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Biodiversity and Enzyme Activity of Indigenous Cellulolytic and Amylolytic Bacteria in Decayed Mangrove Stem Waste Product at Waai Seashore, Ambon Island
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作者 Utami Sri Hastuti Kristin Sangur Henny Nurul Khasanah 《Journal of Agricultural Science and Technology(B)》 2015年第4期252-256,共5页
Mangrove (Sonneratia spp.) could be found at Waai seashore, Ambon island. The remainder of the mangrove stem will be decayed and become the waste product. Some indigenous bacteria species that live in the decayed ma... Mangrove (Sonneratia spp.) could be found at Waai seashore, Ambon island. The remainder of the mangrove stem will be decayed and become the waste product. Some indigenous bacteria species that live in the decayed mangrove stem waste product have cellulolytic and amylolytic characters. This research was done to: (1) identify and determine the cellulolytic bacteria species; (2) identify and determine the amylolytic bacteria species; (3) determine the cellulolytic bacteria species that have the highest cellulase activity; (4) determine the amylolytic bacteria species that have the highest amylase activity. This research was conducted at the Microbiology Laboratory, Department of Biology, State University of Malang, Microbiology Laboratory, Faculty of Medicine, Brawijaya University and Chemistry Laboratory, Muhammadiyah Malang University. In the experiment, 25 g sample were grinded and diluted in 225 mL nutrient broth to get 101 suspension. Then the suspension was diluted gradually until 101~. The suspension was inoculated on nutrient agar medium with 0.1 mL each, and incubated in 37 ~C during 24 h. Each bacteria colony was isolated and identified to know whether it was cellulolytic or amylolytic bacteria. Afterward, the cellulase activity as well as the amylase activity was analyzed. The research results show that: (1) there are four cellulolytic bacteria species, i.e., Micrococcus luteus, Bacillus pumilus, Planococcus citreus and Bacillus cereus; (2) there are four amylolytic bacteria species, i.e., Bacillus firmus, Nitrobacter sp., Bacillus mycoides and Pseudomonas aeruginosa; (3) Bacillus cereus has the highest cellulase activity; (4) Nitrobacter sp. has the highest amylase activity. 展开更多
关键词 BIODIVERSITY cellulolytic bacteria amylolytic bacteria decayed mangrove stem waste product.
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Behavior of Decayed Spruce (Picea abies) during Kraft Pulping
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作者 Markku Halonen Raimo Alén 《Paper And Biomaterials》 2020年第4期1-7,共7页
This study indicated that by applying an improved classification system to decayed large-diameter Norway spruce(Picea abies)wood,its use as raw material for kraft pulping without loss of pulp quality could be essentia... This study indicated that by applying an improved classification system to decayed large-diameter Norway spruce(Picea abies)wood,its use as raw material for kraft pulping without loss of pulp quality could be essentially increased.This is based on the fact that although the cooking yield of decayed spruce material which has been sorted according to these new recommendations is somewhat lower and Kappa number higher than those of sound wood material,the greatest part of the decayed stem(the outer part of the stem)contains long-fiber wood material which produces pulp of good quality.Therefore,large-diameter spruce logs can also be separately used,for example,in the manufacture of reinforcement pulp. 展开更多
关键词 Norway spruce kraft pulping wood decay fungal decay soft rot
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Multi-scale investigation on staged deterioration mechanism of sliding-zone soils induced by reservoir fluctuations 被引量:2
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作者 Haiyan Zhang Xinli Hu +5 位作者 Lanxing Li Hongchao Zheng Deshan Cui Chunye Ying Chu Xu Honghua Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2539-2551,共13页
