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1.
Tatiya Khamhangdatepon Vut Tongnan Matthew Hartley Thana Sornchamni Nuchanart Siri-Nguan Navadol Laosiripojana Kang Li Unalome Wetwatana Hartley 《International Journal of Hydrogen Energy》2021,46(48):24666-24675
La0·3Sr0·7Co0·7Fe0·3O3 (LSCF3773) was chosen as an oxygen carrier material for synthesis gas production and synthesized using ethylene-diamine-tetra-acetic acid (EDTA) citrate-complexing method. LSCF exhibited a pure cubic structure where 110 and 100 plane diffractions were active for CO2 splitting, while 111 was more favored by H2O splitting. Overall oxygen storage capacity (OSC) of LSCF was 4072 μmol/gcat. During the reduction process, regular cations (Co4+, Fe4+), polaron cations (Co3+, Fe3+) and localized cations (Co2+, Fe2+) were achieved when the LSCF was reduced at 500, 700 and 900 °C, respectively. The strength of the active sites depended on reduction temperatures. An increase in oxidation temperature enhanced H2 production at temperature ranging from 500 °C to 700 °C while effected CO production at 900 °C. H2O and CO2 was competitively split during the oxidation step, especially at 700 °C. The activation energy of each reaction was ordered as; CO2 splitting > H2O splitting > CO2 adsorption, supporting the above evidence where H2 and CO production were found to increase when the operating temperature was increased. 相似文献
2.
Yu-Mi Lee Byung-Jin Na Yu-Si Lee Shin Young Park Myung-Sub Chung Young-Soo Chang Dong-Ho Lee Sung-Hee Choi Gun-Hee Kim Sang-Do Ha 《Food science and biotechnology》2013,22(3):865-869
This study was conducted to develop an appropriate management strategy for the safe consumption of children’s snacks. In this study, a caffeine content analysis was performed on children’s snacks which were distributed at stores located near to schools. A total of 213 samples (63 chocolates, 40 ice cakes, 19 canned instant coffees, and 91 beverages) were analyzed for caffeine content. The caffeine content of chocolates, ice cakes, canned instant coffees, and beverages was 94.30, 35.03, 391.78, and 68.32 mg/kg, respectively. The results of the exposure assessment for caffeine were expressed as estimated daily intake (EDI) compared to the acceptable daily intake (ADI). The EDI/ADI ratio of the high risk group (95th percentile) for caffeine intake was 7.63–27.13 %. The results of this study indicate that the EDI of caffeine from snacks sold at stores located near to schools is much lower than the ADI in general. Consequently, children’s snacks are thought to be safe for consumption. 相似文献
3.
W. Jamsak P.L. Douglas E. Croiset R. Suwanwarangkul N. Laosiripojana S. Charojrochkul S. Assabumrungrat 《Journal of power sources》2009
Solid oxide fuel cell systems integrated with a distillation column (SOFC-DIS) have been investigated in this study. The MER (maximum energy recovery) network for SOFC-DIS system under the base conditions (CEtOH = 25%, EtOH recovery = 80%, V = 0.7 V, fuel utilization = 80%, TSOFC = 1200 K) yields QCmin = 73.4 and QHmin = 0 kW. To enhance the performance of SOFC-DIS, utilization of internal useful heat sources from within the system (e.g. condenser duty and hot water from the bottom of the distillation column) and a cathode recirculation have been considered in this study. The utilization of condenser duty for preheating the incoming bioethanol and cathode recirculation for SOFC-DIS system were chosen and implemented to the SOFC-DIS (CondBio-CathRec). Different MER designs were investigated. The obtained MER network of CondBio-CathRec configuration shows the lower minimum cold utility (QCmin) of 55.9 kW and total cost index than that of the base case. A heat exchanger loop and utility path were also investigated. It was found that eliminate the high temperature distillate heat exchanger can lower the total cost index. The recommended network is that the hot effluent gas is heat exchanged with the anode heat exchanger, the external reformer, the air heat exchanger, the distillate heat exchanger and the reboiler, respectively. The corresponding performances of this design are 40.8%, 54.3%, 0.221 W cm−2 for overall electrical efficiency, Combine Heat and Power (CHP) efficiency and power density, respectively. The effect of operating conditions on composite curves on the design of heat exchanger network was investigated. The obtained composite curves can be divided into two groups: the threshold case and the pinch case. It was found that the pinch case which TSOFC = 1173 K yields higher total cost index than the CondBio-CathRec at the base conditions. It was also found that the pinch case can become a threshold case by adjusting split fraction or operating at lower fuel utilization. The total cost index of the threshold cases is lower than that of the pinch case. Moreover, it was found that some conditions can give lower total cost index than that of the CondBio-CathRec at the base conditions. 相似文献
4.
