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Digital measuring the ocular morphological parameters of guinea pig eye in vivo with Python
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作者 Yue Di Zhong-Bao Qiao +4 位作者 Hai-Yun Ye Xin-Yue Li Wen-Ting Luo Wang-Yi Fang Tong Qiao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第2期239-246,共8页
AIM:To quantitatively measure ocular morphological parameters of guinea pig with Python technology.METHODS:Thirty-six eyeballs of eighteen 3-weekold guinea pigs were measured with keratometer and photographed to obtai... AIM:To quantitatively measure ocular morphological parameters of guinea pig with Python technology.METHODS:Thirty-six eyeballs of eighteen 3-weekold guinea pigs were measured with keratometer and photographed to obtain the horizontal,coronal,and sagittal planes respectively.The corresponding photo pixels-actual length ratio was acquired by a proportional scale.The edge coordinates were identified artificially by ginput function.Circle and conic curve fitting were applied to fit the contour of the eyeball in the sagittal,coronal and horizontal view.The curvature,curvature radius,eccentricity,tilt angle,corneal diameter,and binocular separation angle were calculated according to the geometric principles.Next,the eyeballs were removed,canny edge detection was applied to identify the contour of eyeball in vitro.The results were compared between in vivo and in vitro.RESULTS:Regarding the corneal curvature and curvature radius on the horizontal and sagittal planes,no significant differences were observed among results in vivo,in vitro,and the keratometer.The horizontal and vertical binocular separation angles were 130.6°±6.39°and 129.8°±9.58°respectively.For the corneal curvature radius and eccentricity in vivo,significant differences were observed between horizontal and vertical planes.CONCLUSION:The Graphical interface window of Python makes up the deficiency of edge detection,which requires too much definition in Matlab.There are significant differences between guinea pig and human beings,such as exotropic eye position,oblique oval eyeball,and obvious discrepancy of binoculus.This study helps evaluate objectively the ocular morphological parameters of small experimental animals in emmetropization research. 展开更多
关键词 ocular morphological parameters guinea pig digital measurement PYTHON
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Optimization of AZ80 magnesium alloy squeeze cast process parameters using morphological matrix 被引量:6
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作者 郭志宏 侯华 +1 位作者 赵宇宏 屈淑维 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第2期411-418,共8页
The squeeze cast process parameters of AZ80 magnesium alloy were optimized by morphological matrix. Experiments were conducted by varying squeeze pressure, die pre-heat temperature and pressure duration using L9(33)... The squeeze cast process parameters of AZ80 magnesium alloy were optimized by morphological matrix. Experiments were conducted by varying squeeze pressure, die pre-heat temperature and pressure duration using L9(33) orthogonal array of Taguchi method. In Taguchi method, a 3-level orthogonal array was used to determine the signal/noise ratio. Analysis of variance was used to determine the most significant process parameters affecting the mechanical properties. Mechanical properties such as ultimate tensile strength, elongation and hardness of the components were ascertained using multi variable linear regression analysis. Optimal squeeze cast process parameters were obtained. 展开更多
关键词 AZ80 magnesium alloy squeeze cast process parameters morphological matrix OPTIMIZATION
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Effect of process parameters on the morphology of aluminum/copper alloy lap joints by red and blue hybrid laser welding
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作者 宋曜祥 肖梦智 +4 位作者 黄德才 张瑞华 尹燕 茹恩光 吴怡霖 《China Welding》 CAS 2024年第2期23-30,共8页
In order to overcome the problems of many pores,large deformation and unstable weld quality of traditional laser welded aluminumcopper alloy joints,a red-blue dual-beam laser source and a swinging laser were introduce... In order to overcome the problems of many pores,large deformation and unstable weld quality of traditional laser welded aluminumcopper alloy joints,a red-blue dual-beam laser source and a swinging laser were introduced for welding.T2 copper and 6063 aluminum thin plates were lap welded by coaxial dual-beam laser welding.The morphology of weld cross section was compared to explore the influence of process parameters on the formation of lap joints.The microstructure characteristics of the weld zone were observed and compared by optical microscope.The results show that the addition of laser beam swing can eliminate the internal pores of the weld.With the increase of the swing width,the weld depth decreases,and the weld width increases first