Effect of energetic electrons on dust charging in hot cathode filament discharge

International Nuclear Information System (INIS)

Kakati, B.; Kausik, S. S.; Saikia, B. K.; Bandyopadhyay, M.

2011-01-01

The effect of energetic electrons on dust charging for different types of dust is studied in hydrogen plasma. The hydrogen plasma is produced by hot cathode filament discharge method in a dusty plasma device. A full line cusped magnetic field cage is used to confine the plasma elements. To study the plasma parameters for various discharge conditions, a cylindrical Langmuir probe having 0.15 mm diameter and 10.0 mm length is used. An electronically controlled dust dropper is used to drop the dust particles into the plasma. For different discharge conditions, the dust current is measured using a Faraday cup connected to an electrometer. The effect of secondary emission as well as discharge voltage on charging of dust grains in hydrogen plasma is studied with different dust.

Self-induced optogalvanic effect in a segmented hollow-cathode discharge

Science.gov (United States)

Steflekova, V.; Zhechev, D.

2018-03-01

Optogalvanic (OG) interaction is simulated and studied in a segmented hollow-cathode discharge (SHCD). HCD-lamps are used to induce an OG signal by their own emission or by that of another lamp. The efficiency of the OG of a Ne/Cu HCD lamp in the range 320-380 nm is estimated theoretically. An irregular galvanic peak arising near the inflection point in the i-V curve (∂V/∂i<0) is detected. Its origin is related to Penning ionization of the sputtered cathode material.

Development of plasma cathode electron guns

Science.gov (United States)

Oks, Efim M.; Schanin, Peter M.

1999-05-01

The status of experimental research and ongoing development of plasma cathode electron guns in recent years is reviewed, including some novel upgrades and applications to various technological fields. The attractiveness of this kind of e-gun is due to its capability of creating high current, broad or focused beams, both in pulsed and steady-state modes of operation. An important characteristic of the plasma cathode electron gun is the absence of a thermionic cathode, a feature which leads to long lifetime and reliable operation even in the presence of aggressive background gas media and at fore-vacuum gas pressure ranges such as achieved by mechanical pumps. Depending on the required beam parameters, different kinds of plasma discharge systems can be used in plasma cathode electron guns, such as vacuum arcs, constricted gaseous arcs, hollow cathode glows, and two kinds of discharges in crossed E×B fields: Penning and magnetron. At the present time, plasma cathode electron guns provide beams with transverse dimension from fractional millimeter up to about one meter, beam current from microamperes to kiloamperes, beam current density up to about 100 A/cm2, pulse duration from nanoseconds to dc, and electron energy from several keV to hundreds of keV. Applications include electron beam melting and welding, surface treatment, plasma chemistry, radiation technologies, laser pumping, microwave generation, and more.

Development of hollow anode penning ion source for laboratory application

Energy Technology Data Exchange (ETDEWEB)

Das, B.K., E-mail: dasbabu31@gmail.com [Energetics and Electromagnetics Division, Bhabha Atomic Research Centre, Autonagar, Visakhapatnam (India); Shyam, A.; Das, R. [Energetics and Electromagnetics Division, Bhabha Atomic Research Centre, Autonagar, Visakhapatnam (India); Rao, A.D.P. [Department of Nuclear Physics, Andhra University, Visakhapatnam (India)

2012-03-21

The research work presented here focuses for the development of miniature penning type ion source. One hollow anode penning type ion source was developed in our laboratory. The size of the ion source is 38 mm diameter and 55 mm length. The ion source consists of two cathodes, a hollow anode and one piece of rare earth permanent magnet. The plasma was created in the plasma region between cathodes and the hollow anode. The J Multiplication-Sign B force in the region helps for efficient ionization of the gas even in the high vacuum region{approx}1 Multiplication-Sign 10{sup -5} Torr. The ions were extracted in the axial direction with help of the potential difference between the electrodes and the geometry of the extraction angle. The effect of the extraction electrode geometry for efficient extraction of the ions from the plasma region was examined. This ion source is a self extracted ion source. The self extracted phenomena reduce the cost and the size of the ion source. The extracted ion current was measured by a graphite probe. An ion current of more than 200 {mu}A was observed at the probe placed 70 mm apart from the extraction electrode. In this paper, the structure of the ion source, effect of operating pressure, potential difference and the magnetic field on the extracted ion current is reported.

Cathode Effects in Cylindrical Hall Thrusters

Energy Technology Data Exchange (ETDEWEB)

Granstedt, E.M.; Raitses, Y.; Fisch, N. J.

2008-09-12

Stable operation of a cylindrical Hall thruster (CHT) has been achieved using a hot wire cathode, which functions as a controllable electron emission source. It is shown that as the electron emission from the cathode increases with wire heating, the discharge current increases, the plasma plume angle reduces, and the ion energy distribution function shifts toward higher energies. The observed effect of cathode electron emission on thruster parameters extends and clarifies performance improvements previously obtained for the overrun discharge current regime of the same type of thruster, but using a hollow cathode-neutralizer. Once thruster discharge current saturates with wire heating, further filament heating does not affect other discharge parameters. The saturated values of thruster discharge parameters can be further enhanced by optimal placement of the cathode wire with respect to the magnetic field.

Beam-plasma interaction in a cold-cathodes penning discharge

International Nuclear Information System (INIS)

Bliman, S.L.

1966-06-01

The H.F. emissions from a cold-cathode reflex discharge are studied. An experimental law for the frequency variation shows that fαV 1/2 discharged if B 0 and p are constant. If B 0 is made to increase, the frequencies change such that f ce - f emitted / f ce decreases. With each emitted frequency there is associated a stationary wave system making it possible to measure the phase velocity Vφ of the waves. This phase velocity is always close to that of the fast electrons accelerated by a potential V discharge. A non-quasistatic formalism for the propagation of waves in a beam-plasma system is then established. The Maxwell equations are solved taking into account boundary conditions. Comparison of these experiments with the theory shows a satisfactory agreement. (author) [fr

Ionization and excitation of uranium in a hollow-cathode lamp

International Nuclear Information System (INIS)

Gagne, J.M.; Pianarosa, P.; Larin, G.; Saint-Dizier, J.P.; Bouchard, P.

1981-01-01

The influence of different carrier gases (Ne,Ar,Kr,Xe) their pressure, and discharge current on the excitation and ionization of uranium atoms in a vapor generator of hollow-cathode design has been investigated by monitoring emission line intensities. From our measurements of line intensities as a function of the carrier gas we obtain an indication of the role of Penning collisions on the excitation of radiative levels in U II

Chemically stable Au nanorods as probes for sensitive surface enhanced scattering (SERS) analysis of blue BIC ballpoint pens

Science.gov (United States)

Alyami, Abeer; Saviello, Daniela; McAuliffe, Micheal A. P.; Cucciniello, Raffaele; Mirabile, Antonio; Proto, Antonio; Lewis, Liam; Iacopino, Daniela

2017-08-01

Au nanorods were used as an alternative to commonly used Ag nanoparticles as Surface Enhanced Raman Scattering (SERS) probes for identification of dye composition of blue BIC ballpoint pens. When used in combination with Thin Layer Chromatography (TLC), Au nanorod colloids allowed identification of the major dye components of the BIC pen ink, otherwise not identifiable by normal Raman spectroscopy. Thanks to their enhanced chemical stability compared to Ag colloids, Au nanorods provided stable and reproducible SERS signals and allowed easy identification of phthalocyanine and triarylene dyes in the pen ink mixture. These findings were supported by FTIR and MALDI analyses, also performed on the pen ink. Furthermore, the self-assembly of Au nanorods into large area ordered superstructures allowed identification of BIC pen traces. SERS spectra of good intensity and high reproducibility were obtained using Au nanorod vertical arrays, due to the high density of hot spots and morphological reproducibility of these superstructures. These results open the way to the employment of SERS for fast screening analysis and for quantitative analysis of pens and faded pens which are relevant for the fields of forensic and art conservation sciences.

Study of ion viscosity by spontaneous L-H transitions under marginal hot cathode biasing in the Tohoku University Heliac

International Nuclear Information System (INIS)

Kitajima, S.; Takahashi, H.; Tanaka, Y.; Utoh, H.; Takenaga, M.; Yokoyama, M.; Inagaki, S.; Suzuki, Y.; Nishimura, K.; Ogawa, H.; Takayama, M.; Shinde, J.; Ogawa, M.; Aoyama, H.; Iwazaki, K.; Okamoto, A.; Shinto, K.; Sasao, M.

2008-01-01

Using the spontaneous transition condition under marginal hot cathode biasing, the ion viscosity at the L-H transition was estimated in various magnetic configurations in the Tohoku University Heliac. The critical viscosity, which is the viscosity at the transition point, was experimentally estimated from the J x B driving force. The critical viscosities in different magnetic configurations were in agreement with the neoclassical predictions within a factor of 2 and were compared with the viscosities obtained in the externally forced biasing experiments. Although the transition points were spread over a wide range, poloidal Mach numbers at the transition point were concentrated near the viscosity maxima predicted by the theory

A hot-spare injector for the APS linac

International Nuclear Information System (INIS)

Lewellen, J. W.

1999-01-01

Last year a second-generation SSRL-type thermionic cathode rf gun was installed in the Advanced Photon Source (APS) linac. This gun (referred to as ''gun2'') has been successfully commissioned and now serves as the main injector for the APS linac, essentially replacing the Koontz-type DC gun. To help ensure injector availability, particularly with the advent of top-up mode operation at the APS, a second thermionic-cathode rf gun will be installed in the APS linac to act as a hot-spare beam source. The hot-spare installation includes several unique design features, including a deep-orbit Panofsky-style alpha magnet. Details of the hot-spare beamline design and projected performance are presented, along with some plans for future performance upgrades

Investigation of chlorination of zirconium and hafnium and their compounds in discharge from hollow cathode

International Nuclear Information System (INIS)

Ioffe, R.B.; Korovin, Yu.I.

1978-01-01

The possibility is investigated of chlorinating various zirconium and hafnium compounds (metal, oxide, carbide) in a hot discharge from a hollow cathode with various chlorinating reagents: copper monochloride, nickel chloride, magnesium chloride, for the purpose of accelerating their entrance into the excitation zone. It has been shown thermodynamically and experimentally that chlorination of metal zirconium and hafnium and their carbides with copper monochloride in hot hollow cathode conditions provides a sharp increase in the intensity of the lines of these elements

Solid oxide fuel cell power plant having a fixed contact oxidation catalyzed section of a multi-section cathode air heat exchanger

Science.gov (United States)

Saito, Kazuo; Lin, Yao

2015-02-17

The multi-section cathode air heat exchanger (102) includes at least a first heat exchanger section (104), and a fixed contact oxidation catalyzed section (126) secured adjacent each other in a stack association. Cool cathode inlet air flows through cool air channels (110) of the at least first (104) and oxidation catalyzed sections (126). Hot anode exhaust flows through hot air channels (124) of the oxidation catalyzed section (126) and is combusted therein. The combusted anode exhaust then flows through hot air channels (112) of the first section (104) of the cathode air heat exchanger (102). The cool and hot air channels (110, 112) are secured in direct heat exchange relationship with each other so that temperatures of the heat exchanger (102) do not exceed 800.degree. C. to minimize requirements for using expensive, high-temperature alloys.

An evaluation of prefilled insulin pens: a focus on the Next Generation FlexPen®

Directory of Open Access Journals (Sweden)

Estella M Davis

2010-08-01

Full Text Available Estella M Davis, Emily L Sexson, Mikayla L Spangler, Pamela A ForalDepartment of Pharmacy Practice, Creighton University School of Pharmacy and Health Professions, Omaha, Nebraska, USAAbstract: Insulin pen delivery systems are preferred by patients over the traditional vial and syringe method for insulin delivery because they are simple and easy to use, improve confidence in dosing insulin, and have less interference with activities and improved discretion with use. Insulin manufacturers have made numerous improvements to their first marketed pen devices and are now introducing their next generation of devices. Design modifications to the newest generation of prefilled insulin pen devices are intended to improve the ease of use and safety and continue to positively impact adherence to insulin. This review focuses on the Next Generation FlexPen® with regard to design considerations to reduce injection force, improve accuracy and ease of use, and evaluate the preference of patient and health-care provider compared with other disposable, prefilled insulin pen devices.Keywords: diabetes, dose accuracy, injection force, patient preference, insulin pen device

Vegetation survey of PEN Branch wetlands

Energy Technology Data Exchange (ETDEWEB)

1991-01-01

A survey was conducted of vegetation along Pen Branch Creek at Savannah River Site (SRS) in support of K-Reactor restart. Plants were identified to species by overstory, understory, shrub, and groundcover strata. Abundance was also characterized and richness and diversity calculated. Based on woody species basal area, the Pen Branch delta was the most impacted, followed by the sections between the reactor and the delta. Species richness for shrub and groundcover strata were also lowest in the delta. No endangered plant species were found. Three upland pine areas were also sampled. In support of K Reactor restart, this report summarizes a study of the wetland vegetation along Pen Branch. Reactor effluent enters Indian Grove Branch and then flows into Pen Branch and the Pen Branch Delta.

Advanced neutral gas diagnostics for magnetic confinement devices

International Nuclear Information System (INIS)

Wenzel, U.; Schlisio, G.; Marquardt, M.; Pedersen, T.S.; Kremeyer, T.; Schmitz, O.; Mackie, B.; Maisano-Brown, J.

2017-01-01

For the study of particle exhaust in nuclear fusion devices the neutral pressure must be measured in strong magnetic fields. We describe as an example the neutral pressure gauges in the Wendelstein 7-X stellarator. Two types are used: hot cathode ionization gauges (or ASDEX pressure gauges) and Penning gauges. We show some results from the first experimental campaign. The main problems were runtime effects and the failure of some ASDEX pressure gauges. To improve the reliability we integrated a new LaB 6 electron emitter into the ASDEX pressure gauges. In addition, a special Penning gauge without permanent magnets was developed in order to operate Penning gauges near the plasma edge. These new pressure gauges will be used in the upcoming campaign of Wendelstein 7-X.

Influence of geometry of the discharge interval on distribution of ion and electron streams at surface of the Penning source cathode

International Nuclear Information System (INIS)

Egiazaryan, G.A.; Khachatrian, Zh.B.; Badalyan, E.S.; Ter-Gevorgyan, E.I.; Hovhannisyan, V.N.

2006-01-01

In the discharge of oscillating electrons, the mechanism of the processes, which controls the distribution of the ion and electron streams over the cathode surface, is investigated experimentally. The influence of the length of the discharge interval on value and distribution of the ion and electron streams is analyzed. The distribution both of ion and electron streams at the cathode surface is determined at different conditions of the discharge. It is shown that for given values of the anode diameter d a =31 mm and the gas pressure P=5x10 -5 Torr, the intensive stream of positive ions falls entirely on the cathode central area in the whole interval of the anode length variation (l a =1-11 cm). At the cathode, the ion current reaches the maximal value at a certain (optimal) value of the anode length that, in turn, depends on the anode voltage U a . The intensive stream of longitudinal electrons forms in the short anodes only (l a =2.5-3.5 cm) and depending on the choice of the discharge regime, may fall both on central and middle parts of the cathode

Pen dosimeters

CERN Multimedia

SC/RP Group

2006-01-01

The Radiation Protection Group has decided to withdraw all pen dosimeters from the main PS and SPS access points. This will be effective as of January 2006. The following changes will be implemented: All persons working in a limited-stay controlled radiation area must wear an operational dosimeter in addition to their personal DIS dosimeter. Any persons not equipped with this additional dosimeter must contact the SC/RP Group, which will make this type of dosimeter available for temporary loan. A notice giving the phone numbers of the SC/RP Group members to contact will be displayed at the former distribution points for the pen dosimeters. Thank you for your cooperation. The SC/RP Group

Wave and transport studies utilizing dense plasma filaments generated with a lanthanum hexaboride cathode

International Nuclear Information System (INIS)

Van Compernolle, B.; Gekelman, W.; Pribyl, P.; Cooper, C. M.

2011-01-01

A portable lanthanum hexaboride (LaB 6 ) cathode has been developed for use in the LArge Plasma Device (LAPD) at UCLA. The LaB 6 cathode can be used as a tool for many different studies in experimental plasma physics. To date, the cathode has been used as a source of a plasma with a hot dense core for transport studies and diagnostics development, as a source of gradient driven modes, as a source of shear Alfven waves, and as a source of interacting current channels in reconnection experiments. The LaB 6 cathode is capable of higher discharge current densities than the main barium oxide coated LAPD cathode and is therefore able to produce plasmas of higher densities and higher electron temperatures. The 8.25 cm diameter cathode can be introduced into the LAPD at different axial locations without the need to break vacuum. The cathode can be scaled up or down for use as a portable secondary plasma source in other machines.

Cytotoxicity of Pd nanostructures supported on PEN: Influence of sterilization on Pd/PEN interface

Energy Technology Data Exchange (ETDEWEB)

Polívková, M., E-mail: polivkoa@vscht.cz [Department of Solid State Engineering, University of Chemistry and Technology Prague, 166 28 Prague (Czech Republic); Siegel, J. [Department of Solid State Engineering, University of Chemistry and Technology Prague, 166 28 Prague (Czech Republic); Rimpelová, S. [Department of Biochemistry and Microbiology, University of Chemistry and Technology Prague, 166 28 Prague (Czech Republic); Hubáček, T. [Institute of Hydrobiology, Biology Centre of the AS CR, 370 05 Ceske Budejovice (Czech Republic); Kolská, Z. [Materials Centre of Usti n. L., J.E. Purkyne University, 400 96 Usti nad Labem (Czech Republic); Švorčík, V. [Department of Solid State Engineering, University of Chemistry and Technology Prague, 166 28 Prague (Czech Republic)

2017-01-01

Non-conventional antimicrobial agents, such as palladium nanostructures, have been increasingly used in the medicinal technology. However, experiences uncovering their harmful and damaging effects to human health have begun to appear. In this study, we have focused on in vitro cytotoxicity assessment of Pd nanostructures supported on a biocompatible polymer. Pd nanolayers of variable thicknesses (ranging from 1.1 to 22.4 nm) were sputtered on polyethylene naphthalate (PEN). These nanolayers were transformed by low-temperature post-deposition annealing into discrete nanoislands. Samples were characterized by AFM, XPS, ICP-MS and electrokinetic analysis before and after annealing. Sterilization of samples prior to cytotoxicity testing was done by UV irradiation, autoclave and/or ethanol. Among the listed sterilization techniques, we have chosen the gentlest one which had minimal impact on sample morphology, Pd dissolution and overall Pd/PEN interface quality. Cytotoxic response of Pd nanostructures was determined by WST-1 cell viability assay in vitro using three model cell lines: mouse macrophages (RAW 264.7) and two types of mouse embryonic fibroblasts (L929 and NIH 3T3). Finally, cell morphology in response to Pd/PEN was evaluated by means of fluorescence microscopy. - Highlights: • Annealing of Pd nanolayers on PEN resulted to Pd aggregation and formation of discrete nanoislands. • UV treatment was found as the gentlest sterilization method in term of physicochemical properties of Pd/PEN interface. • Autoclaving and chemical sterilization by ethanol resulted into remarkable changes of Pd/PEN interface. • Cytotoxicity of Pd samples was insignificant. • Pd nanostructures are potentially applicable as health-unobjectionable antibacterial coatings of medical devices.

NovoPen Echo® insulin delivery device

Directory of Open Access Journals (Sweden)

Hyllested-Winge J

2016-01-01

Full Text Available Jacob Hyllested-Winge,1 Thomas Sparre,2 Line Kynemund Pedersen2 1Novo Nordisk Pharma Ltd, Tokyo, Japan; 2Novo Nordisk A/S, Søborg, Denmark Abstract: The introduction of insulin pen devices has provided easier, well-tolerated, and more convenient treatment regimens for patients with diabetes mellitus. When compared with vial and syringe regimens, insulin pens offer a greater clinical efficacy, improved quality of life, and increased dosing accuracy, particularly at low doses. The portable and discreet nature of pen devices reduces the burden on the patient, facilitates adherence, and subsequently contributes to the improvement in glycemic control. NovoPen Echo® is one of the latest members of the NovoPen® family that has been specifically designed for the pediatric population and is the first to combine half-unit increment (=0.5 U of insulin dosing with a simple memory function. The half-unit increment dosing amendments and accurate injection of 0.5 U of insulin are particularly beneficial for children (and insulin-sensitive adults/elders, who often require small insulin doses. The memory function can be used to record the time and amount of the last dose, reducing the fear of double dosing or missing a dose. The memory function also provides parents with extra confidence and security that their child is taking insulin at the correct doses and times. NovoPen Echo is a lightweight, durable insulin delivery pen; it is available in two different colors, which may help to distinguish between different types of insulin, providing more confidence for both users and caregivers. Studies have demonstrated a high level of patient satisfaction, with 80% of users preferring NovoPen Echo to other pediatric insulin pens. Keywords: NovoPen Echo®, memory function, half-unit increment dosing, adherence, children, adolescents 

From handwriting analysis to pen-computer applications

NARCIS (Netherlands)

Schomaker, L

1998-01-01

In this paper, pen computing, i.e. the use of computers and applications in which the pen is the main input device, will be described from four different viewpoints. Firstly a brief overview of the hardware developments in pen systems is given, leading to the conclusion that the technological

Impact of cathode evaporation on a free-burning arc

International Nuclear Information System (INIS)

Etemadi, K.

1990-01-01

In the center of a free-burning, high intensity argon arc at atmospheric pressure, a highly ionized vapor beam of copper has been generated by a continuous feeding of a thin (0.5 and 1 mm diameter) copper wire to the hot surface region of the cathode in the vicinity of the plasma attachment. The copper vapor is carried into the plasma column between the electrodes by the self-magnetic induced plasma flow caused by the conical shape of the cathode. In order to study the vapor beam, the arc is modeled at atmospheric pressure, with a current of 150 A, a gap spacing of 1 cm, a cathode tip of 60 degrees and a copper vapor flow of 1 mg/s. The temperature, mass flow, current flow and Cu concentration are calculated for the entire plasma region. The intensity distribution of CuI spectral line at 5218.2 angstrom is also recorded by emission spectroscopy and compared with the calculated values. The copper vapor in the cathode region has velocities of 210 m/s with a mass concentration of above 90% within 0.5 mm from the arc axis. The vapor passes from the cathode toward the anode with a slight diffusion in the argon plasma. Higher temperatures and current densities in the core of the arc, caused by the cathode evaporation, are calculated

Negative Ion Sources: Magnetron and Penning

CERN Document Server

Faircloth, D.C.

2013-12-16

The history of the magnetron and Penning electrode geometry is briefly outlined. Plasma generation by electrical discharge-driven electron impact ionization is described and the basic physics of plasma and electrodes relevant to magnetron and Penning discharges are explained. Negative ions and their applications are introduced, along with their production mechanisms. Caesium and surface production of negative ions are detailed. Technical details of how to build magnetron and Penning surface plasma sources are given, along with examples of specific sources from around the world. Failure modes are listed and lifetimes compared.

Negative Ion Sources: Magnetron and Penning

International Nuclear Information System (INIS)

Faircloth, D C

2013-01-01

The history of the magnetron and Penning electrode geometry is briefly outlined. Plasma generation by electrical discharge-driven electron impact ionization is described and the basic physics of plasma and electrodes relevant to magnetron and Penning discharges are explained. Negative ions and their applications are introduced, along with their production mechanisms. Caesium and surface production of negative ions are detailed. Technical details of how to build magnetron and Penning surface plasma sources are given, along with examples of specific sources from around the world. Failure modes are listed and lifetimes compared. (author)

Isodose plotting for pen plotters

International Nuclear Information System (INIS)

Rosen, I.I.

1985-01-01

A general algorithm for treatment plan isodose line plotting is described which is particularly useful for pen plotters. Unlike other methods of plotting isodose lines, this algorithm is designed specifically to reduce pen motion, thereby reducing plotting time and wear on the transport mechanism. Points with the desired dose value are extracted from the dose matrix and stored, sorted into continuous contours, and then plotted. This algorithm has been implemented on DEC PDP-11/60 and VAX-11/780 computers for use with two models of Houston Instrument pen plotters, two models of Tektronix vector graphics terminals, a DEC VT125 raster graphics terminal, and a DEC VS11 color raster graphics terminal. Its execution time is similar to simpler direct-plotting methods

The LongPen--the world's first original remote signing device.

Science.gov (United States)

Kruger, Diane M

2010-05-01

The LongPen is a remote-controlled pen and videoconferencing device conceived by Canadian author Margaret Atwood in 2004 and initially intended to bring "live" author signings to far away locations. The LongPen allows for individually inscribed long distance signatures and writing while maintaining an original record, written with pen and ink. LongPen specimens were compared with control specimens using different speeds, pen pressures, and types of pens. Preliminary indications are that LongPen inscriptions can be identified or associated with their author. Size and form are maintained and artifacts are subtle. Some limitations with respect to the capture of long tapered strokes, delicate connecting strokes, and differences in line width were noted. Factors which may impact forensic handwriting examinations include limited amounts of writing, light pen pressure, date of the writing, type of writing instrument, dimensions of the writing, and failure to consider that the device has been used.

Pen of Health Care Worker as Vector of Infection

Directory of Open Access Journals (Sweden)

Prashant Patil

2010-10-01

Full Text Available Nosocomial infections are the major concern in tertiary hospitals. Health care workers and their belonging are known to act as vector in transmission of infections. In present study, the writing pen of health care workers was worked out for carrying infection. The swab from writing pen of health care workers were cultured for any growth of microorganism and compared with swab from pen of the non health care workers. It was found that the rate of growth of microorganism were more in pen of health care workers. Similarly the organism attributed to the nosocomial infection was grown from the pens of health care workers. These organisms might be transmitted from the hands of health care workers. The writing pen which health care worker are using became the vectors of transmission of infection. So to prevent it, the most important way is to wash the hands and pen properly after examining the patients.

The effects of zonation of the pen and grouping in intact litters on use of pen, immune competence and health of pigs

DEFF Research Database (Denmark)

Damgaard, B.M.; Studnitz, M.; Nielsen, Jens

2006-01-01

The effects of pen design and group composition were examined with respect to activity, use of pen, floor conditions, health condition and immune competence for groups of 60 pigs. The experiment was designed with the two factors with zones/without zones and divided litters/intact litters....... The experiment included a total of 1440 pigs from weaning at the age of 4 weeks to the age of 18 weeks after weaning. In pens with zones, the selection of different areas for different activities was improved. Pens with zones were more dirty in the elimination and open areas than pens without zones. In pens...... with zones, the number of lymphocytes was decreased, the ability to respond to an additional challenge by a model infection was decreased and the number of neutrophils was increased in intact litters. In week 9, the health condition was better with a group composition consisting of intact litters compared...

Pen- Name in Persian and Arabic Poetry

Directory of Open Access Journals (Sweden)

Ebrahim Khodayar

2012-03-01

Full Text Available  Abstract Pen-name (Takhalloss is one of the main features of Persian poetry. It has been a matter of concern among many of Persian language geography poets in the orient at least up to the Mashrouteh era. Pen-name has been promoted among the other Muslim nations throuph Persian poetry. Although it is not as famous in the Arab nations as in the Persian speaking nations, it is known as “Alqab-o-shoara” among the Arab nations and, through this way, it has affected the poetrical wealth of the Arabic poets.   The Present paper, using description-analystic approach, compares the pen-names of Persian and Arabic poets under the title of “pen-names” and investigates their features in both cultures. The main research question is: What are the similarities and differences of poetic-names, in Persian and Arabic poets in terms of the type of name, position and importance? The results showed that Pseudonym by its amazing expansion in Persian poetry has also influenced Arabic poetry. In addition to the factors affecting in the choice of pen-names (like pseudonym, pen-name, nickname..., sometimes such external factors as events, commends, community benefactors and climate, as well as internal factors including the poets’ inner beliefs are associated too. .

Penning ionization processes studied by electron spectroscopy

International Nuclear Information System (INIS)

Yencha, A.J.

1978-01-01

The technique of measuring the kinetic energy of electrons ejected from atomic or molecular species as a result of collisional energy transfer between a metastable excited rare gas atom and an atom or molecule is known as Penning ionization spectroscopy. Like the analogous photoionization process of photoelectron spectroscopy, a considerable amount of information has been gained about the ionization potentials of numerous molecular systems. It is, in fact, through the combined analyses of photoelectron and Penning electron spectra that affords a probe of the particle-particle interactions that occur in the Penning process. In this paper a short survey of the phenomenon of Penning ionization, as studied by electron spectroscopy, will be presented as it pertains to the ionization processes of simple molecules by metastable excited atoms. (author)

Electrical shielding box measurement of the negative hydrogen beam from Penning ion gauge ion source.

Science.gov (United States)

Wang, T; Yang, Z; Dong, P; long, J D; He, X Z; Wang, X; Zhang, K Z; Zhang, L W

2012-06-01

The cold-cathode Penning ion gauge (PIG) type ion source has been used for generation of negative hydrogen (H(-)) ions as the internal ion source of a compact cyclotron. A novel method called electrical shielding box dc beam measurement is described in this paper, and the beam intensity was measured under dc extraction inside an electrical shielding box. The results of the trajectory simulation and dc H(-) beam extraction measurement were presented. The effect of gas flow rate, magnetic field strength, arc current, and extraction voltage were also discussed. In conclusion, the dc H(-) beam current of about 4 mA from the PIG ion source with the puller voltage of 40 kV and arc current of 1.31 A was extrapolated from the measurement at low extraction dc voltages.

De innemende verteller Louwrens Penning

OpenAIRE

Ester, Hans

2012-01-01

Dutch author Louwrens Penning (1854 – 1927) indisputably contributed more than any other novelist in the Netherlands to the high degree of solidarity with the Boers before, during and after the Anglo- Boer War 1899 – 1902. Penning, being a believer in the Calvinist tradition, had a profound trust in God’s guidance of history. He identified the war of the Boer soldiers against the British imperialists with the rebellion of the Dutch out of their true religious convictions against t...

Improved Cathode Structure for a Direct Methanol Fuel Cell

Science.gov (United States)

Valdez, Thomas; Narayanan, Sekharipuram

2005-01-01

An improved cathode structure on a membrane/electrode assembly has been developed for a direct methanol fuel cell, in a continuing effort to realize practical power systems containing such fuel cells. This cathode structure is intended particularly to afford better cell performance at a low airflow rate. A membrane/electrode assembly of the type for which the improved cathode structure was developed (see Figure 1) is fabricated in a process that includes brush painting and spray coating of catalyst layers onto a polymer-electrolyte membrane and onto gas-diffusion backings that also act as current collectors. The aforementioned layers are then dried and hot-pressed together. When completed, the membrane/electrode assembly contains (1) an anode containing a fine metal black of Pt/Ru alloy, (2) a membrane made of Nafion 117 or equivalent (a perfluorosulfonic acid-based hydrophilic, proton-conducting ion-exchange polymer), (3) a cathode structure (in the present case, the improved cathode structure described below), and (4) the electrically conductive gas-diffusion backing layers, which are made of Toray 060(TradeMark)(or equivalent) carbon paper containing between 5 and 6 weight percent of poly(tetrafluoroethylene). The need for an improved cathode structure arises for the following reasons: In the design and operation of a fuel-cell power system, the airflow rate is a critical parameter that determines the overall efficiency, cell voltage, and power density. It is desirable to operate at a low airflow rate in order to obtain thermal and water balance and to minimize the size and mass of the system. The performances of membrane/electrode assemblies of prior design are limited at low airflow rates. Methanol crossover increases the required airflow rate. Hence, one way to reduce the required airflow rate is to reduce the effect of methanol crossover. Improvement of the cathode structure - in particular, addition of hydrophobic particles to the cathode - has been

9 CFR 313.1 - Livestock pens, driveways and ramps.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Livestock pens, driveways and ramps... INSPECTION AND CERTIFICATION HUMANE SLAUGHTER OF LIVESTOCK § 313.1 Livestock pens, driveways and ramps. (a) Livestock pens, driveways and ramps shall be maintained in good repair. They shall be free from sharp or...

Coherent states approach to Penning trap

International Nuclear Information System (INIS)

Fernandez, David J; Velazquez, Mercedes

2009-01-01

By using a matrix technique, which allows us to identify directly the ladder operators, the Penning trap coherent states are derived as eigenstates of the appropriate annihilation operators. These states are compared with those obtained through the displacement operator. The associated wavefunctions and mean values for some relevant operators in these states are also evaluated. It turns out that the Penning trap coherent states minimize the Heisenberg uncertainty relation

Administration technique and storage of disposable insulin pens reported by patients with diabetes.

Science.gov (United States)

Mitchell, Virginia D; Porter, Kyle; Beatty, Stuart J

2012-01-01

The purpose of the study was to evaluate insulin injection technique and storage of insulin pens as reported by patients with diabetes and to compare correct pen use to initial education on injection technique, hemoglobin A1C, duration of insulin therapy, and duration of insulin pen. Cross-sectional questionnaire orally administered to patients at a university-affiliated primary care practice. Subjects were patients with diabetes who were 18 years or older and prescribed a disposable insulin pen for at least 4 weeks. A correct usage score was calculated for each patient based on manufacturer recommendations for disposable insulin pen use. Associations were made between the correct usage score and certainty in technique, initial education, years of insulin therapy, duration of pen use, and hemoglobin A1C. Sixty-seven patients completed the questionnaire, reporting total use of 94 insulin pens. The 3 components most often neglected by patients were priming pen needle, holding for specific count time before withdrawal of pen needle from skin, and storing an in-use pen. For three-fourths of the insulin pens being used, users did not follow the manufacturer's instructions for proper administration and storage of insulin pens. Correct usage scores were significantly higher if initial education on insulin pens was performed by a pharmacist or nurse. The majority of patients may be ignoring or unaware of key components for consistent insulin dosing using disposable insulin pens; therefore, initial education and reeducation on correct use of disposable insulin pens by health care professionals are needed.

Pen-and-Paper User Interfaces

CERN Document Server

Steimle, Jurgen

2012-01-01

Even at the beginning of the 21st century, we are far from becoming paperless. Pen and paper is still the only truly ubiquitous information processing technology. Pen-and-paper user interfaces bridge the gap between paper and the digital world. Rather than replacing paper with electronic media, they seamlessly integrate both worlds in a hybrid user interface. Classical paper documents become interactive. This opens up a huge field of novel computer applications at our workplaces and in our homes. This book provides readers with a broad and extensive overview of the field, so as to provide a fu

Early warning of diarrhea and pen fouling in growing pigs using sensor-based monitoring

DEFF Research Database (Denmark)

Jensen, D. B.; Toft, Nils; Kristensen, A. R.

2016-01-01

then identify specific pens in need of extra attention. Here we evaluate the value of monitoring live weight, feed usage, humidity, drinking behavior and pen temperature in relation to early warnings of diarrhea and pen fouling in slaughter pigs. Materials and methods: We used data collected in 16 pens (8...... double-pens) between November 2013 and December 2014 at a commercial Danish farm. During this time, three new batches were inserted. We monitored the mean live weight of the pigs per pen (weekly, only in 4 pens), feed usage per double-pen (daily), humidity per section (daily), temperature at two...... positions per pen (hourly), water flow per double-pen (liters/hour/pig) and drinking frequency per pen (activations/hour/pig). Staff registrations of diarrhea and pen fouling were the events of interest. The data were divided into a learning set (15 events) and a test set (18 events). The data were modeled...

Tail posture predicts tail biting outbreaks at pen level in weaner pigs

DEFF Research Database (Denmark)

Lahrmann, Helle Pelant; Hansen, Christian Fink; D'Eath, Rick

2018-01-01

posture and behaviour could be detected at pen level between upcoming tail biting pens (T-pens) and control pens (C-pens). The study included 2301 undocked weaner pigs in 74 pens (mean 31.1 pigs/pen; SD 1.5). Tails were scored three times weekly (wound freshness, wound severity and tail length) between 07......Detecting a tail biting outbreak early is essential to reduce the risk of pigs getting severe tail damage. A few previous studies suggest that tail posture and behavioural differences can predict an upcoming outbreak. The aim of the present study was therefore to investigate if differences in tail......:00 h-14:00 h from weaning until a tail biting outbreak. An outbreak (day 0) occurred when at least four pigs had a tail damage, regardless of wound freshness. On average 7.6 (SD 4.3) pigs had a damaged tail (scratches + wound) in T-pens on day 0. Tail posture and behaviour (activity, eating...

Humalog(®) KwikPen™: an insulin-injecting pen designed for ease of use.

Science.gov (United States)

Schwartz, Sherwyn L; Ignaut, Debra A; Bodie, Jennifer N

2010-11-01

Insulin pens offer significant benefits over vial and syringe injections for patients with diabetes who require insulin therapy. Insulin pens are more discreet, easier for patients to hold and inject, and provide better dosing accuracy than vial and syringe injections. The Humalog(®) KwikPen™ (prefilled insulin lispro [Humalog] pen, Eli Lilly and Company, Indianapolis, IN, USA) is a prefilled insulin pen highly rated by patients for ease of use in injections, and has been preferred by patients to both a comparable insulin pen and to vial and syringe injections in comparator studies. Together with an engineering study demonstrating smoother injections and reduced dosing error versus a comparator pen, recent evidence demonstrates the Humalog KwikPen device is an accurate, easy-to-use, patient-preferred insulin pen.

Small size neutron tube UNG-1

International Nuclear Information System (INIS)

Bespalov, D.F.; Mints, A.Z.; Shkol'nikov, A.S.

A tube UNG-1 (universal neutron gas-filled) is designed for the use in the well neutron generators IGN-1 and IGN-1-M (a pulse neutron generator). Their serial production in the USSR has been started in 1963. At the same year, the serial production of the tubes UNG-1 has been started. Thus, this tube is the first serial logging accelerating tube in the USSR. A Penning source, equipped with a hot cathode, was selected as an ion source of the tube

Of Papers and Pens: Polysemes and Homophones in Lexical (Mis)Selection

Science.gov (United States)

Li, Leon; Slevc, L. Robert

2017-01-01

Every word signifies multiple senses. Many studies using comprehension-based measures suggest that polysemes' senses (e.g., "paper" as in "printer paper" or "term paper") share lexical representations, whereas homophones' meanings (e.g., "pen" as in "ballpoint pen" or "pig pen")…

Understanding anode and cathode behaviour in high-pressure discharge lamps

Science.gov (United States)

Flesch, P.; Neiger, M.

2005-09-01

High-intensity discharge (HID) lamps have widespread and modern areas of application including general lighting, video/movie projection (e.g. UHP lamp), street/industrial lighting, and automotive headlight lamps (D2/xenon lamp). Even though HID lamps have been known for several decades now, the important plasma-electrode interactions are still not well understood. Because HID lamps are usually operated on ac (electrodes switch alternately from anode to cathode phase), time-dependent simulations including realistic and verified anode and cathode models are essential. Therefore, a recently published investigation of external laser heating of an electrode during anode and cathode phase in an operating HID lamp [28] provided the basis for our present paper. These measurements revealed impressive influences of the external laser heating on electrode fall voltage and electrode temperature. Fortunately, the effects are very different during anode and cathode phase. Thus, by comparing the experimental findings with results from our numerical simulations we can learn much about the principles of electrode behaviour and explain in detail the differences between anode and cathode phase. Furthermore, we can verify our model (which includes plasma column, hot plasma spots in front of the electrodes, constriction zones and near-electrode non-local thermal equilibrium-plasma as well as anode and cathode) that accounts for all relevant physical processes concerning plasma, electrodes and interactions between them. Moreover, we investigate the influence of two different notions concerning ionization and recombination in the near electrode plasma on the numerical results. This improves our physical understanding of near-electrode plasma likewise and further increases the confidence in the model under consideration. These results are important for the understanding and the further development of HID lamps which, due to their small dimensions, are often experimentally inaccessible

Essential Characteristics of Plasma Antennas Filled with He-Ar Penning Gases

International Nuclear Information System (INIS)

Sun Naifeng; Li Wenzhong; Wang Shiqing; Li Jian; Ci Jiaxiang

2012-01-01

Based on the essential theory of Penning gases, the discharge characteristics of He-Ar Penning gases in insulating tubes were analyzed qualitatively. The relation between the effective length of an antenna column filled with He-Ar Penning gases and the applied radio frequency (RF) power was investigated both theoretically and experimentally. The distribution of the plasma density along the antenna column in different conditions was studied. The receiving characteristics of local frequency modulated (FM) electromagnetic waves by the plasma antenna filled with He-Ar Penning gases were compared with those by an aluminum antenna with the same dimensions. Results show that it is feasible to take plasma antennas filled with He-Ar Penning gases as receiving antennas.

Ease of use and patient preference injection simulation study comparing two prefilled insulin pens.

Science.gov (United States)

Clark, Paula E; Valentine, Virginia; Bodie, Jennifer N; Sarwat, Samiha

2010-07-01

To determine patient ease of use and preference for the Humalog KwikPen* (prefilled insulin lispro [Humalog dagger] pen, Eli Lilly and Company, Indianapolis, IN, USA) (insulin lispro pen) versus the Next Generation FlexPen double dagger (prefilled insulin aspart [NovoRapid section sign ] pen, Novo Nordisk A/S, Bagsvaerd, Denmark) (insulin aspart pen). This was a randomized, open-label, 2-period, 8-sequence crossover study in insulin pen-naïve patients with diabetes. Randomized patients (N = 367) received device training, then simulated low- (15 U) and high- (60 U) dose insulin injections with an appliance. Patients rated pens using an ease of use questionnaire and were asked separately for final pen preferences. The Insulin Device 'Ease of Use' Battery is a 10-item questionnaire with a 7-point scale (higher scores reflect greater ease of use). The primary objective was to determine pen preference for 'easy to press to inject my dose' (by comparing composite scores [low- plus high-dose]). Secondary objectives were to determine pen preference on select questionnaire items (from composite scores), final pen preference, and summary responses for all questionnaire items. On the primary endpoint, 'easy to press to inject my dose,' a statistically significant majority of patients with a preference chose the insulin lispro pen over the insulin aspart pen (68.4%, 95% CI = 62.7-73.6%). Statistically significant majorities of patients with a preference also favored the insulin lispro pen on secondary items: 'easy to hold in my hand when I inject' (64.9%, 95% CI = 58.8-70.7%), 'easy to use when I am in a public place' (67.5%, 95% CI = 61.0-73.6%), and 'overall easy to use' (69.9%, 95% CI = 63.9-75.4%). A statistically significant majority of patients had a final preference for the insulin lispro pen (67.3%, 95% CI = 62.2-72.1%). Among pen-naïve patients with diabetes who had a preference, the majority preferred the insulin lispro pen over the insulin aspart pen with regard

Performance evaluation of an open-cathode PEM fuel cell stack under ambient conditions: Case study of United Arab Emirates

International Nuclear Information System (INIS)

Al-Zeyoudi, Hend; Sasmito, Agus P.; Shamim, Tariq

2015-01-01

Highlights: • Performance evaluation of open-cathode PEM fuel cell stacks with forced air-convection. • Stack performance can vary up to 40% from winter to summer. • Hot and arid condition leads to membrane drying and performance deterioration. • Anode humidification improves the stack performance up to 40% during summer. - Abstract: The open-cathode polymer electrolyte membrane (PEM) fuel cell stack has been a promising candidate as a sustainable energy conversion system for replacing fossil fuel-based energy conversion devices in portable and automotive applications. As the ambient air is directly used to provide both oxidant and cooling, the complex cooling loop can be avoided which reduces the complexity and cost. However, the stack performance is highly affected by ambient conditions, i.e., ambient temperature and humidity. In this study, the effect of monthly ambient air conditions (temperature and humidity) is evaluated with respect to the stack’s power production performance as well as thermal, water and gas management by employing a validated three-dimensional open-cathode PEM fuel cell stack model. The annual climate data from the hot and arid environment of Abu Dhabi, United Arab Emirates (UAE) are used as a case study. The objective is to develop a better fundamental understanding of the interactions of physical phenomena in a fuel cell stack, which can assist in improving the performance and operation of an open-cathode PEM fuel cell-powered vehicle. The results indicate that the stack performance can vary significantly (up to 40%) from winter to summer, especially at high operating currents, with significant changes in the stack temperature and the water content at the membrane. Moreover, the anode humidification results in a significant improvement in the stack performance (up to 40%) in hot and dry conditions. However, a careful balance has to be struck between the humidifier parasitic load and the stack power.

Pen-based Interfaces for Engineering and Education

Science.gov (United States)

Stahovich, Thomas F.

Sketches are an important problem-solving tool in many fields. This is particularly true of engineering design, where sketches facilitate creativity by providing an efficient medium for expressing ideas. However, despite the importance of sketches in engineering practice, current engineering software still relies on traditional mouse and keyboard interfaces, with little or no capabilities to handle free-form sketch input. With recent advances in machine-interpretation techniques, it is now becoming possible to create practical interpretation-based interfaces for such software. In this chapter, we report on our efforts to create interpretation techniques to enable pen-based engineering applications. We describe work on two fundamental sketch understanding problems. The first is sketch parsing, the task of clustering pen strokes or geometric primitives into individual symbols. The second is symbol recognition, the task of classifying symbols once they have been located by a parser. We have used the techniques that we have developed to construct several pen-based engineering analysis tools. These are used here as examples to illustrate our methods. We have also begun to use our techniques to create pen-based tutoring systems that scaffold students in solving problems in the same way they would ordinarily solve them with paper and pencil. The chapter concludes with a brief discussion of these systems.

The LEBIT 9.4 T Penning trap system

Energy Technology Data Exchange (ETDEWEB)

Ringle, R.; Bollen, G.; Schury, P.; Sun, T. [National Superconducting Cyclotron Laboratory, East Lansing, MI (United States); Michigan State University, Department of Physics and Astronomy, East Lansing, MI (United States); Lawton, D.; Schwarz, S. [National Superconducting Cyclotron Laboratory, East Lansing, MI (United States)

2005-09-01

The initial experimental program with the Low-Energy Beam and Ion Trap Facility, or LEBIT, will concentrate on Penning trap mass measurements of rare isotopes, delivered by the Coupled Cyclotron Facility (CCF) of the NSCL. The LEBIT Penning trap system has been optimized for high-accuracy mass measurements of very short-lived isotopes. (orig.)

The LEBIT 9.4 T Penning trap system

International Nuclear Information System (INIS)

Ringle, R.; Bollen, G.; Schury, P.; Sun, T.; Lawton, D.; Schwarz, S.

2005-01-01

The initial experimental program with the Low-Energy Beam and Ion Trap Facility, or LEBIT, will concentrate on Penning trap mass measurements of rare isotopes, delivered by the Coupled Cyclotron Facility (CCF) of the NSCL. The LEBIT Penning trap system has been optimized for high-accuracy mass measurements of very short-lived isotopes. (orig.)

Improving lithium-ion battery performances by adding fly ash from coal combustion on cathode film

Energy Technology Data Exchange (ETDEWEB)

Dyartanti, Endah Retno; Jumari, Arif, E-mail: arifjumari@yahoo.com; Nur, Adrian; Purwanto, Agus [Research Group of Battery & Advanced Material, Department of Chemical Engineering, Sebelas Maret University, Jl. Ir. Sutami 36 A Kentingan, Surakarta Indonesia 57126 (Indonesia)

2016-02-08

A lithium battery is composed of anode, cathode and a separator. The performance of lithium battery is also influenced by the conductive material of cathode film. In this research, the use of fly ash from coal combustion as conductive enhancer for increasing the performances of lithium battery was investigated. Lithium iron phosphate (LiFePO{sub 4}) was used as the active material of cathode. The dry fly ash passed through 200 mesh screen, LiFePO{sub 4} and acethylene black (AB), polyvinylidene fluoride (PVDF) as a binder and N-methyl-2-pyrrolidone (NMP) as a solvent were mixed to form slurry. The slurry was then coated, dried and hot pressed to obtain the cathode film. The ratio of fly ash and AB were varied at the values of 1%, 2%, 3%, 4% and 5% while the other components were at constant. The anode film was casted with certain thickness and composition. The performance of battery lithium was examined by Eight Channel Battery Analyzer, the composition of the cathode film was examined by XRD (X-Ray Diffraction), and the structure and morphology of the anode film was analyzed by SEM (Scanning Electron Microscope). The composition, structure and morphology of cathode film was only different when fly ash added was 4% of AB or more. The addition of 2% of AB on cathode film gave the best performance of 81.712 mAh/g on charging and 79.412 mAh/g on discharging.

Applications of Cold Cathode PIG Ion Source in Lithography

International Nuclear Information System (INIS)

Bassal, N.I.

2012-01-01

The cold cathode Penning ion source (PIG) of axial type could be modified to produce ion and electron beam with a considerable amount to use it in the lithography process. Lithography is a new applications of ion/electron beam at which one can use the ion/ or electron beam as a pencil to write and draw on a metal surface. The electron beam takes 1/3 the time needed for ion beam to make good picture. So that with the help of ion/or electron beam lithography one can mark tools, parts, instruments, and equipment with names, numbers, designs, trademark or brand name in few seconds. It is an easy process, quick and an inexpensive method. Firstly, operating characteristics of this ion source is studied. Lithography application of ion source with optimum conditions is done. Later, the hardness and the tensile strength is measured and each of them increases with increasing time

A very high yield electron impact ion source for analytical mass spectrometry

International Nuclear Information System (INIS)

Koontz, S.L.; Bonner Denton, M.

1981-01-01

A novel ion source designed for use in mass spectrometric determination of organic compounds is described. The source is designed around a low pressure, large volume, hot cathode Penning discharge. The source operates in the 10 -4 - 10 -7 torr pressure domain and is capable of producing focusable current densities several orders of magnitude greater than those produced by conventional Nier -type sources. Mass spectra of n-butane and octafluoro-2-butene are presented. An improved signal-to-noise ratio is demonstrated with a General Electric Monopole 300 mass spectrometer. (orig.)

Correlates of cannabis vape-pen use and knowledge among U.S. college students

Directory of Open Access Journals (Sweden)

Tessa Frohe

2018-06-01

Full Text Available Introduction: The proliferation of electronic devices, such as vape-pens, has provided alternative means for cannabis use. Research has found cannabis-vaping (i.e., vape-pen use is associated with lower perceived risks and higher cannabis use. Knowledge of these products may increase likelihood of subsequent use. As policies for cannabis shift, beliefs that peers and family approve of this substance use (injunctive norms increase and there has been an increase in vape-pen use among young adults (18–35year olds; however, correlates thereof remain unknown. Young adults often engage in cross-substance use with cannabis and alcohol, making alcohol a potential correlate of cannabis vape-pen use and knowledge. Therefore, we examined alcohol use and other potential correlates of vape-pen use and knowledge among a sample of university students. Methods: This secondary data analysis utilized surveys at multiple colleges in the U.S. (N=270. Alcohol use, social anxiety, cannabis expectancies, injunctive and descriptive norms and facets of impulsivity were examined as correlates of vape-pen use and knowledge using bivariate correlations and logistic regressions. Results: Alcohol use was correlated with cannabis vape-pen use and knowledge. Frequency of cannabis use, peer injunctive norms, and positive expectancies were associated with increased likelihood of vape-pen use. Lack of premeditation, a facet of impulsivity, was associated with cannabis vape-pen knowledge. Conclusions: Given the unknown nature and consequences of cannabis vape-pens, the present findings offer valuable information on correlates of this behavior. Further, correlates of knowledge of vape-pens may point to areas for education and clinical intervention to prevent heavy cannabis vape-pen use. Keywords: Marijuana, Vaporizer, College students, Substance use, Attitudes, Cannabis

Interelectrode plasma evolution in a hot refractory anode vacuum arc: Theory and comparison with experiment

International Nuclear Information System (INIS)

Beilis, I.I.; Goldsmith, S.; Boxman, R.L.

2002-01-01

In this paper a theoretical study of a hot refractory anode vacuum arc, which was previously investigated experimentally [Phys. Plasmas 7, 3068 (2000)], is presented. The arc was sustained between a thermally isolated refractory anode and a water-cooled copper cathode. The arc started as a multicathode-spot (MCS) vacuum arc and then switched to the hot refractory anode vacuum arc (HRAVA) mode. In the MCS mode, the cathodic plasma jet deposits a film of the cathode material on the anode. Simultaneously, the temperature of the thermally isolated anode begins to rise, reaching eventually a sufficiently high temperature to re-evaporate the deposited material, which is subsequently ionized in the interelectrode gap. The transition to the HRAVA mode is completed when the density of the interelectrode plasma consists mostly of ionized re-evaporated atoms--the anode plasma. The evolution of the HRAVA mode is characterized by the propagation of a luminous plasma plume from the anode to the cathode. The time dependent model of the various physical processes taking place during the transition to the HRAVA mode is represented by a system of equations describing atom re-evaporation, atom ionization through the interaction of the cathode jet and the interelectrode plasma with the anode vapor, plasma plume propagation, plasma radial expansion, plasma energy, and heavy particle density balance. The time dependence of the anode heat flux and the effective anode voltage were obtained by solving these equations. In addition, the time dependent plasma electron temperature, plasma density, anode potential drop, arc voltage, and anode temperature distribution were calculated and compared with previous measurements. It was shown that the observed decrease of the effective anode voltage with time during the mode transition is due to decrease of the heat flux incident on the anode surface from the cathode spot jets

Microscopic characterizations of membrane electrode assemblies prepared under different hot-pressing conditions

International Nuclear Information System (INIS)

Liang, Z.X.; Zhao, T.S.; Xu, C.; Xu, J.B.

2007-01-01

The durability of the membrane electrode assembly (MEA) for direct methanol fuel cells (DMFCs) is one of the most critical issues to be addressed before widespread commercialization of the DMFC technology. In this work, we investigated the effect of the hot-pressing duration on the performance and durability of the MEA prepared by hot-pressing technique. It was found that the 60-min hot pressing at 135 deg. C under the pressure of 4.0 MPa yielded a significantly improved MEA durability than did the 3-min hot pressing (a typical duration in practice) under the same condition, but no substantial difference was found in the cell performance of the MEAs prepared with the two different hot-pressing durations. The reason why the hot-pressing duration had no significant effect on cell performance is explained based on X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and Fourier transform infrared spectroscopy (FT-IR) characterizations of the changes in the physiochemical properties of MEAs and their constituent components, including the anode, cathode and Nafion membrane, before and after hot pressing with different durations

Tilting-Twisting-Rolling: a pen-based technique for compass geometric construction

Institute of Scientific and Technical Information of China (English)

Fei LYU; Feng TIAN; Guozhong DAI; Hongan WANG

2017-01-01

This paper presents a new pen-based technique,Tilting-Twisting-Rolling,to support compass geometric construction.By leveraging the 3D orientation information and 3D rotation information of a pen,this technique allows smooth pen action to complete multi-step geometric construction without switching task states.Results from a user study show this Tilting-Twisting-Rolling technique can improve user performance and user experience in compass geometric construction.

Particle confinement in penning traps an introduction

CERN Document Server

Vogel, Manuel

2018-01-01

This book provides an introduction to the field of Penning traps and related experimental techniques. It serves both as a primer for those entering the field, and as a quick reference for those working in it. The book is motivated by the observation that often a vast number of different resources have to be explored to gain a good overview of Penning trap principles. This is especially true for students who experience additional difficulty due to the different styles of presentation and notation. This volume provides a broad introductory overview in unified notation.

Penning transfer in argon-based gas mixtures

CERN Document Server

Sahin, O; Tapan, I; Ozmutlu, E N

2010-01-01

Penning transfers, a group of processes by which excitation energy is used to ionise the gas, increase the gas gain in some detectors. Both the probability that such transfers occur and the mechanism by which the transfer takes place, vary with the gas composition and pressure. With a view to developing a microscopic electron transport model that takes Penning transfers into account, we use this dependence to identify the transfer mechanisms at play. We do this for a number of argon-based gas mixtures, using gain curves from the literature.

Analysis of cathode geometry to minimize cathode erosion in direct current microplasma jet

Energy Technology Data Exchange (ETDEWEB)

Causa, Federica [Dipartimento di Scienze dell' Ambiente, della Sicurezza, del Territorio, degli Alimenti e della Salute, Universita degli studi di Messina, 98122 Messina (Italy); Ghezzi, Francesco; Caniello, Roberto; Grosso, Giovanni [Istituto di Fisica del Plasma, Consiglio Nazionale delle Ricerche, EURATOM-ENEA-CNR Association, Via R. Cozzi 53, 20125 Milano (Italy); Dellasega, David [Istituto di Fisica del Plasma, Consiglio Nazionale delle Ricerche, EURATOM-ENEA-CNR Association, Via R. Cozzi 53, 20125 Milano (Italy); Dipartimento di Energia, Politecnico di Milano, Via Ponzio 34/3, 20133 Milano (Italy)

2012-12-15

Microplasma jets are now widely used for deposition, etching, and materials processing. The present study focuses on the investigation of the influence of cathode geometry on deposition quality, for microplasma jet deposition systems in low vacuum. The interest here is understanding the influence of hydrogen on sputtering and/or evaporation of the electrodes. Samples obtained with two cathode geometries with tapered and rectangular cross-sections have been investigated experimentally by scanning electron microscopy and energy dispersion X-ray spectroscopy. Samples obtained with a tapered-geometry cathode present heavy contamination, demonstrating cathode erosion, while samples obtained with a rectangular-cross-section cathode are free from contamination. These experimental characteristics were explained by modelling results showing a larger radial component of the electric field at the cathode inner wall of the tapered cathode. As a result, ion acceleration is larger, explaining the observed cathode erosion in this case. Results from the present investigation also show that the ratio of radial to axial field components is larger for the rectangular geometry case, thus, qualitatively explaining the presence of micro-hollow cathode discharge over a wide range of currents observed in this case. In the light of the above findings, the rectangular cathode geometry is considered to be more effective to achieve cleaner deposition.

Fabrication of sacrificial anode cathodic protection through casting method

International Nuclear Information System (INIS)

Mohd Sharif Sattar; Muhamad Daud; Siti Radiah Mohd Kamarudin; Azali Muhamad; Zaiton Selamat; Rusni Rejab

2007-01-01

Aluminum is one of the few metals that can be cast by all of the processes used in casting metals. These processes consist of die casting, permanent mold casting, sand casting (green sand and dry sand), plaster casting, investment casting, and continuous casting. Other processes such as lost foam, squeeze casting, and hot isostatic pressing are also used. Permanent mold casting method was selected in which used for fabricating of sacrificial anode cathodic protection. This product was ground for surface finished and fabricated in the cylindrical form and reinforced with carbon steel at a center of the anode. (Author)

Operation of cold-cathode gauges in high magnetic fields

International Nuclear Information System (INIS)

Thomas, S.R. Jr.; Goerz, D.A.; Pickles, W.L.

1985-01-01

The Mirror Fusion Test Facility (MFTF-B), under construction at LLNL, requires measurement of the neutral gas density in high magnetic fields near the plasma at several axial regions. This Background Gas Pressure (BGP) diagnostic will help us understand the role of background neutrals in particle and power balance, particularly in the maintenance of the cold halo plasma that shields the hot core plasma from the returning neutrals. It consists of several cold-cathode, magnetron-type gauges stripped of their permanent magnets, and utilizes the MFTF-B ambient B-field in strengths of 5 to 25 kG. Similar gauges have operated in TMX-U in B-fields up to 3 kG. To determine how well the gauges will perform, we assembled a test stand which operated magnetron gauges in an external, uniform magnetic field of up to 30 kG, over a pressure range of 1E-8 T to 1E-5 T, at several cathode voltages. This paper describes the test stand and presents the results of the tests

Depression cathode structure for cathode ray tubes having surface smoothness and method for producing same

International Nuclear Information System (INIS)

Rychlewski, T.V.

