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Reconstructed organic rice fields:Effects on soil organic carbon,total nitrogen,their mineralization,and rice yield in Japanese Andosols
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作者 Valensi Kautsar Takamori Kanno +5 位作者 Kaho Sakai Riza Kurnia Sabri Keitaro Tawaraya Kazunobu Toriyama Kazuhiko Kobayashi Weiguo Cheng 《Journal of Integrative Agriculture》 2026年第2期493-500,共8页
To examine the impact of anthropogenic land reconstruction,particularly the consolidation of small terraces into larger fields,on soil organic carbon(SOC),total nitrogen(TN)dynamics,rice yield,and its components,soil ... To examine the impact of anthropogenic land reconstruction,particularly the consolidation of small terraces into larger fields,on soil organic carbon(SOC),total nitrogen(TN)dynamics,rice yield,and its components,soil and plant samples were collected from seven newly reconstructed fields in Japanese Andosols in Tochigi,Japan.Samples were obtained from both the former low-and high-elevation sides within each field plot.During harvest season,nine rice plants were randomly selected from each plot(0.675 m^(2),comprising 3 rows and 3 hills per row),collected from a 3-m stretch along both the east(former low side)and west(former high side)ridges.Soil cores were collected from identical plots at two depths(0–15 and 15–30 cm)and combined into one composite sample per layer.Rice plant samples were air-dried for two weeks until reaching constant moisture content,after which stems and ears were separated and weighed to determine biomass,yield,yield components,and nitrogen uptake.This indicated that land reconstruction significantly affected rice yield and its components between the two sides of all field plots.SOC,TN,and their decomposition following land reconstruction showed notable changes,especially in the 15–30 cm subsurface soil layer.Additionally,grain weight demonstrated significant correlation with SOC,TN,and carbon decomposition in both the 0–15 and 15–30 cm layers,indicating that soil fertility to a depth of 30 cm was crucial for rice productivity after land reconstruction. 展开更多
关键词 Japanese Andosols different soil layers organic rice farming reconstructed fields rice yield
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Study on dynamic similarity of elastic shell during water entry
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作者 Haisu Liu Fei Xu +4 位作者 Xinzhe Chang Yang Yang Xiaocheng Li Xiaochuan Liu Wei Feng 《Acta Mechanica Sinica》 2026年第1期233-250,共18页
In the study of thin-walled wedge shells subjected to lateral water entry impact loads,similarity theory is employed to predict the behavior of the prototype by analyzing the dynamic response of the model.However,the ... In the study of thin-walled wedge shells subjected to lateral water entry impact loads,similarity theory is employed to predict the behavior of the prototype by analyzing the dynamic response of the model.However,the traditional similarity law for structural impact fails to accurately describe the relationship between the dynamic responses of the model and the prototype,mainly due to the ignoring of the fluid-structure coupling effect and geometric distortion in the thickness direction.To address this limitation,this study employs dimensional analysis to derive the scaling factors for achieving structural similarity during water entry while considering the effects of fluid-structure coupling.Based on the analysis of the governing equations for thin-walled wedge shells under water entry impact loads,the scaling factor accounting for geometric distortion for water entry of wedge shells is determined.Numerical models are established to verify the applicability of the geometric distortion similarity model with different materials.The results demonstrate the effectiveness of the proposed similarity model,which significantly reduces the disparities in displacement peaks and energy between the scaled model and the prototype.In addition,experimental platforms are constructed to further verify the proposed similarity model by performing vertical water entry tests on thickness-distorted and material-distorted specimens. 展开更多
关键词 Water entry impact Dimensional analysis Similarity theory Different materials Fluid-structure interaction
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Cell therapy rejuvenates the neuroglial-vascular unit
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作者 Bandy Chen 《Neural Regeneration Research》 2026年第4期1542-1543,共2页
The rise of the aging population parallels the rapidly increasing cases of neurological disorders. This puts pressure on scientists and physicians to find novel methods that can prevent and treat neurodegeneration. Th... The rise of the aging population parallels the rapidly increasing cases of neurological disorders. This puts pressure on scientists and physicians to find novel methods that can prevent and treat neurodegeneration. The brain is made up of a complex network of different cell types that work in tandem to maintain systemic homeostasis. 展开更多
关键词 maintain systemic homeostasis prevent treat neurodegeneration cell therapy neurological disorders neuroglial vascular unit network different cell types NEURODEGENERATION aging population
