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Sample records for electrical degradation ried

  1. Capsule fabrication for in-situ measurement of radiation induced electrical degradation (RIED) of ceramics in HFIR

    SciTech Connect

    Eatherly, W.S.; Heatherly, D.W.; Hurst, M.T.; Qualls, A.L.

    1996-04-01

    A collaborative DOE/Monbusho series of irradiation experiments is being implemented to determine, in situ, the effects of irradiation on the electrical resistivity of ceramic materials. The first experiment, TRIST-ER1, has been designed to irradiate 15 Al{sub 2}O{sub 3} test specimens at 450{degrees}C in an RB position of the High Flux Isotope Reactor (HFIR). Each test specimen is located in a sealed vanadium subcapsule with instrumentation provided to each subcapsule to measure temperature and resistance, and to place a biasing voltage across the specimen. Twelve of the specimens will be biased with 200 V/mm across the sample at all times, while three will not be biased, but can be if so desired during the irradiation. The experiment design, component fabrication, and subcapsule assembly have been completed. A three cycle irradiation, to a fast neutron (E>0.1 MeV) fluence of about 3x10{sup 25}n/m{sup 2} ({approx}3 dpa in Al{sub 2}O{sub 3}), is expected to begin early in March 1996.

  2. Data acquisition system used in radiation induced electrical degradation experiments

    SciTech Connect

    White, D.P.

    1995-04-01

    Radiation induced electrical degradation (RIED) of ceramic materials has recently been reported and is the topic of much research at the present time. The object of this report is to describe the data acquisition system for an experiment designed to study RIED at the High Flux Beam Reactor (HFBR) at Brookhaven National Laboratory.

  3. Minority lifetime degradation of silicon wafers after electric zone melting

    NASA Astrophysics Data System (ADS)

    Wu, M. C.; Yang, C. F.; Lan, C. W.

    2015-06-01

    The degradation of minority lifetime of mono- and multi-crystalline silicon wafers after electric zone melting, a simple and contamination-free process, was investigated. The thermal-stress induced dislocations were responsible to the degradation; however, the grain size also played a crucial role. It was believed that the grain boundaries helped the relaxation of thermal stress, so that the degradation was reduced as the grain size decreased. In addition to lifetime mapping and etch pit density, photoluminescence mapping was also used to examine the electrically active defects after zone melting. Factors affecting lifetime degradation of silicon wafers after electric zone melting were examined. Small-grain multi-crystalline wafers showed better lifetime after zone melting. Twining area showed better lifetime. The formation of new grains relaxed the thermal stress mitigating lifetime degradation.

  4. Electrical Stimulation of Microbial PCB Degradation in Sediment

    PubMed Central

    Chun, Chan Lan; Payne, Rayford B.; Sowers, Kevin R.; May, Harold D.

    2012-01-01

    Bioremediation of polychlorinated biphenyls (PCBs) has been precluded in part by the lack of a cost-effective method to stimulate microbial degradation in situ. A common limitation is the lack of an effective method of providing electron donors and acceptors to promote in situ PCB biodegradation. Application of an electric potential to soil/sediment could be an effective means of providing electron-donors/-acceptors to PCB dechlorinating and degrading microorganisms. In this study, electrical stimulation of microbial PCB dechlorination/ degradation was examined in sediment maintained under simulated in situ conditions. Voltage was applied to open microcosms filled with PCB-impacted (Aroclor 1242) freshwater sediment from a Superfund site (Fox River, WI). The effect of applied low voltages (1.5 to 3.0V) on the microbial transformation of PCBs was determined with: 1) spiked PCBs, and 2) indigenous weathered PCBs. The results indicate that both oxidative and reductive microbial transformation of the spiked PCBs was stimulated but oxidation was dominant and most effective with higher voltage. Chlorobenzoates were produced as oxidation metabolites of the spiked PCBs, but increasing voltage enhanced chlorobenzoate consumption, indicating that overall degradation was enhanced. In the case of weathered PCBs, the total concentration decreased 40–60% in microcosms exposed to electric current while no significant decrease of PCB concentration was observed in control reactors (0 V or sterilized). Single congener analysis of the weathered PCBs showed significant loss of di- to penta-chlorinated congeners, indicating that microbial activity was not limited to anaerobic dechlorination of only higher chlorinated congeners. Degradation was most apparent with the application of only 1.5 V where anodic O2 was not generated, indicating a mechanism of degradation independent of electrolytic O2. Low voltage stimulation of the microbial degradation of weathered PCBs observed in this

  5. Electrical stimulation of microbial PCB degradation in sediment.

    PubMed

    Chun, Chan Lan; Payne, Rayford B; Sowers, Kevin R; May, Harold D

    2013-01-01

    Bioremediation of polychlorinated biphenyls (PCBs) has been precluded in part by the lack of a cost-effective method to stimulate microbial degradation in situ. A common limitation is the lack of an effective method of providing electron donors and acceptors to promote in situ PCB biodegradation. Application of an electric potential to soil/sediment could be an effective means of providing electron-donors/-acceptors to PCB dechlorinating and degrading microorganisms. In this study, electrical stimulation of microbial PCB dechlorination/degradation was examined in sediment maintained under simulated in situ conditions. Voltage was applied to open microcosms filled with PCB-impacted (Aroclor 1242) freshwater sediment from a Superfund site (Fox River, WI). The effect of applied low voltages (1.5-3.0 V) on the microbial transformation of PCBs was determined with: 1) spiked PCBs, and 2) indigenous weathered PCBs. The results indicate that both oxidative and reductive microbial transformation of the spiked PCBs was stimulated but oxidation was dominant and most effective with higher voltage. Chlorobenzoates were produced as oxidation metabolites of the spiked PCBs, but increasing voltage enhanced chlorobenzoate consumption, indicating that overall degradation was enhanced. In the case of weathered PCBs, the total concentration decreased 40-60% in microcosms exposed to electric current while no significant decrease of PCB concentration was observed in control reactors (0 V or sterilized). Single congener analysis of the weathered PCBs showed significant loss of di- to penta-chlorinated congeners, indicating that microbial activity was not limited to anaerobic dechlorination of only higher chlorinated congeners. Degradation was most apparent with the application of only 1.5 V where anodic O(2) was not generated, indicating a mechanism of degradation independent of electrolytic O(2). Low voltage stimulation of the microbial degradation of weathered PCBs observed in this

  6. Microbial Electricity Generation Enhances Decabromodiphenyl Ether (BDE-209) Degradation

    PubMed Central

    Yang, Yonggang; Xu, Meiying; He, Zhili; Guo, Jun; Sun, Guoping; Zhou, Jizhong

    2013-01-01

    Due to environmental persistence and biotoxicity of polybrominated diphenyl ethers (PBDEs), it is urgent to develop potential technologies to remediate PBDEs. Introducing electrodes for microbial electricity generation to stimulate the anaerobic degradation of organic pollutants is highly promising for bioremediation. However, it is still not clear whether the degradation of PBDEs could be promoted by this strategy. In this study, we hypothesized that the degradation of PBDEs (e.g., BDE-209) would be enhanced under microbial electricity generation condition. The functional compositions and structures of microbial communities in closed-circuit microbial fuel cell (c-MFC) and open-circuit microbial fuel cell (o-MFC) systems for BDE-209 degradation were detected by a comprehensive functional gene array, GeoChip 4.0, and linked with PBDE degradations. The results indicated that distinctly different microbial community structures were formed between c-MFCs and o-MFCs, and that lower concentrations of BDE-209 and the resulting lower brominated PBDE products were detected in c-MFCs after 70-day performance. The diversity and abundance of a variety of functional genes in c-MFCs were significantly higher than those in o-MFCs. Most genes involved in chlorinated solvent reductive dechlorination, hydroxylation, methoxylation and aromatic hydrocarbon degradation were highly enriched in c-MFCs and significantly positively correlated with the removal of PBDEs. Various other microbial functional genes for carbon, nitrogen, phosphorus and sulfur cycling, as well as energy transformation process, were also significantly increased in c-MFCs. Together, these results suggest that PBDE degradation could be enhanced by introducing the electrodes for microbial electricity generation and by specifically stimulating microbial functional genes. PMID:23940625

  7. Microbial electricity generation enhances decabromodiphenyl ether (BDE-209) degradation.

    PubMed

    Yang, Yonggang; Xu, Meiying; He, Zhili; Guo, Jun; Sun, Guoping; Zhou, Jizhong

    2013-01-01

    Due to environmental persistence and biotoxicity of polybrominated diphenyl ethers (PBDEs), it is urgent to develop potential technologies to remediate PBDEs. Introducing electrodes for microbial electricity generation to stimulate the anaerobic degradation of organic pollutants is highly promising for bioremediation. However, it is still not clear whether the degradation of PBDEs could be promoted by this strategy. In this study, we hypothesized that the degradation of PBDEs (e.g., BDE-209) would be enhanced under microbial electricity generation condition. The functional compositions and structures of microbial communities in closed-circuit microbial fuel cell (c-MFC) and open-circuit microbial fuel cell (o-MFC) systems for BDE-209 degradation were detected by a comprehensive functional gene array, GeoChip 4.0, and linked with PBDE degradations. The results indicated that distinctly different microbial community structures were formed between c-MFCs and o-MFCs, and that lower concentrations of BDE-209 and the resulting lower brominated PBDE products were detected in c-MFCs after 70-day performance. The diversity and abundance of a variety of functional genes in c-MFCs were significantly higher than those in o-MFCs. Most genes involved in chlorinated solvent reductive dechlorination, hydroxylation, methoxylation and aromatic hydrocarbon degradation were highly enriched in c-MFCs and significantly positively correlated with the removal of PBDEs. Various other microbial functional genes for carbon, nitrogen, phosphorus and sulfur cycling, as well as energy transformation process, were also significantly increased in c-MFCs. Together, these results suggest that PBDE degradation could be enhanced by introducing the electrodes for microbial electricity generation and by specifically stimulating microbial functional genes.

  8. International Space Station Alpha electric power system performance degradation

    NASA Astrophysics Data System (ADS)

    Lu, Cheng-Yi; Hague, Lisa; Padhye, Vidya; Hill, Robert

    1995-07-01

    Performance of the International Space Station Alpha (ISSA) United States On-Orbit Segment (USOS) Electric Power System (EPS) will be degraded through the mission life of the station. The power generation photovoltaic array and thermal control radiator will be directly exposed to the natural environment and the environment induced after the station is built. These environmental effects result in lower array current and voltage output as well as lower radiator heat rejection capability. Aging is the major cause for the energy storage nickel-hydrogen (NiH2) battery performance degradation. Over time, there is an increase in the internal impedance, which results in a decreased efficiency as the battery ages. Design of the ISSA EPS takes into consideration the various equipment degradation modes, to make it compatible with the environments and to meet power, lifetime, and performance requirements.

  9. Electrical and capacitive methods for detecting degradation in wire insulation

    NASA Astrophysics Data System (ADS)

    Sheldon, Robert T.

    Motivated by a need within the aerospace industry to detect and characterize degradation in the insulation of onboard wires, this thesis reports testing of several extant methods and development of novel capacitive sensors. This work focuses on measuring the electrical parameters resistance and capacitance that are directly related to the material parameters conductivity and permittivity, respectively, of the insulation. It is shown that the measured electrical parameters successfully indicate degradation in the wire insulation. Insulation resistance tests were performed on 17 wire samples, removed from various locations on a retired aircraft, and compared with those conducted on pristine wire samples, in order to assess any change in conductivity exhibited by degraded insulation. Timed resistance tests were also performed to determine the dielectric absorption of the insulation. Curved patch-electrode sensors were applied in order to measure the capacitance and dissipation factor of the same wires. Results from the resistive and capacitive tests both identified wire samples that were apparently significantly degraded, as indicated qualitatively by visual inspection. Further, a novel cylindrical interdigital capacitive sensor was developed. The interdigital sensor is designed with the goal of achieving a good signal-to-noise ratio, the lowest instrument error possible at 1 MHz, full circumferential coverage of the wire, and the ability to adjust the penetration depth of the electric field into the insulation layer by adjusting the separation of the sensor digits. With the aim, ultimately, of quantitative measurement of insulation complex permittivity, a numerical model was developed using a cylindrical Green's function and the Method of Moments to calculate theoretically the capacitance of the interdigital sensor. Benchmark experiments were carried out on large-scale dielectric-coated conductive cylinders to test the validity of the model. Experimental results

  10. Electrical integrity of oxides in a radiation field

    SciTech Connect

    Zinkle, S.J.; Kinoshita, C.

    1996-04-01

    In the absence of an applied electric field, irradiation generally produces a decrease in the permanent (beam-off) electrical conductivity of ceramic insulators. However, in the past 6 years several research groups have reported a phenomenon known as radiation induced electrical degradation (RIED), which produces significant permanent increases in the electrical conductivity of ceramic insulators irradiated with an applied electric field. RIED has been reported to occur at temperatures between 420 and 800 K with applied electric fields as low as 20 V/mm.

  11. Irradiation imposed degradation of the mechanical and electrical properties of electrical insulation for future accelerator magnets

    SciTech Connect

    Polinski, J.; Chorowski, M.; Bogdan, P.; Strychalski, M.; Rijk, G. de

    2014-01-27

    Future accelerators will make extensive use of superconductors made of Nb{sub 3}Sn, which allows higher magnetic fields than NbTi. However, the wind-and-react technology of Nb{sub 3}Sn superconducting magnet production makes polyimide Kapton® non applicable for the coils' electrical insulation. A Nb{sub 3}Sn technology compatible insulation material should be characterized by high radiation resistivity, good thermal conductivity, and excellent mechanical properties. Candidate materials for the electrical insulation of future accelerator's magnet coils have to be radiation certified with respect to potential degradation of their electrical, thermal, and mechanical properties. This contribution presents procedures and results of tests of the electrical and mechanical properties of DGEBA epoxy + D400 hardener, which is one of the candidates for the electrical insulation of future magnets. Two test sample types have been used to determine the material degradation due to irradiation: a untreated one (unirradiated) and irradiated at 77 K with 11 kGy/min intense, 4MeV energy electrons beam to a total dose of 50 MGy.

  12. Silicone oil contamination and electrical contact resistance degradation of low-force gold contacts.

    SciTech Connect

    Dugger, Michael Thomas; Dickrell, Daniel John, III

    2006-02-01

    Hot-switched low-force gold electrical contact testing was performed using a nanomechanical test apparatus to ascertain the sensitivity of simulated microelectromechanical systems (MEMS) contact to silicone oil contamination. The observed cyclic contact resistance degradation was dependent on both closure rate and noncontact applied voltage. The decomposition of silicone oil from electrical arcing was hypothesized as the degradation mechanism.

  13. Distribution of electrical energy consumption for the efficient degradation control of THMs mixture in sonophotolytic process.

    PubMed

    Park, Beomguk; Cho, Eunju; Son, Younggyu; Khim, Jeehyeong

    2014-11-01

    Sonophotolytic degradation of THMs mixture with different electrical energy ratio was carried out for efficient design of process. The total consumed electrical energy was fixed around 50W, and five different energy conditions were applied. The maximum degradation rate showed in conditions of US:UV=1:3 and US:UV=0:4. This is because the photolytic degradation of bromate compounds is dominant degradation mechanism for THMs removal. However, the fastest degradation of total organic carbon was observed in a condition of US:UV=1:3. Because hydrogen peroxide generated by sonication was effectively dissociated to hydroxyl radicals by ultraviolet, the concentration of hydroxyl radical was maintained high. This mechanism provided additional degradation of organics. This result was supported by comparison between the concentration of hydrogen peroxide sole and combined process. Consequently, the optimal energy ratio was US:UV=1:3 for degradation of THMs in sonophotolytic process.

  14. Chemical Degradation of the Cathodic Electrical Contact Between Carbon and Cast Iron in Aluminum Production Cells

    NASA Astrophysics Data System (ADS)

    Brassard, Martin; Désilets, Martin; Soucy, Gervais; Bilodeau, Jean-François; Forté, Martin

    2017-02-01

    The cathodic carbon to cast iron electrical contact degradation is one of the factors to consider in the cathode voltage drop (CVD) increase over the lifetime of aluminum production cells. Lab-scale experiments were carried out to study the cast iron to carbon interface chemical degradation and the impact of important cell parameters like temperature and bath chemistry. Laboratory degradation results were compared with industrial samples. A thermoelectric Ansys numerical model was then used to predict the effect of cast iron surface degradation over CVD. Results show that the aluminum formation on the cast iron surface and its subsequent diffusion creates an immiscible mixture of Fe-Al metal alloy and electrolytic bath. Disparities were also observed between industrial samples taken from two different technologies, suggesting that the degradation can be slowed down. Thermoelectric calculations finally revealed that the impact of the contact resistance augmentation is by far greater than the cast iron degradation.

  15. Correlation of electrical reactor cable failure with materials degradation

    SciTech Connect

    Stuetzer, O.M.

    1986-03-01

    Complete circuit failure (shortout) of electrical cables typically used in nuclear power plant containments is investigated. Failure modes are correlated with the mechanical deterioration of the elastomeric cable materials. It is found that for normal reactor operation, electrical cables are reliable and safe over very long periods. During high temperature excursions, however, cables pulled across corners under high stress may short out due to conductor creep. Severe cracking will occur in short times during high temperatures (>150/sup 0/C) and in times of the order of years at elevated temperatures (100/sup 0/C to 140/sup 0/C). A theoretical treatment of stress distribution responsible for creep and for cracking by J.E. Reaugh of Science Applications, Inc. is contained in the Appendix. 29 refs., 32 figs.

  16. Short-pulsed, electric-discharge degradation of toxic and sludge wastes

    SciTech Connect

    Rosocha, L.A.; Bystritskii, V.M.; Wessel, F.J.

    1998-12-01

    This is the final report of a three-year, Directed Research and Development (LDRD) project funded by the Los Alamos National Laboratory (LANL). The project was a collaborative effort with the University of California at Irvine (UCI), which was the lead project performer. Short-pulse, electric-discharge streamers were used to degrade aromatic and chlorinated compounds in water aerosols. An atomizer supplies 10--50 {micro}m aerosol droplets to a discharge chamber containing thin wires that are driven by electric pulses of 50--90 kV amplitude, 50--150 ns pulse duration, and 100 Hz repetition rate. The combination of a high electric field, large H{sub 2}O dielectric constant and atomization provide efficient degradation of organic molecules including: paranitrophenol, di-chlorophenol and perchloroethylene. The specific energy input for degradation of a pollutant molecule depends on the particular compound, its concentration, and the operational parameters of the discharge.

  17. Effect of electric intensity on the microbial degradation of petroleum pollutants in soil.

    PubMed

    Li, Tingting; Guo, Shuhai; Wu, Bo; Li, Fengmei; Niu, Zhixin

    2010-01-01

    Electro-bioremediation is an innovative method to remedy organic-polluted soil. However, the principle of electrokinetic technology enhancing the function of microbes, especially the relationship of electric intensity and biodegradation efficiency, is poorly investigated. Petroleum was employed as a target organic pollutant at a level of 50 g/kg (mass of petroleum/mass of dry soil). A direct current power supply was used for tests with a constant direct current electric voltage (1.0 V/cm). The petroleum concentrations were measured at 3275-3285 nm after extraction using hexane, the group composition of crude oil was analyzed by column chromatography. The water content of soil was kept 25% (m/m). The results indicated the degradation process was divided into two periods: from day 1 to day 40, from day 41 to day 100. The treatment of soil with an appropriate electric field led the bacteria to have a persistent effect in the whole period of 100 days. The highest biodegradation efficiency of 45.5% was obtained after treatment with electric current and bacteria. The electric-bioremediation had a positive effect on alkane degradation. The degradation rate of alkane was 1.6 times higher in the soil exposed to electric current than that treated with bacteria for 100 days. A proper direct current could stimulate the microbial activities and accelerate the biodegradation of petroleum. There was a positive correlation between the electric intensities and the petroleum bioremediation efficiencies with a coefficient of 0.9599.

  18. Swift heavy ion irradiation induced electrical degradation in deca-nanometer MOSFETs

    NASA Astrophysics Data System (ADS)

    Ma, Yao; Yang, Zhimei; Gong, Min; Gao, Bo; Li, Yun; Lin, Wei; Li, Jinbo; Xia, Zhuohui

    2016-09-01

    In this work, degradation of the electrical characteristics of 65 nm nMOSFETs under swift heavy ion irradiation is investigated. It was found that a heavy ion can generate a localized region of physical damage (ion latent track) in the gate oxide. This is the likely cause for the increased gate leakage current and soft breakdown (SBD) then hard breakdown (HBD) of the gate oxide. Except in the case of HBD, the devices retain their functionality but with degraded transconductance. The degraded gate oxide exhibits early breakdown behavior compatible with the model of defect generation and percolation path formation in the percolation model.

  19. Evaluation of non-thermal effects of electricity on ascorbic acid and carotenoid degradation in acerola pulp during ohmic heating.

    PubMed

    Jaeschke, Débora Pez; Marczak, Ligia Damasceno Ferreira; Mercali, Giovana Domeneghini

    2016-05-15

    The effect of electric field on ascorbic acid and carotenoid degradation in acerola pulp during ohmic heating was evaluated. Ascorbic acid kinetic degradation was evaluated at 80, 85, 90 and 95°C during 60 min of thermal treatment by ohmic and conventional heating. Carotenoid degradation was evaluated at 90 and 95°C after 50 min of treatment. The different temperatures evaluated showed the same effect on degradation rates. To investigate the influence of oxygen concentration on the degradation process, ohmic heating was also carried out under rich and poor oxygen modified atmospheres at 90°C. Ascorbic acid and carotenoid degradation was higher under a rich oxygen atmosphere, indicating that oxygen is the limiting reagent of the degradation reaction. Ascorbic acid and carotenoid degradation was similar for both heating technologies, demonstrating that the presence of the oscillating electric field did not influence the mechanisms and rates of reactions associated with the degradation process.

  20. Radiation-induced electrical degradation experiments in the Japan materials testing reactor

    SciTech Connect

    Farnum, E.; Scharborough, K.; Shikama, Tatsuo

    1995-04-01

    The objective of this experiment is to determine the extent of degradation during neutron irradiation of electrical and optical properties of candidate dielectric materials. The goals are to identify promising dielectrics for ITER and other fusion machines for diagnostic applications and establish the basis for optimization of candidate materials. An experiment to measure radiation-induced electrical degradation (REID) in sapphire and MgO-insulated cables was conducted at the JMTR light water reactor. The materials were irradiated at about 260 {degree}C to a fluence of 3{times}10{sup 24} n/m{sup 2} (E>1 MeV) with an applied DC electric field between 100 kV/m and 500 kV/m.

  1. Chitin degradation and electricity generation by Aeromonas hydrophila in microbial fuel cells.

    PubMed

    Li, Shan-Wei; He, Hui; Zeng, Raymond J; Sheng, Guo-Ping

    2017-02-01

    Chitin is one of the most abundant biopolymers in nature and the main composition of shrimp and crab shells (usually as food wastes). Thus it is essential to investigate the potential of degrading chitin for energy recovery. This study investigated the anaerobic degradation of chitin by Aeromonas hydrophila, a chitinolytic and popular electroactive bacterium, in both fermentation and microbial fuel cell (MFC) systems. The primary chitin metabolites produced in MFC were succinate, lactate, acetate, formate, and ethanol. The total metabolite concentration from chitin degradation increased seven-fold in MFC compared to the fermentation system, as well as additional electricity generation. Moreover, A. hydrophila degraded GlcNAc (the intermediate of chitin hydrolysis) significantly faster (0.97 and 0.94 mM C/d/mM-GlcNAc) than chitin (0.13 and 0.03 mM C/d/mM-GlcNAc) in MFC and fermentation systems, indicating that extracellular hydrolysis of chitin was the rate-limiting step and this step could be accelerated in MFC. Furthermore, more chemicals produced by the addition of exogenous mediators in MFC. This study proves that the chitin could be degraded effectively by an electroactive bacterium in MFC, and our results suggest that this bioelectrochemical system might be useful for the degradation of recalcitrant biomass to recover energy.

  2. [Electricity generation and contaminants degradation performances of a microbial fuel cell fed with Dioscorea zingiberensis wastewater].

    PubMed

    Li, Hui; Zhu, Xiu-Ping; Xu, Nan; Ni, Jin-Ren

    2011-01-01

    The electricity generation performance of a microbial fuel cell (MFC) utilizing Dioscorea zingiberensis wastewater was studied with an H-shape reactor. Indexes including pH, conductivity, oxidation peak potential and chemical oxygen demand (COD) of the anolyte were monitored to investigate the contaminants degradation performance of the MFC during the electricity generation process, besides, contaminant ingredients in anodic influent and effluent were analyzed by GC-MS and IR spectra as well. The maximum power density of the MFC could achieve 118.1 mW/m2 and the internal resistance was about 480 omega. Connected with a 1 000 omega external resistance, the output potential was about 0.4 V. Fed with 5 mL Dioscorea zingiberensis wastewater, the electricity generation lasted about 133 h and the coulombic efficiency was about 3.93%. At the end of electricity generation cycle, COD decreased by 90.1% while NH4(+) -N decreased by 66.8%. Furfural compounds, phenols and some other complicated organics could be decomposed and utilized in the electricity generation process, and the residual contaminants in effluent included some long-chain fatty acids, esters, ethers, and esters with benzene ring, cycloalkanes, cycloolefins, etc. The results indicate that MFC, which can degrade and utilize the organic contaminants in Dioscorea zingiberensis wastewater simultaneously, provides a new approach for resource recovery treatment of Dioscorea zingiberensis wastewater.

  3. Freezing/thawing effect on sewage sludge degradation and electricity generation in microbial fuel cell.

    PubMed

    Chen, Yuejia; Jiang, Junqiu; Zhao, Qingliang

    2014-01-01

    The effect of sludge freezing/thawing on its disintegration and subsequent use as substrate in a microbial fuel cell (MFC) was investigated to enhance organic matter degradation and electricity generation. Experimental results indicated that long freezing time (more than 48 h) was effective in disintegrating the sludge collected from the secondary sedimentation tank of a wastewater treatment plant. Freezing/thawing pretreatment could enhance the degradation of total chemical oxygen demand (COD) and electricity generation in MFC due to the higher concentration of soluble COD and ammonium nitrogen available in the pretreated sludge. The removal efficiency of total COD was increased from 25.3% (raw sludge as substrate) to 66.2% and the maximum power output was increased from 8.9 (raw sludge as substrate) to 10.2 W/m³ in MFC.

  4. Intrinsic Gettering of RIE Damage on Silicon Studied by Scanning DLTS and EBIC Methods

    NASA Astrophysics Data System (ADS)

    Ikuta, Kenji

    1987-07-01

    The degradation of silicon substrates due to reactive ion etching (RIE) damage and its elimination by intrinsic gettering (IG) are studied using scanning DLTS (SDLTS) and EBIC methods in an SEM. The SDLTS study clarifies that a hole trap of Ev+0.37 eV is introduced uniformly by RIE. Surface stacking faults are grown from latent defects associated with the trap during subsequent annealing. The EBIC analysis can predict macroscopic lifetime degradation due to the defect generation. IG is found to be successful in eliminating the degradation, when subsequent annealing is performed in O2, but not successful in N2 annealing. The gettering mechanism for RIE damage is also discussed in terms of the dependence on the annealing ambient.

  5. Kinetic laws of the process of thermal degradation of electric brush articles based on synthetic binders

    SciTech Connect

    Komarova, T.V.; Derbenev, V.A.; Fedoseev, S.D.; Shamkina, N.A.; Skoblik, T.I.

    1982-01-01

    An investigation has been made of the process of thermal degradation of electric brush articles based on a thermoplastic binder. It has been shown that the curves of gas evolution with various methods of heating have the same nature, the highest rate of evolution of volatile matter under the conditions of thermal shock being observed in the first five minutes. The kinetic characteristics of the process have been calculated.

  6. Effect of Mn Addition on dc-Electrical Degradation of Multilayer Ceramic Capacitor with Ni Internal Electrode

    NASA Astrophysics Data System (ADS)

    Morita, Koichiro; Mizuno, Youichi; Chazono, Hirokazu; Kishi, Hiroshi

    2002-11-01

    The effect of Mn addition on the microstructure and electrical properties, especially on the dc-electrical degradation, of the X7R-type multilayer ceramic capacitor with Ni internal electrode (Ni-MLCC) with thin active layers was investigated. As the amount of Mn increased, grain growth was suppressed, and the temperature characteristic (TC) curve was flattened. I-V characteristic measurements revealed that nonlinearity coefficient (α) at a high electric field of more than 10 V/μm was decreased, and the lifetime during the highly accelerated lifetime testing (HALT) under 20 V/μm was improved, as the Mn content increased. It was found that Mn addition caused the change of the electrical properties of the grain boundary (GB). The effect of Mn on dc-electrical degradation during HALT was investigated by introducing impedance measurement at elevated temperatures from the microstructural view point. The roles of Mn on dc-electrical degradation during HALT were proposed.

  7. Fatigue degradation and electric recovery in Silicon solar cells embedded in photovoltaic modules

    PubMed Central

    Paggi, Marco; Berardone, Irene; Infuso, Andrea; Corrado, Mauro

    2014-01-01

    Cracking in Silicon solar cells is an important factor for the electrical power-loss of photovoltaic modules. Simple geometrical criteria identifying the amount of inactive cell areas depending on the position of cracks with respect to the main electric conductors have been proposed in the literature to predict worst case scenarios. Here we present an experimental study based on the electroluminescence (EL) technique showing that crack propagation in monocrystalline Silicon cells embedded in photovoltaic (PV) modules is a much more complex phenomenon. In spite of the very brittle nature of Silicon, due to the action of the encapsulating polymer and residual thermo-elastic stresses, cracked regions can recover the electric conductivity during mechanical unloading due to crack closure. During cyclic bending, fatigue degradation is reported. This pinpoints the importance of reducing cyclic stresses caused by vibrations due to transportation and use, in order to limit the effect of cracking in Silicon cells. PMID:24675974

  8. Plug-in hybrid electric vehicles: battery degradation, grid support, emissions, and battery size tradeoffs

    NASA Astrophysics Data System (ADS)

    Peterson, Scott B.

    Plug-in hybrid electric vehicles (PHEVs) may become a substantial part of the transportation fleet in a decade or two. This dissertation investigates battery degradation, and how introducing PHEVs may influence the electricity grid, emissions, and petroleum use in the US. It examines the effects of combined driving and vehicle-to-grid (V2G) usage on lifetime performance of commercial Li-ion cells. The testing shows promising capacity fade performance: more than 95% of the original cell capacity remains after thousands of driving days. Statistical analyses indicate that rapid vehicle motive cycling degraded the cells more than slower, V2G galvanostatic cycling. These data are used to examine the potential economic implications of using vehicle batteries to store grid electricity generated at off-peak hours for off-vehicle use during peak hours. The maximum annual profit with perfect market information and no battery degradation cost ranged from ˜US140 to 250 in the three cities. If measured battery degradation is applied the maximum annual profit decreases to ˜10-120. The dissertation predicts the increase in electricity load and emissions due to vehicle battery charging in PJM and NYISO with the current generators, with a 50/tonne CO2 price, and with existing coal generators retrofitted with 80% CO2 capture. It also models emissions using natural gas or wind+gas. We examined PHEV fleet percentages between 0.4 and 50%. Compared to 2020 CAFE standards, net CO2 emissions in New York are reduced by switching from gasoline to electricity; coal-heavy PJM shows smaller benefits unless coal units are fitted with CCS or replaced with lower CO2 generation. NOX is reduced in both RTOs, but there is upward pressure on SO2 emissions or allowance prices under a cap. Finally the dissertation compares increasing the all-electric range (AER) of PHEVs to installing charging infrastructure. Fuel use was modeled with National Household Travel Survey and Greenhouse Gasses, Regulated

  9. Kinetics of substrate degradation and electricity generation in anodic denitrification microbial fuel cell (AD-MFC).

    PubMed

    Zhang, Jiqiang; Zheng, Ping; Zhang, Meng; Chen, Hui; Chen, Tingting; Xie, Zuofu; Cai, Jing; Abbas, Ghulam

    2013-12-01

    Effect of substrate concentration on substrate degradation and electricity generation in anodic denitrification microbial fuel cell (AD-MFC) was investigated over a broad range of substrate concentrations. Substrate degradation rates and power generation could be promoted with increasing substrate concentration in a certain range, but both of them would be inhibited at high substrate concentrations. Maximum denitrification rate of 1.26 ± 0.01 kg NO(-)-N/m(3)d and maximum output voltage of 1016.75 ± 4.74 mV could be achieved when initial NO3(-)-N concentration was 1999.95 ± 2.86 mg/L. Based on Han-Levenspiel model, kinetics of substrate degradation and power generation in the AD-MFC were established. According to the kinetic model, the half-saturation coefficient and the critical inhibitory concentration for nitrate were more than 200 and 4300 mg/L, respectively. The results demonstrated that AD-MFC was capable of treating nitrate-containing wastewater and generating electricity simultaneously, and tolerant to high strength nitrate-containing wastewater.

  10. Influence of supporting electrolyte in electricity generation and degradation of organic pollutants in photocatalytic fuel cell.

    PubMed

    Khalik, Wan Fadhilah; Ong, Soon-An; Ho, Li-Ngee; Wong, Yee-Shian; Voon, Chun-Hong; Yusuf, Sara Yasina; Yusoff, Nik Athirah; Lee, Sin-Li

    2016-08-01

    This study investigated the effect of different supporting electrolyte (Na2SO4, MgSO4, NaCl) in degradation of Reactive Black 5 (RB5) and generation of electricity. Zinc oxide (ZnO) was immobilized onto carbon felt acted as photoanode, while Pt-coated carbon paper as photocathode was placed in a single chamber photocatalytic fuel cell, which then irradiated by UV lamp for 24 h. The degradation and mineralization of RB5 with 0.1 M NaCl rapidly decreased after 24-h irradiation time, followed by MgSO4, Na2SO4 and without electrolyte. The voltage outputs for Na2SO4, MgSO4 and NaCl were 908, 628 and 523 mV, respectively, after 24-h irradiation time; meanwhile, their short-circuit current density, J SC, was 1.3, 1.2 and 1.05 mA cm(-2), respectively. The power densities for Na2SO4, MgSO4 and NaCl were 0.335, 0.256 and 0.245 mW cm(-2), respectively. On the other hand, for without supporting electrolyte, the voltage output and short-circuit current density was 271.6 mV and 0.055 mA cm(-2), respectively. The supporting electrolyte NaCl showed greater performance in degradation of RB5 and generation of electricity due to the formation of superoxide radical anions which enhance the degradation of dye. The mineralization of RB5 with different supporting electrolyte was measured through spectrum analysis and reduction in COD concentration.

  11. Quantifying electric vehicle battery degradation from driving vs. vehicle-to-grid services

    NASA Astrophysics Data System (ADS)

    Wang, Dai; Coignard, Jonathan; Zeng, Teng; Zhang, Cong; Saxena, Samveg

    2016-11-01

    The risk of accelerated electric vehicle battery degradation is commonly cited as a concern inhibiting the implementation of vehicle-to-grid (V2G) technology. However, little quantitative evidence exists in prior literature to refute or substantiate these concerns for different grid services that vehicles may offer. In this paper, a methodology is proposed to quantify electric vehicle (EV) battery degradation from driving only vs. driving and several vehicle-grid services, based on a semi-empirical lithium-ion battery capacity fade model. A detailed EV battery pack thermal model and EV powertrain model are utilized to capture the time-varying battery temperature and working parameters including current, internal resistance and state-of-charge (SOC), while an EV is driving and offering various grid services. We use the proposed method to simulate the battery degradation impacts from multiple vehicle-grid services including peak load shaving, frequency regulation and net load shaping. The degradation impact of these grid services is compared against baseline cases for driving and uncontrolled charging only, for several different cases of vehicle itineraries, driving distances, and climate conditions. Over the lifetime of a vehicle, our results show that battery wear is indeed increased when vehicles offer V2G grid services. However, the increased wear from V2G is inconsequential compared with naturally occurring battery wear (i.e. from driving and calendar ageing) when V2G services are offered only on days of the greatest grid need (20 days/year in our study). In the case of frequency regulation and peak load shaving V2G grid services offered 2 hours each day, battery wear remains minimal even if this grid service is offered every day over the vehicle lifetime. Our results suggest that an attractive tradeoff exists where vehicles can offer grid services on the highest value days for the grid with minimal impact on vehicle battery life.

  12. The roles of ozone and zeolite on reactive dye degradation in electrical discharge reactors.

    PubMed

    Peternel, L; Kusic, H; Koprivanac, N; Locke, B R

    2006-05-01

    In this study high voltage pulsed corona electrical discharge advanced oxidation processes (AOPs) were applied to bleach and degrade C.I. Reactive Green 8 and C.I. Reactive Red 45 organic dyes in water solutions. Two types of hybrid gas/liquid high voltage electrical discharge (corona) reactors, known as hybrid series and hybrid parallel were studied. The difference between these reactors relates to electrode configuration, which affects the amounts of ozone, hydrogen peroxide and hydroxyl radicals produced. Experiments were conducted using dye concentrations of 20 mgl(-1) and 75 mgl(-1), with and without NH4ZSM5 zeolite addition in order to determine possible effects of added solid particles to total process efficiency. The role of ozone in combination with zeolites was assessed through comparative direct ozonation experiments with ozone supplied by an ozone generator. UV/VIS spectrophotometric measurements and measurements of total organic carbon (TOC) were used for the determination of decolorization and mineralization rates.

  13. Simultaneous cellulose degradation and electricity production by Enterobacter cloacae in a microbial fuel cell.

    PubMed

    Rezaei, Farzaneh; Xing, Defeng; Wagner, Rachel; Regan, John M; Richard, Tom L; Logan, Bruce E

    2009-06-01

    Electricity can be directly generated by bacteria in microbial fuel cells (MFCs) from many different biodegradable substrates. When cellulose is used as the substrate, electricity generation requires a microbial community with both cellulolytic and exoelectrogenic activities. Cellulose degradation with electricity production by a pure culture has not been previously demonstrated without addition of an exogenous mediator. Using a specially designed U-tube MFC, we enriched a consortium of exoelectrogenic bacteria capable of using cellulose as the sole electron donor. After 19 dilution-to-extinction serial transfers of the consortium, 16S rRNA gene-based community analysis using denaturing gradient gel electrophoresis and band sequencing revealed that the dominant bacterium was Enterobacter cloacae. An isolate designated E. cloacae FR from the enrichment was found to be 100% identical to E. cloacae ATCC 13047(T) based on a partial 16S rRNA sequence. In polarization tests using the U-tube MFC and cellulose as a substrate, strain FR produced 4.9 +/- 0.01 mW/m(2), compared to 5.4 +/- 0.3 mW/m(2) for strain ATCC 13047(T). These results demonstrate for the first time that it is possible to generate electricity from cellulose using a single bacterial strain without exogenous mediators.

  14. Preparation of ZnS-graphene nanocomposites under electric furnace and photocatalytic degradation of organic dyes.

    PubMed

    Park, Hae Soo; Ko, Weon Bae

    2014-11-01

    Zinc sulfide (ZnS) nanoparticles were synthesized from zinc nitrate hexahydrate and thiourea under microwave irradiation. The ZnS-graphene nanocomposites were calcined in an electric furnace at 700 degrees C under an inert argon gas atmosphere for 2 hr. The heated ZnS-graphene nanocomposites were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and UV-vis spectrophotometry. After heat treatment, ZnS-graphene nanocomposites had a more porous and larger surface area, than the unheated ZnS-graphene nanocomposites. The photocatalytic activity of the heated ZnS-graphene nanocomposites in the degradation of organic dyes, such as methylene blue, methyl orange, and rhodamine B, under ultraviolet light at 254 nm by UV- vis spectrophotometer was evaluated and compared with that of the unheated ZnS nanoparticles, heated ZnS nanoparticles, unheated ZnS-graphene nanocomposites. Among the our experimental results as a photocatalyst, the heated ZnS-graphene nanocomposites exhibited remarkably higher photocatalytic degradation of organic dyes as compared to other nanomaterials such as unheated ZnS nanoparticles and heated ZnS-graphene nanocomposites.

  15. The Electrical and Structural analysis of degraded Single Junction Amorphous Silicon Solar Modules

    NASA Astrophysics Data System (ADS)

    Osayemwenre, Gilbert; Energy efficiency Team

    2015-03-01

    This paper outline a systematic approach used in evaluating the quality, performance and reliability of single junction amorphous silicon solar modules (a-Si:H). The analytical techniques include an electrical and structural analysis. These techniques were used to obtain a holistic view of the state of affairs of these readily available PV modules for small stand-alone systems. Specifically, current-voltage (I-V) characterization and scanning electron microscopy (SEM) will be presented as diagnostic tools in this article. The SEM (JEOL, JED-2300) was used to study the surface morphology of the affected region, results show structural damage in the affected regions. The experiment shows that the energy output of the modules varies a degradation variation of 2.5% to 25.7%, was observed. The detailed results will be presented in the final paper. In conclusion, this research established the degradation which occurs and correlate it to the morphological damage. The module with the worst case scenario has an efficiency of 59% decrease, this could be unacceptable in a device where stability is of priority. We sincerely thank GMDRC and Eskom for financing this project.

  16. MaRIE Undulator & XFEL Systems

    SciTech Connect

    Nguyen, Dinh Cong; Marksteiner, Quinn R.; Anisimov, Petr Mikhaylovich; Buechler, Cynthia Eileen

    2015-03-23

    The 22 slides in this presentation treat the subject under the following headings: MaRIE XFEL Performance Parameters, Input Electron Beam Parameters, Undulator Design, Genesis Simulations, Risks, and Summary It is concluded that time-dependent Genesis simulations show the MaRIE XFEL can deliver the number of photons within the required bandwidth, provided a number of assumptions are met; the highest risks are associated with the electron beam driving the XFEL undulator; and risks associated with the undulator and/or distributed seeding technique may be evaluated or retired by performing early validation experiments.

  17. [Electricity generation and quinoline degradation of pure strains and mixed strains in the microbial fuel cell].

    PubMed

    Chen, Shan-Shan; Zhang, Cui-Ping; Liu, Guang-Li; Zhang, Ren-Duo; Li, Ming-Chen; Quan, Xiang-Chun

    2010-09-01

    Microbial flora composition of microbial fuel cells (MFC) is important to the electricity generation. Four bacterium strains Q1, b, c and d which represent all different morphology of culturable bacterium were isolated from a MFC using 200 mg x L(-1) quinoline as the fuel and operating for at least 210 days. Strains Q1, c and d were Pseudomonas sp. based on 16S rDNA sequence analysis, while strain b was Burkholderia sp. Double-chamber MFCs using 200 mg x L(-1) quinoline and 300 mg x L(-1) glucose as the fuel and potassium ferricyanide as the electron acceptor were constructed. Results showed that strain b, c and d were non-electrogenesis. The electrical charges of MFC inoculated electrogenesis strain Q1 with non-electrogenesis strain b, c and d respectively were 3.00, 3.57 and 5.13C, and the columbic efficiency were 3.85%, 4.59% and 6.58%, which were all lower than that inoculated with pure Q1, because of the interspecific competition of electrogenesis and non-electrogenesis bacteria. Combinations of Q1 with the other three strains respectively resulted in 100% of quinoline degradation rates within 24h, which is better than pure cultures, that is, mixed microbial populations perform better in MFC when complex organics are used as the fuel. GC/MS analyses showed that only 2(1H)-quinolinone and phenol existed in the effluent of the MFC, which was inoculated with only Q1 or mixed bacteria.

  18. The influence of battery degradation level on the selected traction parameters of a light-duty electric vehicle

    NASA Astrophysics Data System (ADS)

    Juda, Z.; Noga, M.

    2016-09-01

    The article describes results of an analysis of the impact of degradation level of battery made in lead-acid technology on selected traction parameters of an electric light duty vehicle. Lead-acid batteries are still used in these types of vehicles. They do not require complex systems of performance management and monitoring and are easy to maintaining. Despite the basic disadvantage, which is the low value of energy density, low price is a decisive factor for their use in low-speed electric vehicles. The process of aging of the battery related with an increase in internal resistance of the cells and the loss of electric capacity of the battery was considered. A simplified model of cooperation of the DC electric motor with the battery assuming increased internal resistance was presented. In the paper the results of comparative traction research of the light-duty vehicle equipped with a set of new batteries and set of batteries having a significant degradation level were showed. The analysis of obtained results showed that the correct exploitation of the battery can slow down the processes of degradation and, thus, extend battery life cycle.

  19. Novel degradable co-polymers of polypyrrole support cell proliferation and enhance neurite out-growth with electrical stimulation.

    PubMed

    Durgam, Hymavathi; Sapp, Shawn; Deister, Curt; Khaing, Zin; Chang, Emily; Luebben, Silvia; Schmidt, Christine E

    2010-01-01

    Synthetic polymers such as polypyrrole (PPy) are gaining significance in neural studies because of their conductive properties. We evaluated two novel biodegradable block co-polymers of PPy with poly(epsilon-caprolactone) (PCL) and poly(ethyl cyanoacrylate) (PECA) for nerve regeneration applications. PPy-PCL and PPy-PECA co-polymers can be processed from solvent-based colloidal dispersions and have essentially the same or greater conductivity (32 S/cm for PPy-PCL, 19 S/cm for PPy-PECA) compared to the PPy homo-polymer (22 S/cm). The PPy portions of the co-polymers permit electrical stimulation whereas the PCL or PECA blocks enable degradation by hydrolysis. For in vitro tests, films were prepared on polycarbonate sheets by air brushing layers of dispersions and pressing the films. We characterized the films for hydrolytic degradation, electrical conductivity, cell proliferation and neurite extension. The co-polymers were sufficient to carry out electrical stimulation of cells without the requirement of a metallic conductor underneath the co-polymer film. In vitro electrical stimulation of PPy-PCL significantly increased the number of PC12 cells bearing neurites compared to unstimulated PPy-PCL. For in vivo experiments, the PPy co-polymers were coated onto the inner walls of nerve guidance channels (NGCs) made of the commercially available non-conducting biodegradable polymer poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHB-HV). The NGCs were implanted in a 10 mm defect made in the sciatic nerve of rats, and harvested after 8 weeks. Histological staining showed axonal growth. The studies indicated that these new conducting degradable biomaterials have good biocompatibility and support proliferation and growth of PC12 cells in vitro (with and without electrical stimulation) and neurons in vivo (without electrical stimulation).

  20. Evaluation of non-thermal effects of electricity on anthocyanin degradation during ohmic heating of jaboticaba (Myrciaria cauliflora) juice.

    PubMed

    Mercali, Giovana Domeneghini; Gurak, Poliana Deyse; Schmitz, Frederico; Marczak, Ligia Damasceno Ferreira

    2015-03-15

    This study investigated the non-thermal effects of electricity on anthocyanin degradation during ohmic heating of jaboticaba juice. For this, temperature profiles during conventional and ohmic heating processes were matched, and the degradation kinetics of anthocyanins were compared at temperatures ranging from 70 to 90°C. The monomeric anthocyanin content was quantified by UV-Visible spectroscopy using the pH-differential method. Anthocyanin degradation was fitted to a first-order model. The rate constants ranged from 1.7 to 7.5 × 10(-3)min(-1) and from 1.8 to 7.6 × 10(-3)min(-1) for ohmic and conventional heating, respectively. The analysis of variance (α=0.05) showed no significant differences between rate constants of the ohmic and conventional heating at the same temperatures. All kinetic and thermodynamic parameters evaluated showed similar values for both technologies. These results indicate that the presence of the oscillating electric field did not affect the degradation rates of anthocyanins during ohmic heating.

  1. Microbial surface displayed enzymes based biofuel cell utilizing degradation products of lignocellulosic biomass for direct electrical energy.

    PubMed

    Fan, Shuqin; Hou, Chuantao; Liang, Bo; Feng, Ruirui; Liu, Aihua

    2015-09-01

    In this work, a bacterial surface displaying enzyme based two-compartment biofuel cell for the direct electrical energy conversion from degradation products of lignocellulosic biomass is reported. Considering that the main degradation products of the lignocellulose are glucose and xylose, xylose dehydrogenase (XDH) displayed bacteria (XDH-bacteria) and glucose dehydrogenase (GDH) displayed bacteria (GDH-bacteria) were used as anode catalysts in anode chamber with methylene blue as electron transfer mediator. While the cathode chamber was constructed with laccase/multi-walled-carbon nanotube/glassy-carbon-electrode. XDH-bacteria exhibited 1.75 times higher catalytic efficiency than GDH-bacteria. This assembled enzymatic fuel cell exhibited a high open-circuit potential of 0.80 V, acceptable stability and energy conversion efficiency. Moreover, the maximum power density of the cell could reach 53 μW cm(-2) when fueled with degradation products of corn stalk. Thus, this finding holds great potential to directly convert degradation products of biomass into electrical energy.

  2. Optimal economy-based battery degradation management dynamics for fuel-cell plug-in hybrid electric vehicles

    NASA Astrophysics Data System (ADS)

    Martel, François; Kelouwani, Sousso; Dubé, Yves; Agbossou, Kodjo

    2015-01-01

    This work analyses the economical dynamics of an optimized battery degradation management strategy intended for plug-in hybrid electric vehicles (PHEVs) with consideration given to low-cost technologies, such as lead-acid batteries. The optimal management algorithm described herein is based on discrete dynamic programming theory (DDP) and was designed for the purpose of PHEV battery degradation management; its operation relies on simulation models using data obtained experimentally on a physical PHEV platform. These tools are first used to define an optimal management strategy according to the economical weights of PHEV battery degradation and the secondary energy carriers spent to manage its deleterious effects. We then conduct a sensitivity study of the proposed optimization process to the fluctuating economic parameters associated with the fuel and energy costs involved in the degradation management process. Results demonstrate the influence of each parameter on the process's response, including daily total operating costs and expected battery lifetime, as well as establish boundaries for useful application of the method; in addition, they provide a case for the relevance of inexpensive battery technologies, such as lead-acid batteries, for economy-centric PHEV applications where battery degradation is a major concern.

  3. Electricity generation and pollutant degradation using a novel biocathode coupled photoelectrochemical cell.

    PubMed

    Du, Yue; Feng, Yujie; Qu, Youpeng; Liu, Jia; Ren, Nanqi; Liu, Hong

    2014-07-01

    The photoelectrochemical cell (PEC) is a promising tool for the degradation of organic pollutants and simultaneous electricity recovery, however, current cathode catalysts suffer from high costs and short service lives. Herein, we present a novel biocathode coupled PEC (Bio-PEC) integrating the advantages of photocatalytic anode and biocathode. Electrochemical anodized TiO2 nanotube arrays fabricated on Ti substrate were used as Bio-PEC anodes. Field-emission scanning electron microscope images revealed that the well-aligned TiO2 nanotubes had inner diameters of 60-100 nm and wall-thicknesses of about 5 nm. Linear sweep voltammetry presented the pronounced photocurrent output (325 μA/cm(2)) under xenon illumination, compared with that under dark conditions. Comparing studies were carried out between the Bio-PEC and PECs with Pt/C cathodes. The results showed that the performance of Pt/C cathodes was closely related with the structure and Pt/C loading amounts of cathodes, while the Bio-PEC achieved similar methyl orange (MO) decoloration rate (0.0120 min(-1)) and maximum power density (211.32 mW/m(2)) to the brush cathode PEC with 50 mg Pt/C loading (Brush-PEC, 50 mg). The fill factors of Bio-PEC and Brush-PEC (50 mg) were 39.87% and 43.06%, respectively. The charge transfer resistance of biocathode was 13.10 Ω, larger than the brush cathode with 50 mg Pt/C (10.68 Ω), but smaller than the brush cathode with 35 mg Pt/C (18.35 Ω), indicating the comparable catalytic activity with Pt/C catalyst. The biocathode was more dependent on the nutrient diffusion, such as nitrogen and inorganic carbon, thus resulting in relatively higher diffusion resistance compared to the brush cathode with 50 mg Pt/C loading that yielded similar MO removal and power output. Considering the performance and cost of PEC system, the biocathode was a promising alternative for the Pt/C catalyst.

  4. Roadmap to MaRIE March 2015

    SciTech Connect

    Barnes, Cris William

    2015-03-30

    Los Alamos National Laboratory’s proposed MaRIE facility is slated to introduce the world’s highest energy hard x-ray free electron laser (XFEL). As the light source for the Matter-Radiation Interactions in Extremes experimental facility (MaRIE), the 42-keV XFEL, with bursts of x-ray pulses at gigahertz repetition for studying fast dynamical processes, will help accelerate discovery and design of the advanced materials needed to meet 21st-century national security and energy security challenges. Yet the science of free-electron lasers has a long and distinguished history at Los Alamos National Laboratory (LANL), where for nearly four decades Los Alamos scientists have been performing research, design, development, and collaboration work in FEL science. The work at Los Alamos has evolved from low-gain amplifier and oscillator FEL development to highbrightness photoinjector development, and later, self-amplified spontaneous emission (SASE) and high-gain amplifier FEL development.

  5. Degradation of the electrical characteristics of MOS structures with erbium, gadolinium, and dysprosium oxides under the effect of an electric field

    SciTech Connect

    Shalimova, M. B. Sachuk, N. V.

    2015-08-15

    The degradation of the characteristics of silicon metal-oxide-semiconductor (MOS) structures with oxides of rare-earth elements under the effect of electric fields with intensities of 0.1–4 MV/cm during the course of electroforming is studied. A specific feature of electroforming consists in the possibility of multiple switching of the structures from the insulating state to the low-resistivity one and back. The temporal characteristics of the degradation of MOS structures during the course of electroforming are exponential. The current-voltage characteristics follow the power law in the range of 0.2–3 V; the effect of an electric field brings about a variation in the distribution of the energy density of traps responsible for currents limited by space charge. It is established that multiple cycles of electroforming lead to an increase in the density of surface states at the Si-oxide interface and to a variation in the energy position of the trap levels, which affects the charge state of the traps.

  6. Ejecta of the Ries Crater, Germany

    NASA Technical Reports Server (NTRS)

    Horz, F.

    1982-01-01

    Attention is given to the light which may be shed by the ejecta surrounding the 26-km diameter Ries Crater in West Germany on the Cretaceous-Tertiary Boundary Event. Moldavites represent early high speed ejecta originating at the projectile-target interface. Bunte breccia reflects the major excavation and ejection phase, comprising more than 90 percent of all ejecta beyond the rim crest. Suevite is deposited last, and is derived from the deepest target stratum. Using various scaling laws that relate the bolide's kinetic energy to crater geometry or volume, and assuming a 25 km/sec impact velocity, a 1-2 km projectile diameter is obtained for a stony object. Geochemical studies reveal that projectile dissemination is heterogeneous, and that maximum extraterrestrial contamination modeled as a C1 chondrite is 0.004 wt pct. Observations from this and other terrestrial craters show that tektites and microtectites provide the sole evidence for widespread impact deposits.

  7. Electric-Field-Induced Degradation of Methylammonium Lead Iodide Perovskite Solar Cells.

    PubMed

    Bae, Soohyun; Kim, Seongtak; Lee, Sang-Won; Cho, Kyung Jin; Park, Sungeun; Lee, Seunghun; Kang, Yoonmook; Lee, Hae-Seok; Kim, Donghwan

    2016-08-18

    Perovskite solar cells have great potential for high efficiency generation but are subject to the impact of external environmental conditions such as humidity, UV and sun light, temperature, and electric fields. The long-term stability of perovskite solar cells is an important issue for their commercialization. Various studies on the stability of perovskite solar cells are currently being performed; however, the stability related to electric fields is rarely discussed. Here the electrical stability of perovskite solar cells is studied. Ion migration is confirmed using the temperature-dependent dark current decay. Changes in the power conversion efficiency according to the amount of the external bias are measured in the dark, and a significant drop is observed only at an applied voltage greater than 0.8 V. We demonstrate that perovskite solar cells are stable under an electric field up to the operating voltage.

  8. Enhanced hexadecane degradation and low biomass production by Aspergillus niger exposed to an electric current in a model system.

    PubMed

    Velasco-Alvarez, Nancy; González, Ignacio; Damian-Matsumura, Pablo; Gutiérrez-Rojas, Mariano

    2011-01-01

    The effects of an electric current on growth and hexadecane (HXD) degradation by Aspergillus niger growth were determined. A 450-mL electrochemical cell with titanium ruthenium-oxide coated electrodes and packed with 15 g of perlite (inert biomass support) was inoculated with A. niger (2.0×10(7) spores (g of dry inert support)(-1)) and incubated for 12 days (30 °C; constant ventilation). 4.5 days after starting culture a current of 0.42 mA cm(-2) was applied for 24h. The current reduced (52±11%) growth of the culture as compared to that of a culture not exposed to current. However, HXD degradation was 96±1.4% after 8 days whereas it was 81±1.2% after 12 days in control cultures. Carbon balances of cultures not exposed to current suggested an assimilative metabolism, but a non-assimilative metabolism when the current was applied. This change can be related to an increase in total ATP content. The study contributes to the knowledge on the effects of current on the mycelial growth phase of A. niger, and suggests the possibility of manipulating the metabolism of this organism with electric current.

  9. Modulated and ordered defect structures in electrically degraded Ni-BaTiO3 multilayer ceramic capacitors

    NASA Astrophysics Data System (ADS)

    Yang, G. Y.; Dickey, E. C.; Randall, C. A.; Randall, M. S.; Mann, L. A.

    2003-11-01

    Structural defects formed on {111} planes of BaTiO3 during the degradation of high performance multilayer Ni-BaTiO3 X7R ceramic capacitors are studied using transmission electron microscopy and electron energy loss spectroscopy (EELS). Regular pseudocubic barium titanate grains are present in as-produced (virginal) base-metal electrode capacitors. However, there is a coexistence of regular, modulated, and long-range ordered structures in intentionally electrically degraded devices. The EELS analysis demonstrates that the concentration of oxygen vacancies in barium titanate with modulated or ordered structures is higher than that in the regular perovskite grains. The clustering or accumulation of oxygen vacancies in the structural framework of BaTiO3 gives rise to the formation of new metastable structures. These observations are consistent with earlier models for degradation, but demonstrate that the details of the process may be more complex than originally assumed. Here we introduce new details on the nature of the reduction process and the manner in which the lattice accommodates the enhanced oxygen vacancy concentration towards the failed regions of the capacitors and in the vicinity of the "blocking" cathodic electrodes.

  10. Statistical analysis for understanding and predicting battery degradations in real-life electric vehicle use

    NASA Astrophysics Data System (ADS)

    Barré, Anthony; Suard, Frédéric; Gérard, Mathias; Montaru, Maxime; Riu, Delphine

    2014-01-01

    This paper describes the statistical analysis of recorded data parameters of electrical battery ageing during electric vehicle use. These data permit traditional battery ageing investigation based on the evolution of the capacity fade and resistance raise. The measured variables are examined in order to explain the correlation between battery ageing and operating conditions during experiments. Such study enables us to identify the main ageing factors. Then, detailed statistical dependency explorations present the responsible factors on battery ageing phenomena. Predictive battery ageing models are built from this approach. Thereby results demonstrate and quantify a relationship between variables and battery ageing global observations, and also allow accurate battery ageing diagnosis through predictive models.

  11. dc-Electrical Degradation of the BT-Based Material for Multilayer Ceramic Capacitor with Ni internal Electrode: Impedance Analysis and Microstructure

    NASA Astrophysics Data System (ADS)

    Chazono, Hirokazu; Kishi, Hiroshi

    2001-09-01

    The impedance of a BaTiO3 (BT)-based multilayer ceramic capacitor with a nickel internal electrode (Ni-MLCC) was investigated by measuring the frequency domain at various temperatures. All the obtained impedance data could be successfully fitted to a 4-RC section electrical equivalent network. The 4-RC section electrical equivalent network was successfully correlated to the microstructure: the core, the shell, the grain boundary, and the ceramic/internal electrode interface regions. Based on this electrical equivalent network, the electrical properties including the Curie-Weiss law, the current-voltage characteristics, and dc electrical degradation, were well explained. A model for the degradation behavior for BT-based Ni-MLCC with thin active layer thickness was proposed.

  12. Relation between degradation of electrical parameters of MOS transistors by hot carrier injection and their drift due to radiation for a new rad-hardened ACMOS technology

    NASA Astrophysics Data System (ADS)

    Frapreau, I.; Gagnard, X.

    2002-12-01

    Space environment induces degradations, which affect electrical performances of MOS transistors in satellites. It is very interesting to prevent such degradations, to be more competitive and to mainly satisfy customers in the best conditions. But the tests by ionizing radiations are long and expensive. That's why we would like to predict the effects of radiation by using tests with hot-carrier injection. Indeed the degradations induced with hot-carrier and radiations effects are similar. Oxide is damaged by charge trapping and interface states generation. Electrical parameters such as threshold voltage, linear current and transconductance are affected. Our study consists to find a correlation between the degradations of MOS transistors induced with hot-carrier and their damages due to gamma radiation environment.

