Dense coordination network capable of selective CO2 capture from C1 and C2 hydrocarbons

We elucidated the specific adsorption property of CO(2) for a densely interpenetrated coordination polymer which was a nonporous structure and observed gas separation properties of CO(2) over CH(4), C(2)H(4), and C(2)H(6), studied under both equilibrium and kinetic conditions of gases at ambient temperature and pressure.     

Flavoenzyme-catalyzed atropo-selective n,c-bipyrrole homocoupling in marinopyrrole biosynthesis

Axially chiral biaryl compounds are frequently encountered in nature where they exhibit diverse biological properties. Many are biphenols that have C-C or C-O linkages installed by cytochrome P450 oxygenases that control the regio- and stereoselectivity of the intermolecular coupling reaction. In contrast, bipyrrole-coupling enzymology has not been observed. Marinopyrroles, produced by a marine-derived streptomycete, are the first 1,3'-bipyrrole natural products. On the basis of marinopyrrole's unusual bipyrrole structure, we explored its atropo-selective biosynthesis in Streptomyces sp. CNQ-418 in order to elucidate the N,C-bipyrrole homocoupling enzymology. Through a series of genetic experiments involving the discovery and heterologous expression of marinopyrrole biosynthesis genes, we report that two flavin-dependent halogenases catalyze the unprecedented homocoupling reaction.     

Size control of giant unilamellar vesicles prepared from inverted emulsion droplets

The production of giant lipid vesicles with controlled size and structure will be an important technology in the design of quantitative biological assays in cell-mimetic microcompartments. For establishing size control of giant vesicles, we investigated the vesicle formation process, in which inverted emulsion droplets are transformed into giant unilamellar vesicles (GUVs) when they pass through an oil/water interface. The relationship between the size of the template emulsion and the converted GUVs was studied using inverted emulsion droplets with a narrow size distribution, which were prepared by microfluidics. We successfully found an appropriate centrifugal acceleration condition to obtain GUVs that had a desired size and narrow-enough size distribution with an improved yield so that emulsion droplets can become the template for GUVs.     

Hybridization of sugar alcohols into brucite interlayers via a melt intercalation process

We report the preparation of organic-brucite (BR) hybrids using harmless sugar alcohols (xylitol, XYL, and sorbitol, SOR). Since XYL and SOR are solid materials at room temperature, the hybridization was investigated by comparing two separate methods, hydrothermal treatment and melt mixing. BR-sugar alcohol hybrids were successfully prepared by a melt intercalation method at 175 °C. X-ray diffraction and Fourier transform infrared spectroscopy analyses indicated that organic molecules were intercalated into the brucite layers, overcoming the barrier of hydroxyl bonds between the BR layers. Moreover, X-ray photoelectron spectroscopy and thermal analyses showed that the intercalated materials at 175 °C resulted in the formation of covalent Mg-O-C bond linkages on the interlayer surface of BR.     

Surface complexation reactions of inorganic anions on hydrotalcite-like compounds

In Qiao's previous report, only star polymers with T(g) (glass transition temperature) below 48°C were found forming homogeneous honeycomb coatings on the nonplanar substrates. The polymers with high T(g) are believed not able to duplicate nonplanar substrate due to their brittleness. This article presents a comprehensive study on the construction of macroporous polymeric films on various nonplanar substrates with static breath figure (BF) technique, using linear polymers with high T(g). Two kinds of linear polymers with high T(g), polystyrene-b-poly(acrylic acid) and polystyrene without polar end groups, are employed to prepare 3-dimensional macroporous films on different nonplanar substrates. Scanning electronic microscopy views on the side wall in addition to views in-plane prove that polymer films with BF array perfectly replicated the surface features of these substrates. The formation processes of macropores on these substrates are analyzed in detail, and it demonstrates that neither molecular topography nor T(g) of polymers is the critical factor contouring nonplanar substrate. A new hypothesis involving polymer plasticization and conformation during the solvent evaporation is formulated.     

In-beam M?ssbauer spectroscopy of 57 Mn implanted into lithium hydride

We measured the temperature dependence of ⁵⁷Fe M?ssbauer spectra obtained after ⁵⁷Mn implantation into polycrystalline LiH with an extremely low implantation dose. Density functional calculations suggested that the Fe atoms were predominantly implanted into both Li and H substitutional sites of the LiH crystal.     

Hyperslow Dynamics of Dissipative Envelope Solitons

Unconventional critical relaxations in the dynamics of envelope solitons subjected to a dissipation are predicted in the framework of adiabatic approximation. The degree of “slowness” in the critical relaxation process is controllable either through the loss compensation with gain or through the modulation of the magnitude of nonlinear absorption.     

Calorimetric study of the cubic mesogen,ACBC(16)

The heat capacity of the cubic mesogen ACBC(16) was measured between 16 and 500?K by adiabatic calorimetry. As well as the known condensed phases, a new crystalline phase was found to undergo a glass transition at around 165?K. Phase transitions between crystal, SmC, cubic, and isotropic liquid phases took place at 399.16, 431.15, and 474.30?K, respectively. As in the case of ANBC, a broad hump was observed in the heat capacity of the isotropic liquid phase. The first order nature of the SmC–cubic phase transition was confirmed for the first time by the observation of supercooling of the cubic phase. The broad hump in the isotropic liquid phase was shown to extend to a low temperature side if the isotropic liquid was supercooled, suggesting that the event occurring at the hump is not directly related to the cubic–isotropic liquid phase transition.