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Gut Ivo Glynne - - 2010
Benzo[b]cyclohexa-2,4-dien-1-one (4) and benzo[b]cyclohexa-2,5-dien-1-one (5), the two most stable keto tautomers of 1-naphthol (1), were generated in aqueous solution by Norrish Type II fission of 4- and 2-phenacyl-1-tetralone, respectively, and the pH-rate profiles of their enolization were measured by flash photolysis. Several isotopic exchange rates of 1 were measured in ...
Vergnoux A - - 2011
The humic substances are an abundant and important part of soil organic matter which plays many roles in ecosystems. On the other hand, forest fires are known to have a potential impact on the soil organic matter. Consequently, we chose to study the impact of forest fires on humic substances ...
Brillas Enric - - 2010
The degradation of diclofenac, a common non-steroidal anti-inflammatory drug, in aqueous medium has been studied by anodic oxidation (AO) using an undivided cell with a Pt or boron-doped diamond (BDD) anode. Operating without pH regulation, AO with Pt acidifies the solution with precipitation of its protonated form, whereas using BDD, ...
Yasaka Yoshiro - - 2010
The equilibrium for the reversible decomposition of formic acid into carbon dioxide and hydrogen is studied in the ionic liquid (IL) 1,3-dipropyl-2-methylimidazolium formate. The equilibrium is strongly favored to the formic acid side because of the strong solvation of formic acid in the IL through the strong Coulombic solute-solvent interactions. ...
Breslow Ronald - - 2010
Previous work by us, and others, has shown that the formation of amino acids on prebiotic earth with the geometric arrangement called the L configuration can be understood. Some meteorites of the carbonaceous chondritic type deliver unusual amino acids, with alpha-methyl groups, which have an excess of the L isomers. ...
Zoppi A - - 2010
One degradation phenomenon that occurs in artworks is the formation of metal oxalates on their surfaces. In order to gain insight into the inclination of pigments to produce oxalates, nine pigments including Na, Ca, Fe, Pb and Cu cations were selected to react with oxalic acid solutions at different concentrations ...
Kretlow James D JD Department of Bioengineering, Rice University, PO Box 1892, MS 142, Houston, Texas 77251-1892, - - 2010
Stimulus responsive materials hold great promise in biological applications as they can react to changes in physiological stimuli to produce a desired effect. Stimulus responsive macromers designed to respond to temperature changes at or around 37 degrees C and the presence of divalent cations were synthesized from N-isopropylacrylamide, pentaerythritol diacrylate ...
Johari G P - - 2010
Equimolar mixtures of acetaminophen-aspirin, acetaminophen-quinidine, and benzoic acid-progesterone have been vitrified and dielectric properties of their glassy and ultraviscous alloys have been studied. For 20 K/min heating rate, their T(g)s are 266, 330, and 263 K, respectively. The relaxation has an asymmetric distribution of times, and the distribution parameter increases ...
Tanaka Hisashi - - 2010
The photosonolysis of oxalic acid was carried out in an Ar atmosphere. The detectable products of sonolysis were CO(2), CO, H(2), and H(2)O(2). The yield of CO(2) was higher than that for the sum of sonolysis and photolysis reactions. Namely, a synergistic effect was observed during simultaneous irradiations of 200 ...
Rajeshkannan R - - 2010
In the present study, the parameters, temperature, adsorbent dose, contact time, adsorbent size and agitation speed were optimized for Acid Blue 9 removal from aqueous medium by using response surface methodology (RSM). The optimum conditions for maximum removal of Acid Blue 9 from an aqueous solution of 100 mg/l were ...
Jeyabharathi Chinnaiah - - 2010
Gradual, yet a great leap: Electrosynthesized surfactant-stabilized gold atomic clusters (AuACs; Au(n) , 5≤n≤13) electrocatalyze the oxygen reduction reaction (ORR) in acid solution at low overpotentials. Depending on the surfactant concentration, the ORR mechanism gradually transits from a direct four-electron to a two-electron pathway (see picture; SHE=standard hydrogen electrode), which ...
Wongwilai Wasin - - 2010
A modification of a webcam camera for use as a small and low cost detector was demonstrated with a simple lab-on-chip reactor. Real time continuous monitoring of the reaction zone could be done. Acid-base neutralization with phenolphthalein indicator was used as a model reaction. The fading of pink color of ...
