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隐性思想政治教育过程探析 被引量:28
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作者 白显良 《思想理论教育》 2007年第11期57-65,共9页
隐性思想政治教育作为思想政治教育的一种独特的存在类型,其实践过程既满足思想政治教育过程的一般规定性,又具有其自身独有的规定性。隐性思想政治教育过程,从教育者角度侧重于表现为一个"隐"过程,内涵"识隐"、&qu... 隐性思想政治教育作为思想政治教育的一种独特的存在类型,其实践过程既满足思想政治教育过程的一般规定性,又具有其自身独有的规定性。隐性思想政治教育过程,从教育者角度侧重于表现为一个"隐"过程,内涵"识隐"、"寓隐"、"践隐"等环节;从受教育者角度则侧重于表现为一个"显"过程,内涵"经验感知"、"体验体认"、"实践外化"等环节。这种"隐"过程与"显"过程的区分是相对的,不是绝对的,并且两者就其实质而言是一个过程的两个方面,彼此辩证统一,构成一个有机的整体,而并不构成彼此独立的两个过程。 展开更多
关键词 隐性思想政治教育 ""过程 "隐"过程
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RESEARCH OF VOXELIZATION PROCESS IN SWEPT-VOLUME TECHNIQUE 被引量:2
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作者 姜太平 沈春林 +1 位作者 何亦征 王金岩 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第1期24-30,共7页
Now the image display techniques have made great progress. The planar display and a fully new true 3-D volumetric display technique are rapidly researched and come into the application. A method based on the voxel mak... Now the image display techniques have made great progress. The planar display and a fully new true 3-D volumetric display technique are rapidly researched and come into the application. A method based on the voxel makes the observer able to get a true 3-D effect freely without any additional facilities. This paper introduces the basic form of the swept-volume display technique and discusses its voxelization process. By the translational motion prototype, this paper emphasizes how to get the voxel mapping matrix. The translated image data are the data of the beam source deflections. Finally the voxel ordering and the optimizing are also discussed. 展开更多
关键词 voxelization process swept-volume voxel ordering
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Influence of thermomechanical processing on microstructure,texture evolution and mechanical properties of Al-Mg-Si-Cu alloy sheets 被引量:3
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作者 汪小锋 郭明星 +3 位作者 曹零勇 罗晋如 张济山 庄林忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第6期1752-1762,共11页
Influence of thermomechanical processing on the microstructure, texture evolution and mechanical properties of A1-Mg-Si-Cu alloy sheets was studied systematically. The quite weak mechanical properties anisotropy was o... Influence of thermomechanical processing on the microstructure, texture evolution and mechanical properties of A1-Mg-Si-Cu alloy sheets was studied systematically. The quite weak mechanical properties anisotropy was obtained in the alloy sheet through thermomechanical processing optimizing. The highly elongated microstmcture is the main structure for the hot or cold-rolled alloy sheets. H {001 } (110) and E { 111 } (110) are the main texture components in the surface layer of hot-rolled sheet, while ]/-fibre is dominant in quarter and center layers. Compared with the hot-rolled sheet, the intensities offl-fibre components are higher after the first cold rolling, but H {001 }(110) component in the surface layer decreases greatly. Almost no deformation texatre can be observed after intermediate annealing. And fl-fibre becomes the main texture again after the final cold rolling. With the reduction of the thickness, the through-thickness texture gradients become much weaker. The through-thickness recrystallization texture in the solution treated sample only has cubeyD {001 }(310) component. The relationship among thermomechanical processing, microstructure, texture and mechanical orouerties was analyzed. 展开更多
关键词 Ai-Mg-Si-Cu alloy therrnomechanical processing FORMABILITY MICROSTRUCTURE texture
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Taper barrel rheomoulding process for semi-solid slurry preparation and microstructure evolution of A356 aluminum alloy 被引量:5
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作者 张帆 康永林 +1 位作者 杨柳青 丁瑞华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第9期1677-1684,共8页
The self-developed taper barrel rheomoulding (TBR) machine for light alloy semi-solid slurry preparation was introduced.The semi-solid slurry was obtained from the intense shearing turbulence of the alloy melt in the ... The self-developed taper barrel rheomoulding (TBR) machine for light alloy semi-solid slurry preparation was introduced.The semi-solid slurry was obtained from the intense shearing turbulence of the alloy melt in the cause of solidification, which was further caused by the relative rotation of the internal and external taper barrel whose surface contained wale and groove.The heat transmission model of TBR process, the flow rules and the shearing model of the alloy melt were deduced.Taking A365 as experimental material, the microstructure evolution rules under different slurry preparation processes were analyzed.The results show that decreasing the pouring temperature of A365 alloy melt properly or increasing the shearing rate helps to obtain ideal semi-solid microstructure with the primary particle size of about 70 μm and the shape factor of above 0.8. 展开更多
