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Simultaneous quantification of trace heavy metals in mushrooms using a three-dimensional highly reduced graphene oxide/Fe_(3)O_(4)nanocomposite-based electrochemical sensor
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作者 Yiming Tian Pingsheng Zhong +2 位作者 Kai Zhou Lufei Zheng Jiali Ren 《Food Science and Human Wellness》 2025年第6期2268-2277,共10页
The accumulation of heavy metals in mushrooms has presented a significant risk to human health,underscoring the importance of devising a portable and cost-effective method for detecting heavy metals.Thus,we have devel... The accumulation of heavy metals in mushrooms has presented a significant risk to human health,underscoring the importance of devising a portable and cost-effective method for detecting heavy metals.Thus,we have developed an electrochemical sensor based on 3-dimensional highly reduced graphene oxide(3D-HRGO)in conjunction with Fe_(3)O_(4)nanoparticles,enabling the simultaneous quantification of Cd^(2+),Pb^(2+),Cu^(2+),and Hg^(2+).The 3D-HRGO/Fe_(3)O_(4)nano-particles material prepared in this study was characterized and confirmed by multiple techniques,then dispersed in a simple and environmental dispersant,consist of 75%ethanol and 0.1%Nafion,and coating on a glass carbon electrode(GCE)to preparing a 3D-HRGO/Fe_(3)O_(4)/GCE sensor.The limit of detection(LOD)of 3D-HRGO/Fe_(3)O_(4)/GCE sensor for Cd^(2+),Pb^(2+),Cu^(2+),and Hg^(2+)in simultaneous detection were 0.2,0.6,0.6,and 0.9μg/L,respectively.The sensor demonstrates exceptional stability,reproducibility,anti-interference,and recovery rate.Furthermore,the electrochemical sensor was employed to detect heavy metals in actual mushrooms and validated through conventional methodologies.This study represents the pioneering utilization of 3D-HRGO/Fe_(3)O_(4)as a foundational material for an electrochemical sensor capable of simultaneous detection of multiple metals,thereby advancing the progress of on-site and expeditious detection techniques. 展开更多
关键词 Electrochemical sensor 3D-HRGO/Fe_(3)O_(4)nanocomposite MUSHROOMS Heavy metals Rapid and simultaneous detection
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Three-Dimensional Ocean Sensor Networks:A Survey 被引量:21
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作者 WANG Yu LIU Yingjian GUO Zhongwen 《Journal of Ocean University of China》 SCIE CAS 2012年第4期436-450,共15页
The past decade has seen a growing interest in ocean sensor networks because of their wide applications in marine research,oceanography,ocean monitoring,offshore exploration,and defense or homeland security.Ocean sens... The past decade has seen a growing interest in ocean sensor networks because of their wide applications in marine research,oceanography,ocean monitoring,offshore exploration,and defense or homeland security.Ocean sensor networks are generally formed with various ocean sensors,autonomous underwater vehicles,surface stations,and research vessels.To make ocean sensor network applications viable,efficient communication among all devices and components is crucial.Due to the unique characteristics of underwater acoustic channels and the complex deployment environment in three dimensional(3D) ocean spaces,new efficient and reliable communication and networking protocols are needed in design of ocean sensor networks.In this paper,we aim to provide an overview of the most recent advances in network design principles for 3D ocean sensor networks,with focuses on deployment,localization,topology design,and position-based routing in 3D ocean spaces. 展开更多
关键词 ocean sensor networks underwater sensor networks three-dimensional sensor networks ocean applications 3D de-ployment topology design LOCALIZATION position-based routing
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Three-dimensional graphene and its composite for gas sensors 被引量:5
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作者 Meng Hao Wen Zeng +1 位作者 Yan-Qiong Li Zhong-Chang Wang 《Rare Metals》 SCIE EI CAS CSCD 2021年第6期1494-1514,共21页
As a two-dimensional(2D)material,graphene shows excellent advantages in the field of gas sensors due to its inherent large specific surface area and unique electrical properties.However,in the practical application of... As a two-dimensional(2D)material,graphene shows excellent advantages in the field of gas sensors due to its inherent large specific surface area and unique electrical properties.However,in the practical application of gas detection,graphene sheet is easy to form irreversible agglomeration and has some limitations such as low sensitivity,long response time and slow recovery speed,which greatly reduce its gas sensing performance.As a gas sensing material,three-dimensional(3D)porous graphene has been extensively studied in recent years owing to its larger specific surface area and stable structure.In order to synthesize graphene with different three-dimensional structures,many methods have been developed.Herein,the synthesis and assembly of three-dimensional graphene and its composites were reviewed,with emphasis on the application of three-dimensional graphene and its composites in the field of gas sensors.The challenges and development prospects of three-dimensional graphene materials in the application of gas sensors were briefly described. 展开更多
