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91.
92.
Crystallographic report: Polymeric [3‐(triphenylgermyl)‐3‐o‐methoxyphenylpropionato]trimethyltin(IV)
The polymeric chains of [Sn(CH3)3(C28H25O3Ge)]n contain trimethyltin moieties bridging two neighboring 3‐(triphenylgermyl)‐3‐o‐methoxypropionate ligands via carboxyl groups. The germanium atom has a distorted tetrahedral geometry and the tin atom has a distorted trigonal‐bipyramidal geometry, the latter with three methyl groups in the equatorial plane and oxygen atoms defining the axial positions. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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Sadiq‐ur‐Rehman Saqib Ali Masood Parvez M. Mazhar Amin Badshah 《Heteroatom Chemistry》2004,15(5):398-406
The ligand, 3‐(3‐fluorophenyl)‐2‐phenylpropenoic acid, [C15H11FO2] ( I ) was prepared by reacting equimolar amount of phenyl acetic acid with 3‐fluorobenzaldehyde (1:1) using Perkin condensation method. The trimethyltin(IV) carboxylate, [Me3SnO2FH10C15] ( II ) was synthesized by refluxing an equimolar (1:1) mixture of trimethyltin chloride and silver salt of the ligand acid, [C15H10FO2Ag] ( Ia ). The ligand and complex both were characterized by elemental analysis, IR, mass, 1H NMR, and X‐ray crystallographic data. On the basis of 1H NMR data, (2J[117/119Sn, 1H] and C Sn C bond angle), it is concluded that the environment around the tin atom in solution is tetrahedral. The Infrared spectroscopic results showed that trimethyltin(IV) derivative has 5‐coordinated polymeric structure with bridging carboxylate groups in the solid state, which has been confirmed by the X‐ray crystallographic data. The crystal of ligand acid ( I ) is triclinic with space group Pbar1. However, the crystal of the complex ( II ) is monoclinic with space group C2/c. The geometry around the tin atom is distorted trigonal bipyramid with O(1) and O(2) atoms in apical positions. The ligand ( I ) and complex ( II ) were also tested for their biocidal activities. © 2004 Wiley Periodicals, Inc. Heteroatom Chem 15:398–406, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20032 相似文献
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Syed Ghulam Musharraf Shumaila Mazhar Amna Jabbar Siddiqui M. Iqbal Choudhary Atta-ur-Rahman 《Analytica chimica acta》2013
For the comprehensive metabolite profiling of human plasma, sample preparation is a crucial step. In this investigation, we have compared 10 different extraction techniques for metabolite profiling by GC–MS. Six one-dimensional (1D) and four two-dimensional (2D) extraction techniques involving solvent precipitation, molecular weight cut off tube (MWCOT) and solid phase extraction (SPE) by using silica, RP C18, cation and anion were investigated. Pooled samples of 50 Healthy Male Plasma (HMP), 50 Healthy Female Plasma (HFP) and 100 Healthy Pakistani Plasma (HPP) were subjected to these extraction methods for comparison purposes. Metabolites obtained were identified through NIST mass spectral (Wiley registry), METLIN and Fiehn RTL libraries. XCMS Software was used for the detection of metabolic features, retention time correction, alignment, annotation and statistical analysis in each method. 116–34 peaks were detected by various methods and approx 33% of the peaks were characterized in each method. Hierarchical clustering of the 10 extraction methods showed a low similarity index (50.1%) which indicated different chemical nature of metabolites, resulting from different methods. Venn diagram highlights the GC–MS peaks (33–77%) common in various methods. Metabolites which were different in male and female groups were detected using a threshold value of p ≤ 0.0001, q ≤ 0.001 and fold change ≥3 by employing Welch's t-test and identified through METLIN. Results indicated that 2D-C18 and 2D-silica offers a comprehensive metabolite profile in term of reproducibility, number of peaks and difference in metabolite pattern of male and female. 相似文献
97.
Heterobimetallic molecular precursors [Co2(acac)2mu-OH)2Cu4(dmae)4Cl4] (2) and [Ni2(acac)2(mu-OH)2Cu4(dmae)4Cl4] (3) [dmaeH = N,N-dimethylaminoethanol and acac = 2,4-pentanedionate] for the deposition of mixed oxide thin films were prepared by the interaction of tetrameric N,N-dimethylaminoethanolato copper(II) chloride, [Cu(dmae)Cl]4 (1) with M(acac)2.xH2O, [M = Co, Ni] in toluene. Both heterobimetallic cage complexes were characterized by melting point, elemental analysis, FT-IR spectroscopy, mass spectrometry, magnetometery, and single-crystal X-ray diffraction. Complexes 2 and 3 are isostructural and crystallize in the monoclinic space group P21/n. A TGA study shows that both complexes undergo controlled thermal decomposition at 450 degrees C to give mixed metal oxides. Solid-state infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), and X-ray powder diffraction (XRD) analysis were performed to analyze the chemical composition and surface morphology of the deposited oxide thin films. The results obtained indicate the formation of impurity-free crystalline mixed oxide films with particle sizes ranging from 0.55 to 2.0 microm. 相似文献
98.
Shabana Taj M. Ashraf Chaudhry Muhammad Mazhar 《Journal of Radioanalytical and Nuclear Chemistry》2009,281(3):393-403
Potassium iron(III)hexacyanoferrate(II) supported on poly metylmethacrylate has been synthesized and investigated for the
strontium(II) removal from HNO3 and HCl solutions. The ion exchange material characterized by different techniques and found to be stable in 1.0–4.0 M HNO3 solutions, has been used to elaborate different parameters related to ion exchange and sorption processes involved. The data
collected suggested its use to undertake removal of Sr(II) from more acidic active waste solutions. Thus the material synthesized
had been adjudged to present better chances of application for Sr(II) removal as compared to other such materials. 相似文献
99.
Tin oxide (Sn02 ) thin films are deposited by rf-magnetron sputtering and annealed at various temperatures in the range of 100-500 ℃ for 15 min. Raman spectra of the annealed films depict the formation of a small amount of SnO phase in the tetragonal Sn02 matrix, which is verified by x-ray diffraction. The average particle size is found to be about 20-30 nm, as calculated from x-ray peak broadening and SEM images. Various optical parameters such as optical band gap energy, refractive index, optical conductivity, carrier mobility, carrier concentration etc. are determined from the optical transmittance and reflectance data recorded in the wavelength range 250-2500 nm. The results are analyzed and compared with the data in the literature. 相似文献
100.
Rabia Nazir Muhammad Mazhar Muhammad Siddique S. Tajammul Hussain 《Hyperfine Interactions》2009,189(1-3):85-95
Iron nanoparticles of various sizes have been synthesized using the chemical route which involves the preparation of iron bipyridine complexes in presence of different capping agents followed by thermal decomposition at 450°C in inert atmosphere. The bimetallic nanoalloys of Fe with Mg and Pd have also been prepared by following the same route. The resulting nanoparticles have been characterized by EDX-RF, XRD, AFM and 57Fe Mössbauer spectroscopy. The appearance of quadrupole doublets in the Mössbauer spectra of Fe nanoparticles indicates the absence of magnetic interaction and variation in parameters is due to the varying particle size. The Mössbauer spectrum of Fe–Mg2 bimetallic nanoalloy shows two doublets indicating the presence of superparamagnetism. The two doublets can be attributed to change in s-electron density of iron resulting from its two neighboring magnesium atoms. Fe–Pd nanoalloy Mössbauer spectrum is characterized by having a superparamagnetic doublet and a ferromagnetic sextet. 相似文献