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Epoxy-POSS/silicone rubber nanocomposites with excellent thermal stability and radiation resistance

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Chinese Chemical Letters 2022年第7期33卷 3534-3538页

作者： Mengni Shi Yinyong Ao Lei Yu Lang Sheng Shuangxiao li Jing Peng Hongbing Chen Wei Huang jiuqiang li Maolin Zhai Beijing National Laboratory for Molecular Sciences Radio Chemistry and Radiation Chemistry Key Laboratory of Fundamental ScienceThe Key Laboratory of Polymer Chemistry and Physics of the Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Institute of Nuclear Physics and Chemistry China Academy of Engineering PhysicsMianyang 621900China

Due to the rigid Si-O-Si backbone,silicone rubber(SR)have a widespread application in extreme environment such as high temperature and high-level ***,the radiation stability of SR still does not meet the practical needs in special radiation *** we prepared epoxy POSS(e POSS)/SR nanocomposites with excellent thermal stability and radiation *** a physical crosslinking point in the SR,addition of small amount of ePOSS not only enhanced the mechanical properties of the matrix,but also improved its thermal stability greatly due to their good compatibility.e POSS/SR had higher radiation stability in air than SR owing to the inhibition of radiation oxidation by ePOSS,and the yield of main gaseous radiolysis products(CH_(4),H_(2),CO and CO_(2))of SR and ePOSS/SR nanocomposites was *** analyzing the changes of chemical structure,thermal properties and mechanical properties of the ePOSS/SR nanocomposite,combined with the characteristics of gas products afterγ-irradiation,the radiation induced crosslinking and degradation mechanism of the nanocomposites was proposed comprehensively.

关键词： POSS Silicone rubber Thermal stability Radiation resistance Radiation crosslinking and degradation mechanism

Radiation synthesis and characteristics of PTFE-g-PSSA ion exchange membrane applied in vanadium redox battery

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Nuclear Science and Techniques 2007年第1期18卷 50-54页

作者： PENG Jinfen QIU Jinyi NI Jiangfeng ZHAI Maolin XU Peng PENG Jing ZHOU Henghui li jiuqiang WEI Genshuan Beijing National Laboratory for Molecular Sciences Department of Applied Chemistry College of Chemistry ＆ Molecular Engineering Peking University Beijing 100871 China

Radiation-induced grafting of styrene onto polytetrafluoroethylene (PTFE) membranes was studied by a simultaneous irradiation *** was carded out usingγ-radiation from a ^(60)Co source at room temperature. Effects of absorbed dose,atmosphere,dose rate,and the concentration of initial monomer on the degree of grafting (DOG) were investigated and the most appropriate grafting condition was ***,sulphonation of the grafted PTFE membrane (PTFE-g-PS) was carried out and a series of ion exchange membranes (PTFE-g-PSSA) was *** characterizations of FTIR,TGA,and SEM testified that grafting and sulphonation of the membranes were successfully processed;moreover,grafting of styrene not only occurred in the surface of PTFE membrane,but also in the micropores of the *** exchange capacity (IEC) and conductivity were found increase with the grafting *** results suggest that at a low dose,such as 17 kGy,the ion exchange membrane (IEM) which will be suitable for vanadium redox battery (VRB) use can be obtained.

关键词： PTFE-g-PSSA离子交换膜辐射合成性质钒氧化还原电池

Radiation-Assisted Synthesis of Crown Ether-Modified Covalent Organic Frameworks for lithium Isotope Separation

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CCS Chemistry 2024年第10期6卷 2594-2606页

作者： Shouchao Zhong Yue Wang Jianhui Lan Mingshu Xie Yiqian Wu jiuqiang li Fujian liu lilong Jiang Jing Peng liyong Yuan Maolin Zhai Weiqun Shi Radiochemistry and Radiation Chemistry Key Laboratory of Fundamental Science Key Laboratory of Polymer Chemistry and Physics of the Ministry of EducationCollege of Chemistry and Molecular EngineeringBeijing National Laboratory for Molecular SciencesPeking UniversityBeijing 100871 National Engineering Research Center of Chemical Fertilizer Catalyst College of Chemical EngineeringFuzhou UniversityFuzhou350002 Fujian Laboratory of Nuclear Energy Chemistry Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049

γ-ray radiation-induced grafting strategy was first employed to immobilize 4-aminobenzo-15-crown-5 onto a covalent organic framework(COF).This endeavor culminated in the successful synthesis of a class of two-dimensional crown ether-modified COFs(named[15C5]n%-(TzDa-G-x%)),marking the maiden utilization of COFs in the realm of^(6)li/^(7)li isotope *** COFs exhibited swifter adsorption kinetics than alternative *** them,[15C5]_(57%)-(TzDa-G-50%)with its excellent crystallinity,porosity,and stability exhibited the best performance in li+adsorption and^(6)li/^(7)li isotope *** li+adsorption in acetonitrile achieved a capacity of 3.6 mg·g^(−1)within 30 min and a saturation capacity of 7.3 mg·g^(−1).The single-stage separation factor of^(6)li/^(7)li isotopes was 1.014±*** results of dynamic adsorption column experiments showed that the packed column made of[15C5]_(57%)-(TzDa-G-50%)maintained stable performance during four cycles of li+adsorptionelution,with over 99%li+removal rate in *** crown ether-modified COF has potential application in^(6)li/^(7)li isotope separation,and this radiation-assisted synthesis strategy is expected to become universal in the modification of COFs for diverse applications.

