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Patterns of leaf N:P stoichiometry along climatic gradients in sandy region, north of China

Journal of Plant Ecology 2018年第2期11卷 218-225页

作者： Lifang Zhang lilong Wang Wenliang He Xinfang Zhang Lizhe An Shijian Xu MOE Key Laboratory of Cell Activities and Stress Adaptations School of Life SciencesLanzhou UniversityNo.222Southern Tianshui RoadLanzhou 730000China

Aims Biological and environmental factors determine geographic patterns of plant nutrient stoichiometry *** the distribution pattern and the potential drivers of nutrient stoichiometry is therefore critical for understanding the adaptive strategies and biogeochem-istry *** to determine how leaf nitrogen(N):phosphorus(P)stoichiometry is linked to biological and environmental factors,we investigated the patterns of psammophyte leaf N:P stoichiometry in sandy region,northern China,and the potential factors affecting leaf N:P stoichiometry were *** Based on 10 m×10 m quadrates survey,the leaves of 352 dominant psammophyte samples belonging to 167 species were collected cross a 3000 km east-west transect in sandy environments,north-ern *** samples were further classified into the following groups on the basis of plant life forms and functional groups(pho-tosynthesis pathways and nitrogen fixation).The structural equation modeling was employed to clarify the importance of biological and environmental factors on leaf N:P *** Findings Generally,the higher leaf N and P concentrations,but lower N:P ratio were found in psammophyte compared with other *** annual temperature(MAT)influenced the leaf N,P concentra-tions negatively,while mean annual precipitation(MAP)did *** played greater influence on leaf N,P concentrations than MAT *** affected leaf N,P concentrations directly or indirectly through phylogeny,while MAT only shown direct effect on leaf N *** psammophyte was more limited by N,rather P,in sandy region of northern *** results suggest that phylogeny of psammophyte and climate jointly influence leaf N:P stoichiometry,and the results could be helpful in modeling bio-geochemical nutrients cycling in vulnerable ecosystems like sandy environment.

关键词： N:P stoichiometry psammophyte climatic factors sandy region

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虚拟现实技术在森林防火培训系统的应用探索

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科技资讯 2024年第12期22卷 199-201页

作者：邱大佐范繁荣陈立龙刘友武福建三明林业学校福建三明365001 三明学院福建三明365004

研究介绍了将虚拟现实技术应用于森林防火培训的优势,分析了影响森林火灾的因素,详细介绍了虚拟现实技术在森林防火培训系统设计、实现和应用等方面的作用。旨在利用虚拟现实技术构建人机交互体系,实现沉浸式体验、漫游虚拟仿真展示、... 详细信息

研究介绍了将虚拟现实技术应用于森林防火培训的优势,分析了影响森林火灾的因素,详细介绍了虚拟现实技术在森林防火培训系统设计、实现和应用等方面的作用。旨在利用虚拟现实技术构建人机交互体系,实现沉浸式体验、漫游虚拟仿真展示、数据挖掘等系统功能,培养学生防灭火理论知识和实践技能,提升培训效果和应对能力,从而有助于提高学员的应对能力。

关键词：虚拟现实技术森林防火培训系统森林火灾安全教育

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甲基丙烯醛选择性氧化制甲基丙烯酸催化剂的研究进展

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河北科技大学学报 2024年第4期45卷 394-405页

作者：崇艳东张晨霖周理龙曹云丽张恒郑艳霞王硕河北科技大学化学与制药工程学院河北石家庄050018 平顶山学院化学与环境工程学院河南平顶山467000 曲阜师范大学化学与化工学院山东曲阜273165 山东理工大学化学化工学院山东淄博255000 扬州大学食品科学与工程学院江苏扬州225009

甲基丙烯酸甲酯(MMA)是一种重要的大宗化学品,用于生产有机玻璃、功能高分子材料、涂料等。基于石油化工和煤化工原料的C3/C4法被认为是生产MMA的绿色工艺,其中甲基丙烯醛(MAL)氧化为甲基丙烯酸(MAA)是该工艺的关键步骤。对催化该反应... 详细信息

甲基丙烯酸甲酯(MMA)是一种重要的大宗化学品,用于生产有机玻璃、功能高分子材料、涂料等。基于石油化工和煤化工原料的C3/C4法被认为是生产MMA的绿色工艺,其中甲基丙烯醛(MAL)氧化为甲基丙烯酸(MAA)是该工艺的关键步骤。对催化该反应所使用的催化剂进行了总结和分析,介绍了目前工业上所用的以Keggin结构磷钼钒酸盐为基础的催化剂,对催化剂的活性物种、不同组分的作用、负载型催化剂目前存在的问题进行了总结并提出了相应的解决方案,介绍了可催化该反应的非金属碳催化剂的研究进展。对于非金属碳催化剂,指出未来应从2个方面展开研究:1)设计制备高活性和稳定性的碳催化剂;2)利用表征手段构建催化剂的结构模型,探究碳催化机理。

关键词：催化剂工程甲基丙烯醛选择性氧化甲基丙烯酸杂多酸非金属催化剂

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Differential efficiency of a begomovirus to cross the midgut of different species of whiteflies results in variation of virus transmission by the vectors