关键词 taper barrel rheomoulding semi-solid slurry preparation microstrncture evolution A356 aluminum alloy
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Corrosion Process Detection of Tinplate in Deaerated Functional Beverage by EIS 被引量:2
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作者 王吉会 付丛伟 +1 位作者 高志明 夏大海 《Transactions of Tianjin University》 EI CAS 2013年第4期235-240,共6页
The corrosion process of tinplate in deaerated functional beverage was investigated by using electrochemical impedance spectroscopy (EIS) combined with scanning electron microscopy (SEM) and energy dispersive spectros... The corrosion process of tinplate in deaerated functional beverage was investigated by using electrochemical impedance spectroscopy (EIS) combined with scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) techniques. The results reveal that the uncoated tinplate shows a poor corrosion resistance and the corrosion type is detinning. During the initial stage of immersion, EIS spectrum consisted of two capacitance arcs with obvious time-constant dispersion effect, which was attributed to the two-dimensional and three-dimensional inhomogeneous distribution of the electrode surface. With the increase of immersion time, the capacitance arc of high frequency shrunk and degenerated, due to the corrosion of tin coating. The pore resistance of tin coating and the charger transfer resistance of substrate, which are determined from the electrochemical equivalent circuit, can be used as the indicators of tinplate corrosion process. The decrease of the pore resistance of tin coating indicates that the corrosion degree of tin layer becomes more severe, whereas the decrease of the charger transfer resistance of substrate implies that the corrosion degree of steel substrate also becomes more severe as the immersion time prolongs. 展开更多
关键词 electrochemical impedance spectroscopy TINPLATE functional beverage corrosion process deaerated condition
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The adsorptive properties of UiO-66 towards organic dyes: A record adsorption capacity for the anionic dye Alizarin Red S. 被引量:11
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作者 Marwa S.Embaby Saber D.Elwany +1 位作者 Widiastuti Setyaningsih Mohamed R.Saber 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第4期731-739,共9页
In order to decisively determine the adsorption selectivity of zirconium MOF(UiO-66) towards anionic versus cationic species, the adsorptive removal of the anionic dyes(Alizarin Red S.(ARS), Eosin(E), Fuchsin Acid(FA)... In order to decisively determine the adsorption selectivity of zirconium MOF(UiO-66) towards anionic versus cationic species, the adsorptive removal of the anionic dyes(Alizarin Red S.(ARS), Eosin(E), Fuchsin Acid(FA)and Methyl Orange(MO)) and the cationic dyes(Neutral Red(NR), Fuchsin Basic(FB), Methylene Blue(MB),and Safranine T(ST)) has been evaluated. The results clearly reveal a significant selectivity towards anionic dyes. Such an observation agrees with a plethora of reports of UiO-66 superior affinity towards other anionic species(Floride, PO_4^(3-), Diclofenac sodium, Methylchlorophenoxy-propionic acid, Phenols, CrO_4^(2-), SeO_3^(2-), and AsO_4^-). The adsorption process of ARS as an example has been optimized using the central composite design(CCD). The resultant statistical model indicates a crucial effect of both pH and sorbent mass. The optimum conditions were determined to be initial dye concentration 11.82 mg.L^(-1), adsorbent amount 0.0248 g, shaking time of 36 min and pH 2. The adsorption process proceeds via pseudo-second order kinetics(R^2= 0.999). The equilibrium data were fit to Langmuir and Tempkin models(R^2= 0.999 and 0.997 respectively). The results reveal an exceptional removal for the anionic dye(Alizarin Red S.) with a record adsorption capacity of400 mg·g^(-1). The significantly high adsorption capacity of UiO-66 towards ARS adds further evidence to the recently reported exceptional performance of MOFs in pollutants removal from water. 展开更多
关键词 Adsorption Metal-organic frameworks Alizarin Red S. Dye removal UiO-66 Central composite design
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Observation on Double Fertilization and Early Embryonic Development in Autotetraploid Polyembryonic Rice 被引量:2
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作者 DAI Xi-mei YANG Xu HUANG Qun-ce QIN Guang-yong 《Rice science》 SCIE 2009年第2期124-130,共7页