1984-01-01

Depression cathode structures for cathode ray tubes are produced by dispensing liquid cathode material into the depression of a metallic supporting substrate, removing excess cathode material by passing a doctor blade across the substrate surface and over the depression, and drying the cathode layer to a substantially immobile state. The cathode layer may optionally be further shaped prior to substantially complete drying thereof

Asymmetric Penning trap coherent states

International Nuclear Information System (INIS)

Contreras-Astorga, Alonso; Fernandez, David J.

2010-01-01

By using a matrix technique, which allows to identify directly the ladder operators, the coherent states of the asymmetric Penning trap are derived as eigenstates of the appropriate annihilation operators. They are compared with those obtained through the displacement operator method.

RESEARCHES REGARDING THE MAIN REPRODUCTION INDICATORS DETERMINATED IN SOWS, STAND GESTATION PEN TIPE

Directory of Open Access Journals (Sweden)

RAMONA UNTARU

2007-05-01

Full Text Available Current researches were carried out with the goal to quantisize the lost from the weaning to early gestation at the sows housed in open pen gestation. In this trail we tested two pen types, different not only by size, but also by feeders’ emplacement. The main reproduction indicators that we calculated until the 28 gestation day were the proportion of sows in heat after weaning, the weaning to estrus interval and the gestation rates. The weaning to estrus interval was about 4 to 7 days, most sows were in heat in the day 5 and 6 days after weaning. The percent of heat detection after weaning was 71.42% for the small pens and 70.71% for the big pens (differences statistically non significant, chi test value was 0.983. The gestation rate at 28 days after insemination was 91.62% for the small pens and 94.72% for the large pens (chi test value 0,959, statistically non significant differences. The overpopulation for heat induction and after that chipping animals together in those pens, show that the lost are up to 40.47%, between weaning – day 28 of gestation.

Dynamic-compliance and viscosity of PET and PEN

International Nuclear Information System (INIS)

Weick, Brian L.

2016-01-01

Complex dynamic-compliance and in-phase dynamic-viscosity data are presented and analyzed for PET and PEN advanced polyester substrates used for magnetic tapes. Frequency-temperature superposition is used to predict long-term behavior. Temperature and frequency ranges for the primary glass transition and secondary transitions are discussed and compared for PET and PEN. Shift factors from frequency-temperature superposition are used to determine activation energies for the transitions, and WLF parameters are determined for the polyester substrates.

Dynamic-compliance and viscosity of PET and PEN

Energy Technology Data Exchange (ETDEWEB)

Weick, Brian L. [School of Engineering and Computer Science, University of the Pacific, Stockton, California, 95211 (United States)

2016-05-18

Complex dynamic-compliance and in-phase dynamic-viscosity data are presented and analyzed for PET and PEN advanced polyester substrates used for magnetic tapes. Frequency-temperature superposition is used to predict long-term behavior. Temperature and frequency ranges for the primary glass transition and secondary transitions are discussed and compared for PET and PEN. Shift factors from frequency-temperature superposition are used to determine activation energies for the transitions, and WLF parameters are determined for the polyester substrates.

Dynamic-compliance and viscosity of PET and PEN

Science.gov (United States)

Weick, Brian L.

2016-05-01

Complex dynamic-compliance and in-phase dynamic-viscosity data are presented and analyzed for PET and PEN advanced polyester substrates used for magnetic tapes. Frequency-temperature superposition is used to predict long-term behavior. Temperature and frequency ranges for the primary glass transition and secondary transitions are discussed and compared for PET and PEN. Shift factors from frequency-temperature superposition are used to determine activation energies for the transitions, and WLF parameters are determined for the polyester substrates.

Space-charge effects in Penning ion traps

Science.gov (United States)

Porobić, T.; Beck, M.; Breitenfeldt, M.; Couratin, C.; Finlay, P.; Knecht, A.; Fabian, X.; Friedag, P.; Fléchard, X.; Liénard, E.; Ban, G.; Zákoucký, D.; Soti, G.; Van Gorp, S.; Weinheimer, Ch.; Wursten, E.; Severijns, N.

2015-06-01

The influence of space-charge on ion cyclotron resonances and magnetron eigenfrequency in a gas-filled Penning ion trap has been investigated. Off-line measurements with K39+ using the cooling trap of the WITCH retardation spectrometer-based setup at ISOLDE/CERN were performed. Experimental ion cyclotron resonances were compared with ab initio Coulomb simulations and found to be in agreement. As an important systematic effect of the WITCH experiment, the magnetron eigenfrequency of the ion cloud was studied under increasing space-charge conditions. Finally, the helium buffer gas pressure in the Penning trap was determined by comparing experimental cooling rates with simulations.

Effect of shade on animal welfare, growth performance, and carcass characteristics in large pens of beef cattle fed a beta agonist in a commercial feedlot.

Science.gov (United States)

Hagenmaier, J A; Reinhardt, C D; Bartle, S J; Thomson, D U

2016-12-01

Feedlot cattle ( = 1,395; BW = 568 ± 43 kg) were used to evaluate the effects of shade on animal welfare, growth performance, and carcass quality during the summer of 2013 in a Kansas commercial feedlot. Seven lots of predominately black steers and heifers (4 and 3, respectively) visually determined to be approaching the final mo on feed were identified, randomly gate-sorted, and allocated to pens located across the feed alley from each other to receive 1 of 2 treatments: 1) Shade (mean shade area = 1.5 m/ animal) or 2) No shade. Shade was provided using a 13-ounce polyethylene fabric and pens were oriented northwest to southeast. The mean starting date was June 13 and the mean days on feed for lots while on the study was 38 d. Cattle were fed a 77.67% DM steam-flaked corn-based diet and had ad libitum access to water throughout the duration of the trial. Zilpaterol hydrochloride (ZIL) was included in the finishing ration at an inclusion rate of 8.3 mg/kg of DM for the last 20 d on feed with a 3 d withdrawal period. Pen floor temperatures (PFT) were measured using an infrared thermometer and prevalence of cattle open-mouth breathing (OMB) was recorded on a pen basis. In addition to shade treatment, the effect of temperature humidity index (THI) on PFT and OMB was analyzed by classifying days as either "Alert" (THI 79). On the day of slaughter, pens within a replicate were kept separate through all stages of the marketing channel from loading at the feedlot until stunning at the plant. Pen served as the experimental unit for all measurements. There was a THI × shade treatment interaction for PFT and OMB ( 0.05). Heat stress, a significant animal welfare concern and cause of reduced performance in feedlot cattle during the final phase of the feeding period, was alleviated in shaded cattle and illustrates the importance of shade provision as 1 tool to protect the welfare and increase feed consumption in large pens of feedlot cattle during hot summer months.

Study of the cathode region of mercury-free He-Xe low-pressure gas-discharge lamps with planar mesh electrode; Untersuchung der Kathodenregion von quecksilberfreien He-Xe Niederdruckgasentladungslampen mit planarer Geflechtelektrode

Energy Technology Data Exchange (ETDEWEB)

Winter, Joern

2009-12-04

In the present work the cathode region of a mercury-free helium-xenon low pressure discharge in spot mode was experimentally investigated. Due to the emission of electrons, the production of ions and metastable atoms as well as lifetime limiting processes the cathode region is of particular interest. To implement a discharge in spot mode a novel planar mesh electrode was developed and used as cathode. Applying the space resolved laser-atom-absorption-spectroscopy method (LAAS) the absolute particle densities of the two lowest excited xenon atoms and the gas temperature in the cathode region were determined, whereas the strong spot plasma inhomogeneity was considered. Both the excited xenon particle density and the gas temperature strongly decrease in radial and axial direction. Particularly the gas temperature has a value of about 650 K in a 1mm cathode distance and does clearly exceed room temperature. Furthermore the spectrum of the hot spot on the cathode surface was detected by means of optical emission spectroscopy. From this spectrum the temperature distribution of the cathode spot was obtained by fitting Planck's law. The temperature distribution shows a distinct maximum, which in dependence of the discharge current reaches values of 1414 K at 40 mA and 1524 K at 80 mA. From that maximum a steep direction-independent temperature decrease was obtained. A technological important aspect concerning the lifetime of a xenon based mercury-free discharge lamp is the problematic effect of the xenon gas consumption. In this work it is shown that in contrary to an industrial made standard cup electrode, which is broadly used in light advertising lamps, the gas consumption is negligible when applying the novel planar mesh electrode. This reduction of gas consumption is due to the generation of a hot spot along with high cathode temperature and low cathode fall voltage. (orig.)

Study of the cathode region of mercury-free He-Xe low-pressure gas-discharge lamps with planar mesh electrode; Untersuchung der Kathodenregion von quecksilberfreien He-Xe Niederdruckgasentladungslampen mit planarer Geflechtelektrode

Energy Technology Data Exchange (ETDEWEB)

Winter, Joern

2009-12-04

In the present work the cathode region of a mercury-free helium-xenon low pressure discharge in spot mode was experimentally investigated. Due to the emission of electrons, the production of ions and metastable atoms as well as lifetime limiting processes the cathode region is of particular interest. To implement a discharge in spot mode a novel planar mesh electrode was developed and used as cathode. Applying the space resolved laser-atom-absorption-spectroscopy method (LAAS) the absolute particle densities of the two lowest excited xenon atoms and the gas temperature in the cathode region were determined, whereas the strong spot plasma inhomogeneity was considered. Both the excited xenon particle density and the gas temperature strongly decrease in radial and axial direction. Particularly the gas temperature has a value of about 650 K in a 1mm cathode distance and does clearly exceed room temperature. Furthermore the spectrum of the hot spot on the cathode surface was detected by means of optical emission spectroscopy. From this spectrum the temperature distribution of the cathode spot was obtained by fitting Planck's law. The temperature distribution shows a distinct maximum, which in dependence of the discharge current reaches values of 1414 K at 40 mA and 1524 K at 80 mA. From that maximum a steep direction-independent temperature decrease was obtained. A technological important aspect concerning the lifetime of a xenon based mercury-free discharge lamp is the problematic effect of the xenon gas consumption. In this work it is shown that in contrary to an industrial made standard cup electrode, which is broadly used in light advertising lamps, the gas consumption is negligible when applying the novel planar mesh electrode. This reduction of gas consumption is due to the generation of a hot spot along with high cathode temperature and low cathode fall voltage. (orig.)

Influence of lucite phantoms on calibration of dosimetric pens

International Nuclear Information System (INIS)

Oliveira, E.C.; Xavier, M.; Caldas, L.E.V.

1992-01-01

Dosimetrical pens were studied for the answer repetition and were tested in gamma radiation fields ( 60 Co and 137 Cs) in air and in front of a lucite phantom, obtaining a backscattering contribution. The medium backscattering factors were 1,053 and 1,108 for respectively 60 Co and 137 Cs. The pens were placed behind the phantom for verifying the radiation attenuation. (C.G.C.)

Phase II Practice-based Evidence in Nutrition (PEN) evaluation: interviews with key informants.

Science.gov (United States)

Bowden, Fran Martin; Lordly, Daphne; Thirsk, Jayne; Corby, Lynda

2012-01-01

Dietitians of Canada has collaborated with experts in knowledge translation and transfer, technology, and dietetic practice to develop and implement an innovative online decision-support system called Practice-based Evidence in Nutrition (PEN). A study was conducted to evaluate the perceived facilitators and barriers that enable dietitians to use or prevent them from using PEN. As part of the overall evaluation framework of PEN, a qualitative descriptive research design was used to address the research purpose. Individual, semi-structured telephone interviews with 17 key informants were completed, and the interview transcripts underwent qualitative content analysis. Respondents identified several facilitators of and barriers to PEN use. Facilitators included specificity to dietetics, rigorous/expert review, easy accessibility, current content, credible/secure material, well-organized/easy-to-use material, material that is valuable to practice, and good value for money. Barriers included perceived high cost, fee structuring/cost to students, certain organizational aspects, and a perceived lack of training for pathway contributors. This formative evaluation has indicated areas in which PEN could be improved and strategies to make PEN the standard for dietetic education and practice. Ensuring that PEN is meeting users' knowledge needs is of the utmost importance if dietitians are to remain on the cutting edge of scientific inquiry.

Initial operation of the CW 8X H- ion source discharge

International Nuclear Information System (INIS)

Smith, H.V. Jr.; Allison, P.; Geisik, C.; Schmitt, D.R.; Schneider, J.D.; Stelzer, J.E.

1993-01-01

A pulsed 8Χ source was built and the H - beam current, emittance, and power efficiency were measured. These results were promising, so a cooled, dc version designed for operation at arc power levels up to 30 kW was built. Testing of the CW 8Χ source discharge is underway. The design dc power loading on the cathode surface is 900 W/cm 2 , considerably higher than achieved in any pervious Penning surface-plasma source (SPS). Thus, the electrode surfaces are cooled with pressurized, hot water. We describe the source and present the initial operating experience and arc test results

Initial operation of the CW 8X H- ion source discharge

International Nuclear Information System (INIS)

Smith, H.V. Jr.; Allison, P.; Geisik, C.; Schmitt, D.R.; Schneider, J.D.; Stelzer, J.E.

1993-01-01

A pulsed 8X source was built and the H - beam current, emittance, and power efficiency were measured. These results were promising, so a cooled, dc version designed for operation at arc power levels up to 30 kW was built. Testing of the CW 8X source discharge is underway. The design dc power loading on the cathode surface is 900 W/cm 2 , considerably higher than achieved in any previous Penning surface-plasma source (SPS). Thus, the electrode surfaces are cooled with pressurized, hot water. The authors describe the source and present the initial operating experience and arc test results

Fast and Simple Forensic Red Pen Ink Analysis Using Ultra-Performance Liquid Chromatography (UPLC)

International Nuclear Information System (INIS)

Lee, L.C.; Ying, S.L.; Wan Nur Syazwani Wan Mohamad Fuad; Ab Aziz Ishak; Khairul Osman

2016-01-01

Ultra-performance liquid chromatography (UPLC) is more effective than high performance liquid chromatography in terms of analysis speed and sensitivity. This paper presents a feasibility study on forensic red pen inks analysis using UPLC. A total of 12 varieties of red ball point pen inks were purchased from selected stationary shop. For each variety, four different individual pens were sampled to provide intra-variability within a particular variety of pen. The proposed approach is very simple that it only involved limited analysis step and chemicals. A total of 144 chromatograms were obtained from red ink entries extracted with 1.5 mL 80 % (v/v) acetonitrile. Peaks originated from pen inks were determined by comparing the chromatograms of both blank paper and blank solvent against that of ink samples. Subsequently, one-way ANOVA was conducted to discriminate all 66 possible pairs for red pen inks. Results showed that the proposed approach giving discriminating power of 95.45 %. The outcome of the study indicates that UPLC could be a fast and simple approach to red ball point pen inks analysis. (author)

Innovation & evaluation of tangible direct manipulation digital drawing pens for children.

Science.gov (United States)

Lee, Tai-Hua; Wu, Fong-Gong; Chen, Huei-Tsz

2017-04-01

Focusing on the theme of direct manipulation, in this study, we proposed a new and innovative tangible user interface (TUI) design concept for a manipulative digital drawing pen. Based on interviews with focus groups brainstorming and experts and the results of a field survey, we selected the most suitable tangible user interface for children between 4 and 7 years of age. Using the new tangible user interface, children could choose between the brush tools after touching and feeling the various patterns. The thickness of the brush could be adjusted by changing the tilt angle. In a subsequent experimental process we compared the differences in performance and subjective user satisfaction. A total of sixteen children, aged 4-7 years participated in the experiment. Two operating system experiments (the new designed tangible digital drawing pen and traditional visual interface-icon-clicking digital drawing pens) were performed at random and in turns. We assessed their manipulation performance, accuracy, brush stroke richness and subjective evaluations. During the experimental process we found that operating functions using the direct manipulation method, and adding shapes and semantic models to explain the purpose of each function, enabled the children to perform stroke switches relatively smoothly. By using direct manipulation digital pens, the children could improve their stroke-switching performance for digital drawing. Additionally, by using various patterns to represent different brushes or tools, the children were able to make selections using their sense of touch, thereby reducing the time required to move along the drawing pens and select icons (The significant differences (p = 0.000, p drawing thick lines using the crayon function of the two (new and old) drawing pens (new 5.8750 drawing operations enhanced the drawing results, thereby increasing the children's enjoyment of drawing with tangible digital drawing pens. Copyright © 2016 Elsevier Ltd. All

Evaluation of Cathode Air Flow Transients in a SOFC/GT Hybrid System Using Hardware in the Loop Simulation.

Science.gov (United States)

Zhou, Nana; Yang, Chen; Tucker, David

2015-02-01

Thermal management in the fuel cell component of a direct fired solid oxide fuel cell gas turbine (SOFC/GT) hybrid power system can be improved by effective management and control of the cathode airflow. The disturbances of the cathode airflow were accomplished by diverting air around the fuel cell system through the manipulation of a hot-air bypass valve in open loop experiments, using a hardware-based simulation facility designed and built by the U.S. Department of Energy, National Energy Technology Laboratory (NETL). The dynamic responses of the fuel cell component and hardware component of the hybrid system were studied in this paper.

Chemical composition of felt-tip pen inks.

Science.gov (United States)

Germinario, Giulia; Garrappa, Silvia; D'Ambrosio, Valeria; van der Werf, Inez Dorothé; Sabbatini, Luigia

2018-01-01

Felt-tip pens are frequently used for the realization of sketches, drawings, architectural projects, and other technical designs. The formulations of these inks are usually rather complex and may be associated to those of modern paint materials where, next to the binding medium and pigments/dyes, solvents, fillers, emulsifiers, antioxidants, plasticizers, light stabilizers, biocides, and so on are commonly added. Felt-tip pen inks are extremely sensitive to degradation and especially exposure to light may cause chromatic changes and fading. In this study, we report on the complete chemical characterization of modern felt-tip pen inks that are commercially available and commonly used for the realization of artworks. Three brands of felt-tip pens (Faber-Castell, Edding, and Stabilo) were investigated with complementary analytical techniques such as thin-layer chromatography (TLC), VIS-reflectance spectroscopy, μ-Raman spectroscopy, surface-enhanced Raman spectroscopy (SERS), pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS), GC-MS, and Fourier transform infrared (FTIR) spectroscopy. The use of TLC proved to be very powerful in the study of complex mixtures of synthetic dyes. First derivatives of the reflectance spectra acquired on the TLC spots were useful in the preliminary identification of the dye, followed by Raman spectroscopy and SERS, which allowed for the unambiguous determination of the chemical composition of the pigments (phthalocyanines, dioxazines, and azo pigments) and dyes (azo dyes, triarylmethanes, xanthenes). FTIR spectroscopy was used especially for the detection of additives, as well as for confirming the nature of solvents and dyes/pigments. Finally, (Py-)GC-MS data provided information on the binders (styrene-acrylic resins, plant gums), solvents, and additives, as well as on pigments and dyes.

A redesigned follitropin alfa pen injector for infertility: results of a market research study

Directory of Open Access Journals (Sweden)

Abbotts C

2011-06-01

Full Text Available Carole Abbotts1, Cristiana Salgado-Braga2, Céline Audibert-Gros31Pharmaceutical Marketing Research Consultancy, London, UK; 2Fertility and Endocrinology Global Business Unit, 3Business Intelligence, Merck Serono SA, Geneva, SwitzerlandBackground: The purpose of this study was to evaluate patient-learning and nurse-teaching experiences when using a redesigned prefilled, ready-to-use follitropin alfa pen injector.Methods: Seventy-three UK women of reproductive age either administering daily treatment with self-injectable gonadotropins or about to start gonadotropin treatment for infertility (aged 24–47 years; 53 self-injection-experienced and 20 self-injection-naïve and 28 nurses from UK infertility clinics were recruited for the study. Following instruction, patients and nurses used the redesigned follitropin alfa pen to inject water into an orange and completed questionnaires to evaluate their experiences with the pen immediately after the simulated injections.Results: Most (88%, n = 64 patients found it easy to learn how to use the pen. Among injection-experienced patients, 66% (n = 35 agreed that the redesigned pen was easier to learn to use compared with their current method and 70% (n = 37 also said they would prefer its use over current devices for all injectable fertility medications. All nurses considered the redesigned pen easy to learn and believed it would be easy to teach patients how to use. Eighty-six percent (n = 24 of the nurses thought it was easy to teach patients to determine the remaining dose to be dialed and injected in a second pen if the initial dose was incomplete. Compared with other injection devices, 96% (n = 27 thought it was "much easier" to "as easy" to teach patients to use the redesigned pen. Based on ease of teaching, 68% (n = 19 of nurses would choose to teach the pen in preference to any other injection method. Almost all (93%, n = 26 nurses considered that having the same pen format for a range of

Update on insulin treatment for dogs and cats: insulin dosing pens and more

Directory of Open Access Journals (Sweden)

Thompson A

2015-04-01

Full Text Available Ann Thompson,1 Patty Lathan,2 Linda Fleeman3 1School of Veterinary Science, The University of Queensland, Gatton, QLD, Australia; 2College of Veterinary Medicine Mississippi State University, Starkville, MS, USA; 3Animal Diabetes Australia, Melbourne, VIC, Australia Abstract: Insulin therapy is still the primary therapy for all diabetic dogs and cats. Several insulin options are available for each species, including veterinary registered products and human insulin preparations. The insulin chosen depends on the individual patient's requirements. Intermediate-acting insulin is usually the first choice for dogs, and longer-acting insulin is the first choice for cats. Once the insulin type is chosen, the best method of insulin administration should be considered. Traditionally, insulin vials and syringes have been used, but insulin pen devices have recently entered the veterinary market. Pens have different handling requirements when compared with standard insulin vials including: storage out of the refrigerator for some insulin preparations once pen cartridges are in use; priming of the pen to ensure a full dose of insulin is administered; and holding the pen device in place for several seconds during the injection. Many different types of pen devices are available, with features such as half-unit dosing, large dials for visually impaired people, and memory that can display the last time and dose of insulin administered. Insulin pens come in both reusable and disposable options. Pens have several benefits over syringes, including improved dose accuracy, especially for low insulin doses. Keywords: diabetes, mellitus, canine, feline, NPH, glargine, porcine lente

Nanocrystalline electrodeposited Ni-Mo-C cathodes for hydrogen production

International Nuclear Information System (INIS)

Hashimoto, K.; Sasaki, T.; Meguro, S.; Asami, K.

2004-01-01

Tailoring active nickel alloy cathodes for hydrogen evolution in a hot concentrated hydroxide solution was attempted by electrodeposition. The carbon addition to Ni-Mo alloys decreased the nanocrystalline grain size and remarkably enhanced the activity for hydrogen evolution, changing the mechanism of hydrogen evolution. The Tafel slope of hydrogen evolution was about 35 mV per decade. This suggested that the rate-determining step is desorption of adsorbed hydrogen atoms by recombination. As was distinct from the binary Ni-Mo alloys, after open circuit immersion, the overpotential, that is, the activity of nanocrystalline Ni-Mo-C alloys for hydrogen evolution was not changed, indicating the sufficient durability in the practical electrolysis

Dynamic monitoring of weight data at the pen vs at the individual level

DEFF Research Database (Denmark)

Jensen, Dan; Toft, Nils; Kristensen, A. R. K.

recorded weight data from finisher pigs. Data are collected at insertion and at the exit of the first pigs in the pen, and in few pens, the weight is recorded weekly. Dynamic linear models are fitted on the weight data, at the pig level (univariate), at the double pen level using averaged weight...... (univariate) and using individual pig values as parameters in a hierarchical (multivariate) model including section, double pen, and individual level. Variance components of the different models are estimated using the Expectation Maximization algorithm. The difference of information obtained...... at the individual vs pen level is thereafter assessed. Whereas weight data is usually monitored after a batch is being sent to the slaughter house, this method provides weekly updating of the data. Perspectives of application include dynamic monitoring of weight data in relation to events such as diarrhoea, tail...

Dynamic monitoring of weight data at the pen vs at the individual level

DEFF Research Database (Denmark)

Jensen, Dan Børge; Toft, Nils; Kristensen, Anders Ringgaard

recorded weight data from finisher pigs. Data are collected at insertion and at the exit of the first pigs in the pen, and in few pens, the weight is recorded weekly. Dynamic linear models are fitted on the weight data, at the pig level (univariate), at the double pen level using averaged weight...... (univariate) and using individual pig values as parameters in a hierarchical (multivariate) model including section, double pen, and individual level. Variance components of the different models are estimated using the Expectation Maximization algorithm. The difference of information obtained...... at the individual vs. pen level is thereafter assessed. Whereas weight data is usually monitored after a batch is being sent to the slaughter house, this method provides with weekly updating of the data. Perspectives of application include dynamic monitoring of weight data in relation to events such as diarrhoea...

Cathode materials review

Science.gov (United States)

Daniel, Claus; Mohanty, Debasish; Li, Jianlin; Wood, David L.

2014-06-01

The electrochemical potential of cathode materials defines the positive side of the terminal voltage of a battery. Traditionally, cathode materials are the energy-limiting or voltage-limiting electrode. One of the first electrochemical batteries, the voltaic pile invented by Alessandro Volta in 1800 (Phil. Trans. Roy. Soc. 90, 403-431) had a copper-zinc galvanic element with a terminal voltage of 0.76 V. Since then, the research community has increased capacity and voltage for primary (nonrechargeable) batteries and round-trip efficiency for secondary (rechargeable) batteries. Successful secondary batteries have been the lead-acid with a lead oxide cathode and a terminal voltage of 2.1 V and later the NiCd with a nickel(III) oxide-hydroxide cathode and a 1.2 V terminal voltage. The relatively low voltage of those aqueous systems and the low round-trip efficiency due to activation energies in the conversion reactions limited their use. In 1976, Wittingham (J. Electrochem. Soc., 123, 315) and Besenhard (J. Power Sources 1(3), 267) finally enabled highly reversible redox reactions by intercalation of lithium ions instead of by chemical conversion. In 1980, Goodenough and Mizushima (Mater. Res. Bull. 15, 783-789) demonstrated a high-energy and high-power LiCoO2 cathode, allowing for an increase of terminal voltage far beyond 3 V. Over the past four decades, the international research community has further developed cathode materials of many varieties. Current state-of-the-art cathodes demonstrate voltages beyond any known electrolyte stability window, bringing electrolyte research once again to the forefront of battery research.

Cathode materials review

International Nuclear Information System (INIS)

Daniel, Claus; Mohanty, Debasish; Li, Jianlin; Wood, David L.

2014-01-01

The electrochemical potential of cathode materials defines the positive side of the terminal voltage of a battery. Traditionally, cathode materials are the energy-limiting or voltage-limiting electrode. One of the first electrochemical batteries, the voltaic pile invented by Alessandro Volta in 1800 (Phil. Trans. Roy. Soc. 90, 403-431) had a copper-zinc galvanic element with a terminal voltage of 0.76 V. Since then, the research community has increased capacity and voltage for primary (nonrechargeable) batteries and round-trip efficiency for secondary (rechargeable) batteries. Successful secondary batteries have been the lead-acid with a lead oxide cathode and a terminal voltage of 2.1 V and later the NiCd with a nickel(III) oxide-hydroxide cathode and a 1.2 V terminal voltage. The relatively low voltage of those aqueous systems and the low round-trip efficiency due to activation energies in the conversion reactions limited their use. In 1976, Wittingham (J. Electrochem. Soc., 123, 315) and Besenhard (J. Power Sources 1(3), 267) finally enabled highly reversible redox reactions by intercalation of lithium ions instead of by chemical conversion. In 1980, Goodenough and Mizushima (Mater. Res. Bull. 15, 783-789) demonstrated a high-energy and high-power LiCoO 2 cathode, allowing for an increase of terminal voltage far beyond 3 V. Over the past four decades, the international research community has further developed cathode materials of many varieties. Current state-of-the-art cathodes demonstrate voltages beyond any known electrolyte stability window, bringing electrolyte research once again to the forefront of battery research

Cathode materials review

Energy Technology Data Exchange (ETDEWEB)

Daniel, Claus, E-mail: danielc@ornl.gov; Mohanty, Debasish, E-mail: danielc@ornl.gov; Li, Jianlin, E-mail: danielc@ornl.gov; Wood, David L., E-mail: danielc@ornl.gov [Oak Ridge National Laboratory, 1 Bethel Valley Road, MS6472 Oak Ridge, TN 37831-6472 (United States)

2014-06-16

The electrochemical potential of cathode materials defines the positive side of the terminal voltage of a battery. Traditionally, cathode materials are the energy-limiting or voltage-limiting electrode. One of the first electrochemical batteries, the voltaic pile invented by Alessandro Volta in 1800 (Phil. Trans. Roy. Soc. 90, 403-431) had a copper-zinc galvanic element with a terminal voltage of 0.76 V. Since then, the research community has increased capacity and voltage for primary (nonrechargeable) batteries and round-trip efficiency for secondary (rechargeable) batteries. Successful secondary batteries have been the lead-acid with a lead oxide cathode and a terminal voltage of 2.1 V and later the NiCd with a nickel(III) oxide-hydroxide cathode and a 1.2 V terminal voltage. The relatively low voltage of those aqueous systems and the low round-trip efficiency due to activation energies in the conversion reactions limited their use. In 1976, Wittingham (J. Electrochem. Soc., 123, 315) and Besenhard (J. Power Sources 1(3), 267) finally enabled highly reversible redox reactions by intercalation of lithium ions instead of by chemical conversion. In 1980, Goodenough and Mizushima (Mater. Res. Bull. 15, 783-789) demonstrated a high-energy and high-power LiCoO{sub 2} cathode, allowing for an increase of terminal voltage far beyond 3 V. Over the past four decades, the international research community has further developed cathode materials of many varieties. Current state-of-the-art cathodes demonstrate voltages beyond any known electrolyte stability window, bringing electrolyte research once again to the forefront of battery research.

A Survey of Pen name semantic Applications in Rumis Sonnets (Ghazals

Directory of Open Access Journals (Sweden)

Zohre AhmadiPoor anari

2015-04-01

Full Text Available Abstract The pen name in sonnet is the poet’s poetic name which most of the poets mention it in their verses. Jalāl ad-Dīn Muhammad Balkhī also known as Jalāl ad-Dīn Rumi lived in 13th-century was a Persian Moslem poet, theologian, and Sufi mystic. He has written more than 3229 sonnets and dedicated to Shams Tabrizi. Thus mentioned, names such “Shams”, “Shams od-Din” and “Shams al-Haq” in the ending lines of his sonnets.    One of the points which could be studied about pen name is study of theme or concepts which are mentioned alongside that. Entirely it has been said that the same theme which comes with the pen name “Shams” in 992 sonnets. In this study, we pay attention to mentioning the poets desired name which is not necessarily the pen name in Rumis’ sonnets, what theme does it carry and what is relationship of it with the previous lines?    Themes which the poets apply in their sonnets beside pen name is mostly what that has been mentioned in the previous lines. However, in times the concept mentioned along side with the pen name is independent from the sonnet concepts, mostly eulogy. Studying Hafiz and Saadi sonnets shows that the most important themes existing are: love declaration, advice, eulogizing and sometimes a mischievous concept.    Rumis’ sonnets are lover-based. Therefore, there is much talk of the lover in the whole sonnet. But in other poet’s sonnets, the lover (the poet is the main theme is the sonnet. The poet may find a way to praise his own poem or stays in his dreamy world and focuses on the romantic feelings. Considering the fact that unlike other poets Rumi has not mentioned his own pen name but his lover “Shams”, the study focuses on the themes which are mentioned by the pen name “Shams” as the following: 1-Eulogy: One third of the Shams pen names are eulogies. The sufist approach has given the lines a special color. The similes and metaphors used for him are heavenly and

The influence of cathode excavation of cathodic arc evaporator on thickness uniformity and erosion products angle distribution

Directory of Open Access Journals (Sweden)

D. V. Duhopel'nikov

2014-01-01

Full Text Available Cathodic arc evaporators are used for coating with functional films. Prolonged or buttend evaporators may be used for this purposes. In butt-end evaporator the cathode spots move continuously on the cathode work surface and evaporate cathode material. High depth excavation profile forms on the cathode work surface while the thick coating precipitation (tens or hundreds of microns. The cathode excavation profile is shaped like a “cup” with high walls for electrostatic discharge stabilization systems with axial magnetic fields. Cathode spots move on the bottom of the “cup”. It is very likely that high “cup” walls are formed as a result of lasting work time influence on the uniformity of precipitated films.In the present work the influence of excavation profile walls height on the uniformity of precipitated coating was carried out. The high profile walls are formed due to lasting work of DC vacuum arc evaporator. The cathode material used for tests was 3003 aluminum alloy. The extended substrate was placed parallel to the cathode work surface. Thickness distribution along the substrate length with the new cathode was obtained after 6 hours and after 12 hours of continuous operation.The thickness distribution of precipitated coating showed that the cathode excavation has an influence on the angular distribution of the matter escaping the cathode. It can be clearly seen from the normalized dependence coating thickness vs the distance from the substrate center. Also the angular distribution of the matter flow from the cathode depending on the cathode working time was obtained. It was shown that matter flow from the cathode differs from the LambertKnudsen law. The more the cathode excavation the more this difference.So, cathode excavation profile has an influence on the uniformity of precipitated coating and it is necessary to take in account the cathode excavation profile while coating the thick films.

Nanostructured sulfur cathodes

KAUST Repository

Yang, Yuan

2013-01-01

Rechargeable Li/S batteries have attracted significant attention lately due to their high specific energy and low cost. They are promising candidates for applications, including portable electronics, electric vehicles and grid-level energy storage. However, poor cycle life and low power capability are major technical obstacles. Various nanostructured sulfur cathodes have been developed to address these issues, as they provide greater resistance to pulverization, faster reaction kinetics and better trapping of soluble polysulfides. In this review, recent developments on nanostructured sulfur cathodes and mechanisms behind their operation are presented and discussed. Moreover, progress on novel characterization of sulfur cathodes is also summarized, as it has deepened the understanding of sulfur cathodes and will guide further rational design of sulfur electrodes. © 2013 The Royal Society of Chemistry.

The Possible Role of Penning Ionization Processes in Planetary Atmospheres

Directory of Open Access Journals (Sweden)

Stefano Falcinelli

2015-03-01

Full Text Available In this paper we suggest Penning ionization as an important route of formation for ionic species in upper planetary atmospheres. Our goal is to provide relevant tools to researchers working on kinetic models of atmospheric interest, in order to include Penning ionizations in their calculations as fast processes promoting reactions that cannot be neglected. Ions are extremely important for the transmission of radio and satellite signals, and they govern the chemistry of planetary ionospheres. Molecular ions have also been detected in comet tails. In this paper recent experimental results concerning production of simple ionic species of atmospheric interest are presented and discussed. Such results concern the formation of free ions in collisional ionization of H2O, H2S, and NH3 induced by highly excited species (Penning ionization as metastable noble gas atoms. The effect of Penning ionization still has not been considered in the modeling of terrestrial and extraterrestrial objects so far, even, though metastable helium is formed by radiative recombination of He+ ions with electrons. Because helium is the second most abundant element of the universe, Penning ionization of atomic or molecular species by He*(23S1 is plausibly an active route of ionization in relatively dense environments exposed to cosmic rays.

Arcjet cathode phenomena

Science.gov (United States)

Curran, Francis M.; Haag, Thomas W.; Raquet, John F.

1989-01-01

Cathode tips made from a number of different materials were tested in a modular arcjet thruster in order to examine cathode phenomena. Periodic disassembly and examination, along with the data collected during testing, indicated that all of the tungsten-based materials behaved similarly despite the fact that in one of these samples the percentage of thorium oxide was doubled and another was 25 percent rhenium. The mass loss rate from a 2 percent thoriated rhenium cathode was found to be an order of magnitude greater than that observed using 2 percent thoriated tungsten. Detailed analysis of one of these cathode tips showed that the molten crater contained pure tungsten to a depth of about 150 microns. Problems with thermal stress cracking were encountered in the testing of a hafnium carbide tip. Post test analysis showed that the active area of the tip had chemically reacted with the propellant. A 100 hour continuous test was run at about 1 kW. Post test analysis revealed no dendrite formation, such as observed in a 30 kW arcjet lifetest, near the cathode crater. The cathodes from both this test and a previously run 1000 hour cycled test displayed nearly identical arc craters. Data and calculations indicate that the mass losses observed in testing can be explained by evaporation.

Analysis of the NovoTwist pen needle in comparison with conventional screw-thread needles.

Science.gov (United States)

Aye, Tandy

2011-11-01

Administration of insulin via a pen device may be advantageous over a vial and syringe system. Hofman and colleagues introduce a new insulin pen needle, the NovoTwist, to simplify injections to a small group of children and adolescents. Their overall preferences and evaluation of the handling of the needle are reported in the study. This new needle has the potential to ease administration of insulin via a pen device that may increase both the use of a pen device and adherence to insulin therapy. © 2011 Diabetes Technology Society.

Recent H- diagnostics, plasma simulations, and 2X scaled Penning ion source developments at the Rutherford Appleton Laboratory

Science.gov (United States)

Lawrie, S. R.; Faircloth, D. C.; Smith, J. D.; Sarmento, T. M.; Whitehead, M. O.; Wood, T.; Perkins, M.; Macgregor, J.; Abel, R.

2018-05-01

A vessel for extraction and source plasma analyses is being used for Penning H- ion source development at the Rutherford Appleton Laboratory. A new set of optical elements including an einzel lens has been installed, which transports over 80 mA of H- beam successfully. Simultaneously, a 2X scaled Penning source has been developed to reduce cathode power density. The 2X source is now delivering a 65 mA H- ion beam at 10% duty factor, meeting its design criteria. The long-term viability of the einzel lens and 2X source is now being evaluated, so new diagnostic devices have been installed. A pair of electrostatic deflector plates is used to correct beam misalignment and perform fast chopping, with a voltage rise time of 24 ns. A suite of four quartz crystal microbalances has shown that the cesium flux in the vacuum vessel is only increased by a factor of two, despite the absence of a dedicated cold trap. Finally, an infrared camera has demonstrated good agreement with thermal simulations but has indicated unexpected heating due to beam loss on the downstream electrode. These types of diagnostics are suitable for monitoring all operational ion sources. In addition to experimental campaigns and new diagnostic tools, the high-performance VSim and COMSOL software packages are being used for plasma simulations of two novel ion thrusters for space propulsion applications. In parallel, a VSim framework has been established to include arbitrary temperature and cesium fields to allow the modeling of surface physics in H- ion sources.

Increasing viscosity and inertia using a robotically-controlled pen improves handwriting in children

Science.gov (United States)

Ben-Pazi, Hilla; Ishihara, Abraham; Kukke, Sahana; Sanger, Terence D

2010-01-01

The aim of this study was to determine the effect of mechanical properties of the pen on the quality of handwriting in children. Twenty two school aged children, ages 8–14 years wrote in cursive using a pen attached to a robot. The robot was programmed to increase the effective weight (inertia) and stiffness (viscosity) of the pen. Speed, frequency, variability, and quality of the two handwriting samples were compared. Increased inertia and viscosity improved handwriting quality in 85% of children (pHandwriting quality did not correlate with changes in speed, suggesting that improvement was not due to reduced speed. Measures of movement variability remained unchanged, suggesting that improvement was not due to mechanical smoothing of pen movement by the robot. Since improvement was not explained by reduced speed or mechanical smoothing, we conclude that children alter handwriting movements in response to pen mechanics. Altered movement could be caused by changes in proprioceptive sensory feedback. PMID:19794098

Penning ionization cross sections of excited rare gas atoms

International Nuclear Information System (INIS)

Ukai, Masatoshi; Hatano, Yoshihiko.

1988-01-01

Electronic energy transfer processes involving excited rare gas atoms play one of the most important roles in ionized gas phenomena. Penning ionization is one of the well known electronic energy transfer processes and has been studied extensively both experimentally and theoretically. The present paper reports the deexcitation (Penning ionization) cross sections of metastable state helium He(2 3 S) and radiative He(2 1 P) atoms in collision with atoms and molecules, which have recently been obtained by the authors' group by using a pulse radiolysis method. Investigation is made of the selected deexcitation cross sections of He(2 3 S) by atoms and molecules in the thermal collisional energy region. Results indicate that the cross sections are strongly dependent on the target molecule. The deexcitation probability of He(2 3 S) per collision increases with the excess electronic energy of He(2 3 S) above the ionization potential of the target atom or molecule. Another investigation, made on the deexcitation of He(2 1 P), suggests that the deexcitation cross section for He(2 1 P) by Ar is determined mainly by the Penning ionization cross section due to a dipole-dipole interaction. Penning ionization due to the dipole-dipole interaction is also important for deexcitation of He(2 1 P) by the target molecules examined. (N.K.)

( sup 3 H)(D-PEN sup 2 , D-PEN sup 5 ) enkephalin binding to delta opioid receptors on intact neuroblastoma-glioma (NG 108-15) hybrid cells

Energy Technology Data Exchange (ETDEWEB)

Knapp, R.J.; Yamamura, H.I. (Univ. of Arizona College of Medicine, Tucson (USA))

1990-01-01

({sup 3}H)(D-Pen{sup 2}, D-Pen{sup 5})enkephalin binding to intact NG 108-15 cells has been measured under physiological conditions of temperature and medium. The dissociation constant, receptor density, and Hill slope values measured under these conditions are consistent with values obtained by others using membranes prepared from these cells. Kinetic analysis of the radioligand binding to these cells show biphasic association and monophasic dissociation processes suggesting the presence of different receptor affinity states for the agonist. The data show that the binding affinity of ({sup 3}H)(D-Pen{sup 2}, D-Pen{sup 5})enkephalin under physiological conditions is not substantially different to that measured in 50 mM Tris buffer using cell membrane fractions. Unlike DPDPE, the {mu} opioid agonists morphine, normorphine, PL-17, and DAMGO, have much lower affinity for the {delta} receptor measured under these conditions than is observed by studies using 50 mM Tris buffer. The results described here suggest that this assay may serve as a useful model of {delta} opioid receptor binding in vivo.

Barium transport in the hot spot region of fluorescent lamps

International Nuclear Information System (INIS)

Sigeneger, F; Rackow, K; Uhrlandt, D; Ehlbeck, J; Lieder, G

2010-01-01

The transport of barium atoms and ions in the vicinity of the hot spot in fluorescent lamps operating at 25 kHz is investigated by a combined experimental and theoretical approach. By laser-induced fluorescence, the particle densities of barium atoms and ions were measured time-resolved at different distances from the spot centre. In addition, the time-dependent cathode fall voltage was measured using an improved band method. The model combines a kinetic part for the electrons with a fluid part for the barium atoms and ions. Both parts are spatially resolved in spherically symmetric geometry. The space-dependent electron Boltzmann equation yields the electron density and the ionization rate coefficient of barium as functions of the cathode fall voltage. These results are used to solve the time-dependent particle balance equations of barium atoms and ions which include the ionization of barium as gain and loss terms, respectively. Good agreement between the measured and calculated particle densities of barium atoms is obtained. A sensitive dependence of the ionization frequency and of the barium particle densities on the cathode fall voltage was found.

Pen-Enabled, Real-Time Student Engagement for Teaching in STEM Subjects

Science.gov (United States)

Urban, Sylvia

2017-01-01

The introduction of pen-enabling devices has been demonstrated to increase a student's ability to solve problems, communicate, and learn during note taking. For the science, technology, engineering, and mathematics subjects that are considered to be symbolic in nature, pen interfaces are better suited for visual-spatial content and also provide a…

Public debate on the Penly 3 project. Construction of an electronuclear production unit of the Penly site (Seine-Maritime)

International Nuclear Information System (INIS)

2010-01-01

After a presentation of the objectives of the Penly 3 project, this report gives an overview of the context of electricity production (increasing world demand, geographically unbalanced energy reserves with fluctuating prices and a tendency to increase, French energy assessment, electricity peculiarities, electricity production and consumption in France in 2009, climate change issue). It presents the Penly 3 project and its alternatives within the frame of the French environment and energy policy. The project is then presented in terms of safety objectives, of design choices, of environmental improvements (water sampling, thermal, chemical and radioactive releases, wastes, sound and visual impact, foreseen cost and financing), and then in terms of socio-economical impact. The main steps of the project are briefly indicated

Product Plan of New Generation System Camera "OLYMPUS PEN E-P1"

Science.gov (United States)

Ogawa, Haruo

"OLYMPUS PEN E-P1", which is new generation system camera, is the first product of Olympus which is new standard "Micro Four-thirds System" for high-resolution mirror-less cameras. It continues good sales by the concept of "small and stylish design, easy operation and SLR image quality" since release on July 3, 2009. On the other hand, the half-size film camera "OLYMPUS PEN" was popular by the concept "small and stylish design and original mechanism" since the first product in 1959 and recorded sale number more than 17 million with 17 models. By the 50th anniversary topic and emotional value of the Olympus pen, Olympus pen E-P1 became big sales. I would like to explain the way of thinking of the product plan that included not only the simple functional value but also emotional value on planning the first product of "Micro Four-thirds System".

Pen harvester for powering a pulse rate sensor

International Nuclear Information System (INIS)

Bedekar, Vishwas; Oliver, Josiah; Priya, Shashank

2009-01-01

Rapid developments in the area of micro-sensors for various applications such as structural health monitoring, bio-chemical sensors and pressure sensors have increased the demand for portable, low cost, high efficiency energy harvesting devices. In this paper, we describe the scheme for powering a pulse rate sensor with a vibration energy harvester integrated inside a pen commonly carried by humans in the pocket close to the heart. Electromagnetic energy harvesting was selected in order to achieve high power at lower frequencies. The prototype pen harvester was found to generate 3 mW at 5 Hz and 1 mW at 3.5 Hz operating under displacement amplitude of 16 mm (corresponding to an acceleration of approximately 1.14 g rms at 5 Hz and 0.56 g rms at 3.5 Hz, respectively). A comprehensive mathematical modelling and simulations were performed in order to optimize the performance of the vibration energy harvester. The integrated pen harvester prototype was found to generate continuous power of 0.46-0.66 mW under normal human actions such as jogging and jumping which is enough for a small scale pulse rate sensor.

Beam-plasma interaction with an electron beam injecting into a symmetrically open plasma system; Electron beam relaxation. Puchkovo-plazmennoe vzaimodejstvie pri inzhektsii ehlektronnogo puchka v simmetrichno otkrytuyu plazmennuyu sistemu; Relaksatsiya ehlektronnogo puchka

Energy Technology Data Exchange (ETDEWEB)

Opanasenko, A V; Romanyuk, L I [AN Ukrainskoj SSR, Kiev (Ukrainian SSR). Inst. Yadernykh Issledovanij

1989-10-01

The relaxation of the electron beam with the electron density of 1-2 keV injected through the symmetrically open plasma system with the independent hot cathode Penning discharge is experimentally investigated. It is shown that the velocity distribution function of the electron beam changes after passing each wave generation zone induced by the beam. The contribution of different wave zones to the beam relaxation depends on the prehistory of the beam-plasma interaction and may be regulated by the selection of the plasma system parameters. By this way the complete relaxation of the electron beam can be achieved after the beam crossing the whole system.

9 CFR 89.5 - Feeding pens.

Science.gov (United States)

2010-01-01

... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Feeding pens. 89.5 Section 89.5 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE INTERSTATE TRANSPORTATION OF ANIMALS (INCLUDING POULTRY) AND ANIMAL PRODUCTS STATEMENT OF POLICY UNDER THE...

Ballpoint pen ingestion in a 2-year-old child.

Science.gov (United States)

Rameau, Anaïs; Anand, Sumeet M; Nguyen, Lily H

2011-07-01

A 2-year-old girl ingested a ballpoint pen, which was found on chest x-ray to have lodged in the lower esophagus and stomach. The pen, which measured nearly 15 cm in length, was removed via rigid esophagoscopy without complication. To the best of our knowledge, this is the longest nonflexible foreign body ingested by a young child ever reported in the English-language literature. We describe the presentation of this case and the current guidelines for safety as enumerated in the Small Parts Regulations established by the U.S. Consumer Product Safety Commission.

Nonlinear PIC simulation in a Penning trap

International Nuclear Information System (INIS)

Lapenta, G.; Delzanno, G.L.; Finn, J. M.

2002-01-01

We study the nonlinear dynamics of a Penning trap plasma, including the effect of the finite length and end curvature of the plasma column. A new cylindrical PIC code, called KANDINSKY, has been implemented by using a new interpolation scheme. The principal idea is to calculate the volume of each cell from a particle volume, in the same manner as it is done for the cell charge. With this new method, the density is conserved along streamlines and artificial sources of compressibility are avoided. The code has been validated with a reference Eulerian fluid code. We compare the dynamics of three different models: a model with compression effects, the standard Euler model and a geophysical fluid dynamics model. The results of our investigation prove that Penning traps can really be used to simulate geophysical fluids

Erosion behavior of composite Al-Cr cathodes in cathodic arc plasmas in inert and reactive atmospheres

Energy Technology Data Exchange (ETDEWEB)

Franz, Robert, E-mail: robert.franz@unileoben.ac.at; Mendez Martin, Francisca; Hawranek, Gerhard [Montanuniversität Leoben, Franz-Josef-Strasse 18, 8700 Leoben (Austria); Polcik, Peter [Plansee Composite Materials GmbH, Siebenbürgerstrasse 23, 86983 Lechbruck am See (Germany)

2016-03-15

Al{sub x}Cr{sub 1−x} composite cathodes with Al contents of x = 0.75, 0.5, and 0.25 were exposed to cathodic arc plasmas in Ar, N{sub 2}, and O{sub 2} atmospheres and their erosion behavior was studied. Cross-sectional analysis of the elemental distribution of the near-surface zone in the cathodes by scanning electron microscopy revealed the formation of a modified layer for all cathodes and atmospheres. Due to intermixing of Al and Cr in the heat-affected zone, intermetallic Al-Cr phases formed as evidenced by x-ray diffraction analysis. Cathode poisoning effects in the reactive N{sub 2} and O{sub 2} atmospheres were nonuniform as a result of the applied magnetic field configuration. With the exception of oxide islands on Al-rich cathodes, reactive layers were absent in the circular erosion zone, while nitrides and oxides formed in the less eroded center region of the cathodes.

Synopsis of Cathode No.4 Activation

International Nuclear Information System (INIS)

Kwan, Joe; Ekdahl, C.; Harrison, J.; Kwan, J.; Leitner, M.; McCruistian, T.; Mitchell, R.; Prichard, B.; Roy, P.

2006-01-01

The purpose of this report is to describe the activation of the fourth cathode installed in the DARHT-II Injector. Appendices have been used so that an extensive amount of data could be included without danger of obscuring important information contained in the body of the report. The cathode was a 612 M type cathode purchased from Spectra-Mat. Section II describes the handling and installation of the cathode. Section III is a narrative of the activation based on information located in the Control Room Log Book supplemented with time plots of pertinent operating parameters. Activation of the cathode was performed in accordance with the procedure listed in Appendix A. The following sections provide more details on the total pressure and constituent partial pressures in the vacuum vessel, cathode heater power/filament current, and cathode temperature

Quantification of Tissue Trauma following Insulin Pen Needle Insertions in Skin

DEFF Research Database (Denmark)

Jensen, Casper Bo; Larsen, Rasmus; Vestergaard, Jacob Schack

Objective: Within the field of pen needle development, most research on needle design revolves around mechanical tensile testing and patient statements. Only little has been published on the actual biological skin response to needle insertions. The objective of this study was to develop a computa......Objective: Within the field of pen needle development, most research on needle design revolves around mechanical tensile testing and patient statements. Only little has been published on the actual biological skin response to needle insertions. The objective of this study was to develop...... a computational method to quantify tissue trauma based on skin bleeding and immune response. Method: Two common sized pen needles of 28G (0.36mm) and 32G (0.23mm) were inserted into skin of sedated LYD pigs prior to termination. Four pigs were included and a total of 32 randomized needle insertions were conducted...... diameter. Conclusion: A computational and quantitative method has been developed to assess tissue trauma following insulin pen needle insertions. Application of the method is tested by conduction of a needle diameter study. The obtained quantitative measures of tissue trauma correlate positively to needle...

Microstructural control over soluble pentacene deposited by capillary pen printing for organic electronics.

Science.gov (United States)

Lee, Wi Hyoung; Min, Honggi; Park, Namwoo; Lee, Junghwi; Seo, Eunsuk; Kang, Boseok; Cho, Kilwon; Lee, Hwa Sung

2013-08-28

Research into printing techniques has received special attention for the commercialization of cost-efficient organic electronics. Here, we have developed a capillary pen printing technique to realize a large-area pattern array of organic transistors and systematically investigated self-organization behavior of printed soluble organic semiconductor ink. The capillary pen-printed deposits of organic semiconductor, 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS_PEN), was well-optimized in terms of morphological and microstructural properties by using ink with mixed solvents of chlorobenzene (CB) and 1,2-dichlorobenzene (DCB). Especially, a 1:1 solvent ratio results in the best transistor performances. This result is attributed to the unique evaporation characteristics of the TIPS_PEN deposits where fast evaporation of CB induces a morphological evolution at the initial printed position, and the remaining DCB with slow evaporation rate offers a favorable crystal evolution at the pinned position. Finally, a large-area transistor array was facilely fabricated by drawing organic electrodes and active layers with a versatile capillary pen. Our approach provides an efficient printing technique for fabricating large-area arrays of organic electronics and further suggests a methodology to enhance their performances by microstructural control of the printed organic semiconducting deposits.

A flexible approach to light pen calibration for a monocular-vision-based coordinate measuring system

International Nuclear Information System (INIS)

Fu, Shuai; Zhang, Liyan; Ye, Nan; Liu, Shenglan; Zhang, WeiZhong

2014-01-01

A monocular-vision-based coordinate measuring system (MVB-CMS) obtains the 3D coordinates of the probe tip center of a light pen by analyzing the monocular image of the target points on the light pen. The light pen calibration, including the target point calibration and the probe tip center calibration, is critical to guarantee the accuracy of the MVB-CMS. The currently used method resorts to special equipment to calibrate the feature points on the light pen in a separate offsite procedure and uses the system camera to calibrate the probe tip center onsite. Instead, a complete onsite light pen calibration method is proposed in this paper. It needs only several auxiliary target points with the same visual features of the light pen targets and two or more cone holes with known distance(s). The target point calibration and the probe tip center calibration are jointly implemented by simply taking two groups of images of the light pen with the camera of the system. The proposed method requires no extra equipment other than the system camera for the calibration, so it is easier to implement and flexible for use. It has been incorporated in a large field-of-view MVB-CMS, which uses active luminous infrared LEDs as the target points. Experimental results demonstrate the accuracy and effectiveness of the proposed method. (paper)

Cathode characterization system: preliminary results with (Ba,Sr,Ca) O coated cathodes

International Nuclear Information System (INIS)

Nono, M.C.A.; Goncalves, J.A.N.; Barroso, J.J.; Dallaqua, R.S.; Spassovsky, I.

1993-01-01

The performance of a cathode characterization system for studying the emission parameters of thermal electron emitters is reported. The system consists of vacuum chamber, power supplies and equipment for measuring and control. Measurements have been taken of the emission current as function of cathode temperature and anode voltage. Several (Ba, Sr) O coated cathodes were tested and the results have shown good agreement with Child's and Richardson's laws. The experimental work function is between 1.0 and 2.0 e V. All emission parameters measured are consistent with international literature data. (author)

Research on an improved explosive emission cathode

International Nuclear Information System (INIS)

Liu Guozhi; Sun Jun; Shao Hao; Chen Changhua; Zhang Xiaowei

2009-01-01

This paper presents a physical description of the cathode plasma process of an explosive emission cathode (EEC) and experimental results on a type of oil-immersed graphite EEC. It is believed that the generation of a cathode plasma is mainly dependent on the state of the cathode surface, and that adsorbed gases and dielectrics on the cathode surface play a leading role in the formation of the cathode plasma. Based on these ideas, a type of oil-immersed graphite EEC is proposed and fabricated. The experiments indicate that the oil-immersed cathodes have improved emissive properties and longer lifetimes.

(Anti)hydrogen recombination studies in a nested Penning trap

International Nuclear Information System (INIS)

Quint, W.; Kaiser, R.; Hall, D.; Gabrielse, G.

1993-01-01

Extremely cold antiprotons, stored in Penning trap at 4 K, open the way toward the production and study of cold antihydrogen. We have begun experimentally investigating the possibility to recombine cold positrons and antiprotons within nested Penning traps. Trap potentials are adjusted to allow cold trapped protons (and positive helium ions) to pass through cold trapped electrons. Electrons, protons and ions are counted by ejecting them to a cold channel plate and by nondestructive radiofrequency techniques. The effect of the space charge of one trapped species upon another trapped species passing through is clearly observed. (orig.)

III. Penning ionization, associative ionization and chemi-ionization processes

International Nuclear Information System (INIS)

Cermak, V.

1975-01-01

Physical mechanisms of three important ionization processes in a cold plasma and the methods of their experimental study are discussed. An apparatus for the investigation of the Penning ionization using ionization processes of long lived metastable rare gas atoms is described. Methods of determining interaction energies and ionization rates from the measured energy spectra of the originating electrons are described and illustrated by several examples. Typical associative ionization processes are listed and the ionization rates are compared with those of the Penning ionization. Interactions with short-lived excited particles and the transfer of excitation without ionization are discussed. (J.U.)

Smartphone Versus Pen-and-Paper Data Collection of Infant Feeding Practices in Rural China

Science.gov (United States)

Zhang, Shuyi; Wu, Qiong; van Velthoven, Michelle HMMT; Chen, Li; Car, Josip; Rudan, Igor; Li, Ye; Scherpbier, Robert W

2012-01-01

Background Maternal, Newborn, and Child Health (MNCH) household survey data are collected mainly with pen-and-paper. Smartphone data collection may have advantages over pen-and-paper, but little evidence exists on how they compare. Objective To compare smartphone data collection versus the use of pen-and-paper for infant feeding practices of the MNCH household survey. We compared the two data collection methods for differences in data quality (data recording, data entry, open-ended answers, and interrater reliability), time consumption, costs, interviewers’ perceptions, and problems encountered. Methods We recruited mothers of infants aged 0 to 23 months in four village clinics in Zhaozhou Township, Zhao County, Hebei Province, China. We randomly assigned mothers to a smartphone or a pen-and-paper questionnaire group. A pair of interviewers simultaneously questioned mothers on infant feeding practices, each using the same method (either smartphone or pen-and-paper). Results We enrolled 120 mothers, and all completed the study. Data recording errors were prevented in the smartphone questionnaire. In the 120 pen-and-paper questionnaires (60 mothers), we found 192 data recording errors in 55 questionnaires. There was no significant difference in recording variation between the groups for the questionnaire pairs (P = .32) or variables (P = .45). The smartphone questionnaires were automatically uploaded and no data entry errors occurred. We found that even after double data entry of the pen-and-paper questionnaires, 65.0% (78/120) of the questionnaires did not match and needed to be checked. The mean duration of an interview was 10.22 (SD 2.17) minutes for the smartphone method and 10.83 (SD 2.94) minutes for the pen-and-paper method, which was not significantly different between the methods (P = .19). The mean costs per questionnaire were higher for the smartphone questionnaire (¥143, equal to US $23 at the exchange rate on April 24, 2012) than for the pen

penORNL: a parallel Monte Carlo photon and electron transport package using PENELOPE

International Nuclear Information System (INIS)

Bekar, Kursat B.; Miller, Thomas Martin; Patton, Bruce W.; Weber, Charles F.

