Sample records for organ bath experiments

  1. Hydrothermal organic synthesis experiments

    NASA Technical Reports Server (NTRS)

    Shock, Everett L.

    1992-01-01

    Ways in which heat is useful in organic synthesis experiments are described, and experiments on the hydrothermal destruction and synthesis of organic compounds are discussed. It is pointed out that, if heat can overcome kinetic barriers to the formation of metastable states from reduced or oxidized starting materials, abiotic synthesis under hydrothermal conditions is a distinct possibility. However, carefully controlled experiments which replicate the descriptive variables of natural hydrothermal systems have not yet been conducted with the aim of testing the hypothesis of hydrothermal organic systems.

  2. Hydrothermal organic synthesis experiments

    NASA Technical Reports Server (NTRS)

    Shock, Everett L.

    1992-01-01

    The serious scientific debate about spontaneous generation which raged for centuries reached a climax in the nineteenth century with the work of Spallanzani, Schwann, Tyndall, and Pasteur. These investigators demonstrated that spontaneous generation from dead organic matter does not occur. Although no aspects of these experiments addressed the issue of whether organic compounds could be synthesized abiotically, the impact of the experiments was great enough to cause many investigators to assume that life and its organic compounds were somehow fundamentally different than inorganic compounds. Meanwhile, other nineteenth-century investigators were showing that organic compounds could indeed be synthesized from inorganic compounds. In 1828 Friedrich Wohler synthesized urea in an attempt to form ammonium cyanate by heating a solution containing ammonia and cyanic acid. This experiment is generally recognized to be the first to bridge the artificial gap between organic and inorganic chemistry, but it also showed the usefulness of heat in organic synthesis. Not only does an increase in temperature enhance the rate of urea synthesis, but Walker and Hambly showed that equilibrium between urea and ammonium cyanate was attainable and reversible at 100 C. Wohler's synthesis of urea, and subsequent syntheses of organic compounds from inorganic compounds over the next several decades dealt serious blows to the 'vital force' concept which held that: (1) organic compounds owe their formation to the action of a special force in living organisms; and (2) forces which determine the behavior of inorganic compounds play no part in living systems. Nevertheless, such progress was overshadowed by Pasteur's refutation of spontaneous generation which nearly extinguished experimental investigations into the origins of life for several decades. Vitalism was dealt a deadly blow in the 1950's with Miller's famous spark-discharge experiments which were undertaken in the framework of the Oparin and Haldane hypotheses concerning the origin of life. These hypotheses were constructed on some basic assumptions which included a reduced atmosphere, and a low surface temperature for the early Earth. These ideas meshed well with the prevailing hypothesis of the 1940's and 50's that the Earth had formed through heterogeneous accretion of dust from a condensing solar nebula. Miller's experiments were extremely successful, and were followed by numerous other experiments by various investigators who employed a wide variety of energy sources for abiotic synthesis including spark discharges, ultra-violet radiation, heat, shock waves, plasmas, gamma rays, and other forms of energy. The conclusion reached from this body of work is that energy inputs can drive organic synthesis from a variety of inorganic starting materials.

  3. EnviRONment and other bath smelting processes for treating organic and ferrous wastes

    NASA Astrophysics Data System (ADS)

    Street, S.; Brooks, G.; Reilly, L.; Worner, H. K.

    1998-04-01

    In recent years, it has become apparent that bath smelting may be a suitable technology for treating wastes. Technologies developed by Molten Metal Technology, Ausmelt, Mintek, Techtronics, and the University of Wollongong utilize molten baths of metal and slag to process metal-containing wastes. This paper discusses the similarities and differences between these processes, focusing particularly on the EnvIRONment process.

  4. Bath Salts

    MedlinePLUS

    Synthetic cathinones, often called “bath salts,” are powerful, illegal, and can cause hallucinations and violent behavior, among other dangerous effects. Twitter Facebook RSS 582 Exposures Jan. 1, ...

  5. Bathing Beauties

    NSDL National Science Digital Library

    In past decades, bathing beauties might have meant beautiful people on a beach, but these "bathing beauties" are actually a collection of new bathing hut designs. They are, of course, beautiful indeed, and visitors with a droll curiosity in the world of seaside architecture, leisure studies, or other seaside pursuits will certainly find this site useful. The impetus for creating such a site was a recent international beach hut design competition, which was held at the National Centre for Craft & Design in the United Kingdom. On the site, visitors can view both the winners of the competition and the other entries as well. Understandably, the other entries are just scale model designs, but there are some real pippins among their number. If beach huts aren't enough, there are also some beachfront restaurant designs and a few boathouse designs as well.

  6. The behavior of organic components in copper recovery from electroless plating bath effluents using 3D electrode systems.

    PubMed

    Orhan, Gökhan; Gürmen, Sebahattin; Timur, Servet

    2004-08-30

    An electrochemical method was applied for the recovery of copper both from the spent solutions and from the rinse waters of electroless copper plating baths, containing copper sulfate, formaldehyde, quadrol, and NaOH. Experiments were conducted in a rotating packed cell (Rollschichtzelle) to investigate the effects of current density, electrolyte composition, temperature, and pH on the copper recovery. All the copper (final CCu=0.1 ppm) was recovered from the waste and rinse waters of chemical copper plating plants with 70% current efficiency by the electrochemical treatment in a rotating packed cell at 130 A/m2 current density, room temperature, with 5mm diameter cathode granules, with the presence of formaldehyde, and with a specific energy consumption of 3.2-3.5 kW h/kg Cu. On the other hand, final copper concentrations of 5 ppm were reached with 62% current efficiency and 5.5-5.8 kW h/kg Cu specific energy consumption, with electrolytes containing no formaldehyde. PMID:15302447

  7. Synthetic Cathinones ("Bath Salts")

    MedlinePLUS

    ... Synthetic Cathinones (“Bath Salts”) DrugFacts: Synthetic Cathinones (“Bath Salts”) Email Facebook Twitter Revised November 2012 The term “ ... Sky," "White Lightning," and “Scarface.” How Are Bath Salts Abused? Bath salts are typically taken orally, inhaled, ...

  8. The effects of normal and therapeutic baths on the central vascular organs of persons with healthy hearts, as measured by X-ray

    NASA Technical Reports Server (NTRS)

    Boehm, G.; Ekert, FR.

    1988-01-01

    According to current information, baths have a four-fold effect on the circulation: (1) Dilation or constriction is produced in the area of the blood vessels in the skin as a result of thermal, chemical or mechanical stimuli; (2) This reaction in the dermal vascular system produces a further effect on the central vessels in the extremities, the area of the splanchnicus, and other body cavities; (3) The reflect transposition of other organ systems, i.e., the respiratory organs, has a reaction on the circulation; and (4) The water pressure of the bath has a hydrostatic effect, i.e., on the one hand it empties peripheral veins more rapidly, and on the other it increases the intra-abdominal pressure and this reduces once again the circulation in the area of the splanchnicus.

  9. Confined compression and torsion experiments on a pHEMA gel in various bath concentrations.

    PubMed

    Roos, Reinder W; Petterson, Rob; Huyghe, Jacques M

    2013-06-01

    The constitutive behaviour of cartilaginous tissue is the result of complex interaction between electrical, chemical and mechanical forces. Electrostatic interactions between fixed charges and mobile ions are usually accounted for by means of Donnan osmotic pressure. Recent experimental data show, however, that the shear modulus of articular cartilage depends on ionic concentration even if the strain is kept constant. Poisson-Boltzmann simulations suggest that this dependence is intrinsic to the double-layer around the proteoglycan chains. In order to verify this premise, this study measures whether--at a given strain--this ionic concentration-dependent shear modulus is present in a polymerized hydroxy-ethyl-methacrylate gel or not. A combined 1D confined compression and torque experiment is performed on a thin cylindrical hydrogel sample, which is brought in equilibrium with, respectively, 1, 0.1 and 0.03 M NaCl. The sample was placed in a chamber that consists of a stainless steel ring placed on a sintered glass filter, and on top a sintered glass piston. Stepwise ionic loading was cascaded by stepwise 1D compression, measuring the total stress after equilibration of the sample. In addition, a torque experiment was interweaved by applying a harmonic angular displacement and measuring the torque, revealing the relation between aggregate shear modulus and salt concentration at a given strain. PMID:22926832

  10. Effects of MetalOrganic Chemical Vapour Deposition grown seed layer on the fabrication of well aligned ZnO nanorods by Chemical Bath Deposition

    Microsoft Academic Search

    Maria Elena Fragalà; Yana Aleeva; Graziella Malandrino

    2011-01-01

    Well aligned, long and uniform ZnO nanorods have been reproducibly fabricated adopting a two-steps Metal-Organic Chemical Vapour Deposition (MOCVD) and Chemical Bath Deposition (CBD) fabrication approaches. Thin (<100nm) ZnO buffer layers have been seeded on silicon substrates by MOCVD and ZnO layers have been subsequently grown, in form of well textured nanorods, using CBD. It has been found that the

  11. Modeling and experiment of dye-sensitized solar cell with vertically aligned ZnO nanorods through chemical bath deposition

    NASA Astrophysics Data System (ADS)

    Wahyuono, Ruri Agung; Risanti, Doty D.

    2015-01-01

    A theoretical model based on electron diffusion differential equation and Schottky barrier model was developed to determine the current-voltage characteristics of DSSC. To verify the model DSSC with ZnO nanorods photoelectrode which was chemically bath deposited onto the TCO was fabricated. According to modeling results, increasing of recombination current density J at these interfaces results in a decrease in Schottky barrier height ?b and therefore improves the photovoltage under the open-circuit condition. It is found that the open-circuit voltage remains constant when the TCO/ZnO Schottky barrier height was varied in the range of 0.45 - 0.6 eV. This theoretical model consistents with the experimental result in which the fabricated DSSCs can produce conversion efficiency in the range of 0.98 - 1.16%. The trend in photovoltage calculated in the theoretical model basically agrees with the experimental result, although the calculated photocurrent is somewhat over estimated compared to the experimental results. The model presents that the ideality factor for ZnO nanorods, which also contributes to the enhancement of photovoltage, increases in the range of 2.75 - 3.0 as the annealing temperature is increased in the experiment.

  12. Organic Experiments for Introductory Chemistry.

    ERIC Educational Resources Information Center

    Rayner-Canham, Geoff

    1985-01-01

    Describes test-tube organic chemistry procedures (using comparatively safe reagents) for the beginning student. These procedures are used to: examine differences between saturated and unsaturated hydrocarbons; compare structural isomers; and compare organic and inorganic acids and bases. (DH)

  13. Physiological evidence for the presence of a cis-trans isomerase of unsaturated fatty acids in Methylococcus capsulatus Bath to adapt to the presence of toxic organic compounds.

    PubMed

    Löffler, Claudia; Eberlein, Christian; Mäusezahl, Ines; Kappelmeyer, Uwe; Heipieper, Hermann J

    2010-07-01

    The physiology of the response in the methanotrophic bacterium Methylococcus capsulatus Bath towards thermal and solvent stress was studied. A systematic investigation of the toxic effects of organic compounds (chlorinated phenols and alkanols) on the growth of this bacterium was carried out. The sensitivity to the tested alkanols correlated with their chain length and hydrophobicity; methanol was shown to be an exception to which the cells showed a very high tolerance. This can be explained by the adaptation of these bacteria to growth on C1 compounds. On the other hand, M. capsulatus Bath was very sensitive towards the tested chlorinated phenols. The high toxic effect of phenolic compounds on methanotrophic bacteria might be explained by the occurrence of toxic reactive oxygen species. In addition, a physiological proof of the presence of cis-trans isomerization as a membrane-adaptive response mechanism in M. capsulatus was provided. This is the first report on physiological evidence for the presence of the unique postsynthetic membrane-adaptive response mechanism of the cis-trans isomerization of unsaturated fatty acids in a bacterium that does not belong to the genera Pseudomonas and Vibrio where this mechanism was already reported and described extensively. PMID:20487020

  14. What Are Bath Salts?

    MedlinePLUS

    ... Menu | Search Enter Search Term(s): Home + Drug Facts Anabolic Steroids Bath Salts Cocaine Cough and Cold Medicine (DXM ... Web site Citation Site Map Home Drug Facts Anabolic Steroids Bath Salts Cocaine Cough and Cold Medicine (DXM ...

  15. An Experiment to Quantitate Organically Bound Phosphate.

    ERIC Educational Resources Information Center

    Palmer, Richard E.

    1985-01-01

    Describes quick and easy experiments that yield quantitative information on a variety of levels, emphasize the concept of experimental controls, and integrate the experimental with the theoretical using the organic phosphates as the experimental system. Background information, list of materials needed, and procedures used are included. (JN)

  16. Organism support for life sciences spacelab experiments

    NASA Technical Reports Server (NTRS)

    Drake, G. L.; Heppner, D. B.

    1976-01-01

    This paper presents an overview of the U.S. life sciences laboratory concepts envisioned for the Shuttle/Spacelab era. The basic development approach is to provide a general laboratory facility supplemented by specific experiment hardware as required. The laboratory concepts range from small carry-on laboratories to fully dedicated laboratories in the Spacelab pressurized module. The laboratories will encompass a broad spectrum of research in biology and biomedicine requiring a variety of research organisms. The environmental control and life support of these organisms is a very important aspect of the success of the space research missions. Engineering prototype organism habitats have been designed and fabricated to be compatible with the Spacelab environment and the experiment requirements. These first-generation habitat designs and their subsystems have supported plants, cells/tissues, invertebrates, and small vertebrates in limited evaluation tests. Special handling and transport equipment required for the ground movement of the experiment organisms at the launch/landing site have been built and tested using these initial habitat prototypes.

  17. Occupational health experience with organic additives

    SciTech Connect

    Thiess, A.M.; Wellenreuther, G.

    1984-12-01

    For many decades, interest in occupational medicine has been focused on the wide variety of organic additives, which includes a large number of substances, for example, dyestuffs, pigments, and auxiliaries for the textile, leather, and paper industries. The reason is that, if the recommended precautions are not observed, there is a risk of exposure to most of these substances during both production and use. Moreover, over the years, some additives have caused concern and aroused suspicion regarding adverse effects on health. In order to deal with health problems in this field, it is important to be aware of how, what, and where occupational diseases or accidents arise. Much knowledge has been gained about these, and it would be an impossible task to give a systematic survey of the data that have accumulated, especially since it is necessary to take account of the problem of exposure to more than one substance. Thus an attempt is made to report on occupational health experience in general, and to demonstrate how an industrial hygienist may approach the many and various problems. Some epidemiological studies on organic additives (auramine, anthraquinone dyestuffs, organic dyes, etc.) are discussed.

  18. Risk factors of sudden death in the Japanese hot bath in the senior population

    Microsoft Academic Search

    Takashi Chiba; Misa Yamauchi; Naoki Nishida; Taeko Kaneko; Katsuaki Yoshizaki; Naofumi Yoshioka

    2005-01-01

    A series of experiments were carried out to clarify the cause of death and the risk factors related to sudden death in the Japanese senior population while bathing in a Japanese style “hot bath.” The biodynamic changes while bathing were carefully monitored under actual bathing situations occurring in both the winter and summer seasons. We observed double product (DP), total

  19. University of Bath Campus Masterplan

    E-print Network

    Burton, Geoffrey R.

    University of Bath Campus Masterplan Strategic Tree Review #12;#12;University of Bath Hyder.hyderconsulting.com University of Bath Campus Masterplan Strategic Tree Review Date 22nd August 2012 This report has been prepared for University of Bath in accordance with the terms and conditions of appointment. Hyder

  20. 10. TYPICAL BATH IN MEN'S BATH HALL. Hot Springs ...

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

    10. TYPICAL BATH IN MEN'S BATH HALL. - Hot Springs National Park, Bathhouse Row, Buckstaff Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 Mile North of U.S. Highway 70, Hot Springs, Garland County, AR

  1. Mixed ether bath for electrodeposition of aluminum

    NASA Technical Reports Server (NTRS)

    Lui, K.

    1969-01-01

    Anisole added to the bath mixture improves Brenner aluminum plating bath technique. Mixture has lower bath vapor-pressure and the electro-deposits obtained have greater physical strength than deposits from the Brenner bath.

  2. "Crown Ether" Synthesis: An Organic Laboratory Experiment.

    ERIC Educational Resources Information Center

    Field, Kurt W.; And Others

    1979-01-01

    This experiment is designed to acquaint the student with a macromolecular synthesis of a crown ether type compound. The starting materials are readily available and the product, a cyclic polyether, belongs to a class of compounds that has aroused the interest of chemist and biologist alike. (Author/BB)

  3. Solvent Selection for Recrystallization: An Undergraduate Organic Experiment.

    ERIC Educational Resources Information Center

    Baumann, Jacob B.

    1979-01-01

    This experiment develops the students' ability to carry out a simple recrystallization effectively, and demonstrates how a solvent may be selected or rejected for the recrystallization of a specific organic compound. (Author/BB)

  4. Experiment Results Microspectroscopy of Meteorites: Search for Organic Mineral Correlations

    E-print Network

    Peale, Robert E.

    Experiment Results Microspectroscopy of Meteorites: Search for Organic ­ Mineral Correlations M on the mineral species. Little is known about the spatial distribution and mineralogical relationships of organic molecules in meteorites. The amount and type of such molecules may depend on the mineral species

  5. Biodiesel Synthesis and Evaluation: An Organic Chemistry Experiment

    ERIC Educational Resources Information Center

    Bucholtz, Ehren C.

    2007-01-01

    A new lab esterification reaction based on biodiesel preparation and viscosity, which provides a model experience of industrial process to understand oxidation of vicinal alcohols by periodic acid, is presented. This new desertification experiment and periodate analysis of glycerol for the introductory organic chemistry laboratory provides an…

  6. 33 CFR 334.45 - Kennebec River, Bath Iron Works Shipyard, naval restricted area, Bath, Maine.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Kennebec River, Bath Iron Works Shipyard, naval restricted area, Bath, Maine. 334...RESTRICTED AREA REGULATIONS § 334.45 Kennebec River, Bath Iron Works Shipyard, naval restricted area, Bath, Maine....

  7. 33 CFR 334.45 - Kennebec River, Bath Iron Works Shipyard, naval restricted area, Bath, Maine.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Kennebec River, Bath Iron Works Shipyard, naval restricted area, Bath, Maine. 334...RESTRICTED AREA REGULATIONS § 334.45 Kennebec River, Bath Iron Works Shipyard, naval restricted area, Bath, Maine....

  8. 33 CFR 334.45 - Kennebec River, Bath Iron Works Shipyard, naval restricted area, Bath, Maine.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Kennebec River, Bath Iron Works Shipyard, naval restricted area, Bath, Maine. 334...RESTRICTED AREA REGULATIONS § 334.45 Kennebec River, Bath Iron Works Shipyard, naval restricted area, Bath, Maine....

  9. 33 CFR 334.45 - Kennebec River, Bath Iron Works Shipyard, naval restricted area, Bath, Maine.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Kennebec River, Bath Iron Works Shipyard, naval restricted area, Bath, Maine. 334...RESTRICTED AREA REGULATIONS § 334.45 Kennebec River, Bath Iron Works Shipyard, naval restricted area, Bath, Maine....

  10. Environmental geology of Bath, England

    Microsoft Academic Search

    G. A. Kellaway

    1995-01-01

    The hot springs of Bath, England, have been of importance to man for hundreds of years. It was a famous spa in Roman times. Subsequently, the springs were used during the 17th through the 20th centuries and extensive urban and commercial properties were developed at Bath using the water for medical and tourist-oriented activities. With urban and commercial development in

  11. 33 CFR 165.104 - Safety Zone: Vessel Launches, Bath Iron Works, Kennebec River, Bath, Maine.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Bath Iron Works, Kennebec River, Bath, Maine. 165.104 Section 165.104 Navigation...Bath Iron Works, Kennebec River, Bath, Maine. (a) Location. The following...the Bath Iron Works Facility in Bath, Maine to a deployed position in the...

  12. Synthesis of Bisphenol Z: An Organic Chemistry Experiment

    ERIC Educational Resources Information Center

    Gregor, Richard W.

    2012-01-01

    A student achievable synthesis of bisphenol Z, 4,4'-(cyclohexane-1,1-diyl)diphenol, from the acid-catalyzed reaction of phenol with cyclohexanone is presented. The experiment exemplifies all the usual pedagogy for the standard topic of electrophilic aromatic substitution present in the undergraduate organic chemistry curriculum, while providing…

  13. Biodiesel from Seeds: An Experiment for Organic Chemistry

    ERIC Educational Resources Information Center

    Goldstein, Steven W.

    2014-01-01

    Plants can store the chemical energy required by their developing offspring in the form of triglycerides. These lipids can be isolated from seeds and then converted into biodiesel through a transesterification reaction. This second-year undergraduate organic chemistry laboratory experiment exemplifies the conversion of an agricultural energy…

  14. An Enzyme Kinetics Experiment for the Undergraduate Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Olsen, Robert J.; Olsen, Julie A.; Giles, Greta A.

    2010-01-01

    An experiment using [superscript 1]H NMR spectroscopy to observe the kinetics of the acylase 1-catalyzed hydrolysis of "N"-acetyl-DL-methionine has been developed for the organic laboratory. The L-enantiomer of the reactant is hydrolyzed completely in less than 2 h, and [superscript 1]H NMR spectroscopic data from a single sample can be worked up…

  15. Radical Recombination Kinetics: An Experiment in Physical Organic Chemistry.

    ERIC Educational Resources Information Center

    Pickering, Miles

    1980-01-01

    Describes a student kinetic experiment involving second order kinetics as well as displaying photochromism using a wide variety of techniques from both physical and organic chemistry. Describes measurement of (1) the rate of the recombination reaction; (2) the extinction coefficient; and (3) the ESR spectrometer signal. (Author/JN)

  16. Analysis methods for meso- and macroporous silicon etching baths

    PubMed Central

    2012-01-01

    Analysis methods for electrochemical etching baths consisting of various concentrations of hydrofluoric acid (HF) and an additional organic surface wetting agent are presented. These electrolytes are used for the formation of meso- and macroporous silicon. Monitoring the etching bath composition requires at least one method each for the determination of the HF concentration and the organic content of the bath. However, it is a precondition that the analysis equipment withstands the aggressive HF. Titration and a fluoride ion-selective electrode are used for the determination of the HF and a cuvette test method for the analysis of the organic content, respectively. The most suitable analysis method is identified depending on the components in the electrolyte with the focus on capability of resistance against the aggressive HF. PMID:22805742

  17. Department of Mechanical Engineering University of Bath, Bath BA2 7AY, UK

    E-print Network

    Burton, Geoffrey R.

    Department of Mechanical Engineering University of Bath, Bath BA2 7AY, UK Email: ptmc@bath, at that time, the School of Engineering in the Bath University of Technology. Forty years later and Design at the University of Bath. When the Centre was founded, the University was based in Ashley Down

  18. Pulling bubbles from a bath

    E-print Network

    Kao, Justin C. T.

    Deposition of bubbles on a wall withdrawn from a liquid bath is a phenomenon observed in many everyday situations—the foam lacing left behind in an emptied glass of beer, for instance. It is also of importance to the many ...

  19. Organization and Analysis of Data from the Qweak Experiment

    NASA Astrophysics Data System (ADS)

    Cargill, Dan; Spayde, Damon

    2013-04-01

    The Qweak experiment, which was conducted at the Thomas Jefferson National Accelerator Facility in a collaboration consisting of over twenty institutions, measured the small parity violating asymmetry occurring in elastic e-p scattering at low four-momentum transfer. This asymmetry will be used to calculate a precise value for the proton's weak charge. The Standard Model firmly predicts this weak charge based on the running of the weak mixing angle from the Z0 pole (where it is anchored by precise measurements) down to low energies. Through testing this prediction the Qweak experiment hopes to either constrain or reveal possible new physics beyond the Standard Model. Because of the small size of the predicted asymmetry and the precise nature of the measurement, over 2000 hours of data were taken. In order to help organize and store this data, a database has been implemented containing averages over sets of this data. It must be organized in such a way as to allow the quick and easy retrieval of data by collaborators with minimal knowledge of the database language. Tools for aggregating and expanding parts of this database as well as data analysis will be discussed.

  20. Retrieval and allocation of organs for transplantation: the Michigan experience.

    PubMed

    Rosenberg, J C; Beyersdorf, T M; Derbyshire, N; Fortunato, R; Manley, G; Williams, T

    1993-01-01

    The Organ Procurement Agency of Michigan (OPAM) is now in its twenty-third year of service to the transplant community in Michigan. From a beginning with one coordinator in 1971, it now employs 53 individuals, including 8 laboratory technologists for its own on-site histocompatibility laboratory, a dozen procurement coordinators stationed throughout the state, 6 organ placement coordinators in the main office, 6 screening coordinators who provide around-the-clock coverage at the office, a tissue recovery section, as well as additional finance, education, and administrative support staff. This chapter outlines the history and growth in organ recoveries of the organization. More importantly, the chapter also analyzes the Michigan experience regarding racial distribution of kidneys. While African-Americans comprise 14% of the general population of the state, they comprise 40% of the waiting kidney recipients and only 26% of the actual recipients. Depending upon blood type, average waiting time for a kidney for African-Americans can be up to 4 months longer than for Whites. The analysis attributes this variance primarily to the allocation methodology for kidney distribution, which is largely driven by antigen matching and secondarily to the generally greater frequency and higher degree of blood sensitization among African-Americans, which causes a substantially higher frequency of positive-crossmatch results between potential donor and recipient. The authors conclude that changes in the present allocation system could be made to achieve greater equity for African-American patients, without removing the advantages inherent in transplanting kidneys with closely matched antigens. PMID:7918166

  1. Dissipative Landau-Zener transitions of a qubit: Bath-specific and universal behavior

    SciTech Connect

    Saito, Keiji [Department of Physics, Graduate School of Science, University of Tokyo, Tokyo 113-0033 (Japan); Department of Physics, Graduate School of Science, 2 CREST, JST, 4-1-8 Honcho Kawaguchi, Saitama 332-0012 (Japan); Wubs, Martijn; Kohler, Sigmund; Haenggi, Peter [Institut fuer Physik, Universitaet Augsburg, Universitaetsstrasse 1, D-86135 Augsburg (Germany); Kayanuma, Yosuke [Department of Mathematical Science, Graduate School of Engineering, Osaka Prefecture University, Sakai 599-8531 (Japan)

    2007-06-01

    We study Landau-Zener transitions in a qubit coupled to a bath at zero temperature. A general formula that is applicable to models with a nondegenerate ground state is derived. We calculate exact transition probabilities for a qubit coupled to either a bosonic or a spin bath. The nature of the baths and the qubit-bath coupling is reflected in the transition probabilities. For diagonal coupling, when the bath causes energy fluctuations of the diabatic qubit states but no transitions between them, the transition probability coincides with the standard Landau-Zener probability of an isolated qubit. This result is universal as it does not depend on the specific type of bath. For pure off-diagonal coupling, by contrast, the tunneling probability is sensitive to the coupling strength. We discuss the relevance of our results for experiments on molecular nanomagnets, in circuit QED, and for the fast-pulse readout of superconducting phase qubits.

  2. Conditions Entrance Bath 1 Bath 2 Kitchen Bdrm. 1 Bdrm. 2 Bdrm. 3 Bdrm. 4

    E-print Network

    Conditions Entrance Living Room Dining Room Bath 1 Bath 2 Kitchen Bdrm. 1 Bdrm. 2 Bdrm. 3 Bdrm. 4-In/Move-Out Checklist Toilet, Sink, and Shower Ceiling & Walls Windows Doors Electricity Appliances PAGE 1 #12;Conditions Entrance Living Room Dining Room Bath 1 Bath 2 Kitchen Bdrm. 1 Bdrm. 2 Bdrm. 3 Bdrm. 4 Clean

  3. 16 CFR 1215.2 - Requirements for infant bath seats.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 2013-01-01 false Requirements for infant bath seats. 1215.2 Section 1215.2...SAFETY ACT REGULATIONS SAFETY STANDARD FOR INFANT BATH SEATS § 1215.2 Requirements for infant bath seats. Each infant bath seat...

  4. Heat-Bath Cooling of Spins in Two Amino Acids

    E-print Network

    Yuval Elias; Haggai Gilboa; Tal Mor; Yossi Weinstein

    2011-10-26

    Heat-bath cooling is a component of practicable algorithmic cooling of spins, an approach which might be useful for in vivo 13C spectroscopy, in particular for prolonged metabolic processes where substrates that are hyperpolarized ex-vivo are not effective. We applied heat-bath cooling to 1,2-13C2-amino acids, using the alpha protons to shift entropy from selected carbons to the environment. For glutamate and glycine, both carbons were cooled by about 2.5-fold, and in other experiments the polarization of C1 nearly doubled while all other spins had equilibrium polarization, indicating reduction in total entropy. The effect of adding Magnevist, a gadolinium contrast agent, on heat-bath cooling of glutamate was investigated.

  5. Photometric determination of aluminum sulfate in a zinc-aluminum-containing bath in viscose manufacturing

    Microsoft Academic Search

    I. P. Smirnov

    1990-01-01

    A procecure has been developed for the photometric determination of the aluminum sulfate content of a mixed zinc-aluminum-containing precipitation bath in viscose manufacturing, using the bifunctional organic reagent chromazo-BRZ.

  6. The ORGANIC Experiment on EXPOSE-R on the ISS: A Space Exposure Experiment

    NASA Astrophysics Data System (ADS)

    Bryson, Kathryn; Peeters, Z.; Salama, F.; Foing, B.; Ehrenfreund, P.; Ricco, A.; Jessberger, E. K.; Bischoff, A.; Breitfellner, M.; Schmidt, W.; Robert, F.

    2013-06-01

    Aromatic networks are among the most abundant organic material in space. PAHs and fullerenes have been identified in meteorites and are thought to be among the carriers for numerous astronomical absorption and emission features. Thin films of selected PAHs and fullerenes have been subjected to the low Earth orbit environment as part of the ORGANIC experiment on the multi-user facility EXPOSE-R onboard the ISS. The ORGANIC experiment monitored the chemical evolution, survival, destruction, and chemical modification of the samples. EXPOSE-R was mounted on the outside of the ISS from March 10, 2009 to January 21, 2011. The samples were returned to Earth and inspected in spring 2011. The 682-day period outside the ISS provided continuous exposure to the cosmic-, solar-, and trapped-particle radiation background and >2500 h of unshadowed solar illumination. All trays carry both solar-irradiation-exposed and dark samples shielded from the UV photons, enabling discrimination between the effects of exposure to solar photons and cosmic rays. The samples were analyzed before exposure to the space environment with UV-VIS spectroscopy. Ground truth monitoring of additional sample carriers was performed through UV-VIS spectroscopy at regular intervals at NASA Ames Research Center. During the exposure on the ISS, 2 control sample carriers were exposed with a slight time shift in a planetary simulation chamber at the Microgravity User Support Center at DLR. Vacuum, UV radiation, and temperature fluctuations are simulated according to the telemetry data measured during flight. The spectroscopic measurements of these two carriers have been performed together with the returned flight samples. We report on the scientific experiment, the details of the ground control analysis, and preliminary flight sample results.

  7. Bathing

    MedlinePLUS

    ... much as possible. This protects his or her dignity and helps the person feel more in control. ... other resources: • • • Read “Caring for a Person with Alzheimer’s Disease”: www.nia. nih.gov/alzheimers/publication/ caring-person- ...

  8. The development of the Space Environment Viability of Organics (SEVO) experiment aboard the Organism\\/Organic Exposure to Orbital Stresses (O\\/OREOS) satellite

    Microsoft Academic Search

    Nathan E. Bramall; Richard Quinn; Andrew Mattioda; Kathryn Bryson; Julie D. Chittenden; Amanda Cook; Cindy Taylor; Giovanni Minelli; Pascale Ehrenfreund; Antonio J. Ricco; David Squires; Orlando Santos; Charles Friedericks; David Landis; Nykola C. Jones; Farid Salama; Louis J. Allamandola; Søren V. Hoffmann

    The Space Environment Viability of Organics (SEVO) experiment is one of two scientific payloads aboard the triple-cube satellite Organism\\/ORganic Exposure to Orbital Stresses (O\\/OREOS). O\\/OREOS is the first technology demonstration mission of the NASA Astrobiology Small Payloads Program. The 1-kg, 1000-cm3 SEVO cube is investigating the chemical evolution of organic materials in interstellar space and planetary environments by exposing organic

  9. Slag foaming in bath smelting

    Microsoft Academic Search

    R. Jiang; R. J. Fruehan

    1991-01-01

    Slag foaming measurements in terms of the foaming index (?) were conducted on bath smelting-type slags (CaO-SiO2-FeO, CaO-SiO2-MgO-Al2O3-FeO) at 1773 K. It was found that the slag foam stability decreases with increasing FeO (FeO > 2 pct) content and basicity.\\u000a For the slag system (CaO-SiO2-FeO), no stable foam was observed at very low FeO content (<2 pct). As pct FeO

  10. Organic weed management in vegetables: Research, experiences, and opportunities

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic farmers in a national survey ranked weed management as their greatest research need for organic crop production. Scientists from the Agriculture Research Service and Oklahoma State University have combined their efforts to conduct not only organic weed control research, but research involvi...

  11. The Separation and Identification of Two Unknown Solid Organic Compounds: An Experiment for the Sophomore Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Feist, Patty L.

    2004-01-01

    Segregation and recognition of two unfamiliar concrete organic compounds are achieved through microscale flash chromatography and spectroscopy plus melting point verifications respectively. This inexpensive and harmless microscale experiment for sophomore students ensures exercise in chromatographic and spectroscopic methods.

  12. 21 CFR 890.5110 - Paraffin bath.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5110 Paraffin bath. (a) Identification. A paraffin...

  13. 21 CFR 890.5110 - Paraffin bath.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5110 Paraffin bath. (a) Identification. A paraffin...

  14. 21 CFR 890.5110 - Paraffin bath.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5110 Paraffin bath. (a) Identification. A paraffin...

  15. The Photochemical Isomerization of Maleic to Fumaric Acid: An Undergraduate Organic Chemistry Experiment.

    ERIC Educational Resources Information Center

    Castro, Albert J.; And Others

    1983-01-01

    Describes an undergraduate organic chemistry experiment on the photochemical isomerization of maleic to fumaric acid. Background information, chemical reactions involved, and experimental procedures are included. (JN)

  16. 33 CFR 334.45 - Kennebec River, Bath Iron Works Shipyard, naval restricted area, Bath, Maine.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Shipyard, naval restricted area, Bath, Maine. 334.45 Section 334.45 Navigation...Shipyard, naval restricted area, Bath, Maine. (a) The area. The waters within a coffin shaped...the Supervisor of Shipbuilding, USN Bath Maine or his authorized representative...

  17. University of Bath -Student Records & Examinations Office -Student numbers -1 Dec 1997 University of Bath

    E-print Network

    Burton, Geoffrey R.

    University of Bath - Student Records & Examinations Office - Student numbers - 1 Dec 1997 University of Bath Student Records & Examinations Office 1 Dec 97 student numbers: explanatory notes & routes, or in association with, the University of Bath in the academic year 1997-98 at the snapshot date of 1 December 1997

  18. University of Bath -Student Records & Examinations Office -Student numbers -1 Dec 1995 University of Bath

    E-print Network

    Burton, Geoffrey R.

    University of Bath - Student Records & Examinations Office - Student numbers - 1 Dec 1995 University of Bath Student Records & Examinations Office 1 Dec 1995 student numbers: explanatory notes, or in association with, the University of Bath in the academic year 1995-96 at the snapshot date of 1 December

  19. University of Bath -Student Records & Examinations Office -Student numbers -1 Dec 1994 University of Bath

    E-print Network

    Burton, Geoffrey R.

    University of Bath - Student Records & Examinations Office - Student numbers - 1 Dec 1994 University of Bath Student Records & Examinations Office 1 Dec 1994 student numbers: explanatory notes, or in association with, the University of Bath in the academic year 1994-95 at the snapshot date of 1 December

  20. University of Bath -Student Records & Examinations Office -Student numbers -1 Dec 1996 University of Bath

    E-print Network

    Burton, Geoffrey R.

    University of Bath - Student Records & Examinations Office - Student numbers - 1 Dec 1996 University of Bath Student Records & Examinations Office 1 Dec 1996 student numbers: explanatory notes, or in association with, the University of Bath in the academic year 1996-97 at the snapshot date of 1 December

  1. IMMIGRANTS' EXPERIENCES IN AMERICA: TOWARD UNDERSTANDING ORGANIZED CRIME

    Microsoft Academic Search

    Charles B. A. Ubah

    Using the emergence of Sicilian Mafia in the United States of America as the focal condition, this article investigates why the emergence of organized crime in the United State of America is widely misunderstood. The author aims to provide a renewed theoretical analysis of the social problem. Central to this analysis are two contradictory perspectives on the emergence of organized

  2. Could Communication Form Impact Organizations' Experience with Diversity?

    ERIC Educational Resources Information Center

    Grimes, Diane Susan; Richard, Orlando C.

    2003-01-01

    Argues that cultural diversity can be advantageous or detrimental for organizations depending on organization members' communication. Introduces three forms of communication (ethnocentric, modernistic and cosmopolitan) explored by W. Barnett Pearce, each of which differs in deeply held assumptions. Overviews the implications of cosmopolitan…

  3. University of Bath Opus Repository Policies v1.0

    E-print Network

    McCusker, Guy

    University of Bath Opus Repository Policies v1.0 The latest version of this document is available from the University of Bath Opus website at http://opus.bath.ac.uk The University of Bath Opus & data set held 1. This is an institutional or departmental repository. 2. University of Bath Opus

  4. Pseudomonas folliculitis in Arabian baths.

    PubMed

    Molina-Leyva, Alejandro; Ruiz-Ruigomez, Maria

    2013-07-01

    A 35-year-old man presented with a painful cutaneous skin eruption that was localized on the upper trunk. He stated that the previous weekend he had attended an Arabian bath. The physical examination revealed multiple hair follicle-centered papulopustules surrounded by an erythematous halo. A clinical diagnosis of pseudomonas folliculitis was made and treatment was prescribed. Afterwards Pseudomonas aeruginosa was isolated from a pustule culture. Pseudomonas folliculitis is a bacterial infection of the hair follicles. The most common reservoirs include facilities with hot water and complex piping systems that are difficult to clean, such as hot tubs and bathtubs. Despite adequate or high chlorine levels, Pseudomonas aeruginosa can grow within a biofilm. PMID:24010505

  5. New system for bathing bedridden patients

    NASA Technical Reports Server (NTRS)

    Greenleaf, J. E.; Staley, R. A.; Payne, P. A.

    1973-01-01

    Multihead shower facility can be used with minimal patient handling. Waterproof curtain allows patient to bathe with his head out of shower. He can move completely inside shower to wash his face and hair. Main advantage of shower system is time saved in giving bath.

  6. Tautomerization of Acetylacetone Enol. A Physical Organic Experiment in Kinetics and Thermodynamics.

    ERIC Educational Resources Information Center

    Spyridis, Greg T.; Meany, J. E.

    1988-01-01

    Describes a physical organic experiment in thermodynamics and kinetics for undergraduate courses in organic chemistry, biochemistry, or physical chemistry. Details background information, solution preparations, equipment and methods, and the suggested experiments such as determination of general-base-catalytic coefficients and the Bronsted…

  7. Taxonomic Organization Scaffolds Young Children's Learning from Storybooks: A Design Experiment

    ERIC Educational Resources Information Center

    Kaefer, Tanya; Pinkham, Ashley M.; Neuman, Susan B.

    2010-01-01

    The purpose of this design experiment was to research, test and iteratively design a set of taxonomically-organized storybooks that served to scaffold young children's word learning and concept development. Specifically, Phase 1 of the design experiment asked: (1) What are the effects of taxonomic organization on children's ability to acquire…

  8. Anaerobic degradation of organic waste: An experience in mathematical modeling

    Microsoft Academic Search

    V. A. Vavilin

    2010-01-01

    Some key aspects of organic waste degradation were analyzed by means of mathematical models using data obtained in laboratory\\u000a reactors. It was shown that an essential condition of effective methane production is the balance between sequential and parallel\\u000a stages not resulting in accumulation of intermediate products that are potential inhibitors of the process. Decreased initial\\u000a concentration of organic matter (dilution)

  9. PERFORMANCE OF ORGANIC GRAIN CROPPING SYSTEMS IN LONG-TERM EXPERIMENTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Organic farming and conventional no-tillage farming systems share many of the same benefits from protecting and improving soils. A review of recent results from long-term systems experiments in the mid-Atlantic region of the U.S.A. demonstrates that organic cropping systems with organic amendments ...

  10. Analysis of Analgesic Mixtures: An Organic Chemistry Experiment.

    ERIC Educational Resources Information Center

    Martin, Ned H.

    1981-01-01

    Describes an experiment to analyze commercial analgesic preparations (pain relievers) by silica gel thin layer chromatography, followed by preparative (thick) layer chromatographic separation and spectroscopic analysis. Key difference from similar experiments is that students are responsible for devising suitable solvent systems for the thin layer…

  11. Team Science: Organizing Classroom Experiments That Develop Group Skills.

    ERIC Educational Resources Information Center

    Coffin, Marilyn

    This book contains classroom experiments designed to promote group skills. Each lesson has 4 parts: a 3-minute set-up; 5-minute warm-up, 25-minute experiment, and 5-minute clean-up. During each part, each member of the group is responsible for performing a specific task. Included are 34 labs that cover a range of topics: observations, physical…

  12. Achieving "Organic Compositionality" through Self-organization: Reviews on Brain-Inspired Robotics Experiments

    E-print Network

    Tani, Jun

    Achieving "Organic Compositionality" through Self-organization: Reviews on Brain-Inspired Robotics"from the Japanese Ministry of Education, Culture, Sports, Science and Technology. Requests for reprints should, robot, prediction, hierarchy, parietal cortex, premotor cortex, mirror neurons, dynamical systems

  13. 21 CFR 740.17 - Foaming detergent bath products.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 2013-04-01 false Foaming detergent bath products. 740.17 Section...Statements § 740.17 Foaming detergent bath products. (a) For the purpose of this section, a foaming detergent bath product is any product...

  14. Organic synthesis by quench reactions. [in prebiotic simulation experiment

    NASA Technical Reports Server (NTRS)

    Park, W. K.; Hochstim, A. R.; Ponnamperuma, C.

    1975-01-01

    Study of the effects of chemical quench reactions on the formation of organic compounds at a water surface under simulated primordial earth conditions. A mixture of gaseous methane and ammonia over a water surface was exposed to an arc discharge between an electrode and the water surface, generating reactive species. Various organic molecules were formed by a subsequent quenching of these species generated on the water surface. The effects of these water-surface quench reactions were assessed by comparing the amounts of synthesized molecules to the amounts which formed during the discharge of an arc above the water level. It is concluded that the quench (or wet) discharge led to faster rates of reactions, higher-molecular-weight organic compounds, and one-order-of-magnitude larger yields than the dry discharge.

  15. Will recently proposed experiments be able to demonstrate quantum behavior of entire living organisms?

    E-print Network

    C. L. Herzenberg

    2009-12-12

    Recently proposed experiments consider creating and observing the quantum superposition of small living organisms. Those proposed experiments are examined here for feasibility on the basis of results of earlier studies identifying a boundary separating obligatory classical behavior from quantum behavior. It appears that the proposed experiments may be expected to succeed for the case of viruses, but most probably fail for the case of the appreciably larger organisms that are also considered.

  16. Balamuthia mandrillaris therapeutic mud bath in Jamaica.

    PubMed

    Todd, C D; Reyes-Batlle, M; Piñero, J E; Martínez-Carretero, E; Valladares, B; Lindo, J F; Lorenzo-Morales, J

    2014-10-22

    SUMMARY Balamuthia mandrillaris is an emerging cause of encephalitis in humans. The transmission dynamics are poorly understood due to the high fatality rate and the sporadic nature of cases. Seventy-two soil samples were collected from beaches and the banks of lagoons, rivers, ponds, mineral springs and streams from across Jamaica and assayed for the presence of B. mandrillaris. Seventy-nine sites were sampled and the mitochondrial 16S rDNA gene of B. mandrillaris was amplified and sequenced to confirm the presence of the amoeba. One isolate of B. mandrillaris was recovered from soil from mineral spring which hosts an informal therapeutic mud bath business. Although B. mandrillaris is less frequently isolated from soil than other free-living amoebae, rubbing mud containing the organism onto the skin increases the likelihood of exposure and infection. This first report on the isolation of B. mandrillaris in the Caribbean and its presence in soil where human contact is likely warrants further investigation using serological methods to elucidate exposure patterns. PMID:25335452

  17. Identifying risks in healthcare organization: the Tuscany region experience

    Microsoft Academic Search

    S. Albolino; M. Fioranib

    The paper introduces the experience of the Tuscany Region in building an informative system able to identify risks inside the healthcare local units. It also discusses the related implications on patient safety initiatives. The system basically relies on two main sources of information about clinical risks and accidents inside the hospitals: patient claims and clinicians voluntary reports. Patient claims coming

  18. Experimental bath engineering for quantitative studies of quantum control

    E-print Network

    A. Soare; H. Ball; D. Hayes; X. Zhen; M. C. Jarratt; J. Sastrawan; H. Uys; M. J. Biercuk

    2014-04-08

    We develop and demonstrate a technique to engineer universal unitary baths in quantum systems. Using the correspondence between unitary decoherence due to ambient environmental noise and errors in a control system for quantum bits, we show how a wide variety of relevant classical error models may be realized through In-Phase/Quadrature modulation on a vector signal generator producing a resonant carrier signal. We demonstrate our approach through high-bandwidth modulation of the 12.6 GHz carrier appropriate for trapped $^{171}$Yb$^{+}$ ions. Experiments demonstrate the reduction of coherent lifetime in the system in the presence of an engineered bath, with the observed $T_{2}$ scaling as predicted by a quantitative model described herein. These techniques form the basis of a toolkit for quantitative tests of quantum control protocols, helping experimentalists characterize the performance of their quantum coherent systems.

  19. Protective coating for salt-bath brazing

    NASA Technical Reports Server (NTRS)

    Francisco, A. C.; Gyorgak, C. A.

    1971-01-01

    Ceramic coating, consisting of graphite, enameler's clay, and algin binder, applied to materials prior to salt bath brazing facilitates brazing process and results in superior joints. Alternate coating materials and their various proportions are given.

  20. Synthetic drugs: bath salts and spice.

    PubMed

    Randolph, Susan A

    2014-02-01

    Occupational and environmental health nurses should be aware of bath salts and spice as drugs of abuse that have increased in recent years and educate workers and management about their harmful effects. PMID:24512723

  1. Drops bouncing on a vibrating bath

    E-print Network

    Bush, John W. M.

    We present the results of a combined experimental and theoretical investigation of millimetric droplets bouncing on a vertically vibrating fluid bath. We first characterize the system experimentally, deducing the dependence ...

  2. Our plumbing, ourselves : a public bath house

    E-print Network

    Merceret, Honor

    1993-01-01

    Cleansing for being well Cleansing for well being. This thesis will consider: --how developments in plumbing and sewage and their related fixtures, kitchens and baths, parallel cultural changes throughout history. Though ...

  3. Mephedrone ("bath salt") pharmacology: insights from invertebrates.

    PubMed

    Ramoz, L; Lodi, S; Bhatt, P; Reitz, A B; Tallarida, C; Tallarida, R J; Raffa, R B; Rawls, S M

    2012-04-19

    Psychoactive bath salts (also called meph, drone, meow meow, m-CAT, bounce, bubbles, mad cow, etc.) contain a substance called mephedrone (4-methylcathinone) that may share psychostimulant properties with amphetamine and cocaine. However, there are only limited studies of the neuropharmacological profile of mephedrone. The present study used an established invertebrate (planarian) assay to test the hypothesis that acute and repeated mephedrone exposure produces psychostimulant-like behavioral effects. Acute mephedrone administration (50-1000 ?M) produced stereotyped movements that were attenuated by a dopamine receptor antagonist (SCH 23390) (0.3 ?M). Spontaneous discontinuation of mephedrone exposure (1, 10 ?M) (60 min) resulted in an abstinence-induced withdrawal response (i.e. reduced motility). In place conditioning experiments, planarians in which mephedrone (100, 500 ?M) was paired with the non-preferred environment during conditioning displayed a shift in preference upon subsequent testing. These results suggest that mephedrone produces three behavioral effects associated with psychostimulant drugs, namely dopamine-sensitive stereotyped movements, abstinence-induced withdrawal, and environmental place conditioning. PMID:22300981

  4. Mephedrone (‘bath salt’) pharmacology: insights from invertebrates

    PubMed Central

    Ramoz, Leda; Lodi, Sabah; Bhatt, Parth; Reitz, Allen B.; Tallarida, Chris; Tallarida, Ronald J.; Raffa, Robert B.; Rawls, Scott M.

    2014-01-01

    Psychoactive bath salts (also called meph, drone, meow meow, m-CAT, bounce, bubbles, mad cow, etc.) contain a substance called mephedrone (4-methylcathinone) that may share psychostimulant properties with amphetamine and cocaine. However, there are only limited studies of the neuropharmacological profile of mephedrone. The present study used an established invertebrate (planarian) assay to test the hypothesis that acute and repeated mephedrone exposure produces psychostimulant-like behavioral effects. Acute mephedrone administration (50 – 1000 µM) produced stereotyped movements that were attenuated by a dopamine receptor antagonist (SCH 23390) (0.3 µM). Spontaneous discontinuation of mephedrone exposure (1, 10 µM) (60 min) resulted in an abstinence-induced withdrawal response (i.e., reduced motility). In place conditioning experiments, planarians in which mephedrone (100, 500 µM) was paired with the non-preferred environment during conditioning displayed a shift in preference upon subsequent testing. These results suggest that mephedrone produces three behavioral effects associated with psychostimulant drugs, namely dopamine-sensitive stereotyped movements, abstinence-induced withdrawal, and environmental place conditioning. PMID:22300981

  5. Reaction rate in a heat bath

    E-print Network

    M Jacob; P V Landshoff

    1992-04-23

    We show in detail how the presence of a heat bath of photons effectively gives charged particles in the final state of a decay process a temperature-dependent mass, and changes the effective strength of the force responsible for the decay. At low temperature, gauge invariance causes both these effects to be largely cancelled by absorption of photons from the heat bath and by stimulated emission into it, but at high temperature the temperature-dependent mass is the dominant feature.

  6. A Continuous 4He Refrigerator for Use in a Superfluid Helium Bath

    SciTech Connect

    Wang, Suwen; Avaloff, D.; Nissen, J. A.; Stricker, D. A.; Lipa, J. A. [Hansen Experimental Physics Laboratory, Stanford University, Stanford, California (United States)

    2006-09-07

    In cryogenic applications in space, the base temperature, Tmin of the helium bath in the dewar is typically determined by the design of the porous plug and the associated plumbing. For certain experiments, the required operating temperature of the instrument is lower than the bath temperature. In the laboratory, temperatures below 1.2 K require very large pumps or the use of 3He systems. We have demonstrated a modified 4He refrigerator with a continuous fill from a superfluid helium bath with a base temperature more than 0.5 K below the bath temperature. We describe the operation as well as the mechanism of such a refrigerator. For operation in space the refrigerator would need to be equipped with a porous plug to retain the fluid.

  7. A Cost-Effective Two-Part Experiment for Teaching Introductory Organic Chemistry Techniques

    ERIC Educational Resources Information Center

    Sadek, Christopher M.; Brown, Brenna A.; Wan, Hayley

    2011-01-01

    This two-part laboratory experiment is designed to be a cost-effective method for teaching basic organic laboratory techniques (recrystallization, thin-layer chromatography, column chromatography, vacuum filtration, and melting point determination) to large classes of introductory organic chemistry students. Students are exposed to different…

  8. Agent-Based Modeling and Computational Experiments in Industrial Organization: Growing Firms and Industries in silico

    E-print Network

    Tesfatsion, Leigh

    -depth survey of computational models in indus- trial organization. Rather, it is to position the agentAgent-Based Modeling and Computational Experiments in Industrial Organization: Growing Firms the need for, the mechanics of, and some potential application of agent-based modeling and computational

  9. Vibrio natriegens: A Rapidly Growing Micro-Organism Ideally Suited for Class Experiments

    ERIC Educational Resources Information Center

    Mullenger, L.; Gill, Nijole R.

    1973-01-01

    Describes five microbiological experiments using the marine organism Vibrio natriegens. This organism is highly suitable for laboratory work because it is non-pathogenic and grows extremely rapidly, having the distinction of the lowest mean generation time yet recorded (9.8 minutes). (JR)

  10. Experimental Heat-Bath Cooling of Spins

    E-print Network

    Gilles Brassard; Yuval Elias; José M. Fernandez; Haggai Gilboa; Jonathan A. Jones; Tal Mor; Yossi Weinstein; Li Xiao

    2014-04-28

    Algorithmic cooling (AC) is a method to purify quantum systems, such as ensembles of nuclear spins, or cold atoms in an optical lattice. When applied to spins, AC produces ensembles of highly polarized spins, which enhance the signal strength in nuclear magnetic resonance (NMR). According to this cooling approach, spin-half nuclei in a constant magnetic field are considered as bits, or more precisely, quantum bits, in a known probability distribution. Algorithmic steps on these bits are then translated into specially designed NMR pulse sequences using common NMR quantum computation tools. The $algorithmic$ cooling of spins is achieved by alternately combining reversible, entropy-preserving manipulations (borrowed from data compression algorithms) with $selective$ $reset$, the transfer of entropy from selected spins to the environment. In theory, applying algorithmic cooling to sufficiently large spin systems may produce polarizations far beyond the limits due to conservation of Shannon entropy. Here, only selective reset steps are performed, hence we prefer to call this process "heat-bath" cooling, rather than algorithmic cooling. We experimentally implement here two consecutive steps of selective reset that transfer entropy from two selected spins to the environment. We performed such cooling experiments with commercially-available labeled molecules, on standard liquid-state NMR spectrometers. Our experiments yielded polarizations that $bypass$ $Shannon's$ $entropy$-$conservation$ $bound$, so that the entire spin-system was cooled. This paper was initially submitted in 2005, first to Science and then to PNAS, and includes additional results from subsequent years (e.g. for resubmission in 2007). The Postscriptum includes more details.

  11. The Recovery and Identification of Flammable Liquids in Suspected Arsons: An Undergraduate Organic Experiment

    ERIC Educational Resources Information Center

    Blackledge, Robert D.

    1974-01-01

    Describes an experiment which can be used to test for the use of accelerants in the origin of a fire. Involves distillation and gas liquid chromatography to identify the accelerants, thus combining two experiments ordinarily included in the beginning organic laboratory. (SLH)

  12. Examination of a Reaction Mechanism by Polarimetry: An Experiment for the Undergraduate Organic Chemistry Laboratory

    NASA Astrophysics Data System (ADS)

    Mosher, Michael D.; Kelly, Chad O.; Mosher, Melvyn W.

    1996-06-01

    An undergraduate Organic chemistry laboratory experiment involving the use of polarimetry to determine a reaction mechanism is described. The experiment has been shown to be successful with chiral mandelic acid and POCl3 and with chiral lactic acid and HBr. The substitution mechanisms of these reactions proceed with 1% and 38% SN2 character respectively.

