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Influence of dehydrating agents on the oxidative carbonylation of methanol for dimethyl carbonate synthesis over a Cu/Y-zeolite catalyst

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Chinese Journal of Chemical Engineering 2018年第5期26卷 1059-1063页

作者： Dong-ho Lee Jiin You Je-Min Woo Jung Yoon Seo Young Cheol Park jong-Seop Lee Hyunuk Kim jong-ho moon Seung Bin Park Greenhouse Gas Laboratory Korea Institute of Energy Research Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology Energy Material Laboratory Korea Institute of Energy Research

The influence of the dehydration by metal oxides on the synthesis of dimethyl carbonate （DMC） via oxidative carbonylation of methanol was studied. A Cu/Y-zeolite catalyst was prepared by the ion exchange method from CuCl2.2H2O and the commercial NH4-form of the Y type zeolite, The catalyst was characterized by X-ray fluorescence （XRF）, N2 adsorption （BET method）, X-ray diffraction （XRD）, and temperature-programmed de- sorption of ammonia （NH3-TPD） to evaluate its Cu and Cl content, surface area, structure, and acidity. Reaction tests were carried out using an autoclave （batch reactor） for 18 h at 403 K and 5.5 MPa （2CH3OH ＋ 1/2O2 ＋ CO （CH3O）2CO ＋ H2O）. The influence of various dehydrating agents （ZnO, MgO, and CaO） was examined with the aim of increasing the methanol conversion （XMeOH, MeOH conversion）. The MeOH conversion increased upon addition of metal oxides in the order CaO 〉〉 MgO 〉 ZnO, with the DMC selectivity （SDMC） following the order MgO 〉 CaO 〉 ZnO. The catalysts and dehydrating agents were characterized before and after the oxidative carbonylation of methanol by thermogravimetric and differential thermogravimetric （TG/DTG）, and XRD to con- firm that the dehydration reaction occurred via the metal oxide （MO ＋ H2O →M（OH）2）. The MeOH conversion increased from 8.7% to 14.6% and DMC selectivity increased from 39.0% to 53.1%, when using the dehydrating azent CaO.

关键词： Carbon monoxide Zeolite Catalyst Dimethyl carbonate Oxidative carbonylation Dehydrating agent

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Small sphincterotomy combined with endoscopic papillary large balloon dilation versus sphincterotomy

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World Journal of Gastroenterology 2009年第34期15卷 4298-4304页

作者： Hyun Gun Kim Young Koog Cheon Young Deok Cho jong ho moon Do Hyun Park Tae hoon Lee Hyun jong Choi Sang-Heum Park Joon Seong Lee moon Sung Lee Institute for Digestive Research Digestive Disease Center Soonchunhyang University College of Medicine

AIM： To compare small sphincterotomy combined with endoscopic papillary large balloon dilation （SES ＋ ELBD） and endoscopic sphincterotomy （EST） for large bile duct stones. METhoDS： We compared prospectively SES ＋ ELBD （group A, n = 27） with conventional EST （group B, n = 28） for the treatment of large bile duct stones （≥ 15 mm）. When the stone could not be removed with a normal basket, mechanical lithotripsy was performed. We compared the rates of complete stone removal with one session and application of mechanical lithotripsy. RESULTS： No significant differences were observed in the mean largest stone size （A： 20.8 mm, B： 21.3 mm）, bile duct diameter （A： 21.4 turn, B： 20.5 ram）, number of stones （A： 2.2, B： 2.3）, or procedure time （A： 18 min, B： 19 rain） between the two groups. The rates of complete stone removal with one session was 85% in group A and 86% in group B （P = 0.473）. Mechanical lithotripsy was required for stone removal in nine of 27 patients （33%） in group A and nine of 28 patients （32%, P = 0.527） in group ***： SES ＋ ELBD did not show significant benefits compared to conventional EST, especially for the removal of large （≥ 15 mm） bile duct stones.

关键词： Sphincterotomy Endoscopic Balloon dilatation Cholelithiasis Lithotripsy

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Endoscopic ultrasonography does not differentiate neoplastic from non-neoplastic small gallbladder polyps

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World Journal of Gastroenterology 2009年第19期15卷 2361-2366页

作者： Young Koog Cheon Won Young Cho Tae Hee Lee Young Deok Cho jong ho moon Joon Seong Lee Chan Sup Shim Institute for Digestive Research and Digestive Disease Center Soon Chun Hyang University College of Medicine657 Hannam-DongYongsan-KuSeoul 140-743South Korea

