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生态化视角下反腐困境的赦免制度完善(二)——基于治贪困境的思辨路径
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作者 张明良 《山西师大学报(社会科学版)》 2015年第S2期32-33,共2页
本文是《生态化视角下反腐困境的赦免制度完善研究》(一)一文的续文。本文认为要妥善处理当下腐败问题,应当在历史中、思辨中寻求答案。本文主要借助后一条分析路径进行展开,着重分析笔者所提出的治贪力度化、生态化理念及介绍笔者设想... 本文是《生态化视角下反腐困境的赦免制度完善研究》(一)一文的续文。本文认为要妥善处理当下腐败问题,应当在历史中、思辨中寻求答案。本文主要借助后一条分析路径进行展开,着重分析笔者所提出的治贪力度化、生态化理念及介绍笔者设想的有条件赦免制度及其必要性与可行性。 展开更多
关键词 反腐 力度化 生态 赦免
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论后劳教时代的社会与刑事立法之应对——关于犯罪化问题的研究 被引量:1
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作者 李瑞生 《新疆财经大学学报》 2014年第2期52-61,共10页
后劳教时代,正处于风险社会的鼎盛期,后劳教时代社会冲突加剧,群体性事件增多,它是仇恨犯罪多发的时代,也是失范的时代。因而对危害社会的行为适时予以犯罪化处理,是社会发展的需要。后劳教时代,疏而多漏的刑事法网难以有效预防和制止... 后劳教时代,正处于风险社会的鼎盛期,后劳教时代社会冲突加剧,群体性事件增多,它是仇恨犯罪多发的时代,也是失范的时代。因而对危害社会的行为适时予以犯罪化处理,是社会发展的需要。后劳教时代,疏而多漏的刑事法网难以有效预防和制止越来越多的严重侵害社会的行为,迫切需要予以大力度的犯罪化处理,以有效保护法益、保护社会、保障人权、保障社会的健康和谐发展。 展开更多
关键词 后劳教时代 疏而多漏的刑事法网 力度犯罪
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Evaluation of the slipstream in different regions around a train with respect to different nose lengths:A comparison study
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作者 WANG Lei LIU Tang-hong +3 位作者 CHEN Zheng-wei ZENG Guang-zhi HEMIDA Hassan XIA Yu-tao 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3295-3311,共17页
In this work,the flow surrounding the train was obtained using a detached eddy simulation(DES)for slipstream analysis.Two different streamlined nose lengths were investigated:a short nose(4 m)and a long nose(9 m).The ... In this work,the flow surrounding the train was obtained using a detached eddy simulation(DES)for slipstream analysis.Two different streamlined nose lengths were investigated:a short nose(4 m)and a long nose(9 m).The time-average slipstream velocity and the time-average slipstream pressure along the car bodies were compared and explained in detail.In addition to the time-averaged values,the _(max)imum velocities and the pressure peak-to-peak values around the two trains were analyzed.The result showed that the nose length affected the slipstream velocity along the entire train length at the lower and upper regions of the side of the train.However,no significant effect was recognized at the middle height of the train along its length,except in the nose region.Moreover,within the train’s side regions(y=2.0-2.5 m and z=2-4 m)and(y=2.5-3.5 m and z=0.2-0.7 m),the ratio of slipstream velocity U_(max) between the short and long nose trains was notably higher.This occurrence also manifested at the train’s upper section,specifically where y=0-2.5 m and z=4.2-5.0 m.Similarly,regarding the ratio of _(max)imum pressure peak-to-peak values Cp-p_(max),significant regions were observed at the train’s side(y=1.8-2.6 m and z=1-4 m)and above the train(y=0-2 m and z=3.9-4.8 m). 展开更多
关键词 high-speed train nose length slipstream velocity pressure change
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Damage and fracture behavior and spatio-temporal evolution of acoustic emission of sandstone before and after laser radiation
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作者 GAO Ming-zhong LIU Jun-jun +6 位作者 LIChun-xiang YANG Ben-gao LI Fei ZHOU Xue-min YANG Lei YANG Zun-dong XIE Jing 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第9期3264-3280,共17页
Laser technology holds significant promise for enhancing rock-breaking efficiency.Experimental investigations were carried out on sandstone subjected to laser radiation,aiming to elucidate its response mechanism to su... Laser technology holds significant promise for enhancing rock-breaking efficiency.Experimental investigations were carried out on sandstone subjected to laser radiation,aiming to elucidate its response mechanism to such radiation.The uniaxial compressive strength of sandstone notably decreases by 22.1%–54.7%following exposure to a 750 W laser for 30 s,indicating a substantial weakening effect.Furthermore,the elastic modulus and Poisson ratio of sandstone exhibit an average decrease of 33.7%and 25.9%,respectively.Simultaneously,laser radiation reduces the brittleness of sandstone,increases the dissipated energy proportion,and shifts the failure mode from tensile to tension-shear composite failure.Following laser radiation,both the number and energy of acoustic emission events in the sandstone register a substantial increase,with a more dispersed distribution of these events.In summary,laser radiation induces notable damage to the mechanical properties of sandstone,leading to a substantial decrease in elastic energy storage capacity.Laser rock breaking technology is expected to be applied in hard rock breaking engineering to significantly reduce the difficulty of rock breaking and improve rock breaking efficiency. 展开更多
