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161.
Professor Emeritus Saul A. Basri Asim O. Barut 《International Journal of Theoretical Physics》1995,34(4):493-521
Two different types of particle state models are discussed. In the first type, particles are considered to be dynamically bound systems of a small set of physical constituents. In the second type, particle states are constructed from tensor products of symmetry constituents, i.e., states that are the basis elements of finite irreducible representations of an internal algebra. These states need not represent physical particles. We present three models of the first type. For the second type, we discuss in detail the main thrust of this paper, a new version of the quark-lepton model based on the algebrasu(4)flaourXsu(6)flavour. The quark color-triplet and a lepton color-singlet are united by a single irreducible representation of su(4)colour. Thesu(6)colour algebra is an extension of the originalsu(3)flavor. All observed ground-state hadron multiplets are in full accord with the predictions of this model. The numbers of hadron ground states it predicts are 36 spin-0 mesons, 36 spin-1 mesons, 70 spin-1/2 baryons, and 56 spin-3/2 baryons.Professor Barut passed away suddenly on December 5, 1994. 相似文献
162.
The solubilities of water in each of the three binary mixtures benzene-carbon tetrachloride, benzene-cyclohexane, and carbon tetrachloride-cyclohexane were determined as a function of solvent composition at 25°C. It was found that, as with the pure solvents, water in the 0.50 mole fraction binary mixtures of these solvents obeyed Henry's law up to saturation. The experimentally determined solubilities were converted to Henry's law constants of water for the entire range of solvent compositions. These values for the Henry's law constants were compared with theoretically calculated values. The comparisons indicated that water in the benzene-cyclohexane and in the benzene-carbon tetrachloride mixtures was preferentially solvated by benzene. Preferential solvation of water was not indicated for the carbon tetrachloride-cyclohexane mixtures. 相似文献
163.
Kaziev G. Z. Quinones Saul O. Bel'skii V. K. Zavodnik V. I. Osminkina I. V. De Ita Antonio 《Russian Journal of Coordination Chemistry》2002,28(6):384-388
Isostructural crystals of aluminum hexamolybdenocobaltate(III) and hexamolybdenocromate(III) Al[MMo6O18(OH)6] · 16H2O (M = Co(III) and Cr(III)) were studied using X-ray diffraction analysis. These compounds crystallize in the triclinic system: space group P
, Z = 1, (calcd) = 2.665 and 2.611 g/cm3, respectively. The unit cell parameters were determined: for aluminum hexamolybdenocobaltate(III), a = 6.796(1) Å, b= 11.248(2) Å, c = 11.568(2) Å; = 101.36(2)°, = 96.95(2)°, = 102.23(2)°; for aluminum hexamolybdenocromate(III), a = 6.838(1) Å, b = 11.312(2) Å, c = 11.605(2) Å; = 101.29(3)°, = 97.13(3)°, = 102.15(3)°. 相似文献
164.
The 14N nuclear quadrupole interaction tensor PN measured by ENDOR in Cu(II) doped l-alanine is analyzed in terms of the Townes and Dailey theory assuming a tetrahedrally bonded N atom. The results of this analysis are compared with those for the 14N in pure l-alanine and it is found that the principal directions of the PN tensor are drastically changed upon metal complexation as a consequence of the higher electron affinity of Cu(II) with respect to C and H. Comparison of the corresponding bond populations in pure and Cu(II) doped l-alanine indicates that the Cu draws 0.11 more electron from the N than the substituted H atom. 相似文献
165.
Isopiestic vapor pressure measurements have been used to determine the osmotic coefficients of aqueous solutions of iodic acid at molalities from 0.1 to 17 mole-kg?1 at 25°C. The isopiestic standards were solutions of sodium chloride and solutions of sulfuric acid. Because of the corrosive nature of iodic acid, platinum cups were used. Stoichiometric activity cofficients of iodic acid were derived by a Gibbs-Duhem integration. The activity coefficients for solutions of molality greater than 0.5 mole-kg?1 cannot be accounted for in terms of the two equilibria, namely, the acidic dissociation of iodic acid and formation of the ion H(IO3) 2 ? , shown by Pethybridge and Prue to explain adequately the behavior in dilute solutions. The activity coefficient is unexpectedly small in concentrated solutions, suggesting the formation of neutral aggregates of iodic acid. The presence of dimers and tetramers, or alternatively trimers and tetramers, can explain the observed results up to a molality of 7 mole-kg?1. 相似文献
166.
