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Green’s Functions of a Class of Sturm-Liouville Problems with Eigenparameters in Boundary Conditions
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作者 XIAO Lu MU Dan ZHANG Ruifan 《数学理论与应用》 2025年第1期94-106,共13页
In this paper,we study a class of Sturm-Liouville problems,where the boundary conditions involve eigenparameters.Firstly,by defining a new inner product which depends on the transmission conditions,we obtain a new Hil... In this paper,we study a class of Sturm-Liouville problems,where the boundary conditions involve eigenparameters.Firstly,by defining a new inner product which depends on the transmission conditions,we obtain a new Hilbert space,on which the concerned operator A is self-adjoint.Then we construct the fundamental solutions to the problem,obtain the necessary and sufficient conditions for eigenvalues,and prove that the eigenvalues are simple.Finally,we investigate Green’s functions of such problem. 展开更多
关键词 sturm-Liouville problem Eigenparameter-dependent boundary condition greens function
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Leaf functional traits and ecological strategies of common plant species in evergreen broad-leaved forests on Huangshan Mountain
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作者 Ningjie Wang Ting Lv +4 位作者 Lu Wang Shuifei Chen Lei Xie Yanming Fang Hui Ding 《Journal of Forestry Research》 2025年第1期223-243,共21页
The survival strategy of plants is to adjust their functional traits to adapt to the environment.However,these traits and survival strategies of evergreen broad-leaved forest species are not well understood.This study... The survival strategy of plants is to adjust their functional traits to adapt to the environment.However,these traits and survival strategies of evergreen broad-leaved forest species are not well understood.This study examined 10 leaf functional traits(LFTs)of 70 common plant species in an evergreen broad-leaved forest in Huangshan Mountain to decipher their adaptive strategies.The phylogenetic signals of these LFTs were assessed and phylogenetically independent contrasts(PIC)and correlation analyses were carried out.LFTs were analyzed to determine their CSR(C:competitor,S:stress-tolerator,R:ruderal)strategies.The results show that plant species exhibit different leaf functional traits and ecological strategies(nine strategies were identified;the most abundant were S/CS and S/CSR strategies).Some traits showed significant phylogenetic signals,indicating the effect of phylogeny on LFTs to an extent.Trait variations among species suggest distinct adaptation strategies to environmental changes.The study species were mainly clustered on the C-S strategy axis,with a high S component.Species leaning toward the C-strategy end(e.g.,deciduous species),favored a resource acquisition strategy characterized by higher specific leaf area(SLA),greater nutrient contents(N and P),lower leaf dry matter content(LDMC),and reduced nutrient utilization efficiency(C:N and C:P).Conversely,species closer to the S-strategy end(e.g.,evergreen species)usually adopted a resource conservative strategy with trait combinations contrary to those of C-strategy species.Overall,this study corroborated the applicability of the CSR strategy at a local scale and provides insights into the varied trait combinations and ecological strategies employed by plant species to adapt to their environment.These findings contribute to a better understanding of the mechanisms involved in biodiversity maintenance. 展开更多
关键词 Leaf functional traits Phylogenetic signals Phylogenetically independent contrasts CsR ecological strategy
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3D Printing of Tough Hydrogel Scaffolds with Functional Surface Structures for Tissue Regeneration
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作者 Ke Yao Gaoying Hong +11 位作者 Ximin Yuan Weicheng Kong Pengcheng Xia Yuanrong Li Yuewei Chen Nian Liu Jing He Jue Shi Zihe Hu Yanyan Zhou Zhijian Xie Yong He 《Nano-Micro Letters》 SCIE EI CAS 2025年第2期18-45,共28页
Hydrogel scaffolds have numerous potential applications in the tissue engineering field.However,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and hi... Hydrogel scaffolds have numerous potential applications in the tissue engineering field.However,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical properties.Inspired by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this gap.First,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent biocompatibility.Furthermore,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell growth.Interestingly,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT strategies.Animal experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries. 展开更多
关键词 3D printing Tough hydrogel scaffold functional surface structure Tissue regeneration BIOMATERIALs
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Boosting high-performance in Zr-rich side protonic solid oxide electrolysis cells by optimizing functional interlayer
