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Study on SCR De NO_x mechanism through in situ electrical conductivity measurements on V_2O_5-WO_3/TiO_2 catalysts

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Rare Metals 2006年第Z2期25卷 77-83页

作者： HA Heon Phil JUNG soon Hyo LEE Jun Yub HONG Sung Ho Metal Processing Research Center Korea Institute of Science and Technology Cheongryang Seoul 130-650 Republic of Korea Power Engineering Research Institute Korea Power Engineering Company Inc. 360-9 Mabuk-ri Guseong-eup Yongin-si Gyeonggi-do 449-713 Republic of Korea

V2O5-WO3/TiO2 catalysts were prepared by impregnation method and in situ electrical conductivity measurements were carried out to investigate the reaction mechanism for ammonia SCR (selective catalytic reduction) of NOx. The electrical conductivity change with ammonia supply and the increase of electrical conductivity were mainly caused by reduction of the labile surface oxygen. The electrical conductivity change of catalysts shows close relationship with the conversion rate of NOx. Variation of conversion rate in atmosphere without gaseous oxygen also supports that the labile lattice oxygen is indispensable in the initial stage of the de NOx reaction. These results suggest that the liable lattice oxygen acts decisive role in the de NOx mechanism. They also support that De NOx reaction occurs through the Eley-Rideal type mechanism. The amount of labile oxygen can be estimated from the measurement of electrical conductivity change for catalysts with ammonia supply.

关键词： De NOx selective catalytic reduction electrical conductivity lattice oxygen

Mg-based bulk metallic glasses:A review of recent developments

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Journal of Magnesium and Alloys 2022年第4期10卷 899-914页

作者： Shi Jie Bryan Bin Kai soon Fong Beng Wah Chua Manoj Gupta Department of Mechanical Engineering National University of SingaporeSingapore 117576Singapore Singapore Institute of Manufacturing Technology 73 Nanyang DriveSingapore 637662Singapore

Metallic biomaterials have been widely used in the field of medical implants for replacement purposes and/or for regeneration of *** such as stainless steel(316 L),cobalt-chromium alloys and titanium alloys(Ti-6Al-4 V)are widely used as metallic implants ***,they often exhibit unsatisfactory results such as stress shielding,the release of toxic ions and are often permanent and invasive–where a second surgery is required to remove the implant once the bone is fully *** as a biomaterial have attracted much attention recently due to its excellent biocompatibility,similar mechanical properties to bone and *** other metals and bio ceramics,the ability for magnesium alloys to undergo biodegradation eliminates the requirement for a second surgery to remove the ***,the degradation of magnesium releases Mg2+ions,which stimulates metabolism as they are a cofactor in numerous numbers of *** the advantages of magnesium alloys,the rapid degradation of magnesium proved to be challenging as the implant is unable to retain its structural integrity sufficiently enough to act as an *** improve the corrosion resistance of magnesium alloys,researchers have been working on the synthesis and characterization of Mg-based bulk metallic glasses,which can significantly improve the corrosion resistance of Mg-based *** paper is a comprehensive review that compiles,analyzes and critically discusses the recent literature on the latest understanding of the processing,mechanical and biological characteristics of Mg-based bulk metallic glasses.

关键词： Magnesium Bulk metallic glass Amorphous Biomedical applications

Energy Efficient Transmission in Underlay CR-NOMA Networks Enabled by Reinforcement Learning

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China Communications 2020年第12期17卷 66-79页

作者： Wei Liang soon Xin Ng Jia Shi Lixin Li Dawei Wang School of Information and Electronic Northwestern Polytechnical UniversityNo.127Youyixi RoadXi’an 710072China School of Electrical and Computer Science University of SouthamptonUK State Key Lab.of Integrated Services Networks Xidian UniversityNo.2Taibainan RoadXi’an 710071China

In order to improve the energy efficiency(EE)in the underlay cognitive radio(CR)networks,a power allocation strategy based on an actor-critic reinforcement learning is proposed,where a cluster of cognitive users(CUs)can simultaneously access to the same primary spectrum band under the interference constraints of the primary user(PU),by employing the non-orthogonal multiple access(NOMA)*** the proposed scheme,the optimization of the power allocation is formulated as a non-convex optimization ***,the power allocation for different CUs is based on the actor-critic reinforcement learning model,in which the weighted data rate is set as the reward function,and the generated action strategy(*** power allocation)is iteratively criticized and *** the CU’s spectral efficiency and the PU’s interference constrains are considered in the training of the actor-critic reinforcement ***,the first order Taylor approximation as well as other manipulations are adopted to solve the power allocation optimization problem for the sake of considering the conventional channel *** to the simulation results,we find that our scheme could achieve a higher spectral efficiency for the CUs compared to a benchmark scheme without learning process as well as the existing Q-learning based method,while the resultant interference affecting the PU transmission can be maintained at a given tolerated limit.

