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套袋对桃果实成熟过程中酚酸类和类黄酮类物质积累的影响 被引量:28
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作者 周君 陈宗玲 +1 位作者 张琼 王红清 《园艺学报》 CAS CSCD 北大核心 2009年第12期1717-1724,共8页
以‘晚蜜’桃为试材,果实于盛花后75d套袋、盛花后144d除袋,以未套袋果作对照,应用HPLC-MS技术对果皮中酚酸类和类黄酮类物质进行了定性定量分析。在成熟果中分离、检测到了3种酚酸类物质,8种黄酮醇类物质,5种黄烷-3-醇类物质和2种花色... 以‘晚蜜’桃为试材,果实于盛花后75d套袋、盛花后144d除袋,以未套袋果作对照,应用HPLC-MS技术对果皮中酚酸类和类黄酮类物质进行了定性定量分析。在成熟果中分离、检测到了3种酚酸类物质,8种黄酮醇类物质,5种黄烷-3-醇类物质和2种花色苷类物质。伴随果实成熟,酚酸类和黄烷-3-醇类物质的含量逐渐下降;黄酮醇类物质在果实发育早期含量较高,而后逐渐降低,果实着色初期其含量骤然上升,到成熟后期又急剧下降;未套袋果在盛花后144d已有花色苷积累,套袋果除袋后果皮迅速合成花色苷。成熟期套袋果和未套袋果中的酚酸和黄烷-3-醇类物质的含量没有差异,但套袋果中花色苷类和黄酮醇类物质的含量显著高于未套袋果,其中套袋果的花色苷含量为未套袋果的1.74倍。试验表明,酚酸类和黄烷-3-醇类物质对光较敏感,套袋显著抑制了这两类物质的合成,但未影响成熟果中的含量,套袋处理增加了成熟果中花色苷和黄酮醇的积累。桃果皮中的花色苷类物质代谢在果实发育早期向花色苷以外的各分支代谢方向进行,果实着色初期同时积累黄酮醇和花色苷,到成熟后期主要为花色苷的合成。 展开更多
关键词 果实 套袋 HPLC-MS 花色苷 酚酸 黄酮醇 黄烷-3-醇 类黄酮
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套袋处理对肥城桃果实香气成分的影响 被引量:16
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作者 罗华 李敏 +1 位作者 宋红日 张连忠 《湖北农业科学》 北大核心 2012年第22期5072-5075,共4页
采用气相色谱-质谱联用技术研究套袋处理对肥城桃果实香气品质的影响。结果共检测到40种香气成分,且被分成6类,分别是酯类、内酯类、醇类、醛类、酮类和有机酸类。未套袋果实中检测出36种成分,套袋果实中检测出30种成分;其中(E)-2-己烯... 采用气相色谱-质谱联用技术研究套袋处理对肥城桃果实香气品质的影响。结果共检测到40种香气成分,且被分成6类,分别是酯类、内酯类、醇类、醛类、酮类和有机酸类。未套袋果实中检测出36种成分,套袋果实中检测出30种成分;其中(E)-2-己烯-1-醇、乙酸乙酯、苯甲醛、1-己醇、己醛、(Z)-3-己烯-1-醇等为肥城桃果实的特征性香气成分。C6醛类和C6醇类这些清香型化合物在套袋与不套袋处理果实中的相对含量分别占到了54.92%和53.00%;酯类和内酯类这些果香型化合物在套袋与不套袋处理果实中的相对含量分别为25.95%和26.60%。套袋处理之后的果实各类香气物质的相对含量与不套袋处理的果实差别不大,但香气成分种类减少,主要体现在果香型化合物上,这可能是导致肥城桃果实套袋后风味变淡的原因。 展开更多
关键词 肥城桃 套袋 香气成分
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套袋与不套袋富士苹果品质对比效果 被引量:10
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作者 韩玉侠 李智平 +2 位作者 常爱莉 王琦 屈李侠 《价值工程》 2015年第5期288-289,共2页
以不套袋富士苹果为对照,研究了套袋富士苹果与不套袋富士苹果的内外品质和经济效益。结果表明:套袋可促进苹果着色,增加果面光洁度、减少病虫侵害、果秀发病率和日烧率,提高商品售价,但降低了苹果的风味;内在品质相比较,套袋苹果单果... 以不套袋富士苹果为对照,研究了套袋富士苹果与不套袋富士苹果的内外品质和经济效益。结果表明:套袋可促进苹果着色,增加果面光洁度、减少病虫侵害、果秀发病率和日烧率,提高商品售价,但降低了苹果的风味;内在品质相比较,套袋苹果单果重量减轻8.8%,可溶性固形物含量降低5.4%,而硬度提高6.9%。 展开更多
关键词 富士苹果 套袋 不套袋 品质
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1-MCP处理对套袋红富士苹果贮藏期间抗氧化酶活性和丙二醛含量的影响 被引量:9
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作者 沈广宁 魏树伟 王少敏 《山东农业科学》 2011年第12期31-34,共4页
以红富士苹果为试材,研究了在0℃贮藏条件下,1μl/L 1-甲基环丙烯(1-MCP)处理套袋红富士苹果的抗氧化酶活性和丙二醛(MDA)含量的变化趋势。结果表明:1-MCP处理使红富士苹果的抗氧化酶活性峰值出现时间推迟,贮藏结束(120 d)时,MDA含量降... 以红富士苹果为试材,研究了在0℃贮藏条件下,1μl/L 1-甲基环丙烯(1-MCP)处理套袋红富士苹果的抗氧化酶活性和丙二醛(MDA)含量的变化趋势。结果表明:1-MCP处理使红富士苹果的抗氧化酶活性峰值出现时间推迟,贮藏结束(120 d)时,MDA含量降低。1-MCP处理套袋红富士苹果的抗氧化酶活性和MDA含量与未套袋果实变化趋势无明显差异,但贮藏结束时,套袋红富士果实的过氧化物酶(POD)、过氧化氢酶(CAT)活性及MDA含量低于未套袋果实,而超氧化物歧化酶(SOD)活性高于未套袋果实。1-MCP处理套袋红富士苹果的SOD活性高于未套袋果实14%,MDA含量是未套袋果实的64.5%。 展开更多
关键词 红富士 套袋 贮藏 1-MCP 抗氧化酶 MDA
