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Revealing the correlation between adsorption energy and activation energy to predict the catalytic activity of metal oxides for HMX using DFT
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作者 Xiurong Yang Chi Zhang +6 位作者 Wujing Jin Zhaoqi Guo Hongxu Gao Shiyao Niu Fengqi Zhao Bo Liu Haixia Ma 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期262-270,共9页
Traditional selection of combustion catalysis is time-consuming and labor-intensive.Theoretical calculation is expected to resolve this problem.The adsorption energy of HMX and O atoms on 13 metal oxides was calculate... Traditional selection of combustion catalysis is time-consuming and labor-intensive.Theoretical calculation is expected to resolve this problem.The adsorption energy of HMX and O atoms on 13 metal oxides was calculated using DMol3,since HMX and O are key substances in decomposition process.And the relationship between the adsorption energy of HMX,O on metal oxides(TiO_(2),Al_(2)O_(3),PbO,CuO,Fe_(2)O_(3),Co_(3)O_(4),Bi_(2)O_(3),NiO)and experimental T30 values(time required for the decomposition depth of HMX to reach 30%)was depicted as volcano plot.Thus,the T30 values of other metal oxides was predicted based on their adsorption energy on volcano plot and validated by previous experimental data.Further,the adsorption energy of HMX on ZrO_(2)and MnO_(2)was predicted based on the linear relationship between surface energy and adsorption energy,and T30 values were estimated based on volcano plot.The apparent activation energy data of HMX/MgO,HMX/SnO_(2),HMX/ZrO_(2),and HMX/MnO_(2)obtained from DSC experiments are basically consistent with our predicted T30 values,indicating that it is feasible to predict the catalytic activity based on the adsorption calculation,and it is expected that these simple structural properties can predict adsorption energy to reduce the large quantities of computation and experiment cost. 展开更多
关键词 Density functional theory HMX Metal oxides Adsorption energy Activation energy
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The chemical characteristics of different sodium iron ethylenediaminetetraacetate sources and their relative bioavailabilities for broilers fed with a conventional corn‑soybean meal diet
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作者 Shengchen Wang Bingxin Wu +8 位作者 Ling Zhu Weiyun Zhang Liyang Zhang We Wu Jiaqi Wu Yun Hu Tingting Li Xiaoyan Cui Xugang Luo 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期826-843,共18页
Background Our previous studies demonstrated that divalent organic iron(Fe)proteinate sources with higher complexation or chelation strengths as expressed by the greater quotient of formation(Qf)values displayed highe... Background Our previous studies demonstrated that divalent organic iron(Fe)proteinate sources with higher complexation or chelation strengths as expressed by the greater quotient of formation(Qf)values displayed higher Fe bioavailabilities for broilers.Sodium iron ethylenediaminetetraacetate(NaFeEDTA)is a trivalent organic Fe source with the strongest chelating ligand EDTA.However,the bioavailability of Fe when administered as NaFeEDTA in broilers and other agricultural animals remains untested.Herein,the chemical characteristics of 12 NaFeEDTA products were determined.Of these,one feed grade NaFeEDTA(Qf=2.07×10^(8)),one food grade NaFeEDTA(Qf=3.31×10^(8)),and one Fe proteinate with an extremely strong chelation strength(Fe-Prot ES,Qf value=8,590)were selected.Their bioavailabilities relative to Fe sulfate(FeSO_(4)·7H_(2)O)for broilers fed with a conventional corn-soybean meal diet were evaluated during d 1 to 21 by investigating the effects of the above Fe sources and added Fe levels on the growth performance,hematological indices,Fe contents,activities and gene expressions of Fe-containing enzymes in various tissues of broilers.Results NaFeEDTA sources varied greatly in their chemical characteristics.Plasma Fe concentration(PI),transferrin saturation(TS),liver Fe content,succinate dehydrogenase(SDH)activities in liver,heart,and kidney,catalase(CAT)activity in liver,and SDH mRNA expressions in liver and kidney increased linearly(P<0.05)with increasing levels of Fe supplementation.However,differences among Fe sources were detected(P<0.05)only for PI,liver Fe content,CAT activity in liver,SDH activities in heart and kidney,and SDH mRNA expressions in liver and kidney.Based on slope ratios from multiple linear regressions of the above indices on daily dietary analyzed Fe intake,the average bioavailabilities of Fe-Prot ES,feed grade NaFeEDTA,and food grade NaFeEDTA relative to the inorganic FeSO_(4)·7H_(2)O(100%)for broilers were 139%,155%,and 166%,respectively.Conclusions The bioavailabilities of organic Fe sources relative to FeSO_(4)·7H_(2)O were closely related to their Qf values,and NaFeEDTA sources with higher Qf values showed higher Fe bioavailabilities for broilers fed with a conventional corn-soybean meal diet. 展开更多
关键词 BROILERS Chelation strengths Fe-containing enzymes NAFEEDTA relative bioavailabilities
