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Effects of 1-Methylcyclopropene on NO Content,NOS Activity,and H_2O_2 Content in Postharvest Suli Pears

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Agricultural Sciences in China 2011年第5期10卷 797-804页

作者： DONG Yu LIU Li-qin guan jun-feng Institute of Genetics and Physiology Hebei Academy of Agricultural and Forestry Sciences Shijiazhuang 050051 P.R.China College of Life Science Hebei Normal University Shijiazhuang 050016 P.R.China

Studies were conducted over the effects of 1-methylcycolpropene （1-MCP） treatment on postharvest life of Suli pears （Pyrus bretschneideri Rehd.） stored at room and cold temperatures on nitric oxide （NO）,nitric oxide synthase （NOS） activity,and hydrogen dioxide （H2O2）.Results showed that the 1-MCP treatment had little effect on total soluble solids （TSS） at both room and cold temperatures.1-MCP delayed softening of Suli pear fruits,decreased respiratory rate and H2O2 accumulation,and increased NO and NOS activity at room temperature storage,while the effect of cold temperature storage was relatively *** was a significant positive correlation between NOS activity and NO *** is concluded that 1-MCP had effects on endogenous NO content and accumulation of ***,H2O2 acting as a signaling molecule via regulating NO level affects the ripening and senescence of Suli pears.

关键词： pear 1-MCP NO NOS H2O2

Effects of 1-methylcyclopropene and modified atmosphere packaging on fruit quality and superficial scald in Yali pears during storage

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Journal of Integrative Agriculture 2018年第7期17卷 1667-1675页

作者： feng Yun-xiao CHENG Yu-dou HE Jin-gang LI Li-mei guan jun-feng Institute of Genetics and Physiology Hebei Academy of Agriculture and Forestry SciencesShijiazhuang 050051P.R.China Plant Genetic Engineering Center of Hebei Province Shijiazhuang 050051P.R.China

The Yali pear（Pyrus bretschneideri Rehd.） is susceptible to superficial scald during prolonged cold storage and at shelf life. This study investigated the effects of 1-methylcyclopropene（1-MCP） and modified atmosphere packaging（MAP） on changes of fruit quality and superficial scald during cold storage and at shelf life in Yali pear. Compared with MAP, the combination of MAP and 1-MCP（MAP＋1-MCP） treatment reduced the carbon dioxide and ethylene content inside the packaging bag. The 1-MCP, MAP, and MAP＋1-MCP treatments reduced the superficial scald index, malondialdehyde content, O2^-· production rate and relative conductivity and inhibited the accumulation of α-farnesene and conjugated trienes in the peel. 1-MCP and MAP＋1-MCP treatments maintained a higher phenolic content and enhanced the catalase and superoxide dismutase activities in the fruit, while reduced activities of lipoxygenase and polyphenol oxidase in the peel preceding the onset of superficial scald. Comprehensive analysis indicated that the MAP＋1-MCP treatment is the most effective method tested for improving the quality of Yali pears during cold storage and at shelf life.

关键词： pear 1-methycyclopropene modified atmosphere packaging superficial scald browning

Changes of chlorogenic acid content and its synthesis-associated genes expression in Xuehua pear fruit during development

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Journal of Integrative Agriculture 2017年第2期16卷 471-477页

作者： HE Jin-gang CHENG Yu-dou guan jun-feng GE Wen-ya ZHAO Zhe Institute of Genetics and Physiology Hebei Academy of Agricultural and Forestry Science Shijiazhuang 050051 P.R. China Plant Genetic Engineering Center of Hebei Province Shijiazhuang 050051 P.R. China

According to synthetic pathway of plant chlorogenic acid （CGA）, the expression patterns of genes encoding enzymes that are associated with CGA synthesis were studied in normally developed Xuehua pear fruit. The study demonstrated that CGA content in peel and flesh of Xuehua pear decreased as fruit development progressed, with a higher level in peel. The expression levels of PbPAL 1, PbPAL2, PbC3H, PbC4H, Pb4CL 1, Pb4CL2, Pb4CL6, PbHC T1 and PbHC T3 genes decreased in fruit, which was consistent with the pattern of variation in CGA content. That indicated that these genes might be key genes for influencing fruit CGA synthesis in Xuehua pear. However, Pb4CL7 gene expression profile is not consistent with variation of CGA content, hence, it may not be a key gene involved in CGA synthesis.

