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Thermal decomposition and kinetics of diisopropyl methylphosphonate(DIMP),a chemical warfare agent simulant
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作者 Natalie Gese Hergen Eilers 《Defence Technology(防务技术)》 2026年第1期40-51,共12页
Chemical warfare agents(CWAs)remain a persistent hazard in many parts of the world,necessitating a deeper exploration of their chemical and physical characteristics and reactions under diverse conditions.Diisopropyl m... Chemical warfare agents(CWAs)remain a persistent hazard in many parts of the world,necessitating a deeper exploration of their chemical and physical characteristics and reactions under diverse conditions.Diisopropyl methylphosphonate(DIMP),a commonly used CWA surrogate,is widely studied to enhance our understanding of CWA behavior.The prevailing thermal decomposition model for DIMP,developed approximately 25 years ago,is based on data collected in nitrogen atmospheres at temperatures ranging from 700 K to 800 K.Despite its limitations,this model continues to serve as a foundation for research across various thermal and reactive environments,including combustion studies.Our recent experiments have extended the scope of decomposition analysis by examining DIMP in both nitrogen and zero air across a lower temperature range of 175??C to 250??C.Infrared spectroscopy results under nitrogen align well with the established model;however,we observed that catalytic effects,stemming from decomposition byproducts and interactions with stainless steel surfaces,alter the reaction kinetics.In zero air environments,we observed a novel infrared absorption band.Spectral fitting suggests this band may represent a combination of propanal and acetone,while GCMS analysis points to vinyl formate and acetone as possible constituents.Although the precise identity of these new products remains unresolved,our findings clearly indicate that the existing decomposition model cannot be reliably extended to lower temperatures or non-nitrogen environments without further revisions. 展开更多
关键词 Chemical warfare agents Simulants Diisopropyl methylphosphonate Thermal decomposition decomposition model PROPANAL Vinyl formate ACETONE
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Advanced isoconversional kinetic analysis of lepidolite sulfation product decomposition reactions for selectively extracting lithium
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作者 Yubo Liu Baozhong Ma +4 位作者 Jiahui Cheng Xiang Li Hui Yang Chengyan Wang Yongqiang Chen 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期217-227,共11页
The sulfation and decomposition process has proven effective in selectively extracting lithium from lepidolite.It is essential to clarify the thermochemical behavior and kinetic parameters of decomposition reactions.A... The sulfation and decomposition process has proven effective in selectively extracting lithium from lepidolite.It is essential to clarify the thermochemical behavior and kinetic parameters of decomposition reactions.Accordingly,comprehensive kinetic study by employing thermalgravimetric analysis at various heating rates was presented in this paper.Two main weight loss regions were observed during heating.The initial region corresponded to the dehydration of crystal water,whereas the subsequent region with overlapping peaks involved complex decomposition reactions.The overlapping peaks were separated into two individual reaction peaks and the activation energy of each peak was calculated using isoconversional kinetics methods.The activation energy of peak 1 exhibited a continual increase as the reaction conversion progressed,while that of peak 2 steadily decreased.The optimal kinetic models,identified as belonging to the random nucleation and subsequent growth category,provided valuable insights into the mechanism of the decomposition reactions.Furthermore,the adjustment factor was introduced to reconstruct the kinetic mechanism models,and the reconstructed models described the kinetic mechanism model more accurately for the decomposition reactions.This study enhanced the understanding of the thermochemical behavior and kinetic parameters of the lepidolite sulfation product decomposition reactions,further providing theoretical basis for promoting the selective extraction of lithium. 展开更多
关键词 LITHIUM LEPIDOLITE decomposition reactions KINETICS isoconversional analysis
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Unanticipated strengthening of Cu−19Ni−6Cr−7Mn alloy achieved by synergistic effect of spinodal decomposition and multiscale precipitation
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作者 Shao-lin LI Ying-ying ZHU +3 位作者 Xiu-hua GUO Qiang-song WANG Wen-ming SUN Ke-xing SONG 《Transactions of Nonferrous Metals Society of China》 2026年第1期183-202,共20页
