检索结果-南通市图书馆

Relationship between decreased visual acuity and physical activity time in school age children

在线全文

学校读者我要写书评

暂无评论

Frontiers of Nursing 2021年第2期8卷 113-120页

作者： hanna Lee jeong-Won han Department of Nursing Gangneung-Wonju National UniversityGangwon-do 25457Korea College of Nursing Science Kyung Hee UniversityKyunghee-daeroDongdaemun-guSeoul 02453Korea

Objective:This study aimed to investigate the physical activity of children with decreased visual acuity,thereby providing basic data for developing strategies to enhance the physical activity of school-age ***:The participants were 1,194 children and 1,194 parents who participated in the 10th Korean Children Panel *** regression analysis was conducted to examine the status of the physical activity of children with decreased visual acuity according to the accessibility of community ***:The mother perceived the accessibility of community facilities as low,children with decreased visual acuity reported 1.20 times shorter over-the-weekend leisure activity time compared with vision-typical children,and they spent 1.41 and 1.33 times shorter on caring for pets and religious activity,***:To increase the physical activity of children with decreased visual acuity,family-oriented interventions should be *** is also important to establish a community environment with enhanced accessibility of community facilities by examining the level of accessibility perceived by parents.

关键词： activity child community physical school

Electrochemical behavior of dental implant system before and after clinical use

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2009年第4期19卷 846-851页

作者： Chae-Heon CHUNG Hee-Jung KIM Yong-Tae jeong Mee-Kyoung SON Yong-Hoon jeong han-Cheol CHOE Department of Prosthodontics College of DentistryChosun University Department of Dental Materials & Research Center of Nano-Interface Activation for Biomaterials College of DentistryChosun University

Electrochemical behavior of dental implant system before and after clinical use(in vivo and in vitro) was researched by using abutment and titanium *** simulate an oral environment,the samples of clinically used and non-used implant systems as a working electrode were exposed to artificial saliva at(36.5±1) ℃.Electrochemical tests were carried out using a *** electrochemical test,the corrosion morphology of each sample was investigated by FE-SEM and *** corrosion potential and pitting potential of clinically used implant system are lower than those of non-used implant system,and clinically used implant system exhibits a lower range of passivation,indicating a less degree of inherent resistance against chloride *** polarization resistance decreases in the case of clinically used implant system,whereas,Rp for clinically non-used implant system increases compared with clinically used implant system.

关键词：电化学行为种植制度临床应用使用制度临床使用电化学测试夹具系统腐蚀形态

Structural stability estimation of whirling unit

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2009年第B09期19卷 202-208页

作者： Son-Jae HWAN han-Chang woo Lee-Sang RYONG Lee-Young MOON Daegu Machinery Institute of Component & Materials Foundation Department of Automobile Yeungnam College of Science & Technology Department of Mechanical Engineering Kyung pook National University

Whirling is a cutting process in which a series of cutting edges on whirling ring remove material by turning over a rotating workpiece. In this study static and dynamic stability of whirling unit was estimated by using ADAMS and NASTRAN softwares. Each maximum force acting on the bearing attached to the spindle assembly and the cutting tool attached to the whirling ring with the rotating speed of 6 000 r/min was 235 N and 902 N respectively. The maximum stress of 0.74 MPa on the base frame is far smaller than the yield strength of 282 MPa. The calculated natural frequency of 148 Hz of the system is far from the frequency of the driving speed of 6 000 r/min. The experimentally obtained maximum cutting force of 792 N is smaller than that of calculated value. And the experimentally obtained natural frequency of 118 Hz is beyond the driving speed of 6000 r/min. From above results it can be judged that the whirling system is statically and dynamically stable.