关键词 three-dimensional graphene Gas sensor Sensitivity Composites material
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Three-dimensional hierarchical CuO gas sensor modified by Au nanoparticles 被引量:2
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作者 Qi Lei Hairong Li +3 位作者 Huan Zhang Jianan Wang Wenhao Fan Lina Cai 《Journal of Semiconductors》 EI CAS CSCD 2019年第2期17-23,共7页
The three-dimensional hierarchical CuO and Au nanoparticles were synthesized by the hydrothermal method, respectively. The hierarchical CuO and the Au nanoparticles samples were characterized by X-ray diffraction and ... The three-dimensional hierarchical CuO and Au nanoparticles were synthesized by the hydrothermal method, respectively. The hierarchical CuO and the Au nanoparticles samples were characterized by X-ray diffraction and scanning electronic microscope, respectively. The as-synthesized CuO was assembled regularly from the nanosheets with thickness of 100 nm. The size of Au nanoparticles ranged from 50 to 200 nm. The hierarchical CuO gas sensors modified by different concentration of gold were fabricated. All the Au-loaded CuO gas sensors enhanced the response to ethanol and xylene while reducing the response to methanol, acetone, and formaldehyde. The results indicate that the Au nanoparticles prepared with PVP as surfactant can improve the selectivity of CuO gas sensors to ethanol gas for other common organic volatile gases. The improvement of gas sensing is mainly attributed to the different catalytic efficiency of the Au nanoparticles for different reactions. Meanwhile, the related mechanisms are discussed. 展开更多
关键词 CUO AU NANOPARTICLE gas sensor SELECTIVITY
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Global Mapping of Three-Dimensional Urban Structures Reveals Escalating Utilization in the Vertical Dimension and Pronounced Building Space Inequality 被引量:1
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作者 Xiaoping Liu Xinxin Wu +6 位作者 Xuecao Li Xiaocong Xu Weilin Liao Limin Jiao Zhenzhong Zeng Guangzhao Chen Xia Li 《Engineering》 2025年第4期86-99,共14页
Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significan... Three-dimensional(3D)urban structures play a critical role in informing climate mitigation strategies aimed at the built environment and facilitating sustainable urban development.Regrettably,there exists a significant gap in detailed and consistent data on 3D building space structures with global coverage due to the challenges inherent in the data collection and model calibration processes.In this study,we constructed a global urban structure(GUS-3D)dataset,including building volume,height,and footprint information,at a 500 m spatial resolution using extensive satellite observation products and numerous reference building samples.Our analysis indicated that the total volume of buildings worldwide in2015 exceeded 1×10^(12)m^(3).Over the 1985 to 2015 period,we observed a slight increase in the magnitude of 3D building volume growth(i.e.,it increased from 166.02 km3 during the 1985–2000 period to 175.08km3 during the 2000–2015 period),while the expansion magnitudes of the two-dimensional(2D)building footprint(22.51×10^(3) vs 13.29×10^(3)km^(2))and urban extent(157×10^(3) vs 133.8×10^(3)km^(2))notably decreased.This trend highlights the significant increase in intensive vertical utilization of urban land.Furthermore,we identified significant heterogeneity in building space provision and inequality across cities worldwide.This inequality is particularly pronounced in many populous Asian cities,which has been overlooked in previous studies on economic inequality.The GUS-3D dataset shows great potential to deepen our understanding of the urban environment and creates new horizons for numerous 3D urban studies. 展开更多
关键词 three-dimensional Global mapping Building volume Building height Building space inequality
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The influence of temperature on flow-induced forces on quartz-crystal-microbalance sensors in a Chinese liquor identification electronic-nose: three-dimensional computational fluid dynamics simulation and analysis 被引量:2
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作者 Qiang LI Yu GU Huatao WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2019年第9期1301-1312,共12页
