Description of a Sulfitobacter Strain and Its Extracellular Cyclodipeptides

A marine bacterium M44 was separated from 30 m deep seawater in the East China Sea (26° 28.3′ N 122° 29.0′ E) in 2006. 16S rDNA gene sequence comparison showed that the strain M44 was a member of the genus Sulfitobacter and highly similar to KMM 3554T. A series of experiments demonstrated that this strain M44 had many distinctive characteristics: its cells were gram-negative and mesophilic; its colonies were slightly yellowish, round, convex, and smooth; and it could grow at 10–28°C, pH 6.0–10.0, and in the presence of 0–12.5% (w/v) NaCl; the optimum growth conditions were 25°C and pH 7.0, and the optimum Na+ concentration was 2.5%. In addition, strain M44 contained 18 : 1 ω7c, 11 methyl 18 : 1 ω7c and 16 : 0 fatty acids as major fatty acids, and the genomic DNA G+C content was 58.04 mol%. According to our results of the secondary metabolites, six cyclodipeptides were isolated from the strain M44, which were Cyclo (Val-Leu), Cyclo (Phe-Val), Cyclo (Phe-Leu), Cyclo (Leu-Ile), Cyclo (Phe-Ile), and Cyclo (Trp-Pro). It is the first study of secondary metabolites isolated from this genus

Characterization of CoTiO3 Nanocrystallites Prepared by Homogeneous Precipitation Method

Nanocrystalline cobalt titanate (CoTiO3) has been synthesized from a well-mixed precursor. The precursor was prepared by a homogeneous precipitation method, in which urea was used as the precipitator. The as-synthesized sample is a mixture of CoTiO3 and rutile nanocrystallites with mean sizes of around 50 nm. It strongly absorbs visible light in the wavelength range of 500-690 nm besides ultraviolet light (wavelength < 370 nm). We found the synthetic CoTiO3 is a semiconducting material with a direct band gap of 2.53 eV. The green CoTiO3 has two absorbance peaks at the wavelengths of 537 and 606 nm, which correspond to the photon energies of 2.31 and 2.05 eV, respectively. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3195

Magnetic Borophenes from an Evolutionary Search

A computational methodology based on ab initio evolutionary algorithms and spin-polarized density functional theory was developed to predict two-dimensional magnetic materials. Its application to a model system borophene reveals an unexpected rich magnetism and polymorphism. A metastable borophene with nonzero thickness is an antiferromagnetic semiconductor from first-principles calculations, and can be further tuned into a half-metal by finite electron doping. In this borophene, the buckling and coupling among three atomic layers are not only responsible for magnetism, but also result in an out-of-plane negative Poisson\u27s ratio under uniaxial tension, making it the first elemental material possessing auxetic and magnetic properties simultaneously