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Research on the development of electric agricultural machinery technology based on patent information
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作者 LIU Qin HU Lianglong GAO Ya 《智能化农业装备学报(中英文)》 2025年第4期64-72,共9页
This study takes the patent information of China's electric agricultural machinery technology as the research object,and uses patent measurement analysis method and visual analysis tools to carry out statistical a... This study takes the patent information of China's electric agricultural machinery technology as the research object,and uses patent measurement analysis method and visual analysis tools to carry out statistical analysis and comparative research on the relevant patent information from the perspectives of annual patent applications,patent structure,technological key,main applicants,patent layout,technology lifecycle and so on.The research results show that China's electric agricultural machinery technology innovation is developing rapidly,and the patent categories are mainly utility model and invention patents,and the proportion of invention patents is lower than utility model patents.Universities are the most important innovation subjects in this field,and technology research and development focuses on IPC(international patent classification)subcategories such as A01C(seeding,fertilization),B60K(power,transmission),and A01D(harvesting.mowing).Jiangsu Province and Shandong Province rank the top 2 in the number of domestic patent applications,and the United States and Japan are the two countries with the most layout in China.At present,the growth of electric agricultural machinery technology is weak,but the new technology has strong features,there is no sign of maturity,and it does not have signs of technological aging and still has greater development potential.The results of the study can provide information reference for clarifying the status quo,characteristics and development trend of China's electric agricultural machinery technology innovation. 展开更多
关键词 China electric agricultural machinery technology development patent analysis technology lifecycle IPC
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Announcement of the 40th Topical Meeting of the International Society of Electrochemistry
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《电化学(中英文)》 北大核心 2025年第6期65-67,共3页
You are cordially invited to the 40th Topical Meeting of the International Society of Electrochemistry,which will be held from 15 to 17 August 2025 in Changchun,China.Changchun is a City of Science,Education,and Resor... You are cordially invited to the 40th Topical Meeting of the International Society of Electrochemistry,which will be held from 15 to 17 August 2025 in Changchun,China.Changchun is a City of Science,Education,and Resort with a population of more than 9 million. 展开更多
关键词 RESORT Topical Meeting Education China International society Electrochemistry SCIENCE Changchun
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Mechanical properties and damage evolution law of cemented-gangue-fly-ash backfill modified with different contents of recycled steel fibers
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作者 CHE Chi-yuan CAO Sheng-gen +5 位作者 ZHANG Yun LIU Yang ZHAO Chang-zheng DU Shu-yu LI Jiang SHAN Chang-hao 《Journal of Central South University》 2025年第7期2661-2678,共18页
