检索结果-南通市图书馆

Effects of tree size and organ age on variations in carbon,nitrogen,and phosphorus stoichiometry in Pinus koraiensis

引用

Journal of Forestry Research 2024年第3期35卷 155-165页

作者： Yanjun wang Guangze jin Zhili Liu Center for Ecological Research Northeast Forestry UniversityHarbin 150040People's Republic of China Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education Northeast Forestry UniversityHarbin 150040People's Republic of China Northeast Asia Biodiversity Research Center Northeast Forestry UniversityHarbin 150040People's Republic of China

Carbon(C),nitrogen(N),and phosphorus(P)are of fundamental importance for growth and nutrient dynamics within plant organs and deserve more attention at regional to global ***,our knowledge of how these nutrients vary with tree size,organ age,or root order at the individual level remains *** determined C,N,and P contents and their stoichiometric ratios(i.e.,nutrient traits)in needles,branches,and fine roots at different organ ages(0-3-year-old needles and branches)and root orders(1st-4th order roots)from 64 Pinus koraiensis of varying size(Diameter at breast height ranged from 0.3 to 100 cm)in northeast *** factors were also *** results show that nutrient traits were regulated by tree size,organ age,or root order rather than soil *** a whole-plant level,nutrient traits decreased in needles and fine roots but increased in branches with tree *** the organ level,age or root order had a negative effect on C,N,and P and a positive effect on stoichiometric *** results demonstrate that nutrient variations are closely related to organ-specific functions and ecophysiological processes at an individual *** is suggested that the nutrient acquisition strategy by younger trees and organ fractions with higher nutrient content is for ***,nutrient storage strategy in older trees and organ fractions are mainly for steady *** results clarified the nutrient utilization strategies during tree and organ ontogeny and suggest that tree size and organ age or root order should be simultaneously considered to understand the complexities of nutrient variations.

关键词： Tree size Organ age(or root order) Carbon(C) Nitrogen(N) Phosphorus(P) Pinus koraiensis

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Pb induced dislocation defects of PtCo systems: Strain-triggered oxygen reduction reaction for PEMFC

引用

Nano Research 2024年第4期17卷 2462-2472页

作者： Chun jin Qiheng wang jingjun Liu Beijing Key Laboratory of Electrochemical Process and Technology for Materials Beijing 100029China Beijing University of Chemical Technology Beijing 100029China

Design and development of advanced electrocatalysts with high performance and low Pt consumption are crucial for reducing the kinetic energy barrier of the cathode oxygen reduction reaction(ORR)and improving the efficiency of proton exchange membrane fuel cells(PEMFC).In this study,we demonstrate a Pb-modulated PtCo system for efficient ORR,in which the inclusion of Pb in ternary alloys induces dislocation defects due to the significant difference in atomic ***-PtCoPb was confirmed to exhibit significantly higher ORR activity and stability in acidic *** practical PEMFC applications,it outperforms the corresponding commercial Pt/C with a mass activity of 0.58 A·mgPt^(-1),making it a promising alternative to state-of-the-art Pt-based *** combination of experimental results and density functional theory(DFT)calculations offers valuable atomic-level insights into the dislocation *** with a larger atomic radius is located in the lattice stretching region below the dislocation slip plane,forming a structure similar to a Cottrell atmosphere,which reduces the dislocation energy and puts the system in a lower energy *** Cottrell atmosphere pins the dislocation structure and stabilizes the ternary *** adjusting the amount of added Pb,a moderate level of dislocation density induces a tuned strain effect,thereby enhancing the electrocatalytic mechanism by optimizing the electronic structure of the alloy surface and the adsorption and desorption of oxygen *** work provides valuable insights into the design and development of lattice dislocation defect structures to trigger strain effects for improving ORR performance.

