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Sample records for advanced lead acid

  1. Utilization of a bipolar lead acid battery for the advanced launch system

    NASA Technical Reports Server (NTRS)

    Gentry, William O.; Vidas, Robin; Miles, Ronald; Eckles, Steven

    1991-01-01

    The development of a battery comprised of bipolar lead acid modules is discussed. The battery is designed to satisfy the requirements of the Advanced Launch System (ALS). The battery will have the following design features: (1) conventional lead acid chemistry; (2) thin electrode/active materials; (3) a thin separator; (4) sealed construction (gas recombinant); and (5) welded plastic frames for the external seal.

  2. Application features and considerations in advanced lead-acid and nickel/iron EV batteries

    SciTech Connect

    Miller, J.F.; Rajan, J.B.; Lee, T.S.; Christianson, C.C.; Hornstra, F.; Yao, N.P.

    1983-01-01

    In the development of advanced lead-acid and nickel/iron EV batteries, major efforts have focussed on improving specific energy, specific power, cycle life, and cost. Nonetheless, other battery characteristics related to application needs are also important features which must be considered during the battery development process. This paper describes various application features and improvements incorporated in these advanced lead-acid and nickel/iron EV batteries. Their volumetric energy density and packaging flexibility are presented: their charged-stand capabilities and energy efficiencies are reported; and development work on the safe control of battery off-gases and the implementation of single-point watering systems is discussed.

  3. Carbon honeycomb grids for advanced lead-acid batteries. Part I: Proof of concept

    NASA Astrophysics Data System (ADS)

    Kirchev, Angel; Kircheva, Nina; Perrin, Marion

    2011-10-01

    The carbon honeycomb grid is proposed as innovative solution for high energy density lead acid battery. The proof of concept is demonstrated, developing grids suitable for the small capacity, scale of valve-regulated lead acid batteries with 2.5-3 Ah plates. The manufacturing of the grids, includes fast, known and simple processes which can be rescaled for mass production with a minimum, investment costs. The most critical process of green composite carbonisation by heating in inert, atmosphere from 200 to 1000 °C takes about 5 h, guaranteeing the low cost of the grids. An AGM-VRLA, cell with prototype positive plate based on the lead-2% tin electroplated carbon honeycomb grid and, conventional negative plates is cycled demonstrating 191 deep cycles. The impedance spectroscopy, measurements indicate the grid performance remains acceptable despite the evolution of the corrosion, processes during the cycling.

  4. Carbon honeycomb grids for advanced lead-acid batteries. Part III: Technology scale-up

    NASA Astrophysics Data System (ADS)

    Kirchev, A.; Serra, L.; Dumenil, S.; Brichard, G.; Alias, M.; Jammet, B.; Vinit, L.

    2015-12-01

    The carbon honeycomb grid technology employs new carbon/carbon composites with ordered 3D structure instead of the classic lead-acid battery current collectors. The technology is laboratory scaled up from small size grids corresponding to electrodes with a capacity of 3 Ah to current collectors suitable for assembly of lead-acid batteries covering the majority of the typical lead-acid battery applications. Two series of 150 grids each (one positive and one negative) are manufactured using low-cost lab-scale equipment. They are further subjected to pasting with active materials and the resulting battery plates are assembled in 12 V AGM-VLRA battery mono-blocks for laboratory testing and outdoor demonstration in electric scooter replacing its original VRLAB pack. The obtained results demonstrate that the technology can replace successfully the state of the art negative grids with considerable benefits. The use of the carbon honeycomb grids as positive plate current collectors is limited by the anodic corrosion of the entire structure attacking both the carbon/carbon composite part and the electroplated lead-tin alloy coating.

  5. Carbon honeycomb grids for advanced lead-acid batteries. Part II: Operation of the negative plates

    NASA Astrophysics Data System (ADS)

    Kirchev, A.; Dumenil, S.; Alias, M.; Christin, R.; de Mascarel, A.; Perrin, M.

    2015-04-01

    The article presents the recent progress in the carbon honeycomb grid technology for valve-regulated lead-acid batteries with absorptive glass-mat separators (AGM-VRLAB). The work is focused on the development of negative current collectors using industrial grade composite honeycomb precursors. The developed model AGM-VRLA cells comprised of one prototype honeycomb negative electrode and two conventional traction positive counter-electrodes show high utilisation of the negative active material and long cycle life both in high-rate partial state of charge (HRPSoC) cycling mode and in deep cycling mode. The analysis of the results from the cycle-life tests and the tear-down analysis indicate that the benefits delivered by the novel grids can be related to the low mesh size of the grid, low γ-coefficient, as well as the use of milled carbon fibre additive. The combination of the three, results in the reversibility of the negative active material sulfation process when the electrolyte concentration in the cells is lower than the one traditionally used in the AGM-VRLAB technology. The negative plates show no signs of irreversible degradation after more than 900 cycles in deep cycling mode and more than 2000 capacity turnovers (equivalent cycles) in HRPSoC cycling mode.

  6. Lead/acid batteries

    NASA Astrophysics Data System (ADS)

    Bullock, Kathryn R.

    Lead/acid batteries are produced in sizes from less than 1 to 3000 Ah for a wide variety of portable, industrial and automotive applications. Designs include Planté, Fauré or pasted, and tubular electrodes. In addition to the traditional designs which are flooded with sulfuric acid, newer 'valve-regulated" designs have the acid immolibized in a silica gel or absorbed in a porous glass separator. Development is ongoing worldwide to increase the specific power, energy and deep discharge cycle life of this commercially successful system to meet the needs of new applications such as electric vehicles, load leveling, and solar energy storage. The operating principles, current status, technical challenges and commercial impact of the lead/acid battery are reviewed.

  7. Assessment of high power HEV lead-acid battery advancements by comparative benchmarking with a European test procedure

    NASA Astrophysics Data System (ADS)

    Conte, Mario; Pede, Giovanni; Sglavo, Vincenzo; Macerata, Diego

    The technical and practical suitability of lead-acid batteries for applications in vehicles with electrical drivetrains (battery-powered or hybrid electric) has been experimentally investigated in a variety of testing programmes. Under the direction and funding support of the Commission of the European Community, since early 1990s, the R&D Organisation EUCAR, a collaborative partnership of most European car manufacturers, has been conducting battery technological assessment projects, through bench tests carried out by different independent laboratories throughout Europe, using agreed test procedures. In this framework, ENEA acted as independent testing institute and tested, among others, three high power lead-acid batteries of various technologies (flat plate electrodes and spiral wound) for EV and HEV applications. In addition, different battery sizes and operating conditions have been tested at ENEA in a separate collaboration with ALTRA-IRISBUS. This paper intends to trace technological and performance improvements of high power lead-acid battery technology through the analysis of experimental data during parameter and life cycle tests, including the effects of battery sizes, charge/discharge profiles and testing procedures, with special emphasis on the reduction of the internal resistance and the variation of peak power and cycle life.

  8. Lead-acid battery

    NASA Technical Reports Server (NTRS)

    Rowlette, John J. (Inventor)

    1983-01-01

    A light weight lead-acid battery (30) having a positive terminal (36) and a negative terminal (34) and including one or more cells or grid stacks having a plurality of vertically stacked conductive monoplates (10, 20) with positive active material and negative active material deposited on alternating plates in the cell or grid stack. Electrolyte layers (26, 28) positioned between each monoplate are included to provide a battery cell having four sides which is capable of being electrically charged and discharged. Two vertical positive bus bars (42, 43) are provided on opposite sides of the battery cell for connecting the monoplates (10) with positive active material together in parallel current conducting relation. In addition, two negative bus bars (38, 39) on opposite sides of the battery cell each being adjacent the positive bus bars are provided for connecting the monoplates (20) with negative active material together in parallel current conducting relation. The positive (42, 43) and negative (38, 39) bus bars not only provide a low resistance method for connecting the plurality of conductive monoplates of their respective battery terminals (36, 34) but also provides support and structural strength to the battery cell structure. In addition, horizontal orientation of monoplates (10, 20) is provided in a vertical stacking arrangement to reduce electrolyte stratification and short circuiting due to flaking of positive and negative active materials from the monoplates.

  9. Lead-acid and lithium-ion batteries for the Chinese electric bike market and implications on future technology advancement

    NASA Astrophysics Data System (ADS)

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

    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.

  10. Rigid separator lead acid batteries

    SciTech Connect

    Cannone, A.G.; Salkind, A.J.; Stempin, J.L.; Wexell, D.R.

    1996-11-01

    Lead acid cells assembled with extruded separators displayed relatively uniform capacity and voltage parameters through 100{sup +} cycles of charge/discharge. This contrasts to failure of control cells with glass mat separators after 60 cycles. The mullite/alumina separators with 50, 60, and 70% porosity separators appear suitable for both flooded and sealed lead acid cell applications. The advantages of the rigid ceramic separators over fiber mat materials are in the uniformity of capacity and voltage, the ease of cell assembly, and the probability that firm stacking pressure on the active material will yield greater cycle life, especially at elevated temperatures.

  11. High power bipolar lead-acid batteries

    NASA Technical Reports Server (NTRS)

    Halpert, Gerald; Attia, Alan

    1991-01-01

    The Jet Propulsion Laboratory (JPL), with interest in advanced energy storage systems, is involved in the development of a unique lead acid battery design. This battery utilizes the same combination of lead and lead dioxide active materials present in the automobile starting battery. However, it can provide 2 to 10 times the power while minimizing volume and weight. The typical starting battery is described as a monopolar type using one current collector for both the positive and negative plate of adjacent cells. Specific power as high as 2.5 kW/kg was projected for 30 second periods with as many as 2000 recharge cycles.

  12. Lead-acid battery construction

    NASA Technical Reports Server (NTRS)

    Rowlette, John J. (Inventor)

    1988-01-01

    The power characteristics of a lead-acid battery are improved by incorporating a dispersion of 1 to 10% by weight of a thermodynamically stable conductivity additive, such as conductive tin oxide coated glass fibers (34) of filamentary glass wool (42) in the positive active layer (32) carried on the grid (30) of the positive plate (16). The avoiding of positive plate reversal to prevent reduction of the tin oxide is accomplished by (a) employing an oversized positive plate and pre-charging it; (b) by pre-discharging the negative plate; and/or (c) by placing a circuit breaker (26) in combination with the plates (16, 18) and terminals (22, 24) to remove the load when the voltage of the positive plate falls below a pre-selected level.

  13. Determination of the lead-acid battery's dynamic response using Butler-Volmer equation for advanced battery management systems in automotive applications

    NASA Astrophysics Data System (ADS)

    Piłatowicz, Grzegorz; Budde-Meiwes, Heide; Kowal, Julia; Sarfert, Christel; Schoch, Eberhard; Königsmann, Martin; Sauer, Dirk Uwe

    2016-11-01

    Micro-hybrid vehicles (μH) are currently starting to dominate the European market and seize constantly growing share of other leading markets in the world. On the one hand, the additional functionality of μH reduces the CO2 emissions and improves the fuel economy, but, on the other hand, the additional stress imposed on the lead-acid battery reduces significantly its expected service life in comparison to conventional vehicles. Because of that μH require highly accurate battery state detection solutions. They are necessary to ensure the vehicle reliability requirements, prolong service life and reduce warranty costs. This paper presents an electrical model based on Butler-Volmer equation. The main novelty of the presented approach is its ability to predict accurately dynamic response of a battery considering a wide range of discharge current rates, state-of-charges and temperatures. Presented approach is fully implementable and adaptable in state-of-the-art low-cost platforms. Additionally, shown results indicate that it is applicable as a supporting tool for state-of-charge and state-of-health estimation and scalable for the different battery technologies and sizes. Validation using both static pulses and dynamic driving profile resulted in average absolute error of 124 mV regarding cranking current rate of 800 A respectively.

  14. Lead exposure among lead-acid battery workers in Jamaica.

    PubMed

    Matte, T D; Figueroa, J P; Burr, G; Flesch, J P; Keenlyside, R A; Baker, E L

    1989-01-01

    To assess lead exposure in the Jamaican lead-acid battery industry, we surveyed three battery manufacturers (including 46 production workers) and 10 battery repair shops (including 23 battery repair workers). Engineering controls and respiratory protection were judged to be inadequate at battery manufacturers and battery repair shops. At manufacturers, 38 of 42 air samples for lead exceeded a work-shift time-weighted average concentration of 0.050 mg/m3 (range 0.030-5.3 mg/m3), and nine samples exceeded 0.50 mg/m3. Only one of seven air samples at repair shops exceeded 0.050 mg/m3 (range 0.003-0.066 mg/m3). Repair shop workers, however, had higher blood lead levels than manufacturing workers (65% vs. 28% with blood lead levels above 60 micrograms/dl, respectively). Manufacturing workers had a higher prevalence of safe hygienic practices and a recent interval of minimal production had occurred at one of the battery manufacturers. Workers with blood lead levels above 60 micrograms/dl tended to have higher prevalences of most symptoms of lead toxicity than did workers with lower blood lead levels, but this finding was not consistent or statistically significant. The relationship between zinc protoporphyrin concentrations and increasing blood lead concentrations was consistent with that described among workers in developed countries. The high risk of lead toxicity among Jamaican battery workers is consistent with studies of battery workers in other developing countries.

  15. Primer on lead-acid storage batteries

    SciTech Connect

    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.

  16. Lightweight, durable lead-acid batteries

    DOEpatents

    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).

  17. Lightweight, durable lead-acid batteries

    DOEpatents

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

    2011-09-13

    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).

  18. The European lead/acid battery industry

    NASA Astrophysics Data System (ADS)

    Claudel, J. L.

    The European lead/acid battery industry is examined from a general perspective that covers wide economic, industrial and technical issues. It would appear that the upheavals witnessed in Eastern Europe two years ago together with the more recent political and monetary events throw two points into sharp relief: first, the merely relative value of general speeches, that are liable to sound technocratic and out of touch with the realities of the world; second, the need for an industrialist to be able to stand back and view things from a distance. Given this background, the review is divided into four parts, namely: (i) general remarks about Europe; (ii) the wider context of the lead/acid battery industry; (iii) changes in demand; (iv) structural changes in market supply. Finally, a number of observations are made about the key issues that will prove decisive for the future of battery manufacturers in Europe within the context of a rapidly changing environment.

  19. Closure device for lead-acid batteries

    DOEpatents

    Ledjeff, Konstantin

    1983-01-01

    A closure device for lead-acid batteries includes a filter of granulated activated carbon treated to be hydrophobic combined with means for preventing explosion of emitted hydrogen and oxygen gas. The explosion prevention means includes a vertical open-end tube within the closure housing for maintaining a liquid level above side wall openings in an adjacent closed end tube. Gases vent from the battery through a nozzle directed inside the closed end tube against an impingement surface to remove acid droplets. The gases then flow through the side wall openings and the liquid level to quench any possible ignition prior to entering the activated carbon filter. A wick in the activated carbon filter conducts condensed liquid back to the closure housing to replenish the liquid level limited by the open-end tube.

  20. Relativity and the lead-acid battery.

    PubMed

    Ahuja, Rajeev; Blomqvist, Andreas; Larsson, Peter; Pyykkö, Pekka; Zaleski-Ejgierd, Patryk

    2011-01-07

    The energies of the solid reactants in the lead-acid battery are calculated ab initio using two different basis sets at nonrelativistic, scalar-relativistic, and fully relativistic levels, and using several exchange-correlation potentials. The average calculated standard voltage is 2.13 V, compared with the experimental value of 2.11 V. All calculations agree in that 1.7-1.8 V of this standard voltage arise from relativistic effects, mainly from PbO2 but also from PbSO4.

  1. Relativity and the Lead-Acid Battery

    NASA Astrophysics Data System (ADS)

    Ahuja, Rajeev; Blomqvist, Andreas; Larsson, Peter; Pyykkö, Pekka; Zaleski-Ejgierd, Patryk

    2011-01-01

    The energies of the solid reactants in the lead-acid battery are calculated ab initio using two different basis sets at nonrelativistic, scalar-relativistic, and fully relativistic levels, and using several exchange-correlation potentials. The average calculated standard voltage is 2.13 V, compared with the experimental value of 2.11 V. All calculations agree in that 1.7-1.8 V of this standard voltage arise from relativistic effects, mainly from PbO2 but also from PbSO4.

  2. Advances in the biology and chemistry of sialic acids.

    PubMed

    Chen, Xi; Varki, Ajit

    2010-02-19

    Sialic acids are a subset of nonulosonic acids, which are nine-carbon alpha-keto aldonic acids. Natural existing sialic acid-containing structures are presented in different sialic acid forms, various sialyl linkages, and on diverse underlying glycans. They play important roles in biological, pathological, and immunological processes. Sialobiology has been a challenging and yet attractive research area. Recent advances in chemical and chemoenzymatic synthesis, as well as large-scale E. coli cell-based production, have provided a large library of sialoside standards and derivatives in amounts sufficient for structure-activity relationship studies. Sialoglycan microarrays provide an efficient platform for quick identification of preferred ligands for sialic acid-binding proteins. Future research on sialic acid will continue to be at the interface of chemistry and biology. Research efforts not only will lead to a better understanding of the biological and pathological importance of sialic acids and their diversity but also could lead to the development of therapeutics.

  3. Failure modes of lead/acid batteries

    NASA Astrophysics Data System (ADS)

    Culpin, B.; Rand, D. A. J.

    The delivery and storage of electrical energy in lead/acid batteries via the conversion of lead dioxide and lead to, and from, lead sulphate is deceptively simple. In fact, battery performance depends upon the cell design, the materials of construction, a complex interplay between the multitudinous parameters involved in plate preparation, the chemical composition/structure of the active materials, and the duty/conditions of battery operation. It is not surprising, therefore, that the factors responsible for the degradation of battery performance, and eventual failure, are many and varied. Apart from occasional field surveys of automotive batteries in the U.S.A., comprehensive failure analyses of units removed from service are rarely published. In general, the information is kept proprietary, or appears as a post mortem report that is subsidiary to some other topic of interest. By contrast, the literature abounds with detailed laboratory investigations of phenomena that are likely to contribute, wholly or in part, to the demise of batteries. In broad terms, this review draws together the fragmented and scattered data presently available on the failure mechanisms of lead/acid batteries in order to provide a platform for further exploration of the phenomena, and for the planning of remedial strategies. The approach taken is to classify, first, the different lead/acid technologies in terms of required duty (i.e., float, cycling and automotive applications), unit design (i.e., flat or tubular plate, flooded or immobilized electrolyte), and grid alloy (i.e., leadantimony or leadcalcium system). A distinction is then made between catastrophic failure, as characterized by a sudden inability of the battery to function, and progressive failure, as demonstrated by some more subtle deviation from optimum performance. Catastrophic failure is attributed to incorrect cell design, poor manufacturing practice, abuse, or misuse. These problems are obvious and, accordingly

  4. Valve-regulated lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Berndt, D.

    Valve-regulated lead-acid (VRLA) batteries with gelled electrolyte appeared as a niche market during the 1950s. During the 1970s, when glass-fiber felts became available as a further method to immobilize the electrolyte, the market for VRLA batteries expanded rapidly. The immobilized electrolyte offers a number of obvious advantages including the internal oxygen cycle which accommodates the overcharging current without chemical change within the cell. It also suppresses acid stratification and thus opens new fields of application. VRLA batteries, however, cannot be made completely sealed, but require a valve for gas escape, since hydrogen evolution and grid corrosion are unavoidable secondary reactions. These reactions result in water loss, and also must be balanced in order to ensure proper charging of both electrodes. Both secondary reactions have significant activation energies, and can reduce the service life of VRLA batteries, operated at elevated temperature. This effect can be aggravated by the comparatively high heat generation caused by the internal oxygen cycle during overcharging. Temperature control of VRLA batteries, therefore, is important in many applications.

  5. Prospects for lead-acid batteries in the new millenium

    NASA Astrophysics Data System (ADS)

    Razelli, Eugenio

    The European lead-acid battery industry has been adversely affected by the collapse of the telecommunications and information technology expansion of the last several years and by general economic conditions in other sectors. This has had a substantial effect on the industrial battery market, particularly standby batteries, but the automotive business has been less affected. The industry has reacted to these continuing changes by consolidation and specialisation within the different sectors but this alone is insufficient to ensure future success. The industry faces significant challenges to improve efficiencies through better manufacturing systems, but the development of new products for both existing and future applications is the greater priority. Advanced automotive batteries for Powernet applications and for hybrid electric vehicles, new types of standby and traction batteries and improvements to automotive batteries can all be achieved with lead-acid technology. This is a system with enormous potential for further improvement building on current strengths. This is a challenge to which the industry must respond in order to underpin the lead-acid battery as the most important electrical energy storage system.

  6. Handheld advanced nucleic acid analyzer

    NASA Astrophysics Data System (ADS)

    Benett, William J.; Richards, James B.; Stratton, Paul; Hadley, Dean R.; Bodtker, Brian H.; Nasarabadi, Shanavaz L.; Milanovich, Fred P.; Mariella, Raymond P., Jr.; Koopman, Ronald P.; Belgrader, Philip

    2000-12-01

    There is a growing need for portable, lightweight, battery operated instruments capable of detecting and identifying bio-warfare and bio-terrorism agents in the field. To address this need, we have developed a handheld PCR instrument. LLNLs advanced thermal cycling technology and expertise with portable, field tested biological instrumentation, combined with the development of real-time, fluorescence based PCR assays, has enabled the development of a very portable, versatile, power efficient PCR instrument with a simplified operating system designed for use by first responders. The heart of the instrument is the sample module, which incorporates the advanced silicon thermal cycler developed at LLNL.

  7. Lead acetate trihydrate precursor route to synthesize novel ultrafine lead oxide from spent lead acid battery pastes

    NASA Astrophysics Data System (ADS)

    Sun, Xiaojuan; Yang, Jiakuan; Zhang, Wei; Zhu, Xinfeng; Hu, Yuchen; Yang, Danni; Yuan, Xiqing; Yu, Wenhao; Dong, Jinxin; Wang, Haifeng; Li, Lei; Vasant Kumar, R.; Liang, Sha

    2014-12-01

    A novel green recycling process is investigated to prepare lead acetate trihydrate precursors and novel ultrafine lead oxide from spent lead acid battery pastes. The route contains the following four processes. (1) The spent lead pastes are desulphurized by (NH4)2CO3. (2) The desulphurized pastes are converted into lead acetate solution by leaching with acetic acid solution and H2O2; (3) The Pb(CH3COO)2·3H2O precursor is crystallized and purified from the lead acetate solution with the addition of glacial acetic acid; (4) The novel ultrafine lead oxide is prepared by the calcination of lead acetate trihydrate precursor in N2 or air at 320-400 °C. Both the lead acetate trihydrate and lead oxide products are characterized by TG-DTA, XRD, and SEM techniques. The calcination products are mainly α-PbO, β-PbO, and a small amount of metallic Pb. The particle size of the calcination products in air is significantly larger than that in N2. Cyclic voltammetry measurements of the novel ultrafine lead oxide products show good reversibility and cycle stability. The assembled batteries using the lead oxide products as cathode active materials show a good cyclic stability in 80 charge/discharge cycles with the depth of discharge (DOD) of 100%.

  8. Advances in the Biology and Chemistry of Sialic Acids

    PubMed Central

    Chen, Xi; Varki, Ajit

    2010-01-01

    Sialic acids are a subset of nonulosonic acids, which are nine-carbon alpha-keto aldonic acids. Natural existing sialic acid-containing structures are presented in different sialic acid forms, various sialyl linkages, and on diverse underlying glycans. They play important roles in biological, pathological, and immunological processes. Sialobiology has been a challenging and yet attractive research area. Recent advances in chemical and chemoenzymatic synthesis as well as large-scale E. coli cell-based production have provided a large library of sialoside standards and derivatives in amounts sufficient for structure-activity relationship studies. Sialoglycan microarrays provide an efficient platform for quick identification of preferred ligands for sialic acid-binding proteins. Future research on sialic acid will continue to be at the interface of chemistry and biology. Research efforts will not only lead to a better understanding of the biological and pathological importance of sialic acids and their diversity, but could also lead to the development of therapeutics. PMID:20020717

  9. Study on sources of charging lead acid batteries

    NASA Astrophysics Data System (ADS)

    Diniş, C. M.; Popa, G. N.; Iagăr, A.

    2015-06-01

    The paper presents the general characteristics of lead acid batteries and two charging methods of these batteries. For charging of lead batteries was used an intelligent power source K 8012 (from Velleman). The power source allows fixing the level of the battery voltage and battery capacity. The intelligent power source uses the joint method (at constant current and, then, at constant voltage) and warning that indicates different situations in the charging process. Other method of charging presented in the paper is at constant voltage using a stabilized power source. In the paper experimental measurements were carried out using data acquisition card SER 10 BIT (from Conrad) for charging/ discharging of a lead acid battery 12V/9Ah (using an intelligent power source) and charging of another high capacity lead acid battery 12V/47Ah/390 A (using a stabilized power source). At the discharging of the lead acid batteries it were used automotive lamps as electric loads.

  10. Effect of mixed additives on lead-acid battery electrolyte

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Arup; Basumallick, Indra Narayan

    This paper describes the corrosion behaviour of the positive and negative electrodes of a lead-acid battery in 5 M H 2SO 4 with binary additives such as mixtures of phosphoric acid and boric acid, phosphoric acid and tin sulphate, and phosphoric acid and picric acid. The effect of these additives is examined from the Tafel polarisation curves, double layer capacitance and percentage of inhibition efficiency. A lead salt battery has been fabricated replacing the binary mixture with an alternative electrolyte and the above electrochemical parameters have been evaluated for this lead salt battery. The results are explained in terms of H + ion transport and the morphological change of the PbSO 4 layer.

  11. Development of new sealed bipolar lead-acid battery

    NASA Technical Reports Server (NTRS)

    Attia, Alan I.; Rowlette, J. J.

    1987-01-01

    New light weight composite bipolar plates which can withstand the corrosive environment of the lead acid battery have made possible the construction of a sealed bipolar lead acid battery that promises to achieve very high specific power levels and substantially higher energy densities than conventional lead acid batteries. Performance projections based on preliminary experimental results show that the peak specific power of the battery can be as high as 90 kW/kg, and that a specific power of 5 kW/kg can be sustained over several thousand pulses.

  12. Lightweight, High-Energy Lead/Acid Battery

    NASA Technical Reports Server (NTRS)

    Rippel, Wally E.; Edwards, Dean B.

    1991-01-01

    Concept for lead/acid battery calls for woven-grid bipolar electrodes. Stack of bipolar cells form lead/acid battery. Each cell contains pair of folded electrodes, negative on one side of fold, positive on other. In high-voltage configuration, battery has higher specific energy and power. Rugged, longlived, and maintenance-free. Made from readily available, low-cost materials by standard lead/acid production methods, well suited for use in electronic equipment, aircraft, and electric vehicles for industrial and passenger service.

  13. Fatty Acid Desaturases, Polyunsaturated Fatty Acid Regulation, and Biotechnological Advances

    PubMed Central

    Lee, Je Min; Lee, Hyungjae; Kang, SeokBeom; Park, Woo Jung

    2016-01-01

    Polyunsaturated fatty acids (PUFAs) are considered to be critical nutrients to regulate human health and development, and numerous fatty acid desaturases play key roles in synthesizing PUFAs. Given the lack of delta-12 and -15 desaturases and the low levels of conversion to PUFAs, humans must consume some omega-3 and omega-6 fatty acids in their diet. Many studies on fatty acid desaturases as well as PUFAs have shown that fatty acid desaturase genes are closely related to different human physiological conditions. Since the first front-end desaturases from cyanobacteria were cloned, numerous desaturase genes have been identified and animals and plants have been genetically engineered to produce PUFAs such as eicosapentaenoic acid and docosahexaenoic acid. Recently, a biotechnological approach has been used to develop clinical treatments for human physiological conditions, including cancers and neurogenetic disorders. Thus, understanding the functions and regulation of PUFAs associated with human health and development by using biotechnology may facilitate the engineering of more advanced PUFA production and provide new insights into the complexity of fatty acid metabolism. PMID:26742061

  14. Fatty Acid Desaturases, Polyunsaturated Fatty Acid Regulation, and Biotechnological Advances.

    PubMed

    Lee, Je Min; Lee, Hyungjae; Kang, SeokBeom; Park, Woo Jung

    2016-01-04

    Polyunsaturated fatty acids (PUFAs) are considered to be critical nutrients to regulate human health and development, and numerous fatty acid desaturases play key roles in synthesizing PUFAs. Given the lack of delta-12 and -15 desaturases and the low levels of conversion to PUFAs, humans must consume some omega-3 and omega-6 fatty acids in their diet. Many studies on fatty acid desaturases as well as PUFAs have shown that fatty acid desaturase genes are closely related to different human physiological conditions. Since the first front-end desaturases from cyanobacteria were cloned, numerous desaturase genes have been identified and animals and plants have been genetically engineered to produce PUFAs such as eicosapentaenoic acid and docosahexaenoic acid. Recently, a biotechnological approach has been used to develop clinical treatments for human physiological conditions, including cancers and neurogenetic disorders. Thus, understanding the functions and regulation of PUFAs associated with human health and development by using biotechnology may facilitate the engineering of more advanced PUFA production and provide new insights into the complexity of fatty acid metabolism.

  15. Nanocrosses of lead sulphate as the negative active material of lead acid batteries

    NASA Astrophysics Data System (ADS)

    Liu, Yi; Gao, Pengran; Bu, Xianfu; Kuang, Guizhi; Liu, Wei; Lei, Lixu

    2014-10-01

    Lead sulphate transforms into PbO2 and Pb in the positive and negative electrodes, respectively, when a lead acid battery is charged, thus, it is an active material. It is also generally acknowledged that sulphation results in the failure of lead acid batteries; therefore, it is very interesting to find out how to make lead sulphate more electrochemically active. Here, we demonstrate that nanocrystalline lead sulphate can be used as excellent negative active material in lead acid batteries. The lead sulphate nanocrystals, which are prepared by a facile chemical precipitation of aqueous lead acetate and sodium sulphate in a few minutes, look like crosses with diameter of each arm being 100 nm to 3 μm. The electrode is effectively formed in much shorter time than traditional technique, yet it discharges a capacity of 103 mA h g-1 at the current density of 120 mA g-1, which is 24% higher than that discharged by the electrode made from leady oxide under the same condition. During 100% DOD cycles, more than 80% of that capacity remains in 550 cycles. These results show that lead sulphate can be a nice negative active material in lead acid batteries.

  16. Anaerobic microbial dissolution of lead and production of organic acids

    DOEpatents

    Francis, A.J.; Dodge, C.; Chendrayan, K.; Quinby, H.L.

    1987-04-16

    The present invention related to an anaerobic bacterial culture of Clostridium sp. ATCC No. 53464 which solubilizes lead oxide under anaerobic conditions in coal and industrial wastes and therefore presents a method of removing lead from such wastes before they are dumped into the environment. The rat of lead dissolution during logarithmic growth of the bacteria in 40 ml medium containing 3.32 ..mu..moles of lead as lead oxide was 0.042 ..mu..moles m1/sup /-/1/ hr/sup /-/1/. Dissolution of lead oxide by the bacterial isolate is due to the production of metabolites and acidity in the culture medium. The major metabolites are acetic, butyric and lactic acid. The major metabolites are acetic, butyric and lactic acid. Clostridium sp. ATCC No. 53464 can be used in the recovery of the strategic metals from ores and wastes and also for the production of lactic acid for commercial purposes. The process yields large quantities of lactic acid as well as lead complexed in a stable form with said acids. 4 figs., 3 tabs.

  17. Recovery of lead from lead paste in spent lead acid battery by hydrometallurgical desulfurization and vacuum thermal reduction.

    PubMed

    Ma, Yunjian; Qiu, Keqiang

    2015-06-01

    Lead sulfate, lead oxides and lead metal are the main component of lead paste in spent lead acid battery. When lead sulfate was desulfurized and transformed into lead carbonate by sodium carbonate, lead metal and lead oxides remained unchanged. Lead carbonate is easily decomposed to lead oxide and carbon dioxide under high temperature. Namely, vacuum thermal process is the reduction reaction of lead oxides. A compatible environmental process consisted of hydrometallurgical desulfurization and vacuum thermal reduction to recycle lead was investigated in this research. Lead paste was firstly desulfurized with sodium carbonate, by which, the content of sulfur declined from 7.87% to 0.26%. Then, the desulfurized lead paste was reduced by charcoal under vacuum. Under the optimized reaction conditions, i.e., vacuum thermal reduction at temperature 850°C under 20 Pa for 45 min, a 22.11×10(-2) g cm(-2) min(-1) reduction rate, and a 98.13% direct recovery ratio of fine lead (99.77%) had been achieved, respectively.

  18. "Stratifiability index" - A quantitative assessment of acid stratification in flooded lead acid batteries

    NASA Astrophysics Data System (ADS)

    Schulte, Dominik; Sauer, Dirk Uwe; Ebner, Ellen; Börger, Alexander; Gose, Sven; Wenzl, Heinz

    2014-12-01

    A methodology is presented to quantify acid stratification in flooded lead acid batteries and compare different types of batteries regardless of their design features and size by means of the proposed "stratifiability index". This index describes to what degree acid stratification develops in flooded lead acid batteries. Different test procedures are proposed which induce severe acid stratification within 48 h and lead to significantly different degrees of acid stratification. The test procedures are intended to assist in the development and selection of batteries which are less prone to develop severe acid stratification.

  19. Durable Bipolar Plates For Lead/Acid Batteries

    NASA Technical Reports Server (NTRS)

    Clough, Thomas J.; Pinsky, Naum

    1990-01-01

    New structure for positive faces of bipolar plates increases longevity of lead/acid batteries. Divides positive-electrode layer into many isolated segments so defects cannot spread across layer. Surfaces treated before assembly to promote adhesion. Ridges on body divide possible electrode into isolated squares, each typically 1 in. on side. Materials supporting electrochemically active components lightweight and resistant to acid.

  20. Anaerobic microbial dissolution of lead and production of organic acids

    DOEpatents

    Francis, Arokiasamy J.; Dodge, Cleveland; Chendrayan, Krishnachetty; Quinby, Helen L.

    1988-01-01

    The present invention relates to an anaerobic bacterial culture of Clostridium sp. ATCC No. 53464 which solubilizes lead oxide under anaerobic conditions in coal and industrial wastes and therefore presents a method of removing lead from such wastes before they are dumped into the environment. The rate of lead dissolution during logarithmic growth of the bacteria in 40 ml medium containing 3.32 .mu.moles of lead as lead oxide was 0.042 .mu.moles ml.sup.-1 hr.sup.-1. Dissolution of lead oxide by the bacterial isolate is due to the production of metabolites and acidity in the culture medium. The major metabolites are acetic, butyric and lactic acid. Clostridium sp. ATCC No. 53464 can be used in the recovery of strategic metals from ores and wastes and also for the production of lactic acid for commercial purposes. The process yields large quantities of lactic acid as well as lead complexed in a stable form with said acids.

  1. Advancing polymeric delivery systems amidst a nucleic acid therapy renaissance

    PubMed Central

    Burke, Paul A.; Pun, Suzie H.; Reineke, Theresa M.

    2013-01-01

    Nucleic acid therapeutics are attracting renewed interest due to recent clinical advances and product approvals. Most leading programs use chemical conjugates, or viral vectors in the case of gene therapy, while several use no delivery system at all. Polymer systems, which have been at the periphery of this renaissance, often involve greater molecular complexity than competing approaches, which must be justified by their advantages. Advanced analytical methods, along with biological tools for characterizing biotransformation and intracellular trafficking, are increasingly being applied to nucleic acid delivery systems including those based on polymers. These frontiers of investigation create the opportunity for an era where highly defined polymer compositions are optimized based on mechanistic insights in a way that has not been previously possible, offering the prospect of greater differentiation from alternatives. This will require integrated collaboration between polymer scientists and those from other disciplines. PMID:24683504

  2. Advanced Modeling Reconciles Counterintuitive Decisions in Lead Optimization.

    PubMed

    Fernández, Ariel; Scott, L Ridgway

    2017-01-06

    Lead optimization (LO) is essential to fulfill the efficacy and safety requirements of drug-based targeted therapy. The ease with which water may be locally removed from around the target protein crucially influences LO decisions. However, inferred binding sites often defy intuition and the resulting LO decisions are often counterintuitive, with nonpolar groups in the drug placed next to polar groups in the target. We first introduce biophysical advances to reconcile these apparent mismatches. We incorporate three-body energy terms that account for the net stabilization of preformed target structures upon removal of interfacial water concurrent with drug binding. These unexplored drug-induced environmental changes enhancing the target electrostatics are validated against drug-target affinity data, yielding superior computational accuracy required to improve drug design.

  3. A lead-207 nuclear magnetic resonance study of the complexation of lead by carboxylic acids and aminocarboxylic acids

    NASA Astrophysics Data System (ADS)

    Nakashima, Thomas T.; Rabenstein, Dallas L.

    The complexation of Pb(II) by carboxylic acids and aminocarboxylic acids was studied by 207Pb NMR. The results indicate that the 207Pb chemical shift provides a sensitive probe of the aqueous coordination chemistry of Pb(II). A single, exchange-averaged resonance is observed for lead in solutions containing Pb(NO 3) 2 and pivalic acid, acetic acid, formic acid, or chloroacetic acid, the chemical shift of which is sensitive to the Pb(NO 3) 2 to carboxylic acid ratio and to solution pH. Formation constants for the Pb(II)-carboxylate complexes were determined by fitting the chemical shift data to a model involving the complexes and ligand protonation. Chemical shift data for solutions containing Pb(NO 3) 2 and glycine, histidine, or glycylglycine indicate complexation of Pb(II) by the zwitterionic forms of these ligands. Formation constants for these complexes, which are difficult to study by other methods, were also determined from the chemical shift data. Complexation of Pb(II) by ethylenediaminetetraacetic acid, N-hydroxyethylethylenediaminetriacetic acid, nitrilotriacetic acid, and N-methyliminodiacetic acid causes a large deshielding of the 207Pb nucleus, e.g., the resonance for the ethylenediaminetetraacetic acid complex is deshielded by 2350 ppm. The chemical shift of the lead in these complexes is sensitive to protonation of the complex and to the formation of mixed complexes containing hydroxide ion.

  4. High performance positive electrode for a lead-acid battery

    NASA Technical Reports Server (NTRS)

    Kao, Wen-Hong (Inventor); Bullock, Norma K. (Inventor); Petersen, Ralph A. (Inventor)

    1994-01-01

    An electrode suitable for use as a lead-acid battery plate is formed of a paste composition which enhances the performance of the plate. The paste composition includes a basic lead sulfate, a persulfate and water. The paste may also include lead oxide and fibers. An electrode according to the invention is characterized by good strength in combination with high power density, porosity and surface area.

  5. Characterization of nano-lead-doped active carbon and its application in lead-acid battery

    NASA Astrophysics Data System (ADS)

    Hong, Bo; Jiang, Liangxing; Xue, Haitao; Liu, Fangyang; Jia, Ming; Li, Jie; Liu, Yexiang

    2014-12-01

    In this paper, nano-lead-doped active carbon (nano-Pb/AC) composite with low hydrogen evolution current for lead-acid battery was prepared by ultrasonic-absorption and chemical-precipitate method. The nano-Pb/AC composite was characterized by SEM, EDS and TEM. The electrochemical characterizations are performed by linear sweep voltammetry (LSV), electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) in a three-electrode system. Since intermediate adsorption is the rate-determining step, the hydrogen evolution reaction (HER) is markedly inhibited as the intermediate adsorption impedance of nano-Pb/AC increased. Meanwhile, the working potential of nano-Pb/AC is widened to the whole potential region of Pb negative plate (from -1.36 V to -0.86 V vs. Hg/HgSO4) in lead-acid battery. In addition, nano-Pb can improve the interfacial compatibility between AC and Pb paste, accordingly relieve the symptoms of carbon floatation. Finally, 2.0 V single-cell flooded lead-acid batteries with 1.0 wt.% nano-Pb/AC or 1.0 wt.% AC addition in negative active materials are assembled. The cell performances test results show that the 3 h rate capacity, quick charging performance, high current discharging performance and cycling performance of nano-Pb/AC modified battery are all improved compared with regular lead-acid battery and AC modified lead-acid battery.

  6. The impact of the new 36 V lead-acid battery systems on lead consumption

    NASA Astrophysics Data System (ADS)

    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.

  7. Simulation of lead-acid battery using model order reduction

    NASA Astrophysics Data System (ADS)

    Esfahanian, Vahid; Ansari, Amir Babak; Torabi, Farschad

    2015-04-01

    In this study, a reduced order model (ROM) based on proper orthogonal decomposition (POD) method has been applied to the coupled one-dimensional electrochemical transport equations in order to efficiently simulate lead-acid batteries, numerically. The governing equations, including conservation of charge in solid and liquid phases and conservation of species are solved simultaneously. The POD-based method for a lead-acid cell is used to simulate a discharge process to show the capability of the present method. The obtained results show that not only the POD-based ROM of lead-acid battery significantly decreases the computational time but also there is an excellent agreement with the results of previous computational fluid dynamics (CFD) models.

  8. Bipolar lead-acid battery for hybrid vehicles

    NASA Astrophysics Data System (ADS)

    Saakes, M.; Woortmeijer, R.; Schmal, D.

    Within the framework of the European project bipolar lead-acid power source (BILAPS), a new production route is being developed for the bipolar lead-acid battery. The performance targets are 500 W kg -1, 30 Wh kg -1 and 100 000 power-assist life cycles (PALCs). The operation voltage of the battery can be, according to the requirements, 12, 36 V or any other voltage. Tests with recently developed 4 and 12 V prototypes, each of 30 Ah capacity have demonstrated that the PALC can be operated using 10 C discharge and 9 C charge peaks. The tests show no overvoltage or undervoltage problems during three successive test periods of 16 h with 8 h rest in between. The temperature stabilizes during these tests at 40-45 °C using a thermal-management system. The bipolar lead acid battery is operated at an initial 50% state-of-charge. During the tests, the individual cell voltages display only very small differences. Tests are now in progress to improve further the battery-management system, which has been developed at the cell level, during the period no PALCs are run in order to improve the hybrid behaviour of the battery. The successful tests show the feasibility of operating the bipolar lead-acid battery in a hybrid mode. The costs of the system are estimated to be much lower than those for nickel-metal-hydride or Li-ion based high-power systems. An additional advantage of the lead-acid system is that recycling of lead-acid batteries is well established.

  9. Electrodeposited nanostructured lead dioxide as a thin film electrode for a lightweight lead-acid battery

    NASA Astrophysics Data System (ADS)

    Egan, D. R. P.; Low, C. T. J.; Walsh, F. C.

    Thin films of nanostructured lead dioxide are investigated as a positive electrode material for a lightweight lead-acid battery. The films are obtained by constant current deposition from electrolytes of lead methanesulfonate in methanesulfonic acid. The films are tested in two conditions namely (a) cyclic voltammetry and (b) constant current battery cycling in sulfuric acid. The charge and discharge current density, charge density and charge efficiency are measured as a function of cycle number. The effect of deposition conditions, such as solution temperature (295 and 333 K), type of substrate and electrolyte additive (hexadecyltrimethylammonium hydroxide), on the electrochemical performance of the PbO 2 in sulfuric acid is investigated. It is found that the as-deposited lead dioxide film is compact and nanostructured β-phase structure. Following successive cycling in sulfuric acid, the compact thin film gradually transforms into a porous microstructure consisting of positive active material (PbO 2 and PbSO 4), several tens of nanometres size. The charge density, discharge density and peak discharge current density of the PbO 2 improve with cycling of the thin film electrode.

  10. Charge Efficiency Tests of Lead/Acid Batteries

    NASA Technical Reports Server (NTRS)

    Rowlette, J. J.

    1984-01-01

    Current, voltage, and gas evolution measured during charge/discharge cycles. Series of standarized tests for evaluating charging efficiency of lead/acid storage batteries described in report. Purpose of tests to provide information for design of battery charger that allows maximum recharge efficiency for electric-vehicle batteries consistent with other operating parameters, such as range, water loss, and cycle life.

  11. Ocular trauma from lead-acid vehicle battery explosions.

    PubMed

    Siebert, S

    1982-02-01

    Ocular trauma caused by lead-acid car battery explosions has been seen in a number of cases presenting to the major teaching hospitals in Adelaide. Injuries range from superficial acid burns to penetrating eye injury and retinal haemorrhage. The cause of the explosions has been ignition of the hydrogen-oxygen gas mixture generated by lead-acid batteries. The risk of explosion is known to battery manufacturing and distributing bodies and methods of avoiding explosions are well known to the industry. It is suggested that efforts should be made to design safe car batteries, and that there is an urgent need to educate the public to the risks involved with the present batteries.

  12. Valproic acid, a molecular lead to multiple regulatory pathways.

    PubMed

    Kostrouchová, M; Kostrouch, Z; Kostrouchová, M

    2007-01-01

    Valproic acid (2-propyl pentanoic acid) is a drug used for the treatment of epilepsy and bipolar disorder. Although very rare, side effects such as spina bifida and other defects of neural tube closure indicate that valproic acid interferes with developmental regulatory pathways. Recently obtained data show that valproic acid affects cell growth, differentiation, apoptosis and immunogenicity of cultured cancer cells and tumours. Focused studies uncovered the potential of valproic acid to interfere with multiple regulatory mechanisms including histone deacetylases, GSK3 alpha and beta, Akt, the ERK pathway, the phosphoinositol pathway, the tricarboxylic acid cycle, GABA, and the OXPHOS system. Valproic acid is emerging as a potential anticancer drug and may also serve as a molecular lead that can help design drugs with more specific and more potent effects on the one side and drugs with wide additive but weaker effects on the other. Valproic acid is thus a powerful molecular tool for better understanding and therapeutic targeting of pathways that regulate the behaviour of cancer cells.

  13. Recent Advances in the Clinical Management of Lead Poisoning.

    PubMed

    Kianoush, Sina; Sadeghi, Mahmood; Balali-Mood, Mahdi

    2015-01-01

    Lead poisoning is a historic universal disease. Acute or chronic lead exposure may cause reversible or even permanent damages in human beings. Environmental lead exposure is a global health concern in children. Occupational lead poisoning is still a health issue, particularly in developing countries. During the last decades, new methods and medications have been advocated for the prevention and treatment of lead poisoning. This review deals mainly with recent developments in the management of lead poisoning. Sources of lead exposure are introduced, and methods for the primary prevention of lead poisoning are discussed. Details for the screening of adults and children are also explained to serve as a practical guideline for the secondary prevention. Standard chelation therapy in different groups and up-to-date less toxic new medications for the treatment of lead poisoning are finally discussed. Our published clinical research on the therapeutic effects of garlic tablets in mild to moderate occupational lead poisoning will also be discussed.

  14. Lead/acid batteries in systems to improve power quality

    NASA Astrophysics Data System (ADS)

    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.

  15. Therapeutic efficacy of dimercaptosuccinic acid and thiamine/ascorbic acid on lead intoxication in rats

    SciTech Connect

    Tandon, S.K.; Flora, S.J.S. )

    1989-11-01

    Thiamine, folic acid, pyridoxine and ascorbic acid either individually or in combination have been proven to be effective in reducing the toxic manifestations of lead and in enhancing the antidotal efficacy of CaNa{sub 2}EDTA. In a recent report from the authors' laboratory, it was observed that given combination of thiamine and ascorbic acid with thiol chelators improved the ability of the animals to excrete lead thereby reducing body lead burden. In view of the beneficial effect of these two vitamins, it was considered of interest to evaluate their potential to modify the prophylactic action of DMS in lead intoxication in rat after repeated administration.

  16. Associations of blood lead, dimercaptosuccinic acid-chelatable lead, and tibia lead with polymorphisms in the vitamin D receptor and [delta]-aminolevulinic acid dehydratase genes.

    PubMed Central

    Schwartz, B S; Lee, B K; Lee, G S; Stewart, W F; Simon, D; Kelsey, K; Todd, A C

    2000-01-01

    A cross-sectional study was performed to evaluate the influence of polymorphisms in the [delta]-aminolevulinic acid dehydratase (ALAD) and vitamin D receptor (VDR) genes on blood lead, tibia lead, and dimercaptosuccinic acid (DMSA)-chelatable lead levels in 798 lead workers and 135 controls without occupational lead exposure in the Republic of Korea. Tibia lead was assessed with a 30-min measurement by (109)Cd-induced K-shell X-ray fluorescence, and DMSA-chelatable lead was estimated as 4-hr urinary lead excretion after oral administration of 10 mg/kg DMSA. The primary goals of the analysis were to examine blood lead, tibia lead, and DMSA-chelatable lead levels by ALAD and VDR genotypes, controlling for covariates; and to evaluate whether ALAD and VDR genotype modified relations among the different lead biomarkers. There was a wide range of blood lead (4-86 microg/dL), tibia lead (-7-338 microg Pb/g bone mineral), and DMSA-chelatable lead (4.8-2,103 microg) levels among lead workers. Among lead workers, 9.9% (n = 79) were heterozygous for the ALAD(2) allele and there were no homozygotes. For VDR, 10.7% (n = 85) had the Bb genotype, and 0.5% (n = 4) had the BB genotype. Although the ALAD and VDR genes are located on different chromosomes, lead workers homozygous for the ALAD(1) allele were much less likely to have the VDR bb genotype (crude odds ratio = 0.29, 95% exact confidence interval = 0.06-0.91). In adjusted analyses, subjects with the ALAD(2) allele had higher blood lead levels (on average, 2.9 microg/dL, p = 0.07) but no difference in tibia lead levels compared with subjects without the allele. In adjusted analyses, lead workers with the VDR B allele had significantly (p < 0.05) higher blood lead levels (on average, 4.2 microg/dL), chelatable lead levels (on average, 37.3 microg), and tibia lead levels (on average, 6.4 microg/g) than did workers with the VDR bb genotype. The current data confirm past observations that the ALAD gene modifies the

  17. Research, development and demonstration of lead-acid batteries for electric vehicle propulsion. Annual report, 1979

    SciTech Connect

    Not Available

    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)

  18. Aging mechanisms and service life of lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Ruetschi, Paul

    In lead-acid batteries, major aging processes, leading to gradual loss of performance, and eventually to the end of service life, are: Anodic corrosion (of grids, plate-lugs, straps or posts). Positive active mass degradation and loss of adherence to the grid (shedding, sludging). Irreversible formation of lead sulfate in the active mass (crystallization, sulfation). Short-circuits. Loss of water. Aging mechanisms are often inter-dependent. For example, corrosion of the grids will lead to increased resistance to current flow, which will in turn impede proper charge of certain parts of the active mass, resulting in sulfation. Active mass degradation may lead to short-circuits. Sulfation may be the result of a loss of water, and so forth. The rates of the different aging processes strongly depend on the type of use (or misuse) of the battery. Over-charge will lead to accelerated corrosion and also to accelerated loss of water. With increasing depth-of-discharge during cycling, positive active mass degradation is accelerated. Some aging mechanisms are occurring only upon misuse. Short-circuits across the separators, due to the formation of metallic lead dendrites, for example, are usually formed only after (excessively) deep discharge. Stationary batteries, operated under float-charge conditions, will age typically by corrosion of the positive grids. On the other hand, service life of batteries subject to cycling regimes, will typically age by degradation of the structure of the positive active mass. Starter batteries are usually aging by grid corrosion, for instance in normal passenger car use. However, starter batteries of city buses, making frequent stops, may age (prematurely) by positive active mass degradation, because the batteries are subject to numerous shallow discharge cycles. Valve-regulated batteries often fail as a result of negative active mass sulfation, or water loss. For each battery design, and type of use, there is usually a characteristic

  19. 75 FR 22439 - Advance Notice of Proposed Rulemaking on Lead Emissions From Piston-Engine Aircraft Using Leaded...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-28

    ...EPA is issuing this Advance Notice of Proposed Rulemaking (ANPR) to describe information currently available and information being collected that will be used by the Administrator to issue a subsequent proposal regarding whether, in the Administrator's judgment, aircraft lead emissions from aircraft using leaded aviation gasoline (avgas) cause or contribute to air pollution which may......

  20. Lead/acid battery recycling and the new Isasmelt process

    NASA Astrophysics Data System (ADS)

    Ramus, K.; Hawkins, P.

    The recovery of lead/acid batteries has long been practised for economic reasons. More recently, battery recovery has also been influenced by environmental concerns, both in the general community and within the recycling plants. These influences will probably increase in the future. With these factors in mind, Britannia Refined Metals Ltd. introduced new technology for battery recycling at its Northfleet, UK operations in 1991. A process description of the Britannia Refined Metals Secondary Lead Operation, the reasons for selecting an Engitec CX battery breaking plant in combination with an Isasmelt Paste Smelting Furnace, and commissioning and current operation of the plant are discussed.

  1. Heat tolerance of automotive lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Albers, Joern

    Starter batteries have to withstand a quite large temperature range. In Europe, the battery temperature can be -30 °C in winter and may even exceed +60 °C in summer. In most modern cars, there is not much space left in the engine compartment to install the battery. So the mean battery temperature may be higher than it was some decades ago. In some car models, the battery is located in the passenger or luggage compartment, where ambient temperatures are more moderate. Temperature effects are discussed in detail. The consequences of high heat impact into the lead-acid battery may vary for different battery technologies: While grid corrosion is often a dominant factor for flooded lead-acid batteries, water loss may be an additional influence factor for valve-regulated lead-acid batteries. A model was set up that considers external and internal parameters to estimate the water loss of AGM batteries. Even under hot climate conditions, AGM batteries were found to be highly durable and superior to flooded batteries in many cases. Considering the real battery temperature for adjustment of charging voltage, negative effects can be reduced. Especially in micro-hybrid applications, AGM batteries cope with additional requirements much better than flooded batteries, and show less sensitivity to high temperatures than suspected sometimes.

  2. Continuing issues with Lead: Recent Advances in Detection

    PubMed Central

    Deibler, Kristine

    2014-01-01

    In the past Pb2+ has been used in many industries, including gasoline, piping, toys, paints, and more. The use of lead has led to a natural increase of lead concentration in the environment especially in air and water. According to the U.S. CDC “no level of lead in blood is considered safe.” Exposure to very low amounts of lead can cause several health complications including developmental and neurological disorders. Over the past several years an emphasis has been placed in developing systems that can detect lead at a very low concentration. A great deal of work has been accomplished in the development of Pb2+ sensors that can not only detect but also quantify the amount and in some cases in the presence of other metal ions. Herein, we describe current regulations, mode of exposure and recent development of sensing techniques. PMID:25089117

  3. Processing of wastes from lead/acid battery production

    NASA Astrophysics Data System (ADS)

    Polivianny, I. R.; Rusin, A. I.; Lata, V. A.; Khegay, L. D.; Nourjigitov, S. T.

    Experience in the recovery of scrap and wastes from lead/acid battery production suggests that an electrothermal method has good prospects. This process is characterized by a high degree of lead and antimony (approx 98%) extraction, by effective gas cleaning and dust collection, and by full dust returning to the furnace. The electrothermal method is also distinguished by the high reliability of electric furnaces, the useability of any type of secondary lead battery scrap and wastes, and the possibility of process mechanization and control. In this paper, a description is given of the main technical and economical factors of soda-reduction smelting in an electric furnace, a technological scheme for wastes recovery, and the charge composition and features of the process.

  4. The Future of Nursing: Leading Change, Advancing Health

    ERIC Educational Resources Information Center

    National Academies Press, 2011

    2011-01-01

    "The Future of Nursing" explores how nurses' roles, responsibilities, and education should change significantly to meet the increased demand for care that will be created by health care reform and to advance improvements in America's increasingly complex health system. At more than 3 million in number, nurses make up the single…

  5. Lead-Free vs Tin-Lead Reliability of Advanced Electronic Assemblies

    NASA Technical Reports Server (NTRS)

    Ghaffarian, Reza

    2005-01-01

    This presentation will provide the technical background and specific information published in literature related to reliability test, analyses, modeling, and associated issues for lead-free solder package assemblies in comparison to their tin-lead solder alloys. It also presents current understanding of lead-free thermal cycle test performance in support.

  6. Lead and δ-Aminolevulinic Acid Dehydratase Polymorphism: Where Does It Lead? A Meta-Analysis

    PubMed Central

    Scinicariello, Franco; Murray, H. Edward; Moffett, Daphne B.; Abadin, Henry G.; Sexton, Mary J.; Fowler, Bruce A.

    2007-01-01

    Background Lead poisoning affects many organs in the body. Lead inhibits δ-aminolevulinic acid dehydratase (ALAD), an enzyme with two co-dominantly expressed alleles, ALAD1 and ALAD2. Objective Our meta-analysis studied the effects of the ALAD polymorphism on a) blood and bone lead levels and b) indicators of target organ toxicity. Data source We included studies reporting one or more of the following by individuals with genotypes ALAD1-1 and ALAD1-2/2-2: blood lead level (BLL), tibia or trabecular lead level, zinc protoporphyrin (ZPP), hemoglobin, serum creatinine, blood urea nitrogen (BUN), dimercaptosuccinic acid–chelatable lead, or blood pressure. Data extraction Sample sizes, means, and standard deviations were extracted for the genotype groups. Data synthesis There was a statistically significant association between ALAD2 carriers and higher BLL in lead-exposed workers (weighted mean differences of 1.93 μg/dL). There was no association with ALAD carrier status among environmentally exposed adults with BLLs < 10 μg/dL. ALAD2 carriers were potentially protected against adverse hemapoietic effects (ZPP and hemoglobin levels), perhaps because of decreased lead bioavailability to heme pathway enzymes. Conclusion Carriers of the ALAD2 allele had higher BLLs than those who were ALAD1 homozygous and higher hemoglobin and lower ZPP, and the latter seems to be inversely related to BLL. Effects on other organs were not well delineated, partly because of the small number of subjects studied and potential modifications caused by other proteins in target tissues or by other polymorphic genes. PMID:17366816

  7. System for agitating the acid in a lead-acid battery

    DOEpatents

    Weintraub, Alvin; MacCormack, Robert S.

    1987-01-01

    A system and method for agitating the acid in a large lead-sulfuric acid storage battery of the calcium type. An air-lift is utilized to provide the agitation. The air fed to the air-lift is humidified prior to being delivered to the air-lift.

  8. Elecrokinetic separation of sulphate and lead from sludge of spent lead acid battery.

    PubMed

    Maruthamuthu, S; Dhanibabu, T; Veluchamy, A; Palanichamy, S; Subramanian, P; Palaniswamy, N

    2011-10-15

    A novel electrokinetic (EK) technique is applied to separate lead and sulphate from the sludge of used/spent lead acid battery. XRD reveals that the sludge is a mixture of (PbO)(4) [Pb(SO(4))], Pb(2)O(3), PbSO(4), Pb(S(2)O(3)) and Pb(2)(SO(4)) which upon DC voltage application in a EK cell employing either titanium electrodes or titanium substrate insoluble anode as electrodes caused migration of sulphates and lead ions respectively into anode and cathode compartments, and accumulation of insoluble lead oxides at the central compartment. The insoluble lead oxides accumulated at the central compartment in the ratio 1:3, respectively for the high oxygen over-voltage Ti-anode (Ti-EK cell) and low oxygen over-voltage TSIA-anode (TSIA-EK cell) shows the superiority of Ti anode over TSIA anode. Also thermal investigation reveals Pb deposited at Ti-cathode is superior to that from TSIA cathode. This process does not release air/soil pollutants which are usually associated with high temperature pyrotechnic process.

  9. Stibine/arsine emissions from lead-acid batteries

    SciTech Connect

    Varma, R.; Cook, G. M.; Yao, N. P.

    1980-01-01

    Antimonial lead alloys, which also contain some arsenic, have traditionally been used for the fabrication of lead-acid battery electrodes. The possible generation of arsine and stibine during battery operation must be considered in the development of batteries for electric vehicles, utility load-leveling, and solar electricity storage. Research on generation of arsine and stibine is summarized, and exposure limits are given. Published analytical procedures for determination of arsine and stibine and their sensitivities are discussed. The design and testing of a stibine/arsine monitoring field kit are described. A hydrogen-oxygen recombination device can recombine stoichiometric H/sub 2/-O/sub 2/ with about 97% efficiency while scavenging the charge gas of much of the SbH/sub 3/ and AsH/sub 3/; its principles are illustrated. Experiments to estimate exposure of drivers to AsH/sub 3/ and SbH/sub 3/ from lead-acid batteries in electric vehicles are under way. 4 figures, 2 tables. (RWR)

  10. Spent lead-acid battery recycling in China - A review and sustainable analyses on mass flow of lead.

    PubMed

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

    2017-03-15

    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.

  11. Electrochemical and Mechanical Behavior of Lead-Silver and Lead-Bismuth Casting Alloys for Lead-Acid Battery Components

    NASA Astrophysics Data System (ADS)

    Osório, Wislei R.; Peixoto, Leandro C.; Garcia, Amauri

    2015-09-01

    The present study focuses on the interrelation of microstructure, mechanical properties, and corrosion resistance of Pb-Ag and Pb-Bi casting alloys, which can be used in the manufacture of lead-acid battery components, as potential alternatives to alloys currently used. A water-cooled solidification system is used, in which vertical upward directional solidification is promoted permitting a wide range of microstructures to be investigated. Correlations between microstructural arrays, tensile strengths, and corrosion resistances of Pb-1 wt pct Ag, Pb-2.5 wt pct Ag, Pb-1 wt pct Bi, and Pb-2.5 wt pct Bi alloys are envisaged. It is shown that a compromise between corrosion resistance (represented by the corrosion current density) and mechanical properties (represented by the ultimate tensile strength) can be obtained. Comparisons between specific strengths and mechanical/corrosion ratios are also made. It is also shown that, for microstructures solidified under cooling rates higher than 10 K/s, the Pb-Ag alloys exhibit higher specific strength and mechanical/corrosion ratio. In contrast, for casting processes in which the cooling rates are lower than 5 K/s, the dilute Pb-Bi alloy ( i.e., 1 wt pct Bi) is shown to have more appropriate requirements for lead-acid battery components. Comparisons between specific strengths, mechanical/corrosion ratio, and relative weight and cost with Pb-Sn and Pb-Sb alloys are also made.

  12. 24 CFR 242.48 - Insured advances for certain equipment and long lead items.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 24 Housing and Urban Development 2 2012-04-01 2012-04-01 false Insured advances for certain equipment and long lead items. 242.48 Section 242.48 Housing and Urban Development Regulations Relating to... for certain equipment and long lead items. The Commissioner may allow advances for certain pieces...

  13. Blood lead levels among rural Thai children exposed to lead-acid batteries from solar energy conversion systems.

    PubMed

    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.

  14. Advances in nucleic acid-based detection methods.

    PubMed Central

    Wolcott, M J

    1992-01-01

    Laboratory techniques based on nucleic acid methods have increased in popularity over the last decade with clinical microbiologists and other laboratory scientists who are concerned with the diagnosis of infectious agents. This increase in popularity is a result primarily of advances made in nucleic acid amplification and detection techniques. Polymerase chain reaction, the original nucleic acid amplification technique, changed the way many people viewed and used nucleic acid techniques in clinical settings. After the potential of polymerase chain reaction became apparent, other methods of nucleic acid amplification and detection were developed. These alternative nucleic acid amplification methods may become serious contenders for application to routine laboratory analyses. This review presents some background information on nucleic acid analyses that might be used in clinical and anatomical laboratories and describes some recent advances in the amplification and detection of nucleic acids. PMID:1423216

  15. SREB States Lead the Nation in Advanced Placement and International Baccalaureate Programs. Challenge to Lead

    ERIC Educational Resources Information Center

    Collins, Crystal; Lenard, Matthew

    2007-01-01

    Advanced Placement (AP) and International Baccalaureate (IB) courses continue to receive national recognition for their rigorous curricula, and many colleges and universities award credit to students who score well on end-of-course exams in AP classes. Research suggests that students are better prepared for college if they take these courses and…

  16. An Exploratory Study Of Lead Recovery In Lead-Acid Battery Lifecycle In US Market: An Evidence-Based Approach

    EPA Science Inventory

    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 ra...

  17. [Recent advances in the study of new antifungal lead compounds].

    PubMed

    Wang, Sheng-zheng; Sheng, Chun-quan; Zhang, Wan-nian

    2010-08-01

    In recent years, the incidence and mortality rate of invasive fungal infection have increased dramatically, and it is of great significance to develop novel antifungal agents with new chemical structure and new mode of action. In this review, novel antifungal lead compounds reported from 2007 to 2009 are reviewed. Moreover, their chemical structures, antifungal activities and structure-activity relationships have been summarized, which can provide useful information for future study of antifungal agents.