  13. Using appropriate strategies to improve teaching and learning in organic chemistry and organic chemical experiment courses

    Microsoft Academic Search

    Yingjie Lin; Zaiqun Liu

    2003-01-01

    In China, higher education needs to be reformed profoundly. This kind of reform must focus on making learning more efficient and improving educational practice. This is a challenge for us. Like other courses, the practice of teaching organic chemistry requires change in order to improve teaching and learning. This may require a rethink of our approach to education. In this

  14. The organ donor family members' perception of stressful situations during the organ donation experience.

    PubMed

    Pelletier, M

    1992-01-01

    The purpose of this study was to determine what the individual organ/tissue donor family members appraised as most stressful during the anticipation, confrontation and post-confrontation stages of the organ-donation process. The Lazarus and Folkman stress and coping theory guided the development and interpretation of the study. Family members who had lost a loved one suddenly and consented to donation in 1988 were interviewed. Data were analysed by means of content analysis. Findings showed that family members appraised different types of stressful situations during the three stages. The most frequently reported stressful situations centred around the threat of losing a loved one, confirmation of brain death, failure of the health professionals to identify the loved one as a potential donor and to approach the family regarding organ donation, and adjusting to the many changes associated with the loss. Significantly, five families requested donation, while two readily consented when approached. All family members reported that organ donation had helped with their grief. The findings of this study contribute to the development of knowledge required to guide nursing interventions to provide sensitive care to donors and their families. PMID:1537995

  15. 33 CFR 165.104 - Safety Zone: Vessel Launches, Bath Iron Works, Kennebec River, Bath, Maine.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Bath Iron Works, Kennebec River, Bath, Maine. (a) Location...all waters of the Kennebec River within a 150-yard radius...deployed position in the Kennebec River, and while launching or recovering...Port will notify the maritime community of periods during which...

  16. 33 CFR 165.104 - Safety Zone: Vessel Launches, Bath Iron Works, Kennebec River, Bath, Maine.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Bath Iron Works, Kennebec River, Bath, Maine. (a) Location...all waters of the Kennebec River within a 150-yard radius...deployed position in the Kennebec River, and while launching or recovering...Port will notify the maritime community of periods during which...

  17. 33 CFR 165.104 - Safety Zone: Vessel Launches, Bath Iron Works, Kennebec River, Bath, Maine.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Bath Iron Works, Kennebec River, Bath, Maine. (a) Location...all waters of the Kennebec River within a 150-yard radius...deployed position in the Kennebec River, and while launching or recovering...Port will notify the maritime community of periods during which...

  18. 33 CFR 165.104 - Safety Zone: Vessel Launches, Bath Iron Works, Kennebec River, Bath, Maine.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Bath Iron Works, Kennebec River, Bath, Maine. (a) Location...all waters of the Kennebec River within a 150-yard radius...deployed position in the Kennebec River, and while launching or recovering...Port will notify the maritime community of periods during which...

  19. Biogeochemistry of two types of permeable reactive barriers, organic carbon and iron-bearing organic carbon for mine drainage treatment: Column experiments

    Microsoft Academic Search

    Qiang Guo; David W. Blowes

    2009-01-01

    Permeable reactive barriers (PRBs) are an alternative technology to treat mine drainage containing sulfate and heavy metals. Two column experiments were conducted to assess the suitability of an organic carbon (OC) based reactive mixture and an Fe0-bearing organic carbon (FeOC) based reactive mixture, under controlled groundwater flow conditions. The organic carbon mixture contains about 30% (volume) organic carbon (composted leaf

  20. Analysis Of The Returned Samples From A Space Exposure Experiment: The ORGANIC Experiment on EXPOSE-R on the ISS

    NASA Astrophysics Data System (ADS)

    Bryson, Kathryn; Peeters, Zan; Salama, Farid; Foing, Bernard; Ehrenfreund, Pascale; Elsaesser, Andreas; Ricco, Antonio; Jessberger, Elmar K; Schmidt, Werner; Robert, François

    2014-06-01

    The ORGANIC experiment on the multi-user facility EXPOSE-R on the International Space Station investigated the chemical evolution, survival, destruction, and chemical modification of PAHs and fullerenes in space. Aromatic networks are among the most abundant organic material in space. PAHs and fullerenes have been identified in meteorites and are thought to be among the carriers for numerous astronomical absorption and emission features.Thin films of selected PAHs and fullerenes have been subjected to the low Earth orbit environment as part of the ORGANIC experiment.EXPOSE-R with its experiment inserts was mounted on the outside of the ISS for 682 days starting in 2009. The samples were returned to Earth and inspected in spring 2011. The period outside the ISS provided continuous exposure to the cosmic-, solar-, and trapped-particle radiation background and >2500 h of unshadowed solar illumination. All trays carry both solar-irradiation-exposed and dark samples shielded from the UV photons, enabling discrimination between the effects of exposure to solar photons and cosmic rays. The samples were analyzed before exposure to the space environment with UV-VIS and IR spectroscopy. Ground truth monitoring of additional sample carriers was performed through UV-VIS spectroscopy at regular intervals at NASA ARC (Bryson et al. 2011, Adv. Space Res. 48, 1980). The UV-VIS and IR spectroscopic measurements were collected for the returned flight samples.We report on the scientific experiment, the details of the ground control analysis, and returned flight sample results. We discuss how extended space exposure experiments allow to enhance our knowledge on the evolution of organic compounds in space.

  1. Experience with an organ procurement organization-based non-directed living kidney donation programme.

    PubMed

    Mark, Paula J; Baker, Kristie; Aguayo, Cecile; Sorensen, John B

    2006-01-01

    The organ procurement organization (OPO)-based non-directed living kidney donation programme was developed to decrease wait times for kidney transplants, and to meet the community's desire for altruistic living donation. Community awareness was encouraged through information about non-directed living kidney donation on the state donor registry Web site, and through the media. The OPO received all inquiries and responded with phone calls, e-mails, printed information, medical/social history questionnaires, interviews, and referrals to the transplant centres. Kidneys were allocated according to the United Network for Organ Sharing (UNOS) wait list for the evaluating transplant centre. Between March 2002 and 23 September 2005, there were 608 inquiries to the OPO about non-directed living kidney donation. In 41 months, 20 transplants occurred with kidneys from non-directed donors. The donor registry and OPO-sponsored publicity led to 578 of the 608 inquiries and 15 of the 20 transplants. OPO screening saved transplant centre resources by ruling out 523 inquiries, referring 76 to transplant centres for complete evaluations. Optional donor/recipient meetings appeared to be beneficial to those participating. OPO-based non-directed living donor programmes can be effective and efficient. Standardization of evaluation, allocation, and follow-up will allow for better data collection and more widespread implementation. PMID:16842517

  2. Pyrolysis-GCMS Analysis of Solid Organic Products from Catalytic Fischer-Tropsch Synthesis Experiments

    NASA Technical Reports Server (NTRS)

    Locke, Darren R.; Yazzie, Cyriah A.; Burton, Aaron S.; Niles, Paul B.; Johnson, Natasha M.

    2015-01-01

    Abiotic synthesis of complex organic compounds in the early solar nebula that formed our solar system is hypothesized to occur via a Fischer-Tropsch type (FTT) synthesis involving the reaction of hydrogen and carbon monoxide gases over metal and metal oxide catalysts. In general, at low temperatures (less than 200 C), FTT synthesis is expected to form abundant alkane compounds while at higher temperatures (greater than 200 C) it is expected to product lesser amounts of n-alkanes and greater amounts of alkene, alcohol, and polycyclic aromatic hydrocarbons (PAHs). Experiments utilizing a closed-gas circulation system to study the effects of FTT reaction temperature, catalysts, and number of experimental cycles on the resulting solid insoluble organic products are being performed in the laboratory at NASA Goddard Space Flight Center. These experiments aim to determine whether or not FTT reactions on grain surfaces in the protosolar nebula could be the source of the insoluble organic matter observed in meteorites. The resulting solid organic products are being analyzed at NASA Johnson Space Center by pyrolysis gas chromatography mass spectrometry (PY-GCMS). PY-GCMS yields the types and distribution of organic compounds released from the insoluble organic matter generated from the FTT reactions. Previously, exploratory work utilizing PY-GCMS to characterize the deposited organic materials from these reactions has been reported. Presented here are new organic analyses using magnetite catalyst to produce solid insoluble organic FTT products with varying reaction temperatures and number of experimental cycles.

  3. The development of the Space Environment Viability of Organics (SEVO) experiment aboard the Organism/Organic Exposure to Orbital Stresses (O/OREOS) satellite

    NASA Astrophysics Data System (ADS)

    Bramall, Nathan E.; Quinn, Richard; Mattioda, Andrew; Bryson, Kathryn; Chittenden, Julie D.; Cook, Amanda; Taylor, Cindy; Minelli, Giovanni; Ehrenfreund, Pascale; Ricco, Antonio J.; Squires, David; Santos, Orlando; Friedericks, Charles; Landis, David; Jones, Nykola C.; Salama, Farid; Allamandola, Louis J.; Hoffmann, Søren V.

    2012-01-01

    The Space Environment Viability of Organics (SEVO) experiment is one of two scientific payloads aboard the triple-cube satellite Organism/ORganic Exposure to Orbital Stresses (O/OREOS). O/OREOS is the first technology demonstration mission of the NASA Astrobiology Small Payloads Program. The 1-kg, 1000-cm3 SEVO cube is investigating the chemical evolution of organic materials in interstellar space and planetary environments by exposing organic molecules under controlled conditions directly to the low-Earth orbit (LEO) particle and electromagnetic radiation environment. O/OREOS was launched on November 19, 2010 into a 650-km, 72°-inclination orbit and has a nominal operational lifetime of six months. Four classes of organic compounds, namely an amino acid, a quinone, a polycyclic aromatic hydrocarbon (PAH), and a metallo-porphyrin are being studied. Initial reaction conditions were established by hermetically sealing the thin-film organic samples in self-contained micro-environments. Chemical changes in the samples caused by direct exposure to LEO radiation and by interactions with the irradiated microenvironments are monitored in situ by ultraviolet/visible/near-infrared (UV/VIS/NIR) absorption spectroscopy using a novel compact fixed-grating CCD spectrometer with the Sun as its light source. The goals of the O/OREOS mission include: (1) demonstrating key small satellite technologies that can enable future low-cost astrobiology experiments, (2) deploying a miniature UV/VIS/NIR spectrometer suitable for in-situ astrobiology and other scientific investigations, (3) testing the capability to establish a variety of experimental reaction conditions to enable the study of astrobiological processes on small satellites, and (4) measuring the chemical evolution of organic molecules in LEO under conditions that can be extrapolated to interstellar and planetary environments. In this paper, the science and technology development of the SEVO instrument payload and its measurements are described.

  4. Quantum bath refrigeration towards absolute zero: unattainability principle challenged

    E-print Network

    Michal Kolá?; David Gelbwaser-Klimovsky; Robert Alicki; Gershon Kurizki

    2012-08-05

    A minimal model of a quantum refrigerator (QR), i.e. a periodically phase-flipped two-level system permanently coupled to a finite-capacity bath (cold bath) and an infinite heat dump (hot bath), is introduced and used to investigate the cooling of the cold bath towards the absolute zero (T=0). Remarkably, the temperature scaling of the cold-bath cooling rate reveals that it does not vanish as T->0 for certain realistic quantized baths, e.g. phonons in strongly disordered media (fractons) or quantized spin-waves in ferromagnets (magnons). This result challenges Nernst's third-law formulation known as the unattainability principle.

  5. Simulating trends in soil organic carbon in long-term experiments using the CANDY model

    Microsoft Academic Search

    U. Franko; G. J. Crocker; P. R. Grace; J. Klír; M. Körschens; P. R. Poulton; D. D. Richter

    1997-01-01

    CANDY (CArbon and Nitrogen DYnamics) is a simulation system based on long-term experiments of organic matter turnover and nitrogen dynamics at Bad Lauchstädt, Germany. Key driving variables are soil physical properties, meteorological data and management information. The main application of the CANDY model is the calculation of short-term dynamics of nitrogen transformation and long-term dynamics of organic matter turnover in

  6. Vibro-acoustics of organ pipes--revisiting the Miller experiment (L).

    PubMed

    Gautier, F; Nief, G; Gilbert, J; Dalmont, J P

    2012-01-01

    A century ago, Science published a spectacular experimental study on the physics of organ pipes. Dayton C. Miller observed experimentally that the sound produced by an organ pipe can depend on the vibration of its walls, in addition to its internal geometry and the interaction between the air jet and the labium. The Miller experiment has been repeated and an interpretation is now proposed in terms of vibroacoustic coupling mechanisms between walls and internal fluid, which can lead to "pathological" behavior. PMID:22280696

  7. Failure of the Shockley-Haynes Mobility Experiment with organic semiconducting materials

    E-print Network

    Boehme, Hollis Clyde

    1961-01-01

    FAILURE OF THE SHOCKLEY-dAYNES MOB1LITY EXPERIMENT WITH ORGANIC SENICOHDUCTIHG NATERIALS A Thesis HOLLIS CLYDE BOEHNE Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment of tbe... requirements for the degree of NASTER OF SCIENCE August 1961 Major Subjectt Physics PAILUHE OP THE SHOCKLEY-HAYNES MO31LITY EXPERIMENT I/ITH ORGANIC SEMICONDUCTING MATERIALS s nl A rA X W R i 0 0 g A Thesis HOLLIS CLYDE BOEHME Approved...

  8. Seeking organic compounds on Mars : in situ analysis of organic compounds by Gas Chromatography-Mass Spectrometry on MOMA experiment

    NASA Astrophysics Data System (ADS)

    Buch, A.; Freissinet, C.; Sternberg, R.; Pinnick, V.; Szopa, C.; Coll, P. J.; Rodier, C.; Garnier, C.; Steininger, H.; Moma Team

    2010-12-01

    The search for signs of past or present life is one of the primary goals of future Mars exploratory missions. The Mars Organic Molecule Analyzer (MOMA) experiment of the ExoMars mission (set to launch 2016-2018) is a joint venture by the European Space Agency and NASA to develop a sensitive detector for organics on Mars. MOMA will be one of the main analytical instruments aboard the ExoMars Rover aimed at characterizing possible “signs-of-life molecules” in the Martian environment such as amino acids, carboxylic acids, nucleobases or polycyclic aromatic hydrocarbons (PAHs). With the aim to separate and detect organic compounds from Martian soil, the French MOMA team has built a gas chromatograph able to work in standalone mode by using a TCD detector. The gas chromatograph can also be coupled with an ion trap mass spectrometer developed by the US MOMA team. Moreover, a GC-MS compatible sample processing system (SPS) allowing the extraction and the chemical transformation of the organic compounds from the soil, that fits within space flight conditions, has also been developed. The sample processing is performed in an oven, dedicated to the MOMA experiment containing the solid sample (50-100mg). The internal temperature of oven can be ranged from 20 to 1000 °C which allows for pyrolysis, thermochemolysis or derivatization. The organic extraction step is achieved by using thermodesorption in the range of 100 to 300°C for 0.5 to 5 min. Then, the chemical derivatization and/or thermochemolysis of the extracted compounds is performed directly on the soil with a mixture of MTBSTFA-DMF, TMAH or DMF-DMA solution when enantiomeric separation is required. By decreasing the polarity of the target molecules, this step allows for their volatilization at a temperature below 250°C without any chemical degradation. Once derivatized, the volatile target molecules are trapped in a cold chemical trap and promptly desorbed into the gas chromatograph coupled to the mass spectrometer. Preliminary tests, performed on several analogue soils such as Atacama soil, with the MOMA SPS-GC/MS experiment demonstrated the capability to detect organic compounds such as amino and carboxylic acids with sensitivities below the ppm level.

  9. Photovoltaic windows by chemical bath deposition

    Microsoft Academic Search

    J. Herrero; M. T. Gutiérrez; C. Guillén; J. M. Doña; M. A. Mart??nez; A. M. Chaparro; R. Bayón

    2000-01-01

    The paper presents a scope of different studies performed on thin-film materials, commonly used as window layers in polycrystalline thin-film solar cells, and prepared by the chemical bath deposition (CBD) method. The presented studies try to offer an approach to some key points of the chemical preparation that are directly related to the final quality and properties of the films.

  10. Reaction rates in a heat bath

    Microsoft Academic Search

    M. Jacob; P. V. Landshoff

    1992-01-01

    The presence of a heat bath of photons gives an extra effective mass to charged particles and changes the effective strength of the interaction responsible for a decay. All effects are calculated and it is shown that, in order alphaT2, the decay rate is not modified.

  11. Reaction rate in a heat bath

    Microsoft Academic Search

    Maurice René Michel Jacob; Peter V Landshoff

    1992-01-01

    We show in detail how the presence of a heat bath of photons effectively gives charged particles in the final state of a decay process a temperature-dependent mass, and changes the effective strength of the force responsible for the decay. At low temperature, gauge invariance causes both these effects to be largely cancelled by absorption of photons from the heat

  12. Soil Organic Matter Dynamics in the Rothamsted Long-term Experiments

    NASA Astrophysics Data System (ADS)

    MacDonald, A.; Poulton, P.

    2009-04-01

    Soil science research at Rothamsted dates from 1843 when John Bennet Lawes and Joseph Henry Gilbert started the first of a series of what became long-term field experiments. The main object of these experiments was to examine the effect of inorganic and organic fertilisers and manures on crop yield and soil fertility. These "Classical Field Experiments" included studies on winter wheat (Broadbalk 1843), spring barley (Hoos Barley 1852) and permanent grassland (Park Grass 1856). Additional experiments were established in the 20th century to examine the value of ley-arable cropping, including the Highfield and Fosters Ley-arable experiments (1948) and the Woburn Ley-arable experiment (1938). More recently, the effects of incorporating organic manures and cereal straw have been examined. Early results quickly showed the benefits of inorganic N and P fertilisers on crop production, but the effects of contrasting land uses and management practices on soil properties emerged more slowly. Measurements of soil organic carbon (C) and nitrogen (N) in soils taken at intervals from the long-term experiments indicate that the rate of soil organic matter (SOM) accumulation is controlled largely by the balance between the rate of organic matter inputs and its oxidation rate, and that these are strongly influenced by land use and management, soil texture (especially clay content) and climate. A recent examination of soil organic C data from two long-term grassland experiments in the UK (including Park Grass) indicates that any changes observed in soil organic C under long-term grasslands over the past 40 years are more likely to be due to changes in land use and management rather than climate change. Data from the Rothamsted Long-term experiments have been used to develop and test biogeochemical models of C and N dynamics. In particular, the Roth-C model has successfully simulated soil C dynamics in the long-term experiments at Rothamsted and elsewhere. This model uses several organic matter pools, including decomposable and resistant plant material, soil microbial biomass, humified organic matter and inert organic matter and was one of the 31 models included in the GCTE SOMNET network. The Rothamsted Long-term Experiments together with their archived samples and data have proven especially useful for examining the impact of land use and management on soil organic matter dynamics. They continue to yield important information and are an increasingly valuable experimental resource for today's scientists. Whilst their future long-term uses cannot be predicted, provided they are well maintained, the application of new scientific techniques to examine both fresh and archived samples will continue to provide information of environmental and ecological significance to future generations. Rothamsted Research receives grant-aided support from the Biotechnology and Biological Sciences Research Council and additional support from the Lawes Agricultural Trust. Presentation of this work forms part of the ANAEE EC design study (www.anaee.com).

  13. Psychoactive “bath salts”: not so soothing

    PubMed Central

    Baumann, Michael H.; Partilla, John S.; Lehner, Kurt R.

    2012-01-01

    Recently there has been a dramatic rise in the abuse of so-called “bath salts” products that are purchased as legal alternatives to illicit drugs like cocaine and 3,4-methylenedioxymethamphetamine (MDMA). Baths salts contain one or more synthetic derivatives of the naturally-occurring stimulant cathinone. Low doses of bath salts produce euphoria and increase alertness, but high doses or chronic use can cause serious adverse effects such as hallucinations, delirium, hyperthermia and tachycardia. Owing to the risks posed by bath salts, the governments of many countries have made certain cathinones illegal, namely: 4-methylmethcathinone (mephedrone), 3,4-methylenedioxymethcathinone (methylone) and 3,4-methylenedioxypyrovalerone (MDPV). Similar to other psychomotor stimulants, synthetic cathinones target plasma membrane transporters for dopamine (i.e., DAT), norepinephrine (i.e., NET) and serotonin (i.e, SERT). Mephedrone and methylone act as non-selective transporter substrates, thereby stimulating non-exocytotic release of dopamine, norepinephrine and serotonin. By contrast, MDPV acts as a potent blocker at DAT and NET, with little effect at SERT. Administration of mephedrone or methylone to rats increases extracellular concentrations of dopamine and serotonin in the brain, analogous to the effects of MDMA. Not surprisingly, synthetic cathinones elicit locomotor activation in rodents. Stimulation of dopamine transmission by synthetic cathinones predicts a high potential for addiction and may underlie clinical adverse effects. As popular synthetic cathinones are rendered illegal, new replacement cathinones are appearing in the marketplace. More research on the pharmacology and toxicology of abused cathinones is needed to inform public health policy and develop strategies for treating medical consequence of bath salts abuse. PMID:23178799

  14. General view, Belair Bath and Tennis Club, Belair at Bowie, ...

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

    General view, Belair Bath and Tennis Club, Belair at Bowie, Maryland, looking west. - Belair Bath and Tennis Club, Southwest corner of Belair Drive and Tulip Grove Drive, Bowie, Prince George's County, MD

  15. 30 CFR 75.1712 - Bath houses and toilet facilities.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Resources 1 2014-07-01 2014-07-01 false Bath houses and toilet facilities. 75.1712 Section 75.1712 Mineral...STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1712 Bath houses and toilet facilities. [Statutory Provisions]...

  16. 30 CFR 75.1712 - Bath houses and toilet facilities.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Resources 1 2013-07-01 2013-07-01 false Bath houses and toilet facilities. 75.1712 Section 75.1712 Mineral...STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1712 Bath houses and toilet facilities. [Statutory Provisions]...

  17. 30 CFR 75.1712 - Bath houses and toilet facilities.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Resources 1 2012-07-01 2012-07-01 false Bath houses and toilet facilities. 75.1712 Section 75.1712 Mineral...STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1712 Bath houses and toilet facilities. [Statutory Provisions]...

  18. 30 CFR 75.1712 - Bath houses and toilet facilities.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Resources 1 2011-07-01 2011-07-01 false Bath houses and toilet facilities. 75.1712 Section 75.1712 Mineral...STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1712 Bath houses and toilet facilities. [Statutory Provisions]...

  19. 30 CFR 75.1712 - Bath houses and toilet facilities.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Resources 1 2010-07-01 2010-07-01 false Bath houses and toilet facilities. 75.1712 Section 75.1712 Mineral...STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1712 Bath houses and toilet facilities. [Statutory Provisions]...

  20. Laboratory Experiment Investigating the Impact of Ocean Acidification on Calcareous Organisms

    ERIC Educational Resources Information Center

    Perera, Alokya P.; Bopegedera, A. M. R. P.

    2014-01-01

    The increase in ocean acidity since preindustrial times may have deleterious consequences for marine organisms, particularly those with calcareous structures. We present a laboratory experiment to investigate this impact with general, introductory, environmental, and nonmajors chemistry students. For simplicity and homogeneity, calcite was…

  1. Cocrystal Controlled Solid-State Synthesis: A Green Chemistry Experiment for Undergraduate Organic Chemistry

    ERIC Educational Resources Information Center

    Cheney, Miranda L.; Zaworotko, Michael J.; Beaton, Steve; Singer, Robert D.

    2008-01-01

    Green chemistry has become an important area of concern for all chemists from practitioners in the pharmaceutical industry to professors and the students they teach and is now being incorporated into lectures of general and organic chemistry courses. However, there are relatively few green chemistry experiments that are easily incorporated into…

  2. An NMR Study of Isotope Effect on Keto-Enol Tautomerization: A Physical Organic Chemistry Experiment

    ERIC Educational Resources Information Center

    Atkinson, D.; Chechik, V.

    2004-01-01

    Isotope substitution often affects the rate of an organic reaction and can be used to reveal the underlying mechanism. A series of experiments that use (super 1)H NMR to determine primary and secondary isotope effects, activation parameters, and the regioselectivity of butanone enolization are described.

  3. The Synthesis of a Cockroach Pheromone: An Experiment for the Second-Year Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Feist, Patty L.

    2008-01-01

    This experiment describes the synthesis of gentisyl quinone isovalerate, or blattellaquinone, a sex pheromone of the German cockroach that was isolated and identified in 2005. The synthesis is appropriate for the second semester of a second-year organic chemistry laboratory course. It can be completed in two, three-hour laboratory periods and uses…

  4. Solvent-Free Wittig Reaction: A Green Organic Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Leung, Sam H.; Angel, Stephen A.

    2004-01-01

    Some Wittig reactions can be carried out by grinding the reactants in a mortar with a pestle for about 20 minutes, as per investigation. A laboratory experiment involving a solvent-free Wittig reaction that can be completed in a three-hour sophomore organic chemistry laboratory class period, are developed.

  5. Usnic Acid and the Intramolecular Hydrogen Bond: A Computational Experiment for the Organic Laboratory

    ERIC Educational Resources Information Center

    Green, Thomas K.; Lane, Charles A.

    2006-01-01

    A computational experiment is described for the organic chemistry laboratory that allows students to estimate the relative strengths of the intramolecular hydrogen bonds of usnic and isousnic acids, two related lichen secondary metabolites. Students first extract and purify usnic acid from common lichens and obtain [superscript 1]H NMR and IR…

  6. Ring-Closing Metathesis: An Advanced Guided-Inquiry Experiment for the Organic Laboratory

    ERIC Educational Resources Information Center

    Schepmann, Hala G.; Mynderse, Michelle

    2010-01-01

    The design and implementation of an advanced guided-inquiry experiment for the organic laboratory is described. Grubbs's second-generation catalyst is used to effect the ring-closing metathesis of diethyl diallylmalonate. The reaction is carried out under an inert atmosphere at room temperature and monitored by argentic TLC. The crude reaction is…

  7. The Photochemical Synthesis, Kinetics, and Reactions of Nitrosomethane Dimer: A Physical-Organic Experiment.

    ERIC Educational Resources Information Center

    Kozubek, H.; And Others

    1982-01-01

    Provides background information procedures, and results for the photochemical synthesis and reactions of nitrosomethane dimer. The experiments described have shown a high degree of reliability with student use and are suggested to illustrate some problems of physical and organic photochemistry. (Author/JN)

  8. 16 CFR 1215.2 - Requirements for infant bath seats.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...similar bathing enclosure and that provides support, at a minimum, to the front and back of a seated infant during bathing by a caregiver. This does not include products that are designed or intended to retain water for bathing. (ii) [Reserved]...

  9. Processing A Printed Wiring Board By Single Bath Electrodeposition

    DOEpatents

    Meltzer, Michael P. (Oakland, CA); Steffani, Christopher P. (Livermore, CA); Gonfiotti, Ray A. (Livermore, CA)

    2003-04-15

    A method of processing a printed wiring board by single bath electrodeposition. Initial processing steps are implemented on the printed wiring board. Copper is plated on the printed wiring board from a bath containing nickel and copper. Nickel is plated on the printed wiring board from the bath containing nickel and copper and final processing steps are implemented on the printed wiring board.

  10. University of Bath BITE SIZE GUIDE TO ETHICS IN RESEARCH

    E-print Network

    Burton, Geoffrey R.

    University of Bath BITE SIZE GUIDE TO ETHICS IN RESEARCH We must apply the highest ethical in the following places: University's Institutional Code of Ethics (http://www.bath.ac.uk/internal/ethics/committee/docs/institutionalcodeofethics.pdf) University's Code of Good Practice in Research (http://www.bath.ac.uk/opp

  11. 75 FR 51177 - Safety Standard for Infant Bath Seats; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-19

    ...COMMISSION 16 CFR Part 1215 Safety Standard for Infant Bath Seats; Correction AGENCY: Consumer...The document established a standard for infant bath seats by incorporating by reference...final rule establishing a standard for infant bath seats by incorporating by...

  12. Facebook as a medium for promoting statement of intent for organ donation: 5-years of experience.

    PubMed

    Brzezi?ski, Micha?; Klikowicz, Pawe?

    2015-01-01

    The number of potential registered organ donors does not cover the actual demand in most developed countries. Therefore, methods increasing awareness and interest in organ donation, including modern tools of social marketing, are being researched worldwide. The aim of this paper is to present our 5-year experiences with a Facebook networking campaign - the Dawca.pl Club. The mission of the campaign is to raise awareness and educate Polish society on tissue, cell, and organ transplants, to increase public acceptance for transplants as a treatment method, and to increase the number of voluntary donors signing consents for organ donation. The project is based on the idea of creating a community promoting transplantation, focused around the Dawca.pl Club. At present the club has over 48 000 registered members - people who declared willingness to donate their organs after death. We present a description of members of this social networking service, the possibilities of using it to promote transplants and organ donation, and the efficacy of selected schemes for creating and publishing content on Facebook. The example of Dawca.pl shows that 2-way relations, spread over time, are required for social media to effectively engage and exert influence in a chosen sphere of public health and medicine. Unfortunately, at this time it is difficult to assess how such campaigns, apart from raising social awareness and acceptance, will affect the number of transplantations of organs from living and deceased donors. PMID:25761524

  13. Experimental implementation of heat-bath algorithmic cooling using solid-state nuclear magnetic resonance

    E-print Network

    Jonathan Baugh; Osama Moussa; Colm A. Ryan; Ashwin Nayak; Raymond Laflamme

    2005-12-02

    We report here the experimental realization of multi-step cooling of a quantum system via heat-bath algorithmic cooling. The experiment was carried out using nuclear magnetic resonance (NMR) of a solid-state ensemble three-qubit system.

  14. TeamBath Support Programme Application process 1. TeamBath support programme application forms emailed to priority sport coaches.

    E-print Network

    Burton, Geoffrey R.

    / Department Sport Coach or NGB Coach Gym / Facility Access o Free Gym Membership Sports Science Support / Facility Access o Free Gym Membership Fitness classes o Free access to fitness classes Sports Science.mcmillan@bath.ac.uk, Department of Sports Development and Recreation, Founders Hall, University of Bath, Claverton Down, Bath, BA2

  15. Molten salt bath circulation design for an electrolytic cell

    DOEpatents

    Dawless, R.K.; LaCamera, A.F.; Troup, R.L.; Ray, S.P.; Hosler, R.B.

    1999-08-17

    An electrolytic cell for reduction of a metal oxide to a metal and oxygen has an inert anode and an upwardly angled roof covering the inert mode. The angled roof diverts oxygen bubbles into an upcomer channel, thereby agitating a molten salt bath in the upcomer channel and improving dissolution of a metal oxide in the molten salt bath. The molten salt bath has a lower velocity adjacent the inert anode in order to minimize corrosion by substances in the bath. A particularly preferred cell produces aluminum by electrolysis of alumina in a molten salt bath containing aluminum fluoride and sodium fluoride. 4 figs.

  16. Molten salt bath circulation design for an electrolytic cell

    DOEpatents

    Dawless, Robert K. (Monroeville, PA); LaCamera, Alfred F. (Trafford, PA); Troup, R. Lee (Murrysville, PA); Ray, Siba P. (Murrysville, PA); Hosler, Robert B. (Sarver, PA)

    1999-01-01

    An electrolytic cell for reduction of a metal oxide to a metal and oxygen has an inert anode and an upwardly angled roof covering the inert mode. The angled roof diverts oxygen bubbles into an upcomer channel, thereby agitating a molten salt bath in the upcomer channel and improving dissolution of a metal oxide in the molten salt bath. The molten salt bath has a lower velocity adjacent the inert anode in order to minimize corrosion by substances in the bath. A particularly preferred cell produces aluminum by electrolysis of alumina in a molten salt bath containing aluminum fluoride and sodium fluoride.

  17. Growth experiment of organic metal crystal in low gravity (M-21)

    NASA Technical Reports Server (NTRS)

    Anzai, Hiroyuki

    1993-01-01

    The purpose of this experiment is to grow large, high-quality single crystals of the organic metal (TMTTF-TCNQ) by the diffusion method without thermal fluctuation due to convection and gravitational sedimentation, and to evaluate the difference in properties between such crystals grown in low gravity and the ones obtained on Earth. The expected results may fix several physical properties of TMTTF-TCNQ, lead to the discovery of new phenomena, and enable us to analyze diffusion processes in a precise way. The result will contribute to the development of research on organic metals and, generally, on crystal growth.

  18. Utilizing ARC EMCS Seedling Cassettes as Highly Versatile Miniature Growth Chambers for Model Organism Experiments

    NASA Technical Reports Server (NTRS)

    Freeman, John L.; Steele, Marianne K.; Sun, Gwo-Shing; Heathcote, David; Reinsch, S.; DeSimone, Julia C.; Myers, Zachary A.

    2014-01-01

    The aim of our ground testing was to demonstrate the capability of safely putting specific model organisms into dehydrated stasis, and to later rehydrate and successfully grow them inside flight proven ARC EMCS seedling cassettes. The ARC EMCS seedling cassettes were originally developed to support seedling growth during space flight. The seeds are attached to a solid substrate, launched dry, and then rehydrated in a small volume of media on orbit to initiate the experiment. We hypothesized that the same seedling cassettes should be capable of acting as culture chambers for a wide range of organisms with minimal or no modification. The ability to safely preserve live organisms in a dehydrated state allows for on orbit experiments to be conducted at the best time for crew operations and more importantly provides a tightly controlled physiologically relevant growth experiment with specific environmental parameters. Thus, we performed a series of ground tests that involved growing the organisms, preparing them for dehydration on gridded Polyether Sulfone (PES) membranes, dry storage at ambient temperatures for varying periods of time, followed by rehydration. Inside the culture cassettes, the PES membranes were mounted above blotters containing dehydrated growth media. These were mounted on stainless steel bases and sealed with plastic covers that have permeable membrane covered ports for gas exchange. The results showed we were able to demonstrate acceptable normal growth of C.elegans (nematodes), E.coli (bacteria), S.cerevisiae (yeast), Polytrichum (moss) spores and protonemata, C.thalictroides (fern), D.discoideum (amoeba), and H.dujardini (tardigrades). All organisms showed acceptable growth and rehydration in both petri dishes and culture cassettes initially, and after various time lengths of dehydration. At the end of on orbit ISS European Modular Cultivation System experiments the cassettes could be frozen at ultra-low temperatures, refrigerated, or chemically preserved before being returned to Earth for analyses. Our results suggest that with protocol modifications and future verification testing we can utilize the versatile EMCS to conduct tightly controlled experiments inside our culture cassettes for a wide variety of organisms. These physiological experiments would be designed to answer questions at the molecular level about the specific stress responses of space flight.

  19. Role of Organic Acids in Bioformation of Kaolinite: Results of Laboratory Experiments

    NASA Astrophysics Data System (ADS)

    Bontognali, T. R. R.; Vasconcelos, C.; McKenzie, J. A.

    2012-04-01

    Clay minerals and other solid silica phases have a broad distribution in the geological record and greatly affect fundamental physicochemical properties of sedimentary rocks, including porosity. An increasing number of studies suggests that microbial activity and microbially produced organic acids might play an important role in authigenic clay mineral formation, at low temperatures and under neutral pH conditions. In particular, early laboratory experiments (Linares and Huertas, 1971) reported the precipitation of kaolinite in solutions of SiO2 and Al2O3 with different molar ratios SiO2/Al2O3, together with fulvic acid (a non-characterized mixture of many different acids containing carboxyl and phenolate groups) that was extracted from peat soil. Despite many attempts, these experiments could not be reproduced until recently. Fiore et al. (2011) hypothesized that the non-sterile fulvic acid might have contained microbes that participated in the formation of kaolinite. Using solutions saturated with Si and Al and containing oxalate and/or mixed microbial culture extracted from peat-moss soil, they performed incubation experiments, which produced kaolinite exclusively in solutions containing oxalate and microbes. We proposed to test the role of specific organic acids for kaolinite formation, conducting laboratory experiments at 25?C, with solutions of sodium silicate, aluminum chloride and various organic compounds (i.e. EDTA, citric acid, succinic acid and oxalic acid). Specific organic acids may stabilize aluminum in octahedral coordination positions, which is crucial for the initial nucleation step. In our experiments, a poorly crystalline mineral that is possibly a kaolinite precursor formed exclusively in the presence of succinic acid. In experiments with other organic compounds, no incorporation of Al was observed, and amorphous silica was the only precipitated phase. In natural environments, succinic acid is produced by a large variety of microbes as an intermediate product of the tricarboxylic acid cycle. Our results demonstrate, for the first time, that the formation of a specific clay mineral (proto-kaolinite) occurs in the presence of a specific organic compound (succinic acid). This implies that microbial species capable of excreting succinate among their EPS may promote authigenic kaolinite formation at low temperature and neutral pH. This biological degradation process might play a crucial role for the formation of authigenic kaolinite, which is a widespread clay mineral in sedimentary environments. Fiore, S., Dumontet, S., Huertas, F.J., and Pasquale, V., 2011. Bacteria-induced crystallization of kaolinite. Applied Clay Science, 53:566-571. Linares, J., and Huertas, F., 1971. Kaolinite: Synthesis at room temperature. Science 171: 896-897.

  20. Brownian ratchet in a thermal bath driven by Coulomb friction.

    PubMed

    Gnoli, Andrea; Petri, Alberto; Dalton, Fergal; Pontuale, Giorgio; Gradenigo, Giacomo; Sarracino, Alessandro; Puglisi, Andrea

    2013-03-22

    The rectification of unbiased fluctuations, also known as the ratchet effect, is normally obtained under statistical nonequilibrium conditions. Here we propose a new ratchet mechanism where a thermal bath solicits the random rotation of an asymmetric wheel, which is also subject to Coulomb friction due to solid-on-solid contacts. Numerical simulations and analytical calculations demonstrate a net drift induced by friction. If the thermal bath is replaced by a granular gas, the well-known granular ratchet effect also intervenes, becoming dominant at high collision rates. For our chosen wheel shape the granular effect acts in the opposite direction with respect to the friction-induced torque, resulting in the inversion of the ratchet direction as the collision rate increases. We have realized a new granular ratchet experiment where both these ratchet effects are observed, as well as the predicted inversion at their crossover. Our discovery paves the way to the realization of micro and submicrometer Brownian motors in an equilibrium fluid, based purely upon nanofriction. PMID:25166785

  1. Brownian Ratchet in a Thermal Bath Driven by Coulomb Friction

    NASA Astrophysics Data System (ADS)

    Gnoli, Andrea; Petri, Alberto; Dalton, Fergal; Pontuale, Giorgio; Gradenigo, Giacomo; Sarracino, Alessandro; Puglisi, Andrea

    2013-03-01

    The rectification of unbiased fluctuations, also known as the ratchet effect, is normally obtained under statistical nonequilibrium conditions. Here we propose a new ratchet mechanism where a thermal bath solicits the random rotation of an asymmetric wheel, which is also subject to Coulomb friction due to solid-on-solid contacts. Numerical simulations and analytical calculations demonstrate a net drift induced by friction. If the thermal bath is replaced by a granular gas, the well-known granular ratchet effect also intervenes, becoming dominant at high collision rates. For our chosen wheel shape the granular effect acts in the opposite direction with respect to the friction-induced torque, resulting in the inversion of the ratchet direction as the collision rate increases. We have realized a new granular ratchet experiment where both these ratchet effects are observed, as well as the predicted inversion at their crossover. Our discovery paves the way to the realization of micro and submicrometer Brownian motors in an equilibrium fluid, based purely upon nanofriction.

  2. Study of Martian Organic Molecules Irradiation and Evolution: The Momie Experiment

    NASA Astrophysics Data System (ADS)

    Coll, Patrice; Stalport, F.; Szopa, C.; Cottin, H.

    2007-12-01

    The life on Mars remains an open question despite the Viking landers results and the ALH84001 possible terrestrial contamination. However recent data of Mars Express orbiter and the twin rovers Spirit and Opportunity seem show different proofs of a past environment with liquid water and mild temperatures favorable for life. Among the biomarkers we seek, the organic molecules are primordial because they are necessary to the origin of life as we know it. However, these molecules (except methane recently discovered) have never been detected on Mars by the in situ analyzes of the Viking landers. A key question is to know if organic molecules are indeed present, in which concentration and under which form. Indeed, even if endogenous organic molecules were never synthesized, those brought by exogenous sources, like interplanetary dust, should be present in detectable amount. Moreover, the track of the endogenous organic molecules should not be dropped out because these molecules are able to resist over periods of several billion years without being degraded. It thus appears that organic molecules could be present at the surface of Mars, even if they have significant chances to undergo a partial or total chemical evolution. Within the framework of a search for organic molecules by present or future space experiments , we are developing the MOMIE project (Martian Organic Material Irradiation and Evolution) in order to determine how the organic species evolve on the Martian surface. We thus propose to implement this type of research with the assistance of an experimental setup designed for the study of the behavior of organic molecules under conditions simulating as close as possible conditions of Mars surface, and plan to present at 39th DPS our first results.

  3. Measurement of Smooth Muscle Function in the Isolated Tissue Bath-applications to Pharmacology Research

    PubMed Central

    Jespersen, Brian; Tykocki, Nathan R.; Watts, Stephanie W.; Cobbett, Peter J.

    2015-01-01

    Isolated tissue bath assays are a classical pharmacological tool for evaluating concentration-response relationships in a myriad of contractile tissues. While this technique has been implemented for over 100 years, the versatility, simplicity and reproducibility of this assay helps it to remain an indispensable tool for pharmacologists and physiologists alike. Tissue bath systems are available in a wide array of shapes and sizes, allowing a scientist to evaluate samples as small as murine mesenteric arteries and as large as porcine ileum – if not larger. Central to the isolated tissue bath assay is the ability to measure concentration-dependent changes to isometric contraction, and how the efficacy and potency of contractile agonists can be manipulated by increasing concentrations of antagonists or inhibitors. Even though the general principles remain relatively similar, recent technological advances allow even more versatility to the tissue bath assay by incorporating computer-based data recording and analysis software. This video will demonstrate the function of the isolated tissue bath to measure the isometric contraction of an isolated smooth muscle (in this case rat thoracic aorta rings), and share the types of knowledge that can be created with this technique. Included are detailed descriptions of aortic tissue dissection and preparation, placement of aortic rings in the tissue bath and proper tissue equilibration prior to experimentation, tests of tissue viability, experimental design and implementation, and data quantitation. Aorta will be connected to isometric force transducers, the data from which will be captured using a commercially available analog-to-digital converter and bridge amplifier specifically designed for use in these experiments. The accompanying software to this system will be used to visualize the experiment and analyze captured data. PMID:25650585

  4. Measurement of Smooth Muscle Function in the Isolated Tissue Bath-applications to Pharmacology Research.

    PubMed

    Jespersen, Brian; Tykocki, Nathan R; Watts, Stephanie W; Cobbett, Peter J

    2015-01-01

    Isolated tissue bath assays are a classical pharmacological tool for evaluating concentration-response relationships in a myriad of contractile tissues. While this technique has been implemented for over 100 years, the versatility, simplicity and reproducibility of this assay helps it to remain an indispensable tool for pharmacologists and physiologists alike. Tissue bath systems are available in a wide array of shapes and sizes, allowing a scientist to evaluate samples as small as murine mesenteric arteries and as large as porcine ileum - if not larger. Central to the isolated tissue bath assay is the ability to measure concentration-dependent changes to isometric contraction, and how the efficacy and potency of contractile agonists can be manipulated by increasing concentrations of antagonists or inhibitors. Even though the general principles remain relatively similar, recent technological advances allow even more versatility to the tissue bath assay by incorporating computer-based data recording and analysis software. This video will demonstrate the function of the isolated tissue bath to measure the isometric contraction of an isolated smooth muscle (in this case rat thoracic aorta rings), and share the types of knowledge that can be created with this technique. Included are detailed descriptions of aortic tissue dissection and preparation, placement of aortic rings in the tissue bath and proper tissue equilibration prior to experimentation, tests of tissue viability, experimental design and implementation, and data quantitation. Aorta will be connected to isometric force transducers, the data from which will be captured using a commercially available analog-to-digital converter and bridge amplifier specifically designed for use in these experiments. The accompanying software to this system will be used to visualize the experiment and analyze captured data. PMID:25650585

  5. University of Bath Opus Notice & Takedown Policy V1.2

    E-print Network

    McCusker, Guy

    University of Bath Opus Notice & Takedown Policy V1.2 The latest version of this document is available from the University of Bath Opus website at http://opus.bath.ac.uk The Bath Opus Maximising the impact of your research opus.bath.ac.uk Notice & Takedown Policy The University of Bath Online

  6. Stable Carbon Isotopic Signatures of Abiotic Organics from Hydrothermal Synthesis Experiments

    NASA Technical Reports Server (NTRS)

    Stern, Jennifer C.; Summers, David P.; Kubo, Mike; Yassar, Saima

    2006-01-01

    Stable carbon isotopes can be powerful biogeochemical markers in the study of life's origins. Biogenic carbon fixation produces organics that are depleted in C-13 by about -20 to -30%0. Less attention has been paid to the isotopic signatures of abiotic processes. The possibility of abiotic processes producing organics with morphologies and isotopic signatures in the biogenic range has been at the center of recent debate over the Earth's earliest microfossils. The abiotic synthesis of organic compounds in hydrothermal environments is one possible source of endogenous organic matter to the prebiotic earth. Simulated hydrothermal settings have been shown to synthesize, among other things, single chain amphiphiles and simple lipids from a mix of CO, CO2, and H2. A key characteristic of these amphiphilic molecules is the ability to self-assemble in aqueous phases into more organized structures called vesicles, which form a selectively permeable boundary and serve the function of containing and concentrating other organic molecules. The ability to form cell like structures also makes these compounds more likely to be mistaken for biogenic. Hydrothermal simulation experiments were conducted from oxalic or formic acid in water at 175 C for 72 hr. The molecular and isotopic composition of the products of these reactions were determined and compared to biogenic fractionations . Preliminary results indicate isotopic fractionation during abiotic hydrocarbon synthesis in hydrothermal environments is on par with biological carbon fixation.

  7. Insights Into Atmospheric Aqueous Organic Chemistry Through Controlled Experiments with Cloud Water Surrogates

    NASA Astrophysics Data System (ADS)

    Turpin, B. J.; Ramos, A.; Kirkland, J. R.; Lim, Y. B.; Seitzinger, S.

    2011-12-01

    There is considerable laboratory and field-based evidence that chemical processing in clouds and wet aerosols alters organic composition and contributes to the formation of secondary organic aerosol (SOA). Single-compound laboratory experiments have played an important role in developing aqueous-phase chemical mechanisms that aid prediction of SOA formation through multiphase chemistry. In this work we conduct similar experiments with cloud/fog water surrogates, to 1) evaluate to what extent the previously studied chemistry is observed in these more realistic atmospheric waters, and 2) to identify additional atmospherically-relevant precursors and products that require further study. We used filtered Camden and Pinelands, NJ rainwater as a surrogate for cloud water. OH radical (~10-12 M) was formed by photolysis of hydrogen peroxide and samples were analyzed in real-time by electrospray ionization mass spectroscopy (ESI-MS). Discrete samples were also analyzed by ion chromatography (IC) and ESI-MS after IC separation. All experiments were performed in duplicate. Standards of glyoxal, methylglyoxal and glycolaldehyde and their major aqueous oxidation products were also analyzed, and control experiments performed. Decreases in the ion abundance of many positive mode compounds and increases in the ion abundance of many negative mode compounds (e.g., organic acids) suggest that precursors are predominantly aldehydes, organic peroxides and/or alcohols. Real-time ESI mass spectra were consistent with the expected loss of methylglyoxal and subsequent formation of pyruvate, glyoxylate, and oxalate. New insights regarding other potential precursors and products will be provided.

  8. The Official Roman Baths Museum Web Site in the City of Bath

    NSDL National Science Digital Library

    There are baths all over the world, and then there are the very unique baths in Bath, England. As the official site for these marvelous edifices proclaims, they are "the best preserved Roman religious spa from the ancient world." For first-time visitors, the best place to start is "The site today", which is a section that will take visitors around the different parts of this World Heritage Site. In the "Curator's Comments" area, visitors can read comments from Stephen Clews about the ongoing work being done at the site. The site also includes helpful sections on planning a visit and the various collections that are available for use by both the general public and scholars.

  9. Interaction of polar and nonpolar organic pollutants with soil organic matter: sorption experiments and molecular dynamics simulation.

    PubMed

    Ahmed, Ashour A; Thiele-Bruhn, Sören; Aziz, Saadullah G; Hilal, Rifaat H; Elroby, Shaaban A; Al-Youbi, Abdulrahman O; Leinweber, Peter; Kühn, Oliver

    2015-03-01

    The fate of organic pollutants in the environment is influenced by several factors including the type and strength of their interactions with soil components especially SOM. However, a molecular level answer to the question "How organic pollutants interact with SOM?" is still lacking. In order to explore mechanisms of this interaction, we have developed a new SOM model and carried out molecular dynamics (MD) simulations in parallel with sorption experiments. The new SOM model comprises free SOM functional groups (carboxylic acid and naphthalene) as well as SOM cavities (with two different sizes), simulating the soil voids, containing the same SOM functional groups. To examine the effect of the hydrophobicity on the interaction, the organic pollutants hexachlorobenzene (HCB, non-polar) and sulfanilamide (SAA, polar) were considered. The experimental and theoretical investigations explored four major points regarding sorption of SAA and HCB on soil, yielding the following results. 1--The interaction depends on the SOM chemical composition more than the SOM content. 2--The interaction causes a site-specific adsorption on the soil surfaces. 3--Sorption hysteresis occurs, which can be explained by inclusion of these pollutants inside soil voids. 4--The hydrophobic HCB is adsorbed on soil stronger than the hydrophilic SAA. Moreover, the theoretical results showed that HCB forms stable complexes with all SOM models in the aqueous solution, while most of SAA-SOM complexes are accompanied by dissociation into SAA and the free SOM models. The SOM-cavity modeling had a significant effect on binding of organic pollutants to SOM. Both HCB and SAA bind to the SOM models in the order of models with a small cavity>a large cavity>no cavity. Although HCB binds to all SOM models stronger than SAA, the latter is more affected by the presence of the cavity. Finally, HCB and SAA bind to the hydrophobic functional group (naphthalene) stronger than to the hydrophilic one (carboxylic acid) for all SOM models containing a cavity. For models without a cavity, SAA binds to carboxylic acid stronger than to naphthalene. PMID:25486638

  10. Beyond heat baths II: Framework for generalized thermodynamic resource theories

    E-print Network

    Nicole Yunger Halpern

    2014-09-27

    Cutting-edge experiments, which involve the nano- and quantum scales, have been united with thermodynamics, which describes macroscopic systems, via resource theories. Resource theories have modeled small-scale exchanges of heat and information. Recently, the models were extended to particle exchanges, and a family of thermodynamic resource theories was proposed to model diverse baths, interactions, and free energies. This paper motivates and details the family's structure and prospective applications. How to model electrochemical, gravitational, magnetic, and other thermodynamic systems is explained. Szilard's engine and Landauer's Principle are generalized, as resourcefulness is shown to be convertible not only between informational and gravitational-energy forms, but also among varied physical degrees of freedom in the thermodynamic limit. Quantum operators associated with extensive variables offer opportunities to explore nonclassical noncommutation. This generalization of thermodynamic resource theories invites the modeling of realistic systems that might be harnessed to test small-scale statistical mechanics experimentally.

  11. The Holburne Museum of Art, Bath

    NSDL National Science Digital Library

    At present, the only way you can visit the Holburne Museum of Art in Bath is online, since they have closed for refurbishing till 2010. You can read about the plans for the improvements and check out floor plans and the development schedule from a link on the homepage. Visitors will be able to check out the history of the museum's beginnings, the highlights of the fine art and decorative art collections, or search through the collection. Users may also view the museum's exhibitions, learn more about workshops, school programs and more.

  12. Bath and Shower Effect in Spinal Cord: The Effect of Time Interval

    SciTech Connect

    Philippens, Marielle E.P. [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegan (Netherlands)], E-mail: m.philippens@umcutrecht.nl; Pop, Lucas A.M.; Visser, Andries G.; Peeters, Wenny J.M.; Kogel, Albert J. van der [Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegan (Netherlands)

    2009-02-01

    Purpose: To evaluate the time dependency of the sensitizing effect of a large low-dose field on a small high-dose field in the rat cervical spinal cord. Methods and materials: Irradiation experiments with a relatively low dose to a large volume (bath, 2 cm, 4 Gy) were combined with high doses to a small volume (shower, 4.7 mm, 26-43 Gy) at intervals of 8 minutes and 3, 12, and 24 hours. Both a functional score defined as motor impairment and a histologic score characterized as white matter necrosis were used as end points. Results: Application of the 4-Gy bath dose resulted in a significant decrease in 50% isoeffective dose (ED{sub 50}) from 48.7 Gy (small field) to 40.8 Gy. If the interval was extended, the ED{sub 50} increased to 44.4 (3 hours) and 44.8 Gy (12 hours), whereas a 24-hour interval resulted in a significant increase to 51.9 Gy. If the histologic end point was considered, the ED{sub 50} for all dose-response curves decreased slightly with 0.2 to 2.6 Gy without significantly changing the kinetics. Conclusions: The bath effect as applied in the bath-and-shower experiment lasted for at least 12 hours and disappeared in the 24-hour interval. This time scale clearly deviates from the repair kinetics in spinal cord derived from low-dose-rate and fractionated irradiations.

  13. Teaching Catalytic Antibodies to Undergraduate Students: An Organic Chemistry Lab Experiment

    NASA Astrophysics Data System (ADS)

    Shulman, Avidor; Keinan, Ehud; Shabat, Doron; Barbas, Carlos F., III

    1999-07-01

    Only 13 years ago, few believed that antibodies could be catalytic or that any protein could be made to order to perform a catalytic task. The field has quickly matured from initial proof of concept and demonstration of fundamental enzyme-like characteristics to one in which antibodies have catalyzed an extremely broad range of organic transformations. Now that the first catalytic antibody is commercially available, it is possible to bring these novel biocatalysts into the classroom so every student can gain hands-on experience and carry out experiments on the cutting edge of scientific discovery. This lab project deals with antibody-catalyzed aldol condensations. It includes the (i) synthesis of substrate and product; (ii) HPLC characterization of the antibody-catalyzed reaction; (iii) titration of the antibody active-site; and (iv) analysis of the kinetics of the antibody-catalyzed reaction. The lab project provides training not only in biocatalysis but in a number of related aspects of chemical and biochemical research, including organic synthesis, mechanistic organic chemistry, and chemical kinetics. Students will learn the use of various experimental techniques, such as UV-vis spectroscopy and HPLC, to monitor chemical reactions and determine kinetic parameters. They will be exposed to concepts and terminology of bioorganic chemistry, such as protein structure and function, inhibition and active-site titration, and basic principles of biocatalysis.

  14. Critical care issues in solid organ injury: Review and experience in a tertiary trauma center

    PubMed Central

    Sawhney, Chhavi; Kaur, Manpreet; Gupta, Babita; Singh, P. M.; Gupta, Amit; Kumar, Subodh; Misra, M. C.