Watcharapong Khaodee Nicha Tangchupong Bunjerd Jongsomjit Navadol Laosiripojana Piyasan Praserthdam Suttichai Assabumrungrat 《Journal of Industrial and Engineering Chemistry》2010,16(3):411-418
Catalytic performances of sulfated zirconia catalysts with various contents of sulfur (from 0.1 to 0.75%) on isosynthesis were studied. It was firstly found that undoped-zirconia synthesized from zirconyl nitrate provided higher activity towards isosynthesis reaction (106 μmol kg-cat?1 s?1) compared to that synthesized from zirconyl chloride (84.9 μmol kg-cat?1 s?1). Nevertheless, the selectivity of isobutene in hydrocarbons was relatively lower. It was then observed that the catalytic reactivity and selectivity significantly improved by sulfur loading. The most suitable sulfur loading content seems to be at 0.1%, which gave the highest reaction rate and selectivity of isobutene. By applying several characterization techniques, i.e. BET, XRD, NH3- and CO2-TPD and SEM, it was revealed that the high reaction rate and selectivity towards isosynthesis reaction of sulfated zirconia catalysts are related to the acid–base properties, Zr3+ quantity and phase composition. 相似文献
5.
Nano-particulate high surface area CeO2 was found to have a useful methanol decomposition activity producing H2, CO, CO2, and a small amount of CH4 without the presence of steam being required under solid oxide fuel cell temperatures, 700-1000 °C. The catalyst provides high resistance toward carbon deposition even when no steam is present in the feed. It was observed that the conversion of methanol was close to 100% at 850 °C, and no carbon deposition was detected from the temperature programmed oxidation measurement.The reactivity toward methanol decomposition for CeO2 is due to the redox property of this material. During the decomposition process, the gas-solid reactions between the gaseous components, which are homogeneously generated from the methanol decomposition (i.e., CH4, CO2, CO, H2O, and H2), and the lattice oxygen on ceria surface take place. The reactions of adsorbed surface hydrocarbons with the lattice oxygen ( can produce synthesis gas (CO and H2) and also prevent the formation of carbon species from hydrocarbons decomposition reaction (CnHm⇔nC+m/2H2). VO·· denotes an oxygen vacancy with an effective charge 2+. Moreover, the formation of carbon via Boudouard reaction (2CO⇔CO2+C) is also reduced by the gas-solid reaction of carbon monoxide with the lattice oxygen .At steady state, the rate of methanol decomposition over high surface area CeO2 was considerably higher than that over low surface area CeO2 due to the significantly higher oxygen storage capacity of high surface area CeO2, which also results in the high resistance toward carbon deposition for this material. In particular, it was observed that the methanol decomposition rate is proportional to the methanol partial pressure but independent of the steam partial pressure at 700-800 °C. The addition of hydrogen to the inlet stream was found to have a significant inhibitory effect on the rate of methanol decomposition. 相似文献
6.
Nonchanok Ngoenthong Vut Tongnan Thana Sornchamni Nuchanart Siri-nguan N. Laosiripojana Unalome Wetwatana Hartley 《International Journal of Hydrogen Energy》2021,46(48):24581-24590
A stainless steel micro-channel reactor was tailor-made to an in house-design for process intensification propose. The reactor was used for a two-step thermochemical cycles of H2O and CO2 co-splitting reaction, in the presence of La0.3Sr0.7Co0.7Fe0.3O3 (LSCF). LSCF was coated inside the reactor using wash-coat technique. Oxygen storage capacity of LSCF was determined at 4465 μmol/g, using H2-TPR technique. H2O-TPSR and CO2-TPSR results suggested that a formation of surface hydroxyl group was the cause of H2O splitting favorable behavior of LSCF. Optimal operating reduction/oxidation temperature was found at 700 °C, giving 2266 μmol/g of H2, 705 μmol/g of CO, and 67% of solid conversion, when the H2O and CO2 ratio was 1 to 1, and WSHV was 186,000 mL/g.h. Activation energy of H2O spitting and CO2 splitting was estimated at 87.33 kJ/mol, and 102.85 kJ/mol The pre-exponential factor of H2O splitting and CO2 splitting was 595.24 s?1 and 698.79 s?1, respectively. 相似文献
7.
