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Universal design of three-dimensional porous graphene-iron based promotors for kinetically rationalized lithium-sulfur chemistry

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Journal of Energy Chemistry 2025年第1期100卷 192-200页

作者： Hua Gao Yunfeng Zhang Menglei Wang Ruoxuan Yang Shuai Feng Xuan Cao Yaping Zhang Zhongyuan Lu Yingze Song State Key Laboratory of environment-Friendly Energy Materials School of Materials and Chemistry Southwest University of Science and Technology School of Material Science and engineering Henan University of Technology College of Chemistry and Chemical engineering Taishan University

Lithium-sulfur （Li-S） batteries are widely deemed to be one of the most potential candidates for future secondary batteries because of their remarkable energy ***,notorious polysulfide shuttling and retarded sulfur reaction kinetics pose significant obstacles to the further application of Li-S *** rationally designed highly active electrocatalysts can facilitate polysulfide conversion,the universal and scalable synthesis strategies need to be ***,a universal synthetic strategy to construct a series of three-dimensional （3D） porous graphene-iron （3DGr-Fe） based electrocatalysts involving 3DGr-FeP,3DGr-Fe3C,and 3DGr-Fe3Se4is exploited for manipulating the Li-S redox *** has been observed that the implementation of a 3D porous Gr architecture leads to the well-designed conductive networks,while the uniformly dispersed iron nanoparticles introduce an abundance of active sites,fostering the lithium polysulfide conversion,thereby bolstering the overall electrochemical *** Li-S battery with the 3DGr-Fe based electrocatalyst exhibits remarkable capacity retention of 94.8%upon 100 times at 0.2 ***,the soft-packaged Li-S pouch cell based on such a 3DGr-Fe electrocatalyst delivers superior capacity of 1060.71 mA h g-1and guarantees for the continuous 30 min work of fan *** investigation gives comprehensive insights into the design,synthesis,and mechanism of 3DGr-Fe based electrocatalysts with high activity toward efficient and durable Li-S batteries.

关键词： Lithium-sulfur battery Universal synthesis 3D graphene-iron based promotor Electrocatalysis

Semantic Segmentation of Lumbar Vertebrae Using Meijering U-Net(MU-Net)on Spine Magnetic Resonance Images

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Computer Modeling in engineering & Sciences 2025年第1期142卷 733-757页

作者： Lakshmi S V V Shiloah Elizabeth Darmanayagam Sunil Retmin Raj Cyril department of Computer Science and engineering College of Engineering GuindyAnna UniversityChennai600025India department of Information Technology Madras Institute of TechnologyAnna UniversityChrompetChennai600044India

Lower back pain is one of the most common medical problems in the world and it is experienced by a huge percentage of people *** to its ability to produce a detailed view of the soft tissues,including the spinal cord,nerves,intervertebral discs,and vertebrae,Magnetic Resonance Imaging is thought to be the most effective method for imaging the *** semantic segmentation of vertebrae plays a major role in the diagnostic process of lumbar *** is difficult to semantically partition the vertebrae in Magnetic Resonance Images from the surrounding variety of tissues,including muscles,ligaments,and intervertebral discs.U-Net is a powerful deep-learning architecture to handle the challenges of medical image analysis tasks and achieves high segmentation *** work proposes a modified U-Net architecture namely MU-Net,consisting of the Meijering convolutional layer that incorporates the Meijering filter to perform the semantic segmentation of lumbar vertebrae L1 to L5 and sacral vertebra ***-colour mask images were generated and used as ground truth for training the *** work has been carried out on 1312 images expanded from T1-weighted mid-sagittal MRI images of 515 patients in the Lumbar Spine MRI Dataset publicly available from Mendeley *** proposed MU-Net model for the semantic segmentation of the lumbar vertebrae gives better performance with 98.79%of pixel accuracy(PA),98.66%of dice similarity coefficient(DSC),97.36%of Jaccard coefficient,and 92.55%mean Intersection over Union(mean IoU)metrics using the mentioned dataset.

关键词： Computer aided diagnosis(CAD) magnetic resonance imaging(MRI) semantic segmentation lumbar vertebrae deep learning U-Net model

Comparison between the seismic response of 2D and 3D models of rigid blocks

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Earthquake engineering and engineering Vibration 2014年第1期13卷 151-162页

作者： Angelo Di Egidio Daniele Zulli Alessandro Contento department of Civil engineering Architecture and Environment(DICEAA)University of L'Aquila

A three-dimensional rigid body on the shape of a parallelepiped is modelled in order to rock on a side or a vertex of the base,in order to evaluate the seismic response of rigid blocks lying on a horizontal *** center of mass of the body is considered as eccentric with respect to its geometric *** seismic input,three Italian recorded accelerograms,with different spectral content,are *** study is mainly conducted to highlight the differences between the seismic response of 2D and 3D models of rigid blocks,with the aim to understand if,in some cases,the use of the 3D model of rigid block is required to obtain safer *** fact,the outcomes show that in some ranges of the geometrical and mechanical parameters that characterize the excitation and the body,a two-dimensional model,which is not able to consider the 3D rocking on a vertex,can provide unsafe *** particular,it is found that the overturning process of the three-dimensional block can occur under excitations which are lower than those which overturn a corresponding two-dimensional block.

