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FABRICATION OF PIEZOElECTRIC BIMORPH USING lEAD ZIRCONATE TITANATE THIN FIlM DEPOSITED BY HYDROTHERMAl METHOD

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Chinese Journal of Mechanical Engineering 2007年第6期20卷 5-8页

作者： DU liqun lü Yan DONG Weijie GAO Xiaoguang Key laboratory for Precision ＆ Nontraditional Machining Technology of Ministry of Education Dalian University of Technology Dalian 116023 China School of Electronic and Information Engineering Dalian University of Technology Dalian 116023 China Key laboratory for Micro/Nano Technology and System Dalian University of Technology Dalian 116023 China

In order to describe the characteristics of piezoelectric bimorph, properties of lead zirconate titanate （lZT） film are studied by X-ray diffraction （XRD） and scanning eletron microscope （SEM）. The ratio of PbTiOJPbZrO3 in lZT is 53/47, which is around morphotropic phase boundary （MPB）. lZT film is composed of cubic particles with the average size of 5 ~ma. Density of thin film is figured out through the datum measured in experiments. The displacement model used to analyze the driving ability of bimorph is set up, and the effect of elastic intermediate layer is taken into account. Piezoelectric coefficient of lZT film is worked out by using the displacement model. Experiments of driving ability show that deformation of bimorph free end does not increase with times of crystal growth processes and the maximum deformation is obtained after two times crystal growth processes. Finally, the ferroelectric property of the bimorph is investigated and coercive voltage of the bimorph is obtained.

关键词： Piezoelectric bimorph lead zirconate titanate (lZT) film Hydrothermal method

Micromechanics behavior of fatigue cracks in Hadfield steel railway crossing

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Science China(Technological Sciences) 2013年第5期56卷 1151-1154页

作者： FENG XiaoYong ZHANG FuCheng ZHENG Chunlei l Bo State Key laboratory of Metastable Materials Science and Technology Yanshan University

In order to predict the mechanism of the formation and propagation of rolling contact fatigue cracks in Hadfield steel railway crossings(HSRC),the residual strain,microstructure,crystal orientation,and microhardness surrounding fatigue cracks were *** show that the formation and propagation of fatigue cracks in HSRC have no correlation with the crystal orientation and boundaries of *** hardness and residual strain in the field around the fatigue crack are lower than those in other *** compressive strain around the fatigue crack is released after crack propagates,which reduces the hardness around the fatigue *** twins and dislocations play a key role in the work hardening of HSRC.

关键词： hadfield steel EBSD residual strain work hardening fatigue cracks

crystal Structure and Magnetic Studies of a New Nitronyl Nitroxide Compound

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Chinese Chemical.letters 2000年第8期11卷 749-752页

作者： Ding, l Zhang, DQ Zhang, B Zhu, DB Chinese Acad Sci Ctr Mol Sci Inst Chem Organ Solids Lab Beijing 100080 Peoples R China

Compound 1 was first synthesized and characterized. Its crystal structure and magnetic property were determined and investigated. Discussion about the molecule packing in crystal and the macroscopic magnetism was also... 详细信息

关键词： nitronyl nitroxide crystal structure spin density magneto-structural relationship

Pressure-dependent phase transition of 2D layered silicon telluride(Si2le3)and manganese intercalated silicon telluride

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Nano Research 2019年第9期12卷 2373-2377页

作者： Virginia l. Johnson Auddy Anilao Kristie J. Koski Department of Chemistry University of CaliforniaDavisDavisCA 95616USA

Two-dimensional(2D)layered silicon telluride(SizTes)nanocrystals were compressed to 12 GPa using diamond anvil cell *** measurements show a color change from transparent red to opaque black indicating a semiconductor-to-metal phase *** scattering was used to observe the stiffening of the crystal lattice and subsequent phase behavior.A possible phase transition was *** 9.5±0.5 GPa evidenced by the disappearance of the Atg stretching *** was intercalated with elemental manganese to^1 at.%.Intercalation lowers the pressure of the proposed phase transition to 7.5±1 *** modes show both phonon stiffening and phonon softening,suggesting negative linear *** results provide fundamental insight into the high-pressure optical phonon behavior of silicon telluride and illuminate how a specific electron-donating intercalant can chemically alter pressure-dependent optical phonon behavior.

关键词： silicon telluride Si2Te3 high pressure diamond anvil cell two-dimensional(2D)layered material

Synthesis and crystal structure of a neodymium coordination polymer with 2,6-anthraquinonedisulfonate

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Particuology 2010年第3期8卷 221-224页

作者： Jennifer l. Nicholls John Bacsa Andrew M. Fogg Department of Chemistry University of Liverpool Crown Street Liverpool L69 7ZD United Kingdom

The coordination polymer, （Nd（H2O）5）2（2,6-AQDS）3.2H2O where 2,6-AQDS = 2,6- anthraquinonedisulfonate, has been synthesised via a hydrothermal route. Structurally, it consists of layers of monomeric Nd polyhedra which are linked by 2,6-AQDS anions forming a polymeric, three-dimensional network. Each Nd atom is nine coordinate, bonding to five water molecules and to four oxygen atoms from four 2,6-AODS anions which in turn pillar the layers by bridging two Nd atoms in one layer, and coordinating to a single Nd in the other.

