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121.
122.
Anjos JC Appel JA Bean A Bracker SB Browder TE Cremaldi LM Duboscq JE Elliot JR Escobar CO Gibney MC Hartner GF Karchin PE Kumar BR Losty MJ Luste GJ Mantsch PM Martin JF McHugh S Menary SR Morrison RJ Nash T Ong P Pinfold J Punkar G Purohit MV Santoro AF Shoup AL Sliwa K Sokoloff MD Souza MH Spalding WJ Streetman ME Stundzia AB Witherell MS 《Physical review D: Particles and fields》1991,43(3):R635-R640
123.
Anjos JC Appel JA Bean A Bracker SB Browder TE Cremaldi LM Duboscq JE Elliott JR Escobar CO Gibney M Hartner GF Karchin PE Kumar BR Losty MJ Luste GJ Mantsch PM Martin JF McHugh S Menary SR Morrison RJ Nash T Pinfold J Punkar G Purohit MV Santoro AF Sliwa K Sokoloff MD Souza MH Spalding WJ Streetman ME Stundia AB Witherell MS 《Physical review D: Particles and fields》1991,43(7):R2063-R2066
124.
Anjos JC Appel JA Bean A Bracker SB Browder TE Cremaldi LM Duboscq JE Elliott JR Escobar CO Gibney MC Hartner GF Karchin PE Kumar BR Losty MJ Luste GJ Mantsch PM Martin JF McHugh S Menary SR Morrison RJ Nash T Pinfold J Punkar G Purohit MV Ross WR Santoro AF Schmidt DM Shoup AL Sliwa K Sokoloff MD Souza MH Spalding WJ Streetman ME Stundia AB Witherell MS 《Physical review D: Particles and fields》1991,44(11):R3371-R3374
125.
Anjos JC Appel JA Bean A Bediaga I Bracker SB Browder TE Cremaldi LM Duboscq JE Elliot JR Escobar CO Gibney MC Hartner GF Karchin PE Kumar BR Lima JG Losty MJ Luste GJ Mantsch PM Martin JF McHugh S Menary SR Morrison RJ Nash T Pinfold J Punkar G Purohit MV Ross WR Santoro AF Sliwa K Sokoloff MD Souza MH Spalding WJ Streetman ME Stundzia AB Witherell MS 《Physical review letters》1992,69(20):2892-2895
126.
Haddad Paula S. Mauro Antonio E. Nogueira Vânia M. Klein Stanlei I. 《Transition Metal Chemistry》2003,28(8):899-904
[M(CO)4(N—N)] reacts with CuCl to give new heterobimetallic metal carbonyls of the type [M(CO)4(N—N)(CuCl)], M = W, Mo; N—N = 2,2-bipyridine (bipy), 1,10-phenanthroline (phen). Reactions of [M(CO)4(N—N)(CuCl)] with NaSCN produced the series of complexes of general formula [M(CO)4(N—N)(CuSCN)]. The i.r. spectral of all the bimetallic carbonyls exhibited the general four (CO) band patterns of the precursors. The u.v.–vis. spectral data for precursors and products showed bands associated with * (nitrogen ligands), dd (intrametal), as well as MLCT d* (nitrogen ligands) and MLCT d *(CO) transitions. The [M(CO)4(N—N)(CuX)] (X = Cl, SCN) emission spectra showed only one band associated with the MLCT transition. The t.g. curves revealed a stepwise loss of CO groups. The initial decomposition temperatures of the [M(CO)4(N—N)(CuX)] series suggest that the bimetallic compounds are indeed thermally less stable than their precursors, and the X-ray data showed the formation of MO3, CuMO4, Cu2O and CuO as final decomposition products, M = W, Mo. The spectroscopic data suggests that the heterobimetallic compounds are polymeric. 相似文献
127.
A. M. Garrido Pedrosa M. J. B. Souza D. M. A. Melo A. S. Araujo 《Journal of Thermal Analysis and Calorimetry》2007,87(2):351-355
The thermo-programmed reduction study of
Pt/WOx–ZrO2 materials
prepared with different tungsten loading were performed by thermogravimetry.
The samples were synthesized by impregnation method and calcined at 600, 700
and 800°C. The characterizations of both un-calcined and calcined materials
were carried out using different techniques: thermal analysis (TG and DTA),
X-ray diffraction (XRD) and thermo-programmed reduction (TPR). TG and DTA
analysis of un-calcined were used to determination of calcination temperatures
of the samples. XRD diffractograms were useful to help us in the determination
of phase presents. TPR profiles showed between three and four events at different
temperatures attributed to platinum reduction and the different stages of
tungsten specie reduction. 相似文献
128.
