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Effect of long-term doubled CO_2 on chlorophyll-protein complexes of leaves of soybean (Glycine max L.) and millet (Setaria italica)

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chinese Science Bulletin 1997年第16期42卷 1403-1407页

作者： WANG Kebin, LOU shiqing, ZHAO Fuhong, DAI Yunling and kuang {3. of {3., chinese academy of sciences, Beijing 100093. China Institute of botany Chinese Academy of Sciences Beijing China

OWING to the burning of fossil fuels, cutting down trees in forests, etc., the global

关键词： doubled CO2 concentration photosynthesis chlorophyll-protein complex photosystem Ⅱ light-harvesting chlorophyll a/b-protein (LHC Ⅱ ).

Honeycomb-like MoCo alloy on 3. nitrogen-doped porous graphene for efficient hydrogen evolution reaction

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Rare Metals 2024年第3期43卷 1072-1082页

作者： lin-Ping Wang kuang Li Hua-Long Ding Le Xu Chen Huang Jiao-Jiao Zhou Cong-Taowen Pei-lin Zhang Wei-Wei Wang Lu-Yang Chen Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai200237China State Key Laboratory of High-Performance Ceramics and Superfine Microstructure Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai200050China State Key Laboratory of Chemical Engineering and School of Chemistry and Molecular Engineering East China University of Science and TechnologyShanghai200237China

An efficient electrocatalyst is indispensable to significantly reduce energy consumption and accelerate the conversion efficiency of water *** this work,the honeycomb-like porous MoCo alloy on nitrogen-doped three-dimensional(3.)porous graphene substrate(Mo_(0.3.Co_(0.7)@NPG)has been synthesized from the annealing of layered double hydroxide(MoCo-LDH@NPG).Especially,the Mo_(0.3.Co_(0.7)@NPG exhibits low hydrogen evolution overpotential of 75 mV(10 mA·cm^(-2))and a Tafel slope of 69.9 mV·dec^(-1),which can be attributed to highly conductive NPG substrate,the unique nanostructure and the synergistic effect of Mo and ***,the Mo_(0.3.Co_(0.7)@NPG can maintain the original morphology and high catalytic activity after 50-h stability *** work proposes a general strategy to synthesize a multi-element alloy on conductive substrates with high porosity for electrocatalytic reaction.

关键词： MoCo alloy Three-dimensional nitrogen-doped porous graphene Hydrogen evolution reaction(HER)

Mg^(2+)-induced LHC Ⅱ aggregation in thylakoid membrane

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chinese Science Bulletin 1999年第10期44卷 916-919页

作者： wen xiaogang, lin shiqing and kuang tingyuninstitute of botany , chinese academy of sciences , Beijing 100093. China

Mg2+-induced changes in 77K fluorescence spectra of wheat thylakoid membranes were analyzed by a Gaussian deconvolution program. All spectra were fitted well with 7 Gaussian sub-bands. The sub-band areas for the LHC Ⅱ macroaggregate (F699) and PS Ⅱ (F685and F695) were increased and those for the LHC Ⅱ trimer (F681) and PS Ⅰ (F729 and F740) were decreased by Mg2+ . Moreover, it was found that the sub-band area ratio f699 over F681 was dramatically enhanced by Mg2+ by 1.72 times. It was concluded that the LHC Ⅱ trimer in thylakoid membranes could be aggregated and transformed into its macroaggregate by Mg2+ on a large scale. The possible implication of the Mg2+-induced LHC Ⅱ aggregation was also discussed.

关键词： LHCⅡ aggregation Mg2+ fluorescence spectra deconvolution.

基于遥感降水产品的西南地区降水时空动态分析

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水土保持研究 2024年第5期31卷 265-278页

作者：张寒博窦世卿温颖广东省科学院广州地理研究所广州510308 桂林理工大学测绘地理信息学院广西桂林541006 长安大学地质工程与测绘学院西安710054

[目的]探究遥感降水产品在西南地区的适用性,揭示区域降水时空特征,为西南地区旱涝灾害评估及水资源利用等提供科学参考依据。[方法]首先结合西南地区内100个地面气象站点降水数据,从多年平均和年际两种时间尺度以及气象站点空间尺度评... 详细信息

