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Neta E R D - - 2009
Protonated organic acid species have been shown to be the primary stimuli responsible for sour taste of organic acids. However, we have observed that sour taste may be modulated when the pH of acid solutions is raised using sodium hydroxide. Objectives were to evaluate the effect of pH adjustment on ...
Hashiguchi-Ishiguro Michiru - - 2009
Our previous study has already clarified that partially decomposed alginate (Alg53) by Vibrio alginolyticus SUN53 has a competitive inhibitory effect on sucrase. The objective of this study is to evaluate the influence of Alg53 on the production of glucan from sucrose by glucosyltransferase and acid from glucose by Streptococcus sobrinus ...
Moissette A - - 2009
In situ diffuse reflectance UV-visible, Raman scattering and EPR experiments, carried out as a function of time after phenothiazine (PTZ) direct exposure to thermally activated acid H(n)ZSM-5 zeolite without any solvent, provide evidence of phenothiazine sorption and simultaneous spontaneous ionization. For comparison, phenothiazine behavior was investigated within non acidic zeolite ...
Tang Jianting - - 2009
Mesoporous titanosilicates with high titanium content were synthesized under mild acidic conditions (pH=4.4, HAc-NaAc buffer solution) by co-condensation of acetylacetone-modified titanium isopropoxide (Ti(OBu(n))(3) (acac)) and mixture of sodium silicate with tetramethoxysilane (TMOS) or tetraethoxysilane (TEOS) or tetrakis(2-hydroxyethyl)orthosilicate (EGMS), using block copolymer Pluronic P123 as template. The combined results of XRD, ...
Seiss Mario - - 2009
OBJECTIVES: Comonomers used in dental restorative materials, e.g. triethylenglycoledimethacrylate (TEGDMA), hydroxyethylmethacrylate (HEMA) and methylmethacylic acid (MMA) are methacrylic acid esters. Because of the chemical structure of these esters in earlier studies two different in vitro pathways were suggested. The present study was performed in order to analyze which of these ...
Ding Feizhi - - 2009
Electronic structure theory, mainly the density functional theory (DFT), is applied to calculate the pK(a) values for a variety of organic acids in several nonaqueous solvents: namely DMSO, MeCN, and THF. Following the supermolecule approach the solute molecule, together with a few solvent molecules in close proximity, is treated explicitly ...
Valizadeh Hadi - - 2009
The objective of this study was to forecast and optimize the glucosamine production yield from chitin (obtained from Persian Gulf shrimp) by means of genetic algorithm (GA), particle swarm optimization (PSO), and artificial neural networks (ANNs) as tools of artificial intelligence methods. Three factors (acid concentration, acid solution to chitin ...
Tsang Daniel C W - - 2009
The influence of natural organic matter on contaminant removal by Fe(0) systems has been of increasing concern. Recent studies have shown that, in addition to direct sorption on the Fe(0) surfaces, humic acid complexation with dissolved iron released from corrosion results in the formation of colloids and aggregates in solution ...
Nagahama Tatsumi - - 2009
Aplysia kurodai feeds on Ulva but rejects Gelidium and Pachydictyon with distinct patterned jaw movements. We previously demonstrated that these movements are induced by taste alone. Thus some chemicals may contribute to induction of these responses. We explored the amino acids composition of Ulva, Gelidium and Pachydictyon extracts used during ...
Yantasee Wassana - - 2009
The increased demand for the lanthanides in commercial products result in increased production of lanthanide containing ores, which increases public exposure to the lanthanides, both from various commercial products and from production wastes/effluents. This work investigates lanthanide (La, Ce, Pr, Nd, Eu, Gd and Lu) binding properties of self-assembled monolayers ...
Iglesias A - - 2009
The effect of pH and ionic strength on the interaction between pesticides (paraquat and MCPA) and humic substances (soil extracted humic acid and fulvic acid) was interpreted with a simple electrostatic model. Potentiometric titrations were carried out, the charge curves for the humic substances were obtained for three values of ...
Subbiah Deepa - - 2009
Synchronous and excitation emission matrix fluorescence (EEMF) characteristics of humic acid-surfactant interaction have been studied. The variation of synchronous and EEMF spectral maxima and intensities with humic acid (HA)-cetyltrimethylammonium bromide (CTAB) composition sensitively reflects the extent of flocculation of HA. It was found that the concentration range for co-precipitation of ...
ter Laak Thomas L - - 2009
The exchange rate of hydrophobic organic chemicals between the aqueous phase and a sorbent (e.g., soil, organism, passive sampler) is relevant for distribution processes between environmental compartments, including organisms. Dissolved phases such as humic acids, proteins, and surfactants can affect the transfer of such chemicals between the aqueous and sorbent ...
