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Bacterial cellulose (BC) is a kind of nanobiomaterial for tissue engineering. How the nanoscale structure of BC affects skin wound repair is unexplored. Here, the hierarchical structure of BC films and their different effects on skin wound healing were studied both in vitro and in vivo. The bottom side of the BC film had a larger pore size, and a looser and rougher structure than that of the top side. By using a microfluidics-based in vitro wound healing model, we revealed that the bottom side of the BC film can better promote the migration of cells to facilitate wound healing. Furthermore, the full-thickness skin wounds on Wistar rats demonstrated that, compared with gauze and the top side of the BC film, the wound covered by the bottom side of the BC film showed faster recovery rate and less inflammatory response. The results indicate that the platform based on the microfluidic chip provide a rapid, reliable, and repeatable method for wound dressing screening. As an excellent biomaterial for wound healing, the BC film displays different properties on different sides, which not only provides a method to optimize the biocompatibility of wound dressings but also paves a new way to building heterogeneous BC-based biomaterials for complex tissue engineering. [ABSTRACT FROM AUTHOR]

Abstract: The anisotropic g factors g i (i=x, y, z ) for the six-fold coordinated orthorhombic Cu2+(1) site in YBa1.9Na0.1Cu3O7−δ and the five-fold coordinated tetragonal Cu2+(2) site in YBa2Cu3O7−δ are theoretically studied from the perturbation formulas of the g factors for a 3d9 ion in orthorhombically and tetragonally elongated octahedra, respectively. The orthorhombic (or tetragonal) field parameters are obtained using the superposition model and the local structures of the Cu2+ sites. In view of covalency, the contributions from the ligand orbital and spin-orbit coupling interactions are taken into account. For the Cu2+(1) site in YBa1.9Na0.1Cu3O7−δ, the axial anisotropy Δg[=g z −(g x −g y )/2] may be ascribed to the moderate (about 3%) elongation of the Cu–O distance along c axis, while the perpendicular anisotropy δg(=g x −g y ) can be characterized by the planar bond length deviation difference δR(≈0.083Å) in the perpendicular (ab) plane. However, for the Cu2+(2) site in YBa2Cu3O7−δ, the anisotropy Δg(=g ||−g ⊥) is illustrated by the significant elongation of the [CuO5]8− cluster along c axis with about 25% longer axial Cu–O distance than the four planar ones. The theoretical g factors are in good agreement with the experimental data. [Copyright &y& Elsevier]

The article presents information on properties and structure of barium ferrites and discusses the method of synthesis of M-type hexagonal barium ferrite powders using sol-gel processes. It mentions ferromagnetic properties of barium ferrites and states that these ferrites contain hexagonal close-packed structure. It mentions the methodology of sol-gel method conducted using thermal gravimetric analysis and differential scanning calorimetry.

E-(4- β-D-Allopyranosyloxyphenyl)-1-(4-substituted phenyl)propenone derivatives ( 1a–g) have been synthesized by the Claisen-Schmidt condensation of helicid with 4-substituted acetophenone using 10% NaOH aqueous solution as a catalyst. 6 H-2-Amino-4-aryl-6-(4- β-D-allopyranosyloxyphenyl)-1,3-thiazine ( 2a–g) were synthesized by the 1,4-Michael reaction of 1a–g with thiourea. The structures of all the new products were established by 1H NMR, IR, and MS spectroscopy. Compound 2b (200 mg·kg–1) showed better sedative-hypnotic activity, so further modification of helicid should be worthwhile. [ABSTRACT FROM AUTHOR]

Here we report the first unambiguous identification of the chemical structures of the precursor species involving metal (Au and Ag) ions and Te-containing ligands in the Brust-Schiffrin syntheses of the respective metal nanoparticles, through which the different reaction pathways involved are delineated. [ABSTRACT FROM AUTHOR]

The article presents a study which synthesized the first example of a chain structure based on a tetranuclear MnII cluster. The synthesis of the title compound is described in detail. It illustrates the distortions of manganese (Mn) ion and oxygen (O) atoms. Also noted are review of related studies and the importance of chain structures in coordination chemistry and materials chemistry.

