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Enhancing Women's Well-being and Self-Confidence through Fragrance Cosmetics:Perceptions within Close and Broader Social Circles
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作者 Yang Fan Guo Miao +1 位作者 Zhou Ziyan Abriat Anne 《China Detergent & Cosmetics》 CAS 2024年第2期69-78,共10页
Mental and physical stress can affect people's self-confidence and happiness.The primary objective of this study is to develop an active fragrance that has been proved to have a positive effect on happiness and se... Mental and physical stress can affect people's self-confidence and happiness.The primary objective of this study is to develop an active fragrance that has been proved to have a positive effect on happiness and self-confidence based on the latest research results of aroma components and fragrance innovation.The active fragrance is applied to the cream formula to study the emotions it brings to the user and extend the research scope of the active emotion to the close and extensive social circle of users to see whether it can perceive it.This study provides a reference cosmetic solution for emotional regulating active fragrance. 展开更多
关键词 FRAGRANCE emotion CREAM social circle
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Spatial Distribution Characteristics and Coverage Rate of Commercial Facilities in 15-minute Radius Livelihood Service Circles of Chunshu Street
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作者 HAN Qiqi YANG Kaitai 《Journal of Landscape Research》 2024年第1期17-21,共5页
Building a 15-minute radius livelihood service circle from the needs of residents is a topdown process of optimizing urban layout and promoting high-quality development implemented by the government.In September 2022,... Building a 15-minute radius livelihood service circle from the needs of residents is a topdown process of optimizing urban layout and promoting high-quality development implemented by the government.In September 2022,Xicheng District of Beijing served as a national pilot of the 15-minute radius livelihood service circle.Based on the data of POI,urban walking network and building outline,this paper studies the coverage of commercial service facilities in the 15-minute radius livelihood service circle of Chunshu Street by using kernel density analysis and urban network analysis tools.The research shows that the commercial facilities are concentrated in Zhuangsheng Square and Dazhalan commercial district.There are large gaps in housekeeping and couriers logistics facilities,which need to be further improved. 展开更多
关键词 Chunshu Street 15-minute radius livelihood service circle POI Historic urban areas Community business
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Circle社交网络系统衍生的社区互助模式探究
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作者 黄浩 张华 《工业工程设计》 2024年第4期100-106,共7页
探究Circle社区网络系统衍生的社区互助模式并总结传统设计与协同创新设计对于协同设计者的职能要求。从多元主体、理念衍生与模式思辨三个层次梳理Circle服务系统流程及利益相关者,剖析Circle社区网络系统的设计模式。基于此,文章从行... 探究Circle社区网络系统衍生的社区互助模式并总结传统设计与协同创新设计对于协同设计者的职能要求。从多元主体、理念衍生与模式思辨三个层次梳理Circle服务系统流程及利益相关者,剖析Circle社区网络系统的设计模式。基于此,文章从行为认同、情感互动及体验价值三个层面建构了社区协同互助模式的设计策略,并进一步扩展出协同设计者的四条职能:思辨设计思维、跨学科知识体系、能级导向设计及协调创新。Circle社交网络系统衍生的社区协同互助模式在一定程度上能够引导和优化本土化社区的弹性和韧性,朝着更加有利于社会创新模式的方向不断发展。 展开更多
关键词 协同设计 社区互助模式 circle 协同设计者职能
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基于Circle映射和自适应t分布变异改进的鹈鹕优化算法
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作者 高猛 曾宪文 《计算机与现代化》 2024年第9期69-73,共5页
针对传统鹈鹕优化算法(POA)存在收敛速度慢、易陷入局部最优解等缺陷,提出一种基于Circle映射初始化和自适应t分布变异的改进的鹈鹕优化算法(IPOA)。首先,在种群初始化阶段,采用Circle映射生成具有高度多样性的初始解,并结合反向学习策... 针对传统鹈鹕优化算法(POA)存在收敛速度慢、易陷入局部最优解等缺陷,提出一种基于Circle映射初始化和自适应t分布变异的改进的鹈鹕优化算法(IPOA)。首先,在种群初始化阶段,采用Circle映射生成具有高度多样性的初始解,并结合反向学习策略,提高种群多样性,增强种群的探索能力。其次,在迭代过程中,采用自适应t分布变异操作对个体进行扰动,有助于鹈鹕优化算法跳出局部最优解并提高收敛速度。另外,在鹈鹕优化算法的探索阶段引入自适应因子和改进惯性权重,更好地平衡算法全局探索能力和局部开发能力。最后,在多个测试函数上将IPOA与其他4种经典算法进行比较。实验结果表明,IPOA在收敛速度、全局搜索能力和收敛鲁棒性方面均有显著提升。 展开更多
关键词 鹈鹕优化算法 circle映射 自适应因子 自适应t分布变异
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Frost deformation and microstructure evolution of porous rock under uniform and unidirectional freeze-thaw conditions
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作者 LV Zhitao LIU Jintao +1 位作者 WAN Ling LIU Weiping 《Journal of Mountain Science》 SCIE CSCD 2024年第8期2855-2869,共15页
