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Design Guidelines for Composition of Brazing Filler Metals and Evolution Mechanisms of Typical Microstructures 被引量:4
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作者 Long Weimin 《稀有金属材料与工程》 北大核心 2025年第4期837-853,共17页
Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler ... Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects. 展开更多
关键词 design of brazing filler metals design guidelines for composition Ag based brazing filler metals eutectic structures evolution
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Quantitative Analysis of the Fatty Acid Compositions of Different Oils and Associations with Antioxidant Capacity and Oxidative Stability 被引量:1
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作者 LIU Junchen SUN Xiaoman +3 位作者 ZHANG Huirong SHAO Haofan LING Xiao LI Li 《现代食品科技》 北大核心 2025年第4期305-315,共11页
Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships w... Fatty acids are the main constituents of vegetable oils.To determine the fatty acid compositions of small trade vegetable oils and some less well studied beneficial vegetable oils,and investigate their relationships with antioxidant activity and oxidative stability,gas chromatography-mass spectrometry was performed to characterize the associated fatty acid profiles.The antioxidant activity of vegetable oils,based on their DPPH-scavenging capacity(expressed as IC_(50) values),was used to assess their impact on human health,and their oxidative stability was characterized by performing lipid oxidation analysis to determine the oxidative induction time of fats and oils.In addition,correlation analyses were performed to examine associations between the fatty acid composition of the oils and DPPH-scavenging capacity and oxidative stability.The results revealed that among the assessed oils,coffee seed oil has the highest saturated fatty acid content(355.10 mg/g),whereas Garddenia jaminoides oil has the highest unsaturated fatty acid content(844.84 mg/g).Coffee seed oil was also found have the lowest DPPH IC_(50) value(2.30 mg/mL)and the longest oxidation induction time(17.09 h).Correlation analysis revealed a significant linear relationship(P<0.05)between oxidative stability and unsaturated fatty acid content,with lower contents tending to be associated with better oxidative stability.The findings of this study provide reference data for the screening of functional edible vegetable oils. 展开更多
关键词 gas chromatography-mass spectrometry vegetable oil fatty acid composition oxidative stability antioxidant capacity
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Research progress of structural regulation and composition optimization to strengthen absorbing mechanism in emerging composites for efficient electromagnetic protection 被引量:4
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作者 Pengfei Yin Di Lan +7 位作者 Changfang Lu Zirui Jia Ailing Feng Panbo Liu Xuetao Shi Hua Guo Guanglei Wu Jian Wang 《Journal of Materials Science & Technology》 2025年第1期204-223,共20页
With the increasing complexity of the current electromagnetic environment,excessive microwave radi-ation not only does harm to human health but also forms various electromagnetic interference to so-phisticated electro... With the increasing complexity of the current electromagnetic environment,excessive microwave radi-ation not only does harm to human health but also forms various electromagnetic interference to so-phisticated electronic instruments.Therefore,the design and preparation of electromagnetic absorbing composites represent an efficient approach to mitigate the current hazards of electromagnetic radiation.However,traditional electromagnetic absorbers are difficult to satisfy the demands of actual utilization in the face of new challenges,and emerging absorbents have garnered increasing attention due to their structure and performance-based advantages.In this review,several emerging composites of Mxene-based,biochar-based,chiral,and heat-resisting are discussed in detail,including their synthetic strategy,structural superiority and regulation method,and final optimization of electromagnetic absorption ca-pacity.These insights provide a comprehensive reference for the future development of new-generation electromagnetic-wave absorption composites.Moreover,the potential development directions of these emerging absorbers have been proposed as well. 展开更多
关键词 Microwave absorption Structural regulation Performance optimization Emerging composites Synthetic strategy
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High-resolution Simulation Dataset of Hourly PM_(2.5)Chemical Composition in China(CAQRA-aerosol)from 2013 to 2020 被引量:1