The cemented-gangue-fly-ash backfill(CGFB)prepared from coal-based solid waste materials commonly exhibits high brittleness,leading to an increased susceptibility to cracking.Uniaxial compressive strength(UCS),acousti... The cemented-gangue-fly-ash backfill(CGFB)prepared from coal-based solid waste materials commonly exhibits high brittleness,leading to an increased susceptibility to cracking.Uniaxial compressive strength(UCS),acoustic emission(AE),and scanning electron microscopy tests were conducted on CGFB samples with recycled steel fiber(RSF)contents of 0,0.5%,1.0%and 1.5%to assess the mechanical properties and damage evolution law of the CGFB.The research findings indicate that:1)When RSF contents were 0.5%,1%,and 1.5%,respectively,compared to samples without RSF,the UCS decreased by 3.86%,6.76%,and 15.59%,while toughness increased by 69%,98%,and 123%;2)The addition of RSFs reduced the post-peak stress energy activity and increased the fluctuations in the b-value;3)As the RSF dosage increased from 0 to 1.5%,the per unit dissipated strain energy increased from 5.84 to 21.51,and the post-peak released energy increased from 15.07 to 33.76,indicating that the external energy required for the CGFB sample to fail increased;4)The hydration products,such as C-S-H gel,ettringite,and micro-particle materials,were embedded in the damaged areas of the RSFs,increasing the frictional force at the interface between the RSF and CGFB matrix.The shape variability of the RSFs caused interlocking between the RSFs and the matrix.Both mechanisms strengthened the bridging effect of the RSFs in the CGFB,thereby improving the damage resistance capability of CGFB.The excellent damage resistance occurred at an RSF content of 0.5%;thus,this content is recommended for engineering applications. 展开更多
关键词 recycled steel fibers cemented-gangue-fly-ash backfill acoustic emission crack development energy evolution
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DEVELOPMENT AND ERROR ANALYSIS OF AN INSPECTING SYSTEM FOR MEASURING THE ROTATIONAL INERTIA OF BULLETS 被引量:15
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作者 车英 李占国 +3 位作者 陈礼华 白素平 马宏 韩文波 《兵工学报》 EI CAS CSCD 北大核心 2000年第1期-,共3页
介绍了一种用于测量弹丸转动惯量的高精度测量仪器,该仪器利用双悬丝扭摆机构、光电计时系统提取摆动周期信息,由MCS-51系列单片机组成的测量系统进行数据处理,并由LED显示器测量结果。文中阐述了仪器的工作原理, 推导了所需的计算... 介绍了一种用于测量弹丸转动惯量的高精度测量仪器,该仪器利用双悬丝扭摆机构、光电计时系统提取摆动周期信息,由MCS-51系列单片机组成的测量系统进行数据处理,并由LED显示器测量结果。文中阐述了仪器的工作原理, 推导了所需的计算公式,分析了产生测量误差的因素,进行了定量精度分析,给出了实验结果与测量精度。 展开更多
关键词 转动惯量 摆动周期 测量误差 development aND ERROR aNaLYSIS of aN INSPECTING
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N^(6)-methyladenosine modification and skin diseases
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作者 JIANG Ling HU Yibo CHEN Jing 《中南大学学报(医学版)》 北大核心 2025年第3期382-395,共14页
Currently,research on N^(6)-methyladenine(m^(6)A)is extensive in the field of oncology,while studies involving m^(6)A and skin diseases remain relatively limited.Based on existing reports,we searched PubMed and Web of... Currently,research on N^(6)-methyladenine(m^(6)A)is extensive in the field of oncology,while studies involving m^(6)A and skin diseases remain relatively limited.Based on existing reports,we searched PubMed and Web of Science for literature related to m^(6)A and dermatological conditions.Analysis of citation counts and journal impact factors revealed a significant upward trend in the volume of m^(6)A-related research.Term frequency analysis of titles and abstracts indicated that studies mainly focus on skin tumors and inflammatory or immune-related skin diseases,particularly melanoma,psoriasis,and skin development.Transcriptomic data from the Gene Expression Omnibus(GEO)were analyzed,revealing differential expression of m^(6)A-related genes in 4 types of skin tumors(including squamous cell carcinoma and basal cell carcinoma)as well as in inflammatory skin diseases such as psoriasis and atopic dermatitis,and potential mechanisms of action were also explored.Findings suggest that m^(6)A modifications exhibit heterogeneity between neoplastic and nonneoplastic skin diseases.However,the regulatory mechanisms of m^(6)A dynamic modifications on key genes involved in dermatological disorders remain unclear and warrant further investigation. 展开更多
关键词 skin tumors inflammatory and immune-related skin diseases N^(6)-methyladenosine EPIGENETICS drug development
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CRISPR/Cas9介导的doublesex基因敲除导致草地贪夜蛾雄成虫翅发育畸形 被引量:1
