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我国芒果布局时空变迁及对劳动力市场的反应研究 被引量:11
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作者 叶露 李玉萍 +2 位作者 李茂芬 梁伟红 刘恩平 《西南农业学报》 CSCD 北大核心 2021年第5期1054-1061,共8页
【目的】为我国芒果生产布局优化和生产要素合理配置提供参考依据。【方法】本研究运用GIS技术、重心分析法定量描述了1996-2018年我国芒果生产布局的时空演变,并利用2004-2018年我国芒果主产省区面板数据构建芒果种植面积对劳动力价格... 【目的】为我国芒果生产布局优化和生产要素合理配置提供参考依据。【方法】本研究运用GIS技术、重心分析法定量描述了1996-2018年我国芒果生产布局的时空演变,并利用2004-2018年我国芒果主产省区面板数据构建芒果种植面积对劳动力价格的供给反应模型,实证测算了芒果种植面积对劳动力价格及相关变量的反应程度。【结果】我国芒果生产重心逐渐向劳动力价格较低的西北地带迁移;劳动力价格上升对芒果生产布局变化的影响显著为负,在各主产省区劳动力价格差距较小的情况下,芒果生产集聚于自然禀赋较好的地带,当劳动力价格超出平均劳动力价格较多时,芒果生产则向劳动力价格较具优势的省区集聚。【结论】在劳动力约束不断强化的情形下,应积极培育易于机械收割的芒果新品种,研发省力化栽培模式,优化芒果生产布局及资源配置,进而实现降低成本和提高收益,减少劳动力价格上升带来的负面效应。 展开更多
关键词 芒果布局 时空变迁 劳动力价格 供给反应
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我国主要热带水果标准体系研究 被引量:1
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作者 邓春梅 李玉萍 +2 位作者 梁伟红 刘燕群 叶露 《湖南农业科学》 2022年第10期98-102,共5页
为了全面实现我国热带水果的标准化生产,增强我国主要热带水果在国内外市场的竞争力,系统梳理了我国主要热带水果产前、产中和产后相关标准数据。从标准的构成层次,标准的类别和标准发布年度及标龄3个方面对我国主要热带水果标准的概况... 为了全面实现我国热带水果的标准化生产,增强我国主要热带水果在国内外市场的竞争力,系统梳理了我国主要热带水果产前、产中和产后相关标准数据。从标准的构成层次,标准的类别和标准发布年度及标龄3个方面对我国主要热带水果标准的概况进行了综述;从部分国家标准更新缓慢、部分热带水果主产区的标准较少,部分热带水果标准体系结构不够合理和某些标准的制修订缺乏科学性且实施率低3个方面剖析了目前我国主要热带水果标准体系存在的问题;针对上述问题,从加快标准的修订与更新,进一步完善热带水果标准体系建设和加大标准宣传力度及配套服务3个方面提出了加快我国主要热带水果标准体系建设的建议。 展开更多
关键词 热带水果 标准体系 概况 存在问题 建议
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Isolation and Analysis of the Promoter of OsRacD from PhotoperiodSensitive Genic Male Sterile Rice 被引量:1
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作者 liang wei-hong WU Nai-hu 《Rice science》 SCIE 2006年第1期29-33,共5页
By using OsRacD cDNA as probe to screen the genomic library of photoperiod sensitive genic male sterile rice line Nongken 58S, a positive clone containing 2 kb promoter and 396 bp coding region of OsRacD was obtained.... By using OsRacD cDNA as probe to screen the genomic library of photoperiod sensitive genic male sterile rice line Nongken 58S, a positive clone containing 2 kb promoter and 396 bp coding region of OsRacD was obtained. Compared with the promoter of OsRacD cloned by reverse PCR from normal rice variety Nongken 58 (Nongken 58N), the homology was 99.8%, and the different nucleotides were outside the predicted response elements in promoter, suggesting that the fertility between rice varieties Nongken 58S and Nongken 58N under the long-day conditions was not attributed to the difference in the structure of OsRacD upstream regulation sequences, but to the developmental regulation of gene differential expression. 展开更多
关键词 photoperiod sensitive genic male sterility RICE genomic library OsRacD gene PROMOTER
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Expression Patterns of OsPIL11,a Phytochrome-Interacting Factor in Rice,and Preliminary Analysis of Its Roles in Light Signal Transduction 被引量:1
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作者 LI Li PENG Wei-feng +3 位作者 LIU Qian-qian ZHOU Jin-jun liang wei-hong XIE Xian-zhi 《Rice science》 SCIE 2012年第4期263-268,共6页