and then decreases.The influence of welding speed on the weld cross section morphology is similar to that of swing width.With the increase of welding speed,the weld width increases first and then decreases,while the weld depth decreases all the time.This is because that the red laser is used as the main heat source to melt the base metals,with the increase of red laser power,the weld depth increases.As an auxiliary laser source,blue laser reduces the total energy consumption,consequently,the effective heat input increases and the spatter is restrained effectively.As a result,the increase of red laser power has an enhancement effect on the weld width and weld depth.When the swing width is 1.2 mm,the red laser power is 550 W,the blue laser power is 500 W,and the welding speed is 35 mm/s,the weld forming is the best.The lap joint of T2 copper and 6063 aluminum alloy thin plate can be connected stably with the hybrid of blue laser.The effect rules of laser beam swing on the weld formation were obtained,which improved the quality of the joints. 展开更多
关键词 laser welding aluminum/copper alloy dual beam process parameters weld morphology
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Three-dimensional(3D)parametric measurements of individual gravels in the Gobi region using point cloud technique
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作者 JING Xiangyu HUANG Weiyi KAN Jiangming 《Journal of Arid Land》 SCIE CSCD 2024年第4期500-517,共18页
Gobi spans a large area of China,surpassing the combined expanse of mobile dunes and semi-fixed dunes.Its presence significantly influences the movement of sand and dust.However,the complex origins and diverse materia... Gobi spans a large area of China,surpassing the combined expanse of mobile dunes and semi-fixed dunes.Its presence significantly influences the movement of sand and dust.However,the complex origins and diverse materials constituting the Gobi result in notable differences in saltation processes across various Gobi surfaces.It is challenging to describe these processes according to a uniform morphology.Therefore,it becomes imperative to articulate surface characteristics through parameters such as the three-dimensional(3D)size and shape of gravel.Collecting morphology information for Gobi gravels is essential for studying its genesis and sand saltation.To enhance the efficiency and information yield of gravel parameter measurements,this study conducted field experiments in the Gobi region across Dunhuang City,Guazhou County,and Yumen City(administrated by Jiuquan City),Gansu Province,China in March 2023.A research framework and methodology for measuring 3D parameters of gravel using point cloud were developed,alongside improved calculation formulas for 3D parameters including gravel grain size,volume,flatness,roundness,sphericity,and equivalent grain size.Leveraging multi-view geometry technology for 3D reconstruction allowed for establishing an optimal data acquisition scheme characterized by high point cloud reconstruction efficiency and clear quality.Additionally,the proposed methodology incorporated point cloud clustering,segmentation,and filtering techniques to isolate individual gravel point clouds.Advanced point cloud algorithms,including the Oriented Bounding Box(OBB),point cloud slicing method,and point cloud triangulation,were then deployed to calculate the 3D parameters of individual gravels.These systematic processes allow precise and detailed characterization of individual gravels.For gravel grain size and volume,the correlation coefficients between point cloud and manual measurements all exceeded 0.9000,confirming the feasibility of the proposed methodology for measuring 3D parameters of individual gravels.The proposed workflow yields accurate calculations of relevant parameters for Gobi gravels,providing essential data support for subsequent studies on Gobi environments. 展开更多
关键词 Gobi gravels three-dimensional(3D)parameters point cloud 3D reconstruction Random Sample Consensus(RANSAC)algorithm Density-Based Spatial Clustering of Applications with Noise(DBSCAN)
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Morphological properties and proliferation analysis of olfactory ensheathing cells seeded onto three-dimensional collagen-heparan sulfate biological scaffolds 被引量:2
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作者 Na Liu Zhouping Tang Zhiyuan Yu Minjie Xie Yu Zhang Erfang Yang Shabei Xu 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第16期1213-1219,共7页