  18. Spiral wound valve-regulated lead-acid batteries for hybrid vehicles

    NASA Astrophysics Data System (ADS)

    Soria, M. L.; Trinidad, F.; Lacadena, J. M.; Valenciano, J.; Arce, G.

    Future vehicle applications require the development of reliable and long life batteries operating under high-rate partial-state-of-charge (HRPSoC) working conditions. This paper updates work carried out to develop spiral wound valve-regulated lead-acid (VRLA) batteries for vehicles with different hybridisation degrees, ranging from stop-start to mild hybrid applications. Former work on design optimisation and active material formulations has been implemented in two spiral wound VRLA batteries, rated 12 V 50 Ah and 6 V 24 Ah, and these two products are currently being tested both in benches and in vehicles with different hybridisation degrees within a demonstration project funded by the Advanced Lead Acid Battery Consortium and in collaboration with several European vehicle and electrical component manufacturers.

  19. Removal of lead by apatite and its stability in the presence of organic acids.

    PubMed

    Katoh, Masahiko; Makimura, Akihiko; Sato, Takeshi

    2016-12-01

    In this study, lead sorption and desorption tests were conducted with apatite and organic acids (i.e. citric, malic, and formic acids) to understand lead removal by apatite in the presence of an organic acid and lead dissolution from the lead- and organic-acid-sorbed apatite by such organic acid exposure. The lead sorption test showed that the amount of lead removed by apatite in the presence of organic acid varied depending on the type of acid used. The molar amounts of calcium dissolved from apatite in the presence and absence of organic acid were exactly the same as those of lead removed even under different pH conditions as well as different organic acid concentrations, indicating that the varying amount of lead removal in the presence of different organic acids resulted from the magnitude of the dissolution of apatite and the precipitation of lead phosphate minerals. The percentages of lead dissolved from the organic-acid-sorbed and non-organic-acid-sorbed apatite by all the organic acid extractions were equal and higher than those by water extraction. In particular, the highest extractions were observed in the non-organic-acid-sorbed apatite by citric and malic acids. These results suggest that to immobilize lead by the use of apatite in the presence of organic acids, much more apatite must be added than in the absence of organic acid, and that measures must be taken to ensure that the immobilized lead is not dissolved.

  20. Recent trends in the advanced analysis of bioactive fatty acids.

    PubMed

    Ruiz-Rodriguez, Alejandro; Reglero, Guillermo; Ibañez, Elena

    2010-01-20

    The consumption of dietary fats have been long associated to chronic diseases such as obesity, diabetes, cancer, arthritis, asthma, and cardiovascular disease; although some controversy still exists in the role of dietary fats in human health, certain fats have demonstrated their positive effect in the modulation of abnormal fatty acid and eicosanoid metabolism, both of them associated to chronic diseases. Among the different fats, some fatty acids can be used as functional ingredients such as alpha-linolenic acid (ALA), arachidonic acid (AA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), gamma-linolenic acid (GLA), stearidonic acid (STA) and conjugated linoleic acid (CLA), among others. The present review is focused on recent developments in FAs analysis, covering sample preparation methods such as extraction, fractionation and derivatization as well as new advances in chromatographic methods such as GC and HPLC. Special attention is paid to trans fatty acids due its increasing interest for the food industry.

  1. Novel lead-graphene and lead-graphite metallic composite materials for possible applications as positive electrode grid in lead-acid battery

    NASA Astrophysics Data System (ADS)

    Yolshina, L. A.; Yolshina, V. A.; Yolshin, A. N.; Plaksin, S. V.

    2015-03-01

    Novel lead-graphene and lead-graphite metallic composites which melt at temperature of the melting point of lead were investigated as possible positive current collectors for lead acid batteries in sulfuric acid solution. Scanning electron microscopy, Raman spectroscopy, difference scanning calorimetry, cyclic voltammetry and prolonged corrosion tests were employed to characterize the effect of the newly proposed lead-carbon metallic composites on the structure and electrochemical properties of positive grid material. Both lead-graphene and lead-graphite metallic composite materials show the similar electrochemical characteristics to metallic lead in the voltage range where the positive electrodes of lead acid batteries operate. It has been shown that carbon both as graphene and graphite does not participate in the electrochemical process but improve corrosion and electrochemical characteristics of both metallic composite materials. No products of interaction of lead with sulfuric acid were formed on the surface of graphene and graphite so as it was not found additional peaks of carbon discharge on voltammograms which could be attributed to the carbon. Graphene inclusions in lead prevent formation of leady oxide nanocrystals which deteriorate discharge characteristics of positive electrode of LAB. Both lead-graphene alloy and lead-graphite metallic composite proved excellent electrochemical and corrosion behavior and can be used as positive grids in lead acid batteries of new generation.

  2. Improved lead recovery and sulphate removal from used lead acid battery through electrokinetic technique.

    PubMed

    Soundarrajan, C; Sivasankar, A; Maruthamuthu, S; Veluchamy, A

    2012-05-30

    This paper presents improvement in lead (Pb) recovery and sulphate removal from used Pb acid battery (ULAB) through Electrokinetic technique, a process aimed to eliminate environmental pollution that arises due to emission of gases and metal particles from the existing high temperature pyrometallurgical process. Two different cell configurations, (1) one with Nafion membrane placed between anode and middle compartments and Agar membrane between cathode and middle compartments and (2) another with only Agar membrane placed between both sides of the middle compartments were designed for the Pb and sulphate separation from ULAB. This paper concludes that the cell with only Agar membranes performed better than the cell with Nafion and Agar membranes in combinations and also explains the mechanism underlying the chemical and electrochemical processes in the cell.

  3. Premature capacity-loss mechanisms in lead/acid batteries

    NASA Astrophysics Data System (ADS)

    Hollenkamp, A. F.; Constanti, K. K.; Huey, A. M.; Koop, M. J.; Aputeanu, L.

    The phenomenon known as 'premature capacity loss' (PCL) causes the early demise of lead/acid batteries based on a variety of grid alloys. It is also known to be a problem specific to the positive plate and is usually invoked by duties that involve repetitive deep-discharge cycling. In order to determine the cause(s) of the problem, an extensive study of the behaviour of cells based on a range of positive grid alloys is being conducted. Examples of PCL have been generated by subjecting three-plate cells to 100% depth-of-discharge, at I = C8/8, with 110% overcharge. Cells based on antimony-free grids exhibit capacity loss at a rate of up to 5% of the initial capacity per cycle, with both constant-current and constant-voltage charging. With the latter charging method, most of the cells also develop extremely poor charge acceptance within 10 to 15 cycles. The performance of cells with high-antimony positive grids is significantly better, although substantial capacity loss is still observed. The latter cannot be explained by any of the classic failure modes for lead/acid batteries. Poor charge acceptance is not displayed by these cells. Plates show signs of physical degradation, but these represent a minor contribution to capacity loss. Phase composition of positive material does not vary with grid alloy and is typical of healthy plates. Investigations of corrosion-layer morphology have shown that Pb-Ca grids give rise to weak corrosion products that are prone to fracture and separation, while the corrosion layers on Pb-Sb plates are apparently more coherent and more strongly bonded to the underlying grid.

  4. Pulse charging of lead-acid traction cells

    NASA Astrophysics Data System (ADS)

    Smithrick, J. J.

    1980-05-01

    Pulse charging, as a method of rapidly and efficiently charging 300 amp-hour lead-acid traction cells for an electric vehicle application was investigated. A wide range of charge pulse current square waveforms were investigated and the results were compared to constant current charging at the time averaged pulse current values. Representative pulse current waveforms were: (1) positive waveform-peak charge pulse current of 300 amperes (amps), discharge pulse-current of zero amps, and a duty cycle of about 50%; (2) Romanov waveform-peak charge pulse current of 300 amps, peak discharge pulse current of 15 amps, and a duty of 50%; and (3) McCulloch waveform peak charge pulse current of 193 amps, peak discharge pulse current of about 575 amps, and a duty cycle of 94%. Experimental results indicate that on the basis of amp-hour efficiency, pulse charging offered no significant advantage as a method of rapidly charging 300 amp-hour lead-acid traction cells when compared to constant current charging at the time average pulse current value. There were, however, some disadvantages of pulse charging in particular a decrease in charge amp-hour and energy efficiencies and an increase in cell electrolyte temperature. The constant current charge method resulted in the best energy efficiency with no significant sacrifice of charge time or amp-hour output. Whether or not pulse charging offers an advantage over constant current charging with regard to the cell charge/discharge cycle life is unknown at this time.

  5. Pulse charging of lead-acid traction cells

    NASA Technical Reports Server (NTRS)

    Smithrick, J. J.

    1980-01-01

    Pulse charging, as a method of rapidly and efficiently charging 300 amp-hour lead-acid traction cells for an electric vehicle application was investigated. A wide range of charge pulse current square waveforms were investigated and the results were compared to constant current charging at the time averaged pulse current values. Representative pulse current waveforms were: (1) positive waveform-peak charge pulse current of 300 amperes (amps), discharge pulse-current of zero amps, and a duty cycle of about 50%; (2) Romanov waveform-peak charge pulse current of 300 amps, peak discharge pulse current of 15 amps, and a duty of 50%; and (3) McCulloch waveform peak charge pulse current of 193 amps, peak discharge pulse current of about 575 amps, and a duty cycle of 94%. Experimental results indicate that on the basis of amp-hour efficiency, pulse charging offered no significant advantage as a method of rapidly charging 300 amp-hour lead-acid traction cells when compared to constant current charging at the time average pulse current value. There were, however, some disadvantages of pulse charging in particular a decrease in charge amp-hour and energy efficiencies and an increase in cell electrolyte temperature. The constant current charge method resulted in the best energy efficiency with no significant sacrifice of charge time or amp-hour output. Whether or not pulse charging offers an advantage over constant current charging with regard to the cell charge/discharge cycle life is unknown at this time.

  6. Effect of iron doped lead oxide on the performance of lead acid batteries

    NASA Astrophysics Data System (ADS)

    Liu, Jianwen; Yang, Danni; Gao, Linxia; Zhu, Xinfeng; Li, Lei; Yang, Jiakuan

    2011-10-01

    In order to investigate effect of iron on the performance of lead acid batteries, we systematically study the chemical characteristics, electrochemical characteristics, battery capacity and cycle life using iron-doped lead oxide in this article. Cyclic voltammetry results show that positive discharge current decreases sharply with the increasing content of Fe2O3 from 0.05 wt.% to 2 wt.%. The release of H2 and O2 are promoted accompanying the increase of Fe2O3 contents. The chemical analysis confirms that the strength of Fe3+, Fe2+ concentration is simultaneously increased with the increase of iron contents after 50 voltammetry cycles. X-ray diffraction phase analysis shows that the amount of PbSO4 increases with the increasing iron content in the positive plates after 50 discharge cycles. Morphologies of positive plates show that many agglomerates from PbSO4 crystals appear. The SEM observations illustrate that there is a lower porosity and specific surface area in the positive active material with iron after 50 discharge cycles. The mechanism of iron decreasing capacity, cycle-life and promoting the release of H2 and O2 has been elucidated in details. We support it is the "redox-diffusion" process of multiple-valence iron and formation of PbSO4 on electrodes that result in above performances.

  7. Air and blood lead levels in lead acid battery recycling and manufacturing plants in Kenya.

    PubMed

    Were, Faridah H; Kamau, Geoffrey N; Shiundu, Paul M; Wafula, Godfrey A; Moturi, Charles M

    2012-01-01

    The concentration of airborne and blood lead (Pb) was assessed in a Pb acid battery recycling plant and in a Pb acid battery manufacturing plant in Kenya. In the recycling plant, full-shift area samples taken across 5 days in several production sections showed a mean value ± standard deviation (SD) of 427 ± 124 μg/m(3), while area samples in the office area had a mean ± SD of 59.2 ± 22.7 μg/m(3). In the battery manufacturing plant, full-shift area samples taken across 5 days in several production areas showed a mean value ± SD of 349 ± 107 μg/m(3), while area samples in the office area had a mean ± SD of 55.2 ± 33.2 μg/m(3). All these mean values exceed the U.S. Occupational Safety and Health Administration's permissible exposure limit of 50 μg/m(3) as an 8-hr time-weighted average. In the battery recycling plant, production workers had a mean blood Pb level ± SD of 62.2 ± 12.7 μg/dL, and office workers had a mean blood Pb level ± SD of 43.4 ± 6.6 μg/dL. In the battery manufacturing plant, production workers had a mean blood Pb level ± SD of 59.5 ± 10.1 μg/dL, and office workers had a mean blood Pb level ± SD of 41.6 ± 7.4 μg/dL. All the measured blood Pb levels exceeded 30 μg/dL, which is the maximum blood Pb level recommended by the ACGIH(®). Observations made in these facilities revealed numerous sources of Pb exposure due to inadequacies in engineering controls, work practices, respirator use, and personal hygiene.

  8. Recovery of discarded sulfated lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Karami, Hassan; Asadi, Raziyeh

    The aim of this research is to recover discarded sulfated lead-acid batteries. In this work, the effect of two methods (inverse charge and chemical charge) on the reactivation of sulfated active materials was investigated. At the inverse charge, the battery is deeply discharged and the electrolyte of battery is replaced with a new sulfuric acid solution of 1.28 g cm -3. Then, the battery is inversely charged with constant current method (2 A for the battery with the nominal capacity of 40 Ah) for 24 h. At the final stage, the inversely charged battery is directly charged for 48 h. Through these processes, a discarded battery can recover its capacity to more than 80% of a similar fresh and non-sulfated battery. At the chemical charge method, there are some effective parameters that including ammonium persulfate [(NH 4) 2S 2O 8] concentration, recovery temperature and recovery time. The effect of all parameters was optimized by one at a time method. The sulfated battery is deeply discharged and then, its electrolyte was replaced by a 40% ammonium persulfate solution (as oxidant) at temperature of 50 °C. By adding of oxidant solution, the chemical charging of positive and negative plates was performed for optimum time of 1 h. The chemically charged batteries were charged with constant voltage method (2.66 V for the battery with nominal voltage and nominal capacity of 2 V and 10 Ah, respectively) for 24 h. By performing of these processes, a discarded battery can recovers its capacity to more than 84% of the similar fresh and non-sulfated battery. Discharge and cyclelife behaviors of the recovered batteries were investigated and compared with similar healthy battery. The morphology and structure of plates was studied by scanning electron microscopy (SEM) before and after recovery.

  9. Modeling of the charge acceptance of lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Thele, M.; Schiffer, J.; Karden, E.; Surewaard, E.; Sauer, D. U.

    This paper presents a model for flooded and VRLA batteries that is parameterized by impedance spectroscopy and includes the overcharging effects to allow charge-acceptance simulations (e.g. for regenerative-braking drive-cycle profiles). The full dynamic behavior and the short-term charge/discharge history is taken into account. This is achieved by a detailed modeling of the sulfate crystal growth and modeling of the internal gas recombination cycle. The model is applicable in the full realistic temperature and current range of automotive applications. For model validation, several load profiles (covering the dynamics and the current range appearing in electrically assisted or hybrid cars) are examined and the charge-acceptance limiting effects are elaborately discussed. The validation measurements have been performed for different types of lead-acid batteries (flooded and VRLA). The model is therefore an important tool for the development of automotive power nets, but it also allows to analyze different charging strategies and energy gains which can be achieved during regenerative-braking.

  10. SREB States Maintain Lead in Advanced Placement and International Baccalaureate Programs

    ERIC Educational Resources Information Center

    Collins, Crystal

    2009-01-01

    The Southern Regional Education Board (SREB) states lead the nation in student participation in Advanced Placement (AP) and International Baccalaureate (IB) programs. The region also continued to match the nation in the success rates of high school students on AP exams in 2008. SREB's "Challenge to Lead" Goals for Education recognize the…

  11. Ascorbic acid supplementation does not improve efficacy of meso-dimercaptosuccinic acid treatment in lead-exposed suckling rats.

    PubMed

    Varnai, Veda Marija; Piasek, Martina; Blanusa, Maja; Juresa, Dijana; Sarić, Marija; Kostial, Krista

    2003-10-01

    It was suggested that ascorbic acid as a natural chelating agent can influence lead toxicokinetics and improve chelating properties of dimercaptosuccinic acid (DMSA) in adult rats. In this paper potential benefits of ascorbic acid supplementation, alone or combined with DMSA, in decreasing lead retention in suckling rats were evaluated. Such data in young mammals are not available. L-Ascorbic acid (daily dose 650 mg/kg b.wt.) and/or DMSA (daily dose 91 mg/kg b.wt.) were administered orally to suckling Wistar rats either during ongoing 8-day oral lead exposure (as acetate; daily dose 2 mg lead/kg b.wt.) or after 3-day lead exposure (total dose 12 mg lead/kg b.wt.). Lead concentrations were analysed in the carcass (skeleton), liver, kidneys and brain by atomic absorption spectrometry. By ascorbic acid supplementation lead retention was not reduced under either lead exposure condition. Lead concentration was even increased in the carcass. Treatment with DMSA under both exposure conditions significantly reduced lead in all analysed tissues. Combined treatment with ascorbic acid and DMSA during ongoing lead exposure was substantially less effective than DMSA treatment alone, and did not affect DMSA efficacy when administered after lead exposure. It was concluded that ascorbic acid administered either during or after lead exposure in suckling rats has no beneficial effect on either lead retention or DMSA chelation effectiveness.

  12. Linolenic acid prevents early and advanced glycation end-products (AGEs) modification of albumin.

    PubMed

    Prasanna, Govindarajan; Saraswathi, N T

    2017-02-01

    In this study, we report the protective effects of linolenic acid towards the formation of early (HbA1c) and advanced glycation end-products (AGEs) based on fluorescence, circular dichroism, confocal microscopy and molecular interaction studies. Linolenic acid was found to be a potent inhibitor of AGEs formed by both glucose and fructose. The HbA1c (early glycation product) level was found to be reduced to 7.4% when compared to glycated control (8.4%). Similarly, linolenic acid also inhibited the methylglyoxal mediated AGEs formation. Circular dichroism spectroscopy studies suggested that the protective effect of linolenic acid for the helical structure of albumin. The molecular interaction studies showed that linolenic acid interacts with arginine residues of albumin with high affinity. Results suggested linolenic acid to be a potent antiglycation compound and also it could be a better lead compound for AGE inhibition.

  13. Influence of phosphoric acid on the electrochemistry of lead electrodes in sulfuric acid electrolyte containing antimony

    NASA Astrophysics Data System (ADS)

    Venugopalan, S.

    The influence of phosphoric acid (0 to 40 g 1 -1) on the Pb/PbSO 4 reaction and the kinetics of hydrogen evolution on pure, smooth lead and lead alloy electrodes is studied via galvanostatic polarization in the linear and Tafel domains with and without antimony (0 to 10 mg 1 -1) addition to the H 2SO 4 (3 to 10 M) electrolyte. Phosphoric acid is found to offset significantly the adverse effect of antimony. H 3PO 4 is also found to increase the hydrogen overpotential without affecting the Pb/PbSO 4 reaction. This implies that the open-circuit corrosion of lead and the consequent hydrogen evolution rate on lead are reduced in the presence of H 3PO 4. The beneficial effects of H 3PO 4 additive are found to be optimum at around 20 g 1 -1. Suppression of hydrogen evolution on the negative electrode, a crucial criterion for sealed cell operation, can be achieved using a H 3PO 4 additive.

  14. Anaerobic microbial dissolution of lead and production of organic acids

    DOEpatents

    Francis, A.J.; Dodge, C.; Chendrayan, K.

    1986-02-28

    The present invention relates to a method of solubilizing lead, in the form of lead oxide, found in industrial wastes, before these wastes are dumped into the environment. The lead is solubilized by dissolving the lead oxide in the wastes through contact with an anaerobic bacterial culture containing the bacterium ATCC No. 53464. The solubilized lead can then be removed from the wastes by chemical separation. It could also be removed by extending the contact period with the bacterial culture. As the culture grows, the solubilized lead is removed from the wastes by bioaccumulation by the microorganism or by immobilization by a polymer-like material produced by the microorganism. At this point, the lead is then removed from the wastes when the waste material is separated from the bacterial culture. If desired, the bacterial culture could be digested at this point to yield relatively pure lead for further industrial use.

  15. Recent advances in lactic acid production by microbial fermentation processes.

    PubMed

    Abdel-Rahman, Mohamed Ali; Tashiro, Yukihiro; Sonomoto, Kenji

    2013-11-01

    Fermentative production of optically pure lactic acid has roused interest among researchers in recent years due to its high potential for applications in a wide range of fields. More specifically, the sharp increase in manufacturing of biodegradable polylactic acid (PLA) materials, green alternatives to petroleum-derived plastics, has significantly increased the global interest in lactic acid production. However, higher production costs have hindered the large-scale application of PLA because of the high price of lactic acid. Therefore, reduction of lactic acid production cost through utilization of inexpensive substrates and improvement of lactic acid production and productivity has become an important goal. Various methods have been employed for enhanced lactic acid production, including several bioprocess techniques facilitated by wild-type and/or engineered microbes. In this review, we will discuss lactic acid producers with relation to their fermentation characteristics and metabolism. Inexpensive fermentative substrates, such as dairy products, food and agro-industrial wastes, glycerol, and algal biomass alternatives to costly pure sugars and food crops are introduced. The operational modes and fermentation methods that have been recently reported to improve lactic acid production in terms of concentrations, yields, and productivities are summarized and compared. High cell density fermentation through immobilization and cell-recycling techniques are also addressed. Finally, advances in recovery processes and concluding remarks on the future outlook of lactic acid production are presented.

  16. Distribution and integrated assessment of lead in an abandoned lead-acid battery site in Southwest China before redevelopment.

    PubMed

    Wang, Mei; Zhang, Chao; Zhang, Zhuo; Li, Fasheng; Guo, Guanlin

    2016-06-01

    Lead-acid battery sites have contributed enormous amounts of lead to the environment, significantly affecting its global biogeochemical cycle and leaving the potential risks to human health. An abandoned lead-acid battery site prepared for redevelopment was selected in order to study the distribution of lead in soils, plants, rhizosphere soils and soil solutions. In total, 197 samples from 77 boreholes were collected and analyzed. Single extractions by acetic acid (HOAc) were conducted to assess the bioavailability and speciation of lead in soils for comparison with the parts of the plants that are aboveground. Health risks for future residential development were evaluated by the integrated exposure uptake biokinetic (IEUBK) model. The results indicated that lead concentrations in 83% of the soil samples exceeded the Chinese Environmental Quality Standard for soil (350 mg/kg for Pb) and mainly occurred at depths between 0 and 1.5 m while accumulating at the surface of demolished construction waste and miscellaneous fill. Lead concentrations in soil solutions and HOAc extraction leachates were linked closely to the contents of aboveground Broussonetia papyrifera and Artemisia annua, two main types of local plants that were found at the site. The probability density of lead in blood (PbB) in excess of 10 µg/dL could overtake the 99% mark in the residential scenario. The findings provided a relatively integrated method to illustrate the onsite investigations and assessment for similar sites before remediation and future development from more comprehensive aspects.

  17. Electrodeposited lead-foam grids on copper-foam substrates as positive current collectors for lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Ji, Keju; Xu, Chen; Zhao, Huihui; Dai, Zhendong

    2014-02-01

    Contemporary lead-acid batteries have a high internal resistance and a limited utilization of their positive active materials (PAM). In order to alleviate these problems, lead (alloy) foam-based positive electrodes for lead-acid batteries are prepared by electrodepositing lead on a copper-foam substrate. Using scanning electron microscopy, flame atomic absorption spectrometry, finite element analysis, cyclic voltammetry, and galvanostatic charge/discharge tests, the effect of the lead foam collectors on the electrochemical performance of the positive electrodes is characterized. The thickness of the lead coating has a strong effect on the corrosion-stability of the copper-foam substrate. In addition, the charge/discharge performance of the batteries is greatly improved by the lead-foam collectors. At the 20-2 h discharge rates, the utilization efficiency of the PAM of 40-PPI lead-foam battery is improved by 19-36% from the cast-grid battery. Combined with the finite element analysis, it appears that the 3D connected network structure of the positive lead foam electrode can reduce the surface current density, the polarization resistance, and the ohmic resistance of the battery because of its larger contact area with the active material. As a result, the lead foam battery has a higher utilization efficiency of the PAM.

  18. Advanced Technologies in Sialic Acid and Sialoglycoconjugate Analysis.

    PubMed

    Kitajima, Ken; Varki, Nissi; Sato, Chihiro

    2015-01-01

    Although the structural diversity of sialic acid (Sia) is rapidly expanding, understanding of its biological significance has lagged behind. Advanced technologies to detect and probe diverse structures of Sia are absolutely necessary not only to understand further biological significance but also to pursue medicinal and industrial applications. Here we describe analytical methods for detection of Sia that have recently been developed or improved, with a special focus on 9-O-acetylated N-acetylneuraminic acid (Neu5,9Ac), N-glycolylneuraminic acid (Neu5Gc), deaminoneuraminic acid (Kdn), O-sulfated Sia (SiaS), and di-, oligo-, and polysialic acid (diSia/oligoSia/polySia) in glycoproteins and glycolipids. Much more attention has been paid to these Sia and sialoglycoconjugates during the last decade, in terms of regulation of the immune system, neural development and function, tumorigenesis, and aging.

  19. Lead poisoning among household members exposed to lead-acid battery repair shops in Kingston, Jamaica.

    PubMed

    Matte, T D; Figueroa, J P; Ostrowski, S; Burr, G; Jackson-Hunt, L; Keenlyside, R A; Baker, E L

    1989-12-01

    To investigate the risk of lead poisoning among household members exposed to 'backyard' battery repair shops (BBRS) in Kingston, Jamaica, environmental and blood lead (PbB) were measured at 24 households (112 individuals) with a BBRS worker or located at a BBRS premises and at 18 neighbourhood control households (74 individuals). Elevated PbB (greater than or equal to 25 micrograms per decilitre [micrograms/dl]) was common among subjects of all ages living at BBRS premises, especially among children less than age 12, 43% of whom had PbB greater than 70 micrograms/dl. Potentially hazardous soil and house dust lead levels were also common at BBRS premises, where 84% of yards had soil lead levels above 500 parts per million (geometric mean 3388 parts per million [ppm] at BBRS premises households with a BBRS worker). Geometric mean blood and environmental lead levels were significantly lower at control households, where less than 10% of subjects in all age groups had elevated PbB (maximum 33 micrograms/dl). Sharing a premises with a BBRS was a stronger determinant of household blood lead and environmental contamination than was the presence of a BBRS worker in a household. Blood lead levels were associated with soil and house dust lead levels in all age groups. We conclude that small battery repair shops, which have also been described in other developing countries, create a high lead poisoning risk for nearby residents.

  20. Influences and trends in lead/acid battery demand, lead supply and prices

    NASA Astrophysics Data System (ADS)

    Hawkes, N.

    This study examines: (i) the historical trends and influences in Western World lead demand, paying particular attention to the battery sector; (ii) the historical trends in Western World lead production in both the primary and secondary sectors, highlighting key influences; (iii) the long-term relationship between consumption and both primary and secondary lead production, and (iv) the lead price and stock history, before summarizing the current situation in the lead market. Finally suggestions are given for a few points to watch for in the future. Most of the paper refers separately to 'Western World' and 'Eastern Bloc' countries. The definition of Western World includes all countries except the following: PR China, all CIS republics (the former USSR), Mongolia, North Korea, Cuba, Cambodia, Laos, Vietnam, and the Eastern European countries of Poland, Bulgaria, Romania, Czech and Slovak Republics, Hungary and Albania. These countries are collectively referred to as 'Eastern Bloc'.

  1. Radiogenic lead as coolant, reflector and moderator in advanced fast reactors

    NASA Astrophysics Data System (ADS)

    Kulikov, E. G.

    2017-01-01

    Main purpose of the study is assessing reasonability for recovery, production and application of radiogenic lead as a coolant, neutron moderator and neutron reflector in advanced fast reactors. When performing the study, thermal, physical and neutron-physical properties of natural and radiogenic lead were analyzed. The following results were obtained: 1. Radiogenic lead with high content of isotope 208Pb can be extracted from thorium or mixed thorium-uranium ores because 208Pb is a final product of 232Th natural decay chain. 2. The use of radiogenic lead with high 208Pb content in advanced fast reactors and accelerator-driven systems (ADS) makes it possible to improve significantly their neutron-physical and thermal-hydraulic parameters. 3. The use of radiogenic lead with high 208Pb content in advanced fast reactors as a coolant opens the possibilities for more intense fuel breeding and for application of well-known oxide fuel instead of the promising but not tested enough nitride fuel under the same safety parameters. 4. The use of radiogenic lead with high 208Pb content in ADS as a coolant can upgrade substantially the level of neutron flux in the ADS blanket, which enables effective transmutation of radioactive wastes with low cross-sections of radiative neutron capture.

  2. A psychophysiological comparison of on-sight lead and top rope ascents in advanced rock climbers.

    PubMed

    Fryer, S; Dickson, T; Draper, N; Blackwell, G; Hillier, S

    2013-10-01

    Research suggests that lead climbing is both physiologically and psychologically more stressful than top rope climbing for intermediate performers. This observation may not be true for advanced climbers, who train regularly on lead routes and are accustomed to leader falls. The aim of this study was to compare the psychophysiological stresses of lead and top rope on-sight ascents in advanced rock climbers. Twenty-one climbers (18 men and three women) ascended routes near or at the best of their ability (22 Ewbank). Psychological stress was measured preclimb using the Revised Comparative State Anxiety Inventory (CSAI-2R). Plasma cortisol was sampled at six intervals. The volume of oxygen (VO2 ) and heart rate (Hr) were measured throughout the climbs. No significant differences were found in self-confidence, somatic, or cognitive anxiety between the conditions lead and top rope. No significant differences in plasma cortisol concentration were found between any time points. No significant relationships were found between cortisol and any CSAI-2R measures. No significant differences were found between conditions for VO2 or blood lactate concentration. During the lead climb, Hr was significantly elevated during the last part of the route. Findings suggest that advanced rock climbers do not find lead climbing to be more stressful than top rope climbing during an on-sight ascent.

  3. Integrated li-ion ultracapacitor with lead acid battery for vehicular start-stop

    NASA Astrophysics Data System (ADS)

    Manla, Emad

    Advancements in automobile manufacturing aim at improving the driving experience at every level possible. One improvement aspect is increasing gas efficiency via hybridization, which can be achieved by introducing a feature called start-stop. This feature automatically switches the internal combustion engine off when it idles and switches it back on when it is time to resume driving. This application has been proven to reduce the amount of gas consumption and emission of greenhouse effect gases in the atmosphere. However, the repeated cranking of the engine puts a large amount of stress on the lead acid battery required to perform the cranking, which effectively reduces its life span. This dissertation presents a hybrid energy storage system assembled from a lead acid battery and an ultracapacitor module connected in parallel. The Li-ion ultracapacitor was tested and modeled to predict its behavior when connected in a system requiring pulsed power such as the one proposed. Both test and simulation results show that the proposed hybrid design significantly reduces the cranking loading and stress on the battery. The ultracapacitor module can take the majority of the cranking current, effectively reducing the stress on the battery. The amount of cranking current provided by the ultracapacitor can be easily controlled via controlling the resistance of the cable connected directly between the ultracapacitor module and the car circuitry.

  4. SUNRAYCE 93: Working safely with lead-acid batteries and photovoltaic power systems

    SciTech Connect

    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.

  5. SUNRAYCE 1993: Working safely with lead-acid batteries and photovoltaic power systems

    NASA Astrophysics Data System (ADS)

    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.

  6. Citric acid-assisted phytoextraction of lead: a field experiment.

    PubMed

    Freitas, Eriberto Vagner; Nascimento, Clístenes Williams; Souza, Adailson; Silva, Fernando Bruno

    2013-06-01

    Soil contamination with heavy metals has become a serious environmental problem that requires affordable strategies of remediation. This study was carried out to assess the performance of maize and vetiver in the phytoextraction of Pb from a soil contaminated by battery recycling activities. The species were planted with different spacings between rows (0.80, 0.65 and 0.50m). Citric acid (40mmolkg(-1)) was applied on each experimental plot on the 61st d of cultivation in order to solubilize the Pb and assist the phytoextraction. The results showed that the chelating agent promoted a 14-fold increase in the Pb concentration in maize shoots as compared to the control, which accumulated only 111mgkg(-1) of the metal. The citric acid induced a Pb concentration in vetiver shoots that was 7.2-6.7-fold higher than the control at both the 0.65 and 0.50m plant spacing, respectively. The use of citric acid increased substantially the uptake and translocation of Pb to the shoots, regardless of plant spacing. Citric acid was efficient in solubilizing Pb from the soil and inducing its uptake by both species. Environmentally-friendly and cost effective, commercial citric acid is recommended for assisting Pb-phytoextraction in the studied area. Due to the low natural solubility of Pb and a time frame needed of longer than 150yr to accomplish the clean-up, phytoextraction with no chelate assistance is not recommended for the area.

  7. Lead

    MedlinePlus

    ... Worker, or other abatement discipline Lead in drinking water Lead air pollution Test your child Check and maintain your home Find a Lead-Safe Certified firm Before you renovate Before you buy or rent a home built before 1978 Test your home's drinking water Test for lead in paint, dust or soil ...

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

    PubMed

    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.

  9. Uncovering the Evolution of Lead In-Use Stocks in Lead-Acid Batteries and the Impact on Future Lead Metabolism in China.

    PubMed

    Liu, Wei; Chen, Lujun; Tian, Jinping

    2016-05-17

    This study aims to illustrate the evolution of lead in-use stocks, particularly in lead-acid batteries (LABs), and their impact on future lead metabolism in China. First, we used a bottom-up methodology to study the evolution of lead in-use stocks in China from 2000 to 2014. It was found that the lead in-use stocks increased from 0.91 to 7.75 Mt. The principal driving force of such change is the rapid development of LABs-driven electric vehicles. Then, we proposed three scenarios, low, baseline, and high in-use stocks, to project the lead demand and supply toward 2030. The results show that the LAB demand will decrease as a result of competition and replacement by lithium ion batteries. The lead demand in China will come to a peak around 2018-2020 under the three scenarios, then reduce to 3.7, 4.6, and 5.3 Mt/yr in 2030. Meanwhile, primary lead outputs will follow the increase of zinc production in China. Secondary lead recovered from spent LABs will also increase gradually. The overall unused lead stocks in 2030 will be 49.6, 44.8, and 41.2 Mt under the three scenarios, some 3.5-5.7 times as big as the lead in-use stocks. Thus, a large amount of lead will have to be safely stockpiled or exported in China.

  10. Modeling the crystal distribution of lead-sulfate in lead-acid batteries with 3D spatial resolution

    NASA Astrophysics Data System (ADS)

    Huck, Moritz; Badeda, Julia; Sauer, Dirk Uwe

    2015-04-01

    For the reliability of lead-acid batteries it is important to have an accurate prediction of its response to load profiles. A model for the lead-sulfate growth is presented, which is embedded in a physical-chemical model with 3D spatial resolution is presented which is used for analyzing the different mechanism influencing the cell response. One import factor is the chemical dissolution and precipitation of lead-sulfate, since its dissolution speed limits the charging reaction and the accumulation of indissolvable of lead-sulfate leads to capacity degradation. The cell performance/behavior is not only determined by the amount of the sulfate but also by the radii and distribution of the crystals. The presented model can be used to for an improved understanding of the interaction of the different mechanisms.

  11. Experimental analysis of lead-in-air sources in lead-acid battery manufacture.

    PubMed

    Caplan, K J; Knutson, G W

    1979-07-01

    Plant-scale experimental sampling programs were carried out to determine the contribution to the lead-in-air exposure from (a) fork-truck transport of pasted plates in racks and (b) manual loading and unloading of plates from racks. Fork-truck transport was found not significant under "clean" conditions. Manual loading and unloading was found significant.

  12. Development of Advanced High Lift Leading Edge Technology for Laminar Flow Wings

    NASA Technical Reports Server (NTRS)

    Bright, Michelle M.; Korntheuer, Andrea; Komadina, Steve; Lin, John C.

    2013-01-01

    This paper describes the Advanced High Lift Leading Edge (AHLLE) task performed by Northrop Grumman Systems Corporation, Aerospace Systems (NGAS) for the NASA Subsonic Fixed Wing project in an effort to develop enabling high-lift technology for laminar flow wings. Based on a known laminar cruise airfoil that incorporated an NGAS-developed integrated slot design, this effort involved using Computational Fluid Dynamics (CFD) analysis and quality function deployment (QFD) analysis on several leading edge concepts, and subsequently down-selected to two blown leading-edge concepts for testing. A 7-foot-span AHLLE airfoil model was designed and fabricated at NGAS and then tested at the NGAS 7 x 10 Low Speed Wind Tunnel in Hawthorne, CA. The model configurations tested included: baseline, deflected trailing edge, blown deflected trailing edge, blown leading edge, morphed leading edge, and blown/morphed leading edge. A successful demonstration of high lift leading edge technology was achieved, and the target goals for improved lift were exceeded by 30% with a maximum section lift coefficient (Cl) of 5.2. Maximum incremental section lift coefficients ( Cl) of 3.5 and 3.1 were achieved for a blown drooped (morphed) leading edge concept and a non-drooped leading edge blowing concept, respectively. The most effective AHLLE design yielded an estimated 94% lift improvement over the conventional high lift Krueger flap configurations while providing laminar flow capability on the cruise configuration.

  13. The performance of Ebonex ® electrodes in bipolar lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Ellis, Keith; Hill, Andrew; Hill, John; Loyns, Andrew; Partington, Tom

    Recent work by Atraverda on the production of an Ebonex ® material that can be cheaply formulated and manufactured to form bipolar substrate plates for bipolar lead-acid batteries is described. In addition, data obtained by Atraverda from laboratory lead-acid batteries is presented indicating that weight savings of around 40% for a bipolar 36 V design (20 Ah capacity, 5 h rate, 9 kW) are potentially achievable in comparison to more conventional designs containing monopolar lead grids. Results indicate that their use as bipolar substrate materials will provide light-weight, long-lasting lead-acid batteries suitable for automotive, standby and power tool applications.

  14. Advanced leading edge thermal-structure concept. Direct bond reusable surface insulation to a composite structure

    NASA Technical Reports Server (NTRS)

    Riccitiello, S. R.; Figueroa, H.; Coe, C. F.; Kuo, C. P.

    1984-01-01

    An advanced leading-edge concept was analyzed using the space shuttle leading edge system as a reference model. The comparison indicates that a direct-bond system utilizing a high temperature (2700 F) fibrous refractory composite insulation tile bonded to a high temperature (PI/graphite) composite structure can result in a weight savings of up to 800 lb. The concern that tile damage or loss during ascent would result in adverse entry aerodynamics if a leading edge tile system were used is addressed. It was found from experiment that missing tiles (as many as 22) on the leading edge would not significantly affect the basic force-and-moment aerodynamic coefficients. Additionally, this concept affords a degree of redundancy to a thermal protection system in that the base structure (being a composite material) ablates and neither melts nor burns through when subjected to entry heating in the event tiles are actually lost or damaged during ascent.

  15. Temporal and spatial characteristics of lead emissions from the lead-acid battery manufacturing industry in China.

    PubMed

    Liu, Wei; Tian, Jinping; Chen, Lujun; Guo, Yang

    2017-01-01

    An inventory of lead emissions was established for the lead-acid battery (LAB) manufacturing industry in China from 2000 to 2014. The lead emissions from the LAB manufacturing industry increased from 133 t in 2000 to a peak at 281 t in 2010 with the rapid development of LAB industry. Since 2011, a mandatory national clean action on LAB industry and a series of retrofitting measures have been implemented in China. As a result, more than 80% of small and low-efficient LAB manufacturers were closed, and technical-environmental performance of the industry has been improved significantly. Thus the lead emissions from the industry declined to 113 t in 2014. Geographically, lead emissions were attributed to several provinces with intensive LAB manufacturers, including Zhejiang, Guangdong, Jiangsu, Shandong, and Hebei Province. Spatial transfer of the LAB manufacturing industry from developed areas to developing areas in China was manifest due to strict environmental regulation, posing potential environmental risks to the areas undertaking the industry transfer. In light of the effectiveness of the national clean action, the LAB manufacturing industry will reduce lead emissions further by implementing the entry criteria strictly, adopting policy of total lead emissions control, and establishing a long-term regulatory mechanism for LAB manufacturers. The local authorities in some developing areas should improve abilities of environmental supervision and environmental risk prevention to deal with the spillover of lead emissions.

  16. Acid-fast intranuclear inclusion bodies in the kidneys of mallards fed lead shot

    USGS Publications Warehouse

    Locke, L.N.; Bagley, George E.; Irby, H.D.

    1966-01-01

    Acid-fast intranuclear inclusion bodies were found in the cells of the proximal convoluted tubules of the kidneys of mallards fed one, two, three or eight number 6 lead shot and maintained on cracked or whole corn and on grain-duck pellet diets. No acid-fast inclusion bodies were found in mallards fed one or three lead shot but maintained on a duck pellet ration. Dietary factors may be responsible for the failure of mallards fed a duck pellet ration to develop lead Inclusion bodies when treated with one or three lead shot. The authors suggest these inclusion bodies can be used as presumptive evidence for lead intoxication in mallards.

  17. Improved grid materials for valve regulated lead acid batteries

    SciTech Connect

    Prengaman, R.D.

    1997-12-01

    During the last several years, research into lead alloys used as grid materials for VRLA batteries has led to a much better understanding of the roles of chemical composition and mechanical properties on the performance of the battery. VRLA batteries have suffered from premature capacity losses. It was believed that the loss was due to the absence of antimony in the battery grids. Recent work has indicated the beneficial effects of high tin contents on enhancing the conductivity of the grid-active material interface, increasing the mechanical properties, and reducing the corrosion rates of Pb-Ca-Sn alloys used in VRLA batteries. Additions of silver and controlled deformation processes enhance resistance to growth at elevated operating temperatures. The paper discusses how modification of composition and processing parameters can produce more stable, corrosion resistant, grid materials for VRLA batteries.

  18. Evaluation of preventive and control measures for lead exposure in a South African lead-acid battery recycling smelter.

    PubMed

    Dyosi, Sindiswa

    2007-10-01

    In South Africa, new lead regulations released in February 2002 served as motivation for a cross-sectional study investigating the effectiveness of preventive and control measures implemented in a lead smelter that recycles lead-acid batteries. Twenty-two workers were observed and interviewed. Structured questionnaires were used to gather workers' personal information, perception about their work environment, health risks, and work practices. Retrospective data from air monitoring and medical surveillance programs were obtained from the plant's records. The smelter implemented a number of control measures for lead exposure, including engineering controls, administrative controls, and, as a last resort, personal protective equipment. Engineering controls were rated the best control measure and included local exhaust ventilation systems and wet methods. Positive pressure systems were used in the offices and laboratory. The local exhaust ventilation system was rated the best engineering control measure. Although control measures were used, areas such as smelting and refinery had average lead in air levels above 0.15 mg/m(3), the occupational exposure limit for lead. This was a concern especially with regard to the smelting area because those workers had the second highest mean blood lead levels; workers in the battery breaking area had the highest. Regular use of personal protective equipment by some workers in the "lead exposure zones" was not observed. Although the mean blood lead levels had been below 40 micro g/dL for more than 90% of the workers since 2001, more than 70% of workers reported concerns about their health while working in the smelter. Even though control measures were implemented, they were not adequate because in some areas lead in air exceeded the occupational exposure limit. Therefore, improvement of existing measures and regular monitoring of personal protective equipment use were included in the recommendations given to the smelter.

  19. A novel ultrafine leady oxide prepared from spent lead pastes for application as cathode of lead acid battery

    NASA Astrophysics Data System (ADS)

    Yang, Danni; Liu, Jianwen; Wang, Qin; Yuan, Xiqing; Zhu, Xinfeng; Li, Lei; Zhang, Wei; Hu, Yuchen; Sun, Xiaojuan; Kumar, R. Vasant; Yang, Jiakuan

    2014-07-01

    A novel ultrafine leady oxide has been prepared from a combustion-calcination process of lead citrate precursor (Pb3(C6H5O7)2·3H2O), by hydrometallurgical leaching of spent lead pastes firstly. The leady oxides are used to assemble lead acid battery which are subjected to cyclic voltammetry (CV) and battery testing. Various key properties of the new oxides, such as morphology, crystalline phases, degree of oxidation, apparent density and water and acid absorption value have been characterized by chemical analysis, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results show that leady oxides synthesized at different calcination temperatures mainly comprise β-PbO, α-PbO and Pb. Unlike traditional leady oxide, the new oxide product prepared at 375 °C has a rod-like morphology with greater porous structure, and appears smaller density, lower value of acid absorption and larger propensity for water absorption. In battery testing, the 20 h rate and 1C rate discharge time have exceeded 26 h and 40 min, respectively. Results reveal that the leady oxide prepared at 375 °C exhibits excellent electrochemical performance and initial capacity as positive active material. While leady oxide obtained at 450 °C presents a relatively improved cycle life. Further work is to optimize the battery manufacturing process for better cycle performance.

  20. Conversion of tribasic lead sulfate to lead dioxide in lead/acid battery plates. 1: Relationship between the phase compositions of plates in the cured and formed states

    NASA Astrophysics Data System (ADS)

    Zerroual, L.; Chelali, N.; Tedjar, F.; Guitton, J.

    1994-10-01

    The influence of the initial amount of H2SO4 added to lead powder on the phase compositions of plates in the cured and formed states has been studied. IR spectra, x-ray diffraction, scanning electron microscope observations, and wet-chemical analysis are used as techniques of investigation. It was found that the phase composition of the paste depends on the H2SO4:oxidized lead powder ratio. In addition, it is found that alpha- and beta-PbO2 are formed in the lead/acid battery positive plate from 3PbO center-dot PbSO4 center-dot H2O. The amounts of these two compounds were strongly affected when varying the quantity of H2SO4 with respect to the lead powder.

  1. Lead

    MedlinePlus

    ... ATSDR Board of Scientific Counselors Lead in the environment: Agency for Toxic Substances and Disease Registry (ATSDR) Federal partner agencies: Department of Housing and Urban Development (HUD) and U.S. Environmental Protection Agency (EPA) Data, ...

  2. Investigation of lead dendrite growth in the formation of valve-regulated lead-acid batteries for electric bicycle applications

    NASA Astrophysics Data System (ADS)

    Zeng, Yanzhen; Hu, Jingcheng; Ye, Wenmei; Zhao, Wenchao; Zhou, Gang; Guo, Yonglang

    2015-07-01

    The battery temperature, H2SO4 distribution, Pb2+ ion concentration and composition of the plates during the plate soaking of the 12 V 12 Ah valve-regulated lead-acid (VRLA) battery are studied. A simulated cell composed by two pure Pb plates and the absorptive glass mat (AGM) separator is used to investigate the growth of the lead dendrite in the separator, which is verified by analyzing the faulty batteries after the formation and the failure batteries after the usage. It is found that the H2SO4 is exhausted very quickly after filling and the separator near the plates can become neutral during soaking. Low acidity, high temperature and small PbSO4 particle size will increase the Pb2+ ion concentration. Higher Pb2+ ion concentration makes more PbSO4 tend to deposit on the coarse glass fibers, develop along them and even enwrap the entire fiber. And the fine PbSO4 crystals are continually transformed into large PbSO4 crystals via dissolution-deposition. In the subsequent charge, these PbSO4 crystals will be reduced to the club-shaped lead dendrites and may lead to short circuit of the battery.

  3. The development of a new sealed bipolar lead-acid battery

    NASA Technical Reports Server (NTRS)

    Attia, A. I.; Rowlette, J. J.

    1988-01-01

    New light weight composite bipolar plates which can withstand the corrosive environment of the lead acid battery have made possible the construction of a sealed bipolar lead acid battery that promises to achieve very high specific power levels and substantially higher energy densities than conventional lead acid batteries. Performance projections based on preliminary experimental results show that the peak specific power of the battery can be as high as 90 kW/kg, and that a specific power of 5 kW/kg can be sustained over several thousand pulses.

  4. Influence of the degree of exposure to lead on relations between alcohol consumption and the biological indices of lead exposure: epidemiological study in a lead acid battery factory.

    PubMed Central

    Cezard, C; Demarquilly, C; Boniface, M; Haguenoer, J M

    1992-01-01

    Alcohol has been shown to interact with lead to influence haem biosynthesis. The aim of this study was to define the dependence of this interaction on the degree of exposure to lead. Exposure to alcohol was estimated by measurement of alcohol concentrations in a sample of urine collected during the morning (AlcUM) (0.82 (SD 4.36) mmol/l) and in a sample collected during the afternoon (AlcUA) (1.15 (SD 3.49) mmol/l). The biological monitoring of exposure to lead included measurements of blood lead (Pb-B) (1.82 (SD 0.72) mumol/l), urinary delta-aminolaevulinic acid (ALAU) (35.33 (SD 28.00) mumol/l; d = 1.015), and erythrocyte zinc-protoporphyrin (ZPP) (112.90 (SD 83.71) nmol/mmol Hb) concentrations. The study of the influence of the degree of occupational exposure to lead on relations between alcohol consumption and effects of the exposure to lead led to the consideration of two different groups--namely, mildly and strongly exposed subjects. In the first group, individual biological susceptibility seemed to play a preponderant part. In the second, the pool of lead present in the body seemed to be sufficiently important to mask the effects of individual susceptibility. PMID:1390270

  5. Recovery of lead from smelting fly ash of waste lead-acid battery by leaching and electrowinning.

    PubMed

    Chen, Chuh-Shun; Shih, Yu-Jen; Huang, Yao-Hui

    2016-06-01

    Fly ash that was enriched with lead (Pb), formed as an intermediate in waste lead-acid battery (WLAB) smelting, was recycled by the hydro-electrometallurgy. Characterization of fly ash thereof indicated that the Pb was in the forms of PbSO4 (anglesite) and Pb2OSO4 (lanarkite). Nitric acid and sodium hydroxide were firstly used to study the leaching of the fly ash sample, which was affected by leachant dosage and solid-to-liquid ratio (S/L). At an S/L of 60gL(-1), the leachability of Pb was 43% and 67% in 2M acidic and basic solutions, respectively, based on an average 70wt% of Pb in the original fly ash. Anglesite was completely soluble in NaOH and lanarkite was mildly soluble in HNO3. Pb was recovered from the pregnant leach solution within an electrolytic cell constructed with graphite or RuO2/IrO2-coated titanium (Ti-DSA) anodes and a stainless steel cathode. Properties of anodes deposited with lead dioxides were analyzed by cyclic voltammetry. The optimized parameters of electrowinning were 2M NaOH leachant, a current density of 0.75Adm(-2) and an electrolytic process duration of 120min, which yielded a Pb removal of higher than 99% and a specific energy consumption of 0.57Whg(-1). This process constitutes an eco-friendly and economic alternative to the presently utilized secondary pyrometallurgy for treating lead-containing fly ash.

  6. Delta-aminolevulinic acid dehydratase: Inhibition in ducks dosed with lead shot

    USGS Publications Warehouse

    Finley, M.T.; Dieter, M.P.; Locke, L.N.

    1976-01-01

    Lead concentration in blood and erythrocyte delta-aminolevulinic acid dehydratase (ALAD) activity was measured in mallard ducks dosed with one all-lead shot or one lead-iron combination shot. For 2 weeks after dosage, lead in blood of ducks given an all-lead shot was fourfold higher than in those dosed with lead-iron shot. At 3 and 4 weeks, the differences in lead residues were directly proportional to lead content of the shots. ALAD activities measured at these intervals were inversely correlated (P < 0.01) with the concentration of lead in the blood, suggesting that biochemical responses to the two types of shot were dependent upon the quantity of lead present.

  7. Lead Acid Battery Reporting Under EPCRA Sections 311 and 312 - REVISED

    EPA Pesticide Factsheets

    This memorandum provides guidance for the calculation of reporting thresholds under Emergency Planning and Community Right-to-Know for nonconsumer type lead acid batteries, such as those used in telephone switching stations or in forklifts.

  8. Electrodeposition of lustrous tin-lead alloys in acidic electrolytes with organic additives

    SciTech Connect

    Selivanova, G.A.; Maksimenko, S.A.; Tyutina, K.M.

    1994-09-01

    Galvanic coatings based on tin-lead alloys are mainly used in radio-engineering and electronic industries to prepare certain products, including printed-circuit boards, for soldering. To improve ecological safety of the proces, the authors studied a new electrolyte for depositing a tin-lead alloy based on nontoxic and abundant perchloric acid, as well as electrolytes based on mono- and trichloroacetic acids.

  9. Arctic sea ice leads from advanced very high resolution radiometer images

    NASA Technical Reports Server (NTRS)

    Lindsay, R. W.; Rothrock, D. A.

    1995-01-01

    A large number of advanced very high resolution radiometer (AVHRR) images from throughout 1989 are analyzed to determine lead characteristics. The units of analysis are square 200-km cells, and there are 270 such cells in the data set. Clouds are masked manually. Leads determine from images of the potential open water delta, a scaled version of the surface temperature or albedo that weights thin ice by its thermal or brightness impact. The lead fraction is determined as the mean delta, the monthly mean lead fraction ranges from 0.02 in winter to 0.06 in summer in the central Arctic and is near 0.08 in the winter in the peripheral seas. A method of accounting for lead width sampling errors due to the finite sample areas is introduced. In the central Arctic the observed mean lead width for a threshold of delta = 0.1 ranges from 2 or 3 km (near the resolution of the instrument) in the winter to 6 km in the summer. In the peripheral seas it is about 5 km in the winter. Width distributions are often more heavily weighted in the tail than exponential distributions and are well approximated by a power law. The along-track, number density power law N = aw(exp -6) has a mean exponent of b = 1.60 (standard deviation 0.18) and shows some seasonal variability. Mean floe widths in the central Arctic are 40 to 50 km in the winter, dropping to about 10 km in the summer. For floes the power law has a mean exponent of 0.93 and exhibits a clearer annual cycle. Lead orientation is determined with a method based on the direction of maximum extent.

  10. Method of making a sealed lead-acid battery with a gel electrolyte and sealed lead-acid storage battery made according to this method

    SciTech Connect

    Chreitzberg, A.M.; Chiacchio, F.J.

    1987-08-18

    A method is described of making a sealed lead-acid storage battery having a plurality of electrodes and a gel electrolyte consisting substantially of sulfuric acid and a gelling agent, comprising the steps of: (a) activating a dry unformed battery by filling the battery with sulfuric acid, (b) maintaining the battery on open circuit or a period of time sufficient to chemically bond sulphuric acid as sulfate to the electrodes and lower the specific gravity of the acid to the desired gelling value, (c) dumping the free acid from the battery, (d) adding a solution of gelling agent and sulfuric acid to fill the battery to the normal formation level, (e) formation charging the battery by applying a constant charge current of 5-16 A/100 Ah for an input of 200-300 Ah/lb. positive active material whereby gelling of the electrolyte is effected, (f) when formation is complete, removing excess liquid, if any, to top of electrodes, and (g) sealing the battery with a pressure relief valve.

  11. A systematic approach to diverse, lead-like scaffolds from α,α-disubstituted amino acids.

    PubMed

    Foley, Daniel J; Doveston, Richard G; Churcher, Ian; Nelson, Adam; Marsden, Stephen P

    2015-06-30

    A powerful strategy for the efficient lead-oriented synthesis of novel molecular scaffolds is demonstrated. Twenty two scaffolds were prepared from just four α-amino acid-derived building blocks and a toolkit of six connective reactions. Importantly, each individual scaffold has the ability to specifically target lead-like chemical space.

  12. Influence of residual elements in lead on oxygen- and hydrogen-gassing rates of lead-acid batteries

    NASA Astrophysics Data System (ADS)

    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.

  13. The use of nanometer tetrabasic lead sulfate as positive active material additive for valve regulated lead-acid battery

    NASA Astrophysics Data System (ADS)

    Lang, Xiaoshi; Wang, Dianlong; Hu, Chiyu; Tang, Shenzhi; Zhu, Junsheng; Guo, Chenfeng

    2014-12-01

    Conventional tetrabasic lead sulfate used as positive active material additive shows the results of the low effective lead dioxide conversion rate due to the large grain size and crossed the crystal structure. In this paper, we study on a type of nanometer tetrabasic lead sulfate. Through the XRD and SEM test and Material Studio software calculation, the purity of tetrabasic lead sulfate is very high, the grain size of the nanometer 4BS is almost unanimous, and can be controlled below 200 nm. When charged and discharged in 1.75 V-2.42 V with the current density of 40 mA g-1, 80 mA g-1 and 160 mA g-1, the effective lead dioxide conversion rate of nanometer 4BS after formation can achieve to 83.48%, 71.42%, and 66.96%. Subsequently, the nanometer 4BS as additive is added to positive paste of lead-acid battery. When the batteries are tested galvanostatically between 1.75 V and 2.42 V at 0.25 C charge and 0.5 C discharge rates at room temperature. The ratio of adding nanometer 4BS is 0%, 1% and 4% and the initial discharge specific capacities are 60 mAh g-1, 65 mAh g-1 and 68 mAh g-1. After 80 cycles, the initial discharge capacity of positive active material with 1% nanometer 4BS decreased less than 10%, while adding 4% nanometer 4BS, the initial discharge capacity doesn't decrease obviously.

  14. Qualitative critical incident study of patients’ experiences leading to emergency hospital admission with advanced respiratory illness

    PubMed Central

    Karasouli, Eleni; Munday, Daniel; Bailey, Cara; Staniszewska, Sophie; Hewison, Alistair; Griffiths, Frances

    2016-01-01

    Objectives The high volume of emergency admissions to hospital is a challenge for health systems internationally. Patients with lung cancer and chronic obstructive pulmonary disease (COPD) are frequently admitted to hospital as emergency cases. While the frequency of emergency admission has been investigated, few studies report patient experiences, particularly in relation to the decision-making process prior to emergency admission. We sought to explore patient and carer experiences and those of their healthcare professionals in the period leading up to emergency admission to hospital. Setting 3 UK hospitals located in different urban and rural settings. Design Qualitative critical incident study. Participants 24 patients with advanced lung cancer and 15 with advanced COPD admitted to hospital as emergencies, 20 of their carers and 50 of the health professionals involved in the patients’ care. Results The analysis of patient, carer and professionals’ interviews revealed a detailed picture of the complex processes involved leading to emergency admission to hospital. 3 phases were apparent in this period: self-management of deteriorating symptoms, negotiated decision-making and letting go. These were dynamic processes, characterised by an often rapidly changing clinical condition, uncertainty and anxiety. Patients considered their options drawing on experience, current and earlier advice. Patients tried to avoid admission, reluctantly accepting it, albeit often with a sense of relief, as anxiety increased with worsening symptoms. Conclusions Patients with advanced respiratory illness, and their carers, try to avoid emergency admission, and use logical and complex decision-making before reluctantly accepting it. Clinicians and policy-makers need to understand this complex process when considering how to reduce emergency hospital admissions rather than focusing on identifying and labelling admissions as ‘inappropriate’. PMID:26916687

  15. Changing corporate culture within the European lead/acid battery industry

    NASA Astrophysics Data System (ADS)

    Mayer, M. G.

    1994-02-01

    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.

  16. Design & fabrication of two seated aircraft with an advanced rotating leading edge wing

    NASA Astrophysics Data System (ADS)

    Al Ahmari, Saeed Abdullah Saeed

    The title of this thesis is "Design & Fabrication of two Seated Aircraft with an Advanced Rotating Leading Edge Wing", this gives almost a good description of the work has been done. In this research, the moving surface boundary-layer control (MSBC) concept was investigated and implemented. An experimental model was constructed and tested in wind tunnel to determine the aerodynamic characteristics using the leading edge moving surface of modified semi-symmetric airfoil NACA1214. The moving surface is provided by a high speed rotating cylinder, which replaces the leading edge of the airfoil. The angle of attack, the cylinder surfaces velocity ratio Uc/U, and the flap deflection angle effects on the lift and drag coefficients and the stall angle of attack were investigated. This new technology was applied to a 2-seat light-sport aircraft that is designed and built in the Aerospace Engineering Department at KFUPM. The project team is led by the aerospace department chairman Dr. Ahmed Z. AL-Garni and Dr. Wael G. Abdelrahman and includes graduate and under graduate student. The wing was modified to include a rotating cylinder along the leading edge of the flap portion. This produced very promising results such as the increase of the maximum lift coefficient at Uc/U=3 by 82% when flaps up and 111% when flaps down at 40° and stall was delayed by 8degrees in both cases. The laboratory results also showed that the effective range of the leading-edge rotating cylinder is at low angles of attack which reduce the need for higher angles of attack for STOL aircraft.

  17. 78 FR 15753 - Maintenance, Testing, and Replacement of Vented Lead-Acid Storage Batteries for Nuclear Power Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-12

    ... COMMISSION Maintenance, Testing, and Replacement of Vented Lead-Acid Storage Batteries for Nuclear Power..., DG-1269 ``Maintenance, Testing, and Replacement of Vented Lead-Acid Storage Batteries for Nuclear... lead-acid storage batteries in nuclear power plants. DATES: Submit comments by May 13, 2013....

  18. 78 FR 58574 - Maintenance, Testing, and Replacement of Vented Lead-Acid Storage Batteries for Nuclear Power Plants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-24

    ... COMMISSION Maintenance, Testing, and Replacement of Vented Lead-Acid Storage Batteries for Nuclear Power..., Testing, and Replacement of Vented Lead-Acid Storage Batteries for Nuclear Power Plants.'' The guide... with regard to the maintenance, testing, and replacement of vented lead-acid storage batteries...

  19. 75 FR 36034 - Advance Notice of Proposed Rulemaking on Lead Emissions From Piston-Engine Aircraft Using Leaded...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-24

    ...: EPA is announcing a 60-day extension of the public comment period for the Advance Notice of Proposed... Register on April 28, 2010. The public comment period was to end on June 28, 2010 (60 days after its publication in the Federal Register). This document extends the comment period an additional 60 days...

  20. Recent advances in nitrogen-fixing acetic acid bacteria.

    PubMed

    Pedraza, Raúl O

    2008-06-30

    Nitrogen is an essential plant nutrient, widely applied as N-fertilizer to improve yield of agriculturally important crops. An interesting alternative to avoid or reduce the use of N-fertilizers could be the exploitation of plant growth-promoting bacteria (PGPB), capable of enhancing growth and yield of many plant species, several of agronomic and ecological significance. PGPB belong to diverse genera, including Azospirillum, Azotobacter, Herbaspirillum, Bacillus, Burkholderia, Pseudomonas, Rhizobium, and Gluconacetobacter, among others. They are capable of promoting plant growth through different mechanisms including (in some cases), the biological nitrogen fixation (BNF), the enzymatic reduction of the atmospheric dinitrogen (N(2)) to ammonia, catalyzed by nitrogenase. Aerobic bacteria able to oxidize ethanol to acetic acid in neutral or acid media are candidates of belonging to the family Acetobacteraceae. At present, this family has been divided into ten genera: Acetobacter, Gluconacetobacter, Gluconobacter, Acidomonas, Asaia, Kozakia, Saccharibacter, Swaminathania, Neoasaia, and Granulibacter. Among them, only three genera include N(2)-fixing species: Gluconacetobacter, Swaminathania and Acetobacter. The first N(2)-fixing acetic acid bacterium (AAB) was described in Brazil. It was found inside tissues of the sugarcane plant, and first named as Acetobacter diazotrophicus, but then renamed as Gluconacetobacter diazotrophicus. Later, two new species within the genus Gluconacetobacter, associated to coffee plants, were described in Mexico: G. johannae and G. azotocaptans. A salt-tolerant bacterium named Swaminathania salitolerans was found associated to wild rice plants. Recently, N(2)-fixing Acetobacter peroxydans and Acetobacter nitrogenifigens, associated with rice plants and Kombucha tea, respectively, were described in India. In this paper, recent advances involving nitrogen-fixing AAB are presented. Their natural habitats, physiological and genetic aspects

  1. Vibration test methods and their experimental research on the performance of the lead-acid battery

    NASA Astrophysics Data System (ADS)

    He, Baoxiang; Wang, Hua; He, Xie

    2014-12-01

    As we know, Lead-acid battery is difficult to balance many factors such as the accuracy and the on-line testing requirement. The detecting system, as stated in this article, is based on the vibration test procedure, dynamically following the electrochemical process of the Lead-acid Battery, and collects the real-time state parameters for calculation, analysis and judgment. It also quantizes precisely the degradation and chargeability of the battery and therefore self-adapts to the ideal target values. During the test, it has not charged and discharged large current to the lead-acid battery, it only plus a smaller and shorter time of impulse voltage signal on both ends of lead-acid battery, so the battery measured is damage free, and the system energy consumption is small; Using the load compensation technology, it has solved the influence of load on the test results. What's more, the load characteristics are improved at the same time, it realized the online detection. The vibration detection is based on the adaptive fuzzy inference model which has taken various factors into account, concerning the choices of input aspects which may influence the output value. It realized a number of Lead-acid Battery voltage self-adaption and accomplished a variety of high-precise tests.

