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81.
Ismail Warad Maha Al-Ali Belkheir Hammouti Taibi Ben Hadda Rami Shareiah Mohamed Rzaigui 《Research on Chemical Intermediates》2013,39(6):2451-2461
A novel di-μ-chloro-bis[chloro(4,7-dimethyl-1,10-phenanthroline)cadmium(II)] dimer complex has been prepared by reacting CdCl2·2.5H2O with 4,7-dimethyl-1,10-phenanthroline (dmphen) ligand. The complex was characterized on the basis of elemental analysis, FAB-MS, IR, UV–visible, 1H, and 13C NMR spectroscopy, TG/DTA, and X-ray single-crystal diffraction studies. The Cd(II) ions in [CdCl2(C14H12N2)]2 are coordinated to three Cl atoms with the centrosymmetric dimer bridged through the Cl atoms and two N atoms in a slightly distorted square-pyramidal disposition. Several hydrogen bonds formed between the terminal Cl atoms and H-Me/H-Ph groups may stabilize the structure in the dimer form. 相似文献
82.
E. Rajanarendar P. Ramesh E. Kalyan Rao A. Siva Rami Reddy 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2555-2564
Isoxazolyl chloroacetamides (2) were obtained from 4-amino-3-methyl-5-styrylisoxazoles (1) on reaction with chloroacetyl chloride. Cyclocondensation of 2 with NH4SCN yielded 2([-methyl-5-(E)-2-aryl-1-ethenyl]-4-isoxazolylimino)-1,3-thiazolan-4-ones(3). Mannich reaction of 3 with formaldehyde and secondary amines gave isoxazolyl thiazolidinone Mannich bases (4 and 5). 相似文献
83.
Rami A. Abdel-Rahem Martin Reger Matthias Hloucha Heinz Hoffmann 《Journal of Dispersion Science and Technology》2014,35(1):64-75
Aqueous solutions containing sodium lauryl ether sulphate (SLES) and cocamidopropyl Betaine (CAPB) with a constant total surfactant concentration (10 wt%) but different volume mixing ratios were prepared. A remarkable increase in the solutions’ viscosity at a volume mixing ratio of 34 v/v% SLES to 66 v/v% CAPB was observed. By increasing the volume ratio of SLES (r-value) in the binary mixture, the viscosity of 10 wt% SLES, which is close to that of water, increases to a maximum, but then drops down drastically at high r values (>45 v/v%). The maximum viscosity (Vmax) is 2.8 Pas, whereas the minimum is 2 mPas. The rheological behavior at Vmax has the remarkable feature of a simple Maxwell fluid over a large frequency range with one relaxation time. By adding a microemulsion (Plantasil Micro), the value of Vmax decreases extremely, whereas adding cosurfactants like isodecyltrietheleneoxide (IT3) or salts, like calcium chloride, leads to a pronounced increase in the value of Vmax. At 0.76 wt% CaCl2, Vmax is 140 Pas and 150 Pas in the presence of 1 wt% IT3. By increasing the SLES volume mixing ratio in the solution the maximum viscosity is shifted to higher CaCl2 amounts. The increasing viscosity can be explained by a transformation of the micelle shape from spherical to rod-like. Whereas adding cosurfactants or salts leads to an increased entanglement between the rod-like micelles. Consequently, higher microemulsion amounts can be added before reaching the minimum viscosity. 相似文献
84.
Haritha Meruvu Sri Rami Reddy Donthireddy 《Applied biochemistry and biotechnology》2014,172(1):196-205
The purpose of the research was to study the purification and partial characterization of antifungal alkaline chitinase from a newly isolated Citrobacter freundii haritD11. The enzyme was purified in a three-step procedure involving ammonium sulfate precipitation, dialysis, and Sephadex G-100 gel filtration chromatography. The enzyme was shown to have a relative high molecular weight of 64 kDa by sodium dodecyl sulfate polyacrylamide gel electrophoresis and was purified 7.3-fold with a yield of 18.8 %. It was most active at 35 °C, pH 8.0, with colloid chitin as substrate and was very stable at alkaline pH contradicting the characteristic that most of the bacterial chitinases are active at acidic pH. Further, the purified chitinase exhibited remarkable antifungal activity against pathogenic fungi Aspergillus flavus MTCC 2798 and Aspergillus niger MTCC 9652 showing diametric inhibition zones of 27 mm and 21 mm, respectively. 相似文献
85.
