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VISCOELASTIC BEHAVIOR OF THE NON-HOOKE DEFORMATION BEFORE YIELDING IN UNIAXIAL DRAWING OF AMORPHOUS POLY(ETHYLENE TEREPHTHALATE)

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Chinese Journal of Polymer Science 2001年第4期19卷 399-405页

作者： Zhen-hua Yuan De-yan Shen Ren-yuan Qian Polymer physics laboratory Center for Molecular Science, Institute of Chemistry Chinese Academy of Sciences, beijing 100080{3. 中科院化学所高分子物理及化学国家重点实验室北京

Viscoelastic behavior of the non-Hooke deformation of amorphous PET film before yield was investigated in the temperature region 74-80.5 degreesC around the glass transition temperature. The film specimen was drawn to yield point followed by unloading to zero stress, then the residual deformation was held constant; while the subsequent evolution of the stress was recorded. An induction period was found in the course of stress evolution followed by a stress step-increase. The induction period decreases with increasing drawing temperature with an activation energy of 1.10 MJ/mol.K, which is attributed to the time needed for the relaxation of rubbery deformation through cooperative internal rotations. At temperatures lower than 74 degreesC, there is no stress increase or the induction period becomes too long to be observed. Thus the nature of anelasticity in the non-Hooke region before yielding is attributed to stress induced rubbery deformation. The experimental results are interpreted in terms of Perez' theological model of a series connected Hooks spring and a Voigt element consisting of a parallel connected elastic spring and a dashpot.

关键词： pre-yield deformation PET uniaxial drawing non-Hooke deformation viscoelasticity stress induced rubbery deformation

石墨烯量子霍尔平台与平台之间转变的标度律关系

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物理学报 2011年第10期60卷 585-588页

作者：谭振兵马丽刘广同吕力杨昌黎中国科学院物理研究所北京凝聚态物理国家实验室北京100190

在2到50K温度范围内测量了单层石墨烯量子霍尔平台与平台之间转变的标度律关系.发现石墨烯的标度律指数κ不是普适的,在低温段的κ大约是0.13.在高温段的κ大约是0.3..这一结果进一步验证了石墨烯中长程散射的主导地位.

关键词：石墨烯量子霍尔效应标度律

Fabricating graphene nanoribbons by straightforward nanosphere lithography:en route to “on-chip” band-gap engineering of graphene

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Fabricating graphene nanoribbons by straightforward nanosphe...

2011中国材料研讨会

作者： Lei Liu,Yingli Zhang,Wenlong Wang,Changzhi Gu,Xuedong Bai,and Enge Wang beijing national laboratory for condensed matter physics,Institute of physics,Chinese Academy of Sciences,beijing{3.,china,and School of physics,Peking University,beijing 100871,china

＜正＞Graphene nanoribbons（GNRs）have been received special attention due to quantum confinement and edge effect,which provides possibilities to confine carriers electrostatically

关键词： Graphene nanoribbions nanosphere lithography band-gap engineering

随机表面散射光场的格林函数法与基尔霍夫近似的比较

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物理学报 2004年第2期53卷 427-435页

作者：刘春香程传福任晓荣刘曼滕树云徐至展中国科学院物理研究所和凝聚态物理中心光物理实验室北京100080 中国科学院上海光学与精密机械研究所上海201800 山东师范大学物理系济南250014

从简谐光波满足的亥姆霍兹方程出发 ,将由格林定理得到的介质分界面上的积分方程转化为以表面上的光波及其导数为未知量的线性方程组 ,并对其进行数值求解 ,实现了光场的数值计算 .同时 ,由透射光场的格林函数积分得出了基尔霍夫近似下... 详细信息

从简谐光波满足的亥姆霍兹方程出发 ,将由格林定理得到的介质分界面上的积分方程转化为以表面上的光波及其导数为未知量的线性方程组 ,并对其进行数值求解 ,实现了光场的数值计算 .同时 ,由透射光场的格林函数积分得出了基尔霍夫近似下光场的表达式 .通过类比推导夫琅和费面上散斑场自相关函数的方法 ,提出了产生随机表面及其导数的傅里叶变换方法 .在此基础上 ,对采用基尔霍夫近似进行自仿射分形随机表面的散射光场数值计算的精确程度进行了研究 .发现在随机表面粗糙度比较小时 ,基尔霍夫近似的精度比较高 ;在粗糙度相同的情况下 ,表面的分形维数越小 ,基尔霍夫近似的精度越高 .

关键词：随机表面散射光场格林函数积分基尔霍夫近似简谐光波亥姆霍兹方程透射光场夫琅和费面自相关函数傅里叶变换

POLYMETHYLMETHACRYLATE FILMS IN THE STATE OF HIGH GLOBAL CHAIN ORIENTATION BUT NEARLY RANDOM SEGMENTAL ORIENTATION

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Chinese Journal of Polymer Science 1999年第3期17卷 215-220页

作者： Rui Song Jing Chen Jin-gui Gao Xin Lin Qing-rong Fan Polymer physics laboratory, Institute of Chemistry, Chinese Academy of Sciences, beijing 100080,{3. 中科院化学所高分子物理及化学国家重点实验室北京 100080 中科院化学所高分子物理及化学国家重点实验室北京

PMMA films in the high global chain orientation and nearly random segmental orientation (GOLR) state were prepared by uni-axially drawing at temperatures 20 similar to 3. degrees C above its glass transition temperature, T-g, and their isotropic and anisotropic properties were studied. Experimental results show that this kind of amorphous state, the GOLR state, is nearly isotropic in optical birefringence, IR-dichroism and X-ray diffraction patterns, but is very anisotropic in behaviors of thermal expansion, solvent-swelling and stress-strain.

