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1.
以[(bpca)Fe(CN)3]-(bpca=二(2-吡啶羰基)酰胺阴离子)为构筑基元,设计合成了2个新颖的3d-4f异金属配合物,{[(bpca)Fe(CN)3Pr(H2O)5]Cl2}n(1)和{[(bpca)2Fe2(CN)6Pr(H2O)6]Cl·4H2O}n(2),并测定了它们的晶体结构.化合物1的晶体属正交晶系,Pnma空间群;而化合物2属三斜晶系,P1空间群.在这2个化合物中,[(bpca)Fe(CN)3]-和[Pr(H2O)x]3 (1,x=5;2,x=6)交替排列形成一维链状结构,并通过π-π堆积作用、氢键作用及分子间短距离相互作用形成三维网络结构. 相似文献
2.
Effect of annealing on structural, optical and electrical properties of ZnS/porous silicon composites 下载免费PDF全文
ZnS films were prepared by pulsed laser deposition (PLD) on
porous silicon (PS) substrates. This paper investigates the effect
of annealing temperature on the structural, morphological, optical
and electrical properties of ZnS/PS composites by x-ray diffraction
(XRD), scanning electron microscope (SEM), photoluminescence (PL)
and I--V characteristics. It is found that the ZnS films deposited
on PS substrates were grown in preferred orientation along
β-ZnS (111) direction, and the intensity of diffraction peak
increases with increasing annealing temperature, which is attributed
to the grain growth and the enhancement of crystallinity of ZnS
films. The smooth and uniform surface of the as-prepared ZnS/PS
composite becomes rougher through annealing treatment, which is
related to grain growth at the higher annealing temperature. With
the increase of annealing temperature, the intensity of
self-activated luminescence of ZnS increases, while the luminescence
intensity of PS decreases, and a new green emission located around
550~nm appeared in the PL spectra of ZnS/PS composites which is
ascribed to the defect-center luminescence of ZnS. The I--V
characteristics of ZnS/PS heterojunctions exhibited rectifying
behavior, and the forward current increases with increasing
annealing temperature. 相似文献
3.
Effects of Substrate Temperature and Nitrogen Pressure on Growth of AIN Films by Pulsed Laser Deposition 下载免费PDF全文
Highly oriented aluminium nitride (AIN) films are grown on p-Si (100) substrates by pulsed laser deposition, and their characteristics of structure and composition are studied by x-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. The results show that the deposited films exhibit good crystalline properties with a sharp x-ray diffraction peak at 2θ= 33.15 ° corresponding to AIN h (100) crystalline orientation. The influences of substrate temperature and ambient nitrogen (N2) pressure on the crystallinity of A1N films are remarkable. At room temperature, when the ambient N2 pressure arises from 5 × 10^-6 Pa to 5 Pa, the crystallinity of the film becomes better. When the substrate temperature is 600℃, the film has the best crystallinity at 0.05 Pa. Furthermore, the effects of substrate temperature and ambient N2 pressure on the combination of A1-N bonds and surface morphology of AIN films are also studied. 相似文献
4.
合成了4-硝基邻苯二硫酚配体及相应金属镍配合物,(Bu4N)2[Ni(nbdt)2]
(1)和(Bu4N)[Ni(nbdt)2] (2)(nbdt=4-硝基邻苯二硫酚阴离子), 并通过X-射线单晶结构测定、循环伏安、ESR谱、紫外可见吸收光谱和变温磁化率实验对其结构和性质进行了表征。这两个化合物均为略有变形的平面四方型配合物。配合物2是由配合物1通过I2氧化制备。配合物2含有一个未成对电子,磁性研究表明由于分子间的自旋耦合使它表现为反铁磁性。 相似文献
5.
本文以一种水溶性的冠醚环化四硫富瓦烯羧酸为配体,成功合成并表征了结构新颖的含四硫富瓦烯衍生物的二价钴一维配位聚合物[{Co2(trioTTF)2(H2O)6}·5H2O]n(1).X射线单晶衍射结构分析表明,在配位聚合物1中Co^2+离子之间通过羧酸桥联形成一维链状结构,相邻链的四硫富瓦烯羧酸配体之间存在较短的S…S相互作用.尽管配位聚合物1的室温电导率很小,但其电阻-温度特性曲线显示具有半导体性质.同时,磁性研究表明,低温下由羧酸桥联的Co2+离子存在弱的铁磁相互作用.本研究为分子磁性半导体的进一步设计合成提供了思路. 相似文献
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7.
Lattice Boltzmann simulation of behaviour of particles moving in blood vessels under the rolling massage 下载免费PDF全文
The rolling massage is one of the most important manipulations in Chinese massage,which is expected to eliminate many diseases.Here,the effect of the rolling massage on a pair of particles moving in blood vessels under rolling massage manipulation is studied by the lattice Boltzmann simulation.The simulated results show that the motion of each particle is considerably modified by the rolling massage,and it depends on the relative rolling velocity,the rolling depth,and the distance between particle position and rolling position.Both particles’ translational average velocities increase almost linearly as the rolling velocity increases,and obey the same law.The increment of the average relative angular velocity for the leading particle is smaller than that of the trailing one.The result is helpful for understanding the mechanism of the massage and to further develop the rolling techniques. 相似文献
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9.
Study of white light emission from ZnS/PS composite system 总被引:1,自引:0,他引:1
ZnS films were deposited by pulsed laser deposition(PLD)on porous silicon(PS)substrates formed by electrochemical anodization of p-type(100)silicon wafer.The photoluminescence(PL)spectra of ZnS/PS composites were measured at room temperature.Under different excitation wavelengths,the relative integrated intensities of the red light emission from PS layers and the blue-green emission from ZnS films had different values.After samples were annealed in vacuum at different temperatures(200,300,and 400℃)for 30 min respectively,a new green emission located at around 550 nm appeared in the PL spectra of all ZnS/PS samples,and all of the ZnS/PS composites had a broad PL band(450-700 nm)in the visible region,exhibiting intensively white light emission. 相似文献
10.
ZnS thin films are deposited on porous silicon (PS) substrates with different porosities by pulsed laser deposition (PLD). The photoluminescence (PL) spectra of the samples are measured at room temperature. The results show that the PL intensity of PS after deposition of ZnS increases and is associated with a blue shift. With the increase of PS porosity, a green emission at about 550 nm is observed in the PL spectra of ZnS/PS systems, which may be ascribed to the defect-center luminescence of ZnS films. Junction current- voltage (I-V) characteristics were studied. The rectifying behavior of I-V characteristics indicates the formation of ZnS/PS heterojunctions, and the forward current is seen to increase when the PS porosity is increased. 相似文献