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作者 Lei KONG Xiao TANG +14 位作者 Jiang ZHU Zifa WANG Bing LIU Yuanyuan ZHU Lili ZHU Duohong CHEN Ke HU Huangjian WU Qian WU Jin SHEN Yele SUN Zirui LIU Jinyuan XIN Dongsheng JI Mei ZHENG 《Advances in Atmospheric Sciences》 2025年第4期697-712,共16页
Scientific knowledge on the chemical compositions of fine particulate matter(PM_(2.5)) is essential for properly assessing its health and climate effects,and for decisionmakers to develop efficient mitigation strategi... Scientific knowledge on the chemical compositions of fine particulate matter(PM_(2.5)) is essential for properly assessing its health and climate effects,and for decisionmakers to develop efficient mitigation strategies.A high-resolution PM_(2.5) chemical composition dataset(CAQRA-aerosol)is developed in this study,which provides hourly maps of organic carbon,black carbon,ammonium,nitrate,and sulfate in China from 2013 to 2020 with a horizontal resolution of 15 km.This paper describes the method,access,and validation results of this dataset.It shows that CAQRA-aerosol has good consistency with observations and achieves higher or comparable accuracy with previous PM_(2.5) composition datasets.Based on CAQRA-aerosol,spatiotemporal changes of different PM_(2.5) compositions were investigated from a national viewpoint,which emphasizes different changes of nitrate from other compositions.The estimated annual rate of population-weighted concentrations of nitrate is 0.23μg m^(−3)yr^(−1) from 2015 to 2020,compared with−0.19 to−1.1μg m^(−3)yr^(−1) for other compositions.The whole dataset is freely available from the China Air Pollution Data Center(https://doi.org/10.12423/capdb_PKU.2023.DA). 展开更多
关键词 PM_(2.5)composition dataset black carbon organic carbon AMMONIUM NITRATE SULFATE
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Effect of preprocessing on performances of machine learning-based mineral composition analysis on gas hydrate sediments,Ulleung Basin,East Sea 被引量:1
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作者 Hongkeun Jin Ju Young Park +3 位作者 Sun Young Park Byeong-Kook Son Baehyun Min Kyungbook Lee 《Petroleum Science》 2025年第1期151-162,共12页
Gas hydrate(GH)is an unconventional resource estimated at 1000-120,000 trillion m^(3)worldwide.Research on GH is ongoing to determine its geological and flow characteristics for commercial produc-tion.After two large-... Gas hydrate(GH)is an unconventional resource estimated at 1000-120,000 trillion m^(3)worldwide.Research on GH is ongoing to determine its geological and flow characteristics for commercial produc-tion.After two large-scale drilling expeditions to study the GH-bearing zone in the Ulleung Basin,the mineral composition of 488 sediment samples was analyzed using X-ray diffraction(XRD).Because the analysis is costly and dependent on experts,a machine learning model was developed to predict the mineral composition using XRD intensity profiles as input data.However,the model’s performance was limited because of improper preprocessing of the intensity profile.Because preprocessing was applied to each feature,the intensity trend was not preserved even though this factor is the most important when analyzing mineral composition.In this study,the profile was preprocessed for each sample using min-max scaling because relative intensity is critical for mineral analysis.For 49 test data among the 488 data,the convolutional neural network(CNN)model improved the average absolute error and coefficient of determination by 41%and 46%,respectively,than those of CNN model with feature-based pre-processing.This study confirms that combining preprocessing for each sample with CNN is the most efficient approach for analyzing XRD data.The developed model can be used for the compositional analysis of sediment samples from the Ulleung Basin and the Korea Plateau.In addition,the overall procedure can be applied to any XRD data of sediments worldwide. 展开更多
关键词 Sample-based preprocessing X-ray diffraction(XRD) Machine learning Mineral composition Gas hydrate(GH) Ulleung basin
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Products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball
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作者 ZHANG Chao QIN Yuehai 《中山大学学报(自然科学版)(中英文)》 北大核心 2025年第2期160-169,共10页
The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic fu... The boundness and compactness of products of multiplication,composition and differentiation on weighted Bergman spaces in the unit ball are studied.We define the differentiation operator on the space of holomorphic functions in the unit ball by radial derivative.Then we extend the Sharma's results. 展开更多
关键词 composition operator multiplication operator differentiation operator weighted Bergman space
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Effect of Nitrocellulose-modified HTPB Binder on the Thermal Decomposition Behavior of Ammonium Nitrate/Magnesium Solid Propellant