An electronic-nose is developed based on eight quartz-crystal-microbalance (QCM) gas sensors in a sensor box, and is used to detect Chinese liquors at room temperature. Each sensor is a highly-accurate and highly-sens... An electronic-nose is developed based on eight quartz-crystal-microbalance (QCM) gas sensors in a sensor box, and is used to detect Chinese liquors at room temperature. Each sensor is a highly-accurate and highly-sensitive oscillator that has experienced airflow disturbances under the condition of varying room temperatures due to unstable flow-induced forces on the sensors surfaces. The three-dimensional (3D) nature of the airflow inside the sensor box and the interactions of the airflow on the sensors surfaces at different temperatures are studied by computational fluid dynamics (CFD) tools. Higher simulation accuracy is achieved by optimizing meshes, meshing the computational domain using a fine unstructural tetrahedron mesh. An optimum temperature, 30 ℃, is obtained by analyzing the distributions of velocity streamlines and the static pressure, as well as the flow-induced forces over time, all of which may be used to improve the identification accuracy of the electronic-nose for achieving stable and repeatable signals by removing the influence of temperature. 展开更多
关键词 computational fluid dynamics (CFD) TEMPERATURE quartz-crystalmicrobalance (QCM) gas sensor ELECTRONIC NOSE IDENTIFICATION accuracy
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Three-dimensional line-of-sight-angle-constrained leader-following cooperative interception guidance law with prespecified impact time 被引量:2
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作者 Hao YOU Xinlong CHANG Jiufen ZHAO 《Chinese Journal of Aeronautics》 2025年第1期491-506,共16页
To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D lea... To address the problem of multi-missile cooperative interception against maneuvering targets at a prespecified impact time and desired Line-of-Sight(LOS)angles in ThreeDimensional(3D)space,this paper proposes a 3D leader-following cooperative interception guidance law.First,in the LOS direction of the leader,an impact time-controlled guidance law is derived based on the fixed-time stability theory,which enables the leader to complete the interception task at a prespecified impact time.Next,in the LOS direction of the followers,by introducing a time consensus tracking error function,a fixed-time consensus tracking guidance law is investigated to guarantee the consensus tracking convergence of the time-to-go.Then,in the direction normal to the LOS,by combining the designed global integral sliding mode surface and the second-order Sliding Mode Control(SMC)theory,an innovative 3D LOS-angle-constrained interception guidance law is developed,which eliminates the reaching phase in the traditional sliding mode guidance laws and effectively saves energy consumption.Moreover,it effectively suppresses the chattering phenomenon while avoiding the singularity issue,and compensates for unknown interference caused by target maneuvering online,making it convenient for practical engineering applications.Finally,theoretical proof analysis and multiple sets of numerical simulation results verify the effectiveness,superiority,and robustness of the investigated guidance law. 展开更多
关键词 three-dimensional cooperative interception Leader-following missiles Prespecified impact time LOS-angle-constrained Fixed-time stability Global integral sliding mode
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Three-dimensional models:from cell culture to Patient-Derived Organoid and its application to future liposarcoma research
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作者 SAYUMI TAHARA SYDNEY RENTSCH +4 位作者 FERNANDA COSTAS CASAL DE FARIA PATRICIA SARCHET ROMA KARNA FEDERICA CALORE RAPHAEL E.POLLOCK 《Oncology Research》 SCIE 2025年第1期1-13,共13页
Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma ... Liposarcoma is one of the most common soft tissue sarcomas,however,its occurrence rate is still rare compared to other cancers.Due to its rarity,in vitro experiments are an essential approach to elucidate liposarcoma pathobiology.Conventional cell culture-based research(2D cell culture)is still playing a pivotal role,while several shortcomings have been recently under discussion.In vivo,mouse models are usually adopted for pre-clinical analyses with expectations to overcome the issues of 2D cell culture.However,they do not fully recapitulate human dedifferentiated liposarcoma(DDLPS)characteristics.Therefore,three-dimensional(3D)culture systems have been the recent research focus in the cell biology field with the expectation to overcome at the same time the disadvantages of 2D cell culture and in vivo animal models and fill in the gap between them.Given the liposarcoma rarity,we believe that 3D cell culture techniques,including 3D cell cultures/co-cultures,and Patient-Derived tumor Organoids(PDOs),represent a promising approach to facilitate liposarcoma investigation and elucidate its molecular mechanisms and effective therapy development.In this review,we first provide a general overview of 3D cell cultures compared to 2D cell cultures.We then focus on one of the recent 3D cell culture applications,Patient-Derived Organoids(PDOs),summarizing and discussing several PDO methodologies.Finally,we discuss the current and future applications of PDOs to sarcoma,particularly in the field of liposarcoma. 展开更多
关键词 Cell culture LIPOSARCOMA Patient-Derived Organoid(PDO) SPHEROID three-dimensional(3D)cell culture
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Glasses-free three-dimensional laparoscopic systems in oncologic surgery:Innovation or equivalence?