    2014-01-01

    Background and Aim: Solid organ (spleen and liver) injuries are dreaded by both surgeons and anesthesiologists because of associated high morbidity and mortality. The purpose of this review is to describe our experience of critical care concerns in solid organ injury, which otherwise has been poorly addressed in the literature. Materials and Methods: Retrospective cohort of solid organ injury (spleen and liver) patients was done from January 2010 to December 2011 in tertiary level trauma Center. Results: Out of 624 abdominal trauma patients, a total of 212 patients (70%) were admitted in intensive care unit (ICU). Their ages ranged from 6 to 74 years (median 24 years). Nearly 89% patients in liver trauma and 84% patients in splenic trauma were male. Mechanism of injury was blunt abdominal trauma in 96% patients and the most common associated injury was chest trauma. Average injury severity score, sequential organ failure assessment, lactate on admission was 16.84, 4.34 and 3.42 mmol/L and that of dying patient were 29.70, 7.73 and 5.09 mmol/L, respectively. Overall mortality of ICU admitted solid organ injury was 15.55%. Major issues of concern in splenic injury were hemorrhagic shock, overwhelming post-splenectomy infection and post-splenectomy vaccination. Issues raised in liver injury are damage control surgery, deadly triad, thromboelastography guided transfusion protocols and hemostatic agents. Conclusions: A protocol-based and multidisciplinary approach in high dependency unit can significantly reduce morbidity and mortality in patients with solid organ injury. PMID:25538517

  15. Water bath temperature control and temperature measurement devices for calorimetry

    Microsoft Academic Search

    J. D. B. Featherstone; N. A. Dickinson

    1977-01-01

    A low-cost water bath temperature control device, and an apparatus designed to monitor temperature variation from a null point both inside a precision calorimeter and in the surrounding bath, are described. Bath control to better than +or-0.002K in the 280-350K region can be achieved. Temperature variations in ranges between +or-2K and +or-0.02K can be measured to better than 5*10-2K and

  16. Heat bath efficiency with a Metropolis-type updating

    SciTech Connect

    Bazavov, Alexei; Berg, Bernd A. [Department of Physics, Florida State University, Tallahassee, Florida 32306-4350 (United States); School of Computational Science, Florida State University, Tallahassee, Florida 32306-4120 (United States)

    2005-06-01

    We illustrate for 4D SU(2) and U(1) lattice gauge theory that sampling with a biased Metropolis scheme is essentially equivalent to using the heat bath algorithm. Only, the biased Metropolis method can also be applied when an efficient heat bath algorithm does not exist. For the examples discussed the biased Metropolis algorithm is also better suited for parallelization than the heat bath algorithms.

  17. First results of the ORGANIC experiment on EXPOSE-R on the ISS

    NASA Astrophysics Data System (ADS)

    Bryson, K. L.; Salama, F.; Elsaesser, A.; Peeters, Z.; Ricco, A. J.; Foing, B. H.

    2015-01-01

    The ORGANIC experiment on EXPOSE-R spent 682 days outside the International Space Station, providing continuous exposure to the cosmic-, solar- and trapped-particle radiation background for fourteen samples: 11 polycyclic aromatic hydrocarbons (PAHs) and three fullerenes. The thin films of the ORGANIC experiment received, during space exposure, an irradiation dose of the order of 14 000 MJ m-2 over 2900 h of unshadowed solar illumination. Extensive analyses were performed on the returned samples and the results compared to ground control measurements. Analytical studies of the returned samples included spectral measurements from the vacuum ultraviolet to the infrared range and time-of-flight secondary ion mass spectrometry. Limited spectral changes were observed in most cases pointing to the stability of PAHs and fullerenes under space exposure conditions. Furthermore, the results of these experiments confirm the known trend in the stability of PAH species according to molecular structure: compact PAHs are more stable than non-compact PAHs, which are themselves more stable than PAHs containing heteroatoms, the last category being the most prone to degradation in the space environment. We estimate a depletion rate of the order of 85 +/- 5% over the 17 equivalent weeks of continuous unshadowed solar exposure in the most extreme case tetracene (smallest, non-compact PAH sample). The insignificant spectral changes (below 10%) measured for solid films of large or compact PAHs and fullerenes indicate a high stability under the range of space exposure conditions investigated on EXPOSE-R.

  18. Recovery process for electroless plating baths

    DOEpatents

    Anderson, R.W.; Neff, W.A.

    1992-05-12

    A process is described for removing, from spent electroless metal plating bath solutions, accumulated byproducts and counter-ions that have deleterious effects on plating. The solution, or a portion thereof, is passed through a selected cation exchange resin bed in hydrogen form, the resin selected from strong acid cation exchangers and combinations of intermediate acid cation exchangers with strong acid cation exchangers. Sodium and nickel ions are sorbed in the selected cation exchanger, with little removal of other constituents. The remaining solution is subjected to sulfate removal through precipitation of calcium sulfate hemihydrate using, sequentially, CaO and then CaCO[sub 3]. Phosphite removal from the solution is accomplished by the addition of MgO to form magnesium phosphite trihydrate. The washed precipitates of these steps can be safely discarded in nontoxic land fills, or used in various chemical industries. Finally, any remaining solution can be concentrated, adjusted for pH, and be ready for reuse. The plating metal can be removed from the exchanger with sulfuric acid or with the filtrate from the magnesium phosphite precipitation forming a sulfate of the plating metal for reuse. The process is illustrated as applied to processing electroless nickel plating baths. 18 figs.

  19. Recovery process for electroless plating baths

    DOEpatents

    Anderson, Roger W. (Farragut, TN); Neff, Wayne A. (Knoxville, TN)

    1992-01-01

    A process for removing, from spent electroless metal plating bath solutions, accumulated byproducts and counter-ions that have deleterious effects on plating. The solution, or a portion thereof, is passed through a selected cation exchange resin bed in hydrogen form, the resin selected from strong acid cation exchangers and combinations of intermediate acid cation exchangers with strong acid cation exchangers. Sodium and nickel ions are sorbed in the selected cation exchanger, with little removal of other constituents. The remaining solution is subjected to sulfate removal through precipitation of calcium sulfate hemihydrate using, sequentially, CaO and then CaCO.sub.3. Phosphite removal from the solution is accomplished by the addition of MgO to form magnesium phosphite trihydrate. The washed precipitates of these steps can be safely discarded in nontoxic land fills, or used in various chemical industries. Finally, any remaining solution can be concentrated, adjusted for pH, and be ready for reuse. The plating metal can be removed from the exchanger with sulfuric acid or with the filtrate from the magnesium phosphite precipitation forming a sulfate of the plating metal for reuse. The process is illustrated as applied to processing electroless nickel plating baths.

  20. 21 CFR 890.5125 - Nonpowered sitz bath.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5125 Nonpowered sitz bath. (a) Identification. A...

  1. 21 CFR 890.5125 - Nonpowered sitz bath.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5125 Nonpowered sitz bath. (a) Identification. A...

  2. 21 CFR 890.5125 - Nonpowered sitz bath.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5125 Nonpowered sitz bath. (a) Identification. A...

  3. 21 CFR 890.5125 - Nonpowered sitz bath.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5125 Nonpowered sitz bath. (a) Identification. A...

  4. 21 CFR 890.5125 - Nonpowered sitz bath.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices § 890.5125 Nonpowered sitz bath. (a) Identification. A...

  5. Quantum decoherence reduction by increasing the thermal bath temperature.

    PubMed

    Montina, A; Arecchi, F T

    2008-03-28

    The well-known increase of the decoherence rate with the temperature, for a quantum system coupled to a linear thermal bath, no longer holds for a different bath dynamics. This is shown by means of a simple classical nonlinear bath, as well as a quantum spin-boson model. The anomalous effect is due to the temperature dependence of the bath spectral profile. In the case of the second model, a link with the quantum Zeno effect is provided. The decoherence reduction via the temperature increase can be relevant for the design of quantum computers. PMID:18517840

  6. Optimization of chemical bath deposited CdS thin films using nitrilotriacetic acid as a complexing agent

    Microsoft Academic Search

    Hani Khallaf; Isaiah O. Oladeji; Lee Chow

    2008-01-01

    We report a design of experiment approach for the optimization of CdS thin films grown by chemical bath deposition using nitrilotriacetic acid (NTA) as a complexing agent. With the help of this approach, we developed a set of experiments that enabled us to maximize the growth rate. In comparison with works reported earlier, a much faster growth rate is achieved.

  7. Impact of materials used in lab and field experiments on the recovery of organic micropollutants.

    PubMed

    Hebig, Klaus H; Nödler, Karsten; Licha, Tobias; Scheytt, Traugott J

    2014-03-01

    Organic micropollutants are frequently detected in the aquatic environment. Therefore, a large number of field and laboratory studies have been conducted in order to study their fate in the environment. Due to the diversity of chemical properties among these compounds some of them may interact with materials commonly used in field and laboratory studies like tubes, filters, or sample bottles. The aim of our experiment was to study the interaction between those materials and an aqueous solution of 43 widely detected basic, neutral, and acidic organic micropollutants hereby covering a broad range of polarities. Experiments with materials were conducted as a batch study using spiked tap water and for different syringe filters by filtration with subsequent fraction collection. The best recoveries over a wide range of organic compounds were observed for batches in contact with the following materials (in descending order) acryl glass, PTFE, HDPE, and PP. The use of Pharmed©, silicone, NBR70, Tygon©, and LDPE should be avoided. Flexible tubing materials especially influence many of the investigated compounds here. Filtration with most of the tested filter types leads to no significant loss of almost all of the investigated micropollutants. Nonetheless, significant mass losses of some compounds (loratadine, fluoxetine, sertraline, and diuron) were observed during the first mL of the filtration process. No systematic correlation between compound properties, tested materials, and observed mass losses could be identified in this study. The behavior of each compound is specific and thus, not predictable. It is therefore suggested to study the interaction of compounds with filters and material prior to the actual experiment or include blank studies. PMID:24365588

  8. Organic Matter Development and Turnover depending on Mineral Composition in an Artificial Soil Incubation Experiment

    NASA Astrophysics Data System (ADS)

    Pronk, G. J.; Heister, K.; Kogel-Knabner, I.

    2012-12-01

    Recent research indicates that minerals play an important role in the formation and stabilization of soil organic matter (SOM). However, it is difficult to determine the effect of mineral composition on SOM development in natural soils where mineral composition is usually not well defined and initial conditions are generally unknown. Therefore, we performed an incubation experiment with so-called "artificial soils" composed of mixtures of clean and well-defined model materials where the development of organic matter could be followed from known initial conditions. The artificial soils were composed of 8 different mixtures of quartz, illite, montmorillonite, ferrihydrite, boehmite and charcoal, manure as carbon substrate and a microbial inoculum extracted from a natural arable soil. These mixtures were incubated in the dark and sampled 4 times over a total incubation time of 18 months. The organic matter (OM) turnover during incubation was followed by measuring CO2 respiration and C and N contents and distribution over particle size fractions with time. Solid-state 13C nuclear magnetic resonance (NMR) spectroscopy and acid hydrolysis were used to determine the development of OM composition. The artificial soil mixtures developed quickly into complex, aggregated, soil-like materials. CO2 respiration was the same for all artificial soil compositions, indicating that microbial degradation was probably limited by nutrient or substrate availability. With increasing incubation time, nitrogen-rich, proteinaceous material, became enriched in the smallest particle size fraction, indicating the accumulation of microbial debris. There was some difference in the distribution of hydrolysable and non-hydrolysable N and organic carbon after 3 months of incubation depending on the type of clay mineral and charcoal presence. However, the artificial soils developed towards more similar systems with increasing incubation time. The artificial soil incubation experiment provided a useful system where the decay and turnover of the original manure substrate under the influence of microbial degradation could be studied. Because of the well-defined composition of the artificial soils this experiment gives us new insight into the dynamics of interactions between specific minerals, OM and charcoal during the decay and turnover of organic matter in a soil-like system.

  9. A global experiment to improve observations of snow: The World Meteorological Organization Solid Precipitation Intercomparison Experiment (WMO-SPICE)

    NASA Astrophysics Data System (ADS)

    Nitu, R.; Rasmussen, R.; Hendrikx, J.; Baker, B.; Joe, P.; Yang, D.; Smith, C.; Earle, M. E.; Lanzinger, E.; Kochendorfer, J.; Roulet, Y.; Wolff, M.; Goodison, B. E.; Liang, H.; Vuglinsky, V.; Timofeev, A.; Koldaev, A.; Sabarini, F.; Mrozinski, L.; Bilish, S.; MacDonell, S.; Aulamo, O.; Harper, A.

    2012-12-01

    The measurement of solid precipitation has been the subject of extensive investigations, including international collaborative studies. These investigations have focused primarily on manual measurement methods and have revealed significant challenges in the measurement of snowfall and snow on the ground. Since these studies were conducted, an increasing percentage of precipitation and snow depth measurements around the world have been obtained using a broad range of automatic instruments, many operated unattended for extensive periods of time. At the same time, new non-catchment type instruments and systems have been introduced for the measurement of solid precipitation. In the context of the transition from manual methods to automatic instruments and with the introduction of new technologies in measurement networks worldwide, there is an acute need for an internationally-coordinated study to understand and characterize the errors in precipitation measurement of in-situ automatic instruments, and their capabilities for measuring solid precipitation. WMO-SPICE has been initiated to focus on the performance of modern automatic instruments measuring solid precipitation and snow depth. In this regard, the key goals are to investigate and report on the measurement of precipitation amount as a function of precipitation type (liquid, solid, mixed), and of snow on the ground (i.e. snow depth). An important outcome will be to develop correction methods and adjustments for measurements from the various automatic gauge and wind shield combinations used in different countries, to enable the provision of better estimates of regional snowfall. WMO-SPICE will begin in November 2012 and will last for two to three winter seasons The paper will present the organization of the experiment, an overview of the participating sites and the instruments selected for inclusion in the intercomparison. The presentation will also include findings from our Pre-SPICE experiments

  10. Early experience of a safety net provider reorganizing into an accountable care organization.

    PubMed

    Hacker, Karen; Santos, Palmira; Thompson, Douglas; Stout, Somava S; Bearse, Adriana; Mechanic, Robert E

    2014-08-01

    Although safety net providers will benefit from health insurance expansions under the Affordable Care Act, they also face significant challenges in the postreform environment. Some have embraced the concept of the accountable care organization to help improve quality and efficiency while addressing financial shortfalls. The experience of Cambridge Health Alliance (CHA) in Massachusetts, where health care reform began six years ago, provides insight into the opportunities and challenges of this approach in the safety net. CHA's strategies include care redesign, financial realignment, workforce transformation, and development of external partnerships. Early results show some improvement in access, patient experience, quality, and utilization; however, the potential efficiencies will not eliminate CHA's current operating deficit. The patient population, payer mix, service mix, cost structure, and political requirements reduce the likelihood of financial sustainability without significant changes in these factors, increased public funding, or both. Thus the future of safety net institutions, regardless of payment and care redesign success, remains at risk. PMID:24842968

  11. Organic Aerosol Formation in the Humid, Photochemically-Active Southeastern US: SOAS Experiments and Simulations

    NASA Astrophysics Data System (ADS)

    Sareen, N.; Lim, Y. B.; Carlton, A. G.; Turpin, B. J.

    2013-12-01

    Aqueous multiphase chemistry in the atmosphere can lead to rapid transformation of organic compounds, forming highly oxidized low volatility organic aerosol and, in some cases, light absorbing (brown) carbon. Because liquid water is globally abundant, this chemistry could substantially impact climate, air quality, health, and the environment. Gas-phase precursors released from biogenic and anthropogenic sources are oxidized and fragmented forming water-soluble gases that can undergo reactions in the aqueous phase (in clouds, fogs, and wet aerosols) leading to the formation of secondary organic aerosol (SOAAQ). Recent studies have highlighted the role of certain precursors like glyoxal, methylglyoxal, glycolaldehyde, acetic acid, acetone, and epoxides in the formation of SOAAQ. The goal of this work is to identify other precursors that are atmospherically important. In this study, ambient mixtures of water-soluble gases were scrubbed from the atmosphere at Brent, Alabama during the Southern Oxidant and Aerosol Study (SOAS). Four mist chambers in parallel collected ambient gases in a DI water medium at 20-25 LPM with a 4 hr collection time. Total organic carbon (TOC) values in daily composited samples were 64-180 ?M. Aqueous OH radical oxidation experiments were conducted with these mixtures in a newly designed cuvette chamber to understand the formation of SOA through gas followed by aqueous chemistry. OH radicals (3.5E-2 ?M [OH] s-1) were formed in-situ in the chamber, continuously by H2O2 photolysis. Precursors and products of these aqueous OH experiments were characterized using ion chromatography (IC), electrospray ionization mass spectrometry (ESI-MS), and IC-ESI-MS. ESI-MS results from a June 12th, 2013 sample showed precursors to be primarily odd, positive mode ions, indicative of the presence of non-nitrogen containing alcohols, aldehydes, organic peroxides, or epoxides. Products were seen in the negative mode and included organic acid ions like pyruvate and oxalate. The results from this study will be used to better understand aqueous chemistry in clouds/fogs and to identify precursors for laboratory study of wet aerosol, fog, and cloud chemistry.

  12. Method of preparing silicon carbide particles dispersed in an electrolytic bath for composite electroplating of metals

    DOEpatents

    Peng, Yu-Min (Hsinchu, TW); Wang, Jih-Wen (Hsinchu, TW); Liue, Chun-Ying (Tau-Yung, TW); Yeh, Shinn-Horng (Kaohsiung, TW)

    1994-01-01

    A method for preparing silicon carbide particles dispersed in an electrolytic bath for composite electroplating of metals includes the steps of washing the silicon carbide particles with an organic solvent; washing the silicon carbide particles with an inorganic acid; grinding the silicon carbide particles; and heating the silicon carbide particles in a nickel-containing solution at a boiling temperature for a predetermined period of time.

  13. The PROCESS experiment: an astrochemistry laboratory for solid and gaseous organic samples in low-earth orbit.

    PubMed

    Cottin, Hervé; Guan, Yuan Yong; Noblet, Audrey; Poch, Olivier; Saiagh, Kafila; Cloix, Mégane; Macari, Frédérique; Jérome, Murielle; Coll, Patrice; Raulin, François; Stalport, Fabien; Szopa, Cyril; Bertrand, Marylène; Chabin, Annie; Westall, Frances; Chaput, Didier; Demets, René; Brack, André

    2012-05-01

    The PROCESS (PRebiotic Organic ChEmistry on the Space Station) experiment was part of the EXPOSE-E payload outside the European Columbus module of the International Space Station from February 2008 to August 2009. During this interval, organic samples were exposed to space conditions to simulate their evolution in various astrophysical environments. The samples used represent organic species related to the evolution of organic matter on the small bodies of the Solar System (carbonaceous asteroids and comets), the photolysis of methane in the atmosphere of Titan, and the search for organic matter at the surface of Mars. This paper describes the hardware developed for this experiment as well as the results for the glycine solid-phase samples and the gas-phase samples that were used with regard to the atmosphere of Titan. Lessons learned from this experiment are also presented for future low-Earth orbit astrochemistry investigations. PMID:22680688

  14. Spectral features of a many-body-localized system weakly coupled to a bath

    NASA Astrophysics Data System (ADS)

    Nandkishore, Rahul; Gopalakrishnan, Sarang; Huse, David A.

    2014-08-01

    We study many-body-localized (MBL) systems that are weakly coupled to thermalizing environments, focusing on the spectral functions of local operators. These spectral functions carry signatures of localization even away from the limit of perfectly isolated systems. We find that, in the limit of vanishing coupling to a bath, MBL systems come in two varieties, with either discrete or continuous local spectra. Both varieties of MBL systems exhibit a "soft gap" at zero frequency in the spatially averaged spectral functions of local operators, which serves as a diagnostic for localization. We estimate the degree to which coupling to a bath broadens these spectral features, and we find that some characteristics of incipient localization survive as long as the system-bath coupling is much weaker than the characteristic energy scales of the system. We discuss the crossover to localization that occurs as the coupling to the external bath is tuned to zero. Since perfect isolation is impossible, we expect the ideas discussed in this paper to be relevant for experiments on many-body localization.

  15. The Determination of the Stereochemistry of Erythro-1,2-Diphenyl-1,2-Ethanediol: An Undergraduate Organic Experiment.

    ERIC Educational Resources Information Center

    Rowland, Alex T.

    1983-01-01

    Describes an undergraduate organic chemistry experiment designed to illustrate the power of nuclear magnetic reasonance spectroscopy in a determination of the configurations at centers of chirality of various isomers of acyclic systems. Provides a background discussion and experimental procedure. (JM)

  16. ORGANIC CONTAMINANT DISTRIBUTION IN SEDIMENTS, POLYCHAETES (NEREIS VIRENS) AND THE AMERICAN LOBSTER, HOMARUS AMERICANUS IN A LABORATORY FOOD CHAIN EXPERIMENT

    EPA Science Inventory

    A laboratory experiment was conducted to investigate the transfer of organic contaminants from an environmentally contaminated marine sediment through a simple marine food chain. The infaunal polychaete, Nereis virens, was exposed to contaminated sediment collected from the Passa...

  17. Rapid heating experiments demonstrate the usefulness of organic molecules as an earthquake thermometer

    NASA Astrophysics Data System (ADS)

    Sheppard, R. E.; Polissar, P. J.; Savage, H. M.

    2012-12-01

    Measuring temperature rise due to an earthquake would elucidate the frictional characteristics of a fault during rapid slip. We developed a new paleothermometer for fault zones using the thermal maturity of organic compounds as a temperature proxy. The kinetics of these reactions are highly nonlinear, and previous experiments to constrain the kinetic parameters have only been accomplished on long time scales. We ran a series of rapid heating experiments designed to determine these parameters specifically on short time scales. Here, we focus on the kinetics of methylphenanthrenes, aromatic molecules whose pattern of methylation changes with thermal maturity. The MPI-1 thermal maturity index is a ratio of methylphenanthrene's refractory 2- and 3-methylphenanthrene isomers relative to the less stable 9- and 1-methylphenanthrene isomers, and thus increases with increasing temperature. Methylphenanthrenes are relevant to the study of fault heating as they are consistently found in faults exhumed from depths shallower than 4km. To address whether methylphenanthrenes react at earthquake rates, we conducted rapid hydrous pyrolysis experiments in a small stainless steel reactor with a carburized inner surface. For each experiment, the reactor was partially filled with water and Woodford Shale, an organic-rich, thermally immature quartzose claystone sampled in central Oklahoma. The reactor was heated for a range of times and temperatures using resistive heating coils. Temperature was controlled using an external thermocouple and a PID controller, while the temperature of the sample was recorded with an internal thermocouple. Steam pressure was monitored using a pressure transducer throughout the experiment. The expelled oil was extracted from the water contained in the reactor using a separatory funnel, and the shale fragments were crushed and extracted via sonication. Both the oil and the shale extractions were then separated using column chromatography. GCMS analysis shows that the methylphenanthrenes do react on short timescales, even at temperatures below what would be reached during a large earthquake. These results provide a more accurate picture of temperature rise on previously studied faults. The Muddy Mountain thrust in Nevada, the Champlain thrust in Vermont, the Punchbowl fault in Southern California, and the proto-decollement on Sitkinak Island, Alaska, all show no difference in MPI-1 values between on- and off-fault samples, suggesting a lack of differential heating. Our experiments allow us to more accurately estimate the maximum temperature rise that could have occurred during fault slip without significantly altering the methylphenanthrene thermal maturity.

  18. Transformations in organic sulfur speciation during maturation of Monterey shale: Constraints from laboratory experiments

    SciTech Connect

    Nelson, B.C.; Eglinton, T.I.; Seewald, J.S. [Woods Hole Oceanographic Institution, MA (United States). Dept. of Marine Chemistry and Geochemistry; Vairavamurthy, M.A. [Brookhaven National Lab., Upton, NY (United States); Miknis, F.P. [Western Research Inst., Laramie, WY (United States)

    1995-04-01

    A series of hydrous pyrolysis experiments were conducted at temperatures ranging from 125 to 360C at 350 bars pressure to examine variations in sulfur speciation during thermal maturation of Monterey shale. The total sediment, kerogen and bitumen from each experiment in addition to unheated representatives were analyzed via x-ray absorption spectroscopy, pyrolysis-gas chromatography, {sup 30}NMR spectrometry, elemental analysis, thin-layer chromatography and reflected light microscopy. Based on these measurements, it was possible to recognize three distinct temperature regimes, within which the type and amount of sulfur in the analyzed fractions underwent transformations: (1) between 150 and 225C significant proportion of kerogen-bound sulfur is lost probably due to the collapse of polysulfide bridges; (2) between 225 and 275C, cleavage of -S-S- and -S-C- linkages within the kerogen is believed to occur, resulting in substantial production of polar sulfur-rich bitumen; (3) above 275C total bitumen yields as well as the proportion of bitumen sulfur decrease, while C-C bond scission leads to increased yields of saturated and aromatic hydrocarbons. The results from this study clearly and quantitatively establish a link between organically-bound sulfur, and more specifically, organic polysulfides, and the low-temperature evolution of soluble petroleum-like products (bitumen) from sulfur-rich source rocks.

  19. University of Bath Opus End User Licence V1.2

    E-print Network

    McCusker, Guy

    University of Bath Opus End User Licence V1.2 The latest version of this document is available from the University of Bath Opus website at http://opus.bath.ac.uk The Bath Opus Maximising the impact of your held within the University of Bath's Online Publications Store ("Opus") is based on your acceptance

  20. Absence/presence calling in microarray-based CGH experiments with non-model organisms

    PubMed Central

    Jonker, Martijs J.; de Leeuw, Wim C.; Marinkovi?, Marino; Wittink, Floyd R. A.; Rauwerda, Han; Bruning, Oskar; Ensink, Wim A.; Fluit, Ad C.; Boel, C. H.; de Jong, Mark; Breit, Timo M.

    2014-01-01

    Structural variations in genomes are commonly studied by (micro)array-based comparative genomic hybridization. The data analysis methods to infer copy number variation in model organisms (human, mouse) are established. In principle, the procedures are based on signal ratios between test and reference samples and the order of the probe targets in the genome. These procedures are less applicable to experiments with non-model organisms, which frequently comprise non-sequenced genomes with an unknown order of probe targets. We therefore present an additional analysis approach, which does not depend on the structural information of a reference genome, and quantifies the presence or absence of a probe target in an unknown genome. The principle is that intensity values of target probes are compared with the intensities of negative-control probes and positive-control probes from a control hybridization, to determine if a probe target is absent or present. In a test, analyzing the genome content of a known bacterial strain: Staphylococcus aureus MRSA252, this approach proved to be successful, demonstrated by receiver operating characteristic area under the curve values larger than 0.9995. We show its usability in various applications, such as comparing genome content and validating next-generation sequencing reads from eukaryotic non-model organisms. PMID:24771343

  1. Column experiment to study isotope fractionation of volatile organic contaminants in porous media under unsaturated conditions

    NASA Astrophysics Data System (ADS)

    Jeannottat, Simon; Hunkeler, Daniel; Breider, Florian

    2010-05-01

    Pollution by organic contaminants such as petroleum hydrocarbons and chlorinated solvents is common in industrialized countries. The use of stable isotope analysis is increasingly recognized as a powerful technique for investigating the behaviour of organic or inorganic contaminants. Recently, compound-specific isotope analysis (CSIA) has proven to be an effective tool to confirm and quantify in-situ biodegradation by indigenous microbial populations in groundwater.In contrast, only few studies have investigated the use of CSIA in the unsaturated zone. In the unsaturated zone, the main potential applications of CSIA include the assessment of biodegradation and the fingerprinting of different sources of petroleum hydrocarbon or chlorinated solvents vapours. However, it has to be taken into account that isotope ratios in the unsaturated zone can vary due to diffusion and volatilization in addition to biodegradation. For application of isotope methods in the unsaturated zone, it is crucial to quantify isotopic fractionation resulting from physico-chemical and transport processes. The study is focused on laboratory experiments that investigate the effect of vaporization and diffusion on isotope ratios. The effect of diffusion is carried out using a column experiment setup that can be considered to represent VOC transport from a floating NAPL towards the atmosphere. Furthermore, additional column and batch experiments will be conducted to better understand the effect of biodegradation. Volatilization is studied with an other experimental setup. In addition, a mathematical framework was developed to simulate the isotope evolution in the column study. Since the initial experiments aimed at investigating the effect of vaporization and diffusion only, the column is filled with dry quartz sand in order to avoid perturbations of concentration profiles by humidity or adsorption on organic matter. An activated sand will later be used for the biodegradation experiments. A mixture of nine contaminants (pentane, MTBE, hexane, benzene, isooctane, methylcyclohexane, toluene, octane and xylene) that represents a wide range of hydrocarbons is emplaced in the column. Periodical measurements of concentrations and ?13C values were carried out in the source chamber and at different distances along the column. A depletion of 13C with distance is observed, which is due to faster diffusion of substances enriched in 12C. The shift of ?13C values towards more negative values is more significant during the first hours of the experiment. After some hours, the value stabilizes when a steady state is reached. These results fit well the analytical models. These results demonstrate that stable isotope profiles are reached under steady state conditions even though molecules with light isotopes only diffuse faster than molecules with heavy isotopes. This is an important finding for the application of isotope analysis to link VOC vapours to contaminant sources and to demonstrate reactive processes based on shifts in isotope ratios. Further experiments will be conducted to study the isotopic response to diffusion, vaporization and biodegradation of chlorinated solvents (PCE, TCE) using quite a similar column setup. Stable hydrogen and chlorine isotopes will also be measured during the same experiments in order to better constrain the different processes and fingerprinting sources of contaminations.

  2. Measurement of the ambient organic aerosol volatility distribution: application during the Finokalia Aerosol Measurement Experiment (FAME2008)

    Microsoft Academic Search

    B. H. Lee; E. Kostenidou; L. Hildebrandt; I. Riipinen; G. J. Engelhart; C. Mohr; P. F. Decarlo; N. Mihalopoulos; A. S. H. Prevot; U. Baltensperger; S. N. Pandis

    2010-01-01

    A variable residence time thermodenuder (TD) was combined with an Aerodyne Aerosol Mass Spectrometer (AMS) and a Scanning Mobility Particle Sizer (SMPS) to measure the volatility distribution of aged organic aerosol in the Eastern Mediterranean during the Finokalia Aerosol Measurement Experiment in May of 2008 (FAME-2008). A new method for the quantification of the organic aerosol volatility distribution was developed

  3. A comparison of the performance of nine soil organic matter models using datasets from seven long-term experiments

    Microsoft Academic Search

    P. Smith; J. U. Smith; D. S. Powlson; W. B. McGill; J. R. M. Arah; O. G. Chertov; K. Coleman; U. Franko; S. Frolking; D. S. Jenkinson; L. S. Jensen; R. H. Kelly; H. Klein-Gunnewiek; A. S. Komarov; C. Li; J. A. E. Molina; T. Mueller; W. J. Parton; J. H. M. Thornley; A. P. Whitmore

    1997-01-01

    Nine soil organic models were evaluated using twelve datasets from seven long-term experiments. Datasets represented three different land-uses (grassland, arable cropping and woodland) and a range of climatic conditions within the temperate region. Different treatments (inorganic fertilizer, organic manures and different rotations) at the same site allowed the effects of differing land management to be explored. Model simulations were evaluated

  4. VARIABILITY OF AQUIFER SORPTION PROPERTIES IN A FIELD EXPERIMENT ON GROUNDWATER TRANSPORT OF ORGANIC SOLUTES: METHODS AND PRELIMINARY RESULTS

    EPA Science Inventory

    Methods to characterize the organic solute sorption distribution coefficient, organic carbon content, and specific surface area of aquifer solids from the site of a field experiment on solute transport in groundwater were refined for application to small subsamples of 10-cm depth...

  5. Avalanche dynamics, surface roughening, and self-organized criticality: Experiments on a three-dimensional pile of rice

    E-print Network

    Wijngaarden, Rinke J.

    Avalanche dynamics, surface roughening, and self-organized criticality: Experiments on a three-organized criticality. The avalanches that occur on the surface of a pile of rice are found to exhibit finite size scaling in their probability distribution. The critical exponents are 1.21(2) for the avalanche size

  6. Self-organized criticality induced by quenched disorder: Experiments on flux avalanches in NbHx films

    E-print Network

    Wijngaarden, Rinke J.

    Self-organized criticality induced by quenched disorder: Experiments on flux avalanches in Nb, the avalanche sizes are power- law distributed and show finite-size scaling, as expected from self-organized criticality SOC . Furthermore, the shape of the avalanches is observed to be fractal. In the absence

  7. Processing a printed wiring board by single bath electrodeposition

    DOEpatents

    Meltzer, Michael P. (Oakland, CA); Steffani, Christopher P. (Livermore, CA); Gonfiotti, Ray A. (Livermore, CA)

    2010-12-07

    A method of processing a printed wiring board. Initial processing steps are implemented on the printed wiring board. Copper is plated on the printed wiring board from a bath containing nickel and copper. Nickel is plated on the printed wiring board from a bath containing nickel and copper and final processing steps are implemented on the printed wiring board.

  8. 5. UNIT VENTILATOR, MEN'S BATH HALL, SHOWING POSITION AGAINST WALL ...

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

    5. UNIT VENTILATOR, MEN'S BATH HALL, SHOWING POSITION AGAINST WALL ABOVE THE BATHS. - Hot Springs National Park, Bathhouse Row, Ozark Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  9. University of Bath Carbon Management Plan working with

    E-print Network

    Burton, Geoffrey R.

    Change Levy CHP Combined Heat and Power CIF2 Capital Investment Framework 2 CMB Carbon Management BoardUniversity of Bath Carbon Management Plan working with Page 1 University of Bath Carbon Management Programme Carbon Management Plan (CMP) Date: March 2011 Version number: Final, approved by Council, March

  10. Chemical Safety: Molten Salt Baths Cited as Lab Hazards.

    ERIC Educational Resources Information Center

    Baum, Rudy

    1982-01-01

    Discusses danger of explosions with molten salts baths, commonly used as heat-transfer media. One such explosion involved use of a bath containing 3-lb sodium nitrite and 1-lb potassium thiocyanate. Although most commercially available mixtures for heat transfer contain oxidizers, a reducer (thiocyanate) was included which possibly triggered the…

  11. Optimization of Chemical Bath Deposited Cadmium Sulfide Thin Films

    Microsoft Academic Search

    R. C. Weast; Teil B; Verlag Chemie; Lee Chow

    We report the optimization of CdS thin film grown by chemical bath deposition where homogenous reactions are min- imized. The optimum parameters have enabled us to maximize the thickness of the deposited film in a single dip and to grow thicker films by periodically replenishing the concentration of reactants while the substrate remains continuously dipped in the reaction bath. Characterization

  12. Approved by LMT, November 2006 University of Bath Archives

    E-print Network

    Burton, Geoffrey R.

    Approved by LMT, November 2006 University of Bath Archives Special Collections Archives interests and to preserve an historical record of the University'. In addition to the archives of the institution itself, the University of Bath holds a small collection of archival material donated

  13. Uncoupling of Bacterial and Terrigenous Dissolved Organic Matter Dynamics in Decomposition Experiments

    PubMed Central

    Herlemann, Daniel P. R.; Manecki, Marcus; Meeske, Christian; Pollehne, Falk; Labrenz, Matthias; Schulz-Bull, Detlef; Dittmar, Thorsten; Jürgens, Klaus

    2014-01-01

    The biodegradability of terrigenous dissolved organic matter (tDOM) exported to the sea has a major impact on the global carbon cycle, but our understanding of tDOM bioavailability is fragmentary. In this study, the effects of preparative tDOM isolation on microbial decomposition were investigated in incubation experiments consisting of mesocosms containing mesohaline water from the Baltic Sea. Dissolved organic carbon (DOC) consumption, molecular DOM composition, bacterial activities, and shifts in bacterial community structure were compared between mesocosms supplemented with riverine tDOM, either as filtered, particle-free river water or as a concentrate obtained by lyophilization/tangential ultrafiltration, and those containing only Baltic Sea water or river water. As shown using ultra-high-resolution mass spectrometry (15 Tesla Fourier-transform ion cyclotron resonance mass spectrometry, FT-ICR-MS) covering approximately 4600 different DOM compounds, the three DOM preparation protocols resulted in distinct patterns of molecular DOM composition. However, despite DOC losses of 4–16% and considerable bacterial production, there was no significant change in DOM composition during the 28-day experiment. Moreover, tDOM addition affected neither DOC degradation nor bacterial dynamics significantly, regardless of the tDOM preparation. This result suggested that the introduced tDOM was largely not bioavailable, at least on the temporal scale of our experiment, and that the observed bacterial activity and DOC decomposition mainly reflected the degradation of unknown, labile, colloidal and low-molecular weight DOM, both of which escape the analytical window of FT-ICR-MS. In contrast to the different tDOM preparations, the initial bacterial inoculum and batch culture conditions determined bacterial community succession and superseded the effects of tDOM addition. The uncoupling of tDOM and bacterial dynamics suggests that mesohaline bacterial communities cannot efficiently utilize tDOM and that in subarctic estuaries other factors are responsible for the removal of imported tDOM. PMID:24718626

  14. Copper Plating from Non-Cyanide Alkaline Baths

    NASA Astrophysics Data System (ADS)

    Li, Minggang; Wei, Guoying; Wang, Jianfang; Li, Meng; Zhao, Xixi; Bai, Yuze

    2014-12-01

    Non-cyanide alkaline bath was used to prepare copper thin films. Influences of various temperatures on deposition rates, surface morphologies and microstructures of films were investigated. Copper thin films prepared from non-cyanide alkaline bath show typical nodular structures. Copper films fabricated at higher temperature possess rough surface due to hydrolysis of complexing agents. According to the XRD patterns, all deposited films were crystalline and showed Cu (111), Cu (200) and Cu (220) peaks. The intensity of peak (200) increases gradually with the rise on bath temperatures. Films with maximum thickness (7.5 ?m) could be obtained at the temperature of 40°C. From the cyclic voltammetry curve, it was found that the cathodic polarization decreased slightly with increase of bath temperatures. In addition, when the bath temperature was equal to 50°C, current efficiency could reach to 96.95%.

  15. Relationships between organic nitrates and surface ozone destruction during Polar Sunrise Experiment 1992

    NASA Astrophysics Data System (ADS)

    Muthuramu, K.; Shepson, P. B.; Bottenheim, J. W.; Jobson, B. T.; Niki, H.; Anlauf, K. G.

    1994-12-01

    Concurrent measurements of total reactive odd nitrogen species (i.e., NOy) and its major components, including organic nitrates, were carried out during 1992 Polar Sunrise Experiment (PSE92) at Alert, Northwest Territories, Canada, to investigate the episodic depletion of surface level ozone following polar sunrise. A series of C3-C7 alkyl nitrates formed from the atmospheric oxidation of hydrocarbons was measured daily during the 13-week study period (January 22 to April 22). In addition, a large number of gas chromatography/electron capture detector (GC/ECD) peaks with retention times greater than those of the hexyl nitrates were also identified as species containing -ONO2 group(s), using a nitrogen specific detector. The total concentrations of these organic nitrates ranged from 34 to 128 parts per trillion by volume and the distribution in the dark period was found to be similar to that found for rural lower-latitude air masses. In contrast to observations made at lower latitudes where alkyl nitrates make a relatively small contribution to NOy, the organic nitrates at Alert were found to contribute between 7 and 20% of the total odd nitrogen species. After polar sunrise the total concentrations of these organic nitrates decreased steadily, due primarily to the consumption of larger (>C4) alkyl nitrates. The C3 alkyl nitrate concentrations showed little variation during this study. During ozone depletion episodes in April there was a positive correlation between the concentration of the larger organic nitrates and ozone. Most surprisingly, the ratio of concentrations of isomeric alkyl nitrates with carbon numbers ?5, and in particular those involving the C5 isomers, was found to show substantial variations coinciding with the O3 depletion events. This change in the isomeric alkyl nitrate ratios implies a substantial chemical processing of the air masses exhibiting ozone depletion. The possible mechanisms, which must involve consumption of the organic nitrates by either OH radicals or Cl atoms, are discussed in the context of the chemical and meteorological observations conducted at Alert during these ozone depletion events.

  16. Laboratory Experiments on Electrochemical Remediation of the Environment. Part 2: Microscale Indirect Electrolytic Destruction of Organic Wastes

    Microsoft Academic Search

    Jorge G. Ibanez; M. M. Singh; R. M. Pike; Z. Szafran

    1997-01-01

    The objective of this experiment is to destroy, at the microscale level, a sample of surrogate organic waste by generating a powerful oxidizer at the anode of an electrochemical cell. This generated species oxidizes the waste to harmless products. The oxidizer can then be regenerated and recycled. Specifically, this experiment utilizes a redox mediator with a high standard potential (i.e.,

  17. 40 CFR 420.80 - Applicability; description of the salt bath descaling subcategory.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...true Applicability; description of the salt bath descaling subcategory. 420.80...STEEL MANUFACTURING POINT SOURCE CATEGORY Salt Bath Descaling Subcategory § 420.80 Applicability; description of the salt bath descaling subcategory....

  18. 40 CFR 420.80 - Applicability; description of the salt bath descaling subcategory.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...false Applicability; description of the salt bath descaling subcategory. 420.80...STEEL MANUFACTURING POINT SOURCE CATEGORY Salt Bath Descaling Subcategory § 420.80 Applicability; description of the salt bath descaling subcategory....

  19. 40 CFR 420.80 - Applicability; description of the salt bath descaling subcategory.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...true Applicability; description of the salt bath descaling subcategory. 420.80...STEEL MANUFACTURING POINT SOURCE CATEGORY Salt Bath Descaling Subcategory § 420.80 Applicability; description of the salt bath descaling subcategory....

  20. 40 CFR 420.80 - Applicability; description of the salt bath descaling subcategory.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...true Applicability; description of the salt bath descaling subcategory. 420.80...STEEL MANUFACTURING POINT SOURCE CATEGORY Salt Bath Descaling Subcategory § 420.80 Applicability; description of the salt bath descaling subcategory....

  1. 40 CFR 420.80 - Applicability; description of the salt bath descaling subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...true Applicability; description of the salt bath descaling subcategory. 420.80...STEEL MANUFACTURING POINT SOURCE CATEGORY Salt Bath Descaling Subcategory § 420.80 Applicability; description of the salt bath descaling subcategory....

  2. The Influences of Dissolved Organic Matter on Mercury Biogeochemistry in Mesocosm Experiments in the Florida Everglades

    NASA Astrophysics Data System (ADS)

    Aiken, G. R.; Gilmour, C. A.; Krabbenhoft, D. P.; Orem, W.

    2007-12-01

    Interactions of mercury (Hg) with dissolved organic matter (DOM) play important roles in controlling reactivity, bioavailability and transport of Hg in aquatic systems. Laboratory experiments using a variety of organic matter isolates from surface waters in the Florida Everglades indicate that DOM binds Hg very strongly and is the dominant ligand for Hg in the absence of sulfide. These experiments have also shown that the presence of DOM influences the geochemical behavior of cinnabar (HgS) through the stabilization of nanocolloidal HgS resulting in relatively high Hg concentrations under supersaturated conditions with respect to HgS, a common condition in waters containing measurable sulfide concentrations. In this paper, the results of in-situ mesocosm experiments designed to directly measure the effects of DOM -Hg interactions on Hg biogeochemistry will be described. In these experiments, mesocosms (wetland enclosures), located in the central Everglades region of Water Conservation Area 3A (WCA 3A15), were amended with isotopically enriched Hg (200Hg, 202Hg), sulfate (SO4=) and the hydrophobic organic acid (HPOA) fraction of DOM from a site (F1) in the eutrophic northern Everglades. The use of stable isotope spikes in these studies allowed us to examine the delivery of Hg to surface soils (which are the predominant zones of methylation); partitioning of Hg and MeHg among phases (which impacts bioavailability); net MeHg production; loss of Hg and MeHg through photodemethylation, reduction and volatization; and bioaccumulation. The F1 HPOA isolate, obtained using XAD resins, was more aromatic, had a greater specific ultra-violet absorbance and had previously been shown to be more reactive with Hg than the DOM present at the 3A15 site. The F1 HPOA isolate formed strong DOM-Hg complexes (KDOM') = 1023.2 L kg-1 at pH = 7.0 and I = 0.1) and effectively inhibited the precipitation of HgS in laboratory experiments. Select mesocosms were amended with either F1-HPOA or SO4= resulting in a range of concentrations for each constituent. For the DOM amended mesocosms, DOC concentrations increased from 50-100% and the overall SUVA increased from 2.9 to 3.7 L mg C-1 m-1 relative to control mesocosms, indicating that both the concentration and overall reactivity of the DOM in the amended mesocosms had been altered substantially. In these mesocosms, the concentrations of both ambient and isotopically enriched dissolved Hg increased significantly compared to controls. Greater concentrations of both dissolved ambient and labeled methylmercury were also observed in the DOM amended mesocosms indicating that the added DOM increased Hg bioavailabilty of both Hg pools for methylation. In addition, DOM shielded Hg and MeHg from photodemethylation and volatilization, however, it inhibited subsequent MeHg bioaccumulation. Overall, the addition of DOM resulted in increased concentrations of labeled methylmercury comparable to those measured in mesocosms amended with SO4= suggesting that DOM is an important constituent influencing the methylation of Hg. This effect is likely due to increased concentrations of dissolved Hg in the DOM amended mesocosms.

  3. Subsurface Organics in Aseptic Cores From the MARTE Robotic Drilling Experiment: Ground truth and Contamination Issues

    NASA Astrophysics Data System (ADS)

    Bonaccorsi, R.; Stoker, C. R.

    2006-12-01

    The subsurface is the key environment for searching for life on planets lacking surface life. This includes the search for past/present life on Mars where possible subsurface life could exist [1]. The Mars-Analog-Rio-Tinto-Experiment (MARTE) performed a simulation of a Mars robotic drilling at the RT Borehole#7 Site ~6.07m, atop a massive-pyrite deposit from the Iberian Pyritic Belt. The RT site is considered an important analog of Sinus Meridiani on Mars, an ideal model analog for a subsurface Martian setting [2], and a relevant example of deep subsurface microbial community including aerobic and anaerobic chemoautotrophs [4-5]. Searching for microbes or bulk organics of biological origin in a subsurface sample from a planet is a key scientific objective of Robotic drilling missions. During the 2005 Field experiment 28 minicores were robotically handled and subsampled for life detection experiments under anti-contamination protocols. Ground truth included visual observation of cores and lab based Elemental and Isotope Ratios Mass Spectrometry analysis (EA-IRMS) of bulk organics in Hematite and Gohetite-rich gossanized tuffs, gossan and clay layers within 0-6m-depth. C-org and N-tot vary up to four orders of magnitude among the litter (~11Wt%, 0-1cm) and the mineralized (~3Wt%, 1-3cm) layers, and the first 6 m-depth (C-org=0.02-0.38Wt%). Overall, the distribution/ preservation of plant and soil-derived organics (d13C-org = 26 per mil to 24 per mil) is ten times higher (C-org=0.33Wt%) that in hematite-poor clays, or where rootlets are present, than in hematite- rich samples (C-org=<0.01Wt%). This is consistent with ATP assay (Lightning-MVP, Biocontrol) for total biomass in subsurface (Borehole#7 ~6.07m, ~avg. 153RLU) vs. surface soil samples (~1,500-81,449RLU) [5]. However, the in-situ ATP assay failed in detecting presence of roots during the in-situ life detection experiment. Furthermore, cm-sized roots were overlooked during remote observations. Finally, ATP Luminometry provided insights for potential contamination from core-handling and environmental dust loadings on cleaned/sterilized control surfaces (e.g., 6,782-36,243RLU/cm2). Cleanliness/sterility can be maintained by applying a simple sterile protocol under field conditions. Science results from this research will support future Astrobiology driven drilling mission planned on Mars. Specifically, ground truth offers relevant insights to assess strengths and limits of in-situ/remote observations vs. laboratory measurements. Results from this experiment will also aid the debate on advantages/ disadvantages of manned vs. robotic drilling missions on Mars or other planets. [1] Boston et al., 1997; [2] http://marte.arc.nasa.gov; [3] Stoker, C., et al., 2006 AbSciCon, [4] Stoker et al., submitted; [5] Bonaccorsi., et al., 2006 AbSciCon.

  4. A fermionic bath induced antibunching and coherence in Mollow spectra

    NASA Astrophysics Data System (ADS)

    Karmakar, Anirban; Gangopadhyay, Gautam

    2014-04-01

    In this work, we have derived the modified Bloch equation from the generalized master equation due to the fermionic bath where one needs to consider Grassmann algebra to obtain the similar mathematical structure of the reduced system dynamics, as in the case of a bosonic bath. There is an enhancement of antibunching in the photon emission with an increase in effective temperature. This is in principle a manifestation of the antisymmetric two-particle dynamic anticorrelation in the fermionic bath with a defined chemical potential characterized by the forbidden overlapping. This is evident from the modified fluctuation-dissipation relation. We have compared it thoroughly with an experimental result in the temperature dependent emission characteristics within an environment of quantum dots in a Hanburry-Brown-Twiss set-up. For the fermionic bath, an effective temperature assisted coherence phenomenon is induced in the system dynamics, which is reflected in the resonance fluorescence spectrum with the variation of chemical potential. In the Mollow's absorption spectra, when the Rabi frequency is sufficiently low, the side peaks appear as chemical potential induced coherence phenomenon rather than the traditional field induced one. The subsequent gain in the probe wave is evidently of thermal origin, where the energy is fully supplied by the fermionic bath at non-zero temperatures. This is not possible for a bosonic bath—an example of the extraction of coherence from the fermionic bath.

  5. Bath for electrolytic reduction of alumina and method therefor

    DOEpatents

    Brown, Craig W. (Seattle, WA); Brooks, Richard J. (Seattle, WA); Frizzle, Patrick B. (Lynnwood, WA); Juric, Drago D. (Bulleen, AU)

    2002-11-26

    An electrolytic bath for use during the electrolytic reduction of alumina to aluminum. The bath comprises a molten electrolyte having the following ingredients: (a) AlF.sub.3 and at least one salt selected from the group consisting of NaF, KF, and LiF; and (b) about 0.004 wt. % to about 0.2 wt. %, based on total weight of the molten electrolyte, of at least one transition metal or at least one compound of the metal or both. The compound may be, for example, a fluoride, oxide, or carbonate. The metal can be nickel, iron, copper, cobalt, or molybdenum. The bath can be employed in a combination that includes a vessel for containing the bath and at least one non-consumable anode and at least one dimensionally stable cathode in the bath. Employing the bath of the present invention during electrolytic reduction of alumina to aluminum can improve the wetting of aluminum on a cathode by reducing or eliminating the formation of non-metallic deposits on the cathode. Removing sulfur from the bath can also minimize cathode deposits. Aluminum formed on the cathode can be removed directly from the cathode.

  6. Crystallographic Structure Determination: An Experiment for Organic Analysis and Other Nontraditional Venues

    NASA Astrophysics Data System (ADS)

    Hunter, Allen D.

    1998-10-01

    Single crystal diffraction analysis is a technique being increasingly utilized by non-specialists. To give students an introductory experience in this method, a one to two hour lecture and a three hour lab are described for use in courses such as organic analysis, biophysical chemistry, and instrumental methods. This class emphasizes the practical aspects of diffraction analysis, especially how routine structures are solved, how the results are prepared for publication as graphics and tables, and how reliable these results are. The student employ x-ray diffraction analysis software (i.e. SHELXTL) to solve the structures of compounds from supplied crystallographic data sets. Three data sets appropriate for this experiment are provided (i.e. for PhCH2-NH-CHPh-P(O)(OH)(OEt), (h6-1,4-C6H4(NH2)(NMe2))Cr(CO)3, and Pd(Ph2PCH2CH2PPh2)(S2C2(CN)2)) as is a link to a Youngstown State University Structure Center WEB page (i.e. http://www.as.ysu.edu/~adhunter/YSUSC/XRAYDPST/index.html) where additional properly formatted crystallographic data files may be downloaded.

  7. Mineralization of Soil Organic Matter in Two Elevated CO2 by Warming Experiments in Grassland

    NASA Astrophysics Data System (ADS)

    Pendall, E.; Hovenden, M.; Williams, A.; Dijkstra, F. A.; Morgan, J. A.

    2007-12-01

    Experimentally elevated atmospheric CO2 has enhanced carbon (C) allocation belowground, while ecosystem warming has led to losses of soil C due to enhanced mineralization of soil organic matter (SOM). Few investigations of possible interactions between elevated CO2 and temperature have been reported, but the potential for C cycling effects not to be simply additive is high. We have taken advantage of two multi-factor global change experiments being conducted in mixed C3/C4 grasslands to evaluate similarities and differences in responses of SOM mineralization rates. The TasFACE experiment in Tasmania, Australia, has been running for over 5 years, while the Prairie Heating and CO2 Enrichment (PHACE) experiment in Wyoming, USA, has been running for less than 2 years. Both experiments employ mini-FACE systems (enriched plots targeted at 550 at TasFACE and 600 ppm at PHACE) and overhead ceramic infrared emitters (heated plots targeted at +2 degrees C at TasFACE and +1.5/+3 degrees day/night at PHACE). Soil samples collected after 5 years at TasFACE and at the beginning of the second year at PHACE were incubated for three weeks to evaluate changes in labile SOM pool sizes and turnover rates. We hypothesized that elevated CO2 would enhance labile SOM pool size and that warming would reduce it, and that warming would stimulate decomposition rate. Preliminary results suggested that five years of warming enhanced decomposition rate in the TasFACE soils, but only under the C4 grass species, whereas the first two months of warming had no effects on decomposition rate at PHACE. Elevated CO2 increased mineralizable C pool sizes by 10 to 30 percent, depending on depth, in the TasFACE soils, but did not significantly alter C cycling in the PHACE soils. Short experimental duration likely explained the lack of treatment effects seen at PHACE. We plan to continue conducting parallel experiments to track temporal changes in C cycling with the expectation that interactive effects of elevated CO2 and warming may appear over the long term.