  13. The use of acoustic cues for phonetic identification: Effects of spectral degradation and electric hearinga)

    PubMed Central

    Winn, Matthew B.; Chatterjee, Monita; Idsardi, William J.

    2012-01-01

    Although some cochlear implant (CI) listeners can show good word recognition accuracy, it is not clear how they perceive and use the various acoustic cues that contribute to phonetic perceptions. In this study, the use of acoustic cues was assessed for normal-hearing (NH) listeners in optimal and spectrally degraded conditions, and also for CI listeners. Two experiments tested the tense/lax vowel contrast (varying in formant structure, vowel-inherent spectral change, and vowel duration) and the word-final fricative voicing contrast (varying in F1 transition, vowel duration, consonant duration, and consonant voicing). Identification results were modeled using mixed-effects logistic regression. These experiments suggested that under spectrally-degraded conditions, NH listeners decrease their use of formant cues and increase their use of durational cues. Compared to NH listeners, CI listeners showed decreased use of spectral cues like formant structure and formant change and consonant voicing, and showed greater use of durational cues (especially for the fricative contrast). The results suggest that although NH and CI listeners may show similar accuracy on basic tests of word, phoneme or feature recognition, they may be using different perceptual strategies in the process. PMID:22352517

  14. Improved fuel cell and electrode designs for producing electricity from microbial degradation.

    PubMed

    Park, Doo Hyun; Zeikus, J Gregory

    2003-02-05

    A new one-compartment fuel cell was composed of a rubber bunged bottle with a center-inserted anode and a window-mounted cathode containing an internal, proton-permeable porcelain layer. This fuel cell design was less expensive and more practical than the conventional two-compartment system, which requires aeration and a ferricyanide solution in the cathode compartment. Three new electrodes containing bound electron mediators including a Mn(4+)-graphite anode, a neutral red (NR) covalently linked woven graphite anode, and an Fe(3+)-graphite cathode were developed that greatly enhanced electrical energy production (i.e., microbial electron transfer) over conventional graphite electrodes. The potentials of these electrodes measured by cyclic voltametry at pH 7.0 were (in volts): +0.493 (Fe(3+)-graphite); +0.15 (Mn(4+)-graphite); and -0.53 (NR-woven graphite). The maximal electrical productivities obtained with sewage sludge as the biocatalyst and using a Mn(4+)-graphite anode and a Fe(3+)-graphite cathode were 14 mA current, 0.45 V potential, 1,750 mA/m(2) current density, and 788 mW/m(2) of power density. With Escherichia coli as the biocatalyst and using a Mn(4+)-graphite anode and a Fe(3+)-graphite cathode, the maximal electrical productivities obtained were 2.6 mA current, 0.28 V potential, 325 mA/m(2) current density, and 91 mW/m(2) of power density. These results show that the amount of electrical energy produced by microbial fuel cells can be increased 1,000-fold by incorporating electron mediators into graphite electrodes. These results also imply that sewage sludge may contain unique electrophilic microbes that transfer electrons more readily than E. coli and that microbial fuel cells using the new Mn(4+)-graphite anode and Fe(3+)-graphite cathode may have commercial utility for producing low amounts of electrical power needed in remote locations.

  15. MaRIE theory, modeling and computation roadmap executive summary

    SciTech Connect

    Lookman, Turab

    2010-01-01

    The confluence of MaRIE (Matter-Radiation Interactions in Extreme) and extreme (exascale) computing timelines offers a unique opportunity in co-designing the elements of materials discovery, with theory and high performance computing, itself co-designed by constrained optimization of hardware and software, and experiments. MaRIE's theory, modeling, and computation (TMC) roadmap efforts have paralleled 'MaRIE First Experiments' science activities in the areas of materials dynamics, irradiated materials and complex functional materials in extreme conditions. The documents that follow this executive summary describe in detail for each of these areas the current state of the art, the gaps that exist and the road map to MaRIE and beyond. Here we integrate the various elements to articulate an overarching theme related to the role and consequences of heterogeneities which manifest as competing states in a complex energy landscape. MaRIE experiments will locate, measure and follow the dynamical evolution of these heterogeneities. Our TMC vision spans the various pillar science and highlights the key theoretical and experimental challenges. We also present a theory, modeling and computation roadmap of the path to and beyond MaRIE in each of the science areas.

  16. Electrical characterization and analysis of the degradation of electrode Schottky barriers in BaTiO3 dielectric materials due to hydrogen exposure

    NASA Astrophysics Data System (ADS)

    Heidary, Damoon Sohrabi Baba; Qu, Weiguo; Randall, Clive A.

    2015-03-01

    Hydrogen gas creates a highly damaging environment that degrades electrical properties in oxide based dielectrics and piezoelectrics. In this study, the degradation resistivity due to hydrogen gas in a barium titanate X7R dielectric is designed and processed for base metal electrode capacitors. The present paper is devoted to I-V measurements and the loss of resistivity in the electrode Schottky barriers. The DC degradation and asymmetries noted in I-V forward and reverse biasing conditions were assumed to be hydrogen ion interstitials, locally creating donor substitutions. Thermionic and field emission conductivity mechanisms are applied to model the I-V data; the conductivity is controlled by the Schottky barrier heights and hydrogen ions localizing at the interfaces. Finally, a mechanism was proposed for resistivity degradation due to exposure to hydrogen gas. The proposed mechanism predicts the degradation should be reversible, and its validity was examined by recovery tests.

  17. Second Life for Electric Vehicle Batteries: Answering Questions on Battery Degradation and Value

    SciTech Connect

    Neubauer, J. S.; Wood, E.; Pesaran, A.

    2015-05-04

    Battery second use – putting used plug-in electric vehicle (PEV) batteries into secondary service following their automotive tenure – has been proposed as a means to decrease the cost of PEVs while providing low cost energy storage to other fields (e.g. electric utility markets). To understand the value of used automotive batteries, however, we must first answer several key questions related to National Renewable Energy Laboratory (NREL) has developed a methodology and the requisite tools to answer these questions, including NREL’s Battery Lifetime Simulation Tool (BLAST). Herein we introduce these methods and tools, and demonstrate their application. We have found that capacity fade from automotive use has a much larger impact on second use value than resistance growth. Where capacity loss is driven by calendar effects more than cycling effects, average battery temperature during automotive service – which is often driven by climate – is found to be the single factor with the largest effect on remaining value. Installing hardware and software capabilities onboard the vehicle that can both infer remaining battery capacity from in-situ measurements, as well as track average battery temperature over time, will thereby facilitate the second use of automotive batteries.

  18. Modeling of asymmetric degradation based on a non-uniform electric field and temperature in amorphous In–Ga–Zn–O thin film transistors

    NASA Astrophysics Data System (ADS)

    In Kim, Jong; Jeong, Chan-Yong; Kwon, Hyuck-In; Jung, Keum Dong; Park, Mun Soo; Kim, Ki Hwan; Seo, Mi Seon; Lee, Jong-Ho

    2017-03-01

    We propose a new local degradation model based on a non-uniform increase in donor-like traps (DLTs) determined by distributions of an electric field and measured device temperature in amorphous In–Ga–Zn–O (a-IGZO) thin film transistors (TFTs). A systematic investigation of the degradation model reveals that vertical field-dependent DLTs are essential for modeling of measured asymmetric electrical characteristics between the source and drain after positive gate and drain bias stressing. An increased temperature due to self-heating is found to play a role in intensifying the asymmetric degradation. From the individual simulation of measured transfer curves at different stress times, the model parameters and an asymmetry index as a function of stress time are extracted. It is expected that this novel methodology will provide new insight into asymmetric degradation and be utilized to predict the influence of electric field and heat on degradation under various bias-stress conditions in a-IGZO TFTs.

  19. Explore various co-substrates for simultaneous electricity generation and Congo red degradation in air-cathode single-chamber microbial fuel cell.

    PubMed

    Cao, Yunqing; Hu, Yongyou; Sun, Jian; Hou, Bin

    2010-08-01

    Microbial fuel cell (MFC) holds a great promise to harvest electricity directly from a wide range of ready degradable organic matters and enhance degradation of some recalcitrant contaminants. Glucose, acetate sodium and ethanol were separately examined as co-substrates for simultaneous bioelectricity generation and Congo red degradation in a proton exchange membrane (PEM) air-cathode single-chamber MFC. The batch test results showed that more than 98% decolorization at the dye concentration of 300 mg/L were achieved within 36 h for all tested co-substrates during electricity generation. The decolorization rate was different with the co-substrates used. The fastest decolorization rate was achieved with glucose followed by ethanol and sodium acetate. Accumulated intermediates were observed during Congo red degradation which was demonstrated by UV-Visible spectra and high performance liquid chromatography (HPLC). Electricity generation was sustained and not significantly affected by the Congo red degradation. Glucose, acetate sodium and ethanol produced maximum power densities of 103 mW/m(2), 85.9 mW/m(2) and 63.2 mW/m(2), respectively, and the maximum voltage output decreased by only 7% to 15%. Our results demonstrated the feasibility of using various co-substrates for simultaneous decolorization of Congo red and bioelectricity generation in the MFC and showed that glucose was the preferred co-substrate.

  20. Optimization and application of TiO₂/Ti-Pt photo fuel cell (PFC) to effectively generate electricity and degrade organic pollutants simultaneously.

    PubMed

    Li, Kan; Zhang, Hongbo; Tang, Tiantian; Xu, Yunlan; Ying, Diwen; Wang, Yalin; Jia, Jinping

    2014-10-01

    A TiO2/Ti-Pt photo fuel cell (PFC) was established to generate electricity and degrade organic pollutants simultaneously. The electricity generation was optimized through investigation the influences of photoanode calcination temperature and dissolve oxygen on the resistances existing in PFC. TiO2 light quantum yield was also improved in PFC which resulted in a higher PC degradation efficiency. Two kinds of real textile wastewaters were also employed in this PFC system, 62.4% and 50.0% Coulombic efficiency were obtained for 8 h treatment. These refractory wastewaters with high salinity may become good fuels in PFC because a) TiO2 has no selectivity and can degrade nearly any organic substance, b) no more electrolyte is needed due to the high salinity, c) the energy in wastes can be recovered to generate electricity. The electricity generated by the PFC was further applied on a TiO2/Ti rotating disk photoelectrocatalytic reactor. A bias voltage between 0.6 and 0.75 V could be applied and the PC degradation efficiency was significantly improved. This result was similar with that obtained by a 0.7 V DC power.

  1. Preparation of C60(O)n-ZnO nanocomposite under electric furnace and photocatalytic degradation of organic dyes.

    PubMed

    Cho, Bum Hwi; Oh, Youn Jun; Mun, Sang Mi; Ko, Weon Bae

    2012-07-01

    Zinc oxide (ZnO) nanoparticles were synthesized sonochemically by applying ultrasonic irradiation to a mixed aqueous-alcoholic solution of zinc nitrate with sodium hydroxide at room temperature. The morphology and optical properties of the ZnO nanoparticles were examined by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and UV-vis spectroscopy. The C60(O)n nanoparticles were synthesized by heating a mixture of C60 and 3-chloroperoxybenzoic acid in a benzene solvent under the reflux system. The heated C60(O)n-ZnO nanocomposite was synthesized in an electric furnace at 700 degrees C for two hours. The heated C60(O)n-ZnO nanocomposite was characterized by XRD, SEM, and TEM, and examined as a catalyst in the photocatalytic degradation of organic dyes by UV-vis spectroscopy. The photocatalytic effect of the heated C60(O)n-ZnO nanocomposite was evaluated by a comparison with that of unheated C60(O)n nanoparticles, heated C60(O)n nanoparticles, and unheated C60(O)n-ZnO in organic dyes, such as methylene blue (MB), methyl orange (MO), and rhodamine B (RhB) under ultraviolet light at 365 nm.

  2. Synthesis of [60]fullerene-ZnO nanocomposite under electric furnace and photocatalytic degradation of organic dyes.

    PubMed

    Hong, Sung Kyu; Lee, Jeong Ho; Ko, Weon Bae

    2011-07-01

    Zinc oxide (ZnO) nanoparticles were synthesized by a reaction between an aqueous-alcoholic solution of zinc nitrate and sodium hydroxide under ultrasonic irradiation at room temperature. The morphology, optical properties of the ZnO nanoparticles were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-vis spectroscopy. The [60]fullerene and zinc oxide nanocomposite were synthesized in an electric furnace at 700 degrees C for two hours. The [60]fullerene-ZnO nanocomposite was characterized by XRD, SEM and TEM. In addition, the [60]fullerene-ZnO nanocomposite was investigated as a catalyst in the photocatalytic degradation of organic dyes using UV-vis spectroscopy. The photocatalytic activity of the [60]fullerene-ZnO nanocomposite was compared with that of ZnO nanoparticles, heated ZnO nanoparticles after synthesis, pure [60]fullerene, and heated pure [60]fullerene in organic dyes such as methylene blue (MB), methyl orange (MO), and rhodamine B (RhB) under ultraviolet light at 254 nm.

  3. Photocatalytic and photoelectrocatalytic degradation of the drug omeprazole on nanocrystalline titania films in alkaline media: Effect of applied electrical bias on degradation and transformation products.

    PubMed

    Tantis, Iosif; Bousiakou, Leda; Frontistis, Zacharias; Mantzavinos, Dionissios; Konstantinou, Ioannis; Antonopoulou, Maria; Karikas, George-Albert; Lianos, Panagiotis

    2015-08-30

    Photocatalytic and photoelectrocatalytic degradation of the drug omeprazole has been studied in the presence of nanocrystalline titania films supported on glass slides or transparent FTO electrodes in alkaline environment. Its photocatalytic degradation rate was assessed by its UV absorbance and by HPLC, while its transformation products were analyzed by HR-LC-MS. Based on UV absorbance, omeprazole can be photocatalytically degraded at an average rate of 6.7×10(-4)min(-1) under low intensity UVA irradiation of 1.5mWcm(-2) in the presence of a nanoparticulate titania film. This corresponds to degradation of 1.4mg of omeprazole per gram of the photocatalyst per liter of solution per hour. The photodegradation rate can be accelerated in a photoelectrochemical cell by applying a forward bias. In this case, the maximum rate reached under the present conditions was 11.6×10(-4)min(-1) by applying a forward bias of +0.6V vs. Ag/AgCl. Four major transformation products were successfully identified and their profiles were followed by HR-LC-MS. The major degradation path includes the scission of the sulfoxide bridge into the corresponding pyridine and benzimidazole ring derivates and this is accompanied by the release of sulfate anions in the reaction mixture.

  4. Electricity

    SciTech Connect

    Sims, B.

    1983-01-01

    Historical aspects of electricity are reviewed with individual articles on hydroelectric dams, coal-burning power plants, nuclear power plants, electricity distribution, and the energy future. A glossary is included. (PSB)

  5. Resources in Education (RIE). Volume 37, Number 8.

    ERIC Educational Resources Information Center

    Resources in Education, 2002

    2002-01-01

    "Resources in Education" (RIE), the document portion of the ERIC database, announces (catalogs, indexes, abstracts) documents of interest to the educational community, including researchers, teachers, students, school board members, school administrators, counselors, parents, etc. It provides for electronic searching by Subject, Personal…

  6. Resources in Education (RIE). Volume 37, Number 12.

    ERIC Educational Resources Information Center

    Resources in Education, 2002

    2002-01-01

    "Resources in Education" (RIE), the document portion of the ERIC database, announces (catalogs, indexes, abstracts) documents of interest to the educational community, including researchers, teachers, students, school board members, school administrators, counselors, parents, etc. It provides for electronic searching by Subject, Personal…

  7. Resources in Education (RIE). Volume 37, Number 10.

    ERIC Educational Resources Information Center

    Resources in Education, 2002

    2002-01-01

    "Resources in Education" (RIE), the document portion of the ERIC database, announces (catalogs, indexes, abstracts) documents of interest to the educational community, including researchers, teachers, students, school board members, school administrators, counselors, parents, etc. It provides for electronic searching by Subject, Personal…

  8. Resources in Education (RIE). Volume 37, Number 11.

    ERIC Educational Resources Information Center

    Resources in Education, 2002

    2002-01-01

    "Resources in Education" (RIE), the document portion of the ERIC database, announces (catalogs, indexes, abstracts) documents of interest to the educational community, including researchers, teachers, students, school board members, school administrators, counselors, parents, etc. It provides for electronic searching by Subject, Personal…

  9. Resources in Education (RIE). Volume 37, Number 9.

    ERIC Educational Resources Information Center

    Resources in Education, 2002

    2002-01-01

    "Resources in Education" (RIE), the document portion of the ERIC database, announces (catalogs, indexes, abstracts) documents of interest to the educational community, including researchers, teachers, students, school board members, school administrators, counselors, parents, etc. It provides for electronic searching by Subject, Personal…

  10. Degradation mechanisms of carbon-based electrocatalyst support materials and development of an advanced support based on electrically conducting diamond

    NASA Astrophysics Data System (ADS)

    Fischer, Anne Elizabeth

    2005-11-01

    In this dissertation, the degradation mechanisms of sp 2-bonded carbon electrocatalyst supports were studied under potential and temperature conditions relevant to the polymer electrolyte membrane fuel cell (PEMFC). In addition, an alternative support was fabricated in two forms: electrically conducting diamond powder and paper to overcome current material stability issues in the PEMFC. Two structurally well-characterized sp2-bonded carbon powders, graphite (structurally well-ordered) and glassy carbon (GC, structurally disordered) were studied under potentiostatic polarization from 1.0 to 1.6 V vs. Ag/AgCl at 25, 50, and 80°C. Characterization of the surface oxidation and microstructural changes (i.e., increase in the exposed edge plane density) provided evidence for the so-called order/disorder mechanism where structurally disordered carbons corrode more severely because of oxidation and gasification of the exposed edge plane. Microstructural changes for graphite were heterogeneously distributed across the electrode surface. This is indicative of a nucleation and growth process, where disordered regions and defects serve as active sites for electrochemical corrosion, while other, more structurally ordered regions do not corrode. Preliminary results for a high-surface-area carbon black, Vulcan XC-72, are presented that show changes in the surface oxide content and also discuss the effect of polarization potential on Pt activity. The physical and electrochemical properties of two commercial boron-doped diamond thin-film electrodes were compared with microcrystalline and nanocrystalline boron-doped diamond thin film deposited in our laboratory. The electrochemical response for Fe(CN)63-/4-, Ru(NH3)6 3+/2+, IrCl62-/3-, 4-methylcatechol, and Fe3+/2+ was quite reproducible from electrode type-to-type and from film-to-film for a given type. DeltaEp, ipox, and ip red values for Fe(CN)63-/4-, Ru(NH 3)63+/2+ on all electrodes were relatively unaffected by pH. Electrically

  11. DC Electrical Conductivity Retention, Optical Properties and Ammonia Sensing Analysis of Naturally Degraded CSA-Doped Graphene/polyaniline Composite Nanofibers Prepared with CTAB

    NASA Astrophysics Data System (ADS)

    Ghazali, Sayyed; Hossain, Muhammad M.; Khan, Abuzar; Khan, Mohd Y.; Hasan, Mudassir

    2017-01-01

    In this paper, we report surfactant-mediated synthesis of camphor sulfonic acid (CSA)-doped polyaniline/graphene (PANI/GN) composite nanofibers as an electrical conductor and excellent ammonia sensor. The synthesis was mediated by cetyltrimethylammonium bromide as surfactant. The as-synthesized composite nanofibers were characterized by Raman spectroscopy, scanning electron microscopy, tunneling electron microscopy, x-ray diffraction, diffused reflectance spectroscopy and differential scanning calorimetry. The electrical conductivity of the CSA-doped PANI/GN composite nanofibers was found to be remarkably enhanced as compared to the CSA-doped PANI. The boost in electronic conductivity could be attributed to an improved electronic interaction between CSA-doped PANI backbone and GN present in the composite system. The naturally degraded CSA-doped PANI/GN composite nanofibers showed a decrease in electrical conductivity but worked as a good ammonia sensor in open atmospheric conditions.

  12. Experimental Physical Sciences Vistas: MaRIE (draft)

    SciTech Connect

    Shlachter, Jack

    2010-09-08

    To achieve breakthrough scientific discoveries in the 21st century, a convergence and integration of world-leading experimental facilities and capabilities with theory, modeling, and simulation is necessary. In this issue of Experimental Physical Sciences Vistas, I am excited to present our plans for Los Alamos National Laboratory's future flagship experimental facility, MaRIE (Matter-Radiation Interactions in Extremes). MaRIE is a facility that will provide transformational understanding of matter in extreme conditions required to reduce or resolve key weapons performance uncertainties, develop the materials needed for advanced energy systems, and transform our ability to create materials by design. Our unique role in materials science starting with the Manhattan Project has positioned us well to develop a contemporary materials strategy pushing the frontiers of controlled functionality - the design and tailoring of a material for the unique demands of a specific application. Controlled functionality requires improvement in understanding of the structure and properties of materials in order to synthesize and process materials with unique characteristics. In the nuclear weapons program today, improving data and models to increase confidence in the stockpile can take years from concept to new knowledge. Our goal with MaRIE is to accelerate this process by enhancing predictive capability - the ability to compute a priori the observables of an experiment or test and pertinent confidence intervals using verified and validated simulation tools. It is a science-based approach that includes the use of advanced experimental tools, theoretical models, and multi-physics codes, simultaneously dealing with multiple aspects of physical operation of a system that are needed to develop an increasingly mature predictive capability. This same approach is needed to accelerate improvements to other systems such as nuclear reactors. MaRIE will be valuable to many national security

  13. Enhanced organic pollutants degradation and electricity production simultaneously via strengthening the radicals reaction in a novel Fenton-photocatalytic fuel cell system.

    PubMed

    Zhao, Kai; Zeng, Qingyi; Bai, Jing; Li, Jinhua; Xia, Ligang; Chen, Shuai; Zhou, Baoxue

    2017-01-01

    An enhanced result in organic pollutants degradation and simultaneous electricity production has been achieved by establishing a novel Fenton-photocatalytic fuel cell (Fenton-PFC) system in which TiO2 nanotube arrays (TNA) was designed as a photoanode and ferrous ions were added. The proposed Fenton-PFC system can expand the radical reaction for organic pollutants degradation from the surface of electrodes to the whole solution system due to a continuous photoelectric Fenton reaction without continually adding any external voltage and ferrous ions. The cyclic reactions between ferrous ions (Fe(2+)/Fe(3+)) and radicals and related species (HO, HO2, O2(-) and H2O2 etc.) can be achieved at electrodes surface via a self-bias voltage yielded by the PFC. More importantly, the proposed Fenton-PFC system has hardly any sludge due to an effective radical reaction using a small amount of ferrous ions. The degradation rate of refractory organics, such as methyl orange, methylene blue, congo red and tetracycline, increased from 34.99%, 43.75%, 40.58% and 34.40% (the traditional PFC without Fe(2+)) to 97.34%, 95.36%, 93.23% and 73.80% (the Fenton-PFC within Fe(2+)) respectively after 60 min operation. Meanwhile, the electricity generation is up to 1.21-2.04 times larger than the traditional PFC. The proposed Fenton-PFC system provides a more economical and efficient way for energy recovery and wastewater treatment.

  14. Insights into ultraviolet-induced electrical degradation of thermally grown SiO{sub 2}/4H-SiC(0001) interface

    SciTech Connect

    Ikeguchi, Daisuke; Hosoi, Takuji; Shimura, Takayoshi; Watanabe, Heiji; Nakano, Yuki; Nakamura, Takashi

    2014-01-06

    The harmful impact of ultraviolet (UV) light irradiation on thermally grown SiO{sub 2}/4H-SiC structures was investigated by means of electrical measurements of metal-oxide-semiconductor (MOS) capacitors. Unlike Si-based MOS devices, significant electrical degradation, such as positive flatband voltage (V{sub FB}) shift and hysteresis in the capacitance-voltage (C-V) curves of SiC-MOS capacitors was induced by UV irradiation with a low-pressure mercury lamp. The interfacial fixed charge density increased with UV-irradiation (22.6 mW/cm{sup 2} for 16 h) to 1.7 × 10{sup 12} cm{sup −2}, which was an order of magnitude larger than that of the as-grown SiO{sub 2}/SiC interface. A detailed study based on single wavelength solid-state UV lasers revealed that there was a threshold photon energy at around 5 eV and a moderate dependence of UV-induced degradation on temperature. These experimental findings imply that pre-existing inactive defects accumulated at the thermally grown SiO{sub 2}/SiC interface were transformed to active carrier traps with high-energy UV irradiation through transparent SiO{sub 2} layers.

  15. Impact of continuous and intermittent supply of electric assistance on high-strength 2,4-dichlorophenol (2,4-DCP) degradation in electro-microbial system.

    PubMed

    Cao, Zhanping; Zhang, Minghui; Zhang, Jingli; Zhang, Hongwei

    2016-07-01

    The high-strength 2,4-DCP, which exists in two states: dissolved and colloidal, was studied by a continuously electro-microbial system (CEMS) and an intermittently electro-microbial system (IEMS). The hydrolysis rate of colloidal 2,4-DCP in the IEMS without electric assistance was much higher than that in the CEMS. However, the degradation rate of the dissolved 2,4-DCP and the dissolved intermediates (2-chlorophenol and 4-chlorophenol) in the IEMS without electric assistance were much lower than that in the CEMS. By adjusting the intermittent operation mode, the degradation time of 2,4-DCP was shortened greatly. Microbial characteristics in the CEMS and the IEMS were different. The correlation analysis for the main factors affecting the hydrolysis was performed by SPSS, and it was found that the correlation coefficient (rp) was -0.912 for extracellular polymeric substances (EPS) content, 0.823 for zeta potential and 0.632 for relative hydrophobicity, respectively.

  16. Modeling, Simulation, and Control of a Solar Electric Propulsion Vehicle in Near-Earth Vicinity Including Solar Array Degradation

    NASA Technical Reports Server (NTRS)

    Witzberger, Kevin (Inventor); Hojnicki, Jeffery (Inventor); Manzella, David (Inventor)

    2016-01-01

    Modeling and control software that integrates the complexities of solar array models, a space environment, and an electric propulsion system into a rigid body vehicle simulation and control model is provided. A rigid body vehicle simulation of a solar electric propulsion (SEP) vehicle may be created using at least one solar array model, at least one model of a space environment, and at least one model of a SEP propulsion system. Power availability and thrust profiles may be determined based on the rigid body vehicle simulation as the SEP vehicle transitions from a low Earth orbit (LEO) to a higher orbit or trajectory. The power availability and thrust profiles may be displayed such that a user can use the displayed power availability and thrust profiles to determine design parameters for an SEP vehicle mission.

  17. Fractal Fragmentation triggered by meteor impact: The Ries Crater (Germany)

    NASA Astrophysics Data System (ADS)

    Paredes Marino, Joali; Perugini, Diego; Rossi, Stefano; Kueppers, Ulrich

    2015-04-01

    FRACTAL FRAGMENTATION TRIGGERED BY METEOR IMPACT: THE RIES CRATER (GERMANY) Joali Paredes (1), Stefano Rossi (1), Diego Perugini (1), Ulrich Kueppers (2) 1. Department of Physics and Geology, University of Perugia, Italy 2. Department of Earth and Environmental Sciences, University of Munich, Germany The Nördlinger Ries is a large circular depression in western Bavaria, Germany. The depression was caused by a meteor impact, which occurred about 14.3 million-14.5 million years ago. The original crater rim had an estimated diameter of 24 kilometers. Computer modeling of the impact event indicates that the impact or probably had diameters of about 1.5 kilometers and impacted the target area at an angle around 30 to 50 degrees from the surface in a west- southwest to east-northeast direction. The impact velocity is thought to have been about 20 km/s. The meteor impact generated extensive fragmentation of preexisting rocks. In addition, melting of these rocks also occurred. The impact melt was ejected at high speed provoking its extensive fragmentation. Quenched melt fragments are ubiquitous in the outcrops. Here we study melt fragment size distributions with the aim of understanding the style of melt fragmentation during ejection and to constrain the rheological properties of such melts. Digital images of suevite (i.e. the rock generated after deposition and diagenesis of ash and fragments produced by the meteor impact) were obtained using a high-resolution optical scanner. Successively, melt fragments were traced by image analysis and the images segmented in order to obtain binary images on which impact melt fragments are in black color, embedded on a white background. Hence, the size of fragments was determined by image analysis. Fractal fragmentation theory has been applied to fragment size distributions of melt fragments in the Ries crater. Results indicate that melt fragments follow fractal distributions indicating that fragmentation of melt generated by the

  18. Long-term assessment of economic plug-in hybrid electric vehicle battery lifetime degradation management through near optimal fuel cell load sharing

    NASA Astrophysics Data System (ADS)

    Martel, François; Dubé, Yves; Kelouwani, Sousso; Jaguemont, Joris; Agbossou, Kodjo

    2016-06-01

    This work evaluates the performance of a plug-in hybrid electric vehicle (PHEV) energy management process that relies on the active management of the degradation of its energy carriers - in this scenario, a lithium-ion battery pack and a polymer electrolyte membrane fuel cell (PEMFC) - to produce a near economically-optimal vehicle operating profile over its entire useful lifetime. This solution is obtained through experimentally-supported PHEV models exploited by an optimal discrete dynamic programming (DDP) algorithm designed to efficiently process vehicle usage cycles over an extended timescale. Our results demonstrate the economic and component lifetime gains afforded by our strategy when compared with alternative rule-based PHEV energy management benchmarks.

  19. RIES - Rijnland Internet Election System: A Cursory Study of Published Source Code

    NASA Astrophysics Data System (ADS)

    Gonggrijp, Rop; Hengeveld, Willem-Jan; Hotting, Eelco; Schmidt, Sebastian; Weidemann, Frederik

    The Rijnland Internet Election System (RIES) is a system designed for voting in public elections over the internet. A rather cursory scan of the source code to RIES showed a significant lack of security-awareness among the programmers which - among other things - appears to have left RIES vulnerable to near-trivial attacks. If it had not been for independent studies finding problems, RIES would have been used in the 2008 Water Board elections, possibly handling a million votes or more. While RIES was more extensively studied to find cryptographic shortcomings, our work shows that more down-to-earth secure design practices can be at least as important, and the aspects need to be examined much sooner than right before an election.

  20. Study of the electrical parameters degradation of GaAs sub-cells for triple junction space solar cells by computer simulation

    NASA Astrophysics Data System (ADS)

    Cappelletti, M. A.; Casas, G. A.; Morales, D. M.; Hasperue, W.; Blancá, E. L. Peltzer y.

    2016-11-01

    In this paper, a theoretical study of the electrical parameters degradation of different n-type GaAs sub-cells for InGaP/GaAs/Ge triple junction solar cells irradiated with 1 and 5 MeV electrons has been performed by means of computer simulation. Effects of base carrier concentration upon the maximum power point, short-circuit current, open circuit voltage, diffusion current, recombination current and series resistance of these devices have been researched using the displacement damage dose method, the one-dimensional PC1D device modeling program and a home-made numerical code based on genetic algorithms. The radiative recombination lifetime, damage constant for minority-carrier lifetime and carrier removal rate models for GaAs sub-cells have been used in the simulations. An analytical model has been proposed, which is useful to describe the radiation-induced degradation of diffusion current, recombination current and series resistance. Results obtained in this work can be used to predict the radiation resistance of solar cells over a wide range of energies.

  1. Magnetic Mn substituted cobalt zinc ferrite systems: Structural, electrical and magnetic properties and their role in photo-catalytic degradation of methyl orange azo dye

    NASA Astrophysics Data System (ADS)

    Bhukal, Santosh; Bansal, S.; Singhal, Sonal

    2014-07-01

    The present work focuses on the effect of replacement of Fe3+ ions by the Mn3+ ions in cobalt zinc ferrites (Co0.6Zn0.4MnxFe2-xO4 (0.2, 0.4, 0.6, 0.8 and 1.0) on the structural, magnetic, electrical and catalytic properties. Powder X-ray diffraction studies confirmed that all the samples possessed cubic spinel structure with Fd-3m space groups. The saturation magnetization was found to decrease with increase in Mn3+ ions concentration. The drift mobility of all compositions was found to decrease with increase in temperature which could be attributed to the semiconductor nature of nanoferrites. The photo-catalytic activity of all the nanoferrites was evaluated by the degradation of methyl orange dye and it was observed that the degradation of methyl orange dye was enhanced with increase in Mn3+ ions concentration from 0.2 to 1.0. This might be due to the octahedral site preference and higher redox potential of manganese ion as compared those of iron.

  2. Analysis of organic compounds' degradation and electricity generation in anaerobic fluidized bed microbial fuel cell for coking wastewater treatment.

    PubMed

    Liu, Xinmin; Wu, Jianjun; Guo, Qingjie

    2017-02-22

    A single-chambered packing-type anaerobic fluidized microbial fuel cell (AFBMFC) with coking wastewater (CWW) as fuel was built to treat CWW, which not only has high treating efficiency, but also can convert organic matter in wastewater into electricity. AFBMFC was constructed by using anaerobic sludge that was domesticated as inoculation sludge, which was used to biochemically treat CWW. The organic compounds in CWW were extracted by liquid-liquid extraction step by step every day. The extraction phase was concentrated by a rotary evaporator and a nitrogen sweeping device and was analyzed by GC-MS. And the electricity-generation performances of AFBMFC were investigated. The results show that the composition of CWW was complicated, which mainly contains hydrocarbons, phenols, nitrogenous organic compounds, alcohols and aldehydes, esters and acids and so on. After a cycle of anaerobic biochemical treatment, the content of organic compounds in the effluent decreased significantly. After the treatment of AFBMFC, 99.9% phenols, 98.4% alcohol and aldehydes and 95.3% nitrogenous compounds were biodegraded. In the effluent, some new compounds (such as tricosane and dibutyl phthalate) were produced. The chemical oxygen demand (COD) of CWW decreased from 3372 to 559 mg/L in the closed-circuit microbial fuel cell, and the COD removal was 83.4 ± 1.0%. The maximum power density of AFBMFC was 2.13 ± 0.01 mW m(-2).

  3. Simultaneous degradation of bad wine and electricity generation with the aid of the coexisting biocatalysts Acetobacter aceti and Gluconobacter roseus.

    PubMed

    Rengasamy, Karthikeyan; Berchmans, Sheela

    2012-01-01

    This study describes the cooperative effect of the two biocatalysts Acetobacter aceti and Gluconobacter roseus for biodegradation as well as current generation. The electro activity of the biofilms of these two microorganisms was investigated by the bioelectrocatalytic oxidation of ethanol and glucose using cyclic voltammetry. Two chamber microbial fuel cells (MFCs) were constructed using single culture of A. aceti (A-MFC), and G. roseus (G-MFC) and also using mixed culture (AG-MFC). Each MFC was fed with four different substrates viz., glucose, ethanol, acetate and bad wine. AG-MFC produced higher power density with glucose (1.05 W/m(3)), ethanol (1.97 W/m(3)), acetate (1.39 W/m(3)) and bad wine (3.82 W/m(3)). COD removal (94%) was maximum for acetate fed MFCs. Higher coulombic efficiency was obtained with bad wine (45%) as the fuel. This work provides the scope of using these biofuel cells in wineries for performing the dual duty of bad wine degradation along with current generation.

  4. MaRIE: Probing Dynamic Processes in Soft Materials Using Advanced Light Sources

    SciTech Connect

    Sykora, Milan; Kober, Edward Martin

    2016-02-16

    Los Alamos National Laboratory has developed a concept for a new research facility, MaRIE: Matter-Radiation Interactions in Extremes. The key motivation for MaRIE is to develop new experimental capabilities needed to fill the existing gaps in our fundamental understanding of materials important for key National Nuclear Security Agency (NNSA) goals. MaRIE will bring two major new capabilities: (a) the ability to characterize the meso- and microstructure of materials in bulk as well as local dynamic response characteristics, and (b) the ability to characterize how this microstructure evolves under NNSA-relevant conditions and impacts the material’s performance in this regime.

  5. Reactive ion etching (RIE) technique for application in crystalline silicon solar cells

    SciTech Connect

    Yoo, Jinsu

    2010-04-15

    Saw damage removal (SDR) and texturing by conventional wet chemical processes with alkali solution etch about 20 micron of silicon wafer on both sides, resulting in thin wafers with which solar cell processing is difficult. Reactive ion etching (RIE) for silicon surface texturing is very effective in reducing surface reflectance of thin crystalline silicon wafers by trapping the light of longer wavelength. High efficiency solar cells were fabricated during this study using optimized RIE. Saw damage removal (SDR) with acidic mixture followed by RIE-texturing showed the decrease in silicon loss by {proportional_to}67% and {proportional_to}70% compared to conventional SDR and texturing by alkaline solution. Also, the crystalline silicon solar cells fabricated by using RIE-texturing showed conversion efficiency as high as 16.7% and 16.1% compared with 16.2%, which was obtained in the case of the cell fabricated with SDR and texturing with NaOH solution. (author)

  6. A comparison of 4 MeV Proton and Co-60 gamma irradiation induced degradation in the electrical characteristics of N-channel MOSFETs

    NASA Astrophysics Data System (ADS)

    Anjum, Arshiya; Vinayakprasanna, N. H.; Pradeep, T. M.; Pushpa, N.; Krishna, J. B. M.; Gnana Prakash, A. P.

    2016-07-01

    N-channel depletion MOSFETs were irradiated with 4 MeV Proton and Co-60 gamma radiation in the dose range of 100 krad(Si) to 100 Mrad(Si). The electrical characteristics of MOSFET such as threshold voltage (Vth), density of interface trapped charges (ΔNit), density of oxide trapped charges (ΔNot), transconductance (gm), mobility (μ), leakage current (IL) and drain saturation current (ID Sat) were studied as a function of dose. A considerable increase in ΔNit and ΔNot and decrease in Vth,gm, μ, and ID Sat was observed after irradiation. The results of 4 MeV Proton irradiation were compared with that of Co-60 gamma radiation and it is found that the degradation is more for the devices irradiated with 4 MeV Protons when compared with the Co-60 gamma radiation. This indicates that Protons induce more trapped charges in the field oxide region when compared to the gamma radiation.

  7. Electrical Degradation in Ceramic Dielectrics

    DTIC Science & Technology

    1988-09-09

    which corresponds to the ionic conductivity. Examples of such plots are shown in Figs. 4, 5, and 6 for undoped and acceptor- doped BaTiO and SrTiO3 , and...out on BaTiO V both doped and undoped, prepared to have precisely controlled compositions. The report takes the form of four independent sections...acceptor- doped behavior was restored. 2. It is shown that the absolute value of the ionic conductivity and the ionic transport number under

  8. The "suevite" conundrum, Part 1: The Ries suevite and Sudbury Onaping Formation compared

    NASA Astrophysics Data System (ADS)

    Osinski, Gordon R.; Grieve, Richard A. F.; Chanou, Anna; Sapers, Haley M.

    2016-12-01

    The term "suevite" has been applied to various impact melt-bearing breccias found in different stratigraphic settings within terrestrial impact craters. Suevite was coined initially for impact glass-bearing breccias from the Ries impact structure, Germany, which is the type locality. Various working hypotheses have been proposed to account for the formation of the Ries suevite deposits over the past several decades, with the most recent being molten-fuel-coolant interaction (MFCI) between an impact melt pool and water. This mechanism is also the working hypothesis for the origin of the bulk of the Onaping Formation at the Sudbury impact structure, Canada. In this study, the key characteristics of the Ries suevite, the Onaping Formation and MFCI deposits from phreatomagmatic volcanic eruptions are compared. The conclusion is that there are clear and significant lithological, stratigraphic, and petrographic observational differences between the Onaping Formation and the Ries suevite. The Onaping Formation, however, shares many key similarities with MFCI deposits, including the presence of layering, their well-sorted and fine-grained nature, and the predominance of vitric particles with similar shapes and lacking included mineral and lithic clasts. These differences argue against the viability of MFCI as a working hypothesis for genesis of the Ries suevite and for a required alternative mechanism for its formation.

  9. RIE-based Pattern Transfer Using Nanoparticle Arrays as Etch Masks

    NASA Astrophysics Data System (ADS)

    Hogg, Chip; Majetich, Sara A.; Bain, James A.

    2009-03-01

    Nanomasking is used to transfer the pattern of a self-assembled array of nanoparticles into an underlying thin film, for potential use as bit-patterned media. We have used this process to investigate the limits of pattern transfer, as a function of gap size in the pattern. Reactive Ion Etching (RIE) is our chosen process, since the gaseous reaction products and high chemical selectivity are ideal features for etching very small gaps. Interstitial surfactant is removed with an O2 plasma, allowing the etchants to penetrate between the particles. Their pattern is transferred into an intermediate SiO2 mask using a CH4-based RIE. This patterned SiO2 layer is finally used as a mask for the MeOH-based RIE which patterns the magnetic film. We present cross-sectional TEM characterization of the etch profiles, as well as magnetic characterization of the film before and after patterning.

  10. Using superconducting undulator for enhanced imaging capabilities of MaRIE

    SciTech Connect

    Yampolsky, Nikolai

    2016-09-22

    MaRIE x-ray free electron laser (FEL) is envisioned to deliver a burst of closely spaced in time pulses for enabling the capability of studying the dynamic processes in a sample. MaRIE capability can be largely enhanced using the superconducting undulator, which has the capability of doubling its period. This technology will allow reaching the photon energy as low as ~200-500 eV. As a result, the MaRIE facility will have a broader photon energy range enabling a larger variety of experiments. The soft x-ray capability is more likely to achieve the 3D imaging of dynamic processes in noncrystal materials than the hard x-ray capability alone.

  11. DLTS Study of RIE-Induced Deep Levels in Si Using p+n Diode Arrays

    NASA Astrophysics Data System (ADS)

    Watanabe, Miyoko Oku; Taguchi, Minoru; Kanzaki, Koichi; Zohta, Yasuhito

    1983-02-01

    Deep levels in Si induced by reactive ion etching (RIE) of SiO2 film have been studied by DLTS. In order to detect the RIE-induced damage existing near the surface region, special device structures consisting of p+n diode arrays are used. It is found that the dominant deep levels produced by RIE are four hole traps. One level at Ev+0.40 eV exhibits the Poole-Frenkel effect, from which it is identified as an acceptor. Another level at Ev+0.46 eV is deduced to be an interstitial iron level from the emission rate. There is a strong decrease in the deep level concentrations upon annealing above 500°C. However, the deep levels do not completely disappear upon annealing at high temperatures. The deep level concentrations correlate well with the current-voltage characteristics of the devices.

  12. Loss of radiogenic argon from shocked granitic clasts in suevite deposits from the Ries Crater

    NASA Technical Reports Server (NTRS)

    Bogard, Donald; Hoerz, Friedrich; Stoeffler, Dieter

    1988-01-01

    Five granite clasts from the Otting and Aumuehle quarries in the suevite ejecta deposits from the Ries Crater, Germany, were characterized with respect to modal composition, the degree of shock, and the loss of radiogenic Ar. The results were used to estimate the relative fractions of total crater volume, which were characterized by undisturbed K-Ar ages, partly reset ages, and essentially complete gas loss. The results suggest that the loss of Ar form the Ries suevite samples occurred in a 'hot' post-impact ejecta layer. It was estimated that less than 50 percent of the material composing the hot Ries ejecta should show at least partially reset K-Ar ages; such materials compose no more than 5 percent of the total displaced crater volume.

  13. Aesthetic restoration of deciduous anterior teeth after removal of carious tissue with Papacárie.

    PubMed

    Motta, Lara J; Martins, Manoela D; Porta, Kristianne P; Bussadori, Sandra K

    2009-01-01

    The development of conservative techniques for the removal of carious tissue and the improvement of dental restoration materials allow better preservation of the dental structure. Chemomechanical caries removal is a conservative and atraumatic alternative. Papacárie is a papain-based material developed to act only on the carious dentin, allowing its easy removal with a blunt curette. This study aims to present a clinical case of aesthetic restoration of both upper deciduous central incisors after the removal of carious tissue with Papacárie.

  14. Alkylated phenol series in lacustrine black shales from the Nördlinger Ries, southern Germany.

    PubMed

    Barakat, Assem O; Baumgart, Susan; Brocks, Peter; Scholz-Böttcher, Barbara M; Rullkötter, Jürgen

    2012-08-01

    Several series of alkylated phenols were detected for the first time in the extractable bitumens of organic matter-rich sediments from the Nördlinger Ries (southern Germany). Most abundant and significant constituents comprise those with n-octadecyl, n-eicosanyl, phytanyl, and iso-pentadecyl and anteiso-pentadecyl substituents. The structures of these compounds are suggested from mass spectrometric and retention time data and coinjection with synthetic standards. Diagenetic alteration of phenolic algal lipids is suggested as a possible way to the formation of these compounds in the Nördlinger Ries sediments.

  15. First Description of Genuine Shatter Cones in Upper Jurassic Limestone Clasts from the Bunte Breccia Impactites of the Ries Crater

    NASA Astrophysics Data System (ADS)

    Poesges, G. A.

    2016-08-01

    The Ries crater produced a wealth of lithologies that host shatter cones. This study reviews the occurrence of shatter cones in the Ries crater and reports the first finds of shatter cones in Upper Jurassic limestone clasts within the Bunte Breccia.

  16. MaRIE: A facility for time-dependent materials science at the mesoscale

    SciTech Connect

    Barnes, Cris William; Kippen, Karen Elizabeth

    2015-02-11

    To meet new and emerging national security issues the Laboratory is stepping up to meet another grand challenge—transitioning from observing to controlling a material’s performance. This challenge requires the best of experiment, modeling, simulation, and computational tools. MaRIE is the Laboratory’s proposed flagship experimental facility intended to meet the challenge.

  17. Hybrid generalized Bosbach and Rie c̆ an states on non-commutative residuated lattices

    NASA Astrophysics Data System (ADS)

    Ma, Zhen Ming; Yang, Wei

    2016-08-01

    Generalized Bosbach and Rie c̆ an states, which are useful for the development of an algebraic theory of probabilistic models for commutative or non-commutative fuzzy logics, have been investigated in the literature. In this paper, a new way arising from generalizing residuated lattice-based filters from commutative case to non-commutative one is applied to introduce new notions of generalized Bosbach and Rie c̆ an states, which are called hybrid ones, on non-commutative residuated lattices is provided, and the relationships between hybrid generalized states and those existing ones are studied, examples show that they are different. In particular, two problems from L.C. Ciungu, G. Georgescu, and C. Mure, "Generalized Bosbach States: Part I" (Archive for Mathematical Logic 52 (2013):335-376) are solved, and properties of hybrid generalized states, which are similar to those on commutative residuated lattices, are obtained without the condition "strong".

  18. Reactive Ion Etching (RIE) of silicon for the technology of nanoelectronic devices and structures

    NASA Astrophysics Data System (ADS)

    Wiśniewski, Piotr; Mroczyński, Robert; Majkusiak, Bogdan

    2016-12-01

    In this work we present the investigations aimed at the optimization of the technology of Reactive Ion Etching in sulfur hexafluoride (SF6) plasma of silicon, which is necessary during fabrication of TFET according to the original concept of the device designed at Institute of Microelectronics and Optoelectronics (IMiO) of Warsaw University of Technology (WUT) laboratory. We have performed a two-stage optimization of RIE process' parameters in order to obtain a controllable process characterized by good selectivity and anisotropy. Presented in this study findings have shown that the SF6 flow most significantly influence onto the RIE process' results. Selected and optimized processing step will be used in the course of the fabrication of TFET devices, in future.

  19. Analysis of in-situ electrical conductivity data from the HFIR TRIST-ER1 experiment

    SciTech Connect

    Zinkle, S.J.; Snead, L.L.; Shikama, T.

    1997-08-01

    The current vs. applied voltage data generated from the HFIR TRIST-ER1 experiment have been analyzed to determine the electrical conductivity of the 15 aluminum oxide specimens and the MgO-insulated electrical cables as a function of irradiation dose. With the exception of the 0.05%Cr-doped sapphire (ruby) specimen, the electrical conductivity of the alumina specimens remained at the expected radiation induced conductivity (RIC) level of <10{sup -6} S/m during full-power reactor irradiation (10-16 kGy/s) at 450-500{degrees}C up to a maximum dose of {approximately}3 dpa. The ruby specimen showed a rapid initial increase in conductivity to {approximately}2 x 10{sup -4} S/m after {approximately}0.1 dpa, followed by a gradual decrease to <1 x 10{sup -6} S/m after 2 dpa. Nonohmic electrical behavior was observed in all of the specimens, and was attributed to preferential attraction of ionized electrons in the capsule gas to the unshielded low-side bare electrical leads emanating from the subcapsules. The electrical conductivity was determined from the slope of the specimen current vs. voltage curve at negative voltages, where the gas ionization effect was minimized. Dielectric breakdown tests performed on unirradiated mineral-insulated coaxial cables identical to those used in the high voltage coaxial cables during the 3-month irradiation is attributable to thermal dielectric breakdown in the glass seals at the end of the cables, as opposed to a radiation-induced electrical degradation (RIED) effect.

  20. In-situ measurement of the electrical conductivity of aluminum oxide in HFIR

    SciTech Connect

    Zinkle, S.J.; White, D.P.; Snead, L.L.

    1996-10-01

    A collaborative DOE/Monbusho irradiation experiment has been completed which measured the in-situ electrical resistivity of 12 different grades of aluminum oxide during HFIR neutron irradiation at 450{degrees}C. No evidence for bulk RIED was observed following irradiation to a maximum dose of 3 dpa with an applied dc electric field of 200 V/mm.

  1. Final PV module degradation-analysis report

    SciTech Connect

    Themelis, M P

    1982-06-01

    Visual and electrical degradation analyses were performed on 47 modules from: the Natural Bridges National Monument (NBNM) in Utah; Massachusetts Institute of Technology (MIT) in Cambridge, Massachusetts; and the University of Nebraska at Mead, Nebraska. Such problems as discoloration, cracking, scratches, and electrical degradation were detected. (LEW)

  2. An Overview of the MaRIE X-FEL and Electron Radiography LINAC RF Systems

    SciTech Connect

    Bradley, Joseph Thomas III; Rees, Daniel Earl; Scheinker, Alexander; Sheffield, Richard L.

    2015-05-04

    The purpose of the Matter-Radiation Interactions in Extremes (MaRIE) facility at Los Alamos National Laboratory is to investigate the performance limits of materials in extreme environments. The MaRIE facility will utilize a 12 GeV linac to drive an X-ray Free-Electron Laser (FEL). Most of the same linac will also be used to perform electron radiography. The main linac is driven by two shorter linacs; one short linac optimized for X-FEL pulses and one for electron radiography. The RF systems have historically been the one of the largest single component costs of a linac. We will describe the details of the different types of RF systems required by each part of the linacs. Starting with the High Power RF system, we will present our methodology for the choice of RF system peak power and pulselength with respect to klystron parameters, modulator parameters, performance requirements and relative costs. We will also present an overview of the Low Level RF systems that are proposed for MaRIE and briefly describe their use with some proposed control schemes.

  3. RIE surface texturing for optimum light trapping in multicrystalline silicon solar cells

    NASA Astrophysics Data System (ADS)

    Yoo, Jinsu; Cho, Junsik; Han, Kyumin; Yi, Junsin

    2012-06-01

    Optical losses by reflection and transmission of the incident light should be reduced to improve the efficiency of solar cells. Compared with antireflection coatings, surface texturing is a more persistent and effective solution aiming at reducing light reflection losses. Alkali (NaOH, KOH) or acidic (HF, HNO3, CH3COOH) chemicals are used in conventional solar cell production lines for wet chemical texturing. However, Surface texturing is too difficult to apply to solar cell fabrication with thinner wafers due to the large amount of silicon loss caused by saw damage removal (SDR) and the texturing process for multicrystalline silicon (mc-Si). In order to solve the problems, reactive ion etching (RIE) has been applied for surface texturing of solar cell wafers. The RIE method can be effective in the reducing surface reflection with low silicon loss. In this study, we, therefore, fabricated a large-area (243.3 cm2) mc-Si solar cell by maskless surface texturing using a SF6/O2 RIE process. Also, we achieved a conversion efficiency (Eff), open circuit voltage (Voc), short circuit current density (Jsc) and fill factor (FF) as high as 17.2%, 616 mV, 35.1 mA/cm2, and 79.6%, respectively, which are suitable for fabricating thin crystalline silicon solar cells at low cost and with high efficiency.

  4. ISEC-3: Results from the third in-situ electrical conductivity test on polycrystaline alumina

    SciTech Connect

    Snead, L.L.; White, D.P.; Eatherly, W.S.; Zinkle, S.J.

    1996-04-01

    An experimental investigation of radiation induced electrical degradation (RIED) has been performed at the High Flux Beam Reactor (HFBR) at Brookhaven National Laboratory. In this study (the third in a series of experiments at the HFBR) the effects of neutron irradiation on the electrical conductivity of Wesgo AL995 polycrystalline alumina has been investigated at approximately 450{degrees}C. The capsule design used in this study is very similiar to a design used in the first two experiments in this series with some improvements made to a design used in the first two experiments in this series with some improvements made in the cable terminations. A guard ring configuration was used on the disk shaped sample. Triaxial mineral insulated cable was used as the data lead from the sputter deposited guard ring and central electrode of the sample, and coaxial mineral insulated cable was used as the sample power lead. No evidence for REID was observed in this series of experiments to a dose level of {approx}1.8 dpa. The effect of neutron irradiation on the electrical properties of two mineral insulated (MgO) cables was also investigated.

  5. GROUNDWATER AND SOIL REMEDIATION USING ELECTRICAL FIELD

    EPA Science Inventory

    Enhancements of contaminants removal and degradation in low permeability soils by electrical fields are achieved by the processes of electrical heating, electrokinetics, and electrochemical reactions. Electrical heating increases soil temperature resulting in the increase of cont...

  6. Production of electricity and hydrogen by photocatalytic degradation of organic wastes in a photoelectrochemical cell: the concept of the Photofuelcell: a review of a re-emerging research field.

    PubMed

    Lianos, Panagiotis

    2011-01-30

    The present review aims to give to a researcher who has no experience with Photofuelcells all necessary basic knowledge to join the field without much trouble and to give to an experienced researcher a handy manual of reference. The author has dealt with the principal matters related with the design of a photoelectrochemical cell and the factors that affect efficient production of electricity by photocatalytic degradation of (principally) organic and (secondarily) inorganic waste materials. A large portion of the paper is devoted to the review of materials used for making a photoanode since most of the accomplished research is on this exact matter. The paper also briefly reviews the materials used to make the rest of the components of the cell as well as the models of cell efficiency and photodegradation procedures during cell operation.

  7. Sobre o uso das séries de Puiseux em mecanica celeste

    NASA Astrophysics Data System (ADS)

    Miloni, O. I.

    2003-08-01

    Neste trabalho é apresentada uma demonstração do uso dos diferentes desenvolvimentos em séries para as equações de perturbação em Mecânica Celeste no marco Hamiltoniano. Em trabalhos clássicos como os de Poincaré (Poincaré, 1893) por exemplo, já esta planteado o uso de potências não inteiras no pequeno parâmetro, o que evidencia a não analiticidade das funções quando uma ressonância ocorre. Nestes trabalhos os desenvolvimentos são na raíz quadrada da massa de Júpiter (o pequeno parâmetro). Mais recentemente (Ferraz-Mello, 1985) outros tipos de desenvolvimentos foram aplicados modificando substancialmente as ordens de grandeza e a velocidade de convergência das séries. Com esta abordagem, os desenvolvimentos foram expressados em termos da raíz cúbica do pequeno parâmetro. Neste trabalho apresentamos um enfoque geral, onde os diferentes tipos de desenvolvimentos em séries de Puiseux (Valiron, 1950) são obtidos a partir da aplicação de Teorema de Preparação de Weierstrass (Goursat, 1916) considerando a equação de Hamilton-Jacobi como uma equação algébrica. Os resultados são aplicados ao problema restrito dos três corpos em ressonância de primeira ordem e, dependendo da grandeza da excentricidade do asteróide em relação à de Júpiter, obtemos os diferentes desenvolvimentos, em raíz quadrada ou raíz cúbica da massa de Júpiter.

  8. Evidence for a spatially extensive hydrothermal system at the Ries impact structure, Germany

    NASA Astrophysics Data System (ADS)

    Sapers, H. M.; Osinski, G. R.; Flemming, R. L.; Buitenhuis, E.; Banerjee, N. R.; Tornabene, L. L.; Blain, S.; Hainge, J.

    2017-02-01

    The 15 Ma, 26 km diameter Ries impact structure in south-central Germany was one of the first terrestrial impact structures where evidence of impact-associated hydrothermal alteration was recognized. Previous studies suggested that pervasive, high-temperature hydrothermal activity was restricted to the area within the "inner ring" (i.e., the crater-fill impactite units). Here we present mineralogical evidence for localized hydrothermal activity in the ejecta beyond the crater rim in two previously unstudied settings: a pervasively altered lens of suevite ejecta directly overlying the Bunte Breccia at the Aumühle quarry; and suevite ejecta at depth overlain by 20 m of lacustrine sediments sampled by the Wörnitzostheim 1965 drill core. A comprehensive set of X-ray diffraction analyses indicates five distinct alteration regimes (1) surficial ambient weathering characterized by smectite and a minor illitic component; (2) locally restricted hydrothermal activity characterized by an illitic component and minor smectite; (3) hydrothermal activity at depth characterized by smectite, a minor illitic component, and calcite; (4) hydrothermal activity at depth characterized by smectite, a minor illitic component, calcite, zeolites, and clinochlore; and (5) pervasive hydrothermal activity at depth characterized by smectite, a minor illitic component, and minor clinochlore. These data spatially extend the Ries postimpact hydrothermal system suggesting a much more extensive, complex, and dynamic system than previously thought. Constraining the mineralogical alteration regimes at the Ries impact structure may also further our understanding of impact-associated phyllosilicate formation on Mars with implications for climate models and habitability.

  9. Low-Power RIE of SiO2 in CHF3 To Obtain Steep Sidewalls

    NASA Technical Reports Server (NTRS)

    Turner, Tasha; Wu, Chi

    2003-01-01

    A reactive-ion etching (RIE) process has been developed to enable the formation of holes with steep sidewalls in a layer of silicon dioxide that covers a silicon substrate. The holes in question are through the thickness of the SiO2 and are used to define silicon substrate areas to be etched or to be built upon through epitaxial deposition of silicon. The sidewalls of these holes are required to be vertical in order to ensure that the sidewalls of the holes to be etched in the substrate or the sidewalls of the epitaxial deposits, respectively, also turn out to be vertical.

  10. Investigation on the Neff reverse annealing effect using TSC/I-DLTS: Relationship between neutron induced microscopic defects and silicon detector electrical degradations

    NASA Astrophysics Data System (ADS)

    Li, Z.; Li, C. J.; Eremin, V.; Verbitskaya, E.

    1996-02-01

    Neutron induced defect levels in high resistivity silicon detectors have been studied using a current-based macroscopic defect analysis system: thermally stimulated current (TSC) and current deep level transient spectroscopy (I-DLTS).These studies have been correlated to the traditional C—V I—V, and transient current and charge techniques (TCT/TChT) after neutron radiation and subsequent thermal anneals. It has been found that the increases of the space charge density, Neff in irradiated detectors after thermal anneals ( Neff reverse anneal) correspond to the increases of deep levels in the silicon bandgap. In particular, increases of the double vacancy center (V—V and V—V - …) and/or C i-O i level have good correlations with the Neff reverse anneal. It has also been observed that the leakage current of highly irradiated ( Φn > 10 13 n/cm 2) detectors increases after thermal anneals, which is different from the leakage current annealing behavior of slightly irradiated ( Φn < 10 13 n/cm 2) detectors. It is apparent that V—V center and/or C i—O i, level play important roles in both Neff and leakage current degradations for highly irradiated high resistivity silicon detectors.

  11. Photocarrier radiometry for predicting the degradation of electrical parameters of monocrystalline silicon (c-Si) solar cell irradiated by 100 KeV proton beams

    NASA Astrophysics Data System (ADS)

    Song, P.; Liu, J. Y.; Yuan, H. M.; Oliullah, Md.; Wang, F.; Wang, Y.

    2016-09-01

    In this study, the monocrystalline silicon (c-Si) solar cell irradiated by 100 KeV proton beams at various fluences is investigated. A one-dimensional two-layer carrier density wave model has been developed to estimate the minority carrier lifetime of n-region and p-region of the non-irradiated c-Si solar cell by best fitting with the experimental photocarrier radiometry (PCR) signal (the amplitude and the phase). Furthermore, the lifetime is used to determine the initial defect density of the quasi-neutral region (QNR) of the solar cell to predict its I-V characteristics. The theoretically predicted short-circuit current density (Jsc), and open-circuit voltage (Voc) of the non-irradiated samples are in good agreement with experiment. Then a three-region defect distribution model for the c-Si solar cell irradiated by proton beams is carried out to describe the defect density distribution according to Monte Carlo simulation results and the initial defect density of the non-irradiated sample. Finally, we find that the electrical measurements of Jsc and Voc of the solar cells irradiated at different fluences using 100 KeV proton beams are consistent with the PCR predicting results.