The frost deterioration and deformation of porous rock are commonly investigated under uniform freeze-thaw(FT)conditions.However,the unidirectional FT condition,which is also prevalent in engineering practice,has rece... The frost deterioration and deformation of porous rock are commonly investigated under uniform freeze-thaw(FT)conditions.However,the unidirectional FT condition,which is also prevalent in engineering practice,has received limited attention.Therefore,a comparative study on frost deformation and microstructure evolution of porous rock under both uniform and unidirectional FT conditions was performed.Firstly,frost deformation experiments of rock were conducted under cyclic uniform and unidirectional FT action,respectively.Results illustrate that frost deformation of saturated rock exhibits isotropic characteristics under uniform FT cycles,while it shows anisotropic characteristics under unidirectional FT condition with both the frost heaving strain and residual strain along FT direction much higher than those perpendicular to FT direction.Moreover,the peak value and residual value of cumulative frost strain vary as logarithmic functions with cycle number under both uniform and unidirectional FT conditions.Subsequently,the microstructure evolution of rock suffered cyclic uniform and unidirectional FT action were measured.Under uniform FT cycles,newly generated pores uniformly distribute in rock and pore structure of rock remains isotropic in micro scale,and thus the frost deformation shows isotropic characteristics in macro scale.Under unidirectional FT cycles,micro-cracks or pore belts generate with their orientation nearly perpendicular to the FT direction,and rock structure gradually becomes anisotropic in micro scale,resulting in the anisotropic characteristics of frost deformation in macro scale. 展开更多
关键词 Frost deformation Microstructure evolution Porous rock Unidirectional freeze-thaw cycles Uniform freeze-thaw cycles
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Fractal Study on the Evolution of Micro-Pores in Concrete Under Freeze-Thaw
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作者 孙浩然 邹春霞 +2 位作者 XU Deru GUO Xiaosong HUANG Kun 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期109-117,共9页
After exposure to freeze-thaw cycles, scanning electron microscopy(SEM) and nuclear magnetic resonance(NMR) were used to test the four mixtures. The microstructure is qualitatively analyzed from the 2D SEM image and t... After exposure to freeze-thaw cycles, scanning electron microscopy(SEM) and nuclear magnetic resonance(NMR) were used to test the four mixtures. The microstructure is qualitatively analyzed from the 2D SEM image and the 3D pore distribution curve before and after freezing and thawing. The fractal dimension is utilized to characterize the two-dimensional topography image and the three-dimensional pore distribution, quantitatively. The results reveal that the surface porosity and volume porosity increase as the freeze-thaw action increases. Self-similarity characteristics exist in micro-damage inside the concrete. In the fractal dimension, it is possible to characterize pore evolution quantitatively. The fractal dimension correlates with pore damage evolution. The fractal dimension effectively quantitatively characterizes micro-damage features at various scales from the local to the global level. 展开更多
关键词 fractal dimension freeze-thaw cycle CONCRETE SEM NMR
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Freeze-thaw cycles and associated geomorphology in a post-glacial environment:current glacial,paraglacial,periglacial and proglacial scenarios at Pico de Orizaba volcano,Mexico
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作者 Víctor SOTO Carlos M.WELSH R. +1 位作者 Kenji YOSHIKAWA Hugo DELGADO GRANADOS 《Journal of Mountain Science》 SCIE CSCD 2024年第6期1954-1977,共24页
The glacial history of Pico de Orizaba indicates that during the Last Glacial Maximum,its icecap covered up to~3000 m asl;due to the air temperature increasing,its main glacier has retreated to 5050 m asl.The retracti... The glacial history of Pico de Orizaba indicates that during the Last Glacial Maximum,its icecap covered up to~3000 m asl;due to the air temperature increasing,its main glacier has retreated to 5050 m asl.The retraction of the glacier has left behind an intense climatic instability that causes a high frequency of freeze-thaw cycles of great intensity;the resulting geomorphological processes are represented by the fragmentation of the bedrock that occupies the upper parts of the mountain.There is a notable lack of studies regarding the fragmentation and erosion occurring in tropical high mountains,and the associated geomorphological risks;for this reason,as a first stage of future continuous research,this study analyzes the freezing and thawing cycles that occur above 4000 m asl,through continuous monitoring of surface ground temperature.The results allow us to identify and characterize four zones:glacial,paraglacial,periglacial and proglacial.It was found that the paraglacial zone presents an intense drop of temperature,of up to~9℃ in only sixty minutes.The rock fatigue and intense freeze-thaw cycles that occur in this area are responsible for the high rate of rock disintegration and represent the main factor of the constant slope dynamics that occur at the site.This activity decreases,both in frequency and intensity,according to the distance to the glacier,which is where the temperature presents a certain degree of stability,until reaching the proglacial zone,where cycles are almost non-existent,and therefore there is no gelifraction activity.The geomorphological processes have resulted in significant alterations to the mountain slopes,which can have severe consequences in terms of risk and water. 展开更多
