材料期刊网

Synchronizing the Parameter Non-matching Chaotic Systems

Shouliang BU , Shaoqing WANG , Hengqiang YE

材料科学技术（英文）

It is shown that synchronization, in a weak sense, can be achieved between two-parameter non-matching systems by using the adaptive control method. In essence, this requires just a scalar signal transmitted from the drive to the response system. Two typical chaotic systems, i.e., Lorenz and Rőssler system, are taken as examples of applications in this paper.

关键词: Chaotic systems , null , null

Fe(acac)3-Al(i-Bu)3对马来酸酐与茴香脑共聚的催化性能

杨科芳 , 房江华 , 高连勋

催化学报

研究了Fe(acac)3-Al(I-Bu)3(acac=乙酰丙酮)催化体系对马来酸酐(MA)与茴香脑(ANE)共聚反应的催化性能. 动力学研究结果表明,MA与ANE共聚对单体的浓度呈一级反应,其表观活化能为31.0 kJ/mol. 用IR和13C NMR研究了共聚物的结构,结果表明聚合物是交替的,其中酸酐的含量为45.6%. 用GPC测定了聚合物的分子量及其分布,结果表明分子量的分布较窄,PDI=1.19～1.42. 用DTA研究了聚合物的热力学性质,其分解温度为501.1 ℃.

关键词: 乙酰丙酮铁 , 三异丁基铝 , 马来酸酐 , 茴香脑 , 共聚反应

Fe(acac)3-Al(i-Bu)3-CCl4催化马来酸酐与降冰片烯共聚

房江华 , 杨科芳 , 胡富陶

催化学报

研究了Fe(acac)3-Al(i-Bu)3-CCl4 (acac=乙酰丙酮)催化体系对马来酸酐(MA)与降冰片烯(NBE)交替聚合反应的催化性能. 用元素分析、核磁共振和红外光谱研究了共聚物的结构,在单体比为1∶1时,共聚物中MA和NBE的含量分别为52.2%和47.8%. 凝胶渗透色谱结果表明共聚物分子量分布窄. 动力学研究结果表明, MA与NBE共聚对单体浓度呈一级反应,其表观活化能为74.3 kJ/mol.

关键词: 乙酰丙酮铁 , 三异丁基铝 , 四氯化碳 , 马来酸酐 , 降冰片烯 , 共聚反应

Fe(acac)3-Al(i-Bu)3催化马来酸酐与异戊二烯共聚合研究

房江华 , 杨科芳

高分子材料科学与工程

研究了双金属体系Fe(acac)3-Al(i-Bu)3催化马来酸酐与异戊二烯的共聚反应.结果表明,在甲苯/二氧六环=2/5的混合溶剂中反应2 h,共聚物的收率为78.3%,溶解性实验表明,共聚物不溶于氯仿、丙酮、四氢呋喃等溶剂,但在极性溶剂如二氧六环中共聚,得到微溶于四氢呋喃的共聚物.用红外光谱、核磁共振、元素分析测定了共聚物的结构及组成.

关键词: 乙酰丙酮铁 , 三异丁基铝 , 马来酸酐 , 异戊二烯 , 共聚

丙烯酸十八酯在Nd(P204)3-Al(i-Bu)3催化剂体系中聚合的研究

丁伟 , 张一烽 , 沈之荃

高分子材料科学与工程

研究了丙烯酸十八酯(OA)在Nd(P204)3-Al(i-Bu)3催化剂体系中的聚合反应,反应的最佳条件是:以苯为溶剂,［Al］／［Nd］=9(摩尔比),［OA］／［Nd］=162(摩尔比),60 ℃反应6 h,聚合转化率大于90%,所得聚合物的分子量为1.0×105～1.5×105。聚合反应速率与单体浓度、催化剂浓度均呈一级关系,聚合反应的表观活化能为32.5 kJ／mol。

关键词: 丙烯酸十八酯 , 稀土配位催化剂 , 聚合动力学 , 配位聚合

Nd(acac)3-Al(i-Bu)3催化邻苯二甲酸酐与环氧氯丙烷交替共聚

房江华 , 沈之荃

高分子材料科学与工程

研究了Nd(acac)3-Al(i-Bu)3催化剂催化邻苯二甲酸酐(PA)和环氧氯丙烷(ECH)交替共聚合.考察了共聚反应的聚合特征,用红外光谱、核磁共振表征了共聚物结构.共聚反应动力学研究表明共聚反应与单体浓度呈一级关系,与催化剂浓度呈一级关系,表观活化能为112.0 kJ/mol.

