http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Ke, Xiwei,Li, Dongfang,Zhang, Man,Jeon, Chung-hwan,Cai, Runxia,Cai, Jin,Lyu, Junfu,Yang, Hairui Elsevier Scientific Pub. Co. 2019 Fuel processing technology Vol.186 No.-
<P><B>Abstract</B></P> <P>It is difficult to maintain enough high circulating ash rate in circulating fluidized bed (CFB) boilers if they burn the Indonesian coals due to their low ash content. Hence, the ash formation data for these coals is of significance to assessing mass balance in CFB boilers. Two kinds of Indonesian coal that were burned in the 550 MW supercritical CFB boilers in Korea, Kideco and KCH, were tested with static combustion and cold sieving method to study their ash formation characteristics. Results showed that the average primary ash particle size of these two coals is quite fine overall and nearly no gangue exists. Besides, their attrition rate constant <I>K</I> <SUB>af</SUB> is much higher than that of some other bituminous or lean coals, and with the increase of particle size, the <I>K</I> <SUB>af</SUB> decays exponentially for Kideco, while it initially increases and then decreases for KCH. In addition, the physical and chemical properties of these two Indonesian coals' ash obviously change in particle size, including density, pore structure, chemical composition, etc. The larger ash particles are composed of some hard materials, such as quartz (SiO<SUB>2</SUB>) and mullite (Al<SUB>6</SUB>Si<SUB>2</SUB>O<SUB>13</SUB>). While some other materials with lower hardness value, like hematite (Fe<SUB>2</SUB>O<SUB>3</SUB>) and gehlenite (Ca<SUB>2</SUB>Al<SUB>2</SUB>SiO<SUB>7</SUB>), become major mineral components of smaller and softer ash particles. These results indicate that the difference of chemical compositions results in the discrepancy of attrition capability for different size ash particles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Two kinds of Indonesian coal were tested to obtain their ash formation data. </LI> <LI> The ash properties obviously change in particle size. </LI> <LI> The difference of chemical compositions may result in the discrepancy of attrition rate for different size ash particles. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>The ash attrition rate of low-rank coals including these two Indonesian coals is much higher than that of some other bituminous or lean coals, and larger ash particles are more difficult to be worn.</P> <P>[DISPLAY OMISSION]</P>
입자온도의 직접적인 측정법을 이용한 석탄촤 고압 CO2 가스화 반응률에 관한 연구
이동방(Dongfang Li),김량균(Ryanggyoon Kim),송주헌(Juhun Song),전충환(Chunghwan Jeon) 대한기계학회 2011 대한기계학회 춘추학술대회 Vol.2011 No.10
Gasification kinetics of coal char of coal Wira with CO2 at elevated pressure was investigated with a Pressurized Wire Heating Reactor(PWHR). An experimental method with the capacity to heat the coal char particle and measure its temperature directly (as with a thermocouple) was developed. The effects of gasification temperature(1100 ?. 1400oC), partial pressure of carbon dioxide(0.2 ?. 0.8), and total pressure(10 ?. 30atm) on gasification rate of the coal char with CO2 were determined. The modified nth-order reaction models were then employed to analyze the reaction kinetics.
Kai Zheng,Dongfang Zhou,Jianbing Li,Li Li,Yujing Zhao 전력전자학회 2016 JOURNAL OF POWER ELECTRONICS Vol.16 No.3
A digital self-sustained phase shift modulation (DSSPSM) strategy that allows for good soft switching and dynamic response performance in the presence of step variations is presented in this paper. The working principle, soft switching characteristics, and voltage gain formulae of a LLC converter with DSSPSM have been provided separately. Furthermore, the method for realizing DSSPSM is proposed. Specifically, some key components of the proposed DSSPSM are carefully investigated, including a parameter variation analysis, the start-up process, and the zero-crossing capture of the resonant current. The simulation and experiment results verify the feasibility of the proposed control method. It is observed that the zero voltage switching of the switches and the zero current switching of the rectifier diodes can be easily realized in presence of step load variations.
