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铜合金表层原子胞体运动的类液振荡模拟
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作者 杨新娥 朱学敏 +1 位作者 高后秀 杨渝钦 《天津大学学报(自然科学与工程技术版)》 EI CAS CSCD 北大核心 2003年第5期529-533,共5页
用流体模型对铜合金表层在常温常压下出现的原子胞体的运动进行模拟分析,结果表明,这类由原子堆积而成的胞体的运动具有明显的类液振荡行为.当内摩擦增强时,波胞振幅按指数规律随时间衰减.理论分析与实验符合较好.在合金及非金属表层上... 用流体模型对铜合金表层在常温常压下出现的原子胞体的运动进行模拟分析,结果表明,这类由原子堆积而成的胞体的运动具有明显的类液振荡行为.当内摩擦增强时,波胞振幅按指数规律随时间衰减.理论分析与实验符合较好.在合金及非金属表层上都观测到了这种类液振荡花样,可以认为,固体表层上出现的这类原子位形有一定的普遍性. 展开更多
关键词 铜合金 原子 运动模拟 类液振荡 模型 波胞振幅 运动规律 运动模式
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汉语单双音节对应词的语体对立及语法属性 被引量:21
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作者 冯胜利 王永娜 王丽娟 《汉语学报》 CSSCI 北大核心 2021年第2期2-17,共16页
本文讨论单双音节对应词(下称"单双词")在语体语法理论体系中出现和存在的原因。文章指出,虽然以往对单双词的现象及存在方式有多方面的观察和研究,但它们存在的原理及其语言学性质,迄今没有深入讨论和一致看法。本文认为,单... 本文讨论单双音节对应词(下称"单双词")在语体语法理论体系中出现和存在的原因。文章指出,虽然以往对单双词的现象及存在方式有多方面的观察和研究,但它们存在的原理及其语言学性质,迄今没有深入讨论和一致看法。本文认为,单双词是汉语韵律语体语法系统的产物,而它们在语义、词法、句法、语用和韵律等诸多方面的对立,都是语距定律下体原子在语言各个部门的作用和表现,因此单双词现象是汉语韵律语体语法机制派生的自然结果。 展开更多
关键词 单双音节对应词 韵律语法 语法 语距定律 体原子
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First-principles study on the structure-property relationship of AlX and InX(X=N,P,As,Sb)
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作者 HE Zhihao DING Jiafu +1 位作者 WANG Yunjie SU Xin 《无机化学学报》 北大核心 2025年第5期1007-1019,共13页
This paper delves into the theoretical mechanisms of the electronic structure and optical properties of aluminum-based semiconductors(AlX,X=N,P,As,Sb)and indium-based semiconductors(InX,X=N,P,As,Sb)as potential materi... This paper delves into the theoretical mechanisms of the electronic structure and optical properties of aluminum-based semiconductors(AlX,X=N,P,As,Sb)and indium-based semiconductors(InX,X=N,P,As,Sb)as potential materials for optical devices.Band structure calculations reveal that,except for InSb,all other compounds are direct bandgap semiconductors,with AlN exhibiting a bandgap of 3.245 eV.The valence band maximum of these eight compounds primarily stems from the p-orbitals of Al/In and X.In contrast,the conduction band minimum is influenced by all orbitals,with a predominant contribution from the p-orbitals.The static dielectric constant increased with the expansion of the unit cell volume.Compared to AlX and InX with larger X atoms,AlN and InN showed broader absorption spectra in the near-ultraviolet region and higher photoelectric conductance.Regarding mechanical properties,AlN and InN displayed greater shear and bulk modulus than the other compounds.Moreover,among these eight crystal types,a higher modulus was associated with a lower light loss function value,indicating that AlN and InN have superior transmission efficiency and a wider spectral range in optoelectronic material applications. 展开更多
关键词 aluminium‑based semiconductor indium‑based semiconductor first principle electronic structure optical property
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Effect and mechanism of dolomite with different size fractions on hematite flotation using sodium oleate as collector 被引量:10
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作者 罗溪梅 印万忠 +3 位作者 王云帆 孙传尧 马英强 刘建 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第3期529-534,共6页
The effect of dolomite with different particle size fractions on hematite flotation was studied using sodium oleate as collector at p H of about 9. The effect mechanism of dolomite on hematite flotation was investigat... The effect of dolomite with different particle size fractions on hematite flotation was studied using sodium oleate as collector at p H of about 9. The effect mechanism of dolomite on hematite flotation was investigated by means of solution chemistry, ultraviolet spectrophotometry(UV), inductively coupled plasma atomic emission spectrometry(ICP-AES) and X-ray photoelectron spectroscopy(XPS). It is observed that dolomite with different size fractions has depressing effect on hematite flotation using sodium oleate as collector, and dolomite could be the "mineral depressant" of hematite using sodium oleate as collector. The reasons for that are concerned with sodium oleate consumption and the adsorption onto hematite of dissolved species of dolomite. 展开更多
关键词 DOLOMITE HEMATITE sodium oleate mineral dissolution depressing effect
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Facile synthesis of Zn_2GeO_4 nanorods toward improved photocatalytic reduction of CO_2 into renewable hydrocarbon fuel 被引量:4
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作者 杨明 金效齐 《Journal of Central South University》 SCIE EI CAS 2014年第7期2837-2842,共6页
