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Material Characterization of Ni Base Alloy for Very High Temperature Reactor

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journal of Materials Science & Technology 2013年第12期29卷 1184-1190页

作者： Dong-jin Kim Gyeong-Geun Lee Dae jong Kim Su jin jeong Nuclear Materials Division Korea Atomic Energy Research Institute

The generation of highly efficient electricity and the production of massive hydrogen are possible using a very high temperature reactor （VHTR） among generation IV nuclear power plants. The structural material for an intermediate heat exchanger （IHX） among numerous components should be endurable at high temperature of up to 950 °C during long-term operation. Impurities inevitably introduced in helium as a coolant facilitate the material degradation by corrosion at high temperature. In the present work, the surface reactions available under controlled impure helium at 950 °C were investigated based on the thermodynamics and the corrosion tests were performed in a temperature range of 850-950 °C during 10-250 h for commercial Alloy 617 as a candidate material for an IHX. Moreover, the mechanical property and microstructure for nickel-based alloys fabricated in laboratory were evaluated as a function of the processing parameters such as hot rolling and heat treatment conditions. from the reaction rate constant obtained from an impure helium control system for a material evaluation, it was predicted that the outer oxide layer thickness, internal oxide depth, and carbide- depleted zone depth reach about 116, 600 and 1000 μm, respectively when Alloy 617 is exposed to an impure helium environment at 950 ~C for 20 years. for Ni-Cr-Co-Mo alloy, subsequent annealing and a combination of cold working and subsequent annealing following solution annealing caused increases in the grain boundary carbide coverage and size. The angular distribution of the grain boundary as well as the carbide distribution was also changed leading to a consequent improvement of the mechanical property at 950 °C in air.

关键词： Nickel base alloy Intermediate heat exchanger High temperature reactor Corrosion Mechanical property

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

Effects of Sn addition on the microstructure and mechanical properties of extruded Mg-Bi binary alloy

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journal of Magnesium and Alloys 2022年第3期10卷 920-931页

作者： Sang-Cheol jin jong Un Lee jongbin Go Hui Yu Sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566South Korea Department of Materials Science and Engineering Kyoto UniversityYoshida-honmachiSakyo-kuKyoto606-8501Japan School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130China

We investigated the effects of Sn addition on the microstructural characteristics and mechanical properties of an extruded Mg-Bi binary alloy by comparing Mg-5 Bi(B5)and Mg-5 Bi-4 Sn(BT54).Both the extruded alloys exhibit a partially recrystallized grain structure with a strong extrusion fiber texture and numerous Mg3Bi2 ***,the addition of Sn significantly decreases the average grain size of the extruded alloy from 123.9 to 75.2μ*** Sn solute atoms inhibit the activity of dislocation slip,which reduces the internal strain energy accumulated in the dynamically recrystallized(DRXed)grains during ***,this reduced strain energy leads to the decrease in the DRXed grain size owing to weakened grain growth during natural *** extruded BT54 alloy exhibits higher tensile strength and ductility than the extruded B5 *** improvement in the strength by the Sn addition is attributed to the combined effects of grain refinement,Sn solute atoms,and increased dislocation *** formation of{10-11}and{10-11}-{10-12}twins during tension is suppressed by the grain refinement,thereby improving the tensile elongation considerably.

关键词： Mg±Bi alloy Extrusion Dynamic recrystallization Microstructure Mechanical properties.

function of hepatocyte spheroids in bioactive microcapsules is enhanced by endogenous and exogenous hepatocyte growth factor

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Bioactive Materials 2023年第10期28卷 183-195页

作者： Kihak Gwon Daheui Choi jose mde Hoyos-Vega Harihara Baskaran Alan M.Gonzalez-Suarez Seonhwa Lee Hye jin Hong Kianna M.Nguyen Ether Dharmesh Go Sugahara Yuji Ishida Takeshi Saito Gulnaz Stybayeva Alexander Revzin Department of Physiology and Biomedical Engineering Mayo ClinicRochesterMNUSA Department of Chemical and Biomolecular Engineering Case Western Reserve UniversityClevelandOHUSA Biomedical Engineering Saint Louis UniversitySt.LouisMOUSA University of Southern Californi1 Keck School of MedicineDepartment of MedicineDivision of Gastrointestinal and Liver DiseasesLos AngelesCAUSA Research and Development Department PhoenixBioCo.LtdKagamiyam1Higashi-Hiroshim1Hiroshim1Japan USC Research Center for Liver Diseases Los AngelesCAUSA

The ability to maintain functional hepatocytes has important implications for bioartificial liver development,cell-based therapies,drug screening,and tissue *** approaches can be used to restore hepatocyte function in vitro,including coating a culture substrate with extracellular matrix(ECM),encapsulating cells within biomimetic gels(Collagen-or Matrigel-based),or co-cultivation with other *** paper describes the use of bioactive heparin-based core-shell microcapsules to form and cultivate hepatocyte *** microcapsules are comprised of an aqueous core that facilitates hepatocyte aggregation into spheroids and a heparin hydrogel shell that binds and releases growth *** demonstrate that bioactive microcapsules retain and release endogenous signals thus enhancing the function of encapsulated *** also demonstrate that hepatic function may be further enhanced by loading exogenous hepatocyte growth factor(HGf)into microcapsules and inhibiting transforming growth factor(TGf)-β1 ***,bioactive microcapsules described here represent a promising new strategy for the encapsulation and maintenance of primary hepatocytes and will be beneficial for liver tissue engineering,regenerative medicine,and drug testing applications.

