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The optical limiting behavior of C60Ph5Cl, C60Cl6, and C70Cl10 in toluene solution has been measured at 532 nm with nanosecond pulses. The limiting threshold for C60Ph5Cl, C60Cl6, and C70Cl10 were 4, 8, and 8 J/cm2, respectively. The limiting action was strongly influenced by the number of conjugated double bonds and the nature of the ligand. Both lower limiting thresholds and throughputs make these new fullerene derivative compounds good promising candidates for optical limiting materials in the toluene solution. 相似文献
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Kamel Bouallegue Tamara Allaf Colette Besombes Rached Ben Younes Karim Allaf 《Arabian Journal of Chemistry》2019,12(8):2398-2410
Accelerated Solvent Extraction (ASE) and Dynamic Maceration (DM) were used with n-hexane to study the extraction of oil from date seed powders with different particle sizes. The intensification was studied with instant controlled pressure drop (DIC) as texturing pretreatment. DM yields increased from 4.57% to 10.49 ± 0.05% dry–dry basis (ddb) when particle size decreased from 1.4 to 0.2 mm. For coarsely grounded seed powder, ASE oil yields were 11.35 ± 0.05% ddb and 14.15% ddb for untreated and DIC date-seeds, respectively. Optimized DIC pretreatment allowed the smallest particle size powder to get 15.2 ± 0.05% ddb as ASE yields, while the 2-h DM yields increased from 4.67 to 11.62 ± 0.05% ddb for particle size decreased from 1.4 to 0.2 mm, respectively. Fundamental analysis of various powders was achieved through washing–diffusion phenomenological model. DIC texturing implied higher washing stage, with relative starting accessibility %δYs of 70% against 55% for untreated particles. Consequently, the diffusion stage time was dramatically reduced, without great modification of effective diffusivity Deff value. Therefore, DIC ground seeds greatly enhanced the mass transfer mechanism. The evaluation of starting accessibility δYs enables to establish an empirical relationship between δYs and particle diameter δYs = f(D). Finally, DIC texturing did not imply any modification of the lipid profile. 相似文献
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Zidan MD Allaf AW 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2002,58(8):1577-1582
A new route has been devised, leading to the production of phosphorus thiotrihalides, SPX3 where X = F, Br and I by an on-line process using phosphorus thiotrichloride, SPCl3 as starting compound gassed over the following heated salts NaF, KBr and KI at 530, 800 and 440 degrees C, respectively. The products have been characterized by their IR spectra, showing bands with PQR type structure, centered at 985, 762, 744 and 715 cm(-1). These bands are assigned to v1(a1), the S=P stretching fundamental modes of SPF3, SPCl3, SPBr3 and SPI3, respectively. 相似文献