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A Hypothesis Regarding the Origin of Additional Surface Acidity in Solid Complexes with Same Metal Cations
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作者 SHAO Bo TONG Chaoli +5 位作者 WANG Jiaqian HAN Zhongkang ZHANG Yan GE Wenfeng WANG Yong YANG Hangsheng 《材料科学与工程学报》 CAS CSCD 北大核心 2024年第5期718-722,共5页
Based on the criteria for additional surface acidity generation in composite oxides and composite fluorides proposed by Tanabe and Kemnitz et al.A hypothesis for the origin of additional surface acidity in solid compo... Based on the criteria for additional surface acidity generation in composite oxides and composite fluorides proposed by Tanabe and Kemnitz et al.A hypothesis for the origin of additional surface acidity in solid composites with the same metal cations is proposed.The surface acidsites of We analyze three types of solid composite systems,that is,CrF_(3)/Cr_(2)O_(3),MgF_(2)/MgO,and ZnF_(2)/ZnO,is systematically analyzed,which agrees with experimental results.Accordingly,the origin of additional surface acidity in these solid composites is reasonably explained,and the types of acidic sites are also predicted. 展开更多
关键词 surface acidity solid composite Local charge imbalance
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A novel surface molecularly imprinted polymer as the solid-phase extraction adsorbent for the selective determination of ampicillin sodium in milk and blood samples 被引量:6
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作者 Ningli Wu Zhimin Luo +7 位作者 Yanhui Ge Pengqi Guo Kangli Du Weili Tang Wei Du Aiguo Zeng Chun Chang Qiang Fu 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第3期157-164,共8页
Surface molecularly imprinted polymers (SMIPs) for selective adsorption of ampicillin sodium were synthesized using surface molecular imprinting technique with silica gel as a support. The physical and morphological... Surface molecularly imprinted polymers (SMIPs) for selective adsorption of ampicillin sodium were synthesized using surface molecular imprinting technique with silica gel as a support. The physical and morphological characteristics of the polymers were investigated by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), elemental analysis and nitrogen adsorption-desorption test. The obtained results showed that the SMIPs displayed great adsorption capacity (13.5 lag/mg), high recognition ability (the imprinted factor is 3.2) and good binding kinetics for ampicillin sodium. Finally, as solid phase extraction adsorbents, the SMIPs coupled with HPLC method were validated and applied for the enrichment, purification and determination of anapicillin sodium in real milk and blood samples. The averages of spiked accuracy ranged from 92.1% to 107.6%. The relative standard deviations of intra- and inter-day precisions were less than 4.6%. This study provides a new and promising method for enriching, extracting and determining ampicillin sodium in complex biological samples. 展开更多
关键词 Ampicillin sodium surface molecularly imprinted polymers solid phase extraction High performance liquid chromatography
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Surface and Texture Properties of Tb-Doped Ceria-Zirconia Solid Solution Prepared by Sol-Gel Method 被引量:6
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作者 樊国栋 冯长根 张昭 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第1期42-47,共6页
The three-way catalysts (TWCs) promoters Ce0.6Zr0.4- x TbxO2-y were prepared by sol-gel method. BET surface areas analysis indicated that an increase of the dopant Tb content from x = 0.05 to x = 0.15 favors an incr... The three-way catalysts (TWCs) promoters Ce0.6Zr0.4- x TbxO2-y were prepared by sol-gel method. BET surface areas analysis indicated that an increase of the dopant Tb content from x = 0.05 to x = 0.15 favors an increase of surface area from 66.8 to 80.4 m^2· g^-1 compared with the undoped sample Ce0 .6oZr0.40O2 65.1 m^2·g^- 1 after calcination at 650℃. Transmission electron microscopy (TEM) observation indicated that the doped samples have a higher thermal stability. The XRD and Raman spectra confirmed that the Ce0.6Zr0.4-xTbxO2-y cubic solid solution is formed. XPS analysis revealed that Ce and Tb mainly existed in the form of Ce^4+ and Tb^3 + , and Zr existed in the form of Zr^4+ on the surface of the samples. The doped samples were homogenous in composition ; the introduction of Tb into the CeO2-ZrO2 promoters resuited in the formation of a solid solution, and the concentration of surface lattice oxygen was increased. 展开更多