The microstructural evolution of Cu−19Ni−6Cr−7Mn alloy during aging treatment was investigated.After aging for 120 min at 500℃,the alloy exhibited excellent mechanical properties,including a tensile strength of 978 M... The microstructural evolution of Cu−19Ni−6Cr−7Mn alloy during aging treatment was investigated.After aging for 120 min at 500℃,the alloy exhibited excellent mechanical properties,including a tensile strength of 978 MPa and an elastic modulus of 145.8 GPa.After aging for 240 min at 500℃,the elastic modulus of the alloy reached 149.5 GPa,which was among the highest values reported for Cu alloys.It was worth mentioning that the tensile strength increased rapidly from 740 to 934 MPa after aging for 5 min at 500℃,which was close to the maximum tensile strength(978 MPa).Analysis of the underlying strengthening mechanisms and phase transformation behavior revealed that the Cu−19Ni−6Cr−7Mn alloy underwent spinodal decomposition and DO_(22) ordering during the first 5 min of aging at 500℃,and L1_(2) ordered phases and bcc-Cr precipitates appeared.Therefore,the enhanced mechanical properties of the Cu−19Ni−6Cr−7Mn alloy can be attributed to the stress field generated by spinodal decomposition and the presence of nanoscale ordered phase and Cr precipitates. 展开更多
关键词 Cu−Ni−Cr−Mn alloy mechanical properties nanoscale precipitates spinodal decomposition elastic modulus
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A bifunctional cathode enabling efficient decomposition and utilization of nitrous oxide in protonic ceramic fuel cells for power generation
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作者 Tao Yuan Shaozhuo Jia +7 位作者 Chen Song Yutao Rong Cong Ren Zhimin Li Yubin Chen Youjun Lu Weiwei Wu Yihang Li 《Nano Research》 2026年第1期598-609,共12页
Protonic ceramic fuel cells(PCFCs)have been recognized as promising power generation devices for future clean energy systems,owing to their relatively low activation energy for proton migration and high energy convers... Protonic ceramic fuel cells(PCFCs)have been recognized as promising power generation devices for future clean energy systems,owing to their relatively low activation energy for proton migration and high energy conversion efficiency.In certain application scenarios,the use of N_(2)O(a potent greenhouse gas),as an alternative oxidant to air,presents a feasible strategy.Herein,we report for the first time the operation of PCFCs employing N_(2)O as the oxidant.A hybrid Pr_(2)Ni_(0.6)Co_(0.4)O_(4-δ)(PNCO-214)catalyst is developed,comprising Ruddlesden-Popper(R-P)structured Pr_(4)Ni_(1.8)Co_(1.2)O_(10-δ)(PNCO-4310)and fluorite structured Pr_(6)O_(11)(PO-611),which synergistically exhibits exceptional catalytic activity toward both N_(2)O decomposition and the oxygen reduction reaction,achieving a conversion over 92% and an area specific resistance of 1.301Ω·cm^(2) at 600℃.Quasi-insitu temperature-dependent Fourier transform infrared(FTIR)and electrochemical impedance spectroscopy analyses reveal that abundant oxygen vacancies in PNCO-214 facilitate rapid adsorption and dissociation of N_(2)O into N_(2) and O_(2),while also promoting the surface exchange kinetics of proton/oxygen during oxygen reduction reaction(ORR).When applied in an anode-supported single cell with PNCO-214 cathode operating under N_(2)O,outstanding power density and low resistance are achieved,delivering 0.801 W·cm^(-2) and 0.245Ω·cm^(2) at 600℃.Satisfactory performance is also maintained even when the temperature is reduced to 500℃.Furthermore,the single cell demonstrates relatively good stability with negligible degradation over 130 h at 600℃ and 0.7 V.These findings underscore the potential of PNCO-214 as a highly effective cathode catalyst for enabling the use of N_(2)O as a viable oxidant in PCFCs for specific industrial applications. 展开更多
关键词 protonic ceramic fuel cells hybrid catalyst N_(2)O decomposition oxygen reduction reaction quasi-in-situ characterization
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SPECIAL ISSUE: INCOME INEQUALITY IN CHINA Inter-industry Inequality: An Important Source of the Urban Income Gap--Regression-based Decomposition 被引量:4
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作者 Chen Zhao Wan Guanghua Lu Ming 《Social Sciences in China》 2011年第2期159-177,共19页
Regression-based decomposition of inter-industry earnings differentials shows that in 1988, 1995 and 2002, inter-industry earnings differentials made an increasing contribution to urban earnings inequality in China. T... Regression-based decomposition of inter-industry earnings differentials shows that in 1988, 1995 and 2002, inter-industry earnings differentials made an increasing contribution to urban earnings inequality in China. The primary reason for the widening gap lay in monopoly industries. At the same time, geographical location, educational level, type of enterprise ownership, type of occupation and whether the individual had a second job also contributed to rising earnings inequality, while age and being fully employed made a decreasing contribution. Therefore, if China is to reduce the earnings gap it is imperative that we remove barriers to labor market entry and break down some monopoly industries in the product market. Additionally, reducing obstacles to the free movement of labor and improving workers' educational level should also be important elements of the government's strategy for reducing the urban income gap in future. 展开更多
