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Effect of KOH treatment on structural and photovoltaic properties of ZnO nanorod arrays 被引量:2
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作者 周艺 李荡 +3 位作者 黄燕 何文红 肖斌 李宏 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第11期2736-2741,共6页
ZnO nanorod arrays (NRs) were synthesized on the fluorine-doped SnO2 transparent conductive glass (FTO) by a simple chemical bath deposition (CBD) method combined with alkali-etched method in potassium hydroxide... ZnO nanorod arrays (NRs) were synthesized on the fluorine-doped SnO2 transparent conductive glass (FTO) by a simple chemical bath deposition (CBD) method combined with alkali-etched method in potassium hydroxide (KOH) solution. X-ray diffraction (XRD), scanning electron microscopy (SEM) and current-voltage (I-V) curve were used to characterize the structure, morphologies and optoelectronic properties. The results demonstrated that ZnO NRs had wurtzite structures, the morphologies and photovoltaic properties of ZnO NRs were closely related to the concentration of KOH and etching time, well-aligned and uniformly distributed ZnO NRs were obtained after etching with 0.1 mol/L KOH for 1 h. ZnO NRs treated by KOH had been proved to have superior photovoltaic properties compared with high density ZnO NRs. When using ZnO NRs etched with 0.1 mol/L KOH for 1 h as the anode of solar cell, the conversion efficiency, short circuit current and open circuit voltage, compared with the unetched ZnO NRs, increased by 0.71%, 2.79 mA and 0.03 V, respectively. 展开更多
关键词 ZnO nanorod arrays SnO2 transparent conductive glass alkali etching structural properties photovoltaic properties solar cells
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Molecular Dynamics Simulations of Silica Nanotube: Structural and Vibrational Properties Under Different Temperatures
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作者 张胜利 张永红 +2 位作者 黄世萍 王鹏 田辉平 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第5期497-503,621,共8页
Four-, six-, and eight-membered ring silica nanotubes at temperatures from 300 K to 1600 K are relaxed by classical molecular dynamics simulations with three potential models. The simulation results indicate that the ... Four-, six-, and eight-membered ring silica nanotubes at temperatures from 300 K to 1600 K are relaxed by classical molecular dynamics simulations with three potential models. The simulation results indicate that the stability of the end rings of the three silica nanotubes gradually decreases with increase in temperature. The validity of the vibrational features of silica nanotubes is shown by the vibrational density of states. Infrared spectra on the silica nanotubes under different temperatures are investigated. A detailed assignment of each spectral peak to the corresponding vibrational mode of the three nanotubes has been addressed. The results are in good agreement with the other theoretical and experimental 展开更多
关键词 SiliCa nanotube Molecular dynamics structural property Vibrational densityof state Infrared spectrum
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Effects of Different Drying Methods on the Functional and Structural Properties of Dietary Fiber from Peanut Shell 被引量:5
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作者 Lei WANG Xishuang XING +6 位作者 Yang LIU Tian LIN Sining TANG Xin ZHOU Zhijun LIU Huihui CAO Yanhua YAN 《Agricultural Biotechnology》 CAS 2020年第3期128-132,共5页
[Objectives] This study was conducted to investigate the drying methods,functional and structure properties of dietary fiber( DF) from peanut shells.[Methods]Peanut shells were used as a raw material to prepare peanut... [Objectives] This study was conducted to investigate the drying methods,functional and structure properties of dietary fiber( DF) from peanut shells.[Methods]Peanut shells were used as a raw material to prepare peanut shell dietary fiber( DF) by hot air drying( HA) and vacuum freeze drying( VF),respectively,and their functional and structural characteristics were compared in detail. [Results]The solubility,water holding capacity,oil holding capacity and swelling capacity of HA-DF and VF-DF were 2. 15 %,7. 63 g/g,7. 73 g/g,10. 35 ml/g and 3. 85 %,14. 98 g/g,15. 25 g/g,15. 85 ml/g,respectively. The total phenol contents were 2. 623 and 5. 173 mg GAE/g,respectively. The IC(50) values of ·OH,O2^-· and DPPH free radicals were 4. 16 and 4. 09 mg/ml,7. 90 and 3. 32 mg/ml,and 3. 19 and 3. 09 mg/ml,respectively. The molecular weight of VF-DF was smaller,and it had narrow molecular weight distribution and denser particles. Electron microscopy showed that VF-DF had a porous network like honeycomb and swelled structure. [Conclusions]This study can provide a theoretical basis for the functional modification and comprehensive utilization of peanut shell dietary fiber. 展开更多