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Optimal investment based on relative performance and weighted utility
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作者 WANG Lei DONG Ying-hui HUA Chun-rong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第2期328-342,共15页
This paper studies the optimal portfolio allocation of a fund manager when he bases decisions on both the absolute level of terminal relative performance and the change value of terminal relative performance compariso... This paper studies the optimal portfolio allocation of a fund manager when he bases decisions on both the absolute level of terminal relative performance and the change value of terminal relative performance comparison to a predefined reference point. We find the optimal investment strategy by maximizing a weighted average utility of a concave utility and an Sshaped utility via a concavification technique and the martingale method. Numerical results are carried out to show the impact of the extent to which the manager pays attention to the change of relative performance related to the reference point on the optimal terminal relative performance. 展开更多
关键词 relative performance weighted utility S-shaped utility CONCAVIFICATION
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Relative orbit determination algorithm of space targets with passive observation
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作者 DAI Chenchao QIANG Hongfu +2 位作者 ZHANG Degang HU Shaolei GONG Baichun 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期793-804,共12页
Angles-only relative orbit determination for space non-cooperative targets based on passive sensor is subject to weakly observable problem of the relative state between two spacecraft. Previously, the evidence for ang... Angles-only relative orbit determination for space non-cooperative targets based on passive sensor is subject to weakly observable problem of the relative state between two spacecraft. Previously, the evidence for angles-only observability was found by using cylindrical dynamics, however, the solution of orbit determination is still not provided. This study develops a relative orbit determination algorithm with the cylindrical dynamics based on differential evolution. Firstly, the relative motion dynamics and line-of-sight measurement model for nearcircular orbit are established in cylindrical coordinate system.Secondly, the observability is qualitatively analyzed by using the dynamics and measurement model where the unobservable geometry is found. Then, the angles-only relative orbit determination problem is modeled into an optimal searching frame and an improved differential evolution algorithm is introduced to solve the problem. Finally, the proposed algorithm is verified and tested by a set of numerical simulations in the context of highEarth and low-Earth cases. The results show that initial relative orbit determination(IROD) solution with an appropriate accuracy in a relative short span is achieved, which can be used to initialize the navigation filter. 展开更多
关键词 angles-only measurement relative orbit determination cylindrical coordinate differential evolution
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An Experimental Study on the Effect of a Nanofluid on Oil-Water Relative Permeability
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作者 Hui Tian Dandan Zhao +3 位作者 Yannan Wu Xingyu Yi Jun Ma Xiang Zhou 《Fluid Dynamics & Materials Processing》 EI 2024年第6期1265-1277,共13页
The low porosity and low permeability of tight oil reservoirs call for improvements in the current technologies for oil recovery.Traditional chemical solutions with large molecular size cannot effectively flow through... The low porosity and low permeability of tight oil reservoirs call for improvements in the current technologies for oil recovery.Traditional chemical solutions with large molecular size cannot effectively flow through the nanopores of the reservoir.In this study,the feasibility of Nanofluids has been investigated using a high pressure high temperature core-holder and nuclear magnetic resonance(NMR).The results of the experiments indicate that the specified Nanofluids can enhance the tight oil recovery significantly.The water and oil relative permeability curve shifts to the high water saturation side after Nanofluid flooding,thereby demonstrating an increase in the water wettability of the core.In the Nanofluid flooding process the oil recovery was enhanced by 15.1%,compared to waterflooding stage.The T2 spectra using the NMR show that after Nanofluid flooding,a 7.18%increment in oil recovery factor was gained in the small pores,a 4.9%increase in the middle pores,and a 0.29%increase in the large pores.These results confirm that the Nanofluids can improve the flow state in micro-sized pores inside the core and increase the ultimate oil recovery factor. 展开更多
关键词 Tight oil reservoir NANOFLUID relative permeability nuclear magnetic resonance T2 spectrum
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Properties of collective flow and pion production in intermediate-energy heavy-ion collisions with a relativistic quantum molecular dynamics model