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Experimental Study of Hydraulic–Natural Fracture Interactions under Variable Geomechanical Conditions in Deep Shale of the Southern Sichuan Basin
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作者 Bo Zeng Junfeng Li +4 位作者 Liqing Chen Qiyong Gou Hao Luo Haiyan Zhu Xuanhe Tang 《Fluid Dynamics & Materials Processing》 2026年第2期265-277,共13页
Deep shale gas reservoirs in the southern Sichuan Basin are typically characterized by significant horizontal stress anisotropy(expressed as stress difference),variable brittleness-ductility in rock mechanics,and stro... Deep shale gas reservoirs in the southern Sichuan Basin are typically characterized by significant horizontal stress anisotropy(expressed as stress difference),variable brittleness-ductility in rock mechanics,and strong heterogeneity.These complex geomechanical conditions lead to pronounced differences in hydraulic fracturing outcomes among wells and sections.To investigate hydraulic fracture propagation and fracturing fluid injection behavior under varying geomechanical settings,true triaxial physical simulation tests were performed on 400×400×400 mm artificial rock samples.The samples were designed with different media properties based on similarity criteria.A sensitivity analysis was conducted to assess the effects of brittleness-ductility characteristics,natural fractures,and in-situ stress conditions.The results reveal that:(i)brittle samples with lower stress difference are favorable for forming complex,perforable fracture networks;(ii)brittle samples with higher stress difference tend to develop simple,planar hydraulic fractures,with natural fractures only slightly activated during very short injection periods;(iii)ductile behavior enhances the activation of natural fractures but reduces fracture complexity compared with brittle samples,even under lower stress difference;and(iv)for typical deep shale formations,larger fluid injection volumes combined with high-density,multi-cluster fracturing techniques are recommended. 展开更多
关键词 Deep shale in the southern Sichuan basin hydraulic fracturing fracture propagation true triaxial physical simulation tests typical different geomechanics
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Role and mechanisms of histone methylation in osteogenic/odontogenic differentiation of dental mesenchymal stem cells 被引量:2
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作者 Meijun Hu Zhipeng Fan 《International Journal of Oral Science》 2025年第3期341-360,共20页
Dental mesenchymal stem cells(DMSCs)are pivotal for tooth development and periodontal tissue health and play an important role in tissue engineering and regenerative medicine because of their multidirectional differen... Dental mesenchymal stem cells(DMSCs)are pivotal for tooth development and periodontal tissue health and play an important role in tissue engineering and regenerative medicine because of their multidirectional differentiation potential and self-renewal ability.The cellular microenvironment regulates the fate of stem cells and can be modified using various optimization techniques.These methods can influence the cellular microenvironment,activate disparate signaling pathways,and induce different biological effects.“Epigenetic regulation”refers to the process of influencing gene expression and regulating cell fate without altering DNA sequences,such as histone methylation.Histone methylation modifications regulate pivotal transcription factors governing DMSCs differentiation into osteo-/odontogenic lineages.The most important sites of histone methylation in tooth organization were found to be H3K4,H3K9,and H3K27.Histone methylation affects gene expression and regulates stem cell differentiation by maintaining a delicate balance between major trimethylation sites,generating distinct chromatin structures associated with specific downstream transcriptional states.Several crucial signaling pathways associated with osteogenic differentiation are susceptible to modulation via histone methylation modifications.A deeper understanding of the regulatory mechanisms governing histone methylation modifications in osteo-/odontogenic differentiation and immune-inflammatory responses of DMSCs will facilitate further investigation of the epigenetic regulation of histone methylation in DMSC-mediated tissue regeneration and inflammation.Here is a concise overview of the pivotal functions of epigenetic histone methylation at H3K4,H3K9,and H3K27 in the regulation of osteo-/odontogenic differentiation and renewal of DMSCs in both non-inflammatory and inflammatory microenvironments.This review summarizes the current research on these processes in the context of tissue regeneration and therapeutic interventions. 展开更多
关键词 tooth development stem cells tissue engineering influence cellular microenvironmentactivate disparate signaling pathwaysand induce different biological effec regenerative medicine cellular microenvironment dental mesenchymal stem cells dmscs
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Dynamic Route Optimization for Multi-Vehicle Systems with Diverse Needs in Road Networks Based on Preference Games 被引量:1