关键词： lanthanide layered materials Sulfonate Coordination polymer

Random crystal field effect on hysteresis loops and compensation behavior of mixed spin-(1,3/2) Ising system

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Chinese Physics B 2017年第12期26卷 538-547页

作者： K Htoutou Y Benhouria A Oubelkacem R Ahl.laamara l B Drissi lPHE-Modeling and Simulations Faculty of Sciences Mohammed V University in Rabat Morocco Center Regional des Metiers de l'Education et de la Formation (CRMEF) Fes-Meknes Marocco lP2MS University of Moulay Ismail Faculty of Sciences Meknes Morocco Center of Physics and Mathematics CPM-Morocco

Magnetic hysteresis and compensation behavior of a mixed spin-（1, 3/2） Ising model on a square lattice are investigated in the framework of effective field theory based on a probability distribution technique. The effect of random crystal field, ferromagnetic and ferrimagnetic exchange interaction on hysteresis loops and compensation phenomenon are discussed. A number of characteristic phenomena have been reported such as the observation of triple hysteresis loops at low temperatures and for negative values of random crystal field. Critical and double compensation temperatures have been also found. The obtained results are also compared to some previous works.

关键词： ferrimagnetic mixed Ising system effective field theory hysteresis loops compensation behaviors

Three-dimensional Weyl topology in one-dimensional photonic structures

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light(Science & Applications) 2022年第7期11卷 1337-1338页

作者： Kosmas l.Tsakmakidis Tomasz P.Stefański Section of Condensed Matter Physics Department of PhysicsNational and Kapodistrian University of AthensPanepistimioupolisGR-15784 AthensGreece Faculty of Electronics Telecommunicationsand InformaticsGdansk University of Technology80-233 GdanskPoland

Topological features,in particular distinct band intersections known as nodal rings,usually requiring three-dimensional structures,have now been demonstrated experimentally in an elegantly simple one-dimensional photo... 详细信息

关键词： crystal. dimensional topology

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基于右旋糖酐酶制备小麦多孔淀粉及其特性

食品工业科技 2024年第3期45卷 123-129页

作者：王博岩李强吴一卓章均哲吴旭东张磊吕明生王淑军江苏省海洋生物资源与环境重点实验室江苏海洋大学江苏连云港222005 江苏省海洋生物技术重点实验室江苏海洋大学江苏连云港222005 海阳市市场监督管理局山东烟台265100

生物酶法制备多孔淀粉条件温和、工艺简单和绿色环保。本研究选用特异性水解α-1,6糖苷键的右旋糖酐酶制备小麦多孔淀粉。通过X-晶体射线衍射、傅里叶红外光谱、扫描电镜和粒度分析仪对淀粉的结构进行表征,同时测定了淀粉膨胀率、吸水... 详细信息

生物酶法制备多孔淀粉条件温和、工艺简单和绿色环保。本研究选用特异性水解α-1,6糖苷键的右旋糖酐酶制备小麦多孔淀粉。通过X-晶体射线衍射、傅里叶红外光谱、扫描电镜和粒度分析仪对淀粉的结构进行表征,同时测定了淀粉膨胀率、吸水和吸油率、药品负载率和体外溶出等指标。结果表明:在温度为50℃条件下处理16 h、小麦淀粉的表面形成孔洞,淀粉粒径减小,多孔淀粉的晶型结构无显著变化。多孔淀粉的比容积为2.11±0.02 cm^(3)/g、溶解度为9.02%±0.21%、膨胀度达到了9.91%±0.22%、吸水率和吸油率分别提高到80.12%和78.23%;多孔淀粉与姜黄素、甲磺酸达比加群酯、制霉菌素和氧氟沙星四种药品在160:1的比例下负载率平均达到了75.07%。体外试验显示,小麦多孔淀粉负载姜黄素的释放率显著降低。在胃液中2.5 h的释放率约为30%。在肠液中5 h的释放率约为40%。研究结果为小麦多孔淀粉的制备和应用提高的依据。

关键词：小麦淀粉右旋糖酐酶多孔淀粉药物负载

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Numerical Simulation of the Scavenging Rates of Ice crystals of Various Microphysical Characteristics

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Advances in Atmospheric Sciences 1991年第2期8卷 175-200页

作者： Richard l. Pitter Renyi Zhang Atmospheric Sciences Center Desert Research Institute University of Nevada System Reno Nevada 89506 U. S. A.Atmospheric Sciences Center Desert Research Institute University of Nevada System Reno Nevada 89506 U. S. A.

Numerical models of trajectories of small aerosol spheres relative to oblate spheroids were used to determine ice crystal scavenging efficiencies. The models included the effects of aerodynamic flow about the ice particle, gravity, aerosol particle inertia and drag and electrostatic effects. Two electric configurations of the ice particle were investigated in detail. The first applied a net charge to the ice particle, of magnitude equal to the mean thunderstorm charge distribution, while the second applied a charge distribution, with no net charge, to the ice particle to model the electric multipole charge distribution. The results show that growing ice crystals with electric multipoles are better scavengers than single ice crystals with net thunderstorm charges, especially in the Greenfield gap (0.1 to 1.0 um), and that larger single crystals are better scavengers than smaller single crystals. The results also show that the low density ice crystals are more effective scavengers with net charges than they are with charge distribution.

关键词： Numerical Simulation of the Scavenging Rates of Ice crystals of Various Microphysical Characteristics