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Effect of Metaxenia on Volatile Compounds in Bagged Apple Fruit of Fuji 被引量:8
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作者 王海波 王传增 +3 位作者 程来亮 常源升 何平 李林光 《Agricultural Science & Technology》 CAS 2017年第4期583-587,610,共6页
In the present study, the effect of pollen grain sources on volatile com- pounds in bagged apple fruit of Yan Fuji 3, grown at two experiment sites and pol- linated by pollens of other five cultivars was evaluated, to... In the present study, the effect of pollen grain sources on volatile com- pounds in bagged apple fruit of Yan Fuji 3, grown at two experiment sites and pol- linated by pollens of other five cultivars was evaluated, to select appropriate poll- enizer cultivars for Fuji, and to provide a theoretical basis for improving the flavor and aroma of bagged apple fruit of Fuji. The results proved the significant metaxe- nia effect of the five pollenizer cultivars on volatile compounds of bagged apple fruit of Fuji. The numbers of both volatile compounds and characteristic aroma com- pounds in bagged apple fruit pollinated by Golden Delicious were larger and those of the fruit pollinated by Gala were smaller at both experiment sites. However, there were differences in the numbers of volatile compounds and characteristic aroma compounds among the fruits pollinated by Starkrimson, Jinxiuhaitang and Ruby at both experimental sites. The differences were caused by 12 compounds that only existed at a low level in certain samples. All of them were not the aroma contribu- tors except ethyl 2-methylbutyrate. The content of alcohols in bagged Fuji fruit was largely increased by Starkrimson and Ruby pollination; the content of aldehydes was obviously increased by Golden Delicious, Starkrimson and Gala pollination; the con- tents of esters and terpenes were significantly increased by Golden Delicious, Starkrimson and Ruby pollination. Jinxiuhaitang pollination showed no significant ef- fects for improving the content of four categories of volatile compounds. The metax- enia of the pollenizer cultivars on volatile compounds in bagged Fuji fruit was stable at the two experimental sites. 展开更多
关键词 Metaxenia Fuji apple bagged fruits Volatile compounds
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4个矮化自根砧短枝富士品种套袋与不套袋果实品质比较分析 被引量:5
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作者 刘美英 赵明 +5 位作者 赵玲玲 唐岩 孙燕霞 刘大亮 张学勇 姜中武 《中国农学通报》 2020年第22期38-43,共6页
