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Clidinium is a synthetic anticholinergic agent which has been shown in experimental and clinical studies to have an antispasmodic and antisecretory effect on the gastrointestinal tract. Inhibits the muscarinic effects of acetylcholine at neurotransmitter sites after parasympathetic ganglia. It is used to treat peptic ulcer disease and to help relieve stomach or stomach cramps or cramps due to abdominal cramps, diverticulitis, and irritable bowel syndrome. Mononuclear complexes of the manganese(Ⅱ), nickel(Ⅱ) and mercury(Ⅱ) with clidinium bromide drug (C22H26NO3) types [M(C22H25NO3)2(H2O)4] and [Hg(C22H25NO3)2(H2O)2] where M=Mn (Ⅱ) and Ni(Ⅱ), have been synthesized and characterized on the basis of elemental analysis, conductivity measurements, magnetic, electronic, 1H-NMR and infrared spectral studies. The complexes confirm to 1∶2 stoichiometry and are non-electrolytes. The clidinium drug ligand (C22H26NO3) act as a deprotonated monovalent monodentate chelate coordinating through hydroxyl oxygen where IR spectral bands of clidinium bromide shows a band at 3 226 cm-1 assigned to the OH group stretching frequency, this band ν(O-H) stretching vibration motion is disappeared in case of the infrared spectra of the Mn(Ⅱ), Ni(Ⅱ), and Hg(Ⅱ) complexes suggesting the involvement of the oxygen atom of the deprotonated OH group of clidinium ligand in complexation. The band for the ν(C-O) of alcoholic group of clidinium that appears at 1 240 cm-1 has blue shifted after complexity, indicating the participation of the alcoholic group in the coordination . 1H NMR spectrum for clidinium bromide show a singlet peak at 3.65 ppm due to proton of OH group which isn’t observed in the spectrum of mercury(Ⅱ) complex referring to the deprotonation of OH group and participated in the complexation. Based on electronic spectra, IR spectra and magnetic moment measurements; six coordinated octahedral structures have been proposed for the manganese and nickel(Ⅱ) complexes, while mercury(Ⅱ) complex has a four coordinated geometry. Thermogravimetric analyses studies revealed the presence of coordinated water molecules. For instance the X-ray powder diffraction pattern and scanning electronic microscopy for the Hg(Ⅱ) complex deduced that it was isolated in nanostructured with crystallinity form. 相似文献
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Simple Zeros of the Riemann Zeta-Function 总被引:1,自引:0,他引:1
Assuming the Riemann Hypothesis, Montgomery showed by meansof his pair correlation method that at least two-thirds of thezeros of Riemann's zeta-function are simple. Later he and Taylorimproved this to 67.25 percent and, more recently, Cheer andGoldston increased the percentage to 67.2753. Here we proveby a new method that if the Riemann and Generalized LindelöofHypotheses hold, then at least 70.3704 percent of the zerosare simple and at least 84.5679 percent are distinct. Our methoduses mean value estimates for various functions defined by Dirichletseries sampled at the zeros of the Riemann zeta-function. 1991Mathematics Subject Classification: 11M26. 相似文献
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Quantum Zeno and anti-Zeno paradoxes 总被引:1,自引:0,他引:1
Continuous observation of a time independent projection operator is known to prevent change of state (the quantum Zeno paradox).
We discuss the recent result that generic continuous measurement of time dependent projection operators will in fact ensure
change of state: an anti-Zeno paradox. 相似文献
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粉粒体两相流的电容层析成象测量 总被引:4,自引:0,他引:4
粉粒体系统中的固相浓度分布的在线测量是十分困难的问题.电容层析成象技术是一种近年来发展起来的非侵入式快速浓度场测量技术.它不干扰流场,不受流动中颗粒浓度、加速度、不透明等因素的制约.本文讨论其测量原理、应用、近期进展、存在的主要问题及其解决的对策. 相似文献
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ac Conductivity measurements are carried out across the metal to insulator transition in NiAl0.7Cr0.7Fe0.6O4. The low frequency data is analyzed using Summerfield scaling theory for hopping conductivity. The exponent of the scaling
behavior has significantly different values in the conducting and insulating regimes. The hopping frequency and the zero frequency
conductivity are found to increase with temperature, slowly in the metallic regime and rapidly in the insulating regime. 相似文献
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Samy M. El-Megharbel 《Russian Journal of General Chemistry》2016,86(4):975-982
Sulfacetamide complexes of Ag(I), Cu(II), and Cd(II) were synthesized and characterized by the elemental analyses and IR and 1H NMR spectra. Structural assessment revealed two modes of coordination in the sulfacetamide complexes, showing that sulfacetamide reacts as a bidentate ligand and coordinates to Ag(I) and Cd(II) through the amido and sulfonyl oxygens and to Cu(II) through the NH2 nitrogen. Molar conductance measurements in DMSO showed that both the complexes are nonelectrolytes in nature, which allowed they to be assigned the formulas [Ag(SAM-Na)(NO3)H2O)]·3H2O, [Cu(SAM-Na)2(Cl)2], and [Cd(SAM-Na)(Cl)2]·10H2O. The kinetic and thermodynamic parameters of the thermal decomposition reactions of the complexes were estimated from the TG/DTG curves by the Coats–Redfern and Horowitz–Metzeger methods. The surface morphology of sulfacetamide complexes was scanned using X-ray powder diffraction (XRD) and scanning electron microscope (SEM) analyses. 相似文献
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DC magnetization, neutron depolarization and neutron diffraction (with both polarized and unpolarized neutrons) measurements
have been reported for the Co1.1−x
Zn
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Ge0.1Fe1.2O1 spinels with x=0.5, 0.6 and 0.7. Neutron depolarization and neutron diffraction measurements confirm the presence of a long range ferrimagnetic
ordering of the local canted spins in these ferrite samples. The observed features of low field magnetization have been explained
under the framework of thermally activated domain wall movement of ferrimagnetic arrangement of local canted spins. An important
role of magnetic anisotropy (due to the presence of Co2+ ions) in establishing the magnetic ordering and domain kinetics in these ferrites has been observed. 相似文献