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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

Role of ascites adenosine deaminase in differentiating between tuberculous peritonitis and peritoneal carcinomatosis

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World Journal of Gastroenterology 2012年第22期18卷 2837-2843页

作者： Seung Joo Kang Ji Won kim jee hyun Baek Se hyung kim Byeong Gwan kim Kook Lae Lee Ji Bong Jeong Yong Jin Jung Joo Sung kim hyun Chae Jung In Sung Song Department of Internal Medicine and Liver Research Institute Seoul National University College of Medicine Department of Internal Medicine Seoul National University Boramae Hospital Department of Radiology Seoul National University College of Medicine

AIM： To investigate the usefulness of tumor markers and adenosine deaminase in differentiating between tuberculous peritonitis （TBP） and peritoneal carcinoma- tosis （PC）. METHODS： A retrospective analysis of data was per- formed on consecutive patients who underwent perito- neoscopic and abdominal computed tomography （CT） evaluations. Among 75 patients at the Seoul National University Hospital from January 2000 to June 2010 who underwent both tests, 27 patients （36.0%） and 25 patients （33.3%） were diagnosed with TBP and PC, re- spectively. Diagnosis was confirmed by peritoneoscopic biopsy. RESULTS： Serum c-reactive protein （7.88：1：6.62 mg/ dL vs 3.12 ＋ 2.69 mg/dL, P = 0.01）, ascites adenos- ine deaminase （66.76：1：32.09 IU/L vs 13.89 ：l： 8.95 IU/L, P 〈 0.01）, ascites lymphocyte proportion （67.77 ：1： 23.41% vs 48.36 ＋ 18.78%, P 〈 0.01）, and serum- ascites albumin gradient （0.72 ＋ 0.49 g/dL vs 1.05 ＋ 0.50 g/dL, P = 0.03） were significantly different be- tween the two groups. Among tumor markers, serum and ascites carcinoembryonic antigen, serum carbohy- drate antigen 19-9 showed significant difference be- tween two groups. Abdominal CT examinations showed that smooth involvement of the parietal peritoneum was more common in the TBP group （77.8% vs 40.7%） whereas nodular involvement was more common in the PC group （14.8% vs 40.7%, P = 0.04）. From receiver operating characteristic （ROC） curves ascites adeno- sines deaminase （ADA） showed better discriminative capability than tumor markers. An ADA cut-off level of 21 IU/L was found to yield the best results of differ- ential diagnosis; sensitivity, specificity, positive predic- tive value, and negative predictive value were 92.0%, 85.0%, 88.5% and 89.5%, respectively. CONCLUSION： Besides clinical and radiologic findings, ascitic fluid ADA measurement is helpful in the differen- tial diagnosis of TBP and PC.

关键词： Tuberculous peritonitis Peritoneal carcino-matosis, Adenosine deaminase, Peritoneoscopy

Decomposition of Nitrogen Trifluoride Using Low Power Arc Plasma

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Plasma Science and Technology 2013年第9期15卷 923-927页

作者： jee-Hun KO Sooseok CHOI hyun-Woo PARK Dong-Wha PARK Department of Chemical Engineering and Regional Innovation Center for Environmental Technology of Thermal Plasma (RIC-ETTP)INHA University253 Yonghyun-dongNam-guIncheon 402-751Republic of Korea Department of Environmental Chemistry and Engineering Tokyo Institute of Technology 4259-G1-22Nagatsuta-choMidori-kuYokohama 226-8502Japan

The low power arc plasma is characterized by extremely high enthalpy and temper- ature and it is easy to generate and control, and thus thermal decomposition process based on the plasma torch is receiving a great attention for decomposing non-degradable greenhouse gases. In order to elevate the economic feasibility, the effects of input power, waste gas flow rate and additive gases on the destruction and removal efficiency （DRE） of NF3 are examined. Specific energy density （SED） deceases as the flow rate increases, and accordingly, the DRE is reduced. The DRE is basically determined by the specific energy density. The highest DRE of NF3 was 97% for the waste gas flow rate of 100 L/min at a low input power level of 2 kW with the help of hydrogen additional gas. The inlet and outlet concentration of NF3 was analyzed using Fourier transform infrared spectroscopy （FT-IR） for DRE of NF3 evaluation. As a result, large amount of NF3 can be efficiently decomposed by low power arc plasma systems.