为研究双矮栽培模式下套袋、不套袋管理对短枝富士苹果品质的影响,以嫁接在M9T337矮化自根砧上的4个短枝富士品种为试材,检测不同栽培条件下的果实品质和香气物质成分。结果表明,套袋果实的可溶性固形物含量和总糖含量均低于不套袋果实... 为研究双矮栽培模式下套袋、不套袋管理对短枝富士苹果品质的影响,以嫁接在M9T337矮化自根砧上的4个短枝富士品种为试材,检测不同栽培条件下的果实品质和香气物质成分。结果表明,套袋果实的可溶性固形物含量和总糖含量均低于不套袋果实;苹果酸和琥珀酸是苹果中的主要酸组分,不同的短枝富士品种表现出不同的差异;4个短枝型富士品种的主要香气成分均为酯类,占总香气成分的77.71%~96.49%,是典型的酯香型苹果品种;‘烟富6’、‘沂源红’、‘宫崎短枝’3个品种,套袋和不套袋管理情况下主要香气成分均是乙酸己酯;‘龙富短枝’品种套袋果实的主要香气成分为乙酸己酯,而不套袋果实的主要香气成分为2-甲基丁酸己酯。 展开更多
关键词 短枝富士 双矮栽培 套袋 不套袋 糖酸组分 香气物质
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黄桃中4种农药残留动态与风险评估
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作者 刘玉红 金检生 +1 位作者 陈丽萍 孙彩霞 《浙江农业学报》 CSCD 北大核心 2024年第2期432-440,共9页
为探明4种未登记农药(腐霉利、氯虫苯甲酰胺、甲维盐和多效唑)在黄桃上的安全性和消解特性,在施药后套袋和施药后不套袋2种处理方法下,开展了这4种农药在黄桃中的消解动态与膳食风险评估研究。建立了液相色谱-串联质谱联用(LC-MS/MS)分... 为探明4种未登记农药(腐霉利、氯虫苯甲酰胺、甲维盐和多效唑)在黄桃上的安全性和消解特性,在施药后套袋和施药后不套袋2种处理方法下,开展了这4种农药在黄桃中的消解动态与膳食风险评估研究。建立了液相色谱-串联质谱联用(LC-MS/MS)分析方法同时测定黄桃中4种未登记农药残留量。结果表明,在0.05~5.0 mg·kg^(-1)(腐霉利、氯虫苯甲酰胺和多效唑)和0.001~0.05 mg·kg^(-1)(甲维盐)添加水平下,4种农药的平均回收率为75.6%~111.3%,相对标准偏差(RSD)为0.9%~5.2%。4种农药在黄桃中的降解均符合一级动力学方程。根据农药残留和风险评估结果,在推荐剂量下甲维盐和多效唑建议在黄桃上设置14 d的安全间隔期(PHI),氯虫苯甲酰胺建议设置3 d的PHI;腐霉利因降解比较缓慢,不建议在黄桃生产上使用。 展开更多
关键词 黄桃 套袋 未登记农药 残留动态 风险评估
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鼠标行为HHT变换的工业互联网用户身份认证 被引量:2
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作者 张一弓 易茜 +3 位作者 李剑 李聪波 尹爱军 易树平 《物联网学报》 2022年第2期77-87,共11页
工业互联网的快速发展引发了对网络安全的广泛关注,终端用户身份认证技术成为研究热点。根据工业互联网人机交互特点,设计了实验网站,收集了该网站24名用户两年半的非受控环境下鼠标行为数据作实例,采用希尔伯特黄变换(HHT,Hilbert-Huan... 工业互联网的快速发展引发了对网络安全的广泛关注,终端用户身份认证技术成为研究热点。根据工业互联网人机交互特点,设计了实验网站,收集了该网站24名用户两年半的非受控环境下鼠标行为数据作实例,采用希尔伯特黄变换(HHT,Hilbert-Huang transform)提取鼠标行为信号频域特征,结合时域特征,形成163维时频域联合特征矩阵,用于表征用户鼠标行为模式特征。使用Bagged tree、支持向量机(SVM,support vector machine)、Boost tree和K最邻近(KNN,K-nearest neighbor)算法构建网络用户身份认证模型,对比数据测试结果表明,Bagged tree算法在本案例中内部检测效果最佳,平均错误接受率(FAR,false acceptance rate)为0.12%、平均错误拒绝率(FRR,false rejection rate)为0.28%;外部检测中,平均FAR为1.47%。相较于传统鼠标动力学方法,使用HHT提取鼠标行为频域信息能更好地实现终端用户身份认证,为保障工业互联网安全提供有效的技术支撑。 展开更多
关键词 工业互联网 身份认证 鼠标行为 希尔伯特黄变换 bagged tree
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套袋对新红星苹果贮藏过程中香气物质的影响 被引量:3
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作者 王少敏 沈广宁 魏树伟 《山东农业大学学报(自然科学版)》 CSCD 北大核心 2009年第2期187-190,199,共5页
采用静态顶空(SHS)和气相色谱-质谱联用(GC-MS)技术,分析了新红星苹果0℃贮藏过程中香气成分的变化。结果表明(1)套双层袋新红星苹果采收时测定的香气有5类39种,套单层袋新红星苹果采收时测定的香气有4类46种,而不套袋新红星苹果的香气4... 采用静态顶空(SHS)和气相色谱-质谱联用(GC-MS)技术,分析了新红星苹果0℃贮藏过程中香气成分的变化。结果表明(1)套双层袋新红星苹果采收时测定的香气有5类39种,套单层袋新红星苹果采收时测定的香气有4类46种,而不套袋新红星苹果的香气4类51种;(2)0℃贮藏下随着时间的延长套袋和不套袋果实香气物质的相对百分含量均高于采收时,套袋果实以贮藏45 d时最高平均为99.16%,不套袋苹果香气物质的相对百分含量以贮藏90 d时最高为99.57%。(3)套袋果实香气物质种类呈先升后降趋势,对照果实香气物质种类呈先降后升趋势。(4)采收和贮藏前期套袋果实的特征香气相对百分含量没有比对照明显降低,贮藏90 d时套袋果实特征香气的相对百分含量显著低于对照。 展开更多
关键词 新红星 套袋 贮藏 香气 GC—MS
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套袋对富士苹果贮藏过程中香气物质的影响 被引量:5
