检索结果-南通市图书馆

The Effects of Arbuscular Mycorrhizal Fungi on Reactive Oxyradical Scavenging System of Tomato Under Salt Tolerance

在线全文

学校读者我要写书评

暂无评论

Agricultural Sciences in China 2010年第8期9卷 1150-1159页

作者： HUANG Zhi HE Chao-xing HE Zhong-qun zou Zhi-rong ZHANG Zhi-bin College of Horticulture Northwest A&F University Yangling 712100 PR. China Institute of Vegetables and Flowers Chinese Academy of Agricultural Sciences Beijing 100081 P.R.China College of Horticulture Sichuan Agricultural University Ya'an 625014 P.R.China

The effects of arbuscular mycorrhizal fungi （AMF）, Glomus mosseae, on oxygen radical scavenging system of tomato under salt stress were studied in potted culture experiments. The response of tomato （Lycopersieon eseulentum L.） cultivar Zhongza 9 seedlings with AMF inoculation and control to salt stress （0, 0.5 and 1.0% NaCl solution, respectively） was investigated. The results showed that the salt stress significantly reduced the dry matter content of roots, stems and leaves, and also the leaf area as compared with the control treatment. However, arbuscular mycorrhizal-inoculated （AM） significantly improved the dry matter and the leaf area in the salt-stressed plants. The effect of AMF on dry matter was more pronounced in aerial bromass than in root biomass which might be due to AM colonization. The activities of SOD, POD, ASA-POD, and CAT in leaves and roots of mycorrhizal and non-mycorrhizal treatment of tomato plants were increased and had different rules under different NaCl concentrations （solution of 0, 0.5 and 1% NaCl）, but all enzymes had a rise in the beginning of treatment under salt stress conditions. The AMF did not change the rule of tomato itself under salt stress, but AMF increased these enzyme activities in different levels. The AMF treatment significantly increased SOD, POD and ASA-POD activities in leaves and roots, whereas it had little effects on CAT in root. O2- production rate and MDA content in leaves increased continuously, which showed a positive line correlation with salt stress concentration. O2- production rate and MDA content in tomato plants significantly decreased by AM treatment compared with nonmycorrhizal treatment. In conclusion, AM could alleviate the growth limitations imposed by saline conditions, and thereby play a very important role in promoting plant growth under salt stress in tomato.

关键词： arbuscular mycorrhizal fungi (AMF) osmoregulation salt stress tomato

工业打磨机器人机械臂运动偏离距离预补偿算法

在线全文

学校读者我要写书评

暂无评论

广州大学学报（自然科学版） 2024年第4期23卷 1-8页

作者：邹涛黄敬然项超群张建辉广州大学机械与电气工程学院广东广州510006

随着机器人技术的普及,其在生活、工业和服务领域的应用广泛增加。在实际应用中,机器人执行加工作业任务时常受外部因素或系统误差影响,导致运动轨迹偏离预期路径,影响任务完成效果。文章旨在研究工业打磨机器人机械臂运动过程中因误差... 详细信息

随着机器人技术的普及,其在生活、工业和服务领域的应用广泛增加。在实际应用中,机器人执行加工作业任务时常受外部因素或系统误差影响,导致运动轨迹偏离预期路径,影响任务完成效果。文章旨在研究工业打磨机器人机械臂运动过程中因误差与物理因素偏离原定轨迹的问题,重点关注优化机械臂运动偏离距离补偿。研究包括使用局部加权法调整偏离距离,降低测量误差影响,同时提出物理影响函数,考虑转动惯量、动摩擦及离心力等物理条件因子对偏离距离影响。研究结果显示,打磨机器人机械臂加工圆角倒角时,偏离距离预补偿算法使偏离距离误差从初始未修正的约0.22~0.83 mm减少至0.02~0.34 mm,且偏离浮动幅度减少了约52.46%,对提高打磨机器人工作效率和减少偏离误差具有重要意义。

关键词：偏离距离局部加权法物理影响函数距离误差补偿

“Exploring petroleum inside source kitchen”: Shale oil and gas in Sichuan Basin

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2020年第7期63卷 934-953页

作者： Caineng zou Zhi YANG Shasha SUN qun ZHAO Wenhua BAI Honglin LIU Songqi PAN Songtao WU Yilin YUAN PetroChina Research Institute of Petroleum Exploration and Development Beijing 100083China