AIM： To assess the ability of endoscopic ultrasonography （EUS） to differentiate neoplastic from non- neoplastic polypoid lesions of the gallbladder （PLGs）.METhoDS： The uses of EUS and transabdominal ultrasonography （US） were retrospectively analyzed in 94 surgical cases of gallbladder polyps less than 20 mm in ***： The prevalence of neoplastic lesions with a diameter of 5-20 mm was 27.2% （10/58）; 22-15 mm, 25.4% （4/26）, and 16-20 mm, 50% （5/20）. The overall diagnostic accuracies of EUS and US for small PLGs were 80.9% and 63.9% （P 〈 0.05）, respectively. EUS correctly distinguished 12 （63.2%） of 19 neoplastic PLGs but was less accurate for polyps less than 1.0 cm （4/10, 40%） than for polyps greater than 1.0 cm （8/9, 88.9%）（P = 0.02）.CONCLUSION： Although EUS was more accurate than US, its accuracy for differentiating neoplastic from non-neoplastic PLGs less than 1.0 cm was low. Thus, EUS alone is not sufficient for determining a treatment strategy for PLGs of less than 1.0 cm.

关键词： Endoscopic ultrasonography Neoplasticlesion Polypoid gallbladder lesion

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Prevalence of clonorchiasis in patients with gastrointestinal disease: A Korean nationwide multicenter survey

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World Journal of Gastroenterology 2009年第1期15卷 86-94页

作者： ho Gak Kim Jimin Han Myung-Hwan Kim Kyu Hyun Cho Im Hee Shin Gwang Ha Kim Jae Seon Kim Jin Bong Kim Tae Nyeun Kim Tae Hyeon Kim Tae Hyo Kim Jae Woo Kim Ji Kon Ryu Young-Soo moon jong ho moon Sung Jae Park Chan Guk Park Sung-Jo Bang Chang Heon Yang Kyo-Sang Yoo Byung Moo Yoo Kyu Taek Lee Dong Ki Lee Byung Seok Lee Sang Soo Lee Seung Ok Lee Woo Jin Lee Chang Min Cho Young-Eun Joo Gab Jin Cheon Young Woo Choi Jae Bok Chung Yong Bum Yoon Department of Internal Medicine Catholic University of Daegu School of Medicine Daegu 705-718 South Korea Department of Internal Medicine Asan Medical Center University of Ulsan College of Medicine Seoul 138-736 South Korea Department of Medical Statistics Catholic University of Daegu School of Medicine Daegu 705-718 South Korea Department of Internal Medicine Pusan National University School of Medicine Busan 602-739 South Korea Department of Internal Medicine Korea University College of Medicine Seoul 136-705 South Korea Department of Internal Medicine Hallym University College of Medicine Chuncheon 200-704 South Korea Department of Internal Medicine Yeungnam University College of Medicine Daegu 705-717 South Korea Department of Internal Medicine Wonkwang University College of Medicine Iksan Jeonbuk 570-711 South Korea Department of Internal Medicine Gyeongsang National University School of Medicine Jinju Gyeongnam 660-702 South Korea Department of Internal Medicine Yonsei University Wonju College of Medicine Wonju Gangwon 220-701 South Korea Department of Internal Medicine Seoul National University College of Medicine Seoul 110-799 South Korea Department of Internal Medicine lnje University College of Medicine Seoul 139-713 South Korea Department of Internal Medicine Soonchunhyang University College of Medicine Bucheon Gyunggi 420-767 South Korea Department of Internal Medicine Inje University College of Medicine Busan 614-735 South Korea Department of Internal Medicine Chosun University College of Medicine Gwangju Jeonbuk 501-717 South Korea Department of Internal Medicine Ulsan University Hospital University of Ulsan College of Medicine Ulsan 681-714 South Korea Department of Internal Medicine Dongguk University College of Medicine Gyeongju Gyeongbuk 791-707 South Korea Department of Internal Medicine Hallym University College of Medicine Anyang Gyeonggi 431-070 South Korea Department of Internal Medicine Ajou University School of Medicine Suwon

AIM： To investigate prevalence of C/onorchis sinensis in patients with gastrointestinal symptoms, and the relation of the infection to hepatobiliary diseases in 26 hospitals in Korea. METhoDS： Consecutive patients who had been admitted to the Division of Gastroenterology with gastrointestinal symptoms were enrolled from March to April 2005. Of those who had been diagnosed with clonorchiasis, epidemiology and correlation between infection and hepatobiliary diseases were surveyed by questionnaire. RESULTS： Of 3080 patients with gastrointestinal diseases, 396 （12.9%） had clonorchiasis and 1140 patients （37.2%） had a history of eating raw freshwater fish. Of those with a history of raw freshwater fish ingestion, 238 （20.9%） patients had clonorchiasis. Cholangiocarcinoma was more prevalent in C. sinensis-infected patients than nonnfected patients [34/396 （8.6%） vs 145/2684 （5.4%）, P = 0.015]. Cholangiocarcinoma and clonorchiasis showed statistically significant positive cross-relation （P = 0.008）. Choledocholithiasis, cholecystolithiasis, cholangitis, hepatocellular carcinoma, and biliary pancreatitis did not correlate with clonorchiasis. CONCLUSION： Infection rate of clonorchiasis was still high in patients with gastrointestinal diseases in Korea, and has not decreased very much during the last two decades. Cholangiocarcinoma was related to clonorchiasis, which suggested an etiological role for the parasite.