关键词： dislocation defect strain effect Pb-modulated oxygen reduction reaction

来源：

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

Metal-based inorganic nanocrystals for biological sonodynamic therapy applications:recent progress and perspectives

引用

Rare Metals 2024年第2期43卷 413-430页

作者： dong wang Jia-Tao Zhang Institute of Medical-Industrial Integration Beijing Key Laboratory of Structurally Controllable Advanced Functional Materials and Green ApplicationsSchool of Materials Science and EngineeringBeijing Institute of TechnologyBeijing100081China Key Laboratory of Medical Molecule Science and Pharmaceutics Engineering Ministry of Industry and Information TechnologySchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing100081China

With the fast development of technology for the treatment of tumor and bacteria,photo-therapeutic strate-gies emerge as a kind of highly effective and common treatment,but the low tissue penetration depth of light limits their *** therapy(SDT),as an efficient and non-invasive treatment,attracts more people's attention due to the inherent property of high tissue *** soft tissue penetration depth of ultrasound(US)can even reach more than 10 cm,which has great advantage over that of ***,many sonosensitizers are studied and applied to SDT-based ***-based inorganic nanocrystals are able to generate more reactive oxygen species(ROS)due to the special composition and band *** representative achievements and the specific functions of the nanocrystals sonosensitizers are summarized in this work,and the relationship of structure/composition-SDT performance and the internally regulated composite is ***-gistic effects of SDT in combination with other therapeutic modalities are mainly *** the same time,the critical and potential issues and future perspectives are addressed.

关键词： Metal-based inorganic nanocrystals Sonodynamic therapy(SDT) Tumor treatment Antibacteria

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Colonoscopy-assisted removal of an impaction foreign body at the rectosigmoid junction: A case report

引用

World Journal of Clinical Cases 2024年第11期12卷 1990-1995页

作者： Peng-Fei Zhou jin-Gen Lu Jia-dong Zhang Jia-Wen wang Department of Anorectal Surgery Longhua Hospital Shanghai University of Traditional Chinese MedicineShanghai 200000China

BACKGROUND When an anorectal foreign body is found,its composition and shape should be evaluated,and a timely and effective treatment plan should be developed based on the patient's symptoms to avoid serious complications such as intestinal perforation caused by displacement of the foreign *** SUMMARY A 54-year-old male was admitted to our outpatient clinic on June 3,2023,due to a rectal foreign body that had been embedded for more than 24 *** patient reported using a glass electrode tube to assist in the recovery of prolapsed hemorrhoids,however,the electrode tube was inadvertently inserted into the anus and could not be removed by the *** hospitalization,the patient underwent surgery,and the foreign body was dragged into the rectum with the aid of *** anus was dilated with a comb-type pulling hook and an anal fistula pulling hook to widen the anus and remove the foreign body,and the local anal symptoms were then relieved with topical *** patient was allowed to eat and drink,and an entire abdominal Computed tomography(CT)and colonoscopy were reviewed 3 d after *** revealed no foreign body residue and colonoscopy showed no metal or other residues in the colon and rectum,and no apparent intestinal tract *** The timeliness and rationality of the surgical and therapeutic options for this patient were based on a literature review of the clinical signs and conceivable conditions in such *** type,material and the potential risks of rectal foreign bodies should be considered.

关键词： Foreign body impaction Surgical therapy Rectum-sigmoid colon Colonoscopy Case report

来源：

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

Mechanisms of fracture propagation from multi-cluster using a phase field based HMD coupling model in fractured reservoir

引用

Petroleum Science 2024年第3期21卷 1829-1851页

作者： Yun-jin wang Bo wang Hang Su Tu Chang Ren-Cheng dong Li-Zhe Li Wei-Yu Tang Ting-Xue Jiang Fu-Jian Zhou State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBejing2249China China University of Petroleum-Beijing at Karamay Karamay834000XinjiangChina China National Oil and Gas Exploration and Development Corporation Ltd. Beijing100034China University of Texas at Austin United States SINOPEC Research Institute of Petroleum Engineering Beijing100101China

Natural fractures(NFs)are common in shale and tight reservoirs,where staged multi-cluster fracturing of horizontal wells is a prevalent technique for reservoir *** NFs and stress interference are recognized as significant factors affecting hydraulic fracture(HF)propagation,the combined influence of these factors remains poorly *** address this knowledge gap,a novel coupled hydromechanical-damage(HMD)model based on the phase field method is developed to investigate the propagation of multi-cluster HFs in fractured *** comprehensive energy functional and control functions are established,while incorporating dynamic fluid distribution between multiple perforation clusters and refined changes in rock mechanical parameters during hydraulic *** HMD coupled multi-cluster HF propagation model investigates various scenarios,including single HF and single NF,reservoir heterogeneity,single HF and NF clusters,and multi-cluster HFs with NF *** results show that the HMD coupling model can accurately capture the impact of approach angle(θ),stress difference and cementation strength on the interaction of HF and *** criterion of the open and cross zones is not *** NF angle(a)is not a decisive parameter to discriminate the *** to the relationship between approach angle(θ)and NF angle(a),the contact relationship of HF can be divided into three categories(θ=a,θa).The connected NF can increase the complexity of HF by inducing it to form branch fracture,resulting in a fractal dimension of HF as high as2.1280 at angles of±45°.Inter-fracture interference from the heel to the toe of HF shows the phenomenon of no,strong and weak ***,under the influence of NFs,distant HFs from the injection can become dominant ***,as a gradually increases,inter-fracture stress interference becomes the primary factor influencing HF propagation,gradually superseding the dominance of NF

