检索结果-南通市图书馆

Nano Research 2015年第11期8卷 3553-3561页

作者： Hui song Su-young son Seul ki kim Gun young Jung School of Materials Science and Engineering Gwangju Institute of Science and Technology (GIST) Gwangju 500-712 Republic of Korea Carbon Convergence Materials Research Center Institute of Advanced Composite Materials Korea Institute of Science and Technology (KIST) Jeollabuk-do 565-905 Republic of Korea

Hierarchical tin（Ⅲ） oxide, Sn3O4, nanospheres were synthesized via hydrothermal reaction under strongly acidic ambient conditions. The morphology of Sn3O4 varied with decreasing pH. The prickly SnaO4 nanospheres changed into SnaO4 nanospheres covered with single-crystalline nanoplates having a high BET surface area of ca. 55.05 m^2·g^-1 and a band gap of ca. 2.25 eV. Small amounts （0.05 g） of the hierarchical Sn3O4 nanostructures completely decomposed a 30% methyl orange （MO） solution in 100 mL deionized water within 15 min under one sun condition （UV ＋ visible light）. The Sn3O4 photocatalyst exhibited a fast decomposition rate of 1.73 ×10^-1 min^-1, which is a 90.86% enhancement relative to that of the commercially available P25 photocatalyst. The high photocatalytic activity of the hierarchical Sn3O4 nanostructures is attributed to its ability to absorb visible light and its high surface-to-volume ratio.

关键词： Sn3O4 hierarchical structure hydrothermal morphology engineering photocatalyst

Synapsing with NG2 cells(polydendrocytes),unappreciated barrier to axon regeneration?

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

Neural Regeneration Research 2015年第3期10卷 346-348页

作者： young-Jin son Shriners Hospitals Pediatric Research Center and Department of Anatomy and Cell Biology Temple University School of Medicine

Have you heard of NG2 cells or NG2 glia or polydendro- cytes~. These are new names for the precursor cells that used to be referred to as oligodendrocyte precursor cells （OPCs）, which become the oligodendrocytes that myelinate central nervous system （CNS） axons. Evidence suggests, however, that they have other functions, besides differentiating into oligodendrocytes. Most notably, the OPCs/NG2 cells are uni- formly distributed in grey matter as well as in white matter, which matches poorly with the distribution of myelinating oligodendrocytes. Furthermore, not every NG2 cell is fated to become an oligodendrocyte. Hence the term OPC can be fairly applied only when discussing the role of these cells in the oligodendrocyte lineage.

关键词： NG cell Synapsing with NG2 cells polydendrocytes unappreciated barrier to axon regeneration

The Immersed Interface Hybridized Difference Method for Parabolic Interface Problems

在线全文

学校读者我要写书评

暂无评论

Numerical Mathematics(Theory,Methods and Applications) 2022年第2期15卷 336-359页

作者： youngmok Jeon son-young Yi Department of Mathematics Ajou UniversitySuwon 16499Republic of Korea Department of Mathematical Sciences The University of Texas at El PasoEl PasoTX 79968USA

We propose several immersed interface hybridized difference methods(IHDMs),combined with the Crank-Nicolson time-stepping scheme,for parabolic interface *** IHDM is the same as the hybrid difference method away from the interface cells,but the finite difference operators on the interface cells are modified tomaintain the same accuracy throughout the entire *** themodification process,we consider virtual extensions of two sub-solutions in the interface cells in such a way that they satisfy certain jump equations between *** propose several different sets of jump equations and their resulting discrete methods for one-and two-dimensional *** numerical results are presented to demonstrate the accuracy and robustness of the proposed methods.

关键词： Parabolic interface problem hybrid difference method immersed interface

A simple,sensitive and non-destructive technique for characterizing bovine dental enamel erosion:attenuated total reflection Fourier transform infrared spectroscopy

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

International Journal of Oral Science 2016年第1期8卷 54-60页

作者： In-Hye kim Jun Sik son Bong ki Min young Kyoung kim Kyo-Han kim Tae-Yub Kwon Department of Dental Science Graduate SchoolKyungpook National UniversityDaeguKorea Korea Textile Development Institute DaeguKorea Center for Research Facilities Yeungnam UniversityGyeongsanKorea Department of Conservative Dentistry School of DentistryKyungpook National UniversityDaeguKorea Department of Dental Biomaterials School of DentistryKyungpook National UniversityDaeguKorea