关键词 laser rock breaking efficient drilling acoustic emission mechanical damage strength reduction
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Synthesis of polyfarnesene based on aqueous free-radical polymerization and molecular dynamics simulation of its properties
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作者 WU Ming-li JIANG Jing +2 位作者 WANG Xiao-yu WANG Can-cai WANG Qing-fu 《合成橡胶工业》 CAS 2024年第6期507-507,共1页
Farnesene monomer,obtained through the bio-fermentation,offered a unique long side chain structure that served as an excellent platform for the synthesis of“bottlebrush-like”polymers with exceptional thermal propert... Farnesene monomer,obtained through the bio-fermentation,offered a unique long side chain structure that served as an excellent platform for the synthesis of“bottlebrush-like”polymers with exceptional thermal properties.Such polymers had immense potential in the production of polyurethane elastomers and adhesives.Hydroxyl-terminated polyfarnesene(PFD),which was safe,environmentally-friendly and pollution-free,was synthesized with farnesene as the monomer and industrial grade product hydrogen peroxide as the initiator by aqueous free-radical polymerization. 展开更多
关键词 properties. RADICAL MONOMER
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Preparation and mechanical properties of carbon/carbon composites with high textured pyrolytic carbon matrix 被引量:8
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作者 李伟 李贺军 +3 位作者 王杰 张守阳 杨茜 魏建锋 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第7期2129-2134,共6页
Short carbon fiber felts with an initial porosity of 89.5% were deposited by isobaric, isothermal chemical vapor infiltration using natural gas as carbon source. The bulk density of the deposited carbon/carbon (C/C)... Short carbon fiber felts with an initial porosity of 89.5% were deposited by isobaric, isothermal chemical vapor infiltration using natural gas as carbon source. The bulk density of the deposited carbon/carbon (C/C) composites was 1.89 g/cm3 after depositing for 150 h. The microstructure and mechanical properties of the C/C composites were studied by polarized light microscopy, X-ray diffraction, scanning electron microscopy and three-point bending test. The results reveal that high textured pyrolytic carbon is deposited as the matrix of the composites, whose crystalline thickness and graphitization degree highly increase after heat treatment. A distinct decrease of the flexural strength and modulus accompanied by the increase of the toughness of the C/C composites is found to be correlated with the structural changes in the composites during the heat treatment process. 展开更多
关键词 carbon/carbon composites high texture chemical vapor infiltration graphitization degree mechanical properties
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Microstructural evolution of ultra-high strength Al-Zn-Cu-Mg-Zr alloy containing Sc during homogenization 被引量:11
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作者 李文斌 潘清林 +2 位作者 肖艳苹 何运斌 刘晓艳 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第10期2127-2133,共7页
The microstructural evolution and composition distribution of an Al-Zn-Cu-Mg-Sc-Zr alloy during homogenization were investigated by optical microscopy(OM),scanning electron microscopy(SEM),energy dispersive spectr... The microstructural evolution and composition distribution of an Al-Zn-Cu-Mg-Sc-Zr alloy during homogenization were investigated by optical microscopy(OM),scanning electron microscopy(SEM),energy dispersive spectrometry(EDS),X-ray diffraction(XRD) and differential scanning calorimetry(DSC).The results show that severe dendritic segregation exists in Al-Zn-Cu-Mg-Sc-Zr alloy ingot.There are a lot of eutectic phases at grain boundary and the distribution of the main elements varies periodically along interdendritic region.The main eutectic phases at grain boundary are Al7Cu2Fe phase and T(Al2Mg3Zn3).The residual phases are dissolved into the matrix gradually during homogenization with increasing temperature and prolonging holding time,which can be described by a constitutive equation in exponential function.The overburnt temperature of the alloy is 473.9 ℃.The optimum parameters of homogenization are 470 ℃ and 24 h,which is consistent with the result of homogenization kinetic analysis. 展开更多