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作者 Jixiang Wang Jing Wei +2 位作者 Siqi Chen Haiyang Yu Yilong Ren 《Computers, Materials & Continua》 2025年第6期4167-4192,共26页
The real-time path optimization for heterogeneous vehicle fleets in large-scale road networks presents significant challenges due to conflicting traffic demands and imbalanced resource allocation.While existing vehicl... The real-time path optimization for heterogeneous vehicle fleets in large-scale road networks presents significant challenges due to conflicting traffic demands and imbalanced resource allocation.While existing vehicleto-infrastructure coordination frameworks partially address congestion mitigation,they often neglect priority-aware optimization and exhibit algorithmic bias toward dominant vehicle classes—critical limitations in mixed-priority scenarios involving emergency vehicles.To bridge this gap,this study proposes a preference game-theoretic coordination framework with adaptive strategy transfer protocol,explicitly balancing system-wide efficiency(measured by network throughput)with priority vehicle rights protection(quantified via time-sensitive utility functions).The approach innovatively combines(1)a multi-vehicle dynamic routing model with quantifiable preference weights,and(2)a distributed Nash equilibrium solver updated using replicator sub-dynamic models.The framework was evaluated on an urban road network containing 25 intersections with mixed priority ratios(10%–30%of vehicles with priority access demand),and the framework showed consistent benefits on four benchmarks(Social routing algorithm,Shortest path algorithm,The comprehensive path optimisation model,The emergency vehicle timing collaborative evolution path optimization method)showed consistent benefits.Results showthat across different traffic demand configurations,the proposed method reduces the average vehicle traveling time by at least 365 s,increases the road network throughput by 48.61%,and effectively balances the road loads.This approach successfully meets the diverse traffic demands of various vehicle types while optimizing road resource allocations.The proposed coordination paradigm advances theoretical foundations for fairness-aware traffic optimization while offering implementable strategies for next-generation cooperative vehicle-road systems,particularly in smart city deployments requiring mixed-priority mobility guarantees. 展开更多
关键词 Preference game vehicle road coordination large-scale road network different needs dynamic route selection
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Geriatric assessment for predicting outcomes among patients with aortic stenosis undergoing transcatheter aortic valve implantation 被引量:1
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作者 Calvo E Castillo P +10 位作者 Romaguera R Llaó I Zafrilla R Domene G Alegre O Lorente V Muntané-Carol G Formiga F de la Cuerda FJ Gomez Hospital JA Ariza-Solè A 《Journal of Geriatric Cardiology》 2025年第5期516-524,共9页
Background There is scarce data about comparisons between geriatric assessment tools in patients with aortic stenosis(AS).We aimed to describe the geriatric profile of patients with AS undergoing transcatheter aortic ... Background There is scarce data about comparisons between geriatric assessment tools in patients with aortic stenosis(AS).We aimed to describe the geriatric profile of patients with AS undergoing transcatheter aortic valve implantation(TAVI)and to analyze the ability of different tools for predicting clinical outcomes in this context.Methods This was a single center retrospective registry including patients with AS undergoing TAVI and surviving to hospital discharge.The primary endpoint was all-cause mortality or need for urgent readmission one year after TAVI.Results A total of 377 patients were included(mean age of 80.4 years).Most patients were independent or mildly dependent,with an optimal cognitive status.The proportion of frailty ranged from 17.6%to 49.8%.A total of 20 patients(5.3%)died and 110/377 patients(29.2%)died or were readmitted during follow up.Overall,most components of the geriatric assessment showed an association with clinical outcomes.Disability for instrumental activities showed a significant association with mortality and a strong association with the rate of mortality or readmission.The association between frailty and clinical outcomes was higher for short physical performance battery(SPPB),essential frailty toolset(EFT)and the frailty index based on comprehensive geriatric assessment(IF-VIG)and lower for Fried criteria and FRAIL scale.Conclusions AS patients from this series presented a good physical performance,optimal cognitive status and a reasonably low prevalence of frailty.The best predictive ability was observed for disability for instrumental activities and frailty as measured by the EFT,SPPB and the IF-VIG. 展开更多
关键词 transcatheter aortic valve implantation tavi analyze ability different tools Geriatric Assessment describe geriatric profile geriatric assessment tools Transcatheter Aortic Valve Implantation FRAILTY Aortic Stenosis
