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111.
Robin T. Macaluso Satoru Nakatsuji B. Carter Zachary Fisk 《Journal of solid state chemistry》2005,178(11):3547-3553
Single crystals of Ce2PdGa12 have been synthesized in Ga flux and characterized by X-ray diffraction. This compound crystallizes in the tetragonal P4/nbm space group, Z=2 with lattice parameters of and . It shows strongly anisotropic magnetism and orders antiferromagnetically at TN∼11 K. A field-induced metamagnetic transition to the ferromagnetic state is observed below TN. Structure-property relationships with the related heavy-fermion antiferromagnet CePdGa6 are discussed. 相似文献
112.
Rodica
Olar Mihaela Badea Veronica Lazar Carmen Balotescu Elena Cristurean Dana Marinescu 《Journal of Thermal Analysis and Calorimetry》2007,88(2):323-327
N,N-Dimethylbiguanide derivatives (HDMBG)X, where X=CH3COO
(1), Cl (2)
and NO3 (3) respectively,
exhibit in vitro antimicrobial activity
on representative bacterial and fungal strains. The presence of N,N-dimethylbiguanidium
ion for all derivatives was evidenced by IR and 1H
NMR spectra. Thermal analysis gave information on their decomposition steps
and also on the accompanying thermodynamic effects. According to TG and DTG
curves processes as melting, oxidative degradation as well as oxidative condensation
of –C=N– units occur. The different nature of the anions results
different melting points. Paracyanide formation at various condensation degrees
was observed. 相似文献
113.
L.F. Liotta G. Pantaleo A. Macaluso G. Marcì S. Gialanella G. Deganello 《Journal of Sol-Gel Science and Technology》2003,28(1):119-132
Highly dispersed solid solutions of ceria-zirconia with nominal composition Ce0.6Zr0.4O2 were prepared by sol-gel technique and the influence of the gel aging time (1 day–3 weeks) on the morphological and textural properties of the materials was investigated. The samples were calcined at 923 K for 8 h, then characterized by XRD, BET surface area and pore size measurements by gas adsorption and by mercury porosimetry. DTA, TEM and SEM analyses were also carried out. The aging of the gel seems to have a remarkable influence on the morphology of the materials, whose surface area and porosity increase by increasing aging time. The phase composition of the solid solutions of ceria-zirconia, as determined by XRD analysis, seems to be independent from the synthetic procedure; in any case a cubic phase (space group Fm-3m) was identified as the main component. XRD and TEM characterizations show the presence of highly dispersed crystallites, with diameters in the range 60–80 Å. The redox properties and hydrogen chemisorption capacity have been studied by TPR/TPD/TPO experiments. Oxygen storage capacity measurements were carried out by a pulse technique, to determine the overall reducibility of the solid, OSCC (Oxygen storage capacity complete). OBC (Oxygen buffering capacity) measurement were also performed to determine the ability of the ceria-zirconia oxides to attenuate fast oscillations (0.1 Hz) of oxygen partial pressure. The correlation between textural, structural and redox properties of the oxides is discussed. 相似文献
114.
Wibren D. Oosterbaan Veronica E. M. Kaats‐Richters Leonardus W. Jenneskens Cornelis A. Van Walree 《Journal of polymer science. Part A, Polymer chemistry》2004,42(19):4775-4784
Two high molecular weight linear polyesters were investigated to gain insight in how the photophysics of electron donor‐(σ‐spacer)‐electron acceptor (DσA) compounds are affected by incorporation into a polymer. They were prepared by condensation of either adipoyl or sebacoyl chloride with a diol that was functionalized with an N,N‐dialkylaniline donor, a cyclohexyl type σ‐spacer, and a 1,1‐dicyanovinyl acceptor. The solubility, which is very low, and the thermal properties of the polyesters are dictated by physical crosslinking as a consequence of interchain donor‐acceptor interactions. Charge transfer (CT) absorption and emission are observed, which involve CT between DσA moieties of different chains rather than CT processes within a single DσA unit. As a result, the photophysics of the DσA units in the polyesters differs strongly from that of similar DσA compounds in solution. Upon swelling the polymers with THF, the CT fluorescence disappears partly. Analogous polymers containing only an N,N‐dialkylaniline donor display dual fluorescence; one band reflects local emission, while the other is attributed to excimer emission. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4775–4784, 2004 相似文献
115.
116.
Joseph Zaia Veronica M. Bierbaum 《Journal of the American Society for Mass Spectrometry》2018,29(6):1061-1064
117.
118.
Antonino Lauria Annalisa Guarcello Gabriella Macaluso Anna Maria Almerico 《Tetrahedron letters》2009,50(52):7333-1004
The reactivity of asymmetric benzo-condensed diazines in the 1,3-dipolar cycloaddition reactions with nitrilimines was investigated. The results demonstrated that, at variance with the symmetric quinoxaline, a certain grade of diastereoselectivity emerged. Moreover in the case of the 5-methylquinoxaline and quinazoline a mono-cycloadduct was obtained. 相似文献
119.
120.
Dr. Kathrin Junge Veronica Papa Prof. Dr. Matthias Beller 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(1):122-143
Non-noble metal catalysts based on pincer type compounds are of special interest for organometallic chemistry and organic synthesis. Next to iron and manganese, currently cobalt–pincer type complexes are successfully applied in various catalytic reactions. In this review the recent progress in (de)hydrogenation, transfer hydrogenation, hydroboration and hydrosilylation as well as dehydrogenative coupling reactions using cobalt–pincer complexes is summarised. 相似文献