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81.
Two‐photon microscopy (TPM) has become an indispensible tool in biology and medicine owing to the capability of imaging the intact tissue for a long period of time. To make it a versatile tool in biology, a variety of two‐photon probes for specific applications are needed. In this context, many research groups are developing two‐photon probes for various applications. In this Focus Review, we summarize recent results on model studies and selected examples of two‐photon probes that can detect intracellular free metal ions in live cells and tissues to provide a guideline for the design of useful two‐photon probes for various in vivo imaging applications. 相似文献
82.
Myung Eun Suk 《Molecules (Basel, Switzerland)》2021,26(13)
By using the advantages of carbon nanotubes (CNTs), such as their excellent mechanical properties and low density, CNT-reinforced metal matrix composites (MMCs) are expected to overcome the limitations of conventional metal materials, i.e., their high density and low ductility. To understand the behavior of composite materials, it is necessary to observe the behavior at the molecular level and to understand the effect of various factors, such as the radius and content of CNTs. Therefore, in this study, the effect of the CNT radius and content on the mechanical properties of CNT-Al composites was observed using a series of molecular dynamics simulations, particularly focusing on MMCs with a high CNT content and large CNT diameter. The mechanical properties, such as the strength and stiffness, were increased with an increasing CNT radius. As the CNT content increased, the strength and stiffness increased; however, the fracture strain was not affected. The behavior of double-walled carbon nanotubes (DWNTs) and single-walled carbon nanotubes (SWNTs) was compared through the decomposition of the stress–strain curve and observations of the atomic stress field. The fracture strain increased significantly for SWNT-Al as the tensile force was applied in the axial direction of the armchair CNTs. In the case of DWNTs, an early failure was initiated at the inner CNTs. In addition, the change in the elastic modulus according to the CNT content was predicted using the modified rule of mixture. This study is expected to be useful for the design and development of high-performance MMCs reinforced by CNTs. 相似文献
83.
Generalized vector variational inequality and fuzzy extension 总被引:4,自引:0,他引:4
A generalized vector variational inequality (GVVI) is considered. We establish the existence theorem for (GVVI) under assumptions of C-pseudomonotonicity and V-hemicontinuity. From our existence theorem, we obtain the fuzzy extension of a result of Chen and Yang. 相似文献
84.
Myung Geun Kim 《Journal of Applied Mathematics and Computing》2002,10(1-2):111-118
We study the influence of observations on testing a linear hypothesis using single and multiple case-deletions. The change in the F-test statistic due to case-deletions is shown to be completely determined by two externally Studentized residuals. These residuals are used for investigating the outlyingness when there are linear constraints or not. An illustrative example is given. It shows the usefulness of case-deletions. 相似文献
85.
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87.
We have demonstrated the synthesis of one-dimensional (1D) structures of bismuth oxide (Bi2O3) by a reaction of a trimethylbismuth (TMBi) and oxygen (O2) mixture at 450 °C. Scanning electron microscopy showed that the product consisted of 1D materials with width or diameters less than 1 μm and lengths up to several tens of micrometers. The X-ray energy dispersive spectroscopy revealed that the materials contained elements of Bi and O. The results of X-ray diffraction and selected area electron diffraction pattern indicated that the obtained Bi2O3 were crystalline with monoclinic structure. 相似文献
88.
Jin Su Park Tae In Ryu Myungkwan Song Kyung‐Jin Yoon Myung Jin Lee In Ae Shin Gi‐Dong Lee Jae Wook Lee Yeong‐Soon Gal Sung‐Ho Jin 《Journal of polymer science. Part A, Polymer chemistry》2008,46(18):6175-6184
The following noble series of soluble π‐conjugated statistical copolymers was synthesized by palladium catalyzed Suzuki polymerization: poly[(9,9‐dioctylfluorene)‐alt‐(4,7‐bis(3′,3′‐dihepyl‐3,4‐propylenedioxythienyl)‐2,1,3‐benzothiadiazole)] (PFO‐PTBT) derived from poly(9,9‐dioctylfluorene) (PFO) and poly[(4,7‐bis(3′,3′‐dihepyl‐3,4‐propylenedioxythienyl)‐2,1,3‐benzothiadiazole)] poly(heptyl4‐PTBT). The structure and properties of these polymers were characterized using 1H‐, 13C‐NMR, UV–visible spectroscopy, elemental analysis, GPC, DSC, TGA, photoluminescence (PL), and cyclic voltammetry (CV). The statistical copolymers, PFO‐PTBT (9:1, 8.4:1.6, 6.5:3.5), were soluble in common organic solvents and easily spin coated onto indium‐tin oxide (ITO) coated glass substrates. The weight‐average molecular weight (Mw) and polydispersity of the PFO‐PTBT ranged from (1.0–4.2) × 104 and 1.5–2.3, respectively. Bulk heterojunction photovoltaic cells with an ITO/PEDOT/PFO‐PTBT:PCBM/LiF/Al configuration were fabricated, and the devices using PFOPTBT (6.5:3.5) showed the best performance compared with those using PFO‐PTBT (9:1, 8.4:1.6). A maximum power conversion efficiency (PCE) of 0.50% (Voc = 0.66 V, FF = 0.29) was achieved with PFO‐PTBT (6.5:3.5). © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6175–6184, 2008 相似文献
89.
90.
In this paper, we consider a nondifferentiable convex vector optimization problem (VP), and formulate several kinds of vector
variational inequalities with subdifferentials. Here we examine relations among solution sets of such vector variational inequalities
and (VP).
Mathematics Subject classification (2000). 90C25, 90C29, 65K10
This work was supported by the Brain Korea 21Project in 2003. The authors wish to express their appreciation to the anonymous
referee for giving valuable comments. 相似文献