关键词： cinnamate 4-hydroxylase gene hydroxy cinnamoyl CoA shikimate/quinic acid hydroxycinnamoyl transferasegene p-coumarate 3'-hydroxylase gene 4-hydroxycinnamoyl-CoA ligase gene phenylalanine ammonia lyasegene Xuehua pear

The Relationship Between Senescence and Ca^(2+)-ATPase Activity of Microsomal Membrane and Lipid Peroxidation in Harvested Peach Fruit

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Agricultural Sciences in China 2006年第8期5卷 609-614页

作者： guan jun-feng FAN Xiu-cai DOU Shi-juan ZHANG Ji-shu LI guang-min Institute Of Genetics and Physiology Hebei Academy of Agricultural and Forestry Sciences Shijiazhuang 050051 P.R.China Zhengzhou Fruit Institute Chinese Academy of Agricultural Sciences Zhengzhou 450002 P.R.China Northwest A＆F University Yangling 712100 P.R.China

Peach fruit easily soften and have a short storage time at normal temperature. In this study, peach fruit （Prunus persica sieb et Zucc cv. Yingqing） were picked and stored at 25 and 4℃ to investigate the senescence in correlation with Ca^2＋- ATPase activity of microsomal membrane and lipid peroxidation during ripening and senescence. In comparison with that stored at 25~C, the fruit stored at 4℃ exhibited a higher flesh firmness, lower respiration rate, and generated the late bigger peak value of Ca^2＋-ATPase activity as well as maintained the higher activity of the enzyme. Meanwhile, the lower levels of super oxygen radical （O2^-.） production and content of malondialdehyde （MDA）, a product of membrane lipid peroxidation were observed. Sodium orthovanadate （SO） and erythrosin B （EB）, as Ca^2＋-ATPase inhibitors, could stimulate the respiration rate. The results suggested that the slower senescence rate of peach fruit was closely related to the higher peak value and longer duration of Ca^2＋-ATPase activity in microsomal membrane, with the slighter membrane lipid peroxidation and lower O2^-. production rate.

关键词： peach fruit Ca^2+-ATPase active oxygen lipid peroxidation senescence

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我国西部大开发中的资源观问题

地理学与国土研究 2001年第1期17卷 1-5页

作者：关凤峻北京大学城市与环境学系博士后流动站北京100871

该文指出我国西部具有明显的资源优势 ,资源是西部大开发的核心。应在保护中开发 ,在开发中保护 ,资源开发与环境保护并不总是对立的 ,发展才是硬道理 ,知识经济在我国初见端倪 ,2 1世纪初自然资源仍然是支撑我国经济增长的基础 ,阐明... 详细信息

该文指出我国西部具有明显的资源优势 ,资源是西部大开发的核心。应在保护中开发 ,在开发中保护 ,资源开发与环境保护并不总是对立的 ,发展才是硬道理 ,知识经济在我国初见端倪 ,2 1世纪初自然资源仍然是支撑我国经济增长的基础 ,阐明新老资源观是连续的 ,并不是对立的观点。

关键词：资源开发资源观西部大开发自然资源环境保护

钙拮抗剂对呼吸跃变后苹果组织乙烯生成的影响(简报)

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植物生理学通讯 2001年第1期37卷 17-18页

作者：关军锋河北省农林科学院农业物理生理生化研究所石家庄050051

异博定、La3 + 和Ca2 + 对呼吸跃变后苹果 (品种辽伏 )圆片的乙烯生成影响不显著 ,高浓度钌红 (2mmol·L-1)显著抑制乙烯生成 ,而较低浓度的钌红 (0 .2 5mmol·L-1)则促进ACC向乙烯的转化。

关键词：苹果乙烯钙钙拮抗剂呼吸跃变

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混凝土正交各向异性统计损伤本构模型研究

水利学报 2014年第5期45卷 607-618页

作者：白卫峰张树珺管俊峰陈健云华北水利水电大学河南郑州450011 南阳理工学院河南南阳473004 大连理工大学辽宁大连116024

基于统计损伤理论,本文建立了混凝土三维正交各向异性统计损伤本构模型,用于描述混凝土复杂荷载环境下的力学行为。该模型将单轴拉伸、压缩作为最基本的宏观破坏模式,复杂应力状态下的本构行为理解为2种基本模式的组合形式,考虑断裂、... 详细信息

