http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Showkat, Ali Md,Lee, Kwang-Pill,Gopalan, Anantha Iyengar,Kim, Sang-Ho The Polymer Society of Korea 2007 Macromolecular Research Vol.15 No.6
Water-soluble, chiral conducting, poly(diphenylamine) (PDPA) nanocomposites were synthesized by chemical oxidative polymerization of diphenylamine in the presence of poly(acrylic acid) (PAA) as a template and camphor sulphonic acid (CSA) as the chiral inductor, Composites were formed as stable aqueous dispersions under different experimental conditions, such as DPA to PAA molar ratios, PAA molecular weight, etc. Circular dichroism(CD) spectra of the composites indicated the induction of chirality to PDPA. Compared to simple chiral PANI, the PDPA/PAA/CSA nanocomposites showed a different Cotton effect. The appearance of a CD band in the composite was complimentary to the bisignate, exciton-coupled band in the UV-Visible spectrum. FTIR spectra indicated the intimate mixing of PDPA and PAA.
Md Showkat, Ali,Lee, Kwang-Pill,Iyengar Gopalan, Anantha,Kim, Sang-Ho,Choi, Seong-Ho,Sohn, Sang-Ho Wiley Subscription Services, Inc., A Wiley Company 2006 Journal of applied polymer science Vol.101 No.6
<P>Composites based on poly(diphenyl amine) (PDPA) and multiwall carbon nanotubes (MWNTs) were prepared by chemical oxidative polymerization through two different approaches: in situ polymerization and intimate mixing. In in situ polymerization, DPA was polymerized in the presence of dispersed MWNTs in sulfuric acid medium for different molar composition ratios of MWNT and DPA. Intimate mixing of synthesized PDPA with MWNT was also used for the preparation of PDPA/MWNT composites. Transmission electron microscopy revealed that the diameter of the tubular structure for the composite was 10–20 nm higher than the diameter of pure MWNT. Scanning electron microscopy provided evidence for the differences in the morphology between the MWNTs and the composites. Raman and Fourier transform IR (FTIR) spectroscopy, thermogravimetric analysis, X-ray diffraction, and UV–visible spectroscopy were used to characterize the composites and reveal the differences in the molecular level interactions between the components in the composites. The Raman and FTIR spectral results revealed doping-type molecular interactions and coordinate covalent-type interactions between MWNT and PDPA in the composite prepared by in situ polymerization and intimate mixing, respectively. The backbone structure of PDPA in the composite decomposed at a higher temperature (>340°C) than the pristine PDPA (∼300°C). This behavior also favored the molecular level interactions between MWNT and PDPA in the composite. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3721–3729, 2006</P>
Analysis of Heavy Metal Toxic Ions by Adsorption onto Amino-functionalized Ordered Mesoporous Silica
Showkat, Ali Md,Zhang, Yu-Ping,Kim, Min-Seok,Gopalan, Anantha Iyengar,Reddy, Kakarla Raghava,Lee, Kwang-Pill Korean Chemical Society 2007 Bulletin of the Korean Chemical Society Vol.28 No.11
Ordered mesoporous silica (MCM-41) materials with different textural properties were prepared using alkyl (dodecyl, cetyl, eicosane) trimethyl ammonium bromide (DTAB, CTAB, ETAB, respectively) as structure directing surfactants, functionalized with amine groups and used as adsorbent for the toxic metal ions, Cr (VI), As (V), Pb (II) and Hg (II). Amino functionalization of mesoporous MCM-41 was achieved by cocondensation of N-[3-(trimethoxysilyl)-propyl] aniline with tetraethyl orthosilicate. Adsorption isotherm and adsorption capacity of the amine functionalized materials for Cr (VI), As (V), Pb (II) and Hg (II) ions were followed by inductively coupled plasma mass spectrometry (ICP-MS). Results demonstrate that amine functionalized MCM-41 prepared with ETAB showed higher adsorption capacity for Cr (VI), As (V), Pb (II) and Hg (II) ions in comparison to MCM-41 prepared with CTAB and DTAB. The higher adsorption capacity for MCM-41(ETAB) was correlated with amine content in the material (determined by CHN analysis) and relative decrease in pore volume and pore diameter. X-ray diffraction (XRD) analysis, nitrogen adsorptiondesorption measurements and Fourier Transform infrared spectrometry (FTIR) were used to follow the changes in the textural parameters and surface properties of the mesoporous materials as a result of amine functionalization to correlate with the adsorption characteristics. The adsorption process was found to depend on the pH of the medium.
