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The Physiological and Molecular Responses of Exogenous Selenium to Selenium Content and Fruit Quality in Walnut

Phyton-International Journal of Experimental Botany 2023年第3期92卷 851-860页

作者： mufang sun Xinran Hui Cuiling Tong Longyi Yuan Dejian Zhang Xinyang Agriculture and Forestry University Xinyang464000China Tibet Plateau Walnut Industry Research Institute Yangtze UniversityCollege of Horticulture and GardeningJingzhou434025China Jingzhou Institute of Technology Jingzhou434025China

To study the effect of exogenous selenium on fruit quality in walnut(Juglans regia L.),8-year-old walnut(Qingxiang)was taken as the research *** the fruit expansion stage,300 mg/L of sodium selenate,yeast selenium and sodium selenite solutions were applied on the leaf of walnut,and the selenium levels in leaves,pericarp and kernel were determined at the ripening *** fruit quality,mineral nutrient content,antioxidant enzyme activity,and related genes’expression were *** results showed that the three exogenous selenium increased the selenium levels in leaves,pericarp and kernel of *** also significantly increased fruit and kernel weights,and kernel linoleic acid,but markedly decreased kernel crude fat and saturated fatty *** spraying promoted the absorption of mineral nutrients such as potassium and zinc,but inhibited the absorption of calcium,and had no significant effect on iron and magnesium in the *** exogenous selenium increased the activities of superoxide dismutase(SOD),peroxidase(POD),ascorbate peroxidase(APX),and catalase(CAT)significantly in the *** for sodium selenate treatment significantly reduced malondialdehyde(MDA)content in the kernel,the other two selenium sources treatments had no significant effect on MDA and hydrogen peroxide(H2O2)*** also increased the expression of JrCu/Zn-SOD,Jr2-Cys POD,JrCyt-APX and JrCAT in kernel,to different *** implies that,in the walnut fruit enlargement period,the foliar spraying selenium could increase the selenium content of walnut,affect the mineral nutrient absorption,improve the antioxidant capacity and related genes’expression,and reduce the degree of peroxide,and then improve the quality of ***,yeast selenium showed the comprehensive effect of the best.

关键词： Antioxidant system fruit quality mineral nutrient selenium walnut

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不同采摘期白化茶的品质分析

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绿色科技 2024年第11期26卷 147-150页

作者：陈凌芝孔亚帅陈义孙慕芳信阳农林学院茶学院/河南省豫南茶树资源综合开发重点实验室河南信阳464000

茶叶的采摘期与成茶品质密切相关,以不同采摘期的白叶1号鲜叶为原料,在同一加工工艺下制成绿茶,进行茶多酚、儿茶素类物质等品质成分的分析。结果表明:随采摘期的延后白化茶的茶多酚、游离氨基酸和黄酮类物质含量呈现先上升后降低的趋势... 详细信息

茶叶的采摘期与成茶品质密切相关,以不同采摘期的白叶1号鲜叶为原料,在同一加工工艺下制成绿茶,进行茶多酚、儿茶素类物质等品质成分的分析。结果表明:随采摘期的延后白化茶的茶多酚、游离氨基酸和黄酮类物质含量呈现先上升后降低的趋势,咖啡碱含量呈现升高-降低-升高趋势,可溶性糖含量呈逐渐下降趋势。儿茶素总量在不同采摘期间基本呈显著差异,表现为:4月12日>4月1日>4月17日>4月22日>4月6日。4月6日的白化茶表现出游离氨基酸含量高、茶多酚含量低的特征,其他内含物质较为丰富,所制绿茶品质优良。不同采摘期白化茶的品质成分含量有一定差异,从而影响成茶品质,综合来看以4月6日的鲜叶制作白化茶品质较佳。

关键词：白化茶采摘期理化成分儿茶素

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冲泡方式对白牡丹茶汤品质成分及感官品质的影响

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保鲜与加工 2024年第9期24卷 116-122页

作者：陈凌芝孔亚帅史猛王晶晶张向娜陈义孙慕芳尹鹏信阳农林学院茶学院河南省豫南茶树资源综合开发重点实验室河南信阳464000 湖南农业大学茶学教育部重点实验室湖南长沙410128