Water level fluctuations in the reservoir deteriorate soils and rocks on the bank landslides by drying-wetting(D-W)cycles,which results in a significant decrease in mechanical properties.A comprehensive understanding ... Water level fluctuations in the reservoir deteriorate soils and rocks on the bank landslides by drying-wetting(D-W)cycles,which results in a significant decrease in mechanical properties.A comprehensive understanding of deterioration mechanism of sliding-zone soils is of great significance for interpreting the deformation behavior of landslides.However,quantitative investigation on the deterioration characteristics of soils considering the structural evolution under D-W cycles is still limited.Here,we carry out a series of laboratory tests to characterize the multi-scale deterioration of sliding-zone soils and reveal the mechanism of shear strength decay under D-W cycles.Firstly,we describe the micropores into five grades by scanning electron microscope and observe a critical change in porosity after the first three cycles.We categorize the mesoscale cracks into five classes using digital photography and observe a stepwise increase in crack area ratio.Secondly,we propose a shear strength decay model based on fractal theory which is verified by the results of consolidated undrained triaxial tests.Cohesion and friction angle of sliding-zone soils are found to show different decay patterns resulting from the staged evolution of structure.Then,structural deterioration processes including cementation destruction,pores expansion,aggregations decomposition,and clusters assembly are considered to occur to decay the shear strength differently.Finally,a three-stage deterioration mechanism associated with four structural deterioration processes is revealed,which helps to better interpret the intrinsic mechanism of shear strength decay.These findings provide the theoretical basis for the further accurate evaluation of reservoir landslides stability under water level fluctuations. 展开更多
关键词 Sliding-zone soils Drying-wetting cycles Structural evolution Shear strength decay Deterioration mechanism
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Testing Validity of the Isobaric Multiplet Mass Equation in T=3 Isospin Septet
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作者 LIU Junhao HUA Xiang ZHAO Xi 《原子核物理评论》 北大核心 2025年第2期218-222,共5页
The validity of the isobaric multiplet mass equation(IMME)is of foundamental importance due to the basic concept of isospin.Recently,a serious breakdown was found in the A=54,T=3,isospin septet,the largest isospin sys... The validity of the isobaric multiplet mass equation(IMME)is of foundamental importance due to the basic concept of isospin.Recently,a serious breakdown was found in the A=54,T=3,isospin septet,the largest isospin system where the validity of IMME have been tested up to now.Inspired by this work,I revist the mass of some isobaric analogue states with the help of recent results from advanced mass measurement experiment.It is found that the IMME holds well in A=50 and 46 isospin septet and the coefficients of IMME also follow the systematic trends.Mass excess value for^(50)Ni and^(46)Fe,is predicted to be-3932(20)keV and 898(67)keV,respectively. 展开更多
关键词 ISOSPIN IMME nuclear mass βdecay proton drip-line
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Detector array with digital data acquisition system for charged-particle decay studies
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作者 Hao Jian Xin-Xing Xu +40 位作者 Kai-Long Wang Jia-Jian Liu Chao-Yi Fu Peng-Jie Li Yan-Yun Yang Guang-Xin Zhang Kang Wang Fang-Fang Duan Long-Hui Ru Guang-Shun Li Bing Ding Yun-Hua Qiang Cen-Xi Yuan Jun-Bing Ma Shi-Wei Xu Yu-Feng Gao Rui Fan Fan-Chao Dai Si-Xian Zha Hao-Fan Zhu Jin-Hai Li Shu-Lian Qin Zhi-Fang Chang Cheng Kong He-Xuan Yan Hao-Wei Xu Jia-Long Ning Bo-Ren Liu Jie Zhou Yu-Dong Chen Bo-Shuai Cai Yu-Ting Wang Hong-Yi Wu Zhi-Xuan Wang Dong-Sheng Hou Hu-Shan Xu Xiao-Hong Zhou Yu-Hu Zhang Meng Wang Zheng-Guo Hu Jenny Lee 《Nuclear Science and Techniques》 2025年第4期140-150,共11页
