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Efficacy of fexuprazan compared with rebamipide in Korean patients with gastritis:A matching-adjusted indirect comparison
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作者 Gwang Ha Kim Hang Lak Lee 《World Journal of Clinical Cases》 SCIE 2024年第19期3890-3897,共8页
BACKGROUND Gastritis is one of the most frequently diagnosed diseases requiring medical treatment in South Korea.Fexuprazan,a novel potassium-competitive acid blocker,has been approved for treating gastritis and erosi... BACKGROUND Gastritis is one of the most frequently diagnosed diseases requiring medical treatment in South Korea.Fexuprazan,a novel potassium-competitive acid blocker,has been approved for treating gastritis and erosive esophagitis.Meanwhile,rebamipide is the most commonly used mucoprotective agent for acute and chronic gastritis in real-world settings in South Korea.However,there have been no studies comparing the efficacy of these two drugs yet.AIM To compare the efficacy of fexuprazan with that of rebamipide for acute and chronic gastritis.METHODS This was a matching-adjusted indirect comparison.Individual patient data from a phase III study of fexuprazan(10 mg BID)were compared with cumulative data from two matching studies of rebamipide(100 mg TID).Erosion improvement and healing rates were compared between two weeks of fexurapan,two weeks of rebamipide,and four weeks of rebamipide.The two main outcome variables were presented as percentages,and the risk differences(RD)and 95%confidence intervals(CI)were calculated for the relative treatment effects.RESULTS In the primary analysis,the erosion improvement and healing rates after a twoweek treatment with fexuprazan were 64.5%and 53.2%,respectively,while a twoweek treatment with rebamipide resulted in erosion improvement and healing rates of 43.6%(RD:21.0%;95%CI:9.6-32.3;P<0.01)and 35.6%(RD:17.6%;95%CI:6.1-29.2;P=0.003),respectively.In the additional analysis,the erosion improvement and healing rates for the two-week fexuprazan treatment(64.2%and 51.2%,respectively)were similar to those obtained during a four-week treatment with rebamipide(60.6%;RD:3.6%;95%CI:-9.8,17.0;P=0.600 and 53.5%;RD:-2.3%;95%CI:-16.1,11.5;P=0.744,respectively).CONCLUSION The two-week fexuprazan treatment was superior to the two-week rebamipide treatment and similar to the fourweek rebamipide treatment for patients with gastritis. 展开更多
关键词 GASTRITIS Erosive gastritis Fexuprazan REBAMIPIDE Matching-adjusted indirect comparison indirect treatment comparison
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Indirect neutron radiography experiment on dummy nuclear fuel rods for pressurized water reactors at CMRR
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作者 Yong Sun Qi-Biao Wang +11 位作者 Peng-Cheng Li Ming Xia Bin Liu He-Yong Huo Wei Yin Yang Wu Sheng Wang Chao Cao Xin Yang Run-Dong Li Hang Li Bin Tang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第11期13-27,共15页
Nuclear energy is a vital source of clean energy that will continue to play an essential role in global energy production for future generations.Nuclear fuel rods are core components of nuclear power plants,and their ... Nuclear energy is a vital source of clean energy that will continue to play an essential role in global energy production for future generations.Nuclear fuel rods are core components of nuclear power plants,and their safe utilization is paramount.Due to its inherent high radioactivity,indirect neutron radiography(INR)is currently the only viable technology for irradiated nuclear fuel rods in the field of energy production.This study explores the experimental technique of indirect neutron computed tomography(INCT)for radioactive samples.This project includes the development of indium and dysprosium conversion screens of different thicknesses and conducts resolution tests to assess their performance.Moreover,pressurized water reactor(PWR)dummy nuclear fuel rods have been fabricated by self-developing substitute materials for cores and outsourcing of mechanical processing.Experimental research on the INR is performed using the developed dummy nuclear fuel rods.The sparse reconstruction technique is used to reconstruct the INR results of 120 pairs of dummy nuclear fuel rods at different angles,achieving a resolution of 0.8 mm for defect detection using INCT. 展开更多
关键词 Conversion screen DYSPROSIUM indirect neutron computed tomography Dummy nuclear fuel rods
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Behavior of exciton in direct−indirect band gap Al_(x)Ga_(1−x)As crystal lattice quantum wells
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作者 Yong Sun Wei Zhang +10 位作者 Shuang Han Ran An Xin-Sheng Tang Xin-Lei Yu Xiu-Juan Miao Xin-Jun Ma Xianglian Pei-Fang Li Cui-Lan Zhao Zhao-Hua Ding Jing-Lin Xiao 《Journal of Semiconductors》 EI CAS CSCD 2024年第3期64-70,共7页
