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烤烟连作障碍调控措施研究进展

现代农业科技 2014年第8期 199-201页

作者：赵松辉蔡凯旋刘洪源石礼森陈继峰郑州大学生命科学学院河南郑州450001

烤烟连作障碍问题已经引起了多方关注,在众多研究成果的基础上,分析引起烤烟连作障碍的机理,主要在于土壤微生物种群、土壤营养成分、土壤酶活性和自毒作用,从合理的种植模式、科学合理的施肥方式等角度对烤烟连作障碍的作用进行了探讨... 详细信息

烤烟连作障碍问题已经引起了多方关注,在众多研究成果的基础上,分析引起烤烟连作障碍的机理,主要在于土壤微生物种群、土壤营养成分、土壤酶活性和自毒作用,从合理的种植模式、科学合理的施肥方式等角度对烤烟连作障碍的作用进行了探讨,旨在为需要烤烟连作的地区提供参考。

关键词：烤烟连作障碍种植模式合理施肥

河南烟草连作状况调查及连作障碍解决对策研究

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中国园艺文摘 2014年第5期30卷 218-222页

作者：陈继峰赵松辉蔡凯旋刘洪源石礼森郑州大学生命科学学院河南郑州450001

河南烤烟连作以4～5年为主。烤烟连作后病虫害加重,烟叶产量和品质下降等问题比较严重。目前研究认为烤烟连作障碍主要因为连作烟田矿质养分、微生物种类和数量、土壤中酶活性及自毒作用等方面发生了恶性变化,加重了烟草生产中病虫害发... 详细信息

河南烤烟连作以4～5年为主。烤烟连作后病虫害加重,烟叶产量和品质下降等问题比较严重。目前研究认为烤烟连作障碍主要因为连作烟田矿质养分、微生物种类和数量、土壤中酶活性及自毒作用等方面发生了恶性变化,加重了烟草生产中病虫害发生,阻碍了烟株的生长发育。文章通过对目前河南烟区连作情况的调查,并结合已有的研究,从连作烟田消毒、种植模式、施肥模式、微生物菌剂修复等方面探讨了缓解乃至解决烟草连作障碍问题的措施。

关键词：烟草连作障碍养分失衡酶活性微生物菌剂修复

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VSP微测井技术在四川盆地的应用效果分析

天然气勘探与开发 2004年第2期27卷 16-19页

作者：孙巧玲赵辉宋红玲中油西南油气田分公司四川石油管理局成都物探中心

VSP微测井是利用地震生产激发井开展表层结构调查研究工作 ,为逐点设计激发井深、提高激发子波的稳定性、精确求取静校正量提供准确的近地表速度、厚度模型。VSP微测井方法原理与常规井中激发微测井原理一样 ,都是利用直达波在地层中的... 详细信息

VSP微测井是利用地震生产激发井开展表层结构调查研究工作 ,为逐点设计激发井深、提高激发子波的稳定性、精确求取静校正量提供准确的近地表速度、厚度模型。VSP微测井方法原理与常规井中激发微测井原理一样 ,都是利用直达波在地层中的传播规律 ,通过改变检波器观测深度 ,获取不同的初至时间 ,根据深度换算成垂直 (t0 )时间 ,拟合时深曲线得到分层的速度和厚度。 2 0 0 3年度在GW地区 0 6测线的VSP微测井试验是VSP微测井技术在四川地区首次运用 ,其效果良好。本次表层结构调查 ,共实测 37口微测井 ,6 83个观测点 ,3415个观测数据 ,通过表层结构调查得到了沿 2 0 0 3KG0 6测线的近地表结构速度和厚度模型资料。 2 0 0 3KG0 6测线低速层速度在 35 0～ 4 89m/s ,厚度在 0 5～ 3 5m ;降速层速度在 5 37～ 15 75m/s ,多在 90 5～ 12 4 1m/s之间 ,厚度在 0 8～ 11 6m ;高速层速度在 1710～ 2 80 0m/s。最后 ,将采用表层模型约束的初至折射静校正方法的叠加剖面与不加表层模型约束的初至折射静校正方法的叠加剖面相对比 ,前者质量明显好于后者。因此 ,VSP微测井是一项有着广泛应用前景的表层结构调查技术。

