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促进烟草根系早生快发的移栽基质优化研究

植物营养与肥料学报 2024年第3期30卷 615-626页

作者：艾栋张云贵李志宏冯文强朱经伟陈曦常乃杰边立丽刘青丽中国农业科学院农业资源与农业区划研究所北京100081 中国烟草总公司四川省公司四川成都610041 贵州省烟草科学研究院贵州贵阳550081

[目的]针对烤烟移栽苗根系前期发育迟缓等问题,研究利用廉价有机材料和腐殖酸改良幼苗移栽基质对烤烟根区水肥环境和烟苗生长的影响,为研制高效和环境友好型烟草幼苗移栽载体奠定基础。[方法]常规移栽基质一般由秸秆、椰糠、草炭以3∶1... 详细信息

[目的]针对烤烟移栽苗根系前期发育迟缓等问题,研究利用廉价有机材料和腐殖酸改良幼苗移栽基质对烤烟根区水肥环境和烟苗生长的影响,为研制高效和环境友好型烟草幼苗移栽载体奠定基础。[方法]常规移栽基质一般由秸秆、椰糠、草炭以3∶1∶1混合而成,本试验以此基质作基础处理(JYC);另设添加腐殖酸钾(JYCK)、蛭石(JYCZ)、腐殖酸钾和蛭石(JYCZK)处理,以供试土壤为空白对照(CK),当幼苗在移栽基质中生长10、30、50天时,测定土壤理化指标和烤烟生物量,在生长10与50天时,测定烟草根系形态指标。[结果]与CK处理相比,基质移栽在移栽后10天的烟草根生物量和根冠比分别增加了48.3%~62.1%和80.4%~114.4%,烟株根长度和根分支数分别提高了45.9%~128.9%和52.0%~174.3%;移栽后50天的土壤硝态氮和溶解性有机碳(DOC)含量分别提高了62.9%~147.2%和230.3%~399.8%。基于随机森林模型分析,发现移栽基质、土壤温度和溶解性有机碳含量、根长度和根尖数显著影响烤烟地上部生物量;通过相关性分析和结构方程模型分析,发现移栽基质通过改善根区环境,直接或间接影响烤烟根系形态和促进地上部生物量的积累。与CK相比,JYC、JYCK、JYCZ和JYCZK处理的土壤硝态氮含量分别提高了65.2%、147.2%、62.9%和80.0%。JYCZK处理的烤烟根长度比JYC和JYCK处理分别提高了45.0%和30.1%,根分支数分别增加了28.9%和40.8%。[结论]在基础基质中添加0.5%的腐殖酸钾和16.7%的蛭石(体积)能更有效地协调土壤氮素供应水平,优化烤烟根系形态。

关键词：移栽基质根区环境根系形态烤烟

生姜青枯病菌拮抗芽孢杆菌的筛选、鉴定及发酵条件优化

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南方农业学报 2024年第2期55卷 468-478页

作者：崔文艳张佳佳俞伶俐张贵云王文佳彭玲罗喜燕何朋杰贵州中医药大学贵州贵阳550025 贵州大学绿色农药与农业生物工程教育部重点实验室贵州贵阳550025

【目的】筛选出对生姜青枯病病原菌具有较好拮抗效果的芽孢杆菌,并优化其发酵条件,旨在为丰富生姜青枯病的生防芽孢杆菌菌种资源及生防制剂的进一步开发应用打下理论基础。【方法】以生姜根际土壤为研究对象,以生姜青枯病菌为靶标,通过... 详细信息

