Planar Hexacoordinate Carbons: Half Covalent, Half Ionic

Indexación ScopusHerein, the first global minima containing a planar hexacoordinate carbon (phC) atom are reported. The fifteen structures belong to the CE3M3+ (E=S–Te and M=Li–Cs) series and satisfy both geometric and electronic criteria to be considered as a true phC. The design strategy consisted of replacing oxygen in the D3h CO3Li3+ structure with heavy and less electronegative chalcogens, inducing a negative charge on the C atom and an attractive electrostatic interaction between C and the alkali-metal cations. The chemical bonding analyses indicate that carbon is covalently bonded to three chalcogens and ionically connected to the three alkali metals. © 2021 Wiley-VCH GmbHhttps://onlinelibrary-wiley-com.recursosbiblioteca.unab.cl/doi/10.1002/anie.20210094

Fabrication of macro-mesoporous zirconia-alumina materials with a one-dimensional hierarchical structure

A series of one dimensional (1D) zirconia/alumina nanocomposites were prepared by the deposition of zirconium species onto the 3D framework of boehmite nanofibres formed by dispersing boehmite nanofibres into butanol solution. The materials were calcined at 773K and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), N2 adsorption/desorption, infrared emission spectroscopy (IES). The results demonstrated that when the molar percentage X=100*Zr/(Al+Zr) was > 30 %, extremely long ZrO2/Al2O3 composite nanorods with evenly distributed ZrO2 nanocrystals on the surface were formed. The stacking of such nanorods gave rise to a new kind of macroporous material without the use of any organic space filler\template or other specific technologies. The mechanism for the formation of long ZrO2/Al2O3 composite nanorods was proposed in this work

Producción de ensilados biológicos a partir de desechos de pescado, del ahumado de atún aleta amarilla (Thunnus albacares) y del fileteado de tilapia (Oreochromis sp) para alimentación de especies acuícolas

The purpose of this study was to produce silage and determine changes in the chemical and microbiological wastes smoked yellowfin tuna (Thunnus albacares) and tilapia filleting residue (Oreochromis sp), fermented with a commercial inoculum strain Lactobacillus casei Shirota. Procedures were used rustic and easy access to materials to be used as fish feed supplement. We determined the optimal ratio of molasses for fermentation, and proximate and microbiological account silage. The waste is mixed with sugar cane molasses as carbon source and commercial inoculums Lactobacillus casei strain Shirota. At the end of six days of fermentation both silages had acceptable physical and chemical characteristics. The proportions of molasses produced the highest acidification were 15 and 20% in both silage and found no significant differences (p < 0.05). Total coliforms, molds, yeasts and Salmonella sp were not present because they are inhibited by the ensiling process and that have characteristics suitable for use as a supplement in food for aquatic organisms.El propósito de este trabajo fue producir ensilados y determinar los cambios en la composición química y microbiológica de desechos del ahumado de atún aleta amarilla (Thunnus albacares) y del fileteado de tilapia (Oreochromis sp), fermentados con un inoculo comercial de Lactobacillus casei cepa Shirota. Se emplearon procedimientos rústicos y materiales de fácil acceso para utilizarse como suplemento en alimentos acuícolas. Se determinó el porcentaje de melaza óptima para la fermentación, la composición proximal y la cuenta microbiológica de los ensilados. Los desechos se mezclaron con melaza de caña de azúcar como fuente de carbono y el inoculo comercial de Lactobacillus casei cepa shirota. A los 6 días de fermentación ambos ensilados presentaron características físicas y químicas aceptables. Las proporciones de melaza que produjeron la acidificación mas alta fueron 15 y 20 % en ambos ensilados y no hubo diferencias significativas (p < 0.05). Los coliformes totales, mohos, levaduras y Salmonella sp no estuvieron presentes porque son inhibidos por el proceso de ensilaje y este tienen características adecuadas para su utilización como suplemento en alimentos para organismos acuáticos