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71.
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74.
Jean Saint Raymond 《Set-Valued and Variational Analysis》1994,2(3):481-485
LetX be a Polish space equipped with a σ-finite regular Borel measure μ. IfE is a metric space andF a set-valued function:X → 2 E with complete values, and ifF is lower semicontinuous at almost all points ofX, we prove that there exists a Riemann-measurable selections ofF. 相似文献
75.
Gisela Saint Martin F. López O. A. Bernaola 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(2):635-638
A device consisting of poly allyl diglycol carbonate (PADC) foils with a polyethylene and polyvinyl chloride (PVC) radiator
was calibrated in order to perform the dosimetry of an 241Am-Be source covering a dose range from 0 to 3.1 mSv. Working conditions were established for a good visualization and counting
of tracks: chemical attack was made in two steps with different solutions and etching times. A good fit was obtained for the
dose as a function of the number of tracks per unit surface area. The calculated decision threshold was 0.12 mSv. 相似文献
76.
Clment De Saint Jores Clment Brandel Marie Vaccaro Najla Gharbi Isabelle Schmitz-Afonso Pascal Cardinael Rui Tamura Grard Coquerel 《Molecules (Basel, Switzerland)》2022,27(24)
Preferential enrichment (PE) is a crystallization process, starting from either a racemic of slightly enantio-enriched solution (ca. +5%) that results in a high enantiomeric excess in the liquid phase (>+90%ee) and a slight opposite excess in the deposited crystals (−2 to −5%ee). The mechanism(s) of this symmetry-breaking phenomenon is (are) still a matter of debate since it eludes rationalization by phase diagram formalism. In this publication, we thoroughly reinvestigate the PE phenomenon of arginine fumarate by using a new approach: the process is monitored by introducing isotopically labeled arginine enantiomers into the crystallization medium to better understand the mass exchanges during crystallization. These experiments are supported by chiral HPLC-MS/MS. This study permits re-evaluating the criteria that were thought mandatory to perform PE. In particular, we show that PE occurs by a continuous exchange between the solution and the crystals and does not require the occurrence of a solvent-mediated solid–solid phase transition. 相似文献
77.
Carolyn Puglisi Renata Ristic Jamie Saint Kerry Wilkinson 《Molecules (Basel, Switzerland)》2022,27(22)
Where vineyard exposure to bushfire smoke cannot be avoided or prevented, grape and wine producers need strategies to transform smoke-affected juice and wine into saleable product. This study evaluated the potential for spinning cone column (SCC) distillation to be used for the remediation of ‘smoke taint’. Compositional analysis of ‘stripped wine’ and condensate collected during SCC treatment of two smoke-tainted red wines indicated limited, if any, removal of volatile phenols, while their non-volatile glycoconjugates were concentrated due to water and ethanol removal. Together with the removal of desirable volatile aroma compounds, this enhanced the perception of smoke-related sensory attributes; i.e., smoke taint intensified. Stripped wines also became increasingly sour and salty as ethanol (and water) were progressively removed. A preliminary juice remediation trial yielded more promising results. While clarification, heating, evaporation, deionization and fermentation processes applied to smoke-tainted white juice gave ≤3 µg/L changes in volatile phenol concentrations, SCC distillation of smoke-tainted red juice increased the volatile phenol content of condensate (in some cases by 3- to 4-fold). Deionization of the resulting condensate removed 75 µg/L of volatile phenols, but fermentation of reconstituted juice increased volatile phenol concentrations again, presumably due to yeast metabolism of glycoconjugate precursors. Research findings suggest SCC distillation alone cannot remediate smoke taint, but used in combination with adsorbents, SCC may offer a novel remediation strategy, especially for tainted juice. 相似文献
78.
F. Feigl und Lydia v. Tustanowska 《Fresenius' Journal of Analytical Chemistry》1925,66(4-5):176-177
Ohne Zusammenfassung 相似文献
79.
Ohne Zusammenfassung 相似文献
80.
Inhibition of corrosion of commercial mild steel in presence of tetrazole derivatives in acid medium
V. Violet Dhayabaran I. Sharmila Lydia J. Princy Merlin P. Srirenganayaki 《Ionics》2004,10(1-2):123-125
The inhibitive influence of tetrazole derivatives namely, 1-(91-acridinyl)-5-(4′-aminophenyl) tetrazole, 1-(9′-acridinyl)-5-(4′-hydroxy phenyl) tetrazole and 1-(9′-acridinyl)-5-(4′-chlorophenyl)
tetrazole on the corrosion of commercial mild steel in 1 N hydrochloric acid medium was studied by weight loss method. The
monolayer adsorption has been confirmed by fitting the data to the Langmuir adsorption isotherm. Weight loss studies have
been carried out at 303K, 318K and 333K. Thermodynamic parameters like heat of adsorption, activation energy and free energy
change have been calculated. The maximum inhibition of efficiency of tetrazole derivatives, 1-(9′-acridinyl)-5-(4′-amoinophenyl)
tetrazole, 1-(9′acridinyl)-5-(4′-hydroxyphenyl) tetrazole and 1-(9′-acridinyl)-5-(4′-Chlorphenyl) tetrazole was found to be
60.59%, 89.00% and 92.74, respectively.
Paper presented at the 2nd International Conference on Ionic Devices, Anna University, Chennai, India, Nov. 28–30, 2003. 相似文献