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作者 Chunmei Tang Ning Wang +3 位作者 Sho Kitano Hiroki Habazaki Yoshitaka Aoki Siyu Ye 《Green Energy & Environment》 SCIE EI CAS 2025年第1期150-160,共11页
Protonic solid oxide electrolysis cells(P-SOECs)are a promising technology for water electrolysis to produce green hydrogen.However,there are still challenges related key materials and anode/electrolyte interface.P-SO... Protonic solid oxide electrolysis cells(P-SOECs)are a promising technology for water electrolysis to produce green hydrogen.However,there are still challenges related key materials and anode/electrolyte interface.P-SOECs with Zr-rich electrolyte,called Zr-rich side P-SOECs,possess high thermodynamically stability under high steam concentrations but the large reaction resistances and the current leakage,thus the inferior performances.In this study,an efficient functional interlayer Ba_(0.95)La_(0.05)Fe_(0.8)Zn_(0.2)O_(3-δ)(BLFZ)in-between the anode and the electrolyte is developed.The electrochemical performances of P-SOECs are greatly enhanced because the BLFZ can greatly increase the interface contact,boost anode reaction kinetics,and increase proton injection into electrolyte.As a result,the P-SOEC yields high current density of 0.83 A cm^(-2) at 600℃ in 1.3 Vamong all the reported Zr-rich side cells.This work not only offers an efficient functional interlayer for P-SOECs but also holds the potential to achieve P-SOECs with high performances and long-term stability. 展开更多
关键词 functional interlayer Zr-rich side electrolyte Protonic solid oxide electrolysis cells Current density Faradaic efficiency
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Public-Key Function-Private Inner-Product Predicate Encryption from Pairings
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作者 WAN Ming WANG Geng GU Da-Wu 《密码学报(中英文)》 北大核心 2025年第1期227-246,共20页
This study constructs a function-private inner-product predicate encryption(FP-IPPE)and achieves standard enhanced function privacy.The enhanced function privacy guarantees that a predicate secret key skf reveals noth... This study constructs a function-private inner-product predicate encryption(FP-IPPE)and achieves standard enhanced function privacy.The enhanced function privacy guarantees that a predicate secret key skf reveals nothing about the predicate f,as long as f is drawn from an evasive distribution with sufficient entropy.The proposed scheme extends the group-based public-key function-private predicate encryption(FP-PE)for“small superset predicates”proposed by Bartusek et al.(Asiacrypt 19),to the setting of inner-product predicates.This is the first construction of public-key FP-PE with enhanced function privacy security beyond the equality predicates,which is previously proposed by Boneh et al.(CRYPTO 13).The proposed construction relies on bilinear groups,and the security is proved in the generic bilinear group model. 展开更多
关键词 predicate encryption function privacy inner product generic group model
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A Review of MAX Series Materials:From Diversity,Synthesis,Prediction,Properties Oriented to Functions
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作者 Jian Zhang Ru Jia +5 位作者 Kar Ban Tan Jiaming Li Shichong Xu Guobing Ying Wenjuan Han Ming Lu 《Nano-Micro Letters》 2025年第7期410-451,共42页
MAX series materials,as non-van der Waals layered multi-element compounds,contribute remarkable regulated properties and functional dimension,combining the features of metal and ceramic materials due to their inherent... MAX series materials,as non-van der Waals layered multi-element compounds,contribute remarkable regulated properties and functional dimension,combining the features of metal and ceramic materials due to their inherently laminated crystal structure that Mn+1Xn slabs are intercalated with A element layers.Oriented to the functional requirements of information,intelligence,electrification,and aerospace in the new era,how to accelerate MAX series materials into new quality productive forces?The systematic enhancement of knowledge about MAX series materials is intrinsic to understanding its low-dimensional geometric structure characteristics,and physical and chemical properties,revealing the correlation of composition,structure,and function and further realizing rational design based on simulation and prediction.Diversity also brings complexity to MAX materials research.This review provides substantial tabular information on(Ⅰ)MAX’s research timeline from 1960 to the present,(Ⅱ)structure diversity and classification convention,(Ⅲ)synthesis route exploration,(Ⅳ)prediction based on theory and machine learning,(Ⅴ)properties,and(Ⅵ)functional applications.Herein,the researchers can quickly locate research content and recognize connections and differences of MAX series materials.In addition,the research challenges for the future development of MAX series materials are highlighted. 展开更多
关键词 MAX materials DIVERsITY synthetic strategy PREDICTION function