关键词 Al-Zn-Cu-Mg-Sc-Zr alloy HOMOGENIZATION microstructural evolution overburnt temperature homogenization kinetics
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Effects of Loading Methods on the Color,Phenolic and Antioxidant Properties of Cured Tobacco Leaves
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作者 傅茂润 赵双 +12 位作者 侯连涛 曲清莉 代红飞 董梅 苏建东 刘广玉 杨举田 王梅勋 田雷 杨永花 谭效磊 徐硕 宗浩 《Agricultural Science & Technology》 CAS 2014年第7期1196-1199,共4页
[Objective] To investigate the effects of different loading methods on tobacco leaf quality.[Method] With tobacco comb,tobacco clamp,and tobacco basket,color,phenolic compounds and their antioxidant capacity of flue-c... [Objective] To investigate the effects of different loading methods on tobacco leaf quality.[Method] With tobacco comb,tobacco clamp,and tobacco basket,color,phenolic compounds and their antioxidant capacity of flue-cured tobacco leaves were studied.[Result] The results showed that L*,a* and b* values of tobacco leaves packaged by tobacco clamp and comb were higher than those of tobacco basket and no significant differences were found beween values of a* and b*,however,between L* and h values,remarkable differences existed among three loading methods.Total phenolic content and chlorogenic acid content of tobacco leaves loaded by tobacco comb kept the highest,followed by smoke clamp and tobacco basket (P<0.05).On the other hand,rutin content showed little differences among treatments.The order of the antioxidant properties,such as DPPH free radical scavenging activity and reducing powder,of tobacco leaves by different loading methods was tobacco comb > tobacco clamp > loose basket and a positive relationship was found of antioxiang property with total phenolic content and chlorogenic acid content.[Conclusion] In view of tobacco leaves quality and antioxidant property,loading method with tobacco comb proved to be a better choice. 展开更多
关键词 PHENOLIC Color parameters Antioxidant capacity loading method Tobacco leaves
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Simulated and experimental investigation on discontinuous dynamic recrystallization of a near-α TA15 titanium alloy during isothermal hot compression in βsingle-phase field 被引量:5
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作者 武川 杨合 李宏伟 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第6期1819-1829,共11页
A cellular automaton(CA) modeling of discontinuous dynamic recrystallization(DDRX) of a near-α Ti-6Al-2Zr-1Mo-1V(TA15) isothermally compressed in the β single phase field was presented.In the CA model,nucleati... A cellular automaton(CA) modeling of discontinuous dynamic recrystallization(DDRX) of a near-α Ti-6Al-2Zr-1Mo-1V(TA15) isothermally compressed in the β single phase field was presented.In the CA model,nucleation of the β-DDRX and the growth of recrystallized grains(re-grains) were considered and visibly simulated by the CA model.The driving force of re-grain growth was provided by dislocation density accumulating around the grain boundaries.To verify the CA model,the predicted flow stress by the CA model was compared with the experimental data.The comparison showed that the average relative errors were10.2%,10.1%and 6%,respectively,at 1.0,0.1 and 0.01 s^-1 of 1020 ℃,and were 10.2%,11.35%and 7.5%,respectively,at 1.0,0.1and 0.01 s^-1 of 1050 ℃.The CA model was further applied to predicting the average growth rate,average re-grain size and recrystallization kinetics.The simulated results showed that the average growth rate increases with the increasing strain rate or temperature,while the re-grain size increases with the decreasing strain rate;the volume fraction of recrystallization decreases with the increasing strain rate or decreasing temperature. 展开更多
关键词 discontinuous dynamic recrystallization cellular automaton dislocation density evolution recrystallization kinetics TA15 titanium alloy
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Potential Function and Thermodynamic Property of UO
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作者 曾秀琳 徐司雨 居学海 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2013年第1期51-53,I0003,共4页
