids from L. monocytogenes grown at pH 5.5 in presence of hydrochloric, acetic and lactic acids, or at neutral pH 7.3 in presence of benzoic acid, is described relative to cells grown in acid-free medium. The results showed that only low pH values enhance the antimicrobial activity of an acid. We suggest that, irrespective of pH, the acid adaptation response will lead to a similar alteration in fatty acid composition [decreasing the ratio of branched chain/saturated straight fatty acids of total lipids], mainly originating from the neutral lipid class of adapted cultures. Acid adaptation in L. monocytogenes was correlated with a decrease in total lipid phosphorus and, with the exception of cells adapted to benzoic acid, this change in the amount of phosphorus reflected a higher content of the neutral lipid class. Upon acetic or benzoic acid stress the lipid phosphorus proportion was analysed in the main phospholipids present: cardiolipin, phosphatidylglycerol, phosphoaminolipid and phosphatidylinositol. Interestingly only benzoic acid had a dramatic effect on the relative quantities of these four phospholipids.
The effect of oral administration of Allium sativum extracts on lead nitrate induced toxicity in male mice.

Science.gov (United States)

Sharma, Veena; Sharma, Arti; Kansal, Leena

2010-03-01

Lead is a common environmental occupational toxic metal, known to have indirect oxidative effects. Considering the antioxidant properties of garlic, this study was undertaken to evaluate the therapeutic efficacy of garlic extracts in terms of normalization of altered hematological, biochemical and immunological parameters, and depletion of inorganic lead burden in blood, kidney and brain tissues. Chronic lead nitrate ingestion showed a significant decline in total erythrocyte count, total leukocyte count, hemoglobin concentration, lymphocyte and monocyte content, while neutrophil content increased in lead nitrate treated group. Pb(NO(3))(2) exposure elicited a significant escalation in thiobarbituric acid reactive substances level and depletion in reduced glutathione content and antioxidant enzymes namely, superoxide dismutase and catalase in kidney and brain. Activities of aspartate transaminase, alanine transaminase, acid phosphatase and alkaline phosphatase augmented significantly in kidney and brain of lead exposed mice. Lead nitrate treatment decreased protein content while cholesterol and lead burden increased significantly. A decrease in viability of macrophage, phagocytic index, immunoglobulin level and plaque count were the salient features observed in lead exposed animals. However, oral administration of garlic extracts to Pb(NO(3))(2) treated groups attenuated the deranged parameters to some extent. This indicates that garlic can be a protective regimen for lead toxicity. Copyright (c) 2010 Elsevier Ltd. All rights reserved.
Adaptive alterations in the fatty acids composition under induced oxidative stress in heavy metal-tolerant filamentous fungus Paecilomyces marquandii cultured in ascorbic acid presence.

Science.gov (United States)

Słaba, Mirosława; Gajewska, Ewa; Bernat, Przemysław; Fornalska, Magdalena; Długoński, Jerzy

2013-05-01

The ability of the heavy metal-tolerant fungus Paecilomyces marquandii to modulate whole cells fatty acid composition and saturation in response to IC50 of Cd, Pb, Zn, Ni, and Cu was studied. Cadmium and nickel caused the most significant growth reduction. In the mycelia cultured with all tested metals, with the exception of nickel, a rise in the fatty acid unsaturation was noted. The fungus exposure to Pb, Cu, and Ni led to significantly higher lipid peroxidation. P. marquandii incubated in the presence of the tested metals responded with an increase in the level of linoleic acid and escalation of electrolyte leakage. The highest efflux of electrolytes was caused by lead. In these conditions, the fungus was able to bind up to 100 mg g(-1) of lead, whereas the content of the other metals in the mycelium was significantly lower and reached from 3.18 mg g(-1) (Cu) to 15.21 mg g(-1) (Zn). Additionally, it was shown that ascorbic acid at the concentration of 1 mM protected fungal growth and prevented the changes in the fatty acid composition and saturation but did not alleviate lipid peroxidation or affect the increased permeability of membranes after lead exposure. Pro-oxidant properties of ascorbic acid in the copper-stressed cells manifested strong growth inhibition and enhanced metal accumulation as a result of membrane damage. Toxic metals action caused cellular modulations, which might contributed to P. marquandii tolerance to the studied metals. Moreover, these changes can enhance metal removal from contaminated environment.
Evaluation of lead/carbon devices for utility applications : a study for the DOE Energy Storage Program.

Energy Technology Data Exchange (ETDEWEB)

Walmet, Paula S. (MeadWestvaco Corporation,North Charleston, SC)

2009-06-01

This report describes the results of a three-phase project that evaluated lead-based energy storage technologies for utility-scale applications and developed carbon materials to improve the performance of lead-based energy storage technologies. In Phase I, lead/carbon asymmetric capacitors were compared to other technologies that used the same or similar materials. At the end of Phase I (in 2005) it was found that lead/carbon asymmetric capacitors were not yet fully developed and optimized (cost/performance) to be a viable option for utility-scale applications. It was, however, determined that adding carbon to the negative electrode of a standard lead-acid battery showed promise for performance improvements that could be beneficial for use in utility-scale applications. In Phase II various carbon types were developed and evaluated in lead-acid batteries. Overall it was found that mesoporous activated carbon at low loadings and graphite at high loadings gave the best cycle performance in shallow PSoC cycling. Phase III studied cost/performance benefits for a specific utility application (frequency regulation) and the full details of this analysis are included as an appendix to this report.
Osteoporosis and hydronephrosis of young lambs following the ingestion of lead

Energy Technology Data Exchange (ETDEWEB)

Clegg, F G; Rylands, J M

1966-01-01

Lead poisoning is described in young lambs which were reared near lead mining areas in North Derbyshire, England. A brief history of the poisoning of stock which has occurred in the past near lead workings is given. The clinical results and post-mortem findings are reported together with descriptions of radiographical, histological and biochemical findings. A striking feature of all post-mortem examinations was an emaciated carcase with grossly abnormal kidneys. The bones were fragile and easily broken or cut. Kidney cortex and liver lead estimations were carried out in every case. The response of affected lambs to treatment with ascorbic acid is described and the similarities of the clinical signs and the skeletal lesions to scurvy in man and the guinea pig are discussed. 31 references, 6 figures, 2 tables.
Genetic manipulation of the γ-aminobutyric acid (GABA) shunt in rice: overexpression of truncated glutamate decarboxylase (GAD2) and knockdown of γ-aminobutyric acid transaminase (GABA-T) lead to sustained and high levels of GABA accumulation in rice kernels.

Science.gov (United States)

Shimajiri, Yasuka; Oonishi, Takayuki; Ozaki, Kae; Kainou, Kumiko; Akama, Kazuhito

2013-06-01

Gamma-aminobutyric acid (GABA) is a non-protein amino acid commonly present in all organisms. Because cellular levels of GABA in plants are mainly regulated by synthesis (glutamate decarboxylase, GAD) and catabolism (GABA-transaminase, GABA-T), we attempted seed-specific manipulation of the GABA shunt to achieve stable GABA accumulation in rice. A truncated GAD2 sequence, one of five GAD genes, controlled by the glutelin (GluB-1) or rice embryo globulin promoters (REG) and GABA-T-based trigger sequences in RNA interference (RNAi) cassettes controlled by one of these promoters as well, was introduced into rice (cv. Koshihikari) to establish stable transgenic lines under herbicide selection using pyriminobac. T₁ and T₂ generations of rice lines displayed high GABA concentrations (2-100 mg/100 g grain). In analyses of two selected lines from the T₃ generation, there was a strong correlation between GABA level and the expression of truncated GAD2, whereas the inhibitory effect of GABA-T expression was relatively weak. In these two lines both with two T-DNA copies, their starch, amylose, and protein levels were slightly lower than non-transformed cv. Koshihikari. Free amino acid analysis of mature kernels of these lines demonstrated elevated levels of GABA (75-350 mg/100 g polished rice) and also high levels of several amino acids, such as Ala, Ser, and Val. Because these lines of seeds could sustain their GABA content after harvest (up to 6 months), the strategy in this study could lead to the accumulation GABA and for these to be sustained in the edible parts. © 2013 Society for Experimental Biology, Association of Applied Biologists and John Wiley & Sons Ltd.
Mechanistic study of lead desorption during the leaching process of ion-absorbed rare earths: pH effect and the column experiment.

Science.gov (United States)

Tang, Jie; Xue, Qiang; Chen, Honghan; Li, Wenting

2017-05-01

High concentrations of ammonium sulfate, often used in the in situ mining process, can result in a decrease of pH in the environment and dissolution of rare earth metals. Ammonium sulfate can also cause desorption of toxic heavy metals, leading to environmental and human health implications. In this study, the desorption behavior and fraction changes of lead in the ion-absorbed rare earth ore were studied using batch desorption experiments and column leaching tests. Results from batch desorption experiments showed that the desorption process of lead included fast and slow stages and followed an Elovich model well. The desorption rate and the proportion of lead content in the solution to the total lead in the soil were observed to increase with a decrease in the initial pH of the ammonium sulfate solution. The lead in soil included an acid-extractable fraction, reducible fraction, oxidizable fraction, and a residual fraction, with the predominant fractions being the reducible and acid-extractable fractions. Ninety-six percent of the extractable fraction in soil was desorbed into solution at pH = 3.0, and the content of the reducible fraction was observed to initially increase (when pH >4.0) and then decrease (when pH leaching tests indicated that the content of lead in the different fractions of soil followed the trend of reducible fraction > oxidizable fraction > acid-extractable fraction > residual fraction after the simulating leaching mining process. The change in pH was also found to have a larger influence on the acid-extractable and reducible fractions than the other two fractions. The proportion of the extractable fraction being leached was ca. 86%, and the reducible fraction was enriched along the migration direction of the leaching liquid. These results suggest that certain lead fractions may desorb again and contaminate the environment via acid rain, which provides significant information for environmental assessment and remediation after mining process
Mechanistic study of lead desorption during the leaching process of ion-absorbed rare earths: pH effect and the column experiment

Science.gov (United States)

Xue, Q.; Tang, J., Sr.; Chen, H.