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Critical station identification of metro networks based on the integrated topological-functional algorithm:A case study of Chengdu
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作者 Zi-Qiang Zeng Sheng-Jie He Wang Tian 《Chinese Physics B》 2025年第2期509-520,共12页
As a key mode of transportation, urban metro networks have significantly enhanced urban traffic environments and travel efficiency, making the identification of critical stations within these networks increasingly ess... As a key mode of transportation, urban metro networks have significantly enhanced urban traffic environments and travel efficiency, making the identification of critical stations within these networks increasingly essential. This study presents a novel integrated topological-functional(ITF) algorithm for identifying critical nodes, combining topological metrics such as K-shell decomposition, node information entropy, and neighbor overlapping interaction with the functional attributes of passenger flow operations, while also considering the coupling effects between metro and bus networks. Using the Chengdu metro network as a case study, the effectiveness of the algorithm under different conditions is validated.The results indicate significant differences in passenger flow patterns between working and non-working days, leading to varying sets of critical nodes across these scenarios. Moreover, the ITF algorithm demonstrates a marked improvement in the accuracy of critical node identification compared to existing methods. This conclusion is supported by the analysis of changes in the overall network structure and relative global operational efficiency following targeted attacks on the identified critical nodes. The findings provide valuable insight into urban transportation planning, offering theoretical and practical guidance for improving metro network safety and resilience. 展开更多
关键词 critical node metro network topological structure functional operation
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A FUNCTIONAL ORLICZ BUSEMANN-PETTY CENTROID INEQUALITY FOR LOG-CONCAVE FUNCTIONS
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作者 Xiao LI Jiazu ZHOU 《Acta Mathematica Scientia》 2025年第1期52-71,共20页
In this paper,the Orlicz centroid function for log-concave functions is introduced.A rearrangement inequality of the Orlicz centroid function for log-concave functions is obtained.The rearrangement inequality implies ... In this paper,the Orlicz centroid function for log-concave functions is introduced.A rearrangement inequality of the Orlicz centroid function for log-concave functions is obtained.The rearrangement inequality implies the Orlicz Busemann-Petty centroid inequality of Lutwak,Yang and Zhang[23]. 展开更多
关键词 centroid bodies Busemann-Petty centroid inequality log-concave functions steiner symmetrization
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Algorithm for computing time correlation functions in non-stationary complex dynamic systems
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作者 Jiu Zhang Lifu Jin +4 位作者 Bo Zheng Xiongfei Jiang Tingting Chen Cong Xu Yanqing Hu 《Chinese Physics B》 2025年第3期77-83,共7页
For non-stationary complex dynamic systems,a standardized algorithm is developed to compute time correlation functions,addressing the limitations of traditional methods reliant on the stationary assumption.The propose... For non-stationary complex dynamic systems,a standardized algorithm is developed to compute time correlation functions,addressing the limitations of traditional methods reliant on the stationary assumption.The proposed algorithm integrates two-point and multi-point time correlation functions into a unified framework.Further,it is verified by a practical application in complex financial systems,demonstrating its potential in various complex dynamic systems. 展开更多
关键词 complex dynamic systems non-stationary states time correlation functions
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Evaluation of physicochemical and functional properties of protein isolates from 5 edible mushroom species
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作者 Zheng Qian Mengdie Yang +4 位作者 Xiao Chen Qiping Zhan Lei Zhong Qiuhui Hu Liyan Zhao 《Food Science and Human Wellness》 2025年第2期671-682,共12页
