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Fourier transform infrared spectral features of plant biomass components during cotton organ development and their biological implications

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Journal of Cotton Research 2022年第2期5卷 130-142页

作者： HE Zhongqi LIU Yongliang kim hee jin TEWOLDE Haile ZHANG Hailin Southern Regional Research Center USDA-ARSNew OrleansLA 70124USA Crop Science Research Laboratory USDA-ARSMississippi StateMS 39762USA Department of Plant and Soil Sciences Oklahoma State UniversityStillwaterOK 74078USA.

Background:The majority of attenuated total reflection Fourier transform infrared(ATR FT-IR)investigations of cotton are focused on the fiber tissue for biological mechanisms and understanding of fiber development and maturity,but rarely on other cotton biomass comp on *** work examined in detail the ATR FT-IR spectral features of various cott on tissues/organs at reproductive and maturation stages,an a lyzed and discussed their biological ***:The ATR FT-IR spectra of these tissues/organs were an a lyzed and compared with the focus on the lower wavenumber fingerprinting *** outstanding FT-IR bands at 1730,1620,1525,1235,1050 and 895 cm^(-1) represented the major C=O stretching,protein Amide I,Amide II,the O-H/N-H deformation,the total C-O-C stretching and the β-glycosidic linkage in celluloses,respectively,and impacted differently between these organs with the two growth ***,the band intensity at 1620,1525,1235,and 1050 cm^(-1) were exclusively and significantly correlated to the levels of protein(Amide I bond),protein(Amide II bond),cellulose,and hemicellulose,respectively,whereas the band at 1730 cm^(-1) was negatively correlated with ash ***:The resulting observations indicated the capability of ATR FT-IR spectroscopy for monitoring changes,transportation,and accumulation of the major chemical components in these tissues over the cotton growth *** other words,this spectral technology could be an effective tool for physiological,biochemical,and morphological research related to cotton biology and development.

关键词： Cotton Fourier transform infrared spectroscopy Fiber Cellulose Protein Plant tissue

熔化极气体保护焊导电嘴载流磨损及使用寿命的研究进展

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材料导报 2020年第19期34卷 19128-19133,19151页

作者：栗卓新丛兴李红 kim hee jin 北京工业大学材料科学与工程学院北京100020 韩国工业技术研究院熔焊研究组天安330-825

现代制造业要求焊接技术向智能化、连续化、绿色化发展,目前熔化极气体保护焊焊接过程中焊丝对导电嘴的磨损率过大,频繁地停工更换和清理零部件限制了熔化极气体保护焊自动化焊接的发展。电接触条件下的载流磨损是导致材料磨损率过大的... 详细信息

现代制造业要求焊接技术向智能化、连续化、绿色化发展,目前熔化极气体保护焊焊接过程中焊丝对导电嘴的磨损率过大,频繁地停工更换和清理零部件限制了熔化极气体保护焊自动化焊接的发展。电接触条件下的载流磨损是导致材料磨损率过大的重要原因,主要体现在两个方面:(1)电接触产生焦耳热,使环境温度大幅提高,局部温度甚至超过500℃,造成电接触材料发生软化;(2)电接触点的不断运动和变化导致产生微观电弧,造成局部材料的剧烈熔融和氧化。因电接触造成的电气磨损与机械磨损相互加剧,大幅缩短了导电嘴器件的使用寿命。接触电阻是产生焦耳热和微观电弧的关键因素,镀铜钢焊丝与导电嘴之间的接触电阻值约为1.6 mΩ,而对于无镀铜钢焊,该值提高到约2.5 mΩ。导电嘴使用寿命随接触电阻、焊接电流、送丝速度增大而缩短;法向接触载荷一方面增大机械磨损,另一方面减少电气磨损,因此对导电嘴寿命有着复杂影响。高强度、高导电性导电嘴材料有利于延长导电嘴使用寿命,利用双相析出沉淀强化的Cu-Cr-Zr系铜合金能在显著提高材料强度的同时尽可能地减少因合金固溶导致的电导率损失,与此同时,石墨基、粉末冶金及复合材料导电嘴也有一定的实用性和研究价值。光洁平整的焊丝表面有利于延长导电嘴使用寿命,在无镀铜焊丝表面制备润滑性涂层能进一步提升导电嘴磨损性能。由于焊接条件的特殊性,表面涂层需兼具高温稳定性、高导电性等特征,具有表面效应和小尺寸效应的固体润滑剂在这方面具有极大的优势和应用前景。本文综述了熔化极气体保护焊导电嘴载流磨损机理的研究进展,从工艺参数、导电嘴材料、焊丝表面状态等方面分析了影响导电嘴载流磨损的因素和延长导电嘴寿命的可行方法,对减少导电嘴磨损,延长其寿命,推动机器人自动化焊接和无镀铜实心焊丝研发制造具有一定的指导意义。

