Aqueous oxidation reaction enabled layer-by-layer corrosion of semiconductor nanoplates into single-crystalline 2D nanocrystals with single layer accuracy and ionic surface capping

A controllable aqueous oxidation reaction enabled layer-by-layer corrosion has been proposed to prepare high-quality two-dimensional (2D) semiconductor nanocrystals with single layer accuracy and well-retained hexagonal shapes.

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Superconductivity and magnetotransport of single-crystalline NbSe2nanoplates grown by chemical vapour deposition

Nanoscale ◽

10.1039/c7nr06617a ◽

2017 ◽

Vol 9 (43) ◽

pp. 16591-16595 ◽

Cited By ~ 9

Author(s):

Yi-Chao Zou ◽

Zhi-Gang Chen ◽

Enze Zhang ◽

Faxian Xiu ◽

Syo Matsumura ◽

...

Keyword(s):

Chemical Vapour Deposition ◽

Vapour Deposition ◽

Chemical Vapour ◽

Two Dimensional ◽

Deposition Method ◽

High Quality ◽

Single Crystalline ◽

Dimensional Characteristic ◽

Chemical Vapour Deposition Method

High-quality NbSe2nanoplates can be grown by a facile chemical vapour deposition method, exhibiting a two-dimensional characteristic in their superconductivities.

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Epitaxial growth manner and structure of superconducting oxide films

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173145 ◽

1990 ◽

Vol 48 (4) ◽

pp. 2-3

Author(s):

Yoshichika Bando ◽

Takahito Terashima ◽

Kenji Iijima ◽

Kazunuki Yamamoto ◽

Kazuto Hirata ◽

...

Keyword(s):

Ultrathin Films ◽

Film Surface ◽

High Energy ◽

Epitaxial Films ◽

Layer By Layer ◽

Initial Growth ◽

In Situ Growth ◽

High Quality ◽

Activated Reactive Evaporation

The high quality thin films of high-Tc superconducting oxide are necessary for elucidating the superconducting mechanism and for device application. The recent trend in the preparation of high-Tc films has been toward “in-situ” growth of the superconducting phase at relatively low temperatures. The purpose of “in-situ” growth is to attain surface smoothness suitable for fabricating film devices but also to obtain high quality film. We present the investigation on the initial growth manner of YBCO by in-situ reflective high energy electron diffraction (RHEED) technique and on the structural and superconducting properties of the resulting ultrathin films below 100Å. The epitaxial films have been grown on (100) plane of MgO and SrTiO, heated below 650°C by activated reactive evaporation. The in-situ RHEED observation and the intensity measurement was carried out during deposition of YBCO on the substrate at 650°C. The deposition rate was 0.8Å/s. Fig. 1 shows the RHEED patterns at every stage of deposition of YBCO on MgO(100). All the patterns exhibit the sharp streaks, indicating that the film surface is atomically smooth and the growth manner is layer-by-layer.

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Homogeneous 2D and 3D alignment of cardiomyocyte in dilated cardiomyopathy revealed by intravital heart imaging

Scientific Reports ◽

10.1038/s41598-021-94100-z ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Kiyoshi Masuyama ◽

Tomoaki Higo ◽

Jong-Kook Lee ◽

Ryohei Matsuura ◽

Ian Jones ◽

...

Keyword(s):

Heart Failure ◽

Dilated Cardiomyopathy ◽

Cardiac Dysfunction ◽

Three Dimensional ◽

Single Layer ◽

Specific Pattern ◽

Two Dimensional ◽

Heart Imaging ◽

Novel Method ◽

2D And 3D

AbstractIn contrast to hypertrophic cardiomyopathy, there has been reported no specific pattern of cardiomyocyte array in dilated cardiomyopathy (DCM), partially because lack of alignment assessment in a three-dimensional (3D) manner. Here we have established a novel method to evaluate cardiomyocyte alignment in 3D using intravital heart imaging and demonstrated homogeneous alignment in DCM mice. Whilst cardiomyocytes of control mice changed their alignment by every layer in 3D and position twistedly even in a single layer, termed myocyte twist, cardiomyocytes of DCM mice aligned homogeneously both in two-dimensional (2D) and in 3D and lost myocyte twist. Manipulation of cultured cardiomyocyte toward homogeneously aligned increased their contractility, suggesting that homogeneous alignment in DCM mice is due to a sort of alignment remodelling as a way to compensate cardiac dysfunction. Our findings provide the first intravital evidence of cardiomyocyte alignment and will bring new insights into understanding the mechanism of heart failure.

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High performance self-powered photodetector based on 1D Te-2D WS2 mixed-dimensional heterostructure

Nanoscale Advances ◽

10.1039/d1na00073j ◽

2021 ◽

Author(s):

Lixiang Han ◽

Mengmeng Yang ◽

Peiting Wen ◽

Wei Gao ◽

nengjie huo ◽

...