Saul Goldman 《Journal of solution chemistry》1977,6(7):461-474
The Variational theory of mixtures due to Mansoori and Leland is modified to account for translational quantum effects in solution, and this modified form of the theory is applied to the problem of gas solubilities in liquids. The theory is used to derive expressions for the Henry's law constant, the molar heat of solution at infinite dilution, and the partial molar volume at infinite dilution for a solute in a liquid solution. These expressions are applied, over a range of temperatures, to the following systems; H2 in each of Ar, N2, and CH4; He in each of Ar, N2, and CH4; and Ne in each of Ar and N2. Lennard-Jones 6–12 pair potentials are used for these calculations. The Lennard-Jones parameters are taken from gas-phase second virial coefficient data. The results obtained are compared with experimental data and with previous calculations on these systems based on the Leonard-Henderson-Barker theory. The variational results appear to be in better agreement with experiment for the He-containing systems, while the Leonard-Henderson-Barker theory seems better for the other systems. An explanation for this is suggested. 相似文献
167.
Ashton C. Lai Dr. Momar Toure Dr. Doris Hellerschmied Jemilat Salami Dr. Saul Jaime‐Figueroa Dr. Eunhwa Ko Dr. John Hines Prof. Craig M. Crews 《Angewandte Chemie (International ed. in English)》2016,55(2):807-810
Proteolysis Targeting Chimera (PROTAC) technology is a rapidly emerging alternative therapeutic strategy with the potential to address many of the challenges currently faced in modern drug development programs. PROTAC technology employs small molecules that recruit target proteins for ubiquitination and removal by the proteasome. The synthesis of PROTAC compounds that mediate the degradation of c‐ABL and BCR‐ABL by recruiting either Cereblon or Von Hippel Lindau E3 ligases is reported. During the course of their development, we discovered that the capacity of a PROTAC to induce degradation involves more than just target binding: the identity of the inhibitor warhead and the recruited E3 ligase largely determine the degradation profiles of the compounds; thus, as a starting point for PROTAC development, both the target ligand and the recruited E3 ligase should be varied to rapidly generate a PROTAC with the desired degradation profile. 相似文献
168.
169.
Adora G. Graham Dr. Saul H. Lapidus Casey G. Hawkins Prof. Peter W. Stephens Prof. Joel S. Miller 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(67):15565-15572
The reactions of MnII(O2CCH3)2 with NEt3Me+CN− and NEt2Me2+CN− form (NEt3Me)2MnII5(CN)12 ( 1 ) and (NEt2Me2)2MnII5(CN)12 ( 2 ), respectively. Structure model-building and Rietveld refinement of high-resolution synchrotron powder diffraction data revealed a cubic [a=24.0093 Å ( 1 ), 23.8804 Å ( 2 )] 3D extended structural motif with adjacent tetrahedral and octahedral MnII sites in a 3:2 ratio. Each tetrahedral MnII site is surrounded by four low-spin octahedral MnII sites, and each octahedral MnII site is surrounded by six high-spin tetrahedral MnII sites; adjacent sites are antiferromagnetically coupled in 3D. Compensation does not occur, and magnetic ordering as a ferrimagnet is observed at Tc=13 K for 2 based on the temperature at which remnant magnetization, Mr(T)→0. The hysteresis has an unusual constricted shape with inflection points around 50 and 1.2 kOe with a 5 K coercivity of 16 Oe and remnant magnetization, Mr, of 2050 emuOe mol−1. The unusual structure and stoichiometry are attributed to the very ionic nature of the high-spin N-bonded MnII ion, which enables the maximization of the attractive van der Waals interactions through minimization of void space via a reduced ∠ MnNC. This results in an additional example of the AxMnIIy(CN)x+2y (x=0, y=1; x=1, y=3; x=2, y=1; x=2, y=2; x=2, y=3; x=3, y=5; and x=4, y=1) family of compounds possessing an unprecedented stoichiometry and lattice motif that are cation adaptive structured materials. 相似文献