The expression patterns of OsPILll, one of six putative phytochrome-interacting factors, were analyzed in different organs of transgenic tobacco (Nicotiana tabacum). The expression of OsPIL 11 was organ-specific and... The expression patterns of OsPILll, one of six putative phytochrome-interacting factors, were analyzed in different organs of transgenic tobacco (Nicotiana tabacum). The expression of OsPIL 11 was organ-specific and was regulated by leaf development, abscisic acid (ABA), jasmonic acid (JA) and salicylic acid (SA). To further explore the role of OsPIL 11 in plant light signal transduction, a plant expression vector of OsPILll was constructed and introduced into tobacco. When grown under continuous red light, OsPILll-overexpressed transgenic tobacco exhibited shorter hypocotyls and larger cotyledons and leaves compared to wild-type seedlings. When grown under continuous far-red light, however, transgenic and wild-type seedlings showed similar phenotypes. These results indicate that OsPILll is involved in red light induced de-etiolation, but not in far-red light induced de-etiolation in transgenic tobacco, which lays the foundation for dissecting the function of OsPIL11 in phytochrome-mediated light signal transduction in rice. 展开更多
关键词 RICE phytochrome-interacting factor transgenic tobacco light signal transduction
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深基坑工程自动化监测技术研究 被引量:4
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作者 梁位鸿 《工程与建设》 2021年第6期1245-1247,共3页
基坑工程为高危大项目之一,由于深基坑工程受到地质、水文等外界环境影响较大,技术复杂及事故频发,因此在施工过程中应进行监测,确保施工环境及周边环境安全。基坑监测对象为支护结构、周围岩土体和周边环境,各监测对象具体监测内容根... 基坑工程为高危大项目之一,由于深基坑工程受到地质、水文等外界环境影响较大,技术复杂及事故频发,因此在施工过程中应进行监测,确保施工环境及周边环境安全。基坑监测对象为支护结构、周围岩土体和周边环境,各监测对象具体监测内容根据支护结构形式、岩土工程性状及周边环境情况而定。但是目前国内深基坑工程监测大多采用人工测量,耗费人力,且监测成果质量不高。与传统的人工监测相比,自动化监测技术能事项自动实时采集、传输、计算、报警等优势,并能向外延展,形成全方位的立体监测系统,确保施工过程顺利实施。文章从深基坑工程自动化监测技术的优势、监测对象和监测设备进行阐述,分析了全自动全站仪、3D激光扫描监测、水准仪和光纤传感监测技术,详细描述了监测基准点、监测点和设备的布设要点,为自动化监测技术的推广应用提供参考。 展开更多
关键词 深基坑工程 自动化监测 技术研究
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Re-study of Nucleon Pole Contribution in J/ψ → NN^-π Decay
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作者 ZONG Yuan-Yuan SHEN Peng-Nian +2 位作者 ZOU Bing-Song LIU Ji-Feng liang wei-hong 《Communications in Theoretical Physics》 SCIE CAS CSCD 2006年第3X期507-513,共7页
We re-study nucleon pole contribution in J/ψ → NN^-π decays by including the imaginary part for the propagator of the off-shell nucleon with energy above π N threshold. It is found that when including the imaginar... We re-study nucleon pole contribution in J/ψ → NN^-π decays by including the imaginary part for the propagator of the off-shell nucleon with energy above π N threshold. It is found that when including the imaginary part in the propagator, the branching ratio of the decay width will descend about 11% compared with the result without including the imaginary part, no matter whether including the off-shell form factors or not. It also leads to a phase of up to 25° for the off-shell nucleon propagator at invariant mass around 1400 MeV. This effect needs to be considered for detailed partial wave analysis of N^* resonances around this mass region. 展开更多
关键词 J/ψ decay form factor
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