Pronounced Visible Light Photocatalytic Activity Obtained from Coupling of TiO2 with Metal Organic Macromolecule

In this work, a new catalyst TiO2@MOM has been successfully synthesized by coupling TiO2 with metal organic macromolecule (MOM) through hydrothermal-solvothermal two-step process. Having a high visible photocatalytic activity considerably superior to that of single TiO2, the fabrication of TiO2@MOM should provide a new way of upgrading the TiO2–based catalyst.

Characterisation of yeast and filamentous fungi from Brøggerbreen glaciers, Svalbard

ABSTRACTCryoconite holes have ecological and biotechnological importance. This article presents results on culturable cryophilic yeasts and filamentous fungi isolated from cryoconite holes at Austre and Vestre Brøggerbreen glaciers, Svalbard. Based on DNA sequence data, these were identified asRhodotorulasp.,Thelebolussp., andArticulospora tetracladia. Amongst these,Articulospora tetracladia(88.7–89.4% gene similarity with 5.8S rDNA) is a novel species, yet to be described. Filamentous fungusArticulosporasp. Cry-FB1 and Cry-FB2, expressed high amylase, cellulase, lipase and protease activities while yeastRhodotorulasp. Cry-FB3 showed high amylase and cellulase activity.Thelebolussp. Cry-YB 240 and Cry-YB 241 showed protease and urease activities. The effects of temperature, and salt on the growth of the cultures were studied. Optimum temperature of growth was on 10ºC at pH 7.0. Filamentous fungi and yeast in the cryoconite holes possibly drive the process of organic macromolecule degradation through cold-adapted enzyme secretion, thereby assisting in nutrient cycling in these supraglacial environments. Further, these cryophilic fungi, due to their enzyme producing ability, may provide an opportunity for biotechnological research in the Arctic.

A Mercury Free Method for the Determination of Chemical Oxygen Demand of the Sample with High Salinity and Organic Macromolecule

An improved method for the determination of chemical oxygen demand (COD) is presented. This method is based on the standard method but using silver sulfate as a masking agent for the chloride and using the microwave for the digestion. The method gives tiny errors when the chloride of the samples increases from 606.6 mg/L to more than 30,000 mg/L. The method applies to the samples containing macromolecules and give better results when the sample is prehydrolysed.

Research Progress of Coal Flocculat in Recent Years

Flocculant put in coal slime water is an important method to improve the sedimentation effect of fine coal. This paper analyses the application type and characteristic of coal flocculants, and the research progress of coal flocculants in recent years. The results show that a large number of coal inorganic electrolyte flocculant and organic macromolecule flocculant will lead to environment pollution and harming people’s health. But coal microorganism flocculant not only has characteristic of traditional coal flocculating agent, but also has many special characteristic such as biodegradation. The coal microorganiam flocculants will make a great development and application in the future.

Preparation of Hydrophobic Magnesium Hydroxide Nanoparticles by Oleic Acid and Polystyrene-Grafting Surface Modification

In order to avoid their agglomeration and incompatibility with polymer matrix, hydrophobic magnesium hydroxide nanoparticles were obtained by means of grafting polystyrene (PS) onto the surface of nanoparticles after oleic acid (OA) modification. Firstly, the functional double bonds were conducted on the surface of blank magnesium hydroxide nanoparticles by OA modification, and then, PS was grafted on the surface of OA-modified magnesium hydroxide. The microstructure of resultant sample was characterized by TEM, TGA and FTIR. In the meantime, the compatibility with some organic solutions was determined by dispersibility evaluation. The results show that the organic macromolecule PS could be successfully grafted on the surface of OA-modified magnesium hydroxide nanoparticles, and the dispersibility and the compatibility of nanoparticles greatly improved in organic phase.

Thermochemolysis of the Murchison meteorite: identification of oxygen bound and occluded units in the organic macromolecule

An organic macromolecular residue, prepared from the Murchison meteorite by treatment with hydrofluoric and hydrochloric acids, was subjected to online thermochemolysis with tetramethylammonium hydroxide (TMAH). The most abundant compound released by thermochemolysis was benzoic acid. Other abundant compounds include methyl and dimethyl benzoic acids as well as methoxy benzoic acids. Short chain dicarboxylic acids (C4–8) were also released from the organic macromolecule. Within the C1 and C2 benzoic acids all possible structural isomers are present reflecting the abiotic origin of these units. The most abundant isomers include 3,4-dimethylbenzoic acid (DMBA), 3,5-DMBA, 2,6-DMBA and phenylacetic acid. Thermochemolysis also liberates hydrocarbons that are not observed during thermal desorption; these compounds include naphthalene, methylnaphthalenes, biphenyl, methylbiphenyls, acenaphthylene, acenaphthene, phenanthrene, anthracene, fluoranthene and pyrene. The lack of oxygen containing functional groups in these hydrocarbons indicates that they represent non-covalently bound, occluded molecules within the organic framework. This data provides a valuable insight into oxygen bound and physically occluded moieties in the Murchison organic macromolecule and implies a relative order of synthesis or agglomeration for the detected organic constituents.