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Mechanical characteristics of fused cast basalt tube encased in steel pipe for protecting steel surface

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中国有色金属学会会刊：英文版 2009年第4期19卷 935-940页

作者： jee-Seok wANG Jong-Do KIM hee-Jong YOON Division of Mechanical and Information Engineering Korea Maritime University Division of Marine System Engineering Korea Maritime University Department of Research and Development Dongdo Basalt Industry Co.Ltd

Because of the various excellent characteristics of cast basalt materials,such as,anti-corrosion,anti-wearing,good hardness,high chemical stability,of which steel may not possess,the steel-basalt composite pipes are used in severe environments for compensating the defects of *** limit of bending moment with which steel-basalt composite pipe may safely endure was calculated and the limit curvature of the composite pipe in the safe range was *** application temperature of steel-basalt pipe was examined due to a different coefficient among basalt,mortar and mild steel.

关键词：玄武岩钢管表面保护机械特性包裹熔铸化学稳定性复合管

Single-atom Pd catalyst anchored on Zr-based metal-organic polyhedra for Suzuki-Miyaura cross coupling reactions in aqueous media

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Nano Research 2021年第2期14卷 486-492页

作者： Seongsoo Kim Seohyeon jee Kyung Min Choi Dong-Sik Shin Division of Chemical and Bioengineering Kangwon National UniversityGangwon-do 24341Republic of Korea Department of Chemical and Biological Engineering Sookmyung Womens University100 Cheongpa-ro 47-gilYongsan-guSeoul 04310Republic of Korea

The challenge for single-atom catalysts in various C-C cross coupling reaction exists in the development of solid supporting *** has been desired tofind a supporting material designed in molecular level to anchor a single-atom catalyst and provide high degree of dispersion and substrate access in aqueous ***,we prepared discrete cages of metal-organic polyhedra anchoring single Pd atom(MOP-BPY(Pd))and successfully performed a Suzuki-Miyaura cross coupling reaction with various substrates in aqueous *** was revealed that each tetrahedral cage of MOP-BPY(Pd)has 4.5 Pd atoms on average and retained its high degree of dispersion up to 3 months in *** coupling efficiencies of the Suzuki-Miyaura cross coupling reaction exhibited more than 90.0%for various substrates we have tested in the aqueous media,which is superior to those of the molecular Pd complex and metal-organic framework(MOF)anchoring Pd ***,MOP-BPY(Pd)was successfully recovered and recycled without performance degradation.

关键词： metal-organic polyhedra Suzuki-Miyaura cross coupling reaction structure characterization aqueous phase reaction high-degree of dispersion

Systematic approaches to improving the performance of polyoxometalates in non-aqueous redox flow batteries

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Journal of Energy Chemistry 2020年第11期29卷 115-124页

作者： Yuan Cao jee-Jay J.Chen Mark A.Barteau Department of Chemical Engineering University of MichiganAnn ArborMI 48109United States Applied Materials 14J Fuller RoadAlbanyNY 12203United States Department of Chemical Engineering and Department of Chemistry Texas A&M UniversityCollege StationTX 77843United States

Polyoxometalates have been explored as multi-electron active species in both aqueous and non-aqueous redox flow batteries. Although non-aqueous systems in principle offer a wider voltage window for redox flow battery operation, realization of this potential requires a judicious choice of solvent as well as polyoxometalate properties. we demonstrate here the superior performance of N,N-dimethylformamide(DMF)compared to acetonitrile as a solvent for redox flow batteries based on Li3PMo12O40. This compound displays two 1-electron transfers in acetonitrile but can access an extra quasi-reversible 2-electron redox process in DMF. A cell containing 10 mM solution of Li3PMo12O40 in DMF produced a cell voltage of 0.7 V with 2-electron transfers(State of Charge = 60%) and showed a good cyclability. As a means to boost energy density, operation of the redox flow battery at a higher concentration of 0.1 M Li3PMo12O40 produced cells with cell voltage of 0.6 V in acetonitrile and a cell voltage of 1.0 V in DMF;both showed excellent coulombic efficiencies of more than 90% over the course of 30 cycles. Energy density was also increased by employing an asymmetric cell with different polyoxometalates on each side to extend cell ***6P2w18O62 exhibited 3 quasi-reversible 2-electron transfers in the potential range between-2.05 V and-0.5 V vs. Ag/Ag+. 10 mM Li6P2w18O62/Li3PMo12O40 in DMF produced a cell with cell voltage of 1.3 V involving 4-electron transfers(State of Charge = 50%) with coulombic efficiency of nearly 100% and energy efficiency of nearly 70% throughout the test with more than 20 cycles. These promising results demonstrate proof-of-concept approaches to improving the performance of polyoxometalates in non-aqueous redox flow batteries.

