Successive potassium hydroxide testing for improved diagnosis of tinea pedis.

Science.gov (United States)

Karaman, Bilge F; Topal, Suhan G; Aksungur, Varol L; Ünal, İlker; İlkit, Macit

2017-08-01

In this study, we investigated the role of successive potassium hydroxide (KOH) tests for the diagnosis of tinea pedis with different clinical presentations. The study included 135 patients with 200 lesions that were clinically suspicious for tinea pedis. Three samples of skin scrapings were taken from each lesion in the same session and were examined using a KOH test. This study offers an inexpensive, rapid, and useful technique for the daily practice of clinicians and mycologists managing patients with clinically suspected tinea pedis.

Comparison of ethanolamine and potassium hydroxide as quantitative trapping agents for radiolabeled CO2 in metabolism studies

International Nuclear Information System (INIS)

Medinsky, M.A.

1984-01-01

The efficiency of ethanolamine and potassium hydroxide as trapping agents for CO 2 was tested using a flow of 500 ml/min through CO 2 absorption towers containing trapping solutions. Radiolabeled CO 2 was produced by acidification of suspensions containing Ba 14 CO 3 . With 200 ml of ethanolamine, trapping efficiency of 14 CO 2 decreased when only 5% or less of the amount of ethanolamine available had reacted (22 mmoles of CO 2 trapped). In contrast, use of 200 ml of 1 M or 5 M KOH was effective in retaining 88 mmoles of CO 2 . This is equivalent to the amount of CO 2 produced by a rat over an 8-hour period

Reactions between rocks and the hydroxides of calcium, sodium and potassium: progress report no. 1

International Nuclear Information System (INIS)

Van Aardt, J.H.P.; Visser, S.

1982-01-01

The reaction between the hydroxides of calcium, sodium and potassium, and clay minerals, feldspars, and some rocks (aggregates for use in concrete) was investigated. The reaction products were examined by means of x-ray diffraction and chemical analysis. The solid reaction products identified were hydrated calcium silicates,hydrated calcium aluminates, and hydrated calcium alumina silicates. It was found that, in the presence of water, calcium hydroxide liberated alkali into solution if the rocks and minerals contained alkali metals in their structure. Two crystalline hydrated sodium calcium silicates (12A and 16A) were prepared in the system Na 2 O-CaO-SiO 2 -H 2 O at 80 degrees Celsius. The one compound (12A) was also observed when sodium hydroxide plus calcium hydroxide and water reacted with silica- or silicate-containing rocks

Role of lauric acid-potassium hydroxide concentration on bacterial contamination of spray washed broiler carcasses

Science.gov (United States)

A series of experiments were conducted to examine reductions in bacterial contamination of broiler carcasses washed in a spray cabinet with various concentrations of lauric acid (LA)-potassium hydroxide (KOH) solutions. Fifty eviscerated carcasses and 5 ceca were obtained from the processing line of...

Nickel silicide thin films as masking and structural layers for silicon bulk micro-machining by potassium hydroxide wet etching

International Nuclear Information System (INIS)

Bhaskaran, M; Sriram, S; Sim, L W

2008-01-01

This paper studies the feasibility of using titanium and nickel silicide thin films as mask materials for silicon bulk micro-machining. Thin films of nickel silicide were found to be more resistant to wet etching in potassium hydroxide. The use of nickel silicide as a structural material, by fabricating micro-beams of varying dimensions, is demonstrated. The micro-structures were realized using these thin films with wet etching using potassium hydroxide solution on (1 0 0) and (1 1 0) silicon substrates. These results show that nickel silicide is a suitable alternative to silicon nitride for silicon bulk micro-machining

Influence of washing time on residual contamination of carcasses sprayed with lauric acid-potassium hydroxide.

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A series of experiments were conducted to examine reductions in bacterial contamination of broiler carcasses washed for various times in a spray cabinet with a 2% lauric acid (LA)-1% potassium hydroxide (KOH) (w/v) solution. Forty eviscerated carcasses and 5 ceca were obtained from the processing l...

[Determination of total mass and morphology analysis of heavy metal in soil with potassium biphthalate-sodium hydroxide by ICP-AES].

Science.gov (United States)

Qu, Jiao; Yuan, Xing; Cong, Qiao; Wang, Shuang

2008-11-01

Blank soil was used as quality controlling samples, soil sample dealt by potassium biphthalate-sodium hydroxide buffer solution was used as check sample, mixed acid HNO3-HF-HClO4 was chosen to nitrify soil samples, and plasma emission spectrometer (ICP-AES) was used as detecting method. The authors determined the total metal mass of Mo, Pb, As, Hg, Cr, Cd, Zn, Cu and Ni in the extracted and dealt soil samples, and determined the mass of Mo, Pb, As, Hg, Cr, Cd, Zn, Cu and Ni in the three chemical morphologies, including acid extractable morphology, oxide associated morphology, and organics associated modality. The experimental results indicated that the different pH of potassium biphthalate-sodium hydroxide buffer solution had obvious influence on the total mass of heavy metal and morphology transformation. Except for metal element Pb and Zn, the addition of different pH potassium dihydrogen phosphate-sodium hydroxide buffer solution could accelerate the soil samples nitrification and the total mass determination of heavy metal in the soil samples. The potassium biphthalate-sodium hydroxide buffer solution could facilitate the acid extractable morphology of Cr, Cu, Hg and Pb, oxidation associated morphology of As, Hg, Pb and Zn and the organic associated morphology transforming of As and Hg. At pH 5.8, the maximum acid extractable morphology contents of Cu and Hg were 2.180 and 0.632 mg x kg(-1), respectively; at pH 6.2, the maximal oxidation associated morphology content of Pb could achieve 27.792 mg x kg(-1); at pH 6.0, the maximum organic associated morphology content of heavy metal Hg was 4.715 mg x kg(-1).

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...

Effects of potassium hydroxide post-treatments on the field-emission properties of thermal chemical vapor deposited carbon nanotubes.

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Lee, Li-Ying; Lee, Shih-Fong; Chang, Yung-Ping; Hsiao, Wei-Shao

2011-12-01

In this study, a simple potassium hydroxide treatment was applied to functionalize the surface and to modify the structure of multi-walled carbon nanotubes grown on silicon substrates by thermal chemical vapor deposition. Scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, and energy dispersive spectrometry were employed to investigate the mechanism causing the modified field-emission properties of carbon nanotubes. From our experimental data, the emitted currents of carbon nanotubes after potassium hydroxide treatment are enhanced by more than one order of magnitude compared with those of untreated carbon nanotubes. The emitted current density of carbon nanotubes increases from 0.44 mA/cm2 to 7.92 mA/cm2 after 30 minutes KOH treatment. This technique provides a simple, economical, and effective way to enhance the field-emission properties of carbon nanotubes.

In vitro antibacterial effect of calcium hydroxide combined with chlorhexidine or iodine potassium iodide on Enterococcus faecalis.

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Sirén, Eva K; Haapasalo, Markus P P; Waltimo, Tuomas M T; Ørstavik, Dag

2004-08-01

Several studies have shown a higher success rate of root canal therapy when the canal is free from bacteria at the time of obturation. Treatment strategies that are designed to eliminate this microflora should include agents that can effectively disinfect the root canal. Enterococcus faecalis is often associated with persistent endodontic infections. While in vivo studies have indicated calcium hydroxide to be the most effective all-purpose intracanal medicament, iodine potassium iodide (IKI) and chlorhexidine (CHX) may be able to kill calcium hydroxide-resistant bacteria. Supplementing the antibacterial activity of calcium hydroxide with IPI or CHX preparations was studied in bovine dentine blocks. While calcium hydroxide was unable to kill E. faecalis in the dentine, calcium hydroxide combined with IKI or CHX effectively disinfected the dentine. The addition of CHX or IKI did not affect the alkalinity of the calcium hydroxide suspensions. It may be assumed that combinations also have the potential to be used as long-term medication. Cytotoxicity tests using the neutral red method indicated that the combinations were no more toxic than their pure components.

Surface engineering of titanium with potassium hydroxide and its effects on the growth behavior of mesenchymal stem cells.

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Cai, Kaiyong; Lai, Min; Yang, Weihu; Hu, Ran; Xin, Renlong; Liu, Qing; Sung, K L Paul

2010-06-01

To improve the corrosion resistance and biological performance of commercially pure titanium (cp-Ti) substrates, potassium hydroxide was employed to modify the surfaces of titanium substrates, followed by biomimetic deposition of apatite on the substrates in a simulated body fluid. The morphologies of native and treated titanium substrates were characterized by field emission scanning electron microscopy (FE-SEM). Treatment with potassium hydroxide led to the formation of intermediate layers of potassium titanate on the surfaces of titanium substrates, while apatite was subsequently deposited onto the intermediate layer. The formation of potassium titanate and apatite was confirmed by thin-film X-ray diffraction and FE-SEM equipped with energy dispersive spectroscopy, respectively. Electrochemical impedance spectroscopy showed that the formed potassium titanate layer improved the corrosion-resistance properties of titanium substrates. The influence of modified titanium substrates on the biological behavior of mesenchymal stem cells (MSCs), including osteogenic differentiation, was investigated in vitro. Compared with cp-Ti substrates, MSCs cultured onto alkali- and heat-treated titanium substrates and apatite-deposited titanium substrates displayed significantly higher (P<0.05 or P<0.01) proliferation and differentiation levels of alkaline phosphatase and osteocalcin in 7 and 14day cultures, respectively. More importantly, our results suggest that the modified titanium substrates have great potential for inducing MSCs to differentiate into osteoblasts. The approach presented here may be exploited to fabricate titanium-based implants. Copyright 2009 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

The effects of potassium and rubidium hydroxide on the alkali-silica reaction

International Nuclear Information System (INIS)

Shomglin, K.; Turanli, L.; Wenk, H.-R.; Monteiro, P.J.M.; Sposito, G.

2003-01-01

Expansion of mortar specimens prepared with an aggregate of mylonite from the Santa Rosa mylonite zone in southern California was studied to investigate the effect of different alkali ions on the alkali-silica reaction in concrete. The expansion tests indicate that mortar has a greater expansion when subjected to a sodium hydroxide bath than in a sodium-potassium-rubidium hydroxide bath. Electron probe microanalysis (EPMA) of mortar bars at early ages show that rubidium ions, used as tracer, were present throughout the sample by the third day of exposure. The analysis also shows a high concentration of rubidium in silica gel from mortar bars exposed to bath solutions containing rubidium. The results suggest that expansion of mortar bars using ASTM C 1260 does not depend on the diffusion of alkali ions. The results indicate that the expansion of alkali-silica gel depends on the type of alkali ions present. Alkali-silica gel containing rubidium shows a lower concentration of calcium, suggesting competition for the same sites

Comparison of ethanolamine and potassium hydroxide as quantitative trapping agents for radiolabeled CO2 in metabolism studies

International Nuclear Information System (INIS)

Medinsky, M.A.

1986-01-01

The efficiency of ethanolamine and potassium hydroxide (KOH) as trapping agents for CO 2 was determined using a flow of 500 mL/min through CO 2 absorption towers containing trapping solution. Radiolabeled 14 CO 2 was produced by acidification of suspensions containing Ba 14 CO 3 . Both 100% ethanolamine and 5M ethanolamine in 2-methoxyethanol were evaluated. With 200 mL of either solution, trapping efficiency of 14 CO 2 decreased when only 5% or less of the amount of ethanolamine available had reacted (22 mmoles of CO 2 ) trapped). In contrast, use of 200 mL of 1M or 5M KOH was effective in retaining 88 mmoles of CO 2 . This is equivalent to the amount of CO 2 produced by a rat over an 8-hr period. In summary, with flow rates commonly used in in vivo metabolism studies, the trapping efficiency of ethanolamine was far less than the theoretical efficiency. In these types of studies KOH would be a more suitable trapping agent or, if used, ethanolamine solutions must be changed frequently

In-situ injection of potassium hydroxide into briquetted wheat straw and meadow grass - Effect on biomethane production.

Science.gov (United States)

Feng, Lu; Moset, Veronica; Li, Wanwu; Chen, Chang; Møller, Henrik Bjarne

2017-09-01

Alkaline pretreatment of lignocellulosic biomass has been intensively investigated but heavy water usage and environmental pollution from wastewater limits its industrial application. This study presents a pretreatment technique by in-situ injection of potassium hydroxide concentrations ranging from 0.8% to 10% (w/w) into the briquetting process of wheat straw and meadow grass. Results show that the biomethane yield and hydrolysis rate was improved significantly with a higher impact on wheat straw compared to meadow grass. The highest biomethane yield from wheat straw briquettes of 353mL.g -1 VS was obtained with 6.27% (w/w) potassium hydroxide injection, which was 14% higher than from untreated wheat straw. The hydrolysis rates of wheat straw and meadow grass increased from 4.27×10 -2 to 5.32×10 -2 d -1 and 4.19×10 -2 to 6.00×10 -2 d -1 , respectively. The low water usage and no wastewater production make this a promising technology. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bacteria recovered from whole-carcass rinsates of broiler carcasses washed in a spray cabinet with lauric acid-potassium hydroxide

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The effect of spray washing carcasses with lauric acid (LA)-potassium hydroxide (KOH) on bacteria recovered from whole-carcass-rinsates (WCR) was examined. Skin of carcasses was inoculated with a cecal paste containing antibiotic resistant strains of Escherichia coli, Salmonella Typhimirum, and Camp...

The concentration of the coolant 7Li in Kozloduy Nuclear Power Plant operating with potassium hydroxide as an alkalizing reagent (possible impact on the occurrence of axial offset anomaly)

International Nuclear Information System (INIS)

Dobrevski, I.D.; Minkova, K.F.; Ivanova, R.A.

2003-01-01

The phenomenon of axial offset anomaly (AOA) has occurred in a number of PWRs operating with extended fuel cycles and high boiling duty cores. Up to now AOA has been observed in PWRs operating with lithium hydroxide and the alkalizing reagent used for pH adjustment in boric acid water solutions. Since AOA is connected with the LiBO 2 precipitation in porous corrosion product deposits on the fuel cladding surfaces, we could presume that the replacement of lithium hydroxide with potassium hydroxide will avoid AOA. Nowadays there is a lack of observed AOA in VVER, i.e., a lack of formation of lithium metaborate (LiBO 2 ) deposits on the fuel element surfaces by coolant alkalization with potassium hydroxide. Nevertheless, the concentrations of 7 Li appear in the coolant, as a product of the neutron reaction with boron: 10 B (n,α) → 7 Li (n, α). As a consequence the possibility it is not excluded of LiBO 2 formation in VVERs with potassium hydroxide water chemistry. The aim of this study is to inform the reader about the development of the concentration of the coolant lithium concentration during the fuel cycles of VVERs and to discuss the possibility of LiBO 2 formation under VVER operation conditions. (orig.)

Determination of total ribonucleotide pool in plant materials by high-pH anion-exchange high-performance liquid chromatography following extraction with potassium hydroxide.

Science.gov (United States)

Riondet, Christophe; Morel, Sylvain; Alcaraz, Gérard

2005-06-10

A new, improved method that only requires a potassium hydroxide extraction procedure is presented for the analysis of a full nucleotide pool in plant materials. Quantification was performed by high-pH anion-exchange chromatography (HPAEC) with UV detection after a potassium hydroxide extraction, and allowed the quantification of 13 linear ribonucleotides in a single run. The method has been validated by comparison of six extraction methods and also by measurement of the intracellular nucleotide levels of three plant species (cell cultures and leaves). The evolution of the nucleotide pool of Nicotiana tabacum cell culture during growth has also been measured, and showed an increase in the pool until the fifth day, where the growth rate reaches a maximum, after which a decrease was observed.

Evaluation of a new fluorescent reagent, fluorescent brightener 85, for the diagnosis of suspected onychomycosis compared with potassium hydroxide.

Science.gov (United States)

Yue, Xueping; Wang, Aiping; Wang, Hongwei; Li, Qing; Yue, Xiuling

2018-04-01

Onychomycosis is a common fungal infection in dermatology clinics. The commonly used diagnostic method, potassium hydroxide (KOH) direct microscopy, does not have a high-positive detection rate. Therefore, a new diagnostic method is needed to confirm onychomycosis. The objective of this research was to use fluorescent brightener 85 (FB 85), a new fluorescent reagent for fungi detection, and to evaluate this new method based on the diagnostic positive rate, accuracy and efficiency in suspected onychomycosis compared with the KOH method. Subungual debris was collected from clinically suspected onychomycosis cases and divided into two parts. The parts were examined by FB 85 and 10% KOH solution, respectively. In total, 108 patients with suspected onychomycosis were recruited. The positive rates of FB 85 and KOH were 88.9% and 55.6%, respectively. The patients showed significant statistical differences (P < .001). Compared with the KOH method, the FB 85 fluorescent method was an accurate and efficient method with a higher positive rate. This method could increase the diagnostic accuracy and efficiency of onychomycosis detection. © 2017 Blackwell Verlag GmbH.

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.

Potassium hydroxide pulping of rice straw in biorefinery initiatives.

Science.gov (United States)

Jahan, M Sarwar; Haris, Fahmida; Rahman, M Mostafizur; Samaddar, Purabi Rani; Sutradhar, Shrikanta

2016-11-01

Rice straw is supposed to be one of the most important lignocellulosic raw materials for pulp mill in Asian countries. The major problem in rice straw pulping is silica. The present research is focused on the separation of silica from the black liquor of rice straw pulping by potassium hydroxide (KOH) and pulp evaluation. Optimum KOH pulping conditions of rice straw were alkali charge 12% as NaOH, cooking temperature 150°C for 2h and material to liquor ratio, 1:6. At this condition pulp yield was 42.4% with kappa number 10.3. KOH pulp bleached to 85% brightness by D0EpD1 bleaching sequences with ClO2 consumption of 25kg/ton of pulp. Silica and lignin were separated from the black liquor of KOH pulping. The amount of recovered silica, lignin and hemicelluloses were 10.4%, 8.4% and 13.0%. The papermaking properties of KOH pulp from rice straw were slightly better than those of corresponding NaOH pulp. Copyright © 2016 Elsevier Ltd. All rights reserved.

Potassium Hydroxide Impregnated Alumina (KOH-Alumina) as a Recyclable Catalyst for the Solvent-Free Multicomponent Synthesis of Highly Functionalized Substituted Pyridazines and/or Substituted Pyridazin-3(2H)-ones under Microwave Irradiation.

Science.gov (United States)

Mecadon, Hormi; Myrboh, Bekington

2011-01-01

The work described herein employs potassium hydroxide impregnated alumina (KOH-alumina) as a mild, efficient, and recyclable catalyst for a one-pot solvent-free and environmentally safer synthesis of 3,4,6-triarylpyridazines and some substituted pyridazines from active methylene carbonyl species, 1,2-dicarbonyls, and hydrazine hydrate by microwave (MW) irradiation. The method offers highly convergent, inexpensive, and functionality-tolerable procedure for rapid access to important pyridazine compounds in good yields.

Homogeneous catalysis of deuterium transfer by potassium hydroxide and potassium methoxide D2-H2O and D2-CH3OH exchange

International Nuclear Information System (INIS)

Strathdee, G.G.; Garner, D.M.; Given, R.M.

1977-01-01

The kinetics and mechanism of exchange of deuterium between D 2 and water and between D 2 and methanol, catalyzed respectively by concentrated potassium hydroxide and potassium methoxide, has been studied between 348 and 398 K. In the D 2 -KOH-H 2 O case, the transfer of deuterium was found to be controlled by the rate of activation of the D 2 molecule by OH - . Rapid exchange of D + with the aqueous solution followed. From the D 2 -KOCH 3 -CH 3 OH studies, it was concluded that deuterium exchange depended upon the rates of both D 2 activation by methoxide and interaction of the solvent with the transition, or encounter, complex. The dependence of second-order rate constants on solvent activity for both systems was determined by normalization of the exchange reaction rates to unit reagent activity. Analysis of the kinetic isotope effects for each system suggested that their increase with base concentration or temperature was due to solvation effects. (author)

Adsorption of pharmaceuticals to microporous activated carbon treated with potassium hydroxide, carbon dioxide, and steam.

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Fu, Heyun; Yang, Liuyan; Wan, Yuqiu; Xu, Zhaoyi; Zhu, Dongqiang

2011-01-01

Adsorption of sulfapyridine, tetracycline, and tylosin to a commercial microporous activated carbon (AC) and its potassium hydroxide (KOH)-, CO-, and steam-treated counterparts (prepared by heating at 850°C) was studied to explore efficient adsorbents for the removal of selected pharmaceuticals from water. Phenol and nitrobenzene were included as additional adsorbates, and nonporous graphite was included as a model adsorbent. The activation treatments markedly increased the specific surface area and enlarged the pore sizes of the mesopores of AC (with the strongest effects shown on the KOH-treated AC). Adsorption of large-size tetracycline and tylosin was greatly enhanced, especially for the KOH-treated AC (more than one order of magnitude), probably due to the alleviated size-exclusion effect. However, the treatments had little effect on adsorption of low-size phenol and nitrobenzene due to the predominance of micropore-filling effect in adsorption and the nearly unaffected content of small micropores causative to such effect. These hypothesized mechanisms on pore-size dependent adsorption were further tested by comparing surface area-normalized adsorption data and adsorbent pore size distributions with and without the presence of adsorbed antibiotics. The findings indicate that efficient adsorption of bulky pharmaceuticals to AC can be achieved by enlarging the adsorbent pore size through suitable activation treatments. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

How to teach the potassium hydroxide preparation: a disappearing clinical art form.

Science.gov (United States)

Wilkison, Bart D; Sperling, Leonard C; Spillane, Anne P; Meyerle, Jon H

2015-08-01

Using potassium hydroxide (KOH) preparations in the diagnosis of superficial fungal infections is a technique that has been handed down from teacher to apprentice for more than 100 years. The technique is simple, accurate, and inexpensive; however, there is reason to believe it is falling to the wayside in favor of empiric treatment, especially in primary care settings. To continue the use of this valuable diagnostic aid, a system of teaching the KOH preparation to the next generation of physicians (ie, medical students, residents) is proposed with emphasis on facilitating the process by storing viable skin samples infected with dermatophytes for long periods of time. This technique obviates the need to find suitably infected patients before each teaching laboratory. This technique also is appropriate to refresh the skills of practicing physicians as they prepare for point-of-care testing assessments.

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...

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...

Use of potassium hydroxide, Giemsa and calcofluor white staining techniques in the microscopic evaluation of corneal scrapings for diagnosis of fungal keratitis.

Science.gov (United States)

Zhang, Weihong; Yang, Huashan; Jiang, Lili; Han, Lei; Wang, Liya

2010-01-01

The aim of this study was to develop a quick and economical method for the diagnosis of fungal keratitis. Corneal scrapings were obtained from consecutive patients (n = 165) with clinically suspected fungal keratitis and were used for culture and to prepare two smears. Potassium hydroxide stain followed by calcofluor white stain was added to one smear and Giemsa stain followed by calcofluor white stain was added to the second. In comparison with the fungal culture results, the sensitivity of potassium hydroxide wet mounts was 81.0% and following the addition of calcofluor white was 96.6% in diagnosing fungal keratitis, whereas sensitivity using Giemsa stain was 39.7% and following the addition of calcofluor white was 98.3%. The Giemsa stain detected 23 cases of bacterial infection, of which six cases were mixed fungal and bacterial infections. Giemsa stain followed by calcofluor white was considered to be the better method for diagnosing fungal keratitis due to its high sensitivity combined with its ability to identify bacterial or mixed infections.

Study of Activated Carbons by Pyrolysis of Mangifera Indica Seed (Mango in Presence of Sodium and Potassium Hydroxide

Directory of Open Access Journals (Sweden)

J. C. Moreno-Piraján

2012-01-01

Full Text Available Activated carbons (ACs were prepared by pyrolysis of seeds mango in presence of sodium and potassium hydroxide (chemical activities. Seeds mango from Colombian Mango cultives were impregnated with aqueous solutions of NaOH and KOH following a variant of the incipient wetness method. Different concentrations were used to produce impregnation ratios of 3:1 (weight terms. Activation was carried out under argon flow by heating to 823 K with 1 h soaking time. The porous texture of the obtained ACs was characterized by physical adsorptions of N2 at 77 K and CO2 at 273 K. The impregnation ration and hydroxide type had a strong influence on the pore structure of these ACs, which could be easily controlled by simply varying the proportion of the hydroxides used in the activation. Thus, the development of porosity for precursors with low structural order (high reactivity is better with NaOH than KOH, whereas the opposite is observed for the highly ordered ones. Variable adsorption capacities and porosity distributions can be achieved depending on the activating agent selected. In general, KOH produces activated carbons with narrower micropore distributions than those prepared by NaOH.

KINETICS OF PALM OIL TRANSESTERIFICATION IN METHANOL WITH POTASSIUM HYDROXIDE AS A CATALYST

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Yoeswono Yoeswono

2010-06-01

Full Text Available A study on palm oil transesterification to evaluate the effect of some parameters in the reaction on the reaction kinetics has been carried out. Transesterification was started by preparing potassium methoxide from potassium hydroxide and methanol and then mixed it with the palm oil. An aliquot was taken at certain time interval during transesterification and poured into test tube filled with distilled water to stop the reaction immediately. The oil phase that separated from the glycerol phase by centrifugation was analyzed by 1H-NMR spectrometer to determine the percentage of methyl ester conversion. Temperature and catalyst concentration were varied in order to determine the reaction rate constants, activation energies, pre-exponential factors, and effective collisions. The results showed that palm oil transesterification in methanol with 0.5 and 1 % w/w KOH/palm oil catalyst concentration appeared to follow pseudo-first order reaction. The rate constants increase with temperature. After 13 min of reaction, More methyl esters were formed using KOH 1 % than using 0.5 % w/w KOH/palm oil catalyst concentration. The activation energy (Ea and pre-exponential factor (A for reaction using 1 % w/w KOH was lower than those using 0.5 % w/w KOH.   Keywords: palm oil, transesterification, catalyst, first order kinetics, activation energy, pre-exponential factor

A prospective, open, comparative study of 5% potassium hydroxide solution versus cryotherapy in the treatment of genital warts in men *

OpenAIRE

Camargo, Caio Lamunier de Abreu; Belda, Walter; Fagundes, Luiz Jorge; Romiti, Ricardo

2014-01-01

BACKGROUND: Genital warts are caused by human papillomavirus infection and represent one of the most common sexually transmitted diseases. Many infections are transient but the virus may recur, persist, or become latent. To date, there is no effective antiviral treatment to eliminate HPV infection and most therapies are aimed at the destruction of visible lesions. Potassium hydroxide is a strong alkali that has been shown to be safe and effective for the treatment of genital warts and mollusc...

An Alternative and Rapid Method for the Extraction of Nucleic Acids from Ixodid Ticks by Potassium Acetate Procedure

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Islay Rodríguez

2014-08-01

Full Text Available Four variants of the potassium acetate procedure for DNA extraction from ixodid ticks at different stage of their life cycles were evaluated and compared with phenol-chloroform and ammonium hydroxide methods. The most rapid and most efficient variant was validated in the DNA extraction procedure from the engorged ticks collected from bovine, canine as well as from house ticks for the screening of Borrelia burgdorferi sensu lato, Anaplasma spp. and Babesia spp. The ammonium hydroxide procedure was used for non-engorged ticks. All the variants were efficient and allowed obtaining PCR-quality material according to the specific amplification of 16S rRNA gene fragment of the original tick. DNA extracted from the ticks under the study was tested by multiplex PCR for the screening of tick-borne pathogens. Anaplasma spp. and Babesia spp. amplification products were obtained from 29/48 extracts. Ammonium hydroxide protocol was not efficient for two extracts. Detection of amplification products from the PCR indicated that DNA had been successfully extracted. The potassium acetate procedure could be an alternative, rapid, and reliable method for DNA extraction from the ixodid ticks, mainly for poorly-resourced laboratories.

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.

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.

Mixing Acid Salts and Layered Double Hydroxides in Nanoscale under Solid Condition

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Nakayama, Hirokazu; Hayashi, Aki

2014-01-01

The immobilization of potassium sorbate, potassium aspartate and sorbic acid in layered double hydroxide under solid condition was examined. By simply mixing two solids, immobilization of sorbate and aspartate in the interlayer space of nitrate-type layered double hydroxide, so called intercalation reaction, was achieved, and the uptakes, that is, the amount of immobilized salts and the interlayer distances of intercalation compounds were almost the same as those obtained in aqueous solution...

Treatment of pediatric molluscum contagiosum with 10% potassium hydroxide solution.

Science.gov (United States)

Can, Burce; Topaloğlu, Filiz; Kavala, Mukaddes; Turkoglu, Zafer; Zindancı, Ilkin; Sudogan, Sibel

2014-06-01

Molluscum contagiosum (MC) is a common cutaneous viral infection of the skin that is frequently seen in children. Although lesions can resolve spontaneously, treatment is mandatory because of the psychological effect of widespread lesions in children. Potassium hydroxide (KOH) is a strong alkali that has been used by dermatologists for a long time in identifying the fungal infections from skin scrapings. We evaluated 40 children with MC for the safety and efficacy of treatment with topical 10% KOH aqueous solution. Parents were instructed to apply a 10% KOH aqueous solution, twice daily, with a cotton stick to all lesions. Treatment was continued till the lesions showed signs of inflammation or superficial ulceration. Assessments of response and side effects were performed at the end of week 2, week 4, week 8 and week 12. We found complete clearance of lesions in 37 (92.5%) patients receiving topical 10%KOH solution after a mean period of four weeks. Three children dropped out of the study; two children reported severe stinging of the lesions and discontinued the treatment; the other patient developed hypopigmentation during the treatment. Local side effects were observed in 12 children (32.4%). Even though 10% KOH solution is associated with some local side effects, it is a safe, effective, inexpensive and noninvasive alternative treatment of MC in children.

Structural and nano-mechanical properties of Calcium Silicate Hydrate (C-S-H) formed from alite hydration in the presence of sodium and potassium hydroxide

International Nuclear Information System (INIS)

Mendoza, Oscar; Giraldo, Carolina; Camargo, Sergio S.; Tobón, Jorge I.

2015-01-01

This research evaluates the effect of sodium and potassium hydroxide on the structure and nano-mechanical properties of Calcium Silicate Hydrate (C-S-H) formed from the hydration of pure alite. Monoclinic (MIII) alite was synthesized and hydrated, using water-to-alite ratios of 0.5 and 0.6 and additions of 10% NaOH and KOH by weight of alite. Based on results of X-ray diffraction, isothermal calorimetry, thermogravimetric analysis, Nuclear Magnetic Resonance and nanoindentation, two different effects of the alkaline hydroxides on the hydration reaction of alite, both at early and later ages, can be identified: (i) a differentiated hydration process, attributed to an enhancement in calcium hydroxide (CH) precipitation and a stimulation of the C-S-H nuclei; and (ii) an increase in the elastic modulus of the C-S-H aggregations, attributed to an electrostatic attraction between positive charges from the alkaline cations and negative charges from the C-S-H structure

Structural and nano-mechanical properties of Calcium Silicate Hydrate (C-S-H) formed from alite hydration in the presence of sodium and potassium hydroxide

Energy Technology Data Exchange (ETDEWEB)

Mendoza, Oscar, E-mail: oamendoz@unal.edu.co [Grupo del Cemento y Materiales de Construcción (CEMATCO). Universidad Nacional de Colombia, Facultad de Minas, Medellín (Colombia); Giraldo, Carolina [Cementos Argos S.A., Medellín (Colombia); Camargo, Sergio S. [Engenharia Metalúrgica e de Materiais, Universidade Federal do Rio de Janeiro/COPPE, Rio de Janeiro (Brazil); Tobón, Jorge I. [Grupo del Cemento y Materiales de Construcción (CEMATCO). Universidad Nacional de Colombia, Facultad de Minas, Medellín (Colombia)

2015-08-15

This research evaluates the effect of sodium and potassium hydroxide on the structure and nano-mechanical properties of Calcium Silicate Hydrate (C-S-H) formed from the hydration of pure alite. Monoclinic (MIII) alite was synthesized and hydrated, using water-to-alite ratios of 0.5 and 0.6 and additions of 10% NaOH and KOH by weight of alite. Based on results of X-ray diffraction, isothermal calorimetry, thermogravimetric analysis, Nuclear Magnetic Resonance and nanoindentation, two different effects of the alkaline hydroxides on the hydration reaction of alite, both at early and later ages, can be identified: (i) a differentiated hydration process, attributed to an enhancement in calcium hydroxide (CH) precipitation and a stimulation of the C-S-H nuclei; and (ii) an increase in the elastic modulus of the C-S-H aggregations, attributed to an electrostatic attraction between positive charges from the alkaline cations and negative charges from the C-S-H structure.

Potential of potassium hydroxide pretreatment of switchgrass for fermentable sugar production.

Science.gov (United States)

Sharma, Rajat; Palled, Vijaykumar; Sharma-Shivappa, Ratna R; Osborne, Jason

2013-02-01

Chemical pretreatment of lignocellulosic biomass has been extensively investigated for sugar generation and subsequent fuel production. Alkaline pretreatment has emerged as one of the popular chemical pretreatment methods, but most attempts thus far have utilized NaOH for the pretreatment process. This study aimed at investigating the potential of potassium hydroxide (KOH) as a viable alternative alkaline reagent for lignocellulosic pretreatment based on its different reactivity patterns compared to NaOH. Performer switchgrass was pretreated at KOH concentrations of 0.5-2% for varying treatment times of 6-48 h, 6-24 h, and 0.25-1 h at 21, 50, and 121 °C, respectively. The pretreatments resulted in the highest percent sugar retention of 99.26% at 0.5%, 21 °C, 12 h while delignification up to 55.4% was observed with 2% KOH, 121 °C, 1 h. Six pretreatment conditions were selected for subsequent enzymatic hydrolysis with Cellic CTec2® for sugar generation. The pretreatment condition of 0.5% KOH, 24 h, 21 °C was determined to be the most effective as it utilized the least amount of KOH while generating 582.4 mg sugar/g raw biomass for a corresponding percent carbohydrate conversion of 91.8%.

Mixing Acid Salts and Layered Double Hydroxides in Nanoscale under Solid Condition.

Science.gov (United States)

Nakayama, Hirokazu; Hayashi, Aki

2014-07-30

The immobilization of potassium sorbate, potassium aspartate and sorbic acid in layered double hydroxide under solid condition was examined. By simply mixing two solids, immobilization of sorbate and aspartate in the interlayer space of nitrate-type layered double hydroxide, so called intercalation reaction, was achieved, and the uptakes, that is, the amount of immobilized salts and the interlayer distances of intercalation compounds were almost the same as those obtained in aqueous solution. However, no intercalation was achieved for sorbic acid. Although intercalation of sorbate and aspartate into chloride-type layered double hydroxide was possible, the uptakes for these intercalation compounds were lower than those obtained using nitrate-type layered double hydroxide. The intercalation under solid condition could be achieved to the same extent as for ion-exchange reaction in aqueous solution, and the reactivity was similar to that observed in aqueous solution. This method will enable the encapsulation of acidic drug in layered double hydroxide as nano level simply by mixing both solids.

Mixing Acid Salts and Layered Double Hydroxides in Nanoscale under Solid Condition

Directory of Open Access Journals (Sweden)

Hirokazu Nakayama

2014-07-01

Full Text Available The immobilization of potassium sorbate, potassium aspartate and sorbic acid in layered double hydroxide under solid condition was examined. By simply mixing two solids, immobilization of sorbate and aspartate in the interlayer space of nitrate-type layered double hydroxide, so called intercalation reaction, was achieved, and the uptakes, that is, the amount of immobilized salts and the interlayer distances of intercalation compounds were almost the same as those obtained in aqueous solution. However, no intercalation was achieved for sorbic acid. Although intercalation of sorbate and aspartate into chloride-type layered double hydroxide was possible, the uptakes for these intercalation compounds were lower than those obtained using nitrate-type layered double hydroxide. The intercalation under solid condition could be achieved to the same extent as for ion-exchange reaction in aqueous solution, and the reactivity was similar to that observed in aqueous solution. This method will enable the encapsulation of acidic drug in layered double hydroxide as nano level simply by mixing both solids.

Pretreatment of wheat straw with potassium hydroxide for increasing enzymatic and microbial degradability.

Science.gov (United States)

Liu, Xiaoying; Zicari, Steven M; Liu, Guangqing; Li, Yeqing; Zhang, Ruihong

2015-06-01

The pretreatment of wheat straw with potassium hydroxide (KOH) at ambient temperature (20°C) was investigated. The pretreatment effects on chemical composition and physical structures, and subsequent enzymatic hydrolysis and anaerobic digestion were evaluated. Wheat straw at 10% total solids (TS) was treated with KOH solution for 24h at a wide range of KOH loadings from 2% to 50% (w/w dry basis). Higher KOH loading resulted in higher lignin reduction from the straw and chemical oxygen demand (COD) in the resulting black liquor. Maximum lignin reduction of 54.7% was observed at 50% KOH loading. In comparison to untreated straw, specific hydrolysis yields achieved 14.0-92.3% over the range of 2-50% KOH loading, and methane yields increased 16.7-77.5% for KOH loadings of 10-50%, respectively. Accounting for losses during pretreatment, 20% KOH loading resulted in maximum overall reducing sugar yield and methane yield and therefore is the recommended loading for pretreatment under these conditions. Copyright © 2015 Elsevier Ltd. All rights reserved.

The in vitro antibacterial effect of iodine-potassium iodide and calcium hydroxide in infected dentinal tubules at different time intervals.

Science.gov (United States)

Lin, Shaul; Kfir, Anda; Laviv, Amir; Sela, Galit; Fuss, Zvi

2009-03-01

The aim of this study was to evaluate the antibacterial effect of iodine-potassium iodide (IKI) and calcium hydroxide (CH) on dentinal tubules infected with Enterococcus faecalis (E. faecalis) at different time intervals. Hollow cylinders of bovine root dentin (n=45) were infected and divided into three equal groups filled with either IKI or CH and a positive control. After placing each medicament in the infected cylinders for time periods of 10 minutes, 48 hours and 7 days, microbiological samples were analyzed. At the end of each period, four 100 microm thick inner dentin layers (400 microm thick from each specimen) were removed using dental burs of increasing diameters. Dentin powder was cultured on agar plates to quantitatively assess their infection, expressed in colony forming units (cfu). In all layers of the positive control group, heavy bacterial infection was observed. After 10 minutes, IKI reduced the amount of viable bacteria more efficiently than CH, whereas at later time intervals CH showed the best results. For short periods of exposure, IKI has a more efficient antibacterial effect in the dentinal tubules than CH but CH performs better after longer durations of exposure. This research indicates the use of IKI is a better choice for disinfecting the root canal than CH if only a short duration of exposure is used because of its more efficient antibacterial effect. However, if a longer exposure time is used, then CH is a better choice because of its better disinfecting effect over time.

Field effects in graphene in an interface contact with aqueous solutions of acetic acid and potassium hydroxide

Science.gov (United States)

Butko, A. V.; Butko, V. Yu.; Lebedev, S. P.; Lebedev, A. A.; Kumzerov, Yu. A.

2017-10-01

For the creation of new promising chemical sensors, it is very important to study the influence of the interface between graphene and aqueous solutions of acids and alkalis on the transistor characteristics of graphene. Transistor structures on the basis of graphene grown by thermal decomposition of silicon carbide were created and studied. For the interface of graphene with aqueous solutions of acetic acid and potassium hydroxide in the transistor geometry, with a variation in the gate-to-source voltage, the field effect corresponding to the hole type of charge carriers in graphene was observed. It is established that an increase in the concentration of molecular ions in these solutions leads to an increase in the dependence of the resistance of the transistor on the gate voltage.

Sudden bilateral sensorineural hearing loss as an unusual consequence of accidental ingestion of potassium hydroxide.

Science.gov (United States)

Ciorba, A; Bovo, R; Castiglione, A; Pirodda, A; Martini, A

2010-01-01

To discuss the possible etiopathogenetic mechanism of inner ear damage induced by the ingestion of potassium hydroxide (KOH). We report the case of a 37-year-old patient with sudden bilateral sensorineural hearing loss after accidental ingestion of a KOH solution. The first ear, nose and throat examination disclosed only mild edema of the upper airways. He was treated in the intensive care unit and prescribed high-dose steroids, proton pump inhibitors and sucralfate for 2 weeks. Unfortunately, there was no recovery of the hearing loss, and no audiogram changes were noticed after 12 months of follow-up. After exploring the possible etiopathogenetic mechanism involved, the authors believe that in this case, a transient severe hemodynamic imbalance can actually be considered to be the most reliable explanation for the inner ear damage and subsequent onset of permanent bilateral sensorineural hearing loss. Copyright 2010 S. Karger AG, Basel.

Removal of uranium and priority pollutant metals from Fernald Environmental Management Project wastewater utilizing potassium ferrate

International Nuclear Information System (INIS)

Hampshire, Lyle H.; Potts, Michael E.

1992-01-01

A side-by-side treatment comparison between calcium hydroxide and TRU/Clear '4', a potassium ferrate based wastewater treatment chemical, was performed in a process wastewater and stormwater treatment facility. Results from the full-scale plant testing demonstrated that potassium ferrate could achieve the same treatment levels as calcium hydroxide while generating 55% less sludge than the calcium hydroxide treatment. The testing also showed that utilization of potassium ferrate would minimize the volume of sludge generated and assist in the reduction of total waste management costs associated with storage, monitoring, transportation, and final disposition of generated sludge. (author)

Application of sorption method on hydroxides for purification of some reactive from iron(III) markings

International Nuclear Information System (INIS)

Rakhmonberdiev, A.D.; Khamidov, B.O.

1986-01-01

The method of purification of solutions of citric acid, tartaric acid and their salts, potassium hydroxide, potassium nitrate and chloride, sodium perchlorate from iron (III) impurities by means of sorption method on zirconium hydroxide is elaborated. The control of iron(III) content in solutions is conducted by inversion voltammetry method with mercury-graphite electrode. It is defined that complete sorption of iron (III) ions achieves at ph =4÷14.

Nickel-cobalt hydroxide nanosheets: Synthesis, morphology and electrochemical properties.

Science.gov (United States)

Schneiderová, Barbora; Demel, Jan; Zhigunov, Alexander; Bohuslav, Jan; Tarábková, Hana; Janda, Pavel; Lang, Kamil

2017-08-01

This paper reports the synthesis, characterization, and electrochemical performance of nickel-cobalt hydroxide nanosheets. The hydroxide nanosheets of approximately 0.7nm thickness were prepared by delamination of layered nickel-cobalt hydroxide lactate in water and formed transparent colloids that were stable for months. The nanosheets were deposited on highly oriented pyrolytic graphite by spin coating, and their electrochemical behavior was investigated by cyclic voltammetry in potassium hydroxide electrolyte. Our method of electrode preparation allows for studying the electrochemistry of nanosheets where the majority of the active centers can participate in the charge transfer reaction. The observed electrochemical response was ascribed to mutual compensation of the cobalt and nickel response via electron sharing between these metals in the hydroxide nanosheets, a process that differentiates the behavior of nickel-cobalt hydroxide nanosheets from single nickel hydroxide or cobalt hydroxide nanosheets or their physical mixture. The presence of cobalt in the nickel-cobalt hydroxide nanosheets apparently decreases the time of electrochemical activation of the nanosheet layer, which for the nickel hydroxide nanosheets alone requires more potential sweeps. Copyright © 2017 Elsevier Inc. All rights reserved.

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

Efficacy and tolerance of the topical application of potassium hydroxide (10% and 15%) in the treatment of molluscum contagiosum: randomized clinical trial: research protocol.

Science.gov (United States)

Marsal, Josep R; Cruz, Ines; Teixido, Concepcio; Diez, Olga; Martinez, Mireia; Galindo, Gisela; Real, Jordi; Schoenenberger, Joan A; Pera, Helena

2011-10-19

Molluscum contagiosum is a non-severe pediatric viral infection. Because it is highly contagious and current treatments have negative aesthetic and psychological effects, we want to test an alternative treatment in the primary care setting, consisting of two different concentrations of potassium hydroxide solution. The study design is a double-blind, randomized clinical trial, using three types of topical treatment. The treatment consist of daily applications of potassium hydroxide (KOH) in aqueous solution at 10% and 15% concentration, and a placebo administered in the control group. Four follow-up visits (at 15, 30, 45 and 60 days) are planned to evaluate treatment effectiveness and patient tolerance. The main outcome measure of the trial will be the healing rate, defined as lesion disappearance in the affected zones after the topic application of the experimental treatment. Secondary measures will be the principal characteristics and evolution of the affected zone (surface area, number of lesions, size and density of lesions), treatment tolerance (hyperpigmentation, itching, burning, pain), recurrence rate and the natural evolution of lesions in the control group. KOH can potentially be an effective and safe treatment for MC in primary care, and can also reduce referrals to dermatologists and hospital pediatric departments. In addition, KOH may be a valid and less expensive alternative to current invasive treatments (surgical excision).

Inhibiting and healing effects of potassium permanganate for silane films

Energy Technology Data Exchange (ETDEWEB)

She, Zuxin; Li, Qing, E-mail: liqingswu@yeah.net; Wang, Shaoyin; Luo, Fei; Chen, Funan; Li, Longqin

2013-07-31

In this study, the inhibiting and healing effects of potassium permanganate for silane films were investigated, and the optimal mole ratio of MnO{sub 4}{sup −}/Cl{sup −} was also obtained. The inhibiting process and healing mechanism were studied by electrochemical measurements and scanning electron microcopy coupled with energy dispersive spectroscopy. Results demonstrated that the introduction of potassium permanganate to electrolyte could stop the development of corrosion process and the optimal inhibiting mole ratio of MnO{sub 4}{sup −}/Cl{sup −} is 2 × 10{sup −1} with a protective efficiency about 99.24%. According to its high protective efficiency and the nice results of long-term immersion test, potassium permanganate as an inhibitor could prolong the lifetime of silane films and expand its scope of application. - Highlights: • Healing sol–gel film was obtained by adding KMnO{sub 4} into electrolyte. • An optimal inhibitor mole ratio of MnO{sub 4}{sup −}/Cl{sup −} for Si sol–gel was 2 × 10{sup −1}. • The best protective efficiency was approximately 99.24%. • The inhibiting effect may be due to production of insoluble manganese hydroxide/oxide.

Preparation of YBa2Cu3O7-x precursors from a fused eutectic of sodium and potassium hydroxides

International Nuclear Information System (INIS)

Coppa, N.; Nichols, D.H.; Schwegler, J.W.; Crow, J.E.; Myer, G.H.; Salamon, R.E.

1989-01-01

A method for preparing YBa 2 Cu 3 O 7-x from the simultaneous thermal decomposition of the nitrates of yttrium, barium, and copper in an anhydrous fused eutectic of sodium and potassium hydroxide is described. This method eliminates the need for any mechanical grinding or the introduction of carbon containing anions. Products formed are fine powders (∼1 μm) having mole ratios 1.00 Y:2.00 Ba:3.06 Cu. X-ray diffraction analysis reveal that the initial products are Y(OH) 3 , BaO 2 , and CuO, which when air calcinated/ oxygen annealed at 900--950 degree C form the superconducting YBa 2 Cu 3 O 7-x . A mechanism is postulated for product formation as a function of reaction conditions

Separation of valence forms of chromium(III) and chromium(VI) by coprecipitation with iron(III) hydroxide

International Nuclear Information System (INIS)

Nazirmadov, B.; Khamidov, B.O.; Egorova, L.A.

1989-01-01

The sorption of 9.62·10 -5 M of Cr (III) and Cr (VI) with iron hydroxide in 1 M potassium nitrate and potassium chloride was investigated in relation to the pH of the medium. Experimental data on the sorption of chromium(III) and chromium(VI) with iron(III) hydroxide made it possible to determine the region of practically complete concentration of Cr (III) and Cr (VI) (pH = 3-6.5). The results from spectrophotometric investigations, calculated data on the distribution of the hydroxocationic forms of chromium(III) and the anions of chromium(IV), and their sorption by iron-(III) hydroxide made it possible to characterize the sorbability of the cationic and anionic forms of chromium in various degrees of oxidation. On this basis a method was developed for the separation of chromium(III) and chromium(VI) by coprecipitation on iron(III) hydroxide and their separation from the iron(III) hydroxide support

Toxicity of tetramethylammonium hydroxide to aquatic organisms and its synergistic action with potassium iodide.

Science.gov (United States)

Mori, Izumi C; Arias-Barreiro, Carlos R; Koutsaftis, Apostolos; Ogo, Atsushi; Kawano, Tomonori; Yoshizuka, Kazuharu; Inayat-Hussain, Salmaan H; Aoyama, Isao

2015-02-01

The aquatic ecotoxicity of chemicals involved in the manufacturing process of thin film transistor liquid crystal displays was assessed with a battery of four selected acute toxicity bioassays. We focused on tetramethylammonium hydroxide (TMAH, CAS No. 75-59-2), a widely utilized etchant. The toxicity of TMAH was low when tested in the 72 h-algal growth inhibition test (Pseudokirchneriellia subcapitata, EC50=360 mg L(-1)) and the Microtox® test (Vibrio fischeri, IC50=6.4 g L(-1)). In contrast, the 24h-microcrustacean immobilization and the 96 h-fish mortality tests showed relatively higher toxicity (Daphnia magna, EC50=32 mg L(-1) and Oryzias latipes, LC50=154 mg L(-1)). Isobologram and mixture toxicity index analyses revealed apparent synergism of the mixture of TMAH and potassium iodide when examined with the D. magna immobilization test. The synergistic action was unique to iodide over other halide salts i.e. fluoride, chloride and bromide. Quaternary ammonium ions with longer alkyl chains such as tetraethylammonium and tetrabutylammonium were more toxic than TMAH in the D. magna immobilization test. Copyright © 2014 Elsevier Ltd. All rights reserved.

