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21.
Fawzya I. Elshami Abd El-Motaleb M. Ramadan Mohamed M. Ibrahim Ibrahim M. El-Mehasseb Salih Al-Juaid Shaban Y. Shaban 《应用有机金属化学》2020,34(3):e5437
In quest of antimicrobial and anticancer agents, metformin containing Ni (II) complexes, [Ni (Met)2]Cl·OH ( 1 ) and [Ni (Met)(IDA)] ( 2 ) {Met: metformin, IDA: iminodiacetic acid} were synthesized and X-ray structure of 1 is four-coordinate square planar geometry. Bovine serum albumin (BSA) interaction and binding studies to Met, IDA and their Ni (II) complexes were investigated and showed a strong interaction. A static quenching process was proposed at low concentrations of compounds whereas, combined quenching process was observed for 1 and 2 at higher concentrations. Kinetic stability, affinity and association constants of compounds-BSA were studied using stopped-flow technique and a mechanism was proposed: a fast and reversible step of BSA binding including complex formation and dissociation was proposed; for the second step, a reversible reaction was observed for 1 and 2 whereas, an irreversible reaction with Met and IDA was observed indicating that coordination with nickel ions change the interaction mechanism. Additionally, the antibacterial investigation against both Gram-positive and Gram-negative bacteria showed that all compounds exhibited significant activities. They also show cytotoxicity against HepG2 human liver cancer cell but the half maximal inhibitory concentration (IC50) values obtained for the cell lines were higher in comparison with cisplatin. Although Met-BSA and IDA-BSA are kinetically more stable than that of 1 -BSA and 2 -BSA, 1 -BSA and 2 -BSA showed better antibacterial and cytotoxic activities which is in agreement with the binding constants. 相似文献
22.
In this paper the singularly perturbed initial boundary value problems for the nonlocal reaction diffusion system are considered. Unsing the iteration method and the comparison theorem, the existence, uniqueness and its asymptotic behavior of solution for the problem are studied. 相似文献
23.
We have investigated the superconducting properties of the Bi1.7 Pb0.3Sr2Ca2−xCe
x
Cu3O10+δ system with x=0.00, 0.02, 0.04, 0.08 and 0.1 by X-ray diffraction and magnetic susceptibility. The substitution of Ce for Ca has been found
to drastically change the superconducting properties of the system. X-ray diffraction studies on these compounds indicate
decrease in the c-parameter with increased substitution of Ce at Ca site and volume fraction of high T
c (2 : 2 : 2 : 3) phase decreases and low T
c phase increases. The magnetic susceptibility of this compound shows that the diamagnetic on set superconducting transition
temperature (onset) varies from 109 K to 51 K for x=0.00, 0.02, 0.04, 0.08 and 0.1. These results suggest the possible existence of Ce in a tetravalent state rather than a trivalent
state in this system; that is, Ca2+ → Ce4+ replacement changes the hole carrier concentration. Hole filling is the cause of lowering T
c of the system. 相似文献
24.
25.
In this paper, we establish several inequalities for some differantiable mappings that are connected with the Riemann-Liouville fractional integrals. The analysis used in the proofs is fairly elementar... 相似文献
26.
27.
S Chanda Sarmishtha Bhattacharyya Tumpa Bhattacharjee SS Ghugre Swapan Kumar Basu S Muralithar RP Singh B Mukherjee RK Bhowmik SN Ray 《Pramana》2001,57(1):175-179
The high spin states in N=80 139Pr have been investigated by in-beam γ-spectroscopic techniques following the reaction 130Te (14N, 5n) reaction at E=75 MeV, using a gamma detector array, consisting of seven 23% compton-suppressed high purity germanium detectors and a multiplicity
ball of fourteen bismuth germanate elements. Based on γ-γ coincidence data, the level scheme of 139Pr has been considerably extended up to 7.2 MeV excitation. Tentative spin-parity assignments are done for the newly proposed
levels on the basis of the DCO ratios corresponding to strong gates and the available information from the earlier light ion
experiments. 相似文献
28.
Clover detector has been used as a Compton polarimeter to measure the linear polarization of γ-rays produced in heavy ion
fusion reaction. The polarization sensitivity of the clover detector has been measured over γ-ray energies ranging from 386
to 1368 ke V. The E1 multipolarity of the 1117 keV transition in 99Rh has been established using this polarimeter. This has resulted in the assignment of negative parity to the band head at
3710 keV in 99Rh. 相似文献
29.
Salih S. Al-Juaid Peter B. Hitchcock Julian A. Johnson John F. Nixon 《Journal of organometallic chemistry》1994,480(1-2):45-50
The preparation of novel 1-arsa-3,4-diphospholyl and 3-arsa-1,4-diphospholyl anions of the type (C2tBu2AsP2)− is described. Spectroscopic and structural characterisation of mono-and bi-metallic complexes of these anions are also reported. 相似文献
30.
A Raghava Rao SS Ramana Reddy K Premchand K L Narasimham K Parthasaradhi V Lakshminarayana 《Pramana》1982,18(3):271-278
The values of incoherent scattering functions are determined experimentally for 145 keV gamma rays in elements Au, Ag and
Y at scattering angles 40°, 70° and 100°, using a x-ray gamma coincidence technique. The corresponding theoretical values
are obtained from the tabulations of Hubbellet al, and computed from the models of Jauch and Rohrlich and Shimizuet al. A comparison between the theoretical and experimental results showed that the non-relativistic approach adopted in the theory
of Shimizuet al is inapplicable to the present cases. A gross agreement is noticed between the present experimental results and the other
theoretical values. 相似文献