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Preparation of Nitrogen-doped Carbon Dots from Coke Powder as a Fluorescent Chemosensor for Selective and Sensitive Detection of Cr (Ⅵ)

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Journal of Wuhan University of Technology(Materials Science) 2022年第6期37卷 1096-1104页

作者：孟娟 LI Shiqian 丁玲 ZHOU Chuang JIANG Rui ZHANG Qingtian CHENG Zhengzai GAUTHIER Mario hu ya 伍林 School of Chemistry and Chemical Engineering Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steel makingWuhan University of Science and TechnologyWuhan 430081China Fujian Universities and Colleges Engineering Research Center of Modern Facility Agriculture of Fujian University Fujian Polytechnic Normal UniversityFuqing 350300China Chemistry Department University of WaterlooWaterlooOntarioN2L 3G1Canada

The nitrogen-doped carbon dots(N-CDs)were prepared by using coke powder as carbon source and one-step hydrothermal method.The N-CDs were studied as a fluorescent chemosensor for determining Cr(Ⅵ)in water.The selective,sensitive,reproducibility and stability of as-prepared N-CDs were investigated.The morphology,composition and properties of N-CDs were characterized by a series of methods.The fluorescence quenching of N-CDs by Cr(Ⅵ)was explored.The experimental results reveal that the obtained N-CDs have great hydrophilicity and strong luminescence properties,which demonstrates the successful doping of nitrogen into the CDs.The surface-active groups and emission wavelength range of CDs increase due to the electronegativity and electron donor effect of doping N atom.Furthermore,the N-CDs exhibit good photochemical properties for the detection of Cr(Ⅵ),including a wide linear range from 0.3 to 200μM(R^(2)=0.9935)and a low detection limit of 0.10μM at the signal-to-noise ratio of 3(S/N=3).Moreover,the N-CDs as a sensor was used successfully for Cr(Ⅵ)detection in real water samples with recovery rates of 99.9%-110.6%.This sensor also shows highly reproducibility and stability.The N-CDs fluorescent chemical sensor may be a potential candidate for applying in the field of other fluorescent chemical sensing,catalysis,photoelectric devices and other fields.

关键词： carbon dots nitrogen doping preparation fluorescence detection Cr(Ⅵ)

Spatial Pattern of Long-term Residence in the Urban Floating Population of China and its Influencing Factors

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Chinese Geographical Science 2021年第2期31卷 342-358页

作者： CHEN Le XI Meijun JIN Wanfu hu ya School of Tourism&Research Institute of human Geography Xi’an International Studies UniversityXi’an 710128China School of Economics Xi’an University of Finance and EconomicsXi’an 710100China School of Geography and Tourism Guangdong University of Finance and EconomicsGuangzhou 510320China

Exploring long-term residence among the urban floating population is crucial to understanding urban growth in China,particularly since the 2008 financial crisis.By using China Migrants Dynamic Survey data for 2012–2014,China Labor-force Dynamics Survey data for 2014–2016,and macroscale urban matched data,we analyzed the spatial pattern of long-term residential behavior in China’s urban floating population in 2012–2016 and developed an urban spatial utility equilibrium model containing‘macro’urban factors and‘micro’individual and household factors to explain the pattern.The results first revealed that long-term residence is defined as≥6 yr for the urban floating population in China.Second,members of this population are more likely to be long-term residents of the megacities in the three urban agglomerations in eastern China as well as of small and medium-sized cities in western and northeastern China,whereas short-term residence is more likely in cities in central China and near the three urban agglomerations.Third,urban population density and housing prices,both have a significant U-shaped effect,are main factors affecting the spatial pattern of long-term residence.

关键词： long-term residence urban floating population spatial pattern spatial utility equilibrium model China

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基于脑科学视角下的钢琴教学理论探析及应用

新疆艺术学院学报 2024年第2期22卷 104-110页

作者：胡娅天津音乐学院天津300171

钢琴演奏是一项系统工程,既包括了身体四肢的物理运动,也包含了脑神经通路的传输传导。熟练演奏一首钢琴作品,从手指触键的那一刻起,到在舞台上挥洒自如地演绎,我们经历了视觉反射、听觉记忆、触觉反馈等一系列的过程,脑神经系统与肌肉... 详细信息

钢琴演奏是一项系统工程,既包括了身体四肢的物理运动,也包含了脑神经通路的传输传导。熟练演奏一首钢琴作品,从手指触键的那一刻起,到在舞台上挥洒自如地演绎,我们经历了视觉反射、听觉记忆、触觉反馈等一系列的过程,脑神经系统与肌肉运动系统深度融合,直至本能条件反射,从而实现“内化于心,外化于行”,这些无不是脑科学知识在钢琴演奏中的重要应用。本文通过剖析和运用脑科学相关理论知识,分析并解决钢琴教学中遇到的提升学生内驱力、增强作品理解力等若干问题,从而架设起联通脑科学和钢琴教学的重要桥梁。

