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731.
A porous media theory has been proposed to characterize oxygen transport processes associated with membrane blood oxygenation devices. For the first time, a rigorous mathematical procedure based a volume averaging procedure has been presented to derive a complete set of the governing equations for the blood flow field and oxygen concentration field. As a first step towards a complete three-dimensional numerical analysis, one-dimensional steady case is considered to model typical membrane blood oxygenator scenarios, and to validate the derived equations. The relative magnitudes of oxygen transport terms are made clear, introducing a dimensionless parameter which measures the distance the oxygen gas travels to dissolve in the blood as compared with the blood dispersion length. This dimensionless number is found so large that the oxygen diffusion term can be neglected in most cases. A simple linear relationship between the blood flow rate and total oxygen transfer rate is found for oxygenators with sufficiently large membrane surface areas. Comparison of the one-dimensional analytic results and available experimental data reveals the soundness of the present analysis. 相似文献
732.
Nagaoka K Isobe M Toi K Shimizu A Fujisawa A Ohshima S Nakano H Osakabe M Todo Y Akiyama T Nagashima Y Suzuki C Nishimura S Yoshimura Y Matsuoka K Okamura S 《Physical review letters》2008,100(6):065005
The internal behavior of fast ions interacting with magnetohydrodynamic bursts excited by energetic ions has been experimentally investigated in the compact helical system. The resonant convective oscillation of fast ions was identified inside the last closed-flux surface during an energetic-particle mode (EPM) burst. The phase difference between the fast-ion oscillation and the EPM, indicating the coupling strength between them, remains a certain value during the EPM burst and drives an anomalous transport of fast ions. 相似文献
733.
Yoshifumi Nagumo Kazuya Tanaka Kaushal Tewari Khwankaew Thiraporn Toru Tsuchida Toshimitsu Honma Norikuni Ohtake Kuni Sueyoshi Yoshihiko Takahashi Takuji Ohyama 《Journal of chromatography. A》2009,1216(29):5614-5618
A rapid and simple method for determination of cyanamide in fertilizer, soil and plants has been developed. In this method, cyanamide is extracted with 2% acetic acid and the extract separated by centrifugation. It is then purified by passing through a membrane filter. The extract was derivatized with 6-aminoquinolyl-N-hydroxysuccinimidyl-carbamate and the derivatized compound separated by ultra-high-pressure liquid chromatography. It is then detected with a UV detector at 260 nm by the same method as is used for amino acid analysis. The proposed method is fast, simple and cheap and also has good selectivity and sensitivity for the determination of cyanamide in a wide range of biotic and abiotic materials. 相似文献
734.
Yamamoto Y Saigoku T Ohgai T Nishiyama H Itoh K 《Chemical communications (Cambridge, England)》2004,(23):2702-2703
In the presence of catalytic amounts of Cp*RuCl(cod), the cycloaddition of 1,6-diynes with various C-alkynylglycosides proceeded at ambient temperature to afford C-arylglycosides in 46-93% yields. 相似文献
735.
Nariaki Sugiura Yoshihiko Konno 《Annals of the Institute of Statistical Mathematics》1988,40(2):329-341
Let the distributions of X(p×r) and S(p×p) be N(, I
r) and W
p(n, ) respectively and let them be independent. The risk of the improved estimator for || or {ei329-1} based on X and S under entropy loss (=d/|| –log(d/||)–1 or d||–log(d||)–1) is evaluated in terms of incomplete beta function of matrix argument and its derivative. Numerical comparison for the reduction of risk over the best affine equivariant estimator is given.Dedicated to Professor Yukihiro Kodama on his 60th birthday. 相似文献
736.
Takashi Miyagawa Shinsuke Inuki Maho Honda Shinya Nakamura Isao Nakanishi Nobutaka Fujii Shinya Oishi Hiroaki Ohno 《Tetrahedron》2018,74(15):1802-1809
We recently reported a structure-activity relationship study of 4-epi-jaspine B derivatives toward sphingosine kinase (SphK) and identified selective inhibitors of two SphK isoforms. In this study, we designed and synthesized jaspine B regioisomers on the basis of palladium-catalyzed tetrahydrofuran formation and late-stage cross metathesis reactions to investigate the influence of the substitution position of functional groups on SphK inhibition. Evaluation of the jaspine B regioisomers SphK inhibitory activities revealed that several of these compounds exhibited comparable SphK1/2 inhibitory potency to that of 4-epi-jaspine B. 相似文献
737.
da Silva Lilian Mieko de Lima Almeida Dalva Alves Oishi Silvia Sizuka Couto Andrea Boldarini Ferreira Neidenêi Gomes 《Journal of Solid State Electrochemistry》2019,23(6):1871-1885
Journal of Solid State Electrochemistry - Production and characterization of polyaniline/boron-doped diamond/carbon fiber (PAni/diamond/CF) ternary composites are presented in this work, as well as... 相似文献
738.
Yoshio Ando Yoshihiko Maezawa Jun Shimura Kei Kitamura Takashi Matsumoto Keisuke Suzuki 《化学:亚洲杂志》2020,15(6):828-832
For exploring general routes to the pluramycin‐class of antibiotics, including congeners with epoxide‐bearing side chains, syntheses of kidamycinone and its epoxide (epoxykidamycinone) have been achieved. At the stage of the A‐ring cyclization with alkene‐bearing side chain, the desired 6‐endo product was obtained as a major compound, although the corresponding undesired 5‐exo product was also formed. 相似文献
739.
Dr. Junpei Matsuoka Dr. Shinsuke Inuki Yuka Matsuda Dr. Yoichi Miyamoto Mayumi Otani Prof. Dr. Masahiro Oka Prof. Dr. Shinya Oishi Prof. Dr. Hiroaki Ohno 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(49):11150-11157
The total synthesis of dictyodendrins A–F was achieved by using the gold(I)-catalyzed annulation of a conjugated diyne with N-Boc-pyrrole for direct construction of the pyrrolo[2,3-c]carbazole scaffold. Late-stage functionalization of the resulting pyrrolo[2,3-c]carbazole to introduce various substituents provided divergent access to dictyodendrins. Some dictyodendrin analogues exhibited inhibitory activities toward CDK2/CycA2 and GSK3. 相似文献
740.
Yoshihiko Ooka Fumihiko Kanai Shinichiro Okabe Takuya Ueda Ryota Shimofusa Sadahisa Ogasawara Tetsuhiro Chiba Yasunori Sato Masaharu Yoshikawa Osamu Yokosuka 《Magnetic resonance imaging》2013