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Preliminary investigation and detection based on loop-mediated isothermal amplification(LAMP)of phytoplasmas associated with diseases in *** L.

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Oil Crop Science 2022年第4期7卷 219-224页

作者： yancheng wen Shufen Zhang Junping He Dongfang Cai Jiacheng Zhu Jianping Wang Jinhua Cao Kun Hu Lei Zhao Dongguo Wang Yizi Liu Institute of Industrial Crops of Henan Academy of Agricultural Sciences Zhengzhou450002China

In the last decade,some disease occurred on our experimental farms that had caused serious *** were not caused by fungi,bacteria or *** loop-mediated isothermal amplification(LAMP)technique,the detection results pointed to the possible pathogen as *** investigation results implied that phytoplasmas could cause more than 13 kinds of symptoms in almost all parts of plants in *** L.,including witches’broom,multi-stems,aggregate main inflorescences,and flat *** incidences of these phytoplasma-associated diseases in our experimental farms rose from 1.61%in 2010 to 6.00%in *** phytoplasma infected plants died without any growing *** studies would be helpful for detecting phytoplasmas diseases,selecting disease resistant germplasm and improving varieties with disease resistances in *** L.

关键词： B.napus L. Phytoplasma associated disease Pathogen Detection Loop-mediated isothermal amplification (LAMP)

Experimental study of population density using an optimized random forest model

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Journal of Geographical Sciences 2024年第8期34卷 1636-1656页

作者： LI Lingling LIU Jinsong LI Zhi wen Peizhang LI yancheng LIU Yi School of Geographical Sciences Hebei Normal UniversityShijiazhuang 050024China Hebei Technology Innovation Center for Remote Sensing Identification of Environmental Change Shijiazhuang 050024China Geocomputation and Planning Center of Hebei Normal University Shijiazhuang 050024China Hebei Key Laboratory of Environmental Change and Ecological Construction Shijiazhuang 050024China

Random forest model is the mainstream research method used to accurately describe the distribution law and impact mechanism of regional *** took Shijiazhuang as the research area,with comprehensive zoning based on endowments as the modeling unit,conducted stratified sampling on a hectare grid cell,and systematically carried out incremental selection experiments of population density impact factors,optimizing the population density random forest model throughout the process(zonal modeling,stratified sampling,factor selection,weighted output).The results are as follows:(1)Zonal modeling addresses the issue of confusion in population distribution laws caused by a single *** on a grid cell not only ensures the quality of training data by avoiding the modifiable areal unit problem(MAUP)but also attempts to mitigate the adverse effects of the ecological *** sampling ensures the stability of population density label values(target variable)in the training sample.(2)Zonal selection experiments on population density impact factors help identify suitable combinations of factors,leading to a significant improvement in the goodness of fit(R^(2))of the zonal models.(3)Weighted combination output of the population density prediction dataset substantially enhances the model's robustness.(4)The population density dataset exhibits multi-scale superposition *** a large scale,the population density in plains is higher than that in mountainous areas,while on a small scale,urban areas have higher density compared to rural *** optimization scheme for the population density random forest model that we propose offers a unified technical framework for uncovering local population distribution law and the impact mechanisms.

关键词： population density random forest model endowment zones stratified sampling factor selection weighted output

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变频调速在传统粗纱机改造中的应用

纺织科技进展 2004年第6期 49-51页

作者：靖文盐城纺织工业学校江苏盐城224000

介绍了欧姆龙PLC在传统粗纱机变速系统改造中的运用 ,阐述了变频调速在纺机改造中的作用。

关键词： PLC 变频调速粗纱机软件设计

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基于聚落的人口统计数据空间分解算法

地理科学 2024年第7期44卷 1196-1205页

作者：李艳成温佩璋刘劲松河北师范大学地理科学学院河北石家庄050024 河北省环境变化遥感识别技术创新中心河北石家庄050024 河北师范大学地理计算与规划研究中心河北石家庄050024 河北省环境演变与生态建设重点实验室河北石家庄050024

利用人口密度随机森林模型探讨人口密度与影响因子之间的非线性关系,是当前人口分布研究的前沿,但人口统计数据在空间分解过程中非正规约束下的最优输运问题尚未妥善解决。本文基于面积加权法,以矢量格式的村人口数据集为起点,以矢量格... 详细信息