关键词 freeze-thaw Gelifraction Mountain mechanical erosion Periglacial geomorphology Postglacial scenarios
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Predicting uniaxial compressive strength of tuff after accelerated freeze-thaw testing: Comparative analysis of regression models and artificial neural networks
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作者 Ogün Ozan VAROL 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3521-3535,共15页
Ignimbrites have been widely used as building materials in many historical and touristic structures in the Kayseri region of Türkiye. Their diverse colours and textures make them a popular choice for modern const... Ignimbrites have been widely used as building materials in many historical and touristic structures in the Kayseri region of Türkiye. Their diverse colours and textures make them a popular choice for modern construction as well. However, ignimbrites are particularly vulnerable to atmospheric conditions, such as freeze-thaw cycles, due to their high porosity, which is a result of their formation process. When water enters the pores of the ignimbrites, it can freeze during cold weather. As the water freezes and expands, it generates internal stress within the stone, causing micro-cracks to develop. Over time, repeated freeze-thaw (F-T) cycles lead to the growth of these micro-cracks into larger cracks, compromising the structural integrity of the ignimbrites and eventually making them unsuitable for use as building materials. The determination of the long-term F-T performance of ignimbrites can be established after long F-T experimental processes. Determining the long-term F-T performance of ignimbrites typically requires extensive experimental testing over prolonged freeze-thaw cycles. To streamline this process, developing accurate predictive equations becomes crucial. In this study, such equations were formulated using classical regression analyses and artificial neural networks (ANN) based on data obtained from these experiments, allowing for the prediction of the F-T performance of ignimbrites and other similar building stones without the need for lengthy testing. In this study, uniaxial compressive strength, ultrasonic propagation velocity, apparent porosity and mass loss of ignimbrites after long-term F-T were determined. Following the F-T cycles, the disintegration rate was evaluated using decay function approaches, while uniaxial compressive strength (UCS) values were predicted with minimal input parameters through both regression and ANN analyses. The ANN and regression models created for this purpose were first started with a single input value and then developed with two and three combinations. The predictive performance of the models was assessed by comparing them to regression models using the coefficient of determination (R2) as the evaluation criterion. As a result of the study, higher R2 values (0.87) were obtained in models built with artificial neural network. The results of the study indicate that ANN usage can produce results close to experimental outcomes in predicting the long-term F-T performance of ignimbrite samples. 展开更多
关键词 IGNIMBRITE Uniaxial compressive strength freeze-thaw Decay function Regression Artificial neural network
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Effect of sodium starch octenyl succinate-based Pickering emulsion on the physicochemical properties of hairtail myofibrillar protein gel subjected to multiple freeze-thaw cycles
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作者 Huinan Wang Jiaxin Zhang +3 位作者 Xinran Liu Jinxiang Wang Xuepeng Li Jianrong Li 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期1018-1028,共11页
A Pickering emulsion based on sodium starch octenyl succinate(SSOS)was prepared and its effects on the physicochemical properties of hairtail myofibrillar protein gels(MPGs)subjected to multiple freeze-thaw(F-T)cycles... A Pickering emulsion based on sodium starch octenyl succinate(SSOS)was prepared and its effects on the physicochemical properties of hairtail myofibrillar protein gels(MPGs)subjected to multiple freeze-thaw(F-T)cycles were investigated.The whiteness,water-holding capacity,storage modulus(G')and texture properties of the MPGs were significantly improved by adding 1%-2%Pickering emulsion(P<0.05).Meanwhile,Raman spectral analysis demonstrated that Pickering emulsion promoted the transformation of secondary structure,enhanced hydrogen bonds and hydrophobic interactions,and promoted the transition of disulfide bond conformation from g-g-g to g-g-t and t-g-t.At an emulsion concentration of 2%,theα-helix content decreased by 10.37%,while theβ-sheet content increased by 7.94%,compared to the control.After F-T cycles,the structure of the MPGs was destroyed,with an increase in hardness and a decrease in whiteness and water-holding capacity,however,the quality degradation of MPGs was reduced with 1%-2%Pickering emulsion.These findings demonstrated that SSOS-Pickering emulsions,as potential fat substitutes,can enhance the gel properties and the F-T stability of MPGs. 展开更多