关键词 Ce0.6Zr0.4 - xTbxO2 - y solid solution three-way catalysts sol-gel method surface and texture structure rare earths
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SKEWED SYMMETRY DETECTION OF QUADRIC SURFACE SOLIDS UNDER ORTHOGRAPHIC PROJECTION
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作者 王翔 丁运亮 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第3期212-218,共7页
The skewed symmetry detection plays an improtant role in three-dimensional(3-D) reconstruction. The skewed symmetry depicts a real symmetry viewed from some unknown viewing directions. And the skewed symmetry detect... The skewed symmetry detection plays an improtant role in three-dimensional(3-D) reconstruction. The skewed symmetry depicts a real symmetry viewed from some unknown viewing directions. And the skewed symmetry detection can decrease the geometric constrains and the complexity of 3-D reconstruction. The detection technique for the quadric curve ellipse proposed by Sugimoto is improved to further cover quadric curves including hyperbola and parabola. With the parametric detection, the 3-D quadric curve projection matching is automatical- ly accomplished. Finally, the skewed symmetry surface of the quadric surface solid is obtained. Several examples are used to verify the feasibility of the algorithm and satisfying results can be obtained. 展开更多
关键词 three-dimensional computer graphics face reconstruction skewed symmetry detection quadric surface solid
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Immersing Treatment of Steel Plate Surface in Steel-Aluminum Solid to Liquid Bonding 被引量:2
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作者 Peng Zhang Yunhui Du +4 位作者 Xueping Ren Yonglin Kang Hanwu Liu Jianzhong Cui Limin Ba (Material Science and Engineering School, University of Science and Technique Beijing, Beijing 100083, China)(Metal Forming Department Northeastern University, Shenyang 1 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1999年第1期57-60,共4页
The interfacial status of the steel-aluminum solid to liquid bonding plates (their steel plate surfaces were or were not immersed in flux aqueous solution) were measured by using SEM (Scanning Electron Microscope) and... The interfacial status of the steel-aluminum solid to liquid bonding plates (their steel plate surfaces were or were not immersed in flux aqueous solution) were measured by using SEM (Scanning Electron Microscope) and X-ray diffraction . The results showed that the layer of flux (the minimum thickness was 15 μm on the steel plate surface) could protect the steel plate surface from oxidizing effectively at high temperature in solid to liquid bonding. The melt temperatUre of the flux should be lower than 580 ℃ so that it could be melted and removed completely. No. 1 flux (patent product made by the author) made up of halogeindes could also force liquid aluminum to infiltrate into steel plate surface and thus the interfacial shear strength of the bonding plate was rather large. 展开更多
关键词 steel-aluminum solid to liquid bonding plate steel plate surface immerse flux melt temperature interfacial shear shrength
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FOURIER-TRANSFORM INFRARED SPECTROSCOPIC STUDIES ON THE INTERACTION AMONG MARINE TRACE METAL IONS , SOLID PARTICLES AND ORGANICS Ⅱ. THE STEP WISE CHANGE IN THE SURFACE HYDROXYL GROUPS 被引量:1
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作者 王修林 张正斌 刘莲生 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1991年第2期163-169,共7页
IR spectra of Cu (Ⅱ)-marine solid particle systems show that Cu (Ⅱ)-marine solid particle ion exchange causes a stepwise change in the surface H-bonding hydroxyl groups on illite . montmorillonite, CaCO3,r. AlOOH an... IR spectra of Cu (Ⅱ)-marine solid particle systems show that Cu (Ⅱ)-marine solid particle ion exchange causes a stepwise change in the surface H-bonding hydroxyl groups on illite . montmorillonite, CaCO3,r. AlOOH and goethite, but that this does not affect the surface free hydroxyl groups on illite. montmorillonite and CaCO3. and framework hydroxyl group on goethite and on γ- AlOOH . Over the range of Cu(Ⅱ) exchange amounts in the present experiment, four stepwise changes were discovered for the surface H- bonding hydroxyl group on illite. while two stepwise changes were observed on the other marine solids. The interfacial stepwise ion exchange theory was first demonstrated by the above experimental evidence . 展开更多
关键词 HYDROXYL STEPWISE surface interfacial solid bonding STEP amorphous isotherms solids
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Effect of Preparation Method on Surface Area and Crystalline Form of CeO_2-ZrO_2 Solid Solution 被引量:1
