翻訳と辞書 Words near each other ・ Bet Mishpachah Cemetery ・ Bet naar de Olympiade ・ BET Networks ・ Bet ng Bayan ・ BET Nightly News ・ Bet Nissim Synagogue ・ Bet on Black ・ Bet on the Saint ・ Bet on Your Baby ・ BET Presents Chris Brown ・ BET Presents Kelly Rowland ・ Bet Shemesh Blue Sox ・ Bet Shira Congregation ・ BET Style ・ Bet That ・ BET theory ・ Bet Twice ・ Bet Tzedek Legal Services – The House of Justice ・ BET UK ・ Bet v I allergen ・ Bet Yaakov Synagogue ・ Bet You Can't Do It Like Me ・ Bet You Think I'm Lonely ・ Bet Your Heart on Me ・ Bet'cha Gonna Need My Lovin' ・ Bet'oul Eih ・ BET's Listening Party ・ BET's Top 25 ・ Bet, Queen of Jordan ・ BET-10 Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク BET theory ： ウィキペディア英語版 BET theory Brunauer–Emmett–Teller (BET) theory aims to explain the physical adsorption of gas molecules on a solid surface and serves as the basis for an important analysis technique for the measurement of the specific surface area of a material. In 1938, Stephen Brunauer, Paul Hugh Emmett, and Edward Teller published the first article about the BET theory in the Journal of the American Chemical Society. The BET theory refers to multi layer adsorption, and usually adopts non-corrosive gases (like nitrogen, argon, carbon dioxide, etc.) as adsorbates to determine the surface area data. ==Concept== The concept of the theory is an extension of the Langmuir theory, which is a theory for monolayer molecular adsorption, to multilayer adsorption with the following hypotheses: # gas molecules physically adsorb on a solid in layers infinitely; # there is no interaction between each adsorption layer; and # the Langmuir theory can be applied to each layer. The resulting BET equation is :$\backslash frac\; \backslash right\; )\; -1\; \backslash right\; )\}\; =\; \backslash frac\; \backslash left\; (\; \backslash frac\; \backslash right\; )\; +\; \backslash frac,\; \backslash qquad\; (1)$ where $p$ and $p\_0$ are the equilibrium and the saturation pressure of adsorbates at the temperature of adsorption, $v$ is the adsorbed gas quantity (for example, in volume units), and $v\_\backslash mathrm$ is the monolayer adsorbed gas quantity. $c$ is the ''BET constant'', :$c\; =\; \backslash exp\backslash left(\backslash frac\backslash right),\; \backslash qquad\; (2)$ where $E\_1$ is the heat of adsorption for the first layer, and $E\_\backslash mathrm$ is that for the second and higher layers and is equal to the heat of liquefaction. Equation (1) is an adsorption isotherm and can be plotted as a straight line with $/)\; -1\; )\}$ on the y-axis and $\backslash phi=/$ on the x-axis according to experimental results. This plot is called a ''BET plot''. The linear relationship of this equation is maintained only in the range of . The value of the slope $A$ and the y-intercept $I$ of the line are used to calculate the monolayer adsorbed gas quantity $v\_\backslash mathrm$ and the BET constant $c$. The following equations can be used: :$v\_m\; =\; \backslash frac\backslash qquad\; (3)$ :$c\; =\; 1+\backslash frac.\backslash qquad\; (4)$ The BET method is widely used in surface science for the calculation of surface areas of solids by physical adsorption of gas molecules. The total surface area $S\_\backslash mathrm$ and the specific surface area $S\_\backslash mathrm$ are given by :$S\_\backslash mathrm\; =\; \backslash frac,\; \backslash qquad\; (5)$ :$S\_\backslash mathrm\; =\; \backslash frac,\; \backslash qquad\; (6)$ where $v\_\backslash mathrm$ is in units of volume which are also the units of the molar volume of the adsorbate gas, $N$ is Avogadro's number, $s$ the adsorption cross section of the adsorbing species, $V$ the molar volume of the adsorbate gas, and $a$ the mass of the solid sample or adsorbent. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「BET theory」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.