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作者 Mohammed Jouini Amir Abdelaziz +4 位作者 Ahmed Fouzi Tarchoun Fateh Chalghoum Yash Pal Weiqiang Pang Djalal Trache 《火炸药学报》 北大核心 2025年第4期372-381,I0004,共11页
An energetic binder based on hydroxyl-terminated polybutadiene(HTPB),doped with different ratios of nitrocellulose(NC)(10%,20%,30%,and 50%),was developed to study the effect of NC doping on the thermal decomposition b... An energetic binder based on hydroxyl-terminated polybutadiene(HTPB),doped with different ratios of nitrocellulose(NC)(10%,20%,30%,and 50%),was developed to study the effect of NC doping on the thermal decomposition behavior of a composite propellant(CP)comprising ammonium nitrate(AN)as an oxidizer and magnesium(Mg)as a fuel.Optimization of the propellant formulation was conducted using Chemical Equilibrium with Applications-National Aeronautics and Space Administration(CEA-NASA)software,which demonstrated an increase in specific impulse by 12.09 s when the binder contained 50%NC.Fourier-transform infrared spectroscopy(FTIR)analysis confirmed the excellent compatibility between the components,and density measurements revealed an increase of 6.4%with a higher NC content.Morphological analysis using optical microscopy showed that NC doping improved the uniformity and compactness of the surface,reduced cavities,and achieved a more homogeneous particle distribution.Differential scanning calorimetry(DSC)analysis indicated a decrease in the decomposition temperature of the propellant as the NC content increased,while kinetic studies revealed a 48.68%reduction in the activation energy when 50%NC was incorporated into the binder.These findings suggest that the addition of NC enhances combustion efficiency and improves overall propellant performance.This study highlights the potential of the new HTPB-NC energetic binder as a promising approach for advancing solid propellant technology. 展开更多
关键词 physical chemistry composite propellant HTPB NITROCELLULOSE energetic binder thermal behavior
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Homogenization-based numerical framework of second-phase reinforced alloys integrating strain gradient effects
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作者 Haidong LIN Yiqi MAO Shujuan HOU 《Applied Mathematics and Mechanics(English Edition)》 2025年第7期1273-1294,共22页
The acuurate prediction of the time-dependent mechanical behavior and deformation mechanisms of second-phase reinforced alloys under size effects is critical for the development of high-strength ductile metals and all... The acuurate prediction of the time-dependent mechanical behavior and deformation mechanisms of second-phase reinforced alloys under size effects is critical for the development of high-strength ductile metals and alloys for dynamic applications.However,solving their responses using high-fidelity numerical methods is computationally expensive and,in many cases,impractical.To address this issue,a dual-scale incremental variational formulation is proposed that incorporates the influence of plastic gradients on plastic evolution characteristics,integrating a strain-rate-dependent strain gradient plasticity model and including plastic gradients in the inelastic dissipation potential.Subsequently,two minimization problems based on the energy dissipation mechanisms of strain gradient plasticity,corresponding to the macroscopic and microscopic structures,are solved,leading to the development of a homogenization-based dual-scale solution algorithm.Finally,the effectiveness of the variational model and tangent algorithm is validated through a series of numerical simulations.The contributions of this work are as follows:first,it advances the theory of self-consistent computational homogenization modeling based on the energy dissipation mechanisms of plastic strain rates and their gradients,along with the development of a rigorous multi-level finite element method(FE2)solution procedure;second,the proposed algorithm provides an efficient and accurate method for evaluating the time-dependent mechanical behavior of second-phase reinforced alloys under strain gradient effects,exploring how these effects vary with the strain rate,and investigating their potential interactions. 展开更多
关键词 computational homogenization strain gradient effect strain rate inelastic dissipation second-phase reinforced alloy
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2-complex Symmetric Weighted Composition Operators on Fock Space of C^(N)
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作者 JIANG Zhijie 《数学进展》 北大核心 2025年第1期37-49,共13页