2015-01-01

The parallel Monte Carlo photon and electron transport code package penORNL was developed at Oak Ridge National Laboratory to enable advanced scanning electron microscope (SEM) simulations on high-performance computing systems. This paper discusses the implementations, capabilities and parallel performance of the new code package. penORNL uses PENELOPE for its physics calculations and provides all available PENELOPE features to the users, as well as some new features including source definitions specifically developed for SEM simulations, a pulse-height tally capability for detailed simulations of gamma and x-ray detectors, and a modified interaction forcing mechanism to enable accurate energy deposition calculations. The parallel performance of penORNL was extensively tested with several model problems, and very good linear parallel scaling was observed with up to 512 processors. penORNL, along with its new features, will be available for SEM simulations upon completion of the new pulse-height tally implementation.

A Rapid and Sensitive Assay for the Detection of Benzylpenicillin (PenG in Milk.

Directory of Open Access Journals (Sweden)

Anna Pennacchio

Full Text Available Antibiotics, such as benzyl-penicillin (PenG and cephalosporin, are the most common compounds used in animal therapy. Their massive and illegal use in animal therapy and prophylaxis inevitably causes the presence of traces in foods of animal origin (milk and meat, which creates several problems for human health. With the aim to prevent the negative impact of β-lactam and, in particular, PenG residues present in the milk on customer health, many countries have established maximum residue limits (MRLs. To cope with this problem here, we propose an effective alternative, compared to the analytical methods actually employed, to quantify the presence of penicillin G using the surface plasmon resonance (SPR method. In particular, the PenG molecule was conjugated to a protein carrier to immunize a rabbit and produce polyclonal antibodies (anti-PenG. The produced antibodies were used as molecular recognition elements for the design of a competitive immune-assay for the detection of PenG by SPR experiments. The detection limit of the developed assay was found to be 8.0 pM, a value much lower than the MRL of the EU regulation limit that is fixed at 12 nM. Thus, our results clearly show that this system could be successfully suitable for the accurate and easy determination of PenG.

[Preference for etanercept pen versus syringe in patients with chronic arthritis. Nurse education workshop].

Science.gov (United States)

Garcia-Diaz, Silvia; Girabent-Farrés, Montserrat; Roig-Vilaseca, Daniel; Reina, Delia; Cerdà, Dacia; González, Marina; Torrente-Segarra, Vicenç; Fíguls, Ramon; Corominas, Hèctor

2013-01-01

The aims of this study are to evaluate the level of fear of post-injection pain prior to the administration, the difficulty in handling the device, and the level of satisfaction of patients using a pre-filled syringe versus an etanercept pen, as well as to evaluate the usefulness of the training given by nursing staff prior to starting with the pen, and the preferences of patients after using both devices. A prospective study was designed to follow-up a cohort of patients during a 6 months period. The data was collected using questionnaires and analyzed with SPSS 18.00. Rank and McNemar tests were performed. Statistical significance was pre-set at an α level of 0.05. A total of 29 patients were included, of whom 69% female, and with a mean age 52.5±10.9 years. Of these, 48% had rheumatoid arthritis, 28% psoriatic arthritis, 21% ankylosing spondylitis, and 3% undifferentiated spondyloarthropathy. There were no statistically significant differences either with the fear or pain or handling of the device between the syringe and the pen (P=.469; P=.812; P=.169 respectively). At 6 months, 59% of patients referred to being satisfied or very satisfied with the pen. Almost all (93%) found useful or very useful the training given by nursing staff prior to using the pen, and 55% preferred the pen over the pre-filled syringe. The etanercept pen is another subcutaneous device option for patients with chronic arthritis. According to the present study, nursing educational workshops before starting this therapy are recommended. Copyright © 2012 Elsevier España, S.L. All rights reserved.

Novel dip-pen nanolithography strategies for nanopatterning

NARCIS (Netherlands)

Wu, C.C.

2010-01-01

Dip-pen nanolithography (DPN) is an atomic force microscopy (AFM)-based lithography technique offering the possibility of fabricating patterns with feature sizes ranging from micrometers to tens of nanometers, utilizing either top-down or bottom-up strategies. Although during its early development

Air humidity and water pressure effects on the performance of air-cathode microbial fuel cell cathodes

KAUST Repository

Ahn, Yongtae

2014-02-01

To better understand how air cathode performance is affected by air humidification, microbial fuel cells were operated under different humidity conditions or water pressure conditions. Maximum power density decreased from 1130 ± 30 mW m-2 with dry air to 980 ± 80 mW m -2 with water-saturated air. When the cathode was exposed to higher water pressures by placing the cathode in a horizontal position, with the cathode oriented so it was on the reactor bottom, power was reduced for both with dry (1030 ± 130 mW m-2) and water-saturated (390 ± 190 mW m-2) air. Decreased performance was partly due to water flooding of the catalyst, which would hinder oxygen diffusion to the catalyst. However, drying used cathodes did not improve performance in electrochemical tests. Soaking the cathode in a weak acid solution, but not deionized water, mostly restored performance (960 ± 60 mW m-2), suggesting that there was salt precipitation in the cathode that was enhanced by higher relative humidity or water pressure. These results showed that cathode performance could be adversely affected by both flooding and the subsequent salt precipitation, and therefore control of air humidity and water pressure may need to be considered for long-term MFC operation. © 2013 Elsevier B.V. All rights reserved.

Using a Computer Module to Teach Use of the EpiPen®

Directory of Open Access Journals (Sweden)

Amandeep Singh Rai

2011-11-01

Full Text Available Background: The medical literature suggests that patients and physicians are deficient in their ability to use a self-injectable epinephrine device (EpiPen® for management of anaphylaxis. This study aims to determine whether a computer module is an effective tool for the instruction of a technical skill to medical trainees. Methods: We conducted a two group comparison study of 35 Post-Graduate Year 1 and 2 Family Medicine residents. Participants were instructed on use of the EpiPen® using either a written module or a computer module. Participants were evaluated on use of the EpiPen® using standardized objective outcome measures by a blinded assessor. Assessments took place prior to and following instruction, using the assigned learning modality. Results: There were 34 participants who completed the study. Both groups demonstrated significant improvement in demonstrating use of the EpiPen® following training (p <0.001 for both. A significant post-training difference favouring the computer module learners over the written module learners was observed (p = 0.035. However, only 53% and 18% of candidates (computer module and written module, respectively were able to correctly perform all of the checklist steps. Conclusion: While our findings suggest computer modules represent an effective modality for teaching use of the EpiPen® to medical trainees, the low number of candidates who were able to perform all the checklist items regardless of modality needs to be addressed.

Cathode material for lithium batteries

Science.gov (United States)

Park, Sang-Ho; Amine, Khalil

2013-07-23

A method of manufacture an article of a cathode (positive electrode) material for lithium batteries. The cathode material is a lithium molybdenum composite transition metal oxide material and is prepared by mixing in a solid state an intermediate molybdenum composite transition metal oxide and a lithium source. The mixture is thermally treated to obtain the lithium molybdenum composite transition metal oxide cathode material.

Cathode erosion in a high-pressure high-current arc: calculations for tungsten cathode in a free-burning argon arc

International Nuclear Information System (INIS)

Nemchinsky, Valerian

2012-01-01

The motion of an evaporated atom of the cathode material in a near-cathode plasma is considered. It is shown that the evaporated atom is ionized almost instantly. The created ion, under the influence of a strong electric field existing in the cathode proximity, has a high probability of returning to the cathode. A small fraction of evaporated atoms are able to diffuse away from the cathode to the region where they are involved in plasma flow and lose their chance to return to the cathode. The fraction of the total evaporated atoms, which do not return to the cathode, the escape factor, determines the net erosion rate. In order to calculate this factor, the distributions of the plasma parameters in the near-cathode plasma were considered. Calculations showed that the escape factor is on the order of a few per cent. Using experimental data on the plasma and cathode temperatures, we calculated the net erosion rate for a free-burning 200 A argon arc with a thoriated tungsten cathode. The calculated erosion rate is close to 1 µg s -1 , which is in agreement with available experimental data. (paper)

The effect of cathode geometry on barium transport in hollow cathode plasmas

International Nuclear Information System (INIS)

Polk, James E.; Mikellides, Ioannis G.; Katz, Ira; Capece, Angela M.

2014-01-01

The effect of barium transport on the operation of dispenser hollow cathodes was investigated in numerical modeling of a cathode with two different orifice sizes. Despite large differences in cathode emitter temperature, emitted electron current density, internal xenon neutral and plasma densities, and size of the plasma-surface interaction region, the barium transport in the two geometries is qualitatively very similar. Barium is produced in the insert and flows to the surface through the porous structure. A buildup of neutral Ba pressure in the plasma over the emitter surface can suppress the reactions supplying the Ba, restricting the net production rate. Neutral Ba flows into the dense Xe plasma and has a high probability of being ionized at the periphery of this zone. The steady state neutral Ba density distribution is determined by a balance between pressure gradient forces and the drag force associated with collisions between neutral Ba and neutral Xe atoms. A small fraction of the neutral Ba is lost upstream. The majority of the neutral Ba is ionized in the high temperature Xe plasma and is pushed back to the emitter surface by the electric field. The steady state Ba + ion density distribution results from a balance between electrostatic and pressure forces, neutral Xe drag and Xe + ion drag with the dominant forces dependent on location in the discharge. These results indicate that hollow cathodes are very effective at recycling Ba within the discharge and therefore maintain a high coverage of Ba on the emitter surface, which reduces the work function and sustains high electron emission current densities at moderate temperatures. Barium recycling is more effective in the cathode with the smaller orifice because the Ba is ionized in the dense Xe plasma concentrated just upstream of the orifice and pushed back into the hollow cathode. Despite a lower emitter temperature, the large orifice cathode has a higher Ba loss rate through the orifice because the Xe

Beam Current Increase and Cathode Lifetime Improvement of KOTRON-13 Ion Source

International Nuclear Information System (INIS)

Lee, W. K.; Chae, S. K.; Song, J. Y.; Im, G. S.; Cho, B. O.

2010-01-01

Technology of cyclotron has been actively developed to meet the increasing requirement output of medical radioactive isotopes for PET. KOTRON-13 is produced with low negative hydrogen ion beam current owing to the low efficiency of proton beam current compared with foreign cyclotron. In the defect there from, the lifetime of cathode is around 5,000min, which requires frequent maintenance period, and the target beam current is maximum 50uA at a poor efficiency compared with the inflow quantity of hydrogen gas and that of inflicting arc current. Considering above affairs, we have to improve the PIG ion source extraction efficiency of KOTRON-13 in order to lift beam current. Mostly the ion source of cyclotron less than 30Mev comes from the use of PIG ion source mainly with the method of cold cathode or hot cathode. However, the cyclotron of 30Mev grade of EBCO or IBA uses the external ion source and uses ion source with cusp type of good withdrawal efficiency. This type requires high voltage, and transports ion from ion source to cyclotron, which requires precise transportation equipment. And entering cyclotron requires a high quality of inflictor with a high defect rate, but high current cyclotron has no choice but to use ion source of such a method. But the cyclotron using PET with the beam current less than 100uA uses PIG ion source of KOTRON-13 with a reasonable maintenance cost

Extending Penning trap mass measurements with SHIPTRAP to the heaviest elements

International Nuclear Information System (INIS)

Block, M.; Ackermann, D.; Herfurth, F.; Hofmann, S.; Blaum, K.; Droese, C.; Marx, G.; Schweikhard, L.; Düllmann, Ch. E.; Eibach, M.; Eliseev, S.; Haettner, E.; Plaß, W. R.; Scheidenberger, C.; Heßberger, F. P.; Ramirez, E. Minaya; Nesterenko, D.

2013-01-01

Penning-trap mass spectrometry of radionuclides provides accurate mass values and absolute binding energies. Such mass measurements are sensitive indicators of the nuclear structure evolution far away from stability. Recently, direct mass measurements have been extended to the heavy elements nobelium (Z=102) and lawrencium (Z=103) with the Penning-trap mass spectrometer SHIPTRAP. The results probe nuclear shell effects at N=152. New developments will pave the way to access even heavier nuclides.

CrossRef Space-charge effects in Penning ion traps

CERN Document Server

Porobić, T; Breitenfeldt, M; Couratin, C; Finlay, P; Knecht, A; Fabian, X; Friedag, P; Fléchard, X; Liénard, E; Ban, G; Zákoucký, D; Soti, G; Van Gorp, S; Weinheimer, Ch; Wursten, E; Severijns, N

2015-01-01

The influence of space-charge on ion cyclotron resonances and magnetron eigenfrequency in a gas-filled Penning ion trap has been investigated. Off-line measurements with View the MathML source using the cooling trap of the WITCH retardation spectrometer-based setup at ISOLDE/CERN were performed. Experimental ion cyclotron resonances were compared with ab initio Coulomb simulations and found to be in agreement. As an important systematic effect of the WITCH experiment, the magnetron eigenfrequency of the ion cloud was studied under increasing space-charge conditions. Finally, the helium buffer gas pressure in the Penning trap was determined by comparing experimental cooling rates with simulations.

Cathodic protection -- Rectifier 47

International Nuclear Information System (INIS)

Lane, W.M.

1995-01-01

This Acceptance Test Procedure (ATP) has been prepared to demonstrate that the cathodic protection system functions as required by project criteria. The cathodic protection system is for the tank farms at the Hanford Reservation. The tank farms store radioactive waste

Cathodic protection -- Rectifier 46

International Nuclear Information System (INIS)

Lane, W.M.

1995-01-01

This Acceptance Test Procedure (ATP) has been prepared to demonstrate that the cathodic protection system functions as required by project criteria. The cathodic protection system is for the tank farms on the Hanford Reservation. The tank farms store radioactive waste

Effects of lignite application on ammonia and nitrous oxide emissions from cattle pens

Energy Technology Data Exchange (ETDEWEB)

Sun, Jianlei, E-mail: su@unimelb.edu.au [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia); Bai, Mei [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia); Shen, Jianlin [Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha 410125 (China); Griffith, David W.T. [Department of Chemistry, University of Wollongong, NSW 2522 (Australia); Denmead, Owen T. [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia); Hill, Julian [Ternes Agricultural Consulting Pty Ltd, Upwey, VIC 3158 (Australia); Lam, Shu Kee; Mosier, Arvin R. [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia); Chen, Deli, E-mail: delichen@unimelb.edu.au [Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010 (Australia)

2016-09-15

Beef cattle feedlots are a major source of ammonia (NH{sub 3}) emissions from livestock industries. We investigated the effects of lignite surface applications on NH{sub 3} and nitrous oxide (N{sub 2}O) emissions from beef cattle feedlot pens. Two rates of lignite, 3 and 6 kg m{sup −2}, were tested in the treatment pen. No lignite was applied in the control pen. Twenty-four Black Angus steers were fed identical commercial rations in each pen. We measured NH{sub 3} and N{sub 2}O concentrations continuously from 4th Sep to 13th Nov 2014 using Quantum Cascade Laser (QCL) NH{sub 3} analysers and a closed-path Fourier Transform Infrared Spectroscopy analyser (CP-FTIR) in conjunction with the integrated horizontal flux method to calculate NH{sub 3} and N{sub 2}O fluxes. During the feeding period, 16 and 26% of the excreted nitrogen (N) (240 g N head{sup −1} day{sup −1}) was lost via NH{sub 3} volatilization from the control pen, while lignite application decreased NH{sub 3} volatilization to 12 and 18% of the excreted N, for Phase 1 and Phase 2, respectively. Compared to the control pen, lignite application decreased NH{sub 3} emissions by approximately 30%. Nitrous oxide emissions from the cattle pens were small, 0.10 and 0.14 g N{sub 2}O-N head{sup −1} day{sup −1} (< 0.1% of excreted N) for the control pen, for Phase 1 and Phase 2, respectively. Lignite application increased direct N{sub 2}O emissions by 40 and 57%, to 0.14 and 0.22 g N{sub 2}O-N head{sup −1} day{sup −1}, for Phase 1 and Phase 2, respectively. The increase in N{sub 2}O emissions resulting from lignite application was counteracted by the lower indirect N{sub 2}O emission due to decreased NH{sub 3} volatilization. Using 1% as a default emission factor of deposited NH{sub 3} for indirect N{sub 2}O emissions, the application of lignite decreased total N{sub 2}O emissions. - Graphical abstract: Lignite application substantially decreased NH{sub 3} emissions from cattle feedlots and increased

Cathode R&D for Future Light Sources

Energy Technology Data Exchange (ETDEWEB)

Dowell, D.H.; /SLAC; Bazarov, I.; Dunham, B.; /Cornell U., CLASSE; Harkay, K.; /Argonne; Hernandez-Garcia; /Jefferson Lab; Legg, R.; /Wisconsin U., SRC; Padmore, H.; /LBL, Berkeley; Rao, T.; Smedley, J.; /Brookhaven; Wan, W.; /LBL, Berkeley

2010-05-26

This paper reviews the requirements and current status of cathodes for accelerator applications, and proposes a research and development plan for advancing cathode technology. Accelerator cathodes need to have long operational lifetimes and produce electron beams with a very low emittance. The two principal emission processes to be considered are thermionic and photoemission with the photocathodes being further subdivided into metal and semi-conductors. Field emission cathodes are not included in this analysis. The thermal emittance is derived and the formulas used to compare the various cathode materials. To date, there is no cathode which provides all the requirements needed for the proposed future light sources. Therefore a three part research plan is described to develop cathodes for these future light source applications.

Mechanistic Enhancement of SOFC Cathode Durability

Energy Technology Data Exchange (ETDEWEB)

Wachsman, Eric [Univ. of Maryland, College Park, MD (United States)

2016-02-01

Durability of solid oxide fuel cells (SOFC) under “real world” conditions is an issue for commercial deployment. In particular cathode exposure to moisture, CO2, Cr vapor (from interconnects and BOP), and particulates results in long-term performance degradation issues. Here, we have conducted a multi-faceted fundamental investigation of the effect of these contaminants on cathode performance degradation mechanisms in order to establish cathode composition/structures and operational conditions to enhance cathode durability.

Two-beam virtual cathode accelerator

International Nuclear Information System (INIS)

Peter, W.

1992-01-01

A proposed method to control the motion of a virtual cathode is investigated. Applications to collective ion acceleration and microwave generation are indicated. If two counterstreaming relativistic electron beams of current I are injected into a drift tube of space-charge-limiting current I L = 2I, it is shown that one beam can induce a moving virtual cathode in the other beam. By dynamically varying the current injected into the drift tube region, the virtual cathode can undergo controlled motion. For short drift tubes, the virtual cathodes on each end are strongly-coupled and undergo coherent large-amplitude spatial oscillations within the drift tube

Electron emission from pseudospark cathodes

International Nuclear Information System (INIS)

Anders, A.; Anders, S.; Gundersen, M.A.

1994-01-01

The pseudospark cathode has the remarkable property of macroscopically homogeneous electron emission at very high current density (>1 kA/cm 2 ) over a large area (some cm 2 ). The model of electron emission presented here is based on the assumption that the pseudospark microscopically utilizes explosive arc processes, as distinct from earlier models of ''anomalous emission in superdense glow discharges.'' Explosive emission similar to vacuum are cathode spots occurs rapidly when the field strength is sufficiently high. The plasma remains macroscopically homogeneous since the virtual plasma anode adapts to the cathode morphology so that the current is carried by a large number of homogeneously distributed cathode spots which are similar to ''type 1'' and ''type 2'' spots of vacuum arc discharges. The net cathode erosion is greatly reduced relative to ''spark gap-type'' emission. At very high current levels, a transition to highly erosive spot types occurs, and this ''arcing'' leads to a significant reduction in device lifetime. Assuming vacuum-arc-like cathode spots, the observed current density and time constants can be easily explained. The observed cathode erosion rate and pattern, recent fast-camera data, laser-induced fluorescence, and spectroscopic measurements support this approach. A new hypothesis is presented explaining current quenching at relatively low currents. From the point of view of electron emission, the ''superdense glow'' or ''superemissive phase'' of pseudosparks represents an arc and not a glow discharge even if no filamentation or ''arcing'' is observed

Cold cathode arc model in mercury discharges

International Nuclear Information System (INIS)

Li, Y.M.; Byszewski, W.W.; Budinger, A.B.

1990-01-01

Voltage/current characteristics measured during the starting of metal halide lamps indicate a low voltage discharge when condensates (mainly mercury) are localized on the electrodes. In this case, even with a cold cathode which does not emit electrons, the current is very high and voltage across the lamp drops to about 15 to 20 V. This type of discharge is similar to the cold cathode mercury vapor arc found in mercury pool rectifiers. The cathode sheath in the mercury vapor arc is characterized by very small cathode spot size, on the order of 10 -c cm 2 , very high current density of about 10 6 A/cm 2 and very low cathode fall of approximately 10 volts. The discharge is modified and generalized to describe the cathode phenomena in the cold cathode mercury vapor arc. The sensitivity of calculated discharge parameters with respect to such modifications were examined. Results show that the cathode fall voltage remains fairly constant (7-8 volts) with large fractional variations of metastable mercury atoms bombarding the cathode. This result compares very well with experimental waveforms when anode fall and plasma voltage approximations are incorporated

Electron emission mechanism of carbon fiber cathode

International Nuclear Information System (INIS)

Liu Lie; Li Limin; Wen Jianchun; Wan Hong

2005-01-01

Models of electron emission mechanism are established concerning metal and carbon fiber cathodes. Correctness of the electron emission mechanism was proved according to micro-photos and electron scanning photos of cathodes respectively. The experimental results and analysis show that the surface flashover induces the electron emission of carbon fiber cathode and there are electron emission phenomena from the top of the carbon and also from its side surface. In addition, compared with the case of the stainless steel cathode, the plasma expansion velocity for the carbon fiber cathode is slower and the pulse duration of output microwave can be widened by using the carbon fiber cathode. (authors)

Ecosystem Pen Pals: Using Place-Based Marine Science and Culture to Connect Students

Science.gov (United States)

Wiener, Carlie S.; Matsumoto, Karen

2014-01-01

The marine environment provides a unique context for students to explore both natural and cultural connections. This paper reports preliminary findings on Ecosystem Pen Pals, an ocean literacy program for 4th and 5th graders focused on using a pen pal model for integrating traditional ecological knowledge into marine science. Surveys with…

Flexible AMOLED display on polyethylene napthalate (PEN) foil with metal-oxide TFT backplane

NARCIS (Netherlands)

Tripathi, A.K.; Putten, B. van der; Steen, J.L. van der; Tempelaars, K.; Cobb, B.; Ameys, M.; Ke, T.H.; Myny, K.; Steudel, S.; Nag, M.; Schols, S.; Vicca, P.; Smout, S.; Genoe, J.; Heremans, P.; Yakimets, I.; Gelinck, G.H.

2012-01-01

We present a top emitting monochrome AMOLED display with 85dpi resolution using an amorphous Indium-Gallium-Zinc-Oxide (IGZO) TFT backplane on PEN-foil. Maximum processing temperature was limited to 150 °C in order to ensure an overlay accuracy < 3μm on PEN foil. The backplane process flow is based

Studying the variability in the Raman signature of writing pen inks.

Science.gov (United States)

Braz, André; López-López, María; García-Ruiz, Carmen

2014-12-01

This manuscript aims to study the inter and intra brand, model and batch variability in the Raman spectral signature among modern pen inks that will help forensic document examiners during the interpretation process. Results showed that most oil-based samples have similar Raman signatures that are characteristic of the Crystal Violet dye, independently of the brand. Exception was the Pilot samples that use Victoria Pure Blue BO instead. This small inter-brand variability makes oil-based pens difficult to discriminate by brand. On the contrary, gel and liquid-based samples use different colorants such as Rhodamine B, Copper Phthalocyanine, Ethyl Violet and Victoria Blue B. No particular pattern was observed regarding the colorants used by each brand, except the Pilot samples that were the only brand using the Victoria Blue B dye, which is a clear distinct feature. Additionally, the intra-brand variability was also large among gel-based Pilot samples. The small spectral differences observed among several batches of Bic Crystal Medium samples demonstrated that changes were introduced in their chemical formula over the years. The intra-batch variability was small and no spectral differences were observed within batches. This manuscript demonstrates the potential of Raman spectroscopy for discriminating pens inks from different brands and models and even, batches. Additionally, the main colorants used in modern pens were also identified. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Direct current-induced electrogenerated chemiluminescence of hydrated and chelated Tb(III) at aluminum cathodes

International Nuclear Information System (INIS)

Hakansson, M.; Jiang, Q.; Spehar, A.-M.; Suomi, J.; Kotiranta, M.; Kulmala, S.

2005-01-01

Cathodic DC polarization of oxide-covered aluminum produces electrogenerated chemiluminescence from hydrated and chelated Tb(III) ions in aqueous electrolyte solutions. At the moment of cathodic voltage onset, a strong cathodic flash is observed, which is attributed to a tunnel emission of hot electrons into the aqueous electrolyte solution and the successive chemical reactions with the luminophores. However, within a few milliseconds the insulating oxide film is damaged and finally dissolved due to (i) indiffusion of protons or alkali metal ions into the thin oxide film, (ii) subsequent hydrogen evolution at the aluminum/oxide interface and (iii) alkalization of the electrode surface induced by hydrogen evolution reaction. When the alkalization of the electrode surface has proceeded sufficiently, chemiluminescence is generated with increasing intensity. Aluminum metal, short-lived Al(II), Al(I) or atomic hydrogen and its conjugated base form, hydrated electron, can act as highly reducing species in addition to the less energetic heterogeneously transferred electrons from the aluminum electrode. Tb(III) added as a hydrated ion in the solution probably luminesces in the form of Tb(OH) 3 or Tb(OH) 4 - by direct redox reactions of the central ion whereas multidentate aromatic ligand chelated Tb(III) probably luminesces by ligand sensitized chemiluminescence mechanism in which ligand is first excited by one-electron redox reactions, which is followed by intramolecular energy transfer to the central ion which finally emits light

Plasma processes inside dispenser hollow cathodes

International Nuclear Information System (INIS)

Mikellides, Ioannis G.; Katz, Ira; Goebel, Dan M.; Polk, James E.; Jameson, Kristina K.

2006-01-01

A two-dimensional fluid model of the plasma and neutral gas inside dispenser orificed hollow cathodes has been developed to quantify plasma processes that ultimately determine the life of the porous emitters inserted in these devices. The model self-consistently accounts for electron emission from the insert as well as for electron and ion flux losses from the plasma. Two cathodes, which are distinctively different in size and operating conditions, have been simulated numerically. It is found that the larger cathode, with outer tube diameter of 1.5 cm and orifice diameter of 0.3 cm, establishes an effective emission zone that spans approximately the full length of the emitter when operated at a discharge current of 25 A and a flow rate of 5.5 sccm. The net heating of the emitter is caused by ions that are produced by ionization of the neutral gas inside the tube and are then accelerated by the sheath along the emitter. The smaller cathode, with an outer diameter of 0.635 cm and an orifice diameter of 0.1 cm, does not exhibit the same operational characteristics. At a flow rate of 4.25 sccm and discharge current of 12 A, the smaller cathode requires 4.5 times the current density near the orifice and operates with more than 6 times the neutral particle density compared to the large cathode. As a result, the plasma particle density is almost one order of magnitude higher compared to the large cathode. The plasma density in this small cathode is high enough such that the Debye length is sufficiently small to allow 'sheath funneling' into the pores of the emitter. By accessing areas deeper into the insert material, it is postulated that the overall emission of electrons is significantly enhanced. The maximum emission current density is found to be about 1 A/mm 2 in the small cathode, which is about one order of magnitude higher than attained in the large cathode. The effective emission zone in the small cathode extends to about 15% of the emitter length only, and the

Electrospray deposition from fountain pen AFM probes

NARCIS (Netherlands)

Geerlings, J.; Sarajlic, Edin; Berenschot, Johan W.; Abelmann, Leon; Tas, Niels Roelof

2012-01-01

In this paper we present for the first time electrospraying from fountain pen probes. By using electrospray contactless deposition in an AFM setup becomes possible. Experiments on a dedicated setup were carried out as first step towards this goal. Spraying from 8 and 2 µm apertures was observed. For

Compact Rare Earth Emitter Hollow Cathode

Science.gov (United States)

Watkins, Ronald; Goebel, Dan; Hofer, Richard

2010-01-01

A compact, high-current, hollow cathode utilizing a lanthanum hexaboride (LaB6) thermionic electron emitter has been developed for use with high-power Hall thrusters and ion thrusters. LaB6 cathodes are being investigated due to their long life, high current capabilities, and less stringent xenon purity and handling requirements compared to conventional barium oxide (BaO) dispenser cathodes. The new cathode features a much smaller diameter than previously developed versions that permit it to be mounted on axis of a Hall thruster ( internally mounted ), as opposed to the conventional side-mount position external to the outer magnetic circuit ("externally mounted"). The cathode has also been reconfigured to be capable of surviving vibrational loads during launch and is designed to solve the significant heater and materials compatibility problems associated with the use of this emitter material. This has been accomplished in a compact design with the capability of high-emission current (10 to 60 A). The compact, high-current design has a keeper diameter that allows the cathode to be mounted on the centerline of a 6- kW Hall thruster, inside the iron core of the inner electromagnetic coil. Although designed for electric propulsion thrusters in spacecraft station- keeping, orbit transfer, and interplanetary applications, the LaB6 cathodes are applicable to the plasma processing industry in applications such as optical coatings and semiconductor processing where reactive gases are used. Where current electrical propulsion thrusters with BaO emitters have limited life and need extremely clean propellant feed systems at a significant cost, these LaB6 cathodes can run on the crudest-grade xenon propellant available without impact. Moreover, in a laboratory environment, LaB6 cathodes reduce testing costs because they do not require extended conditioning periods under hard vacuum. Alternative rare earth emitters, such as cerium hexaboride (CeB6) can be used in this

Electrochemical Corrosion Behavior of Carbon Steel and Hot Dip Galvanized Steel in Simulated Concrete Solution with Different pH Values

Directory of Open Access Journals (Sweden)

Wanchen XIE

2017-08-01

Full Text Available Hot dip galvanizing technology is now widely used as a method of protection for steel rebars. The corrosion behaviors of Q235 carbon steel and hot galvanized steel in a Ca(OH2 solution with a pH from 10 to 13 was investigated by electrode potential and polarization curves testing. The results indicated that carbon steel and hot galvanized steel were all passivated in a strong alkaline solution. The electrode potential of hot dip galvanized steel was lower than that of carbon steel; thus, hot dip galvanized steel can provide very good anodic protection for carbon steel. However, when the pH value reached 12.5, a polarity reversal occurred under the condition of a certain potential. Hot dip galvanized coating became a cathode, and the corrosion of carbon steel accelerated. The electrochemical behaviors and passivation abilities of hot dip galvanized steel and carbon steel were affected by pH. The higher the pH value was, the more easily they were passivated.DOI: http://dx.doi.org/10.5755/j01.ms.23.3.16675

Preliminary study for the National Energy Plan (PEN) uses the Community market as a reference base. El ante-proyecto del Plan Energetico Nacional (PEN) toma referencia basica del mercado comunitario

Energy Technology Data Exchange (ETDEWEB)

1991-11-01

The National Energy Plan (PEN) for the period 1991 to 2000 lays down basic guidelines for a Spanish energy policy. This includes a wide range of economic measures. The PEN is divided into five main sections with two appendices. The sections are: the international situation; energy demand; energy supply; energy and the environment; and R D policy. The appendices are: Energy-saving and energy-efficiency plan; and General plan for radioactive waste. The PEN provides for 4-year research programmes which aim to reduce the environmental impact of energy production and use. General demand for energy during this period will increase by2.4% and investment in power installations and in the gas sector will be some 1.5 thousand million pesetas. 4 figs., 3 tabs.

Rap van tong, scherp van pen. Literaire discussiecultuur in Nederlandse praatjespamfletten (circa 1600-1750)

NARCIS (Netherlands)

Dingemanse, C.W.

2008-01-01

In the early modern period pamphlets constituted the most important medium to influence public opinion in the Netherlands. The thesis Rap van tong, scherp van pen (Glib tongues, sharp pens) focuses on the literary and rhetorical aspects of a remarkable type of pamphlet called praatje (small-talk),

A one-dimensional model illustrating virtual-cathode formation in a novel coaxial virtual-cathode oscillator

International Nuclear Information System (INIS)

Turner, Geoffrey R.

2014-01-01

A one-dimensional electrostatic sheet model of a coaxial geometry Virtual Cathode Oscillator (VCO) is presented. The cathode is centrally located and connects to a peripherally located plate electrode to form a resonant cavity, and is thus considered to be a novel design. Charge is modelled as concentric sheets about the cathode whose absolute position and velocity are determined as a function of time by solving the relativistic equations of motion. The model predicts the formation of a virtual cathode between the grid and plate electrodes for the case of a space-charge limited current. Setting the electron reflexing frequency (as a function of the grid potential) comparable with the cavity resonant frequency is predicted to improve the efficiency of microwave emission

A Novel Cathode Material for Cathodic Dehalogenation of 1,1-Dibromo Cyclopropane Derivatives.

Science.gov (United States)

Gütz, Christoph; Selt, Maximilian; Bänziger, Markus; Bucher, Christoph; Römelt, Christina; Hecken, Nadine; Gallou, Fabrice; Galvão, Tomás R; Waldvogel, Siegfried R

2015-09-28

Leaded bronze turned out to be an excellent cathode material for the dehalogenation reaction of cyclopropanes without affecting the strained molecular entity. With this particular alloy, beneficial properties of lead cathodes are conserved, whereas the corrosion of cathode is efficiently suppressed. The solvent in the electrolyte determines whether a complete debromination reaction is achieved or if the process can be selectively stopped at the monobromo cyclopropane intermediate. The electroorganic conversion tolerates a variety of functional groups and can be conducted at rather complex substrates like cyclosporine A. This approach allows the sustainable preparation of cyclopropane derivatives. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Role of penA polymorphisms for penicillin susceptibility in Neisseria lactamica and Neisseria meningitidis.

Science.gov (United States)

Karch, André; Vogel, Ulrich; Claus, Heike

2015-10-01

In meningococci, reduced penicillin susceptibility is associated with five specific mutations in the transpeptidase region of penicillin binding protein 2 (PBP2). We showed that the same set of mutations was present in 64 of 123 Neisseria lactamica strains obtained from a carriage study (MIC range: 0.125-2.0mg/L). The PBP2 encoding penA alleles in these strains were genetically similar to those found in intermediate resistant meningococci suggesting frequent interspecies genetic exchange. Fifty-six N. lactamica isolates with mostly lower penicillin MICs (range: 0.064-0.38mg/L) exhibited only three of the five mutations. The corresponding penA alleles were unique to N. lactamica and formed a distinct genetic clade. PenA alleles with no mutations on the other hand were unique to meningococci. Under penicillin selective pressure, genetic transformation of N. lactamica penA alleles in meningococci was only possible for alleles encoding five mutations, but not for those encoding three mutations; the transfer resulted in MICs comparable to those of meningococci harboring penA alleles that encoded PBP2 with five mutations, but considerably lower than those of the corresponding N. lactamica donor strains. Due to a transformation barrier the complete N. lactamica penA could not be transformed into N. meningitidis. In summary, penicillin MICs in N. lactamica were associated with the number of mutations in the transpeptidase region of PBP2. Evidence for interspecific genetic transfer was only observed for penA alleles associated with higher MICs, suggesting that alleles encoding only three mutations in the transpeptidase region are biologically not effective in N. meningitidis. Factors other than PBP2 seem to be responsible for the high levels of penicillin resistance in N. lactamica. A reduction of penicillin susceptibility in N. meningitidis by horizontal gene transfer from N. lactamica is unlikely to happen. Copyright © 2015 Elsevier GmbH. All rights reserved.

Neisseria gonorrhoeae and extended-spectrum cephalosporins in California: surveillance and molecular detection of mosaic penA.

Science.gov (United States)

Gose, Severin; Nguyen, Duylinh; Lowenberg, Daniella; Samuel, Michael; Bauer, Heidi; Pandori, Mark

2013-12-04

The spread of Neisseria gonorrhoeae strains with mosaic penA alleles and reduced susceptibility to extended-spectrum cephalosporins is a major public health problem. While much work has been performed internationally, little is known about the genetics or molecular epidemiology of N. gonorrhoeae isolates with reduced susceptibility to extended-spectrum cephalosporins in the United States. The majority of N. gonorrhoeae infections are diagnosed without a live culture. Molecular tools capable of detecting markers of extended-spectrum cephalosporin resistance are needed. Urethral N. gonorrhoeae isolates were collected from 684 men at public health clinics in California in 2011. Minimum inhibitory concentrations (MICs) to ceftriaxone, cefixime, cefpodoxime and azithromycin were determined by Etest and categorized according to the U.S. Centers for Disease Control 2010 alert value breakpoints. 684 isolates were screened for mosaic penA alleles using real-time PCR (RTPCR) and 59 reactive isolates were subjected to DNA sequencing of their penA alleles and Neisseria gonorrhoeae multi-antigen sequence typing (NG-MAST). To increase the specificity of the screening RTPCR in detecting isolates with alert value extended-spectrum cephalosporin MICs, the primers were modified to selectively amplify the mosaic XXXIV penA allele. Three mosaic penA alleles were detected including two previously described alleles (XXXIV, XXXVIII) and one novel allele (LA-A). Of the 29 isolates with an alert value extended-spectrum cephalosporin MIC, all possessed the mosaic XXXIV penA allele and 18 were sequence type 1407, an internationally successful strain associated with multi-drug resistance. The modified RTPCR detected the mosaic XXXIV penA allele in urethral isolates and urine specimens and displayed no amplification of the other penA alleles detected in this study. N. gonorrhoeae isolates with mosaic penA alleles and reduced susceptibility to extended-spectrum cephalosporins are currently

Pengembangan Media Ice Breaker Talking Pen pada Mata Pelajaran PAI Kelas X SMAN 100 Jakarta

Directory of Open Access Journals (Sweden)

Ati Sulastri

2017-07-01

Full Text Available This study aims to find out how to develop media ice breaker talking pen and media feasibility on the subjects of PAI. The research method used is Borg and Gall development model which includes requirement analysis, validation test, and test phase. The result of this development research is ice breaker talking pen media product which consists of command card and music developed through data collection, planning, product development, and validation and testing. Based on the validation results obtained the average score of the material experts of 4.75 (very good, and from the media experts of 3.78 (good, and the results of student responses about this media amounted to 4.39 or very good category. Therefore the ice breaker talking media on the eyes of learning PAI class X is declared eligible for use with very good category. Keywords: Development Model  Study, Ice Breaker Talking Pen, PAI Abstrak Penelitian ini bertujuan untuk mengetahui cara mengembangkan media ice breaker talking pen dan kelayakan media tersebut pada mata pelajaran PAI. Metode yang digunakan adalah model pengembangan Borg dan Gall yang meliputi analisis kebutuhan, tahap validasi dan tahap uji coba. Hasil penelitian pengembangan ini adalah produk media ice breaker talking pen yang terdiri dari kartu perintah dan musik yang dikembangkan melalui tahap pengumpulan data, perencanaan, pengembangan produk, serta validasi dan uji coba. Berdasarkan pada hasil validasi didapat skor rata-rata dari ahli materi sebesar 4,75 (sangat baik, dan dari ahli media sebesar 3,78 (baik. Serta hasil dari tanggapan siswa mengenai media ini sebesar 4,39 atau kategori sangat baik. Maka dari itu media ice breaker talking pen pada mata pelajaran PAI kelas X dinyatakan layak untuk digunakan dengan kategori sangat baik. Kata Kunci : Pengembangan Model Pembelajaran, Ice Breaker Talking Pen, PAI

Reflective article having a sacrificial cathodic layer

Science.gov (United States)

Kabagambe, Benjamin; Buchanan, Michael J.; Scott, Matthew S.; Rearick, Brian K.; Medwick, Paul A.; McCamy, James W.

2017-09-12

The present invention relates to reflective articles, such as solar mirrors, that include a sacrificial cathodic layer. The reflective article, more particularly includes a substrate, such as glass, having a multi-layered coating thereon that includes a lead-free sacrificial cathodic layer. The sacrificial cathodic layer includes at least one transition metal, such as a particulate transition metal, which can be in the form of flakes (e.g., zinc flakes). The sacrificial cathodic layer can include an inorganic matrix formed from one or more organo-titanates. Alternatively, the sacrificial cathodic layer can include an organic polymer matrix (e.g., a crosslinked organic polymer matrix formed from an organic polymer and an aminoplast crosslinking agent). The reflective article also includes an outer organic polymer coating, that can be electrodeposited over the sacrificial cathodic layer.

Geiger counters of gamma rays with a bismuth cathode; Compteurs de geiger a rayons gamma a cathode de bismuth

Energy Technology Data Exchange (ETDEWEB)

Meunier, R; Legrand, J P [Commissariat a l' Energie Atomique, Saclay(France). Centre d' Etudes Nucleaires

1953-07-01

Geiger Muller counters present a lake of efficiency of some per cent, for the {gamma} radiations. In the region 0,3 - 1 MeV, a substantial growth of their output can be obtained by a special construction of their cathode. In accordance with previous works, we constructed some counter of formed cathode by a pleated copper wire fencing covered of Bi by electrolysis. The successive modifications brought to a cylindrical conventional cathode in sheet metal of copper, that succeeds to this type of cathode, drive to an improvement of the output. (M.B.) [French] Les compteurs de Geiger Muller presentent une efficacite assez faible de l'ordre de quelques pour cent, pour les rayonnements {gamma}. Dans la region 0,3 - 1 MeV, un accroissement substantiel de leur rendement peut etre obtenu par une construction speciale de leur cathode. Conformement a des travaux anterieurs, nous avons construit des compteurs a cathode formee par un grillage de cuivre plisse recouvert de Bi par electrolyse. Les modifications successives apportees a une cathode conventionnelle cylindrique en tole de cuivre, qui aboutissent a ce type de cathode, conduisent a une amelioration du rendement. (M.B.)

Dosing Accuracy of Insulin Aspart FlexPens After Transport Through the Pneumatic Tube System.

Science.gov (United States)

Ward, Leah G; Heckman, Michael G; Warren, Amy I; Tran, Kimberly

2013-01-01

The purpose of this study was to evaluate whether transporting insulin aspart FlexPens via a pneumatic tube system affects the dosing accuracy of the pens. A total of 115 Novo Nordisk FlexPens containing insulin aspart were randomly assigned to be transported via a pneumatic tube system (n = 92) or to serve as the control (n = 23). Each pen was then randomized to 10 international unit (IU) doses (n = 25) or 30 IU doses (n = 67), providing 600 and 603 doses, respectively, for the pneumatic tube group. The control group also received random assignment to 10 IU doses (n = 6) or 30 IU doses (n = 17), providing 144 and 153 doses, respectively. Each dose was expelled using manufacturer instructions. Weights were recorded, corrected for specific gravity, and evaluated based on acceptable International Organization for Standardization (ISO) dosing limits. In the group of pens transported through the pneumatic tube system, none of the 600 doses of 10 IU (0.0%; 95% CI, 0.0 to 0.6) and none of the 603 doses of 30 IU (0.0%; 95% CI, 0.0 to 0.6) fell outside of the range of acceptable weights. Correspondingly, in the control group, none of the 144 doses at 10 IU (0.0%; 95% CI, 0.0 to 2.5) and none of the 153 doses at 30 IU (0.0%; 95% CI, 0.0 to 2.4) were outside of acceptable ISO limits. Transportation via pneumatic tube system does not appear to compromise dosing accuracy. Hospital pharmacies may rely on the pneumatic tube system for timely and accurate transport of insulin aspart FlexPens.

The effect of sex, slaughter weight and weight gains in PEN-AR-LAN ...

African Journals Online (AJOL)

The aim of the study was to determine the effect of sex, body weight and growth rates on basic fattening and slaughter indexes in PEN-AR-LAN fatteners. The research was conducted on 274 PEN-ARLAN hybrid fatteners coming from sows of the Naïma maternal line and was sired by boars of the P-76 meat line. Recorded ...

An experimental study of molten salt electrorefining of uranium using solid iron cathode and liquid cadmium cathode for development of pyrometallurgical reprocessing

International Nuclear Information System (INIS)

Koyama, Tadafumi; Iizuka, Masatoshi; Tanaka, Hiroshi; Tokiwai, Moriyasu; Shoji, Yuichi; Fujita, Reiko; Kobayashi, Tsuguyuki.

1997-01-01

Electrorefining of uranium was studied for developing pyrometallurgical reprocessing technology of metal fuel cycle. After concentration dependence of polarization curve was measured, uranium was electrodeposited either on solid iron cathode or in liquid cadmium cathode. Design and operational conditions of the cathode were improved for obtaining much greater quantity of deposit, resulting in recovery of 732g of dendritic uranium on a single solid cathode, and of 232g of uranium in 2,344g of a liquid cadmium cathode. The behaviors of electro-codeposition of rare earth elements with uranium were observed for liquid cadmium cathode, and were found to follow the local equilibrium between salt electrolyte and cathode. The decontamination factors of FP simulating elements from uranium were tentatively determined as >2,000 for deposition to solid cathode and as >7 for deposition to liquid cadmium cathode, respectively. (author)

Predictors of death and production performance of layer chickens in opened and sealed pens in a tropical savannah environment.

Science.gov (United States)

Shittu, Aminu; Raji, Abdullahi Abdullahi; Madugu, Shuaibu A; Hassan, Akinola Waheed; Fasina, Folorunso Oludayo

2014-09-12

Layer chickens are exposed to high risks of production losses and mortality with impact on farm profitability. The harsh tropical climate and severe disease outbreaks, poor biosecurity, sub-minimal vaccination and treatment protocols, poor management practices, poor chick quality, feed-associated causes, and unintended accidents oftentimes aggravate mortality and negatively affect egg production. The objectives of this study were to estimate the probability of survival and evaluate risk factors for death under different intensive housing conditions in a tropical climate, and to assess the production performance in the housing systems. Daily mean mortality percentages and egg production figures were significantly lower and higher in the sealed pens and open houses (P ratio for mortality of layers raised in sealed pens was 0.568 (56.8%). Reasons for spiked mortality in layer chickens may not always be associated with disease. Hot-dry climatic environment is associated with heat stress, waning immunity and inefficient feed usage and increase probability of death with reduced egg production; usage of environmentally controlled building in conditions where environmental temperature may rise significantly above 25°C will reduce this impact. Since younger birds (19-38 weeks) are at higher risk of death due to stress of coming into production, management changes and diseases, critical implementation of protocols that will reduce death at this precarious period becomes mandatory. Whether older chickens' better protection from death is associated with many prophylactic and metaphylactic regimen of medications/vaccination will need further investigation.

Cathode R and D for future light sources

Energy Technology Data Exchange (ETDEWEB)

Dowell, D.H., E-mail: dowell@slac.stanford.ed [SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA 94025 (United States); Bazarov, I.; Dunham, B. [Cornell University, Cornell Laboratory for Accelerator-Based Sciences and Education (CLASSE) Wilson Laboratory, Cornell University, Ithaca, NY 14853 (United States); Harkay, K. [Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Il 60439 (United States); Hernandez-Garcia, C. [Thomas Jefferson Laboratory, 12000 Jefferson Ave, Free Electron Laser Suite 19 Newport News, VA 23606 (United States); Legg, R. [University of Wisconsin, SRC, 3731 Schneider Dr., Stoughton, WI 53589 (United States); Padmore, H. [Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720 (United States); Rao, T.; Smedley, J. [Brookhaven National Laboratory, 20 Technology Street, Bldg. 535B, Brookhaven National Laboratory Upton, NY 11973 (United States); Wan, W. [Lawrence Berkeley National Laboratory, 1 Cyclotron Rd, Berkeley, CA 94720 (United States)

2010-10-21

This paper reviews the requirements and current status of cathodes for accelerator applications, and proposes a research and development plan for advancing cathode technology. Accelerator cathodes need to have long operational lifetimes and produce electron beams with a very low emittance. The two principal emission processes to be considered are thermionic and photoemission with the photocathodes being further subdivided into metal and semi-conductors. Field emission cathodes are not included in this analysis. The thermal emittance is derived and the formulas used to compare the various cathode materials. To date, there is no cathode which provides all the requirements needed for the proposed future light sources. Therefore a three part research plan is described to develop cathodes for these future light source applications.

Emission mechanism in high current hollow cathode arcs

International Nuclear Information System (INIS)

Krishnan, M.

1976-01-01

Large (2 cm-diameter) hollow cathodes have been operated in a magnetoplasmadynamic (MPD) arc over wide ranges of current (0.25 to 17 kA) and mass flow (10 -3 to 8 g/sec), with orifice current densities and mass fluxes encompassing those encountered in low current steady-state hollow cathode arcs. Detailed cathode interior measurements of current and potential distributions show that maximum current penetration into the cathode is about one diameter axially upstream from the tip, with peak inner surface current attachment up to one cathode diameter upstream of the tip. The spontaneous attachment of peak current upstream of the cathode tip is suggested as a criterion for characteristic hollow cathode operation. This empirical criterion is verified by experiment

Forensic Analysis of Blue Ball point Pen Inks Using Ultraviolet-Visible Spectrometer and Ultra-Performance Liquid Chromatograph

International Nuclear Information System (INIS)

Lee, L.C.; Shandu, K.T.S.; Nor Syahirah Mohamad Razi; Ab Aziz Ishak; Khairul Osman

2015-01-01

Twelve varieties of blue ball point pens were selected and analyzed using UV-Vis spectrometer and ultra-performance liquid chromatography (UPLC). The aim of the study was to determine discrimination power (DP) of these methods in differentiating pen inks collected from the market in Malaysia. Discrimination analysis of 66 possible pen-pair of blue ball point pens was carried out via one-way ANOVA based on obtained chromatogram and spectra. A total of 18 peaks were determined as coming from inks based on the chromatographic data extracted at three different wavelengths (279, 370 and 400 nm). While for the UV-Vis spectrometer analysis, presence of peaks at 303, 545, 577 and 584 nm wavelengths were recorded. UV-Vis spectral data were mainly produced by the colorant components (for example, dyes) found in inks and UPLC may detect ink components other than dyes, for example, additives. As conclusion, the DP for UV-Vis and UPLC were determined to be 72.12 % and 98.48 %, respectively. This manuscript demonstrates the potential of UPLC for discriminating pen inks based on non-dye components. Additionally, the dye components in inks do not seem to play important role in discrimination of pen inks. (author)

Growth of long triisopropylsilylethynyl pentacene (TIPS-PEN) nanofibrils in a polymer thin film during spin-coating.

Science.gov (United States)

Park, Minwoo; Min, Yuho; Lee, Yu-Jeong; Jeong, Unyong

2014-03-01

This study demonstrates the growth of long triisopropylsilyethynyl pentacene (TIPS-PEN) nanofibrils in a thin film of a crystalline polymer, poly(ε-caprolactone) (PCL). During spin-coating, TIPS-PEN molecules are locally extracted around the PCL grain boundaries and they crystallize into [010] direction forming long nanofibrils. Molecular weight of PCL and weight fraction (α) of TIPS-PEN in PCL matrix are key factors to the growth of nanofibrils. Long high-quality TIPS-PEN nanofibrils are obtained with high-molecular-weight PCL and at the α values in the range of 0.03-0.1. The long nanofibrils are used as an active layer in a field-effect organic transistor. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Mechanism of Corrosion of Activated Aluminum Particles by Hot Water

International Nuclear Information System (INIS)

Razavi-Tousi, S.S.; Szpunar, J.A.

2014-01-01

Mechanism of corrosion in aluminum particles by hot water treatment for hydrogen generation is evaluated. The aluminum powder was activated by ball milling for different durations, which modified size and microstructure of the particles. Open circuit potential test was carried out to elucidate different stages of the reaction. Tafel test was used to explain the effect of ball milling and growth of hydroxide layer on corrosion of the particles. Surface, cross section and thickness of the grown hydroxide on the aluminum particles were studied in a scanning electron microscope. The corrosion potential of the aluminum powders depends on microstructure of the aluminum particles, growth of the hydroxide layer and a change in pH because of cathodic reactions. The hydrogen production test showed that a deformed microstructure and smaller particle size accelerates the corrosion rate of aluminum by hot water, the effect of the deformed microstructure being more significant at the beginning of the reaction. Effect of growth of the hydroxide layer on corrosion mechanism is discussed

Beryllium electrodeposition on aluminium cathode from chloride melts

International Nuclear Information System (INIS)

Nichkov, I.F.; Novikov, E.A.; Serebryakov, G.A.; Kanashin, Yu.P.; Sardyko, G.N.

1980-01-01

Cathodic processes during beryllium deposition on liquid and solid aluminium cathodes are investigated. Mixture of sodium, potassium and beryllium chloride melts served as an lectrolyte. Beryllium ion discharge at the expense of alloy formation takes place at more positive potentials than on an indifferent cathode at low current densities ( in the case of liquid aluminium cathode). Metallographic analysis and measurements of microhardness have shown, that the cathodic product includes two phases: beryllium solid solution in aluminium and metallic beryllium. It is concluded, that aluminium-beryllium alloys with high cathodic yield by current can be obtained by the electrolytic method

Technical note: whole-pen assessments of nutrient excretion and digestibility from dairy replacement heifers housed in sand-bedded freestalls.

Science.gov (United States)

Coblentz, W K; Hoffman, P C; Esser, N M; Bertram, M G

2013-10-01

Our objectives were to describe and test refined procedures for quantifying excreta produced from whole pens of dairy heifers. Previous research efforts attempting to make whole-pen measurements of excreta output have been complicated by the use of organic bedding, which requires cumbersome analytical techniques to quantify excreta apart from the bedding. Research pens equipped with sand-bedded freestalls offer a unique opportunity for refinement of whole-pen fecal collection methods, primarily because sand-bedded freestall systems contain no organic bedding; therefore, concentrations of ash within the manure, sand, and feces can be used to correct for contamination of manure by sand bedding. This study was conducted on a subset of heifers from a larger production-scale feeding trial evaluating ensiled eastern gamagrass [Tripsacum dactyloides (L.) L.] haylage (EGG) that was incorporated into a corn silage/alfalfa haylage-based blended diet at rates of 0, 9.1, 18.3, or 27.4% of total DM. The diet without EGG also was offered on a limit-fed basis. Eighty Holstein dairy heifers were blocked (heavy weight, 424 ± 15.9 kg; light weight, 324 ± 22.4 kg) and then assigned to 10 individual pens containing 8 heifers/pen. One pen per block was assigned to each of the 5 research diets, and whole-pen fecal collections were conducted twice for each pen. Grab fecal samples also were gathered from individual heifers within each pen, and subsequent analysis of these whole-pen composites allowed reasonable estimates of OM and NDF excreta output. Under the conditions of our experimental design, pooled SEM for the excreta DM, OM, NDF, and NDF (ash corrected) output were 0.113, 0.085, 0.093, and 0.075 kg·heifer(-1)·d(-1), respectively. For DM excretion, this represented about one-third of the SEM reported for previous whole-pen collections from bedded-pack housing systems. Subsequent calculations of apparent DM and OM digestibilities indicated that the technique was sensitive, and

Emission ability of La-Sc-Mo cathode

International Nuclear Information System (INIS)

Yang Jiancan; Nie Zuoren; Xi Xiaoli; Wang Yiman

2004-01-01

In this paper La-Sc-Mo cathode has been prepared and its electron emission ability was measured. This type of cathode shows good electron emission performance that the saturated current density is 6.74 A cm -1 and the work function is about 2.59 eV at 1300 deg. C, which is much lower than thoriated tungsten cathode (Th-W). So it is a potential cathode to replace the Th-W cathode with radioactive pollution. Surface analysis shows that good emission ability due to the 20 nm surplus La layer and the element Sc may do good to the La diffusion to the surface

DARHT 2 kA Cathode Development

Energy Technology Data Exchange (ETDEWEB)

Henestroza, E.; Houck, T.; Kwan, J.W.; Leitner, M.; Miram, G.; Prichard, B.; Roy, P.K.; Waldron, W.; Westenskow, G.; Yu, S.; Bieniosek, F.M.

2009-03-09

In the campaign to achieve 2 kA of electron beam current, we have made several changes to the DARHT-II injector during 2006-2007. These changes resulted in a significant increase in the beam current, achieving the 2 kA milestone. Until recently (before 2007), the maximum beam current that was produced from the 6.5-inch diameter (612M) cathode was about 1300 A when the cathode was operating at a maximum temperature of 1140 C. At this temperature level, the heat loss was dominated by radiation which is proportional to temperature to the fourth power. The maximum operating temperature was limited by the damage threshold of the potted filament and the capacity of the filament heater power supply, as well as the shortening of the cathode life time. There were also signs of overheating at other components in the cathode assembly. Thus it was clear that our approach to increase beam current could not be simply trying to run at a higher temperature and the preferred way was to operate with a cathode that has a lower work function. The dispenser cathode initially used was the type 612M made by SpectraMat. According to the manufacturer's bulletin, this cathode should be able to produce more than 10 A/cm{sup 2} of current density (corresponding to 2 kA of total beam current) at our operating conditions. Instead the measured emission (space charge limited) was 6 A/cm{sup 2}. The result was similar even after we had revised the activation and handling procedures to adhere more closely to the recommend steps (taking longer time and nonstop to do the out-gassing). Vacuum was a major concern in considering the cathode's performance. Although the vacuum gauges at the injector vessel indicated 10{sup -8} Torr, the actual vacuum condition near the cathode in the central region of the vessel, where there might be significant out-gassing from the heater region, was never determined. Poor vacuum at the surface of the cathode degraded the emission (by raising the work function

DARHT 2 kA Cathode Development

International Nuclear Information System (INIS)

Henestroza, E.; Houck, T.; Kwan, J.W.; Leitner, M.; Miram, G.; Prichard, B.; Roy, P.K.; Waldron, W.; Westenskow, G.; Yu, S.; Bieniosek, F.M.

2009-01-01

In the campaign to achieve 2 kA of electron beam current, we have made several changes to the DARHT-II injector during 2006-2007. These changes resulted in a significant increase in the beam current, achieving the 2 kA milestone. Until recently (before 2007), the maximum beam current that was produced from the 6.5-inch diameter (612M) cathode was about 1300 A when the cathode was operating at a maximum temperature of 1140 C. At this temperature level, the heat loss was dominated by radiation which is proportional to temperature to the fourth power. The maximum operating temperature was limited by the damage threshold of the potted filament and the capacity of the filament heater power supply, as well as the shortening of the cathode life time. There were also signs of overheating at other components in the cathode assembly. Thus it was clear that our approach to increase beam current could not be simply trying to run at a higher temperature and the preferred way was to operate with a cathode that has a lower work function. The dispenser cathode initially used was the type 612M made by SpectraMat. According to the manufacturer's bulletin, this cathode should be able to produce more than 10 A/cm 2 of current density (corresponding to 2 kA of total beam current) at our operating conditions. Instead the measured emission (space charge limited) was 6 A/cm 2 . The result was similar even after we had revised the activation and handling procedures to adhere more closely to the recommend steps (taking longer time and nonstop to do the out-gassing). Vacuum was a major concern in considering the cathode's performance. Although the vacuum gauges at the injector vessel indicated 10 -8 Torr, the actual vacuum condition near the cathode in the central region of the vessel, where there might be significant out-gassing from the heater region, was never determined. Poor vacuum at the surface of the cathode degraded the emission (by raising the work function value). We reexamined

From Pen-and-Paper Sketches to Prototypes: The Advanced Interaction Design Environment

DEFF Research Database (Denmark)

Störrle, Harald

2014-01-01

Pen and paper is still the best tool for sketching GUIs. How-ever, sketches cannot be executed, at best we have facilitated or animated scenarios. The Advanced User Interaction Environment facilitates turn-ing hand-drawn sketches into executable prototypes.......Pen and paper is still the best tool for sketching GUIs. How-ever, sketches cannot be executed, at best we have facilitated or animated scenarios. The Advanced User Interaction Environment facilitates turn-ing hand-drawn sketches into executable prototypes....