Excitons have significant impacts on the properties of semiconductors.They exhibit significantly different properties when a direct semiconductor turns in to an indirect one by doping.Huybrecht variational method is a... Excitons have significant impacts on the properties of semiconductors.They exhibit significantly different properties when a direct semiconductor turns in to an indirect one by doping.Huybrecht variational method is also found to influence the study of exciton ground state energy and ground state binding energy in Al_(x)Ga_(1−x)As semiconductor spherical quantum dots.The Al_(x)Ga_(1−x)As is considered to be a direct semiconductor at AI concentration below 0.45,and an indirect one at the concentration above 0.45.With regards to the former,the ground state binding energy increases and decreases with AI concentration and eigenfrequency,respectively;however,while the ground state energy increases with AI concentration,it is marginally influenced by eigenfrequency.On the other hand,considering the latter,while the ground state binding energy increases with AI concentration,it decreases with eigenfrequency;nevertheless,the ground state energy increases both with AI concentration and eigenfrequency.Hence,for the better practical performance of the semiconductors,the properties of the excitons are suggested to vary by adjusting AI concentration and eigenfrequency. 展开更多
关键词 exciton effects aluminum gallium arsenide crystal direct band gap semiconductor indirect band gap semiconductor
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Omental fibroma combined with right indirect inguinal hernia masquerades as a scrotal tumor: A case report
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作者 Ping Zhou Chan-Hui Jin +6 位作者 Ying Shi Guo-Qing Ma Wen-Hao Wu Yu Wang Kun Cai Wu-Feng Fan Tian-Bao Wang 《World Journal of Clinical Cases》 SCIE 2024年第5期988-994,共7页
BACKGROUND The most common causes of scrotal enlargement in patients include primary tumor of the scrotum,inflammation,hydrocele of the tunica vaginalis,and indirect inguinal hernia;scrotal enlargement caused by exter... BACKGROUND The most common causes of scrotal enlargement in patients include primary tumor of the scrotum,inflammation,hydrocele of the tunica vaginalis,and indirect inguinal hernia;scrotal enlargement caused by external tumors of the scrotum is rare.The patient had both a greater omentum tumor and an inguinal hernia,and the tumor protruded into the scrotum through the hernia sac,which is even rarer.Moreover,omental tumors are mostly metastatic,and primary omental fibroma is rare.CASE SUMMARY Here,we report a rare case of a 25-year-old young man with scrotal enlargement and pain for 3 months.Preoperative examination and multidisciplinary discu-ssions considered intra-abdominal tumor displacement and inguinal hernia,and intraoperative exploration confirmed that the greater omentum tumor protruded into the scrotum.Therefore,tumor resection and tension-free inguinal hernia repair were performed.The final diagnosis was benign fibroma of the greater omentum accompanied by an indirect inguinal hernia.CONCLUSION This unusual presentation of a common inguinal hernia disease illustrates the necessity of performing detailed history taking,physical examination,and imaging before surgery. 展开更多
关键词 HERNIA indirect inguinal hernia FIBROMA Omental tumor Scrotal tumor Greater omentum Case report
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Fracture propagation and evolution law of indirect fracturing in the roof of broken soft coal seams
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作者 Haifeng Zhao Pengyue Li +1 位作者 Xuejiao Li Wenjie Yao 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第1期78-102,共25页
Indirect fracturing in the roof of broken soft coal seams has been demonstrated to be a feasible technology.In this work,the No.5 coal seam in the Hancheng block was taken as the research object.Based on the findings ... Indirect fracturing in the roof of broken soft coal seams has been demonstrated to be a feasible technology.In this work,the No.5 coal seam in the Hancheng block was taken as the research object.Based on the findings of true triaxial hydraulic fracturing experiments and field pilot under this technology and the cohesive element method,a 3D numerical model of indirect fracturing in the roof of broken soft coal seams was established,the fracture morphology propagation and evolution law under different conditions was investigated,and analysis of main controlling factors of fracture parameters was conducted with the combination weight method,which was based on grey incidence,analytic hierarchy process and entropy weight method.The results show that“士”-shaped fractures,T-shaped fractures,cross fractures,H-shaped fractures,and“干”-shaped fractures dominated by horizontal fractures were formed.Different parameter combinations can form different fracture morphologies.When the coal seam permeability is lower and the minimum horizontal principal stress difference between layers and fracturing fluid injection rate are both larger,it tends to form“士”-shaped fractures.When the coal seam permeability and minimum horizontal principal stress between layers and perforation position are moderate,cross fractures are easily generated.Different fracture parameters have different main controlling factors.Engineering factors of perforation location,fracturing fluid injection rate and viscosity are the dominant factors of hydraulic fracture shape parameters.This study can provide a reference for the design of indirect fracturing in the roof of broken soft coal seams. 展开更多