关键词： HMD coupling Phase field Natural fracture Flow distribution Hydraulic fracturing Inter-fracture interference

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Electrochemical reconstruction: a new perspective on Sn metal-organic complex microbelts as robust anode for lithium storage

引用

Rare Metals 2024年第1期43卷 76-86页

作者： jin-Ke Shen Nai-Teng Wu Li-Yuan wang Gang Jiang dong-Lei Guo jin Li Gui-Long Liu Hong-Yu Mi Huan Pang Xian-Ming Liu Key Laboratory of Function-oriented Porous Materials of Henan Province College of Chemistry and Chemical EngineeringLuoyang Normal UniversityLuoyang 471934China State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources School of Chemical Engineering and TechnologyXinjiang UniversityUrumqi 830046China School of Chemistry and Chemical Engineering Institute for Innovative Materials and EnergyYangzhou UniversityYangzhou 225009JiangsuChina

Tin-based materials with high theoretical capacity and suitable working voltage are ideal anode materials for lithium-ion batteries(LIBs). However, to overcome their shortcomings(volume expansion and inferior stability), the preparation processes are usually complicated and expensive. Herein, a tin-based metal-organic complex(tin 1,2-benzenedicarboxylic acid, Sn-BDC)with one-dimensional microbelt morphology is synthesized by a facile, rapid and low-cost co-precipitation method, and served as anode material for LIBs without any post-treatment. Sn-BDC exhibits a high reversible capacity with609/440 m Ah·g^(-1) at 50/2000 m A·g^(-1), and robust cycling stability of 856 m Ah·g^(-1) after 200 cycles at 200 m A·g^(-1),which are obviously superior to that of the Sn Ox/C counterparts. Moreover, an electrochemical reconstruction perspective on the lithium storage mechanism of Sn-BDC is proposed by systematic ex-situ characterizations. The reconstructed SnO_(2) replaces Sn-BDC and becomes the active material in the subsequent cycles. As the by-product of the lithiation reaction, the formed Li-based metal-organic complex(Li-BDC, wrapped around the reconstructed SnO_(2)) plays an important role in alleviating volume expansion and accelerating the charge transfer *** work is beneficial to design and construct the new electrode materials based on the electrochemical reconstruction for advanced LIBs.

关键词： Electrochemical reconstruction Metal-organic complex Anode Lithium storage mechanism Lithium-ion batteries

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Multi-modal visual tracking:Review and experimental comparison

引用

Computational Visual Media 2024年第2期10卷 193-214页

作者： Pengyu Zhang dong wang Huchuan Lu Faculty of Electronic Information and Electrical Engineering Dalian University of TechnologyDalian 116024Chin

Visual object tracking has been drawing increasing attention in recent years,as a fundamental task in computer *** extend the range of tracking applications,researchers have been introducing information from multiple modalities to handle specific scenes,with promising research prospects for emerging methods and *** provide a thorough review of multi-modal tracking,different aspects of multi-modal tracking algorithms are summarized under a unified taxonomy,with specific focus on visibledepth(RGB-D)and visible-thermal(RGB-T)***,a detailed description of the related benchmarks and challenges is *** experiments were conducted to analyze the effectiveness of trackers on five datasets:PTB,VOT19-RGBD,GTOT,RGBT234,and ***,various future directions,including model design and dataset construction,are discussed from different perspectives for further research.

