检索结果-南通市图书馆

Optimization of thermoelectric properties of n-type Bi_2(Te,Se)_3 with optimizing ball milling time

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2018年第4期37卷 351-359页

作者： Ji-Hee son min-Wook Oh Bong-seo Kim Su-Dong Park Thermoelectric Conversion Research Center Korea Electrotechnology Research Institute Department of Materials Science and Engineering Hanbat National University

The thermoelectric properties at elevated temperature were investigated for n-type Bi2（Te,Se）3 which is obtained from ball milling processed powder with various milling times. Electrical properties such as electrical resistivity and Seebeck coefficient are clearly dependent on milling time, in which the carrier concentration is attributed to the change of the electrical properties. The concentrations of the defects are also varied with the ball milling time, which is the origin of the carrier concentration variation. Even though finer grain sizes are obtained after the long ball milling time, the temperature dependence of the thermal conductivity is not solely understood with the grain size, whereas the electrical contribution to the thermal conductivity should be also considered. The highest figure of merit value of ZT = 0.83 is achieved at 373 K for the optimized samples, in which ball milling time is 10 h. The obtained ZT value is 48% improvement over that of the 0.5-h sample at 373 K.

关键词： Thermoelectric properties Ball milling Bi2Te3 Seebeck coefficient Grain size Thermalconductivity

Controllable substitutional vanadium doping in wafer-scale molybdenum disulfide films

在线全文

学校读者我要写书评

暂无评论

Nano Research 2023年第2期16卷 3415-3421页

作者： Jihyung seo Eunbin son Jiha Kim Sun-Woo Kim Jeong min Baik Hyesung Park Department of Materials Science and Engineering Graduate School of Semiconductor Materials and Devices EngineeringGraduate School of Carbon NeutralityLow Dimensional Carbon Materials CenterUlsan National Institute of Science and TechnologyUlsan 44919Republic of Korea School of Advanced Materials Science and Engineering Sungkyunkwan University(SKKU)Suwon 16419Republic of Korea SKKU Institute of Energy Science and Technology Sungkyunkwan UniversitySuwon 16419Republic of Korea

Substitutional atomic doping of transition metal dichalcogenides(TMDs)in the chemical vapor deposition(CVD)process is a promising and effective strategy for modifying their physicochemical ***,the conventional CVD method only allows narrow-range modulation of the dopant concentration owing to the low reactivity of the ***,the growth of wafer-scale monolayer TMD films with high dopant concentrations is much more ***,we report a facile doping approach based on liquid precursor-mediated CVD process for achieving high vanadium(V)doping in the MoS_(2)lattice with excellent doping uniformity and *** lateral growth of the host MoS_(2)lattice and the reactivity of the V precursor were simultaneously improved by introducing an alkali metal halide as a reaction *** metal halide promoter enabled the wafer-scale synthesis of V-incorporated MoS_(2)monolayer film with excessively high doping *** excellent wafer-scale uniformity of the highly V-doped MoS_(2)film was confirmed through a series of microscopic,spectroscopic,and electrical analyses.

关键词： doping concentration reaction promoter substitutional doping transition metal dichalcogenides wafer-scale growth

Effect of internal sloshing on added resistance of ship

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2017年第1期29卷 13-26页

作者： min-Guk seo Yonghwan Kim Dong-min Park Korea Research Institute of Ships and Ocean Engineering DaejeonKorea Department of Naval Architecture and Ocean Engineering Seoul National UniversitySeoulKorea

The motion responses of ships carrying liquid cargo are affected not only by external wave excitation, but also by internal sloshing-induced forces and moments. Sloshing flow is coupled with the ship motion. This means the added resistance in waves may change when sloshing occurs inside the tank of the ship. In this study, the motion responses and added resistance of a ship, coupled with the sloshing-induced internal forces and moments are considered by using the linear potential theory. The three-dimensional Rankine panel method, in which the physical quantities are represented by using B-spline basis function, is applied. The sloshing flow of inner tanks is also simulated by Using the Rankine panel method and linearized boundary value problem. To study the added resistance, a near-field method, which integrates the second-order pressure on a body surface, is applied. The model ship is a blunt modified Wigley model with two inner tanks. Numerical results obtained without inner tanks are compared with the experimental data, and then the effect of filling ratio of inner tanks on ship motion and added resistance are observed. The components that induce added resistance are examined, and the effects of surge motion on sloshing flow and added resistance are briefly considered. This study shows that the sloshing flow inside the inner tanks may significantly influence not only the motion responses, but also added resistance, especially, when the incident wave frequency approaches the resonance frequency of the sloshing flow.