A state-of-the-art detector array with a digital data acquisition system has been developed for charged-particle decay studies,includingβ-delayed protons,αdecay,and direct proton emissions from exotic proton-rich nu... A state-of-the-art detector array with a digital data acquisition system has been developed for charged-particle decay studies,includingβ-delayed protons,αdecay,and direct proton emissions from exotic proton-rich nuclei.The digital data acquisition system enables precise synchronization and processing of complex signals from various detectors,such as plastic scintillators,silicon detectors,and germaniumγdetectors.The system's performance was evaluated using theβdecay of^(32)Ar and its neighboring nuclei,produced via projectile fragmentation at the first Radioactive Ion Beam Line in Lanzhou(RIBLL1).Key measurements,including the half-life,charged-particle spectrum,andγ-ray spectrum,were obtained and compared with previous results for validation.Using the implantation–decay method,the isotopes of interest were implanted into two doublesided silicon strip detectors,where their subsequent decays were measured and correlated with preceding implantations using both position and time information.This detection system has potential for further applications,including the study ofβ-delayed charged-particle decay and direct proton emissions from even more exotic proton-rich nuclei. 展开更多
关键词 β-delayed proton decay Double-sided silicon strip detector High-purity germanium detector Digital data acquisition system Implantation–decay correlation
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Research Progress of Nanotechnology on Efficient and Green Technologies for Wood Preservation:A Review
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作者 Yuxin He Yixin Li +2 位作者 Qiaoguang Li Wenqing Xiao Guijun Xie 《Journal of Renewable Materials》 2025年第4期699-718,共20页
Wood,recognized as a renewable and environmentally sustainable material,plays a crucial role as an alternative energy resource within the construction industry.However,it is highly susceptible to mold and decay fungi,... Wood,recognized as a renewable and environmentally sustainable material,plays a crucial role as an alternative energy resource within the construction industry.However,it is highly susceptible to mold and decay fungi,which can lead to surface discoloration and potentially compromise the structural integrity of wood.The advancement of nanotechnology has introduced innovative strategies for wood protection,enhancing its performance while imparting additional properties.Various approaches including nanosized metals,polymer nanocomposite and coating treatments are actively being explored in this field.Furthermore,integrating bio-based materials with nanotechnology offers a green and sustainable method for wood preservation.This paper provides an analysis,discussion,and synthesis of the applications of nanotechnology in wood protection along with its antifungal mechanisms,thereby contributing novel insights into the research landscape surrounding this topic. 展开更多
关键词 WOOD wood decay antimicrobial surfaces hydrophobic surface NANOTECHNOLOGY quaternary ammonium compounds
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Capacitance decay mechanism of vanadium nitride supercapacitor electrodes in KOH electrolytes
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作者 Xiu-Li Li Hao Song +7 位作者 Yong-Hui Zhang Yu-Lei Ren Qi-Fei Guo Zi-Huan Tang Zhuo Li Biao Gao Paul K.Chu Kai-Fu Huo 《Rare Metals》 2025年第6期3909-3919,共11页
Vanadium nitride(VN)is a promising pseudocapacitive material due to the high theoretical capacity,rapid redox Faradaic kinetics,and appropriate potential window.Although VN shows large pseudocapacitance in alkaline el... Vanadium nitride(VN)is a promising pseudocapacitive material due to the high theoretical capacity,rapid redox Faradaic kinetics,and appropriate potential window.Although VN shows large pseudocapacitance in alkaline electrolytes,the electrochemical instability and capacity degradation of VN electrode materials present significant challenges for practical applications.Herein,the capacitance decay mechanism of VN is investigated and a simple strategy to improve cycling stability of VN supercapacitor electrodes is proposed by introducing VO_(4)^(3-)anion in KOH electrolytes.Our results show that the VN electrode is electrochemical stabilization between-1.0and-0.4 V(vs.Hg/Hg O reference electrode)in 1.0 MKOH electrolyte,but demonstrates irreversible oxidation and fast capacitance decay in the potential range of-0.4 to0 V.In situ electrochemical measurements reveal that the capacitance decay of VN from-0.4 to 0 V is ascribed to the irreversible oxidation of vanadium(V)of N–V–O species by oxygen(O)of OH^(-).The as-generated oxidization species are subsequently dissolved into KOH electrolytes,thereby undermining the electrochemical stability of VN.However,this irreversible oxidation process could be hindered by introducing VO_(4)^(3-)in KOH electrolytes.A high volumetric specific capacitance of671.9 F.cm^(-3)(1 A.cm^(-3))and excellent cycling stability(120.3%over 1000 cycles)are achieved for VN nanorod electrode in KOH electrolytes containing VO_(4)^(3-).This study not only elucidates the failure mechanism of VN supercapacitor electrodes in alkaline electrolytes,but also provides new insights into enhancing pseudocapacitive energy storage of VN-based electrode materials. 展开更多