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作者 Si-Na Wei Zhao-Qing Feng 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第1期155-169,共15页
The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(LQMD.RMF). Using the LQMD.RMF, the properties of collective flow and pion production were investigated sys... The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(LQMD.RMF). Using the LQMD.RMF, the properties of collective flow and pion production were investigated systematically for nuclear reactions with various isospin asymmetries. The directed and elliptic flows of the LQMD.RMF are able to describe the experimental data of STAR Collaboration. The directed flow difference between free neutrons and protons was associated with the stiffness of the symmetry energy, that is, a softer symmetry energy led to a larger flow difference. For various collision energies, the ratio between the π^(-) and π^(+) yields increased with a decrease in the slope parameter of the symmetry energy. When the collision energy was 270 MeV/nucleon, the single ratio of the pion transverse momentum spectra also increased with decreasing slope parameter of the symmetry energy in both nearly symmetric and neutron-rich systems.However, it is difficult to constrain the stiffness of the symmetry energy with the double ratio because of the lack of threshold energy correction on the pion production. 展开更多
关键词 Heavy-ion collision Collective flow Pion production Symmetry energy relativistic mean field
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Serum proteins differentially expressed in gestational diabetes mellitus assessed using isobaric tag for relative and absolute quantitation proteomics
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作者 Wei-Li Cao Cui-Ping Yu Ling-Li Zhang 《World Journal of Clinical Cases》 SCIE 2024年第8期1395-1405,共11页
BACKGROUND As a well-known fact to the public,gestational diabetes mellitus(GDM)could bring serious risks for both pregnant women and infants.During this important investigation into the linkage between GDM patients a... BACKGROUND As a well-known fact to the public,gestational diabetes mellitus(GDM)could bring serious risks for both pregnant women and infants.During this important investigation into the linkage between GDM patients and their altered expression in the serum,proteomics techniques were deployed to detect the differentially expressed proteins(DEPs)of in the serum of GDM patients to further explore its pathogenesis,and find out possible biomarkers to forecast GDM occurrence.METHODS Subjects were divided into GDM and normal control groups according to the IADPSG diagnostic criteria.Serum samples were randomly selected from four cases in each group at 24-28 wk of gestation,and the blood samples were identified by applying iTRAQ technology combined with liquid chromatography-tandem mass spectrometry.Key proteins and signaling pathways associated with GDM were identified by bioinformatics analysis,and the expression of key proteins in serum from 12 wk to 16 wk of gestation was further verified using enzyme-linked immunosorbent assay (ELISA).RESULTS Forty-seven proteins were significantly differentially expressed by analyzing the serum samples between the GDMgravidas as well as the healthy ones. Among them, 31 proteins were found to be upregulated notably and the rest16 proteins were downregulated remarkably. Bioinformatic data report revealed abnormal expression of proteinsassociated with lipid metabolism, coagulation cascade activation, complement system and inflammatory responsein the GDM group. ELISA results showed that the contents of RBP4, as well as ANGPTL8, increased in the serumof GDM gravidas compared with the healthy ones, and this change was found to initiate from 12 wk to 16 wk ofgestation.CONCLUSION GDM symptoms may involve abnormalities in lipid metabolism, coagulation cascade activation, complementsystem and inflammatory response. RBP4 and ANGPTL8 are expected to be early predictors of GDM. 展开更多
关键词 Gestational diabetes mellitus Liquid chromatography-tandem mass spectrometry Isobaric tag for relative and absolute quantitation PROTEOMICS BIOMARKER
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Correlation of work function and stacking fault energy through Kelvin probe force microscopy and nanohardness in diluteα-magnesium
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作者 Yigit Türe Ali Arslan Kaya +2 位作者 Hüseyin Aydin Jiang Peng Servet Turan 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期237-250,共14页