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作者 张浩楠 顾俊文 +3 位作者 张昕达 魏巍 康秋阁 张琪 《昆虫学报》 北大核心 2025年第6期720-727,共8页
【目的】通过CRISPR/Cas9基因编辑技术对草地贪夜蛾Spodoptera frugiperda双性基因doublesex(Sfdsx)单靶点敲除,旨在探究Sfdsx对草地贪夜蛾雄成虫翅发育的影响。【方法】利用CRISPR/Cas9基因编辑技术对草地贪夜蛾胚胎Sfdsx雌雄共有区域... 【目的】通过CRISPR/Cas9基因编辑技术对草地贪夜蛾Spodoptera frugiperda双性基因doublesex(Sfdsx)单靶点敲除,旨在探究Sfdsx对草地贪夜蛾雄成虫翅发育的影响。【方法】利用CRISPR/Cas9基因编辑技术对草地贪夜蛾胚胎Sfdsx雌雄共有区域进行敲除,构建Sfdsx突变体;待化蛹后,在显微镜下观察草地贪夜蛾Sfdsx突变体蛹及成虫翅的形态特征差异。【结果】草地贪夜蛾Sfdsx突变体出现显著的性别比趋于雄性(雌∶雄=0∶14),位于腹部第8-9节的雄蛹生殖孔两侧发生严重扭曲;雄成虫突变体的翅性状趋向性别中间态,其中,前翅中央的肾形斑变形、翅末端黑斑消失、翅鳞片排列错乱。后翅翅展畸形,翅鳞片排列发生改变,着生小黑斑。【结论】CRISPR/Cas9介导的Sfdsx基因公共区域的敲除导致草地贪夜蛾雄成虫翅发育畸形。本研究的结果为利用昆虫不育技术(sterile insect technology,SIT)调控草地贪夜蛾的发育提供了理想的基因靶标和理论依据。 展开更多
关键词 草地贪夜蛾 基因敲除 CRISPR/Cas9 DOUBLESEX 翅发育
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辣椒SEP亚家族基因鉴定及CaSEP3表达分析
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作者 梁心仪 汤冰倩 +2 位作者 张新昊 邹学校 刘峰 《湖南农业大学学报(自然科学版)》 北大核心 2025年第4期15-24,共10页
利用ST-8樟树港辣椒全基因组鉴定得到6个SEPALLATA(SEP)亚家族蛋白编码基因,对其理化性质、染色体定位、编码蛋白保守基序和保守结构域进行分析;将辣椒SEP基因与拟南芥、番茄、水稻和玉米的SEP基因共同构建系统进化树;探究CaSEP3的组织... 利用ST-8樟树港辣椒全基因组鉴定得到6个SEPALLATA(SEP)亚家族蛋白编码基因,对其理化性质、染色体定位、编码蛋白保守基序和保守结构域进行分析;将辣椒SEP基因与拟南芥、番茄、水稻和玉米的SEP基因共同构建系统进化树;探究CaSEP3的组织表达水平及编码蛋白的亚细胞定位。结果表明:辣椒SEP基因分布于5条染色体上,编码蛋白都含有MADS结构域(MADS_MEF2_like)和K结构域(K-box);辣椒SEP基因可分为2类,即SEP3和SEP1/2/4,这与番茄和拟南芥SEP基因的进化树类似。辣椒CaSEP3是拟南芥AtSEP3的同源蛋白,定位于细胞核中,CaSEP3在花蕾、胎座和果皮中高表达,推测其参与辣椒花器官和肉质果实的发育。常见激素和非生物胁迫处理后(0~24h),脱落酸(ABA)、H_(2)O_(2)、NaCl可使CaSEP3表达量上调,其余处理下CaSEP3在叶片和根部的表达量变化不明显。 展开更多
关键词 辣椒 花发育 SEPaLLaTa亚家族 生物信息学 表达分析
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Comparative analysis of SIMILAR to RCD ONE(SRO)family from tetraploid cotton species and their diploid progenitors depict their significance in cotton growth and development
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作者 SHABAN Muhammad TABASSUM Riaz +5 位作者 RANA Iqrar Ahmad ATIF Rana Muhammad AZMAT Muhammad Abubakkar IQBAL Zubair MAJEED Sajid AZHAR Muhammad Tehseen 《Journal of Cotton Research》 CAS 2024年第1期45-57,共13页
Background SRO(Similar to RCD1)genes family is largely recognized for their importance in the growth,develop-ment,and in responding to environmental stresses.However,genome-wide identification and functional character... Background SRO(Similar to RCD1)genes family is largely recognized for their importance in the growth,develop-ment,and in responding to environmental stresses.However,genome-wide identification and functional characteri-zation of SRO genes from cotton species have not been reported so far.Results A total of 36 SRO genes were identified from four cotton species.Phylogenetic analysis divided these genes into three groups with distinct structure.Syntenic and chromosomal distribution analysis indicated uneven distribu-tion of GaSRO,GrSRO,GhSRO,and GbSRO genes on A2,D5 genomes,Gh-At,Gh-Dt,Gb-At,and Gb-Dt subgenomes,respectively.Gene duplication analysis revealed the presence of six duplicated gene pairs among GhSRO genes.In promoter analysis,several elements responsive to the growth,development and hormones were found in GhSRO genes,implying gene induction during cotton growth and development.Several miRNAs responsive to plant growth and abiotic stress were predicted to target 12 GhSRO genes.Organ-specific expression profiling demonstrated the roles of GhSRO genes in one or more tissues.In addition,specific expression pattern of some GhSRO genes dur-ing ovule development depicted their involvement in these developmental processes.Conclusion The data presented in this report laid a foundation for understanding the classification and functions of SRO genes in cotton. 展开更多
关键词 COTTON SRO MIRNas Gene duplications Gene expression Ovule development
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Morphological characteristics,developmental dynamics,and gene temporal expressions across various development stages of Aphis gossypii sexual female
