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Is Compositionality a Trivial Principle? 被引量:1
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作者 Richard G. Heck, Jr. 《Frontiers of Philosophy in China》 2013年第1期140-155,共16页
Primarily a response to Paul Horwich's "Composition of Meanings," this paper attempts to refute his claim that compositionality--roughly, the idea that the meaning of a sentence is determined by the meanings of its... Primarily a response to Paul Horwich's "Composition of Meanings," this paper attempts to refute his claim that compositionality--roughly, the idea that the meaning of a sentence is determined by the meanings of its parts and how they are there combined--imposes no substantial constraints on semantic theory or on our conception of the meanings of words or sentences. 展开更多
关键词 compositionality Horwich MEANING SEMANTICS
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Filtering Theories of Truth: Compositionality as a Criterion
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作者 WANG Wenfang 《Frontiers of Philosophy in China》 2013年第1期156-170,共15页
The traditional way to filter out the implausible candidate solutions to the semantic paradoxes is to appeal to the so-called "cost/benefit analyses." Yet it is often tedious and controversial to carry out such anal... The traditional way to filter out the implausible candidate solutions to the semantic paradoxes is to appeal to the so-called "cost/benefit analyses." Yet it is often tedious and controversial to carry out such analyses in detail. Facing this, it would be helpful for us to rely upon some principles to filter out at least something, if not everything, from them. The proposal in this paper is thereby rather simple: We may use principles of compositionality as a "filter" for this purpose. The paper has four sections. In Section 2, the author uses the filter to examine Kripke's fixed-point theory and to thereby show how it works. In Section 3, the author gives more examples from the classical theories of truth to demonstrate the power of the filter. In Section 4, the author addresses the skepticism concerning whether there is any consistent or non-trivial theory of truth that can survive this filtering procedure. A "nearly sufficient" condition for a theory of truth to survive this test is discussed in order to show that at least some consistent or non-trivial theories of truth do indeed survive the filtering procedure. 展开更多
关键词 compositionality semantic paradox fixed-point theory classicaltheory of truth paracomplete theory paraconsistent dialetheism
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Physical activity and exercise within the context of obesity treatment:Enhancing health beyond weight loss
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作者 John M.Jakicic Christian E.Behrens +7 位作者 Sarah E.Deemer Bethany Forseth Christos S.Katsanos Brett S.Nickerson Wagner L.Prado Xuewen Wang Landon S.Deru Renee J.Rogers 《Journal of Sport and Health Science》 2026年第2期31-40,共10页
Overweight and obesity are significant public health concerns worldwide due to their association with many chronic health conditions.This has resulted in the development of various interventions focused on weight loss... Overweight and obesity are significant public health concerns worldwide due to their association with many chronic health conditions.This has resulted in the development of various interventions focused on weight loss to reduce the associated health burden.Physical activity is an important lifestyle behavior associated with enhanced health.Evidence supports that many of the benefits of physical activity are realized independent of initial weight status or whether weight loss is achieved,with some benefits additive to what is achieved with weight loss alone.These benefits include enhanced cardiometabolic,brain,cognitive and psychological health,and others.Moreover,in adults with overweight or obesity,physical activity has independent effects on cardiorespiratory fitness,muscular strength,physical function,and mobility.There are also benefits to body composition,with physical activity improving the quality of key tissues,such as skeletal muscle,which may not occur with diet-induced weight loss.Therefore,physical activity is an important public health target for adults with overweight or obesity to provide a wide range of health benefits that extend beyond those of weight loss alone.However,physical activity recommendations and programming efforts should consider the unique characteristics of adults with overweight or obesity to be most effective,and should support a focus on mobility,physical function,and other health outcomes. 展开更多
关键词 Physical activity EXERCISE OBESITY Body composition Health risk
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Light elements in the Martian core
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作者 Yinfang Yang Shuangmeng Zhai 《Acta Geochimica》 2026年第1期1-14,共14页