The aim of the present paper is to study 2-complex symmetric bounded weighted composition operators on the Fock space of C^(N) with the conjugations J and J_(t,A,b) defined by ■ respectively,where k(z_(1),...,z_N)=(... The aim of the present paper is to study 2-complex symmetric bounded weighted composition operators on the Fock space of C^(N) with the conjugations J and J_(t,A,b) defined by ■ respectively,where k(z_(1),...,z_N)=(■,...,■),t∈C,b∈C^(N) and A is a linear operator on C^(N).An example of 2-complex symmetric bounded weighted composition operator with the conjugation J_(t,A,b) is given. 展开更多
关键词 Fock space weighted composition operator 2-complex symmetric operator reproducing kernel function
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Effects of composition ratio of TiCu precursor on dealloying behavior in molten Mg and microstructural characteristics of Mg-Ti composites
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作者 Jee Eun Jang Bo Hyun Park +1 位作者 Soo-Hyun Joo Sung Hyuk Park 《Journal of Magnesium and Alloys》 2025年第6期2784-2799,共16页
Metal composites produced through the liquid metal dealloying(LMD)process feature an advanced matrix-matrix composite structure,where two metallic materials form a continuous,three-dimensional interconnected network.T... Metal composites produced through the liquid metal dealloying(LMD)process feature an advanced matrix-matrix composite structure,where two metallic materials form a continuous,three-dimensional interconnected network.This study investigates the effects of Ti Cu precursor compositions on dealloying behavior and microstructural evolution in liquid Mg,using Ti_(50)Cu_(50)and Ti_(30)Cu_(70)precursors.The initial microstructure of the precursor significantly influences dealloying kinetics and phase transitions.The single-phase Ti_(50)Cu_(50)precursor exhibits a faster initial dealloying rate due to its homogeneous structure,yet complete dealloying requires 90 min.In contrast,the dualphase Ti_(30)Cu_(70)precursor achieves complete dealloying in 30 min,demonstrating the impact of a higher Cu concentration on accelerating the process kinetics.Additionally,the study explores the coarsening behavior and hardness variations during the LMD process,along with the microstructural characteristics of Mg-Ti composites fabricated from these two precursors.The findings highlight the critical role of precursor composition in tailoring the microstructure and properties of Mg-Ti composites produced through the LMD process,demonstrating its potential for advanced composite material manufacturing. 展开更多
关键词 Liquid metal dealloying Precursor composition Mg-Ti composite 3D interconnected structure HARDNESS
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Composition Analysis of Lycophytes and Ferns in Yunzhongshan Nature Reserve, Fujian Province
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作者 Jinquan SHEN Minyong LU +4 位作者 Baohua WU Lingming LIN Jinhuo HE Ying FENG Yinbing XIE 《Plant Diseases and Pests》 2025年第2期34-37,共4页
[Objectives]To analyze the composition of lycophytes and ferns in Yunzhongshan Nature Reserve,Fujian Province.[Methods]This study examined the composition of lycophytes and ferns in Yunzhongshan Nature Reserve through... [Objectives]To analyze the composition of lycophytes and ferns in Yunzhongshan Nature Reserve,Fujian Province.[Methods]This study examined the composition of lycophytes and ferns in Yunzhongshan Nature Reserve through field investigations and specimen identification,supplemented by a review of relevant literature.[Results]A total of 84 species of lycophytes and ferns were identified,encompassing 55 genera and 29 families.This included 14 species of lycophytes distributed across 8 genera and 3 families,as well as 70 species of ferns belonging to 47 genera and 26 families.Polypodiaceae and Selaginella were the dominant family and genus,respectively,while oligospecific families and monotypic genera were significant components of lycophytes and ferns in the region.The distribution types of these families were primarily cosmopolitan and tropical.The Germline differentiation degree(SD)was 3.34,and the proportion of rare or endangered species among lycophytes and ferns was 8.33%.[Conclusions]Yunzhongshan Nature Reserve possesses a diverse array of lycophyte and fern species.This study offers valuable scientific insights that can inform efforts related to the conservation of biodiversity,resource utilization and development,species introduction,and system evolution of lycophytes and ferns within the reserve. 展开更多
关键词 NATURE RESERVE LYCOPHYTES FERNS composition
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Determination of the kidney stone composition using infrared spectroscopy in Iran at a national referral center during 2019-2023
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作者 Abbas Basiri Azin Tahvildari +2 位作者 Mohammad Naji Pardis Ziaeefar Amir H.Kashi 《Asian Journal of Urology》 2025年第1期72-78,共7页