关键词 Peanut shell Dietary fiber Drying method Functional property structural property
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Investigation of the structural, electronic and mechanical properties of CaO–SiO_(2) compound particles in steel based on density functional theory 被引量:1
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作者 Chao Gu Ziyu Lyu +1 位作者 Qin Hu Yanping Bao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第4期744-755,共12页
CaO–SiO_(2)compounds compromise one of the most common series of oxide particles in liquid steels, which could significantly affect the service performance of the steels as crack initiation sites. However, the struct... CaO–SiO_(2)compounds compromise one of the most common series of oxide particles in liquid steels, which could significantly affect the service performance of the steels as crack initiation sites. However, the structural, electronic, and mechanical properties of the compounds in CaO–SiO_(2)system are still not fully clarified due to the difficulties in the experiments. In this study, a thorough investigation of these properties of CaO–SiO_(2)compound particles in steels was conducted based on first-principles density functional theory. Corresponding phases were determined by thermodynamic calculation, including gamma dicalcium silicate(γ-C2S), alpha-prime(L) dicalcium silicate(αL′-C2S), alpha-prime(H) dicalcium silicate(αH′-C2S), alpha dicalcium silicate(α-C2S), rankinite(C3S2), hatrurite(C3S), wollastonite(CS), and pseudowollastonite(Ps-CS). The results showed that the calculated crystal structures of the eight phases agree well with the experimental results. All the eight phases are stable according to the calculated formation energies, and γ-C2S is the most stable. O atom contributes the most to the reactivity of these phases. The Young’s modulus of the eight phases is in the range of 100.63–132.04 GPa. Poisson’s ratio is in the range of0.249–0.281. This study provided further understanding concerning the CaO–SiO_(2)compound particles in steels and fulfilled the corresponding property database, paving the way for inclusion engineering and design in terms of fracture-resistant steels. 展开更多
关键词 CaO–SiO_(2) density functional theory structural property electronic property mechanical property
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Unusual structural properties of polymers confined in a nanocylinder
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作者 江志斌 彭梦杰 +3 位作者 李林玲 周东山 汪蓉 薛奇 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期392-395,共4页
Structural properties of polymers confined in nanocylinders are investigated by Monte Carlo simulation, which is successfully used to consider the conformational property of constrained polymers. The conformational pr... Structural properties of polymers confined in nanocylinders are investigated by Monte Carlo simulation, which is successfully used to consider the conformational property of constrained polymers. The conformational properties of the polymers close to the walls exhibit different features. The density profiles of polymers are enhanced near the wall of the nanocylinder, which shows that the packing densities differ near the wall and far from the wall. The highest densities near the wall of the nanocylinder decrease with increasing radius of the nanocylinder. Furthermore, the density excess is not only near the wall of the nanocylinder, but also shifts to the center of the nanocylinder at lower temperatures. The radius of gyration and the bond length of polymers in the nanocylinder show that the polymer chains tend to extend along the axis of the nanocylinder in highly confined nanocylinder and contract at lower temperature. Our results are very helpful in understanding the packing induced physical behaviors of polymers in nanocylinders, such as glass transition, crystallization,etc. 展开更多
关键词 POLYMER CONFINEMENT nanocylinder structural property
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Effects of N_2 Pressure on the Structural and Electrical Properties of TiN Films Deposited by Laser Molecular Beam Epitaxy
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作者 符跃春 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第5期823-826,共4页
Titanium nitride (TiN) films were deposited on Si(100) substrates by laser molecular beam epitaxy(LMBE),and their properties of structure and resistivity with varying N2 pressure were investigated.The results sh... Titanium nitride (TiN) films were deposited on Si(100) substrates by laser molecular beam epitaxy(LMBE),and their properties of structure and resistivity with varying N2 pressure were investigated.The results showed that atomically flat TiN films with layer-by-layer growth mode were successfully grown on Si(100) substrates,and (200) was the preferred orientation.With the increasing of N2 pressure,the N/Ti ratio gradually increased and the diffraction peak progressively shifted towards lower diffraction angle.At pressure of 0.1 Pa,stoichiometric TiN film was formed which exhibited the characteristic diffraction angle of (200) plane.All films showed high reflectance to infrared spectrum and the films with overstoichiometry and understoichiometry had a higher resistivity owing to the surface particles and lattice distortion,while the stoichiometric TiN film depicted the minimum resistivity,around 19 μΩ·cm. 展开更多
