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An Ultralytics YOLOv8-Based Approach for Road Detection in Snowy Environments in the Arctic Region of Norway 被引量:2
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作者 Aqsa Rahim Fuqing Yuan Javad Barabady 《Computers, Materials & Continua》 2025年第6期4411-4428,共18页
In recent years,advancements in autonomous vehicle technology have accelerated,promising safer and more efficient transportation systems.However,achieving fully autonomous driving in challenging weather conditions,par... In recent years,advancements in autonomous vehicle technology have accelerated,promising safer and more efficient transportation systems.However,achieving fully autonomous driving in challenging weather conditions,particularly in snowy environments,remains a challenge.Snow-covered roads introduce unpredictable surface conditions,occlusions,and reduced visibility,that require robust and adaptive path detection algorithms.This paper presents an enhanced road detection framework for snowy environments,leveraging Simple Framework forContrastive Learning of Visual Representations(SimCLR)for Self-Supervised pretraining,hyperparameter optimization,and uncertainty-aware object detection to improve the performance of YouOnly Look Once version 8(YOLOv8).Themodel is trained and evaluated on a custom-built dataset collected from snowy roads in Tromsø,Norway,which covers a range of snow textures,illumination conditions,and road geometries.The proposed framework achieves scores in terms of mAP@50 equal to 99%and mAP@50–95 equal to 97%,demonstrating the effectiveness of YOLOv8 for real-time road detection in extreme winter conditions.The findings contribute to the safe and reliable deployment of autonomous vehicles in Arctic environments,enabling robust decision-making in hazardous weather conditions.This research lays the groundwork for more resilient perceptionmodels in self-driving systems,paving the way for the future development of intelligent and adaptive transportation networks. 展开更多
关键词 Autonomous vehicles self-driving vehicles road detection snow-covered roads YOLOv8 road detection using segmentation
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Research of Home Information Technology Adoption Model
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作者 Ao Shan Ren Weiyin +1 位作者 Lin Peishan Tang Shoulian 《信息通信技术》 2008年第5期10-16,共7页
The Information Technology at Home has caught the attention of various industries such as IT,Home Appliances,Communication,and Real Estate.Based on the information technology acceptance theories and family consumption... The Information Technology at Home has caught the attention of various industries such as IT,Home Appliances,Communication,and Real Estate.Based on the information technology acceptance theories and family consumption behaviors theories,this study summarized and analyzed four key belief variables i.e.Perceived Value,Perceived Risk,Perceived Cost and Perceived Ease of Use,which influence the acceptance of home information technology.The study also summaries three groups of external variables.They are social,industrial,and family influence factors.The social influence factors include Subjective Norm;the industry factors include the Unification of Home Information Technological Standards,the Perfection of Home Information Industry Value Chain,and the Competitiveness of Home Information Industry;and the family factors include Family Income,Family Life Cycle and Family Educational Level.The study discusses the relationship among these external variables and cognitive variables.The study provides Home Information Technology Acceptance Model based on the Technology Acceptance Model and the characteristics of home information technology consumption. 展开更多
关键词 家用信息技术 通信系统 发展现状 社会影响
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Introspective Study of Trans-Tibias Amputees in View of the Design of a Durable Prosthetic Foot
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作者 Boukar Abdelhakim Mahamat Maintah Ardjoune Debsi Edjibey 《Open Journal of Applied Sciences》 2025年第1期259-273,共15页
The prosthesis is an artificial device that can replace an organ of a human body member to restore a compromised function. It is necessary following the removal of a human organ, which can occur as a result of an illn... The prosthesis is an artificial device that can replace an organ of a human body member to restore a compromised function. It is necessary following the removal of a human organ, which can occur as a result of an illness, trauma or congenital malformation. The trans-tibia prosthesis, in particular, allows the amputee patient to recover the impaired function and regain autonomy, while facilitating their daily social integration. The trans-tibia prosthesis consists of a socket, a sleeve, connecting elements and a prosthetic foot. Each of these components plays a very important role. Among these components, the prosthetic foot usually called “SACH foot” is very often replaced due to cracking and therefore has a fairly short lifespan. At the Center for Equipment and Rehabilitation of Kabalaye (CERK), the SACH foot made using polyurethane and wood is imported and is given to patients with reduced mobility. The aim of this article is twofold, on the one hand, to make a social and pathological study of trans-tibia amputees in relation to the use of the SACH foot prosthesis, on the other hand, to compare this foot with a new prosthetic foot proposed and which is manufactured using extruded polystyrene. The result of prosthetic tests carried out on twenty-four amputees showed that the foot manufactured using extruded polystyrene is better in terms of resistance, bulk and adaptability to active amputees. 展开更多