Efficacy and tolerance of the topical application of potassium hydroxide (10% and 15% in the treatment of molluscum contagiosum: Randomized clinical trial: Research protocol

Directory of Open Access Journals (Sweden)

Galindo Gisela

2011-10-01

Full Text Available Abstract Background Molluscum contagiosum is a non-severe pediatric viral infection. Because it is highly contagious and current treatments have negative aesthetic and psychological effects, we want to test an alternative treatment in the primary care setting, consisting of two different concentrations of potassium hydroxide solution. Methods/design The study design is a double-blind, randomized clinical trial, using three types of topical treatment. The treatment consist of daily applications of potassium hydroxide (KOH in aqueous solution at 10% and 15% concentration, and a placebo administered in the control group. Four follow-up visits (at 15, 30, 45 and 60 days are planned to evaluate treatment effectiveness and patient tolerance. The main outcome measure of the trial will be the healing rate, defined as lesion disappearance in the affected zones after the topic application of the experimental treatment. Secondary measures will be the principal characteristics and evolution of the affected zone (surface area, number of lesions, size and density of lesions, treatment tolerance (hyperpigmentation, itching, burning, pain, recurrence rate and the natural evolution of lesions in the control group. Discussion KOH can potentially be an effective and safe treatment for MC in primary care, and can also reduce referrals to dermatologists and hospital pediatric departments. In addition, KOH may be a valid and less expensive alternative to current invasive treatments (surgical excision. Trial Registration ClinicalTrials.gov: NCT01348386

Electronic spectra of anions intercalated in layered double hydroxides

Indian Academy of Sciences (India)

groups of the layers and interlayer water through the termi- nal atom symmetry ... results in a reaction with the metal hydroxide layers lead- ing to the ..... List of band positions observed for potassium salts of anion and LDH samples. Salts.

Graphene oxide/ferric hydroxide composites for efficient arsenate removal from drinking water

International Nuclear Information System (INIS)

Zhang Kai; Dwivedi, Vineet; Chi Chunyan; Wu Jishan

2010-01-01

A series of novel composites based on graphene oxide (GO) cross-linked with ferric hydroxide was developed for effective removal of arsenate from contaminated drinking water. GO, which was used as a supporting matrix here, was firstly treated with ferrous sulfate. Then, the ferrous compound cross-linked with GO was in situ oxidized to ferric compound by hydrogen peroxide, followed by treating with ammonium hydroxide. The morphology and composition of the composites were analyzed by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The ferric hydroxide was found to be homogenously impregnated onto GO sheets in amorphous form. These composites were evaluated as absorbents for arsenate removal from contaminated drinking water. For the water with arsenate concentration at 51.14 ppm, more than 95% of arsenate was absorbed by composite GO-Fe-5 with an absorption capacity of 23.78 mg arsenate/g of composite. Effective arsenate removal occurred in a wide range of pH from 4 to 9. However, the efficiency of arsenate removal was decreased when pH was increased to higher than 8.

Comparison of plain potassium hydroxide mounts, fungal cultures and nail plate biopsies in the diagnosis of onychomycosis

International Nuclear Information System (INIS)

Malik, N.A.; Nasiruddin, A.

2006-01-01

To compare the relative sensitivity of direct microscopy, fungal culture and nail plate biopsy in the diagnosis of onychomycosis. A total of 50 patients who were suffering from different clinical variants of onychomycosis, irrespective of their age, gender, with or without simultaneous presence of systemic diseases, were subjected to laboratory investigations including direct microscopy with 20% potassium hydroxide (KOH) for fungal hyphae, fungal cultures and nail plate biopsies. These patients were later categorized into two groups based upon the results of nail plate biopsies. Of 50 patients, 15 (30%) were positive for fungal elements in direct microscopy, 8 (16%) were positive for fungal culture and 16 (32%) revealed positive results in nail plate biopsies. Amongst nail plate biopsy positive cases, 10 (63%) were positive for direct microscopy and 6 (37.5%) were positive for fungal cultures. In biopsy negative cases, positive results for direct microscopy were seen in 5 (14.7%) patients and positive fungal culture was found in 2 (5.88%) patients. (author)

Splitting of 9-iodo-1,7-carborane by potassium hydroxide in butanol with butoxy group substitution for iodine atom when formation of anions of 1-butoxy- and 5-butoxy-nido-7,9-dicarbaundecaborate

International Nuclear Information System (INIS)

Zakharkin, L.I.; Ol'shevskaya, V.A.; Guseva, V.V.; Panfilova, S.Yu.

2000-01-01

The 9-iodo-1,7-carborane by heating in the potassium hydroxide butanol solution is splitted into the stereoisomeric anions of the nido-7,9-dicarbaundecaborate substituting under the reaction conditions the butoxy-group for iodine atom with formation of anions of the 1-butoxy- and -butoxy-nido-7,9-dicarbaundecaborate [ru

Practical tip: Chicago Sky Blue (CSB) stain can be added to the routine potassium hydroxide (KOH) wet-mount to provide a color contrast and facilitate the diagnosis of dermatomycoses.

Science.gov (United States)

Lim, Christopher Seng-Hong; Lim, Siew-Lin

2011-08-15

Rapid confirmation of dermatomycoses is desirable because it allows the clinician to initiate appropriate therapy without delay. The routine potassium hydroxide (KOH) wet-mount is cheap and rapid to use but this method lacks a color contrast. We offer a simple practical tip of adding Chicago Sky Blue (CSB) stain to KOH to highlight fungal elements and provide a color contrast that makes reading and interpretation simple, even for the novice.

Comparative study of Gram stain, potassium hydroxide smear, culture and nested PCR in the diagnosis of fungal keratitis.

Science.gov (United States)

Badiee, Parisa; Nejabat, Mahmood; Alborzi, Abdolvahab; Keshavarz, Fatemeh; Shakiba, Elaheh

2010-01-01

This study seeks to evaluate the efficacy and practicality of the molecular method, compared to the standard microbiological techniques for diagnosing fungal keratitis (FK). Patients with eye findings suspected of FK were enrolled for cornea sampling. Scrapings from the affected areas of the infected corneas were obtained and were divided into two parts: one for smears and cultures, and the other for nested PCR analysis. Of the 38 eyes, 28 were judged to have fungal infections based on clinical and positive findings in the culture, smear and responses to antifungal treatment. Potassium hydroxide, Gram staining, culture and nested PCR results (either positive or negative) matched in 76.3, 42.1, 68.4 and 81.6%, respectively. PCR is a sensitive method but due to the lack of sophisticated facilities in routine laboratory procedures, it can serve only complementarily and cannot replace conventional methods. Copyright © 2010 S. Karger AG, Basel.

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

Equilibrium studies on liquid ammonia-potassium amide-hydrogen system at high pressures and temperatures (Preprint No. CA-10)

International Nuclear Information System (INIS)

Donde, M.M.; Srinivasa, K.; Raman, S.

1989-04-01

Insoluble deposits were observed to form during the operation of Heavy Water Plant at Talcher, based on ammonia-hydrogen exchange process with potassium amide as catalyst. Experiments were undertaken to investigate this phenomenon under controlled conditions in the laboratory employing high pressures and elevated temperatures. It was observed that deposit formation was very minimal in the autoclave and no visible deposit was left on the strainer-filter, in all the experiments. Deposit analysis showed the presence of potassium hydroxide monohydrate as major component and alpha-potassium hydroxide and potassium azide as minor components. It is suggested that the presence of hydroxide may be due to the reaction of amide with the residual moisture in the system during the experiment and any ingress of moisture while opening for collection of deposit. Azide formation is explained by following reactions occurring during the experiments. NH 3 +KNH 2 →NH 2 -NH 2 +KH; NH 2 -NH 2 +KNH 2 →KN 3 +3H 2 . (author). 1 fig

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

The use of potassium hydroxide (KOH) solution as a suitable approach to isolate plastics ingested by marine organisms.

Science.gov (United States)

Kühn, Susanne; van Werven, Bernike; van Oyen, Albert; Meijboom, André; Bravo Rebolledo, Elisa L; van Franeker, Jan A

2017-02-15

In studies of plastic ingestion by marine wildlife, visual separation of plastic particles from gastrointestinal tracts or their dietary content can be challenging. Earlier studies have used solutions to dissolve organic materials leaving synthetic particles unaffected. However, insufficient tests have been conducted to ensure that different categories of consumer products partly degraded in the environment and/or in gastrointestinal tracts were not affected. In this study 63 synthetic materials and 11 other dietary items and non-plastic marine debris were tested. Irrespective of shape or preceding environmental history, most polymers resisted potassium hydroxide (KOH) solution, with the exceptions of cellulose acetate from cigarette filters, some biodegradable plastics and a single polyethylene sheet. Exposure of hard diet components and other marine debris showed variable results. In conclusion, the results confirm that usage of KOH solutions can be a useful approach in general quantitative studies of plastic ingestion by marine wildlife. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Cassava productivity linked to potassium's influence on water use efficiency

NARCIS (Netherlands)

Ezui, K.S.; Franke, A.C.; Leffelaar, P.A.; Giller, K.E.

2017-01-01

This paper presents the results of field studies conducted in Togo (Djakakope and Sevekpota) to assess the effect of potassium (K) on cassava yield, water use efficiency (WUE) and transpiration as affected by nitrogen (N) and phosphorus (P) availability under rainfed conditions. It was shown that an

High efficient photocatalytic activity of Zn-Al-Ti layered double hydroxides nanocomposite

Directory of Open Access Journals (Sweden)

Amor F.

2018-01-01

Full Text Available This work establishes a simple method for synthesising layered double hydroxides (LDHs powders with coprecipitation. The characteristics of the samples were investigated y X-ray diffraction (XRD, scanning electron microscopy (SEM and spectrophotometer UV–Vis (DRS. Non-uniform distribution was shown for LDHs samples by SEM. Photocatalytic efficiencies were tested using methylene blue (MB dye as a model contaminant under UV irradiation. In particular, Zn–Al-Ti LDH exhibited an excellent performance towards MB degradation compared with commercial TiO2 nanoparticles. Methylene blue removal percentage was reached at almost 100%, whereas commercial TiO2 reached a removal rate of only 66% under the same conditions within 20 min. The aim of the current work is to prepare Zn-Al-Ti layered double hydroxides nanocomposite and to evaluate their photocatalytic activity in the removal of methylene blue under UV irradiation.

Electron impact study of potassium hydroxide

Science.gov (United States)

Vuskovic, L.; Trajmar, S.

1979-01-01

An attempt is made to measure the sum of the elastic, rotational and vibrational scattering of electrons by KOH at low impact energies (5 to 20 eV) at angles from 10 to 120 deg. Energy loss spectra taken in the 0 to 18 eV range using an electron impact spectrometer are used to identify the species contributing to electric scattering. At temperatures between 300 and 500 C, only inelastic spectral features belonging to water are detected, while at temperatures from 500 to 800 C strong atomic K lines, indicative of molecular dissociation, and H2 energy loss features become prominent. No features attributable to KOH, the KOH dimer, O2 or potassium oxides were observed, due to the effects of the dissociation products, and it is concluded that another technique will have to be developed in order to measure electron scattering by KOH.

Enhancing methane production of corn stover through a novel way: sequent pretreatment of potassium hydroxide and steam explosion.

Science.gov (United States)

Li, Jianghao; Zhang, Ruihong; Siddhu, Muhammad Abdul Hanan; He, Yanfeng; Wang, Wen; Li, Yeqing; Chen, Chang; Liu, Guangqing

2015-04-01

Getting over recalcitrance of lignocellulose is effective way to fuel production from lignocellulosic biomass. In current work, different pretreatments were applied to enhance the digestibility of corn stover (CS). Results showed that steam explosion (SE)-treated CS produced maximal methane yield (223.2 mL/gvs) at 1.2 MPa for 10 min, which was 55.2% more than untreated (143.8 mL/gvs). Whereas 1.5% KOH-treated CS produced maximum methane yield of 208.6 mL/gvs, and significantly (αpotassium hydroxide and steam explosion (SPPE) (1.5% KOH-1.2 MPa, 10 min) achieved a very significant (α<0.01) improvement (80.0%) of methane yield (258.8 mL/gvs) compared with untreated CS. Methane production could be well explained by the first-order and modified Gompertz models. Besides, SEM, FTIR, and XRD analyses validated structural changes of CS after SPPE. SPPE might be a promising method to pretreat CS in the future AD industry. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of topical potassium hydroxide solution for treatment of plane warts.

Science.gov (United States)

Al-Hamdi, Khalil I; Al-Rahmani, Moutaz A A

2012-01-01

Plane wart is a common dermatological disease that is caused by human papilloma virus; although the rate of spontaneous recovery is high, it usually takes a long time to occur. Many modalities of treatments have been used but none of them proved to be uniformly effective. Potassium hydroxide (KOH) solution is a well-known keratolytic agent with many dermatological uses. To evaluate the efficacy and tolerability of topical KOH solution in the treatment of plane warts. A total of 250 patients with plane warts, consulting the department of Dermatology and Venereology of Basra Teaching Hospital between March 2008 and October 2009, were enrolled in this opened therapeutic trial study. Patients were divided into two age and sex cross-matched equal groups; patients in group (A) were treated with topical 5% KOH solution once at night, while patients in group (B) were treated with topical 10% KOH solution once nightly. Only 107 patients from group (A) and 95 patients from group (B) completed the study, while the remainders were defaulted for unknown reasons. The patients were evaluated at second and fourth week to assess the cure rates and side effects, those patients who showed complete cure were followed up for 3 months to detect any recurrence. At the end of second week, 9.3% of group (A) patients showed complete disappearance of their warts, vs 66.3% of group (B) patients. At the end of fourth week, 80.3% of group (A) patients showed complete response in comparison with 82.1% of group (B) patients. The side effects for the treating solution in both concentrations include itching, burning sensation, erythema, and temporary dyspigmentations, that were reported in 77.6% of group (A) patients in comparison with 90.5% of group (B) patients. Recurrence rate was reported in 5.8% of group (A) patients vs 5.1% of group (B) patients during the three months period of follow-up. Topical KOH solution is proved to be an effective and safe treatment of plane warts in both

Synthetic Applications and Mechanistic Studies of the Hydroxide-Mediated Cleavage of Carbon-Carbon Bonds in Ketones

DEFF Research Database (Denmark)

Mazziotta, Andrea; Makarov, Ilya S.; Fristrup, Peter

2017-01-01

The hydroxide-mediated cleavage of ketones into alkanes and carboxylic acids has been reinvestigated and the substrate scope extended to benzyl carbonyl compounds. The transformation is performed with a 0.05 M ketone solution in refluxing xylene in the presence of 10 equiv of potassium hydroxide....... The studies were complemented by a theoretical investigation where two possible pathways were characterized by DFT/M06-2X. The calculations showed that the scission takes place by nucleophilic attack of hydroxide on the ketone followed by fragmentation of the resulting oxyanion into the carboxylic acid...

Aluminum Hydroxide and Magnesium Hydroxide

Science.gov (United States)

Aluminum Hydroxide, Magnesium Hydroxide are antacids used together to relieve heartburn, acid indigestion, and upset stomach. They ... They combine with stomach acid and neutralize it. Aluminum Hydroxide, Magnesium Hydroxide are available without a prescription. ...

The effects of lithium hydroxide solution on alkali silica reaction gels created with opal

International Nuclear Information System (INIS)

Mitchell, Lyndon D.; Beaudoin, James J.; Grattan-Bellew, Patrick

2004-01-01

The reaction of Nevada opal with calcium hydroxide, potassium hydroxide and lithium hydroxide solutions was investigated. In addition, opal was exposed to a combined solution of these three hydroxides. The progress of the three reactions was followed using X-ray diffraction (XRD), 29 Si nuclear magnetic resonance (NMR) and scanning electron microscopy (SEM). The XRD results indicated the presence of a low-angle peak exclusive to the lithium-based reactions. The NMR results suggested a change in the silicate structure in the presence of lithium. These techniques indicated that the reaction of the alkali with the opal starting material is inhibited and perhaps stopped in the presence of lithium hydroxide. SEM revealed that the morphology of the reaction products on the surface of the reacted opal grains is markedly different invariably. It was concluded that evidence to support the theory of a protective layer exists and that the nature of the layer varies with ion type

Evaluation of topical potassium hydroxide solution for treatment of plane warts

Directory of Open Access Journals (Sweden)

Khalil I Al-Hamdi

2012-01-01

Full Text Available Background: Plane wart is a common dermatological disease that is caused by human papilloma virus; although the rate of spontaneous recovery is high, it usually takes a long time to occur. Many modalities of treatments have been used but none of them proved to be uniformly effective. Potassium hydroxide (KOH solution is a well-known keratolytic agent with many dermatological uses. Objective: To evaluate the efficacy and tolerability of topical KOH solution in the treatment of plane warts. Materials and Methods: A total of 250 patients with plane warts, consulting the department of Dermatology and Venereology of Basra Teaching Hospital between March 2008 and October 2009, were enrolled in this opened therapeutic trial study. Patients were divided into two age and sex cross-matched equal groups; patients in group (A were treated with topical 5% KOH solution once at night, while patients in group (B were treated with topical 10% KOH solution once nightly. Only 107 patients from group (A and 95 patients from group (B completed the study, while the remainders were defaulted for unknown reasons. The patients were evaluated at second and fourth week to assess the cure rates and side effects, those patients who showed complete cure were followed up for 3 months to detect any recurrence. Results: At the end of second week, 9.3% of group (A patients showed complete disappearance of their warts, vs 66.3% of group (B patients. At the end of fourth week, 80.3% of group (A patients showed complete response in comparison with 82.1% of group (B patients. The side effects for the treating solution in both concentrations include itching, burning sensation, erythema, and temporary dyspigmentations, that were reported in 77.6% of group (A patients in comparison with 90.5% of group (B patients. Recurrence rate was reported in 5.8% of group (A patients vs 5.1% of group (B patients during the three months period of follow-up. Conclusions: Topical KOH solution is

Concentration of 99Tc in seawater by coprecipitation with iron hydroxide

International Nuclear Information System (INIS)

Momoshima, Noriyuki; Eto, Ichiro; Muhammad Sayad; Takashima, Yoshimasa

1991-01-01

A method for accumulation of 99 Tc in seawater has been developed. Technetium tracer in +VII oxidation state was added to the seawater together with reducing agent, potassium pyrosulfite, and coprecipitation agent, ferric chloride. After reduction of Tc(VII) at pH 4, Tc(IV) was coprecipitated as iron hydroxide by addition of sodium hydroxide to pH 9. The reduction and coprecipitation was quantitative and overall recovery of Tc was more than 98%. The green color of iron precipitate formed at pH 9 suggested that Tc(VII) as well as ferric ion was reduced under this condition. Adsorption of Tc(IV), however, was poor for iron hydroxide which was prepared in advance indicating active surface of freshly precipitated iron hydroxide is necessary for quantitative recovery of Tc(IV). A repeating coprecipitation technique was examined for enrichment of Tc in seawater that the same iron was used repeatedly as coprecipitater. After separation of iron hydroxide with Tc(IV) from supernatant, the precipitate was dissolved by addition of acid and then new seawater which contained reducing agent and Tc(VII) was added. Reduction and coprecipitation was again carried out. Good recovery was attained for 7 repeats. The proposed repeating coprecipitation technique was applicable to a large amount of seawater without increasing the amount of iron hydroxide which is subjected to radiochemical analysis. (author)

Comparison of plain potassium hydroxide mounts, fungal cultures and nail plate biopsies in the diagnosis of onychomycosis.

Science.gov (United States)

Malik, Naveed Akhter; Nasiruddin; Dar, Nasser Rasheed; Khan, Ashfaq Ahmed

2006-10-01

To compare the relative sensitivity of direct microscopy, fungal culture and nail plate biopsy in the diagnosis of onychomycosis. Cross-sectional study. The Skin Department, Military Hospital, Rawalpindi from February 1998 to February 1999. A total of 50 patients who were suffering from different clinical variants of onychomycosis, irrespective of their age, gender, with or without simultaneous presence of systemic diseases, were subjected to laboratory investigations including direct microscopy with 20% potassium hydroxide (KOH) for fungal hyphae, fungal cultures and nail plate biopsies. These patients were later categorized into two groups based upon the results of nail plate biopsies. Of 50 patients, 15 (30%) were positive for fungal elements in direct microscopy, 8 (16%) were positive for fungal culture and 16 (32%) revealed positive results in nail plate biopsies. Amongst nail plate biopsy positive cases, 10 (63%) were positive for direct microscopy and 6 (37.5%) were positive for fungal cultures. In biopsy negative cases, positive results for direct microscopy were seen in 5 (14.7%) patients and positive fungal culture was found in 2 (5.88%) patients. The clinical impression of onychomycosis is not true in all the cases. Nail scraping for direct microscopy with 20% KOH should be the first line screening test for all patients which should then be supplemented with fungal culture and/ or nail plate biopsy.

Synthetic Applications and Mechanistic Studies of the Hydroxide-Mediated Cleavage of Carbon-Carbon Bonds in Ketones

DEFF Research Database (Denmark)

Mazziotta, Andrea; Makarov, Ilya S.; Fristrup, Peter

2017-01-01

The hydroxide-mediated cleavage of ketones into alkanes and carboxylic acids has been reinvestigated and the substrate scope extended to benzyl carbonyl compounds. The transformation is performed with a 0.05 M ketone solution in refluxing xylene in the presence of 10 equiv of potassium hydroxide....... The reaction constitutes a straightforward protocol for the synthesis of certain phenyl-substituted carboxylic acids from 2-phenylcycloalkanones. The mechanism was investigated by kinetic experiments which indicated a first order reaction in hydroxide and a full negative charge in the rate-determining step....... The studies were complemented by a theoretical investigation where two possible pathways were characterized by DFT/M06-2X. The calculations showed that the scission takes place by nucleophilic attack of hydroxide on the ketone followed by fragmentation of the resulting oxyanion into the carboxylic acid...

Synthetic Applications and Mechanistic Studies of the Hydroxide-Mediated Cleavage of Carbon-Carbon Bonds in Ketones.

Science.gov (United States)

Mazziotta, Andrea; Makarov, Ilya S; Fristrup, Peter; Madsen, Robert

2017-06-02

The hydroxide-mediated cleavage of ketones into alkanes and carboxylic acids has been reinvestigated and the substrate scope extended to benzyl carbonyl compounds. The transformation is performed with a 0.05 M ketone solution in refluxing xylene in the presence of 10 equiv of potassium hydroxide. The reaction constitutes a straightforward protocol for the synthesis of certain phenyl-substituted carboxylic acids from 2-phenylcycloalkanones. The mechanism was investigated by kinetic experiments which indicated a first order reaction in hydroxide and a full negative charge in the rate-determining step. The studies were complemented by a theoretical investigation where two possible pathways were characterized by DFT/M06-2X. The calculations showed that the scission takes place by nucleophilic attack of hydroxide on the ketone followed by fragmentation of the resulting oxyanion into the carboxylic acid and a benzyl anion.

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

New type ternary NiAlCe layered double hydroxide photocatalyst for efficient visible-light photoreduction of CO2 into CH4

Science.gov (United States)

Li, Ji; (Bill Yang, Y. J.

2018-02-01

New type of ternary NiAlCe layered double hydroxide photocatalyst was synthesized by a simple hydrothermal reaction. The obtained photocatalyst shows efficient visible-light activity for CO2 reduction to CH4. We have investigated the optimal Ce content in the catalyst and analyzed the mechanism by materials characterization. Additionally, a novel alkali etching method was used to construct the porous structure. The effect of the porosity and morphologies on the activity is investigated. It is found that the ternary NiAlCe layered double hydroxide photocatalyst with porosity showing the best photocatalytic activity among all the samples. Based on the characterization and first principle calculation, the detailed photocatalytic mechanism of the ternary NiAlCe layered double hydroxide photocatalyst is deduced.

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

Comparison of 10% potassium hydroxide solution versus cryotherapy in the treatment of molluscum contagiosum: an open randomized clinical trial.

Science.gov (United States)

Handjani, Farhad; Behazin, Ebrahim; Sadati, Maryam Sadat

2014-06-01

Molluscum contagiosum (MC) is a common cutaneous viral infection. Potassium hydroxide (KOH), as a strong alkali, and cryotherapy have been used for its treatment. The objective of this study was to compare these two treatment modalities. 30 patients, aged between 1 and 24 years of age, were randomly divided into 2 groups: 15 were treated with KOH 10% solution and 15 were treated with cryotherapy. KOH 10 % was applied by the patient or their parent(s) two times a day until the lesions disappeared completely. Cryotherapy was performed with liquid nitrogen spray, repeated weekly for 4 weeks. The assessment of response and side effects were performed weekly for 4 weeks. In the KOH group, 86.6% had complete response, 6.7% had partial response and 6.7% had no response after 4 weeks. In the cryotherapy group, 93.3% had complete response and 6.7% had partial response. There was no statistically significant difference between the two groups (p > 0.05). Postinflammatory hyperpigmentation, as a side effect, was mostly noted with cryotherapy. Both treatment modalities were equally effective. Since KOH is inexpensive and confers better cosmetic results compared to cryotherapy, it can be used as a suitable treatment modality for MC.

Controlling electrodeposited ultrathin amorphous Fe hydroxides film on V-doped nickel sulfide nanowires as efficient electrocatalyst for water oxidation

Science.gov (United States)

Shang, Xiao; Yan, Kai-Li; Lu, Shan-Shan; Dong, Bin; Gao, Wen-Kun; Chi, Jing-Qi; Liu, Zi-Zhang; Chai, Yong-Ming; Liu, Chen-Guang

2017-09-01

Developing cost-effective electrocatalysts with both high activity and stability remains challenging for oxygen evolution reaction (OER) in water electrolysis. Herein, based on V-doped nickel sulfide nanowire on nickel foam (NiVS/NF), we further conduct controllable electrodeposition of Fe hydroxides film on NiVS/NF (eFe/NiVS/NF) to further improve OER performance and stability. For comparison, ultrafast chemical deposition of Fe hydroxides on NiVS/NF (uFe/NiVS/NF) is also utilized. V-doping of NiVS/NF may introduce more active sites for OER, and nanowire structure can expose abundant active sites and facilitate mass transport. Both of the two depositions generate amorphous Fe hydroxides film covering on the surface of nanowires and lead to enhanced OER activities. Furthermore, electrodeposition strategy realizes uniform Fe hydroxides film on eFe/NiVS/NF confirmed by superior OER activity of eFe/NiVS/NF than uFe/NiVS/NF with relatively enhanced stability. The OER activity of eFe/NiVS/NF depends on various electrodepositon time, and the optimal time (15 s) is obtained with maximum OER activity. Therefore, the controllable electrodeposition of Fe may provide an efficient and simple strategy to enhance the OER properties of electrocatalysts.

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.

Sodium Hydroxide and Calcium Hydroxide Hybrid Oxygen Bleaching with System

Science.gov (United States)

Doelle, K.; Bajrami, B.

2018-01-01

This study investigates the replacement of sodium hydroxide in the oxygen bleaching stage using a hybrid system consisting of sodium hydroxide calcium hydroxide. Commercial Kraft pulping was studied using yellow pine Kraft pulp obtained from a company in the US. The impact of sodium hydroxide, calcium hydroxide hybrid system in regard to concentration, reaction time and temperature for Kraft pulp was evaluated. The sodium hydroxide and calcium hydroxide dosage was varied between 0% and 15% based on oven dry fiber content. The bleaching reaction time was varied between 0 and 180 minutes whereas the bleaching temperature ranged between 70 °C and 110 °C. The ability to bleach pulp was measured by determining the Kappa number. Optimum bleaching results for the hybrid system were achieved with 4% sodium hydroxide and 2% calcium hydroxide content. Beyond this, the ability to bleach pulp decreased.

A concise route to branched erythrono-gamma-lactones. Synthesis of the leaf-closing substance potassium (+/-)-(2R,3R)-2,3,4-trihydroxy-2-methylbutanoate

DEFF Research Database (Denmark)

Pedersen, Daniel Sejer; Robinson, Tony V; Taylor, Dennis K

2009-01-01

-94% yield), including the natural plant lactone (+/-)-2-C-d-methylerythrono-1,4-lactone 1. The latter compound was treated with aqueous potassium hydroxide to afford potassium (+/-)-(2R,3R)-2,3,4-trihydroxy-2-methylbutanoate 2, which is a leaf-closing substance of Leucaena leucocephalam....

Effects of adhesions of amorphous Fe and Al hydroxides on surface charge and adsorption of K+ and Cd2+ on rice roots.

Science.gov (United States)

Liu, Zhao-Dong; Wang, Hai-Cui; Zhou, Qin; Xu, Ren-Kou

2017-11-01

Iron (Fe) and aluminum (Al) hydroxides in variable charge soils attached to rice roots may affect surface-charge properties and subsequently the adsorption and uptake of nutrients and toxic metals by the roots. Adhesion of amorphous Fe and Al hydroxides onto rice roots and their effects on zeta potential of roots and adsorption of potassium (K + ) and cadmium (Cd 2+ ) by roots were investigated. Rice roots adsorbed more Al hydroxide than Fe hydroxide because of the greater positive charge on Al hydroxide. Adhesion of Fe and Al hydroxides decreased the negative charge on rice roots, and a greater effect of the Al hydroxide. Consequently, adhesion of Fe and Al hydroxides reduced the K + and Cd 2+ adsorption by rice roots. The results of attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and desorption of K + and Cd 2+ from rice roots indicated that physical masking by Fe and Al hydroxides and diffuse-layer overlapping between the positively-charged hydroxides and negatively-charged roots were responsible for the reduction of negative charge on roots induced by adhesion of the hydroxides. Therefore, the interaction between Fe and Al hydroxides and rice roots reduced negative charge on roots and thus inhibited their adsorption of nutrient and toxic cations. Copyright © 2017 Elsevier Inc. All rights reserved.

The effectiveness of sodium hydroxide (NaOH) and sodium carbonate (Na2CO3) on the impurities removal of saturated salt solution

Science.gov (United States)

Pujiastuti, C.; Ngatilah, Y.; Sumada, K.; Muljani, S.

2018-01-01

Increasing the quality of salt can be done through various methods such as washing (hydro-extraction), re-crystallization, ion exchange methods and others. In the process of salt quality improvement by re-crystallization method where salt product diluted with water to form saturated solution and re-crystallized through heating process. The quality of the salt produced is influenced by the quality of the dissolved salt and the crystallization mechanism applied. In this research is proposed a concept that before the saturated salt solution is recrystallized added a chemical for removal of the impurities such as magnesium ion (Mg), calcium (Ca), potassium (K) and sulfate (SO4) is contained in a saturated salt solution. The chemical reagents that used are sodium hydroxide (NaOH) 2 N and sodium carbonate (Na2CO3) 2 N. This research aims to study effectiveness of sodium hydroxide and sodium carbonate on the impurities removal of magnesium (Mg), calcium (Ca), potassium (K) and sulfate (SO4). The results showed that the addition of sodium hydroxide solution can be decreased the impurity ions of magnesium (Mg) 95.2%, calcium ion (Ca) 45%, while the addition of sodium carbonate solution can decreased magnesium ion (Mg) 66.67% and calcium ion (Ca) 77.5%, but both types of materials are not degradable sulfate ions (SO4). The sodium hydroxide solution more effective to decrease magnesium ion than sodium carbonate solution, and the sodium carbonate solution more effective to decrease calcium ion than sodium hydroxide solution.

Promotion Effect of Alkali Metal Hydroxides on Polymer-Stabilized Pd Nanoparticles for Selective Hydrogenation of C–C Triple Bonds in Alkynols

OpenAIRE

Nikoshvili, Linda Zh.; Bykov, Alexey V.; Khudyakova, Tatiana E.; Lagrange, Thomas; Héroguel, Florent; Luterbacher, Jeremy S.; Matveeva, Valentina G.; Sulman, Esther M.; Dyson, Paul J.; Kiwi-Minsker, Lioubov

2017-01-01

Postimpregnation of Pd nanoparticles (NPs) stabilized within hyper-cross-linked polystyrene with sodium or potassium hydroxides of optimal concentration was found to significantly increase the catalytic activity for the partial hydrogenation of the C–C triple bond in 2-methyl-3-butyn-2-ol at ambient hydrogen pressure. The alkali metal hydroxide accelerates the transformation of the residual Pd(II) salt into Pd(0) NPs and diminishes the reaction induction period. In addition, the selectivity t...

Application of magnesium hydroxide and barium hydroxide for the ...

African Journals Online (AJOL)

Application of magnesium hydroxide and barium hydroxide for the removal of metals and sulphate from mine water. ... equivalent to the Ba(OH)2 dosage. During CO2-dosing, CaCO3 is precipitated to the saturation level of CaCO3. Keywords: Magnesium hydroxide; barium hydroxide; sulphate removal; water treatment ...

Antimicrobial activity of potassium hydroxide and lauric acid against microorganisms associated with poultry processing.

Science.gov (United States)

Hinton, Arthur; Ingram, Kimberly D

2006-07-01

The antimicrobial activity of solutions of potassium hydroxide (KOH) and mixtures of KOH and lauric acid against microorganisms associated with poultry processing was determined. In vitro tests were performed by enumerating viable microorganisms recovered from bacterial cultures suspended in peptone water (control) and in solutions of 0.1% KOH or mixtures of 0.1% KOH and 0.25 or 0.50% lauric acid. Additional studies were conducted to identify changes in the native microbial flora of poultry skin washed in distilled water, KOH, or KOH-lauric acid. Although results of in vitro studies indicated that significantly fewer bacteria (P < or = 0.05) were recovered from cultures suspended in KOH than from cultures suspended in peptone water, there were also significantly fewer bacteria recovered from cultures suspended in KOH-lauric acid than from cultures suspended in KOH. Results of experiments with broiler skin indicated that although rinsates of skin washed in 1.0% KOH solutions contained significantly fewer total aerobic bacteria and enterococci than did skin washed in water, significantly fewer of these microorganisms were generally recovered from rinsates of skin washed in mixtures of 1.0% KOH and 0.5, 1.0, 1.5, or 2.0% lauric acid than from skin washed in KOH alone. Washing of broiler skin in solutions of 0.25 to 1.00% KOH or mixtures containing these concentrations of KOH and two parts lauric acid (wt/vol) also significantly reduced the populations of bacteria and yeasts in the native flora of broiler skin. Enterococci, lactic acid bacteria, and staphylococci in the native flora of the skin had the highest level of resistance to the bactericidal activity of KOH-lauric acid. These findings indicate that the antimicrobial activity of KOH-lauric acid is significantly greater than that of KOH alone in vitro and on poultry skin. Thus, KOH-lauric acid may be useful for reducing the level of microbial contamination associated with poultry processing.

Biosorption of copper(II) and lead(II) onto potassium hydroxide treated pine cone powder.

Science.gov (United States)

Ofomaja, A E; Naidoo, E B; Modise, S J

2010-08-01

Pine cone powder surface was treated with potassium hydroxide and applied for copper(II) and lead(II) removal from solution. Isotherm experiments and desorption tests were conducted and kinetic analysis was performed with increasing temperatures. As solution pH increased, the biosorption capacity and the change in hydrogen ion concentration in solution increased. The change in hydrogen ion concentration for lead(II) biosorption was slightly higher than for copper(II) biosorption. The results revealed that ion-exchange is the main mechanism for biosorption for both metal ions. The pseudo-first order kinetic model was unable to describe the biosorption process throughout the effective biosorption period while the modified pseudo-first order kinetics gave a better fit but could not predict the experimentally observed equilibrium capacities. The pseudo-second order kinetics gave a better fit to the experimental data over the temperature range from 291 to 347 K and the equilibrium capacity increased from 15.73 to 19.22 mg g(-1) for copper(II) and from 23.74 to 26.27 for lead(II). Activation energy was higher for lead(II) (22.40 kJ mol(-1)) than for copper(II) (20.36 kJ mol(-1)). The free energy of activation was higher for lead(II) than for copper(II) and the values of DeltaH* and DeltaS* indicate that the contribution of reorientation to the activation stage is higher for lead(II) than copper(II). This implies that lead(II) biosorption is more spontaneous than copper(II) biosorption. Equilibrium studies showed that the Langmuir isotherm gave a better fit for the equilibrium data indicating monolayer coverage of the biosorbent surface. There was only a small interaction between metal ions when simultaneously biosorbed and cation competition was higher for the Cu-Pb system than for the Pb-Cu system. Desorption studies and the Dubinin-Radushkevich isotherm and energy parameter, E, also support the ion-exchange mechanism. Copyright 2010 Elsevier Ltd. All rights reserved.

Comparative Evaluation of Topical 10% Potassium Hydroxide and 30% Trichloroacetic Acid in the Treatment of Plane Warts.

Science.gov (United States)

Jayaprasad, Sandhaya; Subramaniyan, Radhakrishnan; Devgan, Shalini

2016-01-01

Warts are benign proliferations of skin and mucosa caused by the human papillomavirus (HPV). Plane warts are caused by HPV types 3, 10, 28, and 41, occurring mostly in children and young adults. Among the treatment modalities, topical application of trichloroacetic acid (TCA) is age old. Potassium hydroxide (KOH) has a keratolytic effect on virus-infected cells. It is less irritating, less painful, less scar forming, and can be safely used in children too. Hence, it could be a better topical agent in the treatment of plane warts. To compare the safety and efficacy of topical 10% KOH with 30% TCA in the treatment of plane warts. Sixty consecutive patients with plane warts were randomly assigned into two arms of thirty patients each; arm A received topical 10% KOH and arm B received topical 30% TCA as a once weekly application until the complete clearance of warts or a maximum period of 12 weeks. Statistically no significant difference ( P = 0.07) was found between the objective therapeutic response to 10% KOH and 30% TCA at the end of study (12 weeks). However, subjective response to 10% KOH was better and statistically significant ( P = 0.03). There was no recurrence of warts seen on follow-up for 3 months of complete responders in both the arms. 10% KOH is found to be equally effective in the treatment of plane warts compared to 30% TCA with the advantage of faster onset of action and tendency of completely clearing warts with fewer side effects.

Effect of different rates of potassium fertilizer and soil moisture on nitrogen and potassium use efficiencies and tomato yield using an 15N isotopic dilution technique

International Nuclear Information System (INIS)

Khalifa, Kh.; Al-Ain, F.; Al-Chamma'a, M.

2005-03-01

A pot experiment was conducted to evaluate the response of tomato to 4 potassium rates (0, 90, 120, 150 kg K 2 O/ha), one rate of N (150 kg/ha) and two irrigation regimes 65 % and 85 % of field capacity (FC) on yield and the efficient use of N and K fertilizers. Results showed that dry matter yield was positively correlated with the rate of K fertilizer applied under the two irrigation regimes. However the increase in production of fruits and dry matter was higher at the 85% FC. The K-uptake in fruit and whole plant increased with increasing K application levels and was higher at the 85 % but the opposite was observed in shoots and roots. Potassium use efficiency increased with increasing K levels at the two irrigation regimes and the values were higher at the 85 %. The nitrogen use efficiency in shoots, roots , fruits and the whole plant increased with increasing K levels and was highest at the 85 % FC and 150 kg K 2 O/ ha fertilizer rate. (Authors)

The Investigation of Electron Beam Catalytical Oxidation Process Efficiency with Potassium Persulfate in Removal Humic Acid from Aqueous Solutions

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MT Ghaneian

2015-05-01

Results: Based on the results, changes in pH had little effect on the Humic acid removal efficiency. The average, with increasing of pH from 4 to 10, the removal efficiency of humic acid from 72.59% to 73.36% increased, respectively. The results showed that increasing of the dose from 1 to 15 kGy, humic acid removal efficiency increases. Based on results by increasing of persulfate concentration, the removal efficiency increased so that with increasing of concentration of potassium persulfate from 0.1 to 0.5 mmol/100cc, removal efficiency from 69.43% to 83.82% was increased. Kinetic experiments showed that the decomposition of humic acid by electron beam radiation followed the second-order kinetic. Conclusion: The data from this study showed that the aqueous solution containing acid Humic is decomposed effectively by electron beams irradiation. Addition of potassium persulfate can be have significant improvements in removal efficiency of humic acid in the presence of electron beam.

Effect of different rates of potassium fertilizer on nitrogen use efficiency and cotton yield using an 15N isotopic dilution technique

International Nuclear Information System (INIS)

Khalifa, Kh.; Al-Chamma'a, M.; Al-Ain, F.

2005-03-01

A field study was carried out during the 2003 growing season on a loamy to sandy clay loamy soil, located at the Lower Euphrate's Valley, 15 km southeast of Deir - Ezzor city to evaluate the effect of K fertilizer on nitrogen , potassium use efficiency and cotton yield. Three nitrogen ( N1 =120, N2 =180, and N3 = 240 kg N / ha ) and four potassium application rates ( K0 = 0 , K1 = 50, K2 = 100, K3 = 150 kg K2O / ha ) were employed. The cotton variety was Deir 22 sown on April 2003 at a spacing of 70 cm between rows and 20 cm between pits with 5 seeds per pit. The plants were thinned to 2 plants per pit 4 weeks after planting. Representative samples of aboveground portions of cotton plants were harvested from labeled subplots at 108 and 161 days after planting . Dry matter weight , N uptake, N fertilizer yield, N use efficiency, K use efficiency, seed cotton yield, earliness, leaf area, number of bolls / plant, and number of branches / plant were evaluated. The results showed that seed cotton yield increased with increasing K levels applied under each rate of N ( except N120 ). The highest seed cotton yield was obtained with the combined treatment N3K1 ( 6442 kg/ha ). This treatment gave also the optimum potassium use efficiency ( 42 % ). Nitrogen use efficiency (at 180 days of harvest ) increased with the increasing K application rate. Nitrogen use efficiency (NUE) was decreased with increasing N rates . Increasing K application rate ( KUE ) decreased potassium use efficiency. A maximum N use efficiency ( 98% ) was obtained for combined treatment N2 K3. Also the results indicated that dry matter weight and N uptake increased with increasing K rates applied. Nitrogen derived from fertilizer (Ndff ) was higher in combined treatments than the control treatments (K0 ). (Authors)

Preparation of High specific activity of ''51 Cr by the Szilard-Chalmers effect on potassium chromate

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Barrachina Gomez, M; Villar Castejon, M A

1965-07-01

The {sup 5}1 Cr enriched Cr{sup 3}+ ions, which appear on putting into solution the potassium chromate irradiated with neutrons, are separated as chromium hydroxide. The CrO{sub 4}{sup 2}- ions occluded by the precipitate are eliminated on re precipitating the hydroxide. The more convenient irradiation time to for the production of {sup 5}1 Cr has been determined as the position of the maximum in the experimental curve P=f(t), where the time-dependent index P used is defined as the product of the number. (Author) 13 refs.

Substrate inhibition: Oxidation of D-sorbitol and D-mannitol by potassium periodate in alkaline medium

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Lakshman Kumar, Y.; Venkata Nadh, R.; Radhakrishnamurti, P. S.

2014-05-01

In the oxidation of D-sorbitol and D-mannitol by potassium periodate in alkaline media, substrate inhibition was observed with both substrates, i.e., a decrease in the rate of the reaction was observed with an increase in the concentration of substrate. The substrate inhibition was attributed to the formation of stable complex between the substrate and periodate. The reactions were found to be first order in case of periodate and a positive fractional order with hydroxide ions. Arrhenius parameters were calculated for the oxidation of sorbitol and mannitol by potassium periodate in alkali media.

Nickel hydroxide electrode. 3: Thermogravimetric investigations of nickel (II) hydroxides

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Dennstedt, W.; Loeser, W.

1982-01-01

Water contained in Ni hydroxide influences its electrochemical reactivity. The water content of alpha and beta Ni hydroxides is different with respect to the amount and bond strength. Thermogravimetric experiments show that the water of the beta Ni hydroxides exceeding the stoichiometric composition is completely removed at 160 deg. The water contained in the interlayers of the beta hydroxide, however, is removed only at higher temperatures, together with the water originating from the decomposition of the hydroxide. These differences are attributed to the formation of II bonds within the interlayers and between interlayers and adjacent main layers. An attempt is made to explain the relations between water content and the oxidizability of the Ni hydroxides.

Magnesium hydroxide as the neutralizing agent for radioactive hydrochloric acid solutions

International Nuclear Information System (INIS)

Palmer, M.J.; Fife, K.W.

1995-10-01

The current technology at Los Alamos for removing actinides from acidic chloride waste streams is precipitation with approximately 10 M potassium hydroxide. Although successful, there are many inherent drawbacks to this precipitation technique which will be detailed in this paper. Magnesium hydroxide (K sp = 1.3 x 10 -11 ) has limited solubility in water and as a result of the common ion effect, cannot generate a filtrate with a pH greater than 9. At a pH of 9, calcium (K sp = 5.5 x 10 -6 ) will not coprecipitate as the hydroxide. This is an important factor since many acidic chloride feeds to hydroxide precipitation contain significant amounts of calcium. In addition, neutralization with Mg(OH) 2 produces a more filterable precipitate because neutralization occurs as the Mg(OH) 2 is dissolved by the acid rather than as a result of the much faster liquid/liquid reaction of KOH with the waste acid. This slower solid/liquid reaction allows time for crystal growth to occur and produces more easily filterable precipitates. On the other hand, neutralization of spent acid with strong KOH that yields numerous hydroxide ions in solution almost instantaneously forming a much larger volume of small crystallites that result in gelatinous, slow-filtering precipitates. Magnesium hydroxide also offers a safety advantage. Although mildly irritating, it is a weak base and safe and easy to handle. From a waste minimization perspective, Mg(OH) 2 offers many advantages. First, the magnesium hydroxide is added as a solid. This step eliminates the diluent water used in KOH neutralizations. Secondly, because the particle size of the precipitate is larger, more actinides are caught on the filter paper resulting in a smaller amount of actinide being transferred to the TA-50 Liquid Waste Treatment Facility. Third, the amount of solids that must be reprocessed is significantly smaller resulting in less waste generation from the downstream processes

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.)

Growth of PbTe nanorods controlled by polymerized tellurium anions and metal(II) amides via composite-hydroxide-mediated approach

International Nuclear Information System (INIS)

Wan Buyong; Hu Chenguo; Liu Hong; Xiong Yufeng; Li Feiyun; Xi Yi; He Xiaoshan

2009-01-01

The pure face-centered-cubic PbTe nanorods have been synthesized by the composite-hydroxide-mediated approach using hydrazine as a reducing agent. The method is based on reaction among reactants in the melts of potassium hydroxide and sodium hydroxide eutectic at 170-220 deg. C and normal atmosphere without using any organic dispersant or surface-capping agent. Scanning electron microscopy, X-ray diffraction, transmission electron microscopy, and energy dispersive X-ray spectroscopy were used to characterize the structure, morphology and composition of the samples. The diameters of nanorods are almost fixed, while the lengths can be tunable under different growth time and temperatures. The growth mechanism of PbTe nanorods is investigated via UV-vis absorption, demonstrating that polymerized tellurium anions and metal(II) amides in the hydrazine hydroxide melts could control the crystallization and growth process of PbTe nanostructures. The band gap of as-synthesized PbTe nanorods has been calculated based on UV-vis-NIR optical diffuse reflectance spectra data.

Growth of PbTe nanorods controlled by polymerized tellurium anions and metal(II) amides via composite-hydroxide-mediated approach

Energy Technology Data Exchange (ETDEWEB)

Wan Buyong [Department of Applied Physics, Chongqing University, 174 Shapingba Street, Chongqing 400044 (China); College of Physics and Information Technology, Chongqing Normal University, Chongqing 400047 (China); Hu Chenguo, E-mail: hucg@cqu.edu.cn [Department of Applied Physics, Chongqing University, 174 Shapingba Street, Chongqing 400044 (China); Liu Hong [State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100 (China); Xiong Yufeng [National Center for Nanoscience and Technology, Beijing 100080 (China); Li Feiyun; Xi Yi; He Xiaoshan [Department of Applied Physics, Chongqing University, 174 Shapingba Street, Chongqing 400044 (China)

2009-09-15

The pure face-centered-cubic PbTe nanorods have been synthesized by the composite-hydroxide-mediated approach using hydrazine as a reducing agent. The method is based on reaction among reactants in the melts of potassium hydroxide and sodium hydroxide eutectic at 170-220 deg. C and normal atmosphere without using any organic dispersant or surface-capping agent. Scanning electron microscopy, X-ray diffraction, transmission electron microscopy, and energy dispersive X-ray spectroscopy were used to characterize the structure, morphology and composition of the samples. The diameters of nanorods are almost fixed, while the lengths can be tunable under different growth time and temperatures. The growth mechanism of PbTe nanorods is investigated via UV-vis absorption, demonstrating that polymerized tellurium anions and metal(II) amides in the hydrazine hydroxide melts could control the crystallization and growth process of PbTe nanostructures. The band gap of as-synthesized PbTe nanorods has been calculated based on UV-vis-NIR optical diffuse reflectance spectra data.

Effect of potassium hydroxide activation in the desulfurization process of activated carbon prepared by sewage sludge and corn straw.

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Zeng, Fan; Liao, Xiaofeng; Hu, Hui; Liao, Li

2018-03-01

Series sludge straw-based activated carbons were prepared by sewage sludge and corn straw with potassium hydroxide (KOH) activation, and the desulfurization performance of activated carbons was studied. To obtain the best desulfurization performance, the optimum ratio between the raw materials and the activator was investigated. The results showed that when the mass ratio of sewage sludge, corn straw, and KOH was 3:7:2, the activated carbon obtained the best breakthrough and saturation sulfur sorption capacities, which were 12.38 and 5.74 times, respectively, those of samples prepared by the nonactivated raw materials. The appropriate KOH could improve the microporosity and alkaline groups, meanwhile reducing the lactone groups, which were all beneficial to desulfurization performance. The chemical adsorption process of desulfurization can be simplified to four main steps, and the main desulfurization products are elemental sulfur and sulfate. Sewage sludge (SS) and corn straw (CS) both have great production and wide distribution and are readily available in China. Much attention has been paid on how to deal with them effectively. Based on the environment protection idea of waste treatment with waste and resource recycling, low-cost adsorbents were prepared by these processes. The proposed method can be expanded to the municipal solid waste recycling programs and renewable energy plan. Thus, proceeding with the study of preparing activated carbon by SS and straw as a carbon-based dry desulfurization agent could obtain huge social, economic, and environmental benefits.

