Results 251 to 260 of about 418,530 (303)

Anoxic dissolution of troilite in acidic media

Journal of Colloid and Interface Science, 2006
The anoxic dissolution of troilite (FeS) in acidic medium has been investigated at 50 degrees C using batch dissolution experiments. Two different progress variables were followed during solid dissolution, i.e., the amounts of dissolved iron (nFe) and formed hydrogen sulfide (n(H(2)S)). The experimental studies performed at hydrogen ion concentrations (
Chirita, P., Descostes, M.
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Investigations on Squaric Acid in Superacidic Media

Chemistry – A European Journal, 2018
AbstractThe syntheses of [OC(COX)3][MF6] and [(COX)4][MF6]2⋅2 HF were carried out in superacidic media XF/MF5 (M=As, Sb; X=H, D). The degree of protonation is highly dependent on the stoichiometric ratio of the Lewis acid with regard to squaric acid.
Manuel Schickinger, Denise Cibu, Florian Zischka, Karin Stierstorfer, Christoph Jessen, Andreas Kornath   +5 more
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Photodegradation of Cinnamic Acid in Different Media

Journal of Dispersion Science and Technology, 2008
The photodegradation of cinnamic acid under UVB irradiation was evaluated in different vehicles, such as water solutions at different pH values, Tween‐20 micelles, liposomes, and O/W emulsions prepared with Xalifin 15 or Montanov 68 as emulsifiers. The increase of pH decreases the photodegradation of cinnamic acid in all the vehicles studied.
UGAZIO, Elena, CARLOTTI, Maria Eugenia, SAPINO, Simona, TROTTA, Michele, VIONE, Davide Vittorio, MINERO, Claudio   +5 more
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Baylis—Hillman Reactions in Aqueous Acidic Media.

ChemInform, 2005
AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Prakashanand Caumul, Helen C. Hailes
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Improved Activity in Acidic Media of Immobilized Lysozyme

Applied Biochemistry and Biotechnology, 1999
Polyethylene glycols (PEGs) of various chain length were used to crosslink lysozyme onto an insoluble support such as oxirane. A very high degree of modification and no inactivation of lysozyme were obtained with PEG 20000, but enzymatic activity increased up to 20 times at pH 3.0, at which point the activity of the native enzyme was lower when using ...
ZACCHIGNA, MARINA, DI LUCA GABRIELLA, LASSIANI, LUCIA, VARNAVAS ANTONIOS, PITOTTI ANNA, BOCCÙ ENRICO   +5 more
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Hydroxamic Acids as Weak Base Indicators:  Protonation in Strong Acid Media

The Journal of Organic Chemistry, 2001
The protonation equilibria of N-phenylbenzohydroxamic, benzohydroxamic, salicylhydroxamic, and N-p-tolylcinnamohydroxamic acids have been studied at 25 degrees C in concentrated sulfuric, hydrochloric, and perchloric acid media; the UV-vis spectral measurements were analyzed using the Hammett equation and the Bunnett-Olsen and excess acidity methods ...
B. GARCIA, S. IBEAS, F. J. HOYUELOS, J. M. LEAL, SECCO, FERNANDO, VENTURINI, MARCELLA   +5 more
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Applicability of excess acidity functions in low‐acidity media

Journal of Physical Organic Chemistry, 1991
AbstractIt is demonstrated that excess acidity functions do not correspond well to the pH scale in dilute solutions. Acidity constants, pK, of seven moderately weak bases were determined; they were calculated by means of excess acidity functions, since the corresponding ionizations occur at acidity levels where the pH scale is partly used.
Begoña García, José M. Leal
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Acidities of strong neutral Brønsted acids in different media

Journal of Physical Organic Chemistry, 2012
Acidities of different families of acids are examined in media of different physical and chemical nature: water, acetonitrile (AN), 1,2‐dichloroethane (DCE) and the gas phase, with special emphasis on strong acids. Included are OH (carboxylic acids, alcohols, and phenols), NH (sulfonamides, imides), and CH (phenylmalononitriles, etc.) acids as well as ...
Elin Raamat, Karl Kaupmees, Gea Ovsjannikov, Aleksander Trummal, Agnes Kütt, Jaan Saame, Ivar Koppel, Ivari Kaljurand, Lauri Lipping, Toomas Rodima, Viljar Pihl, Ilmar A. Koppel, Ivo Leito   +12 more
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Water-Phosphoric Acid Media: Electrochemical Properties

Analytical Letters, 1980
Abstract Electroactivity ranges at polished Platinum, vitreous Carbon, and Mercury electrodes are determined in H2O - H3PO4 mixtures (0.1 -14 M H3PO4). The Ferrocene system is considered as a comparison system. Ag+/Ags and AgCl/Ags systems are considered as reference systems. The Ro(H) acidity function is determined.
C. Louis, J. Bessiere
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Media Composition: Amino Acids and Cellular Homeostasis

2012
Amino acids are beneficial for the developing preimplantation embryo and therefore form an important component of culture media. This chapter will critically review the importance of amino acids for preimplantation embryos and the impact of this research for the development of sequential culture media used in many assisted conception units.
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