关键词： cognitive radio network non-orthogonal multiple access scheme power allocation reinforcement learning

A recovery method using recently updated record information in shared-nothing spatial database cluster

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重庆邮电学院学报（自然科学版） 2004年第5期16卷 32-35页

作者： JEONG Myeong ho JANG Yong ll PARK soon young bae Hae young Dept. of Computer Science and Engineering Inha UniversityKoreaDept. of Computer Science and Engineering Inha UniversityKoreaDept. of Computer Science and Engineering Inha UniversityKoreaDept. of Computer Science and Engineering Inha UniversityKorea

A shared nothing spatial database cluster is system that provides continuous service even if some system failure happens in any node. So, an efficient recovery of system failure is very important. Generally, the existing method recovers the failed node by using both cluster log and local log. This method, however, cause several problems that increase communication cost and size of cluster log. This paper proposes novel recovery method using recently updated record information in shared nothing spatial database cluster. The proposed technique utilizes update information of records and pointers of actual data. This makes a reduction of log size and communication cost. Consequently, this reduces recovery time of failed node due to less processing of update operations.

关键词：空间数据库日志文件记录系统串最近更新记录

Experimental Study on the Flow Around Two Tandem Cylinders with Unequal Diameters

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Journal of Ocean University of China 2014年第5期13卷 761-770页

作者： GAO Yangyang ETIENNE Stephane WANG Xikun TAN soon Keat Ocean College Zhejiang University State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography SOA Mechanical Engineering Department Ecole Polytechnique de Montreal Maritime Research Centre and School of Civil and Environmental Engineering Nanyang Technological University

In this paper, flow around two circular cylinders in tandem arrangement with unequal diameters has been investigated using the particle image velocimetry technique(PIV) in a water channel. The upstream to downstream diameter ratio was kept constant at d/D = 2/3, the centre-to-centre distance was varied from 1.2D to 5D and the Reynolds number was varied from 1200 to 4800. The flow characteristics were analyzed through ensemble-averaged patterns of velocity, vorticity, normalized Reynolds stress contours and streamlines. Based on ensemble-averaged and instantaneous flow fields, different flow patterns, including single-wakeshedding at small spacing ratio, bi-stable flow behavior(alternating behavior of reattachment and vortex shedding) at intermediate spacing ratio and co-shedding pattern at large spacing ratio were observed. The effects of Reynolds number and the centre-to-centre spacing ratio on flow patterns and turbulent characteristics were also investigated. It was found that the diameter ratio appears to have a certain effect on the flow patterns at intermediate spacing ratios, where the reattachment of shear layer depends on the lateral width of the wake flow in the lee of the upstream cylinder. Extensive discussion on the distributions of Reynolds stress and turbulent kinetic energy was presented.

关键词： tandem cylinders with unequal diameters PIV flow patterns Reynolds stress distribution

Numerical Study of an Oscillating Smaller Cylinder in the Wake of an Upstream Larger Cylinder

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Journal of Ocean University of China 2012年第2期11卷 111-117页

作者： GAO Yangyang YU Dingyong WANG Xikun TAN soon Keat Maritime Research Centre School of Civil and Environmental EngineeringNanyang Technological University639798Singapore College of Engineering Ocean University of ChinaQingdao 266100P.R.China Nanyang Environmental and Water Research Institute Nanyang Technological University639798Singapore

A numerical study of flow around two tandem cylinders with unequal diameters was carried out. The upstream larger cylinder was fixed and the downstream smaller cylinder was allowed to oscillate in the transverse direction only. Comparisons of the experimental and numerical results were made to investigate the effects of the gap ratio on the maximum vibration amplitude and vortex shedding frequency. The results showed that the vibration response of the smaller cylinder was significantly affected by the presence of the upstream larger cylinder, and resulted in greatly reduced vibration amplitudes. With an increasing gap ratio, the vibration amplitude increased. However, the magnitude was lower than that corresponding to a single cylinder (with the same diameter as that of the downstream smaller cylinder) under the same flow conditions.