2017-12-01

High concentrations of ammonium sulfate, often used in the in-situ mining process, can result in a decrease of pH in the environment and dissolution of rare earth metals. Ammonium sulfate can also cause desorption of toxic heavy metals, leading to environmental and human health implications. In this study, the desorption behavior and fraction changes of lead in the ion-absorbed rare earth ore were studied using batch desorption experiments and column leaching tests. Results from batch desorption experiments showed that the desorption process of lead included fast and slow stages, and followed an Elovich model well. The desorption rate and the proportion of lead content in the solution to the total lead in the soil were observed to increase with a decrease in the initial pH of the ammonium sulfate solution. The lead in soil included an acid extractable fraction, reducible fraction, oxidizable fraction, and a residual fraction, with the predominant fractions being the reducible and acid extractable fractions. 96% of the extractable fraction in soil were desorbed into solution at pH=3.0, and the content of the reducible fraction was observed to initially increase (when pH>4.0) and then decrease (when pHleaching tests indicated that the content of lead in the different fractions of soil followed the trend of reducible fraction > oxidizable fraction > acid extractable fraction > residual fraction after the simulating leaching mining process. The change in pH was also found to have a larger influence on the acid extractable and reducible fractions than the other two fractions. The proportion of the extractable fraction being leached was ca. 86%, and the reducible fraction was enriched along the migration direction of the leaching liquid. These results suggest that certain lead fractions may desorb again and contaminate the environment via acid rain, which provides significant information for environmental assessment and remediation after mining process.
Influence of lysozyme complexation with purified Aldrich humic acid on lysozyme activity

NARCIS (Netherlands)

Li, Y.; Tan, W.F.; Wang, M.X.; Liu, F.; Weng, L.P.; Norde, W.; Koopal, L.K.

2012-01-01

Humic acid is an important component of dissolved organic matter and in two previous papers it has been shown that purified Aldrich humic acid (PAHA) forms strong complexes with the oppositely charged protein lysozyme (LSZ). The complexation and aggregation of enzymes with humic acids may lead to
Apoptosis and signalling in acid sphingomyelinase deficient cells

Directory of Open Access Journals (Sweden)

Sillence Dan J

2001-11-01

Full Text Available Abstract Background Recent evidence suggests that the activation of a non-specific lipid scramblase during apoptosis induces the flipping of sphingomyelin from the cell surface to the cytoplasmic leaftet of the plasma membrane. Inner leaflet sphingomyelin is then cleaved to ceramide by a neutral sphingomyelinase. The production of this non-membrane forming lipid induces blebbing of the plasma membrane to aid rapid engulfment by professional phagocytes. However contrary evidence suggests that cells which are deficient in acid sphingomyelinase are defective in apoptosis signalling. This data has been interpreted as support for the activation of acid sphingomyelinase as an early signal in apoptosis. Hypothesis An alternative explanation is put forward whereby the accumulation of intracellular sphingomyelin in sphingomyelinase deficient cells leads to the formation of intracellular rafts which lead to the sequestration of important signalling molecules that are normally present on the cell surface where they perform their function. Testing the hypothesis It is expected that the subcellular distribution of important signalling molecules is altered in acid sphingomyelinase deficient cells, leading to their sequestration in late endosomes / lysosomes. Other sphingolipid storage diseases such as Niemann-Pick type C which have normal acid sphingomyelinase activity would also be expected to show the same phenotype. Implications of the hypothesis If true the hypothesis would provide a mechanism for the pathology of the sphingolipid storage diseases at the cellular level and also have implications for the role of ceramide in apoptosis.

Effects of acid deposition on microbial processes in natural waters

International Nuclear Information System (INIS)

Gilmour, C.C.

1992-01-01

Biogeochemical processes mediated by microorganisms are not adversely affected by the acidification of natural waters to the same extent as are the life cycles of higher organisms. Basic processes, e.g., primary production and organic matter decomposition, are not slowed in moderately acidified systems and do not generally decline above a pH of 5. More specifically, the individual components of the carbon, nitrogen, and sulfur cycles are, with few exceptions, also acid resistant. The influence of acid deposition on microbial processes is more often stimulation of nitrogen and sulfur cycling, often leading to alkalinity production, which mitigates the effect of strong acid deposition. Bacterial sulfate reduction and denitrification in sediments are two of the major processes that can be stimulated by sulfate and nitrate deposition, respectively, and result in ANC (acid-neutralizing capacity) generation. One of the negative effects of acid deposition is increased mobilization and bioaccumulation of some metals. Bacteria appear to play an important role, especially in mercury cycling, with acidification leading to increased bacterial methylation of mercury and subsequent bioaccumulation in higher organisms
Determination of lead at nanogram level in water samples by ...

African Journals Online (AJOL)

A novel method of chemistry applicable to the determination of trace lead in water samples based on the resonance light scattering (RLS) technique has been developed. In dilute phosphoric acid medium, in the presence of a large excess of I-, Pb(II) can form [PbI4]2-, which further reacts with tetrabutyl ammonium bromide ...
Folic acid fortification and public health: Report on threshold doses above which unmetabolised folic acid appear in serum

Directory of Open Access Journals (Sweden)

McPartlin Joseph

2007-03-01

Full Text Available Abstract Background All flour in the USA is fortified with folic acid at a level of 140 μg/100 g which is estimated to supply an extra 100 μg daily to the average diet. Some researchers have advocated that this be increased to double and even four times this amount. Based on previous research these higher levels are likely to lead to the appearance of unmetabolised vitamin in the circulation, which may have safety implications for sub-groups of the population. The UK and the Republic of Ireland will likely introduce mandatory fortification also in the next year or so. The aim of this study was to capture the short-term effect of folic acid fortification on unmetabolised folic acid in serum after chronic consumption of folic acid. Methods After pre-saturation with 400 μg folic acid supplements daily for 14-weeks, healthy folate replete adults (n = 20 consumed folic acid fortified bread, at three different levels (400 μg, 200 μg, 100 μg over a period of one week each. The dose was administered in two-equal sized slices consumed at 09.00 hrs and 13.00 hrs. Serum samples for total folate and folic acid were collected at baseline, after 14-weeks of supplementation, and pre and post (at 1, 2, 3 and 4 hours each dose tested. Results Unmetabolised folic acid was detected after the 14-week supplementation period. Folic acid was not detected in either the 200 μg or 100 μg (current US regime doses tested but was present at the highest level (400 μg tested. Conclusion Our findings suggest that persons exposed to the current US fortification programme supplying an average of 100 μg per day or less are unlikely to have unmetabolised folic acid in serum. It also seems that daily consumption of the higher level of 200 μg or less is unlikely to be problematic. Increasing the level however to 400 μg on the other hand is likely to lead to unmetabolised folic acid appearance.
Aerosol Fragmentation Driven by Coupling of Acid-Base and Free-Radical Chemistry in the Heterogeneous Oxidation of Aqueous Citric Acid by OH Radicals.

Science.gov (United States)

Liu, Matthew J; Wiegel, Aaron A; Wilson, Kevin R; Houle, Frances A

2017-08-10

A key uncertainty in the heterogeneous oxidation of carboxylic acids by hydroxyl radicals (OH) in aqueous-phase aerosol is how the free-radical reaction pathways might be altered by acid-base chemistry. In particular, if acid-base reactions occur concurrently with acyloxy radical formation and unimolecular decomposition of alkoxy radicals, there is a possibility that differences in reaction pathways impact the partitioning of organic carbon between the gas and aqueous phases. To examine these questions, a kinetic model is developed for the OH-initiated oxidation of citric acid aerosol at high relative humidity. The reaction scheme, containing both free-radical and acid-base elementary reaction steps with physically validated rate coefficients, accurately predicts the experimentally observed molecular composition, particle size, and average elemental composition of the aerosol upon oxidation. The difference between the two reaction channels centers on the reactivity of carboxylic acid groups. Free-radical reactions mainly add functional groups to the carbon skeleton of neutral citric acid, because carboxylic acid moieties deactivate the unimolecular fragmentation of alkoxy radicals. In contrast, the conjugate carboxylate groups originating from acid-base equilibria activate both acyloxy radical formation and carbon-carbon bond scission of alkoxy radicals, leading to the formation of low molecular weight, highly oxidized products such as oxalic and mesoxalic acid. Subsequent hydration of carbonyl groups in the oxidized products increases the aerosol hygroscopicity and accelerates the substantial water uptake and volume growth that accompany oxidation. These results frame the oxidative lifecycle of atmospheric aerosol: it is governed by feedbacks between reactions that first increase the particle oxidation state, then eventually promote water uptake and acid-base chemistry. When coupled to free-radical reactions, acid-base channels lead to formation of low molecular
The Roles of Acids and Bases in Enzyme Catalysis

Science.gov (United States)

Weiss, Hilton M.