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作者 Gustavo Eder González Alvarez Christian Ramírez Sánchez +3 位作者 Melissa Martínez Nieto Mario A Alarcón-Sánchez Juan JoséVarela-Hernández Sarah M LomelíMartínez 《World Journal of Gastrointestinal Surgery》 2025年第11期6-11,共6页
The development of minimally invasive surgery has transformed the management of gastrointestinal cancer.Notably,three-dimensional visualization systems have increased surgical precision.This editorial discusses a rece... The development of minimally invasive surgery has transformed the management of gastrointestinal cancer.Notably,three-dimensional visualization systems have increased surgical precision.This editorial discusses a recent study by Shen and Zhang,which compared the clinical applications of naked-eye threedimensional laparoscopic systems vs traditional optical systems in radical surgery for gastric and colorectal cancer.Both systems appeared to yield comparable surgical and oncological outcomes in terms of safety parameters,operating times,and quality of lymph node dissection.However,the spectacle-free system’s technical and logistical limitations hindered its effects on the surgical team’s overall competency.This editorial examines the authors’findings within the broader context of the evolution of oncologic laparoscopy,discusses the relevance of the results in light of the current literature,and proposes future research directions focused on multicenter validation,comprehensive ergonomic analysis,and technological advancements aimed at enhancing intraoperative collaboration.As technology continues to evolve,clinical implementation of new methods must be supported by robust scientific evidence and standardized criteria,to ensure tangible improvements in efficiency,safety,and oncologic outcomes. 展开更多
关键词 Autostereoscopic three-dimensional technology Laparoscopic surgery three-dimensional laparoscopy Twodimensional laparoscopy Oncologic surgery
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A Three-Dimensional Range-Free Localization Algorithm Based on Mobile Beacons for Wireless Sensor Networks 被引量:3
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作者 GUERRERO E ALVAREZ J RIVERO L 《Computer Aided Drafting,Design and Manufacturing》 2010年第1期83-92,共10页
In wireless sensor networks (WSNs) the position information of individual nodes is a matter of vital importance because allows the implementation of necessary network functions such as routing, querying and other ap... In wireless sensor networks (WSNs) the position information of individual nodes is a matter of vital importance because allows the implementation of necessary network functions such as routing, querying and other applications. The objective of this paper is to propose an algorithm of three-dimensional distributed range-free localization for WSNs, using a mobile beacon (MB) equipped with a rotary and tilting directional antenna. This algorithm, denominated as the three-dimensional azimuthally defined area localization algorithm (3D- ADAL), is executed in each sensor node and is based only on the analysis of the information received from the MB, therefore is energy efficient and contributes to extend the lifetime of the sensor network. Additionally the proposed algorithm has the advantage of being simple and economical. The simulation results show that the proposed algorithm is a practical, effective and accurate method for a three-dimensional location of sensor nodes in a WSN. 展开更多
关键词 3D localization wireless sensor network mobile beacon directional antenna
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Investigation into the degradation of 2,4,6-trichlorophenol utilizing a three-dimensional electrocatalytic reactor filled with fluorine-doped copper-carbon particle electrodes
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作者 Hongrui Zhang Wenyu Huang +4 位作者 Hainong Song Hanhui Yan Jia Zhang Fang Zhong Huilan Li 《Journal of Environmental Sciences》 2025年第9期701-719,共19页
The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated cata... The three-dimensional particle electrode system exhibits significant potential for application in the treatment of wastewater.Nonetheless,the advancement of effective granular electrodes characterized by elevated catalytic activity and minimal energy consumption continues to pose a significant challenge.In this research,Fluorine-doped copper-carbon(F/Cu-GAC)particle electrodes were effectively synthesized through an impregnationcalcination technique,utilizing granular activated carbon as the carrier and fluorinedoped modified copper oxides as the catalytic agents.The particle electrodes were subsequently utilized to promote the degradation of 2,4,6-trichlorophenol(2,4,6-TCP)in a threedimensional electrocatalytic reactor(3DER).The F/Cu-GAC particle electrodes were polarized under the action of electric field,which promoted the heterogeneous Fenton-like reaction in which H2O2 generated by two-electron oxygen reduction reaction(2e-ORR)of O_(2) was catalytically decomposed to·OH.The 3DER equipped with F/Cu-GAC particle electrodes showed 100%removal of 2,4,6-TCP and 79.24%removal of TOC with a specific energy consumption(EC)of approximately 0.019 kWh/g·COD after 2 h of operation.The F/Cu-GAC particle electrodes exhibited an overpotential of 0.38 V and an electrochemically active surface area(ECSA)of 715 cm^(2),as determined through linear sweep voltammetry(LSV)and cyclic voltammetry(CV)assessments.These findings suggest a high level of electrocatalytic performance.Furthermore,the catalytic mechanism of the 3DER equipped with F/Cu-GAC particle electrodes was elucidated through the application of X-ray photoelectron spectroscopy(XPS),electron spin resonance(ESR),and active species capture experiments.This investigation offers a novel approach for the effective degradation of 2,4,6-TCP. 展开更多