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作者 LÜJingli WANG Liuyu +10 位作者 ZHANG Kaixin LI Dongyang GAO Mengxue GUO Lixiang TANG Zhijuan GAO Xueke ZHU Xiangzhen WANG Li JI Jichao LUO Junyu CUI Jinjie 《Journal of Cotton Research》 CAS 2024年第4期372-385,共14页
Background Aphis gossypii(Hemiptera:Aphididae)is a worldwide polyphagous phloem-feeding agricultural pest,and it can produce offspring by sexual or asexual reproduction.Compared with dozens of generations by parthenog... Background Aphis gossypii(Hemiptera:Aphididae)is a worldwide polyphagous phloem-feeding agricultural pest,and it can produce offspring by sexual or asexual reproduction.Compared with dozens of generations by parthenogenesis,sexual reproduction is performed in only one generation within one year,and little is known about the sexual reproduction of A.gossypii.In this study,sexual females of A.gossypii were successfully obtained through a previously established induction platform,and the morphological characteristics,developmental dynamics,and temporal gene expression were examined.Subsequently,signaling pathways potentially involved in regulating the growth,development,and reproduction of sexual females were investigated.Results The morphological observation showed that from the 1st instar nymph to adult,sexual females exhibited a gradually deepened body color,an enlarged body size,longer antennae with a blackened end,and obviously protruding cauda(in adulthood).The anatomy found that the ovaries of sexual females developed rapidly from the 2^(nd)instar nymph,and the embedded oocytes matured in adulthood.In addition,time-course transcriptome analysis revealed that gene expression profiles across the development of sexual females fell into 9 clusters with distinct patterns,in which gene expression levels in clusters 1,5,and 8 peaked at the 2^(nd)instar nymphal stage with the largest number of up-regulated genes,suggesting that the 2^(nd)instar nymph was an important ovary development period.Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analysis revealed that a large number of genes in the sexual female adult were enriched in the TGF-beta signaling pathway and Forkhead box O(FoxO)signaling pathway,highlighting their important role in sexual female adult development and reproduction.Conclusion The morphological changes of the sexual female at each developmental stage were revealed for the first time.In addition,time-course transcriptomic analyses suggest genes enriched in the TGF-beta signaling pathway and FoxO signaling pathway probably contribute to regulating the development and oocyte maturation of sexual females.Overall,these findings will facilitate the regulating mechanism research in the growth and development of sexual females by providing candidate genes. 展开更多
关键词 aphis gossypii Sexual female Growth and development OOGENESIS Time-course transcriptome
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An Effective 3D-CFD Methodology for the Complementary Virtual Development of Alternative Fuels and Engine Concepts
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作者 Robin SCHMELCHER Thomas GAL +6 位作者 Mario PIPOLO Cristian TORTORELLA Antonino VACCA Edoardo ROSSI Francesco CUPO Marco CHIODI AndréCASAL KULZER 《同济大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第S01期1-8,共8页
With the aim of reducing the cost of developing internal combustion engines,while at the same time investigating different geometries,layouts and fuels,3D-CFD-CHT simulations represent an indispensable part for the de... With the aim of reducing the cost of developing internal combustion engines,while at the same time investigating different geometries,layouts and fuels,3D-CFD-CHT simulations represent an indispensable part for the development of new technologies.These tools are increasingly used by manufacturers,as a screening process before building the first prototype.This paper