关键词： VSP 微测井技术四川盆地地震勘探技术静校正激发点炮井距

基于SBM-DEA模型的江苏省碳排放效率研究

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国土与自然资源研究 2025年第1期 44-49页

作者：朱凡凡宋辉冯欢盐城工学院经济管理学院江苏盐城224051

本文运用MaxDEA9软件,基于非期望产出的SBM-DEA模型和Malmquist指数法从静态和动态两个方面研究2010-2021年江苏省及其13个地级市的碳排放效率。结果表明,(1)江苏省的整体碳排放效率在2010-2021年间稳步增长,并且在2019年开始达到有效,... 详细信息

本文运用MaxDEA9软件,基于非期望产出的SBM-DEA模型和Malmquist指数法从静态和动态两个方面研究2010-2021年江苏省及其13个地级市的碳排放效率。结果表明,(1)江苏省的整体碳排放效率在2010-2021年间稳步增长,并且在2019年开始达到有效,在空间上呈现苏北大于苏南大于苏中的不均匀分布格局。(2)江苏省碳排放效率的平均增长速度呈现苏北大于苏中大于苏南的趋势。(3)江苏省及其13个地级市技术变化指数变动对碳排放效率增长有关键作用,碳排放效率各期增长速度受到当期技术发展水平的制约。

关键词： “双碳”目标碳排放效率 SBM-DEA模型资源配置

Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： Tongyue Li Ziliang Xie Wenjiao Zhou Huan Tong Dawen Yang Anjia Zhang Yuan Wu Xiping song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)Materials Sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics

Novel Cr^(3+)-activated far-red emitting phosphors withβ-Ca_(3)(PO_(4))_(2)-type structure for indoor plant cultivation

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International Journal of Minerals,Metallurgy and Materials 2022年第6期29卷 1286-1294页

作者： Fangyi zhao Zhen song Quanlin Liu Beijing Municipal Key Laboratory of New Energy Materials and Technologies School of Materials Sciences and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Cr^(3+)-activated far-red and near-infrared phosphors have drawn considerable attention owing to their adjustable emission wavelengths and wide ***,we reported a series of Cr^(3+)-doped phosphors withβ-Ca_(3)(PO_(4))_(2)-type structure,of which Ca_(9)Ga(PO_(4))_(7):Cr^(3+) possessed the highest far-red emission *** an excitation of 440 nm,the Ca_(9)Ga(PO_(4))_(7):Cr^(3+) phosphors exhibited a broad emission band ranging from 650 to 850 nm and peaking at 735 nm,and the broadband superimposed two sharp lines centering at 690 and 698 *** optimal sample Ca_(9)Ga_(0.97)(PO_(4))_(7):0.03 Cr^(3+) had an internal quantum efficiency of 55.7%.The luminescence intensity of the Ca_(9)Ga_(0.97)(PO_(4))_(7):0.03 Cr^(3+) phosphor obtained at 423 K could maintain 68.5%of that at room temperature,demonstrating its outstanding luminescence thermal stability.A phosphor-conversion light-emitting diode was fabricated,indicating that the Ca_(9)Ga(PO_(4))_(7):Cr^(3+) phosphor has potential applications in indoor plant cultivation.

关键词： far-red near-infrared luminescence trivalent chromium ion plant cultivation

Energy Control of Plug-In Hybrid Electric Vehicles Using Model Predictive Control With Route Preview

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IEEE/CAA Journal of Automatica Sinica 2021年第12期8卷 1948-1955页

作者： Yang zhao Yanguang Cai Qiwen song Department of Mechanical and Electrical Engineering Guangdong University of Science and TechnologyDongguan 523083China School of Automation Guangdong University of TechnologyGuangzhou 510006China Transport Infrastructure Investment Company Guangzhou 510620China