The Martian core mainly contains iron,nickel and some light elements.However,controversies remain about the structure and chemical composition of the Martian core due to a lack of samples and marsquake data.Recently,t... The Martian core mainly contains iron,nickel and some light elements.However,controversies remain about the structure and chemical composition of the Martian core due to a lack of samples and marsquake data.Recently,the InSight lander collected long-term marsquake data,which improved the Martian interior structure model.B ased on the preliminary analysis of marsquake data,Mars has a molten liquid core with a radius of around 1700 km.As the Martian core has a smaller density and lower temperature than pure iron at corresponding pressure and temperature conditions,some light elements are introduced to reduce the density and liquidus temperature.With various methods for seismic analysis,in-situ high-pressure and high-temperature experiments,and first-principal calculations,the Martian core composition and evolution models have been updated in the past few years.Here,we review those studies on the light elements in the Martian core from four aspects including(1)high-temperature and high-pressure experiments,(2)marsquake data,(3)mineral physics model with molecular dynamics simulations and(4)cosmochemistry investigation.We discussed the effect of different light elements on the Martian core s density,sound velocity and liquidus temperature.Moreover,the review examines the varieties,abundances and forms of light elements in the Martian core. 展开更多
关键词 Martian core Chemical composition IRON Light elements
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Pore pressure evolution and entrainment mechanism of convex unsaturated colluvial beds with divergent compositions under debris flow overriding
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作者 Pu Li Kaiheng Hu Jiading Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期278-298,共21页
A debris flow descending through an erodible convex colluvial bed,originating from a landslide dam and its upstream deposits,can entrain massive amounts of sediment,dramatically increasing the debris flow volume.Most ... A debris flow descending through an erodible convex colluvial bed,originating from a landslide dam and its upstream deposits,can entrain massive amounts of sediment,dramatically increasing the debris flow volume.Most existing erosion models assume that bed sediments are fully saturated,although this condition is rarely observed in nature.Therefore,a thorough understanding of debris flow overtopping erosion on a convex unsaturated bed is crucial for quantifying disaster risk.In this study,we experimentally investigated the effects of sediment composition,specifically coarse-grain size distribution and fine particle content,on the pore pressure evolution and entrainment of debris flows overriding a convex unsaturated colluvial bed.The average entrainment rate at convex sites for continuously graded bed sediment was higher than its discontinuous counterpart.The measured pore pressures within the unsaturated bed sediments were primarily generated by the passing debris flows.Furthermore,it was found that these pressures decreased as the fine particle content increased and the coarse-grain size of the erodible substrates decreased.When the coarse-grain size of the debris flow was smaller than that of the bed sediment,only a portion of the eroded material was entrained by the moving debris flow.In contrast,when the coarse-grain size of the debris flow was equal to or greater than that of the bed sediment,nearly all of the eroded material was entrained.The findings of this study could contribute to the assessment of hazard amplification and inform the design of mitigation and prevention strategies. 展开更多
关键词 Debris flow Convex colluvial bed Sediment composition Unsaturated bed Pore pressure ENTRAINMENT
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Marine fungal metabolite butyrolactone Ⅰ improves Aβ_(1-42)-induced cognitive impairment in mice via gut-brain axial microbiota remodeling,anti-inflammation,and antioxidation
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作者 Fuyan YANG Longjian ZHOU +5 位作者 Jiahang DENG Yuan WANG Zhiyou YANG Yongping ZHANG Yayue LIU Yi ZHANG 《Journal of Oceanology and Limnology》 2026年第1期386-405,共20页