Efficient uranium capture by polysulfide/layered double hydroxide composites.

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Ma, Shulan; Huang, Lu; Ma, Lijiao; Shim, Yurina; Islam, Saiful M; Wang, Pengli; Zhao, Li-Dong; Wang, Shichao; Sun, Genban; Yang, Xiaojing; Kanatzidis, Mercouri G

2015-03-18

There is a need to develop highly selective and efficient materials for capturing uranium (normally as UO2(2+)) from nuclear waste and from seawater. We demonstrate the promising adsorption performance of S(x)-LDH composites (LDH is Mg/Al layered double hydroxide, [S(x)](2-) is polysulfide with x = 2, 4) for uranyl ions from a variety of aqueous solutions including seawater. We report high removal capacities (q(m) = 330 mg/g), large K(d)(U) values (10(4)-10(6) mL/g at 1-300 ppm U concentration), and high % removals (>95% at 1-100 ppm, or ∼80% for ppb level seawater) for UO2(2+) species. The S(x)-LDHs are exceptionally efficient for selectively and rapidly capturing UO2(2+) both at high (ppm) and trace (ppb) quantities from the U-containing water including seawater. The maximum adsorption coeffcient value K(d)(U) of 3.4 × 10(6) mL/g (using a V/m ratio of 1000 mL/g) observed is among the highest reported for U adsorbents. In the presence of very high concentrations of competitive ions such as Ca(2+)/Na(+), S(x)-LDH exhibits superior selectivity for UO2(2+), over previously reported sorbents. Under low U concentrations, (S4)(2-) coordinates to UO2(2+) forming anionic complexes retaining in the LDH gallery. At high U concentrations, (S4)(2-) binds to UO2(2+) to generate neutral UO2S4 salts outside the gallery, with NO3(-) entering the interlayer to form NO3-LDH. In the presence of high Cl(-) concentration, Cl(-) preferentially replaces [S4](2-) and intercalates into LDH. Detailed comparison of U removal efficiency of S(x)-LDH with various known sorbents is reported. The excellent uranium adsorption ability along with the environmentally safe, low-cost constituents points to the high potential of S(x)-LDH materials for selective uranium capture.

Physical and Chemical Interactions between Mg:Al Layered Double Hydroxide and Hexacyanoferrate

Science.gov (United States)

Boclair, Joseph W.; Braterman, Paul S.; Brister, Brian D.; Wang, Zhiming; Yarberry, Faith

2001-11-01

The physical and chemical interactions of ferrocyanide (potassium and ammonium salts) and ferricyanide (potassium salt) with Mg:Al layered double hydroxides (LDH) (having Mg:Al ratios of 2 and 3) are investigated using powder XRD and FTIR spectroscopy. Physically, the potassium ferricyanide is shown to intercalate with a small local field deformation similar to that seen for hexacyanocobaltate (III) in similar materials. Chemically, the reduction of ferricyanide to ferrocyanide upon intercalation is confirmed. Physical interactions of ferrocyanide with 3:1 LDH are shown spectroscopically to include the possible generation of anions in differing environments. Chemically, ferrocyanide is shown to generate cubic ferrocyanides (of the type M2MgFe(CN)6, where M=K+ or NH+4) under conditions where free Mg2+ is likely present in solution, namely, solutions with a pH lower than ∼7.5. It is shown that the reported 2112-cm-1 band found in some chemically altered LDH ferrocyanide is indeed due to interlayer ferricyanide, but that the 2080 cm-1 band is due to the cubic material.

An open, comparative study of 10% potassium hydroxide solution versus salicylic and lactic acid combination in the treatment of molluscum contagiosum in children.

Science.gov (United States)

Köse, Osman; Özmen, İbrahim; Arca, Ercan

2013-08-01

To evaluate and compare the safety and efficacy of 10% potassium hydroxide (KOH) solution and salicylic and lactic acid (SAL + LAC) combination in the treatment of molluscum contagiosum (MC). 26 patients with MC randomized into two treatment groups. 12 patients treated with 10% KOH solution and 14 patients treated with SAL + LAC combination for 6 weeks. Parents of patients were instructed to apply medication once daily only to lesions at study onset. Assessment of response of the treated lesions and side effects was performed at 2, 4 and 6 weeks of the treatment. Newly acquired lesions were not included in the study. At the end of therapy, 83.3% (n = 10) of KOH group demonstrated complete remission and 16.7% (n = 2) of them showed partial remission; four patients (33%) developed new lesions during the study. All the patients in the SAL + LAC combination group (100%) demonstrated complete remission of study entry lesions at the end of 6 weeks with five patients (35%) acquiring new lesions during the study. Minor side effects were observed in two groups. 10% KOH solution and SAL + LAC combination were found to be equally effective in the treatment of MC in children.

A method for the determination of free nitric acid in aqueous plutonium nitrate solutions - potassium fluoride method

International Nuclear Information System (INIS)

Mair, M.A.

1988-06-01

Plutonium IV and VI, and certain other hydrolysable metals which may be present, are converted to non-interfering species by the addition of the sample to potassium fluoride solution. The free acid is then titrated with standard sodium hydroxide solution using phenolphthalein as an indicator. (author)

Development Of Silica Potassium Fertilizers From Trass Rock With Calcination Process

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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.

Evaluating potassium-use-efficiency of five cotton genotypes of pakistan

International Nuclear Information System (INIS)

Hassan, Z.U.; Kubar, K.A.

2014-01-01

Potassium (K) deficiency in Pakistani soils has been recently reported as the major limiting factor affecting sustainable cotton production. The present study was conducted to envisage how K nutrition affect the growth, biomass production, yield and K-use-efficiency of five cotton genotypes, NIBGE-3701, NIBGE-1524 (Bt-transgenic), Sadori, Sindh-1 and SAU-2 (non-Bt conventional), commonly grown in Pakistan. All five genotypes were raised at deficient and adequate K levels, i.e. 0 and 60 kg K/sub 2/O ha-1, respectively. The experiment was performed in plastic pots following a completely randomized factorial design with three repeats. Adequate K nutrition significantly increased various plant growth traits and yield of all cotton genotypes under study, viz. number of sympodia (21%), number of leaves (34%), leaf dry biomass (30%), shoot dry biomass (31%), number of bolls (50%) and yield of seed cotton (92%). Substantial variations were observed among cotton genotypes for their K-use-efficiency and K-response-efficiency. Sadori and SAU-2 were screened as most K-use-efficient cotton genotypes, while Sindh-1 and SAU-2 were ranked as the most K-responsive cotton genotypes. Interestingly, Sadori did not respond to K nutrition. Moreover, Bt cotton genotypes accumulated more K as compared to non-Bt genotypes. The cotton genotype SAU-2 was identified as efficient-response genotype for better adaptation for both low- and high-K-input sustainable cotton agriculture systems. (author)

Continuous Process for Biodiesel Production in Packed Bed Reactor from Waste Frying Oil Using Potassium Hydroxide Supported on Jatropha curcas Fruit Shell as Solid Catalyst

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Achanai Buasri

2012-08-01

Full Text Available The transesterification of waste frying oil (WFO with methanol in the presence of potassium hydroxide catalyst supported on Jatropha curcas fruit shell activated carbon (KOH/JS was studied. The catalyst systems were characterized by X-ray diffraction (XRD, scanning electron microscopy (SEM and the Brunauer–Emmett–Teller (BET method. The effects of reaction variables such as residence time, reaction temperature, methanol/oil molar ratio and catalyst bed height in packed bed reactor (PBR on the yield of biodiesel were investigated. SEM images showed that KOH was well distributed on the catalyst support. The optimum conditions for achieving the conversion yield of 86.7% consisted of a residence time of 2 h, reaction temperature of 60 °C, methanol/oil molar ratio of 16 and catalyst bed height of 250 mm. KOH/JS could be used repeatedly five times without any activation treatment, and no significant activity loss was observed. The results confirmed that KOH/JS catalyst had a great potential to be used for industrial application in the transesterification of WFO. The fuel properties of biodiesel were also determined.

Electrochromic nickel oxide films and their compatibility with potassium hydroxide and lithium perchlorate in propylene carbonate: Optical, electrochemical and stress-related properties

International Nuclear Information System (INIS)

Wen, Rui-Tao; Niklasson, Gunnar A.; Granqvist, Claes G.

2014-01-01

Porous nickel oxide films were deposited onto unheated indium tin oxide coated glass substrates by reactive dc magnetron sputtering. These films had a cubic NiO structure. Electrochromic properties were evaluated in 1 M potassium hydroxide (KOH) and in 1 M lithium perchlorate in propylene carbonate (Li–PC). Large optical modulation was obtained for ∼ 500-nm-thick films both in KOH and in Li–PC (∼ 70% and ∼ 50% at 550 nm, respectively). In KOH, tensile and compressive stresses, due to the expansion and contraction of the lattice, were found for films in their bleached and colored state, respectively. In Li–PC, compressive stress was seen both in colored and bleached films. Durability tests with voltage sweeps between − 0.5 and 0.65 V vs Ag/AgCl in KOH showed good durability for 10,000 cycles, whereas voltage sweeps between 2.0 and 4.7 V vs Li/Li + in Li–PC yielded significant degradation after 1000 cycles. - Highlights: • Ni oxide films were studied in KOH and in LiClO 4 + propylene carbonate (Li–PC). • Good electrochromism was found in both electrolytes. • In KOH, tensile/compressive stresses were seen in bleached/colored films. • In Li–PC, compressive stress was seen both in colored and bleached films

Photocatalytic organic transformation by layered double hydroxides: highly efficient and selective oxidation of primary aromatic amines to their imines under ambient aerobic conditions.

Science.gov (United States)

Yang, Xiu-Jie; Chen, Bin; Li, Xu-Bing; Zheng, Li-Qiang; Wu, Li-Zhu; Tung, Chen-Ho

2014-06-25

We report the first application of layered double hydroxide as a photocatalyst in the transformation of primary aromatic amines to their corresponding imines with high efficiency and selectivity by using oxygen in an air atmosphere as a terminal oxidant under light irradiation.

Production of the Lax Ca1-x Cry Al1-y O3 compound through hydroxide precipitation

International Nuclear Information System (INIS)

Martins, L.C.; Machado, A.J.S.

1996-01-01

Purposing to reduce the cost of preparation of the lanthanum chromite doped with calcium and aluminum, it was made a study of the condition of hydroxide precipitation, using calcium, chromium and aluminum nitrates and lanthanum oxide, as precursors and as precipitate agent was used potassium hydroxide. In this study are showed results about the reaction kinetic, x-ray diffraction and yield as function of the pH. These results suggest a high yield for also elements studied. The phase of stoichiometry, La 0.8 Ca 0.2 Cr 0.75 Al 0.25 O 3 was obtained in low temperature. In fact, this process is viable to produce of lanthanum chromite doped with calcium and aluminum. (author)

Efficient carbon dots/NiFe-layered double hydroxide/BiVO4 photoanodes for photoelectrochemical water splitting

Science.gov (United States)

Lv, Xiaowei; Xiao, Xin; Cao, Minglei; Bu, Yi; Wang, Chuanqing; Wang, Mingkui; Shen, Yan

2018-05-01

Modification of semiconductor photoanodes with oxygen evolution catalyst (OEC) is an effective approach for improving photoelectrochemical (PEC) water splitting efficiency. In the configuration, how to increase the activity of OEC is crucial to further improve PEC performance. Herein, a ternary photoanode system was designed to enhance PEC efficiency of photoelectrodes through introducing carbon dots (CDs), NiFe-layered double hydroxide (NiFe-LDH) nanosheets on BiVO4 particles. Systematic research shows that NiFe-LDH serves as an OEC which accelerates oxygen evolution kinetics, while the introduction of CDs can further reduce charge transfer resistance and overpotential for oxygen evolution. Under the synergistic effect of NiFe-LDH and CDs, the photocurrent and incident photon to current conversion efficiency (IPCE) of the resulting CDs/NiFe-LDH/BiVO4 photoanode is improved significantly than those of the NiFe-LDH/BiVO4 electrode. Consequently, such a ternary heterostructure could be an alternative way to further enhance PEC water splitting performance.

The sensitivity and specificity of potassium hydroxide smear and fungal culture relative to clinical assessment in the evaluation of tinea pedis: a pooled analysis.

Science.gov (United States)

Levitt, Jacob Oren; Levitt, Barrie H; Akhavan, Arash; Yanofsky, Howard

2010-01-01

Background. There are relatively few studies published examining the sensitivity and specificity of potassium hydroxide (KOH) smear and fungal culture examination of tinea pedis. Objective. To evaluate the sensitivity and specificity of KOH smear and fungal culture for diagnosing tinea pedis. Methods. A pooled analysis of data from five similarly conducted bioequivalence trials for antifungal drugs was performed. Data from 460 patients enrolled in the vehicle arms of these studies with clinical diagnosis of tinea pedis supported by positive fungal culture were analyzed 6 weeks after initiation of the study to determine the sensitivity and specificity of KOH smear and fungal culture. Results. Using clinical assessment as the gold standard, the sensitivities for KOH smear and culture were 73.3% (95% CI: 66.3 to 79.5%) and 41.7% (34.6 to 49.1%), respectively. The respective specificities for culture and KOH smear were 77.7% (72.2 to 82.5%) and 42.5% (36.6 to 48.6%). Conclusion. KOH smear and fungal culture are complementary diagnostic tests for tinea pedis, with the former being the more sensitive test of the two, and the latter being more specific.

The Sensitivity and Specificity of Potassium Hydroxide Smear and Fungal Culture Relative to Clinical Assessment in the Evaluation of Tinea Pedis: A Pooled Analysis

Directory of Open Access Journals (Sweden)

Jacob Oren Levitt

2010-01-01

Full Text Available Background. There are relatively few studies published examining the sensitivity and specificity of potassium hydroxide (KOH smear and fungal culture examination of tinea pedis. Objective. To evaluate the sensitivity and specificity of KOH smear and fungal culture for diagnosing tinea pedis. Methods. A pooled analysis of data from five similarly conducted bioequivalence trials for antifungal drugs was performed. Data from 460 patients enrolled in the vehicle arms of these studies with clinical diagnosis of tinea pedis supported by positive fungal culture were analyzed 6 weeks after initiation of the study to determine the sensitivity and specificity of KOH smear and fungal culture. Results. Using clinical assessment as the gold standard, the sensitivities for KOH smear and culture were 73.3% (95% CI: 66.3 to 79.5% and 41.7% (34.6 to 49.1%, respectively. The respective specificities for culture and KOH smear were 77.7% (72.2 to 82.5% and 42.5% (36.6 to 48.6%. Conclusion. KOH smear and fungal culture are complementary diagnostic tests for tinea pedis, with the former being the more sensitive test of the two, and the latter being more specific.

Magnesium Hydroxide

Science.gov (United States)

Magnesium hydroxide is used on a short-term basis to treat constipation.This medication is sometimes prescribed ... Magnesium hydroxide come as a tablet and liquid to take by mouth. It usually is taken as ...

Aluminum Hydroxide

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Aluminum hydroxide is used for the relief of heartburn, sour stomach, and peptic ulcer pain and to ... Aluminum hydroxide comes as a capsule, a tablet, and an oral liquid and suspension. The dose and ...

An open, randomized, comparative clinical and histological study of imiquimod 5% cream versus 10% potassium hydroxide solution in the treatment of molluscum contagiosum.

Science.gov (United States)

Seo, Sang-Hee; Chin, Hyun-Woo; Jeong, Dong-Wook; Sung, Hyun-Woo

2010-05-01

Although molluscum contagiosum (MC) resolves spontaneously, there are several reasons to treat this dermatological disorder. To evaluate the safety and efficacy of 5% imiquimod cream versus 10% potassium hydroxide (KOH) solution in treating MC, and to propose the mechanism of cure by observing the histological findings. Imiquimod or KOH were applied by the patient or a parent 3 days per week until all lesions cleared. The number of MC lesions was counted and side effects were evaluated at 5 points during the treatment (the initial visit, week 2, week 4, week 8, and week 12). Histological changes were compared between 2 patients of each group, before and after the 2 weeks of application. In both group, the mean lesion counts decreased all through to week 12, and the reduction in number of lesions were statistically significant in both groups (p <0.005). Over 40% of each group developed local side effects, and no systemic side effects were noted in either group. Before treatment, histological findings showed little or no dermal infiltrates. After treatment, specimens showed dense lymphocytic infiltrates, especially T cells, around the lesions which had resolved. Both 10% KOH solution and 5% imiquimod cream are effective and safe treatment of MC.

Facile preparation of layered double hydroxide/MoS{sub 2}/poly(vinyl alcohol) composites

Energy Technology Data Exchange (ETDEWEB)

Zhou, Keqing, E-mail: zhoukq@cug.edu.cn [Faculty of Engineering, China University of Geosciences (Wuhan), 388 Lumo Road, Wuhan, Hubei, 430074 (China); Hu, Yixin [Department of Chemistry, Lanzhou University, Lanzhou 730000 (China); Liu, Jiajia [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026 (China); Gui, Zhou, E-mail: zgui@ustc.edu.cn [State Key Laboratory of Fire Science, University of Science and Technology of China, 96 Jinzhai Road, Hefei, Anhui, 230026 (China); Jiang, Saihua [School of Mechanical and Automotive Engineering, South China University of Technology, Wushan Road 381, Guangzhou, 510641 (China); Tang, Gang [School of Architecture and Civil Engineering, Anhui University of Technology, 59 Hudong Road, Ma' anshan, Anhui, 243002 (China)

2016-08-01

In present study, the layered double hydroxide/MoS{sub 2} hybrids are facilely synthesized by self-assembly of exfoliated MoS{sub 2} nanosheets and layered double hydroxide nanoplates via electrostatic interaction, with the aim of combining their physical and chemical functionalities to form a promising nanofiller for flame retardancy in polymer composites. The structure and morphology of the layered double hydroxide/MoS{sub 2} hybrids are probed by X-ray diffraction and transmission electron microscopy. Subsequently, the hybrids are incorporated into poly (vinyl alcohol) to serve as reinforcements. The flame retardant efficiency of MoS{sub 2} nanosheets in poly (vinyl alcohol) is significantly enhanced after the incorporation of layered double hydroxide nanoplates, which can be explained by the forming of a compact and uniform char during combustion. - Highlights: • The LDH/MoS{sub 2} hybrids were facilely synthesized by self-assembly method. • The flame retardant efficiency of LDH/MoS{sub 2} hybrids in PVA was significantly enhanced. • It is a promising strategy for improving the flame retardant efficiency of MoS{sub 2}.

Selective extraction by dissolvable (nitriloacetic acid-nickel)-layered double hydroxide coupled with reaction with potassium thiocyanate for sensitive detection of iron(III).

Science.gov (United States)

Tang, Sheng; Chang, Yuepeng; Shen, Wei; Lee, Hian Kee

2016-07-01

A highly selective method has been proposed for the determination of iron cation (Fe(3+)). (Nitriloacetic acid-nickel)-layered double hydroxide ((NTA-Ni)-LDH) was successfully synthesized and used as dissolvable sorbent in dispersive solid-phase extraction to pre-concentrate and separate Fe(3+) from aqueous phase. Since Fe(3+) has a larger formation constant with NTA compared to Ni(2+), subsequently ion exchange occurred when (NTA-Ni)-LDH was added to the sample solution. The resultant (NTA-Fe)-LDH sol was isolated and transferred in an acidic medium containing potassium thiocyanate (KSCN). Since (NTA-Fe)-LDH could be dissolved in acidic conditions, Fe(3+)was released and reacted with SCN(-) to form an Fe-SCN complex. The resulting product was measured by ultraviolet-visible spectrometry for quantitative detection of Fe(3+). Extraction factors, including sample pH, reaction pH, extraction temperature, extraction time, reaction time and concentration of KSCN were optimized. This method achieved a low limit of detection of 15.2nM and a good linear range from 0.05 to 50μM (r(2)=0.9937). A nearly 18-fold enhancement of signal intensity was achieved after selective extraction. The optimized conditions were validated by applying the method to determine Fe(3+) in seawater samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Electrochromic nickel oxide films and their compatibility with potassium hydroxide and lithium perchlorate in propylene carbonate: Optical, electrochemical and stress-related properties

Energy Technology Data Exchange (ETDEWEB)

Wen, Rui-Tao, E-mail: Ruitao.Wen@angstrom.uu.se; Niklasson, Gunnar A.; Granqvist, Claes G.

2014-08-28

Porous nickel oxide films were deposited onto unheated indium tin oxide coated glass substrates by reactive dc magnetron sputtering. These films had a cubic NiO structure. Electrochromic properties were evaluated in 1 M potassium hydroxide (KOH) and in 1 M lithium perchlorate in propylene carbonate (Li–PC). Large optical modulation was obtained for ∼ 500-nm-thick films both in KOH and in Li–PC (∼ 70% and ∼ 50% at 550 nm, respectively). In KOH, tensile and compressive stresses, due to the expansion and contraction of the lattice, were found for films in their bleached and colored state, respectively. In Li–PC, compressive stress was seen both in colored and bleached films. Durability tests with voltage sweeps between − 0.5 and 0.65 V vs Ag/AgCl in KOH showed good durability for 10,000 cycles, whereas voltage sweeps between 2.0 and 4.7 V vs Li/Li{sup +} in Li–PC yielded significant degradation after 1000 cycles. - Highlights: • Ni oxide films were studied in KOH and in LiClO{sub 4} + propylene carbonate (Li–PC). • Good electrochromism was found in both electrolytes. • In KOH, tensile/compressive stresses were seen in bleached/colored films. • In Li–PC, compressive stress was seen both in colored and bleached films.

Silver(I) and copper(II)-imidazolium carboxylates: Efficient catalysts ...

Indian Academy of Sciences (India)

GANESAN PRABUSANKAR

the reaction between corresponding carboxylic acid ligands and metal salts. These new metal .... g), DMF (2 mL) and water (1 mL) was added; then, the sus- pension was ..... ence of five mol% potassium hydroxide as base in 1 and. Scheme 3.

An open, nonrandomized, comparative study of imiquimod 5% cream versus 10% potassium hydroxide solution in the treatment of molluscum contagiosum.

Science.gov (United States)

Metkar, Amol; Pande, Sushil; Khopkar, Uday

2008-01-01

There are numerous therapeutic modalities available for treatment of molluscum contagiosum. However, the ablative modalities are painful and not suitable for children. We aimed to evaluate and compare the safety and efficacy of 2 of the painless modalities, viz., 5% imiquimod cream and 10% potassium hydroxide (KOH) solution, in the treatment of molluscum contagiosum. Out of a total of 40 patients of molluscum contagiosum in the study, 18 patients in the imiquimod group and 19 patients in the KOH group completed the study. The given medication was applied by the patient or a parent to mollusca at night, 3 days per week. Imiquimod was continued till clinical cure; and 10% KOH, till lesions showed signs of inflammation. Assessments of response and side effects were performed at the end of week 4, week 8, and week 12. Significance was tested by Student's t test and Mann-Whitney test. The mean lesion count decreased from 22.39 to 10.75 with imiquimod and from 20.79 to 4.31 with KOH at the end of 12 weeks. We found complete clearance of lesions in 8 (44%) patients with imiquimod and in 8 (42.1%) patients with 10% KOH. Minor side effects were seen in 15 (78.9%) patients on KOH and 10 (55.5%) patients on imiquimod. The results of this study suggest that both 5% imiquimod cream and 10% KOH solution are equally effective in molluscum contagiosum though KOH has a faster onset of action. However, KOH solution is associated with a higher incidence of side effects.

The recovery of tin, and the production of niobium pentoxide and potassium tantalum fluoride, from a tin slag

International Nuclear Information System (INIS)

Iorio, G.; Tyler, M.S.

1987-01-01

This report describes the results of testwork on the recovery of tin, niobium, and tantalum from a tin slag. The slag, which consisted mainly of amorphous silica, with varying amounts of calcuim, magnesium, manganese, iron, and aluminium, contained an average of 8,8 per cent niobium pentoxide and 6,2 per cent tantalum pentoxide. The metallic tin-ion phase was removed from the crushed slag by magnetic separation. The slag was then leached with hydrochloric acid to remove magnesium, calcium, aluminium, iron, manganese, and the remainder of the tin. Leaching with sodium hydroxide for the removal of silica and phosphorous was followed by a final leach with hydrochloric acid for the removal of sodium. The upgraded concentrate thus obtained was purified by leaching with hydrofluoric acid, solvent extraction of niobium and tantalum into tri-n-butyl phosphate and methyl isobutyl ketone, and selective stripping of niobium with sulphuric acid and tantalum with ammonium floride. Niobium pentoxide and potassium tantalum fluoride were then precipitated by the addition of ammonium hydroxide and potassium fluoride to the respective strip liquors. The overall recoveries in the upgraded concentrate were 98 per cent for tantalum and 92 per cent for niobium. Dissolutions and recoveries of over 99 per cent were obtained for both tantalum and niobium in the purification steps. The niobium pentoxide and potassium tantalum fluoride precipitates obtained were of high purity

The sampling of hydrogen sulfide in air with impregnated filter paper

NARCIS (Netherlands)

Huygen, C.

1964-01-01

A method is proposed for the quantitative collection of hydrogen sulfide in air on impregnated filter paper. An aqueous solution of potassium hydroxide, potassium zincate and glycerol is used as impregnating fluid. The stability of the collected sulfide and the efficiency of collection at different

Potassium efficiency of wheat and sugar beet evaluated under field conditions

International Nuclear Information System (INIS)

El Dessougi, H. I.; Claassen, N.; Steingrobe, B.

2011-01-01

This study was conducted to investigate the potassium (K) efficiency of wheat and sugar beet under field conditions and to identify the varying mechanisms or factors behind their efficiency. Data were obtained from a long term fertilizer experiment, on a K (fixing) sandy clay loam in Bavaria, southern Germany, in which K fertilization rates varied from 0 to 1000 kg K ha - 1 year - 1 with the last K application in 1986. In 2003, sugar beet and spring wheat were sown on March 13 t h and April 4 t h respectively. At 4 and 5 harvests for wheat and sugar beet, respectively, random samples of shoots, roots and soil of each species from the unfertilized (-K) and the highest fertilizer level of 1000 kg K ha - 1 (+K) treatments were analyzed. Sugar beet and wheat had similar K efficiency producing 76% and 80% beet and grain yield on unfertilized compared with fertilized treatments, respectively. As compared to wheat, sugar beet had a higher internal K requirement, two times higher shoots growth rate (GRs), 34% to 48% of the wheat root length (RL), and consequently a larger GR/RL, that is higher demand for K uptake on the roots. However, sugar beet showed an exceptionally high uptake efficiency of the single roots or influx, which was 5 times higher in unfertilized treatments, as compared with wheat. Wheat K efficiency was attributed to a higher utilization efficiency or lower internal requirement, slow growing shoots and a large root system. Further investigations are necessary to study the mechanism by which sugar beet was able to achieve a higher influx than wheat.(Author)

A regenerable potassium and phosphate sorbent system to enhance dialysis efficacy and device portability: an in vitro study.

Science.gov (United States)

Wester, Maarten; Simonis, Frank; Gerritsen, Karin G; Boer, Walther H; Wodzig, Will K; Kooman, Jeroen P; Joles, Jaap A

2013-09-01

Continuous dialysis could provide benefit by constant removal of potassium and phosphate. This study investigates the suitability of specific potassium and phosphate sorbents for incorporation in an extracorporeal device by capacity and regenerability testing. Capacity testing was performed in uraemic plasma. Regenerability was tested for potassium sorbents, with adsorption based on cationic exchange for sodium, with 0.1 M and 1.0 M NaCl. To regenerate phosphate sorbents, with adsorption based on anionic exchange, 0.1 M and 1.0 M NaHCO3 and NaOH were used. Subsequently, sodium polystyrene divinylbenzene sulphonate (RES-A) and iron oxide hydroxide (FeOOH) beads were incorporated in a cartridge for testing in bovine blood using a recirculating blood circuit and a dialysis circuit separated by a high-flux dialyzer (dynamic setup). Preloading was tested to assess whether this could limit calcium and magnesium adsorption. In the batch-binding assays, zirconium phosphate most potently adsorbed potassium (0.44 ± 0.05 mmol/g) and RES-A was the best regenerable potassium sorbent (92.9 ± 5.7% with 0.1 M NaCl). Zirconium oxide hydroxide (ZIR-hydr) most potently adsorbed phosphate (0.23 ± 0.05 mmol/g) and the polymeric amine sevelamer carbonate was the best regenerable sorbent (85.7 ± 5.2% with 0.1 M NaHCO3). In the dynamic setup, a potassium adsorption of 10.72 ± 2.06 mmol in 3 h was achieved using 111 g of RES-A and a phosphate adsorption of 4.73 ± 0.53 mmol in 3 h using 55 g of FeOOH. Calcium and magnesium preloading was shown to reduce the net adsorption in 3 h from 3.57 ± 0.91 to -0.29 ± 1.85 and 1.02 ± 0.05 to -0.31 ± 0.18 mmol, respectively. RES-A and FeOOH are suitable, regenerizable sorbents for potassium and phosphate removal in dialysate regeneration. Use of zirconium carbonate and ZIR-hydr may further increase phosphate adsorption, but may compromise sorbent regenerability. Use of polymeric amines for phosphate adsorption may enhance sorbent

Calcium hydroxide poisoning

Science.gov (United States)

Hydrate - calcium; Lime milk; Slaked lime ... Calcium hydroxide ... These products contain calcium hydroxide: Cement Limewater Many industrial solvents and cleaners (hundreds to thousands of construction products, flooring strippers, brick cleaners, cement ...

Sodium hydroxide poisoning

Science.gov (United States)

Sodium hydroxide is a very strong chemical. It is also known as lye and caustic soda. This ... poisoning from touching, breathing in (inhaling), or swallowing sodium hydroxide. This article is for information only. Do ...

Behaviour of 29Si NMR and infrared spectra of aqueous sodium and potassium silica solutions as a function of (SiO2/M2+O) ratio

International Nuclear Information System (INIS)

Couty, R.; Fernandez, L.

1996-01-01

Sodium and potassium solutions of silica with silica concentration of 1,4 mo/kg and R ms = SiO 2 /M + 2 O ratios of 4.56 to 1.6 were obtained by depolymerization of amorphous silica gel in sodium and potassium hydroxide. Solutions have been characterized by 29 Si NMR and infrared spectroscopy. The results indicated that Na + and K + exhibit the same behaviour during the depolymerization of silica. (authors). 11 refs., 4 figs., 2 tabs

Fabrication of Elemental Copper by Intense Pulsed Light Processing of a Copper Nitrate Hydroxide Ink.

Science.gov (United States)

Draper, Gabriel L; Dharmadasa, Ruvini; Staats, Meghan E; Lavery, Brandon W; Druffel, Thad

2015-08-05

Printed electronics and renewable energy technologies have shown a growing demand for scalable copper and copper precursor inks. An alternative copper precursor ink of copper nitrate hydroxide, Cu2(OH)3NO3, was aqueously synthesized under ambient conditions with copper nitrate and potassium hydroxide reagents. Films were deposited by screen-printing and subsequently processed with intense pulsed light. The Cu2(OH)3NO3 quickly transformed in less than 100 s using 40 (2 ms, 12.8 J cm(-2)) pulses into CuO. At higher energy densities, the sintering improved the bulk film quality. The direct formation of Cu from the Cu2(OH)3NO3 requires a reducing agent; therefore, fructose and glucose were added to the inks. Rather than oxidizing, the thermal decomposition of the sugars led to a reducing environment and direct conversion of the films into elemental copper. The chemical and physical transformations were studied with XRD, SEM, FTIR and UV-vis.

Bacterial flora of processed broiler chicken skin after successive washings in mixtures of potassium hydroxide and lauric acid.

Science.gov (United States)

Hinton, Arthur; Cason, John A

2008-08-01

Changes in the size of populations of different groups of bacteria composing the normal flora of processed broiler skin were examined after each of five consecutive washings in mixtures of potassium hydroxide (KOH) and lauric acid (LA). Portions of skin from commercially processed broiler carcasses were washed in distilled water (control) or in mixtures of 0.25% KOH-0.5% LA or 0.5% KOH-1% LA by using a stomacher laboratory blender to agitate the skin in the solutions. After each wash, skin was transferred to fresh solutions, and washing was repeated to provide samples washed one to five times in each solution. Bacteria in rinsates of the washed skin were enumerated on plate count (PC) agar, Staphylococcus (STA) agar, Levine eosin methylene blue (EMB) agar, lactic acid bacteria (LAB) agar, and Perfringens (PER) agar with TSC supplement. Selected isolates recovered on each medium were identified. Overall, no significant differences were observed in numbers of bacteria recovered on PC, STA, or EMB agars from skin after repeated washing in water, but there were significant reductions in the number of bacteria recovered on LAB and PER agars. Repeated washing of skin in 0.25% KOH-0.5% LA or 0.5% KOH-1% LA generally produced significant reductions in the number of bacteria recovered on all media. Furthermore, no bacteria were recovered on PER agar from skin washed five times in 0.25% KOH-0.5% LA. Likewise, no bacteria were recovered on EMB or LAB agars from skin washed three or more times in 0.5% KOH-1% LA or on PER agar from skin washed four or five times in this solution. Staphylococcus spp. were identified as the skin isolates with the highest degree of resistance to the bactericidal activity of KOH-LA. Findings indicate that although bacteria may be continually shed from poultry skin after repeated washings, bactericidal surfactants can be used to remove and kill several types of bacteria found on the surface of the skin of processed broilers.

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.

Potassium efficiency of different crops grown on a sandy soil under controlled conditions

International Nuclear Information System (INIS)

El Dessougi, H. I.; Claassen, N.; Steingrobe, B.

2010-01-01

The objective of this work was to study K efficiency of different crops and determine the plant parameters affecting it. The study was carried out using 14 different crops and cultivars grown on a sandy soil rich in humus, with two potassium fertilisation levels under controlled conditions. The studied crops showed different K efficiency reflected in different dry matter yield production in unfertilised relative to fertilised treatments. All crops had , at low K supply, less than optimum K concentration in dry matter, indicating that the soil K concentration did not meet the K requirement of the plants, Thus, the ability to produce high dry matter yield indicated superior adaptability to K deficiency. The efficiency mechanisms employed by the different crops were low shoot growth rate and/or high root length-shoot weigh ratio and a high uptake rate per unit root, i.e. the influx, or low internal K requirement. Crops with high influx had higher calculated concentration gradients, since they caused further decrease of the concentration at the root surface. As such, they were able to create steeper concentration gradients between bulk soil solution and root surface. This resulted in higher diffusive flux to the roots.(Author)

Host-Guest Engineering of Layered Double Hydroxides towards Efficient Oxygen Evolution Reaction: Recent Advances and Perspectives

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Jianming Li

2018-05-01

Full Text Available Electrochemical water splitting has great potential in the storage of intermittent energy from the sun, wind, or other renewable sources for sustainable clean energy applications. However, the anodic oxygen evolution reaction (OER usually determines the efficiency of practical water electrolysis due to its sluggish four-electron process. Layered double hydroxides (LDHs have attracted increasing attention as one of the ideal and promising electrocatalysts for water oxidation due to their excellent activity, high stability in basic conditions, as well as their earth-abundant compositions. In this review, we discuss the recent progress on LDH-based OER electrocatalysts in terms of active sites, host-guest engineering, and catalytic performances. Moreover, further developments and challenges in developing promising electrocatalysts based on LDHs are discussed from the viewpoint of molecular design and engineering.

Transformation of zinc hydroxide chloride monohydrate to crystalline zinc oxide.

Science.gov (United States)

Moezzi, Amir; Cortie, Michael; McDonagh, Andrew

2016-04-25

Thermal decomposition of layered zinc hydroxide double salts provides an interesting alternative synthesis for particles of zinc oxide. Here, we examine the sequence of changes occurring as zinc hydroxide chloride monohydrate (Zn5(OH)8Cl2·H2O) is converted to crystalline ZnO by thermal decomposition. The specific surface area of the resultant ZnO measured by BET was 1.3 m(2) g(-1). A complicating and important factor in this process is that the thermal decomposition of zinc hydroxide chloride is also accompanied by the formation of volatile zinc-containing species under certain conditions. We show that this volatile compound is anhydrous ZnCl2 and its formation is moisture dependent. Therefore, control of atmospheric moisture is an important consideration that affects the overall efficiency of ZnO production by this process.

Significance of Gram's stain smear, potassium hydroxide mount, culture, and microscopic pathology in the diagnosis of acrodermatitis continua of Hallopeau.

Science.gov (United States)

Sehgal, Virendra N; Sharma, Sonal

2011-01-01

A 21-year-old housewife presented to the authors' clinic in 2009 with recurrent papulovesicular and pustular eruptions on the index an ring fingers of the left hand accompanied by throbbing pain that had been active for the past 10 years. The condition did not respond to topical and/or systemic treatment. There was neither a personal/family history of psoriasis nor any other systemic disease. The sk surface of the patient's left hand was marked by the presence of multiple pustules located over an erythematous background, affecting th ring and adjoining middle fingers, with crusting prominent in places along the tips (Figure 1). Gram-stained smears prepared from th purulent specimen revealed Gram-positive cocci in clusters. Potassium hydroxide (KOH) examination of the pustules did not show a fungal elements. In vitro culture of the same specimen yielded growth of Staphylococcus aureus, which was found to be sensitive to almo all conventional antibiotics on aerobic culture. Sections prepared from the skin of the tip of the patient's finger showed marked epithelial hyperplasia with uniform elongation of rete ridges and supra-papillary thinning of the epidermis. There was hyperkeratosis with foci of mounds of parakeratosis. Spongiosis with neutrophilic infiltration and microabscess formation were prominent. The dermis showed perivascular lymphohistiocytic infiltrate (Figure 2A and 2B). No organism was identified on special stains. Results from hemography and liver and renal function tests were within normal limits. The diagnosis of acrodermatitis continua of Hallopeau (ACH) was made, in keeping with the findings. The patient received ceftriaxone 1.0 g and tazobactam 125 mg by slow intravenous infusion for 3 consecutive days, following which there was complete regression of the lesions. After cessation of therapy, there was complete recurrence.

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.

Short and Efficient Synthesis of Optically Active N-Tosyl Aziridines from 2-Amino Alcohols

Directory of Open Access Journals (Sweden)

Maria C. F. de Araújo

2002-12-01

Full Text Available Two alternative and complementary one-pot procedures for the direct transformation of 2-amino alcohols to N-tosyl aziridines are presented. The unsubstituted parent compound and its less hindered homologues can be obtained in high yields by tosylation and in situ cyclisation effected by potassium hydroxide in water/dichloromethane. Higher substituted amino alcohols give better yields using potassium carbonate in acetonitrile. Both procedures use simple inorganic bases and produce only inorganic salts as byproducts.

Comparison of potassium hydroxide mount and mycological culture with histopathologic examination using periodic acid-Schiff staining of the nail clippings in the diagnosis of onychomycosis.

Science.gov (United States)

Shenoy, M Manjunath; Teerthanath, S; Karnaker, Vimal K; Girisha, B S; Krishna Prasad, M S; Pinto, Jerome

2008-01-01

Onychomycosis is a common problem noticed in clinical practice. Currently available standard laboratory methods show inconsistent sensitivity; hence there is a need for newer methods of detection. This study involves comparison of standard laboratory tests in the diagnosis of onychomycosis, namely, potassium hydroxide mount (KOH mount) and mycological culture, with histopathologic examination using periodic acid-Schiff (PAS) staining of the nail clippings. A total of 101 patients with clinically suspected onychomycosis were selected. Nail scrapings and clippings were subjected to KOH mount for direct microscopic examination, culture using Sabouraud's dextrose agar (with and without antibiotics) and histopathologic examination with PAS staining (HP/PAS). Statistical analysis was done by McNemar's test. Direct microscopy with KOH mount, mycological culture, and HP/PAS showed positive results in 54 (53%), 35 (35%), and 76 (75%) patients respectively. Laboratory evidence of fungal infection was obtained in 84 samples by at least one of these three methods. Using this as the denominator, HP/PAS had a sensitivity of 90%, which was significantly higher compared to that of KOH mount (64%) or mycological culture (42%). Histopathologic diagnosis with PAS staining of nail clippings was the most sensitive among the tests. It was easy to perform, rapid, and gave significantly higher rates of detection of onychomycosis compared to the standard methods, namely KOH mount and mycological culture.

Efficiency of Iron-Based Oxy-Hydroxides in Removing Antimony from Groundwater to Levels below the Drinking Water Regulation Limits

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Konstantinos Simeonidis

2017-02-01

Full Text Available This study evaluates the efficiency of iron-based oxy-hydroxides to remove antimony from groundwater to meet the requirements of drinking water regulations. Results obtained by batch adsorption experiments indicated that the qualified iron oxy-hydroxide (FeOOH, synthesized at pH 4 for maintaining a high positive charge density (2.5 mmol OH−/g achieved a residual concentration of Sb(III below the EU drinking water regulation limit of 5 μg/L by providing an adsorption capacity of 3.1 mg/g. This is more than twice greater compared either to similar commercial FeOOHs (GFH, Bayoxide or to tetravalent manganese feroxyhyte (Fe-MnOOH adsorbents. In contrast, all tested adsorbents failed to achieve a residual concentration below 5 μg/L for Sb(V. The higher efficiency of the qualified FeOOH was confirmed by rapid small-scale column tests, since an adsorption capacity of 3 mg Sb(III/g was determined at a breakthrough concentration of 5 μg/L. However, it completely failed to achieve Sb(V concentrations below 5 μg/L even at the beginning of the column experiments. The results of leaching tests classified the spent qualified FeOOH to inert wastes. Considering the rapid kinetics of this process (i.e., 85% of total removal was performed within 10 min, the developed qualified adsorbent may be promoted as a prospective material for point-of-use Sb(III removal from water in vulnerable communities, since the adsorbent’s cost was estimated to be close to 30 ± 3.4 €/103 m3 for every 10 μg Sb(III/L removed.

Formation of mixed hydroxides in the thorium chloride-iron chloride-sodium hydroxide system

International Nuclear Information System (INIS)

Krivokhatskij, A.S.; Prokudina, A.F.; Sapozhnikova, T.V.

1976-01-01

The process of formation of mixed hydroxides in the system thorium chloride-iron chloride-NaOH was studied at commensurate concentrations of Th and Fe in solution (1:1 and 1:10 mole fractions, respectively) with ionic strength 0.3, 2.1, and 4.1, created with the electrolyte NaCl, at room temperature 22+-1degC. By the methods of chemical, potentiometric, thermographic, and IR-spectrometric analyses, it was shown that all the synthesized precipitates are mechanical mixtures of two phases - thorium hydroxide and iron hydroxide - and not a new hydrated compound. The formal solubility of the precipitates of mixed hydroxides was determined. It was shown that the numerical value of the formal solubility depends on the conditions of formation and age of the precipitates

Study of the Efficiency of Arsenic Removal from Drinking Water by Granular Ferric Hydroxide (GFH

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.R. Asgari

2008-04-01

Full Text Available Background and ObjectivePollution of surface and ground water to arsenic (As has been reported from many parts of the world and in some regions of Iran especially in Kurdistan province. Natural pollution of water to As is in fact dependent to geological characteristics of a region. To day, various methods have been recommended for As removal that each of which has special advantages and drawbacks. Granular ferric hydroxide (GFH is a relatively new adsorbent available in market which is principally introduced for As removal.MethodsThis study was an applied survey in which the effects of changing contact time, As concentration, adsorbent weight, pH as well as the effect of sulfate and chloride ions in arsenic removal were determined. Moreover, the model of absorption by GFH was studied and compared with Freundlich and Langmuir models. Raw data were analyzed by Excel and SPSS softwares. ResultsResults showed that As adsorption by GFH imitate both the Freundlich and Langmuir equations (with R2 >0.95. Optimum PH was 7.5 and duration of the process about 30 minutes was sufficient for optimum removal of As. It was also found that efficiency of As removal was high when small amounts of adsorbent were used. Furthermore, sulfate and chloride ions in concentrations used in this study had no noticeable effect on As removal and Fe added during process remains in the water more than the standard value (0.3 mg/l.ConclusionAccording to this study, GFH could be considered as a suitable adsorbent for As removal from polluted water resources because of its high performance without any needs to PH adjustment. However, there are few drawbacks such as Fe addition and relatively high initial cost. Keywords: Arsenic, Granular Ferric Hydroxide (GFH, Adsorption, Drinking Water

Experiences and Factors that Influence Potassium Hydroxide Examination by Microscopists.

Science.gov (United States)

Bunyaratavej, Sumanas; Pattanaprichakul, Penvadee; Srisuma, Sorachai; Leeyaphan, Charussri

2016-01-01

Potassium hydroxide（KOH）examination is commonly used in dermatological practice. Despite its simplicity, rapidity, and minimal invasiveness, experience in specimen collection, preparation, and interpretation is extremely important. To determine the ability to interpret KOH examination of six microscopists with different levels of experience within the Department of Dermatology. Six volunteer microscopists, who have different experiences in KOH examination in terms of specimens per week（SPW）, were assigned to prepare and examine 10 unknown slides of skin scrapings. All participants were then paired into three groups and exchanged the slides set to their partner in each group for a second round of slides interpretation. Results of examinations were classified as correct, false negative, false positive, and misinterpretation. The highly experienced microscopists achieved more correct answers than the fairly experienced group in both sessions. There was a significant positive correlation between SPW（r=1.0, Spearman rank, p=0.01）and the correct answers; and a significant negative correlation between SPW and misinterpretation（r= -1.0, Spearman rank, p<0.01）, exclusively for the second session. A small number of volunteer microscopists was enrolled in this study. Experience in routine slide examination and time spent during examination were significant factors for accurate interpretation of KOH examination. Positive correlation between experience and correct answers, and negative correlation between experience and misinterpretation were particularly observed under limited examination time.

Effect of Nitrogen, Potassium, Magnesium and Zinc Sulfates on Yield and Some Characteristics of Biodiesel Produced from Safflower

Directory of Open Access Journals (Sweden)

M. Ranjbar

2012-08-01

Full Text Available In order to evaluate the effect of different amounts of nitrogen fertilizer, potassium sulfate, magnesium sulfate and zinc sulfate on biodiesel produced from safflower, a field experiment was carried out as completely randomized blocks design with three replications, at Research Farm of Shahrekord University in 2010. Treatments included nitrogen fertilizer at three levels (150, 200 and 300 kg/ha, potassium, magnesium and zinc sulfates at 150, 100 and 50 kg/ha, respectively, and control (no fertilizer application. By nourishing the safflower plants, the seed yield and biodiesel traits such as density, iodine value and saponification value were measured. The results showed that the seed yield under treatment of 300 kg/ha nitrogen (913 kg/ha was greater than other treatments. Magnesium sulfate and potassium sulfate produced the highest oil percentage (32.84 and 32.5, respectively. The biodiesel production under utilization of potassium sulfate had greater density, iodine value and saponification value (867.25 kg/m3, 139.7 mg iodine per 100 g oil, and 190.6 mg sodium hydroxide per g oil, respectively compared to other treatments. In general, it was concluded that application of micronutrient fertilizers (especially potassium sulfate improves seed-oil and biodiesel characteristics of safflower.

A Comparative Study of Potassium Hydroxide versus CO2 Laser Vaporization in The Treatment of Female Genital Warts: A Controlled Clinical Trial.

Science.gov (United States)

Asadi, Nasrin; Hemmati, Ensie; Namazi, Golnaz; Jahromi, Mahnaz Pakniat; Sarraf, Zahra; Pazyar, Nader; Salehi, Alireza

2016-07-01

Genital warts are the most common viral sexually transmitted disease affecting 1% of the population. A prospective, open-label controlled trial was performed to compare topical 5% potassium hydroxide (KOH) solution with CO2 laser in the treatment of female genital warts. Seventy patients were enrolled in the study after convenience sampling. Right-sided lesions of the patients were treated by CO2 laser every 3 weeks. The left-sided lesions of the same patients were treated by topical 5% KOH solution twice a day using a toothpick with cotton wrap on the tip. The patients were visited at 3, 6, and 9 weeks after initiation of the treatment and followed up for 6 months after the last visit. Out of seventy patients, sixty three completed the study and were analyzed. A total of 56 KOH treated-patients (88.9%) showed complete response. On the other hand, 56 laser-treated patients (88.9%) presented complete clearing of the lesion. There was not any difference in response to both modalities of treatment. Complications of KOH solution and CO2 laser were 24% and 19% respectively (P>0.05), but serious adverse events were not observed. The patients under KOH treatment displayed a recurrence rate of 11.1% (7 cases), while the same patients with CO2 laser therapy demonstrated a recurrence rate of 7.9% (5 cases) (P=0.54). Topical 5% KOH solution was as effective as CO2 laser in the treatment of female genital warts. There was not any serious complication in the application of KOH solution. This could be used as a new treatment for genital warts. IRCT201412207848N1.

Tunable Diode Laser Atomic Absorption Spectroscopy for Detection of Potassium under Optically Thick Conditions.

Science.gov (United States)

Qu, Zhechao; Steinvall, Erik; Ghorbani, Ramin; Schmidt, Florian M

2016-04-05

Potassium (K) is an important element related to ash and fine-particle formation in biomass combustion processes. In situ measurements of gaseous atomic potassium, K(g), using robust optical absorption techniques can provide valuable insight into the K chemistry. However, for typical parts per billion K(g) concentrations in biomass flames and reactor gases, the product of atomic line strength and absorption path length can give rise to such high absorbance that the sample becomes opaque around the transition line center. We present a tunable diode laser atomic absorption spectroscopy (TDLAAS) methodology that enables accurate, calibration-free species quantification even under optically thick conditions, given that Beer-Lambert's law is valid. Analyte concentration and collisional line shape broadening are simultaneously determined by a least-squares fit of simulated to measured absorption profiles. Method validation measurements of K(g) concentrations in saturated potassium hydroxide vapor in the temperature range 950-1200 K showed excellent agreement with equilibrium calculations, and a dynamic range from 40 pptv cm to 40 ppmv cm. The applicability of the compact TDLAAS sensor is demonstrated by real-time detection of K(g) concentrations close to biomass pellets during atmospheric combustion in a laboratory reactor.

