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排序方式: 共有137条查询结果,搜索用时 31 毫秒
81.
Masood Parvez Kaleem M. Khosa Muhammad Mazhar Saqib Ali Manzar Sohail 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(1):m51-m54
The crystal structures of 3,3‐dimethyl‐3‐(trichlorogermyl)propionic acid, [Ge(C5H9O2)Cl3], 3,3‐dimethyl‐3‐(triphenylgermyl)propionic acid, [Ge(C6H5)3(C5H9O2)], and 3,3‐dimethyl‐3‐(tri‐p‐tolylgermyl)propionic acid, [Ge(C7H7)3(C5H9O2)], have slightly distorted tetrahedral geometries about the Ge atoms. All the structures form dimers via strong O—H·O hydrogen bonds, resulting in eight‐membered rings that can be best described in terms of graph‐set notation (8). 相似文献
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S. Mahmood S. Shahzadi S. Ali M. Mazhar 《Russian Journal of Inorganic Chemistry》2008,53(8):1217-1220
Dimethytin(IV) S(+)-2-(4-isobutylphenyl)propanoate was synthesized and characterized by elemental analysis and IR and variable
temperature NMR spectroscopy. Variable temperature NMR analysis was performed to see the effect of temperature on coordination
geometry of organotin complexes in non-coordinating solvent. Spectral data has shown that temperature change does not alter
the coordination geometry of the complex, and that it remains greater than four at variable temperatures as well as at room
temperature in solution state.
This text was submitted by the authors in English. 相似文献
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Heterobimetallic molecular precursors [Ti4(dmae)6(mu-OH)(mu-O)6Cu6(OAc)9.H2O] (1) and [Zn7(OAc)10(mu-OH)6Cu5(dmae)4Cl4] (2) for the deposition of metal oxide thin films of Cu6Ti4O12 (Cu3TiO4, TiO2) and Cu5Zn7O12 (ZnO, CuO) were prepared by the interaction of Ti(dmae)4 with Cu(OAc)2.2H2O for 1 and tetrameric (N,N-dimethylamino)ethanolatocopper(II) chloride, [(dmae)CuCl]4 [where dmae = (N,N-dimethylamino)ethanolate] with Zn(OAc)2.2H2O (where OAc = acetate) for 2 in dry toluene. Both complexes were characterized by melting point, elemental analysis, Fourier transform IR, fast atom bombardment mass spectrometry, thermal analysis (TGA), and single-crystal X-ray diffraction. TGA and XRD prove that complexes 1 and 2 undergo facile thermal decomposition at 300 and 460 degrees C to form thin films of Cu/Ti and Cu/Zn mixed-metal oxides, respectively. Scanning electron microscopy and XRD of the thin films suggest the formation of impurity-free crystallite mixtures of Cu3TiO4 and TiO2, with average crystallite sizes of 22.2 nm from complex 1 and of ZnO and CuO with average crystallite sizes of 26.1 nm from complex 2. 相似文献
88.
Mazhar Ul-Islam Waleed Ahmad Khattak Muhammad Wajid Ullah Shaukat Khan Joong Kon Park 《Cellulose (London, England)》2014,21(1):433-447
Regenerated bacterial cellulose (RBC) composites with zinc-oxide nanoparticles (ZnO) were prepared using a new strategy for enhanced biomedical applications of BC. Powdered BC was dissolved in N-methylmorpholine-N-oxide, and different concentrations of ZnO nanoparticles were mixed into the BC solution. RBC, RBC-ZnO1 (1 % ZnO) and ZnO-RBC2 (2 % ZnO) nanocomposite films were prepared by casting the solutions through an applicator. FE-SEM images confirmed the structural features and impregnation of the RBC films by nanoparticles. XRD analysis indicated the presence of specific peaks for RBC and ZnO in the composites. The RBC nanocomposites were found to have greatly enhanced thermal, mechanical and biological properties. Specifically, the degradation temperatures were improved from 334 °C for RBC to 339 and 344 °C for RBC-ZnO1 and RBC-ZnO2, respectively. The mechanical strength and Young’s modulus of the composites were also higher than those of pure RBC. The greatly improved antibacterial properties of the RBC-ZnO nanocomposites are the most striking feature of the present study. The bacterial growth inhibition measured for the RBC was zero, but reached up to 34 and 41 mm for RBC-ZnO1 and RBC-ZnO2, respectively. In addition to their antibacterial properties, the RBC-ZnO nanocomposites were found to be nontoxic and biocompatible with impressive cell adhesion capabilities. These RBC-ZnO nanocomposites can be used for different biomedical applications and have the potential for use in bioelectroanalysis. 相似文献
89.
Muhammad Z. Rana Mazhar Mehmood Jamil Ahmad Muhammad Aslam Syed K. Hasanain Sohail Hameed 《Journal of nanoparticle research》2011,13(1):375-384
We report a novel technique for the formation of metal nanoparticles, based on electrolysis of the alcogels containing metal
chlorides. The alcogel was formed from TEOS, water, ethanol, and nickel chloride, and subjected to galvanostatic electrolysis.
This resulted in successful formation of Ni nanoparticles inside the silica gel. Average particle size of FCC Ni lies between
18 and 20 nm. The formation of tetragonal nickel (a sub-oxide of nickel) as well as NiO were also detected by XRD and SAED.
The resistivity measurements showed that the nickel nanoparticles were separated from each other by Ni(O) present between
them. Magnetic studies based on ZFC and FC measurements below room temperature (up to 5 K) and above room temperature (up
to 700 K) were conducted using SQUID and Magnetic TGA, respectively, which showed strong magnetic irreversibility as attributable
to exchange interaction between metallic and oxide phases and mutual interactions among metallic particles in the network
structure. The blocking temperature (~600 K) of the samples was above room temperature. M–H studies based on VSM showed an
increase in magnetic coercivity with the formation of NiO. A magnetic transition associated with tetragonal nickel was seen
at 10 K. 相似文献
90.
Proteomics Approach to Identify Unique Xylem Sap Proteins in Pierce’s Disease-Tolerant Vitis Species
Sheikh M. Basha Hifza Mazhar Hemanth K. N. Vasanthaiah 《Applied biochemistry and biotechnology》2010,160(3):932-944
Pierce’s disease (PD) is a destructive bacterial disease of grapes caused by Xylella fastidiosa which is xylem-confined. The tolerance level to this disease varies among Vitis species. Our research was aimed at identifying unique xylem sap proteins present in PD-tolerant Vitis species. The results showed wide variation in the xylem sap protein composition, where a set of polypeptides with pI between 4.5 and 4.7 and M r of 31 kDa were present in abundant amount in muscadine (Vitis rotundifolia, PD-tolerant), in reduced levels in Florida hybrid bunch (Vitis spp., PD-tolerant) and absent in bunch grapes (Vitis vinifera, PD-susceptible). Liquid chromatography/mass spectrometry/mass spectrometry analysis of these proteins revealed their similarity to β-1, 3-glucanase, peroxidase, and a subunit of oxygen-evolving enhancer protein 1, which are known to play role in defense and oxygen generation. In addition, the amount of free amino acids and soluble sugars was found to be significantly lower in xylem sap of muscadine genotypes compared to V. vinifera genotypes, indicating that the higher nutritional value of bunch grape sap may be more suitable for Xylella growth. These data suggest that the presence of these unique proteins in xylem sap is vital for PD tolerance in muscadine and Florida hybrid bunch grapes. 相似文献