Control of the conformations of ion Coulomb crystals in a Penning trap

Science.gov (United States)

Mavadia, Sandeep; Goodwin, Joseph F.; Stutter, Graham; Bharadia, Shailen; Crick, Daniel R.; Segal, Daniel M.; Thompson, Richard C.

2013-01-01

Laser-cooled atomic ions form ordered structures in radiofrequency ion traps and in Penning traps. Here we demonstrate in a Penning trap the creation and manipulation of a wide variety of ion Coulomb crystals formed from small numbers of ions. The configuration can be changed from a linear string, through intermediate geometries, to a planar structure. The transition from a linear string to a zigzag geometry is observed for the first time in a Penning trap. The conformations of the crystals are set by the applied trap potential and the laser parameters, and agree with simulations. These simulations indicate that the rotation frequency of a small crystal is mainly determined by the laser parameters, independent of the number of ions and the axial confinement strength. This system has potential applications for quantum simulation, quantum information processing and tests of fundamental physics models from quantum field theory to cosmology. PMID:24096901

Digital assist: A comparison of two note-taking methods (traditional vs. digital pen) for students with emotional behavioral disorders

Science.gov (United States)

Rody, Carlotta A.

High school biology classes traditionally follow a lecture format to disseminate content and new terminology. With the inclusive practices of No Child Left Behind, the Common Core State Standards, and end-of-course exam requirement for high school diplomas, classes include a large range of achievement levels and abilities. Teachers assume, often incorrectly, that students come to class prepared to listen and take notes. In a standard diploma, high school biology class in a separate school for students with emotional and behavioral disorders, five students participated in a single-subject, alternating treatment design study that compared the use of regular pens and digital pens to take notes during 21 lecture sessions. Behavior measures were threefold between the two interventions: (a) quantity of notes taken per minute during lectures, (b) quantity of notes or notations taken during review pauses, and (c) percent of correct responses on the daily comprehension quizzes. The study's data indicated that two students were inclined to take more lecture notes when using the digital pen. Two students took more notes with the regular pen. One student demonstrated no difference in her performance with either pen type. Both female students took more notes per minute, on average, than the three males regardless of pen type. During the review pause, three of the five students only added notes or notations to their notes when using the regular pen. The remaining two students did not add to their notes. Quiz scores differed in favor of the regular pen. All five participants earned higher scores on quizzes given during regular pen sessions. However, the differences were minor, and recommendations are made for specific training in note-taking, the pause strategy, and digital pen fluency which may produce different results for both note-taking and quiz scores.

Rechargeable lithium/polymer cathode batteries

Science.gov (United States)

Osaka, Tetsuya; Nakajima, Toshiki; Shiota, Koh; Owens, Boone B.

1989-06-01

Polypyrrole (PPy) and polyaniline (PAn) were investigated for cathode materials of rechargeable lithium batteries. PPy films prepared with PF6(-) anion and/or platinum substrate precoated with nitrile butadiene rubber (NBR) were excellent cathode materials because of rough and/or highly oriented film structure. PAn films were successfully prepared from non-aqueous propylene carbonate solution containing aniline, CF3COOH and lithium perchlorate. Its acidity strongly affects the anion doping-undoping behavior. The PAn cathode prepared in high acidic solution (e.g., 4:1 ratio of acid:aniline) gives the excellent battery performance.

Transport of three veterinary antimicrobials from feedlot pens via simulated rainfall runoff.

Science.gov (United States)

Sura, Srinivas; Degenhardt, Dani; Cessna, Allan J; Larney, Francis J; Olson, Andrew F; McAllister, Tim A

2015-07-15

Veterinary antimicrobials are introduced to wider environments by manure application to agricultural fields or through leaching or runoff from manure storage areas (feedlots, stockpiles, windrows, lagoons). Detected in manure, manure-treated soils, and surface and ground water near intensive cattle feeding operations, there is a concern that environmental contamination by these chemicals may promote the development of antimicrobial resistance in bacteria. Surface runoff and leaching appear to be major transport pathways by which veterinary antimicrobials eventually contaminate surface and ground water, respectively. A study was conducted to investigate the transport of three veterinary antimicrobials (chlortetracycline, sulfamethazine, tylosin), commonly used in beef cattle production, in simulated rainfall runoff from feedlot pens. Mean concentrations of veterinary antimicrobials were 1.4 to 3.5 times higher in surface material from bedding vs. non-bedding pen areas. Runoff rates and volumetric runoff coefficients were similar across all treatments but both were significantly higher from non-bedding (0.53Lmin(-1); 0.27) than bedding areas (0.40Lmin(-1); 0.19). In keeping with concentrations in pen surface material, mean concentrations of veterinary antimicrobials were 1.4 to 2.5 times higher in runoff generated from bedding vs. non-bedding pen areas. Water solubility and sorption coefficient of antimicrobials played a role in their transport in runoff. Estimated amounts of chlortetracycline, sulfamethazine, and tylosin that could potentially be transported to the feedlot catch basin during a one in 100-year precipitation event were 1.3 to 3.6ghead(-1), 1.9ghead(-1), and 0.2ghead(-1), respectively. This study demonstrates the magnitude of veterinary antimicrobial transport in feedlot pen runoff and supports the necessity of catch basins for runoff containment within feedlots. Crown Copyright © 2015. Published by Elsevier B.V. All rights reserved.

Pen confinement of yearling ewes with cows or heifers for 14 days to produce bonded sheep.

Science.gov (United States)

Fredrickson, E L.; Anderson, D M.; Estell, R E.; Havstad, K M.; Shupe, W L.; Remmenga, M D.

2001-06-01

Mixed species stocking is commonly a more ecologically sound and efficient use of forage resources than single species stocking, especially in pastures having complex assemblages of forage species. However, in many environments livestock predation on especially smaller ruminants adds an extra challenge to mixed species stocking. When mixed sheep and cattle remain consistently as a cohesive group (flerd), predation risks are lessened, while fencing and herding costs are reduced. To establish a cohesive group (bond), a 30-day bonding period in which young sheep and cattle pairs are penned together is currently recommended. The purpose of this research was to test if a bond could be produced in open field test. Other behaviors were also noted and recorded during the field test. Separation distance did not differ (P=0.973) between the PC and PH treatments; however, separation distance for NC versus NH (Ptime grazing and less time walking than animals not previously penned for 14 days. Penned animals also vocalized less than non-penned animals during the open field test. The bond sheep formed to the bovines was not affected by cow age. These data suggest that inter-specific bond formation using pen confinement can be accomplished within 14 days, representing a 53% savings in time and associated costs when compared to pen confinement lasting 30 days.

Insulin pen needles: effects of extra-thin wall needle technology on preference, confidence, and other patient ratings.

Science.gov (United States)

Aronson, Ronnie; Gibney, Michael A; Oza, Kunjal; Bérubé, Julie; Kassler-Taub, Kenneth; Hirsch, Laurence

2013-07-01

Pen needles (PNs) are essential for insulin injections using pen devices. PN characteristics affect patients' injection experience. The goal of this study was to evaluate the impact of a new extra-thin wall (XTW) PN versus usual PNs on overall patient preference, ease of injection, perceived time to complete the full dose, thumb button force to deliver the injection, and dose delivery confidence in individuals with diabetes mellitus (DM). Subjects injected insulin with the KwikPen(TM) (Eli Lilly and Company, Indianapolis, Indiana), SoloSTAR(®) (sanofi-aventis U.S. LLC, Bridgewater, New Jersey), and FlexPen(®) (Novo Nordisk A/S, Bagsvaerd, Denmark) insulin pens, and included some with impaired hand dexterity. We first performed quantitative testing of XTW and comparable PNs with the 3 insulin pens for thumb force, flow rate, and time to deliver medication. A prospective, randomized, 2-period, open-label, crossover trial was then conducted in patients aged 35 to 80 years with type 1 or type 2 DM who injected insulin by pen for ≥2 months, with at least 1 daily dose ≥10 U. Patients who used 4- to 8-mm length PNs with 31- to 32-G diameter were randomly assigned to use their current PN or the same/similar size XTW PN at home for ~1 week and the other PN the second week. They completed several comparative 150-mm visual analog scales and direct questions at the end of period 2. XTW PNs had statistically significant better performance for each studied PN characteristic (thumb force, flow, and time to deliver medication) for all pens combined and each individual pen brand (all, P ≤ 0.05). Of 216 patients randomized to study groups (80, SoloSTAR; 77, FlexPen; 59, KwikPen), 209 completed both periods; 198 were evaluable. Baseline characteristics revealed a mean (SD) age of 60.8 (9.3) years, insulin pen use duration of 4.3 (4.1) years, and mean total daily dose of 75.1 (52.3) U (range, 10-420 U). Approximately 50% of patients were female; 81.5% were white and 14.8% were

Space-charge effects in Penning ion traps

Czech Academy of Sciences Publication Activity Database

Porobic, T.; Beck, M.; Breitenfeldt, M.; Couratin, C.; Finlay, P.; Knecht, A.; Fabian, X.; Friedag, P.; Flechard, X.; Lienard, E.; Ban, G.; Zákoucký, Dalibor; Soti, G.; Van Gorp, S.; Weinheimer, C.; Wursten, E.; Severijns, N.

2015-01-01

Roč. 785, JUN (2015), s. 153-162 ISSN 0168-9002 R&D Projects: GA MŠk LA08015; GA MŠk(CZ) LG13031 Institutional support: RVO:61389005 Keywords : Penning trap * space-charge * magnetron motion * ion trapping * buffer gas cooling * ion cyclotron resonance Subject RIV: BG - Nuclear, Atomic and Molecular Physics, Colliders Impact factor: 1.200, year: 2015

Propylthiouracil Attenuates Experimental Pulmonary Hypertension via Suppression of Pen-2, a Key Component of Gamma-Secretase.

Directory of Open Access Journals (Sweden)

Ying-Ju Lai

Full Text Available Gamma-secretase-mediated Notch3 signaling is involved in smooth muscle cell (SMC hyper-activity and proliferation leading to pulmonary arterial hypertension (PAH. In addition, Propylthiouracil (PTU, beyond its anti-thyroid action, has suppressive effects on atherosclerosis and PAH. Here, we investigated the possible involvement of gamma-secretase-mediated Notch3 signaling in PTU-inhibited PAH. In rats with monocrotaline-induced PAH, PTU therapy improved pulmonary arterial hypertrophy and hemodynamics. In vitro, treatment of PASMCs from monocrotaline-treated rats with PTU inhibited their proliferation and migration. Immunocyto, histochemistry, and western blot showed that PTU treatment attenuated the activation of Notch3 signaling in PASMCs from monocrotaline-treated rats, which was mediated via inhibition of gamma-secretase expression especially its presenilin enhancer 2 (Pen-2 subunit. Furthermore, over-expression of Pen-2 in PASMCs from control rats increased the capacity of migration, whereas knockdown of Pen-2 with its respective siRNA in PASMCs from monocrotaline-treated rats had an opposite effect. Transfection of PASMCs from monocrotaline-treated rats with Pen-2 siRNA blocked the inhibitory effect of PTU on PASMC proliferation and migration, reflecting the crucial role of Pen-2 in PTU effect. We present a novel cell-signaling paradigm in which overexpression of Pen-2 is essential for experimental pulmonary arterial hypertension to promote motility and growth of smooth muscle cells. Propylthiouracil attenuates experimental PAH via suppression of the gamma-secretase-mediated Notch3 signaling especially its presenilin enhancer 2 (Pen-2 subunit. These findings provide a deep insight into the pathogenesis of PAH and a novel therapeutic strategy.

Electron beam generation form a superemissive cathode

International Nuclear Information System (INIS)

Hsu, T.-Y.; Liou, R.-L.; Kirkman-Amemiya, G.; Gundersen, M.A.

1991-01-01

An experimental study of electron beams produced by a superemissive cathode in the Back-Lighted Thyratron (BLT) and the pseudospark is presented. This work is motivated by experiments demonstrating very high current densities (≥10 kA/cm 2 over an area of 1 cm 2 ) from the pseudospark and BLT cathode. This high-density current is produced by field-enhanced thermionic emission from the ion beam-heated surface of a molybdenum cathode. This work reports the use of this cathode as a beam source, and is to be distinguished from previous work reporting hollow cathode-produced electron beams. An electron beam of more than 260 A Peak current has been produced with 15 kV applied voltage. An efficiency of ∼10% is estimated. These experimental results encourage further investigation of the super-emissive cathode as an intense electron beam source for applications including accelerator technology

Prevalence of digital dermatitis in young stock in Alberta, Canada, using pen walks.

Science.gov (United States)

Jacobs, C; Orsel, K; Barkema, H W

2017-11-01

Digital dermatitis (DD), an infectious bacterial foot lesion prevalent in dairy cattle worldwide, reduces both animal welfare and production. This disease was recently identified in replacement dairy heifers, with implications including increased risk of DD and decreased milk production in first lactation, poor reproductive performance, and altered hoof conformation. Therefore, a simple and effective method is needed to identify DD in young stock and to determine risk factors for DD in this group so that effective control strategies can be implemented. The objectives of this study were to (1) determine prevalence of DD in young stock (based on pen walks); and (2) identify potential risk factors for DD in young stock. A cross-sectional study was conducted on 28 dairy farms in Alberta, Canada; pen walks were used to identify DD (present/absent) on the hind feet of group-housed, young dairy stock. A subset of 583 young stock on 5 farms were selected for chute inspection of feet to determine the accuracy of pen walks for DD detection. Pen walks as a means of identifying DD lesions on the hind feet in young stock had sensitivity and specificity at the animal level of 65 and 98%, with positive and negative predictive values of 94 and 83%, respectively, at a prevalence of 37%. At the foot level, pen walks had sensitivity and specificity of 62 and 98%, respectively, with positive and negative predictive values of 92 and 88%, respectively, at a prevalence of 26%. Pen walks identified DD in 79 [2.9%; 95% confidence interval (95% CI): 2.3-3.6%] of 2,815 young stock on 11 (39%; 95% CI: 22-59%) of 28 farms, with all 79 DD-positive young stock ≥309 d of age. Apparent within-herd prevalence estimates ranged from 0 to 9.3%, with a mean of 1.4%. True within-herd prevalence of DD in young stock, calculated using the sensitivity and specificity of the pen walks, ranged from 0 to 12.6%, with a mean of 1.4%. On the 11 DD-positive farms, the proportion of young stock >12 mo of age

Cathodic electrogenerated chemiluminescence of aromatic Tb(III) chelates at polystyrene-graphite composite electrodes

International Nuclear Information System (INIS)

Salminen, Kalle; Grönroos, Päivi; Tuomi, Sami; Kulmala, Sakari

2017-01-01

Tb(III) chelates exhibit intense hot electron-induced electrogenerated chemiluminescence during cathodic polarization of metal/polystyrene-graphite (M/PG) electrodes in fully aqueous solutions. The M/PG working electrode provides a sensitive means for the determination of aromatic Tb(III) chelates at nanomolar concentration levels with a linear log-log calibration curve spanning more than five orders of magnitude. The charge transport and other properties of these novel electrodes were studied by electrochemiluminescence measurements and cyclic voltammetry. The present composite electrodes can by utilized both under pulse polarization and DC polarization unlike oxide-coated metal electrodes which do not tolerate cathodic DC polarization. The present cost-effective electrodes could be utilized e.g. in immunoassays where polystyrene is extensively used as a solid phase for various bioaffinity assays by using electrochemiluminescent Tb(III) chelates or e.g. Ru(bpy) 3 2+ as labels. - Highlights: • Generation of hydrated electrons at Polystyrene-graphite electrodes. • The insulating polystyrene layer on the outer electrode surface seems necessary. • Hydrated electrons are able to produce chemiluminescence. • Strongest signal and lowest std. dev. achieved at same graphite weight fraction.

Structural modifications of swift heavy ion irradiated PEN probed by optical and thermal measurements

International Nuclear Information System (INIS)

Devgan, Kusum; Singh, Lakhwant; Samra, Kawaljeet Singh

2013-01-01

Highlights: • The present paper reports the effect of swift heavy ion irradiation on Polyethylene Naphthalate (PEN). • Swift heavy ion irradiation introduces structural modification and degradation of PEN at different doses. • Lower irradiation doses in PEN result in modification of structural properties and higher doses lead to complete degradation. • Strong correlation between structural, optical, and thermal properties. - Abstract: The effects of swift heavy ion irradiation on the structural characteristics of Polyethylene naphthalate (PEN) were studied. Samples were irradiated in vacuum at room temperature by lithium (50 MeV), carbon (85 MeV), nickel (120 MeV) and silver (120 MeV) ions with the fluence in the range of 1×10 11 –3×10 12 ions cm −2 . Ion induced changes were analyzed using X-ray diffraction (XRD), Fourier transform infra red (FT-IR), UV–visible spectroscopy, thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC) techniques. Cross-linking was observed at lower doses resulting in modification of structural properties, however higher doses lead to the degradation of the investigated polymeric samples

Beam and hot spot formation in a low impedance driven vacuum spark

International Nuclear Information System (INIS)

Chuaqui, H.; Favre, M.; Soto, L.; Wyndham, E.

1990-01-01

Observations of a vacuum spark discharge plasma when driven by a 1.5 ω, 120 ns switched coaxial line at 60 kV open circuit voltage are made. A comparison of behaviour is made when a Nd: YAG laser over a range of energies is focussed either onto the anode or onto the cathode surface. A significantly different behaviour is seen if the line gap is shorted out allowing the sinusoidal voltage from the Marx to be applied to the electrodes. Hot spot formation with associated anode plasma are seen in this last case. (Author)

Electrodeposition of uranium in stirred liquid cadmium cathode

International Nuclear Information System (INIS)

Koyama, T.; Tanaka, H.

1997-01-01

The electrodeposition of U in a liquid Cd cathode was known to be hampered by the formation of dendritic U on the Cd surface. Electrotransports of uranium to the stirred liquid Cd cathode were carried out at 773 K for different cathode current densities and different Reynolds number of stirring. The maximum amount of U taken in the liquid Cd cathode without forming dendrites was found to increase with an increasing Reynolds number of stirring and decrease with increasing cathode current density. (orig.)

An EPR at Penly: an outline from the SFEN to feed the public debate

International Nuclear Information System (INIS)

Anon.

2010-01-01

Penly-3 is the project to build an EPR reactor as a third unit on the Penly site (France). The authors have reviewed 5 reasons to back it: 1) nuclear power is a useful source of energy at the world scale, 2) nuclear power is an adequate solution to meet our future needs of energy, 3) the EPR is at the top of today's nuclear technology, 4) nuclear power is an efficient tool to diminish CO 2 releases, and 5) The EPR is a valuable asset to maintain France in the top group of world actors in the nuclear sector. A public debate will be held soon concerning the Penly-3 project. (A.C.)

Reducing alarms and prioritising interventions in pig production by simultaneous monitoring of water consumption in multiple pens

DEFF Research Database (Denmark)

Dominiak, Katarina Nielsen; Hindsborg, Jeff; Pedersen, L. J.

to be generated at pen level or merged at section or herd level to reduce the number of alarms. Information on which specific pens or sections are of higher risk of stress or diseases is communicated to the farmer and target work effort to pens at risk. For Herd A, all model parameters defined at section level...... resulted in the best fit (MSE =13.85 litres2/hour). For Herd B, parameters defined at both pen and section level resulted in the best fit (MSE = 1.47 litres2/hour). For both Herd A and Herd B, preliminary results support the spatial approach by generating a reduced number of alarms when comparing section...

A one-dimensional model illustrating virtual-cathode formation in a novel coaxial virtual-cathode oscillator.

CSIR Research Space (South Africa)

Turner, GR

2014-09-01

Full Text Available A one-dimensional electrostatic sheet model of a coaxial geometry Virtual Cathode Oscillator (VCO) is presented. The cathode is centrally located and connects to a peripherally located plate electrode to form a resonant cavity, and is thus...

A Prototype of Mathematical Treatment of Pen Pressure Data for Signature Verification.

Science.gov (United States)

Li, Chi-Keung; Wong, Siu-Kay; Chim, Lai-Chu Joyce

2018-01-01

A prototype using simple mathematical treatment of the pen pressure data recorded by a digital pen movement recording device was derived. In this study, a total of 48 sets of signature and initial specimens were collected. Pearson's correlation coefficient was used to compare the data of the pen pressure patterns. From the 820 pair comparisons of the 48 sets of genuine signatures, a high degree of matching was found in which 95.4% (782 pairs) and 80% (656 pairs) had rPA > 0.7 and rPA > 0.8, respectively. In the comparison of the 23 forged signatures with their corresponding control signatures, 20 of them (89.2% of pairs) had rPA values prototype could be used as a complementary technique to improve the objectivity of signature examination and also has a good potential to be developed as a tool for automated signature identification. © 2017 American Academy of Forensic Sciences.

Explosive-emission cathode fabricated from superconducting cable

International Nuclear Information System (INIS)

Vavra, I.; Korenev, S.A.

1989-01-01

The authors describe on explosive-emission cathode that is based on stock superconducting cable - type NT-50, for example - that is bunched and held in a copper matrix. The copper matrix is partially etched away to create a multipoint structure for the cathode-plasma initiators. With 100-300 kV on the diode and a distance of 1 cm between the anode and cathode, electron currents of 20-80 and 60-300 A are obtained with cathode diameters of 0.5 and 1 cm, respectively

The influence of facility and home pen design on the welfare of the laboratory-housed dog.

Science.gov (United States)

Scullion Hall, Laura E M; Robinson, Sally; Finch, John; Buchanan-Smith, Hannah M

We have an ethical and scientific obligation to Refine all aspects of the life of the laboratory-housed dog. Across industry there are many differences amongst facilities, home pen design and husbandry, as well as differences in features of the dogs such as strain, sex and scientific protocols. Understanding how these influence welfare, and hence scientific output is therefore critical. A significant proportion of dogs' lives are spent in the home pen and as such, the design can have a considerable impact on welfare. Although best practice guidelines exist, there is a paucity of empirical evidence to support the recommended Refinements and uptake varies across industry. In this study, we examine the effect of modern and traditional home pen design, overall facility design, husbandry, history of regulated procedures, strain and sex on welfare-indicating behaviours and mechanical pressure threshold. Six groups of dogs from two facilities (total n=46) were observed in the home pen and tested for mechanical pressure threshold. Dogs which were housed in a purpose-built modern facility or in a modern design home pen showed the fewest behavioural indicators of negative welfare (such as alert or pacing behaviours) and more indicators of positive welfare (such as resting) compared to those in a traditional home pen design or traditional facility. Welfare indicating behaviours did not vary consistently with strain, but male dogs showed more negative welfare indicating behaviours and had greater variation in these behaviours than females. Our findings showed more positive welfare indicating behaviours in dogs with higher mechanical pressure thresholds. We conclude that factors relating to the design of home pens and implementation of Refinements at the facility level have a significant positive impact on the welfare of laboratory-housed dogs, with a potential concomitant impact on scientific endpoints. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights

Pen-on-paper strategy for point-of-care testing: Rapid prototyping of fully written microfluidic biosensor.

Science.gov (United States)

Li, Zedong; Li, Fei; Xing, Yue; Liu, Zhi; You, Minli; Li, Yingchun; Wen, Ting; Qu, Zhiguo; Ling Li, Xiao; Xu, Feng

2017-12-15

Paper-based microfluidic biosensors have recently attracted increasing attentions in point-of-care testing (POCT) territories benefiting from their affordable, accessible and eco-friendly features, where technologies for fabricating such biosensors are preferred to be equipment free, easy-to-operate and capable of rapid prototyping. In this work, we developed a pen-on-paper (PoP) strategy based on two custom-made pens, i.e., a wax pen and a conductive-ink pen, to fully write paper-based microfluidic biosensors through directly writing both microfluidic channels and electrodes. Particularly, the proposed wax pen is competent to realize one-step fabrication of wax channels on paper, as the melted wax penetrates into paper during writing process without any post-treatments. The practical applications of the fabricated paper-based microfluidic biosensors are demonstrated by both colorimetric detection of Salmonella typhimurium DNA with detection limit of 1nM and electrochemical measurement of glucose with detection limit of 1mM. The developed PoP strategy for making microfluidic biosensors on paper characterized by true simplicity, prominent portability and excellent capability for rapid prototyping shows promising prospect in POCT applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Hollow cathode for positive ion sources

International Nuclear Information System (INIS)

Schechter, D.E.; Kim, J.; Tsai, C.C.

1979-01-01

Development to incorporate hollow cathodes into high power ion sources for neutral beam injection systems is being pursued. Hollow tube LaB 6 -type cathodes, similar to a UCLA design, have been constructed and tested in several ORNL ion source configurations. Results of testing include arc discharge parameters of >1000 and 500 amps for 0.5 and 10 second pulse lengths, respectively. Details of cathode construction and additional performance results are discussed

Pen size and parity effects on maternal behaviour of Small-Tail Han sheep.

Science.gov (United States)

Lv, S-J; Yang, Y; Dwyer, C M; Li, F-K

2015-07-01

The aim of this experiment was to study the effects of pen size and parity on maternal behaviour of twin-bearing Small-Tail Han ewes. A total of 24 ewes were allocated to a 2×2 design (six per pen), with parity (primiparous or multiparous) and pen size (large: 6.0×3.0 m; small: 6.0×1.5 m) as main effects at Linyi University, Shandong Province, China. Behaviour was observed from after parturition until weaning. All ewes were observed for 6 h every 5 days from 0700 to1000 h and from 1400 to 1700 h. Continuous focal animal sampling was used to quantify the duration of maternal behaviours: sucking, grooming and following as well as the frequency of udder accepting, udder refusing and low-pitched bleating. Oestradiol and cortisol concentrations in the faeces (collected in the morning every 5 days) were detected using EIA kits. All lambs were weighed 24 h after parturition and again at weaning at 35 days of age. The small pen size significantly reduced following (Pbehaviour in sheep during lactation. The study is also the first to report on the maternal behaviour of Chinese native sheep breeds (Small-Tail Han sheep), with implications for the production of sheep in China.

Conversion of Squid Pens to Chitosanases and Proteases via Paenibacillus sp. TKU042

Directory of Open Access Journals (Sweden)

Chien Thang Doan

2018-03-01

Full Text Available Chitosanases and proteases have received much attention due to their wide range of applications. Four kinds of chitinous materials, squid pens, shrimp heads, demineralized shrimp shells and demineralized crab shells, were used as the sole carbon and nitrogen (C/N source to produce chitosanases, proteases and α-glucosidase inhibitors (αGI by four different strains of Paenibacillus. Chitosanase productivity was highest in the culture supernatants using squid pens as the sole C/N source. The maximum chitosanase activity of fermented squid pens (0.759 U/mL was compared to that of fermented shrimp heads (0.397 U/mL, demineralized shrimp shells (0.201 U/mL and demineralized crab shells (0.216 U/mL. A squid pen concentration of 0.5% was suitable for chitosanase, protease and αGI production via Paenibacillus sp. TKU042. Multi-purification, including ethanol precipitation and column chromatography of Macro-Prep High S as well as Macro-Prep DEAE (diethylaminoethyl, led to the isolation of Paenibacillus sp. TKU042 chitosanase and protease with molecular weights of 70 and 35 kDa, respectively. For comparison, 16 chitinolytic bacteria, including strains of Paenibacillus, were investigated for the production of chitinase, exochitinase, chitosanase, protease and αGI using two kinds of chitinous sources.

Explosive-emission cathode fabricated using track method

International Nuclear Information System (INIS)

Akap'ev, G.N.; Korenev, S.A.

1989-01-01

Fabrication technique for large area multipoint cathodes is described. The technique is based on channels filling with metal in the ion-irradiated dielectric film producted after channel etching. It is shown, that cathode may be used under explosive emission conditions. Characteristics of diode with the mentioned type cathodes are measured

Plasma Deposition of Oxide-Coated Cathodes

National Research Council Canada - National Science Library

Umstattd, Ryan

1998-01-01

...; such cathodes may also have applicability for lower current density continuous wave devices. This novel approach to manufacturing an oxide cathode eliminates the binders that may subsequently (and unpredictably...

Cathode plasma expansion in diode with explosive emission

International Nuclear Information System (INIS)

Zuo Yinghong; Fan Ruyu; Wang Jianguo; Zhu Jinhui

2012-01-01

The evolution characteristics of the cathode plasma in a planar diode with explosive emission were analyzed. Be- sides the axial expansion which can reduce the effective anode-cathode gap, the radial expansion of the cathode plasma which can affect the effective emitting area was also taken into account. According to the Child-Langmuir law and the experimental data of current and voltage with a electron vacuum diode under four-pulse mode, the dynamics of the cathode plasma was investigated, on the assumption that the radial speeds of the cathode plasma was approximately equal to the axial speed. The results show that the radial and axial expansion speeds of the cathode plasma are 0.9-2.8 cm/μs. (authors)

A multivariate dynamic linear model for early warnings of diarrhea and pen fouling in slaughter pigs

DEFF Research Database (Denmark)

Jensen, Dan Børge; Toft, Nils; Kristensen, Anders Ringgaard

2017-01-01

We present a method for providing early, but indiscriminant, predictions of diarrhea and pen fouling in grower/finisher pigs. We collected data on dispensed feed amount, water flow, drinking bouts frequency, temperature at two positions per pen, and section level humidity from 12 pens (6 double...... a set threshold a sufficient number of times, consecutively. Using this method with a 7 day prediction window, we achieved an area under the receiver operating characteristics curve of 0.84. Shorter prediction windows yielded lower performances, but longer prediction windows did not affect...

The recovery of zinc from hot galvanizing slag in an anion-exchange membrane electrolysis reactor

International Nuclear Information System (INIS)

Ren Xiulian; Wei Qifeng; Hu Surong; Wei Sijie

2010-01-01

This paper reports the optimization of the process parameters for recovery of zinc from hot galvanizing slag in an anion-exchange membrane electrolysis reactor. The experiments were carried out in an ammoniacal ammonium chloride system. The influence of composition of electrolytes, pH, stirring rate, current density and temperature, on cathodic current efficiency, specific power consumption and anodic dissolution of Zn were investigated. The results indicate that the cathode current efficiency increases and the hydrogen evolution decreased with increasing the cathode current density. The partial current for electrodeposition of Zn has liner relationship with ω 1/2 (ω: rotation rate). The highest current efficiency for dissolving zinc was obtained when NH 4 Cl concentration was 53.46 g L -1 and the anodic dissolution of zinc was determined by mass transfer rate at stirring rate 0-300 r min -1 . Increase in temperature benefits to improve CE and dissolution of Zn, and reduce cell voltage. Initial pH of electrolytes plays an important role in the deposition and anodic dissolution of Zn. The results of single factor experiment show that about 50% energy consumption was saved for electrodeposition of Zn in the anion-exchange membrane electrolysis reactor.

Cathodic corrosion: Part 2. Properties of nanoparticles synthesized by cathodic corrosion

International Nuclear Information System (INIS)

Yanson, A.I.; Yanson, Yu.I.

2013-01-01

We demonstrate how cathodic corrosion in concentrated aqueous solutions enables one to prepare nanoparticles of various metals and metal alloys. Using various characterization methods we show that the composition of nanoparticles remains that of the starting material, and the resulting size distribution remains rather narrow. For the case of platinum we show how the size and possibly even the shape of the nanoparticles can be easily controlled by the parameters of corrosion. Finally, we discuss the advantages of using the nanoparticles prepared by cathodic corrosion for applications in (electro-)catalysis.

Pen Branch Delta and Savannah River Swamp Hydraulic Model

International Nuclear Information System (INIS)

Chen, K.F.

1999-01-01

The proposed Savannah River Site (SRS) Wetlands Restoration Project area is located in Barnwell County, South Carolina on the southwestern boundary of the SRS Reservation. The swamp covers about 40.5 km2 and is bounded to the west and south by the Savannah River and to the north and east by low bluffs at the edge of the Savannah River floodplain. Water levels within the swamp are determined by stage along the Savannah River, local drainage, groundwater seepage, and inflows from four tributaries, Beaver Dam Creek, Fourmile Branch, Pen Branch, and Steel Creek. Historic discharges of heated process water into these tributaries scoured the streambed, created deltas in the adjacent wetland, and killed native vegetation in the vicinity of the delta deposits. Future releases from these tributaries will be substantially smaller and closer to ambient temperatures. One component of the proposed restoration project will be to reestablish indigenous wetland vegetation on the Pen Branch delta that covers about 1.0 km2. Long-term predictions of water levels within the swamp are required to determine the characteristics of suitable plants. The objective of the study was to predict water levels at various locations within the proposed SRS Wetlands Restoration Project area for a range of Savannah River flows and regulated releases from Pen Branch. TABS-MD, a United States Army Corps of Engineer developed two-dimensional finite element open channel hydraulic computer code, was used to model the SRS swamp area for various flow conditions

Cathodic disbonding of organic coatings on submerged steel

Energy Technology Data Exchange (ETDEWEB)

Knudsen, Ole oeystein

1998-12-31

In offshore oil production, submerged steel structures are commonly protected by an organic coating in combination with cathodic protection. The main advantage is that the coating decreases the current demand for cathodic protection. But the coating degrades with time. This thesis studies one of the most important mechanisms for coating degradation in seawater, cathodic disbonding. Seven commercial coatings and two model coatings with various pigmentations have been studied. Parameter studies, microscopy and studies of free films were used in the mechanism investigations. Exposure to simulated North Sea conditions was used in the performance studies. The effect of aluminium and glass barrier pigments on cathodic disbonding was investigated. The mechanism for the effect of the aluminium pigments on cathodic disbonding was also investigated. The transport of charge and oxygen to the steel/coating interface during cathodic disbonding was studied for two epoxy coatings. Cathodic disbonding, blistering and current demand for cathodic protection was measured for nine commercial coatings for submerged steel structures, using the ASTM-G8 standard test and a long term test under simulated North Sea conditions. The relevance of the ASTM-G8 test as a prequalification test was evaluated. 171 refs., 40 figs., 6 tabs.

Students’ Attention when Using Touchscreens and Pen Tablets in a Mathematics Classroom

Directory of Open Access Journals (Sweden)

Chiung-Hui Chiu

2017-03-01

Full Text Available Aim/Purpose: The present study investigated and compared students’ attention in terms of time-on-task and number of distractors between using a touchscreen and a pen tablet in mathematical problem-solving activities with virtual manipulatives. Background: Although there is an increasing use of these input devices in educational practice, little research has focused on assessing student attention while using touchscreens or pen tablets in a mathematics classroom. Methodology: A qualitative exploration was conducted in a public elementary school in New Taipei, Taiwan. Six fifth-grade students participated in the activities. Video recordings of the activities and the students’ actions were analyzed. Findings: The results showed that students in the activity using touchscreens maintained greater attention and, thus, had more time-on-task and fewer distractors than those in the activity using pen tablets. Recommendations for Practitioners: School teachers could employ touchscreens in mathematics classrooms to support activities that focus on students’ manipulations in relation to the attention paid to the learning content. Recommendation for Researchers: The findings enhance our understanding of the input devices used in educational practice and provide a basis for further research. Impact on Society: The findings may also shed light on the human-technology interaction process involved in using pen and touch technology conditions. Future Research: Activities similar to those reported here should be conducted using more participants. In addition, it is important to understand how students with different levels of mathematics achievement use the devices in the activities.

Development and Evaluation of an Interactive Pen

Directory of Open Access Journals (Sweden)

Froilan G. Destreza

2015-11-01

Full Text Available Technologies have reached the classroom. It is one of the means of teaching strategies nowadays. Multimedia projectors have become one of the teaching tools the teacher cannot bear without it. The concept of making this tool to be interactive and easier to use was far conceived by the researcher. The researcher’s objective was to develop such tool and evaluate it according to its portability, simplicity, robustness, user-friendliness, effectiveness and efficiency. The respondents of the project were both the students and teachers of Batangas State University ARASOF-Nasugbu. The researcher has developed different prototypes for the interactive pen and tested in different environment and demonstrated the “know-how” of the project. The project was built using a simple infrared light emitting diode (IR LED, infrared tracker, and software which computes, detects and interact with the application program. Evaluation of the project followed the demonstration. The project got a high acceptance according to its portability, simplicity, robustness, user-friendliness, effectiveness and efficiency. The researcher is recommending the full implementation of the project in the Batangas State University ARASOF- Nasugbu and for better enhancement of the project by eliminating the pen.

Pen Culture of the Black-Chinned Tilapia, Sarotherodon ...

African Journals Online (AJOL)

Pen-fish-culture as a culture-based fisheries approach was investigated in the Aglor Lagoon from December 2003 to June, 2004. The fish used in the study was the Black-chinned tilapia Sarotherodon melanotheron. The growth performance of S. melanotheron cultured for six months in the Aglor Lagoon under three ...

Design Of Photovoltaic Powered Cathodic Protection System

Directory of Open Access Journals (Sweden)

Golina Samir Adly

2017-07-01

Full Text Available The corrosion caused by chemical reaction between metallic structures and surrounding mediums such as soil or water .the CP cathodic protection system is used to protect metallic structure against corrosion. Cathodic protection CP used to minimize corrosion by utilizing an external source of electrical current which forces the entire structure to become a cathode. There are two Types of cathodic protection system Galvanic current Impressed current.the Galvanic current is called a sacrificial anode is connected to the protected structure cathode through a DC power supply. In Galvanic current system a current passes from the sacrificing anode to the protected structure .the sacrificial anode is corroded rather than causing the protected structure corrosion .protected structure requires a constant current to stop the corrosion which determined by area structure metal and the surrounding medium. The rains humidity are decrease soil resistivity and increase the DC current .The corrosion and over protection resulting from increase in the DC current is harmful for the metallic structure. This problem can be solved by conventional cathodic protection system by manual adjustment of DC voltage periodically to obtain a constant current .the manual adjustment of DC voltage depends on experience of the technician and using the accuracy of the measuring equipment. The errors of measuring current depend on error from the technician or error from the measuring equipment. the corrosion of structure may occur when the interval between two successive adjustment is long .An automatically regulated cathodic protection system is used to overcome problems from conventional cathodic protection system .the regulated cathodic protection system adjust the DC voltage of the system automatically when it senses the variations of surrounding medium resistivity so the DC current is constant at the required level.

Cold cathodes on ultra-dispersed diamond base

International Nuclear Information System (INIS)

Alimova, A.N.; Zhirnov, V.V.; Chubun, N.N.; Belobrov, P.I.

1998-01-01

Prospects of application of nano diamond powders for fabrication of cold cathodes are discussed.Cold cathodes based on silicon pointed structures with nano diamond coatings were prepared.The deposition technique of diamond coating was dielectrophoresis from suspension of nano diamond powder in organic liquids.The cathodes were tested in sealed prototypes of vacuum electronic devices

Preliminary results on the chemical characterisation of the cathode nickel--emissive layer interface in oxide cathodes

International Nuclear Information System (INIS)

Jenkins, S.N.; Barber, D.K.; Whiting, M.J.; Baker, M.A.

2003-01-01

In cathode ray tube (CRT) thermionic oxide cathodes, the nickel-oxide interface properties are key to understanding the mechanisms of operation. At the elevated operational temperatures, free barium is formed at the interface by the reaction of reducing activators, from the nickel alloy, with barium oxide. The free barium diffuses to the outer surface of the oxide providing a low work function electron-emitting surface. However, during cathode life an interface layer grows between the nickel alloy and oxide, comprised of reaction products. The interfacial layer sets limits on the cathode performance and useful operational lifetime by inhibiting the barium reducing reaction. This paper discusses sample preparation procedures for exposure of the interface and the use of several surface and bulk analytical techniques to study interface layer formation. SEM, AES and SIMS data are presented, which provide preliminary insight into the mechanisms operating during the cathode's lifetime. There is evidence that the activator elements in the nickel alloy base, Al and Mg, are able to diffuse to the surface of the oxide during activation and ageing and that these elements are enriched at the interface after accelerated life

Studies on pulsed optogalvanic effect in Eu/Ne hollow cathode discharge.

Science.gov (United States)

Saini, V K; Kumar, P; Dixit, S K; Nakhe, S V

2014-07-01

The optogalvanic (OG) effect has been observed in a Eu/Ne hollow cathode discharge lamp using pulsed laser irradiation. An OG spectrum is recorded in dye laser wavelength region 574–602 nm using a boxcar-averager. In total 41 atomic lines are observed. Of these, 38 lines are assigned to neon transitions. Two lines observed corresponding to wavelengths 576.519 and 601.815 nm are assigned to europium transitions; (4f 7 6s 2 , S 8 7/2 →4f 7 6s6p , zP 6 7/2 ) and (4f 7 6s 2 , S 8 7/2 →4f 7 6s6p , zP 8 9/2 ), respectively, and the remaining line at 582.475 nm could not be assigned. The effect of the discharge current on europium as well as neon OG signals is also studied. At moderate discharge current values, an extra positive peak is observed in neon OG signal for the transition (1s 5 →2p 2 ) at 588.189 nm, which is explained by Penning-ionization process using the quasi-resonant energy transfer interactions between excited neon and europium atoms lying in 2p 2 and D 10 9/2 states, respectively.

AB/sub 5/-catalyzed hydrogen evolution cathodes

Energy Technology Data Exchange (ETDEWEB)

Hall, D E; Sawada, T; Shepard, V R; Tsujikawa, Y

1984-01-01

The AB/sub 5/ metal compounds are highly efficient hydrogen evolution electrocatalysts in alkaline electrolyte. Three types of AB/sub 5/-catalyzed cathode structures were made, using the hydride-forming AB/sub 5/ compounds in particulate form. Plastic-bonded cathodes containing >90 w/o AB/sub 5/ (finished-weight basis) were the most efficient, giving hydrogen evolution overpotentials (/eta/ /SUB H2/ ) of about 0.05 V at 200 mA cm/sup -2/. However, they tended to swell and shed material during electrolysis. Pressed, sintered cathodes containing 40-70 w/o catalyst in a nickel binder gave /eta/ /SUB H2/ about0.08 V; catalyst retention was excellent. Porous, sintered cathode coatings were made with 30-70 w/o AB/sub 5/ catalyst loadings. Their overpotentials were similar to those of the pressed, sintered cathodes. However, at catalyst loadings below about 40 w/o, high overpotentials characteristic of the nickel binder were observed. The structural and electrochemical properties of the three AB/sub 5/-catalyzed cathodes are discussed.

Filtered cathodic arc source

International Nuclear Information System (INIS)

Falabella, S.; Sanders, D.M.

1994-01-01

A continuous, cathodic arc ion source coupled to a macro-particle filter capable of separation or elimination of macro-particles from the ion flux produced by cathodic arc discharge is described. The ion source employs an axial magnetic field on a cathode (target) having tapered sides to confine the arc, thereby providing high target material utilization. A bent magnetic field is used to guide the metal ions from the target to the part to be coated. The macro-particle filter consists of two straight solenoids, end to end, but placed at 45 degree to one another, which prevents line-of-sight from the arc spot on the target to the parts to be coated, yet provides a path for ions and electrons to flow, and includes a series of baffles for trapping the macro-particles. 3 figures

A feature based comparison of pen and swipe based signature characteristics.

Science.gov (United States)

Robertson, Joshua; Guest, Richard

2015-10-01

Dynamic Signature Verification (DSV) is a biometric modality that identifies anatomical and behavioral characteristics when an individual signs their name. Conventionally signature data has been captured using pen/tablet apparatus. However, the use of other devices such as the touch-screen tablets has expanded in recent years affording the possibility of assessing biometric interaction on this new technology. To explore the potential of employing DSV techniques when a user signs or swipes with their finger, we report a study to correlate pen and finger generated features. Investigating the stability and correlation between a set of characteristic features recorded in participant's signatures and touch-based swipe gestures, a statistical analysis was conducted to assess consistency between capture scenarios. The results indicate that there is a range of static and dynamic features such as the rate of jerk, size, duration and the distance the pen traveled that can lead to interoperability between these two systems for input methods for use within a potential biometric context. It can be concluded that this data indicates that a general principle is that the same underlying constructional mechanisms are evident. Copyright © 2015 Elsevier B.V. All rights reserved.

Understanding the Role of Temperature and Cathode Composition on Interface and Bulk: Optimizing Aluminum Oxide Coatings for Li-Ion Cathodes

International Nuclear Information System (INIS)

Han, Binghong; Paulauskas, Tadas; Key, Baris; Peebles, Cameron; Park, Joong Sun

2017-01-01

Here, surface coating of cathode materials with Al_2O_3 has been shown to be a promising method for cathode stabilization and improved cycling performance at high operating voltages. However, a detailed understanding on how coating process and cathode composition changes the chemical composition, morphology and distribution of coating within cathode interface and bulk lattice, is still missing. In this study, we use a wet-chemical method to synthesize a series of Al_2O_3-coated LiNi_0_._5Co_0_._2Mn_0_._3O_2 and LiCoO_2 cathodes treated under various annealing temperatures and a combination of structural characterization techniques to understand the composition, homogeneity and morphology of coating layer and the bulk cathode. Nuclear magnetic resonance and electron microscopy results reveal that the nature of the interface is highly depended on the annealing temperature and cathode composition. For Al_2O_3-coated LiNi_0_._5Co_0_._2Mn_0_._3O_2, higher annealing temperature leads to more homogeneous and more closely attached coating on cathode materials, corresponding to better electrochemical performance. Lower Al_2O_3 coating content is found to be helpful to further improve the initial capacity and cyclability, which can greatly outperform the pristine cathode material. For Al_2O_3-coated LiCoO_2, the incorporation of Al into the cathode lattice is observed after annealing at high temperatures, implying the transformation from “surface coatings” to “dopants”, which is not observed for LiNi_0_._5Co_0_._2Mn_0_._3O_2. As a result, Al_2O_3-coated LiCoO_2 annealed at higher temperature shows similar initial capacity but lower retention compared to that annealed at a lower temperature, due to the intercalation of surface alumina into the bulk layered structure forming a solid solution.

Understanding the Role of Temperature and Cathode Composition on Interface and Bulk: Optimizing Aluminum Oxide Coatings for Li-Ion Cathodes.

Science.gov (United States)

Han, Binghong; Paulauskas, Tadas; Key, Baris; Peebles, Cameron; Park, Joong Sun; Klie, Robert F; Vaughey, John T; Dogan, Fulya

2017-05-03

Surface coating of cathode materials with Al 2 O 3 has been shown to be a promising method for cathode stabilization and improved cycling performance at high operating voltages. However, a detailed understanding on how coating process and cathode composition change the chemical composition, morphology, and distribution of coating within the cathode interface and bulk lattice is still missing. In this study, we use a wet-chemical method to synthesize a series of Al 2 O 3 -coated LiNi 0.5 Co 0.2 Mn 0.3 O 2 and LiCoO 2 cathodes treated under various annealing temperatures and a combination of structural characterization techniques to understand the composition, homogeneity, and morphology of the coating layer and the bulk cathode. Nuclear magnetic resonance and electron microscopy results reveal that the nature of the interface is highly dependent on the annealing temperature and cathode composition. For Al 2 O 3 -coated LiNi 0.5 Co 0.2 Mn 0.3 O 2 , higher annealing temperature leads to more homogeneous and more closely attached coating on cathode materials, corresponding to better electrochemical performance. Lower Al 2 O 3 coating content is found to be helpful to further improve the initial capacity and cyclability, which can greatly outperform the pristine cathode material. For Al 2 O 3 -coated LiCoO 2 , the incorporation of Al into the cathode lattice is observed after annealing at high temperatures, implying the transformation from "surface coatings" to "dopants", which is not observed for LiNi 0.5 Co 0.2 Mn 0.3 O 2 . As a result, Al 2 O 3 -coated LiCoO 2 annealed at higher temperature shows similar initial capacity but lower retention compared to that annealed at a lower temperature, due to the intercalation of surface alumina into the bulk layered structure forming a solid solution.

Pen-mate directed behaviour in ad libitum fed pigs given different quantities and frequencies of straw

DEFF Research Database (Denmark)

Williams, Charlotte Amdi; Lahrmann, H. P.; Oxholm, L. C.

2015-01-01

Straw stimulates explorative behaviour and is therefore attractive to pigs. Further, it can be effective in reducing negative pen-mate directed behaviours. Under most commercial conditions, straw can only be used in limited amounts as it can be difficult to handle in most vacuum slurry systems...... as a control treatment, against which the other treatments (quantities T25 and T50) and frequencies of straw allocations (T2×50 and T4×25) were tested. Three focal pigs per pen were randomly chosen and observed for 15 min per hour where tail-in-mouth, ear-in-mouth, aggression and other pen-mate directed...... behaviour were recorded. In addition, residual straw in the pens was assessed using four categories ranging from straw in a thin layer; little straw; few straws; and soiled straw. Pigs were active for about 30% of the registered time, but overall no differences in total pen-mate directed behaviour (tail...

(D-Pen2,4 prime -125I-Phe4,D-Pen5)enkephalin: A selective high affinity radioligand for delta opioid receptors with exceptional specific activity

Energy Technology Data Exchange (ETDEWEB)

Knapp, R.J.; Sharma, S.D.; Toth, G.; Duong, M.T.; Fang, L.; Bogert, C.L.; Weber, S.J.; Hunt, M.; Davis, T.P.; Wamsley, J.K. (Department of Pharmacology, University of Arizona, College of Medicine, Tucson (United States))

1991-09-01

(D-Pen2,4{prime}-125I-Phe4,D-Pen5)enkephalin ((125I)DPDPE) is a highly selective radioligand for the delta opioid receptor with a specific activity (2200 Ci/mmol) that is over 50-fold greater than that of tritium-labeled DPDPE analogs. (125I)DPDPE binds to a single site in rat brain membranes with an equilibrium dissociation constant (Kd) value of 421 {plus minus} 67 pM and a receptor density (Bmax) value of 36.4 {plus minus} 2.7 fmol/mg protein. The high affinity of this site for delta opioid receptor ligands and its low affinity for mu or kappa receptor-selective ligands are consistent with its being a delta opioid receptor. The distribution of these sites in rat brain, observed by receptor autoradiography, is also consistent with that of delta opioid receptors. Association and dissociation binding kinetics of 1.0 nM (125I) DPDPE are monophasic at 25 degrees C. The association rate (k + 1 = 5.80 {plus minus} 0.88 {times} 10(7) M-1 min-1) is about 20- and 7-fold greater than that measured for 1.0 nM (3H) DPDPE and 0.8 nM (3H) (D-Pen2,4{prime}-Cl-Phe4, D-Pen5)enkephalin, respectively. The dissociation rate of (125I)DPDPE (0.917 {plus minus} 0.117 {times} 10(-2) min-1) measured at 1.0 nM is about 3-fold faster than is observed for either of the other DPDPE analogs. The rapid binding kinetics of (125I)DPDPE is advantageous because binding equilibrium is achieved with much shorter incubation times than are required for other cyclic enkephalin analogs. This, in addition to its much higher specific activity, makes (125I)DPDPE a valuable new radioligand for studies of delta opioid receptors.

Feedlot- and Pen-Level Prevalence of Enterohemorrhagic Escherichia coli in Feces of Commercial Feedlot Cattle in Two Major U.S. Cattle Feeding Areas.

Science.gov (United States)

Cull, Charley A; Renter, David G; Dewsbury, Diana M; Noll, Lance W; Shridhar, Pragathi B; Ives, Samuel E; Nagaraja, Tiruvoor G; Cernicchiaro, Natalia

2017-06-01

The objective of this study was to determine feedlot- and pen-level fecal prevalence of seven enterohemorrhagic Escherichia coli (EHEC) belonging to serogroups (O26, O45, O103, O111, O121, O145, and O157, or EHEC-7) in feces of feedlot cattle in two feeding areas in the United States. Cattle pens from four commercial feedlots in each of the two major U.S. beef cattle areas were sampled. Up to 16 pen-floor fecal samples were collected from each of 4-6 pens per feedlot, monthly, for a total of three visits per feedlot, from June to August, 2014. Culture procedures including fecal enrichment in E. coli broth, immunomagnetic separation, and plating on selective media, followed by confirmation through polymerase chain reaction (PCR) testing, were conducted. Generalized linear mixed models were fitted to estimate feedlot-, pen-, and sample-level fecal prevalence of EHEC-7 and to evaluate associations between potential demographic and management risk factors with feedlot and within-pen prevalence of EHEC-7. All study feedlots and 31.0% of the study pens had at least one non-O157 EHEC-positive fecal sample, whereas 62.4% of pens tested positive for EHEC O157; sample-level prevalence estimates ranged from 0.0% for EHEC O121 to 18.7% for EHEC O157. Within-pen prevalence of EHEC O157 varied significantly by sampling month; similarly within-pen prevalence of non-O157 EHEC varied significantly by month and by the sex composition of the pen (heifer, steer, or mixed). Feedlot management factors, however, were not significantly associated with fecal prevalence of EHEC-7. Intraclass correlation coefficients for EHEC-7 models indicated that most of the variation occurred between pens, rather than within pens, or between feedlots. Hence, the potential combination of preharvest interventions and pen-level management strategies may have positive food safety impacts downstream along the beef chain.

Poli(Etileno Naftalato - PEN: uma revisão do seu histórico e as principais tendências de sua aplicação mundial Poly(ethylene naphtalate - PEN: historical review and main trends in world application

Directory of Open Access Journals (Sweden)

Edilene de Cássia D. Nunes

1998-06-01

Full Text Available Este artigo contém uma revisão sobre o Poli(etileno naftalato - PEN e também inclui vários aspectos relacionados com as blendas poliméricas Poli(etileno tereftalato - PET / Poli(etileno naftalato - PEN. O artigo é resultado de um desenvolvimento conjunto da Alcoa Alumínio S.A.- Divisão de Embalagens e do Departamento de Engenharia de Materiais - Universidade Federal de São Carlos (UFSCar, que tem como objetivo pesquisar o tema aqui abordado.This paper presents a review on poly(ethylene naphtalate - PEN including several features related to poly(ethylene terephtalate - PET / poly(ethylene naphtalate - PEN blends.The paper is a result of a conjoint development of Alcoa S.A. - Packaging Divisions and of the Department of Materials Engineering - Federal University of São Carlos (UFSCar, whose scope is to investigate the subject here approached.

Le Pen õigustas natside tegevust Prantsusmaal / Margo Pajuste

Index Scriptorium Estoniae

Pajuste, Margo

2005-01-01

Prantsuse paremäärmusliku partei juht Jean-Marie Le Pen väitis, et Saksa okupatsioon II maailmasõja ajal Prantsusmaal ei olnud eriti ebainimlik ja et kui väited massimõrvade kohta Prantsusmaal vastaksid tõele, poleks olnud vaja luua koonduslaagreid poliitvangidele. Reageeringutest Le Peni väidete kohta Prantsusmaal

Cost minimization analysis of different growth hormone pen devices based on time-and-motion simulations

Directory of Open Access Journals (Sweden)

Kim Jaewhan

2010-04-01

Full Text Available Abstract Background Numerous pen devices are available to administer recombinant Human Growth Hormone (rhGH, and both patients and health plans have varying issues to consider when selecting a particular product and device for daily use. Therefore, the present study utilized multi-dimensional product analysis to assess potential time involvement, required weekly administration steps, and utilization costs relative to daily rhGH administration. Methods Study objectives were to conduct 1 Time-and-Motion (TM simulations in a randomized block design that allowed time and steps comparisons related to rhGH preparation, administration and storage, and 2 a Cost Minimization Analysis (CMA relative to opportunity and supply costs. Nurses naïve to rhGH administration and devices were recruited to evaluate four rhGH pen devices (2 in liquid form, 2 requiring reconstitution via TM simulations. Five videotaped and timed trials for each product were evaluated based on: 1 Learning (initial use instructions, 2 Preparation (arrange device for use, 3 Administration (actual simulation manikin injection, and 4 Storage (maintain product viability between doses, in addition to assessment of steps required for weekly use. The CMA applied micro-costing techniques related to opportunity costs for caregivers (categorized as wages, non-drug medical supplies, and drug product costs. Results Norditropin® NordiFlex and Norditropin® NordiPen (NNF and NNP, Novo Nordisk, Inc., Bagsværd, Denmark took less weekly Total Time (p ® Pen (GTP, Pfizer, Inc, New York, New York or HumatroPen® (HTP, Eli Lilly and Company, Indianapolis, Indiana. Time savings were directly related to differences in new package Preparation times (NNF (1.35 minutes, NNP (2.48 minutes GTP (4.11 minutes, HTP (8.64 minutes, p Conclusions Time-and-motion simulation data used to support a micro-cost analysis demonstrated that the pen device with the greater time demand has highest net costs.

Li- and Mn-Rich Cathode Materials: Challenges to Commercialization

Energy Technology Data Exchange (ETDEWEB)

Zheng, Jianming [Energy and Environmental Directorate, Pacific Northwest National Laboratory, 902 Battelle Boulevard Richland WA 99354 USA; Myeong, Seungjun [School of Energy and Chemical Engineering, Green Energy Materials Development Center, Ulsan National Institute of Science and Technology (UNIST), Korea 689-798; Cho, Woongrae [School of Energy and Chemical Engineering, Green Energy Materials Development Center, Ulsan National Institute of Science and Technology (UNIST), Korea 689-798; Yan, Pengfei [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, 902 Battelle Boulevard Richland WA 99354 USA; Xiao, Jie [Energy and Environmental Directorate, Pacific Northwest National Laboratory, 902 Battelle Boulevard Richland WA 99354 USA; Wang, Chongmin [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, 902 Battelle Boulevard Richland WA 99354 USA; Cho, Jaephil [School of Energy and Chemical Engineering, Green Energy Materials Development Center, Ulsan National Institute of Science and Technology (UNIST), Korea 689-798; Zhang, Ji-Guang [Energy and Environmental Directorate, Pacific Northwest National Laboratory, 902 Battelle Boulevard Richland WA 99354 USA

2016-12-14

The lithium- and manganese-rich (LMR) layered structure cathode exhibit one of the highest specific energy (~900 Wh kg-1) among all the cathode materials. However, the practical applications of LMR cathodes are still hindered by several significant challenges including voltage fade, large initial capacity loss, poor rate capability and limited cycle life. Herein, we review the recent progresses and understandings on the application of LMR cathode materials from practical point of view. Several key parameters of LMR cathodes that affect the LMR/graphite full cell operation are systematically analysed. These factors include the first cycle capacity loss, voltage fade, powder tap density, electrode density of LMR based cathode etc. New approaches to minimize the detrimental effect of these factors are highlighted in this work. We also provided the perspectives for the future research on LMR cathode materials, focusing on addressing the fundamental problems of LMR cathodes while always keeping practical considerations in mind.