  2. Dynamics of three organic acids (malic, acetic and succinic acid) in sunflower exposed to cadmium and lead.

    PubMed

    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.

  3. The evolving role of health educators in advancing patient safety: forging partnerships and leading change.

    PubMed

    Mercurio, Annette

    2007-04-01

    At least 1.5 million preventable injuries because of adverse drug events occur in the United States each year, according to an Institute of Medicine report. IOM and other organizations at the forefront of health care improvement emphasize that stronger partnerships between patients, their families, and health care providers are necessary to make health care safer. Health educators possess a skill set and an ethical framework that effectively equip them to advance patient and family-centered care and contribute in other significant ways to a safer health care system. Health educators in clinical settings are playing varied and significant roles in advancing patient safety. They are removing barriers to clear communication and forging partnerships between patients, their families, and staff. Health educators are leading patient safety culture change within their institutions and contributing to the shift from provider-centric to patient-centric systems. To expand their impact in improving patient safety, health educators in clinical settings are participating in public awareness campaigns. In seeking to enhance patient safety, health educators face a number of challenges. To successfully manage those, health educators must expand their knowledge, broaden connections, and engage patients and families in meaningful ways.

  4. Immunogenetic mechanisms leading to thyroid autoimmunity: recent advances in identifying susceptibility genes and regions.

    PubMed

    Brand, Oliver J; Gough, Stephen C L

    2011-12-01

    The autoimmune thyroid diseases (AITD) include Graves' disease (GD) and Hashimoto's thyroiditis (HT), which are characterised by a breakdown in immune tolerance to thyroid antigens. Unravelling the genetic architecture of AITD is vital to better understanding of AITD pathogenesis, required to advance therapeutic options in both disease management and prevention. The early whole-genome linkage and candidate gene association studies provided the first evidence that the HLA region and CTLA-4 represented AITD risk loci. Recent improvements in; high throughput genotyping technologies, collection of larger disease cohorts and cataloguing of genome-scale variation have facilitated genome-wide association studies and more thorough screening of candidate gene regions. This has allowed identification of many novel AITD risk genes and more detailed association mapping. The growing number of confirmed AITD susceptibility loci, implicates a number of putative disease mechanisms most of which are tightly linked with aspects of immune system function. The unprecedented advances in genetic study will allow future studies to identify further novel disease risk genes and to identify aetiological variants within specific gene regions, which will undoubtedly lead to a better understanding of AITD patho-physiology.

  5. LEAD IMMOBILIZATION TECHNOLOGY UTILIZING POTASSIUM DEHYDROGEN PHOSPHATE AND ORGANIC ACID IN AN ACTUAL SHOOTING RANGE LEAD-CONTAMINATED SOIL

    NASA Astrophysics Data System (ADS)

    Yoshida, Takatoshi; Katoh, Masahiko; Sato, Takeshi

    This paper addressed potassium dehydrogen phosphate (KP) and acetic acid (OAc) amendments of neutral pH soil sampled from the lead contaminated soil in a shooting range to promote immobilization by modification of Pb speciation in solid and liquid phases. This study evaluated the amount of antimony leachability in the so il. The single KP application increased Pb and Sb leachabilitie s due to soil pH increase, wheres combined KP and OAc amendments decreased them in compar ison with the control. Sequential extraction analysis reveal ed that Pb residual fraction in KP amended soil increased to 72% than that in the control (5%). Th e residual fraction (82%) in KP an d OAc amended soil was higher than the single application of KP. This st udy indicated that combined appli catons of KP and OAc promoted Pb immobilization and suppressed Pb leachabilities.

  6. Chemical synthesis of lactic acid from cellulose catalysed by lead(II) ions in water.

    PubMed

    Wang, Yanliang; Deng, Weiping; Wang, Binju; Zhang, Qinghong; Wan, Xiaoyue; Tang, Zhenchen; Wang, Ye; Zhu, Chun; Cao, Zexing; Wang, Guichang; Wan, Huilin

    2013-01-01

    The direct transformation of cellulose, which is the main component of lignocellulosic biomass, into building-block chemicals is the key to establishing biomass-based sustainable chemical processes. Only limited successes have been achieved for such transformations under mild conditions. Here we report the simple and efficient chemocatalytic conversion of cellulose in water in the presence of dilute lead(II) ions, into lactic acid, which is a high-value chemical used for the production of fine chemicals and biodegradable plastics. The lactic acid yield from microcrystalline cellulose and several lignocellulose-based raw biomasses is >60% at 463 K. Both theoretical and experimental studies suggest that lead(II) in combination with water catalyses a series of cascading steps for lactic acid formation, including the isomerization of glucose formed via the hydrolysis of cellulose into fructose, the selective cleavage of the C3-C4 bond of fructose to trioses and the selective conversion of trioses into lactic acid.

  7. Comparison of blood lead and blood and plasma δ-aminolevulinic acid concentrations as biomarkers for lead poisoning in cattle.

    PubMed

    Kang, Hwan Goo; Bischoff, Karyn; Ebel, Joseph G; Cha, Sang Ho; McCardle, James; Choi, Cheong Up

    2010-11-01

    Lead (Pb) concentrations in whole blood and δ-aminolevulinic acid (ALA) concentrations in plasma and whole blood from 37 cattle with suspected Pb exposure were determined in order to investigate the usefulness of ALA as a biological indicator for Pb poisoning in cattle. Cows were divided into 4 groups based on blood Pb, as follows: <30 ppb (group 1), 30-100 ppb (group 2), 100-300 ppb (group 3), and >300 ppb (group 4). The derivatization reaction for ALA was improved by a greater than 2-fold measure in whole blood and by a 10-fold measure in plasma by adding 75 and 50 µl of 0.1 N HCl, respectively. Blood Pb concentrations ranged from <25 ppb to 1,006 ppb (185.5 ± 254.9 ppb), with 17 samples containing >50 ppb Pb. Delta-aminolevulinic acid concentrations in whole blood and plasma ranged from <62.7 ppb to 96.9 ppb (77.4 ± 8.4 ppb) and from <5.0 ppb to 24.0 ppb (4.6 ± 3.8 ppb), respectively. Whole blood ALA did not correlate with blood lead concentrations in any group. Increase in plasma ALA concentration was dependent on blood Pb concentration. There was no correlation between blood Pb concentration and plasma ALA concentration in group 2 (n  =  4), but correlation coefficients were 0.736 in group 3 and 0.807 in group 4, respectively. The correlation coefficient was increased to 0.851 when groups 3 and 4 were combined. Based on these observations, in cattle, plasma ALA is a more reliable biological biomarker for Pb exposure than is blood ALA.

  8. Single-Wall Carbon Nanotube Doping in Lead-Acid Batteries: A New Horizon.

    PubMed

    Banerjee, Anjan; Ziv, Baruch; Shilina, Yuliya; Levi, Elena; Luski, Shalom; Aurbach, Doron

    2017-02-01

    The addition of single-wall carbon nanotubes (SWCNT) to lead-acid battery electrodes is the most efficient suppresser of uncontrolled sulfation processes. Due to the cost of SWCNT, we studied the optimization loading of SWCNT in lead-acid battery electrodes. We optimized the SWCNT loading concentrations in both the positive and negative plates, separately. Loadings of 0.01% and 0.001% in the positive and negative active masses were studied, respectively. Two volts of lead-acid laboratory cells with sulfuric acid, containing silica gel-type electrolytes, were cycled in a 25% and 50% depth-of-discharge (DOD) cycling with a charging rate of C and 2C, respectively, and discharge rates of C/2 and C, respectively. All tests successfully demonstrated an excellent service life up to about 1700 and 1400 cycles for 25% and 50% DOD operations, respectively, at a low loading level of SWCNT. This performance was compared with CNT-free cells and cells with a multiwall carbon nanotube (MWCNT) additive. The outstanding performance of the lead-acid cells with the SWCNT additive is due to the oxidative stability of the positive plates during charging and the efficient reduction in sulfation in both plates while forming conducting active-material matrices.

  9. Results of electric-vehicle propulsion system performance on three lead-acid battery systems

    NASA Technical Reports Server (NTRS)

    Ewashinka, J. G.

    1984-01-01

    Three types of state of the art 6 V lead acid batteries were tested. The cycle life of lead acid batteries as a function of the electric vehicle propulsion system design was determined. Cycle life, degradation rate and failure modes with different battery types (baseline versus state of the art tubular and thin plate batteries) were compared. The effects of testing strings of three versus six series connected batteries on overall performance were investigated. All three types do not seem to have an economically feasible battery system for the propulsion systems. The tubular plate batteries on the load leveled profile attained 235 cycles with no signs of degradation and minimal capacity loss.

  10. Influence of measurement procedure on quality of impedance spectra on lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Budde-Meiwes, Heide; Kowal, Julia; Sauer, Dirk Uwe; Karden, Eckhard

    Many battery simulation models, but also electrochemical interpretations are based on impedance spectroscopy. However, the impedance of a battery is influenced by various factors, e.g. in the case of a lead-acid battery: state of charge (SOC), charging or discharging, superimposed dc current, short-term history or homogeneity of the electrolyte. This paper analyses the impact of those factors on impedance spectra of lead-acid batteries. The results show that very detailed information about the conditions during the measurement is crucial for the correct interpretation of a spectrum.

  11. Lead-acid battery use in the development of renewable energy systems in China

    NASA Astrophysics Data System (ADS)

    Chang, Yu; Mao, Xianxian; Zhao, Yanfang; Feng, Shaoli; Chen, Hongyu; Finlow, David

    Policies and laws encouraging the development of renewable energy systems in China have led to rapid progress in the past 2 years, particularly in the solar cell (photovoltaic) industry. The development of the photovoltaic (PV) and wind power markets in China is outlined in this paper, with emphasis on the utilization of lead-acid batteries. The storage battery is a key component of PV/wind power systems, yet many deficiencies remain to be resolved. Some experimental results are presented, along with examples of potential applications of valve regulated lead-acid (VRLA) batteries, both the absorbed glass mat (AGM) and gelled types.

  12. Results of electric-vehicle propulsion system performance on three lead-acid battery systems

    NASA Technical Reports Server (NTRS)

    Ewashinka, J. G.

    1984-01-01

    Three types of state of the art 6 V lead acid batteries were tested. The cycle life of lead acid batteries as a function of the electric vehicle propulsion system design was determined. Cycle life, degradation rate and failure modes with different battery types (baseline versus state of the art tubular and thin plate batteries were compared. The effects of testing strings of three versus six series connected batteries on overall performance were investigated. All three types do not seem to have an economically feasible battery system for the propulsion systems. The tubular plate batteries on the load leveled profile attained 235 cycles with no signs of degradation and minimal capacity loss.

  13. The influence of rubber separators on electrochemical behavior of lead-acid batteries

    SciTech Connect

    Paik, S.L.

    1996-11-01

    This paper presents manufacturing processes; physical, chemical and electrochemical properties; performance in batteries; and their applications of currently available three types of rubber separators. Many aspects of lead-acid battery performance characteristics which are unique electrochemical properties of rubber separators are given. During the early period of lead-acid batteries and their separator development, introduction of microporous hard rubber separators greatly improved performances of lead-acid batteries over wood separators extending battery life and improving cold cranking capabilities. Even after the coming of age of microporous plastic separators, rubber separators have maintained a unique position in the battery industry due to certain performance characteristics which could only be found in microporous rubber separators. Presently, there are several types of separators which differ by their material composition, namely separators made of plastic (polyethylene, polyvinyl chloride, phenolic resorcinol), fiber glass, resin impregnated cellulosic paper and rubber. The performance success of microporous hard rubber separators over the years lead to the introduction of two new variations of rubber products. These are electron beam radiation crosslinked microporous flexible rubber separators and coated fiber glass mat separators containing rubber. In addition to providing physical, mechanical and chemical requirements necessary for designing good lead-acid batteries, rubber separators impart electrochemical performance characteristics which enhance overall performance of battery.

  14. Advanced Raman Spectroscopy of Methylammonium Lead Iodide: Development of a Non-destructive Characterisation Methodology

    PubMed Central

    Pistor, Paul; Ruiz, Alejandro; Cabot, Andreu; Izquierdo-Roca, Victor

    2016-01-01

    In recent years, there has been an impressively fast technological progress in the development of highly efficient lead halide perovskite solar cells. However, the stability of perovskite films and respective solar cells is still an open point of concern and calls for advanced characterization methods. In this work, we identify appropriate measurement conditions for a meaningful analysis of spin-coated absorber-grade perovskite thin films based on methylammonium (MA) lead iodide (MAPbI3) by Raman spectroscopy. The material under investigation and its derivates is the most commonly used for high efficiency devices in the literatures and has yielded working solar cell devices with efficiencies around 10% in our laboratory. We report highly detailed Raman spectra obtained with excitation at 532 nm and 633 nm and their deconvolution taking advantage of the simultaneous fitting of spectra obtained with varying excitation wavelengths. Finally, we propose a fast and contactless methodology based on Raman to probe composition variations and/or degradation of these perovskite thin films and discuss the potential of the presented technique as quality control and degradation monitoring tool in other organic-inorganic perovskite materials and complete solar cell devices. PMID:27786250

  15. Advanced Raman Spectroscopy of Methylammonium Lead Iodide: Development of a Non-destructive Characterisation Methodology

    NASA Astrophysics Data System (ADS)

    Pistor, Paul; Ruiz, Alejandro; Cabot, Andreu; Izquierdo-Roca, Victor

    2016-10-01

    In recent years, there has been an impressively fast technological progress in the development of highly efficient lead halide perovskite solar cells. However, the stability of perovskite films and respective solar cells is still an open point of concern and calls for advanced characterization methods. In this work, we identify appropriate measurement conditions for a meaningful analysis of spin-coated absorber-grade perovskite thin films based on methylammonium (MA) lead iodide (MAPbI3) by Raman spectroscopy. The material under investigation and its derivates is the most commonly used for high efficiency devices in the literatures and has yielded working solar cell devices with efficiencies around 10% in our laboratory. We report highly detailed Raman spectra obtained with excitation at 532 nm and 633 nm and their deconvolution taking advantage of the simultaneous fitting of spectra obtained with varying excitation wavelengths. Finally, we propose a fast and contactless methodology based on Raman to probe composition variations and/or degradation of these perovskite thin films and discuss the potential of the presented technique as quality control and degradation monitoring tool in other organic-inorganic perovskite materials and complete solar cell devices.

  16. Relation between urinary beta-aminoisobutyric acid excretion and concentration of lead in the blood of workers occupationally exposed to lead.

    PubMed

    Tomokuni, K; Ichiba, M; Mori, K

    1992-05-01

    Urinary beta-aminoisobutyric acid (ABA) concentration was determined by fluorometric high performance liquid chromatography in 22 workers occupationally exposed to lead. The urinary excretion of ABA was increased with increasing exposure to lead. The excretion of urinary ABA had a significant correlation with concentration of lead in blood (Pb-B) (r = 0.581), similar to the correlation of Pb-B with urinary delta-aminolaevulinic acid (ALA) concentration (r = 0.563). The determination of urinary ABA concentration in workers exposed to lead, therefore, may offer a new approach for evaluating the health effect of lead.

  17. Relationships between blood lead concentration and aminolevulinic acid dehydratase in alcoholics and workers industrially exposed to lead

    SciTech Connect

    Bortoli, A.; Fazzin, G.; Marin, V.; Trabuio, G.; Zotti, S.

    1986-07-01

    Blood lead concentration (Pb-B), aminolevulinic acid dehydratase (ALAD), and gamma-GT were measured in 265 workers industrially exposed to lead and in 184 patients with liver disease resulting from alcohol consumption. The first group was divided according to alcohol use, i.e., nondrinkers, moderate drinkers, and heavy drinkers. The second group was divided according to the following criteria: hepatopatic without cirrhosis, hepatopatic with compensated cirrhosis, and hepatopatic with decompensated cirrhosis. Heavy drinkers who were industrially exposed had the highest Pb-B (40.4 +/- 14.6 micrograms/dl) and the lowest ALAD (22.2 +/- 9.1 U/L). The correlations between Pb-B and ALAD show no significant change with the increase of Pb-B. In the alcoholic group, 76 patients with alcoholic liver disease without cirrhosis had the highest Pb-B (40.3-9.1 micrograms/dl) and ALAD the lowest (18.6 +/- 7.7 U/L). The negative correlation between Pb-B and log ALAD disappeared completely in individuals with Pb-B that exceeded 50 micrograms/dl, independent from the seriousness of illness.

  18. Effect of organic acids on the adsorption of copper, lead, and zinc by goethite

    NASA Astrophysics Data System (ADS)

    Perelomov, L. V.; Pinskiy, D. L.; Violante, A.

    2011-01-01

    The adsorption of Cu, Pb, and Zn by synthetic goethite was studied in the absence and presence of oxalic, citric, and glutamic acids at different pH values. It was shown that, in the absence of an acid, the content of adsorbed metals increased with the increasing pH. The content of adsorbed cations at constant pH values decreased in the sequence: Cu > Pb > Zn. The simultaneous addition of metal cations and organic acids to the goethite suspension increased the content of the adsorbed elements. The oxalic and citric acids had similar effects on the adsorption of copper and lead in the studied pH range. The metal: acid concentration ratios significantly affected the adsorption of the heavy metals by goethite. An increase in the metal adsorption was observed to a certain metal: acid ratio, which was followed by a gradual decrease. The adsorption of the metals by goethite also depended on the properties of the metal cations and the organic ligands. The observed tendencies were attributed to the complexation of heavy metals with organic acid anions and the simultaneous sorption of acids at positively charged sites on the goethite surface with the formation of mineral-organic compounds, which significantly modified the surface properties of the mineral. The study of the effect of increasing lead concentrations in the solution on the copper adsorption by goethite in the absence, in the presence, and at the addition of an oxalic acid solution to the goethite suspension one hour before the beginning of the experiment showed that lead decreased the adsorption of copper in all the treatments. The possible mechanisms of the processes occurring in the system were considered.

  19. Association between delta-aminolevulinic acid dehydratase polymorphism and placental lead levels.

    PubMed

    Kayaaltı, Zeliha; Sert, Selda; Kaya-Akyüzlü, Dilek; Söylemez, Esma; Söylemezoğlu, Tülin

    2016-01-01

    Lead inhibits the delta-aminolevulinic acid dehydratase (ALAD) activity and results in neurotoxic aminolevulinic acid accumulation in the blood. During pregnancy, lead in the maternal blood can easily cross the placenta. The aim of this study was to determine whether the maternal ALAD G177C polymorphism (rs1800435) was related to the placental lead levels. The study population comprised 97 blood samples taken from mothers to investigate ALAD G177C polymorphism and their placentas to measure lead levels. ALAD G177C polymorphism was detected by standard polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) technique and atomic absorption spectrometry (AAS) equipped with a graphite furnace and Zeeman background correction system was used for lead determination. The median placental lead levels for ALAD1-1, ALAD1-2 and ALAD2-2 genotypes were 7.54 μg/kg, 11.78 μg/kg and 18.53 μg/kg, respectively. Statistically significant association was found between the maternal ALAD G177C polymorphism and placental lead levels (p<0.05). This study suggested that maternal ALAD G177C polymorphism was associated with placental lead levels.

  20. Changes in primary metabolism leading to citric acid overflow in Aspergillus niger.

    PubMed

    Legisa, Matic; Mattey, Michael

    2007-02-01

    For citric acid-accumulating Aspergillus niger cells, the enhancement of anaplerotic reactions replenishing tricarboxylic acid cycle intermediates predisposes the cells to form the product. However, there is no increased citrate level in germinating spores and a complex sequence of developmental events is needed to change the metabolism in a way that leads to an increased level of tricarboxylic acid cycle intermediates in mycelia. A review of physiological events that cause such intracellular conditions, with the special emphasis on the discussion of hexose transport into the cells and regulation of primary metabolism, predominantly of glycolytic flux during the process, is presented.

  1. Metabolic engineering in the biotechnological production of organic acids in the tricarboxylic acid cycle of microorganisms: Advances and prospects.

    PubMed

    Yin, Xian; Li, Jianghua; Shin, Hyun-Dong; Du, Guocheng; Liu, Long; Chen, Jian

    2015-11-01

    Organic acids, which are chemically synthesized, are also natural intermediates in the metabolic pathways of microorganisms, among which the tricarboxylic acid (TCA) cycle is the most crucial route existing in almost all living organisms. Organic acids in the TCA cycle include citric acid, α-ketoglutaric acid, succinic acid, fumaric acid, l-malic acid, and oxaloacetate, which are building-block chemicals with wide applications and huge markets. In this review, we summarize the synthesis pathways of these organic acids and review recent advances in metabolic engineering strategies that enhance organic acid production. We also propose further improvements for the production of organic acids with systems and synthetic biology-guided metabolic engineering strategies.

  2. Al/Pb lightweight grids prepared by molten salt electroless plating for application in lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Hong, Bo; Jiang, Liangxing; Hao, Ketao; Liu, Fangyang; Yu, Xiaoying; Xue, Haitao; Li, Jie; Liu, Yexiang

    2014-06-01

    In this paper, a lightweight Pb plated Al (Al/Pb) grid was prepared by molten salt electroless plating. The SEM and bonding strength test show that the lead coating is deposited with a smooth surface and firm combination. CV test shows that the electrochemical properties of Al/Pb electrodes are stable. 2.0 V single-cell flooded lead-acid batteries with Al/Pb grids as negative collectors are assembled and the performances including 20 h capacity, rate capacity, cycle life, internal resistance are investigated. The results show that the cycle life of Al/Pb-grid cells is about 475 cycles and can meet the requirement of lead-acid batteries. Al/Pb grids are conducive to the refinement of PbSO4 grain, and thereby reduce the internal resistance of battery and advance the utilization of active mass. Moreover, weight of Al/Pb grid is only 55.4% of the conventional-grid. In this way, mass specific capacity of Al/Pb-grid negatives is 17.8% higher and the utilization of active mass is 6.5% higher than conventional-grid negatives.

  3. Lead exposure changes gastric acid secretion in rat: role of nitric oxide (NO).

    PubMed

    Vahedian, Zakieh; Nabavizadeh, Fatemeh; Keshavarz, Mansoor; Vahedian, Jalal; Mirershadi, Fatemeh

    2011-01-01

    Sub chronic exposure to lead in rats slows gastric emptying, but little is known about the effects of lead on gastric secretion. This study was designed to investigate the effects of lead on gastric acid secretion and its possible mechanisms in rats. Lead acetate was dissolved in drinking water in a concentration of 1%. Sodium acetate-containing water with a molar concentration similar to lead was also prepared. We had nine groups of animals (n=8); four of them were exposed to lead for 1, 2, 3, and 4 weeks (Pb1, Pb2, Pb3 and Pb4 groups, respectively). Sodium acetate solution was given to another four groups for 1, 2, 3, and 4 weeks (Na1, Na2, Na3 and Na4 groups, respectively). Gastric secretion was collected by washout technique and its acid output was measured in the basal (Basal Acid Output, BAO), vogotomy (Vagotomized Acid Output, VAO), and vagally stimulated (Vagally Stimulated Acid Output, VSAO) states using titrator instrument. Nitric oxide (NO) metabolite of gastric tissue was determined by Griess micro assay method to evaluate the possible mechanism of lead effect on gastric secretion. VSAO was significantly less in Pb1 and Pb2 groups than Na1 and Na2 ones respectively (1.75 ± 0.17, 2.10 ± 0.30 vs. 5.79 ± 0.20, 6.18 ± 0.27 µmol/15min) (P=0.001, P=0.001). BAO was significantly more in Pb3 and Pb4 groups than Na3 and Na4 ones respectively (2.77 ± 0.37, 2.80 ± 0.31 vs. 1.73 ± 0.16, 1.79 ± 0.34 µmol/15min) (P=0.01, P=0.02), but it was the same after vagotomy. VSAO was more in Pb3 and Pb4 groups than their Na counterparts (P=0.001, P=0.0001). NO metabolite of gastric tissue was more in all Pb groups in comparison to their Na counterparts (P=0.0001). In this study, it seems that lead exposure, via NO mechanism, has different effects on acid secretion. Nitric oxide in small and large amounts decrease and increase gastric acid secretion, respectively.

  4. Recent Advances in Sialic Acid-Focused Glycomics

    PubMed Central

    Nie, Huan; Li, Yu; Sun, Xue-Long

    2012-01-01

    Recent emergences of glycobiology, glycotechnology and glycomics have been clarifying enormous roles of carbohydrates in biological recognition systems. For example, cell surface carbohydrates existing as glycoconjugates (glycolipids, glycoproteins and proteoglycans) play crucial roles in cell-cell communication, cell proliferation and differentiation, tumor metastasis, inflammatory response or viral infection. In particular, sialic acids (SAs) existing as terminal residues in carbohydrate chains on cell surface are involved in signal recognition and adhesion to ligands, antibodies, enzymes and microbes. In addition, plasma free SAs and sialoglycans have shown great potential for disease biomarker discovery. Therefore, development of efficient analytical methods for structural and functional studies of SAs and sialylglycans are very important and highly demanded. The problems of SAs and sialylglycans analysis are vanishingly small sample amount, complicated and unstable structures, and complex mixtures. Nevertheless, in the past decade, mass spectrometry in combination with chemical derivatization and modern separation methodologies has become a powerful and versatile technique for structural analysis of SAs and sialylglycans. This review summarizes these recent advances in glycomic studies on SAs and sialylglycans. Specially, derivatization and capturing of SAs and sialylglycans combined with mass spectrometry analysis are highlighted. PMID:22513219

  5. Locomotor damage and brain oxidative stress induced by lead exposure are attenuated by gallic acid treatment.

    PubMed

    Reckziegel, Patrícia; Dias, Verônica Tironi; Benvegnú, Dalila; Boufleur, Nardeli; Silva Barcelos, Raquel Cristine; Segat, Hecson Jesser; Pase, Camila Simonetti; Dos Santos, Clarissa Marques Moreira; Flores, Erico Marlon Moraes; Bürger, Marilise Escobar

    2011-05-30

    We investigated the antioxidant potential of gallic acid (GA), a natural compound found in vegetal sources, on the motor and oxidative damages induced by lead. Rats exposed to lead (50 mg/kg, i.p., once a day, 5 days) were treated with GA (13.5mg/kg, p.o.) or EDTA (110 mg/kg, i.p.) daily, for 3 days. Lead exposure decreased the locomotor and exploratory activities, reduced blood ALA-D activity, and increased brain catalase (CAT) activity without altering other antioxidant defenses. Brain oxidative stress (OS) estimated by lipid peroxidation (TBARS) and protein carbonyl were increased by lead. GA reversed the motor behavior parameters, the ALA-D activity, as well as the markers of OS changed by lead exposure. CAT activity remained high, possibly as a compensatory mechanism to eliminate hydroperoxides during lead poisoning. EDTA, a conventional chelating agent, was not beneficial on the lead-induced motor behavior and oxidative damages. Both GA (less) and EDTA (more) reduced the lead accumulation in brain tissue. Negative correlations were observed between the behavioral parameters and lipid peroxidation and the lead levels in brain tissue. In conclusion, GA may be an adjuvant in lead exposure, mainly by its antioxidant properties against the motor and oxidative damages resulting from such poisoning.

  6. Program to analyze the failure mode of lead-acid batteries

    SciTech Connect

    Zuckerbrod, D.

    1986-03-01

    The electrical characteristics of large lead-acid cells from nuclear power plants were studied. The overall goal was to develop nondestructive tests to predict cell failure using this easily obtained information. Cell capacitance, internal resistance, reaction resistance for hydrogen evolution and cell capacity were measured on a lead-calcium cell in good condition. A high float voltage and low internal resistance were found to correlate with good cell capacity in cells selected from a set of six lead-antimony cells in poor condition.

  7. Elevated urinary excretion of beta-aminoisobutyric acid and exposure to inorganic lead.

    PubMed

    Farkas, W R; Fischbein, A; Solomon, S; Buschman, F; Borek, E; Sharma, O K

    1987-01-01

    beta-Aminoisobutyric acid (beta-AIB), a normal degradation product of thymine, a constituent of DNA and, to a lesser extent, of transfer RNA, is excreted in low levels in human urine. We found that a group of iron workers occupationally exposed to inorganic lead excreted high levels of urinary beta-AIB. Elevated urinary excretion of beta-AIB was also observed in marmosets, Callithrix jacchus, that received lead acetate in drinking water. Our results suggest that increased urinary excretion of beta-AIB could stem from damage to DNA on exposure to lead.

  8. Degradation of herbicide 4-chlorophenoxyacetic acid by advanced electrochemical oxidation methods.

    PubMed

    Boye, Birame; Dieng, Momar M; Brillas, Enric

    2002-07-01

    The herbicide 4-chlorophenoxyacetic acid (4-CPA) has been degraded in aqueous medium by advanced electrochemical oxidation processes such as electro-Fenton and photoelectro-Fenton with UV light, using an undivided cell containing a Pt anode. In these environmentally clean methods, the main oxidant is the hydroxyl radical produced from Fenton's reaction between Fe2+ added to the medium and H2O2 electrogenerated from an 02-diffusion cathode. Solutions of a 4-CPA concentration <400 ppm within the pH range of 2.0-6.0 at 35 degrees C can be completely mineralized at low current by photoelectro-Fenton, while electro-Fenton leads to ca. 80% of mineralization. 4-CPA is much more slowly degraded by anodic oxidation in the absence and presence of electrogenerated H2O2. 4-Chlorophenol, 4-chlorocatechol, and hydroquinone are identified as aromatic intermediates by CG-MS and quantified by reverse-phase chromatography. Further oxidation of these chloroderivatives yields stable chloride ions. Generated carboxylic acids such as glycolic, glyoxylic, formic, malic, maleic, fumaric, and oxalic are followed by ion exclusion chromatography. The highest mineralization rate found for photoelectro-Fenton is accounted for by the fast photodecomposition of complexes of Fe3+ with such short-chain acids, mainly oxalic acid, under the action of UV light.

  9. {Delta}-Aminolevulinic acid dehydratase: A sensitive indicator of lead exposure in broiler chicks: (Gallus domesticus)

    SciTech Connect

    Bakalli, R.I.; Pesti, G.M.; Konjufca, V.

    1995-12-01

    Delta-aminolevulinic acid dehydratase, EC 4.2.1.24 (ALAD) is one of the enzymes participating in heme synthesis. The study reported in this paper was designed to determine the activity of erythrocyte ALAD anbd the relationship between this enzyme and tissue lead levels in chickens, during Pb intake and after withdrawing Bv from the feed. 20 refs., 3 tabs.

  10. Designing lead-acid batteries to meet energy and power requirements of future automobiles

    NASA Astrophysics Data System (ADS)

    Moseley, Patrick T.; Rand, David A. J.; Monahov, Boris

    2012-12-01

    A review is given of the factors that mitigate against the successful use of lead-acid batteries in the high-rate partial-state-of-charge (HRPSoC) duties experienced in hybrid electric vehicles, together with a consideration of successful remedies for those factors.

  11. Using Diagnostic Assessment to Help Teachers Understand the Chemistry of the Lead-Acid Battery

    ERIC Educational Resources Information Center

    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…

  12. Determination of an ageing factor for lead/acid batteries. 1. Kinetic aspects

    NASA Astrophysics Data System (ADS)

    Armenta-Deu, C.; Donaire, T.

    The capacity of lead/acid batteries decreases with the number of cycles. This process is known as ageing. The reduction of capacity affects not only the operation time but also the performance of the accumulator and of the system attached to the battery. One of the main procedures affected by the battery ageing is the determination of the state-of-charge. In this paper, a parameter called 'ageing factor', fa, which represents the reduction of the available energy in lead/acid batteries, is introduced. A method to calculate this factory and its incidence on battery performance has also been developed. The method is intended to predict 'ageing' effects on lead/acid batteries as a non-destructive method, as well as on-line battery operation. The method is based on the effective reduction in electrolyte specific gravity in a fully charged lead/acid battery computed from the change of the slope of the electrolyte density during charge with the number of cycles, and the subsequent reduction in discharge time. A correlation process between the reduction of the energy delivered by the electrochemical cell, the reduction of the discharge time, and the apparent change of the slope of electrolyte density has been developed, resulting in an analytical expression that may be used to compute the effective reduction in available energy in lead/acid batteries. The results of the experiments have proven the merit of the proposed system: the predicted values are in good agreement with experimental data, the associated error in the a estimation being lower than 9%, a result which has been considered acceptable to validate the proposed method.

  13. Recent Advances in Developing Small Molecules Targeting Nucleic Acid

    PubMed Central

    Wang, Maolin; Yu, Yuanyuan; Liang, Chao; Lu, Aiping; Zhang, Ge

    2016-01-01

    Nucleic acids participate in a large number of biological processes. However, current approaches for small molecules targeting protein are incompatible with nucleic acids. On the other hand, the lack of crystallization of nucleic acid is the limiting factor for nucleic acid drug design. Because of the improvements in crystallization in recent years, a great many structures of nucleic acids have been reported, providing basic information for nucleic acid drug discovery. This review focuses on the discovery and development of small molecules targeting nucleic acids. PMID:27248995

  14. Using Acid Number as a Leading Indicator of Refrigeration and Air Conditioning System Performance

    SciTech Connect

    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

  15. New strategies in metastatic melanoma: oncogene-defined taxonomy leads to therapeutic advances.

    PubMed

    Flaherty, Keith T; Fisher, David E

    2011-08-01

    The discovery of BRAF and KIT mutations provided the first basis for a molecular classification of cutaneous melanoma on therapeutic grounds. As BRAF-targeted therapy quickly moves toward regulatory approval and incorporation as standard therapy for patients with metastatic disease, proof of concept has also been established for targeting mutated KIT in melanoma. NRAS mutations have long been known to be present in a subset of melanomas and represent an elusive subgroup for targeted therapies. Matching patient subgroups defined by genetic aberrations in the phosphoinositide 3-kinase and p16/cyclin dependent kinase 4 (CDK4) pathways with appropriate targeted therapies has not yet been realized. And, an increasing understanding of lineage-specific transcriptional regulators, most notably MITF, and how they may play a role in melanoma pathophysiology, has provided another axis to approach with therapies. The foundation has been established for individual oncogene targeting, and current investigations seek to understand the intersection of these susceptibilities and other described potential targets and pathways. The melanoma field stands poised to take the lead among cancer subtypes in advancing combination therapy strategies that simultaneously target multiple biologic underpinnings of the disease.

  16. Molecular Advances Leading to Treatment Implications for Fragile X Premutation Carriers

    PubMed Central

    Polussa, Jonathan; Schneider, Andrea; Hagerman, Randi

    2014-01-01

    Fragile X syndrome (FXS) is the most common single gene cause of intellectual disability and it is characterized by a CGG expansion of more than 200 repeats in the FMR1 gene, leading to methylation of the promoter and gene silencing. The fragile X premutation, characterized by a 55 to 200 CGG repeat expansion, causes health problems and developmental difficulties in some, but not all, carriers. The premutation causes primary ovarian insufficiency in approximately 20% of females, psychiatric problems (including depression and/or anxiety) in approximately 50% of carriers and a neurodegenerative disorder, the fragile X-associated tremor ataxia syndrome (FXTAS), in approximately 40% of males and 16% of females later in life. Recent clinical studies in premutation carriers have expanded the health problems that may be seen. Advances in the molecular pathogenesis of the premutation have shown significant mitochondrial dysfunction and oxidative stress in neurons which may be amenable to treatment. Here we review the clinical problems of carriers and treatment recommendations. PMID:25436181

  17. Influence of 2,3-dimercaptosuccinic acid on gastrointestinal lead absorption and whole-body lead retention

    SciTech Connect

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

    1989-03-01

    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 {sup 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{sub 3})2) plus 15 microCi {sup 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.

  18. Discrete carbon nanotubes increase lead acid battery charge acceptance and performance

    NASA Astrophysics Data System (ADS)

    Swogger, Steven W.; Everill, Paul; Dubey, D. P.; Sugumaran, Nanjan

    2014-09-01

    Performance demands placed upon lead acid batteries have outgrown the technology's ability to deliver. These demands, typically leading to Negative Active Material (NAM) failure, include: short, high-current surges; prolonged, minimal, overvoltage charging; repeated, Ah deficit charging; and frequent deep discharges. Research shows these failure mechanisms are attenuated by inclusion of carbon allotropes into the NAM. Addition of significant quantities of carbon, however, produces detrimental changes in paste rheology, leading to lowered industrial throughput. Additionally, capacity, cold-cranking performance, and other battery metrics are negatively affected at high carbon loads. Presented here is Molecular Rebar® Lead Negative, a new battery additive comprising discrete carbon nanotubes (dCNT) which uniformly disperse within battery pastes during mixing. NS40ZL batteries containing dCNT show enhanced charge acceptance, reserve capacity, and cold-cranking performance, decreased risk of polarization, and no detrimental changes to paste properties, when compared to dCNT-free controls. This work focuses on the dCNT as NAM additives only, but early-stage research is underway to test their functionality as a PAM additive. Batteries infused with Molecular Rebar® Lead Negative address the needs of modern lead acid battery applications, produce none of the detrimental side effects associated with carbon additives, and require no change to existing production lines.

  19. Differently Structured Advance Organizers Lead to Different Initial Schemata and Learning Outcomes

    ERIC Educational Resources Information Center

    Gurlitt, Johannes; Dummel, Sebastian; Schuster, Silvia; Nuckles, Matthias

    2012-01-01

    Does the specific structure of advance organizers influence learning outcomes? In the first experiment, 48 psychology students were randomly assigned to three differently structured advance organizers: a well-structured, a well-structured and key-concept emphasizing, and a less structured advance organizer. These were followed by a sorting task, a…

  20. Recent advances in amino acid production by microbial cells.

    PubMed

    Hirasawa, Takashi; Shimizu, Hiroshi

    2016-12-01

    Amino acids have been utilized for the production of foods, animal feeds and pharmaceuticals. After the discovery of the glutamic acid-producing bacterium Corynebacterium glutamicum by Japanese researchers, the production of amino acids, which are primary metabolites, has been achieved using various microbial cells as hosts. Recently, metabolic engineering studies on the rational design of amino acid-producing microbial cells have been successfully conducted. Moreover, the technology of systems biology has been applied to metabolic engineering for the creation of amino acid-producing microbial cells. Currently, new technologies including synthetic biology, single-cell analysis, and evolutionary engineering have been utilized to create amino acid-producing microbial cells. In addition, useful compounds from amino acids have been produced by microbial cells. Here, current researches into the metabolic engineering of microbial cells toward production of amino acids and amino acid-related compounds are reviewed.

  1. Simultaneous Removal of Lindane, Lead and Cadmium from Soils by Rhamnolipids Combined with Citric Acid

    PubMed Central

    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

  2. Combined effects of lead and acid rain on photosynthesis in soybean seedlings.

    PubMed

    Hu, Huiqing; Wang, Lihong; Liao, Chenyu; Fan, Caixia; Zhou, Qing; Huang, Xiaohua

    2014-10-01

    To explore how lead (Pb) and acid rain simultaneously affect plants, the combined effects of Pb and acid rain on the chlorophyll content, chlorophyll fluorescence reaction, Hill reaction rate, and Mg(2+)-ATPase activity in soybean seedlings were investigated. The results indicated that, when soybean seedlings were treated with Pb or acid rain alone, the chlorophyll content, Hill reaction rate, Mg(2+)-ATPase activity, and maximal photochemical efficiency (F(v)/F(m)) were decreased, while the initial fluorescence (F 0) and maximum quantum yield (Y) were increased, compared with those of the control. The combined treatment with Pb and acid rain decreased the chlorophyll content, Hill reaction rate, Mg(2+)-ATPase activity, F(v)/F(m), and Y and increased F 0 in soybean seedlings. Under the combined treatment with Pb and acid rain, the two factors showed additive effects on the chlorophyll content in soybean seedlings and exhibited antagonistic effects on the Hill reaction rate. Under the combined treatment with high-concentration Pb and acid rain, the two factors exhibited synergistic effects on the Mg(2+)-ATPase activity, F 0, F v/F m, as well as Y. In summary, the inhibition of the photosynthetic process is an important physiological basis for the simultaneous actions of Pb and acid rain in soybean seedlings.

  3. Delta-aminolevulinic acid dehydratase (ALAD) polymorphism in lead exposed Bangladeshi children and its effect on urinary aminolevulinic acid (ALA)

    SciTech Connect

    Tasmin, Saira; Furusawa, Hana; Ahmad, Sk. Akhtar; Watanabe, Chiho

    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.

  4. Ammonia and amino acid profiles in liver cirrhosis: effects of variables leading to hepatic encephalopathy.

    PubMed

    Holecek, Milan

    2015-01-01

    Hyperammonemia and severe amino acid imbalances play central role in hepatic encephalopathy (HE). In the article is demonstrated that the main source of ammonia in cirrhotic subjects is activated breakdown of glutamine (GLN) in enterocytes and the kidneys and the main source of GLN is ammonia detoxification to GLN in the brain and skeletal muscle. Branched-chain amino acids (BCAA; valine, leucine, and isoleucine) decrease due to activated GLN synthesis in muscle. Aromatic amino acids (AAA; phenylalanine, tyrosine, and tryptophan) and methionine increase due to portosystemic shunts and reduced ability of diseased liver. The effects on aminoacidemia of the following variables that may affect the course of liver disease are discussed: nutritional status, starvation, protein intake, inflammation, acute hepatocellular damage, bleeding from varices, portosystemic shunts, hepatic cancer, and renal failure. It is concluded that (1) neither ammonia nor amino acid concentrations correlate closely with the severity of liver disease; (2) BCAA/AAA ratio could be used as a good index of liver impairment and for early detection of derangements in amino acid metabolism; (3) variables potentially leading to overt encephalopathy exert substantial but uneven effects; and (4) careful monitoring of ammonia and aminoacidemia may discover important break points in the course of liver disease and indicate appropriate therapeutic approach. Of special importance might be isoleucine deficiency in bleeding from varices, arginine deficiency in sepsis, and a marked rise of GLN and ammonia levels that may appear in all events leading to HE.

  5. Plasma and neutrophil fatty acid composition in advanced cancer patients and response to fish oil supplementation.

    PubMed

    Pratt, V C; Watanabe, S; Bruera, E; Mackey, J; Clandinin, M T; Baracos, V E; Field, C J

    2002-12-02

    Metabolic demand and altered supply of essential nutrients is poorly characterised in patients with advanced cancer. A possible imbalance or deficiency of essential fatty acids is suggested by reported beneficial effects of fish oil supplementation. To assess fatty acid status (composition of plasma and neutrophil phospholipids) in advanced cancer patients before and after 14 days of supplementation (12+/-1 g day(-1)) with fish (eicosapentaenoic acid, and docosahexaenoic acid) or placebo (olive) oil. Blood was drawn from cancer patients experiencing weight loss of >5% body weight (n=23). Fatty acid composition of plasma phospholipids and the major phospholipid classes of isolated neutrophils were determined using gas liquid chromatography. At baseline, patients with advanced cancer exhibited low levels (<30% of normal values) of plasma phospholipids and constituent fatty acids and elevated 20 : 4 n-6 content in neutrophil phospholipids. High n-6/n-3 fatty acid ratios in neutrophil and plasma phospholipids were inversely related to body mass index. Fish oil supplementation raised eicosapentaenoic acid and docosahexaenoic acid content in plasma but not neutrophil phospholipids. 20 : 4 n-6 content was reduced in neutrophil PI following supplementation with fish oil. Change in body weight during the supplementation period related directly to increases in eicosapentaenoic acid in plasma. Advanced cancer patients have alterations in lipid metabolism potentially due to nutritional status and/or chemotherapy. Potential obstacles in fatty acid utilisation must be addressed in future trials aiming to improve outcomes using nutritional intervention with fish oils.

  6. Mobilization of lead by esters of meso-2,3-dimercaptosuccinic acid

    SciTech Connect

    Singh, P.K.; Jones, M.M.; Xu, Z.; Gale, G.R.; Smith, A.B.; Atkins, L.M. )

    1989-01-01

    An examination was made of the relative efficacies of 2,3-dimercapto-1-propanol (BAL) and three diesters (CH(SH)COOR)2; DMDMS, R = CH3; DEDMS, R = C2H5; and Di-PDMS, R = CH(CH3)2 of meso-2,3-dimercaptosuccinic acid (DMSA) in mobilizing freshly injected lead from mice. These diesters, like BAL, reduced the lead levels resulting from freshly injected lead in both the soft tissues (liver, kidneys, spleen, and brain) and the bone (tibia). After treatment with the dimethyl (DMDMS), the diethyl (DEDMS), and the diisopropyl (Di-PDMS) esters the lead content of each of the organs was significantly less than that present in the untreated controls. Each of the diesters reduced lead levels in the kidneys, liver, and spleen significantly below those levels found after BAL treatment. The action of the diesters in reducing brain lead levels was comparable to that of BAL. Di-PDMS was the most effective of these compounds and was significantly superior to BAL. Each of the esters was also significantly more effective than BAL in reducing the whole body level of lead.

  7. Research Advances: DNA Computing Targets West Nile Virus, Other Deadly Diseases, and Tic-Tac-Toe; Marijuana Component May Offer Hope for Alzheimer's Disease Treatment; New Wound Dressing May Lead to Maggot Therapy--Without the Maggots

    ERIC Educational Resources Information Center

    King, Angela G.

    2007-01-01

    This article presents three reports of research advances. The first report describes a deoxyribonucleic acid (DNA)-based computer that could lead to faster, more accurate tests for diagnosing West Nile Virus and bird flu. Representing the first "medium-scale integrated molecular circuit," it is the most powerful computing device of its type to…

  8. Study of the influence of carbon on the negative lead-acid battery electrodes

    NASA Astrophysics Data System (ADS)

    Bača, Petr; Micka, Karel; Křivík, Petr; Tonar, Karel; Tošer, Pavel

    Experiments were made with negative lead-acid battery electrodes doped with different concentrations of powdered carbon. It turned out that the rate of formation decreased with the rising concentration of carbon added into the active material. During accelerated cycling in the PSoC regime, the cycle life showed a maximum at a concentration of carbon near 1%, whereas at lower or higher concentrations the cycle life was profoundly lower. A marked increase of the active mass resistance with the cycle number was recorded at carbon concentrations above 2%. Orientation experiments showed that compression of the lead-acid laboratory cells caused an increase of the cycle life of the negative electrode in the studied regime.

  9. Effect of positive pulse charge waveforms on the energy efficiency of lead-acid traction cells

    NASA Technical Reports Server (NTRS)

    Smithrick, J. J.

    1981-01-01

    The effects of four different charge methods on the energy conversion efficiency of 300 ampere hour lead acid traction cells were investigated. Three of the methods were positive pulse charge waveforms; the fourth, a constant current method, was used as a baseline of comparison. The positive pulse charge waveforms were: 120 Hz full wave rectified sinusoidal; 120 Hz silicon controlled rectified; and 1 kHz square wave. The constant current charger was set at the time average pulse current of each pulse waveform, which was 150 amps. The energy efficiency does not include charger losses. The lead acid traction cells were charged to 70 percent of rated ampere hour capacity in each case. The results of charging the cells using the three different pulse charge waveforms indicate there was no significant difference in energy conversion efficiency when compared to constant current charging at the time average pulse current value.

  10. Cycle life testing of a 24-V, 15-Ah sealed lead-acid aircraft battery

    SciTech Connect

    Vutetakis, D.G.; Viswanathan, V.V.

    1997-12-01

    This paper presents the results of cycle life testing of 24-V, 15-Ah sealed lead-acid batteries intended for use in the B-1B aircraft. Test samples were procured from two different manufacturers and subjected to cycle testing at 33% and 100% depth-of-discharge (DOD). The cycle life at 33% DOD ranged from 500 to 750 cycles. The cycle life at 100% DOD ranged from 160 to 260 cycles.

  11. Operational testing of valve regulated lead acid batteries in commercial aircraft

    SciTech Connect

    Timmons, J.B.; Koss, E.F.

    1997-12-01

    Valve regulated lead acid (VRLA) batteries provide electrical performance that is virtually identical to sintered plate nickel-cadmium battery systems. In addition, the VRLA batteries offer the user a no maintenance battery and other enhanced features that make this a very desirable battery for aircraft applications. In field trials, where VRLA batteries were substituted for nickel-cadmium batteries, the VRLA provided the user with a high reliability turbine engine starting battery under a wide variety of climatic conditions.

  12. Enhancing the performance of lead-acid batteries with carbon - In pursuit of an understanding

    NASA Astrophysics Data System (ADS)

    Moseley, Patrick T.; Rand, David A. J.; Peters, Ken

    2015-11-01

    The inherently poor dynamic charge-acceptance of the lead-acid battery can be greatly improved by the incorporation of additional carbon to the negative plate. An analysis is undertaken of the various ways by which the carbon may be introduced, and of the proposed mechanisms whereby its presence proves to be beneficial. It is intended that such an investigation should provide a guide to the selection of the optimum carbon inventory.

  13. Electric and hybrid vehicles charge efficiency tests of ESB EV-106 lead-acid batteries

    SciTech Connect

    Rowlette, J.J.

    1981-01-15

    Charge efficiencies were determined for ESB EV-106 lead-acid batteries by measurements made under widely differing conditions of temperature, charge procedure, and battery age. The measurements were used to optimize charge procedures and to evaluate the concept of a modified, coulometric state-of-charge indicator. Charge efficiency determinations were made by measuring gassing rates and oxygen fractions. A novel, positive displacement gas flow meter which proved to be both simple and highly accurate is described and illustrated.

  14. Colloidal 3-mercaptopropionic acid Capped Lead Sulfide Quantum Dots in a Low Boiling Point Solvent.

    PubMed

    Reinhart, Chase C; Johansson, Erik

    2017-04-10

    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 new ligand and stabilizer, and sample age. Nanocrystal ligand chemistry was studied through a combination of (1)H-NMR and 2-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).

  15. A high power spiral wound lead-acid battery for hybrid electric vehicles

    SciTech Connect

    Olson, J.B.; Sexton, E.D.

    1997-12-01

    Optima Batteries, Inc. is currently in development of a high power (660 W/kg) spiral wound lead-acid 6V battery with a nominal capacity of 15 Ah. Its exceptional power and excellent thermal characteristics make it a promising choice for hybrid electric vehicle applications. The hybrid electric vehicle presents a new and unique challenge for energy storage systems. The batteries require high power for acceleration and hill climbing and good charge acceptance for regenerative braking and overall energy efficiency. Since the on board auxiliary power unit results in much lower demands for battery energy capacity, lead-acid batteries fit quite well into these performance requirements. Many of the remaining challenges involve the development of battery management systems which must function to maintain the battery pack at peak performance and achieve an economical cycle life. Related to the issue of battery management is information about conditions that may cause damage or unbalance of the pack. Experiments are described investigating the effects of extreme cell reversal on battery capacity and cycle life. The results demonstrate the amazing robustness of the lead-acid battery for tolerating over discharge.

  16. Low-maintenance, valve-regulated, lead/acid batteries in utility applications

    NASA Astrophysics Data System (ADS)

    Cook, G. M.; Spindler, W. C.

    Electric power utility companies have various needs for lead/acid batteries, and also are beginning to promote customer-side-of-the meter applications for mutual benefits. Increasing use of lead/acid batteries in the future will depend heavily on improving performance and reliability of sealed, recombination designs, and on their versatility for many applications. Classifying various utility uses could be by cycling requirements, depth-of-discharge, power or energy (ratio of watts to hours), or by site (utility or customer). Deep-cycling examples are energy storage, peak-shaving and electric vehicles. Shallow-cycling examples are frequency regulation and reactive power control. Infrequent discharge examples are stationary service and spinning reserve. (Float service for telecommunications and uninterruptible power sources (UPS) applications are not addressed.) Some present and planned installations of valve-regulated lead/acid batteries are surveyed. Performance characteristics will be discussed, including recent results of testing both gel and absorptive glass mat (AGM) types of deep-cycling batteries. Recommendations for future research and development of valve-regulated cell technology are outlined, based on a recent conference organized by the United States Department of Energy (USDOE) and the Electric Power Research Institute (EPRI).

  17. Cleaner environment: removing the barriers to lead-acid battery recycling

    SciTech Connect

    Palmer, J.G.

    1988-12-01

    The author notes that 60% of battery manufacturing lead supplies come from recycled batteries. Without battery recycling, both the availability and the price of lead would radically change business climate of operations. But, the bad news is that, if the lead-acid battery is considered sufficiently harmful to justify closing down the battery recycling industry, what kind of attitude will environmental regulators develop toward the manufacturers of batteries if there is no way to dispose of them. At present, battery recyclers are caught-up in a web of what has come to be known as environmental gridlock, wherein well-intentioned environmental regulations have become so flexible that they actually defeat their original purpose. One example of this condition is the strict, joint and several liability provisions of SUPERFUND. People who collect and transport spent batteries may be held financially responsible for the consequences of circumstances totally beyond their control. Other examples, including excessive hazardous-waste taxes in California, are cited as the author summarizes the environmental gridlock situation. He concludes that, because of the tremendous importance of lead-acid batteries to the American way of life, the real problem is how do we accomplish the goal of recycling 100% of the spent batteries, thereby removing the threat of the spent battery solution.

  18. An eco-balance of a recycling plant for spent lead-acid batteries.

    PubMed

    Salomone, Roberta; Mondello, Fabio; Lanuzza, Francesco; Micali, Giuseppe

    2005-02-01

    This study applies Life Cycle Assessment (LCA) methodology to present an eco-balance of a recycling plant that treats spent lead-acid batteries. The recycling plant uses pyrometallurgical treatment to obtain lead from spent batteries. The application of LCA methodology (ISO 14040 series) enabled us to assess the potential environmental impacts arising from the recycling plant's operations. Thus, net emissions of greenhouse gases as well as other major environmental consequences were examined and hot spots inside the recycling plant were identified. A sensitivity analysis was also performed on certain variables to evaluate their effect on the LCA study. The LCA of a recycling plant for spent lead-acid batteries presented shows that this methodology allows all of the major environmental consequences associated with lead recycling using the pyrometallurgical process to be examined. The study highlights areas in which environmental improvements are easily achievable by a business, providing a basis for suggestions to minimize the environmental impact of its production phases, improving process and company performance in environmental terms.

  19. Associations of uric acid with polymorphisms in the delta-aminolevulinic acid dehydratase, vitamin D receptor, and nitric oxide synthase genes in Korean lead workers.

    PubMed

    Weaver, Virginia M; Schwartz, Brian S; Jaar, Bernard G; Ahn, Kyu-Dong; Todd, Andrew C; Lee, Sung-Soo; Kelsey, Karl T; Silbergeld, Ellen K; Lustberg, Mark E; Parsons, Patrick J; Wen, Jiayu; Lee, Byung-Kook

    2005-11-01

    Recent research suggests that uric acid may be nephrotoxic at lower levels than previously recognized and that it may be one mechanism for lead-related nephrotoxicity. Therefore, in understanding mechanisms for lead-related nephrotoxicity, it would be of value to determine whether genetic polymorphisms that are associated with renal outcomes in lead workers and/or modify associations between lead dose and renal function are also associated with uric acid and/or modify associations between lead dose and uric acid. We analyzed data on three such genetic polymorphisms: delta-aminolevulinic acid dehydratase (ALAD), endothelial nitric oxide synthase (eNOS), and the vitamin D receptor (VDR). Mean (+/- SD) tibia, blood, and dimercaptosuccinic acid-chelatable lead levels were 37.2 +/- 40.4 microg/g bone mineral, 32.0+/- 15.0 g/dL, and 0.77+/- 0.86 microg/mg creatinine, respectively, in 798 current and former lead workers. Participants with the eNOSAsp allele had lower mean serum uric acid compared with those with the Glu/Glu genotype. Among older workers (age > or = median of 40.6 years), ALAD genotype modified associations between lead dose and uric acid levels. Higher lead dose was significantly associated with higher uric acid in workers with the ALAD1-1 genotype; associations were in the opposite direction in participants with the variant ALAD1-2 genotype. In contrast, higher tibia lead was associated with higher uric acid in those with the variant VDRB allele; however, modification was dependent on participants with the bb genotype and high tibia lead levels. We conclude that genetic polymorphisms may modify uric acid mediation of lead-related adverse renal effects.

  20. Inducible Arginase 1 Deficiency in Mice Leads to Hyperargininemia and Altered Amino Acid Metabolism

    PubMed Central

    St. Amand, Tim; Kyriakopoulou, Lianna; Schulze, Andreas; Funk, Colin D.

    2013-01-01

    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 CreERT2 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. PMID:24224027

  1. Field turbidity method for the determination of lead in acid extracts of dried paint.

    PubMed

    Studabaker, William B; McCombs, Michelle; Sorrell, Kristen; Salmons, Cynthia; Brown, G Gordon; Binstock, David; Gutknecht, William F; Harper, Sharon L

    2010-07-08

    Lead, which can be found in old paint, soil, and dust, has been clearly shown to have adverse health effects on the neurological systems of both children and adults. As part of an ongoing effort to reduce childhood lead poisoning, the US Environmental Protection Agency promulgated the Lead Renovation, Repair, and Painting Program (RRP) rule requiring that paint in target housing built prior to 1978 be tested for lead before any renovation, repair, or painting activities are initiated. This rule has led to a need for a rapid, relatively easy, and an inexpensive method for measuring lead in paint. This paper presents a new method for measuring lead extracted from paint that is based on turbidimetry. This method is applicable to paint that has been collected from a surface and extracted into 25% (v/v) of nitric acid. An aliquot of the filtered extract is mixed with an aliquot of solid potassium molybdate in 1 M ammonium acetate to form a turbid suspension of lead molybdate. The lead concentration is determined using a portable turbidity meter. This turbidimetric method has a response of approximately 0.9 NTU per microg lead per mL extract, with a range of 1-1000 Nephelometric Turbidity Units (NTUs). Precision at a concentration corresponding to the EPA-mandated decision point of 1 mg of lead per cm(2) is <2%. This method is insensitive to the presence of other metals common to paint, including Ba(2+), Ca(2+), Mg(2+), Fe(3+), Co(2+), Cu(2+), and Cd(2+), at concentrations of 10 mg mL(-1) or to Zn(2+) at 50 mg mL(-1). Analysis of 14 samples from six reference materials with lead concentrations near 1 mg cm(-2) yielded a correlation to inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analysis of 0.97, with an average bias of 2.8%. Twenty-four sets of either 6 or 10 paint samples each were collected from different locations in old houses, a hospital, tobacco factory, and power station. Half of each set was analyzed using rotor/stator-25% (v/v) nitric acid

  2. Effect modification by delta-aminolevulinic acid dehydratase, vitamin D receptor, and nitric oxide synthase gene polymorphisms on associations between patella lead and renal function in lead workers.

    PubMed

    Weaver, Virginia M; Lee, Byung-Kook; Todd, Andrew C; Ahn, Kyu-Dong; Shi, Weiping; Jaar, Bernard G; Kelsey, Karl T; Lustberg, Mark E; Silbergeld, Ellen K; Parsons, Patrick J; Wen, Jiayu; Schwartz, Brian S

    2006-09-01

    Genetic polymorphisms that affect lead toxicokinetics or toxicodynamics may be important modifiers of risk for adverse outcomes in lead-exposed populations. We recently reported associations between higher patella lead, which is hypothesized to represent a lead pool that is both bioavailable and cumulative, and adverse renal outcomes in current and former Korean lead workers. In the present study, we assessed effect modification by polymorphisms in the genes encoding for delta-aminolevulinic acid dehydratase (ALAD), the vitamin D receptor (VDR), and endothelial nitric oxide synthase on those associations. Similar analyses were conducted with three other lead biomarkers. Renal function was assessed via blood urea nitrogen, serum creatinine, measured and calculated creatinine clearances, urinary N-acetyl-beta-D-glucosaminidase, and retinol-binding protein. Mean (SD) blood, patella, tibia, and dimercaptosuccinic acid-chelatable lead values were 30.9 (16.7) microg/dl, 75.1 (101.1)and 33.6 (43.4) microg Pb/g bone mineral, and 0.63 (0.75) microg Pb/mg creatinine, respectively, in 647 lead workers. Little evidence of effect modification by genotype on associations between patella lead and renal outcomes was observed. The VDR polymorphism did modify associations between the other lead biomarkers and the serum creatinine and calculated creatinine clearance. Higher lead dose was associated with worse renal function in participants with the variant B allele. Models in two groups, dichotomized by median age, showed that this effect was present in the younger half of the population. Limited evidence of effect modification by ALAD genotype was observed; higher blood lead levels were associated with higher calculated creatinine clearance among participants with the ALAD(1-2) genotype. In conclusion, VDR and/or ALAD genotypes modified associations between all the lead biomarkers, except patella lead, and the renal outcomes.

  3. Lead-acid bipolar battery assembled with primary chemically formed positive pasted electrode

    NASA Astrophysics Data System (ADS)

    Karami, H.; Shamsipur, M.; Ghasemi, S.; Mousavi, M. F.

    Primary chemically formed lead dioxide (PbO 2) was used as positive electrode in preparation of lead-acid bipolar batteries. Chemical oxidation was carried out by both mixing and dipping methods using an optimized amount of ammonium persulfate as a suitable oxidizing agent. X-ray diffraction studies showed that the weight ratio of β-PbO 2 to α-PbO 2 is more for mixing method before electrochemical forming. The electrochemical impedance spectroscopy (EIS) was used to investigate charge transfer resistance of the lead dioxide obtained by mixing and dipping methods before and after electrochemical forming. Four types of bipolar lead-acid batteries were produced with: (1) lead substrate and conventional electroforming; (2) carbon doped polyethylene substrate with conventional electroforming; (3) carbon doped polyethylene substrate with chemical forming after curing and drying steps in oxidant bath, followed by electrochemical forming, and (4) carbon doped polyethylene substrate with primary chemical oxidation in mixing step, followed by conventional electroforming. The capacity and cycle-life tests of the prepared bipolar batteries were performed by a home-made battery tester and using the pulsed current method. The prepared batteries showed low weight, high capacity, high energy density and high power density. The first capacities of bipolar batteries of type 1-4 were found to be 152, 150, 180 and 198 mAh g -1, respectively. The experimental results showed that the prepared 6 V bipolar batteries of type 1-4 have power density (per cell unit) of 59.7, 57.4, 78.46 and 83.30 mW g -1 (W kg -1), respectively.

  4. An analytical study of a lead-acid flow battery as an energy storage system

    NASA Astrophysics Data System (ADS)

    Bates, Alex; Mukerjee, Santanu; Lee, Sang C.; Lee, Dong-Ha; Park, Sam

    2014-03-01

    The most important issue with our current clean energy technology is the dependence on environmental conditions to produce power. To solve this problem a wide range of energy storage devices are being explored for grid-scale energy storage including soluble lead-acid flow batteries. Flow batteries offer a unique solution to grid-scale energy storage because of their electrolyte tanks which allow easy scaling of storage capacity. This study seeks to further understand the mechanisms of a soluble lead acid flow battery using simulations. The effects of varies changes to operating conditions and the system configuration can be explored through simulations. The simulations preformed are 2D and include the positive electrode, negative electrode, and the flow space between them. Simulations presented in this study show Pb(II) surface concentration, external electric potential, and PbO/PbO2 surface concentration on the positive electrode. Simulations have shown increasing cell temperature can increase external electric potential by as much as 0.2 V during charge. Simulations have also shown electrolyte velocity is an important aspect when investigating lead deposition onto the electrodes. Experimental work was performed to validate simulation results of current density and voltage. Good correlation was found between experimental work and simulation results.

  5. Poly(acrylic acid) modifying bentonite with in-situ polymerization for removing lead ions.

    PubMed

    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%).

  6. Effect of plate preparation on active-material utilization and cycleability of positive plates in automotive lead/acid batteries

    NASA Astrophysics Data System (ADS)

    Ozgun, H.; Lam, L. T.; Rand, D. A. J.; Bhargava, S. K.