Electronic interactions of the Group 2A elements with magnesium have been studied through the dilute solid solutions in binary Mg-Ca,Mg-Sr and Mg-Ba systems.This investigation incorporated the difference in the‘Work ... Electronic interactions of the Group 2A elements with magnesium have been studied through the dilute solid solutions in binary Mg-Ca,Mg-Sr and Mg-Ba systems.This investigation incorporated the difference in the‘Work Function'(ΔWF)measured via Kelvin Probe Force Microscopy(KPFM),as a property directly affected by interatomic bond types,i.e.the electronic structure,nanoindentation measurements,and Stacking Fault Energy values reported in the literature.It was shown that the nano-hardness of the solid-solutionα-Mg phase changed in the order of Mg-Ca>Mg-Sr>Mg-Ba.Thus,it was shown,by also considering the nano-hardness levels,that SFE of a solid-solution is closely correlated with its‘Work Function'level.Nano-hardness measurements on the eutectics andΔWF difference between eutectic phases enabled an assessment of the relative bond strength and the pertinent electronic structures of the eutectics in the three alloys.Correlation withΔWF and at least qualitative verification of those computed SFE values with some experimental measurement techniques were considered important as those computational methods are based on zero Kelvin degree,relatively simple atomic models and a number of assumptions.As asserted by this investigation,if the results of measurement techniques can be qualitatively correlated with those of the computational methods,it can be possible to evaluate the electronic structures in alloys,starting from binary systems,going to ternary and then multi-elemental systems.Our investigation has shown that such a qualitative correlation is possible.After all,the SFE values are not treated as absolute values but rather become essential in comparative investigations when assessing the influences of alloying elements at a fundamental level,that is,free electron density distributions.Our study indicated that the principles of‘electronic metallurgy'in developing multi-elemental alloy systems can be followed via practical experimental methods,i.e.ΔWF measurements using KPFM and nanoindentation. 展开更多
关键词 Mg alloys Dilute alloys Work function Stacking fault energy Kelvin probe force microscopy Short range order Miedema NANOINDENTATION EUTECTICS
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Quantitative distinction of the relative actions of climate change and human activities on vegetation evolution in the Yellow River Basin of China during 1981-2019 被引量:4
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作者 LIU Yifeng GUO Bing +3 位作者 LU Miao ZANG Wenqian YU Tao CHEN Donghua 《Journal of Arid Land》 SCIE CSCD 2023年第1期91-108,共18页
Under the combined influence of climate change and human activities,vegetation ecosystem has undergone profound changes.It can be seen that there are obvious differences in the evolution patterns and driving mechanism... Under the combined influence of climate change and human activities,vegetation ecosystem has undergone profound changes.It can be seen that there are obvious differences in the evolution patterns and driving mechanisms of vegetation ecosystem in different historical periods.Therefore,it is urgent to identify and reveal the dominant factors and their contribution rates in the vegetation change cycle.Based on the data of climate elements(sunshine hours,precipitation and temperature),human activities(population intensity and GDP intensity)and other natural factors(altitude,slope and aspect),this study explored the spatial and temporal evolution patterns of vegetation NDVI in the Yellow River Basin of China from 1989 to 2019 through a residual method,a trend analysis,and a gravity center model,and quantitatively distinguished the relative actions of climate change and human activities on vegetation evolution based on Geodetector model.The results showed that the spatial distribution of vegetation NDVI in the Yellow River Basin showed a decreasing trend from southeast to northwest.During 1981-2019,the temporal variation of vegetation NDVI showed an overall increasing trend.The gravity centers of average vegetation NDVI during the study period was distributed in Zhenyuan County,Gansu Province,and the center moved northeastwards from 1981 to 2019.During 1981-2000 and 2001-2019,the proportion of vegetation restoration areas promoted by the combined action of climate change and human activities was the largest.During the study period(1981-2019),the dominant factors influencing vegetation NDVI shifted from natural factors to human activities.These results could provide decision support for the protection and restoration of vegetation ecosystem in the Yellow River Basin. 展开更多
关键词 vegetation evolution driving mechanisms climate change human activities relative actions Geodetector Yellow River Basin
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Relative energy zero ratio-based approach for identifying pulse-like ground motions 被引量:2
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作者 Liu Ping Li Ning +2 位作者 Ma Hua Xie Lili Zhou Baofeng 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2020年第1期1-16,共16页