利用人口密度随机森林模型探讨人口密度与影响因子之间的非线性关系,是当前人口分布研究的前沿,但人口统计数据在空间分解过程中非正规约束下的最优输运问题尚未妥善解决。本文基于面积加权法,以矢量格式的村人口数据集为起点,以矢量格式的聚落和公顷网格数据集为约束,设计了一套顾及聚落分布的人口统计数据空间分解算法。通过将村常住人口数据依次分解至聚落和公顷网格之中,获得了栅格人口密度数据集(SJZ_RK)。分析表明,SJZ_RK数据集的人口总数为1039.60万人,仅产生0.04%的误差,说明本文提出的人口统计数据空间分解算法具有较高准确度。经测算,SJZ_RK数据集的人口分布基尼系数(0.8909)>GHS_POP(0.8548)>SJZ_CUN_RK(0.5898)>GPWv4(0.5897),说明考虑聚落分布状况的SJZ_RK数据集很好地刻画了人口分布的空间集聚和异质性特征,为构建人口密度随机森林模型等监督类机器学习模型训练样本提供了高质量的人口密度标签数据。在刻画非聚落区、城市聚落区、值域范围方面,SJZ_RK数据集更接近实际情况,其在前两方面优于GHS_POP数据集,其在这3个方面均显著优于SJZ_CUN_RK和GPWv4两个数据集。本文算法破解了2个难题:①优化了获取高精度栅格人口密度数据集的计算程序,实现了相对准确的人口分布离散化表达;②统一了人口密度标签数据和影响因子数据的粒度,从而为人口密度随机森林模型训练样本摆脱MAUP的困扰,为克服人口密度随机森林模型的区群谬误问题,创造了必要条件。

关键词：人口密度面积加权分解算法聚落

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内外全景变形测量多镜面辅助数字图像相关方法

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实验力学 2024年第3期39卷 356-366页

作者：徐孟乔温清凤马衍成张伟玲代祥俊山东理工大学交通与车辆工程学院山东淄博255000

为实现管状结构内外全景变形的同时测量,本文发展了一种可变姿态多镜面辅助数字图像相关方法。测量系统由共轴成像系统和3个可变姿态光学反射镜及必要的冷光源组成,通过合理布置反射镜的位置并调整其姿态,使管道内外壁各部分同时成像于... 详细信息

为实现管状结构内外全景变形的同时测量,本文发展了一种可变姿态多镜面辅助数字图像相关方法。测量系统由共轴成像系统和3个可变姿态光学反射镜及必要的冷光源组成,通过合理布置反射镜的位置并调整其姿态,使管道内外壁各部分同时成像于相机靶;共轴采集系统的使用保证了2个相机均能够观测到所有待测区域;将采集到的图像进行相关计算并经过坐标转换后,可得到内外壁的全景形貌和三维变形分布。形貌和变形验证实验证明了该方法的准确性和有效性。

关键词：全景测量数字图像相关内外壁变形

Optimum Application Time and Application Rate of Nitrogen Fertilizer in Brassica napus L.

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Asian Agricultural Research 2018年第5期10卷 57-61页

作者： Junping HE Shufen ZHANG Jiacheng ZHU Jinhua CAO yancheng wen Dongfang CAI Lei ZHAO Dongguo WANG Jianping WANG Institute of Industrial Crops Henan Academy of Agricultural Sciences/Key Laboratory of Oil Crops in Huang-Huai-Hai PlainMinistry of Agriculture/Henan Provincial Key Laboratory for Oil Crops Improvement

To find proper nitrogen fertilizer application mode of rapeseed( Brassica napus L.),promote the high and stable yield of rapeseed,field experiment was carried out to study the effect of nitrogen fertilizer application modes on the yield and economic traits of Fengyou 10 rapeseed planted in two different fertility soils,and characteristics and differences of responses of different fertility soils to nitrogen fertilizer application modes were compared and analyzed. The results showed that the yield and related economic traits of rapeseed treated by nitrogen fertilizer were higher than the control group; in the nitrogen fertilizer treatment group,when the nitrogen fertilizer was applied as the base fertilizer and wintering fertilizer at the ratio of 7∶ 3,the rapeseed yield was higher than the control group and reached the highest; when the nitrogen fertilizer was applied as the base fertilizer,wintering fertilizer,and bud fertilizer at the ratio of 5∶ 3∶ 2,the rapeseed yield was significantly higher than the control group but was the lowest. These indicate that sufficient nitrogen supply is the basis for normal growth and development of rape seedlings. When the pure nitrogen fertilizer was at 192 kg/ha and the ratio of base fertilizer and wintering fertilizer was 7∶ 3,it can better coordinate the high yield of rapeseed and overall use of nitrogen fertilizer,and obtain higher rapeseed yield.