关键词：旋转工件稳定性评价 NASTRAN软件动态稳定性结构单元固有频率行车速度

High-efficiency organic solar cells enabled by an alcohol-washable solid additive

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2021年第12期64卷 2161-2168页

作者： Yuanpeng Xie Hwa Sook Ryu Lili han Yunhao Cai Xiaopeng Duan Donghui Wei han Young woo Yanming Sun School of Chemistry Beihang UniversityBeijing100191China Department of Chemistry College of ScienceKU-KIST Graduate School of Converging Science and TechnologyKorea UniversitySeoul136-713Korea College of Chemistry and Molecular Engineering Zhengzhou UniversityZhengzhou450001China

The solvent additive strategy has been widely utilized to boost the power conversion efficiency(PCE)of organic solar cells(OSCs).However,the residual solvent additive in the active layer tends to induce a gradual morphology degradation and further influences the long-term stability of ***,a solid additive,1,4-diiodobenzene(DIB),was introduced to fabricate efficient *** found that the treatment of DIB can lead to optimized morphology to form a bicontinuous network with intensified intermolecular packing in the donor and acceptor ***,DIB can be easily removed from the active layer via a simple alcohol washing process and no further post-thermal annealing is needed,which is desirable for large-scale manufacturing of *** a result,high efficiencies of 17.47%for PM6:Y6 and 18.13%(certified as 17.7%)for PM6:BTP-eC9 binary OSCs are achieved,which are among the highest efficiencies reported for binary OSCs thus ***,OSCs fabricated with DIB also exhibit superior stability compared with the as-cast and traditional solvent additive processed ***,DIB was successfully applied in different active layers,manifesting its general *** work provides a feasible approach to enhance both the efficiency and stability of OSCs.

关键词： organic solar cells solid additive alcohol washing process efficiency stability

Role of dietary gamma-aminobutyric acid in broiler chickens raised under high stocking density

在线全文

学校读者我要写书评

暂无评论

Animal Nutrition 2020年第3期6卷 293-304页

作者： Su-Been jeong Yoo Bhin Kim jeong.woo Lee Da-Hye Kim Byung-Hern Moon Hong-Hee Chang Yang-Ho Choi Kyung-woo Lee Department of Animal Science and Technology Konkuk UniversitySeoul05029Republic of korea CellTech Co. Ltd.Chungbuk27622Republic of Korea Department of Animal Science Gyeongsang National Universityjinju52828Republic of Korea

The present study was conducted to evaluate the effects of dietary gamma-aminobutyric acid(GABA)in broiler chickens raised in high stocking density(HSD)on performance and physiological responses.A total of 900 male broiler chicks(Ross 308)at 1 d old were assigned in a 2×2 factorial arrangement to 4 treatments(10 replicates per treatment)with stocking density,7.5 birds/m^2(low stocking density;LSD)or 15 birds/m^2(HSD),and dietary GABA,0 or 100 mg/*** raised in HSD exhibited a decrease in body weight gain in all phases(Phank on d 21 was noted(P=0.024).Dietary GABA exhibited an opposite effect on the concentrations of cecal short-chain fatty acids depending on stocking density leading to a moderate to significant *** density decreased alpha-1-acid glycoprotein whereas dietary GABA decreased heterophil-to-lymphocyte ratio and corticosterone in blood or serum *** biochemical parameters were altered by stocking density or dietary *** is concluded that dietary GABA alleviated stress indices including corticosterone and heterophilto-lymphocyte ratio,but failed to reverse stocking density-induced growth depression.

关键词： Gamma-aminobutyric acid Stocking density Growth performance Stress indicator Broiler chicken

On-the-fly dopant redistribution in a silicon nanowire p-n junction

在线全文

学校读者我要写书评

暂无评论

Nano Research 2017年第8期10卷 2845-2855页

作者： Dong-II Moon Myeong-Lok Seol Jin-woo han M. Meyyappan Center for Nanotechnology NASA Ames Research Center Moffett Field CA 94035 USA

Dopant redistribution in a silicon nanowire （SiNW） p-n junction is found to occur owing to self-heating effects. A SiNW is doped to form back-to-back diodes and is thermally isolated by an oxide layer on its bottom side and by air on the other sides. When a high level of current flows, the inner body temperature is found to increase enough to cause dopant diffusion and even to reach the silicon melting point due to Joule heating. This experimentally observed electrothermal behavior is also validated through numerical simulation. The conductivity change is dependent on the total power density and the change becomes permanent once the device suffers self-heating beyond a threshold point. Finally, the dopant redistribution is directly visualized using scanning capacitance microscopy for the first time.

