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121.
Azobenzene-conjugated mononuclear and dinuclear terpyridyl complexes of Co(II), Co(III), and Fe(II) were synthesized, and their photoisomerization behavior was investigated. Co(II) and Co(III) complexes, [tpyCo(tpy-AB)]X(n) and [(Cotpy)(2)(tpy-AB-tpy)]X(n) (tpy-AB = C(15)N(3)H(10)-C(6)H(4)-N=NC(6)H(5), tpy-AB-tpy = C(15)N(3)H(10)-C(6)H(4)-N=NC(6)H(4)-C(15)N(3)H(10), X = PF(6) or BPh(4)), exhibit trans-to-cis photoisomerization by irradiation at 366 nm, and this behavior is dependent on solvents and counterions. For the Co(II) complexes, BPh(4) salts undergo cis-to-trans isomerization in propylene carbonate by both photoirradiation with visible light (435 nm) and heat, indicating that reversible trans-cis isomerization has occurred. [Co(tpy-AB)(2)](BPh(4))(2) shows a two-step trans-to-cis isomerization process. The trans-cis isomerization behavior of Co(III) complexes was observed only in the solvents with a low donor number such as 1,2-dichloroethane. Fe(II) complexes, [tpyFe(tpy-AB)]X(n) (X = PF(6) or BPh(4)), exhibit slight trans-to-cis photoisomerization due to the energy transfer from the azobenzene moiety to Fe(tpy)(2) moieties. 相似文献
122.
123.
C Danyoshi Y Terao K Achiwa H Okumura T Kurihara A Matsuura F Kobayashi 《Chemical & pharmaceutical bulletin》1989,37(7):1969-1970
Newly synthesized pyrrolidine derivatives inhibited rabbit platelet aggregation induced by platelet activating factor. 相似文献
124.
T. Matsuura H. Kurihara T. Nagahara K. Sasaki 《Journal of Radioanalytical and Nuclear Chemistry》1986,106(3):175-183
Recoiling behaviour of55Cr produced by54Cr/n, /55Cr reaction was studied by choosing solid Cr/acac/3 or its benzene solution as target material and by using rapid separation technique. The approximate retention value /R-value/ of55Cr, defined as the percentage of the activity retained in the benzene phase which was not extracted with an oxalic acid solution, was found to be higher than that of55Cr for practically all experimental runs tested /15 runs/. The ratio (55Cr/51Cr) was 1.115±0.027. 相似文献
125.
Yasuaki Shinohara Humiyuki FujimoriTomohiro Suzuki Mitsunobu Kurihara 《Journal of Computational and Applied Mathematics》2007
In this paper, a boundary value problem for delay differential equations of population dynamics is considered. We obtain approximate solutions by using Chebyshev polynomial series and Newton–Raphson's procedure and give the error estimation. The method of the error estimation has been obtained in an existence theorem proved by a part of the authors. We carry out some numerical experiments by a computer language MATLAB. 相似文献
126.
127.
R. Seki M. Watanabe K. Kurihara 《Journal of Radioanalytical and Nuclear Chemistry》2000,243(2):383-386
The amount of long-lived radioiodine, 129I (half-life 1.57·107 y) in the Japanese environment has been studied by measuring thyroids of humans and animals. The collected samples were thyroids of (1) humans in Ibaraki Prefecture, in Kanto district, the central part of Japan, (2) cattle in Aomori Prefecture, north part of Japan, and (3) wild deer in Chiba Prefecture, in Kanto district. The measured mean isotopic ratio 129I/127I for thyroids of cattle in Aomori Prefecture is 3.5±1.8·10-9. A higher value of 14±5·10-9 has been obtained for thyroids of wild deer in Kanto district. On the other hand, the measured ratio for human thyroids in Kanto district is 1±0.2·10-9. This value is significantly lower than that of cattle thyroids in Aomori and also those reported for human thyroids in Europe and USA. The higher mean ratio for cattle thyroid in Kanto district is possibly explained by the influence of nuclear reprocessing plant. Lower mean ratio for human thyroid might be due to higher dietary intake of algae. 相似文献
128.
Naoki Hayakawa Kazuya Sadamori Shota Tsujimoto Prof. Dr. Miho Hatanaka Prof. Dr. Tomonari Wakabayashi Prof. Dr. Tsukasa Matsuo 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(21):5859-5863
The reaction of the bulky diphosphenes (Rind)P=P(Rind) ( 1 ; Rind=1,1,3,3,5,5,7,7-octa-R-substituted s-hydrindacen-4-yl) with two molecules of N-heterocyclic carbene (NHC; 1,3,4,5-tetramethylimidazol-2-ylidene) resulted in the quantitative formation of the NHC-bound phosphinidenes NHC→P(Rind) ( 2 ), along with the cleavage of the P=P double bond. The reaction times are dependent on the steric size of the Rind groups (11 days for 2 a (R=Et) and 2 h for 2 b (R=Et, Me) at room temperature). The mechanism for the double bond-breaking is proposed to proceed via the formation of the NHC-coordinated, highly polarized diphospehenes 3 as an intermediate. Approach of a second NHC to 3 induces P−P bond cleavage and P−C bond formation, which proceeds through a transition state with a large negative Gibbs energy change to afford the two molecules of 2 , thus being the rate-determining step of the overall reaction with the activation barriers of 80.4 for 2 a and 29.1 kJ mol−1 for 2 b . 相似文献
129.
Hiroshige Ryosuke Goto Satoru Tsunoda Chihiro Ichii Risa Shimizu Shota Otsuka Yuta Makino Kosho Takahashi Hideyo Yokoyama Hideshi 《Journal of inclusion phenomena and macrocyclic chemistry》2022,102(9-10):791-800
Journal of Inclusion Phenomena and Macrocyclic Chemistry - Ketoprofen is a nonsteroidal anti-inflammatory drug used as mohrus tape which causes unwanted photosensitivity due to UV irradiation. In... 相似文献
130.
Hiroyuki Hayashi Shota Katayama Rong Huang Kosuke Kurushima Isao Tanaka 《固体物理学:研究快报》2015,9(3):192-196
Undoped n‐ and p‐type tin monoxide (SnO) films have been selectively fabricated by pulsed laser deposition with a Sn target and careful control of oxygen partial pressure. The films are epitaxially grown in optimal growth conditions on yttria‐stabilized zirconia (YSZ) substrates with out‐of‐plane and in‐plane orientation relationships of (001)SnO//(001)YSZ and [110]SnO//[100]YSZ, respectively. Both Seebeck and Hall measurements show consistent results on the carrier types of the films. The electron Hall mobility is approximately 11 cm2/Vs at room temperature and the carrier activation energy is 0.14 eV for the n‐type film. The growth at increased oxygen partial pressure yields p‐type films, demonstrating the selective fabrication of both n‐ and p‐type SnO films without doping. (© 2015 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) 相似文献