关键词：熔化极气体保护焊工艺性能导电嘴寿命载流磨损

工艺与微量元素对镍基合金焊接热影响区液化裂纹影响的研究进展

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机械工程学报 2016年第6期52卷 37-45页

作者：栗卓新王恒李杨 kim hee jin TILLMANN Wolfgang 北京工业大学材料科学与工程学院北京100124 菲拉克焊接江苏有限公司常州213200 韩国工业技术研究院高级熔焊研究组多特蒙德工业大学材料工程研究所德国多特蒙德44227

镍基合金因其优异的耐高温和耐腐蚀性,广泛地应用在航空航天、核电及海洋采油等行业。基于镍基合金的重要性,研究其焊接热影响区(Heat-affected zone,HAZ)液化裂纹问题对于促进该问题的解决具有重要意义。焊接工艺的好坏直接影响到镍基... 详细信息

镍基合金因其优异的耐高温和耐腐蚀性,广泛地应用在航空航天、核电及海洋采油等行业。基于镍基合金的重要性,研究其焊接热影响区(Heat-affected zone,HAZ)液化裂纹问题对于促进该问题的解决具有重要意义。焊接工艺的好坏直接影响到镍基合金焊接性能,是导致其HAZ液化裂纹的重要因素之一。采用热处理工艺,可以获得预期的组织和性能,以降低液化裂纹敏感性。同时,合金母材中微量元素影响晶界非平衡偏析行为,会导致HAZ液化裂纹的产生。从焊接工艺、热处理工艺及微量元素三个方面综述镍基合金焊接HAZ液化裂纹的最新进展,并对液化裂纹的测试方法进行总结,对未来的研究趋势进行展望。

关键词：镍基合金热影响区液化裂纹焊接热处理微量元素

Postmortem ^(7)Li NMR analysis for assessing the reversibility of lithium metal electrodes in lithium metal batteries

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Journal of Energy Chemistry 2024年第7期94卷 430-440页

作者： Jaewon Baek Sunha kim hee-Tak kim Oc hee Han Department of Chemical&Biomolecular Engineering KAISTDaejeon 34141Republic of Korea Metropolitan Seoul Center Korea Basic Science InstituteSeoul 03759Republic of Korea Graduate School of Analytical Science&Technology Chungnam National UniversityDaejeon 34134Republic of Korea

Despite the proficiency of lithium(Li)-7 NMR spectroscopy in delineating the physical and chemical states of Li metal electrodes,challenges in specimen preparation and interpretation impede its *** this study,we conducted a comprehensive postmortem analysis utilizing ^(7)Li NMR,employing a stan-dard magic angle spinning probe to examine protective-layer coated Li metal electrodes and LiAg alloy electrodes against bare Li metal electrodes within Li metal batteries(LMBs).Our investigation explores the effects of sample burrs,alignment with the magnetic field,the existence of liquid electrolytes,and precycling on the ^(7)Li NMR *** contrasting NMR spectra before and after cycling,we identi-fied alterations in Li^(0) and Li^(+) signals attributable to the degradation of the Li metal *** NMR analyses decisively demonstrate the efficacy of the protective layer in mitigating dendrite and solid elec-trolyte interphase ***,we noted that Li*ions near the Li metal surface exhibit magnetic susceptibility anisotropy,revealing a novel approach to studying diamagnetic species on Li metal elec-trodes in *** study provides valuable insights and practical guidelines for characterizing distinct lithium states within LMBs.