关键词: 稀土络合催化剂 , 邻苯二甲酸酐 , 环氧氯丙烷 , 交替共聚

二正丁基锡二(邻氯苯甲酸)酯配合物{[n-Bu2Sn(O2CC6H4C1)]2O}2的微波固相合成、结构及体外抗癌活性

张复兴 , 王剑秋 , 邝代治 , 冯泳兰 , 许志锋 , 庾江喜

应用化学 doi:10.3724/SP.J.1095.2012.00300

二正丁基氧化锡和邻氯苯甲酸按物质的量比1∶2,通过微波固相合成法合成了二正丁基锡邻氯苯甲酸酯配合物{[n-Bu2Sn(O2CC6H4Cl)]2O}2.经X射线衍射方法测定了其晶体结构,配合物属三斜晶系,空间群为P(1),晶体学参数a=1.17653(4) nm,b=1.20672(4) nm,c=2.74090 (9) nm,α=80.493 (2)°,β=83.995 (2)°,γ=64.260(2)°,V=3.4547(2)nm3,Z=2,D(ε)=1.525 g/cm3,μ(MoKα)=16.34 cm-1,F(000)=1592,R1=0.0414,wR2=0.1349.晶体中每一个结构单元包含了2个键参数完全不同的以Sn2O2构成的平面四元环为中心环的二聚体结构分子,锡原子均为五配位的畸变三角双锥构型.对其结构进行量子化学从头计算,探讨了配合物的稳定性、分子轨道能量以及部分前沿分子轨道的组成特征.

关键词: 微波固相合成 , 二正丁基锡邻氯苯甲酸酯 , 晶体结构 , 从头计算

Effects of Homo-bu®er Layer on Properties of Sputter-deposited ZnO Films

Jian Huang

材料科学技术（英文）

Two-step growth regimes were applied to realize a homoepitaxial growth of ZnO films on freestanding diamond substrates by radio-frequency (RF) reactive magnetron sputtering method. ZnO buffer layers were deposited on freestanding diamond substrates at a low sputtering power of 50 W, and then ZnO main layers were prepared
on this buffer layer at a high sputtering power of 150 W. For comparison, a sample was also deposited directly on freestanding diamond substrate at a power of 150 W. The effects of ZnO buffer layers on the structural, optical, electrical and morphological properties of the ZnO main layer were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, semiconductor characterization system and atomic force microscopy (AFM) respectively. The experimental results suggested that homo-buffer layer was helpful to improve the crystalline quality of ZnO/diamond heteroepitaxial films.

关键词: Freestanding diamond

聚合物载体负载TiCl4/i-Bu3Al催化烯烃聚合

周光远 , 黄葆同 , 金国新

应用化学 doi:10.3969/j.issn.1000-0518.2001.02.010

探讨了聚合物负载烯烃聚合催化剂的合成及用于聚合的研究.研究了聚合物作为载体的催化行为.并通过IR，DsC，元素分析和粘度法测定分子量等手段对催化剂及聚合物进行了表征.包括合成聚合物负载的Ti体系催化剂和用所合成的催化剂进行乙烯聚合，乙烯、丙烯与丁二烯共聚合的研究.

关键词: 聚合物负载催化剂 , 烯烃聚合

Enhancing strength and ductility of Mg-12Gd-3Y-0.5Zr alloy by forming a bi-ultrafine microstructure

Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing

By means of equal channel angular pressing (ECAP) technique, an Mg-12Gd-3Y-0.5Zr alloy was processed at 300 degrees C for one and four passes. A bi-ultrafine (BU) microstructure of Mg-alloy, consisting of matrix grains and the second-phase particles with sizes smaller than 1 mu m, was obtained after the fourth pass of ECAP. The formation of this BU microstructure originated from the complex interactions between the matrix grains and second-phase particles during the ECAP processing at elevated temperature. A simultaneous improvement of both strength and ductility was achieved in the sample with the BU microstructure, compared with the original sample. The increase in strength is resulted from the refinement of both matrix grains and second-phase particles, while the improved ductility is attributed to the considerable plasticity provided by both dislocation mechanism and profuse shear bands in the BU microstructure. An enhanced plasticity induced by the shear-band mechanism is proposed for the magnesium alloy with the BU microstructure. (C) 2011 Elsevier B.V. All rights reserved.

关键词: Mg alloy;Equal channel angular pressing (ECAP);Strength;Ductility;Shear bands;Second-phase particles;severe plastic-deformation;high-pressure torsion;cu-al alloys;grain-refinement;mechanical-properties;magnesium alloys;nanostructured metal;tensile;strain;shear