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.

Diagnóstico laboratorial de micoses superficiais e cutâneas: comparação dos métodos do hidróxido de potássio e do calcofluor white Laboratory diagnosis of superficial and cutaneous mycosis: a comparison of the potassium hydroxide and calcofluor white methods

Directory of Open Access Journals (Sweden)

Keith Werneck Brasil

2003-10-01

as effective as KOH. Potassium hydroxide showed 38 (51% positive and 36 (49% negative results. Calcofluor white showed positive results in 35 (47% samples and negative results in 39 (53% samples. CONCLUSION: The data revealed equal efficiency in the two methods evaluated. On the hand, the calcofluor white method requires a laboratory equipped with an immunofluorescence microscope.

Acrylate intercalation and in situ polymerization in iron-, cobalt-, or manganese-substituted nickel hydroxides.

Science.gov (United States)

Vaysse, C; Guerlou-Demourgues, L; Duguet, E; Delmas, C

2003-07-28

A chimie douce route based on successive redox and exchange reactions has allowed us to prepare new hybrid organic-inorganic materials, composed of polyacrylate macromolecules intercalated into layered double hydroxides (LDHs), deriving from Ni(OH)(2). Monomer intercalation and in situ polymerization mechanisms have appeared to be strongly dependent upon the nature of the substituting cation in the slabs. In the case of iron-based LDHs, a phase containing acrylate monomeric intercalates has been isolated and identified by X-ray diffraction and infrared spectroscopy. Second, interslab free-radical polymerization of acrylate anions has been successfully initiated using potassium persulfate. In cobalt- or manganese-based LDHs, one-step polymerization has been observed, leading directly to a material containing polyacrylate intercalate.

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.

Highly Enhanced Photoelectrochemical Water Oxidation Efficiency Based on Triadic Quantum Dot/Layered Double Hydroxide/BiVO ₄ Photoanodes

Energy Technology Data Exchange (ETDEWEB)

Tang, Yanqun; Wang, Ruirui; Yang, Ye; Yan, Dongpeng; Xiang, Xu

2016-08-03

The water oxidation half-reaction is considered to be a bottleneck for achieving highly efficient solar-driven water splitting due to its multiproton-coupled four-electron process and sluggish kinetics. Herein, a triadic photoanode consisting of dual-sized CdTe quantum dots (QDs), Co-based layered double hydroxide (LDH) nanosheets, and BiVO4 particles, that is, QD@LDH@BiVO4, was designed. Two sets of consecutive Type-II band alignments were constructed to improve photogenerated electron-hole separation in the triadic structure. The efficient charge separation resulted in a 2-fold enhancement of the photocurrent of the QD@LDH@BiVO4 photoanode. A significantly enhanced oxidation efficiency reaching above 90% in the low bias region (i.e., E < 0.8 V vs RHE) could be critical in determining the overall performance of a complete photoelectrochemical cell. The faradaic efficiency for water oxidation was almost 90%. The conduction band energy of QDs is -1.0 V more negative than that of LDH, favorable for the electron injection to LDH and enabling a more efficient hole separation. The enhanced photon-to-current conversion efficiency and improved water oxidation efficiency of the triadic structure may result from the non-negligible contribution of hot electrons or holes generated in QDs. Such a band-matching and multidimensional triadic architecture could be a promising strategy for achieving high-efficiency photoanodes by sufficiently utilizing and maximizing the functionalities of QDs.

Method of dissolving metal ruthenium

International Nuclear Information System (INIS)

Tsuno, Masao; Soda, Yasuhiko; Kuroda, Sadaomi; Koga, Tadaaki.

1988-01-01

Purpose: To dissolve and clean metal ruthenium deposited to the inner surface of a dissolving vessel for spent fuel rods. Method: Metal ruthenium is dissolved in a solution of an alkali metal hydroxide to which potassium permanganate is added. As the alkali metal hydroxide used herein there can be mentioned potassium hydroxide, sodium hydroxide and lithium hydroxide can be mentioned, which is used as an aqueous solution from 5 to 20 % concentration in view of the solubility of metal ruthenium and economical merit. Further, potassium permanganate is used by adding to the solution of alkali metal hydroxide at a concentration of 1 to 5 %. (Yoshihara, H.)

Glycine buffered synthesis of layered iron(II)-iron(III) hydroxides (green rusts)

DEFF Research Database (Denmark)

Yin, Weizhao; Huang, Lizhi; Pedersen, Emil Bjerglund

2017-01-01

Layered Fe(II)-Fe(III) hydroxides (green rusts, GRs) are efficient reducing agents against oxidizing contaminants such as chromate, nitrate, selenite, and nitroaromatic compounds and chlorinated solvents. In this study, we adopted a buffered precipitation approach where glycine (GLY) was used...

Structural transformation of nickel hydroxide films during anodic oxidation

Energy Technology Data Exchange (ETDEWEB)

Crocker, Robert W. [Univ. of California, Berkeley, CA (United States); Muller, Rolf H. [Univ. of California, Berkeley, CA (United States)

1992-05-01

The transformation of anodically formed nickel hydroxide/oxy-hydroxide electrodes has been investigated. A mechanism is proposed for the anodic oxidation reaction, in which the reaction interface between the reduced and oxidized phases of the electrode evolves in a nodular topography that leads to inefficient utilization of the active electrode material. In the proposed nodular transformation model for the anodic oxidation reaction, nickel hydroxide is oxidized to nickel oxy-hydroxide in the region near the metal substrate. Since the nickel oxy-hydroxide is considerably more conductive than the surrounding nickel hydroxide, as further oxidation occurs, nodular features grow rapidly to the film/electrolyte interface. Upon emerging at the electrolyte interface, the reaction boundary between the nickel hydroxide and oxy-hydroxide phases spreads laterally across the film/electrolyte interface, creating an overlayer of nickel oxy-hydroxide and trapping uncharged regions of nickel hydroxide within the film. The nickel oxy-hydroxide overlayer surface facilitates the oxygen evolution side reaction. Scanning tunneling microscopy of the electrode in its charged state revealed evidence of 80 - 100 Angstrom nickel oxy-hydroxide nodules in the nickel hydroxide film. In situ spectroscopic ellipsometer measurements of films held at various constant potentials agree quantitatively with optical models appropriate to the nodular growth and subsequent overgrowth of the nickel oxy-hydroxide phase. A two-dimensional, numerical finite difference model was developed to simulate the current distribution along the phase boundary between the charged and uncharged material. The model was used to explore the effects of the physical parameters that govern the electrode behavior. The ratio of the conductivities of the nickel hydroxide and oxy-hydroxide phases was found to be the dominant parameter in the system.

Structural transformation of nickel hydroxide films during anodic oxidation

Energy Technology Data Exchange (ETDEWEB)

Crocker, R.W.; Muller, R.H.

1992-05-01

The transformation of anodically formed nickel hydroxide/oxy-hydroxide electrodes has been investigated. A mechanism is proposed for the anodic oxidation reaction, in which the reaction interface between the reduced and oxidized phases of the electrode evolves in a nodular topography that leads to inefficient utilization of the active electrode material. In the proposed nodular transformation model for the anodic oxidation reaction, nickel hydroxide is oxidized to nickel oxy-hydroxide in the region near the metal substrate. Since the nickel oxy-hydroxide is considerably more conductive than the surrounding nickel hydroxide, as further oxidation occurs, nodular features grow rapidly to the film/electrolyte interface. Upon emerging at the electrolyte interface, the reaction boundary between the nickel hydroxide and oxy-hydroxide phases spreads laterally across the film/electrolyte interface, creating an overlayer of nickel oxy-hydroxide and trapping uncharged regions of nickel hydroxide within the film. The nickel oxy-hydroxide overlayer surface facilitates the oxygen evolution side reaction. Scanning tunneling microscopy of the electrode in its charged state revealed evidence of 80 {endash} 100 Angstrom nickel oxy-hydroxide nodules in the nickel hydroxide film. In situ spectroscopic ellipsometer measurements of films held at various constant potentials agree quantitatively with optical models appropriate to the nodular growth and subsequent overgrowth of the nickel oxy-hydroxide phase. A two-dimensional, numerical finite difference model was developed to simulate the current distribution along the phase boundary between the charged and uncharged material. The model was used to explore the effects of the physical parameters that govern the electrode behavior. The ratio of the conductivities of the nickel hydroxide and oxy-hydroxide phases was found to be the dominant parameter in the system.

Dissolution mechanism of aluminum hydroxides in acid media

Science.gov (United States)

Lainer, Yu. A.; Gorichev, I. G.; Tuzhilin, A. S.; Gololobova, E. G.

2008-08-01

The effects of the concentration, temperature, and potential at the hydroxide/electrolyte interface on the aluminum hydroxide dissolution in sulfuric, hydrochloric, and perchloric acids are studied. The limiting stage of the aluminum hydroxide dissolution in the acids is found to be the transition of the complexes that form on the aluminum hydroxide surface from the solid phase into the solution. The results of the calculation of the acid-base equilibrium constants at the oxide (hydroxide)/solution interface using the experimental data on the potentiometric titration of Al2O3 and AlOOH suspensions are analyzed. A mechanism is proposed for the dissolution of aluminum hydroxides in acid media.

A high-performance carbon derived from corn stover via microwave and slow pyrolysis for supercapacitors

DEFF Research Database (Denmark)

Jin, Hong; wang, Xiaomin; Shen, Yanbin

2014-01-01

Microwave and slow pyrolysis were conducted for converting corn stover to biochar. Chemical agents of sodium hydroxide and potassium hydroxide were used to progressively produce activated carbon. The pore structures and surface area of the samples were characterized by nitrogen adsorption....../desorption at 77 K. The results demonstrated that higher specific surface areas of activated carbons were obtained by microwave pyrolysis combined with potassium hydroxide activation. However, electrochemical measurements showed that the slow pyrolysis biochar treated with 0.05 mol g−1 (potassium hydroxide...

A comparison of a 5% potassium hydroxide solution with a 5-fluorouracil and salicylic acid combination in the treatment of patients with anogenital warts: a randomized, open-label clinical trial.

Science.gov (United States)

Işik, Selda; Koca, Rafet; Sarici, Gülben; Altinyazar, Hilmi Cevdet

2014-09-01

Anogenital warts are caused by human papillomavirus (HPV), over 30 types of which are infectious for the anogenital tract. Without treatment, warts may regress spontaneously, remain unchanged, or increase in number and size. This study compared the efficacy of a topical 5% potassium hydroxide (KOH) solution with that of a topical 0.5% 5-fluorouracil (5-FU) and 10% salicylic acid (SA) combination in the treatment of anogenital warts. Sixty patients were randomly assigned to receive topical KOH or 5-FU + SA. Both groups demonstrated a significant decrease in numbers of lesions (P  0.05). The mean number of lesions decreased from baseline to week 12 from 17.03 ± 12.64 to 3.73 ± 7.30 and from 16.13 ± 12.97 to 3.10 ± 4.90 in the KOH and 5-FU + SA groups, respectively (P  0.05). No serious adverse events were reported. Neither treatment was more efficacious. Safety and ease of application are important goals in treatments for anogenital warts. A 5% KOH solution is a promising alternative treatment because it is effective and inexpensive and causes minimal side effects. © 2014 The International Society of Dermatology.

The effect of calcium hydroxide treatment on the nutritive and feeding value of Albizia procera for growing goats

Energy Technology Data Exchange (ETDEWEB)

Alam, M.R. [Department of Animal Science, Bangladesh Agricultural University, Mymensingh (Bangladesh)]. E-mail: mralam@royalten.net.bd; Kabir, A.K.M.A.; Amin, M.R. [Department of Animal Science, Bangladesh Agricultural University, Mymensingh (Bangladesh); McNeill, D.M. [Faculty of Veterinary Science, University of Sydney, Camden, NSW (Australia)

2005-08-19

Albizia procera (Albizia) is widely planted in Bangladesh for timber and the leaves are also used as forage. In the dry season the leaves are less palatable than in the wet season and this may be a consequence of an excessive content of tannin. Albizia foliage was collected in the wet (June) and dry (January) seasons from six agro-ecological zones across Bangladesh and chemical composition, for tannins in particular, was determined. Variation in the tannin content across the six zones proved to be minimal. However, the concentration of tannins was almost two-fold higher in the dry compared to the wet season. To assess the potential for deactivating the tannins in Albizia so as to improve its nutritive value, leaves were treated with alkali (either calcium hydroxide or potassium carbonate) or polyethylene glycol (PEG). Alkali treatment reduced the concentrations of extractable tannin by as much as 92%. The ability of calcium hydroxide to deactivate tannin was then tested in vivo. Young goats, fed a basal diet of hay and wheat bran, were allocated to 4 equal groups (n = 4 per group) and supplemented with fresh Albizia foliage (at 300 g/kg of the diet) that was either untreated, or treated with either PEG, calcium hydroxide or calcium hydroxide + PEG. The supplements were fed daily for 9 weeks to allow the effects of chemical treatment on intake and growth rate to be defined. In vivo digestibility, nitrogen (N) balance, and microbial N supply were measured over the 5th week. Intakes of feed dry matter (DM) and the digestibility of DM were similar across treatments (mean intake 32 g/(kg LW day), mean DM digestibility 0.63). However, both the PEG and the PEG + calcium hydroxide treatments, compared to the control and calcium hydroxide only treatments, increased N digestibility (0.72, 0.70 versus 0.60, 0.61), N retention (0.43, 0.48 mg N/mg versus 0.26, 0.27 mg N/mg N intake), and microbial N supply (23.7, 21.4 g/day versus 14.2, 12.4 g/day). These increases translated

The effect of calcium hydroxide treatment on the nutritive and feeding value of Albizia procera for growing goats

International Nuclear Information System (INIS)

Alam, M.R.; Kabir, A.K.M.A.; Amin, M.R.; McNeill, D.M.

2005-01-01

Albizia procera (Albizia) is widely planted in Bangladesh for timber and the leaves are also used as forage. In the dry season the leaves are less palatable than in the wet season and this may be a consequence of an excessive content of tannin. Albizia foliage was collected in the wet (June) and dry (January) seasons from six agro-ecological zones across Bangladesh and chemical composition, for tannins in particular, was determined. Variation in the tannin content across the six zones proved to be minimal. However, the concentration of tannins was almost two-fold higher in the dry compared to the wet season. To assess the potential for deactivating the tannins in Albizia so as to improve its nutritive value, leaves were treated with alkali (either calcium hydroxide or potassium carbonate) or polyethylene glycol (PEG). Alkali treatment reduced the concentrations of extractable tannin by as much as 92%. The ability of calcium hydroxide to deactivate tannin was then tested in vivo. Young goats, fed a basal diet of hay and wheat bran, were allocated to 4 equal groups (n = 4 per group) and supplemented with fresh Albizia foliage (at 300 g/kg of the diet) that was either untreated, or treated with either PEG, calcium hydroxide or calcium hydroxide + PEG. The supplements were fed daily for 9 weeks to allow the effects of chemical treatment on intake and growth rate to be defined. In vivo digestibility, nitrogen (N) balance, and microbial N supply were measured over the 5th week. Intakes of feed dry matter (DM) and the digestibility of DM were similar across treatments (mean intake 32 g/(kg LW day), mean DM digestibility 0.63). However, both the PEG and the PEG + calcium hydroxide treatments, compared to the control and calcium hydroxide only treatments, increased N digestibility (0.72, 0.70 versus 0.60, 0.61), N retention (0.43, 0.48 mg N/mg versus 0.26, 0.27 mg N/mg N intake), and microbial N supply (23.7, 21.4 g/day versus 14.2, 12.4 g/day). These increases translated

Research on the removal of radium from uranium effluent by air-aeration hydrated manganese hydroxide adsorption

International Nuclear Information System (INIS)

Zhang Jianguo; Chen Shaoqing; Qi Jing

2002-01-01

In the acidic leaching uranium process, pyrolusite or manganese oxide (MnO 2 ) powder is often used as an oxidizer. In the processed effluent, manganese ion present as a contaminant in addition to U, Ra, Th, As, Zn, Cu, F, SO 4 2- , etc. Manganese ion content is about 100∼200 mg/1 in effluent. In this case, a new process technique can be developed to treat the effluent using the Mn 2+ present in the effluent. The approach is as follows: The effluent is neutralized by lime milk to pH about 11. As a result, most contaminants are precipitated to meet the uranium effluent discharge standards (U, Th, Mn, SO 4 2- etc.), but radium is still present in the effluent. In this process, manganese ion forms manganese hydroxide Mn(OH) 2 . The manganese hydroxide is easily to oxide to form MnO(OH) 2 by air aeration. This hydrated manganese hydroxide complex can then be used to adsorb radium in effluent. The experiments show: (1) Effluent pH, manganese concentration in effluent, and aeration strength and time etc. influence the radium removal efficiency. Under the test conditions, when manganese in effluent is between 100∼300 mg/l, and pH is over 10.5, radium can be reduced to lower 1.11 Bq/1 in the processed effluent. Higher contents of impurity elements such as aluminum, silicon and magnesium in the effluent affect the removal efficiency; (2) Under the experimental conditions, the lime precipitation air-aeration formed hydrated manganese hydroxide complex sludge is stable. There is no obvious release of radium from the adsorbed hydrated manganese hydroxide complex sludge; (3) The current experiments show that hydrated manganese hydroxide complex sludge has a very good re-adsorption ability for removal of radium from uranium effluent. Some experimental parameters have been measured. (author)

Examining the efficiency of muffle furnance-induced alkaline hydrolysis in determining the titanium content of environmental samples containing engineered titanium dioxide particles

Science.gov (United States)

A novel muffle furnace (MF)-based potassium hydroxide (KOH) fusion digestion technique was developed and its comparative digestion and dissolution efficacy for different titanium dioxide nanoparticles (TiO2-NPs)/environmental matrices was evaluated. Digestion of different enviro...

21 CFR 73.2326 - Chromium hydroxide green.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Chromium hydroxide green. 73.2326 Section 73.2326... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2326 Chromium hydroxide green. (a) Identity and specifications.The color additive chromium hydroxide green shall conform in identity and specifications to the...

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) ...

Potassium phthalimide as efficient basic organocatalyst for the synthesis of 3,4-disubstituted isoxazol-5(4H-ones in aqueous medium

Directory of Open Access Journals (Sweden)

Hamzeh Kiyani

2017-01-01

Full Text Available Potassium phthalimide (PPI is employed as an efficient and effective basic organocatalyst for the one-pot three-component reaction of β-oxoesters with hydroxylamine hydrochloride and various aromatic aldehydes. This cyclocondensation reaction was performed in water as an environmentally benign solvent at room temperature giving 3,4-disubstituted isoxazol-5(4H-ones in good to excellent yields. PPI was found to be an effective organocatalyst for the synthesis of isoxazol-5(4H-one system. The advantages of this method are efficiency, clean, easy work-up, high yields, shorter reaction times, inexpensive, and readily available catalyst.

Simultaneous removal of SO{sub 2} and NOx by microwave with potassium permanganate over zeolite

Energy Technology Data Exchange (ETDEWEB)

Zai-shan Wei; He-jingying Niu; Yong-feng Ji [Sun Yat-sen University, Guangzhou (China). School of Environmental Science and Engineering

2009-02-15

Simultaneous sulfur dioxide (SO{sub 2}) and nitrogen oxides (NOx) removal from flue gas can be achieved with high efficiency by microwave with potassium permanganate (KMnO{sub 4}) over zeolite. The experimental results showed that the microwave reactor could be used to oxidation of SO{sub 2} to sulfate with the best desulfurization efficiency of 96.8% and oxidize NOx to nitrates with the best NOx removal efficiency of 98.4%. Microwave accentuates catalytic oxidation treatment, and microwave addition can increase the SO{sub 2} and NOx removal efficiency by 7.2% and 12.2% separately. The addition of zeolite to microwave potassium permanganate increases from 16.5% to 43.5% the microwave removal efficiency for SO{sub 2}, and the NOx removal efficiency from 85.6% to 98.2%. The additional use of potassium permanganate to the microwave zeolite leads to the enhancement of SO{sub 2} removal efficiency up from 53.9% to 95%, and denitrification efficiency up from 85.6% to 98.2%. The optimal microwave power and empty bed residence time (EBRT) on simultaneous desulfurization and denitrification are 259 W and 0.357 s, respectively. SO{sub 2} and NOx were rapidly oxidized in microwave induced catalytic oxidation reaction using potassium permanganate with zeolite being the catalyst and microwave absorbent. 13 refs., 6 figs.

21 CFR 73.1326 - Chromium hydroxide green.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Chromium hydroxide green. 73.1326 Section 73.1326... COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1326 Chromium hydroxide green. (a) Identity. (1) The color additive chromium hydroxide green is principally hydrated chromic sesquioxide (Cr2O3·XH2O...

Effect of Potassium in Calcined Co-Mn-Al Layered Double Hydroxide on the Catalytic Decomposition of N2O

Czech Academy of Sciences Publication Activity Database

Obalová, L.; Karásková, K.; Jirátová, Květa; Kovanda, F.

2009-01-01

Roč. 90, 1-2 (2009), s. 132-140 ISSN 0926-3373 Institutional research plan: CEZ:AV0Z40720504 Keywords : nitrous oxide * catalytic decomposition * potassium promoter Subject RIV: CC - Organic Chemistry Impact factor: 5.252, year: 2009

Potassium Ferrate: A Novel Chemical Warfare Agent Decontaminant

National Research Council Canada - National Science Library

Greene, Russell; von Fahnestock, F. M; Monzyk, Bruce

2004-01-01

..., and/or unsatisfactory CWA destruction efficiencies. Potassium ferrate (K2FeO4) addresses all of these issues through its high oxidation potential, stable shelf life, and benign reduced state, namely iron oxide...

Analysis of barium hydroxide and calcium hydroxide slurry carbonation reactors

International Nuclear Information System (INIS)

Patch, K.D.; Hart, R.P.; Schumacher, W.A.

1980-05-01

The removal of CO 2 from air was investigated by using a continuous-agitated-slurry carbonation reactor containing either barium hydroxide [Ba(OH) 2 ] or calcium hydroxide [Ca(OH) 2 ]. Such a process would be applied to scrub 14 CO 2 from stack gases at nuclear-fuel reprocessing plants. Decontamination factors were characterized for reactor conditions which could alter hydrodynamic behavior. An attempt was made to characterize reactor performance with models assuming both plug flow and various degrees of backmixing in the gas phase. The Ba(OH) 2 slurry enabled increased conversion, but apparently the process was controlled under some conditions by phenomena differing from those observed for carbonation by Ca(OH) 2 . Overall reaction mechanisms are postulated

ALKALI FUSION OF ROSETTA ZIRCON

International Nuclear Information System (INIS)

DAHER, A.

2008-01-01

The decomposition of Rosetta zircon by fusion with different types of alkalis has been investigated. These alkalis include sodium hydroxide, potassium hydroxide and eutectic mixture of both. The influences of the reaction temperature, zircon to alkalis ratio, fusion time and the stirring of the reactant on the fusion reaction have been evaluated. The obtained results favour the decomposition of zircon with the eutectic alkalis mixture by a decomposition efficiency of 96% obtained at 500 0 C after one hour

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.

21 CFR 73.1010 - Alumina (dried aluminum hydroxide).

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Alumina (dried aluminum hydroxide). 73.1010... GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1010 Alumina (dried aluminum hydroxide). (a) Identity. (1) The color additive alumina (dried aluminum hydroxide) is a white, odorless...

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

Oxidation of Dodecanoate Intercalated Iron(II)–Iron(III) Layered Double Hydroxide to Form 2D Iron(III) (Hydr)oxide Layers

DEFF Research Database (Denmark)

Huang, Li‐Zhi; Ayala‐Luis, Karina B.; Fang, Liping

2013-01-01

hydroxide planar layer were preserved during the oxidation, as shown by FTIR spectroscopy. The high positive charge in the hydroxide layer produced by the oxidation of iron(II) to iron(III) is partially compensated by the deprotonation of hydroxy groups, as shown by X‐ray photoelectron spectroscopy...... between the alkyl chains of the intercalated dodecanoate anions play a crucial role in stabilizing the structure and hindering the collapse of the iron(II)–iron(III) (hydr)oxide structure during oxidation. This is the first report describing the formation of a stable planar layered octahedral iron......(III) (hydr)oxide. oxGRC12 shows promise as a sorbent and host for hydrophobic reagents, and as a possible source of single planar layers of iron(III) (hydr)oxide....

21 CFR 872.3250 - Calcium hydroxide cavity liner.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Calcium hydroxide cavity liner. 872.3250 Section... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3250 Calcium hydroxide cavity liner. (a) Identification. A calcium hydroxide cavity liner is a device material intended to be applied to the interior of a...

Evaluation of layered zinc hydroxide nitrate and zinc/nickel double hydroxide salts in the removal of chromate ions from solutions

International Nuclear Information System (INIS)

Bortolaz de Oliveira, Henrique; Wypych, Fernando

2016-01-01

Layered zinc hydroxide nitrate (ZnHN) and Zn/Ni layered double hydroxide salts were synthesized and used to remove chromate ions from solutions at pH 8.0. The materials were characterized by many instrumental techniques before and after chromate ion removal. ZnHN decomposed after contact with the chromate solution, whereas the layered structure of Zn/Ni hydroxide nitrate (Zn/NiHN) and Zn/Ni hydroxide acetate (Zn/NiHA) remained their layers intact after the topotactic anionic exchange reaction, only changing the basal distances. ZnHN, Zn/NiHN, and Zn/NiHA removed 210.1, 144.8, and 170.1 mg of CrO 4 2− /g of material, respectively. Although the removal values obtained for Zn/NiHN and Zn/NiHA were smaller than the values predicted for the ideal formulas of the solids (194.3 and 192.4 mg of CrO 4 2− /g of material, respectively), the measured capacities were higher than the values achieved with many materials reported in the literature. Kinetic experiments showed the removal reaction was fast. To facilitate the solid/liquid separation process after chromium removal, Zn/Ni layered double hydroxide salts with magnetic supports were also synthesized, and their ability to remove chromate was evaluated. - Highlights: • Zinc hydroxide nitrate and Zn/Ni hydroxide nitrate or acetate were synthesized. • The interlayer anions were replaced by chromate anions at pH=8.0. • Only Zn/Ni hydroxide nitrate or acetate have the structure preserved after exchange. • Fast exchange reaction and high capacity of chromate removal were observed. • Magnetic materials were obtained to facilitate the solids removal the from solutions.

Simultaneous removal of SO{sub 2} and NO{sub x} by microwave with potassium permanganate over zeolite

Energy Technology Data Exchange (ETDEWEB)

Wei, Zai-shan; Niu, He-jingying; Ji, Yong-feng [School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275 (China)

2009-02-15

Simultaneous sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) removal from flue gas can be achieved with high efficiency by microwave with potassium permanganate (KMnO{sub 4}) over zeolite. The experimental results showed that the microwave reactor could be used to oxidation of SO{sub 2} to sulfate with the best desulfurization efficiency of 96.8% and oxidize NO{sub x} to nitrates with the best NO{sub x} removal efficiency of 98.4%. Microwave accentuates catalytic oxidation treatment, and microwave addition can increase the SO{sub 2} and NO{sub x} removal efficiency by 7.2% and 12.2% separately. The addition of zeolite to microwave potassium permanganate increases from 16.5% to 43.5% the microwave removal efficiency for SO{sub 2}, and the NO{sub x} removal efficiency from 85.6% to 98.2%. The additional use of potassium permanganate to the microwave zeolite leads to the enhancement of SO{sub 2} removal efficiency up from 53.9% to 95%, and denitrification efficiency up from 85.6% to 98.2%. The optimal microwave power and empty bed residence time (EBRT) on simultaneous desulfurization and denitrification are 259 W and 0.357 s, respectively. SO{sub 2} and NO{sub x} were rapidly oxidized in microwave induced catalytic oxidation reaction using potassium permanganate with zeolite being the catalyst and microwave absorbent. (author)

Stabilize lead and cadmium in contaminated soils using hydroxyapatite and potassium chloride.

Science.gov (United States)

Wang, Li; Li, Yonghua; Li, Hairong; Liao, Xiaoyong; Wei, Binggan; Ye, Bixiong; Zhang, Fengying; Yang, Linsheng; Wang, Wuyi; Krafft, Thomas

2014-12-01

Combination of hydroxyapatite (HAP) and potassium chloride (KCl) was used to stabilize lead and cadmium in contaminated mining soils. Pot experiments of chilli (Capsicum annuum) and rape (Brassica rapachinensis) were used to evaluate the stabilization efficiency. The results were the following: (1) the optimal combination decreased the leachable lead by 83.3 and 97.27 %, and decreased leachable cadmium by 57.82 and 35.96% for soil HF1 and soil HF2, respectively; (2) the total lead and cadmium concentrations in both plants decreased 69 and 44 %, respectively; (3) The total lead and cadmium concentrations in the edible parts of both vegetables also decreased significantly. This study reflected that potassium chloride can improve the stabilization efficiency of hydroxyapatite, and the combination of hydroxyapatite and potassium chloride can be effectively used to remediate lead and cadmium contaminated mining soil.

A Novel Contrast Stain for the Rapid Diagnosis of Pityriasis Versicolor: A Comparison of Chicago Sky Blue 6B Stain, Potassium Hydroxide Mount and Culture.

Science.gov (United States)

Lodha, Nikita; Poojary, Shital Amin

2015-01-01

The mycological study of pityriasis versicolor is usually done by potassium hydroxide (KOH) mount and culture. However, KOH mount lacks a color contrast and requires a trained eye to interpret, while culture is difficult to perform, time consuming and has low sensitivity. Chicago Sky Blue 6B (CSB) is a new contrast stain that highlights the fungal hyphae and spores, blue against a purplish background. This study was done to compare the utility of a novel contrast stain (CSB stain) with KOH mount and culture. Skin scrapings from the lesions of 100 clinically diagnosed cases of P. versicolor were subjected to (1) KOH mount and CSB stain for direct microscopic examination and (2) culture using Sabouraud's dextrose agar. The statistical analysis of CSB stain and culture was done using KOH mount as the reference method, as it is the most commonly performed and practical diagnostic test available for P. versicolor. An interrater reliability analysis using the Cohen's Kappa statistic was performed to determine consistency (agreement) among the different modalities. Direct microscopy with CSB stain, KOH mount and mycological culture showed positive results in 98 (98%), 92 (92%) and 56 (56%) patients, respectively. Using KOH mount as the reference method, CSB stain had a sensitivity of 100% which was significantly higher than culture (60.9%). Statistically significant fair agreement was found between CSB stain and KOH mount (94% with κ=0.38, P < 0.001). Negligible agreement was found between CSB stain and culture (66%, κ=0.199, P = 0.001) as well as between KOH mount and culture (64%, κ=0.051, P = 0.107). CSB staining of skin scrapings is the most sensitive method for the diagnosis of pityriasis versicolor. Due to the distinct contrast provided by CSB, it is easy to perform, rapid and qualitatively superior to KOH mount.

Nucleation and growth kinetics of zirconium hydroxide by precipitation with ammonium hydroxide

International Nuclear Information System (INIS)

Carleson, T.E.; Chipman, N.A.

1987-01-01

The results of a study of the nucleation and growth kinetics of the precipitation of zirconium hydroxide from the reaction of hexafluorozirconate solution with ammonium hydroxide are reported. The McCabe linear growth rate model was used to correlate the results. The growth rate decreased with residence time and supersaturation for studies with 7 residence times (3.5 - 90 minutes and two supersaturation ratios (0.03 - 0.04, and 0.4). The nucleation rate increased with residence time and supersaturation. A negative kinetic order of nucleation was observed that may be due to the inhibition of particle growth by adsorption of reacting species on the crystal surfaces

Evaluation of layered zinc hydroxide nitrate and zinc/nickel double hydroxide salts in the removal of chromate ions from solutions

Energy Technology Data Exchange (ETDEWEB)

Bortolaz de Oliveira, Henrique; Wypych, Fernando, E-mail: wypych@ufpr.br

2016-11-15

Layered zinc hydroxide nitrate (ZnHN) and Zn/Ni layered double hydroxide salts were synthesized and used to remove chromate ions from solutions at pH 8.0. The materials were characterized by many instrumental techniques before and after chromate ion removal. ZnHN decomposed after contact with the chromate solution, whereas the layered structure of Zn/Ni hydroxide nitrate (Zn/NiHN) and Zn/Ni hydroxide acetate (Zn/NiHA) remained their layers intact after the topotactic anionic exchange reaction, only changing the basal distances. ZnHN, Zn/NiHN, and Zn/NiHA removed 210.1, 144.8, and 170.1 mg of CrO{sub 4}{sup 2−}/g of material, respectively. Although the removal values obtained for Zn/NiHN and Zn/NiHA were smaller than the values predicted for the ideal formulas of the solids (194.3 and 192.4 mg of CrO{sub 4}{sup 2−}/g of material, respectively), the measured capacities were higher than the values achieved with many materials reported in the literature. Kinetic experiments showed the removal reaction was fast. To facilitate the solid/liquid separation process after chromium removal, Zn/Ni layered double hydroxide salts with magnetic supports were also synthesized, and their ability to remove chromate was evaluated. - Highlights: • Zinc hydroxide nitrate and Zn/Ni hydroxide nitrate or acetate were synthesized. • The interlayer anions were replaced by chromate anions at pH=8.0. • Only Zn/Ni hydroxide nitrate or acetate have the structure preserved after exchange. • Fast exchange reaction and high capacity of chromate removal were observed. • Magnetic materials were obtained to facilitate the solids removal the from solutions.

Potassium fulvate-modified graft copolymer of acrylic acid onto cellulose as efficient chelating polymeric sorbent.

Science.gov (United States)

Mohamed, Magdy F; Essawy, Hisham A; Ammar, Nabila S; Ibrahim, Hanan S

2017-01-01

Acrylic acid (AA) was graft copolymerized from cellulose (Cell) in presence of potassium fulvate (KF) in order to enhance the chemical activity of the resulting chelating polymer and the handling as well. Fourier transform infrared (FTIR) proved that KF was efficiently inserted and became a permanent part of the network structure of the sorbent in parallel during the grafting copolymerization. Scanning electron microscopy (SEM) revealed intact homogeneous structure with uniform surface. This indicates improvement of the handling, however, it was not the case for the graft copolymer of acrylic acid onto cellulose in absence of KF, which is known to be brittle and lacks mechanical integrity. Effective insertion of this co-interpenetrating agent provided more functional groups, such as OH and COOH, which improved the chelating power of the produced sorbent as found for the removal of Cu 2+ ions from its aqueous solutions (the removal efficiency reached ∼98.9%). Different models were used to express the experimental data. The results corroborated conformity of the pseudo-second order kinetic model and Langmuir isotherm model to the sorption process, which translates into dominance of the chemisorption. Regeneration of the chelating polymers under harsh conditions did not affect the efficiency of copper ions uptake up to three successive cycles. A thermodynamic investigation ensured exothermic nature of the adsorption process that became less favourable at higher temperatures. Copyright © 2016 Elsevier B.V. All rights reserved.

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.

Antimicrobial Activity of Calcium Hydroxide in Endodontics: A Review

Science.gov (United States)

Shalavi, S; Yazdizadeh, M

2012-01-01

The purpose of endodontic therapy is to preserve the patient's natural teeth without compromising the patient's local or systemic health. Calcium hydroxide has been included in several materials and antimicrobial formulations that are used in several treatment modalities in endodontics, such as inter-appointment intracanal medicaments. The purpose of this article was to review the antimicrobial properties of calcium hydroxide in endodontics. Calcium hydroxide has a high pH (approximately 12.5-12.8) and is classified chemically as a strong base. The lethal effects of calcium hydroxide on bacterial cells are probably due to protein denaturation and damage to DNA and cytoplasmic membranes. Calcium hydroxide has a wide range of antimicrobial activity against common endodontic pathogens but is less effective against Enterococcus faecalis and Candida albicans. Calcium hydroxide is also a valuable anti-endotoxin agent. However, its effect on microbial biofilms is controversial. PMID:23323217

NiMn layered double hydroxide nanosheets/NiCo2O4 nanowires with surface rich high valence state metal oxide as an efficient electrocatalyst for oxygen evolution reaction

Science.gov (United States)

Yang, Liting; Chen, Lin; Yang, Dawen; Yu, Xu; Xue, Huaiguo; Feng, Ligang

2018-07-01

High valence transition metal oxide is significant for anode catalyst of proton membrane water electrolysis technique. Herein, we demonstrate NiMn layered double hydroxide nanosheets/NiCo2O4 nanowires hierarchical nanocomposite catalyst with surface rich high valence metal oxide as an efficient catalyst for oxygen evolution reaction. A low overpotential of 310 mV is needed to drive a 10 mA cm-2 with a Tafel slope of 99 mV dec-1, and a remarkable stability during 8 h is demonstrated in a chronoamperometry test. Theoretical calculation displays the change in the rate-determining step on the nanocomposite electrode in comparison to NiCo2O4 nanowires alone. It is found high valence Ni and Mn oxide in the catalyst system can efficiently facilitate the charge transport across the electrode/electrolyte interface. The enhanced electrical conductivity, more accessible active sites and synergistic effects between NiMn layered double hydroxide nanosheets and NiCo2O4 nanowires can account for the excellent oxygen evolution reaction. The catalytic performance is comparable to most of the best non-noble catalysts and IrO2 noble catalyst, indicating the promising applications in water-splitting technology. It is an important step in the development of hierarchical nanocomposites by surface valence state tuning as an alternative to noble metals for oxygen evolution reaction.

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

Trapped electron spectra in hydrates of sodium, potassium and tetraalkylammonium hydroxides of varying H2O content

International Nuclear Information System (INIS)

Zagorski, Z.P.; Grodkowski, J.; Bobrowski, K.

1980-01-01

Transient spectra of e - sub(t) in hydrates at room temperature obtained by pulse radiolysis with Cerenkov L.S.M. are presented. The decrease in number of H 2 O molecules n, in KOH.nH 2 O and NaOH.nH 2 O is accompanied by a blue shift of the absorption maximum. The same tendency is observed in concentrated solutions. The shifts in tetraalkylammonium hydroxides are not as extended as in KOH and NaOH systems, because TAAH's coordinate more H 2 O molecules and the preparation of solution of higher concentration is not possible. Freezing of hydrates does not change the e - sub(t) spectrum considerably. The concept of the trap containing one molecule of water and one electron is discussed in the general context of the phenomena. (author)

Layered zinc hydroxide salts: Delamination, preferred orientation of hydroxide lamellae, and formation of ZnO nanodiscs

Czech Academy of Sciences Publication Activity Database

Demel, Jan; Pleštil, Josef; Bezdička, Petr; Janda, Pavel; Klementová, Mariana; Lang, Kamil

2011-01-01

Roč. 360, č. 2 (2011), s. 532-539 ISSN 0021-9797 R&D Projects: GA MŠk ME09058; GA ČR GAP207/10/1447 Institutional research plan: CEZ:AV0Z40320502; CEZ:AV0Z40500505; CEZ:AV0Z40400503 Keywords : layered zinc hydroxide * delamination * exfoliation * hydroxide layer * ZnO Subject RIV: CA - Inorganic Chemistry Impact factor: 3.070, year: 2011

Hydrocyanation of sulfonylimines using potassium hexacyanoferrate(II) as an eco-friendly cyanide source

International Nuclear Information System (INIS)

Li, Zheng; Li, Rongzhi; Zheng, Huanhuan; Wen, Fei; Li, Hongbo; Yin, Junjun; Yang, Jingya

2013-01-01

An efficient and eco-friendly method for hydrocyanation of sulfonylimines via one-pot two-step procedure using potassium hexacyanoferrate)II) as cyanide source, benzoyl chloride as a promoter, and potassium carbonate as a base is described. This protocol has the features of using nontoxic, nonvolatile and inexpensive cyanide source, high yield, and simple work-up procedure. (author)

Hydrocyanation of sulfonylimines using potassium hexacyanoferrate(II) as an eco-friendly cyanide source

Energy Technology Data Exchange (ETDEWEB)

Li, Zheng; Li, Rongzhi; Zheng, Huanhuan; Wen, Fei; Li, Hongbo; Yin, Junjun; Yang, Jingya, E-mail: lizheng@nwnu.edu.cn [Key Laboratory of Eco-Environment-Related Polymer Materials for Ministry of Education, College of Chemistry and Chemical Engineering, Northwest Normal University, Gansu (China)

2013-11-15

An efficient and eco-friendly method for hydrocyanation of sulfonylimines via one-pot two-step procedure using potassium hexacyanoferrate)II) as cyanide source, benzoyl chloride as a promoter, and potassium carbonate as a base is described. This protocol has the features of using nontoxic, nonvolatile and inexpensive cyanide source, high yield, and simple work-up procedure. (author)

Polysulfide intercalated layered double hydroxides for metal capture applications

Energy Technology Data Exchange (ETDEWEB)

Kanatzidis, Mercouri G.; Ma, Shulan

2017-04-04

Polysulfide intercalated layered double hydroxides and methods for their use in vapor and liquid-phase metal capture applications are provided. The layered double hydroxides comprise a plurality of positively charged host layers of mixed metal hydroxides separated by interlayer spaces. Polysulfide anions are intercalated in the interlayer spaces.

Cadmium hydroxide nanowire loaded on activated carbon as efficient adsorbent for removal of Bromocresol Green

Science.gov (United States)

Ghaedi, Mehrorang; Khajesharifi, Habibollah; Hemmati Yadkuri, Amin; Roosta, Mostafa; Sahraei, Reza; Daneshfar, Ali

2012-02-01

In the present research, cadmium hydroxide nanowire loaded on activated carbon (Cd(OH) 2-NW-AC) was synthesized and characterized. This new adsorbent was applied for the removal of Bromocresol Green (BCG) molecules from aqueous solutions. The influence of effective variables such as solution pH, contact time, initial BCG concentration, amount of Cd(OH) 2-NW-AC and temperature on the adsorption efficiency of BCG in batch system was examined. During all experiments BCG contents were determined by UV-Vis spectrophotometer. Fitting the experimental data to different kinetic models including pseudo-first-order, pseudo-second-order, Elovich and intra-particle diffusion kinetic models show the suitability of the pseudo-second-order kinetic model to interpret in the experimental data. Equilibrium isotherm studies were examined by application of different conventional models such as Langmuir, Freundlich and Tempkin models to explain the experimental data. Based on considering R2 value as criterion the adsorption data well fitted to Langmuir model with maximum adsorption capacity of 108.7 mg g -1. Thermodynamic parameters (Gibb's free energy, entropy and enthalpy) of adsorption were calculated according to general procedure to take some information about the on-going adsorption process. The high negative value of Gibb's free energy and positive value of enthalpy show the feasibility and endothermic nature of adsorption process.

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.

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)

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

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

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.

Calcium hydroxide suppresses Porphyromonas endodontalis lipopolysaccharide-induced bone destruction.

Science.gov (United States)

Guo, J; Yang, D; Okamura, H; Teramachi, J; Ochiai, K; Qiu, L; Haneji, T

2014-05-01

Porphyromonas endodontalis and its main virulence factor, lipopolysaccharide (LPS), are associated with the development of periapical diseases and alveolar bone loss. Calcium hydroxide is commonly used for endodontic therapy. However, the effects of calcium hydroxide on the virulence of P. endodontalis LPS and the mechanism of P. endodontalis LPS-induced bone destruction are not clear. Calcium hydroxide rescued the P. endodontalis LPS-suppressed viability of MC3T3-E1 cells and activity of nuclear factor-κB (NF-κB) in these cells, resulting in the reduced expression of interleukin-6 and tumor necrosis factor-α. In addition, calcium hydroxide inhibited P. endodontalis LPS-induced osteoclastogenesis by decreasing the activities of NF-κB, p38, and ERK1/2 and the expression of nuclear factor of activated T-cell cytoplasmic 1 in RAW264.7 cells. Calcium hydroxide also rescued the P. endodontalis LPS-induced osteoclastogenesis and bone destruction in mouse calvaria. Taken together, our present results indicate that calcium hydroxide suppressed bone destruction by attenuating the virulence of P. endodontalis LPS on bone cells.

Microbial Precipitation of Cr(III)-Hydroxide and Se(0) Nanoparticles During Anoxic Bioreduction of Cr(VI)- and Se(VI)-Contaminated Water.

Science.gov (United States)

Kim, Yumi; Oh, Jong-Min; Roh, Yul

2017-04-01

This study examined the microbial precipitations of Cr(III)-hydroxide and Se(0) nanoparticles during anoxic bioreductions of Cr(VI) and Se(VI) using metal-reducing bacteria enriched from groundwater. Metal-reducing bacteria enriched from groundwater at the Korea Atomic Energy Research Institute (KAERI) Underground Research Tunnel (KURT), Daejeon, S. Korea were used. Metal reduction and precipitation experiments with the metal-reducing bacteria were conducted using Cr(VI)- and Se(VI)-contaminated water and glucose as a carbon source under an anaerobic environment at room temperature. XRD, SEM-EDX, and TEM-EDX analyses were used to characterize the mineralogy, crystal structure, chemistry, shape, and size distribution of the precipitates. The metal-reducing bacteria reduced Cr(VI) of potassium chromate (K₂CrO₄) to Cr(III) of chromium hydroxide [Cr(OH)3], and Se(VI) of sodium selenate (Na₂SeO₄) to selenium Se(0), with changes of color and turbidity. XRD, SEM-EDX, and TEM-EDX analyses revealed that the chromium hydroxide [Cr(OH)₃] was formed extracellularly with nanoparticles of 20–30 nm in size, and elemental selenium Se(0) nanoparticles had a sphere shape of 50–250 nm in size. These results show that metal-reducing bacteria in groundwater can aid or accelerate precipitation of heavy metals such as Cr(VI) and Se(VI) via bioreduction processes under anoxic environments. These results may also be useful for the recovery of Cr and Se nanoparticles in natural environments.

Intercalation studies of zinc hydroxide chloride: Ammonia and amino acids

International Nuclear Information System (INIS)

Arízaga, Gregorio Guadalupe Carbajal

2012-01-01

Zinc hydroxide chloride (ZHC) is a layered hydroxide salt with formula Zn 5 (OH) 8 Cl 2 ·2H 2 O. It was tested as intercalation matrix for the first time and results were compared with intercalation products of the well-known zinc hydroxide nitrate and a Zn/Al layered double hydroxide. Ammonia was intercalated into ZHC, while no significant intercalation occurred in ZHN. Aspartic acid intercalation was only achieved by co-precipitation at pH=10 with ZHC and pH=8 with zinc hydroxide nitrate. Higher pH resistance in ZHC favored total deprotonation of both carboxylic groups of the Asp molecule. ZHC conferred more thermal protection against Asp combustion presenting exothermic peaks even at 452 °C while the exothermic event in ZHN was 366 °C and in the LDH at 276 °C. - Graphical abstract: The zinc hydroxide chloride (ZHC) with formula Zn 5 (OH) 8 Cl 2 ·2H 2 O was tested as intercalation matrix. In comparison with the well-known zinc hydroxide nitrate (ZHN) and layered double hydroxides (LDH), ZHC was the best matrix for thermal protection of Asp combustion, presenting exothermic peaks even at 452 °C, while the highest exothermic event in ZHN was at 366 °C, and in the LDH it was at 276 °C. Highlights: ► Zinc hydroxide chloride (ZHC) was tested as intercalation matrix for the first time. ► ZHC has higher chemical and thermal stability than zinc hydroxide nitrate and LDH. ► NH 3 molecules can be intercalated into ZHC. ► The amino group of amino acids limits the intercalation by ion-exchange.

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.

The effects of fabrication temperature on current-voltage characteristics and energy efficiencies of quantum dot sensitized ZnOH-GO hybrid solar cells

International Nuclear Information System (INIS)

Islam, S. M. Z.; Gayen, Taposh; Tint, Naing; Alfano, Robert; Shi, Lingyan; Seredych, Mykola; Bandosz, Teresa J.

2014-01-01

The effects of fabrication temperature are investigated on the performance of CdSe quantum dot (QD)-sensitized hybrid solar cells of the composite material of zinc (hydr)oxide (ZnOH-GO)with 2 wt. % graphite oxide. The current-voltage (I-V) and photo-current measurements show that higher fabrication temperatures yield greater photovoltaic power conversion efficiencies that essentially indicate more efficient solar cells. Two Photon Fluorescence images show the effects of temperature on the internal morphologies of the solar devices based on such materials. The CdSe-QD sensitized ZnOH-GO hybrid solar cells fabricated at 450 °C showing conversion of ∼10.60% under a tungsten lamp (12.1 mW/cm 2 ) are reported here, while using potassium iodide as an electrolyte. The output photocurrent, I (μA) with input power, P (mW/cm 2 ) is found to be superlinear, showing a relation of I = P n , where n = 1.4.

