monovalent potassium gold: Topics by WorldWideScience.org

Sample records for monovalent potassium gold

Interaction between gold (III) chloride and potassium hexacyanoferrate (II/III)-Does it lead to gold analogue of Prussian blue?

Energy Technology Data Exchange (ETDEWEB)

Harish, S. [Electrodics and Electrocatalysis Division, CSIR-Central Electrochemical Research Institute, Karaikudi 630006, Tamilnadu (India); Joseph, James, E-mail: jameskavlam@yahoo.com [Electrodics and Electrocatalysis Division, CSIR-Central Electrochemical Research Institute, Karaikudi 630006, Tamilnadu (India); Phani, K.L.N. [Electrodics and Electrocatalysis Division, CSIR-Central Electrochemical Research Institute, Karaikudi 630006, Tamilnadu (India)

2011-06-30

Highlights: > In group IB, Cu and Ag form Prussian blue analogues but similar formation of gold hexacyanoferrate was not found in the literature and non-existence of gold hexacyanoferrate remains a mystery. > Potential cycling of gold chloride and potassium ferro/ferri cyanide was resulted in the formation of Au-PB nano-composite. > Redox reaction between gold chloride and potassium ferrocyanide ion is spontaneous but no reaction occurs when gold chloride and potassium ferricyanide is mixed. > We are proposing the formation of a compound with general formula 'KFe{sub x}[Au(CN){sub 2}]{sub y}' and discussing the formation of gold hexacyanoferrate is not feasible by simple chemical or electrochemical reaction in contrast to other PB analogues. - Abstract: Prussian blue analogues are a class of compounds formed by the reaction between metal salt and potassium hexacyanoferrate (II/III). In our earlier report, the formation of Au-Prussian blue nano-composite was noticed on potential cycling the glassy carbon electrode in a medium containing gold (III) chloride and potassium hexacyanoferrate (III). Hence in this work, the formation of gold hexacyanoferrate was attempted by a simple chemical reaction. The reaction of gold (III) chloride with potassium hexacyanoferrate (II/III) was examined by UV-Vis spectroscopy and found that there is no redox reaction between gold (III) chloride and potassium hexacyanoferrate (III). However, the redox reaction occurs between gold (III) chloride and potassium hexacyanoferrate (II) leading to the formation of charge transfer band and the conversion of hexacyanoferrate (II) to hexacyanoferrate (III) was evidenced by the emergence of new absorption peaks in UV-Vis spectra. The oxidation state of gold in Au-Fe complex was found to be +1 from X-ray photoelectron spectroscopy. The stability of the Au-Fe complex was also studied by cyclic voltammetry. Cyclic voltammetric results indicated the presence of high spin iron in Au
Interaction between gold (III) chloride and potassium hexacyanoferrate (II/III)-Does it lead to gold analogue of Prussian blue?

International Nuclear Information System (INIS)

Harish, S.; Joseph, James; Phani, K.L.N.

2011-01-01

Highlights: → In group IB, Cu and Ag form Prussian blue analogues but similar formation of gold hexacyanoferrate was not found in the literature and non-existence of gold hexacyanoferrate remains a mystery. → Potential cycling of gold chloride and potassium ferro/ferri cyanide was resulted in the formation of Au-PB nano-composite. → Redox reaction between gold chloride and potassium ferrocyanide ion is spontaneous but no reaction occurs when gold chloride and potassium ferricyanide is mixed. → We are proposing the formation of a compound with general formula 'KFe x [Au(CN) 2 ] y ' and discussing the formation of gold hexacyanoferrate is not feasible by simple chemical or electrochemical reaction in contrast to other PB analogues. - Abstract: Prussian blue analogues are a class of compounds formed by the reaction between metal salt and potassium hexacyanoferrate (II/III). In our earlier report, the formation of Au-Prussian blue nano-composite was noticed on potential cycling the glassy carbon electrode in a medium containing gold (III) chloride and potassium hexacyanoferrate (III). Hence in this work, the formation of gold hexacyanoferrate was attempted by a simple chemical reaction. The reaction of gold (III) chloride with potassium hexacyanoferrate (II/III) was examined by UV-Vis spectroscopy and found that there is no redox reaction between gold (III) chloride and potassium hexacyanoferrate (III). However, the redox reaction occurs between gold (III) chloride and potassium hexacyanoferrate (II) leading to the formation of charge transfer band and the conversion of hexacyanoferrate (II) to hexacyanoferrate (III) was evidenced by the emergence of new absorption peaks in UV-Vis spectra. The oxidation state of gold in Au-Fe complex was found to be +1 from X-ray photoelectron spectroscopy. The stability of the Au-Fe complex was also studied by cyclic voltammetry. Cyclic voltammetric results indicated the presence of high spin iron in Au-Fe complex. Hence 'as
Potassium Permanganate as an Alternative for Gold Mining Wastewater Treatment

Science.gov (United States)

Ordiales, M.; Fernández, D.; Verdeja, L. F.; Sancho, J.

2015-09-01

The feasibility of using potassium permanganate as a reagent for cyanide oxidation in wastewater was experimentally studied. Both artificial and production wastewater from two different gold mines were tested. The experiments had three goals: determine the optimum reagent concentration and reaction time required to achieve total cyanide removal, obtain knowledge of the reaction kinetics, and improve the management of the amount of reagent. The results indicate that potassium permanganate is an effective and reliable oxidizing agent for the removal of cyanide from gold mining wastewater.
Strong and Reversible Monovalent Supramolecular Protein Immobilization

NARCIS (Netherlands)

Young, Jacqui F.; Nguyen, Hoang D.; Yang, Lanti; Huskens, Jurriaan; Jonkheijm, Pascal; Brunsveld, Luc

2010-01-01

Proteins with an iron clasp: Site-selective incorporation of a ferrocene molecule into a protein allows for easy, strong, and reversible supramolecular protein immobilization through a selective monovalent interaction of the ferrocene with a cucurbit[7]uril immobilized on a gold surface. The
Salinity effect on seedling growth, water, sodium and potassium ...

African Journals Online (AJOL)

Mature leaves exhibited good adaptative behavior toward salinity stress by increasing succulence due to absorption of large quantities of water and K+ in leaves. Potassium uptake in leaves was not found to be affected by NaCl concentration. As a consequence, monovalent cations adsorption resulted in an increase in the ...
Impact of monovalent cations on soil structure. Part I. Results of an Iranian soil

Science.gov (United States)

Farahani, Elham; Emami, Hojat; Keller, Thomas; Fotovat, Amir; Khorassani, Reza

2018-01-01

This study investigated the impact of monovalent cations on clay dispersion, aggregate stability, soil pore size distribution, and saturated hydraulic conductivity on agricultural soil in Iran. The soil was incubated with treatment solutions containing different concentrations (0-54.4 mmol l-1) of potassium and sodium cations. The treatment solutions included two levels of electrical conductivity (EC=3 or 6 dS m-1) and six K:Na ratios per electrical conductivity level. At both electrical conductivity levels, spontaneously dispersible clay increased with increasing K concentration, and with increasing K:Na ratio. A negative linear relationship between percentage of water-stable aggregates and spontaneously dispersible clay was observed. Clay dispersion generally reduced the mean pore size, presumably due to clogging of pores, resulting in increased water retention. At both electrical conductivity levels, hydraulic conductivity increased with increasing exchangeable potassium percentage at low exchangeable potassium percentage values, but decreased with further increases in exchangeable potassium percentage at higher exchangeable potassium percentage. This is in agreement with earlier studies, but seems in conflict with our data showing increasing spontaneously dispersible clay with increasing exchangeable potassium percentage. Our findings show that clay dispersion increased with increasing K concentration and increasing K:Na ratio, demonstrating that K can have negative impacts on soil structure.
Oxygen reduction of several gold alloys in 1-molar potassium hydroxide

Science.gov (United States)

Miller, R. O.

1975-01-01

With rotated disk-and-ring equipment, polarograms and other electrochemical measurements were made of oxygen reduction in 1-molar potassium hydroxide on an equiatomic gold-copper (Au-Cu) alloy and a Au-Cu alloy doped with either indium (In) or cobalt (Co) and on Au doped with either nickel (Ni) or platinum (Pt). The results were compared with those for pure Au and pure Pt. The two-electron reaction dominated on all Au alloys as it did on Au. The polarographic results at lower polarization potentials were compared, assuming exclusively a two-step reduction. A qualified ranking of cathodic electrocatalytic activity on the freshly polished reduced disks was indicated: anodized Au Au-Cu-In Au-Cu Au-Cu-Co is equivalent or equal to Au-Pt Au-Ni. Aging in distilled water improved the electrocatalytic efficiency of Au-Cu-Co, Au-Cu, and (to a lesser extent) Au-Cu-In.
Luminescent sulfides of monovalent and trivalent cations

International Nuclear Information System (INIS)

1975-01-01

The invention discloses a family of luminescent materials or phosphors having a rhombohedral crystal structure and consisting essentially of a mixed host sulfide of at least one monovalent host cation and at least one trivalent host cation, and containing, for each mole of phosphor, 0.0005 to 0.05 mole of at least one activating cation. The monovalent host cations may be Na, K or Rb and Cs. The trivalent host cations may be Gd, La, Lu, Sc and Y. The activating cations may be one or more of trivalent As, Bi, Ce, Dy, Er, Pr, Sb, Sm, Tb and Tm; divalent Lu, Mn, Pb and Sn; and monovalent Ag, Cu and Tl. The novel phosphors may be used in devices to convert electron-beam, ultraviolet or x-ray energy to light in the visible spectrum. Such energy conversion can be employed for example in fluoroscopic screens, and in viewing screens of cathode-ray tubes and other electron tubes
Moessbauerspectroscopy on Gold Ruby Glass

International Nuclear Information System (INIS)

Haslbeck, S.

2005-01-01

In this thesis, the chemical states of gold and the physical mechanisms of the growing process of the particles under the influence of additional ingredients like tin, lead, antimony and selenium before, during and after the colouring process are investigated by using the Moessbauer spectroscopy on 197 Au, 119 Sn and 121 Sb, optical spectroscopy and X-ray-diffraction. Gold in an unnealed, colourless state of the glasses consists of monovalent forming linear bonds to two neighbouring oxygen atoms. The Lamb-Moessbauer factor of these gold oxide bondings is observed as 0.095 at 4.2 K. The gold in it's oxide state transforms to gold particles with a diameter of 3 nm to 60 nm. The size of the gold particles is quite definable within the optical spectra and certain sizes are also discernable within the Moessbauer spectra. One component of the Moessbauer spectra is assigned to the surface layer of the gold particles. By comparing this surface component with the amount of the bulk metallic core, one can calculate the size of the gold particles. In the Moessbauer spectra of the colourless glass one also can find parts of bulk metallic gold. Investigations with X-ray diffraction show that these are gold particles with a diameter of 100 nm to 300 nm and therefore have no additional colouring effect within the visible spectrum. The Moessbauer spectra on gold of the remelt glasses are similar to those which have been measured on the initial colourless glasses
Simultaneous Analysis of Monovalent Anions and Cations with a Sub-Microliter Dead-Volume Flow-Through Potentiometric Detector for Ion Chromatography

Science.gov (United States)

Dumanli, Rukiye; Attar, Azade; Erci, Vildan; Isildak, Ibrahim

2016-01-01

A microliter dead-volume flow-through cell as a potentiometric detector is described in this article for sensitive, selective and simultaneous detection of common monovalent anions and cations in single column ion chromatography for the first time. The detection cell consisted of less selective anion- and cation-selective composite membrane electrodes together with a solid-state composite matrix reference electrode. The simultaneous separation and sensitive detection of sodium (Na+), potassium (K+), ammonium (NH4+), chloride (Cl−) and nitrate (NO3−) in a single run was achieved by using 98% 1.5 mM MgSO4 and 2% acetonitrile eluent with a mixed-bed ion-exchange separation column without suppressor column system. The separation and simultaneous detection of the anions and cations were completed in 6 min at the eluent flow-rate of 0.8 mL/min. Detection limits, at S/N = 3, were ranged from 0.2 to 1.0 µM for the anions and 0.3 to 3.0 µM for the cations, respectively. The developed method was successfully applied to the simultaneous determination of monovalent anions and cations in several environmental and biological samples. PMID:26786906
Monovalent Strep-Tactin for strong and site-specific tethering in nanospectroscopy.

Science.gov (United States)

Baumann, Fabian; Bauer, Magnus S; Milles, Lukas F; Alexandrovich, Alexander; Gaub, Hermann E; Pippig, Diana A

2016-01-01

Strep-Tactin, an engineered form of streptavidin, binds avidly to the genetically encoded peptide Strep-tag II in a manner comparable to streptavidin binding to biotin. These interactions have been used in protein purification and detection applications. However, in single-molecule studies, for example using atomic force microscopy-based single-molecule force spectroscopy (AFM-SMFS), the tetravalency of these systems impedes the measurement of monodispersed data. Here, we introduce a monovalent form of Strep-Tactin that harbours a unique binding site for Strep-tag II and a single cysteine that allows Strep-Tactin to specifically attach to the atomic force microscope cantilever and form a consistent pulling geometry to obtain homogeneous rupture data. Using AFM-SMFS, the mechanical properties of the interaction between Strep-tag II and monovalent Strep-Tactin were characterized. Rupture forces comparable to biotin:streptavidin unbinding were observed. Using titin kinase and green fluorescent protein, we show that monovalent Strep-Tactin is generally applicable to protein unfolding experiments. We expect monovalent Strep-Tactin to be a reliable anchoring tool for a range of single-molecule studies.
Electrochemical Oxidation of Glycerol Using Gold Electrode

International Nuclear Information System (INIS)

Mohamed Rozali Othman; Amirah Ahmad

2015-01-01

Cyclic voltammetry, potential linear V and chronocuolometry methods were carried out to gain electrochemical behavior of glycerol at a gold electrode. Potassium hydroxide and sulfuric acid were chosen to be the electrolyte for the electro-oxidation of this organic compound. Besides gold plate electrode, gold composite electrode (Au-PVC) was also used as the working electrode. The Au-PVC composite electrode was characterized by Scanning Electron Microscopy (SEM) to determine its morphological aspects before and after used in electrochemical oxidation of glycerol. In alkaline solution, the adsorption of hydroxide species onto the surface of both gold plate and composite Au-PVC electrodes occurs at potential around 500 mV vs SCE. However, at gold plate electrode, there was a small, broad peak before the drastic escalation of current densities which indicates the charge transfer of the chemisorbed OH - anion. In acidic media, the gold oxide was formed after potential 1.0 V. From the cyclic voltammogram glycerol undergo oxidation twice in potassium hydroxide at gold plate and Au-PVC composite electrodes, while in sulfuric acid, oxidation reaction happened once for glycerol on the gold plate electrode. Overall, electrochemical oxidation of glycerol was more effective in alkaline media. Tafel graph which plotted from potential linear V method shows that Au-PVC composite electrode is better than gold plate electrode for the electro-oxidation of glycerol in alkaline solution. Electrochemical oxidation of glycerol products as analyzed by Gas Chromatography-Mass Spectrometry (GC-MS) produced several carboxylic acids and phenolic compounds. (author)
Hydrofluorination of Alkynes Catalysed by Gold Bifluorides.

Science.gov (United States)

Nahra, Fady; Patrick, Scott R; Bello, Davide; Brill, Marcel; Obled, Alan; Cordes, David B; Slawin, Alexandra M Z; O'Hagan, David; Nolan, Steven P

2015-01-01

We report the synthesis of nine new N -heterocyclic carbene gold bifluoride complexes starting from the corresponding N -heterocyclic carbene gold hydroxides. A new methodology to access N,N' -bis(2,6-diisopropylphenyl)imidazol-2-ylidene gold(I) fluoride starting from N,N' -bis(2,6-diisopropylphenyl)imidazol-2-ylidene gold(I) hydroxide and readily available potassium bifluoride is also reported. These gold bifluorides were shown to be efficient catalysts in the hydrofluorination of symmetrical and unsymmetrical alkynes, thus affording fluorinated stilbene analogues and fluorovinyl thioethers in good to excellent yields with high stereo- and regioselectivity. The method is exploited further to access a fluorinated combretastatin analogue selectively in two steps starting from commercially available reagents.
Monovalent IgG4 molecules

Science.gov (United States)

Wilkinson, Ian C.; Fowler, Susan B.; Machiesky, LeeAnn; Miller, Kenneth; Hayes, David B.; Adib, Morshed; Her, Cheng; Borrok, M. Jack; Tsui, Ping; Burrell, Matthew; Corkill, Dominic J.; Witt, Susanne; Lowe, David C.; Webster, Carl I.

2013-01-01

Antibodies have become the fastest growing class of biological therapeutics, in part due to their exquisite specificity and ability to modulate protein-protein interactions with a high biological potency. The relatively large size and bivalency of antibodies, however, limits their use as therapeutics in certain circumstances. Antibody fragments, such as single-chain variable fragments and antigen binding-fragments, have emerged as viable alternatives, but without further modifications these monovalent formats have reduced terminal serum half-lives because of their small size and lack of an Fc domain, which is required for FcRn-mediated recycling. Using rational engineering of the IgG4 Fc domain to disrupt key interactions at the CH3-CH3 interface, we identified a number of point mutations that abolish Fc dimerization and created half-antibodies, a novel monovalent antibody format that retains a monomeric Fc domain. Introduction of these mutations into an IgG1 framework also led to the creation of half-antibodies. These half-antibodies were shown to be soluble, thermodynamically stable and monomeric, characteristics that are favorable for use as therapeutic proteins. Despite significantly reduced FcRn binding in vitro, which suggests that avidity gains in a dimeric Fc are critical to optimal FcRn binding, this format demonstrated an increased terminal serum half-life compared with that expected for most alternative antibody fragments. PMID:23567207
Tumour targeting with monovalent fragments of anti-neuroblastoma antibody chCE7

International Nuclear Information System (INIS)

Carrel, F.; Novak-Hofer, I.; Ruch, C.; Zimmermann, K.; Amstutz, H.

1997-01-01

The in vitro and in vivo behaviour of the monovalent single chain (scFv) and Fab-fragments derived from anti-neuroblastoma antibody chCE7 is reported. When comparing tumour uptake and -retention of radioactivity of 67 Cu-labelled monovalent chCE7 with divalent chCE7 F(ab') 2 the advantage of the radiocopper label over the radioiodine label was more pronounced with the divalent (internalising) F(ab') 2 fragments. (author) 1 fig., 1 ref
Selective removal of arsenic and monovalent ions from brackish water reverse osmosis concentrate.

Science.gov (United States)

Xu, Pei; Capito, Marissa; Cath, Tzahi Y

2013-09-15

Concentrate disposal and management is a considerable challenge for the implementation of desalination technologies, especially for inland applications where concentrate disposal options are limited. This study has focused on selective removal of arsenic and monovalent ions from brackish groundwater reverse osmosis (RO) concentrate for beneficial use and safe environmental disposal using in situ and pre-formed hydrous ferric oxides/hydroxides adsorption, and electrodialysis (ED) with monovalent permselective membranes. Coagulation with ferric salts is highly efficient at removing arsenic from RO concentrate to meet a drinking water standard of 10 μg/L. The chemical demand for ferric chloride however is much lower than ferric sulfate as coagulant. An alternative method using ferric sludge from surface water treatment plant is demonstrated as an efficient adsorbent to remove arsenic from RO concentrate, providing a promising low cost, "waste treat waste" approach. The monovalent permselective anion exchange membranes exhibit high selectivity in removing monovalent anions over di- and multi-valent anions. The transport of sulfate and phosphate through the anion exchange membranes was negligible over a broad range of electrical current density. However, the transport of divalent cations such as calcium and magnesium increases through monovalent permselective cation exchange membranes with increasing current density. Higher overall salt concentration reduction is achieved around limiting current density while higher normalized salt removal rate in terms of mass of salt per membrane area and applied energy is attained at lower current density because the energy unitization efficiency decreases at higher current density. Copyright © 2013 Elsevier B.V. All rights reserved.
Immunogenic Response of Rabbits to Monovalent and Polyvalent ...

African Journals Online (AJOL)

This work was carried out in University of Surrey UK Department of Microbiology. In this study, the efficacy of monovalent and polyvalent vaccines made from Mannhaemia haemolytica antigens, were evaluated by measuring specific serum antibody titers produced against the bacteria in immunized rabbits. Eleven biotype A ...
Polyelectrolyte-modified cowpea mosaic virus for the synthesis of gold nanoparticles.

Science.gov (United States)

Aljabali, Alaa A A; Evans, David J

2014-01-01

Polyelectrolyte surface-modified cowpea mosaic virus (CPMV) can be used for the templated synthesis of narrowly dispersed gold nanoparticles. Cationic polyelectrolyte, poly(allylamine) hydrochloride, is electrostatically bound to the external surface of the virus capsid. The polyelectrolyte-coated CPMV promotes adsorption of aqueous gold hydroxide anionic species, prepared from gold(III) chloride and potassium carbonate, that are easily reduced to form CPMV-templated gold nanoparticles. The process is simple and environmentally benign using only water as solvent at ambient temperature.
Gold nanoparticle growth control - Implementing novel wet chemistry method on silicon substrate

KAUST Repository

Al-Ameer, Ammar

2013-04-01

Controlling particle size, shape, nucleation, and self-assembly on surfaces are some of the main challenges facing electronic device fabrication. In this work, growth of gold nanoparticles over a wide range of sizes was investigated by using a novel wet chemical method, where potassium iodide is used as the reducing solution and gold chloride as the metal precursor, on silicon substrates. Four parameters were studied: soaking time, solution temperature, concentration of the solution of gold chloride, and surface pre-treatment of the substrate. Synthesized nanoparticles were then characterized using scanning electron microscopy (SEM). The precise control of the location and order of the grown gold overlayer was achieved by using focused ion beam (FIB) patterning of a silicon surface, pre-treated with potassium iodide. By varying the soaking time and temperature, different particle sizes and shapes were obtained. Flat geometrical shapes and spherical shapes were observed. We believe, that the method described in this work is potentially a straightforward and efficient way to fabricate gold contacts for microelectronics. © 2013 IEEE.
Distribution and composition of gold in porphyry gold systems: example from the Biely Vrch deposit, Slovakia

Science.gov (United States)

Koděra, Peter; Kozák, Jaroslav; Brčeková, Jana; Chovan, Martin; Lexa, Jaroslav; Jánošík, Michal; Biroň, Adrián; Uhlík, Peter; Bakos, František

2018-03-01

The Biely Vrch deposit in the Western Carpathians is assigned to the shallow, sulfide-poor porphyry gold deposit type and has an exceptionally low Cu/Au ratio. According to 3-D geochemical models, there is a limited spatial correlation between Au and Cu due to the primary introduction of gold by a salt melt and Cu by low-density vapor. Despite a rough spatial correlation of gold grades with quartz stockwork intensity, gold is hosted mostly by altered rock, exclusively in native form. Three main gold mineral assemblages were recognized here. In the deepest parts of the system, the K- and Ca-Na silicate gold assemblage is associated with minerals of high-temperature alteration (plagioclase, K-feldspar, actinolite), with gold grades and fineness depending on depth and potassium content of the host rock: K-silicate alteration hosts the lowest fineness gold ( 914), whereas Ca-Na silicate alteration has the highest ( 983). The intermediate argillic gold assemblage is the most widespread, with gold hosted mainly by chlorite, illite, smectite, and interstratified illite-chlorite-smectite minerals. The gold fineness is mostly variable (875-990) and inherited from the former gold mineral assemblages. The latest advanced argillic gold assemblage has its gold mostly in kaolinite. The extremely high fineness ( 994) results from gold remobilization by late-stage aqueous magmatic-hydrothermal fluids. Uncommon bonanza-grade appears where the earlier gold mineral assemblages were further enriched by this remobilized gold. Primary precipitation of gold occurred during ascent and cooling of salt melts at 450 to 309 °C, mostly during retrograde quartz solubility.

Multivalent protein assembly using monovalent self-assembling building blocks

NARCIS (Netherlands)

Petkau - Milroy, K.; Sonntag, M.H.; Colditz, A.; Brunsveld, L.

2013-01-01

Discotic molecules, which self-assemble in water into columnar supramolecular polymers, emerged as an alternative platform for the organization of proteins. Here, a monovalent discotic decorated with one single biotin was synthesized to study the self-assembling multivalency of this system in regard
Empirical formula for the parameters of metallic monovalent halides ...

African Journals Online (AJOL)

By collating the data on melting properties and transport coefficients obtained from various experiments and theories for certain halides of monovalent metals, allinclusive linear relationship has been fashioned out. This expression holds between the change in entropy and volume on melting; it is approximately obeyed by ...
Uses of the potassium permanganate to eliminate copper cyanide from waste water resulting from a lixiviation plant in a gold mine (I)

International Nuclear Information System (INIS)

Sancho, J. P.; Fernandez, B.; Ayala, J.; Garcia, M. P.; Lavandeira, A.

2009-01-01

The use of cyanide in the hydrometallurgical and chemical industries has led to the emergence of a major environmental problem due to its high toxicity. Te wastewater generated at these plants is hazardous to the environment and therefore must be managed properly. For this purpose, they undergo detoxification processes after lodes from the plant are accumulated in waste-resistant containment ponds that mast be waterproof to prevent environmental disasters from leakages or massive flood. This work shows the results obtained in laboratory tests carried out with plant waters and demonstrates the efficacy of potassium permanganate as an oxidant of cyanide wastewater from a gold hydrometallurgical plant. In the process the destruction of the copper cyanide complexes is solution is achieved and copper metal ions are eliminated through precipitation mostly as hydroxide. (Author) 28 refs.
Differential Impact of the Monovalent Ions Li+, Na+, K+, and Rb+ on DNA Conformational Properties

OpenAIRE

Savelyev, Alexey; MacKerell, Alexander D.

2014-01-01

The present report demonstrates that the conformational properties of DNA in solution are sensitive to the type of monovalent ion. Results are based on the ability of a polarizable force field using the classical Drude oscillator to reproduce experimental solution X-ray scattering data more accurately than two nonpolarizable DNA models, AMBER Parmbsc0 and CHARMM36. The polarizable model is then used to calculate scattering profiles of DNA in the presence of four different monovalent salts, Li...
Preparation of colloidal gold for staining proteins electrotransferred onto nitrocellulose membranes.

Science.gov (United States)

Yamaguchi, K; Asakawa, H

1988-07-01

This paper describes a simple method of preparing colloidal gold for staining protein blots. Colloidal gold was prepared from 0.005 or 0.01% HAuCl4 by the addition of formalin as a reductant and potassium hydroxide. Staining of small cell carcinoma tissue extract blotted onto nitrocellulose membranes with this colloidal gold solution resulted in the appearance of a large number of clear wine-red bands. The sensitivity of gold staining was 60 times higher than that of Coomassie brilliant blue staining and almost comparable to that of silver staining of proteins in polyacrylamide gel. The sensitivity of this method was also satisfactory in comparison with that of enzyme immunoblotting. The colloidal gold prepared by this method is usable for routine work.
Electron transport through monovalent atomic wires

DEFF Research Database (Denmark)

Lee, Y. J.; Brandbyge, Mads; Puska, M. J.

2004-01-01

at the chain determine the conductance. As a result, the conductance for noble-metal chains is close to one quantum of conductance, and it oscillates moderately so that an even number of chain atoms yields a higher value than an odd number. The conductance oscillations are large for alkali-metal chains......Using a first-principles density-functional method we model electron transport through linear chains of monovalent atoms between two bulk electrodes. For noble-metal chains the transport resembles that for free electrons over a potential barrier whereas for alkali-metal chains resonance states...... and their phase is opposite to that of noble-metal chains....
Self-assembling multivalency : supramolecular polymers assembled from monovalent mannose-labelled discotic molecules

NARCIS (Netherlands)

Petkau - Milroy, K.; Brunsveld, L.

2013-01-01

Supramolecular synthesis, the "bottom-up" construction of higher-order structures from monomeric building blocks, represents a flexible approach for the generation of multivalent materials. Here, monovalent building blocks decorated with a single bioactive ligand were synthesized. In water, these
Monovalent RIVM meningococcal B OMP vesicle F91 vaccines in toddlers

NARCIS (Netherlands)

Lafeber AB; Limpt CJP van; Labadie J; Berbers GAM; Kleijn ED de; Groot R de; Rumke HC; Alphen AJW; Sophia Kinderziekenhuis /; LVO

2001-01-01

This report gives the results of a randomised phase-II clinical study into the safety and immunogenicity of a monovalent MenB OMV vaccine expressing P1.7h,4 PorA (MonoMen) in toddlers. Safety and immunogenicity are compared for two types of vaccine that are differently adjuvated (either
Thermal study of monovalent-divalent phase transition in npBifc-F1TCNQ System

International Nuclear Information System (INIS)

Sato, Michiko; Nishio, Yutaka; Kajita, Koji; Mochida, Tomoyuki

2009-01-01

In a new molecular solid composed of di-neopentyl-biferrocene (npBifc) and fluorotetracyanoquinodimethane (F 1 TCNQ) 3 , Mochida reported the discovery of a reversible valence transfer that can be regarded as an 'ionic(I)-ionic(II)' phase transfer between the monovalent state (D + A - ) and the divalent state (D 2+ A 2- ). We have studied thermo-dynamical properties of this transformation for this complex using the differential thermal analyses (DTA). We observed a broad excess specific heat with multi-peaks attributed to micro-domain structure over the corresponding temperature range (100-150K) accompanied by temperature hysteresis of 7K. The transition entropy (ΔS) was determined to be 22 ± 2 J/mol-K and almost satisfied a Clausius-Clapeyron relation. These experimental results provide an experimental confirmation of the first order phase transition for the monovalent-divalent transfer. At the transition, we observe that the electronic degrees of freedom remained constant values, while large entropy absorbed crossing from low temperature phase to high temperature one is contributed by the lattice one. We finally estimated the internal energy and concluded that delicate energy valance between Madelung, ionization and affinity energies enable this system to exhibit a temperature induce monovalent-divalent phase transition.
Absorption Spectroscopy Analysis of Calcium-Phosphate Glasses Highly Doped with Monovalent Copper.

Science.gov (United States)

Jiménez, José A

2016-06-03

CaO-P2 O5 glasses with high concentrations of monovalent copper ions were prepared by a simple melt-quench method through CuO and SnO co-doping. Spectroscopic characterization was carried out by optical absorption with the aim of analyzing the effects of Cu(+) ions on the optical band-gap energies, which were estimated on the basis of indirect-allowed transitions. The copper(I) content is estimated in the CuO/SnO-containing glasses after the assessment of the concentration dependence of Cu(2+) absorption in the visible region for CuO singly doped glasses. An exponential dependence of the change in optical band gaps (relative to the host) with Cu(+) concentration is inferred up to about 10 mol %. However, the entire range is divided into two distinct linear regions that are characterized by different rates of change with respect to concentration: 1) below 5 mol %, where the linear dependence presents a relatively high magnitude of the slope; and 2) from 5-10 mol %, where a lower magnitude of the slope is manifested. With increasing concentration, the mean Cu(+) -Cu(+) interionic distance decreases, thereby decreasing the sensitivity of monovalent copper for light absorption. The decrease in optical band-gap energies is ultimately shown to follow a linear dependence with the interionic distance, suggesting the potential of the approach to gauge the concentration of monovalent copper straightforwardly in amorphous hosts. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Substoichiometric neutron activation determination of gold

International Nuclear Information System (INIS)

Mitchell, J.W.; Riley, J.E. Jr.; Payne, V.

1978-01-01

A highly precise and selective method is described for the determination of traces of gold by substoichiometric extraction from hydrochloric acid with tri-n-octylphosphine sulfide in cyclohexane following thermal neutron activation. Fundamental aspects of the extraction system are discussed and results are reported for the determination of gold in an effluent from a recovery process containing a complexed species of gold and unknown amounts of cyanide, citrate, phosphate, potassium and sodium. Other constituents of the effluent stream include traces of the transition elements Co, Ni, Fe, Cu, Zn, Pb and Sn at concentrations less than 50 ppm. One hour was allowed for the Au 3+ carrier and the 198 Au complexed species in samples and standards to oxidize, exchange, and reach chemical equilibrium. Samples were then equilibrated by shaking with the organic phase for thirty min. The percentage extractions (%E) for the substoichiometric separation of gold from the effluent and from the corresponding comparison standards were monitored. The mean percentage extractions for the substoichiometric separations of carrier from the effluent, and its corresponding standard were 75.3 and 59.3, respectively. These data are estimated to be accurate within +-2.0%. (T.G.)
Fouling prevention of peptides from a tryptic whey hydrolysate during electromembrane processes by use of monovalent ion permselective membranes

OpenAIRE

Persico, Mathieu; Bazinet, Laurent

2017-01-01

Peptide adsorption occurring on conventional anion- and cation-exchange membranes is one of the main technological locks in electrodialysis (ED) for hydrolysate demineralization. Hence, the peptide fouling of monovalent anion (MAP) and monovalent cation (MCP) permselective membranes was studied and compared to conventional membranes (AMX-SB and CMX-SB). It appeared that the main peptide sequences responsible for fouling were TPEVDDEALEKFDK, VAGTWY and VLVLDTDYK for both anionic membranes; and...
Aerobic Oxidation of Alcohols over Gold Catalysts: Role of Acid and Base

DEFF Research Database (Denmark)

Klitgaard, Søren Kegnæs; DeLa Riva, Andrew T.; Helveg, Stig

2008-01-01

Gold nanoparticles are deposited on potassium titanate nanowires and used as heterogeneous catalysts in the aerobic oxidation of benzyl alcohol in methanol to methyl benzoate at ambient conditions. The presence of a catalytic amount of base promotes the reaction and the formation of free benzoic...
Thermal study of monovalent-divalent phase transition in npBifc-F{sub 1}TCNQ System

Energy Technology Data Exchange (ETDEWEB)

Sato, Michiko; Nishio, Yutaka; Kajita, Koji [Department of Physics, Faculty of Science, Toho University, Miyama 2-2-1, Funabashi, Chiba, 274-8510 (Japan); Mochida, Tomoyuki, E-mail: nishio@ph.sci.toho-u.ac.j [Department of Chemistry, Faculty of Science, Kobe University, Rokkodai, Nada, Kobe 657-8501 (Japan)

2009-03-01

In a new molecular solid composed of di-neopentyl-biferrocene (npBifc) and fluorotetracyanoquinodimethane (F{sub 1}TCNQ){sub 3}, Mochida reported the discovery of a reversible valence transfer that can be regarded as an 'ionic(I)-ionic(II)' phase transfer between the monovalent state (D{sup +}A{sup -}) and the divalent state (D{sup 2+}A{sup 2-}). We have studied thermo-dynamical properties of this transformation for this complex using the differential thermal analyses (DTA). We observed a broad excess specific heat with multi-peaks attributed to micro-domain structure over the corresponding temperature range (100-150K) accompanied by temperature hysteresis of 7K. The transition entropy (DELTAS) was determined to be 22 +- 2 J/mol-K and almost satisfied a Clausius-Clapeyron relation. These experimental results provide an experimental confirmation of the first order phase transition for the monovalent-divalent transfer. At the transition, we observe that the electronic degrees of freedom remained constant values, while large entropy absorbed crossing from low temperature phase to high temperature one is contributed by the lattice one. We finally estimated the internal energy and concluded that delicate energy valance between Madelung, ionization and affinity energies enable this system to exhibit a temperature induce monovalent-divalent phase transition.
Taguchi optimization: Case study of gold recovery from amalgamation tailing by using froth flotation method

Science.gov (United States)

Sudibyo, Aji, B. B.; Sumardi, S.; Mufakir, F. R.; Junaidi, A.; Nurjaman, F.; Karna, Aziza, Aulia

2017-01-01

Gold amalgamation process was widely used to treat gold ore. This process produces the tailing or amalgamation solid waste, which still contains gold at 8-9 ppm. Froth flotation is one of the promising methods to beneficiate gold from this tailing. However, this process requires optimal conditions which depends on the type of raw material. In this study, Taguchi method was used to optimize the optimum conditions of the froth flotation process. The Taguchi optimization shows that the gold recovery was strongly influenced by the particle size which is the best particle size at 150 mesh followed by the Potassium amyl xanthate concentration, pH and pine oil concentration at 1133.98, 4535.92 and 68.04 gr/ton amalgamation tailing, respectively.
Two-phase coexistence in the monovalent-to-divalent phase transition of dineopentylbiferrocene-fluorotetracyanoquinodimethane [npBifc-(F1TCNQ)3], charge-transfer salt

International Nuclear Information System (INIS)

Uruichi, Mikio; Yue, Yue; Yakushi, Kyuya; Mochida, Tomoyuki

2007-01-01

We present experimental findings showing that for npBifc-(F 1 TCNQ) 3 , two phases coexist over a wide temperature interval of 100-150 K near the monovalent-to-divalent phase transition temperature. Macroscopic domains of the high-temperature (monovalent) and low-temperature (divalent) phases were detected in the transition temperature region using X-ray diffraction and micro-Raman spectroscopy techniques. The volume fraction of the two domains continuously varied depending upon the temperature. A considerably large volume difference was found between the monovalent and divalent phases. The effect of volumetric strain due to this volume difference is discussed to understand this inhomogeneous state. (author)
Ultra-long-term human salt balance studies reveal interrelations between sodium, potassium, and chloride intake and excretion

NARCIS (Netherlands)

Birukov, Anna; Rakova, Natalia; Lerchl, Kathrin; Olde Engberink, Rik H. G.; Johannes, Bernd; Wabel, Peter; Moissl, Ulrich; Rauh, Manfred; Luft, Friedrich C.; Titze, Jens

2016-01-01

The intake of sodium, chloride, and potassium is considered important to healthy nutrition and cardiovascular disease risk. Estimating the intake of these electrolytes is difficult and usually predicated on urine collections, commonly for 24 h, which are considered the gold standard. We reported on
Superconducting state parameters of monovalent and polyvalent amorphous

Energy Technology Data Exchange (ETDEWEB)

Sonvane, Y. A., E-mail: yas@ashd.svnit.ac.in [Department of Applied Physics, S. V. National Institute of Technology, Surat 395 007, Gujarat (India); Patel, H. P., E-mail: patel.harshal2@gmail.com; Thakor, P. B., E-mail: pbthakor@rediffmail.com [Department of Physics, Veer Narmad South Gujarat University, Surat 395 007, Gujarat (India)

2015-08-28

In the present study deals, we have calculated superconducting state parameter (SSP) like electron-phonon coupling strength λ, coulomb pseudo potential, μ*, transition temperature Tc, isotope effect exponent α and effective interaction strength N{sub 0}V of monovalent (Li), divalent (Zn), trivalent (In) and tetravalent (Pb) amorphous. To carry out this work we have used our newly constructed model pseudo potential to describe electron ion interaction along with three different local field correction functions like Hartree, Taylor and Sarkar et al. The present results are found in good agreement with other available theoretical as well as experimental data.
Circular Dichroism is Sensitive to Monovalent Cation Binding in Monensin Complexes

Czech Academy of Sciences Publication Activity Database

Nedzhib, A.; Kessler, Jiří; Bouř, Petr; Gyurcsik, B.; Pantcheva, I.

2016-01-01

Roč. 28, č. 5 (2016), s. 420-428 ISSN 0899-0042 R&D Projects: GA ČR GA15-09072S; GA ČR(CZ) GA16-05935S Institutional support: RVO:61388963 Keywords : monovalent polyether ionophore * metal complexes * synchrotron radiation circular dichroism * time-dependent density functional theory Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.956, year: 2016
Gold recovery from low concentrations using nanoporous silica adsorbent

Science.gov (United States)

Aledresse, Adil

The development of high capacity adsorbents with uniform porosity denoted 5%MP-HMS (5% Mercaptopropyl-Hexagonal Mesoporous Structure) to extract gold from noncyanide solutions is presented. The preliminary studies from laboratory simulated noncyanide gold solutions show that the adsorption capacities of these materials are among the highest reported. The high adsorption saturation level of these materials, up to 1.9 mmol/g (37% of the adsorbent weight) from gold chloride solutions (potassium tetrachloroaurate) and 2.9 mmol/g (57% of the adsorbent weight) from gold bromide solutions (potassium tetrabromoaurate) at pH = 2, is a noteworthy feature of these materials. This gold loading from [AuC4]- and [AuBr4 ]- solutions corresponds to a relative Au:S molar ratio of 2.5:1 and 3.8:1, respectively. These rates are significantly higher than the usual 1:1 (Au:S) ratio expected for metal ion binding with the material. The additional gold ions loaded have been spontaneously reduced to metallic gold in the mesoporous material. Experimental studies indicated high maximum adsorptions of gold as high as 99.9% recovery. Another promising attribute of these materials is their favourable adsorption kinetics. The MP-HMS reaches equilibrium (saturation) in less than 1 minute of exposure in gold bromide and less than 10 minutes in gold chloride. The MP-HMS materials adsorption is significantly improved by agitation and the adsorption capacity of Au (III) ions increases with the decrease in pH. The recovery of adsorbed gold and the regeneration of spent adsorbent were investigated for MP-HMS adsorbent. The regenerated adsorbent (MP-HMS) maintained its adsorption capacity even after repeated use and all the gold was successfully recovered from the spent adsorbent. For the fist time, a promising adsorbent system has been found that is capable of effectively concentrating gold thiosulphate complexes, whereas conventional carbon-inpulp (CIP) and carbon-in-leach (CIL) systems fail. The

The apparent monovalency of human IgG4 is due to bispecificity

NARCIS (Netherlands)

Aalberse, R. C.; Schuurman, J.; van Ree, R.

1999-01-01

A hypothesis is put forward to explain the apparent monovalency of human IgG4. It is based upon the known instability of the IgG4 hinge. IgG4 is secreted as a regular bivalent antibody, but after secretion interacts with another IgG4 molecule. This interaction results in the exchange of half
Monovalent Cation Activation of the Radical SAM Enzyme Pyruvate Formate-Lyase Activating Enzyme.

Science.gov (United States)

Shisler, Krista A; Hutcheson, Rachel U; Horitani, Masaki; Duschene, Kaitlin S; Crain, Adam V; Byer, Amanda S; Shepard, Eric M; Rasmussen, Ashley; Yang, Jian; Broderick, William E; Vey, Jessica L; Drennan, Catherine L; Hoffman, Brian M; Broderick, Joan B

2017-08-30

Pyruvate formate-lyase activating enzyme (PFL-AE) is a radical S-adenosyl-l-methionine (SAM) enzyme that installs a catalytically essential glycyl radical on pyruvate formate-lyase. We show that PFL-AE binds a catalytically essential monovalent cation at its active site, yet another parallel with B 12 enzymes, and we characterize this cation site by a combination of structural, biochemical, and spectroscopic approaches. Refinement of the PFL-AE crystal structure reveals Na + as the most likely ion present in the solved structures, and pulsed electron nuclear double resonance (ENDOR) demonstrates that the same cation site is occupied by 23 Na in the solution state of the as-isolated enzyme. A SAM carboxylate-oxygen is an M + ligand, and EPR and circular dichroism spectroscopies reveal that both the site occupancy and the identity of the cation perturb the electronic properties of the SAM-chelated iron-sulfur cluster. ENDOR studies of the PFL-AE/[ 13 C-methyl]-SAM complex show that the target sulfonium positioning varies with the cation, while the observation of an isotropic hyperfine coupling to the cation by ENDOR measurements establishes its intimate, SAM-mediated interaction with the cluster. This monovalent cation site controls enzyme activity: (i) PFL-AE in the absence of any simple monovalent cations has little-no activity; and (ii) among monocations, going down Group 1 of the periodic table from Li + to Cs + , PFL-AE activity sharply maximizes at K + , with NH 4 + closely matching the efficacy of K + . PFL-AE is thus a type I M + -activated enzyme whose M + controls reactivity by interactions with the cosubstrate, SAM, which is bound to the catalytic iron-sulfur cluster.
Cucurbit[7]uril as a tool in the green synthesis of gold nanoparticles.

Science.gov (United States)

Premkumar, Thathan; Geckeler, Kurt E

2010-12-03

A simple, green, one-pot synthesis of gold nanoparticles was achieved through the reaction of an aqueous mixture of potassium tetrachloroaurate(III) and the macrocycle cucurbit[7]uril in the presence of sodium hydroxide at room temperature without introducing any kind of traditional reducing agents and/or external energy. The as-prepared gold nanoparticles showed catalytic activity for the reduction reaction of 4-nitrophenol in the presence of NaBH(4), which has been established by visual inspection and UV/Vis spectroscopy. This report is the first for the preparation of gold nanoparticles using cucurbit[7]uril in aqueous media through chemical reduction without employing conventional reducing agents and/or external energy.
The Study and Application of Hydrometallurgical Gold Leaching in the Analysis of Refractory Precious Metals

Science.gov (United States)

Yang, M.; Geng, X.; Wang, Y. L.; Li, D. X.

2017-05-01

Three orthogonal tests are separately designed for each hydrometallurgical gold leaching process to finding the optimum reaction conditions of melting gold and palladium in each process. Under the optimum condition, the determination amount of gold and palladium in aqua regia—hydrofluoric acid, Sodium thiosulfate, and potassium iodide reaches 2.87g/kg and 8.34 g/kg, 2.39g/kg and 8.12 g/kg, 2.51g/kg and 7.84g/kg. From the result, the content of gold and palladium using the leaching process of combining Aqua regia, hydrofluoric acid and hydrogen peroxide is relatively higher than the other processes. In addition, the experiment procedure of aqua regia digestion operates easily, using less equipment, and its period is short.
Application of fussy mathematics to the data processing of surface gamma spectrometry for gold exploration

International Nuclear Information System (INIS)

Huang Zheming.

1990-01-01

This paper introduces a new method by applying fuzzy mathematics to the data processing of uranium thorium and potassium, these data were detected from surface gamma spectrometry in the field and can be used to make quantitative interpretation for delineating gold mineralization in the favourable area. This method provides a rapid means for expanding and tracing gold deposits or occurrences and for prospecting gold deposits of the same kind and also provides an effective means for engineering design in uncovering exploration. It is of high efficiency, low cost and worth popularizing. It can be also used to look for other metallic and nonmetallic ore deposits
Chemically controlled interfacial nanoparticle assembly into nanoporous gold films for electrochemical applications

DEFF Research Database (Denmark)

Christiansen, Mikkel U. -B.; Seselj, Nedjeljko; Engelbrekt, Christian

2018-01-01

at the liquid/air interface starting from gold nanoparticles (AuNPs) in an aqueous solution, providing silver-free gold films. Chloroauric acid is reduced to AuNP building blocks by 2-(N-morpholino)ethanesulfonic acid, which also acts as a protecting agent and pH buffer. By adding potassium chloride before Au......, they can be controlled by varying the temperature, chloride concentration, ionic strength, and protonation of the buffer. cNPGF formation is attributed to the destabilization of AuNPs at the air–liquid interface. The developed method generates electrochemically stable cNPGFs up to 20 cm2 in size...
Low Potassium (Hypokalemia)

Science.gov (United States)

Symptoms Low potassium (hypokalemia) By Mayo Clinic Staff Low potassium (hypokalemia) refers to a lower than normal potassium level ... 2 millimoles per liter (mmol/L). A very low potassium level (less than 2.5 mmol/L) ...
Epidemiological and Economic Impact of Monovalent and Pentavalent Rotavirus Vaccines in Low and Middle Income Countries: A Cost-effectiveness Modeling Analysis.

Science.gov (United States)

Paternina-Caicedo, Angel; De la Hoz-Restrepo, Fernando; Alvis-Guzmán, Nelson

2015-07-01

The competing choices of vaccination with either RV1 or RV5, the potential budget impact of vaccines on the EPI with different prices and new evidence make important an updated analysis for health decision makers in each country. The objective of this study is to assess cost-effectiveness of the monovalent and pentavalent rotavirus vaccines and impact on children deaths, inpatient and outpatient visits in 116 low and middle income countries that represent approximately 99% of rotavirus mortality. A decision tree model followed hypothetical cohorts of children from birth up to 5 years of age for each country in 2010. Inputs were gathered from international databases and previous research on incidence and effectiveness of monovalent and pentavalent vaccines. Costs were expressed in 2010 international dollars. Outcomes were reported in terms of cost per disability-adjusted life-year averted, comparing no vaccination with either monovalent or pentavalent mass introduction. Vaccine price was assumed fixed for all world low-income and middle-income countries. Around 292,000 deaths, 3.34 million inpatient cases and 23.09 million outpatient cases would occur with no vaccination. In the base-case scenario, monovalent vaccination would prevent 54.7% of inpatient cases and 45.4% of deaths. Pentavalent vaccination would prevent 51.4% of inpatient cases and 41.1% of deaths. The vaccine was cost-effective in all world countries in the base-case scenario for both vaccines. Cost per disability-adjusted life-year averted in all selected countries was I$372 for monovalent, and I$453 for pentavalent vaccination. Rotavirus vaccine is cost-effective in most analyzed countries. Despite cost-effectiveness analysis is a useful tool for decision making in middle-income countries, for low-income countries health decision makers should also assess the impact of introducing either vaccine on local resources and budget impact analysis of vaccination.
Magnetic, radiometric and gravity signatures of localities of epithermal gold deposits in Fiji

International Nuclear Information System (INIS)

Gunn, Peter J.; Mackey, Tim; Meixner, Tony J.

1998-01-01

Fiji contains several epithermal gold deposits and by studying the geophysical responses in the vicinity of these deposits it is possible to identify a set of geophysical characteristics which indicate localities where such deposits may be located. Epithermal gold deposits are formed above intrusive stocks resulting from subduction processes. The source intrusions for the deposits are normally covered by lavas and pyroclastic rocks and the irregular magnetic effects of these units obscure the magnetic effects of the intrusions. In Fiji however the source intrusions can be recognized as causing gravity highs and magnetic highs in upward continued magnetic data in which the magnetic effects of volcanic rocks are suppressed. Vents associated with the intrusions can be recognized as magnetic lows which sometimes contain a central high. Some vents and calderas can be recognized in digital elevation data. Increased potassium concentrations ca be interpreted to indicate potassium alteration associated with mineralizing processes. Fractures that may localize epithermal deposits can be recognized in the magnetic data and enhancements of the data such as produced by derivative operations. (author)
In vitro neutralisation of rotavirus infection by two broadly specific recombinant monovalent llama-derived antibody fragments

NARCIS (Netherlands)

F. Aladin (Farah); A.W.C. Einerhand (Sandra); J. Bouma (Janneke); S. Bezemer (Sandra); P. Hermans (Pim); D. Wolvers (Danielle); K. Bellamy (Kate); L.G.J. Frenken (Leon); J. Gray (Jim); M. Iturriza-Gómara (Miren)

2012-01-01

textabstractRotavirus is the main cause of viral gastroenteritis in young children. Therefore, the development of inexpensive antiviral products for the prevention and/or treatment of rotavirus disease remains a priority. Previously we have shown that a recombinant monovalent antibody fragment
Potassium fluorotitanate preparation

International Nuclear Information System (INIS)

Perillo, Patricia; Ares, Osvaldo; Botbol, Jose.

1989-01-01

In order to determine the best conditions for potassium fluotitanate preparation as intermediate step in the electrolytic production of metalic titanium, the effects of a number of experimental variables have been studied. This method is a process of sintering titanium dioxide with potassium fluosilicate and potassium chloride, followed by leaching with boiling water and further crystallization by cooling the solution. An overall yield of 90% has been attained under the following conditions: working temperature: 750 deg C; heating time for sintering: 3 hours; molar ratio: titanium dioxide: potassium fluosilicate: potassium chloride: 1 : 2 : 0.4; number of leachings: 6. (Author) [es
Hyperfine-mediated static polarizabilities of monovalent atoms and ions

International Nuclear Information System (INIS)

Dzuba, V. A.; Flambaum, V. V.; Beloy, K.; Derevianko, A.

2010-01-01

We apply relativistic many-body methods to compute static differential polarizabilities for transitions inside the ground-state hyperfine manifolds of monovalent atoms and ions. Knowledge of this transition polarizability is required in a number of high-precision experiments, such as microwave atomic clocks and searches for CP-violating permanent electric dipole moments. While the traditional polarizability arises in the second order of interaction with the externally applied electric field, the differential polarizability involves an additional contribution from the hyperfine interaction of atomic electrons with nuclear moments. We derive formulas for the scalar and tensor polarizabilities including contributions from magnetic dipole and electric quadrupole hyperfine interactions. Numerical results are presented for Al, Rb, Cs, Yb + , Hg + , and Fr.
EVALUATION OF REACTOGENICITY, SAFETY AND IMMUNOGENICITY OF INACTIVATED MONOVALENT VACCINE IN CHILDREN

OpenAIRE

A.N. Mironov; A.A. Romanova; R.Ya. Meshkova; I.V. Fel’dblyum; N.V. Kupina; D.S. Bushmenkov; A.A. Tsaan

2010-01-01

NPO «Microgen» developed vaccine «PANDEFLU» — influenza inactivated subunit adsorbed monovalent vaccine, strain A/California/7/2009 (H1N1), for specific prophylaxis of pandemic influenza in different age groups of citizens. Reactogenicity, safety and immunogenicity were analyzed in a study of volunteers 18–60 years old. The article presents results of administration of vaccine «PANDEFLU» in children. The study performed in two clinical centers proves good tolerability, reactogenicity, safety ...
Comparison of modified Chicago sky blue stain and potassium hydroxide mount for the diagnosis of dermatomycoses and onychomycoses.

Science.gov (United States)

Liu, Zhong; Sheng, Ping; Yang, Yan-Ping; Li, Wen; Huang, Wen-Ming; Wang, Jie-Di; Fan, Yi-Ming

2015-05-01

The diagnostic value of modified Chicago sky blue (CSB) stain and potassium hydroxide (KOH) mount for superficial mycoses was compared using fungal culture as gold standard. The sensitivity and screening time of the CSB stain were superior to the KOH mount. The CBS stain is simple, quick and reliable for diagnosing superficial mycoses. Copyright © 2015. Published by Elsevier B.V.
Nanostructured gold and platinum electrodes on silicon structures for biosensing

International Nuclear Information System (INIS)

Ogurtsov, V I; Sheehan, M M

2005-01-01

Gold and platinum metal electrodes on Si/SiO 2 having undergone anisotropic potassium hydroxide (KOH) etch treatment are considered. This treatment etches at different rates and directions in the material resulting in creation of numerous pyramid shaped holes in the silicon substrate. This surface is used to make metal electrodes with increased electrode efficiency. The electrodes can serve as the sensors or as the sensor substrates (for surface polymer modification) and because both gold and platinum are inert they have applications for food safety biosensing. Wine, an economically significant food product, was chosen as a matrix, and impedance spectroscopy (EIS) was selected as a method of investigation of electrode behaviour. Based on results of EIS, different complexity equivalent circuits were determined by applying fitting mean square root optimisation of sensor complex impedance measurements
Graphene oxide and DNA aptamer based sub-nanomolar potassium detecting optical nanosensor

Science.gov (United States)

Datta, Debopam; Sarkar, Ketaki; Mukherjee, Souvik; Meshik, Xenia; Stroscio, Michael A.; Dutta, Mitra

2017-08-01

Quantum-dot (QD) based nanosensors are frequently used by researchers to detect small molecules, ions and different biomolecules. In this article, we present a sensor complex/system comprised of deoxyribonucleic acid (DNA) aptamer, gold nanoparticle and semiconductor QD, attached to a graphene oxide (GO) flake for detection of potassium. As reported herein, it is demonstrated that QD-aptamer-quencher nanosensor functions even when tethered to GO, opening the way to future applications where sensing can be accomplished simultaneously with other previously demonstrated applications of GO such as serving as a nanocarrier for drug delivery. Herein, it is demonstrated that the DNA based thrombin binding aptamer used in this study undergoes the conformational change needed for sensing even when the nanosensor complex is anchored to the GO. Analysis with the Hill equation indicates the interaction between aptamer and potassium follows sigmoidal Hill kinetics. It is found that the quenching efficiency of the optical sensor is linear with the logarithm of concentration from 1 pM to 100 nM and decreases for higher concentration due to unavailability of aptamer binding sites. Such a simple and sensitive optical aptasensor with minimum detection capability of 1.96 pM for potassium ion can also be employed in-vitro detection of different physiological ions, pathogens and disease detection methods.
Potassium toxicity at low serum potassium levels with refeeding syndrome.

Science.gov (United States)

Vemula, Praveen; Abela, Oliver G; Narisetty, Keerthy; Rhine, David; Abela, George S

2015-01-01

Refeeding syndrome is a life-threatening condition occurring in severely malnourished patients after initiating feeding. Severe hypophosphatemia with reduced adenosine triphosphate production has been implicated, but little data are available regarding electrolyte abnormalities. In this case, we report electrocardiographic changes consistent with hyperkalemia during potassium replacement after a serum level increase from 1.9 to 2.9 mEq/L. This was reversed by lowering serum potassium back to 2.0 mEq/L. In conclusion, the patient with prolonged malnutrition became adapted to low potassium levels and developed potassium toxicity with replacement. Copyright © 2015 Elsevier Inc. All rights reserved.
Uses of the potassium permanganate to eliminate copper cyanide from waste water resulting from a lixiviation plant in a gold mine (II): Pilot plant experiences; Aplicacion del permanganato potasico para la eliminacion de cianuros de cobre en aguas residuales de la planta de lixiviacion en una mina de oro (II): Ensayos en planta piloto

Energy Technology Data Exchange (ETDEWEB)

Sancho, J. P.; Fernandez, B.; Ayala, J.; Gracia, M. P.; Lavandeira, A.

2011-07-01

The search for a detoxification treatment of the wastewater generated during industrial processes, has been a constant for all companies in general and for gold mining in particular, whose wastewater generally contains high concentrations of cyanide compounds with high toxicity. In the previous research work, developed in the laboratory, the efficacy of potassium permanganate as an oxidizing agent for cyanidic wastewater, from a gold hydrometallurgical plant, has been demonstrated, achieving the destruction of copper cyanide complexes present in solution and the subsequent metal removal by precipitation as hydroxide. This paper presents the conclusions obtained after the implementation of the process developed in the laboratory, at pilot-plant scale. (Author) 30 refs.
Transient extracellular application of gold nanostars increases hippocampal neuronal activity.

Science.gov (United States)

Salinas, Kirstie; Kereselidze, Zurab; DeLuna, Frank; Peralta, Xomalin G; Santamaria, Fidel

2014-08-20

With the increased use of nanoparticles in biomedical applications there is a growing need to understand the effects that nanoparticles may have on cell function. Identifying these effects and understanding the mechanism through which nanoparticles interfere with the normal functioning of a cell is necessary for any therapeutic or diagnostic application. The aim of this study is to evaluate if gold nanoparticles can affect the normal function of neurons, namely their activity and coding properties. We synthesized star shaped gold nanoparticles of 180 nm average size. We applied the nanoparticles to acute mouse hippocampal slices while recording the action potentials from single neurons in the CA3 region. Our results show that CA3 hippocampal neurons increase their firing rate by 17% after the application of gold nanostars. The increase in excitability lasted for as much as 50 minutes after a transient 5 min application of the nanoparticles. Further analyses of the action potential shape and computational modeling suggest that nanoparticles block potassium channels responsible for the repolarization of the action potentials, thus allowing the cell to increase its firing rate. Our results show that gold nanoparticles can affect the coding properties of neurons by modifying their excitability.
Handling of potassium

International Nuclear Information System (INIS)

Schwarz, N.; Komurka, M.

1983-03-01

As a result for the Fast Breeder Development extensive experience is available worldwide with respect to Sodium technology. Due to the extension of the research program to topping cycles with Potassium as the working medium, test facilities with Potassium have been designed and operated in the Institute of Reactor Safety. The different chemical properties of Sodium and Potassium give rise in new safety concepts and operating procedures. The handling problems of Potassium are described in the light of theoretical properties and own experiences. Selected literature on main safety and operating problems complete this report. (Author) [de

The inhibitory effects of potassium chloride versus potassium silicate application on 137Cs uptake by rice

International Nuclear Information System (INIS)

Fujimura, Shigeto; Yoshioka, Kunio; Ota, Takeshi; Ishikawa, Tetsuya; Sato, Makoto; Satou, Mutsuto

2016-01-01

After the accident at the Fukushima Dai-ichi Nuclear Power Plant owned by the Tokyo Electric Power Company on 11 March 2011, potassium fertilizer was applied to agricultural fields in the southern Tohoku and northern Kanto regions of Japan to reduce the uptake of radiocesium by crops. In this study, we examined the effects of two types of potassium fertilizers, potassium chloride (a readily available potassium fertilizer) and potassium silicate (a slow-release potassium fertilizer), as well as a split application of potassium, on the accumulation of 137 Cs by rice plants in two pot experiments. The 137 Cs concentrations in the brown rice and in the above-ground plants were significantly lower after potassium chloride application than after potassium silicate application. The potassium ion (K + ) concentrations in soil solutions sampled 9 and 21 d after transplanting were significantly higher for the potassium chloride application than for the potassium silicate application. The K + concentrations in soil solutions observed in the application of potassium silicate were similar to those in the treatment when no potassium was applied. This finding indicates that the application of potassium silicate did not sufficiently increase the available K + for rice plants in the soil, which led to a greater uptake of 137 Cs after the potassium silicate application than after the application of potassium chloride. The 137 Cs concentration in brown rice was higher in the split application of potassium fertilizer with the second application at the full heading stage than that without split application and the split application with the second application before heading. - Highlights: • Potassium application reduced 137 Cs uptake by rice grown in pot experiments. • Readily available K fertilizer more effectively decreased brown rice 137 Cs concentration. • Potassium should be applied before heading to reduce brown rice 137 Cs concentration.
Competition among Li+, Na+, K+ and Rb+ Monovalent Ions for DNA in Molecular Dynamics Simulations using the Additive CHARMM36 and Drude Polarizable Force Fields

OpenAIRE

Savelyev, Alexey; MacKerell, Alexander D.

2015-01-01

In the present study we report on interactions of and competition between monovalent ions for two DNA sequences in MD simulations. Efforts included the development and validation of parameters for interactions among the first-group monovalent cations, Li+, Na+, K+ and Rb+, and DNA in the Drude polarizable and additive CHARMM36 force fields (FF). The optimization process targeted gas-phase QM interaction energies of various model compounds with ions and osmotic pressures of bulk electrolyte so...
The inhibitory effects of potassium chloride versus potassium silicate application on (137)Cs uptake by rice.

Science.gov (United States)

Fujimura, Shigeto; Yoshioka, Kunio; Ota, Takeshi; Ishikawa, Tetsuya; Sato, Makoto; Satou, Mutsuto

2016-03-01

After the accident at the Fukushima Dai-ichi Nuclear Power Plant owned by the Tokyo Electric Power Company on 11 March 2011, potassium fertilizer was applied to agricultural fields in the southern Tohoku and northern Kanto regions of Japan to reduce the uptake of radiocesium by crops. In this study, we examined the effects of two types of potassium fertilizers, potassium chloride (a readily available potassium fertilizer) and potassium silicate (a slow-release potassium fertilizer), as well as a split application of potassium, on the accumulation of (137)Cs by rice plants in two pot experiments. The (137)Cs concentrations in the brown rice and in the above-ground plants were significantly lower after potassium chloride application than after potassium silicate application. The potassium ion (K(+)) concentrations in soil solutions sampled 9 and 21 d after transplanting were significantly higher for the potassium chloride application than for the potassium silicate application. The K(+) concentrations in soil solutions observed in the application of potassium silicate were similar to those in the treatment when no potassium was applied. This finding indicates that the application of potassium silicate did not sufficiently increase the available K(+) for rice plants in the soil, which led to a greater uptake of (137)Cs after the potassium silicate application than after the application of potassium chloride. The (137)Cs concentration in brown rice was higher in the split application of potassium fertilizer with the second application at the full heading stage than that without split application and the split application with the second application before heading. Copyright © 2016 Elsevier Ltd. All rights reserved.
Influence of the synthesis conditions of gold nanoparticles on the structure and architectonics of dipeptide composites

Energy Technology Data Exchange (ETDEWEB)

Loskutov, Alexander I., E-mail: ailoskutov@yandex.ru [Moscow State Technological University STANKIN (Russian Federation); Guskova, Olga A. [Leibniz Institute of Polymer Research Dresden (Germany); Grigoriev, Sergey N.; Oshurko, Vadim B. [Moscow State Technological University STANKIN (Russian Federation); Tarasiuk, Aleksei V. [Russian Academy of Medical Sciences, FSBI “Zakusov Institute of Pharmacology” (Russian Federation); Uryupina, Olga Ya. [Russian Academy of Sciences, Frumkin Institute of Physical Chemistry and Electrochemistry (Russian Federation)

2016-08-15

A wide variety of peptides and their natural ability to self-assemble makes them very promising candidates for the fabrication of solid-state devices based on nano- and mesocrystals. In this work, we demonstrate an approach to form peptide composite layers with gold nanoparticles through in situ reduction of chloroauric acid trihydrate by dipeptide and/or dipeptide/formaldehyde mixture in the presence of potassium carbonate at different ratios of components. Appropriate composition of components for the synthesis of highly stable gold colloidal dispersion with particle size of 34–36 nm in dipeptide/formaldehyde solution is formulated. Infrared spectroscopy results indicate that dipeptide participates in the reduction process, conjugation with gold nanoparticles and the self-assembly in 2D, which accompanied by changing peptide chain conformations. The structure and morphology of the peptide composite solid layers with gold nanoparticles on gold, mica and silica surfaces are characterized by atomic force microscopy. In these experiments, the flat particles, dendrites, chains, mesocrystals and Janus particles are observed depending on the solution composition and the substrate/interface used. The latter aspect is studied on the molecular level using computer simulations of individual peptide chains on gold, mica and silica surfaces.
Oral potassium supplementation in surgical patients.