    The power demands from automotive lead/acid batteries are rising steadily with the increasing number of electronic accessories that are being fitted to modern vehicles. In order to meet new levels of performance, automotive batteries have been redesigned to use low-ohmic microporous separators, as well as thinner plates (to increase the number of plates per cell) that are made with a low paste density. This approach, however, has led to a separate problem, namely, an appreciable reduction in battery service life. To redress this situation, a research programme has been implemented in our laboratories to examine, in detail, the effect of plate preparation on the active-material utilization and cycleability of automotive positive plates with grids made from low-antimony alloy. The cycleability is evaluated in terms of repetitive reserve-capacity. The results suggest that a paste formula with a combination of high density and low acid-to-oxide ratio is the most appropriate technology for the production of the thin positive plates that are required in advanced designs of automotive batteries.

  7. Dental erosion in workers exposed to sulfuric acid in lead storage battery manufacturing facility.

    PubMed

    Suyama, Yuji; Takaku, Satoru; Okawa, Yoshikazu; Matsukubo, Takashi

    2010-01-01

    Dental erosion, and specifically its symptoms, has long been studied in Japan as an occupational dental disease. However, in recent years, few studies have investigated the development of this disease or labor hygiene management aimed at its prevention. As a result, interest in dental erosion is comparatively low, even among dental professionals. Our investigation at a lead storage battery factory in 1991 found that the work environmental sulfuric acid density was above the tolerable range (1.0mg/m(3)) and that longterm workers had dental erosion. Therefore, workers handling sulfuric acid were given an oral examination and rates of dental erosion by tooth type, rates of erosion by number of working years and rates of erosion by sulfuric acid density in the work environment investigated. Where dental erosion was diagnosed, degree of erosion was identified according to a diagnostic criterion. No development of dental erosion was detected in the maxillary teeth, and erosion was concentrated in the anterior mandibular teeth. Its prevalence was as high as 20%. Rates of dental erosion rose precipitously after 10 working years. The percentages of workers with dental erosion were 42.9% for 10-14 years, 57.1% for 15-19 years and 66.7% for over 20 years with 22.5% for total number of workers. The percentages of workers with dental erosion rose in proportion to work environmental sulfuric acid density: 17.9% at 0.5-1.0, 25.0% at 1.0-4.0 and 50.0% at 4.0-8.0mg/m(3). This suggests that it is necessary to evaluate not only years of exposure to sulfuric acid but also sulfuric acid density in the air in factory workers.

  8. CHR-2797: an antiproliferative aminopeptidase inhibitor that leads to amino acid deprivation in human leukemic cells.

    PubMed

    Krige, David; Needham, Lindsey A; Bawden, Lindsay J; Flores, Nicolas; Farmer, Hannah; Miles, Lauren E C; Stone, Erica; Callaghan, Juliana; Chandler, Stephen; Clark, Vanessa L; Kirwin-Jones, Patricia; Legris, Valérie; Owen, Jo; Patel, Thakor; Wood, Steve; Box, Gary; Laber, David; Odedra, Rajesh; Wright, Annette; Wood, L Michael; Eccles, Suzanne A; Bone, Elisabeth A; Ayscough, Andrew; Drummond, Alan H

    2008-08-15

    CHR-2797 is a novel metalloenzyme inhibitor that is converted into a pharmacologically active acid product (CHR-79888) inside cells. CHR-79888 is a potent inhibitor of a number of intracellular aminopeptidases, including leucine aminopeptidase. CHR-2797 exerts antiproliferative effects against a range of tumor cell lines in vitro and in vivo and shows selectivity for transformed over nontransformed cells. Its antiproliferative effects are at least 300 times more potent than the prototypical aminopeptidase inhibitor, bestatin. However, the mechanism by which inhibition of these enzymes leads to proliferative changes is not understood. Gene expression microarrays were used to profile changes in mRNA expression levels in the human promyelocytic leukemia cell line HL-60 treated with CHR-2797. This analysis showed that CHR-2797 treatment induced a transcriptional response indicative of amino acid depletion, the amino acid deprivation response, which involves up-regulation of amino acid synthetic genes, transporters, and tRNA synthetases. These changes were confirmed in other leukemic cell lines sensitive to the antiproliferative effects of CHR-2797. Furthermore, CHR-2797 treatment inhibited phosphorylation of mTOR substrates and reduced protein synthesis in HL-60 cells, both also indicative of amino acid depletion. Treatment with CHR-2797 led to an increase in the concentration of intracellular small peptides, the substrates of aminopeptidases. It is suggested that aminopeptidase inhibitors, such as CHR-2797 and bestatin, deplete sensitive tumor cells of amino acids by blocking protein recycling, and this generates an antiproliferative effect. CHR-2797 is orally bioavailable and currently undergoing phase II clinical investigation in the treatment of myeloid leukemia.

  9. Degradation of Opioids and Opiates During Acid Hydrolysis Leads to Reduced Recovery Compared to Enzymatic Hydrolysis.

    PubMed

    Sitasuwan, Pongkwan; Melendez, Cathleen; Marinova, Margarita; Mastrianni, Kaylee R; Darragh, Alicia; Ryan, Emily; Lee, L Andrew

    2016-10-01

    Drug monitoring laboratories utilize a hydrolysis process to liberate the opiates from their glucuronide conjugates to facilitate their detection by tandem mass spectrometry (MS). Both acid and enzyme hydrolysis have been reported as viable methods, with the former as a more effective process for recovering codeine-6-glucuronide and morphine-6-glucuronide. Here, we report concerns with acid-catalyzed hydrolysis of opioids, including a significant loss of analytes and conversions of oxycodone to oxymorphone, hydrocodone to hydromorphone and codeine to morphine. The acid-catalyzed reaction was monitored in neat water and patient urine samples by liquid chromatography-time-of-flight and tandem MS. These side reactions with acid hydrolysis may limit accurate quantitation due to loss of analytes, possibly lead to false positives, and poorly correlate with pharmacogenetic profiles, as cytochrome P450 enzyme (CYP2D6) is often involved with oxycodone to oxymorphone, hydrocodone to hydromorphone and codeine to morphine conversions. Enzymatic hydrolysis process using the purified, genetically engineered β-glucuronidase (IMCSzyme(®)) addresses many of these concerns and demonstrates accurate quantitation and high recoveries for oxycodone, hydrocodone, oxymorphone and hydromorphone.

  10. Design of an efficient electrolyte circulation system for the lead-acid battery

    NASA Astrophysics Data System (ADS)

    Thuerk, D.

    The design and operation of an electrolyte circulation system are described. Application of lead acid batteries to electric vehicle and other repetitive deep cycle services produces a nondesirable state in the battery cells, electrolyte stratification. This stratification is the result of acid and water generation at the electrodes during cycling. With continued cycling, the extent of the stratification increases and prevents complete charging with low percentages of overcharge. Ultimately this results in extremely short life for the battery system. The stratification problem was overcome by substantially overcharging the battery. This abusive overcharge produces gassing rates sufficient to mix the electrolyte during the end portion of the charge. Overcharge, even though it is required to eliminate stratification, produces the undesirable results related to high voltage and gassing rates.

  11. Lead-acid batteries for micro- and mild-hybrid applications

    NASA Astrophysics Data System (ADS)

    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.

  12. [Comparison and application of two risk assessment methods for occupational lead exposure risk classification in a lead-acid battery enterprise].

    PubMed

    Chen, H F; Yao, Z H; Yan, X H; Zhao, L; Wang, S; Lin, J; Huang, H L

    2017-02-20

    Objective: To apply and compare two risk assessment methods for occupational lead exposure risk classification in a lead-acid battery enterprise. Methods: In April 2013, an occupational health survey was carried out in a lead-acid battery enterprise. Lead smoke and lead dust were tested in the workplace. The risk assessment index system for occupational chemical hazards that was established and optimized by the research group (referred to as "optimized index system" ) , as well as the Singapore semi-quantitative risk assessment model, was used for occupational lead exposure risk classification in the lead-acid battery enterprise. The two risk classification results were analyzed and compared. Results: In the lead smoke risk classification results, the optimized index system classified the raw material group and foundry group workshops as Class I hazardous and the assembling group workshop as Class II hazardous. The Singapore semi-quantitative risk assessment model classified the raw material group workshop as high risk and foundry group and assembling group workshops as extremely high risk. In the lead dust risk classification results, the optimized index system classified the raw material group workshop as Class I hazardous, while the plate painting group, plate cutting group, and assembling group workshops were classified as Class II hazardous. The Singapore semi-quantitative risk assessment model classified the raw material group workshop as medium risk, the plate painting group and plate cutting group workshops as high risk, and the assembling group workshop as extremely high risk. Conclusion: There are some differences in risk assessment of occupational lead exposure between the two risk assessment methods. The optimized index system is comparably more reasonable and feasible, and is highly operable.

  13. Silver-silver sulfate reference electrodes for use in lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Ruetschi, Paul

    Electrochemical properties of silver-silver sulfate reference electrodes for lead-acid batteries are described, and the following possible applications discussed: Determination of individual capacities of positive and negative plates. Monitoring individual electrode behavior during deep discharge and cell reversal. Optimization charge or discharge parameters, by controlling the current such that pre-determined limits of positive or negative half-cell potential are respected. Observation of acid concentration differences, for example due to acid stratification, by measuring diffusion potentials (concentration-cell voltages). Detection of defective cells, and defective plate sets, in a string of cells, at the end of their service life. Silver-silver sulfate reference electrodes, permanently installed in lead-acid cells, may be a means to improve battery management, and therewith to improve reliability and service life. In vented batteries, reference electrodes may be used to limit positive plate polarization during charge, or float-charge. Limiting the positive half-cell potential to an upper, pre-set value would permit to keep anodic corrosion as low as possible. During cycling, discharge could be terminated when the half-cell potential of the positive electrode has dropped to a pre-set limit. This would prevent excessive discharge of the positive electrodes, which could result in an improvement of cycle life. In valve-regulated batteries, reference electrodes may be used to adjust float-charge conditions such as to assure sufficient cathodic polarization of the negative electrodes, in order to avoid sulfation. The use of such reference electrodes could be beneficial particularly in multi-cell batteries, with overall voltages above 12 V, operated in a partial-state-of-charge.

  14. Chopper-controlled discharge life cycling studies on lead-acid batteries

    NASA Technical Reports Server (NTRS)

    Kraml, J. J.; Ames, E. P.

    1982-01-01

    State-of-the-art 6 volt lead-acid golf car batteries were tested. A daily charge/discharge cycling to failure points under various chopper controlled pulsed dc and continuous current load conditions was undertaken. The cycle life and failure modes were investigated for depth of discharge, average current chopper frequency, and chopper duty cycle. It is shown that battery life is primarily and inversely related to depth of discharge and discharge current. Failure mode is characterized by a gradual capacity loss with consistent evidence of cell element aging.

  15. Optical State-of-Change Monitor for Lead-Acid Batteries

    SciTech Connect

    Weiss, Jonathan D.

    1998-07-24

    A method and apparatus for determining the instantaneous state-of-charge of a battery in which change in composition with discharge manifests itself as a change in optical absorption. In a lead-acid battery, the sensor comprises a fiber optic system with an absorption cdl or, alternatively, an optical fiber woven into an absorbed-glass-mat battery. In a lithium-ion battery, the sensor comprises fiber optics for introducing light into the anode to monitor absorption when lithium ions are introduced.

  16. Novel charge/discharge method for lead acid battery by high-pressure crystallization

    NASA Astrophysics Data System (ADS)

    Arakawa, Naoko; Maeda, Kouji; Moritoki, Masato; Fukui, Keisuke; Kuramochi, Hidetoshi; Miki, Hideo

    2013-06-01

    The electrical charging and discharging of a battery involves the crystallization of electrolytes or metal oxides on both electrodes. Crystallization technology that can control nucleation, growth, and distribution of solute crystals might be effective for improving battery properties. We performed charge/discharge cycling of a lead acid battery under high pressure. The charging efficiency at high pressure was compared with that at atmospheric pressure. Charging efficiency at high pressure was found to be higher than that at atmospheric pressure under a high charging current. Observation of the positive electrode by scanning electron microscopy revealed that high pressure caused the crystals on the electrode to become extremely fine.

  17. Distribution of current in the electrodes of lead-acid batteries: a thermographic analysis approach

    NASA Astrophysics Data System (ADS)

    Streza, M.; Nuţ, C.; Tudoran, C.; Bunea, V.; Calborean, A.; Morari, C.

    2016-02-01

    An experimental method for the investigation of the current distribution in the electrodes of lead-acid batteries has been developed. The information is extracted by analysing the heat dissipation in the electrode during the discharge by using a high-performance IR camera. The effect of the current in the metallic grid can be de-convoluted from the total heat produced in the electrode by numerical processing of the temperature distribution over the electrode surface. By its simplicity and effectiveness, the proposed method has the potential to become an important tool in optimising electrode geometry.

  18. Development of 36-V valve-regulated lead-acid battery

    NASA Astrophysics Data System (ADS)

    Ohmae, T.; Hayashi, T.; Inoue, N.

    A 36-V valve-regulated lead-acid (VRLA) battery used in a 42-V power system has been developed for the Toyota Hybrid System-Mild (THS-M) vehicle to meet the large electrical power requirements of hybrid electric vehicles (HEVs) and the increasing power demands on modern automobile electrical systems. The battery has a longer cycle-life in HEV use through the application of ultra high-density active-material and an anti-corrosive grid alloy for the positive plates, special additives for the negative plates, and absorbent glass mat with less contraction for the separators.

  19. A new lead-acid battery for high pulse power applications

    NASA Technical Reports Server (NTRS)

    Rowlette, J. J.; Attia, A. I.

    1987-01-01

    The development of new electronically conductive materials which can withstand the environment of the positive plates has made possible the construction of a high pulse power sealed bipolar lead-acid battery. The new battery is described and its advantages over other electrochemical systems are outlined. Performance projections show that the peak specific power of the battery can be as high as 90 kW/kg, and that a specific power of 5 kW/kg can be sustained over several thousand pulses.

  20. Real-time estimation of lead-acid battery parameters: A dynamic data-driven approach

    NASA Astrophysics Data System (ADS)

    Li, Yue; Shen, Zheng; Ray, Asok; Rahn, Christopher D.

    2014-12-01

    This short paper presents a recently reported dynamic data-driven method, Symbolic Dynamic Filtering (SDF), for real-time estimation of the state-of-health (SOH) and state-of-charge (SOC) in lead-acid batteries, as an alternative to model-based analysis techniques. In particular, SOC estimation relies on a k-NN regression algorithm while SOH estimation is obtained from the divergence between extracted features. The results show that the proposed data-driven method successfully distinguishes battery voltage responses under different SOC and SOH situations.

  1. An averaging battery model for a lead-acid battery operating in an electric car

    NASA Technical Reports Server (NTRS)

    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.

  2. Reliability of valve-regulated lead-acid batteries for stationary applications.

    SciTech Connect

    De Anda, Mindi Farber; Butler, Paul Charles; Miller, Jennifer L; Moseley, Patrick T.

    2004-03-01

    A survey has been carried out to quantify the performance and life of over 700,000 valve-regulated lead-acid (VRLA) cells, which have been or are being used in stationary applications across the United States. The findings derived from this study have not identified any fundamental flaws of VRLA battery technology. There is evidence that some cell designs are more successful in float duty than others. A significant number of the VRLA cells covered by the survey were found to have provided satisfactory performance.

  3. Results of chopper-controlled discharge life cycling studies on lead acid batteries

    NASA Technical Reports Server (NTRS)

    Ewashinka, J. G.; Sidik, S. M.

    1982-01-01

    A group of 108 state of the art nominally 6 volt lead acid batteries were tested in a program of one charge/discharge cycle per day for over two years or to ultimate battery failure. The primary objective was to determine battery cycle life as a function of depth of discharge (25 to 75 percent), chopper frequency (100 to 1000 Hz), duty cycle (25 to 87.5 percent), and average discharge current (20 to 260 A). The secondary objective was to determine the types of battery failure modes, if any, were due to the above parameters. The four parameters above were incorporated in a statistically designed test program.

  4. The sealed lead-acid battery: performance and present aircraft applications

    NASA Astrophysics Data System (ADS)

    Timmons, John; Kurian, Raju; Goodman, Alan; Johnson, William R.

    The United States Navy has flown valve-regulated lead-acid batteries (VRLA) for approximately 22 years. The first VRLA aircraft batteries were of a cylindrical cell design and these evolved to a prismatic design to save weight, volume, and to increase rate capability. This paper discusses the evolution of the VRLA aircraft battery designs, present VRLA battery performance, and battery size availability along with their aircraft applications (both military and commercial). The paper provides some of the reliability data from present applications. Finally, the paper discusses what future evolution of the VRLA technology is required to improve performance and to remain the technology of choice over other sealed aircraft battery designs.

  5. A cerium-lead redox flow battery system employing supporting electrolyte of methanesulfonic acid

    NASA Astrophysics Data System (ADS)

    Na, Zhaolin; Xu, Shengnan; Yin, Dongming; Wang, Limin

    2015-11-01

    A novel cerium-lead redox flow battery (RFB) employing Ce(IV)/Ce(III) and Pb(II)/Pb redox couples in the supporting electrolyte of methanesulfonic acid (MSA) is developed and preliminarily investigated. The RFB requires no additional catalyst and uses kinetically favorable reactions between low-cost reactants, and provides a desirable discharge voltage of approximately 1.7 V, with high average coulombic efficiency (CE) of 92% and energy efficiency (EE) of 86% over 800 cycles at 298 K. Stable cycling with an acceptable performance is achieved for a board operating temperature range of 253 K-313 K. The excellent performance obtained from the preliminary study suggests that the cerium-lead RFB promises to be applicable to large-scale energy storage for electricity grids.

  6. Acid rain and its environmental effects: Recent scientific advances

    NASA Astrophysics Data System (ADS)

    Burns, Douglas A.; Aherne, Julian; Gay, David A.; Lehmann, Christopher M. B.

    2016-12-01

    The term 'acid rain' refers to atmospheric deposition of acidic constituents that impact the earth as rain, snow, particulates, gases, and vapor. Acid rain was first recognized by Ducros (1845) and subsequently described by the English chemist Robert Angus Smith (Smith, 1852) whose pioneering studies linked the sources to industrial emissions and included early observations of deleterious environmental effects (Smith, 1872). Smith's work was largely forgotten until the mid-20th century when observations began to link air pollution to the deposition of atmospheric sulfate (SO42-) and other chemical constituents, first near the metal smelter at Sudbury, Ontario, Canada, and later at locations in Europe, North America, and Australia (Gorham, 1961). Our modern understanding of acid rain as an environmental problem caused largely by regional emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) stems from observations in the 1960s and early 1970s in Sweden by Svante Odén (Odén, 1976), and in North America by Gene Likens and colleagues (Likens and Bormann, 1974). These scientists and many who followed showed the link to emissions from coal-fired power plants and other industrial sources, and documented the environmental effects of acid rain such as the acidification of surface waters and toxic effects on vegetation, fish, and other biota.

  7. Acid rain and its environmental effects: Recent scientific advances

    USGS Publications Warehouse

    Burns, Douglas A.; Aherne, Julian; Gay, David A.; Lehmann, Christopher M.B.

    2016-01-01

    The term ‘acid rain’ refers to atmospheric deposition of acidic constituents that impact the earth as rain, snow, particulates, gases, and vapor. Acid rain was first recognized by Ducros (1845) and subsequently described by the English chemist Robert Angus Smith (Smith, 1852) whose pioneering studies linked the sources to industrial emissions and included early observations of deleterious environmental effects (Smith, 1872). Smith's work was largely forgotten until the mid-20th century when observations began to link air pollution to the deposition of atmospheric sulfate (SO42−) and other chemical constituents, first near the metal smelter at Sudbury, Ontario, Canada, and later at locations in Europe, North America, and Australia (Gorham, 1961). Our modern understanding of acid rain as an environmental problem caused largely by regional emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) stems from observations in the 1960s and early 1970s in Sweden by Svante Odén (Odén, 1976), and in North America by Gene Likens and colleagues (Likens and Bormann, 1974). These scientists and many who followed showed the link to emissions from coal-fired power plants and other industrial sources, and documented the environmental effects of acid rain such as the acidification of surface waters and toxic effects on vegetation, fish, and other biota.

  8. Case study: technology initiative led to advanced lead optimization screening processes at Bristol-Myers Squibb, 2004-2009.

    PubMed

    Zhang, Litao; Cvijic, Mary Ellen; Lippy, Jonathan; Myslik, James; Brenner, Stephen L; Binnie, Alastair; Houston, John G

    2012-07-01

    In this paper, we review the key solutions that enabled evolution of the lead optimization screening support process at Bristol-Myers Squibb (BMS) between 2004 and 2009. During this time, technology infrastructure investment and scientific expertise integration laid the foundations to build and tailor lead optimization screening support models across all therapeutic groups at BMS. Together, harnessing advanced screening technology platforms and expanding panel screening strategy led to a paradigm shift at BMS in supporting lead optimization screening capability. Parallel SAR and structure liability relationship (SLR) screening approaches were first and broadly introduced to empower more-rapid and -informed decisions about chemical synthesis strategy and to broaden options for identifying high-quality drug candidates during lead optimization.

  9. Leaching of lead from zinc leach residue in acidic calcium chloride aqueous solution

    NASA Astrophysics Data System (ADS)

    Wang, Le; Mu, Wen-ning; Shen, Hong-tao; Liu, Shao-ming; Zhai, Yu-chun

    2015-05-01

    A process with potentially reduced environmental impacts and occupational hazards of lead-bearing zinc plant residue was studied to achieve a higher recovery of lead via a cost-effective and environmentally friendly process. This paper describes an optimization study on the leaching of lead from zinc leach residue using acidic calcium chloride aqueous solution. Six main process conditions, i.e., the solution pH value, stirring rate, concentration of CaCl2 aqueous solution, liquid-to-solid (L/S) ratio, leaching temperature, and leaching time, were investigated. The microstructure and components of the residue and tailing were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). On the basis of experimental results, the optimum reaction conditions were determined to be a solution pH value of 1, a stirring rate of 500 r·min-1, a CaCl2 aqueous solution concentration of 400 g·L-1, a liquid-to-solid mass ratio of 7:1, a leaching temperature of 80°C, and a leaching time of 45 min. The leaching rate of lead under these conditions reached 93.79%, with an iron dissolution rate of 19.28%. Silica did not take part in the chemical reaction during the leaching process and was accumulated in the residue.

  10. δ-Aminolevulinic acid dehydrase activity in the blood of men working with lead alkyls

    PubMed Central

    Millar, J. A.; Thompson, G. G.; Goldberg, A.; Barry, P. S. I.; Lowe, E. H.

    1972-01-01

    Millar, J. A., Thompson, G. G., Goldberg, A., Barry, P. S. I., and Lowe, E. H. (1972).Brit. J. industr. Med.,29, 317-320. δ-Aminolevulinic acid dehydrase activity in the blood of men working with lead alkyls. The activity of erythrocyte ALA1-dehydrase is inhibited in vivo at blood lead (Pb2+) levels within the upper range of normal (20-40 μg/100 ml) and in vitro at lead concentrations greater than 10-7 M. In view of the high sensitivity of the enzyme to Pb2+, the levels of enzyme activity in the blood of men occupationally exposed to lead alkyls, particularly tetraethyllead, were measured. It was found that the enzyme activity in an exposed group of men was significantly less (P<0·001) than in a control group, the respective mean values being 220 and 677 units of enzyme activity. Tetraethyllead is metabolized in the body via triethyllead and diethyllead ions. As the latter compound possesses properties similar to Pb2+, it was synthesized in the laboratory and its effect on ALA-dehydrase was studied. Diethyllead ion was found to inhibit ALA-dehydrase activity at concentrations greater than 5 x 10-5 M, although the degree of inhibition was less than that obtained with Pb2+. These results suggest that exposure to tetraethyllead can cause a decrease in erythrocyte ALA-dehydrase activity. PMID:5044603

  11. Rapid dissolution of ZnO nanocrystals in acidic cancer microenvironment leading to preferential apoptosis

    NASA Astrophysics Data System (ADS)

    Sasidharan, Abhilash; Chandran, Parwathy; Menon, Deepthy; Raman, Sreerekha; Nair, Shantikumar; Koyakutty, Manzoor

    2011-09-01

    The microenvironment of cancer plays a very critical role in the survival, proliferation and drug resistance of solid tumors. Here, we report an interesting, acidic cancer microenvironment-mediated dissolution-induced preferential toxicity of ZnO nanocrystals (NCs) against cancer cells while leaving primary cells unaffected. Irrespective of the size-scale (5 and 200 nm) and surface chemistry differences (silica, starch or polyethylene glycol coating), ZnO NCs exhibited multiple stress mechanisms against cancer cell lines (IC50 ~150 μM) while normal human primary cells (human dermal fibroblast, lymphocytes, human umbilical vein endothelial cells) remain less affected. Flow cytometry and confocal microscopy studies revealed that ZnO NCs undergo rapid preferential dissolution in acidic (pH ~5-6) cancer microenvironment causing elevated ROS stress, mitochondrial superoxide formation, depolarization of mitochondrial membrane, and cell cycle arrest at S/G2 phase leading to apoptosis. In effect, by elucidating the unique toxicity mechanism of ZnO NCs, we show that ZnO NCs can destabilize cancer cells by utilizing its own hostile acidic microenvironment, which is otherwise critical for its survival.The microenvironment of cancer plays a very critical role in the survival, proliferation and drug resistance of solid tumors. Here, we report an interesting, acidic cancer microenvironment-mediated dissolution-induced preferential toxicity of ZnO nanocrystals (NCs) against cancer cells while leaving primary cells unaffected. Irrespective of the size-scale (5 and 200 nm) and surface chemistry differences (silica, starch or polyethylene glycol coating), ZnO NCs exhibited multiple stress mechanisms against cancer cell lines (IC50 ~150 μM) while normal human primary cells (human dermal fibroblast, lymphocytes, human umbilical vein endothelial cells) remain less affected. Flow cytometry and confocal microscopy studies revealed that ZnO NCs undergo rapid preferential dissolution in

  12. Transforming Tech Ed: The Advanced Technological Education Community Leads in Developing and Implementing Teaching Strategies

    ERIC Educational Resources Information Center

    Patton, Madeline

    2015-01-01

    After years of working in the background to build the capacity of two-year college science, technology, engineering and math (STEM) faculty and the skills of technicians, the Advanced Technological Education (ATE) program is gaining recognition as a source of STEM workforce expertise. The ATE program's effective mentoring of STEM educators and its…

  13. 24 CFR 242.48 - Insured advances for certain equipment and long lead items.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... necessary to meet the requirements of the overall construction schedule cited in the construction contract. ... HOUSING ACT AND OTHER AUTHORITIES MORTGAGE INSURANCE FOR HOSPITALS Construction § 242.48 Insured advances... equipment or other construction materials for which a manufacturer, fabricator, or other source requires...

  14. [Molluscacide activity of a mixture of 6-n-alkyl salicylic acids (anacardic acid) and 2 of its complexes with copper (II) and lead (II)].

    PubMed

    Mendes, N M; de Oliveira, A B; Guimarães, J E; Pereira, J P; Katz, N

    1990-01-01

    The molluscicide activity of hexanic extract from Anacardium occidentale L. (cashew) nut shell, of copper (II) complex, of lead (II) complex and anacardic acid has been compared in the laboratory in an attempt to obtain better stability than anacardic acid. This was obtained from the hexanic extract of the cashew nut shell by precipitation with lead (II) hydroxide or cupric sulfate plus sodium hydroxide or (II) cupric hydroxide followed by treatment of lead (II) complex with a diluted solution of sulfuric acid. Ten products of the mixture obtained were tested on adults snails of Biomphalaria glabrata at 1 to 10 ppm. The most active products were copper (II) complex, obtained by cupric sulfate plus sodium hydroxide, and anacardic acid (sodium hydroxide) which presented activity at 4 ppm. The anacardic acid's lead content was above the limits accepted by the United States standards.

  15. Valve-regulated lead-acid batteries for stop-and-go applications

    NASA Astrophysics Data System (ADS)

    May, G. J.

    Increasing levels of demand for electrical power for vehicles have prompted a considerable level of research into higher voltage systems. This has resulted in the definition of preliminary standards for 36/42 V systems. The implementation costs for these systems are high and this has led to improvements in 12/14 V power architectures. In particular, alternator power outputs at 14 V have increased and the need for lower emission levels and fuel economy is stimulating a demand for stop-and-go systems. In this type of application, the engine is stopped each time the vehicle comes to a halt, and is restarted when the accelerator is pressed again. The duty cycle that this applies to the battery is quite onerous with many shallow discharge cycles. Flooded lead-acid batteries are unable to meet the requirements and valve-regulated lead-acid (VRLA) batteries are essential to meet the demands applied. The background to stop-and-go battery applications is considered and test results on practical batteries are presented to show that under a simulated duty cycle, good performance can be achieved. There is also a need for a higher level of battery management for stop-and-go systems. A practical approach to battery condition monitoring to assess the state-of-charge and state-of-health of the battery is described.

  16. Effect of discharge rate on charging a lead-acid battery simulated by mathematical model

    NASA Astrophysics Data System (ADS)

    Cugnet, Mikael; Liaw, Bor Yann

    To simulate lead-acid battery (LAB) charging has never been an easy task due to the influences of: (1) secondary reactions that involve gas evolution and recombination and grid corrosion, (2) prior end-of-discharge (EOD) and rest conditions; and (3) complexity caused by charging algorithm. In this work, successful results have been obtained with considerations of internal oxygen cycle and gas phase in the valve-regulated lead-acid (VRLA) cells. The success is first attributed to the satisfactory validation of a mathematical model that has been able to simulate discharge regimes with various rates consistently. The model has been subsequently used to simulate a galvanostatic charge regime performed at C/10. The results give a better understanding of the role each electrode played in the polarization, the nature of the polarization (constituted by reaction kinetics and mass transport), and the charging efficiency. We were able to extrapolate the simulation results to rates beyond what the model has been validated for, and the results are still consistent, confirming some experimental observations, notably the maximum charging rate specified by most LAB manufacturers.

  17. High-performance of PbO2 nanowire electrodes for lead-acid battery

    NASA Astrophysics Data System (ADS)

    Moncada, A.; Mistretta, M. C.; Randazzo, S.; Piazza, S.; Sunseri, C.; Inguanta, R.

    2014-06-01

    PbO2 nanowires were obtained by template electrodeposition in polycarbonate membranes and tested as positive electrode for lead-acid battery. Nanowires were grown on the same material acting as current collector that was electrodeposited too. The nanostructured electrodes were assembled in a zero-gap configuration using commercial negative plate and separator. Cell performance was tested by galvanostatic charge/discharge cycles in a 5 M H2SO4 aqueous electrolyte. PbO2 nanostructured electrodes were able to deliver at 1C rate an almost constant capacity of about 190 mAh g-1 (85% of active material utilization), close to the theoretical value (224 mAh g-1). The nanowire array provides a very large surface area (about 70 times higher than the geometrical one) that enhances the specific capacity of the battery. SEM images of the as-prepared and cycled electrodes showed that nanowires morphology changes significantly after the initial cycles. Change of morphology led to the formation of very spongy structure, characterized by the presence of macro-voids, which ensured penetration of the electrolyte in the inner areas of the electrode. Besides, PbO2 nanowires showed a very good cycling stability, maintained for more than 1000 cycles. These findings indicate that this new type of electrode might be a promising substitute of positive plates in lead-acid battery.

  18. Developments in absorptive glass mat separators for cycling applications and 36 V lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Toniazzo, V.; Lambert, U.

    The major markets for valve-regulated lead-acid (VRLA) batteries are undergoing a radical upheaval. In particular, the telecommunications industry requires more reliable power supplies, and the familiar 12 V electrical system in cars will probably be soon replaced by a 36/42 V system, or by other electrical systems if part of the automotive market is taken over by hybrid electrical vehicles (HEVs). In order to meet these new challenges and enable VRLA batteries to provide a satisfactory life in float and cycling applications in the telecommunication field, or in the high-rate-partial-state-of-charge service required by both 36/42 V automobiles and HEVs, the lead-acid battery industry has to improve substantially the quality of present VRLA batteries based on absorptive glass mat (AGM) technology. Therefore, manufacturing steps and cell components have to be optimized, especially AGM separators as these are key components for better production yields and battery performance. This paper shows how the optimal segregation of the coarse and fine fibres in an AGM separator structure can improve greatly the properties of the material. The superior capillarity, springiness and mechanical properties of the 100% glass Amerglass multilayer separator compared with commercial monolayer counterparts with the same specific surface-area is highlighted.

  19. Lead-free Organic-Inorganic Hybrid Perovskites for Photovoltaic Applications: Recent Advances and Perspectives.

    PubMed

    Shi, Zejiao; Guo, Jia; Chen, Yonghua; Li, Qi; Pan, Yufeng; Zhang, Haijuan; Xia, Yingdong; Huang, Wei

    2017-02-03

    Organic-inorganic hybrid halide perovskites (e.g., MAPbI3 ) have recently emerged as novel active materials for photovoltaic applications with power conversion efficiency over 22%. Conventional perovskite solar cells (PSCs); however, suffer the issue that lead is toxic to the environment and organisms for a long time and is hard to excrete from the body. Therefore, it is imperative to find environmentally-friendly metal ions to replace lead for the further development of PSCs. Previous work has demonstrated that Sn, Ge, Cu, Bi, and Sb ions could be used as alternative ions in perovskite configurations to form a new environmentally-friendly lead-free perovskite structure. Here, we review recent progress on lead-free PSCs in terms of the theoretical insight and experimental explorations of the crystal structure of lead-free perovskite, thin film deposition, and device performance. We also discuss the importance of obtaining further understanding of the fundamental properties of lead-free hybrid perovskites, especially those related to photophysics.

  20. Lead-acid batteries in micro-hybrid applications. Part I. Selected key parameters

    NASA Astrophysics Data System (ADS)

    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.

  1. Current advances in biological production of propionic acid.

    PubMed

    Eş, Ismail; Khaneghah, Amin Mousavi; Hashemi, Seyed Mohammad Bagher; Koubaa, Mohamed

    2017-02-01

    Propionic acid and its derivatives are considered "Generally Recognized As Safe" food additives and are generally used as an anti-microbial and anti-inflammatory agent, herbicide, and artificial flavor in diverse industrial applications. It is produced via biological pathways using Propionibacterium and some anaerobic bacteria. However, its commercial chemical synthesis from the petroleum-based feedstock is the conventional production process bit results in some environmental issues. Novel biological approaches using microorganisms and renewable biomass have attracted considerable recent attention due to economic advantages as well as great adaptation with the green technology. This review provides a comprehensive overview of important biotechnological aspects of propionic acid production using recent technologies such as employment of co-culture, genetic and metabolic engineering, immobilization technique and efficient bioreactor systems.

  2. Recent advances in amino acid analysis by capillary electrophoresis.

    PubMed

    Poinsot, Véréna; Carpéné, Marie-Anne; Bouajila, Jalloul; Gavard, Pierre; Feurer, Bernard; Couderc, François

    2012-01-01

    This paper describes the most important articles that have been published on amino acid analysis using CE during the period from June 2009 to May 2011 and follows the format of the previous articles of Smith (Electrophoresis 1999, 20, 3078-3083), Prata et al. (Electrophoresis 2001, 22, 4129-4138) and Poinsot et al. (Electrophoresis 2003, 24, 4047-4062; Electrophoresis 2006, 27, 176-194; Electrophoresis 2008, 29, 207-223; Electrophoresis 2010, 31, 105-121). We present new developments in amino acid analysis with CE, which are reported describing the use of lasers or light emitting diodes for fluorescence detection, conductimetry electrochemiluminescence detectors, mass spectrometry applications, and lab-on-a-chip applications using CE. In addition, we describe articles concerning clinical studies and neurochemical applications of these techniques.

  3. Micro-structural design and function of an improved absorptive glass mat (AGM) separator for valve-regulated lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Nakayama, Y.; Kishimoto, K.; Sugiyama, S.; Sakaguchi, S.

    Two important properties of absorptive glass mat (AGM) separators are examined in order to design optimum separators for advanced valve-regulated lead-acid (VRLA) batteries. Acid stratification in the separator depends on its micro-glass-fibre diameter, and it is found that the extent of stratification can be estimated based on hydrodynamics theory. Decreasing the plate-group pressure of the separator in the wetted state is also investigated, and it is considered that the phenomenon is caused by the balance between the fibre strength and the surface tension of acid solution. Given these results, the way to design AGM separators according to purpose has been identified. Accordingly, a new AGM separator has been developed and this functions both to suppress stratification and to maintain plate-group pressure.

  4. Recent Advances in Fatty Acid Perception and Genetics123

    PubMed Central

    Reed, Danielle R; Xia, Mary B

    2015-01-01

    This article summarizes new knowledge about the contribution of genetic variation to person-to-person differences underlying some sensory aspects of dietary fatty acids. Receptors on the taste cells of the human tongue arise from genes that have marked variation in DNA sequence, which, in some cases, is associated with differences in how these lipids in foods are perceived. These perceptual differences may affect food selection. PMID:25979508

  5. Health hazards of China's lead-acid battery industry: a review of its market drivers, production processes, and health impacts.

    PubMed

    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

  6. Advances in Lead-Free Piezoelectric Materials for Sensors and Actuators

    PubMed Central

    Aksel, Elena; Jones, Jacob L.

    2010-01-01

    Piezoelectrics have widespread use in today’s sensor and actuator technologies. However, most commercially available piezoelectric materials, e.g., Pb [ZrxTi1−x] O3 (PZT), are comprised of more than 60 weight percent lead (Pb). Due to its harmful effects, there is a strong impetus to identify new lead-free replacement materials with comparable properties to those of PZT. This review highlights recent developments in several lead-free piezoelectric materials including BaTiO3, Na0.5Bi0.5TiO3, K0.5Bi0.5TiO3, Na0.5K0.5NbO3, and their solid solutions. The factors that contribute to strong piezoelectric behavior are described and a summary of the properties for the various systems is provided. PMID:22294907

  7. Lead halide perovskites: Challenges and opportunities in advanced synthesis and spectroscopy

    DOE PAGES

    Rosales, Bryan A.; Hanrahan, Michael P.; Boote, Brett W.; ...

    2017-03-03

    Hybrid lead perovskites containing a mixture of organic and inorganic cations and anions have lead to solar cell devices with better performance and stability than their single halide analogs. Here, 207Pb solid-state nuclear magnetic resonance and single particle photoluminescence spectroscopies show that the structure and composition of mixed-halide and—likely—other hybrid lead perovskites is much more complex than previously thought and is highly dependent on their synthesis. While a majority of reports in the area focus on the construction of photovoltaic devices, this perspective focuses instead on achieving a better understanding of the fundamental chemistry and photophysics of these materials, asmore » this will aid not only in constructing improved devices, but also in generating new uses for these unique materials.« less

  8. Charging Algorithm Extends the Life of Lead-acid Batteries: 2001 R and D 100 Award Recipient

    SciTech Connect

    Pesaran, A.

    2001-09-27

    Fact sheet describing NREL's work with Recombination Technologies and Optima Batteries to develop a current interrupt charging algorithm to extend the deep life cycle of valve-regulated lead-acid batteries.

  9. Leading the Campaign: Advancing Colleges and Universities. The ACE Series on Higher Education

    ERIC Educational Resources Information Center

    Worth, Michael J.

    2010-01-01

    The ability to lead a campaign is essential to success for today's college or university president. And campaign experience at some level is generally now a prerequisite credential for presidential candidates, as well as deans and other academic leaders, on both public and private campuses. This book discusses fundamental campaign principles, but…

  10. Advances in the hydrogeochemistry and microbiology of acid mine waters

    USGS Publications Warehouse

    Nordstrom, D. Kirk

    2000-01-01

    The last decade has witnessed a plethora of research related to the hydrogeochemistry and microbiology of acid mine waters and associated tailings and waste-rock waters. Numerous books, reviews, technical papers, and proceedings have been published that examine the complex bio-geochemical process of sulfide mineral oxidation, develop and apply geochemical models to site characterization, and characterize the microbial ecology of these environments. This review summarizes many of these recent works, and provides references for those investigating this field. Comparisons of measured versus calculated Eh and measured versus calculated pH for water samples from several field sites demonstrate the reliability of some current geochemical models for aqueous speciation and mass balances. Geochemical models are not, however, used to predict accurately time-dependent processes but to improve our understanding of these systems and to constrain possible processes that contribute to actual or potential water quality issues. Microbiological studies are demonstrating that there is much we have yet to learn about the types of different microorganisms and their function and ecology in mine-waste environments. A broad diversity of green algae, bacteria, archaea, yeasts, and fungi are encountered in acid mine waters, and a better understanding of their ecology and function may potentially enhance remediation possibilities as well as our understanding of the evolution of life.

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

    NASA Astrophysics Data System (ADS)

    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.

  12. New accelerated charge methods using early destratification applied on flooded lead acid batteries

    NASA Astrophysics Data System (ADS)

    Mamadou, K.; Nguyen, T. M. P.; Lemaire-Potteau, E.; Glaize, C.; Alzieu, J.

    A traditional charge process for flooded lead acid batteries (FLABs) lasts generally from 8 to 14 h. Nowadays, many applications of FLABs require reduction of the charge duration, for instance, a 4 h-charge for FLABs in grid energy storage or 1 h-charge for FLABs in electric buses. These are called accelerated charge and fast charge. Such reductions of charge time imply the use of a new charge process. One way to reduce the charge duration is to perform an early destratification step without waiting for the end of charge. The new charge method proposed in this paper (early destratification method - ED) focuses on the reduction of the charge time for FLABs using early destratification, which is performed and controlled using charge acceptance measurement during the charge. Laboratory experiments presented here aim first to develop charge acceptance measurements followed by an ED charge method compared to an IUi traditional charge process.

  13. 180 Ah kg-1 specific capacity positive tubular electrodes for lead acid batteries

    NASA Astrophysics Data System (ADS)

    de Andrade, J.; Impinnisi, P. R.; do Vale, D. L.

    2011-05-01

    Two disadvantages of lead acid batteries are poor power and energy densities and the necessity of relatively long recharging times. In this paper it is presented the results of ongoing work aimed at increasing both the positive active material (PAM) specific capacity and the positive plate charge acceptability. The experimental results show that adequate curing processes can be used to develop an interconnected structure among nanometric PbO2 particles to produce tubular electrodes with specific capacity higher than 180 Ah kg-1 and maintain this value for 130 cycles with deep discharges. These PbO2 positive plates are expected to exhibit higher charge acceptability due to their larger PAM surface area as compared to conventional ones, but the results indicate that the high internal ohmic resistance of the grid/PAM zone limits the fast charge efficiency.

  14. Electrolyte depletion control laws for lead-acid battery discharge optimisation

    NASA Astrophysics Data System (ADS)

    Tenno, R.; Nefedov, E.

    2014-12-01

    The technique described in this paper balances the power and energy withdrawn from a battery in galvanostatic discharge control that aims for stabilisation of the electrolyte concentration above the depletion level. This aim is achieved with relatively simple proportional feedback controls that are exponentially stabilising controls for a simple diffusion process that is the core part of battery processes. Although the full mapping of the proposed controls to state is rather complex, it has shown that the transformation works. In practice, these controls can be approximated either with the integrated past controls or with a simple exponential function that depends on a few parameters adjusted to the electrochemical processes in a battery under consideration. The battery control is tested in simulation on a detailed model developed for a lead-acid electrochemical cell.

  15. A fractional order model for lead-acid battery crankability estimation

    NASA Astrophysics Data System (ADS)

    Sabatier, J.; Cugnet, M.; Laruelle, S.; Grugeon, S.; Sahut, B.; Oustaloup, A.; Tarascon, J. M.

    2010-05-01

    With EV and HEV developments, battery monitoring systems have to meet the new requirements of car industry. This paper deals with one of them, the battery ability to start a vehicle, also called battery crankability. A fractional order model obtained by system identification is used to estimate the crankability of lead-acid batteries. Fractional order modelling permits an accurate simulation of the battery electrical behaviour with a low number of parameters. It is demonstrated that battery available power is correlated to the battery crankability and its resistance. Moreover, the high-frequency gain of the fractional model can be used to evaluate the battery resistance. Then, a battery crankability estimator using the battery resistance is proposed. Finally, this technique is validated with various battery experimental data measured on test rigs and vehicles.

  16. Online impedance spectroscopy of lead acid batteries for storage management of a standalone power plant

    NASA Astrophysics Data System (ADS)

    Depernet, Daniel; Ba, Oumar; Berthon, Alain

    2012-12-01

    This paper presents a contribution to implementation of hybrid power plants in rural areas without electricity in Senegal. Wind and photovoltaic generators coupling is used to benefit from renewable energy resources in this country. Lead acid storage batteries are coupled with the generators to ensure smoothness of the electricity generation. This work is focused in particular on the development of a low cost online impedance spectroscopy method to address the problem of limited lifetime of batteries and the difficulties of their maintenance in isolated areas. Control of static converter associated with the battery is adapted to integrate the functionality of characterization of batteries by impedance spectroscopy. An experimental platform developed in the laboratory has validated the method for online measurement of battery impedance spectrum and to initiate a phase of data monitoring.

  17. Wind-tunnel studies of advanced cargo aircraft concepts. [leading edge vortex flaps for drag reduction

    NASA Technical Reports Server (NTRS)

    Rao, D. M.; Goglia, G. L.

    1981-01-01

    Accomplishments in vortex flap research are summarized. A singular feature of the vortex flap is that, throughout the range of angle of attack range, the flow type remains qualitatively unchanged. Accordingly, no large or sudden change in the aerodynamic characteristics, as happens when forcibly maintained attached flow suddenly reverts to separation, will occur with the vortex flap. Typical wind tunnel test data are presented which show the drag reduction potential of the vortex flap concept applied to a supersonic cruise airplane configuration. The new technology offers a means of aerodynamically augmenting roll-control effectiveness on slender wings at higher angles of attack by manipulating the vortex flow generated from leading edge separation. The proposed manipulator takes the form of a flap hinged at or close to the leading edge, normally retracted flush with the wing upper surface to conform to the airfoil shape.

  18. The key to success: Gelled-electrolyte and optimized separators for stationary lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Toniazzo, Valérie

    The lead acid technology is nowadays considered one of the best suited for stationary applications. Both gel and AGM batteries are complementary technologies and can provide reliability and efficiency due to the constant optimization of the battery design and components. However, gelled-electrolyte batteries remain the preferred technology due to a better manufacturing background and show better performance mainly at low and moderate discharge rates. Especially, using the gel technology allows to get rid of the numerous problems encountered in most AGM batteries: drainage, stratification, short circuits due to dendrites, and mostly premature capacity loss due to the release of internal cell compression. These limitations are the result of the evident lack of an optimal separation system. In gel batteries, on the contrary, highly efficient polymeric separators are nowadays available. Especially, microporous separators based on PVC and silica have shown the best efficiency for nearly 30 years all over the world, and especially in Europe, where the gel technology was born. The improved performance of these separators is explained by the unique extrusion process, which leads to excellent wettability, and optimized physical properties. Because they are the key for the battery success, continuous research and development on separators have led to improved properties, which render the separator even better adapted to the more recent gel technology: the pore size distribution has been optimized to allow good oxygen transfer while avoiding dendrite growth, the pore volume has been increased, the electrical resistance and acid displacement reduced to such an extent that the electrical output of batteries has been raised both in terms of higher capacity and longer cycle life.

  19. Effect of acid rain pH on leaching behavior of cement stabilized lead-contaminated soil.

    PubMed

    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.

  20. [Study advance on haloacetic acids in drinking water].

    PubMed

    Ye, Bi-Xiong; Wang, Wu-Yi; Yang, Lin-Sheng; Wang, Yong-Hua

    2006-05-01

    Haloacetic acids (HAAs) in drinking water have attracted more and more attention of researchers due to their higher potential combination of chlorine, their carcinogenic and mutagenic effects and higher carcinogenic. The formation mechanism, analytical methods, the effects of many factors on HAAs formation such as precursor types, chlorine doses, pH, temperature, bromide, reaction time and seasonal change, toxicological character and the minimizing technology of HAAs in resent studies about HAAs are discussed in details in this paper. Further researches are still needed to clarify the formation mechanism of HAAs and find a feasible minimizing technology. New concerns including toxicological characters that correlate with human and other HAAs exposure routes besides oral ingestion (i.e., inhalation and dermal adsorption) should be put forward.

  1. Quartz resonator state-of-charge monitor for lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Cernosek, R. W.; Martin, S. J.; Wessendorf, K. O.; Rumpf, A. N.

    We have demonstrated that a thickness shear mode quartz resonator can be used as a real-time, in situ monitor of the state-of-charge of lead-acid batteries. The resonator is sensitive to changes in the density and viscosity of the sulfuric acid electrolyte. Both of these liquid parameters vary monotonically with the battery state-of-charge. This new monitor is more precise than sampling hydrometers, and since it is compatible with the corrosive electrolyte environment, it can be used for in situ monitoring. A TSM resonator consists of gold electrodes deposited on opposite surfaces of a thin AT-cut quartz crystal. When an RF voltage is applied to the electrodes, a shear strain is introduced in the piezoelectric quartz and mechanical resonance occurs between the surfaces. A liquid in contact with one of the quartz surfaces is viscously entrained, which perturbs the resonant frequency and resonance magnitude. If the surface is smooth, the changes in both frequency and magnitude are proportional to (rho(eta))(exp (1/2)), where rho is the liquid density and eta is the viscosity.

  2. Quartz resonator state-of-charge monitor for lead-acid batteries

    SciTech Connect

    Cernosek, R.W.; Martin, S.J.; Wessendorf, K.O.; Rumpf, A.N.

    1994-06-01

    We have demonstrated that a thickness shear mode quartz resonator can be used as a real-time, in situ monitor of the state-of-charge of lead-acid batteries. The resonator is sensitive to hanges in the density and viscosity of the sulfuric acid electrolyte. Both of these liquid parameters vary monotonically with the battery state-of-charge. This new monitor is more precise than sampling hydrometers, and since it is compatible with the Corrosive electrolyte environment, it can be used for in situ monitoring. A TSM resonator consists of gold electrodes deposited on opposite surfaces of a thin AT-cut quartz crystal. When an RF voltage is applied to the electrodes, a shear strain is introduced in the piezoelectric quartz and mechanical resonance occurs between the surfaces. A liquid in contact with one of the quartz surfaces is viscously entrained, which perturbs the resonant frequency and resonance magnitude. If the surface is smooth, the changes in both frequency and magnitude are proportional to ({rho}{eta}) {sup {1/2}}, where {rho} is the liquid density and {eta} is the viscosity.

  3. Characterisation of separator papers for use in valve regulated lead/acid batteries

    NASA Astrophysics Data System (ADS)

    Ball, R. J.; Evans, R.; Stevens, R.

    Separator papers are an essential component of a valve regulated lead/acid (VRLA) battery. In addition to separating the positive and negative electrodes, they provide a constant pressure on the active materials thereby reducing the rate of degradation during cycling. Dendrites formed from the negative active material are also less likely to cause short circuits in batteries where a separator is employed. The level to which a separator will influence the performance of a VRLA battery it strongly dependent on its properties. This paper describes the results from a series of tests used to characterise the properties of separators most influential to battery performance. These properties include, the macroscopic structure, permittivity and wicking rates. During the operational life of a VRLA battery the volume of electrolyte will decrease, due mainly to the electrolysis of water during overcharging. The consequence of this process is a variation of acid saturation during the life of the battery, which will have a direct influence on the compressive and diffusive properties of the separator. Compressive and diffusive characteristics were therefore measured over a range of saturation levels. Characterisation was conducted on three separator types. Types A and B were 100% glass but had slightly different structures and type C contained 8% polyester fibres mixed with glass.

  4. Lead binding to soil fulvic and humic acids: NICA-Donnan modeling and XAFS spectroscopy.

    PubMed

    Xiong, Juan; Koopal, Luuk K; Tan, WenFeng; Fang, LinChuan; Wang, MingXia; Zhao, Wei; Liu, Fan; Zhang, Jing; Weng, LiPing

    2013-10-15

    Binding of lead (Pb) to soil fulvic acid (JGFA), soil humic acids (JGHA, JLHA), and lignite-based humic acid (PAHA) was investigated through binding isotherms and XAFS. Pb binding to humic substances (HS) increased with increasing pH and decreasing ionic strength. The NICA-Donnan model described Pb binding to the HS satisfactorily. The comparison of the model parameters showed substantial differences in median Pb affinity constants among JGFA, PAHA, and the soil HAs. Milne's "generic" parameters did not provide an adequate prediction for the soil samples. The Pb binding prediction with generic parameters for the soil HAs was improved significantly by using the value n(Pb1) = 0.92 instead of the generic value n(Pb1) = 0.60. The n(Pb1)/n(H1) ratios obtained were relatively high, indicating monodentate Pb binding to the carboxylic-type groups. The nPb2/nH2 ratios depended somewhat on the method of optimization, but the values were distinctly lower than the n(Pb1)/nH1 ratios, especially when the optimization was based on Pb bound vs log [Pb(2+)]. These low values indicate bidentate binding to the phenolic-type groups at high Pb concentration. The NICA-Donnan model does not consider bidentate binding of Pb to a carboxylic- and a phenolic-type group. The EXAFS results at high Pb loading testified that Pb was bound in bidentate complexes of one carboxylic and one phenolic group (salicylate-type) or two phenolic groups (catechol-type) in ortho position.

  5. Oxadiazoles as privileged motifs for promising anticancer leads: recent advances and future prospects.

    PubMed

    Khan, Imtiaz; Ibrar, Aliya; Abbas, Naeem

    2014-01-01

    Taking into account the rising trend of the incidence of cancers of various organs, effective therapies are urgently needed to control human malignancies. The rapid emergence of hundreds of new agents that modulate an ever-growing list of cancer-specific molecular targets offers tremendous hope for cancer patients. However, almost all of the chemotherapy drugs currently on the market cause serious side effects. Based on these facts, the design of new chemical entities as anticancer agents requires the simulation of a suitable bioactive pharmacophore. The pharmacophore not only should have the required potency but must also be safer on normal cell lines than on tumor cells. In this perspective, oxadiazole scaffolds with well-defined anticancer activity profile have fueled intense academic and industrial research in recent years. This paper is intended to highlight the recent advances along with current developments as well as future outlooks for the design of novel and efficacious anticancer agents based on oxadiazole motifs.

  6. A novel leady oxide combined with porous carbon skeleton synthesized from lead citrate precursor recovered from spent lead-acid battery paste

    NASA Astrophysics Data System (ADS)

    Hu, Yuchen; Yang, Jiakuan; Zhang, Wei; Xie, Yanlin; Wang, Junxiong; Yuan, Xiqing; Vasant Kumar, R.; Liang, Sha; Hu, Jingping; Wu, Xu

    2016-02-01

    A novel nanostructured leady oxides comprising porous carbon skeleton has been synthesized by thermal decomposition of lead citrate precursor, recovered from spent lead-acid battery paste. The influences of O2 percentage in the calcination atmosphere (O2/N2 mixture) and the temperature on leady oxide product characteristics are studied by chemical analysis, scanning electron microscopy (SEM) and X-ray diffraction (XRD). The major crystalline phases of the products are identified as lead oxides, metallic Pb, and carbon. Porous carbon is observed as skeletons within the leady oxide (PbO containing some Pb metal) particles. Mass percentage of Pb metal in the leady oxide increases with increasing the proportion of oxygen in the calcination atmosphere. However, the amount of carbon decreases from approximately 8.0 to 0.3 wt%, and the porous carbon skeleton structure is gradually damaged with oxygen concentration increasing. A model about the thermal decomposition of lead citrate precursor is firstly proposed to elucidate these observations. The nanostructured leady oxides combined with porous carbon can be directly used as precursor of active materials in a new lead acid battery.

  7. Influence of H 2SO 4 concentration on the performance of lead-acid battery negative plates

    NASA Astrophysics Data System (ADS)

    Pavlov, D.; Petkova, G.; Rogachev, T.

    The influence of sulfuric acid concentration on negative plate performance has been studied on 12 V/32 Ah lead-acid batteries with three negative and four positive plates per cell, i.e. the negative active material limits battery capacity. Initial capacity tests, including C20 capacity, cold cranking ability and Peukert tests, have been carried out in a wide range of sulfuric acid concentrations (from 1.18 to 1.33 sp.gr.). High initial capacity and good CCA performance were registered for batteries with acid concentration between 1.24 and 1.30 sp.gr. The charge acceptance depends on acid concentration as well as on battery state of charge. Batteries with high SoC exhibit high charge acceptance at low acid concentrations. The cycle life tests at two discharge rates (10 and 3 h discharge) evidence that sulfuric acid concentration exerts a strong effect on negative plate performance. The cycle life of batteries decreases with increase of acid concentration. The obtained results demonstrate the high impact of lead sulfate solubility on the cycle life and charge efficiency of lead-acid batteries.

  8. Woven-grid sealed quasi-bipolar lead-acid battery construction and fabricating method

    NASA Technical Reports Server (NTRS)

    Rippel, Wally E. (Inventor)

    1989-01-01

    A quasi-bipolar lead-acid battery construction includes a plurality of bipolar cells disposed in side-by-side relation to form a stack, and a pair of monoplanar plates at opposite ends of the stack, the cell stack and monopolar plates being contained within a housing of the battery. Each bipolar cell is loaded with an electrolyte and composed of a bipolar electrode plate and a pair of separator plates disposed on opposite sides of the electrode plate and peripherally sealed thereto. Each bipolar electrode plate is composed of a partition sheet and two bipolar electrode elements folded into a hairpin configuration and applied over opposite edges of the partition sheet so as to cover the opposite surfaces of the opposite halves thereof. Each bipolar electrode element is comprised of a woven grid with a hot-melt strip applied to a central longitudinal region of the grid along which the grid is folded into the hairpin configuration, and layers of negative and positive active material pastes applied to opposite halves of the grid on opposite sides of the central hot-melt strip. The grid is made up of strands of conductive and non-conductive yarns composing the respective transverse and longitudinal weaves of the grid. The conductive yarn has a multi-stranded glass core surrounded and covered by a lead sheath, whereas the non-conductive yarn has a multi-stranded glass core surrounded and covered by a thermally activated sizing.

  9. Novel polymer-graphite composite grid as a negative current collector for lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Zhang, Shukai; Zhang, Hao; Cheng, Jie; Zhang, Wenfeng; Cao, Gaoping; Zhao, Hailei; Yang, Yusheng

    2016-12-01

    We design a novel polymer-graphite composite grid as the negative current collector for lead-acid batteries. With this novel grid, the negative active material (NAM) can deliver a specific capacity of 170 mAh g-1 at a discharge rate of 0.1 C. After that, we conduct structural optimization and surface treatment on the grid to improve its performance. Through the structural optimization, additional lead pastes can be loaded and the cycle stability of the battery is enhanced. By using the optimized grid, the weight of the negative current collector can be remarkably reduced by more than 50%. To handle the serious hydrogen evolution on the graphite surface and the unfavorable adhesion between graphite and NAM, fine PbSO4 particles are coated onto the surface of the graphite grids by chemical deposition. The cells employing the PbSO4-deposition grids exhibit excellent cycling stability as well as low polarization and then high Coulombic efficiency. We present here a possible mechanism that how PbSO4 deposits effectively enhance the performance of negative plates based on the testing results.

  10. Investigations of the negative plate of lead/acid cells 1. Selection of additives

    NASA Astrophysics Data System (ADS)

    Saakes, Michel; J. Van Duin, Pieter; C. P. Ligtvoet, Alexander; Schmal, Dick

    A procedure is proposed for the selection of inhibitors and expanders used as additives for the negative plate of the lead/acid battery. Inhibitors were selected by performing d.c. and a.c. measurements at pure metals (Cu, Sb, Ag), which are assumed to act as local active sites for the hydrogen-evolution reaction at the negative plate. From this study anisaldehyde was found to show strong preferential adsorption at Cu and Sb. Expanders were selected using a.c. impedance measurements at a Pb electrode at a low anodic discharge current. Selected expanders were Indulin C and Na-1-naphtol-4-sulfonate. From the impedance measurements information was obtained not only on the expander action but also on the effect of the additive on the double layer and the diffusion properties of lead sulfate. From a study on the concentration dependence of the expander (Na-1-naphtol-4-sulfonate) an optimal effect was found at a concentration of about 600 ppm.

  11. Research, development, and demonstration of lead-acid batteries for electric-vehicle propulsion. Annual report for 1982

    SciTech Connect

    Bowman, D.E.

    1983-08-01

    Research programs on lead-acid batteries are reported that cover active materials utilization, active material integrity, and some technical support projects. Processing problems were encountered and corrected. Components and materials, a lead-plastic composite grid, cell designs, and deliverables are described. Cell testing is discussed, as well as battery subsystems, including fuel gage, thermal management, and electrolyte circulation. (LEW)

  12. The Effect of Ascorbic Acid and Garlic Administration on Lead-Induced Neural Damage in Rat Offspring’s Hippocampus

    PubMed Central

    Sadeghi, Akram; Ebrahimzadeh Bideskan, Alireza; Alipour, Fatemeh; Fazel, Alireza; Haghir, Hossein

    2013-01-01

    Objective(s): The aim of this study was to investigate ascorbic acid and garlic protective effects on lead-induced neurotoxicity during rat hippocampus development. Materials and Methods: 90 pregnant wistar rats were divided randomly into nine groups: 1- Animals received leaded water (L). 2- Rats received leaded water and ascorbic acid (L+AA). 3- Animals received leaded water and garlic juice (L+G). 4-Animals received leaded water, ascorbic acid and garlic juice (L+G+AA). 5- Rats treated with ascorbic acid (AA). 6- Rats treated with garlic juice (G). 7- Rats treated with ascorbic acid and garlic juice (AA+G). 8- Rats treated with tap water plus 0.4 ml/l normal hydrogen chloride (HCl) and 0.5 mg/l Glucose (Sham). 9- Normal group (N). Leaded water (1500 ppm), garlic juice (1 ml/100g/day, gavage) and ascorbic acid (500 mg/kg/day, IP) were used. Finally, blood lead levels (BLL) were measured in both rats and their offspring. The rat offspring brain sections were stained using Toluidine Blue and photographed. Dark neurons (DNs) were counted to compare all groups. Results: BLL significantly increased in L group compared to control and sham groups and decreased in L+G and L+AA groups in comparison to the L group (P<0.05). the number of DNs in the CA1, CA3, and DG of rat offspring hippocampus significantly increased in L group in comparison to control and sham groups (P<0.05) and decreased in L+G and L+AA groups compared to L group (P<0.05). Conclusion: Garlic juice and ascorbic acid administration during pregnancy and lactation may protect lead-induced neural damage in rat offspring hippocampus. PMID:24298384

  13. Protective effect of boric acid on lead- and cadmium-induced genotoxicity in V79 cells.

    PubMed

    Ustündağ, Aylin; Behm, Claudia; Föllmann, Wolfram; Duydu, Yalçin; Degen, Gisela H

    2014-06-01

    The toxic heavy metals cadmium (Cd) and lead (Pb) are important environmental pollutants which can cause serious damage to human health. As the metal ions (Cd(2+) and Pb(2+)) accumulate in the organism, there is special concern regarding chronic toxicity and damage to the genetic material. Metal-induced genotoxicity has been attributed to indirect mechanisms, such as induction of oxidative stress and interference with DNA repair. Boron is a naturally occurring element and considered to be an essential micronutrient, although the cellular activities of boron compounds remain largely unexplored. The present study has been conducted to evaluate potential protective effects of boric acid (BA) against genotoxicity induced by cadmium chloride (CdCl2) and lead chloride (PbCl2) in V79 cell cultures. Cytotoxicity assays (neutral red uptake and cell titer blue assay) served to determine suitable concentrations for subsequent genotoxicity assays. Chromosomal damage and DNA strand breaks were assessed by micronucleus tests and comet assays. Both PbCl2 and CdCl2 (at 3, 5 and 10 µM) were shown to induce concentration-dependent increases in micronucleus frequencies and DNA strand breaks in V79 cells. BA itself was not cytotoxic (up to 300 µM) and showed no genotoxic effects. Pretreatment of cells with low levels of BA (2.5 and 10 µM) was found to strongly reduce the genotoxic effects of the tested metals. Based on the findings of this in vitro study, it can be suggested that boron provides an efficient protection against the induction of DNA strand breaks and micronuclei by lead and cadmium. Further studies on the underlying mechanisms for the protective effect of boron are needed.

  14. Influence of bismuth on the charging ability of negative plates in lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Lam, L. T.; Ceylan, H.; Haigh, N. P.; Manders, J. E.

