27th International Chugaev Conference on Coordination Chemistry (October 2—6, 2017, Nizhny Novgorod)

Russian Chemical Bulletin -     

Artificial Neural Networks Applied to Gas Mixture Analysis

1IntroduedonToanalyZehydrocarbongasndxtureS,asyStemconsistingofasuhablemulti-sereorarray,anaogUe-to-digitaconVerter(ADC)andacoInPuterfOrmulti-variatecalibrationalgorithInshasbameStablished[la].ThenonseledveandnonlinearresponsecharacteriaicsofchdricalsensorsareanirnPortantliInhaontoanalyzinmulti-coInPonatchdricamixtures.AmongthepotdriallyusefulnoulinearmAnods,anifioalneuralnfororks(ANN)arehighlypromising,mainlybecausetheANNisespedallysuitablefOrarbitrarynonlinearmaPpingbetWamsrmorres…     

4~(th) East-Asian Polymer Conference

May 28~31, 2006 Tianjin, ChinaOrganized by Institute of Polymer Chemistry, College of Chemistry Nankai University Key Laboratory of Functional Polymer Materials (Nankai University), Ministry of Education Tianjin University of Science & Technology Editorial Office of Chinese Journal of Reactive Polymers Chinese Chemical Society, Polymer Division (CCS) Sponsored by National Natural Science Foundation of China (NSFC) TEDA GOLONE Chemical Co., Ltd Call for Papers Participan…     

Effects of Applied Electric Fields on Drop—Interface and Drop—Drop Coalescence*

In this work, coalescence of a single organic or aqueous drop with its homophase at a horizontal liquid interface was investigated under applied electric fields. The coalescence time was found to decrease for aqueous drops as the applied voltage was increased, regardless of the polarity of the voltage. For organic drops, the coalescence time increased with increasing applied voltage of positive polarity and decreased with increasing applied voltage of negative polarity. Under an electric field, the coalescence time of aqueous drops decreases due to polarization of both the drop and the flat interface. The dependency of organic drop-interface coalescence on the polarity of the electric field may be a result of the negatively charged organic surface in the aqueous phase. Due to the formation of a double layer, organic drops are subjected to an electrostatic force under an electric field, which, depending on the field polarity, can be attractive or repulsive. Pair-drop coalescence of aqueous drops in the organic phase was also studied. Aqueous drop-drop coalescence is facilitated by polarization and drop deformation under applied electric fields. Without applied electric fields, drop deformation increases the drainage time of the liquid film between two approaching drops. Therefore, a decrease in the interfacial tension, which causes drop deformation, accelerates drop-drop coalescence under an electric field and inhibits drop coalescence in the absence of an electric field.     

XIII International Conference on Surface Forces June 28–July 4, 2006, Moscow, Russia

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XIII International Conference on Surface Forces June 28–July 4, 2006, Moscow, Russia     

International Conference on Liquid Crystal Polymers

Under the sponsorship of the International Union of Pure and Applied Chemistry (IUPAC)and Chinese Chemical Society, the International Conference on Liquid Crystal Polymers was heldat the Twenty-First Century Hotel, Beijing China, in 6-9 September 1994. The conference Chair-man and Secretary general were Professors Q. F. Zhou of Peking University and X. J. Wang of     

Surface modification by calcium ions—Effect on chromatographic properties of silica

Summary A liquid chromatographic method incorporating column-switching and fluorimetric detection for the determination of triamterene in untreated urine, is described. The urine samples (5 L) were directly introduced onto an Hypersil ODS-C18, 30 m (20 mm×2.1 mm I.D.) pre-column. Polar urinary compounds were removed by flushing the pre-column with water for 1 min, and the analyte was then switched onto an HP-LiChrospher RP C18,5 m (125 mm×4mm ID) analytical column using an acetonitrile/phosphate buffer gradient elution. Fluorescence detection was performed at 230 nm excitation and 430 nm emission wavelengths. The recovery of drug was 102±2% in the 0.10–20.0 g/mL concentration range, the limit of detection being 5 ng/mL. A validation of the usefulness of this procedure was accomplished by analysing urine extracts obtained from real samples.Hypersil ODS is not a product of Merck, Germany. Please give supplier (p. 5).     

Comment on “Ion Implantation Standards as a Spark Source Mass Spectrometric Surface Analysis Calibration Technique”

Abstract

While it is pleasing to note that ion implantation standards are being applied to yet another instrumental method for elemental near-surface analysis, it is unfortunate that the concept of using ion implantation for the manufacture of calibration standards has had to be re-invented. More regrettable than the (surely unintentional) omission to acknowledge earlier work^1–6 on the subject though, is the neglect of the authors to provide evidence for their assertion that “the implant dose was measured to an accuracy of better than 5%”. This would be unlikely with the ion current integration mode of dose measurement used by the authors, because significant backscattering of the very much lighter incident ¹¹B⁺ ion from the Zircaloy target in predominantly neutral form should render the dose calculation more inaccurate than this. Evidence of substantial backscattering is provided by the authors themselves in the form of the measured depth profiles of implanted ¹¹B shown in their Fig. 1, viz., extrapolation of these depth profiles into the vaccum side of the surface provides a means of estimating roughly the dose fractio lost by backscatteing. From the data the extrapolted loss fraction would appear to be not less than 5%. On the basis of other independent more direct experimental evidence⁷ it would appear that the backscattered fraction should be about 8% (taking the “equivalent” case - same reduced energy ? and mass ratio - of 500 keV ²⁴Na⁺ bombardment of Au, and adjusting it by the proportionality factor A₁ ^½/Z₁ ^? of Vukaní and Sigmund⁸). This same percentage value is also derived from both theoretical and experimental proton backscattering data provided in ref. 83. The fact that the backscattered fraction is virturally independent of dose for low concentrations of implanted ¹¹B precludes detection of this effect by comparison of dose-equivalent ion microprobe signals of 11_B used by the authors. Therefore, the statement by the authors that “the accuracy of the standards was verified using an ARL ion microprobe mass analyser (IMMA)” is unsubstantiate. At best, the IMMA measurements provide an indication that implantation-associated dose-dependent re-sputtering of implanted ¹¹B is negligible for the doses used by the authors. But this fortunate state of affairs is attributable solely to the unusually low sputtering yield for the combination boron/Zircaloy. In this connection it is important to point out that for many other combinations the fractional loss by re-sputtering of the implanted ion in the energy region under discussion is in considerable excess of 5% for the doses used by the authors; and this not take into account any possible loss inrease that may be caused by bombardment-induced radiation-enhanced diffusion towards the surface. Calculation of the minimum re-sputtering loss is possible with an algorith developed by gries^3,9.