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This essay claims that contemplative classroom practices can cultivate "kairotic" composure, which is an attunement to the dual aspects of the rhetorical concept of "Kairos"--a sense of timelessness or deep presence, and a sense for saying or writing the right word in the right moment. While theorists of contemplative writing pedagogy have helped ground the first aspect of "kairos", current theorists of "kairos" have grown our understanding of the second. This essay unites both streams of scholarship with a cultural rhetorics framework that foregrounds storying relationships in time and place. We then share classroom exercises that can advance such "kairotic composure" across disciplines, increasing presence-based learning responsive to relationships in time and place.

A thorough experimental and computational study has been carried out to elucidate the mechanistic reasons for the high volumetric uptake of methane in the metal-organic framework Cu3(btc)2 (btc(3-) = 1,3,5-benzenetricarboxylate; HKUST-1). Methane adsorption data measured at several temperatures for Cu3(btc)2, and its isostructural analogue Cr3(btc)2, show that there is little difference in volumetric adsorption capacity when the metal center is changed. In situ neutron powder diffraction data obtained for both materials were used to locate four CD4 adsorption sites that fill sequentially. This data unequivocally shows that primary adsorption sites around, and within, the small octahedral cage in the structure are favored over the exposed Cu(2+) or Cr(2+) cations. These results are supported by an exhaustive parallel computational study, and contradict results recently reported using a time-resolved diffraction structure envelope (TRDSE) method. Moreover, the computational study reveals that strong methane binding at the open metal sites is largely due to methane-methane interactions with adjacent molecules adsorbed at the primary sites instead of an electronic interaction with the metal center. Simulated methane adsorption isotherms for Cu3(btc)2 are shown to exhibit excellent agreement with experimental isotherms, allowing for additional simulations that show that modifications to the metal center, ligand, or even tuning the overall binding enthalpy would not improve the working capacity for methane storage over that measured for Cu3(btc)2 itself.

This essay claims that contemplative classroom practices can cultivate kairotic composure, which is an attunement to the dual aspects of the rhetorical concept of Kairos—a sense of timelessness or deep presence, and a sense for saying or writing the right word in the right moment. While theorists of contemplative writing pedagogy have helped ground the first aspect of kairos, current theorists of kairos have grown our understanding of the second. This essay unites both streams of scholarship with a cultural rhetorics framework that foregrounds storying relationships in time and place. We then share classroom exercises that can advance such kairotic composure across disciplines, increasing presence-based learning responsive to relationships in time and place. [ABSTRACT FROM AUTHOR]

An essay is presented which focuses on the Indianapolis Resolution in Indianapolis, Indiana which calls the professional organizations and their members to commit actively to labor equity. Topics include the argument that the current moment both invites and demands field's participation in labor justice efforts, and the process of drafting the Indianapolis Resolution stated to provide a rationale for its three-part call for institutional compliance, disciplinary pedagogy, and labor research.

The stable, guest-free crystal form of the simple molecular cavitand, Me,H,SiMe2, is shown to be intrinsically porous, possessing discrete, zero-dimensional (0D) pores/microcavities of about 28 Å3. The incollapsible 0D pores of Me,H,SiMe2 have been exploited for the enclathration and room temperature (and higher) confinement of a wide range of small gases. Over 20 isostructural x(gas/guest)@Me,H,SiMe2 (x ≤ 1) clathrates (guest = H2O, N2, Ar, CH4, Kr, Xe, C2H4, C2H6, CH3F, CO2, H2S, CH3Cl, CH3OCH3, CH3Br, CH3SH, CH3CH2Cl, CH2Cl2, CH3I, CH3OH, BrCH2Cl, CH3CH2OH, CH3CN, CH3NO2, I2), and a propyne clathrate (CH3CCH@Me,H,SiMe2.2CHCl3), have been prepared and characterized, and their single crystal structures determined. Gas enclathration is found to be highly selective for gases that can be accommodated by the predefined, though slightly flexible 0D pore. The structure determinations provide valuable insight, at subangstrom resolution, into the factors that govern inclusion selectivity, gas accommodation, and the kinetic stability of the clathrates, which has been probed by thermal gravimetric analysis. The activation (emptying) of several clathrates (guest = H2O, N2, CO2, Kr, CH3F) is shown to occur in a single-crystal-to-single-crystal (SC → SC) fashion, often requiring elevated temperatures. Akin to open pore materials, water vapor and CO2 gas are shown to be taken up by single crystals of empty Me,H,SiMe2 at room temperature, but sorption rates are slow, occurring over weeks to months. Thus, Me,H,SiMe2 exhibits very low, but measurable, gas permeability, despite there being no obvious dynamic mechanism to facilitate gas uptake. The unusually slow exchange kinetics has allowed the rates of gas (water vapor and CO2) sorption to be quantified by single crystal X-ray diffraction. The data are well fit to a simple three-dimensional diffusion model. [ABSTRACT FROM AUTHOR]

A thorough experimental and computational study has been carried out to elucidate the mechanistic reasons for the high volumetric uptake of methane in the metal-organic framework Cu3(btc)2 (btc3- = 1,3,5-benzenetricarboxylate; HKUST-1). Methane adsorption data measured at several temperatures for Cu3(btc)2, and its isostructural analogue Cr3(btc)2, show that there is little difference in volumetric adsorption capacity when the metal center is changed. In situ neutron powder diffraction data obtained for both materials were used to locate four CD4 adsorption sites that fill sequentially. This data unequivocally shows that primary adsorption sites around, and within, the small octahedral cage in the structure are favored over the exposed Cu2+ or Cr2+ cations. These results are supported by an exhaustive parallel computational study, and contradict results recently reported using a time-resolved diffraction structure envelope (TRDSE) method. Moreover, the computational study reveals that strong methane binding at the open metal sites is largely due to methane-methane interactions with adjacent molecules adsorbed at the primary sites instead of an electronic interaction with the metal center. Simulated methane adsorption isotherms for Cu3(btc)2 are shown to exhibit excellent agreement with experimental isotherms, allowing for additional simulations that show that modifications to the metal center, ligand, or even tuning the overall binding enthalpy would not improve the working capacity for methane storage over that measured for Cu3(btc)2 itself. [ABSTRACT FROM AUTHOR]