Kosmulski Marek - - 2010
The presence of titania powder (chiefly anatase) enhanced electrolytic dissociation of oxalic acid in lower aliphatic alcohols (but not in water). The surface-induced dissociation was manifested in enhanced electric conductance of a dispersion containing solvent, oxalic acid, and titania, which was substantially higher than the conductance of dispersion containing only ...
Cardoso C - - 2010
Two ready-to-eat minced fish products from hake were developed, their proximate composition and fatty acid profiles determined and their quality changes followed during 3.5 months under refrigeration at 2 ± 1 (°)C and 10 ± 1 °C. These products contain dietary fiber and are innovative and healthy. The formulation was ...
Moazeni Mohammad - - 2010
The most confident way for treatment of hydatid cyst is surgical operation. Spillage of the cyst contents during the operation is the major cause of recurrence after hydatid cyst surgery. Instillation of scolicidal agent into hydatid cyst is the most commonly employed measure to prevent this complication. In the present ...
Zimmermann Tomás - - 2010
This work is focused on the computational studies of reactions of hydrated forms of cisplatin with sulphur-containing amino acids cysteine and methionine. First, the appropriate model for solvation of the examined complexes was searched for. The suggested procedure employs the B3LYP density functional, 6-311++G(2df,2pd) basis set with Stuttgart-Dresden pseudopotentials on ...
Xiaoli Chai - - 2010
An equilibrium dialysis combined with a (14)C-labeling method was used to study the abiotic association of phthalic acid esters (PAEs) with dissolved humic substances (HS) and its influence on the fate of PAEs in landfill leachate. Elemental analysis and FTIR spectral analysis were carried out on the humic acid (HA) ...
Miller Stuart D - - 2010
In the long-term phase of an acid rock drainage (ARD) evolution profile, after any short-term neutralisation capacity provided by carbonate minerals is exhausted, the net acid release is a product of a declining acid generation rate (AGR) and a slower, long-term acid neutralisation rate mainly provided by gangue silicate minerals. ...
Rupčić Jasminka - - 2010
The neutral lipid fraction of the aerobically grown starter yeast culture of a Saccharomyces cerevisiae brewing strain, and three-first recycled yeast generations exposed to multiple stress factors during beer fermentation was studied. No pronounced changes in the cellular neutral lipid content between the non-stressed starter and stressed recycled cells were ...
Wang Wendong - - 2010
This article focused on the influences of fulvic acid and humic acid on aluminum speciation in drinking water. Factors including the concentration of residual chlorine and pH value had been concerned. Aluminum species investigated in the experiments included inorganic mononuclear, organic mononuclear, mononuclear, polymer, soluble, and suspended forms. It was ...
Uyguner C S - - 2010
The present study investigated the removal efficiency of aqueous humic acid solutions by TiO(2) photocatalytic degradation in the presence of Cu(II) species. The pseudo-first-order kinetics revealed rate constants as 9.87 x 10(-3), 7.19 x 10(-3), 3.81 x 10(-3) min(-1) for Color(436), UV(254) and TOC, respectively. Comparatively, lower rate constants were ...
Wu Xing - - 2010
Humic acid is an important pool of heavy metals in sediments. Generally, the presence of refractory humic matter in aquatic systems would decrease the bioavailability of Cd and hence control the bioaccumulation of Cd in benthic animals. In the present work, we applied a suspending system to determine the relative ...
Ryu Miyoung - - 2010
We have investigated dissolution and surface reaction of calcite and aragonite in amino acid solutions of L-glutamic (L-glu) and L-aspartic acid (L-asp) at weak acidity of above pH 3. The surface reactions of calcite and aragonite were related with the dissolution. Calcite was dissolved in both solutions but the dissolution ...
Sundaram Shanthy - - 2010
Rosmarinic acid (RA) is an ester of caffeic acid and 3, 4-dihydroxyphenyllacticacid. It is commonly found in Coleus blumei, Salvia officinalis, Melissa officinalis and Rosmarinus officinalis. The biosynthesis of RA starts with precursor molecules L-phenylalanine and L-tyrosine. Simulation of RA biosynthetic pathway was done using Gepasi Software, includes the reaction ...
Hauser Philippe M - - 2010
Pneumocystis jirovecii is a fungus causing severe pneumonia in immuno-compromised patients. Progress in understanding its pathogenicity and epidemiology has been hampered by the lack of a long-term in vitro culture method. Obligate parasitism of this pathogen has been suggested on the basis of various features but remains controversial. We analysed ...