  12. Shallow drilling in the 'Bunte Breccia' impact deposits, Ries Crater, Germany

    NASA Technical Reports Server (NTRS)

    Hoerz, F.; Gall, H.; Huettner, R.; Oberbeck, V. R.

    1977-01-01

    The paper is a field report concerning a shallow core drilling program in the multicolored breccia deposits which constitute 90% of all the impact breccias beyond the outer rim of the Ries, a 26-km-diam impact crater. About 480 m of core was recovered from 11 locations with radial ranges between 16.5 and 35 km from the crater center. The cores consist of breccias, whose components are derived from the crater itself and the terrain outside the crater. The local components dominate the breccias at the larger ranges, and possibly constitute more than 90% of the breccia volume at the greatest distances investigated. The great depth of the Bunte Breccia (84 m at 27 km range), together with the preponderance of local components, necessitates an emplacement mechanism that ploughed up and mixed the crater surroundings to depths greater than 50 m.

  13. Aquisição de Estreptococos Mutans e Desenvolvimento de Cárie Dental em Primogênitos

    PubMed Central

    NOCE, Erica; RUBIRA, Cassia Maria Fischer; da Silva ROSA, Odila Pereira; da SILVA, Salete Moura Bonifácio; BRETZ, Walter Antonio

    2011-01-01

    Objetivo Avaliar o momento de aquisição de estreptococos mutans (EM), desenvolvimento de cárie dental e as variáveis a eles associadas no decorrer de 23 meses, em primogênitos de famílias de baixo nível socioeconômico, desde os sete meses de idade. Método A amostra foi selecionada com base em mães densamente colonizadas por EM, incluindo todos os membros de 14 famílias que conviviam na mesma casa. Foram envolvidos no estudo 14 mães, pais e primogênitos e 8 parentes, na maioria avós. Exames clínicos e radiográficos iniciais determinaram os índices de cárie e condição periodontal dos adultos. Contagens de EM foram feitas em todos os adultos nas duas primeiras visitas. Nas crianças foram avaliados os níveis de EM, o número de dentes e de cáries, em quatro visitas. Resultados A prevalência de EM nos adultos foi alta, estando ausente em apenas um dos pais. EM foram detectados em 1, 2, 3 e 10 crianças, respectivamente nas visitas #1, 2, 3 e 4. A cárie dental foi detectada em apenas três crianças na última visita (aos 30 meses de idade), as quais apresentaram escores de EM significantemente maiores que as crianças sem cárie, na mesma visita. Conclusão Exclusivamente a condição social de baixa renda e mães densamente colonizadas por EM não são sinônimo de colonização precoce e alta atividade de cárie em crianças cuidadas em casa. O desenvolvimento de cárie está significantemente associado a escores elevados de EM nas crianças. PMID:22022218

  14. Electrical condition monitoring method for polymers

    DOEpatents

    Watkins, Jr. Kenneth S.; Morris, Shelby J.; Masakowski, Daniel D.; Wong, Ching Ping; Luo, Shijian

    2010-02-16

    An electrical condition monitoring method utilizes measurement of electrical resistivity of a conductive composite degradation sensor to monitor environmentally induced degradation of a polymeric product such as insulated wire and cable. The degradation sensor comprises a polymeric matrix and conductive filler. The polymeric matrix may be a polymer used in the product, or it may be a polymer with degradation properties similar to that of a polymer used in the product. The method comprises a means for communicating the resistivity to a measuring instrument and a means to correlate resistivity of the degradation sensor with environmentally induced degradation of the product.

  15. Polysaccharide Degradation

    NASA Astrophysics Data System (ADS)

    Stone, Bruce A.; Svensson, Birte; Collins, Michelle E.; Rastall, Robert A.

    An overview of current and potential enzymes used to degrade polysaccharides is presented. Such depolymerases are comprised of glycoside hydrolases, glycosyl transferases, phosphorylases and lyases, and their classification, active sites and action patterns are discussed. Additionally, the mechanisms that these enzymes use to cleave glycosidic linkages is reviewed as are inhibitors of depolymerase activity; reagents which react with amino acid residues, glycoside derivatives, transition state inhibitors and proteinaceous inhibitors. The characterization of various enzymes of microbial, animal or plant origin has led to their widespread use in the production of important oligosaccharides which can be incorporated into food stuffs. Sources of polysaccharides of particular interest in this chapter are those from plants and include inulin, dextran, xylan and pectin, as their hydrolysis products are purported to be functional foods in the context of gastrointestinal health. An alternative use of degraded polysaccharides is in the treatment of disease. The possibility exists to treat bacterial exopolysaccharide with lyases from bacteriophage to produce oligosaccharides exhibiting bioactive sequences. Although this area is currently in its infancy the knowledge is available to investigate further.

  16. Mid-infrared spectroscopy of impactites from the Nördlinger Ries impact crater

    NASA Astrophysics Data System (ADS)

    Morlok, Andreas; Stojic, Aleksandra; Dittmar, Isabelle; Hiesinger, Harald; Tiedeken, Manuel; Sohn, Martin; Weber, Iris; Helbert, Joern

    2016-01-01

    This study is part of an effort to build a mid-infrared database (7-14 μm) of spectra for MERTIS (Mercury Radiometer and Thermal Infrared Spectrometer), an instrument onboard of the ESA/JAXA BepiColombo space probe to be launched to Mercury in 2017. Mercury was exposed to abundant impacts throughout its history. This study of terrestrial impactites can provide estimates of the effects of shock metamorphism on the mid-infrared spectral properties of planetary materials. In this study, we focus on the Nördlinger Ries crater in Southern Germany, a well preserved and easily accessible impact crater with abundant suevite impactites. Suevite and melt glass bulk samples from Otting and Aumühle, as well as red suevite from Polsingen were characterized and their reflectance spectra in mid-infrared range obtained. In addition, in-situ mid-infrared spectra were made from glasses and matrix areas in thin sections. The results show similar, but distinguishable spectra for both bulk suevite and melt glass samples, as well as in-situ measurements. Impact melt glass from Aumühle and Otting have spectra dominated by a Reststrahlen band at 9.3-9.6 μm. Bulk melt rock from Polsingen and bulk suevite and fine-grained matrix have their strongest band between 9.4 and 9.6 μm. There are also features between 8.5 and 9 μm, and 12.5-12.8 μm associated with crystalline phases. There is evidence of weathering products in the fine-grained matrix, such as smectites. Mercury endured many impacts with impactors of all sizes over its history. So spectral characteristics observed for impactites formed only in a single impact like in the Ries impact event can be expected to be very common on planetary bodies exposed to many more impacts in their past. We conclude that in mid-infrared remote sensing data the surface of Mercury can be expected to be dominated by features of amorphous materials.

  17. Analysis of the LSC microbunching instability in MaRIE linac reference design

    SciTech Connect

    Yampolsky, Nikolai

    2016-09-22

    In this report we estimate the effect of the microbunching instability in the MaRIE XFEL linac. The reference design for the linac is described in a separate report. The parameters of the L1, L2, and L3 linacs as well as BC1 and BC2 bunch compressors were the same as in the referenced report. The beam dynamics was assumed to be linear along the accelerator (which is a reasonable assumption for estimating the effect of the microbunching instability). The parameters of the bunch also match the parameters described in the referenced report. Additionally, it was assumed that the beam radius is equal to R = 100 m and does not change along linac. This assumption needs to be revisited at later studies. The beam dynamics during acceleration was accounted in the matrix formalism using a Matlab code. The input parameters for the linacs are: RF peak gradient, RF frequency, RF phase, linac length, and initial beam energy. The energy gain and the imposed chirp are calculated based on the RF parameters self-consistently. The bunch compressors are accounted in the matrix formalism as well. Each chicane is characterized by the beam energy and the R56 matrix element. It was confirmed that the linac and beam parameters described previously provide two-stage bunch compression with compression ratios of 10 and 20 resulting in the bunch of 3kA peak current.

  18. Mineral-produced high-pressure striae and clay polish: Key evidence for nonballistic transport of ejecta from Ries crater

    USGS Publications Warehouse

    Chao, E.C.T.

    1976-01-01

    Recently discovered mineral-produced, deeply incised striae and mirror-like polish on broken surfaces of limestone fragments from the sedimentary ejecta of the Ries impact crater of southern Germany are described. The striae and polish were produced under high confining pressures during high-velocity nonballistic transport of the ejecta mass within the time span of the cratering event (measured in terms of seconds). The striae on these fragments were produced by scouring by small mineral grains embedded in the surrounding clay matrix, and the polish was formed under the same condition, by movements of relatively fragment-free clay against the fragment surfaces. The occurrence of these striae and polish is key evidence for estimating the distribution and determining the relative importance of nonballistic and ballistic transport of ejecta from the shallow Ries stony meteorite impact crater.

  19. Geochemical studies of the SUBO 18 (Enkingen) drill core and other impact breccias from the Ries crater, Germany

    NASA Astrophysics Data System (ADS)

    Reimold, Wolf Uwe; McDonald, Iain; Schmitt, Ralf-Thomas; Hansen, Birgit; Jacob, Juliane; Koeberl, Christian

    2013-09-01

    Suevite and melt breccia compositions in the boreholes Enkingen and Polsingen are compared with compositions of suevites from other Ries boreholes and surface locations and discussed in terms of implications for impact breccia genesis. No significant differences in average chemical compositions for the various drill cores or surface samples are noted. Compositions of suevite and melt breccia from southern and northeastern sectors of the Ries crater do not significantly differ. This is in stark contrast to the published variations between within-crater and out-of-crater suevites from northern and southern sectors of the Bosumtwi impact structure, Ghana. Locally occurring alteration overprint on drill cores—especially strong on the carbonate-impregnated suevite specimens of the Enkingen borehole—does affect the average compositions. Overall, the composition of the analyzed impact breccias from Ries are characterized by very little macroscopically or microscopically recognized sediment-clast component; the clast populations of suevite and impact melt breccia are dominated consistently by granitic and intermediate granitoid components. The Polsingen breccia is significantly enriched in a dioritic clast component. Overall, chemical compositions are of intermediate composition as well, with dioritic-granodioritic silica contents, and relatively small contributions from mafic target components. Selected suevite samples from the Enkingen core have elevated Ni, Co, Cr, and Ir contents compared with previously analyzed suevites from the Ries crater, which suggest a small meteoritic component. Platinum-group element (PGE) concentrations for some of the enriched samples indicate somewhat elevated concentrations and near-chondritic ratios of the most immobile PGE, consistent with an extraterrestrial contribution of 0.1-0.2% chondrite-equivalent.

  20. Influence of SiCl sub 4 reactive ion etching on the electrical characteristics of GaAs

    SciTech Connect

    Lootens, D. , Laboratorium voor Elektromagnetisme en Acoustica , Sint-Pietersnieuwstraat 41, B-9000 Gent ); Clauws, P. ); Van Daele, P.; Demeester, P. , Laboratorium voor Elektromagnetisme en Acoustica , Sint-Pietersnieuwstraat 41, B-9000 Gent )

    1991-05-05

    SiCl{sub 4}-RIE causes electrical damage to GaAs strongly related to doping type and level. Changes in C-V and DLTS-measurements can be related to EL2-defects. Explanations for observed differences in n-type and p-type material will be presented.

  1. Radiation-induced degradation of DNA bases

    NASA Astrophysics Data System (ADS)

    Douki, T.; Delatour, T.; Martini, R.; Cadet, J.

    1999-01-01

    Radio-induced degradation of DNA involves radical processes. A series of lesions among the major bases degradation products has been measured in isolated DNA exposed to gamma radiation in aerated aqueous solution. Degradation can be accounted for by the formation of hydroxyl radicals upon radiolysis of water (indirect effect). The four bases are degraded in high yield. Direct effect has been mimicked by photo-induced electron abstraction from the bases producing their radical cation. Quantification of the modified bases showed that guanine is the preferential target. This can be explained by its lower oxidation potential and charge transfer phenomena. La décomposition radio-induite de l'ADN fait intervenir des processus radicalaires. Une série de lésions choisies parmi les produits majeurs de dégradation des bases a été mesurée dans de l'ADN isolé exposé au rayonnement en solution aqueuse aérée. Les modifications sont alors dues aux radicaux hydroxyles produits par la radiolyse de l'eau (effet indirect) et les quatre bases sont efficacement dégradées. L'arrachement d'électrons aux bases par photosensibilisation pour produire leur radical cation, a été utilisé comme modèle de l'effet direct. La quantification des bases modifiées montre que la guanine est préférentiellement dégradée. Cette observation peut s'expliquer par le plus faible potentiel d'oxydation de cette base ainsi que par les phénomènes de transfert de charge vers les guanines.

  2. Elastomer degradation sensor

    SciTech Connect

    Olness, D.U.; Hirschfeld, T.B.

    1989-06-01

    This document describes the present invention which is method and apparatus using piezoelectric oscillators as elastomer degradation sensors, particularly as in situ sensors. A piezoelectric material is placed in contact with an elastomer to form an oscillating system. The piezoelectric may contact a surface of the elastomer or be embedded therein. The elastomer can be in situ in a piece of equipment or vehicle. The characteristics of the piezoelectric material, such as size, shape, and composition, and the elasticity of the elastomer determine the resonant frequency and other properties or parameters of the oscillating system. The resonant oscillation of the oscillating system is used to drive a simple electric oscillator circuit. The frequency of this oscillator circuit, and hence the resonant frequency of the oscillating system, is measured with standard frequency counting electronics. Changes in the resonance frequency of the oscillating system indicate changes in the elastic properties of the elastomer. 7 figs.

  3. Putative Bioalteration Textures Hosted Within Impact Melt Glasses From the Ries Crater, Germany

    NASA Astrophysics Data System (ADS)

    Sapers, H. M.; Osinski, G. R.; Banerjee, N. R.

    2009-05-01

    Impact cratering is a ubiquitous geological process on solid bodies. Any hypervelocity impact into a H2O- rich target has the potential to generate hydrothermal systems [1]. Recent research has suggested that such impact-induced environments may be conducive to microbial colonization [e.g., 2]. Bioalteration of terrestrial basaltic glasses produces characteristic tubular and granular aggregate textures. Such bioalteration textures preserved in Archean greenstone belts constitute one of the oldest records of life on Earth [3]. Our examination of glasses from the Ries crater in Germany has revealed tubular textures with remarkably similar morphologies to those seen in volcanic glasses. The hyperthermophilic root of the 16S phylogenic tree of life suggests an essential role for thermophilic environments in the origin or the early evolutionary history of life on Earth. Previous work has associated primitive life on Earth with submarine volcanic activity suggesting that submarine hydrothermal settings may have played an essential role in the origin of life [e.g., 4]. Impact-induced hydrothermal systems share many characteristics with submarine volcanic hydrothermal systems including the presence of chemical and thermal energy for microbial metabolism. Interestingly, the Late Heavy Bombardment period, during which life purportedly arose on Earth, was characterized by a high impact flux. Thus, impact-generated habitats were likely much more common on Earth than submarine hydrothermal systems suggesting the former as a more statistically probable habitat for the origin of life. Here we present preliminary data characterizing the putative bioalteration structures hosted within the Ries impact glasses. Establishing the biogenecity of the alteration structures observed in these glasses may have significant astrobiological implications: impact glasses share many similarities with volcanic glasses, however, fundamental differences make impact glasses unique geochemical systems

  4. Chemistry, small-scale inhomogeneity, and formation of moldavites as condensates from sands vaporized by the Ries impact

    NASA Astrophysics Data System (ADS)

    von Engelhardt, Wolf; Berthold, Christoph; Wenzel, Thomas; Dehner, Thomas

    2005-12-01

    The formation of the Ries impact and the moldavites have identical radiogenic ages of 14.3 Ma. According to this conformity in age moldavites are generally regarded as products of the Ries impact. This paper, which is divided into two sections, deals with two aspects of the moldavite-forming process: the formation of moldavite bodies by accretion of small precursors, and the physical and chemical conditions under which these primary units originated from sands which covered the Ries impact site. First, the chemical inhomogeneity of moldavite glasses is investigated in sections of 11 moldavites, using back scattered electron (BSE) images and electron microprobe analyses on 0.4-2.7 mm long traverses. Schlieren and lechatelierite particles are interpreted as relics of small, chemically different precursors, which accumulated to larger moldavite bodies at temperatures too low to be efficient for mixing. The patterns of schlieren and lechatelierite inclusions represent two successive rheological regimes: Small agglomerating primary melt units were extended into thin lamellae and threads under conditions of laminar flow. As evidenced by folded textures, these fluidal arrays were later plastically deformed under conditions of compressional stress. To elucidate the production of the primary melt units by the Ries impact, in the second section the geologic situation of the Ries area is considered with regard to possible source materials. The site of the Ries impact, situated at the northern border of the pre-Alpine Molasse basin, was covered at the time of the impact by fluviatile sediments of the lower sequence of the Obere Süßwasser-Molasse (OSM) Formation of Middle Miocene age, consisting of sands, marly sands and clays. Chemical analyses for major and trace elements of 38 moldavites from Bohemia and Moravia, and of 28 samples of the OSM Formation, collected from outcrops and drill holes, immediately south of the Ries crater and south of the Danube, show chemical

  5. Target delamination by spallation and ejecta dragging: An example from the Ries crater's periphery

    NASA Astrophysics Data System (ADS)

    Kenkmann, Thomas; Ivanov, Boris A.

    2006-11-01

    Subhorizontal shear planes (detachments) are observed in bedded limestones in the periphery of the Ries impact crater, Germany. These detachments occur at 0.8-1.8 crater radii distance from the crater center beneath deposits of the continuous ejecta blanket. Striations on detachment planes and offsets of markers indicate top-outward shearing with radial slip vectors. Detachments were found at depths between a few meters and more than 50 m beneath the target surface. The displacements along these faults range from meters to decameters and decrease with increasing depth and distance from the crater center. With increasing crater distance, detachment horizons tend to climb to shallower levels. Cross-cutting relationships to faults associated with the crater collapse indicate that detachment faulting started prior to the collapse but continued during crater modification. Numerical modeling of the cratering process shows that near-surface deformation outside the transient crater is induced by two separate mechanisms: (i) weak spallation by interference of shock and release waves near the target surface and (ii) subsequent dragging by the deposition of the ejecta curtain. Spallation causes an upward and outward directed motion of target material that increases in magnitude toward the target surface. It leads to decoupling of the uppermost target layers in the early cratering stage without totally disintegrating the rock. The subsequent arrival of the oblique impact shower of the ejecta curtain at the target surface delivers a horizontal momentum to the uppermost target area and results in a second horizontal displacement increment by dragging. With increasing depth this effect vanishes rapidly. Spallation decoupling and subsequent ejecta dragging of near-surface rocks is probably a general cratering mechanism around craters in layered targets with weak interbeds.

  6. New Shocked Calcite and Fe Grains from Noerdlingen Ries Impact Crater

    NASA Astrophysics Data System (ADS)

    Miura, Y.

    1995-09-01

    Shocked minerals with simple chemical composition of silica, carbon or iron material reveal high-pressure phase during compression process [1]. As calcite mineral shows high-pressure phase of aragonite it should have the "shocked phase" formed from high-pressure phase mixed with quenched materials of gas-melt reaction [2,3,4]. The main purposes of this paper are (1) to discuss new shocked materials of calcite found in the Noerdlingen Ries impact crater. Germany and artificial impact phases. and (2) to show new findings of fine Fe-grains and anomalous plagioclase in suevite. Single grains of anomalous calcite for X-ray analysis were selected from limestone with wormy or bubble-included texture in Buschelberg Ries impact crater (sample R8) [3 4]. Powdered and single grain samples of anomalous calcites show low X-ray intensity and high Bragg angle shift. compared with standard calcite of Akiyoshi limestone as listed in Table 1 [2.3.4]. The unit-cell dimensions of the single grain measured with the four-axes X-ray diffractometer in Yamaguchi University were determined by the least square calculation from the "highest X-ray intensity peak" of each crystal plane which is the same data of the powdered X-ray diffraction sample as an average structure . Both powdered and single grain data reveal high density of 2.76 g/cm^3 (between aragonite of density: rho=2.8g/cm^3, and normal calcite: rho=2.71g/cm^3) of the calcite cell which is the same characters of shocked phases of quartz or graphite [1,2,3,4] (Table 1). Anomalous calcite contains minor amount of Si Fe Ti, though major cation is Ca of 99.4% in cation content. These foreign elements are mixed with during the formation in vapor plume [5]. Table 1, showing the x-ray density and unit-cell parameters of anomalous shocked calcite with high density from Ries and artificial impact craters, appears here in the hard copy. Two types of shocked calcites are found in artificial impact experiments of railgun of the ISAS. Japan. (a

  7. CONDENSED MATTER: ELECTRONIC STRUCTURE, ELECTRICAL, MAGNETIC, AND OPTICAL PROPERTIES: Study on the degradation of NMOSFETs with ultra-thin gate oxide under channel hot electron stress at high temperature

    NASA Astrophysics Data System (ADS)

    Hu, Shi-Gang; Hao, Yue; Ma, Xiao-Hua; Cao, Yan-Rong; Chen, Chi; Wu, Xiao-Feng

    2009-12-01

    This paper studies the degradation of device parameters and that of stress induced leakage current (SILC) of thin tunnel gate oxide under channel hot electron (CHE) stress at high temperature by using n-channel metal oxide semiconductor field effect transistors (NMOSFETs) with 1.4-nm gate oxides. The degradation of device parameters under CHE stress exhibits saturating time dependence at high temperature. The emphasis of this paper is on SILC of an ultra-thin-gate-oxide under CHE stress at high temperature. Based on the experimental results, it is found that there is a linear correlation between SILC degradation and Vh degradation in NMOSFETs during CHE stress. A model of the combined effect of oxide trapped negative charges and interface traps is developed to explain the origin of SILC during CHE stress.

  8. Chemistry of Tertiary sediments in the surroundings of the Ries impact structure and moldavite formation revisited

    NASA Astrophysics Data System (ADS)

    Žák, Karel; Skála, Roman; Řanda, Zdeněk; Mizera, Jiří; Heissig, Kurt; Ackerman, Lukáš; Ďurišová, Jana; Jonášová, Šárka; Kameník, Jan; Magna, Tomáš

    2016-04-01

    Moldavites, tektites of the Central European strewn field, have been traditionally linked with the Ries impact structure in Germany. They are supposed to be derived mainly from the near-surface sediments of the Upper Freshwater Molasse of Miocene age that probably covered the target area before the impact. Comparison of the chemical composition of moldavites with that of inferred source materials requires recalculation of the composition of sediments to their water-, organic carbon- and carbon dioxide-free residuum. This recalculation reflects the fact that these compounds were lost almost completely from the target materials during their transformation to moldavites. Strong depletions in concentrations of many elements in moldavites relative to the source sediments (e.g., Mo, Cu, Ag, Sb, As, Fe) contrast with enrichments of several elements in moldavites (e.g., Cs, Ba, K, Rb). These discrepancies can be generally solved using two different approaches, either by involvement of a component of specific chemical composition, or by considering elemental fractionation during tektite formation. The proposed conceptual model of moldavite formation combines both approaches and is based on several steps: (i) the parent mixture (Upper Freshwater Molasse sediments as the dominant source) contained also a minor admixture of organic matter and soils; (ii) the most energetic part of the ejected matter was converted to vapor (plasma) and another part produced melt directly upon decompression; (iii) following further adiabatic decompression, the expanding vapor phase disintegrated the melt into small melt droplets and some elements were partially lost from the melt because of their volatility, or because of the volatility of their compounds, such as carbonyls of Fe and other transition metals (e.g., Ni, Co, Mo, Cr, and Cu); (iv) large positively charged ions such as Cs+, Ba2+, K+, Rb+ from the plasma portion were enriched in the late-stage condensation spherules or condensed

  9. Suevite superposition on the Bunte breccia in Noerdlinger Ries, Germany: New findings on the transport mechanism of impactites

    NASA Technical Reports Server (NTRS)

    Bringemeier, D.

    1992-01-01

    Research undertaken in the last decades in Noerdlinger Ries, Germany, has repeatedly emphasized the sharp contact between Bunte breccia and suevite. However, extensive investigations into this layer boundary have not yet been possible due to insufficient outcrop ratios. New outcrops enabled an in-depth investigation into the superposition of suevite on the Bunte breccia, which is assigned a key role in interpreting the transport mechanisms of ejecta of large impact. In two quarries lying several kilometers east and south-southwest of the crater, the contact between the suevite and Bunte breccia was recorded in detailed sections on outcrops of over 50 m in length.

  10. Fluidization and hydrothermal alteration of the suevite deposit at the Ries Crater, West Germany, and implications for Mars

    NASA Technical Reports Server (NTRS)

    Newsom, Horton E.; Sewards, Terry; Keil, Klaus; Graup, Guenther

    1986-01-01

    The emplacement, cooling, and alteration of the suevite at the Ries Crater are discussed. The clay mineralogy of the suevite is examined in terms of the cooling of the suevite and the importance of hydrothermal alteration. It is observed that the suevite contains large number of chimneylike degassing pipes, and that the suevite outside of the crater rim contains about 15 wt pct clay. The vertical channels or degassing pipes related to the fall-out of suevite are described. The relationship between the formation of the impact deposits on earth and Mars and the origin of Martian soil, and the emplacement and alteration of impact ejecta is studied.

  11. The Science of Battery Degradation

    SciTech Connect

    Sullivan, John P.; El Gabaly Marquez, Farid; McCarty, Kevin; Sugar, Joshua Daniel; Talin, Alec A.; Fenton, Kyle R.; Nagasubramanian, Ganesan; Harris, Charles Thomas; Kliewer, Christopher Jesse; Hudak, Nicholas S.; Leung, Kevin; McDaniel, Anthony H.; Tenney, Craig M.; Zavadil, Kevin R.

    2015-01-01

    This report documents work that was performed under the Laboratory Directed Research and Development project, Science of Battery Degradation. The focus of this work was on the creation of new experimental and theoretical approaches to understand atomistic mechanisms of degradation in battery electrodes that result in loss of electrical energy storage capacity. Several unique approaches were developed during the course of the project, including the invention of a technique based on ultramicrotoming to cross-section commercial scale battery electrodes, the demonstration of scanning transmission x-ray microscopy (STXM) to probe lithium transport mechanisms within Li-ion battery electrodes, the creation of in-situ liquid cells to observe electrochemical reactions in real-time using both transmission electron microscopy (TEM) and STXM, the creation of an in-situ optical cell utilizing Raman spectroscopy and the application of the cell for analyzing redox flow batteries, the invention of an approach for performing ab initio simulation of electrochemical reactions under potential control and its application for the study of electrolyte degradation, and the development of an electrochemical entropy technique combined with x-ray based structural measurements for understanding origins of battery degradation. These approaches led to a number of scientific discoveries. Using STXM we learned that lithium iron phosphate battery cathodes display unexpected behavior during lithiation wherein lithium transport is controlled by nucleation of a lithiated phase, leading to high heterogeneity in lithium content at each particle and a surprising invariance of local current density with the overall electrode charging current. We discovered using in-situ transmission electron microscopy that there is a size limit to lithiation of silicon anode particles above which particle fracture controls electrode degradation. From electrochemical entropy measurements, we discovered that entropy

  12. Electrical injury

    MedlinePlus

    ... damage, especially to the heart, muscles, or brain. Electric current can cause injury in three ways: Cardiac arrest ... How long you were in contact with the electricity How the electricity moved through your body Your ...

  13. Electricity Customers

    EPA Pesticide Factsheets

    This page discusses key sectors and how they use electricity. Residential, commercial, and industrial customers each account for roughly one-third of the nation’s electricity use. The transportation sector also accounts for a small fraction of electricity.

  14. MaRIE 1.0: The Matter-Radiation Interactions in Extremes Project, and the Challenge of Dynamic Mesoscale Imaging

    SciTech Connect

    Barnes, Cris William; Barber, John L.; Kober, Edward Martin; Lookman, Turab; Sandberg, Richard L.; Shlachter, Jack S.; Sheffield, Richard L.

    2015-02-23

    The Matter-Radiation Interactions in Extremes project will build the experimental facility for the time-dependent control of dynamic material performance. An x-ray free electron laser at up to 42-keV fundamental energy and with photon pulses down to sub-nanosecond spacing, MaRIE 1.0 is designed to meet the challenges of time-dependent mesoscale materials science. Those challenges will be outlined, the techniques of coherent diffractive imaging and dynamic polycrystalline diffraction described, and the resulting requirements defined for a coherent x-ray source. The talk concludes with the role of the MaRIE project and science in the future.

  15. Evaluation of Fuel Cell Operation and Degradation

    SciTech Connect

    Williams, Mark; Gemmen, Randall; Richards, George

    2011-06-01

    The concepts of area specific resistance (ASR) and degradation are developed for different fuel cell operating modes. The concepts of exergetic efficiency and entropy production were applied to ASR and degradation. It is shown that exergetic efficiency is a time-dependent function useful describing the thermal efficiency of a fuel cell and the change in thermal efficiency of a degrading fuel cell. Entropy production was evaluated for the cases of constant voltage operation and constant current operation of the fuel cell for a fuel cell undergoing ohmic degradation. It was discovered that the Gaussian hypergeometric function describes the cumulative entropy and electrical work produced by fuel cells operating at constant voltage. The Gaussian hypergeometric function is found in many applications in modern physics. This paper builds from and is an extension of several papers recently published by the authors in the Journal of The Electrochemical Society (ECS), ECS Transactions, Journal of Power Sources, and the Journal of Fuel Cell Science and Technology.

  16. Effect of interface characteristics on electrical properties of metal-gallium nitride heterostructures

    NASA Astrophysics Data System (ADS)

    Kim, Ho Gyoung

    The electrical properties of metal-GaN heterostructures due to the defects and nanoscale surface inhomogeneities have been characterized to explore the nature of electron transport and the feasibility of device fabrication. The effect of nanoscale Pt islands on the contact resistivity and Schottky barrier height in Al/p-GaN contacts was investigated. It was shown that the Al contact with nanoscale Pt islands produced good ohmic characteristics and high reflectance. Current-voltage-temperature (I-V-T) measurements in combination with modeling showed that the electric field enhancement and the increase of the possibility of tunneling due to the nanoscale Pt islands result in an improved ohmic contact. Electrical transport in nanopatterned contacts to n-GaN using porous anodic alumina (PAA) films as masks was investigated. Non-linear I-V characteristics for the as-grown samples became linear for the reactive ion etched (RIE) and PAA patterned samples. Significant reduction of the specific contact resistivity and the effective barrier height and an increase in the reverse current were observed in the PAA patterned sample. The reduction of the depletion width at sharp corners enhanced the local tunneling current, reducing the specific contact resistivity and decreasing the effective barrier height. The electrical properties of surface treatments such as KOH treatment and laser etching in unintentionally doped GaN were investigated. KOH treatment produced an increase in the Schottky barrier height and a decrease in the reverse leakage current. By fitting I-V data in the reverse bias region based on the thermionic field emission (TFE) model, it was shown that the experimental results are consistent with the presence of high densities of surface states, which were reduced appreciably by the KOH treatment. Laser etching yielded an increase of interface trap density and degraded the rectifying I-V characteristics. Post-treatment for the laser etched samples with thermal

  17. Electrical Curriculum.

    ERIC Educational Resources Information Center

    EASTCONN Regional Educational Services Center, North Windham, CT.

    The purpose of this electrical program is to prepare students for service, repair, and assembly of electrically driven or controlled devices. The program theory and application includes mechanical assemblies, electrical circuitry, and electronic principles including basic digital circuitry. The electrical program manual includes the following…

  18. The Ries impact crater described as an analogue for a Martian double-layered ejecta crater on Earth

    NASA Astrophysics Data System (ADS)

    Sturm, Sebastian; Wulf, Gerwin; Jung, Dietmar; Kenkmann, Thomas

    2014-05-01

    The Ries impact crater (~26 km-diameter) is described as a relatively pristine, complex impact crater in southern Germany. The oblique impact occurred during the Miocene (14.9 Ma) and hit into a two-layered target material that consists of ~650 m partly water-saturated and subhorizontally layered sediments (limestones, sandstones, shales) of Triassic to Tertiary ages underlain by crystalline basement rocks (mainly gneisses, granites and amphibolites) [1, 2, 3, 4]. The continuous and well-preserved ejecta blanket reaches up to a distance of 45 km from the crater center. It is built up by so called Bunte Breccia material that is described as a polymict lithic breccia. Bunte Breccia mainly consists of unshocked to weakly shocked sedimentary target clasts including a minority of crystalline basement clasts and reworked surfical sediments (e.g., Upper Freshwater Molasses or Upper Seawater Molasses) [5, 6]. Here we present our final interpolation results of the morphology of the paleo-surface and the thickness variations of the continuous ejecta blanket (Bunte Breccia) with radial range outside of the Ries impact crater. Our results were then compared with ejecta distribution characteristics of Martian complex double-layered ejecta craters (DLE) [7]. We combined digital elevation data (ASTER DEM) and geologic information of the recent geologic map [8], in addition with nine NASA Drillings [6], and up to 40 Bavarian Environment Agency drillings in ArcGIS (ESRI) and RockWorks14 (RockWare) to interpolate the elevation of the lower contact plane ("paleo-surface") and the contact between the Bunte breccia and the overlain Suevite deposits to reconstruct the Bunte Breccia thickness variation outside of the Ries impact crater [7]. Our final interpolation results of the paleo-surface and Bunte Breccia top surface provide an increasing Bunte breccia thickness with increasing distance from the crater center. The ejecta thickness distribution clearly deviates from a steady decrease

  19. Targeted polypeptide degradation

    DOEpatents

    Church, George M.; Janse, Daniel M.

    2008-05-13

    This invention pertains to compositions, methods, cells and organisms useful for selectively localizing polypeptides to the proteasome for degradation. Therapeutic methods and pharmaceutical compositions for treating disorders associated with the expression and/or activity of a polypeptide by targeting these polypeptides for degradation, as well as methods for targeting therapeutic polypeptides for degradation and/or activating therapeutic polypeptides by degradation are provided. The invention provides methods for identifying compounds that mediate proteasome localization and/or polypeptide degradation. The invention also provides research tools for the study of protein function.

  20. The fate of moderately volatile elements in impact events—Lithium connection between the Ries sediments and central European tektites

    NASA Astrophysics Data System (ADS)

    Rodovská, Zuzana; Magna, Tomáš; Žák, Karel; Skála, Roman; Brachaniec, Tomasz; Visscher, Channon

    2016-12-01

    Lithium abundances and isotope compositions are presented for a suite of sediments from the surroundings of the Ries Impact structure, paralleled by new Li data for central European tektites (moldavites) from several substrewn fields (South Bohemia, Moravia, Cheb Basin, Lusatia), including a specimen from the newly discovered substrewn field in Poland. The data set was supplemented by three clay fractions isolated from sedimentary samples. Moldavites measured in this study show a very narrow range in δ7Li values (-0.6 to 0.3‰ relative to L-SVEC) and Li contents (23.9-48.1 ppm). This contrasts with sediments from the Ries area which show remarkable range in Li isotope compositions (from -6.9 to 13.4‰) and Li contents (0.6-256 ppm). The OSM sediments which, based on chemical similarity, formed the major part of moldavites, show a range in δ7Li values from -2.0 to 7.9‰ and Li contents from 5.8 to 78.9 ppm. Therefore, the formation of moldavites was apparently accompanied by large-scale mixing, paralleled by chemical and isotope homogenization of their parent matter. The proposed Li mixing model indicates that sands, clayey sediments, and low volumes of carbonates are the major components for tektite formation whereas residual paleokarst sediments could have been a minor but important component for a subset of moldavites. Striking homogenization of Li in tektites, combined with limited Li loss during impacts, may suggest that moderately volatile elements are not scavenged and isotopically fractionated during large-scale collisions, which is consistent with recent models. In general, whether homogenization of bodies with distinct Li isotope systematics takes place, or collision of bodies with similar Li systematics operates cannot be resolved at present stage but Li isotope homogeneity of solar system planets and asteroidal bodies tentatively implies the latter.

  1. Self-aligned single-mask fabrication process for electro-thermal microactuators using ICP-RIE

    NASA Astrophysics Data System (ADS)

    Alamin Dow, Ali B.; Gougam, Adel; Kherani, Nazir P.; Rangelow, I. W.

    2013-05-01

    Advances in the miniaturization of semiconductor devices have been made possible by new methods of microfabrication techniques . These advances have stimulated the birth of Micro Electro Mechanical Systems (MEMS) technology which enable the fabrication of a wide variety of sensing and actuating devices of microscopic dimensions . Of particular interest are thermal microactuators which provide large deflections and are compatible with existing IC technologies. In MEMS technology, a well controlled etching process is critical for the fabrication of structures with specific geometry and properties. Increasing demand for intricate semiconductor devices has fueled and motivated researches to develop high precision micromachining techniques . Inductively coupled plasma- Reactive ion etching (ICP-RIE) is capable of producing features with high aspect ratio as high as 90:1. Taking advantage of the notching effect when making a structure from silicon on insulator (SOI), structure release without the use of HF acid has been demonstrated. We report on the development of a self-aligned single-mask process for the fabrication of released and movable MEMS devices. ICP-RIE was used to realize the structures directly out of single crystal silicon. Applying side wall passivation, controlling the ratio of ion flux and radical flux, smooth etching profile can be obtained with high aspect ratio. No wet etching process is required to release the structures as is the case with SOI wafers. This approach overcomes the stiction limitation associated with wet etching and yields good thickness uniformity over the entire structure. Electrothermal microactuators with integrated microgrippers were designed, fabricated and characterized. harvesters.

  2. Determination of efficiencies, loss mechanisms, and performance degradation factors in chopper controlled dc vehical motors. Section 2: The time dependent finite element modeling of the electromagnetic field in electrical machines: Methods and applications. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Hamilton, H. B.; Strangas, E.

    1980-01-01

    The time dependent solution of the magnetic field is introduced as a method for accounting for the variation, in time, of the machine parameters in predicting and analyzing the performance of the electrical machines. The method of time dependent finite element was used in combination with an also time dependent construction of a grid for the air gap region. The Maxwell stress tensor was used to calculate the airgap torque from the magnetic vector potential distribution. Incremental inductances were defined and calculated as functions of time, depending on eddy currents and saturation. The currents in all the machine circuits were calculated in the time domain based on these inductances, which were continuously updated. The method was applied to a chopper controlled DC series motor used for electric vehicle drive, and to a salient pole sychronous motor with damper bars. Simulation results were compared to experimentally obtained ones.

  3. Epidemiological Analysis of Degradation in Silicon Photovoltaic Modules

    NASA Astrophysics Data System (ADS)

    Sakamoto, Sadao; Kobayashi, Tomonao; Nonomura, Shuichi

    2012-10-01

    We have studied the power reduction rate and degradation modes of crystalline-silicon photovoltaic modules, which had been operated in an outdoor field for about 10 years. We measured the electric parameters of the modules before and after 10-year operation, and classified our photovoltaic modules into four groups that were manufactured by four manufacturers. Analyzing the age-related decreases in electric parameters of the modules, we found two dominant degradation modes by correlation analysis of the electric parameters. In addition, we found delamination mode degradation by visual inspection. We have recognized a degradation rate in terms of the statistical distribution of the module power reduction. The power reduction rate was found to be an average of 4.7% for ten years.

  4. Analytical predictions of selenide RTG power degradation

    NASA Technical Reports Server (NTRS)

    Noon, E. L.; Stapfer, G.; Raag, V.

    1978-01-01

    A mathematical model for the performance and degradation analysis of an RTG using the newly developed selenide thermoelectric materials has been developed at JPL. The computerized model is quite comprehensive and enables the accurate detailing of the electrical and thermal effects that take place within the thermocouple under any desired set of operation conditions, including heat input, ambient temperature and load conditions. The paper discusses the logic flow of the computer model and presents the time and temperature dependent results for various degradation mechanisms and rates as they have been established to date.

  5. Evaluation of the performance degradation at PAFC effect of catalyst degradation on electrode performance

    SciTech Connect

    Nishizaki, K.; Uchida, H.; Watanabe, M.

    1996-12-31

    Aiming commercialization of Phosphoric Acid Fuel Cell (PAFC) power plant, many researches and developments have been contributed. Over 20000 hours operations have been demonstrated by many PAFC power plants. But there is no effective method for the estimation of lifetime of electrochemical cells without a practical long-term operation. Conducted by New Energy and Industrial Technology Development Organization (NEDO), cooperative research projects aiming development of PAFC lifetime estimation method have started since 1995 FY in Japan. As part of this project, this work has been performed to clarify basic phenomena of the performance degradation at PAFCs jointly by Yamanashi University, Phosphoric Acid Fuel Cell Technology Research Association (PAFC-TRA) and PAFC manufacturers (Toshiba Co., Mitsubishi Electric Co, Fuji Electric Co.). Among several main causes of the cell performance degradation, effects of catalyst degradation (reduction in metal surface area, dealloying, changes in catalyst support) on PAFC cathode performances are discussed in this work.

  6. Electrical Generation.

    ERIC Educational Resources Information Center

    Science and Children, 1990

    1990-01-01

    Described are two activities designed to help children investigate electrical charges, electric meters, and electromagnets. Included are background information, a list of materials, procedures, and follow-up questions. Sources of additional information are cited. (CW)

  7. Processing-Induced Electrically Active Defects in Black Silicon Nanowire Devices.

    PubMed

    Carapezzi, Stefania; Castaldini, Antonio; Mancarella, Fulvio; Poggi, Antonella; Cavallini, Anna

    2016-04-27

    Silicon nanowires (Si NWs) are widely investigated nowadays for implementation in advanced energy conversion and storage devices, as well as many other possible applications. Black silicon (BSi)-NWs are dry etched NWs that merge the advantages related to low-dimensionality with the special industrial appeal connected to deep reactive ion etching (RIE). In fact, RIE is a well established technique in microelectronics manufacturing. However, RIE processing could affect the electrical properties of BSi-NWs by introducing deep states into their forbidden gap. This work applies deep level transient spectroscopy (DLTS) to identify electrically active deep levels and the associated defects in dry etched Si NW arrays. Besides, the successful fitting of DLTS spectra of BSi-NWs-based Schottky barrier diodes is an experimental confirmation that the same theoretical framework of dynamic electronic behavior of deep levels applies in bulk as well as in low dimensional structures like NWs, when quantum confinement conditions do not occur. This has been validated for deep levels associated with simple pointlike defects as well as for deep levels associated with defects with richer structures, whose dynamic electronic behavior implies a more complex picture.

  8. Hydroxyapatite degradation and biocompatibility

    NASA Astrophysics Data System (ADS)

    Wang, Haibo

    Hydroxyapatite (HA) is widely used as a bioactive ceramics since it forms a chemical bonding to bone. The disadvantage of this material is its poor mechanical properties. HA can be degraded in body, which is the reason for its bioactivity, but too fast degradation rate could cause negative effects, such as macrophage present, particle generation, and even implant clinical failure. HA degradation rate will be greatly changed under many conditions: purity, HA form (i.e. bulk form, porous form, coating, or HA/polymer composites), microstructure, implant site, body conditions, etc. Although much work has been done in HA properties and application areas, the HA degradation behavior and mechanism under these different conditions are still not clear. In this research, three aspects of HA degradation have been studied: (1) Two very common impurities---Tri-Calcium Phosphate (TCP) and Calcium Oxide and their influences on HA degradation in vitro and in vivo, (2) influence of HA/polymer composite form on HA degradation, (3) HA material particle generation and related mechanism. From the in vitro and in vivo tests on bulk HA disks with various Ca/P ratios, HA degradation can clearly be found. The degradation level is different in different Ca/P ratio samples as well as in different test environments. In same test environment, non-stoichiometric HA samples have higher degradation rate than stoichiometric HA. HA/PMMA composite design successfully intensifies HA degradation both in vitro and in vivo. Grain boundary damage can be found on in vivo test samples, which has not been clearly seen on bulk HA degraded surface. HA particle generation is found in in vitro and in vivo HA/PMMA composite surface and in vivo bulk HA surface. Sintering temperature and time does affect HA grain size, and this affect HA degradation rate. Intergranular fracture is found in a several micron zone close to the Ca/P ratio 1.62 and 1.67 sample degraded surfaces. At Ca/P ratio greater than 1.667, after

  9. Degradations and Rearrangement Reactions

    NASA Astrophysics Data System (ADS)

    Zhang, Jianbo

    This section deals with recent reports concerning degradation and rearrangement reactions of free sugars as well as some glycosides. The transformations are classified in chemical and enzymatic ways. In addition, the Maillard reaction will be discussed as an example of degradation and rearrangement transformation and its application in current research in the fields of chemistry and biology.

  10. Batteries: Imaging degradation

    NASA Astrophysics Data System (ADS)

    Shearing, Paul R.

    2016-11-01

    The degradation and failure of Li-ion batteries is strongly associated with electrode microstructure change upon (de)lithiation. Now, an operando X-ray tomography approach is shown to correlate changes in the microstructure of electrodes to cell performance, and thereby predict degradation pathways.

  11. Electric vehicles

    NASA Astrophysics Data System (ADS)

    1990-03-01

    Quiet, clean, and efficient, electric vehicles (EVs) may someday become a practical mode of transportation for the general public. Electric vehicles can provide many advantages for the nation's environment and energy supply because they run on electricity, which can be produced from many sources of energy such as coal, natural gas, uranium, and hydropower. These vehicles offer fuel versatility to the transportation sector, which depends almost solely on oil for its energy needs. Electric vehicles are any mode of transportation operated by a motor that receives electricity from a battery or fuel cell. EVs come in all shapes and sizes and may be used for different tasks. Some EVs are small and simple, such as golf carts and electric wheel chairs. Others are larger and more complex, such as automobile and vans. Some EVs, such as fork lifts, are used in industries. In this fact sheet, we will discuss mostly automobiles and vans. There are also variations on electric vehicles, such as hybrid vehicles and solar-powered vehicles. Hybrid vehicles use electricity as their primary source of energy, however, they also use a backup source of energy, such as gasoline, methanol or ethanol. Solar-powered vehicles are electric vehicles that use photovoltaic cells (cells that convert solar energy to electricity) rather than utility-supplied electricity to recharge the batteries. These concepts are discussed.

  12. DEA degradation mechanism

    SciTech Connect

    Meisen, A.; Kennard, M.L.

    1982-10-01

    Examines factors that increase diethanolamine (DEA) degradation, which reportedly depends on temperature, pressure, gas composition, amine concentration, pH of the amine solution and the presence of metal ions. Plant operators have tried to solve the problem by changing operating conditions and/or installing activated carbon filters. DEA degradation is frequently experienced in gas plants used for removing acidic gases such as carbon dioxide and hydrogen sulfide from light hydrocarbons. Experimental results reveal that degradation is governed by: solubility of CO/sub 2/ in the DEA solution; degree of dissociation of the DEA molecules in solution; interaction of DEA and CO/sub 2/ molecules and/or ionic complexes. Most, or all, these phenomena are affected by temperature, pressure, DEA concentration and pH. A series of tests to determine whether activated carbon is capable of removing impurities from partially degraded DEA solutions showed that this treatment did not remove any major degradation compounds from the solutions.

  13. Degradation Kinetics of VX

    SciTech Connect

    Gary S. Groenewold

    2010-12-01

    O-ethyl S-(2-diisopropylaminoethyl)phosphonothiolate (VX) is the most toxic of the conventional chemical warfare agents. It is a persistent compound, an attribute derived from its relative involatility and slow rates of hydrolysis. These properties suggest that VX can linger in an exposed environment for extended periods of time long after the air has cleared. Concern over prolonged risk from VX exposure is exacerbated by the fact that it poses a dermal contact hazard. Hence a detailed understanding of volatilization rates, and degradation pathways and rates occurring in various environments is needed. Historically, volatilization has not been considered to be an important mechanism for VX depletion, but recent studies have shown that a significant fraction of VX may volatilize, depending on the matrix. A significant body of research has been conducted over the years to unravel VX degradation reaction pathways and to quantify the rates at which they proceed. Rigorous measurement of degradation rates is frequently difficult, and thus in many cases the degradation of VX has been described in terms of half lives, while in fewer instances rate constants have been measured. This variable approach to describing degradation kinetics reflects uncertainty regarding the exact nature of the degradation mechanisms. In this review, rates of VX degradation are compared on the basis of pseudo-first order rate constants, in order to provide a basis for assessing likelihood of VX persistence in a given environment. An issue of specific concern is that one VX degradation pathway produces S-2-(diisopropylaminoethyl) methylphosphonothioic acid (known as EA2192), which is a degradation product that retains much of the original toxicity of VX. Consequently degradation pathways and rates for EA2192 are also discussed.

  14. Septicémie fatale due à une bactérie émergente: arcanobactrium hemolyticum

    PubMed Central

    Frikh, Mohammed; Lemouer, Abdelhay; Moutawakil, Mustapha; Maleb, Adil; Elouennass, Mostafa

    2016-01-01

    L’Arcanobactérium haemolyticum (A.haemolyticum) est un bacille à Gram positif. L’homme en est le principal réservoir. C’est un pathogène opportuniste essentiellement chez l’immunodéprimé, et qui peut être responsable d’infection au niveau de la peau et du pharynx chez les sujets sains, surtout chez les enfants et les adolescents. Il peut causer des surinfections des ulcères chroniques, et occasionnellement des infections invasives. Sa détection au niveau des cultures reste toujours difficile car il simule de nombreuses bactéries auxquelles il est souvent associé dans les produits pathologiques. Et Il n’existe pas de recommandations concernant l’étude sa sensibilité aux antibiotiques. Les bactériémies à Arcanobactérium sont rares, à notre connaissance, seize cas ont été décrits dans la littérature. Nous rapportons, un autre cas de bactériémie à A.haemolyticum, secondaire à une surinfection d’escarres fessières. PMID:28154720

  15. MaRIE 1.0: A briefing to Katherine Richardson-McDaniel, Staff Member for U. S. Senator Martin Heinrich (D-NM)

    SciTech Connect

    Barnes, Cris William

    2015-02-24

    At the request of Katherine Richardson-McDaniel, Staff Member to U.S. Senator Martin Heinrich (D-NM), a high-level briefing was requested about MaRIE 1.0, the Matter-Radiation Interactions in Extremes effort at Los Alamos National Laboratory. What it would be, the mission need motivation, the scientific challenge, and the current favorable impact on both programs and people are shown in viewgraph form.

  16. INTERMITTENT DEGRADATION AND SCHIZOTYPY.

    PubMed

    Roché, Matthew W; Silverstein, Steven M; Lenzenweger, Mark F

    2015-06-01

    Intermittent degradation refers to transient detrimental disruptions in task performance. This phenomenon has been repeatedly observed in the performance data of patients with schizophrenia. Whether intermittent degradation is a feature of the liability for schizophrenia (i.e., schizotypy) is an open question. Further, the specificity of intermittent degradation to schizotypy has yet to be investigated. To address these questions, 92 undergraduate participants completed a battery of self-report questionnaires assessing schizotypy and psychological state variables (e.g., anxiety, depression), and their reaction times were recorded as they did so. Intermittent degradation was defined as the number of times a subject's reaction time for questionnaire items met or exceeded three standard deviations from his or her mean reaction time after controlling for each item's information processing load. Intermittent degradation scores were correlated with questionnaire scores. Our results indicate that intermittent degradation is associated with total scores on measures of positive and disorganized schizotypy, but unrelated to total scores on measures of negative schizotypy and psychological state variables. Intermittent degradation is interpreted as potentially derivative of schizotypy and a candidate endophenotypic marker worthy of continued research.

  17. Evidence of the impacting body of the Ries crater - the discovery of Fe-Cr-Ni veinlets below the crater bottom

    USGS Publications Warehouse

    El, Goresy A.; Chao, E.C.T.

    1976-01-01

    Fe-Cr-Ni particles and veinlets have been discovered in the top 15 m of the compressed zone with abundant shatter cones below the bottom of the Ries crater. The metallic particles are less than a few microns across. They occur in various minerals along healed intergranular and locally in intragranular microfractures in quartz diorite, amphibolite and chloritized granite of the basement crystalline rocks. The particles consist of major Fe, Cr, and Ni with minor Si and Ca. Origin due to contamination is absolutely ruled out. We believe that these Fe-Cr-Ni particles are probably condensed from the vaporized impacting body which produced the Ries crater. These particles were injected with high velocity into microfractures near the top of the compressed zone, implanted in and across various minerals before these microfractures were resealed. The presence of Si and Ca as well as the fact that the Cr content is nearly twice that of Ni, led us to conclude that the Ries impacting body is very likely not an iron meteorite but a stony meteorite. ?? 1976.

  18. Electrical stator

    DOEpatents

    Fanning, Alan W.; Olich, Eugene E.

    1994-01-01

    An electrical stator of an electromagnetic pump includes first and second spaced apart coils each having input and output terminals for carrying electrical current. An elongate electrical connector extends between the first and second coils and has first and second opposite ends. The connector ends include respective slots receiving therein respective ones of the coil terminals to define respective first and second joints. Each of the joints includes a braze filler fixedly joining the connector ends to the respective coil terminals for carrying electrical current therethrough.

  19. Electric propulsion

    NASA Astrophysics Data System (ADS)

    Garrison, Philip W.

    Electric propulsion (EP) is an attractive option for unmanned orbital transfer vehicles (OTV's). Vehicles with solar electric propulsion (SEP) could be used routinely to transport cargo between nodes in Earth, lunar, and Mars orbit. Electric propulsion systems are low-thrust, high-specific-impulse systems with fuel efficiencies 2 to 10 times the efficiencies of systems using chemical propellants. The payoff for this performance can be high, since a principal cost for a space transportation system is that of launching to low Earth orbit (LEO) the propellant required for operations between LEO and other nodes. Several aspects of electric propulsion, including candidate systems and the impact of using nonterrestrial materials, are discussed.

  20. Degradation of chlorpyrifos in tropical rice soils.

    PubMed

    Das, Subhasis; Adhya, Tapan K

    2015-04-01

    Chlorpyrifos [O,O-diethyl O-(3,5,6-trichloro-2-pyridinol) phosphorothioate] is used worldwide as an agricultural insecticide against a broad spectrum of insect pests of economically important crops including rice, and soil application to control termites. The insecticide mostly undergoes hydrolysis to diethyl thiophosphoric acid (DETP) and 3,5,6-trichloro-2-pyridinol (TCP), and negligible amounts of other intermediate products. In a laboratory-cum-greenhouse study, chlorpyrifos, applied at a rate of 10 mg kg(-1) soil to five tropical rice soils of wide physico-chemical variability, degraded with a half-life ranging from 27.07 to 3.82 days. TCP was the major metabolite under both non-flooded and flooded conditions. Chlorpyrifos degradation had significant negative relationship with electrical conductivity (EC), cation exchange capacity (CEC), clay and sand contents of the soils under non-flooded conditions. Results indicate that degradation of chlorpyrifos was accelerated with increase in its application frequency, across the representative rice soils. Management regimes including moisture content and presence or absence of rice plants also influenced the process. Biotic factors also play an important role in the degradation of chlorpyrifos as demonstrated by its convincing degradation in mineral salts medium inoculated with non-sterile soil suspension.

  1. Re-validation of the Van Rie HIV/AIDS-related stigma scale for use with people living with HIV in the United States.

    PubMed

    Kipp, Aaron M; Audet, Carolyn M; Earnshaw, Valerie A; Owens, Jared; McGowan, Catherine C; Wallston, Kenneth A

    2015-01-01

    There is little consensus about which of the many validated human immunodeficiency virus (HIV) stigma scales should be regularly used, with few being re-validated in different contexts or evaluated for how they compare to other, existing HIV stigma scales. The purpose of this exploratory study was to re-validate the Van Rie HIV/AIDS-Related Stigma Scale, originally validated in Thailand and using a third-person wording structure, for use with people living with HIV in the United States. Adult HIV clinic patients completed a survey including the Berger and Van Rie scales, and measures of social support and depression. Eighty-five of 211 (40%) eligible participants provided data for both stigma scales. Exploratory factor analyses identified three factors to the Van Rie scale: Loss of Social Relationships (new subscale), Managing HIV Concealment (new subscale), and Perceived Community Stigma (original subscale). These subscales were moderately inter-related (r = 0.51 to 0.58) with acceptable to excellent reliability (Cronbach's alpha = 0.69 to 0.90). The Van Rie subscales were also moderately inter-correlated with the Berger subscales (r = 0.44 to 0.76), had similar construct validity, and tended to have higher mean stigma scores when compared with Berger subscales that were conceptually most similar. The revised Van Rie HIV-related Stigma Scale demonstrates good validity and internal consistency, offering a valid measure of HIV stigma with a three-factor structure. The third-person wording may be particularly suitable for measuring stigmatizing attitudes during an individual's transition from at-risk and undergoing HIV testing to newly diagnosed, a time when experiences of discrimination and processing issues of disclosure have not yet occurred. The stigma mechanisms for individuals making this transition have not been well explored. These scenarios, combined with the observed non-response to the Berger Enacted Stigma subscale items (a surprise finding), highlight

  2. Salvage chemoimmunotherapy with rituximab, ifosfamide and etoposide (R-IE regimen) in patients with primary CNS lymphoma relapsed or refractory to high-dose methotrexate-based chemotherapy.

    PubMed

    Mappa, Silvia; Marturano, Emerenziana; Licata, Giada; Frezzato, Maurizio; Frungillo, Niccolò; Ilariucci, Fiorella; Stelitano, Caterina; Ferrari, Antonella; Sorarù, Mariella; Vianello, Fabrizio; Baldini, Luca; Proserpio, Ilaria; Foppoli, Marco; Assanelli, Andrea; Reni, Michele; Caligaris-Cappio, Federico; Ferreri, Andrés J M

    2013-09-01

    Despite a high proportion of patients with primary CNS lymphoma (PCNSL) experiences failure after/during first-line treatment, a few studies focused on salvage therapy are available, often with disappointing results. Herein, we report feasibility and activity of a combination of rituximab, ifosfamide and etoposide (R-IE regimen) in a multicentre series of patients with PCNSL relapsed or refractory to high-dose methotrexate-based chemotherapy. We considered consecutive HIV-negative patients ≤75 years old with failed PCNSL treated with R-IE regimen (rituximab 375 mg/m(2) , day 0; ifosfamide 2 g/m(2) /day, days1-3; etoposide 250 mg/m(2) , day 1; four courses). Twenty-two patients (median age 60 years; range 39-72; male/female ratio: 1:4) received R-IE as second-line (n = 18) or third-line (n = 4) treatment. Eleven patients had refractory PCNSL, and 11 had relapsing disease. Twelve patients had been previously irradiated. Sixty (68%) of the 88 planned courses were actually delivered; only one patient interrupted R-IE because of toxicity. Grade 4 hematological toxicity was manageable; a single case of grade 4 non-hematological toxicity (transient hepatotoxicity) was recorded. Response was complete in six patients and partial in three (overall response rate = 41%; 95%CI: 21-61%). Seven patients were successfully referred to autologous peripheral blood stem cell collection; four responders were consolidated with high-dose chemotherapy supported by autologous stem cell transplant. At a median follow-up of 24 months, eight responders did not experience relapse, two of them died of neurological impairment while in remission. Six patients are alive, with a 2-year survival after relapse of 25 ± 9%. We concluded that R-IE is a feasible and active combination for patients with relapsed/refractory PCNSL. This regimen allows stem cell collection and successful consolidation with high-dose chemotherapy and autologous transplant.

  3. Polyanhydride degradation and erosion.

    PubMed

    Göpferich, A; Tessmar, J

    2002-10-16

    It was the intention of this paper to give a survey on the degradation and erosion of polyanhydrides. Due to the multitude of polymers that have been synthesized in this class of material in recent years, it was not possible to discuss all polyanhydrides that have gained in significance based on their application. It was rather the intention to provide a broad picture on polyanhydride degradation and erosion based on the knowledge that we have from those polymers that have been intensively investigated. To reach this goal this review contains several sections. First, the foundation for an understanding of the nomenclature are laid by defining degradation and erosion which was deemed necessary because many different definitions exist in the current literature. Next, the properties of major classes of anhydrides are reviewed and the impact of geometry on degradation and erosion is discussed. A complicated issue is the control of drug release from degradable polymers. Therefore, the aspect of erosion-controlled release and drug stability inside polyanhydrides are discussed. Towards the end of the paper models are briefly reviewed that describe the erosion of polyanhydrides. Empirical models as well as Monte-Carlo-based approaches are described. Finally it is outlined how theoretical models can help to answer the question why polyanhydrides are surface eroding. A look at the microstructure and the results from these models lead to the conclusion that polyanhydrides are surface eroding due to their fast degradation. However they switch to bulk erosion once the device dimensions drop below a critical limit.

  4. Electric machine

    DOEpatents

    El-Refaie, Ayman Mohamed Fawzi [Niskayuna, NY; Reddy, Patel Bhageerath [Madison, WI

    2012-07-17

    An interior permanent magnet electric machine is disclosed. The interior permanent magnet electric machine comprises a rotor comprising a plurality of radially placed magnets each having a proximal end and a distal end, wherein each magnet comprises a plurality of magnetic segments and at least one magnetic segment towards the distal end comprises a high resistivity magnetic material.