关键词 monopoly industries decomposition of income differentials Shapley value
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Coastal ozone dynamics and formation regime in Eastern China:Integrating trend decomposition and machine learning techniques 被引量:1
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作者 Lei Tong Zhuoliang Gu +8 位作者 Xuchu Zhu Cenyan Huang Baoye Hu Yasheng Shi Yang Meng Jie Zheng Mengmeng He Jun He Hang Xiao 《Journal of Environmental Sciences》 2025年第9期597-612,共16页
Machine-learning is a robust technique for understanding pollution characteristics of surface ozone,which are at high levels in urban China.This study introduced an innovative approach combining trend decomposition wi... Machine-learning is a robust technique for understanding pollution characteristics of surface ozone,which are at high levels in urban China.This study introduced an innovative approach combining trend decomposition with Random Forest algorithm to investigate ozone dynamics and formation regimes in a coastal area of China.During the period of 2017–2022,significant inter-annual fluctuations emerged,with peaks in mid-2017 attributed to volatile organic compounds(VOCs),and in late-2019 influenced by air temperature.Multifaceted periodicities(daily,weekly,holiday,and yearly)in ozone were revealed,elucidating substantial influences of daily and yearly components on ozone periodicity.A VOC-sensitive ozone formation regime was identified,characterized by lower VOCs/NO_(x) ratios(average=0.88)and significant positive correlations between ozone and VOCs.This interplay manifested in elevated ozone duringweekends,holidays,and pandemic lockdowns.Key variables influencing ozone across diverse timescaleswere uncovered,with solar radiation and temperature driving daily and yearly ozone variations,respectively.Precursor substances,particularly VOCs,significantly shaped weekly/holiday patterns and long-term trends of ozone.Specifically,acetone,ethane,hexanal,and toluene had a notable impact on the multi-year ozone trend,emphasizing the urgency of VOC regulation.Furthermore,our observations indicated that NO_(x) primarily drived the stochastic variations in ozone,a distinguishing characteristic of regions with heavy traffic.This research provides novel insights into ozone dynamics in coastal urban areas and highlights the importance of integrating statistical and machinelearning methods in atmospheric pollution studies,with implications for targeted mitigation strategies beyond this specific region and pollutant. 展开更多
关键词 Time series decomposition Random forest VOC-sensitive Long-term trend Port area
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DecMamba:Mamba Utilizing Series Decomposition for Multivariate Time Series Forecasting
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作者 Jianxin Feng Jianhao Zhang +2 位作者 Ge Cao Zhiguo Liu Yuanming Ding 《Computers, Materials & Continua》 SCIE EI 2025年第1期1049-1068,共20页
Multivariate time series forecasting iswidely used in traffic planning,weather forecasting,and energy consumption.Series decomposition algorithms can help models better understand the underlying patterns of the origin... Multivariate time series forecasting iswidely used in traffic planning,weather forecasting,and energy consumption.Series decomposition algorithms can help models better understand the underlying patterns of the original series to improve the forecasting accuracy of multivariate time series.However,the decomposition kernel of previous decomposition-based models is fixed,and these models have not considered the differences in frequency fluctuations between components.These problems make it difficult to analyze the intricate temporal variations of real-world time series.In this paper,we propose a series decomposition-based Mamba model,DecMamba,to obtain the intricate temporal dependencies and the dependencies among different variables of multivariate time series.A variable-level adaptive kernel combination search module is designed to interact with information on different trends and periods between variables.Two backbone structures are proposed to emphasize the differences in frequency fluctuations of seasonal and trend components.Mamba with superior performance is used instead of a Transformer in backbone structures to capture the dependencies among different variables.A new embedding block is designed to capture the temporal features better,especially for the high-frequency seasonal component whose semantic information is difficult to acquire.A gating mechanism is introduced to the decoder in the seasonal backbone to improve the prediction accuracy.A comparison with ten state-of-the-art models on seven real-world datasets demonstrates that DecMamba can better model the temporal dependencies and the dependencies among different variables,guaranteeing better prediction performance for multivariate time series. 展开更多