Pulse-like ground motions are capable of inflicting significant damage to structures. Efficient classification of pulse-like ground motion is of great importance when performing the seismic assessment in near-fault re... Pulse-like ground motions are capable of inflicting significant damage to structures. Efficient classification of pulse-like ground motion is of great importance when performing the seismic assessment in near-fault regions. In this study, a new method for identifying the velocity pulses is proposed, based on different trends of two parameters: the short-time energy and the short-time zero crossing rate of a ground motion record. A new pulse indicator, the relative energy zero ratio(REZR), is defined to qualitatively identify pulse-like features. The threshold for pulse-like ground motions is derived and compared with two other identification methods through statistical analysis. The proposed procedure not only shows good accuracy and efficiency when identifying pulse-like ground motions but also exhibits good performance for classifying records with high-frequency noise and discontinuous pulses. The REZR method does not require a waveform formula to express and fit the potential velocity pulses;it is a purely signal-based classification method. Finally, the proposed procedure is used to evaluate the contribution of pulse-like motions to the total input energy of a seismic record, which dramatically increases the seismic damage potential. 展开更多
关键词 pulse-like ground motion velocity pulse relative energy zero-crossing ratio short-time input energy shorttime zero crossing rate
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Recent Advances on Polyoxometalate-Based Ion-Conducting Electrolytes for Energy-Related Devices 被引量:1
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作者 Dongming Cheng Ke Li +1 位作者 Hongying Zang Jiajia Chen 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第2期262-274,共13页
Solid-state electrolytes have attracted considerable attention in new energyrelated devices due to their high safety and broad application platform.Polyoxometalates(POMs)are a kind of molecular-level cluster compounds... Solid-state electrolytes have attracted considerable attention in new energyrelated devices due to their high safety and broad application platform.Polyoxometalates(POMs)are a kind of molecular-level cluster compounds with unique structures.In recent years,owing to their abundant physicochemical properties(including high ionic conductivity and reversible redox activity),POMs have shown great potential in becoming a new generation of solid-state electrolytes.In this review,an overview is investigated about how POMs have evolved as ion-conducting materials from basic research to novel solid-state electrolytes in energy devices.First,some expressive POM-based ion-conducting materials in recent years are introduced and classified,mainly inspecting their structural and functional relationship.After that,it is further focused on the application of these ionconducting electrolytes in the fields of proton exchange membranes,supercapacitors,and ion batteries.In addition,some properties of POMs(such as inherent dimension,capable of forming stable hydrogen bonds,and reversible bonding to water molecules)enable these functional POM-based electrolytes to be employed in innovative applications such as ion selection,humidity sensing,and smart materials.Finally,some fundamental recommendations are given on the current opportunities and challenges of POM-based ion-conducting electrolytes. 展开更多
关键词 energy devices ion conduction POLYOXOMETALATES solid-state electrolytes
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A review on the synthesis of transition metal nitride nanostructures and their energy related applications 被引量:1
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作者 Qiao Luo Congcong Lu +1 位作者 Lingran Liu Maiyong Zhu 《Green Energy & Environment》 SCIE EI CSCD 2023年第2期406-437,共32页
Transition metal nitrides(TMN)have recently grabbed immensely appealing as ideal active materials in energy storage and catalysis fields on account of their remarkable electrical conductivity,excellent chemical stabil... Transition metal nitrides(TMN)have recently grabbed immensely appealing as ideal active materials in energy storage and catalysis fields on account of their remarkable electrical conductivity,excellent chemical stability,wide band gap and tunable morphology.Both pure TMN and TMN-based materials have been extensively studied concerned with their preparation approaches,nanostructures,and favored performance in various applications.However,the processes towards synthesis of TMN are numerous and complex.Choosing appropriate method to obtain target TMN with desired structure is crucial,which further affects its practical application performance.Herein,this review offers a timely and comprehensive summary of the synthetic ways to TMN and their application in energy related domains.The synthesis section is categorized into in-situ and ex-situ based on where the N element in TMN origins from.Then,overviews on the energy related applications including energy storage,electrocatalysis and photocatalysis are discussed.In the end,the problems to be solved and the development trend of the synthesis and application of transition metal nitrides are prospected. 展开更多
关键词 Transition metal nitride IN-SITU Ex-situ energy storage ELECTROCATALYSIS PHOTOCATALYSIS
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Preliminary results on a near-real-time rock slope damage monitoring system based on relative velocity changes following the September 5,2022 M_(S) 6.8 Luding,China earthquake 被引量:1
