检索结果-南通市图书馆

Neural Regeneration Research 2014年第3期9卷 280-284页

作者： Dong-hoon Lee Ji-Won park Cheol-Pyo Hong Center for Medical Metrology Division of Convergence Technology Korea Research Institute of Standards and Science (KRISS) Department of Radiological Science College of Health Science Yonsei University Department of Physical Therapy College of Medical Science Catholic University of Daegu

To attain the volumetric information of the optic radiation in normal human brains, we per- formed diffusion tensor imaging examination in 13 healthy volunteers. Simultaneously, we used a brain normalization method to reduce individual brain variation and increase the accuracy of volumetric information analysis. In addition, tractography-based group mapping method was also used to investigate the probability and distribution of the optic radiation pathways. Our results showed that the measured optic radiation fiber tract volume was a range of about 0.16% and that the fractional anisotropy value was about 0.53. Moreover, the optic radiation probability fiber pathway that was determined with diffusion tensor tractography-based group mapping was able to detect the location relatively accurately. We believe that our methods and results are help- ful in the study of optic radiation fiber tract information.

关键词： nerve regeneration optic radiation diffusion tensor imaging diffusion tensor tractogra-phy magnetic resonance imaging volumetric analysis probability map group mapping visualiza-tion individual variation neural regeneration

Environmental friendly synthesis of hierarchical mesoporous platinum nanoparticles templated by fucoidan biopolymer for enhanced hydrogen evolution reaction

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2020年第11期42卷 185-190页

作者： Seung Man Lim Kyunglee Kang Hongje Jang jung Tae park Department of Chemical Engineering Konkuk University120 Neungdong-roGwangjin-guSeoul 05029Republic of Korea Department of Chemistry Kwangwoon University20 Cwangwoon-roNowon-guSeoul 01897Republic of Korea

Researching novel hydrogen evolution reaction(HER)catalysts with enhanced electrocatalytic activity,excellent stability,and cost-efficiency is of great significance for the large-scale hydrogen production from industrial electrolysis *** report the preparation of hierarchical mesoporous-Pt nanoparticles(HM-Pt NPs)with coral-like rough surface morphologies using environmental friendly and biocompatible fucoidan(Fu)biopolymer as a surface engineering compound and its application to electrocatalysts for *** designed HM-Pt NPs yields better mass activity of electrocatalysts compared to a commercial Pt/***-Pt NPs showed an overpotential of 33 mV at 10 mA cm-2 for the HER in 0.5 MH2SO4,which was highly comparable to that of the commercial Pt/C catalysts(29 mV).However,the amount of HM-Pt NPs loaded in glassy carbon electrode(0.033 mg mL-1)was approximately 20 times lower than that of the commercial Pt/C(0.64 mg *** HM-Pt NPs also maintained high catalytic stability with a consistent HER current density after 1000 continuous *** excellent HER performance is attributed to the improved electrochemical surface area,highly porous structure,and good surface wettability of the HM-Pt NPs,which results in enhanced electrocatalytic activity,decreased resistance at the electrode/electrolyte interface,and facile penetration of the electrolytes inside the electrode.

关键词： Mesoporous Fucoidan Biopolymer Low Pt content Hydrogen evolution reaction

Ultra-low concentration of total organic carbon in ultrapure water using ion-exchange resin embedding silanized magnetic nanoparticles

在线全文

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2020年第6期32卷 11-17页

作者： jung Joon Lee Jihyeon park Bo-Hyun Kim Sunjong Lee Department of Advanced Materials Science and Engineering Sungkyunkwan UniversitySuwon 16419South Korea Korea Institute of Industrial Technology 89 Yangdaegiro-gilIpjang-myeonCheonan-si 31056South Korea

Regeneration of pure water is an important issue not only for the healthy life but also for the fine control of precise processes in various *** important issue in ultrahigh purified water is to reduce the amount of total organic carbon(TOC).Herein,we introduce a new approach to reduce the TOC using the surface silanized nanoparticles,in which the magnetic nanoparticles(mNPs)are silanized and then complexed with ion exchange resin(IER)*** Fe3O4 mNPs are surface modified by using high concentrated vinyltrimethoxysilane(VTMS)and then adhered on the surface of IER *** surface modified mNPs have a thick-shell of polysiloxane layer varying from 5 to 22 nm depending on the amount of VTMS used,which leads the significant increase of specific surface *** IER beads embedding VTMS-silanized mNPs achieves about 7μg/L of the TOC level in ultrapure water system,which is two orders less than 228μg/L of the feeding water and one order less than 96μg/L from the system using pristine IER *** result is mainly attributed to the polysiloxane layer forming broccoli-like surface structure and some part by the vinyl group of VTMS exposed to the amines in the water.