关键词 Prosthesis Prosthetic Foot Trans-Tibia Amputee SACH Foot
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Reply to the“Discussion on“Data-driven Methods to Predict the Burst Strength of Corroded Line Pipelines Subjected to Internal Pressure”by Jie Cai et al.https://doi.org/10.1007/s11804-022-00263-0”
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作者 Jie Cai 《哈尔滨工程大学学报(英文版)》 2025年第1期252-253,共2页
With the booming of Industrial Internet of Things(IIoT)and Artificial Intelligence(AI),the objective of the work in Cai et al.(2022)is to explore the utilizing of data-driven methodology for the prediction of the burs... With the booming of Industrial Internet of Things(IIoT)and Artificial Intelligence(AI),the objective of the work in Cai et al.(2022)is to explore the utilizing of data-driven methodology for the prediction of the burst strength of cor‐roded pipelines,which can hopefully overcome the com‐mon drawbacks of widely-used traditional Finite Element Method(FEM)and the needs of sufficient domain knowl‐edge.The authors in Cai et al.(2022)are not aiming to overthrow the functionality and beneficence introduced by physical-based methods and widely-used empirical/semi-emprical engineering expressions,such as the DNV standars(DNVGL,2017)in offshore engineering. 展开更多
关键词 al. OVERCOME utilizing
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Do we actually understand the impact of renewables on electricity prices?A causal inference approach
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作者 Davide Cacciarelli Pierre Pinson +2 位作者 Filip Panagiotopoulos David Dixon Lizzie Blaxland 《iEnergy》 2025年第4期247-258,共12页
Understanding how renewable energy generation affects electricity prices is essential for designing efficient and sustainable electricity markets.However,most existing studies rely on regression-based approaches that ... Understanding how renewable energy generation affects electricity prices is essential for designing efficient and sustainable electricity markets.However,most existing studies rely on regression-based approaches that capture correlations but fail to identify causal relationships,particularly in the presence of non-linearities and confounding factors.This limits their value for informing policy and market design in the context of the energy transition.To address this gap,we propose a novel causal inference framework based on local partially linear double machine learning(DML).Our method isolates the true impact of predicted wind and solar power generation on electricity prices by controlling for high-dimensional confounders and allowing for non-linear,context-dependent effects.This represents a substantial methodological advancement over standard econometric techniques.Applying this framework to the UK electricity market over the period 2018-2024,we produce the first robust causal estimates of how renewables affect dayahead wholesale electricity prices.We find that wind power exerts a U-shaped causal effect:at low penetration levels,a 1 GWh increase reduces prices by up to£7/MWh,the effect weakens at mid-levels,and intensifies again at higher penetration.Solar power consistently reduces prices at low penetration levels,up to£9/MWh per additional GWh,but its marginal effect diminishes quickly.Importantly,the magnitude of these effects has increased over time,reflecting the growing influence of renewables on price formation as their share in the energy mix rises.These findings offer a sound empirical basis for improving the design of support schemes,refining capacity planning,and enhancing electricity market efficiency.By providing a robust causal understanding of renewable impacts,our study contributes both methodological innovation and actionable insights to guide future energy policy. 展开更多
关键词 Causal inference electricity prices renewable energy wind power solar power double machine learning
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A Bibliometric Study of Wollastonite as a New Natural Material in Cement-based Construction Materials-A Review
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作者 Kuldasheva Aziza HUANG Bin +1 位作者 Kuldashev Kholjigit LI Beixing 《Journal of Wuhan University of Technology(Materials Science)》 2025年第6期1651-1659,共9页