Potential energy scan for uranium oxide (UO) was performed by ab initio configuration inter- action (CI) method and density functional theory methods at the PBE1 and the B3LYP levels in combination with the (ECPS... Potential energy scan for uranium oxide (UO) was performed by ab initio configuration inter- action (CI) method and density functional theory methods at the PBE1 and the B3LYP levels in combination with the (ECPSOMWB_AVQZ+2f) basis set for uranium and 6-311+G* for oxygen. The dissociation energies of UO, after being corrected for the zero-point vibrational energy, are 2.38, 3.76, and 3.31 eV at the CI, PBE1, and BaLYP levels, respectively. The calculated energy was fitted to potential functions of Morse, Lennard-Jones, and Rydberg. Only the Morse function is eligible for the potential. The anharmonieity constant is 0.00425. The anharmonic frequency is 540.95 em-1 deduced from the PBE1 results. Thermodynamic properties of entropy and heat capacity at 298.2-1500 K were calculated using DFT-UPBE1 results and Morse parameters. The relationship between entropy and temperature was established. 展开更多
关键词 Potential function Uranium oxide Density functional theory Thermodynamicproperty
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Thermodynamic model of lead oxide activity in PbO-CaO-SiO_2-FeO-Fe_2O_3 slag system
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作者 汪金良 温小椿 张传福 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第5期1633-1639,共7页
According to the ion and molecule coexistence theory, a thermodynamic model of lead oxide activity in PbO-CaO-SiO2-FeO-Fe2O3 slag system was established at the temperature of 1273-1733 K. The activities of Pb O in sla... According to the ion and molecule coexistence theory, a thermodynamic model of lead oxide activity in PbO-CaO-SiO2-FeO-Fe2O3 slag system was established at the temperature of 1273-1733 K. The activities of Pb O in slag were calculated, and their equal activity curves were plotted. The influences of slag basicity Q, iron oxide rate R and temperature T on activity NPb O and activity coefficient γPbO were also investigated. Results show that the calculated values of γPb O are in good agreement with the reported experimental data, showing that the model can wholly embody the slag structural characteristics. NPbO departures positively from Raoult values, and increases with increasing Pb O content in slag but changes little with T. γPbO increases with increasing Q, and goes through the maximum with increasing R for basic slag(Q0.3). Results can be applied to the thermodynamic research and operational optimization of modern lead smelting technologies. 展开更多
关键词 ion and molecule coexistence theory thermodynamic model lead oxide ACTIVITY
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Dynamic characteristics of high stressed red sandstone subjected to unloading and impact loads 被引量:12
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作者 GONG Feng-qiang ZHONG Wen-hui +2 位作者 GAO Ming-zhong SI Xue-feng WU Wu-xing 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第2期596-610,共15页
In the process of deep projects excavation,deep rock often experiences a full stress process from high stress to unloading and then to impact disturbance failure.To study the dynamic characteristics of three-dimension... In the process of deep projects excavation,deep rock often experiences a full stress process from high stress to unloading and then to impact disturbance failure.To study the dynamic characteristics of three-dimensional high stressed red sandstone subjected to unloading and impact loads,impact compression tests were conducted on red sandstone under confining pressure unloading conditions using a modified split Hopkinson pressure bar.Impact disturbance tests of uniaxial pre-stressed rock were also conducted(without considering confining pressure unloading effect).The results demonstrate that the impact compression strength of red sandstone shows an obvious strain rate effect.With an approximately equal strain rate,the dynamic strength of red sandstone under confining unloading conditions is less than that in the uniaxial pre-stressed impact compression test.Confining pressure unloading produces a strength-weakening effect,and the dynamic strength weakening factor(DSWF)is also defined.The results also indicate that the strain rate of the rock and the incident energy change in a logarithmic relation.With similar incident energies,unloading results in a higher strain rate in pre-stressed rock.According to the experimental analysis,unloading does not affect the failure mode,but reduces the dynamic strength of pre-stressed rock.The influence of confining pressure unloading on the shear strength parameters(cohesion and friction angle)is discussed.Under the same external energy impact compression,prestressed rock subjected to unloading is more likely to be destroyed.Thus,the effect of unloading on the rock mechanical characteristics should be considered in deep rock project excavation design. 展开更多