    To examine the influence of bismuth on the charging ability of negative plates in lead-acid batteries, plates are made from three types of oxides: (i) leady oxide of high quality which contains virtually no bismuth (termed 'control oxide'); (ii) control oxide in which bismuth oxide is blended at bismuth levels from 0.01 to 0.12 wt.%; (iii) leady oxide produced from Pasminco VRLA Refined™ lead (0.05-0.06 wt.%Bi). An experimental tool—the 'conversion indicator'—is developed to assess the charging ability of the test negative plates when cycling under either zero percent state-of-charge (SoC)/full-charge or partial state-of-charge (PSoC) duty. Although the conversion indicator is not the true charging efficiency, the two parameters have a close relationship, namely, the higher the conversion indicator, the greater the charging efficiency. Little difference is found in the charging ability, irrespective of bismuth content and discharge rate, when the plates are subjected to zero percent SoC/full-charge duty; the conversion indicator lies in the range 81-84%. By contrast, there is a marked difference when the negative plates are subjected to PSoC duty, i.e. consecutive cycling through 90-60, 70-40, 80-40 and 90-40% SoC windows. Up to 0.06 wt.%Bi improves the charging ability, especially with a low and narrow PSoC window (40-70% SoC) of the type that will be experienced in 42 V powernet automobile and hybrid electric duties. To maximize this beneficial effect, bismuth must be distributed uniformly in the plates. This is best achieved by using VRLA Refined™ lead for oxide production.

  15. Removal of sulfuric acid mist from lead-acid battery plants by coal fly ash-based sorbents.

    PubMed

    Shu, Yuehong; Wei, Xiangyu; Fang, Yu; Lan, Bingyan; Chen, Hongyu

    2015-04-09

    Sorbents from coal fly ash (CFA) activated by NaOH, CaO and H2O were prepared for H2SO4 mist removal from lead-acid battery plants. The effects of parameters including temperature, time, the ratios of CFA/activator and water/solid during sorbent preparation were investigated. It is found that the synthesized sorbents exhibit much higher removal capacity for H2SO4 mist when compared with that of raw coal fly ash and CaO except for H2O activated sorbent and this sorbent was hence excluded from the study because of its low capacity. The H2SO4 mist removal efficiency increases with the increasing of preparation time length and temperature. In addition, the ratios of CFA/activator and water/solid also impact the removal efficiency, and the optimum preparation conditions are identified as: a water/solid ratio of 10:1 at 120 °C for 10h, a CFA:CaO weight ratio of 10:1, and a NaOH solution concentration of 3 mol/L. The formation of rough surface structure and an increased surface area after NaOH/CaO activation favor the sorption of H2SO4 mist and possible sorption mechanisms might be electrostatic attractions and chemical precipitation between the surface of sorbents and H2SO4 mist.

  16. Development of advanced kocite electrocatalysts for phosphoric acid fuel cells

    NASA Astrophysics Data System (ADS)

    Welsh, L. S.; Leyerle, R. W.; Scarlata, D. S.; Vanek, M. A.

    1981-01-01

    These improved electrocatalysts should demonstrate a larger initial catalytic metal surface area, and a better catalytic metal surface area retention during fuel cell operation than present state-of-the-art phosphoric acid electrocatalysts. Kocite electrocatalysts impregnated with platinum and platinum-vanadium alloys were tested. The Kocite electrocatalysts were aged in electrodes potentiostated in H3PO4 half cells, and were then analyzed for catalytic metals surface area retention. Compared with the state-of-the-art platinum electrocatalysts, as represented by a standard Kocite electrocatalyst, the Kocite electrocatalysts impregnated by the techniques used in this study have a better initial platinum surface area. This initial surface area difference appeared to be maintained when the catalysts are aged at 700 mV, but was not maintained when the catalysts were aged at 800 mV. Variations of the alumina substrate and of the post-treatment of the leached Kocite catalyst support did not produce any catalysts with better platinum surface area retention than the standard catalyst. Alloying of vanadium with the platinum did produce Kocite electrocatalysts which maintained their alloy surface area better than the standard catalyst maintained its platinum surface area.

  17. How the UK Can Lead the Terrestrial Translation of Biomedical Advances Arising from Lunar Exploration Activities

    NASA Astrophysics Data System (ADS)

    Green, David A.

    2010-12-01

    Terrestrial translation of biomedical advances is insufficient justification for lunar exploration. However, terrestrial translation should be viewed as a critical part of the cycle of mission planning, execution and review, both in terms of the progress of space exploration, but also of sustained life on Earth. Thus, both the mission and its potential to benefit mankind are increased by the adoption of human-based exploration of the lunar surface. Whilst European biomedical sciences have grown in stature, there remains a gap between space biomedical science and terrestrial medical application. As such, an opportunity for the UK to take a sustainable leadership role exists by utilising its biomedical science community, socialised health care system (National Health Service) and defined mechanisms to determine the clinical efficacy and cost-effectiveness upon health and wellbeing (i.e. National Institute Clinical Excellence), aiding the difficult process of health care rationing. By focusing upon exploitation of the more scientifically rewarding, potentially long-term and more terrestrially analogous challenge of lunar habitation, the UK would circumnavigate the current impediments to International Space Station utilisation. Early engagement in lunar exploration would promote the UK, and its adoption of a leadership role incorporating a considered approach to the development of space biomedicine with an eye to its terrestrial value. For instance, prolonged lunar habitation could provide an `ideal controlled environment' for investigation of medical interventions, in particular multiple interactions (e.g. between exercise and nutrition), a model of accelerated aging and a number of chronic pathologies, including those related to disuse. Lunar advances could provide a springboard for individualized medicine, insights into occupational and de-centralised medicine (e.g. telemedicine) and act as a stimulus for biomedical innovation and understanding. Leadership in

  18. NREL Advancements in Methane Conversion Lead to Cleaner Air, Useful Products

    SciTech Connect

    2016-06-01

    Researchers at NREL leveraged the recent on-site development of gas fermentation capabilities and novel genetic tools to directly convert methane to lactic acid using an engineered methanotrophic bacterium. The results provide proof-of-concept data for a gas-to-liquids bioprocess that concurrently produces fuels and chemicals from methane. NREL researchers developed genetic tools to express heterologous genes in methanotrophic organisms, which have historically been difficult to genetically engineer. Using these tools, researchers demonstrated microbial conversion of methane to lactate, a high-volume biochemical precursor predominantly utilized for the production of bioplastics. Methane biocatalysis offers a means to concurrently liquefy and upgrade natural gas and renewable biogas, enabling their utilization in conventional transportation and industrial manufacturing infrastructure. Producing chemicals and fuels from methane expands the suite of products currently generated from biorefineries, municipalities, and agricultural operations, with the potential to increase revenue and significantly reduce greenhouse gas emissions.

  19. Application of the quartz crystal microbalance to measurement of the concentration of electrolyte in lead-acid batteries

    SciTech Connect

    Charlesworth, J.M.; Garrard, W.N.C.

    1995-12-01

    The density of the electrolyte in a lead-acid battery may change by 10-20% during the discharge-charge cycle and the value within this range can be used as an indication of the fraction of available energy stored in the battery. We describe the application of a quartz crystal microbalance to the determination of the density of sulphuric acid solutions over a range of temperatures and during the discharge of a typical lead-acid battery. The sensor response varied linearly with temperature and in a quadratic manner with the density of the solution. Good agreement with the theoretically predicted behavior of thickness shear mode oscillators immersed in liquids was observed. The sensor performed well in the laboratory experiments using artificial conditions; however, initial studies using the sensor in a lead-acid battery operating under real conditions revealed that stray capacitances could influence the oscillator stability.

  20. Building strong relationships between conservation genetics and primary industry leads to mutually beneficial genomic advances.

    PubMed

    Galla, Stephanie J; Buckley, Thomas R; Elshire, Rob; Hale, Marie L; Knapp, Michael; McCallum, John; Moraga, Roger; Santure, Anna W; Wilcox, Phillip; Steeves, Tammy E

    2016-11-01

    Several reviews in the past decade have heralded the benefits of embracing high-throughput sequencing technologies to inform conservation policy and the management of threatened species, but few have offered practical advice on how to expedite the transition from conservation genetics to conservation genomics. Here, we argue that an effective and efficient way to navigate this transition is to capitalize on emerging synergies between conservation genetics and primary industry (e.g., agriculture, fisheries, forestry and horticulture). Here, we demonstrate how building strong relationships between conservation geneticists and primary industry scientists is leading to mutually-beneficial outcomes for both disciplines. Based on our collective experience as collaborative New Zealand-based scientists, we also provide insight for forging these cross-sector relationships.

  1. Research on the fiber reflecting sensor for detecting the residual capacity of the lead-acid battery

    NASA Astrophysics Data System (ADS)

    Zhao, Mingfu; Zhong, Nianbing; Chen, Yan; Luo, Yuwei

    2006-11-01

    According to the Lambert-Bee law, we can see that the photic absorption coefficient is related to the matter's concentration, the distance of the light through the absorption medium and the transmitted light intensity. The paper just according to the physical phenomena and the theory make the reflex energy relate to the concentration testing of the electrolyte, at the same time the electrolyte's concentration is related to the capacity of lead-acid battery on a corresponding function relation, so we can know the capacity state of the lead-acid battery according to the measurement on the electrolyte's concentration. According to the experiment and research the author deeply discussed how the temperature change affects the capacity of lead-acid battery and the concentration's changing relation, according to the analyses of the thermo-optic effect, we made a new reflecting fiber sensor based on the comparative temperature testing theory and absorption which can eliminate the temperature effect on the tested signal namely the output signal just related to the concentration, so really reflects the change of the capacity of the lead-acid battery when it is in the charge and discharge process. The results of the experiment and theory analyses show that this method is easy to realize the online testing of the capacity of lead-acid battery. This sensor has many merits such as precise measurement, sensitive reaction, long-life use etc. It can be widely used in the electric capacity testing of the automobile lead-acid battery, the electric capacity testing of the industry lead-acid battery, liquor's concentration testing and salinity testing of the sea and have a bright future.

  2. Capacitive carbon and electrochemical lead electrode systems at the negative plates of lead-acid batteries and elementary processes on cycling

    NASA Astrophysics Data System (ADS)

    Pavlov, D.; Nikolov, P.

    2013-11-01

    Batteries in hybrid electric vehicles operate in High-Rate Partial-State-of-Charge (HRPSoC) cycling duty. To make lead-acid batteries suitable for this duty, carbon is added to the negative active material. As a result of this technological change, two electrical systems form at the negative plates: (a) a capacitive carbon system comprising high-rate charging and discharging of the electric double layer; low Ah capacity, and (b) a lead electrochemical system, comprising oxidation of Pb to PbSO4 during discharge and vice versa during charge; this system is slow to accept charge, but has high Ah capacity. Through cycling lead-acid cells under HRPSoC conditions with short current pulses of various durations we have established that the processes involved in the capacitive system proceed highly reversibly and complete hundreds of thousands HRPSoC cycles. The number of cycles achieved by the electrochemical system is limited to tens of thousands and lead to progressive sulfation. Carbon added to the negative active material changes the latter's structure. The specific surface of NAM increases and the median pore radius decreases. Some carbon additives may reduce the radius of the pores in NAM to membrane sizes, which may change the chemistry of the electrochemical system.

  3. "Lassie," "Toto," and fellow pet dogs: poised to lead the way for advances in cancer prevention.

    PubMed

    Knapp, Deborah W; Dhawan, Deepika; Ostrander, Elaine

    2015-01-01

    Cancer causes substantial morbidity and takes the lives of over 8 million people worldwide each year. Advances in cancer prevention research are crucial, and animal models are key to this. There are many valuable experimentally induced cancer models, but these do not fully meet the needs for cancer prevention studies. Pet dogs with risks for naturally occurring cancer can fill important gaps in cancer prevention research. Using invasive urothelial carcinoma (iUC) as an example, the advantages of utilizing pet dogs include: (1) close similarities between dogs and humans in carcinogenesis, molecular and cellular features, invasive and metastatic behavior, and response to treatment, thus providing high relevance for comparative studies, (2) shared environment between dogs and humans to help identify not-yet-known environmental iUC risks, (3) strong breed-associated risk (5- to 21-fold increased risk compared with mixed breeds) that facilitates investigation of gene-environment interactions, screening, and early intervention, (4) large size of dogs (versus rodents) that allows collection of fluids and tissues via cystoscopy, and detailed imaging at multiple time points, and (5) acceptance for studies in which each participating dog can benefit while enjoying life in their family environment, and in which findings will help other dogs and humans. An ongoing 3-year study in Scottish Terriers (comparable to a 15- to 20-year study in humans) is aimed at defining genetic and environmental risk factors for iUC, effective methods for screening/early detection, and a successful secondary cancer prevention approach with very promising results to date. Pet dogs can indeed propel cancer prevention research.

  4. Equilibrium II: Acids and Bases. Independent Learning Project for Advanced Chemistry (ILPAC). Unit P3.

    ERIC Educational Resources Information Center

    Inner London Education Authority (England).

    This unit on equilibrium is one of 10 first year units produced by the Independent Learning Project for Advanced Chemistry (ILPAC). The unit, which consists of two levels, focuses on the application of equilibrium principles to equilibria involving weak acids and bases, including buffer solutions and indicators. Level one uses Le Chatelier's…

  5. Mechanism of formation of dense anodic films of PbO on lead and lead alloys in sulfuric acid: Use of an {sup 18}O tracer

    SciTech Connect

    Rocca, E.; Steinmetz, J.; Weber, S.

    1999-01-01

    In order to elucidate the growth mechanism of the passive {alpha}-PbO at the interface grid/positive active material of the lead-acid batteries, a sequential electrochemical method using {sup 18}O was set up. It was established that the formation of a thick, dense PbO layer on pure lead and lead alloys (Pb-Sb, Pb-Ca-Sn), in potential conditions simulating deep discharged batteries for electric vehicles, is the consequence of a solid-state process, with O{sup 2{minus}} as the predominant diffusing species. Diffusion of O{sup 2{minus}} anions occurs along the grain boundaries of PbO, as well as in the grain bulk, probably between the two neighboring planes of Pb{sup 2+} cations of the PbO tetragonal structure.

  6. Recent advances in the solution of three-dimensional flow over wings with leading edge vortex separation

    NASA Technical Reports Server (NTRS)

    Johnson, F. T.; Tinoco, E. N.; Lu, P.; Epton, M. A.

    1979-01-01

    Recent advances in a panel method for the solution of three-dimensional flow about wing and wing-body combinations with leading-edge vortex separation are presented. These advances were achieved as part of an ultimately successful assault on two shortcomings of the method, namely convergence failures in seemingly random cases, and overprediction of lift coefficient for high aspect-ratio wings. Advances include the implementation of improved panel numerics for the purpose of eliminating the highly non-linear effects of ring vortices around doublet panel edges, and the development of a least squares procedure for damping vortex sheet geometry update instabilities. A variety of cases generated by the computer program implementing the method are presented. These cases are of two types. The first type consists of numerical studies, which verify the underlying mathematical assumptions of the method and moreover show that the results are strongly invariant with respect to such user dependent input as wing panel layout, initial sheet shape, sheet rollup, etc. The second type consists of cases run for the purpose of comparing computed results with experimental data, and these comparisons verify the underlying physical assumptions made by the method.

  7. Dietary Medium Chain Fatty Acid Supplementation Leads to Reduced VLDL Lipolysis and Uptake Rates in Comparison to Linoleic Acid Supplementation

    PubMed Central

    van Schalkwijk, Daniël B.; Pasman, Wilrike J.; Hendriks, Henk F. J.; Verheij, Elwin R.; Rubingh, Carina M.; van Bochove, Kees; Vaes, Wouter H. J.; Adiels, Martin; Freidig, Andreas P.; de Graaf, Albert A.

    2014-01-01

    Dietary medium chain fatty acids (MCFA) and linoleic acid follow different metabolic routes, and linoleic acid activates PPAR receptors. Both these mechanisms may modify lipoprotein and fatty acid metabolism after dietary intervention. Our objective was to investigate how dietary MCFA and linoleic acid supplementation and body fat distribution affect the fasting lipoprotein subclass profile, lipoprotein kinetics, and postprandial fatty acid kinetics. In a randomized double blind cross-over trial, 12 male subjects (age 51±7 years; BMI 28.5±0.8 kg/m2), were divided into 2 groups according to waist-hip ratio. They were supplemented with 60 grams/day MCFA (mainly C8:0, C10:0) or linoleic acid for three weeks, with a wash-out period of six weeks in between. Lipoprotein subclasses were measured using HPLC. Lipoprotein and fatty acid metabolism were studied using a combination of several stable isotope tracers. Lipoprotein and tracer data were analyzed using computational modeling. Lipoprotein subclass concentrations in the VLDL and LDL range were significantly higher after MCFA than after linoleic acid intervention. In addition, LDL subclass concentrations were higher in lower body obese individuals. Differences in VLDL metabolism were found to occur in lipoprotein lipolysis and uptake, not production; MCFAs were elongated intensively, in contrast to linoleic acid. Dietary MCFA supplementation led to a less favorable lipoprotein profile than linoleic acid supplementation. These differences were not due to elevated VLDL production, but rather to lower lipolysis and uptake rates. PMID:25049048

  8. Field Operations Program Chevrolet S-10 (Lead-Acid) Accelerated Reliability Testing - Final Report

    SciTech Connect

    J. Francfort; J. Argueta; M. Wehrey; D. Karner; L. Tyree

    1999-07-01

    This report summarizes the Accelerated Reliability testing of five lead-acid battery-equipped Chevrolet S-10 electric vehicles by the US Department of Energy's Field Operations Program and the Program's testing partners, Electric Transportation Applications (ETA) and Southern California Edison (SCE). ETA and SCE operated the S-10s with the goal of placing 25,000 miles on each vehicle within 1 year, providing an accelerated life-cycle analysis. The testing was performed according to established and published test procedures. The S-10s' average ranges were highest during summer months; changes in ambient temperature from night to day and from season-to-season impacted range by as much as 10 miles. Drivers also noted that excessive use of power during acceleration also had a dramatic effect on vehicle range. The spirited performance of the S-10s created a great temptation to inexperienced electric vehicle drivers to ''have a good time'' and to fully utilize the S-10's acceleration capability. The price of injudicious use of power is greatly reduced range and a long-term reduction in battery life. The range using full-power accelerations followed by rapid deceleration in city driving has been 20 miles or less.

  9. Accelerated cycle-life testing of small sealed lead/acid batteries

    NASA Astrophysics Data System (ADS)

    Kim, I.; Oh, S. H.; Kang, H. Y.

    An attempt has been made to devise methods for reducing the cycle-testing time of long-life sealed lead/acid batteries. In order for the accelerated test results to equate to the actual field operations, it is assumed that the failure modes under both normal and accelerated conditions must be the same. As a first step in the search for a reliable accelerated test, observations of the battery ageing process have been made under different daily duty cycles, viz., 1 (normal), 8 and 16 cycles/day at ambient temperature and 80% depth-of-discharge. It has been found that the main cause of failure is different for a given duty cycle. This complicates the task of applying accelerated test results to field operations. For the 8 cycles/day schedule, the main cause of failure is degradation of the positive active material. Positive grid corrosion is the main factor in the 16 cycles/day case. Under normal conditions, both grid corrosion and PbO 2 degradation appear to be equally significant.

  10. Investigating the use of porous, hollow glass microspheres in positive lead acid battery plates

    NASA Astrophysics Data System (ADS)

    Sorge, Matthew; Bean, Thomas; Woodland, Travis; Canning, John; Cheng, I. Frank; Edwards, Dean B.

    2014-11-01

    Porous, hollow, glass microspheres (PHGMs) can be used to increase porosity in lead acid battery electrodes to improve the battery's power and energy performance at higher discharge rates. As reported in this paper, the PHGM additives did improve electrolyte storage and porosity in the electrodes. However, the nonconductive PHGMs do reduce the critical volume fraction (CVF) of the electrodes as predicted from conductivity models. The increase in electrode performance due to increased porosity may therefore be partially offset by the drop in capacity due to a lower critical volume fraction. Empirical equations are developed that relate the CFV and porosity of an electrode to the amount, size, and porosity of the additives in that electrode. The porosity estimates made from the empirical equations compare favorably with the experimental data from plates fabricated with these additives. The performance of electrodes with additives is estimated from computer models using the electrode's CVF and porosity as provided by the equations. Tests were performed on plates having volume loadings of PHGMs from 11% to 44% of total solids in positive electrodes to determine their effect on active material utilizations. The results from these discharge tests are reported and compared with theoretical models.

  11. Fuzzy modelling for the state-of-charge estimation of lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Burgos, Claudio; Sáez, Doris; Orchard, Marcos E.; Cárdenas, Roberto

    2015-01-01

    This paper introduces a novel fuzzy model based structure for the characterisation of discharge processes in lead-acid batteries. This structure is based on a fuzzy model that characterises the relationship between the battery open-circuit voltage (Voc), the state of charge (SoC), and the discharge current. The model is identified and validated using experimental data that is obtained from an experimental system designed to test battery banks with several charge/discharge profiles. For model identification purposes, two standard experimental tests are implemented; one of these tests is used to identify the Voc-SoC curve, while the other helps to identify additional parameters of the model. The estimation of SoC is performed using an Extended Kalman Filter (EKF) with a state transition equation that is based on the proposed fuzzy model. Performance of the proposed estimation framework is compared with other parametric approaches that are inspired on electrical equivalents; e.g., Thevenin, Plett, and Copetti.

  12. Evolution of internal resistance during formation of flooded lead-acid batteries

    NASA Astrophysics Data System (ADS)

    White, Chris; Deveau, Justin; Swan, Lukas G.

    2016-09-01

    This study employs experimental techniques to measure the changing internal resistance of flooded, flat-plate lead-acid batteries during container formation, revealing a novel indicator of formation completeness. In order to measure internal resistance during formation, d.c. current pulses are superimposed over the constant formation current at set intervals, while change in voltage is measured. The resulting "pulsed" internal resistance is divided into ohmic and interfacial components by measuring the ohmic resistance with short d.c. pulses as well as with a.c. injection. Various constant-current container formations are carried out using different current levels, plate thicknesses, and pulsing techniques, yielding an array of resistance trends which are explained using Butler-Volmer kinetic theory. Ohmic and interfacial resistance trends are shown both theoretically and experimentally to eventually decay to a predictable steady-state value as the formation proceeds, suggesting that this internal resistance method can be used to detect the completion of the formation. The same principles are shown to apply to recharge cycles as well, but with potentially limited practical implications in comparison to formation.

  13. Photocatalytic hydrogen generation from hydriodic acid using methylammonium lead iodide in dynamic equilibrium with aqueous solution

    NASA Astrophysics Data System (ADS)

    Park, Sunghak; Chang, Woo Je; Lee, Chan Woo; Park, Sangbaek; Ahn, Hyo-Yong; Nam, Ki Tae

    2017-01-01

    The solar-driven splitting of hydrohalic acids (HX) is an important and fast growing research direction for H2 production. In addition to the hydrogen, the resulting chemicals (X2/X3-) can be used to propagate a continuous process in a closed cycle and are themselves useful products. Here we present a strategy for photocatalytic hydrogen iodide (HI) splitting using methylammonium lead iodide (MAPbI3) in an effort to develop a cost-effective and easily scalable process. Considering that MAPbI3 is a water-soluble ionic compound, we exploit the dynamic equilibrium of the dissolution and precipitation of MAPbI3 in saturated aqueous solutions. The I- and H+ concentrations of the aqueous solution are determined to be the critical parameters for the stabilization of the tetragonal MAPbI3 phase. Stable and efficient H2 production under visible light irradiation was demonstrated. The solar HI splitting efficiency of MAPbI3 was 0.81% when using Pt as a cocatalyst.

  14. Resolution in QCM sensors for the viscosity and density of liquids: application to lead acid batteries.

    PubMed

    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.

  15. Measurement of stibine and arsine generation from the Exide 3100-AH lead-acid module

    NASA Astrophysics Data System (ADS)

    Marr, J. J.; Smaga, J. A.

    1987-01-01

    Stibine and arsine evolution from lead-acid cells in a 36-kWh Exide load-leveling module was measured as this module approached 1900 cycles of operation. A specially prepared gas-collection apparatus enabled us to determine the maximum and average rates for evolution of both toxic hydrides. Hydride generation began once the cell voltage exceeded 2.4 V. The maximum rate for arsine occurred just above 2.5 V and consistently preceded the peak rate for stibine for each sampled cell. When adjusted for size effects, the degree of stibine and arsine evolution was greater than found in a continuous overcharge study conducted by Exide. The average rates of hydride generation were found to be 175 microgram/min for stibine and 12.6 microgram/min for arsine. The former rate proved to be the critical value in determining safe ventilation requirements for cell off-gases. The minimum airflow requirement was calculated to be 340 L/min per cell. Projections for a hypothetical 1-MWh Exide battery without an abatement system indicated that the normal ventilation capacity in the Battery Energy Storage Test facility provides nearly five times the airflow needed for safe hydride removal.

  16. The use of castor oil and ricinoleic acid in lead chalcogenide nanocrystal synthesis

    NASA Astrophysics Data System (ADS)

    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.

  17. [Advances in the progress of anti-bacterial biofilms properties of acetic acid].

    PubMed

    Gao, Xinxin; Jin, Zhenghua; Chen, Xinxin; Yu, Jia'ao

    2016-06-01

    Bacterial biofilms are considered to be the hindrance in the treatment of chronic wound, because of their tolerance toward antibiotics and other antimicrobial agents. They also have strong ability to escape from the host immune attack. Acetic acid, as a kind of organic weak acid, can disturb the biofilms by freely diffusing through the bacterial biofilms and bacterial cell membrane structure. Then the acid dissociates to release the hydrogen ions, leading to the disorder of the acid-base imbalance, change of protein conformation, and the degradation of the DNA within the membranes. This paper reviews the literature on the characteristics and treatment strategies of the bacterial biofilms and the acetic acid intervention on them, so as to demonstrate the roles acetic acid may play in the treatment of chronic wound, and thus provide a convincing treatment strategy for this kind of disease.

  18. Potassium-competitive acid blockers: Advanced therapeutic option for acid-related diseases.

    PubMed

    Inatomi, Nobuhiro; Matsukawa, Jun; Sakurai, Yuuichi; Otake, Kazuyoshi

    2016-12-01

    Acid-related diseases (ARDs), such as peptic ulcers and gastroesophageal reflux disease, represent a major health-care concern. Some major milestones in our understanding of gastric acid secretion and ARD treatment reached during the last 50years include 1) discovery of histamine H2-receptors and development of H2-receptor antagonists, 2) identification of H(+),K(+)-ATPase as the parietal cell proton pump and development of proton pump inhibitors (PPIs), and 3) identification of Helicobacter pylori (H. pylori) as the major cause of peptic ulcers and development of effective eradication regimens. Although PPI treatments have been effective and successful, there are limitations to their efficacy and usage, i.e. short half-life, insufficient acid suppression, slow onset of action, and large variation in efficacy among patients due to CYP2C19 metabolism. Potassium-competitive acid blockers (P-CABs) inhibit H(+),K(+)-ATPase in a reversible and K(+)-competitive manner, and exhibit almost complete inhibition of gastric acid secretion from the first dose. Many pharmaceutical companies have tried to develop P-CABs, but most of their clinical development has been discontinued due to safety concerns or a similar efficacy to PPIs. Revaprazan was developed in Korea and was the first P-CAB approved for sale. Vonoprazan, approved in 2014 in Japan, has a completely different chemical structure and higher pKa value compared to other P-CABs, and exhibits rapid onset of action and prolonged control of intragastric acidity. Vonoprazan is an effective treatment for ARDs that is especially effective in healing reflux esophagitis and for H. pylori eradication. P-CABs, such as vonoprazan, promise to further improve the management of ARDs.

  19. Therapeutic efficiency of succimer used with calcium and ascorbic acid in the treatment of mild lead-poisoning.

    PubMed

    Jin, Yaping; Yu, Fei; Liao, Yingjun; Liu, Shaoxia; Liu, Meimei; Xu, Jianhong; Yang, Jun

    2011-01-01

    The aim of this study was to explore therapeutic efficiency of succimer used with calcium and ascorbic acid in the treatment of mildly lead-poisoned mice and preschool children. Mice were exposed to lead by drinking water, and then treated with saline solution, 50mg/kg body weight (b.w.) succimer, 100mg/kg b.w. succimer, or 50mg/kg b.w. succimer plus calcium and ascorbic acid by gavage. Seventy-two children aged 48-72 months were randomly assigned into combined treatment or nutritional intervention group. Lead levels in blood and bone were analyzed by atomic absorption spectrophotometry. Activities of aminolevulinic acid dehydratase (ALAD) in blood were determined by colorimetric method. Results of animal experiment showed that succimer used alone could reduce lead levels in blood and bone and reverse activities of ALAD in blood, however, a better therapeutic efficiency in mobilizing bone lead could be achieved by succimer used with calcium and ascorbic acid. Findings from the clinical study showed that reduction of blood lead levels (BLLs) between the end and initiation of therapy in the combined treatment group was significantly greater than that in the nutritional intervention group. Percentage of children with BLLs less than 10μg/dL at the end of therapy and the eighth week after therapy in the combined treatment group was significantly higher than that in the nutritional intervention group. In conclusion, combined use of succimer with calcium and ascorbic acid seemed to be a choice in the treatment of mildly lead poisoned children.

  20. Case Report: Valproic Acid and Risperidone Treatment Leading to Development of Hyperammonemia and Mania

    ERIC Educational Resources Information Center

    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…

  1. [Measurement of lead in high-salt food with sulfuric-nitric acid to treat food ash].

    PubMed

    Shi, Y; Zhang, Y; Wang, Y

    2001-03-01

    Lead in high-salt food was measured by treating the ash with sulfuric-nitric acid, and diluting lead standard with sodium sulfate to eliminate the disturbance of chloride in detecting lead with atomic absorption spectrophotometry. The minimum detection limit was 0.10 mg/kg. The relative standard deviation is 1.72%, 5.00% and 7.14% while the amount of lead was 8.70, 2.40 and 1.40 micrograms respectively. The recovery varied between 90.0%-109.0%. There was no significant difference (P > 0.05) of the lead content between the mentioned method and extraction flame photometry. The amount of lead is higher obviously than that of other two methods by eliminating the disturbance of chloride. The method was simple, precise and accurate, and suitable for hygienic examination.

  2. Influence of the active mass particle suspension in electrolyte upon corrosion of negative electrode of a lead-acid battery

    NASA Astrophysics Data System (ADS)

    Kamenev, Yu.; Shtompel, G.; Ostapenko, E.; Leonov, V.

    2014-07-01

    The influence of the suspension of positive active mass particles in the electrolyte on the performance of the negative electrode in a lead-acid battery is studied. A significant increase in the rate of corrosion of the lead electrode is shown when slime particles get in contact with its surface, which may result in the rise of macro-defects on the lugs of the negative electrodes.

  3. A polymorphism in the delta-aminolevulinic acid dehydratase gene may modify the pharmacokinetics and toxicity of lead.

    PubMed Central

    Smith, C M; Wang, X; Hu, H; Kelsey, K T

    1995-01-01

    Associations between the presence of a constitutional variant of delta-aminolevulinic acid dehydratase (ALAD-2) and lead concentrations in blood and bone, as well as between this allele and indices of kidney function, were investigated among 691 members of a construction trade union. The average blood lead level in this group was 7.78 micrograms/dl. No significant difference was observed in blood lead concentration in ALAD-2 carriers compared to those homozygous for the more common ALAD-1 allele (7.78 +/- 3.62 micrograms Pb/dl vs. 7.73 ( +/- 3.48 micrograms Pb/dl, respectively; p = 0.73). Bone lead was measured in a subset of 122 of the study subjects. Patella minus tibia lead concentrations for each individual averaged 3.35 +/- 11.99 micrograms Pb/g bone mineral in ALAD-1 homozygotes and 8.62 +/- 9.47 micrograms Pb/g bone mineral in ALAD-2 carriers (p = 0.06). Comparisons of blood urea nitrogen (BUN) and uric acid by genotype indicated elevated levels among ALAD-2 individuals (p = 0.03 and 0.07, respectively). In logistic regression models accounting for other variables potentially associated with BUN and uric acid levels, BUN was significantly associated with blood lead levels (p = 0.01). Associations of BUN and uric acid levels with ALAD-2 were of borderline statistical significance in these models (p = 0.06 and 0.07). Taken together, these results suggest that the ALAD-2 genotype may influence the pharmacokinetic distribution and chronic renal toxicity of lead, perhaps due to differential binding of lead to the variant protein. Images p248-a Figure 1. PMID:7768225

  4. Zoledronic acid in metastatic chondrosarcoma and advanced sacrum chordoma: two case reports

    PubMed Central

    Montella, Liliana; Addeo, Raffaele; Faiola, Vincenzo; Cennamo, Gregorio; Guarrasi, Rosario; Capasso, Elena; Mamone, Rosanna; Michele, Caraglia; Del Prete, Salvatore

    2009-01-01

    Introduction Chondrosarcomas and chordomas are usually chemoresistant bone tumors and may have a poor prognosis when advanced. They are usually associated with worsening pain difficult to control. Patients and Methods Zoledronic acid was used in a 63-year-old man with metastatic chondrosarcoma and in a 66-year-old woman with a diagnosis of sacrum chordoma both reporting severe pain related to tumor. Results In the first case, zoledronic acid was able to maintain pain control despite disease progression following chemotherapy, in the other case, zoledronic acid only produced significant clinical benefit. Conclusion Control of pain associated with bone tumors such as chondrosarcoma and chondroma may significantly improve from use of zoledronic acid, independently from tumor response to other treatments. Evaluation on larger series are needed to confirm the clinical effect of this bisphosphonate on such tumors. PMID:19144109

  5. Gene Therapy for Advanced Melanoma: Selective Targeting and Therapeutic Nucleic Acids

    PubMed Central

    Viola, Joana R.; Rafael, Diana F.; Wagner, Ernst; Besch, Robert; Ogris, Manfred

    2013-01-01

    Despite recent advances, the treatment of malignant melanoma still results in the relapse of the disease, and second line treatment mostly fails due to the occurrence of resistance. A wide range of mutations are known to prevent effective treatment with chemotherapeutic drugs. Hence, approaches with biopharmaceuticals including proteins, like antibodies or cytokines, are applied. As an alternative, regimens with therapeutically active nucleic acids offer the possibility for highly selective cancer treatment whilst avoiding unwanted and toxic side effects. This paper gives a brief introduction into the mechanism of this devastating disease, discusses the shortcoming of current therapy approaches, and pinpoints anchor points which could be harnessed for therapeutic intervention with nucleic acids. We bring the delivery of nucleic acid nanopharmaceutics into perspective as a novel antimelanoma therapeutic approach and discuss the possibilities for melanoma specific targeting. The latest reports on preclinical and already clinical application of nucleic acids in melanoma are discussed. PMID:23634303

  6. Effects of dietary sulfur amino acids on lead toxicity in chicks

    SciTech Connect

    Latta, D.M.

    1986-01-01

    Factorial experiments were conducted to examine the interactions of dietary methionine with cystine, choline and glycine in lead (Pb) intoxicated chicks. In Experiment 1, chicks were fed a basal diet deficient in methionine and total sulfur-containing amino acids (SAA) with 0 or 1000 ppm added Pb. Methionine or methionine plus cystine improved growth regardless of Pb level; cystine addition alone improved growth only when Pb was present. Dietary methionine appeared to counteract Pb toxicity more effectively than cystine. In Experiments 2 and 3 dietary variables were 0 or 1000 ppm Pb, adequate or inadequate methionine and marginal or excess (Experiment 2) or adequate or inadequate (Experiment 3) choline. In Experiment 2 growth depression by Pb was less with methionine-adequate compared to methionine-inadequate diets; there were no differences in growth with choline-marginal or choline-excess diets. In Experiment 3, the Pb-induced growth depression was exacerbated by adequate choline when methionine-inadequate diets were fed. It appears that Pb lowers the chick's choline requirement and that the methyl moiety of methionine does not participate directly in Pb detoxification. In Experiment 4 effects of adequate or deficient methionine, adequate or excess glycine and 0 or 1000 ppm Pb in choline-deficient chicks were studied. Methionine stimulated growth and the response was greater when excess glycine was present. Excess glycine stimulated growth only in the presence of adequate methionine suggesting glycine is limiting for growth in choline-deficient, methionine-adequate diets. These studies indicate that adequate methionine ameliorates Pb-induced growth depression in growing chicks but that the methionine effect is greater with choline-adequate than with choline-deficient diets. The amelioration of Pb toxicity by methionine may be partly related to increased excretion of Pb.

  7. The behaviour of the coup de fouet of valve-regulated lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Pascoe, Phillip E.; Anbuky, Adnan H.

    This paper presents the results of an investigation into the initial stage of the discharge voltage response of valve-regulated lead-acid (VRLA) batteries. This region is dominated by the phenomenon known as the coup de fouet which manifests itself as a voltage dip followed by a recovery. The research focuses on two parameters found within the coup de fouet region, namely, the trough and the plateau voltage. It is found that these parameters are influenced by the operating conditions and the sate-state-of health (SoH) of the battery. The operating conditions considered are discharge rate, ambient temperature, depth of previous discharge, charge duration, and float voltage. The coup de fouet parameters corresponding to high rate discharges, as well as discharges conducted at low temperatures, have reduced magnitudes compared with those conducted at lower rates or higher temperatures. This behaviour mirrors the availability of capacity when the battery is discharged under the same operating conditions. The float voltage is found to have a direct relationship with the trough and plateau voltages, whereas an indirect relationship between charge duration and the trough and plateau voltages is observed. The influence of variations in discharge depth on the coup de fouet is more complex. For consecutive discharge depths below approximately 10% of rated capacity, the coup de fouet becomes distorted and exhibits a second voltage dip. For consecutive discharges of greater depth, this does not occur. The influence of the degradation in battery SoH due to accelerated thermal ageing, water replenishment post-accelerated thermal ageing, and field ageing is investigated. The coup de fouet parameters associated with the discharge of batteries with low SoH have a reduced magnitude compared with those associated with the discharge of batteries with a high SoH.

  8. Role of ethylenediaminetetraacetic acid on lead uptake and translocation by tumbleweed (salsola kali L.).

    PubMed

    de la Rosa, Guadalupe; Peralta-Videa, Jose R; Cruz-Jimenez, Gustavo; Duarte-Gardea, M; Martinez-Martinez, Alejandro; Cano-Aguilera, Irene; Sharma, Nilesh C; Sahi, Shivendra V; Gardea-Torresdey, Jorge L

    2007-05-01

    Tumbleweed plants (Salsola kali L.) grown in agar and liquid media demonstrated a high capacity to accumulate Pb in their different parts without affecting biomass. Whereas shoot elongation and biomass were not significantly affected by high tissue concentrations of Pb, root growth was significantly affected relative to controls. Roots, stems, and leaves demonstrated Pb concentrations of 31,000, 5,500, and 2,100 mg/kg dry weight, respectively, when plants were grown in the agar medium containing 80 mg Pb/L. Application of ethylenediaminetetraacetic acid (EDTA) to Pb-contaminated media dramatically reduced the total acquisition of Pb from both types of media. However, EDTA significantly increased the translocation of Pb from roots to the aerial parts, as evidenced by a multifold increase (23- and 155-fold for agar and liquid media, respectively) in the translocation concentration factor. The concentration of the antioxidant thiol compounds significantly increased (p < 0.05) in plants grown with uncomplexed Pb treatments relative to control plants. Scanning-electron microscopy and electron dispersive x-ray spectroscopic evaluation of leaf samples demonstrated an interesting pattern of Pb translocation in the presence or absence of EDTA. Large Pb crystals were found across the leaf tissues (palisade, spongy parenchyma, and conducting tissues) in the absence of EDTA. Lead nanoparticles also were seen when plants were grown in Pb-EDTA solution. Ultramicroscopic features of tumbleweed provide clear evidence for the unrestricted conduction of Pb from the root to the aerial parts, and this property makes the plant a good candidate for phytoremediation.

  9. Neuroprotective Actions of Clinoptilolite and Ethylenediaminetetraacetic Acid Against Lead-induced Toxicity in Mice Mus musculus

    PubMed Central

    Basha, Mahaboob P.; Begum, Shabana; Mir, Bilal Ahmed

    2013-01-01

    Objectives: Oxidative stress is considered as a possible molecular mechanism involved in lead (Pb2+) neurotoxicity. Very few studies have been investigated on the occurrence of oxidative stress in developing animals due to Pb2+ exposure. Considering the vulnerability of the developing brain to Pb2+, this study was carried out to investigate the effects of Pb2+ exposure in brain regions especially on antioxidant enzyme activities along with ameliorative effects of ethylenediaminetetraacetic acid (EDTA) and clinoptilolite. Methods: Three-week old developing Swiss mice Mus musculus were intraperitoneally administered with Pb2+ acetate in water (w/v) (100 mg/kg body weight/day) for 21 days and control group was given distilled water. Further Pb2+-toxicated mice were made into two subgroups and separately supplemented with EDTA and clinoptilolite (100 mg/kg body weight) for 2 weeks. Results: In Pb2+-exposed mice, in addition to increased lipid peroxidation, the activity levels of catalase, superoxide dismutase (SOD), glutathione peroxidase (GPx), and glutathione (GSH) found to decrease in all regions of brain indicating, existence of severe oxidative stress due to decreased antioxidant function. Treatment of Pb2+-exposed mice with EDTA and clinoptilolite lowered the lipid peroxidation (LPO) levels revealing their antioxidant potential to prevent oxidative stress. Similarly their administration led to recover the level of catalase, SOD, and GPx enzymes affected during Pb2+ toxicity in different regions of brain. Conclusions: The protection of brain tissue against Pb2+-induced toxicity by clinoptilolite and EDTA in the present experiment might be due to their ability to react faster with peroxyl radicals there by reducing the severity of biochemical variable indicative of oxidative damage. Thus, the results of present study indicate the neuroprotective potential of clinoptilolite and EDTA against Pb2+ toxicity. PMID:24403728

  10. Microstructural Developments Leading to New Advanced High Strength Sheet Steels: A Historical Assessment of Critical Metallographic Observations

    SciTech Connect

    Matlock, David K

    2015-08-03

    In the past 30+ years significant advancements have been made in the development of higher strength sheet steels with improved combinations of strength and ductility that have enabled important product improvements leading to safer, lighter weight, and more fuel efficient automobiles and in other applications. Properties of the primarily low carbon, low alloy steels are derived through careful control of time-temperature processing histories designed to produce multiphase ferritic based microstructures that include martensite and other constituents including retained austenite. The basis for these developments stems from the early work on dual-phase steels which was the subject of much interest. In response to industry needs, dual-phase steels have evolved as a unique class of advanced high strength sheet steels (AHSS) in which the thermal and mechanical processing histories have been specifically designed to produce constituent combinations for the purpose of simultaneously controlling strength and deformation behavior, i.e. stress-strain curve shapes. Improvements continue as enhanced dual-phase steels have recently been produced with finer microstructures, higher strengths, and better overall formability. Today, dual phase steels are the primary AHSS products used in vehicle manufacture, and several companies have indicated that the steels will remain as important design materials well into the future. In this presentation, fundamental results from the early work on dual-phase steels will be reviewed and assessed in light of recent steel developments. Specific contributions from industry/university cooperative research leading to product improvements will be highlighted. The historical perspective provided in the evolution of dual-phase steels represents a case-study that provides important framework and lessons to be incorporated in next generation AHSS products.

  11. Preparing ultrafine PbS powders from the scrap lead-acid battery by sulfurization and inert gas condensation

    NASA Astrophysics Data System (ADS)

    Xia, Huipeng; Zhan, Lu; Xie, Bing

    2017-02-01

    A novel method for preparing ultrafine PbS powders involving sulfurization combined with inert gas condensation is developed in this paper, which is applicable to recycle Pb from lead paste of spent lead-acid batteries. Initially, the effects of the evaporation and condensation temperature, the inert gas pressure, the condensation distance and substrate on the morphology of as-obtained PbS ultrafine particles are intensively investigated using sulfur powders and lead particles as reagents. Highly dispersed and homogeneous PbS nanoparticles can be prepared under the optimized conditions which are 1223 K heating temperature, 573 K condensation temperature, 100 Pa inert gas pressure and 60 cm condensation distance. Furthermore, this method is successfully applied to recycle Pb from the lead paste of spent lead acid battery to prepare PbS ultrafine powders. This work does not only provide the theoretical fundamental for PbS preparation, but also provides a novel and efficient method for recycling spent lead-acid battery with high added-value products.

  12. Can the Institute of Medicine trump the dominant logic of nursing? Leading change in advanced practice education.

    PubMed

    Dreher, Melanie C; Clinton, Patricia; Sperhac, Arlene

    2014-01-01

    The Institute of Medicine (IOM; 2010) has called for a transformation of the nursing profession to lead the redesign of health care in the United States. It acknowledges the need for profound change in nursing education, particularly advanced practice education, to produce the next generation of leaders in sufficient quantity to expand access, improve quality, and reduce cost. Although the IOM provides welcome validation of nursing's significant role, most of the recommendations are not new and have been advocated by nurse educators for decades. What has prevented us from creating the nimble and responsive educational programs that would ensure a sufficient corpus of advanced practice nurses with the relevant knowledge and skill to transform our ailing health system? Conceptualizing nursing as a complex, adaptive system (J.W. Begun and K. White, 1997), this article explores three examples of the dominant logic, grounded in a historical legacy that has kept the nursing profession from realizing its promise as a potent force: (a) the continuing preference for experience over education, (b) the belief that only nurses can teach nurses, and (c) the hegemony of the research doctorate.

  13. Strong topographic sheltering effects lead to spatially complex treeline advance and increased forest density in a subtropical mountain region.

    PubMed

    Greenwood, Sarah; Chen, Jan-Chang; Chen, Chaur-Tzuhn; Jump, Alistair S

    2014-12-01

    Altitudinal treelines are typically temperature limited such that increasing temperatures linked to global climate change are causing upslope shifts of treelines worldwide. While such elevational increases are readily predicted based on shifting isotherms, at the regional level the realized response is often much more complex, with topography and local environmental conditions playing an important modifying role. Here, we used repeated aerial photographs in combination with forest inventory data to investigate changes in treeline position in the Central Mountain Range of Taiwan over the last 60 years. A highly spatially variable upslope advance of treeline was identified in which topography is a major driver of both treeline form and advance. The changes in treeline position that we observed occurred alongside substantial increases in forest density, and lead to a large increase in overall forest area. These changes will have a significant impact on carbon stocking in the high altitude zone, while the concomitant decrease in alpine grassland area is likely to have negative implications for alpine species. The complex and spatially variable changes that we report highlight the necessity for considering local factors such as topography when attempting to predict species distributional responses to warming climate.

  14. The Effect of Ascorbic Acid and Garlic Administration on Lead-Induced Apoptosis in Rat Offspring's Eye Retina

    PubMed Central

    Khordad, Elnaz; Fazel, Alireza; Ebrahimzadeh Bideskan, Alireza

    2013-01-01

    Introduction: Lead toxicity induces retinal cell apoptosis. Vitamin C and garlic may decrease lead-induced apoptosis. This study was undertaken to investigate vitamin C and garlic protective effects on lead-induced apoptosis in eye retina. Methods: Pregnant Wistar rats (n = 72) were divided randomly into 9 groups: (L) treated rats with lead acetate in drinking water and (L+AA) with leaded water and vitamin C intraperitoneally;(L+G), the rats received leaded-water and garlic juice via gavage; (L+AA+G) treated rats with leaded water, ascorbic acid, and garlic juice, (AA) with ascorbic acid, and (G) with garlic juice; (AA+G) treated rats with vitamin C and garlic juice and (Sh) with tap water plus normal hydrogen chloride (HCl) and glucose; normal (N). After 21-day lactation, blood lead level (BLL) in rats was measured, and then their offspring and the rat offspring's eyes were removed and processed for using TUNEL method. TUNEL positive cells in the eye retina were counted and all groups were compared. Results: BLL increased in L group compared to the control groups and decreased significantly in L + G, L + AA, and L+ AA + G groups compared to L group (P<0.05). TUNELL positive cell number in eye retina significantly increased in L group compared to control groups (P<0.05) and decreased in L+ G, L+ AA, and L+AA + G groups compared to L group (P<0.05). Conclusion: Garlic juice and ascorbic acid administration during pregnancy and lactation may protect lead-induced apoptosis in rat offspring's eye retina. PMID:23999717

  15. Effects of advanced oxidation pretreatment on residual aluminum control in high humic acid water purification.

    PubMed

    Wang, Wendong; Li, Hua; Ding, Zhenzhen; Wang, Xiaochang

    2011-01-01

    Due to the formation of disinfection by-products and high concentrations of Al residue in drinking water purification, humic substances are a major component of organic matter in natural waters and have therefore received a great deal of attention in recent years. We investigated the effects of advanced oxidation pretreatment methods usually applied for removing dissolved organic matters on residual Al control. Results showed that the presence of humic acid increased residual Al concentration notably. With 15 mg/L of humic acid in raw water, the concentrations of soluble aluminum and total aluminum in the treated water were close to the quantity of Al addition. After increasing coagulant dosage from 12 to 120 mg/L, the total-Al in the treated water was controlled to below 0.2 mg/L. Purification systems with ozonation, chlorination, or potassium permanganate oxidation pretreatment units had little effects on residual Al control; while UV radiation decreased Al concentration notably. Combined with ozonation, the effects of UV radiation were enhanced. Optimal dosages were 0.5 mg O3/mg C and 3 hr for raw water with 15 mg/L of humic acid. Under UV light radiation, the combined forces or bonds that existed among humic acid molecules were destroyed; adsorption sites increased positively with radiation time, which promoted adsorption of humic acid onto polymeric aluminum and Al(OH)3(s). This work provides a new solution for humic acid coagulation and residual Al control for raw water with humic acid purification.

  16. L-ascorbic acid and α tocopherol supplementation and antioxidant status in nickel- or lead-exposed rat brain tissue.

    PubMed

    Das, Kusal K; Saha, Sikha

    2010-01-01

    We evaluated the effect of L-ascorbic acid and alpha-tocopherol supplementation on plasma and whole brain nitric oxide level and antioxidant status in nickel sulfate- or lead acetate- treated male albino rats. Nitric oxide and lipid peroxide levels in whole brain tissue and plasma increased following nickel and lead treatment but significantly returned to near-normal values upon L-ascorbic acid or alpha-tocopherol supplementation. In brain tissue, antioxidant enzymes--superoxide dismutase, glutathione peroxidase, glutathione peroxidase, and catalase--along with the glutathione level decreased significantly after both treatments but significantly improved upon simultaneous supplementation with L-ascorbic acid or alpha-tocopherol. Lead-treated animals showed a greater improvement with alpha-tocopherol, whereas nickel-treated rats showed a greater improvement with L-ascorbic acid. In both groups, combined supplementation with L-ascorbic acid and alpha-tocopherol did not change the percentage improvement in comparison with supplementation with a single vitamin alone.

  17. Injury Surveillance and Safety Considerations for Large-Format Lead-Acid Batteries Used in Mining Applications

    PubMed Central

    Reyes, Miguel Angel; Novak, Thomas

    2016-01-01

    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. PMID:27784953

  18. Recent advances in the biomedical applications of fumaric acid and its ester derivatives: The multifaceted alternative therapeutics.

    PubMed

    Das, Ratul Kumar; Brar, Satinder Kaur; Verma, Mausam

    2016-04-01

    Several lines of evidence have demonstrated the potential biomedical applications of fumaric acid (FA) and its ester derivatives against many human disease conditions. Fumaric acid esters (FAEs) have been licensed for the systemic treatment of the immune-mediated disease psoriasis. Biogen Idec Inc. announced about the safety and efficacy of the formulation FAE (BG-12) for treating RRMS (relapsing-remitting multiple sclerosis). Another FAE formulation DMF (dimethyl fumarate) was found to be capable of reduction in inflammatory cardiac conditions, such as autoimmune myocarditis and ischemia and reperfusion. DMF has also been reported to be effective as a potential neuroprotectant against the HIV-associated neurocognitive disorders (HAND). Many in vivo studies carried out on rat and mice models indicated inhibitory effects of fumaric acid on carcinogenesis of different origins. Moreover, FAEs has emerged as an important matrix ingredient in the fabrication of biodegradable scaffolds for tissue engineering applications. Drug delivery vehicles composed of FAEs have shown promising results in delivering some leading drug molecules. Apart from these specific applications and findings, many more studies on FAEs have revealed new therapeutic potentials with the scope of clinical applications. However, until now, this scattered vital information has not been written into a collective account and analyzed for minute details. The aim of this paper is to review the advancement made in the biomedical application of FA and FAEs and to focus on the clinical investigation and molecular interpretation of the beneficial effects of FA and FAEs.

  19. Effects of lead exposure on the status of platelet indices in workers involved in a lead-acid battery manufacturing plant.

    PubMed

    Barman, Tapu; Kalahasthi, Ravibabu; Rajmohan, H R

    2014-11-01

    This study was carried out to determine the effect of Pb exposure on the status of platelet indices in workers exposed to Pb during lead-acid battery plant process. Platelet indices and blood lead levels (BLLs) were determined in 429 male workers. BLLs were determined by using an atomic absorption spectrophotometer. Platelet indices in the samples were quantified by using the Sysmex KX-21 hematology analyzer. The levels of platelet count (PLT), plateletcrit (PCT) and mean platelet mass (MPM) were significantly decreased and platelet distribution width (PDW), platelet large cell ratio (P-LCR) and mean platelet volume were increased with an increase in BLLs. The results of linear multiple regression analysis showed that the platelet count (β -0.143, P=0.005), PCT (β -0.115, P=0.023) and MPM (β -0.110, P=0.030) were negatively associated with BLLs and P-LCR (β 0.122, P=0.016) was positively associated with BLLs. The variable of body mass index showed a positive association with PCT (β 0.105, P=0.032) and MPM (β 0.101, P=0.039). The results of the study may indicate that lead exposure may impair coagulation function through endothelial tissue injury and reduction of nitric oxide.

  20. Investigations of the pore formation in the lead selenide films using glacial acetic acid- and nitric acid-based electrolyte

    PubMed Central

    2012-01-01

    We report a novel synthesis of porous PbSe layers on Si substrates by anodic electrochemical treatment of PbSe/CaF2/Si(111) epitaxial structures in an electrolyte solution based on glacial acetic acid and nitric acid. Electron microscopy, X-ray diffractometry, and local chemical microanalysis investigation results for the porous layers are presented. Average size of the synthesized mesopores with approximately 1010 cm−2 surface density was determined to be 22 nm. The observed phenomenon of the active selenium redeposition on the mesopore walls during anodic treatment is discussed. PMID:22726822

  1. Investigations of the pore formation in the lead selenide films using glacial acetic acid- and nitric acid-based electrolyte.

    PubMed

    Zimin, Sergey P; Gorlachev, Egor S; Naumov, Viktor V; Skok, Fedor O

    2012-01-01

    We report a novel synthesis of porous PbSe layers on Si substrates using anodic electrochemical treatment of PbSe/CaF2/Si(111) epitaxial structures in an electrolyte solution based on glacial acetic acid and nitric acid. Electron microscopy, x-ray diffractometry, and local chemical microanalysis investigations results for the porous layers are presented. Average size of the synthesized mesopores with ~1010 cm-2 surface density was determined to be 22 nm. The observed phenomenon of the active selenium redeposition on the mesopore walls during anodic treatment is discussed.

  2. Advances in polymeric and inorganic vectors for nonviral nucleic acid delivery

    PubMed Central

    Sunshine, Joel C; Bishop, Corey J; Green, Jordan J

    2014-01-01

    Nonviral systems for nucleic acid delivery offer a host of potential advantages compared with viruses, including reduced toxicity and immunogenicity, increased ease of production and less stringent vector size limitations, but remain far less efficient than their viral counterparts. In this article we review recent advances in the delivery of nucleic acids using polymeric and inorganic vectors. We discuss the wide range of materials being designed and evaluated for these purposes while considering the physical requirements and barriers to entry that these agents face and reviewing recent novel approaches towards improving delivery with respect to each of these barriers. Furthermore, we provide a brief overview of past and ongoing nonviral gene therapy clinical trials. We conclude with a discussion of multifunctional nucleic acid carriers and future directions. PMID:22826857

  3. Influence of carbons on the structure of the negative active material of lead-acid batteries and on battery performance

    NASA Astrophysics Data System (ADS)

    Pavlov, D.; Nikolov, P.; Rogachev, T.

    It has been established that addition of carbon additives to the lead negative active material (NAM) of lead-acid batteries increase battery charge acceptance in hybrid electric vehicle mode of operation. The present work studies three types of activated carbons and two types of carbon blacks with the aim to evaluate their efficiency in improving the charge acceptance of lead-acid batteries. It has been established that the size of carbon particles and their affinity to lead are essential. If carbon particles are of nanosizes, they are incorporated into the bulk of the skeleton branches of NAM and may thus increase the latter's ohmic resistance. Their content in NAM should not exceed 0.2-0.5 wt.%. At this loading level, carbon grains are adsorbed only on the surface of NAM contributing to the increase of its specific surface area and thus improving its charge acceptance. When carbon particles are of micron sizes and have high affinity to lead, they are integrated into the skeleton structure of NAM as a structural component and act as super-capacitors, i.e. electric charges are concentrated in them and then the current is distributed along the adjacent branches of the lead skeleton with the lowest ohmic resistance. This eventually improves the charge acceptance of the negative battery plates.

  4. Delta-aminolevulinic acid dehydratase enzyme activity in blood, brain, and liver of lead-dosed ducks

    USGS Publications Warehouse

    Dieter, M.P.; Finley, M.T.

    1979-01-01

    Mallard ducks were dosed with a single shotgun pellet (ca. 200 mg lead). After 1 month there was about 1 ppm lead in blood, 2.5 in liver, and 0.5 in brain. Lead-induced inhibition of delta-aminolevulinic acid dehydratase enzyme in blood and cerebellum was much greater than in cerebral hemisphere or liver and was strongly correlated with the lead concentration in these tissues. The cerebellar portion of the brain was more sensitive to delta-aminolevulinic acid dehydratase enzyme inhibition by lead than were the other tissues examined. There was also a greater increase in the glial cell marker enzyme, butyrylcholinesterase, in cerebellum than in cerebral hemisphere, suggesting that nonregenerating neuronal cells were destroyed by lead and replaced by glial cells in that portion of the brain. Even partial loss of cerebellar tissue is severely debilitating in waterfowl, because functions critical to survival such as visual, auditory, motor, and reflex responses are integrated at this brain center.

  5. Endoplasmic Reticulum Thiol Oxidase Deficiency Leads to Ascorbic Acid Depletion and Noncanonical Scurvy in Mice

    PubMed Central

    Zito, Ester; Hansen, Henning Gram; Yeo, Giles S.H.; Fujii, Junichi; Ron, David

    2012-01-01

    Summary Endoplasmic reticulum (ER) thiol oxidases initiate a disulfide relay to oxidatively fold secreted proteins. We found that combined loss-of-function mutations in genes encoding the ER thiol oxidases ERO1α, ERO1β, and PRDX4 compromised the extracellular matrix in mice and interfered with the intracellular maturation of procollagen. These severe abnormalities were associated with an unexpectedly modest delay in disulfide bond formation in secreted proteins but a profound, 5-fold lower procollagen 4-hydroxyproline content and enhanced cysteinyl sulfenic acid modification of ER proteins. Tissue ascorbic acid content was lower in mutant mice, and ascorbic acid supplementation improved procollagen maturation and lowered sulfenic acid content in vivo. In vitro, the presence of a sulfenic acid donor accelerated the oxidative inactivation of ascorbate by an H2O2-generating system. Compromised ER disulfide relay thus exposes protein thiols to competing oxidation to sulfenic acid, resulting in depletion of ascorbic acid, impaired procollagen proline 4-hydroxylation, and a noncanonical form of scurvy. PMID:22981861

  6. Endoplasmic reticulum thiol oxidase deficiency leads to ascorbic acid depletion and noncanonical scurvy in mice.

    PubMed

    Zito, Ester; Hansen, Henning Gram; Yeo, Giles S H; Fujii, Junichi; Ron, David

    2012-10-12

    Endoplasmic reticulum (ER) thiol oxidases initiate a disulfide relay to oxidatively fold secreted proteins. We found that combined loss-of-function mutations in genes encoding the ER thiol oxidases ERO1α, ERO1β, and PRDX4 compromised the extracellular matrix in mice and interfered with the intracellular maturation of procollagen. These severe abnormalities were associated with an unexpectedly modest delay in disulfide bond formation in secreted proteins but a profound, 5-fold lower procollagen 4-hydroxyproline content and enhanced cysteinyl sulfenic acid modification of ER proteins. Tissue ascorbic acid content was lower in mutant mice, and ascorbic acid supplementation improved procollagen maturation and lowered sulfenic acid content in vivo. In vitro, the presence of a sulfenic acid donor accelerated the oxidative inactivation of ascorbate by an H(2)O(2)-generating system. Compromised ER disulfide relay thus exposes protein thiols to competing oxidation to sulfenic acid, resulting in depletion of ascorbic acid, impaired procollagen proline 4-hydroxylation, and a noncanonical form of scurvy.

  7. Effect of chelation treatment with dimercaptosuccinic acid (DMSA) on lead-related blood pressure changes

    SciTech Connect

    Khalil-Manesh, F.; Gonick, H.C.; Weiler, E.W.J. Univ. of California, Los Angeles ); Prins, B.; Purdy, R. ); Weber, M.A. Univ. of California, Irvine ); Ren, Qing )

    1994-04-01

    An elevation in mean blood pressure was found in rats treated with low lead (0.01%) for 6 months and then only water for an additional 6 months (discontinuous low lead). Not change in blood pressure was found in rats similarly treated with high lead (0.5%) (discontinuous high lead). Administration of DMSA (0.5% in drinking water), for 5 days every 2 months following cessation of lead administration, resulted in a significant lowering of blood pressure in both groups of animals. In the low-lead but not the high-lead group, this was associated with an increase in plasma cyclic GMP (acting as a second messenger for endothelium-derived relaxing factor, EDRF) and a decrease in the plasma concentration of 12-kDa hypertension-associated protein. Plasma endothelin-3 (ET-3) levels were decreased in discontinuous high-lead rats, increased in dicontinuous low-lead rats, but were unaltered by DMSA treatment. We infer that the elevated blood pressure in the discontinuous low-lead rats is related to an increase in the putative vasoconstrictors, ET-3 and the hypertension-associated protein, without a change in the vasodilator, EDRF. With DMSA treatment, plasma cyclic GMP in low-lead rats increased above normal, and the hypertension-associated protein decreased, resulting in lowered blood pressure. DMSA was shown to act as an antioxidant in vitro. Thus the DMSA effect on plasma cGMP (EDRF) may occur via a scavenging effect on EDRF-inactivating reactive oxygen species. 34 refs., 7 figs., 4 tabs.

  8. Effects of curcumin and tannic acid on the aluminum- and lead-induced oxidative neurotoxicity and alterations in NMDA receptors.

    PubMed

    Tüzmen, Münire Nalan; Yücel, Nilgün Candan; Kalburcu, Tülden; Demiryas, Nazan

    2015-02-01

    Exposure to aluminum (Al) and lead (Pb) can cause brain damage. Also, Pb and Al exposure alters N-methyl-d-aspartate receptor (NMDAR) subunit expression. Polyphenols such as tannic acid and curcumin are very efficient chelator for metals. The effects of curcumin and tannic acid (polyphenols) on Al(3+)- and Pb(2+)-induced oxidative stress were examined by investigating lipid peroxidation (LPO) levels, antioxidant enzyme activities, acetyl cholinesterase (AChE) activity and also NMDA receptor subunits 2A and 2B concentrations in the brain tissue of rats sub-chronically. Rats were divided into seven groups as control, Al, Pb, aluminum-tannic acid treatment (AlT), aluminum-curcumin treatment (AlC), lead-tannic acid treatment (PbT) and lead-curcumin treatment (PbC). After 16 weeks of treatment, LPO levels in the brain and hippocampus were higher in Al(3+)-exposed rats than that of Pb(2+)-exposed group. Superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in brain tissue of Al- and Pb-exposed rats increased significantly compared with control, while catalase (CAT) and AChE activities decreased. It was observed that metal exposure affected NR2A concentrations more than NR2B concentrations and also that polyphenol treatments increased these receptor protein concentrations.

  9. Field Turbidity Methods for the Determination of Lead in Acid Extracts of Dried Paint

    EPA Science Inventory

    Lead, which can be found in old paint, soil, and dust, has been clearly shown to have adverse health effects on the neurological systems of both children and adults. As part of an ongoing effort to reduce childhood lead poisoning, the U.S. Environmental Protection Agency promulga...