2007-01-01

Many organic reactions are catalyzed by strong acids or bases that protonate or deprotonate neutral reactants leading to reactive cations or anions that proceed to products. In enzyme reactions, only weak acids and bases are available to hydrogen bond to reactants and to transfer protons in response to developing charges. Understanding this…
The synthesis of glutamic acid in the absence of enzymes: Implications for biogenesis

Science.gov (United States)

Morowitz, Harold; Peterson, Eta; Chang, Sherwood

1995-01-01

This paper reports on the non-enzymatic aqueous phase synthesis of amino acids from keto acids, ammonia and reducing agents. The facile synthesis of key metabolic intermediates, particularly in the glycolytic pathway, the citric acid cycle, and the first step of amino acid synthesis, lead to new ways of looking at the problem of biogenesis.
Determination of strontium and lead isotope ratios of grains using high resolution inductively coupled plasma mass spectrometer with single collector

International Nuclear Information System (INIS)

Shinozaki, Miyuki; Ariyama, Kaoru; Kawasaki, Akira; Hirata, Takafumi

2010-01-01

A method for determining strontium and lead isotope ratios of grains was developed. The samples investigated in this study were rice, barley and wheat. The samples were digested with nitric acid and hydrogen peroxide, and heated in a heating block. Strontium and lead were separated from the matrix by adding an acid digested solution into a column packed with Sr resin, which has selectivity for the absorption of strontium and lead. Strontium and lead isotope ratios were determined using a high-resolution inductively coupled plasma mass spectrometer (HR-ICP-MS) with a single collector. The intraday relative standard deviations of 87 Sr/ 86 Sr and lead isotope ratios ( 204 Pb/ 206 Pb, 207 Pb/ 206 Pb, 208 Pb/ 206 Pb) by HR-ICP-MS measurements were < 0.06% and around 0.1%, respectively. This method enabled us to determine strontium and lead isotope ratios in two days. (author)
Synthesis and pharmacology of 3-isoxazolol amino acids as selective antagonists at group I metabotropic glutamic acid receptors

DEFF Research Database (Denmark)

Madsen, U; Bräuner-Osborne, H; Frydenvang, Karla Andrea

2001-01-01

Using ibotenic acid (2) as a lead, two series of 3-isoxazolol amino acid ligands for (S)-glutamic acid (Glu, 1) receptors have been developed. Whereas analogues of (RS)-2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid [AMPA, (RS)-3] interact selectively with ionotropic Glu receptors (i......GluRs), the few analogues of (RS)-2-amino-3-(3-hydroxy-5-isoxazolyl)propionic acid [HIBO, (RS)-4] so far known typically interact with iGluRs as well as metabotropic Glu receptors (mGluRs). We here report the synthesis and pharmacology of a series of 4-substituted analogues of HIBO. The hexyl analogue 9 was shown...... to originate in (S)-11 (EC(50) = 395 microM, K(b) = 86 and 90 microM, respectively). Compound 9, administered icv, but not sc, was shown to protect mice against convulsions induced by N-methyl-D-aspartic acid (NMDA). Compounds 9 and 11 were resolved using chiral HPLC, and the configurational assignments...
Lead-acid and lithium-ion batteries for the Chinese electric bike market and implications on future technology advancement

International Nuclear Information System (INIS)

Weinert, Jonathan X.; Burke, Andrew F.; Wei, Xuezhe

2007-01-01

China has been experiencing a rapid increase in battery-powered personal transportation since the late 1990s due to the strong growth of the electric bike and scooter (i.e. e-bike) market. Annual sales in China reached 17 million bikes year -1 in 2006. E-bike growth has been in part due to improvements in rechargeable valve-regulated lead-acid (VRLA) battery technology, the primary battery type for e-bikes. Further improvements in technology and a transition from VRLA to lithium-ion (Li-ion) batteries will impact the future market growth of this transportation mode in China and abroad. Battery performance and cost for these two types are compared to assess the feasibility of a shift from VRLA to Li-ion battery e-bikes. The requirements for batteries used in e-bikes are assessed. A widespread shift from VRLA to Li-ion batteries seems improbable in the near future for the mass market given the cost premium relative to the performance advantages of Li-ion batteries. As both battery technologies gain more real-world use in e-bike applications, both will improve. Cell variability is a key problematic area to be addressed with VRLA technology. For Li-ion technology, safety and cost are the key problem areas which are being addressed through the use of new cathode materials. (author)
N-cinnamoylated chloroquine analogues as dual-stage antimalarial leads.

Science.gov (United States)

Pérez, Bianca C; Teixeira, Cátia; Albuquerque, Inês S; Gut, Jiri; Rosenthal, Philip J; Gomes, José R B; Prudêncio, Miguel; Gomes, Paula

2013-01-24

The control of malaria is challenged by drug resistance, and new antimalarial drugs are needed. New drug discovery efforts include consideration of hybrid compounds as potential multitarget antimalarials. Previous work from our group has demonstrated that hybrid structures resulting from cinnamic acid conjugation with heterocyclic moieties from well-known antimalarials present improved antimalarial activity. Now, we report the synthesis and SAR analysis of an expanded series of cinnamic acid derivatives displaying remarkably high activities against both blood- and liver-stage malaria parasites. Two compounds judged most promising, based on their in vitro activity and druglikeness according to the Lipinski rules and Veber filter, were active in vivo against blood-stage rodent malaria parasites. Therefore, the compounds reported represent a new entry as promising dual-stage antimalarial leads.
Study of the influence of carbon on the negative lead-acid battery electrodes

Czech Academy of Sciences Publication Activity Database

Bača, P.; Micka, Karel; Křivík, P.; Tonar, K.; Tošer, P.

2011-01-01

Roč. 196, č. 8 (2011), s. 3988-3992 ISSN 0378-7753 Institutional research plan: CEZ:AV0Z40400503 Keywords : lead battery electrodes * doping with carbon * accelerated testing Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 4.951, year: 2011
Production of Citric Acid from Solid State Fermentation of Sugarcane ...

African Journals Online (AJOL)

Aspergillus niger is the leading microorganism of choice for citric acid production. Sugarcane waste was used as substrate under solid state fermentation to comparatively evaluate the citric acid production capacity of Aspergillus niger isolates and the indigenous microflora in the sugarcane waste. Known optimal cultural ...
Quantum confinement effects on superconducting properties of Lead nanocrystals

Science.gov (United States)

Aubin, Herve; Moreira, Helena; Mahler, Benoit; Dubertret, Benoit

2008-03-01

We developed a new chemical synthesis method for producing large quantities of monodispersed lead (Pb) nanocrystals. They are obtained from the alcohol reduction of a mixture of two lead carboxylates with alkyl chains of different lengths, dissolved in a high temperature solvent. The nanocrystals obtained are protected from oxydation and aggregation by long chain fatty acids and their diameter can be tuned to reach values as low as 10 nm. Our results suggest that monodispersed particules are obtained when nucleation and growth occur at distincts temperatures, possibly as a consequence of different reactivities of the two lead carboxylates used in the solution. Owing to the large quantities of monodispersed particles produced, thermodynamics studies as function of particles diameter become possible. In particular, we will present a study of the effect of quantum confinement on superconducting properties of these Pb particles through SQUID magnetometry measurements.
Thermodynamic analysis of separating lead and antimony in chloride system

Institute of Scientific and Technical Information of China (English)

CHEN Jin-zhong; CAO Hua-zhen; LI Bo; YUAN Hai-jun; ZHENG Guo-qu; YANG Tian-zu

2009-01-01

In chloride system, thermodynamic analysis is a useful guide to separate lead and antimony as well as to understand the separation mechanism. An efficient and feasible way for separating lead and antimony was discussed. The relationships of [Pb2+][Cl-]2-lg[Cl]T and E-lg[Cl]T in Pb-Sb-Cl-H2O system were studied, and the solubilities of lead chloride at different antimony concentrations were calculated based on principle of simultaneous equilibrium. The results show that insoluble salt PbCl2 will only exist stably in a certain concentration range of chlorine ion. This concentration range of chlorine ion expands a little with increasing the concentration of antimony in the system while narrows as the system acidity increases. The solubility of Pb2+ in solution decreases with increasing the concentration of antimony in the system, whereas increases with increasing the concentration of total chlorine. The concentration range of total chlorine causing lead solubility less than 0.005 mol/L increases monotonically.
In vivo x-ray fluorescence of bone lead in the study of human lead metabolism: Serum lead, whole blood lead, bone lead, and cumulative exposure

International Nuclear Information System (INIS)

Cake, K.M.; Chettle, D.R.; Webber, C.E.; Gordon, C.L.

1995-01-01

Traditionally, clinical studies of lead's effect on health have relied on blood lead levels to indicate lead exposure. However, this is unsatisfactory because blood lead levels have a half-life of approximately 5 weeks, and thus reflect recent exposure. Over 90% of the lead body burden is in bone, and it is thought to have a long residence time, thus implying that measurements of bone lead reflect cumulative exposure. So, measurements of bone lead are useful in understanding the long-term health effects of lead. Ahlgren reported the first noninvasive measurements of bone lead in humans, where γ-rays from 57 Co were used to excite the K series x-rays of lead. The lead detection system at McMaster University uses a 109 Cd source which is positioned at the center of the detector face (HPGe) and a near backscatter (∼160 degrees) geometry. This arrangement allows great flexibility, since one can sample lead in a range of different bone sites due to a robust normalization technique which eliminates the need to correct for bone geometry, thickness of overlying tissue, and other related factors. The effective radiation dose to an adult during an x-ray fluorescence bone lead measurement is extremely low, being 35 nSv. This paper addresses the issue of how bone, whole blood, and serum lead concentrations can be related in order to understand a person's lead exposure history
Cellular location of lead and potassium in the lichen Cladonia rangiformis (L. ) Hoffm

Energy Technology Data Exchange (ETDEWEB)

Brown, D H; Slingsby, D R

1972-01-01

The cellular location of lead and potassium has been studied in the lichen Cladonia rangiformis, collected from a lead-rich site. Elution of ions by dilute acid or their replacement by other ions has demonstrated that lead is ionically bound, most probably within the cell wall. The same techniques have shown a proportion of the total potassium to be also bound ionically in the cell wall. In addition potassium is present as freely diffusible material retained within the permeability barriers of the intact cell and also firmly bound in an insoluble form. The reported tolerance of lichens to heavy metal is discussed in relation to the demonstrated location of lead. 9 references, 2 figures, 1 table.
Genomic study of the absorption mechanism of p-coumaric acid and caffeic acid of extract of Ananas comosus L. leaves.

Science.gov (United States)

Dang, Yun-jie; Zhu, Chun-yan

2015-03-01

Cardiac disease has emerged as the leading cause of death worldwide, and food rich in phenolic acids has drawn much attention as sources of active substances of hypolipidemic drug. Ananas comosus L. (pineapple) is one of the most popular tropical and subtropical fruits. Isolated from pineapple leaves, EAL(Extract of Ananas Comosus L. Leaves) is rich in phenolic acids, such as p-coumaric acid, caffeic acid, and other phenolics, highly relevant to the putative cardiovascular-protective effects, which suggests its potential to be a new plant medicine for treatment of cardiac disease, but little is known about absorption, distribution, metabolism, and excretion of EAL in animals or human beings. In this study, we employed cDNA microarray, Caco-2 cell lines, and rat intestinal model to explore the absorption behavior of p-coumaric acid and caffeic acid in EAL. The permeation of 2 substances was concentration and time dependent. Results also indicated that monocarboxylic acid transporter was involved in the transepithelial transport of p-coumaric acid and caffeic acid. © 2015 Institute of Food Technologists®
Lead uptake from soils by perennial ryegrass and its relation to the supply of an essential element (sulfur)

Energy Technology Data Exchange (ETDEWEB)

Jones, L.H.P.; Jarvis, S.C.; Cowling, D.W.