关键词： orientation uniaxial stretching polymethylmethacrylate optical birefringence WAXD infrared spectroscopy

Fabrication and Characterization of GCO Electrolyte Films

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稀有金属材料与工程 2006年第S3期 530-532页

作者： Yuxing Xu~1 Zilong Tang~1 Zhongtai Zhang~1 Zhigang Zhou~1 Lihai Xu~2 (1.State Key laboratory of New Ceramic and Fine Processing,Department of Materials Science and Engineering,Tsinghua University,beijing 100084,china) (2.Center of{3. matter physics and Material physics,School of Science,Beihang University,beijing 100083.china)

Gd-doped Ceria (GCO:Gd0.1Ce0.9O1.95) sensing films have been fabricated successfully on glasses and porous Al2O3.eramic substrates by RF magnetron *** conditions such as power and temperature have been investigated and the sample was characterized in detail by XRD,SEM and AC impedance *** results show that the films grow preferentially along the （111） compact plane with a pure fluorite structure and the crystal grain grows more sufficiently with increasing of the annealing *** addition,a high oxygen ion conductivity of 2.24×***-1is achieved at 800℃.

关键词： electrolyte film GCO RF magnetron sputtering oxygen conductivity

Monolithic CEO-stabilization scheme-based frequency comb from an octave-spanning laser

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Chinese physics B 2016年第4期25卷 150-153页

作者：于子蛟韩海年谢阳滕浩王兆华魏志义 beijing national laboratory for condensed matter physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of physics and Optoelectronics Engineering Xidian UniversityXi'an 710071China

We demonstrate a carder-envelope phase-stabilized octave-spanning oscillator based on the monolithic scheme. A wide output spectrum extending from 480 nm to 1050 nm was generated directly from an all-chirped mirror Ti：sapphire laser. After several improvements, the carder-envelope offset （CEO） beat frequency accessed nearly 60 dB under a reso- lution of 100 kHz. Using a feedback system with 50-kHz bandwidth, we compressed the residual phase noise to 55 mrad （integrated from 1 Hz to 1 MHz） for the stabilized CEO, corresponding to 23.as timing jitter at the central wavelength of 790 nm. This is, to the best of our knowledge, the smallest timing jitter achieved among the existing octave-spanning laser based frequency combs.

关键词： octave-spanning laser optical frequency comb carrier-envelope offset low phase noise

A comparative study of magnetic properties between whole cells and isolated magnetosomes of Magnetospirillum magneticum AMB-1

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A comparative study of magnetic properties between whole cel...

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： LI JinHua~(1,2,3.,PAN YongXin~(1,3.),LIU QingSong~(3.4),QIN HuaFeng~4,DENG ChengLong~4, CHE RenChao~5 & YANG XinAn~5 1 Key laboratory of the Earth’s Deep Interior,Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing 100029,{3. 2 Graduate University of Chinese Academy of Sciences,beijing 100049,{3. 3.Franco-Chinese Biomineralization and Nano-structures laboratory,beijing 100029,{3. 4 State Key laboratory of Lithospheric Evolution,Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing 100029,{3. 5 {13.,Institute of physics,Chinese Academy of Sciences,beijing 100080,{3.

The magnetic properties of magnetosome magnetite are of interdisciplinary interest because magnetosomes are potential carriers of natural remanent magnetization and paleoenvironment,as well as novel nano-biomaterials in biotechnological and biomedical *** carried out magnetic and electron transmission microscopy analyses of fresh Magnetospirillum magneticum AMB-1 whole cells and isolated *** revealed that AMB-1 synthesized single-domain magnetite magneto-somes, which are arranged in the form of linear fragmental *** distinct differences of magnetic properties between these two samples can be faithfully interpreted in terms of spatial arrangement of magnetosomes and magnetostatic *** the whole cells,the strong intra-chain interactions and weak inter-chain interactions generate behaviors of non-interacting uniaxial single-domain ***δ-ratio is 3.0 and passes the Moskowitz *** contrast,the isolated magnetosome sample has reduced values of coercivity andδ-ratio(1.5),due to increasing three-dimensional magnetostatic interactions and collapse of magnetosome *** observations provide useful insights into applications of the biogenic magnetite(magnetosomes)in magnetic nano-materials and magnetofossils in the paleomagnetic and environmental magnetism.

关键词： Magnetospirillum magneticum AMB-1 isolated magnetosomes hysteresis loop FORC Verwey transition Moskowitz test

Ab initio-based DMBE potential energy surface for the electronic ground state of ammonia

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Ab initio-based DMBE potential energy surface for the electr...

第十六届全国原子与分子物理学术会议

作者： Yong-Qing.Li~(a,*),Meng-Tao Sun~(b,♂),Feng-Cai Ma~a a.Department of physics Liaoning University,Shenyang 11003.,china b.beijing national laboratory for condensed matter physics,Institute of physics,Chinese Academy of Sciences,beijing 100190,china

A single-sheeted Ab initio-based global DMBE(double many-body expansion) [1-4]potential energy surface is reported for the ground electronic state of NH3.5].It employs realistic DMBE functions previously reported from accurate ab initio data for the triatomic fragments plus four-body energy terms that have been calibrated from

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