关键词 indirect fracturing Roof of coal seam Fracture propagation and evolution Coalbed methane Cohesive element method Combination weight method
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Experimental Study and Thermal Modelling of Cocoa Shell Convective Drying in an Indirect Solar Dryer
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作者 Siaka Touré Adjo Christelle Ogo Modibo Sidibé 《Modeling and Numerical Simulation of Material Science》 2024年第2期69-78,共10页
The concern of the present work is the convective drying of empty cocoa shells in an indirect solar dryer. Some drying experiments, using one sample, were carried out. During the experiments, the sample is introduced ... The concern of the present work is the convective drying of empty cocoa shells in an indirect solar dryer. Some drying experiments, using one sample, were carried out. During the experiments, the sample is introduced in the drying chamber. Then at steady time intervals, the sample is withdrawn from the drying chamber, for a rapid weighing. After each weighing, the sample is reintroduced in the dryer. At each time interval, the ambient temperature of the drying chamber and its relative humidity γ are measured by a thermo-hygrometer. From the experimental data, a theoretical determination of the moisture evaporated from the product was performed and a good agreement was found between the theoretical and experimental values, confirmed by the value of the RMSE. Those calculations used the constants in the Nusselt number found in literature. Then those constants were evaluated again, to get new values more suitable with the experimental data. The dimensionless numbers of Nusselt, Grashof and Prandtl were calculated. That allowed the calculation of the average value of the Nusselt number. The average convective heat transfer coefficient was determined. 展开更多
关键词 Shells of Cocoa Pods indirect Solar Dryer Moisture Evaporated Constants of the Nusselt Number Convective Heat Transfer Coefficient
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Factors that influence the results of indirect decompression employing oblique lumbar interbody fusion
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作者 Andrey E Bokov Svetlana Y Kalinina +2 位作者 Mingiyan I Khaltyrov Alexandr P Saifullin Anatoliy A Bulkin 《World Journal of Orthopedics》 2024年第8期734-743,共10页
BACKGROUND Indirect decompression is one of the potential benefits of anterior reconstruction in patients with spinal stenosis.On the other hand,the reported rate of revision surgery after indirect decompression highl... BACKGROUND Indirect decompression is one of the potential benefits of anterior reconstruction in patients with spinal stenosis.On the other hand,the reported rate of revision surgery after indirect decompression highlights the necessity of working out prediction models for the radiographic results of indirect decompression with assessing their clinical relevance.AIM To assess factors that influence radiographic and clinical results of the indirect decompression in patients with stenosis of the lumbar spine.METHODS This study is a single-center cross-sectional evaluation of 80 consecutive patients(17 males and 63 females)with lumbar spinal stenosis combined with the instability of the lumbar spinal segment.Patients underwent single level or bisegmental spinal instrumentation employing oblique lumbar interbody fusion(OLIF)with percutaneous pedicle screw fixation.Radiographic results of the indirect decompression were assessed using computerized tomography,while MacNab scale was used to assess clinical results.RESULTS After indirect decompression employing anterior reconstruction using OLIF,the statistically significant increase in the disc space height,vertebral canal square,right and left lateral canal depth were detected(Р<0.0001).The median(M)relative vertebral canal square increase came toМ=24.5%with 25%-75%quartile border(16.3%;33.3%)if indirect decompression was achieved by restoration of the segment height.In patients with the reduction of the upper vertebrae slip,the median of the relative increase in vertebral canal square accounted for 49.5%with 25%-75%quartile border(2.35;99.75).Six out of 80 patients(7.5%)presented with unsatisfactory results because of residual nerve root compression.The critical values for lateral recess depth and vertebral canal square that were associated with indirect decompression failure were 3 mm and 80 mm2 respectively.CONCLUSION Indirect decompression employing anterior reconstruction is achieved by the increase in disc height along the posterior boarder and reduction of the slipped vertebrae in patients with degenerative spondylolisthesis.Vertebral canal square below 80 mm2 and lateral recess depth less than 3 mm are associated with indirect decompression failures that require direct microsurgical decompression. 展开更多