Gao Juan - - 2010
The interaction of sulfonamide antimicrobial agents with smectite clay minerals and humic acid (HA)-clay complexes was investigated in batch experiments to assess the influence of adsorbed humic acid on sulfonamide sorption. Soil HA-clay complexes were produced at HA:clay ratios of 1:5, 1:50, and 1:100 (w/w). Vibrational and electronic spectroscopy indicated ...
Arakaki Takemitsu - - 2010
We investigated the contribution of fulvic acid to the photoformation of Fe(II) using aqueous Suwannee River fulvic acid (SRFA) as a surrogate for the humic-like substances (HULIS) found in atmospheric condensed phases. The effects of pH (3.2, 4.1, and 5.0) and wavelength (313, 334, 366, and 405nm) on Fe(II) photoformation ...
Rani Radha - - 2010
Adsorption of phorate, an organophosphorus pesticide, on a vertisol soil was studied. The resulting data were well described by Freundlich and Langmuir adsorption isotherms. Adsorption was fast and the equilibrium was established within 8 h, which is comparatively less than reported previously. The mechanism of interaction between phorate and clay ...
Lu Longfei - - 2010
The adsorption of stearic acid on both sodium montmorillonites and calcium montmorillonites has been studied by near infrared spectroscopy complimented with infrared spectroscopy. Upon adsorption of stearic acid on Ca-Mt additional near infrared bands are observed at 8236 cm(-1) and is assigned to an interaction of stearic acid with the ...
Gayathri P - - 2010
Decolorisation of dye solutions by cobalt activated persulphate and ultrasonication has been investigated. Rhodamine B, Methylene Blue dye (basic dyes) and Acid orange II, Acid scarlet red 3R (acid dyes) were used as model compounds in this study. Immobilized cobalt ions, activated the persulphate to form highly reactive sulphate radicals. ...
Hattori Toshiaki - - 2010
Five chitosan oligosaccharides were separated in acidic aqueous solution by capillary electrophoresis (CE) with indirect photometric detection using a positively coated capillary. Electrophoretic mobility of the chitooligosaccharides (COSs) depended on the number of monomer units in acidic aqueous solution, similar to other polyelectrolyte oligomers. The separation was developed in nitric ...
Park In - - 2009
We herein describe a soft-chemical route to exfoliation of layered semiconductive titanoniobate (KTiNbO5) into individual oxide nanosheets. The protonic layered titanoniobate (HTiNbO5), derived from KTiNbO5, is reacted with zwitterionic aminoundecanoic acid (H2N(CH2)10COOH; AUA) to replace the interlayer H+ ions with AUA molecules in an acidic aqueous solution (pH approximately 3). ...
Zhou Zunlong - - 2010
Desorption of pyrene and phenanthrene, from two charcoals and humic acid preloaded charcoals were studied. Desorption occurred obviously in two fractions, with rapid and slow desorption rate constant ranging from 0.18 to 0.71 d(-1), and from 6.3 x 10(-5) to 7.4 x 10(-3) d(-1), respectively. Both the kinetics and percentage ...
Bize C?cile - - 2010
An amino-calix[6]arene was combined with sugar-based surfactants, using an acid-base reaction, to obtain an original catanionic association. Physicochemical studies showed the spontaneous formation of stable vesicles in aqueous solution.
Breslow Ronald - - 2010
We show how the amino acids needed on prebiotic earth in their homochiral L form can be produced by a reaction of L-alpha-methyl amino acids-that have been identified in the Murchison meteorite-with alpha-keto acids under credible prebiotic conditions. When they are simply heated together they perform a process of decarboxylative ...
Adamczyk Katrin - - 2009
Despite the widespread importance of aqueous bicarbonate chemistry, its conjugate acid, carbonic acid, has remained uncharacterized in solution. Here we report the generation of deuterated carbonic acid in deuterium oxide solution by ultrafast protonation of bicarbonate and its persistence for nanoseconds. We follow the reaction dynamics upon photoexcitation of a ...
Park Jin-Ho - - 2009
Hydrogen bonding-induced redispersion of the aggregated Au nanoparticles upon N-hydroxysuccinimide ester bioconjugations may provide a simple and colorimetric tool as an optical sensor to detect a trace amount of amino acids as low as approximately 10(-6) M in an aqueous solution.
