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11.
Yokoi  Naomichi  Aizu  Yoshihisa 《Optical Review》2021,28(4):440-448

We have previously presented a blood perfusion parameter by means of the spatial contrast of speckle patterns observed for blood perfusion in skin tissue and a blood vessel. This parameter permits us to visualize a relative blood perfusion distribution from a single speckle pattern. Therefore, it can estimate the blood perfusion with a frame rate of an imaging device employed. This parameter is, however, dependent on the speckle size and the condition of image processing of speckle patterns. In the present study, we estimated this condition with relation to the speckle size for obtaining high sensitivity and good linearity of the parameter to the blood perfusion. Experiments were conducted for ground-glass model, flow model and human wrist to investigate perfusion sensing characteristics of the present parameter.

  相似文献   
12.
The X-ray crystal structure of the title complex, Co(Cl2bprpi) is described. In this complex the Co(II) center displays a distorted octahedral coordination geometry. The piperazine ring exhibits boat conformation, forming chelate rings and capping the Co atom. The N2-Col-N3 angle is 69.41(15) degrees, extremely smaller than 90 degrees. Because the small angle causes a large steric hindrance, the piperazine ring can be effective as an ion size-recognition site. The molecular structure is stabilized by intramolecular N-H...O hydrogen bonds and Cl...H contacts.  相似文献   
13.
The confined space synthesis method has been applied to the preparation of sodium tantalate (NaTaO(3)); hydrothermal reaction of NaOH and Ta(2)O(5) was carried out in the pores of a three-dimensional mesoporous carbon, which was replicated by the colloidal array of silica nanospheres (SNSs) 20 nm in size. This approach led to the formation of a colloidal array of NaTaO(3) nanoparticles 20 nm in size with a surface area of 34 m(2) g(-1). The photocatalytic performance of the colloidal array of NaTaO(3) nanoparticles for overall water splitting under UV irradiation (λ > 200 nm) was evaluated after loading a NiO cocatalyst onto NaTaO(3) samples. The NiO-loaded NaTaO(3) nanoparticles showed photocatalytic activity for overall water splitting more than three times as high as non-structured bulk NaTaO(3) particles.  相似文献   
14.
Separation of various alcohols and water through a membrane was carried out by means of a hydrogen-bonding interaction. A membrane obtained from poly(maleimide-co-acrylonitrile) was effective for a selective separation of water from aqueous alcohol solution by pervaporation technique. Spectroscopic analyses verified that this high selectivity was attributed to the hydrogen-bonding interaction between water and maleimide units in the membrane.  相似文献   
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Storage and retrieval of a squeezed vacuum was successfully demonstrated using electromagnetically induced transparency. The squeezed vacuum pulse having a temporal width of 930 ns was incident on the laser cooled 87Rb atoms with an intense control light in a coherent state. When the squeezed vacuum pulse was slowed and spatially compressed in the cold atoms, the control light was switched off. After 3 mus of storage, the control light was switched on again, and the squeezed vacuum was retrieved, as was confirmed using the time-domain homodyne method.  相似文献   
17.
Photoluminescence of strongly correlated organic radical 1,3,5-trithia-2,4,6-triazapentalenyl (TTTA) crystals was measured at room temperature in order to elucidate the relaxation process in the excited state, which is responsible for an initiation of the photoinduced magnetic phase transition in this material. The electronic structure and luminescence properties of TTTA molecule were also investigated to clarify the relaxation process. We found that a luminescence band lies at 1.8 eV in the high-temperature (HT) phase crystal having almost same characteristics as that in TTTA molecule, suggesting that the intramolecular lattice distortion plays an important role for the relaxation process. On the other hand, a broad luminescence band appears at 1.4 eV with a large Stokes shift in the low-temperature (LT) phase crystal. The large Stokes shift observed shows that rearrangement of the dimerized TTTA molecules toward the evenly spaced radicals takes place due to a large intermolecular lattice distortion. This molecular rearrangement in the excited state initiates the photoinduced magnetic phase transition from the LT to HT phases in this material.  相似文献   
18.
Optical trapping and guiding using laser have been proven to be useful for non-contact and non-invasive manipulation of small objects such as biological cells, organelles within cells, and dielectric particles. We have numerically investigated so far the motion of a Brownian particle suspended in still water under the illumination of a speckle pattern generated by the interference of coherent light scattered by a rough object. In the present study, we investigate numerically the motion of a particle in a water flow under the illumination of a speckle pattern that is at rest or in motion. Trajectory of the particle is simulated in relation with its size, flow velocity, maximum irradiance, and moving velocity of the speckle pattern to confirm the feasibility of the present method for performing optical trapping and guiding of the particle in the flow.  相似文献   
19.
Two (ONO pincer)ruthenium‐complex‐bound norvalines, Boc?[Ru(pydc)(terpy)]Nva?OMe ( 1 ; Boc=tert‐butyloxycarbonyl, terpy=terpyridyl, Nva=norvaline) and Boc?[Ru(pydc)(tBu‐terpy)]Nva?OMe ( 5 ), were successfully synthesized and their molecular structures and absolute configurations were unequivocally determined by single‐crystal X‐ray diffraction. The robustness of the pincer Ru complexes and norvaline scaffolds against acidic/basic, oxidizing, and high‐temperature conditions enabled us to perform selective transformations of the N‐Boc and C?OMe termini into various functional groups, such as alkyl amide, alkyl urea, and polyether groups, without the loss of the Ru center or enantiomeric purity. The resulting dialkylated Ru‐bound norvaline, n‐C11H23CO?l ‐[Ru(pydc)(terpy)]Nva?NH‐n‐C11H23 (l ‐ 4 ) was found to have excellent self‐assembly properties in organic solvents, thereby affording the corresponding supramolecular gels. Ru‐bound norvaline l ‐ 1 exhibited a higher catalytic activity for the oxidation of alcohols by H2O2 than parent complex [Ru(pydc)(terpy)] ( 11 a ).  相似文献   
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