  5. Teaching Electricity.

    ERIC Educational Resources Information Center

    Iona, Mario

    1982-01-01

    To clarify the meaning of electrical terms, a chart is used to compare electrical concepts and relationships with a more easily visualized system in which water flows from a hilltop reservoir through a pipe to drive a mill at the bottom of the hill. A diagram accompanies the chart. (Author/SK)

  6. DDE remediation and degradation.

    PubMed

    Thomas, John E; Ou, Li-Tse; All-Agely, Abid

    2008-01-01

    DDT and its metabolites, DDD and DDE, have been shown to be recalcitrant to degradation. The parent compound, DDT, was used extensively worldwide starting in 1939 and was banned in the United States in 1973. The daughter compound, DDE, may result from aerobic degradation, abiotic dehydrochlorination, or photochemical decomposition. DDE has also occurred as a contaminant in commercial-grade DDT. The p,p'-DDE isomer is more biologically active than the o,p-DDE, with a reported half-life of -5.7 years. However, when DDT was repeatedly applied to the soil, the DDE concentration may remain unchanged for more than 20 yr. Remediation of DDE-contaminated soil and water may be done by several techniques. Phytoremediation involves translocating DDT, DDD, and DDE from the soil into the plant, although some aquatic species (duckweed > elodea > parrot feather) can transform DDT into predominantly DDD with some DDE being formed. Of all the plants that can uptake DDE, Cucurbita pepo has been the most extensively studied, with translocation values approaching "hyperaccumulation" levels. Soil moisture, temperature, and plant density have all been documented as important factors in the uptake of DDE by Cucurbita pepo. Uptake may also be influenced positively by amendments such as biosurfactants, mycorrhizal inoculants, and low molecular weight organic acids (e.g., citric and oxalic acids). DDE microbial degradation by dehalogenases, dioxygenases, and hydrolases occurs under the proper conditions. Although several aerobic degradation pathways have been proposed, none has been fully verified. Very few aerobic pure cultures are capable of fully degrading DDE to CO2. Cometabolism of DDE by Pseudomonas sp., Alicaligens sp., and Terrabacter sp. grown on biphenyl has been reported; however, not all bacterial species that produce biphenyl dioxygenase degraded DDE. Arsenic and copper inhibit DDE degradation by aerobic microorganisms. Similarly, metal chelates such as EDTA inhibit the

  7. Double-layered ejecta craters on Mars: morphology, formation, and a comparison with the Ries ejecta blanket

    NASA Astrophysics Data System (ADS)

    Kenkmann, Thomas; Wulf, Gerwin; Sturm, Sebastian; Pietrek, Alexa

    2015-04-01

    The ejecta blankets of impact craters in volatile-rich environments often show characteristic layered ejecta morphologies. The so-called double-layer ejecta (DLE) craters are probably the most confusing crater types showing two ejecta layers with distinct morphologies. A phenomenological ejecta excavation and emplacement model for DLE craters is proposed based on a detailed case study of the Martian crater Steinheim - a textbook like, pristine DLE crater - and studies of other DLE craters [1]. The observations show that DLE craters on Mars are the result of an impact event into a rock/ice mixture that produces large amounts of shock-induced vaporization and melting of ground ice. The deposits of the ejecta curtain are wet in the distal part and dryer in composition in the proximal part. As a result, the outer ejecta layer is emplaced as medial and distal ejecta that propagate outwards in a fluid saturated debris flow mode after landing overrunning previously formed secondary craters. In contrast, the inner ejecta layer is formed by a translational slide of the proximal ejecta deposits. This slide overruns and superimposes parts of the outer ejecta layer. Basal melting of the ice components of the ejecta volumes at the transient crater rim is induced by frictional heating and the enhanced pressure at depth. The results indicate similar processes also for other planetary bodies with volatile-rich environments, such as Ganymede, Europa or the Earth. The Ries crater on Earth has a similar ejecta thickness distribution as DLE craters on Mars [2]. Here basal sliding and fluidization of the ejecta increases outward by the entrainment of locally derived Tertiary sands and clays, that are saturated with groundwater. References: [1] Wulf, G. & Kenkmann, T. (2015) Met. Planet. Sci. (in press); [2] Sturm, S., Wulf. G., Jung, D. & Kenkmann, T. (2013) Geology 41, 531-534.

  8. Nördlinger Ries campaign on Soil Emissions (NORISE) - DOAS measurements of NO2 and HCHO in an agricultural region

    NASA Astrophysics Data System (ADS)

    Zörner, Jan; Remmers, Julia; Dörner, Steffen; Eger, Philipp; Pöhler, Denis; Behrendt, Thomas; Meixner, Franz; Penning de Vries, Marloes; Wagner, Thomas

    2015-04-01

    Soil is a major source of total nitrogen oxide (NOx = NO + NO2) emissions with a fraction of about 15% on a global basis. Soil emissions, stemming from bacterial emissions of NO, are controlled by abiotic and microbiological processes which themselves depend on ambient environmental conditions like soil type, moisture content, temperature as well as agricultural management practices such as fertilization. In recent laboratory experiments it was found that dry soils also exhibit enhanced emissions of several volatile organic compounds (VOC) including HCHO when first wetted. A campaign dedicated to the analysis of trace gases emitted by soils was organized in the Nördlinger Ries in Bavaria, Germany, a 25 km wide circular plain, formed by a meteor impact about 14.5 million years ago and nowadays dominated by arable land. The main objective of the NORISE campaign is to characterize trace gas levels in a highly agricultural environment. The time frame, consequently, comprises a whole growing season from April 2014 to January 2015. The focus is on trace gases which can be measured using the DOAS approach in the UV/VIS spectral range, i.e. NO2 and HCHO, using two mini-MAX-DOAS instruments and one long-path DOAS instrument. The retrieved NO2 and HCHO column densities are examined for long-term variations over the entire growing season and short-term events which are both linked to environmental conditions like precipitation patterns and temperature changes. In addition, the analysis of soil samples taken from fields, distinguished between organic and conventional cultivation, gives further insights into soil activities.

  9. Degradation of light emitting diodes: a proposed methodology

    NASA Astrophysics Data System (ADS)

    Koh, Sau; Van Driel, Willem; Zhang, G. Q.

    2011-01-01

    Due to their long lifetime and high efficacy, light emitting diodes have the potential to revolutionize the illumination industry. However, self heat and high environmental temperature which will lead to increased junction temperature and degradation due to electrical overstress can shorten the life of the light emitting diode. In this research, a methodology to investigate the degradation of the LED emitter has been proposed. The epoxy lens of the emitter can be modelled using simplified Eyring methods whereas an equation has been proposed for describing the degradation of the LED emitters.

  10. Degradation in Solid Oxide Cells During High Temperature Electrolysis

    SciTech Connect

    Manohar Sohal

    2009-05-01

    Idaho National Laboratory has an ongoing project to generate hydrogen from steam using solid oxide electrolysis cells. One goal of that project is to address the technical and degradation issues associated with solid oxide electrolysis cells. This report covers a variety of these degradation issues, which were discussed during a workshop on “Degradation in Solid Oxide Electrolysis Cells and Strategies for its Mitigation,” held in Phoenix, AZ on October 27, 2008. Three major degradation issues related to solid oxide electrolysis cells discussed at the workshop are: • Delamination of O2-electrode and bond layer on steam/O2-electrode side • Contaminants (Ni, Cr, Si, etc.) on reaction sites (triple-phase boundary) • Loss of electrical/ionic conductivity of electrolyte. This list is not all inclusive, but the workshop summary can be useful in providing a direction for future research related to the degradation of solid oxide electrolysis cells.

  11. Drift Degradation Analysis

    SciTech Connect

    D. Kicker

    2004-09-16

    Degradation of underground openings as a function of time is a natural and expected occurrence for any subsurface excavation. Over time, changes occur to both the stress condition and the strength of the rock mass due to several interacting factors. Once the factors contributing to degradation are characterized, the effects of drift degradation can typically be mitigated through appropriate design and maintenance of the ground support system. However, for the emplacement drifts of the geologic repository at Yucca Mountain, it is necessary to characterize drift degradation over a 10,000-year period, which is well beyond the functional period of the ground support system. This document provides an analysis of the amount of drift degradation anticipated in repository emplacement drifts for discrete events and time increments extending throughout the 10,000-year regulatory period for postclosure performance. This revision of the drift degradation analysis was developed to support the license application and fulfill specific agreement items between the U.S. Nuclear Regulatory Commission (NRC) and the U.S. Department of Energy (DOE). The earlier versions of ''Drift Degradation Analysis'' (BSC 2001 [DIRS 156304]) relied primarily on the DRKBA numerical code, which provides for a probabilistic key-block assessment based on realistic fracture patterns determined from field mapping in the Exploratory Studies Facility (ESF) at Yucca Mountain. A key block is defined as a critical block in the surrounding rock mass of an excavation, which is removable and oriented in an unsafe manner such that it is likely to move into an opening unless support is provided. However, the use of the DRKBA code to determine potential rockfall data at the repository horizon during the postclosure period has several limitations: (1) The DRKBA code cannot explicitly apply dynamic loads due to seismic ground motion. (2) The DRKBA code cannot explicitly apply loads due to thermal stress. (3) The DRKBA

  12. Microbial degradation of herbicides.

    PubMed

    Singh, Baljinder; Singh, Kashmir

    2016-01-01

    Herbicides remain the most effective, efficient and economical way to control weeds; and its market continues to grow even with the plethora of generic products. With the development of herbicide-tolerant crops, use of herbicides is increasing around the world that has resulted in severe contamination of the environment. The strategies are now being developed to clean these substances in an economical and eco-friendly manner. In this review, an attempt has been made to pool all the available literature on the biodegradation of key herbicides, clodinafop propargyl, 2,4-dichlorophenoxyacetic acid, atrazine, metolachlor, diuron, glyphosate, imazapyr, pendimethalin and paraquat under the following objectives: (1) to highlight the general characteristic and mode of action, (2) to enlist toxicity in animals, (3) to pool microorganisms capable of degrading herbicides, (4) to discuss the assessment of herbicides degradation by efficient microbes, (5) to highlight biodegradation pathways, (6) to discuss the molecular basis of degradation, (7) to enlist the products of herbicides under degradation process, (8) to highlight the factors effecting biodegradation of herbicides and (9) to discuss the future aspects of herbicides degradation. This review may be useful in developing safer and economic microbiological methods for cleanup of soil and water contaminated with such compounds.

  13. Electrical connector

    DOEpatents

    Dilliner, Jennifer L.; Baker, Thomas M.; Akasam, Sivaprasad; Hoff, Brian D.

    2006-11-21

    An electrical connector includes a female component having one or more receptacles, a first test receptacle, and a second test receptacle. The electrical connector also includes a male component having one or more terminals configured to engage the one or more receptacles, a first test pin configured to engage the first test receptacle, and a second test pin configured to engage the second test receptacle. The first test receptacle is electrically connected to the second test receptacle, and at least one of the first test pin and the second test pin is shorter in length than the one or more terminals.

  14. Motor degradation prediction methods

    SciTech Connect

    Arnold, J.R.; Kelly, J.F.; Delzingaro, M.J.

    1996-12-01

    Motor Operated Valve (MOV) squirrel cage AC motor rotors are susceptible to degradation under certain conditions. Premature failure can result due to high humidity/temperature environments, high running load conditions, extended periods at locked rotor conditions (i.e. > 15 seconds) or exceeding the motor`s duty cycle by frequent starts or multiple valve stroking. Exposure to high heat and moisture due to packing leaks, pressure seal ring leakage or other causes can significantly accelerate the degradation. ComEd and Liberty Technologies have worked together to provide and validate a non-intrusive method using motor power diagnostics to evaluate MOV rotor condition and predict failure. These techniques have provided a quick, low radiation dose method to evaluate inaccessible motors, identify degradation and allow scheduled replacement of motors prior to catastrophic failures.

  15. Degraded document image enhancement

    NASA Astrophysics Data System (ADS)

    Agam, G.; Bal, G.; Frieder, G.; Frieder, O.

    2007-01-01

    Poor quality documents are obtained in various situations such as historical document collections, legal archives, security investigations, and documents found in clandestine locations. Such documents are often scanned for automated analysis, further processing, and archiving. Due to the nature of such documents, degraded document images are often hard to read, have low contrast, and are corrupted by various artifacts. We describe a novel approach for the enhancement of such documents based on probabilistic models which increases the contrast, and thus, readability of such documents under various degradations. The enhancement produced by the proposed approach can be viewed under different viewing conditions if desired. The proposed approach was evaluated qualitatively and compared to standard enhancement techniques on a subset of historical documents obtained from the Yad Vashem Holocaust museum. In addition, quantitative performance was evaluated based on synthetically generated data corrupted under various degradation models. Preliminary results demonstrate the effectiveness of the proposed approach.

  16. Electrical Conductivity.

    ERIC Educational Resources Information Center

    Hershey, David R.; Sand, Susan

    1993-01-01

    Explains how electrical conductivity (EC) can be used to measure ion concentration in solutions. Describes instrumentation for the measurement, temperature dependence and EC, and the EC of common substances. (PR)

  17. Electrical Conductivity.

    ERIC Educational Resources Information Center

    Allen, Philip B.

    1979-01-01

    Examines Drude's classical (1900) theory of electrical conduction, details the objections to and successes of the 1900 theory, and investigates the Quantum (1928) theory of conduction, reviewing its successes and limitations. (BT)

  18. Antifoam degradation testing

    SciTech Connect

    Lambert, D. P.; Zamecnik, J. R.; Newell, D. D.; Williams, M. S.

    2015-08-20

    This report describes the results of testing to quantify the degradation products resulting from the dilution and storage of Antifoam 747. Antifoam degradation is of concern to the Defense Waste Processing Facility (DWPF) due to flammable decomposition products in the vapor phase of the Chemical Process Cell vessels, as well as the collection of flammable and organic species in the offgas condensate. The discovery that hexamethyldisiloxane is formed from the antifoam decomposition was the basis for a Potential Inadequacy in the Safety Analysis declaration by the DWPF.

  19. Photovoltaic Degradation Risk: Preprint

    SciTech Connect

    Jordan, D. C.; Kurtz, S. R.

    2012-04-01

    The ability to accurately predict power delivery over the course of time is of vital importance to the growth of the photovoltaic (PV) industry. Important cost drivers include the efficiency with which sunlight is converted into power, how this relationship changes over time, and the uncertainty in this prediction. An accurate quantification of power decline over time, also known as degradation rate, is essential to all stakeholders - utility companies, integrators, investors, and researchers alike. In this paper we use a statistical approach based on historical data to quantify degradation rates, discern trends and quantify risks related to measurement uncertainties, number of measurements and methodologies.

  20. Electric generator

    DOEpatents

    Foster, Jr., John S.; Wilson, James R.; McDonald, Jr., Charles A.

    1983-01-01

    1. In an electrical energy generator, the combination comprising a first elongated annular electrical current conductor having at least one bare surface extending longitudinally and facing radially inwards therein, a second elongated annular electrical current conductor disposed coaxially within said first conductor and having an outer bare surface area extending longitudinally and facing said bare surface of said first conductor, the contiguous coaxial areas of said first and second conductors defining an inductive element, means for applying an electrical current to at least one of said conductors for generating a magnetic field encompassing said inductive element, and explosive charge means disposed concentrically with respect to said conductors including at least the area of said inductive element, said explosive charge means including means disposed to initiate an explosive wave front in said explosive advancing longitudinally along said inductive element, said wave front being effective to progressively deform at least one of said conductors to bring said bare surfaces thereof into electrically conductive contact to progressively reduce the inductance of the inductive element defined by said conductors and transferring explosive energy to said magnetic field effective to generate an electrical potential between undeformed portions of said conductors ahead of said explosive wave front.

  1. Black soils and/or sediments at the western border of the Nördlinger Ries (South Germany)

    NASA Astrophysics Data System (ADS)

    Mailänder, S.; Eberle, J.; Blümel, W. D.

    2009-04-01

    In the framework of a geoarchaeological research project by the Institute of Geography, University of Stuttgart, in the year 2006 the construction of a kerosene pipeline trench was monitored at the western border of the impact crater "Nördlinger Ries" in South Germany (MAILÄNDER ET AL. 2008). Thereby black horizons were recognized at several places. They occured predominantly in depressions and were covered by holocene colluvial sediments, but rested on different bedrocks which include mud- and sandstones as well as lime. The most of these horizons seemed to be rich in humic material and clay. By means of various studies, which involve sedimentological, pedological, archaeobotanical and -zoological analysis as well as 14C-(AMS)-datings, the periods and circumstances of the development of these black horizons are explored. The poster presents the itemised research methods and their first results. Particularly micromorphological analysis and mollusc classifications turned out to be very valuable to reconstruct the palaeoenvironmental conditions during their formation and subsequent modifications. First datings of bulk samples and charcoal pieces refer to the Atlantic period, but the measured ages distribute to a long time space from about cal BC 5200 to cal BC 4000. The outcomes of this investigation should facilitate a comparison with similar horizons which are recovered in several Central European sediment profiles, for example in the Amöneburger Becken near Marburg in Hessen (RITTWEGER 2000). Also their composition will be contrasted with samples from archaeological findings in the surrounding and the possibility of an anthropogenic influence on their development will be checked. References MAILÄNDER, S., W. D. BLÜMEL & J. EBERLE (2008): Paläoumweltbedingungen und anthropogene Landoberflächenveränderungen im Umfeld des frühkeltischen Fürstensitzes auf dem Ipf am Westrand des Nördlinger Rieses: Erste Geländebefunde und Auswertungen 2005/2006.- In

  2. Nördlinger Ries campaign on Soil Emissions (NORISE) - DOAS measurements of NO2 and HCHO in an agricultural region

    NASA Astrophysics Data System (ADS)

    Zörner, Jan; Remmers, Julia; Dörner, Steffen; Wang, Yang; Eger, Philipp; Pöhler, Dennis; Behrendt, Thomas; Meixner, Franz; Penning de Vries, Marloes; Wagner, Thomas

    2016-04-01

    Soil is a major source of total nitrogen oxide (NOx = NO + NO2) emissions with a fraction of about 15% on a global basis. Soil emissions, stemming from bacterial emissions of NO, are controlled by abiotic and microbiological processes which themselves depend on ambient environmental conditions like soil type, moisture content, temperature as well as agricultural management practices such as fertilization. In recent laboratory experiments it was found that dry soils also exhibit enhanced emissions of several volatile organic compounds (VOC) including HCHO when first wetted. At present, studies on soil emissions in humid climates are limited to point samples and laboratory measurements. Thus, a campaign was organized that is dedicated to the analysis of trace gases which are potentially emitted from soils over an entire area using ground based mini-MAX-DOAS measurements. Since soil emissions are assumed to be highest from lands predominantly used for agriculture, the Nördlinger Ries in Bavaria, Germany, a 25 km wide circular plain formed by a meteor impact about 14.5 million years ago, was chosen which nowadays is dominated by arable land. The main objective of the NORISE campaign was to characterize trace gas levels in a highly agricultural environment. The time frame, consequently, covered a whole growing season from April 2014 to January 2015. The focus was on trace gases which can be measured using the DOAS approach in the UV/VIS spectral range, i.e. NO2 and HCHO, using two mini-MAX-DOAS instruments and one long-path DOAS instrument. The retrieved NO2 and HCHO column densities were examined for long-term variations over the entire growing season and short-term events which are both linked to environmental conditions like precipitation patterns and temperature changes. In addition, the analysis of soil samples taken from fields, distinguished between organic and conventional cultivation, gives further insights into soil activities. In this work, we present

  3. Diagnosing Abiotic Degradation

    EPA Science Inventory

    The abiotic degradation of chlorinated solvents in ground water can be difficult to diagnose. Under current practice, most of the “evidence” is negative; specifically the apparent disappearance of chlorinated solvents with an accumulation of vinyl chloride, ethane, ethylene, or ...

  4. Degradative plasmids from sphingomonads.

    PubMed

    Stolz, Andreas

    2014-01-01

    Large plasmids ('megaplasmids') are commonly found in members of the Alphaproteobacterial family Sphingomonadaceae ('sphingomonads'). These plasmids contribute to the extraordinary catabolic flexibility of this group of organisms, which degrade a broad range of recalcitrant xenobiotic compounds. The genomes of several sphingomonads have been sequenced during the last years. In the course of these studies, also the sequences of several plasmids have been determined. The analysis of the published information and the sequences deposited in the public databases allowed a first classification of these plasmids into a restricted number of groups according to the proteins involved in the initiation of replication, plasmid partition and conjugation. The sequence comparisons demonstrated that the plasmids from sphingomonads encode for four main groups of replication initiation (Rep) proteins. These Rep proteins belong to the protein superfamilies RepA_C (Pfam 04796), Rep_3 (Pfam 01051), RPA (Pfam 10134) and HTH-36 (Pfam 13730). The 'degradative megaplasmids' pNL2, pCAR3, pSWIT02, pCHQ1, pISP0, and pISP1, which code for genes involved in the degradation of aromatic hydrocarbons, carbazole, dibenzo-p-dioxin and γ-hexachlorocyclohexane, carry Rep proteins which either belong to the RepA_C- (plasmids pNL2, pCAR3, pSWIT02), Rep-3- (plasmids pCHQ1, pISP0) or RPA-superfamily (pISP1). The classification of these 'degradative megaplasmids' into three groups is also supported by sequence comparisons of the proteins involved in plasmid partition (ParAB) and the organization of the three genes on the respective plasmids. All analysed 'degradative megaplasmids' carry genes, which might allow a conjugative transfer of the plasmids. Sequence comparisons of these genes suggest the presence of at least two types of transfer functions, which either are closer related to the tra- or vir-genes previously described for plasmids from other sources.

  5. Detection of pump degradation

    SciTech Connect

    Greene, R.H.; Casada, D.A.; Ayers, C.W.

    1995-08-01

    This Phase II Nuclear Plant Aging Research study examines the methods of detecting pump degradation that are currently employed in domestic and overseas nuclear facilities. This report evaluates the criteria mandated by required pump testing at U.S. nuclear power plants and compares them to those features characteristic of state-of-the-art diagnostic programs and practices currently implemented by other major industries. Since the working condition of the pump driver is crucial to pump operability, a brief review of new applications of motor diagnostics is provided that highlights recent developments in this technology. The routine collection and analysis of spectral data is superior to all other technologies in its ability to accurately detect numerous types and causes of pump degradation. Existing ASME Code testing criteria do not require the evaluation of pump vibration spectra but instead overall vibration amplitude. The mechanical information discernible from vibration amplitude analysis is limited, and several cases of pump failure were not detected in their early stages by vibration monitoring. Since spectral analysis can provide a wealth of pertinent information concerning the mechanical condition of rotating machinery, its incorporation into ASME testing criteria could merit a relaxation in the monthly-to-quarterly testing schedules that seek to verify and assure pump operability. Pump drivers are not included in the current battery of testing. Operational problems thought to be caused by pump degradation were found to be the result of motor degradation. Recent advances in nonintrusive monitoring techniques have made motor diagnostics a viable technology for assessing motor operability. Motor current/power analysis can detect rotor bar degradation and ascertain ranges of hydraulically unstable operation for a particular pump and motor set. The concept of using motor current or power fluctuations as an indicator of pump hydraulic load stability is presented.

  6. Organic chemical degradation by remote study of the redox conditions

    NASA Astrophysics Data System (ADS)

    Fernandez, P. M.; Revil, A.; Binley, A. M.; Bloem, E.; French, H. K.

    2014-12-01

    Monitoring the natural (and enhanced) degradation of organic contaminants is essential for managing groundwater quality in many parts of the world. Contaminated sites often have limited access, hence non-intrusive methods for studying redox processes, which drive the degradation of organic compounds, are required. One example is the degradation of de-icing chemicals (glycols and organic salts) released to the soil near airport runways during winter. This issue has been broadly studied at Oslo airport, Gardermoen, Norway using intrusive and non-intrusive methods. Here, we report on laboratory experiments that aim to study the potential of using a self-potential, DCresistivity, and time-domain induced polarization for geochemical characterization of the degradation of Propylene Glycol (PG). PG is completely miscible in water, does not adsorb to soil particles and does not contribute to the electrical conductivity of the soil water. When the contaminant is in the unsaturated zone near the water table, the oxygen is quickly consumed and the gas exchange with the surface is insufficient to ensure aerobic degradation, which is faster than anaerobic degradation. Since biodegradation of PG is highly oxygen demanding, anaerobic pockets can exist causing iron and manganese reduction. It is hypothesised that nitrate would boost the degradation rate under such conditions. In our experiment, we study PG degradation in a sand tank. We provide the system with an electron highway to bridge zones with different redox potential. This geo-battery system is characterized by self-potential, resistivity and induced polarization anomalies. An example of preliminary results with self-potential at two different times of the experiment can be seen in the illustration. These will be supplemented with more direct information on the redox chemistry: in-situ water sampling, pH, redox potential and electrical conductivity measurements. In parallel, a series of batch experiments have been

  7. Degradation of veteran Si modules in hot-humid locations in México

    NASA Astrophysics Data System (ADS)

    Martinez-Escobar, D.; Sánchez-Pérez, P. A.; Santos-Magdaleno, R.; Ortega-Cruz, J.; Sánchez-Juárez, A.

    2016-09-01

    In this work, the results of the research carried out on degradation mechanisms of c-SI PV modules after > 10 years of exposure in a Hot and humid climate in Mexico are presented. Degradation analysis using visual inspection, electrical performance, EL image, and IR was performed. 1-measurement analysis was implemented to determine the degradation rate per year. The Pmax degradation rate obtained was 1:41%/yr. The results presented indicate that most of the electrical degradation is due FF drop (increased series resistance) among other details. The aim of this work is to provide information regarding the long term reliability and degradation rate of c-Si modules in the hot and humid climate in Mexico.

  8. Electrically powered hand tool

    DOEpatents

    Myers, Kurt S.; Reed, Teddy R.

    2007-01-16

    An electrically powered hand tool is described and which includes a three phase electrical motor having a plurality of poles; an electrical motor drive electrically coupled with the three phase electrical motor; and a source of electrical power which is converted to greater than about 208 volts three-phase and which is electrically coupled with the electrical motor drive.

  9. Characterization of voltage degradation in dynamic field gradient focusing

    PubMed Central

    Burke, Jeffrey M.; Ivory, Cornelius F.

    2010-01-01

    Dynamic field gradient focusing (DFGF) is an equilibrium gradient method that utilizes an electric field gradient to simultaneously separate and concentrate charged analytes based on their individual electrophoretic mobilities. This work describes the use of a 2-D nonlinear, numerical simulation to examine the impact of voltage loss from the electrodes to the separation channel, termed voltage degradation, and distortions in the electric field on the performance of DFGF. One of the design parameters that has a large impact on the degree of voltage degradation is the placement of the electrodes in relation to the separation channel. The simulation shows that a distance of about 3 mm from the electrodes to the separation channel gives the electric field profile with least amount of voltage degradation. The simulation was also used to describe the elution of focused protein peaks. The simulation shows that elution under constant electric field gradient gives better performance than elution through shallowing of the electric field. Qualitative agreement between the numerical simulation and experimental results is shown. The simulation also illustrates that the presence of a defocusing region at the cathodic end of the separation channel causes peak dispersion during elution. The numerical model is then used to design a system that does not suffer from a defocusing region. Peaks eluted under this design experienced no band broadening in our simulations. Preliminary experimental results using the redesigned chamber are shown. PMID:18306183

  10. TALSPEAK Solvent Degradation

    SciTech Connect

    Leigh R. Martin; Bruce J. Mincher

    2009-09-01

    Understanding the radiolytic degradation behavior of organic molecules involved in new or existing schemes for the recycle of used nuclear fuels is of significant interest for sustaining a closed nuclear fuel cycle. Here we have conducted several lines of investigation to begin understanding the effects of radiolysis on the aqueous phase of the TALSPEAK process for the separation of the trivalent lanthanides from the trivalent actinides. Using the 60-Co irradiator at the INL, we have begun to quantify the effects of radiation on the aqueous phase complexants used in this separation technique, and how this will affect the actinide lanthanide separation factor. In addition we have started to develop methodologies for stable product identification, a key element in determining the degradation pathways. We have also introduced a methodology to investigate the effects of alpha radiolysis that has previously received limited attention.

  11. Degradation of Spacecraft Materials

    NASA Technical Reports Server (NTRS)

    Dever, Joyce; Banks, Bruce; deGroh, Kim; Miller, Sharon

    2004-01-01

    This chapter includes descriptions of specific space environmental threats to exterior spacecraft materials. The scope will be confined to effects on exterior spacecraft surfaces, and will not, therefore, address environmental effects on interior spacecraft systems, such as electronics. Space exposure studies and laboratory simulations of individual and combined space environemntal threats will be summarized. A significant emphasis is placed on effects of Earth orbit environments, because the majority of space missions have been flown in Earth orbits which have provided a significant amount of data on materials effects. Issues associated with interpreting materials degradation results will be discussed, and deficiencies of ground testing will be identified. Recommendations are provided on reducing or preventing space environmental degradation through appropriate materials selection.

  12. Nylon separators. [thermal degradation

    NASA Technical Reports Server (NTRS)

    Lim, H. S.

    1977-01-01

    A nylon separator was placed in a flooded condition in K0H solution and heated at various high temperatures ranging from 60 C to 110 C. The weight decrease was measured and the molecular weight and decomposition product were analyzed to determine: (1) the effect of K0H concentration on the hydrolysis rate; (2) the effect of K0H concentration on nylon degradation; (3) the activation energy at different K0H concentrations; and (4) the effect of oxygen on nylon degradation. The nylon hydrolysis rate is shown to increase as K0H concentration is decreased 34%, giving a maximum rate at about 16%. Separator hydrolysis is confirmed by molecular weight decrease in age of the batteries, and the reaction of nylon with molecular oxygen is probably negligible, compared to hydrolysis. The extrapolated rate value from the high temperature experiment correlates well with experimental values at 35 degrees.

  13. Ion flux and energy virtual sensor for measuring ion flux and energy distribution at a RF biased electrode in ICP reactor (RIE-mode)

    NASA Astrophysics Data System (ADS)

    Bogdanova, M. A.; Lopaev, D. V.; Zyryanov, S. M.

    2016-10-01

    The modern technology of micro- and nanoelectronics involves a great number of steps, such as pattern transfer, where Reactive Ion Etching (RIE) in rf plasma reactors is widely used. To control the etching process, the ion flux and ion energy distribution should be managed precisely. However, the measurements of these parameters during the process in the real-time operation are impossible. This paper is devoted to the construction of a virtual diagnostics of the Ion Energy Distribution (IED) function. This method for the determination of the ion energy spectrum on the surface of rf biased electrode is based on model calculations using in-situ measured discharge parameters. The results of IED virtual diagnostics were compared with data, obtained by Retarded Field Energy Analyzer (RFEA). This was done for Ar- and H2-plasmas operated under low-pressure rf plasma conditions. The good agreement between the model and the experimental justifies the conclusion that the IED virtual diagnostics can be applied successfully. This enables the in-situ monitoring of the IED at the electrode surface in RIE reactors.

  14. Ion Flux and Energy Virtual Sensor for Measuring Ion Flux and Energy Distribution at a RF Biased Electrode in ICP Reactor (RIE-MODE)

    NASA Astrophysics Data System (ADS)

    Bogdanova, Maria; Lopaev, Dmitriy; Zyryanov, Sergey

    2014-10-01

    The modern technology of micro- and nanoelectronics involves a great number of steps, e.g. pattern transfer, where Reactive Ion Etching (RIE) in rf plasma reactors is widely used. RIE is carried out placing samples on the surface of rf biased electrode, as rule in an asymmetric rf low-pressure discharge. In an effort to control the etching process, ion flux and energy distribution should be controlled precisely as much as possible. However, measurements of them during the process in the real-time operation mode are impossible. Nevertheless, if virtual sensor of ion flux and energy can be developed, such a sensor would allow monitoring ion energy spectrum without direct measurements during plasma processing. This virtual plasma diagnostics should include calculation of ion energy spectrum based on the simple physical model of ion motion in collisionless rf sheath. In addition the modeling has to be fulfilled in the real-time operation mode by using the set of external measurable parameters. This paper is just devoted to creation of such ion energy distribution virtual diagnostics. The reported study was supported by RFBR, research Project No. 14-02-31599.

  15. Polymer Coatings Degradation Properties

    DTIC Science & Technology

    1985-02-01

    release; distribution unlimited. 17. DISTRIBUTION STATEMENT (of 1*. 460060 00md ( Ag 8106k 2.It 4011--t - RepiI) Is. SUPPLEMENTARY NOTES IS. KEY WORDS...two radicals interact The photodegradation mechanism of poly(urethanes) is not known in detail, however, much has been added to our understanding. The...red PAS is also consistent with the probable degradation mechanism, i.e. disappearance of the urethane link- ages . This is another sensitive technique

  16. WEATHERABILITY OF ENHANCED DEGRADABLE PLASTICS

    EPA Science Inventory

    The main objective of this study was to assess the performance and the asociated variability of several selected enhanced degradable plastic materials under a variety of different exposure conditions. Other objectives were to identify the major products formed during degradation ...

  17. An overview of degradable polymers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many degradable polymers are being investigated for research purpose or for possible commercial use. This overview provides a listing of the more important degradable polymers and their mechanisms of action. Some application areas, particularly in packaging, housewares, personal care, biomaterials, ...

  18. An overview of degradable polymers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many degradable polymers are being investigated for research purpose or for possible commercial use. This overview provides a listing of the more important degradable polymers and their mechanisms of action. Some application areas, particularly in packaging, housewares, personal care, biomaterials...

  19. Electrical Injuries

    MedlinePlus

    ... your injuries are depends on how strong the electric current was, what type of current it was, how it moved through your body, and how long you were exposed. Other factors include how ... you should see a doctor. You may have internal damage and not realize it.

  20. Detection of pump degradation

    SciTech Connect

    Casada, D.

    1994-12-31

    There are a variety of stressors that can affect the operation of centrifugal pumps. Although these general stressors are active in essentially all centrifugal pumps, the stressor level and the extent of wear and degradation can vary greatly. Parameters that affect the extent of stressor activity are manifold. In order to assure the long-term operational readiness of a pump, it is important to both understand the nature and magnitude of the specific degradation mechanisms and to monitor the performance of the pump. The most commonly applied method of monitoring the condition of not only pumps, but rotating machinery in general, is vibration analysis. Periodic or continuous spectral vibration analysis is a cornerstone of most pump monitoring programs. In the nuclear industry, non-spectral vibration monitoring of safety-related pumps is performed in accordance with the ASME code. Although vibration analysis has dominated the condition monitoring field for many years, there are other measures that have been historically used to help understand pump condition: advances in historically applied technologies and developing technologies offer improved monitoring capabilities. The capabilities of several technologies (including vibration analysis, dynamic pressure analysis, and motor power analysis) to detect the presence and magnitude of both stressors and resultant degradation are discussed.

  1. Microbial degradation of hydrazine

    SciTech Connect

    Ou, L.T.

    1987-07-01

    Hydrazine is toxic to many forms of bacteria. The activities of the autotrophic nitrifiers Nitrosomonas and Nitrobacter, denitrifying bacteria, and anaerobic methanogens were inhibited by the chemical. In addition, hydrazine prolonged the lag phase of growth as well as inhibited growth of the soil bacterium Enterobacter cloacae. Due to rapid disappearance in soil, hydrazine at 100 ..mu..g/g exhibited only temporary inhibition on soil bacterial populations. However, hydrazine at 500 ..mu..g/g caused a significant reduction of soil bacterial populations, although fungal populations in soil were enhanced by the presence of hydrazine. Despite its toxicity to soil bacteria, hydrazine in small quantities was cometabolically degraded to nitrogen gas by Nitrosomonas. An enzyme system of nitrogen-fixing heterotrophic bacteria was able to convert hydrazine to ammonia. However, it was not clear that the bacteria could utilize hydrazine as a sole source of nitrogen for growth. In the present study, the authors describe the isolation of an Achromobacter sp. from soil that had a high capacity to degrade hydrazine. Attempts to establish degradation pathways are also reported.

  2. Detection of pump degradation

    SciTech Connect

    Casada, D.

    1995-04-01

    There are a variety of stressors that can affect the operation of centrifugal pumps. Although these general stressors are active in essentially all centrifugal pumps, the stressor level and the extent of wear and degradation can vary greatly. Parameters that affect the extent of stressor activity are manifold. In order to assure the long-term operational readiness of a pump, it is important to both understand the nature and magnitude of the specific degradation mechanisms and to monitor the performance of the pump. The most commonly applied method of monitoring the condition of not only pumps, but rotating machinery in general, is vibration analysis. Periodic or continuous special vibration analysis is a cornerstone of most pump monitoring programs. In the nuclear industry, non-spectral vibration monitoring of safety-related pumps is performed in accordance with the ASME code. Pump head and flow rate are also monitored, per code requirements. Although vibration analysis has dominated the condition monitoring field for many years, there are other measures that have been historically used to help understand pump condition; advances in historically applied technologies and developing technologies offer improved monitoring capabilities. The capabilities of several technologies (including vibration analysis, dynamic pressure analysis, and motor power analysis) to detect the presence and magnitude of both stressors and resultant degradation are discussed.

  3. Biogeochemical Cycles in Degraded Lands

    NASA Technical Reports Server (NTRS)

    Davidson, Eric A.; Vieira, Ima Celia G.; ReisdeCarvalho, Claudio Jose; DeanedeAbreuSa, Tatiana; deSouzaMoutinho, Paulo R.; Figueiredo, Ricardo O.; Stone, Thomas A.

    2004-01-01

    The objectives of this project were to define and describe the types of landscapes that fall under the broad category of "degraded lands" and to study biogeochemical cycles across this range of degradation found in secondary forests. We define degraded land as that which has lost part of its capacity of renovation of a productive ecosystem, either in the context of agroecosystems or as native communities of vegetation. This definition of degradation permits evaluation of biogeochemical constraints to future land uses.

  4. Biogeochemical Cycles in Degraded Lands

    NASA Technical Reports Server (NTRS)

    Davidson, Eric A.; Vieira, Ima Celia G.; ReisdeCarvalho, Claudio Jose; DeaneDeAbreuSa, Tatiana; deSpozaMoutinho, Paulo R.; Figueiredo, Ricardo O.; Stone, Thomas A.

    2003-01-01

    The objectives of this project were to define and describe the types of landscapes that fall under the broad category of "degraded lands" and to study biogeochemical cycles across this range of degradation found in secondary forests. We define degraded land as that which has lost part of its capacity of renovation of a productive ecosystem, either in the context of agroecosystems or as native communities of vegetation. This definition of degradation permits evaluation of biogeochemical constraints to future land uses.

  5. Life-Cycle-Cost Evaluation on Degradation Diagnosis for Cables

    NASA Astrophysics Data System (ADS)

    Shimakage, Toyonari; Wu, Kai; Kato, Takeyoshi; Okamoto, Tatsuki; Suzuoki, Yasuo

    Degradation diagnosis is aimed at preventing unexpected failure and extending the service life of electric power apparatuses. It is, however, necessary to investigate the economic feasibility of degradation diagnosis, because the life-cycle cost of cable maintenance changes with the diagnostic parameters such as diagnosis cost, diagnosis interval and replacement criterion. In this paper, based on the actual data of water-tree degradation, we proposed a method of life-cycle-cost evaluation and evaluated the economic effect of degradation diagnosis. We also discussed the economic feasibility of practical nondestructive diagnosis of 6.6 kV XLPE cable, i. e. DC leakage current measurement and residual charge measurement, and compared the economic effects of these methods. As a result, the residual charge measurement is economically feasible and has higher effectiveness than the DC leakage current measurement.

  6. Microbial Degradation of Asphalt1

    PubMed Central

    Phillips, U. A.; Traxler, R. W.

    1963-01-01

    Organisms of the genera Pseudomonas, Chromobacterium, and Bacillus capable of degrading asphalt were isolated by enrichment cultures. The asphalt degradation by these organisms varied from 3 to 25% after incubation for 1 week. The effects of temperature, pH, and atmosphere of incubation on asphalt degradation were investigated and were shown to vary with different organisms on the same substrate. PMID:16349633

  7. Electricity unplugged

    NASA Astrophysics Data System (ADS)

    Karalis, Aristeidis

    2009-02-01

    The judge was driving back late one cold winter night. Entering the garage, the battery-charging indicator in his wirelessly powered electric car came on. "Home at last," crossed his mind. He swiped his personal smartcard on the front-door detector to be let in. He heard a "charging" beep from his mobile phone. The blinking cursor on the half-finished e-mail on the laptop had been waiting all day on the side table. He picked the computer up and walked towards his desk. "Good evening, your honour. Your wirelessly heated robe," said the butler-robot as it approached from the kitchen. Putting on the electric garment, he sat on the medical desk chair. His artificial heart was now beating faster.

  8. Electric power

    SciTech Connect

    Chase, M.

    1988-01-01

    This text examines the critical problems faced by the electric power industry, shown in the context of a detailed description of the history and development of the industry. A new industry initiative is proposed that will allow for a more effective response to industry fluctuations. Topics covered include developments in power technology federal nuclear power regulation and legislation, environmentalism and conservationism, industry financial problems, capital minimization, and responses to utility responsibility.

  9. Electric Car

    NASA Technical Reports Server (NTRS)

    1977-01-01

    NASA's Lewis Research Center undertook research toward a practical, economical battery with higher energy density. Borrowing from space satellite battery technology, Lewis came up with a nickel-zinc battery that promises longer life and twice the range of the lead-acid counterpart. Lewis researchers fabricated a prototype battery and installed it in an Otis P-500 electric utility van, using only the battery space already available and allowing battery weight equal to that of the va's conventional lead-acid battery

  10. Degradability of Polymers for Implantable Biomedical Devices

    PubMed Central

    Lyu, SuPing; Untereker, Darrel

    2009-01-01

    Many key components of implantable medical devices are made from polymeric materials. The functions of these materials include structural support, electrical insulation, protection of other materials from the environment of the body, and biocompatibility, as well as other things such as delivery of a therapeutic drug. In such roles, the stability and integrity of the polymer, over what can be a very long period of time, is very important. For most of these functions, stability over time is desired, but in other cases, the opposite–the degradation and disappearance of the polymer over time is required. In either case, it is important to understand both the chemistry that can lead to the degradation of polymers as well as the kinetics that controls these reactions. Hydrolysis and oxidation are the two classes of reactions that lead to the breaking down of polymers. Both are discussed in detail in the context of the environmental factors that impact the utility of various polymers for medical device applications. Understanding the chemistry and kinetics allows prediction of stability as well as explanations for observations such as porosity and the unexpected behavior of polymeric composite materials in some situations. In the last part, physical degradation such interfacial delamination in composites is discussed. PMID:19865531

  11. Outdoor PV Degradation Comparison

    SciTech Connect

    Jordan, D. C.; Smith, R. M.; Osterwald, C. R.; Gelak, E.; Kurtz, S. R.

    2011-02-01

    As photovoltaic (PV) penetration of the power grid increases, it becomes vital to know how decreased power output; may affect cost over time. In order to predict power delivery, the decline or degradation rates must be determined; accurately. At the Performance and Energy Rating Testbed (PERT) at the Outdoor Test Facility (OTF) at the; National Renewable Energy Laboratory (NREL) more than 40 modules from more than 10 different manufacturers; were compared for their long-term outdoor stability. Because it can accommodate a large variety of modules in a; limited footprint the PERT system is ideally suited to compare modules side-by-side under the same conditions.

  12. Photothermal degradation studies

    NASA Technical Reports Server (NTRS)

    Liang, R. H.

    1985-01-01

    Key reaction intermediates of photooxidation identified and characterized by laser flash Electron Spin Resonance (ESR) spectroscopy were discussed. Effects of temperature and ultraviolet intensity were studied in order to develop meaningful accelerated testing procedures for encapsulant evaluation. In a program to study the failure of Tedlar/ethylene vinyl acetate (EVA)/stainless steel modules, failure modes similar to those observed outdoors in real-time conditions were simulated in accelerated testing. An experimental technique was developed to quantitatively assess the extent of degradation.

  13. Thermal oxidative degradation of ethylene tetrafluoroethylene copolymer systems

    NASA Astrophysics Data System (ADS)

    Elders, Jonathan Patrick

    Thermo-oxidative degradation of ethylene tetrafluoroethylene (ETFE) was investigated to determine how modifications for use in an electrical wire system affected its thermal stability. Modifications included electron irradiation and subsequent cross-linking during manufacture and contact with a metal surface. Samples with irradiation histories between 0 and 48 MRads were investigated. Degradation of ETFE was enhanced by contact with a metal "conductor" surface: silver - coated copper. Polymer degradation was analyzed by weight loss kinetics (thermogravimetric analysis (TGA)), changes in polymer morphology (differential scanning calorimetry (DSC)), optical microscopy, attenuated total reflectance (ATR) infrared spectroscopy, and gas chromatography - mass spectroscopy (GC/MS). Conductor aging (copper permeation through silver with subsequent oxidation) was investigated using scanning Auger Electron Spectroscopy (AES). Conductor aging is enhanced in the presence of the polymer surface. Interactions between conductor and polymer were analyzed by optical microscopy, scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). The rate of polymer degradation from 220°C to 280°C was independent of time and extent of degradation, and rate was proportional to irradiation dose. The activation energy for degradation of unirradiated ETFE was 227 kJ/mol and decreased from 150 to 138 kJ/mol for ETFE irradiated to doses between 6 and 48 MRads. Rates of degradation at 300°C to 320°C were dependent on the extent of degradation. Rates of degradation at temperatures between 230°C and 310°C were an order of magnitude larger in the presence of a conductor than in its absence, and activation energies for degradation in the presence of conductor were reduced to 120 kJ/mol. Degradation was modeled as the combination of bulk polymer degradation and catalytic degradation at the polymer-metal interface. ETFE aged at 250°C in the presence or absence of a conductor

  14. Lignin-degrading enzymes.

    PubMed

    Pollegioni, Loredano; Tonin, Fabio; Rosini, Elena

    2015-04-01

    A main goal of green biotechnology is to reduce our dependence on fossil reserves and to increase the use of renewable materials. For this, lignocellulose, which is composed of cellulose, hemicellulose and lignin, represents the most promising feedstock. The latter is a complex aromatic heteropolymer formed by radical polymerization of guaiacyl, syringyl, and p-hydroxyphenyl units linked by β-aryl ether linkages, biphenyl bonds and heterocyclic linkages. Accordingly, lignin appears to be a potentially valuable renewable aromatic chemical, thus representing a main pillar in future biorefinery. The resistance of lignin to breakdown is the main bottleneck in this process, although a variety of white-rot fungi, as well as bacteria, have been reported to degrade lignin by employing different enzymes and catabolic pathways. Here, recent investigations have expanded the range of natural biocatalysts involved in lignin degradation/modification and significant progress related to enzyme engineering and recombinant expression has been made. The present review is focused primarily on recent trends in ligninolytic green biotechnology to suggest the potential (industrial) application of ligninolytic enzymes. Future perspectives could include synergy between natural enzymes from different sources (as well as those obtained by protein engineering) and other pretreatment methods that may be required for optimal results in enzyme-based, environmentally friendly, technologies.

  15. Microbial naphthenic Acid degradation.

    PubMed

    Whitby, Corinne

    2010-01-01

    Naphthenic acids (NAs) are an important group of trace organic pollutants predominantly comprising saturated aliphatic and alicyclic carboxylic acids. NAs are ubiquitous; occurring naturally in hydrocarbon deposits (petroleum, oil sands, bitumen, and crude oils) and also have widespread industrial uses. Consequently, NAs can enter the environment from both natural and anthropogenic processes. NAs are highly toxic, recalcitrant compounds that persist in the environment for many years, and it is important to develop efficient bioremediation strategies to decrease both their abundance and toxicity in the environment. However, the diversity of microbial communities involved in NA-degradation, and the mechanisms by which NAs are biodegraded, are poorly understood. This lack of knowledge is mainly due to the difficulties in identifying and purifying individual carboxylic acid compounds from complex NA mixtures found in the environment, for microbial biodegradation studies. This paper will present an overview of NAs, their origin and fate in the environment, and their toxicity to the biota. The review describes the microbial degradation of both naturally occurring and chemically synthesized NAs. Proposed pathways for aerobic NA biodegradation, factors affecting NA biodegradation rates, and possible bioremediation strategies are also discussed.

  16. Induction of PAH degradation in a phenanthrene-degrading pseudomonad

    SciTech Connect

    Stringfellow, W.T.; Chen, S.H.; Aitken, M.D.

    1995-12-31

    Recent evidence suggests that different polycyclic aromatic hydrocarbon (PAH) substrates are metabolized by common enzymes in PAH-degrading bacteria, implying that inducers for low-molecular-weight PAH degradation may coinduce for the metabolism of higher-molecular-weight compounds. The authors have tested this hypothesis with a well-characterized PAH-degrading bacterium, Pseudomonas saccharophila P-15. Growth of P-15 on salicylate, a metabolite of phenanthrene degradation, and a known inducer for naphthalene degradation, induced the metabolism of both substrates. Several potential inducers were then tested for their effects on metabolism of the four-ring compounds pyrene and fluoranthene, neither of which is a growth substrate for P-15, but both of which can be metabolized by this organism. Incubation of P-15 in the presence of phenanthrene or salicylate induced the metabolism of pyrene and fluoranthene in resting-cell assays. Catechol, another intermediate of naphthalene and phenanthrene degradation, did not induce the metabolism of either compound and interfered with the inducing effect of salicylate. These results have implications for strategies designed to maintain PAH degradation in contaminated environments, particularly for compounds that are degraded slowly or are degraded only by nongrowth metabolism.

  17. Climate Action Benefits: Electricity

    EPA Pesticide Factsheets

    This page provides background on the relationship between electricity and climate change and describes what the CIRA Electricity analyses cover. It provides links to the subsectors Electricity Demand and Electricity Supply.

  18. Electrical receptacle

    DOEpatents

    Leong, R.

    1993-06-22

    The invention is a receptacle for a three prong electrical plug which has either a tubular or U-shaped grounding prong. The inventive receptacle has a grounding prong socket which is sufficiently spacious to prevent the socket from significantly stretching when a larger, U-shaped grounding prong is inserted into the socket, and having two ridges to allow a snug fit when a smaller tubular shape grounding prong is inserted into the socket. The two ridges are made to prevent the socket from expanding when either the U-shaped grounding prong or the tubular grounding prong is inserted.

  19. Electrical receptacle

    DOEpatents

    Leong, Robert

    1993-01-01

    The invention is a receptacle for a three prong electrical plug which has either a tubular or U-shaped grounding prong. The inventive receptacle has a grounding prong socket which is sufficiently spacious to prevent the socket from significantly stretching when a larger, U-shaped grounding prong is inserted into the socket, and having two ridges to allow a snug fit when a smaller tubular shape grounding prong is inserted into the socket. The two ridges are made to prevent the socket from expanding when either the U-shaped grounding prong or the tubular grounding prong is inserted.

  20. Solar Electricity

    NASA Technical Reports Server (NTRS)

    1988-01-01

    ARCO Solar manufactures PV Systems tailored to a broad variety of applications. PV arrays are routinely used at remote communications installations to operate large microwave repeaters, TV and radio repeaters rural telephone, and small telemetry systems that monitor environmental conditions. Also used to power agricultural water pumping systems, to provide electricity for isolated villages and medical clinics, for corrosion protection for pipelines and bridges, to power railroad signals, air/sea navigational aids, and for many types of military systems. ARCO is now moving into large scale generation for utilities.

  1. Effects of HSQ e-beam Resist Processing on the Fabrication of ICP-RIE Etched TiO2 Nanostructures

    NASA Astrophysics Data System (ADS)

    Hotovy, Ivan; Kostic, Ivan; Predanocy, Martin; Nemec, Pavol; Rehacek, Vlastimil

    2016-12-01

    Patterning of metal oxide nanostructures with different shapes and well-defined size may play an important role in the improvement of MEMS systems, sensors and optical devices. We investigated the effects of HSQ e-beam resist processing on the fabrication of sputtered TiO2 nanostructures. They were patterned using direct write e-beam lithography combined with ICP-RIE etching in CF4/Ar plasma. Experimental results confirmed that the HSQ resist with a thickness of about 600 nm is suitable as a masking material for optimal etching process and allows patterning of the dots array in TiO2 sputtered films with a thickness up 150 nm. TiO2 arrays with a minimal dots diameter of 180 nm and spacing of 1000 nm were successfully developed.

  2. Fabrication of fluorinated polyimide microgrids using magnetically controlled reactive ion etching (MC-RIE) and their applications to an ion drag integrated micropump

    NASA Astrophysics Data System (ADS)

    Furuya, Akinori; Shimokawa, Fusao; Matsuura, Tohru; Sawada, Renshi

    1996-09-01

    Magnetically controlled reactive ion etching (MC-RIE) of a fluorinated polyimide substrate achieved etching selectivity of up to 2600, resulting in a smoothly etched surface and structures hundreds of micrometers high having good perpendicularity. This technique is useful for three-dimensional microfabrication. As an example of a typical application, we fabricated an ion drag integrated micropump with microgrid sets consisting of 0960-1317/6/3/003/img1 high pole-shaped counter-electrode elements arranged like a pair of interleaved combs by using a fluorinated polyimide as the structural material, metallization, and lift-off using a ZnO sacrificial layer. This micropump moved ethanol with a flow rate of about 0960-1317/6/3/003/img2 when 200 V was applied to the counter electrodes.

  3. Études des propriétés électro-optiques d'une série de diphtalocyanines de terres rares

    NASA Astrophysics Data System (ADS)

    Videlot, C.; Fichou, D.; Garnier, F.

    1998-06-01

    In this work, we describe the study of photovoltaic cells for a series of rare earth diphthalocyanines. This p type organic compounds have been used in Schottky and pn configurations. Current-voltage curves and action spectra show different replies in energy's conversion according to the rare earth of the diphthalocyanine. Dans ce travail, nous décrivons l'étude de cellules photovoltaïques pour une série de diphtalocyanines de terres rares. Ces composés organiques de type p ont été étudiés dans des configurations Schottky et hétérojonction pn. Les courbes de courant-tension et les spectres d'action montrent des réponses différentes dans la conversion de l'énergie suivant la terre rare de la diphtalocyanine.

  4. Double emittance exchanger as a bunch compressor for the MaRIE XFEL electron beam line at 1 GeV

    NASA Astrophysics Data System (ADS)

    Malyzhenkov, Alexander; Carlsten, Bruce E.; Yampolsky, Nikolai A.

    2017-03-01

    We demonstrate an alternative realization of a bunch compressor (specifically, the second bunch compressor for the MaRIE XFEL beamline, 1GeV electron energy) using a double emittance exchanger (EEX) and a telescope in the transverse phase space. We compare our results with a traditional bunch compressor realized via a chicane, taking into account the nonlinear dynamics, Coherent Synchrotron Radiation (CSR) and Space Charge (SC) effects. In particular, we use the Elegant code for tracking particles through the beamline, and analyze the evolution of the eigen-emittances to separate the influence of the CSR/SC effects from the nonlinear dynamics effects. We optimize the scheme parameters to reach a desirable compression factor and minimize the emittance growth. We observe dominant CSR effects in our scheme, resulting in critical emittance growth, and introduce an alternative version of an emittance exchanger with a reduced number of bending magnets to minimize the impact of CSR effects.

  5. Double Emittance Exchanger as a Bunch Compressor for the MaRIE XFEL electron beam line at 1GeV

    SciTech Connect

    Malyzhenkov, Alexander; Yampolsky, Nikolai; Carlsten, Bruce Eric

    2016-09-22

    We demonstrate an alternative realization of a bunch compressor (specifically the second bunch compressor for the MaRIE XFEL beamline, 1GeV electron energy) using a double emittance exchanger (EEX) and a telescope in the transverse phase space.We compare our results with a traditional bunch compressor realized via chicane, taking into account the nonlinear dynamics, Coherent Synchrotron Radiation (CSR) and Space Charge (SC) effects. In particular, we use the Elegant code for tracking particles through the beam line and analyze the eigen-emittances evolution to separate the influence of the CSR/SC effects from the nonlinear dynamics effects. We optimize the scheme parameters to reach a desirable compression factor and minimize the emittance growth. We observe dominant CSR-effects in our scheme resulting in critical emittance growth and introduce alternative version of an emittance exchanger with a reduced number of bending magnets to minimize the impact of CSR effects.

  6. Application de l’analyse des séries chronologiques à la projection d’effectifs de population scolaire par la méthode des composantes

    PubMed Central

    Smith, Herbert L.

    2016-01-01

    Cet article veut montrer qu’on peut réécrire des modèles démographiques en vue de réaliser des projections par cohorte, en les transposant dans un modèle économétrique vecteur autoré-gressif (VAR). De cette façon, la méthode des composantes se dote d’un cadre stochastique qui étend son envergure. Le potentiel de cette perspective est illustré à travers l’exemple d’une projection d’effectifs de population scolaire. Il met en valeur une série d’équations qui permet de vérifier la validité de plusieurs choix de modélisations habituellement utilisées dans le domaine de la prévision. PMID:27346921

  7. Cause and Effects of Fluorocarbon Degradation in Electronics and Opto-Electronic Systems

    NASA Technical Reports Server (NTRS)

    Predmore, Roamer E.; Canham, John S.

    2002-01-01

    Trace degradation of fluorocarbon or halocarbon materials must be addressed in their application in sensitive systems. As the dimensions and/or tolerances of components in a system decrease, the sensitivity of the system to trace fluorocarbon or halocarbon degradation products increases. Trace quantities of highly reactive degradation products from fluorocarbons have caused a number of failures of flight hardware. It is of utmost importance that the risk of system failure, resulting from trace amounts of reactive fluorocarbon degradation products be addressed in designs containing fluorocarbon or halocarbon materials. Thermal, electrical, and mechanical energy input into the system can multiply the risk of failure.

  8. Oil degradation in soil.

    PubMed

    Raymond, R L; Hudson, J O; Jamison, V W

    1976-04-01

    The environmental effects of adding certain selected petroleum products to field soils at widely separated geographical locations under optimum conditions for biodegradation were studied. The locations selected for study of soil biodegradation of six oils (used crankcase oil from cars, used crankcase oil from trucks, an Arabian Heavy crude oil, a Coastal Mix crude oil, a home heating oil no. 2, and a residual fuel oil no. 6) were Marcus Hook, Pennsylvania, Tulsa, Oklahoma, and Corpus Christi, Texas. The investigative process, covering a period of 1 year at each location, was conducted in 14 fields plots (1.7 by 3.0 m) to which the oils were added in a single application at a rate of 11.9 m3/4 X 10(3) m2. One-half of the plots at each location were fertilized, and the incorporation of the oils and fertilizers was accomplished with rototillers to a depth of 10 to 15 cm. Concentrations of all oils decreased significantly at all locations. The average reduction ranged from 48.5 to 90.0% depending upon the type of oil and location. Rates of degradation did not exceed 2.4 m3/4 X 10(3) m2 per month. Compositional changes in the oil with time were investigated using silica gel fractionation, gas chromatography, and ultraviolet absorbance. With the possible exception of the two fuel oils, the compositional changes were generally in the same direction for all of the oils. The silica gel fractionation and gravimetric data on residual oils show that all classes of compounds were degraded, but the more polar type degrade more slowly. Analysis of runoff water, leachate, and soils indicated that at the concentration applied no oil less was observed from these plots via water movement. No significant movement of lead compounds added to the soils in the used crankcase oils was observed. Significant increases in hydrocarbon-utilizing microorganisms were demonstrated in all treated plots using either the pure hydrocarbon, n-hexadecane, or the applied oils as the growth substrate

  9. Accelerated degradation of silicon metallization systems

    NASA Technical Reports Server (NTRS)

    Lathrop, J. W.

    1983-01-01

    Clemson University has been engaged for the past five years in a program to determine the reliability attributes of solar cells by means of accelerated test procedures. The cells are electrically measured and visually inspected and then subjected for a period of time to stress in excess of that normally encountered in use, and then they are reinspected. Changes are noted and the process repeated. This testing has thus far involved 23 different unencapsulated cell types from 12 different manufacturers, and 10 different encapsulated cell types from 9 different manufacturers. Reliability attributes of metallization systems can be classified as major or minor, depending on the severity of the effects observed. As a result of the accelerated testing conducted under the Clemson program, major effects have been observed related to contact resistance and to mechanical adherence and solderability. This paper does not attempt a generalized survey of accelerated test results, but rather concentrates on one particular attribute of metallization that has been observed to cause electrical degradation - increased contact resistance due to Schottky barrier formation. In this example basic semiconductor theory was able to provide an understanding of the electrical effects observed during accelerated stress testing.