The paper proposes an adoption of slope,elevation,speed and route distance preview to achieve optimal energymanagement of plug-in hybrid electric vehicles(PHEVs).Theapproach is to identify route features from historical and real-time traffic data,in which information fusion model and trafficprediction model are used to improve the information ***,dynamic programming combined with equivalent con-sumption minimization strategy is used to compute an optimalsolution for real-time energy *** solution is thereference for PHEV energy management control along the *** improve the system's ability of handling changing situation,the study further explores predictive control model in the real-time control of the energy.A simulation is performed to modelPHEV under above energy control strategy with route *** results show that the average fuel consumption of PHEValong the previewed route with model predictive control(MPC)strategy can be reduced compared with optimal strategy andbase control strategy.

关键词： Energy management model predictive control(MPC) optimal control plug-in hybrid electric vehicle(PHEV)

Pr-Tb synergistic strengthening on coercivity of Nd-Ce-Fe-B magnets grain boundary diffused with Pr-Tb-Al-Ga alloys

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Journal of Rare Earths 2024年第9期42卷 1704-1709,I0003页

作者： Ruifang song Hang zhao Haibo Feng Institute of Functional Materials Central Iron&Steel Research InstituteBeijing100081China

Sintered Nd-Ce-Fe-B magnets were grain boundary diffused(GBDed) with Pr_(x)Tb_(80-x)Al_(10)Ga_(10)(at%)(x=0,20,40,60,80) *** effect of Pr/Tb content in diffusion source on magnetic properties,microstructure and elements distribution of GBDed magnets was *** Pr is used to substitute for 75% Tb in diffusion source,Tb consumption per unit coercivity improvement of GBDed magnet reduces by 77%,compared with the Tb_(80)Al_(10)Ga_(10) diffused *** element diffuses into magnets and then forms Tb-rich shell with high magneto-crystalline anisotropy field surrounding main phase grains,resulting in substantial coercivity *** with low melting point diffuses deeply along liquid grain boundary phase during GBD *** can eliminate some sharp defects of main phase grains and make grain boundaries smooth,which provides diffusion channels for further diffusion of Tb ***,there are more diffusion channels for Tb and less Tb enriched at surface region,making Tb diffuse more deeply and improving Tb utilization *** method significantly improves the coercivity,and realizes the green,efficient and high-quality utilization of heavy rare earth(HRE)elements.

关键词： Grain boundary diffusion Rare earths Microstructure Synergistic strengthening

Changes of Accumulated Temperature, Growing Season and Precipitation in the North China Plain from 1961 to 2009

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Acta meteorologica Sinica 2011年第4期25卷 534-543页

作者： song Yanling zhao Yanxia WANG Chunyi National Climate Center China Meteorological Administration Beijing 100081 Chinese Academy of Meteorological Sciences China Meteorological Administration Beijing 100081 Hainan Provincial Meteorological Service Hainan 570203

Using the high-quality observed meteorological data, changes of the thermal conditions and precipitation over the North China Plain from 1961 to 2009 were examined. Trends of accumulated temperature and negative temperature, growing season duration, as well as seasonal and annual rainfalls at 48 stations were analyzed. The results show that the accumulated temperature increased significantly by 348.5℃ day due to global warming during 1961-2009 while the absolute accumulated negative temperature decreased apparently by 175.3℃ day. The start of growing season displayed a significant negative trend of -14.3 days during 1961- 2009, but the end of growing season delayed insignificantly by 6.7 days. As a result, the length of growing season increased by 21.0 days. The annual and autumn rainfalls decreased slightly while summer rainfall and summer rainy days decreased significantly. In contrast, spring rainfall increased slightly without significant trends. All the results indicate that the thermal conditions were improved to benefit the crop growth over the North China Plain during 1961-2009, and the decreasing annual and summer rainfalls had no direct negative impact on the crop growth. But the decreasing summer rainfall was likely to influence the water resources in North China, especially the underground water, reservoir water, as well as river runoff, which would have influenced the irrigation of agriculture.

关键词： North China Plain agriculture climate change