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161.
Yukita Shunpei Suzuki Yuto Shiokawa Naoyuki Kobayashi Takayoshi Tokunaga Eiji 《Optical Review》2018,25(2):205-214
Optical Review - The “anomalous” Pockels effect is a phenomenon that a light beam passing between two electrodes in an aqueous electrolyte solution is deflected by an AC voltage applied... 相似文献
162.
The global and macrocyclic aromaticity of porphyrinoids was characterized using our graph theory of aromaticity. The sequential line plots of topological resonance energy (TRE) against the number of π-electrons (N(π)) for different porphyrinoids are similar with four major extrema to those for five-membered heterocycles. This supports the view that five-membered rings are the main origin of global aromaticity in porphyrinoids. Macrocyclic circuits contribute significantly to macrocyclic π-circulation but modestly to global aromaticity. Macrocyclic aromaticity/antiaromaticity in oligopyrrolic macrocycles can be predicted by formally applying Hückel's [4n + 2] rule to an annulene-like main macrocyclic conjugation pathway (MMCP). This bridged annulene model can be justified by examining the contribution of individual macrocyclic circuits to macrocyclic aromaticity. A Hückel-like rule of macrocyclic aromaticity was found for porphyrinoid species. 相似文献
163.
Purpose
To assess peripheral tissue perfusion disorder in streptozotocin (STZ)-induced diabetic rats by using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI).Materials and Methods
A rat diabetes model was produced by intravenous injection of STZ. Diabetic rats were sustainably treated with either saline or insulin using an Alzet osmotic pump. Hind paw tissue perfusion was measured by signal intensity (SI) enhancement after gadolinium diethylenetriaminepentaacetic acid injection in DCE-MRI study and quantified using the initial area under the SI-time curve (IAUC). Peripheral tissue uptake of [14C]iodoantipyrine (IAP) was also determined as a marker of tissue blood flow for comparison with the IAUC value indicating tissue perfusion.Results
STZ caused hyperglycemia at 1 and 2 weeks after injection. Treatment with insulin significantly alleviated hyperglycemia. At 2 weeks after STZ injection, peripheral tissue perfusion was clearly reduced in the diabetic rats and its reduction was significantly improved in the insulin-treated diabetic rats. Tissue perfusion evaluated by DCE-MRI was similar to the tissue blood flow measured by [14C]IAP uptake.Conclusion
Our findings demonstrated that DCE-MRI can assess peripheral tissue perfusion disorder in diabetes. DCE-MRI could be suitable for noninvasive evaluation of peripheral tissue perfusion in both preclinical and clinical studies. It may also be useful for developing novel drugs to protect against diabetic vascular complications. 相似文献164.
Isomura Y Narushima T Kawasaki H Yonezawa T Obora Y 《Chemical communications (Cambridge, England)》2012,48(31):3784-3786
Surfactant-free, single-nano-sized copper nanoparticles (Cu NPs) (size: about 2 nm) were prepared by the DMF reduction method. The Cu NPs showed high catalytic activity (with a turnover number (TON) of up to 2.2 × 10(4)) in Ullmann-type cross-coupling of aryl halides with phenols under ligand-free conditions. 相似文献
165.
Yuto Miyatake Takaharu Yaguchi Takayasu Matsuo 《Journal of computational physics》2012,231(14):4542-4559
We consider structure preserving numerical schemes for the Ostrovsky equation, which describes gravity waves under the influence of Coriolis force. This equation has two associated invariants: an energy function and the L2 norm. It is widely accepted that structure preserving methods such as invariants-preserving and multi-symplectic integrators generally yield qualitatively better numerical results. In this paper we propose five geometric integrators for this equation: energy-preserving and norm-preserving finite difference and Galerkin schemes, and a multi-symplectic integrator based on a newly found multi-symplectic formulation. A numerical comparison of these schemes is provided, which indicates that the energy-preserving finite difference schemes are more advantageous than the other schemes. 相似文献
166.
Geometriae Dedicata - We introduce generalized Kazdan-Warner equations on Riemannian manifolds associated with a linear action of a torus on a complex vector space. We show the existence and the... 相似文献
167.
Chlorophyll molecules are well organized for efficient energy or electron transfer in a light-harvesting antenna or a reaction center of photosynthetic organisms. In order to make effective photosynthetic mimics, self-aggregates of natural chlorophylls and their synthetic analogues have been prepared with the specific intermolecular interactions. Many studies have been carried out to prepare aqueous chlorophyll aggregates by use of surfactants or chemical modifications of the natural pigments, because chlorophylls basically are poorly soluble in water. This review article focuses on the preparation and function of aqueous chlorophyll aggregates used in making artificial photosynthetic systems. 相似文献
168.
Pyrene‐Bridged Boron Subphthalocyanine Dimers: Combination of Planar and Bowl‐Shaped π‐Conjugated Systems for Creating Uniquely Curved π‐Conjugated Systems 下载免费PDF全文
Shota Nakano Yuto Kage Prof. Hiroyuki Furuta Prof. Nagao Kobayashi Prof. Soji Shimizu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(23):7706-7710
Pyrene‐bridged boron subphthalocyanine dimers were synthesized from a mixed‐condensation reaction of 2,7‐di‐tert‐butyl‐4,5,9,10‐tetracyanopyrene and tetrafluorophthalonitrile, and their syn and anti isomers arising from the result of connecting two bowl‐shaped boron subphthalocyanine molecules were successfully separated. Expansion of the conjugated system of boron subphthalocyanine through a pyrene bridge caused a redshift of the Q band absorption relative to the parent pyrene‐fused monomer, whereas combining the curved π‐conjugation of boron subphthalocyanine with the planar π‐conjugation of pyrene enabled facile embracement of C60 molecules, owing to the enhanced concave–convex π–π stacking interactions. 相似文献
169.
170.