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Science China(Life Sciences) 2018年第10期61卷 1254-1265页

作者： lilong Pan Qunfang Chen Tao Guo Xinru Wang Ping Li Xiaowei Wang Shusheng Liu Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects Institute of Insect Sciences Zhejiang University

Begomoviruses are important crop viral disease agents, and they are transmitted by whiteflies of the Bemisia tabaci *** the transmission of begomoviruses by whiteflies has been studied for many years, the mechanisms governing differential transmission of begomoviruses by different species of the Bemisia tabaci complex remain largely unknown. Here we firstly compared the transmission efficiency of tobacco curly shoot virus(TbCSV) by four species of the B. tabaci complex and found that Asia II 1 transmitted this virus with the highest efficiency, whereas MEAM1 transmitted it with the lowest. Next, by performing quantitative analysis of virus and immune-fluorescence detection, we found that the efficiency of TbCSV to cross the midgut wall was higher in Asia II 1 than in MEAM1. Finally, we set the quantities of virions in the haemolymph to the same level in Asia II 1 and MEAM1 via injection and then compared their capacity in TbCSV transmission, and found that the difference in TbCSV transmission between them became smaller. Taken together, our findings suggest that the efficiency of a begomovirus to cross the midgut wall of a whitefly to reach the vector's haemolymph plays a significant role in determining transmission of the virus.

关键词： begomovirus Bemisia tabaci differential transmission midgut

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Process Modeling and Control Simulation for a 500W@4.5K Helium Refrigerator

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Journal of Harbin Institute of Technology(New Series) 2016年第4期23卷 15-21页

作者： Xiaofei Lu Zhiwei Zhou Ming Zhuang lilong Qiu Institute of Plasma Physics Chinese Academy of Sciences

In order to investigate dynamic behaviors of a 500W@ 4.5K helium refrigerator,the process simulator has been completed. The cryogenic process model is described and main components are customized. The realtime communication between the process model and the control system has been achieved. Compared with the preliminary experimental data,the errors of temperatures during the process of 300 K-80 K are less than 10%.The process model is validated to predict the cool-down process very well. The controller parameters are tuned in simulation and applied to the actual refrigerator suitably. Based on the dynamic simulation,the operation of Joule-Thomson( JT) by pass valve has been optimized. And the cool- down process from 300 K to 4. 5 K has been simulated under the control programs. Simulation results indicate that this dynamic simulator based on actual control architecture is available to process control and operation optimization for the helium refrigerators.

关键词： Helium refrigerator process simulation controller tuning operation optimization virtual commissioning

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Hydrogen production from ammonia decomposition over Ni/CeO_(2) catalyst:Effect of CeO_(2) morphology

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Journal of Rare Earths 2023年第7期41卷 1014-1021,I0002页

作者： Chongqi Chen Xiaoshuang Fan Chen Zhou Li Lin Yu Luo Chaktong Au Guohui Cai Xiuyun Wang lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou UniversityFuzhou 350002China

Ammonia(NH_(3)) decomposition to release CO_x-free hydrogen(H_(2)) over non-noble catalysts has gained increasing *** this study,three nanostructured CeO_(2) with different morphologies,***(R).sphere(Sph),and spindle(Spi),were fabricated and served as supports for Ni/CeO_(2) *** CeO_(2)supports are different in particle sizes,specific surface area and porosity,resulting in the formation of Ni nanoparticles with distinguished sizes and *** surface properties of the Ni/CeO_(2) catalysts are not only distinct but also influential,affecting the adsorption and desorption of NH_(3),N_(2),and/or H_(2)*** Ni/CeO_(2)-R catalyst shows superior catalytic activity compared to the other two,owing to its smaller Ni crystallite size and larger BET surface *** most abundant strong basic sites are observed for Ni/CeO_(2)-Spi catalyst based on its exposed CeO_(2)(110) planes,which facilitates the donation of electrons to the Ni particles,benefiting the associative desorption of N ***,Ni/CeO_(2)-Spi shows higher catalytic activity than Ni/CeO_(2)-Sph,despite their almost identical Ni crystallite sizes.

关键词： NH_(3)decomposition Hydrogen production Ni/CeO_(2) Morphology Electron donation Rare earths

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The Study of Root Subspace Decomposition between Characteristic Polynomials and Minimum Polynomial

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Open Journal of Applied Sciences（应用科学） 2024年第7期 1637页

作者： lilong Kang Yu Wang Yingling Liu

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Effects of cerium and tungsten addition on acid-base properties of spindle-likeα-Fe_(2)O_(3)in low-temperature SCR of NO_(x)with NH_(3)

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Journal of Rare Earths 2022年第11期40卷 1734-1742,I0003页

作者： Jun Ni Xuanbei Peng Linlin Yang Kai Zhang Yangyu Zhang Yanliang Zhou Xiuyun Wang Chak-tong Au lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou UniversityFuzhou 350002China