We tried to collect all publications based on Scopus for 24 years in English for the keyword Wollastonite.We analyzed the most popular journals,top authors,top-cited papers,and the role of top countries in the world o... We tried to collect all publications based on Scopus for 24 years in English for the keyword Wollastonite.We analyzed the most popular journals,top authors,top-cited papers,and the role of top countries in the world on the usage of Wollastonite in construction.Moreover,a comprehensive examination of literature and patent data pertaining to the production and utilisation of wollastonite and materials derived from wollastonite was conducted.We then consolidated and presented our findings about Wollastonite's characteristics.We demonstrated the theoretical possibility of using recycled wollastonite in some areas of cement-based construction materials and product manufacture.Our research results shows that the number of available articles on Wollastonite-mineral as a fibre and aggregate is less than that on other areas.In addition,the research enables us to discover potential deficiencies in the utilization of Wollastonite in situations where there is currently no available published literature. 展开更多
关键词 CITATIONS WOLLASTONITE JOURNALS concrete REVIEW SCOPUS
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Dynamic Cost-Benefit Analysis of Digitalization in the Energy Industry
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作者 Jose Angel Leiva Vilaplana Guangya Yang +2 位作者 Emmanuel Ackom Roberto Monaco Yusheng Xue 《Engineering》 2025年第2期174-187,共14页
Assessing the benefits and costs of digitalization in the energy industry is a complex issue.Traditional cost-benefit analysis(CBA)might encounter problems in addressing uncertainties,dynamic stakeholder interactions,... Assessing the benefits and costs of digitalization in the energy industry is a complex issue.Traditional cost-benefit analysis(CBA)might encounter problems in addressing uncertainties,dynamic stakeholder interactions,and feedback loops arising out of the evolving nature of digitalization.This paper introduces a methodological framework to help address the intricate inter connections between digital applications and business models in the energy industry.The proposed framework leverages system dynamics to achieve two primary objectives.It investigates how digitalization generally influences the value proposi-tion,value capture,and value creation dimensions of business models.It also quantifies the financial and social impacts of digitalization from a dynamic perspective.The proposed dynamic CBA allows for a more precise quantification of the benefits and costs,associated with evidence-based decision-making.Findings from an illustrative case study challenge the static assumptions of conventional methods.These methods often presume continuous operation,neglecting reinvestment and operational feedback loops,and resulting in negative net present values.Conversely,the outcomes of the proposed method indicate positive net present values when accounting for factors such as reinvestment rates and the will-ingness to invest in digitalization projects.The principles outlined in this paper can enable a more accu-rate assessment of digitalization projects,thus catalyzing the development of new CBA applications and guidelines for digitalization. 展开更多
关键词 System dynamics DIGITALIZATION Cost-benefit analysis Energy industry Business modeling Socioeconomic assessment
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Hybrid Nanofluids Mixed Convection inside a Partially Heated Square Enclosure with Driven Sidewalls
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作者 Meriem Bounib Aicha Bouhezza +4 位作者 Abdelkrim Khelifa Mohamed Teggar Hasan Köen Aissa Atia Yassine Cherif 《Frontiers in Heat and Mass Transfer》 2025年第4期1323-1350,共28页
This study investigates laminar convection in three regimes(forced convection,mixed convection,and natural convection)of a bi-nanofluid(Cu-Al_(2)O_(3)-water)/mono-nanofluid(Al_(2)O_(3)-water)inside a square enclosure ... This study investigates laminar convection in three regimes(forced convection,mixed convection,and natural convection)of a bi-nanofluid(Cu-Al_(2)O_(3)-water)/mono-nanofluid(Al_(2)O_(3)-water)inside a square enclosure of sliding vertical walls which are kept at cold temperature and moving up,down,or in opposite directions.The enclosure bottom is heated partially by a central heat source of various sizes while the horizontal walls are considered adiabatic.The thermal conductivity and dynamic viscosity are dependent on temperature and nanoparticle size.The conservation equations are implemented in the solver ANSYS R2(2020).The numerical predictions are successfully validated by comparison with data from the literature.Numerical simulations are carried out for various volume fractions of solid mono/hybrid-nanoparticles(0≤ϕ≤5%),Richardson numbers(0.001≤Ri≤10),and hot source lengths((1/5)H≤ε≤(4/5)H).Isothermal lines,streamlines,and average Nusselt numbers are analyzed.The thermal performance of nanofluids is compared to that of the base heat transfer fluid(water).Outcomes illustrate the flow characteristics significantly affected by the convection regime,hot source size,sidewall motion,and concentration of solid nanoparticles.In the case of sidewalls moving downward,using hybrid nanofluid(Cu-Al_(2)O_(3)-water)shows the highest heat transfer rate in the enclosure at Ri=1,ε=(4/5)H and volume fraction ofφ=5%where a significant increment(25.14%)of Nusselt number is obtained. 展开更多