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Spatial Patterns and Controlling Factors of Soil Organic Carbon and Total Nitrogen in the Three River Headwaters Region,China 被引量:1
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作者 CUI Qiao LI Zongxing +2 位作者 FENG Qi ZHANG Baijuan ZHAO Yue 《Chinese Geographical Science》 2025年第1期131-148,共18页
The alpine ecosystem has great potential for carbon sequestration.Soil organic carbon(SOC)and total nitrogen(TN)are highly sensitive to climate change,and their dynamics are crucial to revealing the effect of climate ... The alpine ecosystem has great potential for carbon sequestration.Soil organic carbon(SOC)and total nitrogen(TN)are highly sensitive to climate change,and their dynamics are crucial to revealing the effect of climate change on the structure,function,and services of the ecosystem.However,the spatial distribution and controlling factors of SOC and TN across various soil layers and vegetation types within this unique ecosystem remain inadequately understood.In this study,256 soil samples in 89 sites were collected from the Three River Headwaters Region(TRHR)in China to investigate SOC and TN and to explore the primary factors affecting their distribution,including soil,vegetation,climate,and geography factors.The results show that SOC and TN contents in 0-20,20-40,40-60,and 60-80 cm soil layers are 24.40,18.03,14.04,12.40 g/kg and 2.46,1.90,1.51,1.17 g/kg,respectively;with higher concentrations observed in the southeastern region compared to the northwest of the TRHR.One-way analysis of variance reveals that SOC and TN levels are elevated in the alpine meadow and the alpine shrub relative to the alpine steppe in the 0-60 cm soil layers.The structural equation model explores that soil water content is the main controlling factor affecting the variation of SOC and TN.Moreover,the geography,climate,and vegetation factors notably indirectly affect SOC and TN through soil factors.Therefore,it can effectively improve soil water and nutrient conditions through vegetation restoration,soil improvement,and grazing management,and the change of SOC and TN can be fully understood by establishing monitoring networks to better protect soil carbon and nitrogen. 展开更多
关键词 controlling factors different soil layers soil organic carbon(SOC) soil total nitrogen(TN) alpine ecosystem the Three River Headwaters Region(TRHR) China
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问答
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《物理》 北大核心 2025年第8期594-594,共1页
Q:为什么无法从粒子物理出发推导出凝聚态物理?A:听过一个讲座,临结束时报告人问了一个问题:大家都知道“More is different”,那有人知道这篇文章还有一个副标题是什么吗?全场鸦雀无声。查阅后得知副标题是“Broken symmetry and the n... Q:为什么无法从粒子物理出发推导出凝聚态物理?A:听过一个讲座,临结束时报告人问了一个问题:大家都知道“More is different”,那有人知道这篇文章还有一个副标题是什么吗?全场鸦雀无声。查阅后得知副标题是“Broken symmetry and the nature of the hierarchical structure of science”,翻译过来就是“破缺的对称性与科学层级结构的本质”。 展开更多
关键词 凝聚态物理 粒子物理 问答 More is different
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美国《保健物理》(Health Physics)杂志英文摘要(2025年128卷第6期)
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《辐射防护》 北大核心 2025年第5期539-544,共6页
Evaluation of Gamma Index Analysis for Detecting Errors in Patient-specific Quality Assurance in Intensity Modulated Radiotherapy Taylan Tugrul1(1.Department of Radiation Oncology,Medicine Faculty of Van Yüzü... Evaluation of Gamma Index Analysis for Detecting Errors in Patient-specific Quality Assurance in Intensity Modulated Radiotherapy Taylan Tugrul1(1.Department of Radiation Oncology,Medicine Faculty of Van YüzüncüYıl University,Van,Turkey)Abstract:Quality assurance practices performed before treatment are believed to identify various potential errors.In this study,2-dimensional(2D)dosimetric results were analyzed by making some intentional mistakes in six different treatment plans.In this way,the detectability of errors was investigated.In all segments of all treatment plans,one of the multileaf collimators was kept fixed at different positions on the central axis.In addition to multileaf collimators error,gantry error was also examined in the study.The dose distribution results obtained by Treatment Planning System(TPS)were compared with those obtained by the 2D array device,both as local calculation and global calculation methods,using the gamma analysis method.When the results are examined in the case where the Multi-leaf collimators(MLC)is fixed at the 1 cm position. 展开更多
关键词 making some intentional mistakes six different treatment plansin multileaf collimators patient specific quality assurance gantry error intensity modulated radiotherapy assurance practices gamma index analysis
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Morphology-driven innovations in quantum dots: Unlocking enhanced photocatalytic potential
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作者 Hamid Ali Yasin Orooji +6 位作者 Basem Al Alwan Atef EL Jery Ahmed M.Abu-Dief Rawan AL-Faze Sheng-Rong Guo Bo Wu Asif Hayat 《Journal of Energy Chemistry》 2025年第12期790-846,I0018,共58页