Final Technical Report on Development of an Economic and Efficient Biodiesel production Process (NC)

Energy Technology Data Exchange (ETDEWEB)

Tirla, Cornelia [Univ. of North Carolina, Pembroke, NC (United States); Dooling, Thomas A. [Univ. of North Carolina, Pembroke, NC (United States); Smith, Rachel B. [Univ. of North Carolina, Pembroke, NC (United States); Shi, Xinyan [Univ. of North Carolina, Pembroke, NC (United States); Shahbazi, Abolghasem [North Carolina Agricultural and Technical State Univ., Greensboro, NC (United States)

2014-03-19

The Biofuels Team at The University of North Carolina at Pembroke and North Carolina A&T State University carried out a joint research project aimed at developing an efficient process to produce biodiesel. In this project, the team developed and tested various types of homogeneous and heterogeneous catalysts which could replace the conventionally used soluble potassium hydroxide catalyst which, traditionally, must be separated and disposed of at the end of the process. As a result of this screening, the homogeneous catalyst choline hydroxide was identified as a potential replacement for the traditional catalyst used in this process, potassium hydroxide, due to its decreased corrosiveness and toxicity. A large number of heterogeneous catalysts were produced and tested in order to determine the scaffold, ion type and ion concentration which would produce optimum yield of biodiesel. The catalyst with 12% calcium on Zeolite β was identified as being highly effective and optimal reaction conditions were identified. Furthermore, a packed bed reactor utilizing this type of catalyst was designed, constructed and tested in order to further optimize the process. An economic analysis of the viability of the project showed that the cost of an independent farmer to produce the fuelstock required to produce biodiesel exceeds the cost of petroleum diesel under current conditions and that therefore without incentives, farmers would not be able to benefit economically from producing their own fuel. An educational website on biodiesel production and analysis was produced and a laboratory experiment demonstrating the production of biodiesel was developed and implemented into the Organic Chemistry II laboratory curriculum at UNCP. Five workshops for local farmers and agricultural agents were held in order to inform the broader community about the various fuelstock available, their cultivation and the process and advantages of biodiesel use and production. This project fits both

Advanced oxidation of rhodamine B with hydrogen peroxide over ZnCr layered double hydroxide catalysts

Directory of Open Access Journals (Sweden)

Nguyen Tien Thao

2017-09-01

Full Text Available Zn/Cr layered zinc hydroxide materials with different molar ratios of Cr/Zn have been synthesized through the coprecipitation method at pH of 9.0–9.5. At high Cr/Zn molar ratios of 0.5/1–1/3, the materials possess some layered structure with carbonate anions between the interlayer galleries. The catalysts present uniform particle sizes and quite high surface area. An isomorphous substitution of Zn2+ by Cr3+ in the brucite-like sheets makes the layered Cr-doped zinc hydroxides potential catalysts for efficient oxidation of rhodamine B with H2O2 solution. The experimental results indicated that the intra-lattice Cr3+ ions are more active than Cr2O3 components in the oxidative removal of rhodamine B. The degradation efficiency is dependent on the intra lattice Cr3+ contents and reaction variables. The Cr/Zn LDH gave a high decolorization (99% of rhodamine B at near neutral pH and room temperature.

Plasmonic photocatalysts based on silver nanoparticles - layered double hydroxides for efficient removal of toxic compounds using solar light

Science.gov (United States)

Gilea, Diana; Radu, Teodora; Muresanu, Mihaela; Carja, Gabriela

2018-06-01

Plasmon-enhanced photocatalysis holds important promise for chemical processes and outcomes. We present here the self-assemblies of silver nanoparticles (AgNP)/layered double hydroxides (LDHs: MeAlLDHs with Me2+ = Zn2+;Mg2+) and their derived AgNP/MMOs (type AgNP/MgAl2O4; AgNP/ZnO/ZnAl2O4) as novel plasmonic photocatalysts exhibiting activity for phenol photodegradation from aqueous solution by solar-light. The fabrication procedure of AgNP/LDHs assemblies is simple and cost effective and is based on the in-situ synthesis of AgNP on the LDHs matrices during the reconstruction of MgAlLDH and ZnAlLDH in the aqueous solution of Ag2SO4. The tested catalysts were thoroughly investigated - techniques to obtain information on their crystalline structure (XRD), surface properties (XPS), morphological features (TEM) and optical properties (UV-vis). The results show that the solar photocatalytic response of the catalysts is ascribed to the plasmonic response of AgNP though the catalytic efficiency is strongly influenced by the composition of the MeAlLDHs. The best photocatalytic performance was obtained on AgNP/ZnAlLDH750 catalyst that degraded 100% of phenol after 80 min of irradiation with solar light. The results reveal the high potential to tailor AgNP/LDHs and AgNP/MMOs as efficient photo-functional plasmonic hybrids for waste-water cleaning.

Crystal structure of the sodium-potassium pump (Na+,K+-ATPase) with bound potassium and ouabain

OpenAIRE

Ogawa, Haruo; Shinoda, Takehiro; Cornelius, Flemming; Toyoshima, Chikashi

2009-01-01

The sodium-potassium pump (Na+,K+-ATPase) is responsible for establishing Na+ and K+ concentration gradients across the plasma membrane and therefore plays an essential role in, for instance, generating action potentials. Cardiac glycosides, prescribed for congestive heart failure for more than 2 centuries, are efficient inhibitors of this ATPase. Here we describe a crystal structure of Na+,K+-ATPase with bound ouabain, a representative cardiac glycoside, at 2.8 Å resolution in a state analog...

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.

Preparation of plate-shape nano-magnesium hydroxide from asbestos tailings

International Nuclear Information System (INIS)

Du Gaoxiang; Zheng Shuilin

2009-01-01

To prepare magnesium hydroxide is one of the effective methods to the comprehensive utilization of asbestos tailings. Nano-scale magnesium hydroxide was prepared and mechanisms of in-situ surface modification were characterized in the paper. Process conditions of preparation of magnesium hydroxide from purified hydrochloric acid leachate of asbestos tailings were optimized and in-situ surface modification of the product was carried out. Results showed that optimum process conditions for preparing nano-scale magnesium hydroxide were as follows: initial concentration of Mg 2+ in the leachate was 22.75g/L, precipitant was NaOH solution (mass concentration 20%), reaction temperature was 50 deg. C, and reaction time was 5min. The diameter and thickness of the plate nano-scale magnesium hydroxide powder prepared under optimal conditions were about 100 nm and 10 nm, respectively. However, particle agglomeration was obvious, the particle size increased to micron-grade. Dispersity of the magnesium hydroxide powder could be elevated by in-situ modification by silane FR-693, titanate YB-502 and polyethylene glycol and optimum dosages were 1.5%, 1.5% and 0.75% of the mass of magnesium hydroxide, respectively. All of the modifiers adsorbed chemically on surfaces of magnesium hydroxide particles, among which Si-O-Mg bonds formed among silane FR-693 and the particle surfaces and Ti-O-Mg among titanate YB-502 and the surfaces.

Synthesis of Platinum-Nickel Hydroxide Nanocomposites for Electrocatalytic Reduction of Water

KAUST Repository

Wang, Lei

2016-11-25

Water electrolysis represents a promising solution for storage of renewable but intermittent electrical energy in hydrogen molecules. This technology is however challenged by the lack of efficient electrocatalysts for the hydrogen and oxygen evolution reactions. Here we report on the synthesis of platinum-nickel hydroxide nanocomposites and their electrocatalytic applications for water reduction. An in situ reduction strategy taking advantage of the Ni(II)/Ni(III) redox has been developed to enable and regulate the epitaxial growth of Pt nanocrystals on single-layer Ni(OH)2 nanosheets. The obtained nanocomposites (denoted as Pt@2D-Ni(OH)2) exhibit an improvement factor of 5 in catalytic activity and a reduction of up to 130 mV in overpotential compared to Pt for the hydrogen evolution reaction (HER). A combination of electron microscopy/spectroscopy characterization, electrochemical studies and density functional calculations was employed to uncover the structures of the metal-hydroxide interface and understand the mechanisms of catalytic enhancement.

Synthesis of Platinum-Nickel Hydroxide Nanocomposites for Electrocatalytic Reduction of Water

KAUST Repository

Wang, Lei; Zhu, Yihan; Zeng, Zhenhua; Lin, Chong; Giroux, Michael; Jiang, Lin; Han, Yu; Greeley, Jeffrey; Wang, Chao; Jin, Jian

2016-01-01

Water electrolysis represents a promising solution for storage of renewable but intermittent electrical energy in hydrogen molecules. This technology is however challenged by the lack of efficient electrocatalysts for the hydrogen and oxygen evolution reactions. Here we report on the synthesis of platinum-nickel hydroxide nanocomposites and their electrocatalytic applications for water reduction. An in situ reduction strategy taking advantage of the Ni(II)/Ni(III) redox has been developed to enable and regulate the epitaxial growth of Pt nanocrystals on single-layer Ni(OH)2 nanosheets. The obtained nanocomposites (denoted as Pt@2D-Ni(OH)2) exhibit an improvement factor of 5 in catalytic activity and a reduction of up to 130 mV in overpotential compared to Pt for the hydrogen evolution reaction (HER). A combination of electron microscopy/spectroscopy characterization, electrochemical studies and density functional calculations was employed to uncover the structures of the metal-hydroxide interface and understand the mechanisms of catalytic enhancement.

Electrochemical potassium-ion intercalation in NaxCoO2: a novel cathode material for potassium-ion batteries.

Science.gov (United States)

Sada, Krishnakanth; Senthilkumar, Baskar; Barpanda, Prabeer

2017-07-27

Reversible electrochemical potassium-ion intercalation in P2-type Na x CoO 2 was examined for the first time. Hexagonal Na 0.84 CoO 2 platelets prepared by a solution combustion synthesis technique were found to work as an efficient host for K + intercalation. They deliver a high reversible capacity of 82 mA h g -1 , good rate capability and excellent cycling performance up to 50 cycles.

Protein-lipid interactions in concentrated infant formula

International Nuclear Information System (INIS)

Rowley, B.O.; Richardson, T.

1985-01-01

Radiolabeled milk proteins ([carbon-14] β-lactoglobulin or [carbon-14] kappa-casein) were added to raw skim milk used to prepare concentrated humanized infant formula. Ultracentrifugation of the sterilized product allowed separation of three fractions: lipids and the proteins associated with them; free casein micelles and other dense particles; and the fluid phase. Distribution of radiolabeled tracer proteins or of protein measured by chemical methods among these three phases varied significantly with differences in processing conditions (time and temperature of sterilization) or amount of certain additives (potassium hydroxide or urea). In the range of 0 to 8 meq/L of potassium hydroxide added to the formula after homogenization but before sterilization, the lipid layer content of carbon-14 from [carbon-14] kappa-casein in the sterilized product decreased by 4.7% for each 1 meq/L of added potassium hydroxide. Lipid layer content of protein decreased by 2 g/L ( of a total of 32 g/L) for each 1 meq/L potassium hydroxide

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...

Nickel and cobalt bimetallic hydroxide catalysts for urea electro-oxidation

International Nuclear Information System (INIS)

Yan Wei; Wang Dan; Botte, Gerardine G.

2012-01-01

Nickel–Cobalt bimetallic hydroxide electrocatalysts, synthesized through a one-step electrodeposition method, were evaluated for the oxidation of urea in alkaline conditions with the intention of reducing the oxidation overpotential for this reaction. The Nickel–Cobalt bimetallic hydroxide catalysts were characterized by scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDXS), Raman spectroscopy, cyclic voltammetry (CV), and polarization techniques. A significant reduction in the overpotential (150 mV) of the reaction was observed with the Nickel–Cobalt bimetallic hydroxide electrode (ca. 43% Co content) when compared to a nickel hydroxide electrode. The decrease of the urea oxidation potential on the Nickel–Cobalt bimetallic hydroxide electrodes reveals great potential for future applications of urea electro-oxidation, including wastewater remediation, hydrogen production, sensors, and fuel cells.

Evaluation of layered zinc hydroxide nitrate and zinc/nickel double hydroxide salts in the removal of chromate ions from solutions

Science.gov (United States)

de Oliveira, Henrique Bortolaz; Wypych, Fernando

2016-11-01

Layered zinc hydroxide nitrate (ZnHN) and Zn/Ni layered double hydroxide salts were synthesized and used to remove chromate ions from solutions at pH 8.0. The materials were characterized by many instrumental techniques before and after chromate ion removal. ZnHN decomposed after contact with the chromate solution, whereas the layered structure of Zn/Ni hydroxide nitrate (Zn/NiHN) and Zn/Ni hydroxide acetate (Zn/NiHA) remained their layers intact after the topotactic anionic exchange reaction, only changing the basal distances. ZnHN, Zn/NiHN, and Zn/NiHA removed 210.1, 144.8, and 170.1 mg of CrO42-/g of material, respectively. Although the removal values obtained for Zn/NiHN and Zn/NiHA were smaller than the values predicted for the ideal formulas of the solids (194.3 and 192.4 mg of CrO42-/g of material, respectively), the measured capacities were higher than the values achieved with many materials reported in the literature. Kinetic experiments showed the removal reaction was fast. To facilitate the solid/liquid separation process after chromium removal, Zn/Ni layered double hydroxide salts with magnetic supports were also synthesized, and their ability to remove chromate was evaluated.

Iodine Sequestration Using Delafossites and Layered Hydroxides

International Nuclear Information System (INIS)

J.D. Pless; J.B. Chwirka; J.L. Krumhansl

2006-01-01

The objective of this document is to report on early success for sequestering 129 I. Sorption coefficients (K d ) for I - and IO 3 - onto delafossites, spinels and layered metal hydroxides were measured in order to compare their applicability for sequestering 129 I. The studies were performed using a dilute fluid composition representative of groundwater indigenous to the Yucca mountain area. Delafossites generally exhibited relatively poor sorption coefficients ( 1.7 mL/g). In contrast, the composition of the layered hydroxides significantly affects their ability to sorb I. Cu/Al and Cu/Cr layered hydroxide samples exhibit K d 's greater than 10 3 mL/g for both I - and IO 3 -

Electrolyte Chemistry for Simultaneous Stabilization of Potassium Metal and Superoxide in K-O₂ Batteries.

Science.gov (United States)

Xiao, Neng; Gourdin, Gerald; Wu, Yiying

2018-05-22

In the superoxide batteries based on O2/O2- redox chemistry, identifying an electrolyte to stabilize both alkali metal and superoxide remains challenging due to their reactivity towards electrolyte components. Bis(fluorosulfonyl)imide (FSI-) has been recognized as a "magical anion" for passivating alkali metals. Herein, we illustrate the chemical reactions between FSI- and superoxide, and the resultant dilemma when considering an anode-compatible electrolyte vs. a cathode-compatible one in K-O2 batteries. On one side, the KFSI-dimethoxyethane (DME) electrolyte passivates the potassium metal anode via the cleavage of S-F bond and formation of a KF-rich solid electrolyte interface (SEI). Nevertheless, the KFSI salt is chemically unstable due to the nucleophilic attack by superoxide and/or hydroxide species. On the other hand, potassium bis(trifluorosulfonyl)imide (KTFSI) is stable for KO2, but results in mossy deposition and irreversible plating and stripping. In order to circumvent this dilemma, we develop an artificial SEI for K metal anode to achieve long cycle-life K-O2 batteries. This work contributes to the understanding of electrolyte chemistry and guides the development of stable electrolytes and artificial SEI in metal-O2 batteries. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nickel-cobalt hydroxide nanosheets: Synthesis, morphology and electrochemical properties

Czech Academy of Sciences Publication Activity Database

Schneiderová, Barbora; Demel, Jan; Zhigunov, Alexander; Bohuslav, Jan; Tarábková, Hana; Janda, Pavel; Lang, Kamil

2017-01-01

Roč. 499, AUG (2017), s. 138-144 ISSN 0021-9797 Institutional support: RVO:61388980 ; RVO:61389013 ; RVO:61388955 Keywords : Hydroxide nanosheets * Delamination * Exfoliation * Layered nickel hydroxide * Layered cobalt hydroxide * Electrode material Subject RIV: CA - Inorganic Chemistry; CF - Physical ; Theoretical Chemistry (UFCH-W); CD - Macromolecular Chemistry (UMCH-V) OBOR OECD: Inorganic and nuclear chemistry; Physical chemistry (UFCH-W); Polymer science (UMCH-V) Impact factor: 4.233, year: 2016

Aluminum hydroxide issue closure package

International Nuclear Information System (INIS)

Bergman, T.B.

1998-01-01

Aluminum hydroxide coatings on fuel elements stored in aluminum canisters in K West Basin were measured in July and August 1998. Good quality data was produced that enabled statistical analysis to determine a bounding value for aluminum hydroxide at a 99% confidence level. The updated bounding value is 10.6 kg per Multi-Canister Overpack (MCO), compared to the previously estimated bounding value of 8 kg/MCO. Thermal analysis using the updated bounding value, shows that the MCO generates oxygen concentrate that are below the lower flammability limits during the 40-year interim storage period and are, therefore, acceptable

Benign and efficient preparation of thioethers by solvent-free S-alkylation of thiols with alkyl halides catalyzed by potassium fluoride on alumina

DEFF Research Database (Denmark)

Nguyen, Kha Ngoc; Duus, Fritz; Luu, Thi Xuan Thi

2016-01-01

The preparation of thioethers by S-alkylation of various thiols with alkyl halides under solvent-free reaction conditions using potassium fluoride on alumina (KF/Al2O3) as a solid catalyst has been investigated in detail with respect to three different modes of reaction activation (ultrasound...... irradiation, microwave irradiation, and conventional heating) for obtaining maximum yield of the thioether. The importance of KF/Al2O3 as a particularly efficient catalyst was corroborated for all three modes of reaction activation, although the reaction time was found to be strongly dependent on the mode...

Aluminium hydroxide-induced granulomas in pigs

DEFF Research Database (Denmark)

Valtulini, S; Macchi, C; Ballanti, P

2005-01-01

The effect of intramuscular injection of 40 mg/2 ml aluminium hydroxide in the neck of pigs was examined in a number of ways. The investigation followed repeated slaughterhouse reports, according to which 64.8% of pigs from one particular farm were found at slaughter to have one or more nodules...... in the muscles of the neck (group slaughtered). The pigs had been injected with a vaccine containing 40 mg/2 ml dose of aluminium hydroxide as adjuvant. Research consisted of two phases: first, an epidemiological study was carried out, aimed at determining the risk factors for the granulomas. The results...... and adjuvant) to pigs inoculated twice with apyrogenic bi-distilled water (group water) and to pigs inoculated once with the adjuvant and once with apyrogenic bi-distilled water (group adjuvant/water). Both studies agreed in their conclusions, which indicate that the high amount of aluminium hydroxide...

Behavior of hydroxide at the water/vapor interface

Science.gov (United States)

Winter, Bernd; Faubel, Manfred; Vácha, Robert; Jungwirth, Pavel

2009-06-01

Hydroxide and hydronium, which represent the ionic products of water autolysis, exhibit a peculiar surface behavior. While consensus has been established that the concentration of hydronium cations is enhanced at the surface with respect to the bulk, the affinity of hydroxide anions for the water/vapor interface has been a subject of an ongoing controversy. On the one hand, electrophoretic and titration measurements of air bubbles or oil droplets in water have been interpreted in terms of a dramatic interfacial accumulation of OH -. On the other hand, surface-selective non-linear spectroscopies, surface tension measurements, and molecular simulations show no or at most a weak surface affinity of hydroxide ions. Here, we summarize the current situation and provide new evidence for the lack of appreciable surface enhancement of OH -, based on photoelectron spectroscopy from a liquid jet and on molecular dynamics simulations with polarizable potentials at varying hydroxide concentrations.

Antimony removal from aqueous solutions using Zirconium hydroxide

International Nuclear Information System (INIS)

Petrescu, D.; Velciu, L.; Bucur, C.

2016-01-01

In this paper it is presented an experimental test for non-radioactive antimony removal from aqueous solutions using zirconium hydroxide powder. Also, it was studied how the temperature and pH influences antimony adsorption onto zirconium hydroxide surface. After the adsorption, solutions were filtered on Cellulose Mixed Ester Membrane with 0.2 μm pore size to remove the zirconium powder and then the aqueous solutions were sent to Inductively Coupled Plasma Optic Emission Spectrometry (ICP-OES) for quantitative analysis of Sb. Zirconium hydroxide powders were examined by optical microscopy. For the solutions that were tested at pH 4.5 and 10.2 the antimony concentration dropped below the detection limit of ICP-OES device, proof of antimony adsorption on zirconium hydroxide. Also, for the other tested solutions which had pH=12 the antimony concentration reduced with 77% and 80%. The temperature had no influence upon adsorption mechanism. (authors)

Layered double hydroxides

DEFF Research Database (Denmark)

López Rayo, Sandra; Imran, Ahmad; Hansen, Hans Chr. Bruun

2017-01-01

A novel zinc (Zn) fertilizer concept based on Zn doped layered double hydroxides (Zn-doped Mg-Fe-LDHs) has been investigated. Zn-doped Mg-Fe-LDHs were synthetized, their chemical composition was analyzed and their nutrient release was studied in buffered solutions with different pH values. Uptake...

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 ...

A novel contrast stain for the rapid diagnosis of pityriasis versicolor: A comparison of Chicago Sky Blue 6B stain, potassium hydroxide mount and culture

Directory of Open Access Journals (Sweden)

Nikita Lodha

2015-01-01

Full Text Available Background: The mycological study of pityriasis versicolor is usually done by potassium hydroxide (KOH mount and culture. However, KOH mount lacks a color contrast and requires a trained eye to interpret, while culture is difficult to perform, time consuming and has low sensitivity. Chicago Sky Blue 6B (CSB is a new contrast stain that highlights the fungal hyphae and spores, blue against a purplish background. Aims and Objectives: This study was done to compare the utility of a novel contrast stain (CSB stain with KOH mount and culture. Materials and Methods: Skin scrapings from the lesions of 100 clinically diagnosed cases of P. versicolor were subjected to (1 KOH mount and CSB stain for direct microscopic examination and (2 culture using Sabouraud′s dextrose agar. The statistical analysis of CSB stain and culture was done using KOH mount as the reference method, as it is the most commonly performed and practical diagnostic test available for P. versicolor. An interrater reliability analysis using the Cohen′s Kappa statistic was performed to determine consistency (agreement among the different modalities. Observations and Results: Direct microscopy with CSB stain, KOH mount and mycological culture showed positive results in 98 (98%, 92 (92% and 56 (56% patients, respectively. Using KOH mount as the reference method, CSB stain had a sensitivity of 100% which was significantly higher than culture (60.9%. Statistically significant fair agreement was found between CSB stain and KOH mount (94% with κ=0.38, P < 0.001. Negligible agreement was found between CSB stain and culture (66%, κ=0.199, P = 0.001 as well as between KOH mount and culture (64%, κ=0.051, P = 0.107. Conclusion: CSB staining of skin scrapings is the most sensitive method for the diagnosis of pityriasis versicolor. Due to the distinct contrast provided by CSB, it is easy to perform, rapid and qualitatively superior to KOH mount.

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.

Single sheet metal oxides and hydroxides

DEFF Research Database (Denmark)

Huang, Lizhi

The synthesis of layered double hydroxides (LDHs) provides a relatively easy and traditional way to build versatile chemical compounds with a rough control of the bulk structure. The delamination of LDHs to form their single host layers (2D nanosheets) and the capability to reassemble them offer......) Delamination of the LDHs structure (oxGRC12) with the formation of single sheet iron (hydr)oxide (SSI). (3) Assembly of the new 2D nanosheets layer by layer to achieve desired functionalities....

Synthesis of polymer nanocomposites using layered hydroxide salts (LHS)

International Nuclear Information System (INIS)

Machado, Paula F. de M.P.B.; Lona, Liliane M.F.; Marangoni, Rafael; Wypych, Fernando

2011-01-01

In this work latexes of poly (methyl methacrylate) were synthesized via emulsion polymerization using layered hydroxide salts (LHS) as reinforcements: zinc hydroxide nitrate (Zn 5 (OH) 8 (NO 3 ) 2 ·2H 2 O) and copper hydroxide acetate (Cu 2 (OH) 3 CH 3 COO.H 2 O). The LHSs were characterized by X-ray powder diffraction (XRPD). Mastersizer analysis indicated the particle diameter of the latexes. Molecular weights and conversion data were also obtained. (author)

Discharge Characteristics of the Nickel Hydroxide Electrode in 30% KOH

International Nuclear Information System (INIS)

Kim, Young Jin

1989-01-01

The discharge behavior of the nickel hydroxide electrode has been investigated in 30% KOH at 25 .deg. C. Two voltage plateaus are displayed on the discharge curve of C/20. It is shown that the impedance of the nickel hydroxide electrode increases with decrease of the discharge potential. The discharge behavior of the nickel hydroxide electrode has been investigated in 30% KOH indicating the reduction of the β-NiOOH to the β-Ni(OH) 2 by proton diffusion process and hence the electronic conductivity change of the nickel hydroxide electrode. Furthermore, the γ-NiOOH, produced by prolonged oxidation of the β-NiOOH in 30% KOH, discharges at a slightly lower potential than the β-Ni(OH) 2 that could result in the life-limiting factor of several alkaline electrolyte storage batteries using the nickel hydroxide electrode as the positive plate

Adsorption of procion red using layer double hydroxide Mg/Al

Directory of Open Access Journals (Sweden)

Muhammad Imron

2017-07-01

Full Text Available Layer double hydroxide Mg/Al was synthesized by inorganic synthetic method. Material was characterized using FTIR and XRD analyses and used as adsorbent of procion red dye in aqueous medium.  Factors that affect the adsorption process are adsorption time as the kinetic parameter; and the temperature and concentration of procion red as the thermodynamic parameter. FTIR spectra of layer double hydroxides showed unique vibration at wavenumber 1300 cm-1 and 1600 cm-1. Characterization using XRD shows diffraction angles at 29o, 27o, and 28o, which are typical of Mg/Al double layer hydroxides. Adsorption of procion red using layer double hydroxide Mg/Al resulted adsorption rate 7.1 minutes-1, maximum adsorption capacity 111.1 mg/g at 60 oC with increasing energy by increasing adsorption temperature.   Keywords: Layered double hydroxides, adsorption, procion red.

Intercalation studies of zinc hydroxide chloride: Ammonia and amino acids

Science.gov (United States)

Arízaga, Gregorio Guadalupe Carbajal

2012-01-01

Zinc hydroxide chloride (ZHC) is a layered hydroxide salt with formula Zn5(OH)8Cl2·2H2O. It was tested as intercalation matrix for the first time and results were compared with intercalation products of the well-known zinc hydroxide nitrate and a Zn/Al layered double hydroxide. Ammonia was intercalated into ZHC, while no significant intercalation occurred in ZHN. Aspartic acid intercalation was only achieved by co-precipitation at pH=10 with ZHC and pH=8 with zinc hydroxide nitrate. Higher pH resistance in ZHC favored total deprotonation of both carboxylic groups of the Asp molecule. ZHC conferred more thermal protection against Asp combustion presenting exothermic peaks even at 452 °C while the exothermic event in ZHN was 366 °C and in the LDH at 276 °C.

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

On reactions of polymerization of p-element hydroxides in aqueous solutions

International Nuclear Information System (INIS)

Tikavyj, V.F.; Lesnikovich, A.I.

1978-01-01

The tendency of p-element hydroxides towards polymerization in aqueous solutions has been considered with respect to their location in the Periodic Table. Stable hydroxides of d-elements are practically all polymerized; among s-elements only berillium and magnesium hydroxides polymerize as the least dissociated ones. Hydroxides of the elements located to the right of the 4 Group and above the 5-th Period do not polymerize in aqueous solutions. The structure and tendency towards polymerization of In, Te, and I compounds have been studied. The tendency to polymerization of all hydroxides of p-elements located below the 4-th Period is explained from the standpoint of electron structure and the simplest thermodynamic analysis (entropy, enthalpy)

Potassium vapor assisted preparation of highly graphitized hierarchical porous carbon for high rate performance supercapacitors

Science.gov (United States)

Liu, Zheng; Zeng, Ying; Tang, Qunli; Hu, Aiping; Xiao, Kuikui; Zhang, Shiying; Deng, Weina; Fan, Binbin; Zhu, Yanfei; Chen, Xiaohua

2017-09-01

Ultrahigh graphitized carbon microspheres with rich hierarchical pores (AGHPCM-1) have been successfully synthesized through the one-step activation-carbonization strategy (OACS) with porous sulfonated poly-divinylbenzene as the carbon precursor, iron as the hard template and catalyst, and potassium hydroxide (KOH) as activation agent. Through the XRD, TEM, Raman and BET analysis, AGHPCM-1 shows very high graphitization degree and rich micro-, meso- and macro-pores. More importantly, the mechanism for KOH to improve the graphitization degree of carbon materials in OACS has been illustrated by the thermodynamical theory. The tremendous heat releasing from the reaction between the catalyst precursor of Fe2O3 and potassium vapor plays a key role in the formation of graphitized carbon. It may provide a general direction to prepare highly graphitized porous carbon at a moderate temperature. Integrating the advantages of high graphitization degree and rich hierarchical porous structure, the AGHPCM-1 exhibits an excellent rate performance with a response to up to the high current density of 150 A g-1 and high scan rate of 2000 mV s-1. No obvious capacitance decay can be observed after 10000 charge/discharge cycles even at the high current density of 20 A g-1.

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

A regenerable potassium and phosphate sorbent system to enhance dialysis efficacy and device portability: a study in awake goats.

Science.gov (United States)

Wester, Maarten; Gerritsen, Karin G; Simonis, Frank; Boer, Walther H; Hazenbrink, Diënty H; Vaessen, Koen R; Verhaar, Marianne C; Joles, Jaap A

2017-06-01

Patients on standard intermittent haemodialysis suffer from strong fluctuations in plasma potassium and phosphate. Prolonged dialysis with a wearable device, based on continuous regeneration of a small volume of dialysate using ion exchangers, could moderate these fluctuations and offer increased clearance of these electrolytes. We report in vivo results on the efficacy of potassium and phosphate adsorption from a wearable dialysis device. We explore whether equilibration of ion exchangers at physiological Ca 2+ , Mg 2+ and hypotonic NaCl can prevent calcium/magnesium adsorption and net sodium release, respectively. Effects on pH and HCO3- were studied. Healthy goats were instrumented with a central venous catheter and dialysed. Potassium and phosphate were infused to achieve plasma concentrations commonly observed in dialysis patients. An adsorption cartridge containing 80 g sodium poly(styrene-divinylbenzene) sulphonate and 40 g iron oxide hydroxide beads for potassium and phosphate removal, respectively, was incorporated in a dialysate circuit. Sorbents were equilibrated and regenerated with a solution containing NaCl, CaCl 2 and MgCl 2 . Blood was pumped over a dialyser and dialysate was recirculated over the adsorption cartridge in a countercurrent direction. Potassium and phosphate adsorption was 7.7 ± 2.7 and 4.9 ± 1.3 mmol in 3 h, respectively. Adsorption capacity remained constant during consecutive dialysis sessions and increased with increasing K + and PO43-. Equilibration at physiological Ca 2+ and Mg 2+ prevented net adsorption, eliminating the need for post-cartridge calcium and magnesium infusion. Equilibration at hypotonic NaCl prevented net sodium release Fe 2+ and arterial pH did not change. Bicarbonate was adsorbed, which could be prevented by equilibrating at HCO3- 15 mM. We demonstrate clinically relevant, concentration-dependent, pH-neutral potassium and phosphate removal in vivo with small volumes of regenerable ion exchangers in our

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.

Potassium-induced surface modification of Cu(In,Ga)Se2 thin films for high-efficiency solar cells.

Science.gov (United States)

Chirilă, Adrian; Reinhard, Patrick; Pianezzi, Fabian; Bloesch, Patrick; Uhl, Alexander R; Fella, Carolin; Kranz, Lukas; Keller, Debora; Gretener, Christina; Hagendorfer, Harald; Jaeger, Dominik; Erni, Rolf; Nishiwaki, Shiro; Buecheler, Stephan; Tiwari, Ayodhya N

2013-12-01

Thin-film photovoltaic devices based on chalcopyrite Cu(In,Ga)Se2 (CIGS) absorber layers show excellent light-to-power conversion efficiencies exceeding 20%. This high performance level requires a small amount of alkaline metals incorporated into the CIGS layer, naturally provided by soda lime glass substrates used for processing of champion devices. The use of flexible substrates requires distinct incorporation of the alkaline metals, and so far mainly Na was believed to be the most favourable element, whereas other alkaline metals have resulted in significantly inferior device performance. Here we present a new sequential post-deposition treatment of the CIGS layer with sodium and potassium fluoride that enables fabrication of flexible photovoltaic devices with a remarkable conversion efficiency due to modified interface properties and mitigation of optical losses in the CdS buffer layer. The described treatment leads to a significant depletion of Cu and Ga concentrations in the CIGS near-surface region and enables a significant thickness reduction of the CdS buffer layer without the commonly observed losses in photovoltaic parameters. Ion exchange processes, well known in other research areas, are proposed as underlying mechanisms responsible for the changes in chemical composition of the deposited CIGS layer and interface properties of the heterojunction.

Rapid collection of iron hydroxide for determination of Th isotopes in seawater

Energy Technology Data Exchange (ETDEWEB)

Okubo, Ayako, E-mail: okubo.ayako@jaea.go.jp [Japan Atomic Energy Agency, Research Group for Analytical Chemistry (Japan); Obata, Hajime, E-mail: obata@aori.u-tokyo.ac.jp [Atmosphere Ocean Research Institute, The University of Tokyo (Japan); Magara, Masaaki, E-mail: magara.masaaki@jaea.go.jp [Japan Atomic Energy Agency, Research Group for Analytical Chemistry (Japan); Kimura, Takaumi, E-mail: kimura.takaumi@jaea.go.jp [Japan Atomic Energy Agency, Research Group for Analytical Chemistry (Japan); Ogawa, Hiroshi, E-mail: hogawa@aori.u-tokyo.ac.jp [Atmosphere Ocean Research Institute, The University of Tokyo (Japan)

2013-12-04

Graphical abstract: -- Highlights: •DIAION CR-20 chelating resin has successfully collected iron-hydroxide with Th isotopes. •Ferric ions in the iron hydroxide were bonded to functional groups of the chelating resin. •The time of preconcentration step was markedly reduced from a few days to 3–4 h. -- Abstract: This work introduces a novel method of recovery of iron hydroxide using a DIAION CR-20 chelating resin column to determine Th isotopes in seawater with a sector field (SF) inductively coupled plasma mass spectrometer (ICP-MS). Thorium isotopes in seawater were co-precipitated with iron hydroxide, and this precipitate was sent to chelating resin column. Ferric ions in the iron hydroxide were bonded to functional groups of the chelating resin directly, resulting in a pH increase of the effluent by release of hydroxide ion from the iron hydroxide. The co-precipitated thorium isotopes were quantitatively collected within the column, which indicated that thorium was retained on the iron hydroxide remaining on the chelating column. The chelating column quantitatively collected {sup 232}Th with iron hydroxide in seawater at flow rates of 20–25 mL min{sup −1}. Based on this flow rate, a 5 L sample was processed within 3–4 h. The >20 h aging of iron hydroxide tends to reduce the recovery of {sup 232}Th. The rapid collection method was successfully applied to the determination of {sup 230}Th and {sup 232}Th in open-ocean seawater samples.

Acid mine water neutralisation with ammonium hydroxide and ...

African Journals Online (AJOL)

This study showed that NH4OH can be used for treatment of acid mine drainage rich in sulphates and NH4OH can be recycled in the process. Hydrated lime treatment resulted in removal of the remaining ammonia using a rotary evaporator. Keywords: acid mine water, ammonium hydroxide, barium hydroxide, sulphate ...

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- ...

Real-time monitoring of arsenic filtration by granular ferric hydroxide

International Nuclear Information System (INIS)

Fleming, D.E.B.; Eddy, I.S.; Gherase, M.R.; Gibbons, M.K.; Gagnon, G.A.

2008-01-01

Full text: Contamination of drinking water by arsenic is a serious public health issue in many parts of the world. One recent approach to this problem has been to filter out arsenic by use of granular ferric hydroxide (GFH), an adsorbent developed specifically for the selective removal of arsenic from water. Previous studies have documented the efficiency and high treatment capacity of this approach. We present a novel X-ray fluorescence method to monitor the accumulation of arsenic within a specially designed GFH column, as both a function of time (or water volume) and location along the column. Using a miniature X-ray tube and silicon PiN diode detector, X-ray fluorescence is used to detect characteristic X-rays of arsenic excited from within the GFH. Trials were performed using a water flow rate of approximately 1.5 litres per hour, with an added arsenic concentration of approximately 1000 μg per litre. In this paper, trial results are presented and potential applications described. Characteristic arsenic Kα X-ray peak area as a function of time, as measured at various locations along a granular ferric hydroxide (GFH) water filtration column

Dehydration-rehydration behaviour of zirconium hydroxide and aluminium hydroxide coprecipitated hydrogel

International Nuclear Information System (INIS)

Mitra, N.K.; Guha, P.; Basumajumdar, A.

1989-01-01

Equilibrium dehydration loss experiments on zirconium and aluminium hydroxide coprecipitated hyrogels were carried out up to 600deg and the above heat treated samples were subjected to rehydration at various humidities in order to study the structural flexibilties of the above hydrogel with respect to orientation of water molecules. (author). 6 refs., 3 tabs

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

Synthesis, characterization and application of two-dimensional layered metal hydroxides for environmental remediation purposes

Science.gov (United States)

Machingauta, Cleopas

Two-dimensional layered nano composites, which include layered double hydroxides (LDHs), hydroxy double salts (HDSs) and layered hydroxide salts (LHSs) are able to intercalate different molecular species within their gallery space. These materials have a tunable structural composition which has made them applicable as fire retardants, adsorbents, catalysts, catalyst support materials, and ion exchangers. Thermal treatment of these materials results in destruction of the layers and formation of mixed metal oxides (MMOs) and spinels. MMOs have the ability to adsorb anions from solution and may also regenerate layered structures through a phenomenon known as memory effect. Zinc-nickel hydroxy nitrate was used for the uptake of a series of halogenated acetates (HAs). HAs are pollutants introduced into water systems as by-products of water chlorination and pesticide degradation; their sequestration from water is thus crucial. Optimization of layered materials for controlled uptake requires an understanding of their ion-exchange kinetics and thermodynamics. Exchange kinetics of these anions was monitored using ex-situ PXRD, UV-vis, HPLC and FTIR. It was revealed that exchange rates and uptake efficiencies are related to electronic spatial extents and the charge on carboxyl-oxygen atoms. In addition, acetate and nitrate-based HDSs were used to explore how altering the hydroxide layer affects uptake of acetate/nitrate ions. Changing the metal identities affects the interaction of the anions with the layers. From FTIR, we observed that nitrates coordinate in a D3h and Cs/C 2v symmetry; the nitrates in D3h symmetry were easily exchangeable. Interlayer hydrogen bonding was also revealed to be dependent on metal identity. Substituting divalent cations with trivalent cations produces materials with a higher charge density than HDSs and LHSs. A comparison of the uptake efficiency of zinc-aluminum, zinc-gallium and zinc-nickel hydroxy nitrates was performed using trichloroacetic

Nanoparticles for cultural heritage conservation: calcium and barium hydroxide nanoparticles for wall painting consolidation.

Science.gov (United States)

Giorgi, Rodorico; Ambrosi, Moira; Toccafondi, Nicola; Baglioni, Piero

2010-08-16

Nanotechnology provides new concepts and materials for the consolidation and protection of wall paintings. In particular, humble calcium and barium hydroxide nanoparticles offer a versatile and highly efficient tool to combat the main degradation processes altering wall paintings. Clear example of the efficacy and potentiality of nanotechnology is represented by the conservation in situ of Maya wall paintings in the archaeological area in Calakmul (Mexico).

Calcium hydroxide silylation reaction with trimethylchlorosilane

Directory of Open Access Journals (Sweden)

Novoselnov Anatoliy A.

2016-01-01

Full Text Available The silylation reaction of a calcium hydroxide with a trimethylchlorosilane is studied as a silylation model by the gas-liquid chromatography. The silylation process is divided into three stages. A material balance of these stages is calculated. The schemes of the reactions at each stage of the process are proposed. The modified calcium hydroxide obtained at three repetitive stages of the silylation reaction has been investigated by the x-ray phase analysis, IR spectroscopy, thermal analysis, electron microscopy in a combination with the elemental analysis. It has been determined that at the first stage of the interaction the processes of the trimethylchlorosilane hydrolysis and of the hydrolysis products condensation dominate, and at the same time an adsorption process of the trimethylchlorosilane and its derivatives starts. Further, the hydrolysis of the trimethylchlorosilane by the «new» portions of a water formed in the reaction of a calcium hydroxide with a hydrogen chloride takes place, simultaneously the secondary reactions of the Si-O-Ca – ties’ formation and cleavage occur including as a silylation-desilylation dynamic equilibrium process.

Enterocin P Causes Potassium Ion Efflux from Enterococcus faecium T136 Cells

Science.gov (United States)

Herranz, Carmen; Cintas, Luis M.; Hernández, Pablo E.; Moll, Gert N.; Driessen, Arnold J. M.

2001-01-01

Enterocin P is a bacteriocin produced by Enterococcus faecium P13. We studied the mechanism of its bactericidal action using enterocin-P-sensitive E. faecium T136 cells. The bacteriocin is incapable of dissipating the transmembrane pH gradient. On the other hand, depending on the buffer used, enterocin P dissipates the transmembrane potential. Enterocin P efficiently elicits efflux of potassium ions, but not of intracellularly accumulated anions like phosphate and glutamate. Taken together, these data demonstrate that enterocin P forms specific, potassium ion-conducting pores in the cytoplasmic membrane of target cells. PMID:11181377

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.

Facile synthesis of deoxycholate intercalated layered double hydroxide nanohybrids via a coassembly process

International Nuclear Information System (INIS)

Wu, Xiaowen; Wang, Shuang; Du, Na; Zhang, Renjie; Hou, Wanguo

2013-01-01

In this paper, we describe a synthesis strategy of deoxycholate (DC) intercalated layered double hydroxide (LDH) nanohybrids via a coassembly method at room temperature. For this strategy, LDH particles were delaminated to well-dispersed 2D nanosheets in formamide, and the resulting LDH nanosheets were then coassembled with DC anions into the DC intercalated LDH (DC-LDH) nanohybrids. The so-synthesized nanohybrids were characterized by XRD, TEM, FT-IR, elemental analyses and TG-DSC. It was found that the loading amount of DC in the nanohybrids could be easily controlled by changing the ratio of DC to LDH. In addition, the nanohybrids have similar characteristics with the DC-LDH nanohybrids synthesized by the hydrothermal method, including their DC loading, crystal structure, morphology and thermal gravimetric behavior. However, this strategy exhibited the advantages of short reaction time and mild experimental conditions compared with the hydrothermal method. - Graphical abstract: Deoxycholate intercalated layered double hydroxide nanohybrids were successfully synthesized via a coassembly strategy. In this strategy, the interlayer spaces of LDHs can be efficiently used for the intercalation of guest species. - Highlights: • Deoxycholate intercalated layered double hydroxide nanohybrids were synthesized via a coassembly strategy. • This strategy exhibited the advantages of short time and mild conditions. • This strategy can enable organic species to be readily intercalated into the LDH galleries

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...

Deactivation of nickel hydroxide-gold modified electrodes

OpenAIRE

Caram, Bruno; Tucceri, Ricardo

2013-01-01

The aim of the present work was to study how the charge-transport process of a nickel hydroxide film electrochemically synthesized on a gold substrate is modified when the electrode is stored for a long time. It was found that nickel hydroxide films are deactivated under storage, that is, films became less conductive than films immediately prepared (nondeactivated). This study was carried out in the context of the rotating disc electrode voltammetry when the modified electrode contacts an ele...

Neutralization of Hydroxide Ion in Melt-Grown NaCl Crystals

Science.gov (United States)

Otterson, Dumas A.

1961-01-01

Many recent studies of solid-state phenomena, particularly in the area of crystal imperfections, have involved the use of melt-grown NaCl single crystals. Quite often trace impurities in these materials have had a prominent effect on these phenomena. Trace amounts of hydroxide ion have been found in melt-grown NaCl crystals. This paper describes a nondestructive method of neutralizing the hydroxide ion in such crystals. Crystals of similar hydroxide content are maintained at an elevated temperature below the melting point of NaCl in a flowing atmosphere containing. dry hydrogen chloride. Heat treatment is continued until an analysis of the test specimens shows no excess hydroxide ion. A colorimetric method previously described4 is used for this analysis.

Luminescent materials based on Tb, Eu-containing layered double hydroxides

International Nuclear Information System (INIS)

Zhuravleva, N.G.; Eliseev, A.A.; Lukashin, A.V.; Kinast, U.; Tret'yakov, Yu.D.

2004-01-01

Luminescent materials on the basis of magnesium-aluminium layered double hydroxides with intercalated anionic complexes of terbium and europium picolinates were synthesized. Relying on data of spectroscopy, elementary and X-ray phase analyses, the change in the rare earth complex structure and metal/ligand ratio, depending on the hydroxide layer charge, determined by Mg/Al ratio in the double hydroxide, were ascertained. The values of quantum yields of luminescence for terbium-containing samples amounted to 30-50% [ru

Kinetic behaviour of the adsorption and desorption of phosphorus-32 on aluminium hydroxide

International Nuclear Information System (INIS)

Ribeiro, E.M.G.

1993-01-01

Great amount of phosphate fertilizers are used in agriculture. Soil fertility have been studied using fertilizer labelled with phosphorus 32 to improve agronomic practices by increasing the efficient use of phosphate fertilizer. Previous research work have been published suggesting the potential use of kinetics parameters to characterize phosphorus in soil and to diagnosis the phosphate level. In this work the kinetic behaviour of the absorption and desorption of phosphorus-32 on a synthetic aluminium hydroxide was studied attempting to detect the formation of a precipitated phase on the hydroxide surface. The kinetic data for adsorption was adjusted with the Elovich and Fardeau equations for isotopic exchange. It was verified a change in the kinetic behaviour when the surface was approximately 80% saturated. This change suggested the formation of a precipitate. The kinetic data for desorption was fitted with the Fardeau equation, and it was verified the desorption kinetics slower than the desorption. (B.C.A.). 40 refs, 17 figs, 5 tabs

Thermochemical properties of the alkali hydroxides: A review

International Nuclear Information System (INIS)

Konings, R.J.M.; Cordfunke, E.H.P.

1989-01-01

The formation of volatile alkali hydroxides as a result of high-temperature steam corrosion plays an important role in nuclear technology. For the modeling of the volatilization processes, reliable thermodynamic data are required. In the present paper recent physico-chemical experiments by the authors will be discussed and the thermochemical properties of the alkali hydroxide series will be evaluated. (orig.)

Operating experience with potassium systems

International Nuclear Information System (INIS)

Schwarz, N.F.

1984-04-01

In an international cooperation R and D work for the realization of potassium topping cycles to increase the conversion efficiency of thermal power stations is going on. Feasibility studies show that the realization of such a process can be achieved under economic considerations with existing materials and today's technology. Nevertheless, it has to be shown that the assumptions with respect to material behaviour and component reliability are based on sound technical premises. Therefore, in continuation of design studies, a hardware programme has been initiated in the Austrian Research Centre Seibersdorf. First results with respect to component and material behaviour are described. (Author) [de

Average formation number n-barOH of colloid-type indium hydroxide

International Nuclear Information System (INIS)

Stefanowicz, T.; Szent-Kirallyine Gajda, J.

1983-01-01

Indium perchlorate in perchloric acid solution was titrated with sodium hydroxide solution to various pH values. Indium hydroxide colloid was removed by ultracentrifugation and supernatant solution was titrated with base to neutral pH. The two-stage titration data were used to calculate the formation number of indium hydroxide colloid, which was found to equal n-bar OH = 2.8. (author)

DOUBLE-SHELL TANK (DST) HYDROXIDE DEPLETION MODEL FOR CARBON DIOXIDE ABSORPTION

International Nuclear Information System (INIS)

OGDEN DM; KIRCH NW

2007-01-01

This document generates a supernatant hydroxide ion depletion model based on mechanistic principles. The carbon dioxide absorption mechanistic model is developed in this report. The report also benchmarks the model against historical tank supernatant hydroxide data and vapor space carbon dioxide data. A comparison of the newly generated mechanistic model with previously applied empirical hydroxide depletion equations is also performed

Determination of technetium-99 from complex matrix

International Nuclear Information System (INIS)

Lixiong Wang; Lei Tang; Tongzai Yang; Yanqiu Yang; Liang Yang

2013-01-01

This paper reports an approach that can be used for efficient separation and determination of 99 Tc (as pertechnetate) after contamination of the environment by nuclear materials. The samples were decomposed by fusion in a mixture of potassium hydroxide and potassium nitrate. After fusion, technetium remains as the pertechnetate anion (TcO 4 - ). The technetium was isolated from the sample by technique combining solvent extraction, anion exchange, then, again, solvent extraction. After separation, 99 Tc was measured by isotope-dilution mass spectrometry with 97 Tc as spike. This method yielded nanogram detection limits for 99 Tc. (author)

Free energy dissipation of the spontaneous gating of a single voltage-gated potassium channel.

Science.gov (United States)

Wang, Jia-Zeng; Wang, Rui-Zhen

2018-02-01

Potassium channels mainly contribute to the resting potential and re-polarizations, with the potassium electrochemical gradient being maintained by the pump Na + /K + -ATPase. In this paper, we construct a stochastic model mimicking the kinetics of a potassium channel, which integrates temporal evolving of the membrane voltage and the spontaneous gating of the channel. Its stationary probability density functions (PDFs) are found to be singular at the boundaries, which result from the fact that the evolving rates of voltage are greater than the gating rates of the channel. We apply PDFs to calculate the power dissipations of the potassium current, the leakage, and the gating currents. On a physical perspective, the essential role of the system is the K + -battery charging the leakage (L-)battery. A part of power will inevitably be dissipated among the process. So, the efficiency of energy transference is calculated.

Free energy dissipation of the spontaneous gating of a single voltage-gated potassium channel

Science.gov (United States)

Wang, Jia-Zeng; Wang, Rui-Zhen

2018-02-01

Potassium channels mainly contribute to the resting potential and re-polarizations, with the potassium electrochemical gradient being maintained by the pump Na+/K+-ATPase. In this paper, we construct a stochastic model mimicking the kinetics of a potassium channel, which integrates temporal evolving of the membrane voltage and the spontaneous gating of the channel. Its stationary probability density functions (PDFs) are found to be singular at the boundaries, which result from the fact that the evolving rates of voltage are greater than the gating rates of the channel. We apply PDFs to calculate the power dissipations of the potassium current, the leakage, and the gating currents. On a physical perspective, the essential role of the system is the K+-battery charging the leakage (L-)battery. A part of power will inevitably be dissipated among the process. So, the efficiency of energy transference is calculated.