The process of double fertilization and the characters of embryo and endosperm development in an autotetraploid polyembryonic mutant rice IR36-Shuang were studied with a laser scanning confocal microscopy. Some abnorm... The process of double fertilization and the characters of embryo and endosperm development in an autotetraploid polyembryonic mutant rice IR36-Shuang were studied with a laser scanning confocal microscopy. Some abnormalities including degenerated ovary, abortive embryo sac, single fertilization, double-ovule and double-embryo and so on. were found dudng double fertilization and embryo development in IR36-Shuang. The rate of the abnormalities was 46.67% in IR36-Shuang, significantly higher than that in the control, an autotetraploid rice line IR36-4X (33.00%). Cytological and embryonic evidences were provided for seed setting decline and the initiation of additional embryo in IR36-Shuang. 展开更多
关键词 RICE autotetraploid polyembryony double fertilization reproductive developmental character developmental biology embryonic development
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Corrosion behavior of 907 steel under thin electrolyte layers of artificial seawater 被引量:7
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作者 王慧萍 丁少春 +3 位作者 朱娟 张昭 张鉴清 曹楚南 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第3期806-814,共9页
The corrosion behavior of 907 steel under thin electrolyte layer(TEL) has been investigated by means of cathodic polarization curve measurement, electrochemical impedance spectroscopy(EIS) and scanning electron micros... The corrosion behavior of 907 steel under thin electrolyte layer(TEL) has been investigated by means of cathodic polarization curve measurement, electrochemical impedance spectroscopy(EIS) and scanning electron microscopy(SEM). The results show that the cathodic diffusion current density presents the variation trend of initial increase and subsequent decrease with the decrease of TEL thickness, and the maximum deposits at 58 μm. The cotangent-hyperbolic impedance(O) is rationally first introduced to study the diffusion process of the reactants through the corrosion products layer with many permeable holes. The initial corrosion rate of 907 steel under different TEL thickness increases with the decrease of TEL thickness except that of 104 μm,whereas the corrosion rate after long time corrosion can be ranked as 104 μm﹥402 μm﹥198 μm﹥301 μm﹥bulk solution. 展开更多
关键词 907 steel atmospheric corrosion electrochemical impedance spectroscopy polarization
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Damage mechanism of single-layer reticulated domes under severe earthquakes 被引量:1
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作者 于晓野 范峰 +1 位作者 支旭东 沈世钊 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2009年第1期121-130,共10页
To study the damage mechanism of single-layer reticulated domes subject to severe earthquakes, three limit states of single-layer reticulated domes under earthquakes are defined firstly in this paper. Then, two failur... To study the damage mechanism of single-layer reticulated domes subject to severe earthquakes, three limit states of single-layer reticulated domes under earthquakes are defined firstly in this paper. Then, two failure modes are presented by analyzing damage behaviors, and their characteristics are pointed out respectively. Furthermore, the damage process is analyzed and the causes of structural damage in different levels are studied. Finally, by comparing deformation and vibration status of domes with different failure modes, the principles of different failures are revealed and an integrated frame of damage mechanism is set up. 展开更多
关键词 single-layer reticulated domes severe earthquakes damage mechanism limit states failure modes
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Investigation of Improved Signal Process and Control Circuit for Color-PDP
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作者 邱崧 仇润鹤 +2 位作者 胡文静 张天桥 李煌 《Journal of Donghua University(English Edition)》 EI CAS 2007年第1期94-98,共5页
We present an alternative current-plasma display panel (AC-PDP) signal process and control circuit that fulfills the signal process and transform function. We proposed a novel driving logical waveform generator based ... We present an alternative current-plasma display panel (AC-PDP) signal process and control circuit that fulfills the signal process and transform function. We proposed a novel driving logical waveform generator based on the SCI interface, which can real-time adjust the parameters to optimize performance of the PDP and facilitate the research and test. The use of nesting state-machine and parameterized design not only improves the resource utilization, but also makes it efficient and readable. The design has been written in synthesizable Verilog and fully verified using Xilinx FPGA device and applied in 42-in AC-PDP module. 展开更多
关键词 AC-PDP VERILOG SCI interface FPGA nesting State-Machine.
