Studies on PVA-CMC-KOH-H_2O Alkaline Polymer Electrolytes

由聚乙烯醇(PVA)与羧甲基纤维素钠(CMC)制备PVA-CMC-KOH-H2O碱性聚合物电解质膜,应用交流阻抗、循环伏安、差热分析和红外光谱等实验方法表征、研究其性能.结果表明,该碱性聚合物电解质的室温电导率可达到10-2S.cm-1数量级,在不锈钢惰性电极上的电化学稳定窗口约为1.6 V.另外,还研究了聚合物电解质膜中KOH、H2O和CMC对体系电导率的影响以及PVA-CMC-KOH-H2O碱性聚合物电解质在N i/MH电池中的初步应用.初步结果表明,由PVA-CMC-KOH-H2O聚合物电解质组装的N i/MH电池,其低倍率放电性能较好.A given amount of sodium carboxymethyl cellulose(CMC)was added to PVA complex and thus the PVA-CMC-KOH-H_(2)O alkaline polymer electrolyte with this modification was prepared.The properties of the polymer electrolyte films were characterized by AC impedance,cyclic voltammetry,differential thermal analysis and infrared spectroscopic analysis methods.The polymer electrolyte exhibited a high ionic conductivity,typically 10~(-2)S·cm~(-1) with an electrochemical stability window of about 1.6 V on stainless steel blocking electrodes.The influence of the film composition such as KOH,H_(2)O and CMC on ion conductivity was investigated.In addition,a preliminary study was carried out on the polymer electrolyte for Ni/MH battery.It was shown that the Ni/MH battery with the polymer electrolyte presented a good charge/discharge performance at lower discharge rates.作者联系地址：上海大学理学院化学系,上海大学理学院化学系 上海200444,上海200444Author's Address: *,ZHAO JunDepartment of Chemistry,College of Sciences,Shanghai University,Shanghai 200444,Chin

135MeV／u~（12）C和铁相互作用中靶余核的质量分布

用核化学技术测定了１３５ＭｅＶ／ｕ１２Ｃ和铁相互作用中的靶余核的生成截面，通过高斯电荷分布函数得到了靶余核的质量分布．与４６ＭｅＶ／ｕ１２Ｃ＋Ｃｕ相比，发现Ａ＜３０质量区的产额明显增加，且产物有偏向丰中子一侧的趋势．实验测定的质量分布与熔合碎裂模型和级联两体模型的计算结果进行了比较，结果似乎表明在很高入射能情况下多重碎裂衰变是Ａ＜３０靶余核生成的主要反应机制．The formation cross sections of target residues have been measured from the interaction of iron with 135MeV/u12C ions.With the help of assumption of Gaussian charge distribution,the mass yield distribution was obtained.We found that the yield in mass region of A<30 were notably increased and the products got away to neutron-excessive.The experimental results were compared with calculations based on the statistical fusion fragmentation model and on the sequential binary decay model,respectively. It seems国家自然科学基

“西油东送”工程甘肃段水土流失防治研究/Soil and Water Loss Control Along Gansu Pipeline in West to East Petroleum Transportation Project[J]

中国石油西部成品油管道是目前国内运输距离最长的输油管道之一。管道铺设过程中,大量采用机械施工,路堑开挖,路堤填筑,取土采石和架桥砌涵等,破坏了公路沿线原生地貌及植被,扰动了表土结构,致使土体抗蚀能力降低。在总结工程区自然情况基础上,分析了＂西油东送＂工程甘肃段的水土流失问题和其对生态环境的影响。结果认为管道工程防护类型必须坚持＂三同时＂原则,并应该采取如下防治方针：（1）综合治理与综合开发相结合;（2）科学配置防治措施;（3）防止新的水土流失发生

JUNO Sensitivity on Proton Decay p→νˉK+p\to \bar\nu K^+ Searches

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this paper, the potential on searching for proton decay in $p\to \bar\nu K^+$ mode with JUNO is investigated.The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits to suppress the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar\nu K^+$ is 36.9% with a background level of 0.2 events after 10 years of data taking. The estimated sensitivity based on 200 kton-years exposure is $9.6 \times 10^{33}$ years, competitive with the current best limits on the proton lifetime in this channel

JUNO sensitivity on proton decay p → ν K + searches*

The Jiangmen Underground Neutrino Observatory (JUNO) is a large liquid scintillator detector designed to explore many topics in fundamental physics. In this study, the potential of searching for proton decay in the $p\to \bar{\nu} K^+$ mode with JUNO is investigated. The kaon and its decay particles feature a clear three-fold coincidence signature that results in a high efficiency for identification. Moreover, the excellent energy resolution of JUNO permits suppression of the sizable background caused by other delayed signals. Based on these advantages, the detection efficiency for the proton decay via $p\to \bar{\nu} K^+$ is 36.9% ± 4.9% with a background level of $0.2\pm 0.05({\rm syst})\pm$$0.2({\rm stat})$ events after 10 years of data collection. The estimated sensitivity based on 200 kton-years of exposure is $9.6 \times 10^{33}$ years, which is competitive with the current best limits on the proton lifetime in this channel and complements the use of different detection technologies