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作者 王少敏 魏树伟 翟衡 《青岛农业大学学报(自然科学版)》 2009年第4期330-333,共4页
采用静态顶空(SHS)和气相色谱-质谱联用(GC-MS)技术,分析了富士苹果0℃贮藏过程中香气成分的变化。结果表明:①套袋导致富士苹果采收时香气物质相对百分含量降低。套双层袋富士苹果采收时香气物质相对百分含量平均为85.53%,而不套袋的... 采用静态顶空(SHS)和气相色谱-质谱联用(GC-MS)技术,分析了富士苹果0℃贮藏过程中香气成分的变化。结果表明:①套袋导致富士苹果采收时香气物质相对百分含量降低。套双层袋富士苹果采收时香气物质相对百分含量平均为85.53%,而不套袋的对照为92.19%;②0℃贮藏下随着时间的延长,套袋和不套袋富士苹果果实香气物质的相对百分含量均比采收时升高,但两种纸袋间差异不显著。贮藏60d时套袋果实香气物质的相对百分含量上升为94.79%,不套袋果实为98.02%,贮藏120d时套袋果实香气物质的相对百分含量上升为97.8%,不套袋的果实为98.05%;③0℃贮藏过程中套袋和不套袋果实香气物质的种类均呈先升高后降低的趋势;④采收和贮藏过程中,套袋果实的酯类、醇类物质相对百分含量明显低于对照。 展开更多
关键词 富士苹果 套袋 贮藏 香气 GC—MS
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Effect of Metaxenia on Sugars and Organic Acids and Taste Quality of Bagged Fuji Apple Fruits 被引量:2
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作者 Haibo WANG Chuanzeng WANG +3 位作者 Lailiang CHENG Yuansheng CHANG Ping HE Linguang LI 《Agricultural Biotechnology》 CAS 2017年第4期63-66,共4页
In order to provide reference for the selection of appropriate pollination varieties facilitating the improvement of the flavor quality of bagged Fuji apple, the metaxenia effects of 5 pollination varieties on sugars,... In order to provide reference for the selection of appropriate pollination varieties facilitating the improvement of the flavor quality of bagged Fuji apple, the metaxenia effects of 5 pollination varieties on sugars, organic acids and flavor quality of bagged Fuji fruit were studied. The results showed that the 5 pollination varieties had significant metaxenia effects on sugars, organic acids and flavor quality of bagged Fuji fruit. For the sugar components, the fruits pollinated with Golden Delicious and Jinxiuhaitang showed higher glucose contents, and the fruit pollinated with Gala had the highest sucrose content; the fruits pollinated by Gala, Golden Delicious and Ruby exhibited higher malic acids, and the oxalic acid content and the succinic acid content were higher in the fruits pollinated with Jinxiuhaitang and Ruby ; and the fruit pollinated with Gala had the highest total sugar content, and the total acid content was higher in the fruits pollinated by Jinxiuhaitang and Ruby. The sugar-acid ratio was higher in the fruits pollinated with Gala and Golden Delicious, and the lowest in the fruit pollinated with Ruby. The senso- ry evaluation of fruits showed that the fruit pollinated with Ruby tasted sour-sweet, while the fruits pollinated with other 4 pollination varieties were sour and sweet moderately. 展开更多
关键词 Metaxenia Fuji apple bagged fruits Sugars and organic acids flavor quality
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采前套袋栽培对“红香酥”梨果品质和鲜切保鲜效果的影响
