(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]是新型含能钙钛矿化合物的典型代表,需明确其热分解行为、热分解机制及感度特性,以推动其在配方中的应用。以差示扫描量热-热重分析方法实现了分解放热量、分解温度等参数的获取;以动力学模拟计算...(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]是新型含能钙钛矿化合物的典型代表,需明确其热分解行为、热分解机制及感度特性,以推动其在配方中的应用。以差示扫描量热-热重分析方法实现了分解放热量、分解温度等参数的获取;以动力学模拟计算解析了相关分解机理;以同步热分析-红外-质谱联用技术结合原位红外技术探索了(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]的分解产物及分解历程;以国军标法获得了热感度、摩擦感度与撞击感度参数。结果表明:在10℃·min^(-1)的升温速率下,(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]分解放热量为4227 J·g^(-1),分解温度则达到345℃,高于黑索今(RDX)、奥克托今(HMX)、六硝基六氮杂异伍兹烷(CL-20)等多数现役含能材料,显示了优异的热稳定性;分解产物研究表明其立方笼状骨架有效稳定了内部结合的有机物分子,使其热稳定性较高。此外,(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]在100℃下加热48 h的放气量约0.04 m L·g^(-1),撞击感度与机械感度分别为32%和80%,优于RDX和HMX。展开更多
Single-atomic site catalysts have drawn considerable attention because of their maximum atom-utilization efficiency and excellent catalytic activity.In this work,a highly active single-atomic Pt site photocatalyst was...Single-atomic site catalysts have drawn considerable attention because of their maximum atom-utilization efficiency and excellent catalytic activity.In this work,a highly active single-atomic Pt site photocatalyst was synthesized through employing defective Ti0_(2) nanosheets as solid support for photo-catalytic water splitting.It indicated that the surface oxygen vacancies on defective Ti0_(2) nanosheets could effectively stabilize the single-atomic Pt sites through constructing a three-center Ti-Pt-Ti structure.The Ti-Pt-Ti structure can hold the stability of isolated single-atomic Pt sites and facilitate the separation and transfer of photoinduced charge carriers,thereby greatly improving the photocatalytic H2 evolution.Notably,our synthesized photocatalyst exhibited a remarkably enhanced H2 evolution performance,and the H2 production rate is up to 13460.7μmol h^(-1)·g^(-1),which is up to around 29.0 and 4.7 times higher than those of Ti0_(2) nanosheets and Pt nanoparticles-Ti0_(2).In addition,a plausible enhanced reaction mechanism was also proposed combining with photo-electrochemical characterizations and density functional theoiy(DFT)calculation results.Ultimately,it is believed that this work highlights the benefits of a single-site catalyst and paves the way to rationally design the highly active and stable single-atomic site photocatalysts on metal oxide support.展开更多
Structural properties of the organic-inorganic hybrid(C_(2)H_(5)NH_(3))_(2)CuCl_(4) have been investigated by means of x-ray powder diffraction and Rietveld analysis. A structural phase transition from Pbca to Aba2 oc...Structural properties of the organic-inorganic hybrid(C_(2)H_(5)NH_(3))_(2)CuCl_(4) have been investigated by means of x-ray powder diffraction and Rietveld analysis. A structural phase transition from Pbca to Aba2 occurs at T_(4)= 240 K, which results in a paraelectric–ferroelectric phase transition. The release of the Jahn–Teller distortion with increasing temperature toward T_(4) is revealed by the structural analysis.展开更多
As the major source of air pollution,sulfur dioxide(S0_(2))emissions have become the focus of global attention.However,existing studies rarely consider spatial effects when discussing the relationship between foreign ...As the major source of air pollution,sulfur dioxide(S0_(2))emissions have become the focus of global attention.However,existing studies rarely consider spatial effects when discussing the relationship between foreign direct investment(FDI)and S0_(2) emissions.This study took the Yangtze River Delta as the research area and used the spatial panel data of 26 cities in this region for 2004-2017.The study investigated the spatial agglomeration effects and dynamics at work in FDI and S0_(2) emissions by using global and local measures of spatial autocorrelation.Then,based on regression analysis using a results of traditional ordinary least squares(OLS)model and a spatial econometric model,the spatial Durbin model(SDM)with spatial-time effects was adopted to quantify the impact of FDI on S0_(2) emissions,so as to avoid the regression results bias caused by ignoring the spatial effects.The results revealed a significant spatial autocorrelation between FDI and S0_(2) emissions,both of which displayed obvious path dependence characteristics in their geographical distribution.A series of agglomeration regions were observed on the spatial scale.The estimation results of the SDM showed that FDI inflow promoted S0_(2) emissions,which supports the pollution haven hypothesis.The findings of this study are significant in the prevention and control of air pollution in the Yangtze River Delta.展开更多
The non-isothermal decomposition reaction of Nd[(C_5H_ 10NS_2)_3(C_ 12H_8N_2)] were carried out by means of TG-DTG and the thermal decomposition mechanism, and the associated kinetics was investigated. The kinetic par...The non-isothermal decomposition reaction of Nd[(C_5H_ 10NS_2)_3(C_ 12H_8N_2)] were carried out by means of TG-DTG and the thermal decomposition mechanism, and the associated kinetics was investigated. The kinetic parameters are obtained from an analysis of the TG-DTG curves at different heating rate by integral and differential methods. The most probable kinetic model function of the decomposition reaction is Maple Power of n=3/2, f(α)=2/3α -1/2 and the apparent activation energy E is 116.67 kJ·mol -1 and the pre-exponential factor lg[A/s -1] is 7.6891.展开更多
文摘(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]是新型含能钙钛矿化合物的典型代表,需明确其热分解行为、热分解机制及感度特性,以推动其在配方中的应用。以差示扫描量热-热重分析方法实现了分解放热量、分解温度等参数的获取;以动力学模拟计算解析了相关分解机理;以同步热分析-红外-质谱联用技术结合原位红外技术探索了(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]的分解产物及分解历程;以国军标法获得了热感度、摩擦感度与撞击感度参数。结果表明:在10℃·min^(-1)的升温速率下,(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]分解放热量为4227 J·g^(-1),分解温度则达到345℃,高于黑索今(RDX)、奥克托今(HMX)、六硝基六氮杂异伍兹烷(CL-20)等多数现役含能材料,显示了优异的热稳定性;分解产物研究表明其立方笼状骨架有效稳定了内部结合的有机物分子,使其热稳定性较高。此外,(C_(6)H_(14)N_(2))[Na(ClO_(4))_(3)]在100℃下加热48 h的放气量约0.04 m L·g^(-1),撞击感度与机械感度分别为32%和80%,优于RDX和HMX。
基金This research was funded by the Canadian Centre for Clean Coal/Carbon and Mineral Processing Technologies(C5MPT),the National Key R&D Program of China(2017YFB0310803)and the China Scholarship Council(CSC).We thank the NanoFAB at the University of Alberta for the convenience of instruments use,and the kindly help of Nanqi Duan and Chao Qi on sample characterization.