This study aimed to examine the differences in the morphological properties and proliferation of olfactory ensheathing cells in three-dimensional culture on collagen-heparan sulfate biological scaffolds and in two-dim... This study aimed to examine the differences in the morphological properties and proliferation of olfactory ensheathing cells in three-dimensional culture on collagen-heparan sulfate biological scaffolds and in two-dimensional culture on common flat culture plates. The proliferation rate of olfactory ensheathing cells in three-dimensional culture was higher than that in two-dimensional culture, as detected by an M-I-r assay. In addition, more than half of the olfactory ensheathing cells subcultured using the trypsinization method in three-dimensional culture displayed a spindly Schwann cell-like morphology with extremely long processes, while they showed a flat astrocyte-like morphology in two-dimensional culture. Moreover, spindle-shaped olfactory ensheathing cells tended to adopt an elongated bipolar morphology under both culture conditions. Experimental findings indicate that the morphological properties and proliferation of olfactory ensheathing cells in three-dimensional culture on collagen-heparan sulfate biological scaffolds are better than those in two-dimensional culture. 展开更多
关键词 morphological properties cell proliferation biological scaffold olfactory ensheathing cells three-dimensional culture neural regeneration
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New criterion for rock joints based on three-dimensional roughness parameters 被引量:8
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作者 唐志成 刘泉声 黄继辉 《Journal of Central South University》 SCIE EI CAS 2014年第12期4653-4659,共7页
The shear behavior of rock joints is important in solving practical problems of rock mechanics. Three group rock joints with different morphologies are made by cement mortar material and a series of CNL(constant norma... The shear behavior of rock joints is important in solving practical problems of rock mechanics. Three group rock joints with different morphologies are made by cement mortar material and a series of CNL(constant normal loading) shear tests are performed. The influences of the applied normal stress and joint morphology to its shear strength are analyzed. According to the experimental results, the peak dilatancy angle of rock joint decreases with increasing normal stress, but increases with increasing roughness. The shear strength increases with the increasing normal stress and the roughness of rock joint. It is observed that the modes of failure of asperities are tensile, pure shear, or a combination of both. It is suggested that the three-dimensional roughness parameters and the tensile strength are the appropriate parameter for describing the shear strength criterion. A new peak shear criterion is proposed which can be used to predict peak shear strength of rock joints. All the used parameters can be easily obtained by performing tests. 展开更多
关键词 rock joint shear behavior peak shear strength three-dimensional roughness parameter
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Morphological parameters of both surfaces of coupled joint 被引量:1
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作者 范祥 曹平 +1 位作者 黄雪姣 陈瑜 《Journal of Central South University》 SCIE EI CAS 2013年第3期776-785,共10页
Twenty one joints were made with Brazilian tests and each surface was scanned by the Talysurf CLI 2000. Morphological characteristics of joint surface were quantified by statistical and textural parameters. By the con... Twenty one joints were made with Brazilian tests and each surface was scanned by the Talysurf CLI 2000. Morphological characteristics of joint surface were quantified by statistical and textural parameters. By the contrast of these parameters between both sides of each coupled joint, the following conclusions are drawn. The upper and lower surfaces of coupled joints have approximately equal values of Sp(maximum height of joint surface), Sa(arithmetic mean height of joint surface) and Sq(root mean square height of joint surface), but the Ssk(skewness of the height distribution of joint surface) values of the two surfaces of a coupled joint are different, one is positive while the other is negative. The Saj(auto-correlation length) parameter values of both surfaces of each coupled joint are quite close, and the S^(texture aspect ratio) values have the same situation to the Sal parameter, but the same parameters of different surfaces have big differences which illustrates its own characteristics of each joint. The two surfaces of each coupled joint have similar values of θp (mean profile angle) which can be used to deduce the value of θp each other. 展开更多
关键词 coupled joint morphology statistical parameter textural parameter profile mean angle envelop area
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Effects of rigid gas permeable contact lens on morphological parameters and vision-related quality of life in keratoconus patients 被引量:2
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作者 Yue Xu Yun Wang Xiao-Feng Zhang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2022年第11期1772-1781,共10页