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Study of Biofilm Formed by Lactic Acid Bacteria on the Surface of Mild Steel 被引量:1
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作者 Tsveteslava Veselinova Ignatova-Ivanova Radoslav Iliev Ivanov 《Journal of Life Sciences》 2014年第10期799-804,共6页
Biocorrosion processes at metal surfaces are associated with microorganisms, or the products of their metabolic activities including enzymes, exopolymers, organic and inorganic acids, as well as volatile compounds suc... Biocorrosion processes at metal surfaces are associated with microorganisms, or the products of their metabolic activities including enzymes, exopolymers, organic and inorganic acids, as well as volatile compounds such as ammonia or hydrogen sulfde. It was proved that strain Lactobacillus delbrueckii B5 constituted biofilms in the presence of different amounts of carbohydrates (5% sucrose and a mixture of 5% lactose, 5% fructose and 5% maltose). The obtained information was used in a study treating the anticorrosive properties of microbial biofilms synthesized by the latter strain. The study of the corrosive stability of steel samples was conducted on the gravimetrique method. The rate of corrosion, calculated. The structure of layer over steel plates was analyzed by the degree of protection, and coefficient of protection has been Scanning Electron Microscopy (SEM) JSM 5510. 展开更多
关键词 BIOFILM CORROSION INHIBITOR lactic acid bacteria SEM.
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Growth process and corrosion resistance of micro-arc oxidation coating on Mg-Zn-Gd magnesium alloys 被引量:6
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作者 王萍 刘道新 +2 位作者 李建平 郭永春 杨忠 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第11期2198-2203,共6页
A Mg-6Zn-3Gd(mass fraction,%) alloy,noted as ZG63,was coated by different micro-arc oxidation(MAO) processes,and the coating structure and corrosion resistance of the alloy were studied using scanning electron microsc... A Mg-6Zn-3Gd(mass fraction,%) alloy,noted as ZG63,was coated by different micro-arc oxidation(MAO) processes,and the coating structure and corrosion resistance of the alloy were studied using scanning electron microscopy(SEM),glancing angle X-ray diffractometry(GAXRD) and various electrochemical methods.The micro-arc oxidation process consists of three stages and corresponds with different coating structures.In the initial stage,the coating thickness is linearly increased and is controlled by electrochemical polarization.In the second stage,the coating grows mainly inward and accords with parabolic regularity.In the third stage,the loose coating forms and is controlled by local arc light.The looser coating is mainly composed of MgSiO3 and the compact coating is mainly composed of MgO.From micro-arc oxidation stage to local arc light stage,the corrosion resistance of the coated alloy firstly increases and then decreases.The satisfied corrosion resistance corresponds to the coating time ranging from 6 to10 min. 展开更多
关键词 Mg-6Zn-3Gd magnesium alloys micro-arc oxidation growth process corrosion resistance
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Formation and evolution of Emeishan basalt saprolite in vadose zones of Touzhai landslide source rockmass 被引量:1
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作者 YANG Ji-qing XU Ze-min +4 位作者 ZHANG Rui CHEN Ji-pu REN Zhe LUO Rong-zhang ZHANG Xiu-shuo 《Journal of Mountain Science》 SCIE CSCD 2017年第6期1174-1184,共11页
In order to explain the formation process of slope hazards, and to identify the key factors leading to instability of a slope, Emeishan basalt saprolite in vadose zones of the Touzhai landslide in Zhaotong, Yunnan, wa... In order to explain the formation process of slope hazards, and to identify the key factors leading to instability of a slope, Emeishan basalt saprolite in vadose zones of the Touzhai landslide in Zhaotong, Yunnan, was studied. The formation and evolution of Emeishan basalt saprolite was examined using, amongst other techniques, field investigations,thin section analysis, scanning electron microscopy(SEM) observations, chemical analysis, physical and water-physical property tests of rock masses. Field observations revealed that the majority of the weathered rock blocks were presented as a concentric layer structure in which an internal corestone was enveloped with several layers of external saprolized crust. Chemical and