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作者 韩春红 王倩 +3 位作者 张向展 李博 陈迪新 薛华柏 《北方园艺》 CAS 北大核心 2023年第2期80-87,共8页
以“红香酥”梨为试材,采用采前套袋栽培的方法,研究了采前套袋栽培方式对“红香酥”梨果实品质和鲜切保鲜效果的影响,以期为鲜切果蔬的保鲜研究提供参考依据。结果表明:套袋栽培的梨果实硬度和琥珀酸含量显著增加,可溶性糖、葡萄糖、... 以“红香酥”梨为试材,采用采前套袋栽培的方法,研究了采前套袋栽培方式对“红香酥”梨果实品质和鲜切保鲜效果的影响,以期为鲜切果蔬的保鲜研究提供参考依据。结果表明:套袋栽培的梨果实硬度和琥珀酸含量显著增加,可溶性糖、葡萄糖、果糖、山梨醇含量显著降低;随着贮藏时间的延长鲜切梨的失重率、褐变度、a*值、b*值不断上升,硬度不断下降,可溶性固形物和可溶性糖含量先上升后下降,多酚氧化酶(PPO)和过氧化物酶(POD)活性呈升-降-升的趋势;其中套袋栽培总体上加快了鲜切梨果实的失重率和褐变度、PPO活性、POD活性、总酚含量上升,还加快了果实可溶性固形物和可溶性糖含量的下降。未套袋栽培“红香酥”梨果实外观品质有所降低,但整体上能够提高其内在品质,并且有利于鲜切保鲜,“红香酥”梨鲜切保鲜选择未套袋栽培的梨果实更好。 展开更多
关键词 “红香酥”梨 套袋 鲜切 品质
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Forecasting the Demand of Short-Term Electric Power Load with Large-Scale LP-SVR 被引量:1
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作者 Pablo Rivas-Perea Juan Cota-Ruiz +3 位作者 David Garcia Chaparro Abel Quezada Carreón Francisco J. Enríquez Aguilera Jose-Gerardo Rosiles 《Smart Grid and Renewable Energy》 2013年第6期449-457,共9页
This research studies short-term electricity load prediction with a large-scalelinear programming support vector regression (LP-SVR) model. The LP-SVR is compared with other three non-linear regression models: Collob... This research studies short-term electricity load prediction with a large-scalelinear programming support vector regression (LP-SVR) model. The LP-SVR is compared with other three non-linear regression models: Collobert’s SVR, Feed-Forward Neural Networks (FFNN), and Bagged Regression Trees (BRT). The four models are trained to predict hourly day-ahead loads given temperature predictions, holiday information and historical loads. The models are trained on-hourly data from the New England Power Pool (NEPOOL) region from 2004 to 2007 and tested on out-of-sample data from 2008. Experimental results indicate that the proposed LP-SVR method gives the smallest error when compared against the other approaches. The LP-SVR shows a mean absolute percent error of 1.58% while the FFNN approach has a 1.61%. Similarly, the FFNN method shows a 330 MWh (Megawatts-hour) mean absolute error, whereas the LP-SVR approach gives a 238 MWh mean absolute error. This is a significant difference in terms of the extra power that would need to be produced if FFNN was used. The proposed LP-SVR model can be utilized for predicting power loads to a very low error, and it is comparable to FFNN and over-performs other state of the art methods such as: Bagged Regression Trees, and Large-Scale SVRs. 展开更多
关键词 Power Load Prediction Linear PROGRAMMING Support VECTOR Regression NEURAL Networks for Regression bagged Regression Trees