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作者 王晓红 郭耘 +4 位作者 卢冠忠 郭杨龙 王筠松 张志刚 刘晓晖 《Journal of Rare Earths》 SCIE EI CAS CSCD 2004年第6期763-765,共3页
The CeO_2-ZrO_2 solid solutions were prepared by a reverse microemulsion method. The effect of preparation parameters on the surface area and crystalline form of the solid solutions were studied by the BET surface are... The CeO_2-ZrO_2 solid solutions were prepared by a reverse microemulsion method. The effect of preparation parameters on the surface area and crystalline form of the solid solutions were studied by the BET surface area and XRD analysis. The studies indicate that the separation of the microemulsion phase during the preparation procedure can decrease the specific surface area of sample, adding hydrogen peroxide in the matrix solution can increase the specific surface area and stability of sample. The surface area of sample calcined at 550 ℃ for 5 h is 149 m^2·g^(-1), and that calcined at 900 ℃ for 6 h is 88 m^2·g^(-1). The sample with tetragonal symmetry Ce_(0.5)Zr_(0.5)O_2 phase has a higher stability. 展开更多
关键词 reverse microemulsion method PREPARATION CeO_2-ZrO_2 solid solution high surface area crystalline form rare earths
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Isothermal superplastic solid state bonding of 40Cr and Cr12MoV steels based on surface modification 被引量:1
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作者 张柯柯 张占领 +3 位作者 刘帅 岳云 马宁 杨蕴林 《China Welding》 EI CAS 2009年第3期32-36,共5页
Based on the feasibility of isothermal superplastic solid state bonding of 40Cr and Cr12MoV steels, the surfaces of both steels to be bonded were ultra-fined through high frequency hardening, then the superplastic sol... Based on the feasibility of isothermal superplastic solid state bonding of 40Cr and Cr12MoV steels, the surfaces of both steels to be bonded were ultra-fined through high frequency hardening, then the superplastic solid state bonding were conducted, the microstructure and fracture surface of bonded joint were observed and analysed, and bonding mechanisms was researched. The experimental results show that with the sample surfaces of 4OCr and Cr12MoV steels after the high frequeney hardening, under the prepressing stress of 56. 6 MPa, initidl strain rate of 1.5 × 10^ -2 min^-1 and at the bonding temperature of800 -820℃, the superplastic solid state bonding can be carried out in about 3.5 min, and the joint strength is up to that of 40Cr steel base metal and the radial expansion ratio of the joint does not exceed 6%. The saperplastic solid state bonding parameter of both steels is within the ranges of the isothermal compressive superplastic deformation of Cr12MoV steel, and the deformation in Cr12MoV steel side near the interfacial zone of joint presents the characteristic of superplasticity. In bonding process, the atoms in two sides of joint interface have diffused each other. 展开更多
关键词 STEEL surface modification superplastic solid state bonding
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Heat Transfer in a Liquid-Solid Circulating Fluidized Bed Reactor with Low Surface Tension Media 被引量:2
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作者 H.R.Jin H.Lim +2 位作者 D.H.Lim Y.Kang Ki-Won Jun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第8期844-849,共6页
Heat transfer characteristics between the immersed heater and the bed content were studied in the riser of a liquid-solid circulating fluidized bed, whose diameter and height were 0.102 m (ID) and 2.5 m, respectively.... Heat transfer characteristics between the immersed heater and the bed content were studied in the riser of a liquid-solid circulating fluidized bed, whose diameter and height were 0.102 m (ID) and 2.5 m, respectively. Effects of liquid velocity, particle size, surface tension of liquid phase and solid circulation rate on the overall heat transfer coefficient were examined. The heat transfer coefficient increased with increasing particle size or solid circulation rate due to the higher potential of particles to contact with the heater surface and promote turbulence near the heater surface. The value of heat transfer coefficient increased gradually with increase in the surface tension of liquid phase, due to the slight increase of solid holdup. The heat transfer coefficient increased with the liquid velocity even in the higher range, due to the solid circulation prevented the decrease in solid holdup, in contrast to that in the conventional liquid-solid fluidized beds. The values of heat transfer coefficient were well correlated in terms of dimensionless groups as well as operating variables. 展开更多
