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921.
922.
C. B. Moon C. S. Lee S. J. Chae J. H. Ha J. C. Kim T. Komatsubara T. Hayakawa J. Lu M. Matsuda T. Watanabe K. Furuno 《Zeitschrift für Physik A Hadrons and Nuclei》1997,357(1):53-59
High-spin states of the 115Te were studied by in-beam spectroscopy with the 89Y (29Si, p2n) fusion-evaporation reaction at a beam energy of 108 MeV. γ?γ coincidence and γ?γ angular correlation analyses were employed for determining the level scheme of 115Te. We have identified two vibrational-like bands built on the νh11/2 and νg7/2 quasiparticle states and the noncollective oblate states from the full alignment of quasiparticle configurations. In addition, a regular ΔI = 2 sequence with positive-parity was found for the first time in odd-A Te nuclei. This sequence is interpreted as a deformed structure resulting from three-quasiparticle alignment having the [π(g7/2, h 11/2) ? ν(h 11/2)] configuration. Calculations of total Routhian surfaces and cranked shell model were performed and were used for assigning quasiparticle configurations to the states in 115Te. 相似文献
923.
Yong‐Jin Choi Seung‐Hyeon Moon Takeo Yamaguchi Shin‐Ichi Nakao 《Journal of polymer science. Part A, Polymer chemistry》2003,41(9):1216-1224
Morphological control of membranes with plasma graft‐filling polymerization was proposed for thick, porous membranes. The morphology depended closely on the plasma within the membrane pore, which was determined by the plasma‐discharge power (PDP) and the gas pressure. The membrane morphology was investigated in terms of solvent composition in monomer solution, PDP, Ar pressure, and pore size of a substrate. Morphologies of membranes prepared were evaluated by a microscopic Fourier transform infrared mapping method. This study demonstrates that it is possible to control the membrane morphology by manipulating the plasma power and Ar pressure instead of morphological control by solvent‐dependent monomer activity. Additionally, through indirect methods this study reveals that plasma exists even in sub‐micropores (ca. 0.4 μm in diameter). © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1216–1224, 2003 相似文献
924.
Moon Suk Kim Kwang Su Seo Gilson Khang Sun Hang Cho Hai Bang Lee 《Journal of polymer science. Part A, Polymer chemistry》2004,42(22):5784-5793
Diblock copolymers consisting of methoxy poly(ethylene glycol) (MPEG) and poly(?‐caprolactone) (PCL), poly(δ‐valerolactone) (PVL), poly(L ‐lactic acid) (PLLA), or poly(lactic‐co‐glycolic acid) (PLGA) as biodegradable polyesters were prepared to examine the phase transition of diblock copolymer solutions. MPEG–PCL and MPEG–PVL diblock copolymers and MPEG–PLLA and MPEG–PLGA diblock copolymers were synthesized by the ring‐opening polymerization of ?‐caprolactone or δ‐valerolactone in the presence of HCl · Et2O as a monomer activator at room temperature and by the ring‐opening polymerization of L ‐lactide or a mixture of L ‐lactide and glycolide in the presence of stannous octoate at 130 °C, respectively. The synthesized diblock copolymers were characterized with 1H NMR, IR, and gel permeation chromatography. The phase transitions for diblock copolymer aqueous solutions of various concentrations were explored according to the temperature variation. The diblock copolymer solutions exhibited the phase transition from gel to sol with increasing temperature. As the polyester block length of the diblock copolymers increased, the gel‐to‐sol transition moved to a lower concentration region. The gel‐to‐sol transition showed a dependence on the length of the polyester block segment. According to X‐ray diffraction and differential scanning calorimetry thermal studies, the gel‐to‐sol transition of the diblock copolymer solutions depended on their degrees of crystallinity because water could easily diffuse into amorphous polymers in comparison with polymers with a crystalline structure. The crystallinity markedly depended on both the distinct character and composition of the block segment. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5784–5793, 2004 相似文献
925.
Eun Ha Choi Jeong Chull Ahn Min Wook Moon Jin Goo Kim Myung Chul Choi Choon Gon Ryu Sung Hyuk Choi Tae Seung Cho Yoon Jung Guang Sup Cho Han Sup Uhm 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》2002,30(6):2160-2164
The electron temperature and plasma density at the lateral distance of 125 /spl mu/m from the center of sustaining electrode gap have been investigated by a Langmuir probe along with the high-speed discharge image in coplanar alternating current plasma display panels. The plasma density at the lateral distance of 125 /spl mu/m from the center of sustaining electrode gap is shown to be maximum value of 3.7/spl times/10/sup 11/ cm/sup -3/, whereas the electron temperature is measured to be decreased from 1.8 to 0.8 eV as the gas pressure increases from 150 to 400 torr in this experiment. It is noted that the electron temperatures measured by the Langmuir probe and high-speed image camera are in good agreement with each other within 5% error limit. 相似文献
926.