presents an innovative methodology for virtual engine development.The 3D-CFD tool QuickSim,developed at FKFS,allows both a significant reduction in computation time and an extension of the simulated domain for complete engine systems.This is possible thanks to a combination of coarse meshes and self-developed internal combustion engine models,which simultaneously ensure high predictability.The present work demonstrates the capabilities of this innovative methodology for the design and optimization of different engines and fuels with the goal of achieving the highest possible combustion efficiencies and pollutant reductions.The analysis focuses on the influence of different fuels such as hydrogen,methanol,synthetic gasolines and methane on different engine geometries,in combination with suitable injection and ignition systems,including passive and active pre-chambers.Lean operations as well as knock reduction are discussed,particularly for methane and hydrogen injection.Finally,it is shown how depending on the chosen fuel,an appropriate ad-hoc engine layout can be designed to increase the indicated efficiency of the respective engines. 展开更多
关键词 eFuels METHaNE METHaNOL hydrogen CO_(2)reduction virtual development 3D-CFD
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Resource allocation optimization of equipment development task based on MOPSO algorithm 被引量:8
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作者 ZHANG Xilin TAN Yuejin and YANG Zhiwei 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2019年第6期1132-1143,共12页
Resource allocation for an equipment development task is a complex process owing to the inherent characteristics,such as large amounts of input resources,numerous sub-tasks,complex network structures,and high degrees ... Resource allocation for an equipment development task is a complex process owing to the inherent characteristics,such as large amounts of input resources,numerous sub-tasks,complex network structures,and high degrees of uncertainty.This paper presents an investigation into the influence of resource allocation on the duration and cost of sub-tasks.Mathematical models are constructed for the relationships of the resource allocation quantity with the duration and cost of the sub-tasks.By considering the uncertainties,such as fluctuations in the sub-task duration and cost,rework iterations,and random overlaps,the tasks are simulated for various resource allocation schemes.The shortest duration and the minimum cost of the development task are first formulated as the objective function.Based on a multi-objective particle swarm optimization(MOPSO)algorithm,a multi-objective evolutionary algorithm is constructed to optimize the resource allocation scheme for the development task.Finally,an uninhabited aerial vehicle(UAV)is considered as an example of a development task to test the algorithm,and the optimization results of this method are compared with those based on non-dominated sorting genetic algorithm-II(NSGA-II),non-dominated sorting differential evolution(NSDE)and strength pareto evolutionary algorithm-II(SPEA-II).The proposed method is verified for its scientific approach and effectiveness.The case study shows that the optimization of the resource allocation can greatly aid in shortening the duration of the development task and reducing its cost effectively. 展开更多
关键词 resource allocation equipment development task multi-objective particle swarm optimization(MOPSO) develop ment task simulation.
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3D-pCASL在评估妊娠期高血压对早产儿脑发育影响中的价值 被引量:2
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作者 李思柯 程美英 +6 位作者 张灵洁 鲁钰 冯占起 刘世鹏 冯刘娟 周梁 赵鑫 《磁共振成像》 北大核心 2025年第2期7-13,共7页