关键词 heat transfer coefficient liquid-solid circulating fluidized bed liquid surface tension solid circulation rate particle size
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SEMI-ELLIPTIC SURFACE CRACK IN AN ELASTIC SOLID WITH FINITE SIZE UNDER IMPACT LOADING 被引量:1
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作者 Guo Ruiping Liu Guanting Fan Tianyou 《Acta Mechanica Solida Sinica》 SCIE EI 2006年第2期122-127,共6页
In this paper a semi-elliptic surface crack problem in an elastic solid of finite size under impact loading is investigated. An analysis is performed by means of fracture dynamics and the finite element method, and a ... In this paper a semi-elliptic surface crack problem in an elastic solid of finite size under impact loading is investigated. An analysis is performed by means of fracture dynamics and the finite element method, and a three-dimensional finite element program is developed to compute the dynamic stress intensity factor. The results reveal that the effects of the solid's boundary surface, crack surface, material inertia and stress wave interactions play significant roles in dynamic fracture. 展开更多
关键词 surface crack solid of finite size impact loading dynamic stress intensity factor finite element method
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Electrolyte-dependent formation of solid electrolyte interphase and ion intercalation revealed by in situ surface characterizations 被引量:1
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作者 Shiwen Li Chao Wang +3 位作者 Caixia Meng Yanxiao Ning Guohui Zhang Qiang Fu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第4期718-726,共9页
The formation of solid electrolyte interphase(SEI) and ion intercalation are two key processes in rechargeable batteries, which need to be explored under dynamic operating conditions. In this work, both planar and san... The formation of solid electrolyte interphase(SEI) and ion intercalation are two key processes in rechargeable batteries, which need to be explored under dynamic operating conditions. In this work, both planar and sandwich model lithium batteries consisting of Li metal | ionic liquid electrolyte | graphite electrode have been constructed and investigated by a series of in situ surface analysis platforms including atomic force microscopy, Raman and X-ray photoelectron spectroscopy. It is found that the choice of electrolyte, including the concentration and contents, has a profound effect on the SEI formation and evolution, and the subsequent ion intercalation. A smooth and compact SEI is preferably produced in highconcentration electrolytes, with FSI^(-) salt superior to TFSI^(-) salt, facilitating the lithiation/delithiation to achieve high capacity and excellent cycle stability, while suppressing the co-intercalation of electrolyte solvent ions. The innovative research scenario of well-defined model batteries in combination with multiple genuinely in situ surface analysis methods presented herein leads to insightful results, which provide valuable strategies for the rational design and optimization of practical batteries, and energy storage devices in general. 展开更多
关键词 Lithium ion batteries solid electrolyte interphase Ion intercalation In situ surface characterization Ionic liquid electrolyte
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Geophysical Investigation of a Solid Waste Disposal Site Using Integrated Electrical Resistivity Tomography and Multichannel Analyses of Surface Waves Methods 被引量:1
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作者 Ruobai Zhao Neil Anderson Jing Sun 《Journal of Geoscience and Environment Protection》 2020年第3期55-69,共15页
Electrical resistivity tomography survey was deployed at a solid waste landfill in southwest Missouri USA with the intent to map variations in moisture content through the solid waste and underlying subsurface, and to... Electrical resistivity tomography survey was deployed at a solid waste landfill in southwest Missouri USA with the intent to map variations in moisture content through the solid waste and underlying subsurface, and to map the top of bedrock. Multichannel analyses of surface waves survey was also deployed to map variations in engineering properties of the solid waste and underlying subsurface, and to constrain the interpretations of top of bedrock. The 2-D resistivity images through the waste suggest rainwater seeps through the cap cover system of the solid waste landfill, and moisture content within the solid waste increases with solid waste burial depth. The