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作者 Fan Xie Chen Liang +5 位作者 Shigui Dai Bo Shao Huibao Huang Jinhui Ouyang Li Li Eric Larose 《Earthquake Research Advances》 CSCD 2023年第1期31-36,共6页
Relative seismic velocity change(dv/v)is important for monitoring changes in subsurface material properties and evaluating earthquake-induced rock slope damage in a geological disaster-prone region.In this paper,we pr... Relative seismic velocity change(dv/v)is important for monitoring changes in subsurface material properties and evaluating earthquake-induced rock slope damage in a geological disaster-prone region.In this paper,we present a rapid damage assessment on three slow-moving rock slopes by measuring dv/v decrease caused by the 2022 M_(S) 6.8 Luding earthquake in Southwest China.By applying the stretching method to the cross-correlated seismic wavefields between sensors installed on each slope,we obtain earthquake-induced dv/v decreases of~2.1%,~0.5%,and~0.2%on three slopes at distances ranging from~86 to~370 km to the epicenter,respectively.Moreover,based on seismic data recorded by 16 sensors deployed on the rock slope at a distance of~370 km away from the epicenter,a localized dv/v decease region was observed at the crest of the slope by calculating the spatial dv/v images before and after the earthquake.We also derive an empirical in situ stress sensitivity of -7.29×10^(-8)/Pa by relating the dv/v change to the measured peak dynamic stresses.Our results indicate that a rapid dv/v assessment not only can help facilitate on-site emergency response to earthquakeinduced secondary geological disasters but also can provide a better understanding of the subsurface geological risks under diverse seismic loadings. 展开更多
关键词 relative velocity change Rock slope damage Luding earthquake Space-time evolution
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Effect of Relative Stress on Post-Peak Uniaxial Compression Fracture Energy of Concrete 被引量:4
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作者 王学滨 PANYi-shan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2003年第4期89-92,共4页
Fracture energy in strain softening regime was investigated analytically by considering microstructures interaction and interplay.Based on gradient-dependent plasticity, the thickness of localized band was determined ... Fracture energy in strain softening regime was investigated analytically by considering microstructures interaction and interplay.Based on gradient-dependent plasticity, the thickness of localized band was determined completely and strictly by characteristic length in relation to average grain diameter.After obtaining the plastic shear displacement of the band,the formula on axial response of concrete was proposed and the analytical post-peak fracture energy was deduced.A comparison between present theoretical results and earlier experimental results was carried out and the analytical result is reasonable and has a plausible foundation as considering the localized failure theoretically.Decreasing the relative stress leads to increasing the fracture energy non-linearly.The larger the shear elastic modulus and shear softening modulus,the lower the post-peak fracture energy.A larger fracture energy is caused by a larger thickness of shear band or a larger characteristic length of concrete material.If the inclination angle of the shear band and the compressive strength are not concerned with structural size of specimen,the post-peak fracture energy is size independent. 展开更多
关键词 fracture energy relative stress gradient-dependent plasticity thickness of shear band uniaxial compression characteristic length
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2024 Adult Compendium of Physical Activities:A third update of the energy costs of human activities 被引量:4
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作者 Stephen D.Herrmann Erik A.Willis +10 位作者 Barbara E.Ainsworth Tiago V.Barreira Mary Hastert Chelsea L.Kracht John M.Schuna Jr. Zhenghui Cai Minghui Quan Catrine Tudor-Locke Melicia C.Whitt-Glover David R. Jacobs Jr. 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期6-12,共7页
Background:The Compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across studies.The original version was u... Background:The Compendium of Physical Activities was published in 1993 to improve the comparability of energy expenditure values assigned to self-reported physical activity(PA)across studies.The original version was updated in 2000,and again in 2011,and has been widely used to support PA research,practice,and public health guidelines.Methods:This 2024 update was tailored for adults 19-59 years of age by removing data from those≥60 years.Using a systematic review and supplementary searches,we identified new activities and their associated measured metabolic equivalent(MET)values(using indirect calorimetry)published since 2011.We replaced estimated METs with measured values when possible.Results:We screened 32,173 abstracts and 1507 full-text papers and extracted 2356 PA energy expenditure values from 701 papers.We added303 new PAs and adjusted 176 existing MET values and descriptions to reflect the addition of new data and removal of METs for older adults.We added a Major Heading(Video Games).The 2024 Adult Compendium includes 1114 PAs(912 with measured and 202 with estimated values)across 22 Major Headings.Conclusion:This comprehensive update and refinement led to the creation of The 2024 Adult Compendium,which has utility across research,public health,education,and healthcare domains,as well as in the development of consumer health technologies.The new website with the complete lists of PAs and supporting resources is available at https://pacompendium.com. 展开更多
