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Tree allometry responses to competition and complementarity in mixed-species plantations of Betula alnoides

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Forest Ecosystems 2024年第4期11卷 469-479页

作者： boyao Chen Kaili Liu Chunsheng wang Junjie Guo Junkun Lu Lin Chen Zhigang Zhao Jie Zeng Research Institute of Tropical Forestry Chinese Academy of ForestryGuangzhou510520China Central South University of Forestry&Technology Changsha410004China Experimental Center of Tropical Forestry Chinese Academy of ForestryPingxiang532600China Nanjing Forestry University Nanjing210037China

Tree allometry plays a crucial role in tree survival,stability,and timber quantity and quality of mixed-species ***,the responses of tree allometry to resource utilisation within the framework of interspecific competition and complementarity remain poorly *** into consideration strong-and weakspace competition(SC and WC),as well as N_(2)-fixing and non-N_(2)-fixing tree species(FN and nFN),a mixedspecies planting trial was conducted for Betula alnoides,a pioneer tree species,which was separately mixed with Acacia melanoxylon(SC+FN),Erythrophleum fordii(WC+FN),Eucalyptus cloeziana(SC+nFN)and Pinus kesiya ***(WC+nFN)in southern *** years after planting,tree growth,total nitrogen(N)and carbon(C)contents,and the natural abundances of^(15)N and^(13)C in the leaves were measured for each species,and the mycorrhizal colonisation rates of *** were investigated under each *** variations and their relationships with space competition and nutrient-related factors were *** results showed a consistent effect of space competition on the height-diameter relationship of *** in mixtures with FN or *** tree height growth of *** was significantly promoted under high space competition,and growth in diameter at breast height(DBH),tree height and crown size were all expedited in mixtures with *** symbiotic relationship between ectomycorrhizal fungi and *** was significantly influenced by both space competition and N_(2) fixation by the accompanying tree species,whereas such significant effects were absent for arbuscular mycorrhizal ***,high space competition significantly decreased the water use efficiency(WUE)of ***,and its N use efficiency(NUE)was much lower in the FN *** equation modeling further demonstrated that the stem allometry of *** was affected by its NUE and WUE via changes in its height growth,and crown allometry was influ

关键词： Allometric relationship Resources competition and complementarity Mixed-species forest Tree-fungal symbiotic relationship N_2-fixing tree species Resource utilisation strategies

铝管与泡沫层胶接结构脱黏缺陷的空气耦合超声检测

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无损检测 2024年第2期46卷 6-9页

作者：肖轲迪高晨家陈博吴君豪王博尧吴时红金珂徐林航天材料及工艺研究所北京100076

针对铝管与泡沫隔热层胶接结构脱黏缺陷的检测问题,开展了检测技术研究和脱黏缺陷类型分析。根据胶接结构的特点,制作了人工缺陷试样,使用空气耦合超声穿透法进行C扫描成像检测,并对扫描发现的异常区域进行微焦点CT检测分析,归纳了脱黏... 详细信息

针对铝管与泡沫隔热层胶接结构脱黏缺陷的检测问题,开展了检测技术研究和脱黏缺陷类型分析。根据胶接结构的特点,制作了人工缺陷试样,使用空气耦合超声穿透法进行C扫描成像检测,并对扫描发现的异常区域进行微焦点CT检测分析,归纳了脱黏缺陷的类型及其成因。试验结果表明,空气耦合超声穿透法能有效检出材料中的脱黏缺陷,脱黏缺陷的成因包括型面不贴合引起胶层未填满和胶层内空气未完全排出产生了间隙层。

关键词：胶接结构脱黏缺陷空气耦合超声检测微焦点CT检测

Recent advances in two-dimensional layered and non-layered materials hybrid heterostructures

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Chinese Physics B 2022年第10期31卷 231-246页

作者： Haixin Ma Yanhui Xing boyao Cui Jun Han Binghui wang Zhongming Zeng Key Laboratory of Opto-electronics Technology Ministry of EducationCollege of MicroelectronicsBeijing University of TechnologyBeijing 100124China Key Laboratory of Nanodevices and Applications Suzhou Institute of Nano-tech and Nano-bionicsChinese Academy of SciencesSuzhou 215123China Nanchang Nano-Devices and Technologies Division Suzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesNanchang 330200China

With the development of Moore's law, the future trend of devices will inevitably be shrinking and integration to further achieve size reduction. The emergence of new two-dimensional non-layered materials(2DNLMs) not only enriches the 2D material family to meet future development, but also stimulates the global enthusiasm for basic research and application technologies in the 2D field. Van der Waals(vd W) heterostructures, in which two-dimensional layered materials(2DLMs)are physically stacked layer by layer, can also occur between 2DLMs and 2DNLMs hybrid heterostructures, providing an alternative platform for nanoelectronics and optoelectronic applications. Here, we outline the recent developments of2DLMs/2DNLMs hybrid heterostructures, with particular emphasis on major advances in synthetic methods and applications. And the categories and crystal structures of 2DLMs and 2DNLMs are also shown. We highlight some promising applications of the heterostructures in electronics, optoelectronics, and catalysis. Finally, we provide conclusions and future prospects in the 2D materials field.