Chemical deacetylation natural xanthan (Jungbunzlauer®

Directory of Open Access Journals (Sweden)

Ellen P. Pinto

2011-01-01

Full Text Available With the aim of adapting a method for removal of acetyl groups from xanthan, reactions of chemical deacetylation were carried out with natural xanthan (Jungbunzlauer® with variations on the following parameters: biopolymer and alkali concentration (sodium and potassium hydroxide. The deacetylation reaction was performed at 25 ºC for three hours. The proposed methodology was efficient to promote the deacetylation reaction. The viscosity of xanthan increased when the alkali concentration was higher in the deacetylation reaction. Xanthan concentration in the solution used in the deacetylation reaction did not influence the solutions viscosity, as similar results in both tested biopolymer concentrations (0.5 and 1% were obtained for all experiments in different shear rates. Deacetylation reactions at 25 ºC for three hours with sodium and potassium hydroxide in 0.01 mol.L-1 showed a viscosity of 410 and 420 mPa.s at 10 s-1 and acetylation degree 1.3 e 1.4%, respectively.

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

Synthesis, characterization and stability of Cr(III) and Fe(III) hydroxides

International Nuclear Information System (INIS)

Papassiopi, N.; Vaxevanidou, K.; Christou, C.; Karagianni, E.; Antipas, G.S.E.

2014-01-01

Highlights: • Fe(III)–Cr(III) hydroxides enhance groundwater quality better than pure Cr(III) compounds. • Crystalline Cr(OH) 3 ·3H 2 O was unstable, with a solubility higher than 50 μg/l. • Amorphous Cr(OH) 3 (am) was stable with a solubility lower than 50 μg/l in the range 5.7 0.75 Cr 0.25 (OH) 3 , the stability region was extended to 4.8 3 ·xH 2 O whereas in the presence of iron the precipitate is a mixed Fe (1−x) Cr x (OH) 3 phase. In this study, we report on the synthesis, characterisation and stability of mixed (Fe x ,Cr 1−x )(OH) 3 hydroxides as compared to the stability of Cr(OH) 3 . We established that the plain Cr(III) hydroxide, abiding to the approximate molecular formula Cr(OH) 3 ·3H 2 O, was crystalline, highly soluble, i.e. unstable, with a tendency to transform into the stable amorphous hydroxide Cr(OH) 3 (am) phase. Mixed Fe 0.75 Cr 0.25 (OH) 3 hydroxides were found to be of the ferrihydrite structure, Fe(OH) 3 , and we correlated their solubility to that of a solid solution formed by plain ferrihydrite and the amorphous Cr(III) hydroxide. Both our experimental results and thermodynamic calculations indicated that mixed Fe(III)–Cr(III) hydroxides are more effective enhancers of groundwater quality, in comparison to the plain amorphous or crystalline Cr(III) hydroxides, the latter found to have a solubility typically higher than 50 μg/l (maximum EU permitted Cr level in drinking water), while the amorphous Cr(OH) 3 (am) phase was within the drinking water threshold in the range 5.7 0.75 Cr 0.25 (OH) 3 hydroxides studied were of extended stability in the 4.8 < pH < 13.5 range

Layered-Double-Hydroxide Nanosheets as Efficient Visible-Light-Driven Photocatalysts for Dinitrogen Fixation.

Science.gov (United States)

Zhao, Yufei; Zhao, Yunxuan; Waterhouse, Geoffrey I N; Zheng, Lirong; Cao, Xingzong; Teng, Fei; Wu, Li-Zhu; Tung, Chen-Ho; O'Hare, Dermot; Zhang, Tierui

2017-11-01

Semiconductor photocatalysis attracts widespread interest in water splitting, CO 2 reduction, and N 2 fixation. N 2 reduction to NH 3 is essential to the chemical industry and to the Earth's nitrogen cycle. Industrially, NH 3 is synthesized by the Haber-Bosch process under extreme conditions (400-500 °C, 200-250 bar), stimulating research into the development of sustainable technologies for NH 3 production. Herein, this study demonstrates that ultrathin layered-double-hydroxide (LDH) photocatalysts, in particular CuCr-LDH nanosheets, possess remarkable photocatalytic activity for the photoreduction of N 2 to NH 3 in water at 25 °C under visible-light irradiation. The excellent activity can be attributed to the severely distorted structure and compressive strain in the LDH nanosheets, which significantly enhances N 2 chemisorption and thereby promotes NH 3 formation. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

HYDROGEN PEROXIDE BLEACHING OF CMP PULP USING MAGNESIUM HYDROXIDE

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Farhad Zeinaly

2009-11-01

Full Text Available Conventional bleaching of hardwood CMP pulp with magnesium hydroxide (Mg(OH2 show significant benefits over bleaching with sodium hydroxide (NaOH under various conditions. Magnesium hydroxide bleaching generate higher optical properties, higher pulp yield and lower effluent COD at the same chemical charge, but the physical properties were found to be similar for both processes. The initial freeness of the bleached pulps and refining value to reach a target freeness (about 350 ml. CSF were more for the Mg(OH2-based process. The residual peroxide of filtrate from the Mg(OH2-based process was very high as compared to conventional bleaching.

Fly ash/Kaolin based geopolymer green concretes and their mechanical properties

Directory of Open Access Journals (Sweden)

F.N. Okoye

2015-12-01

Full Text Available Geopolymer concrete mixes were cast using fly ash, kaolin, sodium hydroxide, potassium hydroxide, sodium silicate and aggregates. Portland cement concrete (M30 was used as a reference sample. The effect of silica fume, temperature (40 °C, 60 °C, 80 °C, 100 °C and 120 °C, sodium and potassium hydroxides and different superplasticizers on the compressive strength are reported [1]. Maximum strength was found at 100 °C and 14 M alkali solution [1].

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.

Effects of potassium application on the accumulated nitrogen source and yield of peanut

International Nuclear Information System (INIS)

Wang Yuefu; Kang Yujie; Wang Minglun; Zhao Changxing

2013-01-01

Pot experiments and were carried out respectively to study the effects of different potassium application on soil nitrogen uptake, fertilizer nitrogen uptake, nodule nitrogen fixation and their proportion and yield of peanut (Arachis Hypogaea L.) by "1"5N tracer technique, and explore the reasons, which may provide a theoretical basis and technical guidance for peanut production in the scientific fertilizer application. Results showed that nitrogen in peanut all mainly accumulated in the kernel for different treatments of potassium fertilizer application. However, with increasing of potassium application, the increasing extent of nitrogen content of stems was the biggest during all the peanut organs, with nut shells the smallest. Properly increasing the amount of potassium can improve nitrogen content, "1"5N abundance, nitrogen and "1"5N accumulation of every organ, and promote absorption and utilization three nitrogen-source especially with the most effect for the kernel biomass (economic output). The ratio of fertilizer nitrogen, soil nitrogen and atmospheric nitrogen absorbed by peanut was respectively between 12.37%-13.10%, 38.29%-45.10%, and 42.53%-48.31% respectively. Properly increasing potassium fertilizer application improved the absorption ratio of fertilizer nitrogen and nodule nitrogen fixation, reduced the proportion of soil uptake and enhanced fertilizer nitrogen use efficiency. However, the influences of excessive application of potassium fertilizer decreased. (authors)

Effect of soaking of seeds in potassium silicate and uniconazole on ...

African Journals Online (AJOL)

... by low concentration of uniconazole treatment as compared to the control and other treatments. The growth of tomato seedlings was efficiently regulated by uniconazole 50 mg L-1 (12 h soaking) treatment. Key words: Chlorophyll fluorescence, plant growth retardants, plug plants, potassium silicate, seed treatment, silicon, ...

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....

Ion-exchange synthesis of compounds based on low-water niobium hydroxide

International Nuclear Information System (INIS)

Ivanova, N.E.; Sakharov, V.E.; Korovin, S.S.

1977-01-01

Ordinary physico-chemical methods have been used for studying the possibilities of the ion-exchange synthesis of niobates of alkaline and alkaline-earth elements based on low-water niobium hydroxide small at relatively low temperatures. It has been established that cation-exchange properties of low-water niobium hydroxide are revealed in a wide range of pH (from 8.95 to 12.4 for alkaline-earth elements and from 6.7 to 12.0 for alkaline elements). Physico-chemical study of solid phases points that there is a monophase with low-water niobium hydroxide. The rate of crystallization ageing of amorphous phases based on low-water niobium hydroxide is rather small for the samples with a M:Nb ratio less than 1.0 whereas mixed hydroxides with M:Nb ratio more than 1.0 reveal on X-ray diffraction patterns diffusion reflections after keeping in mother liquor for 5 hours-1 day

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 ...

The citotoxicity of calcium hydroxide intracanal dressing by MTT assay

Directory of Open Access Journals (Sweden)

Nanik Zubaidah

2007-12-01

Full Text Available Calcium hydroxide had been used as the intracanal dressing in endodontic treatment due to its high alkaline and high antimicrobial capacity. It also be able to dissolve the necrotic tissue, prevent the root resorbtion and regenerate a new hard tissue. The aim of this study is to identify the concentration of calcium hydroxide that has the lowest citotoxicity. There are 5 groups, each group had 8 samples with different concentration of calcium hydroxide. Group I: 50%, Group II: 55%, Group III: 60%, Group IV: 65% and Group V: 70%. The citotoxicity test by using enzymatic assay of MTT [3-(4.5- dimethylthiazol-2yl ]-2.5 diphenyl tetrazolium bromide, against fibroblast cell (BHK-21. The result of susceptibility test was showed by the citotoxicity detection of the survive cell of fibroblast that was measured spectrophotometrically using 595 nm beam. The data was analyzed using One-Way ANOVA test with significant difference α = 0.05 and subsequently LSD test. The result showed that in concentration 50%, 55%, 60%, 65%, and 70% calcium hydroxide had low toxicity, but calcium hydroxide 60%, had the lowest toxicity.

Direct determination of calcium, sodium and potassium in fermented milk products

Directory of Open Access Journals (Sweden)

Kravić Snežana Ž.

2012-01-01

Full Text Available The aim of this study was the investigation of the possibilities of direct determination of calcium, sodium and potassium in the commercial and kombucha-based fermented milk products by flame photometry. Two procedures were used for sample preparation: simple dilution with water (direct method and extraction with mineral acid. Calcium, sodium and potassium levels determined after mentioned sample preparation methods were compared. The results showed that the differences between the values obtained for the different sample treatment were within the experimental error at the 95% confidence level. Compared to the method based on extraction with mineral acid, the direct method is efficient, faster, simpler, cheaper, and operates according to the principles of Green Chemistry. Consequently, the proposed method for the direct determination of calcium, sodium and potassium could be applied for the rapid routine analysis of the mineral content in the fermented dairy products. [Projekat Ministarstva nauke Republike Srbije, br. III 46009

Sorption of chromium(VI) and chromium(III) on aluminium hydroxide

International Nuclear Information System (INIS)

Music, S.

1986-01-01

Factors that influence the sorption of Cr(VI) and Cr(III) on aluminium hydroxide were investigated. The sorption of chromates decreases as the pH of the suspension increases. The mechanism of CrOsub(4)sup(2-) sorption was interpreted in terms of reactions between chromates and -OH and/or Hsub(2)O groups at the hydroxide/liquid interface. It was shown that chromates are more tightly sorbed on aluminium hydroxide compared to other anions, e.g. chlorides. On the other hand, specifically absorbed anions, such as molybdates, compete strongly with chromates for the sorption sites. The sorption of chromium(III) increases with the pH of the suspension. Also, the sorption of chromium(III) is suppressed in the presence of citrate ions. The best conditions for the fixation of Cr(VI) and Cr(III) by aluminium hydroxide are presented. (author)

Flexural Properties of Activated Carbon Filled Epoxy Nano composites

International Nuclear Information System (INIS)

Khalil, H.P.S.A.; Khalil, H.P.S.A.; Alothman, O.Y.; Paridah, M.T.; Zainudin, E.S.

2014-01-01

Activated carbon (AC) filled epoxy nano composites obtained by mixing the desired amount of nano AC viz., bamboo stem, oil palm empty fruit bunch, and coconut shell from agricultural biomass with the epoxy resin. Flexural properties of activated carbons filled epoxy nano composites with 1 %, and 5 % filler loading were measured. In terms of flexural strength and modulus, a significant increment was observed with addition of 1 % vol and 5 % vol nano-activated carbon as compared to neat epoxy. The effect of activated carbon treated by two chemical agents (potassium hydroxide and phosphoric acid) on the flexural properties of epoxy nano composites were also investigated. Flexural strength of activated carbon-bamboo stem, activated carbon-oil palm, and activated carbon-coconut shell reinforced epoxy nano composites showed almost same value in case of 5 % potassium hydroxide activated carbon. Flexural strength of potassium hydroxide activated carbon-based epoxy nano composites was higher than phosphoric acid activated carbon. The flexural toughness of both the potassium hydroxide and phosphoric acid activated carbon reinforced composites range between 0.79 - 0.92 J. It attributed that developed activated carbon filled epoxy nano composites can be used in different applications. (author)

Dry cell battery poisoning

Science.gov (United States)

Batteries - dry cell ... Acidic dry cell batteries contain: Manganese dioxide Ammonium chloride Alkaline dry cell batteries contain: Sodium hydroxide Potassium hydroxide Lithium dioxide dry cell batteries ...

Crystallite size effects in stacking faulted nickel hydroxide and its electrochemical behaviour

International Nuclear Information System (INIS)

Ramesh, T.N.

2009-01-01

β-Nickel hydroxide comprises a long range periodic arrangement of atoms with a stacking sequence of AC AC AC-having an ideal composition Ni(OH) 2 . Variation in the preparative conditions can lead to the changes in the stacking sequence (AC AC BA CB AC AC or AC AC AB AC AC). This type of variation in stacking sequence can result in the formation of stacking fault in nickel hydroxide. The stability of the stacking fault depends on the free energy content of the sample. Stacking faults in nickel hydroxide is essential for better electrochemical activity. Also there are reports correlating particle size to the better electrochemical activity. Here we present the effect of crystallite size on the stacking faulted nickel hydroxide samples. The electrochemical performance of stacking faulted nickel hydroxide with small crystallite size exchanges 0.8e/Ni, while the samples with larger crystallite size exchange 0.4e/Ni. Hence a right combination of crystallite size and stacking fault content has to be controlled for good electrochemical activity of nickel hydroxide

Synthesis of hydroxide type sorbents from industry high-iron wastes

International Nuclear Information System (INIS)

Stepanenko, E.K.; Smirnov, A.L.

1986-01-01

Article presents the results of studies on possibility of using of technological iron containing wastes for the obtaining of hydroxide type sorbents in granular form. The scheme of technology of synthesis of hydroxide type sorbents from high-iron wastes is elaborated.

Hydroxide catalysts for lignin depolymerization

Science.gov (United States)

Beckham, Gregg T; Biddy, Mary J.; Kruger, Jacob S.; Chmely, Stephen C.; Sturgeon, Matthew

2017-10-17

Solid base catalysts and their use for the base-catalyzed depolymerization (BCD) of lignin to compounds such as aromatics are presented herein. Exemplary catalysts include layered double hydroxides (LDHs) as recyclable, heterogeneous catalysts for BCD of lignin.

Hydroxide catalysts for lignin depolymerization

Energy Technology Data Exchange (ETDEWEB)

Beckham, Gregg T.; Biddy, Mary J.; Chmely, Stephen C.; Sturgeon, Matthew

2017-04-25

Solid base catalysts and their use for the base-catalyzed depolymerization (BCD) of lignin to compounds such as aromatics are presented herein. Exemplary catalysts include layered double hydroxides (LDHs) as recyclable, heterogeneous catalysts for BCD of lignin.

Visible-light-enhanced interactions of hydrogen sulfide with composites of zinc (oxy)hydroxide with graphite oxide and graphene.

Science.gov (United States)

Seredych, Mykola; Mabayoje, Oluwaniyi; Bandosz, Teresa J

2012-01-17

Composites of zinc(oxy)hydroxide-graphite oxide and of zinc(oxy)hydroxide-graphene were used as adsorbents of hydrogen sulfide under ambient conditions. The initial and exhausted samples were characterized by XRD, FTIR, potentiometric titration, EDX, thermal analysis, and nitrogen adsorption. An increase in the amount of H(2)S adsorbed/oxidized on their surfaces in comparison with that of pure Zn(OH)(2) is linked to the structure of the composite, the relative number of terminal hydroxyls, and the kind of graphene-based phase used. Although terminal groups are activated by a photochemical process, the graphite oxide component owing to the chemical bonds with the zinc(oxy)hydroxide phase and conductive properties helps in electron transfer, leading to more efficient oxygen activation via the formation of superoxide ions. Elemental sulfur, zinc sulfide, sulfite, and sulfate are formed on the surface. The formation of sulfur compounds on the surface of zinc(oxy)hydroxide during the course of the breakthrough experiments and thus Zn(OH)(2)-ZnS heterojunctions can also contribute to the increased surface activity of our materials. The results show the superiority of graphite oxide in the formation of composites owing to its active surface chemistry and the possibility of interface bond formation, leading to an increase in the number of electron-transfer reactions. © 2011 American Chemical Society

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

Potassium iodide stockpiling

International Nuclear Information System (INIS)

Krimm, R.W.

1983-01-01

After examination by the Federal Emergency Management Agency (FEMA) and other federal agencies of federal policy on the use and distribution of potassium iodide (KI) as a thyroid-blocking agent for use in off-site preparedness around commercial nuclear powerplants, FEMA believes the present shelf life of KI is too short, that the minimum ordering quantities are an obstacle to efficient procurement, and that the packaging format offered by the drug industry does not meet the wishes of state and local government officials. FEMA has asked assistance from the Food and Drug Administration in making it possible for those states wishing to satisfy appropriate requirements to do so at the minimum cost to the public. Given an appropriate packaging and drug form, there appears to be no reason for the federal government to have further involvement in the stockpiling of KI

Commercial expanded graphite as a low-cost, long-cycling life anode for potassium-ion batteries with conventional carbonate electrolyte

Science.gov (United States)

An, Yongling; Fei, Huifang; Zeng, Guifang; Ci, Lijie; Xi, Baojuan; Xiong, Shenglin; Feng, Jinkui

2018-02-01

Design and synthesis of capable anode materials that can store the large size K+ is the key of development for potassium-ion batteries. The low-cost and commercial expanded graphite with large particles is a graphite-derived material with good conductivity and enlarged interlayer spaces to boost the potassium ion diffusion coefficient during charge/discharge process. Thus, we achieve excellent anode performance for potassium-ion batteries based on an expanded graphite. It can deliver a capacity of 263 mAh g-1 at the rate of 10 mA g-1 and the reversible capacity remains almost unchanged after 500 cycles at a high rate of 200 mA g-1 with a coulombic efficiency of around 100%. The potassium storage mechanism is investigated by the ex situ XRD technique. This excellent potassium storage performance will make the expanded graphite promising anode candidate for potassium ion batteries.

Layered-metal-hydroxide nanosheet arrays with controlled nanostructures to assist direct electronic communication at biointerfaces.

Science.gov (United States)

An, Zhe; Lu, Shan; Zhao, Liwei; He, Jing

2011-10-18

In this work, ordered vertical arrays of layered double hydroxide (LDH) nanosheets have been developed to achieve electron transfer (eT) at biointerfaces in electrochemical devices. It is found that tailoring the gap size of LDH nanosheet arrays could significantly promote the eT rate. This research has successfully extended nanomaterials for efficient modifications of electrode surfaces from nanoparticles, nanowires, nanorods, and nanotubes to nanosheets. © 2011 American Chemical Society

Effects of potassium behaviour in soils on crop absorption | Lin ...

African Journals Online (AJOL)

Potassium (K) is one of the three major elements that play important roles in plants, such as maintaining turgor of cells, promoting activation of enzymes, and improving efficiency of photosynthesis. The types of K in soil may affect the plant absorption of K. K in soils includes K minerals, K in layered silicates (clay minerals), ...

Co-precipitation and solubility studies of cesium, potassium and sodium tetraphenylborate

International Nuclear Information System (INIS)

Peterson, R.A.

1999-01-01

This report contains the results from a study requested by High Level Waste Division on the co-precipitation and solubility of cesium, potassium, and sodium tetraphenylborate. Co-precipitation of cesium (Cs), potassium (K), and sodium (Na) tetraphenylborate (TPB) helps determine the efficiency of reagent usage in the Small Tank Precipitation Process. This process uses NaTPB to remove cesium from waste by means of precipitation. Previous studies by McCabe suggested that if the sodium ion concentration [Na+] increased the rate at which cesium tetraphenylborate (KTPB) in the presence of high [Na+] (∼5M) appears to produce a mixed solid phase composed of NaTPB and KTPB together in the crystal lattice

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.

Synthesis of aluminum oxy-hydroxide nanofibers from porous anodic alumina

Energy Technology Data Exchange (ETDEWEB)

Jha, Himendra; Kikuchi, Tatsuya; Sakairi, Masatoshi; Takahashi, Hideaki [Laboratory of Interface Microstructure Analysis (LIMSA), Division of Materials Science and Engineering, Graduate School of Engineering, Hokkaido University, Sapporo 060-8628 (Japan)], E-mail: himendra@eng.hokudai.ac.jp

2008-10-01

A novel method for the synthesis of aluminum oxy-hydroxide nanofibers from a porous anodic oxide film of aluminum is demonstrated. In the present method, the porous anodic alumina not only acts as a template, but also serves as the starting material for the synthesis. The porous anodic alumina film is hydrothermally treated for pore-sealing, which forms aluminum oxy-hydroxide inside the pores of the oxide film as well as on the surface of the film. The hydrothermally sealed porous oxide film is immersed in the sodium citrate solution, which selectively etches the porous aluminum oxide from the film, leaving the oxy-hydroxide intact. The method is simple and gives highly uniform aluminum oxy-hydroxide nanofibers. Moreover, the diameter of the nanofibers can be controlled by controlling the pore size of the porous anodic alumina film, which depends on the anodizing conditions. Nanofibers with diameters of about 38-85 nm, having uniform shape and size, were successfully synthesized using the present method.

Synthesis of aluminum oxy-hydroxide nanofibers from porous anodic alumina

International Nuclear Information System (INIS)

Jha, Himendra; Kikuchi, Tatsuya; Sakairi, Masatoshi; Takahashi, Hideaki

2008-01-01

A novel method for the synthesis of aluminum oxy-hydroxide nanofibers from a porous anodic oxide film of aluminum is demonstrated. In the present method, the porous anodic alumina not only acts as a template, but also serves as the starting material for the synthesis. The porous anodic alumina film is hydrothermally treated for pore-sealing, which forms aluminum oxy-hydroxide inside the pores of the oxide film as well as on the surface of the film. The hydrothermally sealed porous oxide film is immersed in the sodium citrate solution, which selectively etches the porous aluminum oxide from the film, leaving the oxy-hydroxide intact. The method is simple and gives highly uniform aluminum oxy-hydroxide nanofibers. Moreover, the diameter of the nanofibers can be controlled by controlling the pore size of the porous anodic alumina film, which depends on the anodizing conditions. Nanofibers with diameters of about 38-85 nm, having uniform shape and size, were successfully synthesized using the present method

Layered Double Hydroxides as Effective Adsorbents for U(VI and Toxic Heavy Metals Removal from Aqueous Media

Directory of Open Access Journals (Sweden)

G. N. Pshinko

2013-01-01

Full Text Available Capacities of different synthesized Zn,Al-hydrotalcite-like adsorbents, including the initial carbonate [Zn4Al2(OH12]·CO3·8H2O and its forms intercalated with chelating agents (ethylenediaminetetraacetic acid (EDTA, diethylenetriaminepentaacetic acid (DTPA, and hexamethylenediaminetetraacetic acid (HMDTA and heat-treated form Zn4Al2O7, to adsorb uranium(VI and ions of toxic heavy metals have been compared. Metal sorption capacities of hydrotalcite-like adsorbents have been shown to correlate with the stability of their complexes with the mentioned chelating agents in a solution. The synthesized layered double hydroxides (LDHs containing chelating agents in the interlayer space are rather efficient for sorption purification of aqueous media free from U(VI irrespective of its forms of natural abundance (including water-soluble bi- and tricarbonate forms and from heavy metal ions. [Zn4Al2(OH12]·EDTA·nH2O is recommended for practical application as one of the most efficient and inexpensive synthetic adsorbents designed for recovery of both cationic and particularly important anionic forms of U(VI and other heavy metals from aqueous media. Carbonate forms of LDHs turned out to be most efficient for recovery of Cu(II from aqueous media with pH0≥7 owing to precipitation of Cu(II basic carbonates and Cu(II hydroxides. Chromate ions are efficiently adsorbed from water only by calcinated forms of LDHs.

Impact of mild alkali dosage on immobilized Exiguobacterium spp. mediated cost and energy efficient sludge disintegration.

Science.gov (United States)

Rajesh Banu, J; Ushani, U; Rajkumar, M; Naresh Kumar, R; Parthiba Karthikeyan, O

2017-12-01

Approaches to (extracellular polymeric substance) EPS removal were studied with major aim to enhance the biodegradability and sludge solubilization. In this study, a novel approach of entrapment of bacterial strain was carried out to achieve long term activity of protease secreting bacteria Exiguobacterium sp. A mild treatment of potassium hydroxide (KOH) was applied to remove EPS which was followed by entrapment under the biological pretreatment. The efficiency of Exiguobacterium was predicted through dissolvable organic and suspended solids (SS) reduction. The maximum dissolvable organic matter released was 2300mg/L with the solubilization of 23% which was obtained for sludge without EPS (SWOE). For dissolvable organic release, SWOE showed higher final methane production of 232mL/g COD at the production rate of 16.2mL/g COD.d. The SWOE pretreatment was found to be cost effective and less energy intensive beneficial in terms of energy and cost (43.9KWh and -8.2USD) when compared to sludge with EPS (SWE) pretreatment (-177.6KWh and -91.23USD). Copyright © 2017 Elsevier Ltd. All rights reserved.

21 CFR 177.1600 - Polyethylene resins, carboxyl modified.

Science.gov (United States)

2010-04-01

... produced when ethylene-methyl acrylate basic copolymers, containing no more than 25 weight percent of polymer units derived from methyl acrylate, are made to react in an aqueous medium with one or more of the following substances: Ammonium hydroxide. Calcium carbonate. Potassium hydroxide. Sodium hydroxide. (b) The...

40 CFR 268.42 - Treatment standards expressed as specified technologies.

Science.gov (United States)

2010-07-01

... such as copper, zinc, nickel, gold, and sulfur that result in a nonliquid, semi-solid amalgam and..., hydroxides, carbonates, sulfides, sulfates, chlorides, flourides, or phosphates. The following reagents (or... hydroxides of calcium and/or magnesium; (2) caustic (i.e., sodium and/or potassium hydroxides; (3) soda ash...

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...

Correction of metabolic acidosis with potassium citrate in renal transplant patients and its effect on bone quality.

Science.gov (United States)

Starke, Astrid; Corsenca, Alf; Kohler, Thomas; Knubben, Johannes; Kraenzlin, Marius; Uebelhart, Daniel; Wüthrich, Rudolf P; von Rechenberg, Brigitte; Müller, Ralph; Ambühl, Patrice M

2012-09-01

Acidosis and transplantation are associated with increased risk of bone disturbances. This study aimed to assess bone morphology and metabolism in acidotic patients with a renal graft, and to ameliorate bone characteristics by restoration of acid/base homeostasis with potassium citrate. This was a 12-month controlled, randomized, interventional trial that included 30 renal transplant patients with metabolic acidosis (S-[HCO(3)(-)] 24 mmol/L, or potassium chloride (control group). Iliac crest bone biopsies and dual-energy X-ray absorptiometry were performed at baseline and after 12 months of treatment. Bone biopsies were analyzed by in vitro micro-computed tomography and histomorphometry, including tetracycline double labeling. Serum biomarkers of bone turnover were measured at baseline and study end. Twenty-three healthy participants with normal kidney function comprised the reference group. Administration of potassium citrate resulted in persisting normalization of S-[HCO(3)(-)] versus potassium chloride. At 12 months, bone surface, connectivity density, cortical thickness, and cortical porosity were better preserved with potassium citrate than with potassium chloride, respectively. Serological biomarkers and bone tetracycline labeling indicate higher bone turnover with potassium citrate versus potassium chloride. In contrast, no relevant changes in bone mineral density were detected by dual-energy X-ray absorptiometry. Treatment with potassium citrate in renal transplant patients is efficient and well tolerated for correction of metabolic acidosis and may be associated with improvement in bone quality. This study is limited by the heterogeneity of the investigated population with regard to age, sex, and transplant vintage.

Biogenic Fe(III) minerals lower the efficiency of iron-mineral based commercial filter systems for arsenic removal

DEFF Research Database (Denmark)

Kleinert, Susanne; Muehe, Eva M.; Posth, Nicole

2011-01-01

Millions of people worldwide are affected by As (arsenic) contaminated groundwater. Fe(III) (oxy)hydroxides sorb As efficiently and are therefore used in water purification filters. Commercial filters containing abiogenic Fe(III) (oxy)hydroxides (GEH) showed varying As removal, and it was unclear...

Cobalt hydroxide nanoflakes and their application as supercapacitors and oxygen evolution catalysts

Science.gov (United States)

Rovetta, A. A. S.; Browne, M. P.; Harvey, A.; Godwin, I. J.; Coleman, J. N.; Lyons, M. E. G.

2017-09-01

Finding alternative routes to access and store energy has become a major issue recently. Transition metal oxides have shown promising behaviour as catalysts and supercapacitors. Recently, liquid exfoliation of bulk metal oxides appears to be an effective route which provides access to two-dimensional (2D) nano-flakes, the size of which can be easily selected. These 2D materials exhibit excellent electrochemical charge storage and catalytic activity for the oxygen evolution reaction. In this study, various sized selected cobalt hydroxide nano-flake materials are fabricated by this time efficient and highly reproducible process. Subsquently, the electrochemical properties of the standard size Co(OH)2 nanoflakes were investigated. The oxide modified electrodes were prepared by spraying the metal oxide flake suspension onto a porous conductive support electrode foam, either glassy carbon or nickel. The cobalt hydroxide/nickel foam system was found to have an overpotential value at 10 mA cm-2 in 1 M NaOH as low as 280 mV and an associated redox capacitance exhibiting numerical values up to 1500 F g-1, thereby making it a viable dual use electrode.

MOLLUSCUM CONTAGIOSUM WITH CHILDREN: PECULIARITIES OF COURSE AND MODERN APPROACHES TO THERAPY

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N. N. Murashkin

2016-01-01

Full Text Available The article deals with the main aspects of the epidemiology and clinical course of molluscum contagiosum with children. Comparative analysis of the effectiveness  of different treatment  methods has been done. Based on the data of multicenter clinical studies, the authors concluded that the high efficiency and good tolerance  of 5% potassium hydroxide solution in the treatment  of molluscum contagiosum with children children.

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)

[Antimicrobial effect of various calcium hydroxide on Porphyromonas endodontalis in vitro].

Science.gov (United States)

Du, Ting-ting; Qiu, Li-hong; Jia, Ge; Yang, Di; Guo, Yan

2012-04-01

To compare the antimicrobial activity of Endocal, calcium hydroxide paste, Calxyl, Vitapex on Porphyromonas endodontalis(P.e). (1) The antimicrobial activity of different calcium hydroxide on P.e was examined at different exposure times by dynamic nephelometry. (2) 85 freshly extracted single-rooted human teeth were selected and cut at the amelocemental junction. All roots were randomly divided into five groups. The bacteria were incubated in each canal and were sampled and counted before and after enveloping five kinds of intercanal medicine seeded. Student's t test, One-way ANOVA were used with SPSS11.0 software package for statistical analysis. The bacteria from each group were reduced significantly after intracanal medication (P<0.05). The antibacterial efficacy of Endocal and calcium hydroxide paste were superior to others under dynamic nephelometry test (P<0.05). Endocal, calcium hydroxide paste, Calxyl, Vitapex had strong inhibitory effect on P.e from infected root canals, and the rate of bacteria clearance was 95%. The antimicrobial activity of Endocal was significantly greater than others (P<0.05). Endocal, calcium hydroxide paste, Calxyl and Vitapex were effective for intercanal disinfection. The antibacterial activity of Endocal is greater than Vitapex.

Effect of pH on Separation of Solid Content from Paint Contained Wastewater by a Coagulant-flocculant Compound

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Mojtaba Semnani Rahbar

2014-05-01

Full Text Available Chemical wastewater treatment is one of the attracting and common methods for wastewater treatment among the currently employed chemical unit processes. The use of coagulant-flocculant compound is one of the efficient methods for separating of paint and recovery of water. In this research, it was introduced and the effect of pH on removal of solid content from solution was studied experimentally. For this purpose, sludge and suspended solid content of the solution were determined in a jar test by measurement of UV absorption of treated solution and solid separation percentage. The results showed that in pH range 9.5-10.5, maximum efficiency of solid content removal was up to 95%. Consequently, maximum paint removal was obtained in this range of pH. The separation of solid content of the solution was due to formation of aluminum hydroxide. As shown by the results, the reduction of potassium hydroxide as pH adjuster caused decrease of pH and consequently decreases of aluminum hydroxide and solid content removal.  

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...

Synthesis of thermoplastic elastomer using potassium persulfate and ammonium peroxydisulfate initiator

International Nuclear Information System (INIS)

Dewi Sondari; Agus Haryono; M Ghozali; Ahmad Randy; Kuntari Adi Suhardjo; Ariyadi B; Surasno

2010-01-01

Thermoplastic elastomer is polymeric material that has elastomer and thermoplastic properties. This material can be easily molded into finished and recyclable goods, thus environmentally safe for long term application. In this study we synthesize thermoplastic elastomer using two initiator that are potassium persulfate and ammonium peroxydisulfate with natural rubber to monomer (styrene/methyl methacrylate) ratio of 50 : 50 and 60 : 40 (v/v). The process of thermoplastic elastomer synthesis was conducted with emulsion grafting polymerization method for 6 hours at 65 °C. We used sodium dodecyl sulfate as emulsifier. FT-IR analysis result shows that grafting process had already occurred shown by new peaks that were observed in 1743 and 1519 cm"-"1. These peaks was assigned to carbonyl (C=O) group of methyl methacrylate and C=C benzene of styrene respectively. From "1H-NMR new peaks at δ = 7.1 ppm was aromatic proton from phenyl group of styrene, at δ = 3.5 ppm was methoxy proton of grafted methyl methacrylate acrylic group, and at δ = 5.1 ppm that is resonance of isoprene methine proton. This result showed that methyl methacrylate and styrene had already grafted onto natural rubber backbone. Initiator influenced grafting efficiency. Potassium persulfate gave 97.6 % grafting efficiency while ammonium peroxydisulfate gave 90.2 % grafting efficiency. (author)

A comparison of results from two mycology laboratories for the diagnosis of onychomycosis: a study of 85 cases in a geriatric population.

Science.gov (United States)

Scherer, William P; Scherer, Michael D

2004-01-01

An investigative study was performed to compare the results from two mycology laboratories for the diagnosis of onychomycosis in a geriatric population and to determine the possible pharmacologic treatments based on the two laboratories' results. In this study, 85 cases of suspected onychomycosis involving men and women 65 years and older from a nursing home setting in South Florida were used. Samples were taken from the hallux toenail and sent to two different mycology laboratories for fluorescent potassium hydroxide preparation and microscopic examination of a fungal culture. Of the 85 cases studied, the two mycology laboratories reported similar potassium hydroxide preparation results for 58.8% of the patients and similar fungal culture results for genus and species identification for 37.6% of the patients. When the potassium hydroxide preparation and fungal culture results were combined, the two mycology laboratories reported similar results for only 27.1% of the patients. As a result of the two mycology laboratories' findings, the possible US Food and Drug Administration-approved pharmacologic treatments may differ for 43.5% of the patients studied. The discrepancy between the two independent laboratories leaves physicians to question the reproducibility of fluorescent potassium hydroxide preparation and fungal culture analysis in a geriatric patient population for the diagnosis of onychomycosis.

Preparation of a sinterable beryllium oxide through decomposition of beryllium hydroxide (1963)

International Nuclear Information System (INIS)

Bernier, M.

1963-01-01

In the course of the present study, we have attempted to precise the factors which among the ones effective in the course of the preparation of the beryllium hydroxide and oxide and during the sintering have an influence on the final result: the density and homogeneity of the sintered body. Of the several varieties of hydroxides precipitated from a sulfate solution the β-hydroxide only is always contaminated with beryllium sulfate and cannot be purified even by thorough washing. We noticed that those varieties of the hydroxide (gel, α, β) have different decomposition rates; this behaviour is used to identify and even to dose the different species in (α, β) mixtures. The various hydroxides transmit to the resulting oxides the shape they had when precipitated. Accordingly the history of the oxide is revealed by its behaviour during its fabrication and sintering. By comparing the results of the sintering operation with the various measurements performed on the oxide powders we are led to the conclusion that an oxide obtained from beryllium hydroxide is sinterable under vacuum if the following conditions are fulfilled: the particle size must lie between 0.1 and 0.2 μ and the BeSO 4 content of the powder must be less than 0.25 per cent wt (expressed as SO 3 /BeO). The best fitting is obtained with the oxide issued from an α-hydroxide precipitated as very small aggregates and with a low sulfur-content. We have observed that this is also the case for the oxide obtained by direct calcination of beryllium sulfate. (author) [fr

Proapoptotic Role of Potassium Ions in Liver Cells

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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.

Comparative evaluation of different forms of calcium hydroxide in apexification

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Subhankar Ghosh

2014-01-01

Full Text Available Background: One out of every two children sustains a dental injury most often between 8 and 10 years of age. Majority of these teeth subsequently become non-vital and most often with immature apex. Management of these teeth is an enormous challenge for lack of apical stop. Calcium hydroxide in various formulations has maximum literature support in favor of "successful apexification or induced apical closure." Aim: The aim of the following study is to determine the efficacy of calcium hydroxide in a different formulation to induce apexification. Materials and Methods: The present study was undertaken on 51 children of 8-10 years of age (both sexes at Dr. R Ahmed Dental College and Hospital from April 2006 to March 2007. All children had one or two maxillary permanent central incisor (s, non-vital and apices open. In all the cases, apexification was attempted with either calcium hydroxide mixed with sterile distilled water, or calcium hydroxide plus iodoform in methyl cellulose base, or calcium hydroxide plus iodoform in polysilicone oil base. The success of apexification was determined on the basis of clinical and radiographic criteria. Results: In the pre-operative asymptomatic cases (72.55%, failure occurred in only 5.45% cases and pre-operative symptomatic cases failure rate was as high as 35.71%. Success rate was 94.6% in cases with narrow open apices, whereas 64.28% in wide open apices. In cases with pre-existing apical radiolucencies, successful apexification occurred in 63.63% and success rate was 92.5% in the cases without pre-existing apical radiolucencies. Average time consumed for apexification was minimum with calcium hydroxide plus iodoform in polysilicone oil base. Conclusion: The overall success rate observed to be 86.27%, which is in close proximity to the findings of most of the previous studies across the globe.

Comparative evaluation of different forms of calcium hydroxide in apexification.

Science.gov (United States)

Ghosh, Subhankar; Mazumdar, Dibyendu; Ray, Pradip Kumar; Bhattacharya, Bhaswar

2014-01-01

One out of every two children sustains a dental injury most often between 8 and 10 years of age. Majority of these teeth subsequently become non-vital and most often with immature apex. Management of these teeth is an enormous challenge for lack of apical stop. Calcium hydroxide in various formulations has maximum literature support in favor of successful apexification or induced apical closure. The aim of the following study is to determine the efficacy of calcium hydroxide in a different formulation to induce apexification. The present study was undertaken on 51 children of 8-10 years of age (both sexes) at Dr. R Ahmed Dental College and Hospital from April 2006 to March 2007. All children had one or two maxillary permanent central incisor (s), non-vital and apices open. In all the cases, apexification was attempted with either calcium hydroxide mixed with sterile distilled water, or calcium hydroxide plus iodoform in methyl cellulose base, or calcium hydroxide plus iodoform in polysilicone oil base. The success of apexification was determined on the basis of clinical and radiographic criteria. In the pre-operative asymptomatic cases (72.55%), failure occurred in only 5.45% cases and pre-operative symptomatic cases failure rate was as high as 35.71%. Success rate was 94.6% in cases with narrow open apices, whereas 64.28% in wide open apices. In cases with pre-existing apical radiolucencies, successful apexification occurred in 63.63% and success rate was 92.5% in the cases without pre-existing apical radiolucencies. Average time consumed for apexification was minimum with calcium hydroxide plus iodoform in polysilicone oil base. The overall success rate observed to be 86.27%, which is in close proximity to the findings of most of the previous studies across the globe.

Energy Conversion Alternatives Study (ECAS), Westinghouse phase 1. Volume 12: Fuel cells. [energy conversion efficiency of, for use in electric power plants

Science.gov (United States)

Warde, C. J.; Ruka, R. J.; Isenberg, A. O.

1976-01-01

A parametric assessment of four fuel cell power systems -- based on phosphoric acid, potassium hydroxide, molten carbonate, and stabilized zirconia -- has shown that the most important parameters for electricity-cost reduction and/or efficiency improvement standpoints are fuel cell useful life and power density, use of a waste-heat recovery system, and fuel type. Typical capital costs, overall energy efficiencies (based on the heating value of the coal used to produce the power plant fuel), and electricity costs are: phosphoric acid $350-450/kWe, 24-29%, and 11.7 to 13.9 mills/MJ (42 to 50 mills/kWh); alkaline $450-700/kWe, 26-31%, and 12.8 to 16.9 mills/MJ (46 to 61 mills/kWh); molten carbonate $480-650/kWe, 32-46%, and 10.6 to 19.4 mills/MJ (38 to 70 mills/kWh), stabilized zirconia $420-950/kWe, 26-53%, and 9.7 to 16.9 mills/MJ (35 to 61 mills/kWh). Three types of fuel cell power plants -- solid electrolytic with steam bottoming, molten carbonate with steam bottoming, and solid electrolyte with an integrated coal gasifier -- are recommended for further study.

Investigation on surface structure of potassium permanganate/nitric acid treated poly(tetrafluoroethylene)

International Nuclear Information System (INIS)

Fu, Congli; Liu, Shuling; Gong, Tianlong; Gu, Aiqun; Yu, Zili

2014-01-01

Highlights: • A new transformation (conversion) mechanism of PTFE surface from a hydrophobicity to a hydrophilicity was proposed through the treatment of KMnO 4 /HNO 3 . • Chemical reactions or defluorination of PTFE described in the reported paper was testified to be a misconceived conclusion by the combination of several testing measurements (IR, XPS, XRD and so on) in our present work. • Deposition of manganese oxide and/or manganese hydroxide on PTFE surface contributed to the hydrophilic property of the modified PTFE with KMnO 4 /HNO 3 treated. • The deposition thickness on the modified PTFE surface was about 5 μm, which was significantly helpful in enhancing the adhesive strength of PTFE with other materials. - Abstract: In the previous articles concerning the treatment of poly(tetrafluoroethylene) (PTFE) with potassium permanganate/nitric acid mixture, the conversion of a hydrophobic to a hydrophilic surface was partially assigned to the defluorination of PTFE and then the introduction of carbonyl and hydroxyl groups into the defluorinated sites. In the present work, PTFE sheets were treated with potassium permanganate/nitric acid, and the surfaces before and after treatment were comparatively characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The surface sediments of the treated PTFE were also determined by atomic absorption spectroscopy (AAS). The results indicate that the conversion of the hydrophobicity to the hydrophilicity on the modified PTFE surface is mainly due to the deposition of hydrophilic manganese oxides which covered the fluorocarbon surface, and no detectable chemical reactions of PTFE occur in the treating process

Investigation on surface structure of potassium permanganate/nitric acid treated poly(tetrafluoroethylene)

Energy Technology Data Exchange (ETDEWEB)

Fu, Congli; Liu, Shuling; Gong, Tianlong; Gu, Aiqun; Yu, Zili, E-mail: ziliyu@scu.edu.cn

2014-10-30

Highlights: • A new transformation (conversion) mechanism of PTFE surface from a hydrophobicity to a hydrophilicity was proposed through the treatment of KMnO{sub 4}/HNO{sub 3}. • Chemical reactions or defluorination of PTFE described in the reported paper was testified to be a misconceived conclusion by the combination of several testing measurements (IR, XPS, XRD and so on) in our present work. • Deposition of manganese oxide and/or manganese hydroxide on PTFE surface contributed to the hydrophilic property of the modified PTFE with KMnO{sub 4}/HNO{sub 3} treated. • The deposition thickness on the modified PTFE surface was about 5 μm, which was significantly helpful in enhancing the adhesive strength of PTFE with other materials. - Abstract: In the previous articles concerning the treatment of poly(tetrafluoroethylene) (PTFE) with potassium permanganate/nitric acid mixture, the conversion of a hydrophobic to a hydrophilic surface was partially assigned to the defluorination of PTFE and then the introduction of carbonyl and hydroxyl groups into the defluorinated sites. In the present work, PTFE sheets were treated with potassium permanganate/nitric acid, and the surfaces before and after treatment were comparatively characterized by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The surface sediments of the treated PTFE were also determined by atomic absorption spectroscopy (AAS). The results indicate that the conversion of the hydrophobicity to the hydrophilicity on the modified PTFE surface is mainly due to the deposition of hydrophilic manganese oxides which covered the fluorocarbon surface, and no detectable chemical reactions of PTFE occur in the treating process.

Functionalization of lanthanum hydroxide nanowires by atom transfer radical polymerization

International Nuclear Information System (INIS)

Zhou Mi; Yuan Jinying; Yuan Weizhong; Yin Yingwu; Hong Xiaoyin

2007-01-01

Atom transfer radical polymerization (ATRP) has been used to prepare a core-shell hybrid nanostructure successfully: a hard core of single-crystalline lanthanum hydroxide nanowires and a soft shell of polystyrene (PS) brushes. Transmission electron microscopy (TEM) images indicated that the resulting products presented special structures and different thicknesses of polymer layers. The chemical components and grafted PS quantities of the samples were measured by Fourier transform infrared (FT-IR) spectroscopy and thermogravimetric analysis (TGA). The polymers showed narrow polydispersity, which proved that the lanthanum hydroxide nanowires initiated the 'living'/controlled polymerization of styrene. With the modifiability of lanthanum hydroxide nanowires, the solubility increased, which affords a new way to functionalize nanowires

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.

Structural perturbation of diphtheria toxoid upon adsorption to aluminium hydroxide adjuvant

NARCIS (Netherlands)

Regnier, M.; Metz, B.; Tilstra, W.; Hendriksen, C.; Jiskoot, W.; Norde, W.; Kersten, G.

2012-01-01

Aluminium-containing adjuvants are often used to enhance the potency of vaccines. In the present work we studied whether adsorption of diphtheria toxoid to colloidal aluminium hydroxide induces conformational changes of the antigen. Diphtheria toxoid has a high affinity for the aluminium hydroxide

Electron impact study of potassium hydroxide

International Nuclear Information System (INIS)

Vuskovic, L.; Trajmar, S.

1979-01-01

An ''elastic'' scattering study for low impact energies (5--20 ev) is reported for electron impact excitation of KOH. The ''elastic'' scattering is regarded as the sum of elastic rotational and vibrational contributions to the scattering

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.

Effect of calcium hydroxide on slip casting behaviour

OpenAIRE

Şakar‐Deliormanlı, Aylin; Yayla, Zeliha

2004-01-01

The effect of calcium hydroxide addition on the casting performance of ceramic slips for sanitary ware was studied. Powder composed of feldspar (24 wt.%), quartz (24 wt.%), kaolin (35 wt.%) and ball clay (17 wt.%) was mixed with water to contain 65 wt.% of solids (specific density 1800 g/l). Either Ca(OH)2 or Na2CO3 was added at concentrations ranging between 0.060 and 0.085 wt.% and the slurries were dispersed by the optimum addition of sodium silicate. Calcium hydroxide in presence of sodiu...

Synthesis of Zn–Fe layered double hydroxides via an oxidation process and structural analysis of products

Energy Technology Data Exchange (ETDEWEB)

Morimoto, Kazuya, E-mail: kazuya.morimoto@aist.go.jp [Institute for Geo-Resources and Environment, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8567 (Japan); Tamura, Kenji [Environmental Remediation Materials Unit, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Anraku, Sohtaro [Graduate School of Engineering, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo 060-8628 (Japan); Sato, Tsutomu [Faculty of Engineering, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo 060-8628 (Japan); Suzuki, Masaya [Institute for Geo-Resources and Environment, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Higashi, Tsukuba, Ibaraki 305-8567 (Japan); Yamada, Hirohisa [Environmental Remediation Materials Unit, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

2015-08-15

The synthesis of Zn–Fe(III) layered double hydroxides was attempted, employing different pathways using either Fe(II) or Fe(III) species together with Zn as the initial reagents. The product derived from the synthesis employing Fe(II) was found to transition to a Zn–Fe(III) layered double hydroxides phase following oxidation process. In contrast, the product obtained with Fe(III) did not contain a layered double hydroxides phase, but rather consisted of simonkolleite and hydrous ferric oxide. It was determined that the valency of the Fe reagent used in the initial synthesis affected the generation of the layered double hydroxides phase. Fe(II) species have ionic radii and electronegativities similar to those of Zn, and therefore are more likely to form trioctahedral hydroxide layers with Zn species. - Graphical abstract: The synthesis of Zn–Fe(III) layered double hydroxides was attempted, employing different pathways using either Fe(II) or Fe(III) species together with Zn as the initial reagents. - Highlights: • Iron valency affected the generation of Zn–Fe layered double hydroxides. • Zn–Fe layered double hydroxides were successfully synthesized using Fe(II). • Fe(II) species were likely to form trioctahedral hydroxide layers with Zn species.