Determination of Uranyl Nitrate with Several Ligands by Spectrophotometry
Showkat, Ali Md.,Zhang, Yu-Ping,Kim, Min Seok,Kim, Sang-Ho,Choi, Seong-Ho,Lee, Kwang-Pill The Korean Society of Analytical Science 2004 분석과학 Vol.17 No.1
Trace amount of uranyl (II) has been determined spectrophotometrically by measuring the optical density of the light blue yellowish coloured solutions formed by reaction between the metal ion and nicotinohydroxamic acid (NHx) in presence of different secondary ligands in strong isoamyl alcohol alkaline medium. The absorption maxima for both aqueous and extracted systems measured at their respective optimum pH were found to be 360 and 559 nm (DETA), 375 and 358 nm (EDA), 369 and 362 nm (piperidine), 354 and 341 nm (pyridine) and 363 and 336 nm (3 piperidine), 354 and 341 nm (pyridine) and 363 and 336 nm (3 - picoline), respectively at which Beer's law was obeyed. Effect of pH, reagent concentration, order of addition of reagent, time, temperature and solvent media on the absorption spectra have also been studied. Among the different systems studied, the shortest concentration range of uranyl(II) adhering to Beer's Law was 2.4 - 10.5 ppm observed for $UO_2(II)$ - NHx - DETA system in aqueous medium and also for iso amyl alcohol(IAA) extracted $UO_2$ - NHx - pyridine system was 2.4 - 7.8.
Self assembly directed synthesis of tubular conduction polymer inside th channels of MCM-41
Ali Md Showkat,Kwang-Pill Lee,Anantha Iyengar Gopalan,K Raghava Reddy,Sang-Ho Kim,최성호 한국분석과학회 2006 분석과학 Vol.19 No.3
Diphenyl amine (DPA) was polymerized inside the channels of the mesoporous silica (MCM-41). MCM-41 (C) and MCM-41 (D) were prepared with cetyltrimethyl ammonium bromide (CTAB) and dodecyltrimethyl ammonium bromide (DTAB), respectively and used as hosts. Initially, the self assembly of DPA inside the pores of MCM-41 was made in β-naphthalene sulfonic acid (NSA) medium and subsequently poly (diphenylamine), PDPA was formed by oxidative polymerization. N2 adsorption-desorption measurements of PDPA loaded MCM-41 (C) and MCM-41 (D) show variations in pore volume and surface area between them. A tubular form of poly (diphenylamine), PDPA was envisaged to form in the pores of MCM-41 and supported by high resolution transmission microscopy. The presence of PDPA inside the channel of MCM-41 was further confirmed by FTIR spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction.
Self-assembly directed synthesis of tubular conducting polymer inside the channels of MCM-41
Showkat, Ali Md.,Lee, Kwang-Pill,Gopalan, Anantha Iyengar,Reddy, K. Raghava,Kim, Sang-Ho,Choi, Seong-Ho The Korean Society of Analytical Sciences 2006 분석과학 Vol.19 No.3
Diphenyl amine (DPA) was polymerized inside the channels of the mesoporous silica (MCM-41). MCM-41 (C) and MCM-41 (D) were prepared with cetyltrimethyl ammonium bromide (CTAB) and dodecyltrimethyl ammonium bromide (DTAB), respectively and used as hosts. Initially, the self assembly of DPA inside the pores of MCM-41 was made in ${\beta}$-naphthalene sulfonic acid (NSA) medium and subsequently poly (diphenylamine), PDPA was formed by oxidative polymerization. $N_2$ adsorption-desorption measurements of PDPA loaded MCM-41 (C) and MCM-41 (D) show variations in pore volume and surface area between them. A tubular form of poly (diphenylamine), PDPA was envisaged to form in the pores of MCM-41 and supported by high resolution transmission microscopy. The presence of PDPA inside the channel of MCM-41 was further confirmed by FTIR spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction.
Analysis of Heavy Metal Toxic Ions by Adsorption onto Amino-functionalized Ordered Mesoporous Silica
Ali Md Showkat,Yu-Ping Zhang,Min Seok Kim,Anantha Iyengar Gopalan,Kakarla Raghava Reddy,이광필 대한화학회 2007 Bulletin of the Korean Chemical Society Vol.28 No.11
Ordered mesoporous silica (MCM-41) materials with different textural properties were prepared using alkyl (dodecyl, cetyl, eicosane) trimethyl ammonium bromide (DTAB, CTAB, ETAB, respectively) as structure directing surfactants, functionalized with amine groups and used as adsorbent for the toxic metal ions, Cr (VI), As (V), Pb (II) and Hg (II). Amino functionalization of mesoporous MCM-41 was achieved by co-condensation of N-[3-(trimethoxysilyl)-propyl] aniline with tetraethyl orthosilicate. Adsorption isotherm and adsorption capacity of the amine functionalized materials for Cr (VI), As (V), Pb (II) and Hg (II) ions were followed by inductively coupled plasma mass spectrometry (ICP-MS). Results demonstrate that amine functionalized MCM-41 prepared with ETAB showed higher adsorption capacity for Cr (VI), As (V), Pb (II) and Hg (II) ions in comparison to MCM-41 prepared with CTAB and DTAB. The higher adsorption capacity for MCM-41(ETAB) was correlated with amine content in the material (determined by CHN analysis) and relative decrease in pore volume and pore diameter. X-ray diffraction (XRD) analysis, nitrogen adsorption-desorption measurements and Fourier Transform infrared spectrometry (FTIR) were used to follow the changes in the textural parameters and surface properties of the mesoporous materials as a result of amine functionalization to correlate with the adsorption characteristics. The adsorption process was found to depend on the pH of the medium.