Science.gov (United States)

Hainsworth, Alison J; Gatenby, Piers A

2008-08-01

Hospital inpatients are frequently hypokalaemic. Low plasma potassium levels may cause life threatening complications, such as cardiac arrhythmias. Potassium supplementation may be administered parenterally or enterally. Oral potassium supplements have been associated with oesophageal ulceration, strictures and gastritis. An alternative to potassium salt tablets or solution is dietary modification with potassium rich food stuffs, which has been proven to be a safe and effective method for potassium supplementation. The potassium content of one medium banana is equivalent to a 12 mmol potassium salt tablet. Potassium supplementation by dietary modification has been shown to be equally efficacious to oral potassium salt supplementation and is preferred by the majority of patients. Subsequently, it is our practice to replace potassium using dietary modification, particularly in surgical patients having undergone oesophagogastrectomy or in those with peptic ulcer disease.
Ion Transport across Biological Membranes by Carborane-Capped Gold Nanoparticles.

Science.gov (United States)

Grzelczak, Marcin P; Danks, Stephen P; Klipp, Robert C; Belic, Domagoj; Zaulet, Adnana; Kunstmann-Olsen, Casper; Bradley, Dan F; Tsukuda, Tatsuya; Viñas, Clara; Teixidor, Francesc; Abramson, Jonathan J; Brust, Mathias

2017-12-26

Carborane-capped gold nanoparticles (Au/carborane NPs, 2-3 nm) can act as artificial ion transporters across biological membranes. The particles themselves are large hydrophobic anions that have the ability to disperse in aqueous media and to partition over both sides of a phospholipid bilayer membrane. Their presence therefore causes a membrane potential that is determined by the relative concentrations of particles on each side of the membrane according to the Nernst equation. The particles tend to adsorb to both sides of the membrane and can flip across if changes in membrane potential require their repartitioning. Such changes can be made either with a potentiostat in an electrochemical cell or by competition with another partitioning ion, for example, potassium in the presence of its specific transporter valinomycin. Carborane-capped gold nanoparticles have a ligand shell full of voids, which stem from the packing of near spherical ligands on a near spherical metal core. These voids are normally filled with sodium or potassium ions, and the charge is overcompensated by excess electrons in the metal core. The anionic particles are therefore able to take up and release a certain payload of cations and to adjust their net charge accordingly. It is demonstrated by potential-dependent fluorescence spectroscopy that polarized phospholipid membranes of vesicles can be depolarized by ion transport mediated by the particles. It is also shown that the particles act as alkali-ion-specific transporters across free-standing membranes under potentiostatic control. Magnesium ions are not transported.
KV7 potassium channels

DEFF Research Database (Denmark)

Stott, Jennifer B; Jepps, Thomas Andrew; Greenwood, Iain A

2014-01-01

Potassium channels are key regulators of smooth muscle tone, with increases in activity resulting in hyperpolarisation of the cell membrane, which acts to oppose vasoconstriction. Several potassium channels exist within smooth muscle, but the KV7 family of voltage-gated potassium channels have been...
Chronic potassium depletion increases adrenal progesterone production that is necessary for efficient renal retention of potassium.

Science.gov (United States)

Elabida, Boutaïna; Edwards, Aurélie; Salhi, Amel; Azroyan, Anie; Fodstad, Heidi; Meneton, Pierre; Doucet, Alain; Bloch-Faure, May; Crambert, Gilles

2011-08-01

Modern dietary habits are characterized by high-sodium and low-potassium intakes, each of which was correlated with a higher risk for hypertension. In this study, we examined whether long-term variations in the intake of sodium and potassium induce lasting changes in the plasma concentration of circulating steroids by developing a mathematical model of steroidogenesis in mice. One finding of this model was that mice increase their plasma progesterone levels specifically in response to potassium depletion. This prediction was confirmed by measurements in both male mice and men. Further investigation showed that progesterone regulates renal potassium handling both in males and females under potassium restriction, independent of its role in reproduction. The increase in progesterone production by male mice was time dependent and correlated with decreased urinary potassium content. The progesterone-dependent ability to efficiently retain potassium was because of an RU486 (a progesterone receptor antagonist)-sensitive stimulation of the colonic hydrogen, potassium-ATPase (known as the non-gastric or hydrogen, potassium-ATPase type 2) in the kidney. Thus, in males, a specific progesterone concentration profile induced by chronic potassium restriction regulates potassium balance.
Penicillin V Potassium

Science.gov (United States)

Penicillin V potassium is used to treat certain infections caused by bacteria such as pneumonia and other ... heart valves and other symptoms) from coming back. Penicillin V potassium is in a class of medications ...
Evaluation of the potassium adsorption capacity of a potassium adsorption filter during rapid blood transfusion.

Science.gov (United States)

Matsuura, H; Akatsuka, Y; Muramatsu, C; Isogai, S; Sugiura, Y; Arakawa, S; Murayama, M; Kurahashi, M; Takasuga, H; Oshige, T; Yuba, T; Mizuta, S; Emi, N

2015-05-01

The concentration of extracellular potassium in red blood cell concentrates (RCCs) increases during storage, leading to risk of hyperkalemia. A potassium adsorption filter (PAF) can eliminate the potassium at normal blood transfusion. This study aimed to investigate the potassium adsorption capacity of a PAF during rapid blood transfusion. We tested several different potassium concentrations under a rapid transfusion condition using a pressure bag. The adsorption rates of the 70-mEq/l model were 76·8%. The PAF showed good potassium adsorption capacity, suggesting that this filter may provide a convenient method to prevent hyperkalemia during rapid blood transfusion. © 2015 International Society of Blood Transfusion.
Potassium maldistribution revisited

African Journals Online (AJOL)

Background:This study investigated maldistribution of concentrated 15% potassium chloride after injection into .... and latter experiments referred to for example as “Control 1” ..... be further investigated as a reliable, simple method of potassium.
21 CFR 184.1619 - Potassium carbonate.

Science.gov (United States)

2010-04-01

... solution of potassium hydroxide with excess carbon dioxide to produce potassium carbonate; (3) By treating a solution of potassium hydroxide with carbon dioxide to produce potassium bicarbonate, which is... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium carbonate. 184.1619 Section 184.1619 Food...
Yeast Kch1 and Kch2 membrane proteins play a pleiotropic role in membrane potential establishment and monovalent cation homeostasis regulation.

Science.gov (United States)

Felcmanova, Kristina; Neveceralova, Petra; Sychrova, Hana; Zimmermannova, Olga

2017-08-01

The Kch1 and Kch2 plasma-membrane proteins were identified in Saccharomyces cerevisiae as being essential for the activation of a high-affinity Ca2+ influx system. We searched for Kch proteins roles in the maintenance of cation homeostasis and tested the effect of kch1 and/or kch2 deletions on various physiological parameters. Compared to wild-type, kch1 kch2 mutant cells were smaller, relatively hyperpolarised, grew better under limited K+ conditions and exhibited altered growth in the presence of monovalent cations. The absence of Kch1 and Kch2 did not change the intracellular pH in cells growing at low potassium or the tolerance of cells to divalent cations, high concentration of sorbitol or extreme external pH. The overexpression of KCH1 only increased the intracellular pH in the presence of elevated K+ in media. None of the phenotypes associated with the deletion of KCH1 and KCH2 in wild type were observed in a strain lacking KCH genes and main K+ uptake systems Trk1 and Trk2. The role of the Kch homologue in cation homeostasis was also tested in Candida albicans cells. Our data demonstrate that Kch proteins significantly contribute to the maintenance of optimal cation homeostasis and membrane potential in S. cerevisiae but not in C. albicans. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Potassium supplements for oral diarrhoea regimens.

Science.gov (United States)

Clements, M L; Levine, M M; Black, R E; Hughes, T P; Rust, J; Tome, F C

1980-10-18

A study is proposed for supplementing potassium loss from diarrhea in rehydration therapies with fresh fruit and other naturally potassium-rich foods. Bananas contain .1 mol of potassium per gm. Freshly squeezed lemon or orange juices were tested for potassium and sodium content and found to have very low potassium concentration. Therefore, the banana was chosen for an upcoming study that will determine if infants and children suffering from diarrhea can ingest the amounts of the fruit necessary to elevate the potassium level sufficiently. Bananas as the potassium source are thought to be well-accepted in developing areas.
Potassium adsorption ratios as an indicator for the fate of agricultural potassium in groundwater

NARCIS (Netherlands)

Griffioen, J.

2001-01-01

Fertilization of agricultural land in groundwater infiltration areas often causes deterioration of groundwater quality. In addition to nitrogen and phosphorous, potassium deserves attention. The fate of potassium in the subsurface is controlled mainly by cation-exchange. Use of the Potassium
Potassium in milk and milk products

International Nuclear Information System (INIS)

Sombrito, E.Z.; Nuguid, Z.F.S.; Tangonan, M.C.

1989-01-01

The amount of potassium in imported processed milk was determined by gamma spectral analysis. The results show that the potassium content of diluted infant formula milk is closest to the reported mean concentration of potassium in human milk while other milk types have potassium values similar to the potassium content of cow milk. (Auth.). 2 figs., 5 refs
Effect of polacrilin potassium as disintegrant on bioavailability of diclofenac potassium in tablets : a technical note.

Science.gov (United States)

Bele, Mrudula H; Derle, Diliprao V

2012-09-01

Polacrilin potassium is an ion exchange resin used in oral pharmaceutical formulations as a tablet disintegrant. It is a weakly acidic cation exchange resin. Chemically, it is a partial potassium salt of a copolymer of methacrylic acid with divinyl benzene. It ionizes to an anionic polymer chain and potassium cations. It was hypothesized that polacrilin potassium may be able to improve the permeability of anionic drugs according to the Donnan membrane phenomenon. The effect of polacrilin potassium on the permeability of diclofenac potassium, used as a model anionic drug, was tested in vitro using diffusion cells and in vivo by monitoring serum levels in rats. The amount of drug permeated across a dialysis membrane in vitro was significantly more in the presence of polacrilin potassium. Significant improvement was found in the extent of drug absorption in vivo. It could be concluded that polacrilin potassium may be used as a high-functionality excipient for improving the bioavailability of anionic drugs having poor gastrointestinal permeability.
21 CFR 184.1625 - Potassium citrate.

Science.gov (United States)

2010-04-01

... acid with potassium hydroxide or potassium carbonate. It occurs as transparent crystals or a white... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium citrate. 184.1625 Section 184.1625 Food... Specific Substances Affirmed as GRAS § 184.1625 Potassium citrate. (a) Potassium citrate (C6H5K3O7·H2O, CAS...
Gold film with gold nitride - A conductor but harder than gold

International Nuclear Information System (INIS)

Siller, L.; Peltekis, N.; Krishnamurthy, S.; Chao, Y.; Bull, S.J.; Hunt, M.R.C.

2005-01-01

The formation of surface nitrides on gold films is a particularly attractive proposition, addressing the need to produce harder, but still conductive, gold coatings which reduce wear but avoid the pollution associated with conventional additives. Here we report production of large area gold nitride films on silicon substrates, using reactive ion sputtering and plasma etching, without the need for ultrahigh vacuum. Nanoindentation data show that gold nitride films have a hardness ∼50% greater than that of pure gold. These results are important for large-scale applications of gold nitride in coatings and electronics
Monovalent cation and amiloride analog modulation of adrenergic ligand binding to the unglycosylated alpha 2B-adrenergic receptor subtype

International Nuclear Information System (INIS)

Wilson, A.L.; Seibert, K.; Brandon, S.; Cragoe, E.J. Jr.; Limbird, L.E.

1991-01-01

The unglycosylated alpha 2B subtype of the alpha 2-adrenergic receptor found in NG-108-15 cells possesses allosteric regulation of adrenergic ligand binding by monovalent cations and 5-amino-substituted amiloride analogs. These findings demonstrate that allosteric modulation of adrenergic ligand binding is not a property unique to the alpha 2A subtype. The observation that amiloride analogs as well as monovalent cations can modulate adrenergic ligand binding to the nonglycosylated alpha 2B subtype indicates that charge shielding due to carbohydrate moieties does not play a role in this allosteric modulation but, rather, these regulatory effects result from interactions of cations and amiloride analogs with the protein moiety of the receptor. Furthermore, the observation that both alpha 2A and alpha 2B receptor subtypes are modulated by amiloride analogs suggests that structural domains that are conserved between the two are likely to be involved in this allosteric modulation

Potassium and Your CKD Diet

Science.gov (United States)

... vegetable in your diet, leach them before using. Leaching is a process by which some potassium can be pulled out ... out of my favorite high-potassium vegetables? The process of leaching will help pull potassium out of some high- ...
Obtaining of potassium dicyan-argentate

International Nuclear Information System (INIS)

Sattarova, M.A.; Solojenkin, P.M.

1997-01-01

This work is devoted to obtaining of potassium dicyan-argentate. By means of exchange reaction between silver nitrate and potassium cyanide the potassium dicyan-argentate was synthesized. The analysis of obtained samples was carried out by means of titration and potentiometry.
Extrarenal potassium adaptation: role of skeletal muscle

International Nuclear Information System (INIS)

Blachley, J.D.; Crider, B.P.; Johnson, J.H.

1986-01-01

Following the ingestion of a high-potassium-content diet for only a few days, the plasma potassium of rats rises only modestly in response to a previously lethal dose of potassium salts. This acquired tolerance, termed potassium adaptation, is principally the result of increased capacity to excrete potassium into the urine. However, a substantial portion of the acute potassium dose is not immediately excreted and is apparently translocated into cells. Previous studies have failed to show an increase in the content of potassium of a variety of tissues from such animals. Using 86 Rb as a potassium analogue, we have shown that the skeletal muscle of potassium-adapted rats takes up significantly greater amounts of potassium in vivo in response to an acute challenge than does that of control animals. Furthermore, the same animals exhibit greater efflux of 86 Rb following the termination of the acute infusion. We have also shown that the Na+-K+-ATPase activity and ouabain-binding capacity of skeletal muscle microsomes are increased by the process of potassium adaptation. We conclude that skeletal muscle is an important participant in potassium adaptation and acts to temporarily buffer acute increases in the extracellular concentration of potassium
Attractive non-DLVO forces induced by adsorption of monovalent organic ions.

Science.gov (United States)

Smith, Alexander M; Maroni, Plinio; Borkovec, Michal

2017-12-20

Direct force measurements between negatively charged colloidal particles were carried out using an atomic force microscope (AFM) in aqueous solutions containing monovalent organic cations, namely tetraphenylarsonium (Ph 4 As + ), 1-hexyl-3-methylimidazolium (HMIM + ), and 1-octyl-3-methylimidazolium (OMIM + ). These ions adsorb to the particle surface, and induce a charge reversal. The forces become attractive at the charge neutralization point, but they are stronger than van der Waals forces. This additional and unexpected attraction decays exponentially with a decay length of a few nanometers, and is strikingly similar to the one previously observed in the presence of multivalent ions. This attractive force probably originates from coupled spontaneous charge fluctuations on the respective surfaces as initially suggested by Kirkwood and Shumaker.
21 CFR 184.1631 - Potassium hydroxide.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium hydroxide. 184.1631 Section 184.1631 Food... Specific Substances Affirmed as GRAS § 184.1631 Potassium hydroxide. (a) Potassium hydroxide (KOH, CAS Reg... pellets, flakes, sticks, lumps, and powders. Potassium hydroxide is obtained commercially from the...
Determination of gold in gold ores

International Nuclear Information System (INIS)

Keedy, C.R.; Parson, L.; Shen, J.

1989-01-01

The gold content of placer gold flakes and gold bearing ores was determined by instrumental and radiochemical neutron activation analysis, respectively. It was discovered that significant errors result in the instrumental method for gold flakes as small as 10 mg due to sample self-absorption of neutrons during irradiation. Reliable results were obtained for both ore samples and gold flakes by dissolving the samples in aqua regia prior to irradiation. (author) 7 refs.; 3 tabs
21 CFR 184.1622 - Potassium chloride.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium chloride. 184.1622 Section 184.1622 Food... Specific Substances Affirmed as GRAS § 184.1622 Potassium chloride. (a) Potassium chloride (KCl, CAS Reg... levels not to exceed current good manufacturing practice. Potassium chloride may be used in infant...
Competition among Li+, Na+, K+ and Rb+ Monovalent Ions for DNA in Molecular Dynamics Simulations using the Additive CHARMM36 and Drude Polarizable Force Fields

Science.gov (United States)

Savelyev, Alexey; MacKerell, Alexander D.

2015-01-01

In the present study we report on interactions of and competition between monovalent ions for two DNA sequences in MD simulations. Efforts included the development and validation of parameters for interactions among the first-group monovalent cations, Li+, Na+, K+ and Rb+, and DNA in the Drude polarizable and additive CHARMM36 force fields (FF). The optimization process targeted gas-phase QM interaction energies of various model compounds with ions and osmotic pressures of bulk electrolyte solutions of chemically relevant ions. The optimized ionic parameters are validated against counterion condensation theory and buffer exchange-atomic emission spectroscopy measurements providing quantitative data on the competitive association of different monovalent ions with DNA. Comparison between experimental and MD simulation results demonstrates that, compared to the additive CHARMM36 model, the Drude FF provides an improved description of the general features of the ionic atmosphere around DNA and leads to closer agreement with experiment on the ionic competition within the ion atmosphere. Results indicate the importance of extended simulation systems on the order of 25 Å beyond the DNA surface to obtain proper convergence of ion distributions. PMID:25751286
In silico prediction of monovalent and chimeric tetravalent vaccines for prevention and treatment of dengue fever.

Science.gov (United States)

Vijayakumar, Subramaniyan; Ramesh, Venkatachalam; Prabhu, Srinivasan; Manogar, Palani

2017-11-01

Reverse vaccinology method was used to predict the monovalent peptide vaccine candidate to produce antibodies for therapeutic purpose and to predict tetravalent vaccine candidate to act as a common vaccine to cover all the fever dengue virus serotypes. Envelope (E)-proteins of DENV-1-4 serotypes were used for vaccine prediction using NCBI, Uniprot/Swissprot, Swiss-prot viewer, VaxiJen V2.0, TMHMM, BCPREDS, Propred-1, Propred and MHC Pred,. E-proteins of DENV-1-4 serotypes were identified as antigen from which T cell epitopes, through B cell epitopes, were predicted to act as peptide vaccine candidates. Each selected T cell epitope of E-protein was confirmed to act as vaccine and to induce complementary antibody against particular serotype of dengue virus. Chimeric tetravalent vaccine was formed by the conjugation of four vaccines, each from four dengue serotypes to act as a common vaccine candidate for all the four dengue serotypes. It can be justifiably concluded that the monovalent 9-mer T cell epitope for each DENV serotypes can be used to produce specific antibody agaomst dengue virus and a chimeric common tetravalent vaccine candidate to yield a comparative vaccine to cover any of the four dengue virus serotype. This vaccine is expected to act as highly immunogenic against preventing dengue fever.
21 CFR 184.1643 - Potassium sulfate.

Science.gov (United States)

2010-04-01

... hydroxide or potassium carbonate. (b) The ingredient meets the specifications of the “Food Chemicals Codex... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium sulfate. 184.1643 Section 184.1643 Food... Specific Substances Affirmed as GRAS § 184.1643 Potassium sulfate. (a) Potassium sulfate (K2SO4, CAS Reg...
EVALUATION OF REACTOGENICITY, SAFETY AND IMMUNOGENICITY OF INACTIVATED MONOVALENT VACCINE IN CHILDREN

Directory of Open Access Journals (Sweden)

A.N. Mironov

2010-01-01

Full Text Available NPO «Microgen» developed vaccine «PANDEFLU» — influenza inactivated subunit adsorbed monovalent vaccine, strain A/California/7/2009 (H1N1, for specific prophylaxis of pandemic influenza in different age groups of citizens. Reactogenicity, safety and immunogenicity were analyzed in a study of volunteers 18–60 years old. The article presents results of administration of vaccine «PANDEFLU» in children. The study performed in two clinical centers proves good tolerability, reactogenicity, safety and high immunogenicity of this vaccine.Key words: children, influenza, influenza virus А/H1N1, inactivated influenza vaccine, reactogenicity, safety, immunogenicity.(Voprosy sovremennoi pediatrii — Current Pediatrics. – 2010;9(4:106-109
Contribution to the physicochemical investigation of monovalent thallium and tetravalent uranium fluorides

International Nuclear Information System (INIS)

Hsini, M.S.

1983-07-01

Ionic transport properties are studied in monovalent elements and tetravalent uranium fluorides and oxyfluorides. Crystal structure of the oxyfluoride: TlUsub(2.75)OF 10 was determined by X-ray diffraction on a monocrystal. The particular role played by oxygen is evidenced in the stabilization of the crystal structure based on an original arrangement of Archimedes antiprisms: UOF 7 corresponding to a long distance order oxygen-fluorine in the anionic network. Electric conductivity measurements in AC by the complex impedance method or in DC by the Van der Pauw method allowed performance estimation of these materials which are solid electrolytes. Correlations between electrical properties and structure give information in basic diffusion mechanism in these materials [fr
Potassium channels in brain mitochondria.

Science.gov (United States)

Bednarczyk, Piotr

2009-01-01

Potassium channels are the most widely distributed class of ion channels. These channels are transmembrane proteins known to play important roles in both normal and pathophysiological functions in all cell types. Various potassium channels are recognised as potential therapeutic targets in the treatment of Parkinson's disease, Alzheimer's disease, brain/spinal cord ischaemia and sepsis. In addition to their importance as therapeutic targets, certain potassium channels are known for their beneficial roles in anaesthesia, cardioprotection and neuroprotection. Some types of potassium channels present in the plasma membrane of various cells have been found in the inner mitochondrial membrane as well. Potassium channels have been proposed to regulate mitochondrial membrane potential, respiration, matrix volume and Ca(+) ion homeostasis. It has been proposed that mitochondrial potassium channels mediate ischaemic preconditioning in various tissues. However, the specificity of a pharmacological agents and the mechanisms underlying their effects on ischaemic preconditioning remain controversial. The following potassium channels from various tissues have been identified in the inner mitochondrial membrane: ATP-regulated (mitoK(ATP)) channel, large conductance Ca(2+)-regulated (mitoBK(Ca)) channel, intermediate conductance Ca(2+)-regulated (mitoIK(Ca)) channel, voltage-gated (mitoKv1.3 type) channel, and twin-pore domain (mitoTASK-3) channel. It has been shown that increased potassium flux into brain mitochondria induced by either the mitoK(ATP) channel or mitoBK(Ca) channel affects the beneficial effects on neuronal cell survival under pathological conditions. Recently, differential distribution of mitoBK(Ca) channels has been observed in neuronal mitochondria. These findings may suggest a neuroprotective role for the mitoBK(Ca) channel in specific brain structures. This minireview summarises current data on brain mitochondrial potassium channels and the efforts to identify
On the use of dimensionless parameters in acid-base theory: VI. The buffer capacities of equimolar binary mixtures of monovalent weak protolytes as compared to that of bivalent protolytes.

Science.gov (United States)

Rilbe, H

1994-05-01

The general equation for the relative molar buffer capacity, earlier shown to be valid for bivalent acids, bases, and ampholytes, is shown to hold also for equimolar, binary mixtures of monovalent protolytes if only the parameter s = square root of K1'/4K2' is exchanged for t = s + 1/4s. The same applies to the equations for the mean valence of the two classes of protolytes. As a consequence thereof, the titration and buffer capacity curves of a bivalent protolyte are identical with those of a monovalent protolyte with a pK' value equal to the with those of a monovalent protolyte with a pK' value equal to square root of K1'K2' of the bivalent one (the isoprotic point of an ampholyte). For a hypothetical bivalent acid, base, or ampholyte with s = 1, delta pK' = log 4, this implies that the intrinsic rather than the hybrid dissociation constants are responsible for the titration and buffer capacity curves.
The heart and potassium: a banana republic.

Science.gov (United States)

Khan, Ehsan; Spiers, Christine; Khan, Maria

2013-03-01

The importance of potassium in maintaining stable cardiac function is a clinically understood phenomenon. Physiologically the importance of potassium in cardiac function is described by the large number of different kinds of potassium ions channels found in the heart compared to channels and membrane transport mechanisms for other ions such as sodium and calcium. Potassium is important in physiological homeostatic control of cardiac function, but is also of relevance to the diseased state, as potassium-related effects may stabilize or destabilize cardiac function. This article aims to provide a detailed understanding of potassium-mediated cardiac function. This will help the clinical practitioner evaluate how modulation of potassium ion channels by disease and pharmacological manipulation affect the cardiac patient, thus aiding in decision making when faced with clinical problems related to potassium.
In-vitro Neurotoxicity of Two Malaysian Krait Species (Bungarus candidus and Bungarus fasciatus Venoms: Neutralization by Monovalent and Polyvalent Antivenoms from Thailand

Directory of Open Access Journals (Sweden)

Muhamad Rusdi Ahmad Rusmili

2014-03-01

Full Text Available Bungarus candidus and Bungarus fasciatus are two species of krait found in Southeast Asia. Envenoming by these snakes is often characterized by neurotoxicity and, without treatment, causes considerable morbidity and mortality. In this study, the in vitro neurotoxicity of each species, and the effectiveness of two monovalent antivenoms and a polyvalent antivenom, against the neurotoxic effects of the venoms, were examined in a skeletal muscle preparation. Both venoms caused concentration-dependent inhibition of indirect twitches, and attenuated responses to exogenous nicotinic receptor agonists, in the chick biventer preparation, with B. candidus venom being more potent than B. fasciatus venom. SDS-PAGE and western blot analysis indicated different profiles between the venoms. Despite these differences, most proteins bands were recognized by all three antivenoms. Antivenom, added prior to the venoms, attenuated the neurotoxic effect of the venoms. Interestingly, the respective monovalent antivenoms did not neutralize the effects of the venom from the other Bungarus species indicating a relative absence of cross-neutralization. Addition of a high concentration of polyvalent antivenom, at the t90 time point after addition of venom, partially reversed the neurotoxicity of B. fasciatus venom but not B. candidus venom. The monovalent antivenoms had no significant effect when added at the t90 time point. This study showed that B. candidus and B. fasciatus venoms display marked in vitro neurotoxicity in the chick biventer preparation and administration of antivenoms at high dose is necessary to prevent or reverse neurotoxicity.
Chemisorption of iodine-125 to gold nanoparticles allows for real-time quantitation and potential use in nanomedicine

Energy Technology Data Exchange (ETDEWEB)

Walsh, Adrian A, E-mail: a.walsh@nanobiosols.com [Liverpool Science Park, Nano Biosols Ltd (United Kingdom)

2017-04-15

Gold nanoparticles have been available for many years as a research tool in the life sciences due to their electron density and optical properties. New applications are continually being developed, particularly in nanomedicine. One drawback is the need for an easy, real-time quantitation method for gold nanoparticles so that the effects observed in in vitro cell toxicity assays and cell uptake studies can be interpreted quantitatively in terms of nanoparticle loading. One potential method of quantifying gold nanoparticles in real time is by chemisorption of iodine-125, a gamma emitter, to the nanoparticles. This paper revisits the labelling of gold nanoparticles with iodine-125, first described 30 years ago and never fully exploited since. We explore the chemical properties and usefulness in quantifying bio-functionalised gold nanoparticle binding in a quick and simple manner. The gold particles were labelled specifically and quantitatively simply by mixing the two items. The nature of the labelling is chemisorption and is robust, remaining bound over several weeks in a variety of cell culture media. Chemisorption was confirmed as potassium iodide can remove the label whereas sodium chloride and many other buffers had no effect. Particles precoated in polymers or proteins can be labelled just as efficiently allowing for post-labelling experiments in situ rather than using radioactive gold atoms in the production process. We also demonstrate that interparticle exchange of I-125 between different size particles does not appear to take place confirming the affinity of the binding.
Chemisorption of iodine-125 to gold nanoparticles allows for real-time quantitation and potential use in nanomedicine

Science.gov (United States)

Walsh, Adrian A.

2017-04-01

Gold nanoparticles have been available for many years as a research tool in the life sciences due to their electron density and optical properties. New applications are continually being developed, particularly in nanomedicine. One drawback is the need for an easy, real-time quantitation method for gold nanoparticles so that the effects observed in in vitro cell toxicity assays and cell uptake studies can be interpreted quantitatively in terms of nanoparticle loading. One potential method of quantifying gold nanoparticles in real time is by chemisorption of iodine-125, a gamma emitter, to the nanoparticles. This paper revisits the labelling of gold nanoparticles with iodine-125, first described 30 years ago and never fully exploited since. We explore the chemical properties and usefulness in quantifying bio-functionalised gold nanoparticle binding in a quick and simple manner. The gold particles were labelled specifically and quantitatively simply by mixing the two items. The nature of the labelling is chemisorption and is robust, remaining bound over several weeks in a variety of cell culture media. Chemisorption was confirmed as potassium iodide can remove the label whereas sodium chloride and many other buffers had no effect. Particles precoated in polymers or proteins can be labelled just as efficiently allowing for post-labelling experiments in situ rather than using radioactive gold atoms in the production process. We also demonstrate that interparticle exchange of I-125 between different size particles does not appear to take place confirming the affinity of the binding.
Chemisorption of iodine-125 to gold nanoparticles allows for real-time quantitation and potential use in nanomedicine

International Nuclear Information System (INIS)

Walsh, Adrian A

2017-01-01

Gold nanoparticles have been available for many years as a research tool in the life sciences due to their electron density and optical properties. New applications are continually being developed, particularly in nanomedicine. One drawback is the need for an easy, real-time quantitation method for gold nanoparticles so that the effects observed in in vitro cell toxicity assays and cell uptake studies can be interpreted quantitatively in terms of nanoparticle loading. One potential method of quantifying gold nanoparticles in real time is by chemisorption of iodine-125, a gamma emitter, to the nanoparticles. This paper revisits the labelling of gold nanoparticles with iodine-125, first described 30 years ago and never fully exploited since. We explore the chemical properties and usefulness in quantifying bio-functionalised gold nanoparticle binding in a quick and simple manner. The gold particles were labelled specifically and quantitatively simply by mixing the two items. The nature of the labelling is chemisorption and is robust, remaining bound over several weeks in a variety of cell culture media. Chemisorption was confirmed as potassium iodide can remove the label whereas sodium chloride and many other buffers had no effect. Particles precoated in polymers or proteins can be labelled just as efficiently allowing for post-labelling experiments in situ rather than using radioactive gold atoms in the production process. We also demonstrate that interparticle exchange of I-125 between different size particles does not appear to take place confirming the affinity of the binding.
Increased serum potassium affects renal outcomes

DEFF Research Database (Denmark)

Miao, Y; Dobre, D; Heerspink, H J Lambers

2011-01-01

To assess the effect of an angiotensin receptor blocker (ARB) on serum potassium and the effect of a serum potassium change on renal outcomes in patients with type 2 diabetes and nephropathy.......To assess the effect of an angiotensin receptor blocker (ARB) on serum potassium and the effect of a serum potassium change on renal outcomes in patients with type 2 diabetes and nephropathy....

Can Diuretics Decrease Your Potassium Level?

Science.gov (United States)

... of low potassium? Can diuretics decrease your potassium level? Answers from Sheldon G. Sheps, M.D. Yes, ... your urine. This can lead to low potassium levels in your blood (hypokalemia). Signs and symptoms of ...
Biosynthesis of gold nanoparticles using diatoms-silica-gold and EPS-gold bionanocomposite formation

OpenAIRE

Schröfel, Adam; Kratošová, Gabriela; Bohunická, Markéta; Dobročka, Edmund; Vávra, Ivo

2011-01-01

Novel synthesis of gold nanoparticles, EPS-gold, and silica-gold bionanocomposites by biologically driven processes employing two diatom strains (Navicula atomus, Diadesmis gallica) is described. Transmission electron microscopy (TEM) and electron diffraction analysis (SAED) revealed a presence of gold nanoparticles in the experimental solutions of the diatom culture mixed with tetrachloroaureate. Nature of the gold nanoparticles was confirmed by X-ray diffraction studies. Scanning electron m...
Preparation of potassium-reduced tantalum powders

International Nuclear Information System (INIS)

Kolosov, V.N.; Miroshnichenko, M.N.; Orlov, V.M.; Prokhorova, T.Yu.

2005-01-01

Characteristics of tantalum powders prepared by reduction of molten potassium heptafluorotantalate with liquid potassium are studied in a temperature range of 750 - 850 deg C using potassium chloride as a flux at a ratio of K 2 TaF 7 : KCl = 1, 2, and 3. The use of potassium as a reducing agent facilitates washing of tantalum powders for impurity salt removal, reduces sodium content and leakage currents in the anodes. As compared to sodium process, the potassium reduction results in a high yield of sponge material, a decrease in the specific surface area and yield of tantalum powder suitable for manufacture of capacitor anodes [ru
Ultra-long-term human salt balance studies reveal interrelations between sodium, potassium, and chloride intake and excretion.

Science.gov (United States)

Birukov, Anna; Rakova, Natalia; Lerchl, Kathrin; Engberink, Rik Hg Olde; Johannes, Bernd; Wabel, Peter; Moissl, Ulrich; Rauh, Manfred; Luft, Friedrich C; Titze, Jens

2016-07-01

The intake of sodium, chloride, and potassium is considered important to healthy nutrition and cardiovascular disease risk. Estimating the intake of these electrolytes is difficult and usually predicated on urine collections, commonly for 24 h, which are considered the gold standard. We reported on data earlier for sodium but not for potassium or chloride. We were able to test the value of 24-h urine collections in a unique, ultra-long-term balance study conducted during a simulated trip to Mars. Four healthy men were observed while ingesting 12 g salt/d, 9 g salt/d, and 6 g salt/d, while their potassium intake was maintained at 4 g/d for 105 d. Six healthy men were studied while ingesting 12 g salt/d, 9 g salt/d, and 6 g salt/d, with a re-exposure of 12 g/d, while their potassium intake was maintained at 4 g/d for 205 d. Food intake and other constituents were recorded every day for each subject. All urine output was collected daily. Long-term urine recovery rates for all 3 electrolytes were very high. Rather than the expected constant daily excretion related to daily intake, we observed remarkable daily variation in excretion, with a 7-d infradian rhythm at a relatively constant intake. We monitored 24-h aldosterone excretion in these studies and found that aldosterone appeared to be the regulator for all 3 electrolytes. We report Bland-Altman analyses on the value of urine collections to estimate intake. A single 24-h urine collection cannot predict sodium, potassium, or chloride intake; thus, multiple collections are necessary. This information is important when assessing electrolyte intake in individuals. © 2016 American Society for Nutrition.
Potassium Intake, Bioavailability, Hypertension, and Glucose Control

Directory of Open Access Journals (Sweden)

Michael S. Stone

2016-07-01

Full Text Available Potassium is an essential nutrient. It is the most abundant cation in intracellular fluid where it plays a key role in maintaining cell function. The gradient of potassium across the cell membrane determines cellular membrane potential, which is maintained in large part by the ubiquitous ion channel the sodium-potassium (Na+-K+ ATPase pump. Approximately 90% of potassium consumed (60–100 mEq is lost in the urine, with the other 10% excreted in the stool, and a very small amount lost in sweat. Little is known about the bioavailability of potassium, especially from dietary sources. Less is understood on how bioavailability may affect health outcomes. Hypertension (HTN is the leading cause of cardiovascular disease (CVD and a major financial burden ($50.6 billion to the US public health system, and has a significant impact on all-cause morbidity and mortality worldwide. The relationship between increased potassium supplementation and a decrease in HTN is relatively well understood, but the effect of increased potassium intake from dietary sources on blood pressure overall is less clear. In addition, treatment options for hypertensive individuals (e.g., thiazide diuretics may further compound chronic disease risk via impairments in potassium utilization and glucose control. Understanding potassium bioavailability from various sources may help to reveal how specific compounds and tissues influence potassium movement, and further the understanding of its role in health.
The determination of total cyanide in solutions containing uranium and gold

International Nuclear Information System (INIS)

Solomons, M.; Dixon, K.

1983-01-01

This report gives the results of a limited investigation of three distillation procedures and their variants for the separation of cyanide. The spectrophotometric measurement, which follows the distillation, uses either a mixture of pyridine and pyrazolone, or a mixture of pyridine and barbituric acid. It was found that the method published in the South Africa Government Gazette in 1969 gives quantitative recoveries from potassium cyanide solutions but not in the presence of gold. The ligand-displacement method did not give quantitative recoveries in the presence of gold, except when zinc was added to the distilland, and it then failed to give a quantitative recovery of cyanide from ferrocyanide. These two methods were therefore rejected as unsuitable for the determination of cyanide in solutions containing small amounts of uranium and gold. The procedure of the American Public Health Association (APHA) was found to give quantitative recoveries in the presence of gold, uranium, thiocyanate, and ferrocyanide when cuprous chloride, or cuprous chloride with magnesium chloride, are added to the distilland. The spectrophotometric measurement using a mixture of pyridine and barbituric acid is preferred. The calibration range of the method is 0,5 to 6μg of cyanide, and the limit of determination is 0,04μg/cm 3 . (The relative standard deviation of the method is 0,05.) The distillation time in the APHA method is approximately two and a half hours; with 3 distillation trains, up to 9 distillations can be made per day, plus a further 2 hours for the spectrophotometric determination. The preferred laboratory method is detailed in an appendix
Establishment of an in vivo potency assay for the recombinant hepatit is B surface antigen in monovalent and combined vaccines

Directory of Open Access Journals (Sweden)

Mabel Izquierdo-López

2014-12-01

Full Text Available In this paper the development of potency assay in animals (mice was made, with the objective of demonstrating the immunogenic power of the recombinant Hepatitis B surface antigen in monovalent and combined vaccines, produced at the Center of Genetic Engineering and Biotechnology. The potency test is a parameter in quality control and it is also a tool to demonstrate the consistency of the production process. Parameters such as duration of the test, number of animals in the test, as well as different areas for the maintenance of the animals were evaluated. The results on the applicability of the potency test, to two presentations of the vaccines; monovalent Heberbiovac HB and pentavalent liquid in one vial Heberpenta-L are shown, for which specificity studies, evaluating different vaccine lots, the behavior of linearity, and parallelism, as well as establishing quality specification of the test were performed. This assay led to the obtainment of reliable results for the vaccines evaluated, the consistent evaluation of the immunogenic power and the monitoring of different production processes.
21 CFR 582.1631 - Potassium hydroxide.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Potassium hydroxide. 582.1631 Section 582.1631 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Additives § 582.1631 Potassium hydroxide. (a) Product. Potassium hydroxide. (b) Conditions of use. This...
Benzannulated tris(2-mercapto-1-imidazolyl)hydroborato ligands: tetradentate κ4-S3H binding and access to monomeric monovalent thallium in an [S3] coordination environment.

Science.gov (United States)

Rong, Yi; Palmer, Joshua H; Parkin, Gerard

2014-01-21

The benzannulated tris(mercaptoimidazolyl)borohydride sodium complex, [Tm(Bu(t)Benz)]Na, has been synthesized via the reaction of NaBH4 with 1-tert-butyl-1,3-dihydro-2H-benzimidazole-2-thione, while [Tm(MeBenz)]K has been synthesized via the reaction of KBH4 with 1-methyl-1,3-dihydro-2H-benzimidazole-2-thione. The molecular structures of the solvated adducts, {[Tm(Bu(t)Benz)]Na(THF)}2(μ-THF)2 and [Tm(MeBenz)]K(OCMe2)3, have been determined by X-ray diffraction, which demonstrates that the [Tm(R)] ligands in these complexes adopt different coordination modes to that in {[Tm(MeBenz)]Na}2(μ-THF)3. Specifically, while the [Tm(MeBenz)] ligand of the sodium complex {[Tm(MeBenz)]Na}2(μ-THF)3 adopts a κ(3)-S3 coordination mode, the potassium complex [Tm(MeBenz)]K(OCMe2)3 adopts a most uncommon inverted κ(4)-S3H coordination mode in which the potassium binds to all three sulfur donors and the hydrogen of the B-H group in a linear KH-B manner. Furthermore, the [Tm(Bu(t)Benz)] ligand of {[Tm(Bu(t)Benz)]Na(THF)}2(μ-THF)2 adopts a κ(3)-S2H coordination mode, thereby demonstrating the flexibility of this ligand system. The monovalent thallium compounds, [Tm(MeBenz)]Tl and [Tm(Bu(t)Benz)]Tl, have been obtained via the corresponding reactions of [Tm(MeBenz)]Na and [Tm(Bu(t)Benz)]Na with TlOAc. X-ray diffraction demonstrates that the three sulfur donors of the [Tm(RBenz)] ligands of both [Tm(MeBenz)]Tl and [Tm(Bu(t)Benz)]Tl chelate to thallium. This coordination mode is in marked contrast to that in other [Tm(R)]Tl compounds, which exist as dinuclear molecules wherein two of the sulfur donors coordinate to different thallium centers. As such, this observation provides further evidence that benzannulation promotes κ(3)-S3 coordination in this system.
21 CFR 582.5622 - Potassium chloride.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Potassium chloride. 582.5622 Section 582.5622 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL... Supplements 1 § 582.5622 Potassium chloride. (a) Product. Potassium chloride. (b) Conditions of use. This...
International collaboration to assess the risk of Guillain Barre Syndrome following Influenza A (H1N1) 2009 monovalent vaccines

NARCIS (Netherlands)

Dodd, Caitlin N.; Romio, Silvana A.; Black, Steven; Vellozzi, Claudia; Andrews, Nick; Sturkenboom, Miriam; Zuber, Patrick; Hua, Wei; Bonhoeffer, Jan; Buttery, Jim; Crawford, Nigel; Deceuninck, Genevieve; de Vries, Corinne; De Wals, Philippe; Gutierrez-Gimeno, M. Victoria; Heijbel, Harald; Hughes, Hayley; Hur, Kwan; Hviid, Anders; Kelman, Jeffrey; Kilpi, Tehri; Chuang, S. K.; Macartney, Kristine; Rett, Melisa; Lopez-Callada, Vesta Richardson; Salmon, Daniel; Sanchez, Francisco Gimenez; Sanz, Nuria; Silverman, Barbara; Storsaeter, Jann; Thirugnanam, Umapathi; van der Maas, Nicoline; Yih, Katherine; Zhang, Tao; Izurieta, Hector

2013-01-01

Background: The global spread of the 2009 novel pandemic influenza A (H1N1) virus led to the accelerated production and distribution of monovalent 2009 Influenza A (H1N1) vaccines (pH1N1). This pandemic provided the opportunity to evaluate the risk of Guillain-Barre syndrome (GBS), which has been an
Potassium distribution in sugar cane

International Nuclear Information System (INIS)

Medina, N.H.

2014-01-01

In this work the distribution of potassium in sugarcane has been studied during its growth in two different conditions. In the first one the sugarcane soil was prepared with natural fertilizers, using sugarcane bagasse and, in another plantation the soil was prepared with commercial fertilizer NPK with a proportion of 10-10-10. For the measurement of potassium concentration in each part of the plant, gamma ray spectrometry techniques have been used to measure gamma-rays emitted from the radioisotope 40 K present in the sugarcane samples. The concentration of potassium in roots, stems and leaves were measured periodically. The results for sugarcane cultivated in soil with natural fertilizer show a higher concentration of potassium at the beginning of plant development and over time there is an oscillatory behavior in this concentration in each part of the plant, reaching a lower concentration in the adult plant. The results for the plant grown in soil with NPK fertilizer, indicate that the potassium concentration is higher in the stem at the beginning of cultivation and remained practically constant over time in various parts of the plant, with higher values in the leaves and stem than at the root. On the other hand, the results obtained using fertilizer NPK shows a lower potassium concentration, since the fertilizer provoked a much higher growth rate. (author)
The role of monovalent cations in the ATPase reaction of DNA gyrase.

Science.gov (United States)

Hearnshaw, Stephen James; Chung, Terence Tsz-Hong; Stevenson, Clare Elizabeth Mary; Maxwell, Anthony; Lawson, David Mark

2015-04-01

Four new crystal structures of the ATPase domain of the GyrB subunit of Escherichia coli DNA gyrase have been determined. One of these, solved in the presence of K(+), is the highest resolution structure reported so far for this domain and, in conjunction with the three other structures, reveals new insights into the function of this domain. Evidence is provided for the existence of two monovalent cation-binding sites: site 1, which preferentially binds a K(+) ion that interacts directly with the α-phosphate of ATP, and site 2, which preferentially binds an Na(+) ion and the functional significance of which is not clear. The crystallographic data are corroborated by ATPase data, and the structures are compared with those of homologues to investigate the broader conservation of these sites.
Ultra-long–term human salt balance studies reveal interrelations between sodium, potassium, and chloride intake and excretion12

Science.gov (United States)

Birukov, Anna; Rakova, Natalia; Lerchl, Kathrin; Engberink, Rik HG Olde; Johannes, Bernd; Wabel, Peter; Moissl, Ulrich; Rauh, Manfred; Luft, Friedrich C; Titze, Jens

2016-01-01

Background: The intake of sodium, chloride, and potassium is considered important to healthy nutrition and cardiovascular disease risk. Estimating the intake of these electrolytes is difficult and usually predicated on urine collections, commonly for 24 h, which are considered the gold standard. We reported on data earlier for sodium but not for potassium or chloride. Objective: We were able to test the value of 24-h urine collections in a unique, ultra-long–term balance study conducted during a simulated trip to Mars. Design: Four healthy men were observed while ingesting 12 g salt/d, 9 g salt/d, and 6 g salt/d, while their potassium intake was maintained at 4 g/d for 105 d. Six healthy men were studied while ingesting 12 g salt/d, 9 g salt/d, and 6 g salt/d, with a re-exposure of 12 g/d, while their potassium intake was maintained at 4 g/d for 205 d. Food intake and other constituents were recorded every day for each subject. All urine output was collected daily. Results: Long-term urine recovery rates for all 3 electrolytes were very high. Rather than the expected constant daily excretion related to daily intake, we observed remarkable daily variation in excretion, with a 7-d infradian rhythm at a relatively constant intake. We monitored 24-h aldosterone excretion in these studies and found that aldosterone appeared to be the regulator for all 3 electrolytes. We report Bland–Altman analyses on the value of urine collections to estimate intake. Conclusions: A single 24-h urine collection cannot predict sodium, potassium, or chloride intake; thus, multiple collections are necessary. This information is important when assessing electrolyte intake in individuals. PMID:27225435
21 CFR 172.160 - Potassium nitrate.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium nitrate. 172.160 Section 172.160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... Preservatives § 172.160 Potassium nitrate. The food additive potassium nitrate may be safely used as a curing...
Monovalent cations transfer through isolated human amnion: a new pharmacological model

Energy Technology Data Exchange (ETDEWEB)

Bara, M.; Guiet-Bara, A.; Durlach, J.

1985-04-01

Transfer of monovalent cations through the isolated human amnion consists of different factors: paracellular, coupling, ATPase dependent cellular transfer, leak cellular transfer. Understanding this transfer permits testing of the action of various substances. Physiological substances (Mg, taurine) increase ionic transfer and there is a vicarious effect between Mg and taurine. The tocolytic agents MgSO/sub 4/ and ethanol do not exhibit a good effect on the transfer: decrease with ethanol; equality between entry and exit fluxes with MgSO/sub 4/. On the other hand, amphotericin B increases mother-to-fetus transfer. Polluting metals (Pb, Cd, Hg, As) dramatically reduce exchanges and almost completely inhibit amnion permeability. Ingestion of ethanol also exhibits a dramatic effect on the exchange between mother and fetus through the amnion. Study of ionic transfer in vitro can be considered a pharmacological model to investigate the modifications of mother-fetus exchanges by various substances.
Diphtheria toxin-induced channels in Vero cells selective for monovalent cations

International Nuclear Information System (INIS)

Sandvig, K.; Olsnes, S.

1988-01-01

Ion fluxes associated with translocation of diphtheria toxin across the surface membrane of Vero cells were studied. When cells with surface-bound toxin were exposed to low pH to induce toxin entry, the cells became permeable to Na+, K+, H+, choline+, and glucosamine+. There was no increased permeability to Cl-, SO4(-2), glucose, or sucrose, whereas the uptake of 45 Ca2+ was slightly increased. The influx of Ca2+, which appears to be different from that of monovalent cations, was reduced by several inhibitors of anion transport and by verapamil, Mn2+, Co2+, and Ca2+, but not by Mg2+. The toxin-induced fluxes of N+, K+, and protons were inhibited by Cd2+. Cd2+ also protected the cells against intoxication by diphtheria toxin, suggesting that the open cation-selective channel is required for toxin translocation. The involvement of the toxin receptor is discussed
Proapoptotic Role of Potassium Ions in Liver Cells

Directory of Open Access Journals (Sweden)

Zhenglin Xia

2016-01-01

Full Text Available Potassium channels are transmembrane proteins that selectively promote the infiltration of potassium ions. The significance of these channels for tumor biology has become obvious. However, the effects of potassium ions on the tumor or normal cells have seldom been studied. To address this problem, we studied the biological effects of L02 and HepG2 cells with ectogenous potassium ions. Cell proliferation, cell cycle, and apoptosis rate were analyzed. Our results indicated that potassium ions inhibited proliferation of L02 and HepG2 cells and promoted their apoptosis. Potassium ions induced apoptosis through regulating Bcl-2 family members and depolarized the mitochondrial membrane, especially for HepG2 cell. These biological effects were associated with channel protein HERG. By facilitating expression of channel protein HERG, potassium ions may prevent it from being shunted to procancerous pathways by inducing apoptosis. These results demonstrated that potassium ions may be a key regulator of liver cell function. Thus, our findings suggest that potassium ions could inhibit tumorigenesis through inducing apoptosis of hepatoma cells by upregulating potassium ions transport channel proteins HERG and VDAC1.
High-Performance Thin-Film-Nanocomposite Cation Exchange Membranes Containing Hydrophobic Zeolitic Imidazolate Framework for Monovalent Selectivity

Directory of Open Access Journals (Sweden)

Jian Li

2018-05-01

Full Text Available Zeolitic imidazolate framework-8 (ZIF-8 offers good hydrothermal, chemical, and thermal stabilities, and is therefore of interest in membrane synthesis. In this work, an interfacial polymerization (IP method was applied by anchoring ZIF-8 to the skin layer of thin-ﬁlm nanocomposite (TFN membranes in order to obtain monovalent selectivity in electrodialysis. Organic trimesoyl chloride (TMC, 0.1 wt % solutions and aqueous m-phenyl diamine (MPD, 2% w/v solutions were used during the interfacial polymerization process. A range of polyamine (PA/ZIF-8 based membranes was fabricated by varying the concentration of ZIF-8 in the organic solution. The properties of the primary and modified membrane were characterized by scanning electron microscope (SEM, energy dispersive X-ray analysis (EDAX, atomic force microscopy (AFM, water uptake, ion exchange capacity, and contact angle measurements. No significant changes of the surface structure of the PA/ZIF-8 based membranes were observed. Nevertheless, the presence of ZIF-8 under the PA layer plays a key role in the separation process. For single salt solutions that were applied in electrodialysis (ED, faster transport of Na+ and Mg2+ was obtained after introducing the ZIF-8 nanoparticles, however, the desalination efficiency remained constant. When the hybrid membranes were applied to electrodialysis for binary mixtures containing Na+ as well as Mg2+, it was demonstrated that the monovalent selectivity and Na+ flux were enhanced by a higher ZIF-8 loading.
VKCDB: Voltage-gated potassium channel database

Directory of Open Access Journals (Sweden)

Gallin Warren J

2004-01-01

Full Text Available Abstract Background The family of voltage-gated potassium channels comprises a functionally diverse group of membrane proteins. They help maintain and regulate the potassium ion-based component of the membrane potential and are thus central to many critical physiological processes. VKCDB (Voltage-gated potassium [K] Channel DataBase is a database of structural and functional data on these channels. It is designed as a resource for research on the molecular basis of voltage-gated potassium channel function. Description Voltage-gated potassium channel sequences were identified by using BLASTP to search GENBANK and SWISSPROT. Annotations for all voltage-gated potassium channels were selectively parsed and integrated into VKCDB. Electrophysiological and pharmacological data for the channels were collected from published journal articles. Transmembrane domain predictions by TMHMM and PHD are included for each VKCDB entry. Multiple sequence alignments of conserved domains of channels of the four Kv families and the KCNQ family are also included. Currently VKCDB contains 346 channel entries. It can be browsed and searched using a set of functionally relevant categories. Protein sequences can also be searched using a local BLAST engine. Conclusions VKCDB is a resource for comparative studies of voltage-gated potassium channels. The methods used to construct VKCDB are general; they can be used to create specialized databases for other protein families. VKCDB is accessible at http://vkcdb.biology.ualberta.ca.

Role of monovalent alkali ions in the Yb{sup 3+} centers of CaF{sub 2} laser crystals

Energy Technology Data Exchange (ETDEWEB)

Hraiech, Sana [Physical Chemistry of Luminescent Materials (LPCML), University of Lyon, Claude Bernard/Lyon 1 University, UMR 5620 CNRS, La Doua, 69622 Villeurbanne (France); Jouini, Anis [Physical Chemistry of Luminescent Materials (LPCML), University of Lyon, Claude Bernard/Lyon 1 University, UMR 5620 CNRS, La Doua, 69622 Villeurbanne (France); IMRAM, Tohoku University, 2-1-1, Katahira, Sendai 980-8577 (Japan); Jin Kim, Kyoung [IMRAM, Tohoku University, 2-1-1, Katahira, Sendai 980-8577 (Japan); Guyot, Yannick [Physical Chemistry of Luminescent Materials (LPCML), University of Lyon, Claude Bernard/Lyon 1 University, UMR 5620 CNRS, La Doua, 69622 Villeurbanne (France); Yoshikawa, Akira [IMRAM, Tohoku University, 2-1-1, Katahira, Sendai 980-8577 (Japan); Boulon, Georges, E-mail: georges.boulon@pcml.univ-lyon1.f [Physical Chemistry of Luminescent Materials (LPCML), University of Lyon, Claude Bernard/Lyon 1 University, UMR 5620 CNRS, La Doua, 69622 Villeurbanne (France)

2010-03-15

Yb{sup 3+} and M{sup +} monovalent alkali ions (M{sup +} = Li{sup +}, Na{sup +}, K{sup +})-co-doped CaF{sub 2} cubic laser crystals were grown by the micro-pulling-down method ({mu}-PD) under CF{sub 4} atmosphere. Structural and spectroscopic characterizations of Yb{sup 3+} in substitution of Ca{sup 2+} (absorption, emission and decay curves) were carried out to study the effect of M{sup +} ions as charge compensators.
Benzannulated Tris(2-mercapto-1-imidazolyl)hydroborato Ligands: Tetradentate κ4–S3H Binding and Access to Monomeric Monovalent Thallium in an [S3] Coordination Environment

Science.gov (United States)

Rong, Yi; Palmer, Joshua H.; Parkin, Gerard

2013-01-01

The benzannulated tris(mercaptoimidazolyl)borohydride sodium complex, [TmButBenz]Na, has been synthesized via the reaction of NaBH4 with 1-tert-butyl-1,3-dihydro-2H-benzimidazole-2-thione, while [TmMeBenz]K has been synthesized via the reaction of KBH4 with 1-methyl-1,3-dihydro-2H-benzimidazole-2-thione. The molecular structures of the solvated adducts, {[TmButBenz]Na(THF)}2(μ-THF)2 and [TmMeBenz]K(OCMe2)3, have been determined by X-ray diffraction, which demonstrates that the [TmR] ligands in these complexes adopt different coordination modes to that in {[TmMeBenz]Na}2(μ-THF)3. Specifically, while the [TmMeBenz] ligand of the sodium complex {[TmMeBenz]Na}2(μ-THF)3 adopts a κ3-S3 coordination mode, the potassium complex [TmMeBenz]K(OCMe2)3 adopts a most uncommon inverted κ4-S3H coordination mode in which the potassium binds to all three sulfur donors and the hydrogen of the B–H group in a linear K•••H–B manner. Furthermore, the [TmButBenz] ligand of {[TmButBenz]Na(THF)}2(μ-THF)2 adopts a κ3-S2H coordination mode, thereby demonstrating the flexibility of this ligand system. The monovalent thallium compounds, [TmMeBenz]Tl and [TmButBenz]Tl, have been obtained via the corresponding reactions of [TmMeBenz]Na and [TmButBenz]Na with TlOAc. X-ray diffraction demonstrates that the three sulfur donors of the [TmRBenz] ligands of both [TmMeBenz]Tl and [TmButBenz]Tl chelate to thallium. This coordination mode is in marked contrast to that in other [TmR]Tl compounds, which exist as dinuclear molecules wherein two of the sulfur donors coordinate to different thallium centers. As such, this observation provides further evidence that benzannulation promotes κ3-S3 coordination in this system. PMID:24201311
Impedance and dielectric characterizations of ionic partitioning in interfaces that membranous, biomimetic and gold surfaces form with electrolytes

International Nuclear Information System (INIS)

Chilcott, Terry C.; Guo, Chuan

2013-01-01

Silicon dioxide, organic monolayers covalently attached to silicon and gold are used as biosensor substrates and anchoring platforms for hybrid, tethered and supported lipid membranes used in membrane-protein studies. Electrical impedance spectroscopy (EIS) studies of gold in contact with potassium chloride electrolytes of concentrations ranging from 1 mM to 300 mM, characterized the gold–electrolyte interface as principally a Stern layer 20–30 Å thick and conductivity many orders of magnitude less than that of the bulk electrolyte. EIS studies of SiO 2 –electrolyte system that were similar to studies of a tetradecane–electrolyte system are presented herein that reveal an interface comprised of at least two interfacial layers and extending some 10 5 Å into the electrolyte. The average conductivity and thickness values for the layer in contact with the SiO 2 surface (∼10 −6 S m −1 and ∼28 Å, respectively) were of the order of magnitude expected for the Gouy–Chapman layer but the dependency of the thickness on concentration did not reflect the expected dependency of the Debye length over the full range of concentrations. The average values for the next layer (∼10 −3 S m −1 and ∼10 5 Å) exhibited a dependency on concentration similar to that expected for the bulk electrolyte. The theoretical derivations of ionic partitioning arising from the Born (dielectric) energy distributions in both the SiO 2 and gold interfaces were generally consistent with the respective EIS studies and revealed that partitioning in the SiO 2 interface mimicked that in bio-membranous interfaces. The dielectric characterizations suggest that; ionic partitioning in biomimetic interfaces play a role in long-ranging sequestration of organic molecules, the extensiveness of these interfaces contributes to differences in the lipid densities of bilayers formed on biomimetic substrates, and chloride ions have a greater affinity than the smaller potassium ions for gold
International collaboration to assess the risk of Guillain Barré Syndrome following Influenza A (H1N1) 2009 monovalent vaccines

NARCIS (Netherlands)

C. Dodd (Caitlin); S.A. Romio (Silvana); S. Black (Steve); C. Vellozzi (Claudia); N.J. Andrews (Nick); M.C.J.M. Sturkenboom (Miriam); P. Zuber (Patrick); W. Hua (Wei); J. Bonhoeffer (Jan); J. Buttery (Jim); N. Crawford (Nigel); G. Deceuninck (Genevieve); C.S. de Vries (Corinne); P. de Wals (Philippe); D. Gimeno (David); H. Heijbel (Harald); H. Hughes (Hayley); K. Hur (Kwan); A. Hviid (Anders); J. Kelman (Jeffrey); T. Kilpi (Tehri); S.K. Chuang (S.); T. Macartney (Thomas); M. Rett (Melisa); V.R. Lopez-Callada (Vesta Richardson); D. Salmon (Daniel); F.G. Sanchez (Francisco Gimenez); N. Sanz (Nuria); B. Silverman (Bernard); J. Storsaeter (Jann); U. Thirugnanam (Umapathi); N.A.T. van der Maas (Nicoline); K. Yih (Katherine); T. Zhang (Teng Fei); H.S. Izurieta (Hector); B.J. Addis; A. Akhtar (Aysha); J. Cope (Judith); R.L. Davis (Robert); P. Gargiullo (Paul); X. Kurz (Xavier); B. Law (Barbara); I. Sahinovic (Isabelle); J. Tokars (Jerry); P. Serrano (Pedro); A. Cheng (Aixin); N.J. Andrews (Nick); P. Charles (Pat); H. Clothier (Hazel); B. Day (Bruce); T. Day (Timothy); P. Gates (Peter); R. MacDonnell (Richard); L. Roberts (Les); V. Rodriguez-Casero (Vic-toria); T. Wijeratne (Tissa); H.A.L. Kiers (Henk); C. Blyth (Christopher); R. Booy (Robert); E. Elliott (Elizabeth); M.R. Gold (Michael); H. Marshall; P. McIntyre (Peter); P. Richmond (Peter); J. Royle (Jenny); N.W. Wood (Nicholas); Y. Zurynski (Yvonne); G. Calvo (Gonzalo); M. Campins (Magda); N. Corominas (Nuria); F. Torres (Ferran); V. Valls; A. Vilella (Ángels); A. Dutra (Amalia); A. Eick-Cost (Angelia); H.M. Jackson (Henry); K. Garman (Katherine); Z. Hu (Zheng); J. Rigo; J. Badoo (Judith); D Cho (David); L.L. Polakowski (Laura); S.K. Sandhu (Sukhminder); G. Sun (Guoying); H.-S.S. Chan (Hoi-Shan Sophelia); K.-Y. Chan (Kwok-Yin); R. Cheung (Raymond); Y-F. Cheung (Yuk-Fai); S. Cherk (Sharon); S.K Chuang (S.); D. Fok (Dennis); B.-H. Fung (Bun-Hey); K.-F. Ko (Kwai-Fu); K.W. Lau (Ka Wing); K.-K. Lau (Kwok-Kwong); P. Li (Pulin); H.-T. Liu (Hui-Tung); S.-H. Liu (Shao-Haei); K. Mok (Kin); J. So (Joanna); W. Wong (Winnie); S.-P. Wu (Shun-Ping); V. Avagyan (Vardan); R. Ball (Robert); D. Burwen (Dale); R.L. Franks (Riley); J.M. Gibbs (Jonathan); R.E. Kliman (Rebecca); S. Kropp (Silke); T.E. MaCurdy (Thomas); D.B. Martin (David); S.-D.K. Sandhu (Sukhmin-Der); B.B. Worrall (Bradford B.); D.E.F. Fuentes (Dra. Elvira Fuentes); P.C.O. González (Paola Carolina Ojeda); V.F. Reyna (Valerie ); M. Kulldorff (Martin); G. Lee (Grace); T.A. Lieu (Tracy); S. Platt; G.D. Serres (Gaston De); K. Jabin (Kamilah); B.L.S. Soh (Bee Leng Sally); L. Arnheim-Dahlström (Lisen); A. Castot (Anne); H.E. de Melker (Hester); J.P. Dieleman (Jeanne); J. Hallgren (Jonal); B.C. Jacobs (Bart); K. Johansen (Kari); P Kramarz (Piotr); M. Lapeyre (Maryse); T. Leino (Tuija); D. Mølgaard-Nielsen (Ditte); M. Mosseveld (Mees); H.K. Olberg (Henning K); C.-M. Sammon (Cor-Mac); C. Saussier (Christel); M.J. Schuemie (Martijn); A. Sommet (Agnès); P. Sparen (Pär); H. Svanström (Henrik); A.M. Vanrolleghem (Ann M.); D.M. Weibel (Daniel); J.D. Domingo (Javier Diez); J.L. Esparza (José LuísMicó); R.M.O. Lucas (Rafael M. Ortí); J.B.M. Maseres (Juan B. Mollar); J.L.A. Sánchez (José Luís Alfonso); M.G. Sánchez (Mercedes Garcés); V.Z. Viguer (Vicente Zanón); F. Cunningham (Francesca); B. Thakkar (Bharat); R. Zhang (Rongping)

2013-01-01

textabstractBackground: The global spread of the 2009 novel pandemic influenza A (H1N1) virus led to the accelerated production and distribution of monovalent 2009 Influenza A (H1N1) vaccines (pH1N1). This pandemic provided the opportunity to evaluate the risk of Guillain-Barré syndrome (GBS), which
Potassium-doped n-type bilayer graphene

Science.gov (United States)

Yamada, Takatoshi; Okigawa, Yuki; Hasegawa, Masataka

2018-01-01

Potassium-doped n-type bilayer graphene was obtained. Chemical vapor deposited bilayer and single layer graphene on copper (Cu) foils were used. After etching of Cu foils, graphene was dipped in potassium hydroxide aqueous solutions to dope potassium. Graphene on silicon oxide was characterized by X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDX), and Raman spectroscopy. Both XPS and EDX spectra indicated potassium incorporation into the bilayer graphene via intercalation between the graphene sheets. The downward shift of the 2D peak position of bilayer graphene after the potassium hydroxide (KOH) treatment was confirmed in Raman spectra, indicating that the KOH-treated bilayer graphene was doped with electrons. Electrical properties were measured using Hall bar structures. The Dirac points of bilayer graphene were shifted from positive to negative by the KOH treatment, indicating that the KOH-treated bilayer graphene was n-type conduction. For single layer graphene after the KOH treatment, although electron doping was confirmed from Raman spectra, the peak of potassium in the X-ray photoelectron spectroscopy (XPS) spectrum was not detected. The Dirac points of single layer graphene with and without the KOH treatment showed positive.
Potassium chloride production by microcline chlorination

Energy Technology Data Exchange (ETDEWEB)

Orosco, Pablo, E-mail: porosco@unsl.edu.ar [Instituto de Investigaciones en Tecnología Química (INTEQUI), Chacabuco y Pedernera, San Luis (Argentina); Facultad de Química, Bioquímica y Farmacia, Universidad Nacional de San Luis, Chacabuco y Pedernera, San Luis (Argentina); Ruiz, María del Carmen [Instituto de Investigaciones en Tecnología Química (INTEQUI), Chacabuco y Pedernera, San Luis (Argentina)

2015-08-10

Highlights: • Use of chlorination for the KCl production. • The reagents used were microcline, hydromagnesite and chlorine. • Isothermal and non-isothermal assays were performed in Cl{sub 2}–N{sub 2} mixture. • The chlorination generated KCl at 700 °C. • The chlorination products promote KCl formation. - Abstract: The potassium chloride is one of the most important fertilizers used in agriculture. The current demand of this salt makes interesting the study of potassium chloride production from unconventional potassium resources. In this work the potassium chloride production by chlorination of microcline was investigated. The starting reagents were microcline, hydromagnesite and chlorine. Non-isothermal and isothermal chlorination assays were carried out in a thermogravimetric device adapted to work in corrosive atmospheres. The temperature effect on potassium extraction and the phase transformations produced during chlorination of microcline were studied. The reagents and reaction products were analyzed by X-ray fluorescence (XRF) and X-ray diffraction (XRD). The experimental results indicated that by chlorination of microcline an important extraction of potassium in the temperature range from 800 to 900 °C was produced. Moreover, at 800 °C the forsterite, enstatite and magnesium aluminate spinel phases were generated.
Design and fabrication of a 3D-structured gold film with nanopores for local electric field enhancement in the pore

International Nuclear Information System (INIS)

Grant-Jacob, James A; Zin Oo, Swe; Carpignano, Francesca; Brocklesby, William S; Melvin, Tracy; Boden, Stuart A; Charlton, Martin D B

2016-01-01

Three-dimensionally structured gold membrane films with nanopores of defined, periodic geometries are designed and fabricated to provide the spatially localised enhancement of electric fields by manipulation of the plasmons inside nanopores. Square nanopores of different size and orientation relative to the pyramid are considered for films in aqueous and air environments, which allow for control of the position of electric fields within the structure. Designs suitable for use with 780 nm light were created. Here, periodic pyramidal cavities produced by potassium hydroxide etching to the {111} planes of (100) silicon substrates are used as templates for creating a periodic, pyramidal structured, free-standing thin gold film. Consistent with the findings from the theoretical studies, a nano-sized hole of 50 nm square was milled through the gold film at a specific location in the cavity to provide electric field control which can subsequently used for enhancement of fluorescence or Raman scattering of molecules in the nanopore. (paper)
Design and fabrication of a 3D-structured gold film with nanopores for local electric field enhancement in the pore

Science.gov (United States)

Grant-Jacob, James A.; Zin Oo, Swe; Carpignano, Francesca; Boden, Stuart A.; Brocklesby, William S.; Charlton, Martin D. B.; Melvin, Tracy

2016-02-01

Three-dimensionally structured gold membrane films with nanopores of defined, periodic geometries are designed and fabricated to provide the spatially localised enhancement of electric fields by manipulation of the plasmons inside nanopores. Square nanopores of different size and orientation relative to the pyramid are considered for films in aqueous and air environments, which allow for control of the position of electric fields within the structure. Designs suitable for use with 780 nm light were created. Here, periodic pyramidal cavities produced by potassium hydroxide etching to the {111} planes of (100) silicon substrates are used as templates for creating a periodic, pyramidal structured, free-standing thin gold film. Consistent with the findings from the theoretical studies, a nano-sized hole of 50 nm square was milled through the gold film at a specific location in the cavity to provide electric field control which can subsequently used for enhancement of fluorescence or Raman scattering of molecules in the nanopore.
Gold monetization and gold discipline

OpenAIRE

Robert P. Flood; Peter M. Garber

1981-01-01

The paper is a study of the price level and relative price effects of a policy to monetize gold and fix its price at a given future time and at the then prevailing nominal price. Price movements are analyzed both during the transition to the gold standard and during the post-monetization period. The paper also explores the adjustments to fiat money which are necessary to ensure that this type of gold monetization is non-inflationary. Finally, some conditions which produce a run on the governm...
Race, Serum Potassium, and Associations With ESRD and Mortality.