关键词 Pickering emulsion Myofibrillar protein Gel properties freeze-thaw stability Intermolecular interactions
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Analysis of the Higher Education Research in the Chengdu-Chongqing Region:A Comparative Perspective Based on Three Major Economic Circles in China
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作者 Dai Rui Luo Hong Xie Xiaoli 《Contemporary Social Sciences》 2023年第1期102-115,共14页
Drawing on literature regarding higher education research retrieved from the CNKI database from 1997 to 2021,this paper used CiteSpace to analyze the current status of higher education research in the Chengdu-Chongqin... Drawing on literature regarding higher education research retrieved from the CNKI database from 1997 to 2021,this paper used CiteSpace to analyze the current status of higher education research in the Chengdu-Chongqing economic circle.By comparing it with that in the Beijing-Tianjin-Hebei region,the Guangdong-Hong Kong-Macao Greater Bay Area,and the Yangtze River Delta,this paper concluded that the level of higher education research within a region is in line with the level of the region’s economic and social development.As higher education research in the Chengdu-Chongqing economic circle draws more and more attention,its research areas and topics are becoming increasingly diversified.However,by comparison,the research in this region features a late start and lower participation of researchers and research institutions,resulting in insufficient research in both quantity and quality.Therefore,it is essential to encourage more experts and scholars to participate in higher education research in the Chengdu-Chongqing economic circle.Efforts should also be made to strengthen academic exchanges and cooperation between scholars in Chengdu and Chongqing and establish a long-term cooperation mechanism for higher education research between the two cities.Improved higher education research will definitely facilitate the construction of first-class universities,thus providing human capital and intellectual support for the construction of the Chengdu-Chongqing economic circle. 展开更多
关键词 higher education research Chengdu-Chongqing economic circle Beijing-Tianjin-Hebei region Guangdong-Hong Kong-Macao Greater Bay Area Yangtze River Delta
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Surrounding rock pressure in the tunnel portal section through moraine under freeze-thaw action
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作者 CHEN Zhimin LIU Baoli +1 位作者 LIU Yaohui XU Jiangtao 《Journal of Mountain Science》 SCIE CSCD 2024年第7期2480-2493,共14页
Moraines,characterized by the accumulation of rock and soil debris transported by glacial activity,present unique challenges for tunnel construction,particularly in portal sections,due to prevailing geographical and c... Moraines,characterized by the accumulation of rock and soil debris transported by glacial activity,present unique challenges for tunnel construction,particularly in portal sections,due to prevailing geographical and climatic conditions that facilitate freeze-thaw action.Despite these challenges,there is a dearth of studies investigating the influence of freeze-thaw action and water content on the mechanical properties of moraines,and no research on calculating surrounding rock pressure in moraine tunnels subjected to freeze-thaw conditions.In this study,direct shear tests under freeze-thaw cycles were conducted to examine the effects of freeze-thaw cycles and water content on the mechanical properties of frozen moraine.A comprehensive parameter K,integrating the number of freeze-thaws and water content,was introduced to model cohesion c.Drawing on Terzaghi Theory,we propose an improved algorithm for calculating surrounding rock pressure at the portal section of moraine tunnels.Using a tunnel as a case study,surrounding rock pressure was calculated under various conditions to validate the Improved Algorithm's efficacy.The results show that:(1)Strength loss exhibits a linear trend with the number of freeze-thaw cycles at water content levels of 4%and 8%,while at 12%water content,previous freeze-thaw cycles induce more significant damage to the soil.(2)Moraine saturation peaks between 8%and 12%water content.Following repeated freeze-thaw cycles,moraine shear strength initially increases before decreasing with varying water content.(3)The internal friction angle of moraine experiences slight reductions with prolonged freeze-thaw cycles,but both freeze-thaw cycles and water content significantly influence cohesion.(4)Vertical surrounding rock pressure increases after the initial freeze-thaw cycle,particularly with higher water content,although freeze-thaw cycles have minimal effect on it.(5)Freeze-thaw cycles lead to a substantial increase in lateral surrounding rock pressure,necessitating reinforced support structures at the arch wall,arch waist,and arch foot in engineering projects to mitigate freeze-thaw effects.This study provides a foundation for designing and selecting tunnel support structures in similar geological conditions. 展开更多