Vibrational dynamics of aqueous hydroxide solutions probed using broadband 2DIR spectroscopy

International Nuclear Information System (INIS)

Mandal, Aritra; Tokmakoff, Andrei

2015-01-01

We employed ultrafast transient absorption and broadband 2DIR spectroscopy to study the vibrational dynamics of aqueous hydroxide solutions by exciting the O–H stretch vibrations of the strongly hydrogen-bonded hydroxide solvation shell water and probing the continuum absorption of the solvated ion between 1500 and 3800 cm −1 . We observe rapid vibrational relaxation processes on 150–250 fs time scales across the entire probed spectral region as well as slower vibrational dynamics on 1–2 ps time scales. Furthermore, the O–H stretch excitation loses its frequency memory in 180 fs, and vibrational energy exchange between bulk-like water vibrations and hydroxide-associated water vibrations occurs in ∼200 fs. The fast dynamics in this system originate in strong nonlinear coupling between intra- and intermolecular vibrations and are explained in terms of non-adiabatic vibrational relaxation. These measurements indicate that the vibrational dynamics of the aqueous hydroxide complex are faster than the time scales reported for long-range transport of protons in aqueous hydroxide solutions

Variation in photoreactivity of iron hydroxides taken from an acidic mountain stream

International Nuclear Information System (INIS)

Hrncir, D.C.; McKnight, D.

1998-01-01

The photoreduction of iron hydroxides is known to exert significant influence over many biogeochemical processes in streams impacted by acid main drainage. Using laboratory and in-stream measurements, the variation in reactivity of iron hydroxides taken from a stream receiving acid mine drainage (AMD) was studied. The reactivity decreased for material collected at sites progressively downstream from the AMD inflow. In the presence of two simple organic ligands, photoreduction increased for the fresher iron hydroxides but remained unchanged for the older hydroxides. The importance of ligand coordination to the enhancement of photoreduction in natural waters was further demonstrated in experiments using two types of fulvic acids. In-stream measurements of hydrogen peroxide concentration are consistent with the conclusions drawn from the batch experiments. Iron hydroxides were observed to age over time, becoming less photoreactive. This aging was accompanied by an increase in crystallinity. The loss of photoreactivity for the older material can be explained by a decrease in the number of active surface sites, a change in the nature of the surface sites, or a combination of both

Implementation of ferric hydroxide-based media for removal of toxic metalloids

Science.gov (United States)

Szlachta, Małgorzata; Wójtowicz, Patryk

2017-11-01

Effective removal of inorganic arsenic species is possible by application of the sorption technique with the use of iron-based sorbents. This study investigates the removal of arsenic(III) and arsenic(V) from an aqueous solution by application of a granular ferric hydroxide-based sorbent. The performance of tested media was evaluated based on the batch and fixed-bed adsorption studies. The efficiency of the process was determined with various treatment times, adsorbent doses, initial concentrations of arsenic and various solution temperatures. The obtained adsorption data were fitted with pseudo-first and second-order kinetic models and Langmuir and Freundlich isotherm equations. It was observed that the overall arsenite removal was lower when compared to the arsenate, and all tested operating parameters influenced the process efficiency. The experiments under dynamic conditions showed high treatment capacity and stability of tested adsorbent over a long period of time.

The effect of foliar feeding of potassium salts and urea in spinach on gas exchange, leaf yield and quality

Directory of Open Access Journals (Sweden)

Edward Borowski

2012-12-01

Full Text Available In a pot experiment conducted in a phytotron, the effectiveness of foliar feeding of different potassium salts, with and without the addition of 0.5% CO(NH22, in spinach (Spinacia oleracea L. was investigated. Potassium was applied 3 times in the form of 1% solutions KCl, KNO3, K2SO4 and C6H5K3O7•H2O, compared to water as the control treatment. The obtained results show that foliar feeding of potassium salts in spinach is an efficient method of supplementing the level of K+ in plants during vegetation. Plants fed with KNO3 had the highest content of potassium in leaves, and those fertilized with K2SO4, C6H5K3O7 × H2O and KCl had an only slightly lower potassium content. The application of potassium salts resulted in more intensive gas exchange in leaves (stomatal conductance, photosynthesis, transpiration and, as a consequence of that, increased leaf yield. Potassium nitrate and citrate influenced most effectively the abovementioned processes. The treatment of spinach with potassium salts resulted in an increased content of protein, chlorophyll, carotenoids, nitrates and iron as well as a decreased content of vitamin C and calcium in leaves.

Evaluation of crop residues on potassium kinetics in an acid soil and potassium use efficiency in potato-garlic sequence using tracer 86Rb

International Nuclear Information System (INIS)

Sud, K.C.

2005-01-01

Greenhouse and laboratory studies were conducted on an acid soil in order to evaluate the role of two crop residues i.e. paddy and wheat along with farmyard manure on potassium kinetics and its availability in the potato-garlic sequence using tracer 86 Rb. Under rapid equilibrium, application of crop residues of paddy, wheat straw and FYM were able to enhance soil pH and organic carbon content. In addition, their application helped in enhancing soil K availability indices like water soluble, available and non-exchangeable -K. This was further augmented by the Q/I studies using 86 Rb where application of organic residues helped in lowering the potassium buffering capacity of the soil. Greenhouse study supplemented the results obtained from laboratory study where application of crop residues/FYM were able to improve the potato yield significantly and maintained higher concentration of K in potato leaf at early growth stages. A significant correlation was obtained between leaf K and haulms-K with that of 86 Rb activities in potato leaf at 35 days and 86 Rb absorbed in the haulms, respectively. Residues/ FYM and PK application to potato left sufficient residual effect on succeeding garlic crop. In potato-garlic sequence, K recovery was highest with FYM while N and P recoveries were higher with wheat residues. The nutrient recoveries with PK application followed law of diminishing returns. (author)

COMBINED ALUMINIUM SULFATE/HYDROXIDE PROCESS FOR ...

African Journals Online (AJOL)

sulfate, and used for fluoride removal from water by combining with Nalgonda Technique. ... effects on human health and could result in fluorosis. ... [23], nanoscale aluminium oxide hydroxide (AlOOH) [24] and natural zeolite [25], were among.

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.

F-radiographic study of uranium distribution in iron hydroxides from crusts of weathering

International Nuclear Information System (INIS)

Zhmodik, S.M.; Mironov, A.G.; Nemirovskaya, N.A.

1980-01-01

Presented are the results of study of uranium concentrations and peculiarities of its distribution in iron hydroxides from crusts of weathering of aluminium silicate and carbonate rocks. The age of one crusts of weathering is Quaternary, of others - Tertiary. The effect of climatic conditions, composition of source rocks, hydrochemical zoning of the crust of weathering on the uranium fixation by iron hydroxides has been studied. Gamma-spectroscopy, luminescence and autoradiography methods have been used. The mechanism of formation of increased uranium concentrations in iron hydroxides is considered. A conclusion is made that increased uranium concentrations in iron hydroxides may appear in the process of weathering both of aluminium-silicate and carbonate-containing rocks as a result of uranium sorption by fine dispersed iron hydrates. The use of iron hydroxides with increased (anomalous) uranium concentrations as a direct search feature without additional investigations can lead to wrong conclusions

Alkali metal and alkali metal hydroxide intercalates of the layered transition metal disulfides

International Nuclear Information System (INIS)

Kanzaki, Y.; Konuma, M.; Matsumoto, O.

1981-01-01

The intercalation reaction of some layered transition metal disulfides with alkali metals, alkali metal hydroxides, and tetraalkylammonium hydroxides were investigated. The alkali metal intercalates were prepared in the respective metal-hexamethylphosphoric triamide solutions in vaccuo, and the hydroxide intercalates in aqueous hydroxide solutions. According to the intercalation reaction, the c-lattice parameter was increased, and the increase indicated the expansion of the interlayer distance. In the case of alkali metal intercalates, the expansion of the interlayer distance increased continuously, corresponding to the atomic radius of the alkali metal. On the other hand, the hydroxide intercalates showed discrete expansion corresponding to the effective ionic radius of the intercalated cation. All intercalates of TaS 2 amd NbS 2 were superconductors. The expansion of the interlayer distance tended to increase the superconducting transition temperature in the intercalates of TaS 2 and vice versa in those of NbS 2 . (orig.)

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

Ultra-fast and highly efficient removal of cadmium ions by magnetic layered double hydroxide/guargum bionanocomposites.

Science.gov (United States)

Dinari, Mohammad; Tabatabaeian, Reyhane

2018-07-15

Finding effective methodologies for the removal of heavy metals from contaminated water are really significant. Facile and "green" techniques for adsorbents fabrication are in high demand to satisfy a wide range of practical applications. This report presents of an efficient method for preparing Fe 3 O 4 @ layered double hydroxide@ guargum bionanocomposites (GLF-BNCs). First of all, the LDH coated Fe 3 O 4 nanoparticles were simply synthesized, using ultrasonic irradiation. The citrate coated Fe 3 O 4 nanoparticles which were under negative charging and LDH nanocrystals which were charged positively make electrostatic interaction which formed a stable self-assembly component, and then guargum as a biopolymer were linked onto Fe 3 O 4 @LDH via an in situ growth method. Furthermore, the GLF-BNCs had the ability to remove cadmium ions (Cd 2+ ) from the aqueous solutions. Adsorption studies indicate that the Langmuir isotherm model and the kinetic model in pseudo-second order were appropriate for Cd(II) removal. The maximum Cd(II) adsorption capacity of the GLF8% was 258 mg g -1 . The Cd(II) was adsorbed from aqueous solutions very quickly with the contact time of 5 min by the GLF 8%, suggesting that GLF-BNCs may be a promising adsorbent for removing Cd(II) from wastewater. The effect of Fe 3 O 4 @LDH contents (2, 4 and 8 wt.%) on the thermal, physicomechanical, and morphological properties of guargum were investigated by Fourier transform infrared spectroscopy, X-ray diffraction (XRD), thermal gravimetric analysis (TGA), field emission scanning electron microscopy, transmission electron microscopy (TEM), Energy-dispersive X-ray spectroscopy and Brunauer-Emmett-Teller (BET) specific surface area techniques. The TEM results indicated that the LDH platelets are distributed within the polymer matrix. Copyright © 2018 Elsevier Ltd. All rights reserved.

Natural potassium as a teaching material

International Nuclear Information System (INIS)

Akatsu, Eiko

1993-07-01

An experience of an educational experiment is presented with results and discussion. It was performed in the introductory course of nuclear energy in the Nuclear Education Center of Japan Atomic Energy Research Institute. Purpose of the experiment is understanding disintegration rate (Bq, radioactivity or λN) through measurement of low radioactivity of natural potassium. It was accomplished through calculation of the radioactivity of a measuring known sample and counting efficiency during measurement. The students in the training course had great variety and most students did not have preliminary knowledge. But they said in the questionnaire having almost understood the experiment; and some students enjoyed it. (author)

Determination of haloacetic acids in water using layered double hydroxides as a sorbent in dispersive solid-phase extraction followed by liquid chromatography with tandem mass spectrometry.

Science.gov (United States)

Alsharaa, Abdulnaser; Sajid, Muhammad; Basheer, Chanbasha; Alhooshani, Khalid; Lee, Hian Kee

2016-09-01

In the present study, highly efficient and simple dispersive solid-phase extraction procedure for the determination of haloacetic acids in water samples has been established. Three different types of layered double hydroxides were synthesized and used as a sorbent in dispersive solid-phase extraction. Due to the interesting behavior of layered double hydroxides in an acidic medium (pH˂4), the analyte elution step was not needed; the layered double hydroxides are simply dissolved in acid immediately after extraction to release the analytes which are then directly introduced into a liquid chromatography with tandem mass spectrometry system for analysis. Several dispersive solid-phase extraction parameters were optimized to increase the extraction efficiency of haloacetic acids such as temperature, extraction time and pH. Under optimum conditions, good linearity was achieved over the concentration range of 0.05-100 μg/L with detection limits in the range of 0.006-0.05 μg/L. The relative standard deviations were 0.33-3.64% (n = 6). The proposed method was applied to different water samples collected from a drinking water plant to determine the concentrations of haloacetic acids. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Nickel oxide/hydroxide nanoplatelets synthesized by chemical precipitation for electrochemical capacitors

International Nuclear Information System (INIS)

Wu, M.-S.; Hsieh, H.-H.

2008-01-01

Nickel hydroxide powder prepared by directly chemical precipitation method at room temperature has a nanoplatelet-like morphology and could be converted into nickel oxide at annealing temperature higher than 300 deg. C, confirmed by the thermal gravimetric analysis and X-ray diffraction. Annealing temperature influences significantly both the electrical conductivity and the specific surface area of nickel oxide/hydroxide powder, and consequently determines the capacitor behavior. Electrochemical capacitive behavior of the synthesized nickel hydroxide/oxide film is investigated by cyclic voltammetry and electrochemical impedance spectroscope methods. After 300 deg. C annealing, the highest specific capacitance of 108 F g -1 is obtained at scan rate of 10 mV s -1 . When annealing temperature is lower than 300 deg. C, the electrical conductivity of nickel hydroxide dominates primarily the capacitive behavior. When annealing temperature is higher than 300 deg. C, both electrical conductivity and specific surface area of the nickel oxide dominate the capacitive behavior

Microwave assisted alkali-catalyzed transesterification of Pongamia pinnata seed oil for biodiesel production.

Science.gov (United States)

Kumar, Ritesh; Kumar, G Ravi; Chandrashekar, N

2011-06-01

In this study, microwave assisted transesterification of Pongamia pinnata seed oil was carried out for the production of biodiesel. The experiments were carried out using methanol and two alkali catalysts i.e., sodium hydroxide (NaOH) and potassium hydroxide (KOH). The experiments were carried out at 6:1 alcohol/oil molar ratio and 60°C reaction temperature. The effect of catalyst concentration and reaction time on the yield and quality of biodiesel was studied. The result of the study suggested that 0.5% sodium hydroxide and 1.0% potassium hydroxide catalyst concentration were optimum for biodiesel production from P. pinnata oil under microwave heating. There was a significant reduction in reaction time for microwave induced transesterification as compared to conventional heating. Copyright © 2011 Elsevier Ltd. All rights reserved.

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)

Nickel hydroxide modified electrodes for urea determination

Directory of Open Access Journals (Sweden)

Luiz Henrique Dall´Antonia

2007-03-01

Full Text Available Nickel hydroxide films were prepared by electrodeposition from a solution Ni(NO32 0,05 mol L ?¹ on ITO electrodes (Tin oxide doped with Indium on PET-like plastic film, applying a current of - 0,1 A cm ?² during different time intervals between 1800 and 7200 s. The electrochemical behavior of the nickel hydroxide electrode was investigated through a cyclic voltammogram, in NaOH 1,0 mol L ?¹, where it was observed two peaks in the profile in 0,410 and 0,280 V, corresponding to redox couple Ni(II/Ni(III. A sensor for urea presenting a satisfactory answer can be obtained when, after the deposit of the film of Ni(OH2 on the electrode of nickel, it is immersed in a solution of NaOH 1,0 mol L ?¹ and applying a potential of + 0,435 V, where the maximum of the anodic current occurs in the cyclic voltammogram. Analyzing the results it can be observed that, for a range of analite concentration between 5 to 50 m mol L ?¹, the behavior is linear and the sensibility found was of 20,3 mA cm?² (mol L?¹?¹, presenting reproducibility confirming the nickel hydroxide electrodes utilization for the determination of urea.

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.

Study of the Efficiency of Arsenic Removal from Drinking Water by Granular Ferric Hydroxide (GFH

Directory of Open Access Journals (Sweden)

A.R Asgari

2012-05-01

Full Text Available

Background and Objective

Pollution of surface and ground water to arsenic (As has been reported from many parts of the world and in some regions of Iran especially in Kurdistan province. Natural pollution of water to As is in fact dependent to geological characteristics of a region. To day, various methods have been recommended for As removal that each of which has special advantages and drawbacks. Granular ferric hydroxide (GFH is a relatively new adsorbent available in market which is principally introduced for As removal.

Methods

This study was an applied survey in which the effects of changing contact time, As concentration, adsorbent weight, pH as well as the effect of sulfate and chloride ions in arsenic removal were determined. Moreover, the model of absorption by GFH was studied and compared with Freundlich and Langmuir models. Raw data were analyzed by Excel and SPSS softwares.

Results

Results showed that As adsorption by GFH imitate both the Freundlich and Langmuir equations (with R² >0.95. Optimum PH was 7.5 and duration of the process about 30 minutes was sufficient for optimum removal of As. It was also found that efficiency of As removal was high when small amounts of adsorbent were used. Furthermore, sulfate and chloride ions in concentrations used in this study had no noticeable effect on As removal and Fe added during process remains in the water more than the standard value (0.3 mg/l.

Conclusion

According to this study, GFH could be considered as a suitable adsorbent for As removal from polluted water resources because of its high performance without any needs to PH adjustment. However, there are few drawbacks such as Fe addition and relatively high initial cost.

TiO₂ Nanowire Networks Prepared by Titanium Corrosion and Their Application to Bendable Dye-Sensitized Solar Cells.

Science.gov (United States)

Jin, Saera; Shin, Eunhye; Hong, Jongin

2017-10-12

TiO₂ nanowire networks were prepared, using the corrosion of Ti foils in alkaline (potassium hydroxide, KOH) solution at different temperatures, and then a further ion-exchange process. The prepared nanostructures were characterized by field emission scanning electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. The wet corroded foils were utilized as the photoanodes of bendable dye-sensitized solar cells (DSSCs), which exhibited a power conversion efficiency of 1.11% under back illumination.

Biodiesel Production from Chlorella protothecoides Oil by Microwave-Assisted Transesterification

OpenAIRE

G?lyurt, Mustafa ?mer; ?z?imen, Didem; ?nan, Benan

2016-01-01

In this study, biodiesel production from microalgal oil by microwave-assisted transesterification was carried out to investigate its efficiency. Transesterification reactions were performed by using Chlorella protothecoides oil as feedstock, methanol, and potassium hydroxide as the catalyst. Methanol:oil ratio, reaction time and catalyst:oil ratio were investigated as process parameters affected methyl ester yield. 9:1 methanol/oil molar ratio, 1.5% KOH catalyst/oil ratio and 10 min were opti...

Preparation of hydroxide ion conductive KOH–layered double hydroxide electrolytes for an all-solid-state iron–air secondary battery

Directory of Open Access Journals (Sweden)

Taku Tsuneishi

2014-06-01

Full Text Available Anion conductive solid electrolytes based on Mg–Al layered double hydroxide (LDH were prepared for application in an all-solid-state Fe–air battery. The ionic conductivity and the conducting ion species were evaluated from impedance and electromotive force measurements. The ion conductivity of LDH was markedly enhanced upon addition of KOH. The electromotive force in a water vapor concentration cell was similar to that of an anion-conducting polymer membrane. The KOH–LDH obtained was used as a hydroxide ion conductive electrolyte for all-solid-state Fe–air batteries. The cell performance of the Fe–air batteries was examined using a mixture of KOH–LDH and iron-oxide-supported carbon as the negative electrode.

The effect of polymers onto the size of zinc layered hydroxide salt and its calcined product

Science.gov (United States)

Hussein, Mohd Zobir bin; Ghotbi, Mohammad Yeganeh; Yahaya, Asmah Hj; Abd Rahman, Mohd Zaki

2009-02-01

Zinc hydroxide nitrate, a brucite-like layered material was synthesized using pH control method. Poly(vinyl alcohol) and poly(ethylene glycol) were used at various percentages as size decreasing agents during the synthesis of zinc hydroxide nitrate. SEM and PXRD showed the decrease of size and thickness of the resultant zinc hydroxide nitrates. TG and surface area data confirmed the decrease of the particle sizes, too. When zinc hydroxide nitrates were heat treated at 500 °C, the physical properties of nano zinc oxides obtained depended on the parent material, zinc hydroxide nitrate.

A new method of body habitus correction for total body potassium measurements

International Nuclear Information System (INIS)

O'Hehir, S; Green, S; Beddoe, A H

2006-01-01

This paper describes an accurate and time-efficient method for the determination of total body potassium via a combination of measurements in the Birmingham whole body counter and the use of the Monte Carlo n-particle (MCNP) simulation code. In developing this method, MCNP has also been used to derive values for some components of the total measurement uncertainty which are difficult to quantify experimentally. A method is proposed for MCNP-assessed body habitus corrections based on a simple generic anthropomorphic model, scaled for individual height and weight. The use of this model increases patient comfort by reducing the need for comprehensive anthropomorphic measurements. The analysis shows that the total uncertainty in potassium weight determination by this whole body counting methodology for water-filled phantoms with a known amount of potassium is 2.7% (SD). The uncertainty in the method of body habitus correction (applicable also to phantom-based methods) is 1.5% (SD). It is concluded that this new strategy provides a sufficiently accurate model for routine clinical use

A new method of body habitus correction for total body potassium measurements

Energy Technology Data Exchange (ETDEWEB)

O' Hehir, S [University Hospital Birmingham Foundation NHS Trust, Birmingham (United Kingdom); Green, S [University Hospital Birmingham Foundation NHS Trust, Birmingham (United Kingdom); Beddoe, A H [University Hospital Birmingham Foundation NHS Trust, Birmingham (United Kingdom)

2006-09-07

This paper describes an accurate and time-efficient method for the determination of total body potassium via a combination of measurements in the Birmingham whole body counter and the use of the Monte Carlo n-particle (MCNP) simulation code. In developing this method, MCNP has also been used to derive values for some components of the total measurement uncertainty which are difficult to quantify experimentally. A method is proposed for MCNP-assessed body habitus corrections based on a simple generic anthropomorphic model, scaled for individual height and weight. The use of this model increases patient comfort by reducing the need for comprehensive anthropomorphic measurements. The analysis shows that the total uncertainty in potassium weight determination by this whole body counting methodology for water-filled phantoms with a known amount of potassium is 2.7% (SD). The uncertainty in the method of body habitus correction (applicable also to phantom-based methods) is 1.5% (SD). It is concluded that this new strategy provides a sufficiently accurate model for routine clinical use.

Production of free fatty acids from waste oil by application of ultrasound

Energy Technology Data Exchange (ETDEWEB)

Lima, Larissa P.; Santos, Francisco F.P.; Costa, Enio; Fernandes, Fabiano A.N. [Universidade Federal do Ceara, Departamento de Engenharia Quimica, Fortaleza, CE (Brazil)

2012-12-15

This paper evaluates the production of free fatty acids (FFAs) from waste oil by means of low-frequency high-intensity ultrasound application under atmospheric pressure. To evaluate the potential of this technology, the reaction between waste palm oil and ethanol was carried out. Response surface methodology (RSM) was used to evaluate the influence of alcohol-to-oil weight ratio, potassium hydroxide-to-oil weight ratio, and temperature on the yield of waste oil into FFA. Analysis of the operating conditions by RSM showed that the most important operating conditions affecting the reaction were ethanol-to-oil weight ratio and potassium hydroxide-to-oil weight ratio. The highest yield observed was of 97.3 % after 45 min of reaction. The best operating condition was obtained by applying an ethanol-to-oil weight ratio of 2.4, a potassium hydroxide-to-oil weight ratio of 0.3, and temperature of 60 C. (orig.)

EFFICACY OF DIFFERENT ENDODONTIC IRRIGATION PROTOCOLS IN CALCIUM HYDROXIDE REMOVAL

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Elka N. Radeva

2016-10-01

Full Text Available Introduction: Calcium hydroxide is widely used in the field of endodontics as a temporary root canal filling. This medicament significantly increases pH and optimizes the treatment outcome. Its total removal before final obturation is very important. Otherwise it could affect the hermetic filling and respectively the endodontic success. Aim: To evaluate the most effective irrigation protocol of calcium hydroxide removal from root canals. Materials and methods: In this study 36 single root canal teeth were observed. They were randomly divided into three groups (n=10 each group according to the technique applied for calcium hydroxide removal - manual irrigation, irrigation and Revo-S rotary instrumentation; and passive ultrasonic irrigation, and a control group (n=6 – irrigation with distilled water only. After calcium hydroxide removals following the procedures above, teeth were separated longitudinally in a buccal-lingual direction and remnants of medicaments were observed in the apical, middle and coronal part of each tooth. Then all of the specimens were observed using scanning electron microscopy and evaluated by a specified scale. The results have undergone statistical analysis. Results: In the case of calcium hydroxide in the apex and in the middle with highest average is Revo-S, followed by Ultrasonic and irrigation. In the coronal part the highest average belongs to Revo-S, irrigation and Ultrasonic. In all groups the highest average is represented by control group. Conclusion: There is not a universal technique for removal of intracanal medicaments and applying more than one protocol is required.

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...

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 ...

Hydrothermal synthesis and formation mechanism of hexagonal yttrium hydroxide fluoride nanobundles

International Nuclear Information System (INIS)

Tian, Li; Sun, QiLiang; Zhao, RuiNi; He, HuiLin; Xue, JianRong; Lin, Jun

2013-01-01

Graphical abstract: The formation of yttrium hydroxide fluorides nanobundles can be expressed as a precipitation transformation from cubic NaYF 4 to hexagonal NaYF 4 and to hexagonal Y(OH) 2.02 F 0.98 owing to ion exchange. - Highlights: • Novel Y(OH) 2.02 F 0.98 nanobundles have been successfully prepared by hydrothermal method. • The branched nanobundles composed of numerous oriented-attached nanoparticles has been studied. • The growth mechanism is proposed to be ion exchange and precipitation transformation. - Abstract: This article presents the fabrication of hexagonal yttrium hydroxide fluoride nanobundles via one-pot hydrothermal process, using yttrium nitrate, sodium hydroxide and ammonia fluoride as raw materials to react in propanetriol solvent. The X-ray diffraction pattern clearly reveals that the grown product is pure yttrium hydroxide fluoride, namely Y(OH) 2.02 F 0.98 . The morphology and microstructure of the synthesized product is testified to be nanobundles composed of numerous oriented-attached nanoparticles as observed from the field emission scanning electron microscopy (FESEM). The chemical composition was analyzed by the energy dispersive spectrum (EDS), confirming the phase transformation of the products which was clearly consistent with the result of XRD analysis. It is proposed that the growth of yttrium hydroxide fluoride nanobundles be attributed to ion exchange and precipitation transformation

The production and use of citric acid for the removal of potassium from the iron ore concentrate of the Sishen Iron Ore Mine, South Africa

Directory of Open Access Journals (Sweden)

Peter J. Williams

2010-04-01

Full Text Available The depletion of the richer iron ore worldwide has made it necessary to process lower quality iron ore. Certain substances, such as potassium, contained within the lower quality iron ore, have a detrimental effect on the smelting process during steel manufacturing. Therefore, international steel-making companies charge penalties when purchasing iron ore concentrates containing high concentrations of potassium. To date, lower quality iron ore has been blended with high quality iron ore in an attempt to alleviate the potassium concentrations in the export iron ore; however, the ratio of low quality iron ore to high quality iron ore is increasing, thereby becoming an escalating problem within the economic functioning of the Sishen Iron Ore Mine. It has, therefore, become necessary to develop an economically viable and environmentally friendly process to reduce the high potassium concentrations contained in the iron ore concentrate of the Sishen Iron Ore Mine. In this study, we compared solid substrate and submerged fermentation using Aspergillus niger for the production of citric acid, which is used for the chemical leaching of potassium from the iron ore concentrate. It was found that submerged fermentation proved to be more economical and efficient, producing a maximum citric acid concentration of 102.3 g/L in 96 h of fermentation. ‘Heap leaching’ simulation experiments were found to be uneconomical, due to the required addition of fungal growth medium every 5 days as a result of growth factor depletion within this time; however, this process removed 17.65% of the potassium from the iron ore concentrate. By contrast, chemical leaching of potassium from the iron ore concentrate proved to be most efficient when using a 1 mol citric acid leaching solution at 60 ºC, removing 23.53% of the potassium contained within the iron ore concentrate. Therefore, the most economical and efficient process for the removal of potassium from the iron

Agronomic efficiency of potassium fertilization in lettuce fertilized with alternative nutrient sources Eficiência agronômica da adubação potássica na alface adubada com fontes alternativas de nutrientes

Directory of Open Access Journals (Sweden)

Douglas Ramos Guelfi-Silva

2013-06-01

Full Text Available The aim of this study was to evaluate the effect of alternative sources of nutrients on the nutrition, yield and efficiency of potassium fertilization in lettuce. The experiment was carried out in a greenhouse, using 3.7 kg pots filled with a dystrophic red-yellow Latosol of medium texture. The experimental design was randomized, with treatments divided into a 4 x 6 factorial: four doses of potassium (0; 200; 400; 600 kg ha-1 K2O and six alternative sources of nutrients (breccia, ultramafic, biotite schist, phlogopite, and mining and Chapada by-products, with four replications. Content and accumulation were determined for potassium (K, copper (Cu, zinc (Zn and nickel (Ni in the lettuce shoots, and from these data two indices were calculated for the efficiency of potassium as a fertilizer. The application of increasing values of alternative sources of nutrients promoted improvements in nutrition and increases in lettuce yield. The efficiency of potassium fertilization decreased with the increase in values of potassium taken from alternative nutrient sources, with the mining by-products and the ultramafic being superior to the other sources. Crushed silicate rocks and mining by-products can therefore both be used as fertilizer in organic and conventional production systems.O objetivo desse estudo foi avaliar o efeito da aplicação de fontes alternativas de nutrientes na nutrição, produção e eficiência da adubação potássica na alface. O experimento foi conduzido em casa de vegetação, em vasos com 3,7 kg preenchidos com um Latossolo Vermelho Amarelo distrófico de textura média. O delineamento experimental foi inteiramente casualizado e os tratamentos foram distribuídos em arranjo fatorial 4 x 6, sendo quatro doses de potássio (0; 200; 400; 600 kg ha-1 de K2O e seis fontes alternativas de nutrientes (brecha, ultramáfica, biotita xisto, flogopitito, subproduto de mineração e subproduto de chapada, com quatro repetições. Foram

Evaluation of preservative effectiveness of gallic acid derivatives in aluminum hydroxide gel-USP

Directory of Open Access Journals (Sweden)

Anurag Khatkar

2013-01-01

Full Text Available Background: Preservatives are added to most of the pharmaceutical preparations to prevent them from deterioration throughout their shelf life. Literature reveals that the common synthetic preservatives have many limitations, such as development of microbial resistance (in due course of time and several serious side-effects. Aim: The aim of this study is to find out new preservatives synthesized from natural sources, which may have better efficiency than the existing synthetic preservatives. The derivatives of naturally occurring gallic acid were subjected for their preservative efficacy study. Their preservative efficiency was evaluated and compared with the standard parabens. Materials and Methods: The selected amide, anilide and ester derivatives of gallic acid were subjected to preservative efficacy testing in an official antacid preparation, {aluminum hydroxide gel-USP (United States Pharmacopoeia} against Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Candida albicans, and Aspergillus niger as representative challenging microorganisms as per USP 2004 guidelines. Results: The selected derivatives were found to be effective against all selected strains and showed preservative efficacy comparable to that of standard and even better in case E. coli, C. albicans and A. niger. The 8-hydroxy quinoline ester derivative showed better preservative efficacy than standard as well as other derivatives. Conclusion: The newly synthesized gallic acid preservatives were found to be effective in the proposed pharmaceutical preparation (Aluminium Hydroxide Gel - USP. Also, the synthesized preservatives have shown comparative and even better efficacy than the existing parabens and hence they have potential for use in pharmaceutical preparations.

Synthesis, characterization and stability of Cr(III) and Fe(III) hydroxides

Energy Technology Data Exchange (ETDEWEB)

Papassiopi, N.; Vaxevanidou, K.; Christou, C.; Karagianni, E.; Antipas, G.S.E., E-mail: gantipas@metal.ntua.gr

2014-01-15

Highlights: • Fe(III)–Cr(III) hydroxides enhance groundwater quality better than pure Cr(III) compounds. • Crystalline Cr(OH){sub 3}·3H{sub 2}O was unstable, with a solubility higher than 50 μg/l. • Amorphous Cr(OH){sub 3}(am) was stable with a solubility lower than 50 μg/l in the range 5.7 < pH < 11. • For mixed Fe{sub 0.75}Cr{sub 0.25}(OH){sub 3}, the stability region was extended to 4.8 < pH < 13.5. -- Abstract: Chromium is a common contaminant of soils and aquifers and constitutes a major environmental problem. In nature, chromium usually exists in the form of two oxidation states, trivalent, Cr(III), which is relatively innocuous for biota and for the aquatic environment, and hexavalent, Cr(VI) which is toxic, carcinogenic and very soluble. Accordingly, the majority of wastewater and groundwater treatment technologies, include a stage where Cr(VI) is reduced to Cr(III), in order to remove chromium from the aqueous phase and bind the element in the form of environmentally stable solid compounds. In the absence of iron the final product is typically of the form Cr(OH){sub 3}·xH{sub 2}O whereas in the presence of iron the precipitate is a mixed Fe{sub (1−x)}Cr{sub x}(OH){sub 3} phase. In this study, we report on the synthesis, characterisation and stability of mixed (Fe{sub x},Cr{sub 1−x})(OH){sub 3} hydroxides as compared to the stability of Cr(OH){sub 3}. We established that the plain Cr(III) hydroxide, abiding to the approximate molecular formula Cr(OH){sub 3}·3H{sub 2}O, was crystalline, highly soluble, i.e. unstable, with a tendency to transform into the stable amorphous hydroxide Cr(OH){sub 3}(am) phase. Mixed Fe{sub 0.75}Cr{sub 0.25}(OH){sub 3} hydroxides were found to be of the ferrihydrite structure, Fe(OH){sub 3}, and we correlated their solubility to that of a solid solution formed by plain ferrihydrite and the amorphous Cr(III) hydroxide. Both our experimental results and thermodynamic calculations indicated that mixed Fe

In Situ Chemical Oxidation Using Potassium Permanganate. Innovative Technology Summary Report

International Nuclear Information System (INIS)

1999-01-01

The In Situ Chemical Oxidation Using Potassium Permanganate [KMnO4] treats soils or groundwater contaminated with a range of organic chemicals, including trichlorethylene. Potential application to metal and radionuclide contaminants, including oxidation/immobilization of uranium, is being investigated. This technology is designed for use with efficient delivery systems, such as the Multi-Point Injection System and Deep Soil Mixing, to treat contaminants in low permeability soils

Preparation and inhibition properties of molybdate intercalated ZnAlCe layered double hydroxide

Energy Technology Data Exchange (ETDEWEB)

Yan, Huajie; Wang, Jihui, E-mail: jhwang@tju.edu.cn; Zhang, Yu; Hu, Wenbin

2016-09-05

ZnAlCe layered double hydroxide intercalated by molybdate (ZnAlCe−MoO{sub 4} LDH) was successfully synthesized by using co-precipitation method, and the morphology, structure of ZnAlCe−MoO{sub 4} LDH were observed and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR) techniques. The inhibition behavior of ZnAlCe−MoO{sub 4} LDH for Q235 steel in 3.5%NaCl solution was determined by polarization curves, electrochemical impedance spectroscopy (EIS), inductively coupled plasma mass spectrometer (ICP-MS) and X-ray photoelectron spectrometer (XPS) methods. The results shows that the synthesized ZnAlCe−MoO{sub 4} LDH has a lamellar structure with a particle size of 0.1–2.0 μm, an average thickness of 30 nm, and a basal plane spacing of 0.898 nm. Compared with the addition of ZnAl layered double hydroxide intercalated by nitrate (ZnAl−NO{sub 3} LDH) and ZnAl layered double hydroxide intercalated by molybdate (ZnAl−MoO{sub 4} LDH) in 3.5% NaCl solution, Q235 steel in 3.5%NaCl + ZnAlCe−MoO{sub 4} LDH solution has a lower corrosion current density, larger polarization resistance and a higher inhibition efficiency. The addition of ZnAlCe−MoO{sub 4} LDH will reduce the chloride concentration in 3.5% NaCl solution by the anion exchanged with molybdate, and improve the corrosion resistance of Q235 steel owing to the formation of passive film with the composition of ferrous or iron molybdate and deposition film with zinc and cerium hydroxides. - Highlights: • ZnAlCe−MoO{sub 4} LDH compound was successfully synthesized by co-precipitation method. • ZnAlCe−MoO{sub 4} LDH has a better inhibition effect to Q235 steel in 3.5%NaCl solution. • The Cl{sup −} ions in solution was partially exchanged with MoO{sub 4}{sup 2−} ions in host layers. • The passive film and deposition film were formed by the release of LDH compound.

Zinc-stearate-layered hydroxide nanohybrid material as a precursor to produce carbon nanoparticles

International Nuclear Information System (INIS)

Ghotbi, Mohammad Yeganeh; Bagheri, Narjes; Sadrnezhaad, S.K.

2011-01-01

Research highlights: → In this work, a new organic-clay nanohybrid material, in which the organic moiety is intercalated between the inorganic layers, was synthesized using stearate anion as a guest and zinc hydroxide nitrate as an inorganic layered host by ion-exchange technique. Carbon nanoparticles were obtained by heat treating of the nanohybrid material, zinc-stearate-layered hydroxide. The proposed method is very simple, the chemicals used in the synthesis are cheap and the manner is economic and suitable for a large scale production of nano-sized carbon nanoparticles. - Abstract: Zinc-stearate-layered hydroxide nanohybrid was prepared using stearate anion as an organic guest, and zinc layered hydroxide nitrate, as a layered inorganic host by the ion-exchange method. Powder X-ray diffraction patterns and Fourier transform infrared results indicated that the stearate anion was actually intercalated into the interlayer of zinc layered hydroxide nitrate and confirmed the formation of the host-guest nanohybrid material. Also, surface properties data showed that the intercalation process has changed the porosity for the as-prepared nanohybrid material in comparison with that of the parent material, zinc hydroxide nitrate. The nanohybrid material was heat-treated at 600 deg. C under argon atmosphere. Stearate anion was chosen as a carbonaceous reservoir in the nanohybrid to produce carbon nanoparticles after heat-treating of the nanohybrid and subsequently acid washing process.

75 FR 28608 - Calcium Hydroxide; Receipt of Application for Emergency Exemption, Solicitation of Public Comment

Science.gov (United States)

2010-05-21

... ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-OPP-2010-0411; FRL-8826-7] Calcium Hydroxide; Receipt of... Department of Agriculture to use the pesticide calcium hydroxide (CAS No. 1305-62-0) to treat up to 1,000... Agriculture has requested the Administrator to issue a quarantine exemption for the use of calcium hydroxide...

Efficacy and Safety of Photon Induced Photoacoustic Streaming for Removal of Calcium Hydroxide in Endodontic Treatment

Directory of Open Access Journals (Sweden)

Markus Laky

2018-01-01

Full Text Available Calcium hydroxide removal from the root canal by photon induced photoacoustic streaming (PIPS compared to needle irrigation and irrigation using sonic activation was investigated. Additionally, safety issues regarding apical extrusion were addressed. In endodontic treatment temporary intracanal medication like calcium hydroxide should be completely removed for long term success. For analysis, 60 artificial teeth were prepared, filled with calcium hydroxide, and divided into four groups. The teeth were assigned to needle irrigation, irrigation using a sonic device, PIPS with a lower energy setting (10 mJ, 15 Hz, or PIPS with a higher energy setting (25 mJ/40 Hz. For comparison the weight of each tooth was measured before and after calcium hydroxide incorporation, as well as after removing calcium hydroxide using the four different methods. Regarding safety issues another 24 samples were filled with stained calcium hydroxide and embedded in 0.4% agarose gel. Color changes in the agarose gel due to apical extrusion were digitally analysed using Photoshop. No significant differences were found for calcium hydroxide removal between the two laser groups. Sonic assisted removal and needle irrigation resulted in significant less calcium hydroxide removal than both laser groups, with significantly more calcium hydroxide removal in the ultrasonic group than in the needle irrigation group. For apical extrusion the higher laser (25 mJ/40 Hz group resulted in significant higher color changes of the periapical gel than all other groups. PIPS with the setting of 10 mJ/15 Hz achieved almost complete removal of calcium hydroxide without increasing apical extrusion of the irrigation solution.

Characteristics of Cement Solidification of Metal Hydroxide Waste

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Dae-Seo Koo

2017-02-01

Full Text Available To perform the permanent disposal of metal hydroxide waste from electro-kinetic decontamination, it is necessary to secure the technology for its solidification. The integrity tests on the fabricated solidification should also meet the criteria of the Korea Radioactive Waste Agency. We carried out the solidification of metal hydroxide waste using cement solidification. The integrity tests such as the compressive strength, immersion, leach, and irradiation tests on the fabricated cement solidifications were performed. It was also confirmed that these requirements of the criteria of Korea Radioactive Waste Agency on these cement solidifications were met. The microstructures of all the cement solidifications were analyzed and discussed.

Characteristics of cement solidification of metal hydroxide waste

Energy Technology Data Exchange (ETDEWEB)

Koo, Dae Seo; Sung, Hyun Hee; Kim, Seung Soo; Kim, Gye Nam; Choi, Jong Won [Dept. of Decontemination Decommission Technology Development, Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2017-02-15

To perform the permanent disposal of metal hydroxide waste from electro-kinetic decontamination, it is necessary to secure the technology for its solidification. The integrity tests on the fabricated solidification should also meet the criteria of the Korea Radioactive Waste Agency. We carried out the solidification of metal hydroxide waste using cement solidification. The integrity tests such as the compressive strength, immersion, leach, and irradiation tests on the fabricated cement solidifications were performed. It was also confirmed that these requirements of the criteria of Korea Radioactive Waste Agency on these cement solidifications were met. The microstructures of all the cement solidifications were analyzed and discussed.

Aluminium hydroxide-the carrier for catalysts coating

International Nuclear Information System (INIS)

Normatov, I.Sh.; Mirsaidov, U.M.

2003-01-01

At present time several methods of receiving aluminium hydroxide are exist. But all they differ by much staging of process connected with preliminary receiving of intermediate compounds, with application of expensive metallic aluminium

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-.

Layered double hydroxides

DEFF Research Database (Denmark)

López Rayo, Sandra; Imran, Ahmad; Hansen, Hans Chr. Bruun

2017-01-01

A novel zinc (Zn) fertilizer concept based on Zn doped layered double hydroxides (Zn-doped Mg-Fe-LDHs) has been investigated. Zn-doped Mg-Fe-LDHs were synthetized, their chemical composition was analyzed and their nutrient release was studied in buffered solutions with different pH values. Uptake...... equation showing maximum release at pH 5.2, reaching approximately 45% of the total Zn content. The Zn concentrations in the plants receiving the LDHs were between 2- and 9.5-fold higher than those in plants without Zn addition. A positive effect of the LDHs was also found in soil. This work documents...

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.

Antimicrobial effect of calcium hydroxide as endo intracanal dressing on Streptococcus viridans

Directory of Open Access Journals (Sweden)

Nanik Zubaidah

2008-03-01

Full Text Available Calcium hydroxide had been used as the intra-canal dressing in endodontic treatment due to its high alkaline and antimicrobial capacity. It can also dissolve the necrotic tissue, prevent dental root resorbtion and regenerate a new hard tissue. The aim of this study was to determine the concentration of calcium hydroxide which had the highest antimicrobial effect on Streptococcus viridans. Samples were divided into 5 groups; each group consisted of 8 samples with different concentration of calcium hydroxide. Group I: 50%, group II: 55, Group III: 60%, Group IV: 65%, Group V: 70%. The antimicrobial testing was performed using diffusion method against Streptococcus viridans. The result of susceptibility test was showed by the inhibition zone diameter which measured with caliper (in millimeter. We analyzed the data using One-Way ANOVA test with significant difference 0.05 and subsequently LSD test. The study showed that calcium hydroxide with concentration 60% has the highest antimicrobial effect.

Parametric Effect of Sodium Hydroxide and Sodium Carbonate on the Potency of a Degreaser

OpenAIRE

Babatope Abimbola Olufemi

2016-01-01

Experimental and statistical analysis was carried out on the comparative effect of sodium hydroxide and sodium carbonate on the potency of a laboratory produced degreaser in this work. The materials used include; octadecyl benzene sulphonic acid, sodium hydroxide, sodium carbonate, sodium metasilicate, carboxyl methyl cellulose (C.M.C), formadelhyde, perfume, colourant and distilled water. Different samples of degreaser were produced with varying composition of sodium hydroxide and sodium car...

The effect of magnesium hydroxide, hydromagnesite and layered double hydroxide on the heat stability and fire performance of plasticized poly(vinyl chloride)

CSIR Research Space (South Africa)

Molefe, DM

2015-09-01

Full Text Available . The other samples contained, in addition, minor amounts of iron, manganese nickel and calcium as impurities. Table 2. XRF composition analysis data of samples roasted at 1000 C Concentration, wt.% SiO2 Al2O3 Fe2O3 MnO MgO CaO NiO MgAl-LDH 1.59 36.85 0... additives aluminium trihydrate, magnesium hydroxide (MH), hydromagnesite (HM) and layered double hydroxide (LDH) have utility as endothermic flame retardants and smoke suppressants for PVC as well as other polymers (10-14). Their flame retardant action...

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.

TiO2 Nanowire Networks Prepared by Titanium Corrosion and Their Application to Bendable Dye-Sensitized Solar Cells

Directory of Open Access Journals (Sweden)

Saera Jin

2017-10-01

Full Text Available TiO2 nanowire networks were prepared, using the corrosion of Ti foils in alkaline (potassium hydroxide, KOH solution at different temperatures, and then a further ion-exchange process. The prepared nanostructures were characterized by field emission scanning electron microscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy. The wet corroded foils were utilized as the photoanodes of bendable dye-sensitized solar cells (DSSCs, which exhibited a power conversion efficiency of 1.11% under back illumination.

Effects of channel blocking on information transmission and energy efficiency in squid giant axons.

Science.gov (United States)

Liu, Yujiang; Yue, Yuan; Yu, Yuguo; Liu, Liwei; Yu, Lianchun

2018-04-01

Action potentials are the information carriers of neural systems. The generation of action potentials involves the cooperative opening and closing of sodium and potassium channels. This process is metabolically expensive because the ions flowing through open channels need to be restored to maintain concentration gradients of these ions. Toxins like tetraethylammonium can block working ion channels, thus affecting the function and energy cost of neurons. In this paper, by computer simulation of the Hodgkin-Huxley neuron model, we studied the effects of channel blocking with toxins on the information transmission and energy efficiency in squid giant axons. We found that gradually blocking sodium channels will sequentially maximize the information transmission and energy efficiency of the axons, whereas moderate blocking of potassium channels will have little impact on the information transmission and will decrease the energy efficiency. Heavy blocking of potassium channels will cause self-sustained oscillation of membrane potentials. Simultaneously blocking sodium and potassium channels with the same ratio increases both information transmission and energy efficiency. Our results are in line with previous studies suggesting that information processing capacity and energy efficiency can be maximized by regulating the number of active ion channels, and this indicates a viable avenue for future experimentation.

Improvement of the process for electrochemical impregnation of nickel hydroxide electrodes

Science.gov (United States)

Comtat, M.; Lafage, B.; Leonardi, J.

1986-01-01

Nickel hydroxide electrodes containing 11g/dsqm hydroxide, with capacities of 3.6 to 3.8 Ah/dsqm were prepared at 353 K by electrochemical impregnation. The reproducibility of the results is obtained by readjusting the pH before each preparation. The control of each electrode is done during two cycles of charge and discharge following the manufacture by a potential relaxation method.

Calculated solubility isotherm of a system of alkaline earth sulfates and hydroxides in water

International Nuclear Information System (INIS)

MOshinskii, A.S.; TIkomirova, K.A.

1986-01-01

Tis paper examines the calculation of the isothermal solubility diagram of a system of alkaline earth sulfates and hydroxides in water which makes it possible to substantiate, to a considerable extent, the natural physicochemical mineralization of natural waters, in particular water from geochemical sources. The present paper investigates the solubility of the equilibrium solid phases of a system of alkaline earth sulfates and hydroxides in water. A projection is shown of the composition prism of the quinary reciprocal system with demarcation of the crystallization areas of each sulfate and hydroxide of the component subsystems. The computational formulas for calculating solubility were derived from the solubility product principle, with allowance for ion activity coefficients in saturated hydroxide solutions

Mg/Al Ordering in Layered Double Hydroxides Revealed by Multinuclear NMR Spectroscopy

DEFF Research Database (Denmark)

Nielsen, Ulla Gro; Grey, Clare P.; Sideris, Paul J.

2008-01-01

The anion- exchange ability of layered double hydroxides ( LDHs) has been exploited to create materials for use in catalysis, drug delivery, and environmental remediation. The specific cation arrangements in the hydroxide layers of hydrotalcite- like LDHs, of general formula Mg1-x2+Alx3+OH2(Anion...

Analysis of Zr++++ dan ZrO++ cations through their Hydroxide precipitate with thermal differential analysis method

International Nuclear Information System (INIS)

Simbolon, Sahat; Ratmi-Herlani

1996-01-01

Hydroxide of zirconyl and zirconium, made by reacting zirconium and zirconyl solution with NH 4 OH 25 % solution, were analysed by thermal differential analysis (TDA). It was also done TDA method for hydroxide of zirconyl and zirconium, made by reacting zirconyl chloride and zirconium chloride solid with NH 4 OH 25 % solution directly. It was found that TDA of hydroxide precipitate made through solution had a clear TDA counter, meanwhile TDA thermogram of hydroxide precipitate made by direct adding NH 4 OH 25 % solution to zirconyl and zirconium hydroxide had no clear TDA thermogram. Precipitate Zr O(OH) 2 and Zr(OH) 4 found through solution could be differentiated each other based on their TDA thermograms

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

Bacteria encapsulated in layered double hydroxides: towards an efficient bionanohybrid for pollutant degradation.