关键词 indirect decompression Anterior reconstruction Central lumbar spinal stenosis Degenerative spondylolisthesis Lateral recess stenosis Spinal instability Oblique lateral interbody fusion
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Analysis of Standards and Effects of Police Indirect Court of Human Rights——Taking“Akbay and Others v.Germany”as an Example
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作者 刘梅湘 侯慧茹 CHEN Feng 《The Journal of Human Rights》 2024年第1期202-230,共29页
The European Court of Human Rights(ECtHR)has ruled that illegal indirect entrapment must meet three criteria simultaneously.This mixed standard requires that the previous direct entrapment violates the“essentially pa... The European Court of Human Rights(ECtHR)has ruled that illegal indirect entrapment must meet three criteria simultaneously.This mixed standard requires that the previous direct entrapment violates the“essentially passive,”subsequent indirect entrapment satisfies the“reasonable foreseeability,”and police entrapment of secondary defendants to commit crimes is considered“decisive.”The legal consequences of indirect entrapment are distinguished between general indirect entrapment and illegal indirect entrapment.The basic position of the ECtHR on the consequences of illegal indirect entrapment has shifted from supporting mitigating penalties to recognizing procedural dismissal,and general indirect entrapment is considered a mitigating factor in sentencing.Against the backdrop of increasing internationalization of criminal justice standards,the above criteria and positions have strong implications for the improvement of relevant rules in China. 展开更多
关键词 indirect entrapment direct entrapment standard of legitimacy legal consequence
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Indirect Electroanalysis of 3-Methyl-4-Nitrophenol in Water Using Carbon Fiber Microelectrode Modified with Nickel Tetrasulfonated Phthalocyanine Complex
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作者 Yibor Fabrice Roland Bako Serge Foukmeniok Mbokou +2 位作者 Boukaré Kaboré Issa Tapsoba Maxime Pontié 《Materials Sciences and Applications》 2024年第2期25-35,共11页
Electrochemical detection of 3-methyl-4-nitrophenol (MNP) in direct phenol oxidation occurs at high potentials and generally leads to progressive passivation of the electrochemical sensor. This study describes the use... Electrochemical detection of 3-methyl-4-nitrophenol (MNP) in direct phenol oxidation occurs at high potentials and generally leads to progressive passivation of the electrochemical sensor. This study describes the use of a carbon fiber microelectrode modified with a tetrasulfonated nickel phthalocyanine complex for the detection of MNP at a lower potential than that of direct phenol oxidation. The MNP voltammogram showed the presence of an anodic peak at -0.11 V vs SCE, corresponding to the oxidation of the hydroxylamine group generated after the reduction of the nitro group. The effect of buffer pH on the peak current and SWV parameters such as frequency, scan increment, and pulse amplitude were studied and optimized to have better electrochemical response of the proposed sensor. With these optimal parameters, the calibration curve shows that the peak current varied linearly as a function of MNP concentration, leading to a limit of detection (LoD) of 1.1 μg/L. These results show an appreciable sensitivity of the sensor for detecting the MNP at relatively low potentials, making it possible to avoid passivation phenomena. 展开更多
关键词 3-Methyl-4-Nitrophenol Carbon Fiber Microelectrode Nickel Tetrasulfonated Phthalocyanine indirect Electroanalysis Square Wave Voltammetry
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SO_2 emission characteristics from co-firing of petroleum coke and coal in circulating fluidized bed 被引量:2
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作者 赵长遂 王文选 +2 位作者 王凤君 陈传敏 韩松 《Journal of Southeast University(English Edition)》 EI CAS 2005年第1期48-52,共5页
