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121.
122.
Soliman Mohamed A. Mohamed Nader M. A. Takamiya Koichi Sekimoto Shun Inagaki Makoto Oki Yuichi Ohtsuki Tsutomu 《Journal of Radioanalytical and Nuclear Chemistry》2020,324(3):1099-1107
Journal of Radioanalytical and Nuclear Chemistry - To assess the capability of Kyoto University Research Reactor to supply the domestic needs of medical isotopes, its neutron flux has been fully... 相似文献
123.
Eiichi Sato Tsutomu Yokozawa Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》1996,34(4):669-672
Polyadditions of 1,4-benzenedithiol (BDT) to bis(alkoxyallene)s, such as 1,4-bis(allenyloxy)xylene (3) and 1,4-bis(allenyloxy) benzene (4) , were carried out in benzene at 25°C by irradiation with a high pressure mercury lamp. Thiol groups were added to the terminal double bonds of the allenyloxy groups selectively to afford polymers containing reactive carbon–carbon double bonds in the main chain, similar to the radical polyadditions using azobis(isobutyronitrile) (AIBN). The molecular weight of the polymer obtained from BDT and 3 was 10 times higher than that of the polymer produced in the radical polyaddition with AIBN; whereas the molecular weight of the polymer from BDT and 4 was similar to that in the radical polyaddition, probably because of poor solubility of 4 and the polymer toward benzene. The geometrical structure of carbon–carbon double bonds in the polymer isomerized from an E to Z structure with reaction time by virtue of both the addition elimination of thiyl radical to the double bonds and the UV irradiation. © 1996 John Wiley & Sons, Inc. 相似文献
124.
125.
Yoshinori Tominaga Yoshihide Shiroshita Tomohiko Kurokawa Hiromi Gotou Yoshiro Matsuda Akira Hosomi 《Journal of heterocyclic chemistry》1989,26(2):477-487
The reaction of 1-ethoxycarbonylmethylpyridinium bromides 5a-k with nitro ketene dithioacetal, 1,1-bis-(methylthio)-2-nitroethylene ( 2 ), in the presence of triethylamine in ethanol gave the desired ethyl 2-methyl-thioindolizine-3-carboxylates 3a-k in good yields, along with ethyl 2-methylthio-1-nitroindolizine-3-carboxyl-ates 4a-d . Deesterification of 3 using sodium hydroxide in methanol followed by treatment with polyphosphoric acid gave the corresponding 2-methylthioindolizines 5a-d in good yields. The desulfurization of 5 with Raney-nickel in ethanol occurs smoothly to give the 1,2,3-unsubstituted indolizines 6a-c (a , parent indolizine; b , 8-methylindolzine; c , 6,8-dimethylindolizine). Similarly, pyrrolo[2,1-a]isoquinoline ( 19 ) was also synthesized. These indolizine and pyrrolo[1,2-a]isoquinoline derivatives were allowed to react with dimethyl acetylene to give the corresponding cycl[3.2.2]azine and benzo[g]cycl[3.2.2]azine derivatives in good results. 相似文献
126.
在粗糙表面上用液晶空间光调制器进行振动测量 总被引:2,自引:2,他引:0
为实现在一段时间内连续实时观测振动物体的全息干涉图形,采用覆盖铝箔的喇叭作为振动物体,利用铝箔原有未经特殊处理表面反射的漫反射光成像,并用光寻址液晶空间光调制器(Liquid crystal-sparial lightmodulator,LC-SLM)作为全息记录载体,来实现振动测量。实验中采用时间平均干涉测量法,得到了不同振动频率下物体的干涉图形。同时在连续改变振动物体的振动频率时,可以清晰地观察到物体振动全息干涉图形的变化过程,即近实时的全息干涉图形。 相似文献
127.
Keiko Takahashi Hiroshi Narita Megumi Oh-Hashi Akihiro Yokoyama Tsutomu Yokozawa 《Journal of inclusion phenomena and macrocyclic chemistry》2004,50(1-2):121-127
A complete assignment of proton resonances for N(N-formyl d-phenylalanyl)-deoxyamino--cyclodextrin (1d) was performed by means of 1D and 2D NMR,1H–^1H-COSY, 1H–^13C-COSY, TOCSYand NOESY spectroscopy. Based on 2D-NMR ROESY and circular dichroism spectroscopy, the conformation of 1d was determined; the phenyl group stays inside the distorted cyclodextrin (CyD) cavity forming a self-inclusion complex, which is almost the same as N(N-formyl l-phenylalanyl)-deoxyamino--CyD (1l). The remarkable diastereomeric difference was observed in the chemical shifts of H(5) and H(6) protons at the narrow rim of the CyD cavity and induced circular dichroism spectra. These results suggest the existence of hydrogen bonds between the hydroxyl group on CyD and the amide groups on the arms, which provides the difference in the molecular recognition properties. 相似文献
128.
129.
A. Nakajima Y. Masuda E. Matsuda Y. Ueda H. Sameshima T. Ikenoue 《Applied magnetic resonance》2011,40(4):535-544
The reaction between 3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (PCAM), which is a blood–brain-barrier (BBB)
permeable stable cyclic nitroxide, and ascorbic acid was examined in a low dissolved oxygen-phosphate buffer (low DO-PB, 0.1 mM
DO) under 8% oxygen in a glove bag or in an ordinal dissolved oxygen-phosphate buffer (ordinal DO-PB, 0.3 mM DO) under 21%
oxygen in an open atmosphere with and without diethylenetriaminepentaacetic acid (DTPA). In PB with DTPA, no difference was
observed between the results in the low DO-PB and those in the ordinal DO-PB. In the ordinal DO-PB without DTPA, the rate
constant of the PCAM decrease was half that in the low DO-PB without DTPA. The present results indicate that high DO and coexisting
transition metal ions caused the oxidation of ascorbic acid, which degraded the PCAM reduction. The stable nitroxide-ascorbic
acid system without DTPA was found to be applicable to an in vitro model for the acute hypoxia ischemia. 相似文献
130.
Wavelet processing and digital interferometric contrast to improve reconstructions from X‐ray Gabor holograms 下载免费PDF全文
Juan C. Aguilar Masaki Misawa Kiyofumi Matsuda Yoshio Suzuki Akihisa Takeuchi Masato Yasumoto 《Journal of synchrotron radiation》2018,25(3):808-817
In this work, the application of an undecimated wavelet transformation together with digital interferometric contrast to improve the resulting reconstructions in a digital hard X‐ray Gabor holographic microscope is shown. Specifically, the starlet transform is used together with digital Zernike contrast. With this contrast, the results show that only a small set of scales from the hologram are, in effect, useful, and it is possible to enhance the details of the reconstruction. 相似文献