Alzheimer’s disease(AD)is a complex neurodegenerative disorder associated with changes in inflammation,oxidative stress,and gut microbiota composition.Butyrolactone Ⅰ(BTL-Ⅰ),a fungal metabolite,has shown anti-infla... Alzheimer’s disease(AD)is a complex neurodegenerative disorder associated with changes in inflammation,oxidative stress,and gut microbiota composition.Butyrolactone Ⅰ(BTL-Ⅰ),a fungal metabolite,has shown anti-inflammatory,microbiota regulating,and memory-improving potentials in previous in vitro and AlCl3-induced zebrafish studies.However,its effects of memory-improving and gutbrain axis regulating on Aβ-induced mammalian AD models have not been explored.In this study,intragastric administrated BTL-Ⅰ ameliorated cognitive deficits related to recognition and spatial memory impaired by Aβ_(1-42)intracerebroventricular injection in mice.BTL-Ⅰ maintained gut microbiota balance by increasing the abundance of Blautia,Muribaculaceae,Bacteroides,Akkermansia,etc.,and decreasing CAG-352,Clostridia UCG-014,different Lachnospiraceae groups,etc.,and Firmicutes/Bacteroidota ratio and elevated the levels of short-chain fatty acids.Additionally,it alleviated intestinal oxidative stress,inflammatory responses,and pathological damage.Furthermore,BTL-I reversed Aβ_(1-42)-induced activation of microglia and astrocytes in the hippocampus and inhibited the elevated oxidative stress and proinflammatory cytokines in both plasma and brain.The correlation analysis between the regulated taxa and biomarkers supports the role of gut microbiota in adjusting inflammation,oxidative stress,and memory.In conclusion,BTL-I may serve as a valuable drug lead for treating Alzheimer’s disease by systematically inhibiting microbiota imbalance,inflammation,and oxidative stress along the gut-brain axis. 展开更多
关键词 Alzheimer’s disease butyrolactoneⅠ cognitive deficit microbiota composition oxidative stress NEUROINFLAMMATION
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Compatible Remediation for Vulnerabilities in the Presence and Absence of Security Patches
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作者 Xiaohu Song Zhiliang Zhu 《Computers, Materials & Continua》 2026年第1期297-315,共19页
Vulnerabilities are a known problem in modern Open Source Software(OSS).Most developers often rely on third-party libraries to accelerate feature implementation.However,these libraries may contain vulnerabilities that... Vulnerabilities are a known problem in modern Open Source Software(OSS).Most developers often rely on third-party libraries to accelerate feature implementation.However,these libraries may contain vulnerabilities that attackers can exploit to propagate malicious code,posing security risks to dependent projects.Existing research addresses these challenges through Software Composition Analysis(SCA)for vulnerability detection and remediation.Nevertheless,current solutions may introduce additional issues,such as incompatibilities,dependency conflicts,and additional vulnerabilities.To address this,we propose Vulnerability Scan and Protection(VulnScanPro),a robust solution for detection and remediation vulnerabilities in Java projects.Specifically,VulnScanPro builds a finegrained method graph to identify unreachable methods.The method graph is mapped to the project’s dependency tree,constructing a comprehensive vulnerability propagation graph that identifies unreachable vulnerable APIs and dependencies.Based on this analysis,we propose three solutions for vulnerability remediation:(1)Removing unreachable vulnerable dependencies,thereby resolving security risks and reducing maintenance overhead.(2)Upgrading vulnerable dependencies to the closest non-vulnerable versions,while pinning the versions of transitive dependencies introduced by the vulnerable dependency,in order to mitigate compatibility issues and prevent the introduction of new vulnerabilities.(3)Eliminating unreachable vulnerable APIs,particularly when security patches are either incompatible or absent.Experimental results show that these solutions effectively mitigate vulnerabilities and enhance the overall security of the project. 展开更多
关键词 Open source software vulnerability detection vulnerability remediation software composition analysis software vulnerability
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Partial organic fertilizer substitution and water-saving irrigation can reduce greenhouse gas emissions in aromatic rice paddy by regulating soil microorganisms while increasing yield and aroma
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作者 Ligong Peng Sicheng Deng +6 位作者 Wentao Yi Yizhu Wu Yingying Zhang Xiangbin Yao Pipeng Xing Baoling Cui Xiangru Tang 《Journal of Integrative Agriculture》 2026年第1期273-289,共17页
As the global leader in rice production,China's paddy fields contribute substantially to greenhouse gas emissions through methane(CH_(4))and nitrous oxide(N_(2)O)releases.Aromatic rice cultivation practices have b... As the global leader in rice production,China's paddy fields contribute substantially to greenhouse gas emissions through methane(CH_(4))and nitrous oxide(N_(2)O)releases.Aromatic rice cultivation practices have been optimized to enhance the aroma,so the relationship between its cultivation and greenhouse gas emissions from paddy fields is unclear.To investigate how aroma-enhancing cultivation practices drive microbial community dynamics in aromatic rice paddies and their implications for greenhouse gas emissions,a two-year experiment in five ecological locations(Xingning,Nanxiong,Conghua,Luoding,and Zengcheng)compared two farming