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Design of a straw picking and cutting device

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International Journal of Agricultural and Biological Engineering 2021年第6期14卷 93-98页

作者： Kai Xu Yanyan Ge Maohua Xiao Min Kang Jie ni Jinwu Wang College of Engineering Nanjing Agricultural UniversityNanjing 211800China Shandong Daye Co. Ltd.Zhucheng 262218ShandongChina

In order to improve the effective recovery of straw,a new type of straw picking and cutting device was designed.A new type of roller moving knife mechanism was used which can realize simultaneous picking and cutting.A hammer claw was used to pick up and cut straw for the first time,and a roller moving knife was used to cut straw for the second *** software was used to conduct static and modal analyses of the moving roller shaft and optimize the structure of the cutting part and the staggered arrangement of hammer *** first-order resonance frequency of the hammer claw shaft is 205.84 Hz,and the first-order natural frequency of the pulling roller moving knife mechanism is 214.35 Hz,which can avoid resonance and realize efficient picking and cutting of straw.

关键词： straw hammer claw roller moving knife mechanism fixed knife

Multifractal analysis of resting state fMRI series in default mode network: age and gender effects

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Chinese Science Bulletin 2014年第25期59卷 3107-3113页

作者： Huangjing ni Xiaolin Huang Xinbao ning Chengyu Huo Tiebing Liu De Ben School of Electronic Science and Engineering Nanjing University School of Physics and Electronic Engineering Changshu Institute of Technology Department of Biomedical Engineering Jinling Hospital

Age-related changes of resting state in default mode network(DMN)may provide new clues to the developing mechanism of normal brain as well as early diagnosis and therapy of some neuropsychiatric *** application of multifractal theory to functional magnetic resonance imaging(fMRI)signals has recently raised increasing *** aim to explore the multifractal characteristics underlying the resting state functional magnetic resonance imaging(rs-fMRI)series extracted from DMN,and two issues are mainly discussed:(1)whether there exist multifractals in rs-fMRI series;(2)whether it is possible to distinguish between the different ages or genders by means of multifractal *** demonstrated the existence of multifractals in rs-fMRI series in *** addition,slight differences between young subjects and middle-aged or elderly subjects can be successfully detected by Dasa,a modified measure we ***,it is revealed that the rs-fMRI series from young subjects possess smaller averaged scale index and weaker long range correlation,while those from middle-aged or elderly people present increasing averaged scale index andstronger long range *** no significant statistical differences has been found between male and female *** results,therefore,highlight the potential usefulness of multifractal analysis in fMRI series of a certain brain region,and provide important insights into healthy aging in DMN.

关键词：多重分形分析功能磁共振成像年龄相关状态静息性别网络磁共振成像技术

高光谱结合化学计量学对粉底液的分类检验研究

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实验与分析 2024年第1期2卷 54-60页

作者：倪昕蕾李春宇姜红孔维刚中国人民公安大学侦查学院北京100038 甘肃警察职业学院刑事侦查系甘肃兰州730046 郑州市公安局刑事科学技术研究所河南郑州450000

为建立一种快速、无损的粉底液分类方法,将市面上随机收集的50个不同品牌、不同色号、不同产地、不同价位的粉底液在高光谱模式下选取波长范围在400~600nm进行无损检测,每组样本选取随机点位各测3次,共测得150组数据。将光谱数据采用Sav... 详细信息

为建立一种快速、无损的粉底液分类方法,将市面上随机收集的50个不同品牌、不同色号、不同产地、不同价位的粉底液在高光谱模式下选取波长范围在400~600nm进行无损检测,每组样本选取随机点位各测3次,共测得150组数据。将光谱数据采用Savitzky-Golay平滑处理,主成分分析对数据进行特征值提取,选取前7个主成分作为后续实验数据集;借助K-Means聚类法对150组数据分类,50个粉底液被分成5类,由Fisher判别式验证分类效果;最后以聚类结果为依据建立BP神经网络模型(BPNN),分类准确率达到88.89%,效果良好。研究表明BP神经网络结合高光谱技术自动识别、分类粉底液具有可行性和科学性,在公安机关物证检验及法庭科学上可发挥有效作用。

关键词：高光谱粉底液主成分分析 K-Means聚类 BP神经网络分类自动化

Esophagogastric devascularization without splenectomy in portal hypertension: safe and effective?

