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81.
A novel tetradentate nitrogen donor [N4] macrocyclic ligand, i.e. 1,3,4,8,9,11-hexaaza-2,5,10,12-tetraoxo-7,14-diphenyl-cyclotetradecane (L), has been synthesized. Mn(II), Co(II), Ni(II)
and Cu(II) complexes of this ligand have been prepared and subjected to elemental analyses, molar conductance measurements,
magnetic susceptibility measurements, mass, 1H-n.m.r. (Ligand), i.r., electronic, and e.p.r. spectral studies. On the basis of molar conductance the Mn(II), Co(II) and
Cu(II) complexes may be formulated as [M(L)X2] [where X = Cl− & NO
3
−
] due to their non-electrolytic nature in dimethylformamide (DMF). Whereas the Ni(II) complexes are 1:2 electrolytes and formulated
as [Ni(L)]X2. All the complexes are of the high spin type and are six/four coordinate. On the basis of i.r., electronic and e.p.r. spectral
studies an octahedral geometry has been assigned to Mn(II) and Co(II), square planar for Ni(II) complexes, and tetragonal
for Cu(II) complexes. The antimicrobial activities of the ligand and its complexes, as growth inhibiting agents, have been
screened in vitro against several species of bacteria and plant pathogenic fungi. 相似文献
82.
Chandra S Gupta LK 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2004,60(13):3079-3085
Complexes of Cr(III), Co(II), Ni(II) and Cu(II) containing a novel macrocyclic tetradentate nitrogen donor (N4) ligand prepared via reaction of 2,3-hexanedione and ethylenediamine has been prepared and characterized. The newly synthesized ligand (L) and its complexes have been characterized on the basis of elemental analysis, molar conductance, magnetic moment susceptibility, EI-Mass, IR, Electronic and EPR spectral studies. The complexes are of high-spin type and four coordinated tetrahedral, five coordinated square pyramidal and six coordinated octahedral/tetragonal geometries. The ligand (L) and its soluble transition metal complexes have also been screened against different bacteria and plant pathogenic fungi in vitro. 相似文献
83.
A novel tetradentate nitrogen donor [N4] macrocyclic ligand, i.e. 3,5,13,15,21,22-hexaaza-2,6,12,16-tetramethyl-4,14-dithia-tricyclo[15.3.1.1(7–11)]docosane-1(21),2,5,7,9,11(22),12,15,17,19-decaene,
has been synthesized. Mn(II), Co(II), Ni(II) and Cu(II) complexes with this ligand have been prepared and subjected to elemental
analyses, molar conductance measurements, magnetic susceptibility measurements, mass, 1H-n.m.r. (Ligand), i.r., electronic, and e.p.r. spectral studies. On the basis of molar conductance the complexes may be formulated
as [M(L)X2] and [Ni(L)]X2 [where M = Mn(II), Co(II) and Cu(II), and X = Cl− and NO3−] due to their nonelectrolytic nature in dimethylsulphoxide (DMSO). All the complexes are of the high spin type and are six
coordinated. On the basis of i.r., electronic and e.p.r. spectral studies an octahedral geometry has been assigned to Mn(II)
and Co(II), square planar for Ni(II) complexes, and tetragonal for Cu(II) complexes. The antimicrobial activities of the ligand
and its complexes, as growth inhibiting agents, have been screened in vitro against several species of bacteria and plant pathogenic fungi. 相似文献
84.
85.
Ashish Khaparde S. Lokesh Kumar M. A. Vijayalakshmi Kishore K. R. Tetala 《Electrophoresis》2021,42(24):2647-2655
PDMS-based multichannel microfluidic chip was designed and fabricated in a simple approach using readily available tools. UV-initiated in situ polymerization of poly(2-hydroxy ethyl methacrylate-co-di(ethylene glycol) diacrylate-co-N,Nʹ-diallyl l -tartardiamide) in an Eppendorf tube was achieved within 40 min. This polymerization process was successfully translated to a microfluidic chip format without any further modifications. Iminodiacetic acid was successfully immobilized on aldehyde functional monoliths via Schiff base reaction and confirmed by FT-IR spectroscopy. Four transition metal ions (Co (II), Zn (II), Ni (II), and Cu (II)) were chelated individually on four IDA-monolith microfluidic chips. The conjoint metal-ion monolith microfluidic chip has displayed high permeability (9.40 × 10–13 m2) and a porosity of 32.8%. This affinity microfluidic chip has pre-fractioned four human plasma proteins (fibrinogen, immunoglobulin, transferrin, and human serum albumin) based on their surface-exposed histidine surface topography. A protein recovery of approximately 95% (Bradford assay data) was achieved. The multimonolith microchip can be reusable even after three protein adsorption-desorption cycles. 相似文献
86.
