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Abstract  

Humic acids (HAs) extracted from soils developed under two Norwegian spruce (Picea abies, (L.) Karst) subalpine forests of northern Italy were characterized using chemical, thermal (TG-DTA) and spectroscopic (DRIFT) analyses. The samples were taken from five sites which differed in orientation (northern and southern exposure) and vegetal cover at different old age: grassland, regeneration, immature and mature stands. In general, the thermal patterns of HAs were similar (three exothermic reactions appeared around at 300, 400 and 500C) in both sites in grasslands and regeneration while a considerable modification appeared in HA from stands of different age at northern and southern exposure site. DRIFT spectroscopy confirmed the differences observed through TG-DTA analysis. In particular the main structural changes were ascribed to modification of carbonyl group and of CH stretching in aliphatic components in each HAs from different sites.

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, J. ( 2008 ) Climatic systematic factors assessment on sprinkler irrigation system wind drift and evaporation losses . Science and Technology of Agriculture 22 Naseri , A

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920 924 Kimura T, Arimitsu T, Matsuura R, Yunoki T, Yano T: Effect of blood volume in inactive muscle on heart rate drift during prolonged exercise. Adv. Exerc. Sports Physiol

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(atmospheric pressure and 100 °C) than reported in the literature [ 4 – 12 ] with a view to analyze the adsorbed species formed in the first step of the phenol adsorption-oxidation on the Mn–Ce catalyst by DRIFTS spectroscopy. Experimental

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Summary This note is about an occupation time identity derived in [14] for reflecting Brownian motion with drift \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $-\mu<0,$ \end{document} RBM(\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $-\mu$ \end{document}), for short. The identity says that for RBM(\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $-\mu$ \end{document}) in stationary state
\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $$(I^{+}_t, I^{-}_t) \overset{(d)}{=} (t-G_t,D_t-t),\qquad t\in \mathbb{R},$$ \end{document}
where \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $G_t$ \end{document} and \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $D_t$ \end{document} denote the starting time  and the ending time, respectively, of an excursion from 0 to 0 (straddling \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $t$ \end{document}) and \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $I^{+}_t$ \end{document} and \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $I^{-}_t$ \end{document} are the occupation times above and below, respectively, of the observed level at time \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $t$ \end{document} during the excursion. Due to stationarity, the common distribution does not depend on \documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $t.$ \end{document}  In fact, it is proved in [9] that the identity is true, under some assumptions, for all recurrent diffusions and stationary processes. In the null recurrent diffusion case the common distribution is not, of course, a probability distribution. The aim of this note is to increase understanding of the identity by studying the  RBM(\documentclass{aastex} \usepackage{amsbsy} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{bm} \usepackage{mathrsfs} \usepackage{pifont} \usepackage{stmaryrd} \usepackage{textcomp} \usepackage{upgreek} \usepackage{portland,xspace} \usepackage{amsmath,amsxtra} \pagestyle{empty} \DeclareMathSizes{10}{9}{7}{6} \begin{document} $-\mu$ \end{document}) case via Ray--Knight theorems.
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Abstract  

In this work, we describe and evaluate the use of the Fourier transform infra red (FTIR) spectroscopy in DRIFT mode (diffuse reflectance infra red Fourier transform) in an environmental device to follow the functional evolution of cellulose during thermal treatments. The potentialities (and difficulties) of the technic are given.

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Abstract  

Different metal ion-exchanged montmorillonite based clay catalysts (Mn+-mont; Mn+ = Al3+, Fe3+, Cr3+, Zn2+, Ni2+, Mn2+, Cu2+ and H+) were prepared and characterized by various physico-chemical techniques. The clay catalysts were evaluated for the esterification of propionic acid with p-cresol. Our DRIFTS (Diffuse Reflectance Infrared Fourier Transform Spectroscopy) study of the catalysts treated with propionic acid supported the very well established mechanism of esterification. Furthermore, the esterification was conducted in the presence of different solvents such as benzene, toluene, o-xylene and 1,4-dioxane. Interestingly, the reaction carried out in the presence of 1,4-dioxane did not yield any product. The role played by this specific solvent in preventing the formation of ester product has been investigated by DRIFTS study involving catalyst and solvent interaction.

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Abstract  

Giving a generalization of Berkes and Horvth (2003), we consider the Euclidean norm of vector-valued stochastic processes, which can be approximated with a vector-valued Wiener process having a linear drift. The suprema of the Euclidean norm of the processes are not far away from the norm of the processes at the right most point. We also obtain an approximation for the supremum of the weighted Euclidean norm with a Wiener process.

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Abstract  

In order to explore the influence of CeO2 on the structure and surface characteristics of molybdena, an investigation was undertaken by using N2 adsorption (BET method), thermal analysis and in-situ diffuse reflectance infrared (DRIFT) techniques. In this work, the Mo/CeO2 and Ce-Mo/Al2O3 samples were prepared by impregnation and co-precipitation methods with high Mo loadings. Combining the results one may notice that the presence of ceria led to the increase of polymerized surface Mo species so as to forming Mo-O-Ce linkages besides the formation of coupled O=Mo=O bonds indicative of polymeric MoO3. From thermal analysis, it can be inferred that Mo/Al2O3 is the thermally most stable material in the temperature range used in the experiment (up to 900°C), whereas Ce-Mo/Al2O3 and Mo/CeO2 samples undergo morphological modifications above 700°C resulting in lattice defects, which motivate the mobility of Mo and Ce ions and thus enhance the possibility of interaction between them. Additionally, their activity towards CO adsorption needs reduced ceria and molybdena containing coordinatively unsaturated sites (CUS), oxygen vacancies and hydroxyl groups to form various carbonate species.

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Acta Physiologica Hungarica
Authors: K. Kumagai, K. Kurobe, H. Zhong, J. Loenneke, R. Thiebaud, F. Ogita, and Takashi Abe

977 981 Coyle EF, Gonzalez-Alonso J: Cardiovascular drift during prolonged exercise: new perspectives. Exerc. Sports Sci. Rev. 29, 88–92 (2001

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