关键词 Data prediction time series Mamba series decomposition
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Attenuating reductive decomposition of fiuorinated electrolytes for high-voltage lithium metal batteries 被引量:1
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作者 Zhen-Zhen Dong Jin-Hao Zhang +4 位作者 Lin Zhu Xiao-Zhong Fan Zhen-Guo Liu Yi-Bo Yan Long Kong 《Chinese Chemical Letters》 2025年第4期416-419,共4页
Fluoride-based electrolyte exhibits extraordinarily high oxidative stability in high-voltage lithium metal batteries(h-LMBs) due to the inherent low highest occupied molecular orbital(HOMO) of fiuorinated solvents. Ho... Fluoride-based electrolyte exhibits extraordinarily high oxidative stability in high-voltage lithium metal batteries(h-LMBs) due to the inherent low highest occupied molecular orbital(HOMO) of fiuorinated solvents. However, such fascinating properties do not bring long-term cyclability of h-LMBs. One of critical challenges is the interface instability in contacting with the Li metal anode, as fiuorinated solvents are highly susceptible to exceptionally reductive metallic Li attributed to its low lowest unoccupied molecular orbital(LUMO), which leads to significant consumption of the fiuorinated components upon cycling.Herein, attenuating reductive decomposition of fiuorinated electrolytes is proposed to circumvent rapid electrolyte consumption. Specifically, the vinylene carbonate(VC) is selected to tame the reduction decomposition by preferentially forming protective layer on the Li anode. This work, experimentally and computationally, demonstrates the importance of pre-passivation of Li metal anodes at high voltage to attenuate the decomposition of fiuoroethylene carbonate(FEC). It is expected to enrich the understanding of how VC attenuate the reactivity of FEC, thereby extending the cycle life of fiuorinated electrolytes in high-voltage Li-metal batteries. 展开更多
关键词 Li metal batteries Solid electrolyte interphase High voltage Fluorinated electrolyte Electrolyte decomposition
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A Multi-Objective Particle Swarm Optimization Algorithm Based on Decomposition and Multi-Selection Strategy
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作者 Li Ma Cai Dai +1 位作者 Xingsi Xue Cheng Peng 《Computers, Materials & Continua》 SCIE EI 2025年第1期997-1026,共30页
The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization problems.In the article,amulti-objective particle swarm optimization algorithmbased on decomposition... The multi-objective particle swarm optimization algorithm(MOPSO)is widely used to solve multi-objective optimization problems.In the article,amulti-objective particle swarm optimization algorithmbased on decomposition and multi-selection strategy is proposed to improve the search efficiency.First,two update strategies based on decomposition are used to update the evolving population and external archive,respectively.Second,a multiselection strategy is designed.The first strategy is for the subspace without a non-dominated solution.Among the neighbor particles,the particle with the smallest penalty-based boundary intersection value is selected as the global optimal solution and the particle far away fromthe search particle and the global optimal solution is selected as the personal optimal solution to enhance global search.The second strategy is for the subspace with a non-dominated solution.In the neighbor particles,two particles are randomly selected,one as the global optimal solution and the other as the personal optimal solution,to enhance local search.The third strategy is for Pareto optimal front(PF)discontinuity,which is identified by the cumulative number of iterations of the subspace without non-dominated solutions.In the subsequent iteration,a new probability distribution is used to select from the remaining subspaces to search.Third,an adaptive inertia weight update strategy based on the dominated degree is designed to further improve the search efficiency.Finally,the proposed algorithmis compared with fivemulti-objective particle swarm optimization algorithms and five multi-objective evolutionary algorithms on 22 test problems.The results show that the proposed algorithm has better performance. 展开更多
