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本文利用导航数据研究了共形Berwald的Kropina度量.首先利用导航数据刻画了Berwald Kropina度量.在此基础上,本文得到了Kropina度量是共形Berwald度量的一个充分必要条件.进一步,刻画了具有弱迷向旗曲率的共形Berwald Kropina度量的局部结构. 相似文献
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Nonionizing energy loss (NIEL) has been applied to a number of studies concerning displacement damage effects in materials and devices. However, most studies consider only the contribution of displacement damage effects, neglecting the contribution from phonons. In this paper, a NIEL model, which considers the contribution of phonons, has been established using the Monte Carlo code SRIM. The maximum endurable fluence for silicon detectors has been estimated using the equivalent irradiation fluence compared with experimental data for the incident particles. NIEL is proportional to the equivalent irradiation fluence that the detector has received. 相似文献
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In the fabrication of a 48 mm×48 mm silicon micro-strip nuclear radiation detector with 96 strips on each side, a perfect P-N junction cannot be formed consistently by the one-step implantation process, and thus over 50% of strips produced do not meet application requirements. However, the method of stratified implantation not only avoids the P region between the surface of wafers and the P+ region, but also overcomes the shadow effect. With the help of the stratified implantation process, a perfect functional P-N junction can be formed, and over 95% of strips meet application requirements. 相似文献
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采用高效液相色谱-电感耦合等离子体质谱(HPLC-ICP-MS)联用技术对烟草中砷的形态进行分析研究。烟草样品经超纯水提取,采用阴离子交换柱,以30 mmol/L碳酸铵水溶液作流动相,成功分离了亚砷酸(As(III))、砷酸(As(V))、一甲基砷(MMA)和二甲基砷(DMA),检出限依次为0.15,0.16,0.17,0.16 ng/mL,加标回收率在73.8%~107.6%之间,相对标准偏差(RSD)均小于8.0%(n=3)。 相似文献
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采用高温固相合成法制备了Li[Ni(1-x)/3Mn(1-x)/3Co(1-x)/3Mox]O2 (x=0, 0.005, 0.01, 0.02). 对它们进行了XRD, SEM, 循环伏安及充放电容量测试, 结果发现, 掺杂x=0.01 Mo的样品具有较高的嵌锂容量和良好的循环稳定性, 在20 mA/g放电电流密度和2.3~4.6 V的电压范围内具有211.6 mAh/g的首次放电比容量, 循环50周后放电比容量仍能达到185.9 mAh/g, 容量损失为12.1%. 相似文献
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浓碱溶液中生成高铁酸盐的玻碳电极循环伏安法表征(英文) 总被引:3,自引:1,他引:3
用玻碳电极研究了与Fe(Ⅵ)/Fe(Ⅲ)电对氧化还原有关的循环伏安曲线.所研究的体系是13mol·L-1NaOH中浓度范围分别为0.015~0.06mol·L-1的Na2FeO4和0.01~0.025mol·L-1的NaFeO2溶液。另一类研究体系是胶体石墨分别与固体K2FeO4、固体KFeO2组成的混合物,将这些混合物粘附于玻碳电极表面后在13mol·L-1KOH中进行循环伏安曲线的测定。结果证明了峰电位在0.7~1.0V的阳极电流峰与峰电位在0.15~0.2V(均相对于13mol·L-1NaOH或13mol·L-1KOH溶液中的Hg/HgO参比电极)的阴极电流峰,分别与高铁酸盐的生成与还原相对应。确定了将高铁酸盐的阳极生成电流峰与阳极析氧电流峰区别开来的条件。 相似文献
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