Edible mushroom proteins are the promising ones with the advantages of complete essential amino acid profile and multiple functional activities.To reinforce their applications in functional food development,this study... Edible mushroom proteins are the promising ones with the advantages of complete essential amino acid profile and multiple functional activities.To reinforce their applications in functional food development,this study comprehensively evaluated the physicochemical and functional properties of protein isolates from 5 mushroom species,i.e.,Pleurotus eryngii(PEP),Pleurotus ostreatus(POP),Lentinula edodes(LEP),Flammulina velutipes(FVP)and Hypsizygus marmoreus(HMP).Results showed that PEP,LEP,FVP,POP and HMP exhibited better protein solubility(PS),water holding capacity(WHC),emulsification activity index(EAI),and foaming capacity(FC)than those of soybean protein and pea protein isolates(PPI).PEP(51.95%)and POP(49.15%)had a higher amount ofβ-sheet structure.Principal component analysis and correlation analysis showed that the seven proteins could be divided into 3 clusters,and WHC,EAI and FC were significantly positively correlated with PS andβ-sheet.The least gelation concentration of PEP(16%)and FVP(16%)at p H 6.0 and 7.0 was similar to PPI,and PEP showed better hardness,springiness and rheological properties than other proteins gels.Overall,our study showed that 5 edible mushroom proteins possessed excellent functionalities(except for gelling capacity),which provided novel insights on unexploited sources of mushroom proteins used as protein-based foods in the food industry. 展开更多
关键词 Edible mushroom proteins Physicochemical properties functional properties Gelling properties
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Insights into the doping functions on redox chemistry of layered Ni-rich cathodes
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作者 Zhenxing Wang Yong Chen 《Journal of Energy Chemistry》 2025年第3期386-412,共27页
In pursuit of low cost and long life for lithium-ion batteries in electric vehicles,the most promising strategy is to replace the commercial LiCoO_(2)with a high-energy-density Ni-rich cathode.However,the irreversible... In pursuit of low cost and long life for lithium-ion batteries in electric vehicles,the most promising strategy is to replace the commercial LiCoO_(2)with a high-energy-density Ni-rich cathode.However,the irreversible redox couples induce rapid capacity decay,poor long-term cycling life,vast gas evolution,and unstable structure transformations of the Ni-rich cathode,limiting its practical applications.Element doping has been considered as the most promising strategy for addressing these issues.However,the relationships between element doping functions and redox chemistry still remain confused.To clarify this connection,this review places the dynamic evolution of redox couples(Li^(*),Ni^(2+)/Ni^(3+)/Ni^(4+)-e^(-),O^(2-)/O^(n-)/O_(2)-e^(-))as the tree trunk.The material structure,degradation mechanisms,and addressing element doping strategies are considered as the tree branches.This comprehensive summary aims to provide an overview of the current understanding and progress of Ni-rich cathode materials.In the last section,promising strategies based on element doping functions are provided to encourage the practical application of Ni-rich cathodes.These strategies also offer a new approach for the development of other intercalated electrode materials in Na and K-based battery systems. 展开更多
关键词 Doping functions Redox chemistry Ni-rich cathode Phase transition structural stability
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Nutritional and therapeutic benefits of coconut milk and its potential as a plant-based functional yogurt alternative:a review
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作者 Gengghatarani Gengan Nurul Solehah Mohd Zaini +6 位作者 Nazamid Saari Anis Shobirin Meor Hussin Ahmad Haniff Jaafar Hanan Hasan Elicia Jitming Lim Wan Abd Al Qadr Imad Wan-Mohtar Muhamad Hafiz Abd Rahim 《Food Science and Human Wellness》 2025年第1期64-77,共14页
Plant-based milks are on the rise due to an increased awareness of their sustainability and health benefits.Currently,dairy milk is the most nutritionally complete beverage,but it suffers from the presence of indigest... Plant-based milks are on the rise due to an increased awareness of their sustainability and health benefits.Currently,dairy milk is the most nutritionally complete beverage,but it suffers from the presence of indigestible lactose and allergenic proteins.Coconut milk has been around for a long time,but its application is limited due to a perceived lack of specific nutrients,high saturated fat levels,and low acceptability.Recent evidence indicates,however,that the saturated fat and other plant-based components found in coconut milk are good for metabolic outcomes and brain health.The conversion of coconut milk to yoghurt will further improve its functionality by boosting its existing nutritional qualities.In this article,the nutritional value of coconut milk,as well as its potential downsides,its application as yoghurt,and suggestions for enhancing its nutritional functionality will be examined. 展开更多
关键词 Coconut milk Plant-based yoghurt Diabetes NEURODEGENERATIVE saturated fat functional food Probiotic
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Droughts and windstorms due to climate change increase variability in species and trait composition of a subtropical monsoon evergreen broadleaf forest in China
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作者 Wenjing Chen Lei Liu +6 位作者 Daijun Liu Josep Penuelas Guoyi Zhou Zhen Yu Anchi Wu Zhurong Wu Langqin Hua 《Forest Ecosystems》 2025年第1期11-19,共9页
