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41.
A. Hossain A.E. Bolotnikov G.S. Camarda Y. Cui G. Yang K-H. Kim R. Gul L. Xu R.B. James 《Journal of Crystal Growth》2010,312(11):1795-1799
We explored some unique defects in a batch of cadmium zinc telluride (CdZnTe) crystals, along with dislocations and Te-rich decorated features, revealed by chemical etching. We extensively investigated these distinctive imperfections in the crystals to identify their origin, dimensions, and distribution in the bulk material. We estimated that these features ranged from 50 to 500 μm in diameter, and their depth was about ∼300 μm. The density of these features ranged between 2×102 and 1×103 per cm3. We elaborated a model of them and projected their effect on charge collection and spectral response. In addition, we fabricated detectors with these defective crystals and acquired fine details of charge-transport phenomena over the detectors’ volume using a high-spatial resolution (25 μm) X-ray response mapping technique. We related the results to better understand the defects and their influence on the charge-transport properties of the devices. The role of the defects was identified by correlating their signatures with the findings from our theoretical model and our experimental data. 相似文献
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Nonperturbative corrections from loop quantum cosmology (LQC) to the scalar matter sector are already known to imply inflation. We prove that the LQC modified scalar field generates exponential inflation in the small scale factor regime, for all positive definite potentials, independent of initial conditions and independent of ambiguity parameters. For positive semidefinite potentials it is always possible to choose, without fine-tuning, a value of one of the ambiguity parameters such that exponential inflation results, provided zeros of the potential are approached at most as a power law in the scale factor. In conjunction with the generic occurrence of bounce at small volumes, particle horizon is absent, thus eliminating the horizon problem of the standard big bang model. 相似文献
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Shen M Li G Lu BZ Hossain A Roschangar F Farina V Senanayake CH 《Organic letters》2004,6(22):4129-4132
[reaction: see text] The first practical and economical process for synthesis of 2,3-disubstituted indole compounds has been developed with high regioselectivity by palladium-catalyzed indolization of 2-bromo- or chloroanilines and their derivatives with internal alkynes. 相似文献
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A.K.M. Akther Hossain K. Khirul Kabir T. Kawai 《Journal of Physics and Chemistry of Solids》2007,68(10):1933-1939
Structural, AC and DC magnetic properties of polycrystalline Zn1−xCoxFe2O4 (x=0.2, 0.4) samples sintered at various temperatures (1100-1300 °C), and various dwell times (0.2-15 h) have been investigated thoroughly. The bulk density of the Zn0.60Co0.40Fe2O4 samples increases as the sintering temperature (Ts) increases from 1100 to 1250 °C, and above 1250 °C the bulk density decreases slightly. The Zn0.80Co0.20Fe2O4 samples show similar behavior of changes to that of Zn0.60Co0.40Fe2O4 samples except that the bulk density is found to be highest at 1200 °C. The DC magnetization as a function of temperature curves show that the Zn0.60Co0.40Fe2O4 sample is ferrimagnetic at room temperature while the Zn0.80Co0.20Fe2O4 sample is paramagnetic at room temperature. The Tc of Zn0.80Co0.20Fe2O4 sample is found to be 170 K from DC magnetization measurement. Separate measurement (AC magnetization), initial permeability as a function of temperature shows that the Tc of the Zn0.60Co0.40Fe2O4 sample is 353 K. Slight variation of Tc is observed depending on sintering condition. The initial permeability for the Zn0.60Co0.40Fe2O4 composition sintered at 1250 °C is found to be maximum. 相似文献
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Ann-Sophie Persson Eric Westman Fu-Hua Wang Firoj Hossain Khan Christian Spenger Catharina Lavebratt 《BMC neuroscience》2007,8(1):10
Background
Mutations in the Shaker-like voltage-gated potassium channel Kv1.1 are known to cause episodic ataxia type 1 and temporal lobe epilepsy. Mice that express a malfunctional, truncated Kv1.1 (BALB/cByJ-Kv1.1 mceph/mceph ) show a markedly enlarged hippocampus and ventral cortex in adulthood. 相似文献50.
Kalyanmoy Jana Somnath Das Tithi Maity Maidul Hossain Subhas Chandra Debnath 《Journal of Coordination Chemistry》2018,71(10):1497-1509
A new Co(II) complex of general formula [Co(L)2] has been synthesized from a NNO tridentate Schiff base ligand, 2-[(piperidin-2-ylmethylimino)-methyl]-phenol (L). The title complex is characterized by elemental, spectroscopic, antibacterial, and single crystal X-ray structural studies. X-Ray crystallography reveals that the complex shows a distorted octahedral geometry around the Co(II) ion. The complex was tested against several bacteria and shows good antibacterial activities against almost all of the bacteria. The interactions of the title complex with calf thymus deoxyribonucleic acid (CT-DNA) have been investigated by electronic absorption and fluorescence spectroscopy, showing that the complex interacts with CT-DNA via partial intercalation. Thermogravimetric analysis (TGA) of the complex has also been reported and the result shows that the complex is thermally stable up to 134 °C. 相似文献