关键词： seismic excitation 3D rigid block rectangular base rocking overturning

Effect of a Carbon Fibre-steel Fibre-graphite Conductive Filler on the Electrothermal Properties of Cementitious Materials

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期 141-151页

作者：樊亚男 WEI Hong ZHENG Hongyong DU Hongxiu department of architecture and environmental engineering Taiyuan University College of Civil engineering Taiyuan University of Technology

Carbon fibre,steel fibre and graphite were used as conductive fillers to prepare cementitious materials with excellent electrothermal *** electrically conductive cementitious materials with different volume dosages were analysed through compressive and flexural strength,electrochemical impedance spectroscopy and temperature rise *** equivalent circuit model was established to study the electrically conductive heat generation mechanism in the electrically conductive cementitious *** results indicate that the mechanical properties of cementitious composite materials with a ternary conductive phase are better than those of pristine cementitious materials because the fibrous filler improves their mechanical ***,the incorporation of graphite in the material reduces its *** fibrous and point-like conductive phase materials into the cementitious material enhances the overall conductive pathway and considerably reduces the electrical resistance of the cementitious material,enhancing its conductive *** volume ratios of carbon fibre,steel fibre and graphite that achieve an optimal complex doping in the cementitious material were 0.35%,0.6% and 6%,*** was determined using the mutation point of each circuit element parameter as the percolation *** addition,at a certain safety voltage,there is a uniform change between the internal and surface temperatures of the conductive cementitious material,and the heating effect in this materialis is considerably better than that in the pristine cementitious material.

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Membrane fouling in ultrafiltration of natural water after pretreatment to different extents

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Journal of environmental Sciences 2016年第5期28卷 234-243页

作者： Lu Ao Wenjun Liu Lin Zhao Xiaomao Wang School of environment Tsinghua University department of National Defence architecture Planning & environmental engineering Logistic Engineering University

The combined fouling during ultrafiltration（UF） of surface water pretreated to different extents was investigated to disclose the roles of polysaccharides, proteins, and inorganic particles in UF membrane fouling. Both reversible and irreversible fouling decreased with enhanced pretreatment（biologically active carbon（BAC） treatment and sand filtration）. The sand filter effluent fouled the membrane very slowly. The UF membrane removed turbidity to less than 0.1 nephelometric turbidity unit（NTU）, reduced polysaccharides by 25.4%–29.9%, but rejected few proteins. Both polysaccharides and inorganic particles were detected on the fouled membranes, but inorganic particles could be effectively removed by backwashing. The increase of turbidity in the sand filter effluent to 3.05 NTU did not significantly increase the fouling rate, but an increase in the turbidity in the BAC effluent to6.11 NTU increased the fouling rate by more than 100%. The results demonstrated that the polysaccharide, not the protein, constituents of biopolymers were responsible for membrane fouling. Membrane fouling was closely associated with a small fraction of polysaccharides in the feed water. Inorganic particles exacerbated membrane fouling only when the concentration of fouling–inducing polysaccharides in the feed water was relatively high. The combined fouling was largely reversible, and polysaccharides were the predominant substances responsible for irreversible fouling.

关键词： Ultrafiltration Membrane fouling Biopolymer Polysaccharide Pretreatment

Changes in Agricultural System as Farmers Adapt to Economic-Social and Climatic Changes in the Min Upriver Rural Areas in Western Sichuan,Southwestern China

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Journal of Mountain Science 2015年第3期12卷 747-758页

作者： ZHANG Long-jiang TANG Ya LIU Ben-hong department of environment College of Architecture and EnvironmentSichuan University

Rapid economic growth in China has brought about great economic-social changes in rural areas, having considerable impact on the society in economy and environment. With a per capita possession of about 0.08 ha of cropland, Chinese farmers in rural areas adopt various ways in response to these changes in a bit to maintain their livelihood, wherein the agricultural system is facing one more options possible. To understand how rural communities have used different mechanisms to adapt to the economic and natural changes, we joined a survey in dry valleys of the Min upriver area under Maoxian county of western Sichuan province, southwestern China and visited the local people. Changes in the main crop cultivation have shown up an important means to keep up their household income. Farm households start seeking economic growth through diversified cultivating of cereal and economic crops in five lines, namely cereal, apple monoculture, apple and vegetables, plum and vegetables, mixed fruits and vegetables. These new lines mirror farmers' flexibility to cope with today's economic-social and climatic changes. The farming operation has changed all the more from a subsistence on grain to special agricultural products. Economic reforms in the early 1980 s motivated theprogress first in conversion of production from grain to fruits, and the desire to increase family income turned out to be an impetus for the subsequent events. At present, more farmers moving out of the rural areas, uneasy availability of labor force, increased opportunity cost of labors and their wages, increased farm size, and the urgent demand for the agricultural labor force, all these combine into the trend of the agricultural system of China on facing further economic-social reforms and reconstruction of the countryside across China.