Quantum dots(QDs) are semiconductor nanostructures that display unique optical and electronic properties due to quantum confinement effects at the nanoscale.Their efficiency in photocatalysis,particularly for energy-r... Quantum dots(QDs) are semiconductor nanostructures that display unique optical and electronic properties due to quantum confinement effects at the nanoscale.Their efficiency in photocatalysis,particularly for energy-related applications,is significantly influenced by their morphology,which can be precisely controlled using different synthesis parameters and techniques.For the first time,this review focuses on the important parameters that influence QDs morphology,such as precursor selection,reaction temperature and time,solvent effects,capping agents or ligands,doping and composition,postsynthesis treatments,and surfactants and stabilizers.It also discusses different synthesis approaches such as colloidal,solvothermal,hydrothermal,microwave-assisted,chemical vapor deposition(CVD),electrochemical,and biomimetic(green) methods,all offering different strategies for controlling QDs morphology.The review explores a range of QDs morphologies,including nanoflowers,nanowires,cubic,nanoribbons,nanofibers,porous,alloyed,nanotubes,heterostructures,core-shell,nanorods,nanosheets,hollow,nanospheres,and spherical particles,which directly influence band structures,surface states,light absorption,and charge carrier dynamics.These shape-dependent properties significantly govern the photocatalytic efficiency,charge separation,and reaction selectivity.Furthermore,we detail the unique contributions of different QDs families,including carbon QDs,metal oxide QDs,MXene-based QDs,perovskite QDs,and transition metal chalcogenide QDs,each offering distinct advantages in terms of stability,tunability,and light-harvesting efficiency.By correlating morphology with photocatalytic performance,this work emphasizes the strategic engineering of QDs morphology as a pathway to unlock superior performance in water splitting,hydrogen evolution reaction(HER),CO_(2) reduction,H_2O_(2) production,pollutant degradation,oxygen reduction process(ORR),and photocatalytic depolymerization.This work underscores the importance of tailoring QDs morphology to optimize their performance in photocatalysis,focusing on enhancing energy conversion and storage processes. 展开更多
关键词 Quantum dots(QDs) Different synthesis methods Different morphologies Photocatalytic applications
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Comprehensive Index Evaluation of the Cooling System with the Level Loop Thermosyphon System in Different Computing Hub Nodes in China
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作者 Li Ling Danhao Song +2 位作者 Qianlong Hu Zihao Xiang Zeyu Zhang 《Energy Engineering》 2025年第8期3309-3328,共20页
Rack-level loop thermosyphons have been widely adopted as a solution to data centers’growing energy demands.While numerous studies have highlighted the heat transfer performance and energy-saving benefits of this sys... Rack-level loop thermosyphons have been widely adopted as a solution to data centers’growing energy demands.While numerous studies have highlighted the heat transfer performance and energy-saving benefits of this system,its economic feasibility,water usage effectiveness(WUE),and carbon usage effectiveness(CUE)remain underexplored.This study introduces a comprehensive evaluation index designed to assess the applicability of the rack-level loop thermosyphon system across various computing hub nodes.The air wet bulb temperature Ta,w was identified as the most significant factor influencing the variability in the combination of PUE,CUE,and WUE values.The results indicate that the rack-level loop thermosyphon system achieves the highest score in Lanzhou(94.485)and the lowest in Beijing(89.261)based on the comprehensive evaluation index.The overall ranking of cities according to the comprehensive evaluation score is as follows:Gansu hub(Lanzhou)>Inner Mongolia hub(Hohhot)>Ningxia hub(Yinchuan)>Yangtze River Delta hub(Shanghai)>Chengdu Chongqing hub(Chongqing)>Guangdong-Hong Kong-Macao Greater Bay Area hub(Guangzhou)>Guizhou hub(Guiyang)>Beijing-Tianjin-Hebei hub(Beijing).Furthermore,Hohhot,Lanzhou,and Yinchuan consistently rank among the top three cities for comprehensive scores across all load rates,while Guiyang(at a 25%load rate),Guangzhou(at a 50%load rate),and Beijing(at 75%and 100%load rates)exhibited the lowest comprehensive scores. 展开更多
关键词 Data center rack level loop thermosyphon different Computing hub node different load rates comprehensive indicator analysis
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Update on the roles and applications of extracellular vesicles in depression
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作者 Jing Wu Jian Lu +5 位作者 Ming-Zhi Pan Xiao-Chu Gu Lu Dai Yun Wang Bin Shen Xiao-Bin Zhang 《World Journal of Psychiatry》 2025年第3期32-48,共17页