关键词 Vanadium nitride Capacitance decay PSEUDOCAPACITANCE Oxidation mechanism SUPERCAPACITORS
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Evaluation of damage evolution in pure magnesium during surrogate high-energy electron irradiation for Brachytherapy seed application
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作者 Hucheng Yu Sichen Dong +7 位作者 Qi Chen Xiaoou Yi Hui Liu Hao Fang Wentuo Han Pingping Liu Somei Ohnuki Farong Wan 《Journal of Magnesium and Alloys》 2025年第7期3104-3121,共18页
Evaluation of damage evolution effects in biodegradable pure Mg was carried out,using transmission electron microscope as surrogate irradiation for high-energy radionuclide β decay in Brachytherapy.Time-dependent qua... Evaluation of damage evolution effects in biodegradable pure Mg was carried out,using transmission electron microscope as surrogate irradiation for high-energy radionuclide β decay in Brachytherapy.Time-dependent quantitative defect production,evolution dynamics,and evolution statistics were revealed in-situ for two prism foils(z=[1.210],[10.10]),in as-received and heat-treated pure Mg,after 300 keV electron irradiation up to 0.468 dpa at R.T.Preferred nucleation of basal-plane interstitial-type 1/6<20.23>loops was confirmed,in addition to a small portion of prism-plane 1/3<11.20>loops.No cavities were found.A higher yield of point defect concentration and a more evident trend of defect coarsening were identified in[1.210]than in[10.10].Pre-existing dislocations(on the orders of 10^(13)−10^(14) m^(−2))in pure Mg resulted in a delay of the first occurrence of visible defects.Defect migration and elastic interactions governed the microstructural evolution of electron irradiation damage in pure Mg,giving rise to events of loop coalescence,growth,and sometimes rotation of habit plane.The influence of incident electron energy can be correlated to the rates of point defect production,and is quantifiable;however,interfered by defect cluster stability,defect mobility,and defect interactions.This forms an important theoretical basis for the application of Mg subjected to MeV-level β-decay radiation in Brachytherapy.The paper concludes with a brief comparison between Mg and conventional Ti casing,outlines the advantages and challenges,and provides reference points for the validation of Mg/Mg-alloys in Brachytherapy seed application. 展开更多
关键词 Magnesium BRACHYTHERAPY Radionuclideβdecay Surrogate irradiation Prism orientation Damage evolution
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STRONG SOLUTION FOR BIPOLAR COMPRESSIBLE NAVIER-STOKES-POISSON SYSTEM WITH UNEQUAL VISCOSITIES IN L^(P)-FRAMEWORK
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作者 Zhigang WU Fuyi XU 《Acta Mathematica Scientia》 2025年第3期1019-1044,共26页
The present paper deals with the Cauchy problem to a two-fluid plasma model with unequal viscosities in any dimension N≥2.Employing the precise spectral analysis for the corresponding linearized system,we prove the g... The present paper deals with the Cauchy problem to a two-fluid plasma model with unequal viscosities in any dimension N≥2.Employing the precise spectral analysis for the corresponding linearized system,we prove the global well-posedness provided that the initial data are close to a stable equilibrium state in critical functional framework which is not related to the energy space.Moreover,the optimal decay rates for the constructed global solution are also established. 展开更多
关键词 BIPOLAR Navier-Stokes-Poission system unequal viscosities global well-posedness optimal decay rates
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Two-plasmon-decay instability stimulated by dual laser beams in inertial confinement fusion
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作者 C.-W.Lian Y.Ji +4 位作者 R.Yan J.Li L.-F.Wang Y.-K.Ding J.Zheng 《Matter and Radiation at Extremes》 2025年第1期48-56,共9页