  8. Efficacy of Organic Soil Amendments for Management of Heterodera glycines in Greenhouse Experiments

    PubMed Central

    Grabau, Zane J.; Chen, Senyu

    2014-01-01

    In a repeated greenhouse experiment, organic soil amendments were screened for effects on population density of soybean cyst nematode (SCN), Heterodera glycines, and soybean growth. Ten amendments at various rates were tested: fresh plant material of field pennycress, marigold, spring camelina, and Cuphea; condensed distiller’s solubles (CDS), ash of combusted CDS, ash of combusted turkey manure (TMA), marigold powder, canola meal, and pennycress seed powder. Soybeans were grown for 70 d in field soil with amendments and SCN eggs incorporated at planting. At 40 d after planting (DAP), many amendments reduced SCN egg population density, but some also reduced plant height. Cuphea plant at application rate of 2.9% (amendment:soil, w:w, same below), marigold plant at 2.9%, pennycress seed powder at 0.5%, canola meal at 1%, and CDS at 4.3% were effective against SCN with population reductions of 35.2%, 46.6%, 46.7%, 73.2%, and 73.3% compared with control, respectively. For Experiment 1 at 70 DAP, canola meal at 1% and pennycress seed powder at 0.5% reduced SCN population density 70% and 54%, respectively. CDS at 4.3%, ash of CDS at 0.2%, and TMA at 1% increased dry plant mass whereas CDS at 4.3% and pennycress seed powder at 0.1% reduced plant height. For Experiment 2 at 70 DAP, amendments did not affect SCN population nor plant growth. In summary, some amendments were effective for SCN management, but phytoxicity was a concern. PMID:25276000

  9. Efficacy of Organic Soil Amendments for Management of Heterodera glycines in Greenhouse Experiments.

    PubMed

    Grabau, Zane J; Chen, Senyu

    2014-09-01

    In a repeated greenhouse experiment, organic soil amendments were screened for effects on population density of soybean cyst nematode (SCN), Heterodera glycines, and soybean growth. Ten amendments at various rates were tested: fresh plant material of field pennycress, marigold, spring camelina, and Cuphea; condensed distiller's solubles (CDS), ash of combusted CDS, ash of combusted turkey manure (TMA), marigold powder, canola meal, and pennycress seed powder. Soybeans were grown for 70 d in field soil with amendments and SCN eggs incorporated at planting. At 40 d after planting (DAP), many amendments reduced SCN egg population density, but some also reduced plant height. Cuphea plant at application rate of 2.9% (amendment:soil, w:w, same below), marigold plant at 2.9%, pennycress seed powder at 0.5%, canola meal at 1%, and CDS at 4.3% were effective against SCN with population reductions of 35.2%, 46.6%, 46.7%, 73.2%, and 73.3% compared with control, respectively. For Experiment 1 at 70 DAP, canola meal at 1% and pennycress seed powder at 0.5% reduced SCN population density 70% and 54%, respectively. CDS at 4.3%, ash of CDS at 0.2%, and TMA at 1% increased dry plant mass whereas CDS at 4.3% and pennycress seed powder at 0.1% reduced plant height. For Experiment 2 at 70 DAP, amendments did not affect SCN population nor plant growth. In summary, some amendments were effective for SCN management, but phytoxicity was a concern. PMID:25276000

  10. Distance dependence of entanglement generation via a bosonic heat bath

    E-print Network

    Thomas Zell; Friedemann Queisser; Rochus Klesse

    2009-04-16

    Within a generalized Caldeira-Leggett model we analyze the conditions under which a bosonic heat bath can entangle two microscopic quantum systems at a distance $r$. We find that the attainable entanglement is extremely distance-sensitive. Significant entanglement can only be achieved if the systems are within a {\\em microscopic} distance that is of order of the cut-off wavelength $\\lambda$ of the system-bath interaction. At larger distances the maximal entanglement is exponentially suppressed with a decay length of order $\\lambda$. We conclude that entanglement generation via a heat bath is not suitable for entangling remote objects.

  11. Modes of Organic Matter Burial in Mudstones - Observations from Flume Experiments

    NASA Astrophysics Data System (ADS)

    Schieber, J.; Schimmelmann, A.; Bennett, R.; Curry, K.; Douglas, J.

    2012-12-01

    The burial of organic matter (OM) in marine sediments is one of the key geological pathways for global carbon sequestration and intimately linked to levels of atmospheric oxygen and global climate. Carbonaceous mudstones are the sedimentary rock type that records this process in the rock record, and it was long thought that these rocks bear witness to situations where marine snow (OM from surface waters) and mineral matter (mostly clays) settled through oxygen deficient stagnant bottom waters to the seafloor. An increasing number of black shale successions, however, shows evidence of deposition from bottom currents that transported flocculated muds in bedload. Such a mode of deposition seems initially incompatible with enhanced organic matter preservation, particularly in the case of many ancient black shales that accumulated in shallow shelf seas. Upon further consideration, however, accumulation of bedload transported flocculated clay-organic aggregates (dynamic mode) may actually enhance organic matter preservation when compared to gravity settled (passive mode) accumulations of marine snow and mineral grains. Based on the TEM study of experimental sediments where simulated marine-snow and clays were deposited from moving suspensions as well as via gravity settling, we find that flow-deposited OM-clay mixtures show indications of roll-aggregation by floccules and a less porous fabric, whereas still-water settled muds show a more "open" pore structure. In the latter case the microfabric is characterized by dispersed clumps of OM and clays, whereas the microfabrics of flow deposited OM-clay mixtures show small scale OM-bridges between clay particles and OM "coatings" on clays. We propose that the differences in OM-clay association and pore structure exert a significant difference on the way in which the OM in these sediments will be bacterially processed in surface sediments and on how much of the initial OM is likely to enter the rock record. The temperature of depositing flows may also affect how sediment is deposited and what microfabrics we might expect to see in the rock record. Experiments conducted with water cooled to deep ocean temperatures showed a significant change in depositional behavior due to the approximately 50% higher viscosity of cold (5 degrees Celsius) vs warm (23 degrees Celsius) water. The parallel increase in shear stress lowers the critical velocity of sedimentation for the sediments (from 20 cm/sec to 13.5 cm/sec). Further study may reveal significant differences in depositional fabrics between mudstones that were deposited in a warm water environment (tropical shelf) vs. a cold water environment (arctic shelf, deep sea).

  12. Emergence and properties of spice and bath salts: a medicinal chemistry perspective.

    PubMed

    Lewin, Anita H; Seltzman, Herbert H; Carroll, F Ivy; Mascarella, S Wayne; Reddy, P Anantha

    2014-02-27

    Over the past five years the number of internet sites advertising "legal highs" has literally exploded, as have user reports of experiences (both pleasurable and frightening) with these substances and the number of emergency room visits by users. Although the majority of these "legal highs" have been described as bath salts and herbal extracts, most contain neither plant derived compounds nor components of personal hygiene products. So-called "bath salts" largely contain synthetic analogs of the natural compound Khat; spice-related materials, claimed to be "legal marijuana," are mostly synthetic analogs of cannabinoid receptor ligands that were developed as research tools. This review describes the emergence and properties of these two groups of "legal highs" from a medicinal chemist's perspective. PMID:24113072

  13. Quasidark state and quantum interference in the Jaynes-Cummings model with a common bath

    NASA Astrophysics Data System (ADS)

    Wang, Zhihai; Zhou, D. L.

    2014-01-01

    Within the capacity of current experiments, we design a composite atom-cavity system with a common bath, in which the decay channels of the atom and the cavity mode interfere with each other. When the direct atom-cavity coupling is absent, the system can be trapped in a quasidark state (the coherent superposition of excited states for the atom and the cavity mode) without decay even in the presence of the bath. When the atom directly couples with the cavity, the largest decay rate of the composite system will surpass the sum of the two subsystems while the smallest decay rate may achieve 0. This is manifested in the transmission spectrum, where the vacuum Rabi splitting shows an obvious asymmetric character.

  14. Experiences of Organic Dairy Farmers with Ailing Milk Markets - A Sociological Study in Northern Germany

    Microsoft Academic Search

    R. OPPERMANN; G. RAHMANN

    The case refers to organic milk produc- tion and the marketing of organic milk pro- duce. We describe the situation of two groups of organic dairy farmers working in northern Germany. The two groups are confronted with an extremely difficult choice. They have to choose whether they will continue to follow a quality oriented strategy of organic farm- ing or

  15. 21 CFR 740.17 - Foaming detergent bath products.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...17 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS Warning Statements § 740.17 Foaming detergent bath products....

  16. 21 CFR 740.17 - Foaming detergent bath products.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...17 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS Warning Statements § 740.17 Foaming detergent bath products....

  17. 21 CFR 740.17 - Foaming detergent bath products.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...17 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS Warning Statements § 740.17 Foaming detergent bath products....

  18. 21 CFR 740.17 - Foaming detergent bath products.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...17 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS COSMETIC PRODUCT WARNING STATEMENTS Warning Statements § 740.17 Foaming detergent bath products....

  19. 11. GENERAL VIEW OF MEN'S BATH HALL. Hot Springs ...

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

    11. GENERAL VIEW OF MEN'S BATH HALL. - Hot Springs National Park, Bathhouse Row, Fordyce Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  20. 9. VAPOR STALL IN MEN'S BATH HALL. Hot Springs ...

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

    9. VAPOR STALL IN MEN'S BATH HALL. - Hot Springs National Park, Bathhouse Row, Buckstaff Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 Mile North of U.S. Highway 70, Hot Springs, Garland County, AR

  1. 14. STEAM CABINETS & SITZ BATH IN STEAM ROOM. ...

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

    14. STEAM CABINETS & SITZ BATH IN STEAM ROOM. - Hot Springs National Park, Bathhouse Row, Fordyce Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  2. 8. HUBBARD TUB IN MEN'S BATH HALL. Hot Springs ...

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

    8. HUBBARD TUB IN MEN'S BATH HALL. - Hot Springs National Park, Bathhouse Row, Buckstaff Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 Mile North of U.S. Highway 70, Hot Springs, Garland County, AR

  3. 6. HUBBARD TUB, SHOWING WHIRLPOOL MOTOR OUTSIDE BATH STALL. ...

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

    6. HUBBARD TUB, SHOWING WHIRLPOOL MOTOR OUTSIDE BATH STALL. - Hot Springs National Park, Bathhouse Row, Quapaw Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  4. 85. INTERIOR, SECOND FLOOR, SOUTHEAST CORNER BATH, VIEW FROM THE ...

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

    85. INTERIOR, SECOND FLOOR, SOUTHEAST CORNER BATH, VIEW FROM THE WEST - Mark Twain House, 351 Farmington Avenue (corrected from original address of 531 Farmington Avenue), Hartford, Hartford County, CT

  5. 82. INTERIOR, SECOND FLOOR, WEST SIDE BATH, VIEW OF THE ...

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

    82. INTERIOR, SECOND FLOOR, WEST SIDE BATH, VIEW OF THE TUB, WITH SCALE - Mark Twain House, 351 Farmington Avenue (corrected from original address of 531 Farmington Avenue), Hartford, Hartford County, CT

  6. 83. INTERIOR, SECOND FLOOR, WEST SIDE BATH, VIEW OF THE ...

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

    83. INTERIOR, SECOND FLOOR, WEST SIDE BATH, VIEW OF THE TUB, WITHOUT SCALE - Mark Twain House, 351 Farmington Avenue (corrected from original address of 531 Farmington Avenue), Hartford, Hartford County, CT

  7. The University of Bath in a National Context.

    ERIC Educational Resources Information Center

    Taylor, Bryan J. R.

    1982-01-01

    The chief planing officer of the University of Bath outlines the demographic and academic reasons for the institution's recent, unpopular planning and policy decisions. This information is presented in the context of current British national higher education policy. (MSE)

  8. Making Bath Salts for Mother's Day, a Primary Chemistry Lesson

    NSDL National Science Digital Library

    This activity is a guided discovery where students make chemical mixtures using sodium, learn about the Periodic Table, view salt under a microscope, and have a final result of bath salts for the bathtub

  9. Interior view of bath room 05 with original toilet stall, ...

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

    Interior view of bath room 0-5 with original toilet stall, marble surround, and urinal, facing west. - Marine Barracks, Panama Canal, Barracks Building, 100' North of Thatcher Highway, Balboa, Former Panama Canal Zone, CZ

  10. Persistence of soil organic matter as an ecosystem property: implications for experiments, feedbacks, and modeling

    NASA Astrophysics Data System (ADS)

    Schmidt, M. W.; Torn, M. S.

    2012-12-01

    Globally, soil organic matter (SOM) contains more than three times as much carbon as either the atmosphere or terrestrial vegetation. Yet it remains largely unknown why some SOM persists for millennia whereas other SOM decomposes readily—and this limits our ability to predict how soils will respond to land use or climate change. Recent analytical and experimental advances have demonstrated that molecular structure alone does not control SOM stability: in fact, environmental and biological controls predominate. Here we summarize recent understanding and propose ways to include this understanding in a new generation of experiments and soil carbon models, thereby improving predictions of the SOM response to global warming. Numerical models of soil carbon cycling are used to attribute carbon sources and sinks, predict climate-ecosystem feedbacks, and evaluate biofuel and sequestration strategies. Current ecosystem models rest heavily on the concept of recalcitrance and most models partition plant input into pools of different turnover time solely on the basis of plant tissue chemistry. However, recent research enabled by isotopic, spectroscopic, and molecular marker tools finds little evidence that recalcitrance or selective preservation determine the long residence time of SOM. Without the assumption that recalcitrance or molecular structure control decomposition rates, the framework of these models is no longer justified. Some improvements can be made easily; in other areas, research is needed to translate recent findings into new parameters, for example, to predict the effect of organo-mineral interactions and soil depth on decomposition rates. In this presentation, we will describe a new view of soil carbon cycling that is consistent with the new generation of observations, discuss suggested improvements to soil carbon models, and explore the implications for the vulnerability of soil organic carbon.

  11. Chromophoric dissolved organic matter during the Mackenzie River spring freshet: Observations and freeze-thaw experiments

    NASA Astrophysics Data System (ADS)

    Griffin, C. G.; McClelland, J. W.; Vonk, J. E.; Holmes, R. M.; Frey, K. E.

    2012-04-01

    Dissolved organic matter (DOM) in Arctic rivers is characterized by highly seasonal changes in concentrations, fluxes and composition. However, there is still relatively little knowledge of variations in riverine DOM during the spring freshet, when export of DOM is generally highest. Chromophoric dissolved organic matter (CDOM) absorption spectra have been shown to be useful indicators of concentrations and quality of DOM in high-latitude rivers. Here, we present ultraviolet-visible absorption spectra of CDOM, collected during the 2011 spring freshet on the Mackenzie River. The Mackenzie River is a major source of DOM to the coastal Beaufort Sea, delivering nearly 500 kilotons of carbon within the two month spring freshet. A high-resolution time series was collected from the East Channel in the Mackenzie River delta, along with lower-resolution time series of small upland rivers, large tributaries, and the Mackenzie main stem upriver of the delta region. CDOM concentrations, reported as a400, ranged from 1.6 to 26.9 m-1 (average 10.06 ± 4.9 m-1). Spectral slopes (S), which can be used to assess sources and molecular weight of CDOM, correlated well with concentrations. S was generally lower and less variable in small upland rivers than in the Mackenzie or its larger tributaries. These results suggest that the quality and composition of DOM vary substantially during the spring freshet period in the Mackenzie River. In addition, freeze-thaw experiments were conducted to determine whether frozen, archived water can provide reliable measurements of CDOM, regardless of initial DOM quantity or quality. Samples from the six largest Arctic rivers have been collected and archived since 2003, yet it is still unknown whether CDOM measurements from thawed samples are comparable to absorbance immediately after sample collection. Initial results from the Mackenzie river indicate that absorbance in the ultra-violet spectrum is not greatly impacted by freezing. In addition, experiments show that sonication of thawed samples can remedy flocculation and improve the reliability of visible spectrum absorbance. After corrections for freeze-thaw cycles, archived samples will be used to develop algorithms estimating DOM concentrations from satellite remote sensing, and produce spatially explicit time series of DOM variations in large arctic rivers.

  12. Bath for electrolytic reduction of alumina and method therefor

    DOEpatents

    Brown, Craig W. (Seattle, WA); Brooks, Richard J. (Seattle, WA); Frizzle, Patrick B. (Lynnwood, WA); Juric, Drago D. (Bulleen, AU)

    2001-07-10

    An electrolytic bath for use during the electrolytic reduction of alumina to aluminum. The bath comprises a molten electrolyte having the following ingredients: (a) AlF.sub.3 and at least one salt selected from the group consisting of NaF, KF, and LiF; and (b) about 0.004 wt. % to about 0.2 wt. %, based on total weight of the molten electrolyte, of at least one transition metal or at least one compound of the metal or both. The compound may be, for example, a fluoride, oxide, or carbonate. The metal can be nickel, iron, copper, cobalt, or molybdenum. The bath can be employed in a combination that includes a vessel for containing the bath and at least one non-consumable anode and at least one dimensionally stable cathode in the bath. Employing the bath of the present invention during electrolytic reduction of alumina to aluminum can improve the wetting of aluminum on a cathode by reducing or eliminating the formation of non-metallic deposits on the cathode.

  13. The FLAME Deluge: organic aerosol emission ratios from combustion chamber experiments

    NASA Astrophysics Data System (ADS)

    Jolleys, Matthew; Coe, Hugh; McFiggans, Gordon; McMeeking, Gavin; Lee, Taehyoung; Sullivan, Amy; Kreidenweis, Sonia; Collett, Jeff

    2014-05-01

    A high level of variability has been identified amongst organic aerosol (OA) emission ratios (ER) from biomass burning (BB) under ambient conditions. However, it is difficult to assess the influences of potential drivers for this variability, given the wide range of conditions associated with wildfire measurements. Chamber experiments performed under controlled conditions provide a means of examining the effects of different fuel types and combustion conditions on OA emissions from biomass fuels. ERs have been characterised for 67 burns during the second Fire Laboratory at Missoula Experiment (FLAME II), involving 19 different species from 6 fuel types widely consumed in BB events in the US each year. Average normalised dOA/dCO ratios show a high degree of variability, both between and within different fuel types and species, typically exceeding variability between separate plumes in ambient measurements. Relationships with source conditions were found to be complex, with little consistent influence from fuel properties and combustion conditions for the entire range of experiments. No strong correlation across all fires was observed between dOA/dCO and modified combustion efficiency (MCE), which is used as an indicator of the proportional contributions of flaming and smouldering combustion phases throughout each burn. However, a negative correlation exists between dOA/dCO and MCE for some coniferous species, most notably Douglas fir, for which there is also an apparent influence from fuel moisture content. Significant contrasts were also identified between combustion emissions from different fuel components of additional coniferous species. Changes in fire efficiency were also shown to dramatically alter emissions for fires with very similar initial conditions. Although the relationship with MCE is variable between species, there is greater consistency with the level of oxygenation in OA. The ratio of the m/z 44 fragment to total OA mass concentration (f44) as measured by aerosol mass spectrometer (AMS) provides an indication of oxygenation as influenced by combustion processes at source, with dOA/dCO decreasing with increasing f44 for all fuel types. Inconsistencies in the magnitude of the effects associated with each potential influence on dOA/dCO emphasise the lack of a single dominant control on fire emissions, and a dependency on both fuel properties and combustion conditions.

  14. Geochemistry of volatile organic compounds in seawater: Mesocosm experiments with 14C-model compounds

    NASA Astrophysics Data System (ADS)

    Wakeham, Stuart G.; Canuel, Elizabeth A.; Doering, Peter H.

    1986-06-01

    A series of ten radiotracer experiments were conducted in controlled experimental ecosystems (mesocosms) to investigate the behavior of volatile organic compounds (VOC) in seawater. Time-series measurements of the redistribution of 14C-activity within several major pools - dissolved, particulate, intermediate metabolite, and CO 2 - in the ecosystem made possible an evaluation of the rates of processes - volatilization, biodegradation, Sorption and sedimentation - acting to remove VOC from seawater in summer. The behavior of the model 14C-VOC fell into three categories. Aromatic hydrocarbons (benzene, toluene, naphthalene) were subject to both volatilization and biodegradation, with mineralization dominating in summer. Chlorinated C 2-hydrocarbons (tetrachloroethylene) and chlorinated benzenes (chlorobenzene, 1,4-dichlorobenzene, and 1,2,4-trichlorobenzene) were affected only by volatilization and were relatively resistant to biodegradation. Of all the model VOC studied, only aliphatic hydrocarbons (decane and octadecane) were sorbed onto suspended paniculate matter; however, the primary route of loss from the water column appeared to be biodegradation rather than sedimentation. The mesocosm-derived removal rate constants were then applied to estimate summer VOC residence times in Narragansett Bay, Rhode Island of about 1 day for aromatic hydrocarbons, 1 week for the chlorinated VOC and about 1 day for aliphatic hydrocarbons. Residence times in winter might be on the order of 1 week for all VOC.

  15. Interactions between above- and belowground organisms modified in climate change experiments

    NASA Astrophysics Data System (ADS)

    Stevnbak, Karen; Scherber, Christoph; Gladbach, David J.; Beier, Claus; Mikkelsen, Teis N.; Christensen, Søren

    2012-11-01

    Climate change has been shown to affect ecosystem process rates and community composition, with direct and indirect effects on belowground food webs. In particular, altered rates of herbivory under future climate can be expected to influence above-belowground interactions. Here, we use a multifactor, field-scale climate change experiment and independently manipulate atmospheric CO2 concentration, air and soil temperature and drought in all combinations since 2005. We show that changes in these factors modify the interaction between above- and belowground organisms. We use an insect herbivore to experimentally increase aboveground herbivory in grass phytometers exposed to all eight combinations of climate change factors for three years. Aboveground herbivory increased the abundance of belowground protozoans, microbial growth and microbial nitrogen availability. Increased CO2 modified these links through a reduction in herbivory and cascading effects through the soil food web. Interactions between CO2, drought and warming can affect belowground protozoan abundance. Our findings imply that climate change affects aboveground-belowground interactions through changes in nutrient availability.

  16. Fast neutron spectrometry with organic scintillators applied to magnetic fusion experiments

    NASA Astrophysics Data System (ADS)

    Kaschuck, Yu. A.; Esposito, B.; Trykov, L. A.; Semenov, V. P.

    2002-01-01

    Neutron spectrometry with NE213 liquid scintillators is commonly used in thermonuclear fusion experiments to measure the 2.45 and 14.1 MeV neutron flux. We present the unfolded neutron spectrum, which was accumulated during several ohmic deuterium plasma discharges in the Frascati Tokamak Upgrade using a 2?×2? NE213 scintillator. In this paper, we review the application of organic scintillator neutron spectrometers to tokamaks, focusing in particular on the comparison between NE213 and stilbene scintillators. Various aspects of the calibration technique and neutron spectra unfolding procedure are considered in the context of their application for fusion neutron spectrometry. Testing and calibration measurements have been carried out using D-D and D-T neutron generator facilities with both NE213 and stilbene scintillators. The main result from these measurements is that stilbene scintillator has better neutron energy resolution than NE213. Our stilbene detector could be used for the determination of the ion temperature ( Ti) from neutron spectrum broadening in tokamak thermonuclear plasmas with Ti=4 keV and higher.

  17. Determination of tobacco smoking influence on volatile organic compounds constituent by indoor tobacco smoking simulation experiment

    NASA Astrophysics Data System (ADS)

    Xie, Juexin; Wang, Xingming; Sheng, Guoying; Bi, Xinhui; Fu, Jiamo

    Tobacco smoking simulation experiment was conducted in a test room under different conditions such as cigarette brands, smoking number, and post-smoke decay in forced ventilation or in closed indoor environments. Thirty-seven chemical species were targeted and monitored, including volatile organic compounds (VOCs) and environmental tobacco smoke (ETS) markers. The results indicate that benzene, d-limonene, styrene, m-ethyltoluene and 1,2,4/1,3,5-trimethylbenzene are correlated well with ETS markers, but toluene, xylene, and ethylbenzene are not evidently correlated with ETS markers because there are some potential indoor sources of these compounds. 2,5-dimethylfuran is considered to be a better ETS marker due to the relative stability in different cigarette brands and a good relationship with other ETS markers. The VOCs concentrations emitted by tobacco smoking were linearly associated with the number of cigarettes consumed, and different behaviors were observed in closed indoor environment, of which ETS markers, d-limonene, styrene, trimethylbenzene, etc. decayed fast, whereas benzene, toluene, xylene, ethylbenzene, etc. decayed slowly and even increased in primary periods of the decay; hence ETS exposure in closed environments is believed to be more dangerous. VOCs concentrations and the relative percentage constituent of ETS markers of different brand cigarettes emissions vary largely, but the relative percentage constituent of ETS markers for the same brand cigarette emissions is similar.

  18. Proceedings of First International Workshop on Coping with Complexity. University of Bath 16-17th

    E-print Network

    Taleb-Bendiab, A.

    1 Proceedings of First International Workshop on Coping with Complexity. University of Bath 16-17th September 2004. ORGANISING COMMITTEE Anne Bruseberg, University of Bath Peter Johnson, University of Bath Peter J Wild, University of Bath #12;2 INTRODUCTION The use of interactive information and communication

  19. Organic geochemical studies of soils from the Rothamsted classical experiments — VI. The occurrence and source of organic acids in an experimental grassland soil

    Microsoft Academic Search

    Ian D. Bull; Chris J. Nott; Pim F. van Bergen; Paul R. Poulton; Richard P. Evershed

    2000-01-01

    Total lipid extracts (TLEs) of grass (aerial and sub-aerial, Holcus lanatus) from a plot on a long-term grassland experiment, and associated soil, along with the organic fraction of the TLE hydrolysates and the hydrolysates of the solvent extracted vegetation have been separated into fractions containing specific compound classes and analysed using gas chromatography (GC) and gas chromatography\\/mass spectrometry (GC\\/MS). The

  20. Organics.

    ERIC Educational Resources Information Center

    Chian, Edward S. K.; DeWalle, Foppe B.

    1978-01-01

    Presents water analysis literature for 1978. This review is concerned with organics, and it covers: (1) detergents and surfactants; (2) aliphatic and aromatic hydrocarbons; (3) pesticides and chlorinated hydrocarbons; and (4) naturally occurring organics. A list of 208 references is also presented. (HM)

  1. MATHEMATICAL MODEL OF PLANT UPTAKE AND TRANSLOCATION OF ORGANIC CHEMICALS: APPLICATION TO EXPERIMENTS

    EPA Science Inventory

    Uptake, transport, and accumulation of organic chemicals by plants are influenced by characteristics of the plant and properties of the chemical, soil, and environmental conditions. athematical model for uptake of organic chemicals by plants was calibrated by application to data ...

  2. Beyond heat baths: Generalized resource theories for small-scale thermodynamics

    E-print Network

    Nicole Yunger Halpern; Joseph M. Renes

    2014-09-13

    Small-scale heat exchanges have recently been modeled with resource theories intended to extend thermodynamics to the nanoscale and quantum regimes. We generalize these theories to exchanges of quantities other than heat, to baths other than heat baths, and to free energies other than the Helmholtz free energy. These generalizations are illustrated with "grand-potential" theories that model movements of heat and particles. Free operations include unitaries that conserve energy and particle number. From this conservation law and from resource-theory principles, the grand-canonical form of the free states is derived. States are shown to form a quasiorder characterized by free operations, d-majorization, the hypothesis-testing entropy, and rescaled Lorenz curves. We calculate the work distillable from, and we bound the work cost of creating, a state. These work quantities can differ but converge to the grand potential in the thermodynamic limit. Extending thermodynamic resource theories beyond heat baths, we open diverse realistic systems to modeling with one-shot statistical mechanics. Prospective applications such as electrochemical batteries are hoped to bridge one-shot theory to experiments.

  3. Using Artificial Soil and Dry-Column Flash Chromatography to Simulate Organic Substance Leaching Process: A Colorful Environmental Chemistry Experiment

    ERIC Educational Resources Information Center

    de Avellar, Isa G. J.; Cotta, Tais A. P. G.; Neder, Amarilis de V. Finageiv

    2012-01-01

    Soil is an important and complex environmental compartment and soil contamination contributes to the pollution of aquifers and other water basins. A simple and low-cost experiment is described in which the mobility of three organic compounds in an artificial soil is examined using dry-column flash chromatography. The compounds were applied on top…

  4. Synthesis of Di- and Trisubstituted Azulenes Using a Danheiser Annulation as the Key Step: An Advanced Organic Laboratory Experiment

    ERIC Educational Resources Information Center

    Thomas, Rebecca M.; Shea, Kevin M.

    2013-01-01

    This three-week advanced-level organic experiment provides students with an inquiry-based approach focused on learning traditional skills such as primary literature interpretation, reaction design, flash column chromatography, and NMR analysis. Additionally, students address higher-order concepts such as the origin of azulene's blue color,…

  5. The Self-Organizing System in Theory and Practice: The Experience of the Collaboratives for Humanities and Arts Teaching.

    ERIC Educational Resources Information Center

    Stanford, Barbara Dodds

    1996-01-01

    Educators participating in the Collaboratives for Humanities and Arts Instruction (CHART) network have found large domains of inquiry in which traditional models had little predictive value and bore little resemblance to experience. Self-organizing systems are open and interactive, have global properties flowing from individuals' aggregate…

  6. Inside the Black Box: Exploring the Value Added by Career and Technical Student Organizations to Students' High School Experience

    ERIC Educational Resources Information Center

    Alfeld, Corinne; Hansen, David M.; Aragon, Steven R.; Stone, James R., III

    2006-01-01

    This study explored the hypothesis that Career Technical Student Organizations (CTSOs) provide a variety of experiences that either directly or indirectly affect three important outcomes of secondary education: achievement, transition to postsecondary education and training, and employability. A pre-post-test comparison study of high school…

  7. Headspace GC-MS Analysis of Halogenated Volatile Organic Compounds in Aqueous Samples: An Experiment for General Chemistry Laboratory

    ERIC Educational Resources Information Center

    Keller, John W.; Fabbri, Cindy E.

    2012-01-01

    Analysis of halogenated volatile organic compounds (HVOCs) by GC-MS demonstrates the use of instrumentation in the environmental analysis of pollutant molecules and enhances student understanding of stable isotopes in nature. In this experiment, students separated and identified several HVOCs that have been implicated as industrial groundwater…

  8. The Dissection Room Experience: A Factor in the Choice of Organ and Whole Body Donation--A Nigerian Survey

    ERIC Educational Resources Information Center

    Anyanwu, Emeka G.; Obikili, Emmanuel N.; Agu, Augustine U.

    2014-01-01

    The psychosocial impact of human dissection on the lives of medical and health science students has been noted. To assess the impact of the dissection room experience on one's willingness to become a whole body and organ donor, the attitudes of 1,350 students and professionals from the medical, health, and non-health related disciplines to…

  9. A Multistep Organocatalysis Experiment for the Undergraduate Organic Laboratory: An Enantioselective Aldol Reaction Catalyzed by Methyl Prolinamide

    ERIC Educational Resources Information Center

    Wade, Edmir O.; Walsh, Kenneth E.

    2011-01-01

    In recent years, there has been an explosion of research concerning the area of organocatalysis. A multistep capstone laboratory project that combines traditional reactions frequently found in organic laboratory curriculums with this new field of research is described. In this experiment, the students synthesize a prolinamide-based organocatalyst…

  10. Planetary and Space Science 55 (2007) 383400 The ORGANICS experiment on BIOPAN V: UV and space exposure

    E-print Network

    2007-01-01

    ) on the EXPOSE facility on the International Space Station (ISS). For the small fluence that was collected during; International Space Station; Photo-stability 1. Introduction Carbon chemistry in space occurs most efficientlyPlanetary and Space Science 55 (2007) 383­400 The ORGANICS experiment on BIOPAN V: UV and space

  11. Microbiological Analysis in Three Diverse Natural Geothermal Bathing Pools in Iceland

    PubMed Central

    Thorolfsdottir, Berglind Osk Th.; Marteinsson, Viggo Thor

    2013-01-01

    Natural thermal bathing pools contain geothermal water that is very popular to bathe in but the water is not sterilized, irradiated or treated in any way. Increasing tourism in Iceland will lead to increasing numbers of bath guests, which can in turn affect the microbial flora in the pools and therefore user safety. Today, there is no legislation that applies to natural geothermal pools in Iceland, as the water is not used for consumption and the pools are not defined as public swimming pools. In this study, we conducted a microbiological analysis on three popular but different natural pools in Iceland, located at Lýsuhóll, Hveravellir and Landmannalaugar. Total bacterial counts were performed by flow cytometry, and with plate count at 22 °C, 37 °C and 50 °C. The presence of viable coliforms, Enterococcus spp. and pseudomonads were investigated by growth experiments on selective media. All samples were screened for noroviruses by real time PCR. The results indicate higher fecal contamination in the geothermal pools where the geothermal water flow was low and bathing guest count was high during the day. The number of cultivated Pseudomonas spp. was high (13,000–40,000 cfu/100 mL) in the natural pools, and several strains were isolated and classified as opportunistic pathogens. Norovirus was not detected in the three pools. DNA was extracted from one-liter samples in each pool and analyzed by partial 16S rRNA gene sequencing. Microbial diversity analysis revealed different microbial communities between the pools and they were primarily composed of alpha-, beta- and gammaproteobacteria. PMID:23493033

  12. Relation between creep compliance and elastic modulus in organic-rich shales observed through laboratory experiments.

    NASA Astrophysics Data System (ADS)

    Sone, Hiroki; Zoback, Mark

    2013-04-01

    We studied the ductile creep behavior of organic-rich shales from shale gas reservoirs in North America through laboratory triaxial experiments to better understand controls on the physical behavior of these rocks over time and the effect of creep on other rock properties. Laboratory experiments conducted at room-temperature conditions show that creep deformation observed at in-situ differential stress conditions is approximately linear with the applied differential pressure. The creep behavior is also anisotropic such that creep occurs more in the bedding-perpendicular direction than in the bedding-parallel direction. The reduction in sample volume during creep suggests that the creep is accommodated by a small amount of pore compaction occurring in the clay-aggregates and/or the relatively porous kerogen in the rock. Thus, the tendency to creep (creep compliance) is generally observed to increases with clay and kerogen volume. However, the strongest correlation is found between creep compliance and Young's modulus. A strong negative correlation between creep compliance and elastic Young's modulus exists regardless of the sample orientation and despite the wide range of sample mineralogy (5-50% clay, 5-60% quartz-feldspar-pyrite, 0-80% carbonates). This correlation is quite interesting as inelastic creep and elastic stiffness depend on somewhat different physical attributes. We attempt to quantitatively explain the correlation between creep behavior and elastic stiffness by appealing to a stress-partitioning that occurs between the soft components (clay and kerogen) and stiff components (quartz, feldspar, pyrite, carbonates) of the shale rock. First, the stress-partitioning occurring within the soft and stiff components is quantified based on the rock composition, elastic properties of the individual components, and the overall average Young's modulus of the rock. By combining the stress-partitioning behavior with knowledge that the creep behavior is linear against the applied stress, we forward calculate the creep compliance of the whole rock. Results show that when creep is linear against stress, a unique relation between creep compliance and elastic modulus can be established for rocks with similar mineral assemblages, consistent with our laboratory results. Thus, our results provide insights into how creep behaviors of poly-mineralic rocks can be re-constructed from the creep properties of the individual phases composing the rock.

  13. T-1025 IU SciBath-768 detector tests in MI-12

    SciTech Connect

    Tayloe, Rex; Cooper, R.; Garrison, L.; Thornton, T.; Rebenitsch, L.; /Indiana U.; DeJongh, Fritz; Loer, Benjamin; Ramberg, Erik; Yoo, Jonghee; /Fermilab

    2012-02-11

    This is a memorandum of understanding between the Fermi National Accelerator Laboratory (Fermilab) and the experimenters of Department of Physics and Center for Exploration of Energy and Matter, Indiana University, who have committed to participate in detector tests to be carried out during the 2012 Fermilab Neutrino program. The memorandum is intended solely for the purpose of recording expectations for budget estimates and work allocations for Fermilab, the funding agencies and the participating institutions. it reflects an arrangement that currently is satisfactory to the parties; however, it is recognized and anticipated that changing circumstances of the evolving research program will necessitate revisions. The parties agree to modify this memorandum to reflect such required adjustments. Actual contractual obligations will be set forth in separate documents. The experimenters propsoe to test their prototype 'SciBat-768' detector in the MI-12 building for 3 months (February-April) in Spring 2012. The major goal of this effort is to measure or limit the flux of beam-induced neutrons in a far-off-axis (> 45{sup o}) location of the Booster Neutrino Beamline (BNB). This flux is of interest for a proposed coherent neutral-current neutrino-argon elastic scattering experiment. A second goal is to collect more test data for the SciBath-768 to enable better understanding and calibration of the device. The SciBath-768 detector successfully ran for 3 months in the MINOS Underground Area in Fall 2011 as testbeam experiment T-1014 and is currently running above ground in the MINOS service building. For the run proposed here, the experiments are requesting: space in MI-12 in which to run the SciBath detector during February-April 2012 while the BNB is operating; technical support to help with moving the equipment on site; access to power, internet, and accelerator signals; and a small office space from which to run and monitor the experiment.

  14. Review Article: Persistent organic pollutants and landfills - a review of past experiences and future challenges.

    PubMed

    Weber, Roland; Watson, Alan; Forter, Martin; Oliaei, Fardin

    2011-01-01

    The landfilling and dumping of persistent organic pollutants (POPs) and other persistent hazardous compounds, such as polychlorinated biphenyls (PCBs), hexachlorocyclohaxane (HCH), polybrominated diphenylether (PBDEs) or perfluorooctane sulfonic acid (PFOS) can have significant adverse environmental consequences. This paper reviews past experiences with such disposal practices and highlights their unsustainability due to the risks of contamination of ecosystems, the food chain, together with ground and drinking water supplies. The use and associated disposal of POPs have been occurring for over 50 years. Concurrent with the phase-out of some of the most hazardous chemicals, the production of new POPs, such as brominated and fluorinated compounds has increased since the 1990s. These latter compounds are commonly used in a wide range of consumer goods, and as consumer products reach the end of their useful lives, ultimately enter waste recycling and disposal systems, in particular at municipal landfills. Because of their very slow, or lack of degradability, POPs will persist in landfills for many decades and possibly centuries. Over these extended time periods engineered landfill systems and their liners are likely to degrade, thus posing a contemporary and future risk of releasing large contaminant loads to the environment. This review highlights the necessity for alternative disposal methods for POP wastes, including destruction or complete removal from potential environmental release. In addition to such end of pipe solutions a policy change in the use pattern of persistent toxic chemicals is inevitable. In addition, inventories for the location and quantity of POPs in landfills, together with an assessment of their threat to ecosystems, drinking water and food resources are identified as key measures to facilitate appropriate management of risks. Finally the challenges of POP wastes in transition/developing countries, the risk of increased leaching of POPs from landfills due to climate change, and the possible negative impact of natural attenuation processes are considered. PMID:21224404

  15. Exploring Atmospheric Aqueous Chemistry (and Secondary Organic Aerosol Formation) through OH Radical Oxidation Experiments, Droplet Evaporation and Chemical Modeling

    NASA Astrophysics Data System (ADS)

    Turpin, B. J.; Kirkland, J. R.; Lim, Y. B.; Ortiz-Montalvo, D. L.; Sullivan, A.; Häkkinen, S.; Schwier, A. N.; Tan, Y.; McNeill, V. F.; Collett, J. L.; Skog, K.; Keutsch, F. N.; Sareen, N.; Carlton, A. G.; Decesari, S.; Facchini, C.

    2013-12-01

    Gas phase photochemistry fragments and oxidizes organic emissions, making water-soluble organics ubiquitous in the atmosphere. My group and others have found that several water-soluble compounds react further in the aqueous phase forming low volatility products under atmospherically-relevant conditions (i.e., in clouds, fogs and wet aerosols). Thus, secondary organic aerosol can form as a result of gas followed by aqueous chemistry (aqSOA). We have used aqueous OH radical oxidation experiments coupled with product analysis and chemical modeling to validate and refine the aqueous chemistry of glyoxal, methylglyoxal, glycolaldehyde, and acetic acid. The resulting chemical model has provided insights into the differences between oxidation chemistry in clouds and in wet aerosols. Further, we conducted droplet evaporation experiments to characterize the volatility of the products. Most recently, we have conducted aqueous OH radical oxidation experiments with ambient mixtures of water-soluble gases to identify additional atmospherically-important precursors and products. Specifically, we scrubbed water-soluble gases from the ambient air in the Po Valley, Italy using four mist chambers in parallel, operating at 25-30 L min-1. Aqueous OH radical oxidation experiments and control experiments were conducted with these mixtures (total organic carbon ? 100 ?M-C). OH radicals (3.5E-2 ?M [OH] s-1) were generated by photolyzing H2O2. Precursors and products were characterized using electrospray ionization mass spectrometry (ESI-MS), ion chromatography (IC), IC-ESI-MS, and ultra high resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). Chemical modeling suggests that organic acids (e.g., oxalate, pyruvate, glycolate) are major products of OH radical oxidation at cloud-relevant concentrations, whereas organic radical - radical reactions result in the formation of oligomers in wet aerosols. Products of cloud chemistry and droplet evaporation have effective vapor pressures that are orders of magnitude lower when ammonium hydroxide is present (pH 7) than without (at lower pH). In Po Valley experiments, nitrogen-containing organics were prominent precursors and intermediates. Pyruvate and oxalate were among the products. Importantly, formation of aqSOA helps to explain the high O/C ratios found in atmospheric aerosols. While uncertainties remain large, global modeling suggests that aqSOA is comparable in magnitude to SOA formed through gas phase chemistry and vapor pressure driven partitioning (gasSOA).

  16. Bath salts: they are not what you think.

    PubMed

    Wieland, Diane M; Halter, Margaret J; Levine, Ciara

    2012-02-01

    Psychoactive bath salts are a relatively new group of designer drugs sold as tablets, capsules, or powder and pur-chased in places such as tobacco and convenience stores, gas stations, head shops, and the Internet. Bath salts are stimulant agents that mimic cocaine,lysergic acid diethylamide, methamphetamine, or methylenedioxymethamphetamine (ecstasy). The most common bath salts are the cathinone derivatives 3,4-methylenedioxypyrovalerone(MDPV), 4-methylmethcathinone(mephedrone), and 3,4-methylenedioxy-N-methylcathinone (methylone). The drugs cause intense stimulation, eu-phoria, elevated mood, and a pleasurable "rush" Tachycardia, hypertension,peripheral constriction, chest pain, hallucinations, paranoia, erratic behavior,inattention, lack of memory of substance use, and psychosis have been observed in those who have used bath salts. The U.S. Drug Enforcement Administration recently exercised an emergency authority to name three key ingredients in bath salts as Schedule I, thereby making them illegal to possess or sell in the United States. Nursing implications related to both clinical and educational settings are discussed. PMID:22439144

  17. Large-time evolution of an electron in photon bath

    SciTech Connect

    Kazakov, Kirill A.; Nikitin, Vladimir V., E-mail: markiz4@yandex.ru

    2012-12-15

    The problem of infrared divergence of the effective electromagnetic field produced by elementary charges is revisited using the model of an electron freely evolving in a photon bath. It is shown that for any finite travel time, the effective field of the electron is infrared-finite, and that at each order of perturbation theory the radiative contributions grow unboundedly with time. Using the Schwinger-Keldysh formalism, factorization of divergent contributions in multi-loop diagrams is proved, and summation of the resulting infinite series is performed. It is found that despite the unbounded growth of individual contributions to the effective field, their sum is bounded, tending to zero in the limit of infinite travel time. It is concluded that the physical meaning of infrared singularity in the effective field is the existence of a peculiar irreversible spreading of electric charges, caused by their interaction with the electromagnetic field. This spreading originates from the quantum electromagnetic fluctuations, rather than the electron-photon scattering, and exists in vacuum as well as at finite temperatures. It shows itself in a damping of the off-diagonal elements of the momentum-space density matrix of electron, but does not affect its momentum probability distribution. This effect is discussed in terms of thermalization of the electron state, and the asymptotic growth of its quantum entropy is determined. Relationship of the obtained results to the Bloch-Nordsieck theorem is established and considered from the standpoint of measurability of the electromagnetic field. The effect of irreversible spreading on the electron diffraction in the classic two-slit experiment is determined, and is shown to be detectable in principle by modern devices already at room temperature. - Highlights: Black-Right-Pointing-Pointer Infrared finiteness of the effective electromagnetic field of a free electron is proved. Black-Right-Pointing-Pointer Quantum radiative effects result in an irreversible spreading of free electrons. Black-Right-Pointing-Pointer The irreversible spreading produces a detectable effect on the electron interference.

  18. Can organic farming help to reduce N-losses? Experiences from Denmark

    Microsoft Academic Search

    Tommy Dalgaard; Niels Halberg; Ib Sillebak Kristensen

    Abstract This study is in two parts. In the first part, nitrogen (N) losses per unit of milk and meat in Danish conventional and organic pig and dairy farming were compared on the basis of farm data. In the second part, organic and conventional dairy farming were compared in detail, using modelling. N-surpluses at different livestock densities, fodder intensities, and

  19. Bathing waters: new directive, new standards, new quality approach.

    PubMed

    Mansilha, Catarina R; Coelho, Carla A; Heitor, Ana M; Amado, João; Martins, Joaquim P; Gameiro, Paula

    2009-10-01

    Bathing water quality is an important public health issue, mainly because of fecal contamination. In 2006, the European Commission (EC) adopted a new directive with respect to recreational bathing waters that calls for stricter standards and reduces the number of laboratory tests done in routine beach monitoring from nineteen to two bacterial indicators, namely, Escherichia coli and intestinal enterococci, replacing policies of the EC Bathing Water Directive that have existed since 1976. Our practice in Portugal is in line with this international development, and this study demonstrates the equivalency of the new bacteriological parameters with the old. The water quality of 25 coastal beaches was surveyed using both new and old microbiological indicators of fecal contamination. Statistical analysis demonstrated equivalency of the results obtained for fecal coliforms with Escherichia coli and for fecal streptococci with intestinal enterococci. PMID:19732913

  20. Production of aqueous spherical gold nanoparticles using conventional ultrasonic bath

    PubMed Central

    2012-01-01

    A conventional ultrasonic bath was used to examine the feasibility of forming aqueous spherical gold nanoparticles (GNPs) under atmospheric conditions. The effects of ultrasonic energy on the size and morphology of GNPs were also investigated. Highly monodispersed spherical GNPs were successfully synthesised by sodium citrate reduction in a conventional ultrasonic bath, without an additional heater or magnetic stirrer, as evidenced by ultraviolet–visible spectra and transmission electron microscopy. Ultrasonic energy was shown to be a key parameter for producing spherical GNPs of tunable sizes (20 to 50?nm). A proposed scheme for understanding the role of ultrasonic energy in the formation and growth of GNPs was discussed. The simple single-step method using just a conventional ultrasonic bath as demonstrated in this study offers new opportunities in the production of aqueous suspensions of monodispersed spherical GNPs. PMID:22839598

  1. Entanglement sharing and decoherence in the spin-bath

    SciTech Connect

    Dawson, Christopher M.; McKenzie, Ross H. [School of Physical Sciences, University of Queensland, St Lucia, QLD 4072 (Australia); Hines, Andrew P.; Milburn, G.J. [Centre for Quantum Computer Technology, The University of Queensland, St Lucia, QLD 4072 (Australia); School of Physical Sciences, University of Queensland, St Lucia, QLD 4072 (Australia)

    2005-05-15

    The monogamous nature of entanglement has been illustrated by the derivation of entanglement-sharing inequalities--bounds on the amount of entanglement that can be shared among the various parts of a multipartite system. Motivated by recent studies of decoherence, we demonstrate an interesting manifestation of this phenomena that arises in system-environment models where there exists interactions between the modes or subsystems of the environment. We investigate this phenomenon in the spin-bath environment, constructing an entanglement-sharing inequality bounding the entanglement between a central spin and the environment in terms of the pairwise entanglement between individual bath spins. The relation of this result to decoherence will be illustrated using simplified system-bath models of decoherence.

  2. Generation of a bubble universe using a negative energy bath

    E-print Network

    Dong-il Hwang; Dong-han Yeom

    2011-06-28

    This paper suggests a model for a bubble universe using buildable false vacuum bubbles. We study the causal structures of collapsing false vacuum bubbles using double-null simulations. False vacuum bubbles violate the null energy condition and emit negative energy along the outgoing direction through semi-classical effects. If there are a few collapsing false vacuum bubbles and they emit negative energy to a certain region, then the region can be approximated by a negative energy bath, which means the region is homogeneously filled by negative energy. If a false vacuum bubble is generated in the negative energy bath and the tension of the bubble effectively becomes negative in the bath, then the bubble can expand and form an inflating bubble universe. This scenario uses a set of assumptions different from those in previous studies because it does not require tunneling to unbuildable bubbles.

  3. Generation of a bubble universe using a negative energy bath

    E-print Network

    Hwang, Dong-il

    2010-01-01

    In this paper, we suggest a model for a bubble universe using buildable false vacuum bubbles. We study causal structures of collapsing false vacuum bubbles using double-null simulations. False vacuum bubbles violate the null energy condition and emit negative energy along the outgoing direction via semi-classical effects. If there are a few collapsing false vacuum bubbles and they emit negative energy to a certain region, then the region can be approximated by a negative energy bath, that means the region is homogeneously filled by negative energy. If a false vacuum bubble is generated in the negative energy bath and the tension of the bubble effectively becomes negative in the bath, then the bubble can expand and form an inflating bubble universe. This scenario is weaker than previous authors' assumptions because we do not require tunneling to unbuildable bubbles. Finally, we summarize potential problems to realize this scenario.

  4. Reduced quantum dynamics with arbitrary bath spectral densities: Hierarchical equations of motion based on several different bath decomposition schemes

    SciTech Connect

    Liu, Hao; Zhu, Lili; Bai, Shuming; Shi, Qiang, E-mail: qshi@iccas.ac.cn [Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Beijing 100190 (China)] [Beijing National Laboratory for Molecular Sciences, State Key Laboratory for Structural Chemistry of Unstable and Stable Species, Institute of Chemistry, Chinese Academy of Sciences, Zhongguancun, Beijing 100190 (China)

    2014-04-07

    We investigated applications of the hierarchical equation of motion (HEOM) method to perform high order perturbation calculations of reduced quantum dynamics for a harmonic bath with arbitrary spectral densities. Three different schemes are used to decompose the bath spectral density into analytical forms that are suitable to the HEOM treatment: (1) The multiple Lorentzian mode model that can be obtained by numerically fitting the model spectral density. (2) The combined Debye and oscillatory Debye modes model that can be constructed by fitting the corresponding classical bath correlation function. (3) A new method that uses undamped harmonic oscillator modes explicitly in the HEOM formalism. Methods to extract system-bath correlations were investigated for the above bath decomposition schemes. We also show that HEOM in the undamped harmonic oscillator modes can give detailed information on the partial Wigner transform of the total density operator. Theoretical analysis and numerical simulations of the spin-Boson dynamics and the absorption line shape of molecular dimers show that the HEOM formalism for high order perturbations can serve as an important tool in studying the quantum dissipative dynamics in the intermediate coupling regime.

  5. Quantum energy and coherence exchange with discrete baths

    NASA Astrophysics Data System (ADS)

    Galiceanu, M.; Beims, M. W.; Strunz, W. T.

    2014-12-01

    Coherence and quantum average energy exchange are studied for a system particle as a function of the number N of constituents of a discrete bath model. The time evolution of the energy and coherence, determined via the system purity (proportional to the linear entropy of the quantum statistical ensemble), are obtained solving numerically the Schrödinger equation. A new simplified stochastic Schrödinger equation is derived which takes into account the discreteness of the bath. The environment (bath) is composed of a finite number N of uncoupled harmonic oscillators (HOs), characterizing a structured bath, for which a non-Markovian behavior is expected. Two distinct physical situations are assumed for the system particle: the HO and the Morse potential. In the limit N?? the bath is assumed to have an ohmic, sub-ohmic or super-ohmic spectral density. In the case of the HO, for very low values of N (?10) the mean energy and purity oscillate between HO and bath indefinitely in time, while for intermediate and larger values (N?10?500) they start to decay with two distinct time regimes: exponential for relatively short times and power-law for larger times. In the case of the Morse potential we only observe an exponential decay for large values of N while for small N’s, due to the anharmonicity of the potential, no recurrences of the mean energy and coherences are observed. Wave packet dynamics is used to determine the evolution of the particle inside the system potentials. For both systems the time behavior of a non-Markovianity measure is analyzed as a function of N and is shown to be directly related to the time behavior of the purity.

  6. Planar saline bath phantom of the Rush head model.

    PubMed

    Shephard, Clarissa; Jochum, Thomas; Abzug, Zachary; Wolf, Patrick

    2011-01-01

    The Rush head model is an approximation of the volume conducting properties of the human head. A planar saline bath phantom was developed to simulate the key properties of the Rush head model while creating a testing platform for implantable neural devices. The phantom closely mimics electrical properties of human tissue such as increased resistivity through the skull region and current flow that wraps around the head. Preliminary testing shows good agreement of the saline bath phantom to predictions from a computer model. PMID:22256016

  7. Environmental factors and the development of Bath Spa, England

    NASA Astrophysics Data System (ADS)

    Kellaway, G. A.

    1994-10-01

    Thermal water springs at Bristol and Bath in west England have come under close scrutiny since the closure of Bath Spa in 1978. In order to protect the hot springs from dewatering and loss of pressure due to largescale quarrying and deep drilling, it is necessary to identify the sources and routes whereby the thermal water travels to its resurgences in the Avon valley. Control over deep water movements is exercised by the structure and size of the aquifers and aquicludes, modified by zones of Quaternary—Recent fracturing along which water movements have not been restricted or blocked by mineralization.

  8. Black nickel electrodeposition from a modified Watts bath

    Microsoft Academic Search

    Magdy A. M. Ibrahim

    2006-01-01

    Black nickel coatings were electrodeposited on to steel substrates from a Watts bath containing potassium nitrate. The best\\u000a operating conditions necessary to produce smooth and highly adherent black nickel were found to be NiSO4 ? 6H2O 0.63 M, NiCl2 ? 6H2O 0.09 M, H3BO3 0.3 M and KNO3 0.2 M at pH of 4.6, i=0.5 A dm?2, T=25 ?C and t=10 min. The modified Watts bath has a throwing power (TP) of

  9. Representing Cardiac Bidomain Bath-Loading Effects by an Augmented Monodomain Approach: Application to Complex Ventricular Models

    PubMed Central

    2011-01-01

    Although the cardiac bidomain model has been widely used in the simulation of electrical activation, its relatively computationally expensive nature means that monodomain approaches are generally required for long duration simulations (for example, investigations of arrhythmia mechanisms). However, the presence of a conducting bath surrounding the tissue is known to induce wavefront curvature (surface leading bulk), a phenomena absent in standard monodomain approaches. Here, we investigate the biophysical origin of the bidomain bath-loading induced wavefront curvature and present a novel augmented monodomain equivalent bidomain approach faithfully replicating all aspects of bidomain wavefront morphology and conduction velocity, but with a fraction of the computational cost. Bath-loading effects are shown to be highly dependent upon specific conductivity parameters, but less dependent upon the thickness or conductivity of the surrounding bath, with even relatively thin surrounding fluid layers (~ 0.1 mm) producing significant wavefront curvature in bidomain simulations. We demonstrate that our augmented monodomain approach can be easily adapted for different conductivity sets and applied to anatomically complex models thus facilitating fast and accurate simulation of cardiac wavefront dynamics during long duration simulations, further aiding the faithful comparison of simulations with experiments. PMID:21292591

  10. Diels-Alder Cycloadditions: A MORE Experiment in the Organic Laboratory Including a Diene Identification Exercise Involving NMR Spectroscopy and Molecular Modeling

    ERIC Educational Resources Information Center

    Shaw, Roosevelt; Severin, Ashika; Balfour, Miguel; Nettles, Columbus

    2005-01-01

    Two Diels-Alder reactions are described that are suitable for a MORE (microwave-induced organic reaction enhanced) experiment in the organic chemistry laboratory course. A second experiment in which the splitting patterns of the vinyl protons in the nuclear magnetic resonance (NMR) spectra of two MORE adducts are used in conjunction with molecular…

  11. The Teaching of Organic Chemistry in Schools--Can We Learn from the Kenyan Experience?

    ERIC Educational Resources Information Center

    Brook, David W.

    1988-01-01

    Describes a study of perceived difficulty of chemistry courses among secondary school and college students in Kenya. Concludes that organic chemistry may not be as difficult as many people believe. (CW)

  12. Knowledge sharing within organizations: linking art, theory, scenarios and professional experience

    NASA Technical Reports Server (NTRS)

    Bailey, T.; Burton, Y. C.