关键词： Total organic carbon Ultrapure water Magnetic nanoparticle Ion-exchange resin Hybrid structure

Impregnation approach for poly(vinylidene fluoride)/tin oxide nanotube composites with high tribological performance

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2020年第2期37卷 19-25页

作者： Min Su park Jin Kyu Kim Tong-Seok Han jung Tae park Jong Hak Kim Department of Chemical and Biomolecular Engineering Yonsei University50 Yonsei-roSeodaemun-guSeoul03722Korea Department of Civil and Environmental Engineering Yonsei University50 Yonsei-roSeodaemun-guSeoul03722Korea Department of Chemical Engineering Konkuk University120 Neungdong-roGwangjin-guSeoul05029Korea

We report a composite material with the high tribological performance,which consists of onedimensional SnO2 nanotubes(ST)and a high molecular weight poly(vinylidene fluoride)(PVDF)matrix in terms of *** of PVDF in N,N-dimethylformamide(DMF)resulted in a facile penetration of PVDF into the inner hollow voids of ST,leading to the close *** between PVDF and ST results in a beneficial effect on the chain arrangement of PVDF,providing anα-phase with better tribological *** ST incorporation,the friction coefficient decreased by 85.0%to 0.408,and the specific wear rate decreased by 69.1%to 0.412,demonstrating the pivotal role of ST as a self-lubricating material due to a large interactive area and PVDF chain rearrangement.

关键词： SnO2 nanotube Composite Friction coefficient Wear rate

Verification of Beam Models for Ionic Polymer-Metal Composite Actuator

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2009年第3期6卷 232-238页

作者： hoon Cheol park Quoc Viet Nguyen Jang Woo Lee Young Tai Yoo Artificial Muscle Research Center Konkuk University Department of Advanced Technology Fusion Konkuk University Department of Materials Chemistry and Engineering Konkuk University

Ionic Polymer-Metal Composite (IPMC) can work as an actuator by applying a few voltages.A thick IPMC actuator,where Nafion-117 membrane was synthesized with polypyrrole/alumina composite filler,was analyzed to verify the equivalent beam and equivalent bimorph beam *** blocking force and tip displacement of the IPMC actuator were measured with a DC power supply and Young's modulus of the IPMC strip was measured by bending and tensile tests *** calculated maximum tip displacement and the Young's modulus by the equivalent beam model were almost identical to the corresponding measured *** element analysis with thermal analogy technique was utilized in the equivalent bimorph beam model to numerically reproduce the force-displacement relationship of the IPMC *** results by the equivalent bimorph beam model agreed well with the force-displacement relationship acquired by the measured *** is confirmed that the equivalent beam and equivalent bimorph beam models are practically and effectively suitable for predicting the tip displacement,blocking force and Young's modulus of IPMC actuators with different thickness and different composite of ionic polymer membrane.

关键词： jonic polymer-metal composite beam model displacement force

Application of signal processing techniques to the detection of tip vortex cavitation noise in marine propeller

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2013年第3期25卷 440-449页

作者： LEE Jeung-hoon HAN Jae-Moon park Hyung-Gil SEO Jong-Soo Samsung Ship Model Basin (SSMB) Marine Research Institute Samsung Heavy Industries Science TownDaejeon 305-380 Korea

The tip vortex cavitation and its relevant noise has been the subject of extensive researches up to now. In most cases of experimental approaches, the accurate and objective decision of cavitation inception is primary, which is the main topic of this paper. Although the conventional power spectrum is normally adopted as a signal processing tool for the analysis of cavitation noise, a faithful exploration cannot be made especially for the cavitation inception. Alternatively, the periodic occurrence of bursting noise induced from tip vortex cavitation gives a diagnostic proof that the repeating frequency of the bursting contents can be exploited as an indication of the inception. This study, hence, employed the Short-Time Fourier Transform （STFT） analysis and the Detection of Envelope Modulation On Noise （DEMON） specmma analysis, both which are appropriate for finding such a repeating frequency. Through the acoustical measurement in a water tunnel, the two signal processing techniques show a satisfactory result in detecting the inception of tip vortex cavitation.

关键词： tip vortex cavitation inception Short-Time Fourier Transform (STFT) Detection of Envelope Modulation On Noise(DEMON)

The influence of thermohaline fronts on chlorophyll a concentrations during spring and summer in the southeastern Yellow Sea

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2013年第9期32卷 82-90页

作者： JANG Pung-Guk LEE Tong Sup KANG jung-hoon SHIN Kyoungsoon Korea Institute of Ocean Science and Technology/South Sea Institute Department of Oceanography College of Natural SciencesPusan National University

A spatial and temporal variation in physiochemical parameters in the southeastern Yellow Sea （YS） is in- vestigated in the spring and summer of 2009 to 2011. Nutrient show a strong negative relationship with chlorophyll a （Chl a） concentration in spring, and the subsurface chlorophyll a maxima （SCM） layer was associated with the nitracline in summer. In summer, the SCM was usually found within or above the pyc- nocline and at the depths of shoals from the open sea to the coastal sea due to tidal and/or topographical fronts in the southernmost study area. High Chl a concentrations were found in the central southern YS, where the YS cold water layer expanded under the pycnocline and encountered water masses during spring and summer. After a typhoon in the summer of2011, Chl a concentration increased, especially in the central southern YS, where cold waters occurred below the pycnocline. The results suggest that the development of thermohaline fronts may play an important role in the growth and accumulation of phytoplankton biomass in the upper layer of the southeastern YS during spring and summer.