关键词 titanium nitride laser molecular beam epitaxy structural property RESISTIVITY
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STRUCTURAL PROPERTIES INVESTIGATION ON MICROCRYSTALLINE SILICON FILMS DEPOSITED WITH VHF-PECVD TECHNIQUE
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作者 H.D.Yang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2005年第3期223-227,共5页
Raman scattering spectroscopy and scanning electron microscopy (SEM) techniques were used to determine the structural properties of two typical series of microc rystalline silicon (μc-Si:H) films deposited at differe... Raman scattering spectroscopy and scanning electron microscopy (SEM) techniques were used to determine the structural properties of two typical series of microc rystalline silicon (μc-Si:H) films deposited at different VHF plasma power and different working gas pressure by very high frequency plasma enhanced chemical v apor deposition (VHF-PECVD) technique. Raman spectra measurements show that both crystalline volume fraction Xc and average grain size d of μc-Si : H films ar e strongly affected by the two deposition conditions and are more sensitive to w orking gas pressure than VHF plasma power. SEM characterizations have further co nfirmed that VHF plasma power and working gas pressure could clearly enhance the surface roughness of μc-Si : H films ascribing to polymerization reactions, w hich is also more sensitive to working gas pressure than VHF plasma power. 展开更多
关键词 VHF-PECVD microcrystalline silicon film structural property
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EFFECTS OF ALENDRONATE ON STRUCTURAL PROPERTIES OF TRABECULAR BONE IN DOGS
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作者 胡建华 张良 +1 位作者 赵立连 黄公怡 《Chinese Medical Sciences Journal》 CAS CSCD 2002年第4期210-214,共5页
Objective. To evaluate the effects of alendronate on the structural properties of trabecular bone.Methods. Alendronate was administered at a daily p. o. dose of 0. 5 mg/kg over a 12-week period in hound dogs (n = 8 fo... Objective. To evaluate the effects of alendronate on the structural properties of trabecular bone.Methods. Alendronate was administered at a daily p. o. dose of 0. 5 mg/kg over a 12-week period in hound dogs (n = 8 for both the control and treated group), and the structural indices of the lumbar vertebral (LI and L2) trabecular bone were assessed directly from 3-D images.Results. Treatment with alendronate increased bone volume fraction by 9. 5% and 7. 7% in L1 and L2 respectively. Trabecular thickness significantly increased after alendronate treatment, whereas trabecular separation remained constant. The degree of anisotropy for the alendronate - treated group was decreased compared with that of the control group. Bone surface to volume ratio declined significantly in the alendronate-reated group, whereas alendronate induced a higher bone surface density.Conclusion. Alendronate increased the structural properties of canine trabecular bone after short-term treatment at a dose of 0. 5 mg · kg-1·day-1. 展开更多
关键词 trabecular bone ALENDRONATE structural property
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Effect of Cadmium Substitution on Structural and Magnetic Properties of Nano Sized Nickel Ferrite
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作者 Sanjay Pralhadrao Jadhav Bhagwan Ghanshamji Toksha +1 位作者 Kamalakar Marutirao Jadhav Shinde Dadarao Shinde 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第4期459-464,I0002,共7页
The structure and crystal phase of the nanocrystalline powders of Ni1-xCdxFe2O4(0≤x≤0.5) mixed ferrite, synthesized by wet chemical co-precipitation method, were characterized by X-ray diffraction. Results showed ... The structure and crystal phase of the nanocrystalline powders of Ni1-xCdxFe2O4(0≤x≤0.5) mixed ferrite, synthesized by wet chemical co-precipitation method, were characterized by X-ray diffraction. Results showed that the lattice parameter increased with increasing Cd concentration. Microstructure was studied by scanning electron microscopy. TG/DTA studies were carried out on co-precipitated sulphate complexes. These studies revealed the low ferritization temperature (650 ℃) of the ferrite system synthesized by presently adopted route of synthesis and occurrence of simultaneous decomposition and ferritization processes. Further studies by infrared spectroscopy were also conducted. Moreover, magnetic properties of the prepared nanoparticles were studied by magnetization and a.c. susceptibility measurements. The response of prepared Ni1-xCdxFe2O4 mixed ferrites to magnetic field was investigated. Results show that, magnetic susceptibility, Curie temperature, and effective magnetic moment decreased as the Cd content increases. 展开更多