AIM: To evaluate the effect of rigid gas permeable contact lens(RGP-CL) on corneal morphological parameters and vision-related quality of life in keratoconus(KC) patients.METHODS: Totally 57 eyes of 30 KC patients who... AIM: To evaluate the effect of rigid gas permeable contact lens(RGP-CL) on corneal morphological parameters and vision-related quality of life in keratoconus(KC) patients.METHODS: Totally 57 eyes of 30 KC patients who were followed-up for more than two years, including 17 RGP wearers(32 eyes) and 13 non-wearers(25 eyes) were retrospectively analyzed. Initial medical history and corneal topography were collected at baseline. Corneal topography, corneal aberration, optical coherence tomography, and vision-related quality of life questionnaires were performed at the last follow-up.RESULTS: According to corneal topography, increase of the flattest keratometric values was higher in RGP wearers than in non-wearers(P=0.038). The morphological parameters, including symmetry index of front corneal curvature(P=0.004) and Baiocchi-Calossi-Versaci index front(P=0.047), were lower in RGP wearers than in nonwearers. Vertical coma was smaller in RGP wearers than non-wearers in 3.0, 5.0, 6.0, and 7.0 mm pupil diameters, respectively(P<0.05). The environmental triggering domain of ocular surface disease index was worse in RGP wearers as compared to non-wearers(P=0.003). At the last followup, there were no significant differences in constituent ratios of KC progression, corneal thickness topography, epithelial thickness topography, morphological parameters of corneal topography, and other questionnaire scores between the two groups(all P>0.05).CONCLUSION: Long-term use of RGP does not worsen KC but may cause corneal epithelial remodeling to increase symmetry of corneal anterior surface, reduce corneal vertical coma and improve visual quality. However, RGP wearing causes a slight decrease in vision-related quality of life. The occurrence of ocular surface symptoms is mainly associated with environmental triggering factors. 展开更多
关键词 KERATOCONUS rigid gas permeable contact lens morphological parameters corneal aberration visionrelated quality of life
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Intercropping Cocoa with Rice and Plantain Influencing Cocoa Morphological Parameters and Weed Biomass 被引量:1
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作者 A. O. Famaye G. O. Iremiren O. Olubamiwa A. E. Aigbekaen O. A. Fademi 《Journal of Agricultural Science and Technology(B)》 2011年第5期746-750,共5页
A field study was conducted at CRIN Uhonmora Substation, Edo State in Derived Guinea Savanna Zone of Nigeria between 2007 and 2008. The experiment determined influence of intercropping cocoa with rice and plantain at ... A field study was conducted at CRIN Uhonmora Substation, Edo State in Derived Guinea Savanna Zone of Nigeria between 2007 and 2008. The experiment determined influence of intercropping cocoa with rice and plantain at early stage of field establishment. Four treatments considered were cocoa (sole), cocoa/rice, cocoa/plantain and cocoa/rice/plantain. Spacing of 3.1 m apart was used for cocoa and plantain while rice was 30 cm. Plot laid out was randomized complete block design replicated three times. Data on cocoa morphological parameters comprising plant height, girth and leaf area as well as weed biomass were measured monthly. Cocoa survival count was also determined. Data collected were subjected to ANOVA, and LSD was used to separate the means. Survival count showed over 95% survival in all treatments without any significance differences. On plant height and leaf area vegetative growth were significantly higher (P 〈 0.05) in the intercrops than the sole cocoa but not significantly different in all the months. Plant vigour was significantly higher in cocoa/plantain intercrop. Cocoa/rice/plantain produced the least weed biomass while cocoa sole gave the highest. Therefore, cocoa/rice and cocoa/plantain intercrops could be recommended to cocoa farmers in Nigeria instead of sole planting at early age of field establishment. 展开更多
关键词 Cocoa INTERCROPPING morphological parameters WEED
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Influence of Active Charcoal and Plant Position on Some Morphological Parameters of a Local Variety of Okra (<i>Abelmoschus caillei</i>)
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作者 Kouame N’Guessan Koffi Ahébé Marie Hélène +2 位作者 Kouassi N’Dri Jacob N’Guessan N’Guessan Alain Yatty Kouadio Justin 《American Journal of Plant Sciences》 2017年第9期2021-2030,共10页
