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71.
This work reports on a new class of dopants, benzoic acid and substituted benzoic acids such as 2‐hydroxybenzoic acid, 2‐chlorobenzoic acid, 4‐nitrobenzoic acid, 2‐methoxybenzoic acid, 3‐methylbenzoic acid, 4‐methylbenzoic acid, 3‐aminobenzoic acid and 4‐aminobenzoic acid, for polyaniline. Benzoic acids can be used to dope polyaniline by mixing benzoic acid (or a substituted benzoic acid) with polyaniline in the common solvent 1‐methyl‐2‐pyrrolidone. Properties of benzoic acid doped polyaniline salts are studied using Fourier transform infra‐red, X‐ray diffraction spectroscopy, scanning electron microscopy, thermogravimetric analysis and conductivity measurements. The conductivity of polyaniline‐benzoic acid salt was found to be high (10−2 S/cm) when compared to polyaniline‐substituted benzoic acid salts (10−3–10−5 S/cm). Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
72.
A new rapid decomposition and dissolution method with a mixture of sodium di-hydrogen orthophosphate and di-sodium hydrogen orthophosphate as a novel flux is described. The minerals are fused with (1:1) mixture of the above salts (flux) and the melt is dissolved in distilled water. The solution is diluted to desired volume depending on the instrumental technique used for determination. ICP-OES is used for the determination of Al, Ca, Mg, Cr, V, Si, Fe and Ti without interference from titanium, iron and sodium phosphate (introduced as flux). All the elements except Si and V are also determined by AAS. The use of nitrous oxide–acetylene flame eliminates the depression due to titanium in the measurement of Mg, Mn, Cr and Fe in air–acetylene flame. Synthetic mixture conforming to ilmenite and rutile composition are analyzed by ICP-OES and AAS to check the validity of the method. The results are in good agreement. The proposed method has been applied to natural samples and the results are evaluated against the established decomposition method using potassium bisulphate. Both ICP-OES and AAS yielded comparable results. The R.S.D. of the proposed method in case of ICP-OES varies from 0.5 to 2%, whereas for AAS it varies from 1.5 to 3% for different elements (n = 5). The novelty of the proposed sample decomposition lies in its simplicity, ease and speed of fusion with minimal skills besides being eco-friendly unlike the reported tedious complicated decomposition procedures involving variety of fluxes and lot of hazardous chemicals. 相似文献
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Kiki Adi Kurnia B. Ariwahjoedi M. I. Abdul Mutalib T. Murugesan 《Journal of solution chemistry》2011,40(3):470-480
Densities were determined for binary mixtures containing the protic ionic liquid bis(2-hydroxyethyl)ammonium acetate [BHEAA]
and an alcohol (methanol, ethanol, and 1-propanol) at four different temperatures (293.15, 303.15, 313.15, and 323.15) K and
ambient pressure. Coefficients of thermal expansion and excess molar volumes were calculated from the experimental densities.
The excess molar volumes were fitted using the Redlich-Kister polynomial equation. Negative deviations from ideal behavior
of the excess molar volume were observed for all systems investigated in this study. The results were interpreted in terms
of ion-dipole interactions and structural factors of the ionic liquid and alcohol. It was observed that an increase of the
alcohol carbon chain length led to lower interactions on mixing. 相似文献
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Murugesan S Park TJ Yang H Mousa S Linhardt RJ 《Langmuir : the ACS journal of surfaces and colloids》2006,22(8):3461-3463
Although nanotechnology has provided a rich variety of nanomaterials (1-100 nm) for in vivo medical applications, the blood compatibility of all these nanobiomaterials is still largely unexamined. Here, we report the preparation of blood-compatible carbon nanotubes (CNTs) that potentially represent the building blocks for nanodevices having in vivo applications. Activated partial thromboplastin time (APTT) and thromboelastography (TEG) studies prove that heparinization can significantly enhance the blood compatibility of nanomaterials. 相似文献
79.
Arumugam P Shinozaki SS Wang R Mao G Brock SL 《Chemical communications (Cambridge, England)》2006,(10):1121-1123
A new approach to the generation of nanoparticle arrays in periodic as well as non-periodic fashions has been discovered based on reduction of oxidized nanoscroll/nanoribbon precursors in the transmission electron microscope (carbothermal reduction) or by hydrogen annealing. Arrays consisting of nickel arsenide nanoparticles of size 3-4 nm have been generated. 相似文献
80.
Gounder MK Lin H Stein M Goodin S Bertino JR Kong AN DiPaola RS 《Biomedical chromatography : BMC》2012,26(5):650-654
2‐Deoxyglucose (2‐DG), an analog of glucose, is widely used to interfere with glycolysis in tumor cells and studied as a therapeutic approach in clinical trials. To evaluate the pharmacokinetics of 2‐DG, we describe the development and validation of a sensitive HPLC fluorescent method for the quantitation of 2‐DG in plasma. Plasma samples were deproteinized with methanol and the supernatant was dried at 45°C. The residues were dissolved in methanolic sodium acetate–boric acid solution. 2‐DG and other monosaccharides were derivatized to 2‐aminobenzoic acid derivatives in a single step in the presence of sodium cyanoborohydride at 80°C for 45 min. The analytes were separated on a YMC ODS C18 reversed‐phase column using gradient elution. The excitation and emission wavelengths were set at 360 and 425 nm. The 2‐DG calibration curves were linear over the range of 0.63–300 µg/mL with a limit of detection of 0.5 µg/mL. The assay provided satisfactory intra‐day and inter‐day precision with RSD less than 9.8%, and the accuracy ranged from 86.8 to 110.0%. The HPLC method is reproducible and suitable for the quantitation of 2‐DG in plasma. The method was successfully applied to characterize the pharmacokinetics profile of 2‐DG in patients with advanced solid tumors. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献