Degradation factors of a new long life cathode

International Nuclear Information System (INIS)

Zhang Mingchen; Zhang Honglai; Liu Pukun; Li Yutao

2011-01-01

This paper analyses the degradation factors of a new long life coated impregnated cathode after accelerated life test. The surface state of the cathode is investigated with scanning electron microscope (SEM) as well as the content and variation of the various elements on the surface and the longitudinal section of the cathode are analyzed with Auger electron spectroscopy (AES) before and after the life test. The analyzing results with SEM show that the cathode coating shrinks at the life end and leads to a rise in its work function. The analyzing results with AES show that the percent of the W increases and the active materials Ba decreases on the cathode surface at the life end. Furthermore, there is less Ba underneath the cathode surface but still a lot of Ba in the tungsten matrix at the life end.

Influence of Penning effect on the plasma features in a non-equilibrium atmospheric pressure plasma jet

Energy Technology Data Exchange (ETDEWEB)

Chang, Zhengshi; Zhang, Guanjun [School of Electrical Engineering, Xi' an Jiaotong University, Xi' an 710049 (China); Jiang, Nan; Cao, Zexian, E-mail: zxcao@iphy.ac.cn [Institute of Physics, Chinese Academy of Sciences, Beijing 100190 (China)

2014-03-14

Non-equilibrium atmospheric pressure plasma jet (APPJ) is a cold plasma source that promises various innovative applications. The influence of Penning effect on the formation, propagation, and other physical properties of the plasma bullets in APPJ remains a debatable topic. By using a 10 cm wide active electrode and a frequency of applied voltage down to 0.5 Hz, the Penning effect caused by preceding discharges can be excluded. It was found that the Penning effect originating in a preceding discharge helps build a conductive channel in the gas flow and provide seed electrons, thus the discharge can be maintained at a low voltage which in turn leads to a smaller propagation speed for the plasma bullet. Photographs from an intensified charge coupled device reveal that the annular structure of the plasma plume for He is irrelevant to the Penning ionization process arising from preceding discharges. By adding NH{sub 3} into Ar to introduce Penning effect, the originally filamentous discharge of Ar can display a rather extensive plasma plume in ambient as He. These results are helpful for the understanding of the behaviors of non-equilibrium APPJs generated under distinct conditions and for the design of plasma jet features, especially the spatial distribution and propagation speed, which are essential for application.

Fourier Transform Infrared (FTIR Spectroscopy with Chemometric Techniques for the Classification of Ballpoint Pen Inks

Directory of Open Access Journals (Sweden)

Muhammad Naeim Mohamad Asri

2015-12-01

Full Text Available FTIR spectroscopic techniques have been shown to possess good abilities to analyse ballpoint pen inks. These in-situ techniques involve directing light onto ballpoint ink samples to generate an FTIR spectrum, providing “molecular fingerprints” of the ink samples thus allowing comparison by direct visual comparison. In this study, ink from blue (n=15 and red (n=15 ballpoint pens of five different brands: Kilometrico®, G-Soft®, Stabilo®, Pilot® and Faber Castell® was analysed using the FTIR technique with the objective of establishing a distinctive differentiation according to the brand. The resulting spectra were first compared and grouped manually. Due to the similarities in terms of colour and shade of the inks, distinctive differentiation could not be achieved by means of direct visual comparison. However, when the same spectral data was analysed by Principal Component Analysis (PCA software, distinctive grouping of the ballpoint pen inks was achieved. Our results demonstrate that PCA can be used objectively to investigate ballpoint pen inks of similar colour and more importantly of different brands.

Cathode Composition in a Saltwater Metal-Air Battery

Directory of Open Access Journals (Sweden)

William Shen

2017-01-01

Full Text Available Metal-air batteries consist of a solid metal anode and an oxygen cathode of ambient air, typically separated by an aqueous electrolyte. Here, simple saltwater-based models of aluminum-air and zinc-air cells are used to determine the differences between theoretical cell electric potentials and experimental electric potentials. A substantial difference is observed. It is also found that the metal cathode material is crucial to cell electric potential, despite the cathode not participating in the net reaction. Finally, the material composition of the cathode appears to have a more significant impact on cell potential than the submerged surface area of the cathode.

CRESU studies of electron attachment and Penning ionization at temperatures down to 48 K

International Nuclear Information System (INIS)

Le Garrec, J.L.; Mitchell, J.B.A.; Rowe, B.R.

1996-01-01

The object of the present report is to present results obtained for electron attachment and Penning ionization, obtained with the addition of a Langmuir probe to the measurement apparatus. Measurements of the rate coefficients for electron attachment and Penning ionization are performed using the standard techniques for the flow reactors. Rate coefficients for the Penning ionisation of argon, nitrogen molecule, oxygen molecule by helium metastable are presented. The results obtained concerning the attachment of electrons to SF 6 (non-dissociative), CCl 2 F 2 (producing Cl - ), and CF 3 Br as a function of temperature are presented. The differences observed, and the variation of the value of β below 100 K, provides evidence of the strong influence of the internal state (probably vibrational) of the CF 3 Br molecule on its dissociative attachment

Nanostructured lanthanum manganate composite cathode

DEFF Research Database (Denmark)

Wang, Wei Guo; Liu, Yi-Lin; Barfod, Rasmus

2005-01-01

that the (La1-xSrx)(y)MnO3 +/-delta (LSM) composite cathodes consist of a network of homogenously distributed LSM, yttria-stabilized zirconia (YSZ), and pores. The individual grain size of LSM or YSZ is approximately 100 nm. The degree of contact between cathode and electrolyte is 39% on average. (c) 2005...

Heating of refractory cathodes by high-pressure arc plasmas: II

International Nuclear Information System (INIS)

Benilov, M S; Cunha, M D

2003-01-01

Solitary spots on infinite planar cathodes and diffuse and axially symmetric spot modes on finite cathodes of high-pressure arc discharges are studied in a wide range of arc currents. General features are analysed and extensive numerical results on planar and cylindrical tungsten cathodes of atmospheric-pressure argon arcs are given for currents of up to 100 kA. It is shown, in particular, that the temperature of cathode surface inside a solitary spot varies relatively weakly and may be estimated, to the accuracy of about 200-300 K, without actually solving the thermal conduction equation in the cathode body. Asymptotic behaviour of solutions for finite cathodes in the limiting case of high currents is found and confirmed by numerical results. A general pattern of current-voltage characteristics of various modes on finite cathodes suggested previously on the basis of bifurcation analysis is confirmed. A transition from the spot modes on a finite cathode in the limit of large cathode dimensions to the solitary spot mode on an infinite planar cathode is studied. It is found that the solitary spot mode represents a limiting form of the high-voltage spot mode on a finite cathode. A question of distinguishing between diffuse and spot modes on finite cathodes is considered

Co-deposition of metallic actinides on a solid cathode

Energy Technology Data Exchange (ETDEWEB)

Limmer, S. J.; Williamson, M. A.; Willit, J. L. [Argonne National Laboratory, Argonne (United States)

2008-08-15

The amount of rare earth contamination that will be found in a co-deposit of actinides is a function of the type of cathode used. A non-alloying solid cathode will result in a significantly lower rare earth contamination in the actinide co-deposit than a liquid cadmium cathode. With proper control of the cathode potential vs. a stable reference electrode, co-deposition of uranium with other more electroactive metals has been demonstrated using a non-alloying solid cathode.

Co-deposition of metallic actinides on a solid cathode

International Nuclear Information System (INIS)

Limmer, S. J.; Williamson, M. A.; Willit, J. L.

2008-01-01

The amount of rare earth contamination that will be found in a co-deposit of actinides is a function of the type of cathode used. A non-alloying solid cathode will result in a significantly lower rare earth contamination in the actinide co-deposit than a liquid cadmium cathode. With proper control of the cathode potential vs. a stable reference electrode, co-deposition of uranium with other more electroactive metals has been demonstrated using a non-alloying solid cathode

Impedance of porous IT-SOFC LSCF:CGO composite cathodes

DEFF Research Database (Denmark)

Nielsen, Jimmi; Jacobsen, Torben; Wandel, Marie

2011-01-01

The impedance of technological relevant LSCF:CGO composite IT-SOFC cathodes was studied over a very wide performance range. This was experimentally achieved by impedance measurements on symmetrical cells with three different microstructures in the temperature range 550–850 °C. In order to account...... for the impedance spectra of the poor performing cathodes the Finite-Length-Gerischer (FLG) impedance was derived and applied to the impedance data. The FLG impedance describes for a given microstructure the situation where the cathode is made too thin from a cathode development point of view. The moderate...... performing cathodes showed a slightly suppressed Gerischer impedance, while the impedance spectra of the well performing cathodes showed the presence of an arc due to oxygen gas diffusion. The overall impedance of the well performing cathodes could be described with a slightly suppressed Gerischer impedance...

Preventing Corrosion by Controlling Cathodic Reaction Kinetics

Science.gov (United States)

2016-03-25

3. DATES COVERED (From - To) 09/23/15 - 04/22/16 4. TITLE AND SUBTITLE Sa. CONTRACT NUMBER Preventing Corrosion by Controlling Cathodic Reaction...Preventing corrosion by controlling cathodic reaction kinetics Progress Report for Period: 1 SEP 2015-31 MAR 2016 John Keith Department of...25 March 2016 Preventing corrosion by controlling cathodic reaction kinetics Annual Summary Report: FY16 PI: John Keith, 412-624-7016,jakeith

Knife-edge thin film field emission cathodes

International Nuclear Information System (INIS)

Lee, B.; Demroff, H.P.; Drew, M.M.; Elliott, T.S.; Mazumdar, T.K.; McIntyre, P.M.; Pang, Y.; Smith, D.D.; Trost, H.J.

1993-01-01

Cathodes made of thin-film field emission arrays (FEA) have the advantages of high current density, pulsed emission, and low bias voltage operation. The authors have developed a technology to fabricate knife-edge field emission cathodes on (110) silicon wafers. The emitter geometry is optimized for efficient modulation at high frequency. Cathode fabrication progress and preliminary analysis of their applications in RF power sources are presented

Noble-gas ionization in the ion source with Penning effect

International Nuclear Information System (INIS)

Monchka, D.; Lyatushinskij, A.; Vasyak, A.

1982-01-01

By additional use of that the ion source efficiency can be increased the Penning ionization. The results of estimates of certain coefficients for the processes taking place in the plasma ion sources are presented

Cold cathode diode X-ray source

International Nuclear Information System (INIS)

Cooperstein, G.; Lanza, R.C.; Sohval, A.R.

1983-01-01

A cold cathode diode X-ray source for radiation imaging, especially computed tomography, comprises a rod-like anode and a generally cylindrical cathode, concentric with the anode. The spacing between anode and cathode is so chosen that the diode has an impedance in excess of 100 ohms. The anode may be of tungsten, or of carbon with a tungsten and carbon coating. An array of such diodes may be used with a closely packed array of detectors to produce images of rapidly moving body organs, such as the beating heart. (author)

A new pen device for injection of recombinant human growth hormone: a convenience, functionality and usability evaluation study

Directory of Open Access Journals (Sweden)

Sauer M

2017-12-01

Full Text Available   Maritta Sauer,1 Carole Abbotts2 1Global Strategic Insights, Merck KGaA, Darmstadt, Germany; 2Pharmaceutical Market Research Consultant, London, UK Purpose: Adherence to recombinant human growth hormone (r-hGH is critical to growth and other outcomes in patients with growth disorders, but the requirement for daily injections means that ease of use is an important factor. This study assessed the perceived ease of use and functionality of the prototype of a reusable pen injector (pen device for r-hGH that incorporates several advanced features. Participants and methods: Semi-structured 60-minute qualitative interviews were conducted in 5 countries with 57 health care professionals (HCPs and 30 patients with GH deficiency/caregivers administering r-hGH to patients, including children. HCPs had to be responsible for training in the use of r-hGH pen devices and to see ≥4 r-hGH patients/caregivers per month. Patients/caregivers had to have experience with r-hGH administration for at least 6 months.Results: Thirty-seven (65% of HCPs described the pen device as “simple” or “easy” to use. The aluminum body was generally perceived as attractive, high quality and comfortable to hold and operate. The ease of preparation and use made it suitable for both children and adults. The ability to dial back the r-hGH dose, if entered incorrectly, was mentioned as a major benefit, because other devices need several user steps to reset. Patients/caregivers felt the pen device was easy to use and the injection-feedback features reassured them that the full dose had been given. Overall, 40 (70% HCPs and 16 (52% patients/caregivers were likely to recommend or request the pen device. Moreover, patients/caregivers rated the pen device higher than their current reusable pens and almost equal to the leading disposable device for ease of learning, preparation, administration and ease of use.Conclusion: The prototype pen device successfully met its design

Aspiration of a perforated pen cap: complete tracheal obstruction ...

African Journals Online (AJOL)

Foreign body aspiration is a common but underestimated event in children with potentially fatal outcome. Because of unreliable histories and inconsistent clinical and radiologic findings, diagnosis and treatment can represent a challenge. Inhaled pen caps predispose for complete airway obstruction and are difficult to ...

Research and Development of a New Field Enhanced Low Temperature Thermionic Cathode that Enables Fluorescent Dimming and Loan Shedding without Auxiliary Cathode Heating

Energy Technology Data Exchange (ETDEWEB)

Feng Jin

2009-01-07

This is the final report for project entitled 'Research and development of a new field enhanced low temperature thermionic cathode that enables fluorescent dimming and load shedding without auxiliary cathode heating', under Agreement Number: DE-FC26-04NT-42329. Under this project, a highly efficient CNT based thermionic cathode was demonstrated. This cathode is capable of emitting electron at a current density two order of magnitude stronger then a typical fluorescent cathode at same temperatures, or capable of emitting at same current density but at temperature about 300 C lower than that of a fluorescent cathode. Detailed fabrication techniques were developed including CVD growth of CNTs and sputter deposition of oxide thin films on CNTs. These are mature technologies that have been widely used in industry for large scale materials processing and device fabrications, thus, with further development work, the techniques developed in this project can be scaled-up in manufacturing environment. The prototype cathodes developed in this project were tested in lighting plasma discharge environment. In many cases, they not only lit and sustain the plasma, but also out perform the fluorescent cathodes in key parameters such like cathode fall voltages. More work will be needed to further evaluate more detailed and longer term performance of the prototype cathode in lighting plasma.

High Performance Cathodes for Li-Air Batteries

Energy Technology Data Exchange (ETDEWEB)

Xing, Yangchuan

2013-08-22

The overall objective of this project was to develop and fabricate a multifunctional cathode with high activities in acidic electrolytes for the oxygen reduction and evolution reactions for Li-air batteries. It should enable the development of Li-air batteries that operate on hybrid electrolytes, with acidic catholytes in particular. The use of hybrid electrolytes eliminates the problems of lithium reaction with water and of lithium oxide deposition in the cathode with sole organic electrolytes. The use of acid electrolytes can eliminate carbonate formation inside the cathode, making air breathing Li-air batteries viable. The tasks of the project were focused on developing hierarchical cathode structures and bifunctional catalysts. Development and testing of a prototype hybrid Li-air battery were also conducted. We succeeded in developing a hierarchical cathode structure and an effective bifunctional catalyst. We accomplished integrating the cathode with existing anode technologies and made a pouch prototype Li-air battery using sulfuric acid as catholyte. The battery cathodes contain a nanoscale multilayer structure made with carbon nanotubes and nanofibers. The structure was demonstrated to improve battery performance substantially. The bifunctional catalyst developed contains a conductive oxide support with ultra-low loading of platinum and iridium oxides. The work performed in this project has been documented in seven peer reviewed journal publications, five conference presentations, and filing of two U.S. patents. Technical details have been documented in the quarterly reports to DOE during the course of the project.

Cationic fluorinated polymer binders for microbial fuel cell cathodes

KAUST Repository

Chen, Guang; Wei, Bin; Logan, Bruce E.; Hickner, Michael A.

2012-01-01

Fluorinated quaternary ammonium-containing polymers were used as catalyst binders in microbial fuel cell (MFC) cathodes. The performance of the cathodes was examined and compared to NAFION ® and other sulfonated aromatic cathode catalyst binders using linear sweep voltammetry (LSV), impedance spectroscopy, and performance tests in single chamber air-cathode MFCs. The cathodes with quaternary ammonium functionalized fluorinated poly(arylene ether) (Q-FPAE) binders showed similar current density and charge transfer resistance (R ct) to cathodes with NAFION ® binders. Cathodes containing either of these fluorinated binders exhibited better electrochemical responses than cathodes with sulfonated or quaternary ammonium-functionalized RADEL ® poly(sulfone) (S-Radel or Q-Radel) binders. After 19 cycles (19 d), the power densities of all the MFCs declined compared to the initial cycles due to biofouling at the cathode. MFC cathodes with fluorinated polymer binders (1445 mW m -2, Q-FPAE-1.4-H; 1397 mW m -2, Q-FPAE-1.4-Cl; 1277 mW m -2, NAFION ®; and 1256 mW m -2, Q-FPAE-1.0-Cl) had better performance than those with non-fluorinated polymer binders (880 mW m -2, S-Radel; 670 mW m -2, Q-Radel). There was a 15% increase in the power density using the Q-FPAE binder with a 40% higher ion exchange capacity (Q-FPAE-1.4-H compared to Q-FPAE-1.0-Cl) after 19 cycles of operation, but there was no effect on the power production due to counter ions in the binder (Cl -vs. HCO 3 -). The highest-performance cathodes (NAFION ® and Q-FPAE binders) had the lowest charge transfer resistances (R ct) in fresh and in fouled cathodes despite the presence of thick biofilms on the surface of the electrodes. These results show that fluorinated binders may decrease the penetration of the biofilm and associated biopolymers into the cathode structure, which helps to combat MFC performance loss over time. © 2012 The Royal Society of Chemistry.

Precise mass measurements of exotic nuclei--the SHIPTRAP Penning trap mass spectrometer

International Nuclear Information System (INIS)

Herfurth, F.; Ackermann, D.; Block, M.; Dworschak, M.; Eliseev, S.; Hessberger, F.; Hofmann, S.; Kluge, H.-J.; Maero, G.; Martin, A.; Mazzocco, M.; Rauth, C.; Vorobjev, G.; Blaum, K.; Ferrer, R.; Neidherr, D.; Chaudhuri, A.; Marx, G.; Schweikhard, L.; Neumayr, J.

2007-01-01

The SHIPTRAP Penning trap mass spectrometer has been designed and constructed to measure the mass of short-lived, radioactive nuclei. The radioactive nuclei are produced in fusion-evaporation reactions and separated in flight with the velocity filter SHIP at GSI in Darmstadt. They are captured in a gas cell and transfered to a double Penning trap mass spectrometer. There, the cyclotron frequencies of the radioactive ions are determined and yield mass values with uncertainties ≥4.5·10 -8 . More than 50 nuclei have been investigated so far with the present overall efficiency of about 0.5 to 2%

Field-scale evaluation of water fluxes and manure solution leaching in feedlot pen soils.

Science.gov (United States)

García, Ana R; Maisonnave, Roberto; Massobrio, Marcelo J; Fabrizio de Iorio, Alicia R

2012-01-01

Accumulation of beef cattle manure on feedlot pen surfaces generates large amounts of dissolved solutes that can be mobilized by water fluxes, affecting surface and groundwater quality. Our objective was to examine the long-term impacts of a beef cattle feeding operation on water fluxes and manure leaching in feedlot pens located on sandy loam soils of the subhumid Sandy Pampa region in Argentina. Bulk density, gravimetric moisture content, and chloride concentration were quantified. Rain simulation trials were performed to estimate infiltration and runoff rates. Using chloride ion as a tracer, profile analysis techniques were applied to estimate the soil moisture flux and manure conservative chemical components leaching rates. An organic stratum was found over the surface of the pen soil, separated from the underlying soil by a highly compacted thin layer (the manure-soil interface). The soil beneath the organic layer showed greater bulk density in the A horizon than in the control soil and had greater moisture content. Greater concentrations of chloride were found as a consequence of the partial sealing of the manure-soil interface. Surface runoff was the dominant process in the feedlot pen soil, whereas infiltration was the main process in control soil. Soil moisture flux beneath pens decreased substantially after 15 yr of activity. The estimated minimum leaching rate of chloride was 13 times faster than the estimated soil moisture flux. This difference suggests that chloride ions are not exclusively transported by advective flow under our conditions but also by solute diffusion and preferential flow. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Human factors engineering and design validation for the redesigned follitropin alfa pen injection device.

Science.gov (United States)

Mahony, Mary C; Patterson, Patricia; Hayward, Brooke; North, Robert; Green, Dawne

2015-05-01

To demonstrate, using human factors engineering (HFE), that a redesigned, pre-filled, ready-to-use, pre-asembled follitropin alfa pen can be used to administer prescribed follitropin alfa doses safely and accurately. A failure modes and effects analysis identified hazards and harms potentially caused by use errors; risk-control measures were implemented to ensure acceptable device use risk management. Participants were women with infertility, their significant others, and fertility nurse (FN) professionals. Preliminary testing included 'Instructions for Use' (IFU) and pre-validation studies. Validation studies used simulated injections in a representative use environment; participants received prior training on pen use. User performance in preliminary testing led to IFU revisions and a change to outer needle cap design to mitigate needle stick potential. In the first validation study (49 users, 343 simulated injections), in the FN group, one observed critical use error resulted in a device design modification and another in an IFU change. A second validation study tested the mitigation strategies; previously reported use errors were not repeated. Through an iterative process involving a series of studies, modifications were made to the pen design and IFU. Simulated-use testing demonstrated that the redesigned pen can be used to administer follitropin alfa effectively and safely.

Pervasive liquid metal based direct writing electronics with roller-ball pen

Directory of Open Access Journals (Sweden)

Yi Zheng

2013-11-01

Full Text Available A roller-ball pen enabled direct writing electronics via room temperature liquid metal ink was proposed. With the rolling to print mechanism, the metallic inks were smoothly written on flexible polymer substrate to form conductive tracks and electronic devices. The contact angle analyzer and scanning electron microscope were implemented to disclose several unique inner properties of the obtained electronics. An ever high writing resolution with line width and thickness as 200 μm and 80 μm, respectively was realized. Further, with the administration of external writing pressure, GaIn24.5 droplets embody increasing wettability on polymer which demonstrates the pervasive adaptability of the roller-ball pen electronics.

Properties of H- and D- beams from magnetron and Penning sources

International Nuclear Information System (INIS)

Sluyters, T.; Kovarik, V.

1979-01-01

The quality of negative hydrogen isotope beams are evaluated after extraction from magnetron and Penning sources. The general conclusions of these measurements are that: (a) the beam quality from these plasma sources are adequate for the transport of high current negative ion beams in bending magnets; (b) there is evidence of practically complete space charge neutralization in the drift space beyond the extractor; (c) the beam performance from the Penning source appears to be better compared with the magnetron source; and (d) it is likely that the high electric field gradient and a concave ion emission boundary are responsible for a beam cross-over near the anode aperture, which causes beam divergence practically independent of the extraction geometry

Development and evaluation of carbon and binder loading in low-cost activated carbon cathodes for air-cathode microbial fuel cells

KAUST Repository

Wei, Bin; Tokash, Justin C.; Chen, Guang; Hickner, Michael A.; Logan, Bruce E.

2012-01-01

Activated carbon (AC) air cathodes were constructed using variable amounts of carbon (43-171 mg cm-2) and an inexpensive binder (10 wt% polytetrafluoroethylene, PTFE), and with or without a porous cloth wipe-based diffusion layer (DL) that was sealed with PDMS. The cathodes with the highest AC loading of 171 mg cm-2, and no diffusion layer, produced 1255 ± 75 mW m-2 and did not appreciably vary in performance after 1.5 months of operation. Slightly higher power densities were initially obtained using 100 mg cm-2 of AC (1310 ± 70 mW m-2) and a PDMS/wipe diffusion layer, although the performance of this cathode decreased to 1050 ± 70 mW m-2 after 1.5 months, and 1010 ± 190 mW m-2 after 5 months. AC loadings of 43 mg cm-2 and 100 mg cm-2 did not appreciably affect performance (with diffusion layers). MFCs with the Pt catalyst and Nafion binder initially produced 1295 ± 13 mW m-2, but the performance decreased to 930 ± 50 mW m -2 after 1.5 months, and then to 890 ± 20 mW m-2 after 5 months. Cathode performance was optimized for all cathodes by using the least amount of PTFE binder (10%, in tests using up to 40%). These results provide a method to construct cathodes for MFCs that use only inexpensive AC and a PTFE, while producing power densities similar to those of Pt/C cathodes. The methods used here to make these cathodes will enable further tests on carbon materials in order to optimize and extend the lifetime of AC cathodes in MFCs. © 2012 The Royal Society of Chemistry.

High Performance Fe-Co Based SOFC Cathodes

DEFF Research Database (Denmark)

Kammer Hansen, Kent; Hansen, Karin Vels; Mogensen, Mogens Bjerg

2010-01-01

With the aim of reducing the temperature of the solid oxide fuel cell (SOFC), a new high-performance perovskite cathode has been developed. An area-specific resistance (ASR) as low as 0.12 Ωcm2 at 600 °C was measured by electrochemical impedance spectroscopy (EIS) on symmetrical cells. The cathode...... is a composite between (Gd0.6Sr0.4)0.99Fe0.8Co0.2O3-δ (GSFC) and Ce0.9Gd0.1O1.95 (CGO10). Examination of the microstructure of the cathodes by scanning electron microscopy (SEM) revealed a possibility of further optimisation of the microstructure in order to increase the performance of the cathodes. It also...... seems that an adjustment of the sintering temperature will make a lowering of the ASR value possible. The cathodes were compatible with ceria-based electrolytes but reacted to some extent with zirconia-based electrolytes depending on the sintering temperature....

Model of dopant action in oxide cathodes

International Nuclear Information System (INIS)

Engelsen, Daniel den; Gaertner, Georg

2005-01-01

The paper describes an electrochemical model, which largely explains the formation of Ba in the oxide cathode at activation and normal operation. In a non-doped oxide cathode electrolysis of BaO is, besides the exchange reaction from the activators in the cathode nickel, an important source of Ba. By doping with rare earth oxides the conductivity of the oxide layer increases, which implies that the potential difference during current drawing over the oxide layer becomes lower and electrolysis of BaO is suppressed. This implies that the part of the electronic conductivity of the (Ba,Sr)O layer induced by the dopants also controls the sensitivity for poisoning: the higher the dopant level, the larger the sensitivity for poisoning. Furthermore, the suppression of electrolysis during normal operation largely explains why doped oxide cathodes have a better life performance than non-doped cathodes. Finally a hypothesis on the enhancement of sintering upon doping is presented

Manganese Dioxide As Rechargeable Magnesium Battery Cathode

International Nuclear Information System (INIS)

Ling, Chen; Zhang, Ruigang

2017-01-01

Rechargeable magnesium battery (rMB) has received increased attention as a promising alternative to current Li-ion technology. However, the lack of appropriate cathode that provides high-energy density and good sustainability greatly hinders the development of practical rMBs. To date, the successful Mg 2+ -intercalation was only achieved in only a few cathode hosts, one of which is manganese dioxide. This review summarizes the research activity of studying MnO 2 in magnesium cells. In recent years, the cathodic performance of MnO 2 was impressively improved to the capacity of >150–200 mAh g −1 at voltage of 2.6–2.8 V with cyclability to hundreds or more cycles. In addition to reviewing electrochemical performance, we sketch a mechanistic picture to show how the fundamental understanding about MnO 2 cathode has been changed and how it paved the road to the improvement of cathode performance.

Manganese Dioxide As Rechargeable Magnesium Battery Cathode

Energy Technology Data Exchange (ETDEWEB)

Ling, Chen, E-mail: chen.ling@toyota.com; Zhang, Ruigang [Toyota Research Institute of North America, Ann Arbor, MI (United States)

2017-11-03

Rechargeable magnesium battery (rMB) has received increased attention as a promising alternative to current Li-ion technology. However, the lack of appropriate cathode that provides high-energy density and good sustainability greatly hinders the development of practical rMBs. To date, the successful Mg{sup 2+}-intercalation was only achieved in only a few cathode hosts, one of which is manganese dioxide. This review summarizes the research activity of studying MnO{sub 2} in magnesium cells. In recent years, the cathodic performance of MnO{sub 2} was impressively improved to the capacity of >150–200 mAh g{sup −1} at voltage of 2.6–2.8 V with cyclability to hundreds or more cycles. In addition to reviewing electrochemical performance, we sketch a mechanistic picture to show how the fundamental understanding about MnO{sub 2} cathode has been changed and how it paved the road to the improvement of cathode performance.

Development of compact size penning ion source for compact neutron generator.

Science.gov (United States)

Das, Basanta Kumar; Shyam, Anurag

2008-12-01

For long-life operation, easy to mount and compact in size penning type ion sources are widely used in different fields of research such as neutron generators, material research, and surface etching. One penning type ion source has been developed in our laboratory. Applying high voltage of 2 kV between two oppositely biased electrodes and using permanent magnet of 500 gauss magnetic field along the axis, we had produced the glow discharge in the plasma region. The performance of this source was investigated using nitrogen gas. Deuterium ions were produced and extracted on the basis of chosen electrodes and the angle of extraction. Using a single aperture plasma electrode, the beam was extracted along the axial direction. The geometry of plasma electrode is an important factor for the efficient extraction of the ions from the plasma ion source. The extracted ion current depends upon the shape of the plasma meniscus. A concave shaped plasma meniscus produces converged ion beam. The convergence of extracted ions is related to the extraction electrode angle. The greater the angle, the more the beam converges. We had studied experimentally this effect with a compact size penning ion source. The detailed comparison among the different extraction geometry and different electrode angle are discussed in this paper.

Separation of Electrolytic Reduction Product from Stainless Steel Wire Mesh Cathode Basket via Salt Draining and Reuse of the Cathode Basket

Directory of Open Access Journals (Sweden)

Eun-Young Choi

2017-01-01

Full Text Available We demonstrated that the metallic product obtained after electrolytic reduction (also called oxide reduction (OR can be simply separated from a stainless steel wire mesh cathode basket only by using a salt drain. First, the OR run of a simulated oxide fuel (0.6 kg/batch was conducted in a molten Li2O–LiCl salt electrolyte at 650°C. The simulated oxide fuel of the porous cylindrical pellets was used as a cathode by loading a stainless steel wire mesh cathode basket. Platinum was employed as an anode. After the electrolysis, the residual salt of the cathode basket containing the reduction product was drained by placing it at gas phase above the molten salt using a holder. Then, at a room temperature, the complete separation of the reduction product from the cathode basket was achieved by inverting it without damaging or deforming the basket. Finally, the emptied cathode basket obtained after the separation was reused for the second OR run by loading a fresh simulated oxide fuel. We also succeeded in the separation of the metallic product from the reused cathode basket for the second OR run.

Progress of air-breathing cathode in microbial fuel cells

Science.gov (United States)

Wang, Zejie; Mahadevan, Gurumurthy Dummi; Wu, Yicheng; Zhao, Feng

2017-07-01

Microbial fuel cell (MFC) is an emerging technology to produce green energy and vanquish the effects of environmental contaminants. Cathodic reactions are vital for high electrical power density generated from MFCs. Recently tremendous attentions were paid towards developing high performance air-breathing cathodes. A typical air-breathing cathode comprises of electrode substrate, catalyst layer, and air-diffusion layer. Prior researches demonstrated that each component influenced the performance of air-breathing cathode MFCs. This review summarized the progress in development of the individual component and elaborated main factors to the performance of air-breathing cathode.

Aspiration of a perforated pen cap: complete tracheal obstruction ...

African Journals Online (AJOL)

Keywords: children, flexible bronchoscopy, Fogarty catheter, foreign body aspiration, pen cap, rigid ... plastic foreign body with central perforation occluding the trachea in supracarinal ... venous steroids and was discharged home on postoperative day 1 without ... history may not be as reliable, if not witnessed by an adult.

Individual and pen-based oral fluid sampling: A welfare-friendly sampling method for group-housed gestating sows.

Science.gov (United States)

Pol, Françoise; Dorenlor, Virginie; Eono, Florent; Eudier, Solveig; Eveno, Eric; Liégard-Vanhecke, Dorine; Rose, Nicolas; Fablet, Christelle

2017-11-01

The aims of this study were to assess the feasibility of individual and pen-based oral fluid sampling (OFS) in 35 pig herds with group-housed sows, compare these methods to blood sampling, and assess the factors influencing the success of sampling. Individual samples were collected from at least 30 sows per herd. Pen-based OFS was performed using devices placed in at least three pens for 45min. Information related to the farm, the sows, and their living conditions were collected. Factors significantly associated with the duration of sampling and the chewing behaviour of sows were identified by logistic regression. Individual OFS took 2min 42s on average; the type of floor, swab size, and operator were associated with a sampling time >2min. Pen-based OFS was obtained from 112 devices (62.2%). The type of floor, parity, pen-level activity, and type of feeding were associated with chewing behaviour. Pen activity was associated with the latency to interact with the device. The type of floor, gestation stage, parity, group size, and latency to interact with the device were associated with a chewing time >10min. After 15, 30 and 45min of pen-based OFS, 48%, 60% and 65% of the sows were lying down, respectively. The time spent after the beginning of sampling, genetic type, and time elapsed since the last meal were associated with 50% of the sows lying down at one time point. The mean time to blood sample the sows was 1min 16s and 2min 52s if the number of operators required was considered in the sampling time estimation. The genetic type, parity, and type of floor were significantly associated with a sampling time higher than 1min 30s. This study shows that individual OFS is easy to perform in group-housed sows by a single operator, even though straw-bedded animals take longer to sample than animals housed on slatted floors, and suggests some guidelines to optimise pen-based OFS success. Copyright © 2017 Elsevier B.V. All rights reserved.

Joule heat generation in thermionic cathodes of high-pressure arc discharges

Energy Technology Data Exchange (ETDEWEB)

Benilov, M. S.; Cunha, M. D. [Departamento de Fisica, CCCEE, Universidade da Madeira, Largo do Municipio, 9000 Funchal (Portugal)

2013-02-14

The nonlinear surface heating model of plasma-cathode interaction in high-pressure arcs is extended to take into account the Joule effect inside the cathode body. Calculation results are given for different modes of current transfer to tungsten cathodes of different configurations in argon plasmas of atmospheric or higher pressures. Special attention is paid to analysis of energy balances of the cathode and the near-cathode plasma layer. In all the cases, the variation of potential inside the cathode is much smaller than the near-cathode voltage drop. However, this variation can be comparable to the volt equivalent of the energy flux from the plasma to the cathode and then the Joule effect is essential. Such is the case of the diffuse and mixed modes on rod cathodes at high currents, where the Joule heating causes a dramatic change of thermal and electrical regimes of the cathode. The Joule heating has virtually no effect over characteristics of spots on rod and infinite planar cathodes.

Quadrupole deflector of the double Penning trap system MLLTRAP

Energy Technology Data Exchange (ETDEWEB)

Gartzke, Eva; Kolhinen, Veli; Habs, Dietrich; Neumayr, Juergen; Schuermann, Christian; Szerypo, Jerzy; Thirolf, Peter [Fakultaet fuer Physik, LMU Muenchen, Garching (Germany); Maier-Leibnitz Laboratory, Garching (Germany)

2009-07-01

A cylindrical double Penning trap has been installed and successfully commissioned at the Maier-Leibnitz Laboratory in Garching. This trap system has been designed to isobarically purify low energy ion beams and perform highly accurate mass measurements. An electrostatic quadrupole deflector has been designed and installed at the injection line of the Penning trap system enabling a simultaneous use of an online ion beam with reference ions from an offline ion source. Alternatively two offline sources can be used concurrently e.g. an {alpha} recoil sources providing heavy radioactive species (e.g {sup 240}U) together with reference mass ions (which in the future will be e.g. a carbon cluster ion source). The bender has been designed for beam energies up to 1 keV with q/A ratios 1/1-1/250. This presentation shows the technical design and the operating parameters of the quadrupole beam bender and its implementation at the MLLTRAP system.

About the measurements systems with pen and thermoluminescent dosemeters

International Nuclear Information System (INIS)

Cortes I, M.E.; Ramirez G, F.P.

1998-01-01

In this work it is presented dosimetric data obtained with pen and thermoluminescent dosemeters, which are used by the Occupational Exposure Personnel (OEP) of the Mexican Petroleum Institute (IMP)(1). It was marked several great characteristics as for example, the differences among units which use one and another dosemeter type. Likewise, it is given to know diverse problems that were had in the IMP at relating the data obtained with these dosemeters (which utilizes OEP) and the ICRP 60 recommendations 1990. One of the most important difficulties is to satisfy the recommended limits by ICRP, particularly those that are referring to the units and their complex calculations. With respect to the unities, the ICRP makes reference at the concepts 'dose equivalent' and 'effective dose' with the sievert unit, that the General Regulations for Radiological Safety associates with 'dose equivalent' and 'effective dose equivalent'. It was illustrated the type of dosimetric statistics which are obtained with the TLD lectures and a OEP pen dosemeter during 1997. (Author)

Rf Gun with High-Current Density Field Emission Cathode

International Nuclear Information System (INIS)

Jay L. Hirshfield

2005-01-01

High current-density field emission from an array of carbon nanotubes, with field-emission-transistor control, and with secondary electron channel multiplication in a ceramic facing structure, have been combined in a cold cathode for rf guns and diode guns. Electrodynamic and space-charge flow simulations were conducted to specify the cathode configuration and range of emission current density from the field emission cold cathode. Design of this cathode has been made for installation and testing in an existing S-band 2-1/2 cell rf gun. With emission control and modulation, and with current density in the range of 0.1-1 kA/cm2, this cathode could provide performance and long-life not enjoyed by other currently-available cathodes

Using cathode spacers to minimize reactor size in air cathode microbial fuel cells

KAUST Repository

Yang, Qiao

2012-04-01

Scaling up microbial fuel cells (MFCs) will require more compact reactor designs. Spacers can be used to minimize the reactor size without adversely affecting performance. A single 1.5mm expanded plastic spacer (S1.5) produced a maximum power density (973±26mWm -2) that was similar to that of an MFC with the cathode exposed directly to air (no spacer). However, a very thin spacer (1.3mm) reduced power by 33%. Completely covering the air cathode with a solid plate did not eliminate power generation, indicating oxygen leakage into the reactor. The S1.5 spacer slightly increased columbic efficiencies (from 20% to 24%) as a result of reduced oxygen transfer into the system. Based on operating conditions (1000ς, CE=20%), it was estimated that 0.9Lh -1 of air would be needed for 1m 2 of cathode area suggesting active air flow may be needed for larger scale MFCs. © 2012 Elsevier Ltd.

Polymer coatings as separator layers for microbial fuel cell cathodes

KAUST Repository

Watson, Valerie J.

2011-03-01

Membrane separators reduce oxygen flux from the cathode into the anolyte in microbial fuel cells (MFCs), but water accumulation and pH gradients between the separator and cathode reduces performance. Air cathodes were spray-coated (water-facing side) with anion exchange, cation exchange, and neutral polymer coatings of different thicknesses to incorporate the separator into the cathode. The anion exchange polymer coating resulted in greater power density (1167 ± 135 mW m-2) than a cation exchange coating (439 ± 2 mW m-2). This power output was similar to that produced by a Nafion-coated cathode (1114 ± 174 mW m-2), and slightly lower than the uncoated cathode (1384 ± 82 mW m-2). Thicker coatings reduced oxygen diffusion into the electrolyte and increased coulombic efficiency (CE = 56-64%) relative to an uncoated cathode (29 ± 8%), but decreased power production (255-574 mW m-2). Electrochemical characterization of the cathodes ex situ to the MFC showed that the cathodes with the lowest charge transfer resistance and the highest oxygen reduction activity produced the most power in MFC tests. The results on hydrophilic cathode separator layers revealed a trade off between power and CE. Cathodes coated with a thin coating of anion exchange polymer show promise for controlling oxygen transfer while minimally affecting power production. © 2010 Elsevier B.V. All rights reserved.

2013 Estorm - Invited Paper - Cathode Materials Review

Energy Technology Data Exchange (ETDEWEB)

Daniel, Claus [ORNL; Mohanty, Debasish [ORNL; Li, Jianlin [ORNL; Wood III, David L [ORNL

2014-01-01

The electrochemical potential of cathode materials defines the positive side of the terminal voltage of a battery. Traditionally, cathode materials are the energy-limiting or voltage-limiting electrode. One of the first electrochemical batteries, the voltaic pile invented by Alessandro Volta in 1800 (Phil. Trans. Roy. Soc. 90, 403 431) had a copper-zinc galvanic element with a terminal voltage of 0.76 V. Since then, the research community has increased capacity and voltage for primary (nonrechargeable) batteries and round-trip efficiency for secondary (rechargeable) batteries. Successful secondary batteries have been the lead acid with a lead oxide cathode and a terminal voltage of 2.1 V and later the NiCd with a nickel(III) oxide hydroxide cathode and a 1.2 V terminal voltage. The relatively low voltage of those aqueous systems and the low round-trip efficiency due to activation energies in the conversion reactions limited their use. In 1976, Wittingham (J. Electrochem. Soc., 123, 315) and Besenhard (J Power Sources 1(3), 267) finally enabled highly reversible redox reactions by intercalation of lithium ions instead of by chemical conversion. In 1980, Goodenough and Mizushima (Mater. Res. Bull. 15, 783 789) demonstrated a high-energy and high-power LiCoO2 cathode, allowing for an increase of terminal voltage far beyond 3 V. Over the past four decades, the international research community has further developed cathode materials of many varieties. Current state-of-the-art cathodes demonstrate voltages beyond any known electrolyte stability window, bringing electrolyte research once again to the forefront of battery research.

The recovery of zinc from hot galvanizing slag in an anion-exchange membrane electrolysis reactor

Energy Technology Data Exchange (ETDEWEB)

Ren Xiulian [College of Ocean, Harbin Institute of Technology at Weihai, Weihai 264209 (China); Wei Qifeng, E-mail: weiqifeng163@163.com [College of Ocean, Harbin Institute of Technology at Weihai, Weihai 264209 (China); Hu Surong; Wei Sijie [College of Ocean, Harbin Institute of Technology at Weihai, Weihai 264209 (China)

2010-09-15

This paper reports the optimization of the process parameters for recovery of zinc from hot galvanizing slag in an anion-exchange membrane electrolysis reactor. The experiments were carried out in an ammoniacal ammonium chloride system. The influence of composition of electrolytes, pH, stirring rate, current density and temperature, on cathodic current efficiency, specific power consumption and anodic dissolution of Zn were investigated. The results indicate that the cathode current efficiency increases and the hydrogen evolution decreased with increasing the cathode current density. The partial current for electrodeposition of Zn has liner relationship with {omega}{sup 1/2} ({omega}: rotation rate). The highest current efficiency for dissolving zinc was obtained when NH{sub 4}Cl concentration was 53.46 g L{sup -1} and the anodic dissolution of zinc was determined by mass transfer rate at stirring rate 0-300 r min{sup -1}. Increase in temperature benefits to improve CE and dissolution of Zn, and reduce cell voltage. Initial pH of electrolytes plays an important role in the deposition and anodic dissolution of Zn. The results of single factor experiment show that about 50% energy consumption was saved for electrodeposition of Zn in the anion-exchange membrane electrolysis reactor.

The recovery of zinc from hot galvanizing slag in an anion-exchange membrane electrolysis reactor.

Science.gov (United States)

Ren, Xiulian; Wei, Qifeng; Hu, Surong; Wei, Sijie

2010-09-15

This paper reports the optimization of the process parameters for recovery of zinc from hot galvanizing slag in an anion-exchange membrane electrolysis reactor. The experiments were carried out in an ammoniacal ammonium chloride system. The influence of composition of electrolytes, pH, stirring rate, current density and temperature, on cathodic current efficiency, specific power consumption and anodic dissolution of Zn were investigated. The results indicate that the cathode current efficiency increases and the hydrogen evolution decreased with increasing the cathode current density. The partial current for electrodeposition of Zn has liner relationship with omega(1/2) (omega: rotation rate). The highest current efficiency for dissolving zinc was obtained when NH(4)Cl concentration was 53.46 g L(-1) and the anodic dissolution of zinc was determined by mass transfer rate at stirring rate 0-300 r min(-1). Increase in temperature benefits to improve CE and dissolution of Zn, and reduce cell voltage. Initial pH of electrolytes plays an important role in the deposition and anodic dissolution of Zn. The results of single factor experiment show that about 50% energy consumption was saved for electrodeposition of Zn in the anion-exchange membrane electrolysis reactor. Copyright 2010 Elsevier B.V. All rights reserved.

Measuring current emission and work functions of large thermionic cathodes

International Nuclear Information System (INIS)

Fortgang, C.M.

2001-01-01

As one component of the nations Stockpile Stewardship program, Los Alamos National Laboratory is constructing a 20 MeV, 2 kA (with a 4 kA upgrade capability), 3ps induction linac for doing x-ray radiography of explosive devices. The linac is one leg of a facility called the Dual-Axis Radiography Hydrodynamic Test Facility (DARHT). The electron gun is designed to operate at 3.2 MV. The gun is a Pierce type design and uses a 6.5' cathode for 2 kA operation and an 8' cathode for 4 kA operation. We have constructed a small facility called the Cathode Test Stand (CTS) to investigate engineering and physics issues regarding large thermionic dispenser-cathodes. In particular, we have looked at the issues of temperature uniformity on the cathode surface and cathode quality as measured by its work function. We have done thermal imaging of both 8' and 6.5' cathodes. Here we report on measurements of the cathode work function, both the average value and how it vanes across the face of the cathode.

Hollow Cathode Assembly Development for the HERMeS Hall Thruster

Science.gov (United States)

Sarver-Verhey, Timothy R.; Kamhawi, Hani; Goebel, Dan M.; Polk, James E.; Peterson, Peter Y.; Robinson, Dale A.

2016-01-01

To support the operation of the HERMeS 12.5 kW Hall Thruster for NASA's Asteroid Redirect Robotic Mission, hollow cathodes using emitters based on barium oxide impregnate and lanthanum hexaboride are being evaluated through wear-testing, performance characterization, plasma modeling, and review of integration requirements. This presentation will present the development approach used to assess the cathode emitter options. A 2,000-hour wear-test of development model Barium Oxide (BaO) hollow cathode is being performed as part of the development plan. Specifically this test is to identify potential impacts cathode emitter life during operation in the HERMeS thruster. The cathode was operated with a magnetic field-equipped anode that simulates the HERMeS hall thruster operating environment. Cathode discharge performance has been stable with the device accumulating 743 hours at the time of this report. Observed voltage changes are attributed to keeper surface condition changes during testing. Cathode behavior during characterization sweeps exhibited stable behavior, including cathode temperature. The details of the cathode assembly operation of the wear-test will be presented.

Second Generation Electronic Nicotine Delivery System Vape Pen Exposure Generalizes as a Smoking Cue.

Science.gov (United States)

King, Andrea C; Smith, Lia J; McNamara, Patrick J; Cao, Dingcai

2018-01-05

Second generation electronic nicotine delivery systems (ENDS; also known as e-cigarettes, vaporizers or vape pens) are designed for a customized nicotine delivery experience and have less resemblance to regular cigarettes than first generation "cigalikes." The present study examined whether they generalize as a conditioned cue and evoke smoking urges or behavior in persons exposed to their use. Data were analyzed in N = 108 young adult smokers (≥5 cigarettes per week) randomized to either a traditional combustible cigarette smoking cue or a second generation ENDS vaping cue in a controlled laboratory setting. Cigarette and e-cigarette urge and desire were assessed pre- and post-cue exposure. Smoking behavior was also explored in a subsample undergoing a smoking latency phase after cue exposure (N = 26). The ENDS vape pen cue evoked both urge and desire for a regular cigarette to a similar extent as that produced by the combustible cigarette cue. Both cues produced similar time to initiate smoking during the smoking latency phase. The ENDS vape pen cue elicited smoking urge and desire regardless of ENDS use history, that is, across ENDS naїve, lifetime or current users. Inclusion of past ENDS or cigarette use as covariates did not significantly alter the results. These findings demonstrate that observation of vape pen ENDS use generalizes as a conditioned cue to produce smoking urge, desire, and behavior in young adult smokers. As the popularity of these devices may eventually overtake those of first generation ENDS cigalikes, exposure effects will be of increasing importance. This study shows that passive exposure to a second generation ENDS vape pen cue evoked smoking urge, desire, and behavior across a range of daily and non-daily young adult smokers. Smoking urge and desire increases after vape pen exposure were similar to those produced by exposure to a first generation ENDS cigalike and a combustible cigarette, a known potent cue. Given the increasing

Study of argon-based Penning gas mixtures for use in proportional counters

International Nuclear Information System (INIS)

Agrawal, P.C.; Ramsey, B.D.; Weisskopf, M.C.

1989-01-01

Results from an experimental investigation of three Penning gas mixtures, namely argon-acetylene (Ar-C 2 H 2 ), argon-xenon (Ar-Xe) and argon-xenon-trimethylamine (Ar-Xe-TMA), are reported. The measurements, carried out in cylindrical geometry as well as parallel plate geometry detectors, demonstrate that the Ar-C 2 H 2 mixtures show a significant Penning effect even at an acetylene concentration of 10% and provide the best energy resolution among all the argon-based gas mixtures (≤13% FWHM at 5.9 keV and 6.7% at 22.2 keV). In the parallel plate detector the Ar-C 2 H 2 fillings provide a resolution of ≅7% FWHM at 22.2 keV up to a gas gain of at least ≅10 4 . The nonmetastable Penning mixture Ar-Xe provides the highest gas gain among all the argon-based gas mixtures and is well suited for use in long-duration space-based experiments. Best results are obtained with 5% and 20% Xe in Ar, the energy resolution being ≅7% FWHM at 22.2 keV and ≅4.5% at 59.6 keV for gas gain 3 . Addition of ≥1% TMA to an 80% Ar-20% Xe mixture produces a dramatic increase in gas gain but the energy resolution remains unaffected (≅7% FWHM at 22.2 keV). This increase in gas gain is attributed to the occurrence of a Penning effect between Xe and TMA, the ionization potential of TMA being 8.3 eV, just below the xenon metastable potential of 8.39 eV. (orig.)

Temperature and body weight affect fouling of pig pens.

Science.gov (United States)

Aarnink, A J A; Schrama, J W; Heetkamp, M J W; Stefanowska, J; Huynh, T T T

2006-08-01

Fouling of the solid lying area in pig housing is undesirable for reasons of animal welfare, animal health, environmental pollution, and labor costs. In this study the influence of temperature on the excreting and lying behavior of growing-finishing pigs of different BW (25, 45, 65, 85, or 105 kg) was studied. Ten groups of 5 pigs were placed in partially slatted pens (60% solid concrete, 40% metal-slatted) in climate respiration chambers. After an adaptation period, temperatures were raised daily for 9 d. Results showed that above certain inflection temperatures (IT; mean 22.6 degrees C, SE = 0.78) the number of excretions (relative to the total number of excretions) on the solid floor increased with temperature (mean increase 9.7%/ degrees C, SE = 1.41). Below the IT, the number of excretions on the solid floor was low and not influenced by temperature (mean 13.2%, SE = 3.5). On average, the IT for excretion on the solid floor decreased with increasing BW, from approximately 25 degrees C at 25 kg to 20 degrees C at 100 kg of BW (P temperature also affected the pattern and postural lying. The temperature at which a maximum number of pigs lay on the slatted floor (i.e., the IT for lying) decreased from approximately 27 degrees C at 25 kg to 23 degrees C at 100 kg of BW (P temperatures, pigs lay more on their sides and less against other pigs (P Temperature affects lying and excreting behavior of growing-finishing pigs in partially slatted pens. Above certain IT, pen fouling increases linearly with temperature. Inflection temperatures decrease at increasing BW.

Preparation and characterisation of irradiated crab chitosan and New Zealand Arrow squid pen chitosan

International Nuclear Information System (INIS)

Shavandi, Amin; Bekhit, Adnan A.; Bekhit, Alaa El-Din A.; Sun, Zhifa; Ali, M. Azam

2015-01-01

The properties of chitosan from Arrow squid (Nototodarus sloanii) pen (CHS) and commercial crab shell (CHC) were investigated using FTIR, DSC, SEM and XRD before and after irradiation at the dose of 28 kGy in the presence or absence of 5% water. Also, the viscosity, deacetylation degree, water and oil holding capacities, colour and antimicrobial activities of the chitosan samples were determined. Irradiation decreased (P < 0.05) the viscosity of CHC from 0.21 to 0.03 Pa s and of CHS from 1.71 to 0.23 Pa s. The inclusion of water had no effect on the viscosity of irradiated chitosan. Irradiation did not affect the degree of deacetylation of CHC, but increased the deacetylation degree of CHS from 72.78 to 82.29% in samples with 5% water. Water and oil holding capacities of CHS (1197.30% and 873.3%, respectively) were higher (P < 0.05) than those found in CHC (340.70% and 264.40%, respectively). The water and oil holding capacities were decreased for both types of chitosan irradiation, but were not affected by the addition of water. Squid pen chitosan was whiter in colour (White Index = 90.06%) compared to CHC (White Index = 83.70%). Generally, the CHC samples (control and irradiated) exhibited better antibacterial activity compared to CHS, but the opposite was observed with antifungal activity. - Highlights: • Chitosan prepared from Arrow squid pens (Nototodarus sloanii). • Chitosan samples were gamma irradiated at 28 kGy. • Squid pen chitosan showed high fat and water uptake capacities compared to crab shell chitosan. • Gamma irradiation enhanced the DDA of squid pen chitosan but not crab shell chitosan.

RF Electron Gun with Driven Plasma Cathode

CERN Document Server

Khodak, Igor

2005-01-01

It's known that RF guns with plasma cathodes based on solid-state dielectrics are able to generate an intense electron beam. In this paper we describe results of experimental investigation of the single cavity S-band RF gun with driven plasma cathode. The experimental sample of the cathode based on ferroelectric ceramics has been designed. Special design of the cathode permits to separate spatially processes of plasma development and electron acceleration. It has been obtained at RF gun output electron beam with particle energy ~500 keV, pulse current of 4 A and pulse duration of 80 ns. Results of experimental study of beam parameters are referred in. The gun is purposed to be applied as the intense electron beam source for electron linacs.

A Transient Model for Fuel Cell Cathode-Water Propagation Behavior inside a Cathode after a Step Potential

Directory of Open Access Journals (Sweden)

Der-Sheng Chan

2010-04-01

Full Text Available Most of the voltage losses of proton exchange membrane fuel cells (PEMFC are due to the sluggish kinetics of oxygen reduction on the cathode and the low oxygen diffusion rate inside the flooded cathode. To simulate the transient flooding in the cathode of a PEMFC, a transient model was developed. This model includes the material conservation of oxygen, vapor, water inside the gas diffusion layer (GDL and micro-porous layer (MPL, and the electrode kinetics in the cathode catalyst layer (CL. The variation of hydrophobicity of each layer generated a wicking effect that moves water from one layer to the other. Since the GDL, MPL, and CL are made of composite materials with different hydrophilic and hydrophobic properties, a linear function of saturation was used to calculate the wetting contact angle of these composite materials. The balance among capillary force, gas/liquid pressure, and velocity of water in each layer was considered. Therefore, the dynamic behavior of PEMFC, with saturation transportation taken into account, was obtained in this study. A step change of the cell voltage was used to illustrate the transient phenomena of output current, water movement, and diffusion of oxygen and water vapor across the entire cathode.

Subcortical BOLD responses during visual sexual stimulation vary as a function of implicit porn associations in women.

Science.gov (United States)

Borg, Charmaine; de Jong, Peter J; Georgiadis, Janniko R

2014-02-01

Lifetime experiences shape people's attitudes toward sexual stimuli. Visual sexual stimulation (VSS), for instance, may be perceived as pleasurable by some, but as disgusting or ambiguous by others. VSS depicting explicit penile-vaginal penetration (PEN) is relevant in this respect, because the act of penetration is a core sexual activity. In this study, 20 women without sexual complaints participated. We used functional magnetic resonance imaging and a single-target implicit association task to investigate how brain responses to PEN were modulated by the initial associations in memory (PEN-'hot' vs PEN-disgust) with such hardcore pornographic stimuli. Many brain areas responded to PEN in the same way they responded to disgust stimuli, and PEN-induced brain activity was prone to modulation by subjective disgust ratings toward PEN stimuli. The relative implicit PEN-disgust (relative to PEN-'hot') associations exclusively modulated PEN-induced brain responses: comparatively negative (PEN-disgust) implicit associations with pornography predicted the strongest PEN-related responses in the basal forebrain (including nucleus accumbens and bed nucleus of stria terminalis), midbrain and amygdala. Since these areas are often implicated in visual sexual processing, the present findings should be taken as a warning: apparently their involvement may also indicate a negative or ambivalent attitude toward sexual stimuli.

Cathode erosion in high-current high-pressure arc

CERN Document Server

Nemchinsky, V A

2003-01-01

Cathode erosion rate was experimentally investigated for two types of arcs: one with tungsten cathode in nitrogen atmosphere and one with hafnium cathode in oxygen atmosphere. Conditions were typical for plasma arc cutting systems: gas pressure from 2 to 5 atm, arc current from 200 to 400 A, gas flow rate from 50 to 130 litre min sup - sup 1. It was found that the actual cathode evaporation rate G is much lower than G sub 0 , the evaporation rate that follows from the Hertz-Knudsen formula: G = nu G sub 0. The difference is because some of the evaporated particles return back to the cathode. For conditions of our experiments, the factor nu could be as low as 0.01. It was shown experimentally that nu depends strongly on the gas flow pattern close to the cathode. In particular, swirling the gas increases nu many times. To explain the influence of gas swirling, model calculations of gas flows were performed. These calculations revealed difference between swirling and non-swirling flows: swirling the gas enhances...

Structured electron beams from nano-engineered cathodes

Energy Technology Data Exchange (ETDEWEB)

Lueangaramwong, A. [NICADD, DeKalb; Mihalcea, D. [NICADD, DeKalb; Andonian, G. [RadiaBeam Tech.; Piot, P. [Fermilab

2017-03-07

The ability to engineer cathodes at the nano-scale have open new possibilities such as enhancing quantum eciency via surface-plasmon excitation, forming ultra-low-emittance beams, or producing structured electron beams. In this paper we present numerical investigations of the beam dynamics associated to this class of cathode in the weak- and strong-field regimes.We finally discuss the possible applications of some of the achievable cathode patterns when coupled with other phase space manipulations.

Demonstration of Ice-Free Cathodic Protection Systems for Water Storage Tanks at Fort Drum: Final Report on Project AR-F-318 for FY05

Science.gov (United States)

2007-06-01

16-inch diameter ductile iron pipe, where inlet and outlet pressures are nominally 100 psi and 50 psi, respectively. A local contractor will hot...P-641-G -- Primer Coating ; Zinc Dust- Zinc Oxide (for Galvanized Surfaces) 1.1.3. Federal Technical Reports. ETL 1110-9-10(FR) – Cathodic Protection...American National Standards Institute (ANSI) Standards. ANSI C80.1 -- Rigid Steel Conduit - Zinc Coated 1.1.6. American Society for Testing

Gradual training of alpacas to the confinement of metabolism pens reduces stress when normal excretion behavior is accommodated.

