Three-Dimensional CA-LBM Numerical Model and Experimental Verification of Cs2AgBiBr6 Perovskite Single Crystals Grown by Solution Method

A three-dimensional cellular automata-lattice Boltzmann (CA-LBM) coupling model is established to simulate the facet growth process and the controlled cooling growth process of Cs2AgBiBr6 perovskite single crystals. In this model, the LBM method is used to calculate the real-time solute field, the CA method is used to simulate the crystal growth process driven by supersaturation of solute, and the geometric parameter g related to the adjacent grid is introduced to reduce the influence of grid anisotropy. The verification of the model is achieved by comparing the simulation results with the experimental results. The comparison results show that a smaller cooling rate is helpful for the growth of large-size single crystals, which verifies the rationality and correctness of the model.

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Three-Dimensional CA-LBM Model of Silicon Facet Formation during Directional Solidification

Crystals ◽

10.3390/cryst10080669 ◽

2020 ◽

Vol 10 (8) ◽

pp. 669

Author(s):

Wang Ma ◽

Ri Li ◽

Hongjian Chen

Keyword(s):

Directional Solidification ◽

Lattice Boltzmann ◽

Growth Process ◽

Three Dimensional ◽

Coupling Model ◽

Interface Energy ◽

Calculation Model ◽

Crystal Growth Process ◽

Anisotropic Function ◽

Boltzmann Method

A new 3D cellular automata-lattice Boltzmann method (CA-LBM) coupling model is proposed to simulate the formation of facet and facet dendrites in directional solidification. In this model, the CA method is used to simulate the crystal growth process and the LBM method is used to simulate the physical field in the calculation area. A new three-dimensional anisotropic function is introduced, and the model is modified by interpolation and neighborhood restriction. We add the remelting calculation model. The interaction between interface energy anisotropy and dynamic anisotropy is solved reasonably. The growth process and morphology of small plane and small plane dendrites were simulated.

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Central ossifying fibroma of mandible

BMJ Case Reports ◽

10.1136/bcr-2020-239286 ◽

2020 ◽

Vol 13 (12) ◽

pp. e239286

Author(s):

Kumar Nilesh ◽

Prashant Punde ◽

Nitin Shivajirao Patil ◽

Amol Gautam

Keyword(s):

Fibrous Tissue ◽

Three Dimensional ◽

Facial Asymmetry ◽

Ossifying Fibroma ◽

Mandible Reconstruction ◽

Three Dimensional Printing ◽

Osseous Lesion ◽

Large Size ◽

Dimensional Printing

Ossifying fibroma (OF) is a rare, benign, fibro-osseous lesion of the jawbone characterised by replacement of the normal bone with fibrous tissue. The fibrous tissue shows varying amount of calcified structures resembling bone and/or cementum. The central variant of OF is rare, and shows predilection for mandible among the jawbone. Although it is classified as fibro-osseous lesion, it clinically behaves as a benign tumour and can grow to large size, causing bony swelling and facial asymmetry. This paper reports a case of large central OF of mandible in a 40-year-old male patient. The lesion was treated by segmental resection of mandible. Reconstruction of the surgical defect was done using avascular fibula bone graft. Role of three-dimensional printing of jaw and its benefits in surgical planning and reconstruction are also highlighted.

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Flux Method Growth of Large Size Group IV–V 2D GeP Single Crystals and Photoresponse Application

Crystals ◽

10.3390/cryst11030235 ◽

2021 ◽

Vol 11 (3) ◽

pp. 235

Author(s):

Shuqi Zhao ◽

Tongtong Yu ◽

Ziming Wang ◽

Shilei Wang ◽

Limei Wei ◽

...

Keyword(s):

Raman Spectroscopy ◽

Single Crystals ◽

High Performance ◽

Group Iv ◽

X Ray Diffraction ◽

High Quality ◽

Practical Applications ◽

Large Size ◽

Growth Method ◽

Polarized Raman

Two-dimensional (2D) materials driven by their unique electronic and optoelectronic properties have opened up possibilities for their various applications. The large and high-quality single crystals are essential to fabricate high-performance 2D devices for practical applications. Herein, IV-V 2D GeP single crystals with high-quality and large size of 20 × 15 × 5 mm3 were successfully grown by the Bi flux growth method. The crystalline quality of GeP was confirmed by high-resolution X-ray diffraction (HRXRD), Laue diffraction, electron probe microanalysis (EPMA) and Raman spectroscopy. Additionally, intrinsic anisotropic optical properties were investigated by angle-resolved polarized Raman spectroscopy (ARPRS) and transmission spectra in detail. Furthermore, we fabricated high-performance photodetectors based on GeP, presenting a relatively large photocurrent over 3 mA. More generally, our results will significantly contribute the GeP crystal to the wide optoelectronic applications.

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Optical Encryption Based on Computer Generated Holograms in Photopolymer

Polymers ◽

10.3390/polym13091358 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1358

Author(s):

Taihui Wu ◽

Jianshe Ma ◽

Chengchen Wang ◽

Haibei Wang ◽

Liangcai Cao ◽

...