practices:partial organic substitution for inorganic fertilizers combined with water-saving irrigation(IOF+W)and traditional cultivation(CK).The CH_(4)and N_(2)O emissions,soil microbial composition and function,global warming potential(GWP),nitrogen use efficiency,yield,and the content of 2-acetyl-1-pyrroline(2-AP)were measured and analyzed.The main purpose was to investigate the impact of IOF+W on CH_(4)and N_(2)O emissions and their relationship with soil microorganisms.The results showed that IOF+W significantly reduced CH_(4)emission fluxes and totals(36.95%)and GWP(31.29%),while significantly increasing N_(2)O emission fluxes and totals(14.82%).The soil microbial community structure was reshaped by the IOF+W treatment,which suppressed methanogens but enhanced the abundances of nitrifying and denitrifying bacteria.Key enzymatic activities involved in CH_(4)production,such as methyl-coenzyme M reductase,formylmethanofuran dehydrogenase,and methyltransferase,decreased.In contrast,the activity of the key CH_(4)-oxidizing enzyme methanol dehydrogenase increased.This shift led to an overall attenuation of the CH_(4)production metabolism while enhancing the CH_(4)oxidation metabolism.In addition,the activities of pivotal enzymes involved in denitrification and nitrification were improved,thus enhancing nitrogen nitrification and denitrification metabolism.Moreover,the IOF+W treatment significantly increased nitrogen use efficiency(47.83%),yield(14.77%),and 2-AP content(13.78%).Therefore,the IOF+W treatment demonstrated good efficacy as a sustainable strategy for achieving productive,green,resource-efficient,and premium-quality aromatic rice cultivation in South China. 展开更多
关键词 greenhouse gas soil microbial composition 2-AP water-saving irrigation nitrogen use efficiency
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Intercropping grain crops with green manure under reduced chemical nitrogen improves the soil carbon stocks by optimizing aggregates in an oasis irrigation area
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作者 Xiaohui Xu Qiang Chai +5 位作者 Falong Hu Wen Yin Zhilong Fan Hanting Li Zhipeng Liu Qiming Wang 《Journal of Integrative Agriculture》 2026年第1期326-338,共13页
Enhancing soil organic carbon(SOC)stocks is a key aspect of modern agriculture,but whether this can be achieved by incorporating legume green manure crops in cereal production to substitute synthetic N fertilizers is ... Enhancing soil organic carbon(SOC)stocks is a key aspect of modern agriculture,but whether this can be achieved by incorporating legume green manure crops in cereal production to substitute synthetic N fertilizers is unknown.This study used a six-year(2017-2022)field study to explore the impacts of intercropping green manure with maize and reducing nitrogen fertilization on SOC stocks,while specifically focusing on the relationship between aggregate composition and carbon sequestration.Maize intercropped with common vetch(M/V),maize intercropped with rapeseed(M/R),and sole maize(M),were each tested at conventional(N2,360 kg ha^(-1))and reduced(N1,270 kg ha^(-1),25% reduced)N application rates.Soil was sampled in 2020,2021,and 2022.Compared with sole maize,intercropping with green manure(M/V and M/R)significantly increased SOC stocks which compensated for any negative effect due to the 25% reduction in N application.Based on 3-year averages,intercropping with M/V and M/R increased the SOC content compared to sole maize(M)by 12.1 and 9.1%,respectively,with intercropping further mitigating the negative impact of reduced nitrogen application.There was no significant difference between M/V and M/R.The SOC content at N1 was reduced by 9.3-10.5%compared to that at N2 in sole maize,but the differences in SOC stocks between N1 and N2 were not significant in the intercropping patterns(M/V and M/R).The intercropped M/V and M/R showed 20.9 and 16.3% higher SOC contents compared to sole maize at N1,with no differences at N2.Intercropping green manure led to a 5.3% greater SOC in the 0-20 cm depth soil in 2022 compared to that in 2020,due to the cumulative effect of two years of green manure intercropping.Intercropping green manure(M/V and M/R)increased the proportion of macroaggregates(>0.25 mm)and aggregate stability while reducing the proportion of microaggregates compared to sole maize under the N1 application.Structural equation modeling indicated that cropping patterns and nitrogen application levels mainly affect SOC indirectly by regulating the composition of macroaggregates and aggregate organic carbon(AOC).Correlation analysis further revealed that the composition of macroaggregates is significantly and positively correlated with the SOC content(R^(2)=0.64).In addition,intercropping green manure can maintain high crop yields by increasing SOC under reduced chemical nitrogen application.The results of this study show that intercropping green manure with grain crops can be a viable measure for increasing SOC sinks and maize productivity by optimizing the aggregate composition with reduced N application in the Hexi Oasis Irrigation Area. 展开更多
