Biological CO2 sequestration by microalgae is a promising and environmentally friendly technology applied to sequester CO2. The characteristics of neutral lipid accumulation by two marine oil-rich microalgal strains,n...Biological CO2 sequestration by microalgae is a promising and environmentally friendly technology applied to sequester CO2. The characteristics of neutral lipid accumulation by two marine oil-rich microalgal strains,namely, Isochrysis galbana and Nannochloropsis sp., through CO2 enrichment cultivation were investigated in this study. The optimum culture conditions of the two microalgal strains are 10% CO2 and f medium. The maximum biomass productivity, total lipid content, maximum lipid productivity, carbon content, and CO2 fixation ability of the two microalgal strains were obtained. The corresponding parameters of the two strains were as follows：（（142.42±4.58） g/（m^2·d）,（149.92±1.80） g/（m^2·d））,（（39.95±0.77）%,（37.91±0.58）%）,（（84.47±1.56） g/（m^2·d）,（89.90±1.98） g/（m^2·d））,（（45.98±1.75）%,（46.88±2.01）%）, and（（33.74±1.65） g/（m^2·d）,（34.08±1.32） g/（m^2·d））. Results indicated that the two marine microalgal strains with high CO2 fixation ability are potential strains for marine biodiesel development coupled with CO2 emission reduction.展开更多
对滇中城市群绿色空间生态系统服务价值(Ecosystem Service value, ESV)进行时空演变及驱动因素的探析,有利于了解区域生态系统服务空间差异,有助于规划者从宏观层面掌握滇中城市群的自然资源情况,合理地制定规划建设策略。研究以滇中...对滇中城市群绿色空间生态系统服务价值(Ecosystem Service value, ESV)进行时空演变及驱动因素的探析,有利于了解区域生态系统服务空间差异,有助于规划者从宏观层面掌握滇中城市群的自然资源情况,合理地制定规划建设策略。研究以滇中城市群49个区、县、市作为研究单元,对2000年、2010年、2019年3期的ESV进行量化,并收集“自然—社会—经济”维度的驱动因子,采用主成分分析与地理加权回归探讨“自然—社会—经济”因素对滇中城市群绿色空间ESV的驱动作用。结果表明:(1) 2000—2019年滇中城市群绿色空间的ESV总体呈现增加状态,一级服务类型中,供给、支持和文化服务小幅度上升,调节服务小幅度下降,二级服务类型中,气候与水文调节对生态系统服务功能的贡献最大,其次为土壤保持、生物多样性和气体调节;(2) 3期ESV空间分布特征较为一致,呈现城市群边缘地区的ESV高于城市群中部地区的ESV的特征;(3)社会因素对滇中城市群绿色空间的ESV的时空演变影响最大、其次为自然因素和经济因素,主要驱动因子为城镇化率、人均GDP、人口密度、森林覆盖率、第二产业占比。(4)城镇化率、人口密度及第二产业占比呈现两极化驱动特征;人均GDP呈现负向驱动特征;森林覆盖率呈现正向驱动特征。综上,近20年滇中城市群绿色空间的ESV增加,其变化主要受社会因素影响。研究可为滇中城市群的可持续发展提供参考。展开更多
Microplastics(<5 mm)are ubiquitous in the environment and can pose potential danger to the ecosystem and even human health.As the sink of microplastics,the ocean,especially the densely populated coastal area,has be...Microplastics(<5 mm)are ubiquitous in the environment and can pose potential danger to the ecosystem and even human health.As the sink of microplastics,the ocean,especially the densely populated coastal area,has become a hotspot for research on microplastic pollution.In the last decade,the research of marine microplastics has been rapidly increasing in China.This review summarized the microplastic research conducted in China marine waters so far,and introduced the trends and progress of microplastic research in the four seas along the coast of China.We reviewed and compared the current sampling,extraction,and identification methodologies of China's microplastic research.According to the sampling method,the 30 reviewed studies were separated into two categories,trawl sampling and bulk sampling,to summarize relevant data,including abundance,sizes,shapes,colors and polymer types of microplastics.The main results showed that the distribution of microplastics in China's marine environment varied significantly,with offshore mariculture zones and the South China Sea being the most contaminated areas.Transparent,granules(or pellets)and fibers were the most dominant microplastic colors and shapes,and the size of microplastics was influenced significantly by the sampling method.Polyethylene(PE),polypropylene(PP)and polystyrene(PS)were the most common polymer types found in the China Sea,accounting for 49.96%,29.97%,and 12.38%of the total studies,respectively.Compared with other global data,China's coastal microplastic pollution is at an intermediate level and does not seem to be a major microplastic pollution source.展开更多
Hydrogen combustion in a nuclear power plant may threaten the integrity of some important systems and components.In this paper,the effect of hydrogen combustion in the primary pump compartment is analyzed by different...Hydrogen combustion in a nuclear power plant may threaten the integrity of some important systems and components.In this paper,the effect of hydrogen combustion in the primary pump compartment is analyzed by different initial hydrogen concentration and igniter locations using Computational Fluid Dynamics method.The results show that the combustion is confined to a limited area without pump damage at about 6.6%hydrogen volume fraction.Once igniting the hydrogen,the combustion affects the whole compartment at the 12%hydrogen volume fraction.The stress caused by the great temperature gradient or high temperature may damage the primary pump. Igniters at the lower location accelerate the combustion process and cause a threat to the pump integrity.展开更多