目的应用三维准连续动脉自旋标记(three-dimensional pseudo-continuous arterial spin labeling,3D-pCASL)成像技术定量评估妊娠期高血压孕妇分娩的早产儿脑血流量(cerebral blood flow,CBF)值,并深入探讨CBF值与早产儿炎症因子水平及... 目的应用三维准连续动脉自旋标记(three-dimensional pseudo-continuous arterial spin labeling,3D-pCASL)成像技术定量评估妊娠期高血压孕妇分娩的早产儿脑血流量(cerebral blood flow,CBF)值,并深入探讨CBF值与早产儿炎症因子水平及新生儿神经行为测定(Neonatal Behavioral Neurological Assessment,NBNA)评分之间的潜在关联。材料与方法本研究前瞻性分析2023年7月至2024年6月于我院就诊的80例早产儿,依据其母亲是否患有妊娠期高血压分为病例组(40例)和对照组(40例)。两组早产儿均行常规MRI及3D-pCASL序列扫描,组间比较两组早产儿各脑区CBF值,并分析CBF值与炎症因子和NBNA评分的相关性。结果母亲患有妊娠期高血压的早产儿多个脑区CBF值和炎症因子水平均显著高于对照组(P<0.05),而NBNA评分则低于对照组(P<0.05)。其中左侧额叶、右侧颞叶、左侧顶叶、双侧基底节区及丘脑的CBF值与降钙素原呈现一定的正相关(r=0.399、0.469、0.482、0.535、0.606、0.692、0.689,P<0.05),双侧基底节区与丘脑的CBF值与NBNA评分呈负相关(r=−0.395、−0.429、−0.414、−0.438,P<0.05)。结论3D-pCASL技术可无创评估妊娠期高血压孕妇分娩的早产儿脑CBF值,CBF值升高可能与其预后不良有关,这将有助于早产儿脑发育不良的早期诊断及干预治疗。 展开更多
关键词 早产儿 脑发育 妊娠期高血压 动脉自旋标记成像 磁共振成像 炎症因子 新生儿神经行为测定评分
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舞毒蛾V-ATPaseA基因dsRNA原核表达及其对生长发育的影响
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作者 刘艳涛 王晓琪 +2 位作者 张新华 孙丽丽 曹传旺 《北京林业大学学报》 北大核心 2025年第9期99-109,共11页
【目的】探究舞毒蛾液泡型H+-ATP酶V-ATPaseA基因对蜕皮、生殖和生长发育等生理活动的影响,评估其作为舞毒蛾RNA干扰(RNAi)绿色防控靶标的潜力,为鳞翅目害虫新型生物农药开发提供参考。【方法】首先,克隆舞毒蛾VATPaseA基因开放阅读框(O... 【目的】探究舞毒蛾液泡型H+-ATP酶V-ATPaseA基因对蜕皮、生殖和生长发育等生理活动的影响,评估其作为舞毒蛾RNA干扰(RNAi)绿色防控靶标的潜力,为鳞翅目害虫新型生物农药开发提供参考。【方法】首先,克隆舞毒蛾VATPaseA基因开放阅读框(ORF)序列,利用qRT-PCR分析舞毒蛾不同发育时期及组织中V-ATPaseA基因的表达特征。随后,构建LdV-ATPaseA基因原核表达载体,并转化至HT115(DE3)菌株,经IPTG诱导后制备表达dsRNA的菌液,连续饲喂舞毒蛾2龄和3龄幼虫。试验统计取食量、体重、体重累计增长率、死亡率、化蛹率、蛹质量、产卵量和发育历期等指标。【结果】结果显示,LdV-ATPaseA基因在舞毒蛾整个生命周期中持续表达,且表达水平呈组织特异性,其中精巢表达量最高(为对照脂肪体的30.80倍),其次为卵巢(12.82倍)和表皮(9.66倍)。对舞毒蛾2龄和3龄幼虫连续饲喂添加表达dsLdV-ATPaseA菌液的人工饲料均可显著沉默靶标基因,导致3龄~5龄幼虫取食量、体重、体重累计增长率显著降低,幼虫累计死亡率显著增加,雌蛹质量显著降低;此外,对舞毒蛾2龄幼虫连续饲喂添加表达dsLdV-ATPaseA菌液的人工饲料可导致2龄~6龄幼虫及蛹期发育历期显著延长,化蛹率显著降低,蛹期畸形率显著升高,雌成虫产卵量显著降低。【结论】V-ATPaseA基因显著干扰舞毒蛾蜕皮、生殖及生长发育,表现为取食减少、生长受阻、死亡率升高、发育延迟、蛹畸形增加及繁殖力下降。因此,LdV-ATPaseA基因可作为RNAi介导绿色防控的理想靶点,本研究为鳞翅目害虫生物农药的研发提供了新的理论依据。 展开更多
关键词 液泡型H+-aTP酶 RNa干扰 原核表达 舞毒蛾 生长发育
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围氏马尾藻(Sargassum wightii)周年生长及有性生殖的早期发育研究
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作者 曾昭钧 孙立伟 谢恩义 《热带海洋学报》 北大核心 2025年第1期44-52,共9页
围氏马尾藻(Sargassum wightii)是广西涠洲岛、广东徐闻等海域的习见物种,为大型经济海藻。了解大型藻类的周年生长情况及其早期发育过程,可以推测藻体成熟时间并为其人工育苗和栽培等提供科学依据。本文报道了广东徐闻海域生活的围氏... 围氏马尾藻(Sargassum wightii)是广西涠洲岛、广东徐闻等海域的习见物种,为大型经济海藻。了解大型藻类的周年生长情况及其早期发育过程,可以推测藻体成熟时间并为其人工育苗和栽培等提供科学依据。本文报道了广东徐闻海域生活的围氏马尾藻的周年生长特点、温度对其排卵的影响及其有性生殖的早期发育过程,围氏马尾藻周年生长情况可分为快速生长期、成熟期、衰退期和休止期4个时期,藻体平均长度在4月初达到最长(188.32±43.77)cm, 4月和5月的藻体月平均长度均超过180cm,而在7月下旬至11月上旬不超过5cm;围氏马尾藻为雌雄同托,卵细胞发育属8核1卵型;培养温度对其排卵过程至关重要,生殖托在15、27、30℃培养下无法排卵,在18~24℃培养下均可排卵, 24℃培养下排卵时间最短,仅需3d便可排卵;受精卵在24℃下培养24h左右发育形成有假根的幼孢子体,幼苗培养30d便发育出第四片叶片。本研究结果为围氏马尾藻的生物学、生态学研究提供了基础资料,为其人工育苗和栽培提供了科学依据。 展开更多
关键词 围氏马尾藻 大型海藻 周年生长 有性生殖 早期发育 排卵
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Development and Application of a Shaft-type Tubular Pumping System with a Siphon Discharge Passage 被引量:7
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作者 ZHANG Ren-tian ZHU Hong-geng DAI Long-yang 《南水北调与水利科技》 CAS CSCD 北大核心 2013年第1期J0001-J0006,共6页
Based on the characteristics of large flow rate , low head , short annual operation time , and high reliability of the city flood-control pumping stations , a new-type shaft tubular pumping system featuring a shaft su... Based on the characteristics of large flow rate , low head , short annual operation time , and high reliability of the city flood-control pumping stations , a new-type shaft tubular pumping system featuring a shaft suction box and a siphon-type discharge passage with a vacuum breaker as the cutoff device was developed , which possesses such advantages as simple structure , reliable cutoff , and high energy performance.Taking some pumping stations as the case studies , in the light of the specified operation conditions , the hydraulic optimal design of the shaft-type tubular pumping system was determined and the optimized shape of the system was recommended.The performance prediction based on the computational fluid dynamics methodology was determined and the model test verification was conducted.The results show that the predicted data agree with the experimental head and efficiency so that both methods can be used to determine the performance of a real pumping station.Finally , the in-situ measurements of a pumping station during the commissioning period further verified that the shaft-type tubular pumping station with a siphon discharge passage is of higher efficiency , more reliable and stable. 展开更多
