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  • Author or Editor: Yun Wang x
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Abstract  

The kinetics of bovine serum albumin (BSA) denaturation in the absence and the presence of urea was studied by the iso-conversional method and the master plots method using differential scanning calorimetry (DSC). The observed denaturation process was irreversible and approximately conformed to the simple order reaction, and the denaturation did not follow rigorously first-order kinetic model or other integral order reaction models. The denaturation temperature (T m), apparent activation energy (E a), approximate order of reaction (n), and pre-exponential factor (A) all distinctly decreased as the 2 mol L−1 urea was added, which indicated that the urea accelerated the denaturation process of BSA and greatly reduced thermal and kinetic stability of BSA. This study also demonstrated that the iso-conversional method, in combination with the master plots method, provides a valuable and useful approach to the study of the kinetic process of protein denaturation.

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The impact of financial crisis has resulted in the global economic depression. It is merely cultural industry that acts in a diametrically opposite way so businesses related to cultural industry are still growing. For this reason, this study tends to explore the innovation activities in cultural parks in Taiwan, from the aspect of cultural value. Nevertheless, research on cultural parks in Taiwan still focuses on architecture design and reuse of space; studies on Service Innovation are rather few. This study therefore aims to discuss Service Innovation in cultural parks themselves. With questionnaire survey, the data are further analyzed and discussed. The research findings show 1. significantly positive correlations between Service Innovation and Product Price in Customer Satisfaction, 2. partially positive correlations between Service Innovation and Service Efficiency in Customer Satisfaction, 3. remarkably positive correlations between Service Innovation and Perceived Value in Customer Satisfaction, and 4. notable effects of Customer Characteristics on the correlations between Service Innovation and Customer Satisfaction. The research results are expected to be the reference and contribution to cultural park managers.

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Abstract

USPTO patent data covering the years 1994–2008 is used in this study to examine the citation networks of electronic-paper display technology. Our primary aim is to provide a better understanding of the ways in which emerging firms interact with, and learn from, technology diffusers. Two implications can be drawn from our analysis. Firstly, emerging firms within an emerging industry can enhance their technological capabilities through positive external learning activity. Secondly, despite the fact that technology diffusers have clear technological advantages, with the emergence of a new field, their influence within the network could potentially be decayed if they fail to remain proactive in terms of the absorption of available external knowledge.

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Abstract  

137mBa has been applied successfully to dynamic studies for diagnosis in nuclear medicine for a long time. A variety of inorganic exchangers have been employed for the separation of137mBa from its parent137Cs. In the present study, cupric cobaltic ferrocyanide and amorphous zirconyl phosphate were synthesized and compared for use in a137Cs/137mBa generator. The results show that the former can adsorb137Cs more efficiently and provide high elution yield of137mBa with greater than 99.99% radionuclide purity. A new generator involving multimillicuries of137mBa, in connection with a computerized detection system, has been constructed.

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A high-performance liquid chromatography—diode-array detection method was developed and validated to determine simultaneously eleven major alkaloids in Corydalis decumbens (Thunb.) Pers. The alkaloids detected were corlumidine, protopine, coptisine, tetrahydrojatrorrhizine, palmatine, berberine, sanguinarine, papaverine hydrochloride, tetrahydropalmatine, bicuculline, and corydaline. Chromatographic separation was achieved using a C-18 column with a mobile phase composed of A (0.2% acetic acid solution, adjusted with triethylamine to pH 5.0) and B (acetonitrile), with stepwise gradient elution. Ultraviolet diode-array detection was used; chromatograms were examined at the wavelength of 280 nm. The regression equations showed a good linear relationship between the peak area of each marker and concentration (r = 0.9994–0.9999). The recovery values ranged between 93.66% and 100.54%. The method was fully validated with respect to detection and quantification limits, precision, reproducibility, and accuracy. The described high-performance liquid chromatography (HPLC) method was successfully used for the differentiation and quantification of the eleven major alkaloids in C. decumbens (Thunb.) Pers. and can be considered an effective procedure for the analyses of this important class of natural compounds.

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Abstract  

A chemical process for the separation of147Nd/147Pm from fission products of synthetic radioactive waste solution has been developed. The process includes: (1) denitration, (2) removal of high concentration of uranium by 30% TBP/kerosene extraction, (3) removal of95Nb,103Ru,137Cs and part of90Sr by 50% TBP/dodecane extraction, (4) separation of147Nd/147Pm from part of90Sr and95Zr by oxalic acid precipitation, and (5) removal of144Ce by mixture of 0.4M D2EHPA and 0.2M TBP extraction. Experimental results indicate that the recovery of147Nd/147Pm in the final separated solution is about 90%. The purification of147Nd and147Pm from some other rare earth elements, viz.153Sm,154Eu and144Ce was further investigated by using a Dowex 50W×8 ion-exchanger. Parameters of flow rate, eluent concentration and pH were examined. The results show that the recovery and radionuclide purity of147Nd plus147Pm under the present separation conditions are 77.8% and 98.6% for diethylenetriaminepentaacetic acid (DTPA) and 87.3% and 99.5% for nitrilotriacetic acid (NTA), respectively.