Science.gov (United States)

Halma, Matilte; Mousty, Christine; Forano, Claude; Sancelme, Martine; Besse-Hoggan, Pascale; Prevot, Vanessa

2015-02-01

A soft chemical process was successfully used to immobilize Pseudomonas sp. strain ADP (ADP), a well-known atrazine (herbicide) degrading bacterium, within a Mg2Al-layered double hydroxide host matrix. This approach is based on a simple, quick and ecofriendly direct coprecipitation of metal salts in the presence of a colloidal suspension of bacteria in water. It must be stressed that by this process the mass ratio between inorganic and biological components was easily tuned ranging from 2 to 40. This ratio strongly influenced the biological activity of the bacteria towards atrazine degradation. The better results were obtained for ratios of 10 or lower, leading to an enhanced atrazine degradation rate and percentage compared to free cells. Moreover the biohybrid material maintained this biodegradative activity after four cycles of reutilization and 3 weeks storage at 4°C. The ADP@MgAl-LDH bionanohybrid materials were completely characterized by X-ray diffraction (XRD), FTIR spectroscopy, thermogravimetric analysis and scanning and transmission electronic microscopy (SEM and TEM) evidencing the successful immobilization of ADP within the inorganic matrix. This synthetic approach could be readily extended to other microbial whole-cell immobilization of interest for new developments in biotechnological systems. Copyright © 2014 Elsevier B.V. All rights reserved.

40 CFR 721.6183 - Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow alkyl amines...

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Amides, from ammonium hydroxide... Substances § 721.6183 Amides, from ammonium hydroxide - maleic anhydride polymer and hydrogenated tallow... subject to reporting. (1) The chemical substance identified as amides, from ammonium hydroxide - maleic...

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. ...

Co-precipitation and solubility studies of cesium, potassium and sodium tetraphenylborate

International Nuclear Information System (INIS)

Peterson, R.A.

2000-01-01

This report contains the results from a study requested by High Level Waste on the co-precipitation and solubility of cesium, potassium, and sodium tetraphenylborate. Co-precipitation of cesium (Cs), potassium (K), and sodium (Na) tetraphenylborate (TPB) helps determine the efficiency of reagent usage in the Small Tank Precipitation Process. This process uses NaTPB to remove cesium from waste by means of precipitation. Previous studies by McCabe suggested that if the sodium ion concentration [Na + ] increased the rate at which cesium tetraphenylborate (CsTPB) precipitates also increases. Serkiz also demonstrated that the precipitation of potassium tetraphenylborate (KTPB) in the presence of high [Na + ] (∼5M) appears to produce a mixed solid phase composed of NaTPB and KTPB together in the crystal lattice. In the crystallographic structure of these three tetraphenylborate salts (Cs,K,NaTPB), the tetraphenylborate ion dominates the size of the crystals. Also, note that the three crystals have nearly identical structures with the exception of two additional peaks in the cesium pattern. Given these similarities, TPB precipitation in the presence of Na + , Cs + and K + likely produces an impure isomorphic crystalline mixture of CsTPB, KTPB and NaTPB. The authors speculate that the primary crystalline structure resembles that of KTPB with NaTPB and CsTPB mixed throughout the crystal structure. The precipitation of NaTPB makes some of the anticipated excess tetraphenylborate relatively unavailable for precipitation of cesium. Thus, the amount of excess tetraphenylborate required to completely precipitate all of the potassium and cesium may increase significantly

Inhibition effect of calcium hydroxide point and chlorhexidine point on root canal bacteria of necrosis teeth

Directory of Open Access Journals (Sweden)

Andry Leonard Je

2006-03-01

Full Text Available Calcium Hydroxide point and Chlorhexidine point are new drugs for eliminating bacteria in the root canal. The points slowly and controly realease Calcium Hydroxide and Chlorhexidine into root canal. The purpose of the study was to determined the effectivity of Calcium hydroxide point (Calcium hydroxide plus point and Chlorhexidine point in eleminating the root canal bacteria of nescrosis teeth. In this study 14 subjects were divided into 2 groups. The first group was treated with Calcium hydroxide point and the second was treated with Chlorhexidine poin. The bacteriological sampling were measured with spectrofotometry. The Paired T Test analysis (before and after showed significant difference between the first and second group. The Independent T Test which analysed the effectivity of both groups had not showed significant difference. Although there was no significant difference in statistical test, the result of second group eliminate more bacteria than the first group. The present finding indicated that the use of Chlorhexidine point was better than Calcium hydroxide point in seven days period. The conclusion is Chlorhexidine point and Calcium hydroxide point as root canal medicament effectively eliminate root canal bacteria of necrosis teeth.

Hydrogen storage in hybrid of layered double hydroxides/reduced graphene oxide using spillover mechanism

International Nuclear Information System (INIS)

Ensafi, Ali A.; Jafari-Asl, Mehdi; Nabiyan, Afshin; Rezaei, Behzad; Dinari, Mohammad

2016-01-01

New efficient hydrogen storage hybrids were fabricated based on hydrogen spillover mechanism, including chemisorptions and dissociation of H_2 on the surface of LDH (layered double hydroxides) and diffusion of H to rGO (reduced graphene oxide). The structures and compositions of all of the hybrids (LDHs/rGO) have been verified using different methods including transmission electron microscopy, X ray diffraction spectroscopy, infrared spectroscopy and Brunauer–Emmett–Teller analysis. Then, the abilities of the LDHs/rGOs, as hydrogen spillover, were investigated by electrochemical methods. In addition, the LDHs/rGOs were decorated with palladium, using redox replacement process, and their hydrogen spillover properties were studied. The results showed that the hydrogen adsorption/desorption kinetics, hydrogen storage capacities and stabilities of Pd"#LDH/rGOs are better than Pd/rGO. Finally presence of different polymers (synthesis with monomers, 4–aminophenol, 4–aminothiophenol, o-phenylenediamine and p-phenylenediamine) at the surface of the Pd#LDH/rGOs on hydrogen storage were studied. The results showed that presence of o-phenylenediamine and p-phenylenediamine improves the kinetics of the hydrogen adsorption/desorption and increase the capacity of the hydrogen storage. - Highlights: • Efficient hydrogen storage sorbents are introduced. • The sorbents are synthesized based on hybrids of layered double hydroxide. • The compositions of all of the hybrids are verified using different methods. • Pd nanoparticles modified nanohybrids are investigated for hydrogen storage. • Presence of different polymers beside the hydrogen sorbents are investigated.

Surface structure and adsorption properties of ultrafine porous carbon fibers

International Nuclear Information System (INIS)

Song Xiaofeng; Wang Ce; Zhang Dejiang

2009-01-01

Ultrafine porous carbon fibers (UPCFs) were successfully synthesized by chemical activation of electrospun polyacrylonitrile fibers. In the current approach, potassium hydroxide was adopted as activation reagent. UPCFs were systematically evaluated by scanning electron microscope and nitrogen adsorption. The mass ratio of potassium hydroxide to preoxidized fibers, activation temperature and activation time are crucial for producing high quality UPCFs. The relationships between porous structure and process parameters are explored. UPCFs were applied as adsorbent for nitrogen monoxide to be compared with commercial porous carbon fibers.

Nanostructured Materials

Science.gov (United States)

2012-08-30

potassium hydroxide (2.088 mg) were added to a 10 mL volumetric flask. The balance of the volume to 10 mL was filled with ethanol. The contents were...water (0.27 g), and potassium hydroxide (2.088 mg) were added to a 10 mL volumetric flask. The balance of the volume to 10 mL was filled with ethanol...modification of metals, fill- ers, and composites can be prepared. Preferred reactive groups include but are not limited to silanols, siloxides, meth- acrylates

Nickel hydroxide positive electrode for alkaline rechargeable battery

Science.gov (United States)

Young, Kwo; Wang, Lixin; Mays, William; Reichman, Benjamin; Chao-Ian, Hu; Wong, Diana; Nei, Jean

2018-02-20

Certain nickel hydroxide active cathode materials for use in alkaline rechargeable batteries are capable of transferring >1.3 electrons per Ni atom under reversible electrochemical conditions. The specific capacity of the nickel hydroxide active materials is for example .gtoreq.325 mAh/g. The cathode active materials exhibit an additional discharge plateau near 0.8 V vs. a metal hydride (MH) anode. Ni in an oxidation state of less than 2, such as Ni.sup.1+, is able to participate in electrochemical reactions when using the present cathode active materials. It is possible that up to 2.3 electrons, up to 2.5 electrons or more may be transferred per Ni atom under electrochemical conditions.

Nickel hydroxide positive electrode for alkaline rechargeable battery

Science.gov (United States)

Young, Kwo; Wang, Lixin; Mays, William; Reichman, Benjamin; Chao-Ian, Hu; Wong, Diana; Nei, Jean

2018-04-03

Certain nickel hydroxide active cathode materials for use in alkaline rechargeable batteries are capable of transferring >1.3 electrons per Ni atom under reversible electrochemical conditions. The specific capacity of the nickel hydroxide active materials is for example .gtoreq.325 mAh/g. The cathode active materials exhibit an additional discharge plateau near 0.8 V vs. a metal hydride (MH) anode. Ni in an oxidation state of less than 2, such as Ni.sup.1+, is able to participate in electrochemical reactions when using the present cathode active materials. It is possible that up to 2.3 electrons, up to 2.5 electrons or more may be transferred per Ni atom under electrochemical conditions.

Novel polymeric potassium complex: Its synthesis, structural characterization, photoluminescence and electrochemical properties

Energy Technology Data Exchange (ETDEWEB)

Ceyhan, Goekhan [Chemistry Department, K.Maras Suetcue Imam University, 46100 K.Maras (Turkey); Tuemer, Mehmet, E-mail: mtumer@ksu.edu.tr [Chemistry Department, K.Maras Suetcue Imam University, 46100 K.Maras (Turkey); Koese, Muhammet; McKee, Vickie [Chemistry Department, Loughborough University, LE11 3TU Leicestershire (United Kingdom)

2012-03-15

In this paper, we obtained a novel poly(vanillinato potassium) complex (PVP) as a single crystal and characterized by analytical and spectroscopic methods. A single crystal of the PVP was obtained from the acetone solution. X-ray structural data show that crystals contain polymeric K{sup +} complex of vanillin. Each potassium ion in the polymeric structure is identical and seven-coordinate, bonded to two methoxy, two phenoxy and three aldehyde oxygen atoms from four vaniline molecules. Two aldehyde oxygen atoms are bridging between potassium ions. It crystallizes in the monoclinic system, space group P2{sub 1}/c, with lattice parameters a=9.6215(10) A, b=17.4139(19) A, c=9.6119(10) A, {beta}=100.457(2) Degree-Sign and Z=4. Thermal properties of the PVP were investigated by TGA, DTA and DSC methods. The electrochemical properties of the complex were studied in different solvents and at various scan rates. The luminescence properties of the complex in different solvents and at different pH values have been investigated. The results show that the complex exhibits more efficient luminescence property in CH{sub 3}CN and n-butanol. - Highlights: Black-Right-Pointing-Pointer Novel polymeric potassium complex was prepared and fully characterized. Black-Right-Pointing-Pointer X-ray crystal structure of complex was reported. Black-Right-Pointing-Pointer Electrochemical properties of compound were investigated. Black-Right-Pointing-Pointer Thermal and DSC measurements of complex were examined.

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.

Multifunctional gold coated rare-earth hydroxide fluoride nanotubes for simultaneous wastewater purification and quantitative pollutant determination

International Nuclear Information System (INIS)

Zhang, Da-Quan; Sun, Tian-Ying; Yu, Xue-Feng; Jia, Yue; Chen, Ming; Wang, Jia-Hong; Huang, Hao; Chu, Paul K.

2014-01-01

Highlights: • The morphology and properties of Ce-doped yttrium hydroxide fluoride nanotubes (YHF:Ce NTs) were investigated. • YHF:Ce NTs were conjugated with Au nanoparticles to produce Au-YHF:Ce nanocomposites. • Au-YHF:Ce NTs showed excellent capability and efficiency in removing Congo red from solutions. • Au-YHF:Ce NTs were utilized to determine the concentration of Congo red based on SERS. - Abstract: Ce-doped yttrium hydroxide fluoride nanotubes (YHF:Ce NTs) with large surface area are synthesized and conjugated with Au nanoparticles (NPs) to produce Au-YHF:Ce nanocomposites. The Au-YHF:Ce NTs have a hollow structure, rough surface, polymer coating, and good surface-enhanced Raman spectroscopy (SERS) properties. They are applied to wastewater treatment to remove Congo red as a typical pollutant. The materials not only remove pollutants rapidly from the wastewater, but also detect trace amounts of the pollutants quantitatively. The multifunctional Au-YHF:Ce NTs have commercial potential as nano-absorbents and nano-detectors in water treatment and environmental monitoring

Multifunctional gold coated rare-earth hydroxide fluoride nanotubes for simultaneous wastewater purification and quantitative pollutant determination

Energy Technology Data Exchange (ETDEWEB)

Zhang, Da-Quan; Sun, Tian-Ying [Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Yu, Xue-Feng, E-mail: yxf@whu.edu.cn [Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China); Jia, Yue; Chen, Ming; Wang, Jia-Hong [Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Huang, Hao [Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education, School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China); Chu, Paul K., E-mail: paul.chu@cityu.edu.hk [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China)

2014-04-01

Highlights: • The morphology and properties of Ce-doped yttrium hydroxide fluoride nanotubes (YHF:Ce NTs) were investigated. • YHF:Ce NTs were conjugated with Au nanoparticles to produce Au-YHF:Ce nanocomposites. • Au-YHF:Ce NTs showed excellent capability and efficiency in removing Congo red from solutions. • Au-YHF:Ce NTs were utilized to determine the concentration of Congo red based on SERS. - Abstract: Ce-doped yttrium hydroxide fluoride nanotubes (YHF:Ce NTs) with large surface area are synthesized and conjugated with Au nanoparticles (NPs) to produce Au-YHF:Ce nanocomposites. The Au-YHF:Ce NTs have a hollow structure, rough surface, polymer coating, and good surface-enhanced Raman spectroscopy (SERS) properties. They are applied to wastewater treatment to remove Congo red as a typical pollutant. The materials not only remove pollutants rapidly from the wastewater, but also detect trace amounts of the pollutants quantitatively. The multifunctional Au-YHF:Ce NTs have commercial potential as nano-absorbents and nano-detectors in water treatment and environmental monitoring.

Sandwich-like graphene/polypyrrole/layered double hydroxide nanowires for high-performance supercapacitors

Science.gov (United States)

Li, Xuejin; Zhang, Yu; Xing, Wei; Li, Li; Xue, Qingzhong; Yan, Zifeng

2016-11-01

Electrode design in nanoscale is considered to be ultra-important to construct a superb capacitor. Herein, a sandwich-like composite was made by combining graphene/polypyrrole (GPPY) with nickel-aluminum layered double hydroxide nanowires (NiAl-NWs) via a facile hydrothermal method. This sandwich-like architecture is promising in energy storage applications due to three unique features: (1) the conductive GPPY substrate not only effectively prevents the layered double hydroxides species from aggregating, but also considerably facilitates the electron transmission; (2) the ultrathin NiAl-NWs ensure a maximum exposure of active Ni2+, which can improve the efficiency of rapid redox reactions even at high current densities; (3) the sufficient space between anisotropic NiAl-NWs can accommodate a large volume change of the nanowires to avoid their collapse or distortion during the reduplicative redox reactions. Keeping all these unique features in mind, when the as-prepared composite was applied to supercapacitors, it presented an enhanced capacitive performance in terms of high specific capacitance (845 F g-1), excellent rate performance (67% retained at 30 A g-1), remarkable cyclic stability (92% maintained after 5000 cycles) and large energy density (40.1 Wh·Kg-1). This accomplishment in the present work inspires an innovative strategy of nanoscale electrode design for high-rate performance supercapacitor electrodes containing pseuducapacitive metal oxide.

An Efficient Composition for Bengal Lights.

Science.gov (United States)

Comet, M.; Schreyeck, L.; Fuzellier, H.

2002-01-01

Reports the discovery of an efficient base composition for making bengal lights that is obtained with potassium chlorate and thiourea. Combining this mixture with appropriate flame coloring can produce several impressive bengal lights. (DDR)

Comparative evaluation of different forms of calcium hydroxide in apexification

OpenAIRE

Subhankar Ghosh; Dibyendu Mazumdar; Pradip Kumar Ray; Bhaswar Bhattacharya

2014-01-01

Background: One out of every two children sustains a dental injury most often between 8 and 10 years of age. Majority of these teeth subsequently become non-vital and most often with immature apex. Management of these teeth is an enormous challenge for lack of apical stop. Calcium hydroxide in various formulations has maximum literature support in favor of "successful apexification or induced apical closure." Aim: The aim of the following study is to determine the efficacy of calcium hydroxid...

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...

Sodium-potassium synergism in Theobroma cacao: stimulation of photosynthesis, water-use efficiency and mineral nutrition.

Science.gov (United States)

Gattward, James N; Almeida, Alex-Alan F; Souza, José O; Gomes, Fábio P; Kronzucker, Herbert J

2012-11-01

In ecological setting, sodium (Na(+)) can be beneficial or toxic, depending on plant species and the Na(+) level in the soil. While its effects are more frequently studied at high saline levels, Na(+) has also been shown to be of potential benefit to some species at lower levels of supply, especially in C4 species. Here, clonal plants of the major tropical C3 crop Theobroma cacao (cacao) were grown in soil where potassium (K(+)) was partially replaced (at six levels, up to 50% replacement) by Na(+), at two concentrations (2.5 and 4.0 mmol(c) dm(-3)). At both concentrations, net photosynthesis per unit leaf area (A) increased more than twofold with increasing substitution of K(+) by Na(+). Concomitantly, instantaneous (A/E) and intrinsic (A/g(s)) water-use efficiency (WUE) more than doubled. Stomatal conductance (g(s)) and transpiration rate (E) exhibited a decline at 2.5 mmol dm(-3), but remained unchanged at 4 mmol dm(-3). Leaf nitrogen content was not impacted by Na(+) supplementation, whereas sulfur (S), calcium (Ca(2+)), magnesium (Mg(2+)) and zinc (Zn(2+)) contents were maximized at 2.5 mmol dm(-3) and intermediate (30-40%) replacement levels. Leaf K(+) did not decline significantly. In contrast, leaf Na(+) content increased steadily. The resultant elevated Na(+)/K(+) ratios in tissue correlated with increased, not decreased, plant performance. The results show that Na(+) can partially replace K(+) in the nutrition of clonal cacao, with significant beneficial effects on photosynthesis, WUE and mineral nutrition in this major perennial C3 crop. Copyright © Physiologia Plantarum 2012.

Evaluation of Extraction and Degradation Methods to Obtain Chickpeasaponin B1 from Chickpea (Cicer arietinum L.

Directory of Open Access Journals (Sweden)

Kun Cheng

2017-02-01

Full Text Available The objective of this research is to implement extraction and degradation methods for the obtainment of 3-O-[α-l-rhamnopyranosyl-(1→2-β-d-galactopyranosyl] soyasapogenol B (chickpeasaponin B1 from chickpea. The effects of microwave-assisted extraction (MAE processing parameters—such as ethanol concentration, solvent/solid ratio, extraction temperature, microwave irradiation power, and irradiation time—were evaluated. Using 1g of material with 8 mL of 70% aqueous ethanol and an extraction time of 10 min at 70 °C under irradiation power 400W provided optimal extraction conditions. Compared with the conventional extraction techniques, including heat reflux extraction (HRE, Soxhlet extraction (SE, and ultrasonic extraction (UE, MAE produced higher extraction efficiency under a lower extraction time. DDMP (2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one saponin can be degraded to structurally stable saponin B by the loss of its DDMP group. The influence of pH and the concentration of potassium hydroxide on transformation efficiency of the target compound was investigated. A solution of 0.25 M potassium hydroxide in 75% aqueous ethanol was suitable for converting the corresponding DDMP saponins of chickpeasaponin B1. The implementation by the combining MAE technique and alkaline hydrolysis method for preparing chickpeasaponin B1 provides a convenient technology for future applications.

Evaluation of Extraction and Degradation Methods to Obtain Chickpeasaponin B1 from Chickpea (Cicer arietinum L.).

Science.gov (United States)

Cheng, Kun; Gao, Hua; Wang, Rong-Rong; Liu, Yang; Hou, Yu-Xue; Liu, Xiao-Hong; Liu, Kun; Wang, Wei

2017-02-21

The objective of this research is to implement extraction and degradation methods for the obtainment of 3- O -[α-l-rhamnopyranosyl-(1→2)-β-d-galactopyranosyl] soyasapogenol B (chickpeasaponin B1) from chickpea. The effects of microwave-assisted extraction (MAE) processing parameters-such as ethanol concentration, solvent/solid ratio, extraction temperature, microwave irradiation power, and irradiation time-were evaluated. Using 1g of material with 8 mL of 70% aqueous ethanol and an extraction time of 10 min at 70 °C under irradiation power 400W provided optimal extraction conditions. Compared with the conventional extraction techniques, including heat reflux extraction (HRE), Soxhlet extraction (SE), and ultrasonic extraction (UE), MAE produced higher extraction efficiency under a lower extraction time. DDMP (2,3-dihydro-2,5-dihydroxy-6-methyl-4 H -pyran-4-one) saponin can be degraded to structurally stable saponin B by the loss of its DDMP group. The influence of pH and the concentration of potassium hydroxide on transformation efficiency of the target compound was investigated. A solution of 0.25 M potassium hydroxide in 75% aqueous ethanol was suitable for converting the corresponding DDMP saponins of chickpeasaponin B1. The implementation by the combining MAE technique and alkaline hydrolysis method for preparing chickpeasaponin B1 provides a convenient technology for future applications.

Doping magnesium hydroxide with sodium nitrate: a new approach to tune the dehydration reactivity of heat-storage materials.

Science.gov (United States)

Shkatulov, Alexandr; Krieger, Tamara; Zaikovskii, Vladimir; Chesalov, Yurii; Aristov, Yuri

2014-11-26

Thermochemical energy storage (TES) provides a challenging approach for improving the efficiency of various energy systems. Magnesium hydroxide, Mg(OH)2, is known as a suitable material for TES at temperature T>300 °C. In this work, the thermal decomposition of Mg(OH)2 in the absence and presence of sodium nitrate (NaNO3) is investigated to adapt this material for TES at T300 °C in vapor atmosphere) than a pure Mg(OH)2; (3) the morphology of the dehydration product (MgO) dramatically changes. Differential scanning calorimetry, high-resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and vibrational spectroscopy (IR and Raman) are used to study the observed effects and to elucidate possible ways the NaNO3 influences the Mg(OH)2 dehydration and morphology of the dehydration product. The mechanism involving a chemical interaction between the salt and the hydroxide accompanied by nitrate embedding into brucite layers is discussed.

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.

Thermal analysis of iron hydroxide microspheres

International Nuclear Information System (INIS)

Turcanu, C.N.; Cornescu, M.

1979-03-01

The thermal treatment is an important step in the preparative technology of the iron oxids microspheres with well established mechanical, physical and chemical characteristics. The first indications on the heating procedure have been obtained from the thermal analysis on iron hydroxide microspheres prepared by the support precipitation and internal gelification methods. (author)

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.

Clinical effect of calcium hydroxide paste combined with triple antibiotic paste on root canal disinfection

Directory of Open Access Journals (Sweden)

Chen QU

2014-03-01

Full Text Available Objective　To compare the efficacy in disinfection and pain control of calcium hydroxide paste and triple antibiotic paste (ornidazole, ciprofloxacin and minocycline used individually or jointly for root canal disinfection. Methods　Two hundred and thirty-five patients with chronic apical periodontitis (235 teeth were involved in the present study and divided into 2 groups: fistula group (n=118 and no fistula group (n=117. Each group was then randomly divided into 4 subgroups: calcium hydroxide paste group, triple antibiotic paste group, calcium hydroxide + triple antibiotic paste group, and camphor phenol group. After regular root canal preparation, root canals of patients in 4 groups were filled with tiny paper ends impregnated with fore 4 different drugs respectively. Visual analogue scales (VAS of pain were given to the patients with a guide for filling the scale. One week later, both the data of the scales and the effects of root canal disinfection were recorded and analyzed. Results　Seven days after treatment, the clinical efficacy of calcium hydroxide paste, triple antibiotic paste and calcium hydroxide + triple antibiotic paste was similar (P>0.05 either in fistula group or in no fistula group, but all better than that of camphor phenol (P<0.05. VAS score analysis showed that, at least on the first 3 days after sealing medicine in the root canal, calcium hydroxide + triple antibiotic paste achieved better result of pain control than the other three groups (P<0.05 no matter with or without fistula. Conclusions 　Calcium hydroxide paste, triple antibiotic paste, calcium hydroxide + triple antibiotic paste are effective in treatment of chronic apical periodontitis whether with or without fistula. However, the combined use of calcium hydroxide and three antibiotic pastes is better for controlling the pain after root canal preparation than other treatments, which is therefore worthy of clinical application. DOI: 10.11855/j.issn.0577-7402.2014.02.12

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.)

Relation of lifetime to surface passivation for atomic-layer-deposited Al2O3 on crystalline silicon solar cell

International Nuclear Information System (INIS)

Cho, Young Joon; Song, Hee Eun; Chang, Hyo Sik

2015-01-01

Highlights: • We investigated the relation of potassium contamination on Si solar wafer to lifetime. • We deposited Al 2 O 3 layer by atomic layer deposition (ALD) on Si solar wafer after several cleaning process. • Potassium can be left on Si surface by incomplete cleaning process and degrade the Al 2 O 3 passivation quality. - Abstract: We investigated the relation of potassium contamination on a crystalline silicon (c-Si) surface after potassium hydroxide (KOH) etching to the lifetime of the c-Si solar cell. Alkaline solution was employed for saw damage removal (SDR), texturing, and planarization of a textured c-Si solar wafer prior to atomic layer deposition (ALD) Al 2 O 3 growth. In the solar-cell manufacturing process, ALD Al 2 O 3 passivation is utilized to obtain higher conversion efficiency. ALD Al 2 O 3 shows excellent surface passivation, though minority carrier lifetime varies with cleaning conditions. In the present study, we investigated the relation of potassium contamination to lifetime in solar-cell processing. The results showed that the potassium-contaminated samples, due to incomplete cleaning of KOH, had a short lifetime, thus establishing that residual potassium can degrade Al 2 O 3 surface passivation

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 ...

Thermodynamic properties of beryllium hydroxide

International Nuclear Information System (INIS)

Baur, A.; Lecocq, A.

1964-01-01

The study of the hydro-thermal decomposition of beryllium hydroxide has made it possible to determine the free energy of formation and the entropy. The results obtained are in good agreement with the theoretical values calculated from the solubility product of this substance. They give furthermore the possibility of acquiring a better understanding of the BeO-H 2 O-Be (OH) 2 system between 20 and 1500 C. (authors) [fr

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 ...

Infrared spectra of phosphate sorbed on iron hydroxide gel and the sorption products

International Nuclear Information System (INIS)

Nanzyo, M.

1986-01-01

Infrared absorption spectra of phosphate sorbed on iron hydroxide gel were obtained by applying the differential diffuse reflectance method. Absorption bands due to P-O stretching vibration were observed at 1,110 and 1,010 cm -1 at pH 12.3. With decreasing pH, these absorption bands gradually shifted to 1,100 and 1,020 cm -1 at pH 4.9. At pH 2.3, they became a broad single absorption band at 1,060 cm -1 . At pH 11 or above, the difference in the Na + adsorption between phosphated iron hydroxide gel and iron hydroxide gel was almost equal to the amount of phosphate sorption. This finding shows that phosphate was retained on the iron hydroxide gel surface as a bidentate ligand at a high pH. It was concluded that at a high pH phosphate was sorbed on iron hydroxide gel as a binuclear surface complex similar to that on goethite; the change in spectra for P-O stretching vibration with decreasing pH value was mainly caused by an increase in the fraction of amorphous iron phosphate; at pH 2.3, the phosphate sorption product consisted of amorphous iron phosphate. (author)

Structure of bayerite-based lithium-aluminum layered double hydroxides (LDHs): observation of monoclinic symmetry.

Science.gov (United States)

Britto, Sylvia; Kamath, P Vishnu

2009-12-21

The double hydroxides of Li with Al, obtained by the imbibition of Li salts into bayerite and gibbsite-Al(OH)(3), are not different polytypes of the same symmetry but actually crystallize in two different symmetries. The bayerite-derived double hydroxides crystallize with monoclinic symmetry, while the gibbsite-derived hydroxides crystallize with hexagonal symmetry. Successive metal hydroxide layers in the bayerite-derived LDHs are translated by the vector ( approximately -1/3, 0, 1) with respect to each other. The exigency of hydrogen bonding drives the intercalated Cl(-) ion to a site with 2-fold coordination, whereas the intercalated water occupies a site with 6-fold coordination having a pseudotrigonal prismatic symmetry. The nonideal nature of the interlayer sites has implications for the observed selectivity of Li-Al LDHs toward anions of different symmetries.

The role of SO{sub 4}{sup 2−} surface distribution in arsenic removal by iron oxy-hydroxides

Energy Technology Data Exchange (ETDEWEB)

Tresintsi, S. [Analytical Chemistry Laboratory, Department of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Simeonidis, K., E-mail: ksime@physics.auth.gr [Analytical Chemistry Laboratory, Department of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Department of Mechanical Engineering, University of Thessaly, 38334 Volos (Greece); Pliatsikas, N.; Vourlias, G.; Patsalas, P. [Laboratory of Applied Physics, Department of Physics, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece); Mitrakas, M. [Analytical Chemistry Laboratory, Department of Chemical Engineering, Aristotle University of Thessaloniki, 54124 Thessaloniki (Greece)

2014-05-01

This study investigates the contribution of chemisorbed SO{sub 4}{sup 2−} in improving arsenic removal properties of iron oxy-hydroxides through an ion-exchange mechanism. An analytical methodology was developed for the accurate quantification of sulfate ion (SO{sub 4}{sup 2−}) distribution onto the surface and structural compartments of iron oxy-hydroxides synthesized by FeSO{sub 4} precipitation. The procedure is based on the sequential determination of SO{sub 4}{sup 2−} presence in the diffuse and Stern layers, and the structure of these materials as defined by the sulfate-rich environments during the reaction and the variation in acidity (pH 3–12). Physically sorbed SO{sub 4}{sup 2−}, extracted in distilled water, and physically/chemically adsorbed ions on the oxy-hydroxide's surface leached by a 5 mM NaOH solution, were determined using ion chromatography. Total sulfate content was gravimetrically measured by precipitation as BaSO{sub 4}. To validate the suggested method, results were verified by X-ray photoelectron and Fourier-transformed infrared spectroscopy. Results showed that low precipitation pH-values favor the incorporation of sulfate ions into the structure and the inner double layer, while under alkaline conditions ions shift to the diffuse layer. - Graphical abstract: An analytical methodology for the accurate quantification of sulfate ions (SO{sub 4}{sup 2−}) distribution onto the diffuse layer, the Stern layer and the structure of iron oxy-hydroxides used as arsenic removal agents. - Highlights: • Quantification of sulfate ions presence in FeOOH surface compartments. • Preparation pH defines the distribution of sulfates. • XPS and FTIR verify the presence of SO{sub 4}{sup 2−} in the structure, the Stern layer the diffuse layer of FeOOH. • Chemically adsorbed sulfates control the arsenic removal efficiency of iron oxyhydroxides.

46 CFR Table 1 to Part 153 - Summary of Minimum Requirements

Science.gov (United States)

2010-10-01

... NR Open Open A, D .409, .440, .488, .908(a), (b) NA Potassium hydroxide solution, see Caustic potash solution Potassium oleate C P III NR Open Open A .409 NA Potassium thiosulfate (50% or less) C P III NR... NR Open Open NSR .236(a), (b), (c), (g), .440, .908(a), .933 NA Sodium chlorate solution (50% or less...

Clinical Survey of Successfulness of DPC with MTA and Calcium Hydroxide

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E.Yasini

2005-02-01

Full Text Available Statement of Problem: The pulp may be exposed during remove of caries or by traumatic and iatrogenicinjuries. The material used to DPC, must be biocompatible, scalable and prevent bacterial leakage.Furthermore, it is better to stimulate dentinogenesis. Calcium hydroxide is most usual material for DPC. But itcannot provide a suitablcbiologic seal. Mineral irioxide aggregate (MTA is also a suitable material for DPC.Purpose: The aim of this study was to compare the clinical success of DPC done with MTA or calciumhydroxide cement.Materials and Methods: In this study eighteen posterior teeth without previous spontaneous pain thatinvolved mechanicaly exposure was randomly selected and capped with MTA or calcium hydroxide. These teeth were evaluated by clinical vitality test and radiograph after 3 and 12 months, and patients werequestioned about irritative or spontancus pain in this period. Statistical analysis was carried out by Usher exacttest (a-0.05.Results: This study showed that in calcium hydroxid groud three had irreversible pulpitis and two teeth had symptom and signs of reversible pulpitis. While, In MTA group all cases were normaL and no clinical sign was evident.Conclusion: MTA exhibited better results than calcium hydroxide cement for the capping of the pulp in human

Potassium acceptor doping of ZnO crystals

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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.

Biodiesel Production from Chlorella protothecoides Oil by Microwave-Assisted Transesterification.

Science.gov (United States)

Gülyurt, Mustafa Ömer; Özçimen, Didem; İnan, Benan

2016-04-22

In this study, biodiesel production from microalgal oil by microwave-assisted transesterification was carried out to investigate its efficiency. Transesterification reactions were performed by using Chlorella protothecoides oil as feedstock, methanol, and potassium hydroxide as the catalyst. Methanol:oil ratio, reaction time and catalyst:oil ratio were investigated as process parameters affected methyl ester yield. 9:1 methanol/oil molar ratio, 1.5% KOH catalyst/oil ratio and 10 min were optimum values for the highest fatty acid methyl ester yield.

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

Thermodynamic modeling of phases equilibrium in aqueous systems to recover potassium chloride from natural brines

Directory of Open Access Journals (Sweden)

Ruberlan Gomes da Silva

2017-01-01

Full Text Available Chemical fertilizers, such as potassium chloride, ammonium nitrate and other chemical products like sodium hydroxide and soda ash are produced from electrolyte solutions or brines with a high content of soluble salts. Some of these products are manufactured by fractional crystallization, when several salts are separated as solid phases with high purity (>90%. Due to the large global demand for potassium fertilizers, a good knowledge about the compositions of salts and brines is helpful to design an effective process. A thermodynamic model based on Pitzer and Harvie's model was used to predict the composition of crystallized salts after water removal by forced evaporation and cooling from multicomponent solutions or brines. Initially, the salts’ solubilities in binary systems (NaCl–H2O, KCl–H2O and MgCl2–H2O and ternary system (KCl–MgCl2–H2O were calculated at 20 °C and compared with literature data. Next, the model was compared to our experimental data on the quinary system NaCl–KCl–MgCl2–CaCl2–H2O system at 20 °C. The Pitzer and Harvie's model represented well both the binary and ternary systems. Besides, for the quinary system the fit was good for brine densities up to 1350 kg/m3. The models were used to estimate the chemical composition of the solutions and salts produced by fractional crystallization and in association with material balance to respond to issues related to the production rates in a solar pond containing several salts dissolved, for instance, NaCl, KCl, MgCl2 and CaCl2.

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

Polytypic transformations during the thermal decomposition of cobalt hydroxide and cobalt hydroxynitrate

International Nuclear Information System (INIS)

Ramesh, Thimmasandra Narayan

2010-01-01

The isothermal decomposition of cobalt hydroxide and cobalt hydroxynitrate at different intervals of temperature leads to the formation of Co 3 O 4 . The phase evolution during the decomposition process was monitored using powder X-ray diffraction. The transformation of cobalt hydroxide to cobalt oxide occurs via three phase mixture while cobalt hydroxynitrate to cobalt oxide occurs through a two phase mixture. The nature of the sample and its preparation method controls the decomposition mechanism. The comparison of topotactical relationship between the precursors to the decomposed product has been reported in relation to polytypism. - Graphical abstract: Isothermal thermal decomposition studies of cobalt hydroxide and cobalt hydroxynitrate at different intervals of temperature show the metastable phase formed prior to Co 3 O 4 phase.

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

Automated solid-phase extraction of phenolic acids using layered double hydroxide-alumina-polymer disks.

Science.gov (United States)

Ghani, Milad; Palomino Cabello, Carlos; Saraji, Mohammad; Manuel Estela, Jose; Cerdà, Víctor; Turnes Palomino, Gemma; Maya, Fernando

2018-01-26

The application of layered double hydroxide-Al 2 O 3 -polymer mixed-matrix disks for solid-phase extraction is reported for the first time. Al 2 O 3 is embedded in a polymer matrix followed by an in situ metal-exchange process to obtain a layered double hydroxide-Al 2 O 3 -polymer mixed-matrix disk with excellent flow-through properties. The extraction performance of the prepared disks is evaluated as a proof of concept for the automated extraction using sequential injection analysis of organic acids (p-hydroxybenzoic acid, 3,4-dihydroxybenzoic acid, gallic acid) following an anion-exchange mechanism. After the solid-phase extraction, phenolic acids were quantified by reversed-phase high-performance liquid chromatography with diode-array detection using a core-shell silica-C18 stationary phase and isocratic elution (acetonitrile/0.5% acetic acid in pure water, 5:95, v/v). High sensitivity and reproducibility were obtained with limits of detection in the range of 0.12-0.25 μg/L (sample volume, 4 mL), and relative standard deviations between 2.9 and 3.4% (10 μg/L, n = 6). Enrichment factors of 34-39 were obtained. Layered double hydroxide-Al 2 O 3 -polymer mixed-matrix disks had an average lifetime of 50 extractions. Analyte recoveries ranged from 93 to 96% for grape juice and nonalcoholic beer samples. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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.

Growth of uranyl hydroxide nanowires and nanotubes with electrodeposition method

International Nuclear Information System (INIS)

Wang Lin; Yuan Liyong; Chai Zhifang; Shi Weiqun

2013-01-01

Actinides nanomaterials have great potential applications in fabrication of novel nuclear fuel and spent fuel reprocessing in advanced nuclear energy system. However, the relative research so far still lacks systematic investigation on the synthetic methods for actinides nanomaterials. In this work, we use track-etched membranes as hard templates to synthesize uranium based nanomaterials with novel structures by electrodeposition method. Through electrochemical behavior investigations and subsequent product characterizations such as energy dispersive spectrometer (EDS), fourier transform infrared spectroscopy (FTIR), the chemical composition of deposition products have been confirmed as the uranyl hydroxide. More importantly, accurate control of morphology and structures (nanowires and nanotubes) could be achieved by carefully adjusting the growth parameters such as deposition time and deposition current density. It was found that the preferred morphology of electrodeposition products is nanowire when a low current density was applied, whereas nanotubes could be formed only under conditions of high current density and the short deposition time. The mechanism for the formation of nanowires in track-etched membranes is based on the precipitation of uranyl hydroxide from uranyl nitrate solution, according to the previous researches about obtaining nanostructures of hydroxides from nitrate salt solutions. And we have concluded that the formation of nanotubes is attributed to the hydrogen bubbles generated by water electrolysis under the condition of over-potential electro-reduction. The conveying of hydrogen bubbles plays the role of dynamic template which can prevent the complete filling of uranyl hydroxide in the channels. Additionally, we transform the chemical composition of deposition products from uranyl hydroxide to triuranium octoxide by calcining them at 500 and 800 degree centigrade, respectively, and SEM results show the morphologies of nanowires and

The Effects of Aluminium Hydroxide and Magnesium Hydroxide on the Mechanical Properties of Thermoplastic Polyurethane Materials

Directory of Open Access Journals (Sweden)

Erkin Akdoğan

2015-12-01

Full Text Available Thermoplastic polyurethane materials are widely used in automotive, clothing, electrical and electronics, medical, construction, machine industry due to excellent physical and chemical properties. Thermoplastic polyurethane materials combustion and resistance to high temperature characteristics are poor. Additives and fillers are added into the polyurethane matrix to improve those properties. Particularly adding these agents as a flame retardant are affect mechanical properties of polyurethane materials. Therefore, it is important to determinate the mechanical properties of these materials. In this study, 5% by weight of the thermoplastic polyurethane material, aluminium tri hydroxide (ATH, (Al2O3 3H2O and magnesium hydroxide (MgOH, (Mg(OH2 were added. Ammonium polyphosphate (APP as an intumescent flame retardant with inorganic flame retardants were added to increase the flame resistance of produced composite structure. Tensile test, tear test, hardness and Izod impact tests were made and compared of those produced composites. As a result of experiments the addition of ATH has lowered the tensile strength and tear strength contrast to this the addition of MgOH has improved those properties. Hardness and Izod impact test results were showed that both of the additives have no negative effect.

Electrodeposition of Zn-doped {alpha}-nickel hydroxide with flower-like nanostructure for supercapacitors

Energy Technology Data Exchange (ETDEWEB)

You Zheng [Department of Precision Instruments and Mechanology, Tsinghua University, Beijing 100084 (China); Shen Kui; Wu Zhicheng [Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083 (China); Wang Xiaofeng [Department of Precision Instruments and Mechanology, Tsinghua University, Beijing 100084 (China); Kong Xianghua, E-mail: kongxh@ustb.edu.cn [Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083 (China)

2012-08-01

Zn-doped {alpha}-nickel hydroxide materials with flower-like nanostructures are synthesized by electrochemical deposition method. The samples are characterized by X-ray diffraction (XRD), field emission scanning electron microscope (SEM) and electrochemical measurements. XRD spectra indicate nickel hydroxide doped with Zn is {alpha}-Ni(OH){sub 2} with excellent crystallization. The SEM observation shows that the formation of Zn-doped Ni(OH){sub 2} includes two steps: a honeycomb-like film forms on the substrate first, then flower-like particles forms on the films. The nickel hydroxide doped with 5% Zn can maintain a maximum specific capacitance of 860 F g{sup -1}, suggesting its potential application in electrochemical capacitors.

Electrodeposition of Zn-doped α-nickel hydroxide with flower-like nanostructure for supercapacitors

Science.gov (United States)

You, Zheng; Shen, Kui; Wu, Zhicheng; Wang, Xiaofeng; Kong, Xianghua

2012-08-01

Zn-doped α-nickel hydroxide materials with flower-like nanostructures are synthesized by electrochemical deposition method. The samples are characterized by X-ray diffraction (XRD), field emission scanning electron microscope (SEM) and electrochemical measurements. XRD spectra indicate nickel hydroxide doped with Zn is α-Ni(OH)2 with excellent crystallization. The SEM observation shows that the formation of Zn-doped Ni(OH)2 includes two steps: a honeycomb-like film forms on the substrate first, then flower-like particles forms on the films. The nickel hydroxide doped with 5% Zn can maintain a maximum specific capacitance of 860 F g-1, suggesting its potential application in electrochemical capacitors.

Honeywell Modular Automation System Computer Software Documentation for the Magnesium Hydroxide Precipitation Process

International Nuclear Information System (INIS)

STUBBS, A.M.

2001-01-01

The purpose of this Computer Software Document (CSWD) is to provide configuration control of the Honeywell Modular Automation System (MAS) in use at the Plutonium Finishing Plant (PFP) for the Magnesium Hydroxide Precipitation Process in Rm 230C/234-5Z. The magnesium hydroxide process control software Rev 0 is being updated to include control programming for a second hot plate. The process control programming was performed by the system administrator. Software testing for the additional hot plate was performed per PFP Job Control Work Package 2Z-00-1703. The software testing was verified by Quality Control to comply with OSD-Z-184-00044, Magnesium Hydroxide Precipitation Process

Action of tributyltin (TBT) on the lipid content and potassium retention in the organotins degradating fungus Cunninghamella elegans.

Science.gov (United States)

Bernat, Przemysław; Słaba, Mirosława; Długoński, Jerzy

2009-09-01

The purpose of the presented paper was to study the effect of high concentrations of tributyltin (TBT) on the potassium retention and fatty acid (FA) composition of the fungus Cunninghamella elegans recognized as a very efficient TBT degrader. An increase in TBT had a strong influence on the potassium concentration in the fungus. In growth medium without TBT, the potassium content of the fungal cells was 5.8 mg K(+) g dry weight(-1). The maximum concentration of K(+) was 15.06 mg g(-1) dry weight at 30 mg l(-1) of TBT. The major FAs that characterized the tested strain were C16:0, C18:1, C18:2, C18:3 and C18:0. TBT in the concentration range 5-30 mg l(-1) strongly influenced the FA composition. In the presence of the organotin, the degree of saturation increased. It suggests that the observed changes promote an increase in the lipid ordering of the membrane by reducing its permeability and inhibiting potassium ion efflux.

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...

Growth kinetics for the precipitation of zirconium hydroxide from aqueous zirconium and tin bearing solutions by the addition of ammonium hydroxide

Energy Technology Data Exchange (ETDEWEB)

Carleson, T.E. [Idaho Univ., Moscow, ID (United States). Dept. of Chemical Engineering; Chipman, N.A. [Westinghouse Idaho Nuclear Co., Inc., Idaho Falls, ID (United States)

1989-09-11

The precipitation of zirconium hydroxide from an aqueous solution of ammonium hexafluorozirconate occurs rapidly upon addition of ammonium hydroxide. Experimental data indicate growth and nucleation rates between 0.06 and 0.28 microns/minute and around 10 {times} 107 number/L-min, respectively. Experiments with a mixed suspension mixed product removal crystallizer for concentrations of reactants of about 0.05 M ammonium hexafluorozirconate precipitating with 0.002 M ammonium hydroxide showed apparent nonlinear growth rates in some cases but not others. Batch studies indicated that growth rate dispersion is probably not present. When the AFL nonlinear model was used to fit the data, the power coefficient obtained was greater than 1, in disagreement with theory. In addition, for some of the data ``S`` shaped curves of the logarithm of the cumulative number greater than versus size were obtained. These curves can not be fit by the AFL model. A program developed at the University of Arizona was used to simulate the crystallization runs. The program results indicated that some of the nonlinear behavior may be attributed to transient conditions. Experimental data also illustrated this behavior. The effect of trace amounts of tin fluoride (0.008 M) on the nucleation and growth kinetics was also evaluated. For some residence times, the presence of tin resulted in reduced median particle diameters, higher growth rates, and lower number counts.

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 ...

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. ...

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 solubilizing bacteria-assisted phytoextraction of radiocesium on pechay plants grown in cesium contaminated Fukushima Soils

International Nuclear Information System (INIS)

Rallos, R.V.; Yokoyama, T.

2015-01-01

Increasing the efficiency of metal uptake by plants is important to achieve successful phytoremediation of metal-polluted soils. The presence of potassium solubilizing bacteria (KSB) increases the solubilization of K-containing minerals thereby enhancing the availability of potassium (K+) and other cations including radicesium (137Cs+) for plant uptake. In this study, five KSB isolates were obtained from soybean rhizosphere in Fukushima radiocesium contaminated soils. Based on biochemical and 16S rRNA gene sequence analysis, the bacteria were identified as Bacillus megaterium, Pseudomonas putida, P. frederiksbergensis, Burkholderia sabiae, and P. mandelii. The KSB isolates were evaluated for plant growth promotion, potassium (K) uptake and radiocesium phytoextraction of pechay in three different cesium-contaminated Fukushima soils. Inoculation with KSB showed beneficial effects on plant growth and increased the phytoextraction of radiocesium, with much greater magnitude in roots than in shoots. The results indicated that KSB inoculation may be essential in managing radiocesium-contaminated soils and manipulating the transfer from soils to plants.(author)

Structural Differentiation between Layered Single (Ni) and Double Metal Hydroxides (Ni–Al LDHs) Using Wavelet Transformation

Energy Technology Data Exchange (ETDEWEB)

Siebecker, Matthew G. [University of Delaware, Delaware Environmental Institute; Sparks, Donald L. [University of Delaware, Delaware Environmental Institute

2017-09-07

Layered double hydroxides (LDHs) are anionic clays important in disciplines such as environmental chemistry, geochemistry, and materials science. Developments in signal processing of extended X-ray absorption fine structure (EXAFS) data, such as wavelet transformation (WT), have been used to identify transition metals and Al present in the hydroxide sheets of LDHs. The WT plots of LDHs should be distinct from those of isostructural single metal hydroxides. However, no direct comparison of these minerals appears in the literature using WT. This work systematically analyzes a suite of Ni-rich mineral standards, including Ni–Al LDHs, single metal Ni hydroxides, and Ni-rich silicates using WT. The results illustrate that the WT plots for α-Ni(OH)2 and Ni–Al LDHs are often indistinguishable from each other, with similar two-component plots for the different mineral types. This demonstrates that the WT of the first metal shell often cannot be used to differentiate an LDH from a single metal hydroxide. Interlayer anions adsorbed to the hydroxide sheet of α-Ni(OH)2 affect the EXAFS spectra and are not visible in the FT but are clearly resolved and discrete in the WT.

Strong blue emission from zinc hydroxide carbonate nanosheets

International Nuclear Information System (INIS)

Mao, Jing; Chen, Xuemin; Ling, Tao; Du, Xiwen

2016-01-01

Zinc hydroxide carbonate (ZHC) is a typical layered salt composed of zinc hydroxide layers separated with carbonate ions and water molecules. Studies of morphology control and the constitution of functional ZHC material with intercalated ions has been widely developed. Also, ZnO can be easily obtained by anneal treatment of ZHC, and the porous structure as synthesized had great potential in gas sensors, photocatalysts and dye-sensitized solar cells. However, the optical of ZHC have rarely been investigated. In our research, a strong blue emission of ZHC is reported. The effect of growth time, annealing treatment and modification of surfactants on blue emission have been systematically studied. Combined with information of interior effect of OH groups, crystal structure and electronegativity of surfactants, a possible emission mechanism of ZHC has been proposed.