Dongfang Wu,Yan-Hong Zhang,Yongdan Li 한국공업화학회 2017 Journal of Industrial and Engineering Chemistry Vol.56 No.-
Alumina-washcoated FeCrAl alloy sheets are prepared to investigate the effects of metallic substratepretreatments on the mechanical stability of monolithic catalysts. It is shown that chemical and thermalpretreatments produce different effects on the metallic surface morphology and phase, and differentmechanisms are involved in their ways of improving the washcoat adhesion. Combination of chemicaland thermal pretreatments leads to the formation of a-alumina whiskers on corroded and rough metallicsurface, thus giving the most satisfactory washcoat adhesion. It is also pointed out that not onlymechanical shock resistance but also thermal shock resistance is crucial to metallic monolithic catalysts.
Li, Zhenyu,Jiang, Qingming,Guo, Dongfang,Peng, Yangling,Zhang, Jing,Chen, Xinyu The Korean Gastric Cancer Association 2021 Journal of gastric cancer Vol.21 No.2
Plexiform fibromyxoma (PF) of the stomach is a very rare mesenchymal tumor of the gastrointestinal tract. We report the first case of PF with 2 different growth patterns pathologically confirmed after surgical resection. The tumor was characterized microscopically as infiltrative; it demonstrated diffuse growth into the smooth muscle bundles of the muscularis propria and was also multinodular and plexiform within the myxoid stroma. Immunohistochemical analysis revealed that the tumor cells were positive or weakly positive for smooth muscle actin, vimentin, and H-caldesmon and negative for desmin, CD117, CD34, CK-20, Pan-CK, Dog1, S100, ER, PR, and CD10. No mutations of C-kit and platelet-derived growth factor receptor alpha were detected. No genetic disruption of glioma-associated oncogene homolog 1 was detected by fluorescence in situ hybridization. The final diagnosis of PF was mainly based on the morphological and immunohistochemical findings.
Edible composite films: enhancing the postharvest preservation of blueberry
Shi Dongfang,Zhao Boya,Zhang Pingping,Li Ping,Wei Xinpei,Song Kai 한국원예학회 2024 Horticulture, Environment, and Biotechnology Vol.65 No.3
Blueberry is popular among consumers for their unique fl avor and rich nutritional content. However, fresh blueberry often has a short shelf life due to microbial contamination and water loss. Existing blueberry preservation methods, such as irradiation, air conditioning, and high-voltage electrostatic fi elds, have shown certain eff ectiveness. Nonetheless, their high cost and energy consumption limit their widespread use. Edible composite fi lms, created by incorporating functional substances into an edible fi lm matrix, represent an eco-friendly preservation technology. These fi lms alter the surface microenvironment of fruits by establishing a selective barrier on the fruit's surface, which signifi cantly enhances fruit storage quality. This article provides a comprehensive review of the application of edible composite fi lms in blueberry preservation. By summarizing the spoilage process of blueberry during harvesting and storage, in conjunction with fruit preservation techniques, it explores the feasibility and potential applications of edible composite fi lms. Lastly, it delves into the possibilities and challenges of integrating nanomaterials with edible composite fi lms.
Synthesis of Co-doped micro-mesoporous SAPO-11 zeolite for glycerol hydrogenolysis
Xue Li,Dongfang Wu 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.2
Co-doped micro-mesoporous SAPO-11 zeolite (Co-MSAPO-11) was synthesized and used for hydrogenolysis of glycerol. After simultaneous introduction of Co and mesopores, the pore structure and acidic properties of microporous SAPO-11 zeolite are reintegrated. The larger mesopores of Co-MSAPO-11 facilitate the diffusion of molecules and provide more space for the highly dispersed Co species. The appropriate acidity of Co-MSAPO-11 with more Lewis acid sites appears to be more helpful for the activation of reactants to intermediates, potentially increasing the probability of high selectivity to 1,2-propanediol. Therefore, Co-MSAPO-11 shows unique catalytic performance with a glycerol conversion of 94.0% and selectivity to 1,2-PDO of 90.5% under mild conditions. The possible representative model of Co-MSAPO-11 is proposed for the first time.