Science.gov (United States)

Chen, Yan; Sang, Yingying; Ballew, Shoshana H; Tin, Adrienne; Chang, Alex R; Matsushita, Kunihiro; Coresh, Josef; Kalantar-Zadeh, Kamyar; Molnar, Miklos Z; Grams, Morgan E

2017-08-01

Recent studies suggest that potassium levels may differ by race. The basis for these differences and whether associations between potassium levels and adverse outcomes differ by race are unknown. Observational study. Associations between race and potassium level and the interaction of race and potassium level with outcomes were investigated in the Racial and Cardiovascular Risk Anomalies in Chronic Kidney Disease (RCAV) Study, a cohort of US veterans (N=2,662,462). Associations between African ancestry and potassium level were investigated in African Americans in the Atherosclerosis Risk in Communities (ARIC) Study (N=3,450). Race (African American vs non-African American and percent African ancestry) for cross-sectional analysis; serum potassium level for longitudinal analysis. Potassium level for cross-sectional analysis; mortality and end-stage renal disease for longitudinal analysis. The RCAV cohort was 18% African American (N=470,985). Potassium levels on average were 0.162mmol/L lower in African Americans compared with non-African Americans, with differences persisting after adjustment for demographics, comorbid conditions, and potassium-altering medication use. In the ARIC Study, higher African ancestry was related to lower potassium levels (-0.027mmol/L per each 10% African ancestry). In both race groups, higher and lower potassium levels were associated with mortality. Compared to potassium level of 4.2mmol/L, mortality risk associated with lower potassium levels was lower in African Americans versus non-African Americans, whereas mortality risk associated with higher levels was slightly greater. Risk relationships between potassium and end-stage renal disease were weaker, with no difference by race. No data for potassium intake. African Americans had slightly lower serum potassium levels than non-African Americans. Consistent associations between potassium levels and percent African ancestry may suggest a genetic component to these differences. Higher and
Plasmonic gold nanoparticles for detection of fungi and human cutaneous fungal infections.

Science.gov (United States)

Sojinrin, Tobiloba; Conde, João; Liu, Kangze; Curtin, James; Byrne, Hugh J; Cui, Daxiang; Tian, Furong

2017-07-01

Fungi, which are common in the environment, can cause a multitude of diseases. Warm, humid conditions allow fungi to grow and infect humans via the respiratory, digestive and reproductive tracts, genital area and other bodily interfaces. Fungi can be detected directly by microscopy, using the potassium hydroxide test, which is the gold standard and most popular method for fungal screening. However, this test requires trained personnel operating specialist equipment, including a fluorescent microscope and culture facilities. As most acutely infected patients seek medical attention within the first few days of symptoms, the optimal diagnostic test would be rapid and self-diagnostic simplifying and improving the therapeutic outcome. In suspensions of gold nanoparticles, Aspergillus niger can cause a colour change from red to blue within 2 min, as a result of changes in nanoparticle shape. A similar colour change was observed in the supernatant of samples of human toenails dispersed in water. Scanning electron microscopy, UV/Vis and Raman spectroscopy were employed to monitor the changes in morphology and surface plasmon resonance of the nanoparticles. The correlation of colour change with the fungal infection was analysed using the absorbance ratio at 520 nm/620 nm. We found a decrease in the ratio when the fungi concentration increased from 1 to 16 CFU/mL, with a detection limit of 10 CFU/mL. The test had an 80% sensitivity and a 95% specificity value for the diagnosis of athlete's foot in human patients. This plasmonic gold nanoparticle-based system for detection of fungal infections measures the change in shape of gold nanoparticles and generates coloured solutions with distinct tonality. Our application has the potential to contribute to self-diagnosis and hygiene control in laboratories/hospitals with fewer resources, just using the naked eye. Graphical abstract Colorimetric method for fungi detection with gold nano particles.
Leaching of potassium in a lysimeter experiment

International Nuclear Information System (INIS)

Gerzabek, M.H.

1996-11-01

Leaching of potassium was studied in the lysimeter plant in Seibersdorf/Austria (Pannonian climate). Averaged over three years, gravitational water amounted to 15.7% of the sum of precipitation (mean 485 mm) and irrigation (mean 138 mm). Differences between the four soils with respect to drainage were explained by the specific percentage of the soil skeleton. The average yearly potassium leaching ranged from 3.64 kg K/ha·yr (Dystric-Cambisol) to 22.7 kg K/ha·yr (drained Gleysol). Correlation between gravitational water volume and potassium leaching were only significant for one out of four soil types. No correlation was observed between extractable potassium in the soil profiles and potassium leaching. (author)
Solvation of monovalent anions in formamide and methanol: Parameterization of the IEF-PCM model

International Nuclear Information System (INIS)

Boees, Elvis S.; Bernardi, Edson; Stassen, Hubert; Goncalves, Paulo F.B.

2008-01-01

The thermodynamics of solvation for a series of monovalent anions in formamide and methanol has been studied using the polarizable continuum model (PCM). The parameterization of this continuum model was guided by molecular dynamics simulations. The parameterized PCM model predicts the Gibbs free energies of solvation for 13 anions in formamide and 16 anions in methanol in very good agreement with experimental data. Two sets of atomic radii were tested in the definition of the solute cavities in the PCM and their performances are evaluated and discussed. Mean absolute deviations of the calculated free energies of solvation from the experimental values are in the range of 1.3-2.1 kcal/mol
Dietary reference values for potassium

DEFF Research Database (Denmark)

Sjödin, Anders Mikael

2016-01-01

Following a request from the European Commission, the EFSA Panel on Dietetic Products, Nutrition and Allergies (NDA) derives dietary reference values (DRVs) for potassium. The Panel decides to set DRVs on the basis of the relationships between potassium intake and blood pressure and stroke...
Ammonium nitrate-potassium nitrate system

Energy Technology Data Exchange (ETDEWEB)

Cady, H.H.

1981-01-01

A portion of the binary phase diagram for the system ammonium nitrate-potassium nitrate has been determined from -55/sup 0/C to 185/sup 0/C. Results are presented for the ammonium-nitrate-rich end of the system up to 30 wt% potassium nitrate.
Mimicking the cell membrane: bio-inspired simultaneous functions with monovalent anion selectivity and antifouling properties of anion exchange membrane

Science.gov (United States)

Zhao, Yan; Liu, Huimin; Tang, Kaini; Jin, Yali; Pan, Jiefeng; der Bruggen, Bart Van; Shen, Jiangnan; Gao, Congjie

2016-01-01

A new bio-inspired method was applied in this study to simultaneously improve the monovalent anion selectivity and antifouling properties of anion exchange membranes (AEMs). Three-layer architecture was developed by deposition of polydopamine (PDA) and electro-deposition of N-O-sulfonic acid benzyl chitosan (NSBC). The innermost and outermost layers were PDA with different deposition time. The middle layer was prepared by NSBC. Fourier transform infrared spectroscopy and scanning electron microscopy confirmed that PDA and NSBC were successfully modified on the surfaces of AEMs. The contact angle of the membranes indicated an improved hydrophilicity of the modified membranes. A series of electrodialysis experiments in which Cl−/SO42− separation was studied, demonstrating the monovalent anion selectivity of the samples. The Cl−/SO42− permselectivity of the modified membranes can reach up to 2.20, higher than that of the commercial membrane (only 0.78) during 90 minutes in electrodialysis (ED). The increase value of the resistance of the membranes was also measured to evaluate the antifouling properties. Sodium dodecyl benzene sulfonate (SDBS) was used as the fouling material in the ED process and the membrane area resistance of modified membrane increase value of was only 0.08 Ωcm2 30 minutes later. PMID:27853255
Mimicking the cell membrane: bio-inspired simultaneous functions with monovalent anion selectivity and antifouling properties of anion exchange membrane

Science.gov (United States)

Zhao, Yan; Liu, Huimin; Tang, Kaini; Jin, Yali; Pan, Jiefeng; der Bruggen, Bart Van; Shen, Jiangnan; Gao, Congjie

2016-11-01

A new bio-inspired method was applied in this study to simultaneously improve the monovalent anion selectivity and antifouling properties of anion exchange membranes (AEMs). Three-layer architecture was developed by deposition of polydopamine (PDA) and electro-deposition of N-O-sulfonic acid benzyl chitosan (NSBC). The innermost and outermost layers were PDA with different deposition time. The middle layer was prepared by NSBC. Fourier transform infrared spectroscopy and scanning electron microscopy confirmed that PDA and NSBC were successfully modified on the surfaces of AEMs. The contact angle of the membranes indicated an improved hydrophilicity of the modified membranes. A series of electrodialysis experiments in which Cl-/SO42- separation was studied, demonstrating the monovalent anion selectivity of the samples. The Cl-/SO42- permselectivity of the modified membranes can reach up to 2.20, higher than that of the commercial membrane (only 0.78) during 90 minutes in electrodialysis (ED). The increase value of the resistance of the membranes was also measured to evaluate the antifouling properties. Sodium dodecyl benzene sulfonate (SDBS) was used as the fouling material in the ED process and the membrane area resistance of modified membrane increase value of was only 0.08 Ωcm2 30 minutes later.
Neural synchronization via potassium signaling

DEFF Research Database (Denmark)

Postnov, Dmitry E; Ryazanova, Ludmila S; Mosekilde, Erik

2006-01-01

Using a relatively simple model we examine how variations of the extracellular potassium concentration can give rise to synchronization of two nearby pacemaker cells. With the volume of the extracellular space and the rate of potassium diffusion as control parameters, the dual nature of this reso...
Coal-gold agglomeration: an alternative separation process in gold recovery

Energy Technology Data Exchange (ETDEWEB)

Akcil, A.; Wu, X.Q.; Aksay, E.K. [Suleyman Demirel University, Isparta (Turkey). Dept. of Mining Engineering

2009-07-01

Considering the increasing environmental concerns and the potential for small gold deposits to be exploited in the future, the uses of environmentally friendly processes are essential. Recent developments point to the potential for greatly increased plant performance through a separation process that combines the cyanide and flotation processes. In addition, this kind of alternative treatment processes to the traditional gold recovery processes may reduce the environmental risks of present small-scale gold mining. Gold recovery processes that applied to different types of gold bearing ore deposits show that the type of deposits plays an important role for the selection of mineral processing technologies in the production of gold and other precious metals. In the last 25 years, different alternative processes have been investigated on gold deposits located in areas where environmental issues are a great concern. In 1988, gold particles were first recovered by successful pilot trial of coal-gold agglomeration (CGA) process in Australia. The current paper reviews the importance of CGA in the production of gold ore and identifies areas for further development work.
Genetics Home Reference: potassium-aggravated myotonia

Science.gov (United States)

... aggravated by eating potassium-rich foods such as bananas and potatoes. Stiffness occurs in skeletal muscles throughout the body. Potassium-aggravated myotonia ranges in severity from mild episodes ...

Phage based green chemistry for gold ion reduction and gold retrieval.

Science.gov (United States)

Setyawati, Magdiel I; Xie, Jianping; Leong, David T

2014-01-22

The gold mining industry has taken its toll on the environment, triggering the development of more environmentally benign processes to alleviate the waste load release. Here, we demonstrate the use of bacteriophages (phages) for biosorption and bioreduction of gold ions from aqueous solution, which potentially can be applied to remediate gold ions from gold mining waste effluent. Phage has shown a remarkably efficient sorption of gold ions with a maximum gold adsorption capacity of 571 mg gold/g dry weight phage. The product of this phage mediated process is gold nanocrystals with the size of 30-630 nm. Biosorption and bioreduction processes are mediated by the ionic and covalent interaction between gold ions and the reducing groups on the phage protein coat. The strategy offers a simple, ecofriendly and feasible option to recover of gold ions to form readily recoverable products of gold nanoparticles within 24 h.
31 CFR 100.4 - Gold coin and gold certificates in general.

Science.gov (United States)

2010-07-01

... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Gold coin and gold certificates in... EXCHANGE OF PAPER CURRENCY AND COIN In General § 100.4 Gold coin and gold certificates in general. Gold coins, and gold certificates of the type issued before January 30, 1934, are exchangeable, as provided...
Gold and gold working in Late Bronze Age Northern Greece

Science.gov (United States)

Vavelidis, M.; Andreou, S.

2008-04-01

Numerous objects of gold displaying an impressive variety of types and manufacturing techniques are known from the Late Bronze Age (LBA) contexts of Mycenaean Greece, but very little is known about the origin and processing of gold during the second millennium b.c. Ancient literature and recent research indicate that northern Greece is probably the richest gold-bearing region in Greece, and yet, very little evidence exists regarding the exploitation of its deposits and the production as well as use of gold in the area during prehistory. The unusual find of a group of small stone crucibles at the prehistoric settlement of Thessaloniki Toumba, one with visible traces of gold melting, proves local production and offers a rare opportunity to examine the process of on-site gold working. Furthermore, the comparison of the chemical composition of prehistoric artefacts from two settlements with those of gold deposits in their immediate areas supports the local extraction of gold and opens up the prospect for some of the Mycenaean gold to have originated in northern Greece. The scarcity of gold items in northern Greek LBA contexts may not represent the actual amount of gold produced and consumed, but could be a result of the local social attitudes towards the circulation and deposition of artefacts from precious metals.
Usability of #betta#-spectrometric method to prospecting for copper-porphyric skarn and gold-quartz-sulfide deposits

International Nuclear Information System (INIS)

Syromyatnikov, N.G.; Ivanova, Eh.I.; Karpukhin, V.G.; Trofimova, L.A.; Tolmachev, I.I.

1982-01-01

Possibility of the prospecting for non-radioactive element deposits by means of radioactive elements as indicators is studied. Radioactive elements (uranium, thorium and potassium) were determined by gamma spectroscopy. Radiometric methods of prospecting are effective and economical. Clark contents of radioelements in rocks were determined in situ by field gamma spectrometers. It is established that copper-porphyric deposits are regularly controlled from the surface by aureoles of increased uranium contents, which sizes reach 400x500 m and can be revealed by gamma spectroscopy during 1:25000 and more large-scale survey. Skarn-ore zones of deposits of different mineral types (copper, polymetallic, iron ore ones) are fixed on the surface by increased radioactivity; this fact can be used as search criterion. Gold-bearing quartz veins differ from barren lodes by a higher level of total radioactivity and high potassium content. Top walls of ore-bearing quartz veins are mainly enriched by radioelements
Evaluation of the Characteristics of the Adsorption of Fibrinogen ...

African Journals Online (AJOL)

... with calcium and magnesium ions increased the amount of fibrinogen adsorbed onto it as against treatment with potassium ion (a monovalent ion). Electrostatic attraction on the surface of the treated HAP and hydrogen are responsible for the adsorption. The results are useful in fabricating bone and teeth implants that are ...
Gold-Mining

DEFF Research Database (Denmark)

Raaballe, J.; Grundy, B.D.

2002-01-01

Based on standard option pricing arguments and assumptions (including no convenience yield and sustainable property rights), we will not observe operating gold mines. We find that asymmetric information on the reserves in the gold mine is a necessary and sufficient condition for the existence...... of operating gold mines. Asymmetric information on the reserves in the mine implies that, at a high enough price of gold, the manager of high type finds the extraction value of the company to be higher than the current market value of the non-operating gold mine. Due to this under valuation the maxim of market...
Qualitative Carbohydrate Analysis using Alkaline Potassium ...

Indian Academy of Sciences (India)

IAS Admin

CLASSROOM. 285. RESONANCE | March 2016. Qualitative Carbohydrate Analysis using Alkaline. Potassium Ferricyanide. Keywords. Alkaline potassium ferricyanide, qualitative ... Carbohydrates form a distinct class of organic compounds often .... Laboratory Techniques: A contemporary Approach, W B Saunders Com-.
Suicidal ingestion of potassium permanganate crystals: a rare encounter.

Science.gov (United States)

Karthik, Ravikanti; Veerendranath, Hari Prasad Kanakapura; Wali, Siddraj; Mohan, Murali N T; Kumar, Praveen A C; Trimurty, Gaganam

2014-01-01

Potassium permanganate poisoning is not common. Although Symptoms of potassium permanganate ingestion are gastrointestinal and Complications due to ingestion of potassium permanganate include cardiovascular depression, hepatic and renal damage, upper airway obstruction, bleeding tendency and methemoglobinemia. Gastric damage due to potassium permanganate has rarely been reported previously. We are reporting a 34-year old female patient who presented to our Emergency Department after suicidal ingestion of potassium permanganate crystals. After treatment, the patient was discharged home on the 8(th) day after admission. So we conclude that Emergency endoscopy has a significant role in diagnosis and management of potassium permanganate ingestion.
Gold Nanoparticles Obtained by Bio-precipitation from Gold(III) Solutions

International Nuclear Information System (INIS)

Gardea-Torresdey, J.L.; Tiemann, K.J.; Gamez, G.; Dokken, K.; Tehuacanero, S.; Jose-Yacaman, M.

1999-01-01

The use of metal nanoparticles has shown to be very important in recent industrial applications. Currently gold nanoparticles are being produced by physical methods such as evaporation. Biological processes may be an alternative to physical methods for the production of gold nanoparticles. Alfalfa biomass has shown to be effective at passively binding and reducing gold from solutions containing gold(III) ions and resulting in the formation of gold(0) nanoparticles. High resolution microscopy has shown that five different types of gold particles are present after reaction with gold(III) ions with alfalfa biomass. These particles include: fcc tetrahedral, hexagonal platelet, icosahedral multiple twinned, decahedral multiple twinned, and irregular shaped particles. Further analysis on the frequency of distribution has shown that icosahedral and irregular particles are more frequently formed. In addition, the larger particles observed may be formed through the coalescence of smaller particles. Through modification of the chemical parameters, more uniform particle size distribution may be obtained by the alfalfa bio-reduction of gold(III) from solution
Size fraction assaying of gold bearing rocks (for gold extraction) by ...

African Journals Online (AJOL)

A novel method has been developed for processing and extraction of gold from gold bearing rocks for use by small-scale gold miners in Ghana. The methodology involved crushing of gold bearing hard rocks to fine particles to form a composite sample and screening at a range of sizes. Gold distribution in the composite ...
X-ray absorption in atomic potassium

International Nuclear Information System (INIS)

Gomilsek, Jana Padeznik; Kodre, Alojz; Arcon, Iztok; Nemanic, Vincenc

2008-01-01

A new high-temperature absorption cell for potassium vapor is described. X-ray absorption coefficient of atomic potassium is determined in the energy interval of 600 eV above the K edge where thresholds for simultaneous excitations of 1s and outer electrons, down to [1s2p] excitation, appear. The result represents also the atomic absorption background for XAFS (X-ray absorption fine structure) structure analysis. The K ionization energy in the potassium vapor is determined and compared with theoretical data and with the value for the metal
Potassium test

Science.gov (United States)

... hyperkalemia ) may be due to: Addison disease (rare) Blood transfusion Certain medicines Crushed tissue injury Hyperkalemic periodic paralysis ... released. This may cause a falsely high result. Alternative Names Hypokalemia test; K+ Images Blood test References Mount DB. Disorders of potassium balance. ...
Evaluation of radioiodinated and radiocopper labeled monovalent fragments of monoclonal antibody chCE7 for targeting of neuroblastoma

International Nuclear Information System (INIS)

Carrel, Francois; Amstutz, Hanspeter; Novak-Hofer, Ilse; Schubiger, P. August

1997-01-01

Monovalent fragments of antineuroblastoma antibody mAb chCE7 were evaluated for their in vitro and in vivo tumor cell binding properties. Single chain fragments were constructed from the variable region genes cloned from hybridoma cells, expressed in E.coli and purified by metal chelate affinity chromatography. Radioiodinated CE7-scFv fragments were found to bind with high affinity (K d ∼10 -9 M) to target cells in vitro but formed aggregates at 37 deg. C, and bound to serum proteins in vitro and in vivo. Circular Dichroism spectra revealed the protein to be in a conformationally altered form and no permanent 'refolding' could be achieved. In contrast, chCE7-Fab fragments were found to bind to target tumor cells with similar affinity than the parent mAb chCE7 (K d ∼10 -10 M), showed no tendency to aggregate and were stable in serum both in vitro and in vivo. Kinetics of association and dissociation of radioiodinated scFv and Fab fragments were found to be rapid. Radioiodination with the Iodogen method led to impaired immunoreactivity which was found to further increase the off- rates of radioiodinated fragments from tumor cells. Radioiodination with the Bolton-Hunter reagent as well as labeling of chCE7-Fab fragments with 67 Cu via the macrocyclic CPTA ligand led to fully immunoreactive Fab fragments. Radioiodinated and radiocopper labeled monovalent CE7 fragments did not internalize into target tumor cells as the parent mAb and its F(ab') 2 fragment. A comparison of the biodistribution in tumor bearing nude mice of the radiocopper labeled monovalent, non internalizing Fab fragments with the internalizing divalent F(ab') 2 fragments showed in both cases high levels of radioactivity in the kidneys. Concerning tumor uptake, radioactivity from both internalizing and non internalizing fragments remained associated with tumor tissue for longer times than in case of the corresponding radioiodinated fragments. When compared with the radioiodinated forms, tumor uptake
A novel antibody engineering strategy for making monovalent bispecific heterodimeric IgG antibodies by electrostatic steering mechanism.

Science.gov (United States)

Liu, Zhi; Leng, Esther C; Gunasekaran, Kannan; Pentony, Martin; Shen, Min; Howard, Monique; Stoops, Janelle; Manchulenko, Kathy; Razinkov, Vladimir; Liu, Hua; Fanslow, William; Hu, Zhonghua; Sun, Nancy; Hasegawa, Haruki; Clark, Rutilio; Foltz, Ian N; Yan, Wei

2015-03-20

Producing pure and well behaved bispecific antibodies (bsAbs) on a large scale for preclinical and clinical testing is a challenging task. Here, we describe a new strategy for making monovalent bispecific heterodimeric IgG antibodies in mammalian cells. We applied an electrostatic steering mechanism to engineer antibody light chain-heavy chain (LC-HC) interface residues in such a way that each LC strongly favors its cognate HC when two different HCs and two different LCs are co-expressed in the same cell to assemble a functional bispecific antibody. We produced heterodimeric IgGs from transiently and stably transfected mammalian cells. The engineered heterodimeric IgG molecules maintain the overall IgG structure with correct LC-HC pairings, bind to two different antigens with comparable affinity when compared with their parental antibodies, and retain the functionality of parental antibodies in biological assays. In addition, the bispecific heterodimeric IgG derived from anti-HER2 and anti-EGF receptor (EGFR) antibody was shown to induce a higher level of receptor internalization than the combination of two parental antibodies. Mouse xenograft BxPC-3, Panc-1, and Calu-3 human tumor models showed that the heterodimeric IgGs strongly inhibited tumor growth. The described approach can be used to generate tools from two pre-existent antibodies and explore the potential of bispecific antibodies. The asymmetrically engineered Fc variants for antibody-dependent cellular cytotoxicity enhancement could be embedded in monovalent bispecific heterodimeric IgG to make best-in-class therapeutic antibodies. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.
Errors in potassium balance

International Nuclear Information System (INIS)

Forbes, G.B.; Lantigua, R.; Amatruda, J.M.; Lockwood, D.H.

1981-01-01

Six overweight adult subjects given a low calorie diet containing adequate amounts of nitrogen but subnormal amounts of potassium (K) were observed on the Clinical Research Center for periods of 29 to 40 days. Metabolic balance of potassium was measured together with frequent assays of total body K by 40 K counting. Metabolic K balance underestimated body K losses by 11 to 87% (average 43%): the intersubject variability is such as to preclude the use of a single correction value for unmeasured losses in K balance studies
Interaction between Single Nucleotide Polymorphism and Urinary Sodium, Potassium, and Sodium-Potassium Ratio on the Risk of Hypertension in Korean Adults

Directory of Open Access Journals (Sweden)

Yeong Mi Park

2017-03-01

Full Text Available Hypertension is a complex disease explained with diverse factors including environmental factors and genetic factors. The objectives of this study were to determine the interaction effects between gene variants and 24 h estimated urinary sodium and potassium excretion and sodium-potassium excretion ratios on the risk of hypertension. A total of 8839 participants were included in the genome-wide association study (GWAS to find genetic factors associated with hypertension. Tanaka and Kawasaki formulas were applied to estimate 24 h urinary sodium and potassium excretion. A total of 4414 participants were included in interaction analyses to identify the interaction effects of gene variants according to 24 h estimated urinary factors on the risk of hypertension. CSK rs1378942 and CSK-MIR4513 rs3784789 were significantly modified by urinary sodium-potassium excretion ratio. In addition, MKLN rs1643270 with urinary potassium excretion, LOC101929750 rs7554672 with urinary sodium and potassium excretion, and TENM4 rs10466739 with urinary sodium-potassium excretion ratio showed significant interaction effects. The present study results indicated that the mutant alleles of CSK rs1378942 and CSK-MIR4513 rs3784789 had the strongest protective effects against hypertension in the middle group of 24 h estimated urinary sodium-potassium excretion ratio. Further studies are needed to replicate these analyses in other populations.
Potassium sorbate-A new aqueous copper corrosion inhibitor

International Nuclear Information System (INIS)

Abelev, Esta; Starosvetsky, David; Ein-Eli, Yair

2007-01-01

This work presents the novel nature of 2,4-hexadienoic acid potassium salt (potassium sorbate (KCH 3 CH=CHCH=CHCO 2 )) as an effective copper aqueous corrosion inhibitor. The influence of pH and potassium sorbate concentration on copper corrosion in aerated sulfate and chloride solutions is reported. Degree of copper protection was found to increase with an increase in potassium sorbate concentration; an optimum concentration of this inhibitor in sulfate solutions was found to be 10 g/L. Copper is highly resistant to corrosion attacks by chloride ions in the presence of potassium sorbate. X-ray photoelectron spectroscopy (XPS) studies suggest that copper protection is achieved via the formation of a mixed layer of cuprous oxide, cupric hydroxide and copper(II)-sorbate at the metal surface
Gold prices

OpenAIRE

Joseph G. Haubrich

1998-01-01

The price of gold commands attention because it serves as an indicator of general price stability or inflation. But gold is also a commodity, used in jewelry and by industry, so demand and supply affect its pricing and need to be considered when gold is a factor in monetary policy decisions.
Microinjection study on potassium transport of rat kidney

International Nuclear Information System (INIS)

Miyamoto, Makoto

1978-01-01

Wister rate were divided into the following four groups. (A) control group (B) high-potassium diet group (C) low-potassium diet group (D) nephron population reduction (N.P.R.) group. Microinjection of the artificial solutions containing both 86 Rb and 3 H-inulin were performed into the proximal and distal convoluted tubules as well as cortical peritubular capillaries in rats undergoing mannitol diuresis. Excretory patterns of these substances were analyzed in successive urine samples. 3 H-inulin is entirely recovered in the urine of the experimental kidney following the injection into the proximal and distal tubules. 86 Rb is an adequate tracer for potassium and is absorbed into the potassium pool from either proximal tubular injections or peritubular capillaries. 86 Rb excreted with a time course similar to that of 3 H-inulin is termed as 'direct recovery' and that excreted more slowly, 'delayed recovery'. The 86 Rb recoveries which were obtained after proximal injections were independent of the injection site and averaged 9%. Secretion of 86 Rb into the urine was stimulate during enhanced K secretion and decreased during reduced K secretion along the distal nephron. Distal tubular injections gave 100% direct recovery in control, high-K diet, and N.P.R. rats. It was apparent that the 86 Rb recovery was significantly reduced, although not delayed, in animals deprived of dietary potassium for several weeks. At the collecting duct, the extensive net potassium reabsorption is observed in potassium depleted rats, whereas K absorption might be reduced or even secretion is seemingly taking place in potassium loading rats. In conclution, distal convolution and collecting duct play the major role in the regulation of urinary potassium excretion. (auth.)
21 CFR 172.375 - Potassium iodide.

Science.gov (United States)

2010-04-01

... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) FOOD ADDITIVES PERMITTED FOR DIRECT ADDITION TO FOOD FOR HUMAN CONSUMPTION Special Dietary and Nutritional Additives § 172.375 Potassium iodide. The food additive potassium iodide may be...

Yeast Kch1 and Kch2 membrane proteins play a pleiotropic role in membrane potential establishment and monovalent cation homeostasis regulation

Czech Academy of Sciences Publication Activity Database

Felcmanová, Kristina; Nevečeřalová, Petra; Sychrová, Hana; Zimmermannová, Olga

2017-01-01

Roč. 17, č. 5 (2017), č. článku fox053. ISSN 1567-1356 R&D Projects: GA ČR(CZ) GA16-03398S; GA MŠk(CZ) LH14297 Institutional support: RVO:67985823 Keywords : Kch proteins * plasma-membrane potential * monovalent cation homeostasis * intracellular pH * Saccharomyces cerevisiae * Candida albicans Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Mycology Impact factor: 3.299, year: 2016
Potassium Iodide

Science.gov (United States)

... certain other liquids including low-fat white or chocolate milk, flat soda, orange juice, raspberry syrup, or ... Potassium iodide may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away: swollen glands metallic taste in the ...
Effects of extracellular potassium diffusion on electrically coupled neuron networks

Science.gov (United States)

Wu, Xing-Xing; Shuai, Jianwei

2015-02-01

Potassium accumulation and diffusion during neuronal epileptiform activity have been observed experimentally, and potassium lateral diffusion has been suggested to play an important role in nonsynaptic neuron networks. We adopt a hippocampal CA1 pyramidal neuron network in a zero-calcium condition to better understand the influence of extracellular potassium dynamics on the stimulus-induced activity. The potassium concentration in the interstitial space for each neuron is regulated by potassium currents, Na+-K+ pumps, glial buffering, and ion diffusion. In addition to potassium diffusion, nearby neurons are also coupled through gap junctions. Our results reveal that the latency of the first spike responding to stimulus monotonically decreases with increasing gap-junction conductance but is insensitive to potassium diffusive coupling. The duration of network oscillations shows a bell-like shape with increasing potassium diffusive coupling at weak gap-junction coupling. For modest electrical coupling, there is an optimal K+ diffusion strength, at which the flow of potassium ions among the network neurons appropriately modulates interstitial potassium concentrations in a degree that provides the most favorable environment for the generation and continuance of the action potential waves in the network.
Benefit and risk assessment of increasing potassium intake by replacement of sodium chloride with potassium chloride in industrial food products in Norway.

Science.gov (United States)

Steffensen, Inger-Lise; Frølich, Wenche; Dahl, Knut Helkås; Iversen, Per Ole; Lyche, Jan Ludvig; Lillegaard, Inger Therese Laugsand; Alexander, Jan

2018-01-01

High sodium chloride (NaCl) intake is associated with health risks. NaCl may be replaced by potassium chloride (KCl) to decrease sodium intake. However, increased potassium may also have negative health effects. We conducted a benefit and risk assessment of increasing potassium by ratios of 30:70, 50:50, 70:30 (weight % K + : weight % Na + ) in children, adolescents and adults in Norway, using intake data from national food consumption surveys and available literature on potassium health effects. An intake of at least 3.5 g/day of potassium decreases risk of stroke and hypertension, and this level was used in the benefit assessment of the healthy population. Three g/day of potassium added to mean food intake is assumed safe, and these levels were used in the risk assessment. Not all persons reached the protective level of potassium, and increasing numbers exceeded the safe levels, in these scenarios. In addition, elderly above 85 years and infants below one year of age, as well as several patient groups and medication users, are particularly vulnerable to hyperkalemia. In conclusion, the number of Norwegians facing increased risk is far greater than the number likely to benefit from this replacement of sodium with potassium in industrially produced food. Copyright © 2017 Elsevier Ltd. All rights reserved.
Lack of genotoxicity of potassium iodate in the alkaline comet assay and in the cytokinesis-block micronucleus test. Comparison to potassium bromate.

Science.gov (United States)

Poul, J M; Huet, S; Godard, T; Sanders, P

2004-02-01

Iodine could be added to the diet of human population in the form of iodide or iodate but iodate had not been adequately tested for genotoxicity and carcinogenicity. In the present study, genotoxic effects of potassium iodate were evaluated in vitro using the alkaline comet assay and the cytokinesis-block micronucleus assay on CHO cells and compared to halogenate salt analogues potassium bromate and chlorate and also to their respective reduced forms (potassium iodide, bromide and chloride). The results showed that the comet assay failed to detect the presence of DNA damage after a treatment of cells by potassium iodate for concentrations up to 10 mM. This absence of primary DNA damage was confirmed in the cytokinesis-block micronucleus assay. In the same way, results showed that potassium chlorate as well as potassium iodide, bromide and chloride did not induced DNA damage in the alkaline comet assay for doses up to 10 mM. By contrast, potassium bromate exposure led to an increase in both DNA damage and frequency of micronucleated cells. The repair of bromate-induced DNA damage was incomplete 24 h after the end of treatment. These results seem to indicate that potassium bromate would induce DNA damage by several mechanisms besides oxidative stress.
Multistability in a neuron model with extracellular potassium dynamics

Science.gov (United States)

Wu, Xing-Xing; Shuai, J. W.

2012-06-01

Experiments show a primary role of extracellular potassium concentrations in neuronal hyperexcitability and in the generation of epileptiform bursting and depolarization blocks without synaptic mechanisms. We adopt a physiologically relevant hippocampal CA1 neuron model in a zero-calcium condition to better understand the function of extracellular potassium in neuronal seizurelike activities. The model neuron is surrounded by interstitial space in which potassium ions are able to accumulate. Potassium currents, Na+-K+ pumps, glial buffering, and ion diffusion are regulatory mechanisms of extracellular potassium. We also consider a reduced model with a fixed potassium concentration. The bifurcation structure and spiking frequency of the two models are studied. We show that, besides hyperexcitability and bursting pattern modulation, the potassium dynamics can induce not only bistability but also tristability of different firing patterns. Our results reveal the emergence of the complex behavior of multistability due to the dynamical [K+]o modulation on neuronal activities.
Altered potassium homeostasis in Crohn's disease

International Nuclear Information System (INIS)

Schober, O.; Hundeshagen, H.; Bosaller, C.; Lehr, L.

1983-01-01

The total body potassium (TBK), serum potassium, and the number of red blood cell ouabain-binding sites was studied in 94 patients with Crohn's diease. TBK was measured by counting the endogenous 40 K in a whole body counter. TBK was 87%+-13% in 94 patients was Crohn's disease, while in control subjects, it was 97%+-12% (n=24). This significant reduction in TBK was accompanied by normal serum potassium levels (4.4+-0.5 mM). TBK was significantly correlated with the Crohn's disease activity index (r=0.79, n=113, P 3 H-ouabain showed a significant increse in the number of Na-K pumps in Crohn's disease (396+-65, n=27) compared with the control group. 290+-45 (n=24). These results support the suggestion that changes in TBK may regulate the synthesis of Na-K pump molecules. The total body potassium depletion and the need for a preoperative nutritional support in Crohn's disease are discussed. (orig.)
Computational study on potassium picrate crystal

Energy Technology Data Exchange (ETDEWEB)

Ju, Xue-Hai; Lu, Ya-Lin; Ma, Xiu-Fang; Xiao, He-Ming [Department of Chemistry, Nanjing University of Science and Technology, Nanjing, 210094 (China)

2006-08-15

DFT calculation at the B3LYP level was performed on crystalline potassium picrate. The frontier bands are slightly fluctuant. The energy gap between the highest occupied crystal orbital (HOCO) and the lowest unoccupied crystal orbital (LUCO) is 0.121 a.u. (3.29 eV). The carbon atoms that are connected with the nitro groups make up the narrow lower energy bands, with small contributions from nitro oxygen and phenol oxygen. The higher energy bands consist of orbitals from the nitro groups and carbon atom. The potassium bears almost 1 a.u. positive charge. The potassium forms ionic bonding with the phenol oxygen and the nitro oxygen at the same time. The crystal lattice energy is predicted to be -574.40 kJ/mol at the B3LYP level determined with the effective core pseudopotential HAYWSC-31G basis set for potassium and 6-31G** basis set for other atoms. (Abstract Copyright [2006], Wiley Periodicals, Inc.)
Uses of the potassium permanganate to eliminate copper cyanide from waste water resulting from a lixiviation plant in a gold mine (I); Aplicacion del permanganato potasico para la eliminacion de cianuros de cobre en aguas residuales de la planta de lixiviacion en una mina de oro (I)

Energy Technology Data Exchange (ETDEWEB)

Sancho, J. P.; Fernandez, B.; Ayala, J.; Garcia, M. P.; Lavandeira, A.

2009-07-01

The use of cyanide in the hydrometallurgical and chemical industries has led to the emergence of a major environmental problem due to its high toxicity. Te wastewater generated at these plants is hazardous to the environment and therefore must be managed properly. For this purpose, they undergo detoxification processes after lodes from the plant are accumulated in waste-resistant containment ponds that mast be waterproof to prevent environmental disasters from leakages or massive flood. This work shows the results obtained in laboratory tests carried out with plant waters and demonstrates the efficacy of potassium permanganate as an oxidant of cyanide wastewater from a gold hydrometallurgical plant. In the process the destruction of the copper cyanide complexes is solution is achieved and copper metal ions are eliminated through precipitation mostly as hydroxide. (Author) 28 refs.
Suicidal Ingestion of Potassium Permanganate Crystals: A Rare Encounter

OpenAIRE

Karthik, Ravikanti; Veerendranath, Hari Prasad Kanakapura; Wali, Siddraj; Mohan, Murali N T; Kumar, Praveen A. C.; Trimurty, Gaganam

2014-01-01

Potassium permanganate poisoning is not common. Although Symptoms of potassium permanganate ingestion are gastrointestinal and Complications due to ingestion of potassium permanganate include cardiovascular depression, hepatic and renal damage, upper airway obstruction, bleeding tendency and methemoglobinemia. Gastric damage due to potassium permanganate has rarely been reported previously. We are reporting a 34-year old female patient who presented to our Emergency Department after suicidal ...
Potassium Blood Test

Science.gov (United States)

... K. Brunner & Suddarth's Handbook of Laboratory and Diagnostic Tests. 2 nd Ed, Kindle. Philadelphia: Wolters Kluwer Health, Lippincott Williams & Wilkins; c2014. Potassium, Serum; 426–27 p. Lab ...
Adaptation of Bacillus subtilis to Life at Extreme Potassium Limitation.

Science.gov (United States)

Gundlach, Jan; Herzberg, Christina; Hertel, Dietrich; Thürmer, Andrea; Daniel, Rolf; Link, Hannes; Stülke, Jörg

2017-07-05

Potassium is the most abundant metal ion in every living cell. This ion is essential due to its requirement for the activity of the ribosome and many enzymes but also because of its role in buffering the negative charge of nucleic acids. As the external concentrations of potassium are usually low, efficient uptake and intracellular enrichment of the ion is necessary. The Gram-positive bacterium Bacillus subtilis possesses three transporters for potassium, KtrAB, KtrCD, and the recently discovered KimA. In the absence of the high-affinity transporters KtrAB and KimA, the bacteria were unable to grow at low potassium concentrations. However, we observed the appearance of suppressor mutants that were able to overcome the potassium limitation. All these suppressor mutations affected amino acid metabolism, particularly arginine biosynthesis. In the mutants, the intracellular levels of ornithine, citrulline, and arginine were strongly increased, suggesting that these amino acids can partially substitute for potassium. This was confirmed by the observation that the supplementation with positively charged amino acids allows growth of B. subtilis even at the extreme potassium limitation that the bacteria experience if no potassium is added to the medium. In addition, a second class of suppressor mutations allowed growth at extreme potassium limitation. These mutations result in increased expression of KtrAB, the potassium transporter with the highest affinity and therefore allow the acquisition and accumulation of the smallest amounts of potassium ions from the environment. IMPORTANCE Potassium is essential for every living cell as it is required for the activity for many enzymes and for maintaining the intracellular pH by buffering the negative charge of the nucleic acids. We have studied the adaptation of the soil bacterium Bacillus subtilis to life at low potassium concentrations. If the major high-affinity transporters are missing, the bacteria are unable to grow
Potassium acceptor doping of ZnO crystals

Directory of Open Access Journals (Sweden)

Narendra S. Parmar

2015-05-01

Full Text Available ZnO bulk single crystals were doped with potassium by diffusion at 950°C. Positron annihilation spectroscopy confirms the filling of zinc vacancies and a different trapping center for positrons. Secondary ion mass spectroscopy measurements show the diffusion of potassium up to 10 μm with concentration ∼1 × 1016 cm−3. IR measurements show a local vibrational mode (LVM at 3226 cm−1, at a temperature of 9 K, in a potassium doped sample that was subsequently hydrogenated. The LVM is attributed to an O–H bond-stretching mode adjacent to a potassium acceptor. When deuterium substitutes for hydrogen, a peak is observed at 2378 cm−1. The O-H peak is much broader than the O-D peak, perhaps due to an unusually low vibrational lifetime. The isotopic frequency ratio is similar to values found in other hydrogen complexes. Potassium doping increases the resistivity up to 3 orders of magnitude at room temperature. The doped sample has a donor level at 0.30 eV.
Potassium acceptor doping of ZnO crystals

Science.gov (United States)

Parmar, Narendra S.; Corolewski, Caleb D.; McCluskey, Matthew D.; Lynn, K. G.

2015-05-01

ZnO bulk single crystals were doped with potassium by diffusion at 950°C. Positron annihilation spectroscopy confirms the filling of zinc vacancies and a different trapping center for positrons. Secondary ion mass spectroscopy measurements show the diffusion of potassium up to 10 μm with concentration ˜1 × 1016 cm-3. IR measurements show a local vibrational mode (LVM) at 3226 cm-1, at a temperature of 9 K, in a potassium doped sample that was subsequently hydrogenated. The LVM is attributed to an O-H bond-stretching mode adjacent to a potassium acceptor. When deuterium substitutes for hydrogen, a peak is observed at 2378 cm-1. The O-H peak is much broader than the O-D peak, perhaps due to an unusually low vibrational lifetime. The isotopic frequency ratio is similar to values found in other hydrogen complexes. Potassium doping increases the resistivity up to 3 orders of magnitude at room temperature. The doped sample has a donor level at 0.30 eV.
Potassium acceptor doping of ZnO crystals

Energy Technology Data Exchange (ETDEWEB)

Parmar, Narendra S., E-mail: nparmar@wsu.edu; Lynn, K. G. [Center for Materials Research, Washington State University, Pullman, Washington 99164-2711 (United States); Department of Physics and Astronomy, Washington State University, Pullman, Washington 99164-2814 (United States); Corolewski, Caleb D.; McCluskey, Matthew D. [Department of Physics and Astronomy, Washington State University, Pullman, Washington 99164-2814 (United States)

2015-05-15

ZnO bulk single crystals were doped with potassium by diffusion at 950°C. Positron annihilation spectroscopy confirms the filling of zinc vacancies and a different trapping center for positrons. Secondary ion mass spectroscopy measurements show the diffusion of potassium up to 10 μm with concentration ∼1 × 10{sup 16} cm{sup −3}. IR measurements show a local vibrational mode (LVM) at 3226 cm{sup −1}, at a temperature of 9 K, in a potassium doped sample that was subsequently hydrogenated. The LVM is attributed to an O–H bond-stretching mode adjacent to a potassium acceptor. When deuterium substitutes for hydrogen, a peak is observed at 2378 cm{sup −1}. The O-H peak is much broader than the O-D peak, perhaps due to an unusually low vibrational lifetime. The isotopic frequency ratio is similar to values found in other hydrogen complexes. Potassium doping increases the resistivity up to 3 orders of magnitude at room temperature. The doped sample has a donor level at 0.30 eV.
Urinary potassium to urinary potassium plus sodium ratio can accurately identify hypovolemia in nephrotic syndrome: a provisional study.

Science.gov (United States)

Keenswijk, Werner; Ilias, Mohamad Ikram; Raes, Ann; Donckerwolcke, Raymond; Walle, Johan Vande

2018-01-01

There is evidence pointing to a decrease of the glomerular filtration rate (GFR) in a subgroup of nephrotic children, likely secondary to hypovolemia. The aim of this study is to validate the use of urinary potassium to the sum of potassium plus sodium ratio (UK/UK+UNa) as an indicator of hypovolemia in nephrotic syndrome, enabling detection of those patients who will benefit from albumin infusion. We prospectively studied 44 nephrotic children and compared different parameters to a control group (36 children). Renal perfusion and glomerular permeability were assessed by measuring clearance of para-aminohippurate and inulin. Vaso-active hormones and urinary sodium and potassium were also measured. Subjects were grouped into low, normal, and high GFR groups. In the low GFR group, significantly lower renal plasma flow (p = 0.01), filtration fraction (p = 0.01), and higher UK/UK+UNa (p = 0.03) ratio were noted. In addition, non-significant higher plasma renin activity (p = 0.11) and aldosteron (p = 0.09) were also seen in the low GFR group. A subgroup of patients in nephrotic syndrome has a decrease in glomerular filtration, apparently related to hypovolemia which likely can be detected by a urinary potassium to potassium plus sodium ratio > 0.5-0.6 suggesting benefit of albumin infusion in this subgroup. What is Known: • Volume status can be difficult to assess based on clinical parameters in nephrotic syndrome, and albumin infusion can be associated with development of pulmonary edema and fluid overload in these patients. What is New: • Urinary potassium to the sum of urinary potassium plus sodium ratio can accurately detect hypovolemia in nephrotic syndrome and thus identify those children who would probably respond to albumin infusion.
Synthesis of oxocarbon-encapsulated gold nanoparticles with blue-shifted localized surface plasmon resonance by pulsed laser ablation in water with CO2 absorbers

Science.gov (United States)

Del Rosso, T.; Rey, N. A.; Rosado, T.; Landi, S.; Larrude, D. G.; Romani, E. C.; Freire Junior, F. L.; Quinteiro, S. M.; Cremona, M.; Aucelio, R. Q.; Margheri, G.; Pandoli, O.

2016-06-01

Colloidal suspensions of oxocarbon-encapsulated gold nanoparticles have been synthesized in a one-step procedure by pulsed-laser ablation (PLA) at 532 nm of a solid gold target placed in aqueous solution containing CO2 absorbers, but without any stabilizing agent. Multi-wavelength surface enhanced Raman spectroscopy allows the identification of adsorbed amorphous carbon and graphite, Au-carbonyl, Au coordinated CO2-derived bicarbonates/carbonates and hydroxyl groups around the AuNPs core. Scanning electron microscopy, energy dispersive x-ray analysis and high resolution transmission electron microscopy highlight the organic shell structure around the crystalline metal core. The stability of the colloidal solution of nanocomposites (NCs) seems to be driven by solvation forces and is achieved only in neutral or basic pH using monovalent hydroxide counter-ions (NaOH, KOH). The NCs are characterized by a blue shift of the localized surface plasmon resonance (LSPR) band typical of metal-ligand stabilization by terminal π-back bonding, attributed to a core charging effect caused by Au-carbonyls. Total organic carbon measurements detect the final content of organic carbon in the colloidal solution of NCs that is about six times higher than the value of the water solution used to perform PLA. The colloidal dispersions of NCs are stable for months and are applied as analytical probes in amino glycoside antibiotic LSPR based sensing.
Gold 100: proceedings of the international conference on gold. V. 2

International Nuclear Information System (INIS)

Fivaz, C.E.; King, R.P.

1986-01-01

The proceedings of Gold 100 have been published in three separate volumes. The first deals with the mining of gold, the second with the extractive metallurgy of gold, and the third with industrial uses of gold. In this second volume, the papers on extractive metallurgy presented at the Conference reflect most of the problems that are currently of significant technical interest to the industry. This volume is divided in six main parts covering plant design, carbon-in-pulp technology, refractory gold, new technology, grinding and concentration, and leaching. The part on new technology includes papers on x-ray fluorescence analyzers, Moessbauer spectroscopy and leaching processes for uranium, while the part on grinding and concentration includes papers on nuclear and radiotracer techniques for the recovery of gold as well as various flotation parameters in the flotation behaviour of gold and uranium
On the fusibility of potassium heptafluorotantalate

International Nuclear Information System (INIS)

Agulyanskij, A.I.; Bessonova, V.A.

1983-01-01

Phase transformations of potassium heptafluorotantalate near the liquidus temperature have been studied. Thermograms and polytherm of the electric condUctivity of potassium heptafluorotantalate, thermogram of the mechanical mixture 0.5 K 2 TaF 7 +0.5 KF and thermogram of K 3 TaF 8 crystallization are plotted. The phase diagram of the K 2 TaF 7 -KF system is presented. In the temperature range 746 to 778 deg, i.e. above K 2 TaF 7 melting point, the melt is shown to remain heterogeneous. A portion of the phase diagram rich in potassium heptafluorotantalate is qualified as an ordinary eutectics
Paper Money but a Gold Debt. Italy in the Gold Standard

OpenAIRE

Giuseppe Tattara; or consequences)

2002-01-01

During the 52 years between the Unification of the Kingdom of Italy and World War 1, the lira was legally convertible into metal for a limited period of time. Although not formally committed to gold, the lira exchange towards the gold standard countries proved remarkably stable, \\223shadowing\\224 gold. It is widely claimed that being one of the successful members of the gold standard circle entailed a number of advantages. If the lira was closely linked to gold, suggesting that there was only...

Intracellular mediators of potassium-induced aldosterone secretion

International Nuclear Information System (INIS)

Ganguly, A.; Chiou, S.; Davis, J.S.

1990-01-01

We have investigated the intracellular messengers of potassium in eliciting aldosterone secretion in calf adrenal glomerulosa cells since there were unresolved issues relating to the role of phosphoinositides, cAMP and protein kinases. We observed no evidence of hydrolysis of phosphatidylinositol 4,5-bisphosphate (PIP 2 ) in 3 H-inositol labeled alf adrenal cells or increase of cAMP in response to potassium. Addition of calcium channel blocker, nitrendipine after stimulating adrenal glomerulosa cells with potassium, markedly inhibited aldosterone secretion. A calmodulin inhibitor (W-7) produced greater reduction of aldosterone secretion than an inhibitor of protein kinase C (H-7). These results suggest that a rise in cytosolic free calcium concentration through voltage-dependent calcium channel and calmodulin are the critical determinants of aldosterone secretion stimulated by potassium
Low potassium level

Science.gov (United States)

... treat and prevent low level of potassium. These foods include: Avocados Baked potato Bananas Bran Carrots Cooked lean beef Milk Oranges Peanut butter Peas and beans Salmon Seaweed Spinach Tomatoes Wheat germ
Polarographic determination of selenium and tellurium in silver-gold alloys

International Nuclear Information System (INIS)

Gornostaeva, T.D.; Shmargun, S.V.

1986-01-01

The determination of selenium and tellurium is of importance in monitoring the composition of silver-gold alloys (SGA) since these elements are harmful impurities in the pure metals. Tellurium is determined in silver alloys by atomic absorption and atomic emmission methods; selenium determination is made by atomic absorption methods. This paper examines the polarographic determination of silver and tellurium in SGA containing platinum metals and copper. Copper and the bulk of the platinum and palladium were removed by precipitating selenium and tellurium with potassium hypophosphite in the elementary state from 6 M HC1. The results of an analysis of samples of SGA according to the proposed method were compared with the results obtained by the atomic absorption method. the relative deviation in the determination of 0.02-1.0% by weight selenium and tellurium does not exceed 0.12 (n = 5)
GOLD IS EARNED FROM THE PRODUCTION OF THAI GOLD LEAF

Directory of Open Access Journals (Sweden)

Dirk Bax

2010-06-01

Full Text Available Thai people like to cover sacred objects or things dear to them with gold leaf.. Statues of Buddha are sometimes covered with so many layers of gold leaf that they become formless figures, that can hardly be recognized. Portraits of beloved ancestors, statues of elephants and grave tombs are often covered with gold leaf. If one considers the number of Thai people and the popularity of the habit, the amount of gold involved could be considerable.
Role of hemolysis in potassium release by iodinated contrast medium

Energy Technology Data Exchange (ETDEWEB)

Hayakawa, K.; Nakamura, T.; Shimizu, Y. [Department of Radiology, Kyoto City Hospital (Japan)

1999-09-01

It has been demonstrated that an iodinated contrast medium (CM) causes release of potassium into blood vessel lumina, resulting in an increase in serum potassium. The purpose of the present study was to assess whether this potassium release is due to hemolysis. Fresh human blood was mixed in vitro with CM at a ratio of 10:2. Potassium release rates were determined, and serum haptoglobin and free hemoglobin were measured after 30 min of exposure to CM. To compare the potassium release curve between CM exposure and true hemolysis induced by distilled water, fresh human blood was also mixed with distilled water. The level of serum haptoglobin decreased due to hemodilution. Changes in haptoglobin were not correlated with potassium release rates. The serum free hemoglobin level did not increase significantly, and there was no correlation between changes in the free hemoglobin level and the rate of potassium release. Hemolysis caused by water occurred instantaneously, whereas potassium release caused by CM was a slow response, which was linearly correlated with exposure time. Potassium release from blood cannot be explained by hemolysis. (orig.) With 4 figs., 4 tabs., 3 refs.
21 CFR 582.1613 - Potassium bicarbonate.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Potassium bicarbonate. 582.1613 Section 582.1613 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE General Purpose Food Additives § 582.1613 Potassium bicarbonate. (a)...
21 CFR 184.1610 - Potassium alginate.

Science.gov (United States)

2010-04-01

...: Category of food Maximum level of use in food (as served) (percent) Functional use Confections and...) of this chapter 0.25 Do. All other food categories 0.01 Do. (d) Prior sanctions for potassium... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Potassium alginate. 184.1610 Section 184.1610 Food...
A novel potassium deficiency-induced stimulon in Anabaena torulosa

Indian Academy of Sciences (India)

Unknown

torulosa and of nine proteins in Escherichia coli. These were termed potassium deficiency-induced proteins or. PDPs and constitute hitherto unknown potassium deficiency–induced stimulons. Potassium deficiency also enhanced the synthesis of certain osmotic stress-induced proteins. Addition of K+ repressed the ...
Genetic Aspects of Gold Mineralization at Some Occurrences in the Eastern Desert of Egypt

Science.gov (United States)

Abd El Monsef, M.; Slobodník, M.; Salem, I. A.

2012-04-01

in each area and revealing the ore mineralogy and the ore textures, geochemical analyses (including rare earth elements) are to be used in order to determine the tectonic setting and magmatic evolution of the host intrusions, scanning electron microscope, microprobe analysis, stable isotopes and fluid inclusions will serve as a new part of this study in detection of the origin and the physico-chemical conditions (P-T condition) for the gold precipitation, Age dating of the host intrusion and mineralization will be based on K-Ar for dating potassium-bearing minerals in fresh host rocks and hydrothermal mineral phases.
21 CFR 862.1600 - Potassium test system.

Science.gov (United States)

2010-04-01

... potassium in serum, plasma, and urine. Measurements obtained by this device are used to monitor electrolyte balance in the diagnosis and treatment of diseases conditions characterized by low or high blood potassium levels. (b) Classification. Class II. ...
Characterization of gold mineralization in Garin Hawal area, Kebbi State, NW Nigeria, using remote sensing

Directory of Open Access Journals (Sweden)

Talaat M. Ramadan

2010-12-01

Full Text Available Garin Hawal area, Kebbi State, NW Nigeria is part of the Neoproterozoic to Early Phanerozoic terrane separating the west African and Congo Cratons. Three main gold-bearing shear zones were detected in the study area from the processed Landsat ETM+ images and extensive ground investigation. Field and petrographical studies indicate that the Neoproterozoic rocks are represented by a highly folded and faulted belt constituted of hornblende, muscovite and graphite schist. They are intruded by granondiorites and late to post granitic dykes. Extensive alteration zones were identified using high resolution QuickBird image along Garin Hawal shear zone. The alteration zones and associated quartz veins are generally concordant with the main NE–SW regional structural trend and are dipping to the NW. Geochemical studies indicate that the gold content reaches 8 g/t in the alteration zones, while it reaches up to 35 g/t in the quartz veins. Mineralogical studies indicate that the alterations are strongly potassium-enriched. Pyrophyllite, kaolinite, illite, gypsum and quartz also occur. The main ore minerals are gold, chalcopyrite, arsenopyrite, pyrite, galena and iron oxides. This study indicates that the alteration zones and the associated quartz veins in the muscovite schist are promising and need more detailed exploration for Au and Ag mineralization to evaluate their potential.
Potassium permanganate-glutaraldehyde chemiluminescence system catalyzed by gold nanoprisms toward selective determination of fluoride.

Science.gov (United States)

Abolhasani, Jafar; Hassanzadeh, Javad; Ghorbani-Kalhor, Ebrahim

2016-02-01

Gold and silver nanoparticles (NPs) are shown to exert a positive effect on the chemiluminescence (CL) reaction of permanganate aldehydes. Interestingly, between various shapes examined, Au nanoprisms have the highest beneficial effect. This effect is even more notable in the presence of sodium dodecyl sulfate (SDS) surfactant. UV-vis spectra and transmission electron microscopy were used to characterize the NP shapes and sizes. Furthermore, it was observed that iron(III) ions can slightly increase CL emission of this system. This intensification is very effective in the presence of fluoride ions (F(-)). These observations form the basis of the method for the high sensitive determination of F(-) in the 6-1200 nmol L(-1) concentration range, with a detection limit of 2.1 nmol L(-1). The proposed method has good precision and was satisfactorily used in the selective determination of low concentrations of fluoride ion in real samples. Copyright © 2015 John Wiley & Sons, Ltd.
Effects of Long-term Fertilization on Potassium Fixation Capacity in Brown Soil

Science.gov (United States)

Li, Na; Guo, Chunlei; Wang, Yue; Gao, Tianyi; Yang, Jinfeng; Han, Xiaori

2018-01-01

This study concentrated on the research of features of fixation. The objective of this study was to provide theoretical foundation of rational application of potassium fertilizer along with improving fertilizer availability ratio. A 32 years long-term experiment was conducted to evaluate the effects of fertilizer application on potassium changes and the factors affecting K fixation on brown soil by simulation in laboratory. When the concentration of exogenous potassium was in range of 400∼4000 mg·kg-1, potassium fixation capacity increased along with the rise of concentration of exogenous potassium, whereas K fixation rate reduced; Compared with no-potassium fertilizer, application of potassium fertilizer and organic fertilizer reduced soil potassium fixation capacity. Potassium rate and fixation-release of potassium character in soil should be taken into comprehensive consideration for rational fertilization to maintain or improve soil fertility for increasing potassium fertilizers efficiency in agriculture.
Robust Multilayer Graphene-Organic Frameworks for Selective Separation of Monovalent Anions.

Science.gov (United States)

Zhao, Yan; Zhu, Jiajie; Li, Jian; Zhao, Zhijuan; Charchalac Ochoa, Sebastian Ignacio; Shen, Jiangnan; Gao, Congjie; Van der Bruggen, Bart

2018-05-30

The chemical and mechanical stability of graphene nanosheets was used in this work to design a multilayer architecture of graphene, grafted with sulfonated 4,4'-diaminodiphenyl sulfone (SDDS). Quaternized poly(phenylene oxide) (QPPO) was synthesized and mixed with SDDS (rGO-SDDS-rGO@QPPO), yielding a multilayer graphene-organic framework (MGOF) with positive as well as negative functional groups that can be applied as a versatile electrodriven membrane in electrodialysis (ED). Multilayer graphene-organic frameworks are a new class of multilayer structures, with an architecture having a tunable interlayer spacing connected by cationic polymer material. MGOF membranes were demonstrated to allow for an excellent selective separation of monovalent anions in aqueous solution. Furthermore, different types of rGO-SDDS-rGO@QPPO membranes were found to have a good mechanical strength, with a tensile strength up to 66.43 MPa. The membrane (rGO-SDDS-rGO@QPPO-2) also has a low surface electric resistance (2.79 Ω·cm 2 ) and a low water content (14.5%) and swelling rate (4.7%). In addition, the selective separation between Cl - and SO 4 2- of the MGOF membranes could be as high as 36.6%.
High potassium level

Science.gov (United States)

... level is very high, or if you have danger signs, such as changes in an ECG . Emergency ... Seifter JL. Potassium disorders. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine . 25th ed. Philadelphia, PA: ...
Dilution thermodynamics of the biologically relevant cation mixtures

International Nuclear Information System (INIS)

Kaczyński, Marek; Borowik, Tomasz; Przybyło, Magda; Langner, Marek

2014-01-01

Graphical abstract: - Highlights: • Dilution energetics of Ca 2+ can be altered by the aqueous phase ionic composition. • Dissipated heat upon Ca 2+ dilution is drastically reduced in the K + presence. • Reduction of the enthalpy change upon Ca 2+ dilution is K + concentration dependent. • The cooperativity of Ca 2+ hydration might be of great biological relevance providing a thermodynamic argument for the specific ionic composition of the intracellular environment. - Abstract: The ionic composition of intracellular space is rigorously controlled by a variety of processes consuming large quantities of energy. Since the energetic efficiency is an important evolutional criterion, therefore the ion fluxes within the cell should be optimized with respect to the accompanying energy consumption. In the paper we present the experimental evidence that the dilution enthalpies of the biologically relevant ions; i.e. calcium and magnesium depend on the presence of monovalent cations; i.e. sodium and potassium. The heat flow generated during the dilution of ionic mixtures was measured with the isothermal titration calorimetry. When calcium was diluted together with potassium the dilution enthalpy was drastically reduced as the function of the potassium concentration present in the solution. No such effect was observed when the potassium ions were substituted with sodium ones. When the dilution of magnesium was investigated the dependence of the dilution enthalpy on the accompanying monovalent cation was much weaker. In order to interpret experimental evidences the ionic cluster formation is postulated. The specific organization of such cluster should depend on ions charges, sizes and organization of the hydration layers
Immunogenicity and safety of monovalent RIVM meningococcal B OMP vesicle F91 vaccine administered to children that received hexavalent meningococcal B vaccine 2.5 years ago

NARCIS (Netherlands)

Lafeber AB; Limpt CJP van; Berbers GAM; Labadie J; Kleijn ED de; Groot R de; Rumke HC; Alphen AJW van; Sophia Kinderziekenhuis /; LVO

2000-01-01

This report describes the results with respect to immunogenicity as well as reactogenicity of a monovalent P1.7h,4 OMV vaccine (MonoMen) used as booster vaccination in children previously vaccinated with a hexavalent MenB vaccine. The participants in this study were immunised in 1995-1996 with
Effects of cisplatin on potassium currents in CT26 cells

Directory of Open Access Journals (Sweden)

Naveen Sharma

2016-01-01

Conclusion: Potassium currents were detected in CT26 cells and the currents were reduced by the application of tetraethylammonium (TEA chloride, iberiotoxin, a big conductance calcium-activated potassium channel blocker and barium. The potassium currents were enhanced to 192< by the application of cisplatin (0.5 mM. Moreover, the increase of potassium currents by cisplatin was further inhibited by the application of TEA confirming the action of cisplatin on potassium channels. In addition, relative current induced by cisplatin in CT26 cells was bit larger than in normal IEC-6 cells.
Enhancement of gold recovery using bioleaching from gold concentrate

Science.gov (United States)

Choi, S. H.; Cho, K. H.; Kim, B. J.; Choi, N. C.; Park, C. Y.

