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TiO2/TiOF2/{2 2 2}Ag3PO4 composite catalyst was prepared by hydrothermal method. The activity of the catalyst was investigated with tetracycline hydrochloride (TTCH) as the target pollutant. The samples were characterized by XRD, SEM, TEM, PL, BET, UV–Vis and other analytical methods. The results showed that: the compound improves the photocatalytic performance of silver phosphate; increases the specific surface area of the catalyst; reduces the forbidden band width and improves the activity under sunlight; suppresses the electron-hole recombination rate and increases the transfer efficiency of photogenerated electrons. The silver phosphate in the composite sample is in the form of tetrahedrons with exposed high-energy surfaces {2 2 2}. The degradation efficiency of 20 mg TiO2/TiOF2/Ag3PO4 composite catalyst has a catalytic rate of 86.4% for tetracycline. In the whole process, Superoxide radical ( O2−) has an important effect on the degradation activity of the composite catalyst to TTCH.

Burnett equations were originally derived in 1935 by Burnett by employing the Chapman-Enskog expansion to Classical Boltzmann equation to second order in Knudsen number Kn. Since then several variants of these equations have been proposed in the literature; these variants have differing physical and numerical properties. In this papers, we considered four such variants which are known in the literature as ‘the Original Burnett (OB) equations, the Conventional Burnett (CB)'equations, ‘the Augmented Burnett (AB)’ equations and the recently formulated by the authors ‘the Simplified Conventional (SCB) equations.’ One of the most important issues in obtaining numerical solutions of the Burnett equations is their stability under small perturbations. In this paper, we perform the linearized stability (known as the Bobylev Stability) analysis of three-dimensional Burnett equations for all the four variants (OB, CB, AB, and SCB) as far as the authors are aware for the first time in the literature on this subject. By introducing small perturbations in the steady state flow field, the trajectory curve and the variation in attenuation coefficient with wave frequency of the characteristic equation are obtained for all four variants of Burnett equations to determine their stability. The results show that the 3-D Augmented Burnett (AB) equations and the Simplified Conventional Burnett (SCB) equations are unconditionally stable under small wavelength perturbations. However, the Original Burnett (OB) and the Conventional Burnett (CB) equations are unstable when the Knudsen number becomes greater than a critical value and the stability condition worsens in 3-D when compared to the stability condition for 1-D and 2-D equations. The critical Knudsen number for 3-D OB and CB equations is 0.061 and 0.287 respectively. It should be noted that although both AB and SCB equations are unconditionally stable, SCB equations are much simpler to use numerically compared to AB equations without compromising accuracy.

Bacillus thuringiensis serovar alesti was used to control caterpillars from 1970s. Here we reported the complete genome of BGSC 4C1, the type strain of this serovar. It has a circular chromosome and six plasmids. The largest plasmid pBMB267 contains five insecticidal crystal protein genes (two copies of cry1Ae, cry1Gb, cry2Ab, and a novel cry1M-type gene) and three vegetative insecticidal protein genes (a novel binary toxin gene operon vip1-vip2 and vip3Aa). Besides, the strain also has many genes encodeing virulence factors, and some secondary metabolite biosynthetic gene clusters involved in synthesis of antimicrobial peptides and bacteriocins. In addition, there is a poly γ-glutamate synthesis gene cluster, whose product is a candidate to control inflammasome-mediated disorders and potential in many other fields.

In recent years, bacteriocins have attracted considerable interest for use as natural food preservatives against spoilage and pathogenic microorganisms. Recent studies have shown that the strains of Bacillus cereus group produce a range of highly diverse bacteriocins. In this study, we screened a large number of Bacillus cereus group strains and isolated one strain, Bacillus sp. Xin1, with antimicrobial activity against several food-borne pathogens. A novel circular bacteriocin, bacicyclicin XIN-1 (MW: 5848.1719 Da), was purified from the culture supernatant of Bacillus sp. Xin1. This bacteriocin exhibited high thermal stability, wide pH tolerance, and a wide range of antimicrobial activities against Bacillus cereus, Listeria monocytogenes, and Staphylococcus aureus, three important foodborne pathogens, as well as other pathogens. Bacicyclicin XIN-1 also inhibited the outgrowth of Bacillus cereus spores and did not show hemolysis activity. Bacicyclicin XIN-1 effectively inhibited or eliminated B. cereus ATTCC14579, S. aureus ATCC6538, and L. monocytogenes LM201 in skim milk. Our findings indicate that bacicyclicin XIN-1 has a remarkable potential for use as a natural food preservative in the food industry.

Root-knot nematodes (RKNs) which can infect almost all crops lead to huge economic losses in agriculture around the world. Unavailability of effective and environmentally friendly control of RKNs provides an opportunity to nematicidal bacteria. Fictibacillus phosphorivorans G25-29 is a gram-positive and spore-forming bacterium with nematicidal capability against root-knot nematodes and free-living nematode Caenorhabditis elegans. Here, we report the complete genome of F. phosphorivorans G25-29, containing a circular chromosome and encoding nine potential nematicidal factors which may contribute to its nematicidal activity.