Science.gov (United States)

Lund, Kirrin E; Maloney, Shane K; Milton, John T B; Blache, Dominique

2012-01-01

Confinement in metabolism pens may provoke a stress response in alpacas that will reduce the welfare of the animal and jeopardize the validity of scientific results obtained in such pens. In this study, we tested a protocol designed to successfully train alpacas to be held in a specially designed metabolism pen so that the animals' confinement would not jeopardize their welfare. We hypothesized that the alpacas would show fewer behaviors associated with a response to stress as training gradually progressed, and that they would adapt to being in the confinement of the metabolism pen. The training protocol was successful at introducing alpacas to the metabolism pens, and it did reduce the incidence of behavioral responses to stress as the training progressed. The success of the training protocol may be attributed to the progressive nature of the training, the tailoring of the protocol to suit alpacas, and the use of positive reinforcement. This study demonstrated that both animal welfare and the validity of the scientific outcomes could be maximized by the gradual training of experimental animals, thereby minimizing the stress imposed on the animals during experimental procedures.

Comparison of bacterial culture and qPCR testing of rectal and pen floor samples as diagnostic approaches to detect enterotoxic Escherichia coli in nursery pigs

DEFF Research Database (Denmark)

Weber, N. R.; Nielsen, J. P.; Hjulsager, Charlotte Kristiane

2017-01-01

Enterotoxigenic E. coli (ETEC) are a major cause of diarrhoea in weaned pigs. The objective of this study was to evaluate the agreement at pen level among three different diagnostic approaches for the detection of ETEC in groups of nursery pigs with diarrhoea. The diagnostic approaches used were...... to determine the quantity of F18 and F4 genes. The study was carried out in three Danish pig herds and included 31 pens with a pen-level diarrhoea prevalence of > 25%, as well as samples from 93 diarrhoeic nursery pigs from these pens. All E. coli isolates were analysed by PCR and classified as ETEC when genes...... was observed between the detection of ETEC by bacterial culture and qPCR in the same pen floor sample in 26 (83.9%, Kappa = 0.679) pens. Conclusion: We observed an acceptable agreement for the detection of ETEC-positive diarrhoeic nursery pigs in pen samples for both bacterial culture of pen floor samples...

Johannes Vermeer and Tom Gouws: textual discourse through pen ...

African Journals Online (AJOL)

Poems such as 'ars poetica' and 'die kantklosser' will be read as speaking paintings of visual texts and visual writing through which an exceptional merger of pen and brush come into being. Keywords: iconicity, tipography, cohesion, visual text, ars poetica, syntactic chiasm, texture, canto. Journal for Language Teaching Vol ...

Evaluation of drop versus trickle-feeding systems for crated or group-penned gestating sows.

Science.gov (United States)

Hulbert, L E; McGlone, J J

2006-04-01

A total of 160 gilts were used to evaluate the effects of pen vs. crated housing systems and drop- vs. trickle-fed feeding systems on sow productivity, occurrence of lesions during farrowing and weaning, immune measures, and behavioral responses during 2 consecutive gestation periods. Of the 160 eligible gilts, 117 farrowed in parity 1, and of those, 72 farrowed in parity 2. The gilts were randomly assigned to represent 1 of 4 factorially arranged treatment groups: pen drop-fed, crate drop-fed, pen trickle-fed, or crate trickle-fed. Replicate blocks were used for each parity with 5 sows per block initially in each treatment. At weaning, sows housed in pens had greater (P trickle-feeding system. Lesions scores and all other productivity measures did not differ among treatments. An interaction was observed for percentage of neutrophil phagocytosis (P trickle-fed sows, but in crates, drop-fed sows had a tendency for lower phagocytosis than trickle-fed sows. All other immune measures were not different among treatments. The occurrence of oral-nasal-facial (ONF) behaviors (chewing, rooting, and rubbing) and active behaviors increased, and lying behavior decreased (P trickle-feeding systems. None of the environments evaluated were associated with significant physiological stress responses among the sows. Thus, sows were able to adapt within each environment through behavioral mechanisms without the need to invoke major physiological adjustments.

Hot Deformation Behavior of Hot-Extruded AA7175 Through Hot Torsion Tests.

Science.gov (United States)

Lee, Se-Yeon; Jung, Taek-Kyun; Son, Hyeon-Woo; Kim, Sang-Wook; Son, Kwang-Tae; Choi, Ho-Joon; Oh, Sang-Ho; Lee, Ji-Woon; Hyun, Soong-Keun

2018-03-01

The hot deformation behavior of hot-extruded AA7175 was investigated with flow curves and processing maps through hot torsion tests. The flow curves and the deformed microstructures revealed that dynamic recrystallization (DRX) occurred in the hot-extruded AA7175 during hot working. The failure strain was highest at medium temperature. This was mainly influenced by the dynamic precipitation of fine rod-shaped MgZn2. The processing map determined the optimal deformation condition for the alloy during hot working.

Plasma-induced field emission study of carbon nanotube cathode

Directory of Open Access Journals (Sweden)

Yi Shen

2011-10-01

Full Text Available An investigation on the plasma-induced field emission (PFE properties of a large area carbon nanotube (CNT cathode on a 2 MeV linear induction accelerator injector is presented. Experimental results show that the cathode is able to emit intense electron beams. Intense electron beams of 14.9–127.8  A/cm^{2} are obtained from the cathode. The CNT cathode desorbs gases from the CNTs during the PFE process. The fast cathode plasma expansion affects the diode perveance. The amount of outgassing is estimated to be 0.06–0.49  Pa·L, and the ratio of outgassing and electron are roughly calculated to be within the range of 170–350 atoms per electron. The effect of the outgassing is analyzed, and the outgassing mass spectrum of the CNT cathode has been studied during the PFE. There is a significant desorption of CO_{2}, N_{2}(CO, and H_{2} gases, which plays an important role during the PFE process. All the experiments demonstrate that the outgassing plays an important role in the formation of the cathode plasma. Moreover, the characteristic turn-on time of the CNT cathode was measured to be 39 ns.

Cathode refunctionalization as a lithium ion battery recycling alternative

Science.gov (United States)

Ganter, Matthew J.; Landi, Brian J.; Babbitt, Callie W.; Anctil, Annick; Gaustad, Gabrielle

2014-06-01

An approach to battery end-of-life (EOL) management is developed involving cathode refunctionalization, which enables remanufacturing of the cathode from EOL materials to regain the electrochemical performance. To date, the optimal end-of-life management of cathode materials is based on economic value and environmental impact which can influence the methods and stage of recycling. Traditional recycling methods can recover high value metal elements (e.g. Li, Co, Ni), but still require synthesis of new cathode from a mix of virgin and recovered materials. Lithium iron phosphate (LiFePO4) has been selected for study as a representative cathode material due to recent mass adoption and limited economic recycling drivers due to the low inherent cost of iron. Refunctionalization of EOL LiFePO4 cathode was demonstrated through electrochemical and chemical lithiation methods where the re-lithiated LiFePO4 regained the original capacity of 150-155 mAh g-1. The environmental impact of the new recycling technique was determined by comparing the embodied energy of cathode material originating from virgin, recycled, and refunctionalized materials. The results demonstrate that the LiFePO4 refunctionalization process, through chemical lithiation, decreases the embodied energy by 50% compared to cathode production from virgin materials.

Surface Characterization of the LCLS RF Gun Cathode

International Nuclear Information System (INIS)

Brachmann, Axel; Decker, Franz-Josef; Ding, Yuantao; Dowell, David; Emma, Paul; Frisch, Josef; Gilevich, Sasha; Hays, Gregory; Hering, Philippe; Huang, Zhirong; Iverson, Richard; Loos, Henrik; Miahnahri, Alan; Nordlund, Dennis; Nuhn, Heinz-Dieter; Pianetta, Piero; Turner, James; Welch, James; White, William; Wu, Juhao; Xiang, Dao

2012-01-01

The first copper cathode installed in the LCLS RF gun was used during LCLS commissioning for more than a year. However, after high charge operation (> 500 pC), the cathode showed a decline of quantum efficiency within the area of drive laser illumination. They report results of SEM, XPS and XAS studies that were carried out on this cathode after it was removed from the gun. X-ray absorption and X-ray photoelectron spectroscopy reveal surface contamination by various hydrocarbon compounds. In addition they report on the performance of the second installed cathode with emphasis on the spatial distribution of electron emission.

Cathode protection for underground steel tanks

International Nuclear Information System (INIS)

Angelovski, Zoran

1998-01-01

Cathodic protection of underground petroleum storage tanks and piping systems is acceptable for both economic and ecological reasons. With out the cathodic protection of underground steel reservoirs, short time after the exploitation, there was a bore as a result of underground corrosion. The bore causes ecological consequences and at the same time its repair needs big investments. Furthermore, there are great number of tanks placed near cities, so in the future this problem needs a special attention in order to preserve ecological surrounding. The topic of this paper is underground corrosion as well as cathodic protection of steel tanks for oil derivatives storage. (author)

9 CFR 309.7 - Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and driveways.

Science.gov (United States)

2010-01-01

...; cleaning and disinfection of infected livestock pens and driveways. 309.7 Section 309.7 Animals and Animal... INSPECTION § 309.7 Livestock affected with anthrax; cleaning and disinfection of infected livestock pens and... followed immediately by a thorough disinfection of the exposed premises by soaking the ground, fences...

Forensic Analysis of Blue Ball point Pen Inks on Questioned Documents by High Performance Thin Layer Chromatography Technique (HPTLC)

International Nuclear Information System (INIS)

Lee, L.C.; Siti Mariam Nunurung; Abdul Aziz Ishak

2014-01-01

Nowadays, crimes related to forged documents are increasing. Any erasure, addition or modification in the document content always involves the use of writing instrument such as ball point pens. Hence, there is an evident need to develop a fast and accurate ink analysis protocol to solve this problem. This study is aimed to determine the discrimination power of high performance thin layer chromatography (HPTLC) technique for analyzing a set of blue ball point pen inks. Ink samples deposited on paper were extracted using methanol and separated via a solvent mixture of ethyl acetate, methanol and distilled water (70: 35: 30, v/ v/ v). In this method, the discrimination power of 89.40 % was achieved, which confirm that the proposed method was able to differentiate a significant number of pen-pair samples. In addition, composition of blue pen inks was found to be homogeneous (RSD < 2.5 %) and the proposed method showed good repeatability and reproducibility (RSD < 3. 0%). As a conclusion, HPTLC is an effective tool to separate blue ball point pen inks. (author)

Oxide Fiber Cathode Materials for Rechargeable Lithium Cells

Science.gov (United States)

Rice, Catherine E.; Welker, Mark F.

2008-01-01

LiCoO2 and LiNiO2 fibers have been investigated as alternatives to LiCoO2 and LiNiO2 powders used as lithium-intercalation compounds in cathodes of rechargeable lithium-ion electrochemical cells. In making such a cathode, LiCoO2 or LiNiO2 powder is mixed with a binder [e.g., poly(vinylidene fluoride)] and an electrically conductive additive (usually carbon) and the mixture is pressed to form a disk. The binder and conductive additive contribute weight and volume, reducing the specific energy and energy density, respectively. In contrast, LiCoO2 or LiNiO2 fibers can be pressed and sintered to form a cathode, without need for a binder or a conductive additive. The inter-grain contacts of the fibers are stronger and have fewer defects than do those of powder particles. These characteristics translate to increased flexibility and greater resilience on cycling and, consequently, to reduced loss of capacity from cycle to cycle. Moreover, in comparison with a powder-based cathode, a fiber-based cathode is expected to exhibit significantly greater ionic and electronic conduction along the axes of the fibers. Results of preliminary charge/discharge-cycling tests suggest that energy densities of LiCoO2- and LiNiO2-fiber cathodes are approximately double those of the corresponding powder-based cathodes.

Study of the hollow cathode plasma electron-gun

International Nuclear Information System (INIS)

Zhang Yonghui; Jiang Jinsheng; Chang Anbi

2003-01-01

For developing a novel high-current, long pulse width electron source, the theoretics and mechanism of the hollow cathode plasma electron-gun are analyzed in detail in this paper, the structure and the physical process of hollow cathode plasma electron-gun are also studied. This gun overcomes the limitations of most high-power microwave tubes, which employ either thermionic cathodes that produce low current-density beams because of the limitation of the space charge, or field-emission cathodes that offer high current density but provide only short pulse width because of plasma closure of the accelerating gap. In the theories studying on hollow cathode plasma electron-gun, the characteristic of the hollow-cathode discharge is introduced, the action during the forming of plasma of the stimulating electrode and the modulating anode are discussed, the movement of electrons and ions and the primary parameters are analyzed, and the formulas of the electric field, beam current density and the stabilization conditions of the beam current are also presented in this paper. The numerical simulation is carried out based on Poisson's equation, and the equations of current continuity and movement. And the optimized result is reported. On this basis, we have designed a hollow-cathode-plasma electron-gun, whose output pulse current is 2 kA, and pulse width is 1 microsecond

Pre-acclimation of a wastewater inoculum to cellulose in an aqueous–cathode MEC improves power generation in air–cathode MFCs

KAUST Repository

Cheng, Shaoan

2011-01-01

Cellulose has been used in two-chamber microbial fuel cells (MFCs), but power densities were low. Higher power densities can be achieved in air-cathode MFCs using an inoculum from a two-chamber, aqueous-cathode microbial electrolysis cell (MEC). Air-cathode MFCs with this inoculum produced maximum power densities of 1070mWm-2 (cathode surface area) in single-chamber and 880mWm-2 in two-chamber MFCs. Coulombic efficiencies ranged from 25% to 50%, and COD removals were 50-70% based on total cellulose removals of 60-80%. Decreasing the reactor volume from 26 to 14mL (while maintaining constant electrode spacing) decreased power output by 66% (from 526 to 180mWm-2) due to a reduction in total mass of cellulose added. These results demonstrate that air-cathode MFCs can produce high power densities with cellulose following proper acclimation of the inoculum, and that organic loading rates are important for maximizing power densities from particulate substrates. © 2010 Elsevier Ltd.

Forensic analysis of ballpoint pen inks using paper spray mass spectrometry.

Science.gov (United States)

da Silva Ferreira, Priscila; Fernandes de Abreu e Silva, Débora; Augusti, Rodinei; Piccin, Evandro

2015-02-07

A novel analytical approach based on paper spray mass spectrometry (PS-MS) is developed for a fast and effective forensic analysis of inks in documents. Ink writings made in ordinary paper with blue ballpoint pens were directly analyzed under ambient conditions without any prior sample preparation. Firstly, the method was explored on a set of distinct pens and the results obtained in the positive ion mode, PS(+)-MS, demonstrated that pens from different brands provide typical profiles. Simple visual inspection of the PS(+)-MS led to the distinction of four different combinations of dyes and additives in the inks. Further discrimination was performed by using the concept of relative ion intensity (RII), owing to the large variability of dyes BV3 and BB26 regarding their demethylated homologues. Following screening and differentiation studies, the composition changes of ink entries subjected to light exposure were also monitored by PS-MS. The results of these tests revealed distinct degradation behaviors which were reflected on the typical chemical profiles of the studied inks, attesting that PS-MS may be also useful to verify the fading of dyes thus allowing the discrimination of entries on a document. As proof of concept experiments, PS-MS was successfully utilized for the analysis of archived documents and characterization of overlapped ink lines made on simulated forged documents.

Status of the Penning trap project in Munich

International Nuclear Information System (INIS)

Szerypo, J.; Kolhinen, V.S.; Gartzke, E.; Habs, D.; Neumayr, J.; Schuermann, C.; Sewtz, M.; Thirolf, P.G.; Bussmann, M.; Schramm, U.

2009-01-01

The MLLTRAP at the Maier-Leibnitz-Laboratory (Garching) is a new Penning trap facility designed to combine several novel technologies to decelerate, charge breed, cool, bunch and purify the reaction products and perform high-accuracy nuclear and atomic mass measurements. It is now in the commissioning phase, achieving a mass-resolving power of about 10 5 in the purification trap for stable ions. (orig.)

Status of the Penning trap project in Munich

Energy Technology Data Exchange (ETDEWEB)

Szerypo, J.; Kolhinen, V.S.; Gartzke, E.; Habs, D.; Neumayr, J.; Schuermann, C.; Sewtz, M.; Thirolf, P.G. [University of Munich (LMU) and Maier-Leibnitz-Laboratory (MLL), Faculty of Physics, Garching (Germany); Bussmann, M.; Schramm, U. [University of Munich (LMU) and Maier-Leibnitz-Laboratory (MLL), Faculty of Physics, Garching (Germany); Forschungszentrum Dresden-Rossendorf, Dresden (Germany)

2009-12-15

The MLLTRAP at the Maier-Leibnitz-Laboratory (Garching) is a new Penning trap facility designed to combine several novel technologies to decelerate, charge breed, cool, bunch and purify the reaction products and perform high-accuracy nuclear and atomic mass measurements. It is now in the commissioning phase, achieving a mass-resolving power of about 10{sup 5} in the purification trap for stable ions. (orig.)

Tracking Color Shift in Ballpoint Pen Ink Using Photoshop Assisted Spectroscopy: A Nondestructive Technique Developed to Rehouse a Nobel Laureate's Manuscript.

Science.gov (United States)

Wright, Kristi; Herro, Holly

2016-01-01

Many historically and culturally significant documents from the mid-to-late twentieth century were written in ballpoint pen inks, which contain light-sensitive dyes that present problems for collection custodians and paper conservators. The conservation staff at the National Library of Medicine (NLM), National Institutes of Health, conducted a multiphase project on the chemistry and aging of ballpoint pen ink that culminated in the development of a new method to detect aging of ballpoint pen ink while examining a variety of storage environments. NLM staff determined that ballpoint pen ink color shift can be detected noninvasively using image editing software. Instructions are provided on how to detect color shift in digitized materials using a technique developed specifically for this project-Photoshop Assisted Spectroscopy. 1 The study results offer collection custodians storage options for historic documents containing ballpoint pen ink.

Pen Branch fault: Confirmatory drilling results

International Nuclear Information System (INIS)

Stieve, A.; Coruh, C.; Costain, J.K.

1994-01-01

The Confirmatory Drilling Project is the final investigation under the Pen Branch Fault Program initiated to determine the capability of the Pen Branch fault (PBF) to release seismic energy. This investigation focused on a small zone over the fault where previously collected seismic reflection data had indicated the fault deforms the subsurface at 150 msec (with reference to an 80 m reference datum). Eighteen drill holes, 2 to basement and the others to 300 ft, were arranged in a scatter pattern over the fault. To adequately define configuration of the layers deformed by the fault boreholes were spaced over a zone of 800 ft, north to south. The closely spaced data were to confirm or refute the existence of flat lying reflectors observed in seismic reflection data and to enable the authors to identify and correlate lithologic layers with seismic reflection data. Results suggest that deformation by the fault in sediments 300 ft deep ad shallower is subtle. Corroboration of the geologic interpretation with the seismic reflection profile is ongoing but preliminary results indicate that specific reflectors can be assigned to lithologic layers. A large amplitude package of reflections below a flat lying continuous reflection at 40 msec can be correlated with a lithology that corresponds to carbonate sediments in geologic cross-section. Further, data also show that a geologic layer as shallow as 30 ft can be traced on these seismic data over the same subsurface distance where geologic cross-section shows corresponding continuity. The subsurface structure is thus corroborated by both methods at this study site

The effect of cathode surface impurities on gap closure

International Nuclear Information System (INIS)

Hinshelwood, D.D.

1983-01-01

Gap closure due to cathode (or anode) plasma motion is often the principal limitation on the pulse length of intense beam diodes and magnetically insulated transmission lines. Since the plasma expansion velocity is typically on the order of the sound speed, a high atomic number plasma is desirable. In recent experiments performed on a Sandia Nereus accelerator (240kV, 50kA, 3-30kA/cm 2 , 70ns) with a parallel plate diode, the cathode plasma was seen to be composed of both the cathode substrate material and constituents (hydrogen and carbon) of surface contaminants such as pump oils. The plasma expansion velocities, inferred from impedance measurements, were 1.5-2 cm/μs and were the same for carbon, aluminum and stainless steel cathodes. This similarity, combined with the temperature estimates of 2-3eV obtained from spectroscopy, implied that the expansion was due to protons from surface contaminants. Similar results were reported from studies of ablatively driven plasmas. In a continuation of the work, the results of time and spatially resolved spectroscopic studies of plasma formed on aluminum cathodes, yielding measurements of the expansion velocities of different components of the cathode plasma, are presented. We have heated stainless steel cathodes in situ to 700 0 C. The Hα line emission was seen to decrease by more than an order of magnitude (becoming lost in the background) when the cathodes were heated but no change in the impedance behavior was observed. Evidently the heating was insufficient to remove the last monolayer, which should contain more than enough hydrogen to close the gap. Preliminary experiments with gold-plated cathodes (which should be more resistant to chemisorption) yielded similar results. Further measurements of plasma formed on heated cathodes are presented

Synchrotron Investigations of SOFC Cathode Degradation

Energy Technology Data Exchange (ETDEWEB)

Idzerda, Yves

2013-09-30

The atomic variations occurring in cathode/electrolyte interface regions of La{sub 1-x}Sr{sub x}Co{sub y}Fe{sub 1-y}O{sub 3-δ} (LSCF) cathodes and other SOFC related materials have been investigated and characterized using soft X-ray Absorption Spectroscopy (XAS) and diffuse soft X-ray Resonant Scattering (XRS). X-ray Absorption Spectroscopy in the soft X-ray region (soft XAS) is shown to be a sensitive technique to quantify the disruption that occurs and can be used to suggest a concrete mechanism for the degradation. For LSC, LSF, and LSCF films, a significant degradation mechanism is shown to be Sr out-diffusion. By using the XAS spectra of hexavalent Cr in SrCrO4 and trivalent Cr in Cr2O3, the driving factor for Sr segregation was identified to be the oxygen vacancy concentration at the anode and cathode side of of symmetric LSCF/GDC/LSCF heterostructures. This is direct evidence of vacancy induced cation diffusion and is shown to be a significant indicator of cathode/electrolyte interfacial degradation. X-ray absorption spectroscopy is used to identify the occupation of the A-sites and B-sites for LSC, LSF, and LSCF cathodes doped with other transition metals, including doping induced migration of Sr to the anti-site for Sr, a significant cathode degradation indicator. By using spatially resolved valence mapping of Co, a complete picture of the surface electrochemistry can be determined. This is especially important in identifying degradation phenomena where the degradation is spatially localized to the extremities of the electrochemistry and not the average. For samples that have electrochemical parameters that are measured to be spatially uniform, the Co valence modifications were correlated to the effects of current density, overpotential, and humidity.

Reducing DRIFT backgrounds with a submicron aluminized-mylar cathode

Science.gov (United States)

Battat, J. B. R.; Daw, E.; Dorofeev, A.; Ezeribe, A. C.; Fox, J. R.; Gauvreau, J.-L.; Gold, M.; Harmon, L.; Harton, J.; Lafler, R.; Landers, J.; Lauer, R. J.; Lee, E. R.; Loomba, D.; Lumnah, A.; Matthews, J.; Miller, E. H.; Mouton, F.; Murphy, A. St. J.; Paling, S. M.; Phan, N.; Sadler, S. W.; Scarff, A.; Schuckman, F. G.; Snowden-Ifft, D.; Spooner, N. J. C.; Walker, D.

2015-09-01

Background events in the DRIFT-IId dark matter detector, mimicking potential WIMP signals, are predominantly caused by alpha decays on the central cathode in which the alpha particle is completely or partially absorbed by the cathode material. We installed a 0.9 μm thick aluminized-mylar cathode as a way to reduce the probability of producing these backgrounds. We study three generations of cathode (wire, thin-film, and radiologically clean thin-film) with a focus on the ratio of background events to alpha decays. Two independent methods of measuring the absolute alpha decay rate are used to ensure an accurate result, and agree to within 10%. Using alpha range spectroscopy, we measure the radiologically cleanest cathode version to have a contamination of 3.3±0.1 ppt 234U and 73±2 ppb 238U. This cathode reduces the probability of producing an RPR from an alpha decay by a factor of 70±20 compared to the original stainless steel wire cathode. First results are presented from a texturized version of the cathode, intended to be even more transparent to alpha particles. These efforts, along with other background reduction measures, have resulted in a drop in the observed background rate from 500/day to 1/day. With the recent implementation of full-volume fiducialization, these remaining background events are identified, allowing for background-free operation.

Fabrication of a pen-shaped portable biochemical reaction system based on magnetic bead manipulation

International Nuclear Information System (INIS)

Shikida, Mitsuhiro; Inagaki, Noriyuki; Okochi, Mina; Honda, Hiroyuki; Sato, Kazuo

2011-01-01

A pen-shaped platform that is similar to a mechanical pencil is proposed for producing a portable reaction system. A reaction unit, as the key component in the system, was produced by using a heat shrinkable tube. A mechanical pencil supplied by Mitsubishi Pencil Co. Ltd was used as the pen-shaped platform for driving the reaction cylinder. It was actuated using an inchworm motion. We confirmed that the magnetic beads were successfully manipulated in the droplet in the cylinder-shaped reaction units. (technical note)

RF Photoelectric injectors using needle cathodes

International Nuclear Information System (INIS)

Lewellen, J.W.; Brau, C.A.

2003-01-01

Photocathode RF guns, in various configurations, are the injectors of choice for both current and future applications requiring high-brightness electron beams. Many of these applications, such as single-pass free-electron lasers, require beams with high brilliance but not necessarily high charge per bunch. Field-enhanced photoelectric emission has demonstrated electron-beam current density as high as 10 10 A/m 2 , with a quantum efficiency in the UV that approaches 10% at fields on the order of 10 10 V/m. Thus, the use of even a blunt needle holds promise for increasing cathode quantum efficiency without sacrificing robustness. We present an initial study on the use of needle cathodes in photoinjectors to enhance beam brightness while reducing beam charge. Benefits include lower drive-laser power requirements, easier multibunch operation, lower emittance, and lower beam degradation due to charge-dependent effects in the postinjector accelerator. These benefits result from a combination of a smaller cathode emission area, greatly enhanced RF field strength at the cathode, and the charge scaling of detrimental postinjector linac effects, e.g., transverse wakefields and CSR

RF Photoelectric injectors using needle cathodes

Science.gov (United States)

Lewellen, J. W.; Brau, C. A.

2003-07-01

Photocathode RF guns, in various configurations, are the injectors of choice for both current and future applications requiring high-brightness electron beams. Many of these applications, such as single-pass free-electron lasers, require beams with high brilliance but not necessarily high charge per bunch. Field-enhanced photoelectric emission has demonstrated electron-beam current density as high as 10 10 A/m 2, with a quantum efficiency in the UV that approaches 10% at fields on the order of 10 10 V/m. Thus, the use of even a blunt needle holds promise for increasing cathode quantum efficiency without sacrificing robustness. We present an initial study on the use of needle cathodes in photoinjectors to enhance beam brightness while reducing beam charge. Benefits include lower drive-laser power requirements, easier multibunch operation, lower emittance, and lower beam degradation due to charge-dependent effects in the postinjector accelerator. These benefits result from a combination of a smaller cathode emission area, greatly enhanced RF field strength at the cathode, and the charge scaling of detrimental postinjector linac effects, e.g., transverse wakefields and CSR.

Functionally Graded Cathodes for Solid Oxide Fuel Cells

International Nuclear Information System (INIS)

Lei Yang; Ze Liu; Shizhone Wang; Jaewung Lee; Meilin Liu

2008-01-01

The main objective of this DOE project is to demonstrate that the performance and long-term stability of the state-of-the-art LSCF cathode can be enhanced by a catalytically active coating (e.g., LSM or SSC). We have successfully developed a methodology for reliably evaluating the intrinsic surface catalytic properties of cathode materials. One of the key components of the test cell is a dense LSCF film, which will function as the current collector for the electrode material under evaluation to eliminate the effect of ionic and electronic transport. Since it is dense, the effect of geometry would be eliminated as well. From the dependence of the electrode polarization resistance on the thickness of a dense LSCF electrode and on partial pressure of oxygen, we have confirmed that the surface catalytic activity of LSCF limits the performances of LSCF-based cathodes. Further, we have demonstrated, using test cells of different configurations, that the performance of LSCF-based electrodes can be significantly enhanced by infiltration of a thin film of LSM or SSC. In addition, the stability of LSCF-based cathodes was also improved by infiltration of LSM or SSC. While the concept feasibility of the electrode architecture is demonstrated, many details are yet to be determined. For example, it is not clear how the surface morphology, composition, and thickness of the coatings change under operating conditions over time, how these changes influence the electrochemical behavior of the cathodes, and how to control the microscopic details of the coatings in order to optimize the performance. The selection of the catalytic materials as well as the detailed microstructures of the porous LSCF and the catalyst layer may critically impact the performance of the proposed cathodes. Further, other fundamental questions still remain; it is not clear why the degradation rates of LSCF cathodes are relatively high, why a LSM coating improves the stability of LSCF cathodes, which catalysts

Post-Removal Examination of GTF Cathode No.2

International Nuclear Information System (INIS)

Kirby, R.

2005-01-01

This photo-cathode (PC), GTF Cathode No.2, was removed from the GTF in October, 2000. It was characterized in September, 1999 by G. Mulhollan and me (Report entitled ''A Brief Report on a Brief Examination of the Electropolished GTF Cathode'', LCLS-TN-99-10). The cathode conditions and results of that exam were: (1) The cathode was conventionally machined and cleaned in the SLAC Plating Shop. (2) The machining process left a central defect (400 microns diameter) which was not removed by electropolishing. (3) The electropolished surface was ''orange-peeled'', typical of excessive polishing. (4) Secondary electron microscopy (SEM) examination showed numerous 10 micron-diameter etch pits and a small number of copper surface particles. Operation of this cathode in the GTF exhibited ''holloW--beam'' behavior, suggesting that the central defect may have been responsible for non-normal emergence of the photo-emitted beam. No laser cleaning of the cathode was done, so all arc features are due to breakdowns. Post-removal analysis consisted of loW--magnification digital camera pictures (taken with glancing-incidence tungsten white light illumination, to emphasize particles/pitting) and SEM. All images are available in digital (TIFF) form. Also available is a Power Point presentation of the results. Contact me for either. These image files are high-resolution and, thus, large in size. A 200K loW--resolution contact sheet of a few images is attached to this report. Images are referred to by file name

Tailored Core Shell Cathode Powders for Solid Oxide Fuel Cells

Energy Technology Data Exchange (ETDEWEB)

Swartz, Scott [NexTech Materials, Ltd.,Lewis Center, OH (United States)

2015-03-23

In this Phase I SBIR project, a “core-shell” composite cathode approach was evaluated for improving SOFC performance and reducing degradation of lanthanum strontium cobalt ferrite (LSCF) cathode materials, following previous successful demonstrations of infiltration approaches for achieving the same goals. The intent was to establish core-shell cathode powders that enabled high performance to be obtained with “drop-in” process capability for SOFC manufacturing (i.e., rather than adding an infiltration step to the SOFC manufacturing process). Milling, precipitation and hetero-coagulation methods were evaluated for making core-shell composite cathode powders comprised of coarse LSCF “core” particles and nanoscale “shell” particles of lanthanum strontium manganite (LSM) or praseodymium strontium manganite (PSM). Precipitation and hetero-coagulation methods were successful for obtaining the targeted core-shell morphology, although perfect coverage of the LSCF core particles by the LSM and PSM particles was not obtained. Electrochemical characterization of core-shell cathode powders and conventional (baseline) cathode powders was performed via electrochemical impedance spectroscopy (EIS) half-cell measurements and single-cell SOFC testing. Reliable EIS testing methods were established, which enabled comparative area-specific resistance measurements to be obtained. A single-cell SOFC testing approach also was established that enabled cathode resistance to be separated from overall cell resistance, and for cathode degradation to be separated from overall cell degradation. The results of these EIS and SOFC tests conclusively determined that the core-shell cathode powders resulted in significant lowering of performance, compared to the baseline cathodes. Based on the results of this project, it was concluded that the core-shell cathode approach did not warrant further investigation.

Improved Rare-Earth Emitter Hollow Cathode

Science.gov (United States)

Goebel, Dan M.

2011-01-01

An improvement has been made to the design of the hollow cathode geometry that was created for the rare-earth electron emitter described in Compact Rare Earth Emitter Hollow Cathode (NPO-44923), NASA Tech Briefs, Vol. 34, No. 3 (March 2010), p. 52. The original interior assembly was made entirely of graphite in order to be compatible with the LaB6 material, which cannot be touched by metals during operation due to boron diffusion causing embrittlement issues in high-temperature refractory materials. Also, the graphite tube was difficult to machine and was subject to vibration-induced fracturing. This innovation replaces the graphite tube with one made out of refractory metal that is relatively easy to manufacture. The cathode support tube is made of molybdenum or molybdenum-rhenium. This material is easily gun-bored to near the tolerances required, and finish machined with steps at each end that capture the orifice plate and the mounting flange. This provides the manufacturability and robustness needed for flight applications, and eliminates the need for expensive e-beam welding used in prior cathodes. The LaB6 insert is protected from direct contact with the refractory metal tube by thin, graphite sleeves in a cup-arrangement around the ends of the insert. The sleeves, insert, and orifice plate are held in place by a ceramic spacer and tungsten spring inserted inside the tube. To heat the cathode, an insulating tube is slipped around the refractory metal hollow tube, which can be made of high-temperature materials like boron nitride or aluminum nitride. A screw-shaped slot, or series of slots, is machined in the outside of the ceramic tube to constrain a refractory metal wire wound inside the slot that is used as the heater. The screw slot can hold a single heater wire that is then connected to the front of the cathode tube by tack-welding to complete the electrical circuit, or it can be a double slot that takes a bifilar wound heater with both leads coming out

Ultra High Energy Density Cathodes with Carbon Nanotubes

Science.gov (United States)

2013-12-10

a) Carbon nanotube paper coated with NCA cathode composite for testing as positive electrode in Li-ion battery (b) Comparison of NCA specific...received and purified CNT electrodes coated with NCA cathode composite. (b) Discharge capacities as a function of rate and cycle for NCA on Al and...thickness increases. The first approach was to cast SOA NCA cathode composites onto CNT current collectors using an adjustable blade coater. The

Hollow Cathode Studies for the Next Generation Ion Engines in JAXA

Science.gov (United States)

Ohkawa, Yasushi; Hayakawa, Yukio; Yoshida, Hideki; Miyazaki, Katsuhiro; Kitamura, Shoji; Kajiwara, Kenichi

The current status of experimental studies of hollow cathodes for the next-generation ion engines in the Aerospace Research and Development Directorate, JAXA is described. One of the topics on the hollow cathode studies is a life test of a discharge cathode. The keeper disk, orifice plate, and cathode tube of this discharge cathode are made of "high density graphite," which possesses much higher tolerance to ion impingement compared with conventional metal materials. The life test had started in March 2006 and the cumulative operation time reached 15,600 hours in April 2008. No severe degradation has been found both in the operation voltages and electrodes so far, and the test is favorably in progress. In addition to the life test of the discharge cathode, some experiments for design optimization of neutralizer cathodes have been performed. A life test of the neutralizer cathode is being started in June 2008.

Comparison of bacterial culture and qPCR testing of rectal and pen floor samples as diagnostic approaches to detect enterotoxic Escherichia coli in nursery pigs

DEFF Research Database (Denmark)

Weber, N. R.; Nielsen, J. P.; Hjulsager, Charlotte Kristiane

2017-01-01

Enterotoxigenic E. coli (ETEC) are a major cause of diarrhoea in weaned pigs. The objective of this study was to evaluate the agreement at pen level among three different diagnostic approaches for the detection of ETEC in groups of nursery pigs with diarrhoea. The diagnostic approaches used were......: bacterial culturing of faecal samples from three pigs (per pen) with clinical diarrhoea and subsequent testing for virulence genes in E. coli isolates; bacterial culturing of pen floor samples and subsequent testing for virulence genes in E. coli isolates; qPCR testing of pen floor samples in order...... to determine the quantity of F18 and F4 genes. The study was carried out in three Danish pig herds and included 31 pens with a pen-level diarrhoea prevalence of > 25%, as well as samples from 93 diarrhoeic nursery pigs from these pens. All E. coli isolates were analysed by PCR and classified as ETEC when genes...

Performance Enhancement of Small Molecular Solar Cells by Bilayer Cathode Buffer.

Science.gov (United States)

Sun, Qinjun; Zhao, Huanbin; Zhou, Miao; Gao, Liyan; Hao, Yuying

2016-04-01

An effective composite bilayer cathode buffer structure is proposed for use in small molecular solar cells. CsF was doped in Alq3 to form the first cathode buffer, leading to small serial resistances. BCP was used as the second cathode buffer to block the holes to the electrode. The optimized bilayer cathode buffer significantly increased the short circuit and fill factor of devices. By integrating this bilayer cathode buffer, the CuPc/C60 small molecular heterojunction cell exhibited a power conversion efficiency of up to 0.8%, which was an improvement of 56% compared to a device with only the Alq3 cathode buffer. Meanwhile, the bilayer cathode buffer still has a good protective effect on the performance of the device.

Rare earth oxide doping in oxide cathodes

International Nuclear Information System (INIS)

Engelsen, Daniel den; Gaertner, Georg

2006-01-01

The effect on life performance and poisoning with O 2 by doping oxide cathodes with rare earth oxides and pseudo rare earth oxides, notably yttria, is qualitatively explained in terms of electrolysis of BaO during emission of electrons. Doped cathodes show less electrolysis and consume therefore less Ba during life: consequently, doped cathodes have a better life performance. However, the lower Ba-production makes doped cathodes more sensitive to oxygen poisoning. The experimentally found relation between conductivity and yttria concentration was the motive to propose a new model for the crystal imperfections in BaO. In this new imperfection model most Y 3+ -ions will combine with barium vacancies, therefore, the increase of the conductivity is modest and also the effect on the position of the Fermi level is modest. By assuming a combination of bulk and surface conductivity, the agreement between experiment and theory can be improved further

TPC cathode read-out with C-pads

International Nuclear Information System (INIS)

Janik, R.; Pikna, M.; Sitar, B.; Strmen, P.; Szarka, I.

2009-01-01

A Time Projection Chamber with 'C' like shaped cathode pads was built and tested. It offers a low gas gain operation, a good pulse shape and a lightweight construction. The Pad Response Function (PRF), the cathode to anode pulse height ratios and the pad pulse shapes of the C-pad structure were measured and compared with planar cathode structures in two different wire geometries. The cathode to anode signal ratio was improved from between 0.2 and 0.4 up to 0.7. The PRF was considerably improved, it has a Gaussian shape and is narrower than in the case of the planar pads. The pulse shape from the C-pad read-out is similar to the pulse shape from a detector with a cylindrical shape of electrodes. A method for aluminum pad mass production based on a precise cold forging was developed and tested.

Geiger counters of gamma rays with a bismuth cathode

International Nuclear Information System (INIS)

Meunier, R.; Legrand, J.P.

1953-01-01

Geiger Muller counters present a lake of efficiency of some per cent, for the γ radiations. In the region 0,3 - 1 MeV, a substantial growth of their output can be obtained by a special construction of their cathode. In accordance with previous works, we constructed some counter of formed cathode by a pleated copper wire fencing covered of Bi by electrolysis. The successive modifications brought to a cylindrical conventional cathode in sheet metal of copper, that succeeds to this type of cathode, drive to an improvement of the output. (M.B.) [fr

Methanol-Tolerant Cathode Catalyst Composite For Direct Methanol Fuel Cells

Science.gov (United States)

Zhu, Yimin; Zelenay, Piotr

2006-03-21

A direct methanol fuel cell (DMFC) having a methanol fuel supply, oxidant supply, and its membrane electrode assembly (MEA) formed of an anode electrode and a cathode electrode with a membrane therebetween, a methanol oxidation catalyst adjacent the anode electrode and the membrane, an oxidant reduction catalyst adjacent the cathode electrode and the membrane, comprises an oxidant reduction catalyst layer of a platinum-chromium alloy so that oxidation at the cathode of methanol that crosses from the anode through the membrane to the cathode is reduced with a concomitant increase of net electrical potential at the cathode electrode.

Pipelines cathodic protection design methodologies for impressed ...

African Journals Online (AJOL)

Several inadequate designs of cathodically polarized offshore and onshore pipelines have been reported in Nigeria owing to design complexity and application of the cathodic protection system. The present study focused on critical and detailed approach in impressed current and sacrificial anode design calculation ...

Patient evaluation of the use of follitropin alfa in a prefilled ready-to-use injection pen in assisted reproductive technology: an observational study

Directory of Open Access Journals (Sweden)

Welcker J

2010-09-01

Full Text Available Abstract Background Self-administration of recombinant human follicle-stimulating hormone (r-hFSH can be performed using injection pen devices by women undergoing assisted reproductive technology procedures. The objective of this study was to explore the use of the prefilled follitropin alfa pen in routine assisted reproductive technology procedures in Germany. Methods This prospective, observational study was conducted across 43 German IVF centres over a period of 1.75 years. Patients who had used the prefilled follitropin alfa pen in the current or a previous cycle of controlled ovarian stimulation completed a questionnaire to assess their opinions of the device. Results A total of 5328 patients were included in the study. Of these, 2888 reported that they had previous experience of daily FSH injections. Significantly more patients reported that less training was required to use the prefilled follitropin alfa pen than a syringe and lyophilized powder (1997/3081 [64.8%]; p Conclusions In this questionnaire-based survey, routine use of the prefilled follitropin alfa pen was well accepted and associated with favourable patient perceptions. Users of the pen found it easier to initially learn how to use, and subsequently use, than other injection methods. In general, the prefilled follitropin alfa pen was the preferred method for self-administration of gonadotrophins. Together with previous findings, the results here indicate a high level of patient satisfaction among users of the prefilled follitropin alfa pen for daily self-administration of r-hFSH.

Numerical study on rectangular microhollow cathode discharge

International Nuclear Information System (INIS)

He Shoujie; Ouyang Jiting; He Feng; Li Shang

2011-01-01

Rectangular microhollow cathode discharge in argon is investigated by using two-dimensional time-dependent self-consistent fluid model. The electric potential, electric field, particle density, and mean electron energy are calculated. The results show that hollow cathode effect can be onset in the present configuration, with strong electric field and high mean electron energy in the cathode fall while high density and quasineutral plasma in the negative glow. The potential well and electric filed reversal are formed in the negative glow region. It is suggested that the presence of large electron diffusion flux necessitates the field reversal and potential well.

Plasma distribution of cathodic ARC deposition system

International Nuclear Information System (INIS)

Anders, S.; Raoux, S.; Krishnan, K.; MacGill, R.A.; Brown, I.G.

1996-01-01

The plasma distribution using a cathodic arc plasma source with and without magnetic macroparticle filter has been determined by depositing on a transparent plastic substrate and measuring the film absorption. It was found that the width of the distribution depends on the arc current, and it also depends on the cathode material which leads to a spatial separation of the elements when an alloy cathode is used. By applying a magnetic multicusp field near the exit of the magnetic filter, it was possible to modify the plasma distribution and obtain a flat plasma profile with a constant and homogeneous elemental distribution

Cyclotron resonance in a cathode ray tube

International Nuclear Information System (INIS)

Gherbanovschi, N.; Tanasa, M.; Stoican, O.

2002-01-01

Absorption of the RF energy by the electron beam in a cathode ray tube due to the cyclotron resonance is described. The cathode ray tube is placed within a Helmholtz coils system supplied by a sawtooth current generator. In order to generate RF field and to detect RF absorption a gate dip-meter equipped with a FET transistor is used. The bias voltage variations of the FET transistors as a function of the magnetic field are recorded. The operating point of the cathode ray tube has been chosen so that the relaxation oscillations of the detection system can be observed. (authors)

Investigations Of A Pulsed Cathodic Vacuum Arc

Science.gov (United States)

Oates, T. W. H.; Pigott, J.; Denniss, P.; Mckenzie, D. R.; Bilek, M. M. M.

2003-06-01

Cathodic vacuum arcs are well established as a method for producing thin films for coatings and as a source of metal ions. Research into DC vacuum arcs has been going on for over ten years in the School of Physics at the University of Sydney. Recently a project was undertaken in the school to design and build a pulsed CVA for use in the investigation of plasma sheaths and plasma immersion ion implantation. Pulsed cathodic vacuum arcs generally have a higher current and plasma density and also provide a more stable and reproducible plasma density than their DC counterparts. Additionally it has been shown that if a high repetition frequency can be established the deposition rate of pulsed arcs is equal to or greater than that of DC arcs with a concomitant reduction in the rate of macro-particle formation. We present here results of our investigations into the building of a center-triggered pulsed cathodic vacuum arc. The design of the power supply and trigger mechanism and the geometry of the anode and cathode are examined. Observations of type I and II arc spots using a CCD camera, and cathode spot velocity dependence on arc current will be presented. The role of retrograde motion in a high current pulsed arc is discussed.

Investigations Of A Pulsed Cathodic Vacuum Arc

International Nuclear Information System (INIS)

Oates, T.W.H.; Pigott, J.; Denniss, P.; Mckenzie, D.R.; Bilek, M.M.M.

2003-01-01

Cathodic vacuum arcs are well established as a method for producing thin films for coatings and as a source of metal ions. Research into DC vacuum arcs has been going on for over ten years in the School of Physics at the University of Sydney. Recently a project was undertaken in the school to design and build a pulsed CVA for use in the investigation of plasma sheaths and plasma immersion ion implantation. Pulsed cathodic vacuum arcs generally have a higher current and plasma density and also provide a more stable and reproducible plasma density than their DC counterparts. Additionally it has been shown that if a high repetition frequency can be established the deposition rate of pulsed arcs is equal to or greater than that of DC arcs with a concomitant reduction in the rate of macro-particle formation. We present here results of our investigations into the building of a center-triggered pulsed cathodic vacuum arc. The design of the power supply and trigger mechanism and the geometry of the anode and cathode are examined. Observations of type I and II arc spots using a CCD camera, and cathode spot velocity dependence on arc current will be presented. The role of retrograde motion in a high current pulsed arc is discussed

Neutral hydrophilic cathode catalyst binders for microbial fuel cells

KAUST Repository

Saito, Tomonori

2011-01-01

Improving oxygen reduction in microbial fuel cell (MFC) cathodes requires a better understanding of the effects of the catalyst binder chemistry and properties on performance. A series of polystyrene-b-poly(ethylene oxide) (PS-b-PEO) polymers with systematically varying hydrophilicity were designed to determine the effect of the hydrophilic character of the binder on cathode performance. Increasing the hydrophilicity of the PS-b-PEO binders enhanced the electrochemical response of the cathode and MFC power density by ∼15%, compared to the hydrophobic PS-OH binder. Increased cathode performance was likely a result of greater water uptake by the hydrophilic binder, which would increase the accessible surface area for oxygen reduction. Based on these results and due to the high cost of PS-b-PEO, the performance of an inexpensive hydrophilic neutral polymer, poly(bisphenol A-co-epichlorohydrin) (BAEH), was examined in MFCs and compared to a hydrophilic sulfonated binder (Nafion). MFCs with BAEH-based cathodes with two different Pt loadings initially (after 2 cycles) had lower MFC performance (1360 and 630 mW m-2 for 0.5 and 0.05 mg Pt cm-2) than Nafion cathodes (1980 and 1080 mW m -2 for 0.5 and 0.05 mg Pt cm-2). However, after long-term operation (22 cycles, 40 days), power production of each cell was similar (∼1200 and 700-800 mW m-2 for 0.5 and 0.05 mg Pt cm-2) likely due to cathode biofouling that could not be completely reversed through physical cleaning. While binder chemistry could improve initial electrochemical cathode performance, binder materials had less impact on overall long-term MFC performance. This observation suggests that long-term operation of MFCs will require better methods to avoid cathode biofouling. © 2011 The Royal Society of Chemistry.

Review: Factors affecting fouling in conventional pens for slaughter pigs

DEFF Research Database (Denmark)

Larsen, Mona Lilian Vestbjerg; Bertelsen, Maja; Pedersen, Lene Juul

2018-01-01

and pigs’ earlier experience. Further, these primary factors are affected by secondary factors such as the shape of the pen, the weight of the pigs and especially the heat balance of the pigs, which is affected by several tertiary factors including, for example, temperature, humidity and draught. Results...

Dynamics of a single ion in a perturbed Penning trap: Octupolar perturbation

International Nuclear Information System (INIS)

Lara, Martin; Salas, J. Pablo

2004-01-01

Imperfections in the design or implementation of Penning traps may give rise to electrostatic perturbations that introduce nonlinearities in the dynamics. In this paper we investigate, from the point of view of classical mechanics, the dynamics of a single ion trapped in a Penning trap perturbed by an octupolar perturbation. Because of the axial symmetry of the problem, the system has two degrees of freedom. Hence, this model is ideal to be managed by numerical techniques like continuation of families of periodic orbits and Poincare surfaces of section. We find that, through the variation of the two parameters controlling the dynamics, several periodic orbits emanate from two fundamental periodic orbits. This process produces important changes (bifurcations) in the phase space structure leading to chaotic behavior

Barium depletion in hollow cathode emitters

International Nuclear Information System (INIS)

Polk, James E.; Mikellides, Ioannis G.; Katz, Ira; Capece, Angela M.

2016-01-01

Dispenser hollow cathodes rely on a consumable supply of Ba released by BaO-CaO-Al 2 O 3 source material in the pores of a tungsten matrix to maintain a low work function surface. The examination of cathode emitters from long duration tests shows deposits of tungsten at the downstream end that appear to block the flow of Ba from the interior. In addition, a numerical model of Ba transport in the cathode plasma indicates that the Ba partial pressure in the insert may exceed the equilibrium vapor pressure of the dominant Ba-producing reaction, and it was postulated previously that this would suppress Ba loss in the upstream part of the emitter. New measurements of the Ba depletion depth from a cathode insert operated for 8200 h reveal that Ba loss is confined to a narrow region near the downstream end, confirming this hypothesis. The Ba transport model was modified to predict the depletion depth with time. A comparison of the calculated and measured depletion depths gives excellent qualitative agreement, and quantitative agreement was obtained assuming an insert temperature 70 °C lower than measured beginning-of-life values

Air-cathode structure optimization in separator-coupled microbial fuel cells

KAUST Repository

Zhang, Xiaoyuan

2011-12-01

Microbial fuel cells (MFC) with 30% wet-proofed air cathodes have previously been optimized to have 4 diffusion layers (DLs) in order to limit oxygen transfer into the anode chamber and optimize performance. Newer MFC designs that allow close electrode spacing have a separator that can also reduce oxygen transfer into the anode chamber, and there are many types of carbon wet-proofed materials available. Additional analysis of conditions that optimize performance is therefore needed for separator-coupled MFCs in terms of the number of DLs and the percent of wet proofing used for the cathode. The number of DLs on a 50% wet-proofed carbon cloth cathode significantly affected MFC performance, with the maximum power density decreasing from 1427 to 855mW/m 2 for 1-4 DLs. A commonly used cathode (30% wet-proofed, 4 DLs) produced a maximum power density (988mW/m 2) that was 31% less than that produced by the 50% wet-proofed cathode (1 DL). It was shown that the cathode performance with different materials and numbers of DLs was directly related to conditions that increased oxygen transfer. The coulombic efficiency (CE) was more affected by the current density than the oxygen transfer coefficient for the cathode. MFCs with the 50% wet-proofed cathode (2 DLs) had a CE of >84% (6.8A/m 2), which was substantially larger than that previously obtained using carbon cloth air-cathodes lacking separators. These results demonstrate that MFCs constructed with separators should have the minimum number of DLs that prevent water leakage and maximize oxygen transfer to the cathode. © 2011 Elsevier B.V.

Cathode power distribution system and method of using the same for power distribution

Science.gov (United States)

Williamson, Mark A; Wiedmeyer, Stanley G; Koehl, Eugene R; Bailey, James L; Willit, James L; Barnes, Laurel A; Blaskovitz, Robert J

2014-11-11

Embodiments include a cathode power distribution system and/or method of using the same for power distribution. The cathode power distribution system includes a plurality of cathode assemblies. Each cathode assembly of the plurality of cathode assemblies includes a plurality of cathode rods. The system also includes a plurality of bus bars configured to distribute current to each of the plurality of cathode assemblies. The plurality of bus bars include a first bus bar configured to distribute the current to first ends of the plurality of cathode assemblies and a second bus bar configured to distribute the current to second ends of the plurality of cathode assemblies.

Power generation by packed-bed air-cathode microbial fuel cells

KAUST Repository

Zhang, Xiaoyuan

2013-08-01

Catalysts and catalyst binders are significant portions of the cost of microbial fuel cell (MFC) cathodes. Many materials have been tested as aqueous cathodes, but air-cathodes are needed to avoid energy demands for water aeration. Packed-bed air-cathodes were constructed without expensive binders or diffusion layers using four inexpensive carbon-based materials. Cathodes made from activated carbon produced the largest maximum power density of 676±93mW/m2, followed by semi-coke (376±47mW/m2), graphite (122±14mW/m2) and carbon felt (60±43mW/m2). Increasing the mass of activated carbon and semi-coke from 5 to ≥15g significantly reduced power generation because of a reduction in oxygen transfer due to a thicker water layer in the cathode (~3 or ~6cm). These results indicate that a thin packed layer of activated carbon or semi-coke can be used to make inexpensive air-cathodes for MFCs. © 2013 Elsevier Ltd.

Reservoir Cathode for Electric Space Propulsion, Phase II

Data.gov (United States)

National Aeronautics and Space Administration — We propose a hollow reservoir cathode to improve performance in ion and Hall thrusters. We will adapt our existing reservoir cathode technology to this purpose....

Review on pen-and-paper-based observational methods for assessing ergonomic risk factors of computer work.

Science.gov (United States)

Rahman, Mohd Nasrull Abdol; Mohamad, Siti Shafika

2017-01-01

Computer works are associated with Musculoskeletal Disorders (MSDs). There are several methods have been developed to assess computer work risk factor related to MSDs. This review aims to give an overview of current techniques available for pen-and-paper-based observational methods in assessing ergonomic risk factors of computer work. We searched an electronic database for materials from 1992 until 2015. The selected methods were focused on computer work, pen-and-paper observational methods, office risk factors and musculoskeletal disorders. This review was developed to assess the risk factors, reliability and validity of pen-and-paper observational method associated with computer work. Two evaluators independently carried out this review. Seven observational methods used to assess exposure to office risk factor for work-related musculoskeletal disorders were identified. The risk factors involved in current techniques of pen and paper based observational tools were postures, office components, force and repetition. From the seven methods, only five methods had been tested for reliability. They were proven to be reliable and were rated as moderate to good. For the validity testing, from seven methods only four methods were tested and the results are moderate. Many observational tools already exist, but no single tool appears to cover all of the risk factors including working posture, office component, force, repetition and office environment at office workstations and computer work. Although the most important factor in developing tool is proper validation of exposure assessment techniques, the existing observational method did not test reliability and validity. Futhermore, this review could provide the researchers with ways on how to improve the pen-and-paper-based observational method for assessing ergonomic risk factors of computer work.

Explosive emission cathode on the base of carbon plastic fibre

International Nuclear Information System (INIS)

Korenev, S.A.; Baranov, A.M.; Kostyuchenko, S.V.; Chernenko, N.M.

1989-01-01

A fabrication process for explosive emission cathodes on the base of carbon plastic fibre of practically any geometrical shape and dimensions is developed. Experimental studies of electron beam current collection from cathodes, 2cm in diameter, at voltages across the diode of 10 and 150-250kV. It is shown that the ignition voltage for cathode plasma is ∼2kV at the interelectrode diode gap of 5mm and residual gas pressure of ∼5x10 -5 Torr. The carbon-fibre cathode, fabricated in this way, provides more stable current collection of an electron beam (without oscillations) than other cathodes

Tracking Color Shift in Ballpoint Pen Ink Using Photoshop Assisted Spectroscopy: A Nondestructive Technique Developed to Rehouse a Nobel Laureate's Manuscript

OpenAIRE

Wright, Kristi; Herro, Holly

2016-01-01

Many historically and culturally significant documents from the mid-to-late twentieth century were written in ballpoint pen inks, which contain light-sensitive dyes that present problems for collection custodians and paper conservators. The conservation staff at the National Library of Medicine (NLM), National Institutes of Health, conducted a multiphase project on the chemistry and aging of ballpoint pen ink that culminated in the development of a new method to detect aging of ballpoint pen ...

Surface studies of thermionic cathodes and the mechanism of operation of an impregnated tungsten cathode

International Nuclear Information System (INIS)

Forman, R.

1976-09-01

The surface properties of conventional impregnated cathodes were investigated by the use of Auger spectroscopy and work function measurements, and these were compared with a synthesized barium- or barium oxide coated tungsten surface. The barium- and barium oxide coated surfaces were prepared by evaporating barium onto a tungsten surface that can be heated to elevated temperatures. Multilayer or monolayer coverages can be investigated using this technique. The results of this study show that the surface of an impregnated tungsten cathode is identical to that observed for a synthesized monolayer or partial monolayer of barium on partially oxidized tungsten, using the criteria of identical Auger patterns and work functions. Desorption measurements of barium from a tungsten surface were also made. These results in conjunction with Auger and work function data were interpreted to show that throughout most of its life an impregnated cathode operating in the range of 1100 C has a partial monolayer rather than a monolayer of barium on its surface

Nest building and posture changes and activity budget of gilts housed in pens and crates

DEFF Research Database (Denmark)

Andersen, Inger Lise; Vasdal, Guro; Pedersen, Lene Juul

2014-01-01

was born until 8 h after the birth of the first piglet. There was no significant effect of the sows breeding value on any of the sow behaviours. Sows housed in pens spent significantly more time nest building than crated sows from 4 to 12 h prepartum (P ...The aim of the present work was to study nest building, posture changes and the overall activity budget of gilts in pens vs. crates. Twenty-three HB gilts (high piglet survival day 5) and 21 LB gilts (low piglet survival day 5) were video recorded from day 110 in pregnancy to four days after...... farrowing in either a farrowing pen or farrowing crate. The gilts were provided with 2 kg of chopped straw daily from day 113 of pregnancy until farrowing in both environments. Nest building and other activity measures of the sows were analysed using continuous sampling the last 12 h before the first piglet...

Xenon-based Penning mixtures for proportional counters

International Nuclear Information System (INIS)

Ramsey, B.D.; Agrawal, P.C.; National Aeronautics and Space Administration, Huntsville, AL

1989-01-01

The choice of quench gas can have a significant effect on the gas gain and energy resolution of gas-filed proportional counters. Details are given on the performance obtained with a variety of quench additives of varying ionization potentials for use in xenon-filled systems. It is confirmed that optimum performance is obtained when the ionization potential is closely matched to the first metastable level of xenon (8.3 eV) as is the case with xenon + trimethylamine and xenon + dimethylamine. For these mixtures the Penning effect is at its strongest. (orig.)

Mechanism of force mode dip-pen nanolithography

Energy Technology Data Exchange (ETDEWEB)

Yang, Haijun, E-mail: yanghaijun@sinap.ac.cn, E-mail: swguo@sjtu.edu.cn, E-mail: wanghuabin@cigit.ac.cn [Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Research Institute of Micro/Nano Science and Technology, Shanghai Jiao Tong University, Shanghai 200240 (China); Interfacial Water Division and Key Laboratory of Interfacial Physics and Technology, Shanghai Institute of Applied Physics, CAS, Shanghai 201800 (China); Xie, Hui; Rong, Weibin; Sun, Lining [State Key Laboratory of Robotics and Systems, Harbin Institute of Technology, Harbin 150080 (China); Wu, Haixia; Guo, Shouwu, E-mail: yanghaijun@sinap.ac.cn, E-mail: swguo@sjtu.edu.cn, E-mail: wanghuabin@cigit.ac.cn [Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Research Institute of Micro/Nano Science and Technology, Shanghai Jiao Tong University, Shanghai 200240 (China); Wang, Huabin, E-mail: yanghaijun@sinap.ac.cn, E-mail: swguo@sjtu.edu.cn, E-mail: wanghuabin@cigit.ac.cn [Centre for Tetrahertz Research, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714 (China)

2014-05-07

In this work, the underlying mechanism of the force mode dip-pen nanolithography (FMDPN) is investigated in depth by analyzing force curves, tapping mode deflection signals, and “Z-scan” voltage variations during the FMDPN. The operation parameters including the relative “trigger threshold” and “surface delay” parameters are vital to control the loading force and dwell time for ink deposition during FMDPN. A model is also developed to simulate the interactions between the atomic force microscope tip and soft substrate during FMDPN, and verified by its good performance in fitting our experimental data.