关键词 intercropping green manure soil organic carbon soil aggregate composition MAIZE
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Chemical composition and biological activities of Panax notoginseng
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作者 Yu Wang Da Teng +4 位作者 Zixuan Che Ran Guo Meng Zhang Ying Li Yu Chen 《Asian Journal of Traditional Medicines》 2026年第1期31-41,共11页
Panax notoginseng(P.notoginseng),a valuable traditional Chinese medicine,is the dried root of plants in Acanthopanax gracilistylus family,with the effect of dispersing blood stasis,eliminating swelling and relieving p... Panax notoginseng(P.notoginseng),a valuable traditional Chinese medicine,is the dried root of plants in Acanthopanax gracilistylus family,with the effect of dispersing blood stasis,eliminating swelling and relieving pain.With the development of modern medicine,the active ingredients and mechanisms of P.notoginseng have been gradually revealed.The present paper systematically reviews the chemical composition and biological activities of P.nologinseng,to provide a scientific basis and reference for detailed research on P.nologinseng. 展开更多
关键词 Panax notoginseng chemical composition biological activity
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Spatially biased collections and the failure to cover all wild genetic clusters in plant populations under ex situ conservation
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作者 Zhiqiang Xiao Hui Liu +5 位作者 Guiyun Huang Di Wu Liwen Qiu Jinhua Wu Xinzeng Wei Mingxi Jiang 《Plant Diversity》 2026年第1期75-83,共9页
Successful ex situ conservation of plant populations requires a high degree of genetic representativeness.However,spatially biased sampling in ex situ conservation efforts may fail to capture all wild genetic clusters... Successful ex situ conservation of plant populations requires a high degree of genetic representativeness.However,spatially biased sampling in ex situ conservation efforts may fail to capture all wild genetic clusters for species with range-wide genetic structure.To investigate the extent of spatially biased sampling in living collections and the coverage of wild genetic clusters in plant populations under ex situ conservation worldwide,we combined a global synthesis of ex situ conservation efforts with a case study of an endangered riparian plant species,Myricaria laxiflora.Our analysis of ex situ conservation worldwide revealed that the majority(82.6%)of ex situ populations fail to cover all wild genetic clusters,largely due to spatially biased sampling with low geographic coverage.Our case study of M.laxiflora showed that genetic diversity differed between the ex situ and upstream populations,while it was comparable between ex situ populations and other wild populations.However,current ex situ populations did not cover all wild genetic clusters,as the upstream genetic cluster was previously uncollected.Our study suggests that the failure to cover all wild genetic clusters in ex situ populations is a widespread issue,and ex situ populations with high genetic diversity can also fail to cover all wild genetic clusters.In future ex situ conservation programs,both the importance of high genetic diversity and the high coverage of wild genetic clusters should be prioritized. 展开更多
关键词 Conservation genomics Genetic representativeness Ex situ conservation Genetic composition Geographic coverage Spatially biased sampling
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Compositionality in Pablo Picasso’s Poetry
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作者 Enrique Mallen 《Advances in Humanities Research》 2023年第2期1-20,共20页
Pablo Picasso’s poetry expands the expressive power of language through syntactic mechanisms provided in natural grammar.His poems often consist of adjunct phrases,following a technique that recalls his cubist collag... Pablo Picasso’s poetry expands the expressive power of language through syntactic mechanisms provided in natural grammar.His poems often consist of adjunct phrases,following a technique that recalls his cubist collages.The relation between the nuclei of those phrasal constituents as they come in contact remains open,so that readers are free to establish multidirectional semantic associations between them.His poetry is primarily word-oriented.As Picasso once stated,he wanted to compose his poems with“a palette of words,”leaving those words free“to fight it out among themselves”to attain any possible meaning.Such a combinatorial approach to language could be interpreted from the perspective of“linear grammars”as proposed by Culicover and Jackendoff[13],Jackendoff and Wittenberg[20]and Culicover[12]. 展开更多
关键词 PARATAXIS adjuncts apposition compositionality
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Design Guidelines for Composition of Brazing Filler Metals and Evolution Mechanisms of Typical Microstructures 被引量:6