Chandan Bagdia Shamik Bhattacharjee Madhusree Roychowdhury Anuvab Mandal Gregory Lapicki Lokesh C. Tribedi 《X射线光谱测定》2020,49(1):160-164
The experimental measurement of total electron transfer cross section in Bragg peak energy region is important to understand energy loss in the biomolecular system. In this study, we have measured state selective, K-K electron capture and K-ionization cross sections for adenine (C 5H 5N 5) in collisions with fast (2.5–5 MeV/u) C ions. These are compared with the data for smaller gas molecule, CO 2. These are derived from a study of the KLL-Auger electron emission yields as a function projectile charge state. The K-ionization cross-section (σKI) data are compared with the ECUSAR (united and separated atom [USA] approximation with energy loss [E], Coulomb deflection [C], and relativistic [R] corrections) model calculation. The measured σKI data and the calculations are in good agreement. The K-K transfer cross-section (σK−K) data are compared with the CPSSR (perturbed stationary state [PSS] with Coulomb deflection [C] and relativistic corrections [R]) calculation that underestimates the measured data for such symmetric collision system. The energy dependence of σK−K for adenine is found to be flat in contrast to a sharp variation predicted by the model. The K-transfer cross section is found to be substantial fraction of the K-ionization. 相似文献
87.
Bianchi type I string dust cosmological models in the presence and absence of magnetic field in the frame work of Lyra geometry are investigated. To get the deterministic model of the universe, we assume that the eigenvalue (σ11 ) of shear tensor (σi j ) is proportional to expansion (θ ). This leads to A =(BC)n, where A, B, C are metric potentials and n is a constant. To discuss the results in terms of cosmic time t, we have considered n = 1. The physical and geometrical aspects of the models and singularities in the models are also discussed. 相似文献
88.
Lokesh Pawar Ramesh Jayaramaiah Baburaj Krishnan Athimoolam Arunachalampillai Ying Chen Andrew T. Parsons Jo Anna Robinson Jason S. Tedrow 《Tetrahedron》2019,75(32):4266-4270
The development of a phase-appropriate manufacturing-scale synthesis of potassium 2-fluoro-6-hydroxyphenyltrifluoroborate was achieved. Investigations into improving the yield and robustness indicated that pH of the reaction medium is a critical process parameter. Additional development resulted in replacing tartaric acid with citric acid, resulting in improved process robustness and enabling scale-up to >10 kg. 相似文献
89.
Nandarapu Kumarswamyreddy Kanduru Lokesh Venkitasamy Kesavan 《Tetrahedron letters》2018,59(49):4344-4348
3-Alkynyl-3-OBoc oxindoles underwent Cu(II) mediated Friedel-Crafts alkylation with indoles and phenols to yield of structurally diverse 3-alkynyl-3-indole/phenol-oxindole derivatives. The synthetic application of alkylated phenol derivatives were further demonstrated to biologically important new class of chromene fused spirooxindoles through intramolecular metal-free iodocyclization under mild reaction conditions with broad substrate scope in very good yields. 相似文献
90.
Unified gas kinetic scheme combined with Cartesian grid method for intermediate Mach numbers
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We develop a method to seamlessly simulate flows over a wide range of Knudsen numbers past arbitrarily shaped immersed boundaries. To achieve seamless computation, ie, not use any zone division to distinguish between continuum and non‐continuum regions, we use the unified gas kinetic scheme (UGKS), which is based on the Bhatnagar‐Groos‐Krook (BGK) approximation of the Boltzmann equation. We combine UGKS with an appropriately designed Cartesian grid method (CGM) to allow us to compute flows past arbitrary boundaries. The CGM we use here satisfies boundary conditions at the wall by using a constrained least square interpolation procedure. However, it differs from the usual, continuum CGMs in 2 ways. Firstly, to allow us capture non‐continuum effects at the boundaries, the CGM used herein interpolates the microscopic velocity distribution function in addition to the macroscopic variables. Secondly, even for the macroscopic variables, we use a gas kinetic method–based density interpolation procedure at the boundaries that allows the CGM to interface well with the UGKS method. We demonstrate the robustness and efficacy of the method by testing it on stationary immersed boundaries at various Knudsen numbers ranging from continuum to transition regimes. 相似文献