The Sichuan Basin is rich in shale oil and gas resources,with favorable geological conditions that the other shale reservoirs in China cannot ***,the basin is an ideal option for fully"exploring petroleum inside source kitchen"with respect to onshore shale oil and gas in *** paper analyzes the characteristics of shale oil and gas resources in the United States and China,and points out that maturity plays an important role in controlling shale oil and gas *** shale oil and gas exhibit high proportions of light hydrocarbon and wet gas,whereas Chinese marine and transitional shale gas is mainly dry gas and continental shale oil is generally heavy.A comprehensive geological study of shale oil and gas in the Sichuan Basin reveals findings with respect to the following three ***,there are multiple sets of organic-rich shale reservoirs of three types in the basin,such as the Cambrian Qiongzhusi Formation and Ordovician Wufeng Formation-Silurian Longmaxi Formation marine shale,Permian Longtan Formation transitional shale,Triassic Xujiahe Formation lake-swamp shale,and Jurassic lacustrine *** shale gas enrichment is mainly controlled by four elements:Deep-water shelf facies,moderate thermal evolution,calcium-rich and silicon-rich rock association,and closed roof/***,the"sweet section"is generally characterized by high total organic carbon,high gas content,large porosity,high brittle minerals content,high formation pressure,and the presence of lamellation/bedding and natural ***,the"sweet area"is generally characterized by very thick organic-rich shale,moderate thermal evolution,good preservation conditions,and shallow burial depth,which are exemplified by the shale oil and gas in the Wufeng-Longmaxi Formation,Longtan Formation,and Daanzhai Member of the Ziliujing ***,the marine,transitional,and continental shale oil and gas resources in the Sichuan Basin account for 50%,25%,and 30%of the res

关键词： Shale oil Shale gas Marine facies Continental facies Transitional facies Resource potential Sweet area Sweet section Source rock oil and gas Shale oil and gas revolution "Sichuan-Chongqing Daqing-Gas"

Characterization of Cu-Zn Alloy Nanocrystalline Powders Prepared by Wire Electrical Explosion

在线全文

学校读者我要写书评

暂无评论

Chinese Physics Letters 2000年第2期17卷 145-147页

作者： WANG qun YANG Hai-Bin GUO Wei-Li zou Guang-Tian National Laboratory of Superhard Materials Jilin UniversityChangchun 130023

Nanocrystalline powders of Cu-Zn alloy in size ranging from 10 to 140nm was prepared from α-Cu-Zn alloy wire containing 39.8at.% Zn by an electrical explosion method. The particles are identified from x-ray diffraction as a mixture of the α,β,γ, and ε phases of Cu-Zn alloy. Most of the particles are hexagonal in shape, with only a small part being spherical and cubic. The composition of Zn in the explosion products varied from 6.9 to 45.2 at.% in different particles as determined by energy dispersive x-ray spectrometer. A possible mechanism for the formation of the alloy nanocrystalline powders is proposed, in which a redistribution process occurred caused by strong collision and diffusion between the two kinds of atoms during the powder formation.

关键词： alloy powders hexagonal

中国页岩气新区带、新层系和新类型勘探进展、挑战及对策

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

石油与天然气地质 2024年第2期45卷 309-326页

作者：邹才能董大忠熊伟傅国友赵群刘雯孔维亮张琴蔡光银王玉满梁峰刘翰林邱振中国石油勘探开发研究院北京100083 国家能源页岩气研发(实验)中心北京100083 中国石油大学(北京) 北京102249 中国石油天然气集团有限公司科技管理部北京100007

近年来,中国页岩气聚焦“三新”(尚未开展工作或工作程度低的新区带、新层系及新类型)领域,加大理论攻关与勘探力度,页岩气增储上产再上新台阶。基于中国页岩气“三新”领域理论与勘探新进展,分析其勘探特点、变化趋势和发展前景,探索... 详细信息

