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本文研究了马来酸氢十六酯(HHM)在以甲苯为溶剂的过饱和溶液中的成核过程.测定了以诱导时间表示的成核速率.用经典的成核理论计算了固-液表面张力、成核自由能和临界成核半径.指出HHM晶体在甲苯为溶剂的过饱和溶液中的成核速率随着温度和过饱和比的提高而增大.溶剂的性质也将改变成核速率的大小.  相似文献   

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软X射线分光晶体琥珀酸十八酯的生长研究   总被引:1,自引:1,他引:0  
本文合成了软X射线分光晶体材料琥珀酸十八酯(OSO),对其样品进行了表征和鉴定.对OSO在多种有机溶剂中的结晶性能进行了研究,结果表明在实验的几种有机溶剂中OSO的成核趋势很强,在甲苯和苯中具有较好的结晶特性.测定了OSO在苯和甲苯中的溶解度曲线,并用溶液降温法进行了晶体生长的实验.  相似文献   

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本文根据晶体结构数据,应用周期键链理论,分析了标题化合物的晶体形貌及生长习性,并应用原子-原子势能函数方法,用turbo c编程计算了各显露面的晶面接触能.结果表明,晶体中属于F面的单形有{001};属于S面的单形有{010},{100},{110}.由晶面接触能的大小可知该晶体成薄板状.理论分析与实际情况符合的较好.  相似文献   

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软X射线分光晶体琥珀酸氢十八酯(OHS)的研究   总被引:1,自引:4,他引:1  
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本文介绍了软X射线分光晶体的应用及研究重要性,以及从X射线分光晶体的组成、结构与性能的关系介绍了分光晶体的分类,并对近代晶体生长的方法作了简要的描述。  相似文献   

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本文合成了软X射线分光晶体琥珀酸氢十四酯(THS).通过红外光谱、差示量热扫描等手段对所合成样品进行表征和鉴定.对THS在苯、甲苯、二甲苯、异丙醇等溶剂中的自发成核和结晶形态进行了研究,结果表明THS在苯、甲苯和二甲苯中表现出良好的结晶习性.采用平衡法测定了THS在苯、甲苯和二甲苯中的溶解度曲线.综合考虑结晶习性和溶解度情况,可选择甲苯作为晶体生长的溶剂进行单晶生长实验.  相似文献   

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马来酸氢十八酯晶体生长   总被引:10,自引:6,他引:4  
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本文采用液相法合成了高纯度磺基水杨酸锶(简称SSS)多晶粉末原料,并采用热分析、红外光谱和XRD分析对多晶粉末原料进行表征。以水为溶剂分别在不同pH值下(pH=2.50、1.50和0.60)进行了SSS结晶习性实验。结果表明,在水溶液中当pH=0.60时SSS结晶性最好,实验还测定了SSS晶体在不同pH值溶液中的溶解度曲线,并进行了过饱和溶液成核机理的研究。研究结果表明,当生长溶液pH为0.60时,控制单晶生长温度在40~50℃区间,采用水溶液降温法可生长出63 mm×25 mm×3 mm的透明单晶。  相似文献   

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Crystallography Reports - The title compound 6-phenyl-4-(p-tolyl)pyridin-2(1H)-one was synthesized via one-pot, three component reaction of (E)-1-phenyl-3-(p-tolyl)-2-propen-1-one, ethyl...  相似文献   

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The complex of [CU(CH3CHCOO)2(OPph)]2 has been synthesized and its X-ray crystal structure determined at room temperature, M = 975.96, tetragonal, space group: 141/a(#88), Dx = 1.39 g/ cm3, The final R is 0.067 for 2087 independent observed reflections with 1 > 3α(I). The molecule has an inversion center on the middle of the Cu Cu axis. The bond-length of the Cu Cu is 2.61/(2) Å. The coordinate polyhedron of Cu corresponds to a tetragonal bipyramid. The angle of Cu O P is significantly smaller than that of its adducts [Cu(O2CR)2L]2.  相似文献   

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电光晶体硒酸氢铷(RHSe)的生长动力学   总被引:1,自引:1,他引:0  
本文采用动态循环观察法测量了RHSe晶体在水溶液中不同过饱和度下主要显露晶面的生长速率.结果表明,RHSe晶体主要显露晶面的生长机制是多二维成核生长机制,在饱和点为38.00℃的溶液中,RHSe晶体的{111}和{101}晶面的临界过饱和度分别为1.01;和1.16;.实验过程中还发现,当过饱和度大于1.76;时,晶体生长速率太快而出现宏观缺陷,因而在生长RHSe单晶时,过饱和度应控制在1.76;以下.  相似文献   

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NdxY1-xAl3(BO3)4 (NYAB) single crystal was grown by the flux method using K2CO3 MoO3 as a solvent. By x-ray projection topography, the defects on a (0001) slice of the NYAB crystal are investigated. It is found that the main grown-in defects in NYAB crystal are growth bands, growth sector boundaries and inclusions. The formation of defects is discussed and methods to reduce the defects are proposed.  相似文献   

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Abstract  Bis(isothiocyanato)-bis(pyridine) zinc(II) crystal has been prepared at room temperature and characterized by elemental analysis, IR spectrum and X-ray single crystal determination. The complex crystallizes in monoclinic space group P21/m with unit cell parameters: a = 5.5786(3), b = 11.0587(5), c = 12.1616(6) ?, β = 96.776(3)°, V = 745.03(6) ?3, Z = 2, D = 1.514 g cm−3. The X-ray structure determination has revealed that the crystal is centered-symmetrical and the crystallographic symmetry face runs the two isothiocyanate ligands and the Zn(II) cation. Index Abstract  The title compound, bis(isothiocyanato)-bis(pyridine) zinc(II), was synthesized by zinc compound, KSCN and C5H5N (pyridine) and its crystal structure was determined. Single crystal X-ray structure determination reveals that the crystal is centered-symmetrical, and the crystallographic symmetry face runs the two isothiocyanate ligands and the Zn(II) cation.   相似文献   

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The title compound [(C10H26N4)·Cu+2·H2O]·SO 4 –2 ·3H2O[A] has been studied by X-ray diffraction and IR spectroscopy. It crystalized in monoclinic system, in space group P 2l/c, with cell dimensions ofa=8.128(2),b=15.472(2),c=15.350(2) Å, =102.66(2)°. The copper atom is five coordinated with four nitrogen atoms and one axial water molecule forming tricyclic chelated spermine complex. The chelated complex consists of two six-membered and one sevenmembered rings. The seven membered ring is disordered. The amine groups from spermine molecule are hydrogen bonded to the sulphate anion and the water molecule. All water molecules form an infinitive hydrogen bonding network utilizing sulphate anions as bridges. The IR analysis before and after dehydration of [A] agree with the X-ray results.  相似文献   

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本文介绍了X射线测量单晶应力的原理和方法,测量了Si单晶的应力,比较了双晶摇摆和三轴晶ω~2θ扫描对结果的影响,考察了计算过程中数据组个数,无应力布拉格角θ_0对应力测量的影响.结果表明,采用三轴晶ω~2θ扫描比双晶摇摆更准确,多重线性回归方法对θ_0依赖性很小,但测量数据组个数不应低于6.  相似文献   

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