mineralogical analysis identified that iron was the most sensitive element and that the weathering progress usually started with the oxidation of Fe2+ to Fe3+ in rock blocks. Alkaline elements such as Si, Ca, Mg, Na and K were also dissolved and Fe and Al were concentrated in saprolized crusts. Results indicated that loss on ignition(LOI) also increased significantly. SEM results showed that the weathering intensity of thebasalt blocks decreased gradually from the outside to the inside, and the mineral morphology significantly differed on both sides of the weathering front. The saprolized crusts presented cellular microstructure features due to the generation of micropore and clay minerals. Thin section analysis showed that plagioclase was relatively more stable than pyroxene and chlorite during weathering. With a centripetal propagation of the weathering front, saprolized crusts became thicker and corestones became smaller; fresh Emeishan basalt blocks gradually turned into saprolized blocks. Due to the loose structure and low strength of saprolite, the quality of the Emeishan basalt mass significantly deteriorated, this being a potentially important factor which caused the Touzhai landslide to occur. 展开更多
关键词 Vadose zone Emeishan basalt Scanning electron microscopy Saprolite Corestone Touzhai landslide
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Precipitation processes and luminescence properties of ZnO:La^(3+), Li^+ nanoparticles 被引量:2
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作者 古映莹 李陆柯 +2 位作者 张稳稳 刘英 卢周广 《Journal of Central South University》 SCIE EI CAS 2013年第2期332-336,共5页
ZnO:La3+,Li+ nanoparticles were successfully prepared by co-precipitation, citric acid-assisted co-precipitation, co-precipitation combined solid-state reaction and thermal decomposition method. X-ray diffraction ... ZnO:La3+,Li+ nanoparticles were successfully prepared by co-precipitation, citric acid-assisted co-precipitation, co-precipitation combined solid-state reaction and thermal decomposition method. X-ray diffraction (XRD), scanning electron microscopy (SEM) and luminescence spectrophotometry were employed to characterize the crystal phases, particle sizes and luminescence properties of the as-prepared nanopowders. The results indicate that all the prepared samples crystallize in a hexagonal wurtzite structure. The ZnO:La3+,Li+ prepared by citric acid-assisted co-precipitation method has a particle size of about 80 nm, which is the smallest among all the samples. Fluorescence (FL) spectra of all samples exhibit three typical emissions: a violet one centered at around 400 nm, blue around 450 nm and 466 rim, and weak green near 520 nm. But the samples prepared by co-precipitation method show a strong and wide green light emission located at about 500 nm. The ZnO:La3+,Li+ nanoparticles synthesized by the co-precipitation method demonstrate relatively the strongest emission intensity. 展开更多
关键词 ZNO La3+ Li+ -Key words: ZnO:La L1 nanopartxcles doping co-precipitation method luminescence properties
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Anodic passivation of Pb-Ag-Nd anode in fluoride-containing H_2SO_4 solution 被引量:1
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作者 钟晓聪 蒋良兴 +2 位作者 刘芳洋 李劼 刘业翔 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期2894-2901,共8页
An attempt was made to build up a thick and compact oxide layer rapidly by pre-treating the Pb-Ag-Nd anode in fluoride-containing H2SO4 solution. The passivation reaction of Pb-Ag-Nd anode during pre-treatment process... An attempt was made to build up a thick and compact oxide layer rapidly by pre-treating the Pb-Ag-Nd anode in fluoride-containing H2SO4 solution. The passivation reaction of Pb-Ag-Nd anode during pre-treatment process was investigated using cyclic voltammetry, linear scanning voltammetry, environmental scanning electron microscopy and X-ray diffraction analysis. The results show that Pb F2 and PbSO4 are formed near the potential of Pb/PbSO4 couple. The pre-treatment in fluoride-containing H2SO4 solution contributes to the formation of a thick, compact and adherent passive film. Furthermore, pre-treatment in fluoride-containing H2SO4 solution also facilitates the formation of PbO2 on the anodic layer, and the reason could be attributed to the formation of more PbF2 and PbSO4 during the pre-treatment which tend to transform to PbO2 during the following electrowinning process. In addition, the anodic layer on anode with pre-treatment in fluoride-containing H2SO4 solution is thick and compact, and its predominant composition is β-PbO2. In summary, the pre-treatment in fluoride-containing H2SO4 solution benefits the formation of a desirable protective layer in a short time. 展开更多