关键词 ADULTS energy expenditure EXERCISE MET Physical Activities
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Older Adult Compendium of Physical Activities:Energy costs of human activities in adults aged 60 and older 被引量:3
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作者 Erik A.Willis Stephen D.Herrmann +8 位作者 Mary Hastert Chelsea L.Kracht Tiago V.Barreira John M.Schuna Jr. Zhenghua Cai Minghui Quan Scott A.Conger Wendy J.Brown Barbara E.Ainsworth 《Journal of Sport and Health Science》 SCIE CSCD 2024年第1期13-17,F0003,共6页
Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MET)values ... Purpose:To describe the development of a Compendium for estimating the energy costs of activities in adults>60 years(OA Compendium).Methods:Physical activities(PAs)and their metabolic equivalent of task(MET)values were obtained from a systematic search of studies published in 4 sport and exercise databases(PubMed,Embase,SPORTDiscus(EBSCOhost),and Scopus)and a review of articles included in the 2011 Adult Compendium that measured PA in older adults.MET values were computed as the oxygen cost(VO_(2),mL/kg/min)during PA divided by 2.7 m L/kg/min(MET_(60+))to account for the lower resting metabolic rate in older adults.Results:We identified 68 articles and extracted energy expenditure data on 427 PAs.From these,we derived 99 unique Specific Activity codes with corresponding MET_(60+)values for older adults.We developed a website to present the OA Compendium MET_(60+)values:https://pacompendium.com.Conclusion:The OA Compendium uses data collected from adults>60 years for more accurate estimation of the energy cost of PAs in older adults.It is an accessible resource that will allow researchers,educators,and practitioners to find MET_(60+)values for older adults for use in PA research and practice. 展开更多
关键词 energy expenditure EXERCISE MET Older adults
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Oxygen functionalization-assisted anionic exchange toward unique construction of flower-like transition metal chalcogenide embedded carbon fabric for ultra-long life flexible energy storage and conversion 被引量:1
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作者 Roshan M.Bhattarai Kisan Chhetri +5 位作者 Nghia Le Debendra Acharya Shirjana Saud Mai Cao Hoang Phuong Lan Nguyen Sang Jae Kim Young Sun Mok 《Carbon Energy》 SCIE EI CAS CSCD 2024年第1期72-93,共22页
The metal-organic framework(MOF)derived Ni–Co–C–N composite alloys(NiCCZ)were“embedded”inside the carbon cloth(CC)strands as opposed to the popular idea of growing them upward to realize ultrastable energy storag... The metal-organic framework(MOF)derived Ni–Co–C–N composite alloys(NiCCZ)were“embedded”inside the carbon cloth(CC)strands as opposed to the popular idea of growing them upward to realize ultrastable energy storage and conversion application.The NiCCZ was then oxygen functionalized,facilitating the next step of stoichiometric sulfur anion diffusion during hydrothermal sulfurization,generating a flower-like metal hydroxysulfide structure(NiCCZOS)with strong partial implantation inside CC.Thus obtained NiCCZOS shows an excellent capacity when tested as a supercapacitor electrode in a three-electrode configuration.Moreover,when paired with the biomass-derived nitrogen-rich activated carbon,the asymmetric supercapacitor device shows almost 100%capacity retention even after 45,000 charge–discharge cycles with remarkable energy density(59.4 Wh kg^(-1)/263.8μWh cm^(–2))owing to a uniquely designed cathode.Furthermore,the same electrode performed as an excellent bifunctional water-splitting electrocatalyst with an overpotential of 271 mV for oxygen evolution reaction(OER)and 168.4 mV for hydrogen evolution reaction(HER)at 10 mA cm−2 current density along with 30 h of unhinged chronopotentiometric stability performance for both HER and OER.Hence,a unique metal chalcogenide composite electrode/substrate configuration has been proposed as a highly stable electrode material for flexible energy storage and conversion applications. 展开更多
关键词 carbon cloth energy conversion energy storage FLEXIBLE metal embedding ultra-stable
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RELATIVE ENTROPY DIMENSION FOR COUNTABLE AMENABLE GROUP ACTIONS
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作者 肖祖彪 殷正宇 《Acta Mathematica Scientia》 SCIE CSCD 2023年第6期2430-2448,共19页
