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Gound State Properties of Nuclei in ^(295)118 α-Decay Chain

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Communications in Theoretical Physics 2009年第12期52卷 1055-1061页

作者： dong jian-min ZHANG Hong-Fei ZUO Wei WANG Yan-Zhao LI Jun-Qing School of Nuclear Science and Technology Lanzhou University Lanzhou 730000 China Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China

The properties of nuclei belonging to the α-decay chain of superheavy element ^295118 have been studied in the framework of axially deformed relativistic mean field （RMF） theory with the parameter set of NL-Z2 in the blocked BCS approximation. Some ground state properties such as binding energies, deformations, and α-decay energies Qα have been obtained and agree well with those from finite-range droplet model （FRDM）. The single-particle spectra of nuclei in ^295118 α-decay chain show that the shell gaps present obviously nucleon number dependence. The root-mean-square （rms） radii of proton, neutron and matter distributions change slowly from ^283112 to ^295118 but dramatically from ^279110 to ^283112, which may be due to the subshell closure at Z = 110 in ^279110. The α-decay half-lives in 295118 decay chain are evaluated by employing the cluster model and the generalized liquid drop model （GLDM）, and the overall agreement is found when they are compared with the known experimental data. The α-decay lifetimes obtained from the cluster model are slightly larger than those of GLDM ones. Finally, we predict the α-decay half-lives of Z=118, 116, 114, 112 isotopes using the cluster model and GLDM, which also indicate these two models can corroborate each other in studies on superheavy nuclei. The results from GLDM are always lower than those obtained from the cluster model.

关键词： superheavy nuclei relativistic mean field half-lives cluster model generalized liquid drop model

Effects of Aging and Advanced Glycation on Gene Expression in Cerebrum and Spleen of Mice

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Biomedical and Environmental Sciences 2003年第4期16卷 323-332页

作者： YUE-XIN LIANG, ZHEN WANG, DIAN-dong LI, jian-min jianG,AND RONG-GUANG SHAOInstitute of Medicinal Biotechnology, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

Objective To analyze the effects of aging or advanced glycation on gene expression in the cerebrum and spleen of female C57BL/6J mice. Methods The gene expression profile was determined by using cDNA expression arrays containing 588 cDNA. Results Aging and advanced glycation resulted in differential gene expression patterns of cerebrum and spleen compared with young mice. Among the 80 genes detected in cerebrum, 43 exhibited a change in mRNA ratios with aging or treatment. Thirty-four changes (79%) were common in aged and D-galactose treated mice, whereas the cerebrum from aged and AGE-lysine treated mice showed common changes in expression of 38 genes (88%). Of the 86 genes detected in spleen, 29 (34%) displayed an age-related decrease in expression, whereas 3 (3%) displayed an increase in expression levels with aging. Eighteen genes from the detectable genes exhibited expression changes in both cerebrum and spleen of mice. Conclusions The gene expression profiles of D-galactose and AGE-lysine treated mice resemble those of aged mice. Use of cDNA hybridization arrays may provide a promising tool to explore the mechanism of aging at a molecular level.

关键词： Aging Galactose Advanced glycation Gene expression DNA microarrays Cerebrum Spleen

Properties ofαDecay to Rotational Bands of Heavy Nuclei

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Properties ofαDecay to Rotational Bands of Heavy Nuclei

Branching Ratios ofαDecay for Heavy Nuclei Near Deformed Shell Closures

作者： WANG Yan-zhao PENG Bang-bao dong jian-min GU jian-zhong Institute of Modern Physics Chinese Academy of Sciences

The a radioactivity has been explained successfully by Gamow and by Condon and Gurney as a quantum tunneling *** the basis of Gamow’s theory,the experimentalα-decay half-lives of nuclei can be explained by both phenomenological and microscopic *** a long time,theoretical investigation on a-decay has mainly concentrated on the favored cases,e.g.,the ground state a transitions of even-even *** addition to the favored a transitions,the ground states of the parent nucleus can also decay to the excited states of the daughter *** a transitions belong to the unfavored cases,which are strongly hindered compared to the favored *** is important to study such transitions experimentally to build the level schemes of daughter ***,the hinderedαtransition is an effective tool to study the

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Branching Ratios ofαDecay for Heavy Nuclei Near Deformed Sh...