关键词 Multi-objective optimization multi-objective particle swarm optimization decomposition multi-selection strategy
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A C_(6)-decomposition of theλ-fold Line Graph of K_(x,y)
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作者 XIN Yue YANG Weihua 《数学进展》 北大核心 2025年第6期1205-1222,共18页
In this paper,we prove that L(K_(x,y))(λ),theλ-fold line graph of the complete bipartite graph Ka,y,has a C_(6)-decomposition if and only if ry≥6,λxy(c+y-2)=0(mod 12)and(x+y)=0(mod 2),where x,y are nonnegative int... In this paper,we prove that L(K_(x,y))(λ),theλ-fold line graph of the complete bipartite graph Ka,y,has a C_(6)-decomposition if and only if ry≥6,λxy(c+y-2)=0(mod 12)and(x+y)=0(mod 2),where x,y are nonnegative integers and(x,y)≠(2,4)or(2,5). 展开更多
关键词 cycle decomposition line graph complete bipartite graph
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Research on Denoising Method of Agricultural Product Terahertz Spectroscopy Based on Adaptive Signal Decomposition
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作者 WU Jing-zhu LIU Yu-hao +3 位作者 YANG Yi XIE Chuan-luan L Zhong-ming LI Yi-can 《光谱学与光谱分析》 北大核心 2025年第12期3575-3584,共10页
To address the issues of peak overlap caused by complex matrices in agricultural product terahertz(THz)spectral signals and the dynamic,nonlinear interference induced by environmental and system noise,this study explo... To address the issues of peak overlap caused by complex matrices in agricultural product terahertz(THz)spectral signals and the dynamic,nonlinear interference induced by environmental and system noise,this study explores the feasibility of adaptive-signal-decomposition-based denoising methods to improve THz spectral quality.THz time-domain spectroscopy(THz-TDS)combined with an attenuated total reflection(ATR)accessory was used to collect THz absorbance spectra from 48 peanut samples.Taking the quantitative prediction model of peanut moisture content based on THz-ATR as an example,wavelet transform(WT),empirical mode decomposition(EMD),local mean decomposition(LMD),and its improved methods-segmented local mean decomposition(SLMD)and piecewise mirror extension local mean decomposition(PME-LMD)-were employed for spectral denoising.The applicability of different denoising methods was evaluated using a support vector regression(SVR)model.Experimental results show that the peanut moisture content prediction model constructed after PME-LMD denoising achieved the best performance,with a root mean square error(RMSE),coefficient of determination(R^(2)),and mean absolute percentage error(MAPE)of 0.010,0.912,and 0.040,respectively.Compared with traditional methods,PME-LMD significantly improved spectral quality and model prediction performance.The PME-LMD denoising strategy proposed in this study effectively suppresses non-uniform noise interference in THz spectral signals,providing an efficient and accurate preprocessing method for THz spectral analysis of agricultural products.This research provides theoretical support and technical guidance for the application of THz technology for detecting agricultural product quality. 展开更多
关键词 Terahertz spectroscopy Denoising method Agricultural products Support vector regression Piecewise mirror extension local mean decomposition
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Field experiment and simulation for catalytic decomposition of ozone by exterior wall coatings with self-purifying materials
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作者 Lei Zhang Jingwen Cui +7 位作者 Delai Wang Yunfeng Li Yafei Wang Xue Han Shuyang Xie Junfeng Liu Jinzhu Ma Haixin Guo 《Journal of Environmental Sciences》 2025年第8期847-858,共12页
In recent years,ozone has become one of the key pollutants affecting the urban air qual-ity.Direct catalytic decomposition of ozone emerges as an effective method for ozone re-moval.Field experimentswere conducted to ... In recent years,ozone has become one of the key pollutants affecting the urban air qual-ity.Direct catalytic decomposition of ozone emerges as an effective method for ozone re-moval.Field experimentswere conducted to evaluate the effectiveness of exteriorwall coat-ings with ozone decomposition catalysts for ozone removal in practical applications.ANSYS 2020R1 software was first used for simulation and analysis of ozone concentration and flow fields to investigate the decomposition boundary of these wall coatings.The results show that the exterior wall coatings with manganese-based catalysts can effectively reduce the ozone concentration near the wall coating.The ozone decomposition efficiency is nega-tively correlated with the distance fromthe coating and the decomposition boundary range is around 18 m.The decomposition boundary will increase with the increase of tempera-ture,and decrease with the increase of the wind speed and the relative humidity.These results underscore the viability of using exterior wall coatings with catalysts for controlling ozone pollution in atmospheric environments.This approach presents a promising avenue for addressing ozone pollution through self-purifying materials on building external wall. 展开更多