关键词 lead-based anode FLUORIDE passive film anodic layer synergistic effect
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Preparation of basic magnesium carbonate and its thermal decomposition kinetics in air 被引量:2
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作者 刘欣伟 冯雅丽 李浩然 《Journal of Central South University》 SCIE EI CAS 2011年第6期1865-1870,共6页
The thermal decomposition process of basic magnesium carbonate was investigated. Firstly, Basic magnesium carbonate was prepared from magnesite, and the characteristics of the product were detected by X-ray diffracti... The thermal decomposition process of basic magnesium carbonate was investigated. Firstly, Basic magnesium carbonate was prepared from magnesite, and the characteristics of the product were detected by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Subsequently, the thermal decomposition process of basic magnesium carbonate in air was studied by thermogravimetry-differential thermogravimetry (TG-DTG). The results of XRD confirm that the chemical composition of basic magnesium carbonate is 4MgCO3·Mg(OH)2·4H2O. And the SEM images show that the sample is in sheet structure, with a diameter of 0.1-1 μm. The TG-DTG results demonstrate that there are two steps in the thermal decomposition process of basic magnesium carbonate. The apparent activation energies (E) were calculated by Flyrm-Wall-Ozawa method. It is obtained from Coats-Redfem's equation and Malek method that the mechanism functions of the two decomposition stages are D3 and A1.5, respectively. And then, the kinetic equations of the two steps were deduced as well. 展开更多
关键词 basic magnesium carbonate TG-DTG thermal decomposition KINETICS mechanism function
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Contrastive analysis of prefix dis- and un- in English
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作者 李集团 《International English Education Research》 2014年第5期89-91,共3页
English prefix dis- and tin- are commonly surveyed along with some other negative prefixes. However, there are many cases in which prefix dis- and un- can be attached to the same root, causing the difficulty in distin... English prefix dis- and tin- are commonly surveyed along with some other negative prefixes. However, there are many cases in which prefix dis- and un- can be attached to the same root, causing the difficulty in distinguishing the comprehension of the two prefixes' semantic roles. Considering this issue, this paper endeavors to clarify the respective morphological processes and explain their specific semantic roles. 展开更多
关键词 dis- un- morphological process semantic role
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Microstructural characteristics of near-liquidus cast AZ91D alloy during semi-solid die casting 被引量:8
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作者 王开 刘昌明 +1 位作者 翟彦博 邹茂华 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第2期171-177,共7页
Near-liquidus cast ingot was reheated to semi-solid firstly, and then a bracket of motor was prepared by die casting the semi-solid ingot into mould. The microstructural characteristics of AZ91D alloy in these process... Near-liquidus cast ingot was reheated to semi-solid firstly, and then a bracket of motor was prepared by die casting the semi-solid ingot into mould. The microstructural characteristics of AZ91D alloy in these processes were investigated. In the process of near-liquidus casting, primary α-Mg grains tend to be rosette-like because of the increase of plentiful quasi-solid atom clusters in molten alloy with the decrease of pouring temperature. These rosette-like a-Mg grains in ingots fabricated by near-liquidus casting are fused off and refined into near-globular structure owing to the solute diffusion mechanism and the minimum surface energy mechanism during reheating. After semi-solid die-casting, a-Mg grains, located in biscuit, impact and connect with each other; α-Mg grains, located in inner gate, congregate together; while α-Mg grains, located in component, distribute uniformly and become into globularity or strip. Because the inner gate limits the flowing of semi-solid slurry, and the pressure acted on the semi-solid slurry decreases gradually along the filling direction of semi-solid slurry in Cavity, microstructural segregation of unmelted a-Mg grains appears along this direction. Shrinkage holes in casting are caused by two different reasons. For biscuit, the shrinkage holes are caused by the blocked access of feeding liquid to the shrinkage zone for the agglomerated unmelted α-Mg grains. For component, the shrinkage holes are caused by the lack of feeding of liquid alloy. 展开更多