resistivity anomalies displayed by the soil and bedrock directly underneath the solid waste suggests a lateral component to moisture infiltrating at the toe of the landfill, which is flowing inward to the base of solid waste structural low. The 1-D shear wave velocity profiles obtained from the multichannel analyses of surface waves survey helped interpret the top of bedrock underneath the solid waste, where top of bedrock is difficult to map using electrical resistivity tomography, as shallow fractured bedrock is moist and displays comparable resistivity values to that of overlying soil. Not surprisingly, the top of bedrock is readily identified on the electrical resistivity tomography profiles in places where subsurface is relatively dry. The deployment of the combined non- invasive, cost and time effective geophysical surveys, along with engineering judgement on available site history data, has reasonably identified potential landfill seepage pathways. The methodology presented could be used in similar site investigation settings. 展开更多
关键词 ELECTRICAL RESISTIVITY Tomography ELECTRICAL RESISTIVITY Imaging MULTICHANNEL ANALYSES of surface Waves CCR solid Waste LANDFILL CCR LANDFILL ERT ERI MASW
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Immobilization of His-Tagged Proteins on Various Solid Surfaces Using NTA-Modified Chitosan 被引量:1
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作者 Masahiko Oshige Kazuhiro Yumoto +6 位作者 Hidefumi Miyata Shunsuke Takahashi Masaki Nakada Kanako Ito Miwa Tamegai Hiroki Kawaura Shinji Katsura 《Open Journal of Polymer Chemistry》 2013年第1期6-10,共5页
Continued advancement of protein array, bioelectrode, and biosensor technologies will necessitate development of methods that allow for increased protein immobilization capacity and more control over protein orientati... Continued advancement of protein array, bioelectrode, and biosensor technologies will necessitate development of methods that allow for increased protein immobilization capacity and more control over protein orientation. Toward these ends, we developed a method involving modification of chitosan with nitrilotriacetic acid (NTA) to achieve immobilization of a larger amount of His-tagged protein than is possible with current methods. The immobilization capacity of our method was evaluated using His-tagged GFP (Green Fluorescent Protein) as a model protein. The average immobilization density on modified glass was about 32 ng/mm2. Our method is suitable for use on a variety of solid surfaces, including glassy carbon, silicon wafers, polycarbonate, and beaten gold. 展开更多
关键词 Protein IMMOBILIZATION CHITOSAN Ni-NTA (Nickel-Nitrilotriacetic Acid) solid surface
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Improving the activity and stability of Ni-based electrodes for solid oxide cells through surface engineering:Recent progress and future perspectives 被引量:4
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作者 Junxian Pan Yongjian Ye +4 位作者 Mengzhen Zhou Xiang Sun Yihan Ling Keiji Yashiro Yan Chen 《Materials Reports(Energy)》 2021年第2期35-47,共13页
Solid oxide cells(SOCs)have attracted great attention in the past decades because of their high conversion efficiency,low environmental pollution and diversified fuel options.Nickel-based catalysts are the most widely... Solid oxide cells(SOCs)have attracted great attention in the past decades because of their high conversion efficiency,low environmental pollution and diversified fuel options.Nickel-based catalysts are the most widely used fuel electrode materials for SOCs due to the low price and high activity.However,when hydrocarbon fuels are employed,nickel-based electrodes face serious carbon deposition challenges,leading to a rapid decline of cell performance.Great efforts have been devoted to understanding the occurrence of the coking reaction,and to improving the stability of the electrodes in hydrocarbon fuels.In this review,we summarize recent research progress of utilizing surface modification to improve the stability and activity of Ni-based electrodes for SOCs by preventing carbon coking.The review starts with a briefly introduction about the reaction mechanism of carbon deposition,followed by listing several surface modification technologies and their working principles.Then we introduce representative works using surface modification strategies to prevent carbon coking on Ni-based electrodes.Finally,we highlight future direction of improving electrode catalytic activity and anti-coking performance through surface engineering. 展开更多
关键词 solid oxide cells Ni-based electrodes Carbon coking surface engineering