关键词 deep rock excavation unloading unloading confining pressure three-dimensional high stress strengthweakening effect impact disturbance
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Strength evolution law of cracked rock based on localized progressive damage model 被引量:4
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作者 张平 李夕兵 李宁 《Journal of Central South University of Technology》 EI 2008年第4期493-497,共5页
In the light of the localized progressive damage model,the evolution law of cohesive and frictional strength with irreversible strains was determined.Then,the location and the extent of the excavation disturbed zone i... In the light of the localized progressive damage model,the evolution law of cohesive and frictional strength with irreversible strains was determined.Then,the location and the extent of the excavation disturbed zone in one deep rock engineering were predicted by using the strength evolution law.The theoretical result is close to the result of in-situ test.The strength evolution law excels the elastic-perfectly plastic model and elasto-brittle plastic model in which the cohesive and frictional strength are mobilized simultaneously.The results obtained indicate that the essential failure mechanism of the cracked rock can be described by the cohesion weakening and friction strengthening evolution law. 展开更多
关键词 rock mechanics STRENGTH failure mechanism LOCALIZATION evolution law
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Stress evolution of deep surrounding rock under characteristics of bi-modulus and strength drop 被引量:5
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作者 CHEN Shao-jie ZHAO Zeng-hui +1 位作者 FENG Fan ZHANG Ming-zhong 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第2期680-692,共13页
Aiming at the circular chamber under uniform stress field in deep energy storage and mining,analytical solutions of stress and plastic zone of the surrounding rock under different far-field stress and internal pressur... Aiming at the circular chamber under uniform stress field in deep energy storage and mining,analytical solutions of stress and plastic zone of the surrounding rock under different far-field stress and internal pressure were derived based on bi-modulus theory and the elastic-brittle-ideal plastic constitutive model.Evolution trend of the elasticplastic stress and plastic region with different elastic constant ratios and residual strength coefficients were analyzed in details.Results revealed that when the internal pressure was small,the three-direction principal stress was compressive stress and the stress field distribution of the surrounding rock was not affected by the moduli difference.The obtained solution was consistent with the solution from the elastic-brittle plastic drop model under the equal modulus theory.On the other hand,when the internal pressure was large,the tangential stress was changed.The surrounding rock can be divided into three zones,i.e.,tensile plastic zone(TPZ),tensile elastic zone(TEZ)and compressive elastic zone(CEZ).The tensile and compressive dual modulus had significant influence on the demarcation point between TEZ and CEZ.In addition,the strength drop and the dual modulus characteristic had a coupling effect on the stress distribution in the surrounding rock.The related achievements further enrich the theory of deep rock mechanics. 展开更多
关键词 deep surrounding rock bi-modulus strength drop stress evolution
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Microstructure and magnetic properties of FeAs with coarse-grain and nanocrystalline structure 被引量:1
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作者 Yuan ZHOU Yun-yan WANG +5 位作者 Yan-jie LIANG Yi-wei ZHOU Zhen-xing LIU Cong PENG Yong KE Xiao-bo MIN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第3期972-979,共8页