关键词： Clonorchis sinensis Epidemiology Cholangiocarcinoma Korea Multicenter study Clonorchiasis

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Environmentally friendly hybrid coating prepared by electro-deposition method at various seawater conditions

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中国有色金属学会会刊：英文版 2009年第B09期19卷 110-113页

作者： Myeong-hoon LEE Kyung-Man moon jong-Do KIM Kang JUN Kwang-ho KIM Division of Marine System Engineering Korea Maritime University Dongsam-Dong Youngdo Busan 606-791 Korea National Core Research Center for Hybrid Materials Solution Pusan National University Busan 609-735 Korea

The formation mechanism of calcareous deposit films in seawater involves an increase in pH at the metal/solution interface due to cathodic reactions, a raised carbonate ion concentration at the interface and precipitation of inorganic deposits such as CaCO3, Mg(OH)2. Environmentally friendly hybrid calcareous deposit films were formed by an electrochemical technique on steel substrates in various solution environments. And the influence of dissolved gas on formation of calcareous deposit films was investigated by scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS) and X-ray diffractometry(XRD). Consequently, these results showed that formation of good overall calcareous deposited films by dissolved gas in seawater environments can be achieved by controlling the material composition and structure through effective use of electrochemical method.

关键词：海水混合环保电沉积扫描电子显微镜涂层制备溶液界面

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VANET Jamming and Adversarial Attack Defense for Autonomous Vehicle Safety

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Computers, Materials & Continua 2022年第5期71卷 3589-3605页

作者： Haeri Kim jong-moon Chung Department of Vehicle Convergence Engineering Yonsei UniversitySeoul03722Korea School of Electrical&Electronic Engineering Yonsei UniversitySeoul03722Korea

The development of Vehicular Ad-hoc Network(VANET)technology is helping Intelligent Transportation System(ITS)services to become a *** can use VANETs to communicate safety messages on the road(while driving)and can inform their location and share road condition information in ***,intentional and unintentional(e.g.,packet/frame collision)wireless signal jamming can occur,which will degrade the quality of communication over the channel,preventing the reception of safety messages,and thereby posing a safety hazard to the vehicle’s *** this paper,VANET jamming detection applying Support Vector Machine(SVM)machine learning technology is used to classify jamming and non-jamming *** analysis is based on two cases which include normal traffic and heavy traffic conditions,where the results show that the probability of packet dropping will increase when many vehicles are using the wireless channel *** using SVM classification,the most appropriate feature set applied in determining a jamming situation shows an accuracy of 98%or ***,more advanced jamming attacks need to be considered for preparation of more reliable and safer autonomous ITS *** research can use vehicular communication transmission and reception data based on selected published *** this paper,an additional adversarial defense algorithm using the Density-Based Spatial Clustering of Applications with Noise(DBSCAN)method is proposed,which assumes that evolutionary attacks of the jammer will attempt to confuse the trained *** simulation results show that applying DBSCAN can improve the accuracy by elimination of outliers before conducting classification testing.

关键词： Vehicle safety VANET jamming SVM adversarial defense

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Significance of age and comorbidity as prognostic indicators for patients with bladder cancer

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Asian Journal of Andrology 2010年第5期12卷 766-774页

作者： moon Soo Ha In ho Chang Department of Urology College of Medicine Chung-Ang University Seou1140-75 7 Korea

The aim of this study was to determine the impact that age and comorbidity status have on both overall and bladder cancer-specific survival of bladder cancer patients. We obtained medical information pertaining to a population of 528 patients with newly diagnosed bladder cancer from Chung-Ang University hospital cancer registry. The Adult Comorbidity Evaluation-27 （ACE-27） test, which has been previously validated in adult cancer patients, was used to assess comorbidity. We evaluated differences in the demographic and clinical characteristics of included patients, as well as differences in the treatments they received after categorizing them by age. The median age at the time of bladder cancer diagnosis of the entire cohort was 63 years, and the median follow-up time was 97 months. Of the 528 patients who were included in our study, 303 had at least one comorbid condition and 249 died during the follow-up period. When patients were stratified by age, we found that older patients had a higher proportion of severe comorbidities （P 〈 0.01） than younger patients, and that a lower proportion of them underwent radical cystec- tomy for invasive bladder cancer （IBC）（P 〈 0.01）. By multivariate analysis, we found that older age was predictive of lower overall survival （OS） and bladder cancer-specific survival （BCSS） rates among patients with superficial bladder cancer （SBC） and of lower OS rates among patients with IBC. We also found that moderate-severe comorbidity status and treatment through a bladder-conserving approach were predictive of lower OS and cancer-specific survival rates among patients with IBC. The disparity between overall deaths and bladder cancer deaths was shown in SBC and increased along with age and higher comorbidity. Age and comorbidity were found to be independent predictive factors of OS and BCSS among bladder cancer patients, and explained the disparity that we observed between overall bladder cancer-specific mortality rates.