    2000-01-01

    In this discussion, T. Bailey will be addressing the multiple paradigms within organizations using imagery. Dr. Burton will discuss the relationship between these paradigms and social exchanges that lead to knowledge sharing.

  13. Early visual experience and the receptive-field organization of optic flow processing interneurons in the fly motion pathway

    Microsoft Academic Search

    Katja Karmeier; Rico Tabor; Holger G. Karmeier

    2006-01-01

    Abstract The distribution of local preferred directions and motion sensitivities within the receptive fields of so-called tangential neurons,in the fly visual system,was previously found to match optic flow fields as induced by certain self-motions. The complex,receptive-field organization of the tangential neurons,and the recent evidence showing,that the orderly development,of the fly's peripheral visual system,depends,on visual experience led us to investigate whether

  14. Clostridium difficile Colitis in Solid Organ Transplantation—A Single-Center Experience

    Microsoft Academic Search

    I. Stelzmueller; H. Goegele; M. Biebl; S. Wiesmayr; N. Berger; W. Tabarelli; E. Ruttmann; J. Albright; R. Margreiter; M. Fille; H. Bonatti

    2007-01-01

    Clostridium difficile (CD) is one of the most common causes of diarrhea in solid organ transplantation (SOT). Between 1996 and 2005, a total of\\u000a 2474 solid organ transplants were performed at our institution, of which 43 patients developed CD-associated diarrhea. There\\u000a were 3 lung, 3 heart, 20 liver, 8 kidney-pancreas, 6 kidney, 1 composite tissue, and 2 multivisceral recipients. Onset

  15. Microcosm experiments to control anaerobic redox conditions when studying the fate of organic micropollutants in aquifer material

    NASA Astrophysics Data System (ADS)

    Barbieri, Manuela; Carrera, Jesús; Sanchez-Vila, Xavier; Ayora, Carlos; Cama, Jordi; Köck-Schulmeyer, Marianne; López de Alda, Miren; Barceló, Damià; Tobella Brunet, Joana; Hernández García, Marta

    2011-11-01

    The natural processes occurring in subsurface environments have proven to effectively remove a number of organic pollutants from water. The predominant redox conditions revealed to be one of the controlling factors. However, in the case of organic micropollutants the knowledge on this potential redox-dependent behavior is still limited. Motivated by managed aquifer recharge practices microcosm experiments involving aquifer material, settings potentially feasible in field applications, and organic micropollutants at environmental concentrations were carried out. Different anaerobic redox conditions were promoted and sustained in each set of microcosms by adding adequate quantities of electron donors and acceptors. Whereas denitrification and sulfate-reducing conditions are easily achieved and maintained, Fe- and Mn-reduction are strongly constrained by the slower dissolution of the solid phases commonly present in aquifers. The thorough description and numerical modeling of the evolution of the experiments, including major and trace solutes and dissolution/precipitation of solid phases, have been proven necessary to the understanding of the processes and closing the mass balance. As an example of micropollutant results, the ubiquitous beta-blocker atenolol is completely removed in the experiments, the removal occurring faster under more advanced redox conditions. This suggests that aquifers constitute a potentially efficient alternative water treatment for atenolol, especially if adequate redox conditions are promoted during recharge and long enough residence times are ensured.

  16. Composition, dynamics, and fate of leached dissolved organic matter in terrestrial ecosystems: Results from a decomposition experiment

    USGS Publications Warehouse

    Cleveland, C.C.; Neff, J.C.; Townsend, A.R.; Hood, E.

    2004-01-01

    Fluxes of dissolved organic matter (DOM) are an important vector for the movement of carbon (C) and nutrients both within and between ecosystems. However, although DOM fluxes from throughfall and through litterfall can be large, little is known about the fate of DOM leached from plant canopies, or from the litter layer into the soil horizon. In this study, our objectives were to determine the importance of plant-litter leachate as a vehicle for DOM movement, and to track DOM decomposition [including dissolve organic carbon (DOC) and dissolved organic nitrogen (DON) fractions], as well as DOM chemical and isotopic dynamics, during a long-term laboratory incubation experiment using fresh leaves and litter from several ecosystem types. The water-extractable fraction of organic C was high for all five plant species, as was the biodegradable fraction; in most cases, more than 70% of the initial DOM was decomposed in the first 10 days of the experiment. The chemical composition of the DOM changed as decomposition proceeded, with humic (hydrophobic) fractions becoming relatively more abundant than nonhumic (hydrophilic) fractions over time. However, in spite of proportional changes in humic and nonhumic fractions over time, our data suggest that both fractions are readily decomposed in the absence of physicochemical reactions with soil surfaces. Our data also showed no changes in the ??13C signature of DOM during decomposition, suggesting that isotopic fractionation during DOM uptake is not a significant process. These results suggest that soil microorganisms preferentially decompose more labile organic molecules in the DOM pool, which also tend to be isotopically heavier than more recalcitrant DOM fractions. We believe that the interaction between DOM decomposition dynamics and soil sorption processes contribute to the ??13C enrichment of soil organic matter commonly observed with depth in soil profiles.

  17. 19. VIEW OF THE PLATING BATHS AND CONTROL PANELS. GOLD ...

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

    19. VIEW OF THE PLATING BATHS AND CONTROL PANELS. GOLD AND SILVER WERE AMONG THE MATERIALS PLATED ONTO PARTS MADE OF COPPER, STAINLESS STEEL AND STEEL. (11/15/89) - Rocky Flats Plant, Non-Nuclear Production Facility, South of Cottonwood Avenue, west of Seventh Avenue & east of Building 460, Golden, Jefferson County, CO

  18. MASTER BATH SHOWING SINK WITH VANITY AND THE MEDICINE CABINET. ...

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

    MASTER BATH SHOWING SINK WITH VANITY AND THE MEDICINE CABINET. VIEW FACING WEST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, U-Shaped Two-Bedroom Single-Family Type 6, Birch Circle, Elm Drive, Elm Circle, and Date Drive, Pearl City, Honolulu County, HI

  19. Interior detail of unit "A" bath showing original medicine cabinet, ...

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

    Interior detail of unit "A" bath showing original medicine cabinet, ceramic soap dishes, ceramic towel rod, and triangular motif on ceramic features, facing south. - Albrook Air Force Station, Non-Commissioned Officers' Duplex, East side of Hall Street, Balboa, Former Panama Canal Zone, CZ

  20. MASTER BATH SHOWING THE LINEN CLOSET WITH BUILTIN SHELVES. NOTE ...

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

    MASTER BATH SHOWING THE LINEN CLOSET WITH BUILT-IN SHELVES. NOTE THE WINDOWS IN THE UPPER PORTION OF THE EXTERIOR WALL. VIEW FACING NORTHWEST - Camp H.M. Smith and Navy Public Works Center Manana Title VII (Capehart) Housing, U-Shaped Two-Bedroom Duplex Type 1, Acacia Road, Birch Circle, and Cedar Drive, Pearl City, Honolulu County, HI

  1. Electron spin decoherence in nuclear spin baths and dynamical decoupling

    SciTech Connect

    Zhao, N.; Yang, W.; Ho, S. W.; Hu, J. L.; Wan, J. T. K.; Liu, R. B. [Department of Physics, Chinese University of Hong Kong, Shatin, New Territories (Hong Kong)

    2011-12-23

    We introduce the quantum theory of the electron spin decoherence in a nuclear spin bath and the dynamical decoupling approach for protecting the electron spin coherence. These theories are applied to various solid-state systems, such as radical spins in molecular crystals and NV centers in diamond.

  2. 9. VIEW OF MOLTEN SALT BATH EQUIPMENT AND ROLLER PRESSES ...

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

    9. VIEW OF MOLTEN SALT BATH EQUIPMENT AND ROLLER PRESSES BEING INSTALLED ON THE WEST SIDE (SIDE B) OF BUILDING 883. SIDE B OF BUILDING 883 WAS USED TO PROCESS ENRICHED URANIUM FROM 1957-66. (1/23/57) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

  3. 13. VIEW OF THE MOLTEN SALT BATHS USED TO UNIFORMLY ...

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

    13. VIEW OF THE MOLTEN SALT BATHS USED TO UNIFORMLY AND QUICKLY HEAT METALS PRIOR TO WORKING (ROLLING). (9/16/85) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

  4. VIEW OF INTEGRITY TESTING EQUIPMENT UTILIZING CRYOGENIC BATHS IN BUILDING ...

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

    VIEW OF INTEGRITY TESTING EQUIPMENT UTILIZING CRYOGENIC BATHS IN BUILDING 991. (6/7/68) - Rocky Flats Plant, Final Assembly & Shipping, Eastern portion of plant site, south of Spruce Avenue, east of Tenth Street & north of Central Avenue, Golden, Jefferson County, CO

  5. Results of Computer Assisted Instruction at Bath Elementary School.

    ERIC Educational Resources Information Center

    Martha Holden Jennings Foundation, Cleveland, OH.

    This pilot project at Bath Elementary School at Richfield, Ohio, was conducted to assess the feasibility of computer assisted instruction (CAI) for the Revere Local Elementary Schools. The primary focus of the project was to assist sixth grade students in using the computer as an interactive instructional system in the areas of remedial reading,…

  6. Gyroscopically Stabilized Oscillators and Heat Baths Anthony M. Bloch

    E-print Network

    Bloch, Anthony

    Gyroscopically Stabilized Oscillators and Heat Baths Anthony M. Bloch #3; Department of Mathematics@research.bell-labs.com November 25, 2003 Abstract In this paper we analyze the stability of a gyroscopic oscillator interacting a #12;nite gyroscopic oscillator model of a particle on a rotating disc and a particle in a magnetic #12

  7. Neurochemical organization and experience-dependent activation of estrogen-associated circuits in the songbird auditory forebrain.

    PubMed

    Jeong, Jin Kwon; Burrows, Kaiping; Tremere, Liisa A; Pinaud, Raphael

    2011-07-01

    The classic steroid hormone estradiol is rapidly produced by central auditory neurons in the songbird brain and instantaneously modulates auditory coding to enhance the neural and behavioral discrimination of acoustic signals. Although recent advances highlight novel roles for estradiol in the regulation of central auditory processing, current knowledge on the functional and neurochemical organization of estrogen-associated circuits, as well as the impact of sensory experience in these auditory forebrain networks, remains very limited. Here we show that both estrogen-producing and -sensitive neurons are highly expressed in the caudomedial nidopallium (NCM), the zebra finch analog of the mammalian auditory association cortex, but not other auditory forebrain areas. We further demonstrate that auditory experience primarily engages estrogen-producing, and to a lesser extent, estrogen-responsive neurons in NCM, that these neuronal populations moderately overlap and that acute episodes of sensory experience do not quantitatively affect these circuits. Finally, we show that whereas estrogen-producing cells are neurochemically heterogeneous, estrogen-sensitive neurons are primarily glutamatergic. These findings reveal the neurochemical and functional organization of estrogen-associated circuits in the auditory forebrain, demonstrate their activation and stability in response to sensory experience in behaving animals, and highlight estrogenic circuits as fundamental components of central networks supporting sensory processing. PMID:21707790

  8. Neurochemical Organization and Experience-Dependent Activation of Estrogen-Associated Circuits in the Songbird Auditory Forebrain

    PubMed Central

    Jeong, Jin Kwon; Burrows, Kaiping; Tremere, Liisa A.; Pinaud, Raphael

    2011-01-01

    The classic steroid hormone estradiol is rapidly produced by central auditory neurons in the songbird brain and instantaneously modulates auditory coding to enhance the neural and behavioral discrimination of acoustic signals. Although these recent advances highlight novel roles for estradiol in the regulation of central auditory processing, current knowledge on the functional and neurochemical organization of estrogen-associated circuits, as well as the impact of sensory experience in these auditory forebrain networks, remains very limited. Here we show that both estrogen-producing and -sensitive neurons are highly expressed in the caudomedial nidopallium (NCM), the zebra finch analog of the mammalian auditory association cortex, but not other auditory forebrain areas. We further demonstrate that auditory experience primarily engages estrogen-producing, and to a lesser extent, estrogen-responsive neurons in NCM, that these neuronal populations moderately overlap, and that acute episodes of sensory experience do not quantitatively affect these circuits. Finally, we show that whereas estrogen-producing cells are neurochemically heterogenous, estrogen-sensitive neurons are primarily glutamatergic. These findings reveal the neurochemical and functional organization of estrogen-associated circuits in the auditory forebrain, demonstrate their activation and stability in response to sensory experience in behaving animals, and highlight estrogenic circuits as fundamental components of central networks supporting sensory processing. PMID:21707790

  9. Bath Stone - a Possible Global Heritage Stone from England

    NASA Astrophysics Data System (ADS)

    Marker, Brian

    2014-05-01

    The Middle Jurassic strata of England have several horizons of oolitic and bioclastic limestones that provide high quality dimension stone. One of the most important is found in and near the City of Bath. The Great Oolite Group (Upper Bathonian) contains the Combe Down and Bath Oolites, consisting of current bedded oolites and shelly oolites, that have been used extensively as freestones for construction nearby, for prestigious buildings through much of southern England and more widely. The stone has been used to some extent since Roman times when the city, then known as Aquae Sulis, was an important hot spa. The stone was used to a limited extent through medieval times but from the early 18th century onwards was exploited on a large scale through surface quarrying and underground mining. The City was extensively redeveloped in the 18th to early 19th century, mostly using Bath Stone, when the spas made it a fashionable resort. Buildings from that period include architectural "gems" such as the Royal Crescent and Pulteney Bridge, as well as the renovated Roman Baths. Many buildings were designed by some of the foremost British architects of the time. The consistent use of this stone gives the City an architectural integrity throughout. These features led to the designation of the City as a World Heritage Site. It is a requirement in current City planning policy documents that Bath Stone should be used for new building to preserve the appearance of the City. More widely the stone was used in major houses (e.g. Buckingham Palace and Apsley House in London; King's Pavilion in Brighton); civic buildings (e.g. Bristol Guildhall; Dartmouth Naval College in Devon); churches and cathedrals (e.g. Truro Cathedral in Cornwall); and engineered structures (e.g. the large Dundas Aqueduct on the Kennet and Avon Canal). More widely, Bath Stone has been used in Union Station in Washington DC; Toronto Bible College and the Town Hall at Cape Town, South Africa. Extraction declined in the late 20th century but several quarries and underground mines remain operational providing stone for the local market, repair and maintenance of historic buildings and for special international projects. Reserves permitted for extraction are substantial and resources are fairly extensive so the stone will be accessible in the long term. Taking such points into account, it is suggested that Bath Stone should be recognised as a Global Heritage Stone Resource.

  10. Does work really cause distress? The contribution of occupational structure and work organization to the experience of psychological distress.

    PubMed

    Marchand, Alain; Demers, Andrée; Durand, Pierre

    2005-07-01

    This research examines the specific contribution of occupation and work organization conditions on psychological distress, based on a representative sample of 9501 workers in 419 occupations in Quebec, Canada. Multilevel regression models show that occupational structure accounts for 0.8% of variation in psychological distress. Among the constraints and resources related to work organization condition, physical and psychological demands, irregular schedules, and workplace harassment emerge as important determinants of psychological distress. The effects of work organization conditions do not vary across occupations. Family situation, support available from social networks outside work, and personal characteristics of individuals are also associated with psychological distress, but these factors do not moderate the effects of work organization conditions. Overall, the findings support the hypothesis that occupation and, to an even greater extent, "pathogenic" work organization conditions contribute independently to the experience of psychological distress. They also support the theoretical model conceptualizing psychological distress as the product of stress caused by constraints and resources brought to bear simultaneously by the agent's personality, structures of daily life, and macrosocial structures. PMID:15847957

  11. The Discovery-Oriented Approach to Organic Chemistry. 7. Rearrangement of "trans"-Stilbene Oxide with Bismuth Trifluoromethanesulfonate and Other Metal Triflates: A Microscale Green Organic Chemistry Laboratory Experiment

    ERIC Educational Resources Information Center

    Christensen, James E.; Huddle, Matthew G.; Rogers, Jamie L.; Yung, Herbie; Mohan, Ram S.

    2008-01-01

    Although green chemistry principles are increasingly stressed in the undergraduate curriculum, there are only a few lab experiments wherein the toxicity of reagents is taken into consideration in the design of the experiment. We report a microscale green organic chemistry laboratory experiment that illustrates the utility of metal triflates,…

  12. A stochastic reorganizational bath model for electronic energy transfer.

    PubMed

    Fujita, Takatoshi; Huh, Joonsuk; Aspuru-Guzik, Alán

    2014-06-28

    Environmentally induced fluctuations of the optical gap play a crucial role in electronic energy transfer dynamics. One of the simplest approaches to incorporate such fluctuations in energy transfer dynamics is the well known Haken-Strobl-Reineker (HSR) model, in which the energy-gap fluctuation is approximated as white noise. Recently, several groups have employed molecular dynamics simulations and excited-state calculations in conjunction to account for excitation energies' thermal fluctuations. On the other hand, since the original work of HSR, many groups have employed stochastic models to simulate the same transfer dynamics. Here, we discuss a rigorous connection between the stochastic and the atomistic bath models. If the phonon bath is treated classically, time evolution of the exciton-phonon system can be described by Ehrenfest dynamics. To establish the relationship between the stochastic and atomistic bath models, we employ a projection operator technique to derive the generalized Langevin equations for the energy-gap fluctuations. The stochastic bath model can be obtained as an approximation of the atomistic Ehrenfest equations via the generalized Langevin approach. Based on this connection, we propose a novel scheme to take account of reorganization effects within the framework of stochastic models. The proposed scheme provides a better description of the population dynamics especially in the regime of strong exciton-phonon coupling. Finally, we discuss the effect of the bath reorganization in the absorption and fluorescence spectra of ideal J-aggregates in terms of the Stokes shifts. We find a simple expression that relates the reorganization contribution to the Stokes shifts - the reorganization shift - to the ideal or non-ideal exciton delocalization in a J-aggregate. The reorganization shift can be described by three parameters: the monomer reorganization energy, the relaxation time of the optical gap, and the exciton delocalization length. This simple relationship allows one to understand the physical origin of the Stokes shifts in molecular aggregates. PMID:24985614

  13. A stochastic reorganizational bath model for electronic energy transfer

    SciTech Connect

    Fujita, Takatoshi, E-mail: tfujita@fas.harvard.edu, E-mail: aspuru@chemistry.harvard.edu; Huh, Joonsuk; Aspuru-Guzik, Alán, E-mail: tfujita@fas.harvard.edu, E-mail: aspuru@chemistry.harvard.edu [Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138 (United States)

    2014-06-28

    Environmentally induced fluctuations of the optical gap play a crucial role in electronic energy transfer dynamics. One of the simplest approaches to incorporate such fluctuations in energy transfer dynamics is the well known Haken-Strobl-Reineker (HSR) model, in which the energy-gap fluctuation is approximated as white noise. Recently, several groups have employed molecular dynamics simulations and excited-state calculations in conjunction to account for excitation energies’ thermal fluctuations. On the other hand, since the original work of HSR, many groups have employed stochastic models to simulate the same transfer dynamics. Here, we discuss a rigorous connection between the stochastic and the atomistic bath models. If the phonon bath is treated classically, time evolution of the exciton-phonon system can be described by Ehrenfest dynamics. To establish the relationship between the stochastic and atomistic bath models, we employ a projection operator technique to derive the generalized Langevin equations for the energy-gap fluctuations. The stochastic bath model can be obtained as an approximation of the atomistic Ehrenfest equations via the generalized Langevin approach. Based on this connection, we propose a novel scheme to take account of reorganization effects within the framework of stochastic models. The proposed scheme provides a better description of the population dynamics especially in the regime of strong exciton-phonon coupling. Finally, we discuss the effect of the bath reorganization in the absorption and fluorescence spectra of ideal J-aggregates in terms of the Stokes shifts. We find a simple expression that relates the reorganization contribution to the Stokes shifts – the reorganization shift – to the ideal or non-ideal exciton delocalization in a J-aggregate. The reorganization shift can be described by three parameters: the monomer reorganization energy, the relaxation time of the optical gap, and the exciton delocalization length. This simple relationship allows one to understand the physical origin of the Stokes shifts in molecular aggregates.

  14. A stochastic reorganizational bath model for electronic energy transfer

    E-print Network

    Takatoshi Fujita; Joonsuk Huh; Alan Aspuru-Guzik

    2014-06-06

    The fluctuations of optical gap induced by the environment play crucial roles in electronic energy transfer dynamics. One of the simplest approaches to incorporate such fluctuations in energy transfer dynamics is the well known Haken-Strobl-Reineker model, in which the energy-gap fluctuation is approximated as a white noise. Recently, several groups have employed molecular dynamics simulations and excited-state calculations in conjunction to take the thermal fluctuation of excitation energies into account. Here, we discuss a rigorous connection between the stochastic and the atomistic bath models. If the phonon bath is treated classically, time evolution of the exciton-phonon system can be described by Ehrenfest dynamics. To establish the relationship between the stochastic and atomistic bath models, we employ a projection operator technique to derive the generalized Langevin equations for the energy-gap fluctuations. The stochastic bath model can be obtained as an approximation of the atomistic Ehrenfest equations via the generalized Langevin approach. Based on the connection, we propose a novel scheme to correct reorganization effects within the framework of stochastic models. The proposed scheme provides a better description of the population dynamics especially in the regime of strong exciton-phonon coupling. Finally, we discuss the effect of the bath reorganization in the absorption and fluorescence spectra of ideal J-aggregates in terms of the Stokes shifts. For this purpose, we introduce a simple relationship that relates the reorganization contribution to the Stokes shifts - the reorganization shift - to three parameters: the monomer reorganization energy, the relaxation time of the optical gap, and the exciton delocalization length. This simple relationship allows one to classify the origin of the Stokes shifts in molecular aggregates.

  15. The Jumping Ring Experiment

    ERIC Educational Resources Information Center

    Baylie, M.; Ford, P. J.; Mathlin, G. P.; Palmer, C.

    2009-01-01

    The jumping ring experiment has become central to liquid nitrogen shows given as part of the outreach and open day activities carried out within the University of Bath. The basic principles of the experiment are described as well as the effect of changing the geometry of the rings and their metallurgical state. In general, aluminium rings are…

  16. Determination of the Absolute Stereochemistry of Secondary Alcohols: An Advanced Organic Chemistry Experiment for Undergraduate Students.

    ERIC Educational Resources Information Center

    Bandaranayake, Wickramasinghe M.

    1980-01-01

    Describes experiments which can be completed in five four-hour laboratory sessions, including two synthesis (alpha-phenylbutyric and alpha-phenylbutyric acid anhydride) and determining the absolute stereochemistry of secondary alcohols using the synthetic products. (JN)

  17. Synthesis of Chemiluminescent Esters: A Combinatorial Synthesis Experiment for Organic Chemistry Students

    ERIC Educational Resources Information Center

    Duarte, Robert; Nielson, Janne T.; Dragojlovic, Veljko

    2004-01-01

    A group of techniques aimed at synthesizing a large number of structurally diverse compounds is called combinatorial synthesis. Synthesis of chemiluminescence esters using parallel combinatorial synthesis and mix-and-split combinatorial synthesis is experimented.

  18. Processing of combined domestic bath and laundry waste waters for reuse as commode flushing water

    NASA Technical Reports Server (NTRS)

    Hypes, W. D.; Batten, C. E.; Wilkins, J. R.

    1975-01-01

    An experimental investigation of processes and system configurations for reclaiming combined bath and laundry waste waters for reuse as commode flush water was conducted. A 90-min recycle flow was effective in removing particulates and in improving other physical characteristics to the extent that the filtered water was subjectively acceptable for reuse. The addition of a charcoal filter resulted in noticeable improvements in color, turbidity, and suds elimination. Heating and chlorination of the waste waters were investigated for reducing total organism counts and eliminating coliform organisms. A temperature of 335.9 K (145 F) for 30 min and chlorine concentrations of 20 mg/l in the collection tank followed by 10 mg/l in the storage tank were determined to be adequate for this purpose. Water volume relationships and energy-use rates for the waste water reuse systems are also discussed.

  19. Hierarchical organization of intelligence

    E-print Network

    Bryson, Joanna J.

    Hierarchical organization of intelligence Ethology and AI perspectives Joanna J. Bryson Department of Computer Science, University of Bath #12;Outline · History: Ethology and AI · Parallel-rooted, Ordered learning · Hierarchies in brains and other evolved intelligence #12;Ethology: Controversy · Mc

  20. Biogeochemistry of two types of permeable reactive barriers, organic carbon and iron-bearing organic carbon for mine drainage treatment: column experiments.

    PubMed

    Guo, Qiang; Blowes, David W

    2009-07-21

    Permeable reactive barriers (PRBs) are an alternative technology to treat mine drainage containing sulfate and heavy metals. Two column experiments were conducted to assess the suitability of an organic carbon (OC) based reactive mixture and an Fe(0)-bearing organic carbon (FeOC) based reactive mixture, under controlled groundwater flow conditions. The organic carbon mixture contains about 30% (volume) organic carbon (composted leaf mulch) and 70% (volume) sand and gravel. The Fe(0)-bearing organic carbon mixture contains 10% (volume) zero-valent iron, 20% (volume) organic carbon, 10% (volume) limestone, and 60% (volume) sand and gravel. Simulated groundwater containing 380 ppm sulfate, 5 ppm As, and 0.5 ppm Sb was passed through the columns at flow rates of 64 (the OC column) and 62 (the FeOC column) ml d(-1), which are equivalent to 0.79 (the OC column) and 0.78 (the FeOC column) pore volumes (PVs) per week or 0.046 m d(-1) for both columns. The OC column showed an initial sulfate reduction rate of 0.4 micromol g (OC)(-1) d(-1) and exhausted its capacity to promote sulfate reduction after 30 PVs, or 9 months of flow. The FeOC column sustained a relatively constant sulfate reduction rate of 0.9 micromol g (OC)(-1) d(-1) for at least 65 PVs (17 months). In the FeOC column, the delta34S values increase with the decreasing sulfate concentration. The delta34S fractionation follows a Rayleigh fractionation model with an enrichment factor of 21.6 per thousand. The performance decline of the OC column was caused by the depletion of substrate or electron donor. The cathodic production of H2 by anaerobic corrosion of Fe probably sustained a higher level of SRB activity in the FeOC column. These results suggest that zero-valent iron can be used to provide an electron donor in sulfate reducing PRBs. A sharp increase in the delta(13)C value of the dissolved inorganic carbon and a decrease in the concentration of HCO3- indicate that hydrogenotrophic methanogenesis is occurring in the first 15 cm of the FeOC column. PMID:19467564

  1. Biogeochemistry of two types of permeable reactive barriers, organic carbon and iron-bearing organic carbon for mine drainage treatment: Column experiments

    NASA Astrophysics Data System (ADS)

    Guo, Qiang; Blowes, David W.

    2009-07-01

    Permeable reactive barriers (PRBs) are an alternative technology to treat mine drainage containing sulfate and heavy metals. Two column experiments were conducted to assess the suitability of an organic carbon (OC) based reactive mixture and an Fe 0-bearing organic carbon (FeOC) based reactive mixture, under controlled groundwater flow conditions. The organic carbon mixture contains about 30% (volume) organic carbon (composted leaf mulch) and 70% (volume) sand and gravel. The Fe 0-bearing organic carbon mixture contains 10% (volume) zero-valent iron, 20% (volume) organic carbon, 10% (volume) limestone, and 60% (volume) sand and gravel. Simulated groundwater containing 380 ppm sulfate, 5 ppm As, and 0.5 ppm Sb was passed through the columns at flow rates of 64 (the OC column) and 62 (the FeOC column) ml d - 1 , which are equivalent to 0.79 (the OC column) and 0.78 (the FeOC column) pore volumes (PVs) per week or 0.046 m d - 1 for both columns. The OC column showed an initial sulfate reduction rate of 0.4 µmol g (OC) - 1 d - 1 and exhausted its capacity to promote sulfate reduction after 30 PVs, or 9 months of flow. The FeOC column sustained a relatively constant sulfate reduction rate of 0.9 µmol g (OC) - 1 d - 1 for at least 65 PVs (17 months). In the FeOC column, the ?34S values increase with the decreasing sulfate concentration. The ?34S fractionation follows a Rayleigh fractionation model with an enrichment factor of 21.6‰. The performance decline of the OC column was caused by the depletion of substrate or electron donor. The cathodic production of H 2 by anaerobic corrosion of Fe probably sustained a higher level of SRB activity in the FeOC column. These results suggest that zero-valent iron can be used to provide an electron donor in sulfate reducing PRBs. A sharp increase in the ?13C value of the dissolved inorganic carbon and a decrease in the concentration of HCO 3- indicate that hydrogenotrophic methanogenesis is occurring in the first 15 cm of the FeOC column.

  2. 78 FR 53734 - Proposed Extension of Approval of Information Collection; Comment Request-Infant Bath Seats

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-30

    ...Information Collection; Comment Request--Infant Bath Seats AGENCY: Consumer Product Safety...information for the safety standard for infant bath seats. The Office of Management...consumer product safety standards for durable infant or toddler products. These...

  3. CQESTR Simulation of Soil Organic Matter Dynamics in Long-term Agricultural Experiments across USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil organic matter (SOM) has important chemical (supplies nutrients, buffers and adsorbs harmful chemical compounds), biological (supports the growth of microorganisms and micro fauna), and physical (improves soil structure and soil tilth, stores water, and reduces surface crusting, water runoff) f...

  4. Knowledge sharing within organizations: linking art, theory, scenarios and professional experience

    NASA Technical Reports Server (NTRS)

    Burton, Y. C.; Bailey, T.

    2000-01-01

    In this presentation, Burton and Bailey, discuss the challenges and opportunities in developing knowledge sharing systems in organizations. Bailey provides a tool using imagery and collage for identifying and utilizing the diverse values and beliefs of individuals and groups. Burton reveals findings from a business research study that examines how social construction influences knowledge sharing among task oriented groups.

  5. Using a Premade Grignard Reagent to Synthesize Tertiary Alcohols in a Convenient Investigative Organic Laboratory Experiment

    ERIC Educational Resources Information Center

    Berg, Michael A. G.; Pointer, Roy D.

    2007-01-01

    A commercially available Grignard reagent (3.0 M solution of phenyl magnesium bromide in ether) was used in a convenient Grignard synthesis in a second-year organic chemistry laboratory without any of the typical failures associated with the Grignard reaction. The reaction setup used oven-dried glassware and no extraordinary measures were taken to…

  6. The Organization of a Teaching Nursing Home: An Eight-Year Experience.

    ERIC Educational Resources Information Center

    Garrell, Marvin

    1983-01-01

    High quality care and teaching in a nursing home require organization of an active medical staff that enhances and does not distract from a physician's commitment to his practice in the office and hospital. The medical residency program at the Jewish Home for the Elderly of Fairfield, Connecticut, is described. (MLW)

  7. Fate of lignin, cutin and suberin in soil organic matter fractions - an incubation experiment

    Microsoft Academic Search

    Carsten W. Mueller; Kevin E. Mueller; Katherine H. Freeman; Kögel-Knabner Ingrid

    2010-01-01

    The turnover of soil organic matter (SOM) is controlled by its chemical composition, its spatial accessibility and the association with the mineral phase. Separation of bulk soils by physical fractionation and subsequent chemical analysis of these fractions should give insights to how compositional differences in SOM drive turnover rates of different size-defined carbon pools. The main objective of this study

  8. Optimization of external coupling and light emission in organic light-emitting devices: modeling and experiment

    E-print Network

    Optimization of external coupling and light emission in organic light-emitting devices: modeling for publication 16 October 2001 The emission of light and external coupling after the appropriate excitons have light can be classified into three modes: externally emitted, substrate waveguided, and indium

  9. Contradictory Aspects of Organized Youth Sport: Challenging and Fostering Sibling Relationships and Participation Experiences

    ERIC Educational Resources Information Center

    Trussell, Dawn E.

    2014-01-01

    This article presents findings from an interpretive study that sought to understand how organized sport at the community level influences sibling relationships and interactions. The meanings of the participants' sport involvement, in relation to their siblings', was also examined using a constructivist approach to grounded theory.…

  10. Simulating Soil Organic Carbon Dynamics in Long-term Agricultural Experiments Using CQESTR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Soil carbon (C) models are useful for examining the complex interactions between climate, crop, and soil management practices and their influences on long-term changes in soil organic carbon (SOC). The CQESTR model was developed to evaluate the effect of agricultural management practices on short- a...

  11. Simulating trends in soil organic carbon in long-term experiments using the century model

    Microsoft Academic Search

    R. H. Kelly; W. J. Parton; G. J. Crocker; P. R. Graced; J. Klír; M. Körschens; P. R. Poulton; D. D. Richter

    1997-01-01

    This paper describes Century Soil Organic Matter (SOM) Model simulations of seven long-term data sets that are the subject of this special issue. We found that Century successfully simulates SOM C across a variety of land use and climate types. Simulations of SOM were most successful in grass and crop systems. This exercise highlights a structural limitation of Century in

  12. Cerebral Organization for Language in Deaf and Hearing Subjects: Biological Constraints and Effects of Experience

    Microsoft Academic Search

    Helen J. Neville; Daphne Bavelier; David Corina; Josef Rauschecker; Avi Karni; Anil Lalwani; Allen Braun; Vince Clark; Peter Jezzard; Robert Turner

    1998-01-01

    Cerebral organization during sentence processing in English and in American Sign Language (ASL) was characterized by employing functional magnetic resonance imaging (fMRI) at 4 T. Effects of deafness, age of language acquisition, and bilingualism were assessed by comparing results from (i) normally hearing, monolingual, native speakers of English, (ii) congenitally, genetically deaf, native signers of ASL who learned English late

  13. South Florida Sun-Sentinel.com All about the 'bath salts' that aren't really for your bath

    E-print Network

    Belogay, Eugene A.

    hallucinogen not to be confused with synthetic marijuana. Both are designer drugs, but fake pot is sold as herbal incense and promises -- but does not always deliver -- a marijuana-like high. It's easy to tell't handle. It can make them stronger." #12;Easy to get Like synthetic marijuana, "bath salts" are sold

  14. Inborn and experience-dependent models of categorical brain organization. A position paper

    PubMed Central

    Gainotti, Guido

    2015-01-01

    The present review aims to summarize the debate in contemporary neuroscience between inborn and experience-dependent models of conceptual representations that goes back to the description of category-specific semantic disorders for biological and artifact categories. Experience-dependent models suggest that categorical disorders are the by-product of the differential weighting of different sources of knowledge in the representation of biological and artifact categories. These models maintain that semantic disorders are not really category-specific, because they do not respect the boundaries between different categories. They also argue that the brain structures which are disrupted in a given type of category-specific semantic disorder should correspond to the areas of convergence of the sensory-motor information which play a major role in the construction of that category. Furthermore, they provide a simple interpretation of gender-related categorical effects and are supported by studies assessing the importance of prior experience in the cortical representation of objects On the other hand, inborn models maintain that category-specific semantic disorders reflect the disruption of innate brain networks, which are shaped by natural selection to allow rapid identification of objects that are very relevant for survival. From the empirical point of view, these models are mainly supported by observations of blind subjects, which suggest that visual experience is not necessary for the emergence of category-specificity in the ventral stream of visual processing. The weight of the data supporting experience-dependent and inborn models is thoroughly discussed, stressing the fact observations made in blind subjects are still the subject of intense debate. It is concluded that at the present state of knowledge it is not possible to choose between experience-dependent and inborn models of conceptual representations. PMID:25667570

  15. 33 CFR 110.133 - Kennebec River in vicinity of Bath, Maine.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Kennebec River in vicinity of Bath, Maine. 110.133 Section 110.133 Navigation... Kennebec River in vicinity of Bath, Maine. (a) The anchorage grounds. Vessels...the north side of Commerce Street, Bath, Maine, to a point on the shore in...

  16. Bath-Related Thunderclap Headache: A Study of 21 Consecutive Patients

    Microsoft Academic Search

    S-J Wang; J-L Fuh; Z-A Wu; S-P Chen; J-F Lirng

    2008-01-01

    We consecutively recruited 21 patients (all women, mean 54 ± 8 years) with bath-related thunderclap headache (BRTH). Thirteen of them were in menopause, two had just ceased hormonal therapy, and one was at 3 months postpartum. Bathing was the initial trigger for thunderclap headaches in nine patients (43%). Many patients (n = 15, 71%) had other non-bath-related attacks. Most patients

  17. Bath Institute for Complex Systems Minimal supporting subtrees for the free energy of polymers

    E-print Network

    Burton, Geoffrey R.

    BICS Bath Institute for Complex Systems Minimal supporting subtrees for the free energy of polymers) http://www.bath.ac.uk/math-sci/BICS #12;Minimal supporting subtrees for the free energy of polymers Bath BA2 7AY United Kingdom Abstract: We consider a model of directed polymers on a regular tree

  18. Black hole evaporation in a heat bath as a nonequilibrium process and its final fate

    Microsoft Academic Search

    Hiromi Saida

    2007-01-01

    We consider a black hole in a heat bath, and the whole system which consists of the black hole and the heat bath is isolated from outside environments. When the black hole evaporates, the Hawking radiation causes an energy flow from the black hole to the heat bath. Therefore, since no energy flow arises in an equilibrium state, the thermodynamic

  19. INVESTIGATION INTO THE REJUVENATION OF SPENT ELECTROLESS NICKEL BATHS BY ELECTRODIALYSIS

    EPA Science Inventory

    Electroless nickel plating generates substantially more waste than other metal-finishing processes due to the inherent limited bath life and the need for regular bath disposal. Electrodialysis can be used to generate electroless nickel baths, but poor membrane permselectivity, l...

  20. DARREN COSKER, BSc (Hons), Ph.D Web: http://www.cs.bath.ac.uk/~dpc

    E-print Network

    Martin, Ralph R.

    VFX & University of Bath · Development of next generation facial technology for movies. · Advanced, University of Bath · Responsible for managing research teams, supervising students (PhD/MSc/BSc), acquiring). 2007 - present Royal Academy of Engineering/EPSRC Fellow, University of Bath · Project title

  1. University of Bath Open Access Publications Full-Text Deposit Mandate -Why do this?

    E-print Network

    McCusker, Guy

    University of Bath Open Access Publications Full-Text Deposit Mandate - Why do this? Why do this? 1, providing safe and legal online storage. The Library also provides help and guidance. University of Bath Open Access Publications Full-Text Deposit Mandate 1. The University of Bath requires researchers

  2. University of Bath -Student Records & Examinations Office -Student numbers -1 Dec 1999 Student Records & Examinations

    E-print Network

    Burton, Geoffrey R.

    University of Bath - Student Records & Examinations Office - Student numbers - 1 Dec 1999 Student studying at, or in association with, the University of Bath in the academic year 1999-2000 at the snapshot or TEMPUS programmes; staff are University of Bath full-time staff who are also registered as part

  3. Text of the PowerPoint presentation for the University of Bath The University

    E-print Network

    Burton, Geoffrey R.

    Text of the PowerPoint presentation for the University of Bath The University The University of Bath is one of the UK's leading universities with a vibrant and innovative academic community. Its small friendly campus overlooks the beautiful UNESCO world heritage city of Bath. The University has

  4. University of Bath -Student Records & Examinations Office -Student numbers -1 Dec 2000 Student Records & Examinations

    E-print Network

    Burton, Geoffrey R.

    University of Bath - Student Records & Examinations Office - Student numbers - 1 Dec 2000 Student with, the University of Bath in the academic year 2000/01 at the snapshot date of 1 December 2000 are University of Bath full-time staff who are also registered as part-time students; the rest are core students

  5. University of Bath Association of Research Libraries / Texas A&M University

    E-print Network

    Rzepa, Henry S.

    University of Bath Association of Research Libraries / Texas A&M University www;University of Bath Association of Research Libraries / Texas A&M University www.libqual.org Contributors or University SCONUL All #12;LibQUAL+® 2007 Survey Results - University of Bath Page 3 of 101 1 Introduction 1

  6. University of Bath Association of Research Libraries / Texas A&M University

    E-print Network

    Rzepa, Henry S.

    University of Bath Association of Research Libraries / Texas A&M University www;University of Bath Association of Research Libraries / Texas A&M University www.libqual.org Contributors - University of Bath Page 1 of 96 1 Introduction 1.1 Acknowledgements This notebook contains information from

  7. University of Bath Association of Research Libraries / Texas A&M University

    E-print Network

    Rzepa, Henry S.

    University of Bath Association of Research Libraries / Texas A&M University www;University of Bath Association of Research Libraries / Texas A&M University www.libqual.org Contributors or University SCONUL All #12;LibQUAL+® 2009 Survey Results - University of Bath Page 3 of 101 1 Introduction 1

  8. University of Bath Association of Research Libraries / Texas A&M University

    E-print Network

    Rzepa, Henry S.

    University of Bath Association of Research Libraries / Texas A&M University www.libqual.org 2011 Survey 8,584 Revised #12;#12;University of Bath Colleen Cook David Green McGill University Association - University of Bath This notebook contains information from the 2011 administration of the LibQUAL+® protocol

  9. University of Bath Association of Research Libraries / Texas A&M University

    E-print Network

    Rzepa, Henry S.

    University of Bath Association of Research Libraries / Texas A&M University www.libqual.org 2013 Survey 10,586 #12;#12;University of Bath Colleen Cook Martha Kyrillidou McGill University Association - University of Bath This notebook contains information from the 2013 administration of the LibQUAL+® protocol

  10. University of Bath -Student Numbers at 1 December 2001 Student Records & Examinations

    E-print Network

    Burton, Geoffrey R.

    University of Bath - Student Numbers at 1 December 2001 Student Records & Examinations Office of students studying at, or in association with, the University of Bath in the academic year 2001 or TEMPUS programmes; staff are University of Bath full-time staff who are also registered as part

  11. Wash and Wean: Bathing Patients Undergoing Weaning Trials During Prolonged Mechanical Ventilation

    PubMed Central

    Happ, Mary Beth; Tate, Judith A.; Swigart, Valerie A.; DiVirgilio-Thomas, Dana; Hoffman, Leslie A.

    2010-01-01

    BACKGROUND Bathing is a fundamental nursing care activity performed for or with the self-assistance of critically ill patients. Few studies address caregiver and/or patient-family perspectives about bathing activity during weaning from prolonged mechanical ventilation. OBJECTIVE To describe practices and beliefs about bathing patients during weaning from prolonged mechanical ventilation (PMV). METHODS Secondary analysis of qualitative data (observational field notes, interviews, and clinical record review) from a larger ethnographic study involving 30 patients weaning from PMV and the clinicians who cared for them using basic qualitative description. RESULTS Bathing, hygiene, and personal care were highly valued and equated with “good” nursing care by families and nurses. Nurses and respiratory therapists reported “working around” bath time and promoted conducting weaning trials before or after bathing. Patients were nevertheless bathed during weaning trials despite clinicians expressed concerns for energy conservation. Clinicians’ recognized individual patient response to bathing during PMV weaning trials. CONCLUSION Bathing is a central care activity for PMV patients and a component of daily work processes in the ICU. Bathing requires assessment of patient condition and activity tolerance and nurse-respiratory therapist negotiation and accommodation with respect to the initiation and/or continuation of PMV weaning trials during bathing. Further study is needed to validate the impact (or lack of impact) of various timing strategies for bathing PMV patients. PMID:20561877

  12. Thermal alteration experiments on organic matter from recent marine sediments in relation to petroleum genesis

    NASA Technical Reports Server (NTRS)

    Ishiwatari, R.; Ishiwatari, M.; Rohrback, B. G.; Kaplan, I. R.

    1977-01-01

    Three fractions of organic matter: lipid (benzene:methanol-extractable), humic acid (alkali-extractable) and kerogen (residue) were extracted from a young marine sediment (Tanner Basin, offshore southern California) and heated for different times (5-116 hr) and temperatures (150-410 C). The volatile (gases) and liquid products, as well as residual material, were then analyzed. On a weight basis, the lipid fraction produced 58% of the total identified n-alkanes, the kerogen fraction 41%, and the humic acid less than 1%. The volatiles produced by heating the lipid and humic acid fractions were largely CO2 and water, whereas those produced from heated kerogen also included methane, hydrogen gas and small amounts of C2-C4 hydrocarbons. A mechanism for hydrocarbon production due to the thermal alteration of organic constituents of marine sediment is discussed.

  13. Forging community partnerships to improve health care: the experience of four Medicaid managed care organizations.

    PubMed

    Silow-Carroll, Sharon; Rodin, Diana

    2013-04-01

    Some managed care organizations (MCOs) serving Medicaid beneficiaries are actively engaging in community partnerships to meet the needs of vulnerable members and nonmembers. We found that the history, leadership, and other internal factors of four such MCOs primarily drive that focus. However, external factors such as state Medicaid policies and competition or collaboration among MCOs also play a role. The specific strat­egies of these MCOs vary but share common goals: (1) improve care coordination, access, and delivery; (2) strengthen the community and safety-net infrastructure; and (3) prevent illness and reduce disparities. The MCOs use data to identify gaps in care, seek community input in designing interventions, and commit resources to engage community organiza­tions. State Medicaid programs can promote such work by establishing goals, priorities, and guidelines; providing data analysis and technical assistance to evaluate local needs and community engagement efforts; and convening stakeholders to collaborate and share best practices. PMID:23634464

  14. Biogeochemistry of particulate organic matter in the oceans: results from sediment trap experiments

    NASA Astrophysics Data System (ADS)

    Wakeham, Stuart G.; Lee, Cindy; Farrington, John W.; Gagosian, Robert B.

    1984-05-01

    Particulate organic matter collected in sediment traps from various oceanic regimes— Sargasso Sea, equatorial North Atlantic, central North Pacific, California Current, and Peru coastal upwelling—have been analyzed for their lipid and amino acid composition and flux. Despite rapid settling of the large particles through the water column and a relatively small depth gradient for total organic carbon flux, there are major changes in the composition and flux of lipids and amino acids associated with the particles. The rapid disappearance of the more labile compounds, such as amino acids and polyunsaturated fatty acids, with increasing depth indicates that the major sources of such compounds are in the upper part of the water column and that they are readily degraded as the particles sink. On the other hand, the intermittent appearance of large amounts of wax ester, along with the changing fatty acid composition of the particles, points to deep-water sources for some of these compounds.

  15. Adsorption of propane, propylene and isobutane on a metal–organic framework: Molecular simulation and experiment

    Microsoft Academic Search

    Nabil Lamia; Miguel Jorge; Miguel A. Granato; Filipe A. Almeida Paz; Hubert Chevreau; Alírio E. Rodrigues

    2009-01-01

    The separation of propane\\/propylene mixtures is the most energy-intensive operation practiced in the petrochemical industry. Adsorptive processes are currently viewed as a promising alternative to cryogenic distillation for the separation of these mixtures. In this paper, we explore the possibility of using a new metal–organic framework material, CuBTC, in adsorptive separation processes, particularly in a simulated moving bed (SMB) context

  16. Gender Mainstreaming in Community-Oriented Wildlife Conservation: Experiences from Nongovernmental Conservation Organizations in India

    Microsoft Academic Search

    Monica V. Ogra

    2012-01-01

    Gender mainstreaming (GM) is the promotion of gender equity and women's empowerment in institutional policy and practice. GM can potentially improve community-oriented conservation outcomes because gender roles often shape values, knowledge, use, and access\\/control of environmental resources. Through a mixed-methods study of 52 nongovernmental organization (NGO)-based, community-oriented wildlife conservation projects in India, this article examines supervisors’ perceptions of the effectiveness

  17. Source apportionment of fine organic aerosol in Mexico City during the MILAGRO Experiment 2006

    NASA Astrophysics Data System (ADS)

    Stone, E. A.; Snyder, D. C.; Sheesley, R. J.; Sullivan, A. P.; Weber, R. J.; Schauer, J. J.

    2007-07-01

    Organic carbon (OC) comprises a large fraction of fine particulate matter (PM2.5) in Mexico City. Daily and select 12-h PM2.5 samples were collected in urban and peripheral sites in Mexico City from 17-30 March 2006. Samples were analyzed for OC and elemental carbon (EC) using thermal-optical filter-based methods. Real-time water-soluble organic carbon (WSOC) was collected at the peripheral site. Organic compounds, particularly molecular markers, were quantified by soxhlet extraction with methanol and dichloromethane, derivitization, and gas chromatography with mass spectrometric detection (GCMS). A chemical mass balance model (CMB) based on molecular marker species was used to determine the relative contribution of major sources to ambient OC. Motor vehicles, including diesel and gasoline, consistently accounted for 47% of OC in the urban area and 31% on the periphery. The daily contribution of biomass burning to OC was highly variable, and ranged from 5-30% at the urban site and 11-50% at the peripheral site. The remaining OC unapportioned to primary sources showed a strong correlation with WSOC and was considered to be secondary in nature. Comparison of temporally resolved OC showed that contributions from primary aerosol sources during daylight hours were not significantly different from nighttime. This study provides quantitative understanding of the important sources of OC during the MILAGRO 2006 field campaign.

  18. Source apportionment of fine organic aerosol in Mexico City during the MILAGRO experiment 2006

    NASA Astrophysics Data System (ADS)

    Stone, E. A.; Snyder, D. C.; Sheesley, R. J.; Sullivan, A. P.; Weber, R. J.; Schauer, J. J.

    2008-03-01

    Organic carbon (OC) comprises a large fraction of fine particulate matter (PM2.5) in Mexico City. Daily and select 12-h PM2.5 samples were collected in urban and peripheral sites in Mexico City from 17-30 March 2006. Samples were analyzed for OC and elemental carbon (EC) using thermal-optical filter-based methods. Real-time water-soluble organic carbon (WSOC) was collected at the peripheral site. Organic compounds, particularly molecular markers, were quantified by soxhlet extraction with methanol and dichloromethane, derivitization, and gas chromatography with mass spectrometric detection (GCMS). A chemical mass balance model (CMB) based on molecular marker species was used to determine the relative contribution of major sources to ambient OC. Motor vehicles, including diesel and gasoline, consistently accounted for 49% of OC in the urban area and 32% on the periphery. The daily contribution of biomass burning to OC was highly variable, and ranged from 5-26% at the urban site and 7-39% at the peripheral site. The remaining OC unapportioned to primary sources showed a strong correlation with WSOC and was considered to be secondary in nature. Comparison of temporally resolved OC showed that contributions from primary aerosol sources during daylight hours were not significantly different from nighttime. This study provides quantitative understanding of the important sources of OC during the MILAGRO 2006 field campaign.

  19. Immediate Dissemination of Student Discoveries to a Model Organism Database Enhances Classroom-Based Research Experiences

    ERIC Educational Resources Information Center

    Wiley, Emily A.; Stover, Nicholas A.

    2014-01-01

    Use of inquiry-based research modules in the classroom has soared over recent years, largely in response to national calls for teaching that provides experience with scientific processes and methodologies. To increase the visibility of in-class studies among interested researchers and to strengthen their impact on student learning, we have…

  20. Polymeric conducting anode for small organic transporting molecules in dark injection experiments

    E-print Network

    So, Shu K.

    2006 Poly 3,4-ethylenedioxythiophene doped with polystrenesulphonic acid PEDOT:PSS is used as a hole experiments, PEDOT:PSS forms an Ohmic contact with MTDATA and a quasi-Ohmic contact with NPB despite from PEDOT:PSS deviates substantially from Ohmic injection, leading to a lower than expected DI

  1. Class Matters: The Experiences of Female College Students in a Greek-Letter Organization

    ERIC Educational Resources Information Center

    Ryan, Helen-Grace

    2009-01-01

    This qualitative study documents the experiences of 15 women from different social class backgrounds who are members of a women's fraternity/sorority at a large, public, institution located in an urban area in the Mid-West. The purpose of the study was to better understand the relationship between social class and the nature and impact of the…

  2. Evaluating Mechanisms of Dihydroxylation by Thin-Layer Chromatography: A Microscale Experiment for Organic Chemistry

    ERIC Educational Resources Information Center

    Burlingham, Benjamin T.; Rettig, Joseph C.

    2008-01-01

    A microscale experiment is presented in which cyclohexene is dihydroxylated under three sets of conditions: epoxidation-hydrolysis, permanganate oxidation, and the Woodward dihydroxylation. The products of the reactions are determined by the use of thin-layer chromatography. Teams of students are presented with proposed mechanisms for each…

  3. Are you experienced? Prior experience and the survival of new organizations

    Microsoft Academic Search

    Michael S. Dahl; Toke Reichstein

    2005-01-01

    This paper investigates the relationship between the level of experience of managers and founders, and the likelihood of survival of their new firms. We take advantage of a comprehensive dataset covering the entire Danish labor market from 1980-2000. This is used to trace the activities of top ranked members of start-ups prior to their founding, and follow the fate of

  4. Experiments on ??34S mixing between organic and inorganic sulfur species during thermal maturation

    USGS Publications Warehouse

    Amrani, A.; Said-Ahamed, W.; Lewan, M.D.; Aizenshtat, Z.

    2006-01-01

    Reduced sulfur species were studied to constrain isotopic exchange-mixing with synthetic polysulfide cross-linked macromolecules (PCLM), model sulfur containing molecules and natural sulfur-rich kerogen, asphalt and oil of the Dead Sea area. PCLM represents protokerogens that are rich in sulfur and thermally unstable. Mixing rates of PCLM with HS-(aq) (added as (NH4)2S(aq)) at low to moderate temperatures (50-200 ??C) are rapid. Elemental sulfur and H2S(gas) fully mix isotopes with PCLM during pyrolysis conditions at 200 ??C. During these reactions significant structural changes of the PCLM occur to form polysulfide dimers, thiolanes and thiophenes. As pyrolysis temperatures or reaction times increase, the PCLM thermal products are transformed to more aromatic sulfur compounds. Isotopic mixing rates increase with increasing pyrolysis temperature and time. Polysulfide bonds (S-S) in the PCLM are responsible for most of these structural and isotopic changes because of their low stability. Conversely, sulfur isotope mixing does not occur between dibenzothiophene (aromatic S) or hexadecanthiol (C-SH) and HS-(aq) at 200 ??C after 48 h. This shows that rates of sulfur isotope mixing are strongly dependent on the functionality of the sulfur in the organic matter. The order of isotopic mixing rates for organic matter is kerogen > asphalt > oil, which is inverse to their sulfur thermal stability. Asphalt and oil with more refractory sulfur show significantly lower isotopes mixing rates than the kerogen with more labile sulfur. Based on the findings of the present study we suggest that sulfur isotopes mixing can occur from early diagenesis into catagenesis and result in isotopic homogenization of the inorganic and organic reduced sulfur pools. ?? 2006 Elsevier Inc. All rights reserved.

  5. Robotic-assisted sacrocolpopexy\\/sacrocervicopexy repair of pelvic organ prolapse: initial experience

    Microsoft Academic Search

    Ahmet GocmenFatih; Fatih ?anl?kan; Mustafa Gazi Uçar

    Purpose  To present the short-term surgical outcomes of robotic-assisted sacrocolpopexy and sacrocervicopexy.\\u000a \\u000a \\u000a \\u000a Methods  Between January 2009 and September 2010, 12 patients underwent robotic-assisted pelvic organ prolapse repair including six\\u000a sacrocolpopexy and six sacrocervicopexy. Patients’ demographics, surgical procedures, operative and postoperative complications,\\u000a hospital stay, conversion to laparotomy, time data including all operative times and estimated blood loss (EBL) were recorded.\\u000a \\u000a \\u000a \\u000a \\u000a Results  All surgeries were

  6. Oregon's Experiment in Health Care Delivery and Payment Reform: Coordinated Care Organizations Replacing Managed Care.