Combustion and sulfur retention experiments of mixed fuel of petroleum cokeand coal were conducted on a pilot-scale circulating fluidized bed (CFB) combustor with the thermalinput of 0. 6 MW. The effects of several pa... Combustion and sulfur retention experiments of mixed fuel of petroleum cokeand coal were conducted on a pilot-scale circulating fluidized bed (CFB) combustor with the thermalinput of 0. 6 MW. The effects of several parameters, such as the primary air percentage, excess aircoefficient, bed temperature, Ca/S molar ratio and mass ratio of petroleum coke to coal on SO_2emission were verified. Experimental results show that when the ratio of petroleum coke to coal inthe mixed fuel increases, the SO_2emission increases. The maximum SO_2 emission appears when purecoke burns. The SO_2 concentration in flue gas reduces with the increase in the primary airpercentage, excess air coefficient and Ca/S molar ratio for all kinds of fuel mixtures. Therangebetween 830 t and 850 t is the optimal temperature for sulfur retention during co-firing ofpetroleum coke and coal with the mass ratio R of 1 and 3 in CFB. 展开更多
关键词 circulating fluidized bed petroleum coke COAL co-firing DESULFURIZATION
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Emissions of SO_2, NO and N_2O in a circulating fluidized bed combustor during co-firing coal and biomass 被引量:27
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作者 XIE Jian-jun YANG Xue-min +3 位作者 ZHANG Lei DING Tong-li SONG Wen-li LIN Wei-gang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第1期109-116,共8页
This paper presents the experimental investigations of the emissions of SO2, NO and N20 in a bench scale circulating fluidized bed combustor for coal combustion and co-firing coal and biomass. The thermal capacity of ... This paper presents the experimental investigations of the emissions of SO2, NO and N20 in a bench scale circulating fluidized bed combustor for coal combustion and co-firing coal and biomass. The thermal capacity of the combustor is 30 kW. The setup is electrically heated during startup. The infuence of the excess air, the degree of the air staging, the biomass share and the feeding position of the fuels on the emissions of SO2, NO and N2O were studied. The results showed that an increase in the biomass shares resulted in an increase of the CO concentration in the flue gas, probably due to the high volatile content of the biomass. In co-firing, the emission of SO2 increased with increasing biomass share slightly, however, non-linear increase relationship between SO2 emission and fuel sulfur content was observed. Air staging significantly decreased the NO emission without raising the SO2 level. Although the change of the fuel feeding position from riser to downer resulted in a decrease in the NO emission level, no obvious change was observed for the SO2 level. Taking the coal feeding position R as a reference, the relative NO emission could significantly decrease during co-firing coal and biomass when feeding fuel at position D and keeping the first stage stoichiometry greater than 0.95. The possible mechanisms of the sulfur and nitrogen chemistry at these conditions were discussed and the ways of simultaneous reduction of SO2, NO and N2O were proposed. 展开更多
关键词 circulating fluidized bed (CFB) combustion SO2 NO N2O co-firing BIOMASS
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Co-firing of coal and biomass in oxy-fuel fluidized bed for CO2 capture: A review of recent advances 被引量:4
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作者 Qinwen Liu Yan Shi +1 位作者 Wenqi Zhong Aibing Yu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第10期2261-2272,共12页
The co-firing of coal and biomass in oxy-fuel fluidized beds is one of the most promising technologies for capturing CO2.This technology has attracted wide attention from academia and industry in recent years as a neg... The co-firing of coal and biomass in oxy-fuel fluidized beds is one of the most promising technologies for capturing CO2.This technology has attracted wide attention from academia and industry in recent years as a negative emission method to capture CO2 produced by carbon contained in biomass.In the past decades,many studies have been carried out regarding experiments and numerical simulations under oxy-fuel combustion conditions.This paper firstly briefly discusses the techno-economic viability of the biomass and coal co-firing with oxycombustion and then presents a review of recent advancements involving experimental research and computational fluid dynamics(CFD)simulations in this field.Experimental studies on mechanism research,such as thermogravimetric analysis and tube furnace experiments,and fluidized bed experiments based on oxy-fuel fluidized beds with different sizes as well as the main findings,are summarized as a part of this review.It has been recognized that CFD is a useful approach for understanding the behaviors of the co-firing of coal and biomass in oxyfuel fluidized beds.We summarize a recent survey of published CFD research on oxy-fuel fluidized bed combustion,which categorized into Eulerian and Lagrangian methods.Finally,we discuss the challenges and interests for future research. 展开更多
关键词 OXY-FUEL combustion co-firing of COAL and BIOMASS OXY-FUEL fluidized BED CFD simulation