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Abstract

The stability of the inclusion complex of β-CD with cinnamic aldehyde was investigated by means of TG and DSC. The mass loss takes place in three stages: dehydration occurs at 50–120°C; dissociation of β-CD·C9H8O proceeds in the range 200–260°C; and decomposition of β-CD begins at 280°C. The kinetics of the dissociation of β-CD·C9H8O was studied by means of thermogravimetry both at constant temperature and with linearly increasing temperature. The results demonstrate that the dissociation of β-CD·C9H8O is dominated by a one-dimensional diffusion process. The activation energyE is 160 kJ mol−1, and the pre-exponential factorA is 5.8×1014 min−1. Scanning electron microscope observations and the results of crystal structure analysis are in good agreement with those of thermogravimetry.

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Abstract

The stability of β-cyclodextrin-cinnamyl alcohol inclusion complex (β-CD·C9H10·8H2O) was investigated using TG and DSC. The mass loss took place in three stages: the dehydration occurred between 50–120°C; the dissociation of β-CD·C9H10O occurred in the range of 210–260°C; and the decomposition of β-CD began at 280°C. The dissociation of β-CD·C9H10O was studied by means of thermogravimetry, and the results showed: the dissociation of β-CD·C9H10O was dominated by a two-dimensional diffusion process (D2). The activation energyE was 161.2 kJ mol−1, the pre-exponential factorA was 4.5×1013 min−1.

Cyclodextrin is able to form inclusion complexes with a great variety of guest molecules, and the interesting of studies focussed on the energy binding cyclodextrin and the guest molecule.

In this paper, β-cyclodextrin-cinnamyl alcohol inclusion complex was studied by fluorescence spectrophotometry and infrared absorption spectroscopy, and the results show: the stable energy of inclusion complexes of β-CD with weakly polar guest molecules consists mainly of Van der Waals interaction.

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Abstract  

The ability of hexadecyltrimethylammonium cation pillared bentonite (HDTMA+-bentonite) has been explored for the removal and recovery of thorium from aqueous solutions. The adsorbent was characterized using small-angle X-ray diffraction, high resolution transmission electron microscopy and Fourier transform infrared spectroscopy. The influences of different experimental parameters such as solution pH, initial thorium concentration, contact time and temperature on adsorption were investigated. The HDTMA+-bentonite showed the highest thorium sorption capacity at initial pH of 3.5 and contact time of 60 min. Adsorption kinetics was better described by the pseudo-second-order model and adsorption process could be well defined by the Langmuir isotherm. The thermodynamic parameters, ∆G° (298 K), ∆H° and ∆S° were determined to be −31.78, −23.71 kJ/mol and 27.10 J/mol K, respectively, which demonstrated the sorption process of HDTMA+-bentonite towards Th(VI) was feasible, spontaneous and exothermic in nature. The adsorption on HDTMA+-bentonite was more favor than Na-bentonite, in addition the saturated monolayer sorption capacity increased from 17.88 to 31.20 mg/g at 298 K after HDTMA+ pillaring. The adsorbed HDTMA+-bentonite could be effectively regenerated by 0.1 mol/L HCl solution for the removal and recovery of Th(VI). Complete removal (99.9 %) of Th(VI) from 1.0 L industry wastewater containing 16.8 mg Th(VI) ions was possible with 7.0 g HDTMA+-bentonite.

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Abstract  

The ability of hexadecyltrimethylammonium cation pillared bentonite (HDTMA+-bentonite) has been explored for the removal and recovery of uranium from aqueous solutions. The adsorbent was characterized using small-angle X-ray diffraction, high resolution transmission electron microscopy, and Fourier transform infrared spectroscopy. The influences of different experimental parameters such as solution pH, initial uranium concentration, contact time, dosage and temperature on adsorption were investigated. The HDTMA+-bentonite exhibited the highest uranium sorption capacity at initial pH of 6.0 and at 80 min. Adsorption kinetics was better described by the pseudo-second-order model and adsorption process could be well defined by the Langmuir isotherm. The thermodynamic parameters, △ (308 K), Δ, and Δ were determined to be −31.64, −83.84 kJ/mol, and −169.49 J/mol/K, respectively, which demonstrated the sorption process of HDTMA+-bentonite towards U(VI) was feasible, spontaneous, and exothermic in nature. The adsorption on HDTMA+-bentonite was more favor than Na-bentonite, in addition the saturated monolayer sorption capacity increased from 65.02 to 106.38 mg/g at 298 K after HDTMA+ pillaring. Complete removal (≈100%) of U(VI) from 1.0 L simulated nuclear industry wastewater containing 10.0 mg U(VI) ions was possible with 1.5 g HDTMA+-bentonite.

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