The microstructure and magnetic properties of iron arsenide(FeAs) with coarse-grain and nanocrystalline structure were investigated. Coarse-grain FeAs was synthesized through high-energy ball milling and heat treatmen... The microstructure and magnetic properties of iron arsenide(FeAs) with coarse-grain and nanocrystalline structure were investigated. Coarse-grain FeAs was synthesized through high-energy ball milling and heat treatment. Nanocrystalline FeAs was obtained by ball milling of coarse-grain FeAs. The results suggest that the reduced grain size of FeAs(from >100 to 32.4 nm) is accompanied by the introduction of internal strains up to 0.568% with ball milling time from 0 to 32 h. The magnetic properties of FeAs show that the coercivity is reduced from 29.2 to 15.6 kA/m and the magnetization is increased over time of milling. The low coercivity is mainly due to the small grain size stemmed from ball milling, while the increase of magnetization is primarily caused by the change of lattice parameters of FeAs and the emergence of superparamagnetic phase at the same time. 展开更多
关键词 high-energy ball milling iron arsenide COERCIVITY MAGNETIZATION
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A kinetic approach to evaluate salinity effects on carbon mineralization in a plant residue-amended soil 被引量:5
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作者 NOURBAKHSH Farshid SHEIKH-HOSSEINI Ahmad R. 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第10期788-793,共6页
The interaction of salinity stress and plant residue quality on C mineralization kinetics in soil is not well understood. A laboratory experiment was conducted to study the effects of salinity stress on C mineralizati... The interaction of salinity stress and plant residue quality on C mineralization kinetics in soil is not well understood. A laboratory experiment was conducted to study the effects of salinity stress on C mineralization kinetics in a soil amended with alfalfa, wheat and corn residues. A factorial combination of two salinity levels (0.97 and 18.2 dS/m) and four levels of plant residues (control, alfalfa, wheat and corn) with three replications was performed. A first order kinetic model was used to describe the C mineralization and to calculate the potentially mineralizable C. The CO2-C evolved under non-saline condition, ranged from 814.6 to 4842.4 mg CO2-C/kg in control and alfalfa residue-amended soils, respectively. Salinization reduced the rates of CO2 evolution by 18.7%, 6.2% and 5.2% in alfalfa, wheat and corn residue-amended soils, respectively. Potentially mineralizable C (Co) was reduced significantly in salinized alfalfa residue-treated soils whereas, no significant difference was observed for control treatments as well as wheat and corn residue-treated soils. We concluded that the response pattern of C mineralization to salinity stress depended on the plant residue quality and duration of incubation. 展开更多
关键词 Salinity stress Carbon mineralization First-order kinetics Plant residues Residue quality
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Molecular Dynamics Simulations for Melting Temperatures of SrF2 and BaF2
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作者 黄晓玉 程新路 +2 位作者 樊超磊 陈琼 苑晓丽 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2009年第3期310-314,340,共6页
The shell-model molecular dynamics method was applied to simulate the melting temper- atures of SrF2 and BaF2 at elevated temperatures and high pressures. The same method was used to calculate the equations of state f... The shell-model molecular dynamics method was applied to simulate the melting temper- atures of SrF2 and BaF2 at elevated temperatures and high pressures. The same method was used to calculate the equations of state for SrF2 and BaF2 over the pressure range of 0.1 MPa-3 GPa and 0.1 MPa-7 GPa. Compared with previous results for equations of state, the maximum errors are 0.3% and 2.2%, respectively. Considering the pre-melting in the fluorite-type crystals, we made the necessary corrections for the simulated melting temper- atures of SrF2 and BaF2. Consequently, the melting temperatures of SrF2 and BaF2 were obtained for high pressures. The melting temperatures of SrF2 and BaF2 that were obtained by the simulation are in good agreement with available experimental data. 展开更多
关键词 Molecular dynamics simulation Melting temperature Equation of state HIGHPRESSURE
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Temperature Effect on Boron Adsorption-Desorption Kinetics in Soils 被引量:3
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作者 ZHUDUANWEI SHILEI 《Pedosphere》 SCIE CAS CSCD 1999年第3期243-250,共8页