关键词： Droplet microfluidics Bioactive microcapsules Hepatocyte spheroid Heparin Hepatocyte growth factor

Prevalence of-and risk factors for work disability in Dutch patients with inflammatory bowel disease

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World journal of Gastroenterology 2017年第46期23卷 8182-8192页

作者： Lieke M Spekhorst Bas Oldenburg Ad A van Bodegraven Dirk j de jong floris Imhann Andrea E van der Meulen-de jong Marieke j Pierik janneke C van der Woude Gerard Dijkstra Geert D'Haens Mark Lowenberg Rinse K Weersma Eleonora AM festen 无 Department of Gastroenterology and Hepatology University of Groningen and University Medical Centre Groningen Department of Genetics University of Groningen and University Medical Centre Groningen Department of Gastroenterology and Hepatology University Medical Center Utrecht Department of Gastroenterology and Hepatology VU University Medical Center Department of Gastroenterology and Hepatology University Medical Center St. Radboud Department of Gastroenterology and Hepatology Leiden University Medical Center Department of Gastroenterology and Hepatology University Medical Center Maastricht Department of Gastroenterology and Hepatology Erasmus Medical Center Department of Gastroenterology and Hepatology Amsterdam Medical Center Parelsnoer Institute and the Dutch Initiative on Crohn and Colitis

AIM To determine the prevalence of work disability in inflammatory bowel disease(IBD), and to assess risk factors associated with work *** for this retrospective cohort study, we retrieved clinical data from the Dutch IBD Biobank on july 2014, containing electronic patient records of 3388 IBD patients treated in the eight University Medical Centers in the Netherlands. Prevalence of work disability was assessed in 2794 IBD patients and compared with the general Dutch population. Multivariate analyses were performed for work disability(sick leave, partial and full disability) and long-term full work disability(> 80% work disability for > 2 years).RESULTS Prevalence of work disability was higher in Crohn's disease(CD)(29%) and ulcerative colitis(UC)(19%) patients compared to the general Dutch population(7%). In all IBD patients, female sex, a lower education level, and extra-intestinal manifestations, were associated with work disability. In CD patients, an age > 40 years at diagnosis, disease duration > 15 years,smoking, surgical interventions, and anti-TNfα use were associated with work disability. In UC patients, an age > 55 years, and immunomodulator use were associated with work disability. In CD patients, a lower education level(OR = 1.62, 95%CI: 1.02-2.58), and in UC patients, disease complications(OR = 3.39, 95%CI: 1.09-10.58) were associated with long-term full work *** The prevalence of work disability in IBD patients is higher than in the general Dutch population. Early assessment of risk factors for work disability is necessary, as work disability is substantial among IBD patients.

关键词： Inflammatory bowel disease Crohn’s disease Ulcerative colitis Work disability Health care costs

Magnetic-fluid microelectromechanical light modulator

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光学精密工程 2005年第5期13卷 542-547页

作者： SEO jong-wook WANG Xi-jun School of Electronic and Electrical Engineering Hongik University 72-1 Sangsu-dong Mapo-gu Seoul 121-791 Rep. Korea Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences Changchun 130033 China

A new microfluidic microelectromechanical light modulator using a magnetic fluid is introduced. The optical reflection from the device is modulated by applying an electric current into an electrode, which is enclosed by ferromagnetic thin films as in an inductive head for a magnetic data storage device. The magnetic field produced by the current exerts a magnetic force on the magnetic fluid and drives the fluid to cover the cell surface. The surface tension of the fluid provides a restoring force when the field is reduced. The actuation of the fluid is completed in about 12 ms for both thin-to-thick and thick-to-thin fluid film switchings by magnetic forces and surface tension forces, respectively. It was observed that the switching speed was almost independent of the driving current, and no considerable thermal effect were observed when driven by a current up to 100 mA.