关键词： Agricultural system Climate change Farmers Economic impacts Social change MinRiver

Quantification of emission variability for off-road equipment in China based on real-world measurements

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Frontiers of environmental Science & engineering 2022年第2期16卷 125-136页

作者： Kaili Pang Kaishan Zhang Shuai Ma Xiangrui Meng department of environmental Science and engineering College of Architecture and EnvironmentSichuan UniversityChengdu 610065China

The objective of this paper is to quantify the variability in emissions of off-road equipment using a portable emission measurement system.A total of 53 commonly used equipment for agriculture,base construction,paving construction,and material handling were ***-based and fuel-based emissions were quantified by different duty and engine *** duty modes(idling,moving,and working)were *** engine modes were defined based on normalized engine revolutions-per-minute and manifold absolute pressure,*** emission factors taking into account both duty modes and its corresponding time percentage during a typical duty cycle were *** showed that there existed a large off-road equipment variability in *** on duty and engine modes,time-based NO emissions ranged from 3.1 to 237.9,29.1‒1475.6,83.2‒681.6,and 3.2‒385.2 g/h for agriculture,base construction,paving construction and material handling equipment,respectively while for fuel-based NO emissions these ranges were 5.3‒52.0,11.7‒69.0,4.8‒30.8,and 11.0‒54.6 g/kg,***,emission factors derived from this study exhibited a much larger variability compared to those used in NONROAD by US EPA and National Guideline for Off-road Equipment of *** implied that localized measurements of emissions are needed for improvement of accuracy of emission ***,both equipment types and operations should be considered for development of emission inventory and control strategy.

关键词： Off-road equipment Portable emission measurement system(PEMS) Real-world emissions Diesel engine

Experimental investigations on the heat transfer characteristics of micro heat pipe array applied to flat plate solar collector

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Science China(Technological Sciences) 2013年第5期56卷 1177-1185页

作者： DENG YueChao QUAN ZhenHua ZHAO YaoHua WANG LinCheng department of Building environment and Facility engineering College of Architecture and Civil EngineeringBeijing University of Technology

This paper introduces a novel fiat plate solar collector （FPC） using micro heat pipe array （MHPA） as a key element. To analyze the thermal transfer behavior of flat plate solar collector with micro heat pipe array （MHPA-FPC）, an indoor experiment for thermal transfer characteristic of MHPA applied to FPC was conducted by using an electrical heating film to simulate the solar radiation. Different cooling water flow rates, cooling water temperatures, slopes, and contact thermal resistances be- tween the condenser of MHPA and the heat exchanger were tested at different heating powers. The experimental results in- dicate that MHPA-FPC exhibits the enhanced heat transfer capability with increased cooling water flow rate and temperature. Total thermal resistance has a maximum decline of approximately 10% when the flow rate increases from 180 to 360 L h-1 and 38% when the cooling water temperature increases from 20~C to 40~C. When the inclination angle of MHPA-FPC ex- ceeds 30~, the slope change has a negligible effect on the heat transfer performance of MHPA-FPC. In addition, contact thermal resistance significantly affects the heat transfer capability of MHPA-FPC. The total thermal resistances lowers to nearly half of the original level when contact material between the condenser of MHPA and the heat exchanger changes from conductive silicone to conductive grease. These results could provide useful information for the optimal design and operation of MHPA-FPC.

关键词： micro heat pipe array novel fiat plate solar collector heat transfer characteristic cooling water flow rate cooling watertemperature slope contact thermal resistance

Impacts of reforestation on woody species composition,species diversity and community structure in dry-hot valley of the Jinsha River,southwestern China

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Journal of Mountain Science 2016年第12期13卷 2182-2191页

作者： GONG Zhi-lian TANG Ya department of environment College of Architecture and Environment Siehuan University Chengdu 510065 China department of environment engineering College of Energy and Environment Xihua University Chengdu 610039 China

To understand the impacts of reforestation on woody species composition,species diversity and community structure,seven plantation forests in dryhot valley of the Jinsha River in Southwest China were investigated,with adjacent wastelands,natural shrub grassland and a natural forest as *** importance value,species richness,species heterogeneity and Sorenson similarity index between plantations and the natural forest were *** indicated that compared to wastelands and natural shrub grassland,reforestation improved species diversity and community structure,and more forest woody species found suitable habitats in *** diversity in understory of plantations and Sorenson similarity index were significantly negatively correlated with stem density in mature plantations(26-31 years old).Higher species diversity and Sorenson similarity index existed in mature sparse plantations due to lower stem density and more tree species planted *** contrast,reference natural forest,with species heterogeneity of 2.28 for shrub layer,showed the highest species *** would take a long time for species composition and diversity to recover through reforestation in a dry-hot ***,it was essential to protect remnant natural forests strictly and reforest with suitable management such as lower stem density and increasing genetic diversity of trees planted.

关键词： Biodiversity Plantations Dry hot valley Genetic resources Natural forest Reforestation