关键词 2 4 6-TRICHLOROPHENOL Heterogeneous Fenton-like process three-dimensional electrocatalytic reactor three-dimensional particle electrode system Fluorine-doped copper-carbon particle electrodes
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A Review of Three-Dimensional Research on Urban Recreation Space Based on CiteSpace
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作者 LIU Yongli 《Journal of Landscape Research》 2025年第1期30-34,共5页
In this study,CiteSpace software is used to carry out visual analysis on the three-dimensional research literature on urban recreation space from the perspective of compact city theory in the past 20 years,exploring t... In this study,CiteSpace software is used to carry out visual analysis on the three-dimensional research literature on urban recreation space from the perspective of compact city theory in the past 20 years,exploring the scientific development trend and research hotspots in this field.The results show that the number of published documents shows a fluctuating upward trend,and the significant growth rate reflects the role of policy orientation in promoting the concept of compact city.The co-occurrence analysis of keywords reveals the research hotspots of“compact city”,“recreation space”and“urban park”,while the emergence of new keywords such as“vertical city”and“spatial justice”indicates the new trend of recent research.The cluster analysis and timeline map further show the evolution of research themes,with“compact city”being the largest cluster and having rich connections with other themes such as“urban design”and“urban park”. 展开更多
关键词 Compact city Urban recreation space three-dimensional CITESPACE
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Resection of a ganglioneuroma encasing major blood vessels using three-dimensional laparoscopy combined with organ suspension:A case report
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作者 Guo-Zhen Wu Shen-Zhe Fang +1 位作者 Shi-An Yu Min Yu 《World Journal of Gastrointestinal Surgery》 2025年第8期467-475,共9页
BACKGROUND Ganglioneuroma is a rare,well-differentiated,slow-growing benign tumor of the peripheral nerves,with surgical resection being the only curative treatment.Surgical resection of ganglioneuromas encasing major... BACKGROUND Ganglioneuroma is a rare,well-differentiated,slow-growing benign tumor of the peripheral nerves,with surgical resection being the only curative treatment.Surgical resection of ganglioneuromas encasing major blood vessels remains a substantial clinical challenge.Traditionally,these cases often require open abdominal surgery or combined organ resections,and in some instances,the tumors are considered unresectable.Currently,no reports have described the resection of such tumors via laparoscopy.CASE SUMMARY A 35-year-old woman was admitted to our hospital after the incidental discovery of a retroperitoneal space-occupying lesion.Imaging revealed a mass with the celiac axis and superior mesenteric artery passing through it.A neurogenic tumor was suspected,with ganglioneuroma being the most likely diagnosis.Following comprehensive preoperative preparation,the retroperitoneal tumor was resected using a three-dimensional laparoscopy combined with an organ suspension technique.The surgical approach involved incising the tumor along the vascular axis and conducting meticulous,vascular-preserving tumor excision.The operation lasted approximately 458 minutes,with an estimated blood loss of 50 mL.The patient was discharged on the 8th postoperative day.A transient liver injury occurred after surgery but improved rapidly.After 11 months of postoperative follow-up,no complications or tumor recurrence were observed.CONCLUSION This case illustrates the feasibility of minimally invasive laparoscopic resection for retroperitoneal ganglioneuromas encasing major blood vessels. 展开更多
关键词 Ganglioneuromas Retroperitoneal three-dimensional laparoscopy Organ suspension Case report
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Reconfigurable Three-Dimensional Thermal Dome
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作者 Yuhong Zhou Fubao Yang +5 位作者 Liujun Xu Pengfei Zhuang Dong Wang Xiaoping Ouyang Ying Li Jiping Huang 《Engineering》 2025年第3期236-244,共9页