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AN APPROACH TO CALCULATE THE SURFACE TENSION OF THE LIQUID NITROGEN FILM ON SOLIDS FROM AN ADSORPTION ISOTHERM
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作者 陈晓立 顾金龙 秦世福 《Journal of China Textile University(English Edition)》 EI CAS 1996年第1期62-69,共8页
The equations, used in this paper to calculate the surface tension of the liquid nitrogen film formed by the physical adsorption on many different model solids (e.g. spherical partiele, plane particle and spherical ca... The equations, used in this paper to calculate the surface tension of the liquid nitrogen film formed by the physical adsorption on many different model solids (e.g. spherical partiele, plane particle and spherical cavity pores or cylindrical pores at the openings of both ends in solid bodies), have been derived on the thermodynamie principle. The calculated results have shown that the surface tension (γ) of the adsorbed liquid nitrogen film on most of non-porous solid surfaces diminishes with the rise of the nitrogen gas pressure (p) or of the adsorbed layers (n) at 77.3K; when p reaches the vapour pressure (p_s) of the bulk liquid nitrogen, y turns into the surface tension (γ_o) of the bulk liquid nitrogen; whgn p /p, 【0.98, there is an obvious difference between γ and γ_O. 展开更多
关键词 solid surface adsorption ISOTHERM liquid nitrogen FILM surface tension
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Finding Intersection Points of Curves and Surfaces for Solid Modeling in Curved-Surface Environment
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作者 王新龙 赵航 袁哲俊 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1997年第3期62-67,共6页
Intersecting is an important factor which influences the effociency androbustness of Boolean algorithms in solid modeling based on surved-surfaces,andintersecting algorithms are closely related to geometric representa... Intersecting is an important factor which influences the effociency androbustness of Boolean algorithms in solid modeling based on surved-surfaces,andintersecting algorithms are closely related to geometric representations of curved-surfaces.Although surfaces can be commonly represented with NURBS,unnecessary complexitiesare caused in the intersecting of quadric surfaces.Quadrics are frequently used to des-cribe geometric features of shafts,holes and grooves etc.in mechanical part designing,therefore;their intersection algorithms are required to have higher accuracy,higher efficiency and higher robustness.For this reason,a practical representation ofquadric surfaces is studied in detail,and on the basis of that,algorithms of intersectingpoints are developed between quadric suraces and their boundaies,i.e.,conics,quarticnonplanar space curves. 展开更多
关键词 Curved-surface intersecting QUADRIC surface solid modeling
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INVESTIGATION OF THE SOLID- SOLID SURFACE ADSORPTION OF Eu_2O_3 ON AMORPHOUS Al_2O_3
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作者 刘荣川 颜其洁 +4 位作者 翟亚 戚海华 夏元复 蒋建中 U Gonser 《Nuclear Science and Techniques》 SCIE CAS CSCD 1992年第2期107-111,共5页
Solid-solid surface adsorption of Eu2O3 on amorphous Al2O3 have been investigated by Mossbauer spectroscopy, X- ray diffraction analysis and laser Raman spectra (LRS). No X-ray diffraction peak of crystalline Eu2O3 ca... Solid-solid surface adsorption of Eu2O3 on amorphous Al2O3 have been investigated by Mossbauer spectroscopy, X- ray diffraction analysis and laser Raman spectra (LRS). No X-ray diffraction peak of crystalline Eu2O3 can be found for all samples studied. The LRS show that two peaks at 998 and 1051 cm-1 assigned to two-dimensional surface europium-oxygen species appear at Eu2O3 content of 18.7 wt%. The peak at 1068 cm-1 due to the surface species and another peak at 342cm-1 due to crystalline Eu2O3 content start to appear for the sample with an Eu2O3 content of 36.5 wt%. The dispersity of Eu2O3 on the surface of amorphous Al2O3 were compared with that of α-Al2O3,η-Al2O3 and SiO2 gel. The results of these studies indicate that the structure of Eu2O3 dispersed onto the support surface depend on the structure of support and that there is an inductive effect of support on the structure of the Eu2O3. 展开更多
关键词 MOSSBAUER spectroscopy XRD LRS EU2O3 AMORPHOUS Al2O3 solid- solid surface ADSORPTION
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Growth of Ga_xIn_(1-x)Sb Alloys by MOCVD Solid Composition Surface Morphology and Electrical Properties
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作者 张宝林 周天明 +1 位作者 宁永强 金亿鑫 《Rare Metals》 SCIE EI CAS CSCD 1995年第4期296-300,共5页