关键词：脑科学钢琴教学神经系统理论探析

维普期刊数据库博看期刊

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石墨烯改性树脂材料的研究进展

民用飞机设计与研究 2024年第1期 86-94页

作者：胡雅上海飞机设计研究院上海201210

讨论了石墨烯作为增强相制备石墨烯/树脂材料(graphene/resin materials,简称GR)的方法,分析不同制备工艺的特点。系统阐述了石墨烯改性树脂材料在力学、耐热、导电和耐摩擦等性能上的研究现状,分析了添加石墨烯对树脂材料性能产生影响... 详细信息

讨论了石墨烯作为增强相制备石墨烯/树脂材料(graphene/resin materials,简称GR)的方法,分析不同制备工艺的特点。系统阐述了石墨烯改性树脂材料在力学、耐热、导电和耐摩擦等性能上的研究现状,分析了添加石墨烯对树脂材料性能产生影响的规律和机理。结果表明:添加少量石墨烯填料可全面提高树脂材料的综合性能,得到较佳的改善效果。最后基于石墨烯/树脂材料的优异性能总结了石墨烯/树脂材料的应用前景和未来着重探索的方向。

关键词：石墨烯氧化石墨烯树脂基体性能研究

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高有机物含量泰妙菌素废盐的热处理研究

应用化工 2024年第1期53卷 67-70页

作者：胡雅熊萍孙秀云南京理工大学环境与生物工程学院江苏南京210014 化工污染控制与资源化江苏省高校重点实验室江苏南京210094

采用热处理工艺研究高有机物含量泰妙菌素废盐。通过分析泰妙菌素废盐无机、有机成分,考察不同气氛、温度下废盐的热解过程及废盐热解产物,确定泰妙菌素废盐的最佳热解工艺:氮气气氛、温度在500℃,继而得到热解活性炭,其总比表面积为227... 详细信息

采用热处理工艺研究高有机物含量泰妙菌素废盐。通过分析泰妙菌素废盐无机、有机成分,考察不同气氛、温度下废盐的热解过程及废盐热解产物,确定泰妙菌素废盐的最佳热解工艺:氮气气氛、温度在500℃,继而得到热解活性炭,其总比表面积为2270 m^(2)/g、微孔比表面积为1000 m^(2)/g、介孔平均孔径为6.50 nm、微孔平均孔径为0.55 nm。将高有机物含量泰妙菌素废盐经过热处理以实现废盐的资源化利用,为类似高有机物含量废盐的资源化利用提供参考。

关键词：废盐泰妙菌素热处理热解活性炭

Relationship between single nucleotide polymorphisms in the deoxycytidine kinase gene and chemosensitivity of gemcitabine in six pancreatic cancer cell lines

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Chinese Medical Journal 2011年第3期124卷 419-422页

作者： SI Shuang LIAO Quan ZHAO Yu-pei hu ya ZHANG Qiang YOU Li-li Department of General Surgery Peking Union Medical College Hospital National Laboratory of Medical Molecular BiologyChinese Academy of Medial Sciences and Peking Union Medical College Beijing 100730 China School of Public Health Peking University Health Science CenterBeijing 100191 China

Background Single nucleotide polymorphisms （SNPs） in the deoxycytidine kinase （dCK） gene are associated with chemosensitivity to nucleoside analogs. 2＇,2＇-Difluoro 2＇-deoxycytidine （gemcitabine） is a first-line nucleoside analog drug in the treatment of pancreatic cancer. However, the association between SNPs in the dCK gene and chemosensitivity to gemcitabine has not been fully established. Therefore, the present study aimed to investigate the relationship between SNPs in the dCKgene and chemosensitivity to gemcitabine in human pancreatic cancer cell lines.Methods Seven SNPs in the dCK gene were sequenced in six human pancreatic cancer cell lines. The chemosensitivity of these six cell lines to gemcitabine were evaluated in vitro with a Cell Counting Kit-8 （CCK-8） test.Inhibition rates were used to express the chemosensitivity of pancreatic cancer cell lines to gemcitabine.Results The genotype of the A9846G SNP in the dCKgene was determined in six human pancreatic cancer cell lines.The cell lines BxPC-3 and T3M4 carried the A9846G SNP genotype AG, whereas cell lines AsPC-1, Mia PaCa2, SW1990 and SU86.86 carried the GG genotype. Cell lines with the AG genotype （BxPC-3 and T3M4） were more sensitive to gemcitabine compared with cell lines with the GG genotype （AsPC-1, Mia PaCa2, SW1990 and SU86.86） and significantly different inhibition rates were observed between cell lines carrying the AG and GG genotypes （P 〈0.01）.Conclusions Variants in the A9846G SNP of the dCK gene were associated with sensitivity to gemcitabine in pancreatic cancer cell lines. The dCK A9846G SNP may act as a genetic marker to predict chemotherapy efficacy of gemcitabine in pancreatic cancer.