关键词：微电子学光调节器磁性流动性 fPD MEMS 弯曲效应电极有限元法 fEM

Photo-Activated ferroptosis for Cancer Therapy: Advances, Challenges, and Prospects

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CCS Chemistry 2023年第8期5卷 1718-1736页

作者： Le Yu Yunjie Xu jong Seung Kim Department of Chemistry Korea UniversitySeoul 02841

ferroptosis, a recently identified form of non-apoptotic programmed cell death, has attracted significant attention in the field of cancer therapy due to its unique mechanism of cell death. To meet the demands of ferroptosis-mediated cancer treatment, several small molecule-based drugs have been reported for the implementation of ferroptosis. However, some cancer cells are inherently resistant to these drugs, and the lack of selectivity of these drugs against cancer cells can limit their clinical application. Recent advancements in light-mediated biomedical techniques offer a promising alternative for the development of ferroptotic therapy, that is photo-controlled activation of ferroptosis. In this review, we systematically summarize the current strategies for photo-controlled ferroptosis activation and detail analysis of the underlying mechanisms of those photo-controlled ferroptotic therapies. finally, we discuss the challenges associated with photo-activated ferroptosis and provide an outlook on the future developments in ferroptotic cancer therapy.

关键词： photo-activated ferroptosis ferroptoticcancer therapy photosensitizer photothermal agent photocatalyst

Isolation of cabbage exosome-like nanovesicles and investigation of their biological activities in human cells

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Bioactive Materials 2021年第12期6卷 4321-4332页

作者： jae Young You Su jin Kang Won jong Rhee Department of Bioengineering and Nano-Bioengineering Incheon National University Incheon22012Republic of Korea Division of Bioengineering Incheon National University Incheon 22012Republic of Korea

There are extensive studies on the applications of extracellular vesicles(EVs)produced in cell culture for therapeutic drug ***,large quantities of EVs are needed for in vivo applications,which requires high production costs and ***,the development of new EV sources is essential to facilitate their ***,plant-derived exosome-like nanovesicles are an emerging alternative for culture-derived *** now,however,few studies have explored their biological functions and ***,it is necessary to elucidate biological activities of plant-derived exosome-like nanovesicles and harness vesicles for biomedical ***,cabbage and red cabbage were used as nanovesicle sources owing to their easy ***,an efficient method for nanovesicle isolation from cabbage(Cabex)and red cabbage(Rabex)was ***,isolated nanovesicles were characterized,and their biological functions were *** Cabex and Rabex promoted mammalian cell proliferation and,interestingly,suppressed inflammation in immune cells and apoptosis in human keratinocytes and ***,therapeutic drugs were encapsulated in Cabex or Rabex and successfully delivered to human cells,demonstrating the potential of these vesicles as alternative drug delivery ***,the current results provide strong evidence for the wide application of Cabex and Rabex as novel therapeutic biomaterials.

关键词： Exosome-like nanovesicles Cabbage Inflammation Apoptosis Drug delivery

factors associated with mobile phone ownership and potential use for rabies vaccination campaigns in southern Malawi

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Infectious Diseases of Poverty 2020年第3期9卷 136-137页

作者： Orla Marron Gareth Thomas jordana LBurdon Bailey Dagmar Mayer Paul OGrossman frederic Lohr Andy DGibson Luke Gamble Patrick Chikungwa julius Chulu Ian GHandel Barend mde C Bronsvoort Richard jMellanby Stella Mazeri 不详 The Royal(Dick)School of Veterinary Studies Division of Veterinary Clinical StudiesThe University of EdinburghHospital for Small AnimalsEaster Bush Veterinary CentreRoslinMidlothianUK

Background:Rabies is a fatal but preventable viral disease,which causes an estimated 59000 human deaths globally every *** vast majority of human rabies cases are attributable to bites from infected domestic dogs and consequently control of rabies in the dog population through mass vaccination campaigns is considered the most effective method of eliminating the *** the WHO target of 70%vaccination coverage has proven challenging in low-resource settings such as Sub Saharan Africa,and lack of public awareness about rabies vaccination campaigns is a major barrier to their *** this study we surveyed communities in three districts in Southern Malawi to assess the extent of and socio-economic factors associated with mobile phone ownership and explore the attitudes of communities towards the use of short message service(SMS)to inform them of upcoming rabies vaccination ***:This study was carried out between 1 October–3 December 2018 during the post-vaccination assessment of the annual dog rabies campaign in Blantyre,Zomba and Chiradzulu districts,Malawi.1882 questionnaires were administered to households in 90 vaccination *** surveys gathered data on mobile phone ownership and use,and barriers to mobile phone access.A multivariable regression model was used to understand factors related to mobile phone ***:Most survey respondents owned or had use of a mobile phone,however there was evidence of an inequality of access,with higher education level,living in Blantyre district and being male positively associated with mobile phone *** principal barrier to mobile phone ownership was the cost of the phone *** feature phones were most common and few owned *** was commonly used and the main reason for not using SMS was *** to receiving SMS reminders about future rabies vaccination campaigns were ***:The study showed a majority of those surveyed have the use of

关键词： Rabies Mass vaccination mHealth Short message service