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不同果袋处理对红富士苹果贮藏生理的影响 被引量:2
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作者 魏树伟 王少敏 +2 位作者 陈锋 张静 翟衡 《中国农学通报》 CSCD 2007年第6期428-432,共5页
研究了套5种类型果袋对红富士苹果(Malus domestica cv.Red Fuji Spur)低温(0℃)贮藏品质的影响,部分果袋进行早套袋(6月10号)和晚套袋(6月23号)两个处理。各种套袋果实的呼吸速率和失水率在贮藏的第一个月内逐步提高达到峰值,其中套塑... 研究了套5种类型果袋对红富士苹果(Malus domestica cv.Red Fuji Spur)低温(0℃)贮藏品质的影响,部分果袋进行早套袋(6月10号)和晚套袋(6月23号)两个处理。各种套袋果实的呼吸速率和失水率在贮藏的第一个月内逐步提高达到峰值,其中套塑膜袋果实的呼吸速率比套小林袋的高47%,同时伴随着可滴定酸、可溶性糖以及硬度的持续降低;随后的一个月内呼吸受到明显抑制,各种品质指标下降缓慢,但在其后的贮藏时间里呼吸速率再次缓慢上升。套塑膜袋的果实仍具有较强的呼吸,晚套袋的果实比早套袋的呼吸略高。贮藏结束时(120d)套小林袋红富士的可滴定酸和果实硬度分别为0.2087%、9.43kg/cm^2,套塑膜袋的分别为0.1812%、8.12kg/cm2。综合贮藏过程中果实的呼吸、糖、酸、硬度等指标的变化结果可以看到,不同果袋以套塑膜袋的果实品质下降最大,套小林袋(KM-2)的果实品质下降最小,其次是双层内红袋、双层内黑袋,再次是双层内塑袋。 展开更多
关键词 红富士苹果 套袋 贮藏 品质
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The result of bagged Pyrinuron baits for controlrodent pest of forests
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作者 马力 邓刚 张蕊 《Journal of Forestry Research》 CAS CSCD 2000年第1期72-73,共2页
Bagged and dispersed Pyrinuron (a self-formulated rodenticide) were tested for control of Clethrionomus rutilus and Clethrionomus rufocanus in larch plantation, Pingshan area, Heilongjiang Province from Oct. 1998 to A... Bagged and dispersed Pyrinuron (a self-formulated rodenticide) were tested for control of Clethrionomus rutilus and Clethrionomus rufocanus in larch plantation, Pingshan area, Heilongjiang Province from Oct. 1998 to Apr. 1999. The results showed that the bagged Pyrinuron has good result for control of the two rodent pests. The density of rodents was reduced by 90.5% after application of bagged Pyrinuron. This application method has characteristics of long residual period, bait not going mould and saving labour force. 展开更多
关键词 bagged RODENTICIDE Pyrinuron LARCH PLANTATION RODENT pest CONTROL
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套袋和未套袋鸭梨果实中主要营养元素的周年变化动态研究 被引量:2
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作者 卢伟红 张玉星 《北方园艺》 CAS 北大核心 2012年第24期5-8,共4页
于2009~2010年在保定市河北农业大学梨园内,选取具有代表性的10a生鸭梨,测定鸭梨不同发育期未套袋果实、套袋果实中营养元素含量,研究套袋和未套袋鸭梨果实中主要营养元素含量变化规律,揭示其含量差异。结果表明:果实中10种营养元素含... 于2009~2010年在保定市河北农业大学梨园内,选取具有代表性的10a生鸭梨,测定鸭梨不同发育期未套袋果实、套袋果实中营养元素含量,研究套袋和未套袋鸭梨果实中主要营养元素含量变化规律,揭示其含量差异。结果表明:果实中10种营养元素含量随果实的膨大而逐渐减少,套袋和未套袋果实中N、P、K、Ca、Mg、Mn、Cu、Zn、B元素变化规律一致;套袋果实和未套袋果实中N、P、K、Mg、Mn、Cu元素含量基本相同,套袋果实中Fe、Zn元素总含量低于未套袋果实,Ca、B元素总含量高于未套袋梨果实。未套袋果实中各种常量元素总含量顺序为:K>N>P>Ca>Mg,微量元素总含量顺序为:Fe>B>Zn>Mn>Cu。 展开更多
关键词 鸭梨 果实 营养元素 套袋
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氯硝柳胺药砂袋缓释灭螺法江滩灭螺效果观察 被引量:2
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作者 严志春 吴耀伦 +3 位作者 胡建国 朱冬至 高林 方晴 《中国血吸虫病防治杂志》 CAS CSCD 1998年第6期333-335,共3页