  10. Thermal battery degradation mechanisms

    SciTech Connect

    Missert, Nancy A.; Brunke, Lyle Brent

    2015-09-01

    Diffuse reflectance IR spectroscopy (DRIFTS) was used to investigate the effect of accelerated aging on LiSi based anodes in simulated MC3816 batteries. DRIFTS spectra showed that the oxygen, carbonate, hydroxide and sulfur content of the anodes changes with aging times and temperatures, but not in a monotonic fashion that could be correlated to phase evolution. Bands associated with sulfur species were only observed in anodes taken from batteries aged in wet environments, providing further evidence for a reaction pathway facilitated by H2S transport from the cathode, through the separator, to the anode. Loss of battery capacity with accelerated aging in wet environments was correlated to loss of FeS2 in the catholyte pellets, suggesting that the major contribution to battery performance degradation results from loss of active cathode material.

  11. Radiation degradation of cellulose

    NASA Astrophysics Data System (ADS)

    Leonhardt, J.; Arnold, G.; Baer, M.; Langguth, H.; Gey, M.; Hübert, S.

    The application of straw and other cellulose polymers as feedstuff for ruminants is limited by its low digestibility. During recent decades it was attempted to increase the digestibility of straw by several chemical and physical methods. In this work some results of the degradation of gamma and electron treated wheat straw are reported. Complex methods of treatment (e.g. radiation influence and influence of lyes) are taken into consideration. In vitro-experiments with radiation treated straw show that the digestibility can be increased from 20 % up to about 80 %. A high pressure liquid chromatography method was used to analyze the hydrolysates. The contents of certain species of carbohydrates in the hydrolysates in dependence on the applied dose are given.

  12. Basic Electricity. Part 2.

    ERIC Educational Resources Information Center

    Kilmer, Donald C.

    This guide, the second (part 2) in a set of four guides, is designed for the student interested in a vocation in electrical work, and includes two units: Unit IV--Electrical Theory, covering thirteen lessons (matter, the atom, electrical charges in the atom, rules of electric charges, electricity, atoms in an electrical conductor, electrical…

  13. Realizing the geothermal electricity potential—water use and consequences

    NASA Astrophysics Data System (ADS)

    Shankar Mishra, Gouri; Glassley, William E.; Yeh, Sonia

    2011-07-01

    Electricity from geothermal resources has the potential to supply a significant portion of US baseload electricity. We estimate the water requirements of geothermal electricity and the impact of potential scaling up of such electricity on water demand in various western states with rich geothermal resources but stressed water resources. Freshwater, degraded water, and geothermal fluid requirements are estimated explicitly. In general, geothermal electricity has higher water intensity (l kWh - 1) than thermoelectric or solar thermal electricity. Water intensity decreases with increase in resource enthalpy, and freshwater gets substituted by degraded water at higher resource temperatures. Electricity from enhanced geothermal systems (EGS) could displace 8-100% of thermoelectricity generated in most western states. Such displacement would increase stress on water resources if re-circulating evaporative cooling, the dominant cooling system in the thermoelectric sector, is adopted. Adoption of dry cooling, which accounts for 78% of geothermal capacity today, will limit changes in state-wide freshwater abstraction, but increase degraded water requirements. We suggest a research and development focus to develop advanced energy conversion and cooling technologies that reduce water use without imposing energy and consequent financial penalties. Policies should incentivize the development of higher enthalpy resources, and support identification of non-traditional degraded water sources and optimized siting of geothermal plants.

  14. MALDI analysis of estane degradation

    SciTech Connect

    Haining, J; Kober, E M; LeMay, J D; Mays, J; Nonidez, W; Overturf III, G E; Russell, B

    1999-03-26

    SEUMALDI has been successfully used to accurately measure the MW of hydrolysis degradation products from Estane 5703. Reasonable structure assignments have been made to the degradation products and several observations reported. Most of the low MW degradation peaks have been identified as ester hydrolysis fragments. The data suggest that the polyester macrodiol may be shorter than the {approximately}2000 amu reported by the manufacturer. Experiments are ongoing to determine if hydrolysis occurs within the material's applied environment.

  15. Degraded Crater Rim

    NASA Technical Reports Server (NTRS)

    2002-01-01

    (Released 3 May 2002) The Science The eastern rim of this unnamed crater in Southern Arabia Terra is very degraded (beaten up). This indicates that this crater is very ancient and has been subjected to erosion and subsequent bombardment from other impactors such as asteroids and comets. One of these later (younger) craters is seen in the upper right of this image superimposed upon the older crater rim material. Note that this smaller younger crater rim is sharper and more intact than the older crater rim. This region is also mantled with a blanket of dust. This dust mantle causes the underlying topography to take on a more subdued appearance. The Story When you think of Arabia, you probably think of hot deserts and a lot of profitable oil reserves. On Mars, however, Southern Arabia Terra is a cold place of cratered terrain. This almost frothy-looking image is the badly battered edge of an ancient crater, which has suffered both erosion and bombardment from asteroids, comets, or other impacting bodies over the long course of its existence. A blanket of dust has also settled over the region, which gives the otherwise rugged landscape a soft and more subdued appearance. The small, round crater (upper left) seems almost gemlike in its setting against the larger crater ring. But this companionship is no easy romance. Whatever formed the small crater clearly whammed into the larger crater rim at some point, obliterating part of its edge. You can tell the small crater was formed after the first and more devastating impact, because it is laid over the other larger crater. How much younger is the small one? Well, its rim is also much sharper and more intact, which gives a sense that it is probably far more youthful than the very degraded, ancient crater.

  16. Transcellular degradation of axonal mitochondria

    PubMed Central

    Davis, Chung-ha O.; Kim, Keun-Young; Bushong, Eric A.; Mills, Elizabeth A.; Boassa, Daniela; Shih, Tiffany; Kinebuchi, Mira; Phan, Sebastien; Zhou, Yi; Bihlmeyer, Nathan A.; Nguyen, Judy V.; Jin, Yunju; Ellisman, Mark H.; Marsh-Armstrong, Nicholas

    2014-01-01

    It is generally accepted that healthy cells degrade their own mitochondria. Here, we report that retinal ganglion cell axons of WT mice shed mitochondria at the optic nerve head (ONH), and that these mitochondria are internalized and degraded by adjacent astrocytes. EM demonstrates that mitochondria are shed through formation of large protrusions that originate from otherwise healthy axons. A virally introduced tandem fluorophore protein reporter of acidified mitochondria reveals that acidified axonal mitochondria originating from the retinal ganglion cell are associated with lysosomes within columns of astrocytes in the ONH. According to this reporter, a greater proportion of retinal ganglion cell mitochondria are degraded at the ONH than in the ganglion cell soma. Consistently, analyses of degrading DNA reveal extensive mtDNA degradation within the optic nerve astrocytes, some of which comes from retinal ganglion cell axons. Together, these results demonstrate that surprisingly large proportions of retinal ganglion cell axonal mitochondria are normally degraded by the astrocytes of the ONH. This transcellular degradation of mitochondria, or transmitophagy, likely occurs elsewhere in the CNS, because structurally similar accumulations of degrading mitochondria are also found along neurites in superficial layers of the cerebral cortex. Thus, the general assumption that neurons or other cells necessarily degrade their own mitochondria should be reconsidered. PMID:24979790

  17. Process for electrically interconnecting electrodes

    DOEpatents

    Carey, Paul G.; Thompson, Jesse B.; Colella, Nicolas J.; Williams, Kenneth A.

    2002-01-01

    Electrical interconnects for solar cells or other electronic components using a silver-silicone paste or a lead-tin (Pb--Sn) no-clean fluxless solder cream, whereby the high breakage of thin (<6 mil thick) solar cells using conventional solder interconnect is eliminated. The interconnects of this invention employs copper strips which are secured to the solar cells by a silver-silicone conductive paste which can be used at room temperature, or by a Pb--Sn solder cream which eliminates undesired residue on the active surfaces of the solar cells. Electrical testing using the interconnects of this invention has shown that no degradation of the interconnects developed under high current testing, while providing a very low contact resistance value.

  18. Technology and Climate Trends in PV Module Degradation: Preprint

    SciTech Connect

    Jordan, D. C.; Wohlgemuth, J. H.; Kurtz, S. R.

    2012-10-01

    To sustain the commercial success of photovoltaic (PV) technology it is vital to know how power output decreases with time. Unfortunately, it can take years to accurately measure the long-term degradation of new products, but past experience on older products can provide a basis for prediction of degradation rates of new products. An extensive search resulted in more than 2000 reported degradation rates with more than 1100 reported rates that include some or all IV parameters. In this paper we discuss how the details of the degradation data give clues about the degradation mechanisms and how they depend on technology and climate zones as well as how they affect current and voltage differently. The largest contributor to maximum power decline for crystalline Si technologies is short circuit current (or maximum current) degradation and to a lesser degree loss in fill factor. Thin-film technologies are characterized by a much higher contribution from fill factor particularly for humid climates. Crystalline Si technologies in hot & humid climates also display a higher probability to show a mixture of losses (not just short circuit current losses) compared to other climates. The distribution for the module I-V parameters (electrical mismatch) was found to change with field exposure. The distributions not only widened but also developed a tail at the lower end, skewing the distribution.

  19. Technology and Climate Trends in PV Module Degradation (Presentation)

    SciTech Connect

    Jordan, D.; Wohlgemuth, J.; Kurtz, S.

    2012-10-01

    To sustain the commercial success of photovoltaic (PV) technology it is vital to know how power output decreases with time. Unfortunately, it can take years to accurately measure the long-term degradation of new products, but past experience on older products can provide a basis for prediction of degradation rates of new products. An extensive search resulted in more than 2000 reported degradation rates with more than 1100 reported rates that include some or all IV parameters. In this presentation we discuss how the details of the degradation data give clues about the degradation mechanisms and how they depend on technology and climate zones as well as how they affect current and voltage differently. The largest contributor to maximum power decline for crystalline Si technologies is short circuit current (or maximum current) degradation and to a lesser degree loss in fill factor. Thin-film technologies are characterized by a much higher contribution from fill factor particularly for humid climates. Crystalline Si technologies in hot & humid climates also display a higher probability to show a mixture of losses (not just short circuit current losses) compared to other climates. The distribution for the module I-V parameters (electrical mismatch) was found to change with field exposure. The distributions not only widened but also developed a tail at the lower end, skewing the distribution.

  20. Research of Isolation and Degradation Conditions of Petroleum Degrading Marine

    NASA Astrophysics Data System (ADS)

    Fangrui, Guo

    2017-01-01

    A novel petroleum-degrading microbial strain was isolated from sediment samples in estuary of Bohai Sea estuary beaches. The strain was primarily identified as Alcanivorax sp. and named Alcanivorax sp. H34. Effect of PH values, temperature, nitrogen and phosphorus concentrations on degradation of H34 were investigated. The paraffinic components average degradation rate of H34 ungrowth cells under optimized conditions was studied. The results showed that the optimal growth conditions of H34 are were temperature of 30°C, initial PH of 7.0, nitrogen concentration of 3g/L, phosphorus concentration of 3g/L, and paraffinic components average degradation rates of H34 ungrowth cells was 41.6%, while total degradation rate was 45.5%.

  1. Cellular senescence and protein degradation

    PubMed Central

    Deschênes-Simard, Xavier; Lessard, Frédéric; Gaumont-Leclerc, Marie-France; Bardeesy, Nabeel; Ferbeyre, Gerardo

    2014-01-01

    Autophagy and the ubiquitin–proteasome pathway (UPP) are the major protein degradation systems in eukaryotic cells. Whereas the former mediate a bulk nonspecific degradation, the UPP allows a rapid degradation of specific proteins. Both systems have been shown to play a role in tumorigenesis, and the interest in developing therapeutic agents inhibiting protein degradation is steadily growing. However, emerging data point to a critical role for autophagy in cellular senescence, an established tumor suppressor mechanism. Recently, a selective protein degradation process mediated by the UPP was also shown to contribute to the senescence phenotype. This process is tightly regulated by E3 ubiquitin ligases, deubiquitinases, and several post-translational modifications of target proteins. Illustrating the complexity of UPP, more than 600 human genes have been shown to encode E3 ubiquitin ligases, a number which exceeds that of the protein kinases. Nevertheless, our knowledge of proteasome-dependent protein degradation as a regulated process in cellular contexts such as cancer and senescence remains very limited. Here we discuss the implications of protein degradation in senescence and attempt to relate this function to the protein degradation pattern observed in cancer cells. PMID:24866342

  2. Membrane Degradation Accelerated Stress Test

    SciTech Connect

    Mukundan, Rangachary; Borup, Rodney L.

    2015-01-21

    These are a set of slides that deal with membrane degradation accelerated stress test. Specifically, the following topics are covered: membrane degradation FCTT drive cycle; membrane ASTs; current membrane ASTs damage mechanisms; proposed membrane AST, RH cycling in H2/Air; current proposed AST; 2min/2min AST damage mechanism; 30sec/45sec RH cycling at OCV.

  3. Compositional Effects on Electromechanical Degradation of RAINBOW Actuators

    NASA Technical Reports Server (NTRS)

    Dausch, David E.; Wise, Stephanie A.

    1998-01-01

    The effect of ceramic composition on the electromechanical displacement degradation of RAINBOW (Reduced and Internally Biased Oxide Wafer) actuators was investigated. RAINBOWs were fabricated from commercially available PZT-5H and PZT-5A piezoelectric disks as well as from tape cast PLZT piezoelectric 7/65/35 and electrostrictive 9/65/35 compositions. Displacement properties were measured at low electric fields (10 to 13 kV/cm) under loads of 0 to 500 g, and displacement degradation as a function of time was observed over 107 cycles. The PZT-5A and PLZT 9/65/35 compositions exhibited minimal decrease in displacement when load was applied. Furthermore, these compositions retained approximately 65 percent of their initial displacement after 10(exp 7) cycles under a load of 300 g. PZT-5H and PLZT 7/65/35 degraded completely under these conditions.

  4. Degradation of cyanotoxins (microcystin) in drinking water using photoelectrooxidation.

    PubMed

    Garcia, A C A; Rodrigues, M A S; Xavier, J L N; Gazulla, V; Meneguzzi, A; Bernardes, A M

    2015-05-01

    The discharge of sewage and industrial effluents containing high concentrations of pollutants in water bodies increases eutrophication. Cyanobacteria, some of the organisms whose growth is promoted by high nutrient concentrations, are resistant and produce several types of toxins, known as cyanotoxins, highly harmful to human beings. Current water treatment systems for the public water supply are not efficient in degradation of toxins. Advanced oxidation processes (AOP) have been tested for the removal of cyanotoxins, and the results have been positive. This study examines the application of photoelectrooxidation in the degradation of cyanotoxins (microcystins). The performance of the oxidative processes involved was evaluated separately: Photocatalysis, Electrolysis and Photoelectrooxidation. Results showed that the electrical current and UV radiation were directly associated with toxin degradation. The PEO system is efficient in removing cyanotoxins, and the reduction rate reached 99%. The final concentration of toxin was less than 1 µg/L of microcystin in the treated solution.

  5. Degradation by acetic acid for crystalline Si photovoltaic modules

    NASA Astrophysics Data System (ADS)

    Masuda, Atsushi; Uchiyama, Naomi; Hara, Yukiko

    2015-04-01

    The degradation of crystalline Si photovoltaic modules during damp-heat test was studied using some test modules with and without polymer film insertion by observing electrical and electroluminescence properties and by chemical analyses. Acetic acid generated by the hydrolysis decomposition of ethylene vinyl acetate used as an encapsulant is the main origin of degradation. The change in electroluminescence images is explained on the basis of the corrosion of electrodes by acetic acid. On the other hand, little change was observed at the pn junction even after damp-heat test for a long time. Therefore, carrier generation occurs even after degradation; however, such generated carriers cannot be collected owing to corrosion of electrodes. The guiding principle that module structure and module materials without saving acetic acid into the modules was obtained.

  6. Refractory Degradation by Slag Attack in Coal Gasification

    DTIC Science & Technology

    2009-02-01

    chemicals and electric power. Feedstock materials such as coal , petroleum coke (petcoke), natural gas, or biomass contain numerous minerals and a...reacted with distinct microstructures are presented in Figure 5 and Figure 6. Coal slag on a grain agglomerate of both refractories remained on a...REFRACTORY DEGRADATION BY SLAG ATTACK IN COAL GASIFICATION Jinichiro Nakano 1,2 , Sridhar Seetharaman 1,2 , James Bennett 3 , Kyei-Sing

  7. Remote inhibition of polymer degradation.

    SciTech Connect

    Clough, Roger Lee; Celina, Mathias Christopher

    2005-08-01

    Polymer degradation has been explored on the basis of synergistic infectious and inhibitive interaction between separate materials. A dual stage chemiluminescence detection system with individually controlled hot stages was applied to probe for interaction effects during polymer degradation in an oxidizing environment. Experimental confirmation was obtained that volatile antioxidants can be transferred over a relatively large distance. The thermal degradation of a polypropylene (PP) sample receiving traces of inhibitive antioxidants from a remote source is delayed. Similarly, volatiles from two stabilized elastomers were also capable of retarding a degradation process remotely. This observation demonstrates inhibitive cross-talk as a novel interactive phenomenon between different polymers and is consequential for understanding general polymer interactions, fundamental degradation processes and long-term aging effects of multiple materials in a single environment.

  8. Bacterial degradation of aminopyrine.

    PubMed

    Blecher, H; Blecher, R; Wegst, W; Eberspaecher, J; Lingens, F

    1981-11-01

    1. Four strains of bacteria growing with aminopyrine as sole source of carbon were isolated from soil and were identified as strains of Phenylobacterium immobilis. 2. Strain M13 and strain E, the type species of Phenylobacterium immobilis (DSM 1986), which had been isolated by enrichment with chloridazon (5-amino-4-chloro-2-phenyl-2H-pyridazin-3-one) were used to investigate the bacterial degradation of aminopyrine. 3. Three metabolites were isolated and identified as: 4-(dimethylamino)-1,2-dihydro-1,5-dimethyl-2-(2,3-dihydro-2,3-dihydroxy-4,6-cyc lohexadien-1-yl)-3H-pyrazol-3-one, 4-(dimethylamino)-1,2-dihydro-1,5-dimethyl-2-(2,3-dihydroxyphenyl)-3H-pyrazol-3 -one and 4-(dimethylamino)-1,2-dihydro-1,5-dimethyl-3H-pyrazol-3-one. 4. An enzyme extract from cells of strain m13 was shown to further metabolize the catechol derivative of aminopyrine, with the formation of 2-pyrone-6-carboxylic acid. 5. Results indicate that the benzene ring of aminopyrine is the principal site of microbial metabolism.

  9. Enzymatic degradation of endomorphins.

    PubMed

    Janecka, Anna; Staniszewska, Renata; Gach, Katarzyna; Fichna, Jakub

    2008-11-01

    Centrally acting plant opiates, such as morphine, are the most frequently used analgesics for the relief of severe pain, even though their undesired side effects are serious limitation to their usefulness. The search for new therapeutics that could replace morphine has been mainly focused on the development of peptide analogs or peptidomimetics with high selectivity for one receptor type and high bioavailability, that is good blood-brain barrier permeability and enzymatic stability. Drugs, in order to be effective, must be able to reach the target tissue and to remain metabolically stable to produce the desired effects. The study of naturally occurring peptides provides a rational and powerful approach in the design of peptide therapeutics. Endogenous opioid peptides, endomorphin-1 and endomorphin-2, are two potent and highly selective mu-opioid receptor agonists, discovered only a decade ago, which display potent analgesic activity. However, extensive studies on the possible use of endomorphins as analgesics instead of morphine met with failure due to their instability. This review deals with the recent investigations that allowed determine degradation pathways of endomorphins in vitro and in vivo and propose modifications that will lead to more stable analogs.

  10. International ultraviolet explorer solar array power degradation

    NASA Technical Reports Server (NTRS)

    Day, J. H., Jr.

    1983-01-01

    The characteristic electrical performance of each International Ultraviolet Explorer (IUE) solar array panel is evaluated as a function of several prevailing variables (namely, solar illumination, array temperature and solar cell radiation damage). Based on degradation in the current-voltage characteristics of the array due to solar cell damage accumulated over time by space charged particle radiations, the available IUE solar array power is determined for life goals up to 10 years. Best and worst case calculations are normalized to actual IUE flight data (available solar array power versus observatory position) to accurately predict the future IUE solar array output. It is shown that the IUE solar array can continue to produce more power than is required at most observatory positions for at least 5 more years.

  11. Atmospheric electricity

    NASA Technical Reports Server (NTRS)

    1987-01-01

    In the last three years the focus was on the information contained in the lightning measurement, which is independent of other meteorological measurements that can be made from space. The characteristics of lightning activity in mesoscale convective systems were quantified. A strong relationship was found between lightning activity and surface rainfall. It is shown that lightning provides a precursor signature for wet microbursts (the strong downdrafts that produce windshears hazardous to aircraft) and that the lightning signature is a direct consequence of storm evolution. The Universities Space Research Association (USRA) collaborated with NASA scientists in the preliminary analysis and scientific justification for the design and deployment of an optical instrument which can detect lightning from geostationary orbit. Science proposals for the NASA mesoscale science program and for the Tethered Satellite System were reviewed. The weather forecasting research and unmanned space vehicles. Software was written to ingest and analyze the lightning ground strike data on the MSFC McIDAS system. The capabilities which were developed have a wide application to a number of problems associated with the operational impacts of electrical discharge within the atmosphere.

  12. Degradation evaluation of microelectromechanical thermal actuators

    NASA Astrophysics Data System (ADS)

    Luo, J. K.; Fu, Y. Q.; Huang, Q. A.; Williams, J. A.; Milne, W. I.

    2008-02-01

    Metal based thermal microactuators normally have lower operation temperatures than those of Si-based ones; hence they have great potential for applications. However, metal-based thermal actuators easily suffer from degradation such as plastic deformation. In this study, planar thermal actuators were made by a single mask process using electroplated nickel as the active material, and their thermal degradation has been studied. Electrical tests show that the Ni-based thermal actuators deliver a maximum displacement of ~20 m at an average temperature of ~420 °C, much lower than that of Si-based microactuators. However, the displacement strongly depends on the frequency and peak voltage of the pulse applied. Back bending was clearly observed at a maximum temperature as low as 240 °C. Both forward and backward displacements increase with increasing the temperature up to ~450 °C, and then decreases with power. Scanning electron microscopy observation clearly showed that Ni structure deforms and reflows at power above 50mW. The compressive stress is believed to be responsible for Ni piling-up (creep), while the tensile stress upon removing the pulse current is responsible for necking at the hottest section of the device. Energy dispersive X-ray diffraction analysis revealed severe oxidation of the Ni-structure induced by Joule-heating of the current.

  13. Can Single Crystal (U-Th)/He Zircon Ages from Nördlinger Ries Suevite be Linked to Impact-Related Shock Effects?

    NASA Astrophysics Data System (ADS)

    van Soest, M. C.; Cooper, F. J.; Wartho, J.; Hodges, K.; Buchner, E.; Schmieder, M.; Koeberl, C.

    2010-12-01

    Dating of impact-related material is difficult especially when pristine impact melt is unavailable. In the absence of such melts, most geochronometers in shocked basement or melt-poor impact rocks yield only partially reset or non-reset ages. In such cases, application of the low closure temperature apatite and zircon (U-Th)/He geochronometers can be successful, since impact-related physical and thermal shock should reset the He systematics in both minerals in most materials affected by the impact. For a proof of concept study on the well-studied Ries impact structure, we (U-Th)/He dated apatites (14.08 ± 0.26 Ma 2σ, n = 5) and zircons (14.26 ± 0.31 Ma 2σ, n = 10) from two Aumühle quarry suevite samples and one Polsingen quarry impact melt rock, which was dated at 14.37 ± 0.30 Ma (2σ) using Ar-Ar stepwise heating of recrystallized K-feldspar melt (Buchner et al., 2010). The (U-Th)/He ages agree well with the 14.37 Ma age, but are slightly younger than the suggested age of 14.59 ± 0.20 Ma (2σ - based on recent, post 1995, Ar-Ar data, Buchner et al., 2010) for the impact structure. However, among the 27 zircons dated, 6 were partially reset (>16Ma), and 11 zircons yielded younger dates (<13.5 Ma).The younger dates are problematic for successful (U-Th)/He dating of impact structures of unknown age, as they would be identified incorrectly as the age of the impact event. The cause for these younger dates may be: a) partial He loss due to a post-impact thermal event, which at Ries is unlikely as there is no geological evidence for such an event; b) compromised He retention due to metamictization by progressive radiation damage; or c) compromised He retention due to impact shock-related effects. The latter two causes can produce similar visual effects on zircon and the He loss mechanism is also similar, i.e. changes in the zircon crystal structure on a micro scale. However, the effects of these processes on zircon have been documented extensively by non

  14. Mesoporous Nano-Silica Serves as the Degradation Inhibitor in Polymer Dielectrics

    PubMed Central

    Yang, Yang; Hu, Jun; He, Jinliang

    2016-01-01

    A new generation of nano-additives for robust high performance nanodielectrics is proposed. It is demonstrated for the first time that mesoporous material could act as “degradation inhibitor” for polymer dielectrics to sequestrate the electrical degradation products then restrain the electrical aging process especially under high temperature conditions, which is superior to the existing additives of nanodielectrics except further increasing the dielectric strength. Polyethylenimine (PEI) loaded nano-scaled mesoporous silica MCM-41 (nano-MS) is doped into the dielectric matrix to prepare the PP/MCM-41-PEI nanocomposites. PEI provides the amines to capture the electrical degradation products while the MCM-41 brackets afford large adsorption surface, bring down the activating temperature of the absorbent then enhance the absorptive capacity. The electrical aging tests confirm the contribution of the mesoporous structure to electrical aging resistance and FT-IR analysis of the electrical degraded regions demonstrates the chemical absorption especially under high temperature conditions. Take the experimental data as examples, extending the aging durability and dielectric strength of polymer dielectrics by 5 times and 16%, respectively, can have substantial commercial significance in energy storage, power electronics and power transmission areas. PMID:27338622

  15. Mesoporous Nano-Silica Serves as the Degradation Inhibitor in Polymer Dielectrics.

    PubMed

    Yang, Yang; Hu, Jun; He, Jinliang

    2016-06-24

    A new generation of nano-additives for robust high performance nanodielectrics is proposed. It is demonstrated for the first time that mesoporous material could act as "degradation inhibitor" for polymer dielectrics to sequestrate the electrical degradation products then restrain the electrical aging process especially under high temperature conditions, which is superior to the existing additives of nanodielectrics except further increasing the dielectric strength. Polyethylenimine (PEI) loaded nano-scaled mesoporous silica MCM-41 (nano-MS) is doped into the dielectric matrix to prepare the PP/MCM-41-PEI nanocomposites. PEI provides the amines to capture the electrical degradation products while the MCM-41 brackets afford large adsorption surface, bring down the activating temperature of the absorbent then enhance the absorptive capacity. The electrical aging tests confirm the contribution of the mesoporous structure to electrical aging resistance and FT-IR analysis of the electrical degraded regions demonstrates the chemical absorption especially under high temperature conditions. Take the experimental data as examples, extending the aging durability and dielectric strength of polymer dielectrics by 5 times and 16%, respectively, can have substantial commercial significance in energy storage, power electronics and power transmission areas.

  16. Mesoporous Nano-Silica Serves as the Degradation Inhibitor in Polymer Dielectrics

    NASA Astrophysics Data System (ADS)

    Yang, Yang; Hu, Jun; He, Jinliang

    2016-06-01

    A new generation of nano-additives for robust high performance nanodielectrics is proposed. It is demonstrated for the first time that mesoporous material could act as “degradation inhibitor” for polymer dielectrics to sequestrate the electrical degradation products then restrain the electrical aging process especially under high temperature conditions, which is superior to the existing additives of nanodielectrics except further increasing the dielectric strength. Polyethylenimine (PEI) loaded nano-scaled mesoporous silica MCM-41 (nano-MS) is doped into the dielectric matrix to prepare the PP/MCM-41-PEI nanocomposites. PEI provides the amines to capture the electrical degradation products while the MCM-41 brackets afford large adsorption surface, bring down the activating temperature of the absorbent then enhance the absorptive capacity. The electrical aging tests confirm the contribution of the mesoporous structure to electrical aging resistance and FT-IR analysis of the electrical degraded regions demonstrates the chemical absorption especially under high temperature conditions. Take the experimental data as examples, extending the aging durability and dielectric strength of polymer dielectrics by 5 times and 16%, respectively, can have substantial commercial significance in energy storage, power electronics and power transmission areas.

  17. Anaerobic benzene degradation by bacteria

    PubMed Central

    Vogt, Carsten; Kleinsteuber, Sabine; Richnow, Hans‐Hermann

    2011-01-01

    Summary Benzene is a widespread and toxic contaminant. The fate of benzene in contaminated aquifers seems to be primarily controlled by the abundance of oxygen: benzene is aerobically degraded at high rates by ubiquitous microorganisms, and the oxygen‐dependent pathways for its breakdown were elucidated more than 50 years ago. In contrast, benzene was thought to be persistent under anoxic conditions until 25 years ago. Nevertheless, within the last 15 years, several benzene‐degrading cultures have been enriched under varying electron acceptor conditions in laboratories around the world, and organisms involved in anaerobic benzene degradation have been identified, indicating that anaerobic benzene degradation is a relevant environmental process. However, only a few benzene degraders have been isolated in pure culture so far, and they all use nitrate as an electron acceptor. In some highly enriched strictly anaerobic cultures, benzene has been described to be mineralized cooperatively by two or more different organisms. Despite great efforts, the biochemical mechanism by which the aromatic ring of benzene is activated in the absence of oxygen is still not fully elucidated; methylation, hydroxylation and carboxylation are discussed as likely reactions. This review summarizes the current knowledge about the ‘key players’ of anaerobic benzene degradation under different electron acceptor conditions and the possible pathway(s) of anaerobic benzene degradation. PMID:21450012

  18. Targeted protein degradation by PROTACs.

    PubMed

    Neklesa, Taavi K; Winkler, James D; Crews, Craig M

    2017-02-14

    Targeted protein degradation using the PROTAC technology is emerging as a novel therapeutic method to address diseases driven by the aberrant expression of a disease-causing protein. PROTAC molecules are bifunctional small molecules that simultaneously bind a target protein and an E3-ubiquitin ligase, thus causing ubiquitination and degradation of the target protein by the proteasome. Like small molecules, PROTAC molecules possess good tissue distribution and the ability to target intracellular proteins. Herein, we highlight the advantages of protein degradation using PROTACs, and provide specific examples where degradation offers therapeutic benefit over classical enzyme inhibition. Foremost, PROTACs can degrade proteins regardless of their function. This includes the currently "undruggable" proteome, which comprises approximately 85% of all human proteins. Other beneficial aspects of protein degradation include the ability to target overexpressed and mutated proteins, as well as the potential to demonstrate prolonged pharmacodynamics effect beyond drug exposure. Lastly, due to their catalytic nature and the pre-requisite ubiquitination step, an exquisitely potent molecules with a high degree of degradation selectivity can be designed. Impressive preclinical in vitro and in vivo PROTAC data have been published, and these data have propelled the development of clinically viable PROTACs. With the molecular weight falling in the 700-1000Da range, the delivery and bioavailability of PROTACs remain the largest hurdles on the way to the clinic. Solving these issues and demonstrating proof of concept clinical data will be the focus of many labs over the next few years.

  19. La replantation digitale, résultats et complications: étude d’une série de 18 cas

    PubMed Central

    Idrissi, Mohammed El; Elibrahimi, Abdelhalim; Shimi, Mohammed; Elmrini, Abdelmajid

    2016-01-01

    Les amputations digitales sont des lésions fréquentes, la majorité étant provoquée par des accidents de travail. Les techniques microchirurgicales représentent une alternative pour réparer ces amputations. L'objectif de ce travail est de rapporter notre expérience dans la replantation digitale à travers l'étude de 18 cas. Nous avons mené une étude rétrospective, étalée entre Juin 2013 et Janvier 2015, incluant 14 patients présentant une amputation totale ou subtotale des doigts. Nous avons inclus dans notre série toutes les replantations unidigitales et multidigitales réalisées en aval de l'insertion distale du tendon fléchisseur superficiel ainsi que les replantations digitales réalisées en amont de l'insertion distale du tendon fléchisseur superficiel. Nous avons opéré ces patients selon le procédé classique de réimplantation digitale. Cinq replantations ont été secondairement régularisées. Parmi les 18 replantations, huit replantions digitales ont favorablement évolué puisque la replantation a permis de restituer un secteur complet de mobilité passive et active du doigt opéré sans chirurgie de reprise et sans complication secondaire précoce et tardive. Dans notre étude nous avons noté des résultats satisfaisants, malgré les conditions difficiles notamment le conditionnement initial du doigt amputé, et le délai de prise en charge retardé. Le développement et la maîtrise de la microchirurgie a permis de changer le pronostic de ces amputations à retentissement fonctionnel et psychologique difficile, les résultats de notre série sont encourageants pour a mise en place d'un service SOS main au Maroc. PMID:27795781

  20. Performance Degradation of LSCF Cathodes

    SciTech Connect

    Alinger, Matthew

    2013-09-30

    This final report summarizes the progress made during the October 1, 2008 - September 30, 2013 period under Cooperative Agreement DE-NT0004109 for the U. S. Department of Energy/National Energy Technology Laboratory (USDOE/NETL) entitled “Performance Degradation of LSCF Cathodes”. The primary objective of this program is to develop a performance degradation mitigation path for high performing, cost-effective solid oxide fuel cells (SOFCs). Strategies to mitigate performance degradation are developed and implemented. In addition, thermal spray manufacturing of SOFCs is explored. Combined, this work establishes a basis for cost-effective SOFC cells.

  1. The Electric Car Challenge.

    ERIC Educational Resources Information Center

    Diehl, Brian E.

    1997-01-01

    Describes the Electric Car Challenge during which students applied methods of construction to build lightweight, strong vehicles that were powered by electricity. The activity required problem solving, sheet metal work, electricity, design, and construction skills. (JOW)

  2. Agricultural Electricity. Electric Motors. Student Manual.

    ERIC Educational Resources Information Center

    Benson, Robert T.

    Addressed to the student, this manual, which includes supplementary diagrams, discusses the following topics and principles: Electromagnetic fields, electromagnets, parts of an electric motor, determining speed of an electric motor, types of electric motors in common use (split-phase, capacitor, repulsion-induction, three-phase), the electric…

  3. Electrical safety guidelines

    SciTech Connect

    Not Available

    1993-09-01

    The Electrical Safety Guidelines prescribes the DOE safety standards for DOE field offices or facilities involved in the use of electrical energy. It has been prepared to provide a uniform set of electrical safety standards and guidance for DOE installations in order to affect a reduction or elimination of risks associated with the use of electrical energy. The objectives of these guidelines are to enhance electrical safety awareness and mitigate electrical hazards to employees, the public, and the environment.

  4. DOE handbook electrical safety

    SciTech Connect

    1998-01-01

    Electrical Safety Handbook presents the Department of Energy (DOE) safety standards for DOE field offices or facilities involved in the use of electrical energy. It has been prepared to provide a uniform set of electrical safety guidance and information for DOE installations to effect a reduction or elimination of risks associated with the use of electrical energy. The objectives of this handbook are to enhance electrical safety awareness and mitigate electrical hazards to employees, the public, and the environment.

  5. Analysis of thermal degradation of organic light-emitting diodes with infrared imaging and impedance spectroscopy.

    PubMed

    Kwak, Kiyeol; Cho, Kyoungah; Kim, Sangsig

    2013-12-02

    We propose a route to examine the thermal degradation of organic light-emitting diodes (OLEDs) with infrared (IR) imaging and impedance spectroscopy. Four different OLEDs with tris (8-hydroxyquinolinato) aluminum are prepared in this study for the analysis of thermal degradation. Our comparison of the thermal and electrical characteristics of these OLEDs reveals that the real-time temperatures of these OLEDs obtained from the IR images clearly correlate with the electrical properties and lifetimes. The OLED with poor electrical properties shows a fairly high temperature during the operation and a considerably short lifetime. Based on the correlation of the real-time temperature and the performance of the OLEDs, the impedance results suggest different thermal degradation mechanisms for each of the OLEDs. The analysis method suggested in this study will be helpful in developing OLEDs with higher efficiency and longer lifetime.

  6. Plant biomass degradation by fungi.

    PubMed

    Mäkelä, Miia R; Donofrio, Nicole; de Vries, Ronald P

    2014-11-01

    Plant biomass degradation by fungi has implications for several fields of science. The enzyme systems employed by fungi for this are broadly used in various industrial sectors such as food & feed, pulp & paper, detergents, textile, wine, and more recently biofuels and biochemicals. In addition, the topic is highly relevant in the field of plant pathogenic fungi as they degrade plant biomass to either gain access to the plant or as carbon source, resulting in significant crop losses. Finally, fungi are the main degraders of plant biomass in nature and as such have an essential role in the global carbon cycle and ecology in general. In this review we provide a global view on the development of this research topic in saprobic ascomycetes and basidiomycetes and in plant pathogenic fungi and link this to the other papers of this special issue on plant biomass degradation by fungi.

  7. Reductive Degradation: Versatile, Low Cost.

    ERIC Educational Resources Information Center

    Water and Sewage Works, 1979

    1979-01-01

    This article discusses the use of reductive degradation as an economical and effective treatment of chlorinated hydrocarbons. Comparisons with activated carbon treatment show lower capital equipment and treatment costs. (CS)

  8. Degradation of glycine and alanine on irradiated quartz.

    PubMed

    Pawlikowski, Maciej; Benko, Aleksandra; Wróbel, Tomasz P

    2013-04-01

    Recent researches suggest participation of minerals in the formation of life under primordial conditions. Among all of the minerals, quartz seems to be one of the most probable to take part in such processes. However, an external source of energy is needed, e.g. electric discharge. A device simulating the proposed conditions was designed and was used to simulate prebiotic conditions. Investigation of processes occurring during the stimulation of quartz with electric discharge was studied by means of Ultraviolet-visible (UV-VIS) spectroscopy, in order to monitor the generation kinetics of free radicals. Additionally, infrared spectroscopy was applied to identify chemical reaction products created in a solution of alanine or glycine, in the presence of quartz treated with electric discharge. Formation of increased amounts of free radicals, compared to experiments performed without quartz and/or amino acid, is reported, along with identification of possible degradation products of alanine. No synthetic reactions were observed.

  9. Degradation monitoring using probabilistic inference

    NASA Astrophysics Data System (ADS)

    Alpay, Bulent

    In order to increase safety and improve economy and performance in a nuclear power plant (NPP), the source and extent of component degradations should be identified before failures and breakdowns occur. It is also crucial for the next generation of NPPs, which are designed to have a long core life and high fuel burnup to have a degradation monitoring system in order to keep the reactor in a safe state, to meet the designed reactor core lifetime and to optimize the scheduled maintenance. Model-based methods are based on determining the inconsistencies between the actual and expected behavior of the plant, and use these inconsistencies for detection and diagnostics of degradations. By defining degradation as a random abrupt change from the nominal to a constant degraded state of a component, we employed nonlinear filtering techniques based on state/parameter estimation. We utilized a Bayesian recursive estimation formulation in the sequential probabilistic inference framework and constructed a hidden Markov model to represent a general physical system. By addressing the problem of a filter's inability to estimate an abrupt change, which is called the oblivious filter problem in nonlinear extensions of Kalman filtering, and the sample impoverishment problem in particle filtering, we developed techniques to modify filtering algorithms by utilizing additional data sources to improve the filter's response to this problem. We utilized a reliability degradation database that can be constructed from plant specific operational experience and test and maintenance reports to generate proposal densities for probable degradation modes. These are used in a multiple hypothesis testing algorithm. We then test samples drawn from these proposal densities with the particle filtering estimates based on the Bayesian recursive estimation formulation with the Metropolis Hastings algorithm, which is a well-known Markov chain Monte Carlo method (MCMC). This multiple hypothesis testing

  10. Investigation of rapid degradation in GaN-based blue laser diodes

    NASA Astrophysics Data System (ADS)

    Wen, Pengyan; Zhang, Shuming; Li, Deyao; Liu, Jianping; Zhang, Liqun; Shi, Dong; Zhou, Kun; Tian, Aiqin; Feng, Shiwei; Yang, Hui

    2016-11-01

    Investigation of the degradation modes in GaN-based blue laser diodes grown by metal organic chemical vapor deposition (MOCVD) is carried out. Early failure of the LDs happened at the initial stage of the aging. After analysis of the electrical and thermal characteristics, local degradation of the active region is observed. Further investigation on the microstructures of the local regions shows that the early failure of the LDs is due to the local structure damage with the formation of gallium metal.

  11. The Challenge of Time-Dependent Control of Both Processing and Performance of Materials at the Mesoscale, and the MaRIE Project

    NASA Astrophysics Data System (ADS)

    Barnes, Cris W.

    DOE and NNSA are recognizing a mission need for flexible and reduced-cost product-based solutions to materials through accelerated qualification, certification, and assessment. The science challenge lies between the nanoscale of materials and the integral device scale, at the middle or ''mesoscale'' where interfaces, defects, and microstructure determine the performance of the materials over the lifecycle of the intended use. Time-dependent control of the processing, structure and properties of materials at this scale lies at the heart of qualifying and certifying additive manufactured parts; experimental data of high fidelity and high resolution are necessary to discover the right physical mechanisms to model and to validate and calibrate those reduced-order models in codes on Exascale computers. The scientific requirements to do this are aided by a revolution in coherent imaging of non-periodic features that can be combined with scattering off periodic structures. This drives the need to require a coherent x-ray source, brilliant and high repetition rate, of sufficiently high energy to see into and through the mesoscale. The Matter-Radiation Interactions in Extremes (MaRIE) Project is a proposal to build such a very-high-energy X-ray Free Electron Laser.

  12. Nitrate pollution of groundwater in the alsatian plain (France)—A multidisciplinary study of an agricultural area: The Central Ried of the ill river

    NASA Astrophysics Data System (ADS)

    Bernhard, C.; Carbiener, R.; Cloots, A. R.; Froehlicher, R.; Schenck, Ch.; Zilliox, L.

    1992-09-01

    The area studied is part of the “Ried Central” of the Ill river (Middle Alsatian plain in northeastern France). This area is located mainly in the present floodplain of the Ill. The closeness of the water table to the surface results in quasi general soil hydromorphism. The economic constraints of the last two decades led to deep changes in agricultural activities in the study area. These have essentially involved a marked extension of intensive cultivation of grain corn at the expense of grasslands. The study of the influence of this change on the parallel increase in the concentration of nitrate in groundwater is only feasible when a multidisciplinary approach is adopted. The analyses carried out in the field and in the laboratory show that nitrate reduction occurs in gleyed or peaty horizons of hydromorphic soils. The aptitude and efficiency of the permanent ambient vegetation (alluvial forests and grasslands) in retaining nitrate must be emphasized. The amount of nitrate eliminated from the aquifer by rivers fed by this aquifer is considerable. This evacuation of nitrate into the Ill is a fine example of waste and illustrates the absurdity of the economic situation responsible for excessive nitrogen fertilization of farmlands. In determining hazard zones, this study also proposes practical solutions to the problem of nitrate pollution: diminution of land area under cultivation, reintroduction of grasslands, and a more judicious use of nitrogen manure.

  13. Degradation and resilience of soils

    PubMed Central

    Lal, R.

    1997-01-01

    Debate on global soil degradation, its extent and agronomic impact, can only be resolved through understanding of the processes and factors leading to establishment of the cause-effect relationships for major soils, ecoregions, and land uses. Systematic evaluation through long-term experimentation is needed for establishing quantitative criteria of (i) soil quality in relation to specific functions; (ii) soil degradation in relation to critical limits of key soil properties and processes; and (iii) soil resilience in relation to the ease of restoration through judicious management and discriminate use of essential input. Quantitative assessment of soil degradation can be obtained by evaluating its impact on productivity for different land uses and management systems. Interdisciplinary research is needed to quantify soil degradation effects on decrease in productivity, reduction in biomass, and decline in environment quality throught pollution and eutrophication of natural waters and emission of radiatively-active gases from terrestrial ecosystems to the atmosphere. Data from long-term field experiments in principal ecoregions are specifically needed to (i) establish relationships between soil quality versus soil degradation and soil quality versus soil resilience; (ii) identify indicators of soil quality and soil resilience; and (iii) establish critical limits of important properties for soil degradation and soil resilience. There is a need to develop and standardize techniques for measuring soil resilience.

  14. Abiotic degradation of plastic films

    NASA Astrophysics Data System (ADS)

    Ángeles-López, Y. G.; Gutiérrez-Mayen, A. M.; Velasco-Pérez, M.; Beltrán-Villavicencio, M.; Vázquez-Morillas, A.; Cano-Blanco, M.

    2017-01-01

    Degradable plastics have been promoted as an option to mitigate the environmental impacts of plastic waste. However, there is no certainty about its degradability under different environmental conditions. The effect of accelerated weathering (AW), natural weathering (NW) and thermal oxidation (TO) on different plastics (high density polyethylene, HDPE; oxodegradable high density polyethylene, HDPE-oxo; compostable plastic, Ecovio ® metalized polypropylene, PP; and oxodegradable metalized polypropylene, PP-oxo) was studied. Plastics films were exposed to AW per 110 hours; to NW per 90 days; and to TO per 30 days. Plastic films exposed to AW and NW showed a general loss on mechanical properties. The highest reduction in elongation at break on AW occurred to HDPE-oxo (from 400.4% to 20.9%) and was higher than 90% for HDPE, HDPE-oxo, Ecovio ® and PP-oxo in NW. No substantial evidence of degradation was found on plastics exposed to TO. Oxo-plastics showed higher degradation rates than their conventional counterparts, and the compostable plastic was resistant to degradation in the studied abiotic conditions. This study shows that degradation of plastics in real life conditions will vary depending in both, their composition and the environment.

  15. Working session 1: Tubing degradation

    SciTech Connect

    Kharshafdjian, G.; Turluer, G.

    1997-02-01

    A general introductory overview of the purpose of the group and the general subject area of SG tubing degradation was given by the facilitator. The purpose of the session was described as to {open_quotes}develop conclusions and proposals on regulatory and technical needs required to deal with the issues of SG tubing degradation.{close_quotes} Types, locations and characteristics of tubing degradation in steam generators were briefly reviewed. The well-known synergistic effects of materials, environment, and stress and strain/strain rate, subsequently referred to by the acronym {open_quotes}MESS{close_quotes} by some of the group members, were noted. The element of time (i.e., evolution of these variables with time) was emphasized. It was also suggested that the group might want to consider the related topics of inspection capabilities, operational variables, degradation remedies, and validity of test data, and some background information in these areas was provided. The presentation given by Peter Millet during the Plenary Session was reviewed; Specifically, the chemical aspects and the degradation from the secondary side of the steam generator were noted. The main issues discussed during the October 1995 EPRI meeting on secondary side corrosion were reported, and a listing of the potential SG tube degradations was provided and discussed.

  16. Condition Monitoring of Cables Task 3 Report: Condition Monitoring Techniques for Electric Cables

    SciTech Connect

    Villaran, M.; Lofaro, R.; na

    2009-11-30

    For more than 20 years the NRC has sponsored research studying electric cable aging degradation, condition monitoring, and environmental qualification testing practices for electric cables used in nuclear power plants. This report summarizes several of the most effective and commonly used condition monitoring techniques available to detect damage and measure the extent of degradation in electric cable insulation. The technical basis for each technique is summarized, along with its application, trendability of test data, ease of performing the technique, advantages and limitations, and the usefulness of the test results to characterize and assess the condition of electric cables.

  17. Quantify Degradation Rates and Mechanisms of PV Modules and Systems Installed in Florida Through Comprehensive Experimental and Theoretical Analysis (Poster)

    SciTech Connect

    Sorloaica-Hickman, N.; Davis, K.; Kurtz, S.; Jordan, D.

    2011-02-01

    The economic viability of photovoltaic (PV) technologies is inextricably tied to both the electrical performance and degradation rate of the PV systems, which are the generators of electrical power in PV systems. Over the past 15 years, performance data have been collected on numerous PV systems installed throughout the state of Florida and will be presented.

  18. Isolation and characterization of heavy polycyclic aromatic hydrocarbon-degrading bacteria adapted to electrokinetic conditions.

    PubMed

    Li, Fengmei; Guo, Shuhai; Hartog, Niels; Yuan, Ye; Yang, Xuelian

    2016-02-01

    Polycyclic aromatic hydrocarbon (PAH)-degrading bacteria capable of growing under electrokinetic conditions were isolated using an adjusted acclimation and enrichment procedure based on soil contaminated with heavy PAHs in the presence of an electric field. Their ability to degrade heavy PAHs under an electric field was individually investigated in artificially contaminated soils. The results showed that strains PB4 (Pseudomonas fluorescens) and FB6 (Kocuria sp.) were the most efficient heavy PAH degraders under electrokinetic conditions. They were re-inoculated into a polluted soil from an industrial site with a PAH concentration of 184.95 mg kg(-1). Compared to the experiments without an electric field, the degradation capability of Pseudomonas fluorescens and Kocuria sp. was enhanced in the industrially polluted soil under electrokinetic conditions. The degradation extents of total PAHs were increased by 15.4 and 14.0% in the electrokinetic PB4 and FB6 experiments (PB4 + EK and FB6 + EK) relative to the PB4 and FB6 experiments without electrokinetic conditions (PB4 and FB6), respectively. These results indicated that P. fluorescens and Kocuria sp. could efficiently degrade heavy PAHs under electrokinetic conditions and have the potential to be used for the electro-bioremediation of PAH-contaminated soil, especially if the soil is contaminated with heavy PAHs.

  19. Interfacial Degradation of Planar Lead Halide Perovskite Solar Cells.

    PubMed

    Guerrero, Antonio; You, Jingbi; Aranda, Clara; Kang, Yong Soo; Garcia-Belmonte, Germà; Zhou, Huanping; Bisquert, Juan; Yang, Yang

    2016-01-26

    The stability of perovskite solar cells is one of the major challenges for this technology to reach commercialization, with water believed to be the major degradation source. In this work, a range of devices containing different cathode metal contacts in the configuration ITO/PEDOT:PSS/MAPbI3/PCBM/Metal are fully electrically characterized before and after degradation caused by steady illumination during 4 h that induces a dramatic reduction in power conversion efficiency from values of 12 to 1.8%. We show that a decrease in performance and generation of the S-shape is associated with chemical degradation of the metal contact. Alternatively, use of Cr2O3/Cr as the contact enhances the stability, but modification of the energetic profile during steady illumination takes place, significantly reducing the performance. Several techniques including capacitance-voltage, X-ray diffraction, and optical absorption results suggest that the properties of the bulk perovskite layer are little affected in the device degradation process. Capacitance-voltage and impedance spectroscopy results show that the electrical properties of the cathode contact are being modified by generation of a dipole at the cathode that causes a large shift of the flat-band potential that modifies the interfacial energy barrier and impedes efficient extraction of electrons. Ionic movement in the perovskite layer changes the energy profile close to the contacts, modifying the energy level stabilization at the cathode. These results provide insights into the degradation mechanisms of perovskite solar cells and highlight the importance to further study the use of protecting layers to avoid the chemical reactivity of the perovskite with the external contacts.

  20. Micro electric propulsion feasibility

    NASA Technical Reports Server (NTRS)

    Aston, Graeme; Aston, Martha

    1992-01-01

    Miniature, 50 kg class, strategic satellites intended for extended deployment in space require an on-board propulsion capability to perform needed attitude control adjustments and drag compensation maneuvers. Even on such very small spacecraft, these orbit maintenance functions can be significant and result in a substantial propellant mass requirement. Development of advanced propulsion technology could reduce this propellant mass significantly, and thereby maximize the payload capability of these spacecraft. In addition, spacecraft maneuverability could be enhanced and/or multi-year mission lifetimes realized. These benefits cut spacecraft replacement costs, and reduce services needed to maintain the launch vehicles. For SDIO brilliant pebble spacecraft, a miniaturized hydrazine propulsion system provides both boost and divert thrust control. This type of propulsion system is highly integrated and is capable of delivering large thrust levels for short time periods. However, orbit maintenance functions such as drag make-up require only very small velocity corrections. Using the boost and/or divert thrusters for these small corrections exposes this highly integrated propulsion system to continuous on/off cycling and thereby increases the risk of system failure. Furthermore, since drag compensation velocity corrections would be orders of magnitude less than these thrusters were designed to deliver, their effective specific impulse would be expected to be lower when operated at very short pulse lengths. The net result of these effects would be a significant depletion of the on-board hydrazine propellant supply throughout the mission, and a reduced propulsion system reliability, both of which would degrade the interceptors usefulness. In addition to SDIO brilliant pebble spacecraft, comparably small spacecraft can be anticipated for other future strategic defense applications such as surveillance and communication. For such spacecraft, high capability and reliability

  1. Micro electric propulsion feasibility

    NASA Astrophysics Data System (ADS)

    Aston, Graeme; Aston, Martha

    1992-11-01

    Miniature, 50 kg class, strategic satellites intended for extended deployment in space require an on-board propulsion capability to perform needed attitude control adjustments and drag compensation maneuvers. Even on such very small spacecraft, these orbit maintenance functions can be significant and result in a substantial propellant mass requirement. Development of advanced propulsion technology could reduce this propellant mass significantly, and thereby maximize the payload capability of these spacecraft. In addition, spacecraft maneuverability could be enhanced and/or multi-year mission lifetimes realized. These benefits cut spacecraft replacement costs, and reduce services needed to maintain the launch vehicles. For SDIO brilliant pebble spacecraft, a miniaturized hydrazine propulsion system provides both boost and divert thrust control. This type of propulsion system is highly integrated and is capable of delivering large thrust levels for short time periods. However, orbit maintenance functions such as drag make-up require only very small velocity corrections. Using the boost and/or divert thrusters for these small corrections exposes this highly integrated propulsion system to continuous on/off cycling and thereby increases the risk of system failure. Furthermore, since drag compensation velocity corrections would be orders of magnitude less than these thrusters were designed to deliver, their effective specific impulse would be expected to be lower when operated at very short pulse lengths. The net result of these effects would be a significant depletion of the on-board hydrazine propellant supply throughout the mission, and a reduced propulsion system reliability, both of which would degrade the interceptors usefulness. In addition to SDIO brilliant pebble spacecraft, comparably small spacecraft can be anticipated for other future strategic defense applications such as surveillance and communication. For such spacecraft, high capability and reliability

  2. Interfacial Modifiers for Enhanced Stability and Reduced Degradation of Cu(In,Ga)Se2 Devices

    SciTech Connect

    Martin, Ina T.; Oyster, Tricia M.; Mansfield, Lorelle M.; Matthews, Rachael; Pentzer, Emily B.; French, Roger H.; Peshek, Timothy J.

    2016-11-21

    Transparent conductive oxide (TCO) degradation is a known failure mode in thin-film photovoltaic (PV) devices through mechanisms such as resistivity increase and delamination. Here we apply thin interfacial modifiers to aluminum-doped zinc oxide (AZO) to mitigate damp heat induced degradation of electrical performance. Additionally, we demonstrate that these modifiers can be applied to the AZO front contact of a Cu(In, Ga)Se2 device without significantly degrading the device performance, a promising step towards improving the lifetime performance.

  3. Electricity in the Atmosphere.

    ERIC Educational Resources Information Center

    Sampath, S.; Kumar, V. Sasi

    1991-01-01

    The theory of the atmospheric electric circuit and a discussion of the fair-weather electrical are presented. The ion concentration, mobility, conductivity, and electric field altitudinal profiles are explained. An outline of the electrical processes inside thunderstorms along with a description of the lightning strike are included. (Author)

  4. Characterization of ZnO-degraded varistors used in high-tension devices

    SciTech Connect

    Ramirez, M.A.; Maniette, Y.

    2007-06-05

    The effects of the degradation process on the structural, microstructural and electrical properties of ZnO-based varistors were analyzed. Rietveld refinement showed that the BiO{sub 2-x} phase is affected by the degradation process. Besides the changes in the spinel phase, the degradation process also affects the lattice microstrain in the ZnO phase. Scanning electron microscopy analysis showed electrode-melting failure, while wavelength dispersive X-ray spectroscopy qualitative analysis showed deficiency of oxygen species at the grain boundaries in the degraded samples. Atomic force microscopy using electrostatic mode force illustrated a decrease in the charge density at the grain boundaries of the degraded sample. Transmission electron microscopy showed submicrometric spinel grains embedded in a ZnO matrix, but their average grain size is smaller in the degraded sample than in the standard one. Long pulses appeared to be more harmful for the varistors' properties than short ones, causing higher leakage current values. The electrical characteristics of the degraded sample are partially restored after heat treatment in an oxygen-rich atmosphere.

  5. Degradation of Methylammonium Lead Iodide Perovskite Structures through Light and Electron Beam Driven Ion Migration.

    PubMed

    Yuan, Haifeng; Debroye, Elke; Janssen, Kris; Naiki, Hiroyuki; Steuwe, Christian; Lu, Gang; Moris, Michèle; Orgiu, Emanuele; Uji-I, Hiroshi; De Schryver, Frans; Samorì, Paolo; Hofkens, Johan; Roeffaers, Maarten

    2016-02-04

    Organometal halide perovskites show promising features for cost-effective application in photovoltaics. The material instability remains a major obstacle to broad application because of the poorly understood degradation pathways. Here, we apply simultaneous luminescence and electron microscopy on perovskites for the first time, allowing us to monitor in situ morphology evolution and optical properties upon perovskite degradation. Interestingly, morphology, photoluminescence (PL), and cathodoluminescence of perovskite samples evolve differently upon degradation driven by electron beam (e-beam) or by light. A transversal electric current generated by a scanning electron beam leads to dramatic changes in PL and tunes the energy band gaps continuously alongside film thinning. In contrast, light-induced degradation results in material decomposition to scattered particles and shows little PL spectral shifts. The differences in degradation can be ascribed to different electric currents that drive ion migration. Moreover, solution-processed perovskite cuboids show heterogeneity in stability which is likely related to crystallinity and morphology. Our results reveal the essential role of ion migration in perovskite degradation and provide potential avenues to rationally enhance the stability of perovskite materials by reducing ion migration while improving morphology and crystallinity. It is worth noting that even moderate e-beam currents (86 pA) and acceleration voltages (10 kV) readily induce significant perovskite degradation and alter their optical properties. Therefore, attention has to be paid while characterizing such materials using scanning electron microscopy or transmission electron microscopy techniques.

  6. Degradation of Methylammonium Lead Iodide Perovskite Structures through Light and Electron Beam Driven Ion Migration

    PubMed Central

    2016-01-01

    Organometal halide perovskites show promising features for cost-effective application in photovoltaics. The material instability remains a major obstacle to broad application because of the poorly understood degradation pathways. Here, we apply simultaneous luminescence and electron microscopy on perovskites for the first time, allowing us to monitor in situ morphology evolution and optical properties upon perovskite degradation. Interestingly, morphology, photoluminescence (PL), and cathodoluminescence of perovskite samples evolve differently upon degradation driven by electron beam (e-beam) or by light. A transversal electric current generated by a scanning electron beam leads to dramatic changes in PL and tunes the energy band gaps continuously alongside film thinning. In contrast, light-induced degradation results in material decomposition to scattered particles and shows little PL spectral shifts. The differences in degradation can be ascribed to different electric currents that drive ion migration. Moreover, solution-processed perovskite cuboids show heterogeneity in stability which is likely related to crystallinity and morphology. Our results reveal the essential role of ion migration in perovskite degradation and provide potential avenues to rationally enhance the stability of perovskite materials by reducing ion migration while improving morphology and crystallinity. It is worth noting that even moderate e-beam currents (86 pA) and acceleration voltages (10 kV) readily induce significant perovskite degradation and alter their optical properties. Therefore, attention has to be paid while characterizing such materials using scanning electron microscopy or transmission electron microscopy techniques. PMID:26804213

  7. Compendium of photovoltaic degradation rates: Photovoltaic degradation rates

    SciTech Connect

    Jordan, Dirk C.; Kurtz, Sarah R.; VanSant, Kaitlyn; Newmiller, Jeff

    2016-02-07

    Published data on photovoltaic (PV) degradation measurements were aggregated and re-examined. The subject has seen an increased interest in recent years resulting in more than 11 000 degradation rates in almost 200 studies from 40 different countries. As studies have grown in number and size, we found an impact from sampling bias attributable to size and accuracy. Because of the correlational nature of this study we examined the data in several ways to minimize this bias. We found median degradation for x-Si technologies in the 0.5-0.6%/year range with the mean in the 0.8-0.9%/year range. Hetero-interface technology (HIT) and microcrystalline silicon (..mu..c-Si) technologies, although not as plentiful, exhibit degradation around 1%/year and resemble thin-film products more closely than x-Si. Several studies showing low degradation for copper indium gallium selenide (CIGS) have emerged. Higher degradation for cadmium telluride (CdTe) has been reported, but these findings could reflect a convolution of less accurate studies and longer stabilization periods for some products. Significant deviations for beginning-of-life measurements with respect to nameplate rating have been documented over the last 35 years. Therefore, degradation rates that use nameplate rating as reference may be significantly impacted. Studies that used nameplate rating as reference but used solar simulators showed less variation than similar studies using outdoor measurements, even when accounting for different climates. This could be associated with confounding effects of measurement uncertainty and soiling that take place outdoors. Hotter climates and mounting configurations that lead to sustained higher temperatures may lead to higher degradation in some, but not all, products. Wear-out non-linearities for the worst performing modules have been documented in a few select studies that took multiple measurements of an ensemble of modules during the lifetime of the system. However, the majority

  8. Hydrocarbon degradation by antarctic bacteria

    SciTech Connect

    Cavanagh, J.A.E.; Nichols, P.D.; McMeekin, T.A.; Franzmann, P.D.