关键词： Added resistance sloshing seakeeping coupled effect Rankine panel method

Aligned Ion Conduction Pathway of Polyrotaxane‑Based Electrolyte with Dispersed Hydrophobic Chains for Solid‑State Lithium–Oxygen Batteries

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2025年第2期17卷 169-186页

作者： Bitgaram Kim Myeong‑Chang Sung Gwang‑Hee Lee Byoungjoon Hwang Sojung seo Ji‑Hun seo Dong‑Wan Kim Department of Materials Science and Engineering Korea University145 Anam‑RoSeongbuk‑GuSeoul 02841Republic of Korea School of Civil Environmental and Architectural EngineeringKorea University145 Anam‑RoSeongbuk‑GuSeoul 02841Republic of Korea Materials Science and Chemical Engineering Center Institute for Advanced Engineering(IAE)Yongin 17180Republic of Korea

A critical challenge hindering the practical application of lithium–oxygen batteries(LOBs)is the inevitable problems associated with liquid electrolytes,such as evaporation and safety *** study addresses these problems by proposing a modified polyrotaxane(mPR)-based solid polymer electrolyte(SPE)design that simultaneously mitigates solvent-related problems and improves ***-SPE exhibits high ion conductivity(2.8×10^(−3)S cm^(−1)at 25℃)through aligned ion conduction pathways and provides electrode protection ability through hydrophobic chain *** this mPR-SPE into solid-state LOBs resulted in stable potentials over 300 *** situ Raman spectroscopy reveals the presence of an LiO_(2)intermediate alongside Li_(2)O_(2)during oxygen *** situ X-ray diffraction confirm the ability of the SPE to hinder the permeation of oxygen and moisture,as demonstrated by the air permeability *** present study suggests that maintaining a low residual solvent while achieving high ionic conductivity is crucial for restricting the sub-reactions of solid-state LOBs.

关键词： Solid polymer electrolyte Lithium-oxygen batteries Polyrotaxane ion conductivity Hydrophobic chain

Effect of friction on the contact stress of a coated polymer gear

在线全文

学校读者我要写书评

暂无评论

Friction 2020年第6期8卷 1169-1177页

作者： Su-min BAE Kuk-Jin seo Dae-Eun KIM Department of Mechanical Engineering Yonsei UniversitySeoul 03722Republic of Korea

Polymer gears are used extensively in various ***,durability issues have been emerging because of friction at gear tooth contact *** extend the lifetime of polymer gears,a low-frictional coating has been considered as a possible *** this study,a finite element simulation method was performed to investigate the contact stress between a pair of coated polymer *** simulation included various friction coefficients(COFs)for studying the effects of friction during the *** results revealed that the friction causes the contact stress to shift over the roll angle,which is attributed to the direction of the sliding friction based on a free-body *** also investigated the effects of coating and found that a thin coating has little effect on the bulk deformation behavior of the ***,the stress distribution in the coating at the pitch point was investigated as the COF *** zero friction,three notable stress regions were observed:1)the center of the surface,2)the end of the contact,and 3)the overall contact *** COF was increased in the micro-slip region of the contact interface,both tensile and compressive stresses in the coating *** study provides significant aid to engineers for understanding the stress response of the coating applied to polymer gears to achieve an optimal design.

关键词： coating contact stress finite element method(FEM) friction polymer gear

PUB22 and PUB23 U-box E3 ubiquitin ligases negatively regulate 26S proteasome activity under proteotoxic stress conditions

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Plant Biology 2022年第3期64卷 625-631页

作者： min Yong Ahn Dong Hye seo Woo Taek Kim Department of Systems Biology Division of Life ScienceYonsei UniversitySeoul 03722Korea Institute of Life Science and Biotechnology Yonsei UniversitySeoul 03722Korea

The mechanism regulating proteasomal activity under proteotoxic stress conditions remains ***,we showed that arsenite-induced proteotoxic stress resulted in upregulation of Arabidopsis homologous PUB22 and PUB23 U-boxE3 ubiquitin ligases and that pub22 pub23 double mutants displayed arsenite-insensitive seed germination and root growth ***22/PUB23 downregulated 26 S proteasome activity by promoting the dissociation of the 19 S regulatory particle from the holo-proteasome complex,resulting in intracellular accumulation of UbG76 VGFP,an artificial substrate of the proteasome complex,and insoluble poly-ubiquitinated *** results suggest that PUB22/PUB23 play a critical role in arsenite-induced proteotoxic stress response via negative regulation of 26 S proteasome integrity.

关键词： Arabidopsis thaliana proteotoxic stress sodium arsenite U-box E3 ligases PUB22/23 26S proteasome complex

Enhancement parameters of contrast-enhanced computed tomography for pancreatic ductal adenocarcinoma: Correlation with pathologic grading

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2020年第28期26卷 4151-4158页

作者： Woorim seo Young Chul Kim seon Jeong min Sang min Lee Department of Radiology Hallym University Dongtan Sacred Heart HospitalGyeonggi-do 18450South Korea Department of Radiology Hallym University Sacred Heart HospitalGyeonggido 14068South Korea

