采用900 e V能量的电子对直玻璃管进行了穿透实验,测量了玻璃管在倾角为–0.15°,–0.4°和–1.15°时充电过程角分布的时间演化,以及平衡态下出射电子能谱.发现穿透率随时间先下降后上升最后趋于平稳,下降的时间随倾角的...采用900 e V能量的电子对直玻璃管进行了穿透实验,测量了玻璃管在倾角为–0.15°,–0.4°和–1.15°时充电过程角分布的时间演化,以及平衡态下出射电子能谱.发现穿透率随时间先下降后上升最后趋于平稳,下降的时间随倾角的增大而减小.当倾角为–0.4°和–1.15°时,电子穿透率下降到最低点时几乎看不到穿透电子(穿透率小于3‰),这种穿透率最低点状态保持时间随倾角增大而增大.穿透电子的角分布中心随着时间变化.在平稳状态时,发现穿透电子的能量损失随倾角增大而增大.采用蒙特卡罗方法模拟了电子经过管壁不同次数反射后的能谱,与测量能谱进行对比,发现–0.15°,–0.4°和–1.15°倾角下,穿透电子分别经历了管壁的一次、两次和三次与表面的反射过程.基于此,本文对电子穿越玻璃管的充电过程动力学给出了物理解释.实验结果和理论分析表明,在小倾角下玻璃管内能形成宏观负电荷累积,排斥后续电子形成反射,增加电子出射概率,这对应用绝缘体微结构,例如玻璃锥管产生稳定的电子微束具有重要的参考意义.展开更多
目的:探究骨桥蛋白(OPN)基因单核苷酸多态性(rs1126772、rs117291487、rs11730582、rs142608941、rs6813526)与男性弱精子症的关系。方法:选取135例弱精子症不育男性为病例组,239例有生育史的健康男性作为对照组,运用多重单碱基延伸PCR...目的:探究骨桥蛋白(OPN)基因单核苷酸多态性(rs1126772、rs117291487、rs11730582、rs142608941、rs6813526)与男性弱精子症的关系。方法:选取135例弱精子症不育男性为病例组,239例有生育史的健康男性作为对照组,运用多重单碱基延伸PCR技术(SNaPshot)对OPN基因rs1126772、rs117291487、rs11730582、rs142608941、rs6813526位点进行基因分型检测,分析这5个位点多态性与男性弱精子症的相关性。结果:OPN基因rs1126772位点GA基因型和A等位基因与弱精子症发病风险存在相关性(GA vs AA:OR=0.55,95%CI,0.35~0.86,P=0.009;A vs G:OR=0.64,95%CI,0.46~0.89,P=0.007);rs11730582位点CT基因型和T等位基因与弱精子症发病风险相关(CT vs TT:OR=0.526,95%CI,0.34~0.82,P=0.009;T vs C:OR=0.60,95%CI,0.44-0.83,P=0.002),单倍型分析发现,AATCT单倍型可能具有降低弱精子症的发病风险(AATCT:OR=0.61,95%CI,0.42~0.88,P=0.008)。结论:OPN基因rs1126772和rs11730582位点多态性可能与降低弱精子症的发生相关。展开更多
[Objective]The aim was to study the interannual changes of atmospheric dust deposition and quantity of combustible dust-fall in Chaihe basin.[Method]Taking Chaihe Basin in south Dianchi as study area,the atmospheric d...[Objective]The aim was to study the interannual changes of atmospheric dust deposition and quantity of combustible dust-fall in Chaihe basin.[Method]Taking Chaihe Basin in south Dianchi as study area,the atmospheric dust deposition and combustible substances in the residential,chemical area,sand production area and watershed in Chaihe basin were measured.The pollution and interannual changes of atmospheric dust in Chaihe basin were discussed.[Result]In the residential,chemical area,sand production area and watershed,the amount of sand was the highest in sand production area and lowest in the watershed.While the dust amount in the chemical area and watershed areas were lower than sand production area and higher than watershed area.In the four chosen areas,the highest value of dust appeared in autumn and the lowest value appeared in precipitation season.Sand in other months changed and the change scale was large,which indicated that the meteorological condition had large influences on dust.Relevance analysis indicated that the dust in sand production area showed positive relevance to flammable amount of dust.Dust and flammable amount had positive relevance.[Conclusion]The study provided theoretical basis for the atmospheric pollution situation in Chaihe Basin.展开更多