Zn2GeO4 nanorods were prepared by a surfactant-assisted solution phase route.The as-prepared products were characterized by X-ray powder diffraction(XRD),scanning electron microscopy(SEM),high-resolution transmission ... Zn2GeO4 nanorods were prepared by a surfactant-assisted solution phase route.The as-prepared products were characterized by X-ray powder diffraction(XRD),scanning electron microscopy(SEM),high-resolution transmission electron microscopy(HRTEM),inductively coupled plasma atomic emission spectrometer(ICP-AES),UV-vis diffuse reflection spectroscopy and photoluminescence(PL) spectroscopy.The possible formation mechanism of Zn2GeO4 nanorods was discussed.It was supposed that the CTA+ cations preferentially adsorb on the planes of Zn2GeO4 nanorods,leading to preferential growth along the c-axis to form the Zn2GeO4 rods with larger aspect ratio and higher surface area,which showed the improved photocatalytic activity for photoreduction of CO2.The photoluminescence(PL) property of Zn2GeO4 nanorods was investigated through the emission spectra. 展开更多
关键词 PHOTOCATALYSIS Zn2GeO4 nanorod cetyl trimethyl ammonium bromide(CTAB)
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Heavy metals accumulation effect in rabbit body fluids after smoking 被引量:2
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作者 钟狂飚 桂明 +3 位作者 朱立勇 李维 管茶香 郭方遒 《Journal of Central South University》 SCIE EI CAS 2011年第5期1408-1412,共5页
Concentration of heavy metals in blood and urine of rabbit after inhaling three different kinds of cigarette was studied through the animal passive smoking pattern. The samples were prepared by nitric acid solution di... Concentration of heavy metals in blood and urine of rabbit after inhaling three different kinds of cigarette was studied through the animal passive smoking pattern. The samples were prepared by nitric acid solution digestion and determination of seven kinds of heavy metals including Hg, Se, Sn, Pb, Cd, Ni and Cr was performed by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The ICP-AES method was established with good precision and accuracy, relative standard deviation (n=6) was between 2.9% and 5.9%, and the recovery was in the range of 95.0%-104.2%. Concentration of six heavy metals increases in some extent in blood and urine after period of smoking and the increasing of heavy metals in blood and urine all shows time dependence. Significantly higher heavy metal levels are observed in the blood and urine of the cigarette inhaling rabbits in the exposed group. The concentration of six kinds of heavy metals in the blood of the rabbit increases after 16 weeks exposing to cigarette smoking. Three times of rig, ten times of Se and trace amount ofPb, Cd, Ni and Cr are detected in the blood after 16 weeks of smoking. For urine samples, about three times of Hg, two times of Se, five times of Pb and trace amount of Cd are detected after 16 weeks of inhalation of cigarette. Comparatively, higher concentration of heavy metals are detected after inhaling of Nise cigarette. 展开更多
关键词 inductively coupled plasma-atomic emission spectrometry BLOOD URINE heavy metal element
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Dissolution behavior of calcium-magnesium-silicate glass fiber 被引量:1
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作者 刘浩 王玺堂 +1 位作者 张保国 王周福 《Journal of Central South University》 SCIE EI CAS 2011年第6期1833-1837,共5页
The dissolution behavior of CaO-MgO-SiO2 glass fiber was investigated by scanning electron microscopy (SEM), Fourier-transform infrared spectrometer (FTIR) and inductively coupled plasma atomic emission spectrosco... The dissolution behavior of CaO-MgO-SiO2 glass fiber was investigated by scanning electron microscopy (SEM), Fourier-transform infrared spectrometer (FTIR) and inductively coupled plasma atomic emission spectroscopy (ICP-AES) using in-vitro tests. The results show that the soaked fiber is surrounded by an outer calcium-magnesium silicate hydrated layer, and there exists a balancing fimction between the formation and abscission of the hydrated layer during the dissolution process. The concentrations of leached ions increase constantly, and the mass loss of the fibers and pH changes of the solution are found to rise rapidly during the initial dissolution process, then their increasing rates are controlled by the balancing function of the hydrated layer at the subsequent dissolution stages. The dissolution rate constant and time for complete dissolution are estimated to be 274 ng/(cm2.h) and 15.2 d, respectively, presenting preferable biosolubilities. 展开更多
关键词 calcium-magnesium-silicate glass glass fiber DISSOLUTION hydrated layer
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Modulating absorption band of triangular silver nanoplates in aqueous solvent and on substrates using tannin as reducing agent 被引量:2