基金The Basic Scientific Fund for National Public Research Institutes of China under contract Nos 2017Q09 and2016Q02the National Natural Science Foundation of China under contract No.41776176+2 种基金the National Key Research and Development Program of China under contract No.2017YFC1404604the Shandong Provincial Natural Science Foundation under contract No.ZR2015PD003the 2012 Taishan Scholar
文摘Biological CO2 sequestration by microalgae is a promising and environmentally friendly technology applied to sequester CO2. The characteristics of neutral lipid accumulation by two marine oil-rich microalgal strains,namely, Isochrysis galbana and Nannochloropsis sp., through CO2 enrichment cultivation were investigated in this study. The optimum culture conditions of the two microalgal strains are 10% CO2 and f medium. The maximum biomass productivity, total lipid content, maximum lipid productivity, carbon content, and CO2 fixation ability of the two microalgal strains were obtained. The corresponding parameters of the two strains were as follows：（（142.42±4.58） g/（m^2·d）,（149.92±1.80） g/（m^2·d））,（（39.95±0.77）%,（37.91±0.58）%）,（（84.47±1.56） g/（m^2·d）,（89.90±1.98） g/（m^2·d））,（（45.98±1.75）%,（46.88±2.01）%）, and（（33.74±1.65） g/（m^2·d）,（34.08±1.32） g/（m^2·d））. Results indicated that the two marine microalgal strains with high CO2 fixation ability are potential strains for marine biodiesel development coupled with CO2 emission reduction.
基金the National Natural Science Foundation of China(No.42176239)the Asian Countries Maritime Cooperation Fund(No.99950410)the Investigation and Evaluation of Microplastics in Seawater(No.ZY0722044)。
文摘Microplastics(<5 mm)are ubiquitous in the environment and can pose potential danger to the ecosystem and even human health.As the sink of microplastics,the ocean,especially the densely populated coastal area,has become a hotspot for research on microplastic pollution.In the last decade,the research of marine microplastics has been rapidly increasing in China.This review summarized the microplastic research conducted in China marine waters so far,and introduced the trends and progress of microplastic research in the four seas along the coast of China.We reviewed and compared the current sampling,extraction,and identification methodologies of China's microplastic research.According to the sampling method,the 30 reviewed studies were separated into two categories,trawl sampling and bulk sampling,to summarize relevant data,including abundance,sizes,shapes,colors and polymer types of microplastics.The main results showed that the distribution of microplastics in China's marine environment varied significantly,with offshore mariculture zones and the South China Sea being the most contaminated areas.Transparent,granules(or pellets)and fibers were the most dominant microplastic colors and shapes,and the size of microplastics was influenced significantly by the sampling method.Polyethylene(PE),polypropylene(PP)and polystyrene(PS)were the most common polymer types found in the China Sea,accounting for 49.96%,29.97%,and 12.38%of the total studies,respectively.Compared with other global data,China's coastal microplastic pollution is at an intermediate level and does not seem to be a major microplastic pollution source.
基金Supported by National Basic Research Program of China(No.2009CB724301)National Natural Science Foundation of China(No.11075104)
文摘Hydrogen combustion in a nuclear power plant may threaten the integrity of some important systems and components.In this paper,the effect of hydrogen combustion in the primary pump compartment is analyzed by different initial hydrogen concentration and igniter locations using Computational Fluid Dynamics method.The results show that the combustion is confined to a limited area without pump damage at about 6.6%hydrogen volume fraction.Once igniting the hydrogen,the combustion affects the whole compartment at the 12%hydrogen volume fraction.The stress caused by the great temperature gradient or high temperature may damage the primary pump. Igniters at the lower location accelerate the combustion process and cause a threat to the pump integrity.