Objective The national lifetime prevalence of urolithiasis is estimated at 6.6%in Iran.However,reports on the composition of kidney stones have been based on imprecise methods like the chemical analysis.No prior large... Objective The national lifetime prevalence of urolithiasis is estimated at 6.6%in Iran.However,reports on the composition of kidney stones have been based on imprecise methods like the chemical analysis.No prior large-scale study has reported the composition of kidney stones based on the gold-standard methods(X-ray diffraction or infrared spectroscopy)in Iran.This study aimed to provide the composition of kidney stones based on Fourier transform infrared spectroscopy.Methods This is a cross-sectional study assessing urinary stone composition from various cities in Iran at a referral center using infrared spectroscopy from February 2019 to March 2023.Results This study determined the stone composition of 1092 patients from 10 cities in Iran.Overall,the majority of stones were composed of calcium oxalate(n=498;45.6%)and uric acid(UA,n=488;44.7%)followed by cystine(n=49;4.5%)and struvite(n=28;2.6%).Stone composition in Shiraz and Isfahan was roughly similar with a higher percentage of UA stones(53.4%and 53.6%,respectively)while the capital city of Iran(Tehran)had less frequent UA stones(39.9%)with a higher percentage of calcium oxalate stones.The percentage of UA stones increased with age as it was 11.1%in children,42.7%in adults,and 83.3%in geriatric patients(p<0.001).About 29.6%of cystine stones were observed in children.Conclusion The most frequent stone composition among kidney stones in Iran was calcium oxalate and UA stones.This relative frequency of UA stones is considerably higher than many international reports from neighboring as well as distant countries.More cystine stones were observed in children and women.Geriatric patients’stones were mostly composed of UA. 展开更多
关键词 Kidney stone UROLITHIASIS Infrared spectroscopy Stone composition
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Both composition and configuration of forests and urban development shape bat activity and diversity in North American temperate forests
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作者 Sihao Chen Han Li 《Forest Ecosystems》 2025年第5期974-986,共13页
Temperate forest ecosystems are important habitats for many bat species. However, these habitats are increasingly affected by anthropogenic disturbances, particularly urban development, leading to landscapes with vary... Temperate forest ecosystems are important habitats for many bat species. However, these habitats are increasingly affected by anthropogenic disturbances, particularly urban development, leading to landscapes with varying land cover composition and configuration. Limited research has examined how forest and urban landscape composition and configuration influence bat activity and diversity. Using a multi-year statewide bat acoustic monitoring dataset from North Carolina, USA, we investigated the effects of forest and urban composition and configuration at multiple spatial scales on bat activity and diversity. First, we constructed single-variable landscape index regression models and found that both the composition and configuration of forests and urban developments influenced bat activity and diversity in a species-specific manner. Next, we applied a hierarchical partitioning approach to compare the relative contributions of composition and configuration indices in explaining variance in bat activity. For big brown bats and hoary bats, evergreen forest and urban development composition indices contributed the most to explaining activity variance. In contrast, for eastern red bats, evening bats, and tricolored bats, deciduous forest fragmentation indices describing landscape configuration were the most influential factors. Silver-haired bat activity variance was primarily explained by an evergreen forest fragmentation index. Lastly, urban development configuration indices were the strongest predictors of Mexican free-tailed bat activity and total bat activity. These results suggest that forest and urban landscape configuration should be considered in conservation and management planning for North American temperate forest ecosystems, particularly in regions that have not experienced drastic deforestation in recent decades. 展开更多
关键词 Bats CHIROPTERA composition Confguration FORESTS Landscape index Urban
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Arsenic mobility and microbial community composition in the sediments of coastal wetlands driven by tidal action
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作者 Ting Luo Wei Qin +4 位作者 Yuzhong Wang Yan Sun Sheng Kong Yang Zou Weihao Liang 《Journal of Environmental Sciences》 2025年第7期99-108,共10页