[目的]探究遥感降水产品在西南地区的适用性,揭示区域降水时空特征,为西南地区旱涝灾害评估及水资源利用等提供科学参考依据。[方法]首先结合西南地区内100个地面气象站点降水数据,从多年平均和年际两种时间尺度以及气象站点空间尺度评价了2001—2019年TRMM降水产品和GPM降水产品的适用性,然后基于优选的降水产品,采用变异系数法、Theil-Sen Median趋势分析耦合Mann-Kendall显著性检验方法及Hurst指数法进行降水时空变化及其可持续性分析,并预测了未来降水趋势。[结果](1)GPM,TRMM在西南地区均表现出较好的一致性和适用性,虽然都存在一定的高估现象,但GPM的降水空间细节表征能力优于TRMM,在整体上更接近实测数据。(2)19年间西南地区整体降水波动变化并不突出,主要表现出较低波动变化和中等波动变化,共占全域的87.54%;近19年西南地区降水变化趋势整体上表现为增加,降水增加区域占全域的83.71%,降水变化趋势以弱(50.3.%)、中(24.3.%)持续性为主;未来西南地区62.24%的区域降水趋势将持续增加,主要分布在西南地区中部和北部地区,13.23.的区域降水趋势将持续减少,主要分布在云南中部和四川西南部地区。[结论]GPM比TRMM更适合表征西南地区的降水特征,能有效用于开展降水的时空动态分析。

关键词： GPMIMERG TRMM3.B43 遥感技术适用性评价时空动态分析

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粤东河源盆地的深部构造、沉积序列与盆地演化

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地球学报 2024年第3期45卷 291-308页

作者：张敏李海龙唐灵祁士华旷健王文张金龙广东省有色金属地质局九三五队广东惠州516001 中国地质科学院北京100037 中国地质大学(武汉)生物地质与环境地质国家重点实验室湖北武汉430074

粤东河源盆地是东南沿海规模较大的晚中生代—新生代陆相盆地之一,发育有较为完整的晚白垩世—新近纪地层。研究该盆地的深部构造、控盆断裂、沉积序列和盆地的形成发展,对于认识东南沿海晚中生代—新近纪的大地构造演化有重要意义。通... 详细信息

粤东河源盆地是东南沿海规模较大的晚中生代—新生代陆相盆地之一,发育有较为完整的晚白垩世—新近纪地层。研究该盆地的深部构造、控盆断裂、沉积序列和盆地的形成发展,对于认识东南沿海晚中生代—新近纪的大地构造演化有重要意义。通过对野外地质调查、地球物理反射剖面和约两千米的地质科学钻探等数据资料的综合研究,查明了河源盆地为中生代—新生代沉积断陷盆地,地层结构清晰,沉积基底为早古生代地层,并建立了该盆地晚白垩世—新近纪的三阶段沉积序列;该盆地发育渐新世的火山岩,揭示了控盆边界断裂及内部构造发育特征,暗示了原型盆地的破坏发生于晚新生代:即盆地南北两侧紫金—博罗逆冲断层和河源断裂带在晚古近纪—新近纪强烈地改造了原型盆地;基于以上认识,初步恢复了河源盆地的形成演化历史,构建了河源盆地沉积序列-构造演化模式。

关键词：河源盆地沉积序列反射地震构造演化控盆断裂科学钻探东南沿海

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高光谱成像技术结合集成学习的金钗石斛氮素检测

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光谱学与光谱分析 2024年第7期44卷 1918-1927页

作者：匡润龙腾刘海林吴继辉吕金胜谢自然刘文涛兰玉彬龙拥兵王再花赵静华南农业大学电子工程学院(人工智能学院) 广东广州510642 广东省农业科学院环境园艺研究所/广东省园林花卉种质创新综合利用重点实验室广东广州510640 国家精准农业航空施药技术国际联合研究中心广东广州510642 岭南现代农业科学与技术广东省实验室广东广州510642

金钗石斛叶片氮素含量是实现其精准施肥的重要决策依据之一。传统的氮素含量检测方法耗时且有损样品,如何高效检测金钗石斛叶片氮素含量是种植企业日益关心的问题。为了快速、无损获取金钗石斛叶片氮素含量,以金钗石斛新鲜叶片为实验样... 详细信息

