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Pericin Draginja M - - 2009
Aspergillopepsin I, an acid protease, was purified using an aqueous two-phase system that comprised various combinations of polyethylene glycol (PEG), NaH2PO4 and NaCl. Partition of the enzyme depended upon the molecular mass of the PEG and the presence of NaCl. With PEG 1500, 4000 and 6000, the partition coefficients were ...
Pramanik Sukhendu K - - 2008
Penoxsulam is a triazolopyrimidine sulfonamide group of rice herbicide. The phototransformation of penoxsulam was studied under UV light (lambda max >or= 290 nm) and sunlight in aqueous methanol and acetonitrile solvent system using TiO2 as sensitizer. The rate of photodegradation of penoxsulam in different solvent systems followed first-order kinetics and ...
Schiller Alexander - - 2008
The solution-phase sensor array of three cationic bis-boronic acid appended benzyl viologens (BBV) and the anionic fluorescent dye, 8-hydroxypyrene-1,3,6-trisulfonic acid trisodium salt (HPTS), is able to discriminate among five phospho sugars, four nucleotides and three neutral saccharides in aqueous buffered solution at low mM concentrations. Linear discriminant analysis, principal component ...
Lin Daohui - - 2008
Dissolved organic matter (DOM) has been reported to stabilize carbon nanotube (CNT) suspensions, which increases concern over the subsequent transport and behavior of CNTs. However, it is unknown exactly which compounds or functional groups cause the stabilization of CNTs in natural environments. Naturally occurring tannic acid (TA), which has a ...
Kolokassidou K - - 2009
Disposed olive cake generates hydrophilic components that can be mobilized in the aquatic environment. This paper deals with the characterization of such components, isolated by alkaline extraction. It is shown that these substances possess properties very much resembling humic acid, including a substantial inventory of proton exchanging groups. Extraction and ...
Araújo Geórgia C L - - 2009
In this work the influence of four different ligands present in the xylem sap of Quercus ilex (histidine, citric, oxalic and aspartic acids) on Ni(II) adsorption by xylem was investigated. Grinded xylem was trapped in acrylic columns and solutions of Ni(II), in the absence and presence of the four ligands ...
Billinsky Jennifer L - - 2008
The lignan meso-nordihydroguaiaretic acid is known to undergo spontaneous oxidation in alkaline solution. In the presence of the trapping agent glutathione, the major oxidation products are consistent with the formation of a meso-nordihydroguaiaretic acid ortho-quinone. In the absence of a trapping agent however, the major oxidation product of meso-nordihydroguaiaretic acid ...
Sato Keiichi - - 2008
Volatile acidic solutes were used to make dilute solutions, which were frozen by various methods. The concentration of solutes and the pH of the samples were measured before and after being frozen. When the sample solution is frozen from the bottom to the top, solutes are concentrated into the unfrozen ...
Bratskaya S - - 2008
Charge characteristics of humic and fulvic acids of a different origin (inshore soils, peat, marine sediments, and soil (lysimetric) waters) were evaluated by means of two alternative methods - colloid titration and potentiometric titration. In order to elucidate possible limitations of the colloid titration as an express method of analysis ...
Fukushima Masami - - 2009
An analytical scheme for the separation of humic substances (HSs) and non-humic substances (non-HSs) was established to estimate the humification index (HI), which was defined as the ratio of HS carbon content to non-HS carbon content. The alkaline compost-extract contained a mixture of HSs and non-HSs, while acidification of the ...
Mecozzi Mauro - - 2009
In this paper the marine organic matter soluble in an alkaline medium called extractable humic substance (EHS), was extracted from three sediment samples of Tyrrhenian Sea and separated by precipitation at pH 2 in the two fractions of fulvic acids (FAs) and humic acids (HAs). FAs were further fractionated in ...
Empadinhas Nuno - - 2008
Mannosylglycerate (MG) is an intracellular organic solute found in some red algae, and several thermophilic bacteria and hyperthermophilic archaea. Glucosylglycerate (GG) was identified at the reducing end of a polysaccharide from mycobacteria and in a free form in a very few mesophilic bacteria and halophilic archaea. MG has a genuine ...
Gannu Ramesh - - 2008
This investigation studied the effect of vehicles on the in vitro permeation of carvedilol from saturated solutions across porcine skin and selected appropriate penetration enhancers. Labrasol, Transcutol, polyethylene glycol 400, propylene glycol, ethanol, oleic acid, isopropyl myristate, and phosphate buffered saline (pH 7.4) containing 40% v/v polyethylene glycol 400 as ...