Although many techniques are available to assess enamel erosion in vitro, a simple, non-destructive method with sufficient sensitivity for quantifying dental erosion is required. This study characterized the bovine dental enamel erosion induced by various acidic beverages in vitro using attenuated total reflection Fourier transform infrared （ATR-FTIR） spectroscopy. Deionized water （control） and 10 acidic beverages were selected to study erosion, and the pH and neutralizable acidity were measured. Bovine anterior teeth （110） were polished with up to 1 200-grit silicon carbide paper to produce flat enamel surfaces, which were then immersed in 20 mL of the beverages for 30 min at 37 ℃. The degree of erosion was evaluated using ATR-FTIR spectroscopy and Vickers＇ microhardness measurements. The spectra obtained were interpreted in two ways that focused on the ~1, ~3 phosphate contour： the ratio of the height amplitude of ~3 P04 to that of/11 P04 （Method 1） and the shift of the v3 P04 peak to a higher wavenumber （Method 2）. The percentage changes in microhardness after the erosion treatments were primarily affected by the pH of the immersion media. Regression analyses revealed highly significant correlations between the surface hardness change and the degree of erosion, as detected by ATR-FTIR spectroscopy （P〈0.001）. Method 1 was the most sensitive to these changes, followed by surface hardness change measurements and Method 2. This study suggests that ATR- FTIR spectroscopy is potentially advantageous over the microhardness test as a simple, non-destructive, sensitive technique for the quantification of enamel erosion.

关键词： acidic beverage enamel erosion Fourier transform infrared spectroscopy microhardness sensitivity

Cutoff characteristics of dielectric-filled circular holes embedded in dispersive plasmonic medium

在线全文

学校读者我要写书评

暂无评论

Chinese Optics Letters 2009年第10期7卷 904-908页

作者： ki young kim Department of Physics National Cheng Kung University

The cutoff characteristics of dielectric-filled circular holes embedded in a dispersive plasmonic medium are investigated. Since two distinctive operating modes, surface plasmon polariton and circular waveguide modes, can exist in the slow and fast wave regions, respectively, the cutoff characteristics for each are separately investigated for linear and radial polarizations of the guided fields. As a result, the cutoff wavelengths for the linear and radial polarizations with very small subwavelength hole radii are found to be limited by the plasma resonance wavelength and plasma wavelength, which in turn are dependent and independent, respectively, of the dielectric constant of the dielectric filler material.

关键词： Circular waveguides Polarization Surface plasmon resonance

Fluorescent nanoswitch for monitoring specific pluripotency-related microRNAs of induced pluripotent stem cells： Development of polyethyleneimine- oligonucleotide hybridization probes

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 2545-2559页

作者： Seungmin Han Hye young son Byunghoon Kang Eunji Jang Jisun ki Na Geum Lee Jongjin Park Moo-Kwang Shin Byeonggeol Mun Jeong-ki Min Seungjoo Haam Department of Chemical and Biomolecular Engineering College of Engineering Yonsei University Seou1120-749 Republic of Korea Department of Radiology College of Medicine Yonsei University Seou1120-752 Republic of Korea Severance Biomedical Science Institute College of Medicine Yonsei University Seou1120-752 Republic of Korea Biotherapeutics Translational Research Center Korea Research Institute of Bioscience and Biotechnology Daejeon 34141 Republic of Korea Department of Biomolecular Science University of Science & Technology Daejeon 34113 Republic of Korea

The isolation of high-grade （i.e. high-pluripotency） human induced pluripotent stem cells （hiPSCs） is a decisive factor for enhancing the purity of hiPSC populations or differentiation efficiency. A non-invasive imaging system that can monitor microRNA （miRNA） expression provides a useful tool to identify and analyze specific cell populations. However, previous studies on the monitoring/isolation of hiPSCs by miRNA expression have limited hiPSCs＇ differentiation system owing to long-term incubation with miRNA imaging probe-nanocarriers. Therefore, we focused on monitoring high-grade hiPSCs without influencing the pluripotency of hiPSCs. We reduced nanoparticle transfection time, because hiPSCs are prone to spontaneous differentiation under external factors during incubation. The fluorescent nanoswitch （＂ON＂ with target miRNA）, which can be applied for either imaging or sorting specific cells by fluorescence signals, contains an miRNA imaging probe （miP） and a PEI-PEG nanoparticle （miP-P）. Consequently, this nanoswitch can sense various endogenous target miRNAs within 30 min in vitro, and demonstrates strong potential for not only imaging but also sorting pluripotent hiPSCs without affecting pluripotency. Moreover, miP-P-treated hiPSCs differentiate well into endothelial cells, indicating that miP-P does not alter the pluripotency of hiPSCs. We envisage that this miRNA imaging system could be valuable for identifying and sorting high-grade hiPSCs for improved practical applications.