关键词 MORAINES freeze-thaw cycles Direct shear test Surrounding rock pressure
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Coupling Effect of Cryogenic Freeze-Thaw Cycles and Chloride Ion Erosion Effect in Pre-Cracked Reinforced Concrete
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作者 Yang Li Sibo Jiang Ruixin Lan 《Structural Durability & Health Monitoring》 EI 2024年第3期255-276,共22页
Chloride (Cl−) ion erosion effects can seriously impact the safety and service life of marine liquefied natural gas(LNG) storage tanks and other polar offshore structures. This study investigates the impact of differe... Chloride (Cl−) ion erosion effects can seriously impact the safety and service life of marine liquefied natural gas(LNG) storage tanks and other polar offshore structures. This study investigates the impact of different low-temperaturecycles (20°C, –80°C, and −160°C) and concrete specimen crack widths (0, 0.3, and 0.6 mm) on the Cl−ion diffusion performance through rapid erosion tests conducted on pre-cracked concrete. The results show thatthe minimum temperature and crack width of freeze-thaw cycles enhance the erosive effect of chloride ions. TheCl− ion concentration and growth rate increased with the increasing crack width. Based on the experimental modeland in accordance with Fick’s second law of diffusion, the Cl− ion diffusion equation was modified by introducingcorrection factors in consideration of the freeze-thaw temperature, crack width, and their coupling effect.The experimental and fitting results obtained from this model can provide excellent reference for practical engineeringapplications. 展开更多
关键词 Chloride ions freeze-thaw cycles cracks
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Experimental study on the movement of oil spill under freeze-thaw action
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作者 ZeLiang Ye JianGuo Lu +2 位作者 MingYi Zhang WanSheng Pei ShuTong Li 《Research in Cold and Arid Regions》 CSCD 2024年第3期111-120,共10页
Oil leakages cause environmental pollution,economic losses,and even engineering safety accidents.In cold regions,researchers urgently investigate the movement of oil spill in soils exposed to freeze-thaw cycles.In thi... Oil leakages cause environmental pollution,economic losses,and even engineering safety accidents.In cold regions,researchers urgently investigate the movement of oil spill in soils exposed to freeze-thaw cycles.In this study,a series of laboratory model experiments were carried out on the migration of oil leakage under freeze-thaw action,and the distributions of the soil temperature,unfrozen water content,and displacement were analyzed.The results showed that under freeze-thaw action,liquid water in soils migrated to the freezing front and accumulated.After the pipe cracked,oil pollutants first gathered at one side of the leak hole,and then moved around.The pipe wall temperature affected the soil temperature field,and the thermal influence range below and transverse the pipe wall(35–40 cm)was larger than that above the pipe wall(8 cm)owing to the soil surface temperature.The leaked oil's temperature would make the temperature of the surrounding soil rise.Oil would inhibit the cooling of the soils.Besides,oil migration was significantly affected by the gravity and water flow patterns.The freeze-thaw action would affect the migration of the oil,which was mainly manifested as inhibiting the diffusion and movement of oil when soils were frozen.Unfrozen water transport caused by freeze-thaw cycles would also inhibit oil migration.The research results would provide a scientific reference for understanding the relationship between the movement of oil pollutants,water,and soil temperature,and for establishing a waterheat-mass transport model in frozen soils. 展开更多
关键词 freeze-thaw action Oil movement Soil temperature Unfrozen water content Model test
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Repair of Second-Generation Recycled Fine Aggregate of Waste Concrete from Freeze-Thaw Environment by Carbonation Treatment
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作者 Jie Huang Rongbin Jiang +1 位作者 Xiaobo Sun Yingyong Shuai 《Journal of Renewable Materials》 EI CAS 2024年第1期187-201,共15页