关键词： Polyoxometalate Energy density Redox flow battery Non-aqueous battery Cyclic voltammetry Bulk electrolysis

what physicians should know about the management of chronic hepatitis B in children: East side story

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world Journal of Gastroenterology 2014年第13期20卷 3582-3589页

作者： hun-jee Choe Byung-ho Choe Seoul National University College of Medicine Seoul 110-799South Korea Department of Pediatrics Kyungpook National University School of MedicineDaegu 700-721South Korea

Understanding the natural course of chronic hepatitis B virus(hBV)infection is very important for the management and treatment of chronic hepatitis B in *** on treatment guidelines,the management of hBV carriers and treatment of active hepatitis have been advancing and resulted in increased survival,as well as decreased risks of complications such as liver cirrhosis and hepatocellular *** of a continuing medical education(CME)program for primary physicians becomes an important responsibility of pediatric *** could prevent misdiagnosis and unnecessary treatment that could lead to liver complications or antiviral *** addition,education of patients and their parents is necessary to achieve better therapeutic outcomes.

关键词： hepatitis B virus Natural course Diagnosis Treatment Lamivudine Resistance

what is the appropriate strategy for diagnosing NAFLD using ultrasonography in obese children?

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world Journal of Pediatrics 2017年第3期13卷 248-254页

作者： jee hyun Lee Su Jin Jeong Department of Pediatrics Ansan HospitalKorea University Medical CenterCollege of MedicineKorea University Department of Pediatrics Bundang CHA Medical CenterCHA University School of MedicineKorea

Background:The aim of this study is to identify obese children who are candidates for a potential diagnosis of non-alcoholic fatty liver disease (NAFLD).Methods:we enrolled 242 obese children (122 boys and 120 girls) aged 7-16 years who were examined with abdominal ultrasonography in our pediatric obesity *** compared patients in the normal group with those in the NAFLD group (mild disease,moderate to severe disease) and identified the optimal anthropometric parameters among height,weight,body mass index (BMI),waist circumference,hip circumference,waist to height ratio (whtR),and waist to hip ratio to predict NAFLD using a receiver operating characteristic curve *** also investigated risk factors associated with NAFLD for the anthropometric parameters and the biochemical model using logistic ***:The high-and low-risk groups for hepatic steatosis relative to a whtR of 0.56 as the standard point showed significant differences in hepatic steatosis severity grade (Phip circumference (P=0.090),aspartate aminotransferase (Phe triglyceride to high-density lipoprotein (hDL) cholesterol ratio (P=0.006).Risk factors for hepatic steatosis on logistic regression analysis were male sex (odds ratio:3.68,95% confidence interval:1.76-7.70),whtR >0.56 (2.25,1.05-4.81),and waist circumference >90th percentile (20.22,9.21-44.36) in the anthropometric parameter model and elevated alanine aminotransferase levels (boys >25.8 U/L,girls >22.1 U/L) (6.93,2.52-19.03),hypertriglyceridemia (>110 mg/dL) (3.80,1.23-11.75),and triglyceride to hDL cholesterol ratio >3 (9.23,2.95-8.83) in the biochemical parameter ***:A diagnostic approach to hepatic steatosis is recommended as part of the proper screening and stratification of risk factors in obese *** is a simple and convenient method of effectively identifying obese children who are candidates for hep

关键词： hepatic steatosis non-alcoholic fatty liver disease obesity waist-to-height ratio

Inactivation of Salmonella Newport on blueberries by treatment with chlorine dioxide gas and its effect on blueberry qualities

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Food Bioscience 2023年第3期53卷 1960-1966页

作者： Eungyeong Kim jee-hoon Ryu hoikyung Kim wonkwang Food Institute 460 Iksan-daeroIksanJeonbuk54538Republic of Korea Department of Biotechnology College of Life Sciences and BiotechnologyKoreaUniversity145 Anam-roSeongbuk-kuSeoul 02841Republic of Korea Department of Food and Nutrition College of Agriculture and Food SciencesWonkwang University460 Iksan-daeroIksanJeonbuk 54538Republic of Korea

The purpose of this study was to use chlorine dioxide(ClO_(2))gas to inactivate Salmonella Newport on blueberries and observe quality changes of blueberries as affected by the *** inoculated with *** were treated with ClO_(2) gas for 10 h ClO_(2) gas was generated from either 1 or 2 mL of ClO_(2) solution dropped in a sealed container and the container was hold at 12℃ or 25℃.within 30 min,Salmonella populations on blueberries treated with ClO_(2) gas,regardless of treatment temperature and amount of ClO_(2) solution,reduced below the detection limit(1.7 log CFU/sample)and the organism was eliminated within 30 min when 1 mL of ClO_(2) solution was used to generate gas at 25℃.After the ClO_(2) gas treatment,blueberries were analyzed with an electronic *** of untreated and ClO_(2)-gas treated blueberries are composed of 12 and 11 color codes,*** of the color codes,7 codes of both blueberries in control and treatment groups are the ***_(2) gas treatment did not cause significant changes in hunter’s L,a,and b-value of ***(g)of blueberries treated with ClO_(2) gas for 30 min significantly increased;however final values were not significantly different from the values of untreated *** a result of this study,the ClO_(2) gas successfully reduced *** on blueberries without significant changes in their color and hardness.