Depression is a prevalent mental disorder that affects numerous individuals,manifesting as persistent anhedonia,sadness,and hopelessness.Despite extensive research,the exact causes and optimal treatment approaches for... Depression is a prevalent mental disorder that affects numerous individuals,manifesting as persistent anhedonia,sadness,and hopelessness.Despite extensive research,the exact causes and optimal treatment approaches for depression remain unclear.Extracellular vesicles(EVs),which carry biological molecules such as proteins,lipids,nucleic acids,and metabolites,have emerged as crucial players in both pathological and physiological processes.EVs derived from various sources exert distinct effects on depression.Specifically,EVs released by neurons,astrocytes,microglia,oligodendrocytes,immune cells,stem cells,and even bacteria contribute to the pathogenesis of depression.Moreover,there is growing interest in potential of EVs as diagnostic and therapeutic tools for depression.This review provides a comprehensive overview of recent research on EVs from different sources,their roles in depression,and their potential clinical applications. 展开更多
关键词 DEPRESSION Extracellular vesicles EXOSOMES Biomarkers Different sources
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Upgraded Partnership
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作者 ZHANG HUI 《China Today》 2025年第11期46-49,共4页
MADRID and Beijing,though thousands of miles apart,have become a model for mutual learning between different civilizations through mutual respect and dialogue.In November,Spanish King Felipe VI will visit China.This w... MADRID and Beijing,though thousands of miles apart,have become a model for mutual learning between different civilizations through mutual respect and dialogue.In November,Spanish King Felipe VI will visit China.This will be another milestone in bilateral relations following the 2007 visit of former Spanish King Juan Carlos I to China and President Xi Jinping’s visit to Spain in 2018. 展开更多
关键词 mutual learning bilateral relations DIALOGUE state visit different civilizations mutual respect
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Different Greening Schemes for Numerical Simulation Research on Summer Thermal Environment in Guangzhou Campus
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作者 LI Hai-yan LI Jiang-bo +3 位作者 WU Xiao-xuan PAN Wei-juan CAI Ming-fu SUN Jia-ren 《Journal of Tropical Meteorology》 2025年第4期406-421,共16页
Reasonable greening design can effectively alleviate campus heat environment issues.This study uses the ENVI-met numerical model,along with in-situ observations and simulations,to analyze the thermal environment under... Reasonable greening design can effectively alleviate campus heat environment issues.This study uses the ENVI-met numerical model,along with in-situ observations and simulations,to analyze the thermal environment under three different greening schemes in typical areas of the Guangzhou University campus.The results indicate that the outdoor thermal environment is significantly influenced by the underlying surface materials and vegetation.The temperature of brick-paved surface is 0.9℃higher than that of natural soil surfaces under tree shade.Numerical simulations further confirm that increasing vegetation coverage effectively reduces outdoor air temperature.When the greening rate increases to 40%,the outdoor average temperature decreases by 0.7℃and relative humidity increases by approximately 4%,while wind speed remains minimal change.The cooling effect of vegetation is found to extend vertically to an altitude of 13 m.As the greening rate increases from 15%to 40%,the Mean Radiant Temperature(MRT)decreases from 50.6℃to 28.9℃,which is lower than the average ambient temperature,indicating improved thermal conditions.The Physiological Equivalent Temperature(PET)decreases from 40.2℃to 30.0℃,with the proportion of the areas classified as″very hot″reducing by 36.8%,significantly improving thermal comfort across most areas.Therefore,changing the ground material and greening landscape design can effectively alter the outdoor wind and thermal environment of the campus,thereby enhancing the thermal comfort for the campus community. 展开更多
关键词 MICROCLIMATE thermal environment ENVI-met different greening schemes
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A comprehensive review:MOFs and their derivatives as high-performance supercapacitor electrodes
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作者 Malaika Arshad Zia Ul Haq Khan +7 位作者 Swera Talib Sana Sabahat Noor Samad Shah Huma Ajab Farooq Ahmad Syed Khasim M.A.Diab Heba A.El-Sabban 《Chinese Journal of Structural Chemistry》 2025年第9期77-109,共33页
An expanding human population and technological progress demand clean and effective energy-storing systems.Within the realm of energy-storing devices,supercapacitors(SCs)have grabbed huge focus owing to their high-pow... An expanding human population and technological progress demand clean and effective energy-storing systems.Within the realm of energy-storing devices,supercapacitors(SCs)have grabbed huge focus owing to their high-power density,unique cycling stability,and fast charging discharging capabilities.Electrode material has a prominent impact on the effectiveness of SCs.Several types of electrode materials have been used,encompassing varied metal oxides,activated carbon,conducting polymers,and MOFs.Metal organic frameworks(MOFs)are considered emerging electrode candidates,which could be ascribed to the tunable porosity,large surface areas,and designed morphology.This review shows a detailed analysis of various mono-,bi-,and tri-metallic MOFs along with derivatives in SC applications,their structural characteristics,and synthetic strategies.It also critically evaluates MOFs potential to boost the SC's energy density,power density,stability,and conductivity.Also,it underscores their significance in the establishment of future-oriented energy storage applications. 展开更多