【目的】筛选出对生姜青枯病病原菌具有较好拮抗效果的芽孢杆菌,并优化其发酵条件,旨在为丰富生姜青枯病的生防芽孢杆菌菌种资源及生防制剂的进一步开发应用打下理论基础。【方法】以生姜根际土壤为研究对象,以生姜青枯病菌为靶标,通过稀释涂布法和抑菌圈法从中分离并筛选出能高效拮抗生姜青枯病菌的芽孢杆菌;通过形态学观察、生理生化测定和分子生物学鉴定,确定拮抗菌株的分类地位;采用牛津杯法测定拮抗菌株对生姜青枯病菌的抑菌活性,并结合单因素和正交试验对其发酵条件进行优化。【结果】从生姜根际土壤中分离出1株对生姜青枯病菌具有较强拮抗作用的菌株HC-5,其抑菌圈直径达0.71 cm。综合形态学特征、生理生化特性及分子鉴定结果,将菌株HC-5鉴定为贝莱斯芽孢杆菌(Bacillusvelezensis)。单因素和正交试验结果显示,菌株HC-5的最适发酵培养基组分为糯米粉5.0 g/L、酵母浸粉7.0 g/L、硫酸锌11.0 g/L,最适发酵条件为培养温度35℃、培养时间36 h、接种量1.0%、转速180 r/min、初始pH 5.5、装液量100 m L。优化后菌株HC-5无菌上清液对生姜青枯病菌的抑菌圈直径增大至3.03 cm,相比于LB和发酵培养基条件下分别增大76.2%和62.9%。【结论】菌株HC-5对生姜青枯病菌具有良好的拮抗效果,经发酵条件优化后其无菌上清液对生姜青枯病菌的抑菌活性显著增强。菌株HC-5具有开发成生姜青枯病生防菌剂的潜力。

关键词：生姜青枯病贝莱斯芽孢杆菌拮抗活性正交试验发酵条件

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遵义市植烟土壤肥力综合评价及空间分布

中国土壤与肥料 2024年第2期 1-9页

作者：王新修苟剑渝刘京彭友朱经伟张恒张云贵刘青丽陈曦王韦燕荆晓雯杨荣李琼香李志宏中国农业科学院农业资源与农业区划研究所北京100081 贵州省烟草公司遵义市公司贵州遵义563000 贵州省烟草科学研究院贵州贵阳550081

了解遵义市植烟土壤综合肥力状况,为烟草种植规划提供理论支持。在遵义市13个区(县)168个乡镇采集3772份植烟土壤样品进行化学性状测定,运用模糊数学法评估植烟土壤肥力状况,采用Kriging插值法绘制植烟土壤化学性状和综合肥力评价空间... 详细信息

了解遵义市植烟土壤综合肥力状况,为烟草种植规划提供理论支持。在遵义市13个区(县)168个乡镇采集3772份植烟土壤样品进行化学性状测定,运用模糊数学法评估植烟土壤肥力状况,采用Kriging插值法绘制植烟土壤化学性状和综合肥力评价空间分布图。结果表明:①遵义市植烟土壤酸碱度、有机质、碱解氮、有效磷、速效钾的含量相互间呈极显著相关关系;有机质、碱解氮含量达到高或较高水平,土壤有效磷、速效钾含量较高,保障了烤烟生长所需的主要营养;②植烟土壤各肥力指标具有明显的空间变异特征,有机质与碱解氮分布基本一致,呈现极大的关联性,有机质、碱解氮和有效磷为斑块状分布态势,土壤pH值和速效钾呈块状分布。其中钾含量较高的区域与土壤pH值较低区域基本一致;③遵义市植烟土壤肥力综合评价得分为0.73,变异系数为16.8%,Ⅰ~Ⅲ级合计占比超过93%,遵义市植烟土壤肥力状况较好,空间变异较小。综合来看,遵义市植烟土壤肥力能供给优质烟叶生产的需求,但部分地区仍需加强有机肥、氮肥的使用,针对不同区域的肥力差异进行改良。

关键词：土壤综合肥力评价模糊数学法土壤肥力空间分布烤烟遵义

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Numerical investigation and modeling of sweep effects on inlet flow field of axial compressor cascades

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Chinese Journal of Aeronautics 2024年第2期37卷 296-308页