关键词： Chlorine dioxide Salmonella Newport Blueberry Antimicrobial activity

Economic Assessment of Standby Diesel Generator for Peak Reduction in Commercial and Industrial Buildings:A Case Study in Malaysia

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Journal of Electronic Science and Technology 2017年第4期15卷 400-406页

作者： Kein huat Chua Yun Seng Lim jee Xiong Chew Universiti Tunku Abdul Rahman Cheras 43000 Malaysia

This paper outlines the barriers and potential benefits of using standby diesel generators in mitigating the peak demands for commercial and industrial customers. The feasibility of utilizing the standby diesel generators to reduce the electricity bills for customers is carried out by using the hybrid optimization model for electric renewable(hOMER)software. The size of the standby diesel generator and its operational duration are determined based on the lowest cost of electricity obtained from the evaluations. The economic assessments demonstrate that there is potential to reduce the electricity bills for commercial and industrial customers under the existing fuel price and tariffs. The commercial customers under the tariff C2 have the highest potential to save their electricity bills with the use of standby diesel generators for peak reduction. This study demonstrates the potential of the standby diesel generators in peak reduction.

关键词： Commercial and industrial customers cost of electricity hybrid optimization model for electric renewable(hOMER) peak reduction standby diesel generator

Development of 3D bicontinuous metal-intermetallic composites through subsequent alloying process after liquid metal dealloying

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Journal of Magnesium and Alloys 2023年第11期11卷 4274-4281页

作者： jee Eun Jang Jihye Seong Soo-hyun Joo Sung hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Department of Materials Science and Engineering Dankook UniversityCheonan 31116Republic of Korea

This study presents a novel process for the fabrication of metal-intermetallic composites with a 3D bicontinuous structure, achieved through a combination of liquid metal dealloying(LMD) and subsequent alloying. Initially, porous Ti structures are produced using the LMD process, followed by immersion in a molten Mg-3Al(wt%) metal. Due to the higher thermodynamic miscibility of Al with Ti compared to Mg, the concentration of Al in the Ti matrix increases as the immersion time increases. This results in a sequential phase transition within the Ti matrix: α-Ti → Ti_(3)Al → Ti Al. The phase transition considerably affects the hardness and strength of the composite material,with the Mg-Ti_(3)Al-Ti Al composite exhibiting a maximum hardness nearly twice as high as that of the conventional Mg-Ti composite. This innovative process holds potential for the development of various bicontinuous metal-intermetallic composites.

关键词： Liquid metal dealloying Subsequent alloying Metal–intermetallic composite 3D bicontinuous structure hardness

Imidazole linker‐induced covalent triazine framework-ZIF hybrids for confined hollow carbon super‐heterostructures toward a long‐life supercapacitor

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Carbon Energy 2023年第10期5卷 25-39页

作者： Madagonda MVadiyar Ji‐Young Kim jee‐hwan Bae Kyung‐wan Nam Department of Energy and Materials Engineering Dongguk UniversitySeoulSouth Korea Advanced Analysis&Data Center Korea Institute of Science and Technology(KIST)SeoulSouth Korea Advanced Energy and Electronic Materials Research Center Dongguk UniversitySeoulSouth Korea

Carbon super-heterostructures with high nitrogen contents from the covalent hybrid precursors of covalent triazine frameworks(CTFs)and zeolitic imidazolic frameworks(ZIFs)are scarcely explored because of CTF's ordered structure and toxic superacid that dissolves or destabilizes the metal *** solve this problem,herein,we report a straightforward two-step pathway for the covalent hybridization of disordered CTF(d–CTF)–ZIF composites via preincorporation of an imidazole(IM)linker into ordered CTFs,followed by the imidazole-site-specific covalent growth of *** carbonization of these synthesized d–CTF−IM−ZIF hybrids results in unique hollow carbon super-heterostructures with ultrahigh nitrogen content(>18.6%),high specific surface area(1663m^(2)g^(−1)),and beneficial trace metal(Co/Zn NPs)contents for promoting the redox *** proof of concept,the obtained carbon super-heterostructure(Co–Zn–NC_(SNh)–800)is used as a positive electrode in an asymmetric supercapacitor,demonstrating a remarkable energy density of 61wh kg^(−1)and extraordinary cyclic stability of 97%retention after 30,000 cycles at the cell *** presynthetic modifications of CTF and their covalent hybridization with ZIF crystals pave the way toward new design strategies for synthesizing functional porous carbon materials for promising energy applications.

关键词： asymmetric supercapacitor defective covalent triazine frameworks hollow carbon superheterostructures linker defect