关键词： age comorbidity neoplasm prognostic indicator urinary bladder

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Brain-derived neurotropic factor and GABAergic transmission in neurodegeneration and neuroregeneration

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Neural Regeneration Research 2017年第10期12卷 1733-1741页

作者： Jinwook Kim Sueun Lee Sohi Kang Sung-ho Kim jong-Choon Kim Miyoung Yang Changjong moon Departments of Veterinary Anatomy and Veterinary Toxicology College of Veterinary Medicine and BK21 PLUS Project TeamChonnam National University Department of Anatomy School of Medicine and Institute for Environmental ScienceWonkwang University

Neurotoxicity induced by stress,radiation,chemicals,or metabolic diseases,is commonly associated with excitotoxicity,oxidative stress,and *** pathological process of neurotoxicity induces neuronal death,interrupts synaptic plasticity in the brain,and is similar to that of diverse neurodegenerative *** models of neurotoxicity have revealed that clinical symptoms and brain lesions can recover over time via neuroregenerative ***,brain-derived neurotropic factor（BDNF） and gamma-aminobutyric acid（GABA）-ergic transmission are related to both neurodegeneration and *** review summarizes the accumulating evidences that suggest a pathogenic role of BDNF and GABAergic transmission,their underlying mechanisms,and the relationship between BDNF and GABA in neurodegeneration and *** review will provide a comprehensive overview of the underlying mechanisms of neuroregeneration that may help in developing potential strategies for pharmacotherapeutic approaches to treat neurotoxicity and neurodegenerative disease.

关键词： brain-derived neurotropic factor neurotoxicity gamma-aminobutyric acid-ergic transmission neurodegenerative diseases neural regeneration

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Development of XY scanner with minimized coupling motions for high-speed atomic force microscope

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Journal of Central South University 2011年第3期18卷 697-703页

作者： PARK jong-kyu moon Won-kyu Department of Mechanical Engineering Changwon National University Department of Mechanical Engineering Pohang Univer sity of Science and Technology

The design and fabrication processes of a novel scanner with minimized coupling motions for a high-speed atomic force microscope （AFM） were addressed. An appropriate design modification was proposed through the analyses of the dynamic characteristics of existing linear motion stages using a dynamic analysis program, Recurdyn. Because the scanning speed of each direction may differ, the linear motion stage for a high-speed scanner was designed to have different resonance frequencies for the modes, with one dominant displacement in the desired directions. This objective was achieved by using one-direction flexure mechanisms for each direction and mounting one stage for fast motion on the other stage for slow motion. This unsymmetrical configuration separated the frequencies of two vibration modes with one dominant displacement in each desired direction, and hence suppressed the coupling between motions in two directions. A pair of actuators was used for each axis to decrease the crosstalk between the two motions and give a sufficient force to actuate the slow motion stage, which carried the fast motion stage, A lossy material, such as grease, was inserted into the flexure hinge to suppress vibration problems that occurred when using an input triangular waveforrn. With these design modifications and the vibration suppression method, a novel scanner with a scanning speed greater than 20 Hz is achieved.

关键词： atomic force microscope scanner piezoelectric stack actuator crosstalk flexure hinge

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Quantum quasi-cyclic low-density parity-check error-correcting codes

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Chinese Physics B 2009年第10期18卷 4154-4160页

作者：李渊曾贵华 moon ho Leeb Laboratory of Coding and Communication Security Department of Electronic Engineering Shanghai Jiaotong University Institute of Information & Communication Department of Information & Communication EngineeringChonbuk National University

In this paper, we propose the approach of employing circulant permutation matrices to construct quantum quasicyclic （QC） low-density parity-check （LDPC） codes. Using the proposed approach one may construct some new quantum codes with various lengths and rates of no cycles-length 4 in their Tanner graphs. In addition, these constructed codes have the advantages of simple implementation and low-complexity encoding. Finally, the decoding approach for the proposed quantum QC LDPC is investigated.

关键词： quantum LDPC code quasi-cycliC circulant permutation matrix CSS code

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