关键词 AZ91D magnesium alloy MICROSTRUCTURE semi-solid die casting process MORPHOLOGY
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Morphological variation and distribution of free neuromasts during half-smooth tongue sole Cynoglossus semilaevis ontogeny
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作者 马爱军 商晓梅 +5 位作者 周洲 王新安 孙志宾 崔文晓 夏丹丹 马本贺 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第2期244-250,共7页
This study was conducted to clarify the distribution and morphology of free neuromasts during the development of half-smooth tongue sole (Cynoglossus semilaevis) using scanning electron microscopy. During developmen... This study was conducted to clarify the distribution and morphology of free neuromasts during the development of half-smooth tongue sole (Cynoglossus semilaevis) using scanning electron microscopy. During development, (1) the apical surface of free neuromasts changed in shape from a circle to a four-poiut star; (2) the external structure changed from being level with the epidermis to papilla-like above the level of the epidermis; (3) the neuromast cupula changed from cylindrical to blade-shaped; (4) the free neuromasts went from occurring singly to being in clusters of a few single organs; (5) the arrangement changed from a linear array to no discernable pattern; (6) there was a significant increase in the number of free neuromasts after metamorphosis. In adult C. semilaevis, free neuromasts were only observed on the abocular side of the head. Thus, there were more free neuromasts located on the abocular side of the head with a higher concentration around the anterior nostril and mouth, which may have a mechanical sensory function to help locate food as an adaptation to a benthic mode of life. 展开更多
关键词 MORPHOLOGY structure cupula METAMORPHOSIS scanning electron microscopy (SEM)
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Microstructure Evolution at Different Cooling Rates of Low Carbon Microalloyed Steels
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作者 Elena Brandaleze Matias Ramirez Martina Avalos 《Journal of Chemistry and Chemical Engineering》 2017年第1期22-29,共8页
In low carbon microalloyed steels (C 〈 0.1%), the content of V, Nb and Ti affects the phases transformation kinetic during cooling in the rolling process. The final microstructure determines the required mechanical... In low carbon microalloyed steels (C 〈 0.1%), the content of V, Nb and Ti affects the phases transformation kinetic during cooling in the rolling process. The final microstructure determines the required mechanical properties such as high formability, high toughness and adequate strength. For this reason it is relevant to identify and determine the volume fraction of the ferrite, bainite and martensite present in the structure. The microalloying elements: V, Nb and Ti promote carbides precipitation during cooling. The precipitates control the grain size refinement during hot rolling process and the mechanical properties of the steel. In this sense it is necessary to increase the knowledge on the microstructure evolution at different cooling rates. In this paper, the results obtained on two low carbon microalloyed steels (with C contents between 0.11%-0.06%) are reported. An integrated methodology including dilatometry in combination with microscopy techniques was applied. By EBSD (Electron Backscatter Diffraction) technique and microhardness measurements, the structural study was completed. Through a thermodynamic simulation using Fact Sage the type of precipitates in the studied steels structure at the temperature range between 950 ℃ and 450 ℃, were predicted. The information on the evolution of the steel structure at rolling process conditions is relevant to consider changes in processing conditions. 展开更多
关键词 Low carbon steels dilatometry cooling curves phases transformation precipitates.
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