关键词 FERRITE structural property Magnetic property
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Effect of Root Architecture on Structural Stability and Erodibility of Topsoils during Concentrated Flow in Hilly Loess Plateau 被引量:13
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作者 LI Qiang LIU Guobin +2 位作者 ZHANG Zheng TUO Dengfeng XU Mingxiang 《Chinese Geographical Science》 SCIE CSCD 2015年第6期757-764,共8页
Traditional vegetation techniques for the control of concentrated flow erosion are widely recognized, whereas only a few studies have experimentally investigated the impacts of belowground roots on the erodibility of ... Traditional vegetation techniques for the control of concentrated flow erosion are widely recognized, whereas only a few studies have experimentally investigated the impacts of belowground roots on the erodibility of topsoils in semi-arid areas. To quantify the effects of root architectures on soil erodibility and its relevant structural properties, simulated flow experiments were conducted at six-week intervals from 18 July to 20 October in 2012 in the hilly Loess Plateau. Five treatments were: 1) bare(control), 2) purple alfalfa(Medicago sativa), representing tap roots(T), 3) switchgrass(Panicum virgatum), representing fibrous roots(F), 4) purple alfalfa and switchgrass, representing both tap and fibrous roots(T + F), and 5) natural recovery(N). For each treatment, soil structural properties and root characteristics were measured at an interval of six weeks. Soil anti-scouribility was calculated. Results showed that grass planting slightly reduced soil bulk density, but increased soil aggregate content by 19.1%, 10.6%, 28.5%, and 41.2% in the treatments T, F, T + F, and N, respectively. Soil shear strength(cohesion and angle of internal friction(φ)) significantly increased after the grass was planted. As roots grew, soil cohesion increased by 115.2%–135.5%, while soil disintegration rate decreased by 39.0%–58.1% in the 21 th week compared with the recorded value in the 9th week. Meanwhile, root density and root surface area density increased by 64.0%–104.7% and 75.9%–157.1%, respectively. No significant differences in soil anti-scouribility were observed between the treatments of T and F or of T + F and N, but the treatments of T + F and N performed more effectively than T or F treatment alone in retarding concentrated flow. Soil aggregation and root surface-area density explained the observed soil anti-scouribility during concentrated flow well for the different treatments. This result proved that the restoration of natural vegetation might be the most appropriate strategy in soil reinforcement in the hilly Loess Plateau. 展开更多
关键词 fibrous roots tap roots root density soil structural properties soil anti-scouribility hilly Loess Plateau China
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Influence of oxygen gas content on the structural and optical properties of ZnO thin films deposited by RF magnetron sputtering at room temperature 被引量:6
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作者 LIU Baoting ZHOU Yang +4 位作者 ZHENG Hongfang LI Mana GUO Zhe HAO Qingxun PENG Yingcai 《Rare Metals》 SCIE EI CAS CSCD 2011年第2期170-174,共5页
Zinc oxide (ZnO) thin films were deposited on sapphire (0001) substrates at room temperature by radiofrequency (RF) magnetron sputtering at oxygen gas contents of 0%, 25%, 50% and 75%, respectively. The influenc... Zinc oxide (ZnO) thin films were deposited on sapphire (0001) substrates at room temperature by radiofrequency (RF) magnetron sputtering at oxygen gas contents of 0%, 25%, 50% and 75%, respectively. The influence of oxygen gas content on the structural and optical properties of ZnO thin films was studied by a surface profile measuring system, X-ray diffraction analysis, atomic force microscopy, and UV spectro- photometry. It is found that the size of ZnO crystalline grains increases first and then decreases with the increase of oxygen gas content, and the maximum grain size locates at the 25% oxygen gas content. The crystalline quality and average optical transmittance (〉90%) in the visi- ble-light region of the ZnO film prepared at an oxygen gas content of 25% are better than those of ZnO films at the other contents. The obtained results can be attributed to the resputtefing by energetic oxygen anions in the growing process. 展开更多
关键词 thin films zinc oxide magnetron sputtering OXYGEN structural properties optical properties