Arsenic(As)pollution in coastal wetlands has been receiving growing attention.However,the exact mechanism of As mobility driven by tidal action is still not completely understood.The results reveal that lower total As... Arsenic(As)pollution in coastal wetlands has been receiving growing attention.However,the exact mechanism of As mobility driven by tidal action is still not completely understood.The results reveal that lower total As concentrations in solution were observed in the flood-ebb treatment(FE),with the highest concentration being 7.1μg/L,and As(V)was the predominant species.However,elevated levels of total As in solution were found in the flooded treatment(FL),with a maximum value of 14.5μg/L after 30 days,and As(III)was the predominant form.The results of dissolved organicmatter(DOM)suggest that in the early to mid-stages of the incubation,fulvic acid-like substances might be utilized by microorganisms as electron donors or shuttle bodies,facilitating the reductive release of As/Fe from sediments.Both flood-ebb and flooded treatments promoted the transformation of crystalline iron hydrous oxides-bound As into residual forms.However,prolonged flooded conditions more readily facilitated the formation of specific adsorption forms of As and the reduction of crystalline iron hydrous oxides-bound As,increasing As mobility.In addition,the flood-ebb tides have been found to increase the diversity ofmicrobial populations.The main microbial genera in the flood-ebb treatment included Salinimicrobium,Erythrobacter,Yangia,Sulfitobacter,and Marinobacter.Bacillus,Psychrobacter,and Yangia showed a significant correlation with As(V).In flooded treatment,Bacillus,Pseudomonas,and Geothermobacter played a major role in the reduction and release of As.This study significantly contributes to the current understanding of how As behaves in diverse natural environments. 展开更多
关键词 ARSENIC MOBILITY Coastal wetlands Tidal action Microbial composition
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Composition design of fullerene-based hybrid electron transport layer for efficient and stable wide-bandgap perovskite solar cells
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作者 Shuai Zeng Hui Wang +11 位作者 Xiangyang Li Hailin Guo Linfeng Dong Chuanhang Guo Zhenghong Chen Jinpeng Zhou Yuandong Sun Wei Sun Liyan Yang Wei Li Dan Liu Tao Wang 《Journal of Energy Chemistry》 2025年第3期172-178,共7页
Fullerene derivatives[6,6]-phenyl-C61-butyric acid methyl ester(PC_(61)BM)has been routinely used as the electron transport layer(ETL)in perovskite solar cells due to its suitable energy levels and good solution proce... Fullerene derivatives[6,6]-phenyl-C61-butyric acid methyl ester(PC_(61)BM)has been routinely used as the electron transport layer(ETL)in perovskite solar cells due to its suitable energy levels and good solution processability.However,its electron mobility and conductivity still need to be further enhanced for constructing high performance perovskite solar cells(PSCs).Herein,by doping the PC_(61)BM with a p-type polymer PM6 and n-type molecule ITIC,efficient wide-bandgap perovskite solar cells with improved efficiency and operational/storage stability are obtained.Further spectroscopy and electric measurements indicate PM6 and ITIC can both passivate defects at the perovskite/ETL interface,meanwhile ITIC can elevate the Fermi level of PC_(61)BM to enhance conductivity and PM6 can improve the photo-induced electron mobility of the ETL,facilitating charge extraction and reducing charge recombination.As the results,Cs_(0.17)FA_(0.83)Pb(I_(0.83)Br_(0.17))_(3)wide-bandgap PSCs with PM6:PC_(61)BM:ITIC as the ETL demonstrates a superior efficiency of 22.95%,compared to 20.89%of the PC_(61)BM assisted device. 展开更多
关键词 Perovskite solar cells FULLERENE Electron transport layer composition
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Advances in Crack Formation Mechanisms,Evaluation Models,and Compositional Strategies for Additively Manufactured Nickel-Based Superalloys
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作者 Huabo Wu Jialiao Zhou +4 位作者 Lan Huang Zi Wang Liming Tan Jin Lv Feng Liu 《Computer Modeling in Engineering & Sciences》 2025年第6期2675-2709,共35页
