A quantitative Fourier transform infrared (FTIR) technique mas established by comparison with chemical analysis and quantitative X-ray diffraction (XRD) analysis. By the quantitative FTIR analysis of bauxite during di...A quantitative Fourier transform infrared (FTIR) technique mas established by comparison with chemical analysis and quantitative X-ray diffraction (XRD) analysis. By the quantitative FTIR analysis of bauxite during dissolution , the process of dissolution and precipitation of silica was found to occur in three stages. In the first stage, there was no precipitation of desilication product (DSP). All the silica dissolved from kaolinite went into the solution. In the second stage, the silica concentration in solution attained a maximum and then dropped very quickly. The precipitation of DSP was the main cause of the reduction of the silica concentration in solution. In the third stage, the concentration of DSP reached a constant level. The dissolution and precipitation process gradually attained an equilibrium. The mechanism of silica dissolution and DSP precipitation was discussed on the basis of the FTIR quantitative analysis of kaolinite and DSP in bauxite.展开更多
Structure of the duplex consisting of 23 pairs of bases was studied before and after the methylation of two cytosine molecules from different chains of the duplex. The study was performed in a buffer solution using an...Structure of the duplex consisting of 23 pairs of bases was studied before and after the methylation of two cytosine molecules from different chains of the duplex. The study was performed in a buffer solution using an IR Fourier spectrometer. The absorption bands corresponding to the duplex backbone were found to change their characteristics after the methylation. Firstly, the integrated intensity ratio of the absorption bands, S1044/S1085, decreased by a factor of 1.5. The absorption band at 1044 cm-1 corresponds to the COC bond of deoxyribose, and the band at 1085 cm-1 to the PO2symm.vibr bond. Secondly, a substantial shift of the absorption band 1085→1112 cm-1 (Δν = 27 cm-1) was observed. In addition, pronounced changes in the absorption region of CH stretching vibrations took place. In particular, shifting of some absorption bands assigned to the stretching vibrations of CH bonds;the 2979→2945.7 shift was equal to 33.3 cm-1. In addition to the indicated changes, some bands corresponding to the Z structure appeared in the methylated duplex. Thus, methylation of two cytosine molecules in the duplex leads to the order→order structural transition, most likely to the B→Z transition.展开更多
The study was useful for the treatment of Reactive red 223 (R223) and Coomassie brilliant blue R250 (CBBR250) binary dye system by electrocoagulation process (EC). Moreover, the Al and Fe electrode were used as an ano...The study was useful for the treatment of Reactive red 223 (R223) and Coomassie brilliant blue R250 (CBBR250) binary dye system by electrocoagulation process (EC). Moreover, the Al and Fe electrode were used as an anode and cathode, respectively. The response surface methodology (RSM) was adopted by utilizing central composite design to plan the experimental runs. The EC process was preceded under the effect of operating parameters including pH, NaCl, voltage and electrolysis time. The % color and COD removals were examined as response variables. The removal efficiency of RR223 and CBBR250 dye at optimum values was 89% and 94% and COD removal was 100%. The kinetic study was performed to determine the rate and rate constant. First and second order kinetic models were studied to figure out the exact mechanism of the dye removal using EC process. The estimated cost of the experimental design about 4.486 US$/dm3 was also determined. This study showed that EC process is an economical way for the treatment of waste water.展开更多
FTIR method was used in this paper to investigate the structure of lysozyme in D2O solution and in microemulsions.It was found from the subtraction spectra that the Amide Ⅰband shifts to lower wavenumbers in microemu...FTIR method was used in this paper to investigate the structure of lysozyme in D2O solution and in microemulsions.It was found from the subtraction spectra that the Amide Ⅰband shifts to lower wavenumbers in microemulsions. The assignment of deconvoluted AmideⅠbund was given.The curve-fitting resulte show that the α-helix structure of lysozyme is reduced a lot in microemulsions.展开更多