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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:3
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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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Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy 被引量:1
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作者 Tongyue Li Ziliang Xie +5 位作者 Wenjiao Zhou Huan Tong Dawen Yang Anjia Zhang Yuan Wu Xiping Song 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期127-135,共9页
This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),YGdTbDyHo.Results indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with t... This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),YGdTbDyHo.Results indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed homogeneously.Upon hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase precipitated.The alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period observed.The reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral interstices.These results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field. 展开更多
关键词 RARE-EARTH high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves KINETICS
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Substantially improved room-temperature tensile ductility in lightweight refractory Ti-V-Zr-Nb medium entropy alloys by tuning Ti and V content 被引量:4
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作者 Yuefei Jia Gengchen Li +6 位作者 Chang Ren Yongkun Mu Kang Sun Shiwei Wu Xilei Bian Yandong Jia Gang Wang 《Journal of Materials Science & Technology》 2025年第3期234-247,共14页
Lightweight high/medium-entropy alloys(H/MEAs)possess attractive properties such as high strength-to-weight ratios,however,their limited room-temperature tensile ductility hinders their widespread engi-neering impleme... Lightweight high/medium-entropy alloys(H/MEAs)possess attractive properties such as high strength-to-weight ratios,however,their limited room-temperature tensile ductility hinders their widespread engi-neering implementation,for instance in aerospace structural components.This work achieved a transfor-mative improvement of room-temperature tensile ductility in Ti-V-Zr-Nb MEAs with densities of 5.4-6.5 g/cm3,via ingenious composition modulation.Through the systematic co-adjustment of Ti and V contents,an intrinsic ductility mechanism was unveiled,manifested by a transition from predominant intergranular brittle fracture to pervasive ductile dimpled rupture.Notably,the modulated deformation mechanisms evolved from solitary slip toward collaborative multiple slip modes,without significantly compromising strength.Compared to equimolar Ti-V-Zr-Nb,a(Ti1.5V)3ZrNb composition demonstrated an impressive 360%improvement in elongation while sustaining a high yield strength of around 800 MPa.Increasing Ti and V not only purified the grain boundaries by reducing detrimental phases,but also tai-lored the deformation dislocation configurations.These insights expanded the applicability of lightweight HEAs to areas demanding combined high strength and ductility. 展开更多
关键词 DUCTILITY Lightweight high-entropy alloys High strength Composition modulation
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Establishment and verification of anthropogenic speciated VOCs emission inventory of Central China 被引量:3
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作者 Xuan Lu Dong Zhang +9 位作者 Lanxin Wang Shefang Wang Xinran Zhang Yali Liu Keying Chen Xinshuai Song Shasha Yin Ruiqin Zhang Shanshan Wang Minghao Yuan 《Journal of Environmental Sciences》 2025年第3期406-418,共13页
Improving the accuracy of anthropogenic volatile organic compounds(VOCs)emission inventory is crucial for reducing atmospheric pollution and formulating control policy of air pollution.In this study,an anthropogenic s... Improving the accuracy of anthropogenic volatile organic compounds(VOCs)emission inventory is crucial for reducing atmospheric pollution and formulating control policy of air pollution.In this study,an anthropogenic speciated VOCs emission inventory was established for Central China represented by Henan Province at a 3 km×3 km spatial resolution based on the emission factormethod.The 2019 VOCs emission in Henan Provincewas 1003.5 Gg,while industrial process source(33.7%)was the highest emission source,Zhengzhou(17.9%)was the city with highest emission and April and August were the months with the more emissions.High VOCs emission regions were concentrated in downtown areas and industrial parks.Alkanes and aromatic hydrocarbons were the main VOCs contribution groups.The species composition,source contribution and spatial distribution were verified and evaluated through tracer ratio method(TR),Positive Matrix Factorization Model(PMF)and remote sensing inversion(RSI).Results show that both the emission results by emission inventory(EI)(15.7 Gg)and by TRmethod(13.6 Gg)and source contribution by EI and PMF are familiar.The spatial distribution of HCHO primary emission based on RSI is basically consistent with that of HCHO emission based on EI with a R-value of 0.73.The verification results show that the VOCs emission inventory and speciated emission inventory established in this study are relatively reliable. 展开更多