关键词 Mixed convection heat transfer enhancement hybrid nanofluid nanoparticles Richardson number
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Optimized Eleutherine bulbosa Urb. bulb extract on the inhibition of 3D retinoblastoma spheroids cultured in type I murine collagen
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作者 Ammar Akram Kamarudin Nor Hafiza Sayuti +3 位作者 Mohamad Zulhafiz Shafiq Zulhilmi Cheng Norazalina Saad Nur Hanisah Azmi Norhaizan Mohd.Esa 《International Journal of Ophthalmology(English edition)》 2025年第5期802-812,共11页
AIM:To investigate the efficacy of Eleutherine bulbosa(Mill.)Urb.bulb extract(EBE)on the 3D human retinoblastoma cancer cells(WERI-Rb-1)spheroids and explore its apoptotic mechanism.METHODS:The 3D WERI-Rb-1 and human ... AIM:To investigate the efficacy of Eleutherine bulbosa(Mill.)Urb.bulb extract(EBE)on the 3D human retinoblastoma cancer cells(WERI-Rb-1)spheroids and explore its apoptotic mechanism.METHODS:The 3D WERI-Rb-1 and human retinal pigmented epithelium cells(ARPE-19)spheroids were developed using type 1 murine collagen that was excised from the rat tail tendon and cultured via hanging drop and embedded techniques.The cytotoxic activity was examined by Alamar blue assay meanwhile,the morphological characteristics were assessed by 4’,6-diamidino-2-phenylindole(DAPI)and scanning electron microscopy(SEM).The mRNA and protein expressions of apoptotic and antioxidant signal transduction pathways were explored to ascertain its molecular mechanisms.The statistical analysis was carried out using GraphPad Prism.RESULTS:The Alamar blue assay portrayed higher half maximal inhibitory concentration(IC50)values of EBE and cisplatin on 3D WERI-Rb-1 model as compared to the previous study on 2D model.The results of DAPI and SEM illustrated apoptotic features upon treatment with EBE and cisplatin in a dose-dependent manner on 3D WERI-Rb-1 model.The mRNA and protein levels of apoptotic and antioxidant-related pathways were significantly affected by EBE and cisplatin,respectively(P<0.05).The regulation of gene and protein expressions of 3D WERI-Rb-1 spheroids differed from the 2D study,suggesting that the tumor microenvironment of extracellular matrix(ECM)collagen matrix hindered the EBE treatment efficacy,leading to apoptotic evasion.CONCLUSION:A significant inhibition effect of EBE is observed on the 3D WERI-Rb-1 spheroids.The presence of ECM causes an increase in cytotoxic resistance upon treatment with EBE and cisplatin. 展开更多
关键词 Eleutherine bulbosa Urb 3D WERI-Rb-1 spheroids APOPTOTIC ANTIOXIDANTS
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DNAJB6:A guardian against neurodegeneration
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作者 JónváHentze Anna Gelman +1 位作者 Tomasz Brudek Christian Hansen 《Neural Regeneration Research》 2026年第6期2169-2177,共9页
Amyloid protein aggregation plays a major role in multiple neurodegenerative diseases and is likely the primary driving force for the progression of most of these diseases.Multiple recent studies have highlighted that... Amyloid protein aggregation plays a major role in multiple neurodegenerative diseases and is likely the primary driving force for the progression of most of these diseases.Multiple recent studies have highlighted that the DNAJ homolog subfamily B member 6(DNAJB6)chaperone is particularly interesting,when it comes to preventing amyloidogenic proteins from aggregating.It has been shown that DNAJB6 can prevent the aggregation of polyglutamine-expanded proteins in models of Huntington’s disease.Likewise,it can suppress aggregation ofα-synuclein in models of Parkinson’s disease and other synucleinopathies.Finally,it has been shown that DNAJB6 can block aggregation of multiple additional amyloid proteins involved in Alzheimer’s disease and other tauopathies as well.We believe there is yet much to learn about the protective role of DNAJB6 in the brain,but this focused review summarizes,what we know so far of this chaperone.It describes the biological role of DNAJB6 in the brain and its interaction with Hsp70,with particular emphasis on the studies that show its ability to prevent amyloid protein aggregation in vitro and in vivo.Moreover,recent work on dysregulation of the expression of DNAJB6 in brain clinical tissue is discussed.Finally,we discuss potential therapeutic perspectives as we believe this protein is a promising druggable target. 展开更多
关键词 AGGREGATION CHAPERONES clinical tissues DNAJB6 human brain NEURODEGENERATION neurodegenerative diseases therapeutic target
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KONUS dynamics for a 750 MHz IH-based injector
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作者 J.Giner Navarro C.Oliver +7 位作者 D.Gavela V.Bencini A.Lombardi P.Calvo G.Moreno M.León A.Rodríguez J.M.Carmona 《Nuclear Science and Techniques》 2026年第3期65-78,共14页