Ayotte Patrick - - 2008
A molecular-level description of the structural and dynamical aspects that are responsible for the weak acid behaviour of dilute hydrofluoric acid solutions and their unusual increased acidity at near equimolar concentrations continues to elude us. We address this problem by reporting reflection-absorption infrared spectra (RAIRS) of cryogenic HF-H(2)O binary mixtures ...
Ross M W - - 2008
Solid-state Fourier transform infrared spectroscopy (FTIR), evolved gas analysis-FTIR (EGA-FTIR), thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC) have been used to investigate the desorption of nitric acid from boehmite and from gibbsite. Samples containing between 3 and 36% of adsorbed nitric acid by mass were prepared by placing ...
Pitois Aurélien - - 2008
A kinetic study of Aldrich humic acid sorption onto a quartz sand surface has revealed an initial rapid uptake of humic acid molecules followed by a much slower sorption. The humic acid molecular weight and chemical fractionation resulting from adsorption onto the simple quartz sand surface were investigated for the ...
Baigorri Roberto - - 2008
The aim of this work is to explore the suitability of the complementary use of mass spectra and the corresponding statistical analysis (principal components-Pareto analysis (PCA) and discriminant analysis (DA)) of these spectra to differentiate diverse humic samples as a function of their structural and conformational features. To this end, ...
Shin Chang-Hoon - - 2009
Recovery of acetic acid (HAc) from the waste etching solution discharged from silicon wafer manufacturing process has been attempted by using solvent extraction process. For this purpose 2-ethylhexyl alcohol (EHA) was used as organic solvent. In the pre-treatment stage >99% silicon and hydrofluoric acid was removed from the solution by ...
Marwani Hadi M - - 2009
In this study, the association behavior of pyrene with different dissolved humic materials (DHM) was investigated utilizing the recently developed segmented frequency-domain fluorescence lifetime method. The humic materials involved in this study consisted of three commercially available International Humic Substances Society standards (Suwannee River fulvic acid reference, SRFAR, Leonardite humic ...
Cafaggi S - - 2008
A solubility phase study was carried out to investigate the ability of Poloxamer 407 (P407) to solubilise tolfenamic acid. P407 considerably enhanced the solubility of this anti-inflammatory agent, by increasing its concentration in aqueous solution at least 2000-fold (up to C=4mM), when present at 12% (w/w) at 25 degrees C. ...
Wang Xuming - - 2008
In the study described here, the surface structure of a self-assembly octyl hydroxamic acid at a calcium fluoride (CaF(2)) surface is evaluated using sum-frequency vibrational spectroscopy (SFVS). Of particular significance are the results that show octyl hydroxamic acid adsorbs at the fluorite surface from octanol solution and has more ordering ...
Zhang Dong - - 2008
A variety of reactions of singlet oxygen with metal-bound thiolates are described, and contrasted with the photooxidation of organic sulfides. Superficially, these two processes appear to involve similar mechanisms, but there are important differences: unlike the photooxidation of organic sulfides, the rate of the initial reaction of metal-thiolates with singlet ...
Kim Hoikyung - - 2008
We studied the production and stability of chlorine dioxide (ClO(2)) in organic acid solutions and its effectiveness in killing Bacillus cereus spores. Sodium chlorite (5000, 10,000, or 50,000 microg/ml) was added to 5% acetic, citric, or lactic acid solution, adjusted to pH 3.0, 4.0, 5.0, or 6.0, and held at ...
Xu Jufang - - 2008
Photodegradation of seratrodast ([+/-]-7-(3,5,6-trimethyl-1,4-benzoquinone-2-yl)-7-phenyl-heptanoic acid, SD), a p-benzoquinone anti-asthmatic drug, has been investigated in different solutions. HPLC analysis showed that SD was degradated under UV irradiation at 254 nm to afford three major products (SD1, SD2 and SD3) in methanol and in acetonitrile/H2O solutions, while only two of them (SD2 ...
Wang Xilong - - 2008
Sorption of three types of dissolved organic matter (DOM; i.e., humic acid, peptone and alpha-phenylalanine) by a mutiwalled carbon nanotube (MWNT40) and sorption of phenanthrene (Phen), naphthalene (Naph), and 1-naphthol (1-Naph) by the original and DOM-coated MWNT40 were examined. Sorption data of Phen, Naph, and 1-Naph by all sorbents were ...