Summary In the determination of several perhalogenated compounds after gas chromatographic separation on an Apiezon L column, using
a flame ionization detector, all the compounds tested gave linear area-mass plots although the coefficients observed do not
lead to extrapolations which would permit quantitation of perhalogenated compounds for which no standard is available. Of
the compounds tested, dibromodichloromethane, tetrachloroethene and tetrabromoethene gave good linear correlations of area
ratio-mass ratio (using n-decane as the internal standard). Bromotrichloromethane and tetrabromomethane gave continuously
curving area ratio-mass ratio plots which were very reproducible and could be used for graphical interpolation. 相似文献
129.
Abrunhosa F Faria S Gomes P Tomaz I Pessoa JC Andreu D Bastos M 《The journal of physical chemistry. B》2005,109(36):17311-17319
The interaction of two hybrid peptides of cecropin A and melittin [CA(1-8)M(1-18) and CA(1-7)M(2-9)] with liposomes was studied by differential scanning calorimetry (DSC), circular dichroism (CD), and quasi-elastic light scattering (QELS). The study was carried out with large unilamellar vesicles (LUVs) of three different lipid compositions: 1,2-dimyristoil-sn-glycero-3-phosphocholine (DMPC), 1,2-dimyristoyl-sn-glycero-3-phospho-rac-(1-glycerol) (DMPG) and a binary mixture of DMPC/DMPG, in a wide range of peptide-to-lipid (P:L) molar ratios (0 to 1:7). DSC results indicate that, for both peptides, the interaction depends on membrane composition, with very different behavior for zwitterionic and anionic membranes. CD data show that, although the two peptides have different secondary structures in buffer (random coil for CA(1-7)M(2-9) and predominantly beta-sheet for CA(1-8)M(1-18)), they both adopt an alpha-helical structure in the presence of the membranes. Overall, results are compatible with a model involving a strong electrostatic surface interaction between the peptides and the negatively charged liposomes, which gives place to aggregation in the gel phase and precipitation after a threshold peptide concentration. In the case of zwitterionic membranes, a progressive surface coverage with peptide molecules destabilizes the membrane, eventually leading to membrane disruption. Moreover, delicate modulations in behavior were observed depending on the peptide. 相似文献
130.
Aromí G Gamez P Roubeau O Berzal PC Kooijman H Spek AL Driessen WL Reedijk J 《Inorganic chemistry》2002,41(14):3673-3683
The coordination properties of the new polynucleating ligand H(3)L1 (1,3-bis(3-oxo-3-phenylpropionyl)-2-hydroxy-5-methylbenzene) with Mn(II/III) are described. Depending on the solvent used, the reaction of H(3)L1 with Mn(OAc)(2) yields either of the two new multinuclear assemblies [Mn(2)(HL1)(2)(py)(4)] (1) and [Mn(3)(HL1)(3)] (2), as revealed by X-ray crystallography. The structure of 2 is remarkable in that it shows a unique asymmetric triple-stranded helicate. Complexes 1 and 2 can be interconverted by controlling the solvent of the reaction system, and therefore, this ensemble constitutes an interesting externally addressable switch. In the presence of Mn(III)/pyridine, partial degradation of H(3)L1 occurs via oxidative cleavage, and the new complex [Mn(2)(L2)(2)(py)(4)] (3) is formed. The crystal structure of this complex has shown the fully deprotonated form of the new donor H(3)L2 (3-(3-oxo-3-phenylpropionyl)-5-methylsalicylic acid). From the same reaction, the Mn(II) complex 1 is also obtained. A rational synthesis of H(3)L2 is reported, and this has been used to prepare 3 in high yields, directly from its components. Variable-temperature magnetic susceptibility (chi(m)) measurements were performed on complexes 1-3 under a magnetic field of 1 kG. The data for each complex were fit to the appropriate chi(m) vs T theoretical equation, respectively. In 1, the Mn(II) ions are uncoupled, with g = 2.01. The data from 2 were fit by assuming the presence of an exchange coupled Mn(II)...Mn(II) pair next to a magnetically isolated Mn(II) center. The fit gave J = -2.75 cm(-1), g(12) = 1.97, and g(3) = 1.92, respectively. In 3, two models fit the experimental data. In the most satisfactory, the Mn(III) ions are coupled antiferromagnetically with J = -1.48 cm(-1) and g = 1.98 and a term for weak ferromagnetic intermolecular exchange is included with zJ' = 0.39 cm(-1). The other model contemplates the presence of two uncoupled zero field split Mn(III) ions. 相似文献