The reuse of waste recycled concrete from harsh environments has become a research hotspot in the field of construction.This study investigated the repair effect of carbonation treatment on second-generation recycled ... The reuse of waste recycled concrete from harsh environments has become a research hotspot in the field of construction.This study investigated the repair effect of carbonation treatment on second-generation recycled fine aggregate(SRFA)obtained from recycled fine aggregate concrete(RFAC)subjected to freeze-thaw(FT)cycles.Before and after carbonation,the properties of SRFA were evaluated.Carbonated second-generation recycled fine aggregate(CSRFA)at five substitution rates(0%,25%,50%,75%,100%)to replace SRFA was used to prepare carbonated second-generation recycled fine aggregate concrete(CSRFAC).The water absorption,porosity and mechanical properties of CSRFAC were tested,and its frost-resisting durability was evaluated.The results showed after carbonation treatment,the physical properties of SRFA was improved and met the requirements of II aggregate.The micro-hardness of the interfacial transition zone and attached mortar in CSRFA was 50.5%and 31.2%higher than that in SRFA,respectively.With the increase of CSRFA replacement rate,the water absorption and porosity of CSRFAC gradually decreased,and the mechanical properties and frost resistance of CSRFAC were gradually improved.Carbonation treatment effectively repairs the damage of SRFA caused by FT cycles and improves its application potential. 展开更多
关键词 Carbonation treatment REPAIR freeze-thaw cycles second-generation recycled fine aggregate
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Spatiotemporal variation and freeze-thaw asymmetry of Arctic sea ice in multiple dimensions during 1979 to 2020
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作者 Yu Guo Xiaoli Wang +1 位作者 He Xu Xiyong Hou 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期102-114,共13页
Arctic sea ice is broadly regarded as an indicator and amplifier of global climate change.The rapid changes in Arctic sea ice have been widely concerned.However,the spatiotemporal changes in the horizontal and vertica... Arctic sea ice is broadly regarded as an indicator and amplifier of global climate change.The rapid changes in Arctic sea ice have been widely concerned.However,the spatiotemporal changes in the horizontal and vertical dimensions of Arctic sea ice and its asymmetry during the melt and freeze seasons are rarely quantified simultaneously based on multiple sources of the same long time series.In this study,the spatiotemporal variation and freeze-thaw asymmetry of Arctic sea ice were investigated from both the horizontal and vertical dimensions during 1979–2020 based on remote sensing and assimilation data.The results indicated that Arctic sea ice was declining at a remarkably high rate of–5.4×10^(4) km^(2)/a in sea ice area(SIA)and–2.2 cm/a in sea ice thickness(SIT)during 1979 to 2020,and the reduction of SIA and SIT was the largest in summer and the smallest in winter.Spatially,compared with other sub-regions,SIA showed a sharper declining trend in the Barents Sea,Kara Sea,and East Siberian Sea,while SIT presented a larger downward trend in the northern Canadian Archipelago,northern Greenland,and the East Siberian Sea.Regarding to the seasonal trend of sea ice on sub-region scale,the reduction rate of SIA exhibited an apparent spatial heterogeneity among seasons,especially in summer and winter,i.e.,the sub-regions linked to the open ocean exhibited a higher decline rate in winter;however,the other sub-regions blocked by the coastlines presented a greater decline rate in summer.For SIT,the sub-regions such as the Beaufort Sea,East Siberian Sea,Chukchi Sea,Central Arctic,and Canadian Archipelago always showed a higher downward rate in all seasons.Furthermore,a striking freeze-thaw asymmetry of Arctic sea ice was also detected.Comparing sea ice changes in different dimensions,sea ice over most regions in the Arctic showed an early retreat and rapid advance in the horizontal dimension but late melting and gradual freezing in the vertical dimension.The amount of sea ice melting and freezing was disequilibrium in the Arctic during the considered period,and the rate of sea ice melting was 0.3×10^(4) km^(2)/a and 0.01 cm/a higher than that of freezing in the horizontal and vertical dimensions,respectively.Moreover,there were notable shifts in the melting and freezing of Arctic sea ice in 1997/2003 and 2000/2004,respectively,in the horizontal/vertical dimension. 展开更多
关键词 Arctic sea ice sea ice area sea ice thickness spatiotemporal variation freeze-thaw asymmetry
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Comprehensive evaluation and spatial-temporal evolution characteristics of urban resilience in Chengdu-Chongqing Economic Circle
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作者 Xin Li Shuyi Zhang +1 位作者 Rongxi Ren Yafei Wang 《Chinese Journal of Population,Resources and Environment》 2024年第1期58-67,共10页