Objective To decompose and reformulate Banxia Baizhu Tianma Decoction（BBT） in order to optimize its ratio for vasodilatory effect.The fingerprints of these six component herbs were also studied via Tri-step FTIR ana...Objective To decompose and reformulate Banxia Baizhu Tianma Decoction（BBT） in order to optimize its ratio for vasodilatory effect.The fingerprints of these six component herbs were also studied via Tri-step FTIR analysis.Methods The herbal components of BBT were extracted separately with different solvents,such as 95%ethanol,50%ethanol,and distilled water.The vasodilatory effect of the extracts was studied using the in vitro pre-contracted aortic ring model.Among these extracts,the water extracts of Pinellia ternata[PT（W）]and Citri reticulatae[CR（W）],50%ethanol extracts of Castrodia elata[GE（50）]and Clycyrrhiza uralensis[GU（50）],and 95%ethanol extracts of Atractylodes macrocephala[AM（E）],and Poria cocos[PC（E）]were selected for the orthogonal stimulus-response compatibility group study due to their high effectiveness in vasodilation.Results The best combination ratio（G2） was GE（50）,GU（50）,AM（E）,PC（E）,CR（W）,and PT（W） at EC0,EC5,EC5,EC5,EC5,and EC5,with EC50 of（0.06 ± 0.01） mg/mL.Comparison between the vasodilatory effects of extracts derived from G2 and BBT were also studied.From the results,the 50%ethanol extract following G2 ratio was found to be most potent extract with the highest vasodilatory effect compared with other extracts derived from G2 or BBT,with EC50 of（0.05 ±0.005） mg/mL.Conclusion The optimum ratio and appropriate extraction method for the new BBT formulae are obtained.G2 is determined as the best formulae with the highest potency in producing the vasodilatory effect on isolated rat aortic rings.The results obtained suggest that 50%ethanol is found to be the best solvent to extract the vasoactive compounds of G2 in order to exhibit the highest efficacy of vasodilatory effect.展开更多
Details regarding field decomposition and transformation of biochar in Malaysia are scarce. The objectives of this study were to investigate the physico-chemical changes experienced by Jatropha pod biochar (JPB) in ac...Details regarding field decomposition and transformation of biochar in Malaysia are scarce. The objectives of this study were to investigate the physico-chemical changes experienced by Jatropha pod biochar (JPB) in acidic mineral soil under field condition. Elemental composition was determined using CHNS-O analyzer and surface area with Brunauer-Emmett-Teller (BET) method. The JPB surface chemistry and structure were studied using the Fourier Transform Infrared (FTIR) spectroscopy and 13C solid state Nuclear Magnetic Resonance (NMR) spectroscopy, respectively. The JPB short-term decomposition was investigated by using a litter bag study and decomposition data were best fitted by a hyperbolic decay model compared to an exponential decay model because no significant dry weight loss was detected after 4 months. Two phases (volatile and near stagnant) were detected for JPB field decomposition. The volatile phase was due to rapid loss of labile fraction such as carbohydrate during the initial 4 months. The near stagnant phase was probably due to adsorption of organic matter and soil minerals. The JPB was fragmented into smaller pieces, encouraging surface adsorption. Redox reaction was prominent as shown by the production of hydroxyl, carboxylic and phenolic functional groups. The JPB became more recalcitrant after 12 months of application to the soils.展开更多
文摘A quantitative Fourier transform infrared (FTIR) technique mas established by comparison with chemical analysis and quantitative X-ray diffraction (XRD) analysis. By the quantitative FTIR analysis of bauxite during dissolution , the process of dissolution and precipitation of silica was found to occur in three stages. In the first stage, there was no precipitation of desilication product (DSP). All the silica dissolved from kaolinite went into the solution. In the second stage, the silica concentration in solution attained a maximum and then dropped very quickly. The precipitation of DSP was the main cause of the reduction of the silica concentration in solution. In the third stage, the concentration of DSP reached a constant level. The dissolution and precipitation process gradually attained an equilibrium. The mechanism of silica dissolution and DSP precipitation was discussed on the basis of the FTIR quantitative analysis of kaolinite and DSP in bauxite.
文摘Structure of the duplex consisting of 23 pairs of bases was studied before and after the methylation of two cytosine molecules from different chains of the duplex. The study was performed in a buffer solution using an IR Fourier spectrometer. The absorption bands corresponding to the duplex backbone were found to change their characteristics after the methylation. Firstly, the integrated intensity ratio of the absorption bands, S1044/S1085, decreased by a factor of 1.5. The absorption band at 1044 cm-1 corresponds to the COC bond of deoxyribose, and the band at 1085 cm-1 to the PO2symm.vibr bond. Secondly, a substantial shift of the absorption band 1085→1112 cm-1 (Δν = 27 cm-1) was observed. In addition, pronounced changes in the absorption region of CH stretching vibrations took place. In particular, shifting of some absorption bands assigned to the stretching vibrations of CH bonds;the 2979→2945.7 shift was equal to 33.3 cm-1. In addition to the indicated changes, some bands corresponding to the Z structure appeared in the methylated duplex. Thus, methylation of two cytosine molecules in the duplex leads to the order→order structural transition, most likely to the B→Z transition.