In response to the increasing demand for hadron therapy facilities,significant efforts have been directed toward enhancing the performance of high-gradient and high-transmission injectors for light ion beams.For carbo... In response to the increasing demand for hadron therapy facilities,significant efforts have been directed toward enhancing the performance of high-gradient and high-transmission injectors for light ion beams.For carbon ion irradiations,which offer greater radiobiological efficiency in tumor treatment,recent research has focused on developing high-production sources of fully stripped C^(6+)ions and highly compact,high-frequency RFQ cavities.This study explores the design possibilities of a carbon ion acceleration section using 750 MHz Interdigital H-mode Drift Tube Linacs(IH-DTLs)as a high-efficiency solution for accelerating ions in the 5-10 MeV per nucleon energy range.A particle-tracking routine based on the TRAVEL code was developed to design the acceleration line through a tailored KONUS-type configuration.Three design solutions were proposed and compared,exploring different alternatives regarding the use of a MEBT to match the output beam phase space of the RFQ to the optics of the line,as well as varying considerations for magnetic systems to focus the beam.Additionally,the compatibility of the proposed solutions with the existing design of the carbon ion bent-linac for hadron therapy was assessed. 展开更多
关键词 ACCELERATOR INJECTOR LINAC IH KONUS dynamics Hadron therapy
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Dynamics Analysis of the Baiyun Sag in the Pearl River Mouth Basin,North of the South China Sea 被引量:15
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作者 SUN Zhen ZHONG Zhihong +5 位作者 ZHOU Di PANG Xiong HUANG Chunju CHEN Changmin HE Min XU Hehua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第1期73-83,共11页
The Baiyun sag is a deep one developing on the slope of the Pearl River Mouth Basin. It occurs as a composite graben horizontally, and is composed of two sub-sags versus one low uplift. Vertically, the sedimentary arc... The Baiyun sag is a deep one developing on the slope of the Pearl River Mouth Basin. It occurs as a composite graben horizontally, and is composed of two sub-sags versus one low uplift. Vertically, the sedimentary architecture could be divided into three layers, i.e. the faulted layer on the bottom, the faulted-ductile stretching layer in the middle and the draping layer on the top. The main rifting stage of the sag is supposed to be characterized by ductile extension and thinning of the crust. The special deformation pattern is probably attributed to the fact that the Baiyun sag is located in the transfer zone of the pre-existing weak zone, which made the sag a strongly deformed area, characterized by the greatly thinned lithosphere and active magmatism. The highly rising mantle under the Baiyun sag should be an important mechanism responsible for the ductile deformation, which caused partial melting of the upper mantle. Upweiling to the upper crust and the sedimentary layers, the partial melting materials accommodated extensional strain and caused non-faulted vertical subsidence. Magma was collected under the transfer zone after the first stage of rifting, and transferred laterally in a direction perpendicular to the extension to the ENE and WSW parts of the sag and upwelled along the NW-trending basal faults, where WNW-trending shear faults developed in swarms. The faulting activity and sedimentation history of the Baiyun sag may have been affected by the ocean ridge jump around 24 Ma and the cessation of sea floor spreading around 16 Ma. 展开更多
关键词 Baiyun sag dynamics analysis transfer zone ductile extension
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Fractionation of Zn,Cd and Pb in a Tropical Soil After Nine-Year Sewage Sludge Applications 被引量:9
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作者 T.A.R.NOGUEIRA W.J.MELO +3 位作者 I.M.FONSECA S.A.MARCUSSI G.M.P.MELO M.O.MARQUES 《Pedosphere》 SCIE CAS CSCD 2010年第5期545-556,共12页
A long-term field experiment was carried out in the experiment farm of the Sao Paulo State University,Brazil,to evaluate the phytoavailability of Zn,Cd and Pb in a Typic Eutrorthox soil treated with sewage sludge for ... A long-term field experiment was carried out in the experiment farm of the Sao Paulo State University,Brazil,to evaluate the phytoavailability of Zn,Cd and Pb in a Typic Eutrorthox soil treated with sewage sludge for nine consecutive years,using the sequential extraction and organic matter fractionation methods.During 2005-2006,maize(Zea mays L.) was used as test plants and the experimental design was in randomized complete blocks with four treatments and five replicates.The treatments consisted of four sewage sludge rates(in a dry basis):0.0(control,with mineral fertilization),45.0,90.0 and 127.5 t ha-1,annually for nine years.Before maize sowing,the sewage sludge was manually applied to the soil and incorporated at 10 cm depth.Soil samples(0-20 cm layer) for Zn,Cd and Pb analysis were collected 60 days after sowing.The successive applications of sewage sludge to the soil did not affect heavy metal(Cd and Pb) fractions in the soil,with exception of Zn fractions.The Zn,Cd and Pb distributions in the soil were strongly associated with humin and residual fractions,which are characterized by stable chemical bonds.Zinc,Cd and Pb in the soil showed low phytoavailability after nine-year successive applications of sewage sludge to the soil. 展开更多
关键词 heavy metals humic substance sequential extraction Zea mays L.
