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991.
Digital radiography (DR) and whole-body fluorescent optical imaging (WFOI) have been widely applied in the field of molecular imaging, with the advantages in tissues and functional imaging. The integration of them contributes to the development and discovery of medicine. We introduce an equipment, performance of which is better than that of another molecular imaging system manufactured by Kodak Corp. It can take real-time small animal imaging in vivo, with lower cost and shorter development cycle on the LabVIEW platform. At last, a paradigm experiment on a nude mouse with green fluorescent protein (GFP) transgenic tumor is given to present a real-time DR-WFOI fusion simultaneous image. 相似文献
992.
聚并苯导电高分子材料的ESR研究 总被引:4,自引:0,他引:4
本文对由热固性酚醛树脂通过高温裂解制备的聚并苯导电高分子本征材料的ESR进行了研究。结果表明在各种裂解温度下制备的样品由于其结构不同,表现在ESR线宽、自旋浓度、线型的峰高比等差异很大,并给予了解释。 相似文献
993.
Yanrong Song Peng Zhang Xinping Zhang Boxia Yan Yi Zhou Yong Bi Zhigang Zhang 《中国光学快报(英文版)》2008,6(4)
An intracavity frequency-doubled vertical external cavity surface emitting laser (VECSEL) with green light is demonstrated. The fundamental frequency laser cavity consists of a distributed Bragg reflector (DBR) of the gain chip and an external mirror. A 12-mW frequency-doubled output has been reached at 540 nm with a nonlinear crystal LBO when the fundamental frequency output is 44 mW at 1080 nm. The frequency doubling efficiency is about 30%. 相似文献
994.
995.
Busnel O Bi L Dali H Cheguillaume A Chevance S Bondon A Muller S Baudy-Floc'h M 《The Journal of organic chemistry》2005,70(26):10701-10708
[structure: see text] A solid-phase fluorenylmethyloxycarbonyl (Fmoc)-based synthesis strategy is described for "mixed" aza-beta3-peptides as well as a convenient general approach for their required building blocks, the aza-beta3-amino acid residues (aza-beta3-aa). These monomers allow the synthesis of relatively large quantities of pure mixed aza-beta3-peptides. The required Fmoc-substituted aza-beta3-amino acids are accessible by convenient synthesis, and a number of monomers including those containing side chains with functional groups have been synthesized. The method was applied toward the solid-phase synthesis of aza-beta3-peptide mimetics of a biologically active histone H4 sequence. 相似文献
996.
997.
The ruthenium(II)-supported heteropolyanions [HXW7O28Ru(dmso)3]6-(X=P, 1; As, 2) are composed of a Ru(dmso)3 group attached to an unprecedented heptatungstate fragment via two Ru-O-W bonds and one Ru-O-X bond, which represents a fundamentally novel mode of Ru-coordination to a polyoxoanion framework. Multinuclear 183W, 31P, 13C, and 1H NMR studies indicate high stability of 1 and 2 in solution. 相似文献
998.
A novel catalyst for the Fenton reaction was prepared by immobilizing Fe(III) onto collagen fiber and its high activity as a catalyst for degradation of dyes under irradiation of UVC was proved. 相似文献
999.
Single-crystalline wurtzite ZnS nanobelts are synthesized by the vapor phase transport (VPT) process. When oxidized, a single-crystalline ZnS nanobelt turns into a ZnO nanotwin belt containing two twinning parts with a sharp and clear edge, which is a (0001) twinning plane parallel to and running through the length direction. The two twinning parts in a ZnO nanotwin belt have the same crystalline direction, [0001], along their width, and the and crystalline directions along the length direction. On some ZnO nanobelts, nanovoids appear along the twinning planes and when those nanovoids connect with each other, one original ZnS nanobelt can divide into two single-crystalline ZnO nanobelts with quite clear edges. 相似文献
1000.
We propose a phenomenological form of the charged lepton mass matrix which extends the idea of a ”lopsided” mass matrix found
in the literature. The features of the form are that both the 2-3 and 1-3 elements of the charged lepton mass matrix are of
order 1 and that the small elements have a new structure. This form leads to the interesting result that both large atmospheric
and solar neutrino mixing can be accounted for by the matrix. Another interesting result of this mass matrix is that it leads
to very small 1-3 mixing in the lepton sector and can suppress the branching ratio of under the present experimental limit in the supersymmetric see-saw case.
Received: 3 October 2002 / Revised version: 10 November 2002 / Published online: 24 January 2003
RID="a"
ID="a" e-mail: bixj@mail.tsinghua.edu.cn
RID="b"
ID="b" e-mail: dyb@itp.ac.cn 相似文献