基于统计损伤理论,本文建立了混凝土三维正交各向异性统计损伤本构模型,用于描述混凝土复杂荷载环境下的力学行为。该模型将单轴拉伸、压缩作为最基本的宏观破坏模式,复杂应力状态下的本构行为理解为2种基本模式的组合形式,考虑断裂、屈服两种细观损伤机制。提出新的"等效应变"假设,通过引入等效传递拉损伤应变和损伤影响参数,建立起复杂应力状态损伤演化过程与单轴损伤演化过程之间的等效关系。通过预测值与试验结果比较,表明该模型能够模拟多轴加载情况下材料均匀损伤阶段本构行为的主要力学特征,从变形特性、强度特征和破坏形式等角度对材料的损伤机制进行探讨。

关键词：混凝土多轴应力状态统计损伤本构模型应力-应变曲线

基于统计损伤理论的硫酸盐侵蚀混凝土本构模型研究

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工程力学 2019年第2期36卷 66-77页

作者：白卫峰刘霖艾管俊峰姚贤华华北水利水电大学水利学院河南郑州450046 华北水利水电大学土木与交通学院河南郑州450046

基于统计损伤理论及宏观试验现象,该文建立了考虑硫酸盐侵蚀影响的混凝土单轴、双轴压缩统计损伤本构模型。混凝土变形破坏被理解为细观断裂、屈服两种损伤模式的连续累积演化过程。硫酸盐侵蚀效应改变了混凝土微结构的组成成分和力学特... 详细信息

基于统计损伤理论及宏观试验现象,该文建立了考虑硫酸盐侵蚀影响的混凝土单轴、双轴压缩统计损伤本构模型。混凝土变形破坏被理解为细观断裂、屈服两种损伤模式的连续累积演化过程。硫酸盐侵蚀效应改变了混凝土微结构的组成成分和力学特征,进而改变了微裂纹萌生、扩展的形态以及损伤的累积演化过程,可通过改变断裂和屈服两种细观损伤机制演化过程的概率分布形态来模拟。分析结果表明:在硫酸盐侵蚀环境下,侵蚀程度的加深显著改变了混凝土细观损伤累积演化过程,最终导致混凝土宏观力学性能呈现先"强化"后"弱化"的现象。在此过程中,细观损伤演化过程呈现出明显地规律性,可由统计损伤模型中5个特征参数的变化规律表征。该文模型为复杂环境下侵蚀混凝土细观损伤过程预测和分析提供了新的方法和工具。

关键词：混凝土单轴压缩损伤机制本构模型硫酸盐侵蚀

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混凝土双轴压-压细观统计损伤本构模型

四川大学学报（工程科学版） 2013年第6期45卷 74-81页

作者：白卫峰管俊峰崔莹陈健云华北水利水电大学水利学院河南郑州450011 黄河勘测规划设计有限公司河南郑州450003 大连理工大学建设工程学院辽宁大连116024

细观损伤机制对混凝土材料宏观力学性能产生重要的影响。基于细观统计损伤理论及宏观试验现象,建立了混凝土双轴压-压细观统计损伤本构模型。考虑断裂、屈服2种细观损伤因素,损伤演化过程由主方向的压应变驱动;引入等效传递拉损伤应变... 详细信息

细观损伤机制对混凝土材料宏观力学性能产生重要的影响。基于细观统计损伤理论及宏观试验现象,建立了混凝土双轴压-压细观统计损伤本构模型。考虑断裂、屈服2种细观损伤因素,损伤演化过程由主方向的压应变驱动;引入等效传递拉损伤应变的概念,受压方向的压损伤由侧向拉损伤应变控制。采用该模型对双轴压-压应变比例加载路径下应力-应变曲线形成的包络面进行了预测,提取出双轴压-压强度包络线;从双轴强度、变形特性、包络面形状等角度对材料的双轴压缩损伤机制进行探讨。结果表明:该模型能够有效模拟双轴压-压加载情况下混凝土材料宏观力学行为,能够揭示细观损伤演化机制;细观屈服损伤模式在材料变形破坏过程中起到决定性作用,将整个变形过程分为统计均匀损伤及局部破坏2个阶段;区分峰值应力状态和局部破坏的临界状态,建议后者作为本构模型的最终破坏点。

关键词：混凝土双轴压缩细观统计损伤本构模型应力-应变曲线