Okra is a plant rich in nutrients and is very well consumed in C&ocirc;te d’Ivoire. Despite its many benefits, the production of this vegetable is still weak in our country. The reasons for this include the inade... Okra is a plant rich in nutrients and is very well consumed in C&ocirc;te d’Ivoire. Despite its many benefits, the production of this vegetable is still weak in our country. The reasons for this include the inadequate selection of varieties, the high cost of inputs and the poverty of the soil for its cultivation. One of the alternatives for sustained production is to solve the problem of soil fertility. In the case of our work, the aim is to improve the yield of okra. To achieve this goal, experiments were undertaken to evaluate the impact of activated charcoal on morphological parameters of a local okra variety. For this purpose, the charcoal used was activated in three different times (activation time equal to 0 days, 15 days and 30 days). The experimental device used is a split-plot with three repetitions, each comprising 12 elementary plots. The various charcoals were buried the same day. Then, the seedling was done with two positions including outside position and inside position. Observations were made on 360 plants. An analysis of the variances was carried out on the morphological parameters. Fruit mass is the variable most influenced by activated charcoal. Thus, the greatest value of the mass was obtained with the charcoal CA0, with outside position. 展开更多
关键词 ACTIVATED Charcoal OKRA POSITION morphological parameters
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Study on Productivity Model of Herringbone-Like Laterals Wells and Optimization of Morphological Parameters Considering Threshold Pressure Gradient in Heavy Oil Reservoirs
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作者 Enhui Sun Jie Tan +2 位作者 Dong Zhang Wei Wang Songru Mu 《World Journal of Engineering and Technology》 2019年第2期302-313,共12页
Compared with conventional well, herringbone-like laterals wells can increase the area of oil release, and can reduce the number of wellhead slots of platforms,?and?also can greatly improve the development efficiency.... Compared with conventional well, herringbone-like laterals wells can increase the area of oil release, and can reduce the number of wellhead slots of platforms,?and?also can greatly improve the development efficiency. Based on threshold pressure gradient in heavy oil reservoir,?and?the applied principle of mirror reflection and superposition, the pressure distribution equation of herringbone-like laterals wells is obtained in heavy oil reservoir. Productivity model of herringbone-like laterals wells is proposed by reservoir-wellbore steady seepage. The example shows that the productivity model is great accuracy?to?predict the productivity of herringbone-like laterals wells. The model is used to analyze the branching length, branching angle, branching symmetry, branching position and spacing and their effects on productivity of herringbone-like laterals wells. The principle of optimizing the well shape of herringbone-like laterals wells is proposed. 展开更多
关键词 Threshold Pressure Gradient Herringbone-Like Laterals WELLS Heavy Oil RESERVOIRS PRODUCTIVITY Model Optimization of morphological parameters
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Inheritance of Main Morphological Traits and Chemical Parameters' Analysis of Oriental Tobacco
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作者 Vesselina Masheva Maria Kasheva 《Journal of Agricultural Science and Technology(A)》 2016年第6期417-422,共6页
This study was conducted to evaluate four different parental oriental varieties with their F1 crosses to estimate inheritance of some morphological traits, such as plant hight, number of leaves, total dry weigh and ch... This study was conducted to evaluate four different parental oriental varieties with their F1 crosses to estimate inheritance of some morphological traits, such as plant hight, number of leaves, total dry weigh and chemical compounds, especially nicotine and sugars during sun-curing period. The oriental varieties Kozarsko 541, Plovdiv 50 and Krumovgrad 17 from Bulgaria and Basma Xanthi 101 from Greece and their respective crosses with Basma Xanthi 101 were studied. The study was set up in 2014 and 2015 in experimental field of the Tobacco and Tobacco Products Institute, Plovdiv, using randomized block design with four replications. Common agricultural practices were applied during the growing season. The result indicated that in hybrid combination with parental varieties Kozarsko 541 and Plovdiv 50, except total dry weight, additive gene effects are important for traits height of plant and number of leaves. Height of plant and number of leaves are inherited partially dominant to parent with higher value and total dry weight inheritance was over dominant. In hybrid combination Krumovgrad 17 x Basma Xanthi 101, inheritance of the plant height and leaves number were over dominant type. Total dry weight is inherited partially dominant. In a word, prevailing mode for inheritance of plant hight and total dry weight was the over dominance and for number of leaves it was partial dominance. In sun-curing with yellowing stage, nicotine decreased and sugars increased in all tested varieties with a highest percentage in variety Kozarsko 541 (nicotine) and Krumovgrad 17 (sugars). 展开更多
关键词 Oriental tobacco inhedtanee character morphological traits chemical parameters.