关键词： Brassica napus L. Nitrogen fertilizer application Yield Economic traits Soil fertility

Catalytic C-H activation-initiated transdiannulation:An oxygen transfer route to ring-fluorinated tricyclic γ-lactones

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Chinese Chemical Letters 2024年第9期35卷 145-149页

作者： Qiuyun Li Yannan Zhu Yining Wang Gang Qi wen-Juan Hao Kelu Yan Bo Jiang School of Chemistry and Chemical Engineering Yancheng Institute of TechnologyYancheng 224051China School of Chemistry&Materials Science Jiangsu Normal UniversityXuzhou 221116China Key Laboratory of Life-Organic Analysis of Shandong Province School of Chemistry and Chemical EngineeringQufu Normal UniversityQufu 273165China

Catalytic C–H activation-initiated annulation reactions have emerged as a versatile strategy for the efficient construction of diverse ring structural units and complex cyclic molecules in synthetic ***,we describe a new Rh(Ⅲ)-catalyzed C–H activation-initiated transdiannulation reaction of N,Ndimethyl enaminones with gem-difluorocyclopropenes in the presence of H_(2)O,enabling a facile and oxygen transfer access to ring-fluorinated tricyclicγ-lactones with a 6-5 ring-junction tetrasubstituted *** approach features bond-forming/annulation efficiency,good functional group tolerance and complete regioselectivity,which may include a complex process consisting of Rh(Ⅲ)-catalyzed C(sp2)–H activation,cyclic alkene insertion,defluorinated ring-opening of gem-difluorocyclopropane,intramolecular oxygen transfer,intramolecular cyclization and oxidative hydration.

关键词： C-H bond activation Enaminones Transannulation Oxygen transfer Regioselectivity

Beware of the serious harm of veterinary drug poisoning:a case report

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World Journal of Emergency Medicine 2024年第2期15卷 153-155页

作者： Ping Dai Jin Sun Tongyue Zhang Zhiqiang Zhou Zixi wen Tianzi Jian Aerbusili Genjiafu Baotian Kan Xiangdong Jian Department of Poisoning and Occupational Diseases Emergency MedicineQilu HospitalCheeloo College of MedicineShandong UniversityJinan 250012China Emergency Department Affiliated the Jianhu Clinical Medical College of Yangzhou UniversityYancheng 224700China Department of Occupational and Environmental Health School of Public HealthCheeloo College of MedicineShandong UniversityJinan 250012China School of Nursing and Rehabilitation Cheeloo College of MedicineShandong UniversityNursing Theory&Practice Innovation Research Center of Shandong UniversityJinan 250012China Department of Geriatric Medicine Qilu HospitalNursing Theory Innovation and Research Center of Shandong UniversityCheeloo College of MedicineShandong UniversityJinan 250012China

Veterinary drugs are substances(including pharmaceutical feed additives)used to prevent,treat,and diagnose diseases or regulate the physiological functions of *** drug poisoning in humans is relatively rare both in China and the rest of the ***,we report a case of death from veterinary drug poisoning from ***-closantel is a broad-spectrum antiparasitic drug,which has high efficacy against a variety of trematodes and nematodes.

关键词： drug drugs diseases

窄河道型致密砂岩储层特征及主控因素——以天府气田金华区块沙溪庙组为例

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断块油气田 2024年第1期31卷 1-10页

作者：何江杨羿陈文夏茂龙贾松何开来张迎春刘彦成西南石油大学地球科学与技术学院四川成都610500 中国石油西南油气田公司勘探开发研究院四川成都610041 中联煤层气有限责任公司北京100016

四川盆地天府气田金华区块沙溪庙组发育典型的窄河道型致密砂岩储层,具有低孔、低渗特征。基于详实的野外及岩心观察,结合薄片、扫描电镜及CT、核磁等分析测试,通过储层沉积微相、孔隙结构、成岩作用综合研究,阐明了储层发育主控因素。... 详细信息

四川盆地天府气田金华区块沙溪庙组发育典型的窄河道型致密砂岩储层,具有低孔、低渗特征。基于详实的野外及岩心观察,结合薄片、扫描电镜及CT、核磁等分析测试,通过储层沉积微相、孔隙结构、成岩作用综合研究,阐明了储层发育主控因素。研究表明:1)天府气田沙二段沉积相以泛滥平原陆上河流相为主,河道微相储层物性最佳,河道窄而细,常呈北东—南西向展布;2)储层岩石类型主要为岩屑长石砂岩,石英体积分数由下向上有明显增加趋势,孔隙类型以残余原生粒间孔为主,其次为粒内溶孔;3)孔隙结构表现为低孔喉、低分选、强非均质性特征,根据压汞参数,储层类型可细分为3类;4)影响储层的主要成岩作用为胶结和溶蚀,胶结作用具有破坏和保护双重影响,既可通过方解石胶结减孔,又可通过绿泥石环边胶结抑制压实,“富长石”背景下的长石溶蚀作用有效改善了储层。研究认为,天府气田金华区块优质的高能窄河道砂体、中浅埋藏残余的规模原生孔隙、叠加绿泥石环边抗压实及长石规模溶蚀作用改善储层,三者共同形成“窄河道非连续甜点”的成储模式。该典型模式的建立为天府气田的可持续开发提供了重要的理论支撑。

关键词：致密砂岩储层特征主控因素沙溪庙组天府气田