关键词： 2D layered materials 2D non-layered materials van der Waals heterostructure applications

Three-dimensional magnetization reconstruction from electron optical phase images with physical constraints

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 122-132页

作者： boyao Lyu Shihua Zhao Yibo Zhang Weiwei wang Fengshan Zheng Rafal E.Dunin-Borkowski Jiadong Zang Haifeng Du Anhui Province Key Laboratory of Low-Energy Quantum Materials and Devices High Magnetic Field LaboratoryHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Science Island Branch Graduate School of University of Science and Technology of ChinaHefei 230026China Department of Physics and Astronomy University of New HampshireDurham 03824USA Department of Physics The City College of New YorkNew York 10031USA Physics Program Graduate Center of the City University of New YorkNew York 10016USA Department of Chemistry University of New HampshireDurham 03824USA Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601China Spin-X Institute Center for Electron MicroscopySchool of Physics and OptoelectronicsState Key Laboratory of Luminescent Materials and DevicesGuangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional MaterialsSouth China University of TechnologyGuangzhou 511442China Ernst Ruska-Centre for Microscopy and Spectroscopy with Electrons Forschungszentrum JülichJülich 52425Germany

The ability to characterize three-dimensional(3D)magnetization distributions in nanoscale magnetic materials and devices is essential to fully understand their static and dynamic magnetic *** contrast techniques in the transmission electron microscope(TEM),such as electron holography and electron ptychography,can be used to record two-dimensional(2D)projections of the in-plane magnetic induction of 3D nanoscale *** the 3D magnetic induction can in principle be reconstructed from one or more tilt series of such 2D projections,conventional tomographic reconstruction algorithms do not recover the 3D magnetization within a sample ***,we use simulations to describe the basis of an improved model-based algorithm for the tomographic reconstruction of a 3D magnetization distribution from one or more tilt series of electron optical phase images recorded in the *** algorithm allows a wide range of physical constraints,including a priori information about the sample geometry and magnetic parameters,to be *** also makes use of minimization of the micromagnetic energy in the loss *** demonstrate the reconstruction of the 3D magnetization of a localized magnetic soliton—a hopfion ring—and discuss the influence of noise,choice of magnetic constants,maximum tilt angle and number of tilt axes on the *** algorithm can in principle be adapted for other magnetic contrast imaging techniques in the TEM,as well as for other magnetic characterization techniques,such as those based on X-rays or neutrons.

关键词： three-dimensional magnetization vector field tomography differentiable programming electron holography micromagnetism

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脊柱手术机器人研究的现状和展望

中华实验外科杂志 2024年第11期41卷 2421-2423页

作者：伏佳驹徐寅阳陈研松眭涛余利鹏王伯尧曹晓建南京医科大学第一附属医院(江苏省人民医院)骨科南京南京医科大学第二附属医院骨科南京

脊柱手术机器人进入临床已经有20年的历史, 目前主要用于辅助椎弓根螺钉植入, 脊柱手术机器人能显著提高植钉准确性, 减少了患者和术者辐射暴露。未来脊柱手术机器人的适应症将继续扩大, 从现今的仅能行开放式和经皮放置椎弓根螺钉, 发... 详细信息

脊柱手术机器人进入临床已经有20年的历史, 目前主要用于辅助椎弓根螺钉植入, 脊柱手术机器人能显著提高植钉准确性, 减少了患者和术者辐射暴露。未来脊柱手术机器人的适应症将继续扩大, 从现今的仅能行开放式和经皮放置椎弓根螺钉, 发展至能够开展自动规划、自动置钉、自动活检与椎体成形手术、自动行椎管减压截骨与椎间融合器植入、以及远程手术等功能;机器人辅助脊柱手术技术与人工智能(AI)技术相融合, 人工智能技术的应用能推动手术机器人系统的自动化水平, 脊柱手术机器人高度智能化将是未来发展的趋势。

关键词：脊柱外科手术机器人现状和展望

Magnetic polyamidoamine dendrimers for magnetic separation and sensitive determination of organochlorine pesticides from water samples by high-performance liquid chromatography

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Journal of Environmental Sciences 2021年第4期33卷 64-73页

作者： Qingxiang Zhou Yalin Wu Yi Sun Xueying Sheng Yayan Tong Jinghan Guo boyao Zhou Jingyi Zhao State Key Laboratory of Heavy Oil Processing China University of Petroleum-BeijingBeijing 102249China Beijing Municipal Research Institute of Environmental Protection Beijing 100037China

Organochlorine pesticides(OCPs)have received much attention due to their *** methods to monitor their residues in the environment are ***,magnetic polyamidoamine dendrimers were prepared by co-precipitation,Michael addition,and *** magnetic polyamidoamine dendrimers demonstrated good adsorption ability for OCPs—this feature was utilized to construct a sensitive tool for monitoring OCPs in water *** proposed method provided remarkable linearity from 0.1 to 500μg/L and satisfactory limits of detection from 0.012 to 0.029μg/*** spiked recoveries of the four target analytes were 91.8%-103.5%with relative standard deviations less than 4.5%.The magnetic materials had good *** results indicated that the resulting method was an efficient,easy,rapid,economical,and eco-friendly tool for monitoring OCPs in aqueous samples.