以白牡丹茶为对象,探究不同冲泡方式下白牡丹茶主要品质成分的浸出规律,并对滋味和汤色进行感官评价。从日常品饮角度,选取冲泡方式(盖碗泡、闷泡、煮泡)和冲泡时间(1、2、3、4、5、6 min)2个因素,研究其对白牡丹茶汤中茶多酚、咖啡碱... 详细信息

以白牡丹茶为对象,探究不同冲泡方式下白牡丹茶主要品质成分的浸出规律,并对滋味和汤色进行感官评价。从日常品饮角度,选取冲泡方式(盖碗泡、闷泡、煮泡)和冲泡时间(1、2、3、4、5、6 min)2个因素,研究其对白牡丹茶汤中茶多酚、咖啡碱和儿茶素类物质等品质成分及感官品质的影响。结果表明:不同冲泡方式下白牡丹茶的感官品质及品质成分含量存在差异,随着冲泡时间的延长,品质成分的浸出量整体呈增加趋势,但其浸出速率趋缓。综合感官品质和品质成分含量来看,茶水比为1∶50(g/mL)时,盖碗冲泡4~6 min品质为佳,闷泡3~5 min为佳,煮泡方式应在1 min左右。煮泡可通过减少投茶量等方法,降低茶多酚、咖啡碱和儿茶素类物质的过量浸出以提升茶汤品质。该研究结果可为白牡丹茶的科学泡饮提供参考。

关键词：白牡丹茶冲泡方式品质成分滋味汤色

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海拔对信阳毛尖茶生化成分的影响

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食品研究与开发 2024年第15期45卷 53-58页

作者：陈凌芝孔亚帅张向娜王晶晶赵冰心孙慕芳王晓尹鹏郭桂义信阳农林学院茶学院、河南省豫南茶树资源综合开发重点实验室河南信阳464000 信阳市文新茶叶有限责任公司河南信阳464000 湖南农业大学茶学教育部重点实验室湖南长沙410128

为探究信阳毛尖茶生化成分与海拔的关系,该研究以不同海拔的信阳毛尖茶为对象,测定茶样的主要生化成分含量,并结合多元统计分析,明确不同海拔信阳毛尖茶的生化成分差异。结果表明,低海拔茶样中游离氨基酸、没食子酸、儿茶素、表儿茶素... 详细信息

为探究信阳毛尖茶生化成分与海拔的关系,该研究以不同海拔的信阳毛尖茶为对象,测定茶样的主要生化成分含量,并结合多元统计分析,明确不同海拔信阳毛尖茶的生化成分差异。结果表明,低海拔茶样中游离氨基酸、没食子酸、儿茶素、表儿茶素、表儿茶素没食子酸酯和非酯型儿茶素含量更高,咖啡碱、黄酮类物质、表没食子儿茶素、表没食子儿茶素没食子酸酯、酯型儿茶素和儿茶素总量在高海拔茶样中含量更高;多元统计分析表明,信阳毛尖茶可根据海拔进行区分,儿茶素、表没食子儿茶素没食子酸酯、非酯型儿茶素和酯型儿茶素是区分不同海拔信阳毛尖茶的关键差异性成分。

关键词：信阳毛尖茶海拔生化成分正交矫正偏最小二乘法判别分析差异

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白毫早鲜叶茶多酚氧化酶酶学特性

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贵州农业科学 2014年第6期42卷 140-143页

作者：孙慕芳张洁郭桂义信阳农林学院茶学系河南省高校信阳毛尖茶产业工程技术研究中心信阳市茶产业基础研究重点实验室河南信阳464000 安徽省大别山区农林特色产业协同创新中心安徽合肥230061

为了解白毫早鲜叶中的PPO酶学特性,采用分光光度法,研究底物浓度、温度和pH对白毫早鲜叶PPO活性的影响以及PPO的热稳定性。结果表明:PPO活性随着温度、pH的增大呈先增大后减少的钟形曲线关系,其最适温度为40℃,最适pH为6.0;其耐热性较强... 详细信息

