通过高能电子束辐照（higll-energy electron beam，EB）法研究了氧气浓度对2，4-D降解的影响，结果表明：与饱和空气条件下对比，辐照过程中充入氧气明显提高2，4-D的降解效率，在饱和氧气和4kGy的辐照剂量条件下，2，4-D去除率达到92...通过高能电子束辐照（higll-energy electron beam，EB）法研究了氧气浓度对2，4-D降解的影响，结果表明：与饱和空气条件下对比，辐照过程中充入氧气明显提高2，4-D的降解效率，在饱和氧气和4kGy的辐照剂量条件下，2，4-D去除率达到92．5％，Cl-释放量为30．0～35．4mg／L，TOC去除率为22．9％．辐照过程中溶液的pH值与辐照剂量和氧气浓度关系不明显，均由9降为4左右．展开更多
By using a two-dimensional particle-in-cell simulation,we demonstrate a scheme for highenergy-density electron beam generation by irradiating an ultra intense laser pulse onto an aluminum（Al） target.With the laser h...By using a two-dimensional particle-in-cell simulation,we demonstrate a scheme for highenergy-density electron beam generation by irradiating an ultra intense laser pulse onto an aluminum（Al） target.With the laser having a peak intensity of 4×10^23W cm^-2,a high quality electron beam with a maximum density of 117 nc and a kinetic energy density up to8.79×10^18J m^-3 is generated.The temperature of the electron beam can be 416 Me V,and the beam divergence is only 7.25°.As the laser peak intensity increases（e.g.,1024 W cm^-2）,both the beam energy density（3.56×10^19J m^-3） and the temperature（545 Me V） are increased,and the beam collimation is well controlled.The maximum density of the electron beam can even reach 180 nc.Such beams should have potential applications in the areas of antiparticle generation,laboratory astrophysics,etc.展开更多
To study the molecular mechanism of high mutation frequency induced by high-energy-pulse-electron (HEPE) beam radiation, the effects of HEPE radiation on yeast cells, plasma membrane, plasmid DNA, and protein activity...To study the molecular mechanism of high mutation frequency induced by high-energy-pulse-electron (HEPE) beam radiation, the effects of HEPE radiation on yeast cells, plasma membrane, plasmid DNA, and protein activity were investigated by means of cell counting, gel electrophoresis, AO/EB double fluorescent staining, etc. The results showed that the viability of yeast cells declined statistically with increase of absorbed doses. The half lethal dose (LD50) was 134 Gy. HEPE beam radiation had little influence on the function of plasma membrane and protein, while it could induce much DNA damage of single strand breaks (SSB) and double strand breaks (DSB) that were required for gene mutation. The G-value for DSB formation of HEPE beam radiation in aqueous solution was 5.7 times higher than that caused by 60Co gamma rays. HEPE can be a new effective method for induced mutation breeding and deserves further research in the future.展开更多
文摘通过高能电子束辐照（higll-energy electron beam，EB）法研究了氧气浓度对2，4-D降解的影响，结果表明：与饱和空气条件下对比，辐照过程中充入氧气明显提高2，4-D的降解效率，在饱和氧气和4kGy的辐照剂量条件下，2，4-D去除率达到92．5％，Cl-释放量为30．0～35．4mg／L，TOC去除率为22．9％．辐照过程中溶液的pH值与辐照剂量和氧气浓度关系不明显，均由9降为4左右．
基金financially supported by the National Natural Science Foundation of China(Nos.11475260,11305264,11622547,91230205,and 11474360)the National Basic Research Program of China(No.2013CBA01504)the Research Project of NUDT(No.JC14-02-02)
文摘By using a two-dimensional particle-in-cell simulation,we demonstrate a scheme for highenergy-density electron beam generation by irradiating an ultra intense laser pulse onto an aluminum（Al） target.With the laser having a peak intensity of 4×10^23W cm^-2,a high quality electron beam with a maximum density of 117 nc and a kinetic energy density up to8.79×10^18J m^-3 is generated.The temperature of the electron beam can be 416 Me V,and the beam divergence is only 7.25°.As the laser peak intensity increases（e.g.,1024 W cm^-2）,both the beam energy density（3.56×10^19J m^-3） and the temperature（545 Me V） are increased,and the beam collimation is well controlled.The maximum density of the electron beam can even reach 180 nc.Such beams should have potential applications in the areas of antiparticle generation,laboratory astrophysics,etc.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 30570376 and 50673078)the Shanghai Key Fundamental Project (Grant No. 06JC14068)the Innovation Program of Shanghai Municipal Education Commis-sion (Grant No. 08ZZ21)
文摘To study the molecular mechanism of high mutation frequency induced by high-energy-pulse-electron (HEPE) beam radiation, the effects of HEPE radiation on yeast cells, plasma membrane, plasmid DNA, and protein activity were investigated by means of cell counting, gel electrophoresis, AO/EB double fluorescent staining, etc. The results showed that the viability of yeast cells declined statistically with increase of absorbed doses. The half lethal dose (LD50) was 134 Gy. HEPE beam radiation had little influence on the function of plasma membrane and protein, while it could induce much DNA damage of single strand breaks (SSB) and double strand breaks (DSB) that were required for gene mutation. The G-value for DSB formation of HEPE beam radiation in aqueous solution was 5.7 times higher than that caused by 60Co gamma rays. HEPE can be a new effective method for induced mutation breeding and deserves further research in the future.