关键词： deoxycytidine kinase gene gemcitabine single nucleotide polymorphism chemosensitivity pancreatic neoplasm

MYB转录因子在调控植物响应逆境胁迫中的作用

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生物技术通报 2024年第6期40卷 5-22页

作者：胡雅丹伍国强刘晨魏明兰州理工大学生命科学与工程学院兰州730050 甘肃烟草工业有限责任公司技术研发中心兰州730050

MYB作为植物中最大的多功能转录因子(transcription factors,TFs)家族之一,在基因转录水平上广泛地参与调控植物生长发育、激素信号转导及逆境胁迫应答等过程。该类转录因子N端含有典型的MYB结构域,根据MYB结构域中R重复序列的数量分为... 详细信息

MYB作为植物中最大的多功能转录因子(transcription factors,TFs)家族之一,在基因转录水平上广泛地参与调控植物生长发育、激素信号转导及逆境胁迫应答等过程。该类转录因子N端含有典型的MYB结构域,根据MYB结构域中R重复序列的数量分为不同的亚组;而C端结构域差异较大,因此功能上具有多样性。大量研究表明,在受到外界环境信号的激活后,MYB可单独或通过和其他蛋白互作后,与下游靶基因启动子区域的顺式作用元件MYBCORE和AC-box结合,参与调控下游胁迫应答相关基因的表达,从而调节植物对逆境胁迫的耐受性。另外,MYB也通过参与脱落酸(abscisic acid,ABA)、油菜素内酯(brassinolide,BR)、茉莉酸(jasmonic acid,JA)和活性氧(reactive oxygen species,ROS)等信号通路的方式,对非生物胁迫以及生物胁迫做出应答反应。论文对植物MYB家族的结构与分类及其作用方式进行了归纳,重点对植物MYB参与调控响应盐、干旱、极端温度、营养亏缺、重金属以及病原菌等非生物和生物逆境胁迫的作用机制进行了综述,并对未来重点研究方向提出了展望,为今后农作物的抗逆性遗传改良和生物育种提供优异基因资源和理论支持。

关键词： MYB转录因子转录调控 DNA结合结构域非生物胁迫生物胁迫抗逆性基因表达蛋白互作

生物炭基改性材料修复土壤氯代烃污染研究进展

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应用化工 2024年第5期53卷 1180-1185页

作者：李文章李法云胡亚茹王玮上海应用技术大学生态技术与工程学院上海201418 美丽中国与生态文明研究院(上海高校智库) 上海201418 上海城市路域生态工程技术研究中心上海201418

基于我国土壤氯代烃污染现状及应用生物炭材料修复的局限性,针对生物炭性能受官能团、吸附位点数量限制和实际场地修复应用的长效性较差等问题,系统综述了生物炭不同改性方法及其对生物炭性能的改进,分析了生物炭基改性材料作为载体固... 详细信息

基于我国土壤氯代烃污染现状及应用生物炭材料修复的局限性,针对生物炭性能受官能团、吸附位点数量限制和实际场地修复应用的长效性较差等问题,系统综述了生物炭不同改性方法及其对生物炭性能的改进,分析了生物炭基改性材料作为载体固定化降解微生物菌剂的特性,并深入阐述酸碱改性、金属改性生物炭及生物炭基材料固定化微生物去除氯代烃的机理与效能,以期为生物炭作为土壤氯代烃污染修复材料提供新思路。

关键词：生物炭改性土壤修复氯代烃微生物

Physiological mechanisms of resistance to cold stress associated with 10 elite apple rootstocks

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Journal of Integrative Agriculture 2018年第4期17卷 857-866页

作者： WANG yan-xiu hu ya CHEN Bai-hong Zhu yan-fang Mohammed Mujitaba Dawuda Sofkova Svetla College of Horticulture Gansu Agricultural University Deparment of Horticulture Faculty of Agriculture University for Development Studies Institute of Agriculture and Environment Massey University

A study was conducted in attempting to identify the cold-resistant apple rootstocks and to establish a comprehensive evaluation system. In this study, 10 elite apple dwarfing rootstocks(GM256, JM7, M26, M7, SC1, SH1, SH38, SH6, M9, and T337) were employed for the experiment and the following parameters were investigated under different low temperature stress conditions(0, –15, –20, –25, –30, and –35°C): the changes of the relative electrical conductivity(REC), anthocyanin content, protein content, soluble sugar content, soluble starch content, proline content, malondialdehyde(MDA) content, superoxide dismutase(SOD) activity, and peroxidase(POD) activity of the dormant branches. The inflection temperature that could represent the plant tissue semi-lethal temperature(LT) was obtained by the measurements of REC. The LTwas used to evaluate eight other indices. The results showed that there was no significant correlation between LTand POD activity as well as between the soluble sugar, protein and proline contents at 0 and –15°C. Soluble starch content at 0 and –15°C and anthocyanin content at –15–(–30)°C were significantly but negatively correlated to the LT50 and the MDA content at 0–(–20)°C was significantly positively correlated to the LT. Statistical analysis based on principal component analysis and LT50 showed that cold resistant apple rootstocks in the decreasing order from high to low as GM256, SH6, SH38, SH1, SC1, M26, M7, JM7, T337, and M9.

关键词： cold resistance LT_(50) principal component analysis apple dwarfing rootstock