The effect of temperature on the properties of boron adsorption-desorption in brown-red soil, yellowbrown soil and calcareous alluvial soil of Hubei Province was investigated with the mobile displacement technique. Th... The effect of temperature on the properties of boron adsorption-desorption in brown-red soil, yellowbrown soil and calcareous alluvial soil of Hubei Province was investigated with the mobile displacement technique. The experimental data of B adsorption-desorption amounts and reaction t line at 25 and 40℃ were fitted by the zero-order, first-order and parabolic diffusion kinetic equations. The adsorption process was in conformity with the parabolic diffusion law at both the temperatures, and the values of rate constant of the parabolic diffusion equation in B adsorption were 0.138, 0.124 and 0.105 mg kg-1 min-1/2 at 25℃, and 0.147, 0.146 and 0.135 mg kg-1 min-1/2 at 40℃ for the brown-red soil, yellow-brown soil, and calcareous alluvial soil, respectively. The relationship between amount of B desorption and reaction time could be well described by the first-order kinetic equation, and the corresponding values of rate constant were 0.0422, 0.0563 and 0.0384 min-1 at 25℃, and 0.0408, 0.042 3 and 0.0401 min-1 at 40℃ for the brown-red soil, the yellow-brown soil and the calcareous alluvial soil, respectively. Therefore, the desorption process of B might be related to the amount of B adsorbed in soil. The higher the temperature, the lower the amount of B adsorption for the same soil in the same reaction time. The values of the apparent activation energy of B adsorption in the three soils calculated with the rate constants of parabolic diffusion equation were 3.27, 8.44 and 12.99 kJ mol-1, respectively, based on the experimental data of B adsorption amounts and reaction time at 25 and 40℃. 展开更多
关键词 activation energy ADSORPTION-DESORPTION hinetics soil boron TEMPERATURE
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Strength weakening effect of high static pre-stressed granite subjected to low-frequency dynamic disturbance under uniaxial compression 被引量:8
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作者 Wu-xing WU Feng-qiang GONG Quan JIANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第7期2353-2369,共17页
This study aimed to elucidate the strength weakening effect of high static pre-stressed rocks subjected to low-frequency disturbances under uniaxial compression.Based on the uniaxial compressive strength(UCS)of granit... This study aimed to elucidate the strength weakening effect of high static pre-stressed rocks subjected to low-frequency disturbances under uniaxial compression.Based on the uniaxial compressive strength(UCS)of granite under static loading,70%,80%,and 90%of UCS were selected as the initial high static pre-stress(σ_(p)),and then the pre-stressed rock specimens were disturbed by sinusoidal stress with amplitudes of 30%,20%,and 10%of UCS under low-frequency frequencies(f)of 1,2,5,and 10 Hz,respectively.The results show that the rockburst failure of pre-stressed granite is caused by low-frequency disturbance,and the failure strength is much lower than UCS.When theσp or f is constant,the specimen strength gradually decreases as the f or σ_(p) increases.The experimental study illustrates the influence mechanism of the strength weakening effect of high static pre-stress rocks under low-frequency dynamic disturbance,that is,high static pre-stress is the premise and leading factor of rock strength weakening,while low-frequency dynamic disturbance induces rock failure and affects the strength weakening degree. 展开更多
关键词 deep rock high static pre-stress low-frequency dynamic disturbance strength weakening effect uniaxial compression ROCKBURST
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Dynamics study on effect of temperature to Nitrous nitrification reaction of coking wastewater 被引量:2
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作者 单明军 张海灵 吕艳丽 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第3期311-315,共5页
Dynamic effects of NO2--N accumulation were discussed owing to temperature.In different temperature,a series of vmax and Ks were found considering the relation between the temperature and rate of ammonia nitrogen tran... Dynamic effects of NO2--N accumulation were discussed owing to temperature.In different temperature,a series of vmax and Ks were found considering the relation between the temperature and rate of ammonia nitrogen transforming into NO2--N.The kinetics models,which reflected the conditions of ammonia nitrogen transforming into NO2--N in the treatment process of the coking wastewater,were built up.The characteristic coefficient temperature was determined according to Arrhenius. 展开更多
关键词 nitrite nitrogen coking wastewater KINETICS TEMPERATURE
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