关键词： Organochlorine pesticides Magnetic PAMAM dendrimers Fe_(3)O_(4)nanoparticles

以颈部抬起无力为首发表现的颅内静脉窦血栓1例报告

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华北理工大学学报（医学版） 2024年第1期26卷 75-77页

作者：吴浩凯王博瑶张光宇郑富霞范海燕王秀杰李群喜赵晓晶华北理工大学附属医院神经内科四病区河北唐山063000 华北理工大学附属医院神经外科二病区河北唐山063000

颅内静脉窦血栓形成(cerebral venous sinus thrombosis,CVST)是一种缺血性脑血管疾病,临床上较为少见且临床表现无明显特异性。华北理工大学附属医院神经内科四病区收治的1例以颈部抬起无力为首发症状的颅内静脉窦血栓形成患者,现对其... 详细信息

颅内静脉窦血栓形成(cerebral venous sinus thrombosis,CVST)是一种缺血性脑血管疾病,临床上较为少见且临床表现无明显特异性。华北理工大学附属医院神经内科四病区收治的1例以颈部抬起无力为首发症状的颅内静脉窦血栓形成患者,现对其临床资料进行报道并对相关文献进行复习,以讨论颅内静脉窦血栓形成的病因、发病机制、临床表现、辅助检查、治疗及预后,旨在为此类患者的早期诊治提供参考性意见。

关键词：颅内静脉窦血栓临床表现治疗

A co-activation strategy for enhancing the performance of hematite in photoelectrochemical water oxidation

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Chinese Chemical Letters 2021年第7期32卷 2279-2282页

作者： boyao Xie Xingming Ning Shuoming Wei Jia Liu Jimei Zhang Xiaoquan Lu Tianjin Key Laboratory of Molecular Optoelectronic Science Department of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China State Key Laboratory of Separation Membranes and Membrane Processes School of Chemistry and Chemical EngineeringTiangong UniversityTianjin 300387China

Hematite(α-Fe_(2)O_(3))is a promising photoanode for photoelectrochemical(PEC)water ***,the severe charge recombination and sluggish water oxidation kinetics extremely limit its use in photohydrogen ***,a co-activation strategy is proposed,namely through phosphorus(P)doping and the loading of CoAl-layered double hydroxides(CoAl-LDHs)***,the integrated system,CoAl-LDHs/P-Fe_(2)O_(3) photoanode,exhibits an outstanding photocurrent density of 1.56 mA/cm^(2) at 1.23 V(*** hydrogen electrode,RHE),under AM 1.5 G,which is 2.6 times of pureα-Fe_(2)O_(3).Systematic studies reveal that the remarkable PEC performance is attributed to accelerated surface OER kinetics and enhanced carrier separation *** work provides a feasible strategy to enhance the PEC performance of hematite photoanodes.

关键词： Photoelectrochemical Phosphorus doping Charge separation CoAl-LDHs Hematite

卡介苗胞壁蛋白诱导THP-1细胞IL-12mRNA表达

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四川生理科学杂志 2003年第1期25卷 24-26页

作者：唐琼孔祥丽杨云霞冯云吴琦王伯瑶四川大学华西医学中心基础与法医学院感染免疫研究室药理教研室成都610041 四川大学华西医学中心基础与法医学院成都610041

目的 :研究卡介苗 (BCG)能否诱导人单核白细胞系细胞THP 1、IL 1 2P40基因表达 ,并鉴定其胞壁蛋白的活性组份。方法 :应用逆转录聚合酶链反应 (RT PCR)法检测THP 1细胞IL 1 2P40mRNA的表达 ;采用超声破碎细胞、蔗糖密度梯度离心、Sephad... 详细信息

目的 :研究卡介苗 (BCG)能否诱导人单核白细胞系细胞THP 1、IL 1 2P40基因表达 ,并鉴定其胞壁蛋白的活性组份。方法 :应用逆转录聚合酶链反应 (RT PCR)法检测THP 1细胞IL 1 2P40mRNA的表达 ;采用超声破碎细胞、蔗糖密度梯度离心、SephadexG 1 5 0柱层析等方法分离卡介苗胞壁蛋白质组份。结果 :卡介苗胞壁蛋白SephadexG 1 5 0柱层析所得组分中 ,分子量范围约 2 1～ 2 9kD的组份诱导THP 1细胞IL 1 2P40mR NA的表达增强。结论 :结果显示BCG胞壁蛋白可刺激白细胞IL 1 2P40基因的表达。

关键词：卡介苗胞壁蛋白诱导 THP—l细胞 IL-l2 mRNA 表达