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111.
112.
Ruili Zhang Tomonori Maeda Sho Kusaka Kei-ichiro Murai 《Journal of solid state chemistry》2010,183(3):620-623
Host lattice Ba3Si5O13−δNδ oxonitridosilicates have been synthesized by the traditional solid state reaction method. The lattice structure is based on layers of vertex-linked SiO4 tetrahedrons and Ba2+ ions, where each Ba2+ ion is coordinated by eight oxygen atoms forming distorted square antiprisms. Under an excitation wavelength of 365 nm, Ba3Si5O13−δNδ:Eu2+ and Ba3Si5O13−δNδ:Eu2+,Ce3+ show broad emission bands from about 400-620 nm, with maxima at about 480 nm and half-peak width of around 130 nm. The emission intensity is strongly enhanced by co-doping Ce3+ ions into the Ba3Si5O13−δNδ:Eu2+ phosphor, which could be explained by energy transfer. The excitation band from the near UV to the blue light region confirms the possibility that Ba3Si5O13−δNδ:Eu2+, Ce3+ could be used as a phosphor for white LEDs. 相似文献
113.
Mizoshita N Yamanaka K Shimada T Tani T Inagaki S 《Chemical communications (Cambridge, England)》2010,46(48):9235-9237
Polycondensation of 9-mesityl-10-methylacridinium-bridged organosilane in the presence of a nonionic surfactant yielded a mesostructured organosilica solid with a functional framework that exhibited long-lived photoinduced charge separation. 相似文献
114.
A photo-induced radical pair of FADH· and Y8· and in BLUF protein SyPixD was studied by pulsed electron paramagnetic resonance (EPR) spectroscopy. Blue light illumination
at 150 K for 30 min followed by cooling to 50 K during illumination induced the stable radical pair. The EPR signal has been
characterized by a Pake doublet signal with complete S = 1 spin state. The radical pair was utilized as a probe to analyze the oligomer of SyPixD. The relative arrangement of PixD
proteins in the complex was investigated by pulsed electron–electron double resonance (PELDOR) with the orientation selection.
Based on the decameric structure in the crystal, the possible structure for the PELDOR results was discussed. 相似文献
115.
Takeshi Yoshizako Akihiko WadaKoji Uchida Shinji HaraMikio Igawa Hajime KitagakiStephan E. Maier 《Magnetic resonance imaging》2011,29(1):106-110
Purpose
This retrospective study was designed to evaluate the apparent diffusion coefficient (ADC) of line scan diffusion images (LSDI) in normal prostate and prostate cancer. Single-shot echo planner images (SS-EPI) were used for comparison.Materials and Methods
Twenty prostate tumors were examined by conventional MRI in 14 patients prior to radical prostatectomy. All patients were examined with a 1.5-T MR imager (Signa CV/i ver. 9.1 GE Medical System Milwaukee, WI, USA). Diffusion-weighted MR imaging (DWI) using LSDI was performed with a pelvic phased-array coil, with b values of 5 and 800 s/mm2. DWI using SS-EPI was performed with a body coil, with b values of 0 and 800 s/mm2. The ADCs of each sequence for 14 normal prostate and 20 prostate cancers were histopathologically assessed. Signal-to-noise ratio (SNR) on DWI was estimated and compared for each sequence.Results
The mean ADCs (±S.D.) of normal peripheral zones (PZ), transition zones (TZ) and cancer (in 10−3 mm2/s) that used LSDI were 1.42±0.12, 1.23±0.10 and 0.79±0.19, respectively. Those that used SS-EPI were 1.76±0.26, 1.38±0.20 and 1.05±0.27, respectively. Using unpaired t test (P<.05), we found a significant difference in each sequence between normal tissue (both PZ and TZ) and the cancer. Paired t test (P<.05) also registered a significant difference between LSDI and SS-EPI. Mean SNR for DWI using LSDI was 16.49±5.03, while the DWI using SS-EPI was 18.85±9.26. The difference between the SNR of each sequence was not statistically significant by paired t test.Conclusion
We found that ADCs using LSDI and SS-EPI showed similar tendencies in the same patients. However, in all regions, LSDI ADCs had smaller standard deviations than SS-EPI ADCs. 相似文献116.
The notion of r-stackedness for simplicial polytopes was introduced by McMullen and Walkup in 1971 as a generalization of stacked polytopes. In this paper, we define the r-stackedness for triangulated homology manifolds and study its basic properties. In addition, we find a new necessary condition for face vectors of triangulated manifolds when all the vertex links are polytopal. 相似文献
117.
In this paper, we are concerned with the uniqueness and the non-degeneracy of positive radial solutions for a class of semilinear elliptic equations. Using detailed ODE analysis, we extend previous results to cases where nonlinear terms may have sublinear growth.As an application, we obtain the uniqueness and the non-degeneracy of ground states for modified Schr¨odinger equations. 相似文献
118.
Soga S Shirai H Kobori M Hirayama N 《Journal of chemical information and modeling》2008,48(8):1679-1685
The idea that there should be a specific site on a protein for a particular functional small molecule is widespread. It is, however, usually not so easy to understand what characteristics of the site determine the binding ability of the functional small molecule. We have focused on the concurrence rate of the 20 standard amino acids at such binding sites. In order to correlate the concurrence rate and the specific binding site, we have analyzed high-quality X-ray structures of complexes between proteins and small molecules. A novel index characterizing the binding site based on the concurrency rate has been introduced. Using this index we have identified that there is a specific concavity designated as a chemocavity where a specific group of small molecules, i.e., canonical molecular group, is highly inclined to be bound. This study has demonstrated that a chemocavity is reserved for a specific canonical molecular group, and the prevalent idea has been confirmed. 相似文献
119.
Kenshu Fujiwara Masanori Kobayashi Fuyuki Yamamoto Yu-ichi Aki Mariko Kawamura Daisuke Awakura Seiji Amano Azusa Okano Akio Murai Hidetoshi Kawai Takanori Suzuki 《Tetrahedron letters》2005,46(30):5067-5069
The common left-half [C31-C33(OC1-C7)-C40] part of pectenotoxins has been synthesized convergently from the C31-C35, C36-C40, and C1-C7 parts. The C31-C35 part, prepared via a new route shorter than our previous route, was coupled with the C36-C40 part through reductive lithiation and addition reactions to give an adduct stereoselectively, which was converted to a cyclic acetal corresponding to the C31-C40 part. The left-half was synthesized by a three-step process including esterification of the C31-C40 part with the C1-C7 part. 相似文献
120.
The title sterically crowded di-9-anthrylethyne derivative with 3,5-iPr2-phenyl groups at 1-position showed a barrier to rotation about the acetylenic axis of 18.0 kcal mol−1 based on a dynamic NMR study, which is an extremely high value for acyclic diarylethynes. The mechanism of the dynamic stereochemistry and the substituent effect on the rotational barrier are discussed. 相似文献