2012-04-01

The gold in refractory ores is encapsulated as fine particles (sometimes at a molecular level) in the crystal structure of the sulfide (typically pyrite with or without arsenopyrite) matrix. This makes it impossible to extract a significant amount of refractory gold by cyanidation since the cyanide solution cannot penetrate the pyrite/arsenopyrite crystals and dissolve gold particles, even after fine grinding. To effectively extract gold from these ores, an oxidative pretreatment is necessary to break down the sulfide matrix. The most popular methods of pretreatment include nitric acid oxidation, roasting, pressure oxidation and biological oxidation by microorganisms. This study investigated the bioleaching efficiency of Au concentrate under batch experimental conditions (adaptation cycles and chemical composition adaptation) using the indigenous acidophilic bacteria collected from gold mine leachate in Sunsin gold mine, Korea. We conducted the batch experiments at two different chemical composition (CuSO4 and ZnSO4), two different adaptation cycles 1'st (3 weeks) and 2'nd (6 weeks). The results showed that the pH in the bacteria inoculating sample decreased than initial condition and Eh increased. In the chemical composition adaptation case, the leached accumulation content of Fe and Pb was exhibited in CuSO4 adaptation bacteria sample more than in ZnSO4 adaptation bacteria samples, possibly due to pre-adaptation effect on chalcopyrite (CuFeS2) in gold concentrate. And after 21 days on the CuSO4 adaptation cycles case, content of Fe and Pb was appeared at 1'st adaptation bacteria sample(Fe - 1.82 and Pb - 25.81 times per control sample) lower than at 2'nd adaptation bacteria sample(Fe - 2.87 and Pb - 62.05 times per control sample). This study indicates that adaptation chemical composition and adaptation cycles can play an important role in bioleaching of gold concentrate in eco-/economic metallurgy process.
Seroprevalence of influenza A H1N1 and seroconversion of mothers and infants induced by a single dose of monovalent vaccine.

Science.gov (United States)

Chao, Anne; Huang, Yhu-Chering; Chang, Yao-Lung; Wang, Tzu-Hao; Chang, Shuenn-Dyh; Wu, Ting-Shu; Wu, Tsu-Lan; Chao, An-Shine

2013-09-01

To determine the prevalence of preexisting antibodies against the pandemic 2009 Influenza A (H1N1) virus in pregnant women and to evaluate the seroprotection of the mothers and infants by a single injection of monovalent vaccine during the pandemic. Seropositivity rate of H1N1 among the nonvaccinated were compared with the vaccinated women. A single dose of vaccine, either nonadjuvanted AdimFlu-S or MF59-adjuvanted vaccine, was injected to the voluntarily vaccinated group. Maternal and cord blood sera were collected to evaluate the antibody response of the H1N1 virus. Seropositivity was defined as a hemagglutination inhibition titer to H1N1 (A/Taiwan/126/09) ≥ 1:40. A total of 210 healthy, singleton, pregnant women were enrolled between January 2010 and May 2010. Seropositivity (≥ 1:40) of maternal hemagglutination inhibition was significantly higher in the vaccinated group (78%) than the nonvaccinated group (9.5%); 41.6% (20/48) of seropositive titers were >1:80. In nine vaccinated cases resulting in negative serum titers (75% could be achieved in the paired maternal and cord serum samples by a single injection of monovalent H1N1 vaccine. Copyright © 2013. Published by Elsevier B.V.

Synthesis and derivatographic investigation of potassium octacyanotungstate (4)

International Nuclear Information System (INIS)

Kovbashin, V.I.; Dovgej, V.V.; Chernyak, B.I.

1983-01-01

The interaction between the rated quantities of potassium cyanide and WO(OH) 3 hydroxide resulted in preparation of potassium dioxytetracyanotungstate (4), K 4 [WO 2 (CN) 4 ]X6H 2 O. The latter, while interacting with a saturated potassium cyanide solution in a carbon dioxide flow transforms to potassium octacyanotungstate (4). The process of K 4 [W(CH) 8 ]x2H 2 O compound thermolysis in argon atmosphere is studied. It is found that, after dehydration of the complex, there occurs thermal transformation of K 4 [W(CN) 8 ] to K 3 [W(CN) 7 ] and then to K 3 [W(CN) 6 ]. The thermolysis final product is tungsten carbide WC
75 FR 23298 - Potassium Permanganate From China

Science.gov (United States)

2010-05-03

... Permanganate From China AGENCY: United States International Trade Commission. ACTION: Institution of a five-year review concerning the antidumping duty order on potassium permanganate from China. SUMMARY: The... on potassium permanganate from China would be likely to lead to continuation or recurrence of...
75 FR 51112 - Potassium Permanganate From China

Science.gov (United States)

2010-08-18

... Permanganate From China AGENCY: United States International Trade Commission. ACTION: Scheduling of an expedited five-year review concerning the antidumping duty order on potassium permanganate from China... of the antidumping duty order on potassium permanganate from China would be likely to lead to...
21 CFR 520.1696d - Penicillin V potassium tablets.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin V potassium tablets. 520.1696d Section... Penicillin V potassium tablets. (a) Specifications. Each tablet contains penicillin V potassium equivalent to 125 milligrams (200,000 units) or 250 milligrams (400,000 units) of penicillin V. (b) Sponsors. See...
Enrichment of Gold in Antimony Matte by Direct Smelting of Refractory Gold Concentrate

Science.gov (United States)

Yang, Tianzu; Xie, Boyi; Liu, Weifeng; Zhang, Duchao; Chen, Lin

2018-06-01

Conventional cyanidation technology achieves low gold recovery when used to process refractory gold concentrate. Based on the geochemical characteristics of gold deposit mineralization, a new method is proposed herein for gold enrichment in antimony matte by smelting of refractory gold concentrate. The effects of the FeO/SiO2 and CaO/SiO2 ratios, smelting temperature, and smelting time on the gold recovery were investigated in detail. The optimum conditions were determined to be FeO/SiO2 ratio of 1.2, CaO/SiO2 ratio of 0.4, smelting temperature of 1200°C, and smelting time of 45 min. The gold content in antimony matte and smelting slag was 96.68 and 1.13 g/t, respectively. The gold, antimony, and arsenic recovery was 97.72%, 26.89%, and 6.56%, respectively, with most of the antimony and arsenic volatilized into dust. Mineral liberation analyzer results showed that the antimony matte mainly consisted of FeS and FeO, with three phases, viz. FeAs, SbAs, and AuSb, embedded between them, indicating that gold was easily enriched with antimony and arsenic during smelting of refractory gold concentrate.
Enrichment of Gold in Antimony Matte by Direct Smelting of Refractory Gold Concentrate

Science.gov (United States)

Yang, Tianzu; Xie, Boyi; Liu, Weifeng; Zhang, Duchao; Chen, Lin

2018-04-01

Conventional cyanidation technology achieves low gold recovery when used to process refractory gold concentrate. Based on the geochemical characteristics of gold deposit mineralization, a new method is proposed herein for gold enrichment in antimony matte by smelting of refractory gold concentrate. The effects of the FeO/SiO2 and CaO/SiO2 ratios, smelting temperature, and smelting time on the gold recovery were investigated in detail. The optimum conditions were determined to be FeO/SiO2 ratio of 1.2, CaO/SiO2 ratio of 0.4, smelting temperature of 1200°C, and smelting time of 45 min. The gold content in antimony matte and smelting slag was 96.68 and 1.13 g/t, respectively. The gold, antimony, and arsenic recovery was 97.72%, 26.89%, and 6.56%, respectively, with most of the antimony and arsenic volatilized into dust. Mineral liberation analyzer results showed that the antimony matte mainly consisted of FeS and FeO, with three phases, viz. FeAs, SbAs, and AuSb, embedded between them, indicating that gold was easily enriched with antimony and arsenic during smelting of refractory gold concentrate.
Regulation of extrarenal potassium homeostasis by adrenal hormones in rats.

Science.gov (United States)

Bia, M J; Tyler, K A; DeFronzo, R A

1982-06-01

The effect of chronic (7-10 days) adrenal insufficiency on extrarenal potassium tolerance was examined by infusing potassium into rats after acute nephrectomy. The increment in plasma potassium concentration was significantly higher in glucocorticoid-replaced adrenalectomized rats versus controls (max delta PK 3.59 +/-0.11 vs. 2.93 +/- 0.08 meq/liter; P less than 0.001). The impairment in extrarenal potassium tolerance in adrenalectomized rats could not be attributed to acidemia, hypotension, changes in plasma insulin or glucose concentration, or potassium retention prior to study. Acute replacement with aldosterone resulted in significant improvement in the rise in plasma potassium after KCl (max delta PK 3.18 +/- 0.06 meq/liter; P less than 0.005 compared with aldosterone-deficient adrenalectomized rats but higher than in controls, P less than 0.02). If given on a chronic basis, aldosterone replacement led to a complete correction of the defect (max delta PK = 2.89 +/- 0.08 meq/liter). Acute epinephrine replacement in adrenalectomized rats also returned potassium tolerance to normal (max delta PK = 3.02 +/- 0.10 meq/liter). The results demonstrate that extrarenal potassium tolerance is impaired in chronic adrenal insufficiency and suggest that both aldosterone and epinephrine deficiency may contribute to the defect, since replacement with either hormone returns potassium tolerance toward normal. Accordingly, both aldosterone and epinephrine have important extrarenal mechanisms of action.
Possible potassium chlorate nephrotoxicity associated with chronic matchstick ingestion.

Science.gov (United States)

Thurlow, John S; Little, Dustin J; Baker, Thomas P; Yuan, Christina M

2013-06-01

We present a case of a 48-year-old active duty male soldier with a history of chronic exposure to potassium chlorate, later diagnosed with chronic interstitial nephritis. He reported regular matchstick consumption to prevent chigger (Trombicula autumnalis) bites, amounting to ∼5.8 g of potassium chlorate over 3 years. Potassium chlorate can cause anuric renal failure within days of a toxic dose. Its slow excretion and mechanism of action suggest that renal toxicity may result from lower-dose chronic exposure. This case represents possible sequelae of chronic potassium chlorate ingestion.
Possible potassium chlorate nephrotoxicity associated with chronic matchstick ingestion*

Science.gov (United States)

Thurlow, John S.; Little, Dustin J.; Baker, Thomas P.; Yuan, Christina M.

2013-01-01

We present a case of a 48-year-old active duty male soldier with a history of chronic exposure to potassium chlorate, later diagnosed with chronic interstitial nephritis. He reported regular matchstick consumption to prevent chigger (Trombicula autumnalis) bites, amounting to ∼5.8 g of potassium chlorate over 3 years. Potassium chlorate can cause anuric renal failure within days of a toxic dose. Its slow excretion and mechanism of action suggest that renal toxicity may result from lower-dose chronic exposure. This case represents possible sequelae of chronic potassium chlorate ingestion. PMID:26064493
The geology of the gold deposits of Prestea gold belt of Ghana ...

African Journals Online (AJOL)

This paper presents the geology of the gold deposits along the Prestea gold belt of Ghana to assist exploration work for new orebodies along the belt. Prestea district is the third largest gold producer in West Africa after Obuasi and Tarkwa districts (over 250 metric tonnes Au during the last century). The gold deposits are ...
21 CFR 181.33 - Sodium nitrate and potassium nitrate.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium nitrate and potassium nitrate. 181.33...-Sanctioned Food Ingredients § 181.33 Sodium nitrate and potassium nitrate. Sodium nitrate and potassium nitrate are subject to prior sanctions issued by the U.S. Department of Agriculture for use as sources of...
Gold Leaching Characteristics and Intensification of a High S and As-Bearing Gold Concentrate

Science.gov (United States)

Yang, Yong-bin; Liu, Xiao-liang; Jiang, Tao; Li, Qian; Xu, Bin; Zhang, Yan

Some high sulfur and arsenic-bearing gold concentrate has a gold leaching rate less than 80% by oxidation roasting-pickling-cyanidation process. The characteristics and intensification of gold leaching were studied systemically. By combining chemical composition and phase analysis, the low gold leaching rate was found to lie in the capsulation of gold by iron-containing phases including iron oxides, arsenopyrite and pyrite. 96.66% of gold in the industrial leaching residue was capsulated and 95.88% of the capsulated turned out to be in the iron-containing phases. The results of laboratory pickling-cyanidation experiments on the calcine and industrial leaching residue presented further demonstration for the fact that gold capsulated in the iron-containing phases was hard to be leached. However, the gold cyanide leaching rate of calcine could be raised over 95% by a reduction roasting-pickling pretreatment which played such a significant role in exposing the capsulated gold that gold leaching was intensified remarkably.
Oxidation state of gold and arsenic in gold-bearing arsenian pyrite

Energy Technology Data Exchange (ETDEWEB)

Simon, G.; Huang, H.; Penner-Hahn, J.E.; Kesler, S.E.; Kao, L.S. [Univ. of Michigan, Ann Arbor, MI (United States)

1999-07-01

XANES measurements on gold-bearing arsenian pyrite from the Twin Creeks Carlin-type gold deposits show that gold is present as both Au{sup 0} and Au{sup 1+} and arsenic is present as As{sup 1{minus}}. Au{sup 0} is attributed to sub-micrometer size inclusions of free gold, whereas Au{sup 1+} is attributed to gold in the lattice of the arsenian pyrite. STEM observations suggest that As{sup 1{minus}} is probably concentrated in angstrom-scale, randomly distributed layers with a marcasite or arsenopyrite structure. Ionic gold (Au{sup 1+}) could be concentrated in these layers as well, and is present in both twofold- and fourfold-coordinated forms, with fourfold-coordinated Au{sup 1+} more abundant. Twofold-coordinated Au{sup 1+} is similar to gold in Au{sub 2}S in which it is linearly coordinated to two sulfur atoms. The nature of fourfold-coordinated Au{sup 1+} is not well understood, although it might be present as an Au-As-S compound where gold is bonded in fourfold coordination to sulfur and arsenic atoms, or in vacancy positions on a cation site in the arsenian pyrite. Au{sup 1+} was probably incorporated into arsenian pyrite by adsorption onto pyrite surfaces during crystal growth. The most likely compound in the case of twofold-coordinated Au{sup 1+} was probably a tri-atomic surface complex such as S{sub pyrite}-Au{sup 1+}-S{sub bi-sulfide}H or Au{sup 1+}-S-Au{sup 1+}. The correlation between gold and arsenic might be related to the role of arsenic in enhancing the adsorption of gold complexes of this type on pyrite surfaces, possibly through semiconductor effects.
Evaluating Status Change of Soil Potassium from Path Model

Science.gov (United States)

He, Wenming; Chen, Fang

2013-01-01

The purpose of this study is to determine critical environmental parameters of soil K availability and to quantify those contributors by using a proposed path model. In this study, plot experiments were designed into different treatments, and soil samples were collected and further analyzed in laboratory to investigate soil properties influence on soil potassium forms (water soluble K, exchangeable K, non-exchangeable K). Furthermore, path analysis based on proposed path model was carried out to evaluate the relationship between potassium forms and soil properties. Research findings were achieved as followings. Firstly, key direct factors were soil S, ratio of sodium-potassium (Na/K), the chemical index of alteration (CIA), Soil Organic Matter in soil solution (SOM), Na and total nitrogen in soil solution (TN), and key indirect factors were Carbonate (CO3), Mg, pH, Na, S, and SOM. Secondly, path model can effectively determine direction and quantities of potassium status changes between Exchangeable potassium (eK), Non-exchangeable potassium (neK) and water-soluble potassium (wsK) under influences of specific environmental parameters. In reversible equilibrium state of , K balance state was inclined to be moved into β and χ directions in treatments of potassium shortage. However in reversible equilibrium of , K balance state was inclined to be moved into θ and λ directions in treatments of water shortage. Results showed that the proposed path model was able to quantitatively disclose moving direction of K status and quantify its equilibrium threshold. It provided a theoretical and practical basis for scientific and effective fertilization in agricultural plants growth. PMID:24204659
Potassium Silicate Foliar Fertilizer Grade from Geothermal Sludge and Pyrophyllite

Directory of Open Access Journals (Sweden)

Muljani Srie

2016-01-01

Full Text Available Potassium silicate fertilizer grade were successfully produced by direct fusion of silica (SiO2 and potasium (KOH and K2CO3 in furnaces at temperatures up to melting point of mixture. The geothermal sludge (98% SiO2 and the pyrophyllite (95% SiO2 were used as silica sources. The purposes of the study was to synthesise potassium silicate fertilizer grade having solids concentrations in the range of 31-37% K2O, and silica in the range of 48-54% SiO2. The weight ratio of silicon dioxide/potasium solid being 1:1 to 5:1. Silica from geothermal sludge is amorphous, whereas pyrophylite is crystalline phase. The results showed that the amount of raw materials needed to get the appropriate molar ratio of potassium silicate fertilizer grade are different, as well as the fusion temperature of the furnace. Potassium silicate prepared from potassium hydroxide and geothermal sludge produced a low molar ratio (2.5: 1 to 3: 1. The potassium required quite small (4:1 in weight ratio, and on a fusion temperature of about 900 °C. Meanwhile, the potassium silicate prepared from pyrophyllite produced a high molar ratio (1.4 - 9.4 and on a fusion temperature of about 1350 °C, so that potassium needed large enough to meet the required molar ratio for the fertilizer grade. The product potassium silicate solid is amorphous with a little trace of crystalline.
Near-UV sensitized 1.06 μm emission of Nd{sup 3+} ions via monovalent copper in phosphate glass

Energy Technology Data Exchange (ETDEWEB)

Jiménez, José A., E-mail: jose.jimenez@unf.edu [Department of Chemistry, University of North Florida, Jacksonville, FL 32224 (United States); Sendova, Mariana [Optical Spectroscopy & Nano-Materials Lab, New College of Florida, Sarasota, FL 34243 (United States)

2015-07-15

Monovalent copper ions effectively incorporated in Nd-containing phosphate glass by a single-step melt-quench method have been established as near-ultraviolet (UV) sensitizers of Nd{sup 3+} ions, resulting in a remarkable {sup 4}F{sub 3/2} → {sup 4}I{sub 11/2} emission at 1.06 μm. The spectroscopic data indicates an efficient energy conversion process. The Cu{sup +} ions first absorb photons broadly around 360 nm, and subsequently transfer the energy from the Stokes-shifted emitting states to resonant Nd{sup 3+} energy levels in the visible. Ultimately, the Nd{sup 3+} electronic excited states decay and the upper lasing state {sup 4}F{sub 3/2} is populated, leading to the enhanced emission at 1.06 μm. The characteristic features of the Cu{sup +} visible emission spectra and the reduced lifetime of the corresponding Cu{sup +} donor states indicate an efficient non-radiative transfer. The Cu{sup +}/Nd{sup 3+} co-doped phosphate glass appears suitable as solid-state laser material with enhanced pump range in the near-UV part of the spectrum and for solar spectral conversion in photovoltaic cells. - Graphical abstract: Display Omitted - Highlights: • Monovalent copper ions effectively stabilized in Nd{sup 3+}-containing phosphate glass. • Enhanced Nd{sup 3+} near-infrared emission observed upon the Cu{sup +} ions incorporation. • Cu{sup +} → Nd{sup 3+} non-radiative energy transfer efficiencies and likely energy transfer pathways evaluated. • Potential for solid-state lasers and solar spectral conversion suggested.
Use of potassium-42 in the study of kidney functioning

International Nuclear Information System (INIS)

Morel, F.; Guinnebault, M.

1959-01-01

Following an intravenous injection of potassium-42 as indicator, an analysis of the specific activity vs. time curve in arterial plasma, in venous plasma efferent from the kidney, in urine and in various regions of the kidney of rabbits reveals that: 1) The turnover rate of potassium in the cortex cells (proximal and distal convoluted tubes) is very large, being limited only by renal blood flow. 2) The turnover rate of potassium in deep regions (Henle loops and collector tubules) is much smaller. 3) Potassium in the urine comes from cells of the convoluted tubes and not from cells of Henle loops, collector ducts, or glomerular filtrate. 4) Any potassium filtered at the level of the glomerules would be entirely reabsorbed at the level of the proximal tube, while total potassium in the urine results from a process of excretion by cells of the distal tube. These results are comparable with the assumption that the movement of potassium between interstitial medium and convoluted tube cells results from entirely passive processes. (author) [fr
Higher cytotoxicity of divalent antibody-toxins than monovalent antibody-toxins

International Nuclear Information System (INIS)

Won, JaeSeon; Nam, PilWon; Lee, YongChan; Choe, MuHyeon

2009-01-01

Recombinant antibody-toxins are constructed via the fusion of a 'carcinoma-specific' antibody fragment to a toxin. Due to the high affinity and high selectivity of the antibody fragments, antibody-toxins can bind to surface antigens on cancer cells and kill them without harming normal cells [L.H. Pai, J.K. Batra, D.J. FitzGerald, M.C. Willingham, I. Pastan, Anti-tumor activities of immunotoxins made of monoclonal antibody B3 and various forms of Pseudomonas exotoxin, Proc. Natl. Acad. Sci. USA 88 (1991) 3358-3362]. In this study, we constructed the antibody-toxin, Fab-SWn-PE38, with SWn (n = 3, 6, 9) sequences containing n-time repeated (G 4 S) between the Fab fragment and PE38 (38 kDa truncated form of Pseudomonas exotoxin A). The SWn sequence also harbored one cysteine residue that could form a disulfide bridge between two Fab-SWn-PE38 monomers. We assessed the cytotoxicity of the monovalent (Fab-SWn-PE38), and divalent ([Fab-SWn-PE38] 2 ) antibody-toxins. The cytotoxicity of the dimer against the CRL1739 cell line was approximately 18.8-fold higher than that of the monomer on the ng/ml scale, which was approximately 37.6-fold higher on the pM scale. These results strongly indicate that divalency provides higher cytotoxicity for an antibody-toxin.
Studies on the Electrochemical Behavior of Thiazolidine and Its Applications Using a Flow–Through Chronoamperometric Sensor Based on a Gold Electrode

Directory of Open Access Journals (Sweden)

Lai-Hao Wang

2011-09-01

Full Text Available The electrochemical behaviors of thiazolidine (tetrahydrothiazole on gold and platinum electrodes were investigated in a Britton-Robinson buffer (pH 2.77–11.61, acetate buffer (pH 4.31, phosphate buffer solutions (pH 2.11 and 6.38 and methanol or acetonitrile containing various supporting electrolytes. Detection was based on a gold wire electrochemical signal obtained with a supporting electrolyte containing 20% methanol-1.0 mM of phosphate buffer (pH 6.87, potassium dihydrogen phosphate and dipotassium hydrogen phosphate as the mobile phase. Comparison with results obtained with a commercial amperometric detector shows good agreement. Using the chronoamperometric sensor with the current at a constant potential, and measurements with suitable experimental parameters, a linear concentration from 0.05 to 16 mg L−1 was found. The limit of quantification (LOQ of the method for thiazolidine was found to be 1 ng.
Potassium Chloride Versus Voltage Clamp Contractures in Ventricular Muscle

Science.gov (United States)

Morad, M.; Reeck, S.; Rao, M.

1981-01-01

In frog ventricle, developed tension was markedly larger in response to depolarization caused by a voltage clamp step than to depolarization induced by high concentrations of potassium chloride. Measurement of extracellular potassium activity at the surface and at the depth of muscle during the development of contractures showed that the diffusion of potassium is much slower than the spread of depolarization through the cross section of muscle. These two observations suggest that competition between the depolarizing and the negative inotropic effects of an increase in the extracellular potassium ion concentration may determine the time course and magnitude of contractile tension in heart muscle.

Gold Returns

OpenAIRE

Robert J. Barro; Sanjay P. Misra

2013-01-01

From 1836 to 2011, the average real rate of price change for gold in the United States is 1.1% per year and the standard deviation is 13.1%, implying a one-standard-deviation confidence band for the mean of (0.1%, 2.1%). The covariances of gold's real rate of price change with consumption and GDP growth rates are small and statistically insignificantly different from zero. These negligible covariances suggest that gold's expected real rate of return--which includes an unobserved dividend yiel...
Coal-oil gold agglomeration assisted flotation to recover gold from refractory ore

Science.gov (United States)

Otsuki, A.; Yue, C.

2017-07-01

This study aimed to investigate the applicability of coal-oil gold agglomeration (CGA) assisted flotation to recover gold from a refractory ore. The ore with the grade of 2-5 g/t was tested with the CGA-flotation process in six different size fractions from 38 to 300 urn using different collector types and dosages. In addition, the flotation without CGA was performed under the same condition for comparison. The results showed that the higher gold grade and recovery were achieved by applying the CGA-flotation, compared with the flotation without CGA. More than 20-60 times grade increase from the head grade was obtained with CGA-flotation. The elemental analysis of gold and sulphur explained their relationship with gold recovery. The results well indicated the applicability of CGA to upgrade the refractory gold ore.
Study the Possibility of measuring Heavy Metals Arising from Gold Mining Sample using 252Cf Neutron Source

International Nuclear Information System (INIS)

Soliman, N.F.

2012-01-01

Mining activities contribute immensely to trace element pollution .The present work studied the possibility of measuring heavy metals arising from gold mining areas Eastern Desert in Egypt using the isotopic 252 Cf neutron source. 38.5 g of the sample is irradiated in a neutron field of 252 Cf for 36.75 days and 0.3 mg of the sample is irradiated at the Pneumatic Irradiation Rabbit System (PIRS) built in the vertical thermal column of the ET-RR-2 reactor . The induced activities in the samples are measured using two high resolution f ray spectrometry systems (including two calibrated HPGe detectors). The kο standardization neutron activation analysis (kο-NAA) method was used to analyze the sample under investigation. Thermal to epithermal flux ratio fat the two irradiation positions are measured. The obtained results indicated that the values of the suspected heavy metals such as sodium, magnesium, potassium, manganese, arsenic, ruthenium and tantalum were higher than the background values, signifying accumulation of these heavy metals due to gold mining activities .The accuracy and precision of the method has been evaluated
ROLE OF POTASSIUM IN THE OXIDATIVE METABOLISM OF MICROCOCCUS SODONENSIS1

Science.gov (United States)

Perry, Jerome J.; Evans, James B.

1961-01-01

Perry, Jerome J. (The University of Chicago, Chicago, Ill.), and James B. Evans. Role of potassium in the oxidative metabolism of Micrococcus sodonensis. J. Bacteriol. 82:551–555. 1961.—An absolute potassium requirement has been established for the growth of Micrococcus sodonensis with lactate or pyruvate as substrate. Potassium at 0.67 × 10−2m concentration was necessary for maximal growth. Resting cell and cell-free preparations from cells grown on minimal levels of potassium were stimulated by potassium but, due to residual or bound cation, did not show an absolute requirement. Rubidium and cesium replaced potassium in these cells although cesium is much less effective. PMID:14485577
Gold and gold-copper nanoparticles in 2-propanol: A radiation chemical study

International Nuclear Information System (INIS)

Dey, G.R.

2011-01-01

The studies on the reduction of Au 3+ to gold nanoparticles in presence and absence of Cu 2+ under deoxygenated conditions in 2-propanol by radiolytic method have been carried out. On γ-radiolysis, preliminary yellow colored solution of Au 3+ changed to purple color owing to gold nanoparticles formation, which exhibits an absorption peak at around 540 nm. In the presence of Cu 2+ , absorption of gold-copper nanoparticles, which was also produced during γ-radiolysis, was red shifted in contrast to the system containing no Cu 2+ . Under DLS studies the sizes of gold nanoparticles in the absence and the presence of Cu 2+ were found to be larger (>400 nm). However, in presence of polyethylene glycol, a stabilizer the nanoparticle sizes became smaller, sizes measured for gold and gold-copper nanoparticles are 40 and 140 nm, respectively. Moreover, the change in UV-vis spectra in the Cu 2+ and Au 3+ mixed system highlights the formation of gold-copper nanoparticles in core-shell type arrangement. - Highlights: → Present radiation chemical study highlights high reactivity of Au ·2+ with Cu 2+ . → Absorption of gold-copper nanoparticles is blue shifted as compared to copper nanoparticles. → Change in UV-vis spectra with dose emphasizes core-shell type arrangement of Au-Cu nanoparticles.
Gold in plants

International Nuclear Information System (INIS)

Girling, C.A.; Peterson, P.J.

1980-01-01

Many plants have the ability to take up gold from the soil and to accumulate it in their tisssue. Advances have been made in understanding these processes to the point where their exploitation in the field of prospecting for gold appears practically feasible. Neutron activation analysis is used for the determination of the small quantities of gold in plants
Performance analysis of a potassium-steam two stage vapour cycle

International Nuclear Information System (INIS)

Mitachi, Kohshi; Saito, Takeshi

1983-01-01

It is an important subject to raise the thermal efficiency in thermal power plants. In present thermal power plants which use steam cycle, the plant thermal efficiency has already reached 41 to 42 %, steam temperature being 839 K, and steam pressure being 24.2 MPa. That is, the thermal efficiency in a steam cycle is facing a limit. In this study, analysis was made on the performance of metal vapour/steam two-stage Rankine cycle obtained by combining a metal vapour cycle with a present steam cycle. Three different combinations using high temperature potassium regenerative cycle and low temperature steam regenerative cycle, potassium regenerative cycle and steam reheat and regenerative cycle, and potassium bleed cycle and steam reheat and regenerative cycle were systematically analyzed for the overall thermal efficiency, the output ratio and the flow rate ratio, when the inlet temperature of a potassium turbine, the temperature of a potassium condenser, and others were varied. Though the overall thermal efficiency was improved by lowering the condensing temperature of potassium vapour, it is limited by the construction because the specific volume of potassium in low pressure section increases greatly. In the combinatipn of potassium vapour regenerative cycle with steam regenerative cycle, the overall thermal efficiency can be 58.5 %, and also 60.2 % if steam reheat and regenerative cycle is employed. If a cycle to heat steam with the bled vapor out of a potassium vapour cycle is adopted, the overall thermal efficiency of 63.3 % is expected. (Wakatsuki, Y.)
The Limitation Amount of Available Potassium for Wheat in a Loess Soil

Directory of Open Access Journals (Sweden)

M. Vafakhah

2014-04-01

Full Text Available The objective of this study was determining the most limiting plant growth factor in the wheat root zone dominated by illite in clay fraction and a high specific surface with ample ammonium acetate extractible potassium. A completely randomized block design with 4 replicates was used in Seyed Miran Research Farm (Gorgan during 2009-2010 growing season. Treatments were mineral fertilizers (to achieve different levels of yields, gypsum (1000 Kg/ha calcium, calcium chloride (1000 Kg ha-1 Ca, urea (93 Kg ha-1 N and potassium chloride (105 Kg ha-1 K combined, gypsum (1000 Kg ha-1 Ca and potassium chloride (105 Kg ha-1 K combined, calcium chloride (1000 Kg ha-1 Ca and potassium chloride (105 Kg ha-1 K combined and control. Wheat cultivar (N-80-19 was planted in experimental site at 2009/12/9. The results showed that potassium is the most limiting plant growth factor in the site of the experiment. Electric diffuse double layer is expected to be truncated with a high specific surface soil in this area minimizing the soil solution-diffuse double layer interface for rapid potassium diffusion. The highest yield grain and straw with urea and potassium chloride showed a greater effect on plant and soil potassium concentrations. A greater potassium diffusion rate may be achieved as a result of greater concentration gradients between the exchange sites and soil solution by potassium fertilization and more potassium excess. Ammonium from urea diminished potassium fixation with illite and increased potassium root uptake.
Evaluating status change of soil potassium from path model.

Directory of Open Access Journals (Sweden)

Wenming He

Full Text Available The purpose of this study is to determine critical environmental parameters of soil K availability and to quantify those contributors by using a proposed path model. In this study, plot experiments were designed into different treatments, and soil samples were collected and further analyzed in laboratory to investigate soil properties influence on soil potassium forms (water soluble K, exchangeable K, non-exchangeable K. Furthermore, path analysis based on proposed path model was carried out to evaluate the relationship between potassium forms and soil properties. Research findings were achieved as followings. Firstly, key direct factors were soil S, ratio of sodium-potassium (Na/K, the chemical index of alteration (CIA, Soil Organic Matter in soil solution (SOM, Na and total nitrogen in soil solution (TN, and key indirect factors were Carbonate (CO3, Mg, pH, Na, S, and SOM. Secondly, path model can effectively determine direction and quantities of potassium status changes between Exchangeable potassium (eK, Non-exchangeable potassium (neK and water-soluble potassium (wsK under influences of specific environmental parameters. In reversible equilibrium state of [Formula: see text], K balance state was inclined to be moved into β and χ directions in treatments of potassium shortage. However in reversible equilibrium of [Formula: see text], K balance state was inclined to be moved into θ and λ directions in treatments of water shortage. Results showed that the proposed path model was able to quantitatively disclose moving direction of K status and quantify its equilibrium threshold. It provided a theoretical and practical basis for scientific and effective fertilization in agricultural plants growth.
21 CFR 250.108 - Potassium permanganate preparations as prescription drugs.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Potassium permanganate preparations as... or Prescription Status of Specific Drugs § 250.108 Potassium permanganate preparations as... women resulting from the misuse of potassium permanganate in an effort to induce abortion. Reports from...
Moessbauer study of the chemical state of gold in gold ores

International Nuclear Information System (INIS)

Wagner, F.E.; Marion, P.H.; Regnard, J.-R.

1986-01-01

Information on the chemical state of gold in gold ores has been obtained by 197 Au Moessbauer spectroscopy in cases where the state of this element cannot be determined by such standard methods as optical or electron microscopy. Ore concentrates consisting mainly of pyrite or arsenopyrite and roasted ore and matte samples were studied. The results yielded directly the respective amounts of metallic and chemically bound gold. Unless the gold is metallic, its chemical state in the ores turns out to be different from that in the minerals studied so far as reference materials. The chemical processes taking place during various treatments of the ores, such as roasting or leaching, can also be followed by Moessbauer spectroscopy. It is hoped that Moessbauer spectroscopy will eventually facilitate the development of more efficient methods of gold extraction
Highly nonlinear sub-micron silicon nitride trench waveguide coated with gold nanoparticles

Science.gov (United States)

Huang, Yuewang; Zhao, Qiancheng; Sharac, Nicholas; Ragan, Regina; Boyraz, Ozdal

2015-05-01

We demonstrate the fabrication of a highly nonlinear sub-micron silicon nitride trench waveguide coated with gold nanoparticles for plasmonic enhancement. The average enhancement effect is evaluated by measuring the spectral broadening effect caused by self-phase-modulation. The nonlinear refractive index n2 was measured to be 7.0917×10-19 m2/W for a waveguide whose Wopen is 5 μm. Several waveguides at different locations on one wafer were measured in order to take the randomness of the nanoparticle distribution into consideration. The largest enhancement is measured to be as high as 10 times. Fabrication of this waveguide started with a MEMS grade photomask. By using conventional optical lithography, the wide linewidth was transferred to a wafer. Then the wafer was etched anisotropically by potassium hydroxide (KOH) to engrave trapezoidal trenches with an angle of 54.7º. Side wall roughness was mitigated by KOH etching and thermal oxidation that was used to generate a buffer layer for silicon nitride waveguide. The guiding material silicon nitride was then deposited by low pressure chemical vapor deposition. The waveguide was then patterned with a chemical template, with 20 nm gold particles being chemically attached to the functionalized poly(methyl methacrylate) domains. Since the particles attached only to the PMMA domains, they were confined to localized regions, therefore forcing the nanoparticles into clusters of various numbers and geometries. Experiments reveal that the waveguide has negligible nonlinear absorption loss, and its nonlinear refractive index can be greatly enhanced by gold nano clusters. The silicon nitride trench waveguide has large nonlinear refractive index, rendering itself promising for nonlinear applications.
Silver, gold, and alloyed silver-gold nanoparticles: characterization and comparative cell-biologic action

Science.gov (United States)

Mahl, Dirk; Diendorf, Jörg; Ristig, Simon; Greulich, Christina; Li, Zi-An; Farle, Michael; Köller, Manfred; Epple, Matthias

2012-10-01

Silver, gold, and silver-gold-alloy nanoparticles were prepared by citrate reduction modified by the addition of tannin during the synthesis, leading to a reduction in particle size by a factor of three. Nanoparticles can be prepared by this easy water-based synthesis and subsequently functionalized by the addition of either tris(3-sulfonatophenyl)phosphine or poly( N-vinylpyrrolidone). The resulting nanoparticles of silver (diameter 15-25 nm), gold (5-6 nm), and silver-gold (50:50; 10-12 nm) were easily dispersable in water and also in cell culture media (RPMI + 10 % fetal calf serum), as shown by nanoparticle tracking analysis and differential centrifugal sedimentation. High-resolution transmission electron microscopy showed a polycrystalline nature of all nanoparticles. EDX on single silver-gold nanoparticles indicated that the concentration of gold is higher inside a nanoparticle. The biologic action of the nanoparticles toward human mesenchymal stem cells (hMSC) was different: Silver nanoparticles showed a significant concentration-dependent influence on the viability of hMSC. Gold nanoparticles showed only a small effect on the viability of hMSC after 7 days. Surprisingly, silver-gold nanoparticles had no significant influence on the viability of hMSC despite the silver content. Silver nanoparticles and silver-gold nanoparticles in the concentration range of 5-20 μg mL-1 induced the activation of hMSC as indicated by the release of IL-8. In contrast, gold nanoparticles led to a reduction of the release of IL-6 and IL-8.
Potassium isotope abundances in Australasian tektites and microtektites.

Science.gov (United States)

Herzog, G. F.; O'D. Alexander, C. M.; Berger, E. L.; Delaney, J. S.; Glass, B. P.

2008-10-01

We report electron microprobe determinations of the elemental compositions of 11 Australasian layered tektites and 28 Australasian microtektites; and ion microprobe determinations of the 41K/39K ratios of all 11 tektites and 13 of the microtektites. The elemental compositions agree well with literature values, although the average potassium concentrations measured here for microtektites, 1.1 1.6 wt%, are lower than published average values, 1.9 2.9 wt%. The potassium isotope abundances of the Australasian layered tektites vary little. The average value of δ41K, 0.02 ± 0.12‰ (1σ mean), is indistinguishable from the terrestrial value (= 0 by definition) as represented by our standard, thereby confirming four earlier tektite analyses of Humayun and Koeberl (2004). In agreement with those authors, we conclude that evaporation has significantly altered neither the isotopic nor the elemental composition of Australasian layered tektites for elements less volatile than potassium. Although the average 41K/39K ratio of the microtektites, 1.1 ± 1.7‰ (1σ mean), is also statistically indistinguishable from the value for the standard, the individual ratios vary over a very large range, from -10.6 ± 1.4‰ to +13.8 ± 1.5‰ and at least three of them are significantly different from zero. We interpret these larger variations in terms of the evaporation of isotopically light potassium; condensation of potassium in the vapor plume; partial or complete stirring and quenching of the melts; and the possible uptake of potassium from seawater. That the average 41K/39K ratio of the microtektites equals the terrestrial value suggests that the microtektite-forming system was compositionally closed with respect to potassium and less volatile elements. The possibility remains open that 41K/39K ratios of microtektites vary systematically with location in the strewn field.
Potassium doped MWCNTs for hydrogen storage enhancement

International Nuclear Information System (INIS)

Adabi Qomi, S.; Gashtasebi, M.; Khoshnevisan, B.

2012-01-01

Here we have used potassium doped MWCNTs for enhancement of hydrogen storage process. XRD and SEM images have confirmed the doping of potassium. For studying the storage process a hydrogenic battery set up has been used. In the battery the working electrode has been made of the silver foam deposited by the doped MWCNTs electrophoretically.
Electron magnetic resonance study of monovalent Na doping in Pr0.6Sr0.4−xNaxMnO3 manganites

International Nuclear Information System (INIS)

Thaljaoui, Rachid; Boujelben, Wahiba; Pękała, Marek; Szydłowska, Jadwiga; Cheikhrouhou, Abdelwaheb

2012-01-01

Highlights: ► New monovalent doped manganites Pr 0.6 Sr 0.4−x Na x MnO 3 (x = 0, 0.05). ► Comparison of electron magnetic resonance spectra in ferro- and paramagnetic phases. ► Double exchange interactions weakened by Na doping as indicated by activation energy. ► Magnetic susceptibility derived from resonance intensity obeys Curie–Weiss law. - Abstract: Effect of monovalent Na doping on the magnetic properties is studied in Pr 0.6 Sr 0.4−x Na x MnO 3 system (x = 0, 0.05) using X-band electron magnetic resonance and magnetization measurements. Temperature variation of magnetic resonance spectra of doped and undoped manganites is analyzed for paramagnetic and ferromagnetic states and compared to similar systems. In paramagnetic phase the magnetic susceptibility proportional to resonance signal intensity is found to obey the Curie–Weiss law. The effective magnetic moment becomes smaller in doped manganite. The paramagnetic Curie temperature derived from signal intensity equals to 312 and 306 K for the undoped and doped manganites, respectively, and is close to values obtained from magnetization variation in paramagnetic phase. The activation energy determined using the adiabatic small polaron hopping model is higher for the undoped than the doped manganite, which proves that the Na doping slightly reduces the Mn 3+ /Mn 4+ double exchange interactions.
Test Requirements and Conceptual Design for a Potassium Test Loop to Support an Advanced Potassium Rankine Cycle Power Conversion Systems

Energy Technology Data Exchange (ETDEWEB)

Yoder, JR.G.L.

2006-03-08

Parameters for continuing the design and specification of an experimental potassium test loop are identified in this report. Design and construction of a potassium test loop is part of the Phase II effort of the project ''Technology Development Program for an Advanced Potassium Rankine Power Conversion System''. This program is supported by the National Aeronautics and Space Administration. Design features for the potassium test loop and its instrumentation system, specific test articles, and engineered barriers for ensuring worker safety and protection of the environment are described along with safety and environmental protection requirements to be used during the design process. Information presented in the first portion of this report formed the basis to initiate the design phase of the program; however, the report is a living document that can be changed as necessary during the design process, reflecting modifications as additional design details are developed. Some portions of the report have parameters identified as ''to be determined'' (TBD), reflecting the early stage of the overall process. In cases where specific design values are presently unknown, the report attempts to document the quantities that remain to be defined in order to complete the design of the potassium test loop and supporting equipment.
Gold deposit styles and placer gold characterisation in northern and east-central Madagascar

Science.gov (United States)

Pitfield, Peter E. J; Styles, Michael T.; Taylor, Cliff D.; Key, Roger M.; Bauer,; Ralison, A

2009-01-01

Microchemical characterisation of bedrock and placer gold grains from six gold districts within the Archaean domains and intervening Neoproterozoic Anaboriana-Manampotsy belt of northern and east-central Madagascar show few opaque inclusions (e.g pyrrhotite, Bi tellurides) but wide range of Ag contents (40wt%). Some districts exhibit multiple source populations of grains. The ‘greenstone belt’ terranes have an orogenic gold signature locally with an intrusion-related to epithermal overprint. Proterozoic metasediments with felsic to ultramafic bodies yield dominantly intrusion-related gold. A high proportion of secondary gold (<0.5wt% Ag) is related to recycling of paleoplacers and erosion of post-Gondwana planation surfaces and indicates that some mesothermal gold systems were already partially to wholly removed by erosion by the PermoTriassic.
Analysis of gold and silver concentration on gold mining tailings by neutron activation analysis

International Nuclear Information System (INIS)

Sadikov, I.I.; Salimov, M.I.; Sadykova, Z.O.

2014-01-01

Full text: Instrumental neutron-activation analysis without radiochemical separation is one of most applicable and often used methods to analyze the concentration of gold, silver and other rare and noble metals in gold ores. This method is not suitable for analyzing low concentration of gold and silver in gold mining tailings due to rather high concentration of some elements. Samples are dissolved by boiling in a mixture of concentrated hydrochloric and nitric acids to extract gold and silver into the solution. Chemical yield of gold and silver after dissolution of the sample and further chromatographic separation is between 92 and 95 percent respectively
Gold nanoparticle formation in diamond-like carbon using two different methods: Gold ion implantation and co-deposition of gold and carbon

International Nuclear Information System (INIS)

Salvadori, M. C.; Teixeira, F. S.; Araújo, W. W. R.; Sgubin, L. G.; Cattani, M.; Spirin, R. E.; Brown, I. G.

2012-01-01

We describe work in which gold nanoparticles were formed in diamond-like carbon (DLC), thereby generating a Au-DLC nanocomposite. A high-quality, hydrogen-free DLC thin film was formed by filtered vacuum arc plasma deposition, into which gold nanoparticles were introduced using two different methods. The first method was gold ion implantation into the DLC film at a number of decreasing ion energies, distributing the gold over a controllable depth range within the DLC. The second method was co-deposition of gold and carbon, using two separate vacuum arc plasma guns with suitably interleaved repetitive pulsing. Transmission electron microscope images show that the size of the gold nanoparticles obtained by ion implantation is 3-5 nm. For the Au-DLC composite obtained by co-deposition, there were two different nanoparticle sizes, most about 2 nm with some 6-7 nm. Raman spectroscopy indicates that the implanted sample contains a smaller fraction of sp 3 bonding for the DLC, demonstrating that some sp 3 bonds are destroyed by the gold implantation.

Thermogravimetric studies of high temperature reactions between potassium salts and chromium

International Nuclear Information System (INIS)

Lehmusto, J.; Lindberg, D.; Yrjas, P.; Skrifvars, B.-J.; Hupa, M.

2012-01-01

Highlights: ► K 2 CO 3 reacted with Cr 2 O 3 forming K 2 CrO 4 . ► Presence of chlorine did not alone explain the initiation of accelerated oxidation. ► More light was shed to the role of chromates in accelerated oxidation. ► Accelerated oxidation of chromia protected steels occurs in two consecutive stages. ► Both potassium and chloride are required, so that both stages of reaction occur. - Abstract: This study compares the high temperature reactions of potassium chloride (KCl) and potassium carbonate (K 2 CO 3 ), two salts found in fly ashes formed in biomass combustion, with both pure metallic chromium (Cr) and chromium oxide (Cr 2 O 3 ). The reactions were investigated with thermogravimetric measurements and the results discussed based on thermodynamic calculations. In simple terms: potassium chloride reacted with chromium forming potassium chromate (K 2 CrO 4 ) and chromium oxide. Potassium chloride did not react with chromium oxide. Potassium carbonate reacted with chromium oxide, but not with chromium. The presence of potassium is sufficient to initiate accelerated oxidation, but chloride is needed to sustain it.
Electrical properties of the potassium polytitanate compacts

International Nuclear Information System (INIS)

Goffman, V.G.; Gorokhovsky, A.V.; Kompan, M.M.; Tretyachenko, E.V.; Telegina, O.S.; Kovnev, A.V.; Fedorov, F.S.

2014-01-01

Highlights: • Quasi-static permittivity of potassium polytitanates compacts achieves 10 4 –10 5 . • Observed Maxwell–Wagner polarization attributes to layered structure of polytitanates. • The conductivity varies from 5 × 10 −2 to 10 −6 –10 −7 Sm/m in a wide range of temperatures. - Abstract: Titanates of alkali metals are widely applied materials as they are relatively low in cost and might be easily synthesized. They are utilized as adsorbents, catalysts, solid state electrolytes, superconductors. Here we report our results on electrical properties of the compacted amorphous potassium polytitanates powders. The electrical properties of the compacts were studied by means of complex impedance spectroscopy in a wide range of frequencies at different temperatures using two-electrode configuration. The frequency dependences of conductivity for the investigated potassium polytitanates compacts varies in the range from 5 × 10 −2 Sm/m (high frequencies, ion conductivity) up to 10 −6 –10 −7 Sm/m (low frequencies, electron conductivity) for a wide range of temperatures (19–150 °C). According to the results, at low frequencies quasi-static permittivity of the stabilized PPT compacts achieves high values of 10 4 –10 5 . This might be explained by Maxwell–Wagner polarization attributed to the layered structure of the potassium polytitanates particles containing potassium and hydronium ions together with crystallization water in the interlayer and is very promising for solid state electrolyte applications for moderate temperatures
Silver, gold, and alloyed silver-gold nanoparticles: characterization and comparative cell-biologic action

Energy Technology Data Exchange (ETDEWEB)

Mahl, Dirk; Diendorf, Joerg; Ristig, Simon [University of Duisburg-Essen, Department of Inorganic Chemistry, Center for Nanointegration Duisburg-Essen (CeNIDE) (Germany); Greulich, Christina [Ruhr-University of Bochum, Bergmannsheil University Hospital/Surgical Research (Germany); Li Zian; Farle, Michael [University of Duisburg-Essen, Faculty of Physics, Center for Nanointegration Duisburg-Essen (CeNIDE) (Germany); Koeller, Manfred [Ruhr-University of Bochum, Bergmannsheil University Hospital/Surgical Research (Germany); Epple, Matthias, E-mail: matthias.epple@uni-due.de [University of Duisburg-Essen, Department of Inorganic Chemistry, Center for Nanointegration Duisburg-Essen (CeNIDE) (Germany)

2012-10-15

Silver, gold, and silver-gold-alloy nanoparticles were prepared by citrate reduction modified by the addition of tannin during the synthesis, leading to a reduction in particle size by a factor of three. Nanoparticles can be prepared by this easy water-based synthesis and subsequently functionalized by the addition of either tris(3-sulfonatophenyl)phosphine or poly(N-vinylpyrrolidone). The resulting nanoparticles of silver (diameter 15-25 nm), gold (5-6 nm), and silver-gold (50:50; 10-12 nm) were easily dispersable in water and also in cell culture media (RPMI + 10 % fetal calf serum), as shown by nanoparticle tracking analysis and differential centrifugal sedimentation. High-resolution transmission electron microscopy showed a polycrystalline nature of all nanoparticles. EDX on single silver-gold nanoparticles indicated that the concentration of gold is higher inside a nanoparticle. The biologic action of the nanoparticles toward human mesenchymal stem cells (hMSC) was different: Silver nanoparticles showed a significant concentration-dependent influence on the viability of hMSC. Gold nanoparticles showed only a small effect on the viability of hMSC after 7 days. Surprisingly, silver-gold nanoparticles had no significant influence on the viability of hMSC despite the silver content. Silver nanoparticles and silver-gold nanoparticles in the concentration range of 5-20 {mu}g mL{sup -1} induced the activation of hMSC as indicated by the release of IL-8. In contrast, gold nanoparticles led to a reduction of the release of IL-6 and IL-8.
Silver, gold, and alloyed silver–gold nanoparticles: characterization and comparative cell-biologic action

International Nuclear Information System (INIS)

Mahl, Dirk; Diendorf, Jörg; Ristig, Simon; Greulich, Christina; Li Zian; Farle, Michael; Köller, Manfred; Epple, Matthias

2012-01-01

Silver, gold, and silver–gold-alloy nanoparticles were prepared by citrate reduction modified by the addition of tannin during the synthesis, leading to a reduction in particle size by a factor of three. Nanoparticles can be prepared by this easy water-based synthesis and subsequently functionalized by the addition of either tris(3-sulfonatophenyl)phosphine or poly(N-vinylpyrrolidone). The resulting nanoparticles of silver (diameter 15–25 nm), gold (5–6 nm), and silver–gold (50:50; 10–12 nm) were easily dispersable in water and also in cell culture media (RPMI + 10 % fetal calf serum), as shown by nanoparticle tracking analysis and differential centrifugal sedimentation. High-resolution transmission electron microscopy showed a polycrystalline nature of all nanoparticles. EDX on single silver–gold nanoparticles indicated that the concentration of gold is higher inside a nanoparticle. The biologic action of the nanoparticles toward human mesenchymal stem cells (hMSC) was different: Silver nanoparticles showed a significant concentration-dependent influence on the viability of hMSC. Gold nanoparticles showed only a small effect on the viability of hMSC after 7 days. Surprisingly, silver–gold nanoparticles had no significant influence on the viability of hMSC despite the silver content. Silver nanoparticles and silver–gold nanoparticles in the concentration range of 5–20 μg mL −1 induced the activation of hMSC as indicated by the release of IL-8. In contrast, gold nanoparticles led to a reduction of the release of IL-6 and IL-8.
(Vapour + liquid) equilibria, volumetric and compressibility behaviour of binary and ternary aqueous solutions of 1-hexyl-3-methylimidazolium chloride, methyl potassium malonate, and ethyl potassium malonate

International Nuclear Information System (INIS)

Sadeghi, Rahmat; Mahdavi, Adibeh

2012-01-01

Highlights: ► VLE and volumetry of binary and ternary [C 6 mim][Cl], MPM and EPM aqueous solutions. ► Constant a w lines show small negative deviation from the linear isopiestic relation. ► Solute–water interactions follow the order: EPM > MPM > [C 6 mim][Cl]. ► MPM and EPM have a very weak salting-out effect on [C 6 mim][Cl] aqueous solutions. - Abstract: (Vapour + liquid) equilibrium data (water activity, vapour pressure, osmotic coefficient, and activity coefficient) of binary aqueous solutions of 1-hexyl-3-methylimidazolium chloride ([C 6 mim][Cl]), methyl potassium malonate, and ethyl potassium malonate and ternary {[C 6 mim][Cl] + methyl potassium malonate} and {[C 6 mim][Cl] + ethyl potassium malonate} aqueous solutions were obtained through the isopiestic method at T = 298.15 K. These results reveal that the ionic liquid behaves as surfactant-like and aggregates in aqueous solutions at molality about 0.4 mol · kg −1 . The constant water activity lines of all the ternary systems investigated show small negative deviations from the linear isopiestic relation (Zdanovskii–Stokes–Robinson rule) derived using the semi-ideal hydration model. The density and speed of sound measurements were carried out on solutions of methyl potassium malonate and ethyl potassium malonate in water and of [C 6 mim][Cl] in aqueous solutions of 0.25 mol · kg −1 methyl potassium malonate and ethyl potassium malonate at T = (288.15 to 308.15) K at atmospheric pressure. From the experimental density and speed of sound data, the values of the apparent molar volume, apparent molar isentropic compressibility and excess molar volume were evaluated and from which the infinite dilution apparent molar volume and infinite dilution apparent molar isentropic compressibility were calculated at each temperature. Although, there are no clear differences between the values of the apparent molar volume of [C 6 mim][Cl] in pure water and in methyl potassium malonate or ethyl
For the love of gold

International Nuclear Information System (INIS)

Young, J.E.

1993-01-01

Gold is found in minute quantities and gold mining generates enormous amounts of waste materials and long history of environmental destruction: mercury in tailing, eroded land, and acid mine drainage are legacies of the past. The problem has become worse in recent years in North America, Australia, the Amazon basin, Philippines. This paper describes the economics of gold and the changes in the world economy which has precipitated the new gold rushes. Current technology uses a cyanide solution for leaching small amounts of gold from tons of waste, and mercury remains a toxic waste of gold mining. Both short and long term results of gold mining, on the environment and on indiginous populations are described
Tunable release of clavam from clavam stabilized gold nanoparticles — Design, characterization and antimicrobial study

Energy Technology Data Exchange (ETDEWEB)

Manju, V. [Electrodics and Electrocatalysis Division, CSIR-Central Electrochemical Research Institute, Karaikudi, Tamilnadu 630006 (India); Dhandapani, P. [Corrosion Materials and Protection Division, CSIR-Central Electrochemical Research Institute, Karaikudi, Tamilnadu, 630006 (India); Gurusamy Neelavannan, M. [Characterization and Measurement lab, CSIR-Central Electrochemical Research Institute, Karaikudi, Tamilnadu 630006 (India); Maruthamuthu, S. [Corrosion Materials and Protection Division, CSIR-Central Electrochemical Research Institute, Karaikudi, Tamilnadu, 630006 (India); Berchmans, S. [Electrodics and Electrocatalysis Division, CSIR-Central Electrochemical Research Institute, Karaikudi, Tamilnadu 630006 (India); Palaniappan, A., E-mail: palani112@gmail.com [Electrodics and Electrocatalysis Division, CSIR-Central Electrochemical Research Institute, Karaikudi, Tamilnadu 630006 (India)

2015-04-01

A facile one-step approach is developed to synthesize highly stable (up to 6 months) gold nanoparticles (GNPs) using Clavam, pharmaceutical form of amoxicillin which contains a mixture of amoxicillin and potassium salt of clavulanic acid, at room temperature (25–30 °C). The clavam stabilized GNPs are characterized using various techniques including UV–Visible, FT-IR spectrophotometry and transmission electron microscopy (TEM). Tunable release of clavam from clavam stabilized GNPs is demonstrated using intracellular concentrations of glutathione (GSH). The process is monitored using an UV–Vis spectroscopy and the amount of clavam released in terms of amoxicillin concentration is quantitatively estimated using reverse phase high performance liquid chromatographic (RP-HPLC) technique. In vitro study reveals that the clavam released from GNPs' surface was found to show a significant enhancement in antibacterial activity against Escherichia coli and the cause of enhancement is addressed. - Graphical abstract: Stable and nearly monodisperse gold nanoparticles (GNPs) are prepared at room temperature (~ 25–30 °C) using clavam; commercial form of amoxicillin antibiotic. Tunable release of clavam from clavam stabilized GNPs is demonstrated by the addition of varying concentrations of glutathione. Interactions between clavam and gold core are investigated in detail. The mechanism of enhanced antimicrobial activity of clavam released from clavam stabilized GNPs is probed. - Highlights: • Gold nanoparticles (GNPs) are prepared without reducing agent using antibiotic clavam{sup TR}. • Our work shed lights on the nature of interaction between the clavam and GNPs. • Sustained release of clavam from clavam stabilized GNPs is demonstrated using glutathione. • Antimicrobial activity of the released clavam is confirmed using various techniques. • Our study suggests that the clavam released from GNPs shows better inhibition of E. coli.
Frontiers in Gold Chemistry

OpenAIRE

Ahmed A. Mohamed

2015-01-01

Basic chemistry of gold tells us that it can bond to sulfur, phosphorous, nitrogen, and oxygen donor ligands. The Frontiers in Gold Chemistry Special Issue covers gold complexes bonded to the different donors and their fascinating applications. This issue covers both basic chemistry studies of gold complexes and their contemporary applications in medicine, materials chemistry, and optical sensors. There is a strong belief that aurophilicity plays a major role in the unending applications of g...
Variable Potassium Concentrations: Which Is Right and Which Is Wrong?

Science.gov (United States)

Theparee, Talent; Benirschke, Robert C; Lee, Hong-Kee

2017-05-01

Reverse pseudohyperkalemia is a term used to describe in vitro, falsely elevated potassium concentrations in plasma specimens that occur in association with extreme leukocytosis and are commonly associated with hematologic malignant neoplasms. Tumor lysis syndrome is an in vivo lysis of tumor cells that leads to elevated levels of potassium, uric acid, phosphate, and lactate dehydrogenase, as well as decreased calcium concentrations. Herein, we report a case of a 66-year-old Caucasian man with stage IV mantle-cell lymphoma who has elevated levels of potassium, uric acid, and phosphorus, as well as a white blood cell (WBC) count greater than 100,000 cells per mm3. The patient initially was diagnosed as having tumor lysis syndrome. His subsequent potassium concentrations in whole blood remained elevated even after hemodialysis; however, his serum potassium concentrations were decreased. The patient then was diagnosed accurately as having reverse pseudohyperkalemia, and accurate potassium measurements were obtained via serum specimens. © American Society for Clinical Pathology, 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Effect of potassium ferrate on disintegration of waste activated sludge (WAS).

Science.gov (United States)

Ye, Fenxia; Ji, Haizhuang; Ye, Yangfang

2012-06-15

The activated sludge process of wastewater treatment results in the generation of a considerable amount of excess activated sludge. Increased attention has been given to minimization of waste activated sludge recently. This paper investigated the effect of potassium ferrate oxidation pretreatment on the disintegration of the waste activated sludge at various dosages of potassium ferrate. The results show that potassium ferrate pretreatment disintegrated the sludge particle, resulting in the reduction of total solid content by 31%. The solubility (SCOD/TCOD) of the sludge increased with the increase of potassium ferrate dosage. Under 0.81 g/g SS dosage of potassium ferrate, SCOD/TCOD reached 0.32. Total nitrogen (TN) and total phosphorous (TP) concentrations in the solution all increased significantly after potassium ferrate pretreatment. The sludge particles reduced from 116 to 87 μm. The settleability of the sludge (SVI) was enhanced by 17%, which was due to the re-flocculation by the by-product, Fe(III), during potassium ferrate oxidation and the decrease of the viscosity. From the result of the present investigations, it can be concluded that potassium ferrate oxidation is a feasible method for disintegration of excess activated sludge. Copyright © 2012 Elsevier B.V. All rights reserved.
Cosolutes effects on aqueous two-phase systems equilibrium formation studied by physical approaches.

Science.gov (United States)

Bertoluzzo, M Guadalupe; Rigatuso, Rubén; Farruggia, Beatriz; Nerli, Bibiana; Picó, Guillermo

2007-10-01

The effect of urea and sodium salts of monovalent halides on the aqueous polyethyleneglycol solution and binodal diagrams of polyethyleneglycol-potassium phosphate (polyethyleneglycol of molecular mass 1500, 4000, 6000 and 8000) were studied using different physical approaches. The effect of these solutes on the binodal diagram for polyethyleneglycol-potassium phosphate was also investigated. The cosolutes affected in a significant manner the water structured around the ethylene chain of polyethyleneglycol inducing a lost of this. The equilibrium curves for the aqueous two-phase systems were fitting very well by a sigmoidal function with two parameters, which are closely related with the cosolute structure making or breaking capacity on the water ordered.
Potassium-Based Dual Ion Battery with Dual-Graphite Electrode.

Science.gov (United States)

Fan, Ling; Liu, Qian; Chen, Suhua; Lin, Kairui; Xu, Zhi; Lu, Bingan

2017-08-01

A potassium ion battery has potential applications for large scale electric energy storage systems due to the abundance and low cost of potassium resources. Dual graphite batteries, with graphite as both anode and cathode, eliminate the use of transition metal compounds and greatly lower the overall cost. Herein, combining the merits of the potassium ion battery and dual graphite battery, a potassium-based dual ion battery with dual-graphite electrode is developed. It delivers a reversible capacity of 62 mA h g -1 and medium discharge voltage of ≈3.96 V. The intercalation/deintercalation mechanism of K + and PF 6 - into/from graphite is proposed and discussed in detail, with various characterizations to support. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Solid contact potassium selective electrodes for biomedical applications – a review

NARCIS (Netherlands)

van de Velde, Lennart; d'Angremont, E.; Olthuis, Wouter

2016-01-01

Ion-selective electrodes (ISE) are used in several biomedical applications, including laboratory sensing of potassium concentration in blood and urine samples. For on-site determination of potassium concentration and usage in other applications such as determination of extracellular potassium
Potassium Permanganate Poisoning: A Nonfatal Outcome

Directory of Open Access Journals (Sweden)

Suzan M. Eteiwi

2015-07-01

Full Text Available Acute poisoning by potassium permanganate is a rare condition with high morbidity and mortality. Diagnosis of the condition relies on a history of exposure or ingestion and a high degree of clinical suspicion. Oxygen desaturation and the presence of methemoglobin are also helpful indicators. Since no specific antidote is available, treatment is mainly supportive. Few cases have been reported in the literature following potassium permanganate ingestion, whether intentional or accidental, and most of the patients in these cases had unfavorable outcomes, which was not the case in our patient. Our patient, a 73-year-old male, purchased potassium permanganate over the counter mistaking it for magnesium salt, which he frequently used as a laxative. Several hours after he ingested it, he was admitted to the endocrine department at King Hussein Medical Center, Jordan, with acute rapidly evolving shortness of breath. During hospitalization, his liver function tests deteriorated. Since he was diagnosed early and managed promptly he had a favorable outcome.
Possible potassium chlorate nephrotoxicity associated with chronic matchstick ingestion*

OpenAIRE

Thurlow, John S.; Little, Dustin J.; Baker, Thomas P.; Yuan, Christina M.

2013-01-01

We present a case of a 48-year-old active duty male soldier with a history of chronic exposure to potassium chlorate, later diagnosed with chronic interstitial nephritis. He reported regular matchstick consumption to prevent chigger (Trombicula autumnalis) bites, amounting to ?5.8 g of potassium chlorate over 3 years. Potassium chlorate can cause anuric renal failure within days of a toxic dose. Its slow excretion and mechanism of action suggest that renal toxicity may result from lower-dose ...
Potassium ferrate treatment of RFETS' contaminated groundwater

International Nuclear Information System (INIS)

1995-01-01

The potassium ferrate treatment study of Rocky Flats Environmental Technology Site (RFETS) groundwater was performed under the Sitewide Treatability Studies Program (STSP). This study was undertaken to determine the effectiveness of potassium ferrate in a water treatment system to remove the contaminants of concern (COCS) from groundwater at the RFETS. Potassium ferrate is a simple salt where the iron is in the plus six valence state. It is the iron at the plus six valence state (Fe +6 ) that makes it an unique water treatment chemical, especially in waters where the pH is greater than seven. In basic solutions where the solubility of the oxides/hydroxides of many of the COCs is low, solids are formed as the pH is raised. By using ferrate these solids are agglomerated so they can be effectively removed by sedimentation in conventional water treatment equipment. The objective of this study was to determine the quality of water after treatment with potassium ferrate and to determine if the Colorado Water Quality Control Commission (CWQCC) discharge limits for the COCs listed in Table 1.0-1 could be met. Radionuclides in the groundwater were of special concern
75 FR 63856 - Potassium Permanganate From China Determination

Science.gov (United States)

2010-10-18

... Permanganate From China Determination On the basis of the record \\1\\ developed in the subject five-year review... potassium permanganate from China would be likely to lead to continuation or recurrence of material injury... Commission are contained in USITC Publication 4183 (September 2010), entitled Potassium Permanganate from...
Determination of potassium in several plants and study of potassium transfer to different beverages, including tequila, by measurement of 40K

International Nuclear Information System (INIS)

Navarrete, J.M.; Muller, G.; Cabrera, L.; Martinez, T.