Barium depletion study on impregnated cathodes and lifetime prediction

International Nuclear Information System (INIS)

Roquais, J.M.; Poret, F.; Doze, R. le; Ricaud, J.L.; Monterrin, A.; Steinbrunn, A.

2003-01-01

In the thermionic cathodes used in cathode ray-tubes (CRTs), barium is the key element for the electronic emission. In the case of the dispenser cathodes made of a porous tungsten pellet impregnated with Ba, Ca aluminates, the evaporation of Ba determines the cathode lifetime with respect to emission performance in the CRT. The Ba evaporation results in progressive depletion of the impregnating material inside the pellet. In the present work, the Ba depletion with time has been extensively characterized over a large range of cathode temperature. Calculations using the depletion data allowed modeling of the depletion as a function of key parameters. The link between measured depletion and emission in tubes has been established, from which an end-of-life criterion was deduced. Taking modeling into account, predicting accelerated life-tests were performed using high-density maximum emission current (MIK)

New doped tungsten cathodes. Applications to power grid tubes

International Nuclear Information System (INIS)

Cachard, J. de; Cadoret, K; Martinez, L.; Veillet, D.; Millot, F.

2001-01-01

Thermionic emission behavior of tungsten/tungsten carbide modified with rare earth (La, Ce, Y) oxides is examined on account of suitability to deliver important current densities in a thermo-emissive set up and for long lifetime. Work functions of potential cathodes have been determined from Richardson plots for La 2 O 3 doped tungsten and for tungsten covered with variable compositions rare earth tungstates. The role of platinum layers covering the cathode was also examined. Given all cathodes containing mainly lanthanum oxides were good emitters, emphasis was put on service lifetime. Comparisons of lifetime in tungsten doped with rare earth oxides and with rare earth tungstates show that microstructure of the operating cathodes may play the major role in the research of very long lifetime cathodes. Based on these results, tests still running show lifetime compatible with power grid tubes applications. (author)

Testing Iodine as a New Fuel for Cathodes

Science.gov (United States)

Glad, Harley; Branam, Richard; Rogers, Jim; Warren, Matthew; Burleson, Connor; Siy, Grace

2017-11-01

The objective of this research is to demonstrate the viability of using iodine as an alternative space propulsion propellant. The demonstration requires the testing of a cathode with xenon and then the desired element iodine. Currently, cathodes run on noble gases such as xenon which must be stored in high pressure canisters and is very expensive. These shortcomings have led to researching possible substitutes. Iodine was decided as a suitable candidate because it's cheaper, can be stored as a solid, and has similar mass properties as xenon. In this research, cathodes will be placed in a vacuum chamber and operated on both gases to observe their performance, allowing us to gain a better understanding of iodine's behavior. Several planned projects depend on the knowledge gained from this project, such as larger scaled tests and iodine fed hall thrusters. The tasks of this project included protecting the stainless-steel vacuum chamber by gold plating and Teflon® coating, building a stand to hold the cathode, creating an anode resistant to iodine, and testing the cathode once setup was complete. The successful operation of the cathode was demonstrated. However, the experimental setup proved ineffective at controlling the iodine flow. Current efforts are focused on this problem. REU Site: Fluid Mechanics with Analysis using Computations and Experiments NSF Grant EEC 1659710.

Study on the cathode of ion source for neutral beam injector

International Nuclear Information System (INIS)

Tanaka, Shigeru

1983-08-01

Durability of the cathode is an important problem in developing a high power long pulse ion source for neutral beam injector. The Purpose of this study is to develope a long life cathode and investigate the applicability of it to the source. Directly heated filaments which are commonly used as the cathode of injector source do not live very long in general. In the present work, an indirectly heated hollow cathode made of impregnated porous tungsten tube is proposed as the alternative of the directly heated cathode. At first, we fabricated a small hollow cathode to study the discharge characteristcs in a bell-jar configuration and to apply it to a duoPIGatron hydrogen ion source. The experiment showed that the gas flow rate for sustaining the stable arc discharge in the discharge chamber becomes higher than that when the filament cathode is used. To solve this problem, an experiment for gas reduction was made using a newly fabricated larger hollow cathode and a magnetic multi-pole ion source. The influence of the orifice diameter, the effect of a button and of magnetic field on the gas flow rate were experimentally studied and a method for gas reduction was found. In addition, effect of the magnetic field on the characteristics of the hollow cathode ion source was examined in detail and an optimum field configuration around the cathode was found. Finally, beam extraction from an intensively cooled hollow cathode ion source for up to 10 sec was successfully carried out. (author)

Solar 'hot spots' are still hot

Science.gov (United States)

Bai, Taeil

1990-01-01

Longitude distributions of solar flares are not random but show evidence for active zones (or hot spots) where flares are concentrated. According to a previous study, two hot spots in the northern hemisphere, which rotate with a synodic period of about 26.72 days, produced the majority of major flares, during solar cycles 20 and 21. The more prominent of these two hot spots is found to be still active during the rising part of cycle 22, producing the majority of northern hemisphere major flares. The synodic rotation period of this hot spot is 26.727 + or - 0.007 days. There is also evidence for hot spots in the southern hemisphere. Two hot spots separated by 180 deg are found to rotate with a period of 29.407 days, with one of them having persisted in the same locations during cycles 19-22 and the other, during cycles 20-22.

LOW TEMPERATURE CATHODE SUPPORTED ELECTROLYTES

Energy Technology Data Exchange (ETDEWEB)

Harlan U. Anderson; Fatih Dogan; Vladimir Petrovsky

2002-03-31

This project has three main goals: Thin Films Studies, Preparation of Graded Porous Substrates and Basic Electrical Characterization and testing of Planar Single Cells. This period has continued to address the problem of making dense 1/2 to 5 {micro}m thick dense layers on porous substrates (the cathode LSM). Our current status is that we are making structures of 2-5 cm{sup 2} in area, which consist of either dense YSZ or CGO infiltrated into a 2-5 {micro}m thick 50% porous layer made of either nanoncrystalline CGO or YSZ powder. This composite structure coats a macroporous cathode or anode; which serves as the structural element of the bi-layer structure. These structures are being tested as SOFC elements. A number of structures have been evaluated both as symmetrical and as button cell configuration. Results of this testing indicates that the cathodes contribute the most to cell losses for temperatures below 750 C. In this investigation different cathode materials were studied using impedance spectroscopy of symmetric cells and IV characteristics of anode supported fuel cells. Cathode materials studied included La{sub 0.8}Sr{sub 0.2}Co{sub 0.2}Fe{sub 0.8}O{sub 3} (LSCF), La{sub 0.7}Sr{sub 0.2}MnO{sub 3} (LSM), Pr{sub 0.8}Sr{sub 0.2}Fe{sub 0.8}O{sub 3} (PSCF), Sm{sub 0.8}Sr{sub 0.2}Co{sub 0.2}Fe{sub 0.8}O{sub 3} (SSCF), and Yb{sub .8}Sr{sub 0.2}Co{sub 0.2}Fe{sub 0.8}O{sub 3} (SSCF). A new technique for filtering the Fourier transform of impedance data was used to increase the sensitivity of impedance analysis. By creating a filter specifically for impedance spectroscopy the resolution was increased. The filter was tailored to look for specific circuit elements like R//C, Warburg, or constant phase elements. As many as four peaks can be resolved using the filtering technique on symmetric cells. It may be possible to relate the different peaks to material parameters, like the oxygen exchange coefficient. The cathode grouped in order from lowest to highest ASR is

[Effects of large bio-manipulation fish pen on community structure of crustacean zooplankton in Meiliang Bay of Taihu Lake].

Science.gov (United States)

Ke, Zhi-Xin; Xie, Ping; Guo, Long-Gen; Xu, Jun; Zhou, Qiong

2012-08-01

In 2005, a large bio-manipulation pen with the stock of silver carp and bighead carp was built to control the cyanobacterial bloom in Meiliang Bay of Taihu Lake. This paper investigated the seasonal variation of the community structure of crustacean zooplankton and the water quality within and outside the pen. There were no significant differences in the environmental parameters and phytoplankton biomass within and outside the pen. The species composition and seasonal dynamics of crustacean zooplankton within and outside the pen were similar, but the biomass of crustacean zooplankton was greatly suppressed by silver carp and bighead carp. The total crustacean zooplankton biomass and cladocerans biomass were significantly lower in the pen (P < 0.05). In general, silver carp and bighead carp exerted more pressure on cladoceran species than on copepod species. A distinct seasonal succession of crustacean zooplankton was observed in the Bay. Many crustacean species were only dominated in given seasons. Large-sized crustacean (mainly Daphnia sp. and Cyclops vicnus) dominated in winter and spring, while small-sized species (mainly Bosmina sp., Ceriodaphnia cornuta, and Limnoithona sinensis) dominated in summer and autumn. Canonical correspondence analysis showed that water transparency, temperature, and phytoplankton biomass were the most important factors affecting the seasonal succession of the crustacean.

Micro Penning Trap for Continuous Magnetic Field Monitoring in High Radiation Environments

Science.gov (United States)

Latorre, Javiera; Bollen, Georg; Gulyuz, Kerim; Ringle, Ryan; Bado, Philippe; Dugan, Mark; Lebit Team; Translume Collaboration

2016-09-01

As new facilities for rare isotope beams, like FRIB at MSU, are constructed, there is a need for new instrumentation to monitor magnetic fields in beam magnets that can withstand the higher radiation level. Currently NMR probes, the instruments used extensively to monitor magnetic fields, do not have a long lifespans in radiation-high environments. Therefore, a radiation-hard replacement is needed. We propose to use Penning trap mass spectrometry techniques to make high precision magnetic field measurements. Our Penning microtrap will be radiation resistant as all of the vital electronics will be at a safe distance from the radiation. The trap itself is made from materials not subject to radiation damage. Penning trap mass spectrometers can determine the magnetic field by measuring the cyclotron frequency of an ion with a known mass and charge. This principle is used on the Low Energy Beam Ion Trap (LEBIT) minitrap at NSCL which is the foundation for the microtrap. We have partnered with Translume, who specialize in glass micro-fabrication, to develop a microtrap in fused-silica glass. A microtrap is finished and ready for testing at NSCL with all of the electronic and hardware components setup. DOE Phase II SBIR Award No. DE-SC0011313, NSF Award Number 1062410 REU in Physics, NSF under Grant No. PHY-1102511.

Measurements of hot electrons in the Extrap T1 reversed-field pinch

International Nuclear Information System (INIS)

Welander, A.; Bergsaaker, H.

1998-01-01

The presence of an anisotropic energetic electron population in the edge region is a characteristic feature of reversed-field pinch (RFP) plasmas. In the Extrap T1 RFP, the anisotropic, parallel heat flux in the edge region measured by calorimetry was typically several hundred MWm -2 . To gain more insight into the origin of the hot electron component and to achieve time resolution of the hot electron flow during the discharge, a target probe with a soft x-ray monitor was designed, calibrated and implemented. The x-ray emission from the target was measured with a surface barrier detector covered with a set of different x-ray filters to achieve energy resolution. A calibration in the range 0.5-2 keV electron energy was performed on the same target and detector assembly using a LaB 6 cathode electron gun. The calibration data are interpolated and extrapolated numerically. A directional asymmetry of more than a factor of 100 for the higher energy electrons is observed. The hot electrons are estimated to constitute 10% of the total electron density at the edge and their energy distribution is approximated by a half-Maxwellian with a temperature slightly higher than the central electron temperature. Scalings with plasma current, as well as correlations with local Hα measurements and radial dependences, are presented. (author)

A new era for French far right politics?: Comparing the FN under two Le Pens Uma nova era para a extrema-direita francesa?: Uma comparação entre a Frente Nacional dos dois Le Pen

Directory of Open Access Journals (Sweden)

Michelle Hale Williams

2011-10-01

Full Text Available With 2012 elections looming on the horizon in France, much political attention has focused on the new leader of the National Front, Marine Le Pen. She is polling quite well outpacing many of her mainstream party candidate rivals for the 2012 French presidency and the public appears to have embraced her with open arms. Hailed as a promising new face of French politics, a wide swath of the French electorate indicates confidence in her ability to bring needed changes to France. Yet does she really represent a dramatic departure from former FN policies and positions? This article examines the model of the FN during the leadership of Jean-Marie Le Pen in comparison with that seen in the first eight months of Marine Le Pen’s leadership in order to address this question.Com a iminência das eleições francesas de 2012, muita da atenção política se tem centrado na nova líder da Frente Nacional, Marine Le Pen, que tem tido um desempenho notável nas sondagens, ultrapassando muitos dos seus rivais dos partidos tradicionais na corrida para a presidência francesa, e sendo aparentemente acolhida de braços abertos por grande parte do eleitorado. Considerada uma nova e promissora figura no panorama político francês, uma larga fatia do eleitorado demonstra confiança na sua capacidade para trazer ao país a mudança necessária. Mas será que ela representa, de facto, uma ruptura com as antigas posições políticas da FN? O presente artigo examina o modelo da FN sob a liderança de Jean-Marie Le Pen comparando-o com o dos primeiros oito meses da liderança de Marine Le Pen por forma a analisar esta questão.

Numerical study of the generation of runaway electrons in a gas diode with a hot channel

Energy Technology Data Exchange (ETDEWEB)

Lisenkov, V. V., E-mail: lisenkov@iep.uran.ru [Institute of Electrophysics UrB RAS, 106 Amundsena St., Ekaterinburg 620012 (Russian Federation); Ural Federal University, 19 Mira St., Ekaterinburg 620002 (Russian Federation); Shklyaev, V. A., E-mail: shklyaev@to.hcei.tsc.ru [Institute of High Current Electronics SD RAS, 2/3 Akademichesky Avenue, 634055 Tomsk (Russian Federation); National Research Tomsk Polytechnic University, 30 Lenin Avenue, 634050 Tomsk (Russian Federation)

2015-11-15

A new method for increasing the efficiency of runaway electron beam generation in atmospheric pressure gas media has been suggested and theoretically proved. The method consists of creating a hot region (e.g., a spark channel or a laser plume) with a decreased numerical density of gas molecules (N) near the cathode. In this method, the ratio E/N (E—electric field strength) is increased by decreasing N instead of increasing E, as has been done in the past. The numerical model that is used allows the simultaneous calculation of the formation of a subnanosecond gas discharge and the generation of runaway electrons in gas media. The calculations have demonstrated the possibility of obtaining current pulses of runaway electrons with amplitudes of hundred of amperes and durations of more than 100 ps. The influence of the hot channel geometry on the parameters of the generated beam has been investigated.

Polymer coatings as separator layers for microbial fuel cell cathodes

KAUST Repository

Watson, Valerie J.; Saito, Tomonori; Hickner, Michael A.; Logan, Bruce E.

2011-01-01

and increased coulombic efficiency (CE = 56-64%) relative to an uncoated cathode (29 ± 8%), but decreased power production (255-574 mW m-2). Electrochemical characterization of the cathodes ex situ to the MFC showed that the cathodes with the lowest charge

Cathodic Protection Model Facility

Data.gov (United States)

Federal Laboratory Consortium — FUNCTION: Performs Navy design and engineering of ship and submarine impressed current cathodic protection (ICCP) systems for underwater hull corrosion control and...

Application of M-type cathodes to high-power cw klystrons

Science.gov (United States)

Isagawa, S.; Higuchi, T.; Kobayashi, K.; Miyake, S.; Ohya, K.; Yoshida, M.

1999-05-01

Two types of high-power cw klystrons have been widely used at KEK in both TRISTAN and KEKB e +e - collider projects: one is a 0.8 MW/1.0 MW tube, called YK1302/YK1303 (Philips); the other is a 1.2 MW tube, called E3786/E3732 (Toshiba). Normally, the dispenser cathodes of the `B-type' and the `S-type' have been used, respectively, but for improved versions they have been replaced by low-temperature cathodes, called the `M-type'. An Os/Ru coating was applied to the former, whereas an Ir one was applied to the latter. Until now, all upgraded tubes installing M-type cathodes, 9 and 8 in number, respectively, have worked successfully without any dropout. A positive experience concerning the lifetime under real operation conditions has been obtained. M-type cathodes are, however, more easily poisoned. One tube installing an Os/Ru-coated cathode showed a gradual, and then sudden decrease in emission during an underheating test, although the emission could fortunately be recovered by aging at the KEK test field. Once sufficiently aged, the emission of an Ir-coated cathode proved to be very high and stable, and its lifetime is expected to be very long. One disadvantage of this cathode is, however, susceptibility to gas poisoning and the necessity of long-term initial aging. New techniques, like ion milling and fine-grained tungsten top layers, were not as successful as expected from their smaller scale applications to shorten the initial aging period. A burn-in process at higher cathode loading was efficient to make the poisoned cathode active and to decrease unwanted Wehnelt emission. On top of that, the emission cooling, and thus thermal conductivity near the emitting layer could play an important role in such large-current cathodes as ours.

Cathodic behavior of zirconium in aqueous solutions

International Nuclear Information System (INIS)

Hine, F.; Yasuda, M.; Sato, H.

1977-01-01

The electrochemical behavior of Zr was studied by polarization measurements. The surface oxide and zirconium hydride formed by cathodic polarization of Zr have been examined by X-ray, SEM, and a hardness tester. Zirconium hydride would form on Zr cathode after the surface oxide is reduced at the potential, which is several hundred mV more noble than the predicted value shown by the Pourbaix diagram. The parameters for the hydrogen evolution reaction on the hydride formed Zr cathode differs from that on the oxide covered surface, which means that hydrogen evolution takes place on both surfaces under a different mechanism, while details are still veiled at present

Air cathode structure manufacture

Science.gov (United States)

Momyer, William R.; Littauer, Ernest L.

1985-01-01

An improved air cathode structure for use in primary batteries and the like. The cathode structure includes a matrix active layer, a current collector grid on one face of the matrix active layer, and a porous, nonelectrically conductive separator on the opposite face of the matrix active layer, the collector grid and separator being permanently bonded to the matrix active layer. The separator has a preselected porosity providing low IR losses and high resistance to air flow through the matrix active layer to maintain high bubble pressure during operation of the battery. In the illustrated embodiment, the separator was formed of porous polypropylene. A thin hydrophobic film is provided, in the preferred embodiment, on the current collecting metal grid.

The cathode material for a plasma-arc heater

Science.gov (United States)

Yelyutin, A. V.; Berlin, I. K.; Averyanov, V. V.; Kadyshevskii, V. S.; Savchenko, A. A.; Putintseva, R. G.

1983-11-01

The cathode of a plasma arc heater experiences a large thermal load. The temperature of its working surface, which is in contact with the plasma, reaches high values, as a result of which the electrode material is subject to erosion. Refractory metals are usually employed for the cathode material, but because of the severe erosion do not usually have a long working life. The most important electrophysical characteristic of the electrode is the electron work function. The use of materials with a low electron work function allows a decrease in the heat flow to the cathode, and this leads to an increase in its erosion resistance and working life. The electroerosion of certain materials employed for the cathode in an electric arc plasma generator in the process of reduction smelting of refractory metals was studied.

On the actual cathode mixed potential in direct methanol fuel cells

Science.gov (United States)

Zago, M.; Bisello, A.; Baricci, A.; Rabissi, C.; Brightman, E.; Hinds, G.; Casalegno, A.

2016-09-01

Methanol crossover is one of the most critical issues hindering commercialization of direct methanol fuel cells since it leads to waste of fuel and significantly affects cathode potential, forming a so-called mixed potential. Unfortunately, due to the sluggish anode kinetics, it is not possible to obtain a reliable estimation of cathode potential by simply measuring the cell voltage. In this work we address this limitation, quantifying the mixed potential by means of innovative open circuit voltage (OCV) tests with a methanol-hydrogen mixture fed to the anode. Over a wide range of operating conditions, the resulting cathode overpotential is between 250 and 430 mV and is strongly influenced by methanol crossover. We show using combined experimental and modelling analysis of cathode impedance that the methanol oxidation at the cathode mainly follows an electrochemical pathway. Finally, reference electrode measurements at both cathode inlet and outlet provide a local measurement of cathode potential, confirming the reliability of the innovative OCV tests and permitting the evaluation of cathode potential up to typical operating current. At 0.25 A cm-2 the operating cathode potential is around 0.85 V and the Ohmic drop through the catalyst layer is almost 50 mV, which is comparable to that in the membrane.

High-Performance Direct Methanol Fuel Cells with Precious-Metal-Free Cathode.

Science.gov (United States)

Li, Qing; Wang, Tanyuan; Havas, Dana; Zhang, Hanguang; Xu, Ping; Han, Jiantao; Cho, Jaephil; Wu, Gang

2016-11-01

Direct methanol fuel cells (DMFCs) hold great promise for applications ranging from portable power for electronics to transportation. However, apart from the high costs, current Pt-based cathodes in DMFCs suffer significantly from performance loss due to severe methanol crossover from anode to cathode. The migrated methanol in cathodes tends to contaminate Pt active sites through yielding a mixed potential region resulting from oxygen reduction reaction and methanol oxidation reaction. Therefore, highly methanol-tolerant cathodes must be developed before DMFC technologies become viable. The newly developed reduced graphene oxide (rGO)-based Fe-N-C cathode exhibits high methanol tolerance and exceeds the performance of current Pt cathodes, as evidenced by both rotating disk electrode and DMFC tests. While the morphology of 2D rGO is largely preserved, the resulting Fe-N-rGO catalyst provides a more unique porous structure. DMFC tests with various methanol concentrations are systematically studied using the best performing Fe-N-rGO catalyst. At feed concentrations greater than 2.0 m, the obtained DMFC performance from the Fe-N-rGO cathode is found to start exceeding that of a Pt/C cathode. This work will open a new avenue to use nonprecious metal cathode for advanced DMFC technologies with increased performance and at significantly reduced cost.

Solar hot spots are still hot

International Nuclear Information System (INIS)

Bai, T.

1990-01-01

Longitude distributions of solar flares are not random but show evidence for active zones (or hot spots) where flares are concentrated. According to a previous study, two hot spots in the northern hemisphere, which rotate with a synodic period of about 26.72 days, produced the majority of major flares, during solar cycles 20 and 21. The more prominent of these two hot spots is found to be still active during the rising part of cycle 22, producing the majority of northern hemisphere major flares. The synodic rotation period of this hot spot is 26.727 + or - 0.007 days. There is also evidence for hot spots in the southern hemisphere. Two hot spots separated by 180 deg are found to rotate with a period of 29.407 days, with one of them having persisted in the same locations during cycles 19-22 and the other, during cycles 20-22. 14 refs

Effects of cathodic protection on cracking of high-strength pipeline steels

Energy Technology Data Exchange (ETDEWEB)

Elboujdaini, M.; Revie, R. W.; Attard, M. [CANMET Materials Technology Laboratory, Ottawa, ON(Canada)], email: melboujd@nrcan.gc.ca

2010-07-01

Four strength levels of pipeline steels, ranging from X-70 to X-120, were compared to determine whether higher strength materials are more susceptible to hydrogen embrittlement under cathodic protection. Ductility was measured in a solution at four protection levels, going from no cathodic protection to 500 mV of overprotection. All four steels showed loss of ductility under cathodic protection. Under cathodic polarization, the loss of ductility increased with the strength of the steel and the activity of the potential. After slow-strain-rate experiments conducted in air and examination of fracture surfaces, it is concluded that application of cathodic potentials, cathodic overprotection, higher strength of steel, and exposure to aqueous solution are factors that decrease the ductility of steel. Hydrogen reduction seems to be an important factor in ductility reduction and fractures. Observations suggest that high-strength pipelines need better control of cathodic protection than lower-strength pipelines.

Plasma-induced field emission and plasma expansion of carbon nanotube cathodes

International Nuclear Information System (INIS)

Liao Qingliang; Zhang Yue; Qi Junjie; Huang Yunhua; Xia Liansheng; Gao Zhanjun; Gu Yousong

2007-01-01

High intensity electron emission cathodes based on carbon nanotube films have been successfully fabricated. An investigation of the explosive field emission properties of the carbon nanotube cathode in a double-pulse mode was presented and a high emission current density of 245 A cm -2 was obtained. The formation of the cathode plasma layer was proved and the production process of the electron beams from the cathode was explained. The time and space resolution of the electron beams flow from the cathode was investigated. The plasma expanded at a velocity of ∼8.17 cm μs -1 towards the anode and influenced on the intensity and distribution of electron beams obviously. The formation of cathode plasma had no preferential position and the local enhancement of electron beams was random. This carbon nanotube cathode appears to be suitable for high-power microwave device applications

High-Current Cold Cathode Employing Diamond and Related Materials

Energy Technology Data Exchange (ETDEWEB)

Hirshfield, Jay L. [Omega-P, Inc., New Haven, CT (United States)

2014-10-22

The essence of this project was for diamond films to be deposited on cold cathodes to improve their emission properties. Films with varying morphology, composition, and size of the crystals were deposited and the emission properties of the cathodes that utilize such films were studied. The prototype cathodes fabricated by the methods developed during Phase I were tested and evaluated in an actual high-power RF device during Phase II. These high-power tests used the novel active RF pulse compression system and the X-band magnicon test facility at US Naval Research Laboratory. In earlier tests, plasma switches were employed, while tests under this project utilized electron-beam switching. The intense electron beams required in the switches were supplied from cold cathodes embodying diamond films with varying morphology, including uncoated molybdenum cathodes in the preliminary tests. Tests with uncoated molybdenum cathodes produced compressed X-band RF pulses with a peak power of 91 MW, and a maximum power gain of 16.5:1. Tests were also carried out with switches employing diamond coated cathodes. The pulse compressor was based on use of switches employing electron beam triggering to effect mode conversion. In experimental tests, the compressor produced 165 MW in a ~ 20 ns pulse at ~18× power gain and ~ 140 MW at ~ 16× power gain in a 16 ns pulse with a ~ 7 ns flat-top. In these tests, molybdenum blade cathodes with thin diamond coatings demonstrated good reproducible emission uniformity with a 100 kV, 100 ns high voltage pulse. The new compressor does not have the limitations of earlier types of active pulse compressors and can operate at significantly higher electric fields without breakdown.

Particle-in-cell simulations of anomalous transport in a Penning discharge

Science.gov (United States)

Carlsson, Johan; Kaganovich, Igor; Powis, Andrew; Raitses, Yevgeny; Romadanov, Ivan; Smolyakov, Andrei

2018-06-01

Electrostatic particle-in-cell simulations of a Penning discharge are performed in order to investigate azimuthally asymmetric, spoke-like structures previously observed in experiments. Two-dimensional simulations show that for Penning-discharge conditions, a persistent nonlinear spoke-like structure forms readily and rotates in the direction of E × B and electron diamagnetic drifts. The azimuthal velocity is within about a factor of 2 of the ion acoustic speed. The spoke frequency follows the experimentally observed scaling with ion mass, which indicates the importance of ion inertia in spoke formation. The spoke provides enhanced (anomalous) radial electron transport, and the effective cross-field conductivity is several times larger than the classical (collisional) value. The level of anomalous current obtained in the simulations is in good agreement with the experimental data. The rotating spoke channels most of the radial current, observable by an edge probe as short pulses.

Penning traps with unitary architecture for storage of highly charged ions.

Science.gov (United States)

Tan, Joseph N; Brewer, Samuel M; Guise, Nicholas D

2012-02-01

Penning traps are made extremely compact by embedding rare-earth permanent magnets in the electrode structure. Axially-oriented NdFeB magnets are used in unitary architectures that couple the electric and magnetic components into an integrated structure. We have constructed a two-magnet Penning trap with radial access to enable the use of laser or atomic beams, as well as the collection of light. An experimental apparatus equipped with ion optics is installed at the NIST electron beam ion trap (EBIT) facility, constrained to fit within 1 meter at the end of a horizontal beamline for transporting highly charged ions. Highly charged ions of neon and argon, extracted with initial energies up to 4000 eV per unit charge, are captured and stored to study the confinement properties of a one-magnet trap and a two-magnet trap. Design considerations and some test results are discussed.

Penning traps with unitary architecture for storage of highly charged ions

International Nuclear Information System (INIS)

Tan, Joseph N.; Guise, Nicholas D.; Brewer, Samuel M.

2012-01-01

Penning traps are made extremely compact by embedding rare-earth permanent magnets in the electrode structure. Axially-oriented NdFeB magnets are used in unitary architectures that couple the electric and magnetic components into an integrated structure. We have constructed a two-magnet Penning trap with radial access to enable the use of laser or atomic beams, as well as the collection of light. An experimental apparatus equipped with ion optics is installed at the NIST electron beam ion trap (EBIT) facility, constrained to fit within 1 meter at the end of a horizontal beamline for transporting highly charged ions. Highly charged ions of neon and argon, extracted with initial energies up to 4000 eV per unit charge, are captured and stored to study the confinement properties of a one-magnet trap and a two-magnet trap. Design considerations and some test results are discussed.

Fundamental Investigations and Rational Design of Durable High-Performance SOFC Cathodes

Energy Technology Data Exchange (ETDEWEB)

Chen, Yu [Georgia Inst. of Technology, Atlanta, GA (United States); Ding, Dong [Georgia Inst. of Technology, Atlanta, GA (United States); Wei, Tao [Georgia Inst. of Technology, Atlanta, GA (United States); Liu, Meilin [Georgia Inst. of Technology, Atlanta, GA (United States)

2016-03-31

The main objective of this project is to unravel the degradation mechanism of LSCF cathodes under realistic operating conditions with different types of contaminants, aiming towards the rational design of cathodes with high-performance and enhanced durability by combining a porous backbone (such as LSCF) with a thin catalyst coating. The mechanistic understanding will help us to optimize the composition and morphology of the catalyst layer and microstructure of the LSCF backbone for better performance and durability. More specifically, the technical objectives include: (1) to unravel the degradation mechanism of LSCF cathodes under realistic operating conditions with different types of contaminants using in situ and ex situ measurements performed on specially-designed cathodes; (2) to examine the microstructural and compositional evolution of LSCF cathodes as well as the cathode/electrolyte interfaces under realistic operating conditions; (3) to correlate the fuel cell performance instability and degradation with the microstructural and morphological evolution and surface chemistry change of the cathode under realistic operating conditions; (4) to explore new catalyst materials and electrode structures to enhance the stability of the LSCF cathode under realistic operating conditions; and (5) to validate the long term stability of the modified LSCF cathode in commercially available cells under realistic operating conditions. We have systematically evaluated LSCF cathodes in symmetrical cells and anode supported cells under realistic conditions with different types of contaminants such as humidity, CO₂, and Cr. Electrochemical models for the design of test cells and understanding of mechanisms have been developed for the exploration of fundamental properties of electrode materials. It is demonstrated that the activity and stability of LSCF cathodes can be degraded by the introduction of contaminants. The microstructural and compositional evolution of LSCF

SOFC LSM:YSZ cathode degradation induced by moisture: An impedance spectroscopy study

DEFF Research Database (Denmark)

Nielsen, Jimmi; Mogensen, Mogens Bjerg

2011-01-01

The cause of the degradation effect of moisture during operation of LSM cathode based SOFCs has been investigated by means of a detailed impedance characterization on LSM:YSZ composite cathode based SOFCs. Further the role of YSZ as cathode composite material was studied by measurements on SOFCs...... with a LSM:CGO composite cathode on a CGO interdiffusion barrier layer. It was found that both types of cathodes showed similar electrochemical characteristics towards the presence of moisture during operation. Upon addition and removal of moisture in the fed air the impedance study showed a change...... in the high frequency cathode arc, which is associated with the charge transport/transfer at the LSM/YSZ interface. On prolonged operation with the presence of moisture an ongoing increase in the high frequency cathode arc resulted in a permanent loss of cathode/electrolyte contact and thus increase...

Characteristics of Handwriting of People With Cerebellar Ataxia: Three-Dimensional Movement Analysis of the Pen Tip, Finger, and Wrist.

Science.gov (United States)

Fujisawa, Yuhki; Okajima, Yasutomo

2015-11-01

There are several functional tests for evaluating manual performance; however, quantitative manual tests for ataxia, especially those for evaluating handwriting, are limited. This study aimed to investigate the characteristics of cerebellar ataxia by analyzing handwriting, with a special emphasis on correlation between the movement of the pen tip and the movement of the finger or wrist. This was an observational study. Eleven people who were right-handed and had cerebellar ataxia and 17 people to serve as controls were recruited. The Scale for the Assessment and Rating of Ataxia was used to grade the severity of ataxia. Handwriting movements of both hands were analyzed. The time required for writing a character, the variability of individual handwriting, and the correlation between the movement of the pen tip and the movement of the finger or wrist were evaluated for participants with ataxia and control participants. The writing time was longer and the velocity profile and shape of the track of movement of the pen tip were more variable in participants with ataxia than in control participants. For participants with ataxia, the direction of movement of the pen tip deviated more from that of the finger or wrist, and the shape of the track of movement of the pen tip differed more from that of the finger or wrist. The severity of upper extremity ataxia measured with the Scale for the Assessment and Rating of Ataxia was mostly correlated with the variability parameters. Furthermore, it was correlated with the directional deviation of the trajectory of movement of the pen tip from that of the finger and with increased dissimilarity of the shapes of the tracks. The results may have been influenced by the scale and parameters used to measure movement. Ataxic handwriting with increased movement noise is characterized by irregular pen tip movements unconstrained by the finger or wrist. The severity of ataxia is correlated with these unconstrained movements. © 2015 American

Novel methods for improvement of a Penning ion source for neutron generator applications.

Science.gov (United States)

Sy, A; Ji, Q; Persaud, A; Waldmann, O; Schenkel, T

2012-02-01

Penning ion source performance for neutron generator applications is characterized by the atomic ion fraction and beam current density, providing two paths by which source performance can be improved for increased neutron yields. We have fabricated a Penning ion source to investigate novel methods for improving source performance, including optimization of wall materials and electrode geometry, advanced magnetic confinement, and integration of field emitter arrays for electron injection. Effects of several electrode geometries on discharge characteristics and extracted ion current were studied. Additional magnetic confinement resulted in a factor of two increase in beam current density. First results indicate unchanged proton fraction and increased beam current density due to electron injection from carbon nanofiber arrays.

Discrimination of Black Ball-point Pen Inks by High Performance Liquid Chromatography (HPLC)

International Nuclear Information System (INIS)

Mohamed Izzharif Abdul Halim; Norashikin Saim; Rozita Osman; Halila Jasmani; Nurul Nadhirah Zainal Abidin

2013-01-01

In this study, thirteen types of black ball-point pen inks of three major brands were analyzed using high performance liquid chromatography (HPLC). Separation of the ink components was achieved using Bondapak C-18 column with gradient elution using water, ethanol and ethyl acetate. The chromatographic data obtained at wavelength 254.8 nm was analyzed using agglomerative hierarchical clustering (AHC) and principle component analysis (PCA). AHC was able to group the inks into three clusters. This result was supported by PCA, whereby distinct separation of the three different brands was achieved. Therefore, HPLC in combination with chemometric methods may be a valuable tool for the analysis of black ball-point pen inks for forensic purposes. (author)

Application of micro-attenuated total reflectance Fourier transform infrared spectroscopy to ink examination in signatures written with ballpoint pen on questioned documents.

Science.gov (United States)

Nam, Yun Sik; Park, Jin Sook; Lee, Yeonhee; Lee, Kang-Bong

2014-05-01

Questioned documents examined in a forensic laboratory sometimes contain signatures written with ballpoint pen inks; these signatures were examined to assess the feasibility of micro-attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopy as a forensic tool. Micro-ATR FTIR spectra for signatures written with 63 ballpoint pens available commercially in Korea were obtained and used to construct an FTIR spectral database. A library-searching program was utilized to identify the manufacturer, blend, and model of each black ballpoint pen ink based upon their FTIR peak intensities, positions, and patterns in the spectral database. This FTIR technique was also successfully used in determining the sequence of homogeneous line intersections from the crossing lines of two ballpoint pen signatures. We have demonstrated with a set of sample documents that micro-ATR FTIR is a viable nondestructive analytical method that can be used to identify the origin of the ballpoint pen ink used to mark signatures. © 2014 American Academy of Forensic Sciences.

The early behaviour of cow and calf in an individual calving pen

DEFF Research Database (Denmark)

Jensen, Margit Bak

2011-01-01

The aim was to investigate the early behaviour in dairy cows and their calves. Thirty-eight multiparous Danish Holstein Frisian cows and their calves were housed in individual calving pens during the first twelve days post-partum and their behaviour was observed during 24 h on days 3, 7 and 11....... Cows gradually reduced the time spent sniffing and licking their calves from 59 to 49 min over the days studied (P cow from less than half a minute on days 3 and 7 to 1 min on day 11 (P ... studied (P cows’ behavioural priorities, the cows were tested on either day 4, 8 or 12 after calving by removing them from their pens during 3 h and subsequently reintroducing them. Behavioural observations during 3 h after reintroduction showed...

Particle-In-Cell simulations of the Ball-pen probe

Czech Academy of Sciences Publication Activity Database

Komm, M.; Adámek, Jiří; Pekárek, Z.; Pánek, Radomír

2010-01-01

Roč. 50, č. 9 (2010), s. 814-818 ISSN 0863-1042 R&D Projects: GA AV ČR KJB100430901 Institutional research plan: CEZ:AV0Z20430508 Keywords : Ball- pen * tokamak * plasma * plasma potential * PIC * simulation * I-V characteristics Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.006, year: 2010 http://onlinelibrary.wiley.com/doi/10.1002/ctpp.201010137/pdf

Chromium poisoning of LSM/YSZ and LSCF/CGO composite cathodes

DEFF Research Database (Denmark)

Bentzen, Janet Jonna; Høgh, Jens Valdemar Thorvald; Barfod, Rasmus

2009-01-01

from 300 to 2,970 h. Both LSM/YSZ and LSCF/CGO cathodes were sensitive to chromium poisoning; LSCF/CGO cathodes to a lesser extent than LSM/YSZ. Humid air aggravated the degradation of the cathode performance. Post-mortem electron microscopic investigations revealed several Cr-containing compounds...

HOT 2015

DEFF Research Database (Denmark)

Hannibal, Sara Stefansen

2016-01-01

HOT samler og formidler 21 literacykyndiges bud på, hvad der er hot, og hvad der bør være hot inden for literacy – og deres begrundelser for disse bud.......HOT samler og formidler 21 literacykyndiges bud på, hvad der er hot, og hvad der bør være hot inden for literacy – og deres begrundelser for disse bud....

Surface Modification Technique of Cathode Materials for LI-ION Battery

Science.gov (United States)

Jia, Yongzhong; Han, Jinduo; Jing, Yan; Jin, Shan; Qi, Taiyuan

Cathode materials for Li-ion battery LiMn2O4 and LiCo0.1Mn1.9O4 were prepared by soft chemical method. Carbon, which was made by decomposing organic compounds, was used as modifying agent. Cathode material matrix was mixed with water solution that had contained organic compound such as cane sugar, soluble amylum, levulose et al. These mixture were reacted at 150 200 °C for 0.5 4 h in a Teflon-lined autoclave to get a series of homogeneously C-coated cathode materials. The new products were analyzed by X-ray diffraction (XRD) and infrared (IR). Morphology of cathode materials was characterized by scanning electron microscope (SEM) and transition electron microscope (TEM). The new homogeneously C-coated products that were used as cathode materials of lithium-ion battery had good electrochemical stability and cycle performance. This technique has free-pollution, low cost, simpleness and easiness to realize the industrialization of the cathode materials for Li-ion battery.

Orobanche flava Mart. ex F.W. Schultz (Orobanchaceae: en la Península Ibérica

Directory of Open Access Journals (Sweden)

Pujadas Salvá, Antonio J.

2003-12-01

Full Text Available Orobanche flava is reported in the N of the Iberian Península. Its diversity and distribution is analyzed for the península: var. flava in the Pyrenees and var. albicans Rhiner in the Cantabrian Mountain chain. Lectotypification of O. flava var. albicans Rhiner [ZT] is proposed. To facilítate the identification of O. flava we emphasize its differential morphological characters and an original icon is contributed.Se indica la presencia de Orobanche flava en el N de la Península Ibérica. Se analiza su diversidad y su distribución en el territorio: var. flava en el Pirineo y var. albicans Rhiner en la Cordillera Cantábrica. Se propone el lectótipo de O. flava var. albicans Rhiner [ZT]. Para facilitar la identificación de O. flava destacamos sus caracteres morfológicos diferenciales y aportamos un icono original.

Carcass traits and meat quality of growing rabbits in pens with and without different multilevel platforms

Directory of Open Access Journals (Sweden)

M. Martino

2016-06-01

Full Text Available The aim of this trial was to determine the effect of the presence of wire or plastic mesh elevated platforms on carcass traits and meat quality characteristics, with particular attention to the oxidative status of growing rabbits. A total of 174 five-week old rabbits were randomly divided into 3 groups with 2 replications (6 pens; 29 rabbits/pen: pens without platforms (NoP with a stocking density of 16 rabbits/m2 and pens with wire-mesh platforms (WP or plastic-mesh platforms (PP that were placed on 2 levels, with a stocking density of 16 rabbits/m2 on the floor or 9.14 rabbits/m2 when the platform were included. At 84 d rabbits were slaughtered. The slaughter traits and Longissimus lumborum (LL physical and chemical compositition were not affected by treatments. Rabbits from the PP group showed the highest retinol and γ-tocotrienol content on LL muscle, whereas the NoP ones showed a higher α-tocotrienol and α-tocopherol level. The absence of platforms led to decreased (P<0.001 thiobarbituric acid-reactive substances values and induced an improvement in n-3 polyunsaturated fatty acids. Levels of linoleic, linolenic and docosahexaenoic acids were equal to those of the WP group (23.45, 3.75, 0.64% in NoP and 22.6, 4.14, 0.53% in WP, respectively but higher than in PP rabbits (20.86, 3.05, 0.45%, respectively. It can be concluded that the pens with elevated platforms provide greater possibilities for movement, which is beneficial from the viewpoint of animal welfare. However, this greater activity influences the oxidative status of the meat, decreasing the antioxidant content and worsening the lipid oxidation of rabbit meat.

Oxide cathodes produced by plasma deposition

International Nuclear Information System (INIS)

Scheitrum, G.; Caryotakis, G.; Pi, T.; Umstattd, R.; Brown, I.; Montiero, O.

1997-01-01

These are two distinct applications for high-current-density, long-life thermionic cathodes. The first application is as a substitute for explosive emission cathodes used in high-power microwave (HPM) devices being developed for Air Force programs. The second application is in SLAC's X-band klystrons for the Next Linear Collider (NLC). SLAC, UCD, and LBL are developing a plasma deposition process that eliminates the problems with binders, carbonate reduction, peeling, and porosity. The emission layer is deposited using plasma deposition of metallic barium in vacuum with an oxygen background gas. An applied bias voltage drives the oxide plasma into the nickel surface. Since the oxide is deposited directly, it does not have problems with poisoning from a hydrocarbon binder. The density of the oxide layer is increased from the 40--50% for standard oxide cathodes to nearly 100% for plasma deposition

Self-organization in cathode boundary layer discharges in xenon

International Nuclear Information System (INIS)

Takano, Nobuhiko; Schoenbach, Karl H

2006-01-01

Self-organization of direct current xenon microdischarges in cathode boundary layer configuration has been studied for pressures in the range 30-140 Torr and for currents in the range 50 μA-1 mA. Side-on and end-on observations of the discharge have provided information on the structure and spatial arrangement of the plasma filaments. The regularly spaced filaments, which appear in the normal glow mode when the current is lowered, have a length which is determined by the cathode fall. It varies, dependent on pressure and current, between 50 and 70 μm. The minimum diameter is approximately 80 μm, as determined from the radiative emission in the visible. The filaments are sources of extensive excimer emission. Measurements of the cathode fall length have allowed us to determine the secondary emission coefficient for the discharge in the normal glow mode and to estimate the cathode fall voltage at the transition from normal glow mode to filamentary mode. It was found that the cathode fall voltage at this transition decreases, indicating the onset of additional electron gain processes at the cathode. The regular arrangement of the filaments, self-organization, is assumed to be due to Coulomb interactions between the positively charged cathode fall channels and positive space charges on the surface of the surrounding dielectric spacer. Calculations based on these assumptions showed good agreement with experimentally observed filament patterns

An adjustable electron achromat for cathode lens microscopy

Energy Technology Data Exchange (ETDEWEB)

Tromp, R.M., E-mail: rtromp@us.ibm.com [IBM T.J. Watson Research Center, 1101 Kitchawan Road, Yorktown Heights, NY 10598 (United States); Leiden Institute of Physics, Kamerlingh Onnes Laboratory, Niels Bohrweg 2, 2333 CA Leiden (Netherlands)

2015-12-15

Chromatic aberration correction in light optics began with the invention of a two-color-corrected achromatic crown/flint lens doublet by Chester Moore Hall in 1730. Such color correction is necessary because any single glass shows dispersion (i.e. its index of refraction changes with wavelength), which can be counteracted by combining different glasses with different dispersions. In cathode lens microscopes (such as Photo Electron Emission Microscopy – PEEM) we encounter a similar situation, where the chromatic aberration coefficient of the cathode lens shows strong dispersion, i.e. depends (non-linearly) on the energy with which the electrons leave the sample. Here I show how a cathode lens in combination with an electron mirror can be configured as an adjustable electron achromat. The lens/mirror combination can be corrected at two electron energies by balancing the settings of the electron mirror against the settings of the cathode lens. The achromat can be adjusted to deliver optimum performance, depending on the requirements of a specific experiment. Going beyond the achromat, an apochromat would improve resolution and transmission by a very significant margin. I discuss the requirements and outlook for such a system, which for now remains a wish waiting for fulfilment. - Highlights: • The properties of cathode objective lens plus electron mirror are discussed. • In analogy with light-optical achromats, cathode lens plus mirror can be configured as an electron achromat. • Unlike light optics, the electron achromat can be adjusted to best fulfill experimental requirements.

Determination of electric field strength and kinetic temperature in the cathode fall region of a hollow cathode discharge

Energy Technology Data Exchange (ETDEWEB)

De la Rosa, M I; Perez, C; Gruetzmacher, K [Universidad de Valladolid, Facultad de Ciencias, 47071 Valladolid (Spain); Gonzalo, A B; Del Val, J A, E-mail: delarosa@opt.uva.e [Universidad de Salamanca, Escuela Politecnica Superior, 05003 Avila (Spain)

2010-05-01

In this work, we demonstrate the high potential of two-photon excitation of the 1S -2S transition of atomic hydrogen followed by optogalvanic detection, for measuring under identical experimental conditions, the kinetic temperature and the electric field strength in the cathode sheath region of a hollow cathode discharge. The first obtained results for both parameters are discussed in this paper.

The design of cathode for organic photovoltaic devices

Science.gov (United States)

Song, De; Shi, Feng; Xia, Xuan; Li, Ye; Duanmu, Qingduo

2016-11-01

We have discussed the effect of the residual gas in the Al metal cathode deposition process and consequently influence the performance of organic photovoltaic devices (such as organic photoelectron detector or solar cell). We believe that the origin of degradation in Jsc and FF from the Al cathode device should be the formation of AlOx in the C60-Al interface, which contaminate the interface and plays a role like an energy barrier that block the charge collect process. To solve this problem the Ag and Alq3 layer had been inserted before the Al. Owing to the advantageous of Alq3 and Ag layer, the device which Al cathode prepared at a lower vacuum condition exhibits a comparable performance to that device which Al cathode deposited in regular situation. As an additional benefit, since the introducing of Alq3/Ag layer in the VOPc/C60 organic photovoltaic device performs a better near-infrared response, this phenomenon has been confirmed by means of both simulation and experimental data. So the design of our new cathode structure provides a degree of freedom to modulate the light absorption for organic photovoltaic devices in short-wave and long-wave.

High-Current Plasma Electron Sources

International Nuclear Information System (INIS)

Gushenets, J.Z.; Krokhmal, V.A.; Krasik, Ya. E.; Felsteiner, J.; Gushenets, V.

2002-01-01

In this report we present the design, electrical schemes and preliminary results of a test of 4 different electron plasma cathodes operating under Kg h-voltage pulses in a vacuum diode. The first plasma cathode consists of 6 azimuthally symmetrically distributed arc guns and a hollow anode having an output window covered by a metal grid. Plasma formation is initiated by a surface discharge over a ceramic washer placed between a W-made cathode and an intermediate electrode. Further plasma expansion leads to a redistribution of the discharge between the W-cathode and the hollow anode. An accelerating pulse applied between the output anode grid and the collector extracts electrons from this plasma. The operation of another plasma cathode design is based on Penning discharge for preliminary plasma formation. The main glow discharge occurs between an intermediate electrode of the Penning gun and the hollow anode. To keep the background pressure in the accelerating gap at P S 2.5x10 4 Torr either differential pumping or a pulsed gas puff valve were used. The operation of the latter electron plasma source is based on a hollow cathode discharge. To achieve a sharp pressure gradient between the cathode cavity and the accelerating gap a pulsed gas puff valve was used. A specially designed ferroelectric plasma cathode initiated plasma formation inside the hollow cathode. This type of the hollow cathode discharge ignition allowed to achieve a discharge current of 1.2 kA at a background pressure of 2x10 4 Torr. All these cathodes were developed and initially tested inside a planar diode with a background pressure S 2x10 4 Torr under the same conditions: accelerating voltage 180 - 300 kV, pulse duration 200 - 400 ns, electron beam current - 1 - 1.5 kA, and cross-sectional area of the extracted electron beam 113 cm 2

Space and time dependent properties of the virtual cathode in a reflex-type pulsed ion diode (virtual cathode in a reflex-type pulsed ion diode)

International Nuclear Information System (INIS)

Matsumoto, Yoshio; Yano, Syukuro

1982-01-01

Properties of a virtual cathode in a pulsed ion diode composed of an insulator-mesh anode and a metal-mesh cathode were studied experimentally at anode voltages below 360kV. Potential distribution in the virtual cathode side was measured with an insulated electrostatic potential probe, and ion beam currents in virtual and real cathode sides were measured with biased ion collectors. A loss parameter for the electron current at the virtual cathode was evaluated from the measured electron current values by using relations derived from the one-dimensional Child-Langmuir theory applied to the reflex triode. The ion beam accompanies a considerable amount of electron current, and this influences the stability of the virtual cathode; this perturbation results in variations of ion current with time. Space potentials in the emitted ion beam are given, suggesting an existence of high energy electrons of several keV accelerated by positive space potential of the ion beam. (author)

Defining the Pen Islands Caribou Herd of southern Hudson Bay

Directory of Open Access Journals (Sweden)

Kenneth F. Abraham

1998-03-01

Full Text Available In this paper, we describe the Pen Islands Herd of caribou, the largest aggregation of caribou in Ontario (it also occupies a portion of northeastern Manitoba. Photographic counts showed the herd had a minimum population of 2300 in 1979, 4660 in 1986, 7424 in 1987 and 10 798 in 1994. Throughout the 1980s, the Pen Islands caribou exhibited population behaviour similar to migratory barren-ground caribou herds, although morphology suggests they are woodland caribou or possibly a mixture of subspecies. The herd had well-defined traditional tundra calving grounds, formed nursery groups and large mobile post-calving aggregations, and migrated over 400 km between tundra summer habitats and boreal forest winter habitats. Its migration took it into three Canadian jurisdictions (Ontario, Manitoba, Northwest Territories and it was important to residents of both Manitoba and Ontario. It is clear that the herd should be managed as a migratory herd and the critical importance of both the coastal and variable large winter ranges should be noted in ensuring the herd's habitat needs are secure.

Iron phosphate materials as cathodes for lithium batteries

CERN Document Server

Prosini, Pier Paolo

2011-01-01

""Iron Phosphate Materials as Cathodes for Lithium Batteries"" describes the synthesis and the chemical-physical characteristics of iron phosphates, and presents methods of making LiFePO4 a suitable cathode material for lithium-ion batteries. The author studies carbon's ability to increase conductivity and to decrease material grain size, as well as investigating the electrochemical behaviour of the materials obtained. ""Iron Phosphate Materials as Cathodes for Lithium Batteries"" also proposes a model to explain lithium insertion/extraction in LiFePO4 and to predict voltage profiles at variou

Impressed current cathodic protection of deep water structures

Digital Repository Service at National Institute of Oceanography (India)

Venkatesan, R.

that the cathodic protection design approaches for shallow water may not be adequate for deeper water. This paper discusses on environmental factors encountered in deep water and their effect on cathodic protection behaviour of steel. Further, current CP design...

Analytical study of electron flows with a virtual cathode

International Nuclear Information System (INIS)

Dubinov, A.E.

2000-01-01

The dynamics of the electron flow behavior by its injection into a half-space is considered. Two problems are considered, namely the long-term injection of a monoenergetic electron flow and instantaneous flow injection with an assigned electron energy spectrum. The all flow electrons in both cases return to the injection plane. The simple analytical self-consistent model of the initial stage of the virtual cathode formation in a plane-parallel equipotential gap is plotted in the course of analysis whereof the duration of the virtual cathode formation process is determined. The performance of this model is not limited by the multivalence of the electron velocity in the flow. This makes it possible to extend the frames of the model performance relative to the moment of the virtual cathode formation and to consider its dynamics. The frequency of electron oscillations in the potential cathode-virtual cathode well is determined on the basis of the above model [ru

The explosive cathode on the base of carbon-fibrous plastic material

International Nuclear Information System (INIS)

Korenev, S.A.; Baranov, A.M.; Kostyuchenko, S.V.; Chernenko, N.M.

1988-01-01

Production process of exploseve cathodes on the base of carbon-fibrous plastic material of any geometric form and size is discussed. Experimental study of current take-off from cathodes with diameter 2 cm of 10 kV and 150-250 kV voltage are given. It is shown that ignition voltage of cathode plasma is 2 kV with 5 mm gap electrode of diode and 5 ·10 -5 Tor pressure of residual gas. It is shown that carbon-fibrous cathode, made by this technology, provides more stable current take-off electron beam (withoud oscillations) in comparison with other cathodes

Dose measurement in periapical radiographic exams using dosemeter pen: a look at the radioprotection

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Renato; Ferreira, Vanessa, E-mail: vanessamachado@ufmg.br [Curso Superior de Tecnologia em Radiologia. Faculdade de Medicina. Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Pereira, Claubia; Oliveira, Arno H.; Veloso, M.A.F., E-mail: gbarros@nuclear.ufmg.br, E-mail: claubia@nuclear.ufmg.br, E-mail: heeren@nuclear.ufmg.br, E-mail: Dora@nuclear.ufmg.br [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Nuclear

2011-07-01

The use of radiology has been a large increase with the crescent accessibility to dental care, orthodontics and aesthetic. Besides the increase in the number of exams, there was an increase in radiation dose during dental exams such as computed tomography. The objective of this work is to evaluate the radiation dose to which the patient is subjected in a peri apical dental radiography. The dose values were measured with a dosimeter pen during radiographs in real exams peri apical with the X-ray equipment Timex 70 C Gnatus. During the exams realization, was maintained, in the holder, the dosimeter pen near to the region of interest. The values collected were recorded in dosimeter pen. These values were compared with the reference doses of the Portaria 453 of ANVISA, this procedure allows to verify if the recommended dose limits for this exam are being respected. These data indicates if the used equipment is calibrated and in good condition of use. It was performed a comparison between the obtained experimental dose values and the values found from computer simulation with the code MCNPX 2.6.0. (author)

Dose measurement in periapical radiographic exams using dosemeter pen: a look at the radioprotection

International Nuclear Information System (INIS)

Oliveira, Renato; Ferreira, Vanessa; Pereira, Claubia; Oliveira, Arno H.; Veloso, M.A.F.

2011-01-01

The use of radiology has been a large increase with the crescent accessibility to dental care, orthodontics and aesthetic. Besides the increase in the number of exams, there was an increase in radiation dose during dental exams such as computed tomography. The objective of this work is to evaluate the radiation dose to which the patient is subjected in a peri apical dental radiography. The dose values were measured with a dosimeter pen during radiographs in real exams peri apical with the X-ray equipment Timex 70 C Gnatus. During the exams realization, was maintained, in the holder, the dosimeter pen near to the region of interest. The values collected were recorded in dosimeter pen. These values were compared with the reference doses of the Portaria 453 of ANVISA, this procedure allows to verify if the recommended dose limits for this exam are being respected. These data indicates if the used equipment is calibrated and in good condition of use. It was performed a comparison between the obtained experimental dose values and the values found from computer simulation with the code MCNPX 2.6.0. (author)

Development of cathode material for lithium-ion batteries

Directory of Open Access Journals (Sweden)

Rustam Mukhtaruly Turganaly

2014-08-01

Full Text Available The electrochemical characteristics of the cathode material coated with carbon layer has been developed. Various carbon coating methods. There  has been carried out a comparative electrochemical analysis of the coated and uncoated with carbon cathode material. 

HotRegion: a database of predicted hot spot clusters.

Science.gov (United States)

Cukuroglu, Engin; Gursoy, Attila; Keskin, Ozlem

2012-01-01

Hot spots are energetically important residues at protein interfaces and they are not randomly distributed across the interface but rather clustered. These clustered hot spots form hot regions. Hot regions are important for the stability of protein complexes, as well as providing specificity to binding sites. We propose a database called HotRegion, which provides the hot region information of the interfaces by using predicted hot spot residues, and structural properties of these interface residues such as pair potentials of interface residues, accessible surface area (ASA) and relative ASA values of interface residues of both monomer and complex forms of proteins. Also, the 3D visualization of the interface and interactions among hot spot residues are provided. HotRegion is accessible at http://prism.ccbb.ku.edu.tr/hotregion.

Space-time-dependent development of the plasma in a pulsed hollow-cathode discharge

International Nuclear Information System (INIS)

Schaefer, G.; Wages, M.

1988-01-01

This paper presents streak camera investigations on the space-time-dependent development of pulsed hollow-cathode discharges (HCD's) starting from low-current preionization discharges. The discharges started closer to the end of the cathode, then moved further into the cathode, and then spread over a longer range along the axis of the cathode. The depth range of the intense pulsed hollow-cathode plasma was found to be two to eight times the cathode diameter

Virtual cathode regime in nonstationary electric high-current discharge in hydrogen

International Nuclear Information System (INIS)

Baksht, F.G.; Borodin, V.S.; Zhuravlev, V.N.