关键词 Exterior wall coating Self-purifying materials OZONE Catalytic decomposition decomposition boundary
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Multi-component decompositions,linear superpositions,and new nonlinear integrable coupled KdV-type systems
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作者 Xiazhi Hao S Y Lou 《Communications in Theoretical Physics》 2025年第2期1-12,共12页
In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrabilit... In the realm of nonlinear integrable systems,the presence of decompositions facilitates the establishment of linear superposition solutions and the derivation of novel coupled systems exhibiting nonlinear integrability.By focusing on single-component decompositions within the potential BKP hierarchy,it has been observed that specific linear superpositions of decomposition solutions remain consistent with the underlying equations.Moreover,through the implementation of multi-component decompositions within the potential BKP hierarchy,successful endeavors have been undertaken to formulate linear superposition solutions and novel coupled Kd V-type systems that resist decoupling via alterations in dependent variables. 展开更多
关键词 integrable system single-component decomposition multi-component decomposition linear superposition integrable coupled KdV-type system
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Direct Decomposition of NO over Cobalt-based Perovskite Catalyst La_(1-x)K_(x)CoO_(3)(x=0.1-0.4)under Microwave Irradiation
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作者 WANG Hao ZHOU Shijia +2 位作者 WANG Qiulong ZHAO Shuohan DU Jingxin 《Journal of Wuhan University of Technology(Materials Science)》 2025年第2期353-358,共6页
We presented the preparation and analysis of La_(1-x)K_(x)CoO_(3)(x=0.1-0.4)catalysts,supported on microwave-absorbing ceramic carriers,using the sol-gel method.We systematically investigated the effects of various re... We presented the preparation and analysis of La_(1-x)K_(x)CoO_(3)(x=0.1-0.4)catalysts,supported on microwave-absorbing ceramic carriers,using the sol-gel method.We systematically investigated the effects of various reaction conditions under microwave irradiation(0-50 W).These conditions included reaction temperatures(300-600℃),oxygen concentrations(0-6%),and varying K^(+)doping levels on the catalysts'activity.The crystalline phase,microstructure,and the catalytic activity of the catalyst were analyzed by XRD,TEM,H_2-TPR,and O_(2)-TPD.The experimental results reveal that La_(1-x)K_(x)CoO_(3)(x=0.1-0.4)catalysts consistently form homogeneous perovskite nanoparticles across different doping levels.The NO decomposition efficiency on these catalysts initially increases and then decreases with variations in doping amount,temperature,and microwave power.Additionally,an increase in oxygen concentration positively influences NO conversion rates.The optimal performance is observed with La_(0.7)K_(0.3)CoO_(3)catalyst under conditions of x=0.3,400℃,10 W microwave power,and 4%oxygen concentration,achieving a peak NO conversion rate of La_(0.7)K_(0.3)CoO_(3)catalyst is 93.1%. 展开更多
关键词 microwave catalysis direct decomposition of NO perovskite catalyst
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A new insight into the straw decomposition associated with minerals:Promoting straw humification and Cd immobilization
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作者 Yuling Liu Haowei Zeng +3 位作者 Siduo Ding Zhong Hu Baiqing Tie Si Luo 《Journal of Environmental Sciences》 2025年第2期553-566,共14页
Organic matter(OM)derived from the decomposition of crop residues plays a key role as a sorbent for cadmium(Cd)immobilization.Few studies have explored the straw decomposition processes with the presence of minerals,a... Organic matter(OM)derived from the decomposition of crop residues plays a key role as a sorbent for cadmium(Cd)immobilization.Few studies have explored the straw decomposition processes with the presence of minerals,and the effect of newly generated organomineral complexes on heavy metal adsorption.In this study,we investigated the variations in structure and composition during the rice straw decomposition with or without minerals(goethite and kaolinite),as well as the adsorption behavior and mechanisms by which straw decomposition affects Cd immobilization.The degree of humification of extracted straw organic matter was assessed using excitation-emission matrix(EEM)fluorescence and Ultraviolet-visible spectroscopy(UV-vis),while employing FTIR spectroscopy and XPS to characterize the adsorption mechanisms.The spectra