2006-01-01

Measurement of 40 K was used for determination of potassium concentrations in leaves of agave and maguey cactus leaves, and coffee beans of various origins. The procedure was also used to study potassium transfer to tequila (alcoholic drink made of agave cactus), and the cactus and coffee infusions using 40 K as a natural radioactive tracer. Counting of 40 K in Marinelli containers with the aid of a low background NaI(Tl) scintillation detection system for 12-24 hours was employed. The method appeared to be simple and suitable for determination of potassium concentrations in large samples, which eliminates homogeneity problems. (author)
Direct formation of gold nanorods on surfaces using polymer-immobilised gold seeds

Directory of Open Access Journals (Sweden)

Majid K. Abyaneh

2016-06-01

Full Text Available Herein, we present the formation of gold nanorods (GNRs on novel gold–poly(methyl methacrylate (Au–PMMA nanocomposite substrates with unprecedented growth control through the polymer molecular weight (Mw and gold-salt-to-polymer weight ratio. For the first time, GNRs have been produced by seed-mediated direct growth on surfaces that were pre-coated with polymer-immobilised gold seeds. A Au–PMMA nanocomposite formed by UV photoreduction has been used as the gold seed. The influence of polymer Mw and gold concentration on the formation of GNRs has been investigated and discussed. The polymer nanocomposite formed with a lower Mw PMMA and 20 wt % gold salt provides a suitable medium for growing well-dispersed GNRs. In this sample, the average dimension of produced GNRs is 200 nm in length with aspect ratios up to 10 and a distribution of GNRs to nanoparticles of nearly 22%. Suitable characterization techniques such as AFM and SEM have been used to support concept of the proposed growth method.
Electrical properties of the potassium polytitanate compacts

Energy Technology Data Exchange (ETDEWEB)

Goffman, V.G.; Gorokhovsky, A.V. [NanoTechProm Ltd., Saratov (Russian Federation); Saratov State Technical University, Saratov (Russian Federation); Kompan, M.M. [Physico-Technical Institute of the Russian Academy of Science, St. Petersburg (Russian Federation); Tretyachenko, E.V.; Telegina, O.S.; Kovnev, A.V. [NanoTechProm Ltd., Saratov (Russian Federation); Saratov State Technical University, Saratov (Russian Federation); Fedorov, F.S., E-mail: fedorov_fs@daad-alumni.de [NanoTechProm Ltd., Saratov (Russian Federation); Saratov State Technical University, Saratov (Russian Federation)

2014-12-05

Highlights: • Quasi-static permittivity of potassium polytitanates compacts achieves 10{sup 4}–10{sup 5}. • Observed Maxwell–Wagner polarization attributes to layered structure of polytitanates. • The conductivity varies from 5 × 10{sup −2} to 10{sup −6}–10{sup −7} Sm/m in a wide range of temperatures. - Abstract: Titanates of alkali metals are widely applied materials as they are relatively low in cost and might be easily synthesized. They are utilized as adsorbents, catalysts, solid state electrolytes, superconductors. Here we report our results on electrical properties of the compacted amorphous potassium polytitanates powders. The electrical properties of the compacts were studied by means of complex impedance spectroscopy in a wide range of frequencies at different temperatures using two-electrode configuration. The frequency dependences of conductivity for the investigated potassium polytitanates compacts varies in the range from 5 × 10{sup −2} Sm/m (high frequencies, ion conductivity) up to 10{sup −6}–10{sup −7} Sm/m (low frequencies, electron conductivity) for a wide range of temperatures (19–150 °C). According to the results, at low frequencies quasi-static permittivity of the stabilized PPT compacts achieves high values of 10{sup 4}–10{sup 5}. This might be explained by Maxwell–Wagner polarization attributed to the layered structure of the potassium polytitanates particles containing potassium and hydronium ions together with crystallization water in the interlayer and is very promising for solid state electrolyte applications for moderate temperatures.

Crystal structure of the potassium-importing KdpFABC membrane complex

Energy Technology Data Exchange (ETDEWEB)

Huang, Ching-Shin; Pedersen, Bjørn Panyella; Stokes, David L.

2017-06-21

Cellular potassium import systems play a fundamental role in osmoregulation, pH homeostasis and membrane potential in all domains of life. In bacteria, the kdp operon encodes a four-subunit potassium pump that maintains intracellular homeostasis, cell shape and turgor under conditions in which potassium is limiting1. This membrane complex, called KdpFABC, has one channel-like subunit (KdpA) belonging to the superfamily of potassium transporters and another pump-like subunit (KdpB) belonging to the superfamily of P-type ATPases. Although there is considerable structural and functional information about members of both superfamilies, the mechanism by which uphill potassium transport through KdpA is coupled with ATP hydrolysis by KdpB remains poorly understood. Here we report the 2.9 Å X-ray structure of the complete Escherichia coli KdpFABC complex with a potassium ion within the selectivity filter of KdpA and a water molecule at a canonical cation site in the transmembrane domain of KdpB. The structure also reveals two structural elements that appear to mediate the coupling between these two subunits. Specifically, a protein-embedded tunnel runs between these potassium and water sites and a helix controlling the cytoplasmic gate of KdpA is linked to the phosphorylation domain of KdpB. On the basis of these observations, we propose a mechanism that repurposes protein channel architecture for active transport across biomembranes.
Parathyroid hormone impairs extrarenal potassium tolerance in the rat

International Nuclear Information System (INIS)

Sugarman, A.; Kahn, T.

1988-01-01

The effect of parathyroid hormone (PTH) on the extrarenal disposition of an acute potassium load was examined in acutely nephrectomized rats infused with KCl alone or in combination with PTH, with serial monitoring of plasma potassium every 10 min. The rise in plasma potassium concentration (ΔPK) in the PTH group was higher than control. PTH was then administered along with KCl to two groups of nephrectomized and acutely thyroparathyroidectomized (TPTX) rats in doses of 1 and 0.25 U · kg -1 · min -1 for 90 min. ΔPK with PTH in both groups was higher than TPTX control. The two higher doses of PTH resulted in a decrease in mean arterial pressure from their respective controls. A similar reduction in arterial pressure in three groups of nephrectomized rats by administration of hydralazine or nitroprusside or by acute blood loss did not change ΔPK subsequent to potassium infusion from that in control rats. Furthermore, the lowest dose of PTH did not lower arterial pressure from its respective control. Therefore, hypotension is not a cause for the PTH-induced potassium intolerance. Serum levels of insulin, aldosterone, catecholamines, calcium, plasma HCO 3 concentration, and pH were not different in PTH-infused vs. respective control rats. These data suggest that PTH impairs extrarenal potassium disposal in the rat. The effect of PTH may relate to enhanced calcium entry into cells
Empiric potassium supplementation and increased survival in users of loop diuretics.

Directory of Open Access Journals (Sweden)

Charles E Leonard

Full Text Available The effectiveness of the clinical strategy of empiric potassium supplementation in reducing the frequency of adverse clinical outcomes in patients receiving loop diuretics is unknown. We sought to examine the association between empiric potassium supplementation and 1 all-cause death and 2 outpatient-originating sudden cardiac death (SD and ventricular arrhythmia (VA among new starters of loop diuretics, stratified on initial loop diuretic dose.We conducted a one-to-one propensity score-matched cohort study using 1999-2007 US Medicaid claims from five states. Empiric potassium supplementation was defined as a potassium prescription on the day of or the day after the initial loop diuretic prescription. Death, the primary outcome, was ascertained from the Social Security Administration Death Master File; SD/VA, the secondary outcome, from incident, first-listed emergency department or principal inpatient SD/VA discharge diagnoses (positive predictive value = 85%.We identified 654,060 persons who met eligibility criteria and initiated therapy with a loop diuretic, 27% of whom received empiric potassium supplementation (N = 179,436 and 73% of whom did not (N = 474,624. The matched hazard ratio for empiric potassium supplementation was 0.93 (95% confidence interval, 0.89-0.98, p = 0.003 for all-cause death. Stratifying on initial furosemide dose, hazard ratios for empiric potassium supplementation with furosemide < 40 and ≥ 40 milligrams/day were 0.93 (0.86-1.00, p = 0.050 and 0.84 (0.79-0.89, p < 0.0001. The matched hazard ratio for empiric potassium supplementation was 1.02 (0.83-1.24, p = 0.879 for SD/VA.Empiric potassium supplementation upon initiation of a loop diuretic appears to be associated with improved survival, with a greater apparent benefit seen with higher diuretic dose. If confirmed, these findings support the use of empiric potassium supplementation upon initiation of a loop diuretic.
Immunological properties of gold nanoparticles.

Science.gov (United States)

Dykman, Lev A; Khlebtsov, Nikolai G

2017-03-01

In the past decade, gold nanoparticles have attracted strong interest from the nanobiotechnological community owing to the significant progress made in robust and easy-to-make synthesis technologies, in surface functionalization, and in promising biomedical applications. These include bioimaging, gene diagnostics, analytical sensing, photothermal treatment of tumors, and targeted delivery of various biomolecular and chemical cargos. For the last-named application, gold nanoparticles should be properly fabricated to deliver the cargo into the targeted cells through effective endocytosis. In this review, we discuss recent progress in understanding the selective penetration of gold nanoparticles into immune cells. The interaction of gold nanoparticles with immune cell receptors is discussed. As distinct from other published reviews, we present a summary of the immunological properties of gold nanoparticles. This review also summarizes what is known about the application of gold nanoparticles as an antigen carrier and adjuvant in immunization for the preparation of antibodies in vivo . For each of the above topics, the basic principles, recent advances, and current challenges are discussed. Thus, this review presents a detailed analysis of data on interaction of gold nanoparticles with immune cells. Emphasis is placed on the systematization of data over production of antibodies by using gold nanoparticles and adjuvant properties of gold nanoparticles. Specifically, we start our discussion with current data on interaction of various gold nanoparticles with immune cells. The next section describes existing technologies to improve production of antibodies in vivo by using gold nanoparticles conjugated with specific ligands. Finally, we describe what is known about adjuvant properties of bare gold or functionalized nanoparticles. In the Conclusion section, we present a short summary of reported data and some challenges and perspectives.
Electrocardiography and serum potassium before and after hemodialysis sessions

International Nuclear Information System (INIS)

Tarif, N.; Al-Wakeel, Jamal Saleh; Sulaimani, F.; Memon, Nawaz Ali; Al-Suwaida, Abdul Kareem; Yamani, H.; Bakhsh, Ahmed Jahangir

2008-01-01

This study was undertaken to assess potassium level and electrocardiographic (ECG) changes post hemodialysis and whether fall in potassium level during hemodialysis may potentiate cardiac arrythemia. We studied 21 chronic hemodialysis (HD) patients who had their serum electrolytes measured before and after dialysis session and ECG performed at the same time. The patients included 14 females and 7 males with a mean age of 53.1+-15.6 years and range from 26 to 81 years; 9 (43%) patients were diabetics. All the patients had been on dialysis for a minimum of 6 months each Pre-HD serum potassium levels had no correlation with any ECG parameters except a negative correlation with T wave amplitude r=-0.5, p=0.021. ECG parameters significantly changed post-HD; the T wave amplitude decreased and the R wave amplitude increased. A comparatively higher R wave significantly decreased the T to R wave ratio post dialysis. The QRS duration and QTc interval also increased significantly. The patients with post-HD serum potassium of 3.5 mmol/L had a higher R wave amplitude and a significantly less T to R wave ratio (11.8+-9.7 vs 6.4+-5.1, p=0.045 and 0.4+-0.38 vs 1.0+-0.97, p=0.049, respectively. In patients with serum potassium decrement of >2.0 mmol/L, the T to R wave ratio decreased significantly, 0.32+-0.21 vs 0.85+-0.26, p=0.023; The T wave amplitude decreased more than the rise in R wave. Multiple regression analysis did not reveal any relationship of pre or post HD ECG changes and serum potassium, serum calcium or net change in serum potassium post-HD. We conclude that post-HD serum potassium decrement results in a decrease in T to R wave ratio on ECG; this change may have an arrhythmogenic potential. (author)
Measurement of the isotope effect of the diffusion of silver and gold in gold and of silver in silver-gold alloys

International Nuclear Information System (INIS)

Wolter, D.

1974-01-01

The silver isotopes Ag 105 and Agsup(110m) and the gold isotopes Au 195 and Au 199 were used for isotope effect measurements. The isotope effect of the gold self-diffusion was measured on four monocrystals samples at about 850 0 C, that of silver in gold monocrystals at five different temperatures between 731 0 C and 1050 0 C. Furthermore, the isotope effect for silver at 904 0 C was measured on seven silver-gold alloys of varying silver concentration. The correlation factor was determined from the measurements. (HPOE/LH) [de
The giant Jiaodong gold province: The key to a unified model for orogenic gold deposits?

Directory of Open Access Journals (Sweden)

David I. Groves

2016-05-01

Full Text Available Although the term orogenic gold deposit has been widely accepted for all gold-only lode-gold deposits, with the exception of Carlin-type deposits and rare intrusion-related gold systems, there has been continuing debate on their genesis. Early syngenetic models and hydrothermal models dominated by meteoric fluids are now clearly unacceptable. Magmatic-hydrothermal models fail to explain the genesis of orogenic gold deposits because of the lack of consistent spatially – associated granitic intrusions and inconsistent temporal relationships. The most plausible, and widely accepted, models involve metamorphic fluids, but the source of these fluids is hotly debated. Sources within deeper segments of the supracrustal successions hosting the deposits, the underlying continental crust, and subducted oceanic lithosphere and its overlying sediment wedge all have their proponents. The orogenic gold deposits of the giant Jiaodong gold province of China, in the delaminated North China Craton, contain ca. 120 Ma gold deposits in Precambrian crust that was metamorphosed over 2000 million years prior to gold mineralization. The only realistic source of fluid and gold is a subducted oceanic slab with its overlying sulfide-rich sedimentary package, or the associated mantle wedge. This could be viewed as an exception to a general metamorphic model where orogenic gold has been derived during greenschist- to amphibolite-facies metamorphism of supracrustal rocks: basaltic rocks in the Precambrian and sedimentary rocks in the Phanerozoic. Alternatively, if a holistic view is taken, Jiaodong can be considered the key orogenic gold province for a unified model in which gold is derived from late-orogenic metamorphic devolatilization of stalled subduction slabs and oceanic sediments throughout Earth history. The latter model satisfies all geological, geochronological, isotopic and geochemical constraints but the precise mechanisms of auriferous fluid release, like many
Impact of reduced atmospheric CO2 and varied potassium supply on carbohydrate and potassium distribution in grapevine and grape berries (Vitis vinifera L.).

Science.gov (United States)

Coetzee, Zelmari A; Walker, Rob R; Deloire, Alain J; Barril, Célia; Clarke, Simon J; Rogiers, Suzy Y

2017-11-01

To assess the robustness of the apparent sugar-potassium relationship during ripening of grape berries, a controlled-environment study was conducted on Shiraz vines involving ambient and reduced (by 34%) atmospheric CO 2 concentrations, and standard and increased (by 67%) soil potassium applications from prior to the onset of ripening. The leaf net photoassimilation rate was decreased by 35% in the reduced CO 2 treatment. The reduction in CO 2 delayed the onset of ripening, but at harvest the sugar content of the berry pericarp was similar to that of plants grown in ambient conditions. The potassium content of the berry pericarp in the reduced CO 2 treatment was however higher than for the ambient CO 2 . Berry potassium, sugar and water content were strongly correlated, regardless of treatments, alluding to a ternary link during ripening. Root starch content was lower under reduced CO 2 conditions, and therefore likely acted as a source of carbohydrates during berry ripening. Root carbohydrate reserve replenishment could also have been moderated under reduced CO 2 at the expense of berry ripening. Given that root potassium concentration was less in the vines grown in the low CO 2 atmosphere, these results point toward whole-plant fine-tuning of carbohydrate and potassium partitioning aimed at optimising fruit ripening. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
Facts and Fantasies about Gold

OpenAIRE

Klement, Joachim

2015-01-01

Due to the increasing popularity of gold as an investment the demand for effective risk management techniques for gold investments has increased as well. In this paper we analyze several drivers of the price of gold that have been proposed in the past. Our analysis indicates that short-term volatility of the price of gold remains rather unpredictable with many of the explanations like the fund flows in physical gold ETF either unreliable or unstable over time. Our analysis suggests that there...
Occurrences of dendritic gold at the McLaughlin Mine hot-spring gold deposit

Science.gov (United States)

Sherlock, R. L.; Lehrman, N. J.

1995-06-01

Two styles of gold dendrites are variably developed at the McLaughlin Mine. The most abundant occurrence is hosted by amber-coloured hydrocarbon-rich opal. Silica likely precipitated from a boiling hydrothermal fluid and complexed with immiscible hydrocarbons forming an amorphous hydrocarbon-silica phase. This phase likely scavenged particulate gold by electrostatic attraction to the hydrocarbon-silica phase. The dendritic nature of the gold is secondary and is the result of dewatering of the amorphous hydrocarbon-silica phase and crystallization of gold into syneresis fractures. The second style of dendritic gold is hosted within vein swarms that focused large volumes of fluid flow. The dendrites occur along with hydrocarbon-rich silica at the upper contact of the vein margins which isolated the dendrites allowing sufficient time for them to grow. In a manner similar to the amber-coloured opal, the dendrites may have formed by scavenging particulate gold by electrostatic attraction to the hydrocarbon-silica phase.
Electrocatalytic glucose oxidation at gold and gold-carbon nanoparticulate film prepared from oppositely charged nanoparticles

International Nuclear Information System (INIS)

Karczmarczyk, Aleksandra; Celebanska, Anna; Nogala, Wojciech; Sashuk, Volodymyr; Chernyaeva, Olga; Opallo, Marcin

2014-01-01

Graphical abstract: - Highlights: • Gold nanoparticulate film electrodes were prepared by layer-by-layer method from oppositely charged nanoparticles. • Positively charged nanoparticles play dominant role in glucose oxidation in alkaline solution. • Gold and gold-carbon nanoparticulate film electrodes exhibit similar glucose oxidation current and onset potential. - Abstract: Electrocatalytic oxidation of glucose was studied at nanoparticulate gold and gold-carbon film electrodes. These electrodes were prepared by a layer-by-layer method without application of any linker molecules. Gold nanoparticles were stabilized by undecane thiols functionalized by trimethyl ammonium or carboxylate groups, whereas the carbon nanoparticles were covered by phenylsulfonate functionalities. The gold nanoparticulate electrodes were characterized by UV-vis and XPS spectroscopy, atomic force microscopy and voltammetry, before and after heat-treatment. Heat-treatment facilitates the aggregation of the nanoparticles and affects the structure of the film. The comparison of the results obtained with film electrodes prepared from gold nanoparticles with the same charge and with gold-carbon nanoparticulate electrodes, proved that positively charged nanoparticles are responsible for the high electrocatalytic activity, whereas negatively charged ones act rather as a linker of the film
The Ketogenic Diet and Potassium Channel Function

Science.gov (United States)

2015-11-01

1 AWARD NUMBER: W81XWH-13-1-0463 TITLE: The Ketogenic Diet and Potassium Channel Function PRINCIPAL INVESTIGATOR: Dr. Geoffrey Murphy...NUMBER The Ketogenic Diet and Potassium Channel Function 5b. GRANT NUMBER W81XWH-13-1-0463 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Geoffrey Murphy...The overall objective of this Discovery Award was to explore the hypothesis the ketogenic diet (KD) regulates neuronal excitability by influencing
Relationship between potassium intake and radiocesium retention in the reindeer

International Nuclear Information System (INIS)

Holleman, D.F.; Luick, J.R.

1975-01-01

The effect of dietary potassium on radiocesium retention was studied in reindeer fed winter diets of lichens. Potassium added to the diet markedly decreased radiocesium retention; this suggests that seasonal changes in cesium retention observed earlier in reindeer might be caused largely by nutritional factors. Data indicate that a 20-fold increase in dietary potassium results in a 2-fold decrease in radiocesium retention
Dielectric properties of a potassium nitrate–ammonium nitrate system

OpenAIRE

Alexey Yu. Milinskiy; Anton A. Antonov

2015-01-01

Potassium nitrate has a rectangular hysteresis loop and is thought to be a promising material for non-volatile ferroelectric memory. However, its polar phase is observed in a narrow temperature range. This paper deals with an effect of ammonium nitrate NH4NO3 on the dielectric properties of potassium nitrate. Thermal dependencies of the linear dielectric permittivity ε and the third-harmonic coefficient g3 for potassium nitrate and polycrystalline binary (KNO3)1–x(NH4NO3)x system (x = 0.025, ...
A non-diazo approach to α-oxo gold carbenes via gold-catalyzed alkyne oxidation.

Science.gov (United States)

Zhang, Liming

2014-03-18

For the past dozen years, homogeneous gold catalysis has evolved from a little known topic in organic synthesis to a fully blown research field of significant importance to synthetic practitioners, due to its novel reactivities and reaction modes. Cationic gold(I) complexes are powerful soft Lewis acids that can activate alkynes and allenes toward efficient attack by nucleophiles, leading to the generation of alkenyl gold intermediates. Some of the most versatile aspects of gold catalysis involve the generation of gold carbene intermediates, which occurs through the approach of an electrophile to the distal end of the alkenyl gold moiety, and their diverse transformations thereafter. On the other hand, α-oxo metal carbene/carbenoids are highly versatile intermediates in organic synthesis and can undergo various synthetically challenging yet highly valuable transformations such as C-H insertion, ylide formation, and cyclopropanation reactions. Metal-catalyzed dediazotizations of diazo carbonyl compounds are the principle and most reliable strategy to access them. Unfortunately, the substrates contain a highly energetic diazo moiety and are potentially explosive. Moreover, chemists need to use energetic reagents to prepare them, putting further constrains on operational safety. In this Account, we show that the unique access to the gold carbene species in homogeneous gold catalysis offers an opportunity to generate α-oxo gold carbenes if both nucleophile and electrophile are oxygen. Hence, this approach would enable readily available and safer alkynes to replace hazardous α-diazo carbonyl compounds as precursors in the realm of gold carbene chemistry. For the past several years, we have demonstrated that alkynes can indeed effectively serve as precursors to versatile α-oxo gold carbenes. In our initial study, we showed that a tethered sulfoxide can be a suitable oxidant, which in some cases leads to the formation of α-oxo gold carbene intermediates. The
A Non-Diazo Approach to α-Oxo Gold Carbenes via Gold-Catalyzed Alkyne Oxidation

Science.gov (United States)

2015-01-01

For the past dozen years, homogeneous gold catalysis has evolved from a little known topic in organic synthesis to a fully blown research field of significant importance to synthetic practitioners, due to its novel reactivities and reaction modes. Cationic gold(I) complexes are powerful soft Lewis acids that can activate alkynes and allenes toward efficient attack by nucleophiles, leading to the generation of alkenyl gold intermediates. Some of the most versatile aspects of gold catalysis involve the generation of gold carbene intermediates, which occurs through the approach of an electrophile to the distal end of the alkenyl gold moiety, and their diverse transformations thereafter. On the other hand, α-oxo metal carbene/carbenoids are highly versatile intermediates in organic synthesis and can undergo various synthetically challenging yet highly valuable transformations such as C–H insertion, ylide formation, and cyclopropanation reactions. Metal-catalyzed dediazotizations of diazo carbonyl compounds are the principle and most reliable strategy to access them. Unfortunately, the substrates contain a highly energetic diazo moiety and are potentially explosive. Moreover, chemists need to use energetic reagents to prepare them, putting further constrains on operational safety. In this Account, we show that the unique access to the gold carbene species in homogeneous gold catalysis offers an opportunity to generate α-oxo gold carbenes if both nucleophile and electrophile are oxygen. Hence, this approach would enable readily available and safer alkynes to replace hazardous α-diazo carbonyl compounds as precursors in the realm of gold carbene chemistry. For the past several years, we have demonstrated that alkynes can indeed effectively serve as precursors to versatile α-oxo gold carbenes. In our initial study, we showed that a tethered sulfoxide can be a suitable oxidant, which in some cases leads to the formation of α-oxo gold carbene intermediates. The
Potassium-phosphorus relationships in cotton (gossypium hirsutum L.) as affected by potassium nutrition

International Nuclear Information System (INIS)

Makhdum, M.I.; Ashraf, M.

2007-01-01

Field studies were undertaken to determine the interrelationship between potassium (K+) concentration in various organs of plant and phosphorus (P) content as influenced by K-nutrition in cotton. The experiment was conducted on Miani soil series silt loam and classified as Calcaric Cambisols, fine silty, mixed Hyperthermic Fluventic Haplocambids. The treatments consisted .of (a) four cotton (Gossypium hirsutum L.) cultivars (CI.M-448, CIM-IIOO, Karishma, S-12); and (b) four potassium fertilizer doses (0, 62.5, 125.0, 250.0 kg K ha-l). The design of experiment was split plot (main: cultivars, sub-plot: K-doses). The plant samples were collected at five stages of growth, i.e., first flower bud., first flower, peak flowering, first boll split and maturity. The various parts of plants were analyzed for phosphorus and potassium concentration at various stages of growth. Phosphorus concentration in leaves, stems, burs, seed and lint decreased with concurrent increase in K-doses. Crop maintained 0.22% phosphorus concentration in leaf tissues at first flower bud and dropped to 0.11% at maturity. Cultivars differed greatly amongst themselves in terms of maintaining P content in their different parts. Averaged across K-doses, cv. CIM-448 maintained the highest P content in all parts than other cultivars. There was a negative and significant correlation co-efficient between K and P concentration in various parts of the plant. The study demonstrated antagonistic interaction between K+ and P in cotton plant under irrigated conditions. (author)
Summary of gold nanoparticles obtained by reduction Au3+

International Nuclear Information System (INIS)

Corzo Lucioni, Alberto

2012-01-01

In the present investigation were synthesized nanoparticles (NPs) of gold by oxidation-reduction reactions at boiling temperature, starting from dilute solutions of acid tetrachloroauric: H[AuCl 4 ].3H 2 O as a precursor in the presence of organic reducing agents such as trisodium citrate: Na 3 C 6 H 5 O 7 .2H 2 O; potassium sodium tartrate: KNaC 4 H 4 O 6 .4H 2 O and sodium borohydride: inorganic reducing agent NaBH 4 . With the aim of evaluating the particle size according to the type of reducing agent, is designed a series of experiments in which the reducing agent is changed, keeping it constant concentrations, but varying the concentration of H[AuCl 4 ]. The particle size and the absorbance of the plasmon Au were measured in a particle size analyzer and a UV - visible, respectively. In turn, the effect of pH variation on the size of the NP Au, maintaining concentrations of H [AuCl 4 ] constant and reducing agent trisodium citrate, at different pH values under the same conditions. (author).
Surface-stabilized gold nanocatalysts

Science.gov (United States)

Dai, Sheng [Knoxville, TN; Yan, Wenfu [Oak Ridge, TN

2009-12-08

A surface-stabilized gold nanocatalyst includes a solid support having stabilizing surfaces for supporting gold nanoparticles, and a plurality of gold nanoparticles having an average particle size of less than 8 nm disposed on the stabilizing surfaces. The surface-stabilized gold nanocatalyst provides enhanced stability, such as at high temperature under oxygen containing environments. In one embodiment, the solid support is a multi-layer support comprising at least a first layer having a second layer providing the stabilizing surfaces disposed thereon, the first and second layer being chemically distinct.
A halogen-free synthesis of gold nanoparticles using gold(III) oxide

International Nuclear Information System (INIS)

Sashuk, Volodymyr; Rogaczewski, Konrad

2016-01-01

Gold nanoparticles are one of the most used nanomaterials. They are usually synthesized by the reduction of gold(III) chloride. However, the presence of halide ions in the reaction mixture is not always welcome. In some cases, these ions have detrimental influence on the morphology and structure of resulting nanoparticles. Here, we present a simple and halogen-free procedure to prepare gold nanoparticles by reduction of gold(III) oxide in neat oleylamine. The method provides the particles with an average size below 10 nm and dispersity of tens of percent. The process of nanoparticle formation was monitored using UV–Vis spectroscopy. The structure and chemical composition of the nanoparticles was determined by SEM, XPS and EDX. We also proposed the mechanism of reduction of gold(III) oxide based on MS, IR and NMR data. Importantly, the synthetic protocol is general and applicable for the preparation of other coinage metal nanoparticles from the corresponding metal oxides. For instance, we demonstrated that the absence of halogen enables efficient alloying of metals when preparing gold–silver bimetallic nanoparticles.

Structure and bonding in gold compounds

International Nuclear Information System (INIS)

Parish, R.V.

1988-01-01

Recent developments in chemical applications of 197 Au Moessbauer spectroscopy are reviewed. For gold(I) and gold(III), systematic variations in isomer shift and quadrupole splitting are seen as the ligands are changed; the effects of change in coordination number of the gold atoms are also systematic. Data for gold(II) systems involving gold-gold bonds lie between those for corresponding gold(I) and gold(III) materials, showing a small increase in isomer shift and a larger increase in quadrupole splitting as the oxidation state decreases; these trends are explained in terms of the structures. Data for mixed-metal cluster compounds are much more sensitive to structural effects than in homonuclear clusters. Both sets of data show systematic changes with increase in the number of metal atoms to which the gold atom is bound. The connectivity also influences the recoil-free fraction. (orig.)
Nutritional potassium requirement for laying Japanese quails

Directory of Open Access Journals (Sweden)

Fernando Guilherme Perazzo Costa

2011-12-01

Full Text Available The objective of this study was to evaluate the potassium requirement for laying Japanese quails. Two hundred and forty quails were distributed in a randomized block design, with five treatments and six replicates, with eight birds each. The treatments consisted of a basal diet deficient in potassium (K (2.50 g/kg, supplemented with potassium carbonate, to replace the inert, to reach levels of 2.50, 3.50, 4.50, 5.50 and 6.50 (g/kg of K in the diet. There was a quadratic effect of K levels on feed intake, egg production, egg mass and feed conversion per egg mass and per egg dozen, estimating the requirements of 4.26, 4.41, 4.38, 4.43 and 4.48 (g/kg of K diet, respectively. There was no significant effect on the levels of K in the diet on egg weight, albumen weight, percentage of yolk or shell and yolk color. However, yolk and shell weights reduced and the albumen percentage increased linearly with increasing levels of K in the diet. Despite the reduction of shell weight, the increased levels of K did not influence the specific gravity and shell thickness. The use of 4.41 g/kg of potassium is recommended in the diet for laying Japanese quails.
Potassium cardioplegia: early assessment by radionuclide ventriculography

International Nuclear Information System (INIS)

Ellis, R.J.; Born, M.; Feit, T.; Ebert, P.A.

1978-01-01

Left ventricular function was evaluated by single pass /sup 99m/Tc radionuclide ventriculography when potassium cardioplegia was combined with hypothermia. In 35 patients undergoing myocardial revascularization (3 CABG/patient) in which potassium cardioplegia at 4 0 C was used, no patient developed a myocardial infarction either by electrocardiogram or /sup 99m/Tc pyrophosphate imaging in the postoperative period. In 22 patients, aortic cross-clamp time was greater than 60 min, and the ejection fraction by the single pass radionuclide technique was 50% preoperatively and 53% postoperatively (NS). Wall motion in the single RAO view was not worse postoperatively. No patient required any inotropic agents in the immediate postoperative period. It appears that no significant ventricular impairment occurred in the immediate postoperative period (48 to 72 hours) when potassium cardioplegia combined with hypothermia was used for a 60-minute period
Balance of unidirectional monovalent ion fluxes in cells undergoing apoptosis: why does Na+/K+ pump suppression not cause cell swelling?

Science.gov (United States)

Yurinskaya, Valentina E; Rubashkin, Andrey A; Vereninov, Alexey A

2011-05-01

Cells dying according to the apoptotic program, unlike cells dying via an unprogrammed mode, are able to avoid swelling and osmotic bursting with membrane disruption.There are indications that apoptosis is accompanied by suppression of the Na+/K+ pump and changes in the K+ and Cl− channels. It remains unclear how ion fluxes through individual ion pathways are integrated so as to induce loss of intracellular ions and concomitant apoptotic volume decrease. A decrease in activity of the sodium pump during apoptosis should cause cell swelling rather than shrinkage. We have made the first systemic analysis of the monovalent ion flux balance in apoptotic cells. Experimental data were obtained for human U937 cells treated with staurosporine for 4–5 h, which is known to induce apoptosis. The data include cellular Cl− content and fluxes, K+, Na+, water content and ouabain-sensitive and -resistant Rb+ fluxes.Unidirectional monovalent ion fluxeswere calculated using these data and a cell model comprising the double Donnan system with the Na+/K+ pump, Cl−, K+, Na+ channels, the Na+–K+–2Cl−cotransporter (NKCC), the Na+–Cl− cotransporter (NC), and the equivalent Cl−/Cl− exchange.Apoptotic cell shrinkage was found to be caused, depending on conditions, either by an increase in the integral channel permeability of membrane for K+ or by suppression of the pump coupledwith a decrease in the integral channel permeability of membrane for Na+. The decrease in the channel permeability of membrane for Na+ plays a crucial role in cell dehydration in apoptosis accompanied by suppression of the pump. Supplemental Table S1 is given for easy calculating flux balance under specified conditions.
Knowledge-driven GIS modeling technique for gold exploration, Bulghah gold mine area, Saudi Arabia

Directory of Open Access Journals (Sweden)

Ahmed A. Madani

2011-12-01

Full Text Available This research aims to generate a favorability map for gold exploration at the Bulghah gold mine area using integration of geo-datasets within a GIS environment. Spatial data analyses and integration of different geo-datasets are carried out based on knowledge-driven and weighting technique. The integration process involves the weighting and scoring of different layers affecting the gold mineralization at the study area using the index overlay method within PCI Geomatica environment. Generation of the binary predictor maps for lithology, lineaments, faults and favorable contacts precede the construction of the favorability map. About 100 m buffer zones are generated for favorable contacts, lineaments and major faults layers. Internal weighting is assigned to each layer based on favorability for gold mineralization. The scores for lithology, major faults, lineaments and favorable contacts layers in the constructed favorability map are 50%, 25%, 10% and 15%, respectively. Final favorability map for the Bulghah gold mine area shows the recording of two new sites for gold mineralization located at the northern and southern extensions of tonalite–diorite intrusions. The northern new site is now exploited for gold from the Bulghah North mine. The southern new site is narrow and small; its rocks resemble those of the Bulghah gold mine.
Ancient Systems of Sodium/Potassium Homeostasis as Predecessors of Membrane Bioenergetics.

Science.gov (United States)

Dibrova, D V; Galperin, M Y; Koonin, E V; Mulkidjanian, A Y

2015-05-01

Cell cytoplasm of archaea, bacteria, and eukaryotes contains substantially more potassium than sodium, and potassium cations are specifically required for many key cellular processes, including protein synthesis. This distinct ionic composition and requirements have been attributed to the emergence of the first cells in potassium-rich habitats. Different, albeit complementary, scenarios have been proposed for the primordial potassium-rich environments based on experimental data and theoretical considerations. Specifically, building on the observation that potassium prevails over sodium in the vapor of inland geothermal systems, we have argued that the first cells could emerge in the pools and puddles at the periphery of primordial anoxic geothermal fields, where the elementary composition of the condensed vapor would resemble the internal milieu of modern cells. Marine and freshwater environments generally contain more sodium than potassium. Therefore, to invade such environments, while maintaining excess of potassium over sodium in the cytoplasm, primordial cells needed means to extrude sodium ions. The foray into new, sodium-rich habitats was the likely driving force behind the evolution of diverse redox-, light-, chemically-, or osmotically-dependent sodium export pumps and the increase of membrane tightness. Here we present a scenario that details how the interplay between several, initially independent sodium pumps might have triggered the evolution of sodium-dependent membrane bioenergetics, followed by the separate emergence of the proton-dependent bioenergetics in archaea and bacteria. We also discuss the development of systems that utilize the sodium/potassium gradient across the cell membranes.
Functional diversity of potassium channel voltage-sensing domains.

Science.gov (United States)

Islas, León D

2016-01-01

Voltage-gated potassium channels or Kv's are membrane proteins with fundamental physiological roles. They are composed of 2 main functional protein domains, the pore domain, which regulates ion permeation, and the voltage-sensing domain, which is in charge of sensing voltage and undergoing a conformational change that is later transduced into pore opening. The voltage-sensing domain or VSD is a highly conserved structural motif found in all voltage-gated ion channels and can also exist as an independent feature, giving rise to voltage sensitive enzymes and also sustaining proton fluxes in proton-permeable channels. In spite of the structural conservation of VSDs in potassium channels, there are several differences in the details of VSD function found across variants of Kvs. These differences are mainly reflected in variations in the electrostatic energy needed to open different potassium channels. In turn, the differences in detailed VSD functioning among voltage-gated potassium channels might have physiological consequences that have not been explored and which might reflect evolutionary adaptations to the different roles played by Kv channels in cell physiology.
Excited state fluorescence quenching of the U O2++ ion by monovalent anions

International Nuclear Information System (INIS)

Santarine, G.A.

1987-01-01

The reactions of the Uranyl ion U O 2 ++ in the excited state with the monovalent inorganic ions N O 3 - and I O 3 - in aqueous solutions at normal temperature were studied, using three techniques: Fluorescence in the steady state - Flash photolysis - Fluorescence decay after excitation. With increasing concentration of these ions it was observed a decrease in the normalized intensity and a decrease in the decay time of the fluorescence of the Uranyl ion in the solution and a corresponding appearance of the radicals N O 3 . or I O 3 . . In each case the radical was identified by its optical absorption spectrum. These results suggest that the quenching of fluorescence of the Uranyl ion in each case is owing to an electron transfer reaction. In the case of the Nitrate ion the transfer may occur after the formation of an ionic par (U O 2 + ...N O 3 ) in the ground state. Evidence for static quenching in the system Uranyl iodate was not forthcoming. A mechanism for the determination of the velocity constant (probability per ion pair per unit time) is proposed for each of the systems. (author)
Radiolysis of titanium potassium oxalate in aqueous solution. [. gamma. rays

Energy Technology Data Exchange (ETDEWEB)

Bundo, Y; Ono, I [Industrial Research Inst. of Kanagawa Prefecture, Yokohama (Japan); Ogawa, T

1975-01-01

The dissolution state of titanium potassium oxalate in aqueous solution is different according to the pH. The yellowish brown titanium complex produced by the reaction of titanium potassium oxalate and hydrogen peroxide seems to be different in its structure according to the pH. Considering these points, gamma-ray irradiation was carried out on the sample by dissolving titanium potassium oxalate in purified water under the conditions of oxygen saturation and nitrogen saturation, and the relation between irradiation dose and the production of titanium complex was determined. On the basis of the experimental result, the mechanism of forming hydrogen peroxide was presumed. The radiation source used was 2,000 Ci of /sup 60/Co. For photometric analysis, a 139 type photoelectric spectrophotometer of Hitachi Ltd. was used. From the experimental results, in neutral water, titanium potassium oxalate exists in the state that two oxalic acid ions are coordinated to titanyl ion, while in case of the pH lowered by the addition of sulfuric acid, it can exist in the state that one oxalic acid ion is coordinated to titanyl ion. The yield of hydrogen peroxide produced by irradiating titanium potassium oxalate aqueous solution with gamma-ray is the sum of the molecular product from water and the radiolysis product from titanium potassium oxalate.
The mode of occurrence of gold and silver in the Dominian Reef and their response to cyanidation after pressure leading

International Nuclear Information System (INIS)

Glatthaar, C.W.; Feather, C.E.

1985-01-01

Gold and silver in the Upper Reef of the Dominion Group in the Afrikander Lease area occur in several minerals. Native gold, electrum, and amalgam are the main gold bearers, whereas silver, in addition to being present in the above alloys, is also represented by native silver, in mercurian silver (arquerite), acanthite, stromeyerite, and a bismuth-silver sulphide (schaba-chite or pavionite), and in solid solution in galena. Only minute quantities of these silver-bearing minerals were found, and attempts to evaluate their relative abundances in the ore proved to be difficult. It was possible, however, by use of an electron microprobe, to quantify the silver contents in electrum, amalgam, mercurian silver, and galena. Mass-balance studies based on the calculated galena content suggest that about half of the total silver is associated with galena in solid solution. In practice, the uranium present in the conglomerates of the Dominion Group is extracted first. Because of the refractory nature of the uranium-bearing minerals, a leach at high temperature and high pressure is recommended. While this pressure leach is beneficial to the subsequent cyanidation of gold, a large proportion of the silver present is rendered refractory. The poor recoveries of silver are believed to be due close association of silver and galena. It is believed that silver is released during the dissolution of galena, acanthite, other silver sulphides, and native silver, and subsequently precipitated either as an insoluble complex silver-iron sulphate (argentojarosite) or in solid solution in jarosite (potassium-iron sulphate). Neither compound is amenable to cyanidation. A mixture of plumbojarosite (lead-iron sulphate) and jarosite were seen to form protective coatings on galena particles, and may occlude other silver-bearing minerals in the same manner. In contrast, finely divided gold particles are liberated from pyrite and other minerals during pressure leaching and become readily available to
Determination of Gold from Gold Matrix of North Western Nigeria ...

African Journals Online (AJOL)

The research paper presents analytical results of Au, Mn and V concentrations of some Nigerian gold ores using two techniques: epithermal neutron activation analysis (ENAA) and proton induced X-ray emission (PIXE). Fourteen samples were collected from gold fields of North Western Nigeria, prepared separately to a ...
21 CFR 520.1696b - Penicillin G potassium in drinking water.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Penicillin G potassium in drinking water. 520....1696b Penicillin G potassium in drinking water. (a) Specifications. When reconstituted, each milliliter contains penicillin G potassium equivalent to 20,000, 25,000, 40,000, 50,000, 80,000, or 100,000 units of...
Effect of potassium-salt muds on gamma ray, and spontaneous potential measurements

International Nuclear Information System (INIS)

Cox, J.W.; Raymer, L.L.

1976-01-01

Interpretations of the gamma ray and Spontaneous Potential curves generally assume the presence of sodium chloride as the dominant salt in both the formation water and the mud filtrate. However, potassium-salt muds are increasingly being used by the oil industry. The potassium cation is significantly different from the sodium cation in its radioactive and electrochemical properties. Natural potassium contains a radioactive isotope which emits gamma rays. Thus, the presence of potassium salts in the mud system may contribute to Gamma-Ray tool response. Since the Gamma Ray is used quantitatively in many geological sequences as an indicator of clay content, a way to correct for the effect of potassium in the mud column is desirable. Correction methods and charts based on laboratory measurements and field observations are presented. The effect of temperature on the resistivity of potassium muds is also briefly discussed. From data available, it appears to be similar to that for NaCl muds. On the bases of field observations and laboratory work, the electrochemical properties of potassium-chloride and potassium-carbonate muds and mud filtrates are discussed. Activity relationships are proposed, and the influence of these salts on the SP component potentials--namely, the liquid-junction, membrane, and bi-ionic potentials--is described. Several field examples are presented
Evaluating the effect of potassium on cellulose pyrolysis reaction kinetics

International Nuclear Information System (INIS)

Trendewicz, Anna; Evans, Robert; Dutta, Abhijit; Sykes, Robert; Carpenter, Daniel; Braun, Robert

2015-01-01

This paper proposes modifications to an existing cellulose pyrolysis mechanism in order to include the effect of potassium on product yields and composition. The changes in activation energies and pre-exponential factors due to potassium were evaluated based on the experimental data collected from pyrolysis of cellulose samples treated with different levels of potassium (0–1% mass fraction). The experiments were performed in a pyrolysis reactor coupled to a molecular beam mass spectrometer (MBMS). Principal component analysis (PCA) performed on the collected data revealed that cellulose pyrolysis products could be divided into two groups: anhydrosugars and other fragmentation products (hydroxyacetaldehyde, 5-hydroxymethylfurfural, acetyl compounds). Multivariate curve resolution (MCR) was used to extract the time resolved concentration score profiles of principal components. Kinetic tests revealed that potassium apparently inhibits the formation of anhydrosugars and catalyzes char formation. Therefore, the oil yield predicted at 500 ° C decreased from 87.9% from cellulose to 54.0% from cellulose with 0.5% mass fraction potassium treatment. The decrease in oil yield was accompanied by increased yield of char and gases produced via a catalyzed dehydration reaction. The predicted char and gas yield from cellulose were 3.7% and 8.4%, respectively. Introducing 0.5% mass fraction potassium treatment resulted in an increase of char yield to 12.1% and gas yield to 33.9%. The validation of the cellulose pyrolysis mechanism with experimental data from a fluidized-bed reactor, after this correction for potassium, showed good agreement with our results, with differences in product yields of up to 5%
Influence of Potassium on Sapric Peat under Different Environmental Conditions

Science.gov (United States)

Tajuddin, Syafik Akmal Mohd; Rahman, Junita Abdul; Rahim, Nor Haakmal Abd; Saphira Radin Mohamed, Radin Maya; Saeed Abduh Algheethi, Adel Ali, Dr

2018-04-01

Potassium is mainly present in soil in the natural form known as the K-bearing mineral. Potassium is also available in fertilizer as a supplement to plants and can be categorized as macronutrient. The application of potassium improves the texture and structure of the soil beside to improves plant growth. The main objective of this study was to determine the concentration of potassium in sapric peat under different conditions. Physical model was used as a mechanism for the analysis of the experimental data using a soil column as an equipment to produce water leaching. In this investigation, there were four outlets in the soil column which were prepared from the top of the column to the bottom with the purpose of identifying the concentration of potassium for each soil level. The water leaching of each outlet was tested using atomic absorption spectroscopy (AAS). The results obtained showed that the highest concentrations of potassium for flush condition at outlet 4 was 13.58 ppm. Similarly, sapric under rainwater condition recorded the highest value of 13.32 and 12.34 ppm respectively at outlet 4 for wet and dry condition. However, the difference in Sapric, rainwater and fertilizer category showed that the highest value for the wet condition was achieved at outlet 2 with 13.99 ppm while highest value of 14.82 ppm was obtained for the dry condition at the outlet 3. It was concluded that the outlets in the soil column gave a detailed analysis of the concentration of potassium in the soil which was influenced by the environmental conditions.
Serum Sodium and Potassium Levels in Cerebro-vascular Accident Patients.

Science.gov (United States)

Farahmand, Farahmand; Choobi Anzali, Babak; Heshmat, Ramin; Ghafouri, Hamed-Basir; Hamedanchi, Sepehr

2013-05-01

We aim to assess serum sodium and potassium levels in patients with different types of cerebro-vascular accidents (CVA) in comparison to control group. A comparative cross-sectional study conducted on patients admitted to the emergency department from January to August 2012. Control group consisted of patients admitted to emergency department due to common cold, urinary tract infection, low back pain, cluster, and tension headache or migraine. Serum sodium and potassium levels were measured via standard laboratory methods. There were 77 patients in control group and 78 in CVA group. Forty nine patients from the CVA group had ischemic CVA, 11 had hemorrhagic CVA and 18 suffered a transient ischemic attack (TIA). Serum sodium level in control group was significantly lower than in patients with TIA, ischemic CVA, and hemorrhagic CVA (P < 0.001). Serum potassium level in control group was higher than patients with TIA, ischemic CVA, and hemorrhagic CVA (P < 0.001). Patients with hemorrhagic CVA showed significantly lower serum potassium level than patients with TIA and ischemic CVA (P < 0.001). Correspondingly, it was observed that serum sodium to potassium ratio was higher in patients with TIA, ischemic CVA, and hemorrhagic CVA (P < 0.001). In patients with hemorrhagic CVA serum sodium to potassium ratio was higher when compared to patients with TIA and ischemic CVA (P < 0.001). This study shows that higher serum sodium and lower serum potassium level may be associated with higher incidence of CVA. Further studies are paramount to elucidate the role of serum electrolyte levels in vascular events.
Effectiveness of Monovalent and Pentavalent Rotavirus Vaccines in Guatemala.

Science.gov (United States)

Gastañaduy, Paul A; Contreras-Roldán, Ingrid; Bernart, Chris; López, Beatriz; Benoit, Stephen R; Xuya, Marvin; Muñoz, Fredy; Desai, Rishi; Quaye, Osbourne; Tam, Ka Ian; Evans-Bowen, Diana K; Parashar, Umesh D; Patel, Manish; McCracken, John P

2016-05-01

Concerns remain about lower effectiveness and waning immunity of rotavirus vaccines in resource-poor populations. We assessed vaccine effectiveness against rotavirus in Guatemala, where both the monovalent (RV1; 2-dose series) and pentavalent (RV5; 3-dose series) vaccines were introduced in 2010. A case-control evaluation was conducted in 4 hospitals from January 2012 to August 2013. Vaccine status was compared between case patients (children with laboratory-confirmed rotavirus diarrhea) and 2 sets of controls: nondiarrhea "hospital" controls (matched by birth date and site) and nonrotavirus "test-negative" diarrhea controls (adjusted for age, birth month/year, and site). Vaccine effectiveness ([1 - odds ratio of vaccination] × 100%) was computed using logistic regression models. We evaluated 213 case patients, 657 hospital controls, and 334 test-negative controls. Effectiveness of 2-3 doses of a rotavirus vaccine against rotavirus requiring emergency department visit or hospitalization was 74% (95% confidence interval [CI], 58%-84%) with hospital controls, and 52% (95% CI, 26%-69%) with test-negative controls. Using hospital controls, no significant difference in effectiveness was observed between infants 6-11 months (74% [95% CI, 18%-92%]) and children ≥12 months of age (71% [95% CI, 44%-85%]) (P= .85), nor between complete courses of RV1 (63% [95% CI, 23%-82%]) and RV5 (69% [95% CI, 29%-87%]) (P= .96). An uncommon G12P[8] strain, partially heterotypic to strains in both vaccines, was identified in 89% of cases. RV1 and RV5 were similarly effective against severe rotavirus diarrhea caused by a heterotypic strain in Guatemala. This supports broader implementation of rotavirus vaccination in low-income countries where >90% global deaths from rotavirus occur. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.
Estimation of Total Body Fat from Potassium-40 Content

International Nuclear Information System (INIS)

Taha Mohamed Taha Ahmed, T.M.T.

2010-01-01

This paper concerns on estimation of total body fat from potassium 40 content using total body counting technique. The work performed using fast scan whole body counter. Calibration of that system for K-40 was carried out under assumption that uniformity distribution of radioactivity of potassium was distributed in 10 polyethylene bottles phantom. Different body sizes were represented by 2, 4, 6, 8 and 10 polyethylene bottles; each bottle has a volume of 0.04 m3. The counting efficiency for each body size was determined. Lean body weight (LBW) was calculated for ten males and ten females using appropriate mathematical equation. Total Body Potassium, TBK for the same selected group was measured using whole body counter. A mathematical relationship between lean body weight and potassium content was deduced .Fat contents for some individuals were calculated and weight/height ratio was indicated for fatness.
Analysis of gold(I/III)-complexes by HPLC-ICP-MS demonstrates gold(III) stability in surface waters.

Science.gov (United States)

Ta, Christine; Reith, Frank; Brugger, Joël; Pring, Allan; Lenehan, Claire E

2014-05-20

Understanding the form in which gold is transported in surface- and groundwaters underpins our understanding of gold dispersion and (bio)geochemical cycling. Yet, to date, there are no direct techniques capable of identifying the oxidation state and complexation of gold in natural waters. We present a reversed phase ion-pairing HPLC-ICP-MS method for the separation and determination of aqueous gold(III)-chloro-hydroxyl, gold(III)-bromo-hydroxyl, gold(I)-thiosulfate, and gold(I)-cyanide complexes. Detection limits for the gold species range from 0.05 to 0.30 μg L(-1). The [Au(CN)2](-) gold cyanide complex was detected in five of six waters from tailings and adjacent monitoring bores of working gold mines. Contrary to thermodynamic predictions, evidence was obtained for the existence of Au(III)-complexes in circumneutral, hypersaline waters of a natural lake overlying a gold deposit in Western Australia. This first direct evidence for the existence and stability of Au(III)-complexes in natural surface waters suggests that Au(III)-complexes may be important for the transport and biogeochemical cycling of gold in surface environments. Overall, these results show that near-μg L(-1) enrichments of Au in environmental waters result from metastable ligands (e.g., CN(-)) as well as kinetically controlled redox processes leading to the stability of highly soluble Au(III)-complexes.
40 CFR 415.110 - Applicability; description of the potassium metal production subcategory.

Science.gov (United States)

2010-07-01

... potassium metal production subcategory. 415.110 Section 415.110 Protection of Environment ENVIRONMENTAL... SOURCE CATEGORY Potassium Metal Production Subcategory § 415.110 Applicability; description of the potassium metal production subcategory. The provisions of this subpart are applicable to discharges...

Crystal structure of the sodium-potassium pump

DEFF Research Database (Denmark)

Morth, J Preben; Pedersen, Bjørn Panyella; Toustrup-Jensen, Mads S

2007-01-01

The Na+,K+-ATPase generates electrochemical gradients for sodium and potassium that are vital to animal cells, exchanging three sodium ions for two potassium ions across the plasma membrane during each cycle of ATP hydrolysis. Here we present the X-ray crystal structure at 3.5 A resolution......-subunit is contained within a pocket between transmembrane helices and seems to be a novel regulatory element controlling sodium affinity, possibly influenced by the membrane potential. Udgivelsesdato: 2007-Dec-13...
Potassium permanganate ingestion as a suicide attempt

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Sebnem Eren Cevik

2012-02-01

Full Text Available Potassium permanganate is a highly corrosive, water-soluble oxidizing antiseptic. A 68- year-old female patient was admitted to our Emergency Department after ingestion of 3 tablets of 250 mg potassium permanganate as a suicide attempt. The physical exam revealed brown stained lesions in the oropharynx. Emergency endoscopy was performed by the gastroenterologist after the third hour of ingestion. Emergency endoscopy revealed multiple superficial (Grade I-II lesions on the esophagus and cardia, which were considered secondary to the caustic substance. The mainstay in the treatment of potassium permanganate is supportive and the immediate priority is to secure the airway. Emergency endoscopy is an important tool used to evaluate the location and severity of injury to the esophagus, stomach and duodenum after caustic ingestion. Patients with signs and symptoms of intentional ingestion should undergo endoscopy within 12 to 24 h to define the extent of the disease.
Potassium permanganate ingestion as a suicide attempt

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Tuba Cimilli Ozturk

2012-01-01

Full Text Available Potassium permanganate is a highly corrosive, water-soluble oxidizing antiseptic. A 68- year-old female patient was admitted to our Emergency Department after ingestion of 3 tablets of 250 mg potassium permanganate as a suicide attempt. The physical exam revealed brown stained lesions in the oropharynx. Emergency endoscopy was performed by the gastroenterologist after the third hour of ingestion. Emergency endoscopy revealed multiple superficial (Grade I-II lesions on the esophagus and cardia, which were considered secondary to the caustic substance. The mainstay in the treatment of potassium permanganate is supportive and the immediate priority is to secure the airway. Emergency endoscopy is an important tool used to evaluate the location and severity of injury to the esophagus, stomach and duodenum after caustic ingestion. Patients with signs and symptoms of intentional ingestion should undergo endoscopy within 12 to 24 h to define the extent of the disease.
Analysis on the Impact of the Fluctuation of the International Gold Prices on the Chinese Gold Stocks

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Jiankang Jin

2014-01-01

Full Text Available Five gold stocks in Chinese Shanghai and Shenzhen A-share and Comex gold futures are chosen to form the sample, for the purpose of analysing the impact of the fluctuation of the international gold prices on the gold stocks in Chinese Shanghai and Shenzhen A-share. Using the methods of unit root test, Granger causality test, VAR model, and impulse response function, this paper has analysed the relationship between the price change of the international gold futures and the price fluctuation of gold stocks in Chinese Shanghai and Shenzhen comprehensively. The results suggest the fluctuation of the international gold futures has a strong influence on the domestic futures.
Formation of gold nanorods and gold nanorod films for surface-enhanced Raman scattering spectroscopy

International Nuclear Information System (INIS)

Trotsyuk, L.L.; Kulakovich, O.S.; Shabunya-Klyachkovskaya, E.V.; Gaponenko, S.V.; Vashchenko, S.V.

2016-01-01

The formation of gold nanorods as well as thin films prepared via electrostatic deposition of gold nanorods has been investigated. The obtained gold nanorods films have been used as substrates for the surface-enhanced Raman scattering analysis of sulfur-free organic molecules mitoxantrone and malachite green as well as inorganic malachite microcrystals for the first time. The additional modification of films with L-cysteine allows one to significantly extend the use of gold nanorods for the surface-enhanced Raman scattering analysis. (authors)
Ketone deprotonation mediated by mono- and heterobimetallic alkali and alkaline earth metal amide bases: structural characterization of potassium, calcium, and mixed potassium-calcium enolates.

Science.gov (United States)

He, Xuyang; Noll, Bruce C; Beatty, Alicia; Mulvey, Robert E; Henderson, Kenneth W

2004-06-23

Potassium, calcium, and mixed potassium-calcium amide combinations have been shown to be efficient reagents in enolization reactions, and a set of representative intermediate mono- and heterobimetallic enolates have been successfully isolated and crystallographically characterized.
Metallic gold beads in hyaluronic acid

DEFF Research Database (Denmark)

Pedersen, Dan Sonne; Tran, Thao Phuong; Smidt, Kamille

2013-01-01

. In conclusion, our findings support that bio-liberation of gold from metallic gold surfaces have anti-inflammatory properties similar to classic gold compounds, warranting further studies into the pharmacological potential of this novel gold-treatment and the possible synergistic effects of hyaluronic acid....... by exploiting macrophage-induced liberation of gold ions (dissolucytosis) from gold surfaces. Injecting gold beads in hyaluronic acid (HA) as a vehicle into the cavities of the brain can delay clinical signs of disease progression in the MS model, experimental autoimmune encephalitis (EAE). This study...... investigates the anti-inflammatory properties of metallic gold/HA on the gene expression of tumor necrosis factor (Tnf-α), Interleukin (Il)-1β, Il-6, Il-10, Colony-stimulating factor (Csf)-v2, Metallothionein (Mt)-1/2, Bcl-2 associated X protein (Bax) and B cell lymphoma (Bcl)-2 in cultured J774 macrophages...
Potassium cycling and losses in grassland systems : a review

NARCIS (Netherlands)

Kayser, M; Isselstein, J

Cycling of potassium in grassland systems has received relatively little attention in research and practice in recent years. Balanced nutrient systems require consideration of nutrients other than nitrogen (N). Potassium (K) is needed in large amounts and is closely related to N nutrition. In
Determinants of renal potassium excretion in critically ill patients : The role of insulin therapy

NARCIS (Netherlands)

Hoekstra, Miriam; Yeh, Lu; Oude Lansink, Annemieke; Vogelzang, Mathijs; Stegeman, Coen A.; Rodgers, Michael G. G.; van der Horst, Iwan C. C.; Wietasch, Gotz; Zijlstra, Felix; Nijsten, Maarten W. N.

Objectives: Insulin administration lowers plasma potassium concentration by augmenting intracellular uptake of potassium. The effect of insulin administration on renal potassium excretion is unclear. Some studies suggest that insulin has an antikaliuretic effect although plasma potassium levels were
Data on electrical properties of nickel modified potassium polytitanates compacted powders.

Science.gov (United States)

Goffman, V G; Gorokhovsky, A V; Gorshkov, N V; Fedorov, F S; Tretychenko, E V; Sevrugin, A V

2015-09-01

Potassium polytitanates are new promising type of ferroelectric ceramic materials with high ionic conductivity, highly polarizable structure and extremely high permittivity. Its structure is formed by [TiO6] octahedral units to layers with mobile potassium and hydroxonium ions in-between. The treatment in solutions containing nickel ions allows forming heterostructured materials which consist of potassium polytitanate particles intercalated by Ni(2+) ions and/or decorated by nickel oxides NiO x . This modification route is fully dependant on solution pH, i.e. in acidic solutions the intercalation process prevails, in alkaline solutions potassium polytitanate is mostly decorated by the oxides. Therefore, electronic structure and electrical properties can be regulated depending on modification conditions, pH and ions concentration. Here we report the data on electric properties of potassium titanate modified in nickel sulfate solutions at different pH.
Data on electrical properties of nickel modified potassium polytitanates compacted powders

Directory of Open Access Journals (Sweden)

V.G. Goffman

2015-09-01

Full Text Available Potassium polytitanates are new promising type of ferroelectric ceramic materials with high ionic conductivity, highly polarizable structure and extremely high permittivity. Its structure is formed by [TiO6] octahedral units to layers with mobile potassium and hydroxonium ions in-between. The treatment in solutions containing nickel ions allows forming heterostructured materials which consist of potassium polytitanate particles intercalated by Ni2+ ions and/or decorated by nickel oxides NiOx. This modification route is fully dependant on solution pH, i.e. in acidic solutions the intercalation process prevails, in alkaline solutions potassium polytitanate is mostly decorated by the oxides. Therefore, electronic structure and electrical properties can be regulated depending on modification conditions, pH and ions concentration. Here we report the data on electric properties of potassium titanate modified in nickel sulfate solutions at different pH.
Potassium channels as drugs targets in therapy of cardiovascular diseases: 25 years later

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Protić Dragana

2013-03-01

Full Text Available Potassium channels are the most variable ion channel group. They participate in numerous cardiovascular functions, for example regulation of vascular tone, maintenance of resting cardiac membrane potential and excitability of cardiac conduction tissue. Both drugs and endogenous ligands could modulate potassium channel function, belonging to the potassium channel blockers or openers. Modulation of potassium channels could be a therapeutic or adverse drug action. Class III antiarrhythmic agents block the potassium channels, thereby prolonging repolarization phase of action potential with resulting prolongation of effective refractory period. Their effectiveness against supraventricular and ventricular arrhythmias should be weighted against their proarrhythmogenic potential. In addition, numerous other antiarrhythmic agents could modulate potassium channels as well. Diazoxide, minoxidil and nicorandil (well known arterial vasodilators, as well as numerous newly synthesized substances with still unknown therapeutic potential, belong to the potassium channel activators/openers. Therapeutic use of such vasodilators may involve treatment of hypertension (diazoxide, minoxidil and stable angina (nicorandil. Their use might be accompanied with side effects, such as vasodilation, edema, hypotension and reflex tachycardia. Potassium channel openers have also an important role in the treatment of peripheral vascular disease and pulmonary hypertension. In the future, drugs with selective effects on the vascular or cardiac potassium channels could be useful therapeutic agents.
POTASSIUM CHANNELS AS DRUGS TARGETS IN THERAPY OF CARDIOVASCULAR DESEASES: 25 YEARS LATER

Directory of Open Access Journals (Sweden)

Protić Dragana

2013-01-01

Full Text Available Potassium channels are the most variable ion channel group. They participate in numerous cardiovascular functions, for example regulation of vascular tone, maintenance of resting cardiac membrane potential and excitability of cardiac conduction tissue. Both drugs and endogenous ligands could modulate potassium channel function, belonging to the potassium channel blockers or openers. Modulation of potassium channels could be a therapeutic or adverse drug action. Class III antiarrhythmic agents block the potassium channels, thereby prolonging repolarization phase of action potential with resulting prolongation of effective refractory period. Their effectiveness against supraventricular and ventricular arrhythmias should be weighted against their proarrhythmogenic potential. In addition, numerous other antiarrhythmic agents could modulate potassium channels as well. Diazoxide, minoxidil and nicorandil (well known arterial vasodilators, as well as numerous newly synthesized substances with still unknown therapeutic potential, belong to the potassium channel activators/ openers. Therapeutic use of such vasodilators may involve treatment of hypertension (diazoxide, minoxidil and stable angina (nicorandil. Their use might be accompanied with side effects, such as vasodilation, edema, hypotension and reflex tachycardia. Potassium channel openers have also an important role in the treatment of peripheral vascular disease and pulmonary hypertension. In the future, drugs with selective effects on the vascular or cardiac potassium channels could be useful therapeutic agents.
Effects of potassium on kesterite solar cells: Similarities, differences and synergies with sodium

Directory of Open Access Journals (Sweden)

S. G. Haass

2018-01-01

Full Text Available Addition of alkali dopants is essential for achieving high-efficiency conversion efficiency of thin film solar cells based on chalcogenide semiconductors like Cu(In,GaSe2 (CIGS and Cu2ZnSn(S,Se4 (CZTSSe also called kesterite. Whereas the treatment with potassium allows boosting the performance of CIGS solar cells as compared to the conventional sodium doping, it is debated if similar effects can be expected for kesterite solar cells. Here the influence of potassium is investigated by introducing the dopant during the solution processing of kesterite absorbers. It is confirmed that the presence of potassium leads to an enhanced grain growth and a ten-fold lower potassium concentration is sufficient for obtaining grain size similar to sodium-containing absorbers. Potassium is located predominantly at grain boundaries and it suppresses incorporation of sodium into the absorber layer. The potassium doping increases the apparent carrier concentration to ∼2×1016 cm-3 for a potassium concentration of 0.2 at%. The potassium-doped solar cells yield conversion efficiency close to 10%, on par with only sodium-doped samples. Co-doping with potassium and sodium has not revealed any beneficial synergetic effects and it is concluded that both dopants exhibit similar effects on the kesterite solar cell performance.
Modeling removal of accumulated potassium from T-tubules by inward rectifier potassium channels

NARCIS (Netherlands)

Wallinga, W.; Vliek, M.; Wienk, E.D.; Alberink, M.J.; Ypey, D.L.; Ypey, D.L.

1996-01-01

The membrane models of Cannon et al. (1993) and Alberink et al. (1995) for mammalian skeletal muscle fibers are based upon Hodgkin-Huxley descriptions of sodium, potassium delayed rectifier and leak conductances and the capacitive current taking into account fast inactivation of sodium channels. Now
Inhibition of hydrolytic enzymes by gold compounds. I. beta-Glucuronidase and acid phosphatase by sodium tetrachloroaurate (III) and potassium tetrabromoaurate (III).