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Three-dimensional histology:new visual approaches to morphological changes during neural regeneration
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作者 Hei Ming Lai Ho Man Ng Wutian Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第1期53-55,共3页
Three-dimensional(3D) histology utilizes tissue clearing techniques to turn intact tissues transparent,allowing rapid interrogation of tissue architecture in three dimensions.In this article,we summarized the availa... Three-dimensional(3D) histology utilizes tissue clearing techniques to turn intact tissues transparent,allowing rapid interrogation of tissue architecture in three dimensions.In this article,we summarized the available tissue clearing methods and classified them according to their physicochemical principles of operation,which provided a framework for one to choose the best techniques for various research settings.Recent attempts in addressing various questions regarding the degenerating and regenerating nervous system have been promising with the use of 3D histological techniques. 展开更多
关键词 three-dimensional histology tissue clearing neuronal morphology neuronal network
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Influence of forming process on three-dimensional morphology of TiB_2 particles in Al-Ti-B alloys 被引量:10
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作者 李鹏廷 李云国 +1 位作者 聂金凤 刘相法 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第3期564-570,共7页
A series of Al-Ti-B master alloys were prepared by different preparation routes,and the TiB2 particles in the master alloys were extracted and analyzed.It is found that the forming process has significant influence on... A series of Al-Ti-B master alloys were prepared by different preparation routes,and the TiB2 particles in the master alloys were extracted and analyzed.It is found that the forming process has significant influence on the three-dimensional morphology of TiB2 particles.Different preparation routes result in different reaction forms,which accounts for the morphology variation of TiB2 particles.When the Al-Ti-B master alloy is prepared using "halide salt" route,TiB2 particles exhibit hexagonal platelet morphology and are independent with each other.In addition,the reaction temperature almost does not have influence on the morphology of TiB2 particles.However,TiB2 particles exhibit different morphologies at different reaction temperatures when the master alloys are prepared with Al-3B and Ti sponge.When the master alloy is prepared at 850 ℃,a kind of TiB2 particle agglomeration forms with a size larger than 5 μm.The TiB2 particles change to layered stacking morphology even dendritic morphology with the reaction temperature reaching up to 1200 ℃. 展开更多
关键词 Al-Ti-B alloy TIB2 forming process three-dimensional morphology
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Shear behavior of intact granite under thermo-mechanical coupling and three-dimensional morphology of shear-formed fractures 被引量:1
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作者 Bing Chen Baotang Shen Haiyang Jiang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第3期523-537,共15页
The shear failure of intact rock under thermo-mechanical(TM)coupling conditions is common,such as in enhanced geothermal mining and deep mine construction.Under the effect of a continuous engineering disturbance,shear... The shear failure of intact rock under thermo-mechanical(TM)coupling conditions is common,such as in enhanced geothermal mining and deep mine construction.Under the effect of a continuous engineering disturbance,shear-formed fractures are prone to secondary instability,posing a severe threat to deep engineering.Although numerous studies regarding three-dimensional(3D)morphologies of fracture surfaces have been conducted,the understanding of shear-formed fractures under TM coupling conditions is limited.In this study,direct shear tests of intact granite under various TM coupling conditions were conducted,followed by 3D laser scanning tests of shear-formed fractures.Test results demonstrated that the peak shear strength of intact granite is positively correlated with the normal stress,whereas it is negatively correlated with the temperature.The internal friction angle and cohesion of intact granite significantly decrease with an increase in the temperature.The anisotropy,roughness value,and height of the asperities on the fracture surfaces are reduced as the normal stress increases,whereas their variation trends are the opposite as the temperature increases.The macroscopic failure mode of intact granite under TM coupling conditions is dominated by mixed tensileeshear and shear failures.As the normal stress increases,intragranular fractures are developed ranging from a local to a global distribution,and the macroscopic failure mode of intact granite changes from mixed tensileeshear to shear failure.Finally,3D morphological characteristics of the asperities on the shear-formed fracture surfaces were analyzed,and a quadrangular pyramid conceptual model representing these asperities was proposed and sufficiently verified. 展开更多