关键词： Yellow Sea Cold Water nutrient chorophyll a thermohaline front

Improvements of model-test method for cavitation-induced pressure fluctuation in marine propeller

在线全文

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2013年第4期25卷 599-605页

作者： LEE Jeung-hoon HAN Jae-Moon park Hyung-Gil SEO Jong-Soo Samsung Ship Model Basin (SSMB) Marine Research Institute Samsung Heavy Industries Science Town

Although the prediction of propeller cavitation-induced pressure fluctuation strongly depends on the model-scalemeasure- ment in a cavitation tunnel, there is still a lack of correlation with full-scale data. This paper deals with the enhancement of such a correlation deficiency by improving the conventional model-test technique, two majors of which are in the following. One is to take into account the boundary layer effect of wooden fairing plate at the ceiling of water cavitation tunnel. The other is to avoid the reso- nance frequency range of model-ship via adjusting the revolution speed of model propeller. Through a case study, for which both model and full-scale test data are available, the improved method in this study shows its validness, and furthermore a close correla- tion with full scale measurement.

关键词： cavitation boundary layer resonance

Diel vertical migration of the copepod Calanus sinicus before and during formation of the Yellow Sea Cold Bottom Water in the Yellow Sea

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2013年第9期32卷 99-106页

作者： KANG jung-hoon SEO MinHo KWON Oh Youn KIM Woong-Seo South Sea Environment Research Division Korea Institute of Ocean Science&Technology (KIOST) Deep-sea and Seabed Resources Research Division

To understand the effects of the Yellow Sea Cold Bottom Water （YSCBW） on the diel vertical migration （D- VM） of the copepod Calanus sinicus, we surveyed vertical distribution of C. sinicus at a fixed station in the Yellow Sea before （spring） and during （summer） formation of the YSCBW. Cold water （〈10℃） was observed in the bottom layer when the water column was thermally stratified in summer, but the water column was thermally well-mixed in spring 2010. Samples were collected from five different layers at 3-h intervals using an opening-closing net. Adult females （1-155 ind./m3） showed a clear normal DVM pattern throughout the entire water column in spring, whereas adult males did not migrate. DVM of copepodite V （CV） individuals was not clear, but the maximum abundance of CI-CIV occurred consistently in the upper 10-20 m layer, where there was a high concentration of chlorophyll-a （Chl-a）（0.49-1.19μg/L）. In summer, weak DVM was limited to cold waters beneath the thermocline for adult females （〈30 ind./m3）, but not for adult males. The maximum abundance of CI-CIV also occurred consistently in the subsurface layer （20-40 m） together with high concentrations of Chl-a （0.81-2.36 μg/L）. CV individuals （1-272 ind./m3） moved slightly upward noc- turnally to the near-surface layer （10-20 m）, where the average temperature was 25.74℃, but they were not found in the surface layer （0-10 m; 28.31℃）. These results indicate that the existence of the YSBCW affected food availability at depth and the vertical temperature distribution, leading to variation in the amplitude and shape of stage-specific vertical distributions （CI to adults） in C. sinicus before and during the formation of cold waters in the Yellow Sea during the study period.

关键词： Yellow Sea Cold Bottom Water (YSCBW) copepod Calanus sinicus developmental stages,diel vertical migration (DVM)

Endovascular treatment of a ruptured pseudoaneurysm of the internal carotid artery in a patient with nasopharyngeal cancer:A case report

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2022年第25期10卷 9121-9126页

作者： jung-Soo park Hyoung Gyu Jang Department of Neurosurgery Jeonbuk National University Medical School and HospitalJeonju 54907South Korea

BACKGROUND Radiation therapy(RT)for nasopharyngeal cancer can cause several *** rare cases,an internal carotid artery pseudoaneurysm can occur,which can be *** report the experience of a nasopharyngeal cancer patient who underwent radiation therapy and subsequently developed a fatal pseudoaneurysm of the petrous internal carotid *** SUMMARY A 39-year-old man was diagnosed with nasopharyngeal cancer 2 years ago(American Joint Committee on Cancer Stage T3N2M0)and received concurrent chemoradiation *** subsequently relapsed and received *** week after the 4th cycle of chemotherapy,he was admitted to the emergency room of our hospital because of massive epistaxis accompanied by a headache.A pseudoaneurysm of the petrous internal carotid artery was confirmed by digital subtraction angiography(DSA).Stent-assisted endovascular coil embolization was performed and complete occlusion was *** pseudoaneurysm was observed on DSA after coil embolization;however,intermittent epistaxis was maintained even after coil *** seven days,a diagnostic laryngoscopy was *** bleeding occurred after aspiration of the blood clot during the laryngoscopy and the patient died of hypovolemic *** this case,epistaxis may have been a sign of pseudoaneurysm;therefore,treatment such as embolization should be performed promptly,and careful management should be undertaken after *** This case highlights a rare,serious complication of RT in nasopharyngeal cancer and how it should be recognized and treated.

关键词： Pseudoaneurysm Nasopharyngeal cancer Radiation therapy Epistaxis Carotid artery pseudoaneurysm Case report