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61.
Alba Montoya Braulio Insuasty Justo Cobo Christopher Glidewell 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(7):677-680
In the title compound, C26H20ClNO3, the quinoline fragment is nearly orthogonal to the adjacent aryl ring, while the rest of the molecular skeleton is close to being planar. The crystal structure contains no hydrogen bonds of any sort, but there are two π–π stacking interactions present. One, involving the quinoline ring, links molecules related by inversion, while the other, involving the two nonfused aryl rings, links molecules related by translation, so together forming a ladder‐type arrangement 相似文献
62.
The applicability of the convolution potential sweep voltammetry to the calculation of hydration equilibrium constants KH for a series of α-dicarbonyl compounds is demonstrated. KH values for glyoxal, methylglyoxal, acetylbenzoyl, 1,2-cyclohexanedione, diacetyl and 3,4-hexanedione are obtained as functions of the temperature. The values of apparent ΔH and ΔS are calculated from these constants. The consistency of the KH values is tested by showing the occurrence of an enthalpy—entropy compensation effect. Hydration reactions are shown to be enthalpy controlled. 相似文献
63.
64.
Valenzuela M.A. Bosch P. Aguilar-Rios G. Montoya A. Schifter I. 《Journal of Sol-Gel Science and Technology》1997,8(1-3):107-110
ZnAl2O4 was prepared by hydrolyzing a mixture of aluminum alkoxide with zinc nitrate dissolved in hexylene glycol and calcining at
800°C. The results are compared with those obtained by wet mixing and coprecipitation. The sol-gel method produces solids
whose surface areas and pore volumes are 100% larger and with a more homogeneous pore size distribution. 相似文献
65.
C. P. Montoya S. Schadmand I. Diószegi D. J. Hofman P. H. Zhang P. Paul 《Zeitschrift für Physik A Hadrons and Nuclei》1991,340(4):371-375
The strength functions fore
+
e
– pair decay of the isoscalar and isovector giant monopole resonances in highly excited nuclei are derived and used in a statistical model calculation of thee
+
e
– pair energy spectrum from compound nuclear decay in110Sn following a fusion evaporation reaction. This result is then compared to thee
+
e
– spectrum derived from internal pair decay of the giant dipole and giant quadrupole resonances. The computation shows that the pair decay from the excited-state GDR dominates the pair spectrum over the region of all giant resonances, exceedingL=0 transitions by at least a factor of ten. We also compute the angular correlations betweene
+ ande
– for theL=0, L=1 andL=2 transitions and estimate their power to discriminate between the various multipolarities.Dedicated to Prof. Dr. P. Kienle on the occasion of his 60th birthday 相似文献
66.
M. Â. de B.C. Menezes C. de V. S. Sabino M. B. Franco G. F. Kastner E. H. Montoya Rossi 《Journal of Radioanalytical and Nuclear Chemistry》2003,257(3):627-632
Since 1995 the k
0 instrumental neutron activation analysis has been applied at Radiochemical Laboratory, CDTN/CNEN, Brazil, by means of TRIGA MARK I IPR-R1 research reactor. At that time , f, and T
n were determined and the most recent determination of these parameters confirmed the great stability of the reactor along these years. In order to verify the efficiency and accuracy of the method, several certified reference materials have been systematically analyzed. Participating in Intercomparison Exercises organized by IAEA has been an important, essential and useful procedure to quality control. CDTN is the only Brazilian Institute to apply the k
0-INAA to determine elements by means of their isotopes through short, medium and long half life using its own nuclear reactor. 相似文献
67.
J. A. Montoya J. M. Dominguez J. Navarrete I. Shifter T. Viveros D. Chadwick K. Zheng 《Journal of Sol-Gel Science and Technology》1994,2(1-3):431-435
Alumina-titania mixed oxides with nominal atomic ratios Al/Ti=25 and 2 have been synthesized by cohydrolysis of Al(OsecBu)3 and Ti(OBu)4. The oxides were amorphous at 500°C, showing only short range order. Ti was incorporated in alumina in a well dispersed way creating a true Al/Ti mixed oxide. The strength of surface acid sites and specific surface areas were increased at the higher Ti content. The TiO2 anatase phase was avoided and rutile was formed directly at 900°C. 相似文献
68.
Acetaldehyde as an Intermediate in the Electroreduction of Carbon Monoxide to Ethanol on Oxide‐Derived Copper
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Erlend Bertheussen Dr. Arnau Verdaguer‐Casadevall Dr. Davide Ravasio Dr. Joseph H. Montoya Daniel B. Trimarco Claudie Roy Dr. Sebastian Meier Prof. Dr. Jürgen Wendland Prof. Dr. Jens K. Nørskov Prof. Dr. Ifan E. L. Stephens Prof. Dr. Ib Chorkendorff 《Angewandte Chemie (International ed. in English)》2016,55(4):1450-1454
Oxide‐derived copper (OD‐Cu) electrodes exhibit unprecedented CO reduction performance towards liquid fuels, producing ethanol and acetate with >50 % Faradaic efficiency at ?0.3 V (vs. RHE). By using static headspace‐gas chromatography for liquid phase analysis, we identify acetaldehyde as a minor product and key intermediate in the electroreduction of CO to ethanol on OD‐Cu electrodes. Acetaldehyde is produced with a Faradaic efficiency of ≈5 % at ?0.33 V (vs. RHE). We show that acetaldehyde forms at low steady‐state concentrations, and that free acetaldehyde is difficult to detect in alkaline solutions using NMR spectroscopy, requiring alternative methods for detection and quantification. Our results represent an important step towards understanding the CO reduction mechanism on OD‐Cu electrodes. 相似文献
69.
R.?G.?Rodríguez?Avenda?oEmail author J.?A.?de?los?Reyes J.?A.?Montoya T.?Viveros 《Journal of Sol-Gel Science and Technology》2005,33(1):133-138
An experimental strategy was developed to obtain mesoporous SiO2-ZrO2 mixed oxides via a sol–gel process, which involved the use of tetraethylorthosilicate (TEOS) and an inorganic Zr-containing salt. The effects of key process parameters on the properties of the materials were investigated, including the choice of Zr(IV) source (zirconium oxychloride or nitrate), the ZrO2 content and the synthesis pressure (i.e. ambient pressure or hydrothermal conditions). The resulting solids were dried, calcined at 500 °C, and characterized by nitrogen physisorption, pyridine chemisorption, 29Si Nuclear Magnetic Resonance and X-ray diffraction. The data revealed that mesoporous materials with very narrow pore diameter distribution were obtained when using the autoclave procedure from both zirconium nitrate and oxychloride salts. The surface areas and pore size distributions were a function of ZrO2 content. Differences in acidity, as determined by pyridine adsorption, were observed depending on the synthesis parameters. 相似文献
70.
Martínez-Palou R Zepeda LG Höpfl H Montoya A Guzmán-Lucero DJ Guzmán J 《Molecular diversity》2005,9(4):361-369
Summary A versatile route to 40-membered library of 2-long alkyl chain substituted benzoazoles (1 and 2) and azole[4,5-b]pyridines (3 and 4) via microwave-assisted combinatorial synthesis was developed. The reactions were carried out in both monomode and multimode microwave
oven. With the latter, all reactions were performed in high-throughput experimental settings consisting of an 8×5 combinatorial
library designed to synthesize 40 compounds. Each step, from the addition of reagents to the recovery of final products, was
automated. The microwave-assisted N-long chain alkylation reactions of 2-alkyl-1H-benzimidazole (1) and 2-alkyl-1H-benzimidazole[4,5-b] pyridines (3) were also studied. 相似文献