通过分析物业管理行业人才的需求现状,针对当前物业管理企业中的人力资源管理存在的问题及原因,提出实施人力资源发展战略的必要性,并对实施物业企业人力资源发展战略的四方面途径做了论述。 相似文献
8.
Yoo Byoung-Wook Kim Bom Joshi Pankaj Kwon Sung-Ok Kim YeonJin Oh Jung-Sook Kim Jeongseon Oh Se-Young Lim Ji-Ae Choi Byung-Sun Kim Yu-Mi Eom Sang-Yong Hong Young-Seob Sohn Seok-Joon Park Kyung-Su Pyo Heesoo Kim Ho Ha Mina Park Jung-Duck Kwon Ho-Jang Lee Sang-Ah 《Food science and biotechnology》2018,27(4):1227-1237
Food Science and Biotechnology - This study was aimed to examine the association the blood/urinary concentration of toxic metal (Hg, Pb, and Cd) with children’s dietary patterns. This... 相似文献
9.
P. Dokmaingam J.T.S. Irvine S. Assabumrungrat S. Charojrochkul N. Laosiripojana 《International Journal of Hydrogen Energy》2010,35(24):13271-13279
Mathematical models of an Intermediate Temperature Solid Oxide Fuel Cell (IT-SOFC) with indirect internal reforming operation (IIR-SOFC) fueled by methane were developed. The models were based on a steady-state heterogeneous two-dimensional tubular-design SOFC. The benefit in adding oxygen to methane and steam as the feed for autothermal reforming reaction on the thermal behavior and SOFC performance was simulated. The results indicated that smoother temperature gradient with lower local cooling at the entrance of the reformer channel can be achieved by adding a small amount of oxygen. However, the electrical efficiency noticeably decreased when too high oxygen content was added due to the loss of hydrogen generation from the oxidation reaction; hence, the inlet oxygen to carbon (O/C) molar ratio must be carefully controlled. Another benefit of adding oxygen is the reduction of excess steam requirement, which could reduce the quantity of heat required to generate the steam and eventually increases the overall system performance. It was also found that the operating temperature strongly affects the electrical efficiency achievement and temperature distribution along the SOFC system. By increasing the operating temperature, the system efficiency increases but a significant temperature gradient is also detected. The system with a counter-flow pattern was compared to that with a co-flow pattern. The co-flow pattern provided smoother temperature gradient along the system due to better matching between the heat supplied from the electrochemical reaction and the heat required for the steam reforming reaction. However, the electrical efficiency of the co-flow pattern is lower due to the higher cell polarization at a lower system temperature. 相似文献
10.
Anusorn Boonpoke Siriluk Chiarakorn Navadol Laosiripojana Sirintornthep Towprayoon Amnat Chidthaisong 《Korean Journal of Chemical Engineering》2012,29(1):89-94
Bagasse-based activated carbon (BAC) and amine-modified BAC were prepared and investigated for CO2 adsorption capacity. Modifying BAC with amines resulted in a decrease of surface area, but the decreasing magnitude varied
depending on type and loading rate of amines. At room temperature, the unmodified BAC was able to adsorb more CO2 than the amine-modified BAC. This ability was related to the higher surface area of unmodified than that of the modified
BAC. When temperature increased, CO2 adsorption capacity of all absorbents was decreased. However, above 323 K and a concentration of CO2 lower than 30% v/v, the BAC modified with PEI at 5 and 25 wt% showed higher adsorption capacity. Among all adsorbents under
15% CO2 and 348 K, BAC-PEI25 showed the highest adsorption capacity (0.20 mmol/g). 相似文献