  10. Co-remediation of the lead-polluted garden soil by exogenous natural zeolite and humic acids.

    PubMed

    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 (p<0.01) reduction in the lead 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 (p<0.01) the water-soluble fraction of lead 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.

  11. Gastric acid reduction leads to an alteration in lower intestinal microflora

    SciTech Connect

    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

    2009-04-17

    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.

  12. Advanced Technologies for Robotic Exploration Leading to Human Exploration: Results from the SpaceOps 2015 Workshop

    NASA Technical Reports Server (NTRS)

    Lupisella, Mark L.; Mueller, Thomas

    2016-01-01

    This paper will provide a summary and analysis of the SpaceOps 2015 Workshop all-day session on "Advanced Technologies for Robotic Exploration, Leading to Human Exploration", held at Fucino Space Center, Italy on June 12th, 2015. The session was primarily intended to explore how robotic missions and robotics technologies more generally can help lead to human exploration missions. The session included a wide range of presentations that were roughly grouped into (1) broader background, conceptual, and high-level operations concepts presentations such as the International Space Exploration Coordination Group Roadmap, followed by (2) more detailed narrower presentations such as rover autonomy and communications. The broader presentations helped to provide context and specific technical hooks, and helped lay a foundation for the narrower presentations on more specific challenges and technologies, as well as for the discussion that followed. The discussion that followed the presentations touched on key questions, themes, actions and potential international collaboration opportunities. Some of the themes that were touched on were (1) multi-agent systems, (2) decentralized command and control, (3) autonomy, (4) low-latency teleoperations, (5) science operations, (6) communications, (7) technology pull vs. technology push, and (8) the roles and challenges of operations in early human architecture and mission concept formulation. A number of potential action items resulted from the workshop session, including: (1) using CCSDS as a further collaboration mechanism for human mission operations, (2) making further contact with subject matter experts, (3) initiating informal collaborative efforts to allow for rapid and efficient implementation, and (4) exploring how SpaceOps can support collaboration and information exchange with human exploration efforts. This paper will summarize the session and provide an overview of the above subjects as they emerged from the SpaceOps 2015

  13. Pyrolysis of simple coal model compounds containing aromatic carboxylic acids: Does decarboxylation lead to cross-linking?

    SciTech Connect

    Eskay, T.P.; Britt, P.F.; Buchanan, A.C. III

    1996-02-01

    The thermolysis of two aromatic carboxylic acids 1,2-(3,3`-dicarboxyphenyl)ethane (2) have been investigated at 400{degree} C as models of carboxylic acids in low rank coals. The major decomposition pathway observed is decarboxylation, which mainly occurs by an ionic pathway. This decarboxylation route does not lead to any significant amount of coupling or high molecular weight products that would be indicative of cross-linking products in coal. The pyrolysis of 1 and 2 will be investigated under a variety of conditions that better mimic the enviromment found in coal to further delineate the role that decarboxylation plays in coal cross-linking chemistry.

  14. A Multi-Point Sensor Based on Optical Fiber for the Measurement of Electrolyte Density in Lead-Acid Batteries

    PubMed Central

    Cao-Paz, Ana M.; Marcos-Acevedo, Jorge; del Río-Vázquez, Alfredo; Martínez-Peñalver, Carlos; Lago-Ferreiro, Alfonso; Nogueiras-Meléndez, Andrés A.; Doval-Gandoy, Jesús

    2010-01-01

    This article describes a multi-point optical fiber-based sensor for the measurement of electrolyte density in lead-acid batteries. It is known that the battery charging process creates stratification, due to the different densities of sulphuric acid and water. In order to study this process, density measurements should be obtained at different depths. The sensor we describe in this paper, unlike traditional sensors, consists of several measurement points, allowing density measurements at different depths inside the battery. The obtained set of measurements helps in determining the charge (SoC) and state of health (SoH) of the battery. PMID:22319262

  15. Recent advances in delivery of drug-nucleic acid combinations for cancer treatment.

    PubMed

    Li, Jing; Wang, Yan; Zhu, Yu; Oupický, David

    2013-12-10

    Cancer treatment that uses a combination of approaches with the ability to affect multiple disease pathways has been proven highly effective in the treatment of many cancers. Combination therapy can include multiple chemotherapeutics or combinations of chemotherapeutics with other treatment modalities like surgery or radiation. However, despite the widespread clinical use of combination therapies, relatively little attention has been given to the potential of modern nanocarrier delivery methods, like liposomes, micelles, and nanoparticles, to enhance the efficacy of combination treatments. This lack of knowledge is particularly notable in the limited success of vectors for the delivery of combinations of nucleic acids with traditional small molecule drugs. The delivery of drug-nucleic acid combinations is particularly challenging due to differences in the physicochemical properties of the two types of agents. This review discusses recent advances in the development of delivery methods using combinations of small molecule drugs and nucleic acid therapeutics to treat cancer. This review primarily focuses on the rationale used for selecting appropriate drug-nucleic acid combinations as well as progress in the development of nanocarriers suitable for simultaneous delivery of drug-nucleic acid combinations.

  16. Maternal fructose drives placental uric acid production leading to adverse fetal outcomes

    PubMed Central

    Asghar, Zeenat A.; Thompson, Alysha; Chi, Maggie; Cusumano, Andrew; Scheaffer, Suzanne; Al-Hammadi, Noor; Saben, Jessica L.; Moley, Kelle H.

    2016-01-01

    Maternal metabolic diseases increase offspring risk for low birth weight and cardiometabolic diseases in adulthood. Excess fructose consumption may confer metabolic risks for both women and their offspring. However, the direct consequences of fructose intake per se are unknown. We assessed the impact of a maternal high-fructose diet on the fetal-placental unit in mice in the absence of metabolic syndrome and determined the association between maternal serum fructose and placental uric acid levels in humans. In mice, maternal fructose consumption led to placental inefficiency, fetal growth restriction, elevated fetal serum glucose and triglyceride levels. In the placenta, fructose induced de novo uric acid synthesis by activating the activities of the enzymes AMP deaminase and xanthine oxidase. Moreover, the placentas had increased lipids and altered expression of genes that control oxidative stress. Treatment of mothers with the xanthine oxidase inhibitor allopurinol reduced placental uric acid levels, prevented placental inefficiency, and improved fetal weights and serum triglycerides. Finally, in 18 women delivering at term, maternal serum fructose levels significantly correlated with placental uric acid levels. These findings suggest that in mice, excess maternal fructose consumption impairs placental function via a xanthine oxidase/uric acid-dependent mechanism, and similar effects may occur in humans. PMID:27125896

  17. Maternal fructose drives placental uric acid production leading to adverse fetal outcomes.

    PubMed

    Asghar, Zeenat A; Thompson, Alysha; Chi, Maggie; Cusumano, Andrew; Scheaffer, Suzanne; Al-Hammadi, Noor; Saben, Jessica L; Moley, Kelle H

    2016-04-29

    Maternal metabolic diseases increase offspring risk for low birth weight and cardiometabolic diseases in adulthood. Excess fructose consumption may confer metabolic risks for both women and their offspring. However, the direct consequences of fructose intake per se are unknown. We assessed the impact of a maternal high-fructose diet on the fetal-placental unit in mice in the absence of metabolic syndrome and determined the association between maternal serum fructose and placental uric acid levels in humans. In mice, maternal fructose consumption led to placental inefficiency, fetal growth restriction, elevated fetal serum glucose and triglyceride levels. In the placenta, fructose induced de novo uric acid synthesis by activating the activities of the enzymes AMP deaminase and xanthine oxidase. Moreover, the placentas had increased lipids and altered expression of genes that control oxidative stress. Treatment of mothers with the xanthine oxidase inhibitor allopurinol reduced placental uric acid levels, prevented placental inefficiency, and improved fetal weights and serum triglycerides. Finally, in 18 women delivering at term, maternal serum fructose levels significantly correlated with placental uric acid levels. These findings suggest that in mice, excess maternal fructose consumption impairs placental function via a xanthine oxidase/uric acid-dependent mechanism, and similar effects may occur in humans.

  18. Role of ascorbic acid in scavenging free radicals and lead toxicity from biosystems.

    PubMed

    Tariq, Shabbir A

    2007-09-01

    Free radicals are reactive species that are responsible for damaging normal cells and creating diseases in humans. Antioxidants from natural resources or as supplements can scavenge these radicals. A MedLine search indicates that vitamin C is the most investigated antioxidant responsible for the elimination of free radicals. Its chelating property for the removal of neurotoxic lead, which creates oxidative stress in the human biosystem, was investigated and results indicate its great potential as a lead-detoxifying agent.

  19. Activation of the Glutamic Acid-Dependent Acid Resistance System in Escherichia coli BL21(DE3) Leads to Increase of the Fatty Acid Biotransformation Activity

    PubMed Central

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

    2016-01-01

    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. PMID:27681369

  20. Activation of the Glutamic Acid-Dependent Acid Resistance System in Escherichia coli BL21(DE3) Leads to Increase of the Fatty Acid Biotransformation Activity.

    PubMed

    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.

  1. Comprehensive Analysis of 5-Aminolevulinic Acid Dehydrogenase (ALAD) Variants and Renal Cell Carcinoma Risk among Individuals Exposed to Lead

    PubMed Central

    van Bemmel, Dana M.; Boffetta, Paolo; Liao, Linda M.; Berndt, Sonja I.; Menashe, Idan; Yeager, Meredith; Chanock, Stephen; Karami, Sara; Zaridze, David; Matteev, Vsevolod; Janout, Vladimir; Kollarova, Hellena; Bencko, Vladimir; Navratilova, Marie; Szeszenia-Dabrowska, Neonilia; Mates, Dana; Slamova, Alena; Rothman, Nathaniel; Han, Summer S.; Rosenberg, Philip S.; Brennan, Paul; Chow, Wong-Ho; Moore, Lee E.

    2011-01-01

    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 rs8177796CT/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 (pint = 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. PMID:21799727

  2. Premature capacity loss in lead/acid batteries: a discussion of the antimony-free effect and related phenomena

    NASA Astrophysics Data System (ADS)

    Hollenkamp, A. F.

    Instances of severe capacity loss in apparently healthy lead/acid batteries have been reported over a period of many years, and are still common today. In most cases, these phenomena are linked to the use of antimony-free positive grids and are invoked by repetitive deep-discharge duties. This situation represents probably the greatest barrier to the expansion of markets for lead/acid batteries. To date, research has focused on several possible explanations for capacity loss; notably, degradation of the positive active mass (e.g., relaxable insufficient mass utilization) and the development of electrical barriers around the grid. Although much of the evidence gathered is circumstantial, it does point to the key issues that must be addressed in future work.

  3. Trends for isolated amino acids and dipeptides: Conformation, divalent ion binding, and remarkable similarity of binding to calcium and lead

    NASA Astrophysics Data System (ADS)

    Ropo, M.; Blum, V.; Baldauf, C.

    2016-11-01

    We derive structural and binding energy trends for twenty amino acids, their dipeptides, and their interactions with the divalent cations Ca2+, Ba2+, Sr2+, Cd2+, Pb2+, and Hg2+. The underlying data set consists of more than 45,000 first-principles predicted conformers with relative energies up to ~4 eV (~400 kJ/mol). We show that only very few distinct backbone structures of isolated amino acids and their dipeptides emerge as lowest-energy conformers. The isolated amino acids predominantly adopt structures that involve an acidic proton shared between the carboxy and amino function. Dipeptides adopt one of two intramolecular-hydrogen bonded conformations C5 or . Upon complexation with a divalent cation, the accessible conformational space shrinks and intramolecular hydrogen bonding is prevented due to strong electrostatic interaction of backbone and side chain functional groups with cations. Clear correlations emerge from the binding energies of the six divalent ions with amino acids and dipeptides. Cd2+ and Hg2+ show the largest binding energies–a potential correlation with their known high acute toxicities. Ca2+ and Pb2+ reveal almost identical binding energies across the entire series of amino acids and dipeptides. This observation validates past indications that ion-mimicry of calcium and lead should play an important role in a toxicological context.

  4. Trends for isolated amino acids and dipeptides: Conformation, divalent ion binding, and remarkable similarity of binding to calcium and lead

    PubMed Central

    Ropo, M.; Blum, V.; Baldauf, C.

    2016-01-01

    We derive structural and binding energy trends for twenty amino acids, their dipeptides, and their interactions with the divalent cations Ca2+, Ba2+, Sr2+, Cd2+, Pb2+, and Hg2+. The underlying data set consists of more than 45,000 first-principles predicted conformers with relative energies up to ~4 eV (~400 kJ/mol). We show that only very few distinct backbone structures of isolated amino acids and their dipeptides emerge as lowest-energy conformers. The isolated amino acids predominantly adopt structures that involve an acidic proton shared between the carboxy and amino function. Dipeptides adopt one of two intramolecular-hydrogen bonded conformations C5 or . Upon complexation with a divalent cation, the accessible conformational space shrinks and intramolecular hydrogen bonding is prevented due to strong electrostatic interaction of backbone and side chain functional groups with cations. Clear correlations emerge from the binding energies of the six divalent ions with amino acids and dipeptides. Cd2+ and Hg2+ show the largest binding energies–a potential correlation with their known high acute toxicities. Ca2+ and Pb2+ reveal almost identical binding energies across the entire series of amino acids and dipeptides. This observation validates past indications that ion-mimicry of calcium and lead should play an important role in a toxicological context. PMID:27808109

  5. The clouds of Venus - Sulfuric acid by the lead chamber process

    NASA Technical Reports Server (NTRS)

    Sill, G. T.

    1983-01-01

    The Pioneer Venus atmospheric probe provided new data on the clouds of Venus. A model consistent with this data involves SO2 being oxidized to H2SO4 by NO(x) in the presence of H2O. NO(x) also forms nitrosylsulfuric acid (NOHSO4) dissolved in the H2SO4 droplets. This acid solution, along with SO2 and perhaps NO2, can explain the UV and visible reflection spectrum of Venus. In the middle and lower clouds, NOHSO4 forms solid particles.

  6. Therapeutic potentials of combined use of DMSA with calcium and ascorbic acid in the treatment of mild to moderately lead intoxicated mice.

    PubMed

    Liao, Yingjun; Zhang, Jun; Jin, Yaping; Lu, Chunwei; Li, Gexin; Yu, Fei; Zhi, Xuping; An, Li; Yang, Jun

    2008-02-01

    The aim of this study was to explore the therapeutic efficacies of combined use of meso-2,3-dimercaptosuccinic acid (DMSA) with calcium and ascorbic acid in the treatment of mild to moderately lead-intoxicated mice. Female albino mice were exposed to lead by drinking water contaminated with 0.1% (moderate lead exposure) or 0.05% (mild lead exposure) lead acetate. After the cessation of lead exposure, mice were supplemented by gavage with saline solution, 50 mg/kg body weight (b.w) DMSA, 100 mg/kg b.w DMSA, calcium and ascorbic acid, or 50 mg/kg b.w DMSA and calcium as well as ascorbic acid, respectively. Atomic absorption spectrophotometric method was used to analyze lead levels in blood, bone, liver, kidney and brain. Activities of blood delta-aminolevulinic acid dehydratase (ALAD) were determined by colorimetric method. DMSA supplemented alone could reduce lead levels in both soft tissues and bone and reverse lead-inhibited activities of blood ALAD in mild to moderately lead-intoxicated mice. On the other hand, combined use of DMSA with calcium and ascorbic acid achieved better therapeutic efficacies in mobilizing lead in blood, liver and kidney, and reversing lead-inhibited activities of blood ALAD in moderately lead intoxicated mice than DMSA supplemented alone. Moreover, the better therapeutic efficacies were also found in mildly lead intoxicated mice in mobilizing lead in blood and bone achieved by combined use of DMSA with calcium and ascorbic acid. Combined use of DMSA with calcium and ascorbic acid seems to be the better choice in the treatment of mild to moderate lead-intoxication.

  7. Modified titanium foil's surface by high temperature carbon sintering method as the substrate for bipolar lead-acid battery

    NASA Astrophysics Data System (ADS)

    Lang, Xiaoshi; Wang, Dianlong; Zhu, Junsheng

    2014-12-01

    Titanium foil can be a type of ideal material as the substrate for bipolar lead-acid battery. However, it can't be directly used because it can be oxidized in the high voltage and strong oxidizing conditions. In this paper, we coat the titanium suboxide on the titanium foil surface by means of the high temperature carbon sintering method for the improvement of corrosion resistance of titanium metal and use it as the substrate to bipolar lead-acid battery to study its effect on the battery performances. Modified titanium foils are characterized by SEM, XRD, corrosion resistance test and electronic conductivity test. The electrochemical properties of the bipolar lead-acid battery are investigated by constant current charge/discharge method. The results demonstrate that the titanium foil carbon-sintered at 800 °C for 2 h has the most excellent chemical stability and electronic conductivity. Initial specific capacities of positive active material of bipolar lead-acid battery with modified titanium as the substrate at 0.25C, 0.5C, 1C and 2C discharge rate are 99.29 mAh g-1, 88.93 mAh g-1, 77.54 mAh g-1, and 65.41 mAh g-1. After 50 cycles, the specific capacity of positive active material at 0.5C is 81.36 mAh g-1 and after 100 cycles, the specific capacity at 1C is 61.92 mAh g-1.

  8. Comparative study of cadmium and lead accumulations in Cambarus bartoni (Fab. ) (Decapoda, Crustacea) from an acidic and a neutral lake

    SciTech Connect

    Keenan, S.; Alikhan, M.A. )

    1991-07-01

    The purpose of the study reported in this paper was to compare concentrations of lead and cadmium in the sediment and water, as well as in the crayfish, Cambarus Bartoni (Fab.) (Decapoda - Crustacea) trapped from an acidic and a neutral lake in the Sudbury district of Northeastern Ontario. Hepatopancreatic, alimentary canal, tail muscles and exoskeletal concentrations in the crayfish are also examined to determine specific tissue sites for these accumulations.

  9. Design of acid-lead battery stage-of-charge detection system based on refractive index detection technology

    NASA Astrophysics Data System (ADS)

    Chen, Junyao; Yang, Kecheng; Xia, Min; Li, Lei; Zeng, Xianjiang

    2015-10-01

    Based on optical total reflection critical Angle method, we have designed a refractive index measurement system. It adopted a divergent light source and a CCD camera as the occurrence and receiver of the signal. The divergent light source sent out a bunch of tapered beam, exposure to the interface of optical medium and sulfuric acid solution. Light intensity reflected from the interface could be detected by the CCD camera and then sent to the embedded system. In the DSP embedded system, we could obtain the critical edge position through the light intensity distribution curve and converted it to critical angle. Through experiment, we concluded the relation between liquid refractive index and the critical angle edge position. In this system, the detecting precision of the refractive index of sulfuric acid solution reached 10-4. Finally, through the conversion of the refractive index and density, we achieved high accuracy online measurement of electrolyte density in lead-acid battery.

  10. The lead-acid battery industry in China: outlook for production and recycling.

    PubMed

    Tian, Xi; Wu, Yufeng; Gong, Yu; Zuo, Tieyong

    2015-11-01

    In 2013, more than four million (metric) tons (MT) of refined lead went into batteries in China, and 1.5 MT of scrap lead recycled from these batteries was reused in other secondary materials. The use of start-light-ignition (SLI), traction and energy storage batteries has spread in China in recent decades, with their proportions being 25.6%, 47.2% and 27.2%, respectively, in 2012. The total production of these batteries increased from 296,000 kVAh in 2001 to 205.23 MkVAh in 2013, with manufacturing located mainly in the middle and eastern provinces of the country. In this paper, we find that the market share of SLI batteries will decrease slightly, the share of traction batteries will continuously increase with the emergence of clean energy vehicles, and that of energy storage batteries will increase with the development of the wind energy and photovoltaic industries. Accounting for lead consumption in the main application industries, and the total social possession, it is calculated that used lead batteries could generate 2.4 MT of scrap lead in 2014, which is much higher than the 1.5 MT that was recycled in 2013. Thus, the current recycling rate is too low. It is suggested that while building large-scale recycling plants, small-scale plants should be banned or merged.

  11. Identification of the phytosphingosine metabolic pathway leading to odd-numbered fatty acids.

    PubMed

    Kondo, Natsuki; Ohno, Yusuke; Yamagata, Maki; Obara, Takashi; Seki, Naoya; Kitamura, Takuya; Naganuma, Tatsuro; Kihara, Akio

    2014-10-27

    The long-chain base phytosphingosine is a component of sphingolipids and exists in yeast, plants and some mammalian tissues. Phytosphingosine is unique in that it possesses an additional hydroxyl group compared with other long-chain bases. However, its metabolism is unknown. Here we show that phytosphingosine is metabolized to odd-numbered fatty acids and is incorporated into glycerophospholipids both in yeast and mammalian cells. Disruption of the yeast gene encoding long-chain base 1-phosphate lyase, which catalyzes the committed step in the metabolism of phytosphingosine to glycerophospholipids, causes an ~40% reduction in the level of phosphatidylcholines that contain a C15 fatty acid. We also find that 2-hydroxypalmitic acid is an intermediate of the phytosphingosine metabolic pathway. Furthermore, we show that the yeast MPO1 gene, whose product belongs to a large, conserved protein family of unknown function, is involved in phytosphingosine metabolism. Our findings provide insights into fatty acid diversity and identify a pathway by which hydroxyl group-containing lipids are metabolized.

  12. Lead detoxification activities of a class of novel DMSA--amino acid conjugates.

    PubMed

    Xu, Yanxia; Wang, Yuji; Wang, Ling; Zhao, Ming; Zhang, Xiaoyi; Hu, Xiaomin; Hou, Baoguang; Peng, Li; Zheng, Meiqing; Wu, Jianhui; Peng, Shiqi

    2011-06-20

    The coupling of the 1-carboxyl of DMSA with l-amino acids led to a class of novel 1-(carbonyl-l-amino-acid)-2,3-dimercaptosuccinic acids (DMSA--amino acid conjugates, DMSA-Gly, -Ser, -Val, -Leu, -Ile, -Asn, -Asp, -Gln, -Glu, -Met, -Phe, and -Trp). In the in vivo evaluation of Pb-loaded mice, 0.4 mmol/kg of the conjugates effectively decreased the Pb levels of the femur, brain, kidney, liver, and blood, greatly enhanced urination, and increased the Pb levels of both urine and feces, while causing no redistributions of Pb to the other organs, especially to the brain. With respect to lowering the bone and brain Pb, DMSA-Ile, -Asn, -Gln, and -Met were more effective than DMSA. This benefit was attributed to their high transmembrane ability. In contrast to Pb, the essential metals such as Fe, Cu, Zn, and Ca of the treated mice were not affected by the administration of the conjugates. Silico molecular modeling predicted that the conjugates had little hepatotoxicity, except possibly for DMSA-Phe.

  13. Immobilization of lead in anthropogenic contaminated soils using phosphates with/without oxalic acid.

    PubMed

    Su, Xiaojuan; Zhu, Jun; Fu, Qingling; Zuo, Jichao; Liu, Yonghong; Hu, Hongqing

    2015-02-01

    Understanding the effects of oxalic acid (OA) on the immobilization of Pb(II) in contaminated soils by phosphate materials, has considerable benefits for risk assessment and remediation strategies for the soil. A series of phosphate amendments with/without oxalic acid were applied to two anthropogenic contaminated soils. We investigated the immobilization of Pb(II) by KH2PO4, phosphate rock (PR), activated phosphate rock (APR) and synthetic hydroxyapatite (HAP) at different phosphate:Pb (P:Pb) molar ratios (0, 0.6, 2.0 and 4.0) in the presence/absence of 50 mmol oxalic acid/kg soil, respectively. The effects of treatments were evaluated using single extraction with deionized water or CaCl2, Community Bureau of Reference (BCR) sequential extraction and toxicity characteristic leaching procedure (TCLP) methods. Our results showed that the concentration of water extractable, exchangeable and TCLP-Pb all decreased with incubation time. The concentration of water-extractable Pb after 120 days was reduced by 100% when soils were amended with APR, HAP and HAP+OA, and the TCLP-Pb was <5 mg/L for the red soil at P:Pb molar ratio 4.0. Water-soluble Pb could not be detected and the TCLP-Pb was <5 mg/L at all treatments applied to the yellow-brown soil. BCR results indicated that APR was most effective, although a slight enhancement of water-soluble phosphate was detected at the P:Pb molar ratio 4.0 at the beginning of incubation. Oxalic acid activated phosphates, and so mixing insoluble phosphates with oxalic acid may be a useful strategy to improve their effectiveness in reducing Pb bioavailability.

  14. Tolfenamic acid downregulates BACE1 and protects against lead-induced upregulation of Alzheimer's disease related biomarkers.

    PubMed

    Adwan, Lina; Subaiea, Gehad M; Zawia, Nasser H

    2014-04-01

    Environmental exposure to lead (Pb) early in life results in a latent upregulation of genes and products associated with Alzheimer's disease (AD), particularly the plaque forming protein amyloid beta (Aβ). Furthermore, animals exposed to Pb as infants develop cognitive decline and memory impairments in old age. Studies from our lab demonstrated that tolfenamic acid lowers the levels of the amyloid β precursor protein (APP) and its aggregative cleavage product Aβ by inducing the degradation of the transcription factor specificity protein 1 (Sp1). These changes were accompanied by cognitive improvement in transgenic APP knock-in mice. In this study, we examined the effects of tolfenamic acid on beta site APP cleaving enzyme 1 (BACE1) which is responsible for Aβ production and tested its ability to reverse Pb-induced upregulation in the amyloidogenic pathway. Mice were administered tolfenamic acid for one month and BACE1 gene expression as well as its enzymatic activity were analyzed in the cerebral cortex. Tolfenamic acid was also tested for its ability to reverse changes in Sp1, APP and Aβ that were upregulated by Pb in vitro. Differentiated SH-SY5Y neuroblastoma cells were either left unexposed, or sequentially exposed to Pb followed by tolfenamic acid. Our results show that tolfenamic acid reduced BACE1 gene expression and enzyme activity in mice. In neuroblastoma cells, Pb upregulated Sp1, APP and Aβ, while tolfenamic acid lowered their expression. These results along with previous data from our lab provide evidence that tolfenamic acid, a drug that has been used for decades for migraine, represents a candidate which can reduce the pathology of AD and may mitigate the damage of environmental risk factors associated with this disease.

  15. Rapid reduction of lead leachate from hazardous fly ash using microwave treatment with acid combination.

    PubMed

    Chou, Chih-Mei; Wang, Li-Pang; Kao, Jimmy C M; Lin, Kae-Long; Chang, Yu-Min

    2016-02-01

    The novelty of this study is to rapidly reduce hazardous lead leachates from solid waste using microwave digestion treatment, which is an energy-saving and low greenhouse gas emission technology. The article presents the reduction of toxic characteristic leaching procedure-extractable lead concentration in the municipal solid waste incineration fly ash by the microwave digestion treatment in HNO3/H2SO4 combination, and focuses on the effects of treatment time and temperature. The results obtained from this study indicated a significant reduction efficiency of toxic characteristic leaching procedure-extractable lead concentration and showed sufficient reduction in leaching levels to render the treated fly ash safe in lead compound leaching characteristics. The reduction efficiency of toxic characteristic leaching procedure-extractable lead concentration can reach 98% in 15 minutes of treatment time. This is equivalent to the original toxic characteristic leaching procedure-extractable lead concentration of 46.2 mg L(-1) in raw fly ash being reduced down to less than 1.0 mg L(-1). Based on the experimental data obtained in this study, a useful correlation between reduction efficiency and treatment conditions is proposed. For engineering applications, the necessary minimum treatment time is solved using a graphic illustration method, by which the minimum treatment time (t(min)) is obtained if the desired reduction efficiency (η) and treatment temperature (T) are known. The effects of treatment time and temperature are discussed. Some problems caused by the microwave digestion treatment method are also delineated in this article.

  16. [Advancement in the research of early detection of bacterial nucleic acid in molecular diagnosis of sepsis].

    PubMed

    Liu, Xiao; Ren, Hui; Peng, Dai-zhi

    2013-04-01

    Early diagnosis of sepsis helps make effective clinical decisions and improve the survival rate of patients with severe infection. However, the timely and accurate diagnosis of sepsis is still a great challenge in clinic. In order to settle the very problem, the scientists in the world have made a lot of exploration and research in the field of rapid molecular identification of pathogens. Nowadays, the nucleic acid detection of sepsis is mainly composed of 3 types of methodological strategies, either based on positive blood culture, single colonies, or directly on blood specimens. This paper presents a comprehensive overview of advances in the research of early detection of bacterial nucleic acid as molecular diagnosis of sepsis.

  17. 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.

    PubMed

    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

  18. Recent Advances in Nucleic Acid-Based Delivery: From Bench to Clinical Trials in Genetic Diseases.

    PubMed

    Oliveira, Cláudia; Ribeiro, António J; Veiga, Francisco; Silveira, Isabel

    2016-05-01

    Delivery of nucleic acids is the most promising therapy for many diseases that remain untreatable. Therefore, many research efforts have been put on finding a safe and efficient delivery system able to provide a sustained response. Viral vectors have proved to be the most efficient for delivery of nucleic acids and, thus, stand as the foremost vector used in current clinical trials. However, safety issues arise as a main concern and mitigate their use, impelling the improvement of non-viral alternatives. This review focuses on the recent advances in pre-clinical development of non-viral polyplexes and lipoplexes for nucleic acid-based delivery, in contrast with vectors being used in present clinical trials. Nucleic acid vectors for neurodegenerative ataxias, Parkinson's disease, retinitis pigmentosa, cystic fibrosis, hemophilia, pancreatic and lung cancer, and rheumatoid arthritis are discussed to illustrate current state of pre-clinical and clinical studies. Thereby, denoting the prospects for treatment of genetic diseases and elucidating the trend in non-viral vector development and improvement which is expected to significantly increase disease rescue exceeding the modest clinical successes observed so far.

  19. Decomposition of two haloacetic acids in water using UV radiation, ozone and advanced oxidation processes.

    PubMed

    Wang, Kunping; Guo, Jinsong; Yang, Min; Junji, Hirotsuji; Deng, Rongsen

    2009-03-15

    The decomposition of two haloacetic acids (HAAs), dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA), from water was studied by means of single oxidants: ozone, UV radiation; and by the advanced oxidation processes (AOPs) constituted by combinations of O(3)/UV radiation, H(2)O(2)/UV radiation, O(3)/H(2)O(2), O(3)/H(2)O(2)/UV radiation. The concentrations of HAAs were analyzed at specified time intervals to elucidate the decomposition of HAAs. Single O(3) or UV did not result in perceptible decomposition of HAAs within the applied reaction time. O(3)/UV showed to be more suitable for the decomposition of DCAA and TCAA in water among the six methods of oxidation. Decomposition of DCAA was easier than TCAA by AOPs. For O(3)/UV in the semi-continuous mode, the effective utilization rate of ozone for HAA decomposition decreased with ozone addition. The kinetics of HAAs decomposition by O(3)/UV and the influence of coexistent humic acids and HCO(3)(-) on the decomposition process were investigated. The decomposition of the HAAs by the O(3)/UV accorded with the pseudo-first-order mode under the constant initial dissolved O(3) concentration and fixed UV radiation. The pseudo-first-order rate constant for the decomposition of DCAA was more than four times that for TCAA. Humic acids can cause the H(2)O(2) accumulation and the decrease in rate constants of HAAs decomposition in the O(3)/UV process. The rate constants for the decomposition of DCAA and TCAA decreased by 41.1% and 23.8%, respectively, when humic acids were added at a concentration of 1.2mgTOC/L. The rate constants decreased by 43.5% and 25.9%, respectively, at an HCO(3)(-) concentration of 1.0mmol/L.

  20. SUNRAYCE 95: Working safely with lead-acid batteries and photovoltaic power systems

    SciTech Connect

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

    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.

  1. SUNRAYCE 1995: Working safely with lead-acid batteries and photovoltaic power systems

    NASA Astrophysics Data System (ADS)

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

    1994-05-01

    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.

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

    PubMed

    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.

  3. Loss of Free Fatty Acid Receptor 2 leads to impaired islet mass and beta cell survival

    PubMed Central

    Villa, Stephanie R.; Priyadarshini, Medha; Fuller, Miles H.; Bhardwaj, Tanya; Brodsky, Michael R.; Angueira, Anthony R.; Mosser, Rockann E.; Carboneau, Bethany A.; Tersey, Sarah A.; Mancebo, Helena; Gilchrist, Annette; Mirmira, Raghavendra G.; Gannon, Maureen; Layden, Brian T.

    2016-01-01

    The regulation of pancreatic β cell mass is a critical factor to help maintain normoglycemia during insulin resistance. Nutrient-sensing G protein-coupled receptors (GPCR) contribute to aspects of β cell function, including regulation of β cell mass. Nutrients such as free fatty acids (FFAs) contribute to precise regulation of β cell mass by signaling through cognate GPCRs, and considerable evidence suggests that circulating FFAs promote β cell expansion by direct and indirect mechanisms. Free Fatty Acid Receptor 2 (FFA2) is a β cell-expressed GPCR that is activated by short chain fatty acids, particularly acetate. Recent studies of FFA2 suggest that it may act as a regulator of β cell function. Here, we set out to explore what role FFA2 may play in regulation of β cell mass. Interestingly, Ffar2−/− mice exhibit diminished β cell mass at birth and throughout adulthood, and increased β cell death at adolescent time points, suggesting a role for FFA2 in establishment and maintenance of β cell mass. Additionally, activation of FFA2 with Gαq/11-biased agonists substantially increased β cell proliferation in in vitro and ex vivo proliferation assays. Collectively, these data suggest that FFA2 may be a novel therapeutic target to stimulate β cell growth and proliferation. PMID:27324831

  4. Testing of Minuteman launch facility flooded lead acid batteries for service life projection

    SciTech Connect

    Oley, F.; Ang, V. |

    1996-11-01

    Capacity performance tests were completed on 47 flooded lead-calcium batteries ranging from 5- to 23-years-old. These batteries had been maintained in the Minuteman missile silos on float charge over the majority of their life to provide emergency or secondary power. Capacity results showed no capacity degradation in the oldest batteries and cell dissections revealed only minor deterioration of the lead calcium grids. However, an increase in the cell float voltage range was observed in the 23-year-old batteries. Although signs of deterioration have begun, the solid capacity results indicate additional service life is still available. Additional data is also presented from on-going cycle tests being performed on a 5- and 21-year-old battery which supports the performance capability remaining in these aged batteries.

  5. Rhabdomyolysis-Associated Mutations in Human LPIN1 Lead to Loss of Phosphatidic Acid Phosphohydrolase Activity.

    PubMed

    Schweitzer, George G; Collier, Sara L; Chen, Zhouji; Eaton, James M; Connolly, Anne M; Bucelli, Robert C; Pestronk, Alan; Harris, Thurl E; Finck, Brian N

    2015-01-01

    Rhabdomyolysis is an acute syndrome due to extensive injury of skeletal muscle. Recurrent rhabdomyolysis is often caused by inborn errors in intermediary metabolism, and recent work has suggested that mutations in the human gene encoding lipin 1 (LPIN1) may be a common cause of recurrent rhabdomyolysis in children. Lipin 1 dephosphorylates phosphatidic acid to form diacylglycerol (phosphatidic acid phosphohydrolase; PAP) and acts as a transcriptional regulatory protein to control metabolic gene expression. Herein, a 3-year-old boy with severe recurrent rhabdomyolysis was determined to be a compound heterozygote for a novel c.1904T>C (p.Leu635Pro) substitution and a previously reported genomic deletion of exons 18-19 (E766-S838_del) in LPIN1. Western blotting with patient muscle biopsy lysates demonstrated a marked reduction in lipin 1 protein, while immunohistochemical staining for lipin 1 showed abnormal subcellular localization. We cloned cDNAs to express recombinant lipin 1 proteins harboring pathogenic mutations and showed that the E766-S838_del allele was not expressed at the RNA or protein level. Lipin 1 p.Leu635Pro was expressed, but the protein was less stable, was aggregated in the cytosol, and was targeted for proteosomal degradation. Another pathogenic single amino acid substitution, lipin 1 p.Arg725His, was well expressed and retained its transcriptional regulatory function. However, both p.Leu635Pro and p.Arg725His proteins were found to be deficient in PAP activity. Kinetic analyses demonstrated a loss of catalysis rather than diminished substrate binding. These data suggest that loss of lipin 1-mediated PAP activity may be involved in the pathogenesis of rhabdomyolysis in lipin 1 deficiency.

  6. Enteric coating can lead to reduced antiplatelet effect of low-dose acetylsalicylic acid.

    PubMed

    Haastrup, Peter Fentz; Grønlykke, Thor; Jarbøl, Dorte Ejg

    2015-03-01

    Low-dose acetylsalicylic acid (ASA) is widely used as antithrombotic prophylaxis. Enteric-coated ASA has been developed to decrease the risk of gastrointestinal side effects. The consequences of enteric coating on pharmacokinetics and antiplatelet effect of ASA have not systematically been assessed. This MiniReview demonstrates that data from clinical trials indicate that enteric coating can reduce the antiplatelet effect of ASA compared to plain ASA. This is possibly due to decreased bioavailability of ASA caused by prolonged solvation and absorption of the enteric-coated formulations. Therefore, low-dose enteric-coated ASA might not be bioequivalent to plain ASA, entailing the risk of insufficient cardiovascular prophylaxis.

  7. Tegafur-uracil (UFT) plus folinic acid in advanced rectal cancer.

    PubMed

    Sanchiz, F; Milla, A

    1994-12-01

    We previously reported positive results to Tegafur-Uracil (UFT) chemotherapy in a group of patients with advanced rectal cancer. We have continued the study and now report the effectiveness of UFT plus folinic acid (FA) in 52 patients with advanced rectal cancer. The therapeutic schedule was UFT, 600 mg/m2/day x 14 days p.o. + FA, 90 mg/m2/day x 14 days p.o. Fifty-two out of a total of 56 patients were evaluated for response and toxicity. A higher incidence of positive responses in patients without previous chemotherapy was appreciated. Twenty-one of the 52 evaluated patients showed a partial response (PR). Responses were strongly correlated with previous chemotherapy (14/20; 70% PR of cases without previous chemotherapy vs 7/32; 22% of cases with previous chemotherapy). All responding patients came forward with a median time to progression of 8.2 months (19.6 months for patients without previous chemotherapy vs 7.7 months for patients with previous chemotherapy, P < 0.01). We concluded that the UFT plus FA could be a treatment of choice for patients with advanced rectal cancer.

  8. Apparent Consumption vs. Total Consumption--A Lead-Acid Battery Case Study

    USGS Publications Warehouse

    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

  9. Research, development, and demonstration of lead-acid batteries for electric vehicle propulsion. Annual report, 1979

    SciTech Connect

    Not Available

    1980-06-01

    The initial phase of work comprises three factorial experiments to evaluate a variety of component combinations. Goals to be met by these batteries include the following: capacity at 3 h discharge, 20 to 30 kWh; specific energy, 40 Wh/kg; specific power, 1000 W/kg for 15 s; cycle life, 800 cycles to 80% depth; price, $50/kWh. The status of the factorial experiments is reviewed. The second phase of work, design of an advanced battery, has the following goals: 30 to 40 kWh; 60 Wh/kg; 150 W/kg for 15 s; 1000 cycles to 80% depth; $40/kWh. It is not yet possible to say whether these goals can be met. Numerous approaches are under study to increase the utilization of battery chemicals. A battery design with no live electrical connection above the battery is being developed. 52 figures, 52 tables. (RWR)

  10. Reductive smelting of spent lead-acid battery colloid sludge in a molten Na2CO3 salt

    NASA Astrophysics Data System (ADS)

    Hu, Yu-jie; Tang, Chao-bo; Tang, Mo-tang; Chen, Yong-ming

    2015-08-01

    Lead extraction from spent lead-acid battery paste in a molten Na2CO3 salt containing ZnO as a sulfur-fixing agent was studied. Some influencing factors, including smelting temperature, reaction time, ZnO and salt dosages, were investigated in detail using single-factor experiments. The optimum conditions were determined as follows: T = 880°C; t = 60 min; Na2CO3/paste mass ratio = 2.8:1; and the ZnO dosage is equal to the stoichiometric requirement. Under the optimum conditions, the direct recovery rate of lead reached 98.14%. The results suggested that increases in temperature and salt dosage improved the direct recovery rate of lead. XRD results and thermodynamic calculations indicated that the reaction approaches of lead and sulfur were PbSO4→Pb and PbSO4→ZnS, respectively. Sulfur was fixed in the form of ZnS, whereas the molten salt did not react with other components, serving only as a reaction medium.

  11. Lead acid battery performance and cycle life increased through addition of discrete carbon nanotubes to both electrodes

    NASA Astrophysics Data System (ADS)

    Sugumaran, Nanjan; Everill, Paul; Swogger, Steven W.; Dubey, D. P.

    2015-04-01

    Contemporary applications are changing the failure mechanisms of lead acid batteries. Sulfation at the negative electrode, acid stratification, and dendrite formation now precede positive electrode failures such as grid corrosion and active material shedding. To attenuate these failures, carbon has been explored as a negative electrode additive to increase charge acceptance, eliminate sulfation, and extend cycle life. Frequently, however, carbon incorporation decreases paste density and hinders manufacturability. Discrete carbon nanotubes (dCNT), also known as Molecular Rebar®, are lead acid battery additives which can be stably incorporated into either electrode to increase charge acceptance and cycle life with no change to paste density and without impeding the manufacturing process. Here, full-scale automotive batteries containing dCNT in the negative electrode or both negative and positive electrodes are compared to control batteries. dCNT batteries show little change to Reserve Capacity, improved Cold Cranking, increased charge acceptance, and enhanced overall system efficiency. Life cycle tests show >60% increases when dCNT are incorporated into the negative electrode (HRPSoC/SBA) and up to 500% when incorporated into both electrodes (SBA), with water loss per cycle reduced >20%. Failure modes of cycled batteries are discussed and a hypothesis of dCNT action is introduced: the dCNT/Had Overcharge Reaction Mechanism.

  12. Removal of lead from aqueous solutions by a poly(acrylic acid)/bentonite nanocomposite

    NASA Astrophysics Data System (ADS)

    Rafiei, H. R.; Shirvani, M.; Ogunseitan, O. A.

    2016-11-01

    We synthesized a novel poly acrylic acid-organobentonite (PAA-Bent) nanocomposite by successive intercalation of cetyltrimethylammonium (CTA) surfactant and polyacrylic acid (PAA) into the bentonite (Bent) interlayer spaces. The surfactant-modified clay (CTA-Bent) and PAA-Bent nanocomposite were characterized by XRD and FT-IR techniques and used for removal of Pb(II) from aqueous solution. The XRD results confirmed the intercalation of CTA and PAA into the interlayer spaces of the bentonite increasing the d 001 spacing of the clay from 12.2 up to 38.9 Å. FT-IR analysis of the modified clay samples revealed the functional groups of CTA and PAA constituents alighted on the bentonite surfaces. Maximum Pb sorption capacity of the Bent and PAA-Bent predicted by Langmuir model were 52.3 and 93.0 mg g-1, respectively, showing that the synthesized nanocomposite superiorly adsorbed Pb from the solution as compared to the Bent. The maximum Pb removal efficiency of 99.6 % was achieved by the nanocomposite at 25 °C with <30 min contact time for a 7.5 g L-1 solid-to-liquid ratio and an initial metal concentration of 400 mg L-1. The results indicated that PAA-Bent nanocomposite can be efficiently used as a superadsorbent for the removal of Pb(II) from aqueous solution.

  13. An in situ generated carbon as integrated conductive additive for hierarchical negative plate of lead-acid battery

    NASA Astrophysics Data System (ADS)

    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.

  14. Acid-based balance and blood gas changes in the fresh water field crab, Barytelphusa guerini, on exposure to organic and inorganic lead

    SciTech Connect

    Tulasi, S.J.; Rao, J.V.R.

    1988-02-01

    The acid-base status of crustacean haemolymph depends on various environmental and physiological factors. Acid base status of the haemolymph is known to be influenced by temperature, salinity, strenuous activity and moulting. The studies on the acid-base regulation of the fresh water crabs are meager. The acid-base changes in fishes during environmental stress conditions like acid stress and zinc toxicity had been reported. But the effect of environmental pollutants like the heavy metals on the acid-base regulation of the fresh water crabs have not been previously reported. The haemolymph of the fresh water crab was found to accumulate high amounts of lead on exposure to organic and inorganic lead. Hence the present investigation has been undertaken to study the haemolymph acid-base status on exposure to subtoxic levels of organic and inorganic lead.

  15. Lead dioxide film sonoelectrodeposition in acidic media: Preparation and performance of stable practical anodes.

    PubMed

    Sáez, V; Esclapez, M D; Frías-Ferrer, A J; Bonete, P; Tudela, I; Díez-García, M I; González-García, J

    2011-07-01

    Practical lead dioxide anodes have been obtained by electrodeposition on glassy carbon and titanium substrates in the presence and in the absence of an ultrasound field. The films obtained by mechanical agitation on glassy carbon are strongly improved when the electrodeposition process is carried out with the ultrasound field, providing adherent deposits free from nodules and stress, but with pores appearing occasionally. These enhanced properties were not achieved by mechanical conditions, even when optimization of temperature, current density, additives and geometrical aspects was attempted. The best practical anodes were obtained by sonoelectrodeposition using specially treated titanium as substrate, providing comparable behavior to commercial electrodes.

  16. delta-Aminolevulinic acid dehydratase activity, urinary delta-aminolevulinic acid concentration and zinc protoporphyrin level among people with low level of lead exposure.

    PubMed

    Wang, Qi; Zhao, Huan-hu; Chen, Jian-wei; Hao, Qiao-ling; Gu, Kang-ding; Zhu, Ye-xiang; Zhou, Yi-kai; Ye, Lin-xiang

    2010-01-01

    To evaluate the relationship of delta-aminolevulinic acid dehydratase (ALAD) activity, urinary delta-aminolevulinic acid (ALAU) level and blood zinc protoporphyrin (ZPP) concentration to low blood lead (PbB) levels, these biomarkers were determined for all subjects enrolled from a rural area of southeast China where people had low levels of exposure to lead. The mean values of PbB, ALAD, ALAU and ZPP were 67.11 microg/L (SD: 1.654, range: 10.90-514.04), 339.66 nmol ml(-1)h(-1) (1.419, 78.33-793.13), 20.64 microg/L (1.603, 2.00-326.00), and 0.14 micromol/L (3.437, 0.01-2.26), respectively. ALAD was inversely associated with low levels of PbB. ZPP was inversely related to low levels of PbB but positively related to relatively higher levels of PbB. Alcohol drinking contributed to low ALAD in men. Women had higher ZPP than men. ALAU had no significant association with PbB. In conclusion, ALAD possibly has a non-linear relation with low to moderate levels of PbB. At moderate levels of PbB, ZPP increases with increasing levels of PbB. ALAU is not suitable as an indicator for low levels of lead exposure.

  17. Tissue Doppler Imaging Combined with Advanced 12-Lead ECG Analysis Might Improve Early Diagnosis of Hypertrophic Cardiomyopathy in Childhood

    NASA Technical Reports Server (NTRS)

    Femlund, E.; Schlegel, T.; Liuba, P.

    2011-01-01

    Optimization of early diagnosis of childhood hypertrophic cardiomyopathy (HCM) is essential in lowering the risk of HCM complications. Standard echocardiography (ECHO) has shown to be less sensitive in this regard. In this study, we sought to assess whether spatial QRS-T angle deviation, which has shown to predict HCM in adults with high sensitivity, and myocardial Tissue Doppler Imaging (TDI) could be additional tools in early diagnosis of HCM in childhood. Methods: Children and adolescents with familial HCM (n=10, median age 16, range 5-27 years), and without obvious hypertrophy but with heredity for HCM (n=12, median age 16, range 4-25 years, HCM or sudden death with autopsy-verified HCM in greater than or equal to 1 first-degree relative, HCM-risk) were additionally investigated with TDI and advanced 12-lead ECG analysis using Cardiax(Registered trademark) (IMED Co Ltd, Budapest, Hungary and Houston). Spatial QRS-T angle (SA) was derived from Kors regression-related transformation. Healthy age-matched controls (n=21) were also studied. All participants underwent thorough clinical examination. Results: Spatial QRS-T angle (Figure/ Panel A) and septal E/Ea ratio (Figure/Panel B) were most increased in HCM group as compared to the HCM-risk and control groups (p less than 0.05). Of note, these 2 variables showed a trend toward higher levels in HCM-risk group than in control group (p=0.05 for E/Ea and 0.06 for QRS/T by ANOVA). In a logistic regression model, increased SA and septal E/Ea ratio appeared to significantly predict both the disease (Chi-square in HCM group: 9 and 5, respectively, p less than 0.05 for both) and the risk for HCM (Chi-square in HCM-risk group: 5 and 4 respectively, p less than 0.05 for both), with further increased predictability level when these 2 variables were combined (Chi-square 10 in HCM group, and 7 in HCM-risk group, p less than 0.01 for both). Conclusions: In this small material, Tissue Doppler Imaging and spatial mean QRS-T angle

  18. Recent improvements in PbO2 nanowire electrodes for lead-acid battery

    NASA Astrophysics Data System (ADS)

    Moncada, Alessandra; Piazza, Salvatore; Sunseri, Carmelo; Inguanta, Rosalinda

    2015-02-01

    Lead oxide nanowires are an attractive alternative to conventional pasted electrodes, owing to their high surface area leading to high specific energy batteries. Here, we report the performance of template electrodeposited PbO2 nanowires used as positive electrodes. Nanostructured electrodes were tested at constant charge/discharge rate from 2 C to 10 C, with a cut-off potential of 1.2 V and discharge depth up to 90% of the gravimetric charge. These new type of electrodes are able to work at very high C-rate without fading, reaching an efficiency of about 90% with a very good cycling stability. In particular, after an initial stabilization, a specific capacity of about 200 mAh g-1, very close to the theoretical one of 224 mAh g-1, was drained for more than 1000 cycles at a C-rate higher than 1 C with an efficiency close to 90%. This behaviour significantly distinguishes PbO2 nanostructured electrodes from the conventional ones with pasted active material. In addition, discharge at a quasi-constant voltage of about 2.1 V, without reaching the cut-off potential also at high C-rate, occurs. This implies a quasi-constant energy supply during fast discharge. According to these findings, innovative applications as hybrid or electrical mobility or buffer in renewable energy plants can be envisaged.

  19. Influence of mineral and organic components on copper, lead, and zinc sorption by acid soils.

    PubMed

    Vega, Flora A; Covelo, Emma F; Vázquez, Juan J; Andrade, Luisa

    2007-12-01

    Sorption isotherms were constructed for the sorption of Cu, Pb and Zn by the surface horizons of three soils [a Humic Cambisol (G1), a Haplic Podzol (G2) and an Umbric Gleysol (G3)] and by fractions obtained by sequential removal of organic matter and oxides. All were of L-type except the H-type isotherms recorded for sorption of lead by whole G2, and all were fitted well by the Langmuir model, with determination coefficients > 0.91. Langmuir equation parameter beta correlated well (r(2) = 0.985) with experimentally maximum sorption capacity. For all soils, metal sorption capacities decreased in the order Zn > Cu > Pb. Sorption by organic matter was one of the main contributions to total sorption. Sorption by oxides was generally most substantial in G1, which had the largest total oxides content, while the sorption of lead by G3 was attributable to its high Mn oxides content. The clayey residue contributed significantly to sorption of zinc by G1, and G3 (due to their respective vermiculite and gibbsite contents) and to sorption of copper by G1 due to its vermiculite content.

  20. Saturated fatty acids induce c-Src clustering within membrane subdomains leading to JNK activation

    PubMed Central

    Holzer, Ryan G.; Park, Eek-Joong; Li, Ning; Tran, Helen; Chen, Monica; Choi, Crystal; Solinas, Giovanni; Karin, Michael

    2011-01-01

    Saturated fatty acids (FA) exert adverse health effects and are more likely to cause insulin resistance and type 2 diabetes than unsaturated FA, some of which exert protective and beneficial effects. Saturated FA, but not unsaturated FA, activate Jun N terminal kinase (JNK), which has been linked to obesity and insulin resistance in mice and men. However, it is unknown how saturated and unsaturated FA are discriminated. We now demonstrate that saturated FA activate JNK and induce insulin resistance by altering the membrane distribution of c-Src, causing it to partition into intracellular membrane subdomains where it may become activated. Conversely, unsaturated FA with known beneficial effects on glucose metabolism prevent c-Src membrane partitioning and activation, which are dependent on its myristoylation, and block JNK activation. Consumption of a diabetogenic high fat diet causes the partitioning and activation of c-Src within detergent insoluble membrane subdomains of adipocytes. PMID:21962514

  1. Performic acid (PFA): tests on an advanced primary effluent show promising disinfection performance.

    PubMed

    Gehr, R; Chen, D; Moreau, M

    2009-01-01

    Performic acid, or PFA (CH(2)O(3)), is a well-known oxidizing agent and disinfectant in the medical field and food industry. It has recently become available on a commercial scale for potential use in wastewater disinfection. This study investigated its application to an advanced primary effluent which is recalcitrant to disinfection by UV and peracetic acid (PAA). Methods were developed for determining PFA concentrations in stock solutions as well as in residual concentrations in the wastewater. Batch and continuous-flow pilot studies showed a correlation between log fecal coliform removals and PFA doses. A PFA dose of approximately 3.4 mg/L and a contact time of 45 minutes could achieve 3-logs removal, and almost total disinfection could be achieved using a dose of 6 mg/L. The by-products of PFA addition are hydrogen peroxide and formic acid (CHOOH), neither of which is considered to be toxic to aquatic fauna at the doses required for disinfection.

  2. Combined effects of low-molecular-weight organic acids on mobilization of arsenic and lead from multi-contaminated soils.

    PubMed

    Onireti, Olaronke O; Lin, Chuxia; Qin, Junhao

    2017-03-01

    A batch experiment was conducted to examine the combined effects of three common low-molecular-weight organic acids (LMWOAs) on the mobilization of arsenic and lead in different types of multi-contaminated soils. The capacity of individual LMWOAs (at a same molar concentration) to mobilize soil-borne As and Pb varied significantly. The combination of the organic acids did not make a marked "additive" effect on the mobilization of the investigated three elements. An "antagonistic" effect on element mobilization was clear in the treatments involving oxalic acid for some soils. The acid strength of a LMWOA did not play an important role in controlling the mobilization of elements. While the mobilization of As and Pb was closely associated with the dissolution of soil-borne Fe, soil properties such as original soil pH, organic matter contents and the total amount of the element relative to the total Fe markedly complicated the mobility of that element. Aging led to continual consumption of proton introduced from addition of LMWOAs and consequently caused dramatic changes in solution-borne Fe, which in turn resulted in change in As and Pb in the soil solution though different elements behaved differently.

  3. Effect of a mineral additive on the electrical performances of the positive plate of lead acid battery

    NASA Astrophysics Data System (ADS)

    Foudia, M.; Matrakova, M.; Zerroual, L.

    2015-04-01

    The objective of this work is to improve the performance of the positive electrode of lead-acid battery. The use of the additive in the positive paste is to increase the capacity and cycle life of the positive active material. Mineral porous additives, dispersed uniformly in the PAM, may act as acid reservoirs and favor the ionic diffusion. The results show that the addition of mineral additive in the paste before oxidation influences the composition and the crystal size of the PAM after oxidation. We observe a remarkable improvement of the discharge capacity of the PAM for an amount of additive ranging between 1 and 5%. Nano-sized particles of PbO2 with amorphous character are obtained. XRD, TG and DSC, SEM, and galvanostatic discharge were used as techniques of investigation.

  4. Identification of Scirpus triqueter root exudates and the effects of organic acids on desorption and bioavailability of pyrene and lead in co-contaminated wetland soils.

    PubMed

    Hou, Yunyun; Liu, Xiaoyan; Zhang, Xinying; Chen, Xiao; Tao, Kaiyun; Chen, Xueping; Liang, Xia; He, Chiquan

    2015-11-01

    Root exudates (REs) of Scirpus triqueter were extracted from the rhizosphere soil in this study. The components in the REs were identified by GC-MS. Many organic acids, such as hexadecanoic acid, pentadecanoic acid, vanillic acid, octadecanoic acid, citric acid, succinic acid, glutaric acid, and so on, were found. Batch simulated experiments were conducted to evaluate the impacts of different organic acids, such as citric acid, artificial root exudates (ARE), succinic acid, and glutaric acid in REs of S. triqueter on desorption of pyrene (PYR) and lead (Pb) in co-contaminated wetland soils. The desorption amount of PYR and Pb increased with the rise in concentrations of organic acids in the range of 0-50 g·L(-1), within shaking time of 2-24 h. The desorption effects of PYR and Pb in soils with various organic acids treatments decreased in the following order: citric acid > ARE > succinic acid > glutaric acid. The desorption rate of PYR and Pb was higher in co-contaminated soil than in single pollution soil. The impacts of organic acids in REs of S. triqueter on bioavailability of PYR and Pb suggested that organic acids enhanced the bioavailability of PYR and Pb in wetland soil, and the bioavailability effects of organic acids generally followed the same order as that of desorption effects.

  5. Recent new additives for electric vehicle lead-acid batteries for extending the cycle life and capacity

    SciTech Connect

    Kozawa, A.; Sato, A.; Fujita, K.; Brodd, D.

    1997-12-01

    An electrochemically prepared colloidal graphite was found to be an excellent additive for lead-acid batteries. The new additive extends the capacity and cycle life of new and old batteries and can regenerate old, almost dead, batteries. The colloidal graphite is stable in aqueous solution and the extremely fine particles are adsorbed mainly on the positive electrode. This additive has been given the name, {alpha}-Pholon. The amount required is very small: only 6% to 10% of volume of the {alpha}-Pholon solution (about 2% colloidal graphite in water solution). The beneficial effect of the new additive was demonstrated with motorcycle batteries and forklift batteries.

  6. Development of lead/acid batteries for domestic remote-area power supplies

    NASA Astrophysics Data System (ADS)

    Rand, D. A. J.; Baldsing, W. G. A.

    In recent times, there has been a growing recognition of the need for more reliable RAPS systems, both in Australia and in other parts of the world. From the battery point of view, development has, in some instances, been encouraged by a "market push", and in others by a "technology pull". Some manufacturers are seeking to supply customers with batteries that are merely re-labelled motive-power types, others are offering new technologies. In either case, the suitability of the products is unclear because of the poor comprehension of the actual service requirements imposed on batteries in RAPS operations. In order to overcome this deficiency, CSIRO has set in motion a detailed schedule of laboratory and field studies aimed at gaining a greater understanding of battery performance under RAPS duties. It is hoped that the resulting information will lead to specific design criteria for such batteries.

  7. Advanced Technology Section semiannual progress report, April 1-September 30, 1977. Volume 1. Biotechnology and environmental programs. [Lead Abstract

    SciTech Connect

    Pitt, W.W. Jr.; Mrochek, J.E.

    1980-06-01

    Research efforts in six areas are reported. They include: centrifugal analyzer development; advanced analytical systems; environmental research; bioengineering research;bioprocess development and demonstration; and, environmental control technology. Individual abstracts were prepared for each section for ERA/EDB. (JCB)

  8. Studies on electrolyte formulations to improve life of lead acid batteries working under partial state of charge conditions

    NASA Astrophysics Data System (ADS)

    Hernández, J. C.; Soria, M. L.; González, M.; García-Quismondo, E.; Muñoz, A.; Trinidad, F.

    For decades, valve regulated lead acid batteries with gel electrolyte have proved their excellent performance in deep cycling applications. However, their higher cost, when compared with flooded batteries, has limited their use in cost sensitive applications, such as automotive or PV installations. The use of flooded batteries in deep or partial state of charge working conditions leads to limited life due to premature capacity loss provoked by electrolyte stratification. Different electrolyte formulations have been tested, in order to achieve the best compromise between cost and life performance. Work carried out included electrochemical studies in order to determine the electrolyte stability and diffusional properties, and kinetic studies to check the processability of the electrolyte formulation. Finally, several 12 V batteries have been assembled and tested according to different ageing profiles.

  9. Lead accumulation and depression of delta-aminolevulinic acid dehydratase (ALAD) in young birds fed automotive waste oil

    USGS Publications Warehouse

    Eastin, W.C.; Hoffman, D.J.; O'Leary, C.T.

    1983-01-01

    The effects of a 3-week dietary exposure to automotive waste crankcase oil (WCO) were examined in 1-week-old mallard (Anas platyrhynchos) ducklings and pheasant (Phasianus colchicus) chicks. Treatment groups consisted of birds exposed to 0.5, 1.5, or 4.5% WCO, to 4.5% clean crankcase oil (CCO), or untreated controls. In both species, red blood cell ALAD activity was significantly inhibited after one week by 50 to 60% in the 0.5% WCO group and by 85 to 90% in the 4.5% WCO group due to the presence of lead. Growth, hematocrit, and hemoglobin were not significantly affected at the end of three weeks. Plasma aspartate aminotransferase (AST) activity was higher in mallards after three weeks of ingesting either 4.5% WCO or 4.5% CCO, suggesting an oil-related effect due to components other than lead. Treatment had no effect on plasma concentration of uric acid, glucose, triglycerides, total protein, or cholesterol. Lead analysis showed the WCO to contain 4,200 ppm Pb and the CCO to contain 2 ppm. Tissues of mallards were examined for accumulation of lead and the order of accumulation at the end of three weeks was kidney > liver > blood ~ brain.

  10. Dual effects of acetylsalicylic acid on ERK signaling and Mitf transcription lead to inhibition of melanogenesis.

    PubMed

    Nishio, Takashi; Usami, Mai; Awaji, Mizuki; Shinohara, Sumire; Sato, Kazuomi

    2016-01-01

    Acetylsalicylic acid (ASA) is widely used as an analgesic/antipyretic drug. It exhibits a wide range of biological effects, including preventative effects against heart attack and stroke, and the induction of apoptosis in various cancer cells. We previously found that ASA inhibits melanogenesis in B16 melanoma cells. However, the mechanisms of how ASA down-regulates melanin synthesis remain unclear. Here, we investigated the effect of ASA on melanogenic pathways, such as extracellular signal-regulated kinase (ERK) and microphthalmia-associated transcription factor (Mitf) transcription. ASA significantly inhibited melanin synthesis in a dose-dependent manner without oxidative stress and cell death. Semi-quantitative reverse transcription-polymerase chain reaction analysis showed that the inhibitory effect of ASA might be due to the inhibition of Mitf gene transcription. Interestingly, ASA also induced ERK phosphorylation. Additionally, treatment with PD98059, a specific ERK phosphorylation inhibitor, abolished the anti-melanogenic effect of ASA. These results suggest that the depigmenting effect of ASA results from down-regulation of Mitf, which is induced by both the induction of ERK phosphorylation and the inhibition of Mitf transcription.

  11. Valproic Acid Exposure during Early Postnatal Gliogenesis Leads to Autistic-like Behaviors in Rats

    PubMed Central

    Mony, Tamanna Jahan; Lee, Jae Won; Dreyfus, Cheryl; DiCicco-Bloom, Emanuel; Lee, Hee Jae

    2016-01-01

    Objective We reported that postnatal exposure of rats to valproic acid (VPA) stimulated proliferation of glial precursors during cortical gliogenesis. However, there are no reports whether enhanced postnatal gliogenesis affects behaviors related to neuropsychiatric disorders. Methods After VPA treatment during the postnatal day (PND) 2 to PND 4, four behavioral test, such as open field locomotor test, elevated plus maze test, three-chamber social interaction test, and passive avoidance test, were performed at PND 21 or 22. Results VPA treated rats showed significant hyperactive behavior in the open field locomotor test (p<0.05). Moreover, the velocity of movement in the VPA group was increased by 69.5% (p<0.01). In the elevated plus maze test, VPA exposed rats expressed significantly lower percentage of time spent on and of entries into open arms more than the control group (p<0.05). Also, both sociability and social preference indices with strangers in the three-chamber social interaction test were significantly lower in the VPA exposed rats (p<0.05). Conclusion Our results suggest that altered glial cell development is another locus at which pathogenetic factors can operate to contribute to the neurodevelopmental disorder. PMID:27776385

  12. Ethanol contamination leads to Fatty acid ethyl esters in hair samples.

    PubMed

    De Giovanni, Nadia; Donadio, Giuseppe; Chiarotti, Marcello

    2008-03-01

    The diagnosis of alcoholism is a topical subject of discussion; in fact, many studies have been published on the determination of biochemical markers useful to this target. Fatty acid ethyl esters (FAEE) are minor metabolites of ethanol, and their usefulness has been demonstrated by their detection in hair using a headspace solid-phase microextraction-gas chromatographic-mass spectrometric technique. Environmental contamination in the analysis of drugs of abuse is a well-known focus of discussion between scientists. In the same way, interference from the surroundings could be hypothesized in FAEE detection. To assess the influence of ethanol contamination, an in vitro experiment was performed, leaving hair in an atmosphere saturated with ethanol vapors for 15 days. The spontaneous production of FAEE was demonstrated by analyzing hair day by day. In fact, we observed a constant increase of ethyl myristate, palmitate, and stearate that reached very high concentrations at the end of the investigation. Although the experiment was managed in a stressed way and could not represent real life, its purpose was to focus the attention of researchers on the problem of hair contamination that can occur, for example, with ethanol-containing cosmetics. Therefore, care in interpretation must be taken into account, especially with such a volatile molecule.