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Hepatobiliary & Pancreatic Diseases International 2015年第3期14卷 276-280页

作者： Yan-Bin ni Peng-Ji Gao Dong Wang Zhao Li Ji-Ye Zhu Department of Hepatobiliary Surgery Peking University People's Hospital

BACKGROUND： Esophagogastric variceal hemorrhage is a life-threatening complication of portal hypertension. In this study, we compared the therapeutic effect of a novel surgi- cal procedure, esophagogastric devascularization without splenectomy （EDWS）, with the widely used modified esopha- gogastric devascularization （MED） with splenectomy for the treatment of portal hypertension.

关键词： portal hypertension esophagogastric devascularization without splenectomy portal vein system thrombosis

Experimental evidence for weakened tree nutrient use and resorption efficiencies under severe drought in a subtropical monsoon forest

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Journal of Plant Ecology 2020年第5期13卷 649-656页

作者： Xiao-ni Xu Jian-Yang Xia Xu-Hui Zhou Li-Ming Yan Zhejiang Tiantong Forest Ecosystem National Observation and Research Station Shanghai Key Lab for Urban Ecological Processes and Eco-RestorationSchool of Ecological and Environmental SciencesEast China Normal UniversityShanghai 200241China Research Center for Global Change and Ecological Forecasting East China Normal UniversityShanghai 200241China

Aims The functions of global forests are threatened by the increasing frequency of severe *** to drought inducing reductions in soil nutrient availability,efficiencies of nutrient use and resorption of trees become crucial for forest functions and biogeochemical ***,understanding the dynamics of responses of foliar nutrient use and resorption efficiencies to drought,especially in tropical or subtropical forests,is still *** goal was to detect whether and how the importance of leaf nutrient use and resorption changes across different species in the hot and wet forests when suffering drought stress in different *** Based on a 70%throughfall exclusion experiment in a subtropical forest,we collected green and senesced leaves of Schima superba and Lithocarpus glaber in different months from October 2016 to May 2019,to estimate the effects of drought on leaf nitrogen(N)and phosphorus(P)use and resorption efficiencies(*** and PUE,NRE and PRE).Important Findings The effects of drought on nutrient use and resorption efficiencies varied between species and *** on a 2-year observation,drought had no effect on ***,but significantly decreased NUE,NRE and PRE of *** by 3.4%,20.2%and 7.1%,***,the negative drought effects were aggravated by the natural summer drying in *** a result,NUE and PUE of *** were significantly depressed by 17.2%and 58.1%,while NRE and PRE were significantly reduced by 56.5%and 53.8%in August ***,the responses of NRE,PRE and NUE to drought were related with soil moisture(SM)for ***,and when SM decreased to a threshold near 9 v/v%,drought effects were shifted from unresponsive to *** results highlight a species-specific threshold response of nutrient use under drought in a subtropical forest.

关键词： drought nitrogen nutrient resorption efficiency nutrient use efficiency phosphorus subtropical forest

A mini-review of noble-metal-free electrocatalysts for overall water splitting in non-alkaline electrolytes

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Materials Reports(Energy) 2021年第2期1卷 48-60页

作者： Jie Yu Yawen Dai Qijiao He Dongqi Zhao Zongping Shao Meng ni Department of Building and Real Estate The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong999077PR China School of Artificial Intelligence and Automation Key Laboratory of Image Processing and Intelligent Control of Education MinistryHuazhong University of Science and TechnologyWuhan430074PR China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing210009PR China Department of Chemical Engineering Curtin UniversityPerthWestern Australia6845Australia Environmental Energy Research Group Research Institute for Sustainable Urban Development(RISUD)The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong999077PR China

Development of noble-metal-free materials with remarkable electrocatalytic water-splitting performance in acidic or neutral media has sparked considerable attention in recent ***,we review the latest research on design and fabrication of precious-metal-free catalytic materials for overall water electrolysis in non-alkaline environment,especially highlighting several optimizing approaches to enhance the catalytic behavior and to realize effective bifunctional *** these involved noble-metal-free electrocatalysts are classified into transition-metal oxides(TMOs),transition-metal nitrides(TMNs),transition-metal carbides(TMCs),transition-metal phosphides(TMPs),transition-metal chalcogenides,metal complexes,and metal-free carbons,as shown in the main ***,the paper also offers an introduction of the fundamental electrochemistry of water splitting before entering the subject,as well as a prospective discussion on mechanism understanding,novel catalysts fabrication,and standardized performance measurements/evaluation in the last section.