用氯硝柳胺药砂袋在江滩进行缓释灭螺实验结果显示:2g/m2、4g/m2组与氯硝柳胺机喷2g/m2组,1996年施药后15d,活螺平均密度及活螺框出现率下降都在90%以上;1997年施药后90d,活螺平均密度下降90%以上,活螺框出现率下降80%以上... 用氯硝柳胺药砂袋在江滩进行缓释灭螺实验结果显示:2g/m2、4g/m2组与氯硝柳胺机喷2g/m2组,1996年施药后15d,活螺平均密度及活螺框出现率下降都在90%以上;1997年施药后90d,活螺平均密度下降90%以上,活螺框出现率下降80%以上。该法灭螺效果与降雨有关,且操作简便,省工、省力、省经费,适用于大面积高水源较远地段的江、河、湖滩的灭螺。 展开更多
关键词 氯硝柳胺 药砂袋 缓释灭螺 江滩地区 灭钉螺
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Seed and Wasp Production in the Mutualism of Figs and Fig Wasps 被引量:1
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作者 YaoJin-yan ZhaoNan-xian +3 位作者 ChenYi-zhu JiaXiao-cheng DengYuan YuHui 《Forestry Studies in China》 CAS 2005年第1期25-28,共4页
Figs (Moracea: Ficus) and fig wasps (Hymenoptera: Chlocloids: Agaonideae) depend on each other to complete their reproduction. Monoecious fig species and their pollinating wasps are in conflict over the use of fig ov... Figs (Moracea: Ficus) and fig wasps (Hymenoptera: Chlocloids: Agaonideae) depend on each other to complete their reproduction. Monoecious fig species and their pollinating wasps are in conflict over the use of fig ovaries which can either produce one seed or one wasp. From observation on Ficus virens Ait., we showed that female flowers with outer layer of ovaries (near to the wall of syconium) had no significant difference from that with inner and interval layer of ovaries (near to the syconium cavity), in which most seeds and wasps were produced. This meant that fig tree provided the same potential resource for seed and wasps production. Observation indicated that there was usually only one foundress in syconium at female flower phase and no com- petition pollinators. Measurement of the style length of female flowers and the ovipositor of pollinators indicated that most ovaries could be reached by pollinator’s ovipositor. However, at the male flower phase, production of seeds was significantly more than that of wasps including non-pollinating wasps but there was no significant difference between seed and pollinating wasp production when without non-pollinating wasps produced. This result indicated that non-pollinating wasps competed ovaries not with seeds but with pollinating wasps for ovipositing. Bagged experiment showed that the sampling fig species was not self-sterile which was important for figs and wasps to survive bad season. Seed production in self-pollinated figs was not significantly different from total wasps in- cluding non-pollinating ones. This might be related with the weaker competition among wasps since bagged figs were not easy to reach by wasps from outside. 展开更多