  13. Researches on current distribution and plate conductivity of valve-regulated lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Huang, Tao; Ou, Wenjun; Feng, Bo; Huang, Binbin; Liu, Minyi; Zhao, Wenchao; Guo, Yonglang

    2012-07-01

    A cell with tall plates was simulated by two cells and the controlled voltage with time was successfully used to measure the response current-time curves. It indicates that the current in the upper part of the plate is much higher than that in the lower part in early stage of the discharge, but in late stage, it is reversed, especially at high discharge rates. The upper part of the plate has higher capacity and deeper depth of discharge (DOD) so that the active mass degrades and sheds more quickly in cyclic applications. In the initial discharge, the lead sulfate formed at positive plates produces the internal stress and enhances the electric connection among the active mass particles. But the positive active mass only contributes a little to the conductivity of plates. The negative active mass with a bit shrinking but no passivation has better conductivity than the expanded active mass. The higher ohmic polarization of the active mass appears at higher discharge rates, in the upper part of the plates, in the late stage of the discharge, in aged battery, especially for negative plates.

  14. High power valve regulated lead-acid batteries for new vehicle requirements

    NASA Astrophysics Data System (ADS)

    Trinidad, Francisco; Sáez, Francisco; Valenciano, Jesús

    vehicles. However, some development in electrode thickness, separator and electrode corrosion must be made in order to match the performance of new advanced batteries (such as lithium-ion or nickel-metal hydride). Fortunately, the cost advantage of the VRLA technology over other electrochemical couples will continue to be a determinant for the future design of the electrical system of the new vehicles.

  15. Method of preparing a battery paste containing fibrous polyfluoroethylene for use in the plates of a lead-acid storage battery

    SciTech Connect

    Duddy, J.C.; Malaspina, F.P.; Martini, W.J.

    1982-02-16

    A method of preparing a battery paste for a lead-acid storage battery comprising: (A) mixing a water dispersion of polyfluoroethylene with lead material, (B) adding an aqueous solution of sulfuric acid to the lead material-dispersion mix and mixing to form a paste having fibrillation developed therein, (C) controlling the amount of fibrillation developed in the paste, and (D) controlling the paste density for use in a battery plate. The method provides an improved paste which permits substantial reduction in plate weights and density and loss of active material in the grid structure due to plate shedding over a conventional lead-acid paste. The saving in active material ranges from 10 to 30% over a conventional lead-acid paste without reduction in battery performance.

  16. Acid sphingomyelinase (aSMase) deficiency leads to abnormal microglia behavior and disturbed retinal function

    SciTech Connect

    Dannhausen, Katharina; Karlstetter, Marcus; Caramoy, Albert; Volz, Cornelia; Jägle, Herbert; Liebisch, Gerhard; Utermöhlen, Olaf; Langmann, Thomas

    2015-08-21

    Mutations in the acid sphingomyelinase (aSMase) coding gene sphingomyelin phosphodiesterase 1 (SMPD1) cause Niemann-Pick disease (NPD) type A and B. Sphingomyelin storage in cells of the mononuclear phagocyte system cause hepatosplenomegaly and severe neurodegeneration in the brain of NPD patients. However, the effects of aSMase deficiency on retinal structure and microglial behavior have not been addressed in detail yet. Here, we demonstrate that retinas of aSMase{sup −/−} mice did not display overt neuronal degeneration but showed significantly reduced scotopic and photopic responses in electroretinography. In vivo fundus imaging of aSMase{sup −/−} mice showed many hyperreflective spots and staining for the retinal microglia marker Iba1 revealed massive proliferation of retinal microglia that had significantly enlarged somata. Nile red staining detected prominent phospholipid inclusions in microglia and lipid analysis showed significantly increased sphingomyelin levels in retinas of aSMase{sup −/−} mice. In conclusion, the aSMase-deficient mouse is the first example in which microglial lipid inclusions are directly related to a loss of retinal function. - Highlights: • aSMase-deficient mice show impaired retinal function and reactive microgliosis. • aSMase-deficient microglia express pro-inflammatory transcripts. • aSMase-deficient microglia proliferate and have increased cell body size. • In vivo imaging shows hyperreflective spots in the fundus of aSMase-deficient mice. • aSMase-deficient microglia accumulate sphingolipid-rich intracellular deposits.

  17. Spectroscopic evidence for ternary surface complexes in the lead(II)-malonic acid-hematite system

    USGS Publications Warehouse

    Lenhart, J.J.; Bargar, J.R.; Davis, J.A.

    2001-01-01

    Using extended X-ray absorption fine structure (EXAFS) and attenuated total reflectance Fourier-transform infrared (ATR-FTIR) measurements, we examined the sorption of Pb(II) to hematite in the presence of malonic acid. Pb LIII-edge EXAFS measurements performed in the presence of malonate indicate the presence of both Fe and C neighbors, suggesting that a major fraction of surface-bound malonate is bonded to adsorbed Pb(II). In the absence of Pb(II), ATR-FTIR measurements of sorbed malonate suggest the formation of more than one malonate surface complex. The dissimilarity of the IR spectrum of malonate sorbed on hematite to those for aqueous malonate suggest at least one of the sorbed malonate species is directly coordinated to surface Fe atoms in an inner-sphere mode. In the presence of Pb, little change is seen in the IR spectrum for sorbed malonate, indicating that geometry of malonate as it coordinates to sorbed Pb(II) adions is similar to the geometry of malonate as it coordinates to Fe in the hematite surface. Fits of the raw EXAFS spectra collected from pH 4 to pH 8 result in average Pb-C distances of 2.98 to 3.14 A??, suggesting the presence of both four- and six-membered Pb-malonate rings. The IR results are consistent with this interpretation. Thus, our results suggest that malonate binds to sorbed Pb(II) adions, forming ternary metal-bridging surface complexes. ?? 2001 Academic Press.

  18. Highly sensitive colorimetric detection of lead using maleic acid functionalized gold nanoparticles.

    PubMed

    Ratnarathorn, Nalin; Chailapakul, Orawon; Dungchai, Wijitar

    2015-01-01

    Highly sensitive colorimetric detection for Pb(2+) has been developed using maleic acid (MA) functionalized GNP. The -COOH on MA was used to modify GNP surface whereas the other -COOH functional group have strong affinity to coordination behavior of Pb(2+) allowing the selective formation more than other ions. MA-GNPs solution changed from red to blue color after the addition of Pb(2+) due to nanoparticle aggregation. The different optical absorption and discriminate of particle size between the MA-GNPs solution with and without Pb(2+) were characterized by UV-visible spectroscopy and transmission electron microscopy (TEM), respectively. The color intensity as a function of Pb(2+) concentration gave a linear response in the range of 0.0-10.0 µg L(-1) (R(2)=0.990). The detection limit was found at 0.5 µg L(-1) by naked eye and can be completed the analysis within 15 min. The MA-GNPs aggregated with Pb(2+) showed high selectivity when was compared to other metal ions (As(3+), Ca(2+), Cd(2+), Co(2+), Cu(2+), Fe(3+), Hg(2+), Mg(2+), Mn(2+), Ni(2+), Pb(2+) and Zn(2+)) and anions (Cl(-), NO3(-) and SO4(2-)). Our proposed method was also applied for the determination of Pb(2+) in real drinking water samples from 5 sources. The result of real water samples were not statistically significant different from the standard methods at the 95% confidence level (pair t-test method). Moreover, we evaluated our proposed method for the determination of trace Pb(2+) concentration in real breast milk samples. The recoveries were acceptable and ranged from 101 to 104% for spiked Pb(2+) in real breast milk samples. Thus, MA-GNP colorimetric sensing provides a simple, rapid, sensitive, easy-to-use, inexpensive and low detection limit for the monitoring of Pb(2+).

  19. Understory vegetation leads to changes in soil acidity and in microbial communities 27 years after reforestation.

    PubMed

    Fu, Xiaoli; Yang, Fengting; Wang, Jianlei; Di, Yuebao; Dai, Xiaoqin; Zhang, Xinyu; Wang, Huimin

    2015-01-01

    Experiments with potted plants and removed understories have indicated that understory vegetation often affects the chemical and microbial properties of soil. In this study, we examined the mechanism and extent of the influence of understory vegetation on the chemical and microbial properties of soil in plantation forests. The relationships between the vegetational structure (diversity for different functional layers, aboveground biomass of understory vegetation, and species number) and soil properties (pH, microbial community structure, and levels of soil organic carbon, total nitrogen, and inorganic nitrogen) were analyzed across six reforestation types (three pure needleleaf forests, a needle-broadleaf mixed forest, a broadleaf forest, and a shrubland). Twenty-seven years after reforestation, soil pH significantly decreased by an average of 0.95 across reforestation types. Soil pH was positively correlated with the aboveground biomass of the understory. The levels of total, bacterial, and fungal phospholipid fatty acids, and the fungal:bacterial ratios were similar in the shrubland and the broadleaf forest. Both the aboveground biomass of the understory and the diversity of the tree layer positively influenced the fungal:bacterial ratio. Improving the aboveground biomass of the understory could alleviate soil acidification. An increase in the aboveground biomass of the understory, rather than in understory diversity, enhanced the functional traits of the soil microbial communities. The replacement of pure plantations with mixed-species stands, as well as the enhancement of understory recruitment, can improve the ecological functions of a plantation, as measured by the alleviation of soil acidification and increased fungal dominance.

  20. Lead-acid batteries in stationary applications: competitors and new markets for large penetration of renewable energies

    NASA Astrophysics Data System (ADS)

    Perrin, M.; Saint-Drenan, Y. M.; Mattera, F.; Malbranche, P.

    With increasing deregulation of the European electricity market, the quality of supply is becoming an issue of growing importance. Grid-connected electricity storage systems (ESSs) can enhance the quality of supply by: (i) shortening black-out periods; (ii) shifting excess energy for use during periods of high demand; (iii) sustaining the grid for better power quality. These problems are being addressed by using technologies such as power electronics and ICT. But storage systems offer a cheap and efficient solution to such concerns. ESSs can also power high-value, ancillary services. This paper analyses the new potential markets for storage systems in the context of distributed energy resources with a high penetration of renewable energies in the electricity networks. While lead-acid batteries are the most used technology in all types of stationary applications, many different storage technologies are claimed to fulfil the technical requirements of the above applications, in particular the emerging ones. Therefore, a comparison is made of lead-acid technology and its competitors in terms of technical and economic considerations.

  1. Nonlinear phenomenon in monocrystalline silicon based PV module for low power system: Lead acid battery for low energy storage

    NASA Astrophysics Data System (ADS)

    El Amrani, A.; El Amraoui, M.; El Abbassi, A.; Messaoudi, C.

    2014-11-01

    In the present work, we report the indoor photo-electrical measurements of monocrystalline silicon based photovoltaic (PV) module associated with 4 Ah lead acid battery as a storage unit for low power PV system applications. Concerning the PV module, our measurements show, at low illumination regime, that the short circuit current ISC increases linearly with the illumination power levels. Moreover, for high illumination levels, the mechanism of bimolecular recombination and space charge limitation may be intensified and hence the short current of the PV module ISCMod depends sublinearly on the incident optical power; the behavior is nonlinear. For the open circuit voltage of the PV module VOCMod measurements, a linear variation of the VOCMod versus the short circuit current in semi-logarithmic scale has been noticed. The diode ideality factor n and diode saturation current Is have been investigated; the values of n and Is are approximately of 1.3 and 10-9 A, respectively. In addition, we have shown, for different discharging-charging currents rates (i.e. 0.35 A, 0.2 A and 0.04 A), that the battery voltage decreases with discharging time as well as discharging battery capacity, and on the other hand it increases with the charging time and will rise up until it maximized value. The initial result shows the possibility to use such lead acid battery for low power PV system, which is generally designed for the motorcycle battery.

  2. Stannous sulfate as an electrolyte additive for lead acid battery made from a novel ultrafine leady oxide

    NASA Astrophysics Data System (ADS)

    Wang, Qin; Liu, Jianwen; Yang, Danni; Yuan, Xiqing; Li, Lei; Zhu, Xinfeng; Zhang, Wei; Hu, Yucheng; Sun, Xiaojuan; Liang, Sha; Hu, Jingping; Kumar, R. Vasant; Yang, Jiakuan

    2015-07-01

    The effects of SnSO4 as an electrolyte additive on the microstructure of positive plate and electrochemical performance of lead acid battery made from a novel leady oxide are investigated. The novel leady oxide is synthesized through leaching of spent lead paste in citric acid solution. The novel leady oxides are used to prepare working electrode (WE) subjected to electrochemical cyclic voltammetry (CV) tests. Moreover, the novel leady oxides are used as active materials of positive plate assembled as a testing battery of 1.85 A h capacity. In CV tests, SEM/EDX results show that the major crystalline phase of the paste in WE after CV cycles is PbSO4. The larger column-shaped PbSO4 crystals easily generate in the paste of WE without an electrolyte additive of SnSO4. However, PbSO4 crystals significantly become smaller with the addition of SnSO4 in the electrolyte. In batteries testing, SEM results show that an electrolyte additive of SnSO4 could effectively decrease PbO2 particle size in the positive active materials of the teardown battery at the end of charging procedure. It is indicated that an electrolyte additive of SnSO4 could have a positive influence on restraining larger particles of irreversible sulfation in charge/discharge cycles of battery testing.

  3. Frequency and Temperature Characteristics of an Ultrasonic Method for Measuring the Specific Gravity of Lead-Acid Battery Electrolyte

    NASA Astrophysics Data System (ADS)

    Liu, Jiaxin; Li, Guofeng

    2012-02-01

    In this paper, we present an ultrasonic method for measuring the specific gravity of lead-acid battery electrolyte and study its frequency and temperature characteristics. This method uses an improved frequency scanning ultrasonic pulse echo reflectometer with a two-transducer configuration. The velocity and attenuation coefficient (1 to 30 MHz) of electrolytes with different specific gravities (1.05 to 1.30) are obtained at 25 °C. It has been shown that the ultrasonic velocity changes little with frequency, and there is low attenuation at approximately 5 MHz. The velocities of several electrolytes with different specific gravities are measured in the temperature range from 10 to 50 °C. The thermal transient of the measurement cell is analyzed, showing 0.1% accuracy in specific gravity measurement for a steady temperature and 0.5% accuracy under thermal gradient conditions after temperature compensation. This method is suitable for the on-line, rapid, and accurate measurement of the specific gravity of a lead-acid battery electrolyte.

  4. Cell/dendrite transition and electrochemical corrosion of Pb-Sb alloys for lead-acid battery applications

    NASA Astrophysics Data System (ADS)

    Osório, Wislei R.; Rosa, Daniel M.; Peixoto, Leandro C.; Garcia, Amauri

    2011-08-01

    The aim of this article is focused on a comparative experimental study of the electrochemical feature of as-cast Pb-2.2 wt.% Sb alloy with cellular/dendritic transition for applications in the manufacturing of lead-acid battery parts. A water-cooled unidirectional solidification system is used to obtain the alloy samples. Electrochemical impedance spectroscopy (EIS) plots, potentiodynamic polarization curves and equivalent circuit analysis are used to evaluate corrosion resistance in a 0.5 M H2SO4 solution at 25 °C. The cellular Pb-2.2 wt.% Sb alloy is found to have a current density which is of about 3 times lower than that of the dendritic Pb-2.2 wt.% Sb alloy. The Pb-2.2 wt.% Sb alloy has lower current density than both the Pb-1 wt.% Sb and the Pb-6.6 wt.% Sb alloys evidencing its potential for application as positive grid material in lead-acid batteries. It is also verified that a conventional casting with low cooling rate of about 0.6 °C s-1 produces coarser cellular spacings which is more appropriate for the manufacturing of the Pb-2.2 wt.% Sb alloys grids due to its corresponding electrochemical behavior.

  5. Study on titanium foil coated with partial reduction titanium dioxide as bipolar lead-acid battery's substrate

    NASA Astrophysics Data System (ADS)

    Lang, Xiaoshi; Wang, Dianlong; Tang, Shenzhi; Zhu, Junsheng; Guo, Chenfeng

    2014-12-01

    Pure titanium foil cannot be directly as the substrate for the bipolar lead-acid battery due to its surface oxidized into titanium dioxide in the cell cycle. The poor electronic conductivity of titanium dioxide will increase substrate's ohmic resistance and can affect the cell's electrochemical performances. In this paper, titanium foil's surface is coated with a lay of partial reduction titanium dioxide (TiO2-x) which has excellent chemical stability and high electronic conductivity by means of sol-gel method. Through XRD, SEM and four-probe test, it shows that the modified titanium's surface has the most superior crystal structure and morphology and the highest electronic conductivity in the sintering temperature of 800 °C. We subsequently assemble bipolar lead-acid batteries with Ti coated by TiO2-x as the substrate material. The batteries are discovered that when charged and discharged in 3.5 V-4.84 V at 0.5C the voltage between the charge and discharge voltage platform is 0.3 V, and the initial discharge specific capacity can reach 80 mAh g-1. When the current rate is up to 1C and 2C, the initial discharge specific capacity is 70 mAh g-1and 60 mAh g-1. After 100 cycles, the initial specific capacity only decreases 12.5%.

  6. Battery energy-storage systems — an emerging market for lead/acid batteries

    NASA Astrophysics Data System (ADS)

    Cole, J. F.

    Although the concept of using batteries for lead levelling and peak shaving has been known for decades, only recently have these systems become commercially viable. Changes in the structure of the electric power supply industry have required these companies to seek more cost-effective ways of meeting the needs of their customers. Through experience gained, primarily in the USA, batteries have been shown to provide multiple benefits to electric utilities. Also, lower maintenance batteries, more reliable electrical systems, and the availability of methods to predict costs and benefits have made battery energy-storage systems more attractive. Technology-transfer efforts in the USA have resulted in a willingness of electric utilities to install a number of these systems for a variety of tasks, including load levelling, peak shaving, frequency regulation and spinning reserve. Additional systems are being planned for several additional locations for similar applications, plus transmission and distribution deferral and enhanced power quality. In the absence of US champions such as the US Department of Energy and the Electric Power Research Institute, ILZRO is attempting to mount a technology-transfer programme to bring the benefits of battery energy-storage to European power suppliers. As a result of these efforts, a study group on battery energy-storage systems has been established with membership primarily in Germany and Austria. Also, a two-day workshop, prepared by the Electric Power Research Institute was held in Dublin. Participants included representatives of several European power suppliers. As a result, ESB National Grid of Ireland has embarked upon a detailed analysis of the costs and benefits of a battery energy-storage system in their network. Plans for the future include continuation of this technology-transfer effort, assistance in the Irish effort, and a possible approach to the European Commission for funding.

  7. The Use of Pristine and Intercalated Graphite Fiber Composites as Buss Bars in Lead-Acid Batteries

    NASA Technical Reports Server (NTRS)

    Opaluch, Amanda M.

    2004-01-01

    This study was conducted as a part of the Firefly Energy Space Act Agreement project to investigate the possible use of composite materials in lead acid batteries. Specifically, it examined the use of intercalated graphite composites as buss bars. Currently, buss bars of these batteries are made of lead, a material that is problematic for several reasons. Over time, the lead is subject to both corrosion at the positive plate and sulfation at the negative plate, resulting in decreased battery life. In addition, the weight and size of the lead buss bars make for a heavy and cumbersome battery that is undesirable. Functionality and practicality of lead buss bars is adequate at best; consequently, investigation of more efficient composite materials would be advantageous. Practically speaking, graphite composites have a low density that is nearly one fourth that of its lead counterpart. A battery made of less dense materials would be more attractive to the consumer and the producer because it would be light and convenient. More importantly, low weight would be especially beneficial because it would result in greater overall power density of the battery. In addition to power density, use of graphite composite materials can also increase the life of the battery. From a functional standpoint, corrosion and sulfation at the positive and negative plates are major obstacles when considering how to extend battery life. Neither of these reactions are a factor when graphite composites replace lead parts because graphite is chemically non-reactive with the electrolyte within the battery. Without the problem of corrosion or sulfation, battery life expectancy can be almost doubled. The replacement of lead battery parts with composite materials is also more environmentally favorable because of easy disposal of organic materials. For this study, both pristine and bromine intercalated single-ply graphite fiber composites were created. The composites were fabricated in such a way as to

  8. Benzene exposure, assessed by urinary trans,trans-muconic acid, in urban children with elevated blood lead levels.

    PubMed Central

    Weaver, V M; Davoli, C T; Heller, P J; Fitzwilliam, A; Peters, H L; Sunyer, J; Murphy, S E; Goldstein, G W; Groopman, J D

    1996-01-01

    A pilot study was performed to evaluate the feasibility of using trans,trans-muconic acid (MA) as a biomarker of environmental benzene exposure. A secondary aim was to provide data on the extent of exposure to selected toxicants in a unique population consisting of inner-city children who were already overexposed to one urban hazard, lead. Potential sources of benzene were assessed by a questionnaire. Exposure biomarkers included urinary MA and cotinine and blood lead. Mean MA was 176.6 +/- 341.7 ng/mg creatinine in the 79 children who participated. A wide range of values was found with as many as 10.1%, depending on the comparison study, above the highest levels reported in adults not exposed by occupation. Mean MA was increased in children evaluated in the afternoon compared to morning, those at or above the median for time spent playing near the street, and those studied in the first half of the investigation. MA levels were not associated with blood lead or, consistently, with either questionnaire environmental tobacco smoke (ETS) data or cotinine. As expected, the mean blood lead level was elevated (23.6 micrograms/dl). Mean cotinine was also increased at 79.2 ng/mg creatinine. We conclude that the use of MA as a biomarker for environmental benzene exposure is feasible since it was detectable in 72% of subjects with a wide range of values present. In future studies, correlation of MA with personal air sampling in environmental exposure will be essential to fully interpret the significance of these findings. In addition, these inner-city children comprise a high risk group for exposure to environmental toxicants including ETS, lead, and probably benzene, based on questionnaire sources and its presence in ETS. Images Figure 1. Figure 2. Figure 3. Figure 4. Figure 4. Figure 5. PMID:8919771

  9. Health hazards of China’s lead-acid battery industry: a review of its market drivers, production processes, and health impacts

    PubMed Central

    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

  10. Effects of lead on delta-aminolevulinic acid dehydratase activity, growth, hemoglobin content, and reproduction in Daphnia magna

    SciTech Connect

    Berglind, R.; Dave, G.; Sjoebeck, M.L.

    1985-04-01

    The effects of continuous exposure to lead for various periods and recovery in clean water on delta-aminolevulinic acid dehydratase (ALA-D) activity, hemoglobin content, growth, and reproduction were studied in Daphnia magna. Steady-state inhibition of ALA-D activity was reached within 2 days in 16, 64, and 256 micrograms Pb liter-1, but restoration in clean water was prolonged in relation to previous exposure. In spite of the inhibition of ALA-D activity hemoglobin content increased after 2 days in 16 and 24 micrograms Pb liter-1. Furthermore, hemoglobin content in previously exposed animals increased during recovery in clean water. Maximum hemoglobin content (2.9 times control value) was found after 2 days recovery of animals exposed to 64 micrograms Pb liter-1. These findings suggest that some enzyme(s) other than ALA-D in the biosynthetic pathway of hemoglobin formation is (are) more sensitive to lead. Growth, in contrast to reproduction, was stimulated by low concentrations of lead (less than 64 micrograms Pb liter-1), although in 256 micrograms Pb liter-1 growth was also significantly impaired. After 19 days the 16 and 50% reproductive impairment concentrations were less than or equal to 1 and 10 micrograms Pb liter-1, respectively.

  11. Distribution of soil arsenic species, lead and arsenic bound to humic acid molar mass fractions in a contaminated apple orchard.

    PubMed

    Newton, Kimberly; Amarasiriwardena, Dulasiri; Xing, Baoshan

    2006-09-01

    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.

  12. Enhanced performance of Zn(II)-doped lead-acid batteries with electrochemical active carbon in negative mass

    NASA Astrophysics Data System (ADS)

    Xiang, Jiayuan; Hu, Chen; Chen, Liying; Zhang, Dong; Ding, Ping; Chen, Dong; Liu, Hao; Chen, Jian; Wu, Xianzhang; Lai, Xiaokang

    2016-10-01

    The effect and mechanism of Zn(II) on improving the performances of lead-acid cell with electrochemical active carbon (EAC) in negative mass is investigated. The hydrogen evolution of the cell is significantly reduced due to the deposition of Zn on carbon surface and the increased porosity of negative mass. Zn(II) additives can also improve the low-temperature and high-rate capacities of the cell with EAC in negative mass, which ascribes to the formation of Zn on lead and carbon surface that constructs a conductive bridge among the active mass. Under the co-contribution of EAC and Zn(II), the partial-state-of-charge cycle life is greatly prolonged. EAC optimizes the NAM structure and porosity to enhance the charge acceptance and retard the lead sulfate accumulation. Zn(II) additive reduces the hydrogen evolution during charge process and improves the electric conductivity of the negative electrode. The cell with 0.6 wt% EAC and 0.006 wt% ZnO in negative mass exhibits 90% reversible capacity of the initial capacity after 2100 cycles. In contrast, the cell with 0.6 wt% EAC exhibits 84% reversible capacity after 2100 cycles and the control cell with no EAC and Zn(II) exhibits less than 80% reversible capacity after 1350 cycles.

  13. Folic acid protects against lead acetate-induced hepatotoxicity by decreasing NF-κB, IL-1β production and lipid peroxidation mediataed cell injury.

    PubMed

    Abd Allah, Eman S H; Badary, Dalia M

    2017-03-01

    Folic acid plays an important role in cellular metabolic activities. The present study was designed to investigate the protective effect of folic acid against lead acetate-induced hepatotoxicity. Twenty four male Wistar albino rats were randomly divided into four groups, six animals each. Negative control group received the vehicle, positive control group received 1mg/kg folic acid for five consecutive days/week for 4 weeks orally, lead-exposed group received 10mg/kg lead acetate intraperitoneally (IP) for five consecutive days/week for 4 weeks, and lead-treated group received 10mg/kg lead acetate IP and 1mg/kg folic acid orally for five consecutive days/week for 4 weeks concurrently. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and γ- glutamyltransferase (GGT) were measured. Hepatic total peroxide and interleukin-1β (IL-1β) were also investigated. Histopathological studies using hematoxylin-eosin (H&E) and periodic acid shiff's (PAS) were carried out. The expression of nuclear factor kappa B (NF-κB) was evaluated using immunohistochemistry. Serum AST, ALT and GGT and hepatic total peroxide and IL-1β were significantly increased in lead-exposed group and were positively correlated with hepatic lead level. Moreover, lead-exposed rats showed hydropic degeneration, nuclear vesiculation, high lymphocytic infiltration, depletion of glycogen content and NF-κB expression. Concomitant folic acid administration resulted in a significant alleviation of biochemical and structural alteration-induced by lead. This was associated with reduction of hepatic total peroxide and IL-1β and reduction of NF-κB expression. In conclusion, folic acid protects against lead acetate-induced hepatotoxicity by decreasing NF-κB, IL-1β production and lipid peroxidation mediataed cell injury.

  14. Design optimization of tall tubular lead/acid cells based on an analysis of the reaction distribution

    NASA Astrophysics Data System (ADS)

    Asai, Kenji; Hatanaka, Teruhiro; Tsubota, Masaharu; Yonezu, Kunio; Ando, Koji

    In order to estimate the discharge performance of tall lead/acid cells (with tubular positives), changes in current and potential distributions with discharge progress were calculated with a computer on the basis of plate resistance and the current—potential—time relationship between small facing parts of positive and negative plates. The taller the cell, the larger the voltage drop along the plates. Thus, the discharge time became shorter despite a large amount of available active mass remaining in the bottom part of the plates. Various current-collector designs were evaluated, e.g., one with varying resistance at each height; a side conductor placed along the plates and connected to them at the top, centre and bottom, etc. Results revealed an optimum collector design with which the maximum discharge capacity could be obtained. Furthermore, it was shown that the side conductor markedly improved the discharge performance because the active mass near the connecting parts was appreciably used.

  15. Recent Advances in Substrate-Controlled Asymmetric Induction Derived from Chiral Pool α-Amino Acids for Natural Product Synthesis.

    PubMed

    Paek, Seung-Mann; Jeong, Myeonggyo; Jo, Jeyun; Heo, Yu Mi; Han, Young Taek; Yun, Hwayoung

    2016-07-21

    Chiral pool α-amino acids have been used as powerful tools for the total synthesis of structurally diverse natural products. Some common naturally occurring α-amino acids are readily available in both enantiomerically pure forms. The applications of the chiral pool in asymmetric synthesis can be categorized prudently as chiral sources, devices, and inducers. This review specifically examines recent advances in substrate-controlled asymmetric reactions induced by the chirality of α-amino acid templates in natural product synthesis research and related areas.

  16. Regulatory mechanism of gallic acid against advanced glycation end products induced cardiac remodeling in experimental rats.

    PubMed

    Umadevi, Subramanian; Gopi, Venkatachalam; Elangovan, Vellaichamy

    2014-02-05

    Advanced glycation end products (AGEs) play a major role in the development of cardiovascular disorders in diabetic patients. Recent studies evidenced the beneficial role of phytochemicals in reducing the risk of cardiovascular diseases. Hence the present study was framed to investigate the protective role of Gallic acid (GA) on AGEs induced cardiac fibrosis. Rats were infused with in vitro prepared AGEs (50mg/kg BW-intravenous injection) for 30 days. Further, GA (25mg/kgBW) was administered to rats along with AGEs. On infusion of AGEs, induction of fibrotic markers, collagen deposition, oxidative marker NADPH oxidase (NOX-p47 phox subunit), AGE receptor (RAGE) and cytokines expression was evaluated in the heart tissues using RT-PCR, Western blot and immunostaining methods. AGEs infusion significantly (P<0.01) increased the HW/BW ratio and fibrosis (4-fold) with increased expression of matrix genes MMP-2 and -9 (P<0.01, respectively) in the heart tissues. Whereas, administration of GA along with AGEs infusion prevented the fibrosis induced by AGEs. Further, GA treatment effectively prevented the AGEs mediated up-regulation of pro-fibrotic genes and ECM proteins such as TNF-α, TGF-β, MMP-2 and -9 expression. In addition, the increased expression of NOX (P<0.01), RAGE (P<0.01), NF-κB (P<0.01) and ERK 1/2 on AGEs infusion were normalized by GA treatment. Thus the present study shows the protective effect of GA on the fibrotic response and cardiac remodeling process induced by advanced glycation end products from external sources.

  17. Toxic effects on bioaccumulation and hematological parameters of juvenile rockfish Sebastes schlegelii exposed to dietary lead (Pb) and ascorbic acid.

    PubMed

    Kim, Jun-Hwan; Kang, Ju-Chan

    2017-02-20

    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.

  18. A novel magnetic field probing technique for determining state of health of sealed lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Khare, Neeta; Singh, Pritpal; Vassiliou, John K.

    2012-11-01

    State of Health (SOH) is a critical index for a Sealed Lead-Acid (SLA) battery diagnostic which provides the information about battery replacement and aging effects. SOH is a complex function of chemical parameters of a battery such as stratification in electrolyte, electrode structure (sulfation and hard sulfation) in addition to electrical parameters of a battery. This paper describes a method of online determination of stratification, electrode structure, electrode polarization and current profile within the battery under the influence of a magnetic field. An AC magnetic field is used as a noninvasive tool during battery cycles. An induced emf in a secondary coil (SCV) is used as a measure of change in the magnetic field. The H+ proton density varies with change in sulfuric acid (electrolyte) concentration during battery cycles. The magnetic flux lines are affected by the density of H+ protons whose magnetic dipole moments try to align along the magnetic flux lines. The stratification is seen by a 12% decrease in magnetic flux linking from the top to the bottom of the electrolyte in a battery. Additional experimental results demonstrate the variation in magnetic flux linking which correlates with current profile across the electrode and electrode structure.

  19. Research, development, and demonstration of lead-acid batteries for electric vehicle propulsion. Annual report for 1980

    SciTech Connect

    Not Available

    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.

  20. The effect of tannic acid on the bone tissue of adult male Wistar rats exposed to cadmium and lead.

    PubMed

    Tomaszewska, Ewa; Dobrowolski, Piotr; Winiarska-Mieczan, Anna; Kwiecień, Małgorzata; Tomczyk, Agnieszka; Muszyński, Siemowit

    2017-03-02

    Toxic elements such as cadmium (Cd) and lead (Pb) accumulate to the largest extent in bones. Rats at the age of 12 weeks were used to check whether tannic acid (TA) at the concentration of 0.5%, 1.0%, 1.5%. 2.0% or 2.5% would have a protective effect on the structure and properties of bones in the case of exposure to Cd and Pb (diet: 7mg Cd/kg and 50mg Pb/kg) for 12 weeks. The effects of administration of TA in Cd- and Pb-poisoned rats on bone mechanical and geometric properties, trabecular histomorphometry as well as the morphology of articular and growth cartilages were determined. All the rats co-exposured to Cd and Pb had enhanced heavy metals concentration in blood plasma and bone and reduced bone Ca content irrespective of the tannic acid administration. Heave metals given to adult rats did not influence the morphology and geometry of the femur, but reduced the mechanical endurance and histomorphometric parameters of trabecular bone irrespective of the treatment. A diet rich in TA improved articular cartilage and growth plate constituents in heavy metal-poisoned rats, as indicated by the measurement of the thickness of particular zones. It seems that a use of alimentary TA supplementation in adult rats can counteract, in a dose-dependent manner, only some of the destructive changes evoked by Cd and Pb excess.

  1. Lead-acid battery

    NASA Technical Reports Server (NTRS)

    Edwards, Dean B. (Inventor); Rippel, Wally E. (Inventor)

    1986-01-01

    A sealed, low maintenance battery (10, 100) is formed of a casing (14, 102) having a sealed lid (12, 104) enclosing cell compartments (22, 110) formed by walls (24, 132). The cells comprise a stack (26) of horizontally disposed negative active plates (30) and positive active plates (28) interspersed with porous, resilient separator sheets (30). Each plate has a set of evenly spaced tigs (40, 41) disposed on one side thereof; like polarity tigs being disposed on one side and opposite polarity tigs on the other. Columns of tigs are electrically and mechanically joined by vertical bus bars (46). The bus bars contain outwardly projecting arms (56) of opposite polarity which are electrically joined at each partition wall (24) to electrically connect the cells in series. The stack is compressed by biasing means such as resilient pad (58) attached to the lid or by joining the tigs (52) to the post (48) at a distance less than the thickness of the mat (124). The end bus bars (46) are joined to straps (60, 62) which connect to the terminals (16, 18). The negative plates contain more capacity than the positive plates and the starved electrolyte imbibed in the separator sheets permits pressurized operation during which oxygen diffuses through the separator sheet to the negative plate where it recombines. Excess pressure is relieved through the vent and pressure relief valve (20).

  2. Role of electrical resistance of electrodes in modeling of discharging and charging of flooded lead-acid batteries

    NASA Astrophysics Data System (ADS)

    Gandhi, K. S.

    2015-03-01

    Electrical resistance of both the electrodes of a lead-acid battery increases during discharge due to formation of lead sulfate, an insulator. Work of Metzendorf [1] shows that resistance increases sharply at about 65% conversion of active materials, and battery stops discharging once this critical conversion is reached. However, these aspects are not incorporated into existing mathematical models. Present work uses the results of Metzendorf [1], and develops a model that includes the effect of variable resistance. Further, it uses a reasonable expression to account for the decrease in active area during discharge instead of the empirical equations of previous work. The model's predictions are compared with observations of Cugnet et al. [2]. The model is as successful as the non-mechanistic models existing in literature. Inclusion of variation in resistance of electrodes in the model is important if one of the electrodes is a limiting reactant. If active materials are stoichiometrically balanced, resistance of electrodes can be very large at the end of discharge but has only a minor effect on charging of batteries. The model points to the significance of electrical conductivity of electrodes in the charging of deep discharged batteries.

  3. Modeling of the cranking and charging processes of conventional valve regulated lead acid (VRLA) batteries in micro-hybrid applications

    NASA Astrophysics Data System (ADS)

    Gou, Jun; Lee, Anson; Pyko, Jan

    2014-10-01

    The cranking and charging processes of a VRLA battery during stop-start cycling in micro-hybrid applications were simulated by one dimensional mathematical modeling, to study the formation and distribution of lead sulfate across the cell and analyze the resulting effect on battery aging. The battery focused on in this study represents a conventional VRLA battery without any carbon additives in the electrodes or carbon-based electrodes. The modeling results were validated against experimental data and used to analyze the "sulfation" of negative electrodes - the common failure mode of lead acid batteries under high-rate partial state of charge (HRPSoC) cycling. The analyses were based on two aging mechanisms proposed in previous studies and the predictions showed consistency with the previous teardown observations that the sulfate formed at the negative interface is more difficult to be converted back than anywhere else in the electrodes. The impact of cranking pulses during stop-start cycling on current density and the corresponding sulfate layer production was estimated. The effects of some critical design parameters on sulfate formation, distribution and aging over cycling were investigated, which provided guidelines for developing models and designing of VRLA batteries in micro-hybrid applications.

  4. Ascorbic acid deficiency leads to increased grain chalkiness in transgenic rice for suppressed of L-GalLDH.

    PubMed

    Yu, Le; Liu, Yonghai; Lu, Lina; Zhang, Qilei; Chen, Yezheng; Zhou, Liping; Chen, Hua; Peng, Changlian

    2017-04-01

    The grain chalkiness of rice (Oryza sativa L.), which determines the rice quality and price, is a major concern in rice breeding. Reactive oxygen species (ROS) plays a critical role in regulating rice endosperm chalkiness. Ascorbic acid (Asc) is a major plant antioxidant, which strictly regulates the levels of ROS. l-galactono-1, 4-lactone dehydrogenase (L-GalLDH, EC 1.3.2.3) is an enzyme that catalyzes the last step of Asc biosynthesis in higher plants. Here we show that the L-GalLDH-suppressed transgenic rice, GI-1 and GI-2, which have constitutively low (between 30% and 50%) leaf and grain Asc content compared with the wild-type (WT), exhibit significantly increased grain chalkiness. Further examination showed that the deficiency of Asc resulted in a higher lipid peroxidation and H2O2 content, accompanied by a lower hydroxyl radical scavenging rate, total antioxidant capacity and photosynthetic ability. In addition, changes of the enzyme activities and gene transcript abundances related to starch synthesis were also observed in GI-1 and GI-2 grains. The results we presented here suggest a close correlation between Asc deficiency and grain chalkiness in the L-GalLDH-suppressed transgenics. Asc deficiency leads to the accumulation of H2O2, affecting antioxidant capacity and photosynthetic function, changing enzyme activities and gene transcript abundances related to starch synthesis, finally leading to the increased grain chalkiness.

  5. EFFECT OF INDOLE-3-ACETIC ACID, KINETIN, AND ETHYLENEDIAMINETETRAACETIC ACID ON PLANT GROWTH AND UPTAKE AND TRANSLOCATION OF LEAD, MICRONUTRIENTS, AND MACRONUTRIENTS IN ALFALFA PLANTS.

    PubMed

    López, Martha Laura; Peralta-Videa, José R; Parsons, Jason G; Gardea-Torresdey, Jorge L; Duarte-Gardea, Maria

    2009-02-01

    Alfalfa plants germinated and grown for 15 d in soil containing 80 mg Pb kg(-1) were treated with ethylenediaminetetraacetic acid (EDTA) at 0.8 mM and indole-3-acetic acid-kinetin (IAA-KN) at 100 μM. Fifteen days after the treatment application, the concentration of lead (Pb), macronutrients, and micronutrients was determined using inductively coupled plasma/optical emission spectroscopy. The chlorophyll content and plant growth were also measured. Roots of plants exposed to Pb alone, Pb-EDTA, and Pb-EDTA-IAA-KN had 160, 140, and 150 mg Pb kg(-1) DW, respectively. Pb was not detected in the stems of plants exposed to Pb alone; however, stems of plants treated with EDTA and EDTA-IAA-KN had 78 and 142 mg Pb kg(-1) DW, respectively. While the Pb concentration in leaves of plants treated with EDTA and EDTA-IAA-KN was 92 and 127 mg kg(-1) DW, respectively. In addition, EDTA and EDTA-IAA-KN significantly increased the translocation of zinc and manganese to leaves. The x-ray absorption spectroscopic studies demonstrated that Pb(II) was transported from roots to leaves without a change in the oxidation state.

  6. Librarian-lead tutorial for enhancement of pharmacy students' information-searching skills in advanced experiential rotations.

    PubMed

    Lapidus, Mariana; Kostka-Rokosz, Maria D; Dvorkin-Camiel, Lana

    2009-10-01

    Pharmacy schools across the United States expose students to literature searching and evaluation mostly during required didactic drug information courses. The majority of Doctor of Pharmacy (PharmD) students do not utilize library-available electronic resources on a regular basis, and their didactic experience alone is not sufficient to make them successful in their advanced experiential drug information (DI) rotations. This pilot study demonstrates an improvement of students' perceptions regarding information searching and evaluating abilities as the result of their participation in a small group tutorial with a reference librarian, thus indicating effectiveness of the tutorial in refreshing and enhancing database knowledge skills.

  7. Biosynthesis of Polyunsaturated Fatty Acids in Marine Invertebrates: Recent Advances in Molecular Mechanisms

    PubMed Central

    Monroig, Óscar; Tocher, Douglas R.; Navarro, Juan C.

    2013-01-01

    Virtually all polyunsaturated fatty acids (PUFA) originate from primary producers but can be modified by bioconversions as they pass up the food chain in a process termed trophic upgrading. Therefore, although the main primary producers of PUFA in the marine environment are microalgae, higher trophic levels have metabolic pathways that can produce novel and unique PUFA. However, little is known about the pathways of PUFA biosynthesis and metabolism in the levels between primary producers and fish that are largely filled by invertebrates. It has become increasingly apparent that, in addition to trophic upgrading, de novo synthesis of PUFA is possible in some lower animals. The unequivocal identification of PUFA biosynthetic pathways in many invertebrates is complicated by the presence of other organisms within them. These organisms include bacteria and algae with PUFA biosynthesis pathways, and range from intestinal flora to symbiotic relationships that can involve PUFA translocation to host organisms. This emphasizes the importance of studying biosynthetic pathways at a molecular level, and the continual expansion of genomic resources and advances in molecular analysis is facilitating this. The present paper highlights recent research into the molecular and biochemical mechanisms of PUFA biosynthesis in marine invertebrates, particularly focusing on cephalopod molluscs. PMID:24152561

  8. Oral essential amino acid supplements in children with advanced chronic renal failure.

    PubMed

    Jones, R W; Dalton, N; Start, K; El-Bishti, M M; Chantler, C

    1980-07-01

    The effects on growth, nitrogen balance, and body composition of a protein-restricted diet supplemented with oral essential amino acids (EAA) were studied in seven children with advanced chronic renal failure. The diet was designed to provide minimum protein requirements for height-age, half in unselected form and half as an EAA supplement. Energy from carbohydrate and fat were increased to give a protein/energy ratio of 1.25 G:100 kcal. Nitrogen balance, studied in five children before and after 6 to 8 months of EAA treatment, was improved in each case. intracellular water (total body water minus bromide space) increased in four children but fell in three children during treatment. No significant improvement in growth, expressed as height or height velocity standard deviation scores in relation to bone age, was observed. Serum urea and urea/creatinine ratio fell after institution of EAA treatment, but the fall was not sustained. Although the EAA preparation proved acceptable to the children, dietary assessments indicated that the desired dietary aims were rarely achieved. It is concluded that, in this pediatric age group, the long-term application of a protein restricted diet with EAA supplements is of limited value.

  9. Biosynthesis of polyunsaturated fatty acids in marine invertebrates: recent advances in molecular mechanisms.

    PubMed

    Monroig, Óscar; Tocher, Douglas R; Navarro, Juan C

    2013-10-21

    Virtually all polyunsaturated fatty acids (PUFA) originate from primary producers but can be modified by bioconversions as they pass up the food chain in a process termed trophic upgrading. Therefore, although the main primary producers of PUFA in the marine environment are microalgae, higher trophic levels have metabolic pathways that can produce novel and unique PUFA. However, little is known about the pathways of PUFA biosynthesis and metabolism in the levels between primary producers and fish that are largely filled by invertebrates. It has become increasingly apparent that, in addition to trophic upgrading, de novo synthesis of PUFA is possible in some lower animals. The unequivocal identification of PUFA biosynthetic pathways in many invertebrates is complicated by the presence of other organisms within them. These organisms include bacteria and algae with PUFA biosynthesis pathways, and range from intestinal flora to symbiotic relationships that can involve PUFA translocation to host organisms. This emphasizes the importance of studying biosynthetic pathways at a molecular level, and the continual expansion of genomic resources and advances in molecular analysis is facilitating this. The present paper highlights recent research into the molecular and biochemical mechanisms of PUFA biosynthesis in marine invertebrates, particularly focusing on cephalopod molluscs.

  10. Analysis of leading edge and trailing edge cover glass samples before and after treatment with advanced satellite contamination removal techniques

    NASA Technical Reports Server (NTRS)

    Hotaling, S. P.

    1993-01-01

    Two samples from Long Duration Exposure Facility (LDEF) experiment M0003-4 were analyzed for molecular and particulate contamination prior to and following treatment with advanced satellite contamination removal techniques (CO2 gas/solid jet spray and oxygen ion beam). The pre- and post-cleaning measurements and analyses are presented. The jet spray removed particulates in seconds. The low energy reactive oxygen ion beam removed 5,000 A of photo polymerized organic hydrocarbon contamination in less than 1 hour. Spectroscopic analytical techniques were applied to the analysis of cleaning efficiency including: Fourier transform infrared, Auger, x ray photoemissions, energy dispersive x ray, and ultraviolet/visible. The results of this work suggest that the contamination studied here was due to spacecraft self-contamination enhanced by atomic oxygen plasma dynamics and solar UV radiation. These results also suggest the efficacy for the jet spray and ion beam contamination control technologies for spacecraft optical surfaces.

  11. Lead detoxification activities and ADMET hepatotoxicities of a class of novel 5-(1-carbonyl-L-amino-acid)-2,2-dimethyl-[1,3]dithiolane-4-carboxylic acids.

    PubMed

    Xu, Yanxia; Wang, Yuji; Zhao, Ming; Hou, Baoguang; Peng, Li; Zheng, Meiqing; Wu, Jianhui; Peng, Shiqi

    2011-03-15

    By linking the mercapto groups with isopropyl and introducing L-amino acid into the 5-carboxyl of DMSA a class of novel 5-(1-carbonyl-L-amino-acid)-2,2- dimethyl-[1,3]dithiolane-4-carboxylic acids were prepared. Their in vivo activities were evaluated on lead loaded mice at the dose of 0.4 mmol/kg. The results showed that the lead levels of the livers, kidneys, femurs and brains in particular could be efficiently decreased by 0.4 mmol/kg of 5-(1-carbonyl-L-amino-acid)-2,2-dimethyl-[1,3]dithiolane-4-carboxylic acids. The benefit of 5-(1-carbonyl-L-amino-acid)-2,2-dimethyl-[1,3]dithiolane-4-carboxylic acids to the detoxification of the brain lead was attributed to their transmembrane ability. Compared with the lead detoxification efficacy, they did not affect the essential metals such as Fe, Cu, Zn, and Ca of the treated mice. Silico molecular modeling predicted that 5-(1-carbonyl-L-amino-acid)-2,2-dimethyl-[1,3]dithiolane-4-carboxylic acids had no hepatotoxicity.

  12. Targeting multiple cannabinoid anti-tumour pathways with a resorcinol derivative leads to inhibition of advanced stages of breast cancer

    PubMed Central

    Murase, Ryuichi; Kawamura, Rumi; Singer, Eric; Pakdel, Arash; Sarma, Pranamee; Judkins, Jonathon; Elwakeel, Eiman; Dayal, Sonali; Martinez-Martinez, Esther; Amere, Mukkanti; Gujjar, Ramesh; Mahadevan, Anu; Desprez, Pierre-Yves; McAllister, Sean D

    2014-01-01

    Background and Purpose The psychoactive cannabinoid Δ9-tetrahydrocannabinol (THC) and the non-psychoactive cannabinoid cannabidiol (CBD) can both reduce cancer progression, each through distinct anti-tumour pathways. Our goal was to discover a compound that could efficiently target both cannabinoid anti-tumour pathways. Experimental Approach To measure breast cancer cell proliferation/viability and invasion, MTT and Boyden chamber assays were used. Modulation of reactive oxygen species (ROS) and apoptosis was measured using dichlorodihydrofluorescein and annexin/propidium iodide, respectively, in combination with cell flow cytometry. Changes in protein levels were evaluated using Western analysis. Orthotopic and i.v. mouse models of breast cancer metastasis were used to test the activity of cannabinoids in vivo. Key Results CBD reduced breast cancer metastasis in advanced stages of the disease as the direct result of down-regulating the transcriptional regulator Id1. However, this was associated with moderate increases in survival. We therefore screened for analogues that could co-target cannabinoid anti-tumour pathways (CBD- and THC-associated) and discovered the compound O-1663. This analogue inhibited Id1, produced a marked stimulation of ROS, up-regulated autophagy and induced apoptosis. Of all the compounds tested, it was the most potent at inhibiting breast cancer cell proliferation and invasion in culture and metastasis in vivo. Conclusions and Implications O-1663 prolonged survival in advanced stages of breast cancer metastasis. Developing compounds that can simultaneously target multiple cannabinoid anti-tumour pathways efficiently may provide a novel approach for the treatment of patients with metastatic breast cancer. PMID:24910342

  13. Mineralization of the recalcitrant oxalic and oxamic acids by electrochemical advanced oxidation processes using a boron-doped diamond anode.

    PubMed

    Garcia-Segura, Sergi; Brillas, Enric

    2011-04-01

    Oxalic and oxamic acids are the ultimate and more persistent by-products of the degradation of N-aromatics by electrochemical advanced oxidation processes (EAOPs). In this paper, the kinetics and oxidative paths of these acids have been studied for several EAOPs using a boron-doped diamond (BDD) anode and a stainless steel or an air-diffusion cathode. Anodic oxidation (AO-BDD) in the presence of Fe(2+) (AO-BDD-Fe(2+)) and under UVA irradiation (AO-BDD-Fe(2+)-UVA), along with electro-Fenton (EF-BDD), was tested. The oxidation of both acids and their iron complexes on BDD was clarified by cyclic voltammetry. AO-BDD allowed the overall mineralization of oxalic acid, but oxamic acid was removed much more slowly. Each acid underwent a similar decay in AO-BDD-Fe(2+) and EF-BDD, as expected if its iron complexes were not attacked by hydroxyl radicals in the bulk. The faster and total mineralization of both acids was achieved in AO-BDD-Fe(2+)-UVA due to the high photoactivity of their Fe(III) complexes that were continuously regenerated by oxidation of their Fe(II) complexes. Oxamic acid always released a larger proportion of NH(4)(+) than NO(3)(-) ion, as well as volatile NO(x) species. Both acids were independently oxidized at the anode in AO-BDD, but in AO-BDD-Fe(2+)-UVA oxamic acid was more slowly degraded as its content decreased, without significant effect on oxalic acid decay. The increase in current density enhanced the oxidation power of the latter method, with loss of efficiency. High Fe(2+) contents inhibited the oxidation of Fe(II) complexes by the competitive oxidation of Fe(2+) to Fe(3+). Low current densities and Fe(2+) contents are preferable to remove more efficiently these acids by the most potent AO-BDD-Fe(2+)-UVA method.

  14. Accuracy of advanced versus strictly conventional 12-lead ECG for detection and screening of coronary artery disease, left ventricular hypertrophy and left ventricular systolic dysfunction

    PubMed Central

    2010-01-01

    Background Resting conventional 12-lead ECG has low sensitivity for detection of coronary artery disease (CAD) and left ventricular hypertrophy (LVH) and low positive predictive value (PPV) for prediction of left ventricular systolic dysfunction (LVSD). We hypothesized that a ~5-min resting 12-lead advanced ECG test ("A-ECG") that combined results from both the advanced and conventional ECG could more accurately screen for these conditions than strictly conventional ECG. Methods Results from nearly every conventional and advanced resting ECG parameter known from the literature to have diagnostic or predictive value were first retrospectively evaluated in 418 healthy controls and 290 patients with imaging-proven CAD, LVH and/or LVSD. Each ECG parameter was examined for potential inclusion within multi-parameter A-ECG scores derived from multivariate regression models that were designed to optimally screen for disease in general or LVSD in particular. The performance of the best retrospectively-validated A-ECG scores was then compared against that of optimized pooled criteria from the strictly conventional ECG in a test set of 315 additional individuals. Results Compared to optimized pooled criteria from the strictly conventional ECG, a 7-parameter A-ECG score validated in the training set increased the sensitivity of resting ECG for identifying disease in the test set from 78% (72-84%) to 92% (88-96%) (P < 0.0001) while also increasing specificity from 85% (77-91%) to 94% (88-98%) (P < 0.05). In diseased patients, another 5-parameter A-ECG score increased the PPV of ECG for LVSD from 53% (41-65%) to 92% (78-98%) (P < 0.0001) without compromising related negative predictive value. Conclusion Resting 12-lead A-ECG scoring is more accurate than strictly conventional ECG in screening for CAD, LVH and LVSD. PMID:20565702

  15. Research, development, and demonstration of lead-acid batteries for electric-vehicle propulsion. Annual report, 1980

    SciTech Connect

    Not Available

    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.

  16. Presence of dopa and amino acid hydroperoxides in proteins modified with advanced glycation end products (AGEs): amino acid oxidation products as a possible source of oxidative stress induced by AGE proteins.

    PubMed Central

    Fu, S; Fu, M X; Baynes, J W; Thorpe, S R; Dean, R T

    1998-01-01

    Glycation and subsequent Maillard or browning reactions of glycated proteins, leading to the formation of advanced glycation end products (AGEs), are involved in the chemical modification of proteins during normal aging and have been implicated in the pathogenesis of diabetic complications. Oxidative conditions accelerate the browning of proteins by glucose, and AGE proteins also induce oxidative stress responses in cells bearing AGE receptors. These observations have led to the hypothesis that glycation-induced pathology results from a cycle of oxidative stress, increased chemical modification of proteins via the Maillard reaction, and further AGE-dependent oxidative stress. Here we show that the preparation of AGE-collagen by incubation with glucose under oxidative conditions in vitro leads not only to glycation and formation of the glycoxidation product Nepsilon-(carboxymethyl)lysine (CML), but also to the formation of amino acid oxidation products on protein, including m-tyrosine, dityrosine, dopa, and valine and leucine hydroperoxides. The formation of both CML and amino acid oxidation products was prevented by anaerobic, anti-oxidative conditions. Amino acid oxidation products were also formed when glycated collagen, prepared under anti-oxidative conditions, was allowed to incubate under aerobic conditions that led to the formation of CML. These experiments demonstrate that amino acid oxidation products are formed in proteins during glycoxidation reactions and suggest that reactive oxygen species formed by redox cycling of dopa or by the metal-catalysed decomposition of amino acid hydroperoxides, rather than by redox activity or reactive oxygen production by AGEs on protein, might contribute to the induction of oxidative stress by AGE proteins. PMID:9461515

  17. Associations of blood pressure and hypertension with lead dose measures and polymorphisms in the vitamin D receptor and delta-aminolevulinic acid dehydratase genes.

    PubMed Central

    Lee, B K; Lee, G S; Stewart, W F; Ahn, K D; Simon, D; Kelsey, K T; Todd, A C; Schwartz, B S

    2001-01-01

    Evidence suggests that lead and selected genes known to modify the toxicokinetics of lead--namely, those for the vitamin D receptor (VDR) and delta-aminolevulinic acid dehydratase (ALAD)--may independently influence blood pressure and hypertension risk. We report the relations among ALAD and VDR genotypes, three lead dose measures, and blood pressure and hypertension status in 798 Korean lead workers and 135 controls without occupational exposure to lead. Lead dose was assessed by blood lead, tibia lead measured by X-ray fluorescence, and dimercaptosuccinic acid (DMSA)-chelatable lead. Among lead workers, 9.9% (n = 79) were heterozygous for the ALAD(2) allele, and there were no ALAD(2) homozygotes; 11.2% (n = 89) had at least one copy of the VDR B allele, and 0.5% (n = 4) had the BB genotype. In linear regression models to control for covariates, VDR genotype (BB and Bb vs. bb), blood lead, tibia lead, and DMSA-chelatable lead were all positive predictors of systolic blood pressure. On average, lead workers with the VDR B allele, mainly heterozygotes, had systolic blood pressures that were 2.7-3.7 mm Hg higher than did workers with the bb genotype. VDR genotype was also associated with diastolic blood pressure; on average, lead workers with the VDR B allele had diastolic blood pressures that were 1.9-2.5 mm Hg higher than did lead workers with the VDR bb genotype (p = 0.04). VDR genotype modified the relation of age with systolic blood pressure; compared to lead workers with the VDR bb genotype, workers with the VDR B allele had larger elevations in blood pressure with increasing age. Lead workers with the VDR B allele also had a higher prevalence of hypertension compared to lead workers with the bb genotype [adjusted odds ratio (95% confidence interval) = 2.1 (1.0, 4.4), p = 0.05]. None of the lead biomarkers was associated with diastolic blood pressure, and tibia lead was the only lead dose measure that was a significant predictor of hypertension status. In

  18. Effects of chebulic acid on advanced glycation endproducts-induced collagen cross-links.

    PubMed

    Lee, Ji-Young; Oh, Jun-Gu; Kim, Jin Sook; Lee, Kwang-Won

    2014-01-01

    Advanced glycation end-products (AGEs) have been implicated in the development of diabetic complications. We report the antiglycating activity of chebulic acid (CA), isolated from Terminalia chebula on breaking the cross-links of proteins induced by AGEs and inhibiting the formation of AGEs. Aminoguanidine (AG) reduced 50% of glycated bovine serum albumin (BSA) with glycolaldehyde (glycol-BSA)-induced cross-links of collagen at a concentration of 67.8 ± 2.5 mM, the level of CA required for exerting a similar antiglycating activity was 38.8 ± 0.5 µM. Also, the breaking activity on collagen cross-links induced by glycol-BSA was potent with CA (IC50=1.46 ± 0.05 mM), exhibiting 50-fold stronger breaking activity than with ALT-711, a well-known cross-link breaker (IC50=72.2 ± 2.4 mM). IC50 values of DPPH· scavenging activity for CA and ascorbic acid (AA) were 39.2 ± 4.9 and 19.0 ± 1.2 µg dry matter (DM) mL(-1), respectively, and ferric reducing and antioxidant power (FRAP) activities for CA and AA were 4.70 ± 0.06 and 11.4 ± 0.1 mmol/FeSO4·7H2O/g DM, respectively. The chelating activities of CA, AG and ALT711 on copper-catalyzed oxidation of AA were compared, and in increasing order, ALT-711 (IC50 of 1.92 ± 0.20 mM)

  19. Associations of patella lead with polymorphisms in the vitamin D receptor, delta-aminolevulinic acid dehydratase and endothelial nitric oxide synthase genes.

    PubMed

    Theppeang, Keson; Schwartz, Brian S; Lee, Byung-Kook; Lustberg, Mark E; Silbergeld, Ellen K; Kelsey, Karl T; Parsons, Patrick J; Todd, Andrew C

    2004-06-01

    A cross-sectional analysis was performed to evaluate associations of polymorphisms in the vitamin D receptor (VDR), delta-aminolevulinic acid dehydratase (ALAD), and endothelial nitric oxide synthase (eNOS) genes with patella lead concentrations in 652 lead workers in the Republic of Korea. There was a wide range of patella lead (from below detection limit to 946 microg Pb/g bone mineral), with a mean (standard deviation) of 75.2 (101.0). There were no associations of ALAD or eNOS genotypes with patella lead, but workers with the VDR B allele had significantly (P value < 0.05) higher patella lead (on average, 25% or approximately 6.6 microg Pb/g bone mineral) than lead workers with the VDR bb genotype. There was evidence that the relation between age and patella lead was modified by both the VDR and eNOS genotypes.

  20. Dust detector using piezoelectric lead zirconate titanate with current-to-voltage converting amplifier for functional advancement

    NASA Astrophysics Data System (ADS)

    Kobayashi, Masanori; Miyachi, Takashi; Hattori, Maki; Sugita, Seiji; Takechi, Seiji; Okada, Nagaya

    2013-03-01

    This paper describes the concept of a dust monitor using lead zirconate titanate (PZT) ceramics with a large detection area. Its potential as a dust detector is experimentally demonstrated. The dust monitor has a small volume compared to an impact ionization detector with the same detection area, due to the PZT sensor. The PZT sensor, as a traditional device for the in-situ observation of hypervelocity dust particles, has been used for momentum measurement. The hypervelocity impact signals of PZT sensors are typically read by charge-sensitive amplifiers. Instead, we suggest a new method that a current-to-voltage converting amplifier is useful for interpreting the impact signal of a PZT sensor arising from dust particles down to 0.5 μm in radius. We propose that datasets of dust impacts can be obtained with a higher statistical accuracy, if the new method is applied to instruments on forthcoming interplanetary-space-cruising spacecrafts.

  1. Advanced X-Ray Inspection of Reinforced Carbon Composite Materials on the Orbiter Leading Edge Structural Subsystem (LESS)

    NASA Technical Reports Server (NTRS)

    Hernandez, Jose M.; Berry, Robert F.; Osborn, Robin; Bueno, Clifford; Osterlitz, Mark; Mills, Richard; Morris, Philip; Phalen, Robert; McNab, Jim; Thibodeaux, Tahanie; Thompson, Kyle

    2004-01-01

    The post return-to-flight (RTF) inspection methodology for the Orbiter Leading Edge Structural Subsystem (LESS) is currently being defined. Numerous NDT modalities and techniques are being explored to perform the flight-to-flight inspections of the reinforced carbon/carbon (RCC) composite material for impact damage, general loss of mass in the bulk layers, or other anomalous conditions that would pose risk to safe return upon re-entry. It is possible to have an impact upon ascent that is not visually observable on the surface, yet causes internal damage. Radiographic testing may be a useful NDT technique for such occurrences. The authors have performed radiographic tests on full-sized mock samples of LESS hardware with embedded image quality phantoms. Digitized radiographic film, computed radiography and flat panel digital real-time radiography was acquired using a GE Eresco 200 x-ray tube, and Se-75 and Yb-169 radioisotopes.

  2. Characterization of lead (Ⅱ)-containing activated carbon and its excellent performance of extending lead-acid battery cycle life for high-rate partial-state-of-charge operation

    NASA Astrophysics Data System (ADS)

    Tong, Pengyang; Zhao, Ruirui; Zhang, Rongbo; Yi, Fenyun; Shi, Guang; Li, Aiju; Chen, Hongyu

    2015-07-01

    In this work, lead (Ⅱ)-containing activated carbon (Pb@C) is prepared as the additive of negative active mass (NAM), aiming to enhance the electrochemical characteristics of the lead-acid battery. The characters of the Pb@C materials and their electrochemical properties are characterized by XRD, SEM, back-scattering electron image (BESI) and electrochemical methods. The lead (Ⅱ) ions disperse well in the carbon bulk of the obtained Pb@C materials as observed, and these materials exhibit remarkable higher specific capacitance and higher hydrogen evolution over-potential compared with original carbons. Many 2 V lead-acid batteries are assembled manually in our lab, and then the batteries are disassembled after formation and high-rate-partial-state-of-charge (HRPSoC) cycling. Results manifest that the Pb@C additives exhibit high affinity to lead and act as a porous-skeleton in the formation process as well as under HRPSoC cycling conditions, leading to the small and fine formation of PbSO4 particles and accordingly higher active material utilization rate more than 50%, better cycling performance and charging acceptance. Besides, excellent cycle performances of these batteries have great relationship with the dazzling hydrogen evolution performance of Pb@C materials. A possible working mechanism is also proposed based on the testing data in this paper.