Chilom Gabriela - - 2008
Leonardite and Elliot soil humic acids have been analyzed by laser desorption ionization mass spectrometry (LDI MS) in the m/z 4000-200,000 range. Positive ion mass spectra for each humic acid obtained under optimum conditions showed a broad high-mass distribution between m/z 20,000 and 80,000. The dependence of the mass distribution ...
Watanabe Akira - - 2008
To find a certain relation between the composition of carbon functional groups of humic acids derived from liquid state (13)C nuclear magnetic resonance (NMR) spectra acquired with inverse-gated decoupling (IGD), known as a quantitative pulse sequence, and that by solid-state (13)C NMR with cross polarization/magic angle spinning (CPMAS) techniques, fifteen ...
Kim H S - - 2008
This paper describes a study on the role of limestone on the dissolution of phosphates when phosphate-containing sediments are put under anaerobic conditions. Anaerobic decomposition of organic substances produces both organic acids and carbonic acids which in turn could accelerate the dissolution of the phosphates. If limestone coexisted, both phosphate ...
Alcántara-Garduño Martha E - - 2008
The combined flushing and oxidation process using acetic acid and ozone has been used successfully to remove trichloroethylene (TCE) completely from contaminated soil. In this study, the effects of humic acid, a fraction of the organic matter in soil, over the performance of TCE decomposition was evaluated. TCE decomposition by ...
Amir Soumia - - 2008
In Marrakech, solid by-products from tanneries are highly polluting, generating large amounts of nitrogenous and organic matter. In the present study composting is tested as a cost-effective method for waste management to overcome many of the environmental hazards and produce a stable, rich material for soil fertilization. Two composting trials ...
Wang Shujing - - 2008
The objective of the present investigation was to clarify the mechanism by which Labrafac Lipophile WL 1349 (WL 1349) enhanced the oral bioavailability (BA) of hydroxysafflor yellow A (HSYA), the representative low permeable hydrophilic (biopharmaceutic classification system (BCS) Class III) drug. HSYA-phospholipid complex was prepared, and dissolved into WL 1349 ...
Brigante Maximiliano - - 2008
The dissolution kinetics of humic acid particles has been studied in batch experiments, and the effects of monocarboxylic (formic, acetic, and propionic) acids are reported. The dissolution rate of the particles is significantly affected by the presence of monocarboxylic acids in the pH range 4-10. At pH 7, for example, ...
Vinod V T P - - 2008
Gum kondagogu ( Cochlospermum gossypium) is a tree exudate gum that belongs to the family Bixaceae. Compositional analysis of the gum by HPLC and LC-MS revealed uronic acids to be the major component of the polymer ( approximately 26 mol %). Furthermore, analysis of the gum by GC-MS indicated the ...
Sukul Premasis - - 2008
Photolysis of 14C-sulfadiazine in aqueous solution under simulated sunlight followed first-order kinetics. The impact of H2O2, humic acid, fulvic acid and acetone to enhance the photodegradation of sulfadiazine (SDZ) was studied. Six photoproducts, 4-OH-SDZ, 5-OH-SDZ, N-formyl-SDZ, 4-[2-iminopyrimidine-1(2H)-yl] aniline, 2-aminopyrimidine, and aniline were identified. Extrusion of SO2 was found to be ...
Wan Ngah W S - - 2008
The adsorption of humic acid on crosslinked chitosan-epichlorohydrin (chitosan-ECH) beads was investigated. Chitosan-ECH beads were characterized by Fourier transform infrared spectroscopy (FTIR), surface area and pore size analyses, and scanning electron microscopy (SEM). Batch adsorption experiments were carried out and optimum humic acid adsorption on chitosan-ECH beads occurred at pH ...
Bisio C - - 2008
Acid clays were prepared by exchanging a synthetic saponite in HCl solutions of different concentration (0.01 and 1M, respectively). A combined experimental approach (XRD, HRTEM, N2 physisorption, solid-state MAS NMR, and TGA) was used to investigate on the structural, morphological, and textural features of the samples treated under mild and ...
Surugaya Naoki - - 2008
A stable solid spike for the measurement of uranium and plutonium content in nitric acid solutions of spent nuclear fuel by isotope dilution mass spectrometry has been prepared at the European Commission Institute for Reference Materials and Measurements in Belgium. The spike contains about 50 mg of uranium with a ...
Gao Qiang - - 2008
In order to disclose the dominant interfacial interaction between amino acids and ordered mesoporous materials, the adsorption behaviors of five amino acids on four mesoporous materials were investigated in aqueous solutions with adjustable amino acid concentration, ion strength, and pH. The selected amino acids were acidic amino acid glutamic acid ...