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Waste biomass from production process co-firing with coal in a steam boiler to reduce fossil fuel consumption:A case study 被引量:3
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作者 Hongyan Gu Kai Zhang +3 位作者 Yaodong Wang Ye Huang Neil Hewitt Anthony P Roskilly 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第3期413-419,共7页
Waste biomass is always generated during the production process in industries. The ordinary way to get rid of the waste biomass is to send them to landfill or burn it in the open field. The waste may potentially be us... Waste biomass is always generated during the production process in industries. The ordinary way to get rid of the waste biomass is to send them to landfill or burn it in the open field. The waste may potentially be used for co-firing with coal to save fossil fuel consumption and also reduce net carbon emissions. In this case study, the bio-waste from a Nicotiana Tahacum (NT) pre-treatment plant is used as the biomass to co-fire with coal. The samples of NT wastes were analysed. It was found that the wastes were of the relatively high energy content which were suitable for co-firing with coal. To investigate the potential and benefits for adding NT wastes to a Fluidised Bed Combustion (FBC) boiler in the plant, detailed modelling and simulation are carried out using the European Coal Liquefaction Process Simulation and Evaluation (ECLIPSE) process simulation package. The feedstock blending ratios of NT waste to coal studied in this work are varied from 0% to 30%. The results show that the addition of NT wastes may decrease the emissions of CO2 and SOx without reducing the boiler performance. 展开更多
关键词 COAL waste biomass co-firing nicotiana tabacum waste emissions reduction
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Low SO_2 emission from CFB co-firing MSW and bituminous 被引量:1
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作者 LUQing-gang LIZhi-wei NAYong-jie BAOShao-lin SUNYun-kai HEJun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2004年第5期821-824,共4页
Influence of co-firing rate on SO 2 emission from co-firing municipal solid waste(MSW) and bituminous containing high amount of sulfur(1.79%) was studied in a 0.15 MWt circulating fluidized bed(CFB). The temperature ... Influence of co-firing rate on SO 2 emission from co-firing municipal solid waste(MSW) and bituminous containing high amount of sulfur(1.79%) was studied in a 0.15 MWt circulating fluidized bed(CFB). The temperature selected is 1123 K, typical for MSW incineration using CFB. The particle concentration in the dilution zone of the furnace, the alkali metal concentration and sulfate concentration in the recirculating ash and fly ash, and flue gas composition were determined. The results showed that the addition of MSW leads to a significant decrease in SO 2 emission. Concentration of SO 2 in flue gas decreased to 0 with the co-firing rate greater than 51%. This reduction in SO 2 emission is attributed both to the high particle concentration in the dilution zone of the furnace, the high content of alkali metals in the bed material, and to the comparatively high concentration of HCl in flue gas during co-firing of MSW and bituminous. 展开更多
关键词 co-firing municipal solid waste bituminous CFB SO 2
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Effects of Flue Gas Internal Recirculation on NOx and SOx Emissions in a Co-Firing Boiler 被引量:2
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作者 Jun Li Xiaolei Zhang +1 位作者 Weihong Yang Wlodzimierz Blasiak 《International Journal of Clean Coal and Energy》 2013年第2期13-21,共9页
Volumetric combustion has been developed to realize a high substitution ratio of biomass in co-firing boilers, which features an intensive flue gas internal recirculation inside furnace. However, the characteristics o... Volumetric combustion has been developed to realize a high substitution ratio of biomass in co-firing boilers, which features an intensive flue gas internal recirculation inside furnace. However, the characteristics of NOx and SOx emissions in large-scale boilers with volumetric combustion were not fully clear. In this paper, an Aspen Plus model of volumetric combustion system was built up based on a co-firing boiler. In order to characterize the reductions of NOx and SOx, three biomass substitution ratios were involved, namely, 100% biomass, 45% biomass with 55% coal, and 100% coal. The effects of flue gas recirculation ratio, air preheating temperature, oxygen concentration, and fuel types on pollutants emission in the volumetric combustion system were investigated. According to the results, it was concluded the higher substitution ratio of biomass in a co-firing boiler, the lower emissions of NOx and SOx. Moreover, flue gas internal recirculation is an effective pathway for NOx reduction and an increased recirculation ratio resulted in a significant decreasing of NOx emission;however, the SOx increased slightly. The influences of air preheating temperature and O2 concentration on NOx emission were getting weak with increasing of recirculation ratio. When 10% or even higher of flue gas was recycled, it was observed that almost no NOx formed thermodynamically under all studied conditions. Finally, to reach a low emission level of NOx, less energy would be consumed during biomass combustion than coal combustion process for internal recirculation of flue gas. 展开更多