作者： Jiancheng zhang Donghai JIN Xingmin gui School of Energy and Power Engineering Beihang UniversityBeijing 100191China Jiangxi Research Institue of Beihang University Nanchang 330096China

Swept blades are widely utilized in transonic compressors/fans and provide high load,high through-flow,high efficiency,and adequate stall ***,there is limited quantitative research on the mechanism of the effect of swept blades on the flow field,resulting in a lack of direct quantitative guidance for the design and analysis of swept blades in fans/*** better understand this mechanism,this study employs a reduced-dimensional force equilibrium method to analyze more than 1500 swept cascades *** verify that circumferential fluctuation terms are responsible for inducing radial migration in the inlet airflow field of the swept blade,resulting in variations in the incidence angle and consequently leading to changes in the characteristics of the swept ***,a combination of simple functions and machine learning is utilized to model the circumferential fluctuation terms and quantify the sweep *** prediction accuracy of the model is high,with coefficient of determination greater than 0.95 on the test *** the model is applied in a meridional flow analysis program,the calculation accuracy of the program for the incidence angle is improved by 0.4°and 0.6°at the design and off-design conditions respectively,compensating for the program’s original ***,the model can also provide quantitative guidance for the design of swept blades,thereby reducing the number of design iterations and improving design efficiency.

关键词： Turbomachinery Sweep aerodynamics Quasi-3D method Incidence angle Circumferential fluctuation Machine learning

Value Iteration-Based Cooperative Adaptive Optimal Control for Multi-Player Differential Games With Incomplete Information

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 690-697页

作者： yun zhang Lulu zhang yunze Cai the Department of Automation Shanghai Jiao Tong UniversityShanghai 200240 the Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai 200240China

This paper presents a novel cooperative value iteration(VI)-based adaptive dynamic programming method for multi-player differential game models with a convergence *** players are divided into two groups in the learning process and adapt their policies *** method removes the dependence of admissible initial policies,which is one of the main drawbacks of the PI-based ***,this algorithm enables the players to adapt their control policies without full knowledge of others’ system parameters or control *** efficacy of our method is illustrated by three examples.

关键词： Adaptive dynamic programming incomplete information multi-player differential game value iteration

Neighbor Sum Distinguishing Total Choosability of Planar Graphs with Maximum Degree at Least 10

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 211-224页

作者： Dong-han zhang You Lu Sheng-gui zhang Li zhang School of Mathematics and Statistics Northwestern Polytechnical UniversityXi’an710129China School of Mathematics and Computer Application Shangluo UniversityShangluo726000China

A neighbor sum distinguishing(NSD)total coloringφof G is a proper total coloring of G such thatΣz∈EG(u)U{u}φ(z)≠Σz∈EG(v)U{v}φ(z)for each edge uv∈E(G),where EG(u)is the set of edges incident with a vertex *** 2015,Pilśniak and Wozniak conjectured that every graph with maximum degreeΔhas an NSD total(Δ+3)-***,Yang et *** that the conjecture holds for planar graphs withΔ≥10,and Qu et *** that the list version of the conjecture also holds for planar graphs withΔ≥*** this paper,we improve their results and prove that the list version of the conjecture holds for planar graphs withΔ≥10.

关键词： planar graphs neighbor sum distinguishing total choosibility combinatorial nullstellensatz discharging method

Detecting secondary spin with extreme mass ratio inspirals in scalar-tensor theory

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Chinese Physics C 2024年第9期48卷 210-224页

作者： Hong Guo Chao zhang yunqi Liu Rui-Hong Yue yun-gui Gong Bin Wang Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China Escola de Engenharia de Lorena Universidade de São PauloLorenaSP 12602-810Brazil Shanghai Frontier Research Center for Gravitational Wave Detection Shanghai Jiao Tong UniversitySha nghai 200240 China 4 School of Aeronautics and AstronauticsShanghai Jiao Tong UniversityShanghai 200240China School of Physics Huazhong University of Science and TechnologyWuhan 430074China Department of Physics School of Physical Science and TechnologyNingbo UniversityNingbo 315211China

