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81.
Methyl (E)-4,4-dimethyl-5-oxo-2-pentenoate ( 1 , X = O) reacted with 1,2- or 1,3-aminoalcohols 3 to yield oxazolidines 4a-c or tetrahydro-1,3-oxazines 4d,e. The corresponding imino ester 1 (X = NBu-t) also gave 4 on reaction with 3 . Compounds 4 on heating at 230° yielded 4,5-dihydrooxazoles 5a-c or 5,6-dihydro-4H-1,3-oxazines 5d,e along with methyl 4-methyl-3-pentenoate ( 6 ). 相似文献
82.
The system H(+)Na(+) has been studied on Sephadex C-25 and C-50 at two ionic strengths by potentiometry. The data have been fitted by the H?gfeldt three-parameter model. For ionic strength 0.100 M (Na)ClO(4) an excellent fit is obtained with a standard deviation of +/-0.013 for both gels. For ionic strength 0.010 M (Na)ClO(4) a satisfactory fit could only be obtained by excluding the lowest and highest pH-value for each gel. 相似文献
83.
Takeshi Doi You Osada Atsushi MorishigeOkihito Tokunaga Teijiro Miyata Kouichi HirotaMichihiro Nakajima Mikihisa Komiya Kiyonori Miyajima Shigekazu Baba 《Radiation Physics and Chemistry》1993,42(4-6)
According to the basic research performed using a small size reactor at TRCRE of JAERI, the electron beam irradiation process was proved to be very effective for NOx, SO2 and HC removals from flue-gas of municipal waste incinerators. Based on this result, a pilot-plant was constructed for the demonstration of NOx, SO2 and HC removal performance using electron accelerator of maximum energy 0.95 MeV and maximum power 15kW.The pilot-plant was constructed at Matsudo City waste Disposal Center. The flue-gas of 1,000 Nm3/hr is guided from the waste incinerator flue-gas line of 30,000Nm3/hr to the pilot-plant to be processed by spraying Ca(OH)2 slurry or powder and irradiation with high-energy electron beam of the accelerator. NOx, SO2 and HC are removed simultaneously from the flue-gas by the enhanced reaction with Ca (OH)2 under irradiation.A brief explanation of the pilot-plant and preliminary results of the experiments are introduced in this paper. 相似文献
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86.
Abstract— Effects of 8-methoxypsoralen plus near-UV light on the nematode Caenorhabditis elegans were studied as a novel example of photosensitized actions at the individual level. Either the eggs or the worms were illuminated with near-UV light in the presence of 8-methoxypsoralen. The treatment decreased hatchability of the eggs depending on light fluence and concentration of the sensitizer. Inhibition of growth and premature death were observed when the larvae in the second stage were illuminated in the presence of 8-methoxypsoralen. When young adults were treated before the beginning of egg-laying, they grew to lay eggs, but the total number of eggs deposited per hermaphrodite was decreased and the life span was shortened. 相似文献
87.
Kubo Y Sugasaki A Ikeda M Sugiyasu K Sonoda K Ikeda A Takeuchi M Shinkai S 《Organic letters》2002,4(6):925-928
[structure: see text] Porphyrin tetramer 1 was newly designed and synthesized to construct a novel cooperative [60]fullerene (C(60)) binding system. Compound 1 has a p-terphenyl axis, which is expected to act as a scaffold for a guest-binding information transducer. In toluene, 1 can bind 2 equiv of C(60) to produce a 1:2 1/C(60) complex with association constants of 5800 M(-1) (K(1)) and 2000 M(-1) (K(2)). These values are significantly greater than those for control porphyrin dimers such as 2 and 3. 相似文献
88.
Schiff's bases 1 derived from ketones and t-butylamine reacted with diphenyl malonate, diphenyl methyl-malonate and diphenyl phenylmalonate to give 4-hydroxy-2-pyridones 4–6 . Schiff's bases b on reaction with trimethyl methanetricarboxylate afforded 4-hydroxy-3-methoxycarbonyl-2-pyridones 12 . 相似文献
89.
Revisiting thiol-yne chemistry: Selective and efficient monoaddition for block and graft copolymer formation
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Johannes K. Sprafke Jason M. Spruell Kaila M. Mattson Damien Montarnal Alaina J. McGrath Robert Pötzsch Daigo Miyajima Jerry Hu Allegra A. Latimer Brigitte I. Voit Takuzo Aida Craig J. Hawker 《Journal of polymer science. Part A, Polymer chemistry》2015,53(2):319-326
The untapped potential of radical thiol-yne mono-addition chemistry is exploited to overcome the known limitations of thiol-ene chemistry in polymer coupling and block copolymer formation. By careful choice of alkyne, the reaction can selectively lead to the mono-addition product with efficiencies surpassing those achieved by traditional thiol-ene chemistry. This improvement is illustrated by the nearly quantitative synthesis of a variety of diblock and graft copolymers. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 319–326 相似文献
90.
Hideshi Maki Tatsuo Yokota Katsuyoshi Yoshida Tohru Miyajima Hiroyuki Nariai 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1693-1696
Compared with cyclo -triphosphate anions, cyclo -tri- w -imidotriphosphate anions (Figure 1), cP 3 (NH) 3 3 m , form stable complexes with transition metal ions. Two experimental procedures, potentiometry and spectroscopy, have been applied to determine the stability constants of the complexes with Co 2+ , Ni 2+ , and Cu 2+ ions at 25;C and at I = 0.10 (NaClO 4 ). One-to-one (ML) complex formation has been assumed for the analyses. In the presence of sufficiently high concentration of metal ions, the log g 1 values determined by both methods are consistent with each other, whereas the log g 1 value determined by spectroscopy decreases with the decrease in metal ion concentration. This peculiar phenomenon cannot be explained by the presence of additional complexes, that is, ML 2 or M 2 L. One possible reasoning is agglomeration formation of ligand molecules mediated by countercations in aqueous solution. 相似文献