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Sean D. Brooks M. F. Mahmood J. A. Donaldson 《Journal of Mathematical Modelling and Algorithms》2004,3(1):19-29
A numerical investigation, based on the split-step Fourier transform algorithm of all optical switching of solitons in a low
birefringent optical fiber is presented. The numerical algorithm is described in detail.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
4.
Latifeh Navidpour Leila Karimi Mohsen Amini Mohssen Vosooghi Abbas Shafiee 《Journal of heterocyclic chemistry》2004,41(2):201-204
Arylation of the readily available 3‐alkythio‐5‐aryl‐1,2,4‐triazoles gave 5‐alkylthio‐1,3‐diaryl‐1,2,4‐triazoles in moderate yield. The structures of the latter were confirmed by NOE and 13C‐NMR. 相似文献
5.
Crystalline phases of Ti(IV) tungstosilicate and Ti(IV) tungstophosphate have been synthesised. The ion-exchange capacities of Ti(IV) tungstosilicate and Ti(IV) tungstophosphate have been reported as 0.44 and 0.80 mequiv./g, respectively. Both materials show monofunctional ion-exchange characteristic and are stable in 0.1 M solutions of HNO3, HCl, H2SO4 and acetone and benzene. Ti(IV) tungstosilicate is found to be more stable thermally than Ti(IV) tungstophosphate (loss in ion-exchange capacity was found as 58 and 80%, respectively for samples heated at 200 degrees C). The Kd values for heavy metals such as Pb, Hg, Cd, Sb, Co, Zn, Ni, Fe, Cr etc. have been reported in demineralised water and two surfactant media by batch processes. Cr3+, Fe3+ and Sn4+ are totally adsorbed on both the materials in demineralised water while a decrease in Kd value with increase in concentration of two surfactants is reported. On the basis of Kd values for metal ions, thirteen binary separations and five ternary separations on Ti(IV) tungstosilicate and thirteen different binary separations and four different ternary separations on Ti(IV) tungstophosphate have been achieved. Separation of methylamine from ethylamine has been done by GC on a column packed with Ti(IV) tungstophosphate. 相似文献
6.
Abbas Shafiee 《Journal of heterocyclic chemistry》1976,13(2):301-304
A method was developed for the synthesis of 5-carbethoxy-4-formyl-1,2,3-thiadiazole (I), its isomer (II); 5-benzoyl-4-formyl-1,2,3-thiadiazole (III), and its isomer (IV). It was demonstrated that although compounds I, III and IV with hydrazine gave 7H-1,2,3-thiadiazolo[4,5-d]-pyridazin-7-one (XXII), 7-phenyl-1,2,3-thiadiazolo[4,5-d]pyridazine (XXIII) and 4-phenyl-1,2,3-thiadiazolo[4,5-d]pyridazine (XXV), respectively; however, compound I gave its corresponding hydrazone (XXIV). 相似文献
7.
Edwards KW Ogg M Bellerive A Britton DI Hyatt ER MacFarlane DB Patel PM Spaan B Sadoff AJ Ammar R Baringer P Bean A Besson D Coppage D Copty N Davis R Hancock N Kelly M Kotov S Kravchenko I Kwak N Lam H Kubota Y Lattery M Momayezi M Nelson JK Patton S Poling R Savinov V Schrenk S Wang R Alam MS Kim IJ Ling Z Mahmood AH O'Neill JJ Severini H Sun CR Wappler F Crawford G Daubenmier CM Fulton R Fujino D Gan KK Honscheid K Kagan H Kass R Lee J Sung M White C Wolf A Zoeller MM Butler F Fu X Nemati B 《Physical review letters》1995,74(17):3331-3335
8.
Reaction of 5-substituted 2-thioxo-1,3-thiaselenoles with ethyl diazoacetate, phenyl azide and ethyl azidoformate afforded 2-substituted ω-carbethoxy-1,4-thiaselenafulvenes (II) , 5-substituted 2-phenylimino-1,3-thiaselenoles (IV) and 5-substituted 2-carbethoxyimino-1,3-thiaselenoles (V) , respectively. The structure of these compounds were confirmed by spectroscopic methods and chemical analysis. 相似文献
9.
The solid state reactions between TiO2 and Na2S2O8 or K2S2O8 have been investigated using TG, DTG, DTA, IR, and X-ray diffraction studies in the range of 20 to 1000°C.It has been shown that TiO2 reacts stoichiometrically (1 : 1) with Na2S2O8 in the range of 160 and 220°C forming the complex sodium monoperoxodisulfato—titanium(IV) as characterized by IR and X-ray analysis. The new complex then decomposes into the reactants above 190°C.An exothermic reaction has been observed between TiO2 and molten K2S2O7 at mole ratio 1:2 respectively and higher, in the range of 280 and 350°C. The IR and X-ray analyses have shown the formation of a complex namely, potassium tetrasulfato titanium(IV) for which the formula and structure have been proposed. This complex decomposes at higher temperatures into K2SO4 and a mixed sulfate of potassium and titanium. The mixed sulfate melts at 620°C and decomposes into K2SO4, TiO2, and the gaseous SO3.On the other hand, Na2S2O8 decomposes in a special mode producing a polymeric product of Na10S9O32. Decomposition of this species occurs after melting at 560°C into Na2SO4 and sulfur oxides. The decomposition reaction has been proved to be catalysed by TiO2 itself. 相似文献
10.
M. Shekarchi F. Ellahiyan T. Akbarzadeh A. Shafiee 《Journal of heterocyclic chemistry》2003,40(3):427-433
Dehydrogenation of ethyl 3‐methyl‐4‐oxo‐4,5,6,7‐tetrahydrobenzofuran‐2‐carboxylate 1 with 2,2′‐azobi‐sisobutyronitrile and N‐bromosuccinimide gave ethyl 4‐hydroxy‐3‐methylbenzofuran‐2‐carboxylate 3 . Reaction of compounds 3–4 with hydrazine hydrate afforded the corresponding hydrazides 5a‐b . The reaction of 5a‐b with aldehydes yielded substituted hydrazones 6a‐l . Compounds 7a‐d were prepared from compounds 6a‐d and bromine in acetic acid. Lead tetraacetate oxidation of compounds 6e‐l afforded substituted oxadiazoles 8e‐l . Selenium dioxide oxidation of 4‐oxo‐4,5,6,7‐tetrahydrobenzofuran semicarbazones 9, 14a and 4‐oxo‐4,5,6,7‐tetrahydrobenzothiophene 14b gave the tricyclic 1,2,3‐selenadiazoles 10, 15a and 15b respectively. Reaction of semicarbazones 9, 14a and 14b with thionyl chloride afforded the corresponding 1,2,3‐thiadiazoles 12, 16a and 16b respectively. 相似文献