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Chinese Physics Letters 2010年第12期27卷 173-176页

作者：王华林丁万昱刘超前柴卫平 School of Materials Science and Engineering Dalian diaotong University Dalian 116028 Engineering Research Center of Optoelectronic Materials and Devices Education Department of Liaoning Province Dalian 116028

Indium tin oxide （ITO） films were deposited on glass substrates at room temperature by dc pulse magnetron sputtering. Varying 02 flux, ITO films with different properties are obtained. Both x-ray diffractometer and x-ray photoelectron spectrometer are used to study the change of crystalline structures and bonding structures of ITO films, respectively. Electrical properties are measured by four-point probe measurements. The results indicate that the chemical structures and compositions of ITO films strongly depend on the O2 flux. With increasing O2 flux, ITO films display better crystallization, which could decrease the resistivity of films. On the contrary, ITO films contain less O vacancies with increasing O2 flux, which could worsen the conductive properties of films. Without any heat treatment onto the samples, the resistivity of the ITO film could reach 6.0 × 10^-4 Ω·cm, with the optimal deposition parameter of 0.2 scem O2 flux.

关键词： OxYGEN INDIUM compounds TEMPERATURE effect DIRECT currents MAGNETRON sputtering x-ray diffractometer x-ray photoelectron spectroscopy

Pressure dependence of the thermal stability in LiMn_(2)O_(4)

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Chinese Physics B 2022年第1期31卷 453-457页

作者： Yan Zeng Hao Liang Shixue Guan Junpu Wang Wenjia Liang Mengyang Huang Fang Peng Institute of Atomic and Molecular Physics Sichuan UniversityChengdu 610065China School of Science Southwest University of Science and TechnologyMianyang 621010China

Structural stability in terms of the decomposition temperature in LiMn_(2)O_(4) was systematically investigated by a series of high-temperature and high-pressure ***_(2)O_(4) was found to have structural stability up to 5 GPa at room *** ambient pressure,the compound decomposed at 1300℃.The decomposition temperature decreased with increasing pressure,yielding more complex decomposed *** the decomposition temperature,the crystal structure of LiMn_(2)O_(4) varied with *** presented results in this study offer new insights into the thermal and pressure stability of LiMn_(2)O_(4) materials as a cathode for lithium-ion batteries that can operate under extreme ***,these findings may serve as a useful guide for future work for improving lithium-ion batteries.

关键词： LiMn_(2)O_(4) high pressure x-ray diffractometer decomposition reactions

Growth of Erbium Dihydride Films under Low Hydrogen Pressure by Pulsed Laser Deposition

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Journal of Wuhan University of Technology(Materials Science) 2015年第1期30卷 33-36页

作者：王雪敏 SHEN Changle WANG Yuying PENG Liping LI Weihua YAN Dawei 吴卫东 TANG Yongjian Science and Technology on Plasma Physics Laboratory Research Center of Laser Fusion China Academy of Engineering Physics

Erbium dihydride thin films were prepared by pulsed laser deposition on Si（100） substrates using erbium target under different low hydrogen pressures. The properties of these films were examined by atomic force microscopy, x-ray diffractometer, transmission electron microscopy, and Fourier transform infrared spectroscopy and UV-vis spectroscopy. Surface morphology reveals the smooth surface of these films （RMS： from 0.503 to 2.849 nm）. The presence of obviously-broadened peaks for diffraction planes （111） suggests a presence of very tiny crystallites distributed along a preferred crystallographic orientation. Transmission electron microscopy investigations confirmed the formation of tiny crystallites due to the implantation of erbium ions. Due to the increase of nominal H concentration, the intensity of the broad absorbance from 190-260 nm increased.

关键词： thin films pulsed laser deposition x-ray diffractometer transmission electron microscopy

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Chemical Composition and Crystal Structure of the Eggshell of the Green Crested Lizard Bronchocela cristatella(Agamidae)

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Asian Herpetological Research 2021年第4期12卷 331-336页

作者： Kun GUO Jun ZHONG Li MA Yongpu ZHANG xiang JI College of Life and Environmental Sciences Wenzhou UniversityWenzhou 325035ZhejiangChina Faculty of Ecology Lishui UniversityLishui 323000ZhejiangChina

The majority of extant reptiles are oviparous and produce eggs with three major components:embryo,yolk,and *** eggshell is species-specific and more diverse in squamate reptiles than in other amniote ***,we study the crystal structure,chemical composition,and bonding states of the eggshell of the green crested lizard Bronchocela cristatella.x-ray diffractometer(xRD)analysis showed the existence of two clearly defined and distinguishable crystalline phases,aragonite and *** the xRD data and a unit cell refinement routine,we identified two sets of cell parameters:a=4.956 A,b=7.965 A,and c=5.734 A for the aragonite phase;a=4.987 A,b=4.987 A,and c=17.056 A for the calcite *** used x-ray photoelectron spectroscopy to examine detailed elemental composition and bonding states and found that the eggshell was composed primarily of elements C,N,Ca,and O,with C,N and O bonded to various types of hybridization in the protein of the eggshell *** Ca:C:O ratio for the calcium carbonate yielded a value of-7:8:21,which is close to the expected stoichiometric value of CaCO3.

关键词： agamid lizard aragonite calcite crystal structure eggshell elemental bonding states x-ray diffractometer x-ray photoelectron spectroscopy

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Pressure dependence of the thermal stability in Li Mn2O4

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Chinese Physics B 2022年第1期31卷 531-535页

作者：曾彦梁浩管诗雪王俊普梁文嘉黄梦阳彭放 Institute of Atomic and Molecular Physics Sichuan University School of Science Southwest University of Science and Technology

Structural stability in terms of the decomposition temperature in LiMn2O4was systematically investigated by a series of high-temperature and high-pressure ***2O4was found to have structural stability up to 5 GPa at room *** ambient pressure,the compound decomposed at 1300 ℃.The decomposition temperature decreased with increasing pressure,yielding more complex decomposed *** the decomposition temperature,the crystal structure of LiMn2O4varied with *** presented results in this study offer new insights into the thermal and pressure stability of LiMn2O4materials as a cathode for lithium-ion batteries that can operate under extreme ***,these findings may serve as a useful guide for future work for improving lithium-ion batteries.

