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961.
Fujita D Takahashi A Sato S Fujita M 《Journal of the American Chemical Society》2011,133(34):13317-13319
Thermodynamically controlled platinum(II) spherical complexes were synthesized via temporary labilization of inert Pt(II)-pyridine bonds by the addition of the strong hydrogen-bond donor 2,2,2-trifluoroethanol (TFE), which weakens the pyridine-metal interaction. The platinum complex was stably trapped after removal of TFE and showed higher acid durability than its palladium counterpart. 相似文献
962.
Yamakoshi H Dodo K Okada M Ando J Palonpon A Fujita K Kawata S Sodeoka M 《Journal of the American Chemical Society》2011,133(16):6102-6105
Click-free imaging of the nuclear localization of an alkyne-tagged cell proliferation probe, EdU, in living cells was achieved for the first time by means of Raman microscopy. The alkyne tag shows an intense Raman band in a cellular Raman-silent region that is free of interference from endogenous molecules. This approach may eliminate the need for click reactions in the detection of alkyne-labeled molecules. 相似文献
963.
For given graphs G and H and an integer k, the Gallai–Ramsey number is defined to be the minimum integer n such that, in any k coloring of the edges of Kn, there exists a subgraph isomorphic to either a rainbow coloring of G or a monochromatic coloring of H. In this work, we consider Gallai–Ramsey numbers for the case when G=K3 and H is a cycle of a fixed length. 相似文献
964.
Dedachi K Hirakawa T Fujita S Khan MT Sylte I Kurita N 《Journal of computational chemistry》2011,32(14):3047-3057
Thermolysin (TLN) is a metalloprotease widely used as a nonspecific protease for sequencing peptide and synthesizing many useful chemical compounds by the chemical industry. It was experimentally shown that the activity and functions of TLN are inhibited by the binding of many types of amino acid dipeptides. However, the binding mechanisms between TLN and dipeptides have not been clarified at the atomic and electronic levels. In this study, we investigated the binding mechanisms between TLN and four dipeptides. Specific interactions and binding free energies (BFEs) between TLN and the dipeptides were calculated using molecular simulations based on classical molecular dynamics and ab initio fragment molecular orbital (FMO) methods. The molecular systems were embedded in solvating water molecules during calculations. The calculated BFEs were qualitatively consistent with the trend of the experimentally observed inhibition of TLN activity by binding of the dipeptides. In addition, the specific interactions between the dipeptides and each amino acid residue of TLN or solvating water molecules were elucidated by the FMO calculations. 相似文献
965.
966.
967.
Sagisaka M Fujita Y Shimizu Y Osanai C Yoshizawa A 《Journal of colloid and interface science》2011,364(2):400-406
In this present study, we report on new methodology for determining the Critical Micelle Concentration (CMC) of a neutral surfactant Triton X-100 (TX-100) both in aqueous and non-aqueous media based on a non-invasive approach. The presence of the phenyl moiety of TX-100 was made use of as an intrinsic fluorophore and steady-state and time-resolved spectroscopy has been used to characterize the micellar systems. There are reports that external fluorophores may bring about some structural changes in the systems and the perturbations caused by these fluorophores in micellar systems may affect the shape and size of the micelles. We have also used three probes namely ANS, Rh6G and C-480 to determine the CMC of TX-100 both in aqueous and non-aqueous media and the values obtained agree very well with those estimated by the non-invasive techniques. Interestingly, for our system, we have conclusively proved that the external probes have almost no effect on the process of micellization. Although, both the invasive and non-invasive technologies report almost the same values of CMC, yet the latter methodology is free from any external perturbations and this makes the micellar/reverse micellar system, which may interact with other biological systems less prone to any physical distortions. 相似文献
968.
Takahashi M Ohno S Fujita N Sengoku T Yoda H 《Journal of colloid and interface science》2011,356(2):536-542
Detailed exploratory and mechanistic investigations on spontaneous formation of dye-functionalized gold nanoparticles (GNPs) using dye-based reverse micellar systems are described in this publication. The accumulated results from spectroscopic and microscopic investigations demonstrated that water molecules confined within nanoscopic enclosure of the self-assembled reverse micelles played critical role in the redox processes of aurate ions to produce GNPs, which are assumed to have approximately constant size distributions. The resulting dye-functionalized GNPs were found to offer their absorption and fluorescence emission tunability by changing the medium polarity as well as to exhibit excellent film-forming properties to give optically homogeneous polystyrene thin films. These key findings in addition to broad applicability of the self-assembling process with a variety of dye analogues have led to a conclusion that the protocol presented here serves as a versatile synthetic method to provide a potential convenience for future development of new organic-inorganic hybrid nanomaterials. 相似文献
969.
We built a differential optical absorption spectroscopy system to measure near-surface CO2 absorption in the atmosphere using a nanosecond white light continuum. The white light laser can cover wavelengths ranging from 420 to 2400 nm, where the CO2 and H2O absorption lines are located. At an optical path length of 568 m, it was possible to evaluate atmospheric CO2 concentration from absorption bands of CO2 and H2O in the vicinity of 2000 nm detected by broadband white light simultaneously. 相似文献
970.
Yonggang Jiang Takayuki Fujita Minoru UeharaYuki Iga Taichi HashimotoXiuchun Hao Kohei HiguchiKazusuke Maenaka 《Journal of magnetism and magnetic materials》2011,323(21):2696-2700
The silicon molding technique is described for patterning of NdFeB/Ta multilayered magnetic films and NdFeB magnetic powder at the micron scale. Silicon trenches are seamlessly filled by 12-μm-thick NdFeB/Ta multilayered magnetic films with a magnetic retentivity of 1.3 T. The topography image and magnetic field distribution image are measured using an atomic force microscope and a magnetic force microscope, respectively. Using a silicon molding technique complemented by a lift-off process, NdFeB magnetic powder is utilized to fabricate magnetic microstructures. Silicon trenches as narrow as 20 μm are filled by a mixture of magnetic powder and wax powder. The B-H hysteresis loop of the patterned magnetic powder is characterized using a vibrating sample magnetometer, which shows a magnetic retentivity of approximately 0.37 T. 相似文献