关键词： nanowire degradation Joule heating dopant redistribution scanning capacitance microscopy

Effect of Palladium Nanoparticles on Photocatalytic Characteristics of N doped Titania Catalyst

维普期刊数据库评论

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 Materials Science & Technology 2015年第6期31卷 664-669页

作者： Jong-Ho Lee jeong-Il Youn Young-Jig Kim han-Jun Oh Department of Chemistry Hanseo University School of Advanced Materials Engineering Sungkyunkwan University Department of Materials Science Hanseo University

To improve the photocatalytic efficiency of TiO2nanotubular catalyst,N doped and Pd decorated titania nanotubes was successfully synthesized via anodizing,hydrazine hydrate treatment and photoreduction of Pd *** small Pd nanoparticles were precipitated on TiO2nanotubes through photoreduction of Pd ions,and its distribution is relatively *** X-ray photoelectron spectrometry（XPS） result,the N 1s spectrum represents two peaks with binding energy at 399.7 and 400.7 eV,which suggests that the nitrogen elements doped by hydrazine hydrate treatment are located in interstitial sites of the TiO2crystalline *** N doped TiO2nanotubes with Pd particles,a high photocurrent was detected due to increase of interface charge carrier separation ***,N doped and Pd decorated TiO2nanotubes exhibited much higher dye destruction efficiency and rate constant due to the synergistic effect of the N dopant and the Pd deposition on TiO2nanotubes.

关键词： Pd nanoparticle Titania nanotube Anodizing Dye dec

Effect of Al coating conditions on laser weldability of Al coated steel sheet

在线全文

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2009年第4期19卷 946-951页

作者： Jung-han LEE Jong-Do KIM Jin-Seok OH Seo-jeong PARK Graduate School Korea Marine University Division of Marine Engineering System Korea Marine University Welding Research Center

Al coated steel sheets with excellent heat resistance,thermal reflection,and corrosion resistance are widely used in various *** laser weldability of the Al coated steel sheet for full penetration welding was *** phenomenon caused by intermixed aluminum and behavior of aluminum in the weld were *** coated steel sheets that have various thickness and coating mass were prepared for laser *** effects of parameters such as welding conditions and Al coating conditions were *** content mixed in the weld after laser welding was evaluated,and then a correlation between the mixed Al and mechanical properties was *** results show that the Al-rich zones which have Fe-Al intermetallic compounds are found in the *** intermetallic compounds cause the decreased strength of the weld.

关键词：铝合金焊接钢板焊接激光焊接 Al涂层金属间化合物涂层钢板涂层质量焊接条件

Accelerated identification of equilibrium structures of multicomponent inorganic crystals using machine learning potentials

在线全文

学校读者我要写书评

暂无评论

npj Computational Materials 2022年第1期8卷 1027-1036页

作者： Sungwoo Kang Wonseok jeong Changho Hong Seungwoo Hwang Youngchae Yoon Seungwu han Department of Materials Science and Engineering Seoul National UniversitySeoul08826Korea

The discovery of multicomponent inorganic compounds can provide direct solutions to scientific and engineering challenges,yet the vast uncharted material space dwarfs synthesis *** the crystal structure prediction(CSP)may mitigate this frustration,the exponential complexity of CSP and expensive density functional theory(DFT)calculations prohibit material exploration at ***,we introduce SPINNER,a structure-prediction framework based on random and evolutionary *** speed and accuracy of neural network potentials(NNPs),the program navigates configurational spaces 10^(2)–10^(3) times faster than DFT-based ***,SPINNER incorporates algorithms tuned for NNPs,achieving performances exceeding conventional *** blind tests on 60 ternary compositions,SPINNER identifies experimental(or theoretically more stable)phases for~80%of *** benchmarked against data-mining or DFT-based evolutionary predictions,SPINNER identifies more stable phases in many *** developing a reliable and fast structure-prediction framework,this work paves the way to large-scale,open exploration of undiscovered inorganic crystals.

关键词： materials inorganic equilibrium