近年来,中国页岩气聚焦“三新”(尚未开展工作或工作程度低的新区带、新层系及新类型)领域,加大理论攻关与勘探力度,页岩气增储上产再上新台阶。基于中国页岩气“三新”领域理论与勘探新进展,分析其勘探特点、变化趋势和发展前景,探索中国特殊页岩气地质理论,明确页岩气发展挑战与对策。结果表明:中国在四川盆地及邻区创新建立了五峰组-龙马溪组特色的高-过成熟度海相页岩气富集理论,累计发现页岩气田9个,探明页岩气地质储量近3×10^(12)m^(3),形成了450×10^(8)m^(3)/a的页岩气产能,年产页岩气250×10^(8)m^(3)。明确了近年来中国页岩气“三新”领域勘探具三大特点:①四川盆地及邻区五峰组-龙马溪组在深层、极浅层勘探取得重大新发展;②四川盆地筇竹寺组和吴家坪组等多个新层系实现新突破;③鄂尔多斯盆地西缘乌拉力克组获得新发现,东缘山西组取得新突破。页岩气“三新”领域的勘探实现了三大战略性转变:①目标由单一类型、单一盆地和单一层系转变为多类型、多盆地和多层系;②选区由盆内或盆缘为主转变为盆内、盆缘兼顾盆外弱改造区;③思路由纯粹富有机质页岩转变为富有机质页岩系统。通过梳理中国页岩气“三新”领域勘探挑战,指出“三新”领域是中国页岩气可持续发展的方向,并提出了下一步发展对策。

关键词：勘探思路转变发展前景发展对策新区带新层系新类型页岩气中国

Jug-PLGA-NPs, a New Form of Juglone with Enhanced Efficiency and Reduced Toxicity on Melanoma

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Integrative Medicine 2022年第10期28卷 909-917页

作者： YUE Wu-heng QIN Lan-qun CAI Juan MEI Rui QIAN Han-qing zou Zheng-yun The Comprehensive Cancer Centre of Nanjing Drum Tower Hospital Clinical College of Traditional Chinese and Western MedicineNanjing University of Chinese MedicineNanjing(210008)China Department of Oncology Taicang TCM Hospital Affiliated to Nanjing University of Chinese MedicineSuzhouJiangsu Province(215499)China The Comprehensive Cancer Centre of Nanjing Drum Tower Hospital Clinical College of Nanjing Medical UniversityNanjing(210008)China The Comprehensive Cancer Centre of Nanjing Drum Tower Hospital Medical School of Nanjing University&Clinical Cancer Institute of Nanjing UniversityNanjing(210008)China

Objective: To verrify the anti-tumor efficacy and toxicity between juglone(Jug) and Jug-loaded poly lactic-co-glycolic acid(PLGA) nanoparticles(Jug-PLGA-NPs). Methods: Jug-PLGA-NPs were prepared by ultrasonic emulsification. The anti-tumor activity of Jug(2, 3, 4 μg/mL) and Jug-PLGA-NPs(Jug: 2, 3, 4 μg/mL) in vitro was measured by MTT assay and cell apoptosis analysis. The distribution, anti-tumor effect and biological safety in vivo was evaluated on A375 nude mice. Results: With the advantage of good penetration and targeting properties, Jug-PLGA-NPs significantly inhibited proliferation and migration of melanoma cells both in vitro and in vivo(P<0.05 or P<0.01) with acceptable biocompatibility. Conclusions: Jug can inhibit the growth of melanoma but is highly toxic. With the advantage of sustained release, tumor targeting, anti-tumor activity and acceptable biological safety, Jug-PLGA-NPs provide a new pharmaceutical form for future application of Jug.

关键词： juglone PLGA nanoparticles malignant melanoma Jug-PLGA-NPs

Local synchronization and amplitude of the fluctuation of spontaneous brain activity in attention-deficit/hyperactivity disorder:a resting-state fMRI study

在线全文

学校读者我要写书评

暂无评论

Neuroscience Bulletin 2013年第5期29卷 603-613页

作者： Li An Qing-jiu Cao Man-Qiu Sui Li Sun Qi-Hong zou Yu-Feng Zang Yu-Feng Wang Institute of Mental Health Peking University Key Laboratory of Mental Health Ministry of Health Peking University MRI Research Center and Beijing Key Lab of Medical Physics and Engineering Peking University Center for Cognition and Brain Disorders and The Affiliated Hospital Hangzhou Normal University Zhejiang Key Laboratory for Research in Assessment of Cognitive Impairments State Key Laboratory of Cognitive Neuroscience and Learning Beijing Normal University