We investigate the structure and the formation energy of the pentagon–heptagon pairs (5775) defects of BN nanotubes using a molecular-mechanics method. For (n, 0) BN nanotubes, the homoelemental bonds of the 5775 defect may be located nearly either parallel or perpendicularly in the direction of tube axis. The former is energetically favored and strongly affects the reduction of the strain with decreasing radius. The formation energy of the 5775 defect, which increases with increasing radius, is lower than that of the tetragon–octagon pairs (4884). The 5775 defect of BN nanotubes is structurally and energetically stable, as compared to the 4884 defect. 相似文献
927.
Time-of-flight (TOF) mass spectra for a peptide (Y6) were obtained by utilizing matrix-assisted infrared laser desorption ionization (IR-MALDI) with glycerol as the matrix and
by ultraviolet MALDI with α-cyano-4-hydroxycinnamic acid (CHCA), sinapinic acid (SA), and 2,5-dihydroxybenzoic acid (DHB).
Collisional activation during ion extraction and exothermicity in the gas-phase proton transfer were found to be unimportant
as the driving forces for in-source (ISD) and post-source (PSD) decays, indicating that the thermal energy acquired during
photo-ablation is responsible for their occurrence. The temperatures of [Y6 + H]+ in the ‘early’ and ‘late’ matrix plumes were estimated by the kinetic analysis of the ISD and PSD yields, respectively. The
order of the temperatures was glycerol < DHB ≈ SA < CHCA in the early plume and glycerol < DHB < SA < CHCA in the late plume.
For each matrix, the temperature in the late plume was lower than in the early plume by 300–400 K, which was attributed to
expansion cooling. The model (thermalization followed by expansion cooling) proposed to explain the occurrence of both rapid
ISD and slow PSD is not only in sharp contrast with but also mutually exclusive with the prevailing explanation that the exothermicity
in proton transfer and in-plume collisional activation are the driving forces for ion fragmentation in MALDI. The model also
explains why MALDI is more successful for mass spectrometry of labile molecules than other desorption techniques that do not
utilize a matrix. Factors affecting the plume temperature are also discussed. 相似文献
928.
We observed how combined mechanical stimuli affect the proliferation and differentiation of pre-osteoblasts. For this research, a bioreactor system was developed that can simultaneously stimulate cells with cyclic strain and ultrasound, each of which is known to effectively stimulate bone tissue regeneration. MC3T3-E1 pre-osteoblasts were chosen for bone tissue engineering due to their osteoblast-like characteristics. 3-D scaffolds were fabricated with polycaprolactone and poly-L-lactic acid using the salt leaching method. The cells were stimulated by the bioreactor with cyclic strain and ultrasound. The bioreactor was set at a frequency of 1.0 Hz and 10 % strain for cyclic strain and 1.0 MHz and 30 mW/cm(2) for ultrasound. Three experimental groups (ultrasound, cyclic strain, and combined stimulation) and a control group were examined. Each group was stimulated for 20 min/day. Mechanical stimuli did not affect MC3T3-E1 cell proliferation significantly up to 10 days when measured with the cell counting kit-8. However, gene expression analysis of collagen type-I, osteocalcin, RUNX2, and osterix revealed that the combined mechanical stimulation accelerated the matrix maturation of MC3T3-E1 cells. These results indicate that the combined mechanical stimulation can enhance the differentiation of pre-osteoblasts more efficiently than simple stimuli, in spite of no effect on cell proliferation. 相似文献
929.
Shin SM Moon D Jeong KS Kim J Thallapally PK Jeong N 《Chemical communications (Cambridge, England)》2011,47(33):9402-9404
The chiral 3D MOFs resulted from the packing of chiral 1D SBBs were studied. It was demonstrated that the final packing pattern is sensitively dependent on the dimension of SBBs. In addition, we were able to identify a new plywood-like network from ligand 2H(2) exhibiting an unprecedented six-way chiral helical packing motif, which extends the list of invariant rod packings. 相似文献
930.
Lee WJ Lee DH Han TH Lee SH Moon HS Lee JA Kim SO 《Chemical communications (Cambridge, England)》2011,47(1):535-537
Biomimetic mineralization of vertical N-doped carbon nanotubes is demonstrated as a straightforward route for carbon-based mineral nanocomposites. The N-doped sites along the carbon nanotube backbone play the role of nucleation sites for mineralization. 相似文献