Self-expanding metallic stents drainage for acute proximal colon obstruction

作者： WANG Yan-zhao PENG Bang-bao dong jian-min GU jian-zhong Institute of Modern Physics Chinese Academy of Sciences

Nowadays,the study on the deformation of heavy nuclei and super-heavy nuclei(SHN) is a hot subject in nuclear physics.A number of heavy nuclei and SHN around Hs have already been observed *** theoretical study of deformed SHN suggests that Hs is a doubly magic deformed ***,there is no experimental evidence for the deformed shapes of the above-mentioned *** such evidence would be of great *** would confirm the unexpected structure of these *** 2001,Sobiczewski et *** to observe the refined structure of the decay to a rotational spectrum of the daughter nucleus to extract information on heavy nuclei and SHN deformation.

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World Journal of Gastroenterology 2011年第28期17卷 3342-3346页

作者： Li-Qin Yao Yun-Shi Zhong Mei-dong Xu jian-min Xu Ping-Hong Zhou Xian-Li Cai Department of Endoscopic Center Zhongshan Hospital Fudan University Medical Center Shanghai200032 China

AIM: To clarify the usefulness of the self-expanding metallic stents (SEMS) in the management of acute proximal colon obstruction due to colon carcinoma before curative ***: Eighty-one colon (proximal to spleen flex) carcinoma patients (47 males and 34 females,aged 18-94 years,mean = 66.2 years) treated between September 2004 and June 2010 for acute colon obstruction were enrolled to this study,and their clinical and radiological features were *** a cleaning enema was administered,urgent colonoscopy was ***,endoscopic decompression using SEMS placement was ***: Endoscopic decompression using SEMS placement was technically successful in 78 (96.3%) of 81 *** patients’ symptoms could not be relieved after SEMS placement and emergent operation was performed 1 d *** site of obstruction was transverse colon in 18 patients,the hepatic flex in 42,and the ascending colon in *** adequate cleansing of the colon,patients’ abdominal girth was decreased from 88 ± 3 cm before drainage to 72 ± 6 cm 7 d later,and one-stage surgery after 8 ± 1 d (range,7-10 d) was *** anastomotic leakage or postoperative stenosis occurred after ***: SEMS placement is effective and safe in the management of acute proximal colon obstruction due to colon carcinoma,and is considered as a bridged method before curative surgery.

关键词： Endoscope Proximal colon cancer Obstruction Self-expanding metallic stents Drainage

聚四氟乙烯/共价功能化氮化硼复合材料的制备以及摩擦性能研究

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塑料科技 2022年第7期50卷 77-80页

作者：董建民山东工业职业学院山东淄博256414

采用聚多巴胺(PDA)功能化的六方氮化硼(h-BN)作为填料与聚四氟乙烯(PTFE)进行复合,制备PTFE/改性BN(PTFE/MBN)复合材料,并对PTFE/MBN的拉伸强度、硬度以及摩擦性能进行了研究。结果表明:MBN具有优异的分散性能。PTFE/MBN-15%的拉伸强度... 详细信息

采用聚多巴胺(PDA)功能化的六方氮化硼(h-BN)作为填料与聚四氟乙烯(PTFE)进行复合,制备PTFE/改性BN(PTFE/MBN)复合材料,并对PTFE/MBN的拉伸强度、硬度以及摩擦性能进行了研究。结果表明:MBN具有优异的分散性能。PTFE/MBN-15%的拉伸强度为21.3 MPa,硬度为7.1,均优于未改性BN填充PTFE。摩擦性能方面,PTFE/MBN-15%的平均摩擦系数最低,为0.068,并且磨痕形貌显示MBN具有较好的减磨作用。PTFE/MBN-15%具有优异的耐老化性能。因此,制备的PTFE/MBN复合材料可以有效拓展PTFE在摩擦领域的应用。