We study the topological complexities of relative entropy zero extensions acted upon by countable-infinite amenable groups.First,for a given Følner sequence,we define the relative entropy dimensions and the dimen... We study the topological complexities of relative entropy zero extensions acted upon by countable-infinite amenable groups.First,for a given Følner sequence,we define the relative entropy dimensions and the dimensions of the relative entropy generating sets to characterize the sub-exponential growth of the relative topological complexity.we also investigate the relations among these.Second,we introduce the notion of a relative dimension set.Moreover,using the method,we discuss the disjointness between the relative entropy zero extensions via the relative dimension sets of two extensions,which says that if the relative dimension sets of two extensions are different,then the extensions are disjoint. 展开更多
关键词 amenable groups relative entropy dimensions relative dimension sets
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Understanding the Relationship Between Shrinking Cities and Land Prices:Spatial Pattern,Effectiveness,and Policy Implications 被引量:1
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作者 WANG Xiaohui PENG Li +1 位作者 HUANG Kexin DENG Wei 《Chinese Geographical Science》 SCIE CSCD 2024年第1期1-18,共18页
Urban shrinkage has emerged as a widespread phenomenon globally and has a significant impact on land,particularly in terms of land use and price.This study focuses on 2851 county-level cities in China in 2005–2018(ex... Urban shrinkage has emerged as a widespread phenomenon globally and has a significant impact on land,particularly in terms of land use and price.This study focuses on 2851 county-level cities in China in 2005–2018(excluding Hong Kong,Macao,Taiwan,and‘no data’areas in Qinhai-Tibet Plateau)as the fundamental units of analysis.By employing nighttime light(NTL)data to identify shrinking cities,the propensity score matching(PSM)model was used to quantitatively examine the impact of shrinking cities on land prices,and evaluate the magnitude of this influence.The findings demonstrate the following:1)there were 613 shrinking cities in China,with moderate shrinkage being the most prevalent and severe shrinkage being the least.2)Regional disparities are evident in the spatial distribution of shrinking cities,especially in areas with diverse terrain.3)The spatial pattern of land price exhibits a significant correlated to the economic and administrative levels.4)Shrinking cities significantly negatively impact on the overall land price(ATT=–0.1241,P<0.05).However,the extent of the effect varies significantly among different spatial regions.This study contributes novel insights into the investigation of land prices and shrinking cities,ultimately serving as a foundation for government efforts to promote the sustainable development of urban areas. 展开更多
关键词 shrinking cities land price propensity score matching(PSM) relative effectiveness China
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Relative-Position Estimation Based on Loosely Coupled UWB–IMU Fusion for Wearable IoT Devices
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作者 A.S.M.Sharifuzzaman Sagar Taein Kim +2 位作者 Soyoung Park Hee Seh Lee Hyung Seok Kim 《Computers, Materials & Continua》 SCIE EI 2023年第4期1941-1961,共21页
Relative positioning is one of the important techniques in collaborativerobotics, autonomous vehicles, and virtual/augmented reality (VR/AR)applications. Recently, ultra-wideband (UWB) has been utilized to calculatere... Relative positioning is one of the important techniques in collaborativerobotics, autonomous vehicles, and virtual/augmented reality (VR/AR)applications. Recently, ultra-wideband (UWB) has been utilized to calculaterelative position as it does not require a line of sight compared to a camerato calculate the range between two objects with centimeter-level accuracy.However, the single UWB range measurement cannot provide the relativeposition and attitude of any device in three dimensions (3D) because oflacking bearing information. In this paper, we have proposed a UWB-IMUfusion-based relative position system to provide accurate relative positionand attitude between wearable Internet of Things (IoT) devices in 3D. Weintroduce a distributed Euler angle antenna orientationwhich can be equippedwith the mobile structure to enable relative positioning. Moving average andmin-max removing preprocessing filters are introduced to reduce the standarddeviation. The standard multilateration method is modified to calculate therelative position between mobile structures. We combine UWB and IMUmeasurements in a probabilistic framework that enables users to calculatethe relative position between two nodes with less error. We have carried outdifferent experiments to illustrate the advantages of fusing IMU and UWBranges for relative positioning systems. We have achieved a mean accuracy of0.31m for 3D relative positioning in indoor line of sight conditions. 展开更多
关键词 relative position UWB IMU TRILATERATION IOT bayesian filter
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