Jung J-T - - 2009
The objective of this study was to investigate the treatment efficiency of UV/TiO2 and UV/TiO2/chemical oxidant processes for the removal of humic acid and hazardous heavy metals in aqueous TiO2 suspensions. The reaction rate (k) of humic acid and hazardous heavy metals by UV/TiO2 was higher than that of UV ...
Castro Jacira T - - 2009
The efficiency of diluted nitric acid solutions for digesting regular coffee samples was evaluated employing two closed vessel procedures: one was based on microwave-assisted heating and the other was based on conductive heating using pressurized Parr bomb. The efficiency of digestion was evaluated by determining residual carbon content (RCC) and ...
Liu Tongzhou - - 2009
The influences of various geochemical constituents, such as humic acid, HCO(3)(-), and Ca(2+), on Cr(VI) removal by zero-valent iron (Fe(0)) were investigated in a batch setting. The collective impacts of humic acid, HCO(3)(-), and Ca(2+) on the Cr(VI) reduction process by Fe(0) appeared to significantly differ from their individual impacts. ...
Yang Young-Keun - - 2009
A new rhodamine-hydroxamic acid-based fluorescent chemosensor for the rapid detection of HOCl in aqueous media was developed. The system, which utilizes an irreversible HOCl-promoted oxidation reaction, responds instantaneously at room temperature with linear proportionality to the amount of HOCl. This system is highly selective for HOCl over other reactive oxygen ...
Fillion Eric - - 2009
Persistent intramolecular interactions between acidic C-H hydrogens and a variety of acceptors (X) (X = O, S, Br, Cl, and F) in solution were probed by (1)H NMR experiments, using 5-benzyl Meldrum's acid derivatives. To bring about formation of intramolecular C-H...X bonding, ortho-substituted benzyl Meldrum's acids were designed, for which ...
Park Seong-Jik - - 2009
Column experiments were performed to examine the influence of humic acid on the attachment of Escherichia coli to iron-coated sand. Results show that, in the coated sand, the average mass recovery was 2.9% in deionized water and increased sharply to 94.6% at a humic acid concentration of 16 mg/L. In ...
van Wijk Dolf - - 2009
We investigated the role of sorption in reducing bioavailability and consequently the measured toxicity of monoalkyl trimethyl ammonium salts (MAQ) under environmental conditions. The observed toxicity of MAQ in the presence of various types of sorbents was tested on algae. Decreased toxicity was found in the presence of all particulate ...
Favier G I - - 2009
AIMS: To determine the effectiveness of sucrose monolaurate (SML) and sucrose monocaprate (SMC), alone and in combination with ethylenediaminetetraacetic acid (EDTA), propionic acid (PA) or citric acid (CA) in reducing mesophilic aerobic bacteria (MAB) and Yersinia enterocolitica O:9 populations on eggshells and their damage potential on the microstructure of shell ...
Bacharaki Dimitra - - 2009
BACKGROUND/AIMS: Peritoneal dialysis solutions (PDS), new and conventional, do not yet have a clinical biocompatibility profile. We aimed at a comparative laboratory profile based on the effect of PDS on peripheral blood mononuclear cell (PBMC) cytokine release. METHOD: PBMCs from 19 healthy volunteers were incubated at a concentration of 10(6)/ml ...
Cankayali Ilkin - - 2009
BACKGROUND: There is a strong correlation between amino acid infusion and increase in energy expenditure and thermogenesis. In this study, the effects of amino acid solutions on thermogenesis and energy expenditure were investigated in intensive care patients who were diagnosed as brain death. METHODS: Twenty-six brain-dead patients were included in ...
Iwaura Rika - - 2009
The thymidylic acid appended anthracene dye 2,6-bis[5-(3'-thymidylic acid)pentyloxy]anthracene (1) was synthesized, and the self-assembly of 1 and the binary self-assembly of 1 with a complementary single-stranded 20-meric oligodeoxyadenylic acid (dA(20)) were performed in 0.1 x TE buffer solution (i.e., 1.0 x 10(-3) M Tris-HCl, 1.0 x 10(-4) M ethylenediaminetriacetic acid ...
Izutsu Ken-ichi - - 2009
The purpose of this study was to produce and characterize glass-state amorphous solids containing amino acids and organic acids that protect co-lyophilized proteins. Thermal analysis of frozen solutions containing a basic amino acid (e.g., L-arginine, L-lysine, L-histidine) and a hydroxy di- or tricarboxylic acid (e.g., citric acid, L-tartaric acid, DL-malic ...