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Combination Effect of Si and P on Tertiary Scale Characteristic of Hot Rolled Strip 被引量:7
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作者 Yang YU Chang WANG +3 位作者 Lin WANG Jin CHEN Ya-jun HUI Chang-ku SUN 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2015年第3期232-237,共6页
For high strength interstitial free (IF) steel containing P element, the salt and pepper (SP) defects exist on the strip surface and could not be eliminated effectively by optimizing the hot rolling process, such ... For high strength interstitial free (IF) steel containing P element, the salt and pepper (SP) defects exist on the strip surface and could not be eliminated effectively by optimizing the hot rolling process, such as temperature and cooling water. The combination effect of Si and P on the characteristic of tertiary scale has been studied comprehensively by scanning electron microscopy (SEM) and electron probe microanalysis (EPMA), and the concept is proposed firstly that Si and P are of combination effect which can be utilized to eliminate the SP defect. The results show that the SP defects were induced by the rolled-in scale during finish rolling. P can be enriched at the interface between substrate and tertiary scale, which is easy to decrease the adhesion of tertiary scale. However, Si enrichment at the interface between substrate and tertiary scale can increase the adhesion. The SP defects can be eliminated completely, which is attributed to the accompanying enrichment of Si and P. 展开更多
关键词 high strength IF steel containing P salt and pepper defect tertiary scale Si-P combination hot rolling
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Protective effect of the extract of Yi-Qi-Fu-Mai preparation on hypoxia-induced heart injury in mice 被引量:11
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作者 FENG Ya-Qian JU Ai-Chun +3 位作者 LIU Chun-Hua WANG Ting YU Bo-Yang QI Jin 《Chinese Journal of Natural Medicines》 SCIE CAS CSCD 2016年第6期401-406,共6页
Yi-Qi-Fu-Mai(YQFM) is extensively used clinically to treat cardiovascular diseases in China. To explore the anti-hypoxia effect of the extract of YQFM preparation(EYQFM), the EYQFM(1.4, 2.8, and 5.5 g·kg-1·d... Yi-Qi-Fu-Mai(YQFM) is extensively used clinically to treat cardiovascular diseases in China. To explore the anti-hypoxia effect of the extract of YQFM preparation(EYQFM), the EYQFM(1.4, 2.8, and 5.5 g·kg-1·d-1) was assessed for its heart-protective effect in a chronic intermittent hypoxia(CIH) animal model(oxygen pressure 7%-8%, 20 min per day) for 28 days of treatment. Betaloc(0.151 6 g·kg^(-1)·d^(-1)) was used as a positive control. The histopathological analyses of heart in CIH mice were conducted. Several cardiac state parameters, such as left ventricular ejection fractions(EF), stroke volume(SV), expression of creatine kinase(CK), lactate dehydrogenase(LDH), superoxide dismutase(SOD), and malondialdehyde(MDA) were measured. The results showed that treatment with EYQFM markedly reversed swelling of the endothelial cells and vacuolization in the heart when compared with the model group. Further study demonstrated that EYQFM significantly improved ventricular myocardial contractility by increasing EF and SV. In addition, EYQFM inhibited the activity of CK, LDH, decreased the level of MDA and improved SOD activity. The results demonstrated that EYQFM significantly improved the tolerability of myocardium to hypoxia and ameliorated the cardiac damage in the CIH model. 展开更多
关键词 Extract of YQFM preparation Chronic intermittent hypoxia Cardiac damage
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Enhanced Photocatalytic Activity of ZnO/CuO Nanocomposites Synthesized by Hydrothermal Method 被引量:5
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作者 Tongqin Chang Zijiong Li +2 位作者 Gaoqian Yun Yong Jia Hongjun Yang 《Nano-Micro Letters》 SCIE EI CAS 2013年第3期163-168,共6页