Science.gov (United States)

Lee, M T; Ahmed, T; Friedman, M E

1989-01-01

Purified bovine liver beta-glucuronidase (beta-D-glucuronide glucuronohydrolase, EC 3.2.1.32) and wheat germ acid phosphatase (orthophosphoric monoesterphosphohydrolase, EC 3.1.3.2) were inhibited with freshly dissolved and 24 h aquated tetrahaloaurate (III) compounds. Rate and equilibrium inhibition constants were measured. From this data two acid phosphatases species were observed. Equilibrium inhibition constants ranged from 1 to 12.5 microM for the various gold compounds toward both enzymes. The first order rate constants ranged between 0.005 and 0.04 min.-1 for most reactions with the exception of the fast reacting acid phosphatase which had values as high as 2.6 and 2.8 min.-1. It is observed that the beta-glucuronidase is rapidly inhibited during the equilibrium phase before the more slower reaction covalent bond formation takes place. The acid phosphatases form the covalent bonds more rapidly, especially the faster reacting species suggesting a unique difference in the active site geometry to that of the more slowly reacting species. The tightly bonded gold (III)-enzyme complex is probably the reason for its toxicity and non-anti-inflammatory use as a drug.
Deactivation of SCR catalysts by potassium: A study of potential alkali barrier materials

DEFF Research Database (Denmark)

Olsen, Brian Kjærgaard; Kügler, Frauke; Castellino, Francesco

2017-01-01

The use of coatings in order to protect vanadia based SCR catalysts against potassium poisoning has been studied by lab- and pilot-scale experiments. Three-layer pellets, consisting of a layer ofa potential coating material situated between layers of fresh and potassium poisoned SCR catalyst, were...... the coating process. Potassium had to some extent penetrated the MgO coat, and SEM analysis revealed it to be rather thick and fragile. Despite these observations, the coating did protect the SCR catalyst against potassium poisoning to some degree, leaving promise of further optimization....... used to test the ability of the barrier layer to block the diffusion of potassium across the pellet. Of MgO, sepiolite and Hollandite manganese oxide, MgO was the most effective potassium barrier, and no potassium was detected in the MgO layer upon exposure to SCR conditions for 7 days. Two monoliths...
Annual AFOSR Chemistry Program Review (19th)

Science.gov (United States)

1974-01-01

Chem., 42, 161 (1973). "A Rotating Ring Disk Electrode Study of the Adsorption of Lead on Gold in 0.5M Potassium Chloride," V. A. Vicente and S...Gold," D. F. Untereker and S. Bruckenstein, in preparation. "A Rotating Ring-Disk Study of the Adsorption of Thallium on Gold in 0.5H Potassium ... polyacrylic acid, and polydiallyl- phthalate. This paper will only cite the work on the photolysis of polydiallylphthalate. (PDAP). 70 The goal of this
A study on gold detection in Wenyu gold mine with XRF techniques

International Nuclear Information System (INIS)

Liu Liuchun

1988-01-01

A portable X ray fluorescence analyzer was used for detecting fluorcescent X rays from the elements associated with gold ores. Fe, As and Ni were chosen to be the indicator elements to analyse rock samples in Wenyu gold mine. Optimum indicators were determined, and it had proved to be successful to detect gold indirectly by measuring the yields of characteristic X rays of the elements. The method provided also valuable information on geology mapping and deposits forming environment
Coal gold agglomeration: an innovative approach to the recovery of gold in environmentally sensitive areas

Energy Technology Data Exchange (ETDEWEB)

Wall, N.C.; Hughes-Narborough, C.; Willey, G. [Davy (Stockton) Ltd., Stockton-on-Tees (United Kingdom)

1994-11-01

Coal Gold Agglomeration (CGA) was developed by BP Minerals and involves the selective recovery of oleophilic gold particles from an aqueous slurry into coal-oil agglomerates. These agglomerates are allowed to build up to a high gold loading and are then separated from the slurry. The loaded agglomerates are burned and the gold is finally recovered from the ash residue by dissolution and precipitation or by direct smelting. 6 figs.

Annealing relaxation of ultrasmall gold nanostructures

Science.gov (United States)

Chaban, Vitaly

2015-01-01

Except serving as an excellent gift on proper occasions, gold finds applications in life sciences, particularly in diagnostics and therapeutics. These applications were made possible by gold nanoparticles, which differ drastically from macroscopic gold. Versatile surface chemistry of gold nanoparticles allows coating with small molecules, polymers, biological recognition molecules. Theoretical investigation of nanoscale gold is not trivial, because of numerous metastable states in these systems. Unlike elsewhere, this work obtains equilibrium structures using annealing simulations within the recently introduced PM7-MD method. Geometries of the ultrasmall gold nanostructures with chalcogen coverage are described at finite temperature, for the first time.
Gold grade variation and particle microchemistry in exploration pits of the Batouri gold district, SE Cameroon

Science.gov (United States)

Vishiti, A.; Suh, C. E.; Lehmann, B.; Egbe, J. A.; Shemang, E. M.

2015-11-01

The Batouri area hosts lode-gold mineralization under several-m-thick lateritic cover. Pitting to bed rock on a geochemical Au anomaly defined from previous reconnaissance soil sampling identified five horizons ranging from saprock at the base to laterite at the top. Analysis of bulk samples from each horizon by fire assay shows that most of the horizons are barren although 119 ppb and 48 ppb Au values were obtained from one laterite horizon and one saprolite horizon, respectively, from two separate pits. All the horizons were panned and particulate gold was also recovered only from these two horizons. The gold grains from both horizons are morphologically and compositionally indistinguishable with rare quartz, pyrite and galena inclusions. The grains have irregular, sub-rounded, bean to elongated shapes and they show a remarkable core-rim zonation. Electron microprobe analysis of the grains recorded high gold content in the rims (86.3-100 wt%) and along fissures within the grains (95.1-100 wt%). The cores are relatively Ag rich (11.8-14 wt% Ag) while the rims (0.63-13.7 wt% Ag, most of the values fall within the lower limit of this range) and fissures (0.03-5.02 wt% Ag) are poor in Ag. The low Ag concentration in the rims and along fissures is attributed to preferential leaching of Ag; a process recognized in gold grains and platiniferous alloys from alluvia. The core composition of the grains is similar to that of primary gold composition in the bedrock. These results show that gold in the soil is relic particulate gold derived from the primary source with no evidence of secondary gold precipitation in the weathering cycle. In all the pits no horizon was systematically enriched in gold suggesting there has been no chemical remobilization of gold in this environment. Rather the dispersion of gold here is in the particulate form. Therefore combining particulate gold features with assay data is relevant to exploration in such tropical environments.
Composition effect of potassium-borate glasses on their relaxation properties

International Nuclear Information System (INIS)

Lomovskoj, V.A.; Bartenev, G.M.

1995-01-01

Relaxation processes in potassium-borate glasses have been investigated in detail for the first time. It is shown that low-temperature β-process of relaxation relating to rotational mobility of the B-O bond is the same for all potassium-borate glasses and B 2 O 3 . The process of β k -relaxation related to diffusion mobility of potassium ions depends on the composition of the glasses in the same way as α-relaxation (glass formation).12 refs., 10 figs., 2 tabs
Size fraction assaying of gold bearing rocks (for gold extraction) by instrumental neutron activation analysis

International Nuclear Information System (INIS)

Ahmed, K.; Dampare, S.B.; Addo, M.A.; Osae, S.; Adotey, D.K.; Adomako, D.

2005-01-01

A novel method has been developed for processing and extraction of gold from gold bearing rocks for use by small-scale gold miners in Ghana. The methodology involved crushing of gold bearing hard rocks to fine particles to form a composite sample and screening at a range of sizes. Gold distribution in the composite sample was determined as a function of particle size by using Instrumental Neutron Activation Analysis. The concentrations of gold for the corresponding particle sizes were 16.4 ± 0.17mg/kg for sizes <63μm; 161± 0.75 mg/kg for 63 - 125 μm, 0.53 + 0.03 mg/kg for 125 - 250 μm, 4.66± 0.07 mg/kg for 250 - 355 μm, 1.55 ± 0.06 for 355 - 425 μm, 0.80 ± 0.008 mg/kg for 425 -1000 μm, and 1.27 + 0.05 mg/kg for 1000-2000 μm. The average gold content in a 7.127 kg composite sample based on particle size found to be 3.08 mg/kg. (au)
Gold and uranium extraction

International Nuclear Information System (INIS)

James, G.S.; Davidson, R.J.

1977-01-01

A process for extracting gold and uranium from an ore containing them both comprising the steps of pulping the finely comminuted ore with a suitable cyanide solution at an alkaline pH, acidifying the pulp for uranium dissolution, adding carbon activated for gold recovery to the pulp at a suitable stage, separating the loaded activated carbon from the pulp, and recovering gold from the activated carbon and uranium from solution
Digoxin affects potassium homeostasis during exercise in patients with heart failure.

Science.gov (United States)

Schmidt, T A; Bundgaard, H; Olesen, H L; Secher, N H; Kjeldsen, K

1995-04-01

The aim was to evaluate whether digitalisation of heart failure patients affects extrarenal potassium handling during and following exercise, and to assess digoxin receptor occupancy in human skeletal muscle in vivo. In a paired study of before versus after digitalisation, 10 patients with congestive heart failure underwent identical exercise sessions consisting of three bouts of increasing work rates, 41-93 W, on a cycle ergometer. The final bouts were followed by exercise to exhaustion. The femoral vessels and brachial artery were catheterised. Arterial blood pressure, heart rate, leg blood flow, cardiac output, plasma potassium, haemoglobin, pH, and skeletal muscle receptor occupancy with digoxin in biopsies were determined. Occupancy of skeletal muscle Na/K-ATPase with digoxin was 9% (P digitalisation femoral venous plasma potassium increased by 0.2-0.3 mmol.litre-1 (P digitalisation the femoral venoarterial difference in plasma potassium increased by 50-100% (P digitalisation on plasma potassium were not the outcome of changes in haemodynamics, because cardiac output and leg blood flow increased by up to 13% and 19% (P < 0.05), nor was it the outcome of changes in haemoconcentration or pH. Extrarenal potassium handling is altered as a result of digoxin treatment. This is likely to reflect a reduced capacity of skeletal muscle Na/K-ATPase for active potassium uptake because of inhibition by digoxin, adding to the reduction of skeletal muscle Na/K-ATPase concentration induced by heart failure per se. In heart failure patients, improved haemodynamics induced by digoxin may, however, increase the capacity for physical conditioning. Thus the impairment of extrarenal potassium homeostasis by heart failure and digoxin treatment may be counterbalanced by training.
The conserved potassium channel filter can have distinct ion binding profiles: structural analysis of rubidium, cesium, and barium binding in NaK2K.

Science.gov (United States)

Lam, Yee Ling; Zeng, Weizhong; Sauer, David Bryant; Jiang, Youxing

2014-08-01

Potassium channels are highly selective for K(+) over the smaller Na(+). Intriguingly, they are permeable to larger monovalent cations such as Rb(+) and Cs(+) but are specifically blocked by the similarly sized Ba(2+). In this study, we used structural analysis to determine the binding profiles for these permeant and blocking ions in the selectivity filter of the potassium-selective NaK channel mutant NaK2K and also performed permeation experiments using single-channel recordings. Our data revealed that some ion binding properties of NaK2K are distinct from those of the canonical K(+) channels KcsA and MthK. Rb(+) bound at sites 1, 3, and 4 in NaK2K, as it does in KcsA. Cs(+), however, bound predominantly at sites 1 and 3 in NaK2K, whereas it binds at sites 1, 3, and 4 in KcsA. Moreover, Ba(2+) binding in NaK2K was distinct from that which has been observed in KcsA and MthK, even though all of these channels show similar Ba(2+) block. In the presence of K(+), Ba(2+) bound to the NaK2K channel at site 3 in conjunction with a K(+) at site 1; this led to a prolonged block of the channel (the external K(+)-dependent Ba(2+) lock-in state). In the absence of K(+), however, Ba(2+) acts as a permeating blocker. We found that, under these conditions, Ba(2+) bound at sites 1 or 0 as well as site 3, allowing it to enter the filter from the intracellular side and exit from the extracellular side. The difference in the Ba(2+) binding profile in the presence and absence of K(+) thus provides a structural explanation for the short and prolonged Ba(2+) block observed in NaK2K. © 2014 Lam et al.
Potassium iodide capsule treatment of feline sporotrichosis.

Science.gov (United States)

Reis, Erica G; Gremião, Isabella D F; Kitada, Amanda A B; Rocha, Raphael F D B; Castro, Verônica S P; Barros, Mônica B L; Menezes, Rodrigo C; Pereira, Sandro A; Schubach, Tânia M P

2012-06-01

Sporotrichosis is a mycosis caused by Sporothrix schenckii. The most affected animal is the cat; it has played an important role in the zoonotic transmission of this disease, especially in Rio de Janeiro, Brazil, since 1998. In order to evaluate the treatment of feline sporotrichosis with potassium iodide, an observational cohort was conducted in 48 cats with sporotrichosis at Instituto de Pesquisa Clínica Evandro Chagas, Fiocruz. All cats received potassium iodide capsules, 2.5 mg/kg to 20 mg/kg q24h. The cure rate was 47.9%, treatment failure was 37.5%, treatment abandonment was 10.4% and death was 4.2%. Clinical adverse effects were observed in 52.1% of the cases. Thirteen cats had a mild increase in hepatic transaminase levels during the treatment, six of them presented clinical signs suggestive of hepatotoxicity. Compared to previous studies with itraconazole and iodide in saturated solution, potassium iodide capsules are an alternative for feline sporotrichosis treatment.
An Assessment of Radiological Hazards from Gold Mine Tailings in the Province of Gauteng in South Africa

Science.gov (United States)

Kamunda, Caspah; Mathuthu, Manny; Madhuku, Morgan

2016-01-01

Radiological hazards associated with exposure to Naturally Occurring Radionuclides Materials from gold mine tailings in the province of Gauteng in South Africa were evaluated. A comparison was made with soil samples from a control area. In this study, gamma spectroscopy was used to measure the activity concentrations of these radionuclides in 56 soil samples from the mine tailings and 10 soil samples from the control area. The average activity concentrations in Bq∙kg−1 for Uranium-238, Thorium-232, and Potassium-40 from the mine tailings were found to be 785.3 ± 13.7, 43.9 ± 1.0 and 427.0 ± 13.1, respectively. On the other hand, the average activity concentrations in Bq∙kg−1 for Uranium-238, Thorium-232, and Potassium-40 from the control area were found to be 17.0.1 ± 0.4, 22.2 ± 0.5 and 496.8 ± 15.2, respectively. Radiological hazard parameters calculated from these activity concentrations were higher than recommended safe limits. In particular, calculated average values for the external hazard (Hex) and the internal hazard (Hin) from the mine tailings were found to be 2.4 and 4.5. Both these values were higher than unity, posing a significant health risk to the population in the area. PMID:26797624
Formation and structural characterization of potassium titanates and the potassium ion exchange property

International Nuclear Information System (INIS)

Wang Qiang; Guo Zhanhu; Chung, Jong Shik

2009-01-01

In the present work, K 2 Ti 2 O 5 , K 2 Ti 4 O 9 and K 2 Ti 6 O 13 are synthesized by solid state method. Their structures and morphologies are characterized by X-ray diffraction, Raman spectra and scanning electron microscopy. The binding energies of K, Ti and O in potassium titanates were then evaluated by X-ray photoelectron spectroscopy and compared with those in K/TiO 2 . Finally the corresponding K ion exchange properties are investigated by synthesizing NO oxidation catalysts with Co(NO 3 ) 2 precursor. It is found that the binding energy of K in K 2 Ti 2 O 5 is much higher than those in K 2 Ti 4 O 9 and K 2 Ti 6 O 13 , and because of which, it shows quite different catalytic performances. Compared with other potassium titanates, the K in K 2 Ti 2 O 5 is much easier to be exchanged out.
Suicide Attempt by Intravenous Potassium Self-Poisoning: A Case Report

Directory of Open Access Journals (Sweden)

Florent Battefort

2012-01-01

Full Text Available Introduction. Overdose of potassium is not as frequently encountered in clinical practice as hyperkalaemia due to acute or chronic renal disease. However, potassium overdoses leading to serious consequences do occur. Case Presentation. A 20-year-old nurse student presented with a cardiac arrest with asystole rhythm. Beside the patient were found four 50-mL syringes and empty vials of potassium chloride (20 mL, 10%. After initial resuscitation with epinephrine, 125 mL of a 4.2% intravenous solution of sodium bicarbonate were injected which resulted in the recovery of an effective cardiac activity. The patient recovered without sequelae. Conclusion. The difficulty in this case was to recognize the potassium poisoning. The advanced resuscitation with the use of a specific treatment helped to resuscitate the patient.
Free gold recovery by coal-oil agglomeration

Energy Technology Data Exchange (ETDEWEB)

Kotze, W.; Petersen, F.W. [Cape Technikon Cape Town (South Africa). Dept. of Chemical Engineering

2000-02-01

The gold mining industry has mainly relied upon the use of highly polluting chemicals, such as mercury and cyanide to recover gold from its ores. The Coal Gold Agglomeration (CGA) process was developed some years ago and has the advantage in that gold is recovered by a procedure which has little or no negative impact on the environment. A gold ore containing liberated gold particles is contacted with coal-oil agglomerates, whereby the gold is recovered into the coal/oil phase. Laboratory scale batch tests were performed on an artificial mixture gold slurry and gold recoveries of up to 85% were found under optimized conditions. By recycling the coal/oil phase, it was found that the gold loading onto the agglomerates was increased. Tests performed on an industrial ore yielded slightly lower gold recoveries, and X-ray Diffraction (XRD) analysis on the coal/oil phase showed that minerals other than gold were recovered into this phase. A comparative study was conducted whereby the CGA process was compared to mercury amalgamation. Gold recoveries obtained through amalgamation were 15% lower than by the agglomeration process, which indicates that this process can be considered favourably as an alternative to amalgamation. 16 refs., 2 figs., 6 tabs.
Spectroscopic diagnostic of gold plasma

Energy Technology Data Exchange (ETDEWEB)

Busquet, M.

1986-06-01

Results of a simulation of a gold-aluminium alloy target irradiated by laser are presented. FCI code has been used with a processing out of LTE of atomic physics of gold and of multigroup photonics. Emission and reabsorption of gold and aluminium lines are included.
Activation analysis in gold industry

International Nuclear Information System (INIS)

Kist, A. A.

2003-01-01

Nuclear techniques and methods were, are, and will be very important for many fields of science, agriculture, industry, etc. Among other examples one can remember role of the nuclear medicine (radiotherapy and radiodiagnostic methods) or semiconductors (communication, computing, information, etc.) which industrial production has been on initial stage based on activation analysis. One of very illustrative examples is application of nuclear methods in gold industry. This is given by favorable nuclear properties of gold. Uzbekistan is one of the main producers of gold. Open-cast mining and hydro metallurgic extraction (using leaching by cyanide and sorption by ion-exchange resin) is the mostly used technology. The typical gold ores are sulfide and contain elevated concentration of As and Sb. That needs special technology of gold extraction. Importance of gold for Uzbekistan economy is a reason why for many years there are carried out studies concerning to gold production. These studies include also nuclear methods and their results are successfully used in gold industry. The present paper gives a brief overview for period of 25 years. For many reasons most of these studies were not published before completely. Despite some results are obtained decades ago we decided to present the overview as an example how nuclear methods can cover requirements of the whole process. We are trying to sort these studies according to methods and applications
Direct electron transfer of horseradish peroxidase on Nafion-cysteine modified gold electrode

International Nuclear Information System (INIS)

Hong, Jun; Moosavi-Movahedi, Ali Akbar; Ghourchian, Hedayatollah; Rad, Ahmad Molaei; Rezaei-Zarchi, Saeed

2007-01-01

Direct electron transfer of horseradish peroxidase, immobilized on a functional membrane-modified gold electrode, was studied. The electrode showed a quasi-reversible electrochemical redox behavior with a formal potential of 60mV (versus Ag/AgCl) in 20mM potassium phosphate buffer solution at pH 7.0 and temperature 25 o C. The cathodic transfer coefficient was 0.42 and electron transfer rate constant was evaluated to be 1.6s -1 . Furthermore, the modified electrode was used as a biosensor and exhibited a satisfactory stability and sensitivity to H 2 O 2 . The linear range of this biosensor for H 2 O 2 determination was from 5.0x10 -6 to 1.5x10 -4 M while its detection limit, based on a signal-to-noise ratio of 3, was 1.3x10 -6 M. The apparent Michaelis-Menten constant (K m app ) for immobilized HRP was calculated to be 1.6x10 -4 M
Gamma-spectrometric correction in radiometric determination of potassium

International Nuclear Information System (INIS)

Gejsler, M.

1979-01-01

The method is described of determination of potassium in mixed fertilizers in production conditions on a chemical enterprise in the GDR. Potassium content was determined according to the value of measured radiation from potassium-40. For measurement probes were used with radiation counters. While changing raw material, coming to the enterprise has been established that in raw phosphate, supplied from Morocco, there is low enough concentration of the natural radioactive isotopes of the uranium-radium series. In this connection, the two-cannel gamma-spectroscopy method has been developed taking into account influence of the background from these isotopes. Principles are explained of the method used and descriptions are given of the instruments used and sources of errors are listed. Relative standard deviation of the potassiun determination by this method equals nearly to 5% [ru
Chrysotherapy: a synoptic review

Science.gov (United States)

Eisler, R.

2003-01-01

Chrysotherapy--the treatment of rheumatoid arthritis (RA) patients with monovalent gold drugs possessing anti-inflammatory and other properties--has been used with some success for more than 70 years; however, the metabolites generated from gold drugs have not been identified positively and the mechanisms of action are not known with certainty. This account selectively reviews recent available literature on the history of gold in medicine, with emphasis on RA; the role of Au+ and Au+ metabolites (Au(CN)2-, Au+3, Auo) and other mechanisms in chrysotherapy; current treatment regimes for RA using gold drugs; chrysotherapy case histories based on 2166 RA patients; and adverse effects of chrysotherapy, mainly various forms of dermatitis. More research seems needed on the role of gold metabolites in the treatment of RA, the use of more sensitive and uniform indicators of treatment success, improved routes of drug administration for maximum efficacy, and the development of gold drugs with minimal side effects.
Metamorphic Rock-Hosted Orogenic Gold Deposit Type as a Source of Langkowala Placer Gold, Bombana, Southeast Sulawesi

Directory of Open Access Journals (Sweden)

Arifudin Idrus

2014-06-01

Full Text Available DOI: 10.17014/ijog.v6i1.114In 2008, placer gold was discovered in Langkowala area (Bombana Regency, Southeast Sulawesi, Indonesia, and more than 60,000 traditional gold miners in the early 2009 have been operating by digging vertical pits and panning active stream sediments. The grade of placer gold ranges from 50 to 140 g/t. Local geological framework indicates that the placer gold is not related to volcanic rock-related hydrothermal gold deposit, e.g. epithermal, skarn or porphyry. This paper describes a preliminary study on possible primary deposit type as a source of the Langkowala (Bombana secondary placer gold. A field study indicates that the Langkowala (Bombana placer/paleoplacer gold is possibly related to gold-bearing quartz veins/veinlets hosted by metamorphic rocks particularly mica schist and metasediments in the area. These quartz veins/veinlets are currently recognized in metamorphic rocks at Wumbubangka Mountains, a northern flank of Rumbia Mountain Range. Sheared, segmented quartz veins/veinlets are of 2 cm to 2 m in width and contain gold in a grade varying between 2 and 61 g/t. At least, there are two generations of the quartz veins. The first generation of quartz vein is parallel to foliation of mica schist and metasediments with general orientation of N 300oE/60o; the second quartz vein generation crosscut the first quartz vein and the foliation of the wallrock. The first quartz veins are mostly sheared/deformed, brecciated, and occasionally sigmoidal, whereas the second quartz veins are relatively massive. The similar quartz veins/veinlets types are also probably present in Mendoke Mountain Range, in the northern side of Langkowala area. This primary gold deposit is called as ‘orogenic gold type’. The orogenic gold deposit could be a new target of gold exploration in Indonesia in the future.
A novel H(2)O(2) amperometric biosensor based on gold nanoparticles/self-doped polyaniline nanofibers.

Science.gov (United States)

Chen, Xiaojun; Chen, Zixuan; Zhu, Jinwei; Xu, Chenbin; Yan, Wei; Yao, Cheng

2011-10-01

A new kind of gold nanoparticles/self-doped polyaniline nanofibers (Au/SPAN) with grooves has been prepared for the immobilization of horseradish peroxidase (HRP) on the surface of glassy carbon electrode (GCE). The ratio of gold in the composite nanofibers was up to 64%, which could promote the conductivity and biocompatibility of SPAN and increase the immobilized amount of HRP molecules greatly. The electrode exhibits enhanced electrocatalytic activity in the reduction of H(2)O(2) in the presence of the mediator hydroquinone (HQ). The effects of concentration of HQ, solution pH and the working potential on the current response of the modified electrode toward H(2)O(2) were optimized to obtain the maximal sensitivity. The proposed biosensor exhibited a good linear response in the range from 10 to 2000 μM with a detection limit of 1.6 μM (S/N=3) under the optimum conditions. The response showed Michaelis-Menten behavior at larger H(2)O(2) concentrations, and the apparent Michaelis-Menten constant K(m) was estimated to be 2.21 mM. The detection of H(2)O(2) concentration in real sample showed acceptable accuracy with the traditional potassium permanganate titration. Copyright © 2011 Elsevier B.V. All rights reserved.
Medicinal gold compounds

International Nuclear Information System (INIS)

Parish, R.V.; Cottrill, S.M.

1987-01-01

A major use of gold compounds in the pharmaceutical industry is for anti-arthritic agents. The disease itself is not understood and little is known about the way in which the drugs act, but detailed pictures of the distribution of gold in the body are available, and some of the relevant biochemistry is beginning to emerge. The purpose of this article is to give a survey of the types of compounds presently employed in medicine, of the distribution of gold in the body which results from their use, and of some relevant chemistry. Emphasis is placed on results obtained in the last few years

Spectroscopic diagnostic of gold plasma

International Nuclear Information System (INIS)

Busquet, M.

1986-01-01

Results of a simulation of a gold-aluminium alloy target irradiated by laser are presented. FCI code has been used with a processing out of LTE of atomic physics of gold and of multigroup photonics. Emission and reabsorption of gold and aluminium lines are included [fr
Incorporation of surface plasmon resonance with novel valinomycin doped chitosan-graphene oxide thin film for sensing potassium ion

Science.gov (United States)

Zainudin, Afiq Azri; Fen, Yap Wing; Yusof, Nor Azah; Al-Rekabi, Sura Hmoud; Mahdi, Mohd Adzir; Omar, Nur Alia Sheh

2018-02-01

In this study, the combination of novel valinomycin doped chitosan-graphene oxide (C-GO-V) thin film and surface plasmon resonance (SPR) system for potassium ion (K+) detection has been developed. The novel C-GO-V thin film was deposited on the gold surface using spin coating technique. The system was used to monitor SPR signal for K+ in solution with and without C-GO-V thin film. The K+ can be detected by measuring the SPR signal when C-GO-V thin film is exposed to K+ in solution. The sensor produces a linear response for K+ ion up to 100 ppm with sensitivity and detection limit of 0.00948° ppm- 1 and 0.001 ppm, respectively. These results indicate that the C-GO-V film is high potential as a sensor element for K+ that has been proved by the SPR measurement.
Molecular dynamics simulation of polyacrylamides in potassium montmorillonite clay hydrates

Energy Technology Data Exchange (ETDEWEB)

Zhang Junfang [CSIRO Petroleum Resources, Ian Wark Laboratory, Bayview Avenue, Clayton, Victoria 3168 (Australia); Rivero, Mayela [CSIRO Petroleum, PO Box 1130, Bentley, Western Australia, 6102 (Australia); Choi, S K [CSIRO Petroleum Resources, Ian Wark Laboratory, Bayview Avenue, Clayton, Victoria 3168 (Australia)

2007-02-14

We present molecular dynamics simulation results for polyacrylamide in potassium montmorillonite clay-aqueous systems. Interlayer molecular structure and dynamics properties are investigated. The number density profile, radial distribution function, root-mean-square deviation (RMSD), mean-square displacement (MSD) and diffusion coefficient are reported. The calculations are conducted in constant NVT ensembles, at T = 300 K and with layer spacing of 40 A. Our simulation results showed that polyacrylamides had little impact on the structure of interlayer water. Density profiles and radial distribution function indicated that hydration shells were formed. In the presence of polyacrylamides more potassium counterions move close to the clay surface while water molecules move away, indicating that potassium counterions are hydrated to a lesser extent than the system in which no polyacrylamides were added. The diffusion coefficients for potassium and water decreased when polyacrylamides were added.
Corrosion mechanism of carbon brick in the blast furnace hearth by potassium

Science.gov (United States)

Jiao, Ke-xin; Zhang, Jian-liang; Liu, Zheng-jian; Liu, Zhuang-zhuang; Deng, Yong; Fan, Xiaoyue

2017-11-01

Alkali plays a significant role in the formation of brittle layer of carbon brick in the blast furnace hearth. The brittle layer in a commercial blast furnace hearth was investigated. Large amounts of potassium compounds were found in the brittle layer. Subsequently, the carbon bricks which reacted with potassium in the simulation of blast furnace hearth under different contents of potassium in the brick (0.25, 0.5, 1.0 and 2.0 wt.%) during various reaction times (0.5, 1, 2 and 4 h) were experimentally studied. Finally, the formation mechanism of the brittle layer in carbon brick was clarified. The investigation results show that a large number of cracks are present in the brittle layer. The average potassium content in the brittle layer is 1 wt.%. According to the experimental results, cracks in the carbon brick can be formed by the attack of potassium. The reason for the formation of the brittle layer in the carbon brick is that the liquid potassium permeates into the carbon brick through the pores and cracks, and then reacts with SiO2 and Al2O3 in CO atmosphere. The generated potassium compounds nepheline and leucite lead to the volume expansion and the damage of the carbon brick.
Spherical aggregates composed of gold nanoparticles

International Nuclear Information System (INIS)

Chen, C-C; Kuo, P-L; Cheng, Y-C

2009-01-01

Alkylated triethylenetetramine (C12E3) was synthesized and used as both a reductant in the preparation of gold nanoparticles by the reduction of HAuCl 4 and a stabilizer in the subsequent self-assembly of the gold nanoparticles. In acidic aqueous solution, spherical aggregates (with a diameter of about 202 ± 22 nm) of gold nanoparticles (with the mean diameter of ∼18.7 nm) were formed. The anion-induced ammonium adsorption of the alkylated amines on the gold nanoparticles was considered to provide the electrostatic repulsion and steric hindrance between the gold nanoparticles, which constituted the barrier that prevented the individual particles from coagulating. However, as the amino groups became deprotonated with increasing pH, the ammonium adsorption was weakened, and the amino groups were desorbed from the gold surface, resulting in discrete gold particles. The results indicate that the morphology of the reduced gold nanoparticles is controllable through pH-'tunable' aggregation under the mediation of the amino groups of alkylated amine to create spherical microstructures.
['Gold standard', not 'golden standard'

NARCIS (Netherlands)

Claassen, J.A.H.R.

2005-01-01

In medical literature, both 'gold standard' and 'golden standard' are employed to describe a reference test used for comparison with a novel method. The term 'gold standard' in its current sense in medical research was coined by Rudd in 1979, in reference to the monetary gold standard. In the same
Impact of potash fertilization on uptake of potassium by rice saplings

International Nuclear Information System (INIS)

Singh, V.N.; Sood, B.S.; Allawadhi, K.L.; Mittal, Raj

1995-01-01

Potash fertilization of plants that affects the potassium content of soils and its uptake by plants has been studied. For this rice saplings in pots were grown by planting Basmati seeds. Their growth was monitored by applying different amounts of potash fertilizers and keeping all other environment factors; soil, temperature, light and humidity etc. constant. Total potassium contents in rice saplings were determined using the method based upon XRF technique. The monitoring of growth of saplings of different pots shows that time duration of their freshness and greenishness and average length after fertilization were in increasing order with the amount of potassium fertilizer applied to the saplings. More over, the results of potassium content in different samples reveals that lower value of potash fertilizer has suppressed the potassium content in rice saplings as compared to those of saplings and soil of untreated pot. Potassium content of other saplings treated with 100, 150 and 200 mg of KCl per 200 ml of water were found to be enhanced from about 0.2 to 0.8 mg/g of dried amount with fertilizer contents. This shows that presently applied maximum amount of fertilizer is favourable for plants and visually induces no adverse effects in the saplings. (author). 5 refs., 2 tabs., 1 fig
41 CFR 101-45.002 - Gold.

Science.gov (United States)

2010-07-01

... 41 Public Contracts and Property Management 2 2010-07-01 2010-07-01 true Gold. 101-45.002 Section... PERSONAL PROPERTY § 101-45.002 Gold. (a) Gold will be sold in accordance with this section and part 102-38 of the Federal Management Regulation. (b) Sales of gold shall be processed to— (1) Use the sealed bid...
Interacting influence of potassium and polychlorinated biphenyl on cortisol and aldosterone biosynthesis

International Nuclear Information System (INIS)

Li, L.-A.; Lin, Tsu-Chun Emma

2007-01-01

Giving human adrenocortical H295R cells 14 mM KCl for 24 h significantly induced not only aldosterone biosynthesis but also cortisol biosynthesis. Pre-treating the cells with polychlorinated biphenyl 126 (PCB126) further increased potassium-induced aldosterone and cortisol productions in a dose-dependent manner, but all examined concentrations of PCB126 had little effect on the yields of precursor steroids progesterone and 17-OH-progesterone. Subsequent examinations revealed that CYP11B1 and CYP11B2 genes, responsible for the respective final steps of the cortisol and aldosterone biosynthetic pathways, exhibited increased responsiveness to PCB126 under high potassium. While 10 -5 M PCB126 was needed to induce a significant increase in the basal mRNA abundance of either gene, PCB126 could enhance potassium-induced mRNA expression of CYP11B1 at 10 -7 M and CYP11B2 at 10 -9 M. Actually, potassium and PCB126 synergistically upregulated mRNA expression of both genes. Potassium raised the transcriptional rates of CYP11B1 and CYP11B2 probably through a conserved Ad5 cis-element, whereas PCB126 appeared to regulate these two genes at the post-transcriptional level. Positive potassium-PCB126 synergism was also detected in CYP11B2 enzyme activity estimated by aldosterone/progesterone ratio. In contrast, potassium and PCB126 increased CYP11B1 enzyme activity or cortisol/17-OH-progesterone ratio additively. Moreover, potassium improved the time effect of PCB126 on gene expression and enzyme activity of CYP11B2, but not the PCB126 time response of CYP11B1. These data demonstrated that potassium differentially enhanced the potency of PCB126 to induce CYP11B1- and CYP11B2-mediated steroidogenesis
Potassium availability in soils - forms and spatial distribution

International Nuclear Information System (INIS)

Afari-Sefa, Victor; Kwakye, Peter K.; Nyamiah, Mercy; Okae-Anti, Daniel; Imoro, A. Ziblim

2004-10-01

Potassium forms the third most important plant nutrient limiting plant growth and consequently reducing crop yields. This study was conducted on soil potassium availability, distribution and relationship with other soil properties. Seventeen top soil samples (0-15 cm) were collected from four agro-ecological zones of the Central and Western Regions of Ghana. Water soluble, exchangeable and non-exchangeable forms of K were determined. The exchangeable K was extracted with 1 N-bar NH 4 OAc, 0.1 N-bar HNO 3 , 0.01 M-bar CaCl 2 , Bray No. 1 and 1 N-bar boiling HNO 3 . The non-exchangeable K was extracted with 1 N-bar boiling HNO 3 . Potassium was determined using flame photometer. The results showed that potassium is available in the soil in different forms and amounts. Soils from the forest-savanna transition and coastal savanna zones had relatively higher soil solution K concentration than soils from the moist rainforest and semi-deciduous forest zones. Also, soils of the semi-deciduous forest and forest savanna transition as well as the coastal savanna zones contained 2-3 times exchangeable K of the soils of the moist rainforest. The results also showed that the pH, texture as well as the land use affected K availability in the soils. (author)
Potassium vanadate K0.23V2O5 as anode materials for lithium-ion and potassium-ion batteries

Science.gov (United States)

Liu, Cailing; Luo, Shaohua; Huang, Hongbo; Wang, Zhiyuan; Wang, Qing; Zhang, Yahui; Liu, Yanguo; Zhai, Yuchun; Wang, Zhaowen

2018-06-01

A layered potassium vanadate K0.23V2O5 has been successfully prepared by the hydrothermal method and evaluated as an anode material for lithium-ion and potassium-ion batteries. High structural stability is demonstrated by the ex situ X-ray diffraction (XRD) and ex situ scanning electron microscopy (SEM). When used as an anode material for lithium-ion batteries, the K0.23V2O5 exhibits a reversible capacity of 480.4 mAh g-1 at 20 mA g-1 after 100 cycles and 439.7 mAh g-1 at 200 mA g-1 after 300 cycles as well as good cycling stability. Even at a high current density of 800 mA g-1, a high reversible capacity of 202.5 mAh g-1 can be retained, indicating excellent rate performance. Whereas in potassium-ion batteries, it retains a capacity of 121.6 mAh g-1 after 150 cycles at 20 mA g-1 and 97.6 mAh g-1 at 100 mA g-1 after 100 cycles. Such superior electrochemical performance of K0.23V2O5 can be ascribed to the special flower-like morphology and structure. Overall, the results highlight the great potential of K0.23V2O5 as an anode material for both lithium-ion and potassium-ion batteries.
Formulation and evaluation of sublingual tablets of losartan potassium

Directory of Open Access Journals (Sweden)

Nikunj J. Aghera

2012-05-01

Full Text Available Objective: Sublingual tablets of Losartan Potassium were prepared to improve its bioavailability, to avoid pre-systemic metabolism in the gastrointestinal tract and hepatic first pass elimination. Methods: The Sublingual tablets were prepared by direct compression procedure using different concentration of Starch 1500 and microcrystalline cellulose. Compatibility studies of drug and polymer were performed by FTIR spectroscopy and DSC. Preformulation property of API was evaluated. Postcompressional parameters such disintegration time, wetting time, water absorption ratio, in vitro drug release and in vivo bioavailability study of optimized formulation were determined. Results: FTIR spectroscopy and DSC study revealed that there was no possible interaction between drug and polymers. The precompression parameters were in acceptable range of pharmacopoeial specification. The disintegration time of optimized formulation (F3 was upto 48 sec. The in vitro release of Losartan Potassium was upto 15 min. The percentage relative bioavailability of Losartan Potassium from optimized sublingual tablets was found to be 144.7 %. Conclusions: Sublingual tablets of Losartan Potassium were successfully prepared with improved bioavailability.
Poly-thiosemicarbazide Membrane for Gold Adsorption and In-situ Growth of Gold Nanoparticles

KAUST Repository

Parra, Luis F.

2012-12-01

In this work the synergy between a polymer containing chelate sites and gold ions was explored by the fabrication of a polymeric membrane with embedded gold nanoparticles inside its matrix and by developing a process to recover gold from acidic solutions. After realizing that the thiosemicarbazide groups present in the monomeric unit of poly-thiosemicarbazide (PTSC) formed strong complexes with Au ions, membrane technology was used to exploit this property to its maximum. The incorporation of metal nanoparticles into polymeric matrices with current technologies involves either expensive and complicated procedures or leads to poor results in terms of agglomeration, loading, dispersion, stability or efficient use of raw materials. The fabrication procedure described in this thesis solves these problems by fabricating a PTSC membrane containing 33.5 wt% in the form of 2.9 nm gold nanoparticles (AuNPs) by a three step simple and scalable procedure. It showed outstanding results in all of the areas mentioned above and demonstrated catalytic activity for the reduction of 4-Nitrophenol (4−NP) to 4-Aminophenol (4−AP). The current exponential demand of gold for electronics has encouraged the development of efficient processes to recycle it. Several adsorbents used to recover gold from acidic solutions can be found in the literature with outstanding maximum uptakes,yet, poor kinetics leading to an overall inefficient process. The method developed in this dissertation consisted in permeating the gold-containing solution through a PTSC membrane that will capture all the Au ions by forming a metal complex with them. Forcing the ions through the pores of the membrane eliminates the diffusion limitations and the adsorption will only depended on the fast complexation kinetics, resulting in a very efficient process. A flux as high as 1868 L/h m2 was enough to capture >90% of the precious metal present in a solution of 100 ppm Au. The maximum uptake achieved without sacrificing
Expression, purification and functional reconstitution of slack sodium-activated potassium channels.

Science.gov (United States)

Yan, Yangyang; Yang, Youshan; Bian, Shumin; Sigworth, Fred J

2012-11-01

The slack (slo2.2) gene codes for a potassium-channel α-subunit of the 6TM voltage-gated channel family. Expression of slack results in Na(+)-activated potassium channel activity in various cell types. We describe the purification and reconstitution of Slack protein and show that the Slack α-subunit alone is sufficient for potassium channel activity activated by sodium ions as assayed in planar bilayer membranes and in membrane vesicles.
Gold mineralogy and extraction

International Nuclear Information System (INIS)

Cashion, J.D.; Brown, L.J.

1998-01-01

Several examples are examined in which Moessbauer spectroscopic analysis of gold mineral samples, treated concentrates and extracted species has provided information not obtainable by competing techniques. Descriptions are given of current work on bacterial oxidation of pyritic ores and on the adsorbed species from gold extracted from cyanide and chloride solutions onto activated carbon and polyurethane foams. The potential benefits for the gold mining industry from Moessbauer studies and some limitations on the use of the technique are also discussed
Gold mineralogy and extraction

Energy Technology Data Exchange (ETDEWEB)

Cashion, J.D.; Brown, L.J. [Monash University, Physics Department (Australia)

1998-12-15

Several examples are examined in which Moessbauer spectroscopic analysis of gold mineral samples, treated concentrates and extracted species has provided information not obtainable by competing techniques. Descriptions are given of current work on bacterial oxidation of pyritic ores and on the adsorbed species from gold extracted from cyanide and chloride solutions onto activated carbon and polyurethane foams. The potential benefits for the gold mining industry from Moessbauer studies and some limitations on the use of the technique are also discussed.
Metamorphic Rock-Hosted Orogenic Gold Deposit Type as a Source of Langkowala Placer Gold, Bombana, Southeast Sulawesi

OpenAIRE

Idrus, Arifudin; Nur, I; Warmada, I. W; Fadlin, Fadlin

2011-01-01

DOI: 10.17014/ijog.v6i1.114In 2008, placer gold was discovered in Langkowala area (Bombana Regency), Southeast Sulawesi, Indonesia, and more than 60,000 traditional gold miners in the early 2009 have been operating by digging vertical pits and panning active stream sediments. The grade of placer gold ranges from 50 to 140 g/t. Local geological framework indicates that the placer gold is not related to volcanic rock-related hydrothermal gold deposit, e.g. epithermal, skarn or porphyry. This pa...
Mechanism of cesium sorption on potassium titanium hexacyanoferrate

International Nuclear Information System (INIS)

Sun Yongxia; Xu Shiping; Song Chongli

1998-01-01

The mechanism of cesium sorption on potassium titanium hexacyanoferrate is described. The dependence of the sorption speed on temperature, particle granule size, and the stirring speed is studied. The results show that the sorption process is controlled by liquid film diffusion and particle diffusion. An exchange reaction occurs mainly between K + in the exchanger and Cs + in the solution, i.e. potassium titanium hexacyanoferrate, and Cs + of simulated high-level liquid waste
Sodium-to-Potassium Ratio and Blood Pressure, Hypertension, and Related Factors12

Science.gov (United States)

Perez, Vanessa; Chang, Ellen T.

2014-01-01

The potential cost-effectiveness and feasibility of dietary interventions aimed at reducing hypertension risk are of considerable interest and significance in public health. In particular, the effectiveness of restricted sodium or increased potassium intake on mitigating hypertension risk has been demonstrated in clinical and observational research. The role that modified sodium or potassium intake plays in influencing the renin-angiotensin system, arterial stiffness, and endothelial dysfunction remains of interest in current research. Up to the present date, no known systematic review has examined whether the sodium-to-potassium ratio or either sodium or potassium alone is more strongly associated with blood pressure and related factors, including the renin-angiotensin system, arterial stiffness, the augmentation index, and endothelial dysfunction, in humans. This article presents a systematic review and synthesis of the randomized controlled trials and observational research related to this issue. The main findings show that, among the randomized controlled trials reviewed, the sodium-to-potassium ratio appears to be more strongly associated with blood pressure outcomes than either sodium or potassium alone in hypertensive adult populations. Recent data from the observational studies reviewed provide additional support for the sodium-to-potassium ratio as a superior metric to either sodium or potassium alone in the evaluation of blood pressure outcomes and incident hypertension. It remains unclear whether this is true in normotensive populations and in children and for related outcomes including the renin-angiotensin system, arterial stiffness, the augmentation index, and endothelial dysfunction. Future study in these populations is warranted. PMID:25398734
Exploration for gold mineralization in the Arabo Nubian Shield: Using remote sensing Approach

Science.gov (United States)

Ramadan, Talaat

2013-04-01

In the southern part of the Eastern Desert of Egypt, Landsat Thematic Mapper (ETM+) data and fieldwork was combined with mineralogical and geochemical investigations in order to detect and characterize alteration zones within Pan-African rocks. The processing of Landsat ETM+ data using ratioing (bands 5/7,5/1,4/3 in Red, Green, Blue) showed two different types of alteration zones (type l and 2). Type 1 is close to the ophiolitic ultramafic rocks and type 2 is located within island-arc related metavolcanic rocks at the study areas. Both of these alteration zones are concordant with the main NW-SE structural trend. Mineralogical studies indicate that the alteration zones of type 1 consist mainly of calcite, ankerite, magnesite, dolomite and quartz. Chromian spinel, pyrite, and Ni-bearing sulphides (gersdorffite, pentlandite and polydymite) are the main ore minerals within this zone. Alteration zones of type 2 are strongly potassium-enriched and pyrophyllite, kaolinite, illite, gypsum and quartz occur. The brecciated quartz-veins associated with theses alteration zones consist of quartz, Fe-hydroxides, hematite and native gold. The gold content reaches up to 5 g/t in the alteration zone, while it extends up to 50 g/t in the quartz veins. This study presents a mineralogical characterization of such zones and demonstrates the utility of orbital remote sensing for finding unknown alteration zones in the Eastern Desert and other arid areas with similar host rock lithologies.

A novel potassium channel in photosynthetic cyanobacteria.

Directory of Open Access Journals (Sweden)

Manuela Zanetti

Full Text Available Elucidation of the structure-function relationship of a small number of prokaryotic ion channels characterized so far greatly contributed to our knowledge on basic mechanisms of ion conduction. We identified a new potassium channel (SynK in the genome of the cyanobacterium Synechocystis sp. PCC6803, a photosynthetic model organism. SynK, when expressed in a K(+-uptake-system deficient E. coli strain, was able to recover growth of these organisms. The protein functions as a potassium selective ion channel when expressed in Chinese hamster ovary cells. The location of SynK in cyanobacteria in both thylakoid and plasmamembranes was revealed by immunogold electron microscopy and Western blotting of isolated membrane fractions. SynK seems to be conserved during evolution, giving rise to a TPK (two-pore K(+ channel family member which is shown here to be located in the thylakoid membrane of Arabidopsis. Our work characterizes a novel cyanobacterial potassium channel and indicates the molecular nature of the first higher plant thylakoid cation channel, opening the way to functional studies.
Cesium immobilization into potassium magnesium phosphate matrix

International Nuclear Information System (INIS)

Sayenko, S.Y.; Shkuropatenko, V.A.; Bereznyak, O.P.; Hodyreva, Y.S.; Tarasov, R.V.; Virych, V.D.; Ulybkina, E.A.; Pylypenko, O.V.; Kholomeev, G.O.; Zykova, A.V.; Wagh, Arun S.

2017-01-01

The possibility of isomorphous substitution of potassium ions by cesium ions in the structure of potassium magnesium phosphate KMgPO 4 centred dot 6H 2 O (PMP) was shown. It was established, that the Cs included into the PMP matrix does not transfer to the environment during high temperatures heating process (1176 deg C, 3 hours). Analysis of the IR absorption spectrum of the PMP sample has demonstrated that an increase in the amount of additive of the cesium chloride resulted in the shift of the main bands in the spectrum to the low-frequency region with average shift value 10 cm -1 , which indicates the strengthening of bonds in the crystal lattice of matter. The calculated degree of substitution of potassium by cesium during energy release process in the PMP matrix at the level of vitrified high level wastes is about 4%, i. e. the PMP matrix should correspond to the formula K 0.96 Cs 0.04 MgPO 4 centred dot 6H 2 O.
The relation of potassium and sodium intakes to diet cost among U.S. adults.

Science.gov (United States)

Drewnowski, A; Rehm, C D; Maillot, M; Monsivais, P

2015-01-01

The 2010 Dietary Guidelines recommended that Americans increase potassium and decrease sodium intakes to reduce the burden of hypertension. One reason why so few Americans meet the recommended potassium or sodium goals may be perceived or actual food costs. This study explored the monetary costs associated with potassium and sodium intakes using national food prices and a representative sample of US adults. Dietary intake data from the 2001-2002 National Health and Nutrition Examination Survey were merged with a national food prices database. In a population of 4744 adults, the association between the energy-adjusted sodium and potassium intakes, and the sodium-to-potassium ratio (Na:K) and energy-adjusted diet cost was evaluated. Diets that were more potassium-rich or had lower Na:K ratios were associated with higher diet costs, while sodium intakes were not related to cost. The difference in diet cost between extreme quintiles of potassium intakes was $1.49 (95% confidence interval: 1.29, 1.69). A food-level analysis showed that beans, potatoes, coffee, milk, bananas, citrus juices and carrots are frequently consumed and low-cost sources of potassium. Based on existing dietary data and current American eating habits, a potassium-dense diet was associated with higher diet costs, while sodium was not. Price interventions may be an effective approach to improve potassium intakes and reduce the Na:K ratio of the diet. The present methods helped identify some alternative low-cost foods that were effective in increasing potassium intakes. The identification and promotion of lower-cost foods to help individuals meet targeted dietary recommendations could accompany future dietary guidelines.
The influence of monovalent cations on trimeric G protein Gi1alfa activity in HEK293 cells stably expressing DOR-Gi1alfa (Cys351-Ile351) fusion protein

Czech Academy of Sciences Publication Activity Database

Vošahlíková, Miroslava; Svoboda, Petr

2011-01-01

Roč. 60, č. 3 (2011), s. 541-547 ISSN 0862-8408 R&D Projects: GA AV ČR(CZ) IAA500110606; GA MŠk(CZ) LC554; GA ČR(CZ) GD305/08/H037 Institutional research plan: CEZ:AV0Z50110509 Keywords : delta-opioid receptor (DOR) * monovalent ions * G(i)1alfa protein Subject RIV: CE - Biochemistry Impact factor: 1.555, year: 2011
Nanotoxicity of gold and gold-cobalt nanoalloy.

Science.gov (United States)

Girgis, E; Khalil, W K B; Emam, A N; Mohamed, M B; Rao, K V

2012-05-21

Nanotoxicology test of gold nanoparticles (Au NPs) and gold-cobalt (Au-Co) nanoalloy is an important step in their safety evaluation for biomedical applications. The Au and Au-Co NPs were prepared by reducing the metal ions using sodium borohydride (NaBH(4)) in the presence of polyvinyl pyrrolidone (PVP) as a capping material. The average size and shape of the nanoparticles (NPs) were characterized using high resolution transmission electron microscopy (HRTEM). Cobalt presence in the nanoalloy was confirmed by energy dispersive X-ray spectroscopy (EDX) analysis, and the magnetic properties of these particles were determined using a vibrating sample magnetometer (VSM). The Gold and gold-cobalt NPs of average size 15 ± 1.5 nm were administered orally to mice with a dose of 80, 160, and 320 mg/kg per body weight (bw) using gavages. Samples were collected after 7 and 14 days of the treatment. The results indicated that the Au-Co NPs were able to induce significant alteration in the tumor-initiating genes associated with an increase of micronuclei (MNs) formation and generation of DNA adduct (8-hydroxy-2-deoxyguanosine, 8-OHdG) as well as a reduction in the glutathione peroxidase activity. This action of Au-Co NPs was observed using 160 and 320 mg/kg bw at both time intervals. However, Au NPs had much lower effects than Au-Co NPs on alteration in the tumor-initiating genes, frequency of MNs, and generation of 8-OHdG as well as glutathione peroxidase activity except with the highest dose of Au NPs. This study suggests that the potential to cause in vivo genetic and antioxidant enzyme alterations due to the treatment by Au-Co nanoalloy may be attributed to the increase in oxidative stress in mice.
Dietary Impact of Adding Potassium Chloride to Foods as a Sodium Reduction Technique

Directory of Open Access Journals (Sweden)

Leo van Buren

2016-04-01

Full Text Available Potassium chloride is a leading reformulation technology for reducing sodium in food products. As, globally, sodium intake exceeds guidelines, this technology is beneficial; however, its potential impact on potassium intake is unknown. Therefore, a modeling study was conducted using Dutch National Food Survey data to examine the dietary impact of reformulation (n = 2106. Product-specific sodium criteria, to enable a maximum daily sodium chloride intake of 5 grams/day, were applied to all foods consumed in the survey. The impact of replacing 20%, 50% and 100% of sodium chloride from each product with potassium chloride was modeled. At baseline median, potassium intake was 3334 mg/day. An increase in the median intake of potassium of 453 mg/day was seen when a 20% replacement was applied, 674 mg/day with a 50% replacement scenario and 733 mg/day with a 100% replacement scenario. Reformulation had the largest impact on: bread, processed fruit and vegetables, snacks and processed meat. Replacement of sodium chloride by potassium chloride, particularly in key contributing product groups, would result in better compliance to potassium intake guidelines (3510 mg/day. Moreover, it could be considered safe for the general adult population, as intake remains compliant with EFSA guidelines. Based on current modeling potassium chloride presents as a valuable, safe replacer for sodium chloride in food products.
In harmony with gold and uranium

International Nuclear Information System (INIS)

Anon.

1983-01-01

A profile is given on Mr Clive Knobbs as managing director of Harmony gold mine. From March 1 1983 he succeeded as deputy chairman of the group's gold and uranium division, and became the Rand Mines representative on the Gold Producers Committee and the Executive Committee of the Chamber of Mines. The article also takes a look at gold and uranium mining in general
The extractive metallurgy of gold

Science.gov (United States)

Kongolo, K.; Mwema, M. D.

1998-12-01

Mössbauer spectroscopy has been successfully used in investigation of the gold compounds present in ores and the gold species which occur during the process metallurgy of this metal. This paper is a survey of the basic recovery methods and techniques used in extractive metallurgy of gold. Process fundamentals on mineral processing, ore leaching, zinc dust cementation, adsorption on activated carbon, electrowinning and refining are examined. The recovery of gold as a by-product of the copper industry is also described. Alternative processing methods are indicated in order to shed light on new interesting research topics where Mössbauer spectroscopy could be applied.
The extractive metallurgy of gold

International Nuclear Information System (INIS)

Kongolo, K.; Mwema, M.D.

1998-01-01

Moessbauer spectroscopy has been successfully used in investigation of the gold compounds present in ores and the gold species which occur during the process metallurgy of this metal. This paper is a survey of the basic recovery methods and techniques used in extractive metallurgy of gold. Process fundamentals on mineral processing, ore leaching, zinc dust cementation, adsorption on activated carbon, electrowinning and refining are examined. The recovery of gold as a by-product of the copper industry is also described. Alternative processing methods are indicated in order to shed light on new interesting research topics where Moessbauer spectroscopy could be applied
The extractive metallurgy of gold

Energy Technology Data Exchange (ETDEWEB)

Kongolo, K.; Mwema, M.D. [University of Lubumbashi, Zaire, Gecamines Metallurgical Research Centre, Likasi, Zaire, c/o Gecamines Brussels (Belgium)

1998-12-15

Moessbauer spectroscopy has been successfully used in investigation of the gold compounds present in ores and the gold species which occur during the process metallurgy of this metal. This paper is a survey of the basic recovery methods and techniques used in extractive metallurgy of gold. Process fundamentals on mineral processing, ore leaching, zinc dust cementation, adsorption on activated carbon, electrowinning and refining are examined. The recovery of gold as a by-product of the copper industry is also described. Alternative processing methods are indicated in order to shed light on new interesting research topics where Moessbauer spectroscopy could be applied.
Recovery of carrier-free gold-195

International Nuclear Information System (INIS)

Iofa, B.Z.; Ivanova, N.A.

1995-01-01

It is known that gold(III) is readily extracted from nitric acid solutions with ethers. The authors have studied extraction of trace amounts of gold(III) from nitric acid solutions with diethyl and diisopropyl ethers in the presence of significant excess of Pt(IV). Distribution coefficients of gold(III) were measured radiometrically using carrier-free gold-195 or spectrophotometrically in the presence of platinum(IV). Very high coefficients of gold separation from platinum may be achieved. Preliminary experiments have shown that zinc-65 was not extracted with ethers from nitric acid solutions. As an extraction system, the authors have chosen the system 10 M HNO 3 -diisopropyl ether. After model experiments, the authors have performed recovery of carrier-free gold-195 from a real platinum target irradiated with protons in a cyclotron
Modelling of Radiological Health Risks from Gold Mine Tailings in Wonderfonteinspruit Catchment Area, South Africa

Directory of Open Access Journals (Sweden)

Manny Mathuthu

2016-06-01

Full Text Available Mining is one of the major causes of elevation of naturally-occurring radionuclide material (NORM concentrations on the Earth’s surface. The aim of this study was to evaluate the human risk associated with exposure to NORMs in soils from mine tailings around a gold mine. A broad-energy germanium detector was used to measure activity concentrations of these NORMs in 66 soil samples (56 from five mine tailings and 10 from the control area. The RESidual RADioactivity (RESRAD OFFSITE modeling program (version 3.1 was then used to estimate the radiation doses and the cancer morbidity risk of uranium-238 (238U, thorium-232 (232Th, and potassium-40 (40K for a hypothetical resident scenario. According to RESRAD prediction, the maximum total effective dose equivalent (TEDE during 100 years was found to be 0.0315 mSv/year at year 30, while the maximum total excess cancer morbidity risk for all the pathways was 3.04 × 10−5 at year 15. The US Environmental Protection Agency considers acceptable for regulatory purposes a cancer risk in the range of 10−6 to 10−4. Therefore, results obtained from RESRAD OFFSITE code has shown that the health risk from gold mine tailings is within acceptable levels according to international standards.
Development Of Silica Potassium Fertilizers From Trass Rock With Calcination Process

Science.gov (United States)

Wahyusi, KN; Siswanto

2018-01-01

Rocks and sand mines have important benefits for life. With the many benefits of rocks, it is a pity if Indonesia has a lot of raw material reserves waste it. Examples of the benefits of rocks that can be converted into silica potassium fertilizer by reacting with potassium hydroxide. Examples of rocks that can be taken trass rock. The procedure for making silica potassium is by reacting 100 mesh trass rock with KOH and K2CO3 reagents whose composition is arranged by weight ratio, where the base of the trass rock is 100 gr. The process is carried out at a temperature of 1.250 °C with a reaction time of 1 hour. The results obtained are the best silica potassium fertilizer for K2CO3 reagent which is 500gr: 74gr with SiO2 content: 26.8% and K2O content: 27.3%, with water solubility 24.02%, while for silica potassium fertilizer product from The best trass rock for KOH reagent is with a mol ratio of 400 gr : 60 gr with SiO2 content : 23.6% and K2O content: 22.2%, with 25.65% water solubility. The pore size of silica potassium fertilizer product of this trass rock, the range 350 - 1000 nm.
Estimation of potassium concentration in coconut water by beta radioactivity measurement

International Nuclear Information System (INIS)

Reddy, P.J.; Narayani, K.; Bhade, S.P.D.; Anilkumar, S.; Kolekar, R.V.; Singh, Rajvir; Pradeepkumar, K.S.

2014-01-01

Potassium is widely distributed in soil, in all vegetable, fruits and animal tissues. Approximately half the radioactivity found in humans comes from 40 K. Potassium is an essential element in our diet since it is required for proper nerve and muscle function, as well as for maintaining the fluid balance of cells and heart rhythm. Potassium can enter the body mainly consuming fruits, vegetables and food. Tender coconut water is consumed widely as natural refreshing drink which is rich in potassium. The simple way to determine 40 K activity is by gamma ray spectrometry. However, the low abundance of this gamma photon makes the technique less sensitive compared to gross beta measurement. Many analytical methods are reported for potassium estimation which is time consuming and destructive in nature. A unique way to estimate 40 K by beta activity is by Cerenkov Counting technique using Liquid Scintillation Analyzer. Also much lower detection limit is achieved, allowing for greater precision. In this work, we have compared two methods to arrive at the potassium concentration in tender and matured coconut water by measuring 40 K. One is non-scintillator method based on measurement of the Cerenkov radiation generated from the high-energy β of 40 K. The second method is based on beta activity measurement using low background Gas flow counter
Gold--a controversial sensitizer

DEFF Research Database (Denmark)

Bruze, M; Andersen, Klaus Ejner

1999-01-01

allergy to gold sodium thiosulfate were published at the beginning of the 1990s, the allergic nature of the reported positive patch test reactions to gold was questioned. The major argument for such questioning was the lack of demonstrable clinical relevance in most positive reactors. A major reason......Until recently, gold allergy was considered to be extremely rare. Gold has been used and worshipped for thousands of years without any obvious complaints of skin problems, either in those participating in mining and other ways of prospecting, or in those wearing jewellery. When studies on contact...... for the questioning may have been confusion in differentiating between contact allergy and allergic contact dermatitis. To arrive at a diagnosis of allergic contact dermatitis, 3 steps have, in principle, to be fulfilled: (i) establishment of contact allergy; (ii) demonstration of present exposure; (iii) assessment...
Effects of water soaking and/or sodium polystyrene sulfonate addition on potassium content of foods.

Science.gov (United States)

Picq, Christian; Asplanato, Marion; Bernillon, Noémie; Fabre, Claudie; Roubeix, Mathilde; Ricort, Jean-Marc

2014-09-01

In this study, we determined, by atomic absorption spectrophotometry, the potassium amount leached by soaking or boiling foods identified by children suffering from chronic renal failure as "pleasure food" and that they cannot eat because of their low-potassium diet, and evaluated whether addition of sodium polystyrene sulfonate resin (i.e. Kayexalate®) during soaking or boiling modulated potassium loss. A significant amount of potassium content was removed by soaking (16% for chocolate and potato, 26% for apple, 37% for tomato and 41% for banana) or boiling in a large amount of water (73% for potato). Although Kayexalate® efficiently dose-dependently removed potassium from drinks (by 48% to 73%), resin addition during soaking or boiling did not eliminate more potassium from solid foods. Our results therefore provide useful information for dietitians who elaborate menus for people on potassium-restricted diets and would give an interesting alternative to the systematic elimination of all potassium-rich foods from their diet.
Ionic double layer of atomically flat gold formed on mica templates

International Nuclear Information System (INIS)

Chilcott, Terry C.; Wong, Elicia L.S.; Coster, Hans G.L.; Coster, Adelle C.F.; James, Michael

2009-01-01

Electrical impedance spectroscopy characterisations of gold surfaces formed on mica templates in contact with potassium chloride electrolytes were performed at the electric potential of zero charge over a frequency range of 6 x 10 -3 to 100 x 10 3 Hz. They revealed constant-phase-angle (CPA) behaviour with a frequency exponent value of 0.96 for surfaces that were also characterised as atomically flat using atomic force microscopy (AFM). As the frequency exponent value was only marginally less than unity, the CPA behaviour yielded a realistic estimate for the capacitance of the ionic double layer. The retention of the CPA behaviour was attributed to specific adsorption of chloride ions which was detected as an adsorption conductance element in parallel with the CPA impedance element. Significant variations in the ionic double layer capacitance as well as the adsorption conductance were observed for electrolyte concentrations ranging from 33 μM to 100 mM, but neither of these variations correlated with concentration. This is consistent with the electrical properties of the interface deriving principally from the inner or Stern region of the double layer.
Influence of Herbal Complexes Containing Licorice on Potassium Levels: A Retrospective Study

Directory of Open Access Journals (Sweden)

WooSang Jung

2014-01-01

Full Text Available To observe the influence of these complexes on potassium levels in a clinical setting, we investigated the influence of herbal complexes containing licorice on potassium levels. We retrospectively examined the medical records of patients treated with herbal complexes containing licorice from January 1, 2010, to December 31, 2010. We recorded the changes in the levels of potassium, creatinine, and blood urea nitrogen and examined the differences between before and after herbal complexes intake using a paired t-test. In addition, we investigated the prevalence of hypokalemia among these patients and reviewed such patients. We identified 360 patients who did not show significant changes in the levels of potassium and creatinine (P=0.815, 0.289. We observed hypokalemia in 6 patients. However, in 5 patients, the hypokalemia did not appear to be related to the licorice. Thus, we could suggest that herbal complexes containing licorice do not significantly influence the potassium levels in routine clinical herbal therapies. However, we propose that follow-up examination for potassium levels is required to prevent any unpredictable side effects of administration of licorice in routine herbal medicine care.
Contribution to the liquid-vapour equilibrium of potassium and sodium mixtures

International Nuclear Information System (INIS)

Schreinlechner, I.; Schwarz, N.