1988-01-01

Virtual cathode (VC) regime in a non-stationary high-current hydrogen arch is constructed. Basic calculational characteristics of the near-the-cathode layer are presented. The calculation was conducted for a 1 cm long cathode under 2x10 4 A/cm 2 current density in pulse and 10 atm. pressure. A rectangular current pulse was considered. It is shown that VC formation is caused by electron temperature reduction in the near-the-cathode area. This results in the reduction of ion flux from plasma to the cathode surface and finally in the change of a sign of space charge and field intensity near the surface. Under the transition to VC regime only the cathode temperature and its effective work function are practically changed, while the rest of parameters remain approximately constant

Electricity generation of microbial fuel cell with waterproof breathable membrane cathode

Science.gov (United States)

Xing, Defeng; Tang, Yu; Mei, Xiaoxue; Liu, Bingfeng

2015-12-01

Simplification of fabrication and reduction of capital cost are important for scale-up and application of microbial electrochemical systems (MES). A fast and inexpensive method of making cathode was developed via assembling stainless steel mesh (SSM) with waterproof breathable membrane (WBM). Three assemble types of cathodes were fabricated; Pt@SSM/WBM (SSM as cathode skeleton, WBM as diffusion layer, platinum (Pt) catalyst applied on SSM), SSM/Pt@WBM and Pt@WBM. SSM/Pt@WBM cathode showed relatively preferable with long-term stability and favorable power output (24.7 W/m3). Compared to conventional cathode fabrication, air-cathode was made for 0.5 h. The results indicated that the novel fabrication method could remarkably reduce capital cost and simplify fabrication procedures with a comparable power output, making MFC more prospective for future application.

Pre-acclimation of a wastewater inoculum to cellulose in an aqueous–cathode MEC improves power generation in air–cathode MFCs

KAUST Repository

Cheng, Shaoan; Kiely, Patrick; Logan, Bruce E.

2011-01-01

-cathode MFCs with this inoculum produced maximum power densities of 1070mWm-2 (cathode surface area) in single-chamber and 880mWm-2 in two-chamber MFCs. Coulombic efficiencies ranged from 25% to 50%, and COD removals were 50-70% based on total cellulose

Thermal Characteristics of Conversion-Type FeOF Cathode in Li-ion Batteries

Directory of Open Access Journals (Sweden)

Liwei Zhao

2017-10-01

Full Text Available Rutile FeOF was used as a conversion-type cathode material for Li-ion batteries. In the present study, 0.6Li, 1.4Li, and 2.7Li per mole lithiation reactions were carried out by changing the electrochemical discharge reaction depth. The thermal characteristics of the FeOF cathode were investigated by thermogravimetric mass spectrometric (TG-MS and differential scanning calorimeter (DSC systems. No remarkable HF release was detected, even up to 700 °C, which indicated a low toxic risk for the FeOF cathode. Changes in the thermal properties of the FeOF cathode via different conversion reaction depths in the associated electrolyte were studied by changing the cathode/electrolyte ratio in the mixture. LiFeOF was found to exothermically react with the electrolyte at about 210 °C. Similar exothermic reactions were found with charged FeOF cathodes because of the irreversible Li ions. Among the products of the conversion reaction of FeOF, Li2O was found to exothermically react with the electrolyte at about 120 °C, which induced the main thermal risk of the FeOF cathode. It suggests that the oxygen-containing conversion-type cathodes have a higher thermal risk than the oxygen-free ones, but controlling the cathode/electrolyte ratio in cells successfully reduced the thermal risk. Finally, the thermal stability of the FeOF cathode was evaluated in comparison with FeF3 and LiFePO4 cathodes.

Separation of Electrolytic Reduction Product from Stainless Steel Wire Mesh Cathode Basket via Salt Draining and Reuse of the Cathode Basket

OpenAIRE

Choi, Eun-Young; Lee, Jeong; Heo, Dong Hyun; Hur, Jin-Mok

2017-01-01

We demonstrated that the metallic product obtained after electrolytic reduction (also called oxide reduction (OR)) can be simply separated from a stainless steel wire mesh cathode basket only by using a salt drain. First, the OR run of a simulated oxide fuel (0.6 kg/batch) was conducted in a molten Li2O–LiCl salt electrolyte at 650°C. The simulated oxide fuel of the porous cylindrical pellets was used as a cathode by loading a stainless steel wire mesh cathode basket. Platinum was employed as...

Plasma generation using the hollow cathod

International Nuclear Information System (INIS)

Moon, K.J.

1983-01-01

A hollow cathode of tungsten was adapted to an University of California, Berkely, LBL bucket ion source to investigate ion density fluctuations at the extractior grid. Fluctuations in plasma ion density are observed to range between 100kHz to 2 MHz. The observed fluctuation frequencies of plasma ion density are found to be inversely proportional to the square root of ion masses. It is guessed that the plasma fluctuation are also correlated with the hollow cathode length. (Author)

Wire winding increases lifetime of oxide coated cathodes

Science.gov (United States)

Kerslake, W.; Vargo, D.

1965-01-01

Refractory-metal heater base wound with a thin refractory metal wire increases the longevity of oxide-coated cathodes. The wire-wound unit is impregnated with the required thickness of metal oxide. This cathode is useful in magnetohydrodynamic systems and in electron tubes.

Resistivity network and structural model of the oxide cathode for CRT application

OpenAIRE

Hashim, A. A.; Barratt, D. S.; Hassan, A. K.; Evans-Freeman, J. H.; Nabok, A.

2006-01-01

In this paper, the electrical properties of oxide cathode\\ud and oxide cathode plus, supplied by LG Philips Displays, have been\\ud investigated in relation to different cathode activation regimes and\\ud methods. Oxide cathode activation treatment for different durations\\ud has been investigated. The formations of the compounds associated\\ud to the diffusion of reducing elements (Mg, Al, and W) to the Ni cap surface of oxide cathode were studied by a new suggestion method. Scanning electron mi...

Lithium secondary batteries: Role of polymer cathode morphology

Science.gov (United States)

Naoi, Katsuhiko; Osaka, Tetsuya; Owens, Boone B.

1988-06-01

Electrically conducting polymers have been utilized both as the cathode and as the electrolyte element of Li secondary cells. Polymer cathodes were limited in their suitability for batteries because of the low energy content associated with low levels of doping and the inclusion of complex ionic species in the cathode. Recent studies have indicated that doping levels up to 100 percent can be achieved in polyanilene. High doping levels in combination with controlled morphologies have been found to improve the energy and rate capabilities of polymer cathodes. A morphology-modifying technique was utilized to enhance the charge/discharge characteristics of Li/liquid electrolyte polypyrrole cells. The polymer is electropolymerized in a preferred orientation morphology when the substrate is first precoated with an insulating film of nitrile butadiene rubber (NBR). Modification of the kinetic behavior of the electrode results from variations in the chemical composition of the NBR.

Comprehension of handwriting development: Pen-grip kinetics in handwriting tasks and its relation to fine motor skills among school-age children.

Science.gov (United States)

Lin, Yu-Chen; Chao, Yen-Li; Wu, Shyi-Kuen; Lin, Ho-Hsio; Hsu, Chieh-Hsiang; Hsu, Hsiao-Man; Kuo, Li-Chieh

2017-10-01

Numerous tools have been developed to evaluate handwriting performances by analysing written products. However, few studies have directly investigated kinetic performances of digits when holding a pen. This study thus attempts to investigate pen-grip kinetics during writing tasks of school-age children and explore the relationship between the kinetic factors and fine motor skills. This study recruited 181 children aged from 5 to 12 years old and investigated the effects of age on handwriting kinetics and the relationship between these and fine motor skills. The forces applied from the digits and pen-tip were measured during writing tasks via a force acquisition pen, and the children's fine motor performances were also evaluated. The results indicate that peak force and average force might not be direct indicators of handwriting performance for normally developing children at this age. Younger children showed larger force variation and lower adjustment frequency during writing, which might indicate they had poorer force control than the older children. Force control when handling a pen is significantly correlated with fine motor performance, especially in relation to the manual dexterity. A novel system is proposed for analysing school-age children's force control while handwriting. We observed the development of force control in relation to pen grip among the children with different ages in this study. The findings suggested that manipulation skill may be crucial when children are establishing their handwriting capabilities. © 2017 Occupational Therapy Australia.

Photon enhanced thermionic emission

Science.gov (United States)

Schwede, Jared; Melosh, Nicholas; Shen, Zhixun

2014-10-07

Photon Enhanced Thermionic Emission (PETE) is exploited to provide improved efficiency for radiant energy conversion. A hot (greater than 200.degree. C.) semiconductor cathode is illuminated such that it emits electrons. Because the cathode is hot, significantly more electrons are emitted than would be emitted from a room temperature (or colder) cathode under the same illumination conditions. As a result of this increased electron emission, the energy conversion efficiency can be significantly increased relative to a conventional photovoltaic device. In PETE, the cathode electrons can be (and typically are) thermalized with respect to the cathode. As a result, PETE does not rely on emission of non-thermalized electrons, and is significantly easier to implement than hot-carrier emission approaches.

Influence of the radial spacing between cathodes on the surface composition of iron samples sintered by hollow cathode electric discharge

Directory of Open Access Journals (Sweden)

Brunatto S.F.

2001-01-01

Full Text Available The present work reports an investigation of the influence of the radial spacing between cathodes on the iron sintering process by hollow cathode electrical discharge, with surface enrichment of the alloying elements Cr and Ni. Pressed cylindrical samples of 9.5 mm diameter and density of 7.0 ± 0.1 g/cm³ were prepared by compaction of Ancorsteel 1000C iron powder. These samples, constituting the central cathode, were positioned concentrically in the interior of an external cathode machined from a tube of stainless steel AISI 310 (containing: 25% Cr, 16% Ni, 1.5% Mn, 1.5% Si, 0.03% C and the remainder Fe. Sintering was done at 1150 °C, for 120 min, utilizing radial spacings between the central and hollow cathodes of 3, 6 and 9 mm and a gas mixture of 80% Ar and 20% H2, with a flow rate of 5 cm³/s at a pressure of 3 Torr. The electric discharge was generated using a pulsed voltage power source, with a period of 200 mus. The radial spacing had only a slight influence on the quantity of atoms of alloying elements deposited and diffused on the surface of the sample. Analysis with a microprobe showed the presence of chrome (up to 4.0% and nickel (up to 3.0%, in at. % at the surface of the samples. This surface enrichment can be attributed to the mechanism of sputtering of the metallic atoms present in the external cathode, with the deposition of these elements on the sample surface and consequent diffusion within the sample.

Mathematical micro-model of a solid oxide fuel cell composite cathode

International Nuclear Information System (INIS)

Kenney, B.; Karan, K.

2004-01-01

In a solid oxide fuel cell (SOFC), the cathode processes account for a majority of the overall electrochemical losses. A composite cathode comprising a mixture of ion-conducting electrolyte and electron-conducting electro-catalyst can help minimize cathode losses provided microstructural parameters such as particle-size, composition, and porosity are optimized. The cost of composite cathode research can be greatly reduced by incorporating mathematical models into the development cycle. Incorporated with reliable experimental data, it is possible to conduct a parametric study using a model and the predicted results can be used as guides for component design. Many electrode models treat the cathode process simplistically by considering only the charge-transfer reaction for low overpotentials or the gas-diffusion at high overpotentials. Further, in these models an average property of the cathode internal microstructure is assumed. This paper will outline the development of a 1-dimensional SOFC composite cathode micro-model and the experimental procedures for obtaining accurate parameter estimates. The micro-model considers the details of the cathode microstructure such as porosity, composition and particle-size of the ionic and electronic phases, and their interrelationship to the charge-transfer reaction and mass transport processes. The micro-model will be validated against experimental data to determine its usefulness for performance prediction. (author)

Characterization of scandia doped pressed cathode fabricated by spray drying method

International Nuclear Information System (INIS)

Cui Yuntao; Wang Jinshu; Liu Wei; Wang Yiman; Zhou Meiling

2011-01-01

Scandia doped pressed cathode was prepared by a new method of spray drying combined with two-step hydrogen reduction process. The Sc 2 O 3 and barium-calcium aluminate co-doped powders have sub-micrometer size in the range of 0.1-1 μm and scandium oxide and barium-calcium aluminate are distributed evenly in the powders. The cathodes sintered by powder metallurgy at 1600 deg. C b have a smooth surface and sub-micrometer grain structure with homogeneous distribution of scandium, barium, calcium and aluminum which are dispersed over and among the tungsten grains. This cathode has good emission, e.g., the current density of this cathode reaches 31.50 A/cm 2 at 850 deg. C b . After proper activation, the cathode surface is covered by a Ba-Sc-O active substances layer with a preferable atomic ratio, leading to its good emission property. The evaporation activation energy of SDP cathode with 4.58 eV is the highest among the Ba-W, M-type and SDP cathodes, and the average evaporation velocity v t of SDP cathode with 1.28 x 10 -8 g cm -2 s -1 at 1150 deg. C b is the lowest one.

Back bombardment for dispenser and lanthanum hexaboride cathodes

Directory of Open Access Journals (Sweden)

Mahmoud Bakr

2011-06-01

Full Text Available The back bombardment (BB effect limits wide usage of thermionic rf guns. The BB effect induces not only ramping-up of a cathode’s temperature and beam current, but also degradation of cavity voltage and beam energy during a macropulse. This paper presents a comparison of the BB effect for the case of dispenser tungsten-base (DC and lanthanum hexaboride (LaB_{6} thermionic rf gun cathodes. For each, particle simulation codes are used to simulate the BB effect and electron beam dynamics in a thermionic rf gun cathode. A semiempirical equation is also used to investigate the stopping range and deposited heat power of BB electrons in the cathode material. A numerical simulation method is used to calculate the change of the cathode temperature and current density during a single macropulse. This is done by solving two differential equations for the rf gun cavity equivalent circuit and one-dimensional thermal diffusion equation. High electron emission and small beam size are required for generation of a high-brightness electron beam, and so in this work the emission properties of the cathode are taken into account. Simulations of the BB effect show that, for a pulse of 6  μs duration, the DC cathode experiences a large change in the temperature compared with LaB_{6}, and a change in current density 6 times higher. Validation of the simulation results is performed using experimental data for beam current beyond the gun exit. The experimental data is well reproduced using the simulation method.

Development of multi-pixel x-ray source using oxide-coated cathodes.

Science.gov (United States)

Kandlakunta, Praneeth; Pham, Richard; Khan, Rao; Zhang, Tiezhi

2017-07-07

Multiple pixel x-ray sources facilitate new designs of imaging modalities that may result in faster imaging speed, improved image quality, and more compact geometry. We are developing a high-brightness multiple-pixel thermionic emission x-ray (MPTEX) source based on oxide-coated cathodes. Oxide cathodes have high emission efficiency and, thereby, produce high emission current density at low temperature when compared to traditional tungsten filaments. Indirectly heated micro-rectangular oxide cathodes were developed using carbonates, which were converted to semiconductor oxides of barium, strontium, and calcium after activation. Each cathode produces a focal spot on an elongated fixed anode. The x-ray beam ON and OFF control is performed by source-switching electronics, which supplies bias voltage to the cathode emitters. In this paper, we report the initial performance of the oxide-coated cathodes and the MPTEX source.

An explosive-emitter cathode produced using the heavy ion track technique

International Nuclear Information System (INIS)

Akap'ev, G.N.; Korenev, S.A.

1988-01-01

A cathode based on thin metallic foils with a homogeneous needle surface is described. The cathode was manufactured using the heavy ion track technique which permits the production of cathodes with an unlimited area and a needle density ranging from about 10 3 to 10 9 needles per cm 2 . An electron gun using this type of cathode has a current of 200-900 A and an energy of 100-300 keV. The cross section of the electron beam is fairly uniform. It is shown that needle emitters of similar shape and size play the principal role in forming a homogeneous cathode plasma

Formation of virtual cathodes and microwave generation in relativistic electron beams

International Nuclear Information System (INIS)

Kwan, T.J.T.; Thode, L.E.

1984-01-01

Simulation of the generation of a relativistic electron beam in a foil diode configuration and the subsequent intense microwave generation resulting from the formation of the virtual cathode is presented. The oscillating virtual cathode and the trapped beam electrons between the real and the virtual cathodes were found to generate microwaves at two distinct frequencies. Generation of high-power microwaves with about 10% efficiency might reasonably be expected from such a virtual-cathode configuration

Lipon coatings for high voltage and high temperature Li-ion battery cathodes

Energy Technology Data Exchange (ETDEWEB)

Dudney, Nancy J.; Liang, Chengdu; Nanda, Jagjit; Veith, Gabriel M.; Kim, Yoongu; Martha, Surendra Kumar

2017-12-05

A lithium ion battery includes an anode and a cathode. The cathode includes a lithium, manganese, nickel, and oxygen containing compound. An electrolyte is disposed between the anode and the cathode. A protective layer is deposited between the cathode and the electrolyte. The protective layer includes pure lithium phosphorus oxynitride and variations that include metal dopants such as Fe, Ti, Ni, V, Cr, Cu, and Co. A method for making a cathode and a method for operating a battery are also disclosed.

Mosaic-shaped cathode for highly durable solid oxide fuel cell under thermal stress

Science.gov (United States)

Joo, Jong Hoon; Jeong, Jaewon; Kim, Se Young; Yoo, Chung-Yul; Jung, Doh Won; Park, Hee Jung; Kwak, Chan; Yu, Ji Haeng

2014-02-01

In this study, we propose a novel "mosaic structure" for a SOFC (solid oxide fuel cell) cathode with high thermal expansion to improve the stability against thermal stress. Self-organizing mosaic-shaped cathode has been successfully achieved by controlling the amount of binder in the dip-coating solution. The anode-supported cell with mosaic-shaped cathode shows itself to be highly durable performance for rapid thermal cycles, however, the performance of the cell with a non-mosaic cathode exhibits severe deterioration originated from the delamination at the cathode/electrolyte interface after 7 thermal cycles. The thermal stability of an SOFC cathode can be evidently improved by controlling the surface morphology. In view of the importance of the thermal expansion properties of the cathode, the effects of cathode morphology on the thermal stress stability are discussed.

Modular cathode assemblies and methods of using the same for electrochemical reduction

Science.gov (United States)

Wiedmeyer, Stanley G.; Barnes, Laurel A.; Williamson, Mark A.; Willit, James L.

2018-03-20

Modular cathode assemblies are useable in electrolytic reduction systems and include a basket through which fluid electrolyte may pass and exchange charge with a material to be reduced in the basket. The basket can be divided into upper and lower sections to provide entry for the material. Example embodiment cathode assemblies may have any shape to permit modular placement at any position in reduction systems. Modular cathode assemblies include a cathode plate in the basket, to which unique and opposite electrical power may be supplied. Example embodiment modular cathode assemblies may have standardized electrical connectors. Modular cathode assemblies may be supported by a top plate of an electrolytic reduction system. Electrolytic oxide reduction systems are operated by positioning modular cathode and anode assemblies at desired positions, placing a material in the basket, and charging the modular assemblies to reduce the metal oxide.

Coating for lithium anode, thionyl chloride active cathode electrochemical cell

Energy Technology Data Exchange (ETDEWEB)

Catanzarite, V.O.

1983-01-04

Electrochemical power cells having a cathode current collector, a combination liquid active cathode depolarizer electrolyte solvent and an anode that forms surface compounds when in intimate contact with the liquid cathode are enhanced by the addition of a passivation limiting film contiguous to said anode. The passivating film is a member of the cyanoacrilate family of organic compounds.

Coating for lithium anode, thionyl chloride active cathode electrochemical cell

Energy Technology Data Exchange (ETDEWEB)

Catanzarite, V.O.

1981-10-20

Electrochemical power cells having a cathode current collector, a combination liquid active cathode depolarizer electrolyte solvent and an anode that forms surface compounds when in intimate contact with the liquid cathode are enhanced by the addition of a passivation limiting film contiguous to said anode. The passivating film is a member of the cyanoacrilate family of organic compounds.

Development of the Pirani and penning vacuum gauges

International Nuclear Information System (INIS)

Oh, B. H.; In, S. R.; Yoon, B. J.; Yoon, J. S.

2000-02-01

The Pirani and penning gauges developed during this study had made good characteristics compared with the measured results of customized other gauges, and this results show the possibility of developing the gauges by ourselves in Korea. In order to make a competition with the customized gauges of other countries, it is necessary to upgrade several points to have good characteristics over the large range of the pressure. The new efforts will be made in developing the full scale gauge in the next year. (author)

Oxide-cathode activation and surface temperature calculation of electron cooler

International Nuclear Information System (INIS)

Li Jie; Yang Xiaodong; Mao Lijun; Li Guohong; Yuan Youjin; Liu Zhanwen; Zhang Junhui; Yang Xiaotian; Ma Xiaoming; Yan Tailai

2011-01-01

The pollution on electron gun ceramic insulation of electron cooler restricted the operation of electron cooler at HIRFL-CSR main ring. To cool and accumulate ion beam well, the pollution was cleared and a new oxide-coated cathode was assembled. The processes of cathode replacement,vacuum chamber baking-out, and thermal decomposition of coating binders and alkaline earth metal carbonates, and cathode activation are presented. The electron gun perveance of 10.6 μA/V 1.5 was attained under the heating power of 60 W. The typical surface temperature of oxide-coated cathode that is calculated through grey-body radiation is 1 108 K which shows a comparable result to the experimental measurement 1 078 K. The perveance growth of electron gun during the electron cooler operation is also explained by partial activation of the cathode. (authors)

Serologic surveillance of wild and pen-reared ring-necked pheasants (Phasianus colchicus) as a method of understanding disease reservoirs

Science.gov (United States)

Dwight, Ian; Coates, Peter S.; Stoute, Simone T.; Senties-Cue, C. Gabriel; Gharpure, Radhika V.; Pitesky, Maurice E.

2018-01-01

We investigated exposure to infectious diseases in wild (n=33) and pen-reared (n=12) Ring-necked Pheasants (Phasianus colchicus) in the Central Valley of California during 2014 and 2015. Serologic tests were positive for antibodies against hemorrhagic enteritis (HE), infectious bursal disease (IBD), and Newcastle disease (ND) viruses in both wild and pen-reared pheasants.

Theory of hollow cathode arc discharges. II. Metastable state balance inside the cathode. Application to argon

International Nuclear Information System (INIS)

Ferreira, C.M.; Delcroix, J.L.

1975-01-01

In the hollow cathode the metastable species are created by fast electrons, which are emitted by the cathode wall and injected in the plasma across a space-charge sheath, and destroyed by Maxwellian electrons. A detailed analysis of the different electronic destruction mechanisms in argon shows that the re-excitation up to 3p 5 4p states plays a very important role. Solutions of the metastable balance equation were obtained in a wide range of variation of the discharge parameters displaying the best conditions of operation to obtain high concentrations [fr

Modelling current transfer to cathodes in metal halide plasmas

International Nuclear Information System (INIS)

Benilov, M S; Cunha, M D; Naidis, G V

2005-01-01

This work is concerned with investigation of the main features of current transfer to cathodes under conditions characteristic of metal halide (MH) lamps. It is found that the presence of MHs in the gas phase results in a small decrease of the cathode surface temperature and of the near-cathode voltage drop in the diffuse mode of current transfer; the range of stability of the diffuse mode expands. Effects caused by a variation of the work function of the cathode surface owing to formation of a monolayer of alkali metal atoms on the surface are studied for particular cases where the monolayer is composed of sodium or caesium. It is found that the formation of the sodium monolayer affects the diffuse mode of current transfer only moderately and in the same direction that the presence of metal atoms in the gas phase affects it. Formation of the caesium monolayer produces a dramatic effect: the cathode surface temperature decreases very strongly, the diffuse-mode current-voltage characteristic becomes N-S-shaped

Durability and Performance of High Performance Infiltration Cathodes

DEFF Research Database (Denmark)

Samson, Alfred Junio; Søgaard, Martin; Hjalmarsson, Per

2013-01-01

The performance and durability of solid oxide fuel cell (SOFC) cathodes consisting of a porous Ce0.9Gd0.1O1.95 (CGO) infiltrated with nitrates corresponding to the nominal compositions La0.6Sr0.4Co1.05O3-δ (LSC), LaCoO3-δ (LC), and Co3O4 are discussed. At 600°C, the polarization resistance, Rp......, varied as: LSC (0.062Ωcm2)cathode was found to depend on the infiltrate firing temperature and is suggested to originate...... of the infiltrate but also from a better surface exchange property. A 450h test of an LSC-infiltrated CGO cathode showed an Rp with final degradation rate of only 11mΩcm2kh-1. An SOFC with an LSC-infiltrated CGO cathode tested for 1,500h at 700°C and 0.5Acm-2 (60% fuel, 20% air utilization) revealed no measurable...

Beam Dynamics Simulations of Optically-Enhanced Field Emission from Structured Cathodes

Energy Technology Data Exchange (ETDEWEB)

Seymour, A. [Northern Illinois U.; Grote, D. [LLNL, Livermore; Mihalcea, D. [Northern Illinois U.; Piot, P. [Fermilab; Vay, J.-L. [LBNL, Berkeley

2014-01-01

Structured cathodes - cathodes with a segmented emission surface - are finding an increasing number of applications and can be combined with a variety of emission mechanisms, including photoemission and field emission. These cathodes have been used to enhance the quantum efficiency of metallic cathodes when operated as plasmonic cathodes, have produced high-current electron bunches though field emission from multiple tips, and can be used to form beams with transverse segmentations necessary for improving the performance of accelerator-based light sources. In this report we present recent progress towards the development of finite-difference time-domain particle-in-cell simulations using the emission process in structured cathodes based on the WARP framework. The simulations give further insight on the localized source of the emitted electrons which could be used for additional high-fidelity start-to-end simulations of electron accelerators that employ this type of electron source.

NeuroPigPen: A Scalable Toolkit for Processing Electrophysiological Signal Data in Neuroscience Applications Using Apache Pig.

Science.gov (United States)

Sahoo, Satya S; Wei, Annan; Valdez, Joshua; Wang, Li; Zonjy, Bilal; Tatsuoka, Curtis; Loparo, Kenneth A; Lhatoo, Samden D

2016-01-01

The recent advances in neurological imaging and sensing technologies have led to rapid increase in the volume, rate of data generation, and variety of neuroscience data. This "neuroscience Big data" represents a significant opportunity for the biomedical research community to design experiments using data with greater timescale, large number of attributes, and statistically significant data size. The results from these new data-driven research techniques can advance our understanding of complex neurological disorders, help model long-term effects of brain injuries, and provide new insights into dynamics of brain networks. However, many existing neuroinformatics data processing and analysis tools were not built to manage large volume of data, which makes it difficult for researchers to effectively leverage this available data to advance their research. We introduce a new toolkit called NeuroPigPen that was developed using Apache Hadoop and Pig data flow language to address the challenges posed by large-scale electrophysiological signal data. NeuroPigPen is a modular toolkit that can process large volumes of electrophysiological signal data, such as Electroencephalogram (EEG), Electrocardiogram (ECG), and blood oxygen levels (SpO2), using a new distributed storage model called Cloudwave Signal Format (CSF) that supports easy partitioning and storage of signal data on commodity hardware. NeuroPigPen was developed with three design principles: (a) Scalability-the ability to efficiently process increasing volumes of data; (b) Adaptability-the toolkit can be deployed across different computing configurations; and (c) Ease of programming-the toolkit can be easily used to compose multi-step data processing pipelines using high-level programming constructs. The NeuroPigPen toolkit was evaluated using 750 GB of electrophysiological signal data over a variety of Hadoop cluster configurations ranging from 3 to 30 Data nodes. The evaluation results demonstrate that the toolkit

Usability of devices for self-injection: results of a formative study on a new disposable pen injector

Directory of Open Access Journals (Sweden)

Lange J

2014-06-01

Full Text Available Jakob Lange,1 Philipp Richard,1 Nick Bradley21Ypsomed AG, Burgdorf, Switzerland; 2Bergo, Glasgow, United KingdomAbstract: This article presents a late-stage formative usability study of a pen-injector platform device. Such devices are used for the subcutaneous delivery of biopharmaceuticals, primarily for self-administration by the patient. The study was conducted with a broad user population, defined to represent user characteristics across a range of indications. The goals of the study were to confirm that the pen could be used without recurring patterns of use errors leading to hazardous situations, to evaluate the comprehension of the instructions for use (IFU, and to determine if training is necessary. In the study, a total of 36 participants in six groups (health care providers, caregivers, adolescents, diabetics with retinopathy, diabetics with neuropathy, and patients with arthritis each read the IFU, prepared the device, and performed two simulated injections into an injection pad. Any use errors, near misses, or deviations from the IFU procedure were recorded. The overall success rate (injection completed by the participant without need for assistance was 94% for the first and 100% for the second injection. Ninety-two percent of the participants reported that they felt confident using the device, 100% found the IFU helpful, and 75% found the device positively comfortable to use. Overall, a total average of 3.35 deviations and errors per user and injection were recorded (there were no near misses. Subtracting the errors without any potential for negative consequences for the injection or the user (trivial deviations, as well as those related to attaching and removing the pen needle (independent of the design of the pen itself, led to an average of 1.31 potentially relevant deviations per user and injection. It was concluded that the pen injector together with the IFU could be safely and efficiently used by all user groups without any

Development of alloy-film coated dispenser cathode for terahertz vacuum electron devices application

International Nuclear Information System (INIS)

Barik, R.K.; Bera, A.; Raju, R.S.; Tanwar, A.K.; Baek, I.K.; Min, S.H.; Kwon, O.J.; Sattorov, M.A.; Lee, K.W.; Park, G.-S.

2013-01-01

High power terahertz vacuum electron devices demand high current density and uniform emission dispenser cathode. It was found that the coating of noble metals e.g., Os, Ir, and Re on the surface of tungsten dispenser cathodes enhances the emission capabilities and uniformity. Hence metal coated cathode might be the best candidate for terahertz devices applications. In this study, ternary-alloy-film cathode (2Os:2Re:1 W) and Os coated cathode have been developed and the results are presented. The cathodes made out of this alloy coating showed 1.5 times higher emission and 0.02 eV emission uniformity as compared to those of simply Os coated cathodes which can be used in terahertz devices application.

Development of alloy-film coated dispenser cathode for terahertz vacuum electron devices application

Energy Technology Data Exchange (ETDEWEB)

Barik, R. K.; Bera, A. [School of Electrical Engineering and Computer Science, Seoul National University, Seoul (Korea, Republic of); Raju, R. S. [Central Electronics Engineering Research Institute (CEERI), Rajasthan (India); Tanwar, A. K.; Baek, I. K.; Min, S. H.; Kwon, O. J.; Sattorov, M. A. [Department of Physics and Astronomy, Center for THz-Bio Application Systems, and Seoul-Teracom Inc., Seoul National University, Seoul (Korea, Republic of); Lee, K. W. [LIG Nex1, Seoul (Korea, Republic of); Park, G.-S., E-mail: gunsik@snu.ac.kr [School of Electrical Engineering and Computer Science, Seoul National University, Seoul (Korea, Republic of); Department of Physics and Astronomy, Center for THz-Bio Application Systems, and Seoul-Teracom Inc., Seoul National University, Seoul (Korea, Republic of); Advanced Institute of Convergence Technology, Suwon-si, Gyeonggi-do (Korea, Republic of)

2013-07-01

High power terahertz vacuum electron devices demand high current density and uniform emission dispenser cathode. It was found that the coating of noble metals e.g., Os, Ir, and Re on the surface of tungsten dispenser cathodes enhances the emission capabilities and uniformity. Hence metal coated cathode might be the best candidate for terahertz devices applications. In this study, ternary-alloy-film cathode (2Os:2Re:1 W) and Os coated cathode have been developed and the results are presented. The cathodes made out of this alloy coating showed 1.5 times higher emission and 0.02 eV emission uniformity as compared to those of simply Os coated cathodes which can be used in terahertz devices application.

Probabilistic modelling of the high-pressure arc cathode spot displacement dynamic

International Nuclear Information System (INIS)

Coulombe, Sylvain

2003-01-01

A probabilistic modelling approach for the study of the cathode spot displacement dynamic in high-pressure arc systems is developed in an attempt to interpret the observed voltage fluctuations. The general framework of the model allows to define simple, probabilistic displacement rules, the so-called cathode spot dynamic rules, for various possible surface states (un-arced metal, arced, contaminated) and to study the resulting dynamic of the cathode spot displacements over one or several arc passages. The displacements of the type-A cathode spot (macro-spot) in a magnetically rotating arc using concentric electrodes made up of either clean or contaminated metal surfaces is considered. Experimental observations for this system revealed a 1/f -tilde1 signature in the frequency power spectrum (FPS) of the arc voltage for anchoring arc conditions on the cathode (e.g. clean metal surface), while it shows a 'white noise' signature for conditions favouring a smooth movement (e.g. oxide-contaminated cathode surface). Through an appropriate choice of the local probabilistic displacement rules, the model is able to correctly represent the dynamic behaviours of the type-A cathode spot, including the FPS for the arc elongation (i.e. voltage) and the arc erosion trace formation. The model illustrates that the cathode spot displacements between re-strikes can be seen as a diffusion process with a diffusion constant which depends on the surface structure. A physical interpretation for the jumping probability associated with the re-strike event is given in terms of the electron emission processes across dielectric contaminants present on the cathode surface

Oxygen reduction kinetics on graphite cathodes in sediment microbial fuel cells.

Science.gov (United States)

Renslow, Ryan; Donovan, Conrad; Shim, Matthew; Babauta, Jerome; Nannapaneni, Srilekha; Schenk, James; Beyenal, Haluk

2011-12-28

Sediment microbial fuel cells (SMFCs) have been used as renewable power sources for sensors in fresh and ocean waters. Organic compounds at the anode drive anodic reactions, while oxygen drives cathodic reactions. An understanding of oxygen reduction kinetics and the factors that determine graphite cathode performance is needed to predict cathodic current and potential losses, and eventually to estimate the power production of SMFCs. Our goals were to (1) experimentally quantify the dependence of oxygen reduction kinetics on temperature, electrode potential, and dissolved oxygen concentration for the graphite cathodes of SMFCs and (2) develop a mechanistic model. To accomplish this, we monitored current on polarized cathodes in river and ocean SMFCs. We found that (1) after oxygen reduction is initiated, the current density is linearly dependent on polarization potential for both SMFC types; (2) current density magnitude increases linearly with temperature in river SMFCs but remains constant with temperature in ocean SMFCs; (3) the standard heterogeneous rate constant controls the current density temperature dependence; (4) river and ocean SMFC graphite cathodes have large potential losses, estimated by the model to be 470 mV and 614 mV, respectively; and (5) the electrochemical potential available at the cathode is the primary factor controlling reduction kinetic rates. The mechanistic model based on thermodynamic and electrochemical principles successfully fit and predicted the data. The data, experimental system, and model can be used in future studies to guide SMFC design and deployment, assess SMFC current production, test cathode material performance, and predict cathode contamination.

Evaluation of 1991--1992 brood overwinter-reared coho released from net pens in Youngs Bay, Oregon. Final completion report

International Nuclear Information System (INIS)

Hirose, P.S.

1997-01-01

Funding from Bonneville Power Administration was provided to the Oregon Department of Fish and Wildlife and the Clatsop County Economic Development Council's Fisheries Project to identify and develop terminal fishing opportunities. The 1991 and 1992 brood fingerling coho from Oregon Department of Fish and Wildlife hatcheries were successfully reared during the winter period to smolt stage in Youngs Bay utilizing floating net pens. Based on coded-wire-tag recoveries during 1991--93 from 2-week net-pen acclimation releases, total accountability of coho adults averaged 40,540 fish, with the Youngs Bay commercial harvest accounting for 39%. With reduced ocean harvest impacts during 1994 and 1995, 92% of 51,640 coho in 1994 and 68% of 23,599 coho in 1995 (based on coded-wire-tag recoveries) were accounted for in the Youngs Bay commercial fishery for combined 2-week and overwinter acclimation net-pen releases. Overwinter net-pen acclimation coho accounted for 35,063 and 15,775 coho adults in 1994 and 1995 with 93% and 68% accountable in the Youngs Bay commercial harvest. Based on coded-wire-tag recoveries, less than 1% of the adults resulting from releases at Youngs Bay net pens strayed to hatcheries, while none were recovered on spawning ground surveys during 1991--95. The highest survival rates were observed for 1991 and 1992 brood overwinter coho released in early May. Time of release, not rearing strategy, appears to be the determining factor affecting survival in Youngs Bay

Thermoplastic polymers surfaces for Dip-Pen Nanolithography of oligonucleotides

International Nuclear Information System (INIS)

Suriano, Raffaella; Biella, Serena; Cesura, Federico; Levi, Marinella; Turri, Stefano

2013-01-01

Different thermoplastic polymers were spin-coated to prepare smooth surfaces for the direct deposition of end-group modified oligonucleotides by Dip-Pen Nanolithography. A study of the diffusion process was done in order to investigate the dependence of calibration coefficient and quality of deposited features on environmental parameters (temperature, relative humidity) and ink's molecular weight and functionality. The optimization of the process parameters led to the realization of high quality and density nanoarrays on plastics.

Comparison of hollow cathode discharge plasma configurations

International Nuclear Information System (INIS)

Farnell, Casey C; Farnell, Cody C; Williams, John D

2011-01-01

Hollow cathodes used in plasma contactor and electric propulsion devices provide electrons for sustaining plasma discharges and enabling plasma bridge neutralization. Life tests show erosion on hollow cathodes exposed to the plasma environment produced in the region downstream of these devices. To explain the observed erosion, plasma flow field measurements are presented for hollow cathode generated plasmas using both directly immersed probes and remotely located plasma diagnostics. Measurements on two cathode discharge configurations are presented: (1) an open, no magnetic field configuration and (2) a setup simulating the discharge chamber environment of an ion thruster. In the open cathode configuration, large amplitude plasma potential oscillations, ranging from 20 to 85 V within a 34 V discharge, were observed using a fast response emissive probe. These oscillations were observed over a dc potential profile that included a well-defined potential hill structure. A remotely located electrostatic analyzer (ESA) was used to measure the energy of ions produced within the plasma, and energies were detected that met, and in some cases exceeded, the peak oscillatory plasma potentials detected by the emissive probe. In the ion thruster discharge chamber configuration, plasma potentials from the emissive probe again agreed with ion energies recorded by the remotely located ESA; however, much lower ion energies were detected compared with the open configuration. A simplified ion-transit model that uses temporal and spatial plasma property measurements is presented and used to predict far-field plasma streaming properties. Comparisons between the model and remote measurements are presented.

Molten carbonate fuel cell cathode with mixed oxide coating

Science.gov (United States)

Hilmi, Abdelkader; Yuh, Chao-Yi

2013-05-07

A molten carbonate fuel cell cathode having a cathode body and a coating of a mixed oxygen ion conductor materials. The mixed oxygen ion conductor materials are formed from ceria or doped ceria, such as gadolinium doped ceria or yttrium doped ceria. The coating is deposited on the cathode body using a sol-gel process, which utilizes as precursors organometallic compounds, organic and inorganic salts, hydroxides or alkoxides and which uses as the solvent water, organic solvent or a mixture of same.

Measurements of hot electrons in the Extrap T1 reversed-field pinch

Science.gov (United States)

Welander, A.; Bergsåker, H.

1998-02-01

The presence of an anisotropic energetic electron population in the edge region is a characteristic feature of reversed-field pinch (RFP) plasmas. In the Extrap T1 RFP, the anisotropic, parallel heat flux in the edge region measured by calorimetry was typically several hundred 0741-3335/40/2/011/img1. To gain more insight into the origin of the hot electron component and to achieve time resolution of the hot electron flow during the discharge, a target probe with a soft x-ray monitor was designed, calibrated and implemented. The x-ray emission from the target was measured with a surface barrier detector covered with a set of different x-ray filters to achieve energy resolution. A calibration in the range 0.5-2 keV electron energy was performed on the same target and detector assembly using a 0741-3335/40/2/011/img2 cathode electron gun. The calibration data are interpolated and extrapolated numerically. A directional asymmetry of more than a factor of 100 for the higher energy electrons is observed. The hot electrons are estimated to constitute 10% of the total electron density at the edge and their energy distribution is approximated by a half-Maxwellian with a temperature slightly higher than the central electron temperature. Scalings with plasma current, as well as correlations with local 0741-3335/40/2/011/img3 measurements and radial dependences, are presented.

Value-added utilisation of recycled concrete in hot-mix asphalt.

Science.gov (United States)

Wong, Yiik Diew; Sun, Darren Delai; Lai, Dickson

2007-01-01

The feasibility of partial substitution of granite aggregate in hot-mix asphalt (HMA) with waste concrete aggregate was investigated. Three hybrid HMA mixes incorporating substitutions of granite fillers/fines with 6%, 45% untreated, and 45% heat-treated concrete were evaluated by the Marshall mix design method; the optimum binder contents were found to be 5.3%, 6.5% and 7.0% of grade Pen 60/70 bitumen, respectively. All three hybrid mixes satisfied the Marshall criteria of the Singapore Land Transport Authority (LTA) W3B wearing course specification. The hybrid mix with 6% concrete fillers gave comparable resilient modulus and creep resistance as the conventional W3B mix, while hybrid mixes with higher concrete substitutions achieved better performance. X-ray diffraction (XRD) showed the distinct presence of free lime in the heat-treated concrete, while the scanning electron microscope (SEM) provided an in-depth perspective of the concrete grains in the HMA matrix. The results suggest feasible use of waste concrete as partial aggregate substitution in HMA.

Freestanding graphene/MnO2 cathodes for Li-ion batteries

Directory of Open Access Journals (Sweden)

Şeyma Özcan

2017-09-01

Full Text Available Different polymorphs of MnO2 (α-, β-, and γ- were produced by microwave hydrothermal synthesis, and graphene oxide (GO nanosheets were prepared by oxidation of graphite using a modified Hummers’ method. Freestanding graphene/MnO2 cathodes were manufactured through a vacuum filtration process. The structure of the graphene/MnO2 nanocomposites was characterized using X-ray diffraction (XRD and Raman spectroscopy. The surface and cross-sectional morphologies of freestanding cathodes were investigated by scanning electron microcopy (SEM. The charge–discharge profile of the cathodes was tested between 1.5 V and 4.5 V at a constant current of 0.1 mA cm−2 using CR2016 coin cells. The initial specific capacity of graphene/α-, β-, and γ-MnO2 freestanding cathodes was found to be 321 mAhg−1, 198 mAhg−1, and 251 mAhg−1, respectively. Finally, the graphene/α-MnO2 cathode displayed the best cycling performance due to the low charge transfer resistance and higher electrochemical reaction behavior. Graphene/α-MnO2 freestanding cathodes exhibited a specific capacity of 229 mAhg−1 after 200 cycles with 72% capacity retention.

Study on pulsed current cathodic protection in a simulated system

Energy Technology Data Exchange (ETDEWEB)

Yan, Milin; Li, Helin [Xi' an Jiao Tong Universitiy (China)]|[Tubular Goods Research Center of China National Petroleum Corp. (China); Qiu, Yubing; Guo, Xingpeng [Hua Zhong University of Science and Techonology (China)

2004-07-01

The pulsed current cathodic protection (PCCP) is a new cathodic protection (CP) technology and shows more advantages over the conventional DC cathodic protection (DCCP) in oil well casing system. However, little information about PCCP is reported. In this research, a simulated CP system was set up in a pool of 3.5 m x 2.0 m x 3.0 m size, in which the effects of the square wave pulsed current (SWPC) parameters (amplitude: IA, frequency: f, duty cycle: P), auxiliary anode distance (d) and media conductivity ({mu}) on the cathodic potential (E) distribution were studied, and the protection effects of PCCP and DCCP were compared. The results show that with increase of the square wave parameters (IA, f, P), the E distribution becomes more negative and the effects of each current parameter are relate closely to the cathode polarizing state. Only with suitable square wave parameters can the whole cathode be effectively protected. With increase of d and {mu}, the E distribution becomes more uniform. Compared with DCCP system, PCCP system has much more uniform E distribution, costs less average current, and gains much better protection effects. Further, the mechanism of PCCP was analyzed. (authors)

Testing a GaAs cathode in SRF gun

International Nuclear Information System (INIS)

Wang, E.; Kewisch, J.; Ben-Zvi, I.; Burrill, A.; Rao, T.; Wu, Q.; Holmes, D.

2011-01-01

RF electron guns with a strained superlattice GaAs cathode are expected to generate polarized electron beams of higher brightness and lower emittance than do DC guns, due to their higher field gradient at the cathode's surface and lower cathode temperature. We plan to install a bulk GaAs:Cs in a SRF gun to evaluate the performance of both the gun and the cathode in this environment. The status of this project is: In our 1.3 GHz 1/2 cell SRF gun, the vacuum can be maintained at nearly 10 -12 Torr because of cryo-pumping at 2K. With conventional activation of bulk GaAs, we obtained a QE of 10% at 532 nm, with lifetime of more than 3 days in the preparation chamber and have shown that it can survive in transport from the preparation chamber to the gun. The beam line has been assembled and we are exploring the best conditions for baking the cathode under vacuum. We report here the progress of our test of the GaAs cathode in the SRF gun. Future particle accelerators, such as eRHIC and the ILC require high-brightness, high-current polarized electrons. Strained superlattice GaAs:Cs has been shown to be an efficient cathode for producing polarized electrons. Activation of GaAs with Cs,O(F) lowers the electron affinity and makes it energetically possible for all the electrons, excited into the conduction band that drift or diffuse to the emission surface, to escape into the vacuum. Presently, all operating polarized electron sources, such as the CEBAF, are DC guns. In these devices, the excellent ultra-high vacuum extends the lifetime of the cathode. However, the low field gradient on the photocathode's emission surface of the DC guns limits the beam quality. The higher accelerating gradients, possible in the RF guns, generate a far better beam. Until recently, most RF guns operated at room temperature, limiting the vacuum to ∼10 -9 Torr. This destroys the GaAs's NEA surface. The SRF guns combine the excellent vacuum conditions of DC guns and the high accelerating

Improvements in the injection system of the Canadian Penning trap mass spectrometer

CERN Document Server

Clark, J; Boudreau, C; Buchinger, F; Crawford, J E; Gulick, S; Hardy, J C; Heinz, A; Lee, J K P; Moore, R B; Savard, G; Seweryniak, D; Sharma, K S; Sprouse, G; Vaz, J; Wang, J C; Zhou, Z

2003-01-01

The Canadian Penning Trap (CPT) mass spectrometer is designed to make precise mass measurements on a variety of stable and short-lived isotopes. Modifications to the injection system of the CPT have been implemented in recent months, the purpose being to more efficiently collect and transfer weakly-produced reaction products from the target to the Penning trap. These include a magnetic triplet situated after the target chamber to increase the acceptance of the Enge spectrograph, a velocity filter to more effectively separate the beam from the reaction products and the replacement of the Paul trap with a linear trap resulting in more efficient capture and accumulation of ions from the ion cooler. This paper will discuss these recent modifications and how they have increased our ability in making mass measurements on isotopes of low abundance, including those from a sup 2 sup 5 sup 2 Cf fission source.

Cathode fall measurement in a dielectric barrier discharge in helium

Energy Technology Data Exchange (ETDEWEB)

Hao, Yanpeng; Zheng, Bin; Liu, Yaoge [School of Electric Power, South China University of Technology, Guangzhou 510640 (China)

2013-11-15

A method based on the “zero-length voltage” extrapolation is proposed to measure cathode fall in a dielectric barrier discharge. Starting, stable, and discharge-maintaining voltages were measured to obtain the extrapolation zero-length voltage. Under our experimental conditions, the “zero-length voltage” gave a cathode fall of about 185 V. Based on the known thickness of the cathode fall region, the spatial distribution of the electric field strength in dielectric barrier discharge in atmospheric helium is determined. The strong cathode fall with a maximum field value of approximately 9.25 kV/cm was typical for the glow mode of the discharge.

Space-charge-limited currents for cathodes with electric field enhanced geometry

Energy Technology Data Exchange (ETDEWEB)

Lai, Dingguo, E-mail: laidingguo@nint.ac.cn; Qiu, Mengtong; Xu, Qifu [State Key Laboratory of Intense Pulsed Radiation Simulation and Effect, Northwest Institute of Nuclear Technology, Xi' an 701124 (China); Huang, Zhongliang [Department of Engineering Physics, Tsinghua University, Beijing 100084 (China)

2016-08-15

This paper presents the approximate analytic solutions of current density for annulus and circle cathodes. The current densities of annulus and circle cathodes are derived approximately from first principles, which are in agreement with simulation results. The large scaling laws can predict current densities of high current vacuum diodes including annulus and circle cathodes in practical applications. In order to discuss the relationship between current density and electric field on cathode surface, the existing analytical solutions of currents for concentric cylinder and sphere diodes are fitted from existing solutions relating with electric field enhancement factors. It is found that the space-charge-limited current density for the cathode with electric-field enhanced geometry can be written in a general form of J = g(β{sub E}){sup 2}J{sub 0}, where J{sub 0} is the classical (1D) Child-Langmuir current density, β{sub E} is the electric field enhancement factor, and g is the geometrical correction factor depending on the cathode geometry.

Resonant cavity operation of a virtual cathode oscillator

International Nuclear Information System (INIS)

Fazio, M.V.; Hoeberling, R.F.

1986-01-01

Gigawatt level virtual cathode sources have been proposed for several applications. These include microwave weapons and drivers for high-energy particle accelerators. Both of these require a microwave source with very high power output that is controllable in frequency and phase. A conventional virtual cathode oscillator will not meet these requirements. The addition of a resonant cavity surrounding the oscillating virtual cathode either alone or pumped with a low-power injection signal, causing it to operate as an amplifier, could greatly influence the performance of this type of source making it more practical for accelerator and weapon applications. The progress on an experiment to test these concepts will be discussed

A cold cathode of a gas-discharge electron-ion gun

International Nuclear Information System (INIS)

1974-01-01

A cold cathode of a gas-discharge electron-ion gun is constructed in order to continuously replace the eroded material by feeding a wire or a set of coaxial cylinders in the spot where the ions hit the cathode. In this way, the form of the cathode and the electric-field configuration is preserved which guarantees the conservation of a sharp narrow electron beam profile

Vegetation survey of Pen Branch and Four Mile Creek wetlands

Energy Technology Data Exchange (ETDEWEB)

1992-01-01

One hundred-fifty plots were recently sampled (vegetational sampling study) at the Savannah River Site (SRS). An extensive characterization of the vascular flora, in four predetermined strata (overstory, Understory, shrub layer, and ground cover), was undertaken to determine dominance, co-dominance, and the importance value (I.V.) of each species. These results will be used by the Savannah River Laboratory (SRL) to evaluate the environmental status of Four Mile Creek, Pen Branch, and two upland pine stands. Objectives of this study were to: Describe in detail the plant communities previously mapped with reference to the topography and drainage, including species of plants present: Examine the successional trends within each sampling area and describe the extent to which current vegetation communities have resulted from specific earlier vegetation disturbances (e.g., logging and grazing); describe in detail the botanical field techniques used to sample the flora; describe the habitat and location of protected and/or rare species of plants; and collect and prepare plant species as herbarium quality specimens. Sampling was conducted at Four Mile Creek and Pen Branch, and in two upland pine plantations of different age growth.

Vegetation survey of Pen Branch and Four Mile Creek wetlands

Energy Technology Data Exchange (ETDEWEB)

1992-10-01

One hundred-fifty plots were recently sampled (vegetational sampling study) at the Savannah River Site (SRS). An extensive characterization of the vascular flora, in four predetermined strata (overstory, Understory, shrub layer, and ground cover), was undertaken to determine dominance, co-dominance, and the importance value (I.V.) of each species. These results will be used by the Savannah River Laboratory (SRL) to evaluate the environmental status of Four Mile Creek, Pen Branch, and two upland pine stands. Objectives of this study were to: Describe in detail the plant communities previously mapped with reference to the topography and drainage, including species of plants present: Examine the successional trends within each sampling area and describe the extent to which current vegetation communities have resulted from specific earlier vegetation disturbances (e.g., logging and grazing); describe in detail the botanical field techniques used to sample the flora; describe the habitat and location of protected and/or rare species of plants; and collect and prepare plant species as herbarium quality specimens. Sampling was conducted at Four Mile Creek and Pen Branch, and in two upland pine plantations of different age growth.

Pressurized air cathodes for enhanced stability and power generation by microbial fuel cells

Science.gov (United States)

He, Weihua; Yang, Wulin; Tian, Yushi; Zhu, Xiuping; Liu, Jia; Feng, Yujie; Logan, Bruce E.

2016-11-01

Large differences between the water and air pressure in microbial fuel cells (MFCs) can deform and damage cathodes. To avoid deformation, the cathode air pressure was controlled to balance pressure differences between the air and water. Raising the air pressures from 0 to 10 kPa at a set cathode potential of -0.3 V (versus Ag/AgCl) enhanced cathode performance by 17%, but pressures ≥25 kPa decreased current and resulted in air leakage into the solution. Matching the air pressure with the water pressure avoided cathode deformation and improved performance. The maximum power density increased by 15%, from 1070 ± 20 to 1230 ± 70 mW m-2, with balanced air and water pressures of 10-25 kPa. Oxygen partial pressures ≥12.5 kPa in the cathode compartment maintained the oxygen reduction rate to be within 92 ± 1% of that in ambient air. The use of pressurized air flow through the cathode compartments can enable closer spacing of the cathodes compared to passive gas transfer systems, which could make the reactor design more compact. The energy cost of pressurizing the cathodes was estimated to be smaller than the increase in power that resulted from the use of pressurized cathodes.

Pressurized air cathodes for enhanced stability and power generation by microbial fuel cells

KAUST Repository

He, Weihua

2016-09-30

Large differences between the water and air pressure in microbial fuel cells (MFCs) can deform and damage cathodes. To avoid deformation, the cathode air pressure was controlled to balance pressure differences between the air and water. Raising the air pressures from 0 to 10 kPa at a set cathode potential of −0.3 V (versus Ag/AgCl) enhanced cathode performance by 17%, but pressures ≥25 kPa decreased current and resulted in air leakage into the solution. Matching the air pressure with the water pressure avoided cathode deformation and improved performance. The maximum power density increased by 15%, from 1070 ± 20 to 1230 ± 70 mW m, with balanced air and water pressures of 10–25 kPa. Oxygen partial pressures ≥12.5 kPa in the cathode compartment maintained the oxygen reduction rate to be within 92 ± 1% of that in ambient air. The use of pressurized air flow through the cathode compartments can enable closer spacing of the cathodes compared to passive gas transfer systems, which could make the reactor design more compact. The energy cost of pressurizing the cathodes was estimated to be smaller than the increase in power that resulted from the use of pressurized cathodes.

Nano-structured textiles as high-performance aqueous cathodes for microbial fuel cells

KAUST Repository

Xie, Xing; Pasta, Mauro; Hu, Liangbing; Yang, Yuan; McDonough, James; Cha, Judy; Criddle, Craig S.; Cui, Yi

2011-01-01

A carbon nanotube (CNT)-textile-Pt cathode for aqueous-cathode microbial fuel cells (MFCs) was prepared by electrochemically depositing Pt nanoparticles on a CNT-textile. An MFC equipped with a CNT-textile-Pt cathode revealed a 2.14-fold maximum power density with only 19.3% Pt loading, compared to that with a commercial Pt coated carbon cloth cathode. © 2011 The Royal Society of Chemistry.

The cooperative electrochemical oxidation of chlorophenols in anode-cathode compartments

International Nuclear Information System (INIS)

Wang Hui; Wang Jianlong

2008-01-01

By using a self-made carbon/polytetrafluoroethylene (C/PTFE) O 2 -fed as the cathode and Ti/IrO 2 /RuO 2 as the anode, the degradation of three organic compounds (phenol, 4-chlorophenol, and 2,4-dichlorophenol) was investigated in the diaphragm (with terylene as diaphragm material) electrolysis device by electrochemical oxidation process. The result indicated that the concentration of hydrogen peroxide (H 2 O 2 ) was 8.3 mg/L, and hydroxyl radical (HO·) was determined in the cathodic compartment by electron spin resonance spectrum (ESR). The removal efficiency for organic compounds reached about 90% after 120 min, conforming to the sequence of phenol, 4-chlorophenol, and 2,4-dichlorophenol. And the dechlorination degree of 4-chlorophenol exceeded 90% after 80 min. For H 2 O 2 , HO· existed in the catholyte and reduction dechlorination at the cathode, the mineralization of organics in the cathodic compartment was better than that in the anodic compartment. The degradation of organics was supposed to be cooperative oxidation by direct or indirect electrochemical oxidation at the anode and H 2 O 2 , HO· produced by oxygen reduction at the cathode. High-performance liquid chromatography (HPLC) allowed identifying phenol as the dechlorination product of 4-chlorophenol in the cathodic compartment, and hydroquinone, 4-chlorocatechol, benzoquinone, maleic, fumaric, oxalic, and formic acids as the main oxidation intermediates in the cathodic and anodic compartments. A reaction scheme involving all these intermediates was proposed

Application of the CO2-PENS risk analysis tool to the Rock Springs Uplift, Wyoming

Science.gov (United States)

Stauffer, P.H.; Pawar, R.J.; Surdam, R.C.; Jiao, Z.; Deng, H.; Lettelier, B.C.; Viswanathan, H.S.; Sanzo, D.L.; Keating, G.N.

2011-01-01

We describe preliminary application of the CO2-PENS performance and risk analysis tool to a planned geologic CO2 sequestration demonstration project in the Rock Springs Uplift (RSU), located in south western Wyoming. We use data from the RSU to populate CO2-PENS, an evolving system-level modeling tool developed at Los Alamos National Laboratory. This tool has been designed to generate performance and risk assessment calculations for the geologic sequestration of carbon dioxide. Our approach follows Systems Analysis logic and includes estimates of uncertainty in model parameters and Monte-Carlo simulations that lead to probabilistic results. Probabilistic results provide decision makers with a range in the likelihood of different outcomes. Herein we present results from a newly implemented approach in CO 2-PENS that captures site-specific spatially coherent details such as topography on the reservoir/cap-rock interface, changes in saturation and pressure during injection, and dip on overlying aquifers that may be impacted by leakage upward through wellbores and faults. We present simulations of CO 2 injection under different uncertainty distributions for hypothetical leaking wells and faults. Although results are preliminary and to be used only for demonstration of the approach, future results of the risk analysis will form the basis for a discussion on methods to reduce uncertainty in the risk calculations. Additionally, we present ideas on using the model to help locate monitoring equipment to detect potential leaks. By maintaining site-specific details in the CO2-PENS analysis we provide a tool that allows more logical presentations to stakeholders in the region. ?? 2011 Published by Elsevier Ltd.

Using insulin pen needles up to five times does not affect needle tip shape nor increase pain intensity.

Science.gov (United States)

Puder, Jardena J; Atar, Michael; Muller, Beat; Pavan, Marco; Keller, Ulrich

2005-02-01

Reusing insulin pen needles could help to reduce the increasing economic burden of diabetes. We tested the hypothesis that reusing insulin pen needles leads to needle tip deformity and increased pain. Three blinded reviewers assessed 123 electron microscope pictures analyzing needle tip deformity of insulin pen needles used up to four times by diabetic subjects and up to five times by blinded non-diabetic volunteers. The estimated frequency of needle use was correlated to the actual number of needle use. Pain intensity and unpleasantness of each injection were measured by a visual analogue scale and their differences analyzed by Kruskal-Wallis analysis of variance. Unused needles could be differentiated visually from used needles. However, there was no correlation between the actual and guessed number of times a needle was used (r = 0.07, P = 0.2). Evaluating all 270 injections, neither pain intensity nor unpleasantness increased with repeated injections of the same needles in people with diabetes (P = 0.1 and 0.96) and in the volunteers (P = 0.63 and 0.92). Using pen needles four to five times does not lead to progressive needle tip deformity and does not increase pain intensity or unpleasantness, but could increase convenience and lead to substantial financial savings in Europe of around EUR 100 million/year.