In this study,we investigate the detectability of the secondary spin in an extreme mass ratio inspiral(EMRI) system within a modified gravity model coupled with a scalar *** central black hole,which reduces to a Kerr one,is circularly spiralled by a scalar-charged spinning secondary body on the equatorial *** analysis reveals that the presence of the scalar field amplifies the secondary spin effect,allowing for a lower limit of the detectability and an improved resolution of the secondary spin when the scalar charge is sufficiently *** findings suggest that secondary spin detection is more feasible when the primary mass is not large,and TianQin is the optimal choice for detection.

关键词： Gravitational wave EMRI secondary spin scalar radiation

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福建龙岩烟区烤烟施肥关键参数研究

中国土壤与肥料 2024年第7期 123-128页

作者：荆晓雯曾文龙蒋鸿月钟小丽边立丽李志宏兰其骏张云贵吴树松蒋代兵郭学清刘青丽中国农业科学院农业资源与农业区划研究所北京100081 福建省烟草公司龙岩市公司福建龙岩364000 云南农业大学烟草学院云南昆明650201

为了研究福建省龙岩市烟区不同肥料用量下烤烟的肥料效应,确定适宜的肥料施用量,在福建省龙岩市,以当地主栽品种云烟87为材料,开展了氮肥6水平、磷钾肥2水平的肥料田间试验。研究了氮、磷、钾肥料配合施用对烤烟养分吸收量、相对产量及... 详细信息

为了研究福建省龙岩市烟区不同肥料用量下烤烟的肥料效应,确定适宜的肥料施用量,在福建省龙岩市,以当地主栽品种云烟87为材料,开展了氮肥6水平、磷钾肥2水平的肥料田间试验。研究了氮、磷、钾肥料配合施用对烤烟养分吸收量、相对产量及限制产量的养分因素、经济性状及肥料利用率的影响。结果表明:在烤烟生育期内,氮、磷、钾的养分积累量表现为钾>氮>磷,养分积累主要集中在旺长期。缺素会使龙岩烟区烤烟产量和经济性状降低,缺氮、缺磷、缺钾对烤烟产量和经济性状的影响大小表现为缺氮>缺磷>缺钾。不同施氮处理中,N3处理(N:135kg/hm^(2),P_(2)O_(5):105kg/hm^(2),K_(2)O:375kg/hm^(2))的各项指标最优,分别为产量2053.17kg/hm^(2)、上等烟比例79.64%、中上等烟比例95.64%、产值61850.36元/hm^(2)、均价30.12元/kg、氮肥利用率31.27%农学利用率11.28kg/kg、偏生产力15.21kg/kg。用肥料效应方程对施氮量和烟叶产量进行拟合,方程为y=511.488+1.3614x+0.116x^(2)-0.0004x^(3)(R^(2)=0.9812)。综合烟叶产量、肥料利用率和经济效益,龙岩地区推荐施氮量为135.0~177.2kg/hm^(2)。

关键词：烤烟氮磷钾推荐施肥肥料效应方程

Histological Study on the Polyovular Folliclular Development of Chinese Prematural Lubei White Goat

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Journal of Northeast Agricultural University(English Edition) 2005年第2期12卷 112-117页

作者： WANG Hai-long zhang gui-xue LIU yun-bo zhang Jin-you College of Animal Science and Technology Northeast Agricultural University Harbin Heilongjiang 150030 PRC

The present study was conducted to investigate the histological characteristics of Polyovular follicles in Chinese Lubei white female goats with age 2-5 months. The results suggested that the healthy antral follicles with twin-oocyte could be observed. There were many multi-oocyte phenomena in primordial and primary follicles with a proportion of nearly 75% in primordial follicles. Primordial follicle was in the outer of cortex in ovaries and most of them remained active. The nest of multi-nuclear primordial follicle was developing into primordial follicle with 1 to 3 nucle

关键词： goat ovary multi-oocyte follicle