    1996-12-31

    Bacterial cultures obtained from sediment samples collected during a trial oil spill experiment conducted at Airport beach, Eastern Antarctica were selectively enriched for n-alkane-degrading and phenanthrenedegrading bacteria. Samples were collected from a control site and sites treated with different hydrocarbon mixtures - Special Antarctic blend (SAB), BP-Visco and orange roughy oils. One set of replicate sites was also treated with water from Organic Lake which had previously been shown to contain hydrocarbon-degrading bacteria. No viable bacteria were obtained from samples collected from sites treated with orange roughy oil. Extensive degradation of n-alkanes by enrichment cultures obtained from sites treated with SAB and BP-Visco occurred at both 25{degrees}C and 10{degrees}C. Extensive degradation of phenanthrene also occurred in enrichment cultures from these sites grown at 25{degrees}C. Concurrent increases of polar lipid in these cultures were also observed. The presence of 1,4-naphthaquinone and 1-naphthol during the growth of the cultures on phenanthrene is unusual and warrants further investigation of the mechanism of phenanthrene-degradation by these Antarctic bacteria.

  9. Gas-insulated substation spacer surface degradation analysis

    SciTech Connect

    Chu, F.Y.; Braun, J.M. )

    1990-06-01

    The objective of the project was to develop surface analysis techniques which can correlate the performance of spacers in SF{sub 6} insulated switchgear with changes in their dielectric and chemical characteristics after exposure to SF{sub 6} arcing byproducts and low energy flashovers. Critical material parameters responsible for spacer performance were investigated by optical and scanning electron microscopy, electron spectroscopy for chemical analysis, thermogravimetric analysis and electrical surface resistance measurements. Results related to arc byproduct resistance and tracking resistance of seven types of filled epoxy spacer materials are presented. Degradation mechanisms have been proposed to explain the differing material behaviour. The study shows that the interaction of certain types of filler and resin systems with the SF{sub 6} spark and the decomposed gas is responsible for the degradation in impulse withstand performance. A practical technique using surface electrical resistance to detect degraded spacer after exposure to large quantities of arc byproducts has been developed and the construction of a probe for spacer surface assessment was described. 15 refs., 28 figs., 8 tabs.

  10. Evolution de la résistance aux antibiotiques des entérobactéries isolées à l'Hôpital Général de Douala de 2005 à 2012

    PubMed Central

    Ebongue, Cécile Okalla; Tsiazok, Martial Dongmo; Mefo'o, Jean Pierre Nda; Ngaba, Guy Pascal; Beyiha, Gérard; Adiogo, Dieudonné

    2015-01-01

    Introduction Cette étude vise à déterminer le profil de résistance aux antibiotiques des entérobactéries isolées à l'Hôpital Général de Douala (Cameroun) et analyser leur évolution dans le temps. Méthodes Etude rétrospective, sur une période de huit ans (2005 - 2012), portant sur l'ensemble des souches d'entérobactéries isolées chez les malades ambulatoires et hospitalisés. Les prélèvements ont été analysés au laboratoire de bactériologie de l'Hôpital Général de Douala. Résultats Les entérobactéries étaient les germes les plus fréquents sur l'ensemble des souches isolées. Nous avons noté une prédominance d’Escherichia coli (48,5%) et de Klebsiella pneumoniae (32,8%). Pendant la période d’étude, nous avons observé des taux de résistance élevés aux principales classes d'antibiotiques, et une augmentation entre 2005 et 2012 de 29,1% à 51,6% pour les céphalosporines de troisième génération, de 29,2% à 44% pour la ciprofloxacine. L'imipénème, l'amikacine et la fosfomycine étaient les molécules les plus actives avec respectivement 1,3%, 12,9% et 13,4% des souches d'entérobactéries résistantes. Conclusion L’évolution des résistances des entérobactéries aux antibiotiques est un phénomène réel dans la ville de Douala. Il expose à des difficultés de prise en charge thérapeutique des infections. Lamaitrise actuelle de ce phénomène est une véritable urgence et nécessite une implication des pouvoirs publics. Des tests spécifiques de recherche des bétalactamases à spectre élargi (BLSE) et AmpC doivent être mis en place dans nos laboratoires afin de mettre en évidence les différents phénotypes de résistances. PMID:26140070

  11. Water purification by electrical discharges

    NASA Astrophysics Data System (ADS)

    Arif Malik, Muhammad; Ghaffar, Abdul; Akbar Malik, Salman

    2001-02-01

    There is a continuing need for the development of effective, cheap and environmentally friendly processes for the disinfection and degradation of organic pollutants from water. Ozonation processes are now replacing conventional chlorination processes because ozone is a stronger oxidizing agent and a more effective disinfectant without any side effects. However, the fact that the cost of ozonation processes is higher than chlorination processes is their main disadvantage. In this paper recent developments targeted to make ozonation processes cheaper by improving the efficiency of ozone generation, for example, by incorporation of catalytic packing in the ozone generator, better dispersion of ozone in water and faster conversion of dissolved ozone to free radicals are described. The synthesis of ozone in electrical discharges is discussed. Furthermore, the generation and plasma chemical reactions of several chemically active species, such as H2O2, Obullet, OHbullet, HO2bullet, O3*, N2*, e-, O2-, O-, O2+, etc, which are produced in the electrical discharges are described. Most of these species are stronger oxidizers than ozone. Therefore, water treatment by direct electrical discharges may provide a means to utilize these species in addition to ozone. Much research and development activity has been devoted to achieve these targets in the recent past. An overview of these techniques and important developments that have taken place in this area are discussed. In particular, pulsed corona discharge, dielectric barrier discharge and contact glow discharge electrolysis techniques are being studied for the purpose of cleaning water. The units based on electrical discharges in water or close to the water level are being tested at industrial-scale water treatment plants.}

  12. 75 FR 80391 - Electric Reliability Organization Interpretations of Interconnection Reliability Operations and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-22

    ... Electrical and Electronics Engineers, Inc. (IEEE) definition of degraded as ``the inability of an item to... request for interpretation at 4-5 (citing full IEEE definitions of degraded: ``A failure that is gradual... the ability of an item to perform its required function.'' IEEE 100, The Authoritative Dictionary...

  13. Clad Degradation - FEPs Screening Arguments

    SciTech Connect

    E. Siegmann

    2004-03-17

    The purpose of this report is to document the screening of the cladding degradation features, events, and processes (FEPs) for commercial spent nuclear fuel (CSNF). This report also addresses the effect of some FEPs on both the cladding and the CSNF, DSNF, and HLW waste forms where it was considered appropriate to address the effects on both materials together. This report summarizes the work of others to screen clad degradation FEPs in a manner consistent with, and used in, the Total System Performance Assessment-License Application (TSPA-LA). This document was prepared according to ''Technical Work Plan for Waste Form Degradation Modeling, Testing, and Analyses in Support of LA'' (BSC 2004a [DIRS 167796]).

  14. Ionomer Degradation in Electrodes of PEM Fuel Cell

    SciTech Connect

    Borup, Rodney L.

    2011-01-01

    Although PEMFC Membrane Electrode Assembly (MEA) durability related studies have increased dramatically since 2004, studies on ionomer degradation of the composite electrodes has received far less attention than that of the proton exchange membranes, electrocatalysts, and catalyst supports. The catalyst layer ionomer unavoidably gets involved in other components degradation processes since it is subjected to exposure to different operating effects, including the presence of the catalyst, catalyst support, and the porous nature of the electrode layer which includes 2-phase flow. PEMFC durability issues cannot be fully resolved without understanding the contribution of ionomer degradation in electrode to the performance decay in life time. However, addressing the impact of changes to the catalyst layer ionomer during durability tests is experimentally difficult mainly because of the need to separate the ionomer in the electrode from other components during chemical, electrical and materials characterization. The catalyst layer ionomer is essentially chemically identical to the membrane ionomeric material, and is composed of low atomic number elements, making characterization difficult. In the present work, MEAs with different Nafion ionomer types: stabilized and non-stablized ionomer in the electrode layer (Type I) and mixed membrane/ionomer MEAs (Type II) were designed to separate ionomer degradation from membrane degradation, as shown in Figure (1a) and (b) respectively. Stabilized and non stabilized ionomers were 5% Nafion{reg_sign} solutions (Ion Power, New Castle, Delaware). The non-stabilized version is the typical Nafion chemical structure with carboxylic acid (-COOH) end groups; these end groups are thought to be a susceptible point of degradative peroxide attack. The stabilized version replaces the -COOH end groups with -CF{sub 3} end groups to prevent peroxide attack at the end groups. Type I MEAs were designed to compare ionomer degradation and its effect

  15. FOREWORD: Focus on the Degradation and Stability of Polymers

    NASA Astrophysics Data System (ADS)

    Terano, Minoru

    2008-06-01

    Modern society is so reliant on polymers that products incorporating these macromolecules are almost 'invisible'. Polymers are indispensable materials used for manufacturing compact disks, clothes, lightweight airplanes, automobiles, footware and even the humble polystyrene boxes for packing our favorite hamburgers and fries. But, like many other materials, polymers degrade and become unstable, so a deeper understanding of the physical mechanisms responsible for degradation is necessary to address issues such as potential applications, recycling and the impact of polymer-products on the environment. In particular, polymers are highly vulnerable to oxidative degradation at elevated temperatures and in sunlight. Unfortunately, in spite of extensive research on polymer degradation, our knowledge is still incomplete. The analysis of polymer degradation and stability has recently become harder and more complicated because of the wider range of polymer applications, including blends and composites. Notably, composites with nanofillers are being studied for automotive, electrical and other industrial applications. With this background, the 1st International Symposium on Ultimate Stability of NanoStructured Polymers and Composites (NT2007) was held in October at the Japan Advanced Institute of Science and Technology in Ishikawa Prefecture. The meeting provided a forum to discuss advanced research achievements to resolve problems in this field of research. The papers selected for this focus issue describe recent discoveries on the stability, weatherability and flame retardancy of polymers, as well as providing an insight into degradation mechanisms of nanostructured polymers and composites. We hope that this focus issue will serve as a timely source of information about one of the most important topics in polymer science and related technologies.

  16. Enzyme-catalyzed degradation of carbon nanomaterials

    NASA Astrophysics Data System (ADS)

    Kotchey, Gregg P.

    Carbon nanotubes and graphene, the nanoscale sp 2 allotropes of carbon, have garnered widespread attention as a result of their remarkable electrical, mechanical, and optical properties and the promise of new technologies that harness these properties. Consequently, these carbon nanomaterials (CNMs) have been employed for diverse applications such as electronics, sensors, composite materials, energy conversion devices, and nanomedicine. The manufacture and eventual disposal of these products may result in the release of CNMs into the environment and subsequent exposure to humans, animals, and vegetation. Given the possible pro-inflammatory and toxic effects of CNMs, much attention has been focused on the distribution, toxicity, and persistence of CNMs both in living systems and the environment. This dissertation will guide the reader though recent studies aimed at elucidating fundamental insight into the persistence of CNMs such as carbon nanotubes (CNTs) and graphene derivatives (i.e., graphene oxide and reduced graphene oxide). In particular, in-testtube oxidation/degradation of CNMs catalyzed by peroxidase enzymes will be examined, and the current understanding of the mechanisms underlying these processes will be discussed. Finally, an outlook of the current field including in vitro and in vivo biodegradation experiments, which have benefits in terms of human health and environmental safety, and future directions that could have implications for nanomedical applications such as imaging and drug delivery will be presented. Armed with an understanding of how and why CNMs undergo enzyme-catalyzed oxidation/biodegradation, researchers can tailor the structure of CNMs to either promote or inhibit these processes. For example, in nanomedical applications such as drug delivery, the incorporation of carboxylate functional groups could facilitate biodegradation of the nanomaterial after delivery of the cargo. Also, the incorporation of CNMs with defect sites in consumer

  17. Degradation Physics of High Power LEDs in Outdoor Environment and the Role of Phosphor in the degradation process

    NASA Astrophysics Data System (ADS)

    Singh, Preetpal; Tan, Cher Ming

    2016-04-01

    A moisture- electrical – temperature (MET) test is proposed to evaluate the outdoor reliability of high power blue LEDs, with and without phosphor, and to understand the degradation physics of LEDs under the environment of combined humidity, temperature and electrical stresses. The blue LEDs with phosphor will be the high power white LEDs. Scanning acoustic microscopy is used to examine the resulted delamination during this test for the LEDs. The degradation mechanisms of blue LEDs (LEDs without phosphor) and white LEDs (LEDs with phosphor) are found to be different, under both the power on (i.e. with 350 mA through each LED) and power off (i.e. without current supply) conditions. Difference in the coefficient of thermal expansion between the molding part and the lens material as well as the heat generated by the phosphor layer are found to account for the major differences in the degradation mechanisms observed. The findings indicate that the proposed MET test is necessary for the LED industry in evaluating the reliability of LEDs under practical outdoor usage environment.

  18. Degradation Physics of High Power LEDs in Outdoor Environment and the Role of Phosphor in the degradation process.

    PubMed

    Singh, Preetpal; Tan, Cher Ming

    2016-04-07

    A moisture- electrical - temperature (MET) test is proposed to evaluate the outdoor reliability of high power blue LEDs, with and without phosphor, and to understand the degradation physics of LEDs under the environment of combined humidity, temperature and electrical stresses. The blue LEDs with phosphor will be the high power white LEDs. Scanning acoustic microscopy is used to examine the resulted delamination during this test for the LEDs. The degradation mechanisms of blue LEDs (LEDs without phosphor) and white LEDs (LEDs with phosphor) are found to be different, under both the power on (i.e. with 350 mA through each LED) and power off (i.e. without current supply) conditions. Difference in the coefficient of thermal expansion between the molding part and the lens material as well as the heat generated by the phosphor layer are found to account for the major differences in the degradation mechanisms observed. The findings indicate that the proposed MET test is necessary for the LED industry in evaluating the reliability of LEDs under practical outdoor usage environment.

  19. Degradation Physics of High Power LEDs in Outdoor Environment and the Role of Phosphor in the degradation process

    PubMed Central

    Singh, Preetpal; Tan, Cher Ming

    2016-01-01

    A moisture- electrical – temperature (MET) test is proposed to evaluate the outdoor reliability of high power blue LEDs, with and without phosphor, and to understand the degradation physics of LEDs under the environment of combined humidity, temperature and electrical stresses. The blue LEDs with phosphor will be the high power white LEDs. Scanning acoustic microscopy is used to examine the resulted delamination during this test for the LEDs. The degradation mechanisms of blue LEDs (LEDs without phosphor) and white LEDs (LEDs with phosphor) are found to be different, under both the power on (i.e. with 350 mA through each LED) and power off (i.e. without current supply) conditions. Difference in the coefficient of thermal expansion between the molding part and the lens material as well as the heat generated by the phosphor layer are found to account for the major differences in the degradation mechanisms observed. The findings indicate that the proposed MET test is necessary for the LED industry in evaluating the reliability of LEDs under practical outdoor usage environment. PMID:27052103

  20. Cellobiose dehydrogenase in cellulose degradation

    SciTech Connect

    Eriksson, L.; Igarashi, Kiyohiko; Samejima, Masahiro

    1996-10-01

    Cellobiose dehydrogenase is produced by a variety of fungi. Although it was already discovered during the 70`s, it`s role in cellulose and lignin degradation is yet ambiguous. The enzyme contains both heme and FAD as prosthetic groups, and seems to have a domain specifically designed to bind the enzyme to cellulose. It`s affinity to amorphous cellulose is higher than to crystalline cellulose. We will report on the binding behavior of the enzyme, its usefulness in elucidation of cellulose structures and also, possibilities for applications such as its use in measuring individual and synergistic mechanisms for cellulose degradation by endo- and exo-glucanases.

  1. Redox control of protein degradation

    PubMed Central

    Pajares, Marta; Jiménez-Moreno, Natalia; Dias, Irundika H.K.; Debelec, Bilge; Vucetic, Milica; Fladmark, Kari E.; Basaga, Huveyda; Ribaric, Samo; Milisav, Irina; Cuadrado, Antonio

    2015-01-01

    Intracellular proteolysis is critical to maintain timely degradation of altered proteins including oxidized proteins. This review attempts to summarize the most relevant findings about oxidant protein modification, as well as the impact of reactive oxygen species on the proteolytic systems that regulate cell response to an oxidant environment: the ubiquitin-proteasome system (UPS), autophagy and the unfolded protein response (UPR). In the presence of an oxidant environment, these systems are critical to ensure proteostasis and cell survival. An example of altered degradation of oxidized proteins in pathology is provided for neurodegenerative diseases. Future work will determine if protein oxidation is a valid target to combat proteinopathies. PMID:26381917

  2. Degradation of alkanes by bacteria.

    PubMed

    Rojo, Fernando

    2009-10-01

    Pollution of soil and water environments by crude oil has been, and is still today, an important problem. Crude oil is a complex mixture of thousands of compounds. Among them, alkanes constitute the major fraction. Alkanes are saturated hydrocarbons of different sizes and structures. Although they are chemically very inert, most of them can be efficiently degraded by several microorganisms. This review summarizes current knowledge on how microorganisms degrade alkanes, focusing on the biochemical pathways used and on how the expression of pathway genes is regulated and integrated within cell physiology.

  3. Caractérisation et préconcentration granulométrique de la matière feldspathique d'Ain-Barbar, Algérie

    NASA Astrophysics Data System (ADS)

    Djouama, M. C.; Bounouala, M.; Ain-Souya, A.; Ghers, M.

    2005-05-01

    Les feldspaths sont répandus dans l'écorce terrestre mais seuls les feldspaths potassiques et sodiques sont très recherchés dans l'industrie céramique et verrière. Pour qu'ils soient utilisables, ces matériaux doivent contenir très peu d'impuretés nocives de fer et surtout de silice. La carrière d'Ain-Barbar exploite la matière feldspathique de teneurs moyennes respectives 74,5% SiO{2}, 9,5% 12,75% Al{2}O{3}, 1,30% Fe{2}O{3} et 9,5 K{2}O (0,90% Na{2}O). Toutefois, on constate un taux très élevé en quartz ce qui diminue la valeur du produit marchand et une teneur élevée en fer ce qui donne au produit fabriqué, des aspects de coloration le rendant impropre à la commercialisation. A cet effet, une caractérisation minéralogique et chimique a été réalisée sur une série d'échantillons prélevés du site d'extraction de la substance utile. Des essais de préconcentration granulométrique ont montré qu'un classement dimensionnel peut offrir une qualité de produits acceptables par les céramistes.

  4. Extracts of impact breccia samples from Sudbury, Gardnos, and Ries impact craters and the effects of aggregation on C 60 detection

    NASA Astrophysics Data System (ADS)

    Elsila, Jamie E.; de Leon, Nathalie P.; Plows, Fiona L.; Buseck, Peter R.; Zare, Richard N.

    2005-06-01

    Fullerenes have been detected in carbonaceous chondrite meteorites and in breccia samples from meteorite impact craters, but questions have been raised about contradictory results from similar samples and the sensitivities and accuracies of different analytical methods. We analyzed samples from three impact craters and detected C 60 in samples from several locations; we also observed differences in the detection capabilities of various analytical techniques used in the search for fullerenes. The presence of C 60 in rocks from the Onaping Formation of the Sudbury impact crater was confirmed. Low levels of C 60 were also detected for the first time in samples from the Gardnos (Norway) and Ries (Germany) impact structures. We detected C 60 in these samples using surface-enhanced laser desorption/ ionization (SELDI), but the related technique of microprobe laser-desorption, laser-ionization mass spectrometry (μL 2MS) did not observe C 60 above detection limits. We attribute the absence of μL 2MS signal to aggregate formation caused by phthalic acid esters, which appear to easily contaminate samples either during storage or demineralization in plastic containers. The μL 2MS technique is incapable of detecting aggregated C 60, but aggregation does not suppress detection in SELDI. Phthalate-induced aggregation did, however, enhance SELDI detection of C 60 in some cases, and we suggest that this enhancement may help explain previously reported differences in C 60 detection from natural samples between laser desorption mass spectrometry (LDMS, a technique analogous to SELDI that has detected fullerenes in meteorite and impact breccia samples) and high-pressure liquid chromatography (HPLC). This work highlights the effects of phthalates and other indigenous compounds or contaminants on certain mass spectrometric techniques and lends support to the idea that several complementary analytical methods should be employed to investigate complex natural samples.

  5. Ries Bunte Breccia revisited: Indications for the presence of water in Itzing and Otting drill cores and implications for the emplacement process

    NASA Astrophysics Data System (ADS)

    Pietrek, Alexa; Kenkmann, Thomas

    2016-07-01

    We reassessed two drill cores of the Bunte Breccia deposits of the Ries crater, Germany. The objectives of our study were the documentation of evidence for water in the Bunte Breccia, the evaluation of how that water influenced the emplacement processes, and from which preimpact water reservoir it was derived. The Bunte Breccia in both cores can be structured into a basal layer composed mainly of local substrate material, overlain by texturally and compositionally diverse, crater-derived breccia units. The basal layer is composed of the youngest sediments (Tertiary clays and Upper Jurassic limestone) and has a razor-sharp boundary to the upper breccia units, which are composed of older rocks of Upper Jurassic to Upper Triassic age. Sparse material exchange occurred between the basal layer and the rest of the Bunte Breccia. Fluids predominantly came from the Tertiary and the Upper Triassic sandstone formation. In the basal layer, Tertiary clays were subjected to intense, ductile deformation, indicating saturation with water. This suggests that water was mixed into the matrix, creating a fluidized basal layer with a strong shear localization. In the upper units, Upper Triassic sandstones are intensely deformed by granular flow. The texture requires that the rocks were disaggregated into granular sand. Vaporization of pore water probably aided fragmentation of these rocks. In the Otting core, hot suevite (T > 600 °C) covered the Bunte Breccia shortly after its emplacement. Vertically oriented gas escape pipes in suevite partly emanate directly at the contact to the Bunte Breccia. They indicate that the Bunte Breccia contained a substantial amount of water in the upper part that was vaporized and escaped through these vents.

  6. Degradation and acute toxicity studies of degradable implant materials

    NASA Astrophysics Data System (ADS)

    Taylor, Michelle Suzette

    The present study investigated the acute toxicities of the degradation product components of six degradable polymers, the acute toxicities of nine metallic ions and accelerated degradation of one degradable polymer. Prior to these studies, the effect of the anticipated test conditions on the Microtox acute toxicity assay was determined. It was shown that the Microtox is unaffected by pH of water within the range of 5 to 10 and that the test is unaffected by tris buffer at physiologic pH and concentration. The toxicity and rates of degradation of poly(glycolic acid), PGA; two samples of poly(L-lactic acid), PLLA; samples of different molecular weights, poly(caprolactone), PCL; poly(ortho ester), POE; and poly(hydroxybutyrate-cohydroxyvalerate), PHBV, were compared, along with the toxicity of their degradation product components. The toxic concentrations ranged from 100 muM (lactic acid) to 125,000 muM (pentaerythritol). The degradation product components in order of most toxic to least toxic are lactic acid, caproic acid, glycolic acid, cyclohexanedimethanol, propionic acid, hydroxybutyric acid, 1,6-hexanediol, pentaerythritol dipropionate, pentaerythritol and hydroxyvaleric acid. Acute toxicity was determined for metallic ions in water and buffer. The toxic concentrations ranged from 33 muM (Tisp{4+} in water) to 3,580 muM (Wsp{6+} in buffer). The four most toxic ions in water (Tisp{4+}, Mosp{5+}, Fesp{3+}, Crsp{3+}) caused solution pH to decrease markedly. The six other ions (Vasp{3+}, Cosp{3+}, Alsp{3+,} Tisp{4+} adjusted to pH 6.1, Nisp{2+} and Wsp{6+}) markedly. The six other ions (Vasp{3+}, Cosp{3+}, Alsp{3+}, Tisp{4+} adjusted to pH 6.1, Nisp{2+} and Wsp{6+}) did not appreciably affect pH. In buffer, Alsp{3+}, Nisp{2+}, Wsp{6+} and Vsp{3+} became much less toxic, suggesting formation of complexes. In general the least toxic ions do not create an acid environment and/or do form protective complexes. PHBV has good mechanical properties and, compared with the

  7. Eliminating degradation in solid oxide electrochemical cells by reversible operation.

    PubMed

    Graves, Christopher; Ebbesen, Sune Dalgaard; Jensen, Søren Højgaard; Simonsen, Søren Bredmose; Mogensen, Mogens Bjerg

    2015-02-01

    One promising energy storage technology is the solid oxide electrochemical cell (SOC), which can both store electricity as chemical fuels (electrolysis mode) and convert fuels to electricity (fuel-cell mode). The widespread use of SOCs has been hindered by insufficient long-term stability, in particular at high current densities. Here we demonstrate that severe electrolysis-induced degradation, which was previously believed to be irreversible, can be completely eliminated by reversibly cycling between electrolysis and fuel-cell modes, similar to a rechargeable battery. Performing steam electrolysis continuously at high current density (1 A cm(-2)), initially at 1.33 V (97% energy efficiency), led to severe microstructure deterioration near the oxygen-electrode/electrolyte interface and a corresponding large increase in ohmic resistance. After 4,000 h of reversible cycling, however, no microstructural damage was observed and the ohmic resistance even slightly improved. The results demonstrate the viability of applying SOCs for renewable electricity storage at previously unattainable reaction rates, and have implications for our fundamental understanding of degradation mechanisms that are usually assumed to be irreversible.

  8. Degradation in organic light emitting devices

    NASA Astrophysics Data System (ADS)

    Dinh, Vincent Vinh

    This thesis is about the fundamental causes of degradation in tris(8-Hydroxyquinoline) Aluminum (Alq3)-based organic light emitting diodes (OLEDs). Degradation typically occurs when a current is forced through an insulating material. Since the insulator does not support conduction waves (in its ground state), chemical restructuring must occur to accommodate the current. OLEDs have many technical advantages over the well known semiconductor-based light emitting diodes (LEDs). OLEDs have quantum efficiencies ˜1% (˜10 times higher than the LEDs), and operational power thresholds ˜.05mW (˜100 lower than the LEDs). OLEDs are preferred in power limited and portable devices; devices such as laptops and displays consume ˜1/4 of the supplied power---any power saving is significant. Other advantages, like better compliance to curved surfaces and ease of fabrication, give the OLEDs an even greater edge over the LEDs. OLEDs must have at least comparable or better lifetimes to remain attractive. Typical OLEDs last several 100hrs compared to the several 1000hrs for the LEDs. For reliable OLED application, it is necessary to understand the above breakdown mechanism. In this thesis, we attempt to understand the breakdown by looking at how OLEDs are made, how they work, and when they don't. In the opening sections, we give an overview of OLEDs and LEDs, especially how sustained luminescence is achieved through current circulation. Then in Chapter 2, we look at the basic components in the OLEDs. In Chapter 3 we look at how a hole material (like poly-vinyl carbazole or PVK) establishes an excitonic environment for the sustained luminescence in Alq3. We then approximate how potential is distributed when a simple luminescence system is in operation. In Chapter 4, we look at ways of measuring this distribution via the OLED impedance. Finally in Chapter 5, we look at the OLED stability under light emission conditions via PVK and Alq3 photoemission and photoabsorption spectra

  9. Luminescence of Degraded Si-SiO2 Structures

    NASA Astrophysics Data System (ADS)

    Baraban, A. P.; Dmitriev, V. A.; Gadzhala, A. A.

    2014-09-01

    Possibilities of using electroluminescence (EL) and cathodoluminescence (CL) in the spectral range 250-800 nm to investigate physical-chemical processes taking place in Si-SiO2 structures as a result of extreme external actions (strong electric fields or γ-radiation) are considered. It is found that degradation processes along with changes in the electrophysical characteristics of Si-SiO2 structures are revealed in changes in the luminescence spectra, especially in the red region. The similarity of the changes in the CL and EL spectra of Si-SiO2 structures exposed to field and radiation points to a similarity in the processes taking place during degradation, which is confirmed by the qualitative similarity of the changes in the charge characteristics. The near-invariance of the spectral composition of the luminescence is an indication that the processes taking place during degradation do not lead to the formation of new luminescence centers, but modify the concentration of already existing biographical defects. This is evidence of the existence of a direct link between resistance to degradation and the technology of formation of the oxide layer on the silicon surface.

  10. Electric arc saw apparatus

    DOEpatents

    Deichelbohrer, Paul R [Richland, WA

    1986-01-01

    A portable, hand held electric arc saw has a small frame for supporting an electrically conducting rotary blade which serves as an electrode for generating an electric arc to erode a workpiece. Electric current is supplied to the blade by biased brushes and a slip ring which are mounted in the frame. A pair of freely movable endless belts in the form of crawler treads stretched between two pulleys are used to facilitate movement of the electric arc saw. The pulleys are formed of dielectric material to electrically insulate the crawler treads from the frame.

  11. Trapped charge-driven degradation of perovskite solar cells

    NASA Astrophysics Data System (ADS)

    Ahn, Namyoung; Kwak, Kwisung; Jang, Min Seok; Yoon, Heetae; Lee, Byung Yang; Lee, Jong-Kwon; Pikhitsa, Peter V.; Byun, Junseop; Choi, Mansoo

    2016-11-01

    Perovskite solar cells have shown unprecedent performance increase up to 22% efficiency. However, their photovoltaic performance has shown fast deterioration under light illumination in the presence of humid air even with encapulation. The stability of perovskite materials has been unsolved and its mechanism has been elusive. Here we uncover a mechanism for irreversible degradation of perovskite materials in which trapped charges, regardless of the polarity, play a decisive role. An experimental setup using different polarity ions revealed that the moisture-induced irreversible dissociation of perovskite materials is triggered by charges trapped along grain boundaries. We also identified the synergetic effect of oxygen on the process of moisture-induced degradation. The deprotonation of organic cations by trapped charge-induced local electric field would be attributed to the initiation of irreversible decomposition.

  12. Degradation of bimorph piezoelectric bending beams in energy harvesting applications

    NASA Astrophysics Data System (ADS)

    Pillatsch, P.; Xiao, B. L.; Shashoua, N.; Gramling, H. M.; Yeatman, E. M.; Wright, P. K.

    2017-03-01

    Piezoelectric energy harvesting is an attractive alternative to battery powering for wireless sensor networks. However, in order for it to be a viable long term solution the fatigue life needs to be assessed. Many vibration harvesting devices employ bimorph piezoelectric bending beams as transduction elements to convert mechanical to electrical energy. This paper introduces two degradation studies performed under symmetrical and asymmetrical sinusoidal loading. It is shown that besides a loss in output power, the most dramatic effect of degradation is a shift in resonance frequency which is highly detrimental to resonant harvester designs. In addition, micro-cracking was shown to occur predominantly in piezoelectric layers under tensile stress. This opens the opportunity for increased life time through compressive operation or pre-loading of piezoceramic layers.

  13. Trapped charge-driven degradation of perovskite solar cells

    PubMed Central

    Ahn, Namyoung; Kwak, Kwisung; Jang, Min Seok; Yoon, Heetae; Lee, Byung Yang; Lee, Jong-Kwon; Pikhitsa, Peter V.; Byun, Junseop; Choi, Mansoo

    2016-01-01

    Perovskite solar cells have shown unprecedent performance increase up to 22% efficiency. However, their photovoltaic performance has shown fast deterioration under light illumination in the presence of humid air even with encapulation. The stability of perovskite materials has been unsolved and its mechanism has been elusive. Here we uncover a mechanism for irreversible degradation of perovskite materials in which trapped charges, regardless of the polarity, play a decisive role. An experimental setup using different polarity ions revealed that the moisture-induced irreversible dissociation of perovskite materials is triggered by charges trapped along grain boundaries. We also identified the synergetic effect of oxygen on the process of moisture-induced degradation. The deprotonation of organic cations by trapped charge-induced local electric field would be attributed to the initiation of irreversible decomposition. PMID:27830709

  14. Electric potential and electric field imaging

    NASA Astrophysics Data System (ADS)

    Generazio, E. R.

    2017-02-01

    The technology and methods for remote quantitative imaging of electrostatic potentials and electrostatic fields in and around objects and in free space is presented. Electric field imaging (EFI) technology may be applied to characterize intrinsic or existing electric potentials and electric fields, or an externally generated electrostatic field made be used for "illuminating" volumes to be inspected with EFI. The baseline sensor technology (e-Sensor) and its construction, optional electric field generation (quasi-static generator), and current e-Sensor enhancements (ephemeral e-Sensor) are discussed. Demonstrations for structural, electronic, human, and memory applications are shown. This new EFI capability is demonstrated to reveal characterization of electric charge distribution creating a new field of study embracing areas of interest including electrostatic discharge (ESD) mitigation, crime scene forensics, design and materials selection for advanced sensors, dielectric morphology of structures, tether integrity, organic molecular memory, and medical diagnostic and treatment efficacy applications such as cardiac polarization wave propagation and electromyography imaging.

  15. Methods of degrading napalm B

    DOEpatents

    Tyndall, R.L.; Vass, A.

    1995-09-12

    Methods of degrading napalm and/or trinitrotoluene involve contacting the waste with specific intra-amoebic isolates of ATCC 40908 and/or dispersants derived therefrom. Useful isolates are deposited as ATCC 77529, NAP-1 deposited as ATCC 77526 and 13 deposited as ATCC 77527.

  16. Vibrational spectroscopy of HNS degradation

    NASA Astrophysics Data System (ADS)

    Alam, M. Kathleen; Martin, Laura; Schmitt, Randal L.; Ten Eyck, Gregory A.; Welle, Eric

    2008-08-01

    Hexanitrostilbene (HNS) is a widely used explosive, due in part to its high thermal stability. Degradation of HNS is known to occur through UV, chemical exposure, and heat exposure, which can lead to reduced performance of the material. Common methods of testing for HNS degradation include wet chemical and surface area testing of the material itself, and performance testing of devices that use HNS. The commonly used chemical tests, such as volatility, conductivity and contaminant trapping provide information on contaminants rather than the chemical stability of the HNS itself. Additionally, these tests are destructive in nature. As an alternative to these methods, we have been exploring the use of vibrational spectroscopy as a means of monitoring HNS degradation non-destructively. In particular, infrared (IR) spectroscopy lends itself well to non-destructive analysis. Molecular variations in the material can be identified and compared to pure samples. The utility of IR spectroscopy was evaluated using pressed pellets of HNS exposed to DETA (diethylaminetriamine). Amines are known to degrade HNS, with the proposed product being a σ-adduct. We have followed these changes as a function of time using various IR sampling techniques including photoacoustic and attenuated total reflectance (ATR).

  17. Photothermal degradation studies of encapsulants

    NASA Technical Reports Server (NTRS)

    Liang, R. H.

    1984-01-01

    The reliability physics program at JPL is outlined. The overall objectives and approaches are given in the program. The objectives, approaches and conclusions are given for two specific parts of the programs. These two parts are mechanistic studies of photothermal degradation and performance characteristics of materials with respect to photothermal stresses.

  18. Pesticide Degradation in Thermal Foggers.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thermal foggers are used in many parts of the world for vector control. Since thermal foggers use heat to create and help propel adulticide clouds, there is reason to examine the stability of pesticides in both diesel and water-based formulations. This study examined the degradation of 5 pesticide...

  19. Degradable polyethylene: fantasy or reality.

    PubMed

    Roy, Prasun K; Hakkarainen, Minna; Varma, Indra K; Albertsson, Ann-Christine

    2011-05-15

    Plastic waste disposal is one of the serious environmental issues being tackled by our society today. Polyethylene, particularly in packaging films, has received criticism as it tends to accumulate over a period of time, leaving behind an undesirable visual footprint. Degradable polyethylene, which would enter the eco-cycle harmlessly through biodegradation would be a desirable solution to this problem. However, the "degradable polyethylene" which is presently being promoted as an environmentally friendly alternative to the nondegradable counterpart, does not seem to meet this criterion. This article reviews the state of the art on the aspect of degradability of polyethylene containing pro-oxidants, and more importantly the effect these polymers could have on the environment in the long run. On exposure to heat, light, and oxygen, these polymers disintegrate into small fragments, thereby reducing or increasing the visual presence. However, these fragments can remain in the environment for prolonged time periods. This article also outlines important questions, particularly in terms of time scale of complete degradation, environmental fate of the polymer residues, and possible accumulation of toxins, the answers to which need to be established prior to accepting these polymers as environmentally benign alternatives to their nondegradable equivalents. It appears from the existing literature that our search for biodegradable polyethylene has not yet been realized.

  20. Methods of degrading napalm B

    DOEpatents

    Tyndall, Richard L.; Vass, Arpad

    1995-01-01

    Methods of degrading napalm and/or trinitrotoluene involve contacting the waste with specific intra-amoebic isolates of ATCC 40908 and/or dispersants derived therefrom. Useful isolates include is deposited as ATCC 77529, NAP-1 deposited as ATCC 77526 and 13 deposited as ATCC 77527.

  1. The Degradation of a Nation.

    ERIC Educational Resources Information Center

    Morozova, Galina Fedorouna

    1995-01-01

    Maintains that the process of national degradation is a real danger and concern of all Russian society. Discusses environmental concerns, such as water, soil, and air pollution; falling birth rates; aging of the population; crime; and decline in moral values. Concludes that it is imperative for all citizens to stop and reverse these trends. (CFR)

  2. Assessment Of The Functionality Of A Pilot-Scale Reactor And Its Potential For Electrochemical Degradation Of Calmagite, A Sulfonated Azo-Dye

    EPA Science Inventory

    Electrochemical degradation (ECD) is a promising technology for in situ remediation of diversely contaminated environmental matrices by application of a low level electric potential gradient. This investigation, prompted by successful bench-scale ECD of trichloroethylene,...

  3. Electric field and temperature effects in irradiated MOSFETs

    NASA Astrophysics Data System (ADS)

    Silveira, M. A. G.; Santos, R. B. B.; Leite, F. G.; Araújo, N. E.; Cirne, K. H.; Melo, M. A. A.; Rallo, A.; Aguiar, Vitor. A. P.; Aguirre, F.; Macchione, E. L. A.; Added, N.; Medina, N. H.

    2016-07-01

    Electronic devices exposed to ionizing radiation exhibit degradation on their electrical characteristics, which may compromise the functionality of the device. Understanding the physical phenomena responsible for radiation damage, which may be specific to a particular technology, it is of extreme importance to develop methods for testing and recovering the devices. The aim of this work is to check the influence of thermal annealing processes and electric field applied during irradiation of Metal Oxide Semiconductor Field Effect Transistors (MOSFET) in total ionizing dose experiments analyzing the changes in the electrical parameters in these devices

  4. Polymer electrolyte membrane water electrolysis: Restraining degradation in the presence of fluctuating power

    NASA Astrophysics Data System (ADS)

    Rakousky, Christoph; Reimer, Uwe; Wippermann, Klaus; Kuhri, Susanne; Carmo, Marcelo; Lueke, Wiebke; Stolten, Detlef

    2017-02-01

    Polymer electrolyte membrane (PEM) water electrolysis generates 'green' hydrogen when conducted with electricity from renewable - but fluctuating - sources like wind or solar photovoltaic. Unfortunately, the long-term stability of the electrolyzer performance is still not fully understood under these input power profiles. In this study, we contrast the degradation behavior of our PEM water electrolysis single cells that occurs under operation with constant and intermittent power and derive preferable operating states. For this purpose, five different current density profiles are used, of which two were constant and three dynamic. Cells operated at 1 A cm-2 show no degradation. However, degradation was observed for the remaining four profiles, all of which underwent periods of high current density (2 A cm-2). Hereby, constant operation at 2 A cm-2 led to the highest degradation rate (194 μV h-1). Degradation can be greatly reduced when the cells are operated with an intermittent profile. Current density switching has a positive effect on durability, as it causes reversible parts of degradation to recover and results in a substantially reduced degradation per mole of hydrogen produced. Two general degradation phenomena were identified, a decreased anode exchange current density and an increased contact resistance at the titanium porous transport layer (Ti-PTL).

  5. Degradation of degradable starch-polyethylene plastics in a compost environment

    SciTech Connect

    Johnson, K.E.; Pometto, A.L. III; Nikolov, Z.L. )

    1993-04-01

    Degradable plastics have differing degradation rates. Three types of degradation of polyethylene in the starch-polyethylene polymers can occur: chemical degradation, photodegradation, and biological degradation. This study examines all three types of degradation in 11 commercially produced degradable starch-polyethylene bags. Different rates for chemical and photo-degradation were found within a 20 day or an 8-week period. Results indicated that both the 70[degree]C oven and HT-HH film treatments were appropriate methods to evaluate oxidative degradation. In a compost environment, oxygen tension on the surface of the film appears to be the rate-limiting component for both chemical and biological degradation. Levels of starch in all bags was similar, so the prooxidant additive was critical in promoting the oxidative degradation of polyethylene. The Fe-Mn additive displayed the best catalytic activity. This study overall confirms degradation of starch-polyethylene plastics in a natural environment. 17 refs., 6 figs., 2 tabs.

  6. Electricity and Magnetism

    NASA Astrophysics Data System (ADS)

    Glazebrook, R. T.

    2016-10-01

    1. Electrostatics: fundamental facts; 2. Electricity as a measurable quantity; 3. Measurement of electric force and potential; 4. Condensers; 5. Electrical machines; 6. Measurement of potential and electric force; 7. Magnetic attraction and repulsion; 8. Laws of magnetic force; 9. Experiments with magnets; 10. Magnetic calculations; 11. Magnetic measurements; 12. Terrestrial magnetism; 13. The electric current; 14. Relation between electromagnetic force and current; 15. Measurement of current; 16. Measurement of resistance and electromotive force; 17. Measurement of quantity of electricity, condensers; 18. Thermal activity of a current; 19. The voltaic cell (theory); 20. Electromagnetism; 21. Magnetisation of iron; 22. Electromagnetic instruments; 23. Electromagnetic induction; 24. Applications of electromagnetic induction; 25. Telegraphy and telephony; 26. Electric waves; 27. Transference of electricity through gases: corpuscles and electrons; Answers to examples; Index.

  7. Renewable Electricity Futures (Presentation)

    SciTech Connect

    Hand, M. M.

    2012-09-01

    This presentation summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050.

  8. Renewable Electricity Futures (Presentation)

    SciTech Connect

    Mai, T.

    2012-11-01

    This presentation summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050.

  9. Renewable Electricity Futures (Presentation)

    SciTech Connect

    Mai, T.

    2012-10-01

    This presentation library summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050.

  10. Electrical Burns: First Aid

    MedlinePlus

    ... be caused by a number of sources of electricity, such as lightning, stun guns and contact with ... person who has been injured by contact with electricity should be seen by a doctor. Sometimes an ...

  11. Renewable Electricity Futures (Presentation)

    SciTech Connect

    Mai, T.

    2013-04-01

    This presentation summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050.

  12. Photovoltaic lifetime and degradation science statistical pathway development: acrylic degradation

    NASA Astrophysics Data System (ADS)

    Bruckman, Laura S.; Wheeler, Nicholas R.; Kidd, Ian V.; Sun, Jiayang; French, Roger H.

    2013-09-01

    In order to optimize and extend the life of photovoltaics (PV) modules, scienti c and mechanistic statistical analytics must be performed on a large sample of materials, components and systems. Statistically signi - cant relationships were investigated between di erent mechanistically based variables to develop a statistical pathway diagram for the degradation of acrylic that is important in concentrating photovoltaics. The statisti- cally signi cant relationships were investigated using lifetime and degradation science using a domain knowledge semi-supervised generalized structural equation modeling (semi-gSEM. Predictive analytics and prognostics are informed from the statistical pathway diagram in order to predictively understand the lifetime of PV modules in di erent stress conditions and help with these critical lifetime technologies.

  13. Effect of Electron Shading on Gate Oxide Degradation

    NASA Astrophysics Data System (ADS)

    Sakamori, Shigenori; Maruyama, Takahiro; Fujiwara, Nobuo; Miyatake, Hiroshi

    1998-04-01

    The oxide degradation due to edge and electron shading effects is investigated in a pulse-modulated plasma using metal-oxide-silicon (MOS) and metal-nitride-oxide-silicon (MNOS) capacitors. Reduction of edge defect, shading defect and electron shading charge build-up is strongly dependent on the on-time in pulse plasma. In particular, when the on-time is shorter than 50 µs, the coefficient of the shading defect becomes almost zero. The investigation of MNOS capacitors, which have the patterns with or without the substrate contact antenna, indicates that the electric stress direction applied to gate oxide changes as the device structure changes.

  14. Electric Field Imaging Project

    NASA Technical Reports Server (NTRS)

    Wilcutt, Terrence; Hughitt, Brian; Burke, Eric; Generazio, Edward

    2016-01-01

    NDE historically has focused technology development in propagating wave phenomena with little attention to the field of electrostatics and emanating electric fields. This work is intended to bring electrostatic imaging to the forefront of new inspection technologies, and new technologies in general. The specific goals are to specify the electric potential and electric field including the electric field spatial components emanating from, to, and throughout volumes containing objects or in free space.

  15. Electric arc saw apparatus

    DOEpatents

    Deichelbohrer, P.R.

    1983-08-08

    A portable, hand-held electric arc saw apparatus comprising a small frame for supporting an electrically conducting rotary blade which serves as an electrode for generating an electric arc between the blade and a workpiece of opposite polarity. Electrically conducting means are provided on said frame for transmitting current to said blade. A pair of freely movable endless belts in the form of crawler treads are employed to facilitate movement of the apparatus relative to the workpiece.

  16. Degradation of monomethylhydrazine by two soil bacteria

    SciTech Connect

    Ou, L.T.

    1988-12-01

    It has been reported that three heterotrophic soil bacteria had the capacity to degrade hydrazine. One of these organisms, Achromobacter sp., degraded hydrazine to N/sub 2/ gas. Furthermore, it was reported that monomethylhydrazine (MMH) in Arredondo fine sand was mineralized to CO/sub 2/, and that such degradation is microbial. However, microorganisms that degrade MMH have not been reported. MMH and hydrazine are chemically similar to one another. Therefore, this study was initiated to test the capacity of the two hydrazine-degrading bacteria, Achromobacter sp. and Pseudomonas sp., to degrade MMH.

  17. Electric Vehicle Technician

    ERIC Educational Resources Information Center

    Moore, Pam

    2011-01-01

    With President Obama's goal to have one million electric vehicles (EV) on the road by 2015, the electric vehicle technician should have a promising and busy future. "The job force in the car industry is ramping up for a revitalized green car industry," according to Greencareersguide.com. An electric vehicle technician will safely troubleshoot and…

  18. Electricity Serves Our Community.

    ERIC Educational Resources Information Center

    Rakow, Steven J., Ed.

    1992-01-01

    Features a color poster entitled "Electricity Serves Our Community" and describes how the poster can be used to help teach about energy, electricity concepts, and types of electrical generation. Explains how teachers can obtain other resources such as posters, lesson plans, and kits from the National Energy Foundation. (PR)

  19. Electric Current Solves Mazes

    ERIC Educational Resources Information Center

    Ayrinhac, Simon

    2014-01-01

    We present in this work a demonstration of the maze-solving problem with electricity. Electric current flowing in a maze as a printed circuit produces Joule heating and the right way is instantaneously revealed with infrared thermal imaging. The basic properties of electric current can be discussed in this context, with this challenging question:…

  20. ELECTRICAL PROPERTIES OF FOODS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Foods, especially liquid foods, conduct electricity. Unlike in metals, the charge carriers in foods are ions, instead of electrons. Under normal applications, ions carry the charges as the mass of ions moves along the electrical field. The concentration and mobility of ions determine the electrical ...

  1. Electricity demand curtailment planning

    SciTech Connect

    Allentuck, J; Carroll, O; Schnader, M

    1980-01-01

    The state of electricity demand curtailment planning for long term electricity supply disruptions is reviewed. Legal, institutional and technological problems associated with demand curtailment plans are examined, and the existence of well defined social objectives on the part of planners is questioned. A linear programming approach to electricity demand curtailment planning is presented.

  2. Qualité des eaux de la station de traitement de la ville de Skikda, Algérie Essais d'optimisation de la clarification

    NASA Astrophysics Data System (ADS)

    Meghzili, B.; Medjram, M. S.; Achour, S.

    2005-05-01

    A cause de la sécheresse qui a sévit durant une décennie, la station de traitement de l'eau potable de la ville de Skikda Algérie, en vue de combler le déficit en eau, utilise un mélange des eaux de surface (barrage) et des eaux souterraines (forage). Les résultats des analyses physico-chimiques de ces eaux montrent la présence de micropolluants, notamment le mercure, avec une concentration de 0.035 mg/l pour les eaux de surface et une concentration de 0.02 mg/l pour les eaux souterraines. Ces résultats obtenus, montrent également que la concentration en matières organiques dépasse, pour les deux sources, les normes OMS. Afin de réduire les effets de cette pollution, nous avons calculé les doses nécessaires des différents réactifs utilisés sur la base des essais d'optimisation réalisés en laboratoire. Les résultats obtenus nous ont permis de conclure que les doses de 30 à 60 mg/l de sulfate d'aluminium (S.A) sont nécessaires à une bonne élimination de la turbidité et des matières organiques (M.O) et que l'utilisation du charbon active en poudre (C.A.P) permet la réduction de la teneur en mercure au dessous du seuil admissible. L'utilisation d'un adjuvant (chaux vive) permet d'améliorer les résultats surtout pour la turbidité (4 mg/l). Une préchloration au break point semble intéressante pour améliorer la phase de floculation.

  3. Le mélanome malin: une tumeur rare des fosses nasales - à propos d'une série de 10 cas

    PubMed Central

    Errachdi, Amal; Epala, Brice Nkoua; Asabbane, Amal; Kabbali, Naoual; Hemmich, Mariem; Kebdani, Tayeb; Benjaafar, Noureddine

    2014-01-01

    Le mélanome malin des fosses nasales est une tumeur rare mais très agressive, de traitement complexe et de pronostic défavorable. Son traitement relève en principe d'une prise en charge essentiellement chirurgicale complétée par une radiothérapie. L'objectif de ce travail est de rapporter les caractéristiques cliniques, thérapeutiques et évolutives des mélanomes des fosses nasales. Nous avons analysé rétrospectivement 10 cas de mélanomes des fosses nasales suivis à l'institut national d'oncologie de Rabat. La rhinoscopie avec biopsie a permis la confirmation histologique du diagnostic de mélanome. Le bilan d'extension comprenait une tomodensitométrie ou imagerie par résonnance magnétique du massif facial, une radiographie thoracique et une échographie abdominale. Dans notre série, l’âge médian était de 67.5 ans, avec une prédominance féminine (7femmes et 3hommes). Le délai médian de découverte était de 6 mois. Deux patients étaient métastatiques d'emblée, et toutes les tumeurs étaient localement avancées au moment du diagnostic. Sept patients ont été opérés avec des limites chirurgicales envahies dans 2 cas et 3 patients étaient inopérables. 2 patients ont été irradiés après la chirurgie et 2 patients ont reçu une chimiothérapie arrêtée au moment de la progression. Deux patients ont récidivé après traitement, et un patient était en mauvais état général et a bénéficié uniquement de soins palliatifs. Tous les patients sont décédés avec un délai médian de survie de 12 mois. Le mélanome malin muqueux des fosses nasales, bien que rare, demeure une pathologie de pronostic défavorable et pose des problèmes de prise en charge. PMID:25404963

  4. Development of electric motor cycle technologies in Taiwan

    NASA Astrophysics Data System (ADS)

    Liu, C. T.; Kuo, C. C.; Pan, J. S.; Lin, B. M.

    1994-02-01

    The development of an electric motor cycle was initiated at the Industrial Technology Research Institute in 1990. Several types of experimental electric scooters have been developed and field-tested, but their individual performances are far from satisfactory. Thus, it has been decided to make improvements on both the key components (such as battery, motor and driver) and the structural designs. The targeted electric motor cycle will adopt well to city-driving conditions and will help to alleviate urban air-pollution problems. The impact of electric motor cycles on the improvement of urban air-pollution problem has been evaluated. It is found that if 20% of the total motor cycle population is replaced by electric versions, a tremendous improvement in air quality will result, but this will still not meet the air-regulation standard. At least a 50% replacement is required to prevent continuous degradation of air quality.

  5. Steam generator degradation: Current mitigation strategies for controlling corrosion

    SciTech Connect

    Millett, P.

    1997-02-01

    Steam Generator degradation has caused substantial losses of power generation, resulted in large repair and maintenance costs, and contributed to significant personnel radiation exposures in Pressurized Water Reactors (PWRs) operating throughout the world. EPRI has just published the revised Steam Generator Reference Book, which reviews all of the major forms of SG degradation. This paper discusses the types of SG degradation that have been experienced with emphasis on the mitigation strategies that have been developed and implemented in the field. SG degradation is presented from a world wide perspective as all countries operating PWRs have been effected to one degree or another. The paper is written from a US. perspective where the utility industry is currently undergoing tremendous change as a result of deregulation of the electricity marketplace. Competitive pressures are causing utilities to strive to reduce Operations and Maintenance (O&M) and capital costs. SG corrosion is a major contributor to the O&M costs of PWR plants, and therefore US utilities are evaluating and implementing the most cost effective solutions to their corrosion problems. Mitigation strategies developed over the past few years reflect a trend towards plant specific solutions to SG corrosion problems. Since SG degradation is in most cases an economic problem and not a safety problem, utilities can focus their mitigation strategies on their unique financial situation. Accordingly, the focus of R&D has shifted from the development of more expensive, prescriptive solutions (e.g. reduced impurity limits) to corrosion problems to providing the utilities with a number of cost effective mitigation options (e.g. molar ratio control, boric acid treatment).

  6. Fungal degradation of organophosphorous insecticides

    SciTech Connect

    Bumpus, J.A. ); Kakar, S.N.; Coleman, R.D. )

    1992-01-01

    Organophosphorous insecticides are used extensively to treat a variety of pests and insects. Although as a group they are easily degraded by bacteria in the environment, a number of them have half-lives of several months. Little is known about their biodegradation by fungi. We have shown that Phanerochaete chrysosporium can substantially degrade chlorpyrifos, fonofos, and terbufos (27.5%, 12.2%, and 26.6%, respectively) during 18-day incubation in nitrogen-limited stationary cultures. The results demonstrate that the clorinated pyridinyl ring of chlorpyrifos and the phenyl ring of fonofos undergo ring cleavage during biodegradation by the fungus. The usefulness of the fungus system for bioremediation is discussed. 16 refs., 7 figs., 2 tabs.

  7. Fungal degradation of organophosphorous insecticides

    SciTech Connect

    Bumpus, J.A.; Kakar, S.N.; Coleman, R.D.

    1992-07-01

    Organophosphorous insecticides are used extensively to treat a variety of pests and insects. Although as a group they are easily degraded by bacteria in the environment, a number of them have half-lives of several months. Little is known about their biodegradation by fungi. We have shown that Phanerochaete chrysosporium can substantially degrade chlorpyrifos, fonofos, and terbufos (27.5%, 12.2%, and 26.6%, respectively) during 18-day incubation in nitrogen-limited stationary cultures. The results demonstrate that the clorinated pyridinyl ring of chlorpyrifos and the phenyl ring of fonofos undergo ring cleavage during biodegradation by the fungus. The usefulness of the fungus system for bioremediation is discussed. 16 refs., 7 figs., 2 tabs.

  8. Spatial degradation of satellite data

    NASA Technical Reports Server (NTRS)

    Justice, C. O.; Markham, B. L.; Townshend, J. R. G.; Kennard, R. L.

    1989-01-01

    Consideration is given to a technique for spatially degrading high-resolution satellite data to produce comparable data sets over a range of coarser resolutions. Landsat MSS data is used to produce seven spatial resolution data sets by applying a spatial filter designed to simulate sensor response. Also, spatial degradation of coarse resolution data to provide data compression for the production of global-scale data sets is examined. NOAA AVHRR Global Area Coverage data is compared to other sampling procedures. It is found that sampling procedures that incorporate averaging result in decreased variance, while sampling procedures adopting single-value selection have higher variances and produce data values comparable with those from the original data.

  9. Electric car arrives - again

    SciTech Connect

    Dunn, S.

    1997-03-01

    The first mass-produced electric cars in modern times are here, although they are expensive, limited in capability and unfamiliar to most prospective consumers. This article presents a brief history of the reintroduction of the modern electric car as well as discussions of the limitations of development, alternative routes to both producing and selling electric cars or some modified version of electric cars, economic incentives and governmental policies, and finally a snapshot description of the future for electric cars. 6 refs., 1 tab.

  10. Non-invasive monitoring of the degradation of organic contaminants: A laboratory investigation

    NASA Astrophysics Data System (ADS)

    Fernandez, Perrine M.; Bloem, Esther; Philippe, Romain; Binley, Andrew; French, Helen K.

    2016-04-01

    Degradation of organic chemicals under various fluid saturation conditions is a process highly relevant to the protection of groundwater quality. Redox potential drives the degradation of organic compounds; its variation affects the water chemistry, gas release and also the geo-electrical signature. This study explores how non-invasive measurements sensitive to geo-electrical properties provides quantitative information about the in-situ redox conditions. Our laboratory experiment focuses on the degradation of de-icing chemicals commonly used, for example, in Norwegian airports. The experiment was conducted in a number of (1.0x0.5x0.4 m) sand boxes. Two ends of each box was contaminated with propylene glycol, an aircraft deicing fluid. Each source was placed near the water table under static hydraulic conditions. At one side of the tank, a conductor linking the contamination zone, near the water table and the unsaturated zone with a low water content, was placed to improve the degradation by facilitating the electron exchange. At the other side, degradation occurred under natural conditions. Each box was equipped with 288 electrodes, distributed on six faces to perform 3D resistivity measurements. In addition, self-potential measurements were taken from electrodes on the sand surface. Four observation wells were installed above and below the water table to provide more information on the degradation processes. Moreover, measurements of carbon dioxide on the surface were performed as higher concentrations were expected where the pollutant degraded. We would like to present and discuss a selection of the preliminary results of 3D electrical resistivity and self-potential techniques from our laboratory setup.

  11. Mechanisms of Military Coatings Degradation

    DTIC Science & Technology

    2003-08-01

    series of reactions this results in carboxylic acid and urethane group as the end products of the degradation. Both the destruction of the urethane... reaction that, ultimately, created poor adhesion and film properties. SEM micrographs and small spot XPS mapping showed the presence of intermetallic... reactions nucleating at these sites. The result was a complete loss of corrosion protection at certain locations of the substrate. The dynamics of

  12. Degradation of Nitroguanidine in Soils

    DTIC Science & Technology

    1985-01-01

    addition, air stripping for the ammonia produced could be considered. Final treatment of process waters could be accomplished with land application...CLASSIFICATION OF THIS PAGE (When Data Entered) 4 hese results indicate that land applied process water laden with nitroguanidine can be successfully treated... process , otherwise the nitroguanidine will not degrade and will leach directly into groundwaters. Preliminary work with guanidine nitrate showed this

  13. Monitoring cables for local degradation

    SciTech Connect

    Bustard, L.D.; Sliter, G.E.

    1989-01-01

    Recent experiences in operating nuclear plants in the United States have demonstrated the need for an in situ cable condition monitoring technique that can assess whether installed, low-voltage, unshielded cables have local damage that could compromise their ability to function under normal and accident service conditions. This paper summarizes current US programs that have been initiated to develop a technological basis for monitoring cables with local degradation. 7 refs.

  14. Soil Degradation: A North American perspective

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil can be degraded through erosion and formation of undesirable physical, chemical, or biological properties due to industrialization or use of inappropriate farming practices that supersede natural regeneration. Soil degradation reflects unsustainable resource management that is global in scope a...

  15. PEM Degradation Investigation Final Technical Report

    SciTech Connect

    Dan Stevenson; Lee H Spangler

    2010-10-18

    This project conducted fundamental studies of PEM MEA degradation. Insights gained from these studies were disseminated to assist MEA manufacturers in understanding degradation mechanisms and work towards DOE 2010 fuel cell durability targets.

  16. O-atom degradation mechanisms of materials

    NASA Technical Reports Server (NTRS)

    Coulter, Daniel R.; Liang, Ranty H.; Chung, Shirley Y.; Smith, Keri Oda; Gupta, Amitava

    1987-01-01

    The low Earth orbit environment is described and the critical issues relating to oxygen atom degradation are discussed. Some analytic techniques for studying the problem and preliminary results on the underlying degradation mechanisms are presented.

