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101.
J. Y. Lee J. H. Chang M. Yang H. S. Ahn S. N. Yi K. Goto K. Godo H. Makino M. W. Cho T. Yao J. S. Song 《Current Applied Physics》2004,4(6):611-614
Luminescence properties of CdTe/ZnSe fractional monolayer grown by atomic layer epitaxy have been investigated. To investigate the origin of the highly efficient luminescence, various optical spectroscopic methods such as, photoluminescence (PL), temporal/spatial resolved PL, temperature dependence PL, and excitation power dependence PL have been used. It is found that structural inhomogeneities affect dominant influence on the line width and line shape of luminescence. The luminescence intensity greatly enhanced by the localization of exciton at the disorder induced localized states. 相似文献
102.
A. Al-Badawi 《International Journal of Theoretical Physics》2007,46(6):1466-1470
We have obtained the exact solution of the equations of motion of a test particle near a thick domain walls. From the solution
it has been shown that the domain walls have repulsive gravitational fields. 相似文献
103.
Abdol R. Hajipour Shadpour E. Mallakpour Iraj Mohammadpoor-Baltork Hadi Adibi 《Monatshefte für Chemie / Chemical Monthly》2003,134(1):45-49
Summary. Benzyltriphenylphosphonium peroxymonosulfate in the presence of catalytic amounts of bismuth chloride was found to be an
efficient and mild reagent for the oxidative cleavage of oximes and semicarbazones to the corresponding carbonyl compounds
under microwave irradiation.
Corresponding author. E-mail: haji@cc.iut.ac.ir
Received March 4, 2002; accepted (revised) April 8, 2002 相似文献
104.
在多项选择题测验分数等于真实分数和猜测分数之和的假设模型下,本文得到了一个多项选择题测验信度的理论公式,并由此给出了测验信度的估计方法。最后,通过两个例子,说明了本文提出的方法在测验信度分析中的应用,并将这种方法与教育测量中常用的库德——理查逊方法(Kuder-Richardson)进行了比较 相似文献
105.
106.
Ivan Horvath Viera Luptakova 《Journal of inclusion phenomena and macrocyclic chemistry》1991,11(3):257-265
Benzothiazolium compounds exhibit pronounced antimicrobial activities and stimulation effects on plant growth. When applied to fields they can pollute soil colloids. In contact with the soil they can potentially interact with a clay fraction giving rise to clay organocomplexes. Model intercalation complexes were prepared using monoionic montmorillonite and a variety of water-soluble benzothia zolium salts. It was found that the adsorption into the silicate interlayer space proceeds via a cation exchange process. Substantial differences were observed in the extent of the reaction between non-substituted andN-substituted species. The sulphur atoms present in the benzothiazolium molecules repel the surface oxygen atom: this is considered to be the factor responsible for prevention of insertion of the guest cations perpendicular to the layers. 相似文献
107.
108.
109.
本文考察了自体移植静脉的纵向应力应变关系。将狗股静脉移植于股动脉,在术后不同时间切取移植静脉进行纵向单轴拉伸实验。结果表明,移植静脉的应力-应变曲线比正常静脉靠近应力坐标轴并在术后逐渐向左移动。这显示了移植血管管壁组织在术后的逐渐硬化。 相似文献
110.
Meng F. Q. Lu M. K. Yang Z. H. Zeng H. 《Journal of Thermal Analysis and Calorimetry》1998,52(2):609-613
The thermal behavior of two new non-linear optical (NLO) materials, urea-(D) tartaric acid (UDT) and urea-(DL) tartaric acid
(UDLT) were studied by using DSC, TG and TMA. The results show that: 1) The two crystals have different melting points but
similar decomposition temperatures due to the influences of intermolecular forces, which is attributed to the stereo effects
of (D)-tartaric and (DL)-tartaric acid molecules; 2) There was only thermal expansion and no thermal contraction when the
UDT and UDLT crystals were heated; 3) There was no phase transition within the measured temperature range; 4) The thermal
expansion of the UDT and UDLT crystals shows a small anisotropy; 5) The specific heats of UDT and UDLT change linearly with
temperature in the measured temperature range and the value for UDT is 1.321 J g-1 K-1 at 320 K while the specific heat of
UDLT is 1.357 J g-1 K-1 at the same temperature.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献