To clarify the connotations and extensions of urban resilience,this study focuses on the Chengdu-Chongqing Economic Circle with 16 cities as research subjects.A comprehensive evaluation index system was constructed to... To clarify the connotations and extensions of urban resilience,this study focuses on the Chengdu-Chongqing Economic Circle with 16 cities as research subjects.A comprehensive evaluation index system was constructed to measure the resilience of each city from 2003 to 2020.The spatial-temporal evolution characteristics were analyzed using Kernel density estimation,standard deviation ellipse,and spatial Markov chain analysis,and the spatial Tobit model was introduced to discover the influencing factors.The results indicate the following:①Urban resilience in the Chengdu-Chongqing Economic Circle displays an upward trend,with the center of gravity moving to the southwest,and the polarization phenomenon intensifying.②The urban resilience level in a region has certain spatial and geographical dependence,while the probability of urban resilience transfer differs in adjacent cities with different resilience levels.③Urban centrality,economic scale,openness level,and financial development promote urban resilience,whereas government scale significantly inhibits it.Finally,this paper proposes countermeasures and suggestions to improve the urban resilience of the Chengdu-Chongqing Economic Circle. 展开更多
关键词 Chengdu-chongqing Economic circle Urban resilience Spatial-temporal evolution Driving factor
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Research on the Evolution Structure of Fragment Disordering Public Opinion in College Students’ Network Circle Group
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作者 Huawei Zhi Yan Qiao 《Social Networking》 2024年第4期45-65,共21页
Clarifying the evolution structure of public opinion induced and spread by fragmentation in college students’ network circle group is the key to understanding college students’ online social psychological demands, g... Clarifying the evolution structure of public opinion induced and spread by fragmentation in college students’ network circle group is the key to understanding college students’ online social psychological demands, grasping the development trend of public opinion, and designing targeted public opinion governance strategies. On the basis of identifying the key variables in the process of public opinion communication, DEMATEL-ISM model is used to explore the attribute positioning, relative importance level and hierarchical association mechanism of ante-variable and result variable, and then the governance strategies for fragment disordering public opinion in network circle groups of college students is designed. According to the study, exogenous stimuli, the uniqueness of discourse system, the number of spectacular texts and micro-narrative mode constituted the deep-rooted causes of fragment disordering public opinion. The unique situational and information attributes of network circle groups often become an important “booster” of disordered public opinion. The topic deviation is often accompanied with the formation of negative emotions. The corresponding public opinion governance strategies are sought from the aspects of shaping the network environment, adjusting the operation mechanism of the network circle group, improving the efficiency of using fragmented information, and optimizing the human resources of colleges. 展开更多
关键词 College Students’ Network circle Group Fragment Disordering Public Opinion Governance DEMATEL ISM
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The Impact of Digital Finance on High-Quality Development of the Chengdu-Chongqing Economic Circle
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作者 Wei Liangyi Bai Xiaobo Li Qin 《Contemporary Social Sciences》 2024年第2期1-15,共15页
This paper developed a comprehensive evaluation system that was able to quantify the levels of high-quality development across the cities within the Chengdu-Chongqing economic circle,and investigate the impact that di... This paper developed a comprehensive evaluation system that was able to quantify the levels of high-quality development across the cities within the Chengdu-Chongqing economic circle,and investigate the impact that digital finance had on the cities’high-quality development and the underlying mechanisms through which it achieved this.This comprehensive evaluation system was constructed using statistical data from these cities for the period 2014 to 2020 while also taking China’s high-quality development philosophy into account.The key findings revealed that:(a)Digital finance was able to significantly promote high-quality development in the Chengdu-Chongqing economic circle;(b)Digital finance had a significant positive effect in promoting innovative,coordinated,green,open,and shared development;(c)Digital finance was able to stimulate the high-quality development in the Chengdu-Chongqing economic circle by boosting entrepreneurial dynamism;(d)Digital finance had a significant impact on the high-quality development of the axis areas,while its impact was less discernible in non-axis areas.The insights from this research offer a deeper understanding of the factors that drive high-quality development,the role digital finance plays,and the mechanisms through which digital finance is able to propel high-quality development at the city cluster scale. 展开更多