关键词 shaft-type tubular pumping station siphon discharge passage development application hydraulic optimal design model test
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Research Status and Development Direction of Gas-containing Coal Seepage Model 被引量:17
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作者 程波 《矿业安全与环保》 北大核心 2017年第5期93-97,共5页
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Design and Development of TGPSIS Based on SuperMap—Map Subsystem 被引量:1
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作者 LI Changzhi~1 LIU Xingnian~2 CAO Shuyou~2 WANG Zhaoyin~(1,3) (1.China Inst.of Water Resources and Hydropower Research,Beijing 100038,China 2.State Key Lab.of Hydraulics and Mountain River Eng.,Sichuan Univ.,Chengdu 610065,China 3.Dept.of Hydraulic Eng.,Tsinghua Univ.,Beijing 100084,China) 《四川大学学报(工程科学版)》 EI CAS CSCD 北大核心 2005年第S1期133-137,共5页
The Three Gorges Project (TGP for short) is the key project to train and develop the Yangtze River of China,with multi-objects of flood defence,electricity generation,shipping,etc.However,sediment plays an important r... The Three Gorges Project (TGP for short) is the key project to train and develop the Yangtze River of China,with multi-objects of flood defence,electricity generation,shipping,etc.However,sediment plays an important role in beth constructing of engineering and exerting efficiency of TGP.Special attention,there- fore,has been paid to sediment problem of TGP since the very beginning of this engineering's pregnancy.Up to now,much observed data and fruitful researches about TGP have come into being,and a sci... 展开更多
关键词 TGPSIS SEDIMENT design and development
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A new approach for selecting best development face ventilation mode based on G1-coefficient of variation method 被引量:15
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作者 ZHOU Zhi-yong Mehmet KIZIL +1 位作者 CHEN Zhong-wei CHEN Jian-hong 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第10期2462-2471,共10页
The current popular methods for decision making and project optimisation in mine ventilation contain a number of deficiencies as they are solely based on either subjective knowledge or objective information.This paper... The current popular methods for decision making and project optimisation in mine ventilation contain a number of deficiencies as they are solely based on either subjective knowledge or objective information.This paper presents a new approach to rank the alternatives by G1-coefficient of variation method.The focus of this approach is the use of the combination weighing,which is able to compensate for the deficiencies in the method of evaluation index single weighing.In the case study,an appropriate evaluation index system was established to determine the evaluation value of each ventilation mode.Then the proposed approach was used to select the best development face ventilation mode.The result shows that the proposed approach is able to rank the alternative development face ventilation mode reasonably,the combination weighing method had the advantages of both subjective and objective weighing methods in that it took into consideration of both the experience and wisdom of experts,and the new changes in objective conditions.This approach provides a more reasonable and reliable procedure to analyse and evaluate different ventilation modes. 展开更多
关键词 development face ventilation G1 method coefficient of variation method comprehensive evaluation OPTIMIZaTION