关键词 MOFS Energy storage Different metallic MOF SUPERCAPACITOR
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Hierarchical zeolites stabilized cobalt(II)as propane dehydrogenation catalyst:Enhanced activity and coke tolerance via alkaline post-treatment
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作者 Kun Yang Anhui Li +7 位作者 Peng Zhang Guilin Liu Liusai Huang Yumeng Fo Luyuan Yang Xiangyang Ji Jian Liu Weiyu Song 《Chinese Chemical Letters》 2025年第5期348-353,共6页
Transition metal cobalt exhibits strong activation capabilities for alkanes,however,the instability of Co sites leads to sintering and coke deposition,resulting in rapid deactivation.Hierarchical zeolites,with their d... Transition metal cobalt exhibits strong activation capabilities for alkanes,however,the instability of Co sites leads to sintering and coke deposition,resulting in rapid deactivation.Hierarchical zeolites,with their diverse pore structures and high surface areas,are used to effectively anchor metals and enhance coke tolerance.Herein,a post-treatment method using an alkaline solution was employed to synthesize meso-microporous zeolite supports,which were subsequently loaded with Co species for propane dehydrogenation catalyst.The results indicate that the application of NaOH,an inorganic base,produces supports with a larger mesopore volume and more abundant hydroxyl nests compared to TPAOH,an organic base.UV-vis,Raman,and XPS analyses reveal that Co in the 0.5Co/SN-1-0.05 catalyst is mainly in the form of tetrahedral Co^(2+),which effectively activates C-H bonds.In contrast,the 0.5Co/S-1 catalyst contains mainly Co_(3)O_(4)species.Co^(2+)supported on hierarchical zeolites shows better propane conversion(58.6%)and propylene selectivity(>96%)compared to pure silica zeolites.Coke characterization indicates that hierarchical zeolites accumulate more coke,but it is mostly in the form of easily removable disordered carbon.The mesopores in the microporous zeolite support help disperse the active Co metal and facilitate coke removal during dehydrogenation,effectively preventing deactivation from sintering and coke coverage. 展开更多
关键词 Propane dehydrogenation Hierarchical zeolites Different alkaline treatment Cobalt catalyst Coke tolerance
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Wind-sand flow response law of concave surface upwind plane curve embankment under different wind directions
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作者 LI Liangying JI Shuai +2 位作者 XIN Guowei WANG Xu LI Qi 《Journal of Mountain Science》 2025年第12期4379-4391,共13页
Understanding the characteristics of windsand flow field in the curve section of desert highway under different wind directions is helpful for reducing the wind-sand damage in the curve section.Therefore,taking the de... Understanding the characteristics of windsand flow field in the curve section of desert highway under different wind directions is helpful for reducing the wind-sand damage in the curve section.Therefore,taking the desert section of Wuma Expressway in Zhongwei city,Ningxia,China as the research background,the wind-sand flow field and sand accumulation phenomenon of concave surface plane curve embankment under different wind directions is calculated and analyzed by computational fluid dynamics(CFD)numerical simulation method.The results show that:(1)Under different wind directions,along the direction of the route,at the starting point of the route,the windward slope of the embankment is a circular arc section,which reduces the resistance of wind-sand flow and promotes the acceleration of sand particles.In the middle of the route,the low-speed area of the windward slope toe and the leeward slope toe is small;at the end of the route,the high-speed area on the shoulder side of the leeward road rises upward.(2)Under different wind directions,the smaller the angle between the wind direction and the route,the stronger the lateral transport effect on the wind-blown sand flow,and the more sand particles transported along the route direction.(3)Under different wind directions,in the concave windward horizontal curve,with the increase of the angle,the sand area on the top of the embankment shows an increasing trend.Whenα=30°,45°,60°,75°,the percentage of the sand area on the top of the embankment to the total embankment area is 0%,33.3%,64.4%,71.0%,respectively.(4)Under different wind directions,along the route direction,the sand transport efficiency of the concave surface upwind plane curve embankment shows a decreasing trend.In the case of a certain radius of the horizontal curve,the angle range between the wind direction and the concave horizontal curve route is recommended to be 30°-45°. 展开更多
关键词 Desert highway Wind-sand flow Flat curve Numerical simulation Different wind directions
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Vertical variations of ozone transport flux at multiple altitudes and identification of major transport direction in the North China Plain