关键词： NMR spectroscopy Lithium-7 Lithium metal battery Electrolyte Electrode-protective layer Solid electrolyte interface Magnetic susceptibility anisotropy Lithium-metal NMR signal Diamagnetic^(7)Li NMR signal

Feasibility assessment of phenotyping cotton fiber maturity using infrared spectroscopy and algorithms for genotyping analyses

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Journal of Cotton Research 2019年第1期2卷 44-55页

作者： kim hee jin LIU Yongliang FANG David D. DELHOM Christopher D. USDA-ARS Southern Regional Research Center Cotton Fiber Bioscience Research Unit 1100 Robert E.Lee BlvdNew Orleans LA 70124 USA USDA-ARS Southern Regional Research CenterCotton Structure and Quality Research Unit1100 Robert E. Lee BlvdNew OrleansLA 70124USA

Background:Cotton fiber maturity is an important property that partially determines the processing and performance of *** to difficulties of obtaining fiber maturity values accurately from every plant of a genetic population,cotton geneticists often use micronaire(MIC) and/or lint percentage for classifying immature phenotypes from mature fiber phenotyp es although they are complex fiber *** recent development of an algorithm for determining cotton fiber maturity(MIR)from Fourier transform infrared(FT-IR)spectra explores a novel way to measure fiber maturity efficiently and ***,the algorithm has not been tested with a genetic population consisting of a large number of progeny pla,***:The merits and limits of the MIC-or lint percentage-bas ed phenotyping method were demonstrated by comparing the observed phenotypes with the predicted phenotypes based on their DNA marker genotypes in a genetic population consisting of 708 F2 plants with various fiber *** observed MIC-based fiber phenotypes matched to the predicted phenotypes better than the observed lint percenta ge-based fiber *** lint percentage was obtained from each of F2 plants,whereas the MIC values were unable to be obtained from the entire population since certain F2 plants produced insufficient fiber mass for their *** test the feasibiility of cotton fiber infrared maturity(MIR)as a viable phenotyping tool for genetic analyses,we me asured FT-IR spectra from the second population composed of 80 F2 plants with various fiber maturities,determined MIR values using the algorithms,and compared them with their genotypes in addition to other fiber *** results showed that MIR values were successfully obtained from each of the F2 plants,and the observed MIR-based phenotypes fit well to the predicted phenotypes based on their DNA marker genotypes as well as the observed phenotypes based on a combination of MIC and lint ***

关键词： Attenuated total reflection Fourier transform infrared spectroscopy Cotton fiber maturity Crystallinity Immature fiber (im) mutant

不锈钢焊缝铁素体含量测试方法与精度的现状及进展

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机械工程学报 2014年第23期50卷 89-96页

作者：栗卓新焦俊 kim hee jin 北京工业大学材料科学与工程学院北京100124 韩国工业技术研究院高级熔焊研究组韩国天安330-825

铁素体含量对不锈钢焊缝的耐蚀、韧性、强度等性能有重要影响,准确测量或预测十分重要.铁素体含量的测试与预测方法有很多种,最常使用的是图谱法和磁测法,介绍这两种方法的最新进展.在不同实验室制备及测量试样、试样表面是否进行处理... 详细信息

铁素体含量对不锈钢焊缝的耐蚀、韧性、强度等性能有重要影响,准确测量或预测十分重要.铁素体含量的测试与预测方法有很多种,最常使用的是图谱法和磁测法,介绍这两种方法的最新进展.在不同实验室制备及测量试样、试样表面是否进行处理等都会影响测试与预测结果的精度.铁素体数（Ferrite number,FN）小于5时,不同实验室之间图谱法预测结果的波动是平均值的±60％,铁素体数在15～35时,图谱法预测结果的波动是平均值的±30％.磁测法测量的波动是平均值的±20％,小于图谱预测法,是目前较精确的测试方法.新的预测方法考虑了元素之间相互作用和冷却速度等因素对铁素体含量的影响,提高了预测的精度.针对铁素体数测试结果不可避免的波动问题,提出目标范围这一概念来解决焊材设计者与使用者对测试结果产生的分歧.