Azlan Kamari - - 2009
The capabilities of chitosan and chitosan-EGDE (ethylene glycol diglycidyl ether) beads for removing Acid Red 37 (AR 37) and Acid Blue 25 (AB 25) from aqueous solution were examined. Chitosan beads were cross-linked with EGDE to enhance its chemical resistance and mechanical strength. Experiments were performed as a function of ...
Zhang Hua - - 2009
Dissolved organic matter (DOM) has been identified as precursor for disinfection by-products (DBPs) formation during chlorination. Recently, it has been demonstrated that the characteristics of DOM influence the DBPs formation mechanism. A study was, therefore, initiated to investigate the effects of DOM fractions on DBPs formation mechanism. In the chlorination ...
Gotloib Lazaro - - 2009
Use of one bag of glucose peritoneal dialysis fluid (PDF) results in the development of a dose-related senescent mesothelial cell phenotype not linked to acidic pH or the presence of lactate buffer. This complication derives mostly from oxidative stress induced both by glucose itself and by glucose degradation products (GDPs). ...
Safoury Omar Soliman - - 2009
Melasma is a symmetric progressive hyperpigmentation of the facial skin that occurs in all races but has a predilection for darker skin phenotypes. Depigmenting agents, laser and chemical peeling as classic Jessner's solution, modified Jessner's solution and trichloroacetic acid have been used alone and in combination in the treatment of ...
Cifuentes, L.
Two lab-scale electrohydrolysis (EH) cells have been used to study the effectiveness of this method in the recovery of sulphuric acid from copper-containing electrolytes such as those present in copper electrorefining. Results for the effect of cell current density and temperature on the processing of synthetic electrolytes have been obtained. ...
Brigante Marcello - - 2008
By means of a wetted-wall flow tube, we studied the multiphase chemistry of ozone on aqueous solutions containing fulvic acids (FA), taken as proxies for atmospheric "humic like substances", so-called HULIS. In these experiments, the loss of gaseous O3 was monitored by UV-visible absorption spectroscopy at the reactor outlet (i.e., ...
Hatori Nahoko - - 2008
Solid-phase extraction (SPE) of gallium(III) with hydrophobic 8-quinolinol derivatives (HQs)-impregnated resin from aqueous acidic and alkaline solutions has been investigated. The HQs used were 7-(4-ethyl-1-methyloctyl)-8-quinolinol (HEMOQ), 5-octyloxymethyl-8-quinolinol (HO(8)Q), 2-methyl-5-octyloxymethyl-8-quinolinol (HMO(8)Q), 5-dioctylaminomethyl-8-quinolinol (HN(8)Q), 7-bromo-5-octyloxymethyl-8-quinolinol (HBrO(8)Q), and 5-(2-ethylhexyloxymethyl)-8-quinolinol (HOEHQ). Various factors affecting the SPE, such as the substituents of the HQs, HCl ...
Claret Francis - - 2008
Sorptive fractionation of Suwannee River Fulvic Acid (SRFA) and Purified Aldrich Humic Acid (PAHA) on alpha-Al2O3 at pH 6 was probed in the supernatant using different spectroscopic techniques. Comparison of dissolved organic carbon (DOC) analysis with UV/vis spectrophotometric measurements at 254 nm, including specific UV absorbance (SUVA) calculation, revealed a ...
Russell Mark A - - 2009
The kinetics and mechanism of the deprotection (detritylation) of 5'-O-(4,4'-dimethoxytrityl)-2'-deoxythymidine nucleoside catalysed by dichloroacetic acid to give a 4,4'-dimethoxytrityl carbocation have been studied in toluene, dichloromethane and acetonitrile. There is little or no effect of solvent polarity on the equilibrium and rate constants. Entropies of activation are highly negative approximately ...
Xu Jing - - 2009
Diffusion dialysis using a series of anion exchange membranes was employed to recover HCl acid from the waste acid solution. Effects of flow rate, flow rate ratio of water to feed, and Fe ion concentration on the recovery of HCl were investigated. It was found that the flow rate ratio ...
Sonawane S H - - 2009
Synthesis of nanoclay nanocomposite has been undertaken by using polyacryalic acid (PAA) in aqueous medium and ultrasound environment and its application in dye removal has been investigated. The synthesized product was characterized by using FTIR and XRD techniques. The sonosorption capacity of the product namely PAA-nanoclay composite was determined by ...
Beyer Keith D - - 2008
We have studied liquid/solid phase diagrams and water activities of the dicarboxylic acid/water binary systems for maleic, dl-malic, glutaric, and succinc acids using differential scanning calorimetry, infrared (IR) spectroscopy of thin films, and conductivity analysis of saturated solutions. For each binary system we report the measurements of the ice melting ...