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Rehabilitation of bauxite residue to support soil development and grassland establishment 被引量:9
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作者 XUE Sheng-guo 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第2期353-360,共8页
Rehabilitation(amendment and vegetation establishment)on bauxite residue is viewed as a promising strategy to stabilize the surface and initiate soil development.However,such approaches are inhibited by high pH,high e... Rehabilitation(amendment and vegetation establishment)on bauxite residue is viewed as a promising strategy to stabilize the surface and initiate soil development.However,such approaches are inhibited by high pH,high exchangeable sodium(ESP)and poor nutrient status.Amendment with gypsum is effective in improving residue physical and chemical properties and promoting seed establishment and growth.Application of organics(e.g.compost)can address nutrient deficiencies but supplemental fertilizer additions may be required.A series of germination bioassays were performed on residue to determine candidate species and optimum rehabilitation application rates.Subsequent field trials assessed establishment of grassland species Holcus lanatus and Trifolium pratense as well as physical and chemical properties of amended residue.Follow up monitoring over five years assessed elemental content in grassland and species dynamics.With co-application of the amendments several grassland species can grow on the residue.Over time other plant species can invade the restored area and fast growing nutrient demanding grasses are replaced.Scrub species can establish within a 5 Yr period and there is evidence of nutrient cycling.High pH,sodicity and nutrient deficiencies are the major limiting factors to establishing grassland on residue.Following restoration several plant species can grow on amended residue. 展开更多
关键词 bauxite residue substrate amendment soil development soil formation in bauxite residue vegetation establishment
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Rural Development Evaluation from Territorial Function Angle:a Case of Shandong Province 被引量:1
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作者 CHEN Yangfen LIU Yansui 《Journal of Northeast Agricultural University(English Edition)》 CAS 2011年第1期67-74,共8页
Rural territorial function follows the trend to develop from agricultural production space to a complex of cultural heritage,food security,social stability,quality of living,etc.Based on the rural area's territorial ... Rural territorial function follows the trend to develop from agricultural production space to a complex of cultural heritage,food security,social stability,quality of living,etc.Based on the rural area's territorial function to both urban and rural areas and its evolution law,index system of rural development evaluation,covering rural production function,rural consumption function,regional sustaining function,and individual development function were constructed in this paper.Case study based on Shandong Province and entropy method showed that the rural development in Shandong Province was neither stable nor orderly,and some of rural territorial functions were under fluctuation.The simulation result was close to the actual situation in rural areas of Shandong Province,and therefore,it would provide some experience for scientific evaluation of rural development in other regions.In the end,policy suggestion to cope with rural function transition was provided,namely further promoting the rural economic development,and breaking away from various factors that restricted the value realization,natural increment,and equitable distribution of rural production factors,and therefore,it would receive a sustainable rural development. 展开更多
关键词 rural territorial function rural development EVaLUaTION entropy method
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