关键词 digital finance Chengdu-Chongqing economic circle high-quality development
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Coupling coordinated development among digital economy,regional innovation,and talent employment:A case study in the Hangzhou Metropolitan Circle,China
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作者 QIU Luyi Sharina OSMAN HUA Yidi 《Regional Sustainability》 2024年第1期93-106,共14页
Coordinative development across various systems,particularly the economic,social,cultural,and human resources subsystems,is a key aspect of urban sustainability and has a direct impact on the quality of urbanization.T... Coordinative development across various systems,particularly the economic,social,cultural,and human resources subsystems,is a key aspect of urban sustainability and has a direct impact on the quality of urbanization.The Hangzhou Metropolitan Circle,comprising Hangzhou City,Huzhou City,Jiaxing City,and Shaoxing City,was the first metropolitan circle approved by the National Development and Reform Commission(NDRC)as a demonstration of economic transformation in China.To evaluate the coupling coordination degree of the four cities and analyze the coordinative development in three systems(including digital economy,regional innovation,and talent employment),we collected panel data during 2015–2022 from these four cities.The development level of the three systems was evaluated by the standard deviation method and comprehensive development index.The results are as follows:(1)the level of coupling coordinated development of the three systems in the Hangzhou Metropolitan Circle was relatively low;(2)the coupling coordination degree of the four cities in the Hangzhou Metropolitan Circle showed significant regional differences,among which Hangzhou City was in the leading position,and Huzhou,Jiaxing,and Shaoxing cities made steady but slow progress in the coupling development of the three systems;and(3)the development of digital economy and talent employment needs to be strengthened.This study contributes to the coordinative development of Hangzhou Metropolitan Circle by innovatively focusing on the coupling coordination relationship among digital economy,regional innovation,and talent employment,which also meets the industrial layout of Hangzhou Metropolitan Circle.In this way,the optimal allocation and sustainable development of digital economy,regional innovation,and talent employment in the Hangzhou Metropolitan Circle can be achieved. 展开更多
关键词 Digital economy Regional innovation Talent employment Coupling coordination degree Hangzhou Metropolitan circle
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Identification and Optimisation of Cycling Life Circle in High Density Communities with Public Health Support: A Case Study of Tiantongyuan in Beijing
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作者 LIANG Weinan HUANG Yi +1 位作者 WANG Zilin ZHOU Xuan 《Journal of Landscape Research》 2024年第5期27-32,37,共7页
In recent years,the compact development of high-density cities has sparked ongoing interest in healthy urban environments and public well-being.This study examines the relationship between cycling behaviors and the bu... In recent years,the compact development of high-density cities has sparked ongoing interest in healthy urban environments and public well-being.This study examines the relationship between cycling behaviors and the built environment of streets in Tiantongyuan Community,a typical high-density area in Beijing,China.By observing street spaces and summarizing residents’travel modes and behaviors,the study evaluates the impact of street design on cycling habits.In order to reveal the riding behavior characteristics of residents in different time periods and different street spaces,tools such as track recording APPs and the Gopro Motion Camera are employed to collect street view pictures and riding track data comprehensively,analyzing the various travel purposes of residents in Tiantongyuan community and the riding OD activity tracks of the main entrances and exits of the community.Meanwhile,by conducting the questionnaire survey of residents’travel demands and OD data of Baidu,and utilizing geographic information system(GIS)for data visualization,this study further investigates the distribution characteristics of cycling hotspots,cycling paths and cycling space,accurately identifies the cycling life circle of this community based on the spatial and temporal scales,and further puts forward the optimization strategy of the cycling network.Some cycling-friendly street space optimization strategies are suggested to deeply analyze the mechanism of the built environment of street space in high-density communities on the cycling activities and health of urban residents,with a view to provide accurate data support for the renewal of street cycling space. 展开更多
关键词 Public health High-density neighbourhoods Cycling life circle Precision update Tiantongyuan community
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