1975-10-01

In this paper the phase diagram of the binary system potassium-sodium in the liquid-vapour range was calculated for different pressures and temperatures, assuming the two metals acting as ideal solution. The assumption was verified by experimental results. It is thus possible to calculate the separation factor for the rectification of potassium and to estimate the content of sodium in the vapour phase during experiments with vapourized potassium from the data of the vapour pressures of the pure metals. (author)
Translocation kinetics of 14C-photosynthate in hybrid rice grown at different potassium levels

International Nuclear Information System (INIS)

Jiang Dean; Shen Yuwei; Xie Xuemin; Rao Lihua; Lu Qing

1993-01-01

The kinetics of translocation of 14 C-assimilate in hybrid rice plant was studied with 14 CO 2 fed to functional leaf at the tillering and filling stages. The result indicated that the relationship between percentage (V) of photosynthate exporting out of the source leaf or that of assimilate into sink, expanding young leaf or filling panicle, respectively,and time(t)after introducing 14 CO 2 into the leaf was extremely coincided with the regression equation : v = V (t + k)/K m + (t + k). At the tillering stage, fully extended top leaf could export 66% ∼ 79% of its photosynthate assimilated at different potassium levels, and both export potential and rate of 14 C-photosynthate in the fed leaf decreased under the low potassium (1 ppm K supplied), but the rate obviously increased in the superfluous potassium (80 ppm K supplied) in spite of slightly low exporting capacity. Main sink, the expanding young leaf on the top of stem could obtain 28% ∼ 59% of 14 C-assimilate at various potassium levels. Both the importation potential and rate were lowered with low potassium application while hastened by super-supplied potassium at the same development stage. At the filling stage, source, flag leaf, was able to export 83% ∼ 97% of its photosynthate and low potassium (5 ppm) application not only delayed the time of 14 C-photosynthate exportation but also diminished the export rate, whereas the rate was accelerated by superfluous potassium. Low potassium resulted in decrease both in the capacity and in the rate of assimilate importing into grain, nevertheless, high potassium caused decrease of percentage assimilate importing into grain and the increase of improving rate. Therefore, it was strategically considered that neither deficient nor superfluous potassium application was beneficial for assimilate transportation

Determination of potassium concentration in salt water for residual beta radioactivity measurements

International Nuclear Information System (INIS)

Suarez-Navarro, J.A.; Pujol, Ll.

2004-01-01

High interferences may arise in the determination of potassium concentration in salt water. Several analytical methods were studied to determine which method provided the most accurate measurements of potassium concentration. This study is relevant for radiation protection because the exact amount of potassium in water samples must be known for determinations of residual beta activity concentration. The fitting algorithm of the calibration curve and estimation of uncertainty in potassium determinations were also studied. The reproducibility of the proposed analytical method was tested by internal and external validation. Furthermore, the residual beta activity concentration of several Spanish seawater and brackish river water samples was determined using the proposed method
Gold Museum

OpenAIRE

Efraín Sánchez Cabra

2003-01-01

On 22 december 1939, the Banco de la República, the Central Bank of Colombia, purchased a 23.5 centimetres high pre-Columbian gold arte fact weighing 777·7 grams that was to become the Gold M useum's foundation stone. Described as a Quimbaya poporo, it is a masterpiece of pre-Hispanic goldwork, an object of beauty whose brightly burnished body and neck, crowned with four sphere-like or naments, rest on an exquisite cast metal tiligree base and which seems to ftoat in a space of its own. The b...
Gold nano-particles fixed on glass

International Nuclear Information System (INIS)

Worsch, Christian; Wisniewski, Wolfgang; Kracker, Michael; Rüssel, Christian

2012-01-01

Highlights: ► We produced wear resistant gold–ruby coatings on amorphous substrates. ► Thin sputtered gold layers were covered by or embedded in silica coatings. ► Annealing above T g of the substrate glass led to the formation of gold nano particles. ► A 1 1 1-texture of the gold particles is observed via XRD and EBSD. ► EBSD-patterns can be acquired from crystals covered by a thin layer of glass. - Abstract: A simple process for producing wear resistant gold nano-particle coatings on transparent substrates is proposed. Soda-lime-silica glasses were sputtered with gold and subsequently coated with SiO 2 using a combustion chemical vapor deposition technique. Some samples were first coated with silica, sputtered with gold and then coated with a second layer of silica. The samples were annealed for 20 min at either 550 or 600 °C. This resulted in the formation of round, well separated gold nano-particles with sizes from 15 to 200 nm. The color of the coated glass was equivalent to that of gold–ruby glasses. Silica/gold/silica coatings annealed at 600 °C for 20 min were strongly adherent and scratch resistant. X-ray diffraction and electron backscatter diffraction (EBSD) were used to describe the crystal orientations of the embedded particles. The gold particles are preferably oriented with their (1 1 1) planes perpendicular to the surface.
Studies in photo chromic behavior of some potassium hexacyanoferrate (2)-dye systems

International Nuclear Information System (INIS)

Taneja, Hanshu; Paliwala, Mukesh; Kumara Anil; Singh Sadhana; Ameta, Suresh C.; Ameta, Rameshwar

2009-01-01

The photo chromic behavior of potassium hexacyanoferrate (2)-fuchsin basic and potassium hexacyanoferrate (2)-malachite green systems was investigated in detail. The effect of variation of various parameters, like ph, light intensity, concentration of dyes, and concentration of potassium hexacyanoferrate(2), on the rates of forward and backward reactions of these systems has been observed. Based on experimental data, a tentative mechanism has also been proposed. (author)
Nature vs. nurture: gold perpetuates "stemness".

Science.gov (United States)

Paul, Willi; Sharma, Chandra P; Deb, Kaushik Dilip

2011-01-01

Adult tissues contain quiescent reservoirs of multipotent somatic stem cells and pluripotent embryonic-like stem cells (ELSCs). Credited with regenerative properties gold is used across both -contemporary and -ancient medicines. Here, we show that gold exerted these effects by enhancing the pool of pluripotent ELSC while improving their stemness. We used hESCs as an in-vitro model to understand if gold could enhance self-renewal and pluripotency. Swarna-bhasma (SB), an ancient Indian gold microparticulate (41.1 nm), preparation, reduced spontaneous-differentiation, improved self-renewal, pluripotency and proliferation of hESCs. Colloidal gold-nanoparticles (GNP) (15.59 nm) were tested to confirm that the observations were attributable to nanoparticulate-gold. SB and GNP exposure: maintained -stemness, -karyotypic stability, enhanced pluripotency till day-12, increased average colony-sizes, and reduced the number of autonomously-derived differentiated FGFR1 positive fibroblast-niche-cells/colony. Particulate-gold induced upregulation of FGFR1 and IGF2 expression, and decrease in IGF1 secretion indicates IGF1/2 mediated support for enhanced pluripotency and self-renewal in hESCs.
Aqueous two-phase systems of polyoxyethylene lauryl ether and potassium gluconate/potassium oxalate/potassium citrate at different temperature-experimental results and modeling of (liquid + liquid) equilibrium data

International Nuclear Information System (INIS)

Lu, Yang; Hao, Tongfan; Zhou, Yan; Han, Juan; Tan, Zhenjiang; Yan, Yongsheng

2014-01-01

Highlights: • The phase diagrams of POELE10-organic salts ATPSs were determined experimentally. • The experiential equations were used to correlate the binodal data. • The effect of salt on the binodal curve for the studied systems has been discussed. • The LLE data were correlated using the thermodynamic model. -- Abstract: The binodal data for the systems containing the POELE10 and KC 6 H 11 O 7 /K 2 C 2 O 4 /K 3 C 6 H 5 O 7 were determined at the T = (288.15, 298.15, 308.15) K. The three experiential equations were used to fit the binodal data and they achieved the satisfactory fitting effect. The effect of salt type on the phase-seperation ability of salt was studied. It was found that the phase-seperation ability of the salt with the higher valence anion is stronger than that with lower valence anion, namely, the order of the phase-seperation ability for the investigated salts is potassium citrate > potassium oxalate > potassium gluconate, which is also validated by the effective excluded volume (EEV). The (liquid + liquid) equilibrium data for the studied systems were determined and correlated by using the Pitzer–Debye–Hückel equation and Chen-NRTL model along with the Flory–Huggins equation, and good agreement was obtained with using these thermodynamic models
Does short-term potassium fertilization improve recovery from drought stress in laurel?

Science.gov (United States)

Oddo, Elisabetta; Inzerillo, Simone; Grisafi, Francesca; Sajeva, Maurizio; Salleo, Sebastiano; Nardini, Andrea

2014-08-01

Xylem hydraulic conductance varies in response to changes in sap solute content, and in particular of potassium (K(+)) ion concentration. This phenomenon, known as the 'ionic effect', is enhanced in embolized stems, where it can compensate for cavitation-induced loss of hydraulic conductance. Previous studies have shown that in well-watered laurel plants (Laurus nobilis L.), potassium concentration of the xylem sap and plant hydraulic conductance increased 24 h after fertilization with KCl. The aim of this work was to test whether water-stressed laurel plants, grown under low potassium availability, could recover earlier from stress when irrigated with a KCl solution instead of potassium-free water. Two-year-old potted laurel seedlings were subjected to water stress by suspending irrigation until leaf conductance to water vapour (g(L)) dropped to ∼30% of its initial value and leaf water potential (ψ(L)) reached the turgor loss point (ψ(TLP)). Plants were then irrigated either with water or with 25 mM KCl and monitored for water status, gas exchange and plant hydraulics recovery at 3, 6 and 24 h after irrigation. No significant differences were found between the two experimental groups in terms of ψ(L), g(L), plant transpiration, plant hydraulic conductance or leaf-specific shoot hydraulic conductivity. Analysis of xylem sap potassium concentration showed that there were no significant differences between treatments, and potassium levels were similar to those of potassium-starved but well-watered plants. In conclusion, potassium uptake from the soil solution and/or potassium release to the xylem appeared to be impaired in water-stressed plants, at least up to 24 h after relief from water stress, so that fertilization after the onset of stress did not result in any short-term advantage for recovery from drought. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
POTASSIUM FERTILIZATION AND SOIL MANAGEMENT SYSTEMS FOR COTTON CROPS

Directory of Open Access Journals (Sweden)

VITOR MARQUES VIDAL

2017-01-01

Full Text Available Cotton has great socio-economic importance due to its use in textile industry, edible oil and biodiesel production and animal feed. Thus, the objective of this work was to identify the best potassium rate and soil management for cotton crops and select among cultivars, the one that better develops in the climatic conditions of the Cerrado biome in the State of Goiás, Brazil. Thus, the effect of five potassium rates (100, 150, 200, 250 and 300 kg ha-1 of K2O and two soil management systems (no-till and conventional tillage on the growth, development and reproduction of four cotton cultivars (BRS-371, BRS-372, BRS-286 and BRS-201 was evaluated. The data on cotton growth and development were subjected to analysis of variance; the data on potassium rates were subjected to regression analysis; and the data on cultivars and soil management to mean test. The correlation between the vegetative and reproductive variables was also assessed. The conventional tillage system provides the best results for the herbaceous cotton, regardless of the others factors evaluated. The cultivar BRS-286 has the best results in the conditions evaluated. The cultivar BRS-371 under no-till system present the highest number of fruiting branches at a potassium rate of 105.5% and highest number of floral buds at a potassium rate of 96.16%. The specific leaf area was positively correlated with the number of bolls per plant at 120 days after emergence of the herbaceous cotton.
Carbonate hosted gold deposit in Tasmania, Australia

International Nuclear Information System (INIS)

Abadi, M.H.

1999-01-01

Full text: This study uses elemental and isotopic composition of carbonates associated with gold from Henty and Beaconsfield in Tasmania, Australia, to illustrate source of gold-bearing fluids, salinity, temperature and dissolution and reprecipitation of carbonate. The Beaconsfield and Henty gold mines are located in northern and western Tasmania respectively. Gold mineralisation in Beaconsfield occurs within the quartz-carbonate Tasmania Reef (Lower to Middle Palaeozoic sequence, Hills, 1998). The Henty gold mine is located at the base of the Cambrian Tyndall Group (volcano-sedimentary succession, White and McPhie, 1996) close to Henty Fault. Gold in carbonate samples from Henty ranges from 7.7 to 9360 ppm and in Beaconsfield ranges from 0.01 to 434 ppm. The amount of carbonate in samples from Henty and Beaconsfield gold mines varies from approximately 24 to 99.8%. Bivariate plot of Ca relative to total amounts of Mg, Fe and Mn illustrates that the major carbonate minerals at Beaconsfield and Henty gold mines are magnesian ankerite and calcite. The difference in carbonate mineralogy, at Henty and Beaconsfield gold mines, is attributed to the composition of fluids responsible for carbonate alteration. Gold and magnesium in Beaconsfield ankerite are derived from the leaching of Cambrian ultramafic rocks during the Devonian by the passage of meteoric fluids through tectonically affected Ordovician carbonates (Rao and Adabi, 1999). The total concentration of Fe and Mn are low (0.5 to 2%) in Henty and high (1 to 17.5%) in Beaconsfield ankerite, possibly due to oxidising conditions at Henty and reducing conditions at Beaconsfield gold mines during gold mineralisation. Variation of Sr values between Beaconsfield ankerite and Henty calcite is related to dissolution of limestone that increase Sr concentrations in gold mineralising fluids. Na values in both Beaconsfield (20 to 1100 ppm) and Henty carbonates (25 to 1650 ppm) suggest low salinity fluids responsible for gold
A Preliminary Study on Detecting Fake Gold Bars Using Prompt Gamma Activation Analysis: Simulation of Neutron Transmission in Gold Bar

Energy Technology Data Exchange (ETDEWEB)

Lee, K. M.; Sun, G. M. [KAERI, Daejeon (Korea, Republic of)

2016-05-15

The purpose of this study is to develop fake gold bar detecting method by using Prompt-gamma activation analysis (PGAA) facility at the Korea Atomic Energy Research Institute (KAERI). PGAA is an established nuclear analytical technique for non-destructive determination of elemental and isotopic compositions. For a preliminary study on detecting fake gold bar, Monte Carlo simulation of neutron transmission in gold bar was conducted and the possibility for detecting fake gold bar was confirmed. Under the gold bullion standard, it guaranteed the government would redeem any amount of currency for its value in gold. After the gold bullion standard ended, gold bars have been the target for investment as ever. But it is well known that fake gold bar exist in the gold market. This cannot be identified easily without performing a testing as it has the same appearance as the pure gold bar. In order to avoid the trading of fake gold bar in the market, they should be monitored thoroughly. Although the transmissivity of cold neutrons are low comparing that of thermal neutrons, the slower neutrons are more apt to be absorbed in a target, and can increase the prompt gamma emission rate. Also the flux of both thermal and cold neutron beam is high enough to activate thick target. If the neutron beam is irradiated on the front and the reverse side of gold bar, all insides of it can be detected.
A Preliminary Study on Detecting Fake Gold Bars Using Prompt Gamma Activation Analysis: Simulation of Neutron Transmission in Gold Bar

International Nuclear Information System (INIS)

Lee, K. M.; Sun, G. M.

2016-01-01

The purpose of this study is to develop fake gold bar detecting method by using Prompt-gamma activation analysis (PGAA) facility at the Korea Atomic Energy Research Institute (KAERI). PGAA is an established nuclear analytical technique for non-destructive determination of elemental and isotopic compositions. For a preliminary study on detecting fake gold bar, Monte Carlo simulation of neutron transmission in gold bar was conducted and the possibility for detecting fake gold bar was confirmed. Under the gold bullion standard, it guaranteed the government would redeem any amount of currency for its value in gold. After the gold bullion standard ended, gold bars have been the target for investment as ever. But it is well known that fake gold bar exist in the gold market. This cannot be identified easily without performing a testing as it has the same appearance as the pure gold bar. In order to avoid the trading of fake gold bar in the market, they should be monitored thoroughly. Although the transmissivity of cold neutrons are low comparing that of thermal neutrons, the slower neutrons are more apt to be absorbed in a target, and can increase the prompt gamma emission rate. Also the flux of both thermal and cold neutron beam is high enough to activate thick target. If the neutron beam is irradiated on the front and the reverse side of gold bar, all insides of it can be detected
Integrated process using non-stoichiometric sulfides or oxides of potassium for making less active metals and hydrocarbons

International Nuclear Information System (INIS)

Swanson, R.

1984-01-01

Disclosed is a combinative integrated chemical process using inorganic reactants and yielding, if desired, organic products. The process involves first the production of elemental potassium by the thermal or thermal-reduced pressure decomposition of potassium oxide or potassium sulfide and distillation of the potassium. This elemental potassium is then used to reduce ores or ore concentrates of copper, zinc, lead, magnesium, cadmium, iron, arsenic, antimony or silver to yield one or more of these less active metals in elemental form. Process potassium can also be used to produce hydrogen by reaction with water or potassium hydroxide. This hydrogen is reacted with potassium to produce potassium hydride. Heating the latter with carbon produces potassium acetylide which forms acetylene when treated with water. Acetylene is hydrogenated to ethene or ethane with process hydrogen. Using Wurtz-Fittig reaction conditions, the ethane can be upgraded to a mixture of hydrocarbons boiling in the fuel range
Radiation Doses to Hanford Workers from Natural Potassium-40

Energy Technology Data Exchange (ETDEWEB)

Strom, Daniel J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lynch, Timothy P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weier, Dennis R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2009-02-01

The chemical element potassium is an essential mineral in people and is subject to homeostatic regulation. Natural potassium comprises three isotopes, ³⁹K, ⁴⁰K, and ⁴¹K. Potassium-40 is radioactive, with a half life of 1.248 billion years. In most transitions, it emits a β particle with a maximum energy of 0.560 MeV, and sometimes a gamma photon of 1.461 MeV. Because it is ubiquitous, ⁴⁰K produces radiation dose to all human beings. This report contains the results of new measurements of ⁴⁰K in 248 adult females and 2,037 adult males performed at the Department of Energy Hanford Site in 2006 and 2007. Potassium concentrations diminish with age, are generally lower in women than in men, and decrease with body mass index (BMI). The average annual effective dose from ⁴⁰K in the body is 0.149 mSv y^-1 for men and 0.123 mSv y^-1 women respectively. Averaged over both men and women, the average effective dose per year is 0.136 mSv y^-1. Calculated effective doses range from 0.069 to 0.243 mSv y^-1 for adult males, and 0.067 to 0.203 mSv y^-1 for adult females, a roughly three-fold variation for each gender. The need for dosimetric phantoms with a greater variety of BMI values should be investigated. From our data, it cannot be determined whether the potassium concentration in muscle in people with large BMI values differs from that in people with small BMI values. Similarly, it would be important to know the potassium concentration in other soft tissues, since much of the radiation dose is due to beta radiation, in which the source and target tissues are the same. These uncertainties should be evaluated to determine their consequences for dosimetry.
Gold ions bio-released from metallic gold particles reduce inflammation and apoptosis and increase the regenerative responses in focal brain injury

DEFF Research Database (Denmark)

Larsen, Agnete; Kolind, Kristian; Pedersen, Dan Sonne

2008-01-01

neural stem cell response. We conclude that bio-liberated gold ions possess pronounced anti-inflammatory and neuron-protective capacities in the brain and suggest that metallic gold has clinical potentials. Intra-cerebral application of metallic gold as a pharmaceutical source of gold ions represents......Traumatic brain injury results in loss of neurons caused as much by the resulting neuroinflammation as by the injury. Gold salts are known to be immunosuppressive, but their use are limited by nephrotoxicity. However, as we have proven that implants of pure metallic gold release gold ions which do...... not spread in the body, but are taken up by cells near the implant, we hypothesize that metallic gold could reduce local neuroinflammation in a safe way. Bio-liberation, or dissolucytosis, of gold ions from metallic gold surfaces requires the presence of disolycytes i.e. macrophages and the process...
Sodium and potassium urinary excretion levels of preschool children: Individual, daily, and seasonal differences.

Science.gov (United States)

Yasutake, Kenichiro; Nagafuchi, Mikako; Izu, Ryoji; Kajiyama, Tomomi; Imai, Katsumi; Murata, Yusuke; Ohe, Kenji; Enjoji, Munechika; Tsuchihashi, Takuya

2017-06-01

In this study, the authors measured sodium and potassium concentrations in spot urine samples of preschool children on multiple days, and evaluated individual, daily, and seasonal effects. A total of 104 healthy preschool children aged 4 to 5 years were studied. Urine samples were collected from the first urine of the day after waking for three consecutive days (Monday-Wednesday) four times a year (spring, summer, autumn, winter). The authors estimated the daily urine volume as 500 mL and daily creatinine excretion as 300 mg, and used these to calculate daily sodium and potassium excretion levels. Daily sodium and potassium excretion levels and sodium to potassium ratios were highly variable. The coefficient variant in the children's excretion levels were also high within and between individuals. Sodium excretion levels and sodium to potassium ratios were higher on Monday (weekend sodium intakes) than Tuesday. Season had no effect on sodium or potassium excretion levels, but the sodium to potassium ratio was higher in summer than in winter. In conclusion, levels of urinary sodium excretion are comparatively high and those of potassium are low in preschool students, with high variability within and between individuals. ©2017 Wiley Periodicals, Inc.
Investigation of iodine liberation process in redox titration of potassium iodate with sodium thiosulfate

International Nuclear Information System (INIS)

Asakai, Toshiaki; Hioki, Akiharu

2011-01-01

Potassium iodate is often used as a reference material to standardize a sodium thiosulfate solution which is a familiar titrant for redox titrations. In the standardization, iodine (triiodide) liberated by potassium iodate in an acidic potassium iodide solution is titrated with a sodium thiosulfate solution. The iodine liberation process is significantly affected by the amount of acid, that of potassium iodide added, the waiting time for the liberation, and light; therefore, the process plays a key role for the accuracy of the titration results. Constant-voltage biamperometry with a modified dual platinum-chip electrode was utilized to monitor the amount of liberated iodine under several liberation conditions. Coulometric titration was utilized to determine the concentration of a sodium thiosulfate solution on an absolute basis. Potassium iodate was assayed by gravimetric titration with the sodium thiosulfate solution under several iodine liberation conditions. The liberation process was discussed from the changes in the apparent assay of potassium iodate. The information of the appropriate titration procedure obtained in the present study is useful for any analysts utilizing potassium iodate to standardize a thiosulfate solution.
Investigation of iodine liberation process in redox titration of potassium iodate with sodium thiosulfate

Energy Technology Data Exchange (ETDEWEB)

Asakai, Toshiaki, E-mail: t-asakai@aist.go.jp [National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 3-9, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8563 (Japan); Hioki, Akiharu [National Metrology Institute of Japan (NMIJ), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba Central 3-9, 1-1-1 Umezono, Tsukuba, Ibaraki 305-8563 (Japan)

2011-03-09

Potassium iodate is often used as a reference material to standardize a sodium thiosulfate solution which is a familiar titrant for redox titrations. In the standardization, iodine (triiodide) liberated by potassium iodate in an acidic potassium iodide solution is titrated with a sodium thiosulfate solution. The iodine liberation process is significantly affected by the amount of acid, that of potassium iodide added, the waiting time for the liberation, and light; therefore, the process plays a key role for the accuracy of the titration results. Constant-voltage biamperometry with a modified dual platinum-chip electrode was utilized to monitor the amount of liberated iodine under several liberation conditions. Coulometric titration was utilized to determine the concentration of a sodium thiosulfate solution on an absolute basis. Potassium iodate was assayed by gravimetric titration with the sodium thiosulfate solution under several iodine liberation conditions. The liberation process was discussed from the changes in the apparent assay of potassium iodate. The information of the appropriate titration procedure obtained in the present study is useful for any analysts utilizing potassium iodate to standardize a thiosulfate solution.
Serum Potassium Levels and Outcome in Acute Heart Failure (Data from the PROTECT and COACH Trials).

Science.gov (United States)

Tromp, Jasper; Ter Maaten, Jozine M; Damman, Kevin; O'Connor, Christopher M; Metra, Marco; Dittrich, Howard C; Ponikowski, Piotr; Teerlink, John R; Cotter, Gad; Davison, Beth; Cleland, John G F; Givertz, Michael M; Bloomfield, Daniel M; van der Wal, Martje H L; Jaarsma, Tiny; van Veldhuisen, Dirk J; Hillege, Hans L; Voors, Adriaan A; van der Meer, Peter

2017-01-15

Serum potassium is routinely measured at admission for acute heart failure (AHF), but information on association with clinical variables and prognosis is limited. Potassium measurements at admission were available in 1,867 patients with AHF in the original cohort of 2,033 patients included in the Patients Hospitalized with acute heart failure and Volume Overload to Assess Treatment Effect on Congestion and Renal FuncTion trial. Patients were grouped according to low potassium (5.0 mEq/l) levels. Results were verified in a validation cohort of 1,023 patients. Mean age of patients was 71 ± 11 years, and 66% were men. Low potassium was present in 115 patients (6%), normal potassium in 1,576 (84%), and high potassium in 176 (9%). Potassium levels increased during hospitalization (0.18 ± 0.69 mEq/l). Patients with high potassium more often used angiotensin-converting enzyme inhibitors and mineralocorticoid receptor antagonists before admission, had impaired baseline renal function and a better diuretic response (p = 0.005), independent of mineralocorticoid receptor antagonist usage. During 180-day follow-up, a total of 330 patients (18%) died. Potassium levels at admission showed a univariate linear association with mortality (hazard ratio [log] 2.36, 95% confidence interval 1.07 to 5.23; p = 0.034) but not after multivariate adjustment. Changes of potassium levels during hospitalization or potassium levels at discharge were not associated with outcome after multivariate analysis. Results in the validation cohort were similar to the index cohort. In conclusion, high potassium levels at admission are associated with an impaired renal function but a better diuretic response. Changes in potassium levels are common, and overall levels increase during hospitalization. In conclusion, potassium levels at admission or its change during hospitalization are not associated with mortality after multivariate adjustment. Copyright © 2016 The Authors. Published by Elsevier Inc
Intensification Behavior of Mercury Ions on Gold Cyanide Leaching

Directory of Open Access Journals (Sweden)

Qiang Zhong

2018-01-01

Full Text Available Cyanidation is the main method used to extract gold from gold raw materials; however, a serious problem with this method is the low leaching rate. In order to improve gold leaching, the intensification behavior of mercury ions on gold cyanide leaching, for two types of materials, sulphide gold concentrate and oxide gold ore, was investigated. The results showed that mercury ions, with only a 10−5 M dosage, could significantly intensify leaching and gold recovery. The dissolution behavior of gold plate was also intensified by 10−5 M mercury ions. Microstructure analysis showed that mercury ions intensified the cyanidation corrosion of the gold surface, resulting in a loose structure, where a large number of deep ravines and raised particles were evident across the whole gold surface. The loose structure added contact surface between the gold and cyanide, and accelerated gold dissolution. Moreover, mercury ions obstructed the formation of insoluble products, such as AuCN, Au(OHCN, and Au(OHx, that lead to a passivation membrane on the gold surface, reducing contact between the gold and cyanide. These effects, brought about by mercury ions, change the structure and product of the gold surface during gold cyanidation and promote gold leaching.
Effect of nitrogen and potassium fertilization on radiocesium absorption in soybean

International Nuclear Information System (INIS)

Nihei, Naoto; Hirose, Atsushi; Tanoi, Keitaro; Nakanishi, Tomoko M.

2015-01-01

Radioactive materials that were released during the nuclear accident contaminated the soil and agricultural products. It has become clear that potassium fertilization is effective for the reduction of radiocesium concentrations in agricultural crops. However, apart from reports about potassium, few reports have examined how nitrogen, which has a large effect on crop growth, contributes to the radiocesium absorption. Focusing on this point, we studied the effect of nitrogen and potassium fertilizer on the radiocesium absorption in soybean seedlings. The concentration of radiocesium in the seed of soybean was higher in nitrogen-fertilized plants than in plants grown without fertilizer. The radiocesium concentration in the aboveground biomass increased as the amount of nitrogen fertilization increased. But the concentrations of radiocesium were higher in potassium-fertilized plants at high-N than in plants without added nitrogen and potassium. Further study is required to clarify the factors that incur an increase in radiocesium concentration in response to nitrogen fertilization. Special care is required to start farming soybean on fallow fields evacuated after the accident or on fields where rice has been grown before, which tend to have higher available nitrogen than the regularly cultivated fields. (author)

Dietary Sodium/Potassium Intake Does Not Affect Cognitive Function or Brain Imaging Indices.

Science.gov (United States)

Nowak, Kristen L; Fried, Linda; Jovanovich, Anna; Ix, Joachim; Yaffe, Kristine; You, Zhiying; Chonchol, Michel

2018-01-01

Dietary sodium may influence cognitive function through its effects on cerebrovascular function and cerebral blood flow. The aim of this study was to evaluate the association of dietary sodium intake with cognitive decline in community-dwelling older adults. We also evaluated the associations of dietary potassium and sodium:potassium intake with cognitive decline, and associations of these nutrients with micro- and macro-structural brain magnetic resonance imaging (MRI) indices. In all, 1,194 participants in the Health Aging and Body Composition study with measurements of dietary sodium intake (food frequency questionnaire [FFQ]) and change in the modified Mini Mental State Exam (3MS) were included. The age of participants was 74 ± 3 years with a mean dietary sodium intake of 2,677 ± 1,060 mg/day. During follow-up (6.9 ± 0.1 years), 340 (28%) had a clinically significant decline in 3MS score (≥1.5 SD of mean decline). After adjustment, dietary sodium intake was not associated with odds of cognitive decline (OR 0.96, 95% CI 0.50-1.84 per doubling of sodium). Similarly, potassium was not associated with cognitive decline; however, higher sodium:potassium intake was associated with increased odds of cognitive decline (OR 2.02 [95% CI 1.01-4.03] per unit increase). Neither sodium or potassium alone nor sodium:potassium were associated with micro- or macro-structural brain MRI indices. These results are limited by the use of FFQ. In community-dwelling older adults, higher sodium:potassium, but not sodium or potassium intake alone, was associated with decline in cognitive function, with no associations observed with micro- and macro-structural brain MRI indices. These findings do not support reduction dietary sodium/increased potassium intake to prevent cognitive decline with aging. © 2018 S. Karger AG, Basel.
Potassium sensing histidine kinase in Bacillus subtilis.

Science.gov (United States)

López, Daniel; Gontang, Erin A; Kolter, Roberto

2010-01-01

The soil-dwelling organism Bacillus subtilis is able to form multicellular aggregates known as biofilms. It was recently reported that the process of biofilm formation is activated in response to the presence of various, structurally diverse small-molecule natural products. All of these small-molecule natural products made pores in the membrane of the bacterium, causing the leakage of potassium cations from the cytoplasm of the cell. The potassium cation leakage was sensed by the membrane histidine kinase KinC, triggering the genetic pathway to the production of the extracellular matrix that holds cells within the biofilm. This chapter presents the methodology used to characterize the leakage of cytoplasmic potassium as the signal that induces biofilm formation in B. subtilis via activation of KinC. Development of novel techniques to monitor activation of gene expression in microbial populations led us to discover the differentiation of a subpopulation of cells specialized to produce the matrix that holds all cells together within the biofilm. This phenomenon of cell differentiation was previously missed by conventional techniques used to monitor transcriptional gene expression. Copyright © 2010 Elsevier Inc. All rights reserved.
Stoichiometry of Na/Ca antiport obtained by magnesium inhibition in cultured vascular smooth muscle cells

International Nuclear Information System (INIS)

Smith, J.B.; Higgins, B.L.; Smith, L.

1987-01-01

Cultured smooth muscle cells from rat aorta were loaded with Na, and Na/Ca antiport was assayed by measuring the initial rates of 45 Ca influx and 22 Na efflux. The replacement of extracellular Na with other monovalent ions, usually N-methyl-D-glucamine (NMG), was essential for obtaining significant antiport activity. Mg competitively inhibited 45 Ca influx via the antiporter (Ki = 100 uM). External Ca stimulated 22 Na efflux as expected for antiport activity. Mg did not stimulate 22 Na efflux indicating that Mg is not transported by the antiporter. Mg inhibited Ca-stimulated 22 Na efflux as expected from the 45 Ca influx data. The stoichiometry of the antiporter was calculated from the changes in the rates of 45 Ca influx and 22 Na efflux at 3 Mg concentrations: 2.87 +/- 0.25 (mean +/- SE, n=5). The replacement of external NMG with potassium, but not other monovalent ions (choline, Li), decreased the potency of Mg as an inhibitor of Na/Ca antiport by about 6 fold. Other divalent cations (Co, Mn, Cd, Ba) inhibited Na/Ca antiport and high external potassium decreased the potency of each by about 6 fold. The order of effectiveness of the divalent cations as inhibitors of Na/Ca antiport (Cd>Mn>Co>Ba>Mg) correlated with the crystal ionic radius of the cation
Potassium and soot interaction in fast biomass pyrolysis at high temperatures

DEFF Research Database (Denmark)

Trubetskaya, Anna; Hofmann Larsen, Flemming; Shchukarev, Andrey

2018-01-01

2 reactivity was studied by thermogravimetric analysis. The XPS results showed that potassium incorporation with oxygen-containing surface groups in the soot matrix did not occur during high temperature pyrolysis. The potassium was mostly found as water-soluble salts such as KCl, KOH, KHCO3 and K2CO...... potassium amount was incorporated in the soot matrix during pyrolysis. Raman spectroscopy results showed that the carbon chemistry of biomass soot also affected the CO2 reactivity. The less reactive pinewood soot was more graphitic than herbaceous biomass soot samples with the disordered carbon structure...
Green Gold

International Nuclear Information System (INIS)

Salamandra Martinez, Carlos

2004-01-01

The main purpose of this work is to offer a general panoramic of the processes or experiences pilot that are carried out in the Project Green Gold, as strategy of environmental sustainability and organizational invigoration in Choco, especially in the 12 communities of the municipalities of Tado and Condoto. It is also sought to offer a minimum of information on the techniques of handmade production and to show the possibilities to carry out in a rational way the use and use of the natural resources. The Project Green Gold is carried out by the Corporation Green Gold (COV) and co-financed with resources of international and national character, the intervention of the financial resources it achievement mainly for the use of clean processes in the extraction stages and metals benefit. The project is centered primarily in the absence of use of products or toxic substances as the mercury, fair trade, organizational invigoration, execution of 11 approaches and certification of the metals Gold and Platinum. The COV, it has come executing the proposal from the year 2001 with the premise of contributing to the balance between the rational exploitation of the natural resources and the conservation of the environment in the Choco. In the project they are used technical handmade characteristic of the region framed inside the mining activity and production activities are diversified in the productive family units. Those producing with the support of entities of juridical character, specify the necessary game rules for the extraction and products commercialization
Gold nanoparticles produced in a microalga

International Nuclear Information System (INIS)

Luangpipat, Tiyaporn; Beattie, Isabel R.; Chisti, Yusuf; Haverkamp, Richard G.

2011-01-01

An efficient biological route to production of gold nanoparticles which allows the nanoparticles to be easily recovered remains elusive. Live cells of the green microalga Chlorella vulgaris were incubated with a solution of gold chloride and harvested by centrifugation. Nanoparticles inside intact cells were identified by transmission electron microscopy and confirmed to be metallic gold by synchrotron based X-ray powder diffraction and X-ray absorption spectroscopy. These intracellular gold nanoparticles were 40–60 nm in diameter. At a concentration of 1.4% Au in the alga, a better than 97% recovery of the gold from solution was achieved. A maximum of 4.2% Au in the alga was obtained. Exposure of C. vulgaris to solutions containing dissolved salts of palladium, ruthenium, and rhodium also resulted in the production of the corresponding nanoparticles within the cells. These were surmised to be also metallic, but were produced at a much lower intracellular concentration than achieved with gold. Iridium was apparently toxic to the alga. No nanoparticles were observed using platinum solutions. C. vulgaris provides a possible route to large scale production of gold nanoparticles.
Gold Nanoparticle Mediated Phototherapy for Cancer

International Nuclear Information System (INIS)

Yao, C.; Zhang, L.; Wang, J.; He, Y.; Xin, J.; Wang, S.; Xu, H.; Zhang, Z.

2016-01-01

Gold nanoparticles exhibit very unique physiochemical and optical properties, which now are extensively studied in range of medical diagnostic and therapeutic applications. In particular, gold nanoparticles show promise in the advancement of cancer treatments. This review will provide insights into the four different cancer treatments such as photothermal therapy, gold nanoparticle-aided photodynamic therapy, gold nanoparticle-aided radiation therapy, and their use as drug carrier. We also discuss the mechanism of every method and the adverse effects and its limitations
Surface modification of silica particles with gold nanoparticles as an augmentation of gold nanoparticle mediated laser perforation

Science.gov (United States)

Kalies, Stefan; Gentemann, Lara; Schomaker, Markus; Heinemann, Dag; Ripken, Tammo; Meyer, Heiko

2014-01-01

Gold nanoparticle mediated (GNOME) laser transfection/perforation fulfills the demands of a reliable transfection technique. It provides efficient delivery and has a negligible impact on cell viability. Furthermore, it reaches high-throughput applicability. However, currently only large gold particles (> 80 nm) allow successful GNOME laser perforation, probably due to insufficient sedimentation of smaller gold nanoparticles. The objective of this study is to determine whether this aspect can be addressed by a modification of silica particles with gold nanoparticles. Throughout the analysis, we show that after the attachment of gold nanoparticles to silica particles, comparable or better efficiencies to GNOME laser perforation are reached. In combination with 1 µm silica particles, we report laser perforation with gold nanoparticles with sizes down to 4 nm. Therefore, our investigations have great importance for the future research in and the fields of laser transfection combined with plasmonics. PMID:25136494
Linear Optical Properties of Gold Colloid

Directory of Open Access Journals (Sweden)

Jingmin XIA

2015-11-01

Full Text Available Gold colloid was prepared by reducing HAuCl4·4H2O with Na3C6H5O7·2H2O. The morphology, size of gold nanoparticles and the optical property of colloid were characterized by transmission electron microscope and UV-Vis spectrophotometer, respectively. It shows that the gold nanoparticles are in the shape of spheres with diameters less than 8 nm, and the surface plasmon resonance absorption peak is located at about 438 nm. As the volume fraction of gold particles increases, the intensity of absorption peak strengthens. The optical property of gold colloid was analyzed by Maxwell-Garnett (MG effective medium theory in the company of Drude dispersion model. The results show that the matrix dielectric constant is a main factor, which influences the optical property of gold colloid.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9558
Skin decontamination efficacy of potassium ketoxime on rabbits exposed to sulfur mustard.

Science.gov (United States)

Sun, Jing-Hai; Sun, Pei-Pei; Zheng, Wei; Han, Song; Ying, Ying; Liu, Hong-Yan; Zhang, Cheng; Zhao, Bao-Quan; Zuo, Guo-Min; Lu, Hong; Zhong, Yu-Xu

2015-03-01

The chemical weapon sulfur mustard (SM) is a blister agent, and currently, there is no effective antidote. To evaluate the decontamination efficacy of potassium ketoxime against SM and preliminarily elucidate its decontamination mechanism. Potassium ketoxime reacted with SM, and SM residues were tested at different time intervals by T-135 colorimetry after the reaction. Rabbit skin was topically exposed to 2 mg/cm(2) SM, treated with potassium ketoxime 1 min later, and observed after 6, 12, and 24 h. Gas chromatography-mass spectroscopy was employed to screen and identify the main products of potassium ketoxime decontamination of SM. Potassium ketoxime had a great effect against SM contamination. With a mass ratio of decontaminant: SM of 50:1, decontamination rates against SM were 87.5% after 30 s, 95.9% after 1 min, and 99.0% after 5 min. Fifteen minutes after exposure to SM, the untreated group showed clear erythema lesions, whereas the experimental group showed no clear erythema lesions within 6 h. After 12 and 24 h, the areas of damaged skin in the experimental group were 0.038 and 0.125 cm(2), respectively, compared with 2.21 and 2.65 cm(2) in the control group. Histopathological analysis revealed that treatment with potassium ketoxime also reduced inflammation-induced damage. The results of this study indicate that potassium ketoxime reacted rapidly and completely with SM, and thus, it was found to be a suitable and effective skin decontaminant against SM. The decontamination reaction mechanism is mainly related to nucleophilic substitution.
Impact of potassium bromate and potassium iodate in a pound cake system.

Science.gov (United States)

Wilderjans, Edith; Lagrain, Bert; Brijs, Kristof; Delcour, Jan A

2010-05-26

This study investigates the impact of the oxidants potassium bromate and potassium iodate (8, 16, 32, 64, and 128 micromol/g dry matter of egg white protein) on pound cake making. The impact of the oxidants on egg white characteristics was studied in a model system. Differential scanning calorimetry showed that the oxidants caused egg white to denature later. During heating in a rapid visco analyzer, the oxidants caused the free sulfhydryl (SH) group levels to decrease more intensively and over a smaller temperature range. The oxidants made the proteins more resistant to decreases in protein extractability in sodium dodecyl sulfate containing buffer during cake recipe mixing and less resistant to such decreases during cake baking. We assume that, during baking, the degree to which SH/disulfide exchange and SH oxidation can occur depends on the properties of the protein at the onset of the process. In our view, the prevention of extractability loss during mixing increased the availability of SH groups and caused more such loss during baking. During cooling, all cakes baked with added oxidants showed less collapse. On the basis of the presented data, we put forward that only those protein reactions that occur during baking contribute to the formation of a network that supports final cake structure and prevents collapse.
Coal-oil assisted flotation for the gold recovery

Energy Technology Data Exchange (ETDEWEB)

Sen, S.; Seyrankaya, A.; Cilingir, Y. [Dokuz Eylul University, Izmir (Turkey). Mining Engineering Department

2005-09-01

Using coal-oil agglomeration method for free or native gold recovery has been a research subject for many researchers over the years. In this study, a new approach 'coal-oil assisted gold flotation' was used to recover gold particles. The coal-oil-gold agglomeration process considers the preferential wetting of coal and gold particles. The method takes advantage of the greater hydrophobicity and oleophilicity of coal and gold compared to that the most gangue materials. Unlike the previous studies about coal-oil-gold agglomeration, this method uses a very small amount of coal and agglomerating agents. Some experiments were conducted on synthetic gold ore samples to reveal the reaction of the coal-oil assisted gold flotation process against the size and the number of gold particles in the feed. It was observed that there is no significant difference in process gold recoveries for feeds assaying different Au. Although there was a slight decrease for coarse gold particles, the process seems to be effective for the recovery of gold grains as coarse as 300 {mu} m. The decrease in the finest size ({lt} 53 {mu} m) is considered to be the decrease in the collision efficiency between the agglomerates and the finest gold particles. The effect of changing coal quantity for constant ore and oil amounts was also investigated. The experiments showed that the process gives very similar results for both artificial and natural ore samples; the best results have been obtained by using 30/1 coal-oil ratio.
The effect of potassium nutrition on sup 137 Cs uptake in two upland species

Energy Technology Data Exchange (ETDEWEB)

Jones, H E; Harrison, A F; Poskitt, J M; Roberts, J D; Clint, G [Institute for Terrestrial Ecology, Grange-over-Sands (UK)

1991-01-01

Agrostis capillaris (Agrostis) and Calluna vulgaris (Calluna), two species with differing phenologies and widespread presence in upland areas of Britain where high Chernobyl fallout occurred, were grown in pot culture with varying concentrations of potassium in the rooting medium. Tissue content of potassium increased with increasing supply in both species. Roots, excised from these plants, were placed in a solution of {sup 137}Cs-labelled caesium chloride for 15 min to determine uptake potential. There were clear negative relationships between the rate of uptake of {sup 137}Cs by both species and (a) the concentration of potassium supplied and (b) plant issue potassium concentrations. With Agrotis, there was an approximately ten-fold difference in {sup 137}Cs uptake between potassium-deficient and optimum plants; with Calluna, it was approximately eight-fold. These results demonstrate the suppression of {sup 137}Cs uptake into plants by potassium supply. (author).
Potassium bromate content of some baked breads sold in Kano ...

African Journals Online (AJOL)

Background: Potassium bromate is an additive used by some bakers to make the bread rise rapidly, create a good texture in the finished product and to give bulkiness to the dough. Objective: The main objective of this work was to assess the potassium bromate residues of some baked breads sold in some selected local ...
Status of potassium permanganate - 2008

Science.gov (United States)

This is a brief overview of the Technical Sections completed and being worked on for the New Animal Drug Application (NADA) for potassium permanganate will be presented. Initial Label Claim (Columnaris on catfish/HSB): 1) Human Food Safety - Complete for all fin fish (June 1999). A hazard charac...
Modification of thermal sensitivity of Chinese hamster cells by exposure to solutions of monovalent and divalent cationic salts

International Nuclear Information System (INIS)

Raaphorst, G.P.; Azzam, E.I.; Vadasz, J.

1984-06-01

Chinese hamster V79 cells were heated in culture medium or in 0.155-mol.dm -3 solutions of LiCl, NaCl, KCl, MgCl 2 , CaCl 2 and BaCl 2 . The presence of any one of these ionic solutions during heating increased the thermal sensitivity of the cells. The order of increased thermal sensitivity was KCl > LiCl > NaCl for the monovalent salts and BaCl 2 > MgCl 2 > CaCl 2 for the divalent cation salts. The addition of glucose to LiCl or NaCl solutions did not reduce the thermal sensitization caused by these solutions. When cells were sensitized by LiCl or NaCl treatment, a change in pH from 7.2 to 6.6 did not further increase thermal sensitivity. These data show that nutrient and ionic factors and their interplay are involved in cellular thermal sensitivity
Performance analysis of a potassium-base AMTEC cell

International Nuclear Information System (INIS)

Huang, C.; Hendricks, T.J.; Hunt, T.K.

1998-01-01

Sodium-BASE Alkali-Metal-Thermal-to-Electric-Conversion (AMTEC) cells have been receiving increased attention and funding from the Department of Energy, NASA and the United States Air Force. Recently, sodium-BASE (Na-BASE) AMTEC cells were selected for the Advanced Radioisotope Power System (ARPS) program for the next generation of deep-space missions and spacecraft. Potassium-BASE (K-BASE) AMTEC cells have not received as much attention to date, even though the vapor pressure of potassium is higher than that of sodium at the same temperature. So that, K-BASE AMTEC cells with potentially higher open circuit voltage and higher power output than Na-BASE AMTEC cells are possible. Because the surface tension of potassium is about half of the surface tension of sodium at the same temperature, the artery and evaporator design in a potassium AMTEC cell has much more challenging pore size requirements than designs using sodium. This paper uses a flexible thermal/fluid/electrical model to predict the performance of a K-BASE AMTEC cell. Pore sizes in the artery of K-BASE AMTEC cells must be smaller by an order of magnitude than in Na-BASE AMTEC cells. The performance of a K-BASE AMTEC cell was higher than a Na-BASE AMTEC cell at low voltages/high currents. K-BASE AMTEC cells also have the potential of much better electrode performance, thereby creating another avenue for potentially better performance in K-BASE AMTEC cells
Direct determination of thermodynamic activities of gold in the systems gold-palladium and gold-silver-palladium

International Nuclear Information System (INIS)

Hoehn, R.; Herzig, C.

1986-01-01

The thermodynamic activity of the gold component was directly measured in Au-Pd alloys in the concentration range between X Au =0.048 and 0.850 and in the temperature range 1070 and 1300 K. The ratio of the vapour pressures of pure gold and of the gold component of the alloys was determined - after effusion from a Knudsen twin cell and condensation on a collecting plate - by analysing the decay rate of the radioisotopes 195 Au and 198 Au in an intrinsic germanium well-type detector. The partial mixing enthalpy and the partial mixing entropy of Au were directly obtained from these results. By Gibbs-Duhem integration the integral mixing functions were deduced. Similar measurements were performed in several ternary Au-Ag-Pd alloys of fixed mole fraction X Ag /X Pd =1/9. A comparison of the directly measured partial free excess enthalpy of Au in these ternary alloys with data obtained by the approximate models of Kohler, Toop and Bonnier using data of the corresponding three binary systems yields satisfactory agreement. (orig.) [de
Cancer caused by radioactive gold rings

International Nuclear Information System (INIS)

Callary, E.M.

1989-01-01

Two recent cases of skin cancer caused by radioactive gold rings are described. The gold was contaminated with radon daughters from hollow goldseeds used to hold radon, back in the 1930s or possibly later. Other radioactive gold rings are probably being worn. The Canadian AECB offers free testing
Synthesis of camptothecin-loaded gold nanomaterials

International Nuclear Information System (INIS)

Xing Zhimin; Liu Zhiguo; Zu Yuangang; Fu Yujie; Zhao Chunjian; Zhao Xiuhua; Meng Ronghua; Tan Shengnan

2010-01-01

Camptothecin-loaded gold nanomaterials have been synthesized by the sodium borohydride reduction method under a strong basic condition. The obtained gold nanomaterials have been characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM) and UV-vis absorption spectroscopy. The camptothecin-loaded gold colloidal solution was very stable and can be stored for more than two months at room temperature without obvious changes. The color of the colloidal solution can change from wine red to purple and blue during the acidifying process. It was revealed that the release of camptothecin and the aggregation of gold nanoparticles can be controlled by tuning the solution pH. The present study implied that the gold nanomaterials can be used as the potential carrier for CPT delivery.

Synthesis of camptothecin-loaded gold nanomaterials

Energy Technology Data Exchange (ETDEWEB)

Xing Zhimin [Key Laboratory of Forest Plant Ecology of Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Engineering Research Center of Forest Bio-preparation, Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Liu Zhiguo, E-mail: zguoliu@yahoo.com.cn [Key Laboratory of Forest Plant Ecology of Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Engineering Research Center of Forest Bio-preparation, Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Zu Yuangang, E-mail: nefunano@yahoo.com.cn [Key Laboratory of Forest Plant Ecology of Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Engineering Research Center of Forest Bio-preparation, Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Fu Yujie; Zhao Chunjian; Zhao Xiuhua; Meng Ronghua; Tan Shengnan [Key Laboratory of Forest Plant Ecology of Ministry of Education, Northeast Forestry University, Harbin 150040 (China); Engineering Research Center of Forest Bio-preparation, Ministry of Education, Northeast Forestry University, Harbin 150040 (China)

2010-04-01

Camptothecin-loaded gold nanomaterials have been synthesized by the sodium borohydride reduction method under a strong basic condition. The obtained gold nanomaterials have been characterized by transmission electron microscopy (TEM), atomic force microscopy (AFM) and UV-vis absorption spectroscopy. The camptothecin-loaded gold colloidal solution was very stable and can be stored for more than two months at room temperature without obvious changes. The color of the colloidal solution can change from wine red to purple and blue during the acidifying process. It was revealed that the release of camptothecin and the aggregation of gold nanoparticles can be controlled by tuning the solution pH. The present study implied that the gold nanomaterials can be used as the potential carrier for CPT delivery.
Albumin-gold-glutathione is a probable auranofin metabolite

International Nuclear Information System (INIS)

Shaw, C.F. III; Coffer, M.; Isab, A.A.

1989-01-01

The newly licensed gold drug, auranofin ((2,3,4,6-tetra-O-acetyl-β-1-D-gluco-pyranosato-S-)triethylphoshine-gold(I)) crosses cell membranes and enters cells which are inaccessible to parenteral gold drugs. In vivo, the triethylphosphine ligand and gold of auranofin, but not the thio-sugar moiety, accumulate in and subsequently efflux from red blood cells (RBCs). Extracellular albumin increases in the extent of gold efflux and acts as a gold binding site. The rate of efflux is first-order in RBC gold concentration. Studies using RBCs in which labelled [ 14 C]-glutathione is generated in situ incorporation of [ 14 C]- glycine demonstrate that glutathione also effluxes from the RBCs and forms a gold-glutathione-albumin complex. This may be the immunopharmacologically active complex
Potassium evaluation in blood of Brazilian athletes using NAA

International Nuclear Information System (INIS)

Kovacs, L.; Zamboni, C.B.; Nunes, L.A.S.; Lourenco, T.F.; Macedo, D. Vaz de

2010-01-01

Full text: According to nutrition sources an athlete needs per day at least one gram of potassium for keeping the correct mineral balance in the organism. Its deficiency or even instantaneous low concentration in blood can diminish the athlete performance originating nervous irritability, muscular weakness, and mental disorientation and in more several causes cardiac arrhythmias. In this study the K levels in blood were determined in athletes submitted to constant load exercise at treadmill at LABEX (Laboratorio de Bioquimica do Exercicio - UNICAMP, Brazil) using Neutron Activation Analyses (NAA). The blood samples were collected from male athletes, age 18 to 26 years, before and after the physical training. Immediately after the collection an amount of 10 micro liters of whole blood was transferred to the filter paper and dried for a few minutes using an infrared lamp. To determine the concentration of potassium each sample was irradiated in the nuclear reactor (IEA-R1, 2-4MW, pool type) at IPEN and was gamma counted using an HPGe Spectrometer of High Energy Resolution. The concentrations of the selected element, 1525keV related to the potassium activated 42 K, were calculated using in -house software. The potassium levels were evaluated before and after the physical exercise and the data were compared with the normal range. (author)
Potassium urinary excretion and dietary intake: a cross-sectional analysis in 8-10 year-old children.

Science.gov (United States)

Oliveira, Ana Catarina; Padrão, Patrícia; Moreira, André; Pinto, Mariana; Neto, Mafalda; Santos, Tânia; Madureira, Joana; Fernandes, Eduardo de Oliveira; Graça, Pedro; Breda, João; Moreira, Pedro

2015-05-17

Data from studies assessing the intake of potassium, and the concomitant sodium-to-potassium ratio are limited. The aim of this study was to evaluate potassium and sodium-to-potassium ratio intake in 8-10 year-old children. A cross-sectional survey was carried out from January to June 2014 and data from 163 children (81 boys) were included. Potassium intake was estimated by 24-h urine collection and coefficient of creatinine was used to validate completeness of urine collections. Urinary sodium and sodium-to-potassium ratio were also analysed. A 24-h dietary recall was used to provide information on dietary sources of potassium. Height and weight were measured according to international standards. The mean urinary potassium excretion was 1701 ± 594 mg/day in boys, and 1682 ± 541 mg/day in girls (p = 0.835); 8.0% of children met the WHO recommendations for potassium intake. The mean sodium excretion was 2935 ± 1075 mg/day in boys and 2381 ± 1045 mg/day in girls (p <0.001) and urinary sodium-to-potassium ratio was 3.2 ± 1.4 in boys, and 2.5 ± 1.1 in girls (p = 0.002). The mean fruit and vegetable intake was 353.1 ± 232.5 g/day in boys, and 290.8 ± 213.1 g/day in girls (p = 0.101). This study reported a low compliance of potassium intake recommendations in 8-10 year-old children. Health promotion interventions are needed in order to broaden public awareness of potassium inadequacy and to increase potassium intake.
Development and manufacturing cycle for potassium nitrate and phosphate producing by conversion method

Directory of Open Access Journals (Sweden)

А. И. Алексеев

2016-11-01

Full Text Available Analysis of the Russian market of potash mineral fertilizers in 2014 and forecast for 2015-2019 show [http://businesstat.ru/images/demo/potash_fertilizers_russia.pdf] that today the most widespread potash fertilizer is the potassium chloride. But chloride-free potassium-containing products are in the highest demand at the fertilizer market. One of possible solutions to this problem is recrystallization of the potassium chloride or potassium-containing mineral ores using nitrate-containing or phosphorus-containing salt products. The basis for justifying processing conditions for polymineral potassium-containing salt raw materials and salt mineral ores is the data on phase equilibria in multicomponent water-salt systems. Knowledge of the regularities of phase equilibria in multicomponent salt systems helps to develop optimal conditions for complex processing of polymineral natural and technical raw materials. Below it is present the results of technological calculations for processing potash mineral raw materials with account of the complex nature of its utilization. Based on the analysis of the solubility diagrams of mutual salt systems different cyclic processes for production of potassium dihydrogen phosphate and nitrate and sodium chloride from dihydrogen phosphate and sodium nitrate and potassium chloride by conversion method have been designed, and ways of these processes optimization have been proposed for reducing the cost of certain technical operations.
Potassium and zinc increase tolerance to salt stress in wheat (Triticum aestivum L.).

Science.gov (United States)

Jan, Amin Ullah; Hadi, Fazal; Midrarullah; Nawaz, Muhammad Asif; Rahman, Khaista

2017-07-01

Potassium and zinc are essential elements in plant growth and metabolism and plays a vital role in salt stress tolerance. To investigate the physiological mechanism of salt stress tolerance, a pot experiment was conducted. Potassium and zinc significantly minimize the oxidative stress and increase root, shoot and spike length in wheat varieties. Fresh and dry biomass were significantly increased by potassium followed by zinc as compared to control C. The photosynthetic pigment and osmolyte regulator (proline, total phenolic, and total carbohydrate) were significantly enhanced by potassium and zinc. Salt stress increases MDA content in wheat varieties while potassium and zinc counteract the adverse effect of salinity and significantly increased membrane stability index. Salt stress decreases the activities of antioxidant enzymes (superoxide dismutase, catalase and ascorbate peroxidase) while the exogenous application of potassium and zinc significantly enhanced the activities of these enzymes. A significant positive correlation was found of spike length with proline (R 2 = 0.966 ∗∗∗ ), phenolic (R 2 = 0.741 ∗ ) and chlorophyll (R 2 = 0.853 ∗∗ ). The MDA content showed significant negative correlation (R 2 = 0.983 ∗∗∗ ) with MSI. It is concluded that potassium and zinc reduced toxic effect of salinity while its combine application showed synergetic effect and significantly enhanced salt tolerance. Copyright © 2017 Elsevier Masson SAS. All rights reserved.
201Tl heart studies

International Nuclear Information System (INIS)

Bell, R.L.

1976-01-01

At the annual meeting of the Society of Nuclear Medicine there was a preponderance of papers dealing with the heart. The most impressive papers detailed the use of monovalent cation 201 Tl in the evaluation of coronary artery disease. Thallium-201 behaves like potassium in that it enters heart muscle quickly and persists in that organ for several hours. It is unlike most radioactive potassium analogues used for heart studies in that: (1) its gamma energy peaks (69 keV and 80 keV) are more easily collimated with resultant image improvement, (2) its physical half life of 72 hours is sufficiently short to attain high counting rates without too much radiation and is sufficiently long so that storage is not prohibitive, (3) its short half life and lack of Beta radiation results in lower radiation to the patient, and (4) its uptake in heart is greater and uptake in liver and stomach less than other potassium analogues
Preparation of potassium tantalum fluoride from tantalum hydroxide

International Nuclear Information System (INIS)

Silva, F.T. da; Espinola, A.; Dutra, A.J.B.

1987-01-01

Potassium tantalum fluoride (K 2 TaF 7 ) is an intermediary product in the processing of tantaliferous materials; it is the basic raw material for both reduction processes in use presently: reduction by metallic sodium and electrolysis in molten halides. It is normally obtained from a fluorotantalic acid solution to which potassium ions are added the precipitation of white acicular crystals of K 2 TaF 7 . The conditions for precipitation and recrystallization were studied, and crystal characterization were done by scanning electron microscopy, X-ray diffraction and thermogravimetric and thermodifferential analyses. (Author) [pt
Immobilization of gold nanoparticles on cell culture surfaces for safe and enhanced gold nanoparticle-mediated laser transfection

Science.gov (United States)

Kalies, Stefan; Heinemann, Dag; Schomaker, Markus; Gentemann, Lara; Meyer, Heiko; Ripken, Tammo

2014-01-01

Abstract. In comparison to standard transfection methods, gold nanoparticle-mediated laser transfection has proven to be a versatile alternative. This is based on its minor influence on cell viability and its high efficiency, especially for the delivery of small molecules like small interfering RNA. However, in order to transfer it to routine usage, a safety aspect is of major concern: The avoidance of nanoparticle uptake by the cells is desired. The immobilization of the gold nanoparticles on cell culture surfaces can address this issue. In this study, we achieved this by silanization of the appropriate surfaces and the binding of gold nanoparticles to them. Comparable perforation efficiencies to the previous approaches of gold nanoparticle-mediated laser transfection with free gold nanoparticles are demonstrated. The uptake of the immobilized particles by the cells is unlikely. Consequently, these investigations offer the possibility of bringing gold nanoparticle-mediated laser transfection closer to routine usage. PMID:25069006
Sodium and potassium concentrations in floral nectars in relation to ...

African Journals Online (AJOL)

Sodium and potassium concentrations have been measured in nectar from a variety of flowering plants visited by honey bees (Apis mellifera capensis). In 18 plant species the mean sodium concentration was 9,8 ± 1,4 mmol (± S.E.), and the mean potassium concentration was 18,7 ± 4,3 mmol. These results are compared ...
High temperature creep of single crystals of gold, silver and solid solution gold silver 50-50

International Nuclear Information System (INIS)

Dorizzi, Paul

1973-01-01

We have studied in compression creep along a direction, single crystals of gold, silver and a 50-50 gold-silver solid solution. The experiments were made at temperatures above 0.7 Tf. We have shown that under these conditions and for these three metals a new slip system is operating: the deformation is due to the slip of dislocations having a 1/2 burgers vector on the {110} planes. For gold the activation energy for creep is equal to the self-diffusion energy. We found the same result for silver when the contribution of divacancies to the self-diffusion energy is taken into account. For the alloy the activation energy for creep is very close to the self-diffusion energy of gold in a 50-50 gold-silver alloy, gold being the slower diffusing species in the alloy. The curves giving the creep rate versus the stress can be fitted with the following laws: ε 0 = σ 5 for gold; ε 0 = σ 2,2 for silver and ε 0 = σ 2,5 for the alloy. The dislocation substructure was studied using the crystalline contrast given by the electron microprobe. This new method gives images which are very sensitive to the sub-grains misorientation. The substructure is made of parallelepipedic cells divided by tilt boundaries that are perpendicular to the {110} slip planes. (author) [fr
Gold - Old Drug with New Potentials.

Science.gov (United States)

Faa, Gavino; Gerosa, Clara; Fanni, Daniela; Lachowicz, Joanna I; Nurchi, Valeria M

2018-01-01

Research into gold-based drugs for a range of human diseases has seen a revival in recent years. This article reviews the most important applications of gold products in different fields of human pathology. Au(I) and Au(III) compounds have been re-introduced in clinical practice for targeting the cellular components involved in the onset and progression of viral and parasitic diseases, rheumatoid arthritis and cancer. After some brief historical notes, this article takes into account the applications of gold compounds against Mycobacterium tuberculosis, and also in tuberculosis and in rheumatoid arthritis treatment. The use of gold containing drugs in the cure of cancer are then considered, with special emphasis to the use of nanoparticles and to the photo-thermal cancer therapy. The use of colloidal gold in diagnostics, introduced in the last decade is widely discussed. As a last point a survey on the adverse effects and on the toxicity of the various gold derivatives in use in medicine is presented. In this review, we described the surprisingly broad spectrum of possible uses of gold in diagnostics and in therapeutic approaches to multiple human diseases, ranging from degenerative to infectious diseases, and to cancer. In particular, gold nanoparticles appear as attractive elements in modern clinical medicine, combining high therapeutic properties, high selectivity in targeting cancer cells and low toxicity. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.
Red gold analysis by using gamma absorption tchnique

International Nuclear Information System (INIS)

Kurtoglu, A.; Tugrul, A.B.

2001-01-01

Gold is a valuable metal and also preferable materials for antique artefacts and some advanced technology products. It can be offered for the analysis of the gold as namely; neutron activation analysis, X-ray florescence technique, Auger spectroscopy, atomic absorption and wet chemistry. Some limitations exist in practice for these techniques, especially in the points of financial and applicability concepts. An advanced a practical technique is gamma absorption technique for the gold alloys. This technique is based on discontinuities in the absorption coefficient for gamma rays at corresponding to the electronic binding energies of the absorber. If irradiation is occurred at gamma absorption energy for gold, absorption rates of the red gold changes via the gold amounts in the alloy. Red gold is a basic and generally preferable alloy that has copper and silver additional of the gold in it. The gold amount defines as carat of the gold. Experimental studies were observed for four different carats of red gold; these are 8, 14, 18 and 22 carats. K-edge energy level of the gold is on 80 keV energy. So, Ba-133 radioisotope is preferred as the gamma source because of it has gamma energy peak in that energy. Experiments observed in the same geometry for all samples. NaI(Tl) detector and multichannel analyser were used for measurements. As a result of the experiments, the calibration curves could be drawn for red gold. For examine this curve, unknown samples are measured in experimental set and it can be determined the carat of it with the acceptability. So the red gold analysis can be observed non-destructively, easily and quickly by using the gamma absorption technique
Degradation behaviour of potassium K-phosphite in apple trees

OpenAIRE

Kelderer, Markus; Matteazzi, Aldo; Casera, Claudio

2008-01-01

Although potassium phosphite is not registered for organic fruit production in Europe, it has long been regarded as a potential alternative to sulphur- and copper-containing fungicides. In 2005/2006 a field trial was carried out to verify the presence of residues of phosphoric acid over time in apples after applications of potassium phosphite at different time-points. No residues were present on fruits if treatments were applied before flowering, whereas treatments after flower...
GOLD-BEARING MINERALIZED ZONES OF THE YUZHNOE ORE OCCURRENCE AND ITS COMPARISON WITH LODE GOLD DEPOSITS OF YENISEI RIDGE

OpenAIRE

MANSUROV R.KH.

2016-01-01

The relevance of the discussed issue is caused by the need to detect a new gold ore deposits within the Yenisei ridge to replenish the mineral resources of gold ore in Russia. The main aim of the study is to explore the features of geological structure and gold ore mineralized zones of ore occurrence Yuzhnoe in order to forecast gold ore bodies, and to substantiate the continuation of geological exploration. The prospecting is realized by the express method of prospecting of gold ore deposits...
Diazonium-derived aryl films on gold nanoparticles: evidence for a carbon-gold covalent bond.