关键词 FLUE Gas INTERNAL Recirculation co-firing NOx SOX
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Air Quality Impact of Biomass Co-Firing with Coal at a Power Plant in the Greater Houston Area 被引量:1
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作者 Iqbal Hossan Venkata Sai Vamsi Botlaguduru +2 位作者 Hongbo Du Raghava Rao Kommalapati Ziaul Huque 《Open Journal of Air Pollution》 2018年第3期263-285,共23页
The Houston-Galveston-Brazoria (HGB) area of Texas is a moderate nonattainment region for ozone, and has a history of severe summer ozone episodes. W. A. Parish power plant (WAP) located in the greater Houston area is... The Houston-Galveston-Brazoria (HGB) area of Texas is a moderate nonattainment region for ozone, and has a history of severe summer ozone episodes. W. A. Parish power plant (WAP) located in the greater Houston area is the largest coal and natural gas based electricity generating unit (EGU) in Texas. Forest residue is an abundant renewable resource, and can be used to offset coal usage at EGUs. This study evaluates the impact of co-firing 5%, 10%, and 15% (energy-basis) of forest residue at WAP on the air quality of the HGB area. Photochemical modeling with Comprehensive Air Quality Model with Extensions (CAMx) was conducted to investigate the air quality at three air quality monitoring sites (C696, C53, C556) in the HGB area, under two source scenarios (all-sources, point + biogenic sources). Significant reduction of SO2 and O3 was observed for 10% and 15% co-firing ratios at monitoring station (C696) close to WAP. The maximum reduction of ozone observed for 15% co-firing is 4.7% and 6.3% for all-sources and point + biogenic sources scenarios respectively. The reduction in other criteria air pollutants is not significant at all locations. The overall results from this study indicate that biomass co-firing at WAP would not lead to a significant reduction in ozone concentrations in the region during periods of peak ozone. 展开更多
关键词 Ozone HOUSTON PHOTOCHEMICAL Modeling BIOMASS co-firing
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Compression behavior of 316L lattice structures produced by indirect additive manufacturing 被引量:1
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作者 Yan-peng Wei Hao Yang +4 位作者 Jing-chang Cheng Peng Gao Jian Shi Feng Lin Bo Yu 《China Foundry》 SCIE CAS CSCD 2023年第2期83-88,共6页
As a new type of lightweight structure,metallic lattice structure has higher stiffness and strength to weight ratio.To freely obtain 316L lattice structures with designed cell structure and adjustable porosity,additiv... As a new type of lightweight structure,metallic lattice structure has higher stiffness and strength to weight ratio.To freely obtain 316L lattice structures with designed cell structure and adjustable porosity,additive manufacturing combined with investment casting was conducted to fabricate the 316L lattice structures with Kelvin cell.The compression simulation of 316L lattice structures with different porosities was carried out by using the finite element method.The numerical simulation results were verified by compression experiment,and the simulated results were consistent with the compression tests.The compressive mechanical properties of 316L lattice structures are directly related to porosity and independent of strut diameters.The 316L lattice structures with Kelvin cell have a smooth stress-strain curve and obvious plastic platform,and the hump stress-strain curves are avoided. 展开更多
关键词 316L lattice structures indirect additive manufacturing compression behavior investment casting finite element simulation
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Indirect Vector Control of Linear Induction Motors Using Space Vector Pulse Width Modulation 被引量:1
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作者 Arjmand Khaliq Syed Abdul Rahman Kashif +5 位作者 Fahad Ahmad Muhammad Anwar Qaisar Shaheen Rizwan Akhtar Muhammad Arif Shah Abdelzahir Abdelmaboud 《Computers, Materials & Continua》 SCIE EI 2023年第3期6263-6287,共25页