关键词： LiMn2O4 high pressure x-ray diffractometer decomposition reactions

Radiological and x-ray Diffraction Characterization of Bauxite and Rutile Ore Contaminated Environment in Kanam and Wase Mineral Exploration Sites, Plateau State-Nigeria

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Journal of Environmental Protection 2023年第10期14卷 841-858页

作者： Adams Udoji Itodo raymond Ahulle Wuana Ishaq Shaibu Eneji Emmanuel Duwongs Bulus Department of Chemistry Joseph Sarwuan Tarka University Makurdi Nigeria

Two non-destructive analytical techniques (gamma spectrometer and x-ray diffractometer) were employed in the analysis of bauxite and rutile ore and their vicinity soil and control sourced within the Kanam and Wase mineral exploration sites. The activity concentrations of natural radionuclides 238U, 232Th, and 40K in the soil samples received from bauxite and rutile mineral mining vicinities revealed high concentrations of 238U, 232Th, and 40K compared to the control soil samples sourced 500 m away from the mineral exploration vicinities. Radiological detriments RLI, AUI, Hin and Hex unveiled values exceeding the radiation standard concentration (>1) for soil. x-ray diffraction characterization of bauxite ore revealed the interlocking minerals of Bauxite (18)%, Albite (11)%, Garnet (15)%, Illite (6)% and Muscovite (43)% in various proportions obtained within the 2θ range (9.18 to 64.4) and a peak value (intensity, cps) of 3400. Pure bauxite percentage in the ore meets metallurgical grade (15 - 25)%. x-ray diffraction of rutile ore revealed the minerals of rutile (40)%, quartz (21.4)%, ilmenite (27)% and garnet (11.8)% found within the 2θ range (27.5 to 35.6) and a peak value intensity of 31.1 - 100.0 cps also meeting the metallurgical grade of 15% - 25%. The major environmental concern associated with the mineral-sands industry is the radiation hazards, pollution of ground-water sources from heavy metals, mineral transport with heavy equipment’s, dredging operations in fragile coastal area and clearing of vegetation.

关键词： Radiology Mineralogy Mining Bauxite and Rutile Ores Environmental Contamination Radiological detriments x-ray diffractometer Gamma Spectrometer Control Soil

Crystallity Change of Compressed Poplar Wood Treated by PF Resin

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Chinese Forestry Science and Technology 2006年第1期5卷 8-13页

作者： ZHOU Haibin LIU Junliang JIANG Zehui Research Institute of Wood Industry Chinese Academy of Forestry Beijing 100091. P.R. China

This study investigated the effect of weight percent gain （WPG） and compression set on the crystallity of compressed poplar wood. Tests were conducted to determine the mechanism of compressed wood set. The samples of 1-72 Poplar were treated with a PF resin of water-solubility and low molecular weight. Then the air-dried samples were hot-pressed to a certain thickness. Finally the specimens were obtained from the compressed samples and scanned with an x-ray diffractometer. Results show that before press the crystallity of the inner layer is lower than that of the outer layer, and at press the difference of the crystallity between the outer layer and the inner layer will slowly disappear and finally the crystallity of the inner layer exceeds that of the outer layer; with the increasing compression set the crystallity decreases, and there is a big decrease; the crystallity difference between two layers happens because of compression set gradient, WPG difference or the joint effect.

关键词： crystallity PF resin plantation forest x-ray diffractometer WPG compression set permanent set Poplar (Poplar euramaricana cv. 1-72)

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SYNTHESIS OF LEAD FREE SODIUM BISMUTH TITANATE(NBT)CERAMIC BY CONVENTIONAL AND MICROWAVE SINTERING METHODS

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Journal of Advanced Dielectrics 2011年第1期1卷 71-77页

作者： M.VENKATA RAMANA S.ROOPAS KIRAN N.RAMAMANOHAR REDDY K.V.SIVA KUMAR V.R.K.MURTHY B.S.MURTY Ceramic Composite Materials Laboratory Department of Physics Sri Krishnadevaraya UniversityAnantapur 515003India Microwave Laboratory Department of Physics Indian Institute of Technology Chennai 600036India Nanotechnology Laboratory Department of Metallurgical and Materials Engineering Indian Institute of Technology Chennai 600036 India

Dielectric studies were carried out on a lead free Sodium Bismuth Titanate,NBT,(Na_(0.5)Bi_(0.5)TiO_(3))*** material was synthesized by conventional ceramic method(CS)and microwave sintering(MS).The presence of single phase has been confirmed by x-ray diffraction and scanning electron microscopy of NBT *** later technique(MS)resulted in material with high density,dielectric properties and improved *** transition temperature was observed slightly higher for microwave sintered(MS)*** modulus measurements are very sensitive property to identify the phase transitions in *** modulus(L)measurements were also employed on these samples in the frequency 136 kHz and can be studied in the wide temperature range 30℃to 400℃.The elastic behavior(L)showed a break at two temperatures(~200℃and 350℃)in both the conventional and microwave sintered *** NBT ceramics,permittivity anomalies are connected to modulus *** results are correlated with the dielectric *** behavior explained in the light of structural phase transitions in the ferroelectric ceramics.

关键词： Microwave sintering NBT x-ray diffractometer scanning electron microscopy dielectric properties longitudinal modulus