1973-06-01

The lead status of 16 soils of England and Wales was studied by pot-culture and soil chemical procedures. Perennial ryegrass was grown on the soils, with and without added sulfur, in a controlled environment cabinet with carbon-filtered air. Plant-available lead comprised uptake in 4 successive harvests of tops plus that in roots at the final harvest. The concentration of lead in the tops of healthy plants, those with adequate sulfur, was lower than in the roots, e.g., at harvest 4 the means were 5.0 and 12.9 ppm, respectively. However, with sulfur-deficient plants the concentration of lead in the tops was often higher than in the roots, the means at harvest 4 being 16.3 and 13.0 ppm respectively. The marked increases in the concentration of lead in the tops of sulfur-deficient plants coincided with decreases in dry-matter yield, but for any one soil the tops of such plants contained similar amounts of lead to those of healthy plants. The led content of the tops was poorly correlated with soil lead whereas that of the roots, in terms of both concentration and total amount, was highly correlated. The amount of lead extracted by 0.5 M BaCl/sub 2/ or 0.05 M EDTA provided a slightly better assessment of availability than total content or the amount extracted by 2.5 percent acetic acid. The solutions of acetic acid, BaCl/sub 2/ and EDTA extracted, on average, 1.0, 16.3 and 32.7 per cent respectively of the total lead in the soils. The greater replacement of lead by the Ba ion than by the H ion (acetic acid) is ascribed to valence and the similar radii of Pb/sup 2 +/ and Ba/sup 2 +/. It is concluded that in soil-grown ryegrass the roots restrict the movement of lead into the tops of high-yielding plants, but when growth is limited by sulfur deficiency the concentration in the tops increases markedly.
Electrochemical stripping determination of traces of copper, lead, cadmium and zinc in zirconium metal and zirconium dioxide

International Nuclear Information System (INIS)

Stulik, K.; Beran, P.; Dolezal, J.; Opekar, F.

1978-01-01

Procedures have been developed for the determination of copper, lead, cadmium and zinc in zirconium metal and zirconium dioxide, at concentrations of 1ppm or less. Zirconium metal was dissolved in sulphuric acid, and zirconium dioxide decomposed under pressure with hydrofluoric acid. Sample solutions were prepared in dilute sulphuric acid. For the stripping determination, the sample solution was either mixed with a complexing tartrate base electrolyte or the pre-electrolysis was carried out in acid solution, with the acid solution being exchanged for a pure base electrolyte (e.g. an acetate buffer) for the stripping step. The stripping step was monitored by d.c., differential pulse and Kalousek commutator voltammetry and the three methods were compared. A stationary mercury-drop electrode can generally be used for all the methods, whereas a mercury-film electrode is suitable only for the d.c. voltammetric determination of copper, lead and cadmium, as pulse measurements with films are poorly reproducible and the electrodes are easily damaged. The relative standard deviation does not exceed 20%. Some samples contained relatively large amounts of copper, which is best separated by electrodeposition on a platinum electrode. (author)
Toxic effect evaluation of the lead acetate and chromium chloride on anaerobic bacterial metabolism

International Nuclear Information System (INIS)

Wills, Beatriz; Naranjo, Fernando

2004-01-01

The toxicity of trivalent chromium and lead to anaerobic sludge system was studied. Performed assay was tested in 60 mL serum vials, the toxicity test to succeed in two steps, first with formic acid and then whey powder as a substrate. Anaerobic toxicity assays were performed taking into account, methane gas production and oxidation-reduction potential (ORP) rate, these tests were considered a useful indicator for monitoring a anaerobic sludge suffering from toxicants, over 72 hours with metals dosage against the control. First of all, exploratory assays in order to know different chromium and lead concentrations were carried out. The assays degradation activity reduced methane by 50% that came into contact with 3.322 mg Cr 3 +/L and 1.415 mg Pb/L and 2.291 mg Cr 3 +/Land 1.982 mg Pb/L with formic acid and whey powder as a substrate respectively. Heavy metal concentrations that caused 50% inhibition of methanogenesis during whey and formic acid methanation indicated that toxicity decreased in order Pb>>Cr

Do fatty acids affect fetal programming?

Science.gov (United States)

Kabaran, Seray; Besler, H Tanju

2015-08-13

In this study discussed the primary and regulatory roles of fatty acids, and investigated the affects of fatty acids on metabolic programming. Review of the literature was carried out on three electronic databases to assess the roles of fatty acids in metabolic programming. All abstracts and full-text articles were examined, and the most relevant articles were selected for screening and inclusion in this review. The mother's nutritional environment during fetal period has important effects on long term health. Fatty acids play a primary role in growth and development. Alterations in fatty acid intake in the fetal period may increase the risk of obesity and metabolic disorders in later life. Maternal fatty acid intakes during pregnancy and lactation are passed to the fetus and the newborn via the placenta and breast milk, respectively. Imbalances in fatty acid intake during the fetal period change the fatty acid composition of membrane phospholipids, which can cause structural and functional problems in cells. Additionally, the metabolic and neuroendocrine environments of the fetus and the newborn play key roles in the regulation of energy balance. Imbalances in fatty acid intake during pregnancy and lactation may result in permanent changes in appetite control, neuroendocrine function and energy metabolism in the fetus, leading to metabolic programming. Further studies are needed to determine the role of fatty acid intake in metabolic programming.
Single amino acid change in STING leads to constitutive active signaling.

Directory of Open Access Journals (Sweden)

Eric D Tang

Full Text Available The production of cytokines by the immune system in response to cytosolic DNA plays an important role in host defense, autoimmune disease, and cancer immunogenicity. Recently a cytosolic DNA signaling pathway that is dependent on the endoplasmic reticulum adaptor and cyclic dinucleotide sensor protein STING has been identified. Association of cytosolic DNA with cyclic-GMP-AMP synthase (cGAS activates its enzymatic activity to synthesize the cyclic dinucleotide second messenger cGAMP from GTP and ATP. Direct detection of cGAMP by STING triggers the activation of IRF3 and NF-kB, and the production of type I interferons and proinflammatory cytokines. The mechanism of how STING is able to mediate downstream signaling remains incompletely understood although it has been shown that dimerization is a prerequisite. Here, we identify a single amino acid change in STING that confers constitutive active signaling. This mutation appears to both enhance ability of STING to both dimerize and associate with its downstream target TBK1.
Single amino acid change in STING leads to constitutive active signaling.

Science.gov (United States)

Tang, Eric D; Wang, Cun-Yu

2015-01-01

The production of cytokines by the immune system in response to cytosolic DNA plays an important role in host defense, autoimmune disease, and cancer immunogenicity. Recently a cytosolic DNA signaling pathway that is dependent on the endoplasmic reticulum adaptor and cyclic dinucleotide sensor protein STING has been identified. Association of cytosolic DNA with cyclic-GMP-AMP synthase (cGAS) activates its enzymatic activity to synthesize the cyclic dinucleotide second messenger cGAMP from GTP and ATP. Direct detection of cGAMP by STING triggers the activation of IRF3 and NF-kB, and the production of type I interferons and proinflammatory cytokines. The mechanism of how STING is able to mediate downstream signaling remains incompletely understood although it has been shown that dimerization is a prerequisite. Here, we identify a single amino acid change in STING that confers constitutive active signaling. This mutation appears to both enhance ability of STING to both dimerize and associate with its downstream target TBK1.
Capillary microreactors for lactic acid extraction: experimental and modelling study

NARCIS (Netherlands)

Susanti, Susanti; Winkelman, Jozef; Schuur, Boelo; Heeres, Hero; Yue, Jun

2015-01-01

Lactic acid is an important biobased chemical and, among others, is used for the production of poly-lactic acid. Down-stream processing using state of the art technology is energy intensive and leads to the formation of large amounts of salts. In this presentation, experimental and modeling studies
Fatty acids labelled in the. omega. -position with iodine isotopes

Energy Technology Data Exchange (ETDEWEB)

Mathieu, J.P.; Busquet, G.; Comet, M. (Universite Scientifique et Medicale de Grenoble, 38 - La Tronche (France)); Riche, F.; Vidal, M. (Laboratoire d' Etudes Dynamiques et Structurales de la Selectivite, 38 - Grenoble (France)); Coornaert, S.; Bardy, A. (CEA, Centre de Saclay, 91 - Gif-sur-Yvette (France)); Godart, J. (Institut des Sciences Nucleaires, 38 - Grenoble (France))

1982-01-01

The synthesis of saturated acetylenic and olefinic (Z or E) ..omega..-iodinated fatty acids has been carried out and their labelling with iodine-131 or 123 by exchange I/sup -/, *I/sup -/ has been studied. The influence of several parameters -water and fatty acid concentrations, specific activity, labelling solution acidity, iodine carrier presence- on this exchange reaction has been noted, enabling experimental conditions to be defined that produce labelling yields of greater than 95%. These results should lead to widespread clinical use of iodine labelled fatty acids.
[Remediation efficiency of lead-contaminated soil at an industrial site by ultrasonic-assisted chemical extraction].