analysis revealed the enrichment of highly aromatic and hydrophobic components,indicating that the degree of straw decomposition and humification were further intensified during incubation.Additionally,the existence of goethite(SG)accelerated the humification of OM.Sorption experiments revealed that the straw humification increased Cd adsorption capacity.Notably,SG exhibited significantly higher adsorption performance compared to the organic matter without minerals(RS)and the existence of kaolinite(SK).Further analysis using FT-IR spectroscopy and XPS verified that the primarymechanisms involved in Cd immobilization were complexion with—OH and—COOH,as well as the formation of Cd-πbinds with aromatic C=C on the surface of solid OMs.These findings will facilitate understanding the interactions of the rice straw decomposing with soil minerals and its remediation effect on Cd-contaminated farmland. 展开更多
关键词 Organic matter Cadmium(Cd) decomposition MINERALS Adsorption
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Stoichiometric change and solid decomposition in Ca–S compounds under high pressure
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作者 Yang Lv Jian-Fu Li +4 位作者 Zhao-Bin Zhang Yong Liu Jia-Nan Yuan Jia-Ni Lin Xiao-Li Wang 《Chinese Physics B》 2025年第4期92-100,共9页
As an independent thermodynamic parameter,pressure significantly influences interatomic distances,leading to an increase in material density.In this work,we employ the CALYPSO structure search and density functional t... As an independent thermodynamic parameter,pressure significantly influences interatomic distances,leading to an increase in material density.In this work,we employ the CALYPSO structure search and density functional theory calculations to explore the structural phase transitions and electronic properties of calcium-sulfur compounds(Ca_(x)S_(1-x),where x=1/4,1/3,1/2,2/3,3/4,4/5)under 0-1200 GPa.The calculated formation enthalpies suggest that Ca_(x)S_(1-x)compounds undergo multiple phase transitions and eventually decompose into elemental Ca and S,challenging the traditional view that pressure stabilizes and densifies compounds.The analysis of formation enthalpy indicates that an increase in pressure leads to a rise in internal energy and the PV term,resulting in thermodynamic instability.Bader charge analysis reveals that this phenomenon is attributed to a decrease in charge transfer under high pressure.The activation of Ca-3d orbitals is significantly enhanced under pressure,leading to competition with Ca-4s orbitals and S-3p orbitals.This may cause the formation enthalpy minimum on the convex hull to shift sequentially from CaS to CaS_(3),then to Ca_(3)S and Ca_(2)S,and finally back to CaS.These findings provide critical insights into the behavior of alkaline-earth metal sulfides under high pressure,with implications for the synthesis and application of novel materials under extreme conditions and for understanding element distribution in planetary interiors. 展开更多
关键词 high pressure calcium sulfide STOICHIOMETRY solid decomposition
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Detecting seismic precursors in groundwater fluctuations using masking empirical mode decomposition and modified zerocrossing techniques
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作者 Hak Soo Hwang Sul-Min Yun +2 位作者 Do Yeon Hwang Kyoochul Ha Se-Yeong Hamm 《Episodes》 2025年第4期451-462,共12页
Earthquakes can cause significant hazards,leading to loss of human life and property damage.In this study,we applied the masking empirical mode decomposition(EMD)to the Gyeongju earthquake(ML 5.8)in South Korea and th... Earthquakes can cause significant hazards,leading to loss of human life and property damage.In this study,we applied the masking empirical mode decomposition(EMD)to the Gyeongju earthquake(ML 5.8)in South Korea and the Abe Pura earthquake(ML 7.0)in Indonesia and then revealed that the 7th intrinsic mode function(IMF7),composed of waveforms with a period band of approximately 150 to 750 minutes. 展开更多
关键词 masking empirical mode decomposition masking empirical mode decomposition emd modified zerocrossing techniques th intrinsic mode function imf composed EARTHQUAKES seismic precursors groundwater fluctuations
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Decomposition for Large-Scale Optimization Problems:An Overview
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作者 Thai Doan CHUONG Chen LIU Xinghuo YU 《Artificial Intelligence Science and Engineering》 2025年第3期157-174,共18页