关键词： arc plasma decomposition nitrogen trifluoride

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

Clinical features of gastric adenoma detected within 3 years after negative screening endoscopy in Korea

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Gastroenterology Report 2023年第1期11卷 406-411页

作者： hyun Young kim Department of Internal Medicine Seoul National University Bundang HospitalSeongnam-siGyeonggi-doKorea

Background:Early detection and management of gastric adenoma are important for preventing gastric *** present study aimed to evaluate the predictors of missed gastric adenoma on screening endoscopy in Korea and identify the risk factors associated with interval precancerous gastric ***:All cases of gastric adenomas diagnosed via screening endoscopy between 2007 and 2019 were *** them,those who had undergone endoscopy within 3 years were included in the present *** gastric adenoma was defined as gastric adenoma diagnosed within 3 years after negative screening ***:In total,295 cases of gastric adenoma were *** these,95(32.2%)were missed gastric adenoma cases(mean age,60.6 years;average interval between final and index endoscopies,12.6months);the remaining 200(67.8%)were newly detected adenoma *** analysis revealed thatmale sex,endoscopist experience,observation time,and presence of gastric intestinalmetaplasia(pathologically proven)were associated with missed gastric *** analysis revealed that gastric intestinal metaplasia(odds ratio[OR],2.736;95%confidence interval[CI],1.320–5.667;P=0.007)and shorter observation time of the index screening endoscopy(B,0.011;OR,0.990;95%CI,0.986–0.993;P<0.001)were independent risk factors for missed gastric *** optimal cut-off for the observation time for detecting gastric adenoma was 3.53minutes(area under curve,0.738;95%CI,0.677–0.799;P<0.001).Conclusions:Gastric intestinal metaplasia is an indication of missed gastric ***,careful inspection of gastric mucosa with gastric intestinal metaplasia and proper observation time can lower the possibility of missing the gastric adenoma during screening.

关键词： gastric adenoma screening endoscopy gastric intestinal metaplasia observation time

Hyperreflective photonic crystals created by shearing colloidal dispersions at ultrahigh volume fraction

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Microsystems & Nanoengineering 2024年第1期10卷 161-173页

作者： Minji kim Jong Bin kim Shin-hyun kim Department of Chemical and Biomolecular Engineering Korea Advanced Institute of Science and Technology(KAIST)Daejeon 34141Republic of Korea

Colloidal crystallization serves as one of the most economic and scalable production methods for photonic ***,insufficient optical performance,nonuniformity and low reproducibility remain challenges for advanced high-value *** this study,we optimally formulate a photocurable dispersion of silica particles and apply shear flow to unify the orientation of the colloidal crystals,ensuring high optical performance and *** silica particles experience strong repulsion at ultrahigh volume fractions of 50%but demonstrate low mobility,leading to polycrystalline *** shear flow to the dispersions allows the silica particles to rearrange into larger crystalline domains with a unidirectional orientation along the *** shear-induced structural change produces absolute reflectivity at the stopband as high as 90%and a high transparency of 90%at off-resonant wavelengths with minimal diffusive ***,the strong interparticle repulsion ensures a uniform volume fraction of particles throughout the dispersion,reducing deviations in the optical *** intricately micropattern the photocurable dispersions using ***,the photonic films and patterns can be stacked to form multiple layers,displaying mixed structural colors and multiple reflectance peaks without sacrificing *** superior photonic materials hold promise for various optical applications,including optical components and anticounterfeiting patches.

