It is shown by the result of the dual-cultured experiment that the inhibitory rate of DZW-47 was 60.42%, and the inhibitory rates of R.solani by actinomyces ZLR-2 and ZLR-11 were 43.75% and 43.05%, lower than that of ...It is shown by the result of the dual-cultured experiment that the inhibitory rate of DZW-47 was 60.42%, and the inhibitory rates of R.solani by actinomyces ZLR-2 and ZLR-11 were 43.75% and 43.05%, lower than that of DZW-47. The inhibitory mycelia growth mechanism of different strains on R.solani was quite different, with DZW-3 mainly on the aspect of hyperparasitism, DZW-21 on the synergism of hyperparasitism and metabolite, DZW-47 on the synergism of nutrient competition and secondary metabolite, ZLR-2 and ZLR-11 on producing secondary metabolite. Controlling efficiency of seedling bed accorded basically with that of the broth. The controlling efficiency of DZW-47, ZLR-2, ZLR-11, DZW-21 and DZW-3 were 97.20%, 95.7%, 94.6%, 93.6% and 89.20%, respectively.展开更多
Clay minerals are ubiquitous on epigeosphere, especially in soils and sediments where microbes thrive. The clay-microbe interactions are common in these geological media and greatly contribute to accelerating the mine...Clay minerals are ubiquitous on epigeosphere, especially in soils and sediments where microbes thrive. The clay-microbe interactions are common in these geological media and greatly contribute to accelerating the mineral transformation process, e.g. the illitization of nontronite (a Fe-rich smectite) catalyzed by microbes under anoxic atmosphere in 2 weeks. However, few has considered montmorillonite, a Fe-poor smectite more typical in natural environments than nontronite. This study therefore focuses on the interaction between montmorillonite and bacteria under conditions relevant to those in natural soils and sediments.展开更多
Because of its broad spectrum and high efficiency,the microwave disinfection was used to control the airborne microbial contaminates in VAC system.Some microwave disinfection devices were developed combined with air f...Because of its broad spectrum and high efficiency,the microwave disinfection was used to control the airborne microbial contaminates in VAC system.Some microwave disinfection devices were developed combined with air filter,the design and calculation method was presented,and the disinfection effects on White staphylococcus,Staphylococcus aureus,Bacillus Subtilis,Escherichi coli were measured.The results show that the major influence factors on disinfection effect are microwave power,water-content of filter material,disinfecting duration.After 15 min,the kill ratio is >90%,and the log value is >1.The microwave field is uniform and the kill effect of bacteria on each surface of filter is the same,without statistically significant difference.展开更多
In order to investigate the bacteria and fungi aerosol characteristic distribution in HVAC-system and its components at Shaanxi History Museum.Measurements were performed to probe the bacteria and fungi aerosol in HVA...In order to investigate the bacteria and fungi aerosol characteristic distribution in HVAC-system and its components at Shaanxi History Museum.Measurements were performed to probe the bacteria and fungi aerosol in HVAC systems,located at Xi'an city,China.The results showed that there was fungi growth inside the ventilation ducts,fungi contamination was worse than bacteria,and both of them were distributed into occupied space with the air supply ducts.The dominating genera of fungi was found to be Penicillium spp.and Aspergillus spp.,which was respectively 46.1% and 20.7% in settling fungi,and the dominating genera of fungi in dust were Cladosporium spp.and Penicillium spp.,which was 41.8% and 30.1% respectively.It suggests that available measures to improve and control the performance of HVAC-systems such as the maintenance,management and cleaning should be taken to prevent this pollution and to develop strategies to keep this pollution away.展开更多
The Earth surface is a multiple open system. Semiconducting minerals, including most metal oxides and sulfides, absorb visible light of the solar spectrum. Microorganisms evolve varied pathways to get carbon and energ...The Earth surface is a multiple open system. Semiconducting minerals, including most metal oxides and sulfides, absorb visible light of the solar spectrum. Microorganisms evolve varied pathways to get carbon and energy sources. It is obvious that the interaction among solar light, semiconducting minerals, photoelectron/photohole, organics, inorganics, valence electrons and microorganisms occurs continuously on our planet. In a recent study, Lu et al. (2012) presented evidence demonstrating solar energy mediated by semiconducting mineral photocatalysis, acting as energy source, promoted the growth of some non-photosynthetic bacteria and revealed that the ternary system of microorganisms, minerals and solar light has played a critical role in the history of life on our planet. In simulated system, under simulated solar light semiconducting minerals, such as metal oxides and metal sulfides, generates photoelectrons which could be used by non-phototrophic microorganisms to support their metabolisms. The growth of microorganism was closely related to photon quantity and energy, and the microorganism growth and mineral light absorption spectra were fitted well under different light wavelengths. The overall energy efficiency from photon to biomass was 0.13‰ to 1.9‰. Further studies revealed that in natural soil systems, semiconducting mineral photocatalysis could influence the microbial population. Solar energy utilization pathway by nonphototrophic microorganisms mediated by semiconducting mineral photocatalysis provides a new concept to evaluate the origin and evolution of life. Semiconducting minerals are ubiquitous on Earth’s surface and widely participate in redox reactions following photoelectron-photohole pairs excited by solar light. As photoholes can be easily scavenged by environmental reductive substances and microorganisms possess multiple strategies to utilize extracellular electrons, the highly reductive photoelectrons serve as potential energy source for microbial life. The discovery of this pathway extends our knowledge on the use of solar energy by nonphototrophic microorganisms, and provides important clues to evaluate life on the early Earth. Microorganisms, minerals and solar light constitute a complex but important ternary system through Earth history. The discovery of the novel energy conversion pathway in this system demonstrates how nonphototrophic microorganisms directly or indirectly utilized photoelectrons as the solar energy source. The fully comprehending of nonphototrophic bacteria solar energy utilization conducted by semiconducting minerals in present environment will greatly help us to better understand the energy transform mechanism among interfaces of lithosphere, pedosphere, hydrosphere and biosphere.展开更多
基金Supported by Technological Department Momentous Item of Heilongjiang Province(GA06C101-07)
文摘It is shown by the result of the dual-cultured experiment that the inhibitory rate of DZW-47 was 60.42%, and the inhibitory rates of R.solani by actinomyces ZLR-2 and ZLR-11 were 43.75% and 43.05%, lower than that of DZW-47. The inhibitory mycelia growth mechanism of different strains on R.solani was quite different, with DZW-3 mainly on the aspect of hyperparasitism, DZW-21 on the synergism of hyperparasitism and metabolite, DZW-47 on the synergism of nutrient competition and secondary metabolite, ZLR-2 and ZLR-11 on producing secondary metabolite. Controlling efficiency of seedling bed accorded basically with that of the broth. The controlling efficiency of DZW-47, ZLR-2, ZLR-11, DZW-21 and DZW-3 were 97.20%, 95.7%, 94.6%, 93.6% and 89.20%, respectively.