Nickel-based superalloys are indispensable for high-temperature engineering applications,yet their additive manufacturing(AM)is plagued by significant cracking defects.This review investigates crack failure mechanisms... Nickel-based superalloys are indispensable for high-temperature engineering applications,yet their additive manufacturing(AM)is plagued by significant cracking defects.This review investigates crack failure mechanisms in AM nickel-based superalloys,emphasizing methodologies to evaluate crack sensitivity and compositional design strategies to mitigate defects.Key crack types—solidification,liquation,solid-state,stress corrosion,fatigue,and creep-fatigue cracks—are analyzed,with focus on formation mechanisms driven by thermal gradients,solute segregation,and microstructural heterogeneities.Evaluation frameworks such as the Rappaz-Drezet-Gremaud(RDG)criterion,Solidification Cracking Index(SCI),and Strain Age Cracking(SAC)index are reviewed for predicting crack susceptibility through integration of thermodynamic parameters,solidification kinetics,and mechanical properties.Alloy compositional design strategies are presented,including optimization of strengthening elements(Al,Ti),grain boundary modifiers(B,Zr,Re),and impurity control(C,O),which suppress crack initiation and propagation via microstructure refinement and enhanced high-temperature resistance.Computational approaches,such as thermodynamically assisted design,high-throughput experimentation,and machine learning,are highlighted for decoding complex composition-structure-property relationships.Challenges in modeling multi-scale defect interactions and developing unified frameworks for manufacturing-and service-induced cracks are outlined.This review underscores the necessity of integrated computational-experimental strategies to advance reliable AM of nickel-based superalloys,providing insights for defect prediction,alloy optimization,and process control. 展开更多
关键词 Additive manufacturing nickel-based superalloys CRACKING failure mechanism composition design
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Chemical composition and biological activities of Lysimachia capillipes Hemsl
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作者 Ran Guo Ruoming Li +3 位作者 Xiaomeng Zhang Wenhan Wang Yao Zhao Yu Chen 《Asian Journal of Traditional Medicines》 2025年第1期14-29,共16页
Lysimachia capillipes(L.capillipes)Hemsl,belong to primulaceae pearl vegetables genus,is a treasure in traditional Chinese medicine.It has the effects of invigorating qi and tonifying deficiency,dispelling wind and ac... Lysimachia capillipes(L.capillipes)Hemsl,belong to primulaceae pearl vegetables genus,is a treasure in traditional Chinese medicine.It has the effects of invigorating qi and tonifying deficiency,dispelling wind and activating blood,awakening the brain,relieving cough and regulating menstruation.With the development of modern medicine,the active components and therapeutic mechanisms of L.capillipes Hemsl have been gradually revealed.The present report systematically reviews the chemical composition and biological activities of L.capillipes Hemsl,to provide scientific basis and reference for detailed research on L.capillipes Hemsl. 展开更多
关键词 Lysimachia capillipes Hemsl capilliposide chemical composition biological activity
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Comparative effectiveness of lifestyle interventions on children's body composition management:A systematic review and network meta-analysis
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作者 Xiwen Su Mohamed A.Hassan +1 位作者 HyunJoon Kim Zan Gao 《Journal of Sport and Health Science》 2025年第1期38-48,共11页
Purpose:This study aimed to provide comparative evidence on the effectiveness of various lifestyle interventions on body composition management for preschool and school-aged children.Methods:PubMed(MEDLINE),Embase,CIN... Purpose:This study aimed to provide comparative evidence on the effectiveness of various lifestyle interventions on body composition management for preschool and school-aged children.Methods:PubMed(MEDLINE),Embase,CINAHL,and Web of Science were systematically searched for this network meta-analysis.Randomized controlled studies(RCTs)that included children aged 4-12 years with no physical or mental conditions;performed at least 1 type of lifestyle intervention;reported change in body mass index(BMI),BMI z-score,or body fat percentage(BFP);and were published between January2010 and August 2023 were included.Results:The final analysis included 91 RCTs with aggregate data for 58,649 children.All interventions were categorized into single-arm approaches(physical activity,diet,and behavioral and informational support)and combined arms approaches(bicomponent and multicomponent treatment).Multicomponent treatment showed significant effectiveness on the reduction of BMI(mean deviation(MD)-0.49,95%confidence interval(95%CI):-0.88 to-0.12),BMI z-score(MD=-0.11,95%CI:-0.18 to-0.04),and BFP(MD=-1.69,95%CI:-2.97 to-0.42)compared to the usual care condition.Bicomponent treatment also significantly reduced BMI(MD=-0.28,95%CI:-0.54 to-0.04)and BMI z-score(MD=-0.07,95%CI:-0.12 to-0.02)compared to usual care.Conclusion:Interventions targeting multiple lifestyle components achieved greater reductions in children's BMI and BFP.Among single-component approaches,physical activity engagement emerged as the most effective.These findings should guide practitioners in recommending comprehensive lifestyle modifications for children.Moreover,children with higher initial BMI and body fat levels tend to exhibit more positive responses to lifestyle interventions aimed at managing obesity. 展开更多