文摘The study was useful for the treatment of Reactive red 223 (R223) and Coomassie brilliant blue R250 (CBBR250) binary dye system by electrocoagulation process (EC). Moreover, the Al and Fe electrode were used as an anode and cathode, respectively. The response surface methodology (RSM) was adopted by utilizing central composite design to plan the experimental runs. The EC process was preceded under the effect of operating parameters including pH, NaCl, voltage and electrolysis time. The % color and COD removals were examined as response variables. The removal efficiency of RR223 and CBBR250 dye at optimum values was 89% and 94% and COD removal was 100%. The kinetic study was performed to determine the rate and rate constant. First and second order kinetic models were studied to figure out the exact mechanism of the dye removal using EC process. The estimated cost of the experimental design about 4.486 US$/dm3 was also determined. This study showed that EC process is an economical way for the treatment of waste water.
文摘FTIR method was used in this paper to investigate the structure of lysozyme in D2O solution and in microemulsions.It was found from the subtraction spectra that the Amide Ⅰband shifts to lower wavenumbers in microemulsions. The assignment of deconvoluted AmideⅠbund was given.The curve-fitting resulte show that the α-helix structure of lysozyme is reduced a lot in microemulsions.
基金Exploratory Research Grant Scheme(ERGS)(203/PFARMASI/6730122)Universiti Sains Malaysia-Research University Grants(1001/PFARMASI/812195)
文摘Objective To decompose and reformulate Banxia Baizhu Tianma Decoction（BBT） in order to optimize its ratio for vasodilatory effect.The fingerprints of these six component herbs were also studied via Tri-step FTIR analysis.Methods The herbal components of BBT were extracted separately with different solvents,such as 95%ethanol,50%ethanol,and distilled water.The vasodilatory effect of the extracts was studied using the in vitro pre-contracted aortic ring model.Among these extracts,the water extracts of Pinellia ternata[PT（W）]and Citri reticulatae[CR（W）],50%ethanol extracts of Castrodia elata[GE（50）]and Clycyrrhiza uralensis[GU（50）],and 95%ethanol extracts of Atractylodes macrocephala[AM（E）],and Poria cocos[PC（E）]were selected for the orthogonal stimulus-response compatibility group study due to their high effectiveness in vasodilation.Results The best combination ratio（G2） was GE（50）,GU（50）,AM（E）,PC（E）,CR（W）,and PT（W） at EC0,EC5,EC5,EC5,EC5,and EC5,with EC50 of（0.06 ± 0.01） mg/mL.Comparison between the vasodilatory effects of extracts derived from G2 and BBT were also studied.From the results,the 50%ethanol extract following G2 ratio was found to be most potent extract with the highest vasodilatory effect compared with other extracts derived from G2 or BBT,with EC50 of（0.05 ±0.005） mg/mL.Conclusion The optimum ratio and appropriate extraction method for the new BBT formulae are obtained.G2 is determined as the best formulae with the highest potency in producing the vasodilatory effect on isolated rat aortic rings.The results obtained suggest that 50%ethanol is found to be the best solvent to extract the vasoactive compounds of G2 in order to exhibit the highest efficacy of vasodilatory effect.
文摘Details regarding field decomposition and transformation of biochar in Malaysia are scarce. The objectives of this study were to investigate the physico-chemical changes experienced by Jatropha pod biochar (JPB) in acidic mineral soil under field condition. Elemental composition was determined using CHNS-O analyzer and surface area with Brunauer-Emmett-Teller (BET) method. The JPB surface chemistry and structure were studied using the Fourier Transform Infrared (FTIR) spectroscopy and 13C solid state Nuclear Magnetic Resonance (NMR) spectroscopy, respectively. The JPB short-term decomposition was investigated by using a litter bag study and decomposition data were best fitted by a hyperbolic decay model compared to an exponential decay model because no significant dry weight loss was detected after 4 months. Two phases (volatile and near stagnant) were detected for JPB field decomposition. The volatile phase was due to rapid loss of labile fraction such as carbohydrate during the initial 4 months. The near stagnant phase was probably due to adsorption of organic matter and soil minerals. The JPB was fragmented into smaller pieces, encouraging surface adsorption. Redox reaction was prominent as shown by the production of hydroxyl, carboxylic and phenolic functional groups. The JPB became more recalcitrant after 12 months of application to the soils.