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Synthesis, Structure and Luminescent Property of a 2D Cd(Ⅱ) Coordination Polymer Based on Mixed-ligands of 1,3-Bis(imidazol)propane and Pyridine-3,5-dicarboxylic Acid 被引量:19
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作者 卢久富 刘举 +1 位作者 姜敏 葛红光 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第2期248-252,共5页
A new Cd(Ⅱ) coordination polymer, namely, [Cd(1,3-bip)(3,5-pdc)]n (1,3-bip = 1,3-bis(imidazol)propane and 3,5-pdc = pyridine-3,5-dicarboxylic acid) has been synthesized under hydrothermal conditions. Compou... A new Cd(Ⅱ) coordination polymer, namely, [Cd(1,3-bip)(3,5-pdc)]n (1,3-bip = 1,3-bis(imidazol)propane and 3,5-pdc = pyridine-3,5-dicarboxylic acid) has been synthesized under hydrothermal conditions. Compound 1 was characterized by infrared spectrum, elemental analysis, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction analysis. It crystallizes in monoclinic, space group P21/c with a = 1.40178(7), b = 1.72502(12), c = 1.41635(6) ran, β = 92.653(4)°, V = 3.4212(3) nm3, Z = 4, C16HIsCdNsO4, Mr = 453.73, Dc = 1.762 g/cm3, F(000) = 1808,μ = 1.310 mm1, R = 0.0899 and wR = 0.1945. In compound 1, each 3,5-pdc ligand links three Cd(lI) ions and each Cd(Ⅱ) attaches to bip ligands to form a complicated 2D double-layer structure. In addition, the thermal stability and luminescent property of 1 have been studied in the solid state at room temperature. 展开更多
关键词 Cd(Ⅱ) coordination polymer MIXED-LIGANDS crystal structure luminescent property
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Structural Characterization and Octanol/water Partition Coefficients(LogP) Prediction for Oxygen-containing Organic Compounds 被引量:8
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作者 廖立敏 黄茜 雷光东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第8期1243-1250,共8页
New descriptors were constructed and structures of some oxygen-containing organic compounds were parameterized. The multiple linear regression(MLR) and partial least squares regression(PLS) methods were employed t... New descriptors were constructed and structures of some oxygen-containing organic compounds were parameterized. The multiple linear regression(MLR) and partial least squares regression(PLS) methods were employed to build two relationship models between the structures and octanol/water partition coefficients(LogP) of the compounds. The modeling correlation coefficients(R) were 0.976 and 0.922, and the "leave one out" cross validation correlation coefficients(R(CV)) were 0.973 and 0.909, respectively. The results showed that the structural descriptors could well characterize the molecular structures of the compounds; the stability and predictive power of the models were good. 展开更多
关键词 oxygen-containing organic compounds octanol/water partition coefficients(LogP) structural descriptors relationship between structures and properties
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Synthesis and measurement of structural and magnetic properties of K-doped LaCoO_3 perovskite materials 被引量:3
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作者 Manjunath B.Bellakki C.Madhu +3 位作者 Tobias Greindl Sandeep Kohli Patrick McCurdy V.Manivannan 《Rare Metals》 SCIE EI CAS CSCD 2010年第5期491-500,共10页
Polycrystalline La1-xKxCoO3 (0≤ x ≤ 0.2) rare earth cobaltates have been synthesized by a solution combustion method using glycine as a fuel. The synthesized ceramic materials were characterized by powder X-ray di... Polycrystalline La1-xKxCoO3 (0≤ x ≤ 0.2) rare earth cobaltates have been synthesized by a solution combustion method using glycine as a fuel. The synthesized ceramic materials were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and magnetic measurements and studied for physical properties, such as photoeatalytic activity. FTIR measurements in conjunction with XRD showed that phases beyond 10% K doping are accompanied by small amounts of impurities. Chemical titrations show the presence of Co^4+ and account for the Co^3+-Co^4+ mixed-valency of the system. The parent LaCoO3 shows spin-glass transition at low temperatures, whereas doped samples show transition from spin-glass behavior to paramagnetic ordering on progressive doping of K. "Mixed-conductor" nature of these ceramics positions them as viable candidates for solid oxide fuel cell (SOFC) applications. 展开更多
关键词 ceramic materials combustion synthesis X-ray diffraction magnetic properties structural properties
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A Quantitative Structure Property Relationship for Prediction of Flash Point of Alkanes Using Molecular Connectivity Indices 被引量:3
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作者 Morteza Atabati Reza Emamalizadeh 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第4期420-426,共7页