  17. Electrical Equipment of Electrical Stations and Substations,

    DTIC Science & Technology

    1979-10-25

    possibility of the conversion of industry on the new, more advanced energy base . Thre-e-phasp current proved to be technically and economically more... energy up to large distances it was difficultly make as a result of the large heat losses in conduits/manifolds, then heat and power plants were...transmitted by the wires of smaller sections. Decrease energy losses in electric system. Since electric generators and receivers are constructed to the

  18. Methods for degrading lignocellulosic materials

    DOEpatents

    Vlasenko, Elena; Cherry, Joel; Xu, Feng

    2008-04-08

    The present invention relates to methods for degrading a lignocellulosic material, comprising: treating the lignocellulosic material with an effective amount of one or more cellulolytic enzymes in the presence of at least one surfactant selected from the group consisting of a secondary alcohol ethoxylate, fatty alcohol ethoxylate, nonylphenol ethoxylate, tridecyl ethoxylate, and polyoxyethylene ether, wherein the presence of the surfactant increases the degradation of lignocellulosic material compared to the absence of the surfactant. The present invention also relates to methods for producing an organic substance, comprising: (a) saccharifying a lignocellulosic material with an effective amount of one or more cellulolytic enzymes in the presence of at least one surfactant selected from the group consisting of a secondary alcohol ethoxylate, fatty alcohol ethoxylate, nonylphenol ethoxylate, tridecyl ethoxylate, and polyoxyethylene ether, wherein the presence of the surfactant increases the degradation of lignocellulosic material compared to the absence of the surfactant; (b) fermenting the saccharified lignocellulosic material of step (a) with one or more fermentating microoganisms; and (c) recovering the organic substance from the fermentation.

  19. Methods for degrading lignocellulosic materials

    DOEpatents

    Vlasenko, Elena; Cherry, Joel; Xu, Feng

    2011-05-17

    The present invention relates to methods for degrading a lignocellulosic material, comprising: treating the lignocellulosic material with an effective amount of one or more cellulolytic enzymes in the presence of at least one surfactant selected from the group consisting of a secondary alcohol ethoxylate, fatty alcohol ethoxylate, nonylphenol ethoxylate, tridecyl ethoxylate, and polyoxyethylene ether, wherein the presence of the surfactant increases the degradation of lignocellulosic material compared to the absence of the surfactant. The present invention also relates to methods for producing an organic substance, comprising: (a) saccharifying a lignocellulosic material with an effective amount of one or more cellulolytic enzymes in the presence of at least one surfactant selected from the group consisting of a secondary alcohol ethoxylate, fatty alcohol ethoxylate, nonylphenol ethoxylate, tridecyl ethoxylate, and polyoxyethylene ether, wherein the presence of the surfactant increases the degradation of lignocellulosic material compared to the absence of the surfactant; (b) fermenting the saccharified lignocellulosic material of step (a) with one or more fermenting microorganisms; and (c) recovering the organic substance from the fermentation.

  20. Permeation impact on metallization degradation

    NASA Astrophysics Data System (ADS)

    Peike, C.; Hoffmann, S.; Hülsmann, P.; Weiß, K.-A.; Koehl, M.; Bentz, P.

    2012-10-01

    The degradation of the inorganic components in a PV module is, besides polymer degradation, one of the most important aspects of PV module aging. Especially the corrosion of the cell metallization may lead to significant decreases in PV module performance. But in which way the metallization corrosion is affected by the permeation of atmospheric gases is not understood, yet. In order to investigate this permeation impact, laminates with a systematic variation of back-sheet and encapsulation materials as well as different laminate set-ups were made. Two different kinds of encapsulation (EVA and PVB) and four different back-sheet materials (TAPT, PA and two different TPT foils) were used. Standard cells with a two and three bus bar set-up were used. The laminates were subjected to damp-heat aging tests with a relative humidity of 80% at 80°C and 90°C, respectively. The degradation was investigated by means of electroluminescence imaging, Raman spectroscopy and microscopy. Special attention was paid to the spatial distribution of corrosion effects on the cell. Furthermore, the occurrence of a typical damp-heat induced damage, apparent as a shaded area in the electroluminescence images, should be investigated. A corrosion of the grid and the ribbons could be observed. EDX measurements revealed the grid corrosion to go along with the formation of needles of lead compounds from the silver paste.

  1. Primary degradation of antidiabetic drugs.

    PubMed

    Markiewicz, Marta; Jungnickel, Christian; Stolte, Stefan; Białk-Bielińska, Anna; Kumirska, Jolanta; Mrozik, Wojciech

    2017-02-15

    Type 2 diabetes is a chronic disease affecting a large portion of the world population and is treated by orally administered drugs. Since these drugs are often taken in high doses and are excreted unchanged or partially metabolised many of them are nowadays detected in surface waters or wastewater treatment plants effluents. Unmetabolised antidiabetics or some of their transformation products retain their pharmacological activity, therefore their presence in the environment is highly undesired. One of the main routes of elimination from wastewaters or surface waters is biodegradation. Within this work we tested primary biodegradation of: metformin and its metabolite guanylurea, acarbose, glibenclamide, gliclazide and glimepiride. We also inspected what might be the extent of the degradation by examining the products formed during the degradation using liquid chromatography coupled to tandem mass spectrometry. Transformation of diabetes staple drug metformin to dead-end product guanylurea was generally confirmed. An alternative, though rather minor pathway leading to complete mineralisation was also found. Complete primary degradation was observed for acarbose, glibenclamide and glimepiride whereas gliclazide was shown to be resistant to biodegradation. These results allow a preliminary assessment of environmental persistency of a very important group of pharmaceuticals and show need for implementing monitoring programs.

  2. Economics of electricity

    NASA Astrophysics Data System (ADS)

    Erdmann, G.

    2015-08-01

    The following text is an introduction into the economic theory of electricity supply and demand. The basic approach of economics has to reflect the physical peculiarities of electric power that is based on the directed movement of electrons from the minus pole to the plus pole of a voltage source. The regular grid supply of electricity is characterized by a largely constant frequency and voltage. Thus, from a physical point of view electricity is a homogeneous product. But from an economic point of view, electricity is not homogeneous. Wholesale electricity prices show significant fluctuations over time and between regions, because this product is not storable (in relevant quantities) and there may be bottlenecks in the transmission and distribution grids. The associated non-homogeneity is the starting point of the economic analysis of electricity markets.

  3. Plant electrical memory.

    PubMed

    Volkov, Alexander G; Carrell, Holly; Adesina, Tejumade; Markin, Vladislav S; Jovanov, Emil

    2008-07-01

    Electrical signaling, short-term memory and rapid closure of the carnivorous plant Dionaea muscipula Ellis (Venus flytrap) have been attracting the attention of researchers since the XIX century. We found that the electrical stimulus between a midrib and a lobe closes the Venus flytrap upper leaf without mechanical stimulation of trigger hairs. The closing time of Venus flytrap by electrical stimulation is the same as mechanically induced closing. Transmission of a single electrical charge between a lobe and the midrib causes closure of the trap and induces an electrical signal propagating between both lobes and midrib. The Venus flytrap can accumulate small subthreshold charges, and when the threshold value is reached, the trap closes. Repeated application of smaller charges demonstrates the summation of stimuli. The cumulative character of electrical stimuli points to the existence of short-term electrical memory in the Venus flytrap.

  4. Simultaneous degradation of toxic refractory organic pesticide and bioelectricity generation using a soil microbial fuel cell.

    PubMed

    Cao, Xian; Song, Hai-liang; Yu, Chun-yan; Li, Xian-ning

    2015-01-01

    In this study, the soil microbial fuel cells (MFCs) were constructed in the topsoil contaminated with toxic refractory organic pesticide, hexachlorobenzene (HCB). The performance of electricity generation and HCB degradation in the soil-MFCs were investigated. The HCB degradation pathway was analyzed based on the determination of degradation products and intermediates. Experimental results showed that the HCB removal efficiencies in the three groups (soil MFCs group, open circuit control group and no adding anaerobic sludge blank group) were 71.15%, 52.49% and 38.92%, respectively. The highest detected power density was 77.5 mW/m(2) at the external resistance of 1000 Ω. HCB was degraded via the reductive dechlorination pathway in the soil MFC under anaerobic condition. The existence of the anode promoted electrogenic bacteria to provide more electrons to increase the metabolic reactions rates of anaerobic bacteria was the main way which could promote the removal efficiencies of HCB in soil MFC.

  5. Effective degradation of organic water pollutants by atmospheric non-thermal plasma torch and analysis of degradation process.

    PubMed

    Bansode, Avinash S; More, Supriya E; Siddiqui, Ejaz Ahmad; Satpute, Shruti; Ahmad, Absar; Bhoraskar, Sudha V; Mathe, Vikas L

    2017-01-01

    The paper reports the use of atmospheric non-thermal plasma torch as a catalyst for degradation of various organic pollutants dissolved in water. A flow of He mixed with air was used to produce the dielectric barrier discharge (DBD), at the tip of the torch, using pulsed electric excitation at 12 kV. The torch, operated at a power of 750 mW/mm(2), was seen to completely degrade the aqueous solutions of the pollutants namely methylene blue (MB), methyl orange (MO) and rhodamine-B (RB), at around 10(-4) M concentrations, the concentration of polluants is one order higher than of routinely used heterogeneous photocatalytic reactions, within 10 min of irradiation time at room temperature. UV Visible spectra of the organic dye molecules, monitored after different intervals of plasma-irradiation, ranging between 1 and 10 min, have been used as tools to quantify their sequential degradation. Further, instead of using He, only air was used to form plasma plume and used for degradation of organic dye which follow similar trend as that of He plasma. Further, Liquid Chromatography Mass Spectroscopy (LCMS) technique has been used to understand degradation pathway of methylene blue (MB) as a representative case. Total organic carbon (TOC) measurements indicates significant decrease in its content as a function of duration of plasma exposure onto methylene blue as a representative case. Toxicity studies were carried out onto Gram negative Escherichia coli. This indicated that methylene blue, without plasma treatment, shows growth inhibition, whereas with plasma treatment no inhibition was observed.

  6. Flow accelerated organic coating degradation

    NASA Astrophysics Data System (ADS)

    Zhou, Qixin

    Applying organic coatings is a common and the most cost effective way to protect metallic objects and structures from corrosion. Water entry into coating-metal interface is usually the main cause for the deterioration of organic coatings, which leads to coating delamination and underfilm corrosion. Recently, flowing fluids over sample surface have received attention due to their capability to accelerate material degradation. A plethora of works has focused on the flow induced metal corrosion, while few studies have investigated the flow accelerated organic coating degradation. Flowing fluids above coating surface affect corrosion by enhancing the water transport and abrading the surface due to fluid shear. Hence, it is of great importance to understand the influence of flowing fluids on the degradation of corrosion protective organic coatings. In this study, a pigmented marine coating and several clear coatings were exposed to the laminar flow and stationary immersion. The laminar flow was pressure driven and confined in a flow channel. A 3.5 wt% sodium chloride solution and pure water was employed as the working fluid with a variety of flow rates. The corrosion protective properties of organic coatings were monitored inline by Electrochemical Impedance Spectroscopy (EIS) measurement. Equivalent circuit models were employed to interpret the EIS spectra. The time evolution of coating resistance and capacitance obtained from the model was studied to demonstrate the coating degradation. Thickness, gloss, and other topography characterizations were conducted to facilitate the assessment of the corrosion. The working fluids were characterized by Fourier Transform Infrared Spectrometer (FTIR) and conductivity measurement. The influence of flow rate, fluid shear, fluid composition, and other effects in the coating degradation were investigated. We conclude that flowing fluid on the coating surface accelerates the transport of water, oxygen, and ions into the coating, as

  7. Degradation Modeling of Polyurea Pavement Markings

    DTIC Science & Technology

    2011-03-01

    DEGRADATION MODELING OF POLYUREA PAVEMENT MARKINGS THESIS Jonathan D. Needham, Captain, USAF AFIT/GEM/ENV/11-M05 DEPARTMENT OF THE...DEGRADATION MODELING OF POLYUREA PAVEMENT MARKINGS THESIS Presented to the Faculty Department of Engineering Management Graduates School of...DEGRADATION MODELING OF POLYUREA PAVEMENT MARKINGS Jonathan D. Needham, BS Captain, USAF Approved

  8. Applications and extensions of degradation modeling

    SciTech Connect

    Hsu, F.; Subudhi, M.; Samanta, P.K. ); Vesely, W.E. )

    1991-01-01

    Component degradation modeling being developed to understand the aging process can have many applications with potential advantages. Previous work has focused on developing the basic concepts and mathematical development of a simple degradation model. Using this simple model, times of degradations and failures occurrences were analyzed for standby components to detect indications of aging and to infer the effectiveness of maintenance in preventing age-related degradations from transforming to failures. Degradation modeling approaches can have broader applications in aging studies and in this paper, we discuss some of the extensions and applications of degradation modeling. The application and extension of degradation modeling approaches, presented in this paper, cover two aspects: (1) application to a continuously operating component, and (2) extension of the approach to analyze degradation-failure rate relationship. The application of the modeling approach to a continuously operating component (namely, air compressors) shows the usefulness of this approach in studying aging effects and the role of maintenance in this type component. In this case, aging effects in air compressors are demonstrated by the increase in both the degradation and failure rate and the faster increase in the failure rate compared to the degradation rate shows the ineffectiveness of the existing maintenance practices. Degradation-failure rate relationship was analyzed using data from residual heat removal system pumps. A simple linear model with a time-lag between these two parameters was studied. The application in this case showed a time-lag of 2 years for degradations to affect failure occurrences. 2 refs.

  9. Applications and extensions of degradation modeling

    SciTech Connect

    Hsu, F.; Subudhi, M.; Samanta, P.K.; Vesely, W.E.

    1991-12-31

    Component degradation modeling being developed to understand the aging process can have many applications with potential advantages. Previous work has focused on developing the basic concepts and mathematical development of a simple degradation model. Using this simple model, times of degradations and failures occurrences were analyzed for standby components to detect indications of aging and to infer the effectiveness of maintenance in preventing age-related degradations from transforming to failures. Degradation modeling approaches can have broader applications in aging studies and in this paper, we discuss some of the extensions and applications of degradation modeling. The application and extension of degradation modeling approaches, presented in this paper, cover two aspects: (1) application to a continuously operating component, and (2) extension of the approach to analyze degradation-failure rate relationship. The application of the modeling approach to a continuously operating component (namely, air compressors) shows the usefulness of this approach in studying aging effects and the role of maintenance in this type component. In this case, aging effects in air compressors are demonstrated by the increase in both the degradation and failure rate and the faster increase in the failure rate compared to the degradation rate shows the ineffectiveness of the existing maintenance practices. Degradation-failure rate relationship was analyzed using data from residual heat removal system pumps. A simple linear model with a time-lag between these two parameters was studied. The application in this case showed a time-lag of 2 years for degradations to affect failure occurrences. 2 refs.

  10. Amended Electric Field Distribution: A Reliable Technique for Electrical Performance Improvement in Nano scale SOI MOSFETs

    NASA Astrophysics Data System (ADS)

    Ramezani, Zeinab; Orouji, Ali A.

    2017-04-01

    To achieve reliable transistors, we propose a new silicon-on-insulator (SOI) metal-oxide-semiconductor field-effect transistor (MOSFET) with an amended electric field in the channel for improved electrical and thermal performance, with an emphasis on current leakage improvement. The amended electric field leads to lower electric field crowding and thereby we assume enhanced reliability, leakage current, gate-induced drain leakage (GIDL), and electron temperature. To modify the electric field distribution, an additional rectangular metal region (RMR) is utilized in the buried oxide of the SOI MOSFET. The location and dimensions of the RMR have been carefully optimized to achieve the best results. The electrical, thermal, and radiofrequency characteristics of the proposed structure were analyzed using two-dimensional (2-D) numerical simulations and compared with the characteristics of the conventional, fully depleted SOI MOSFET (C-SOI). Also, critical short-channel effects (SCEs) such as threshold voltage, drain-induced barrier lowering (DIBL), subthreshold slope degradation, hot-carrier effect, GIDL, and leakage power consumption are improved. According to the results obtained, the proposed nano SOI MOSFET is a reliable device, especially for use in low-power and high-temperature applications.

  11. An Elementary Treatise on Electricity

    NASA Astrophysics Data System (ADS)

    Clerk Maxwell, James; Garnett, William

    2011-06-01

    Editor's preface; Fragment of author's preface; 1. Experiment 1; 2. On the charges of electrified bodies; 3. On electrical work and energy; 4. The electric field; 5. Faraday's law of lines of induction; 6. Particular cases of electrification; 7. Electrical images; 8. Capacity; 9. Electric current; 10. Phenomena of an electric current which flows through heterogeneous media; 11. Methods of maintaining an electric current; 12. On the measurement of electric resistance; 13. On the electric resistance of substances.

  12. Electricity Market Module - NEMS Documentation

    EIA Publications

    2014-01-01

    Documents the Electricity Market Module as it was used for the Annual Energy Outlook 2013. The Electricity Market Module (EMM) is the electricity supply component of the National Energy Modeling System (NEMS). The EMM represents the generation, transmission, and pricing of electricity. It consists of four submodules: the Electricity Capacity Planning (ECP) Submodule, the Electricity Fuel Dispatch (EFD) Submodule, the Electricity Finance and Pricing (EFP) Submodule, and the Electricity Load and Demand (ELD) Submodule.

  13. Forced degradation study of thiocolchicoside: characterization of its degradation products.

    PubMed

    Erika, Del Grosso; Silvio, Aprile; Giorgio, Grosa

    2012-03-05

    Thiocolchicoside (TCC, N-[1,2-dimethoxy-10-methylsulphanyl-9-oxo-3-(3,4,5-trihydroxy-6-hydroxymethyl-tetrahydropyran-2-yloxy)-5,6,7,9-tetrahydro-benzo[a]heptalen-7-yl]-acetamide) was subjected to hydrolytic, oxidative, and photolytic stresses. TCC underwent degradation in acidic, basic, and oxidative conditions, while it was stable toward other stress conditions. The degradation products (DPs) were detected and their separation was achieved on a SGE Wakosil C18RS 5μm (250*4.6 mm; SGE) column employing a gradient LC-MS method for a total time of analysis of 18 min. The mass fragmentation pathways of both thiocolchicoside and its degradation products were established using LC-MS experiments assigning the structures to the DPs. In particular, five DPs were identified as: D1SO (N-[1,2-dimethoxy-10-methylsulphoxide-9-oxo-3-(3,4,5-trihydroxy-6-hydroxymethyl-tetrahydropyran-2-yloxy)-5,6,7,9-tetrahydro-benzo[a]heptalen-7-yl]-acetamide), D1SO(2) (N-[1,2-dimethoxy-10-methylsulphone-9-oxo-3-(3,4,5-trihydroxy-6-hydroxymethyl-tetrahydropyran-2-yloxy)-5,6,7,9-tetrahydro-benzo[a]heptalen-7-yl]-acetamide), D2 ([1,2-dimethoxy-10-methylsulphanyl-9-oxo-3-(3,4,5-trihydroxy-6-hydroxymethyl-tetrahydropyran-2-yloxy)-5,6,7,9-tetrahydro-benzo[a]heptalen-7-yl]-amine), D3 (N-[1,2-dimethoxy-3-hydroxy-10-methylsulphanyl-9-oxo-5,6,7,9-tetrahydro-benzo[a]heptalen-7-yl]-acetamide or 3-O-demethylthiocolchicine), D4 ([1,2-dimethoxy-3-hydroxy-10-methylsulphanyl-9-oxo-5,6,7,9-tetrahydro-benzo[a]heptalen-7-yl]-amine or N-deacetyl-3-O-demethylthiocochicine). Moreover, the structures of DPs were confirmed by synthesis of the reference standards which were fully characterized by MS, NMR, IR analyses. Finally a comprehensive degradation scheme of TCC was proposed allowing to outline D1SO and D3 as the indicators of its stability for oxidative and hydrolytic stress conditions.

  14. Recognition of temporally interrupted and spectrally degraded sentences with additional unprocessed low-frequency speech

    PubMed Central

    Başkent, Deniz; Chatterjee, Monita

    2010-01-01

    Recognition of periodically interrupted sentences (with an interruption rate of 1.5 Hz, 50% duty cycle) was investigated under conditions of spectral degradation, implemented with a noiseband vocoder, with and without additional unprocessed low-pass filtered speech (cutoff frequency 500 Hz). Intelligibility of interrupted speech decreased with increasing spectral degradation. For all spectral-degradation conditions, however, adding the unprocessed low-pass filtered speech enhanced the intelligibility. The improvement at 4 and 8 channels was higher than the improvement at 16 and 32 channels: 19% and 8%, on average, respectively. The Articulation Index predicted an improvement of 0.09, in a scale from 0 to 1. Thus, the improvement at poorest spectral-degradation conditions was larger than what would be expected from additional speech information. Therefore, the results implied that the fine temporal cues from the unprocessed low-frequency speech, such as the additional voice pitch cues, helped perceptual integration of temporally interrupted and spectrally degraded speech, especially when the spectral degradations were severe. Considering the vocoder processing as a cochlear-implant simulation, where implant users’ performance is closest to 4 and 8-channel vocoder performance, the results support additional benefit of low-frequency acoustic input in combined electric-acoustic stimulation for perception of temporally degraded speech. PMID:20817081

  15. [Degradation of antipyrin by pyrazon-degrading bacteria (author's transl)].

    PubMed

    Sauber, K; Müller, R; Keller, E; Eberspächer, J; Lingens, F

    1977-01-01

    Bacteria with the ability to grow on pyrazon as sole source of carbon were isolated from soil. They also are able to grow on antipyrin. Then three metabolites of antipyrin can be isolated from the culture fluid which were identified as 2,3-dimethyl-1-(cis-2,3-dihydro-2,3-dihydroxy-4,6-cyclohexadiene-1-yl)-pyrazolone (5) (I), as 2,3-dimethyl-1-(2,3-dihydroxyphenyl)-pyrazolone (5) (II) and as 2,3-dimethyl-pyrazolone (5) (III), respectively. Compound I and II were used as substrates for enzyme studies. A dioxygenase catalyzes the enzymatic conversion of antipyrin into compound I. In the presence of NAD as cosubstrate compound I is transformed into compound II by a dehydrogenase. A pure preparation of metapyrocatechase from pyrazon-degrading bacteria converts compound II into the dephenylated heterocyclic moiety of antipyrin (III) and into 2-pyrone-6-carboxylic acid. Based on the results of the enzymatic studies a pathway for the degradation of antipyrin is proposed.

  16. Step-Stress Accelerated Degradation Testing for Solar Reflectors: Preprint

    SciTech Connect

    Jones, W.; Elmore, R.; Lee, J.; Kennedy, C.

    2011-09-01

    To meet the challenge to reduce the cost of electricity generated with concentrating solar power (CSP) new low-cost reflector materials are being developed including metalized polymer reflectors and must be tested and validated against appropriate failure mechanisms. We explore the application of testing methods and statistical inference techniques for quantifying estimates and improving lifetimes of concentrating solar power (CSP) reflectors associated with failure mechanisms initiated by exposure to the ultraviolet (UV) part of the solar spectrum. In general, a suite of durability and reliability tests are available for testing a variety of failure mechanisms where the results of a set are required to understand overall lifetime of a CSP reflector. We will focus on the use of the Ultra-Accelerated Weathering System (UAWS) as a testing device for assessing various degradation patterns attributable to accelerated UV exposure. Depending on number of samples, test conditions, degradation and failure patterns, test results may be used to derive insight into failure mechanisms, associated physical parameters, lifetimes and uncertainties. In the most complicated case warranting advanced planning and statistical inference, step-stress accelerated degradation (SSADT) methods may be applied.

  17. Factors Affecting Degradation of Aldicarb and Ethoprop

    PubMed Central

    Jones, Russell L.; Norris, Frank A.

    1998-01-01

    Chemical and microbial degradation of the nematicides-insecticides aldicarb and ethoprop has been studied extensively in both laboratory and field studies. These studies show that temperature is the most important variable affecting the degradation rate of aldicarb and its carbamate metabolites in surface soils. Temperature and organic matter appear to be the most important variables affecting degradation rates of ethoprop in soils under normal agricultural conditions, with organic matter being inversely related to degradation, presumably due to increased binding to soil particles. Soil moisture may be important under some conditions for both compounds, with degradation reduced in low-moisture soils. The rate of degradation of aldicarb residues (aldicarb + aldicarb sulfoxide + aldicarb sulfone) does not seem to be significantly affected by depth from soil surface, except that aldicarb residues degrade more slowly in acidic, coarse sand subsoils. Degradation of ethoprop also continues in subsurface soils, although field data are limited due to its lower mobility. Both compounds degrade in groundwater. Because microbial activity decreases with depth below soil surface, chemical processes are important components of the degradation of both aldicarb residues and ethoprop. For aldicarb, transformation to carbamate oxides in surface soils is primarily microbial, while degradation to noncarbamate compounds appears to be primarily the result of soil-catalyzed hydrolysis throughout the soil profile. For ethoprop, both chemical and microbial catalyzed hydrolysis are important in surface soils, with chemical hydrolysis becoming more important with increasing depth. PMID:19274198

  18. Integrated electrical connector

    DOEpatents

    Benett, William J.; Ackler, Harold D.

    2005-05-24

    An electrical connector is formed from a sheet of electrically conductive material that lies in between the two layers of nonconducting material that comprise the casing of an electrical chip. The connector is electrically connected to an electrical element embedded within the chip. An opening in the sheet is concentrically aligned with a pair of larger holes respectively bored through the nonconducting layers. The opening is also smaller than the diameter of an electrically conductive contact pin. However, the sheet is composed flexible material so that the opening adapts to the diameter of the pin when the pin is inserted therethrough. The periphery of the opening applies force to the sides of the pin when the pin is inserted, and thus holds the pin within the opening and in contact with the sheet, by friction. The pin can be withdrawn from the connector by applying sufficient axial force.

  19. Electrical system architecture

    DOEpatents

    Algrain, Marcelo C.; Johnson, Kris W.; Akasam, Sivaprasad; Hoff, Brian D.

    2008-07-15

    An electrical system for a vehicle includes a first power source generating a first voltage level, the first power source being in electrical communication with a first bus. A second power source generates a second voltage level greater than the first voltage level, the second power source being in electrical communication with a second bus. A starter generator may be configured to provide power to at least one of the first bus and the second bus, and at least one additional power source may be configured to provide power to at least one of the first bus and the second bus. The electrical system also includes at least one power consumer in electrical communication with the first bus and at least one power consumer in electrical communication with the second bus.

  20. Thermoacoustic magnetohydrodynamic electrical generator

    DOEpatents

    Wheatley, John C.; Swift, Gregory W.; Migliori, Albert

    1986-01-01

    A thermoacoustic magnetohydrodynamic electrical generator includes an intrinsically irreversible thermoacoustic heat engine coupled to a magnetohydrodynamic electrical generator. The heat engine includes an electrically conductive liquid metal as the working fluid and includes two heat exchange and thermoacoustic structure assemblies which drive the liquid in a push-pull arrangement to cause the liquid metal to oscillate at a resonant acoustic frequency on the order of 1,000 Hz. The engine is positioned in the field of a magnet and is oriented such that the liquid metal oscillates in a direction orthogonal to the field of the magnet, whereby an alternating electrical potential is generated in the liquid metal. Low-loss, low-inductance electrical conductors electrically connected to opposite sides of the liquid metal conduct an output signal to a transformer adapted to convert the low-voltage, high-current output signal to a more usable higher voltage, lower current signal.

  1. Thermoacoustic magnetohydrodynamic electrical generator

    DOEpatents

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1984-11-16

    A thermoacoustic magnetohydrodynamic electrical generator includes an intrinsically irreversible thermoacoustic heat engine coupled to a magnetohydrodynamic electrical generator. The heat engine includes an electrically conductive liquid metal as the working fluid and includes two heat exchange and thermoacoustic structure assemblies which drive the liquid in a push-pull arrangement to cause the liquid metal to oscillate at a resonant acoustic frequency on the order of 1000 Hz. The engine is positioned in the field of a magnet and is oriented such that the liquid metal oscillates in a direction orthogonal to the field of the magnet, whereby an alternating electrical potential is generated in the liquid metal. Low-loss, low-inductance electrical conductors electrically connected to opposite sides of the liquid metal conduct an output signal to a transformer adapted to convert the low-voltage, high-current output signal to a more usable higher voltage, lower current signal.

  2. Electric power monthly

    SciTech Connect

    1995-08-01

    The Energy Information Administration (EIA) prepares the Electric Power Monthly (EPM) for a wide audience including Congress, Federal and State agencies, the electric utility industry, and the general public. This publication provides monthly statistics for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fossil fuels are also displayed for the North American Electric Reliability Council (NERC) regions. The EIA publishes statistics in the EPM on net generation by energy source, consumption, stocks, quantity, quality, and cost of fossil fuels; and capability of new generating units by company and plant. The purpose of this publication is to provide energy decisionmakers with accurate and timely information that may be used in forming various perspectives on electric issues that lie ahead.

  3. Enzymatic degradation of polycaprolactone-gelatin blend

    NASA Astrophysics Data System (ADS)

    Banerjee, Aditi; Chatterjee, Kaushik; Madras, Giridhar

    2015-04-01

    Blends of polycaprolactone (PCL), a synthetic polymer and gelatin, natural polymer offer a optimal combination of strength, water wettability and cytocompatibility for use as a resorbable biomaterial. The enzymatic degradation of PCL, gelatin and PCL-gelatin blended films was studied in the presence of lipase (Novozym 435, immobilized) and lysozyme. Novozym 435 degraded the PCL films whereas lysozyme degraded the gelatin. Though Novozym 435 and lysozyme individually could degrade PCL-gelatin blended films, the combination of these enzymes showed the highest degradation of these blended films. Moreover, the enzymatic degradation was much faster when fresh enzymes were added at regular intervals. The changes in physico-chemical properties of polymer films due to degradation were studied by scanning electron microscopy, Fourier transform infrared spectroscopy and differential scanning calorimetry. These results have important implications for designing resorbable biomedical implants.

  4. Isolation and characterization of fenamiphos degrading bacteria.

    PubMed

    Cabrera, J Alfonso; Kurtz, Andreas; Sikora, Richard A; Schouten, Alexander

    2010-11-01

    The biological factors responsible for the microbial breakdown of the organophosphorus nematicide fenamiphos were investigated. Microorganisms responsible for the enhanced degradation of fenamiphos were isolated from soil that had a long application history of this nematicide. Bacteria proved to be the most important group of microbes responsible for the fenamiphos biodegradation process. Seventeen bacterial isolates utilized the pure active ingredient fenamiphos as a carbon source. Sixteen isolates rapidly degraded the active ingredient in Nemacur 5GR. Most of the fenamiphos degrading bacteria were Microbacterium species, although Sinorhizobium, Brevundimonas, Ralstonia and Cupriavidus were also identified. This array of gram positive and gram negative fenamiphos degrading bacteria appeared to be pesticide-specific, since cross-degradation toward fosthiazate, another organophosphorus pesticide used for nematode control, did not occur. It was established that the phylogenetical relationship among nematicide degrading bacteria is closer than that to non-degrading isolates.

  5. Protease-degradable electrospun fibrous hydrogels

    NASA Astrophysics Data System (ADS)

    Wade, Ryan J.; Bassin, Ethan J.; Rodell, Christopher B.; Burdick, Jason A.

    2015-03-01

    Electrospun nanofibres are promising in biomedical applications to replicate features of the natural extracellular matrix (ECM). However, nearly all electrospun scaffolds are either non-degradable or degrade hydrolytically, whereas natural ECM degrades proteolytically, often through matrix metalloproteinases. Here we synthesize reactive macromers that contain protease-cleavable and fluorescent peptides and are able to form both isotropic hydrogels and electrospun fibrous hydrogels through a photoinitiated polymerization. These biomimetic scaffolds are susceptible to protease-mediated cleavage in vitro in a protease dose-dependent manner and in vivo in a subcutaneous mouse model using transdermal fluorescent imaging to monitor degradation. Importantly, materials containing an alternate and non-protease-cleavable peptide sequence are stable in both in vitro and in vivo settings. To illustrate the specificity in degradation, scaffolds with mixed fibre populations support selective fibre degradation based on individual fibre degradability. Overall, this represents a novel biomimetic approach to generate protease-sensitive fibrous scaffolds for biomedical applications.

  6. Serological studies on chloridazon-degrading bacteria.

    PubMed

    Layh, G; Böhm, R; Eberspächer, J; Lingens, F

    1983-01-01

    Agglutination tests and immunofluorescence tests with antisera against four strains of chloridazon-degrading bacteria revealed the serological uniformity of a group of 22 chloridazon-degrading bacterial strains. No serological relationship could be found between chloridazon-degrading bacteria and representatives of other Gram-negative bacteria. This was demonstrated by agglutination tests, including testing of the antiserum against Acinetobacter calcoaceticus, and by immunofluorescence tests, including testing of the sera against Pseudomonas and Acinetobacter strains. The tests were performed with 31 representatives of different Gram-negative bacteria, and with 22 strains of chloridazon-degrading bacteria as antigens. Differences in the extent of agglutination reactions and antibody titres among chloridazon-degrading bacterial strains together with cross-adsorption xperiments, suggest a rough classification of chloridazon-degrading bacteria into two subgroups. On the basis of immunofluorescence data, a linkage-map was worked out to represent serological relationships in the group of chloridazon-degrading strains.

  7. STRUCTURAL PERFORMANCE OF DEGRADED REINFORCED CONCRETE MEMBERS.

    SciTech Connect

    Braverman, J.I.; Miller, C.A.; Ellingwood, B.R.; Naus, D.J.; Hofmayer, C.H.; Bezler, P.; Chang, T.Y.

    2001-03-22

    This paper describes the results of a study to evaluate, in probabilistic terms, the effects of age-related degradation on the structural performance of reinforced concrete members at nuclear power plants. The paper focuses on degradation of reinforced concrete flexural members and shear walls due to the loss of steel reinforcing area and loss of concrete area (cracking/spalling). Loss of steel area is typically caused by corrosion while cracking and spalling can be caused by corrosion of reinforcing steel, freeze-thaw, or aggressive chemical attack. Structural performance in the presence of uncertainties is depicted by a fragility (or conditional probability of failure). The effects of degradation on the fragility of reinforced concrete members are calculated to assess the potential significance of various levels of degradation. The fragility modeling procedures applied to degraded concrete members can be used to assess the effects of degradation on plant risk and can lead to the development of probability-based degradation acceptance limits.

  8. Degradation of Victoria Crater, Mars

    NASA Technical Reports Server (NTRS)

    Wilson, Sharon A.; Grant, John A.; Cohen, Barbara A.; Golombek, Mathew P.; Geissler, Paul E.; Sullivan, Robert J.; Kirk, Randolph L.; Parker, Timothy J.

    2008-01-01

    The $\\sim$750 m diameter and $\\sim$75 m deep Victoria crater in Meridiani Planum, Mars, presents evidence for significant degradation including a low, serrated, raised rim characterized by alternating alcoves and promontories, a surrounding low relief annulus, and a floor partially covered by dunes. The amount and processes of degradation responsible for the modified appearance of Victoria crater were evaluated using images obtained in situ by the Mars Exploration Rover Opportunity in concert with a digital elevation model created using orbital HiRISE images. Opportunity traversed along the north and northwest rim and annulus, but sufficiently characterized features visible in the DEM to enable detailed measurements of rim relief, ejecta thickness, and wall slopes around the entire degraded, primary impact structure. Victoria retains a 5 m raised rim consisting of 1-2 m of uplifted rocks overlain by 3 m of ejecta at the rim crest. The rim is $\\sim$120 to 220 m wide and is surrounded by a dark annulus reaching an average of 590 m beyond the raised rim. Comparison between observed morphology and that expected for pristine craters 500 to 750 m across indicate the original, pristine crater was close to 600 m in diameter. Hence, the crater has been erosionally widened by approximately 150 m and infilled by about 50 m of sediments. Eolian processes are responsible for modification at Victoria, but lesser contributions from mass wasting or other processes cannot be ruled out. Erosion by prevailing winds is most significant along the exposed rim and upper walls and accounts for $\\sim$50 m widening across a WNW-ESE diameter. The volume of material eroded from the crater walls and rim is $\\sim$20% less than the volume of sediments partially filling the crater, indicating eolian infilling from sources outside the crater over time. The annulus formed when $\\sim$1 m deflation of the ejecta created a lag of more resistant hematite spherules that trapped darker, regional

  9. Degradation of Victoria Crater, Mars

    NASA Astrophysics Data System (ADS)

    Wilson, S. A.; Grant, J. A.; Cohen, B. A.; Golombek, M. P.; Geissler, P. E.; Sullivan, R. J.; Kirk, R. L.; Parker, T. J.

    2008-12-01

    The approximately 750 m diameter and 75 m deep Victoria crater in Meridiani Planum, Mars, presents evidence for significant degradation including a low, serrated, raised rim characterized by alternating alcoves and promontories, a surrounding low relief annulus, and a floor partially covered by dunes. The amount and processes of degradation responsible for the modified appearance of Victoria crater were evaluated using images obtained in situ by the Mars Exploration Rover Opportunity in concert with a digital elevation model (DEM) created using orbital HiRISE images. Opportunity traversed along the north and northwest rim and annulus and sufficiently characterized features visible in the DEM, thereby enabling detailed measurements of rim relief, ejecta thickness, and wall slopes around the entire degraded, primary impact structure. Victoria retains a 5 m raised rim consisting of 1 to 2 m of uplifted rocks overlain by 3 m of ejecta at the rim crest. The rim is 120 to 220 m wide and is surrounded by a dark annulus reaching an average of 590 m beyond the raised rim. Comparison between observed morphology and that expected for pristine craters 500 to 750 m across indicate the original, pristine crater was close to 600 m in diameter. Hence, the crater has been erosionally widened by approximately 150 m and infilled by about 50 m of sediments. Eolian processes are responsible for modification at Victoria, but lesser contributions from mass wasting or other processes cannot be ruled out. Erosion by prevailing winds is most significant along the exposed rim and upper walls and accounts for roughly 50 m widening across a WNW to ESE diameter. The volume of material eroded from the crater walls and rim is about 20 percent less than the volume of sediments partially filling the crater, indicating eolian infilling from sources outside the crater over time. The annulus formed when less than 1 m deflation of the ejecta created a lag of more resistant hematite spherules that

  10. Conductivity degradation of polyvinylidene fluoride composite binder during cycling: Measurements and simulations for lithium-ion batteries

    SciTech Connect

    Grillet, Anne M.; Humplik, Thomas; Stirrup, Emily K.; Roberts, Scott A.; Barringer, David A.; Snyder, Chelsea M.; Janvrin, Madison R.; Apblett, Christopher A.

    2016-07-02

    The polymer-composite binder used in lithium-ion battery electrodes must both hold the electrodes together and augment their electrical conductivity while subjected to mechanical stresses caused by active material volume changes due to lithiation and delithiation. We have discovered that cyclic mechanical stresses cause significant degradation in the binder electrical conductivity. After just 160 mechanical cycles, the conductivity of polyvinylidene fluoride (PVDF):carbon black binder dropped between 45–75%. This degradation in binder conductivity has been shown to be quite general, occurring over a range of carbon black concentrations, with and without absorbed electrolyte solvent and for different polymer manufacturers. Mechanical cycling of lithium cobalt oxide (LiCoO2) cathodes caused a similar degradation, reducing the effective electrical conductivity by 30–40%. Mesoscale simulations on a reconstructed experimental cathode geometry predicted the binder conductivity degradation will have a proportional impact on cathode electrical conductivity, in qualitative agreement with the experimental measurements. Lastly, ohmic resistance measurements were made on complete batteries. Direct comparisons between electrochemical cycling and mechanical cycling show consistent trends in the conductivity decline. This evidence supports a new mechanism for performance decline of rechargeable lithium-ion batteries during operation – electrochemically-induced mechanical stresses that degrade binder conductivity, increasing the internal resistance of the battery with cycling.

  11. Conductivity degradation of polyvinylidene fluoride composite binder during cycling: Measurements and simulations for lithium-ion batteries

    DOE PAGES

    Grillet, Anne M.; Humplik, Thomas; Stirrup, Emily K.; ...

    2016-07-02

    The polymer-composite binder used in lithium-ion battery electrodes must both hold the electrodes together and augment their electrical conductivity while subjected to mechanical stresses caused by active material volume changes due to lithiation and delithiation. We have discovered that cyclic mechanical stresses cause significant degradation in the binder electrical conductivity. After just 160 mechanical cycles, the conductivity of polyvinylidene fluoride (PVDF):carbon black binder dropped between 45–75%. This degradation in binder conductivity has been shown to be quite general, occurring over a range of carbon black concentrations, with and without absorbed electrolyte solvent and for different polymer manufacturers. Mechanical cycling ofmore » lithium cobalt oxide (LiCoO2) cathodes caused a similar degradation, reducing the effective electrical conductivity by 30–40%. Mesoscale simulations on a reconstructed experimental cathode geometry predicted the binder conductivity degradation will have a proportional impact on cathode electrical conductivity, in qualitative agreement with the experimental measurements. Lastly, ohmic resistance measurements were made on complete batteries. Direct comparisons between electrochemical cycling and mechanical cycling show consistent trends in the conductivity decline. This evidence supports a new mechanism for performance decline of rechargeable lithium-ion batteries during operation – electrochemically-induced mechanical stresses that degrade binder conductivity, increasing the internal resistance of the battery with cycling.« less

  12. The earth's electrical environment

    SciTech Connect

    Not Available

    1986-01-01

    This latest addition to the Studies in Geophysics series explores in scientific detail the phenomenon of lighting, cloud and thunderstorm electricity, and global and regional electrical processes. Consisting of 16 papers by outstanding experts in a number of fields, this volume compiles and reviews many recent advances in such research areas as meteorology, chemistry, electrical engineering, and physics and projects how new knowledge could be applied to benefit mankind.

  13. Electrical control of superparamagnetism

    NASA Astrophysics Data System (ADS)

    Yamada, Kihiro T.; Koyama, Tomohiro; Kakizakai, Haruka; Miwa, Kazumoto; Ando, Fuyuki; Ishibashi, Mio; Kim, Kab-Jin; Moriyama, Takahiro; Ono, Shimpei; Chiba, Daichi; Ono, Teruo

    2017-01-01

    The electric field control of superparamagnetism is realized using a Cu/Ni system, in which the deposited Ni shows superparamagnetic behavior above the blocking temperature. An electric double-layer capacitor (EDLC) with the Cu/Ni electrode and a nonmagnetic counter electrode is fabricated to examine the electric field effect on magnetism in the magnetic electrode. By changing the voltage applied to the EDLC, the blocking temperature of the system is clearly modulated.

  14. Essays on electricity theft

    NASA Astrophysics Data System (ADS)

    Steadman, Keva Ullanda

    Electricity theft is a relatively unknown crime with high economic costs. In this dissertation, I try to identify the factors that motivate persons to steal electricity. First, I use a panel dataset of 97 countries spanning the five year period 2003--2007 to estimate a model that describes the effect of the unemployment rate, GDP per capita, male population and urbanization on theft, robbery and homicide rates. The results are consistent with previous empirical work on crime and economic opportunity. The second and main contribution of this paper is to estimate the same model using distribution loss as a proxy for electricity theft. The results show that the unemployment rate, a key explanatory economic factor for crime, cannot explain variation in electricity theft, although there is some evidence, albeit weak, supporting correlation in rich countries. Therefore, policies that target the reduction of property crime through a reduction in unemployment will have no effect on electricity theft. The third contribution relates to the role that political institutions play in the incentives to steal electricity. After control for socioeconomic factors, I find that there is no relationship between political governance indicators and electricity theft. In the second and third chapters, I compare the United States, a high income, low electricity theft country with Jamaica, a middle income, high electricity theft country. The effect of unemployment on electricity theft mirrors the results found in the first chapter. In the United States, electricity theft is affected by changes in economic conditions but in Jamaica, it is not. These results suggest that the state of institutions plays a role in how social norms are determined. Poor countries will be more likely than rich countries to have weak institutions with social norms that encourage electricity theft.

  15. Expendable Electric Landrover (EEL)

    DTIC Science & Technology

    2004-07-01

    DAHLGREN DIVISION NAVAL SURFACE WARFARE CENTER Panama City, Florida 32407-7001 NSWC PC/MP-04/07 EXPENDABLE ELECTRIC LANDROVER (EEL) MITCH GAVRILASH...COVERED JULY 2004 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS EXPENDABLE ELECTRIC LANDROVER (EEL) 6. AUTHOR(S) MITCH GAVRILASH 7. PERFORMING ORGANIZATION NAME...generations of Expendable Electric Landrover (EEL) robots were developed during fiscal year 2003 at the Naval Surface Warfare Center, Panama City (NSWC-PC

  16. Electric Drive Study

    DTIC Science & Technology

    1987-03-01

    Track-Laying Combat Vehicles , and (3) Parametric Study of Electric Drive Component Technologies. The technology survey results are given in a separate...and projections of future electric drive system improvements relative to combat vehicle applications. Unclassified SECURITY CLASSIFICATION OF THIS...273 5.7.2.3.1 DC Homopolar Drum Machine, Design and Performance 5-278 APPENDIX A 19.5 TON AND 40.0 TON VEHICLE SPECIFICATION APPENDIX B ELECTRIC

  17. Electric vehicle's electricity consumption on a road with different slope

    NASA Astrophysics Data System (ADS)

    Yang, S. C.; Li, M.; Lin, Y.; Tang, T. Q.

    2014-05-01

    In this paper, we propose an extended car-following model and an electricity consumption model to study the effects of the road's slope on the electric vehicle's electricity consumption. The numerical results show that each electric vehicle's electricity consumption increases with the uphill's tilt angle and decreases with the downhill's tilt angle. In addition, each electric vehicle's electricity consumption increases with the uphill's (downhill's) length under a certain tilt angle.

  18. Electric power annual 1992

    SciTech Connect

    Not Available

    1994-01-06

    The Electric Power Annual presents a summary of electric utility statistics at national, regional and State levels. The objective of the publication is to provide industry decisionmakers, government policymakers, analysts and the general public with historical data that may be used in understanding US electricity markets. The Electric Power Annual is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels; Energy Information Administration (EIA); US Department of Energy. ``The US Electric Power Industry at a Glance`` section presents a profile of the electric power industry ownership and performance, and a review of key statistics for the year. Subsequent sections present data on generating capability, including proposed capability additions; net generation; fossil-fuel statistics; retail sales; revenue; financial statistics; environmental statistics; electric power transactions; demand-side management; and nonutility power producers. In addition, the appendices provide supplemental data on major disturbances and unusual occurrences in US electricity power systems. Each section contains related text and tables and refers the reader to the appropriate publication that contains more detailed data on the subject matter. Monetary values in this publication are expressed in nominal terms.

  19. Electric vehicle propulsion alternatives

    NASA Technical Reports Server (NTRS)

    Secunde, R. R.; Schuh, R. M.; Beach, R. F.

    1983-01-01

    Propulsion technology development for electric vehicles is summarized. Analytical studies, technology evaluation, and the development of technology for motors, controllers, transmissions, and complete propulsion systems are included.

  20. Electrical Circuit Tester

    DOEpatents

    Love, Frank

    2006-04-18

    An electrical circuit testing device is provided, comprising a case, a digital voltage level testing circuit with a display means, a switch to initiate measurement using the device, a non-shorting switching means for selecting pre-determined electrical wiring configurations to be tested in an outlet, a terminal block, a five-pole electrical plug mounted on the case surface and a set of adapters that can be used for various multiple-pronged electrical outlet configurations for voltages from 100 600 VAC from 50 100 Hz.

  1. Electrical Power Requirements.

    DTIC Science & Technology

    POWER SUPPLIES, TEST METHODS), ARMY EQUIPMENT, BATTERY COMPONENTS, ELECTRIC BATTERIES, VEHICLES, GENERATORS, FUEL CELLS, SEEBECK EFFECT , TEST EQUIPMENT, ELECTROMAGNETIC COMPATIBILITY, DATA PROCESSING

  2. Electrically conductive cellulose composite

    DOEpatents

    Evans, Barbara R.; O'Neill, Hugh M.; Woodward, Jonathan

    2010-05-04

    An electrically conductive cellulose composite includes a cellulose matrix and an electrically conductive carbonaceous material incorporated into the cellulose matrix. The electrical conductivity of the cellulose composite is at least 10 .mu.S/cm at 25.degree. C. The composite can be made by incorporating the electrically conductive carbonaceous material into a culture medium with a cellulose-producing organism, such as Gluconoacetobacter hansenii. The composites can be used to form electrodes, such as for use in membrane electrode assemblies for fuel cells.

  3. Perforation patterned electrical interconnects

    SciTech Connect

    Frey, Jonathan

    2014-01-28

    This disclosure describes systems and methods for increasing the usable surface area of electrical contacts within a device, such as a thin film solid state device, through the implementation of electrically conductive interconnects. Embodiments described herein include the use of a plurality of electrically conductive interconnects that penetrate through a top contact layer, through one or more multiple layers, and into a bottom contact layer. The plurality of conductive interconnects may form horizontal and vertical cross-sectional patterns. The use of lasers to form the plurality of electrically conductive interconnects from reflowed layer material further aids in the manufacturing process of a device.

  4. Early detection of materials degradation

    NASA Astrophysics Data System (ADS)

    Meyendorf, Norbert

    2017-02-01

    Lightweight components for transportation and aerospace applications are designed for an estimated lifecycle, taking expected mechanical and environmental loads into account. The main reason for catastrophic failure of components within the expected lifecycle are material inhomogeneities, like pores and inclusions as origin for fatigue cracks, that have not been detected by NDE. However, material degradation by designed or unexpected loading conditions or environmental impacts can accelerate the crack initiation or growth. Conventional NDE methods are usually able to detect cracks that are formed at the end of the degradation process, but methods for early detection of fatigue, creep, and corrosion are still a matter of research. For conventional materials ultrasonic, electromagnetic, or thermographic methods have been demonstrated as promising. Other approaches are focused to surface damage by using optical methods or characterization of the residual surface stresses that can significantly affect the creation of fatigue cracks. For conventional metallic materials, material models for nucleation and propagation of damage have been successfully applied for several years. Material microstructure/property relations are well established and the effect of loading conditions on the component life can be simulated. For advanced materials, for example carbon matrix composites or ceramic matrix composites, the processes of nucleation and propagation of damage is still not fully understood. For these materials NDE methods can not only be used for the periodic inspections, but can significantly contribute to the material scientific knowledge to understand and model the behavior of composite materials.

  5. Degradation of Methyldopa by Banana.

    PubMed

    Uesawa, Yoshihiro; Mohri, Kiminori

    2010-03-02

    Methyldopa, an antihypertensive, is a very close analogue of DOPA. Drug interaction accompanied by degradation in a banana juice mixture was reported for DOPA. However, the effect of banana on methyldopa has not been reported. Therefore, we have investigated the impact of banana juice on methyldopa. The drug and supernatant of banana pulp were mixed, and the mixture was observed for changes in color, drug concentration, and ultraviolet-visible absorption spectra at 30 °C. The originally clear and colorless mixture started to acquire a yellow coloration after about 30 seconds after the mixing. The color tone increasingly deepened, then blistered solid particles that do not dissolve were observed after 3 hours. Concentration of methyldopa in the mixture decreased by 60% after 5 min, to 0.5% after 30 min of the mixing. From these findings, it was suggested that the drastic alterations were caused by banana polyphenol oxidase that plays a role in the biosynthesis of melanin pigment from levodopa in banana pulp. Because the degradation of methyldopa occurs extremely fast, it was suggested concomitant use of this anti-hypertensive and banana juice consumption should be avoided in clinical practice.

  6. Hydrolytic Degradation of Estane 5703

    SciTech Connect

    Wrobleski, D.A.; Smith, M.E.; Orler, E.B.

    1999-04-27

    Relative to the unaged Estane{reg_sign} 5703, heating decreases the modulus and ultimate stress for both the dry and humid samples. The sample aged in dry air, quickly recovered to its original mechanical properties. The reversibility of the mechanical properties is a result of the reorganization of the hard segments into domains. For the Estane 5703 samples aged in humid air, the mechanical properties only partially recovered with time. Molecular weight data confirm that differences in the extent of the recovery for the samples aged under humid environments are likely due to the hydrolytic scission of the polyester soft segments. Since the tensile moduli are similar for the samples aged in both the dry and humid environments, it is believed that the phase behavior of the hard domains dictate the mechanical properties at low extensions. However, at higher elongations, the mechanical properties are dominated by the soft segments. Both the influences of morphological changes and chemical changes induced by heating must be considered in multiphase polymers when accelerated aging is utilized to predict long term polymer properties. After accelerated aging experiments, the morphology must be allowed to recover to equilibrium conditions in order to assess the extent of degradation and aging. Also, the effect of different humidities on the rate of hydrolytic degradation are presented.

  7. Degradation of Victoria crater, Mars

    NASA Astrophysics Data System (ADS)

    Grant, John A.; Wilson, Sharon A.; Cohen, Barbara A.; Golombek, Matthew P.; Geissler, Paul E.; Sullivan, Robert J.; Kirk, Randolph L.; Parker, Timothy J.

    2008-11-01

    The ~750 m diameter and ~75 m deep Victoria crater in Meridiani Planum, Mars, is a degraded primary impact structure retaining a ~5 m raised rim consisting of 1-2 m of uplifted rocks overlain by ~3 m of ejecta at the rim crest. The rim is 120-220 m wide and is surrounded by a dark annulus reaching an average of 590 m beyond the raised rim. Comparison between observed morphology and that expected for pristine craters 500-750 m across indicates that the original, pristine crater was close to 600 m in diameter. Hence, the crater has been erosionally widened by ~150 m and infilled by ~50 m of sediments. Eolian processes are responsible for most crater modification, but lesser mass wasting or gully activity contributions cannot be ruled out. Erosion by prevailing winds is most significant along the exposed rim and upper walls and accounts for ~50 m widening across a WNW-ESE diameter. The volume of material eroded from the crater walls and rim is ~20% less than the volume of sediments partially filling the crater, indicating eolian infilling from sources outside the crater over time. The annulus formed when ~1 m deflation of the ejecta created a lag of more resistant hematite spherules that trapped <10-20 cm of darker, regional basaltic sands. Greater relief along the rim enabled meters of erosion. Comparison between Victoria and regional craters leads to definition of a crater degradation sequence dominated by eolian erosion and infilling over time.

  8. Modelling of parasitic effects induced by electrically active defects in a SiGe HBT

    NASA Astrophysics Data System (ADS)

    Lakhdara, M.; Latreche, S.; Gontrand, C.

    2008-07-01

    In this paper, we present a numerical modelling of a NPN SiGe heterojunction bipolar transistor (HBT) realized in an industrial 0.35 μ m BiCMOS process, using our own software simulator “SIBIDIF”, taking into account some electrically active defects in the HBT device. The electric performances of this device can be penalized by the presence of defects inherent to the complex structure shrinking. For our devices, most of these relevant defects are located at the vertical interface between the spacers and the polysilicon emitter, due to the Reactive Ion Etching (RIE) process step. Nevertheless, their localization, as well as theirs effective density or their capture section, have an influence on the electric characteristics of the HBT's. As a check, we find some good agreement between our simulated results and some experimental ones. Our work is focused on the identification of defects responsible for the current fluctuations at the origin of low frequency noise or Random Telegraphic Signals in industrial submicronic BiCMOS technologies. Gummel characteristics are simulated in order to identify generation-recombination or trap assisted tunnelling process in the base current. We have shown that devices having an excess base current present random discrete fluctuations on the base current.

  9. Investigation of on-current degradation behavior induced by surface hydrolysis effect under negative gate bias stress in amorphous InGaZnO thin-film transistors

    NASA Astrophysics Data System (ADS)

    Liu, Kuan-Hsien; Chang, Ting-Chang; Chang, Kuan-Chang; Tsai, Tsung-Ming; Hsieh, Tien-Yu; Chen, Min-Chen; Yeh, Bo-Liang; Chou, Wu-Ching

    2014-03-01

    This study investigates the electrical instability under negative gate bias stress (NGBS) induced by surface hydrolysis effect. Electrical characteristics exhibit instability for amorphous InGaZnO (a-IGZO) Thin Film Transistors (TFTs) under NGBS, in which on-current degradation and current crowding phenomenon can be observed. When the negative gate bias is applied on the TFT, hydrogen ions will dissociate from ZnO-H bonds and the dissociated hydrogen ions will cause electrical instability under NGBS. The ISE-Technology Computer Aided Design simulation tool and moisture partial pressure modulation measurement are utilized to clarify the anomalous degradation behavior.

  10. Electricity market module: Electricity capacity planning submodule

    SciTech Connect

    1996-06-01

    The purpose of this report is to describe modifications to the Electricity Capacity Planning Submodule (ECP) for the Annual Energy Outlook 1996. It describes revisions to enhance the representation of planned maintenance, incorporate technological improvements in operating efficiencies, revise the algorithm for determining international firm power imports, and include risk premiums for new plant construction.

  11. SEMICONDUCTOR DEVICES: Off-state avalanche breakdown induced degradation in 20 V NLDMOS devices

    NASA Astrophysics Data System (ADS)

    Shifeng, Zhang; Koubao, Ding; Yan, Han; Chenggong, Han; Jiaxian, Hu; Bin, Zhang

    2010-09-01

    Degradation behaviors of 20 V NLDMOS operated under off-state avalanche breakdown conditions are presented. A constant current pulse stressing test is applied to the device. Two different degradation mechanisms are identified by analysis of electrical data, technology computer-aided design (TCAD) simulations and charge pumping measurements. The first mechanism is attributed to positive oxide-trapped charges in the N-type drift region, and the second one is due to decreased electron mobility upon interface state formation in the drift region. Both of the mechanisms are enhanced with increasing avalanche breakdown current.

  12. Enhanced Degradation by Negative Bias Temperature Stress in Si Nanowire Transistor

    NASA Astrophysics Data System (ADS)

    Ota, Kensuke; Saitoh, Masumi; Tanaka, Chika; Nakabayashi, Yukio; Uchida, Ken; Numata, Toshinori

    2012-02-01

    Negative bias temperature instability in Si nanowire transistors were systematically studied. Enhanced degradation by negative bias temperature (NBT) stress in narrow nanowire transistor was observed. Nanowire width and height dependences on threshold voltage shift suggest that the larger degradation was caused by the nanowire corner effect such as electric field concentration. High speed measurements elucidated the smaller recovery ratio in nanowire transistors which is attributed to be the local charge trap at nanowire corner. Stress memorization technique does not affect the threshold voltage shift by NBT stress.

  13. Energy 101: Electric Vehicles

    SciTech Connect

    2012-01-01

    This edition of Energy 101 highlights the benefits of electric vehicles, including improved fuel efficiency, reduced emissions, and lower maintenance costs. For more information on electric vehicles from the Office of Energy Efficiency and Renewable Energy, visit the Vehicle Technologies Program website: http://www1.eere.energy.gov/vehiclesandfuels/

  14. Electric Vehicle Battery Challenge

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2014-01-01

    A serious drawback to electric vehicles [batteries only] is the idle time needed to recharge their batteries. In this challenge, students can develop ideas and concepts for battery change-out at automotive service stations. Such a capability would extend the range of electric vehicles.

  15. The Theory of Electricity

    NASA Astrophysics Data System (ADS)

    Livens, G. H.

    2016-10-01

    Preface; 1. The electric field; 2. Dielectric theory; 3. Electric currents; 4. The magnetic field; 5. The dynamics of the magnetic field; 6. Maxwell's electromagnetic theory; 7. Electromagnetic oscillations and waves; 8. The electrodynamics of moving media; Appendix 1. On the mechanism of magnetic induction; Appendix 2. On the mechanism of metallic conduction; Index.

  16. Renewable Electricity Futures (Presentation)

    SciTech Connect

    Hand, M.; Mai, T.

    2012-08-01

    This presentation library summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. It was presented in an Union of Concerned Scientists webinar on June 12, 2012.

  17. Electric vehicles: Driving range

    NASA Astrophysics Data System (ADS)

    Kempton, Willett

    2016-09-01

    For uptake of electric vehicles to increase, consumers' driving-range needs must be fulfilled. Analysis of the driving patterns of personal vehicles in the US now shows that today's electric vehicles can meet all travel needs on almost 90% of days from a single overnight charge.

  18. Electric Propulsion Apparatus

    NASA Technical Reports Server (NTRS)

    Patterson, Michael J. (Inventor)

    2013-01-01

    An electric propulsion machine includes an ion thruster having an annular discharge chamber housing an anode having a large surface area. The ion thruster includes flat annular ion optics with a small span to gap ratio. Optionally, a second electric propulsion thruster may be disposed in a cylindrical space disposed within an interior of the annulus.