Thermal metamaterial represents a groundbreaking approach to control heat conduction,and,as a crucial component,thermal invisibility is of utmost importance for heat management.Despite the flourishing development of t... Thermal metamaterial represents a groundbreaking approach to control heat conduction,and,as a crucial component,thermal invisibility is of utmost importance for heat management.Despite the flourishing development of thermal invisibility schemes,they still face two limitations in practical applications.First,objects are typically completely enclosed in traditional cloaks,making them difficult to use and unsuitable for objects with heat sources.Second,although some theoretical proposals have been put forth to change the thermal conductivity of materials to achieve dynamic invisibility,their designs are complex and rigid,making them unsuitable for large-scale use in real threedimensional(3D)spaces.Here,we propose a concept of a thermal dome to achieve 3D invisibility.Our scheme includes an open functional area,greatly enhancing its usability and applicability.It features a reconfigurable structure,constructed with simple isotropic natural materials,making it suitable for dynamic requirements.The performance of our reconfigurable thermal dome has been confirmed through simulations and experiments,consistent with the theory.The introduction of this concept can greatly advance the development of thermal invisibility technology from theory to engineering and provide inspiration for other physical domains,such as direct current electric fields and magnetic fields. 展开更多
关键词 Thermal domes Reconfigurable metamaterials three-dimensional invisibility
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Three-dimensional spectral analysis of gravity waves from airglow observations over Northwest China
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作者 QinZeng Li JiYao Xu +3 位作者 Wei Yuan Xiao Liu YaJun Zhu WeiJun Liu 《Earth and Planetary Physics》 2025年第4期988-994,共7页
The three-dimensional spectral analysis method was applied to airglow data from September 2023 to August 2024 derivedfrom an OH airglow imager located at the Hejing station (42.79°N, 83.73°E) to study the pr... The three-dimensional spectral analysis method was applied to airglow data from September 2023 to August 2024 derivedfrom an OH airglow imager located at the Hejing station (42.79°N, 83.73°E) to study the propagation characteristics of gravity waves(GWs) over Northwest China. We found that obvious seasonal variations occur in the propagation of GWs. In spring, GWs mainlypropagate in the northeast direction. In summer and autumn, GWs mainly propagate in the north direction. However, GWs mainlypropagate in the south direction in winter. The direction of GW propagation in the zonal direction is controlled by the wind-filteringeffect, whereas the north–south meridional direction is mainly determined by the location of the wave source. We found that the averageenergy spectrum exhibits a 10%–20% higher intensity in summer and winter compared with spring and autumn. For the first time, wereport the seasonal variation characteristics of GWs over the inland areas of Northwest China, which is of great significance forunderstanding the regional distribution characteristics of GWs. 展开更多
关键词 AIRGLOW gravity wave three-dimensional spectral analysis seasonal variation
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Three-dimensional internal multiple elimination in complex structures using Marchenko autofocusing theory
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作者 Pei-Nan Bao Ying Shi +2 位作者 Xin-Min Shang Hong-Xian Liang Wei-Hong Wang 《Petroleum Science》 2025年第1期222-233,共12页
Internal multiples are commonly present in seismic data due to variations in velocity or density of subsurface media.They can reduce the signal-to-noise ratio of seismic data and degrade the quality of the image.With ... Internal multiples are commonly present in seismic data due to variations in velocity or density of subsurface media.They can reduce the signal-to-noise ratio of seismic data and degrade the quality of the image.With the development of seismic exploration into deep and ultradeep events,especially those from complex targets in the western region of China,the internal multiple eliminations become increasingly challenging.Currently,three-dimensional(3D)seismic data are primarily used for oil and gas target recognition and drilling.Effectively eliminating internal multiples in 3D seismic data of complex structures and mitigating their adverse effects is crucial for enhancing the success rate of drilling.In this study,we propose an internal multiple prediction algorithm for 3D seismic data in complex structures using the Marchenko autofocusing theory.This method can predict the accurate internal multiples of time difference without an accurate velocity model and the implementation process mainly consists of several steps.Firstly,simulating direct waves with a 3D macroscopic velocity model.Secondly,using direct waves and 3D full seismic acquisition records to obtain the upgoing and down-going Green's functions between the virtual source point and surface.Thirdly,constructing internal multiples of the relevant layers by upgoing and downgoing Green's functions.Finally,utilizing the adaptive matching subtraction method to remove predicted internal multiples from the original data to obtain seismic records without multiples.Compared with the two-dimensional(2D)Marchenko algo-rithm,the performance of the 3D Marchenko algorithm for internal multiple prediction has been significantly enhanced,resulting in higher computational accuracy.Numerical simulation test results indicate that our proposed method can effectively eliminate internal multiples in 3D seismic data,thereby exhibiting important theoretical and industrial application value. 展开更多
关键词 Marchenko Internal multiple elimination Autofocusing three-dimensional seismic data