Two-plasmon-decay instability(TPD)poses a critical target preheating risk in direct-drive inertial confinement fusion.In this paper,TPD collectively driven by dual laser beams consisting of a normal-incidence laser be... Two-plasmon-decay instability(TPD)poses a critical target preheating risk in direct-drive inertial confinement fusion.In this paper,TPD collectively driven by dual laser beams consisting of a normal-incidence laser beam(Beam-N)and a large-angle-incidence laser beam(Beam-L)is investigated via particle-in-cell simulations.It is found that significant TPD growth can develop in this regime at previously unexpected low laser intensities if the intensity of Beam-L exceeds the large-angle-incidence threshold.Both beams contribute to the growth of TPD in a“seed-amplification”manner in which the absolute instability driven by Beam-L provides the seeds that are convectively amplified by Beam-N,making TPD energetically important and causing significant pump depletion and hot-electron generation. 展开更多
关键词 LASER PUMP DECAY
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Status and Prospect of Weak Radiative Hyperon Decays
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作者 Rui-Xiang Shi Zekun Jia +3 位作者 Li-Sheng Geng Haiping Peng Qiang Zhao Xiaorong Zhou 《Chinese Physics Letters》 2025年第3期44-51,共8页
Weak radiative hyperon decays represent a rich interplay between weak interactions and the internal structure of baryons,offering profound insights into Quantum Chromodynamics and weak interactions.Recent experimental... Weak radiative hyperon decays represent a rich interplay between weak interactions and the internal structure of baryons,offering profound insights into Quantum Chromodynamics and weak interactions.Recent experimental observations,particularly from BESIII,have revealed deviations from theoretical predictions.These deviations could signal new physics or the need for refined theoretical models incorporating intermediate resonance effects.This review discusses recent theoretical advancements and key experimental findings,focusing on recent measurements from BESIII and their implications for strong interactions and baryon structure. 展开更多
关键词 structure refined DECAY
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Laser-assistedαdecay of the deformed odd-A nuclei
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作者 Jun-Hao Cheng Qiong Xiao +3 位作者 Jun-Gang Deng Yang-Yang Xu You-Tian Zou Tong-Pu Yu 《Nuclear Science and Techniques》 2025年第4期181-198,共18页
In this study,we explore the impact of state-of-the-art laser fields on theαdecay half-life of deformed ground-state odd-A nuclei within the proton number range of 52–107.The calculations show that the presence of a... In this study,we explore the impact of state-of-the-art laser fields on theαdecay half-life of deformed ground-state odd-A nuclei within the proton number range of 52–107.The calculations show that the presence of a laser field modulates theαdecay half-life by altering theαdecay penetration probability within a limited range.Moreover,the variance in the penetration probability rate of change between even–odd and odd–even nuclei is investigated.Furthermore,we investigate the rate of change of the penetration probability for the same parent nucleus with different neutron numbers,based on the characteristics of the odd-A nucleus.We found that the influence of the laser field on the penetration probability is determined by both the shell effect and odd–even staggering.This research contributes to the understanding of nuanced interactions between laser fields and nuclear decay processes.Therefore,valuable insights for future experiments in laser–nuclear physics are attainable using this study. 展开更多
关键词 αdecay Odd-A nuclei HALF-LIFE Extreme laser field Penetration probability
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Species Diversity of Wood-Decaying Fungi in Karst Regions of Southwest China
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作者 Fan GAO Tinghong TAN +6 位作者 Zhihong LU Na QIU Chenglong LIU Min ZHOU Gongping KANG Hong YANG Chuandong YANG 《Plant Diseases and Pests》 2025年第1期6-12,共7页