关键词： Noble-metal-free electrocatalyst Overall water splitting Oxygen evolution reaction Hydrogen evolution reaction Non-alkaline electrolyte Bifunctional catalytic electrode

超微针刀松解颈肩部激痛点治疗颞下颌关节紊乱综合征临床观察

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浙江中西医结合杂志 2024年第4期34卷 356-358,361页

作者：倪芳英孙云廷边金寿升芸杭州市余杭区第二人民医院中医科杭州311121 杭州市中医院针灸康复科杭州310007

颞下颌关节紊乱综合征(temporomandibular di-sorders,TMD)是受凉、熬夜、过度咀嚼、口腔咬合、精神心理压力等多种因素作用下机制未明的,表现为单侧(少数双侧)颞下颌附近酸胀疼痛、张口受限、关节弹响绞锁等症状的颌面疼痛性疾病,常伴... 详细信息

颞下颌关节紊乱综合征(temporomandibular di-sorders,TMD)是受凉、熬夜、过度咀嚼、口腔咬合、精神心理压力等多种因素作用下机制未明的,表现为单侧(少数双侧)颞下颌附近酸胀疼痛、张口受限、关节弹响绞锁等症状的颌面疼痛性疾病,常伴有头痛、耳鸣、颈肩部症状,以20~40岁青壮年女性多见^([1])。有学者发现,TMD患者的头颈姿势异于健康人,呈头前伸、前倾状态^([2-3])。

关键词：颞下颌关节紊乱超微针刀激痛点临床观察

Visualization of Water Plugging Displacement with Foam/Gel Flooding in Internally Heterogeneous Reservoirs

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Fluid Dynamics & Materials Processing 2021年第5期17卷 931-946页

作者： Jialiang Zhang Shumei He Tongjing Liu Tianlu ni Jian Zhou Fang Huang Dagang Oilfield Company China National Petroleum CorporationBinhai New AreaTianjin300280China The Unconventional Oil and Gas Institute China University of PetroleumBeijing102249China Beijing Jinshi Liyuan Science Co. Ltd.Beijing102206China

During the displacement of water plugging with binary flooding in internally heterogeneous reservoirs,it is essential to understand the distributions of remaining oil as well as the oil displacement mechanisms at different *** this study,two types of internally heterogeneous systems,i.e.,vertical and horizontal wells are investigated experimentally through a microscopic *** results show that plugging agent types have a greater impact on oil recovery than well types,and foam injection can enhance oil recovery more effectively than gel ***,the injection sequence of plugging agents significantly affects oil displacement *** gel after foam is more *** to the present results,the main formation mechanisms of remaining oil in each displacement stage are influenced by:capillary force,viscous force,inertial force,shear force,microscopic fingering&channeling.

关键词： Microscopic visualization experiment internally heterogeneous reservoir remaining oil foam gel

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水性脱模剂对混凝土外观气泡影响的研究

四川建材 2024年第8期50卷 32-34页

作者：宋欣倪涛汪咏梅封柯 Serina NG 四川砼道科技有限公司四川成都610200 石家庄市长安育才建材有限公司河北石家庄051430

以菜籽油为基础制备了一款水性脱模剂,并通过数字图像和图像处理方法对比研究了菜籽油及其制成的水性脱模剂在不同振动时间和不同模板上对混凝土表面气孔的影响,研究发现在不同条件下,相较于油性脱模剂,水性脱模剂能够有效减少混凝土表... 详细信息

以菜籽油为基础制备了一款水性脱模剂,并通过数字图像和图像处理方法对比研究了菜籽油及其制成的水性脱模剂在不同振动时间和不同模板上对混凝土表面气孔的影响,研究发现在不同条件下,相较于油性脱模剂,水性脱模剂能够有效减少混凝土表面气孔,尤其是大尺寸气孔的数量。此外,延长振动时间、选用表面光滑的模板也能有效降低混凝土表面气孔。

关键词：水性脱模剂混凝土表面气孔振动时间模板类型