Coordination of unsaturated [In(amine)]3+ onto indium telluride structure, where the complex ion has higher positive charge, not only forms an organic-inorganic hybrid polymeric structure, but also offers an indium telluride with positive charge. Based on this strategy, cationic networks of metal chalcogenide may be expected. [ABSTRACT FROM AUTHOR]

A novel chlorinated briarane, fragilide E (1), which possesses an unprecedented 20-acetoxy group, was isolated from the gorgonian coral Junceella fragilis. The structure of 1 was elucidated by spectroscopic methods. [ABSTRACT FROM AUTHOR]

In the title compound, {[Cu(C14H8O4)(C4H6N2)2]·2H2O} n, each CuII atom is four-coordinated by two N atoms from two 2-methyl-1 H-imidazole (mi) ligands and two O atoms from two biphenyl-2,2′-dicarboxylate (dpdc) anions in a distorted square-planar coordination environment. Each dpdc ligand bridges two neighboring CuII atoms in a bis-monodentate mode, forming a zigzag chain along the b axis. These chains are decorated with mi ligands alternately on the two sides. O—H...O and N—H...O hydrogen bonds involving the water molecules link the chains together, forming a supramolecular structure. [ABSTRACT FROM AUTHOR]

The title compound, [Sn4(CH3)8(C6H5N2O2)4O2]·6H2O, is a hydrated cluster containing four Sn atoms, built up by inversion symmetry around the central Sn2O2 ring. The Sn-atom coordination geometry might be regarded as very distorted SnO3C2 trigonal–bipyramidal or possibly as grossly distorted SnO3C2N octahedral. All the cluster non-H atoms, with the exception of the Sn-bonded methyl groups, lie on a mirror plane. Two of the water-molecule O atoms have m site symmetry; the other occupies a twofold rotation axis. [ABSTRACT FROM AUTHOR]

In the title complex, [Sn(C7H6Cl)2(C7H13N2S2)Cl], the Sn atom is five-coordinate in a trigonal–bipyramidal geometry. One Sn—S bond is markedly longer than the other for the chelating dithiocarbamate ligand. [ABSTRACT FROM AUTHOR]

Chemical structures of two-dimensional (2D) nanosheet can effectively control the properties thus guiding their applications. Herein, we demonstrate that carbon nitride nanosheets (CNNS) with tunable chemical structures can be obtained by exfoliating facile accessible bulk carbon nitride (CN) of different polymerization degree. Interestingly, the electrochemiluminescence (ECL) properties of as-prepared CNNS were significantly modulated. As a result, unusual changes for different CNNS in quenching of ECL because of inner filter effect/electron transfer and enhancement of ECL owing to catalytic effect were observed by adding different metal ions. On the basis of this, by using various CNNS, highly selective ECL sensors for rapid detecting multiple metal-ions such as Cu2+, Ni2+, and Cd2+ were successfully developed without any labeling and masking reagents. Multiple competitive mechanisms were further revealed to account for such enhanced selectivity in the proposed ECL sensors. The strategy of preparing CNNS with tunable chemical structures that facilely modulated the optical properties would open a vista to explore 2D carbon-rich materials for developing a wide range of applications such as sensors with enhanced performances. [ABSTRACT FROM AUTHOR]

In the title compound, C12H12ClN5O3S, the pyrazole ring and the benzene ring are approximately coplanar. The mean plane of the pyrazole ring makes a dihedral angle of 12.82 (13)° with the mean plane of the benzene ring. The crystal packing is stabilized by intramolecular N—H...O and intermolecular N—H...O and N—H...N hydrogen bonds. [ABSTRACT FROM AUTHOR]

Abstract: Five (1–5) ent-kaurane diterpenoids and 17 other known ones, were isolated from the leaves and stems of Isodon sinuolata. Their structures were determined on the basis of spectroscopic methods including 1D and 2D NMR spectroscopic analysis. All compounds were evaluated for cytotoxicity against a small panel of cell lines. Some compounds exhibited significant cytotoxicity. [Copyright &y& Elsevier]

Abstract: Schilancidilactones A (1) and B (2), two novel tetranortriterpenoids possessing an unprecedented skeleton, have been isolated from the stems of Schisandra lancifolia. Their structures were elucidated on the basis of extensive spectroscopic analysis. The relative configurations of 1 were further determined by single-crystal X-ray crystallography. Compounds 1 and 2 were tested for their cytotoxicity against four tumor cell lines NB4, A549, SH-SY5Y, and PC-3, and compound 1 was further tested for its anti-HIV-1 activity. [Copyright &y& Elsevier]

The article discusses a study which develops a tandem Michael addition/ylide epoxidation for the rapid creation of highly functionalized cyclohexadiene epoxide skeletons with three sterocenters. The study investigated the intramolecular version of the tandem reaction. It is showed that the tandem reaction could access to highly functionalized cyclohexadiene epoxide derivatives with excellent diastereoselectivity and chemoselectivity.