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Three-dimensional reconstruction under computed tomography and myopectineal orifice measurement under laparoscopy for quality control of inguinal hernia treatment
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作者 Lei Zhang Jing Chen +7 位作者 Yu-Ying Zhang Lei Liu Han-Dan Wang Ya-Fei Zhang Jun Sheng Qiu-Shi Hu Ming-Liang Liu Yi-Lin Yuan 《World Journal of Gastrointestinal Endoscopy》 2025年第3期50-59,共10页
BACKGROUND Inguinal hernias are common after surgery.Tension-free repair is widely accepted as the main method for managing inguinal hernias.Adequate exposure,coverage,and repair of the myopectineal orifice(MPO)are ne... BACKGROUND Inguinal hernias are common after surgery.Tension-free repair is widely accepted as the main method for managing inguinal hernias.Adequate exposure,coverage,and repair of the myopectineal orifice(MPO)are necessary.However,due to differences in race and sex,people’s body shapes vary.According to European guidelines,the patch should measure 10 cm×15 cm.If any part of the MPO is dissected,injury to the nerves,vascular network,or organs may occur during surgery,thereby leading to inguinal discomfort,pain,and seroma formation after surgery.Therefore,accurate localization and measurement of the boundary of the MPO are crucial for selecting the optimal patch for inguinal hernia repair.AIM To compare the size of the MPO measured on three-dimensional multislice spiral computed tomography(CT)with that measured via laparoscopy and explore the relevant factors influencing the size of the MPO.METHODS Clinical data from 74 patients who underwent laparoscopic tension-free inguinal hernia repair at the General Surgery Department of the First Affiliated Hospital of Anhui University of Science and Technology between September 2022 and July 2024 were collected and analyzed retrospectively.Transabdominal preperitoneal was performed.Sixty-four males and 10 females,with an average age of 58.30±12.32 years,were included.The clinical data of the patients were collected.The boundary of the MPO was measured on three-dimensional CT images before surgery and then again during transabdominal preperitoneal.All the preoperative and intraoperative data were analyzed via paired t-tests.A t-test was used for comparisons of age,body mass index,and sex between the groups.In the comparative analysis,a P value less than 0.05 indicated a significant difference.RESULTS The boundaries of the MPO on 3-dimensional CT images measured 7.05±0.47 cm and 6.27±0.61 cm,and the area of the MPO was 19.54±3.33 cm^(2).The boundaries of the MPO during surgery were 7.18±0.51 cm and 6.17±0.40 cm.The errors were not statistically significant.However,the intraoperative BD(the width of the MPO,P=0.024,P<0.05)and preoperative AC(the length of the MPO,P=0.045,P<0.05)significantly differed according to sex.The AC and BD measurements before and during surgery were not significantly different according to age,body mass index,hernia side or hernia type(P>0.05).CONCLUSION The application of this technology can aid in determining the most appropriate dissection range and patch size. 展开更多
关键词 HERNIA INGUINAL Myopectineal orifice three-dimensional reconstruction Computed tomography Inguinal hernia
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Application of Transvaginal Three-Dimensional Ultrasound in Assessing Endometrial Receptivity in Patients with Ovulation Disorder Infertility and the Impact on Subendometrial Vascular Index(VI)and Vascular Flow Index(VFI)Level
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作者 Yongping Sun 《Journal of Clinical and Nursing Research》 2025年第12期351-357,共7页
Objective:To analyze the diagnostic value of transvaginal three-dimensional ultrasound(3D-TVS)in evaluating endometrial receptivity(ER)for ovulation disorder infertility(ODI),and to investigate the impact of subendome... Objective:To analyze the diagnostic value of transvaginal three-dimensional ultrasound(3D-TVS)in evaluating endometrial receptivity(ER)for ovulation disorder infertility(ODI),and to investigate the impact of subendometrial endometrial vascular index(VI)and endometrial vascular flow index(VFI)levels on ODI.Methods:A total of 110 patients diagnosed with ODI admitted between January 2023 and June 2024 were selected.All patients underwent ovulation induction therapy,3D-TVS examination,and sex hormone testing.Based on pregnancy outcomes,patients were divided into a successful pregnancy group(73 cases)and an unsuccessful pregnancy group(37 cases).ER parameters,sex hormone levels,and endometrial blood flow patterns were compared between the two groups.Receiver operating characteristic(ROC)curves were plotted to evaluate the predictive value of ER for ODI.Results:The spiral artery peak systolic velocity(PSV),endometrial volume(EMV),endometrial flow index(FI),and VFI in the successful pregnancy group were significantly higher than those in the unsuccessful pregnancy group(p<0.05).No significant differences were observed in other ER parameters between the two groups(p>0.05).There was no significant difference in sex hormone levels between the two groups on the day of human chorionic gonadotropin(hCG)treatment(p>0.05).Among the endometrial blood flow classifications in the pregnant group,the proportion of Type II was lower than that in the nonpregnant group(p<0.05).The Receiver Operating Characteristic(ROC)curve demonstrated that the area under the curve(AUC)for Endometrial Volume(EMV)in predicting pregnancy after Ovarian Dysfunction Infertility(ODI)treatment was 0.854,with a sensitivity of 92.61%and a specificity of 71.75%.The AUC for Vascularization Index(VI)was 0.771,with a sensitivity of 52.18%and a specificity of 88.70%.The AUC for Vascularization Flow Index(VFI)of the endometrium was 0.887,with a sensitivity of 80.01%and a specificity of 69.20%.Conclusion:Three-dimensional transvaginal sonography(3D-TVS)assessment of endometrial receptivity(ER)can effectively detect ODI,and the levels of subendometrial VI and VFI demonstrate superior predictive performance for pregnancy outcomes in this condition,serving as commonly used predictive indicators for the disease. 展开更多