Low-temperature selective catalytic reduction(SCR)is important for the elimination of NOfrom stationary *** the present study,the loading of Ce and W onα-Fe_(2)O_(3)was achieved through the integration of single-mode microwave and incipient wetness impregnation(IWI)*** scanning electron microscopy(SEM)and transmission electron microscopy(TEM)images reveal that the structure ofα-Fe_(2)O_(3)is spindle-like,and the structure remains unchanged after the introduction of Ce and/or *** results of NH-SCR investigation demonstrate that NOconversion over Ce-W/α-Fe_(2)O_(3)is more than85%at 300℃,which is much higher than that over Ce/a-Fe_(2)O_(3)andα-Fe_(2)O_(3),Our studies illustrate that the addition of Ce can significantly increase the amount of surface oxygen vacancies as well as sites of moderate *** the other hand,the addition of W can obviously decrease the amount of basic sites and increase the number of Br?nsted acid *** synergistic effect of Ce and W addition on balancing acidity/basicity properties accounts for the high activity of CeW/α-Fe_(2)O_(3)for NOremoval at low *** study provides insight into the relationship between acidity/basicity properties and catalytic performance of Ce-W/α-Fe_(2)O_(3)catalysts,which is beneficial to the design of high-performance NH-SCR catalyst for NOremoval at low temperatures.

关键词： NH_(3)-SCR Fe_(2)O_(3) NO_(x)removal Acidity/basicity properties Morphology structure Rare earths

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斑蝥黄对循环高温环境中怀乡鸡产蛋性能、生殖激素水平、卵泡发育的影响

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江苏农业学报 2024年第5期40卷 890-904页

作者：赵君文赵壮志谢婷婷孙卓钟佩珊效梅张丽吴江安立龙广东海洋大学滨海农业学院广东湛江524088

高温引起的鸡热应激会导致其生殖机能严重下降。本试验以26周龄雌性怀乡鸡为研究对象,探究斑蝥黄对循环高温环境中怀乡鸡产蛋性能、生殖激素水平、卵泡发育的影响。结果表明,与常温对照相比,循环高温环境中怀乡鸡产蛋率及血清中促卵泡素... 详细信息

高温引起的鸡热应激会导致其生殖机能严重下降。本试验以26周龄雌性怀乡鸡为研究对象,探究斑蝥黄对循环高温环境中怀乡鸡产蛋性能、生殖激素水平、卵泡发育的影响。结果表明,与常温对照相比,循环高温环境中怀乡鸡产蛋率及血清中促卵泡素(FSH)、黄体生成素(LH)、孕酮(P_(4))、雌二醇(E_(2))水平降低,等级卵泡、小黄卵泡、大黄卵泡、小白卵泡、大白卵泡数量降低,卵泡膜结构松散、断裂,卵泡颗粒细胞结构受损。常温环境中,饲粮中添加斑蝥黄对怀乡鸡产蛋性能、血清中生殖激素水平有一定提升作用,但对卵泡膜结构无明显影响。循环高温环境中,饲粮中添加斑蝥黄能够显著改善怀乡鸡产蛋性能,提高血清中生殖激素水平,提高各级卵泡数量,缓解高温造成的卵泡膜松散、断裂和卵泡颗粒细胞损伤。综上,斑蝥黄具有较强的抗氧化特性,能够提高怀乡鸡产蛋性能,调节血清中生殖激素水平,降低高温对怀乡鸡造成的伤害,使各级卵泡正常发育并排出。

关键词：斑蝥黄怀乡鸡循环高温卵泡发育产蛋率

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Target-oriented confinement of Ru-Co nanoparticles inside N-doped carbon spheres via a benzoic acid guided process for high-efficient low-temperature ammonia synthesis

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Journal of Energy Chemistry 2021年第6期30卷 140-146,I0005页

作者： Jun Ni Zhenni Tan Qianjin Sai Jie Zhu Xiuyun Wang Bingyu Lin Jianxin Lin Chak-tong Au lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou UniversityFuzhou 350002FujianChina

Ru-based heterogeneous catalysts have been used in a wide range of important ***,due to the sintering of Ru nanoparticles their practical applications are somewhat ***,for the first time we report a new and facile strategy to confine Ru and/or Co nanoparticles(NPs) in the channels of N-doped carbon using benzoic acid to guide the deposition location of *** developed catalyst with confined RuCo alloy particles exhibits high resistance against Ru sintering and displays excellent activity and long term stability for NH3 synthesis,achieving an NH3 synthesis rate of up to 18.9 mmol NH_(3) gcat^(-1)h^(-1)at 400℃,which is ca.2.25 times that of the catalyst prepared without confinement(with metal deposited on the support surface).In the latter case,there is an increase of nanoparticle size from 2.52 to 4.25 nm together with ca.48% decrease of NH_(3) synthesis rate after 68 h at 400℃.This study provides a new avenue for simple fabrication of precious-metal-based catalysts that are highly resistant against sintering,specifically suitable for low-temperature synthesis of ammonia with outstanding efficiency.

关键词： Ru-and Co-based catalysts Ammonia synthesis Confinement Sintering resistance Nanoparticle size

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