Vahl Katja - - 2008
Potentiometric FIA titrations were performed to determine enzyme activities of lipase type B from Candida antarctica, CAL-B. Two substrates, triacetin and tributyrin were hydrolyzed in phosphate buffer solutions, and the concentration change of the base component of the buffer was titrated in a carrier solution containing hydrochloric acid and potassium ...
Pineau L - - 2008
Following a French circular published in 2001, the use of glutaraldehyde for the disinfection of reusable medical devices was abandoned in favour of non-fixative disinfectants such as peracetic-acid-based solutions. Data published regarding the fixative properties of alternative disinfectants remain contradictory. We compared the effect of repetitive treatments of polytetrafluoroethylene (PTFE) ...
Vanifatova Natalia G - - 2008
Capillary zone electrophoresis (CZE) has been applied for fractionation and characterization of soil-derived humic acids (HAs). Humic acids from soddy-podzolic (HA(s)) and chernozem (HA(ch)) soils were studied as well as hydrophobic high-molecular-weight (HMW) and hydrophilic low-molecular-weight (LMW) HA(s) fractions obtained by salting-out with ammonium sulfate at a saturation of 0-40% ...
Xie Li - - 2008
Humic substances are ubiquitous redox-active organic compounds of environment. In this study, experiments were conducted to determine the reduction capacity of humic acid in the matrix of bromate and Fe(III) solutions and the role of Fe(III) in this redox process. The results showed that the humic acid regenerated Fe(II) and ...
Mount David W - - 2008
INTRODUCTIONComparing different amino acid scoring matrix-gap penalty combinations poses several problems. For example, the analysis often overlooks the purposes of different matrices; e.g., protein family or domain searching, evolutionary analysis, or structural alignment. In the past, gap penalties were usually not published or well known, thus throwing a level of ...
Park Seong Jin - - 2008
The acid-assisted and guest-induced formation of superstructures was achieved by the addition of haloacetic acids to a toluene solution of the resorcin[4]arene derivatives 1 and [60]fullerenes. The formation of dimeric superstructures that encapsulated a nanosized guest molecule was observed when appropriate acids, such as haloacetic acids, and suitable guest molecules, ...
Canudas Nieves - - 2008
The photobiological properties of 4-acetylaminophenylacetic acid (Actarit, ACT, MS-932, CAS 18699-02-0) were studied using in vitro phototoxicity assays: photohemolysis, photoperoxidation of linoleic acid and Candida sp phototoxicity test. ACT reduced nitro blue tetrazolium (NBT) when irradiated with lambda > or = 300 nm in deoxygenated aqueous buffer solution (pH 7.4). ...
Abe Keita - - 2008
A Notable decrease of the peak intensity of the capillary electrophoregram due to the dimeric SOD molecule was observed when a solution containing copper(II) chloride and ascorbic acid was added to the SOD solution, indicating that the capillary electrophoresis method is useful to detect the dissociation of the dimeric SOD ...
Joo Hyang Hee - - 2008
In vitro permeation of hinokitiol (HKL) through hairless mouse skin was investigated using a diffusion cell. Either propylene glycol (PG) or ethanol (EtOH) was used as a vehicle for HKL. After applying the HKL solutions of 0.5%. 1%, 2%, and 5% onto the skin, the amount of HKL transferred through ...
Lee Sang Hyun - - 2008
The low solubility of sugars has hampered the lipase-catalyzed synthesis of fatty acid sugar esters in organic solvents and ionic liquids (ILs), because several solvents that are able to effectively dissolve sugars are detrimental to enzymes. In this work, in order to prepare a high concentration of sugars in ILs, ...
Zhong Huan - - 2008
Artificially prepared sediments were used to investigate their binding with methylmercury (MeHg). The bioavailability of sediment-bound MeHg then was quantified by measuring the extraction by gut juice of the sipunculan Sipunculus nudus, as well as by different free amino acids and bovine serum albumin (BSA). Methylmercury distribution in different molecular ...
Chatterjee Koustuv - - 2008
The goal was to evaluate the effects of acidity, expressed as the Hammett acidity function, on chemical reactivity in freeze-dried materials (lyophiles). Dextran-sucrose-citrate and polyvinyl pyrrolidone (PVP)-sucrose-citrate aqueous solutions, adjusted to pH values of 2.6, 2.8, and 3.0 were freeze dried, and characterized by X-ray powder diffractometry, DSC, isothermal microcalorimetry, ...
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