In this paper, we have demonstrated a facile and low-cost synthesis of the ZnO/CuO nanocomposites by two-step hydrothermal methods. The photocatalytic properties of the as-synthesized ZnO/CuO nanocomposites have been ... In this paper, we have demonstrated a facile and low-cost synthesis of the ZnO/CuO nanocomposites by two-step hydrothermal methods. The photocatalytic properties of the as-synthesized ZnO/CuO nanocomposites have been evaluated by the photodegradation of methylene blue(MB) and methyleneorange(MO) under UV irradiation. Experimental results show that MB and MO can be degraded completely within 15 and 25 min by the ZnO/CuO nanocomposites and its photodegradation rate is 6 times faster than that of pure ZnO. This enhanced photocatalytic activity can be ascribed to the low recombination probability of photo-induced carriers due to the efficient charge transfer in the nanocomposites. The as-synthesized ZnO/CuO nanocomposite may be a promising candidate for dye photodegradation of wastewaters. 展开更多
关键词 Photocatalytic degradation NANOCOMPOSITES ZnO/CuO HYDROTHERMAL
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Influence of laser linewidth on performance of Brillouin optical time domain reflectometry 被引量:6
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作者 郝蕴琦 叶青 +2 位作者 潘政清 蔡海文 瞿荣辉 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期257-261,共5页
The effects of optical sources with different laser linewidths on Brillouin optical time domain reflectometry (BOTDR) are investigated numerically and experimentally. Simulation results show that the spectral linewi... The effects of optical sources with different laser linewidths on Brillouin optical time domain reflectometry (BOTDR) are investigated numerically and experimentally. Simulation results show that the spectral linewidth of spontaneous Brillouin scattering remains almost constant when the laser linewidth is less than 1 MHz at the same pulse width; otherwise, it increases sharply. A comparison between a fiber laser (FL) with 4-kHz linewidth at 3 dB and a distributed feedback (DFB) laser with 3-MHz linewidth is made experimentally. When a constant laser power is launched into the sensing fiber, the fitting linewidths of the beat signals (backscattered Brillouin light and local oscillator (LO)) is about 5 MHz wider for the DFB laser than for the FL and the intensity of the beat signal is about a half. Furthermore, the frequency fluctuation in the long sensing fiber is lower for the FL source, yielding about 2 MHz less than that of the DFB laser, indicating higher temperature/strain resolution. The experimental results are in good agreement with the numerical simulations. 展开更多
关键词 Brillouin optical time domain reflectometry (BOTDR) laser linewidth distributed feedback laser fiber laser
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Use of High-Yielding Bioenergy Plant Castor Bean(Ricinus communis L.) as a Potential Phytoremediator for Copper-Contaminated Soils 被引量:8
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作者 R. ANDREAZZA L. BORTOLON +1 位作者 S. PIENIZ F. A. O. CAMARGO 《Pedosphere》 SCIE CAS CSCD 2013年第5期651-661,共11页
Copper (Cu) contamination in the environment has been increased during the years with agricultural and industrial activities. Biotechnological approaches are needed for bioremediation in these areas. The aims of thi... Copper (Cu) contamination in the environment has been increased during the years with agricultural and industrial activities. Biotechnological approaches are needed for bioremediation in these areas. The aims of this study were i) to evaluate the phytoreme- diation capacity of the high-yielding bioenergy plant castor bean (Ricinus communis L.) in vineyard soils (Inceptisol and Mollisol) contaminated with Cu and a Cu mining waste; ii) to characterize the castor bean as a Cu phytoremediation plant; and iii) to evaluate the nutrient uptake by castor bean. Castor bean plants cultivated in soil with toxic levels of Cu for 57 d exhibited high phytomass production, a high tolerance index of roots' fresh mass and shoots' dry mass, a high level of Cu phytoaccumulation in the roots and also, a robust capacity for Cu phytostabilization. Furthermore, castor bean plants did not significantly deplete soil nutrients (such as N, P, and Mg) during cultivation. Plants cultivated in Inceptisol, Mollisol and Cu mining waste exhibited a strong potential for Cu phytoaccumulation, with values of 5900, 3 052 and 2805 g ha-1, respectively. In addition, the castor bean's elevated phytomass production and strong growth in Cu-contaminated soils indicated a high level of Cu phytoaccumulation and a potential application in biofuels. These findings indicate that the castor bean is a efficient hyperaccumulator of Cu and a potential candidate plant for the phytoremediation of Cu-contaminated soil. 展开更多