Regional homogeneity（ReHo）and the amplitude of low-frequency fluctuation（ALFF）are two approaches to depicting different regional characteristics of resting-state functional magnetic resonance imaging（RS-fMRI）*** they can complementarily reveal brain regional functional abnormalities in attention-deficit/hyperactivity disorder（ADHD）remains *** this study,we applied ReHo and ALFF to 23 medication-na ve boys diagnosed with ADHD and 25 age-matched healthy male controls using whole-brain voxel-wise *** analyses were conducted in the ADHD group to investigate the relationship between the regional spontaneous brain activity measured by the two approaches and the clinical symptoms of *** found that the ReHo method showed widely-distributed differences between the two groups in the fronto-cingulo-occipitocerebellar circuitry,while the ALFF method showed a difference only in the right occipital *** a larger smoothing kernel and a more lenient threshold were used for ALFF,more overlapped regions were found between ALFF and ReHo,and ALFF even found some new regions with group *** ADHD symptom scores were correlated with the ReHo values in the right cerebellum,dorsal anterior cingulate cortex and left lingual gyrus in the ADHD group,while no correlation was detected between ALFF and ADHD *** conclusion,ReHo may be more sensitive to regional abnormalities,at least in boys with ADHD,than *** ALFF may be complementary to ReHo in measuring local spontaneous *** of the two may yield a more comprehensive pathophy-siological framework for ADHD.

关键词： resting state functional magnetic resonance imaging regional homogeneity amplitude of low-frequency fluctuation attention-deficit/hyperactivity disorder

在线全文

学校读者我要写书评

暂无评论

核事故辐射损伤伤员快速分类诊断方法研究

海军医学杂志 2024年第8期45卷 796-799页

作者：陈伟罗群李珂娴马丽邹赢锌海军军医大学海军特色医学中心上海200433

目的建立核事故辐射损伤伤员受照剂量快速诊断方法,并编写快速分类诊断程序。方法采用德尔菲(Delphi)专家咨询法进行2轮咨询,筛选诊断指标,应用层次分析(AHP)法确立指标权重,将其与评价指标的程度分级相结合,建立核事故辐射损伤伤员快... 详细信息

目的建立核事故辐射损伤伤员受照剂量快速诊断方法,并编写快速分类诊断程序。方法采用德尔菲(Delphi)专家咨询法进行2轮咨询,筛选诊断指标,应用层次分析(AHP)法确立指标权重,将其与评价指标的程度分级相结合,建立核事故辐射损伤伤员快速分类诊断方法。结果2轮问卷调查的回收率均大于90%,2轮咨询专家的权威系数均大于0.8,专家的积极程度和权威程度均较高。经过2轮专家咨询,筛选出15项指标,并确定各项指标的权重,最终构建了一套简明实用的核事故辐射损伤伤员快速分类诊断方法及程序。结论通过Delphi法和AHP法结合,构建的快速分类诊断方法科学可行,能为核事故辐射损伤伤员快速分类诊断提供客观、可量化的依据。

关键词：核事故伤员辐射损伤专家咨询法分类诊断

基于3D-Slicer上颌骨自体骨移植供骨量及其相关因素分析

在线全文

学校读者我要写书评

暂无评论

口腔颌面修复学杂志 2024年第4期25卷 259-263,304页

作者：毛丽莎袁鼎翔邹婷婷王学玖首都医科大学附属北京口腔医院口腔显微诊疗中心北京100162 首都医科大学附属北京口腔医院口腔颌面整形创伤外科北京100050

目的:通过3D-Slicer软件三维重建并测量上颌骨前鼻棘、硬腭、上颌结节等区域潜在取骨量及骨密度,为上颌骨作为自体骨移植潜在取骨位点的临床应用提供参考。方法:应用3D-Slicer软件对129例颅颌面CBCT数据进行三维重建,测量前鼻棘、硬腭... 详细信息

目的:通过3D-Slicer软件三维重建并测量上颌骨前鼻棘、硬腭、上颌结节等区域潜在取骨量及骨密度,为上颌骨作为自体骨移植潜在取骨位点的临床应用提供参考。方法:应用3D-Slicer软件对129例颅颌面CBCT数据进行三维重建,测量前鼻棘、硬腭、上颌结节的潜在取骨量、骨密度。对其在不同性别、年龄人群中的特点进行分析比较。结果:1.硬腭区域可取骨量最大(1512.31±71.93 mm^(3)),前鼻棘区可取骨量最小(444.74±17.49 mm^(3))。前鼻棘取骨区域的骨密度最高(HU:601.28±7.76),上颌结节取骨区域的骨密度最低(HU:259.84±5.44)。2.男性前鼻棘、硬腭、上颌结节区域的潜在取骨体积均大于女性。3.中老年组(≥40岁)在前鼻棘区域的潜在取骨体积大于青年组(<40岁)。结论:前鼻棘、硬腭、上颌结节可分别作为颌骨小型、中型骨缺损的口内自体骨移植取骨位点。

关键词： 3D-Slicer 骨增量自体骨移植上颌骨