Keyword(s):

High Performance ◽

Van Der Waals ◽

Sharp Interface ◽

Two Dimensional ◽

High Quality ◽

One Dimensional ◽

Self Powered

One dimensional (1D)-two dimensional (2D) van der Waals (vdWs) mixed-dimensional heterostructures with advantages of atomically sharp interface, high quality and good compatibility have attracted tremendous attention in recent years. The...

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RLC-GNN: An Improved Deep Architecture for Spatial-Based Graph Neural Network with Application to Fraud Detection

Applied Sciences ◽

10.3390/app11125656 ◽

2021 ◽

Vol 11 (12) ◽

pp. 5656

Author(s):

Yufan Zeng ◽

Jiashan Tang

Keyword(s):

Numerical Experiments ◽

State Of The Art ◽

Single Layer ◽

Fraud Detection ◽

Layer By Layer ◽

Residual Structure ◽

Detection Algorithms ◽

Deep Architecture ◽

Graph Neural Networks ◽

Node Embeddings

Graph neural networks (GNNs) have been very successful at solving fraud detection tasks. The GNN-based detection algorithms learn node embeddings by aggregating neighboring information. Recently, CAmouflage-REsistant GNN (CARE-GNN) is proposed, and this algorithm achieves state-of-the-art results on fraud detection tasks by dealing with relation camouflages and feature camouflages. However, stacking multiple layers in a traditional way defined by hop leads to a rapid performance drop. As the single-layer CARE-GNN cannot extract more information to fix the potential mistakes, the performance heavily relies on the only one layer. In order to avoid the case of single-layer learning, in this paper, we consider a multi-layer architecture which can form a complementary relationship with residual structure. We propose an improved algorithm named Residual Layered CARE-GNN (RLC-GNN). The new algorithm learns layer by layer progressively and corrects mistakes continuously. We choose three metrics—recall, AUC, and F1-score—to evaluate proposed algorithm. Numerical experiments are conducted. We obtain up to 5.66%, 7.72%, and 9.09% improvements in recall, AUC, and F1-score, respectively, on Yelp dataset. Moreover, we also obtain up to 3.66%, 4.27%, and 3.25% improvements in the same three metrics on the Amazon dataset.

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Investigation of the Heteroepitaxial Process Optimization of Ge Layers on Si (001) by RPCVD

Nanomaterials ◽

10.3390/nano11040928 ◽

2021 ◽

Vol 11 (4) ◽

pp. 928

Author(s):

Yong Du ◽

Zhenzhen Kong ◽

Muhammet Toprak ◽

Guilei Wang ◽

Yuanhao Miao ◽

...

Keyword(s):

High Temperature ◽

Buffer Layer ◽

Layer Thickness ◽

Growth Temperature ◽

Crystalline Quality ◽

Initial Growth ◽

Two Dimensional ◽

High Quality ◽

Reduced Pressure

This work presents the growth of high-quality Ge epilayers on Si (001) substrates using a reduced pressure chemical vapor deposition (RPCVD) chamber. Based on the initial nucleation, a low temperature high temperature (LT-HT) two-step approach, we systematically investigate the nucleation time and surface topography, influence of a LT-Ge buffer layer thickness, a HT-Ge growth temperature, layer thickness, and high temperature thermal treatment on the morphological and crystalline quality of the Ge epilayers. It is also a unique study in the initial growth of Ge epitaxy; the start point of the experiments includes Stranski–Krastanov mode in which the Ge wet layer is initially formed and later the growth is developed to form nuclides. Afterwards, a two-dimensional Ge layer is formed from the coalescing of the nuclides. The evolution of the strain from the beginning stage of the growth up to the full Ge layer has been investigated. Material characterization results show that Ge epilayer with 400 nm LT-Ge buffer layer features at least the root mean square (RMS) value and it’s threading dislocation density (TDD) decreases by a factor of 2. In view of the 400 nm LT-Ge buffer layer, the 1000 nm Ge epilayer with HT-Ge growth temperature of 650 °C showed the best material quality, which is conducive to the merging of the crystals into a connected structure eventually forming a continuous and two-dimensional film. After increasing the thickness of Ge layer from 900 nm to 2000 nm, Ge surface roughness decreased first and then increased slowly (the RMS value for 1400 nm Ge layer was 0.81 nm). Finally, a high-temperature annealing process was carried out and high-quality Ge layer was obtained (TDD=2.78 × 107 cm−2). In addition, room temperature strong photoluminescence (PL) peak intensity and narrow full width at half maximum (11 meV) spectra further confirm the high crystalline quality of the Ge layer manufactured by this optimized process. This work highlights the inducing, increasing, and relaxing of the strain in the Ge buffer and the signature of the defect formation.

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