R. J. Charity R. Freifelder A. Gobbi N. Herrmann K. D. Hildenbrand F. Rami H. Stelzer J. P. Wessels G. Casini P. R. Maurenzig A. Olmi A. A. Stefanini J. Galin D. Guerreau U. Jahnke A. Péghaire J. C. Adloff B. Bilwes R. Bilwes G. Rudolf M. Petrovici M. Gnirs D. Pelte 《Zeitschrift für Physik A Hadrons and Nuclei》1991,341(1):53-73
Events with 2, 3 and 4 heavy-fragments (A≧20) have been detected in the reactions100Mo+100Mo atE/A =18.7, 23.7 MeV and120Sn+120Sn atE/A=18.4 MeV. The experiments were performed with an array of 12 detectors which together covered a large fraction of the forward hemisphere and allowed a high detection efficiency for these events. Masses and energies of all fragments have been reconstructed by means of an improved version of the kinematic coincidence method. The probabilitiesP 3 andP 4 of producing 3- and 4-body events were found to depend mainly on the dissipated energy rather than on the bombarding energy, thus indicating that their origin lies more in the decay properties of the excited fragments than in the dynamics of the interaction. Emission of light particles from the composite system is shown to become more relevant with increasing bombarding energy and may explain the drop of theP 3 andP 4 curves at high energy losses. Small deviations of theP 3 andP 4 curves at 23.7A · MeV from those at lower bombarding energies were used to estimate the amount of a possible pre-equilibrium light particle emission as a function of impact parameter. 相似文献
86.
This paper studies a stochastic linear quadratic (LQ) control problem in the infinite time horizon with Markovian jumps in parameter values. In contrast to the deterministic case, the cost weighting matrices of the state and control are allowed to be indinifite here. When the generator matrix of the jump process – which is assumed to be a Markov chain – is known and time-invariant, the well-posedness of the indefinite stochastic LQ problem is shown to be equivalent to the solvability of a system of coupled generalized algebraic Riccati equations (CGAREs) that involves equality and inequality constraints. To analyze the CGAREs, linear matrix inequalities (LMIs) are utilized, and the equivalence between the feasibility of the LMIs and the solvability of the CGAREs is established. Finally, an LMI-based algorithm is devised to slove the CGAREs via a semidefinite programming, and numerical results are presented to illustrate the proposed algorithm. 相似文献
87.
Vellarkad N. Viswanadhan M. Rami Reddy Russell J. Bacquet Mark D. Erion 《Journal of computational chemistry》1993,14(9):1019-1026
Estimating log P (logarithm of “1-octanol to water” partition coefficients) as a measure of lipophilicity for organic compounds is of considerable importance in drug discovery. Several methods have been developed for this purpose, each with its own drawbacks and advantages. In this article, a systematic comparison of three well-documented and fully computerized methods has been attempted for a set of nucleosides and bases. The first method (BLOGP) is based on overall molecular properties derived from a molecular orbital calculation to predict log P. The second method (CLOGP) uses fragmental lipophilicity constants with correction factors and treats log P as an additive-constitutive property. The third method (ALOGP) is based on an additivity scheme of atomic lipophilicity constants, with the constitutive factor governed by an elaborate list of atom types. However, none of these methods take into account conformational flexibility or intramolecular hydrogen bonding, which can cause substantial discrepancy between observations and predictions. A comparison of predictions from each of these methods indicates that the atomic contribution method (ALOGP with r = 0.842 and SD = 0.51) is better than other methods (with r = 0.395 and SD = 1.2 for BLOGP and r = 0.713 and SD = 0.93 for CLOGP) for this class of compounds. Our overall assessment is that we do not have, as yet, a highly reliable, fully computerized log P prediction method applicable to flexible heterocycles such as nucleoside analogs. © John Wiley & Sons, Inc. 相似文献
88.
We present a self-contained exposition of the basic aspects of simple theories while developing the fundamentals of forking
calculus. We expound also the deeper aspects of S. Shelah's 1980 paper Simple unstable theories. The concept of weak dividing has been replaced with that of forking. The exposition is from a contemporary perspective and
takes into account contributions due to S. Buechler, E. Hrushovski, B. Kim, O. Lessmann, S. Shelah and A. Pillay.
Received: 12 November 1999 / Revised version: 1 June 2001 / Published online: 12 July 2002 相似文献
89.
F. Rami A. Fahli J. P. Coffin G. Guillaume B. Heusch F. Jundt P. Wagner P. Fintz S. Kox Y. Schutz M. C. Mermaz 《Zeitschrift für Physik A Hadrons and Nuclei》1987,327(2):207-216
The projectile-like fragments emitted in the40Ar +68Zn reaction performed at 14.6, 19.6, 27.6 and 35 MeV/nucleon are studied. Their energy spectra and angular distributions have been measured. Velocities, widths of the linear momentum distributions and cross sections have been deduced. The results are discussedi) in terms of transfer of a few nucleons and analysed with a diffractional model. They are consistent, for stripping reactions, with a direct transfer of nucleons and a target excitation yielding multiparticlemultihole configurations,ii) In terms of projectile fragmentation-like process with a modified abrasion model taking into account the energy separation of the participant nucleons. The projectile fragmentation-like process appears above 20 MeV/nucleon and strongly competes with transfer of nucleons at 35 MeV/nucleon. The evolution of the mechanisms with incident energy is discussed on the basis of the reduced widths of the linear momentum distributions and on those of velocities and cross sections. 相似文献
90.