Science.gov (United States)

Wang, Xin-jie; Huang, Jin-lou; Liu, Zhi-qiang; Yue, Xi

2013-09-01

This research chose five lead-contaminated sites of a lead-acid battery factory to analyze the speciation distribution and concentration of lead. Under the same conditions (0.1 mol x L(-1) EDTA,30 min, 25 degrees C), the removal effect of heavy metal was compared between ultrasonic-assisted chemical extraction (UCE) and conventional chemical extraction ( CCE), and the variation of lead speciation was further explored. The results showed that the lead removal efficiency of UCE was significantly better than CCE. The lead removal efficiency of WS, A, B, C and BZ was 10.06%, 48.29%, 48.69%, 53.28% and 36.26% under CCE. While the removal efficiency of the UCE was 22.42%, 69.31%, 71.00%, 74.49% and 71.58%, with the average efficiency higher by 22%. By comparing the speciation distribution of the two washing methods, it was found that the acid extractable content maintained or decreased after UCE, whereas it showed an increasing trend after CCE. The reduction effect of the reducible was as high as 98% by UCE. UCE also showed a more efficient reduction effect of the organic matter-sulfite bounded form and the residual form. Hence, it is feasible to improve the washing efficiency of heavy metal contained in soil by conducting the cleaning process with the help of ultrasonic wave, which is a simple and fast mean to remove lead from contaminated sites.
Towards Sustainable Production of Formic Acid.

Science.gov (United States)

Bulushev, Dmitri A; Ross, Julian R H

2018-03-09

Formic acid is a widely used commodity chemical. It can be used as a safe, easily handled, and transported source of hydrogen or carbon monoxide for different reactions, including those producing fuels. The review includes historical aspects of formic acid production. It briefly analyzes production based on traditional sources, such as carbon monoxide, methanol, and methane. However, the main emphasis is on the sustainable production of formic acid from biomass and biomass-derived products through hydrolysis and oxidation processes. New strategies of low-temperature synthesis from biomass may lead to the utilization of formic acid for the production of fuel additives, such as methanol; upgraded bio-oil; γ-valerolactone and its derivatives; and synthesis gas used for the Fischer-Tropsch synthesis of hydrocarbons. Some technological aspects are also considered. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Modification of Aliphatic Petroleum Resin by Peracetic Acid

OpenAIRE

Bondaletov, Vladimir Grigoryevich; Bondaletova, Lyudmila Ivanovna; Hamlenko, A.; Bondaletov, Oleg Vladimirovich; Starovoit, M.

2014-01-01

This work demonstrates the possibility of obtaining modified aliphatic resin (PRC5) by means of petroleum resin oxidation by peracetic acid. We have experimentally determined oxidation conditions that lead to producing resin with maximum epoxy and acid numbers. Ratio of "oxidative system: PRC5" is 0.5:1, process duration is 2 hours. The modified resin structure is determined by IR and NMR spectroscopy.
L-Altruronic acid formed by epimerization of D-galacturonic acid methyl esters during saponification of citrus pectin.

Science.gov (United States)

Zhan, D; Qiu, F; Mort, A J

2001-02-15

While searching for oligosaccharides containing rhamnose residues in the endopolygalacturonase (EPG) digest of saponified citrus pectin, we found several oligomers containing, in addition to galacturonic acid, a sugar previously unreported in pectin. The 1- and 2-D 1H NMR spectra of the oligosaccharides were consistent with the sugar being a uronic acid with its 2- and 3-hydroxyls being axial and 4-hydroxyl being equatorial. MALDI-TOF mass spectrometry indicated that the oligomers consisted solely of uronic acids. Reduction of the uronic acids in the oligosaccharides converted them to galactose and altrose. The altrose was found to be the L enantiomer by comparison of its trimethylsilyl (-)-2-butyl glycosides to those of authentic D-altrose and a racemic mixture. The sugar was not found in oligosaccharides prepared from EPG digestion of citrus pectin deesterified with pectin methylesterase rather than saponification. Thus, it appears that during saponification, a small proportion of the methylesterified galacturonic acid residues in pectins is epimerized at C-5 leading to formation of L-altruronic acid residues.
Lead Poisoning at an Indoor Firing Range.

Science.gov (United States)

Kang, Kyung Wook; Park, Won Ju

2017-10-01

In March 2014, a 39-year-old Korean male presented with a 6-month history of various nonspecific symptoms including dizziness, fatigue, asthenia, irritability, elevated blood pressure, palpitation, eyestrain, and tinnitus. His occupational history revealed that he had been working as an indoor firing range manager for 13 months; therefore, he was subjected to a blood lead level (BLL) test. The test results showed a BLL of 64 μg/dL; hence, he was diagnosed with lead poisoning and immediately withdrawn from work. As evident from the workplace environmental monitoring, the level of lead exposure in the air exceeded its limit (0.015-0.387 mg/m³). He received chelation treatment with calcium-disodium ethylenediaminetetraacetic acid (1 g/day) for 5 days without any adverse effects. In the follow-up results after 2 months, the BLL had decreased to 9.7 μg/dL and the symptoms resolved. This report represents the first occupational case of lead poisoning in firing ranges in Korea, and this necessitates institutional management to prevent the recurrence of poisoning through this route. Workplace environmental monitoring should be implemented for indoor firing ranges, and the workers should undergo regularly scheduled special health examinations. In clinical practice, it is essential to question the patient about his occupational history. © 2017 The Korean Academy of Medical Sciences.
Bile acids for primary sclerosing cholangitis

DEFF Research Database (Denmark)

Poropat, Goran; Giljaca, Vanja; Stimac, Davor

2011-01-01

Primary sclerosing cholangitis is a progressive chronic cholestatic liver disease that usually leads to the development of cirrhosis. Studies evaluating bile acids in the treatment of primary sclerosing cholangitis have shown a potential benefit of their use. However, no influence on patients...
Neurobehavioural and Neurotoxic Effects of L-ascorbic Acid and L ...

African Journals Online (AJOL)

Background: Lead is an environmental toxicant, occupational and environmental exposures remain a serious problem in developing and industrializing countries. Objective: This study is designed to investigate the effects of L-ascorbic acid and L-tryptophan on the neurotoxicity and neurobehavioural alterations in lead ...
Lead Contamination and Source Characterization in Soils Around a Lead-Zinc Smelting Plant in a Near-Urban Environment in Baoji, China.

Science.gov (United States)

Deng, Wenbo; Li, Xuxiang; An, Zhisheng; Yang, Liu

2016-11-01

Economic reforms in China since 1978 have promoted nationwide socioeconomic advancement but led to a considerable amount of environmental pollution. The distribution and sources of Pb in a typical peri-urban industrial part of Baoji, China, were assessed by determining the Pb contents and isotopic compositions in 52 topsoil samples from the study area. The topsoil samples were polluted averagely with 40.88 mg Pb kg -1 , was 1.86 times higher than the Pb content of local background soil (22.04 mg kg -1 ). Pb isotopic compositions were determined by analyzing samples prepared using total digestion and acid extraction methods. Radiogenic isotopes contributed more to the Pb concentrations in the acid extracts than in the total digests. This was shown by the 207/206 Pb and 208/206 Pb ratios, which were 0.845-0.88 and 2.088-2.128, respectively, in the acid extracts and 0.841-0.875 and 2.086-2.125, respectively, in the total digests. This indicates that anthropogenic sources of Pb could be identified more sensitively in acid extracts than in total digests. The Pb isotope ratios showed that burning coal and smelting ore are the predominant anthropogenic sources of Pb in the study area, i.e., a lead-zinc smelter and a coking plant are major sources of Pb in the study area.
Aeration-Controlled Formation of Acid in Heterolactic Fermentations

DEFF Research Database (Denmark)

Adler-Nissen, Jens

1994-01-01

fermentation processes should be analyzed as fed-batch fermentations with oxygen as the limiting substrate. Addition of fructose in limited amounts leads to the formation of one half mole of acetic acid for each mole fructose, thus offering an alternative mechanism for controlling acetic acid formation.......Controlled aeration of Leuconostoc mesenteroides was studied as a possible mechanism for control of the formation of acetic acid, a metabolite of major influence on the taste of lactic fermented foods. Fermentations were carried out in small scale in a medium in which growth was limited...... by the buffer capacity only. Ethanol and acetic acid formed during the fermentation were analyzed by rapid head space gas chromatography, and the ratio of the molar concentrations of these two volatiles quantitatively predicted the balance between the formation of acetic acid and lactic acid. The oxygen...
In Vitro Investigation of Self-Assembled Nanoparticles Based on Hyaluronic Acid-Deoxycholic Acid Conjugates for Controlled Release Doxorubicin: Effect of Degree of Substitution of Deoxycholic Acid

Directory of Open Access Journals (Sweden)

Wen-Hao Wei

2015-03-01

Full Text Available Self-assembled nanoparticles based on a hyaluronic acid-deoxycholic acid (HD chemical conjugate with different degree of substitution (DS of deoxycholic acid (DOCA were prepared. The degree of substitution (DS was determined by titration method. The nanoparticles were loaded with doxorubicin (DOX as the model drug. The human cervical cancer (HeLa cell line was utilized for in vitro studies and cell cytotoxicity of DOX incorporated in the HD nanoparticles was accessed by the 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay. In addition, cellular uptake of fluorescently labeled nanoparticles was also investigated. An increase in the degree of deoxycholic acid substitution reduced the size of the nanoparticles and also enhanced their drug encapsulation efficiency (EE, which increased with the increase of DS. A higher degree of deoxycholic acid substitution also lead to a lower release rate and an initial burst release of doxorubicin from the nanoparticles. In summary, the degree of substitution allows the modulation of the particle size, drug encapsulation efficiency, drug release rate, and cell uptake efficiency of the nanoparticles. The herein developed hyaluronic acid-deoxycholic acid conjugates are a good candidate for drug delivery and could potentiate therapeutic formulations for doxorubicin–mediated cancer therapy.
Amino Acid Catabolism in Alzheimer’s Disease Brain: Friend or Foe?