关键词：氮化硼聚四氟乙烯功能化改性摩擦性能

检验腐蚀对镍基单晶高温合金高周疲劳性能的影响

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材料工程 2020年第1期48卷 77-83页

作者：董建民李嘉荣韩梅中国航发北京航空材料研究院先进高温结构材料重点实验室

为了研究检验腐蚀对一种镍基单晶高温合金高周疲劳性能的影响,将经过标准热处理的试样置于FeCl 3+HCl+H 2O腐蚀剂中分别腐蚀2次和4次,采用莱卡DCM8共聚焦显微镜和扫描电镜对未腐蚀、2次与4次腐蚀试样的表面形貌进行观察,然后分别测试未... 详细信息

为了研究检验腐蚀对一种镍基单晶高温合金高周疲劳性能的影响,将经过标准热处理的试样置于FeCl 3+HCl+H 2O腐蚀剂中分别腐蚀2次和4次,采用莱卡DCM8共聚焦显微镜和扫描电镜对未腐蚀、2次与4次腐蚀试样的表面形貌进行观察,然后分别测试未腐蚀和4次腐蚀试样760℃与980℃的旋转弯曲疲劳性能。结果表明:未腐蚀试样表面存在纵向且相互平行的由抛光带来的细小抛痕,表面粗糙度低;2次腐蚀后,表面抛痕有所减少,枝晶间区域出现腐蚀坑,表面粗糙度增加;4次腐蚀后,表面抛痕被完全腐蚀掉,腐蚀坑深度和表面粗糙度进一步增加。4次腐蚀会略微降低合金760℃的疲劳性能,但对高应力幅条件下的疲劳寿命影响较大,对低应力幅条件下的疲劳寿命影响较小。4次腐蚀对合金980℃疲劳性能影响很小。

关键词：单晶高温合金腐蚀疲劳表面完整性

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太阳引力场中的二阶后牛顿光线方程

山东大学学报（理学版） 2005年第2期40卷 79-83页

作者：宫衍香董建敏泰山学院物理系山东泰安271021 山东大学物理与微电子学院山东济南250100

从含有14个后牛顿参数的太阳度规张量出发,采用一套迭代的方法,推导出了太阳单参考系下的二阶后牛顿光线方程;当其中所含的参数取特定的值时,得到广义相对论中的二阶后牛顿光线方程;当忽略高于1 c4 的项时。

关键词：太阳度规二阶后牛顿近似光线方程迭代方法

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喷丸对DD6单晶高温合金拉伸性能的影响

材料工程 2019年第8期47卷 169-175页

作者：韩梅喻健李嘉荣谢洪吉董建民杨岩中国航发北京航空材料研究院先进高温结构材料重点实验室北京100095 陆军航空兵军事代表局驻北京地区军事代表室北京100095

采用扫描电子显微镜(SEM)、X射线(X-ray)和透射电子显微镜(TEM)等手段研究铸钢丸喷丸对第二代单晶高温合金DD6在500,600,650℃拉伸性能的影响。结果表明:500,600,650℃时,喷丸对DD6合金抗拉强度影响不大,略微提高屈服强度,显著降低伸长... 详细信息

采用扫描电子显微镜(SEM)、X射线(X-ray)和透射电子显微镜(TEM)等手段研究铸钢丸喷丸对第二代单晶高温合金DD6在500,600,650℃拉伸性能的影响。结果表明:500,600,650℃时,喷丸对DD6合金抗拉强度影响不大,略微提高屈服强度,显著降低伸长率和断面收缩率。喷丸DD6合金在流变应力上升到最高点后断裂,试样拉伸断裂后的横截面为圆形;未喷丸DD6合金拉伸曲线呈现双重阶段特征,试样拉伸断裂后的横截面为椭圆形。

关键词： DD6 单晶高温合金喷丸拉伸性能显微组织