关键词： covalent organic framework gamma radiation modification crown ether ^(6)li/^(7)li isotope separation adsorption column

明胶/聚丙烯酸/聚N-异丙基丙烯酰胺高强度形状记忆水凝胶的辐射合成及其性能

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辐射研究与辐射工艺学报 2020年第4期38卷 25-32页

作者：陈垦彭静李久强翟茂林北京大学化学与分子工程学院北京分子科学国家研究中心放射化学与辐射化学重点学科实验室北京100871

以明胶、丙烯酸、N-异丙基丙烯酰胺、N,N′-亚甲基双丙烯酰胺为原料,通过两步辐照法制备了具有温度和pH响应的高强度明胶/聚丙烯酸/聚N-异丙基丙烯酰胺形状记忆水凝胶(GAN)。系统研究了GAN的结构、形貌、力学性能和形状记忆行为。结果表... 详细信息

以明胶、丙烯酸、N-异丙基丙烯酰胺、N,N′-亚甲基双丙烯酰胺为原料,通过两步辐照法制备了具有温度和pH响应的高强度明胶/聚丙烯酸/聚N-异丙基丙烯酰胺形状记忆水凝胶(GAN)。系统研究了GAN的结构、形貌、力学性能和形状记忆行为。结果表明,GAN具有致密的网络结构,其最高拉伸强度及最大断裂伸长率分别可达(5.4±0.3)MPa和745%。GAN在60℃及pH=12.8的形状恢复所需时间分别为10 s及15 min,形状固定率和形状恢复率均在90%以上,显示出优异的环境响应性能。本工作建立了一种制备环境响应型高强度形状记忆水凝胶的新方法。

关键词：形状记忆水凝胶明胶丙烯酸 N-异丙基丙烯酰胺辐射合成

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壳聚糖在水溶液中的辐射降解反应

高分子学报 2006年第7期16卷 841-847页

作者：张志亮彭静黄凌翟茂林李久强魏根拴北京大学化学与分子工程学院北京100871

研究了壳聚糖在CH3COOH/NaCl缓冲溶液均相体系下的辐射降解反应,给出了H2O2、异丙醇、pH、样品初始分子量等因素对壳聚糖降解的影响,探讨了实验条件下溶液中不同自由基对壳聚糖降解的作用,并对辐照前后壳聚糖的结构进行了表征.结果表明... 详细信息

研究了壳聚糖在CH3COOH/NaCl缓冲溶液均相体系下的辐射降解反应,给出了H2O2、异丙醇、pH、样品初始分子量等因素对壳聚糖降解的影响,探讨了实验条件下溶液中不同自由基对壳聚糖降解的作用,并对辐照前后壳聚糖的结构进行了表征.结果表明,酸性条件下,壳聚糖的降解主要由.H和.OH自由基共同作用引起,加入H2O2或者通入N2O都能够略微提高.OH自由基浓度,对壳聚糖的降解有促进作用.加入异丙醇后,由于同时降低了.H和.OH自由基浓度,导致壳聚糖降解缓慢.当溶液的pH接近中性后,对壳聚糖的降解起主要作用的为.OH自由基,加入H2O2或者通入N2O都会增加.OH自由基的浓度,从而明显提高壳聚糖的降解速率.此外,研究发现低分子量的壳聚糖具有较快的降解速率.样品的UV、FTIR分析表明,辐照后除在壳聚糖分子链端生成羰基外,壳聚糖主链结构未见变化,脱乙酰度也没有显著改变,显示出辐射降解是一种有效的控制壳聚糖分子量方法.

关键词：壳聚糖辐射降解自由基化学结构

英国ACP3000型沥青混凝土搅拌站的改造

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工程机械 2009年第6期40卷 60-61页

作者：李久强黑龙江省龙建路桥第四工程有限公司

根据路桥建设发展的需要,目前大型沥青混凝土搅拌站的热料仓已由以往的4个仓发展成为5个或6个仓。我公司1997年购买的2台英国产ACP3000型沥青混凝土搅拌站,热料仓为4个,价

关键词：沥青混凝土搅拌站振动筛分机热料仓 ACP3000

Radiation grafting of styrene onto ETFE and subsequent sulphonation to prepare ion exchange membrane for vanadium redox battery use

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Radiation grafting of styrene onto ETFE and subsequent sulph...

