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1.
Thi Thi Nge Naruhito Hori Akio Takemura Hirokuni Ono Tsunehisa Kimura 《Journal of Polymer Science.Polymer Physics》2003,41(7):711-714
A high magnetic field of 5 T was used to fabricate a magnetically aligned, optically anisotropic, liquid‐crystalline chitin/poly(acrylic acid) composite. The aligned mesophase was fixed by photoinitiated free‐radical polymerization. From an examination of polarized optical micrographs and an X‐ray diffraction study, a high degree of orientation of 0.70 was observed for the composite with a higher liquid‐crystalline chitin concentration (10.70 wt %); the orientation was reduced with a decreased chitin concentration at a given acrylic acid concentration. The X‐ray data for the developed composite showed a uniplanar orientation for the chitin crystallites, with its molecular long axes perpendicular to the direction of the magnetic field. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 711–714, 2003 相似文献
2.
Journal of Global Optimization - Improperly efficient solutions in the sense of Geoffrion in linear fractional vector optimization problems with unbounded constraint sets are studied systematically... 相似文献
3.
Advances in Data Analysis and Classification - Online social network is a major media for many types of information communication. Although the primary purpose of social networks is to connect... 相似文献
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Alexander I. Popov Alfred J. Smetana Jean-Pierre Kintzinger Thi Thanh-Tam Nguyêen 《Helvetica chimica acta》1980,63(3):668-673
Complexation between crown ethers 12C4, 15C5, 18C6 and cryptand 222, and alkali cations Li+, Na+, K+ in various solvents were studied by 17O-NMR. spectroscopy. Small diamagnetic shifts arising from the cation electric field are observed. They increase according to the sequence K+ < Na+ < Li+. 17O-linewidth are discussed and compared to the 13C relaxation times. Linewidth modification results mainly from modifications of the effective correlation time. In general, for crown ethers, considerable line broadening occurs when the cation fits well into the cavity but line narrowing occurs when the cation is much smaller than the cavity. 相似文献
6.
Clark TD Ferrigno R Tien J Paul KE Whitesides GM 《Journal of the American Chemical Society》2002,124(19):5419-5426
This article presents a strategy for the fabrication of ordered microstructures using concepts of design inspired by molecular self-assembly and template-directed synthesis. The self-assembling components are 4-microm-thick hexagonal metal plates having sides 10 microm in length ("hexagons"), and each template consists of a 4-microm-thick circular metal plate surrounding a central cavity, the perimeter of which is complementary in shape to the external edges of a two-dimensional, close-packed array of hexagons. The hexagons and templates (collectively, "pieces") were fabricated via standard procedures and patterned into hydrophobic and hydrophilic regions using self-assembled monolayers (SAMs). Templated self-assembly occurs in water through capillary interactions between thin films of a nonpolar liquid adhesive coating the hydrophobic faces of the pieces. The hexagons tile the cavities enclosed by the templates, and the boundaries of the cavities determine the sizes and shapes of the assemblies. Curing the adhesive with ultraviolet light furnishes mechanically stable arrays having well-defined morphologies. By allowing control over the structures of the resulting aggregates, this work represents a step toward the development of practical methods for microfabrication based on self-assembly. 相似文献
7.
In this paper the phenomenon of a photosensitive ion complex of Brilliant Yellow and ferric ions formation in the electrolyte phase and its subsequent deposition within a bilayer lipid membrane (BLM) is described. Deposition of light sensitive complex into the BLM considerably increases its mechanical stability and drastically changes its electrochemical and photoelectrical properties as well. 相似文献
8.
S. V. Baryshnikov E. V. Charnaya A. Yu. Milinskii A. Yu. Goikhman C. Tien M. K. Lee L. J. Chang 《Physics of the Solid State》2013,55(5):1070-1073
Variations with temperature of the linear dielectric permittivity and amplitude of the third harmonic were studied for nanoporous MCM-41 matrices with 4.0-nm channel pores filled with the (NH4)2SO4 ferroelectric, in comparison with bulk ammonium sulfate. The measurements were performed upon heating and cooling in the temperature range from 100 K to room temperature. A noticeable shift to low temperatures (by approximately 25 K) for the ferroelectric phase transition in the MCM-41/(NH4)2SO4 nanocomposite as compared to bulk (NH4)2SO4 was revealed. The temperature hysteresis observed at the phase transition in the nanocomposite was approximately 2 K which is close to that in bulk ammonium sulfate. The significant decrease of the transition temperature in nanostructured ammonium sulfate agrees with the theoretical predictions based on the Landau and Ising models of the size effect on the ferroelectric phase transition in isolated small particles. 相似文献
9.
I. E. Smirnova H. Do Thi Thu O. B. Kazakova G. A. Tolstikov O. S. Kukovinets A. N. Lobov K. Yu. Suponitskii 《Russian Journal of Organic Chemistry》2012,48(10):1370-1376
Oxidation of dipterocarpol and its derivatives with ozone gave compounds containing lactone, lactol, alkoxytetrahydrofuran, aldehyde, and methyl ketone fragments in the side chain, as well as 1,2,4-trioxolane fragment in the A ring. The molecular and crystalline structures of dipterocarpol were determined by X-ray analysis. 相似文献
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