文摘Clay minerals are ubiquitous on epigeosphere, especially in soils and sediments where microbes thrive. The clay-microbe interactions are common in these geological media and greatly contribute to accelerating the mineral transformation process, e.g. the illitization of nontronite (a Fe-rich smectite) catalyzed by microbes under anoxic atmosphere in 2 weeks. However, few has considered montmorillonite, a Fe-poor smectite more typical in natural environments than nontronite. This study therefore focuses on the interaction between montmorillonite and bacteria under conditions relevant to those in natural soils and sediments.
基金Supported by China Postdoctoral Science Foundation and Municipal and Environmental Engineering Research Province Key Laboratory Foundation,Shenyang Jianzhu University
文摘Because of its broad spectrum and high efficiency,the microwave disinfection was used to control the airborne microbial contaminates in VAC system.Some microwave disinfection devices were developed combined with air filter,the design and calculation method was presented,and the disinfection effects on White staphylococcus,Staphylococcus aureus,Bacillus Subtilis,Escherichi coli were measured.The results show that the major influence factors on disinfection effect are microwave power,water-content of filter material,disinfecting duration.After 15 min,the kill ratio is >90%,and the log value is >1.The microwave field is uniform and the kill effect of bacteria on each surface of filter is the same,without statistically significant difference.
基金Supported by the National Natural Science Foundation of China(50878177)the Rearch Fund for the Doctoral Program of Higher Education
文摘In order to investigate the bacteria and fungi aerosol characteristic distribution in HVAC-system and its components at Shaanxi History Museum.Measurements were performed to probe the bacteria and fungi aerosol in HVAC systems,located at Xi'an city,China.The results showed that there was fungi growth inside the ventilation ducts,fungi contamination was worse than bacteria,and both of them were distributed into occupied space with the air supply ducts.The dominating genera of fungi was found to be Penicillium spp.and Aspergillus spp.,which was respectively 46.1% and 20.7% in settling fungi,and the dominating genera of fungi in dust were Cladosporium spp.and Penicillium spp.,which was 41.8% and 30.1% respectively.It suggests that available measures to improve and control the performance of HVAC-systems such as the maintenance,management and cleaning should be taken to prevent this pollution and to develop strategies to keep this pollution away.
文摘The Earth surface is a multiple open system. Semiconducting minerals, including most metal oxides and sulfides, absorb visible light of the solar spectrum. Microorganisms evolve varied pathways to get carbon and energy sources. It is obvious that the interaction among solar light, semiconducting minerals, photoelectron/photohole, organics, inorganics, valence electrons and microorganisms occurs continuously on our planet. In a recent study, Lu et al. (2012) presented evidence demonstrating solar energy mediated by semiconducting mineral photocatalysis, acting as energy source, promoted the growth of some non-photosynthetic bacteria and revealed that the ternary system of microorganisms, minerals and solar light has played a critical role in the history of life on our planet. In simulated system, under simulated solar light semiconducting minerals, such as metal oxides and metal sulfides, generates photoelectrons which could be used by non-phototrophic microorganisms to support their metabolisms. The growth of microorganism was closely related to photon quantity and energy, and the microorganism growth and mineral light absorption spectra were fitted well under different light wavelengths. The overall energy efficiency from photon to biomass was 0.13‰ to 1.9‰. Further studies revealed that in natural soil systems, semiconducting mineral photocatalysis could influence the microbial population. Solar energy utilization pathway by nonphototrophic microorganisms mediated by semiconducting mineral photocatalysis provides a new concept to evaluate the origin and evolution of life. Semiconducting minerals are ubiquitous on Earth’s surface and widely participate in redox reactions following photoelectron-photohole pairs excited by solar light. As photoholes can be easily scavenged by environmental reductive substances and microorganisms possess multiple strategies to utilize extracellular electrons, the highly reductive photoelectrons serve as potential energy source for microbial life. The discovery of this pathway extends our knowledge on the use of solar energy by nonphototrophic microorganisms, and provides important clues to evaluate life on the early Earth. Microorganisms, minerals and solar light constitute a complex but important ternary system through Earth history. The discovery of the novel energy conversion pathway in this system demonstrates how nonphototrophic microorganisms directly or indirectly utilized photoelectrons as the solar energy source. The fully comprehending of nonphototrophic bacteria solar energy utilization conducted by semiconducting minerals in present environment will greatly help us to better understand the energy transform mechanism among interfaces of lithosphere, pedosphere, hydrosphere and biosphere.