关键词 Thermo-mechanical(TM)coupling Peak shear strength three-dimensional(3D)morphological characterization Failure mode Quadrangular pyramid model
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Nucleation and three-dimensional morphology of intragranular ferrite in a vanadium microalloyed steel
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作者 Kaiming Wu Xinlai He 《Journal of University of Science and Technology Beijing》 CSCD 2005年第4期326-328,共3页
The formation of intragranular ferrite at inclusions was analyzed by SEM-EDX in a vanadium microalloyed steel with an excess amount of sulfur. The precipitation of MnS at aluminum oxides may result in Mn depletion, wh... The formation of intragranular ferrite at inclusions was analyzed by SEM-EDX in a vanadium microalloyed steel with an excess amount of sulfur. The precipitation of MnS at aluminum oxides may result in Mn depletion, which, in turn, promotes the formation of intragranular ferrite. The morphology of intragranular ferrite changed with undercooling. At higher temperatures intragranular ferrite is nearly equiaxed whereas it is plate-like at lower temperatures. 展开更多
关键词 microalloyed steels intragranular ferfite NUCLEATION three-dimensional morphology
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Integration system research and development for three-dimensional laser scanning information visualization in goaf 被引量:1
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作者 罗周全 黄俊杰 +2 位作者 罗贞焱 汪伟 秦亚光 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第7期1985-1994,共10页
An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, clo... An integration processing system of three-dimensional laser scanning information visualization in goaf was developed. It is provided with multiple functions, such as laser scanning information management for goaf, cloud data de-noising optimization, construction, display and operation of three-dimensional model, model editing, profile generation, calculation of goaf volume and roof area, Boolean calculation among models and interaction with the third party soft ware. Concerning this system with a concise interface, plentiful data input/output interfaces, it is featured with high integration, simple and convenient operations of applications. According to practice, in addition to being well-adapted, this system is favorably reliable and stable. 展开更多
关键词 GOAF laser scanning visualization integration system 1 Introduction The goaf formed through underground mining of mineral resources is one of the main disaster sources threatening mine safety production [1 2]. Effective implementation of goaf detection and accurate acquisition of its spatial characteristics including the three-dimensional morphology the spatial position as well as the actual boundary and volume are important basis to analyze predict and control disasters caused by goaf. In recent years three-dimensional laser scanning technology has been effectively applied in goaf detection [3 4]. Large quantities of point cloud data that are acquired for goaf by means of the three-dimensional laser scanning system are processed relying on relevant engineering software to generate a three-dimensional model for goaf. Then a general modeling analysis and processing instrument are introduced to perform subsequent three-dimensional analysis and calculation [5 6]. Moreover related development is also carried out in fields such as three-dimensional detection and visualization of hazardous goaf detection and analysis of unstable failures in goaf extraction boundary acquisition in stope visualized computation of damage index aided design for pillar recovery and three-dimensional detection
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Antidiastole Value of Three-dimensional Ultrasonography and Power Doppler between Uterine Parenchyma Lumps and Endometrial Cancer:A Retrospective Study 被引量:12
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作者 Yan ZHANG Jing CHEN +1 位作者 Zeng ZHEN Xiao-yan XU 《Current Medical Science》 SCIE CAS 2019年第5期816-819,共4页