关键词 VOCs verification Species composition Tracer ratio PMF Remote sensing inversion
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Exploring the Scientific Connotation of Gypsum in Baihu Decoction Compatibility with Heat-clearing Effect Based on Phase Composition 被引量:2
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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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Changes in source contributions to the oxidative potential of PM_(2.5)in urban Xiamen,China 被引量:2
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作者 Jia-Min Li Si-Min Zhao +3 位作者 Qi-Yu Miao Shui-Ping Wu Jie Zhang James J.Schwab 《Journal of Environmental Sciences》 2025年第3期342-357,共16页
The toxicity of PM_(2.5)does not necessarily change synchronously with its mass concentration.In this study,the chemical composition(carbonaceous species,water-soluble ions,and metals)and oxidative potential(dithiothr... The toxicity of PM_(2.5)does not necessarily change synchronously with its mass concentration.In this study,the chemical composition(carbonaceous species,water-soluble ions,and metals)and oxidative potential(dithiothreitol assay,DTT)of PM_(2.5)were investigated in 2017/2018 and 2022 in Xiamen,China.The decrease rate of volume-normalized DTT(DTTv)(38%)was lower than that of PM_(2.5)(55%)between the two sampling periods.However,the mass-normalized DTT(DTTm)increased by 44%.Clear seasonal patterns with higher levels in winter were found for PM_(2.5),most chemical constituents and DTTv but not for DTTm.The large decrease in DTT activity(84%−92%)after the addition of EDTA suggested that watersoluble metals were the main contributors to DTT in Xiamen.The increased gap between the reconstructed and measured DTTv and the stronger correlations between the reconstructed/measured DTT ratio and carbonaceous species in 2022were observed.The decrease rates of the hazard index(32.5%)and lifetime cancer risk(9.1%)differed from those of PM_(2.5)and DTTv due to their different main contributors.The PMF-MLR model showed that the contributions(nmol/(min·m^(3)))of vehicle emission,coal+biomass burning,ship emission and secondary aerosol to DTTv in 2022 decreased by 63.0%,65.2%,66.5%,and 22.2%,respectively,compared to those in 2017/2018,which was consistent with the emission reduction of vehicle exhaust and coal consumption,the adoption of low-sulfur fuel oil used on board ships and the reduced production of WSOC.However,the contributions of dust+sea salt and industrial emission increased. 展开更多
关键词 Chemical composition Oxidative potential Interannual change PMF-MLR Source apportionment
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Accurate prediction of magnetocaloric effect in NiMn-based Heusler alloys by prioritizing phase transitions through explainable machine learning 被引量:2
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作者 Yi-Chuan Tang Kai-Yan Cao +7 位作者 Ruo-Nan Ma Jia-Bin Wang Yin Zhang Dong-Yan Zhang Chao Zhou Fang-Hua Tian Min-Xia Fang Sen Yang 《Rare Metals》 2025年第1期639-651,共13页
With the rapid development of artificial intelligence,magnetocaloric materials as well as other materials are being developed with increased efficiency and enhanced performance.However,most studies do not take phase t... With the rapid development of artificial intelligence,magnetocaloric materials as well as other materials are being developed with increased efficiency and enhanced performance.However,most studies do not take phase transitions into account,and as a result,the predictions are usually not accurate enough.In this context,we have established an explicable relationship between alloy compositions and phase transition by feature imputation.A facile machine learning is proposed to screen candidate NiMn-based Heusler alloys with desired magnetic entropy change and magnetic transition temperature with a high accuracy R^(2)≈0.98.As expected,the measured properties of prepared NiMn-based alloys,including phase transition type,magnetic entropy changes and transition temperature,are all in good agreement with the ML predictions.As well as being the first to demonstrate an explicable relationship between alloy compositions,phase transitions and magnetocaloric properties,our proposed ML model is highly predictive and interpretable,which can provide a strong theoretical foundation for identifying high-performance magnetocaloric materials in the future. 展开更多
关键词 NiMn-based Heusler materials Phase transition-type Machine learning Magnetocaloric effect Composition design
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