金钗石斛叶片氮素含量是实现其精准施肥的重要决策依据之一。传统的氮素含量检测方法耗时且有损样品,如何高效检测金钗石斛叶片氮素含量是种植企业日益关心的问题。为了快速、无损获取金钗石斛叶片氮素含量,以金钗石斛新鲜叶片为实验样品,在获取其402.6~1005.5 nm高光谱图像和氮素化学检测值后,经感兴趣区域(ROI)分割、光谱预处理,利用偏最小二乘回归(PLSR)、核岭回归(KRR)以及支持向量回归(SVR)等三种个体学习器算法,以及随机森林(RF)、Bagging和Adaboost等三种集成学习算法,针对金钗石斛的氮素含量进行建模。在此基础上构建基于金钗石斛新鲜叶片全波段光谱信息、经过竞争自适应加权算法(CARS)特征提取的特征波段光谱信息的回归预测模型,并进行预测精度对比。结果表明,在基于全波段光谱信息构建模型时,经过多项式平滑算法(SG)预处理的光谱数据建立的RF模型最佳(R_(CV)^(2)=0.9614、RMSE_(CV)=0.0818、R_(P)^(2)=0.9726、RMSE_(P)=0.063.),所有模型R^(2)都达到了0.90以上。基于CARS提取的特征波段构建回归预测模型,Bagging模型具有最高的精确度和稳定性,其中SG-CARS-Bagging预测效果最好(R_(CV)^(2)=0.93.7、RMSE_(CV)=0.1000、R_(P)^(2)=0.953.、RMSE_(P)=0.0826),而个体学习器中的KRR和SVR模型精度明显下降。经过CARS算法特征提取去掉了一些重要波段,提高了建模的效率,但是模型的精度有所降低。因此在优化回归模型的特征参数时,必须始终考虑精度和效率之间的平衡。结果表明,RF、Bagging和Adaboost等集成算法比PLSR、KRR和SVR个体学习器算法具有更高的稳定性和预测精度,更适用于高光谱数据的分析与处理,在金钗石斛氮素营养监测方面具有明显优势。

关键词：高光谱金钗石斛集成学习氮素 CARS

N-PERFLUOROALKANESULFONYL SULFILIMINES:SYNTHESIS AND X-RAY STRUCTURE ANALYSIS

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chinese Chemical Letters 1992年第9期3卷 703-706页

作者： Shi Zheng ZHUa Ai wen LI~a kuang WU~b a Shanghai Institute of Organic Chemistry,chinese {3. of {3.,3.5 lingling Lu,Shanghai,20003. b Analysis & Measurement Center,FuDan University,220 Handan Lu,20043.

N-Perfluoroalkanesulfonyl S,S-dialkyl sulfilimines R_fSO_2N=SR^1R^2 were prepared in high yields by condensation of N-sulfinylperfluoroalkane- sulfonamides R_fSO_2NSO with *** X-ray structrue analysis of R_fSO_2N=SMe_... 详细信息

关键词： N-PERFLUOROALKANESULFONYL SULFILIMINES length

Rise of the ethylene biosynthesis machinery from the Cβ-S lyase

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Molecular Plant 2022年第5期15卷 784-787页

作者： Mengchen Tong Chi-kuang wen National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesInstitute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China

1-aminocyclopropane-1-carboxylic acid(ACC),produced from S-adenosyl-methionine(SAM)by ACC synthase(ACS),is oxidized by ACC oxidase(ACO)to produce the gaseous plant hormone ethylene in seed plants(Kende,1993..

关键词： oxidized machinery gaseous

Upconversion Photoluminescence and Energy Transfer Mechanism of a Novel Terbium-mercury Compound

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chinese Journal of Structural Chemistry 2019年第6期38卷 1012-1020页

作者： lin Wei-Sheng kuang Han-Mao LUO Hui CHEN wen-Tong Department of Ecological and Resources Engineering Fujian Key Laboratory of Eco-industrial Green TechnologyWuyi UniversityWuyishanFujian 354300China Institute of Applied Chemistry School of Chemistry and Chemical EngineeringJiangxi Province Key Laboratory of Coordination ChemistryJinggangshan UniversityJi'an 343009China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

A novel terbium-mercury complex [Tb(IA)3.H3.O)2]2 n(2 n HgCl4)(n Hg2 Cl5)·n H3.O· 3.n H2 O(1, HIA = isonicotinic acid) has been synthesized through hydrothermal reactions and characterized by single-crystal X-ray diffraction. Complex 1 crystallizes in the C2/c space group of monoclinic system with a = 24.23.7(5), b = 20.83.2(6), c = 15.3.06(3. ?, β = 128.257(2)°, V = 6074.3.2) ?3. C3.H41Cl13.g4N6O20Tb2, Mr = 2458.80, Z = 4, Dc = 2.689 g/cm3. μ(Mo Kα) = 13.014 mm–1 and F(000) = 4520. The crystal structure of 1 is characterized by a one-dimensional(1-D) chain-like structure. Solid-state UV/Vis diffuse reflectance spectrum reveals the existence of a wide optical band gap of 3.3. eV. Solid-state photoluminescence experiment uncovers that it shows reddish brown upconversion emission. The emission bands are originated from the characteristic emission of the 4 f electrons intrashell transition of the 5D4 → 7 FJ(J = 6, 5, 4) of the Tb3. ions. Energy transfer mechanism is explained by the energy level diagram of the Tb3. ion and the isonicotinic acid ligand. It shows a remarkable CIE chromaticity coordinates(0.4158, 0.4005).

关键词： crystal CIE energy transfer mechanism photoluminescence terbium