BACKGROUND Pancreatic ductal adenocarcinoma(PDA)is a malignancy with a high mortality rate and short survival *** conventional computed tomography(CT)has been worldwide used as a modality for diagnosis of PDA,as CT enhancement pattern has been thought to be related to tumor angiogenesis and pathologic grade of *** To evaluate the relationship between the pathologic grade of pancreatic ductal adenocarcinoma and the enhancement parameters of contrast-enhanced *** In this retrospective study,42 patients(Age,mean±SD:62.43±11.42 years)with PDA who underwent surgery after preoperative CT were *** radiologists evaluated the CT images and calculated the value of attenuation at the aorta in the arterial phase and the pancreatic phase(VAarterial and VApancreatic)and of the tumor(VTarterial and VTpancreatic)by finding out four regions of *** between the tumor and the aorta enhancement on the arterial phase and the pancreatic phase(TARarterial and TARpancreatic)was figured out through dividing VT arterial by VAarterial and VTpancreatic by ***-to-aortic enhancement fraction(TAF)was expressed as the ratio of the difference between attenuation of the tumor on arterial and parenchymal images to that between attenuation of the aorta on arterial and pancreatic *** Kruskal-Wallis analysis of variance and Mann-Whitney U test for statistical analysis were *** Forty-two PDAs(23 men and 19 women)were divided into three groups:Welldifferentiated(n=13),moderately differentiated(n=21),and poorly differentiated(n=8).TAF differed significantly between the three groups(P=0.034)but TARarterial(P=0.164)and TARpancreatic(P=0.339)did *** median value of TAF for poorly differentiated PDAs(0.1011;95%CI:0.01100-0.1796)was significantly higher than that for well-differentiated PDAs(0.1941;95%CI:0.1463-0.3194).CONCLUSION Calculation of TAF might be useful in predicting the pathologic grade of PDA.

关键词： Computed tomography Pancreatic ductal carcinoma Diagnostic imaging Clinical pathology Neoplasm grading Prognosis

Data Traffic Reduction with Compressed Sensing in an AIoT System

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2022年第1期70卷 1769-1780页

作者： Hye-min Kwon Seng-Phil Hong mingoo Kang Jeongwook seo Hanshin University Osan-si18101Korea Hancom with Inc. Seongnam-si13493Korea

To provide Artificial Intelligence(AI)services such as object detection,Internet of Things(IoT)sensor devices should be able to send a large amount of data such as images and ***,this inevitably causes IoT networks to be severely *** this paper,therefore,we propose a novel oneM2M-compliant Artificial Intelligence of Things(AIoT)system for reducing overall data traffic and offering object *** consists of some IoT sensor devices with random sampling functions controlled by a compressed sensing(CS)rate,an IoT edge gateway with CS recovery and domain transform functions related to compressed sensing,and a YOLOv5 deep learning function for object detection,and an IoT *** analyzing the effects of compressed sensing on data traffic reduction in terms of data rate per IoT sensor device,we showed that the proposed AIoT system can reduce the overall data traffic by changing compressed sensing rates of random sampling functions in IoT sensor *** addition,we analyzed the effects of the compressed sensing on YOLOv5 object detection in terms of performance metrics such as recall,precision,mAP50,and mAP,and found that recall slightly decreases but precision remains almost constant even though the compressed sensing rate decreases and that mAP50 and mAP are gradually degraded according to the decreased compressed sensing ***,if proper compressed sensing rates are chosen,the proposed AIoT system will reduce the overall data traffic without significant performance degradation of YOLOv5.

关键词： 5G Internet of Things data traffic compressed sensing YOLOv5

Delayed inflammatory response evoked in nasal alloplastic implants after COVID-19 vaccination: A case report

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2022年第23期10卷 8298-8303页

作者： min-Gi seo Eun Kyung Choi Kyu Jin Chung Department of Plastic and Reconstructive Surgery College of MedicineYeungnam UniversityDaegu 42415South Korea Department of Anesthesiology and Pain Medicine College of MedicineYeungnam UniversityDaegu 42415South Korea

BACKGROUND Delayed inflammatory reactions(DIRs)in alloplast rhinoplasty are a rare complication that may occur several months to years after *** exact causes and mechanisms are unclear,but several triggering factors,including infections,trauma,dental procedures,and vaccination,have been *** SUMMARY A 39-year-old male patient who had undergone augmentation rhinoplasty 8 years ago had DIRs after the administration of the first dose of the mRNA Pfizer coronavirus disease 2019(COVID-19)*** suddenly had tender,erythematous swelling on his face 6 d after *** there was no improvement in the patient’s condition after the conservative treatment,surgical removal of an alloplastic nasal implant was *** after the surgery,the DIRs and accompanying symptoms ameliorated rapidly.A histological study conducted during surgery was fibrosis and small fragments of the hyaline *** The correlation between DIRs and COVID-19 vaccination has not been reported yet and the exact mechanism is *** the uncontrolled inflammatory reactions on the nose leave serious sequelae,surgeons should be conscious of the correlation between COVID-19 vaccines and DIRs associated with nasal alloplastic *** further histological or microbiological studies should be performed to determine the cause of DIRs.

关键词： Delayed inflammatory reactions Alloplast rhinoplasty Silicone COVID-19 Vaccination Case report