Science.gov (United States)

Laurentius, Lars; Stoyanov, Stanislav R; Gusarov, Sergey; Kovalenko, Andriy; Du, Rongbing; Lopinski, Gregory P; McDermott, Mark T

2011-05-24

Tailoring the surface chemistry of metallic nanoparticles is generally a key step for their use in a wide range of applications. There are few examples of organic films covalently bound to metal nanoparticles. We demonstrate here that aryl films are formed on gold nanoparticles from the spontaneous reduction of diazonium salts. The structure and the bonding of the film is probed with surface-enhanced Raman scattering (SERS). Extinction spectroscopy and SERS show that a nitrobenzene film forms on gold nanoparticles from the corresponding diazonium salt. Comparison of the SERS spectrum with spectra computed from density functional theory models reveals a band characteristic of a Au-C stretch. The observation of this stretch is direct evidence of a covalent bond. A similar band is observed in high-resolution electron energy loss spectra of nitrobenzene layers on planar gold. The bonding of these types of films through a covalent interaction on gold is consistent with their enhanced stability observed in other studies. These findings provide motivation for the use of diazonium-derived films on gold and other metals in applications where high stability and/or strong adsorbate-substrate coupling are required.
Improvement of Gold Leaching from a Refractory Gold Concentrate Calcine by Separate Pretreatment of Coarse and Fine Size Fractions

Directory of Open Access Journals (Sweden)

Qian Li

2017-05-01

Full Text Available A total gold extraction of 70.2% could only be reached via direct cyanidation from a refractory As-, S- and C-bearing gold concentrate calcine, and the gold extraction varied noticeably with different size fractions. The reasons for unsatisfactory gold extraction from the calcine were studied through analyses of chemical composition, chemical phase and SEM-EDS of different sizes of particles. It was found that a significant segregation of compositions occurred during the grinding of gold ore before flotation. As a result, for the calcine obtained after oxidative roasting, the encapsulation of gold by iron oxides was easily engendered in finer particles, whilst in coarser particles the gold encapsulation by silicates was inclined to occur likely due to melted silicates blocking the porosity of particles. The improvement of gold leaching from different size fractions was further investigated through pretreatments with alkali washing, acid pickling or sulfuric acid curing-water leaching. Finally, a novel process was recommended and the total gold extraction from the calcine could be increased substantially to 93.6% by the purposeful pretreatment with alkali washing for the relatively coarse size fraction (+37 μm and sulfuric acid curing–water leaching for the fine size fraction (−37 μm.
GENETIC DIVERSITY IN ARABICA COFFEE GROWN IN POTASSIUM-CONSTRAINED ENVIRONMENT

Directory of Open Access Journals (Sweden)

Waldênia de Melo Moura

2015-02-01

Full Text Available Potassium is a source of non-renewable natural resource, and is used in large quantities in coffee fertilization through basically imported formulations in the form of potassium chloride. An alternative to make production systems more sustainable would be obtaining cultivars more efficient in the use of this nutrient. This study aimed to evaluate the genetic diversity among 20 cultivars of coffee, in conditions of low availability of potassium to identify the best combinations for composing future populations to be used in breeding programs. The experiment was arranged in a randomized block design with three replications of nutrient solution. Agronomic characteristics and efficiencies of rooting, absorption, translocation, biomass production and potassium utilization were evaluated. The clustering analysis was based on the unweighted pair group method with arithmetic mean clustering algorithm (UPGMA and canonical variables. Variability was observed for most treatments. The multivariate procedures produced similar discrimination of genotypes, with the formation of five groups. Hybridizations between the cultivar Icatu Precoce IAC 3283 with cultivars Catuaí Amarelo IAC 62, Araponga MG1, Caturra Vermelho IAC 477, Catuaí Vermelho IAC 15, Rubi MG 1192 and Catucaí 785/15, and between the cultivar Tupi IAC 1669-33 with cultivars Icatu Vermelho IAC 4045, Acaiá Cerrado MG 1474 and Oeiras MG 6851 are the most promising for obtaining segregating populations or heterotic hybrids in breeding programs aiming more efficiency in potassium utilization.
Soil salinity and yield of mango fertigated with potassium sources

Directory of Open Access Journals (Sweden)

Marcio A. Carneiro

Full Text Available ABSTRACT Irrigated fruit crops have an important role in the economic and social aspects in the region of the Sub-middle São Francisco River Valley. Thus, the aim of this study was to evaluate soil salinity and the productive aspects of the mango crop, cv. Tommy Atkins, fertigated with doses of potassium chloride (KCl and potassium sulfate (K2SO4 during two crop cycles (from January to March 2014 and from January to March 2015. The experiment was carried out in a strip-split-plot design and five potassium doses (50, 75, 100, 125 and 150% of the recommended dose as plots and two potassium sources (KCl and K2SO4 as subplots, with four replicates. Soil electrical conductivity (EC, exchangeable sodium (Na+ and potassium (K+ contents and pH were evaluated. In addition, the number of commercial fruits and yield were determined. The fertilization with KCl resulted in higher soil EC compared with K2SO4 fertigation. Soil Na+ and K+ contents increased with increasing doses of fertilizers. K2SO4 was more efficient for the production per plant and yield than KCl. Thus, under the conditions of this study, the K2SO4 dose of 174.24 g plant-1 (24.89 kg ha-1 or 96.8% of recommendation, spacing of 10 x 7 m was recommended for a yield of 23.1 t ha-1 of mango fruits, cv. Tommy Atkins.
21 CFR 73.1125 - Potassium sodium copper chloropyhllin (chlorophyllin-copper complex).

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Potassium sodium copper chloropyhllin (chlorophyllin-copper complex). 73.1125 Section 73.1125 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT....1125 Potassium sodium copper chloropyhllin (chlorophyllin-copper complex). (a) Identity. (1) The color...

21 CFR 73.2125 - Potassium sodium copper chlorophyllin (chlorophyllin-copper complex).

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Potassium sodium copper chlorophyllin (chlorophyllin-copper complex). 73.2125 Section 73.2125 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT... § 73.2125 Potassium sodium copper chlorophyllin (chlorophyllin-copper complex). (a) Identity and...
Crystal structure transformation in potassium acrylate

Science.gov (United States)

Pai Verneker, V. R.; Vasanthakumari, R.

1983-10-01

Potassium acrylate undergoes a reversible phase transformation around 335°K with an activation energy of 133 kcal/mole. Differential scanning calorimetry and high temperature X-ray powder diffraction techniques have been used to probe this phenomenon.
New insights into the extraction of invisible gold in a low-grade high-sulfur Carlin-type gold concentrate by bio-pretreatment

Science.gov (United States)

Qiu, Xiao-bin; Wen, Jian-kang; Huang, Song-tao; Yang, Hong-ying; Liu, Mei-lin; Wu, Biao

2017-10-01

To extract gold from a low-grade (13.43 g/t) and high-sulfur (39.94wt% sulfide sulfur) Carlin-type gold concentrate from the Nibao deposit, Guizhou, a bio-pretreatment followed by carbon-in-pulp (CIP) cyanide leaching process was used. Various methods were used to detect the low-grade gold in the concentrate; however, only time-of-flight secondary-ion mass spectrometry (TOF-SIMS) was successful. With bio-pretreatment, the gold recovery rate increased by approximately 70.16% compared with that obtained by direct cyanide leaching of the concentrate. Various attempts were made to increase the final gold recovery rate. However, approximately 20wt% of the gold was non-extractable. To determine the nature of this non-extractable gold, mineralogy liberation analysis (MLA), formation of secondary product during the bio-pretreatment, and the preg-robbing capacity of the carbonaceous matter in the ore were investigated. The results indicated that at least four factors affected the gold recovery rate: gold occurrence, tight junctions of gold-bearing pyrite with gangue minerals, jarosite coating of the ore, and the carbonaceous matter content.
NUCLEATION STUDIES OF GOLD ON CARBON ELECTRODES

Directory of Open Access Journals (Sweden)

S. SOBRI

2008-04-01

Full Text Available Interest has grown in developing non-toxic electrolytes for gold electrodeposition to replace the conventional cyanide-based bath for long term sustainability of gold electroplating. A solution containing thiosulphate and sulphite has been developed specially for microelectronics applications. However, at the end of the electrodeposition process, the spent electrolyte can contain a significant amount of gold in solution. This study has been initiated to investigate the feasibility of gold recovery from a spent thiosulphate-sulphite electrolyte. We have used flat-plate glassy carbon and graphite electrodes to study the mechanism of nucleation and crystal growth of gold deposition from the spent electrolyte. It was found that at the early stages of reduction process, the deposition of gold on glassy carbon exhibits an instantaneous nucleation of non-overlapping particles. At longer times, the particles begin to overlap and the deposition follows a classic progressive nucleation phenomenon. On the other hand, deposition of gold on graphite does not follow the classical nucleation phenomena.
BROOKHAVEN: High energy gold

International Nuclear Information System (INIS)

Bleser, Ed

1992-01-01

On April 24, Brookhaven's Alternating Gradient Synchrotron (AGS) started to deliver gold ions at 11.4 GeV per nucleon (2,000 GeV per ion) to experimenters who were delighted not only to receive the world's highest energy gold beam but also to receive it on schedule
Structurally diverse natural products that cause potassium leakage trigger multicellularity in Bacillus subtilis.

Science.gov (United States)

López, Daniel; Fischbach, Michael A; Chu, Frances; Losick, Richard; Kolter, Roberto

2009-01-06

We report a previously undescribed quorum-sensing mechanism for triggering multicellularity in Bacillus subtilis. B. subtilis forms communities of cells known as biofilms in response to an unknown signal. We discovered that biofilm formation is stimulated by a variety of small molecules produced by bacteria--including the B. subtilis nonribosomal peptide surfactin--that share the ability to induce potassium leakage. Natural products that do not cause potassium leakage failed to induce multicellularity. Small-molecule-induced multicellularity was prevented by the addition of potassium, but not sodium or lithium. Evidence is presented that potassium leakage stimulates the activity of a membrane protein kinase, KinC, which governs the expression of genes involved in biofilm formation. We propose that KinC responds to lowered intracellular potassium concentration and that this is a quorum-sensing mechanism that enables B. subtilis to respond to related and unrelated bacteria.
Sensitive flotation-spectrophotometric determination of gold, based on the gold(I)-iodide-methylene blue system.

Science.gov (United States)

Marczenko, Z; Jankowski, K

1985-04-01

The gold(I)-iodide-Methylene Blue (MB) system is suitable for flotation separation and spectrophotometric determination of gold. Under the optimum conditions [(MB(+))(AuI(2)(-))].3[(MB(+))(I(3)(-))] is formed, and floated with cyclohexane. The product is dissolved in methanol and its absorbance measured. The molar absorptivity is 3.4 x 10(5)1.mole(-1).cm(-1) at 655 nm. The proposed method is more than three times as sensitive as the Rhodamine B method. Pt, Pd, Ag and Hg interfere seriously, and Ir, Rh, Bi and Cd to a smaller extent. Preliminary separation of gold by precipitation with tellurium as a collector is recommended. The method has been applied to determination of gold traces (about 1 x 10(-4)%) in a copper sample.
Thanatochemistry: Study of vitreous humor potassium

African Journals Online (AJOL)

Nilesh Keshav Tumram

2014-02-18

Feb 18, 2014 ... particularly vitreous potassium has received most attention. It is known that ... respect to different age and sex at different death intervals. The details regarding the ... Analyser by the Ion selective method. The reagents used ...
Scanning Tunneling Spectroscopy of Potassium on Graphene

Science.gov (United States)

Cormode, Daniel; Leroy, Brian; Yankowitz, Matthew

2012-02-01

We investigate the effect of charged impurities on the electronic properties of large single crystal CVD grown graphene using scanning tunneling microscopy. Mono- and multilayer crystals were prepared by transferring graphene from copper onto exfoliated boron nitride flakes on 300 nm SiO2 substrates. The boron nitride provides an ultra flat surface for the graphene. Potassium atoms are controllably deposited on the graphene at low temperature by heating a nearby getter source. Scanning tunneling spectroscopy and transport measurements were performed in ultra high vacuum at 4.5 K. Transport measurements demonstrate the shifting of the Dirac point as the samples are doped, while STM measurements demonstrate the size, arrangement and local electronic influence of the potassium atoms.
Slack, Slick, and Sodium-Activated Potassium Channels

Science.gov (United States)

Kaczmarek, Leonard K.

2013-01-01

The Slack and Slick genes encode potassium channels that are very widely expressed in the central nervous system. These channels are activated by elevations in intracellular sodium, such as those that occur during trains of one or more action potentials, or following activation of nonselective cationic neurotransmitter receptors such as AMPA receptors. This review covers the cellular and molecular properties of Slack and Slick channels and compares them with findings on the properties of sodium-activated potassium currents (termed KNa currents) in native neurons. Human mutations in Slack channels produce extremely severe defects in learning and development, suggesting that KNa channels play a central role in neuronal plasticity and intellectual function. PMID:24319675
Efficacy and safety of topical application of 15% and 10% potassium hydroxide for the treatment of Molluscum contagiosum.

Science.gov (United States)

Teixidó, Concepció; Díez, Olga; Marsal, Josep R; Giner-Soriano, Maria; Pera, Helena; Martinez, Mireia; Galindo-Ortego, Gisela; Schoenenberger, Joan A; Real, Jordi; Cruz, Ines; Morros, Rosa

2018-02-26

Molluscum contagiosum is the most common skin infection in children. One topical treatment used for Molluscum contagiosum is potassium hydroxide. The objective of this study was to compare the efficacy of potassium hydroxide topical treatment at different concentrations with that of placebo in terms of complete clearing of Molluscum contagiosum lesions and to assess the safety and tolerance of potassium hydroxide topical treatment. This was a double-blind randomized clinical trial of three treatments (potassium hydroxide 10%, potassium hydroxide 15%, placebo) applied once daily up to complete clearing of lesions (maximum duration 60 days) in 53 children aged 2-6 years in primary health care pediatric offices in Catalonia, Spain. In the intention-to-treat analysis, potassium hydroxide 10% (58.8%, P = .03) and potassium hydroxide 15% (64.3%, P = .02) had efficacy superior to that of placebo (18.8%). The number of Molluscum contagiosum lesions was significantly reduced with potassium hydroxide 10% and 15%. The main efficacy outcome was achieved in 58.8% of children in the potassium hydroxide 10% group (P = .03 vs placebo) and in 64.3% of children in the potassium hydroxide 15% group (P = .02 vs placebo). Potassium hydroxide 10% and 15% were not significantly different in efficacy from each other. Potassium hydroxide 10% and placebo were better tolerated than potassium hydroxide 15%. No adverse events were reported during the study period. Potassium hydroxide 10% and 15% demonstrated high rates of efficacy in clearing Molluscum contagiosum lesions, with potassium hydroxide 10% being better tolerated. © 2018 Wiley Periodicals, Inc.
Potassium tetracyanidoaurate(III monohydrate: a redetermination

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Nobuyuki Matsushita

2017-03-01

Full Text Available The structure of the title metal complex salt, K[Au(CN4]·H2O, has been redetermined using X-ray diffraction data at 173 K in order to improve the precision. The previous determination was based on neutron diffraction data [Bertinotti & Bertinotti (1970. Acta Cryst. B26, 422–428]. The title compound crystallizes in the space group P212121 with one potassium cation, one [Au(CN4]− anion and one water molecule in the asymmetric unit. The AuIII atom lies on a general position and has an almost square-planar coordination sphere defined by four cyanide ligands. Interactions between the potassium cation and N atoms of the complex anion, as well as O—H...N hydrogen bonds, lead to the formation of a three-dimensional framework structure.
Nutritional and taste characteristics of low-potassium lettuce developed for patients with chronic kidney diseases

OpenAIRE

Yoshida, Takuya; Sakuma, Kozue; Kumagai, Hiromichi

2014-01-01

Dietary potassium restriction is recommended for chronic kidney disease (CKD) patients with hyperkalemia. Boiling or soaking vegetables in water is known to decrease their potassium content. However, these methods can also reduce the quantity of other nutrients. Recently, low-potassium (LK) lettuce has been developed for CKD patients with hyperkalemia. This study compared the potassium content, other nutritional values, and taste characteristics of LK lettuce with those of normal lettuce. The...
Soil transport parameters of potassium under a tropical saline soil condition using STANMOD

Science.gov (United States)

Suzanye da Silva Santos, Rafaelly; Honorio de Miranda, Jarbas; Previatello da Silva, Livia

2015-04-01

Environmental responsibility and concerning about the final destination of solutes in soil, so more studies allow a better understanding about the solutes behaviour in soil. Potassium is a macronutrient that is required in high concentrations, been an extremely important nutrient for all agricultural crops. It plays essential roles in physiological processes vital for plant growth, from protein synthesis to maintenance of plant water balance, and is available to plants dissolved in soil water while exchangeable K is loosely held on the exchange sites on the surface of clay particles. K will tend to be adsorbed onto the surface of negatively charged soil particles. Potassium uptake is vital for plant growth but in saline soils sodium competes with potassium for uptake across the plasma membrane of plant cells. This can result in high Na+:K+ ratios that reduce plant growth and eventually become toxic. This study aimed to obtain soil transport parameters of potassium in saline soil, such as: pore water velocity in soil (v), retardation factor (R), dispersivity (λ) and dispersion coefficient (D), in a disturbed sandy soil with different concentrations of potassium chlorate solution (KCl), which is one of the most common form of potassium fertilizer. The experiment was carried out using soil samples collected in a depth of 0 to 20 cm, applying potassium chlorate solution containing 28.6, 100, 200 and 500 mg L-1 of K. To obtain transport parameters, the data were adjusted with the software STANMOD. At low concentrations, interaction between potassium and soil occur more efficiently. It was observed that only the breakthrough curve prepared with solution of 500 mg L-1 reached the applied concentration, and the solution of 28.6 mg L-1 overestimated the parameters values. The STANMOD proved to be efficient in obtaining potassium transport parameters; KCl solution to be applied should be greater than 500 mg L-1; solutions with low concentrations tend to overestimate
Precipitation of lamellar gold nanocrystals in molten polymers

International Nuclear Information System (INIS)

Palomba, M.; Carotenuto, G.

2016-01-01

Non-aggregated lamellar gold crystals with regular shape (triangles, squares, pentagons, etc.) have been produced by thermal decomposition of gold chloride (AuCl) molecules in molten amorphous polymers (polystyrene and poly(methyl methacrylate)). Such covalent inorganic gold salt is high soluble into non-polar polymers and it thermally decomposes at temperatures compatible with the polymer thermal stability, producing gold atoms and chlorine radicals. At the end of the gold precipitation process, the polymer matrix resulted chemically modified because of the partial cross-linking process due to the gold atom formation reaction.
Synthesis of radioactive gold nanoparticle in surfactant medium

International Nuclear Information System (INIS)

Swadesh Mandal

2014-01-01

The present study describes the synthesis of radioactive gold nanoparticle in surfactant medium. Proton irradiated stable 197 Au and radioactive 198 Au were simultaneously used for production of radioactive gold nanoparticle. Face centered cubic gold nanoparticles with size of 4-50 nm were found in proton irradiated gold foil. However, the size of nanoparticle varies with pH using both stable and radioactive gold. (author)
Coulomb interaction rules timescales in potassium ion channel tunneling

Science.gov (United States)

De March, N.; Prado, S. D.; Brunnet, L. G.

2018-06-01

Assuming the selectivity filter of KcsA potassium ion channel may exhibit quantum coherence, we extend a previous model by Vaziri and Plenio (2010 New J. Phys. 12 085001) to take into account Coulomb repulsion between potassium ions. We show that typical ion transit timescales are determined by this interaction, which imposes optimal input/output parameter ranges. Also, as observed in other examples of quantum tunneling in biological systems, the addition of moderate noise helps coherent ion transport.
Establishment of gold-quartz standard GQS-1

Science.gov (United States)

Millard, Hugh T.; Marinenko, John; McLane, John E.

1969-01-01

A homogeneous gold-quartz standard, GQS-1, was prepared from a heterogeneous gold-bearing quartz by chemical treatment. The concentration of gold in GQS-1 was determined by both instrumental neutron activation analysis and radioisotope dilution analysis to be 2.61?0.10 parts per million. Analysis of 10 samples of the standard by both instrumental neutron activation analysis and radioisotope dilution analysis failed to reveal heterogeneity within the standard. The precision of the analytical methods, expressed as standard error, was approximately 0.1 part per million. The analytical data were also used to estimate the average size of gold particles. The chemical treatment apparently reduced the average diameter of the gold particles by at least an order of magnitude and increased the concentration of gold grains by a factor of at least 4,000.
Diatom. A potential bio-accumulator of gold

International Nuclear Information System (INIS)

Chakraborty, N.; Pal, R.; Ramaswami, A.; Nayak, D.; Lahiri, S.

2006-01-01

The bioaccumulation of gold in trace concentration by Nitzschia obtusa and Navicula minima, two members of bacillariophyceae, has been studied. It has been observed that Nitzschia obtusa showed better accumulation of gold in acidic pH in comparison to neutral and basic pH. Maximum accumulation was observed with 1 mg x kg -1 or less gold concentration. However, the accumulation by the living cells was reduced when the matrix concentration was higher. Navicula minima, on the other hand, found to be a better accumulator of gold in wide ranges of pH and substrate concentration of the media. It was also inferred that the gold accumulation by diatom was mainly due to adsorption by biosilica (siliceous frustules of dead diatom cells). Accumulated gold was recovered with conc. HNO 3 . (author)
G-protein-coupled inward rectifier potassium current contributes to ventricular repolarization

DEFF Research Database (Denmark)

Liang, Bo; Nissen, Jakob D; Laursen, Morten

2014-01-01

The purpose of this study was to investigate the functional role of G-protein-coupled inward rectifier potassium (GIRK) channels in the cardiac ventricle.......The purpose of this study was to investigate the functional role of G-protein-coupled inward rectifier potassium (GIRK) channels in the cardiac ventricle....

Pancreatitis associated with potassium bromide/phenobarbital combination therapy in epileptic dogs.

OpenAIRE

Gaskill, C L; Cribb, A E

2000-01-01

In a retrospective study, at least 10% of dogs receiving potassium bromide/phenobarbital combination therapy, compared with 0.3% of dogs receiving phenobarbital monotherapy, had probable pancreatitis. Pancreatitis may be a more frequent and more serious adverse effect of potassium bromide/phenobarbital combination therapy than has been reported previously.
Investigations of corrosion phenomena on gold coins with SIMS

International Nuclear Information System (INIS)

Mayerhofer, K.E.; Piplits, K.; Traum, R.; Griesser, M.; Hutter, H.

2005-01-01

In order to establish a new handling procedure for contaminated coins, the Coin Cabinet and the Conservation Science Department of the Kunsthistorisches Museum, Vienna, initiated a research project on corrosion effects of gold coins. By now, investigations on historic and contemporary coins included optical microscopy, scanning electron microscopy (SEM), Auger electron microscopy (AES), X-ray photoelectron microscopy (XPS), and electrochemical methods showing the distribution of pollutants. This work focuses on secondary ion mass spectrometry (SIMS) investigations merely showing the distribution of electronegative elements, such as sulfur, oxygen, and chlorine on the surface. Sulfur is highly suspected of causing the observed corrosion phenomena, and is indeed enriched near polluting splints. Since SIMS is a destructive method, the investigated samples are test coins with intentionally added impurities. These coins were manufactured in cooperation with the Austrian Mint. They were treated with potassium polysulfide (K 2 S x ) for 8 h gaining a rapid corrosion of the surface. SIMS mass spectra, depth profiles, and images were done (a) at non-polluted areas (b) near polluted areas with slight coloring, and (c) directly at polluting stains showing enrichments of sulfur and chlorine. Due to the success of these investigations further studies on historic coins are intended
Precipitation of gold by the reaction of aqueous gold(III)-chloride with cyanobacteria at 25-80 C -- Studied by x-ray absorption spectroscopy

International Nuclear Information System (INIS)

Lengke, M. F.; Ravel, B.; Fleet, M. E.; Wanger, G.; Gordon, R. A.; Southam, G.

2007-01-01

The mechanisms of gold precipitation by the interaction of cyanobacteria (Plectonema boryanum UTEX 485) and gold(III) chloride aqueous solutions (7.6 mmol/L final gold) have been studied at 25, 60, and 80 C, using both laboratory and real-time synchrotron radiation absorption spectroscopy experiments. Addition of aqueous gold(III) chloride to the cyanobacterial culture initially promoted the precipitation of amorphous gold(I) sulfide at the cell walls and finally caused the formation of octahedral (111) platelets (<1 to 6 (micro)m) of gold metal near cell surfaces and in solutions. X-ray absorption spectroscopy results confirmed that the reduction mechanism of gold(III) chloride to elemental gold by cyanobacteria involves the formation of an intermediate Au(I) species, gold(I) sulfide, with sulfur originating from cyanobacterial proteins, presumably cysteine or methionine. Although the bioreduction of gold(III) chloride to gold(I) sulfide was relatively rapid at all temperatures, the reaction rate increased with the increase in temperature. At the completion of the experiments, elemental gold was the major species present at all temperatures
Potassium humate inhibits complement activation and the production of inflammatory cytokines in vitro

Energy Technology Data Exchange (ETDEWEB)

van Rensburg, C.E.J.; Naude, P.J. [University of Pretoria, Pretoria (South Africa)

2009-08-15

The effects of brown coal derived potassium humate on lymphocyte proliferation, cytokine production and complement activation were investigated in vitro. Potassium humate increased lymphocyte proliferation of phytohaemaglutinin A (PHA) and pokeweed mitogen (PWM) stimulated mononuclear lymphocytes (MNL) in vitro from concentrations of 20 to 80 {mu} g/ml, in a dose dependant manner. On the other hand potassium humate, at 40 {mu} g/ml, significantly inhibited the release of TNF-alpha, IL-1 beta, IL-6 and IL-10 by PHA stimulated MNL. Regarding complement activation it was found that potassium humate inhibits the activation of both the alternative and classical pathways without affecting the stability of the red blood cell membranes. These results indicate that the anti-inflammatory potential of potassium humate could be partially due to the inhibition of pro-inflammatory cytokines responsible for the initiation of these reactions as well as inhibition of complement activation. The increased lymphocyte proliferation observed, might be due to increased IL-2 production as previously been documented.
Effects of water soaking and/or sodium polystyrene sulfonate addition on potassium content of foods

OpenAIRE

Picq, Christian; Asplanato, M.; Bernillon, N.; Fabre, C.; Roubeix, M.; Ricort, J. M.

2014-01-01

In this study, we determined, by atomic absorption spectrophotometry, the potassium amount leached by soaking or boiling foods identified by children suffering from chronic renal failure as "pleasure food'' and that they cannot eat because of their low-potassium diet, and evaluated whether addition of sodium polystyrene sulfonate resin (i.e. Kayexalate (R)) during soaking or boiling modulated potassium loss. A significant amount of potassium content was removed by soaking (16% for chocolate a...
Performance Evaluation of Refractory Composite Coatings in Potassium Rich Environment

Directory of Open Access Journals (Sweden)

Kristina BRINKIENĖ

2016-09-01

Full Text Available A laboratory scale method was used to study the performance of reinforced cement composites in potassium rich environment of biomass combustion. Buckwheat husk (BH was used as potential source of unexploited biomass product applicable as biomass derived fuel. In order to enhance the alkali effect on the properties of the investigated materials, the solution of potassium carbonate (K2CO3 was selected as potassium rich aggressive environment. Two reinforced cement composites as potential repair coatings for restoration of damaged refractory surfaces with different composition of aggregate were used in corrosion tests. Performance of refractory coatings was evaluated by analysing the microstructure of the treated composites as well as mechanical properties. Energy-dispersive X-ray spectroscopy (SEM/EDS and optical microscopy were used to study the microstructure in the corroded region of the refractory coatings. Long term studies in the solution of 1M K2CO3 for 56 months have demonstrated that composite with the additive of fluid cracking catalyst of oil refinery and petrochemical industries is more durable in the potassium rich environment.DOI: http://dx.doi.org/10.5755/j01.ms.22.3.8348
Effect of osmolarity on potassium transport in isolated cerebral microvessels

International Nuclear Information System (INIS)

Lin, J.D.

1988-01-01

Potassium transport in microvessels isolated from rat brain by a technique involving density gradient centrifugation was studied in HEPES buffer solutions of varying osmolarity from 200 to 420 mosmols, containing different concentration of sodium chloride, choline chloride, or sodium nitrate. The flux of 86 Rb into and out of the endothelial cells was estimated. Potassium influx was very sensitive to the osmolarity of the medium. Ouabain-insensitive K-component was reduced in hypotonic medium and was increased in medium made hypertonic with sodium chloride or mannitol. Choline chloride replacement caused a large reduction in K influx. Potassium influx was significant decrease when nitrate is substituted for chloride ion in isotonic and hypertonic media, whereas a slight decrease was found in hypotonic medium. The decrease of K influx in the ion-replacement medium is due to a decrement of the ouabain-insensitive component. Potassium efflux was unchanged in hypotonic medium but was somewhat reduced in hypertonic medium. The marked effect of medium osmolarity of K fluxes suggests that these fluxes may be responsible for the volume regulatory K movements. The possible mechanism of changes of K flux under anisotonic media is also discussed
Physicochemical Properties of Gold Nanostructures Deposited on Glass

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Zdenka Novotna

2014-01-01

Full Text Available Properties of gold films sputtered onto borosilicate glass substrate were studied. UV-Vis absorption spectra were used to investigate optical parameters. XRD analysis provided information about the gold crystalline nanostructure, the texture, and lattice parameter and biaxial tension was also determined by the XRD method. The surface morphology was examined by atomic force microscopy (AFM; chemical structure of sputtered gold nanostructures was examined by X-ray photoelectron spectroscopy (ARXPS. The gold crystallites are preferentially [111] oriented on the sputtered samples. Gold deposition leads to dramatic changes in the surface morphology in comparison to pristine glass substrate. Oxygen is not incorporated into the gold layer during gold deposition. Experimental data on lattice parameter were also confirmed by theoretical investigations of nanoclusters using tight-binding potentials.
Potassium evaluation in blood of Brazilian athletes using NAA

Energy Technology Data Exchange (ETDEWEB)

Kovacs, L.; Zamboni, C.B. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Nunes, L.A.S.; Lourenco, T.F.; Macedo, D. Vaz de [Universidade Estadual de Campinas (UNICAMP), SP (Brazil)

2010-07-01

Full text: According to nutrition sources an athlete needs per day at least one gram of potassium for keeping the correct mineral balance in the organism. Its deficiency or even instantaneous low concentration in blood can diminish the athlete performance originating nervous irritability, muscular weakness, and mental disorientation and in more several causes cardiac arrhythmias. In this study the K levels in blood were determined in athletes submitted to constant load exercise at treadmill at LABEX (Laboratorio de Bioquimica do Exercicio - UNICAMP, Brazil) using Neutron Activation Analyses (NAA). The blood samples were collected from male athletes, age 18 to 26 years, before and after the physical training. Immediately after the collection an amount of 10 micro liters of whole blood was transferred to the filter paper and dried for a few minutes using an infrared lamp. To determine the concentration of potassium each sample was irradiated in the nuclear reactor (IEA-R1, 2-4MW, pool type) at IPEN and was gamma counted using an HPGe Spectrometer of High Energy Resolution. The concentrations of the selected element, 1525keV related to the potassium activated {sup 42}K, were calculated using in -house software. The potassium levels were evaluated before and after the physical exercise and the data were compared with the normal range. (author)
Regulation of renal Na+-K-ATPase in the rat: role of increased potassium transport

International Nuclear Information System (INIS)

Mujais, S.K.; Chekal, M.A.; Hayslett, J.P.; Katz, A.I.

1986-01-01

The purpose of this study was to characterize the alterations in collecting tubule Na + -K + -ATPase activity produced by sustained increments in dietary potassium in the rat and to evaluate the role of aldosterone in their generation. In adrenal-intact animals, feeding a high-potassium diet or administration of a high physiological dose of aldosterone, which simulates the delivery rate of this hormone during potassium loading, caused marked increments in Na + -K + -ATPase activity in the cortical collecting tubule (CCT) but had no effect on the enzyme in the inner stripe of the medullary collecting tubule (MCT). A significant increase in enzyme activity was also observed after smaller dietary potassium increments and after 4 days of dietary potassium load. In adrenalectomized rats provided with physiological replacement doses of corticosterone and aldosterone, Na + -K + -ATPase activity in both CCT and MCT was similar to that of adrenal-intact controls but remained unchanged after 7 days on the potassium-enriched (10-fold) diet. In contrast, adrenalectomized animals receiving the high physiological dose of aldosterone displayed an increase in Na + -K + -ATPase activity of CCT comparable with that of adrenal-intact animals, whereas the enzyme activity in the MCT was unaffected. In conclusion, 1) following chronic potassium loading Na + -K + -ATPase activity increases significantly in the CCT with no change in its activity in the inner stripe of the MCT; 2) this increase in enzyme activity occurs in a time-dependent fashion and in proportion to the potassium load; and 3) the stimulation of Na + -K + -ATPase activity in adrenal-replaced rats is facilitated by augmented levels of aldosterone, such as those actually observed in adrenal-intact rats subjected to chronic potassium loading
Regulation of renal Na -K-ATPase in the rat: role of increased potassium transport

Energy Technology Data Exchange (ETDEWEB)

Mujais, S.K.; Chekal, M.A.; Hayslett, J.P.; Katz, A.I.

1986-08-01

The purpose of this study was to characterize the alterations in collecting tubule Na -K -ATPase activity produced by sustained increments in dietary potassium in the rat and to evaluate the role of aldosterone in their generation. In adrenal-intact animals, feeding a high-potassium diet or administration of a high physiological dose of aldosterone, which simulates the delivery rate of this hormone during potassium loading, caused marked increments in Na -K -ATPase activity in the cortical collecting tubule (CCT) but had no effect on the enzyme in the inner stripe of the medullary collecting tubule (MCT). A significant increase in enzyme activity was also observed after smaller dietary potassium increments and after 4 days of dietary potassium load. In adrenalectomized rats provided with physiological replacement doses of corticosterone and aldosterone, Na -K -ATPase activity in both CCT and MCT was similar to that of adrenal-intact controls but remained unchanged after 7 days on the potassium-enriched (10-fold) diet. In contrast, adrenalectomized animals receiving the high physiological dose of aldosterone displayed an increase in Na -K -ATPase activity of CCT comparable with that of adrenal-intact animals, whereas the enzyme activity in the MCT was unaffected. In conclusion, 1) following chronic potassium loading Na -K -ATPase activity increases significantly in the CCT with no change in its activity in the inner stripe of the MCT; 2) this increase in enzyme activity occurs in a time-dependent fashion and in proportion to the potassium load; and 3) the stimulation of Na -K -ATPase activity in adrenal-replaced rats is facilitated by augmented levels of aldosterone, such as those actually observed in adrenal-intact rats subjected to chronic potassium loading.
Electroplating of gold using a sulfite-based electrolyte

NARCIS (Netherlands)

Smalbrugge, E.; Jacobs, B.; Falcone, S.; Geluk, E.J.; Karouta, F.; Leijtens, X.J.M.; Besten, den J.H.

2000-01-01

Electroplating of gold is often used in optoelectronic and microelectronic devices for air-bridges, heat-sinks or gold-bumps for flip-chip techniques. The gold-cyanide electrolytes, which are commonly used in gold-electroplating, are toxic and attack resist patterns causing cracks during the plating
Concentration of Potassium in Plasma, Erythrocytes, and Muscle Tissue in Cows with Decreased Feed Intake and Gastrointestinal Ileus.

Science.gov (United States)

Schneider, S; Müller, A; Wittek, T

2016-01-01

Healthy cows consume large amounts of potassium and a sudden loss in appetite can lead to hypokalemia. The routine method to evaluate potassium homeostasis is the measurement of the extracellular potassium in plasma or serum, but this does not provide information about the intracellular potassium pool. To evaluate potassium homeostasis by comparing the extracellular and intracellular potassium concentration in cows with reduced feed intake and gastrointestinal ileus. Twenty cows 1-3 days postpartum (group 1) and 20 cows with gastrointestinal ileus (group 2). Observational cross-sectional study. Plasma potassium was measured by using an ion-sensitive electrode. Intracellular potassium was measured in erythrocytes and muscle tissue (muscle biopsy) by using inductively coupled plasma optical emission spectroscopy. Cows of group 1 did not have hypokalemia. Overall cows with gastrointestinal ileus were hypokalemic (mean ± SD, 2.9 mmol/L ± 0.78), but potassium concentration in erythrocytes and muscle tissue was not lower than in postpartum cows. Intracellular potassium in erythrocytes varied very widely; group 1: 3497-10735 mg/kg (5559 ± 2002 mg/kg), group 2: 4139-21678 mg/kg (7473 ± 4034 mg/kg). Potassium in muscle tissue did not differ between group 1 (3356 ± 735 mg/kg wet weight) and group 2 (3407 ± 1069 mg/kg wet weight). No association between extracellular and intracellular potassium concentrations was detected. That measurement of plasma potassium concentration is not sufficient to evaluate potassium metabolism of cows. Copyright © 2016 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.
Inhibition of large conductance calcium-dependent potassium ...

African Journals Online (AJOL)

conductance, calcium and voltage- dependent potassium (BKCa) channels thereby promoting vasoconstriction. Our results show that the Rho-kinase inhibitor, Y-27632, induced concentration-dependent relaxation in rat mesenteric artery.
Urban artisanal gold shops and mercury emissions

International Nuclear Information System (INIS)

Cordy, P.; Veiga, M.; Carrasco, V.H.G.

2008-01-01

Artisanal miners in developing countries use mercury amalgamation processes to extract gold. The amalgams are then refined before being sold on to urban gold shops. The amalgams can often contain between 2 to 40 per cent mercury. Unburned amalgams are also often sold directly to gold shops. There are serious health risks for shop employees and nearby populations when the gold is melted and further purified. Studies have shown that mercury concentrations in the ambient air of gold shops often exceeds World Health Organization (WHO) limits by an order of magnitude or more. This study examined the practices and technologies used to refine gold in Latin America and Indonesia. The study compared and contrasted various refining methods and their resulting mercury emissions. Methods of reducing mercury emissions were also investigated, including a filtration system designed to capture 80 per cent of mercury emissions. Barriers to implementing mercury emissions reduction plans were also investigated. It was concluded that the design of urban gold shops must include condensers, fume hoods, and efficient mercury capture systems. 15 refs
Sodium-Reduced Meat and Poultry Products Contain a Significant Amount of Potassium from Food Additives.

Science.gov (United States)

Parpia, Arti Sharma; Goldstein, Marc B; Arcand, JoAnne; Cho, France; L'Abbé, Mary R; Darling, Pauline B

2018-05-01

Sodium-reduced packaged food products are increasingly available to consumers; however, it is not clear whether they are suitable for inclusion in a potassium-reduced diet. For individuals with impaired renal potassium excretion caused by chronic kidney disease and for those taking certain medications that interfere with the rennin-angiotensin aldosterone axis, the need to limit dietary potassium is important in view of the risk for development of hyperkalemia and fatal cardiac arrhythmias. The primary objective of this study was to determine the impact of the reduction of sodium in packaged meat and poultry products (MPPs) on the content of potassium and phosphorus from food additives. This was a cross-sectional study comparing chemically analyzed MPPs (n=38, n=19 original, n=19 sodium-reduced), selected from the top three grocery chains in Canada, based on market share sales. All MPPs with a package label containing a reduced sodium content claim together with their non-sodium-reduced packaged MPP counterparts were selected for analysis. The protein, sodium, phosphorus, and potassium contents of sodium-reduced MPPs and the non-sodium-reduced (original) MPP counterparts were chemically analyzed according to the Association of Analytical Communities official methods 992.15 and 984.27 and compared by using a paired t test. The frequency of phosphorus and potassium additives appearing on the product labels' ingredient lists were compared between groups by using McNemar's test. Sodium-reduced MPPs (n=19) contained 44% more potassium (mg/100 g) than their non-sodium-reduced counterparts (n=19) (mean difference [95% CI): 184 [90-279]; P=0.001). The potassium content of sodium-reduced MPPs varied widely and ranged from 210 to 1,500 mg/100 g. Potassium-containing additives were found on the ingredient list in 63% of the sodium-reduced products and 26% of the non-sodium-reduced products (P=0.02). Sodium-reduced MPPs contained 38% less sodium (mg/100 g) than their non
Potassium as an intrinsic uncoupler of the plasma membrane H+-ATPase

DEFF Research Database (Denmark)

Palmgren, Michael Gjedde; Buch-Pedersen, Morten Jeppe

The plant plasma membrane proton pump (H(+)-ATPase) is stimulated by potassium, but it has remained unclear whether potassium is actually transported by the pump or whether it serves other roles. We now show that K(+) is bound to the proton pump at a site involving Asp(617) in the cytoplasmic...
Gold analysis by the gamma absorption technique

International Nuclear Information System (INIS)

Kurtoglu, Arzu; Tugrul, A.B.

2003-01-01

Gold (Au) analyses are generally performed using destructive techniques. In this study, the Gamma Absorption Technique has been employed for gold analysis. A series of different gold alloys of known gold content were analysed and a calibration curve was obtained. This curve was then used for the analysis of unknown samples. Gold analyses can be made non-destructively, easily and quickly by the gamma absorption technique. The mass attenuation coefficients of the alloys were measured around the K-shell absorption edge of Au. Theoretical mass attenuation coefficient values were obtained using the WinXCom program and comparison of the experimental results with the theoretical values showed generally good and acceptable agreement
Surface vertical deposition for gold nanoparticle film

International Nuclear Information System (INIS)

Diao, J J; Qiu, F S; Chen, G D; Reeves, M E

2003-01-01

In this rapid communication, we present the surface vertical deposition (SVD) method to synthesize the gold nanoparticle films. Under conditions where the surface of the gold nanoparticle suspension descends slowly by evaporation, the gold nanoparticles in the solid-liquid-gas junction of the suspension aggregate together on the substrate by the force of solid and liquid interface. When the surface properties of the substrate and colloidal nanoparticle suspension define for the SVD, the density of gold nanoparticles in the thin film made by SVD only depends on the descending velocity of the suspension surface and on the concentration of the gold nanoparticle suspension. (rapid communication)
[Biosynthesis of gold nanoparticles by Azospirillum brasilense].

Science.gov (United States)

Kupriashina, M A; Vetchinkina, E P; Burov, A M; Ponomareva, E G; Nikitina, V E

2014-01-01

Plant-associated nitrogen-fixing soil bacteria Azospirillum brasilense were shown to reduce the gold of chloroauric acid to elemental gold, resulting in formation of gold nanoparicles. Extracellular phenoloxidizing enzymes (laccases and Mn peroxidases) were shown to participate in reduction of Au+3 (HAuCl4) to Au(0). Transmission electron microscopy revealed accumulation of colloidal gold nanoparticles of diverse shape in the culture liquid of A. brasilense strains Sp245 and Sp7. The size of the electron-dense nanospheres was 5 to 50 nm, and the size of nanoprisms varied from 5 to 300 nm. The tentative mechanism responsible for formation of gold nanoparticles is discussed.

Determination of microamounts of potassium in sodium iodide by atomic absorption spectrometry

International Nuclear Information System (INIS)

Ogasawara, Ken; Ohta, Masatoshi; Abe, Kenzo

1980-01-01

Microdetermination of potassium in sodium iodide was developed by the standard addition method. Twenty grams of sample were dissolved in 50 ml of water in a quartz beaker. To the solution, 30 ml of concentrated hydrochloric acid and 30 ml of 30% hydrogen peroxide were added, and evaporated to dryness. By this process sodium iodide was converted into sodium chloride. The cake thus obtained was dissolved in water and diluted to exactly 200 ml. To 25 ml aliquots of the solution, the standard potassium and cesium chloride solutions were added and diluted to 50 ml with water; the concentration of potassium was 0 -- 1 mg/l and that of cesium 4 mM. These solutions were introduced into an air-propane flame and the absorbances were measured at 769.9 nm. During the conversion reaction, hydrochloric acid was completely decomposed, and remained hydrogen peroxide had no influence for absorbance, and other backgrounds were negligible. The linear calibration curve was obtained in the range 0 -- 2 mg of potassium per liter. Potassium in sodium iodide was determined by this method within the coefficient of variation of +-(20 -- 3)% in the range (1.7 -- 32.5) ppm. (author)
Biomass processing over gold catalysts

CERN Document Server

Simakova, Olga A; Murzin, Dmitry Yu

2014-01-01

The book describes the valorization of biomass-derived compounds over gold catalysts. Since biomass is a rich renewable feedstock for diverse platform molecules, including those currently derived from petroleum, the interest in various transformation routes has become intense. Catalytic conversion of biomass is one of the main approaches to improving the economic viability of biorefineries. In addition, Gold catalysts were found to have outstanding activity and selectivity in many key reactions. This book collects information about transformations of the most promising and important compounds derived from cellulose, hemicelluloses, and woody biomass extractives. Since gold catalysts possess high stability under oxidative conditions, selective oxidation reactions were discussed more thoroughly than other critical reactions such as partial hydrogenation, acetalization, and isomerization. The influence of reaction conditions, the role of the catalyst, and the advantages and disadvantages of using gold are pre...
Optical trapping of gold aerosols

DEFF Research Database (Denmark)

Schmitt, Regina K.; Pedersen, Liselotte Jauffred; Taheri, S. M.

2015-01-01

Aerosol trapping has proven challenging and was only recently demonstrated.1 This was accomplished by utilizing an air chamber designed to have a minimum of turbulence and a laser beam with a minimum of aberration. Individual gold nano-particles with diameters between 80 nm and 200 nm were trapped...... in air using a 1064 nm laser. The positions visited by the trapped gold nano-particle were quantified using a quadrant photo diode placed in the back focal plane. The time traces were analyzed and the trapping stiffness characterizing gold aerosol trapping determined and compared to aerosol trapping...... of nanometer sized silica and polystyrene particles. Based on our analysis, we concluded that gold nano-particles trap more strongly in air than similarly sized polystyrene and silica particles. We found that, in a certain power range, the trapping strength of polystyrene particles is linearly decreasing...
The behavior of potassium in the blast furnace deduced from isotope tracers

International Nuclear Information System (INIS)

Barnes, I; Botha, D.W.S.; Farquharson, D.C.; Gordon, P.T.

1978-01-01

Two tracer tests were done with radioactive potassium (42 K) on blast furnace no. 1, Pretoria Works. Some 80% of the injected 42 K was recovered in 2 1/2 days. About 95% of both radioactive and natural potassium reported in the slag. Mean residence times of 18 and 25 hours confirmed the accumulation of potassium in the furnace. In these tests the slag basicity appeared to be an adequate indicator of furnace conditions governing the behaviour of potassium. A quantitative discontinious model with varying volume CSTR's and interflow controlled according to slag basicity - could be made to fit the results of both tests. The total amounts of K 2 O required by the model - 4 and 9 t respectively - were larger than estimates from input/output imbalance, or from mean residence time of the tracer
An investigation into the potassium body burden in humans with the help of a whole-body counter

International Nuclear Information System (INIS)

Selzer, A.

1981-01-01

The purpose of this study was to examine the available information concerning the potassium body burden of a large number of adults and to find a correlation with other easily measurable body parameters such as mass, height and age so that a normal expected body potassium may be predicted for patients with potassium abnormalities who are also referred to the whole-body counter. The calibration of the whole-body counter to make provision for the differences in geometry and absorption in various body sizes was carried out by injecting a number of people with a small dose of potassium-42 and calculating a correction factor for the potassium standard which is in use daily. All measurements of body potassium were corrected with the calculated correction factor. Fatty tissue in the body contains very little potassium in comparison with muscle tissue and a better correction should therefore be obtained between body potassium and lean body mass. Although it is not possible to predict the smaller potassium abnormalities even when lean body mass is used, the derived regression equation in which lean body mass and age are used, may be viewed as a good first approach in the advance estimation of body potassium
Directed Assembly of Gold Nanoparticles

DEFF Research Database (Denmark)

Westerlund, Axel Rune Fredrik; Bjørnholm, Thomas

2009-01-01

As a complement to common "top-down" lithography techniques, "bottom-up" assembly techniques are emerging as promising tools to build nanoscale structures in a predictable way. Gold nanoparticles that are stable and relatively easy to synthesize are important building blocks in many such structures...... due to their useful optical and electronic properties. Programmed assembly of gold nanoparticles in one, two, and three dimensions is therefore of large interest. This review focuses on the progress from the last three years in the field of directed gold nanoparticle and nanorod assembly using...
Determination of cyanide using a chemiluminescence system composed of permanganate, rhodamine B, and gold nanoparticles

International Nuclear Information System (INIS)

Amjadi, Mohammad; Hassanzadeh, Javad; Manzoori, Jamshid L.

2014-01-01

We describe a new chemiluminescence (CL) system based on the oxidation of rhodamine B (RhoB) with alkaline potassium permanganate in the presence of gold nanoparticles (Au-NPs) and anionic detergent sodium dodecyl sulfate. Free RhoB is weakly chemiluminescent when oxidized with permanganate at alkaline pH values. However, a remarkably strong enhancement of CL is observed in the presence of Au-NPs, probably due to a strong interaction between RhoB and the NPs. The possible mechanism was studied via recording the CL emission. It is also found that the intensity of CL gradually decreases in the presence of cyanide due to its interaction with the Au-NPs. The relation between the decreased CL intensity and cyanide concentration was exploited to develop a method for the determination of cyanide in the 0.01–0.5 μM concentration range, with a detection limit of 2.8 nM. The method was used to determine cyanide in spiked water, urine, and serum. (author)
Microneedle Device Prototype

Science.gov (United States)

2014-05-01

electrochemical characterization of gold electrode (n = 8) array with oxide dielectric defined working electrodes with 1 mM [Fe(CN)6] 3- in 0.1 M potassium ...treatment and an electrochemical treatment were used to clean the arrays. First, gold electrode arrays were sonicated in a solution of 50 mM potassium ... acrylate -based material that is used to manufacture hearing aid shells, was poured into the mold and polymerized with a UV lamp for 20 min. Bores were
Fabrication and characterization of gold nanocrown arrays on a gold film for a high-sensitivity surface plasmon resonance biosensor

Energy Technology Data Exchange (ETDEWEB)

Choi, Munsik; Kim, Nak-hyeon; Eom, Seyoung [Department of Biomedical Engineering, Kyung Hee University, Yongin 446-701 (Korea, Republic of); Kim, Tae Woo [School of East–West Medical Science, Kyung Hee University, Yongin 446-701 (Korea, Republic of); Byun, Kyung Min, E-mail: kmbyun@khu.ac.kr [Department of Biomedical Engineering, Kyung Hee University, Yongin 446-701 (Korea, Republic of); Park, Hyeong-Ho, E-mail: hyeongho.park@kanc.re.kr [Nano Process Division, Korea Advanced Nano Fab Center, Suwon 443-270 (Korea, Republic of)

2015-07-31

We report on a versatile method to fabricate gold nanocrown arrays on a thin gold film based on ultraviolet nanoimprint lithography and tilted evaporation technique. We realize highly ordered 2-dimensional nanocrown arrays and characterize their sizes and morphologies using scanning electron microscopy. To demonstrate an enhanced surface plasmon resonance (SPR) detection by the fabricated gold nanocrown samples, biosensing experiments are performed by measuring SPR angle shift for biotin–streptavidin interaction and bulk refractive index change of dielectric medium. We hope that the suggested plasmonic platform with a high sensitivity could be extended to a variety of biomolecular binding reactions. - Highlights: • Gold nanocrown arrays are produced by nanoimprint lithography and tilted evaporation. • Use of gold nanocrown arrays can improve the sensor sensitivity significantly. • Improved sensitivity is due to enhanced field–matter interaction at gold nanocrowns.
Gold in the hills: patterns of placer gold accumulation under dynamic tectonic and climatic conditions

Science.gov (United States)

Roy, Sam; Upton, Phaedra; Craw, Dave

2018-01-01

Formation of placer accumulations in fluvial environments requires 103-106 or even greater times concentration of heavy minerals. For this to occur, regular sediment supply from erosion of adjacent topography is required, the river should remain within a single course for an extended period of time and the material must be reworked such that a high proportion of the sediment is removed while a high proportion of the heavy minerals remains. We use numerical modeling, constrained by observations of circum-Pacific placer gold deposits, to explore processes occurring in evolving river systems in dynamic tectonic environments. A fluvial erosion/transport model is used to determine the mobility of placer gold under variable uplift rate, storm intensity, and rock mass strength conditions. Gold concentration is calculated from hydraulic and bedload grain size conditions. Model results suggest that optimal gold concentration occurs in river channels that frequently approach a threshold between detachment-limited and transport-limited hydraulic conditions. Such a condition enables the accumulation of gold particles within the framework of a residual gravel lag. An increase in transport capacity, which can be triggered by faster uplift rates, more resistant bedrock, or higher intensity storm events, will strip all bedload from the channel. Conversely, a reduction in transport capacity, triggered by a reduction in uplift rate, bedrock resistance, or storm intensity, will lead to a greater accumulation of a majority of sediments and a net decrease in gold concentration. For our model parameter range, the optimal conditions for placer gold concentration are met by 103 times difference in strength between bedrock and fault, uplift rates between 1 and 5 mm a-1, and moderate storm intensities. Fault damage networks are shown to be a critical factor for high Au concentrations and should be a target for exploration.
Porous Gold Films Fabricated by Wet-Chemistry Processes

Directory of Open Access Journals (Sweden)

Aymeric Pastre

2016-01-01

Full Text Available Porous gold films presented in this paper are formed by combining gold electroless deposition and polystyrene beads templating methods. This original approach allows the formation of conductive films (2 × 106 (Ω·cm−1 with tailored and interconnected porosity. The porous gold film was deposited up to 1.2 μm on the silicon substrate without delamination. An original zirconia gel matrix containing gold nanoparticles deposited on the substrate acts both as an adhesion layer through the creation of covalent bonds and as a seed layer for the metallic gold film growth. Dip-coating parameters and gold electroless deposition kinetics have been optimized in order to create a three-dimensional network of 20 nm wide pores separated by 20 nm thick continuous gold layers. The resulting porous gold films were characterized by GIXRD, SEM, krypton adsorption-desorption, and 4-point probes method. The process is adaptable to different pore sizes and based on wet-chemistry. Consequently, the porous gold films presented in this paper can be used in a wide range of applications such as sensing, catalysis, optics, or electronics.
A new pH-sensitive rectifying potassium channel in mitochondria from the embryonic rat hippocampus.

Science.gov (United States)

Kajma, Anna; Szewczyk, Adam

2012-10-01

Patch-clamp single-channel studies on mitochondria isolated from embryonic rat hippocampus revealed the presence of two different potassium ion channels: a large-conductance (288±4pS) calcium-activated potassium channel and second potassium channel with outwardly rectifying activity under symmetric conditions (150/150mM KCl). At positive voltages, this channel displayed a conductance of 67.84pS and a strong voltage dependence at holding potentials from -80mV to +80mV. The open probability was higher at positive than at negative voltages. Patch-clamp studies at the mitoplast-attached mode showed that the channel was not sensitive to activators and inhibitors of mitochondrial potassium channels but was regulated by pH. Moreover, we demonstrated that the channel activity was not affected by the application of lidocaine, an inhibitor of two-pore domain potassium channels, or by tertiapin, an inhibitor of inwardly rectifying potassium channels. In summary, based on the single-channel recordings, we characterised for the first time mitochondrial pH-sensitive ion channel that is selective for cations, permeable to potassium ions, displays voltage sensitivity and does not correspond to any previously described potassium ion channels in the inner mitochondrial membrane. This article is part of a Special Issue entitled: 17th European Bioenergetics Conference (EBEC 2012). Copyright © 2012 Elsevier B.V. All rights reserved.
Micro-SR-X RF Studies for Archaeological Gold Identification - the Case of Cepharanthin Gold and of Dician Bracelets

International Nuclear Information System (INIS)

Constantinescu, B.; Vasilescu, A.; Radtke, M.; Reinholz, U.

2009-01-01

The goal of the study is to verify if Transylvanian gold was used to manufacture Romanian archaeological objects using information related to trace elements: Sb, Te, Pb - recognized fingerprints for Carpathian Mountains mines and Sn characteristic for the panned river-bed (alluvional) gold. To solve these issues, samples (grains, nuggets,fine gold s and ) from various Transylvanian mines and rivers and some very small (few milligrams) fragments of archaeological objects are measured. During the experiment, point spectra for 22 natural gold samples from Tran sylvania and 18 m icronic s amples from archaeological objects were acquired at 34 keV excitation SR energy, using a spatially resolved SR-XRF set-up mounted for analyses at the hard X-ray beam line - BAMline at BESSY, Berlin. A summary for the characterization of Transylvanian native gold is the following: high (8 - 30%) Ag amounts and low (0.2 - 1%) Cu amounts; placer deposits (Valea Oltului, Stanija, Valea Pianului) contain as fingerprint Sn (150-300 ppm) - most probably from river bed cassiterite; primary deposits present as fingerprints Te (200-2000 ppm), Sb (150-300 ppm) - however, the samples are very inhomogeneous; primary deposit Sacaramb contains Te 0,25%, Sb (500 ppm), but also Sn ( 200 ppm); primary deposit Fizesti presents a big amount of Pb 1%, Sb (350 ppm), traces of Te and also Sn. As concerning the k oson d acian coins, the type w ith monogram i s made from refined (more than 97%) gold with no Sb, Te or Sn traces (remelted gold) and the type w ithout monogram i s clearly made from alluvial gold, partially combined with primary Transylvanian gold (Sn and Sb traces detected). A spectacular application of the micro-SR-XRF studies on native gold was the one of authentication of some recovered heritage artifacts: five Dacian gold bracelets exhibited at the National Museum of Romania's History, Bucharest. The Dacian multi-spiraled bracelets were made of gold; they belong to the classical period of the
Tailoring surface plasmon resonance and dipole cavity plasmon modes of scattering cross section spectra on the single solid-gold/gold-shell nanorod

International Nuclear Information System (INIS)

Chou Chau, Yuan-Fong; Lim, Chee Ming; Kumara, N. T. R. N.; Yoong, Voo Nyuk; Lee, Chuanyo; Huang, Hung Ji; Lin, Chun-Ting; Chiang, Hai-Pang

2016-01-01

Tunable surface plasmon resonance (SPR) and dipole cavity plasmon modes of the scattering cross section (SCS) spectra on the single solid-gold/gold-shell nanorod have been numerically investigated by using the finite element method. Various effects, such as the influence of SCS spectra under x- and y-polarizations on the surface of the single solid-gold/gold-shell nanorod, are discussed in detail. With the single gold-shell nanorod, one can independently tune the relative SCS spectrum width by controlling the rod length and rod diameter, and the surface scattering by varying the shell thickness and polarization direction, as well as the dipole peak energy. These behaviors are consistent with the properties of localized SPRs and offer a way to optically control and produce selected emission wavelengths from the single solid-gold/gold-shell nanorod. The electric field and magnetic distributions provide us a qualitative idea of the geometrical properties of the single solid-gold/gold-shell nanorod on plasmon resonance.
Physiological investigation of gold nanorods toward watermelon.

Science.gov (United States)

Wan, Yujie; Li, Junli; Ren, Hongxuan; Huang, Jin; Yuan, Hong

2014-08-01

The objective of the present study was to evaluate the phytotoxicity and oxidant stress of the gold nanorods toward watermelon, and hence give a quantitative risk assessment of both seeds and plants phase. The seed germination, the activity of antioxidant enzymes, and the contents of soluble protein and malondialdehyde (MDA) have been measured while the plant roots were observed by transmission electron microscopy (TEM). It was found that the gold nanorods significantly promoted the root elongation. Furthermore, the results on the enzymes activities of plant indicated that oxidative stress happened in the plant treated with gold nanorods. However, the gold nanorods resulted in the phytotoxicity toward plant especially at high concentration. The TEM images of the plant roots with and without the treatment of gold nanorods showed the significant different size of starch granules. In conclusion, significant physiological changes of plant occurred after treatment with the gold nanorods.
Reaction of lithium, sodium and potassium polyphosphates with potassium permanganate at elevated temperatures

International Nuclear Information System (INIS)

Paderova, L.V.; Onuchina, T.V.; Kochergin, V.P.

1996-01-01

A study was made on destruction of molten polyphosphates of alkaline metals by potassium permanganate during change of KMnO 4 content, test time and temperature. Ortho-, di, tri- and tetraphosphate-anions, as well as manganese compounds with different oxidation degree were revealed in products of component interaction. Empirical equations of the dependence of the value of average molecular mass on change of melt temperature were derived. 11 refs.; 2 figs.; 2 tabs
Gold leaf counter electrodes for dye-sensitized solar cells

Science.gov (United States)

Shimada, Kazuhiro; Toyoda, Takeshi

2018-03-01

In this study, a gold leaf 100 nm thin film is used as the counter electrode in dye-sensitized solar cells. The traditional method of hammering gold foil to obtain a thin gold leaf, which requires only small amounts of gold, was employed. The gold leaf was then attached to the substrate using an adhesive to produce the gold electrode. The proposed approach for fabricating counter electrodes is demonstrated to be facile and cost-effective, as opposed to existing techniques. Compared with electrodes prepared with gold foil and sputtered gold, the gold leaf counter electrode demonstrates higher catalytic activity with a cobalt-complex electrolyte and higher cell efficiency. The origin of the improved performance was investigated by surface morphology examination (scanning electron microscopy), various electrochemical analyses (cyclic voltammetry, linear sweep voltammetry, and electrochemical impedance spectroscopy), and crystalline analysis (X-ray diffractometry).
Paralytic poliomyelitis associated with Sabin monovalent and bivalent oral polio vaccines in Hungary.

Science.gov (United States)

Estívariz, Concepción F; Molnár, Zsuzsanna; Venczel, Linda; Kapusinszky, Beatrix; Zingeser, James A; Lipskaya, Galina Y; Kew, Olen M; Berencsi, György; Csohán, Agnes

2011-08-01

Historical records of patients with vaccine-associated paralytic poliomyelitis (VAPP) in Hungary during 1961-1981 were reviewed to assess the risk of VAPP after oral polio vaccine (OPV) administration. A confirmed VAPP case was defined as a diagnosis of paralytic poliomyelitis and residual paralysis at 60 days in a patient with an epidemiologic link to the vaccine. Archived poliovirus isolates were retested using polymerase chain reaction and sequencing of the viral protein 1 capsid region. This review confirmed 46 of 47 cases previously reported as VAPP. Three cases originally linked to monovalent OPV (mOPV) 3 and one case linked to mOPV1 presented after administration of bivalent OPV 1 + 3 (bOPV). The adjusted VAPP risk per million doses administered was 0.18 for mOPV1 (2 cases/11.13 million doses), 2.96 for mOPV3 (32 cases/10.81 million doses), and 12.82 for bOPV (5 cases/390,000 doses). Absence of protection from immunization with inactivated poliovirus vaccine or exposure to OPV virus from routine immunization and recent injections could explain the higher relative risk of VAPP in Hungarian children. In polio-endemic areas in which mOPV3 and bOPV are needed to achieve eradication, the higher risk of VAPP would be offset by the high risk of paralysis due to wild poliovirus and higher per-dose efficacy of mOPV3 and bOPV compared with trivalent OPV.
The structural and electronic properties of monovalent sidewall functionalized double-walled carbon nanotubes

International Nuclear Information System (INIS)

Jalili, Seifollah; Jamali, Maryam

2012-01-01

Highlights: ► (6,0)-(13,0) DWCNT, built from (6,0) and (13,0) SWCNTs, is a metallic nanotubes. ► NH 2 /(6,0)-(13,0) and COOH/(6,0)-(13,0) is semimetal and semiconductor, respectively. ► In NH 2 /(6,0)-(13,0) electrons transferred mainly from inner tube to NH 2 group. - Abstract: The structural and electronic properties of (6,0)-(13,0) double-walled carbon nanotubes (DWCNTs) and monovalent sidewall functionalized DWCNTs with –NH 2 and –COOH groups were studied using density functional theory. The results show that pure (6,0)-(13,0) DWCNTs are metallic. However, by functionalizing a DWCNT, local distortions are induced in the outer tube sidewall along the radial direction. The resulting structures, NH 2 /(6,0)-(13,0) and COOH/(6,0)-(13,0) DWCNTs, exhibit significant structural changes, and are semimetal with no energy gap and semiconducting with a small energy gap, respectively. In NH 2 /(6,0)-(13,0) DWCNTs, new electronic states are created and distributed on the outer wall and NH 2 group by electron transfer from the inner tube to the NH 2 group. In COOH/(6,0)-(13,0) DWCNTs, new states are created and distributed on the inner wall, but there is insignificant charge transfer between the inner tube and the COOH group. These results confirm that local atomic structural distortion on DWCNTs caused by sidewall functionalization can modify the electronic structures of DWCNTs.
Impact and Effectiveness of Monovalent Rotavirus Vaccine Against Severe Rotavirus Diarrhea in Ghana.

Science.gov (United States)

Armah, George; Pringle, Kimberly; Enweronu-Laryea, Christabel C; Ansong, Daniel; Mwenda, Jason M; Diamenu, Stanley K; Narh, Clement; Lartey, Belinda; Binka, Fred; Grytdal, Scott; Patel, Manish; Parashar, Umesh; Lopman, Ben

2016-05-01

Ghana was among the first African nations to introduce monovalent rotavirus vaccine (RV1) into its childhood immunization schedule in April 2012. We aimed to assess the impact of vaccine introduction on rotavirus and acute gastroenteritis (AGE) hospitalizations and to estimate vaccine effectiveness (VE). Using data from 2 teaching hospitals, monthly AGE and rotavirus admissions by age were examined 40 months before and 31 months after RV1 introduction using interrupted time-series analyses. From January 2013, we enrolled children vaccination by rotavirus case-patient status, controlling for potential confounders. Vaccine coverage ranged from 95% to 100% for dose 1 and 93% to 100% for dose 2. In the first 3 years after vaccine introduction, the percentage of hospital admissions positive for rotavirus fell from 48% in the prevaccine period to 28% (49% adjusted rate reduction; 95% confidence interval [CI], 32%-63%) postvaccination among vaccine coverage, it was not possible to arrive at robust VE estimates; any-dose VE against rotavirus hospitalization was estimated at 60% (95% CI, -2% to 84%;P= .056). Results from the first 3 years following RV1 introduction suggest substantial reductions of pediatric diarrheal disease as a result of vaccination. Our VE estimate is consistent with the observed rotavirus decrease and with efficacy estimates from elsewhere in sub-Saharan Africa. Published by Oxford University Press for the Infectious Diseases Society of America 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

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