[Objectives] To investigate the species diversity of wood-decaying fungi in karst regions of southwest China. [Methods] The karst core regions of southwest China, specifically Guizhou, Guangxi, and Yunnan, were invest... [Objectives] To investigate the species diversity of wood-decaying fungi in karst regions of southwest China. [Methods] The karst core regions of southwest China, specifically Guizhou, Guangxi, and Yunnan, were investigated for the first time to analyze the species diversity characteristics of wood-decaying fungi in this area. This analysis was conducted through a comprehensive 5-year field investigation and systematic identification process. [Results] The wood-decaying fungi exhibited a distinctive species composition and distribution pattern within karst habitats, encompassing significant groups such as Polyporaceae and Hymenochaetaceae. Furthermore, these fungi demonstrated varying functional characteristics across the two ecological types of standing tree decay and wood decay. It was observed that wood-decaying fungi had a significant impact on the material cycle within karst ecosystems by degrading lignin and cellulose. Furthermore, the distribution of species diversity was closely associated with the characteristics of karst geomorphology and the types of vegetation. [Conclusions] This study not only addresses the lack of background data regarding wood-decaying fungi resources in karst regions, but also elucidates the maintenance mechanisms of fragile ecosystems from the perspective of decomposers. It provides a scientific foundation for biodiversity conservation, the prevention and control of forest diseases, and sustainable ecological management in karst regions. 展开更多
关键词 Wood-decaying fungi Karst landform Species diversity Ecological function Decay type
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The Withered Rose and Decay of the South:Symbolic Systems in A Rose for Emily
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作者 MIN Hong-yan 《Journal of Literature and Art Studies》 2025年第5期383-390,共8页
William Faulkner’s Southern Gothic style features fragmented narratives and rich symbolism that explore characters’psychological complexity and the decay of Southern society.In his seminal work exploring Emily Grier... William Faulkner’s Southern Gothic style features fragmented narratives and rich symbolism that explore characters’psychological complexity and the decay of Southern society.In his seminal work exploring Emily Grierson’s tragic life,Faulkner employs a rich symbolic system that transcends mere literary decoration,instead functioning as a complex interpretative lens through which the disintegration of traditional Southern social structures can be understood.This paper argues that the symbolic framework in the narrative not only shapes Emily’s personal tragedy but also serves as a profound metaphorical representation of the collapse of the old Southern civilization-a system marked by rigid social hierarchies,racial tensions,and the slow erosion of aristocratic ideals in the face of inevitable social transformation.By dissecting the intricate symbolic elements-from the decaying mansion to the gothic imagery of death and preservation-this analysis reveals how Faulkner’s symbolic methodology becomes a nuanced historical and psychological commentary on the South’s traumatic transition from an antebellum past to a modernizing present. 展开更多
关键词 Southern Gothic SYMBOLISM civilizational decay William Faulkner
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Space and time estimates of second gradient thermal problems
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作者 J.R.FERNÁNDEZ V.PATA R.QUINTANILLA 《Applied Mathematics and Mechanics(English Edition)》 2025年第7期1403-1416,共14页
We consider the space and time decays of certain problems within the second gradient thermal law.Notably,for this thermal theory,the exponential time decay is precluded.First,the time estimates of polynomial type are ... We consider the space and time decays of certain problems within the second gradient thermal law.Notably,for this thermal theory,the exponential time decay is precluded.First,the time estimates of polynomial type are obtained for both the thermal equation and the one-dimensional thermoelastic system,where the impossibility of localization with respect to time is also established.Then,the space estimates are deduced for the multidimensional thermoelastic problem,which allow to show the exponential decay of the energy. 展开更多
关键词 second gradient theory THERMOELASTICITY spatial estimate polynomial decay
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Characteristics and possible causes of the Meiyu over the Yangtze-Huaihe River Basin in 2023