Many structure-property/activity studies use graph theoretical indices, which are based on the topological properties of a molecule viewed as a graph. Since topological indices can be derived directly from the molecul... Many structure-property/activity studies use graph theoretical indices, which are based on the topological properties of a molecule viewed as a graph. Since topological indices can be derived directly from the molecular structure without any experimental effort, they provide a simple and straightforward method for property prediction. In this work the flash point of alkanes was modeled by a set of molecular connectivity indices (Х), modified molecular connectivity indices ( ^mХ^v ) and valance molecular connectivity indices ( ^mХ^v ), with ^mХ^v calculated using the hydrogen perturbation. A stepwise Multiple Linear Regression (MLR) method was used to select the best indices. The predicted flash points are in good agreement with the experimental data, with the average absolute deviation 4.3 K. 展开更多
关键词 quantitative structure property relationship flash point molecular connectivity indices hydrogen perturbation ALKANE
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Effects of (LiCe) co-substitution on the structural and electrical properties of CaBi2Nb209 ceramics 被引量:3
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《Chinese Physics B》 SCIE EI CAS CSCD 2012年第3期448-452,共5页
The piezoelectric, dielectric, and ferroelectric properties of the (LiCe) co-substituted calcium bismuth niobate (CaBi2Nb209, CBNO) are investigated. The piezoelectric properties of CBNO ceramics are significantly... The piezoelectric, dielectric, and ferroelectric properties of the (LiCe) co-substituted calcium bismuth niobate (CaBi2Nb209, CBNO) are investigated. The piezoelectric properties of CBNO ceramics are significantly enhanced and the dielectric loss tan 5 decreased. This makes poling using (LiCe) co-substitution easier. The ceramics (where represents A-site Ca2+ vacancies, possess a pure layered structure phase and no other phases can be found. The Cao.ss(LiCe)0.04[]0.04Bi2Nb209 ceramics possess optimal piezoelectric properties, with piezoelectric coefficient (d33) and Curie temperature (Tc) found to be 13.3 pC/N and 960 ℃ respectively. The dielectric and piezoelectric properties of the (LiCe) co-substituted CBNO ceramics exhibit very stable temperature behaviours. This demonstrates that the CBNO ceramics are a promising candidate for ultrahigh temperature applications. 展开更多
关键词 co-substitution structural properties electrical properties CaBi2Nb209
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Effects of Sr^(2+) substitution on the structural, dielectric, and piezoelectric properties of PZT-PMN ceramics 被引量:2
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作者 Arvind Kumar S.K. Mishra 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2014年第2期175-180,共6页
This study described the structural, dielectric, and piezoelectric behavior of Pb1-xSrx[(Zr0.52Ti0.48)0.95(Mn1/3Nb2/3)0.05]O3 ceramics (PSZT-PMN, x=0, 0.025, 0.050, and 0.075), prepared by a semi-wet route. X-ra... This study described the structural, dielectric, and piezoelectric behavior of Pb1-xSrx[(Zr0.52Ti0.48)0.95(Mn1/3Nb2/3)0.05]O3 ceramics (PSZT-PMN, x=0, 0.025, 0.050, and 0.075), prepared by a semi-wet route. X-ray diffraction, dielectric, and piezoelectric investigations were carried out to analyze the crystal structure. The relative dielectric constant and dielectric loss were both calculated as the functions of temperature. The room-temperature dielectric constant reaches a maximum for a Sr2+-modified PZT-PMN ceramic with an x value of 0.050, which corresponds to the morphotropic phase boundary (MPB). Raman spectroscopy studies also confirm the existence of this MPB for x=0.050. The piezoelectric strain coefficients (d33) value shows a maximum response for this composition. In addition, the phase transition temperature decreases significantly when the Sr2+concentration increases in the PZT-PMN ceramics. 展开更多
关键词 ceramic materials STRONTIUM SUBSTITUTION structural properties dielectric properties PIEZOELECTRICITY
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Magnetic and Structural Properties in Co/Cu/Co Sandwiches with Ni and Cr Buffer Layers 被引量:2
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作者 Hollglie SHEN, Tie LI, Qinwo SHEN, Qiang PAN and Shichang ZOU (State Key Laboratory of Functional Materials for Informations and State Key Laboratories of Transducer Technology, Shanghai Institute of Metallurgy, Chinese Academy of Sciences, Shanghai 2000 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2000年第2期195-196,共2页
