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The 3-dimensional morphology of dendrite during equiaxed solidification of an Al-5 wt.% Cu alloy

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Journal of Materials Science & Technology 2019年第3期35卷 239-247页

作者： Xiaoping Ma Dianzhong Li Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences

In a sample quenched during equiaxed solidification of an Al-5 wt.% Cu alloy, the multi-scales 3-dimensional morphology of equiaxed dendrite was observed. The slim primary stem and secondary branches constitute the frame of dendrite, and rows of dense tertiary branches further divide the 3-dimensional space. In the divided space, the quartic branches grow further. The dendritic branches,which are perpendicular to each other, can change their growth directions and coalesce into a whole. In the tertiary branches and quartic branches, the formation of double branch structures is induced by competitive growth. The branch that wins in the competitive growth will produce a cabbage-like structure by wrapping the failed branches. In addition, the side branch can also wrap the original parent branch to produce cabbage-like structures. Depending on the historical growth direction, the dendritic arms can form vein-like and spicate structures, and the shapes of single dendritic arm may be the cylinder, plate and trapezoid platform. According to the compositions and etching morphology, the single dendritic arm in the final solidification structures should coalesce from a fine porous structure. The porous structures at different length-scales are principally induced by the preferential growth. Based on 3-dimensional morphology of equiaxed dendrite, a new research object for the investigation of microsegregation was suggested.

关键词： Equiaxed dendrite 3-dimensional morphology Competitive growth Coalescence Segregation

The Fourth Power Mean of the General 3-dimensional Kloostermann Sums mod p

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Acta Mathematica Sinica,English Series 2019年第3期35卷 369-377页

作者： Wen Peng ZHANG Xing Xing LV School of Mathematics Northwest University

The main purpose of this paper is using the analytic methods, the solutions of the congruence equation mod p and the properties of Gauss sums to study the computational problem of one kind fourth power mean of the gen... 详细信息

关键词： The general 3-dimensional Kloostermann sums the fourth power mean dirichlet character asymptotic formula

Study on the stability and 3-dimensional character for natural convection in a rectangular cavity heated from below

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Science China(Technological Sciences) 2010年第6期53卷 1647-1654页

作者： ZHAN NaiYan1,2,XU PeiWei1,SUN ShiMei,YANG Mo2 & LIU Jun3 1 Scool of Municipal and Environmental Engineering,Jilin Institute of Architectural and Civil Engineering,Changchun 130021,China 2 College of Power Engineering,University of Shanghai for Science and Technology,Shanghiai 200093,China 3 College of Power Engineering,Jilin University,Changchun 130000,China Scool of Municipal and Environmental Engineering Jilin Institute of Architectural and Civil Engineering Changchun China College of Power Engineering University of Shanghai for Science and Technology Shanghiai China College of Power Engineering Jilin University Changchun China

Natural convection of air is numerically simulated in a 3-dimensional rectangular cavity heated from below using SIMPLE algorithm with a QUICK scheme.The results suggest that when all lateral walls are adiabatic,the fluid rolls occur along the long axis.When the Rayleigh number is smaller,the flow is of 2-dimensional character,and the rolls shapes are similar.The average Nusselt numbers in the central part of the cavity are similar.The average Nusselt numbers in the part near by the cavity are different.According to the comparison of 3-dimensional results with 2-dimensional results,the flow patterns and heat transfer in the central part of the cavity can be assumed as a 2-dimensional flow,While those in the part near by the cavity can not.With increasing Rayleigh number,the flow is 3-dimensional characteristic.The 3-dimensional result accords with the experimental result.When all lateral walls are adiabatic,the ten rolls occur along the long axis.But when lateral walls are heated or cooled,the rolls disappear along the long axis and two rolls occur along the short axis.The rotation direction of the rolls is reversed.When Rayleigh number is over some critical value,flow and heat transfer will be asymmetry,indicating unsteady oscillation occurs.By nonlinear analyses,it is shown that with increasing Rayleigh number,flow and heat transfer will change from steady state to unsteady state through HOPF bifurcation,and transition to chaos will occur through multi-periodical oscillation.

关键词： Critical Raleigh number 3-dimensional character lateral boundaries nonlinear characteristic bifurcation

Primary 3-dimensional culture of mouse hepatocytes

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Chinese Science Bulletin 2000年第20期45卷 1878-1883页

作者： Jiman He Meifu Feng Chinese Acad Sci Inst Zool State Key Lab Biomembrane & Membrane Biotechnol Beijing 100080 Peoples R China

Complex 3-dimensional structures with good functions have been obtained under the primary mixcoculture of mouse hepatocytes with mouse liver fibroblasts without serum. Albumin secretion is kept above 10 μg/106 cells and urea synthesis reaches 25 μg/106 on the 7th day of culture. Avoiding serum affection, liver fibroblasts’ effects on hepatocytes’ viability, functions and 3-dimensional structure forming in primary serum-free culture have been studied. Important effects of the mesenchyma, especially the direct adherence of fibroblasts to hepatocytes, are shown.

关键词： hepatocyte primary culture 3-dimensional structure.

