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51.
Qiuhua Nie Guoxiang Wang Xunsi Wang Mohamed Barj Tiefeng Xu Shixun Dai Jong Heo 《Journal of Non》2011,357(11-13):2362-2365
A systematic series of (100 ? x)(GeTe4.3) ? xCdI2/ZnI2 far infrared transmitting glasses were prepared by traditional melt-quenching method. ZnI2 (20 mol%) can be introduced in the glassy matrix, while only 10 mol% CdI2 can be incorporated in the Ge-Te-CdI2 glass system. Based on differential thermal analysis (DTA) data, most of the glass samples have good thermal stability. A maximum ΔT value of 115 °C was obtained for the glass composition 90(GeTe4.3)–10ZnI2. The allowed indirect transition optical band gap was calculated according to the classical Tauc equation. It is found that the indirect optical band gap decreased from 0.619 to 0.569 eV with the CdI2 addition and increased from 0.628 to 0.677 eV with the ZnI2 addition. According to infrared transmission spectra, the Ge-Te-CdI2/ZnI2 glasses show wide IR transparency. 相似文献
52.
Yaryong Heo 《Journal of Mathematical Analysis and Applications》2009,351(1):152-162
For and m>0 we consider the maximal operator given by
53.
Lim JM Moon JH Yi GR Heo CJ Yang SM 《Langmuir : the ACS journal of surfaces and colloids》2006,22(8):3445-3449
Electrospun nanofibers were used as confining geometries for fabricating 1-D colloidal assemblies. Silica particles dispersed in several different polymer solutions were cast into nanofibers by an electrospinning process. The silica particle configurations were examined in terms of the size ratio of silica particles to nanofibers and the properties of the dispersing medium. As the electrospun fiber was extended highly, the silica particles dispersed in the polymer solution began to assemble spontaneously into a pearl-necklace structure. We also demonstrated the alignment of 1-D silica assemblies using a designed configuration of collector electrodes. 相似文献
54.
Min-Sung Kang Chang-Ho Hong Jino Heo Jong-In Lim Hyung-Jin Yang 《International Journal of Theoretical Physics》2014,53(6):1862-1866
This comment explains that the quantum signature scheme proposed by Ming-Xing Luo et al. (in Int. J. Theor. Phys. 51:2134, 2012) cannot satisfy the signature requirements. The comment presents methods of possible attacks by forgers, while also demonstrating that it is difficult to proceed by the normal protocol because of some errors in the formula of the scheme. 相似文献
55.
Heo J Lim CK Whang DR Shin J Jeong SY Park SY Kwon IC Kim S 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(28):8699-8704
Colorless 1,3-bis(dicyanomethylidene)indan is an organic acid (pK(a) ≈3.0) that turns blue in polar media owing to self-deprotonation. Moreover, its colored conjugate base shows potential as a minimal anionic polymethine dye for probing biomolecules in cells and in vivo through noncovalent complexation and near-infrared fluorescence signaling. 相似文献
56.
Choi CM Choi DH Heo J Kim NJ Kim SK 《Angewandte Chemie (International ed. in English)》2012,51(29):7297-7300
Conformation selective: A new technique of ultraviolet-ultraviolet hole burning spectroscopy that can be applied to ions stored in a quadrupole ion trap (QIT) is developed and used to obtain the conformation-selective electronic spectra of dibenzo[18]crown-6 complexes with alkali metal cations (M(+), see picture; F(+) = fragment). 相似文献
57.
D. Gopi R. Saraswathy G. Athithya L. Kavitha Jeong‐Heo Bae Dae–Kyeong Kim 《Surface and interface analysis : SIA》2012,44(10):1331-1337
In this paper, we have reported the anti‐corrosion performance of ceria / poly (indole‐co‐pyrrole) (Ce/(poly(In‐co‐Py)) bilayer coating on low nickel stainless steel (LN SS). Electrochemical polymerization of (poly (In‐co‐Py)) was achieved on ceria‐coated LN SS (CeO2/LN SS) in acetonitrile medium containing LiClO4 (ACN‐LiClO4) by cyclic voltammetric technique. The coatings were characterized by analytical techniques like Fourier transform infrared spectroscopy, scanning electron microscopy with energy dispersive analysis of X‐ray, respectively. The mechanical behavior of the coatings was studied using peel test, hardness and wear resistance tests. The corrosion defensive performance of this bilayer coating on LN SS was investigated using electrochemical techniques such as potentiodynamic polarization and electrochemical impedance spectroscopy in 0.5 M H2SO4. These results show that the bilayer coating on LN SS lowered the permeability of corrosive ions present in the acidic medium and thus acts as a barrier against the attack of corrosive environment. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Park KM Whang D Lee E Heo J Kim K 《Chemistry (Weinheim an der Bergstrasse, Germany)》2002,8(2):498-508
This paper reports a synthetic strategy to construct one- and two-dimensional (1D and 2D) polyrotaxanes, in which a number of rings are threaded onto a coordination polymer, by the combination of self-assembly and coordination chemistry. Our approach to construct polyrotaxanes with high structural regularity involves threading a cucurbituril (CB) "bead" with a short "string" to form a stable pseudorotaxane, followed by linking the pseudorotaxanes with metal ions as "linkers" to organize into a 1D or 2D polyrotaxane. A 4- or 3-pyridylmethyl group is attached to each end of 1,4-diaminobutane or 1,5-diaminopentane to produce the short "strings", which then react with the cucurbituril "bead" to form stable pseudorotaxanes. The reaction of the pseudorotaxanes with various transition metal ions including CuII, CoII, NiII, AgI, and CdII produces 1D or 2D polyrotaxanes, in which many molecular "beads" are threaded onto 1D or 2D coordination polymers as confirmed by X-ray crystallography. The overall structure of a polyrotaxane is the result of interplay among various factors that include the coordination preferences of the metal ion, spatial disposition of the donor atoms with respect to the CB beads in the pseudorotaxane, and the size and coordination ability of the counteranion. 相似文献