关键词 FICUS Ficus wasp mutualism conflicts seed and wasp production Seed and Wasp Production in the Mutualism of Figs and Fig Wasps Yao Jin-yan1 2 Zhao Nan-xian1 Chen Yi-zhu1* Jia Xiao-cheng1 2 Deng Yuan1 2 Yu Hui1 2 1South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 P. R. China 2Graduate School of the Chinese Academy of Sciences Beijing 100039 P. R. China ABSTRACT Figs (Moracea: Ficus) and fig wasps (Hymenoptera: Chlocloids: Agaonideae) depend on each other to complete their reproduction. Monoecious fig species and their pollinating wasps are in conflict over the use of fig ovaries which can either produce one seed or one wasp. From observation on Ficus virens Ait. we showed that female flowers with outer layer of ovaries (near to the wall of syconium) had no significant difference from that with inner and interval layer of ovaries (near to the syconium cavity) in which most seeds and wasps were produced. This meant that fig tree provided the same potential resource for seed and wasps production. Observation indicated that there was usually only one foundress in syconium at female flower phase and no com- petition pollinators. Measurement of the style length of female flowers and the ovipositor of pollinators indicated that most ovaries could be reached by pollinator’s ovipositor. However at the male flower phase production of seeds was significantly more than that of wasps including non-pollinating wasps but there was no significant difference between seed and pollinating wasp production when without non-pollinating wasps produced. This result indicated that non-pollinating wasps competed ovaries not with seeds but with pollinating wasps for ovipositing. bagged experiment showed that the sampling fig species was not self-sterile which was important for figs and wasps to survive bad season. Seed production in self-pollinated figs was not significantly different from total wasps in- cluding non-pollinating
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套袋梨果袋内与树冠的温湿度比较研究
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作者 褚凤杰 王广海 +1 位作者 王景涛 周志芳 《河北农业科学》 2006年第1期41-43,共3页
观测并分析了套袋鸭梨果实发育过程中及1d中的袋内与树冠内的温度和相对湿度变化。结果表明:袋内温度和相对湿度分别较树冠内平均高0.45℃和8.4%,温湿度系数高0.37;1d中袋内温湿度分别有16h和10~14h高于树冠内。
关键词 鸭梨 套袋 温度 湿度
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塑料粒料的包装及运输在中国的前景
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作者 ZEPPELIN Pnejmatic conveying Technology Company of Germany,Haifeng enterprise company of U. S. A 《硫磷设计与粉体工程》 2000年第2期18-23,共6页
德国ZEPPELIN公司的专家Wolfgang Krambrock对中国塑料粒料的包装运输现状作了分析。指出如仍大量甚至全部采用袋装运输方式是不合适的,应探讨采用散装运输方式的可行性。
关键词 塑料粒料 包装 运输 散装 中国 塑料厂
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