    PubMed

    Howard, Steven W; Bernell, Stephanie L; Yoon, Jangho; Luck, Jeff; Ranit, Claire M

    2015-02-01

    To control Medicaid costs, improve quality, and drive community engagement, the Oregon Health Authority introduced a new system of coordinated care organizations (CCOs). While CCOs resemble traditional Medicaid managed care, they have differences that have been deliberately designed to improve care coordination, increase accountability, and incorporate greater community governance. Reforms include global budgets integrating medical, behavioral, and oral health care and public health functions; risk-adjusted payments rewarding outcomes and evidence-based practice; increased transparency; and greater community engagement. The CCO model faces several implementation challenges. If successful, it will provide improved health care delivery, better health outcomes, and overall savings. PMID:25480844

  7. Optimization of chemical bath deposited cadmium sulfide thin films

    SciTech Connect

    Oladeji, I.O.; Chow, L. [Univ. of Central Florida, Orlando, FL (United States). Dept. of Physics

    1997-07-01

    Cadmium sulfide (CdS) is known to be an excellent heterojunction partner of p-type cadmium telluride (CdTe) or p-type copper indium diselenide (CuInSe{sub 2}) due essentially to its high electron affinity. It is widely used as a window material in high efficiency thin-film solar cells based on CdTe or CuInSe{sub 2} owing to its transparency and photoconductivity among other properties. The authors report the optimization of CdS thin film grown by chemical bath deposition where homogeneous reactions are minimized. The optimum parameters have enabled them to maximize the thickness of the deposited film in a single dip and to grow thicker films by periodically replenishing the concentration of reactants while the substrate remains continuously dipped in the reaction bath. Characterization results reveal the deposited CdS films exhibit improved optical and electrical properties.

  8. Nonequilibrium dynamics of scalar fields in a thermal bath

    SciTech Connect

    Anisimov, A.; Buchmueller, W.; Drewes, M. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany); Mendizabal, S. [Deutsches Elektronen-Synchrotron DESY, Hamburg (Germany)], E-mail: sebastian.mendizabal@desy.de

    2009-06-15

    We study the approach to equilibrium for a scalar field which is coupled to a large thermal bath. Our analysis of the initial value problem is based on Kadanoff-Baym equations which are shown to be equivalent to a stochastic Langevin equation. The interaction with the thermal bath generates a temperature-dependent spectral density, either through decay and inverse decay processes or via Landau damping. In equilibrium, energy density and pressure are determined by the Bose-Einstein distribution function evaluated at a complex quasi-particle pole. The time evolution of the statistical propagator is compared with solutions of the Boltzmann equations for particles as well as quasi-particles. The dependence on initial conditions and the range of validity of the Boltzmann approximation are determined.

  9. Measurement and Analysis of Bath-Side Interfacial Concentration Gradients during Membrane Quenching by Phase Inversion.

    NASA Astrophysics Data System (ADS)

    Gaides, Gary Edward

    A technique based on Fourier transform optical theory has been developed which allows for transient measurements of bath-side interfacial refractive index gradients during the quench step of membrane formation by phase inversion. From examination of individual Fourier components in a diffraction pattern associated with this one-dimensional mass transport process one is able to overcome the temporal and spatial resolution limitations imposed by many of the more traditional optical techniques. A first order expression relating the local refractive index gradient in the quench cell as a function of its measured spatial offset in the Fourier plane was derived for the purpose of determining the interfacial gradient which may be readily converted to individual species (solvent/nonsolvent) concentration gradients. Real-time interfacial gradients were able to be measured anywhere from 2 to 5 seconds after initiation of the quench using this technique. The r.m.s. errors associated with the reported interfacial species concentration gradient values were determined to range between 3% and 7% of the reported values for quench times less than 60 seconds. However, the reproducability of the experiment was shown to be well within these error limits. The bath-side interfacial refractive index gradient was measured as a function of time for both delayed (cellulose acetate in N,N-dimethylformamide with added nonsolvent ethanol) and instantaneous (cellulose acetate or polysulfone in N,N-dimethylformamide with added nonsolvent water) phase separation conditions with allowed variability in the following processing conditions: initial cast film thickness, initial solvent composition in the coagulation bath, initial nonsolvent composition in the casting solution, and initial polymer concentration in the casting solution. The directionality of the change associated with experimentally observed phenomena (bath-side interfacial solvent gradient and the time at which phase separation occurs in the film as determined by light transmission) for both rapid and delayed precipitating systems with appropriate changes in a given processing variable was consistent with qualitative mass transfer suggestions and existing model predictions for all conditions examined in this study. In addition, the experimental gradient data for all rapid precipitation cases were universally quantified through a non-dimensionalization procedure using a 2-parameter phenomenological model.

  10. Supervised Self-Organizing Classification of Superresolution ISAR Images: An Anechoic Chamber Experiment

    Microsoft Academic Search

    Emanuel Radoi; Andr ´ e Quinquis; Felix Totir

    2006-01-01

    The problem of the automatic classification of superresolution ISAR images is addressed in the paper. We describe an ane- choic chamber experiment involving ten-scale-reduced aircraft models. The radar images of these targets are reconstructed using MUSIC-2D (multiple signal classification) method coupled with two additional processing steps: phase unwrapping and symme- try enhancement. A feature vector is then proposed including Fourier

  11. Healthcare reform and the workplace experience of nurses: Implications for patient care and union organizing

    Microsoft Academic Search

    Paul F. Clark; Darlene A. Clark; David V. Day; Dennis G. Shea

    2001-01-01

    The introduction of market-based reforms over the past twenty-five years has fundamentally changed the way healthcare is delivered in the United States. This paper reports the results of a survey of the workplace experiences and attitudes of hospital-based registered nurses under healthcare reform. The authors find that nurses who had experienced reform-related job restructuring held substantially more negative views of

  12. Are You Experienced? Prior Experience and the Survival of New Organizations

    Microsoft Academic Search

    Michael S. Dahl; Toke Reichstein

    2007-01-01

    This paper investigates the relationship between the level of pre?entry experience of managers and founders, and the survival of their new firms. Using a comprehensive dataset covering the entire Danish labor market from 1980 to 2000, we are able to trace prior activities of all employees working in all Danish start?ups with at least one employee. We examine whether spin?offs

  13. A Simple Organic Microscale Experiment Illustrating the Equilibrium Aspect of the Aldol Condensation

    NASA Astrophysics Data System (ADS)

    Harrison, Ernest A., Jr.

    1998-05-01

    A simple microscale experiment has been developed that illustrates the equilibrium aspect of the aldol condensation by using two versions of the standard preparation of tetraphenylcyclopentadienone (5) from benzil (1) and 1,3-diphenyl-2-propanone (2). In version (high base concentration) a mixture of 5 and the diastereomeric 4-hydroxy-2,3,4,5-tetraphenyl-2-cyclopenten-1-ones 3 and 4 are produced, while in the other (low base concentration) a mixture of 1, 2, 3, and 4 results. The experiment is typically carried out in conjunction with the previously reported preparation/dehydration of 3, thus the students provide themselves with authentic samples of 3 and 5. Using these, plus authentic samples of 1 and 2 which are made available, students are able to identify all of the components in the equilibrium mixtures, except 4, by TLC analysis. In the case of 4, students are expected to propose a reasonable structure for this compound based on the observed chemistry and the spectroscopic evidence which is provided (i.e., NMR, IR and mass spectra). The experiment lends itself nicely to either the traditional or problem-solving approach, and it also opens up opportunities for collaborative learning.

  14. Membrane-Associated Quinoprotein Formaldehyde Dehydrogenase from Methylococcus capsulatus Bath

    Microsoft Academic Search

    JAMES A. ZAHN; DAVID J. BERGMANN; JEFFERY M. BOYD; RYAN C. KUNZ; ALAN A. DISPIRITO

    2001-01-01

    A membrane-associated, dye-linked formaldehyde dehydrogenase (DL-FalDH) was isolated from the obli- gate methylotroph Methylococcus capsulatus Bath. The enzyme was the major formaldehyde-oxidizing enzyme in cells cultured in high (above 1 mol of Cu per mg of cell protein) copper medium and expressing the membrane-associated methane monooxygenase. Soluble NAD(P)-linked formaldehyde oxidation was the major activity in cells cultured in low-copper medium

  15. Modified Bloch equations in the presence of a nonstationary bath

    NASA Astrophysics Data System (ADS)

    Chaudhuri, J. R.; Banik, S. K.; Deb, B.; Ray, D. S.

    1999-06-01

    Based on the system-reservoir description we propose a simple solvable microscopic model for a nonequilibrium bath. This captures the essential features of a nonstationary quantum Markov process. We establish an appropriate generalization of the fluctuation-dissipation relation pertaining to this process and explore the essential modifications of the Bloch equations to reveal the nonexponential decay of the Bloch vector components and transient spectral broadening in resonance fluorescence. We discuss a simple experimental scheme to verify the theoretical results.

  16. Modified Bloch equations in presence of a nonstationary bath

    E-print Network

    Jyotipratim Ray Chaudhuri; Suman Kumar Banik; Bimalendu Deb; Deb Shankar Ray

    1999-02-11

    Based on the system-reservoir description we propose a simple solvable microscopic model for a nonequilibrium bath. This captures the essential features of a nonstationary quantum Markov process. We establish an appropriate generalization of the fluctuation-dissipation relation pertaining to this process and explore the essential modifications of the Bloch equations to reveal the nonexponential decay of the Bloch vector components and transient spectral broadening in resonance fluorescence. We discuss a simple experimental scheme to verify the theoretical results.

  17. Hydrogen impurities in chemical bath deposited CdS

    Microsoft Academic Search

    M. Weber; J. Krauser; A. Weidinger; J. Bruns; C. H. Fischer; W. Bohne; J. Roehrich; R. Scheer

    1999-01-01

    Chemical bath deposition is a well-established process for the fabrication of thin CdS films for electro-optic devices. The authors investigate the various impurities in this material with emphasis on hydrogen-related compounds. Nuclear reaction analysis provides hydrogen depth profiles of chemically deposited CdS with mean concentrations up to 12 atom % hydrogen. Using photoelectron spectroscopy only a part of this amount

  18. Directional CdS nanowires fabricated by chemical bath deposition

    Microsoft Academic Search

    Hui Zhang; Xiangyang Ma; Jin Xu; Junjie Niu; Jian Sha; Deren Yang

    2002-01-01

    Directional CdS nanowires have been fabricated by using chemical bath deposition (CBD) and porous anodic aluminum oxide (AAO) template. X-ray diffraction and selected area electron diffraction show that the nanowires are hexagonal polycrystalline in nature. Transmission electron microscopy (TEM) reveals that the diameters of nanowires are about 60nm. Furthermore, the high-resolution TEM illustrates the lattice images of {002}, {101} and

  19. Novel approach to the chemical bath deposition of chalcogenide semiconductors

    Microsoft Academic Search

    D. S. Boyle; A. Bayer; M. R. Heinrich; O. Robbe; P. O'Brien

    2000-01-01

    Chemical bath deposition (CBD) generates has been successfully employed for the fabrication of II–VI semiconductor thin films. Thin film polycrystalline solar cells, such as the BP Solar ‘Apollo’ CdS:CdTe heterojunction device, offer the potential for low cost solar energy conversion. The large scale exploitation of these devices is partly dependent on a reduction of the potential environmental impact of the

  20. Synthesis of CdS nanotubes by chemical bath deposition

    Microsoft Academic Search

    Hui Zhang; Xiangyang Ma; Jin Xu; Deren Yang

    2004-01-01

    CdS nanotubes have been prepared by means of chemical bath deposition (CBD) and nanochannel alumina (NCA) template. X-ray diffraction (XRD) and selected area electron diffraction (SAED) indicate that the nanotubes are of cubic structure. Transmission electron microscopy (TEM) shows the diameters of nanotubes are around 50nm. Furthermore, high-resolution TEM (HRTEM) reveals a clear lattice image of {111} planes in the

  1. Large area Cds thin film grown by chemical bath deposition

    Microsoft Academic Search

    Guogen Liu; Zimeng Cheng; Robert B Barat; Jingong Pan; George E Georgiou; Ken K. Chin

    2011-01-01

    Cadmium Sulfide (CdS) thin films are often deposited on glass substrates coated with TCO layers by the close-spaced sublimation (CSS) or sputter techniques in industrial because in-line production integration. It is seldom reported that CdS is deposited by the chemical bath deposition (CBD) batch process. The bottleneck of CBD for commercial application is its low production rate and waste water

  2. Electrowinning of cerium group metals from fused chloride bath

    Microsoft Academic Search

    Sohan Singh; A L Pappachan

    1980-01-01

    Cerium group metals, namely, misch metal, lanthanum and cerium have been electrowon from their vacuum-dehydrated chlorides\\u000a in fused sodium chloride-potassium chloride and lithium chloride-potassium chloride solvent. Temperature, cathode current\\u000a density and composition of bath were optimised for high current efficiency and metal yield. In the case of lanthanum, current\\u000a efficiency of 88% was achieved. The metals were free from inclusions

  3. Long-Term Experience With World Health Organization Grade III (Malignant) Meningiomas at a Single Institution

    SciTech Connect

    Rosenberg, Lewis A. [Department of Radiation Oncology, Cleveland Clinic Foundation, Cleveland, OH (United States); Case Western Reserve University School of Medicine, Cleveland, OH (United States); Prayson, Richard A. [Department of Pathology, Cleveland Clinic Foundation, Cleveland, OH (United States); Lee, Joung [Department of Neurosurgery, Cleveland Clinic Foundation, Cleveland, OH (United States); Reddy, Chandana; Chao, Samuel T. [Department of Radiation Oncology, Cleveland Clinic Foundation, Cleveland, OH (United States); Barnett, Gene H.; Vogelbaum, Michael A. [Department of Neurosurgery, Cleveland Clinic Foundation, Cleveland, OH (United States); Suh, John H. [Department of Radiation Oncology, Cleveland Clinic Foundation, Cleveland, OH (United States)], E-mail: suhj@ccf.org

    2009-06-01

    Purpose: To evaluate the outcomes for patients with Grade III meningiomas as defined by the 2007 World Health Organization standards. Methods and Materials: The slides from patients who had been treated at the Cleveland Clinic for malignant meningiomas were reviewed by a single neuropathologist. The data from 13 patients treated between 1984 and 2006 satisfied the World Health Organization 2007 definition of Grade III meningioma. A total of 24 surgeries were performed, including 13 primary, 7 salvage, and 4 second salvage. Also, 14 courses of radiotherapy (RT) were administered, including fractionated RT in 3 patients after primary surgery, fractionated RT in 4 patients after salvage surgery, salvage stereotactic radiosurgery to six separate areas in 3 patients, and salvage intensity-modulated RT in 1 patient. Results: From the primary surgery, the median survival was 3.4 years, the 5-year survival rate was 47.2%, and the 8-year survival rate was 12.2%. The median time to recurrence was 9.6 months. A trend was seen toward longer survival for patients who had received adjuvant RT after initial surgery compared with those treated with surgery alone. Two patients developed radiation necrosis, and three had surgical complications. Conclusion: This is one of the few studies reporting the outcomes for malignant meningioma patients according to recent definitions. Our results are consistent with existing reports of the overall poor outcomes for atypical and malignant meningioma patients. From the available data, surgical resection followed by RT and salvage therapy can lead to extended survival.

  4. Water accommodation on ice and organic surfaces: insights from environmental molecular beam experiments.

    PubMed

    Kong, Xiangrui; Thomson, Erik S; Papagiannakopoulos, Panos; Johansson, Sofia M; Pettersson, Jan B C

    2014-11-26

    Water uptake on aerosol and cloud particles in the atmosphere modifies their chemistry and microphysics with important implications for climate on Earth. Here, we apply an environmental molecular beam (EMB) method to characterize water accommodation on ice and organic surfaces. The adsorption of surface-active compounds including short-chain alcohols, nitric acid, and acetic acid significantly affects accommodation of D2O on ice. n-Hexanol and n-butanol adlayers reduce water uptake by facilitating rapid desorption and function as inefficient barriers for accommodation as well as desorption of water, while the effect of adsorbed methanol is small. Water accommodation is close to unity on nitric-acid- and acetic-acid-covered ice, and accommodation is significantly more efficient than that on the bare ice surface. Water uptake is inefficient on solid alcohols and acetic acid but strongly enhanced on liquid phases including a quasi-liquid layer on solid n-butanol. The EMB method provides unique information on accommodation and rapid kinetics on volatile surfaces, and these studies suggest that adsorbed organic and acidic compounds need to be taken into account when describing water at environmental interfaces. PMID:25079605

  5. Hospitals and Health Maintenance Organizations: An Analysis of the Minneapolis-St. Paul Experience

    PubMed Central

    Morrisey, Michael A.; Gibson, Geoffrey; Ashby, Cynthia S.

    1983-01-01

    Minneapolis-St. Paul is recognized as a prime example of health care competition. Policymakers and others have been asked to look to the Twin Cities as a model upon which to base new competitive initiatives in the health care sector. Yet little is known about the impact of Health Maintenance Organizations (HMOs) on other health care providers. This study examines the effects of the area's seven health maintenance organizations on the local hospital community. Three questions are addressed. First, is the situation in the Twin Cities unique? A comparison of case study findings and the available literature together with hospital data from similarly HMO-penetrated markets suggests that the Twin Cities' hospital market is indeed different. Second, what is the nature of hospital-HMO interaction? The flexibility of contracting apparently allows hospitals to affiliate successfully with an HMO under a variety of service and reimbursement agreements. Third, what effect has HMO activity had on community-wide utilization? While HMO enrollees clearly use fewer hospital days and the trend in the community is toward fewer days, attributing the change to HMOs is difficult. A large portion of the differences between HMO and community-wide utilization levels is attributable to differences in population. PMID:10309856

  6. Unusual swelling of a polymer in a bacterial bath

    E-print Network

    Andreas Kaiser; Hartmut Löwen

    2014-06-11

    The equilibrium structure and dynamics of a single polymer chain in a thermal solvent is by now well-understood in terms of scaling laws. Here we consider a polymer in a bacterial bath, i.e. in a solvent consisting of active particles which bring in nonequilibrium fluctuations. Using computer simulations of a self-avoiding polymer chain in two dimensions which is exposed to a dilute bath of active particles, we show that the Flory-scaling exponent is unaffected by the bath activity provided the chain is very long. Conversely, for shorter chains, there is a nontrivial coupling between the bacteria intruding into the chain which may stiffen and expand the chain in a nonuniversal way. As a function of the molecular weight, the swelling first scales faster than described by the Flory exponent, then an unusual plateau-like behaviour is reached and finally a crossover to the universal Flory behaviour is observed. As a function of bacterial activity, the chain end-to-end distance exhibits a pronounced non-monotonicity. Moreover, the mean-square displacement of the center of mass of the chain shows a ballistic behaviour at intermediate times as induced by the active solvent. Our predictions are verifiable in two-dimensional bacterial suspensions and for colloidal model chains exposed to artificial colloidal microswimmers.

  7. Excited state and charge dynamics of hybrid organic/inorganic heterojunctions. II. Experiment

    NASA Astrophysics Data System (ADS)

    Panda, Anurag; Renshaw, C. Kyle; Oskooi, Ardavan; Lee, Kyusang; Forrest, Stephen R.

    2014-07-01

    In our companion paper (Paper I) [C. K. Renshaw and S. R. Forrest, Phys. Rev. B 90, 045302 (2014), 10.1103/PhysRevB.90.045302], we developed a model for charge transport and photogeneration at hybrid organic/inorganic semiconductor heterojunctions (OI-HJs). Here we apply the model to two planar bilayer hybrid photovoltaic devices: the first using the wide-band gap n-TiO2 in combination with the hole transporting tetraphenyl-dibenzoperiflanthene (DBP), and the second based on the moderate-band gap n-InP and the hole transporting pentacene (PEN). We measure the external quantum efficiency (EQE) and current density vs voltage (J-V) characteristics of both devices as functions of temperature. The EQE spectra for both TiO2/DBP and InP/PEN provide convincing evidence that Frenkel states generated in the organic form hybrid charge transfer excitons (HCTEs) at the OI-HJ that are subsequently dissociated into free charges, and then collected at the opposing electrodes. The dissociation efficiency is found to be strongly influenced by the presence of surface states, particularly in the InP/PEN device. We further develop the J-V model from Paper I to include an analytical expression for space-charge effects in the organic at high currents. Model fits to the J-V data suggest that the temperature-dependent hole mobilities in both DBP and PEN result in increasing space-charge effects at low temperatures. Furthermore, we find that the J-V characteristics of the TiO2/DBP device both in the dark and under illumination are governed by interface recombination. In contrast, the dark current in the InP/PEN device is governed by injection over the OI-HJ barrier, whereas the photocurrent is dominated by interface recombination. This work elucidates the role of the HCTE state in photogeneration, and the applicability of our model to a range of important optoelectronic devices.

  8. Assembly of live micro-organisms on microstructured PDMS stamps by convective/capillary deposition for AFM bio-experiments

    NASA Astrophysics Data System (ADS)

    Dague, E.; Jauvert, E.; Laplatine, L.; Viallet, B.; Thibault, C.; Ressier, L.

    2011-09-01

    Immobilization of live micro-organisms on solid substrates is an important prerequisite for atomic force microscopy (AFM) bio-experiments. The method employed must immobilize the cells firmly enough to enable them to withstand the lateral friction forces exerted by the tip during scanning but without denaturing the cell interface. In this work, a generic method for the assembly of living cells on specific areas of substrates is proposed. It consists in assembling the living cells within the patterns of microstructured, functionalized poly-dimethylsiloxane (PDMS) stamps using convective/capillary deposition. This versatile approach is validated by applying it to two systems of foremost importance in biotechnology and medicine: Saccharomyces cerevisiae yeasts and Aspergillus fumigatus fungal spores. We show that this method allows multiplexing AFM nanomechanical measurements by force spectroscopy on S. cerevisiae yeasts and high-resolution AFM imaging of germinated Aspergillus conidia in buffer medium. These two examples clearly demonstrate the immense potential of micro-organism assembly on functionalized, microstructured PDMS stamps by convective/capillary deposition for performing rigorous AFM bio-experiments on living cells.

  9. Assembly of live micro-organisms on microstructured PDMS stamps by convective/capillary deposition for AFM bio-experiments.

    PubMed

    Dague, E; Jauvert, E; Laplatine, L; Viallet, B; Thibault, C; Ressier, L

    2011-09-30

    Immobilization of live micro-organisms on solid substrates is an important prerequisite for atomic force microscopy (AFM) bio-experiments. The method employed must immobilize the cells firmly enough to enable them to withstand the lateral friction forces exerted by the tip during scanning but without denaturing the cell interface. In this work, a generic method for the assembly of living cells on specific areas of substrates is proposed. It consists in assembling the living cells within the patterns of microstructured, functionalized poly-dimethylsiloxane (PDMS) stamps using convective/capillary deposition. This versatile approach is validated by applying it to two systems of foremost importance in biotechnology and medicine: Saccharomyces cerevisiae yeasts and Aspergillus fumigatus fungal spores. We show that this method allows multiplexing AFM nanomechanical measurements by force spectroscopy on S. cerevisiae yeasts and high-resolution AFM imaging of germinated Aspergillus conidia in buffer medium. These two examples clearly demonstrate the immense potential of micro-organism assembly on functionalized, microstructured PDMS stamps by convective/capillary deposition for performing rigorous AFM bio-experiments on living cells. PMID:21891839

  10. Controlling the quantum dynamics of a mesoscopic spin bath in diamond

    PubMed Central

    de Lange, Gijs; van der Sar, Toeno; Blok, Machiel; Wang, Zhi-Hui; Dobrovitski, Viatcheslav; Hanson, Ronald

    2012-01-01

    Understanding and mitigating decoherence is a key challenge for quantum science and technology. The main source of decoherence for solid-state spin systems is the uncontrolled spin bath environment. Here, we demonstrate quantum control of a mesoscopic spin bath in diamond at room temperature that is composed of electron spins of substitutional nitrogen impurities. The resulting spin bath dynamics are probed using a single nitrogen-vacancy (NV) centre electron spin as a magnetic field sensor. We exploit the spin bath control to dynamically suppress dephasing of the NV spin by the spin bath. Furthermore, by combining spin bath control with dynamical decoupling, we directly measure the coherence and temporal correlations of different groups of bath spins. These results uncover a new arena for fundamental studies on decoherence and enable novel avenues for spin-based magnetometry and quantum information processing. PMID:22536480

  11. Linear-algebraic bath transformation for simulating complex open quantum systems

    E-print Network

    Huh, Joonsuk; Fujita, Takatoshi; Yung, Man-Hong; Aspuru-Guzik, Alán

    2014-01-01

    In studying open quantum systems, the environment is often approximated as a collection of non-interacting harmonic oscillators, a configuration also known as the star-bath model. It is also well known that the star-bath can be transformed into a nearest-neighbor interacting chain of oscillators. The chain-bath model has been widely used in renormalization group approaches. The transformation can be obtained by recursion relations or orthogonal polynomials. Based on a simple linear algebraic approach, we propose a bath partition strategy to reduce the system-bath coupling strength. As a result, the non-interacting star-bath is transformed into a set of weakly-coupled multiple parallel chains. The transformed bath model allows complex problems to be practically implemented on quantum simulators, and it can also be employed in various numerical simulations of open quantum dynamics.

  12. Linear-algebraic bath transformation for simulating complex open quantum systems

    NASA Astrophysics Data System (ADS)

    Huh, Joonsuk; Mostame, Sarah; Fujita, Takatoshi; Yung, Man-Hong; Aspuru-Guzik, Alán

    2014-12-01

    In studying open quantum systems, the environment is often approximated as a collection of non-interacting harmonic oscillators, a configuration also known as the star-bath model. It is also well known that the star-bath can be transformed into a nearest-neighbor interacting chain of oscillators. The chain-bath model has been widely used in renormalization group approaches. The transformation can be obtained by recursion relations or orthogonal polynomials. Based on a simple linear algebraic approach, we propose a bath partition strategy to reduce the system-bath coupling strength. As a result, the non-interacting star-bath is transformed into a set of weakly coupled multiple parallel chains. The transformed bath model allows complex problems to be practically implemented on quantum simulators, and it can also be employed in various numerical simulations of open quantum dynamics.

  13. Jasperse Organic II NMR Problems Sat Feb 4 18:00:16 2012: Experiment started

    E-print Network

    Jasperse, Craig P.

    .52.02.53.03.54.0 Plotname: Ethyl_acetate_PROTON_01_plot02 #12; 5 5. C5H10O2 C5H1602' #12; 6 6. C8H10 ppm1.41.61.82.02.22.42.62.8 Sat Feb 4 15:49:21 2012: Experiment started 49.51 19.93 30.56 ppm234567 Plotname: Ethyl.01.52.02.53.03.5 Plotname: Methyl_Butyrate_PROTON_01_plot02 #12; 17 17.C6H12O ppm1.51.61.7 Sat Feb 4 16:17:16 2012

  14. Removal of organic films from solid surfaces using aqueous solutions of nonionic surfactants. 1: Experiments

    SciTech Connect

    Beaudoin, S.P.; Grant, C.S.; Carbonell, R.G. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Chemical Engineering

    1995-10-01

    An important step in the production of printed wiring assemblies (PWAs) is the postsolder removal of flux residues from the surface. Traditionally, this has been accomplished using CFC-113-based solutions, but the Montreal Protocol and the Clean Air Acts have forced the development of alternative cleaners. This is a study of the mechanisms by which aqueous solutions of a nonionic surfactant (pentaethylene glycol mono-n-dodecyl either (C{sub 12}E{sub 5})) remove films of flux residues (abietic acid in isopropyl alcohol) from PWA surfaces. Cleaning rates were studied in a rotating disk apparatus to control hydrodynamic conditions. The cleaning process followed a three-step mechanism. In the first stage, surfactant liquefies the organic by partitioning into the film. In the second and third stages, shear stresses at the PWA surface remove aggregates of the surfactant-laden liquefied AA from the bulk AA film and the PWA substrate, respectively.

  15. Different early rearing experiences have long term effects on cortical organization in captive chimpanzees (Pan troglodytes)

    PubMed Central

    Bogart, Stephanie L.; Bennett, Allyson J.; Schapiro, Steven J.; Reamer, Lisa A.; Hopkins, William D.

    2014-01-01

    Consequences of rearing history in chimpanzees (Pan troglodytes) have been explored in relation to behavioral abnormalities and cognition, however, little is known about the effects of rearing conditions on anatomical brain development. Human studies have revealed that experiences of maltreatment and neglect during infancy and childhood can have detrimental effects on brain development and cognition. In this study, we evaluated the effects of early rearing experience on brain morphology in 92 captive chimpanzees (ages 11-43) who were either reared by their mothers (n = 46) or in a nursery (n = 46) with age-group peers. Magnetic resonance brain images were analyzed with a processing program (BrainVISA) that extracts cortical sulci. We obtained various measurements from 11 sulci located throughout the brain, as well as whole brain gyrification and white and grey matter volumes. We found that mother-reared chimpanzees have greater global white-to-grey matter volume, more cortical folding and thinner grey matter within the cortical folds than nursery-reared animals. The findings reported here are the first to demonstrate that differences in early rearing conditions have significant consequences on brain morphology in chimpanzees and suggests potential differences in the development of white matter expansion and myelination. PMID:24206013

  16. Preliminary experiments on dynamic biology of micro-organisms to avoid any specific full-blown syndrome on humans

    NASA Astrophysics Data System (ADS)

    Meer, Sneer

    2002-06-01

    The aim of this paper is to apply an efficient system to detect, identify and quicken suppression of any dangerous micro-organism which threatens the health of the human body in any form. It is well known that some specimens of this kind of possess a specific energy related to their speed of division, toxin emissions and high-powered interaction with human and animal cells which have the capacity to provide certain deadly full-blown syndromes. Many problems relating to the above-mentioned properties have not been clarified to date, and it is vital to find a rapid and valid reply as soon as possible. Inter-disciplinary sciences directed us to start some experiments to solve such problems, considering that the human body is dotted with a multiple interactive system of energy release, a fact which can explain the source of the micro-organism's energy also, for their necessity to manifest their deadly pathology. From practical preliminary experiments with some micro-mechanical systems using light-microscopy, connected to video TV Recorder System, one obtains optical enlarged TV images of certain processes which indicated the right way towards our crucial target; ie: the preparation of safe vaccines and safe medicines. This will constitute a basic system to a void deadly manifestations of dangerous micro-organisms and/or even regular infections on earth and in space, a system which will probably be applied at the ISS Space Station and other future actions in space in long and very long flights. We look forward to applying this system of dynamic biology towards preparation of a real and valid vaccine(s) against HIV virus on AIDS diseases.

  17. REMOVAL OF HYDROPHOBIC MICRO?ORGANIC POLLUTANTS FROM MUNICIPAL WASTEWATER TREATMENT PLANT EFFLUENTS BY SORPTION ONTO SYNTHETIC POLYMERIC ADSORBENTS: UPFLOW COLUMN EXPERIMENTS

    Microsoft Academic Search

    V. S. Muhandiki; Y. Shimizu; Y. A. F. Adou; S. Matsui

    2008-01-01

    Continuous upflow bench?scale column experiments were carried out to investigate the use of a synthetic form polymer, polypropylene, and polypropylene coated with a thin layer of n?hexane as sorbents for hydrophobic organic compounds present in the effluent of municipal wastewater treatment plant. Two polycyclic aromatic hydrocarbons, namely, phenanthrene and fluorene, were selected as representative hydrophobic organic compounds for experimental purposes.

  18. Estimation of the blood flow through a peripheral organ (kidney) using the technique of isotope dilution after i.v. injection in animal experiments

    Microsoft Academic Search

    H.-D. Herrmann; H. Ludt; H. Palleske; G. Harbauer

    1973-01-01

    Summary Animal experiments were carried out to prove that it is possible to estimate the blood flow through peripheral organs with the isotope dilution technique after intravenous injection. It could be shown that the mathematical treatment of the dilution events in three mixing chambers in a row, presented in a foregoing paper, is valid also for the animal organism where

  19. Organizing national responses for rare blood disorders: the Italian experience with sickle cell disease in childhood

    PubMed Central

    2013-01-01

    Background Sickle cell disease (SCD) is the most frequent hemoglobinopathy worldwide but remains a rare blood disorder in most western countries. Recommendations for standard of care have been produced in the United States, the United Kingdom and France, where this disease is relatively frequent because of earlier immigration from Africa. These recommendations have changed the clinical course of SCD but can be difficult to apply in other contexts. The Italian Association of Pediatric Hematology Oncology (AIEOP) decided to develop a common national response to the rising number of SCD patients in Italy with the following objectives: 1) to create a national working group focused on pediatric SCD, and 2) to develop tailored guidelines for the management of SCD that could be accessed and practiced by those involved in the care of children with SCD in Italy. Methods Guidelines, adapted to the Italian social context and health system, were developed by 22 pediatric hematologists representing 54 AIEOP centers across Italy. The group met five times for a total of 128 hours in 22 months; documents and opinions were circulated via web. Results Recommendations regarding the prevention and treatment of the most relevant complications of SCD in childhood adapted to the Italian context and health system were produced. For each topic, a pathway of diagnosis and care is detailed, and a selection of health management issues crucial to Italy or different from other countries is described (i.e., use of alternatives for infection prophylaxis because of the lack of oral penicillin in Italy). Conclusions Creating a network of physicians involved in the day-to-day care of children with SCD is feasible in a country where it remains rare. Providing hematologists, primary and secondary care physicians, and caregivers across the country with web-based guidelines for the management of SCD tailored to the Italian context is the first step in building a sustainable response to a rare but emerging childhood blood disorder and in implementing the World Health Organization’s suggestion “to design (and) implement … comprehensive national integrated programs for the prevention and management of SCD". PMID:24139596

  20. Transformation and stabilization of pyrogenic organic matter in a temperate forest field experiment.

    PubMed

    Singh, Nimisha; Abiven, Samuel; Maestrini, Bernardo; Bird, Jeffrey A; Torn, Margaret S; Schmidt, Michael W I

    2014-05-01

    Pyrogenic organic matter (PyOM) decomposes on centennial timescale in soils, but the processes regulating its decay are poorly understood. We conducted one of the first studies of PyOM and wood decomposition in a temperate forest using isotopically labeled organic substrate, and quantified microbial incorporation and physico-chemical transformations of PyOM in situ. Stable-isotope (¹³C and ¹?N) enriched PyOM and its precursor wood were added to the soil at 2 cm depth at ambient (N0) and increased (N+) levels of nitrogen fertilization. The carbon (C) and nitrogen (N) of added PyOM or wood were tracked through soil to 15 cm depth, in physically separated soil density fractions and in benzene polycarboxylic acids (BPCA) molecular markers. After 10 months in situ, more PyOM-derived C (>99% of initial 13C-PyOM) and N (90% of initial ¹?N-PyOM) was recovered than wood derived C (48% of 13C-wood) and N(89% under N0 and 48% under N+). PyOM-C and wood-C migrated at the rate of 126 mm yr ?¹ with 3-4% of PyOMC and 4-8% of wood-C recovered below the application depth. Most PyOM C was recovered in the free light fraction(fLF) (74%), with 20% in aggregate-occluded and 6% in mineral associated fractions – fractions that typically have much slower turnover times. In contrast, wood C was recovered mainly in occluded (33%) or dense fraction (27%).PyOM addition induced loss of native C from soil (priming effect), particularly in fLF (13%). The total BPCA-C content did not change but after 10 months the degree of aromatic condensation of PyOM decreased, as determined by relative contribution of benzene hexa-carboxylic acid (B6CA) to the total BPCA C. Soil microbial biomass assimilated 6-10% of C from the wood, while PyOM contributions was negligible (0.14–0.18%). The addition of N had no effect on the dynamics of PyOM while limited effect on wood. PMID:25544969

  1. [Computer-based organization and documentation in orthopedics. A 5-year experience].

    PubMed

    Hess, T; Deimel, D; Fischer, R; Duchow, J

    1999-03-01

    In the orthopedic department of the University Hospital Homburg/Saar, we use since 1993 a computer-based system for clinics organisation and documentation of operations. Hardware consists of DOS/Windows PC's in a Novell-network. Our software is a combination of database-system for managing patient-data and a special coding program for ICD and IKPM-digits. Our experience shows that computer assisted clinic-management is an effective tool to help the surgeon in planning and documentation. Until now, we used the system for 31,500 patients and 8500 operations. A flexible software can meet the requirements both of the surgeons and administration. Moreover, in the University hospital Homburg/Saar, the different departments are linked by an Intranet with connection to other scientific networks and the Internet. PMID:10326203

  2. Time-of-night variations in the story-like organization of dream experience developed during rapid eye movement sleep.

    PubMed

    Cipolli, Carlo; Guazzelli, Mario; Bellucci, Claudia; Mazzetti, Michela; Palagini, Laura; Rosenlicht, Nicholas; Feinberg, Irwin

    2015-04-01

    This study aimed to investigate the cycles (2nd/4th) and duration-related (5/10 min) variations in the story-like organization of dream experience elaborated during rapid eye movement (REM) sleep. Dream reports were analysed using story grammar rules. Reports were provided by those subjects (14 of 22) capable of reporting a dream after each of the four awakenings provoked in 2 consecutive nights during REM sleep of the 2nd and 4th cycles, after periods of either 5 or 10 min, counterbalanced across the nights. Two researchers who were blind as to the sleep condition scored the dream reports independently. The values of the indicators of report length (measured as value of total word count) and of story-like organization of dream reports were matched taking time-of-night (2nd and 4th cycles) and REM duration (5 versus 10 min) as factors. Two-way analyses of variance showed that report length increased significantly in 4th-cycle REM sleep and nearly significantly for longer REM duration, whereas the number of dream-stories per report did not vary. The indices of sequential (number of statements describing the event structure developed in the story) and hierarchical (number of episodes per story) organization increased significantly only in dream-stories reported after 10 min of 4th-cycle REM sleep. These findings indicate that the characteristics of structural organization of dream-stories vary along with time of night, and suggest that the elaboration of a long and complex dream-story requires a fairly long time and the availability of a great amount of cognitive resources to maintain its continuity and coherence. PMID:25307048

  3. Charge Photogeneration Experiments and Theory in Aggregated Squaraine Donor Materials for Improved Organic Solar Cell Efficiencies

    NASA Astrophysics Data System (ADS)

    Spencer, Susan Demetra

    Fossil fuel consumption has a deleterious effect on humans, the economy, and the environment. Renewable energy technologies must be identified and commercialized as quickly as possible so that the transition to renewables can happen at a minimum of financial and societal cost. Organic photovoltaic cells offer an inexpensive and disruptive energy technology, if the scientific challenges of understanding charge photogeneration in a bulk heterojunction material can be overcome. At RIT, there is a strong focus on creating new materials that can both offer fundamentally important scientific results relating to quantum photophysics, and simultaneously assist in the development of strong candidates for future commercialized technology. In this presentation, the results of intensive materials characterization of a series of squaraine small molecule donors will be presented, as well as a full study of the fabrication and optimization required to achieve >4% photovoltaic cell efficiency. A relationship between the molecular structure of the squaraine and its ability to form nanoscale aggregates will be explored. Squaraine aggregation will be described as a unique optoelectronic probe of the structure of the bulk heterojunction. This relationship will then be utilized to explain changes in crystallinity that impact the overall performance of the devices. Finally, a predictive summary will be given for the future of donor material research at RIT.

  4. Thermal alteration experiments on organic matter in recent marine sediments as a model for petroleum genesis

    NASA Technical Reports Server (NTRS)

    Baedecker, M. J.; Ikan, R.; Ishiwatari, R.; Kaplan, I. R.

    1977-01-01

    The fate of naturally occurring lipids and pigments in a marine sediment exposed to elevated temperatures was studied. Samples of a young marine sediment from Tanner Basin, California, were heated to a series of temperatures (65-200 C) for varying periods of time (7-64 days). The sediment was analyzed prior to and after heating for pigments, isoprenoid compounds, alcohols, fatty acids, and hydrocarbons. Structural changes caused by heating unextractable organic material (kerogen) were also studied, and the significance of the results for understanding petroleum genesis is considered. Among other results, fatty acids and hydrocarbons increased in abundance although there appeared to be no obvious precursor-to-product relationship via simple decarboxylation reactions. Chlorins were partially converted into porphyrins. The phytyl side chain of pheophytin was initially preserved intact by reduction of the phytyl double bond, but later converted to a variety of isoprenoid compounds including alkanes. Thermal grafting of components onto kerogen occurred as well as structural changes caused by heat.

  5. Sub-bandgap absorption in organic solar cells: experiment and theory.

    PubMed

    Beenken, Wichard J D; Herrmann, Felix; Presselt, Martin; Hoppe, Harald; Shokhovets, Sviatoslav; Gobsch, Gerhard; Runge, Erich

    2013-10-21

    Most high-performance organic solar cells involve bulk-heterojunctions in order to increase the active donor-acceptor interface area. The power conversion efficiency depends critically on the nano-morphology of the blend and the interface. Spectroscopy of the sub-bandgap region, i.e., below the bulk absorption of the individual components, provides unique opportunities to study interface-related properties. We present absorption measurements in the sub-bandgap region of bulk heterojunctions made of poly(3-hexylthiophene-2,5-diyl) as an electron donor and [6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM) as an electron acceptor and compare them with quantum-chemical calculations and recently published data on the external quantum efficiency (EQE). The very weak absorption of the deep sub-bandgap region measured by the ultra-sensitive Photothermal Deflection Spectroscopy (PDS) features Urbach tails, polaronic transitions, conventional excitons, and possibly charge-transfer states. The quantum-chemical calculations allow characterizing some of the unsettled spectral features. PMID:23929440

  6. Characterization of dissolved organic matter during reactive transport: A column experiment with spectroscopic detection

    NASA Astrophysics Data System (ADS)

    Vazquez, A.; Hernández, S.; Rasmussen, C.; Chorover, J.

    2010-12-01

    Al and Fe oxy-hydroxide minerals have been implicated in dissolved organic matter (DOM) stabilization. DOM solutions from a Pinus ponderosa forest floor (PPDOM) were used to irrigate polypropylene columns, 3.2 cm long by 0.9 cm diameter (total volume 2.0 cm3), that were packed with quartz sand (QS), gibbsite-quartz sand (Al-QS), and goethite-quartz sand (Fe-QS) mixtures. To investigate the mobilization and fractionation of DOM during reactive transport, effluent solutions were characterized by UV-Vis absorbance and excitation-emission matrix (EEM) fluorescence spectroscopies. Magnitude of PPDOM sorption followed the trend Al-QS > Fe-QS > QS during the initial transport. Effluent pH values suggest that ligand exchange is a primary mechanism for PPDOM sorption onto oxy-hydroxide minerals. Low molar absorptivity values were observed in effluent solutions of early pore volumes, indicating preferential mobilization of compounds with low aromatic character. Compounds traditionally characterized by EEM spectroscopy as being more highly humified were favorably absorbed onto the gibbsite and goethite surfaces. Humification index values (HIX) were also correlated with DOM aromaticity. HIX results suggest that the presence of low mass fractions of oxy-hydroxide minerals affect the preferential uptake of high molar mass constituents of PPDOM during reactive transport.

  7. How to organize a neutron imaging user lab? 13 years of experience at PSI, CH

    NASA Astrophysics Data System (ADS)

    Lehmann, E. H.; Vontobel, P.; Frei, G.; Kuehne, G.; Kaestner, A.

    2011-09-01

    PSI has a relatively long tradition in neutron imaging since the first trials were done at its formerly existing research reactor SAPHIR with film methods. This reactor source was replaced after its shutdown in 1994 by the spallation neutron source SINQ in 1996, driven by the 590 MeV cyclotron for protons with presently up to 2.3 mA beam current. One of the first experimental devices at SINQ was the thermal neutron imaging facility NEUTRA, which was designed from scratch and has been the first device of its kind at a spallation source. Until now, NEUTRA has been successfully in use for many investigations in a wide range of studies covering fuel cell research, environmental behavior of plants, nuclear fuel inspection and the research on cultural heritage objects. It has been the host of PhD projects for students from all over Europe for years. In a previous meeting it has been offered as a European reference facility. Some of its features were really adapted to the layout of new installations. In 2004, it was possible to initiate the project of a second beam line at SINQ for imaging with cold neutrons. Previous studies have shown the potential of this option in order to broaden the user profile and to extend the scientific basis for neutron imaging. It was inaugurated with a workshop at PSI in 2005. The user service was started at the facility ICON in 2006. Beside the setup, installation and optimization of the facilities, the organization of the user program plays an important role. The two neutron imaging beam lines are equal installations at SINQ among the 14 scientific devices. Therefore, the user approach is organized via "calls for proposals", which are sent out each half year via the "Digital User Office (DUO)" (see http://duo.web.psi.ch). The evaluation of the proposals is done by the "Advisory Committee for Neutron Imaging (ACNI)" consisting of 6 external and PSI internal members. Further requests are given by industrial collaborations. This beam time allocation is handled more directly and in time in order to fulfill the companies' demands. Here, the confidentiality plays a more important role than in scientific studies that are done with the aim of a free publication. It has been possible to earn money regularly from the industrial projects in order to cover the salary cost of some positions within the NIAG group. The permanent improvement of the methodology and performance in neutron imaging is a third major activity of the NIAG team. Running projects in this direction are the permanent insert of a grating interferometry device, improved energy selection with the help of single graphite crystals and utilization of the beam line BOA at SINQ for the energy range between 4 and 15 Å.

  8. Internal Marketing, Negative Experiences, and Volunteers'Commitment to Providing High-Quality Services in a UK Helping and Caring Charitable Organization

    Microsoft Academic Search

    Roger Bennett; Anna Barkensjo

    2005-01-01

    This empirical study examined the effects of “negative'' contact experiences with beneficiaries on charity volunteers' job satisfaction and organizational commitment within a helping and caring charitable organization that for 3.5 years had operated an internal marketing program. It was hypothesized that negative experiences downwardly moderated (i) the impact of the charity's internal market activities on satisfaction and commitment, and (ii)

  9. Synthesis and Resolution of the Atropisomeric 1,1'-Bi-2-Naphthol: An Experiment in Organic Synthesis and 2-D NMR Spectroscopy

    ERIC Educational Resources Information Center

    Mak, Kendrew K. W.

    2004-01-01

    NMR spectroscopy is presented. It is seen that the experiment regarding the synthesis and resolution of 1,1'-Bi-2-naphtol presents a good experiment for teaching organic synthesis and NMR spectroscopy and provides a strategy for obtaining enantiopure compounds from achiral starting materials.

  10. Enantiomeric Resolution of [Plus or Minus] Mandelic Acid by (1R,2S)-(--)-Ephedrine: An Organic Chemistry Laboratory Experiment Illustrating Stereoisomerism

    ERIC Educational Resources Information Center

    Baar, Marsha R.; Cerrone-Szakal, Andrea L.

    2005-01-01

    The experiment involving enantiomeric resolution, as an illustration of chiral technology, is an excellent early organic chemistry lab experiment. The success of this enantiomeric resolution can be judged by melting point, demonstrated by [plus or minus]-mandelic acid-(1R,2S)-(--)-ephedrine system.

  11. Identification of significant transport processes for organic micropollutant classes during soil aquifer treatment (SAT) - a controlled field experiment

    NASA Astrophysics Data System (ADS)

    Nödler, Karsten; Licha, Tobias; Sauter, Martin

    2010-05-01

    Supplementing existing water resources with alternative sources of water is a challenge in semi-arid areas, as deterioration of water quality must be avoided. Soil aquifer treatment (SAT) can greatly improve the quality of the injected water by attenuation of organic pollutants via sorption and degradation processes. However, only little is known about the specific transport processes of organic micropollutants under artificial recharge conditions. Organic micropollutants such as pharmaceuticals and their metabolites exhibit a wide range of chemical properties and may undergo very different environmental processes resulting in specific reactions within specified environments. In the presented study fate and transport processes of 25 organic micropollutants (iodinated contrast media, antihypertensive agents, antibiotics, anticonvulsants, lipid regulators, anti-inflammatories, antihistamines and analgesics) were investigated under SAT conditions in a controlled field experiment. Secondary treated effluent (STE) containing the compounds of interest was introduced into the aquifer by an infiltration pond and shallow wells in the vicinity were used for water quality monitoring. By means of strategic sampling procedure and a specialized multi-residue analytical method based on high-performance liquid chromatography / tandem mass spectrometry (LC/MS-MS) 3 main transport processes were identified: 1. Transport of non-polar compounds according to their respective octanol-water distribution coefficient (Kow) 2. Cation exchange 3. Colloidal transport Identification of transport processes 2 & 3 was not expected to act as a transport controlling process. Results of the positively charged beta-blockers sotalol, atenolol and metoprolol gave clear evidence for cation exchange processes of the compounds with the aquifer material. Correlation of turbidity and concentrations of macrolide antibiotics (clarithromycin, erythromycin and roxithromycin) demonstrated the colloidal transport of the respective compounds. Concentrations of almost all micropollutants decreased with increasing soil passage. However, since compounds transported by processes 2 & 3 can be re-mobilized by changing water chemistry, the importance of a diligent characterisation of aquifer material and raw water is apparent for risk assessment. The experiments were conducted within the context of the project GABARDINE, funded by the European Commission.

  12. Immediate Dissemination of Student Discoveries to a Model Organism Database Enhances Classroom-Based Research Experiences

    PubMed Central

    Wiley, Emily A.; Stover, Nicholas A.

    2014-01-01

    Use of inquiry-based research modules in the classroom has soared over recent years, largely in response to national calls for teaching that provides experience with scientific processes and methodologies. To increase the visibility of in-class studies among interested researchers and to strengthen their impact on student learning, we have extended the typical model of inquiry-based labs to include a means for targeted dissemination of student-generated discoveries. This initiative required: 1) creating a set of research-based lab activities with the potential to yield results that a particular scientific community would find useful and 2) developing a means for immediate sharing of student-generated results. Working toward these goals, we designed guides for course-based research aimed to fulfill the need for functional annotation of the Tetrahymena thermophila genome, and developed an interactive Web database that links directly to the official Tetrahymena Genome Database for immediate, targeted dissemination of student discoveries. This combination of research via the course modules and the opportunity for students to immediately “publish” their novel results on a Web database actively used by outside scientists culminated in a motivational tool that enhanced students’ efforts to engage the scientific process and pursue additional research opportunities beyond the course. PMID:24591511

  13. Impact of Ag and Al?O? nanoparticles on soil organisms: in vitro and soil experiments.

    PubMed

    Fajardo, C; Saccà, M L; Costa, G; Nande, M; Martin, M

    2014-03-01

    In vitro analyses were conducted to assess the impact of Al2O3 and Ag nanoparticles on two common soil bacteria, Bacillus cereus and Pseudomonas stutzeri. Al2O3 nanoparticles did not show significant toxicity at any dose or time assayed, whereas exposure to 5 mg L(-1) Ag nanoparticles for 48 h caused bactericidal effects. Moreover, alterations at the morphological level were observed by transmission electron microscopy (TEM); Ag but not Al2O3 nanoparticles evoked the entrance of B. cereus cells in an early sporulation stage and both nanoparticles penetrated P. stutzeri cells. At the molecular level, a dramatic increase (8.2-fold) in katB gene expression was found in P. stutzeri following Al2O3 nanoparticles exposure, indicative of an oxidative stress-defence system enhancement in this bacterium. In the microcosm experiment, using two different natural soils, Al2O3 or Ag nanoparticles did not affect the Caenorhabditis elegans toxicity endpoints growth, survival, or reproduction. However, differences in microbial phylogenetic compositions were detected by fluorescence in situ hybridization (FISH). The use of katB- and pykA-based sequences showed that the microbial transcriptional response to nanoparticle exposure decreased, suggesting a decrease in cellular activity. These changes were attributable to both the nanoparticles treatment and soil characteristics, highlighting the importance of considering the soil matrix on a case by case basis. PMID:24374587

  14. Evaluating Re-Os systematics in organic-rich sedimentary rocks in response to petroleum generation using hydrous pyrolysis experiments

    USGS Publications Warehouse

    Rooney, A.D.; Selby, D.; Lewan, M.D.; Lillis, P.G.; Houzay, J.-P.

    2012-01-01

    Successful application of the 187Re–187Os geochronometer has enabled the determination of accurate and precise depositional ages for organic-rich sedimentary rocks (ORS) as well as establishing timing constraints of petroleum generation. However, we do not fully understand the systematics and transfer behaviour of Re and Os between ORS and petroleum products (e.g., bitumen and oil). To more fully understand the behaviour of Re–Os systematics in both source rocks and petroleum products we apply hydrous pyrolysis to two immature hydrocarbon source rocks: the Permian Phosphoria Formation (TOC = 17.4%; Type II-S kerogen) and the Jurassic Staffin Formation (TOC = 2.5%; Type III kerogen). The laboratory-based hydrous pyrolysis experiments were carried out for 72 h at 250, 300, 325 and 350 °C. These experiments provided us with whole rock, extracted rock and bitumen and in some cases expelled oil and asphaltene for evaluation of Re–Os isotopic and elemental abundance. The data from these experiments demonstrate that the majority (>95%) of Re and Os are housed within extracted rock and that thermal maturation does not result in significant transfer of Re or Os from the extracted rock into organic phases. Based on existing thermodynamic data our findings suggest that organic chelating sites have a greater affinity for the quadravalent states of Re and Os than sulphides. Across the temperature range of the hydrous pyrolysis experiments both whole rock and extracted rock 187Re/188Os ratios show small variations (3.3% and 4.7%, for Staffin, respectively and 6.3% and 4.9% for Phosphoria, respectively). Similarly, the 187Os/188Os ratios show only minor variations for the Staffin and Phosphoria whole rock and extracted rock samples (0.6% and 1.4% and 1.3% and 2.2%). These isotopic data strongly suggest that crude oil generation through hydrous pyrolysis experiments does not disturb the Re–Os systematics in ORS as supported by various studies on natural systems. The elemental abundance data reveal limited transfer of Re and Os into the bitumen from a Type III kerogen in comparison to Type II-S kerogen (0.02% vs. 3.7%), suggesting that these metals are very tightly bound in Type III kerogen structure. The 187Os/188Os data from the pyrolysis generated Phosphoria bitumens display minor variation (4%) across the experimental temperatures, with values similar to that of the source rock. This indicates that the isotopic composition of the bitumen reflects the isotopic composition of the source rock at the time of petroleum generation. These data further support the premise that the Os isotopic composition of oils and bitumens can be used to fingerprint petroleum deposits to specific source rocks. Oil generated through the hydrous pyrolysis experiments does not contain appreciable quantities of Re or Os (~120 and ~3 ppt, respectively), in contrast to natural oils (2–50 ppb and 34–288 ppt for Re and Os, respectively), which may suggest that kinetic parameters are fundamental to the transfer of Re and Os from source rocks to oils. From this we hypothesise that, at the temperatures employed in hydrous pyrolysis, Re and Os are assimilated into the extracted rock as a result of cross-linking reactions.