Background:Climate change is accelerating alterations in forest species and community composition worldwide,especially following extreme events like severe droughts and windstorms.Understanding these effects on subtro... Background:Climate change is accelerating alterations in forest species and community composition worldwide,especially following extreme events like severe droughts and windstorms.Understanding these effects on subtropical forests is crucial for conservation and forest management,but it remains unclear whether the impacts are stochastic or deterministic.Methods:We analyzed a unique dataset from a 1-ha permanent plot in a subtropical monsoon broadleaf evergreen forest in China,monitored over 26 years with six surveys from 1994 to 2020.The forest has been free from anthropogenic disturbances for over 400 years.In each survey,we measured all trees with a diameter at breast height(DBH)≥1 cm,and recorded 11 plant functional traits relating to photosynthesis,wood properties,water use,and nutrient dynamics.Using this data,we calculated species and trait dispersion,assessing short-term(~5years)and long-term(26 years)trends in species and trait composition following severe droughts and windstorm events.Results:Severe droughts,and subsequent droughts,increased both species and trait dispersion,while species composition converged,and trait dispersion remained relatively stable throughout the recovery period.Windstorm events led to increased species dispersion but decreased trait dispersion.We observed a clear directional shift in both species and trait composition under these climatic stressors,with a more pronounced increase in trait dispersion compared to species dispersion.Conclusion:In the short term(~5 years),severe droughts and windstorms increased species composition divergence,while trait composition responses varied.Over 26 years,deterministic processes mainly drove community composition changes,especially for trait composition,although stochastic processes also played a role.These findings suggest enhancing forest resilience to climatic stressors by protecting adaptive species or increasing species diversity in management practices. 展开更多
关键词 Community dynamics functional traits Community composition Deterministic processes Climate change
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GENERALIZED COUNTING FUNCTIONS AND COMPOSITION OPERATORS ON WEIGHTED BERGMAN SPACES OF DIRICHLET SERIES
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作者 Min HE Maofa WANG Jiale CHEN 《Acta Mathematica Scientia》 2025年第2期291-309,共19页
In this paper,we study composition operators on weighted Bergman spaces of Dirichlet series.We first establish some Littlewood-type inequalities for generalized mean counting functions.Then we give sufficient conditio... In this paper,we study composition operators on weighted Bergman spaces of Dirichlet series.We first establish some Littlewood-type inequalities for generalized mean counting functions.Then we give sufficient conditions for a composition operator with zero characteristic to be bounded or compact on weighted Bergman spaces of Dirichlet series.The corresponding sufficient condition for compactness in the case of positive characteristics is also obtained. 展开更多
关键词 generalized counting function Dirichlet series composition operator weighted Bergman space
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A WKB method based on parabolic cylinder function for very-low-frequency sound propagation in deep ocean
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作者 Jian-Kang Zhan Sheng-Chun Piao +3 位作者 Li-Jia Gong Yang Dong Yong-Chao Guo Guang-Xue Zheng 《Chinese Physics B》 2025年第3期433-446,共14页
A Wentzel-Kramers-Brillouin(WKB)method is introduced for obtaining a uniform asymptotic solution for underwater sound propagation at very low frequencies in deep ocean.The method utilizes a mode sum and employs the re... A Wentzel-Kramers-Brillouin(WKB)method is introduced for obtaining a uniform asymptotic solution for underwater sound propagation at very low frequencies in deep ocean.The method utilizes a mode sum and employs the reference functions method to describe the solution to the depth-separated wave equation approximately using parabolic cylinder functions.The conditions for the validity of this approximation are also discussed.Furthermore,a formula that incorporates waveguide effects for the modal group velocity is derived,revealing that boundary effects at very low frequencies can have a significant impact on the propagation characteristics of even low-order normal modes.The present method not only offers improved accuracy compared to the classical WKB approximation and the uniform asymptotic approximation based on Airy functions,but also provides a wider range of depth applicability.Additionally,this method exhibits strong agreement with numerical methods and offers valuable physical insights.Finally,the method is applied to the study of very-low-frequency sound propagation in the South China Sea,leading to sound transmission loss predictions that closely align with experimental observations. 展开更多