关键词： induced pluripotent stem cells (iPSCs) pluripotency microRNA (miRNA) fluorescence imaging nanoparticle

Separation of primary solid phases from Al-Si alloy melts

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

China Foundry 2014年第4期11卷 382-395页

作者： ki young kim School of Energy Materials and Chemical EngineeringKorea University of Technology and EducationChungnam 330-708Korea

The iron-rich solids formed during solidification of Al-Si alloys which are known to be detrimental to the mechanical,physical and chemical properties of the alloys should be *** the other hand,Al-Si hypereutectic alloys are used to extract the pure primary silicon which is suitable for photovoltaic cells in the solvent refining *** of the important issues in iron removal and in solvent refining is the effective separation of the crystallized solids from the Al-Si alloy *** paper describes the separation methods of the primary solids from Al-Si alloy melts such as sedimentation,draining,filtration,electromagnetic separation and centrifugal separation,focused on the iron removal and on the separation of silicon in the solvent refining process.

关键词： separation Al-Si alloys primary solids iron removal silicon extraction

Snowstorm over the Southwestern Coast of the Korean Peninsula Associated with the Development of Mesocyclone over the Yellow Sea

在线全文

学校读者我要写书评

暂无评论

Advances in Atmospheric Sciences 2008年第5期25卷 765-777页

作者： ki-young HEO Kyung-Ja HA Division of Earth Environmental System College of Natural Sciences Pusan National University Korea

This study investigates the characteristics of a heavy snowfall event over the southwestern part of the Korean Peninsula on 4 December 2005. The snowstorm was a type of mesoscale maritime cyclone which resulted from barotropic instability, and diabatic heating from the warm ocean in continental polar air masses. Based on surface observations, radiosonde soundings, MTSAT-1R satellite data and the 10-km grid RDAPS （Regional Assimilation and Prediction System based on the PSU/NCAR MM5） data, the evolution of the mesocyclone is explained by the following dynamics; （1） In the initial stage, the primary role in the cyclogenesis process of the mesocyclone is a barotropic instability in the horizontal shear zone. （2） In the developing stage, the mesocyclone moves and deepens into a baroclinic zone corresponding to the surface heating and moistening. （3） In the mature stage, it is found that the mesocyclone is intensified by the destabilization caused by enhanced low-level heating and condensation, the moisture flux convergence, and the interaction between upper and lower-level potential vorticity anomalies. We suggest that a checklist with stepwise indicators responsible for development be prepared for the forecasting of heavy snowfall over the southwestern part of the Korean Peninsula.

关键词： heavy snowfall mesocyclone baroclinic instability barotropic instability stepwise roles potential vorticity anomalies

DICE:An Effective Query Result Cache for Distributed Storage Systems

在线全文

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2010年第5期25卷 933-944页

作者： Jun-ki Min Member, A CM Mi-young Lee School of Computer Science and Engineering Korea University of Technology and Education Byeongcheon-myeon Cheonan Chungnam 330-708 Korea Cloud Computing Research Department Electronics and Telecommunications Research Institute (ETRI) Daejeon 305-700 Korea

Due to the proliferation of Internet and Intranet,the distributed storage systems have received a lot of attention. These systems span a large number of machines and store huge amount of data for a lot of *** the distributed storage systems,a row can be directly accessed using a row *** concentrate on a problem of efficient processing of queries whose predicate is on a column but not a row *** this paper,we present a cache management technique,called DICE which maintains query results of range queries to support the next range *** accelerate the search time of the cached query results,we use modified Interval Ski *** addition,we devise a novel cache replacement policy since DICE maintains an interval rather than a data *** our cache replacement policy considers the properties of intervals,our proposed technique is more efficient than traditional buffer replacement *** experimental result demonstrates the efficiency of our proposed technique.

关键词： distributed system range query query caching Interval Skip List cache replacement

Fast ethylamine gas sensing based on intermolecular charge-transfer complexation

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2012年第4期23卷 484-487页

作者： Eun Mi Lee Seon young Gwon young A son Sung Hoon kim BK21 FTIT Department of Advanced Organic Materials and Textile System EngineeringChungnam National UniversityDaejeon 305-764Republic of Korea Department of Textile System Engineering Kyungpook National UniversityDaegu 702-701 Republic of Korea School of Chemistry Science & Technology Zhanjiang Normal UniversityZhanjiang 524048China

We have investigated the fast ethylamine gas sensing of 2-chloro-3,5-dinitrobenzotrifluoride（CDBF） loaded poly（acrylonitrile） nanofiber based on an intermolecular charge-transfer *** response and recovery were ach... 详细信息

关键词： Ethylamine gas Fast gas sensing 2-Chloro-3 5-dinitrobenzotrifluoride(CDBF) Electrospinning PAN nanofiber Intermolecular charge-transfer(CT) complexation