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作者 易早 牛高 +5 位作者 韩尚君 罗江山 陈善俊 叶鑫 易有根 唐永建 《Journal of Central South University》 SCIE EI CAS 2011年第5期1365-1370,共6页
Triangular silver nanoplates in aqueous solvent and on the surface of quartz substrate have been synthesized by seed-mediated growth approach in the presence of tannin.It was found that both the amount of tannin and t... Triangular silver nanoplates in aqueous solvent and on the surface of quartz substrate have been synthesized by seed-mediated growth approach in the presence of tannin.It was found that both the amount of tannin and the small triangular silver nanoplate seeds added to the growth solution are the key factors to modulation absorption band of triangular silver nanoplates.The optical in-plane dipole surface plasmon resonance (SPR) bands of these Ag nanoplates can be tuned from 608 nm to 980 nm via tannin deoxidization method.The formation mechanism of triangular silver nanoplates was proposed.The tannin deoxidization method realizes a convenient modulation of the absorption band of Ag nanostructures within the visible near-infrared (IR) region both in aqueous solvent and on substrates under mild conditions. 展开更多
关键词 silver nanoplate TANNIN seed-mediated growth surface plasmon resonance near-infrared region
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Evaluation of metal-doped manganese oxide octahedral molecular sieves in catalytic reduction of NO_x from cigarette mainstream smoke 被引量:1
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作者 练文柳 任凤莲 +1 位作者 刘琦 谢兰英 《Journal of Central South University》 SCIE EI CAS 2012年第4期918-922,共5页
A series of Ag,Cu and Co-doped manganese oxide octahedral molecular sieves(OMS-2) were synthesized and evaluated to remove nitrogen oxides(NOx) from cigarette mainstream smoke.The three kinds of catalysts were added t... A series of Ag,Cu and Co-doped manganese oxide octahedral molecular sieves(OMS-2) were synthesized and evaluated to remove nitrogen oxides(NOx) from cigarette mainstream smoke.The three kinds of catalysts were added to cigarettes for studying the capabilities of reducing NOx from cigarette mainstream smoke.The catalysis and reduction of NO in laboratory were studied.A mechanism for NOx catalytic reduction from burning cigarettes with the catalysts adding to cigarettes was described.The catalysts show excellent catalytic activity for NOx removal,especially the Ag-doped OMS-2 catalyst.0.5%(mass fraction) Ag-doped OMS-2 catalyst has the best ability to remove NOx from cigarette mainstream smoke.The use of Ag-doped OMS-2 as catalyst for removing carcinogenic compounds from cigarette smoke will be an effective strategy to protect the environment and public health. 展开更多
关键词 nitrogen oxides CATALYST manganese oxide octahedral molecular sieve METALS cigarette mainstream smoke
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Mathematical modeling and analysis of gas torque in twin-rotor piston engine
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作者 邓豪 潘存云 +1 位作者 徐小军 张湘 《Journal of Central South University》 SCIE EI CAS 2013年第12期3536-3544,共9页
The gas torque in a twin-rotor piston engine(TRPE) was modeled using adiabatic approximation with instantaneous combustion. The first prototype of TRPE was manufactured. This prototype is intended for high power densi... The gas torque in a twin-rotor piston engine(TRPE) was modeled using adiabatic approximation with instantaneous combustion. The first prototype of TRPE was manufactured. This prototype is intended for high power density engines and can produce 36 power strokes per shaft revolution. Compared with the conventional engines, the vector sum of combustion gas forces acting on each rotor piston in TRPE is a pure torque, and the combustion gas rotates the rotors while compresses the gas in the compression chamber at the same time. Mathematical modeling of gas force transmission was built. Expression for gas torque on each rotor was derived. Different variation patterns of the volume change of working chamber were introduced. The analytical and numerical results is presented to demonstrate the main characteristics of gas torque. The results show that the value of gas torque in TRPE falls to be less than zero before the combustion phase is finished; the time for one stroke is 30° in terms of the rotating angle of the output shaft; gas torque in one complete revolution of the output shaft has a period which is equal to 60° and it is necessary to put off the moment when gas torque becomes zero in order to export the maximum energy. 展开更多
关键词 ROTOR piston engine gas torque power density adiabatic process
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