关键词 WKB method normal modes very-low-frequency sound propagation parabolic cylinder function
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Random Green's Function Method for Large-Scale Electronic Structure Calculation
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作者 汤明发 刘畅 +4 位作者 张爱霞 张青云 翟佳羽 袁声军 柯友启 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第5期23-29,共7页
We report a linear-scaling random Green's function(rGF) method for large-scale electronic structure calculation. In this method, the rGF is defined on a set of random states and is efficiently calculated by projec... We report a linear-scaling random Green's function(rGF) method for large-scale electronic structure calculation. In this method, the rGF is defined on a set of random states and is efficiently calculated by projecting onto Krylov subspace. With the rGF method, the Fermi–Dirac operator can be obtained directly, avoiding the polynomial expansion to Fermi–Dirac function. To demonstrate the applicability, we implement the rGF method with the density-functional tight-binding method. It is shown that the Krylov subspace can maintain at small size for materials with different gaps at zero temperature, including H_(2)O and Si clusters. We find with a simple deflation technique that the rGF self-consistent calculation of H_(2)O clusters at T = 0 K can reach an error of~ 1 me V per H_(2)O molecule in total energy, compared to deterministic calculations. The rGF method provides an effective stochastic method for large-scale electronic structure simulation. 展开更多
关键词 CALCULATION function METHOD
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Function,mechanism of action,metabolism,and commercial application of Lonicera japonica:a review
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作者 Xinli Yang Dan Yan 《Food Science and Human Wellness》 2025年第3期783-805,共23页
Lonicera japonica(honeysuckle)is a traditional Chinese medicinal food,in which the main active ingredients are phenolic acids,polysaccharides,flavonoids,and volatile oils.They have various biological activities,includ... Lonicera japonica(honeysuckle)is a traditional Chinese medicinal food,in which the main active ingredients are phenolic acids,polysaccharides,flavonoids,and volatile oils.They have various biological activities,including antiviral,antibacterial,antioxidant,hypoglycemic and lipid-lowering,and anti-inflammatory effects.This review summarizes the health effects and pharmacodynamic mechanisms of L.japonica extracts and the major active ingredients in these extracts,and the structures,metabolic process in vivo,and biotransformation processes of these compounds.In addition,the current status of the development of L.japonica-related functional foods is summarized.The aim is to provide a theoretical basis and reference for the further development and use of the active ingredients in L.japonica as functional foods for disease prevention and treatment. 展开更多
关键词 Lonicera japonica extract and functional components Health effects MECHANIsMs Commercial application
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Electronic interactions between neighboring functionalized guest Sb single atoms and Pt clusters enhance CO tolerance
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作者 Wenkang Miao Ronghui Hao +10 位作者 Lu Gan Wanyin Xu Zihan Wang Wenxin Lin Heguang Liu Yinchun Lyu Qianqian Li Jinyang Xi Anmin Nie Jinsong Wu Hongtao Wang 《Journal of Energy Chemistry》 2025年第2期733-743,I0016,共12页
Platinum-based(Pt)catalysts are notoriously susceptible to deactivation in industrial chemical processes due to carbon monoxide(CO)poisoning.Overcoming this poisoning deactivation of Pt-based catalysts while enhancing... Platinum-based(Pt)catalysts are notoriously susceptible to deactivation in industrial chemical processes due to carbon monoxide(CO)poisoning.Overcoming this poisoning deactivation of Pt-based catalysts while enhancing their catalytic activity,selectivity,and durability remains a major challenge.Herein,we propose a strategy to enhance the CO tolerance of Pt clusters(Pt_n)by introducing neighboring functionalized guest single atoms(such as Fe,Co,Ni,Cu,Sb,and Bi).Among them,antimony(Sb)single atoms(SAs)exhibit significant performance enhancement,achieving 99%CO selectivity and 33.6%CO_(2)conversion at 450℃,Experimental results and density functional theory(DFT)calculations indicate the optimization arises from the electronic interaction between neighboring functionalized Sb SAs and Pt clusters,leading to optimal 5d electron redistribution in Pt clusters compared to other functionalized guest single atoms.The redistribution of 5d electrons weaken both theσdonation andπbackdonation interactions,resulting in a weakened bond strength with CO and enhancing catalyst activity and selectivity.In situ environmental transmission electron microscopy(ETEM)further demonstrates the exception thermal stability of the catalyst,even under H_(2)at 700℃.Notably,the functionalized Sb SAs also improve CO tolerance in various heterogenous catalysts,including Co/CeO_(2),Ni/CeO_(2),Pt/Al_(2)O_(3),and Pt/CeO_(2)-C.This finding provides an effective approach to overcome the primary challenge of CO poisoning in Pt-based catalysts,making their broader applications in various industrial catalysts. 展开更多