文摘Single-atomic site catalysts have drawn considerable attention because of their maximum atom-utilization efficiency and excellent catalytic activity.In this work,a highly active single-atomic Pt site photocatalyst was synthesized through employing defective Ti0_(2) nanosheets as solid support for photo-catalytic water splitting.It indicated that the surface oxygen vacancies on defective Ti0_(2) nanosheets could effectively stabilize the single-atomic Pt sites through constructing a three-center Ti-Pt-Ti structure.The Ti-Pt-Ti structure can hold the stability of isolated single-atomic Pt sites and facilitate the separation and transfer of photoinduced charge carriers,thereby greatly improving the photocatalytic H2 evolution.Notably,our synthesized photocatalyst exhibited a remarkably enhanced H2 evolution performance,and the H2 production rate is up to 13460.7μmol h^(-1)·g^(-1),which is up to around 29.0 and 4.7 times higher than those of Ti0_(2) nanosheets and Pt nanoparticles-Ti0_(2).In addition,a plausible enhanced reaction mechanism was also proposed combining with photo-electrochemical characterizations and density functional theoiy(DFT)calculation results.Ultimately,it is believed that this work highlights the benefits of a single-site catalyst and paves the way to rationally design the highly active and stable single-atomic site photocatalysts on metal oxide support.
基金supported by the National Natural Science Foundation of China (Grant No. 51925605)Fujian Institute of Innovation,Chinese Academy of Sciences(Grant No. FJCXY18040303)the Youth Innovation Promotion of the Chinese Academy of Sciences (Grant No. 2013004)。
文摘Structural properties of the organic-inorganic hybrid(C_(2)H_(5)NH_(3))_(2)CuCl_(4) have been investigated by means of x-ray powder diffraction and Rietveld analysis. A structural phase transition from Pbca to Aba2 occurs at T_(4)= 240 K, which results in a paraelectric–ferroelectric phase transition. The release of the Jahn–Teller distortion with increasing temperature toward T_(4) is revealed by the structural analysis.
基金Under the auspices of National Natural Science Foundation of China(No.41771140)National Key R&D Program of China(No.2018YFE0105900)。
文摘As the major source of air pollution,sulfur dioxide(S0_(2))emissions have become the focus of global attention.However,existing studies rarely consider spatial effects when discussing the relationship between foreign direct investment(FDI)and S0_(2) emissions.This study took the Yangtze River Delta as the research area and used the spatial panel data of 26 cities in this region for 2004-2017.The study investigated the spatial agglomeration effects and dynamics at work in FDI and S0_(2) emissions by using global and local measures of spatial autocorrelation.Then,based on regression analysis using a results of traditional ordinary least squares(OLS)model and a spatial econometric model,the spatial Durbin model(SDM)with spatial-time effects was adopted to quantify the impact of FDI on S0_(2) emissions,so as to avoid the regression results bias caused by ignoring the spatial effects.The results revealed a significant spatial autocorrelation between FDI and S0_(2) emissions,both of which displayed obvious path dependence characteristics in their geographical distribution.A series of agglomeration regions were observed on the spatial scale.The estimation results of the SDM showed that FDI inflow promoted S0_(2) emissions,which supports the pollution haven hypothesis.The findings of this study are significant in the prevention and control of air pollution in the Yangtze River Delta.
文摘The non-isothermal decomposition reaction of Nd[(C_5H_ 10NS_2)_3(C_ 12H_8N_2)] were carried out by means of TG-DTG and the thermal decomposition mechanism, and the associated kinetics was investigated. The kinetic parameters are obtained from an analysis of the TG-DTG curves at different heating rate by integral and differential methods. The most probable kinetic model function of the decomposition reaction is Maple Power of n=3/2, f(α)=2/3α -1/2 and the apparent activation energy E is 116.67 kJ·mol -1 and the pre-exponential factor lg[A/s -1] is 7.6891.