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作者 Hanyu Zhang Longyue Lv +5 位作者 Zhiliang Yao Wantong Guo Xuejun Wang Wenxing Shan Xin Li Xianbao Shen 《Journal of Environmental Sciences》 2025年第9期488-500,共13页
The North China Plain(NCP)frequently experiences ozone pollution events,which are generally related to cross-border transport at multiple scales.However,current methods of calculating ozone transport are insufficient ... The North China Plain(NCP)frequently experiences ozone pollution events,which are generally related to cross-border transport at multiple scales.However,current methods of calculating ozone transport are insufficient to account for ozone transport at different altitudes.To further understand the characteristics of ozone transport,we applied theWeather Research and Forecasting(WRF)model and the Comprehensive Air Quality Model with Extensions(CAMx)based on flux calculation method.The results showed that the simulated flux calculation method was suitable for revealing the evolutionary trend of ozone fluxes.Monthly inflows,outflows,and total net fluxes ranged from-32985.45 to 37361.46 t/d and indicated strong transport and significant spatial and temporal variations of ozone in the urban boundary segments.Vertical distribution analysis of the net ozone fluxes demonstrated that the net fluxes varied with the altitude,and the altitude at which the corresponding peaks were located had a strong correlation with the neighborhood and season.It was noteworthy that there were three main transport directions throughout the year,namely northwest-southeast(NW-SE),southeast-northwest(SE-NW),and southwestnortheast(SW-NE).Additionally,the ozone flux was mainly affected by temperature,wind speed,and ozone concentration,with the correlation coefficient varying by season and altitude,up to 0.78.Moreover,the correlation analysis of ozone flux and wind direction in each city further verified the accuracy of the transport direction.This paper can provide scientific and technological support for the study of ozone generation mechanisms and the solution of urban/interregional ozone pollution problems. 展开更多
关键词 WRF-CAMx model Ozone flux Different altitudes Transport directions Correlation analysis
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Evaluation of Rivaroxaban at Different Doses on Symptoms,Blood Indicators,and Safety in Patients with Pulmonary Embolism during the Maintenance Phase
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作者 Xing Cheng 《Science International Innovative Medicine》 2025年第3期5-11,共7页
Objective:To investigate the differential effects of different rivaroxaban dosing regimens on symptom relief,fluctuations in laboratory parameters,and medication safety in patients with stable pulmonary embolism(PE).M... Objective:To investigate the differential effects of different rivaroxaban dosing regimens on symptom relief,fluctuations in laboratory parameters,and medication safety in patients with stable pulmonary embolism(PE).Methods:This study enrolled 100 patients in the maintenance phase of PE who were treated at our hospital between January 2022 and December 2023.They were randomly divided into a control group and an observation group using a random number table,with 50 subjects in each group.The treatment period was uniformly set at 6 months.The control group received oral rivaroxaban 10 mg once daily,while the observation group received oral rivaroxaban 5 mg once daily.The study focused on comparing the two groups regarding the degree of clinical symptom relief,coagulation function parameters(including D-dimer levels,PT,and APTT),cardiac function markers(NT-proBNP),and drug-related adverse events.All data were processed using SPSS 26.0 statistical software.Measurement data are presented as mean±standard deviation,intergroup differences were verified by t-test,categorical variables were analyzed by chi-square test,and the statistical significance level was set at P<0.05.Results:After six months of treatment intervention,there was no significant difference in the overall relief of core clinical symptoms such as dyspnea and chest pain between the two groups.Regarding laboratory indicators,post-treatment D-dimer levels,prothrombin time,activated partial thromboplastin time,and NT-proBNP values were significantly optimized compared to baseline in both groups(P<0.05),but intergroup comparisons did not reach statistical significance.Notably,the overall incidence of bleeding events in the observation group was significantly lower than that in the control group(P<0.05),while there were no significant differences in the incidence rates of other adverse events between the two groups.Conclusion:In the maintenance phase treatment of pulmonary embolism,rivaroxaban 5 mg and 10 mg doses are equivalent in efficacy regarding improvement of clinical symptoms and blood indicators.However,the 5 mg dose significantly reduces the risk of bleeding,offers better safety,and is more suitable for long-term anticoagulation management in some high-risk populations. 展开更多
关键词 RIVAROXABAN Different Doses Pulmonary Embolism Maintenance Phase Treatment Clinical Symptoms Blood Indicators SAFETY Anticoagulation Therapy
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