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OBJECTIVE: This study aims to investigate the bacteria contamination on hands of funeral staffs in different positions. METHODS: Bacterial samples were collected from the hands of 105 funeral staffs in different positions (including 90 frontline staffs and 15 administrative workers) from 13 funeral parlors nationwide, and were subsequently tested by bacterium inspection. RESULTS: In total, 1783 strains of bacteria were isolated, including 1027 Gram-positive bacteria, most of which were Staphylococcus; and 756 Gram-negative bacteria, most of which were Pseudomonas. Out of the 1783 strains of bacteria, 570 pathogens and opportunistic pathogens were isolated, accounted to 31.96%. The isolated ratio of pathogens and conditional pathogens in embalmed/cosmetologist of cadavers was 35.67% (370/1037), which was higher than those in the funeral workers in other positions, such as cremators, pick-up and administrative workers, whose ratios were 24.42% (95/389), 22.41% (52/232) and 10.40% (12/125), respectively (χ(2) were 13.682, 10.967 and 32.263, respectively; P values were all < 0.05). And the isolated ratios of pathogens and conditional pathogens in cremators and pick-up workers were significantly higher than that in administrative workers (χ(2) were 11.206 and 7.873, respectively; P values were all < 0.05). CONCLUSION: Lots of bacteria were found in the samples from hands of funeral staffs. The isolated ratio of pathogens and conditional pathogens was different between the funeral staffs in different positions; while the highest was from embalmed/cosmetologist of cadavers and the lowest was from administrators.
Assuntos
Mãos/microbiologia , Práticas Mortuárias , Exposição Ocupacional , Bactérias/isolamento & purificação , Humanos , Testes de Sensibilidade MicrobianaRESUMO
Transition metal selenides are very ideal as electroactive battery material for hybrid supercapacitors owing to their high electrochemical activity and metallic electrical conductivity, but their environmental friendly fabrication and complex structure construction is still a big challenge. Here, a simple low-temperature selenization method has been developed to green synthesize a series of Ni-Co selenide samples with a hierarchical nanoparticle/nanosheet structure. The hierarchical structure has been constructed by the recrystallization of sample during the selenization process, which can be greatly influenced by the Co composition. The specific hierarchical structure provides more electroactive sites for charge storage, and the optimized synergy between the Ni and Co compositions further greatly tunes the charge storage performance, as a result, the Ni0.67Co0.33Se2 shows the best performance with a specific capacity of 447 C g-1 at 1 A g-1, which is much higher than the Ni-Co selenides with the other Ni to Co ratios and the Ni-Co oxides. The Ni0.67Co0.33Se2 retains 97% of the specific capacity after 2000 cycles, demonstrating its excellent cycling stability. A hybrid supercapacitor has been assembled using Ni0.67Co0.33Se2 as the positive electrode, which shows both high specific energy and specific power performances.
RESUMO
OBJECTIVE: To develop and evaluate the efficiency of air purification and sterilization instrument based on nano-sized TiO(2) photocatalytic technique. METHODS: The nano-sized TiO(2) photocatalytic air purification and sterilization instrument was designed and a sample had been prepared. The sterilization efficiencies for E.coli and Klebsiella by the nano-sized TiO(2) photocatalytic instrument and ultraviolet (UV) were measured in closed labs. The on-site efficiency of the instrument was evaluated, too. RESULTS: The nano-sized TiO(2) photocatalytic air purification and sterilization instrument was composed of five units: rough filter, nano-sized TiO(2) photocatalytic unit, activated carbon fiber filter, negative ion generator, and programmed control unit. The E.coli killing rates by the nano-sized TiO(2) photocatalytic instrument were 76.0%, 81.8%, 77.5%, and 80.7% at 30, 60, 90, and 120 minutes, respectively. There was no significant difference between the E.coli killing rates of the instrument and UV (P > 0.05), except the 120 minutes timepoint. The Klebsiella killing rates by the instrument were 78.4%, 79.5%, 67.3%, and 58.5% at 30, 60, 90, and 120 minutes, respectively. The Klebsiella killing efficiencies of the instrument at 30 and 60 minutes were better than that of UV (P < 0.01). There was no significant difference between the Klebsiella killing efficiencies of the instrument and UV (P > 0.05). CONCLUSION: The air sterilization efficiency of the nano-sized TiO(2) photocatalytic instrument should be equivalent or better as compared with the UV. This instrument might be used for the air purification and sterilization of the public locations.