Directory of Open Access Journals (Sweden)

Jeddidiah W. D. Griffin

2017-01-01

Full Text Available There is a dire need to discover new targets for Alzheimer’s disease (AD drug development. Decreased neuronal glucose metabolism that occurs in AD brain could play a central role in disease progression. Little is known about the compensatory neuronal changes that occur to attempt to maintain energy homeostasis. In this review using the PubMed literature database, we summarize evidence that amino acid oxidation can temporarily compensate for the decreased glucose metabolism, but eventually altered amino acid and amino acid catabolite levels likely lead to toxicities contributing to AD progression. Because amino acids are involved in so many cellular metabolic and signaling pathways, the effects of altered amino acid metabolism in AD brain are far-reaching. Possible pathological results from changes in the levels of several important amino acids are discussed. Urea cycle function may be induced in endothelial cells of AD patient brains, possibly to remove excess ammonia produced from increased amino acid catabolism. Studying AD from a metabolic perspective provides new insights into AD pathogenesis and may lead to the discovery of dietary metabolite supplements that can partially compensate for alterations of enzymatic function to delay AD or alleviate some of the suffering caused by the disease.
Lead concentrations and reproduction in highway-nesting barn swallows

Science.gov (United States)

Grue, C.E.; O'Shea, T.J.; Hoffman, D.J.

1984-01-01

Swallows (Hirundo rustica) collected within the right-of-way of a major Maryland highway were greater than those found in Barn Swallows nesting within a rural area. Lead concentrations in the feathers of adults from the highway colony were also greater than Lead concentrations in the carcasses and stomach contents of adult and nestling Barn those of rural adults, but concentrations in the feathers of nestlings from the two locations were similar. Activity of u-aminolevulinic acid dehydratase in red blood cells was lower in highway-nesting adults and their young than in their rural counterparts, although hemoglobin concentrations and hematocrits did not differ. The number of eggs, nestlings, and body weights of the latter at 16-18 days of age were similar in the two colonies, as were body weights of adults from the two areas. These results suggest that contamination of roadside habitats by lead from automotive emissions does not pose a serious hazard to birds that are aerial feeders.
Exopolysaccharides produced by lactic acid bacteria

NARCIS (Netherlands)

Caggianiello, Graziano; Kleerebezem, Michiel; Spano, Giuseppe

2016-01-01

A wide range of lactic acid bacteria (LAB) is able to produce capsular or extracellular polysaccharides, with various chemical compositions and properties. Polysaccharides produced by LAB alter the rheological properties of the matrix in which they are dispersed, leading to typically viscous and
Retinoic acid modulation of ultraviolet light-induced epidermal ornithine decarboxylase activity

International Nuclear Information System (INIS)

Lowe, N.J.; Breeding, J.

1982-01-01

Irradiation of skin with ultraviolet light of sunburn range (UVB) leads to a large and rapid induction of the polyamine biosynthetic enzyme ornithine decarboxylase in the epidermis. Induction of epidermal ornithine decarboxylase also occurs following application of the tumor promoting agent 12-0-tetradecanoylphorbol-13 acetate and topical retinoic acid is able to block both this ornithine decarboxylase induction and skin tumor promotion. In the studies described below, topical application of retinoic acid to hairless mouse skin leads to a significant inhibition of UVB-induced epidermal ornithine decarboxylase activity. The degree of this inhibition was dependent on the dose, timing, and frequency of the application of retinoic acid. To show significant inhibition of UVB-induced ornithine decarboxylase the retinoic acid had to be applied within 5 hr of UVB irradiation. If retinoic acid treatment was delayed beyond 7 hr following UVB, then no inhibition of UVB-induced ornithine decarboxylase was observed. The quantities of retinoic acid used (1.7 nmol and 3.4 nmol) have been shown effective at inhibiting 12-0-tetradecanoyl phorbol-13 acetate induced ornithine decarboxylase. The results show that these concentrations of topical retinoic acid applied either before or immediately following UVB irradiation reduces the UVB induction of epidermal ornithine decarboxylase. The effect of retinoic acid in these regimens on UVB-induced skin carcinogenesis is currently under study
Acidic leaching of potentially toxic metals cadmium, cobalt, chromium, copper, nickel, lead, and zinc from two Zn smelting slag materials incubated in an acidic soil.

Science.gov (United States)

Liu, Taoze; Li, Feili; Jin, Zhisheng; Yang, Yuangen

2018-07-01

A column leaching study, coupled with acid deposition simulation, was conducted to investigate the leaching of potentially toxic metals (PTM) from zinc smelting slag materials (SSM) after being incubated in an acid Alfisol for 120 days at room temperature. Two SSMs (SSM-A: acidic, 10 yrs exposure with moderate high PTM concentrations versus SSM-B: alkaline, 2 yrs exposure with extremely high PTM concentrations), were used for the incubation at 0.5, 1, 2.5, 5 wt% amendment ratios in triplicate. Five leaching events were conducted at day 1, 3, 7, 14, and 28, and the leaching of PTMs mainly occurred in the first three leaching events, with the highest PTM concentrations in leachate measured from 5 wt% SSM amendments. After leaching, 2.5, 12, 5.5, 14, 11, and 9 wt% of M3 extractable Pb, Zn, Cd, Co, Cr, and Ni could be released from 5 wt% SSM-A amended soils, being respectively 25, 12, 4, 2, 2, and 2 times more than those from 5 wt% SSM-B amended soils. In the leachates, the concentrations of PTMs were mostly affected by leachant pH and were closely correlated to the concentrations of Fe, Al, Ca, Mg and P with Cd, Pb, and Zn showing the most environmental concern. Visual MINTEQ 3.1 modeling suggested metallic ions and sulfate forms as the common chemical species of PTMs in the leachates; whereas, organic bound species showed importance for Cd, Pb, Cu, and Ni, and CdCl + was observed for Cd. Aluminum hydroxy, phosphate, and sulfate minerals prevailed as the saturated minerals, followed by chloropyromorphite (Pb 5 (PO 4 ) 3 Cl) and plumbogummite (PbAl 3 (PO 4 ) 2 (OH) 5 ·H 2 O) in the leachates. This study suggested that incubation of SSMs in acidic soil for a long term can enhance the release of PTMs as the forms of metallic ions and sulfate when subjected to acid deposition leaching. Copyright © 2018 Elsevier Ltd. All rights reserved.

Heavy metals, especially lead, deposition recorded in an ombrotrophic peat bog near Manchester, United Kingdom

Science.gov (United States)

Le Roux, G.; Weiss, D.; Cheburkin, A.; Rausch, N.; Grattant, J.; Krachler, M.; Shotyk, W.

2003-05-01

A peat monolith representing up to 4,000 years of peat accumulation near Manchester, England, was collected. Major and trace elements were analysed with XRF and for Cd and Pb in the deeper samples with GF-AAS following acid digestion. Pb isotopic composition was measured with TIMS and ICP-MS. The results show a pollution since the Roman Period due to local lead sources and an increase in lead pollution in the last century due to leaded gasoline as fingerprinted by Pb isotopic signatures.
Chronic lead intoxication; Chronische Bleiintoxikation

Energy Technology Data Exchange (ETDEWEB)

Wieseler, B.; Leng, G. [Duesseldorf Univ. (Germany). Inst. fuer Hygiene; Lenz, S.; Schultz, C. [Klinikum Remscheid GmbH, Remscheid (Germany); Wilhelm, M. [Bochum Univ. (Germany). Inst. fuer Hygiene, Sozial- und Umweltmedizin

1999-02-01

The case of a female 68 years old patient is described. Here, a chronic lead intoxication was diagnosed after a two year old medical history with increasing attacks of colic-like abdominal pain often described as life-threatening. After repeated hospitalizations and intensive search for the cause of the symptoms, porphyria and anemia was found to be a sign of a chronic lead poisoning. The blood lead concentrations were always about a level of 600 {mu}g/L. The source of exposure could not be found by now. Neither home inspection nor environmental investigations have shown a recent source of lead intake by the patient. However, a possible occupational source of lead exposure at a blast furnace was established by anamnesis for 1952 to 1962. Thus, osteoporosis induced lead mobilisation was suspected. Noticeable are the results of the six abdominal survey radiographies taken during hospitalization within one year; three radiographies were taken following clinical admission and three before discharge of the patient. In comparison, the course shows a chronic relapsing alimentary supply from metallic particles of unknown genesis. The patient was treated with the sodium salt of 2,3-dimercapto-1-propansulfonic acid (DMPS, Dimaval{sup TM}). She was free of complain afterwards. Following therapy, the blood lead concentrations fell under a level of 400 {mu}m/L, but after several weeks the lead level raised up to the original level of 600 {mu}g/L. (orig.) [Deutsch] Es wird eine 68jaehrige Patientin vorgestellt, bei der nach fast zweijaehriger Krankengeschichte, die gekennzeichnet war durch rezidivierende, teils als lebensbedrohlich geschilderte Bauchkoliken, eine chronische Bleiintoxikation diagnostiziert wurde. Erst nach wiederholten stationaeren Krankenhausaufenthalten mit intensiver Suche nach der Krankheitsursache wurden das Krankheitsbild und die Laborwerte durch Zusatzuntersuchungen ergaenzt, so dass sich in der festgestellten Porphyrie und Anaemie die Diagnose der
A fast atom bombardment study of the lead isotope ratios in early nineteenth century Niagara Peninsula pottery glazes

International Nuclear Information System (INIS)

Miller, J.M.; Jones, T.R.B.; Kenney, Tina; Rupp, D.W.

1986-01-01

The application of fast atom bombardment (FAB) mass spectrometry to the determination of lead isotope ratios in nineteenth century pottery glazes from the Niagara Peninsula has been investigated with the aim of determining the source of the lead used in the glazes. Methods of sampling have been compared, including direct analysis of glass chips, analysis of powdered glaze scrapings, analysis of acid extracts of the former, and simple acid leaching of the surface of a piece of pottery. The latter method gave the best results. The FAB data, as obtained on an older mass spectrometer, can distinguish lead from igneous vs. sedimentary deposits, but is not adequate to determine specific mining locations. Although newer FAB instrumentation can narrow this range, the overlap of data from the Niagara Peninsula and England precludes a simple answer to the archeological question as to English vs. Canadian origin of the lead used in the Jordan pottery glazes. However, the data do suggest that the potter used a local source for the lead
Lead optimization of a pyridine-carboxamide series as DGAT-1 inhibitors.

