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41.
Carolina A. Pinto P. M. Büchler J. Dweck 《Journal of Thermal Analysis and Calorimetry》2007,87(3):715-720
The catalyst
used in fluidized catalytic cracking (FCC) units of refineries after several
recovery cycles in regeneration units, reduces its activity and it is partially
substituted by new catalyst in the process. As it has a high silicon and aluminum
oxides content, the pozzolanic properties of a Brazilian FCC spent residual
catalyst, used in different substitution degrees to cement, were evaluated
by three thermal analysis techniques during the early stages of hydration
of a type II Portland cement. NCDTA curves show in real time that the residual
catalyst, accelerates the stages of cement hydration. TG and DSC curves of
respective pastes after 24 h of hydration evidence the pozzolanic activity
of the waste, respectively, by the lower water mass loss during the dehydroxylation
of the residual calcium hydroxide and by the lower dehydroxylation endothermal
effect. Within the analyzed period, the higher is the cement substitution
degree, the higher is the pozzolanic activity of the residual catalyst. 相似文献
42.
Mixtures of dioctadecyldimethylammonium chloride (DODAC) cationic vesicle dispersions with aqueous micelle solutions of the anionic sodium cholate (NaC) were investigated by differential scanning calorimetry, DSC, turbidity and light scattering. Within the concentration range investigated (constant 1.0 mM DODAC and varying NaC concentration up to 4 mM), vesicle → micelle → aggregate transitions were observed. The turbidity of DODAC/NaC/water depends on time and NaC/DODAB molar concentration ratio R. At equilibrium, turbidity initially decreases smoothly with R to a low value (owing to the vesicle–micelle transition) when R = 0.5–0.8 and then increases steeply to a high value (owing to the micelle–aggregate transition) when R = 0.9–1.0. DSC thermograms exhibit a single and sharp endothermic peak at Tm ≈ 49 °C, characteristic of the melting temperature of neat DODAC vesicles in water. Upon addition of NaC, Tm initially decreases to vanish around R = 0.5, and the main transition peak broadens as R increases. For R > 1.0 two new (endo- and exothermic) peaks appear at lower temperatures indicating the formation of large aggregates since the dispersion is turbid. All samples are non-birefringent. Dynamic light scattering (DLS) data indicate that both DODAC and DODAC/NaC dispersions are highly polydisperse, and that the mean size of the aggregates tends to decrease as R increases. 相似文献
43.
R. D. Sinisterra R. Najjar O. L. Alves P. S. Santos C. A. Alves De Carvalho A. L. Conde Da Silva 《Journal of inclusion phenomena and macrocyclic chemistry》1995,22(2):91-98
The preparation and characterization of the 1:1 inclusion compound of rhodium(II) -methyl cinnamate in -cyclodextrin is reported. Evidence of inclusion was obtained from X-ray powder diffraction results, Raman, IR and UV-Vis spectroscopic studies and thermal analysis. Given the potential antitumor activity of the rhodium(II) carboxylate and its virtual insolubility in water, its inclusion in -cyclodextrin opens the possibility for its transference to the aqueous phase. 相似文献
44.
M. Angeles Díaz-Díez Fernando J. García-Barros Francisco J. Higes-Rolando Alvaro Bernalte-García Cristóbal Valenzuela-Calahorro 《Transition Metal Chemistry》1995,20(4):402-405
Summary Complexes of CuII with 2-(benzylamino)-2-deoxy-d-glycero-d-talo heptonic acid (BnMa) and 2-(benzylamino)-2-deoxy-d-glycero-l-gluco heptonic acid (BnGa) were prepared and characterized by elemental analysis, thermal data, i.r., electronic and e.s.r. spectra, magnetic susceptibility measurements, and X-ray powder diffraction. The metal:ligand stoichiometry of these complexes is 12 and coordination around CuII seems to be octahedral, with the ligands bound through the N atom of the amino group and O atoms of the bridging carboxylate group. 相似文献
45.
The framework of the paper is that of the full Fock space
and the Banach algebraF
which can be viewed as non-commutative analogues of the Hardy spacesH
2 andH
respectively.An inner-outer factorization for any element in
as well as characterization of invertible elements inF
are obtained. We also give a complete characterization of invariant subspaces for the left creation operatorsS
1
,..., S
n
of
. This enables us to show that every weakly (strongly) closed unital subalgebra of {(S
1
,..., S
n
) F
} is reflexive, extending in this way the classical result of Sarason [S]. Some properties of inner and outer functions and many examples are also considered.The first author was supported in part by NSF DMS 93-21369 1991Mathematics Subject Classification. Primary 47D25, Secondary 32A35, 47A67. 相似文献
46.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Alitti J Álvarez G Alves GA Amidi E Amos N Anderson EW Aronson SH Astur R Avery RE Baden A Balamurali V Balderston J Baldin B Bantly J Bartlett JF Bazizi K Bendich J Beri SB Bertram I Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Bischoff A Biswas N Blazey G Blessing S Boehnlein A Bojko NI Borcherding F Borders J Boswell C Brandt A Brock R Bross A Buchholz D Burtovoi VS Butler JM Casey D Castilla-Valdez H 《Physical review letters》1995,75(6):1023-1027
47.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Alitti J Álvarez G Alves GA Amidi E Amos N Anderson EW Aronson SH Astur R Avery RE Baden A Balamurali V Balderston J Baldin B Bantly J Bartlett JF Bazizi K Bendich J Beri SB Bertram I Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Bischoff A Biswas N Blazey G Blessing S Bloom P Boehnlein A Bojko NI Borcherding F Borders J Boswell C Brandt A Brock R Bross A Buchholz D Burtovoi VS Butler JM Casey D Castilla-Valdez H 《Physical review letters》1995,75(8):1456-1461
48.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Alitti J Álvarez G Alves GA Amidi E Amos N Anderson EW Aronson SH Astur R Avery RE Baden A Balamurali V Balderston J Baldin B Bantly J Bartlett JF Bazizi K Bendich J Beri SB Bertram I Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Bischoff A Biswas N Blazey G Blessing S Boehnlein A Bojko NI Borcherding F Borders J Boswell C Brandt A Brock R Bross A Buchholz D Burtovoi VS Butler JM Casey D Castilla-Valdez H 《Physical review letters》1995,75(4):618-623
49.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Alvarez G Alves GA Amos N Anderson EW Antipov Y Aronson SH Astur R Avery RE Baden A Balamurali V Balderston J Baldin B Bantly J Bartlett JF Bazizi K Behnke T Bendich J Beri SB Bezzubov V Bhat PC Bhatnagar V Biswas N Blazey G Blessing S Boehnlein A Borcherding F Borders J Bozko N Brandt A Brock R Bross A Buchholz D Burtovoi V Butler JM Callot OH Castilla-Valdez H Chakraborty D Chekulaev S Chen J Chen L Chen W 《Physical review letters》1994,72(14):2138-2142
50.
Alves GA Amato S Anjos JC Appel JA Astorga J Bracker SB Cremaldi LM Darling CL Dixon RL Errede D Fenker HC Gay C Green DR Halling AM Jedicke R Karchin PE Kwan S Leuking LH Mantsch PM de Mello Neto JR Metheny J Milburn RH de Miranda JM da Motta Filho H Napier A Passmore D Rafatian A dos Reis AC Ross WR Santoro AF Sheaff M Souza MH Spalding WJ Stoughton C Streetman ME Summers DJ Takach SF Wallace A Wu Z 《Physical review D: Particles and fields》1994,49(9):R4317-R4320