文摘采用900 e V能量的电子对直玻璃管进行了穿透实验,测量了玻璃管在倾角为–0.15°,–0.4°和–1.15°时充电过程角分布的时间演化,以及平衡态下出射电子能谱.发现穿透率随时间先下降后上升最后趋于平稳,下降的时间随倾角的增大而减小.当倾角为–0.4°和–1.15°时,电子穿透率下降到最低点时几乎看不到穿透电子(穿透率小于3‰),这种穿透率最低点状态保持时间随倾角增大而增大.穿透电子的角分布中心随着时间变化.在平稳状态时,发现穿透电子的能量损失随倾角增大而增大.采用蒙特卡罗方法模拟了电子经过管壁不同次数反射后的能谱,与测量能谱进行对比,发现–0.15°,–0.4°和–1.15°倾角下,穿透电子分别经历了管壁的一次、两次和三次与表面的反射过程.基于此,本文对电子穿越玻璃管的充电过程动力学给出了物理解释.实验结果和理论分析表明,在小倾角下玻璃管内能形成宏观负电荷累积,排斥后续电子形成反射,增加电子出射概率,这对应用绝缘体微结构,例如玻璃锥管产生稳定的电子微束具有重要的参考意义.
文摘目的:探究骨桥蛋白(OPN)基因单核苷酸多态性(rs1126772、rs117291487、rs11730582、rs142608941、rs6813526)与男性弱精子症的关系。方法:选取135例弱精子症不育男性为病例组,239例有生育史的健康男性作为对照组,运用多重单碱基延伸PCR技术(SNaPshot)对OPN基因rs1126772、rs117291487、rs11730582、rs142608941、rs6813526位点进行基因分型检测,分析这5个位点多态性与男性弱精子症的相关性。结果:OPN基因rs1126772位点GA基因型和A等位基因与弱精子症发病风险存在相关性(GA vs AA:OR=0.55,95%CI,0.35~0.86,P=0.009;A vs G:OR=0.64,95%CI,0.46~0.89,P=0.007);rs11730582位点CT基因型和T等位基因与弱精子症发病风险相关(CT vs TT:OR=0.526,95%CI,0.34~0.82,P=0.009;T vs C:OR=0.60,95%CI,0.44-0.83,P=0.002),单倍型分析发现,AATCT单倍型可能具有降低弱精子症的发病风险(AATCT:OR=0.61,95%CI,0.42~0.88,P=0.008)。结论:OPN基因rs1126772和rs11730582位点多态性可能与降低弱精子症的发生相关。
文摘[Objective]The aim was to study the interannual changes of atmospheric dust deposition and quantity of combustible dust-fall in Chaihe basin.[Method]Taking Chaihe Basin in south Dianchi as study area,the atmospheric dust deposition and combustible substances in the residential,chemical area,sand production area and watershed in Chaihe basin were measured.The pollution and interannual changes of atmospheric dust in Chaihe basin were discussed.[Result]In the residential,chemical area,sand production area and watershed,the amount of sand was the highest in sand production area and lowest in the watershed.While the dust amount in the chemical area and watershed areas were lower than sand production area and higher than watershed area.In the four chosen areas,the highest value of dust appeared in autumn and the lowest value appeared in precipitation season.Sand in other months changed and the change scale was large,which indicated that the meteorological condition had large influences on dust.Relevance analysis indicated that the dust in sand production area showed positive relevance to flammable amount of dust.Dust and flammable amount had positive relevance.[Conclusion]The study provided theoretical basis for the atmospheric pollution situation in Chaihe Basin.