A 3-dimensional DATA MODEL FOR VISUALIZING CLOVERLEAF JUNCTION IN A CITY MODEL

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Geo-Spatial Information Science 1999年第1期2卷 9-15页

作者： Chen Jun Sun Min Zhou Qiming National Laboratory for Information Engineering in Surveying Mapping and Remote Sensing WTUSM Wuhan China

The research work has been seldom done about cloverleaf junction expression in a 3-dimensional city model (3DCM). The main reason is that the cloverleaf junction is often in a complex and enormous construction. Its main body is bestraddle in air,and has aerial intersections between its parts. This complex feature made cloverleaf junction quite different from buildings and terrain, therefore, it is difficult to express this kind of spatial objects in the same way as for buildings and terrain. In this paper,authors analyze spatial characteristics of cloverleaf junction, propose an all-constraint points TIN algorithm to partition cloverleaf junction road surface, and develop a method to visualize cloverleaf junction road surface using TIN. In order to manage cloverleaf junction data efficiently, the authors also analyzed the mechanism of 3DCM data management, extended BLOB type in relational database, and combined R-tree index to manage 3D spatial data. Based on this extension, an appropriate data

关键词： 3-dimensional city model (3DCM) GIS cloverleaf junction data structure database

Rota-Baxter Operators on 3-dimensional Lie Algebras and Solutions of the Classical Yang-Baxter Equation

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Communications in Mathematical Research 2019年第1期35卷 81-96页

作者： Cheng Yong-sheng Wu Lin-li Wang Pan-yin Du Xian-kun School of Mathematics and Statistics Henan UniversityKaifengHenan475004 不详

In this paper,we compute Rota-Baxter operators on the 3-dimensional Lie algebra g whose derived algebra’s dimension is 2.Furthermore,we give the corresponding solutions of the classical Yang-Baxter equation in the 6-dimensional Lie algebras g ■ _(ad~*) g~* and some new structures of left-symmetric algebra induced from g and its Rota-Baxter operators.

关键词： Rota-Baxter operators 3-dimensional Lie algebra classical Yang-Baxter equation left-symmetric algebra

3-dimensional Skew-symmetric Algebras and the Variety of Horn-Lie Algebras

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Algebra Colloquium 2018年第4期25卷 547-566页

作者： Elisabeth Remm LMIA Universite de Hante-A1sace (LMIAEA 3993)F-68100 MulhouseFrance

An algebra is called skew-symmetric if its multiplication operation is a skew-symmetric bilinear application.We determine all these algebras in dimension 3 over a field of characteristic different from 2.As an application,we determine the subvariety of 3-dimensional Horn-Lie algebras.For this type of algebra,we study also the case of dimension 4.

关键词： 3-dimensional skew-symmetric algebras variety of Hom-Lie algebras

The role of 3-dimensional ultrasound for the diagnosis of congenital uterine anomalies

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Open Journal of Obstetrics and Gynecology 2011年第4期1卷 239-242页

作者： Efraim Zohav Yaakov Melcer Ilan Tur-Kaspa Jacob Rabinson Eyal Y. Anteby Raoul Orvieto 不详

Objectives: To demonstrate the value of 3-dimensional (3-D) ultrasound (US) in the diagnosis of congenital uterine anomalies. Methods: Fifty one infertile patients referred to our US unit during 12 years period, with suspected diagnosis of congenital uterine anomalies by previous HSG or 2D US examinations, were evaluated by transvaginal 3-D US. The 3-D US diagnoses were compared to the initial HSG diagnosis, and to hysteroscopic evaluation when performed. Results: 3-D scan confirmed the initial HSG diagnosis in 27 out of 51 (52.9%) women. The concordancy rates between the initial diagnosis by HSG and 3-D US results were 30.4% for bicornuate uterus;75% for arcuate uterus;83% for septate uterus;and 80% for unicornuate uterus. Of the 13 cases with normal HSG and suspicious 2-D US, 30.8% were found to be normal by 3D sonography. In cases where hysteroscopy was done, the results were 100% in concordance with the 3-D US evaluations. Conclusions: 3-D US is an accurate test for the assessment of uterine congenital anomalies. Its ability to concomitantly visualized, the external uterine contour with the uterine cavity on the same coronal plan, makes this noninvasive, easy to perform test the procedure of choice for the diagnosis of uterine anomalies.

关键词： Mullerian Anomalies 3-dimensional (3-D) Ultrasonography Hysterosalpingography Hysteroscopy

APPLICATION OF 3-dimensional PHOTO-ELASTIC MODEL WITH VARIANT MODULUS TO GEOLOGY OF NANTONG MINE AREA IN SICHUAN PROVINCE

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Chinese Science Bulletin 1988年第14期33卷 1188-1191页

作者：黄庆华王公炳 Institute of Geomechanics CAGS Beijing Chongqing University

The area we modelled is at 28°52′—29°2′N and 106°50′—106°58′E, 17.5 km long and 13 km wide and containing the NS-trending structure, Xianjiaping anticline, Bamianshan syncline and Wuguishan anticline in the ... 详细信息

关键词： tectonic stressfield coal-gas burst 3-dimensional simulation Sichuan Province