Sometimes endometrial polyps,submucosal myomas,and endometrial cancer show similar findings under ultrasonography.The aim of this study was to assess the antidiastole value of blood flow parameters using three-dimensi... Sometimes endometrial polyps,submucosal myomas,and endometrial cancer show similar findings under ultrasonography.The aim of this study was to assess the antidiastole value of blood flow parameters using three-dimensional(3D)power Doppler ultrasonography angiography(PDA)between endometrial cancer and uterine parenchyma lumps.The data of the blood flow indices in 3D-PDA including the vascularization index(VI),flow index(FI),and vascularization flow index(VFI)in 40 patients with endometrial cancer and 41 patients with uterine parenchyma lumps(endometrial polyps and submucosal myomas)were retrospectively analysed and compared utilizing Virtual Organ Computer-aided AnaLysis(VOCAL)software.The results showed that all the blood flow parameters(VI,FI,VFI)were significantly higher in women with endometrial cancer than in those with uterine parenchyma lumps(P<0.001).The area under the curve of ROC of VI,FI,and VFI was 0.98,0.84,and 0.97,respectively.Thus,the best predictor of endometrial carcinoma was VI with a sensitivity of 97.0% and a specificity of 91.0%.The optimal cutoff value of VI was 4.06%.Our data demonstrated that all of the blood flow signal parameters(including VI,FI,and VFI)in 3D power Doppler ultrasonography had significant antidiastole values between endometrial cancer and uterine parenchyma lumps to assist clinicians in properly diagnosing patients. 展开更多
关键词 power DOPPLER three-dimensional ultrasound UTERINE PARENCHYMA lump ENDOMETRIAL CARCINOMA BLOOD flow signal parameter
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Evaluation of Three-dimensional Urban Expansion: A Case Study of Yangzhou City, Jiangsu Province, China 被引量:11
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作者 QIN Jing FANG Chuanglin +2 位作者 WANG Yang LI Guangdong WANG Shaojian 《Chinese Geographical Science》 SCIE CSCD 2015年第2期224-236,共13页
With rapid urban development in China in the last two decades, the three-dimensional(3D) characteristic has been the main feature of urban morphology. However, the vast majority of researches of urban growth have focu... With rapid urban development in China in the last two decades, the three-dimensional(3D) characteristic has been the main feature of urban morphology. However, the vast majority of researches of urban growth have focused on the planar area(two-dimensional(2D)) expansion. Few studies have been conducted from a 3D perspective. In this paper, the 3D urban expansion of the Yangzhou City, Jiangsu Province, China from 2003 to 2012 was evaluated based on Geographical Information System(GIS) tools and high-resolution remote sensing images. Four indices, namely weighted average height of buildings, volume of buildings, 3D expansion intensity and 3D fractal dimension are used to quantify the 3D urban expansion. The weighted average height of buildings and the volume of buildings are used to illustrate the temporal change of the 3D urban morphology, while the other two indices are used to calculate the expansion intensity and the fractal dimension of the 3D urban morphology. The results show that the spatial distribution of the high-rise buildings in Yangzhou has significantly spread and the utilization of the 3D space of Yangzhou has become more efficient and intensive. The methods proposed in this paper laid a foundation for a wide range of study of 3D urban morphology changes. 展开更多
关键词 three-dimensional urban morphology high-resolution remote sensing image three-dimensional expansion three-dimen-sional fractal Yangzhou City China
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Quantitative determination of PFC3D microscopic parameters 被引量:5
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作者 LI Zhuo RAO Qiu-hua 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第3期911-925,共15页
It is important to calibrate micro-parameters for applying partied flow code(PFC)to study mechanical characteristics and failure mechanism of rock materials.Uniform design method is firstly adopted to determine the mi... It is important to calibrate micro-parameters for applying partied flow code(PFC)to study mechanical characteristics and failure mechanism of rock materials.Uniform design method is firstly adopted to determine the microscopic parameters of parallel-bonded particle model for three-dimensional discrete element particle flow code(PFC3D).Variation ranges of microscopic of the microscopic parameters are created by analyzing the effects of microscopic parameters on macroscopic parameters(elastic modulus E,Poisson ratio v,uniaxial compressive strengthσc,and ratio of crack initial stress to uniaxial compressive strengthσci/σc)in order to obtain the actual uniform design talbe.The calculation equations of the microscopic and macroscopic parameters of rock materials can be established by the actual uniform design table and the regression analysis and thus the PFC3D microscopic parameters can be quantitatively determined.The PFC3D simulated results of the intact and pre-cracked rock specimens under uniaxial and triaxial compressions(including the macroscopic mechanical parameters,stress−strain curves and failure process)are in good agreement with experimental results,which can prove the validity of the calculation equations of microscopic and macroscopic parameters. 展开更多
关键词 quantitative relationship of microscopic and macroscopic parameters uniform design method three-dimensional particle flow code(PFC3D) ROCK
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