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71.
72.
Silk‐Pectin Hydrogel with Superior Mechanical Properties,Biodegradability, and Biocompatibility
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Keiji Numata Shoya Yamazaki Takuya Katashima Jo‐Ann Chuah Naofumi Naga Takamasa Sakai 《Macromolecular bioscience》2014,14(6):799-806
A new method is developed to prepare silk hydrogels and silk‐pectin hydrogels via dialysis against methanol to obtain hydrogels with high concentrations of silk fibroin. The relationship between the mechanical and biological properties and the structure of the silk‐pectin hydrogels is subsequently evaluated. The present results suggest that pectin associates with silk molecules when the silk concentration exceeds 15 wt%, suggesting that a silk concentration of over 15 wt% is critical to construct interacting silk‐pectin networks. The silk‐pectin hydrogel reported here is composed of a heterogeneous network, which is different from fiber‐reinforced, interpenetrated networks and double‐network hydrogels, as well as high‐stiffness hydrogels (elastic modulus of 4.7 ± 0.9 MPa, elastic stress limit of 3.9 ± 0.1 MPa, and elastic strain limit of 48.4 ± 0.5%) with regard to biocompatibility and biodegradability. 相似文献
73.
Yamazaki Kazuyoshi Hosaka Makoto Yamada Kenichiro Ogata Takeshi Shimada Kenichi 《Optical Review》2016,23(5):848-858
Optical Review - A precise and fast method for controlling the reference-beam angle of an angular-multiplexed holographic data storage system (HDSS)—to achieve larger capacity and faster... 相似文献
74.
We describe the development of a phase-locked laser system tailored to an ion-trap-based quantum information processor with (40)Ca(+). Laser outputs from an extended cavity diode laser and a Ti:sapphire laser with output laser wavelengths of approximately 850 and 854 nm, respectively, were phase locked and used to excite a Raman transition between the D(3/2) and D(5/2) metastable states qubit. Development and the performance of the laser system are described. We also compare the characteristics and the benefits of the developed qubit coupling with those in the conventional approaches. 相似文献
75.
Toshimitsu Yamazaki M.J.A. Yoshinori Akaishi 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2007,83(5):144-150
We have studied the structure of K−pp comprehensively by solving this threebody system in a variational method, starting from the Ansatz that the Λ(1405) resonance (≡Λ*) is a K−p bound state. The structure of K−pp reveals a molecular feature, namely, the K− in Λ* as an “atomic center” plays a key role in producing strong covalent bonding with the other proton. We point out that strongly bound nuclear systems are formed by “super strong” nuclear force due to migrating real bosonic particles a la Heitler-London-Heisenberg, whereas the normal nuclear force is caused by mediating virtual mesons. We have shown that the elementary process, p + p → K+ + Λ* + p, which occurs in a short impact parameter and with a large momentum transfer, leads to unusually large self-trapping of Λ* by the involved proton, since the Λ*-p system exists as a compact doorway state propagating to K−pp. 相似文献
76.
N. Kuroda S. Ulmer D. J. Murtagh S. Van Gorp Y. Nagata M. Diermaier S. Federmann M. Leali C. Malbrunot V. Mascagna O. Massiczek K. Michishio T. Mizutani A. Mohri H. Nagahama M. Ohtsuka B. Radics S. Sakurai C. Sauerzopf K. Suzuki M. Tajima H. A. Torii L. Venturelli B. Wünschek J. Zmeskal N. Zurlo H. Higaki Y. Kanai E. Lodi Rizzini Y. Nagashima Y. Matsuda E. Widmann Y. Yamazaki 《Hyperfine Interactions》2015,235(1-3):13-20
In order to test CPT symmetry between antihydrogen and its counterpart hydrogen, the ASACUSA collaboration plans to perform high precision microwave spectroscopy of ground-state hyperfine splitting of antihydrogen atom in-flight. We have developed an apparatus (“cusp trap”) which consists of a superconducting anti-Helmholtz coil and multiple ring electrodes. For the preparation of slow antiprotons and positrons, Penning-Malmberg type traps were utilized. The spectrometer line was positioned downstream of the cusp trap. At the end of the beamline, an antihydrogen beam detector was located, which comprises an inorganic Bismuth Germanium Oxide (BGO) single-crystal scintillator housed in a vacuum duct and surrounding plastic scintillators. A significant fraction of antihydrogen atoms flowing out the cusp trap were detected. 相似文献
77.
78.
Dr. Soji Shimizu Yu Haseba Mariko Yamazaki Genji Kumazawa Prof. Nagao Kobayashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(16):4822-4828
The first example of the control of porphyrinoid chromophore symmetry based on the positional isomerism of peripheral substituents has been achieved by preparing tetraazaporphyrins (TAPs) with C4h, D2h, C2v, and Cs symmetry due to the relative arrangement of peripheral tert‐butylamino and cyano groups as push and pull substituents, respectively. The four structural isomers were successfully isolated and characterized by 1H NMR spectroscopy and X‐ray crystallography. The band morphology in the Q‐band region varies depending on the molecular symmetry due to the significant perturbation introduced into the chromophore by the push and pull substituents. The C4h and C2v isomers exhibit a single Q band, whereas the Q bands of the D2h and Cs isomers show a marked splitting. The magnetic circular dichroism spectra indicate that the push–pull TAPs retain the properties of the 16‐membered 18π‐electron perimeter generally observed for porphyrinoids. Theoretical calculations have demonstrated that the perturbation introduced by the substituents lowers the D4h symmetry of the parent TAP π‐conjugated system, and this results in significant spectral changes. A novel approach to the fine‐tuning of the spectral properties of porphyrinoids based on changes in the chromophore symmetry is described. 相似文献
79.
Nobuyasu Hanari Taichi Yamazaki Nobuyasu Itoh Takashi Yarita Naomi Fujiki Ryoko Iwasawa Yoshie Aoyagi Masahiko Numata 《Accreditation and quality assurance》2014,19(5):391-396
A certified reference material (CRM) for the determination of perfluorooctanoic acid (PFOA) has been issued as NMIJ CRM 4056-a by the National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology (NMIJ/AIST). Purity (kg kg?1) based on a titration method was determined by subtracting the mass fractions of impurities measured using liquid chromatography/mass spectrometry (LC/MS) from those of acids expressed as PFOA measured by a neutralization potentiometric titration. To validate an obtained result, purity based on a mass balance method was determined by subtracting the mass fractions of impurities, measured using LC/MS, Karl-Fischer titration (KFT), and vacuum evaporation, from 1 kg kg?1. Results from both titration and mass balance methods were in agreement within the accepted limits of uncertainty. The certified purity of NMIJ CRM 4056-a was determined to be 0.959 kg kg?1, calculated as the mean of the results obtained with the two methods. The standard uncertainty of the certified purity was evaluated from purity evaluations as well as from sample homogeneity and stability obtained from LC/MS and KFT analyses. Consequently, the expanded uncertainty was estimated to be 0.005 kg kg?1 with a coverage factor of k = 2. 相似文献