关键词： visual tracking object tracking multi-modal fusion RGB-T tracking RGB-D trackin

来源：

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

Numerical Investigations on the Resonance Errors of Multiscale Discontinuous Galerkin Methods for One-Dimensional Stationary Schrödinger Equation

引用

Communications on Applied Mathematics and Computation 2024年第1期6卷 311-324页

作者： Bo dong Wei wang Department of Mathematics University of Massachusetts DartmouthNorth DartmouthMA02747USA Department of Mathematics and Statistics Florida International UniversityMiamiFL33199USA

In this paper,numerical experiments are carried out to investigate the impact of penalty parameters in the numerical traces on the resonance errors of high-order multiscale discontinuous Galerkin(DG)methods(dong et *** J Sci Comput 66:321–345,2016;dong and wang in J Comput Appl Math 380:1–11,2020)for a one-dimensional stationary Schrödinger *** work showed that penalty parameters were required to be positive in error analysis,but the methods with zero penalty parameters worked fine in numerical simulations on coarse *** this work,by performing extensive numerical experiments,we discover that zero penalty parameters lead to resonance errors in the multiscale DG methods,and taking positive penalty parameters can effectively reduce resonance errors and make the matrix in the global linear system have better condition numbers.

关键词： Discontinuous Galerkin(DG)method Multiscale method Resonance errors One-dimensional Schrödinger equation

来源：

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

High-Efficiency Wideband Transmitarray Antenna Using Polarization-Rotating Elements with Parasitic Stubs

引用

Chinese Journal of Electronics 2024年第2期33卷 496-503页

作者： Xi wang Yuandan dong University of Electronic Science and Technology of China

A high-efficiency polarization-rotating transmitarray antenna(TA) using wideband elements is proposed for millimeter-wave applications. The polarization-rotating element consists of three metallic layers and two substrates. Orthogonal polarizers are employed on the top and bottom of the element. And the split ring with a parasitic stub on the middle layer is symmetric about the diagonal, performing the polarization rotation and phase compensation simultaneously. A parasitic stub is designed to decrease transmission loss and broaden the bandwidth. The periodicity of the element is only 1/4 wavelength at 30 GHz. A prototype TA with 28 × 28 elements is designed, fabricated, and measured. The measured peak gain reaches 27.5 d Bi at 37.8 GHz. The 1-d B gain drop bandwidth is 30.8–40 GHz(26.0%).The aperture efficiency reaches as high as 71% at 31.5 GHz. Within the bandwidth of 26.5–38.8 GHz(37.7%), the aperture efficiency is higher than 50%. The proposed polarization-rotating TA features wide bandwidth and high efficiency, demonstrating great application potential for 5G millimeter-wave communication.

关键词： Wavelength measurement Transmitting antennas Prototypes Apertures Gain measurement Propagation losses Broadband antennas

来源：

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Dynamic Event-Triggered Quadratic Nonfragile Filtering for Non-Gaussian Systems:Tackling Multiplicative Noises and Missing Measurements

引用

IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1127-1138页

作者： Shaoying wang Zidong wang Hongli dong Yun Chen Guoping Lu College of Science Shandong University of AeronauticsBinzhou 256603China College of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590 Department of Computer Science Brunel University LondonUxbridge UB83PHUK Artificial Intelligence Energy Research Institute Northeast Petroleum UniversityDaqing 163318 Heilongjiang Provincial Key Laboratory of Networking and Intelligent Control Northeast Petroleum UniversityDaqing 163318China School of Automation Hangzhou Dianzi UniversityHangzhou 310018China School of Electrical Engineering Nantong UniversityNantong 226019China

This paper focuses on the quadratic nonfragile filtering problem for linear non-Gaussian systems under multiplicative noises,multiple missing measurements as well as the dynamic event-triggered transmission *** multiple missing measurements are characterized through random variables that obey some given probability distributions,and thresholds of the dynamic event-triggered scheme can be adjusted dynamically via an auxiliary *** attention is concentrated on designing a dynamic event-triggered quadratic nonfragile filter in the well-known minimum-variance *** this end,the original system is first augmented by stacking its state/measurement vectors together with second-order Kronecker powers,thus the original design issue is reformulated as that of the augmented ***,we analyze statistical properties of augmented noises as well as high-order moments of certain random *** the aid of two well-defined matrix difference equations,we not only obtain upper bounds on filtering error covariances,but also minimize those bounds via carefully designing gain ***,an example is presented to explain the effectiveness of this newly established quadratic filtering algorithm.

关键词： filtering quadratic bounds

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：