Demadis Konstantinos D - - 2008
This article reports the inhibitory effects of phosphonated chitosan (PCH, synthesized from chitosan (CHS) by a Mannich-type reaction) on the in vitro silicic acid condensation. In particular, the ability of PCH to retard silicic acid condensation in aqueous supersaturated solutions at circumneutral pH is studied. Furthermore, the effect of anionic ...
Zhang Long - - 2009
Dissolved organic matter (DOM) from wastewater rejected by nanofiltration from a landfill leachate treatment plant was fractionated into humic acid (HA), fulvic acid (FA) and hydrophilic (HyI) fractions. It was found that humic substances (HA and FA) composed 75% of the total dissolved organic carbon (DOC) concentration of the DOM, ...
Kim Franklin - - 2008
High aspect ratio gold nanowires with single crystalline surface have long been a missing piece in the toolbox of plasmonics metal nanostructures. Such wires are now made with a room temperature, surfactant assisted chemical synthesis in acidic aqueous solution. The diameters and lengths of the multiply twinned gold nanowires can ...
Janos Pavel - - 2009
Spruce wood shavings from Picea abies were used for an adsorptive removal of both basic as well as acid dyes from waters. The sorption properties of the sorbents were modified with HCl, Na(2)CO(3) and Na(2)HPO(4). The treatment of the wood sorbents with alkaline carbonate solution as well as with phosphate ...
Tanabe Kazuhito - - 2008
We employed X-irradiation to activate a caged amino acid with a 2-oxoalkyl group. We designed and synthesized tyrosine derivative caged by a 2-oxoalkyl group (Tyr(Oxo)) to evaluate its radiolytic one-electron reduction characteristics in aqueous solution. Upon hypoxic X-irradiation, Tyr(Oxo) released a 2-oxopropyl group to form the corresponding uncaged tyrosine. In ...
Van Loon Lisa L - - 2008
The diffusion of methanol into 0-96.5 wt % sulfuric acid solutions was followed using Raman spectroscopy. Because methanol reacts to form protonated methanol (CH 3OH 2 (+)) and methyl hydrogen sulfate in H 2SO 4 solutions, the reported diffusion coefficients, D, are effective diffusion coefficients that include all of the ...
Hirayama Teruhisa - - 2008
PURPOSE: The purpose of this study was to investigate the ion release from titanium casts in solutions of mixed organic acids and to reconsider the possibility of allergic reactions to titanium. METHODS: Cast specimens were made from commercially pure titanium. For the immersion solutions, we prepared two types of organic ...
Ryu Won Hee - - 2008
We synthesized TiO2 nanotube array by anodizing in a solution of malonic acid (HOOCCH2COOH) and NH4F, and analyzed the morphology of the nanotube using scanning electron microscopy (SEM). The morphology of TiO2 nanotube was largely affected by anodizing time, anodizing voltage, and malonic acid concentration. With increasing the anodizing voltage ...
Park Jin-Young - - 2008
We report a novel concept of sensing glycated hemoglobin, HbA 1c, which is now the most important index for a long-term average blood glucose level, by first selectively immobilizing it on the thiophene-3-boronic acid (T3BA) self-assembled monolayer (SAM)-covered gold electrode by a selective chemical reaction with boronic acid. HbA 1c ...
Cheung W H - - 2009
In the present study, nanochitosan emulsion has been produced in a suspension form by adding tripolyphosphate solution into a chitosan solution drop-wise. The adsorption capacities of four acid dyes, namely, Acid Orange 10 (AO10), Acid Orange 12 (AO12), Acid Red 18 (AR18) and Acid Red 73 (AR73) on nanochitosan, have ...
Kim Hyun Jik - - 2008
OBJECTIVES/HYPOTHESIS: Saline irrigation would be more effective for chronic sinusitis patients if it had bactericidal effects. Low concentrations of hypochlorous acid may be used as a nasal irrigation solution. First, we developed a 0.85% NaCl solution by adding NaCl to tap water (pH 7.0 and 8.4) and measuring the concentration ...
Zhang Hua - - 2009
Dissolved organic matter (DOM) in effluent from a conventional sewage treatment plant was isolated using resin adsorbents into six classes: hydrophobic bases (HoB), hydrophobic acids (HoA) and hydrophobic neutrals (HoN); hydrophilic bases (HiB), hydrophilic acids (HiA) and hydrophilic neutrals (HiN). Organic acids were the most abundant fractions of DOM. Hydrophobic ...
Carvalho Sandra I M - - 2008
Large volumes of wastewater with a high organic load are generated by the pulp and paper industry that negatively affect the quality of receiving waters. The main waste products in the pulp mill effluents are lignin derived macromolecular compounds, which are similar to natural humic substances and very resistant to ...
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