Vector control schemes have recently been used to drive linear induction motors(LIM)in high-performance applications.This trend promotes the development of precise and efficient control schemes for individual motors.T... Vector control schemes have recently been used to drive linear induction motors(LIM)in high-performance applications.This trend promotes the development of precise and efficient control schemes for individual motors.This research aims to present a novel framework for speed and thrust force control of LIM using space vector pulse width modulation(SVPWM)inverters.The framework under consideration is developed in four stages.To begin,MATLAB Simulink was used to develop a detailed mathematical and electromechanical dynamicmodel.The research presents a modified SVPWM inverter control scheme.By tuning the proportional-integral(PI)controller with a transfer function,optimized values for the PI controller are derived.All the subsystems mentioned above are integrated to create a robust simulation of the LIM’s precise speed and thrust force control scheme.The reference speed values were chosen to evaluate the performance of the respective system,and the developed system’s response was verified using various data sets.For the low-speed range,a reference value of 10m/s is used,while a reference value of 100 m/s is used for the high-speed range.The speed output response indicates that themotor reached reference speed in amatter of seconds,as the delay time is between 8 and 10 s.The maximum amplitude of thrust achieved is less than 400N,demonstrating the controller’s capability to control a high-speed LIM with minimal thrust ripple.Due to the controlled speed range,the developed system is highly recommended for low-speed and high-speed and heavy-duty traction applications. 展开更多
关键词 Space vector pulse width modulation linear induction motor proportional-integral controller indirect vector control electromechanical dynamic modeling
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Emission Factors of Particulate Matter Emitted from Co-Firing of Thai Lignite and Agricultural Residues in Fixed Bed Combustor
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作者 N. Mantananont S. Garivait S. Patumsawad 《Journal of Environmental Science and Engineering》 2011年第7期890-899,共10页
Emission factors (EFs) of particulate matter (PM) derived from mono and co-firing of Thai lignite and agricultural residues have been investigated. Two sampling methods for PM, total filtration (TF) and electric... Emission factors (EFs) of particulate matter (PM) derived from mono and co-firing of Thai lignite and agricultural residues have been investigated. Two sampling methods for PM, total filtration (TF) and electrical low-pressure impactor (ELPI), were used together. The study is focused on the influence of fuel mass fraction, and of secondary air to total air; SA:TA on EFs of PM. The results have shown that EFs of PM in mass-basis given by TF method are 8.9, 5.3 and 8.1 mg/kgfuel, while 3.3, 2.7 and 3.3 mg/kgfuel when using ELPI, for firing at constant SA:TA (30%) of lignite, rice husk and bagasse, respectively. For co-firing with 30%SA of coal/rice husk, higher EFs of PM is observed. They are 7.17 and 10.9 mg/kgfuel (TF) for 40 and 70% rice husk share, respectively, or 4.18 and 5.19 mg/kgfuel (ELPI). However, lower PM emission; 1-3.3 mg/kgruel (TF) or 0.72-2.83 mg/kgfuel (ELPI) are obtained during co-firing of coal/rice husk with lower degree of air staging (i.e. 0-10% SA:TA). For the influence of oxygenation state, increasing of SA: TA leads to a low formation of ultrafine particles (Dp 〈 0.1 μm). Apart from PM, major gases (CO, NO, SO2) will be documented in this paper. 展开更多
关键词 Emission factors particulate matter co-firing Thai lignite agricultural residues fixed bed.
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Wood Pellet Co-Firing for Electric Generation Source of Income for Forest Based Low Income Communities in Alabama
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作者 Ellene Kebede Gbenga Ojumu Edinam Adozsii 《Open Journal of Energy Efficiency》 2013年第3期125-132,共8页
Alabama imports coal from other states to generate electricity. This paper assessed the direct and indirect economic impacts of wood pellet production to be co-fired with coal for power generation in Alabama. Four siz... Alabama imports coal from other states to generate electricity. This paper assessed the direct and indirect economic impacts of wood pellet production to be co-fired with coal for power generation in Alabama. Four sizes of wood pellet plants and regional input-output models were used for the analysis. The results showed that the economic impact increases with the size of the plant. Wood pellet production will have a multiplier effect on the economy especially, forest-related services, retail stores, the health service industry, and tax revenue for the government. Domestic wood pellet production can reduce the use of imported coal, allow the use of local woody biomass, and create economic activities in Alabama’s rural communities. Policies that support the production of wood pellet will serve to encourage the use of wood for power generation and support the rural economies. 展开更多
关键词 Wood PELLET Electricity co-firing Coal INPUT-OUTPUT FOREST Industry
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