Fomba Khanneh Wadinga - - 2009
A new NMR option for monitoring the mobility of organic contaminants in SOM in the solid state has been successfully applied for the first time. This recently available noninvasive technique, magic angle spinning pulsed-field gradient (MAS PFG) NMR, combines both NMR spectroscopy and diffusometry to selectively monitor the diffusion of ...
Choquenet Benjamin - - 2009
As soon as the weather turns sunny, everyone wants a tan. People with skin phototypes III and IV, called melanocompetent, have no problem meeting this fashion requirement. But things are quite different for people with phototypes I and II and so these individuals look for alternative solutions. In essence, light ...
Farré Ricard R Center for Gastroenterological Research, Catholic University Leuven, - - 2010
Oesophageal mucosa dilated intercellular spaces (DIS) may be important for symptom perception in non-erosive reflux disease (NERD). Patients with NERD might have DIS even in the proximal oesophagus. We aimed to assess the effect of oesophageal perfusions with acid and weakly acidic solutions on 'exposed' and 'non-exposed' oesophageal mucosa and ...
Hanay Ozge - - 2009
In this study, the effect of pH and washing solution on the removal of lead from sewage sludge by electrokinetics was investigated. The six experimental runs were carried out at two different pH values--3 and 4--using acetic acid, nitric acid and phosphoric acid. In addition, the sequential chemical extraction scheme ...
Ter Laak Thomas L - - 2009
In this study, the uptake of pyrene and benzo[b]fluoranthene by an aquatic worm (Lumbriculus variegatus) and a poly(dimethylsiloxane) coated glass fiber was studied at different humic acid concentrations. The accumulation of pyrene was not affected by the presence of the humic matrix. However, the accumulation rate of benzo[b]fluoranthene increased a ...
Gao Jingfeng - - 2010
Batch biosorption experiments were carried out for the removal of Acid Yellow 17 from aqueous solution using non-living aerobic granular sludge as an effective biosorbent. The effects of solution pH value, biosorbent dosage, initial Acid Yellow 17 concentration, NaCl concentration and temperature on the biosorption were investigated. The experimental results ...
Pintado Cristina M B S - - 2009
Whey protein isolate and glycerol were mixed to form a matrix to incorporate antimicrobial agents and produce edible films with antimicrobial activity against Listeria monocytogenes strains isolated from cheeses. Various organic acids were used to decrease pH down to approximately 3. In a preliminary assay without nisin, the effect of ...
Matsuoka Tsuneyoshi - - 2009
This article investigates solution additives that prevent misfolding of lysozyme from heating treatment and during refolding processes. Comparison of heat treatment of native lysozyme and oxidative refolding from the reduced and denatured state of lysozyme in the presence of 44 different additives revealed an indispensable chemical structure for the additives ...
Sakamoto Junko - - 2009
When a solution containing xylose and L-lysine is heated under weakly acidic conditions, it turns brown by the Maillard reaction. We isolated here two novel yellow compounds from a heated solution containing xylose and lysine, and identified pyrrolyl-methylidene-pyrrolone derivatives named dilysyldipyrrolones A and B. Their chemical structures were elucidated by ...
Gao Ling - - 2009
A new series of carbamothioic acid-containing periodic mesoporous organosilica (PMO) materials has been synthesized by a direct cocondensation method, in which an organosilica precursor N,S-bis[3-(triethoxysilyl)propyl]carbamothioic acid (MI) is treated with tetraethyl orthosilicate (TEOS), and the nonionic surfactant Pluronic 123 (P123) is used as a template under acidic conditions in the ...
Yu Chunyan - - 2009
To elucidate the existence of phthalocyanine-like (Pc-like) substances in humic acids (HA) and their roles in photochemical transformation of organic pollutants, Pc-imprinted polymers (MIP) were synthesized successfully and employed to separate Pc-like substances from HA. The fraction bound by MIP (F(mip-b)) presented better photochemical activity for degradation of 2,4-dichlorophenoxyacetic acid ...
Lippold Holger - - 2009
Migration of contaminants with low affinity for the aqueous phase is essentially governed by interaction with mobile carriers such as humic colloids. Their impact is, however, not sufficiently described by interaction constants alone since the humic carriers themselves are subject to a solid-liquid distribution that depends on geochemical parameters. In ...
Li Huan - - 2009
A new method was introduced to reduce waste activated sludge and extract humic acid for liquid fertilizer. Sludge was disintegrated with NaOH (0.4 g/g dry solid, 8 h) and then centrifuged to obtain the supernatant. The residual sludge was then dewatered, while the supernatant was used to extract humic acid ...
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