关键词： properties. dispersion reflectivity

Male metaplastic breast cancer with poor prognosis:A case report

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World Journal of Clinical Cases 2022年第15期10卷 4964-4970页

作者： hyun Yul kim Seungju Lee Dong-il kim Chang Shin Jung jee Yeon kim Kyung Jin Nam Ki Seok Choo Youn Joo Jung Department of Surgery Pusan National University Yangsan HospitalPusan National University School of MedicineGyeongnam 50612South Korea Department of Pathology Pusan National University Yangsan HospitalPusan National University School of MedicineGyeongnam 50612South Korea Department of Radiology Pusan National University Yangsan HospitalPusan National University School of MedicineGyeongnam 50612South Korea

BACKGROUND Metaplastic breast cancer(MBC)is a rare subtype of breast *** constitute less than 1%of breast cancer cases and are much rarer in *** are few reports of MBC because of its ***,an aggressive type of cancer,is refractory to common treatment modalities of breast cancer and has a poor *** SUMMARY We report a case of MBC in a 78-year-old *** visited our clinic with a palpable mass on the left breast with no masses in the axillary *** had previously undergone robot-assisted laparoscopic radical prostatectomy for prostate cancer,but there was no family history of *** breast mass was visible on ultrasonography,mammography,and magnetic resonance imaging,and chest computed tomography revealed a lung mass in the posterior basal segment of the right lower *** patient was diagnosed with metaplastic carcinoma on core needle biopsy with lung *** mastectomy with sentinel lymph node biopsy and video-assisted segmentectomy of the right lung was ***,multiple metastases appeared 3 mo after surgery in the brain,chest,and abdomen,and the patient died 5 mo after the initial *** MBC is an aggressive and extremely rare breast cancer *** case reports are needed to determine the optimal treatment.

关键词： Breast neoplasm Male Triple-negative breast cancer Metaplastic breast cancer Adjuvant treatment Case report

Flow Characteristics in Compact Thermal Spray Coating Systems with Minimum Length Nozzle

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Plasma Science and Technology 2009年第5期11卷 550-554页

作者： Seung-hyun kim Youn-Jea kim School of Mechanical Engineering Sungkyunkwan University

In this study, numerical analysis is performed to adopt the equivalence ratio on the high velocity oxygen fuel （HVOF） thermal spray coating systems equipped with a minimum length nozzle. The analysis is applied to investigate the axisymmetric, steady-state, turbulent, and chemically combusting flow both within the torch and in a free jet region between the torch and the substrate to be coated. The combustion is modeled using a single-step and eddy-dissipation model which assumes that the reaction rate is limited by the turbulent mixing rate of the fuel and oxidant. As the diameter of the nozzle throat is increased, the location of the Mach shock disc moves backward from the nozzle exit. As the throat diameter and the divergent portion are 6 mm and 8 mm, respectively, the pressure in the HVOF system is the lowest at the chamber and the expanding gas is steadily maintained with both high velocity and high temperature for different equivalence ratios. Thus, relatively minor amendments of the equivalence ratio and the geometry of HVOF can lead to improved control over coating characteristics.

关键词： minimum length nozzle HVOF equivalence ratio

Copper telluride with manipulated carrier concentrations for high-performance solid-state thermoelectrics

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Journal of Materials Science & Technology 2022年第34期129卷 190-195页

作者： hyun Ju Dabin Park Minsu kim Jooheon kim G.W.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA School of Chemical Engineering&Materials Science Chung-Ang UniversitySeoul 06974Republic of Korea Department of Intelligent Energy and Industry Graduate SchoolChung-Ang UniversitySeoul 06974Republic of Korea Department of Advance Materials Engineering Chung-Ang UniversityAnseong 17546Republic of Korea

This study proposed a strategy for effectively diminishing the carrier concentration in Cu_(2)Te by introducing graphene sheets,Based on thermoelectric property measurements and single parabolic band modeling,the incorporated graphene effectively reduced the carrier concentration,not only enhancing the thermoelectric performance of the Cu_(2)Te/graphene composite but also substantially improving its figure of merit up to ~1.47 at 1000 K,which is 268% higher than that of pristine Cu_(2)Te,This study gives an insight into the control of carrier concentration and thermoelectric properties in Cu_(2)Te,and it could be extended to other copper chalcogenides for excellent thermoelectrics.

关键词： Thermoelectric Copper telluride Graphene Carrier concentration Single parabolic band model