Science.gov (United States)

Ting, Pauline C; Lee, Joe F; Zorn, Nicolas; Kim, Hyunjin M; Aslanian, Robert G; Lin, Mingxiang; Smith, Michelle; Walker, Scott S; Cook, John; Van Heek, Margaret; Lachowicz, Jean

2013-02-15

The structure-activity relationship studies of a novel series of carboxylic acid derivatives of pyridine-carboxamides as DGAT-1 inhibitors is described. The optimization of the initial lead compound 6 based on in vitro and in vivo activity led to the discovery of key compounds 10j and 17h. Copyright © 2013 Elsevier Ltd. All rights reserved.
Metabolic engineering of lactic acid bacteria for the production of nutraceuticals

NARCIS (Netherlands)

Hugenholtz, J.; Sybesma, W.; Groot, M.N.; Wisselink, W.; Ladero, V.; Burgess, K.; Sinderen, van D.; Piard, J.C.; Eggink, G.; Smid, E.J.; Savoy, G.; Sesma, F.; Jansen, T.; Hols, P.; Kleerebezem, M.

2002-01-01

Lactic acid bacteria display a relatively simple and well-described metabolism where the sugar source is converted mainly to lactic acid. Here we will shortly describe metabolic engineering strategies on the level of sugar metabolism, that lead to either the efficient re-routing of the lactococcal
Detection of coronary artery disease using 12-lead electrocardiogram and simultaneous dual myocardial imaging with iodine-123-β-methyl iodophenyl-pentadecanoic acid (BMIPP) and thallium-201 in patients with unstable angina

International Nuclear Information System (INIS)

Saitoh, Makoto; Hasegawa, Koh; Hasegawa, Kazuo; Kondoh, Teruo; Yanagawa, Tetsuo.

1995-01-01

We investigated the usefulness of 12-lead electrocardiogram and simultaneous single-photon emission computed tomography (SPECT) with 123 I-β-methyl iodophenyl-pentadecanoic acid (BMIPP) and thallium-201 ( 201 Tl) for detecting coronary artery disease (CAD) in 54 consecutive patients with unstable angina. Discordant BMIPP uptake was defined as less 123 I-BMIPP uptake than 201 Tl uptake in 123 I-BMIPP/ 201 Tl dual SPECT. In the detection of CAD, ischemic electrocardiographic change during anginal attack had high sensitivity and low specificity, while discordant BMIPP finding had low sensitivity and high specificity. In patients showing ST depression during anginal attack, discordant BMIPP uptake showed high sensitivity and high specificity for detecting CAD. In conclusion, both 12-lead electrocardiogram during anginal attack and discordant BMIPP uptake are useful in detecting CAD in patients with unstable angina. (author)
Lead and zinc contamination of vegetation in the southern Pennines

Energy Technology Data Exchange (ETDEWEB)

Shimwell, D W; Laurie, A E

1972-01-01

Three types of heavy metal tolerant vegetation occurring on the spoil heaps in the Pennines are described sociologically and ecologically and their distribution in the Peak District National Park mapped. Concentrations of lead and zinc extractable from soils by acetic acid are recorded, as are total values for these two heavy metals in the tissues of the main component phanerogams and cryptogams of the vegetation. The range of values for zinc in plant tissues are uniformly higher than those for lead. Concentrations of lead accumulated by these plants are higher than those reported for the accumulation of atmospheric lead. The differences in heavy metal absorption, retention and excretion between ectohydric and myxohydric mosses are shown to be quite distinct. The heavy metals are excreted in the former type and form a crust in periods of drought with up to 6% lead and 1.5% zinc content, while, in the latter, the metals tend to be located mainly in the older growth at the base of the moss carpets. The concentrations of the two metal ions in two Peak District rivers proved to be less than 1 ppm in all samples.
Total contribution of airborne lead to blood lead.

OpenAIRE

Manton, W I

1985-01-01

A nine year study of blood lead concentrations and isotope ratios carried out on a married couple shows that pulmonary deposition cannot account for all the airborne lead in blood; that lead from bone may comprise 70% of blood lead; and that during pregnancy blood lead may double due to mobilisation of lead from bone.
n-3 fatty acids reduce plasma 20-hydroxyeicosatetraenoic acid and blood pressure in patients with chronic kidney disease.

Science.gov (United States)

Barden, Anne E; Burke, Valerie; Mas, Emilie; Beilin, Lawrence J; Puddey, Ian B; Watts, Gerald F; Irish, Ashley B; Mori, Trevor A

2015-09-01

Metabolism of arachidonic acid by cytochrome P450 ω-hydroxylase leads to the formation of 20-hydroxyeicosatetraenoic acid (20-HETE) that regulates vascular function, sodium homeostasis and blood pressure (BP). Supplementation with n-3 fatty acids is known to alter arachidonic acid metabolism and reduce the formation of the lipid peroxidation products F2-isoprostanes, but the effect of n-3 fatty acids on 20-HETE has not been studied. We previously reported a significant effect of n-3 fatty acids but not coenzyme Q10 (CoQ) to reduce BP in a double-blind, placebo-controlled intervention, wherein patients with chronic kidney disease (CKD) were randomized to n-3 fatty acids (4 g), CoQ (200 mg), both supplements or control (4 g olive oil), daily for 8 weeks. This study examined the effect of n-3 fatty acids on plasma and urinary 20-HETE in the same study, as well as plasma and urinary F2-isoprostanes, and relate these to changes in BP. Seventy-four patients completed the 8-week intervention. n-3 fatty acids but not CoQ significantly reduced plasma 20-HETE (P = 0.001) and F2-isoprostanes (P fatty acids. This is the first report that n-3 fatty acid supplementation reduces plasma 20-HETE in humans and that this associates with reduced BP. These results provide a plausible mechanism for the reduction in BP observed in patients with CKD following n-3 fatty acid supplementation.
Effect of aluminum, zinc, copper, and lead on the acid-base properties of water extracts from soils

Science.gov (United States)

Motuzova, G. V.; Makarychev, I. P.; Petrov, M. I.

2013-01-01

The potentiometric titration of water extracts from the upper horizons of taiga-zone soils by salt solutions of heavy metals (Pb, Cu, and Zn) showed that their addition is an additional source of the extract acidity because of the involvement of the metal ions in complexation with water-soluble organic substances (WSOSs). At the addition of 0.01 M water solutions of Al(NO3)3 to water extracts from soils, Al3+ ions are also involved in complexes with WSOSs, which is accompanied by stronger acidification of the extracts from the upper horizon of soddy soils (with a near-neutral reaction) than from the litter of bog-podzolic soil (with a strongly acid reaction). The effect of the Al3+ hydrolysis on the acidity of the extracts is insignificantly low in both cases. A quantitative relationship was revealed between the release of protons and the ratio of free Cu2+ ions to those complexed with WSOSs at the titration of water extracts from soils by a solution of copper salt.
Investigation of the leaching behavior of lead in stabilized/solidified waste using a two-year semi-dynamic leaching test.

Science.gov (United States)

Xue, Qiang; Wang, Ping; Li, Jiang-Shan; Zhang, Ting-Ting; Wang, Shan-Yong

2017-01-01

Long-term leaching behavior of contaminant from stabilization/solidification (S/S) treated waste stays unclear. For the purpose of studying long-term leaching behavior and leaching mechanism of lead from cement stabilized soil under different pH environment, semi-dynamic leaching test was extended to two years to investigate leaching behaviors of S/S treated lead contaminated soil. Effectiveness of S/S treatment in different scenarios was evaluated by leachability index (LX) and effective diffusion coefficient (D e ). In addition, the long-term leaching mechanism was investigated at different leaching periods. Results showed that no significant difference was observed among the values of the cumulative release of Pb, D e and LX in weakly alkaline and weakly acidic environment (pH value varied from 5.00 to 10.00), and all the controlling leaching mechanisms of the samples immersed in weakly alkaline and weakly acidic environments turned out to be diffusion. Strong acid environment would significantly affect the leaching behavior and leaching mechanism of lead from S/S monolith. The two-year variation of D e appeared to be time dependent, and D e values increased after the 210 th day in weakly alkaline and weakly acidic environment. Copyright © 2016 Elsevier Ltd. All rights reserved.
Comparative study of trichloroacetic acid vs. photodynamic therapy with topical 5-aminolevulinic acid for actinic keratosis of the scalp.

Science.gov (United States)

Di Nuzzo, Sergio; Cortelazzi, Chiara; Boccaletti, Valeria; Zucchi, Alfredo; Conti, Maria Luisa; Montanari, Paola; Feliciani, Claudio; Fabrizi, Giuseppe; Pagliarello, Calogero

2015-09-01

Photodynamic therapy with 5-methyl-aminolevulinate and photodynamic therapy with trichloroacetic acid 50% are the two techniques utilized in the management of actinic keratosis. This study was planned to compare the efficacy, adverse effects, recurrence and cosmetic outcome of these option therapies in patients with multiple actinic keratosis of the scalp. Thirteen patients with multiple actinic keratosis were treated with one of the two treatments on half of the scalp at baseline, while the other treatment was performed on the other half 15 days apart, randomly. Efficacy, adverse effects, cosmetic outcome and recurrence were recorded at follow-up visit at 1, 3, 6 and 12 months. Photodynamic therapy with 5 methyl-aminolevulinate was more effective than trichloroacetic acid although less tolerated by patients as it was more painful. Early adverse effects were almost the same even if trichloroacetic acid leads also to crust formation and to a worse cosmetic outcome characterized by hypopigmentation. Recurrence was lower in the area treated with photodynamic therapy. Trichloroacetic acid 50% is less effective than photodynamic therapy with 5 methyl-aminolevulinate in the treatment of multiple actinic keratosis of the scalp although better tolerated by patients. As this technique is less painful and less expensive than photodynamic therapy, we hypothesize and suggest that more sequential treatments could lead to better results. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Total contribution of airborne lead to blood lead.