a.In-Sb alloys were grown on GaSb substrates by MOCVD at atmospheric pressure. TMGa, TMInand TMSb were used as reactants. Alloy solid competition , surface morphologies and electrical properties wereinvestigated. It... a.In-Sb alloys were grown on GaSb substrates by MOCVD at atmospheric pressure. TMGa, TMInand TMSb were used as reactants. Alloy solid competition , surface morphologies and electrical properties wereinvestigated. It was found that the growth temperature was a key parameter for optimized surface morphologyand crystalline quality of the Ga_zIn_1-Sb epilayers. The influence of growth temperature on the Ga solidcomposition was previously explained. The Ga solid composition was proportional to the Ga vapor compositionand vapor Ⅲ/V ratio, respectively . The Ga distribution as efficient was found to be 1. 22 under the optimizedgrowth parameters and decreased with decreasing growth temperature. The results of Hall measurements forGa.InSb alloys at room temperature show a P-type background doping. The hole mobility of the best samplewas 377 cm ̄2/V s with a hole concentration of 7. 6 x 10 ̄16 cm ̄(-3). 展开更多
关键词 MOCVD growth GalnSb solid composition surface morphology Electrieal properties
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Method of Precision Control of 3-D Solid Discretization Based on the Second-Order Osculating Surface
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作者 万小利 刘淑艳 +1 位作者 杨梦辰 汪虹 《Journal of Beijing Institute of Technology》 EI CAS 2003年第2期183-185,共3页
A discretization precision control method based on the second order osculating surface is proposed. The discretization precision of 3 D solid is controlled according to the error between the discrete solid surface a... A discretization precision control method based on the second order osculating surface is proposed. The discretization precision of 3 D solid is controlled according to the error between the discrete solid surface and its second order osculating surface. The global maximal error has been gotten after analyzing all the extremums of the error function. It can be used in controlling and optimizing the discretization precision of 3 D solid in computer 3 D modeling and NC milling path generation. 展开更多
关键词 3-D solid DISCRETIZATION precision control osculating surface
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New Analytical Methodology for Sb(III) Traces Quantification as Emergent Contaminant in Drinks Packaged PET Samples by Solid Surface Fluorescence
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作者 Marí a C. Talio +5 位作者 Valentina Feresin Vanesa Muñ oz Mariano Acosta Liliana P. FernÁ ndez 《American Journal of Analytical Chemistry》 2019年第9期377-393,共17页
Emerging contaminants constitute a set of substances that are released into the environment for which regulations are currently not established for their environmental monitoring, being antimony one of them. A new met... Emerging contaminants constitute a set of substances that are released into the environment for which regulations are currently not established for their environmental monitoring, being antimony one of them. A new methodology for Sb(III) traces monitoring by solid surface fluorescence is proposed. The metal was complexed with alizarine (Az) as fluorosphore reagent in alcaline medium in presence of the bile salt sodium cholate. To isolate the analyte of matrix constituents, a preconcentration/separation strategy on filter paper was introduced prior to determination step. The solid surface fluorescence was measured λem = 450 nm and λexc = 363 nm using a solid sampler holder. Under optimal conditions, the limits of detection and quantification of proposed methodology were 0.08 and 0.24 μg·L-1, respectively, showing a linear range from 0.24 to 304.4 μg·L-1 with good sensitivity and adequate selectivity. It was applied to the Sb(III) traces determination present in drinking water and beverages samples packaged in polyethylene terephthalate (PET) bottles widely consumed in Argentina. The combination of a preconcentration step on common filter paper and the inherent sensitivity of photoluminescent methods have permitted to achieve sensitivity similar to atomic spectroscopies using a lower price instrument typical in control laboratories. Precision and accuracy were tested with excellent agreement. Results were truenessed by ETAAS with satisfactory concordance. 展开更多
关键词 Emerging Contaminants ANTIMONY TRACES Alizarine solid surface FLUORESCENCE Waters and Beverages
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