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作者 Yao Ha Haixia Dai +2 位作者 Shuai Song Yaming Zhao Wei Lu 《Atmospheric and Oceanic Science Letters》 2025年第5期16-21,共6页
The Meiyu in the Yangtze-Huaihe River basin(YHRB)in 2023 was featured by delayed onset and retreat,a shorter duration,and below-normal Meiyu precipitation.The relatively weak cold air invading southward from the mid-t... The Meiyu in the Yangtze-Huaihe River basin(YHRB)in 2023 was featured by delayed onset and retreat,a shorter duration,and below-normal Meiyu precipitation.The relatively weak cold air invading southward from the mid-to-high latitudes in late May-early June contributed to the delayed onset of Meiyu season,and the persistent rainfall caused by Typhoon“Talim”and Super Typhoon“Doksuri”led to the delayed retreat.The westward-shifted and intensified western Pacific subtropical high(WPSH),coupled with the eastward-shifted and strengthened south Asian high(SAH),as well as the Eurasian mid-to-high latitude circulation featuring“two troughs-one ridge”,resulting in the below-average Meiyu precipitation with the heaviest rainfall primally in eastern YHRB.Further analysis indicates that the 2023 Meiyu was influenced by the combined effects of the decaying La Nina,warm sea surface temperature(SST)anomalies in the North Pacific west wind drift area,and less than normal snow cover over the Tibetan Plateau.Warmer than normal ssT in the western Pacific warm pool and the North Pacific westerly drift region favored the narrow meridional circulation at middle latitudes and WPSH,whereas the strengthened SAH and East Asian summer monsoon were impacted by persistently reduced snow cover over the northeastern Tibetan Plateau. 展开更多
关键词 MEIYU Decaying La Niia Westerly wind drift area SNOWCOVER Tibetan Plateau
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On fuzzy modelling of dynamic track behaviour
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作者 Katja Stampka Vincent Radmann +1 位作者 Jannik Theyssen Ennes Sarradj 《Railway Engineering Science》 2025年第3期474-495,共22页
Rolling noise is an important source of railway noise and depends also on the dynamic behaviour of a railway track.This is characterized by the point or transfer mobility and the track decay rate,which depend on a num... Rolling noise is an important source of railway noise and depends also on the dynamic behaviour of a railway track.This is characterized by the point or transfer mobility and the track decay rate,which depend on a number of track parameters.One possible reason for deviations between simulated and measured results for the dynamic track behaviour is the uncertainty of the value of some track parameters used as input for the simulation.This in turn results in an uncertainty in the simulation results.In this contribution,it is proposed to use the general transformation method to assess a uncertainty band for the results.Most relevant input parameters for determining the point input mobility and the track decay rate for a ballasted track are analysed with regard to the uncertainties and for the value of each an interval is determined.Then,the general transformation method is applied to four different simulation methods,working both in the frequency and time domains.For one example track,the resulting uncertainty bands are compared to one dataset with measurements for the point mobility and the track decay rate.In addition,a sensitivity analysis is performed to determine the parameters that significantly influence the overall result.While all four simulation methods produce broad uncertainty bands for the results,none did match the measured results for the point mobility and the track decay rate over the entire frequency range considered.Besides the large influence of the uncertain pad stiffness,it turned out that the rail wear is also a significant source of uncertainty of the results.Overall,it is demonstrated that the proposed approach allows assessing the influence of uncertain input parameters in detail. 展开更多
关键词 Dynamic track behaviour UNCERTAINTY General transformation method Track decay rate Rolling noise
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Suppressing Exciton–Vibration Coupling and Reducing Nonradiative Energy Loss in Conjugated Polymers Through Fluorine Substitution in Side Chains
