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991.
Conclusions Charge separation in solutions of liposomes sensitized by MP at low temperatures and apparently also at 20°C takes place according to a mechanism of two-quantum photoionization of dimeric molecules of the metalloporphyrins.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 277–282, February, 1985. 相似文献
992.
993.
994.
E. R. Peterson 《Research on Chemical Intermediates》1994,20(1):93-96
The chemical industry admits to minimal use of microwave power because of its high capital and operating costs relative to
steam, combustion, electrical, and other traditional sources of energy. Other valid historical and persistent reasons for
their lack of proper use include: a poor conceptual understanding of microwaves by chemical professionals, their unwillingness
to replace existing adequate methods with radically new technology, the infancy of the microwave industrial power supply,
and unfamiliarity of microwave power systems manufacturers with the chemical industry. In years past, the North American chemical
industry had few competitors and profits were generally large. Environmental regulations were few and product quality was
less a concern than production volume. The microwave power industry relied on the government and communications for lucrative
sales. Those days appear over.
Chemical manufacturers must probe every technology to achieve the edge necessary to stay competitive while meeting environmental
stewardship demands. Microwave power has always offered unique advantages in heating materials selectively and/or quickly
to high or preselected temperatures with fast control response. In the cases discussed in this paper, novel applications of
microwave power afford: faster production, a reduction in product contaminants, reduced downtime, reduced waste, product quality
improvements, and better pollution control. 相似文献
995.
996.
997.
Hydrostannation of 2,4-hexadiyne with dibutyltin dihydride gave 1,1-dibutyl-2,5-dimethylstannole, which was converted to 2,5-dimethylstibacymantrene and to bis(2,5-dimethylstibacyclopentadienyl)iron. 相似文献
998.
999.
R. B. Bayatyan B. E. Bayatyan L. A. Saakyan 《Russian Journal of Applied Chemistry》2006,79(11):1849-1852
Liquid-phase oxidation of bromovinyl compounds with the aim to obtain the corresponding α-bromo acids was studied.
Original Russian Text R.B. Bayatyan, B.E. Bayatyan, L.A. Saakyan, 2006, published in Zhurnal Prikladnoi Khimii, 2006, Vol.
79, No. 11, pp. 1870–1873. 相似文献
1000.
S. A. Giller L. A. Sherin' D. É. Zarin' R. A. Zhuk 《Chemistry of Heterocyclic Compounds》1978,14(5):556-561
The corresponding monophosphates, cyclophosphates, and , -diphosphates were obtained by phosphorylation of 1-(1, 4-dihydroxy-2-pentyl) thymine, 1-(1, 3-dihydroxy-2-propyl) uracil, and their derivatives with selective protection of one of the hydroxyl groups. 2-Cyanoethyl phosphate (CEP) in the presence of N, N-dicyclohexylcarbodiimide (DCC), polyphosphoric acid, and pyrophosphoryl chloride were used as phosphorylating agents. The dependence of the yields of the products of phosphorylation of 1-(1, 4-dihydroxy-2-pentyl) thymine with CEP on the ratio of the reacting substances and the reaction time was studied. The monophosphates were cyclized under the influence of DCC. In the case of 1-(1, 3-dihydroxy-2-propyl) uracil 1-phosphate a dimeric phosphate was obtained in addition to a cyclophosphate. The acid hydrolysis of the cyclophosphates was investigated.See [1] for communication V; see [2] for a preliminary communication.Deceased.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 678–683, May, 1978. 相似文献