关键词 functionalized guest single atoms Pt cluster CO tolerance Electronic effect In-situ TEM
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The application and perspective of NMR and MS based strategies for functional compounds mining in medicinal and dietary plants
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作者 Bodou Zhang Sheng Li +6 位作者 Zhenzhen Liang Yinling Wei Jing Dong Hongyan Wen Lingli Guo Xiaojiang Hao Yu Zhang 《Food Science and Human Wellness》 2025年第1期50-63,共14页
Medicinal and dietary plants provide numerous nutritional and functional compounds and also have various potential health benefits to humanity.The specific and efficient techniques for accurate identification of nutri... Medicinal and dietary plants provide numerous nutritional and functional compounds and also have various potential health benefits to humanity.The specific and efficient techniques for accurate identification of nutritional compounds and functional metabolites is crucial for the development of functional foods from medicinal and dietary plants.Nuclear magnetic resonance(NMR)and mass spectrometry(MS)are indispensable and essential technologies that provide an unsurpassed wealth of untargeted identification,quantitative and qualitative analysis,and structural information in the study of food and plant products.In the past decade,the rapid development of modern analytical technology has led to the emergence of new approaches and strategies for natural products discovery.Especially the application of novel NMRand MS-based identification and dereplication strategies aided by artificial intelligence and machine learning algorithms have brought about a significant shift in the natural products discovery process.These developments and changes in the natural products filed have given us insights into how to accurately target and mining nutritional,functional,and bioactive compounds.Thus,we have summarized recent research on novel NMR and MS based strategies and methods focusing on functional compounds,accurate identification and efficient discovery mainly in medicinal and dietary plants.This review could provide a comprehensive perspective for a better understanding of novel strategies and methods based on NMR and MS technologies,which could provide valuable insights and ideas for functional compounds mining. 展开更多
关键词 Nuclear magnetic resonance(NMR) Mass spectrometry(Ms) New strategies functional compounds MINING
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Green synthesis of glycolic acid through the electrocatalytic reduction of oxalic acid over black TiO_(2): An experimental and theoretical study
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作者 Hugo Olvera-Vargas Oscar Andrés Jaramillo-Quintero +4 位作者 Luis Darío Alarcón León Orlando Castro-Ocampo Christian A.Celaya Marina E.Rincón Jesús Muñiz 《Journal of Energy Chemistry》 2025年第1期544-556,共13页
Herein,we present the electrocatalytic four-electron hydrogenation of oxalic acid into glycolic acid using black TiO_(2)as an electrocatalyst.Oxalic acid is an abundant compound found in several sources of organic was... Herein,we present the electrocatalytic four-electron hydrogenation of oxalic acid into glycolic acid using black TiO_(2)as an electrocatalyst.Oxalic acid is an abundant compound found in several sources of organic waste.The results showed a high selectivity of black TiO_(2)toward glycolic acid,with the formation of glyoxylic acid being the rate-limiting step (glyoxylic acid is the two-electron intermediate).The highest Faradaic efficiency (FE) of 69.6%±8.3% was achieved at 10.2 mA cm^(-2)in 4 h of electrolysis using an H-type cell operated at room temperature,with 50.2%±3.8% of oxalic acid conversion (degradation kinetic constant k=0.0042±0.0001 min-1),58.8%±7.0%of reaction yield and 1.2±0.18 g L-1of glycolic acid production.A theoretical model of black TiO_(2)coming from anatase TiO_(2)was implemented by introducing Ti3+defects,which gave black TiO_(2)the theoretical capability to easily transform oxalic acid into glycolic acid as experimentally observed.The reaction mechanism was supported and described in detail by density functional theory calculations,which revealed that surface Ti^(3+)states were the main catalytic sites.This is the first time that a detailed step-by-step mechanism at the atomic level has been proposed for this electrocatalytic reaction,which represents a valuable contribution to the understanding of this process of high energy/environmental interest.This is also the first time that black TiO_(2)has been used as an electrocatalyst for this sustainable process. 展开更多
关键词 Chemical energy storage Electrochemical hydrogenation Density functional theory Renewable energy Oxalic acid
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