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951.
In order to achieve high-density recording, the detailed behavior of thermal degradation should be investigated. In this paper, the degradation of magnetization of high-density recording medium is examined using the 3-D finite element method (FEM) combined with the modeling of Stoner–Wohlfarth (SW) particles and Neel–Arrhenius switching probability. It is shown that the anisotropy field Hk suppressed the thermal degradation and the saturation magnetization Ms enhances it. The thermal degradation is also changed by the amplitude of magnetization. 相似文献
952.
Tsuchida Shirou Takahashi Rina Yabe Kurumi Hamaue Naoya Aoki Takashi 《Cellulose (London, England)》2022,29(6):3025-3033
Cellulose - A method for the preparation of dialdehyde cellulose disks (DACD) and subsequent diamino cellulose disks (DAmCD) was developed. DACD was prepared by oxidizing filter paper with sodium... 相似文献
953.
954.
Dr. Takeshi Fujita Yutaro Kobayashi Dr. Ikko Takahashi Ryutaro Morioka Dr. Tomohiro Ichitsuka Prof. Dr. Junji Ichikawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(2):e202103643
Nickel-catalyzed reductive cross-coupling of allylic difluorides with aryl iodides was achieved via allylic C−F bond activation. Based on this protocol, a series of γ-arylated monofluoroalkenes were synthesized in moderate to high yields with high Z-selectivities. Mechanistic studies suggest that the C−I bonds of the aryl iodides and the C−F bonds of the allylic difluorides were cleaved via oxidative addition and β-fluorine elimination, respectively, where the oxidative addition of less reactive C−F bonds was avoided to permit their transformation. 相似文献
955.
Takahashi Hiroaki Park Ki Chul Nomura Masao Shibahara Hiroki Miura Hanako Ohishi Yukiko Yuki Mami Tsukahara Takehiko 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):327-336
Journal of Radioanalytical and Nuclear Chemistry - The influence of extraction process on Cs isotope ratios was investigated by thermal ionization mass spectrometry (TIMS) for nitric-acid (HNO3)... 相似文献
956.
957.
Akira Takahashi Ryu Yuzaki Yoshihito Ishida Atsushi Kameyama 《Journal of polymer science. Part A, Polymer chemistry》2019,57(24):2442-2449
Ring‐expansion polymerization (REP) of thiiranes was investigated using 3H‐benzothiazol‐2‐one (BT) as the cyclic aromatic thiourethane initiator in the presence of tetrabutylammonium chloride (TBAC) catalyst. The polymerization proceeded in a well‐controlled manner to afford cyclic polysulfides with one BT moiety per macrocycle, as confirmed by MALDI‐TOF MS spectroscopy. Differential scanning calorimetry (DSC) measurement of the obtained cyclic polysulfides revealed slight decrease in the glass‐transition temperature as the increase in the molecular weight, supporting the cyclic topology of the products. Postpolymerization of thiiranes using the BT‐initiated cyclic polysulfide as the macroinitiator afforded the ring‐expanded product while maintaining the narrow polydispersity and well‐defined cyclic structure, which enabled precise synthesis of cyclic block copolymer with different thiirane combination. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 2442–2449 相似文献
958.
Point-of-care testing (POCT) devices have evolved to provide beneficial information about an individual's health whenever needed. Enzyme-based analytical devices have facilitated the highly selective detection of numerous biological molecules and ions. Enzymes are commonly used as the tags of recognition components, such as antibodies, to generate and amplify detection signals. Particularly, alkaline phosphatase (ALP) is one of the most widely used enzymes because of its high turnover number and low cost. Rapid response time and the incorporation of many sensors fabricated by micro/nano processing technologies are the advantages in using electrochemical devices as analytical tools. Therefore, ALP-based electrochemical devices have potential applications for more practical POCT platforms. This review summarizes recent research progress of ALP-based electrochemical devices for POCT. In addition to ALP substrates, the application of ALP-based immunosensors, aptasensors, and DNAzyme sensors are discussed. 相似文献
959.
Miho Shimada Yuji Masuda Yukio Yamada Masahide Itoh Motoji Takahashi Toyohiko Yatagai 《Optical Review》2000,7(4):348-352
Quantitative analysis of human skin color is needed in the medical and cosmetic fields. Because of the strong light scattering by biological tissues, however, analysis of skin color has not yet been fully successful. Human skin color is dominated by the colors of blood and melanin which are modified by scattering. Exposure of human skin to hot water or UV-ray changes its color because the absorbance spectrum of reflection from the human skin, and the changes in the absorbance spectra of reflection reflect the absorbance spectra of blood and melanin which are the absorption spectrum distorted by scattering. By applying the modified Lambert-Beer law, the absorbance spectrum of reflection from human skin can be expressed proportional to those distorted absorbance spectra of blood and melanin. Multiple linear regression analysis is successfully used to reproduce the absorbance spectrum of reflection from human skin from the distorted absorbance spectra of blood and melanin. 相似文献
960.