Formalizing complex processes and phenomena of a real-world problem may require a large number of variables and constraints,resulting in what is termed a large-scale optimization problem.Nowadays,such large-scale opti... Formalizing complex processes and phenomena of a real-world problem may require a large number of variables and constraints,resulting in what is termed a large-scale optimization problem.Nowadays,such large-scale optimization problems are solved using computing machines,leading to an enormous computational time being required,which may delay deriving timely solutions.Decomposition methods,which partition a large-scale optimization problem into lower-dimensional subproblems,represent a key approach to addressing time-efficiency issues.There has been significant progress in both applied mathematics and emerging artificial intelligence approaches on this front.This work aims at providing an overview of the decomposition methods from both the mathematics and computer science points of view.We also remark on the state-of-the-art developments and recent applications of the decomposition methods,and discuss the future research and development perspectives. 展开更多
关键词 decomposition methods nonlinear optimization large-scale problems computational intelligence
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Topology-aware tensor decomposition for meta-graph learning
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作者 Hansi Yang Quanming Yao 《CAAI Transactions on Intelligence Technology》 2025年第3期891-901,共11页
Heterogeneous graphs generally refer to graphs with different types of nodes and edges.A common approach for extracting useful information from heterogeneous graphs is to use meta-graphs,which can be seen as a special... Heterogeneous graphs generally refer to graphs with different types of nodes and edges.A common approach for extracting useful information from heterogeneous graphs is to use meta-graphs,which can be seen as a special kind of directed acyclic graph with same node and edge types as the heterogeneous graph.However,how to design proper metagraphs is challenging.Recently,there have been many works on learning suitable metagraphs from a heterogeneous graph.Existing methods generally introduce continuous weights for edges that are independent of each other,which ignores the topological structures of meta-graphs and can be ineffective.To address this issue,the authors propose a new viewpoint from tensor on learning meta-graphs.Such a viewpoint not only helps interpret the limitation of existing works by CANDECOMP/PARAFAC(CP)decomposition,but also inspires us to propose a topology-aware tensor decomposition,called TENSUS,that reflects the structure of DAGs.The proposed topology-aware tensor decomposition is easy to use and simple to implement,and it can be taken as a plug-in part to upgrade many existing works,including node classification and recommendation on heterogeneous graphs.Experimental results on different tasks demonstrate that the proposed method can significantly improve the state-of-the-arts for all these tasks. 展开更多
关键词 graph neural network heterogeneous graph polymorphic network tensor decomposition
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Tensor decomposition reveals trans-regulated gene modules in maize drought response
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作者 Jiawen Lu Yuxin Xie +2 位作者 Chunhui Li Jinliang Yang Junjie Fu 《Journal of Genetics and Genomics》 2025年第6期786-798,共13页
When plants respond to drought stress,dynamic cellular changes occur,accompanied by alterations in gene expression,which often act through trans-regulation.However,the detection of trans-acting genetic variants and ne... When plants respond to drought stress,dynamic cellular changes occur,accompanied by alterations in gene expression,which often act through trans-regulation.However,the detection of trans-acting genetic variants and networks of genes is challenged by the large number of genes and markers.Using a tensor decomposition method,we identify trans-acting expression quantitative trait loci(trans-eQTLs)linked to gene modules,rather than individual genes,which were associated with maize drought response.Module-to-trait association analysis demonstrates that half of the modules are relevant to drought-related traits.Genome-wide association studies of the expression patterns of each module identify 286 trans-eQTLs linked to drought-responsive modules,the majority of which cannot be detected based on individual gene expression.Notably,the trans-eQTLs located in the regions selected during maize improvement tend towards relatively strong selection.We further prioritize the genes that affect the transcriptional regulation of multiple genes in trans,as exemplified by two transcription factor genes.Our analyses highlight that multidimensional reduction could facilitate the identification of trans-acting variations in gene expression in response to dynamic environments and serve as a promising technique for high-order data processing in future crop breeding. 展开更多
关键词 MAIZE Drought stress Tensor decomposition Gene expression trans-eQTL
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