  19. Energy 101: Electric Vehicles

    ScienceCinema

    None

    2016-07-12

    This edition of Energy 101 highlights the benefits of electric vehicles, including improved fuel efficiency, reduced emissions, and lower maintenance costs. For more information on electric vehicles from the Office of Energy Efficiency and Renewable Energy, visit the Vehicle Technologies Program website: http://www1.eere.energy.gov/vehiclesandfuels/

  20. Aircraft Electric Secondary Power

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Technologies resulted to aircraft power systems and aircraft in which all secondary power is supplied electrically are discussed. A high-voltage dc power generating system for fighter aircraft, permanent magnet motors and generators for aircraft, lightweight transformers, and the installation of electric generators on turbine engines are among the topics discussed.

  1. Renewable Electricity Futures (Presentation)

    SciTech Connect

    Hand, M.

    2012-10-01

    This presentation library summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. It is being presented at the Utility Variable-Generation Integration Group Fall Technical Workshop on October 24, 2012.

  2. Renewable Electricity Futures (Presentation)

    SciTech Connect

    Mai, T.

    2012-08-01

    This presentation summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. This presentation was presented in a Wind Powering America webinar on August 15, 2012 and is now available through the Wind Powering America website.

  3. Renewable Electricity Futures (Presentation)

    SciTech Connect

    Mai, T.

    2012-08-01

    This presentation summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. It was presented in a Power Systems Engineering Research Center webinar on September 4, 2012.

  4. Renewable Electricity Futures (Presentation)

    SciTech Connect

    Hand, M. M.

    2012-08-01

    This presentation library summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. It was presented in a webinar given by the California Energy Commission.

  5. Multilayer flat electrical cable

    NASA Technical Reports Server (NTRS)

    Silverman, P. G.

    1973-01-01

    Flat electrical cable is lightweight, flexible over wide temperature range, withstands continuous exposure to high levels of nuclear radiation, and can carry high currents with minimum of temperature rise. Its magnetic cleanliness is equal to or better than twisted pair of wires, and it can be terminated in conventional electrical connector.

  6. Electricity and Its Use.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with the use of electricity. Its objective is for the student to be able to discuss consumer uses of electricity and understand increased usage and problems relating to needs for production expansion. Some topics covered are major…

  7. Electrically conductive diamond electrodes

    DOEpatents

    Swain, Greg; Fischer, Anne ,; Bennett, Jason; Lowe, Michael

    2009-05-19

    An electrically conductive diamond electrode and process for preparation thereof is described. The electrode comprises diamond particles coated with electrically conductive doped diamond preferably by chemical vapor deposition which are held together with a binder. The electrodes are useful for oxidation reduction in gas, such as hydrogen generation by electrolysis.

  8. Electric Power Monthly

    EIA Publications

    2017-01-01

    Provides monthly statistics at the state, Census division, and U.S. levels for net generation, fossil fuel consumption and stocks, quantity and quality of fossil fuels, cost of fossil fuels, electricity sales, revenue, and average revenue per kilowatthour of electricity sold.

  9. Efficient Use of Electricity.

    ERIC Educational Resources Information Center

    Fickett, Arnold P.; And Others

    1990-01-01

    Discussed are advanced technologies which may offer an opportunity to meet the world's future energy needs while minimizing the environmental impact. Savings to both suppliers and consumers are described. International electricity usage is compared. Government standards for the manufacture of electrical products in the United States are…

  10. Electric propulsion, circa 2000

    NASA Technical Reports Server (NTRS)

    Hudson, W. R.; Finke, R. C.

    1980-01-01

    This paper discusses the future of electric propulsion, circa 2000. Starting with the first generation Solar Electric Propulsion (SEP) technology as the first step toward the next century's advanced propulsion systems, the current status and future trends of other systems such as the magnetoplasmadynamic accelerator, the mass driver, the laser propulsion system, and the rail gun are described.

  11. Problem Solving in Electricity.

    ERIC Educational Resources Information Center

    Caillot, Michel; Chalouhi, Elias

    Two studies were conducted to describe how students perform direct current (D-C) circuit problems. It was hypothesized that problem solving in the electricity domain depends largely on good visual processing of the circuit diagram and that this processing depends on the ability to recognize when two or more electrical components are in series or…

  12. Hawaii electric system reliability.

    SciTech Connect

    Silva Monroy, Cesar Augusto; Loose, Verne William

    2012-09-01

    This report addresses Hawaii electric system reliability issues; greater emphasis is placed on short-term reliability but resource adequacy is reviewed in reference to electric consumers' views of reliability %E2%80%9Cworth%E2%80%9D and the reserve capacity required to deliver that value. The report begins with a description of the Hawaii electric system to the extent permitted by publicly available data. Electrical engineering literature in the area of electric reliability is researched and briefly reviewed. North American Electric Reliability Corporation standards and measures for generation and transmission are reviewed and identified as to their appropriateness for various portions of the electric grid and for application in Hawaii. Analysis of frequency data supplied by the State of Hawaii Public Utilities Commission is presented together with comparison and contrast of performance of each of the systems for two years, 2010 and 2011. Literature tracing the development of reliability economics is reviewed and referenced. A method is explained for integrating system cost with outage cost to determine the optimal resource adequacy given customers' views of the value contributed by reliable electric supply. The report concludes with findings and recommendations for reliability in the State of Hawaii.

  13. Hawaii Electric System Reliability

    SciTech Connect

    Loose, Verne William; Silva Monroy, Cesar Augusto

    2012-08-01

    This report addresses Hawaii electric system reliability issues; greater emphasis is placed on short-term reliability but resource adequacy is reviewed in reference to electric consumers’ views of reliability “worth” and the reserve capacity required to deliver that value. The report begins with a description of the Hawaii electric system to the extent permitted by publicly available data. Electrical engineering literature in the area of electric reliability is researched and briefly reviewed. North American Electric Reliability Corporation standards and measures for generation and transmission are reviewed and identified as to their appropriateness for various portions of the electric grid and for application in Hawaii. Analysis of frequency data supplied by the State of Hawaii Public Utilities Commission is presented together with comparison and contrast of performance of each of the systems for two years, 2010 and 2011. Literature tracing the development of reliability economics is reviewed and referenced. A method is explained for integrating system cost with outage cost to determine the optimal resource adequacy given customers’ views of the value contributed by reliable electric supply. The report concludes with findings and recommendations for reliability in the State of Hawaii.

  14. Static and Current Electricity.

    ERIC Educational Resources Information Center

    Schlenker, Richard M.; Murtha, Kathy T.

    This is a copy of the script for the electrical relationships unit in an auto-tutorial physical science course for non-science majors, offered at the University of Maine at Orono. The unit includes 15 simple experiments designed to allow the student to discover various fundamental electrical relationships. The student has the option of reading the…

  15. Electrical Circuit Simulation Code

    SciTech Connect

    Wix, Steven D.; Waters, Arlon J.; Shirley, David

    2001-08-09

    Massively-Parallel Electrical Circuit Simulation Code. CHILESPICE is a massively-arallel distributed-memory electrical circuit simulation tool that contains many enhanced radiation, time-based, and thermal features and models. Large scale electronic circuit simulation. Shared memory, parallel processing, enhance convergence. Sandia specific device models.

  16. Electrical Work in Schools.

    ERIC Educational Resources Information Center

    Ontario Dept. of Education, Toronto. School Business and Finance Branch.

    Most buildings rely on electricity for lighting, power, signals, and other communications. Electric energy is also used for heating and year-round thermal conditioning of spaces. Its ease of transmission, simple control and measurement, and relative safety make it a useful source of energy. This publication is intended to provide those persons…

  17. Atoms to Electricity.

    ERIC Educational Resources Information Center

    Department of Energy, Washington, DC.

    This booklet explains the basic technology of nuclear fission power reactors, the nuclear fuel cycle, and the role of nuclear energy as one of the domestic energy resources being developed to meet the national energy demand. Major topic areas discussed include: the role of nuclear power; the role of electricity; generating electricity with the…

  18. Basic Electricity. Part 1.

    ERIC Educational Resources Information Center

    Kilmer, Donald C.

    A primarily illustrated introduction to the basics of electricity is presented in this guide, the first of a set of four designed for the student interested in a vocation in electrical work. This guide is intended for the first-year student and provides mostly diagrams with accompanying defintions/information in three units, each covering one of…

  19. Advanced electric propulsion system concept for electric vehicles

    NASA Technical Reports Server (NTRS)

    Raynard, A. E.; Forbes, F. E.

    1979-01-01

    Seventeen propulsion system concepts for electric vehicles were compared to determine the differences in components and battery pack to achieve the basic performance level. Design tradeoffs were made for selected configurations to find the optimum component characteristics required to meet all performance goals. The anticipated performance when using nickel-zinc batteries rather than the standard lead-acid batteries was also evaluated. The two systems selected for the final conceptual design studies included a system with a flywheel energy storage unit and a basic system that did not have a flywheel. The flywheel system meets the range requirement with either lead-acid or nickel-zinc batteries and also the acceleration of zero to 89 km/hr in 15 s. The basic system can also meet the required performance with a fully charged battery, but, when the battery approaches 20 to 30 percent depth of discharge, maximum acceleration capability gradually degrades. The flywheel system has an estimated life-cycle cost of $0.041/km using lead-acid batteries. The basic system has a life-cycle cost of $0.06/km. The basic system, using batteries meeting ISOA goals, would have a life-cycle cost of $0.043/km.

  20. Study of advanced electric propulsion system concept using a flywheel for electric vehicles

    NASA Technical Reports Server (NTRS)

    Younger, F. C.; Lackner, H.

    1979-01-01

    Advanced electric propulsion system concepts with flywheels for electric vehicles are evaluated and it is predicted that advanced systems can provide considerable performance improvement over existing electric propulsion systems with little or no cost penalty. Using components specifically designed for an integrated electric propulsion system avoids the compromises that frequently lead to a loss of efficiency and to inefficient utilization of space and weight. A propulsion system using a flywheel power energy storage device can provide excellent acceleration under adverse conditions of battery degradation due either to very low temperatures or high degrees of discharge. Both electrical and mechanical means of transfer of energy to and from the flywheel appear attractive; however, development work is required to establish the safe limits of speed and energy storage for advanced flywheel designs and to achieve the optimum efficiency of energy transfer. Brushless traction motor designs using either electronic commutation schemes or dc-to-ac inverters appear to provide a practical approach to a mass producible motor, with excellent efficiency and light weight. No comparisons were made with advanced system concepts which do not incorporate a flywheel.

  1. Electric turbocompound control system

    DOEpatents

    Algrain, Marcelo C.

    2007-02-13

    Turbocompound systems can be used to affect engine operation using the energy in exhaust gas that is driving the available turbocharger. A first electrical device acts as a generator in response to turbocharger rotation. A second electrical device acts as a motor to put mechanical power into the engine, typically at the crankshaft. Apparatus, systems, steps, and methods are described to control the generator and motor operations to control the amount of power being recovered. This can control engine operation closer to desirable parameters for given engine-related operating conditions compared to actual. The electrical devices can also operate in "reverse," going between motor and generator functions. This permits the electrical device associated with the crankshaft to drive the electrical device associated with the turbocharger as a motor, overcoming deficient engine operating conditions such as associated with turbocharger lag.

  2. Electric power monthly

    SciTech Connect

    Smith, Sandra R.; Johnson, Melvin; McClevey, Kenneth; Calopedis, Stephen; Bolden, Deborah

    1992-05-01

    The Electric Power Monthly is prepared by the Survey Management Division; Office of Coal, Nuclear, Electric and Alternate Fuels, Energy Information Administration (EIA), Department of Energy. This publication provides monthly statistics at the national, Census division, and State levels for net generation, fuel consumption, fuel stocks, quantity and quality of fuel, cost of fuel, electricity sales, revenue, and average revenue per kilowatthour of electricity sold. Data on net generation, fuel consumption, fuel stocks, quantity and cost of fuel are also displayed for the North American Electric Reliability Council (NERC) regions. Additionally, statistics by company and plant are published in the EPM on capability of new plants, new generation, fuel consumption, fuel stocks, quantity and quality of fuel, and cost of fuel.

  3. The biological degradation of cellulose.

    PubMed

    Béguin, P; Aubert, J P

    1994-01-01

    Cellulolytic microorganisms play an important role in the biosphere by recycling cellulose, the most abundant carbohydrate produced by plants. Cellulose is a simple polymer, but it forms insoluble, crystalline microfibrils, which are highly resistant to enzymatic hydrolysis. All organisms known to degrade cellulose efficiently produce a battery of enzymes with different specificities, which act together in synergism. The study of cellulolytic enzymes at the molecular level has revealed some of the features that contribute to their activity. In spite of a considerable diversity, sequence comparisons show that the catalytic cores of cellulases belong to a restricted number of families. Within each family, available data suggest that the various enzymes share a common folding pattern, the same catalytic residues, and the same reaction mechanism, i.e. either single substitution with inversion of configuration or double substitution resulting in retention of the beta-configuration at the anomeric carbon. An increasing number of three-dimensional structures is becoming available for cellulases and xylanases belonging to different families, which will provide paradigms for molecular modeling of related enzymes. In addition to catalytic domains, many cellulolytic enzymes contain domains not involved in catalysis, but participating in substrate binding, multi-enzyme complex formation, or possibly attachment to the cell surface. Presumably, these domains assist in the degradation of crystalline cellulose by preventing the enzymes from being washed off from the surface of the substrate, by focusing hydrolysis on restricted areas in which the substrate is synergistically destabilized by multiple cutting events, and by facilitating recovery of the soluble degradation products by the cellulolytic organism. In most cellulolytic organisms, cellulase synthesis is repressed in the presence of easily metabolized, soluble carbon sources and induced in the presence of cellulose

  4. 3D resistivity method to monitor degradation of an organic contaminant in sand boxes

    NASA Astrophysics Data System (ADS)

    Fernandez, P. M.; Bloem, E.; Philippe, R.; French, H. K.

    2015-12-01

    Degradation of organic chemicals under various saturation conditions is a process highly relevant to protect groundwater. The redox potential drives the degradation of organic compounds. Its variation affects the water chemistry, gas release and responses of the geo-electrical signature. This study explores how non-invasive measurements sensitive to geo-electrical properties provides quantitative information about the in-situ redox situation. During this presentation, the preliminary results of a laboratory experiment to study the degradation of deicing chemicals with 3D resistivity and self-potential techniques, water samples will be shown. The experiment consists of sand boxes (1.0x0.5x0.4 m) to which both sides of each box is contaminated with propylene glycol, an aircraft deicing fluid, commonly used in Norwegian airports. Each source is placed near the water table with static conditions. At one side a conductor is placed, linking the contamination zone at the water table and the unsaturated zone with a low water content, to improve the degradation by facilitating the electron exchange. At the other side, degradation occurs under natural conditions. Each box is equipped with 288 electrodes, distributed on six faces to perform 3D resistivity measurements. In addition to the resistivity, self-potential measurements are taken from the sand surface. Six water wells are installed above and below the water table to provide more information on the degradation processes. Moreover, measurements of carbon dioxide on the surface are performed as higher concentrations are expected where the pollutant is degraded.

  5. Kinetic study and mechanism of Niclosamide degradation

    NASA Astrophysics Data System (ADS)

    Zaazaa, Hala E.; Abdelrahman, Maha M.; Ali, Nouruddin W.; Magdy, Maimana A.; Abdelkawy, M.

    2014-11-01

    A spectrophotometric kinetic study of Niclosamide alkaline degradation as a function of drug concentration, alkaline concentration and temperature has been established utilizing double divisor-ratio spectra spectrophotometric method. The developed method allowed determination of Niclosamide in presence of its alkaline degradation products; namely; 2-chloro-4-nitro aniline (DEG I) and 5-chloro salicylic acid (DEG II) with characterization of its degradation mechanism. It was found that degradation kinetic of Niclosamide followed pseudo-first order under the established experimental conditions with a degradation rate constant (k) of 0.0829 mol/h and half life (t1/2) of 8.35 h. The overall degradation rate constant as a function of the temperature under the given conditions obeyed Arrhenius equation where the activation energy was calculated to be 3.41 kcal/mol.

  6. Kinetic study and mechanism of Niclosamide degradation.

    PubMed

    Zaazaa, Hala E; Abdelrahman, Maha M; Ali, Nouruddin W; Magdy, Maimana A; Abdelkawy, M

    2014-11-11

    A spectrophotometric kinetic study of Niclosamide alkaline degradation as a function of drug concentration, alkaline concentration and temperature has been established utilizing double divisor-ratio spectra spectrophotometric method. The developed method allowed determination of Niclosamide in presence of its alkaline degradation products; namely; 2-chloro-4-nitro aniline (DEG I) and 5-chloro salicylic acid (DEG II) with characterization of its degradation mechanism. It was found that degradation kinetic of Niclosamide followed pseudo-first order under the established experimental conditions with a degradation rate constant (k) of 0.0829 mol/h and half life (t1/2) of 8.35 h. The overall degradation rate constant as a function of the temperature under the given conditions obeyed Arrhenius equation where the activation energy was calculated to be 3.41 kcal/mol.

  7. Degradation of PAHs by high frequency ultrasound.

    PubMed

    Manariotis, Ioannis D; Karapanagioti, Hrissi K; Chrysikopoulos, Constantinos V

    2011-04-01

    Polycyclic aromatic hydrocarbons (PAHs) are persistent organic compounds, which have been reported in the literature to efficiently degrade at low (e.g. 20 kHz) and moderate (e.g. 506 kHz) ultrasound frequencies. The present study focuses on degradation of naphthalene, phenanthrene, and pyrene by ultrasound at three different relatively high frequencies (i.e. 582, 862, and 1142 kHz). The experimental results indicate that for all three frequencies and power inputs ≥ 133 W phenanthrene degrades to concentrations lower than our experimental detection limit (<1 μg/L). Phenanthrene degrades significantly faster at 582 kHz than at 862 and 1142 kHz. For all three frequencies, the degradation rates per unit mass are similar for naphthalene and phenanthrene and lower for pyrene. Furthermore, naphthalene degradation requires less energy than phenanthrene, which requires less energy than pyrene under the same conditions. No hexane-extractable metabolites were identified in the solutions.

  8. Thermal degradation of cereal straws in air

    SciTech Connect

    Ghaly, A.E. )

    1990-01-01

    This paper reports the thermogravimetric behavior of four cereal straws (wheat, barley, oats, and rye) at three heating rates (10, 20, and 50{degrees}C/min) in air examined. The thermal degradation rate, the initial degradation temperature, the active and passive pyrolysis zones, and the residual weight at 600{degrees}C were determined. Increasing the heating rate increased the thermal degradation rate and decreased both the initial degradation temperature and the residual weight at 600{degrees}C. The higher the cellulosic content of the straw, the higher the thermal degradation rate and the initial degradation temperature. Also, higher ash content in the straw resulted in higher residual weight at 600{degrees}C.

  9. Microbial degradation of pyridine using Pseudomonas sp. and isolation of plasmid responsible for degradation.

    PubMed

    Mohan, S Venkata; Sistla, Srinivas; Guru, R Kumar; Prasad, K Krishna; Kumar, C Suresh; Ramakrishna, S V; Sarma, P N

    2003-01-01

    Pseudomonas (PI2) capable of degrading pyridine was isolated from the mixed population of the activated sludge unit which was being used for treating complex effluents, the strain was characterized. Aerobic degradation of pyridine was studied with the isolated strain and the growth parameters were evaluated. Pyridine degradation was further conformed by chromatography (HPLC) analysis. The process parameters like biomass growth and dissolved oxygen consumption were monitored during pyridine degradation. In order to conform with the plasmid capability to degrade pyridine, the requisite plasmid was isolated and transferred to DH 5alpha Escherichia coli. The subsequent biodegradation studies revealed the ability of the transformed plasmid capability to degrade the pyridine.

  10. Bacterial Degradation of Aromatic Compounds

    PubMed Central

    Seo, Jong-Su; Keum, Young-Soo; Li, Qing X.

    2009-01-01

    Aromatic compounds are among the most prevalent and persistent pollutants in the environment. Petroleum-contaminated soil and sediment commonly contain a mixture of polycyclic aromatic hydrocarbons (PAHs) and heterocyclic aromatics. Aromatics derived from industrial activities often have functional groups such as alkyls, halogens and nitro groups. Biodegradation is a major mechanism of removal of organic pollutants from a contaminated site. This review focuses on bacterial degradation pathways of selected aromatic compounds. Catabolic pathways of naphthalene, fluorene, phenanthrene, fluoranthene, pyrene, and benzo[a]pyrene are described in detail. Bacterial catabolism of the heterocycles dibenzofuran, carbazole, dibenzothiophene, and dibenzodioxin is discussed. Bacterial catabolism of alkylated PAHs is summarized, followed by a brief discussion of proteomics and metabolomics as powerful tools for elucidation of biodegradation mechanisms. PMID:19440284

  11. Microbial degradation of petroleum hydrocarbons.

    PubMed

    Varjani, Sunita J

    2017-01-01

    Petroleum hydrocarbon pollutants are recalcitrant compounds and are classified as priority pollutants. Cleaning up of these pollutants from environment is a real world problem. Bioremediation has become a major method employed in restoration of petroleum hydrocarbon polluted environments that makes use of natural microbial biodegradation activity. Petroleum hydrocarbons utilizing microorganisms are ubiquitously distributed in environment. They naturally biodegrade pollutants and thereby remove them from the environment. Removal of petroleum hydrocarbon pollutants from environment by applying oleophilic microorganisms (individual isolate/consortium of microorganisms) is ecofriendly and economic. Microbial biodegradation of petroleum hydrocarbon pollutants employs the enzyme catalytic activities of microorganisms to enhance the rate of pollutants degradation. This article provides an overview about bioremediation for petroleum hydrocarbon pollutants. It also includes explanation about hydrocarbon metabolism in microorganisms with a special focus on new insights obtained during past couple of years.

  12. Degradation of Endeavour Crater, Mars

    NASA Technical Reports Server (NTRS)

    Grant, J. A.; Crumpler, L. S.; Parker, T. J.; Golombek, M. P.; Wilson, S. A.; Mittlefehldt, D. W.

    2015-01-01

    The Opportunity rover has traversed portions of two western rim segments of Endeavour, a 22 km-diameter crater in Meridiani Planum, for the past three years. The resultant data enables the evaluation of the geologic expression and degradation state of the crater. Endeavour is Noa-chian-aged, complex in morphology, and originally may have appeared broadly similar to the more pristine 20.5 km-diameter Santa Fe complex crater in Lunae Palus (19.5degN, 312.0degE). By contrast, Endeavour is considerably subdued and largely buried by younger sulfate-rich plains. Exposed rim segments dubbed Cape York (CY) and Solander Point/Murray Ridge/Pillinger Point (MR) located approximately1500 m to the south reveal breccias interpreted as remnants of the ejecta deposit, dubbed the Shoemaker Formation. At CY, the Shoemaker Formation overlies the pre-impact rocks, dubbed the Matijevic Formation.

  13. Durability Improvements Through Degradation Mechanism Studies

    SciTech Connect

    Borup, Rodney L.; Mukundan, Rangachary; Spernjak, Dusan; Baker, Andrew M.; Lujan, Roger W.; Langlois, David Alan; Ahluwalia, Rajesh; Papadia, D. D.; Weber, Adam Z.; Kusoglu, Ahmet; Shi, Shouwnen; More, K. L.; Grot, Steve

    2015-08-03

    The durability of polymer electrolyte membrane (PEM) fuel cells is a major barrier to the commercialization of these systems for stationary and transportation power applications. By investigating cell component degradation modes and defining the fundamental degradation mechanisms of components and component interactions, new materials can be designed to improve durability. To achieve a deeper understanding of PEM fuel cell durability and component degradation mechanisms, we utilize a multi-institutional and multi-disciplinary team with significant experience investigating these phenomena.

  14. Degradation of Victoria crater, Mars

    USGS Publications Warehouse

    Grant, J. A.; Wilson, S.A.; Cohen, B. A.; Golombek, M.P.; Geissler, P.E.; Sullivan, R.J.; Kirk, R.L.; Parker, T.J.

    2008-01-01

    The ???750 m diameter and ???75 m deep Victoria crater in Meridiani Planum, Mars, is a degraded primary impact structure retaining a ???5 m raised rim consisting of 1-2 m of uplifted rocks overlain by ???3 m of ejecta at the rim crest. The rim is 120-220 m wide and is surrounded by a dark annulus reaching an average of 590 m beyond the raised rim. Comparison between observed morphology and that expected for pristine craters 500-750 m across indicates that the original, pristine crater was close to 600 m in diameter. Hence, the crater has been erosionally widened by ???150 m and infilled by ???50 m of sediments. Eolian processes are responsible for most crater modification, but lesser mass wasting or gully activity contributions cannot be ruled out. Erosion by prevailing winds is most significant along the exposed rim and upper walls and accounts for ???50 m widening across a WNW-ESE diameter. The volume of material eroded from the crater walls and rim is ???20% less than the volume of sediments partially filling the crater, indicating eolian infilling from sources outside the crater over time. The annulus formed when ???1 m deflation of the ejecta created a lag of more resistant hematite spherules that trapped <10-20 cm of darker, regional basaltic sands. Greater relief along the rim enabled meters of erosion. Comparison between Victoria and regional craters leads to definition of a crater degradation sequence dominated by eolian erosion and infilling over time. Copyright 2008 by the American Geophysical Union.

  15. CLAD DEGRADATION - FEPS SCREENING ARGUMENTS

    SciTech Connect

    R. Schreiner

    2004-10-21

    The purpose of this report is to evaluate and document the screening of the clad degradation features, events, and processes (FEPs) with respect to modeling used to support the Total System Performance Assessment-License Application (TSPA-LA). This report also addresses the effect of certain FEPs on both the cladding and the commercial spent nuclear fuel (CSNF), DOE-owned spent nuclear fuel (DSNF), and defense high-level waste (DHLW) waste forms, as appropriate to address the effects on multiple materials and both components (FEPs 2.1.09.09.0A, 2.1.09.11.0A, 2.1.11.05.0A, 2.1.12.02.0A, and 2.1.12.03.0A). These FEPs are expected to affect the repository performance during the postclosure regulatory period of 10,000 years after permanent closure. Table 1-1 provides the list of cladding FEPs, including their screening decisions (include or exclude). The primary purpose of this report is to identify and document the analysis, screening decision, and TSPA-LA disposition (for included FEPs) or screening argument (for excluded FEPs) for these FEPs related to clad degradation. In some cases, where a FEP covers multiple technical areas and is shared with other FEP reports, this report may provide only a partial technical basis for the screening of the FEP. The full technical basis for shared FEPs is addressed collectively by the sharing FEP reports. The screening decisions and associated TSPA-LA dispositions or screening arguments from all of the FEP reports are cataloged in a project-specific FEPs database.

  16. Electrical efficiency and droop in MQW LEDs

    NASA Astrophysics Data System (ADS)

    Malyutenko, V. K.

    2014-02-01

    It is believed that low power conversion efficiency in commercial MQW LEDs occurs as a result of efficiency droop, current-induced dynamic degradation of the internal quantum efficiency, injection efficiency, and extraction efficiency. Broadly speaking, all these "quenching" mechanisms could be referred to as the optical losses. The vast advances of high-power InGaN and AlGaInP MQW LEDs have been achieved by addressing these losses. In contrast to these studies, in this paper we consider an alternative approach to make high-power LEDs more efficient. We identify current-induced electrical efficiency degradation (EED) as a strong limiting factor of power conversion efficiency. We found that EED is caused by current crowding followed by an increase in current-induced series resistance of a device. By decreasing the current spreading length, EED also causes the optical efficiency to degrade and stands for an important aspect of LED performance. This paper gives scientists the opportunity to look for different attributes of EED.

  17. On-Orbit Degradation of Solar Instruments

    NASA Astrophysics Data System (ADS)

    BenMoussa, A.; Gissot, S.; Schühle, U.; Del Zanna, G.; Auchère, F.; Mekaoui, S.; Jones, A. R.; Walton, D.; Eyles, C. J.; Thuillier, G.; Seaton, D.; Dammasch, I. E.; Cessateur, G.; Meftah, M.; Andretta, V.; Berghmans, D.; Bewsher, D.; Bolsée, D.; Bradley, L.; Brown, D. S.; Chamberlin, P. C.; Dewitte, S.; Didkovsky, L. V.; Dominique, M.; Eparvier, F. G.; Foujols, T.; Gillotay, D.; Giordanengo, B.; Halain, J. P.; Hock, R. A.; Irbah, A.; Jeppesen, C.; Judge, D. L.; Kretzschmar, M.; McMullin, D. R.; Nicula, B.; Schmutz, W.; Ucker, G.; Wieman, S.; Woodraska, D.; Woods, T. N.

    2013-11-01

    We present the lessons learned about the degradation observed in several space solar missions, based on contributions at the Workshop about On-Orbit Degradation of Solar and Space Weather Instruments that took place at the Solar Terrestrial Centre of Excellence (Royal Observatory of Belgium) in Brussels on 3 May 2012. The aim of this workshop was to open discussions related to the degradation observed in Sun-observing instruments exposed to the effects of the space environment. This article summarizes the various lessons learned and offers recommendations to reduce or correct expected degradation with the goal of increasing the useful lifespan of future and ongoing space missions.

  18. Sonoelectrochemical degradation of triclosan in water.

    PubMed

    Ren, Yan-Ze; Franke, Marcus; Anschuetz, Franziska; Ondruschka, Bernd; Ignaszak, Anna; Braeutigam, Patrick

    2014-11-01

    The sonoelectrochemical degradation of triclosan in aqueous solutions with high-frequency ultrasound (850kHz) and various electrodes was investigated. Diamond coated niobium electrode showed the best results and was used as standard electrode, leading to effective degradation and positive synergistic effect. The influence of different parameters on the degradation degree and energy efficiency were evaluated and favorable reaction conditions were found. It could be shown that 92% of triclosan (1mgL(-1) aqueous solution) was degraded within 15min, following pseudo-first order kinetics.

  19. Antimisting kerosene: Low temperature degradation and blending

    NASA Technical Reports Server (NTRS)

    Yavrouian, A.; Parikh, P.; Sarohia, V.

    1988-01-01

    The inline filtration characteristics of freshly blended and degraded antimisting fuels (AMK) at low temperature are examined. A needle valve degrader was modified to include partial recirculation of degraded fuel and heat addition in the bypass loop. A pressure drop across the needle valve of up to 4,000 psi was used. The pressure drop across a 325 mesh filter screen placed inline with the degrader and directly downstream of the needle valve was measured as a function of time for different values of pressure drop across the needle valve. A volume flux of 1 gpm/sq in was employed based on the frontal area of the screen. It was found that, at ambient temperatures, freshly blended AMK fuel could be degraded using a single pass degradation at 4,000 psi pressure drop across the needle valve to give acceptable filterability performance. At fuel temperatures below -20 C, degradation becomes increasingly difficult and a single pass technique results in unacceptable filtration performance. Recirculation of a fraction of the degraded fuel and heat addition in the bypass loop improved low temperature degradation performance. The problem is addressed of blending the AMK additive with Jet A at various base fuel temperatures.

  20. Photovoltaic Degradation Rates -- An Analytical Review

    SciTech Connect

    Jordan, D. C.; Kurtz, S. R.

    2012-06-01

    As photovoltaic penetration of the power grid increases, accurate predictions of return on investment require accurate prediction of decreased power output over time. Degradation rates must be known in order to predict power delivery. This article reviews degradation rates of flat-plate terrestrial modules and systems reported in published literature from field testing throughout the last 40 years. Nearly 2000 degradation rates, measured on individual modules or entire systems, have been assembled from the literature, showing a median value of 0.5%/year. The review consists of three parts: a brief historical outline, an analytical summary of degradation rates, and a detailed bibliography partitioned by technology.

  1. Electricity from biogas

    SciTech Connect

    Augenstein, D.; Benemann, J.; Hughes, E.

    1994-12-31

    Biogas is a medium-Btu methane and carbon dioxide mix produced by bacterial decomposition of organic matter. Its sources include landfills, waste water sludges, and animal wastes. It can fuel energy applications, of which electricity generation is a frequently-preferred option. The greatest current U.S. biogas recovery and energy use is at landfills, where biogas at about 80 landfill sites fuels a total of approximately 300 MWe. Wastewater treatment plants and confined animal waste management systems support additional electric power production. Generation of electricity from biogas can present difficulties due to the generally small scale of the generating facility, variable energy content of the gas, fluctuating availability, contaminant problems, and often-demanding control needs. However, such difficulties are being successfully addressed and economics for electricity generation are often favorable as biogas can be essentially {open_quotes}free{close_quotes} fuel. Biogas recovery and use has the additional advantage of mitigating a potent greenhouse gas. Biogas from U.S. landfills alone could fuel about 1% of U.S. electrical generation while giving climate change benefit equivalent to reducing CO{sub 2} emissions in the electricity sector by more than 10%. Growth in landfill gas use will be facilitated by recent regulations, advances in equipment, and improved management techniques such as {open_quotes}controlled landfilling{close_quotes}. The potential for biogas recovery and electricity production from sewage sludges, animal wastes and other organic resources such as agricultural residues is uncertain but probably exceeds the estimate for landfills.

  2. Ceramic thermal barrier coatings for electric utility gas turbine engines

    NASA Technical Reports Server (NTRS)

    Miller, R. A.

    1986-01-01

    Research and development into thermal barrier coatings for electric utility gas turbine engines is reviewed critically. The type of coating systems developed for aircraft applications are found to be preferred for clear fuel electric utility applications. These coating systems consists of a layer of plasma sprayed zirconia-yttria ceramic over a layer of MCrAly bond coat. They are not recommended for use when molten salts are presented. Efforts to understand coating degradation in dirty environments and to develop corrosion resistant thermal barrier coatings are discussed.

  3. Correlation of magnetic properties with deformation in electrical steels

    NASA Astrophysics Data System (ADS)

    Papadopoulou, S.

    2016-03-01

    This paper investigates the utilization of magnetic Barkhausen Noise (MBN) and hysteresis loops methods for the non-destructive characterization of deformed electrical steel samples. For this reason electrical steel samples were subjected to uniaxial tensile tests on elastic and plastic region of deformations. Both the MBN and hysteresis loops were measured. The results shown a strong degradation of the magnetic properties on plastically strains. This was attributed to the irreversible movement of the magnetic domain walls, due to the presence of high dislocation density. The resulting magnetic properties were further evaluated by examining the microstructure of the deformed samples by using scanning electron microscopy.

  4. Electrical futures past.

    PubMed

    Gooday, Graeme J N

    2005-12-01

    Futurist writing about technology emerged in the late 19th century at the same time as new kinds of electrical technology were making utopian futures seem practically attainable. Electrical writers and novelists alike thus borrowed from the popular "science" fiction of Jules Verne, Edward Bellamy and others to try to create self-fulfilling prophecies of a future in which electrical gadgets and machines met all major practical needs of civilization. To the extent that many parts of our world are populated by the hardware that they forecast, they succeeded in their goal.

  5. Electric scooter pilot project

    NASA Astrophysics Data System (ADS)

    Slanina, Zdenek; Dedek, Jan; Golembiovsky, Matej

    2016-09-01

    This article describes the issue of electric scooter development for educational and demonstration purposes on the Technical University of Ostrava. Electric scooter is equipped with a brushless motor with permanent magnets and engine controller, measuring and monitoring system for speed regulation, energy flow control and both online and off-line data analysis, visualization system for real-time diagnostics and battery management with balancing modules system. Implemented device brings a wide area for the following scientific research. This article also includes some initial test results and electric vehicles experiences.

  6. Coaxial Electric Heaters

    NASA Technical Reports Server (NTRS)

    Strekalov, Dmitry; Matsko, Andrey; Savchenkov, Anatoliy; Maleki, Lute

    2008-01-01

    Coaxial electric heaters have been conceived for use in highly sensitive instruments in which there are requirements for compact heaters but stray magnetic fields associated with heater electric currents would adversely affect operation. Such instruments include atomic clocks and magnetometers that utilize heated atomic-sample cells, wherein stray magnetic fields at picotesla levels could introduce systematic errors into instrument readings. A coaxial electric heater is essentially an axisymmetric coaxial cable, the outer conductor of which is deliberately made highly electrically resistive so that it can serve as a heating element. As in the cases of other axisymmetric coaxial cables, the equal magnitude electric currents flowing in opposite directions along the inner and outer conductors give rise to zero net magnetic field outside the outer conductor. Hence, a coaxial electric heater can be placed near an atomic-sample cell or other sensitive device. A coaxial electric heater can be fabricated from an insulated copper wire, the copper core of which serves as the inner conductor. For example, in one approach, the insulated wire is dipped in a colloidal graphite emulsion, then the emulsion-coated wire is dried to form a thin, uniform, highly electrically resistive film that serves as the outer conductor. Then the film is coated with a protective layer of high-temperature epoxy except at the end to be electrically connected to the power supply. Next, the insulation is stripped from the wire at that end. Finally, electrical leads from the heater power supply are attached to the exposed portions of the wire and the resistive film. The resistance of the graphite film can be tailored via its thickness. Alternatively, the film can be made from an electrically conductive paint, other than a colloidal graphite emulsion, chosen to impart the desired resistance. Yet another alternative is to tailor the resistance of a graphite film by exploiting the fact that its resistance

  7. Electric Propulsion Study

    DTIC Science & Technology

    1990-08-01

    DTIC FILE COPY AL-TR-89-040 AD: AD-A227 121 Final Report forteprod Electric Propulsion Study 21 Sep 1988 to 30 Nov 1989 DTIC ’ELECTE0OCT 0c 41990u... Electric Propulsion Study (U) 12. PERSONAL AUTHOR(S) Cravens, Dennis J. 13a. TYPE OF REPORT 13b. TIME COVERED 14. DATE OF REPORT (Year, Month, Day) 15. PAGE...identif bv block number) FIELD GROUP SUB-GROUP Inductive theories, electric propulsion, unified field 21 0- theories, Conservatc!±,n Laws, Dynamic

  8. BEEST: Electric Vehicle Batteries

    SciTech Connect

    2010-07-01

    BEEST Project: The U.S. spends nearly a $1 billion per day to import petroleum, but we need dramatically better batteries for electric and plug-in hybrid vehicles (EV/PHEV) to truly compete with gasoline-powered cars. The 10 projects in ARPA-E’s BEEST Project, short for “Batteries for Electrical Energy Storage in Transportation,” could make that happen by developing a variety of rechargeable battery technologies that would enable EV/PHEVs to meet or beat the price and performance of gasoline-powered cars, and enable mass production of electric vehicles that people will be excited to drive.

  9. Atoms to electricity. [Booklet

    SciTech Connect

    Not Available

    1987-11-01

    This booklet explains the basic technology of nuclear fission power reactors, the nuclear fuel cycle and the role of nuclear energy as one of the domestic energy resources being developed to help meet our national energy demand. Nuclear power accounted for over 16 percent of the US electric energy supply in 1986 and was second only to coal as a source of our electric power. In the 1990s, nuclear energy is expected to provide almost 20 percent of the Nation's electricity. 38 figs., 5 tabs.

  10. Contactless Rotary Electrical Couplings

    NASA Technical Reports Server (NTRS)

    Kumagai, Hiroyuki

    2003-01-01

    Rotary electrical couplings based on induction (transformer action) rather than conduction between rotating and stationary circuitry have been invented. These couplings provide an alternative to slip rings and contact brushes. Mechanical imperfections of slip-ring and brush contact surfaces and/or dust particles trapped between these surfaces tend to cause momentary interruptions in electrical contact and thereby give rise to electrical noise. This source of noise can be eliminated in the inductive rotary couplings because no direct contact is necessary for transformer action.

  11. Mechanisms of humic substances degradation by fungi

    NASA Astrophysics Data System (ADS)

    Chen, Y.; Hadar, Y.; Grinhut, T.

    2012-04-01

    Humic substances (HS) are formed by secondary synthesis reactions (humification) during the decay process and transformation of biomolecules originating from plants and other dead organisms. In nature, HS are extremely resistant to biological degradation. Thus, these substances are major components in the C cycle and in the biosphere and therefore, the understanding of the process leading to their formation and transformation and degradation is vital. Fungi active in the decomposition process of HS include mainly ascomycetes and basidiomycetes that are common in the upper layer of forest and grassland soils. Many basidiomycetes belong to the white-rot fungi (WRF) and litter-decomposing fungi (LDF). These fungi are considered to be the most efficient lignin degraders due to their nonspecific oxidizing enzymes: manganese peroxidase (MnP), lignin peroxidase (LiP) and laccase. Although bacteria dominate compost and participate in the turnover of HS, their ability to degrade stable macromolecules such as lignin and HS is limited. The overall objectives of this research were to corroborate biodegradation processes of HS by WRF. The specific objectives were: (i) To isolate, identify and characterize HS degrading WRF from biosolids (BS) compost; (ii) To study the biodegradation process of three types of HS, which differ in their structure, by WRF isolated from BS compost; and (iii) To investigate the mechanisms of HA degradation by WRF using two main approaches: (a) Study the physical and chemical analyses of the organic compounds obtained from direct fungal degradation of HA as well as elucidation of the relevant enzymatic reactions; and (b) Study the enzymatic and biochemical mechanisms involved during HA degradation. In order to study the capability of fungi to degrade HS, seventy fungal strains were isolated from biosolids (BS) compost. Two of the most active fungal species were identified based on rDNA sequences and designated Trametes sp. M23 and Phanerochaetesp., Y6

  12. Electrical Researches of Henry Cavendish

    NASA Astrophysics Data System (ADS)

    Clerk Maxwell, James; Cavendish, Henry

    2010-05-01

    Introduction; Account of Cavendish's writings on electricity; 1. First published papers on electricity; 2. Preliminary propositions; 3. Appendix; 4. Thoughts concerning electricity; 5. Account of the experiments; 6. Second published paper on electricity; 7. Experiments in 1771; 8. Experiments in 1772; 9. Index to electrical experiments, 1773; 10. Measures; 11. Experiments with the artificial torpedo; 12. Resistance to electricity; 13. Calibration of tubes; 14. Resistance of copper wire; 15. Result; 16. Results; Notes by the editor; Index.

  13. Influence of low- and high-frequency heating on biodegrading microorganisms in soil: microbial degradation.

    PubMed

    Roland, Ulf; Holzer, Frank; Kopinke, Frank-Dieter

    2013-01-01

    The influence of low-frequency (50 Hz) resistive and high-frequency (13.56 MHz, radio-frequency) dielectric heating in comparison to conventional heating on the microbial degradation of pollutants in soil was studied. The investigation of the biodegradation of model substances (benzoic acid, acetic acid, glucose, sodium acetate) added to a standard soil showed no significant influence of the electrical heating methods when compared with samples heated to the same temperature in a water bath. Therefore, a hindrance of the microbial degradation could be excluded as it was done for soil respiration in a previous study. This finding is especially relevant for the application of these electrical heating methods for thermally enhanced soil bioremediation as an option for making in situ or ex situ clean-up processes more efficient.

  14. Degradation of Endeavour crater, Mars

    NASA Astrophysics Data System (ADS)

    Grant, J. A., III; Crumpler, L. S.; Parker, T. J.; Golombek, M. P.

    2014-12-01

    The Opportunity rover is traversing the western rim segments of the 22 km diameter Endeavour crater in Meridiani Planum, with resultant data enabling evaluation of the craters's degradation state. The crater is Noachian in age, complex in morphology, and largely buried by younger sulfate-rich rocks. Nevertheless, exposed rim segments dubbed Cape York (CY) and Solander Point/Murray Ridge (S/M) ~1500 m to the south reveal breccias interpreted as remnants of the ejecta deposit (Shoemaker Formation or SF) that at CY overlie the pre-impact country rocks (Matijevic Formation or MF). At CY, relief is ~10 m and consists of 6-7 m of SF over at least several m of MF. By contrast, the MF/SF contact is not visible at S/M despite outcrops some 20 m below and 60 m above the elevation of the contact at CY. This implies some structural offset between the rim segments and suggests up to 70 m section is preserved at S/M. The lack of information about the orientation of the SF at S/M makes the true thickness difficult to establish, though it appears to be 10's of m more than at CY. Comparison to similar sized, fresh, complex craters on Mars and the Moon suggests there was originally 100-200 m of ejecta at Endeavour's rim. Ejecta comprise only 20-25% of the rim relief around lunar craters of similar size, thereby implying an original rim height of up to 500-1000 m at Endeavour. If accurate, then ~400-800 m of the rim remains buried; the higher end of this range is close to the 800-900 m section interpreted elsewhere. If 200 m ejecta were present, then CY and S/M experienced ~190 m and over 100 m erosional lowering, respectively. If 100 m ejecta were present then rim lowering was ~90 m and 10's of m, respectively. Such differences between rim segments likely relate to changing efficiency of responsible processes and/or varying characteristics of the rocks and indicate portions of Endeavour crater experienced significant degradation. A paucity of exposed debris shed from SF and MT

  15. Solar Electric Propulsion (SEP)

    NASA Video Gallery

    Future Human Exploration requires high power solar electric propulsion vehicles to move cargo and humans beyond Low Earth Orbit, which requires large light weight arrays, high power processing, and...

  16. Electrical Subsurface Grounding Analysis

    SciTech Connect

    J.M. Calle

    2000-11-01

    The purpose and objective of this analysis is to determine the present grounding requirements of the Exploratory Studies Facility (ESF) subsurface electrical system and to verify that the actual grounding system and devices satisfy the requirements.

  17. Micromachined electrical cauterizer

    DOEpatents

    Lee, A.P.; Krulevitch, P.A.; Northrup, M.A.

    1999-08-31

    A micromachined electrical cauterizer is disclosed. Microstructures are combined with microelectrodes for highly localized electro cauterization. Using boron etch stops and surface micromachining, microneedles with very smooth surfaces are made. Micromachining also allows for precision placement of electrodes by photolithography with micron sized gaps to allow for concentrated electric fields. A microcauterizer is fabricated by bulk etching silicon to form knife edges, then parallelly placed microelectrodes with gaps as small as 5 {mu}m are patterned and aligned adjacent the knife edges to provide homeostasis while cutting tissue. While most of the microelectrode lines are electrically insulated from the atmosphere by depositing and patterning silicon dioxide on the electric feedthrough portions, a window is opened in the silicon dioxide to expose the parallel microelectrode portion. This helps reduce power loss and assist in focusing the power locally for more efficient and safer procedures. 7 figs.

  18. Micromachined electrical cauterizer

    DOEpatents

    Lee, Abraham P.; Krulevitch, Peter A.; Northrup, M. Allen

    1999-01-01

    A micromachined electrical cauterizer. Microstructures are combined with microelectrodes for highly localized electro cauterization. Using boron etch stops and surface micromachining, microneedles with very smooth surfaces are made. Micromachining also allows for precision placement of electrodes by photolithography with micron sized gaps to allow for concentrated electric fields. A microcauterizer is fabricated by bulk etching silicon to form knife edges, then parallelly placed microelectrodes with gaps as small as 5 .mu.m are patterned and aligned adjacent the knife edges to provide homeostasis while cutting tissue. While most of the microelectrode lines are electrically insulated from the atmosphere by depositing and patterning silicon dioxide on the electric feedthrough portions, a window is opened in the silicon dioxide to expose the parallel microelectrode portion. This helps reduce power loss and assist in focusing the power locally for more efficient and safer procedures.

  19. Electric current locator

    DOEpatents

    King, Paul E [Corvallis, OR; Woodside, Charles Rigel [Corvallis, OR

    2012-02-07

    The disclosure herein provides an apparatus for location of a quantity of current vectors in an electrical device, where the current vector has a known direction and a known relative magnitude to an input current supplied to the electrical device. Mathematical constants used in Biot-Savart superposition equations are determined for the electrical device, the orientation of the apparatus, and relative magnitude of the current vector and the input current, and the apparatus utilizes magnetic field sensors oriented to a sensing plane to provide current vector location based on the solution of the Biot-Savart superposition equations. Description of required orientations between the apparatus and the electrical device are disclosed and various methods of determining the mathematical constants are presented.

  20. Home Electrical Safety Checklist

    MedlinePlus

    ... wall, baseboard, etc) with nails or wire staples ? YES: Remove any nails and/or staples and replace damaged cords. ... shock (other than one from static electricity) from any appliance? YES: Do not touch the appliance until it has ...

  1. Electrically driven optical antennas

    NASA Astrophysics Data System (ADS)

    Kern, Johannes; Kullock, René; Prangsma, Jord; Emmerling, Monika; Kamp, Martin; Hecht, Bert

    2015-09-01

    Unlike radiowave antennas, so far optical nanoantennas cannot be fed by electrical generators. Instead, they are driven by light or indirectly via excited discrete states in active materials in their vicinity. Here we demonstrate the direct electrical driving of an in-plane optical antenna by the broadband quantum-shot noise of electrons tunnelling across its feed gap. The spectrum of the emitted photons is determined by the antenna geometry and can be tuned via the applied voltage. Moreover, the direction and polarization of the light emission are controlled by the antenna resonance, which also improves the external quantum efficiency by up to two orders of magnitude. The one-material planar design offers facile integration of electrical and optical circuits and thus represents a new paradigm for interfacing electrons and photons at the nanometre scale, for example for on-chip wireless communication and highly configurable electrically driven subwavelength photon sources.

  2. Electrically conductive material

    DOEpatents

    Singh, Jitendra P.; Bosak, Andrea L.; McPheeters, Charles C.; Dees, Dennis W.

    1993-01-01

    An electrically conductive material for use in solid oxide fuel cells, electrochemical sensors for combustion exhaust, and various other applications possesses increased fracture toughness over available materials, while affording the same electrical conductivity. One embodiment of the sintered electrically conductive material consists essentially of cubic ZrO.sub.2 as a matrix and 6-19 wt. % monoclinic ZrO.sub.2 formed from particles having an average size equal to or greater than about 0.23 microns. Another embodiment of the electrically conductive material consists essentially at cubic ZrO.sub.2 as a matrix and 10-30 wt. % partially stabilized zirconia (PSZ) formed from particles having an average size of approximately 3 microns.

  3. Electrically conductive material

    DOEpatents

    Singh, J.P.; Bosak, A.L.; McPheeters, C.C.; Dees, D.W.

    1993-09-07

    An electrically conductive material is described for use in solid oxide fuel cells, electrochemical sensors for combustion exhaust, and various other applications possesses increased fracture toughness over available materials, while affording the same electrical conductivity. One embodiment of the sintered electrically conductive material consists essentially of cubic ZrO[sub 2] as a matrix and 6-19 wt. % monoclinic ZrO[sub 2] formed from particles having an average size equal to or greater than about 0.23 microns. Another embodiment of the electrically conductive material consists essentially at cubic ZrO[sub 2] as a matrix and 10-30 wt. % partially stabilized zirconia (PSZ) formed from particles having an average size of approximately 3 microns. 8 figures.

  4. Ideas To Save Electricity

    ERIC Educational Resources Information Center

    Gardner, John C.

    1974-01-01

    Significant energy savings can be effected through stopping obvious waste of water, electricity, and heat; purchasing equipment with the correct voltage and horsepower; equipment maintenance; and redesigning or replacing obsolete or inefficient equipment. (Author/MF)

  5. Biomass for Electricity Generation

    EIA Publications

    2002-01-01

    This paper examines issues affecting the uses of biomass for electricity generation. The methodology used in the National Energy Modeling System to account for various types of biomass is discussed, and the underlying assumptions are explained.

  6. Corrosion Preventative Compounds (CPCs) Effect on Aircraft Electrical Wiring Components

    DTIC Science & Technology

    2011-08-01

    degrade certain types of elastomers . • are susceptible to entrapping contaminants. CPC Effect on Aircraft Electrical Wiring Components...early 1980’s on many Navy aircraft. The Navy’s standard wire type. M5086/2-20 c Polyvinyl chloride, polyamide jacket, glass fiber braid (PVC/glass...connector type does not have a wire sealing grommet, so the same type of frictional forces from the elastomer are not encountered. 4.2.2

  7. ELECTRIC MOTOR CARS.

    DTIC Science & Technology

    The electric automobiles studied are designed as the equivalent of their gasoline-engine counterparts in size, comfort, performance, and initial...acceleration. Top speeds comparable to those of small present-day cars are shown to be realizable, though the range between refueling is not. Batteries...noise abatement. The lifetime costs derived can be somewhat lower than those of conventional cars ; therefore it is concluded that electric cars

  8. Electrically charged targets

    DOEpatents

    Goodman, Ronald K.; Hunt, Angus L.

    1984-01-01

    Electrically chargeable laser targets and method for forming such charged targets in order to improve their guidance along a predetermined desired trajectory. This is accomplished by the incorporation of a small amount of an additive to the target material which will increase the electrical conductivity thereof, and thereby enhance the charge placed upon the target material for guidance thereof by electrostatic or magnetic steering mechanisms, without adversely affecting the target when illuminated by laser energy.

  9. Renewable Electricity Futures (Presentation)

    SciTech Connect

    Hand, M. M.

    2012-08-01

    This presentation library summarizes findings of NREL's Renewable Electricity Futures study, published in June 2012. RE Futures investigated the challenges and impacts of achieving very high renewable electricity generation levels in the contiguous United States by 2050. It was presented to the 2012 Western Conference of Public Service Commissioners, during their June, 2012, meeting. The Western Conference of Public Service Commissioners is a regional association within the National Association of Regulatory Utility Commissioners (NARUC).

  10. Electric power annual 1993

    SciTech Connect

    Not Available

    1994-12-08

    This report presents a summary of electric power industry statistics at national, regional, and state levels: generating capability and additions, net generation, fossil-fuel statistics, retail sales and revenue, finanical statistics, environmental statistics, power transactions, demand side management, nonutility power producers. Purpose is to provide industry decisionmakers, government policymakers, analysts, and the public with historical data that may be used in understanding US electricity markets.

  11. Electrically Mediated Trauma Repair.

    DTIC Science & Technology

    1987-12-01

    axons within the hemisected spinal cord of the adult guinea pig (Borgens et al., 1986). b. That this electrically facilitated regeneration is...months after thoracic right lateral hemisection of the spinal cord (arrow). A) The back skin of the guinea pig shaved and marked with ink grid lines. B...Next page) (From Science article: Behavioral Recovery Induced by Applied Electric Fields After Spinal Cord Hemisection in Guinea Pig, Volume 238, PP

  12. Ion electric propulsion unit

    DOEpatents

    Light, Max E; Colestock, Patrick L

    2014-01-28

    An electron cyclotron resonance (ECR) thruster is disclosed having a plasma chamber which is electrically biased with a positive voltage. The chamber bias serves to efficiently accelerate and expel the positive ions from the chamber. Electrons follow the exiting ions, serving to provide an electrically neutral exhaust plume. In a further embodiment, a downstream shaping magnetic field serves to further accelerate and/or shape the exhaust plume.

  13. Electrical Stress Test (EST)

    DTIC Science & Technology

    2015-03-11

    PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Fuze and Precision Armaments Technology Directorate U.S. Army Armament Research, Development and...evaluation of weapon system fuzes and fuze components. The primary purpose of the test guideline is to standardize various credible stressing electrical...ORDNANCE TEST PROCEDURE (JOTP)-053 ELECTRICAL STRESS TEST DoD Fuze Engineering Standardization Working Group (FESWG) DISTRIBUTION

  14. Environmental Degradation of High Temperature Composites

    DTIC Science & Technology

    1992-04-01

    A study was performed to assess the effect of galvanic corrosion phenomena on the strength of graphite/bismaleimide( BMI ) composites . The results...indicate that degradation occurred in BMI composites galvanically coupled to aluminum alloys. The mechanism responsible for the degradation involves

  15. Geodiversity and land degradation in Hungary

    NASA Astrophysics Data System (ADS)

    Őrsi, Anna

    2014-05-01

    Geodiversity represents a variety of natural values, but they are threatened by a series of anthropogenic activities and land degradation processes. Their effect depends on the intensity of the processes and the sensitivity of the area in question. As a consequence of land degradation processes not only biodiversity but also geodiversity can be damaged and deteriorated. The appearance of the natural landscape changes and natural processes may not have a decisive role in landscape development any more. Some of the damages are irreversible because fundamental changes happen in the landscape, or the processes having created the original forms are no longer in operation. Small scale land degradation processes may be reversible if nature is still capable of reproducing the original state. The most important land degradation processes are desertification and soil erosion. Mining, waste disposal, urbanisation and construction activities, agriculture, inaccurate forest and water management, tourism, unsuitable land use can also lead to severe land degradation problems. The objective of the paper is to show Hungarian examples to all land degradation processes that threaten geodiversity. The results will be shown on a series of maps showing land degradation processes endangering geodiversity in Hungary. A detailed analysis of smaller study sites will be provided to show the effects of certain land degradation processes on landform development and on the changes of geodiversity. This research is supported by the Hungarian Scientific Research Fund (OTKA), project Nr. 10875.

  16. Degradation and Characterization of Antimisting Kerosene (AMK).

    DTIC Science & Technology

    1982-12-01

    PRESSURE TRANSDUCER (0-10 psi) GTHROUGH FLOW (TO ENGINE) WASH FLOW (TO FUEL CONTROLLER) FIGURE 2. J1SD FUEL FILTERS I3 -- PSI HGH PR ESSU RE T... bui ld-up of pressure with degraded ANK than with ,Jet A (see F igs. 4 and 5) . Similar results were reported with fuel that was degraded by three

  17. Photoelectrocatalytic degradation of formic acid using a porous TiO[sub 2] thin-film electrode

    SciTech Connect

    Kim, D.H.; Anderson, M.A. )

    1994-03-01

    The degradation of formic acid (HCOOH) using titanium dioxide (TiO[sub 2]) in photocatalytic and photoelectrocatalytic reactions was investigated in order to determine whether electrical biasing could improve the efficiency of photocatalytic reactions. This study addressed the effects of film thickness, biasing potential, presence of oxygen, and added inorganic electrolytes on the photocatalytic degradation of HCOOH. The results of these experiments showed that the degradation of HCOOH in this system was due only to the photocatalytic as opposed to homogeneous photolysis reactions. Degradation efficiency of the photocatalytic reaction was roughly proportional to the TiO[sub 2] film thickness. In the photoelectrocatalytic reaction, positive potentials (vs saturated calomel electrode, SCE) improved the degradation efficiency and +0.0 V (vs SCE) was enough to obtain a maximum efficiency. The supply of oxygen was essential in the photocatalytic reaction, while the photoelectrocatalytic reaction was not significantly affected by the removal of oxygen. The presence of inorganic electrolytes lowered the efficiency of the photocatalytic degradation of HCOOH. However, the efficiency of photoelectrocatalytic degradation was not affected by inorganic electrolytes. Overall, when used with the bias, the system showed efficient degradation over a wide range of conditions. 21 refs., 9 figs.

  18. Impedance Characterization of the Degradation of Insulating Layer Patterned on Interdigitated Microelectrode.

    PubMed

    Lee, Gihyun; Kim, Sohee; Cho, Sungbo

    2015-10-01

    Life-time and functionality of planar microelectrode-based devices are determined by not only the corrosion-resistance of the electrode, but also the durability of the insulation layer coated on the transmission lines. Degradation of the insulating layer exposed to a humid environment or solution may cause leakage current or signal loss, and a decrease in measurement sensitivity. In this study, degradation of SU-8, an epoxy-based negative photoresist and insulating material, patterned on Au interdigitated microelectrode (IDE) for long-term (>30 days) immersion in an electrolyte at 37 °C was investigated by electrical impedance spectroscopy and theoretical equivalent circuit modeling. From the experiment and simulation results, it was found that the degradation level of the insulating layer of the IDE electrode can be characterized by monitoring the resistance of the insulating layer among the circuit parameters of the designed equivalent circuit modeling.

  19. Physics Based Electrolytic Capacitor Degradation Models for Prognostic Studies under Thermal Overstress

    NASA Technical Reports Server (NTRS)

    Kulkarni, Chetan S.; Celaya, Jose R.; Goebel, Kai; Biswas, Gautam

    2012-01-01

    Electrolytic capacitors are used in several applications ranging from power supplies on safety critical avionics equipment to power drivers for electro-mechanical actuators. This makes them good candidates for prognostics and health management research. Prognostics provides a way to assess remaining useful life of components or systems based on their current state of health and their anticipated future use and operational conditions. Past experiences show that capacitors tend to degrade and fail faster under high electrical and thermal stress conditions that they are often subjected to during operations. In this work, we study the effects of accelerated aging due to thermal stress on different sets of capacitors under different conditions. Our focus is on deriving first principles degradation models for thermal stress conditions. Data collected from simultaneous experiments are used to validate the desired models. Our overall goal is to derive accurate models of capacitor degradation, and use them to predict performance changes in DC-DC converters.

  20. Withstanding voltage degradation of EEE components due to cavity pressure loss

    NASA Astrophysics Data System (ADS)

    Rieger, Rolf; Regula, Michael; Pedersen, Ole

    1991-03-01

    Hermeticity problems of Electric, Electronic and Electromechanical (EEE) components are discussed. Ways of withstanding voltage degradation of components designed and qualified for operating voltages of greater than or equal to 50 volts are described. The underlying physical background of the problem is discussed. Experimental results are presented illustrating gas discharge phenomena, glow discharge, and arc discharge. Glow discharge of several representative two wire gaps (0.5 through 10 mm) are presented. Experimental set ups and results are shown in diagrammatic form.