Science.gov (United States)

Manton, W I

1985-01-01

A nine year study of blood lead concentrations and isotope ratios carried out on a married couple shows that pulmonary deposition cannot account for all the airborne lead in blood; that lead from bone may comprise 70% of blood lead; and that during pregnancy blood lead may double due to mobilisation of lead from bone. PMID:3970881
Snapping turtles (Chelydra serpentina) as biomonitors of lead contamination of the Big River in Missouri`s Old Lead Belt

Energy Technology Data Exchange (ETDEWEB)

Overmann, S.R.; Krajicek, J.J. [Southeast Missouri State Univ., Cape Girardeau, MO (United States). Dept. of Biology

1995-04-01

The usefulness of common snapping turtles (Chelydra serpentina) as biomonitors of lead (Pb) contamination of aquatic ecosystems was assessed. Thirty-seven snapping turtles were collected from three sites on the Big River, an Ozarkian stream contaminated with Pb mine tailings. Morphometric measurements, tissue Pb concentrations (muscle, blood, bone, carapace, brain, and liver), {delta}-aminolevulinic acid dehydratase ({delta}-ALAD) activity, hematocrit, hemoglobin, plasma glucose, osmolality, and chloride ion content were measured. The data showed no effects of Pb contamination on capture success or morphological measurements. Tissue Pb concentrations were related to capture location. Hematocrit, plasma osmolality, plasma glucose, and plasma chloride ion content were not significantly different with respect to capture location. The {delta}-ALAD activity levels were decreased in turtles taken from contaminated sites. Lead levels in the Big River do not appear to be adversely affecting the snapping turtles of the river. Chelydra serpentina is a useful species for biomonitoring of Pb-contaminated aquatic environments.
Lead- or Lead-bismuth-cooled fast reactors

International Nuclear Information System (INIS)

Bouchter, J.C.; Courouau, J.L.; Dufour, P.; Guidez, J.; Latge, C.; Martinelli, L.; Renault, C.; Rimpault, G.

2014-01-01

Lead-cooled fast reactors are one of the 6 concepts retained for the 4. generation of nuclear reactors. So far no lead-cooled reactors have existed in the world except lead-bismuth-cooled reactors in soviet submarines. Some problems linked to the use of the lead-bismuth eutectic appeared but were satisfactorily solved by a more rigorous monitoring of the chemistry of the lead-bismuth coolant. Lead presents various advantages as a coolant: no reactivity with water and the air,a high boiling temperature and low contamination when irradiated. The main asset of the lead-bismuth alloy is the drop of the fusion temperature from 327 C degrees to 125 C degrees. The main drawback of using lead (or lead-bismuth) is its high corrosiveness with metals like iron, chromium and nickel. The high corrosiveness of the coolant implies low flow velocities which means a bigger core and consequently a bigger reactor containment. Different research programs in the world (in Europe, Russia and the USA) are reviewed in the article but it appears that the development of this type of reactor requires technological breakthroughs concerning materials and the resistance to corrosion. Furthermore the concept of lead-cooled reactors seems to be associated to a range of low output power because of the compromise between the size of the reactor and its resistance to earthquakes. (A.C.)
Okadaic Acid, a Bioactive Fatty Acid from Halichondria okadai, Stimulates Lipolysis in Rat Adipocytes: The Pivotal Role of Perilipin Translocation

Directory of Open Access Journals (Sweden)

Nen-Chung Chang

2013-01-01

Full Text Available Lipid metabolism in visceral fat cells is correlated with metabolic syndrome and cardiovascular diseases. Okadaic-acid, a 38-carbon fatty acid isolated from the black sponge Halichondria okadai, can stimulate lipolysis by promoting the phosphorylation of several proteins in adipocytes. However, the mechanism of okadaic acid-induced lipolysis and the effects of okadaic acid on lipid-droplet-associated proteins (perilipins and beta-actin remain unclear. We isolated adipocytes from rat epididymal fat pads and treated them with isoproterenol and/or okadaic acid to estimate lipolysis by measuring glycerol release. Incubating adipocytes with okadaic acid stimulated time-dependent lipolysis. Lipid-droplet-associated perilipins and beta-actin were analyzed by immunoblotting and immunofluorescence, and the association of perilipin A and B was found to be decreased in response to isoproterenol or okadaic acid treatment. Moreover, okadaic-acid treatment could enhance isoproterenol-mediated lipolysis, whereas treatment of several inhibitors such as KT-5720 (PKA inhibitor, calphostin C (PKC inhibitor, or KT-5823 (PKG inhibitor did not attenuate okadaic-acid-induced lipolysis. By contrast, vanadyl acetylacetonate (tyrosine phosphatase inhibitor blocked okadaic-acid-dependent lipolysis. These results suggest that okadaic acid induces the phosphorylation and detachment of lipid-droplet-associated perilipin A and B from the lipid droplet surface and thereby leads to accelerated lipolysis.
Lead in teeth from lead-dosed goats: Microdistribution and relationship to the cumulative lead dose

International Nuclear Information System (INIS)

Bellis, David J.; Hetter, Katherine M.; Jones, Joseph; Amarasiriwardena, Dula; Parsons, Patrick J.

2008-01-01

Teeth are commonly used as a biomarker of long-term lead exposure. There appear to be few data, however, on the content or distribution of lead in teeth where data on specific lead intake (dose) are also available. This study describes the analysis of a convenience sample of teeth from animals that were dosed with lead for other purposes, i.e., a proficiency testing program for blood lead. Lead concentration of whole teeth obtained from 23 animals, as determined by atomic absorption spectrometry, varied from 0.6 to 80 μg g -1 . Linear regression of whole tooth lead (μg g -1 ) on the cumulative lead dose received by the animal (g) yielded a slope of 1.2, with r 2 =0.647 (p -1 , were found in circumpulpal dentine. Linear regression of circumpulpal lead (μg g -1 ) on cumulative lead dose (g) yielded a slope of 23 with r 2 =0.961 (p=0.0001). The data indicated that whole tooth lead, and especially circumpulpal lead, of dosed goats increased linearly with cumulative lead exposure. These data suggest that circumpulpal dentine is a better biomarker of cumulative lead exposure than is whole tooth lead, at least for lead-dosed goats
Molasses melanoidin-like products enhance phytoextraction of lead through three Brassica species.

Science.gov (United States)

Hatano, Ken-Ichi; Yamatsu, Takeshi

2018-05-12

Previously, it has been suggested that melanoidin-like products (MLP) from sugarcane molasses may accelerate copper phytoextraction. In this study, we evaluated the facilitatory effect of MLP on phytoextraction in a medium including cadmium or lead, the concentrations of which were adjusted around the regulation values of the Soil Contamination Countermeasures Act in Japan. Three Brassica species were tested based on their fast growth, high biomass productivity, and high heavy metal absorption. Both biomass and lead uptake in the nutrient medium with 1 mM lead nitrate were significantly increased by the addition of MLP, and almost all of the lead was accumulated in the root tissue. Therefore, MLP were able both to detoxify lead ions and to improve their bioavailability in Brassica species. In contrast, only these species with MLP or citric acid survived in the nutrient medium with 1 mM cadmium sulfate. The phytoextraction of cadmium using these species was therefore impractical under the Act.
Morphology of enamel in primary teeth from children in Thailand exposed to environmental lead

International Nuclear Information System (INIS)

Youravong, Nattaporn; Chongsuvivatwong, Virasakdi; Teanpaisan, Rawee; Geater, Alan F.; Dietz, Wolfram; Dahlen, Gunnar; Noren, Joergen G.

2005-01-01

Lead is one of the major environmental pollutants and a health risk. Dental hard tissues have a capacity to accumulate lead from the environment. Eighty exfoliated primary teeth were collected from children residing around a shipyard area in southern Thailand, known for its lead contamination. The morphology of the enamel was examined by polarized light microscopy (PLM), microradiography (MRG), and scanning electron microscopy (SEM). The specimens derived from two groups of children, one group with high blood levels of lead (57 teeth) and one group having low blood levels of lead (23 teeth). The enamel irrespective of group appeared normal. However, in a majority of the specimens the enamel surface appeared hypomineralized, which was confirmed in SEM. No morphological changes connected to lead in blood could be found. The hypomineralized surface zone could possibly be attributed to an acid oral environment
Morphology of enamel in primary teeth from children in Thailand exposed to environmental lead

Energy Technology Data Exchange (ETDEWEB)

Youravong, Nattaporn [Epidemiology Unit, Faculty of Medicine, Prince of Songkla University, Songkhla (Thailand); Chongsuvivatwong, Virasakdi [Epidemiology Unit, Faculty of Medicine, Prince of Songkla University, Songkhla (Thailand); Teanpaisan, Rawee [Department of Stomatology, Faculty of Dentistry, Prince of Songkla University, Songkhla (Thailand); Geater, Alan F. [Epidemiology Unit, Faculty of Medicine, Prince of Songkla University, Songkhla (Thailand); Dietz, Wolfram [Centre of Electron Microscopy, Friedrich-Schiller-University Jena (Germany); Dahlen, Gunnar [Department of Oral Microbiology, Faculty of Odontology, Goeteborg University (Sweden); Noren, Joergen G. [Department of Pedodontics, Faculty of Odontology, Goeteborg University, Box 450 SE-405 30 Goeteborg (Sweden)]. E-mail: Jorgen.noren@odontologi.gu.se

2005-09-15

Lead is one of the major environmental pollutants and a health risk. Dental hard tissues have a capacity to accumulate lead from the environment. Eighty exfoliated primary teeth were collected from children residing around a shipyard area in southern Thailand, known for its lead contamination. The morphology of the enamel was examined by polarized light microscopy (PLM), microradiography (MRG), and scanning electron microscopy (SEM). The specimens derived from two groups of children, one group with high blood levels of lead (57 teeth) and one group having low blood levels of lead (23 teeth). The enamel irrespective of group appeared normal. However, in a majority of the specimens the enamel surface appeared hypomineralized, which was confirmed in SEM. No morphological changes connected to lead in blood could be found. The hypomineralized surface zone could possibly be attributed to an acid oral environment.

Some links on this page may take you to non-federal websites. Their policies may differ from this site.