关键词 Transvaginal three-dimensional ultrasound Endometrial receptivity Ovarian dysfunction infertility VI VFI
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Daily Evolution of Three-Dimensional Structure of a Subsurface Anticyclonic Eddy and Eddy-Induced Swirl Transport in the Canada Basin
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作者 XU Fan LI Haiyan +3 位作者 WANG Ru WEN Zhiqiang YANG Kun ZHANG Menghao 《Journal of Ocean University of China》 2025年第3期545-556,共12页
In recent years,research investigations have focused on the substantial freshwater storage in the Beaufort Gyre(BG)region due to climate change.Despite active mesoscale eddies in the area,a notable gap in understandin... In recent years,research investigations have focused on the substantial freshwater storage in the Beaufort Gyre(BG)region due to climate change.Despite active mesoscale eddies in the area,a notable gap in understanding the three-dimensional structure and induced transport has been observed.This study concentrates on the Canada Basin in the western Arctic Ocean,specifically examining a subsurface anticyclonic eddy(SAE)sampled by a Mooring A in the BG region.Hybrid Coordinate Ocean Model(HYCOM)analysis data reveal its lifecycle from February 15 to March 15,2017,marked by initiation,development,maturity,decay,and termination stages.This work extends the finding of SAE passing through Mooring A by examining its overall effects,spatiotemporal variations,and swirl transport.SAE generation through baroclinic instability,which contributes to the westward tilt of the vertical axis,is also confirmed in this study.Swirl transport induced by SAE is predominantly eastward and downward due to its trajectory and background flow.SAE temporarily weakens stratification and extends the subsurface depth but demonstrates transient effects.Moreover,SAE transports upper-layer freshwater,Pacific Winter Water,and Atlantic Water downward,emphasizing its potential influence on freshwater redistribution in the Canadian Basin.This research provides valuable insights into mesoscale eddy dynamics,revealing their role in modulating the upper water mass in the BG region. 展开更多
关键词 Beaufort Gyre mesoscale eddy three-dimensional structure swirl transport baroclinic instability
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High-performance Polydimethylsiloxane Composites Based on Ordered Three-dimensional PVA-MMT Aerogel Network:Network Structure Regulation and Mechanical Enhancement Mechanism
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作者 Zhe-Yu Yang Long-Jin Huang +6 位作者 Zhao-Qun Shao Yang Yang Xia-Yan Cao Zi-Han Wang Sheng Cui Chun-Hua Zhu Yu Liu 《Chinese Journal of Polymer Science》 2025年第11期2171-2184,I0016,共15页
To address the poor mechanical properties of polydimethylsiloxane(PDMS)and enhance the understanding of the reinforcement mechanisms of aerogel network structures in rubber matrices,this study reinforced PDMS using an... To address the poor mechanical properties of polydimethylsiloxane(PDMS)and enhance the understanding of the reinforcement mechanisms of aerogel network structures in rubber matrices,this study reinforced PDMS using an ordered interconnected three-dimensional montmorillonite(MMT)aerogel network.The average pore diameter of the aerogels was successfully reduced from 11.53μm to 2.51μm by adjusting the ratio of poly(vinyl alcohol)(PVA)to MMT via directional freezing.Changes in the aerogel network were observed in field emission scanning electron microscope(FESEM)images.After vacuum impregnation,the aerogel network structure of the composites was observed using FESEM.Tensile tests indicated that as the pore diameter decreased,the elongation at break of the composites first increased to a peak of329.61%before decreasing,while the tensile strength and Young's modulus continuously increased to their maximum values of 6.29 MPa and24.67 MPa,respectively.Meanwhile,FESEM images of the tensile cracks and fracture surfaces showed that with a reduction in aerogel pore diameter,the degrees of crack deflection and interfacial debonding increased,presenting a rougher fracture surface.These phenomena enable the composites to dissipate substantial energy during tension,thus effectively improving the mechanical strength of the composites.The present work elucidates the bearing of ordered three-dimensional aerogel network structures on the performance of rubber matrices and provides crucial theoretical insights and technical guidance for the creation and optimization of high-performance PDMS-based composites. 展开更多
关键词 Montmorillonite aerogel Polymer composites Mechanical property three-dimensional aerogel network
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