The 1st Asian-Pacific Symposium on Radiation Chemistry

作者： Jingyi QIU Jiangfeng NI Maolin ZHAI Jing PENG Henghui ZHOU jiuqiang li Genshuan WEI College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

Using γ radiation technique, ETFE was grafted with styrene at room temperature and then the grafted membrane was sulfonated with chlorosulfonic acid into ETFE-g-PSSA ion exchange membrane. It was found that degree of grafting （DOG） increased with dose, and sulphonation was nearly 100%. Moreover, water uptake, ion exchange capacity （IEC） and conductivity of ETFE-g-PSSA membrane increased with DOG. FTIR spectra testified further that the grafting and sulfonation processes were successfully completed. TG analyses indicated that ETFE-g-PSSA membrane had good thermal stability, which could satisfy the requirement of vanadium redox battery （VRB）. Finally, ETFE-g-PSSA membrane with DOG of 43% was assembled in VRB and the charge-discharge performance was tested with a current of 100 mA. The capacity efficiency of the battery was calculated as 81.1%. Moreover, the decrease of the open circle voltage is very slow, which indicated slow permeability of vanadium ions. Consequently, at low dose of 20 kGy, the ion exchange membrane which was suitable for VRB use can be prepared. This new kind of ion exchange membrane will be investigated in detail in our following work.

关键词： ETFE radiation grafting, styrene ion exchange membrane vanadium redox battery

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核电厂核岛压力容器气压试验的方法研究

核动力工程 2023年第1期44卷 154-158页

作者：赵伟华邵春兵丰慧星谢剑芳江奎融李久强苏州热工研究院有限公司江苏苏州215004

法系核电厂核岛压力容器根据在役检查规范和大纲的要求需要实施定期水压试验,但部分容器由于系统设计的原因不能用液体实施水压试验,只能执行气压试验。本文对比分析了国内外规范对于气压试验的实施要求,并结合核岛安装阶段的气压试验过... 详细信息

法系核电厂核岛压力容器根据在役检查规范和大纲的要求需要实施定期水压试验,但部分容器由于系统设计的原因不能用液体实施水压试验,只能执行气压试验。本文对比分析了国内外规范对于气压试验的实施要求,并结合核岛安装阶段的气压试验过程,选定了核岛压力容器气压试验的试验压力、试验介质、验收标准等;同时结合容器水压试验的风险分析和辐射防护要求,制定气压试验的防护措施。根据以上试验参数与风险防护措施,在某核电厂核岛成功实施了压力容器气压试验,为后续的在役阶段核岛压力容器气压试验提供重要参考。

关键词：压力容器气压试验试验压力风险分析

三醋酸纤维素膜辐射可控接枝甲基丙烯酸缩水甘油酯及其性能

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应用化学 2020年第3期37卷 293-300页

作者：许晨曦曹明汉彭静李久强翟茂林北京大学化学与分子工程学院高分子化学与物理教育部重点实验室放射化学与辐射化学重点学科实验室北京分子科学国家研究中心北京100871

三醋酸纤维素(CTA)是一种高强度的天然高分子衍生物,对其进行表面接枝改性将扩展其在物质分离、吸附、检测等领域的广泛应用,但是化学接枝改性CTA比较困难。本文结合辐射引发接枝和可逆加成-断裂链转移(RAFT)聚合方法,成功地在CTA膜表... 详细信息

三醋酸纤维素(CTA)是一种高强度的天然高分子衍生物,对其进行表面接枝改性将扩展其在物质分离、吸附、检测等领域的广泛应用,但是化学接枝改性CTA比较困难。本文结合辐射引发接枝和可逆加成-断裂链转移(RAFT)聚合方法,成功地在CTA膜表面可控接枝了聚甲基丙烯酸缩水甘油酯(PGMA)。研究了吸收剂量、单体GMA质量分数和RAFT试剂含量等因素对接枝率的影响,采用傅里叶变换红外光谱仪(FT-IR)、扫描电子显微镜(SEM)和接触角技术手段对CTA膜接枝前后的结构、形貌和表面性质进行了表征。实验结果表明,为了得到较高的接枝率,同时又保持较好的形貌,合适的条件为:吸收剂量为10~12 kGy,GMA质量分数为30%,RAFT试剂与GMA的物质的量比为1∶400;在不同条件下得到的最高接枝率为41%,接枝聚合物相对分子质量分布最低为1.33。此外,接枝PGMA后的CTA膜疏水性增加。该工作提供了可控接枝CTA的简便方法,与传统辐射接枝相比,RAFT辅助辐射接枝反应更加可控,得到的PGMA接枝链更加均匀,有利于根据实际应用来控制接枝率和进行后续的功能修饰。

关键词：三醋酸纤维素辐射接枝可逆加成-断裂链转移