  3. Does acute lead (Pb) contamination influence membrane fatty acid composition and freeze tolerance in intertidal blue mussels in arctic Greenland?

    PubMed

    Thyrring, Jakob; Juhl, Bodil Klein; Holmstrup, Martin; Blicher, Martin E; Sejr, Mikael K

    2015-11-01

    In their natural habitats, organisms are exposed to multiple stressors. Heavy metal contamination stresses the cell membrane due to increased peroxidation of lipids. Likewise, sub-zero air temperatures potentially reduce membrane functionality in ectothermal animals. We tested if acute lead (Pb) exposure for 7 days would influence survival in intertidal blue mussels (Mytilus edulis) after exposure to realistic sub-zero air temperatures. A full factorial experiment with five tissue Pb concentrations between 0 and 3500 μg Pb/g and six sub-zero temperatures from 0 to -17 °C were used to test the hypothesis that sub-lethal effects of Pb may increase the lethality caused by freezing in blue mussels exposed to temperatures simulating Greenland winter conditions. We found a significant effect of temperature on mortality. However, the short-term exposure to Pb did not result in any effects of Pb, nor did we find interactions between Pb and temperature. We analysed the relative abundance of major phospholipid fatty acids (PLFAs) in the gill tissue, but we found no significant effect of Pb tissue concentration on PLFA composition. Results suggest that Pb accumulation has limited effects on freeze tolerance and does not induce membrane damage in terms of persistent lipid peroxidation.

  4. Interactions between lead-zirconate titanate, polyacrylic acid, and polyvinyl butyral in ethanol and their influence on electrophoretic deposition behavior.

    PubMed

    Kuscer, Danjela; Bakarič, Tina; Kozlevčar, Bojan; Kosec, Marija

    2013-02-14

    Electrophoretic deposition (EPD) is an attractive method for the fabrication of a few tens of micrometer-thick piezoelectric layers on complex-shape substrates that are used for manufacturing high-frequency transducers. Niobium-doped lead-zirconate titanate (PZT Nb) particles were stabilized in ethanol using poly(acrylic acid) (PAA). With Fourier-transform infrared spectroscopy (FT-IR), we found that the deprotonated carboxylic group from the PAA is coordinated with the metal in the perovskite PZT Nb structure, resulting in a stable ethanol-based suspension. The hydroxyl group from the polyvinyl butyral added into the suspension to prevent the formation of cracks in the as-deposited layer did not interact with the PAA-covered PZT Nb particles. PVB acts as a free polymer in ethanol-based suspensions. The electrophoretic deposition of micro- and nanometer-sized PZT Nb particles from ethanol-based suspensions onto electroded alumina substrates was attempted in order to obtain uniform, crack-free deposits. The interactions between the PZT Nb particles, the PAA, and the PVB in ethanol will be discussed and related to the properties of the suspensions, the deposition yield and the morphology of the as-deposited PZT Nb thick film.

  5. Citric acid improves lead (pb) phytoextraction in brassica napus L. by mitigating pb-induced morphological and biochemical damages.

    PubMed

    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.

  6. Modeling the impact of paste additives and pellet geometry on paste utilization within lead acid batteries during low rate discharges

    NASA Astrophysics Data System (ADS)

    Vargonen, Muhammed M.

    2015-01-01

    When designing a lead acid battery, there are many factors to consider in order to obtain the best compromise of cost, performance, and ease of manufacturability. We use a modeling approach to study some of the key factors which affect the amount of active material which can be utilized during a low rate discharge. We investigate the effects of pellet size, pellet geometry, disconnected grid mesh borders, and inert paste additives. Furthermore, we look at how the internal path length resistance within a pellet is dependent on those features. Our findings correlate well with earlier works, and help to explain some of the previously observed phenomenon. It is observed that utilization is indeed affected by pellet size, but small grid mesh sizes on the order of ∼4 mm edge lengths are necessary in order to realize a significant benefit. Utilization is presented as a function of pellet size, aspect ratio of the pellets, and the loading level of the inert additives in the pellets up to ten percent by volume.

  7. Effects of rest time on discharge response and equivalent circuit model for a lead-acid battery

    NASA Astrophysics Data System (ADS)

    Devarakonda, Lalitha; Hu, Tingshu

    2015-05-01

    This work carries out a detailed investigation on the effects of rest time on the discharge response and the parameters of the Thevenin's equivalent circuit model for a lead acid battery. Traditional methods for battery modeling require a long rest time before a discharging test so that a steady state is reached for the open circuit voltage. In a recent work, we developed an algebraic method for parameter identification of circuit models for batteries by applying discharging tests after variable and possibly very short rest time. This new method opens a door to the understanding of the effects of rest time on battery behavior, which may be used for better simulation, analysis and design of battery powered systems for improved battery efficiency and state of health. As we used the new method to extract circuit parameters after different rest times, we observed some unexpected results on the relationship between the rest time and circuit parameters. The initial voltages on the capacitors can be negative and becomes more negative as the rest time is increased. We also observed that the time constants increase with rest time. Relationships between rest time and other parameters are also reported in this paper.

  8. Determining soil enzyme activities for the assessment of fungi and citric acid-assisted phytoextraction under cadmium and lead contamination.

    PubMed

    Mao, Liang; Tang, Dong; Feng, Haiwei; Gao, Yang; Zhou, Pei; Xu, Lurong; Wang, Lumei

    2015-12-01

    Microorganism or chelate-assisted phytoextraction is an effective remediation tool for heavy metal polluted soil, but investigations into its impact on soil microbial activity are rarely reported. Consequently, cadmium (Cd)- and lead (Pb)-resistant fungi and citric acid (CA) were introduced to enhance phytoextraction by Solanum nigrum L. under varied Cd and Pb pollution levels in a greenhouse pot experiment. We then determined accumulation of Cd and Pb in S. nigrum and the soil enzyme activities of dehydrogenase, phosphatase, urease, catalase, sucrase, and amylase. Detrended canonical correspondence analysis (DCCA) was applied to assess the interactions between remediation strategies and soil enzyme activities. Results indicated that the addition of fungi, CA, or their combination enhanced the root biomass of S. nigrum, especially at the high-pollution level. The combined treatment of CA and fungi enhanced accumulation of Cd about 22-47 % and of Pb about 13-105 % in S. nigrum compared with the phytoextraction alone. However, S. nigrum was not shown to be a hyperaccumulator for Pb. Most enzyme activities were enhanced after remediation. The DCCA ordination graph showed increasing enzyme activity improvement by remediation in the order of phosphatase, amylase, catalase, dehydrogenase, and urease. Responses of soil enzyme activities were similar for both the addition of fungi and that of CA. In summary, results suggest that fungi and CA-assisted phytoextraction is a promising approach to restoring heavy metal polluted soil.

  9. Amplification of electrolyte uptake in the absorptive glass mat (AGM) separator for valve regulated lead acid (VRLA) batteries

    NASA Astrophysics Data System (ADS)

    Kumar, Vijay; Kameswara Rao, P. V.; Rawal, Amit

    2017-02-01

    Absorptive glass mat (AGM) separators are widely used for valve regulated lead acid (VRLA) batteries due to their remarkable fiber and structural characteristics. Discharge performance and recharge effectiveness of VRLA batteries essentially rely on the distribution and saturation levels of the electrolyte within the AGM separator. Herein, we report an analytical model for predicting the wicking characteristics of AGM battery separators under unconfined and confined states. The model of wicking behavior of AGM is based upon Fries and Dreyer's approach that included the effect of gravity component which was neglected in classic Lucas-Washburn's model. In addition, the predictive model of wicking accounted for realistic structural characteristics of AGM via orientation averaging approach. For wicking under confined state, the structural parameters have been updated under defined level of compressive stresses based upon the constitutive equation derived for a planar network of fibers in AGM under transverse loading conditions. A comparison has been made between the theoretical models and experimental results of wicking behavior under unconfined and confined states. Most importantly, the presented work has highlighted the questionable validity of classic Lucas-Washburn model for predicting the wicking characteristics of AGM separator over longer time duration.

  10. The effect of fulvic acids on the toxicity of lead and manganese to arbuscular mycorrhizal fungus Glomus intraradices.

    PubMed

    Malcová, R; Gryndler, M; Hrselová, H; Vosátka, M

    2002-01-01

    The effect of fulvic acids (FA) on arbuscular mycorrhizal (AM) fungi and on the toxicity of lead and manganese toward these symbionts were demonstrated in vitro. Incubation of root segments colonized with the AM fungus Glomus intraradices in undiluted fraction of FA (813 mg/L carbon) decreased an outgrowth of intraradical hyphae. Diluted FA solutions (< 271 mg/L C) did not influence the proportion of root segments bearing proliferating hyphae; solution containing 27.1 mg/L C even increased the proliferation. A decrease of heavy metal toxicity toward the fungus was observed when FA (81.3 mg/L C) were added to the solutions containing higher concentrations (< or = 100 mumol/L) of Mn and Pb; the positive effect of FA was not significant at higher concentrations of metals (0.5 mmol/L). A short-term cultivation of six different saprophytic microorganisms--three actinomycetes and three filamentous fungi--on the FA media (81.3 mg/L C) did not result in a modification of hyphal proliferation from the root segments subsequently incubated in these media.

  11. Advances and challenges in the treatment of branched-chain amino/keto acid metabolic defects

    PubMed Central

    Weinhold, Natalie; Vockley, Jerry; Gibson, K. Michael

    2014-01-01

    Summary Disorders of branched-chain amino/keto acid metabolism encompass diverse entities, including maple syrup urine disease (MSUD), the ‘classical’ organic acidurias isovaleric acidemia (IVA), propionic acidemia (PA), methylmalonic acidemia (MMA) and, among others, rarely described disorders such as 2-methylbutyryl-CoA dehydrogenase deficiency (MBDD) or isobutyryl-CoA dehydrogenase deficiency (IBDD). Our focus in this review is to highlight the biochemical basis underlying recent advances and ongoing challenges of long-term conservative therapy including precursor/protein restriction, replenishment of deficient substrates, and the use of antioxidants and anaplerotic agents which refill the Krebs cycle. Ongoing clinical assessments of affected individuals in conjunction with monitoring of disease-specific biochemical parameters remain essential. It is likely that mass spectrometry-based ‘metabolomics’ may be a helpful tool in the future for studying complete biochemical profiles and diverse metabolic phenotypes. Prospective studies are needed to test the effectiveness of adjunct therapies such as antioxidants, ornithine-alpha-ketoglutarate (OKG) or creatine in addition to specialized diets and to optimize current therapeutic strategies in affected individuals. With the individual lifetime risk and degree of severity being unknown in asymptomatic individuals with MBDD or IBDD, instructions regarding risks for metabolic stress and fasting avoidance along with clinical monitoring are reasonable interventions at the current time. Overall, it is apparent that carefully designed prospective clinical investigations and multicenter cohort-controlled trials are needed in order to leverage that knowledge into significant breakthroughs in treatment strategies and appropriate approaches. PMID:21290185

  12. Associations of renal function with polymorphisms in the delta-aminolevulinic acid dehydratase, vitamin D receptor, and nitric oxide synthase genes in Korean lead workers.

    PubMed

    Weaver, Virginia M; Schwartz, Brian S; Ahn, Kyu-Dong; Stewart, Walter F; Kelsey, Karl T; Todd, Andrew C; Wen, Jiayu; Simon, David J; Lustberg, Mark E; Parsons, Patrick J; Silbergeld, Ellen K; Lee, Byung-Kook

    2003-10-01

    We analyzed data from 798 lead workers to determine whether polymorphisms in the genes encoding delta-aminolevulinic acid dehydratase (ALAD), endothelial nitric oxide synthase (eNOS), and the vitamin D receptor (VDR) were associated with or modified relations of lead exposure and dose measures with renal outcomes. Lead exposure was assessed with job duration, blood lead, dimercaptosuccinic acid (DMSA)-chelatable lead, and tibia lead. Renal function was assessed with blood urea nitrogen (BUN), serum creatinine, measured creatinine clearance, calculated creatinine clearance and urinary N-acetyl-beta-D-glucosaminidase (NAG), and retinol-binding protein. Mean (+/- SD) tibia lead, blood lead, and DMSA-chelatable lead levels were 37.2 +/- 40.4 microg/g bone mineral, 32.0 +/- 15.0 microg/dL, and 767.8 +/- 862.1 microg/g creatinine, respectively. After adjustment, participants with the ALAD(2) allele had lower mean serum creatinine and higher calculated creatinine clearance. We observed effect modification by ALAD on associations between blood lead and/or DMSA-chelatable lead and three renal outcomes. Among those with the ALAD(1-2) genotype, higher lead measures were associated with lower BUN and serum creatinine and higher calculated creatinine clearance. Participants with the eNOS variant allele were found to have higher measured creatinine clearance and BUN. In participants with the Asp allele, longer duration working with lead was associated with higher serum creatinine and lower calculated creatinine clearance and NAG; all were significantly different from relations in those with the Glu/Glu genotype except NAG (p = 0.08). No significant differences were seen in renal outcomes by VDR genotype, nor was consistent effect modification observed. The ALAD findings could be explained by lead-induced hyperfiltration.

  13. Benchmarking of thermal hydraulic loop models for Lead-Alloy Cooled Advanced Nuclear Energy System (LACANES), phase-I: Isothermal steady state forced convection

    NASA Astrophysics Data System (ADS)

    Cho, Jae Hyun; Batta, A.; Casamassima, V.; Cheng, X.; Choi, Yong Joon; Hwang, Il Soon; Lim, Jun; Meloni, P.; Nitti, F. S.; Dedul, V.; Kuznetsov, V.; Komlev, O.; Jaeger, W.; Sedov, A.; Kim, Ji Hak; Puspitarini, D.

    2011-08-01

    As highly promising coolant for new generation nuclear reactors, liquid Lead-Bismuth Eutectic has been extensively worldwide investigated. With high expectation about this advanced coolant, a multi-national systematic study on LBE was proposed in 2007, which covers benchmarking of thermal hydraulic prediction models for Lead-Alloy Cooled Advanced Nuclear Energy System (LACANES). This international collaboration has been organized by OECD/NEA, and nine organizations - ENEA, ERSE, GIDROPRESS, IAEA, IPPE, KIT/IKET, KIT/INR, NUTRECK, and RRC KI - contribute their efforts to LACANES benchmarking. To produce experimental data for LACANES benchmarking, thermal-hydraulic tests were conducted by using a 12-m tall LBE integral test facility, named as Heavy Eutectic liquid metal loop for integral test of Operability and Safety of PEACER (HELIOS) which has been constructed in 2005 at the Seoul National University in the Republic of Korea. LACANES benchmark campaigns consist of a forced convection (phase-I) and a natural circulation (phase-II). In the forced convection case, the predictions of pressure losses based on handbook correlations and that obtained by Computational Fluid Dynamics code simulation were compared with the measured data for various components of the HELIOS test facility. Based on comparative analyses of the predictions and the measured data, recommendations for the prediction methods of a pressure loss in LACANES were obtained. In this paper, results for the forced convection case (phase-I) of LACANES benchmarking are described.

  14. The Repurposing of Old Drugs or Unsuccessful Lead Compounds by in Silico Approaches: New Advances and Perspectives.

    PubMed

    Martorana, Annamaria; Perricone, Ugo; Lauria, Antonino

    2016-01-01

    Have you a compound in your lab, which was not successful against the designed target, or a drug that is no more attractive? The drug repurposing represents the right way to reconsider them. It can be defined as the modern and rationale approach of the traditional methods adopted in drug discovery, based on the knowledge, insight and luck, alias known as serendipity. This repurposing approach can be applied both in silico and in wet. In this review we report the molecular modeling facilities that can be of huge support in the repurposing of drugs and/or unsuccessful lead compounds. In the last decades, different methods were proposed to help the scientists in drug design and in drug repurposing. The steps strongly depend on the approach applied. It could be a ligand or a structure based method, correlated to the use of specific means. These processes, starting from a compound with potential therapeutic properties and a sizeable number of toxicity passed tests, can successfully speed up the very slow development of a molecule from bench to market. Herein, we discuss the facilities available to date, classifying them by methods and types. We have reported a series of databases, ligand and structure stand-alone software, and of web-based tools, which are free accessible to scientific community. This review does not claim to be exhaustive, but can be of interest to help in drug repurposing through in silico methods, as a valuable tool for the medicinal chemistry community.

  15. Determination of metal impurities in advanced lead zirconate titanate ceramics by axial view mode inductively coupled plasma optical emission spectrometry.

    PubMed

    Villanueva Tagle, M E; Larrea Marín, M T; Martin Gavilán, O; Durruthy Rodríguez, M D; Calderón Piñar, F; Pomares Alfonso, M S

    2012-05-30

    An inductively coupled plasma optical emission spectrometry quantification method for the determination of Al, Ca, Cr Cu, Fe, Mn, Mg, Ni, Zn, Ba, K, In and Co in lead zirconate-titanate (PZT) ceramics, modified with strontium and chromium, was developed. Total digestion of ceramics was achieved with a HNO(3), H(2)O(2) and HF (ac) mixture by using a microwave furnace. The sensitivity of the net signal intensity respect to radiofrequency power (P) and nebulizer argon flow (F(N)) variations was strongly dependent of the total excitation energy of line (TEE). For lines with TEE near metastable atoms and ions of argon, an increment of the sensitivities to P and F(N) variation was observed. At robust plasma conditions the matrix effect was reduced for all matrices and analytes considered. The precision of analysis ranged from 3 to 13%, whereas the analytes recoveries in the spiked samples varied, mostly, from 90 to 110%. The detection limits of studied elements were from 0.004 to 10 mg kg(-1).

  16. NASA's Advancements in Space-Based Spectrometry Lead to Improvements in Weather Prediction and Understanding of Climate Processes

    NASA Technical Reports Server (NTRS)

    Susskind, Joel; Iredell, Lena

    2010-01-01

    AIRS (Atmospheric Infra-Red Sounder), was launched, in conjunction with AMSU-A (Advanced Microwave Sounding Unit-A) on the NASA polar orbiting research satellite EOS (Earth Observing System) Aqua satellite in May 2002 as a next generation atmospheric sounding system. Atmospheric sounders provide information primarily about the vertical distribution of atmospheric temperature and water vapor distribution. This is achieved by measuring outgoing radiation in discrete channels (spectral intervals) which are sensitive primarily to variations of these geophysical parameters. The primary objectives of AIRS/AMSU were to utilize such information in order to improve the skill of numerical weather prediction as well as to measure climate variability and trends. AIRS is a multi-detector array grating spectrometer with 2378 channels covering the spectral range 650/cm (15 microns) to 2660/cm (3.6 microns) with a resolving power (i/a i) of roughly 1200 where a i is the spectral channel bandpass. Atmospheric temperature profile can be determined from channel observations taken within the 15 micron (the long-wave CO2 absorption band) and within the 4.2 micron (the short-wave CO2 absorption band). Radiances in these (and all other) spectral intervals in the infrared are also sensitive to the presence of clouds in the instrument?s field of view (FOV), which are present about 95% of the time. AIRS was designed so as to allow for the ability to produce accurate Quality Controlled atmospheric soundings under most cloud conditions. This was achieved by having 1) extremely low channel noise values in the shortwave portion of the spectrum and 2) a very flat spatial response function within a channel?s FOV. IASI, the high spectral resolution IR interferometer flying on the European METOP satellite, does not contain either of these important characteristics. The AIRS instrument was also designed to be extremely stabile with regard to its spectral radiometric characteristics, which is

  17. Elevated urinary excretion of beta-aminoisobutyric acid and delta-aminolevulinic acid (ALA) and the inhibition of ALA-synthase and ALA-dehydratase activities in both liver and kidney in mice exposed to lead.

    PubMed

    Tomokuni, K; Ichiba, M; Hirai, Y

    1991-12-01

    Urinary excretion of beta-aminoisobutyric acid (ABA) and delta-aminolevulinic acid (ALA) was investigated in mice exposed to lead (500 p.p.m.) in drinking water for 14 days. Concentrations of both urinary ABA and urinary ALA increased significantly in the lead-exposed mice. However, the degree of increasing excretion was higher in urinary ALA (10-fold of the control) than in urinary ABA (2-fold of the control). On the other hand, it was demonstrated that ALA dehydratase in liver and kidney is inhibited by exposure to lead, while ALA synthase in these tissues has no inhibitory effect.

  18. Advances in research on cis-9, trans-11 conjugated linoleic acid: a major functional conjugated linoleic acid isomer.

    PubMed

    Wang, Tao; Lee, Hong Gu

    2015-01-01

    Conjugated linoleic acid (CLA) consists of a group of positional and geometric conjugated isomers of linoleic acid. Since the identification of CLA as a factor that can inhibit mutagenesis and carcinogenesis, thousands of studies have been conducted in the last several decades. Among the many isomers discovered, cis-9, trans-11 CLA is the most intensively studied because of its multiple, isomer-specific effects in humans and animals. This paper provides an overview of the available data on cis-9, trans-11 CLA, including its isomer-specific effects, biosynthesis, in vivo/in vitro research models, quantification, and the factors influencing its content in ruminant products.

  19. Inhibition of erythrocytes δ-aminolevulinic acid dehydratase (ALAD) activity in fish from waters affected by lead smelters

    USGS Publications Warehouse

    Schmitt, Christopher J.; Caldwell, Colleen A.; Olsen, Bill; Serdar, Dave; Coffey, Mike

    2002-01-01

    We assessed the effects on fish of lead (Pb) released to streamsby smelters located in Trail, BC (Canada), E. Helena, MT, Herculaneum, MO, and Glover, MO. Fish were collected by electrofishing from sites located downstream of smelters and from reference sites. Blood from each fish was analyzed for δ-aminolevulinic acid dehydratase (ALAD) activity and hemoglobin (Hb), and samples of blood, liver, or carcass were analyzed for Pb, zinc (Zn), or both. Fish collected downstreamof all four smelters sites had elevated Pb concentrations, decreased ALAD activity, or both relative to their respectivereference sites. At E. Helena, fish from the downstream site also had lower Hb concentrations than fish from upstream. Differences among taxa were also apparent. Consistent with previous studies, ALAD activity in catostomids (Pisces: Catostomidae-northern hog sucker,Hypentelium nigricans;river carpsucker, Carpiodes carpio; largescale sucker, Catostomus macrocheilus; and mountain sucker, C. platyrhynchus) seemed more sensitive to Pb-induced ALADinhibition than the salmonids (Pisces: Salmonidae-rainbow trout,Oncorhynchus mykiss; brook trout,Salvelinus fontinalis) or common carp (Cyprinus carpio). Some of these differences may have resulted from differential accumulation of Zn, which was not measured at all sites. We detected noALAD activity in channel catfish (Ictaluruspunctatus) from either site on the Mississippi River at Herculaneum, MO. Our findings confirmed that Pb is releasedto aquatic ecosystems by smelters and accumulated by fish, andwe documented potentially adverse effects of Pb in fish. We recommend that Zn be measured along with Pb when ALAD activityis used as a biomarker and the collection of at least 10 fish ofa species at each site to facilitate statistical analysis.

  20. Poly(lactic acid) nanoparticles of the lead anticancer ruthenium compound KP1019 and its surfactant-mediated activation.

    PubMed

    Fischer, Britta; Heffeter, Petra; Kryeziu, Kushtrim; Gille, Lars; Meier, Samuel M; Berger, Walter; Kowol, Christian R; Keppler, Bernhard K

    2014-01-21

    Nanoparticle formulations offer besides the advantage of passive drug targeting also the opportunity to increase the stability of drugs. KP1019 is a lead ruthenium(III) compound which has been successfully tested in a clinical phase I trial. However, it is characterized by low stability in aqueous solution especially at physiological pH. To overcome this limitation, poly(lactic acid) (PLA) nanoparticles of KP1019 with two different surfactants (Pluronic F68 and Tween 80) were prepared by a single oil-in-water (o/w) emulsion. Cytotoxicity measurements comparing different aged Tween 80 nanoparticles revealed that the color change from brown to green was associated with an up to 20 fold increased activity compared to "free" KP1019. Further investigations suggested that this is based on the formation of enhanced intracellular reactive oxygen species levels. Additional studies revealed that the origin of the green color is a reaction between KP1019 and Tween 80. Kinetic studies of this reaction mixture using UV-Vis, ESI-MS and ESR spectroscopy indicated on the one hand a coordination of Tween 80 to KP1019, and on the other hand, the color change was found to correlate with a reduction of the Ru(III) center by the surfactant. Together, the results provide a first experimental approach to stabilize a biologically active Ru(II) species of KP1019 in aqueous solution, which probably can be also used to selectively generate this activated species in the tumor tissue via delivery of KP1019 using Tween 80 nanoparticles.

  1. Mechanisms leading to oligomers and SOA through aqueous photooxidation: insights from OH radical oxidation of acetic acid and methylglyoxal

    NASA Astrophysics Data System (ADS)

    Tan, Y.; Lim, Y. B.; Altieri, K. E.; Seitzinger, S. P.; Turpin, B. J.

    2012-01-01

    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.

  2. Experimental investigation of influence of acid rain on leaching and hydraulic characteristics of cement-based solidified/stabilized lead contaminated clay.

    PubMed

    Du, Yan-Jun; Jiang, Ning-Jun; Shen, Shui-Long; Jin, Fei

    2012-07-30

    Remediation of contaminated lands in China urban areas is of great concern. Degradation of construction facilities caused by acid rain is a serious environmental pollution issue in China. This paper presents an investigation of the effects of acid rain on leaching and hydraulic properties of cement-based solidified/stabilized lead contaminated soil. Laboratory tests including infiltration test and soaking test are conducted. It is found that the soil hydraulic conductivity decreases with increase in the pore volume of flow of permeant liquids (acid rain and distilled water). The decreasing rate in the case of the acid rain is lower than that in the case of the distilled water. The soaking test results show that pH and the presence of sulfate ions of acid rain have considerable influence on the leached concentrations and leaching rate of calcium.

  3. Influence of humic acid on the toxicity of copper, cadmium and lead to the unicellular alga, Synechosystis aquatilis

    SciTech Connect

    Shanmukhappa, H.; Neelakantan, K. )

    1990-06-01

    Humic acids are known to play a significant role in phytoplankton productivity by regulating the trace metals required for plant growth. Although few attempts have been made to evaluate the influence of humic acids on heavy metal toxicity to aquatic organisms, their interaction in natural waters is well documented. The present study was undertaken to evaluate the influence of humic acids (HA) extracted from mangrove sediments on Cu, Cd and Pb toxicity to the unicellular alga, Synechosystis aquatilis.

  4. Enhanced performance of starter lighting ignition type lead-acid batteries with carbon nanotubes as an additive to the active mass

    NASA Astrophysics Data System (ADS)

    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.

  5. Simultaneous voltammetric determination of paracetamol and ascorbic acid using a boron-doped diamond electrode modified with Nafion and lead films.

    PubMed

    Tyszczuk-Rotko, Katarzyna; Bęczkowska, Ilona; Wójciak-Kosior, Magdalena; Sowa, Ireneusz

    2014-11-01

    The paper describes the fabrication and application of a novel sensor (a boron-doped diamond electrode modified with Nafion and lead films) for the simultaneous determination of paracetamol and ascorbic acid by differential pulse voltammetry. The main advantage of the lead film and polymer covered boron-doped diamond electrode is that the sensitivity of the stripping responses is increased and the separation of paracetamol and ascorbic acid signals is improved due to the modification of the boron-doped diamond surface by the lead layer. Additionally, the repeatability of paracetamol and ascorbic acid signals is improved by the application of the Nafion film coating. In the presence of oxygen, linear calibration curves were obtained in a wide concentration range from 5×10(-7) to 2×10(-4) mol L(-1) for paracetamol and from 1×10(-6) to 5×10(-4) mol L(-1) for ascorbic acid. The analytical utility of the differential pulse voltammetric method elaborated was tested in the assay of paracetamol and ascorbic acid in commercially available pharmaceutical formulations and the method was validated by high performance liquid chromatography coupled with diode array detector.

  6. Protective Role of Omega-3 Polyunsaturated Fatty Acid against Lead Acetate-Induced Toxicity in Liver and Kidney of Female Rats

    PubMed Central

    Abdou, Heba M.; Hassan, Mohamed A.

    2014-01-01

    The present study was conducted to investigate the protective role of Omega-3 polyunsaturated fatty acids against lead acetate-induced toxicity in liver and kidney of female rats. Animals were divided into four equal groups; group 1 served as control while groups 2 and 3 were treated orally with Omega-3 fatty acids at doses of 125 and 260 mg/kg body weight, respectively, for 10 days. These groups were also injected with lead acetate (25 mg/kg body weight) during the last 5 days. Group 4 was treated only with lead acetate for 5 days and served as positive control group. Lead acetate increased oxidative stress through an elevation in MDA associated with depletion in antioxidant enzymes activities in the tissues. Moreover, the elevation of serum enzymes activities (ALT, AST, ALP, and LDH) and the levels of urea and creatinine were estimated but total proteins were decreased. Also, lead acetate-treatment induced hyperlipidemia via increasing of lipid profiles associated with decline in HDL-c level. Significant changes of Hb, PCV, RBCs, PLT, and WBCs in group 4 were recorded. The biochemical alterations of lead acetate were confirmed by histopathological changes and DNA damage. The administration of Omega-3 provided significant protection against lead acetate toxicity. PMID:25045676

  7. Fatty Acids in Membranes as Homeostatic, Metabolic and Nutritional Biomarkers: Recent Advancements in Analytics and Diagnostics

    PubMed Central

    Ferreri, Carla; Masi, Annalisa; Sansone, Anna; Giacometti, Giorgia; Larocca, Anna Vita; Menounou, Georgia; Scanferlato, Roberta; Tortorella, Silvia; Rota, Domenico; Conti, Marco; Deplano, Simone; Louka, Maria; Maranini, Anna Rosaria; Salati, Arianna; Sunda, Valentina; Chatgilialoglu, Chryssostomos

    2016-01-01

    Fatty acids, as structural components of membranes and inflammation/anti-inflammatory mediators, have well-known protective and regulatory effects. They are studied as biomarkers of pathological conditions, as well as saturated and unsaturated hydrophobic moieties in membrane phospholipids that contribute to homeostasis and physiological functions. Lifestyle, nutrition, metabolism and stress—with an excess of radical and oxidative processes—cause fatty acid changes that are examined in the human body using blood lipids. Fatty acid-based membrane lipidomics represents a powerful diagnostic tool for assessing the quantity and quality of fatty acid constituents and also for the follow-up of the membrane fatty acid remodeling that is associated with different physiological and pathological conditions. This review focuses on fatty acid biomarkers with two examples of recent lipidomic research and health applications: (i) monounsaturated fatty acids and the analytical challenge offered by hexadecenoic fatty acids (C16:1); and (ii) the cohort of 10 fatty acids in phospholipids of red blood cell membranes and its connections to metabolic and nutritional status in healthy and diseased subjects. PMID:28025506

  8. [Advanced biofuel-oriented engineering of fatty acid pathway: a review].

    PubMed

    Zhou, Yongjin J; Zhao, Zongbao K

    2011-09-01

    Biofuel is in high demand as an alternative energy source for petroleum and diesel. Fatty acid-based biofuel has higher energy density and better compatibility with existing infrastructures. Microbial fatty acid biosynthetic pathway is important to develop biofuel. In this article, recent progresses on the modification and reconstruction of fatty acid metabolism for the production of biofuel were reviewed, with a focus on micro-diesel, long chain fatty alcohol and alkane. Problems, solutions and directions for further development of fatty acid-based biofuel were also discussed in the respect of synthetic biology.

  9. [Advances in functional genomics studies underlying acetic acid tolerance of Saccharomyces cerevisiae].

    PubMed

    Zhao, Xinqing; Zhang, Mingming; Xu, Guihong; Xu, Jianren; Bai, Fengwu

    2014-03-01

    Industrial microorganisms are subject to various stress conditions, including products and substrates inhibitions. Therefore, improvement of stress tolerance is of great importance for industrial microbial production. Acetic acid is one of the major inhibitors in the cellulosic hydrolysates, which affects seriously on cell growth and metabolism of Saccharomyces cerevisiae. Studies on the molecular mechanisms underlying adaptive response and tolerance of acetic acid of S. cerevisiae benefit breeding of robust strains of industrial yeast for more efficient production. In recent years, more insights into the molecular mechanisms underlying acetic acid tolerance have been revealed through analysis of global gene expression and metabolomics analysis, as well as phenomics analysis by single gene deletion libraries. Novel genes related to response to acetic acid and improvement of acetic acid tolerance have been identified, and novel strains with improved acetic acid tolerance were constructed by modifying key genes. Metal ions including potassium and zinc play important roles in acetic acid tolerance in S. cerevisiae, and the effect of zinc was first discovered in our previous studies on flocculating yeast. Genes involved in cell wall remodeling, membrane transport, energy metabolism, amino acid biosynthesis and transport, as well as global transcription regulation were discussed. Exploration and modification of the molecular mechanisms of yeast acetic acid tolerance will be done further on levels such as post-translational modifications and synthetic biology and engineering; and the knowledge obtained will pave the way for breeding robust strains for more efficient bioconversion of cellulosic materials to produce biofuels and bio-based chemicals.

  10. Extending cycle life of lead-acid batteries: a new separation system allows the application of pressure on the plate group

    NASA Astrophysics Data System (ADS)

    Perrin, M.; Döring, H.; Ihmels, K.; Weiss, A.; Vogel, E.; Wagner, R.

    Since 1983, it has been claimed that pressure applied on a lead-acid battery increases its cycle life. But until now, the use of pressure in production batteries was limited by the mechanical properties of the conventional separation systems (absorptive glass mat (AGM), and gel) which cannot withstand mechanical pressure. In 1997, Daramic developed the new acid jellying separator (AJS) with the aim of combining the advantages of both conventional separation systems and to allow the application of lasting plate group pressure. The new separation system was evaluated and much information was gained on the effect of pressure in a lead-acid battery, e.g. on the evolution of the mechanical pressure during one cycle and during cycle life.

  11. Re-engineering nalidixic acid's chemical scaffold: A step towards the development of novel anti-tubercular and anti-bacterial leads for resistant pathogens.

    PubMed

    Peraman, Ramalingam; Varma, Raghu Veer; Reddy, Y Padmanabha

    2015-10-01

    Occurrence of antibacterial and antimycobacterial resistance stimulated a thrust to discover new drugs for infectious diseases. Herein we report the work on re-engineering nalidixic acid's chemical scaffold for newer leads. Stepwise clubbing of quinoxaline, 1,2,4-triazole/1,3,4-oxadiazole with nalidixic acid yielded better compounds. Compounds were screened against ciprofloxacin resistant bacteria and Mycobacterium tuberculosis H37Rv species. Results were obtained as minimum inhibitory concentration, it was evident that molecule with quinoxaline linked azide as side chain served as antitubercular lead (<6.25 μg/ml) whilst molecule with oxadiazole or triazole linked quinoxaline side chain served as anti-bacterial lead. Few compounds were significantly active against Escherichia coli and Proteus vulgaris with MIC less than 0.06 μg/ml and relatively potent than ciprofloxacin. No true compound was potentially active against Salmonella species as compared to amoxicillin.

  12. Recent advances in the direct and indirect liquid chromatographic enantioseparation of amino acids and related compounds: a review.

    PubMed

    Ilisz, István; Aranyi, Anita; Pataj, Zoltán; Péter, Antal

    2012-10-01

    Amino acids are essential for life, and have many functions in metabolism. One particularly important function is to serve as the building blocks of peptides and proteins, giving rise to complex three dimensional structures through disulfide bonds or crosslinked amino acids. Peptides are frequently cyclic and contain protein as well as non-protein aminoacids in many instances. Since most of the proteinogenic α-amino acids contain a chiral carbon atom (with the exception of glycine), the stereoisomers of all these amino acids and the peptides in which they are to be found may possess differences in biological activity in living systems. The impetus for advances in chiral separation has been highest in the past decade and this still continues to be an area of high focus. The important analytical task of the separation of isomers is achieved mainly by chromatographic methods. This review surveys indirect and direct HPLC separations of biologically and pharmaceutically important enantiomers of amino acids and related compounds, with emphasis on the literature published from 2005.

  13. [Advances in studies of absorption and utilization of amino acids by plants: A review].

    PubMed

    Cao, Xiao-chuang; Wu, Liang-huan; Ma, Qing-xu; Jin, Qian-yu

    2015-03-01

    Plant can directly take up the intact amino acids, thus bypass the microbial mineralization of organic nitrogen. As an excellent carbon and nitrogen source, there exists competition for amino acid absorption between plant roots.and soil microorganisms. And the total flux of amino acids in soil may be enormous due to the extensive sources and short half-life. Studies on amino acid nitrogen nutritional contribution for plant by the technique of nitrogen isotopic tracer, has become a research topic in recent years ,which will help us better understand the principle of soil fertility. This paper summarized the recent researches on amino acid morphological characteristics in soil and its metabolic mechanism and nitrogen nutritional contribution for plant in different ecosystems, and discussed the present status and development trend of the amino acid circulation mechanism in the plant-soil-microorganism ecosystem and its bioavailability for plant. Finally, the topics of environmental regulating mechanism of amino acid bioavailability, amino acid carbon-nitrogen metabolism, and how to improve the field organic nitrogen management were all the core issues to be resolved.

  14. Effects of combined lipoic acid and pyridoxine on albuminuria, advanced glycation end-products, and blood pressure in diabetic nephropathy.

    PubMed

    Noori, Nazanin; Tabibi, Hadi; Hosseinpanah, Farhad; Hedayati, Mehdi; Nafar, Mohsen

    2013-01-01

    This study was designed to investigate the effects of combined administration of lipoic acid and pyridoxine on albuminuria, oxidative stress, blood pressure, serum advanced glycation end-products, nitric oxide (NO), and endothelin-1 in patients with diabetic nephropathy. Thirty-four patients were randomly assigned to either a supplement group or a placebo group. The patients in the supplement group received 800 mg lipoic acid and 80 mg pyridoxine daily for 12 weeks, whereas the placebo group received corresponding placebos. Urinary albumin, serum malondialdehyde (MDA), and systolic blood pressure decreased significantly in the supplement group compared to the placebo group (p < 0.05). Serum NO increased in the supplement group compared to the placebo group (p < 0.05). Serum pentosidine and carboxymethyl lysine decreased significantly in the supplement group at the end of week 12 compared to baseline (p < 0.05). No statistically significant differences were observed between the two groups in mean changes of serum endothelin-1, glucose, and diastolic blood pressure. The present study indicates that combined administration of lipoic acid and pyridoxine improves albuminuria in patients with diabetic nephropathy by reducing oxidative stress, advanced glycation end-products, and systolic blood pressure. The reduction in microalbuminuria may be of benefit in retarding the progression of diabetic nephropathy.

  15. Different low-molecular-mass organic acids specifically control leaching of arsenic and lead from contaminated soil.

    PubMed

    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.

  16. Different low-molecular-mass organic acids specifically control leaching of arsenic and lead from contaminated soil

    NASA Astrophysics Data System (ADS)

    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 12 h 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.

  17. Recent advances in the risk assessment of melamine and cyanuric acid in animal feed

    SciTech Connect

    Dorne, Jean Lou; Vandenbroeck, Marc; Mennes, Wim; Knutsen, Helle K.; Vernazza, Francesco; Edler, Lutz; Benford, Diane

    2013-08-01

    Melamine can be present at low levels in food and feed mostly from its legal use as a food contact material in laminates and plastics, as a trace contaminant in nitrogen supplements used in animal feeds, and as a metabolite of the pesticide cyromazine. The mechanism of toxicity of melamine involves dose-dependent formation of crystals with either endogenous uric acid or a structural analogue of melamine, cyanuric acid, in renal tubules resulting in potential acute kidney failure. Co-exposure to melamine and cyanuric acid in livestock, fish, pets and laboratory animals shows higher toxicity compared with melamine or cyanuric acid alone. Evidence for crystal formation between melamine and other structural analogs i.e. ammelide and ammeline is limited. Illegal pet food adulterations with melamine and cyanuric acid and adulteration of milk with melamine resulted in melamine–cyanuric acid crystals, kidney damage and deaths of cats and dogs and melamine–uric acid stones, hospitalisation and deaths of children in China respectively. Following these incidents, the tolerable daily intake for melamine was re-evaluated by the U.S. Food and Drug Administration, the World Health Organisation, and the Scientific Panel on Contaminants in the Food Chain of the European Food Safety Authority (EFSA). This review provides an overview of toxicology, the adulteration incidents and risk assessments for melamine and its structural analogues. Particular focus is given to the recent EFSA risk assessment addressing impacts on animal and human health of background levels of melamine and structural analogues in animal feed. Recent research and future directions are discussed. - Highlights: ► Melamine in food and feed. ► Forms crystals in kidney with uric acid or cyanuric acid. ► Toxicity higher with cyanuric acid. ► Recent EFSA risk assessment. ► Animal and human health.

  18. Ilex paraguariensis and its main component chlorogenic acid inhibit fructose formation of advanced glycation endproducts with amino acids at conditions compatible with those in the digestive system.

    PubMed

    Bains, Yasmin; Gugliucci, Alejandro

    2017-03-01

    We have previously shown that Ilex paraguariensis extracts have potent antiglycation actions. Associations of excess free fructose consumption with inflammatory diseases have been proposed to be mediated through in situ enteral formation of fructose AGEs, which, after being absorbed may contribute to inflammatory diseases via engagement of RAGE. In this proof of principle investigation we show fluorescent AGE formation between amino acids (Arg, Lys, Gly at 10-50mM) and fructose (10-50mM) under time, temperature, pH and concentrations compatible with the digestive system lumen and its inhibition by Ilex paraguariensis extracts. Incubation of amino acids with fructose (but not glucose) leads to a time dependent formation of AGE fluorescence, already apparent after just 1h incubation, a time frame well compatible with the digestive process. Ilex paraguariensis (mate tea) inhibited AGE formation by 83% at 50μl/ml (p<0.001). Its main phenolics, caffeic acid and cholorogenic acid were as potent as aminoguanidine-a specific antiglycation agent: IC50 of 0.9mM (p<0.001). Our results suggest that AGE adducts form between fructose and amino acids at times and concentrations plausibly found in the intestines. The reaction is inhibited by mate tea and its individual phenolics (caffeic acid and chlorogenic acids). The study provides the first evidence for the proposed mechanism to explain epidemiological correlations between excess fructose consumption and inflammatory diseases. Enteral fructose-AGE formation would be inhibited by co-intake of Ilex paraguariensis, and potentially other beverages, fruits and vegetables that contain comparable concentrations of phenolics as in IP (mate tea).

  19. Relation of fatty acid composition in lead-exposed mallards to fat mobilization, lipid peroxidation and alkaline phosphatase activity

    USGS Publications Warehouse

    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 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 three 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 increased triglycerides and 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.

  20. Recent advances in the synthesis and application of fluorescent α-amino acids.

    PubMed

    Harkiss, Alexander H; Sutherland, Andrew

    2016-09-26

    Fluorescence spectroscopy has become a powerful technique for probing a range of complex biological processes including enzyme mechanisms and protein-protein interactions. While the application of this technique uses a number of strategies, many of these rely on the use of fluorescent α-amino acids. This review highlights the recent synthetic methods developed for the incorporation of highly conjugated chromophores into the side-chain of α-amino acids and the application of these compounds as probes for imaging in medicine and biology. In particular, the design and synthesis of α-amino acids bearing coumarin, flavone and polyaromatic derived chromophores is described.

  1. Biomonitoring of lead-contaminated Missouri streams with an assay for erythrocyte δ-aminolevulinic acid dehydratase activity in fish blood

    USGS Publications Warehouse

    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.

  2. Behavior of lead in pristine and urbanized acid wetlands in the New Jersey pinelands with special reference to the role of Sphagnum moss

    SciTech Connect

    Vedagiri, U.K.

    1989-01-01

    The purpose of this study was to investigate the behavior of lead in naturally acidic Sphagnum moss-dominated wetlands of the New Jersey Pinelands and to compare it to the behavior of lead in similar wetlands which had been impacted by storm-water runoff. Data from the field showed that the runoff-impacted sites were characterized by elevated pH, elimination of Spaghnum ground cover, erosion of peat substrate and high lead accumulations, contributing to an effective but decreasing sink capacity. Laboratory experiments explored differences in fractionation, mobility and bioavailability of lead between the two systems. The low pH and high dissolved organic matter of the pristine waters led to higher solubilization and complexing of added lead compared to impacted waters. Lead added to runoff showed unexpectedly high solubility and lability, possibly due to low suspended solids. Lead added to runoff was also much more mobile vertically through peat columns than lead added to swampwater, possibly due to its high lability. The extremely high porosity of the peat substrate allows rapid vertical migration of solutes during events of sudden influx, such as storms. Sphagnum moss greatly decreased vertical transport by binding and flow retardation. The lead that is held in the moss layer was differentially available to different species. Red maple seedlings were better able to take up lead from the peat substrate in the absence of moss cover while cranberry plants showed the reverse pattern. This may be related to differences in rooting requirements and growth of the two species. Lead added in runoff was initially less available to the plants than in swampwater, but was ultimately taken up the red maple, which could tolerate conditions in the impacted substrates.

  3. Polymorphisms of delta-aminolevulinic acid dehydratase (ALAD) and peptide transporter 2 (PEPT2) genes in children with low-level lead exposure

    PubMed Central

    Sobin, Christina; Gutierrez, Marisela; Alterio, Heather

    2009-01-01

    Low-level lead exposure during early childhood has long been associated with altered neurocognitive development and diminished cognitive functions. Over nine thousand U.S. industrial facilities annually emit significant amounts of lead, creating exposure risk particularly for minority children. The mechanisms by which low-level lead exerts neurotoxic effects are poorly understood. Once absorbed, the only intervention is source removal, thus primary prevention is key. Genetic biomarkers could provide an efficient means of identifying children at greatest risk. Common functional variants of genes that alter lead's neurotoxic potential have been identified and include delta-aminolevulinic acid dehydratase (ALAD2) and peptide transporter 2 (PEPT2*2). These polymorphisms have not been examined previously in Hispanic minority samples, or with regard to lowest level lead exposure. In 116 children of Mexican-American/Hispanic descent residing in zip codes previously designated as “high risk” for lead exposure (mean age = 8.1, S.D. = 1.9), blood lead level was measured at three time points over a 3-month period and averaged. DNA extraction was completed using buccal swab samples. The frequencies of the ALAD2 and PEPT2*2 polymorphisms observed in this sample closely approximated those previously reported for Anglo, European and Asian samples. As compared to children heterozygous for the PEPT2*2 polymorphism, and without the PEPT2*2 polymorphism, the geometric mean blood lead level of children homozygous for the PEPT2*2 polymorphism was significantly higher. In contrast to past studies, mean blood lead level of children heterozygous and homozygous for the ALAD2 polymorphism in this sample did not differ from that of children without the ALAD2 polymorphism. Higher blood lead burden in children with the PEPT2*2 mutation may suggest that this common genetic variant is a biomarker of increased vulnerability to the neurotoxic effects of lowest level lead exposure. PMID

  4. Effects of lead shot ingestion on delta-aminolevulinic acid dehydratase activity, hemoglobin concentration, and serum chemistry in bald eagles

    USGS Publications Warehouse

    Hoffman, D.J.; Pattee, O.H.; Wiemeyer, Stanley N.; Mulhern, B.

    1981-01-01

    Lead shot ingestion by bald eagles (Haliaeetus leucocephalus) is considered to be widespread and has been implicated in the death of eagles in nature. It was recently demonstrated under experimental conditions that ingestion of as few as 10 lead shot resulted in death within 12 to 20 days. In the present study hematological responses to lead toxicity including red blood cell ALAD activity, hemoglobin concentration and 23 different blood serum chemistries were examined in five captive bald eagles that were unsuitable for rehabilitation and release. Eagles were dosed by force-feeding with 10 lead shot; they were redosed if regurgitation occurred. Red blood cell ALAD activity was inhibited by nearly 80% within 24 hours when mean blood lead concentration had increased to 0.8 parts per million (ppm). By the end of 1 week there was a significant decrease (20-25%) in hematocrit and hemoglobin, and the mean blood lead concentration was over 3 ppm. Within as little as 1-2 weeks after dosing, significant elevations in serum creatinine and serum alanine aminotransferase occurred, as well as a significant decrease in the ratio of serum aspartic aminotransferase to serum alanine aminotransferase. The mean blood lead concentration was over 5 ppm by the end of 2 weeks. These changes in serum chemistry may be indicative of kidney and liver alterations.

  5. Lead sulfate nano- and microparticles in the acid plant blow-down generated at the sulfuric acid plant of the El Teniente mine, Chile.

    PubMed

    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.

  6. Recent advances in understanding trans-epithelial acid-base regulation and excretion mechanisms in cephalopods

    PubMed Central

    Hu, Marian Y; Hwang, Pung-Pung; Tseng, Yung-Che

    2015-01-01

    Cephalopods have evolved complex sensory systems and an active lifestyle to compete with fish for similar resources in the marine environment. Their highly active lifestyle and their extensive protein metabolism has led to substantial acid-base regulatory abilities enabling these organisms to cope with CO2 induced acid-base disturbances. In convergence to teleost, cephalopods possess an ontogeny-dependent shift in ion-regulatory epithelia with epidermal ionocytes being the major site of embryonic acid-base regulation and ammonia excretion, while gill epithelia take these functions in adults. Although the basic morphology and excretory function of gill epithelia in cephalopods were outlined almost half a century ago, modern immunohistological and molecular techniques are bringing new insights to the mechanistic basis of acid-base regulation and excretion of nitrogenous waste products (e.g. NH3/NH4+) across ion regulatory epithelia of cephalopods. Using cephalopods as an invertebrate model, recent findings reveal partly conserved mechanisms but also novel aspects of acid-base regulation and nitrogen excretion in these exclusively marine animals. Comparative studies using a range of marine invertebrates will create a novel and exciting research direction addressing the evolution of pH regulatory and excretory systems. PMID:26716070

  7. Recent advances in understanding trans-epithelial acid-base regulation and excretion mechanisms in cephalopods.

    PubMed

    Hu, Marian Y; Hwang, Pung-Pung; Tseng, Yung-Che

    2015-01-01

    Cephalopods have evolved complex sensory systems and an active lifestyle to compete with fish for similar resources in the marine environment. Their highly active lifestyle and their extensive protein metabolism has led to substantial acid-base regulatory abilities enabling these organisms to cope with CO2 induced acid-base disturbances. In convergence to teleost, cephalopods possess an ontogeny-dependent shift in ion-regulatory epithelia with epidermal ionocytes being the major site of embryonic acid-base regulation and ammonia excretion, while gill epithelia take these functions in adults. Although the basic morphology and excretory function of gill epithelia in cephalopods were outlined almost half a century ago, modern immunohistological and molecular techniques are bringing new insights to the mechanistic basis of acid-base regulation and excretion of nitrogenous waste products (e.g. NH3/NH4 (+)) across ion regulatory epithelia of cephalopods. Using cephalopods as an invertebrate model, recent findings reveal partly conserved mechanisms but also novel aspects of acid-base regulation and nitrogen excretion in these exclusively marine animals. Comparative studies using a range of marine invertebrates will create a novel and exciting research direction addressing the evolution of pH regulatory and excretory systems.

  8. Determination of acid forming potential of massive sulfide minerals and the tailings situated in lead/zinc mining district of Balya (NW Turkey)

    NASA Astrophysics Data System (ADS)

    Çelebi, E. Ender; Öncel, M. Salim

    2016-12-01

    Weathering of sulfide minerals is a major source of acid production in nature and especially in mining territories. Pyrite is not the only principal mineral that generates acid drainage: other sulfide minerals (sphalerite, galena, chalcopyrite, etc.) may also be responsible for acid production. In addition to massive sulfide minerals, sulfide-bearing mine tailings may also produce acid drainage due to oxidation and hydrolysis reactions in waste dumps. The lead/zinc (Pb/Zn) mining region in Balya and Balıkesir, in Turkey, has operated mines intensively since the 1860s; so that characterization of the sulfide minerals and tailings situated and formed around the mining site is of great importance to secure a sustainable environment. For this purpose, acid production and neutralization potentials of massive sulfide ores of the region, and in the Pb/Zn process facility mine tailings from ten different points of tailings dam, have been determined by applied conventional Acid-Base Accounting (ABA) and Net Acid Generation (NAG) static tests after chemical and mineralogical analysis. The NAG pH and net acid production potential (NAPP) values were compared on a chart in order to classify the samples as either acid generating or non-acid generating. According to the comparisons, the sulfide minerals were classified as potentially acid forming (PAF). Massive pyrite had the highest NAPP and NAG pH value of 1966.6 kg H2SO4/ton and 1.91, respectively and the galena had the lowest NAPP value of 558.9 kg H2SO4/ton. However, the sphalerite NAG leachate pH value of 4.30 was the highest in sulfide minerals so that the sphalerite plotted near the uncertainty reference border in the PAF zone. In the mine tailings, NAPP values of 105.9 kg H2SO4/ton on average and the NAG pH values of over 7.5 were determined. In addition to these tests, water leaching (agitation test) was carried out on tailings in order to generate more information. The tailings did not generate acidic leachates as

  9. Cadmium, lead and zinc leaching from smelter fly ash in simple organic acids--simulators of rhizospheric soil solutions.

    PubMed

    Ettler, Vojtech; Vrtisková, Růzena; Mihaljevic, Martin; Sebek, Ondrej; Grygar, Tomás; Drahota, Petr

    2009-10-30

    Emissions from base-metal smelters are responsible for high contamination of the surrounding soils. Fly ash from a secondary Pb smelter was submitted to a batch leaching procedure (0.5-168 h) in 500 microM solutions of acetic, citric, or oxalic acids to simulate the release of toxic metals (Cd, Pb, Zn) in rhizosphere-like environments. Organic acids increased dissolution of fly ash by a factor of 1.3. Cadmium and Pb formed mobile chloro- and sulphate-complexes, whereas Zn partly present in a citrate (Zn-citrate(-)) complex is expected to be less mobile due to sorption onto the positively charged surfaces of hydrous ferric oxides (HFO) and organic matter (OM) in acidic soil.

  10. Gaston Planté and his invention of the lead-acid battery-The genesis of the first practical rechargeable battery

    NASA Astrophysics Data System (ADS)

    Kurzweil, P.

    In 1860, the Frenchman Gaston Planté (1834-1889) invented the first practical version of a rechargeable battery based on lead-acid chemistry-the most successful secondary battery of all ages. This article outlines Planté's fundamental concepts that were decisive for later development of practical lead-acid batteries. The 'pile secondaire' was indeed ahead its time in that an appropriate appliance for charging the accumulator was not available. The industrial success came after the invention of the Gramme machine. In 1879, Planté obtained acceptance for his work by publishing a book entitled Recherches sur l' Electricité. He never protected his inventions by patents, and spent much of his fortune on assisting impoverished scientists.

  11. Impedance measurements on lead-acid batteries for state-of-charge, state-of-health and cranking capability prognosis in electric and hybrid electric vehicles

    NASA Astrophysics Data System (ADS)

    Blanke, Holger; Bohlen, Oliver; Buller, Stephan; De Doncker, Rik W.; Fricke, Birger; Hammouche, Abderrezak; Linzen, Dirk; Thele, Marc; Sauer, Dirk Uwe

    Various attempts have been made to use impedance measurements for online analysis and offline modelling of lead-acid batteries. This presentation gives an overview on the latest and successful approaches based on impedance measurements to assess state-of-charge (SoC), state-of-health (SoH) and cranking capability of lead-acid batteries. Furthermore, it is shown that impedance data can serve as a basis for dynamic battery models for the simulation of vehicle power-supply systems. The methods and procedures aim for a reliable prediction of battery performance in electric vehicles, hybrid cars and classical automotive applications. Although, it will become obvious that impedance measurements give valuable information on the battery state, typically the information needs to be combined with other conventional algorithms or self-learning tools to achieve reliable and stable results for real-world applications.

  12. Kojic acid--a new leading molecule for a preparation of compounds with an anti-neoplastic potential.

    PubMed

    Novotný, L; Rauko, P; Abdel-Hamid, M; Váchalková, A

    1999-01-01

    Kojic acid as a molecule of natural origin may serve as template for the synthesis of new biologically active compounds. The synthetic KA (pyranone) derivatives possess various kinds of biological activities which are related by their similarity to flavonoids. The most important property is the antifungal and antineoplastic activity and capability of chelating metals. It is shown that the antineoplastic activity of kojic acid derivatives is based on various mechanisms of action on different levels of cellular metabolism and functions what makes this compound interesting for future investigation as cytotoxic agent.

  13. [Study advance on reproductive and developmental toxicity of haloacetic acids in drinking water].

    PubMed

    Xiang, Hong; Lu, Xiwu

    2008-03-01

    Haloacetic acids (HAAs) are major by-products of water disinfection of chlorination, Health effects on reproductive and developmental toxicities of haloacetic acids may be pay more attention to and may be interested in due to their high stability. In recent years numerous toxicological studies indicated that some HAAs could affect reproductive system and fertilizing capacity, inducing fetal anomaly and growth retardation in experimental animals. The recent studies on the reproductive and developmental effects of HAAs were discussed in this paper, the informations may be available for further study on reproductive and developmental effects of HAAs in drinking water.

  14. Mineralization of salicylic acid in acidic aqueous medium by electrochemical advanced oxidation processes using platinum and boron-doped diamond as anode and cathodically generated hydrogen peroxide.

    PubMed

    Guinea, Elena; Arias, Conchita; Cabot, Pere Lluís; Garrido, José Antonio; Rodríguez, Rosa María; Centellas, Francesc; Brillas, Enric

    2008-01-01

    Solutions containing 164 mg L(-1) salicylic acid of pH 3.0 have been degraded by electrochemical advanced oxidation processes such as anodic oxidation, anodic oxidation with electrogenerated H(2)O(2), electro-Fenton, photoelectro-Fenton and solar photoelectro-Fenton at constant current density. Their oxidation power has been comparatively studied in a one-compartment cell with a Pt or boron-doped diamond (BDD) anode and a graphite or O(2)-diffusion cathode. In the three latter procedures, 0.5mM Fe(2+) is added to the solution to form hydroxyl radical (()OH) from Fenton's reaction between Fe(2+) and H(2)O(2) generated at the O(2)-diffusion cathode. Total mineralization is attained for all methods with BDD and for photoelectro-Fenton and solar photoelectro-Fenton with Pt. The poor decontamination achieved in anodic oxidation and electro-Fenton with Pt is explained by the slow removal of most pollutants by ()OH formed from water oxidation at the Pt anode in comparison to their quick destruction with ()OH produced at BDD. ()OH generated from Fenton's reaction oxidizes rapidly all aromatic pollutants, but it cannot destroy final Fe(III)-oxalate complexes. Solar photoelectro-Fenton treatments always yield quicker degradation rate due to the very fast photodecarboxylation of these complexes by UVA irradiation supplied by solar light. The effect of current density on the degradation rate, efficiency and energy cost of all methods is examined. The salicylic acid decay always follows a pseudo-first-order kinetics. 2,3-Dihydroxybenzoic, 2,5-dihydroxybenzoic, 2,6-dihydroxybenzoic, alpha-ketoglutaric, glycolic, glyoxylic, maleic, fumaric, malic, tartronic and oxalic acids are detected as oxidation products. A general reaction sequence for salicylic acid mineralization considering all these intermediates is proposed.

  15. Modeling of the capacity loss of a 12 V automotive lead-acid battery due to ageing and comparison with measurement data

    NASA Astrophysics Data System (ADS)

    Kim, Ui Seong; Shin, Chee Burm; Chung, Seung Myun; Kim, Sung Tae; Cho, Byung Won

    One-dimensional modeling was carried-out to predict the capacity loss of a 12 V automotive lead-acid battery due to ageing. The model not only accounted for electrochemical kinetics and ionic mass transfer in a battery cell, but also considered the anodic corrosion of lead in sulfuric acid. In order to validate the modeling, modeling results were compared with the measurement data of the cycling behaviors of the lead-acid batteries having nominal capacity of 68 Ah that are mounted on the automobiles manufactured by Hyundai Motor Company. The cycling was performed under the protocol of the constant-current discharge and the constant-voltage charge. The discharge rate of C/3 was used. The range of state of charge was between 1 and 0.85. The voltage was kept constant at the gassing voltage until the charge current tapered to 10 mA. The retention capacity of the battery was measured with C/3 discharge rate before the beginning of cycling and after every 40 cycles of cycling. The modeling results were in good agreement with the measurement data.

  16. A Study on Electric Power Smoothing System for Lead-Acid Battery of Stand-Alone Natural Energy Power System Using EDLC

    NASA Astrophysics Data System (ADS)

    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.

  17. Consecutive visible-light photoredox decarboxylative couplings of adipic acid active esters with alkynyl sulfones leading to cyclic compounds.

    PubMed

    Li, Jingjing; Tian, Hua; Jiang, Min; Yang, Haijun; Zhao, Yufen; Fu, Hua

    2016-07-07

    Novel and efficient consecutive photoredox decarboxylative couplings of adipic acid active esters (bis(1,3-dioxoisoindolin-2-yl)-substituted hexanedioates) with substituted 1-(2-arylethynylsulfonyl)benzenes have been developed under visible-light photocatalysis. The successive photoredox decarboxylative C-C bond formation at room temperature afforded the corresponding cyclic compounds in good yields with tolerance of some functional groups.

  18. Particle-facilitated lead and arsenic transport in abandoned mine sites soil influenced by simulated acid rain.

    PubMed

    Shaoping, Hu; Xincai, Chen; Jiyan, Shi; Yingxu, Chen; Qi, Lin

    2008-05-01

    The role of acid rain in affecting Pb and As transport from mine tailings was investigated by pumping simulated acid rain at a infiltration rate of 10.2 cm/h through soil columns. Simulated acid rain with pH of 3.0, 4.5 and 5.6 were used as leaching solutions. Results showed that 86.9-95.9% of Pb and 90-91.8% of As eluted from the columns were adsorbed by particles in the leachates. Scanning electron microscopy (SEM) analysis showed that particles released from the columns were mainly composed of flocculated aggregates and plate or rod shaped discrete grains. Transmission electron microscopy (TEM) coupled with energy dispersive X-ray analysis (EDX) showed that these particles were predominantly silicate minerals. Results from our experiments demonstrated that when rapid infiltration conditions or a rainstorm exist, particle-facilitated transport of contaminants is likely to the dominant metal transport pathway influenced by acid rain.

  19. Collaborative Teaching Strategies Lead to Retention of Skills in Acid-Base Physiology: A 2-Yr Follow-Up Study

    ERIC Educational Resources Information Center

    Hartmann, Jacob P.; Toksvang, Linea Natalie; Berg, Ronan M. G.

    2015-01-01

    A basic understanding of acid-base physiology is critical for the correct assessment of arterial blood gases in the clinical setting. In this context, collaborative teaching strategies in the undergraduate classroom setting may be useful, since it has been reported to enhance both transfer and retention of learned material in a time-efficient…

  20. Recent Advances in Nucleic Acid Binding Aspects of Berberine Analogs and Implications for Drug Design.

    PubMed

    Bhowmik, Debipreeta; Kumar, Gopinatha Suresh

    2016-01-01

    Berberine is one of the most widely known alkaloids belonging to the protoberberine group exhibiting myriad therapeutic properties. The anticancer potency of berberine appears to derive from its multiple actions including strong interaction with nucleic acids exhibiting adenine-thymine base pair specificity, inhibition of the enzymes topoisomerases and telomerases, and stabilizing the quadruplex structures. It was realized that the development of berberine as a potential anticancer agent necessitates enhancing its nucleic acid binding efficacy through appropriate structural modifications. More recently a number of such approaches have been attempted in various laboratories with great success. Several derivatives have been synthesized mostly with substitutions at the 8, 9 and 13 positions of the isoquinoline chromophore, and studied for enhanced nucleic acid binding activity. In this article, we present an up to date review of the details of the interaction of berberine and several of its important synthetic 8, 9 and 13 substituted derivatives with various nucleic acid structures reported recently. These studies provide interesting knowledge on the mode, mechanism, sequence and structural specificity of the binding of berberine derivatives and correlate structural and energetic aspects of the interaction providing better understanding of the structure- activity relations for designing and development of berberine based therapeutic agents with higher efficacy and therapeutic potential.