Research on the coagulant aid effects of modified diatomite on coal microbial flocculation.

Diatomite was modified by chitosan to prepare modified diatomite, and the modified diatomite in an optimized ratio was utilized in coal bio-flocculation. The interaction behavior and flocculation mechanism of modified diatomite on coal slurry water were investigated by single factor experiments, infrared spectroscopy, Brunauer-Emmett-Teller (BET) measurements, and zeta potential measurements. The single factor experiments showed that when the amount of microbial flocculant added was 1.5 ml, the temperature of coal slurry water was 39 °C, the pH was 5, and the amount of modified diatomite was 0.2 g, after 30 min of sedimentation, the flocculation transmittance of the coal slurry water reached 84.3%. The infrared spectra showed that the -NH2 and -OH of the chitosan molecule had a polar interaction with the Si-OH bond in diatomite. The BET measurements showed that the specific surface area of diatomite was not a decisive factor affecting the flocculation effect. Zeta potential measurements indicated that the amino protonation of chitosan increased the isoelectric point (IEP) of modified diatomite. These results showed that modified diatomite has a good effect on coal bio-flocculation.

Development of a Gene Chip for the Detection of Common Pathogens Causing Urogenital Sexually Transmitted Infections / 中华皮肤科杂志

Objective To develop a gene chip for the detection of common pathogens causing urogenital sexually transmitted infections. Methods The target pathogens were divided into three groups: viruses, bacteria, and lower eukaryotes. Three pairs of universal primers were designed and applied to amplify the target genes of these different pathogens in one PCR reaction system. The gene chips were then prepared via immobilization of the specific probes onto specially treated glass slides. Finally, the labeled amplicons were hybridized with the gene chips, scanned and analyzed using computer software. Results Amplicons were detected by agarose gel electrophoresis. The fluorescence signals for specific pathogens could be recognized in the gene chips, and were identical with the positions of the specific probes. Conclusions Gene chip is a specific, sensitive and rapid method for simultaneous detection of multiple sexually transmitted infections.