关键词 biofuels PHYTOACCUMULATION PHYTOREMEDIATION PHYTOSTABILIZATION
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Dynamic Analysis on Rifting Stage of Pearl River Mouth Basin through Analogue Modeling 被引量:7
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作者 孙珍 周蒂 +4 位作者 孙龙涛 陈长民 庞雄 姜建群 樊浩 《Journal of Earth Science》 SCIE CAS CSCD 2010年第4期439-454,共16页
The Pearl River Mouth basin (PRMB) is a marginal sedimentary basin of the South China Sea. It trends NE and is divided into three segments from west to east by two NW-trending faults. Changing dramatically in struct... The Pearl River Mouth basin (PRMB) is a marginal sedimentary basin of the South China Sea. It trends NE and is divided into three segments from west to east by two NW-trending faults. Changing dramatically in structures along and across strike, the PRMB is a good example to analyze main factors that might control the process of a continental rift basin's extension. Through five series of analogue experiments, we investigate the role of different factors, such as pre-existing discontinuities of crust, rheological profiles of lithosphere, kinematics of extension and presence of magmatic bodies and strong crustal portions (rigid massifs) on the development of basin's structures. After being compared with the architecture of the natural prototype, the results of the analogue models were compared with the architecture of the natural prototype and used to infer the role of the different factors controlling the formation and evolution of the PRMB. The main conclusions are as follows. (1) Affected by pre-Cenozoic structures, the PRMB was controlled by crosscut NE- and NW-trending initial faults, and the NW-trending Yitong'ansha (--~l~) fault may be a through-going fault along dip and offset the NE-trending rift and faults, while the Enpingdong (和统暗沙) fault might exist only in the middle and south. (2) The NW-trending faults may orient WNW to be sinistrally transtensional under SE to nearly NS extension. (3) The thickness ratio of brittle over ductile crust in Baiyun (白云) sag is lessthan normal, suggesting an initially hot and weak lithosphere. (4) The magma must have taken part in the rifting process from early stage, it may occur initially upon or slightly south of the divergent boundary in the middle segment. The flow of magma toward rift boundary faults caused extra vertical subsidence above the initial magma reservoir without creating a large extensional fault. (5) The rigid massif contributed to the strain partition along and across basin strike. 展开更多
关键词 Pearl River Mouth basin analogue modeling controlling factor of continental rift basin.
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Modeling of numerical simulation and experimental verification for carburizing-nitriding quenching process 被引量:9
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作者 R. MUKAI T. MATSUMOTO +3 位作者 JU Dong-ying T. SUZUKI H. SAITO Y. ITO 《中国有色金属学会会刊:英文版》 CSCD 2006年第B02期566-571,共6页
A model considering quantitative effects of diffused carbon and nitrogen gradients and kinetics of phase transformation is presented to examine metallo-thermo-mechanical behavior during carburized and nitrided quenchi... A model considering quantitative effects of diffused carbon and nitrogen gradients and kinetics of phase transformation is presented to examine metallo-thermo-mechanical behavior during carburized and nitrided quenching. Coupled simulation of diffusion, phase transformation and stress/strain provides the final distribution of carbon and nitrogen contents as well as residual stress and distortion. Effects of both transformation and lattice expansion induced by carbon and nitrogen absorption were introduced into calculating the evolution of the internal stress and strain. In order to verify the method and the results, the simulated distributions of carbon and nitrogen content and residual stress/strain of a ring model during carburized and nitrided quenching were compared with the measured data. 展开更多
关键词 金属热处理 渗碳 渗氮 淬火过程 数值模拟 模型 实验验证
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