  15. A local coherent-state approximation to system-bath quantum dynamics

    NASA Astrophysics Data System (ADS)

    Martinazzo, Rocco; Nest, Mathias; Saalfrank, Peter; Tantardini, Gian Franco

    2006-11-01

    A novel quantum method to deal with typical system-bath dynamical problems is introduced. Subsystem discrete variable representation and bath coherent-state sets are used to write down a multiconfigurational expansion of the wave function of the whole system. With the help of the Dirac-Frenkel variational principle, simple equations of motion—a kind of Schrödinger-Langevin equation for the subsystem coupled to (pseudo) classical equations for the bath—are derived. True dissipative dynamics at all times is obtained by coupling the bath to a secondary, classical Ohmic bath, which is modeled by adding a friction coefficient in the derived pseudoclassical bath equations. The resulting equations are then solved for a number of model problems, ranging from tunneling to vibrational relaxation dynamics. Comparison of the results with those of exact, multiconfiguration time-dependent Hartree calculations in systems with up to 80 bath oscillators shows that the proposed method can be very accurate and might be of help in studying realistic problems with very large baths. To this end, its linear scaling behavior with respect to the number of bath degrees of freedom is shown in practice with model calculations using tens of thousands of bath oscillators.

  16. A local coherent-state approximation to system-bath quantum dynamics

    SciTech Connect

    Martinazzo, Rocco; Nest, Mathias; Saalfrank, Peter; Tantardini, Gian Franco [Department of Physical Chemistry and Electrochemistry, University of Milan, Via Golgi 19, 20133 Milan (Italy) and CIMAINA, University of Milan, Via Golgi 19, 20133 Milan (Italy); Institut fuer Chemie, Universitaet Potsdam, Karl-Liebknecht-Strasse 24-25, 14476 Potsdam (Germany); Department of Physical Chemistry and Electrochemistry, University of Milan, Via Golgi 19, 20133 Milan (Italy); CIMAINA, University of Milan, Via Golgi 19, 20133 Milan (Italy) and CNR Institute of Molecular Science and Technology, Via Golgi 19, 20133 Milan (Italy)

    2006-11-21

    A novel quantum method to deal with typical system-bath dynamical problems is introduced. Subsystem discrete variable representation and bath coherent-state sets are used to write down a multiconfigurational expansion of the wave function of the whole system. With the help of the Dirac-Frenkel variational principle, simple equations of motion--a kind of Schroedinger-Langevin equation for the subsystem coupled to (pseudo) classical equations for the bath--are derived. True dissipative dynamics at all times is obtained by coupling the bath to a secondary, classical Ohmic bath, which is modeled by adding a friction coefficient in the derived pseudoclassical bath equations. The resulting equations are then solved for a number of model problems, ranging from tunneling to vibrational relaxation dynamics. Comparison of the results with those of exact, multiconfiguration time-dependent Hartree calculations in systems with up to 80 bath oscillators shows that the proposed method can be very accurate and might be of help in studying realistic problems with very large baths. To this end, its linear scaling behavior with respect to the number of bath degrees of freedom is shown in practice with model calculations using tens of thousands of bath oscillators.

  17. Modeling the stability of electroless plating bath--diffusion of nickel colloidal particles from the plating frontier.

    PubMed

    Yin, X; Hong, L; Chen, B-H; Ko, T-M

    2003-06-01

    Electroless nickel (EN) plating is a process in which Ni2+ ions are reduced by hydrogen atoms adsorbed at a fresh Ni surface. However, detaching of a handful of tiny Ni metal particles from a substrate causes the entrance of these particles into the plating solution. The metal particles offer very reactive surfaces for the reduction of Ni2+ ions, which in turn aggravates the detachment, causing a self-accelerated cycle. Eventually the plating solution will be subject to an overwhelming precipitation of Ni black. This paper proposes a one-dimensional diffusion model to explain the dependence of the bath stability on the plating time under different bath loadings. This mathematical model contains Vd, defined as the decomposition volume, a measure to judge chemical stability of a plating solution. To obtain Vd experimentally, a PdCl2 solution was purposely introduced into a model solution (the addition leads to immediate generation of metal particles) until the very moment of onset of massive deposition of colloidal Ni. The Vd data from the experiment were then used to perform simulation in order to complete the model proposed. Other than the effects of bath loadings and plating time, an adsorption model was also created to describe the temperature effect. To coordinate the adsorption model, l-cysteine was used as an adsorbate that plays a deactivation role. The under bump metallization process on patterned silicon wafers has been used to support the main theme of this study. PMID:16256584

  18. Multitracer experiment to evaluate the attenuation of selected organic micropollutants in a karst aquifer.

    PubMed

    Hillebrand, Olav; Nödler, Karsten; Sauter, Martin; Licha, Tobias

    2015-02-15

    The increasing pressure on drinking water resources necessitates an efficient management of potential and actual drinking water resources. Karst aquifers play a key role in the supply of the world's population with drinking water. Around one quarter of all drinking water is produced from these types of aquifers. Unfortunately due to the aquifer characteristics with extremely high hydraulic conductivities and short residence times, these systems are vulnerable to contamination. For successful management, a fundamental understanding of mass transport and attenuation processes with respect to potential contaminants is vital. In this study, a multitracer experiment was performed in a karst aquifer in SW-Germany for determining the attenuation capacity of a karst environment by assessing the environmental fate of selected relevant micropollutants. Uranine, acesulfame and carbamazepine were injected into a sinkhole as reference tracers together with the reactive compounds atenolol, caffeine, cyclamate, ibuprofen and paracetamol (also known as acetaminophen). The breakthrough of the tracers was monitored at a karst spring at a distance of ca. 3 km. The breakthrough curves of the reactive compounds were interpreted relative to the reference substances. No significant retardation was found for any of the investigated micropollutants. The determined half-lives of the reactive compounds range from 38 to 1,400 h (i.e. persistent within the investigation period) in the following order (from high to no observed attenuation): paracetamol>atenolol?ibuprofen>caffeine?cyclamate. The attenuation rates are generally in agreement with studies from other environmental compartments. The occurrence of the biotransformation product atenolol acid served as evidence for in-situ biodegradation within the aquifer system. PMID:25460968

  19. Epitaxy of Rodlike Organic Molecules on Sheet Silicates—A Growth Model Based on Experiments and Simulations

    PubMed Central

    2011-01-01

    During the last years, self-assembled organic nanostructures have been recognized as a proper fundament for several electrical and optical applications. In particular, phenylenes deposited on muscovite mica have turned out to be an outstanding material combination. They tend to align parallel to each other forming needlelike structures. In that way, they provide the key for macroscopic highly polarized emission, waveguiding, and lasing. The resulting anisotropy has been interpreted so far by an induced dipole originating from the muscovite mica substrate. Based on a combined experimental and theoretical approach, we present an alternative growth model being able to explain molecular adsorption on sheet silicates in terms of molecule?surface interactions only. By a comprehensive comparison between experiments and simulations, we demonstrate that geometrical changes in the substrate surface or molecule lead to different molecular adsorption geometries and needle directions which can be predicted by our growth model. PMID:21309570

  20. Assessment of potential climate change impacts on peatland dissolved organic carbon release and drinking water treatment from laboratory experiments.

    PubMed

    Tang, R; Clark, J M; Bond, T; Graham, N; Hughes, D; Freeman, C

    2013-02-01

    Catchments draining peat soils provide the majority of drinking water in the UK. Over the past decades, concentrations of dissolved organic carbon (DOC) have increased in surface waters. Residual DOC can cause harmful carcinogenic disinfection by-products to form during water treatment processes. Increased frequency and severity of droughts combined with and increased temperatures expected as the climate changes, have potentials to change water quality. We used a novel approach to investigate links between climate change, DOC release and subsequent effects on drinking water treatment. We designed a climate manipulation experiment to simulate projected climate changes and monitored releases from peat soil and litter, then simulated coagulation used in water treatment. We showed that the 'drought' simulation was the dominant factor altering DOC release and affected the ability to remove DOC. Our results imply that future short-term drought events could have a greater impact than increased temperature on DOC treatability. PMID:23207497

  1. Qubit interference at avoided crossings: The role of driving shape and bath coupling

    E-print Network

    Ralf Blattmann; Sigmund Kohler; Peter Hänggi

    2014-09-18

    We derive the structure of the Landau-Zener-St\\"uckelberg-Majorana (LZSM) interference pattern for a qubit that experiences quantum dissipation and is additionally subjected to time-periodic but otherwise general driving. A spin-boson Hamiltonian serves as model which we treat with a Bloch-Redfield master equation in Floquet basis. It predicts a peak structure that depends sensitively on the operator through which the qubit couples to the bath. The Fourier transforms of the LZSM patterns exhibit arc structures which reflect the shape of the driving. These features are captured by an effective time-independent Bloch equation which provides an analytical solution. Moreover, we determine the decay of these arcs as a function of dissipation strength and temperature.

  2. [History of hot spring bath treatment in China].

    PubMed

    Hao, Wanpeng; Wang, Xiaojun; Xiang, Yinghong; Gu Li, A Man; Li, Ming; Zhang, Xin

    2011-07-01

    As early as the 7th century B.C. (Western Zhou Dynasty), there is a recording as 'spring which contains sulfur could treat disease' on the Wentang Stele written by WANG Bao. Wenquan Fu written by ZHANG Heng in the Easten Han Dynasty also mentioned hot spring bath treatment. The distribution of hot springs in China has been summarized by LI Daoyuan in the Northern Wei Dynasty in his Shuijingzhu which recorded hot springs in 41 places and interpreted the definition of hot spring. Bencao Shiyi (by CHEN Cangqi, Tang Dynasty) discussed the formation of and indications for hot springs. HU Zai in the Song Dynasty pointed out distinguishing hot springs according to water quality in his book Yuyin Conghua. TANG Shenwei in the Song Dynasty noted in Jingshi Zhenglei Beiji Bencao that hot spring bath treatment should be combined with diet. Shiwu Bencao (Ming Dynasty) classified hot springs into sulfur springs, arsenicum springs, cinnabar springs, aluminite springs, etc. and pointed out their individual indications. Geologists did not start the work on distribution and water quality analysis of hot springs until the first half of the 20th century. There are 972 hot springs in Wenquan Jiyao (written by geologist ZHANG Hongzhao and published in 1956). In July 1982, the First National Geothermal Conference was held and it reported that there were more than 2600 hot springs in China. Since the second half of the 20th century, hot spring sanatoriums and rehabilitation centers have been established, which promoted the development of hot spring bath treatment. PMID:22169492

  3. Resummed memory kernels in generalized system-bath master equations

    NASA Astrophysics Data System (ADS)

    Mavros, Michael G.; Van Voorhis, Troy

    2014-08-01

    Generalized master equations provide a concise formalism for studying reduced population dynamics. Usually, these master equations require a perturbative expansion of the memory kernels governing the dynamics; in order to prevent divergences, these expansions must be resummed. Resummation techniques of perturbation series are ubiquitous in physics, but they have not been readily studied for the time-dependent memory kernels used in generalized master equations. In this paper, we present a comparison of different resummation techniques for such memory kernels up to fourth order. We study specifically the spin-boson Hamiltonian as a model system bath Hamiltonian, treating the diabatic coupling between the two states as a perturbation. A novel derivation of the fourth-order memory kernel for the spin-boson problem is presented; then, the second- and fourth-order kernels are evaluated numerically for a variety of spin-boson parameter regimes. We find that resumming the kernels through fourth order using a Padé approximant results in divergent populations in the strong electronic coupling regime due to a singularity introduced by the nature of the resummation, and thus recommend a non-divergent exponential resummation (the "Landau-Zener resummation" of previous work). The inclusion of fourth-order effects in a Landau-Zener-resummed kernel is shown to improve both the dephasing rate and the obedience of detailed balance over simpler prescriptions like the non-interacting blip approximation, showing a relatively quick convergence on the exact answer. The results suggest that including higher-order contributions to the memory kernel of a generalized master equation and performing an appropriate resummation can provide a numerically-exact solution to system-bath dynamics for a general spectral density, opening the way to a new class of methods for treating system-bath dynamics.

  4. Monitoring bathing beach water quality using composite sampling.

    PubMed

    Reicherts, Jeffrey D; Emerson, Charles William

    2010-09-01

    Michigan water quality standards for public bathing beaches require local health departments to collect and analyze a minimum of three water samples for Escherichia coli during each sampling event. The geometric mean number of E. coli colonies is then compared to the 300 colonies per 100 ml standard to determine compliance. This article compares the results of the currently mandated procedure to a composite sampling method, whereby the three samples are mixed in equal volumes and analyzed once. This effectively replaces the geometric mean of the individual sample results with an arithmetic mean. Although arithmetic means are more affected by outliers, this sensitivity to high concentrations is more health conservative than the geometric mean. During the 2007 sampling season, nine bathing beaches were monitored once each week. Three individual point samples and a composite sample were analyzed for each sampling event. No statistically significant differences in bacteria concentrations were found between composite sample analysis and the arithmetic mean of individual point sample analyses. No violations were detected in the 2007 sampling season, so using historical data, a retrospective analysis was performed on samples gathered at nine bathing beaches in Kalamazoo County, Michigan during the years 2001-2007. The arithmetic mean of the three samples taken at each site served as a surrogate composite sample. The benefits of compositing the three samples were investigated assuming a 2/3 reduction in analytical costs. In the traditional sampling method, three individual samples were obtained and analyzed once in every 3-week period during the summer season, whereas compositing was simulated by taking the arithmetic mean of each week's results. The results of this retrospective cost analysis indicates that ten to 14 violations would have been missed using the less frequent traditional sampling and analysis methodology. Composite sampling is a cost-saving alternative to traditional sampling techniques that can be more protective of public health, particularly when the savings are applied to increased numbers of samples in time or space. PMID:19609694

  5. Resummed memory kernels in generalized system-bath master equations.

    PubMed

    Mavros, Michael G; Van Voorhis, Troy

    2014-08-01

    Generalized master equations provide a concise formalism for studying reduced population dynamics. Usually, these master equations require a perturbative expansion of the memory kernels governing the dynamics; in order to prevent divergences, these expansions must be resummed. Resummation techniques of perturbation series are ubiquitous in physics, but they have not been readily studied for the time-dependent memory kernels used in generalized master equations. In this paper, we present a comparison of different resummation techniques for such memory kernels up to fourth order. We study specifically the spin-boson Hamiltonian as a model system bath Hamiltonian, treating the diabatic coupling between the two states as a perturbation. A novel derivation of the fourth-order memory kernel for the spin-boson problem is presented; then, the second- and fourth-order kernels are evaluated numerically for a variety of spin-boson parameter regimes. We find that resumming the kernels through fourth order using a Padé approximant results in divergent populations in the strong electronic coupling regime due to a singularity introduced by the nature of the resummation, and thus recommend a non-divergent exponential resummation (the "Landau-Zener resummation" of previous work). The inclusion of fourth-order effects in a Landau-Zener-resummed kernel is shown to improve both the dephasing rate and the obedience of detailed balance over simpler prescriptions like the non-interacting blip approximation, showing a relatively quick convergence on the exact answer. The results suggest that including higher-order contributions to the memory kernel of a generalized master equation and performing an appropriate resummation can provide a numerically-exact solution to system-bath dynamics for a general spectral density, opening the way to a new class of methods for treating system-bath dynamics. PMID:25106575

  6. Verification of impact of morning showering and mist sauna bathing on human physiological functions and work efficiency during the day.

    PubMed

    Lee, Soomin; Fujimura, Hiroko; Shimomura, Yoshihiro; Katsuura, Tetsuo

    2014-11-12

    Recently, a growing number in Japan are switching to taking baths in the morning (morning bathing). However, the effects of the morning bathing on human physiological functions and work efficiency have not yet been revealed. Then, we hypothesized that the effect of morning bathing on physiological functions would be different from those of night bathing. In this study, we measured the physiological functions and work efficiency during the day following the morning bathing (7:10-7:20) including showering, mist sauna bathing, and no bathing as a control. Ten male healthy young adults participated in this study as the subjects. We evaluated the rectal temperature (Tre), skin temperature (Tsk), heart rate (HR), heart rate variability (HRV), blood pressure (BP), the relative power density of the alpha wave (?-wave ratio) of electroencephalogram, alpha attenuation coefficient (AAC), and the error rate of the task performance. As a result, we found that the HR after the mist sauna bathing was significantly lower than those after no bathing rest 3 (11:00). Furthermore, we verified that the ?-wave ratio of the Pz after the mist sauna bathing was significantly lower than those after no bathing during the task 6 (15:00). On the other hand, the ?-wave ratio of the Pz after the mist sauna bathing was significantly higher than those after showering during the rest 3 (11:00). Tsk after the mist sauna bathing was higher than those after the showering at 9:00 and 15:00. In addition, the error rate of the task performance after the mist sauna bathing was lower than those after no bathing and showering at 14:00. This study concludes that a morning mist sauna is safe and maintains both skin temperature compared to other bathing methods. Moreover, it is presumed that the morning mist sauna bathing improves work efficiency comparing other bathing methods during the task period of the day following the morning bathing. PMID:25388947

  7. Generalized Energy Equipartition in Harmonic Oscillators Driven by Active Baths

    NASA Astrophysics Data System (ADS)

    Maggi, Claudio; Paoluzzi, Matteo; Pellicciotta, Nicola; Lepore, Alessia; Angelani, Luca; Di Leonardo, Roberto

    2014-12-01

    We study experimentally and numerically the dynamics of colloidal beads confined by a harmonic potential in a bath of swimming E. coli bacteria. The resulting dynamics is well approximated by a Langevin equation for an overdamped oscillator driven by the combination of a white thermal noise and an exponentially correlated active noise. This scenario leads to a simple generalization of the equipartition theorem resulting in the coexistence of two different effective temperatures that govern dynamics along the flat and the curved directions in the potential landscape.

  8. Dissociation rate of bromine diatomics in an argon heat bath

    NASA Technical Reports Server (NTRS)

    Razner, R.; Hopkins, D.

    1973-01-01

    The evolution of a collection of 300 K bromine diatomics embedded in a heat bath of argon atoms at 1800 K was studied by computer, and a dissociation-rate constant for the reaction Br2 + BR + Ar yields Br + Ar was determined. Previously published probability distributions for energy and angular momentum transfers in classical three-dimensional Br2-Ar collisions were used in conjunction with a newly developed Monte Carlo scheme for this purpose. Results are compared with experimental shock-tube data and the predictions of several other theoretical models. A departure from equilibrium is obtained which is significantly greater than that predicted by any of these other theories.

  9. Transport of thermal water from well to thermal baths

    NASA Astrophysics Data System (ADS)

    Montegrossi, Giordano; Vaselli, Orlando; Tassi, Franco; Nocentini, Matteo; Liccioli, Caterina; Nisi, Barbara

    2013-04-01

    The main problem in building a thermal bath is having a hot spring or a thermal well located in an appropriate position for customer access; since Roman age, thermal baths were distributed in the whole empire and often road and cities were built all around afterwards. Nowadays, the perspectives are changed and occasionally the thermal resource is required to be transported with a pipeline system from the main source to the spa. Nevertheless, the geothermal fluid may show problems of corrosion and scaling during transport. In the Ambra valley, central Italy, a geothermal well has recently been drilled and it discharges a Ca(Mg)-SO4, CO2-rich water at the temperature of 41 °C, that could be used for supplying a new spa in the surrounding areas of the well itself. The main problem is that the producing well is located in a forest tree ca. 4 km far away from the nearest structure suitable to host the thermal bath. In this study, we illustrate the pipeline design from the producing well to the spa, constraining the physical and geochemical parameters to reduce scaling and corrosion phenomena. The starting point is the thermal well that has a flow rate ranging from 22 up to 25 L/sec. The thermal fluid is heavily precipitating calcite (50-100 ton/month) due to the calcite-CO2 equilibrium in the reservoir, where a partial pressure of 11 bar of CO2 is present. One of the most vexing problems in investigating scaling processed during the fluid transport in the pipeline is that there is not a proper software package for multiphase fluid flow in pipes characterized by such a complex chemistry. As a consequence, we used a modified TOUGHREACT with Pitzer database, arranged to use Darcy-Weisbach equation, and applying "fictitious" material properties in order to give the proper y- z- velocity profile in comparison to the analytical solution for laminar fluid flow in pipes. This investigation gave as a result the lowest CO2 partial pressure to be kept in the pipeline (nearly 2.5 bar) to avoid uncontrolled calcite precipitation, and accordingly the pipeline path was designed. Non-linear phenomena that may originate calcite precipitation, such as phase separation and pressure waves, were discussed. The pipeline and the thermal bath are planned to be built next year.

  10. Generalized energy equipartition in harmonic oscillators driven by active baths

    E-print Network

    Claudio Maggi; Matteo Paoluzzi; Nicola Pellicciotta; Alessia Lepore; Luca Angelani; Roberto Di Leonardo

    2014-11-06

    We study experimentally and numerically the dynamics of colloidal beads confined by a harmonic potential in a bath of swimming E. coli bacteria. The resulting dynamics is well approximated by a Langevin equation for an overdamped oscillator driven by the combination of a white thermal noise and an exponentially correlated active noise. This scenario leads to a simple generalization of the equipartition theorem resulting in the coexistence of two different effective temperatures that govern dynamics along the flat and the curved directions in the potential landscape.

  11. Generalized energy equipartition in harmonic oscillators driven by active baths.

    PubMed

    Maggi, Claudio; Paoluzzi, Matteo; Pellicciotta, Nicola; Lepore, Alessia; Angelani, Luca; Di Leonardo, Roberto

    2014-12-01

    We study experimentally and numerically the dynamics of colloidal beads confined by a harmonic potential in a bath of swimming E. coli bacteria. The resulting dynamics is well approximated by a Langevin equation for an overdamped oscillator driven by the combination of a white thermal noise and an exponentially correlated active noise. This scenario leads to a simple generalization of the equipartition theorem resulting in the coexistence of two different effective temperatures that govern dynamics along the flat and the curved directions in the potential landscape. PMID:25526168

  12. Photoluminescence of chemical bath deposited CdS films

    SciTech Connect

    Gracia-Jimenez, M.; Gomez, E.; Martinez, G.; Martinez, J.L.; Zehe, A.

    1984-12-01

    Photoluminescence spectra of chemical bath deposited CdS films have been taken. It is shown that the emission line reaching from 0.8 to 2.4 eV depends on the stoichiometry of the films. The stoichiometry is controlled either by changing the pH of the working solution during the deposition process or by carrying out a thermal annealing in air on the films. The most stoichiometric CdS films present a green edge emission line which persists eve at room temperature. This line is identified as a radiative transition between a Cd complex and an S vacancy.

  13. The Asymptotic Cooling of Heat-Bath Algorithmic Cooling

    E-print Network

    Sadegh Raeisi; Michele Mosca

    2014-12-02

    The purity of quantum states is a key requirement for many quantum applications. Improving the purity is limited by fundamental laws of thermodynamics. Here we are probing the fundamental limits for a natural approach to this problem, namely heat-bath algorithmic cooling(HBAC). The existence of the cooling limit for HBAC techniques was proved by Schulman et al. in, the limit however remained unknown for the past decade. Here for the first time we find this limit. In the context of quantum thermodynamics, this corresponds to the maximum extractable work from the quantum system.

  14. Metabolic model of lead kinetics based upon measured organ burdens during chronic exposure experiments with infant and juvenile baboons

    SciTech Connect

    Mallon, R.P.

    1983-01-01

    A mathematical model of the kinetics of lead metabolism in the infant and juvenile baboon has been developed based upon data from chronic exposure experiments in this non-human primate. The model of lead metabolism presents in quantitative terms the rates of uptake, distribution and elimination that lead may undergo during its passage through the organism. The organs of accumulation are defined as compartments, each of which is defined as a quantity of tissue that behaves kinetically like a distinct, homogeneous, well mixed pool in terms of lead concentration. The flow of lead between the compartments of accumulation is described by a series of differential equations. Elimination rate coefficients, expressed in terms of the biological half-life for each compartment have been estimated. The model describes the observed build-up and accumulation of lead in the major body compartments of the infant and juvenile baboon. The model indicates that: the biological half-life of lead in blood of the very young animals is shorter than that of the older animals; there is a higher rate of uptake of lead in the soft tissues and in the bones of rapidly growing animals; and there is an inverse relationship between the quality of lead administered and the amount of lead absorbed, i.e., as exposure increases the rate of absorption decreases. The model derived for the older animals accurately predicts the accumulation and retention of lead in adult humans under normal exposure conditions.

  15. Bath water contamination with legionella and nontuberculous mycobacteria in 24-hour home baths, hot springs, and public bathhouses of Nagano Prefecture, Japan.

    PubMed

    Kobayashi, Michiko; Oana, Kozue; Kawakami, Yoshiyuki

    2014-01-01

    Bath water samples were collected from 116 hot springs, 197 public bathhouses, and 38 24-hour home baths in Nagano Prefecture, Japan, during the period of April 2009 to November 2011, for determining the presence and extent of contamination with Legionella and nontuberculous mycobacteria. Cultures positive for Legionella were observed in 123 of the 3,314 bath water samples examined. The distribution and abundance of Legionella and/or combined contamination with Legionella and nontuberculous mycobacteria were investigated to clarify the contamination levels. The abundance of Legionella was demonstrated to correlate considerably with the levels of combined contamination with Legionella and nontuberculous mycobacteria. Legionella spp. were obtained from 61% of the water samples from 24-hour home baths, but only from 3% of the samples from public bathhouses and hot springs. This is despite the fact that a few outbreaks of Legionnaires' disease in Nagano Prefecture as well as other regions of Japan have been traced to bath water contamination. The comparatively higher rate of contamination of the 24-hour home baths is a matter of concern. It is therefore advisable to routinely implement good maintenance of the water basins, particularly of the 24-hour home baths. PMID:25056073

  16. A microscopic model for noise induced transport: Heat-bath nonlinearly driven by external white noise

    SciTech Connect

    Ghosh, Pradipta; Shit, Anindita; Chattopadhyay, Sudip [Department of Chemistry, Bengal Engineering and Science University, Shibpur, Howrah 711103 (India); Chaudhuri, Jyotipratim Ray [Department of Physics, Katwa College, Katwa, Burdwan 713130 (India)

    2011-03-15

    This work explores the observation that, even in the absence of a net externally applied bias, a symmetric homogeneous system coupled linearly to two heat baths is capable of producing unidirectional motion simply by nonlinearly driving one of the heat baths by an external Gaussian white noise. This is quite contrary to the traditional observation that, in order to obtain a net drift current, a state-dependent dissipation, which is a consequence of nonlinear system-bath coupling, is ubiquitous.

  17. Grain size dependence of the bandgap in chemical bath deposited CdS thin films

    Microsoft Academic Search

    A. Cortes; H. Gómez; R. E. Marotti; G. Riveros; E. A. Dalchiele

    2004-01-01

    CdS thin films were deposited by chemical bath deposition onto glass substrates from chemical bath containing cadmium sulfate, thiourea and ammonia at pH=10.5. The temperature of the bath was maintained at either 75°C or 85°C and under mill stirring. After that the samples were annealed in air at 450°C. Analysis of the as-deposited thin films by energy dispersive X-ray analysis

  18. Chemical bath deposition of Cds buffer layer for GIGS solar cells

    Microsoft Academic Search

    Y. Hashimoto; N. Kohara; T. Negami; N. Nishitani; T. Wada

    1998-01-01

    We investigated the chemical bath deposition of US thin flims on the Cu(In,Ga)Se2 (GIGS) absorber layers and glasses. The process of the chemical bath deposition of US layer affected the performance of the CIGS solar cells. The CdS layers were deposited on the CIGS film from CdI2, thiourea (NH2CSNHn2) and ammonia solutions. The influence of pH on the chemical bath

  19. Total Quantum Zeno effect and Intelligent States for a two level system in a squeezed bath

    E-print Network

    D. Mundarain; M. Orszag; J. Stephany

    2006-10-20

    In this work we show that by frequent measurements of adequately chosen observables, a complete suppression of the decay in an exponentially decaying two level system interacting with a squeezed bath is obtained. The observables for which the effect is observed depend on the the squeezing parameters of the bath. The initial states which display Total Zeno Effect are intelligent states of two conjugate observables associated to the electromagnetic fluctuations of the bath.

  20. Hydrogen impurities in chemical bath deposited CdS

    SciTech Connect

    Weber, M.; Krauser, J.; Weidinger, A.; Bruns, J.; Fischer, C.H.; Bohne, W.; Roehrich, J.; Scheer, R. [Hahn-Meitner-Inst., Berlin (Germany)] [Hahn-Meitner-Inst., Berlin (Germany)

    1999-06-01

    Chemical bath deposition is a well-established process for the fabrication of thin CdS films for electro-optic devices. The authors investigate the various impurities in this material with emphasis on hydrogen-related compounds. Nuclear reaction analysis provides hydrogen depth profiles of chemically deposited CdS with mean concentrations up to 12 atom % hydrogen. Using photoelectron spectroscopy only a part of this amount can be ascribed to bonds with other impurities. The distribution of hydrogen in CdS thin films exhibits a clear dependence on the concentration of precursor substances in the bath and the deposition time. The accumulation of hydrogen in the film during processing has been determined and may be explained by a diffusion process along grain boundaries of the polycrystalline CdS. The authors demonstrate the variation of hydrogen and other impurity concentrations upon vacuum annealing. As a result of their investigations, they suggest a single hydrogen species is included during the deposition process in order to account for the hydrogen surplus found. A chemical reaction capable of supplying the observed individual hydrogen species is presented.

  1. Lunar Surface Systems Wet-Bath Design Evaluation

    NASA Technical Reports Server (NTRS)

    Thompson, Shelby; Szabo, Rich; Howard, Robert

    2010-01-01

    The goal of the current evaluation was to examine five different wet-bath architectural design concepts. The primary means of testing the concepts required participants to physically act-out a number of functional tasks (e.g., shaving, showering, changing clothes, maintenance) in order to give judgments on the affordance of the volume as based on the design concepts. Each of the concepts was designed in such a way that certain features were exploited - for example, a concept may have a large amount of internal stowage, but minimum amount of usable space to perform tasks. The results showed that the most preferred concept was one in which stowage and usable space were balanced. This concept allowed for a moderate amount of stowage with some suggested redesign, but would not preclude additional personal items such as clothing. This concept also allowed for a greater distance to be achieved between the toilet and the sink with minimum redesign, which was desirable. Therefore, the all-in-one (i.e., toilet, sink, and shower all occupying a single volume) wet-bath concept seemed to be a viable solution in which there is a minimal amount of overall volume available with certain lunar habitat configurations.

  2. Gauging a Quantum Heat Bath with Dissipative Landau-Zener Transitions

    SciTech Connect

    Wubs, Martijn; Kohler, Sigmund; Haenggi, Peter [Institut fuer Physik, Universitaet Augsburg, Universitaetsstrasse 1, D-86135 Augsburg (Germany); Saito, Keiji [Department of Physics, Graduate School of Science, University of Tokyo, Tokyo 113-0033 (Japan); Kayanuma, Yosuke [Department of Mathematical Science, Graduate School of Engineering, Osaka Prefecture University, Sakai 599-8531 (Japan)

    2006-11-17

    We calculate the exact Landau-Zener transition probabilities for a qubit with an arbitrary linear coupling to a bath at zero temperature. The final quantum state exhibits a peculiar entanglement between the qubit and the bath. In the special case of diagonal coupling, the bath does not influence the transition probability, whatever the speed of the Landau-Zener sweep. It is proposed to use Landau-Zener transitions to determine both the reorganization energy and the integrated spectral density of the bath. Possible applications include circuit QED and molecular nanomagnets.

  3. Occurrence of thermotolerant Campylobacter spp. and adenoviruses in Finnish bathing waters and purified sewage effluents.

    PubMed

    Hokajärvi, Anna-Maria; Pitkänen, Tarja; Siljanen, Henri M P; Nakari, Ulla-Maija; Torvinen, Eila; Siitonen, Anja; Miettinen, Ilkka T

    2013-03-01

    A total of 50 Finnish bathing water samples and 34 sewage effluent samples originating from 17 locations were studied in the summers of 2006 and 2007. Campylobacter were present in 58% and adenoviruses in 12% of all bathing water samples; 53% of all sewage effluent samples were positive for Campylobacter spp. and 59% for adenoviruses. C. jejuni was the most common Campylobacter species found and human adenovirus serotype 41 was the most common identified adenovirus type. Bathing water temperature displayed a significant negative relationship with the occurrence of Campylobacter. One location had identical pulsed-field gel electrophoresis patterns of C. coli isolates in the bathing water and in sewage effluent, suggesting that sewage effluent was the source of C. coli at this bathing site. The counts of faecal indicator bacteria were not able to predict the presence of Campylobacter spp. or adenoviruses in the bathing waters. Thus the observed common presence of these pathogens in Finnish sewage effluents and bathing waters may represent a public health risk. The low water temperature in Finland may enhance the prevalence of Campylobacter in bathing waters. More attention needs to be paid to minimizing the concentrations of intestinal pathogens in bathing waters. PMID:23428555

  4. Electron transfer in a two-level system within a Cole-Davidson vitreous bath

    SciTech Connect

    Zarea, Mehdi, E-mail: m-zarea@northwestern.edu; Ratner, Mark A.; Wasielewski, Michael R. [Argonne-Northwestern Solar Energy Research (ANSER) Center, Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113 (United States)] [Argonne-Northwestern Solar Energy Research (ANSER) Center, Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113 (United States)

    2014-01-14

    We study electron transfer (ET) in a two level quantum system coupled to a glassy viscous bath. The bath is modeled by the Cole-Davidson (CD) spectral density. The ET in this model is compared to the ET in a normal Drude-Debye (DD) model. It is shown that at low temperatures and when the coupling to the bath is weak, the viscous bath preserves the quantum coherence for a longer time. However in the strong coupling regime, the tunneling rate is higher in the CD. In the classical high temperature limit the difference between the CD and DD models is negligible.

  5. Genomic Insights into Methanotrophy: The Complete Genome Sequence of Methylococcus capsulatus (Bath)

    PubMed Central

    2004-01-01

    Methanotrophs are ubiquitous bacteria that can use the greenhouse gas methane as a sole carbon and energy source for growth, thus playing major roles in global carbon cycles, and in particular, substantially reducing emissions of biologically generated methane to the atmosphere. Despite their importance, and in contrast to organisms that play roles in other major parts of the carbon cycle such as photosynthesis, no genome-level studies have been published on the biology of methanotrophs. We report the first complete genome sequence to our knowledge from an obligate methanotroph, Methylococcus capsulatus (Bath), obtained by the shotgun sequencing approach. Analysis revealed a 3.3-Mb genome highly specialized for a methanotrophic lifestyle, including redundant pathways predicted to be involved in methanotrophy and duplicated genes for essential enzymes such as the methane monooxygenases. We used phylogenomic analysis, gene order information, and comparative analysis with the partially sequenced methylotroph Methylobacterium extorquens to detect genes of unknown function likely to be involved in methanotrophy and methylotrophy. Genome analysis suggests the ability of M. capsulatus to scavenge copper (including a previously unreported nonribosomal peptide synthetase) and to use copper in regulation of methanotrophy, but the exact regulatory mechanisms remain unclear. One of the most surprising outcomes of the project is evidence suggesting the existence of previously unsuspected metabolic flexibility in M. capsulatus, including an ability to grow on sugars, oxidize chemolithotrophic hydrogen and sulfur, and live under reduced oxygen tension, all of which have implications for methanotroph ecology. The availability of the complete genome of M. capsulatus (Bath) deepens our understanding of methanotroph biology and its relationship to global carbon cycles. We have gained evidence for greater metabolic flexibility than was previously known, and for genetic components that may have biotechnological potential. PMID:15383840

  6. Dinitrogen fixation and dissolved organic nitrogen fueled primary production and particulate export during the VAHINE mesocosms experiment (New Caledonia lagoon)

    NASA Astrophysics Data System (ADS)

    Berthelot, H.; Moutin, T.; L'Helguen, S.; Leblanc, K.; Hélias, S.; Grosso, O.; Leblond, N.; Charrière, B.; Bonnet, S.

    2015-03-01

    In the oligotrophic ocean characterized by nitrate (NO3-) depletion in surface waters, dinitrogen (N2) fixation and dissolved organic nitrogen (DON) can represent significant nitrogen (N) sources for the ecosystem. Here we deployed in New Caledonia large in situ mesocosms in order to investigate (1) the contribution of N2 fixation and DON use to primary production (PP) and particle export and (2) the fate of the freshly produced particulate organic N (PON) i.e. whether it is preferentially accumulated and recycled in the water column or exported out of the system. The mesocosms were fertilized with phosphate (P) in order to prevent P-limitation and promote N2 fixation. The diazotrophic community was dominated by diatoms-diazotrophs associations (DDAs) during the first part of the experiment for 10 days (P1) followed by the unicellular N2-fixing cyanobacteria UCYN-C the 9 last days (P2) of the experiment. N2 fixation rates averaged 9.8 ± 4.0 and 27.7 ± 8.6 nM d-1 during P1 and P2, respectively. NO3- concentrations (< 40 nM) in the mesocosms were a negligible source of N indicating that N2 fixation was the main driver of new production all along the experiment. The contribution of v fixation to PP was not significantly different (p > 0.05) during P1 (9.0 ± 3.3%) and P2 (12.6 ± 6.1%). However, the e ratio that quantifies the efficiency of a system to export particulate organic carbon (POCexport) compared to PP (e ratio = POCexport/PP) was significantly higher (p < 0.05) during P2 (39.7 ± 24.9%) than during P1 (23.9 ± 20.2%) indicating that the production sustained by UCYN-C was more efficient at promoting C export than the production sustained by DDAs. During P1, PON was stable and the total amount of N provided by N2 fixation (0.10 ± 0.02 ?M) was not significantly different (p > 0.05) from the total amount of PON exported (0.10 ± 0.04 ?M), suggesting a rapid and probably direct export of the recently fixed N2 by the DDAs. During P2, both PON concentrations and PON export increased in the mesocosms by a factor 1.5-2. Unlike in P1, this PON production was not totally explained by the new N provided by N2 fixation. The use of DON, whose concentrations decreased significantly (p < 0.05) from 5.3 ± 0.5 ?M to 4.4 ± 0.5 ?M, appeared to be the missing N source. The DON consumption of about 0.9 ?M during P2 is even higher than the total amount of new N brought by N2 fixation (about 0.25 ?M) during the same period. These results suggest that while DDAs mainly rely on N2 fixation for their N requirement, both N2 fixation and DON can be significant N-sources for primary production and particulate export following UCYN-C blooms in the New Caledonia lagoon and by extension in the N-limited Ocean where similar events are likely to occur.

  7. Decomposition of old organic matter as a result of deeper active layers in a snow depth manipulation experiment

    PubMed Central

    Taneva, Lina; Trumbore, Susan E.; Welker, Jeffrey M.

    2010-01-01

    A snow addition experiment in moist acidic tussock tundra at Toolik Lake, Alaska, increased winter snow depths 2–3 m, and resulted in a doubling of the summer active layer depth. We used radiocarbon (?14C) to (1) determine the age of C respired in the deep soils under control and deepened active layer conditions (deep snow drifts), and (2) to determine the impact of increased snow and permafrost thawing on surface CO2 efflux by partitioning respiration into autotrophic and heterotrophic components. ?14C signatures of surface respiration were higher in the deep snow areas, reflecting a decrease in the proportion of autotrophic respiration. The radiocarbon age of soil pore CO2 sampled near the maximum mid-July thaw depth was approximately 1,000 years in deep snow treatment plots (45–55 cm thaw depth), while CO2 from the ambient snow areas was ~100 years old (30-cm thaw depth). Heterotrophic respiration ?14C signatures from incubations were similar between the two snow depths for the organic horizon and were extremely variable in the mineral horizon, resulting in no significant differences between treatments in either month. Radiocarbon ages of heterotrophically respired C ranged from <50 to 235 years BP in July mineral soil samples and from 1,525 to 8,300 years BP in August samples, suggesting that old soil C in permafrost soils may be metabolized upon thawing. In the surface fluxes, this old C signal is obscured by the organic horizon fluxes, which are significantly higher. Our results indicate that, as permafrost in tussock tundra ecosystems of arctic Alaska thaws, carbon buried up to several thousands of years ago will become an active component of the carbon cycle, potentially accelerating the rise of CO2 in the atmosphere. Electronic supplementary material The online version of this article (doi:10.1007/s00442-009-1556-x) contains supplementary material, which is available to authorized users. PMID:20084398

  8. Climate effect on soil enzyme activities and dissolved organic carbon in mountain calcareous soils: a soil-transplant experiment

    NASA Astrophysics Data System (ADS)

    Puissant, Jérémy; Cécillon, Lauric; Mills, Robert T. E.; Gavazov, Konstantin; Robroek, Bjorn J. M.; Spiegelberger, Thomas; Buttler, Alexandre; Brun, Jean-Jacques

    2013-04-01

    Mountain soils store huge amounts of carbon as soil organic matter (SOM) which may be highly vulnerable to the strong climate changes that mountain areas currently experience worldwide. Climate modifications are expected to impact microbial activity which could change the rate of SOM decomposition/accumulation, thereby questioning the net C source/sink character of mountain soils. To simulate future climate change expected in the 21st century in the calcareous pre-Alps, 15 blocks (30 cm deep) of undisturbed soil were taken from a mountain pasture located at 1400 m a.s.l. (Marchairuz, Jura, Switzerland) and transplanted into lysimeters at the same site (control) and at two other sites located at 1000 m a.s.l. and 600 m a.s.l. (5 replicates per site). This transplantation experiment which started in 2009 simulates a climate warming with a temperature increase of 4° C and a decreased humidity of 40 % at the lowest site. In this study, we used soil extracellular enzyme activities (EEA) as functional indicators of SOM decomposition to evaluate the effect of climate change on microbial activity and SOM dynamics along the seasons. Dissolved organic carbon (DOC) was also measured to quantify the assimilable carbon for microorganism. In autumn 2012, a first sampling step out of four (winter, spring and summer 2013) has been realized. We extracted 15 cm deep soil cores from each transplant (x15) and measured (i) DOC and (ii) the activities of nine different enzymes. Enzymes were chosen to represent the degradation of the most common classes of biogeochemical compounds in SOM. ?-glucosidase, ?-D-cellubiosidase, ?-Xylosidase, N-acetyl-?-glucosaminidase, leucine aminopeptidase, lipase, phenoloxidase respectively represented the degradation of sugar, cellulose, hemicellulose, chitin, protein, lipid and lignin. Moreover, the fluorescein diacetate (FDA) hydrolysis was used to provide an estimate of global microbial activity and phosphatase was used to estimate phosphorus mineralization. The autumn results showed no differences for global microbial activity along the climate gradient (0.37 nKatal g-1 dry soil), no differences and a very low activity for leucine aminopeptidase and ?-glucosidase and ?-Xylosidase (about 0.09 nKatal g-1 dry soil) and no differences for cellulose, chitin and phosphorus mineralization. Conversely, we measured a greater activity at the highest elevation site for lipase and phenoloxydase (ANOVA test, p

  9. Whole-lake experiments reveal the fate of terrestrial particulate organic carbon in benthic food webs of shallow lakes.

    PubMed

    Scharnweber, K; Syväranta, J; Hilt, S; Brauns, M; Vanni, M J; Brothers, S; Köhler, J; Knezevi?-Jari?, J; Mehner, T

    2014-06-01

    Lake ecosystems are strongly linked to their terrestrial surroundings by material and energy fluxes across ecosystem boundaries. However, the contribution of terrestrial particulate organic carbon (tPOC) from annual leaf fall to lake food webs has not yet been adequately traced and quantified. In this study, we conducted whole-lake experiments to trace artificially added tPOC through the food webs of two shallow lakes of similar eutrophic status, but featuring alternative stable regimes (macrophyte rich vs. phytoplankton dominated). Lakes were divided with a curtain, and maize (Zea mays) leaves were added, as an isotopically distinct tPOC source, into one half of each lake. To estimate the balance between autochthonous carbon fixation and allochthonous carbon input, primary production and tPOC and tDOC (terrestrial dissolved organic carbon) influx were calculated for the treatment sides. We measured the stable isotope ratios of carbon (delta13C) of about 800 samples from all trophic consumer levels and compared them between lake sides, lakes, and three seasons. Leaf litter bag experiments showed that added maize leaves were processed at rates similar to those observed for leaves from shoreline plants, supporting the suitability of maize leaves as a tracer. The lake-wide carbon influx estimates confirmed that autochthonous carbon fixation by primary production was the dominant carbon source for consumers in the lakes. Nevertheless, carbon isotope values of benthic macroinvertebrates were significantly higher with maize additions compared to the reference side of each lake. Carbon isotope values of omnivorous and piscivorous fish were significantly affected by maize additions only in the macrophyte-dominated lake and delta13C of zooplankton and planktivorous fish remained unaffected in both lakes. In summary, our results experimentally demonstrate that tPOC in form of autumnal litterfall is rapidly processed during the subsequent months in the food web of shallow lakes and is channeled to secondary and tertiary consumers predominantly via the benthic pathways. A more intense processing of tPOC seems to be connected to a higher structural complexity in littoral zones, and hence may differ between shallow lakes of alternative stable states. PMID:25039215

  10. Organic contaminant distributions in sediments, polychaetes (Nereis virens) and American lobster (Homarus americanus) from a laboratory food chain experiment.

    PubMed

    Pruell, R J; Taplin, B K; McGovern, D G; McKinney, R; Norton, S B

    2000-02-01

    A laboratory experiment was conducted to investigate the transfer of organic contaminants from an environmentally contaminated marine sediment through a simple marine food chain. The infaunal polychaete, Nereis virens, was exposed to contaminated sediment collected from the Passaic River, NJ, USA, for 70 days. These polychaetes were then fed to the American lobster, Homarus americanus, for up to 112 days. Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), 2,4,6,8-tetrachlorodibenzothiophene (TCDT), polychlorinated biphenyls (PCBs), and several chlorinated pesticides were accumulated by polychaetes following exposure to the contaminated sediment. Some of these contaminants were also accumulated by lobsters which were exposed to the contaminated sediment and/or fed contaminated polychaetes. Only the lesser chlorinated PCDDs and PCDFs (mostly tetra- and pentachlorinated congeners) and 2,4,6,8-TCDT were detected in the polychaetes and lobster. Significant alterations were noted in the PCB patterns found in both species, particularly the lobster. The non-ortho-substituted PCBs (such as congeners 77 and 126) became enriched in the PCB mixtures of the polychaetes and especially the lobsters relative to the sediment, probably because these congeners were not metabolized. These congeners and the 2,3,7,8-tetrachlorodibenzo-p-dioxin toxicity equivalents of the PCB mixtures were enriched by a factor of about six in the lobsters relative to the sediment. Elimination of PCB congeners containing vicinal hydrogens in the meta-para region is consistent with cytochrome P450IIB-type metabolism. Based on the concentration trends for some PCB congeners and chlorinated pesticide ratios measured in the lobsters during this experiment, it appears that this metabolic system is inducible in the American lobster. PMID:11444012

  11. The jumping ring experiment

    NASA Astrophysics Data System (ADS)

    Baylie, M.; Ford, P. J.; Mathlin, G. P.; Palmer, C.

    2009-01-01

    The jumping ring experiment has become central to liquid nitrogen shows given as part of the outreach and open day activities carried out within the University of Bath. The basic principles of the experiment are described as well as the effect of changing the geometry of the rings and their metallurgical state. In general, aluminium rings are used, but the effect of using copper rings is briefly discussed.

  12. The University of Bath's Materials Research Centre brings together academic expertise with international industrial, academic and stakeholder partners to carry out research in different

    E-print Network

    Burton, Geoffrey R.

    The University of Bath's Materials Research Centre brings together academic expertise please contact us using the details overleaf. University of Bath Materials research at Bath #12 currently being undertaken at Bath: The University of Bath is one of the UK's leading research intensive

  13. Asymptotic Bound for Heat-Bath Algorithmic Cooling

    NASA Astrophysics Data System (ADS)

    Raeisi, Sadegh; Mosca, Michele

    2015-03-01

    The purity of quantum states is a key requirement for many quantum applications. Improving the purity is limited by fundamental laws of thermodynamics. Here, we are probing the fundamental limits for a natural approach to this problem, namely, heat-bath algorithmic cooling (HBAC). The existence of the cooling limit for HBAC techniques was proved by Schulman, Mor, and Weinstein. A bound for this value was found by Elias et al. and numerical testing supported the hypothesis that their bound may be the actual limit. A proof or disproof of whether their bound was the actual limit remained open for the past decade. Here, for the first time, we prove this limit. In the context of quantum thermodynamics, this corresponds to the maximum extractable work from the quantum system. We also establish, in the case of higher dimensional reset systems, how the performance of HBAC depends on the energy spectrum of the reset system.

  14. Quantum heat bath for spin-lattice dynamics

    NASA Astrophysics Data System (ADS)

    Woo, C. H.; Wen, Haohua; Semenov, A. A.; Dudarev, S. L.; Ma, Pui-Wai

    2015-03-01

    Quantization of spin-wave excitations necessitates the reconsideration of the classical fluctuation-dissipation relation (FDR) used for temperature control in spin-lattice dynamics simulations of ferromagnetic metals. In this paper, Bose-Einstein statistics is used to reinterpret the Langevin dynamics of both lattice and spins, allowing quantum statistics to be mimicked in canonical molecular dynamics simulations. The resulting quantum heat baths are tested by calculating the specific heats and magnetization over a wide temperature range, from 0 K to above the Curie temperature, with molecular dynamics (MD), spin dynamics (SD), and spin-lattice dynamics (SLD) simulations. The results are verified with experimental data and available theoretical analysis. Comparison with classical results also shows the importance of quantization effects for spin excitations in all the ferromagnetically ordered configurations.

  15. Sliding wear behavior of salt bath nitrocarburized medium carbon steel

    NASA Astrophysics Data System (ADS)

    Srinivasan, P. Bala; Krishnakumar, C. V.; Krishnaraj, N.

    2002-10-01

    Salt bath nitrocarburizing is a well-known thermochemical diffusion process for enhancing the tribological and corrosion properties of ferrous components. The current work describes the role of a compound layer developed during nitrocarburizing, both in the ferritic and austenitic regimes of Fe-N-C system, on the sliding wear behavior of a medium carbon steel. The wear behavior of the nitrocarburized steel discs was assessed by the pin-on-disc tests (ASTM G 99-99) under different normal loads running against a hardened SAE52100 pin. It was observed that the compound layer on the surface not only controlled the wear rate but also resisted the adhesive wear/transfer of material from pin to disc, aside from providing low-friction coefficients.

  16. Bath salts and synthetic cathinones: An emerging designer drug phenomenon

    PubMed Central

    German, Christopher L.; Fleckenstein, Annette E.; Hanson, Glen R.

    2014-01-01

    The synthetic cathinones are an emerging class of designer drugs abused for psychostimulant and hallucinogenic effects similar to cocaine, methylenedioxymethamphetamine (MDMA), or other amphetamines. Abuse of synthetic cathinones, frequently included in products sold as ‘bath salts’, became prevalent in early 2009, leading to legislative classification throughout Europe in 2010 and schedule I classification within the United States in 2011. Recent pre-clinical and clinical studies indicate dysregulation of central monoamine systems are a principal mechanism of synthetic cathinone action and presumably underlie the behavioral effects and abuse liability associated with these drugs. This review provides insight into the development of synthetic cathinones as substances of abuse, current patterns of their abuse, known mechanisms of their action and toxicology, and the benefits and drawbacks of their classification. PMID:23911668

  17. Chemical bath ZnSe thin films: deposition and characterisation

    NASA Astrophysics Data System (ADS)

    Lokhande, C. D.; Patil, P. S.; Ennaoui, A.; Tributsch, H.

    1998-01-01

    The zinc selenide (ZnSe) thin films have been deposited by a simple and inexpensive chemical bath deposition (CBD) method. The selenourea was used as a selenide ion source. The ZnSe films have been characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDAX), Rutherford back scattering (RBS), and optical absorption. The as-deposited ZnSe films on various substrates are found to be amorphous and contain O2 and N2 in addition to Zn and Se. The optical band gap of the film is estimated to be 2.9 eV. The films are photoactive as evidenced by time resolved microwave conductivity (TRMC).

  18. Are "bath salts" the next generation of stimulant abuse?

    PubMed

    Winder, Gerald Scott; Stern, Nathan; Hosanagar, Avinash

    2013-01-01

    "Bath salts" are stimulants with high abuse potential that are known to contain agents such as 3,4-methylenedioxypyrovalerone and 4-methylmethcathinone (mephedrone). They are marketed locally and through online retailers as legitimate products in order to evade legal control and facilitate widespread distribution. They have been present in Europe since 2007 but are now becoming a burgeoning presence in American hospitals. Though preliminary efforts are underway in the United States to restrict their usage and distribution, there remains a general unawareness on the part of physicians regarding the drugs' physiological effects. While they mimic the effects of other known stimulants, they are not detected on standard urine screens. We present a clinical case that illustrates a typical pattern of usage along with a description of their basic chemistry, appearance, methods of delivery, withdrawal and intoxication characteristics, treatment recommendations, and areas for further research. PMID:22445773

  19. Bath salts and synthetic cathinones: an emerging designer drug phenomenon.

    PubMed

    German, Christopher L; Fleckenstein, Annette E; Hanson, Glen R

    2014-02-27

    Synthetic cathinones are an emerging class of designer drugs abused for psychostimulant and hallucinogenic effects similar to cocaine, methylenedioxymethamphetamine (MDMA), or other amphetamines. Abuse of synthetic cathinones, frequently included in products sold as 'bath salts', became prevalent in early 2009, leading to legislative classification throughout Europe in 2010 and schedule I classification within the United States in 2011. Recent pre-clinical and clinical studies indicate that dysregulation of central monoamine systems is a principal mechanism of synthetic cathinone action and presumably underlie the behavioral effects and abuse liability associated with these drugs. This review provides insight into the development of synthetic cathinones as substances of abuse, current patterns of their abuse, known mechanisms of their action and toxicology, and the benefits and drawbacks of their classification. PMID:23911668

  20. Asymptotic bound for heat-bath algorithmic cooling.

    PubMed

    Raeisi, Sadegh; Mosca, Michele

    2015-03-13

    The purity of quantum states is a key requirement for many quantum applications. Improving the purity is limited by fundamental laws of thermodynamics. Here, we are probing the fundamental limits for a natural approach to this problem, namely, heat-bath algorithmic cooling (HBAC). The existence of the cooling limit for HBAC techniques was proved by Schulman, Mor, and Weinstein. A bound for this value was found by Elias et al. and numerical testing supported the hypothesis that their bound may be the actual limit. A proof or disproof of whether their bound was the actual limit remained open for the past decade. Here, for the first time, we prove this limit. In the context of quantum thermodynamics, this corresponds to the maximum extractable work from the quantum system. We also establish, in the case of higher dimensional reset systems, how the performance of HBAC depends on the energy spectrum of the reset system. PMID:25815911

  1. Language organization and temporal correlations in the spiking activity of an excitable laser: Experiments and model comparison

    NASA Astrophysics Data System (ADS)

    Rubido, Nicolas; Tiana-Alsina, Jordi; Torrent, M. C.; Garcia-Ojalvo, Jordi; Masoller, Cristina

    2011-08-01

    We introduce a method, based on symbolic analysis, to characterize the temporal correlations of the spiking activity exhibited by excitable systems. The technique is applied to the experimentally observed dynamics of a semiconductor laser with optical feedback operating in the low-frequency fluctuations regime, where the laser intensity displays irregular trains of sudden dropouts that can be interpreted as excitable pulses. Symbolic analysis transforms the series of interdropout time intervals into sequences of words, which represent the local ordering of a certain (small) number of those intervals. We then focus on the transition probabilities between pairs of words, showing that certain transitions are overrepresented (resulting in others being underrepresented) with respect to the surrogate series, provided the laser injection current is above a critical value. These experimental observations are in very good agreement with numerical simulations of the delay-differential Lang-Kobayashi model that is commonly used to describe this laser system, which supports the fact that the language organization reported here is generic and not a particular feature of the specific laser employed or the experimental time series analyzed. We also present results of simulations of the phenomenological nondelayed Eguia-Mindlin-Giudici(EMG) model and find that in this model the agreement between the experiments and the simulations is good at a qualitative, but not at a quantitative, level.