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作者 Zezhou Liang Lihe Yan +5 位作者 Xiaoming Li Yufei Wang Baofeng Zhao Chao Gao Jinhai Si Hou Xun 《Energy & Environmental Materials》 2025年第3期264-273,共10页
Fluorine(F)substitution in polymers modulates both molecular energy levels and film morphology;however,its impact on exciton–vibrational coupling and molecular reorganization energy is often neglected.Herein,we syste... Fluorine(F)substitution in polymers modulates both molecular energy levels and film morphology;however,its impact on exciton–vibrational coupling and molecular reorganization energy is often neglected.Herein,we systematically investigated F-modified polymers(PBTA-PSF,PBDB-PSF)and their nonfluorinated counterparts(PBTA-PS,PBDB-PS)through simulations and experiments.We found that F atoms effectively lower the vibrational frequency of the molecular skeleton and suppress exciton–vibration coupling,thereby reducing the nonradiative decay rate.Moreover,introducing F atoms significantly decreases the reorganization energy for the S_(0)→S_(1) and S_(0)→cation transitions while increasing the reorganization energy for the S_(1)→S_(0) and cation→S_(0) transitions.These changes facilitate exciton dissociation and reduce the energy loss caused by dissociation and nonradiative recombination of excitons.Additionally,introducing F atoms into polymers enhances theπ–πstacking strength and the crystal coherence length in both neat and blended films,ultimately resulting in improvements in the power conversion efficiency of PBTA-PSF:L8-BO and PBDB-PSF:L8-BO are 16.51%and 17.59%,respectively.This study provides valuable insights for designing organic semiconductor materials to minimize energy loss and achieve a higher power conversion efficiency. 展开更多
关键词 exciton-vibration coupling fluorine substitution nonradiative decay rate reorganization energy
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GLOBAL WELL-POSEDNESS FOR THE 3D INCOMPRESSIBLE HEAT-CONDUCTING MAGNETOHYDRODYNAMIC FLOWS WITH TEMPERATURE-DEPENDENT COEFFICIENTS
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作者 Qingyan LI Zhenhua GUO 《Acta Mathematica Scientia》 2025年第3期951-981,共31页
In this paper,we consider an initial boundary value problem for the nonhomo-geneous heat-conducting magnetohydrodynamic fuids when the viscosityμ,magnetic dif-fusivity v and heat conductivity k depend on the temperat... In this paper,we consider an initial boundary value problem for the nonhomo-geneous heat-conducting magnetohydrodynamic fuids when the viscosityμ,magnetic dif-fusivity v and heat conductivity k depend on the temperature according to μ(0)=°,k(0)=08,v(0)=07,withα,>0,β≥0.We prove the global existence of a unique strong solution provided that ■ is suitably small.In addition,we also get some results of the large-time behavior and exponential decay estimates. 展开更多
关键词 incompressible heat-conducting magnetohydrodynamic equations temperature-dependent coefficients strong solutions global existence exponential decay
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OPTIMAL DECAY RATES FOR THE WEAK SOLUTIONS OF THE FLOCKING PARTICLES COUPLED WITH INCOMPRESSIBLE VISCOUS FLUID MODELS
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作者 Houzhi TANG Shuxing ZHANG Weiyuan ZOU 《Acta Mathematica Scientia》 2025年第2期659-683,共25页
This paper studies the global existence and large-time behaviors of weak solutions to the kinetic particle model coupled with the incompressible Navier-Stokes equations in IR3.First,we obtain the global weak solution ... This paper studies the global existence and large-time behaviors of weak solutions to the kinetic particle model coupled with the incompressible Navier-Stokes equations in IR3.First,we obtain the global weak solution using the characteristic and energy methods.Then,under the small assumption of the mass of the particle,we show that the solutions decay at the algebraic time-decay rate.Finally,it is also proved that the above rate is optimal.It should be remarked that if the particle in the coupled system vanishes(i.e.f=O),our works coincide with the classical results by Schonbek[32](J Amer Math Soc,1991,4:423-449),which can be regarded as a generalization from a single fuid model to the two-phase fluid one. 展开更多
关键词 Cucker-Smale model incompressible Navier-Stokes equations weak solution large-time behavior optimal decay rates
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