Keyword(s):

High Speed ◽

Three Dimensional ◽

Angular Spectrum ◽

Quick Response ◽

Response Code ◽

Optical Encryption ◽

Large Size ◽

Quick Response Code ◽

Computer Generated Holograms ◽

Encryption Method

An optical encryption method based on computer generated holograms printing of photopolymer is presented. Fraunhofer diffraction is performed based on the Gerchberg-Saxton algorithm, and a hologram of the Advanced Encryption Standard encrypted Quick Response code is generated to record the ciphertext. The holograms of the key and the three-dimensional image are generated by the angular spectrum diffraction algorithm. The experimental results show that large-size encrypted Quick Response (QR) code and miniature keys can be printed in photopolymers, which has good application prospects in optical encryption. This method has the advantages of high-density storage, high speed, large fault tolerance, and anti-peeping.

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Numerical Analysis of Difficulties of Growing Large-Size Bulk β-Ga2O3 Single Crystals with the Czochralski Method

Crystals ◽

10.3390/cryst11010025 ◽

2020 ◽

Vol 11 (1) ◽

pp. 25

Author(s):

Xia Tang ◽

Botao Liu ◽

Yue Yu ◽

Sheng Liu ◽

Bing Gao

Keyword(s):

Crystal Growth ◽

Single Crystals ◽

Czochralski Method ◽

Liquid Interface ◽

Spiral Growth ◽

Growth Time ◽

Large Size ◽

Crystal Diameter ◽

Solid Liquid Interface ◽

Solid Liquid

The difficulties in growing large-size bulk β-Ga2O3 single crystals with the Czochralski method were numerically analyzed. The flow and temperature fields for crystals that were four and six inches in diameter were studied. When the crystal diameter is large and the crucible space becomes small, the flow field near the crystal edge becomes poorly controlled, which results in an unreasonable temperature field, which makes the interface velocity very sensitive to the phase boundary shape. The effect of seed rotation with increasing crystal diameter was also studied. With the increase in crystal diameter, the effect of seed rotation causes more uneven temperature distribution. The difficulty of growing large-size bulk β-Ga2O3 single crystals with the Czochralski method is caused by spiral growth. By using dynamic mesh technology to update the crystal growth interface, the calculation results show that the solid–liquid interface of the four-inch crystal is slightly convex and the center is slightly concave. With the increase of crystal growth time, the symmetry of cylindrical crystal will be broken, which will lead to spiral growth. The numerical results of the six-inch crystal show that the whole solid–liquid interface is concave and unstable, which is not conducive to crystal growth.

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The master bay plan problem: a solution method based on its connection to the three-dimensional bin packing problem

IMA Journal of Management Mathematics ◽

10.1093/imaman/14.3.251 ◽

2003 ◽

Vol 14 (3) ◽

pp. 251-269 ◽

Cited By ~ 26

Author(s):

A. Sciomachen

Keyword(s):

Bin Packing ◽

Solution Method ◽

Three Dimensional ◽

Packing Problem ◽

Bin Packing Problem

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Three-dimensional visualization of the inner structure of single crystals by step-scanning white X-ray section topography

Journal of Synchrotron Radiation ◽

10.1107/s090904950603384x ◽

2006 ◽

Vol 13 (6) ◽

pp. 484-488 ◽

Cited By ~ 8

Author(s):

Taihei Mukaide ◽

Kentaro Kajiwara ◽

Takashi Noma ◽

Kazuhiro Takada

Keyword(s):

Single Crystals ◽

Three Dimensional ◽

X Ray ◽

Section Topography

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Analysis of SiC CVD Growth in a Horizontal Hot-Wall Reactor by Experiment and 3D Modelling

Materials Science Forum ◽

10.4028/www.scientific.net/msf.556-557.61 ◽

2007 ◽

Vol 556-557 ◽

pp. 61-64

Author(s):

Y. Shishkin ◽

Rachael L. Myers-Ward ◽

Stephen E. Saddow ◽

Alexander Galyukov ◽

A.N. Vorob'ev ◽

...

Keyword(s):

Growth Rate ◽

Growth Process ◽

Three Dimensional ◽

Chemical Species ◽

3D Modelling ◽

Complete Model ◽

Cvd Growth ◽

Dimensional Simulation ◽

Insight Into ◽

Hot Zone

A fully-comprehensive three-dimensional simulation of a CVD epitaxial growth process has been undertaken and is reported here. Based on a previously developed simulation platform, which connects fluid dynamics and thermal temperature profiling with chemical species kinetics, a complete model of the reaction process in a low pressure hot-wall CVD reactor has been developed. Close agreement between the growth rate observed experimentally and simulated theoretically has been achieved. Such an approach should provide the researcher with sufficient insight into the expected growth rate in the reactor as well as any variations in growth across the hot zone.

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