  2. Investigation of spatial distribution of sound field parameters in ultrasound cleaning baths under the influence of cavitation.

    PubMed

    Jenderka, Klaus-Vitold; Koch, Christian

    2006-12-22

    Ultrasound cleaning baths fitting the full range from micromechanical components up to large machine parts, are regularly used in industry and in the lab. Despite the large number of applications, generally approved principles and objective criteria for parameter settings which allow an efficient operation are non-existent. The empirical selections of the running parameters often impede an optimization in terms of produce and reproducibility. One proposal for an objective description of the processes is the characterization of the sound field in the cleaning bath, which causes cavities, and subsequently, the cleaning process. Sound field measurements in the appropriate frequency range from 20kHz up to more then 1MHz incorporate a number of problems, such as large sensors disturbing the sound field, a lack of accuracy and the risk of being destroyed by cavitation bubbles. Measurement systems based on optical fiber tips and piezo-electrical hydrophones will be presented, which fulfil the accuracy requirements and withstand ultrasound fields with high power and cavitation. The spatial distribution of sound field parameters such as positive and negative peak pressure, amplitudes of fundamentals, harmonics and sub-harmonics as well as the energy density and spectral density in several frequency ranges are determined in experiments. Finally, the determined field parameters are related to the cavitation effects by means of photometric analysis of perforated aluminium foil. Perforations as well as intentions are analyzed and quantified from scanner images of the exposed foil samples using special image processing software. The experiments indicate clear differences in the structure of the sound fields and the spectral properties between the several types of cleaning baths, transducer arrangements and excitations. PMID:16781752

  3. Comment on `Energy transfer, entanglement and decoherence in a molecular dimer interacting with a phonon bath'

    E-print Network

    James Lim; Mark Tame; Ki Hyuk Yee; Joong-Sung Lee; Jinhyoung Lee

    2013-12-16

    We show that the influence of the shared phonon bath considered in H. Hossein-Nejad and G. D. Scholes, New J. Phys. 12, 065045 (2010) on the exciton transfer in a two-molecule system can be reproduced by that of an independent bath model.

  4. CURRENT AND EMERGING TECHNOLOGIES FOR EXTENDING THE LIFETIME OF ELECTROLESS NICKEL PLATING BATHS

    EPA Science Inventory

    The waste treatment and rejuvenation of spent electroless nickel baths has attracted a considerable amount of interest from electroplating shops, electroless nickel suppliers, universities and regulatory agencies due to the finite life of the baths and the associated waste that t...

  5. Rabi oscillations, decoherence, and disentanglement in a qubit-spin-bath system

    NASA Astrophysics Data System (ADS)

    Wu, Ning; Nanduri, Arun; Rabitz, Herschel

    2014-06-01

    We examine the influence of environmental interactions on simple quantum systems by obtaining the exact reduced dynamics of a qubit coupled to a one-dimensional spin bath. In contrast to previous studies, both the qubit-bath coupling and the nearest-neighbor intrabath couplings are taken as the spin-flip XX type. We first study the Rabi oscillations of a single qubit with the spin bath prepared in a spin coherent state, finding that nonresonance and finite intrabath interactions have significant effects on the qubit dynamics. Then we discuss the bath-induced decoherence of the qubit when the bath is initially in the ground state and show that the decoherence properties depend on the internal phases of the spin bath. By considering two independent copies of the qubit-bath system, we finally probe the disentanglement dynamics of two noninteracting entangled qubits. We find that entanglement sudden death appears when the spin bath is in its critical phase. We show that the single-qubit decoherence factor is an upper bound for the two-qubit concurrence.

  6. Copper Sulfate Foot Baths on Dairies and Crop Toxicities – What are the Risks?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A rising concern with the application of dairy wastes to agricultural fields is the accumulation of copper (Cu) in the soil. Copper sulfate (CuSO4) from cattle foot baths are washed out of dairy barns and into wastewater lagoons. The addition of CuSO4 baths has been reported to increase Cu concent...

  7. Two-level system in spin baths: Non-adiabatic dynamics and heat transport

    SciTech Connect

    Segal, Dvira [Chemical Physics Theory Group, Department of Chemistry, University of Toronto, 80 Saint George St., Toronto, Ontario M5S 3H6 (Canada)] [Chemical Physics Theory Group, Department of Chemistry, University of Toronto, 80 Saint George St., Toronto, Ontario M5S 3H6 (Canada)

    2014-04-28

    We study the non-adiabatic dynamics of a two-state subsystem in a bath of independent spins using the non-interacting blip approximation, and derive an exact analytic expression for the relevant memory kernel. We show that in the thermodynamic limit, when the subsystem-bath coupling is diluted (uniformly) over many (infinite) degrees of freedom, our expression reduces to known results, corresponding to the harmonic bath with an effective, temperature-dependent, spectral density function. We then proceed and study the heat current characteristics in the out-of-equilibrium spin-spin-bath model, with a two-state subsystem bridging two thermal spin-baths of different temperatures. We compare the behavior of this model to the case of a spin connecting boson baths, and demonstrate pronounced qualitative differences between the two models. Specifically, we focus on the development of the thermal diode effect, and show that the spin-spin-bath model cannot support it at weak (subsystem-bath) coupling, while in the intermediate-strong coupling regime its rectifying performance outplays the spin-boson model.

  8. Morphological and stoichiometric study of chemical bath deposited CdS films by varying ammonia concentration

    Microsoft Academic Search

    Q. Q. Liu; J. H. Shi; Z. Q. Li; D. W. Zhang; X. D. Li; Z. Sun; L. Y. Zhang; S. M. Huang

    2010-01-01

    The influence of ammonia concentration on stoichiometric, surface morphological, and optical properties of chemical bath deposited cadmium sulphide thin films has been studied systemically. Chemical bath deposition (CBD) of CdS thin films was carried out via using cadmium acetate as the cadmium ion source, thiourea as the sulphur source and ammonia as the complexing agent. Ammonia concentration was changed from

  9. Physical properties of chemical bath deposited CdS thin films

    Microsoft Academic Search

    J. N. Ximello-Quiebras; G. Contreras-Puente; J. Aguilar-Hernández; G. Santana-Rodriguez; A. Arias-Carbajal Readigos

    2004-01-01

    Cadmium sulfide films of different thicknesses were deposited by chemical bath deposition (CBD) from a bath containing cadmium chloride, ammonium chloride, ammonium hydroxide and thiourea. The XRD patterns show that the films have a hexagonal phase with a preferential (002) orientation. The photoluminescence spectra show a defect structure, characteristics of the CdS films obtained by CBD. The electrical behavior in

  10. Ergodicity of the Stochastic NoseHoover Heat Bath Wei Chung LO

    E-print Network

    Li, Baowen

    of the important issues in studying many nonequilibrium processes. Specifi- cally, the appropriate modeling of the interactions between any systems of interest and heat bath is of great importance for the investigation of a system with heat bath, which resembles infinite degrees of freedom. However, in stark contrast

  11. Weakly coupled heat bath models for Gibbs-like invariant states in nonlinear wave equations

    E-print Network

    Frank, Jason

    Weakly coupled heat bath models for Gibbs-like invariant states in nonlinear wave equations J the ergodicity of approaches based on coupling of the heat bath to the high wave numbers, with the goal is that convergence to the invariant distribution can be achieved by thermostatting just the highest wave number

  12. Structural, morphological and optical properties of cadmium sulphide thin films grown using chemical bath deposition technique

    NASA Astrophysics Data System (ADS)

    Shah, N. M.

    2013-06-01

    Cadmium sulphide (CdS) thin films were deposited onto glass substrates by the chemical bath deposition (CBD) technique. Aqueous baths of cadmium sulphate and thiourea were used as sources of cadmium (Cd+2) and sulphur (S-2) ions, respectively. The influence of the varied bath temperature from 65°C to 85°C in a step of 10°C on the crystallographic structure, morphology as well as optical properties of as-deposited films were investigated in detail. Increasing bath temperature can promote phase transformation from cubic to hexagonal and improvement of crystallinity in CdS films. CdS film deposited at 85° C shows compact and smooth surface, and excellent transmission in visible light range. The band gaps are found to decrease from 2.52 eV to 2.36 eV with the increase of bath temperature.

  13. WORKSHOP ON ORGANIZATION AND OPERATION OF COOPERATIVE WORK EXPERIENCE PROGRAMS IN TRADE AND INDUSTRIAL EDUCATION. (TUSKEGEE INSTITUTE, AUGUST 14-SEPTEMBER 1, 1967). FINAL REPORT.

    ERIC Educational Resources Information Center

    HARRIS, JAMES N.; SHERARD, AUSTELL O.

    THIRTY-NINE TRADE AND INDUSTRIAL AND VOCATIONAL TECHNICAL TEACHERS AND SUPERVISORS FROM 19 STATES PARTICIPATED IN A WORKSHOP TO PLAN AND EXECUTE A COMPREHENSIVE EXAMINATION AND EVALUATION OF THE COOPERATIVE WORK EXPERIENCE PLAN OF EDUCATION RELATIVE TO TRADE AND INDUSTRIAL EDUCATION. THE WORKSHOP ORGANIZATION INCLUDED CONSULTANT PRESENTATIONS,…

  14. Quality, Evolution, and Positional Change of University Students' Argumentation Patterns about Organic Agriculture during an Argument-Critique-Argument Experience

    ERIC Educational Resources Information Center

    Yu, Shu-Mey; Yore, Larry D.

    2013-01-01

    The purpose of this study was to investigate the quality, evolution, and position of university students' argumentation about organic agriculture over a 4-week argument-critique-argument e-learning experience embedded in a first year university biology course. The participants (N = 43) were classified into three groups based on their…

  15. Detection of Salicylic Acid in Willow Bark: An Addition to a Classic Series of Experiments in the Introductory Organic Chemistry Laboratory

    ERIC Educational Resources Information Center

    Clay, Matthew D.; McLeod, Eric J.

    2012-01-01

    Salicylic acid and its derivative, acetylsalicylic acid, are often encountered in introductory organic chemistry experiments, and mention is often made that salicylic acid was originally isolated from the bark of the willow tree. This biological connection, however, is typically not further pursued, leaving students with an impression that biology…

  16. Effects of organic amendments on soil carbon content and microbial biomass – results of the long-term box plot experiment in Grossbeeren

    Microsoft Academic Search

    Jörg Rühlmann; Silke Ruppel

    2005-01-01

    The Box Plot Experiment in Grossbeeren was set up in 1972 to investigate diverse fertilization strategies within an irrigated vegetable crop rotation system for three different soils. Here we report on the long-term effects of applying different organic amendments and mineral N fertilizer levels to soils on the content of: (1) microbially decomposable carbon (Cdec); and (2) microbial biomass carbon

  17. Analysis And Control Of Copper Plating Bath Additives And By-Products

    NASA Astrophysics Data System (ADS)

    Newton, Beverly; Kaiser, Edward

    2003-09-01

    New copper plating bath chemisties are being developed to meet the emerging need of plating copper into submicron features on semiconductor wafers. These chemistries are designed to provide a fast, efficient, fill for even the most challenging wafer terrain. It has been found that maintaining the concentration of the additives in these plating baths at certain levels is critical to the performance of the bath. Plating technology for semiconductor applications requires rigid bath control and disciplined methodology. Establishing correlations between what is found in the plated film and bath chemistry control parameters is fundamental in producing interconnects that are consistent and reliable. To establish these correlations, it is important to have a clear understanding of the chemical composition of the bath. It is theorized that the "suppressor" bath components help moderate the deposition rate of the copper fill and the "leveler" additives improve the topology of the copper overfill. Too much or too little of these components in the bath can be detrimental to the quality of the copper deposition and may result in "fill failure" leading to a higher than necessary scrap rate for the wafers. Indirect bath measurements, such as Cyclic Voltammetric Stripping (CVS), tell an incomplete story as these techniques only measures the combined effect of the additives and by-products on the plating quality. High Performance Liquid (HPLC) and Ion Chromatography are analytical techniques which provide important information on the concentration, chemical balance and trend measurement of major constituents such as additives, brighteners, boosters, stabilizers, carriers, levelers, inhibitors, accelerators, transition metals, metal complexes and contaminants in the plating bath. This information provides for improved device quality, reduced scrap rate and reduced costs of bath maintenance. This, however, is not the end of the story. In addition to additives, copper plating baths also contain process byproducts. This paper will cover the development of analytical methods using metal free liquid chromatography to quantify the components and any related by-products found in copper plating baths used for small-featured semiconductors..

  18. Organic matter production response to CO2 increase in open subarctic plankton communities: Comparison of six microcosm experiments under iron-limited and -enriched bloom conditions

    NASA Astrophysics Data System (ADS)

    Yoshimura, Takeshi; Sugie, Koji; Endo, Hisashi; Suzuki, Koji; Nishioka, Jun; Ono, Tsuneo

    2014-12-01

    Increase in seawater pCO2 and the corresponding decrease in pH caused by the increasing atmospheric CO2 concentration (i.e., ocean acidification) may affect organic matter production by phytoplankton communities. Organic matter production forms the basis of marine food webs and plays a crucial role in oceanic CO2 uptake through the biological carbon pump, and hence will potentially affect future marine ecosystem dynamics. However, responses of organic matter production in open ocean plankton ecosystems to CO2 increase have not been fully examined. We conducted on-deck microcosm experiments using high nutrient, low chlorophyll (HNLC) waters in the western subarctic Pacific and oceanic Bering Sea basin in summer 2008 and 2009, respectively, to examine the impacts of elevated CO2 on particulate and dissolved organic matter (i.e., POM and DOM, respectively) production. Iron deficient natural plankton communities were incubated for 7-14 days under multiple CO2 levels with and without iron enrichments (hereafter +Fe and -Fe treatments, respectively). By combining with our previous experiments at two sites, we created a comprehensive dataset on responses of organic matter production to CO2 increase during macronutrient replete conditions in HNLC waters. Significant differences in net particulate organic carbon production among CO2 treatments were observed only in the -Fe treatments, whereas that in net dissolved organic carbon production were mainly observed in the +Fe treatments, suggesting that CO2 may affect different processes depending on the Fe nutritional status. However, impacts of CO2 were not consistent among experiments and were much smaller than the consistent positive effects of Fe enrichment. In contrast, no significant differences among the CO2 treatments were observed for organic carbon partitioning into POM and DOM, and carbon to nitrogen ratio of net produced POM. We conclude that CO2 does not play a primary role, but could have secondary effects on controlling the organic matter production under macronutrient replete conditions in HNLC waters. On the other hand, in a nutrient-depleted, declining phase of the phytoplankton bloom induced by Fe enrichment, carbon overconsumption was found in an experiment with elevated CO2 conditions suggesting that CO2 impacts might become more significant in such environments.

  19. The chemical/physical and microbiological characteristics of typical bath and laundry waste waters. [waste water reclamation during manned space flight

    NASA Technical Reports Server (NTRS)

    Hypes, W. D.; Batten, C. E.; Wilkins, J. R.

    1974-01-01

    Chemical/physical and microbiological characteristics are studied of typical bath and laundry waters collected during a 12 day test in which the untreated waste waters were reused for toilet flush. Most significant changes were found for ammonia, color, methylene blue active substances, phosphates, sodium, sulfates, total organic carbon, total solids, and turbidity in comparison with tap water baseline. The mean total number of microorganisms detected in the waste waters ranged from 1 million to 10 to the 7th power cells/m1 and the mean number of possible coliforms ranged from 10 to the 5th power to 1 million. An accumulation of particulates and an objectible odor were detected in the tankage used during the 12 day reuse of the untreated waste waters. The combined bath and laundry waste waters from a family of four provided 91 percent of the toilet flush water for the same family.

  20. Bath's Law as a Consequence of Magnitude Distribution

    NASA Astrophysics Data System (ADS)

    Console, R.; Maura, M.; Lombardi, A.

    2002-12-01

    We revisit the issue of the so-called Bath's law concerning the difference D1 between the magnitude of the mainshock, M0, and the second largest shock, M1, in the same sequence. Various authors, in the past, observed that this difference is approximately equal to 1.2. Feller demonstrated in 1966 that the D1 expected value was about 0.5 given that the difference between the two largest random variables of a sample, N, exponentially distributed is also a random variable with the same distribution. Feller's proof leads to the consequence that the mainshock comes from a sample, which is different from the one of its aftershocks. A mathematical formulation of the problem is developed here, the only assumption being that all the events belong to the same self-similar set of earthquakes following the Gutenberg-Richter magnitude distribution with a constant b-value. Assuming that the number of aftershocks in each aftershock series is known, and not extremely large, this model shows a substantial dependence of D1 on the magnitude thresholds chosen for the mainshock and its largest aftershock. In this way it explains the large D1 values reported in the past. Analysis of the PDE catalog of shallow earthquakes demonstrates a good agreement between the average D1 values predicted by the theoretical model and those observed. Limiting our attention to the average D1 values, Bath's law doesn't seem to strongly contradict the Gutenberg-Richter law. Nevertheless, a detailed analysis of the observed D1 distribution shows that the Gutenberg-Richter hypothesis doesn't fully explain the experimental observations. The theoretical distribution has a larger proportion of low D1 values and a smaller proportion of high D1 values than the experimental observations. A reasonable explanation for this mismatch, which appears a minor effect with respect to what was supposed in the past, seems to consist in the byes (not assumed in the model) that the selection of clustered events produces on the average b-value.

  1. Laser-induced breakdown spectroscopy at a water/gas interface: A study of bath gas-dependent molecular species

    NASA Astrophysics Data System (ADS)

    Adamson, M.; Padmanabhan, A.; Godfrey, G. J.; Rehse, S. J.

    2007-12-01

    Single-pulse laser-induced breakdown spectroscopy has been performed on the surface of a bulk water sample in an air, argon, and nitrogen gas environment to investigate emissions from hydrogen-containing molecules. A microplasma was formed at the gas/liquid interface by focusing a Nd:YAG laser beam operating at 1064 nm onto the surface of an ultra-pure water sample. A broadband Echelle spectrometer with a time-gated intensified charge-coupled device was used to analyze the plasma at various delay times (1.0-40.0 ?s) and for incident laser pulse energies ranging from 20-200 mJ. In this configuration, the dominant atomic spectral features at short delay times are the hydrogen H-alpha and H-beta emission lines at 656 and 486 nm, respectively, as well as emissions from atomic oxygen liberated from the water and air and nitrogen emission lines from the air bath gas. For delay times exceeding approximately 8 ?s the emission from molecular species (particularly OH and NH) created after the ablation process dominates the spectrum. Molecular emissions are found to be much less sensitive to variations in pulse energy and exhibit a temporal decay an order of magnitude slower than the atomic emission. The dependence of both atomic hydrogen and OH emission on the bath gas above the surface of the water was studied by performing the experiment at standard pressure in an atmospheric purge box. Electron densities calculated from the Stark broadening of the H-beta and H-gamma lines and plasma excitation temperatures calculated from the ratio of H-beta to H-gamma emission were measured for ablation in the three bath gases.

  2. Influence of a compost layer on the attenuation of 28 selected organic micropollutants under realistic soil aquifer treatment conditions: Insights from a large scale column experiment.

    PubMed

    Schaffer, Mario; Kröger, Kerrin Franziska; Nödler, Karsten; Ayora, Carlos; Carrera, Jesús; Hernández, Marta; Licha, Tobias

    2015-05-01

    Soil aquifer treatment is widely applied to improve the quality of treated wastewater in its reuse as alternative source of water. To gain a deeper understanding of the fate of thereby introduced organic micropollutants, the attenuation of 28 compounds was investigated in column experiments using two large scale column systems in duplicate. The influence of increasing proportions of solid organic matter (0.04% vs. 0.17%) and decreasing redox potentials (denitrification vs. iron reduction) was studied by introducing a layer of compost. Secondary effluent from a wastewater treatment plant was used as water matrix for simulating soil aquifer treatment. For neutral and anionic compounds, sorption generally increases with the compound hydrophobicity and the solid organic matter in the column system. Organic cations showed the highest attenuation. Among them, breakthroughs were only registered for the cationic beta-blockers atenolol and metoprolol. An enhanced degradation in the columns with organic infiltration layer was observed for the majority of the compounds, suggesting an improved degradation for higher levels of biodegradable dissolved organic carbon. Solely the degradation of sulfamethoxazole could clearly be attributed to redox effects (when reaching iron reducing conditions). The study provides valuable insights into the attenuation potential for a wide spectrum of organic micropollutants under realistic soil aquifer treatment conditions. Furthermore, the introduction of the compost layer generally showed positive effects on the removal of compounds preferentially degraded under reducing conditions and also increases the residence times in the soil aquifer treatment system via sorption. PMID:25723339

  3. 33 CFR 334.782 - SUPSHIP Bath Maine Detachment Mobile at AUSTAL, USA, Mobile, AL; restricted area.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 2010-07-01 false SUPSHIP Bath Maine Detachment Mobile at AUSTAL, USA, Mobile...REGULATIONS § 334.782 SUPSHIP Bath Maine Detachment Mobile at AUSTAL, USA, Mobile...Shipbuilding, Conversion and Repair, USN, Bath, Maine or his/her authorized...

  4. Characterization of CdS thin films grown by chemical bath deposition using four different cadmium sources

    E-print Network

    Chow, Lee

    Characterization of CdS thin films grown by chemical bath deposition using four different cadmium in the deposition of CdS, chemical bath deposition is known to enhance the performance of cadmium sulfide window January 2008 Abstract A comprehensive study of the effect of cadmium sources on chemical bath deposited

  5. Optimization of chemical bath deposited CdS thin films using nitrilotriacetic acid as a complexing agent

    E-print Network

    Chow, Lee

    Optimization of chemical bath deposited CdS thin films using nitrilotriacetic acid as a complexing; Thin films; Chemical bath deposition; Nitrilotriacetic acid 1. Introduction Cadmium sulfide (CdS), due deposition was used to grow the CdS window [29,30]. Chemical bath deposition is the analog in liquid phase

  6. Characterization of gallium-doped CdS thin films grown by chemical bath Hani Khallaf a

    E-print Network

    Chow, Lee

    Characterization of gallium-doped CdS thin films grown by chemical bath deposition Hani Khallaf using chemical bath deposition. The effect of Ga-doping on optical properties and bandgap of CdS films bath deposition A B S T R A C T Ga-doped CdS thin films, with different [Ga]/[Cd] ratios, were grown

  7. Centre for Sustainable Chemical Technologies Summer Showcase; 16 -18 Sept 2013 Monday 16 Sept; East Building, University of Bath

    E-print Network

    Burton, Geoffrey R.

    ; East Building, University of Bath 12:00-13:00 Welcome Lunch and Posters Chair: 13:00-13:10 Opening 13-free Biorefineries and Fine Chemicals 13:50-14:05 David McClymont, DTC in SCT PhD student, University of Bath Novel Frank Marken, University of Bath Sand-Sea-Sunlight: Energy Harvesting at the Triple Phase Boundary 14

  8. Mechanisms of carrier transport induced by a microswimmer bath

    E-print Network

    Andreas Kaiser; Andrey Sokolov; Igor S. Aranson; Hartmut Löwen

    2014-08-08

    Recently, it was found that a wedgelike microparticle (referred to as "carrier") which is only allowed to translate but not to rotate exhibits a directed translational motion along the wedge cusp if it is exposed to a bath of microswimmers. Here we model this effect in detail by resolving the microswimmers explicitly using interaction models with different degrees of mutual alignment. Using computer simulations we study the impact of these interactions on the transport efficiency of V-shaped carrier. We show that the transport mechanisms itself strongly depends on the degree of alignment embodied in the modelling of the individual swimmer dynamics. For weak alignment, optimal carrier transport occurs in the turbulent microswimmer state and is induced by swirl depletion inside the carrier. For strong aligning interactions, optimal transport occurs already in the dilute regime and is mediated by a polar cloud of swimmers in the carrier wake pushing the wedge-particle forward. We also demonstrate that the optimal shape of the carrier leading to maximal transport speed depends on the kind of interaction model used.

  9. Heat current characteristics in nanojunctions with superconducting baths

    NASA Astrophysics Data System (ADS)

    Oettinger, David; Chitra, R.; Restrepo, Juliana

    2014-10-01

    As a fundamental requisite for thermotronics, controlling heat flow has been a longstanding quest in solid state physics. Recently, there has been a lot of interest in nanoscale hybrid systems as possible candidates for thermal devices. In this context, we study the heat current in the simplest hybrid device of a two level system weakly coupled to two heat baths. We use the reduced density matrix approach together with a simple Born-Markov approximation to calculate the heat current in the steady state. We consider different kinds of reservoirs and show that the nature of the reservoir plays a very important role in determining the thermal characteristics of the device. In particular, we investigate the effectiveness of a conventional superconductor as a reservoir with regard to manipulating the heat current. In the emergent temperature characteristics, we find that superconductivity in the reservoirs leads to enhanced thermal currents and that the superconducting phase transition is clearly visible in the heat current. We observe negative differential thermal conductance and a pronounced rectification of the heat current, making this a good building block for a quantum thermal diode.

  10. NATURAL GRADIENT EXPERIMENT ON SOLUTE TRANSPORT IN A SAND AQUIFER. 3. RETARDATION ESTIMATES AND MASS BALANCES FOR ORGANIC SOLUTES

    EPA Science Inventory

    The long-term behavior of five organic solutes during transport over a period of 2 years in ground water under natural gradient conditions was characterized quantitatively by means of moment estimates. Total mass was conserved for two of the organic compounds, carbon tetrachlorid...

  11. Preparation, Characterization, and Postsynthetic Modification of Metal-Organic Frameworks: Synthetic Experiments for an Undergraduate Laboratory Course in Inorganic Chemistry

    ERIC Educational Resources Information Center

    Sumida, Kenji; Arnold, John

    2011-01-01

    Metal-organic frameworks (MOFs) are crystalline materials that are composed of an infinite array of metal nodes (single ions or clusters) linked to one another by polyfunctional organic compounds. Because of their extraordinary surface areas and high degree of control over the physical and chemical properties, these materials have received much…

  12. Looking inside the Black Box: The Value Added by Career and Technical Student Organizations to Students' High School Experience

    ERIC Educational Resources Information Center

    Alfeld, Corinne; Stone, James R., III; Aragon, Steven R.; Hansen, David M.; Zirkle, Christopher; Connors, James; Spindler, Matt; Romine, Rebecca Swinburne; Woo, Hui-Jeong

    2007-01-01

    In addition to hands-on learning in classrooms and work-related activities such as co-op, many CTE programs offer a career-focused student organization, known as a Career and Technical Student Organization, or CTSO. CTSOs have been touted as developing such characteristics as leadership and employability skills in students; however, there is…

  13. Sampling from living organisms: section 3 in Sampling and experiments with biofilms in the environment: chapter 6

    USGS Publications Warehouse

    Kellogg, Christina A.

    2014-01-01

    Living organisms, unlike inanimate surfaces, seem to exert some control over their surface microbiota, in many cases maintaining conserved, species-specific microbial communities. Microbial ecologists seek to characterize and identify these microbes to understand the roles they are playing in the larger organism's biology.

  14. Identification of significant transport processes for organic micropollutant classes during soil aquifer treatment (SAT) - a controlled field experiment

    Microsoft Academic Search

    Karsten Nödler; Tobias Licha; Martin Sauter

    2010-01-01

    Supplementing existing water resources with alternative sources of water is a challenge in semi-arid areas, as deterioration of water quality must be avoided. Soil aquifer treatment (SAT) can greatly improve the quality of the injected water by attenuation of organic pollutants via sorption and degradation processes. However, only little is known about the specific transport processes of organic micropollutants under

  15. Noncanonical statistics of a finite quantum system with non-negligible system-bath coupling

    NASA Astrophysics Data System (ADS)

    Xu, D. Z.; Li, Sheng-Wen; Liu, X. F.; Sun, C. P.

    2014-12-01

    The canonical statistics describes the statistical properties of an open system by assuming its coupling with the heat bath is infinitesimal in comparison with the total energy in thermodynamic limit. In this paper, we generally derive a noncanonical density matrix for the open system with a finite coupling to the heat bath, which deforms the energy shell to effectively modify the conventional canonical way. The obtained noncanonical distribution reflects the back action of system on the bath and thus depicts the statistical correlations between two subsystems by the mutual information as a result of energy conservation.

  16. Hypercalcemic crisis resulting from near drowning in an indoor public bath

    PubMed Central

    Matsumoto, Ryusaku; Yamada, Go; Amano, Aya; Yamada, Tomoko; Hamamatsu, Keita; Murabe, Hiroyuki; Yokota, Toshihiko

    2013-01-01

    Patient: Male, 66 Final Diagnosis: Hypercalcemic crisis Symptoms: Near drowning state Medication: — Clinical Procedure: — Specialty: Critical care medicine Objective: Challenging differential diagnosis Background: Hypercalcemic crisis, generally caused by malignancy or primary hyperparathyroidism, is a life-threatening emergency that can result in multi-organ failure. Lowering the patient’s calcium level immediately and determining the correct etiology are essential. Case Report: We report a case of hypercalcemic crisis with a novel etiology. A 66-year-old male presented to the emergency room in cardiac arrest with a ventricular arrhythmia after being discovered submerged in an indoor public bath. He underwent cardioversion and was emergently intubated. Computed tomography showed bilateral pulmonary edema, suspected from water aspiration. Laboratory data revealed severe hypercalcemia and mild hypernatremia. Following three days of continuous hemodiafiltration, serum Ca decreased to and remained within normal limits. We concluded the etiology of hypercalcemia was absorption of Ca resulting from aspirated water. Conclusions: Near drowning can be a cause of hypercalcemic crisis. For cases of near drowning, it is important to investigate the source of the aspirated water and consider electrolyte abnormalities in the diagnosis. PMID:23826470

  17. Seasonal evolution of beach waste and litter during the bathing season on the Catalan coast.

    PubMed

    Ariza, Eduard; Jiménez, José A; Sardá, Rafael

    2008-12-01

    Beach waste and litter composition and evolution on popular urban (located in the main nucleus of the municipality) and urbanized (located in residential areas outside the main nucleus) beaches of the Costa Brava (Catalan coast) were assessed during the bathing season. Waste and litter production (amount and composition) were affected by urbanization and varied during the summer. Urban beaches had higher densities of waste deposition and lower percentages of organic, domestic and other miscellaneous waste than urbanized beaches. Litter characteristics were also influenced by type of beach, and varied during the season as a consequence of beach use and cleaning practices, but not environmental factors. Urbanized beaches obtained higher scores for aesthetic quality of sand than urban beaches, and small-sized litter tended to accumulate during the season in the beach of Lloret Centre. The most important problems are management of recyclable materials, litter left by users on the sand, and separation of sand from litter. In addition, current efficiency of mechanical cleaning is low, especially in the withdrawal of cigarette butts. These analyses highlight problems that should be addressed in future management of area beaches. PMID:18243682

  18. Are Organic Falls Bridging Reduced Environments in the Deep Sea? - Results from Colonization Experiments in the Gulf of Cádiz

    PubMed Central

    Cunha, Marina R.; Matos, Fábio L.; Génio, Luciana; Hilário, Ana; Moura, Carlos J.; Ravara, Ascensão; Rodrigues, Clara F.

    2013-01-01

    Organic falls create localised patches of organic enrichment and disturbance where enhanced degradation is mediated by diversified microbial assemblages and specialized fauna. The view of organic falls as “stepping stones” for the colonization of deep-sea reducing environments has been often loosely used, but much remains to be proven concerning their capability to bridge dispersal among such environments. Aiming the clarification of this issue, we used an experimental approach to answer the following questions: Are relatively small organic falls in the deep sea capable of sustaining taxonomically and trophically diverse assemblages over demographically relevant temporal scales? Are there important depth- or site-related sources of variability for the composition and structure of these assemblages? Is the proximity of other reducing environments influential for their colonization? We analysed the taxonomical and trophic diversity patterns and partitioning (?- and ?-diversity) of the macrofaunal assemblages recruited in small colonization devices with organic and inorganic substrata after 1-2 years of deployment on mud volcanoes of the Gulf of Cádiz. Our results show that small organic falls can sustain highly diverse and trophically coherent assemblages for time periods allowing growth to reproductive maturity, and successive generations of dominant species. The composition and structure of the assemblages showed variability consistent with their biogeographic and bathymetric contexts. However, the proximity of cold seeps had limited influence on the similarity between the assemblages of these two habitats and organic falls sustained a distinctive fauna with dominant substrate-specific taxa. We conclude that it is unlikely that small organic falls may regularly ensure population connectivity among cold seeps and vents. They may be a recurrent source of evolutionary candidates for the colonization of such ecosystems. However, there may be a critical size of organic fall to create the necessary intense and persistent reducing conditions for sustaining typical chemosymbiotic vent and seep organisms. PMID:24098550

  19. Are organic falls bridging reduced environments in the deep sea? - results from colonization experiments in the Gulf of Cádiz.

    PubMed

    Cunha, Marina R; Matos, Fábio L; Génio, Luciana; Hilário, Ana; Moura, Carlos J; Ravara, Ascensão; Rodrigues, Clara F

    2013-01-01

    Organic falls create localised patches of organic enrichment and disturbance where enhanced degradation is mediated by diversified microbial assemblages and specialized fauna. The view of organic falls as "stepping stones" for the colonization of deep-sea reducing environments has been often loosely used, but much remains to be proven concerning their capability to bridge dispersal among such environments. Aiming the clarification of this issue, we used an experimental approach to answer the following questions: Are relatively small organic falls in the deep sea capable of sustaining taxonomically and trophically diverse assemblages over demographically relevant temporal scales? Are there important depth- or site-related sources of variability for the composition and structure of these assemblages? Is the proximity of other reducing environments influential for their colonization? We analysed the taxonomical and trophic diversity patterns and partitioning (?- and ?-diversity) of the macrofaunal assemblages recruited in small colonization devices with organic and inorganic substrata after 1-2 years of deployment on mud volcanoes of the Gulf of Cádiz. Our results show that small organic falls can sustain highly diverse and trophically coherent assemblages for time periods allowing growth to reproductive maturity, and successive generations of dominant species. The composition and structure of the assemblages showed variability consistent with their biogeographic and bathymetric contexts. However, the proximity of cold seeps had limited influence on the similarity between the assemblages of these two habitats and organic falls sustained a distinctive fauna with dominant substrate-specific taxa. We conclude that it is unlikely that small organic falls may regularly ensure population connectivity among cold seeps and vents. They may be a recurrent source of evolutionary candidates for the colonization of such ecosystems. However, there may be a critical size of organic fall to create the necessary intense and persistent reducing conditions for sustaining typical chemosymbiotic vent and seep organisms. PMID:24098550

  20. Analysis Of Organic Molecules On Mars With The Gas Chromatograph Mass Spectrometer Of The SAM Experiment Of The MSL 2011 Mission

    NASA Astrophysics Data System (ADS)

    Szopa, C.; Coll, P. J.; Cabane, M.; Noblet, A.; Buch, A.; Freissinet, C.; Mahaffy, P. R.; Eigenbrode, J. L.; Glavin, D. P.; Francois, P.; Stalport, F.

    2011-12-01

    The search for organic molecules at the Mars surface is of primary importance to evaluate the possibility for a prebiotic chemistry to have occurred on Mars, and also to determine the influence of the surface environmental conditions on the organic materials. In the frame of the NASA's MSL2011 mission, the Gas Chromatograph Quadrupole Mass Spectrometer (GC-QMS) of the Sample Analysis at Mars experiment (SAM) will be the main instrumentation to seek for organics. It will indeed analyse either atmospheric gases, or the gaseous products released by soils or rocks samples submitted to thermal or chemical treatments in the Sampling and Manipulation System of SAM. To reach that goal, the GC, dedicated to separate gaseous species, is composed of six different analytical channels, each one devoted to a specific range of chemical compounds. This configuration enables for the separation of a broad range of chemical species, from permanent gases to organic molecules containing up to 20 carbon atoms approximately, as well as enantiomers. The QMS provides structural information on the molecules analysed with the GC, enabling their identification which is the primary objective concerning the organics. This paper will present a view of the analytical capabilities of the GC-QMS used in SAM, with a focus on the GC part. Based on results obtained with laboratory tests performed during the development of the GC, and also on tests performed with the engineering and flight models of the GC and QMS coupled together, we will present a view of the analytical capabilities for the experiment to detect and identify a broad range of organics, including large molecules of astrobiological interest and chiral organics.

  1. Building capacity for HIV/AIDS prevention among Asian Pacific Islander organizations: the experience of a culturally appropriate capacity-building program in Southern California.

    PubMed

    Takahashi, Lois M; Candelario, Jury; Young, Tim; Mediano, Elizabeth

    2007-01-01

    This article has two goals: (1) to outline a conceptual model for culturally appropriate HIV prevention capacity building; (2) to present the experiences from a 3-year program provided by Asian Pacific AIDS Intervention Team to Asian Pacific Islander (API) organizations in southern California. The participating organizations were of two types: lesbian, gay, bisexual, transgender, and questioning (LGBTQ) social organizations and social service agencies not targeting LGBTQ. These organizations were selected for participation because of their commitment to HIV/AIDS issues in API communities. An organizational survey and staff observations were used to explore changes in capacity. The organizations were mostly small, targeted diverse populations, served a large geographic area (southern California as a region), and were knowledgeable about HIV. Organizations became more viable (more capacity in human resources, financial, external relations, and strategic management), but also more unstable (large growth in paid staff and board members), and showed more capacity in HIV knowledge environments (especially less stigma and more sensitivity to diverse populations). The results suggest that capacity can expand over a short period of time, but as capacity increases, organizational viability/stability and HIV knowledge environments change, meaning that different types of technical assistance would be needed for sustainability. PMID:17159469

  2. Habitual hot-spring bathing by a group of Japanese macaques (Macaca fuscata) in their natural habitat.

    PubMed

    Zhang, Peng; Watanabe, Kunio; Eishi, Tokida

    2007-12-01

    Japanese macaques (Macaca fuscata) in a free-ranging group in Jigokudani valley, Nagano prefecture, are known to bathe in a hot spring. We used scan sampling in a study aimed at elucidating the causal factors and possible social transmission of this behavior. From 1980-2003, 31% of a total 114 females in the group habitually bathed in the hot spring. The habit was more widespread in dominant matrilines than in subordinate matrilines. Infants whose mothers bathed were more likely to bathe than infants of mothers who did not bathe. The number of monkeys bathing was clearly influenced by ambient air temperature. More monkeys bathed in the hot spring in winter than in summer. The results support the thermoregulation hypothesis of hot-spring bathing. Bathing behavior varies among age and sex categories of monkeys, with adult females and juveniles bathing more often than adult males and subadults. We compared hot-spring bathing with other thermoregulatory behaviors in various primate populations. PMID:17554750

  3. [Experience in organization of joint actions of expert divisions during the accident at P.S. Podporozniy Sayano-Shushenskaya hydroelectric power station].

    PubMed

    Kolkutin, V V; Ivanov, P L; Fetisov, V A; Afanas'ev, S A; Dorozhkin, O A; Vognerubov, R N; Kuznetsov, T L

    2010-01-01

    The authors illustrate positive experience in organization and coordination of joint actions of expert divisions of different sectors during the accident at P.S. Podporozniy Sayano-Shushenskaya hydroelectric power station in August 2009. Special emphasis is laid on the participation of experts of quick-reaction teams formed by territorial forensic medical bureaus, mobile and supporting forces from the adjacent regions. PMID:20560514

  4. Flashback phenomenon and residual neurological deficits after the use of “bath salt” 3, 4- methylenedioxypyrovalerone

    PubMed Central

    Mangold, Aaron R.; Bravo, Thomas P; Traub, Stephen J.; Maher, Steven A.; Lipinski, Christopher A.

    2014-01-01

    BACKGROUND: The use and abuse of designer drugs has been recognized for decades; however there are many derivatives of compounds that make their way into the community. Abuse of compound(s) known on the street as “bath salt” is on the rise. METHODS: We report the case of a 33-year-old man who complained of “flashbacks” and right arm shaking that followed a night of “bath salt” snorting. The active compound methylenedioxypyrovalerone methamphetamine (MDPV) was confirmed; however, analysis of three different “bath salt” products showed difference in their active components. RESULTS: The patient's symptoms remained stable and he was discharged home after observation in the emergency department with instructions to return for any symptom progression. CONCLUSION: Practitioners should be aware of the abuse of the compounds and that not all “bath salt” products contain MDPV. PMID:25215150

  5. Surface modification of 2205 duplex stainless steel by low temperature salt bath nitrocarburizing at 430 °C

    NASA Astrophysics Data System (ADS)

    Huang, Runbo; Wang, Jun; Zhong, Si; Li, Mingxing; Xiong, Ji; Fan, Hongyuan

    2013-04-01

    2205 stainless steel was modified by salt bath nitrocarburizing at 430 °C in this study. The microstructure, surface hardness and erosion-corrosion resistance were systematically evaluated. Salt bath nitrocarburizing at 430 °C can form a nitrocarburized layer, and with the treated time prolong, the thickness of the layer increased. By nitrocarburizing within 8 h, only expanded austenite (S phase) formed. With treated time increased, CrN gradually diffused from the places where there were ferrite grains in the layer before nitrocarburizing. Besides, the depth increased with the nitrocarburized time and the layer grew approximately conforms to the parabolic rate law. Salt bath nitrocarburizing can effectively improve the surface hardness of 2205 DSS. The erosion-corrosion resistance was improved by salt bath nitrocarburizing and the 16 h treated sample had the best erosion-corrosion behavior.

  6. Entanglement of a 2-qubit system coupled to a bath of quantum spin glass

    NASA Astrophysics Data System (ADS)

    Koh, C. Y.; Kwek, L. C.

    2014-06-01

    We study the quantum entanglement (concurrence) of a 2-qubit system coupled to a small spin glass bath of 2 to n? 4 qubits. The bath is described by the quantum XX Heisenberg model with random J coupling and varying magnetic field h. We look at the dynamics of the steady state average concurrence for the system and obtain a general formula to describe the concurrence with J=0 and h=0 for n bath sites. The physics of 2-qubit system coupled with n bath sites for J=0 is analytically described for small n. The result for large n was numerically found to be qualitatively similar. For small fluctuation in J, a mean steady state average concurrence of about 0.5 is obtained.

  7. Hyperfine induced electron spin and entanglement dynamics in double quantum dots: The case of separate baths

    NASA Astrophysics Data System (ADS)

    Erbe, B.; Schliemann, J.

    2012-04-01

    We consider a system of two strongly coupled electron spins in zero magnetic field, each of which is interacting with an individual bath of nuclear spins via the hyperfine interaction. Applying the long-spin approximation that we introduced in a previous paper [Europhys. Lett.EULEEJ0295-507510.1209/0295-5075/95/47009 95, 47009 (2011)] (here each bath is replaced by a single long spin), we numerically study the electron spin and entanglement dynamics. We demonstrate that the decoherence time is scaling with the bath size according to a power law. As expected, the decaying part of the dynamics decreases with increasing bath polarization. However, surprisingly it turns out that, under certain circumstances, combining quantum dots of different geometry to the double dot setup has a very similar effect on the magnitude of the spin decay. Finally, we show that even for a comparatively weak exchange coupling the electron spins can be fully entangled.

  8. Directed motion generated by heat bath nonlinearly driven by external noise

    NASA Astrophysics Data System (ADS)

    Chaudhuri, J. Ray; Barik, D.; Banik, S. K.

    2007-12-01

    Based on the heat bath system approach where the bath is nonlinearly modulated by an external Gaussian random force, we propose a new microscopic model to study directed motion in the overdamped limit for a nonequilibrium open system. Making use of the coupling between the heat bath and the external modulation as a small perturbation, we construct a Langevin equation with multiplicative noise- and space-dependent dissipation and the corresponding Fokker-Planck-Smoluchowski equation in the overdamped limit. We examine the thermodynamic consistency condition and explore the possibility of observing a phase-induced current as a consequence of state-dependent diffusion and, necessarily, nonlinear driving of the heat bath by the external noise.

  9. Structural and mutagenesis studies of soluble methane monooxygenase reductase from Methylococcus capsulatus (Bath)

    E-print Network

    Chatwood, Lisa L., 1979-

    2004-01-01

    The solution structure for the 27 kDa flavin binding domain of soluble methane monooxygenase reductase from Methylococcus capsulatus (Bath) was solved by NMR spectroscopy. The structure consists of a two domains, an FAD ...

  10. Non-Markovian dynamics of a qubit coupled to an Ising spin bath

    SciTech Connect

    Krovi, Hari [Department of Electrical Engineering, University of Southern California, Los Angeles, California 90089 (United States); Oreshkov, Ognyan [Department of Physics, University of Southern California, Los Angeles 90089 (United States); Ryazanov, Mikhail [Department of Chemistry, University of Southern California, Los Angeles, California 90089 (United States); Lidar, Daniel A. [Department of Electrical Engineering, University of Southern California, Los Angeles, California 90089 (United States); Department of Physics, University of Southern California, Los Angeles 90089 (United States); Department of Chemistry, University of Southern California, Los Angeles, California 90089 (United States)

    2007-11-15

    We study the analytically solvable Ising model of a single qubit system coupled to a spin bath. The purpose of this study is to analyze and elucidate the performance of Markovian and non-Markovian master equations describing the dynamics of the system qubit, in comparison to the exact solution. We find that the time-convolutionless master equation performs particularly well up to fourth order in the system-bath coupling constant, in comparison to the Nakajima-Zwanzig master equation. Markovian approaches fare poorly due to the infinite bath correlation time in this model. A recently proposed post-Markovian master equation performs comparably to the time-convolutionless master equation for a properly chosen memory kernel, and outperforms all the approximation methods considered here at long times. Our findings shed light on the applicability of master equations to the description of reduced system dynamics in the presence of spin baths.

  11. Quantum many-body theory for qubit decoherence in a finite-size spin bath

    SciTech Connect

    Yang Wen; Liu Renbao [Department of Physics, Chinese University of Hong Kong, Shatin, N. T., Hong Kong (China)

    2008-11-07

    We develop a cluster-correlation expansion theory for the many-body dynamics of a finite-size spin bath in a time scale relevant to the decoherence of a center spin or qubit embedded in the bath. By introducing the cluster correlation as the evolution of a group of bath spins divided by the correlations of all the subgroups, the propagator of the whole bath is factorized into the product of all possible cluster correlations. Each cluster-correlation term accounts for the authentic (non-factorizable) collective excitations within that group. Convergent results can be obtained by truncating the cluster-correlation expansion up to a certain cluster size, as verified in an exactly solvable spin-chain model.

  12. 75 FR 33683 - Third Party Testing for Certain Children's Products; Infant Bath Seats: Requirements for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-15

    ...COMMISSION 16 CFR Part 1215 [CPSC Docket No. CPSC-2009-0064] Third Party Testing for Certain Children's Products; Infant Bath Seats: Requirements for Accreditation of Third Party Conformity Correction In rule document 2010-13080 beginning...

  13. Dissipation and decoherence induced by collective dephasing in coupled-qubit system with a common bath

    E-print Network

    Z. H. Wang; Y. J. Ji; Yong Li; D. L. Zhou

    2014-08-31

    The longitudinal coupling of a system to the bath usually induces the pure dephasing of the system. In this paper, we study the collective dephasing induced dissipation and decoherence in a coupled-qubit system with a common bath. It is shown that, compared with the case of the same system with independent baths, the interference between the dephasing processes of different qubits induced by the common bath significantly changes the dissipation of the system. For the system of two coupled qubits, the interference leads to a faster decoherence in the non-single-excitation subspaces and a slower dissipation (and decoherence) in the single-excitation subspace. For the system of multiple coupled qubits, we also find the slower dissipation in the single-excitation subspace and obtain the decay rates of the first excited states for different system sizes numerically. All our results on collective dephasing induced dissipation can be explained based on a simple model with Fermi's golden rule.

  14. Eggs and milk: Spinning spheres partially immersed in a liquid bath

    NASA Astrophysics Data System (ADS)

    Langley, Kenneth R.; Maynes, Daniel; Truscott, Tadd T.

    2015-03-01

    When a hard-boiled egg spins through a pool of milk on the kitchen counter, the milk rises up the sides of the egg and droplets are ejected. This phenomenon occurs when any partially submerged object whose radius increases upward from the fluid surface (e.g., spheres, inverted cones, and rings) spins in a liquid bath. The fluid ejects from the surface near the maximum radius in one of three ejection modes: jets, sheets, or sheet breakup. Additionally, a surprisingly large flow rate is induced by the spinning object. In this study, we used spheres to determine the effects of experimental parameters on the induced flow rate. We characterized the modes of ejection and measured the sheet breakup distance using high-speed imaging. The basis of our closed form analytical model utilizes an integral momentum boundary layer analysis both beneath the free surface and in the thin film attached to the sphere. We present criteria defining the transitions between ejection modes and the radius where liquid sheets break up in the sheet ejection regime. Criteria defining the transitions between ejection modes and the radius where liquid sheets break up in the sheet ejection regime shows good agreement with experiments.

  15. New method for determination of trihalomethanes in exhaled breath: applications to swimming pool and bath environments.

    PubMed

    Lourencetti, Carolina; Ballester, Clara; Fernández, Pilar; Marco, Esther; Prado, Celia; Periago, Juan F; Grimalt, Joan O

    2010-03-01

    A method for the estimation of the human intake of trihalomethanes (THMs), namely chloroform, bromodichloromethane, dibromochloromethane and bromoform, during showering and bathing is reported. The method is based on the determination of these compounds in exhaled breath that is collected by solid adsorption on Tenax using a device specifically designed for this purpose. Instrumental measurements were performed by automatic thermal desorption coupled to gas chromatography with electron capture detection. THMs in exhaled breath samples were determined during showering and swimming pool attendance. The levels of these compounds in indoor air and water were also determined as reference for interpretation of the exhaled breath results. The THM concentrations in exhaled breath of the volunteers measured before the exposure experiments showed a close correspondence with the THMs levels in indoor air where the sampler was located. Limits of detection in exhaled breath were dependent on THM analytes and experimental sites. They ranged between 170 and 710 ng m(-3) in the swimming pool studies and between 97 and 460 ng m(-3) in the showering studies. Application of this method to THMs determination during showering and swimming pool activities revealed statistically significant increases in THMs concentrations when comparing exhaled breath before and after exposure. PMID:20152261

  16. Stabilization of photon collapse and revival dynamics by a non-Markovian phonon bath

    NASA Astrophysics Data System (ADS)

    Carmele, Alexander; Knorr, Andreas; Milde, Frank

    2013-10-01

    Solid state-based light emitters such as semiconductor quantum dots (QDs) have been demonstrated to be versatile candidates to study the fundamentals of light-matter interaction. In contrast to optics with isolated atomic systems, in the solid-state dissipative processes are induced by the inherent coupling to the environment and are typically perceived as a major obstacle toward stable performances in experiments and applications. In this theoretical model study we show that this is not necessarily the case. In fact, in certain parameter regimes, the memory of the solid-state environment can enhance coherent quantum optical effects. In particular, we demonstrate that the non-Markovian coupling to an incoherent phonon bath can exhibit a stabilizing effect on the coherent QD cavity-quantum electrodynamics by inhibiting irregular oscillations and allowing for regular collapse and revival patterns. For self-assembled GaAs/InAs QDs at low photon numbers we predict dynamics that deviate dramatically from the well-known atomic Jaynes-Cummings model. Even if the required sample parameters are not yet available in recent experimental achievements, we believe our proposal opens the way to a systematic and deliberate design of photon quantum effects via specifically engineered solid-state environments.

  17. Membrane-associated methane monooxygenase from Methylococcus capsulatus (Bath).

    PubMed Central

    Zahn, J A; DiSpirito, A A

    1996-01-01

    An active preparation of the membrane-associated methane monooxygenase (pMMO) from Methylococcus capsulatus Bath was isolated by ion-exchange and hydrophobic interaction chromatography using dodecyl beta-D-maltoside as the detergent. The active preparation consisted of three major polypeptides with molecular masses of 47,000, 27,000, and 25,000 Da. Two of the three polypeptides (those with molecular masses of 47,000 and 27,000 Da) were identified as the polypeptides induced when cells expressing the soluble MMO are switched to culture medium in which the pMMO is expressed. The 27,000-Da polypeptide was identified as the acetylene-binding protein. The active enzyme complex contained 2.5 iron atoms and 14.5 copper atoms per 99,000 Da. The electron paramagnetic resonance spectrum of the enzyme showed evidence for a type 2 copper center (g perpendicular = 2.057, g parallel = 2.24, and magnitude of A parallel = 172 G), a weak high-spin iron signal (g = 6.0), and a broad low-field (g = 12.5) signal. Treatment of the pMMO with nitric oxide produced the ferrous-nitric oxide derivative observed in the membrane fraction of cells expressing the pMMO. When duroquinol was used as a reductant, the specific activity of the purified enzyme was 11.1 nmol of propylene oxidized.min-1.mg of protein-1, which accounted for approximately 30% of the cell-free propylene oxidation activity. The activity was stimulated by ferric and cupric metal ions in addition to the cytochrome b-specific inhibitors myxothiazol and 2-heptyl-4-hydroxyquinoline-N-oxide. PMID:8576034

  18. CdS thin films from two different chemical baths—structural and optical analysis

    Microsoft Academic Search

    S. Prabahar; M. Dhanam

    2005-01-01

    Cadmium sulphide (CdS) thin films of different thicknesses were prepared by the chemical bath deposition technique (CBD) onto well-cleaned glass substrates at 80°C from two chemical baths of different pH values 10 and 11. The thickness of the deposited films has been determined by gravimetry technique. The structural characterization was carried out by X-ray diffraction (XRD) and scanning electron microscopic

  19. Determination of additives in an electrolytic zinc bath by q 1 H-NMR spectroscopy

    Microsoft Academic Search

    Ainara Barriola; José I. Miranda; Miren Ostra; Carlos Ubide

    2010-01-01

    The use of proton nuclear magnetic resonance (1H-NMR) for the quantification of additives in an electrolytic Zn bath is reported. A simple and quick method is described\\u000a that does not need any prior sample preparation. Contrary to other analytical methods, the three additives in the bath, benzylidene\\u000a acetone (BDA), benzoic acid (BA) and poly(ethylene glycol) (PE400), can be quantified. Two

  20. Effect of ammonium sulphate on chemical bath deposition of CdS thin films

    Microsoft Academic Search

    S. Soundeswaran; O. Senthil Kumar; R. Dhanasekaran

    2004-01-01

    CdS semiconductor thin films have been deposited by chemical bath technique from an aqueous solution consisting of cadmium sulphate and thiourea. The deposition of CdS thin films depends on various parameters like pH, temperature, concentration of complexing agents and concentration of reactants (cadmium sulphate and thiourea). The ammonia evaporation from bath affects the pH of the solution and hence the