为了解白毫早鲜叶中的PPO酶学特性,采用分光光度法,研究底物浓度、温度和pH对白毫早鲜叶PPO活性的影响以及PPO的热稳定性。结果表明:PPO活性随着温度、pH的增大呈先增大后减少的钟形曲线关系,其最适温度为40℃,最适pH为6.0;其耐热性较强,于80℃处理1min可钝化酶活力。酶促反应在温度37℃、pH 5.6柠檬酸-磷酸缓冲液、邻苯二酚为底物条件下,Km值和Vmax分别为0.621 7mol/L和4.46U/min。

关键词：白毫早鲜叶多酚氧化酶特性

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Divergent responses of runoff to climate change in the upper basins of the Third Pole dominated by westerlies and monsoon

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Science China Earth Sciences 2024年第8期67卷 2592-2614页

作者： Qikai sun Fengge SU He sun State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100101China

The diverse climates,distribution of snow and glaciers,and geographic locations directly affect the runoff response to climate change in the upper basins of the Third *** present,a comprehensive analysis of runoff variations and their distinct responses to climate change in the westerlies-and monsoon-dominated upper basins is still *** study comprehensively analyzed annual runoff variations in westerlies-dominated basins(the upper basins of the Aksu(UAKS),Syr Darya(USRD),Yarkant(UYK),Hotan(UHT),Amu Darya(UAMD),and Indus(UI))and monsoon-dominated basins(the upper basins of the Yangtze(UYA),Yellow(UYE),Lancang(ULC),Nujiang(UNJ),and Yarlung Zangbo(UYZ))of the Third Pole from 1961 *** multi-source meteorological data and large-scale circulation factors,this study investigated the divergent responses of runoff in the upper basins to climate change,and explored the large-scale circulation mechanisms underlying runoff variations in these upper *** results showed that:(1)The annual runoff in the majority of upper basins(except for the UYE and UYZ)exhibited an increasing trend,and the annual runoff in the UAKS,UYK,and UI showed a significant increasing trend from1961 to *** annual runoff in the upper basins of the Third Pole changed abruptly from decreasing to increasing between the 1980s and 2000s,with the exception of the UYE.(2)The runoff in the monsoon-dominated upper basins has been controlled primarily by changes in precipitation over the past 55 *** contrast,the runoff in the westerlies-dominated upper basins exhibited three distinct long-term responses to climate change:temperature-dominated(UYK and UHT),precipitation-dominated(USRD and UAMD),and the combined influence of precipitation and temperature(UAKS and UI).Since the 1960s,the sensitivity of runoff to warm season temperature changes in the most westerlies-dominated upper basins has decreased,while the response of runoff to precipitation changes has intensified.(3)The stud

关键词： Upper basins of the Third Pole Climate change Westerlies and monsoon Runoff variations Large-scale circulation factors

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New perspectives on deep carbon cycling

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Science China Earth Sciences 2024年第8期67卷 2411-2422页

作者： Weidong sun Center of Deep Sea Research Key Laboratory of Ocean Observation and ForecastingInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laoshan Laboratory Qingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

The proto-atmosphere serves as a crucial starting point for the carbon *** based on atmospheric data from Mars and Venus suggest that Earth's proto-atmosphere contained>110 bar of CO_(2)and>2.6 bar of *** protoatmosphere had over 1000 bar of water vapor during the magma ocean stage,assuming the proto-ocean had a volume of two oceans of *** this stage both water and carbon dioxide were in a supercritical state at the magma-atmosphere *** serpentinization reactions occurred due to rock-water interaction,producing abundant ***,nitrogen is reduced to ammonia,and carbon dioxide to methane,forming carbonate *** proto-atmosphere dominated by methane,ammonia,and hydrogen formed a significant amount of amino acids through *** process is essential not only to the origin of life,but also to the early carbon-nitrogen cycle on *** the Hadean eon,a large amount of CO_(2)was sequestered as carbonate and organic ***,it mainly entered the deep mantle through mantle overturn or *** the mantle transition zone,carbonate undergoes“Redox freezing”,where carbonate is reduced to diamond through oxidation of ferrous iron in the *** the lower mantle,Fe^(2+)undergoes disproportionation reactions,forming Fe^(3+)and metallic *** these,Fe^(3+)mainly resides in bridgmanite,thereby increasing the oxygen fugacity of the lower mantle,while metallic iron falls to the Earth's *** distribution of carbon in the mantle is crucial for deep carbon *** density curves of diamond and mantle peridotite melt intersect at the bottom of the mantle transition zone(about 660 km).This density crossover leads to the accumulation of diamond during the magma ocean *** materials such as subducting slabs enter the lower mantle,compensatory upwelling of lower mantle material *** enters the upper mantle,decomposes,releasing Fe^(3+)ions and oxidizes diamond