关键词： tandem cylinders with unequal diameters numerical simulation gap ratio vibration amplitude

Synthesis of New Binder Polymers for Photolithographic Patterning of Black Pixel Define Layers of Organic Light Emitting Diode

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Materials Sciences and Applications 2019年第11期10卷 687-696页

作者： Genggongwo Shi Kyeongha baek Seon Hong Ahn Jun bae Jeseob Kim Lee soon Park CCTech. Co. Ltd Hwaseong Korea School of Material Science and Engineering Ulsan National Institute of Science and Technology (UNIST) Ulsan Korea Duksan Neolux Co. Ltd. Cheonan Korea

The fabrication of black pixel define layer (PDL) on the organic light emitting diode (OLED) panel has been developed actively by using negative-tone black photoresist which contain photoinitiator, photosensitizer, binder polymer, multifunctional monomer and black mill base in order to improve the outdoor visibility of OLEDs. Cardo type binder polymer containing bulky and rigid fluorene group has been widely used in the black photoresist formulation. However, the commercial cardo binder polymer has high cost and requires high UV dose for the fine patterning of PDL in the photolithographic process. In this study we designed and synthesized various non-cardo type binder polymers and evaluated the new binder polymers in comparison with the cardo binder polymer for the improved patterning of PDL on the OLED panel.

关键词： Organic Light Emitting Diode Pixel Define Layer Photolithography One-Pot Synthesis

Successful treatment of basaloid squamous cell carcinoma in the rectosigmoid colon: A case report and review of literature

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World Journal of Clinical Cases 2020年第14期8卷 3057-3063页

作者： Taek-Gu Lee soon Man Yoon Myung Jo Kim Department of Surgery Chungbuk National University HospitalChungbuk National University College of MedicineCheongju 28644South Korea Department of Internal Medicine Chungbuk National University HospitalChungbuk National University College of MedicineCheongju 28644South Korea

BACKGROUND Compared with colorectal adenocarcinoma,basaloid squamous cell carcinomas(BSCCs)arising in the colorectum are rare and have very poor *** date,only nine cases have been *** BSCCs are extensively involved in metastasis to the lymph node,liver,and lung at *** many clinicians attempting to effectively treat BSCCs,therapeutic consensus has not been established due to lack of *** SUMMARY A 58-year-old woman presented with abdominal pain,diarrhea,fever,and *** was referred from a department of gynecology and was diagnosed with a suspicious leiomyosarcoma of the rectum or a pedunculated myoma of the *** exophytic growing mass at the right lateral wall of the rectum with an internal cystic portion and hemorrhage was observed on magnetic resonance *** patient underwent low anterior resection and total hysterectomy with bilateral *** findings revealed a cellular mass with a solid growth pattern and few glandular structures,many foci of intratumoral necrosis,and a palisading *** pathologist diagnosed tumor as a BSCC,and the patient received chemotherapy with fluorouracil/leucovorin without *** patient is currently alive 8 years after the surgery with no manifestations of metastatic colon *** Our case suggest that curative resection and chemotherapy play important roles in improving survival,and radiotherapy may be an option to avoid radiationassociated enteritis.

关键词： Basaloid squamous cell carcinomas Rectosigmoid colon Colorectal cancer Adjuvant chemotherapy Curative resection Case report

Epoxy Methacrylate Resin as Binder Polymer for Black Negative-Tone Photoresists

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Materials Sciences and Applications 2020年第5期11卷 285-295页

作者： Genggongwo Shi Kyeongha baek Seon Hong Ahn Jun bae Jeseob Kim Lee soon Park CCTech. Co. Ltd. Hwaseong South Korea School of Material Science and Engineering Ulsan National Institute of Science and Technology (UNIST) Ulsan South Korea Duksan Neolux Co. Ltd. Cheonan South Korea

Epoxy acrylate (EA) resin, which originates from epoxides, has long been served as a photocurable coating and adhesive material owing to its double bonds. Specifically, alkaline-developable EA resins can be used as a binder polymer in negative-tone photoresists. In this work, we synthesized a series of acidic polyester-type epoxy methacrylate resins, characterized the intermediates and products, and tested their performance as a binder polymer for the photolithographic micro-patterning of the pixel-defining layer on organic light-emitting diodes in comparison to a widely used commercial binder polymer. Copolymer-type binder polymer BP-2-2 was produced excellent patterning with no residue due to its high compatibility with the black mill base.

关键词： Epoxy Methacrylate Resin Negative-Tone Photoresist Binder Polymer