关键词：不锈钢焊缝铁素体含量铁素体数波动

TonEBP expression is essential in the IL-1β–induced migration and invasion of human A549 lung cancer cells

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Oncology Research 2024年第1期32卷 151-161页

作者： hee JU SONG TAEhee kim HAN NA CHOI SOO jin kim SANG DO LEE Department of Physiology School of MedicineChungnam National UniversityDaejeon35015Korea

Lung cancer has the highest mortality rate among all cancers,in part because it readily *** tumor microenvironment,comprising blood vessels,fibroblasts,immune cells,and macrophages[including tumor-associated macrophages(TAMs)],is closely related to cancer cell growth,migration,and *** secrete several cytokines,including interleukin(IL)-1β,which participate in cancer migration and invasion.p21-activated kinase 1(PAK1),an important signaling molecule,induces cell migration and invasion in several ***responsive enhancer-binding protein(TonEBP)is also known to participate in cancer cell growth,migration,and ***,the mechanisms by which it increases lung cancer migration remain ***,in this study,we aimed to elucidate the mechanisms by which IL-1βand TonEBP affect lung cancer cell migration and *** found that A549 cocultured-MΦ-secreted IL-1βinduced A549 cell migration and invasion via the PAK1 *** deficiency reduced A549 cell migration and invasion and increased responsiveness to IL-1β–induced migration and ***1 phosphorylation,which was promoted by IL-1β,was reduced when TonEBP was *** results suggest that TonEBP plays an important role in IL-1βinduction and invasiveness of A549 cells via the PAK1 *** findings could be valuable in identifying potential targets for lung cancer treatment.

关键词： Lung cancer TonEBP Tumor microenvironment Tumor-associated macrophage IL-1β

Random pinhole attenuator for high-power laser beams

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High Power Laser Science and Engineering 2024年第3期12卷 116-121页

作者： Seong Cheol Park Hyeok Yun jin Woo Yoon Seong Ku Lee Jae hee Sung Il Woo Choi Chang hee Nam Kyung Taec kim Department of Physics and Photon Science Gwangju Institute of Science and TechnologyGwangjuRepublic of Korea Center for Relativistic Laser Science Institute for Basic ScienceGwangjuRepublic of Korea Advanced Photonics Research Institute Gwangju Institute of Science and TechnologyGwangjuRepublic of Korea

The intensity attenuation of a high-power laser is a frequent task in the measurements of optical *** intensity can be attenuated by inserting an optical element,such as a partial reflector,polarizer or absorption *** devices are,however,not always easily applicable,especially in the case of ultra-high-power lasers,because they can alter the characteristics of a laser beam or become easily *** this study,we demonstrated that the intensity of a laser beam could be effectively attenuated using a random pinhole attenuator(RPA),a device with randomly distributed pinholes,without changing the beam *** this device,a multi-PW laser beam was successfully attenuated and the focused beam profile was measured without any alterations of its *** addition,it was confirmed that the temporal profile of a laser pulse,including the spectral phase,was ***,the RPA possesses significant potential for a wide range of applications.

关键词： high-power laser intensity attenuation laser diagnostics

690 MPa级以上高强钢焊接熔敷金属微观组织及其联合贝氏体的研究进展

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中国材料进展 2019年第12期38卷 1169-1176页

作者：栗卓新苏小虎李红 kim hee jin 北京工业大学材料科学与工程学院北京100124 韩国工业技术研究院天安330825

690 MPa级以上高强钢的发展和工程应用受限于缺乏与其强韧性相匹配的焊接材料,其根本原因是以针状铁素体为主的690 MPa级以下高强钢熔敷金属的强韧化理论已经不能指导新一代高强钢焊接熔敷金属的设计。因此,解决该问题的关键是寻求最佳... 详细信息

690 MPa级以上高强钢的发展和工程应用受限于缺乏与其强韧性相匹配的焊接材料,其根本原因是以针状铁素体为主的690 MPa级以下高强钢熔敷金属的强韧化理论已经不能指导新一代高强钢焊接熔敷金属的设计。因此,解决该问题的关键是寻求最佳的熔敷金属微观组织结构。综述了690 MPa级以上高强钢焊接熔敷金属中出现的联合贝氏体和其它各类微观组织对其强韧性的影响。其中,由不同形貌贝氏体相和针状铁素体相组成的复相分割结构可使焊接熔敷金属实现良好的强韧性匹配;然而,联合贝氏体作为下贝氏体的一种,其大尺寸的特点会显著降低高强钢焊接熔敷金属的强韧性;此外,可以通过物理冶金改善高强钢焊接熔敷金属的性能。

关键词：高强钢微观组织联合贝氏体焊接熔敷金属强韧性