关键词 Lifestyle intervention Body composition Preschool-aged children School-aged children
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Exploring the Scientific Connotation of Gypsum in Baihu Decoction Compatibility with Heat-clearing Effect Based on Phase Composition
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作者 Yunyun Wang Zhengxian Zhang +2 位作者 Haotian Peng Huahui Zeng Xiangxiang Wu 《Chinese Medicine and Natural Products》 2025年第1期35-46,共12页
Objective This study aimed to study the effects of different crystalline states of Sheng Shigao(raw gypsum,RG)and its inorganic elements on the antipyretic efficacy of Baihu Decoction(BHT).Methods RG samples calcined ... Objective This study aimed to study the effects of different crystalline states of Sheng Shigao(raw gypsum,RG)and its inorganic elements on the antipyretic efficacy of Baihu Decoction(BHT).Methods RG samples calcined at different temperatures were prepared.The phase composition of RG and Duan Shigao(calcination of gypsum,CG)as well as the changes in phase composition before and after adding water to RG calcined at specific temperatures,were determined using X-ray diffraction(XRD).A fever model was established by subcutaneously injecting 20%yeast suspension(10 mL·kg~(-1))into the backs of rats.The effects of BHT containing RG in different crystalline states on rat body temperature were measured.Serum levels of IL-1β,IL-6,and hypothalamic prostaglandin E2(PGE_2)were detected using ELISA.Serum Ca~(2+)levels were measured using a microplate method.The content of trace elements in RG and CG and the corresponding freeze-dried BHT powder was determined using inductively coupled plasma mass spectrometry(ICP-MS).The complexation of representative inorganic elements with mangiferin,a major active component in BHT,was investigated using UV-Vis spectroscopy and fluorescence spectroscopy.A validation model was established using RAW264.7 mouse macrophages.Drug-containing serum of BHT with different inorganic elements was prepared,and the nitric oxide(NO)levels in the cell supernatant of different treatment groups were measured using the Griess method.The mRNA levels of IL-6,TNF-α,and PGE2in each group were detected using qPCR(real-time fluorescent quantitative PCR).Results After calcination,the phase composition of RG changed,and the content of inorganic elements in RG,CG170(RG calcined at 170°C),and CG350(RG calcined at 350°C)showed similar trends.Compared with RG,the content of Ca,Sr,Al,and Na in CG changed significantly.Compared with BHT,the content of Ca,Sr,Si,and Na in CG changed significantly when incorporated into the formula.Intermolecular interactions confirmed strong binding between mangiferin and Cu~(2+)and Al~(3+).Cu~(2+)and Fe~(3+)exhibited fluorescence quenching effects on mangiferin solution,while Al~(3+)and Zn~(2+)showed strong fluorescence enhancement,with fluorescence intensity increasing by 120-fold and 30-fold,respectively.In vitro evaluation of synergistic anti-inflammatory effects confirmed that Ca,Fe,Cr,Al,and Si exhibited synergistic anti-inflammatory effects.Conclusion The crystalline state of RG has little effect on its antipyretic properties,while Ca,Sr,Na,Fe,and Al are likely the key material bases influencing its efficacy. 展开更多
关键词 GYPSUM Baihu Decoction heat-clearing compatibility of medicines phase composition
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REMARKS ON ASYMPTOTIC EXPANSIONS OF COMPOSITIONS WITH THE ELEMENTARY FUNCTIONS
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作者 LUO Xiao-Yu SHI Yong-Guo JIANG Zhi-Jie 《数学杂志》 2025年第2期131-139,共9页
In this paper,we study asymptotic power series of the composition f(x)=h(g(x)),where g(x)=∑_(n=0)^(∞)b_(n)x^(-n),b_(n)∈R,and h is a given elementary function.The asymptotic expansions have been obtained for the com... In this paper,we study asymptotic power series of the composition f(x)=h(g(x)),where g(x)=∑_(n=0)^(∞)b_(n)x^(-n),b_(n)∈R,and h is a given elementary function.The asymptotic expansions have been obtained for the composition with an exponential or logarithmic function.Using the re-cursive method,we present the asymptotic expansions for the composition with seven trigonometric functions,respectively.As an application,the asymptotic expansions of roots of some equations are given.Computational results show that our recursive formula is more efficient than the method of Lagrange's inverse theorem. 展开更多
关键词 asymptotic expansion asymptotic power series trigonometric function composite function
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