The magnetic and structural properties in Co/Cu/Co sandwiches with Ni and Cr buffer layers were investigated. It was found that the coercivity in Ni layer buffered samples decreases with increasing Ni layer thickness,... The magnetic and structural properties in Co/Cu/Co sandwiches with Ni and Cr buffer layers were investigated. It was found that the coercivity in Ni layer buffered samples decreases with increasing Ni layer thickness, while that in Cr layer buffered ones increases with increasing Cr layer thickness, leading to a large difference in field sensitivity of their giant magnetoresistance (GMR) properties. X-ray diffraction and high resolution transmission electron microscope images exhibited that there is a strong fcc (111) texture in the samples with Ni buffer layer. But there are only randomly oriented potycrystalline grains in Cr buffered sandwiches. According to atomic force microscope topography, the surface roughness of Cr buffered sandwiches is smaller than that of Ni buffered ones. It is demonstrated that buffer layer influences both magnetic and structural properties in Co/Cu/Co sandwiches as well as their GMR characteristics. 展开更多
关键词 CR CO HRTEM Magnetic and structural Properties in Co/Cu/Co Sandwiches with Ni and Cr Buffer Layers CU NI
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Structural, microstructural, and thermal characterizations of a chalcopyrite concentrate from the Singhbhum shear zone, India 被引量:2
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作者 Ritayan Chatterjee Shamik Chaudhuri +1 位作者 Saikat Kumar Kuila Dinabandhu Ghosh 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第3期225-232,共8页
The structural and morphological characterizations of a chalcopyrite concentrate, collected from the Indian Copper Complex, Ghatshila, India, were carried out by X-ray diffraction, scanning electron microscopy, and en... The structural and morphological characterizations of a chalcopyrite concentrate, collected from the Indian Copper Complex, Ghatshila, India, were carried out by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The con- centmte powder was composed mainly of free chalcopyrite and low quartz in about 3:1 weight ratio. The particle size was about 100 μm. Spectroscopic studies (FTIR, Raman, UV-visible) of the concentrate supported the XRD findings, and also revealed a marginal oxidation of the sulfide phase. The energy band gap of the sulfide was found to be 3.4 eV. Differential thermal analysis and thermogravimetry of the con- centrate showed a decomposition of chalcopyrite at 658 K with an activation energy of 208 kJ-mol 1, and two successive structural changes of silica at 848 K and 1145 K. 展开更多
关键词 CHALCOPYRITE structural properties MICROSTRUCTURE thermal characteristics
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First-principles simulation of Raman spectra and structural properties of quartz up to 5 GPa 被引量:2
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作者 刘雷 吕超甲 +3 位作者 庄春强 易丽 刘红 杜建国 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第12期517-525,共9页
The crystal structure and Raman spectra of quartz are calculated by using first-principles method in a pressure range from 0 to 5 GPa. The results show that the lattice constants(a, c, and V) decrease with increasin... The crystal structure and Raman spectra of quartz are calculated by using first-principles method in a pressure range from 0 to 5 GPa. The results show that the lattice constants(a, c, and V) decrease with increasing pressure and the a-axis is more compressible than the c axis. The Si–O bond distance decreases with increasing pressure, which is in contrast to experimental results reported by Hazen et al. [Hazen R M, Finger L W, Hemley R J and Mao H K 1989 Solid State Communications 725 507–511], and Glinnemann et al. [Glinnemann J, King H E Jr, Schulz H, Hahn T, La Placa S J and Dacol F 1992 Z. Kristallogr. 198 177–212]. The most striking changes are of inter-tetrahedral O–O distances and Si–O–Si angles. The volume of the SiO4^4- tetrahedron decreased by 0.9%(from 0 to 5 GPa), which suggests that it is relatively rigid.Vibrational models of the quartz modes are identified by visualizing the associated atomic motions. Raman vibrations are mainly controlled by the deformation of the Si O4-4tetrahedron and the changes in the Si–O–Si bonds. Vibrational directions and intensities of atoms in all Raman modes just show little deviations when pressure increases from 0 to 5 GPa.The pressure derivatives(dνi/d P) of the 12 Raman frequencies are obtained at 0 GPa–5 GPa. The calculated results show that first-principles methods can well describe the high-pressure structural properties and Raman spectra of quartz. The combination of first-principles simulations of the Raman frequencies of minerals and Raman spectroscopy experiments is a useful tool for exploring the stress conditions within the Earth. 展开更多
关键词 structural properties Raman mode QUARTZ first principles
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