关键词： Carbon cycling Proto-atmosphere Amino acids Subduction initiation Passive margin subduction Atmospheric carbon dioxide

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Fossil Equidae in the Linxia Basin with Biostratigraphic and Paleozoogeographic Significance

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 1-9页

作者： sun Boyang Key Laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China

The Linxia Basin is characterized by an abundance of Cenozoic sediments,that contain exceptionally rich fossil *** are abundant in the Linxia Basin,the fossil record of equids in this region including 16 species that represent 10 *** comparison to other classic late Cenozoic areas in China,the Linxia Basin stands out,because the fauna and chronological data accompanying Linxia equids render them remarkably useful for *** anchitheriines in the region,such as Anchitherium and Sinohippus,represent early equids that appeared in the late stages of the middle and late Miocene,*** the equines,most species of Chinese hipparions have been identified in the Linxia Basin and some species of the genera Hipparion and Hippotherium have FAD records for ***,Equus eisenmannae is one of the earliest known species of Equus in the Old World and is well-represented at the Longdan *** species with precise geohistorical distributions can serve as standards for high-resolution chronological units within this *** at the eastern margin of the Tibetan Plateau and subject to considerable uplift,the Linxia Basin has served as a biogeographic transition area for equids throughout the late Cenozoic.

关键词： Equidae Cenozoic biostratigraphy paleozoogeography Linxia Basin

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Achieving simultaneously high conversion and high selectivity for light olefins directly producing from syngas

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Science China Chemistry 2024年第3期67卷 753-754页

作者： Yuhan sun Shanxi Research Institute Huairou Research LaboratoryTaiyuan 030032China Institute of Carbon Neutrality ShanghaiTech UniversityShanghai 201210China

The activity and selectivity are two primary indexes of a successful catalyst for chemical reactions. However,achieving a high activity and a high selectivity simultaneously is a long-standing challenge in catalysis, the socalled activity-selectivity trade-off. In the article recently published in Science, a research team led by Prof.

关键词： selectivity simultaneous catalysis

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ONE-PARAMETER FINITE DIFFERENCE METHODS AND THEIR ACCELERATED SCHEMES FOR SPACE-FRACTIONAL SINE-GORDON EQUATIONS WITH DISTRIBUTED DELAY

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Journal of Computational Mathematics 2024年第3期42卷 705-734页

作者： Tao sun Chengjian Zhang Haiwei sun School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Engineering Modeling and Scientific Computing Huazhong University of Science and TechnologyWuhan 430074China Department of Mathematics University of MacaoMacaoChina

This paper deals with numerical methods for solving one-dimensional(1D)and twodimensional(2D)initial-boundary value problems(IBVPs)of space-fractional sine-Gordon equations(SGEs)with distributed *** 1D problems,we construct a kind of oneparameter finite difference(OPFD)*** is shown that,under a suitable condition,the proposed method is convergent with second order accuracy both in time and *** implementation,the preconditioned conjugate gradient(PCG)method with the Strang circulant preconditioner is carried out to improve the computational efficiency of the OPFD *** 2D problems,we develop another kind of OPFD *** such a method,two classes of accelerated schemes are suggested,one is alternative direction implicit(ADI)scheme and the other is ADI-PCG *** particular,we prove that ADI scheme can arrive at second-order accuracy in time and *** some numerical experiments,the computational effectiveness and accuracy of the methods are further ***,for the suggested methods,a numerical comparison in computational efficiency is presented.

关键词： Fractional sine-Gordon equation with distributed delay One-parameter finite difference methods Convergence analysis ADI scheme PCG method

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