Molecular Dynamics Simulation to Investigate the Rake Angle Effects on Nanometric Cutting of Single Crystal Ni3Al

Rui-cheng Feng,Yong-nian Qi,Zong-xiao Zhu,Wen-yuan Song,Hai-yan Li,Mao-mao Wang,Zhi-yuan Rui,Feng-shou Gu 한국정밀공학회 2020 International Journal of Precision Engineering and Vol.21 No.4

Molecular dynamics, an eff ective method to gain an insight into nanometric behaviour of materials, was employed to studythe nano-cutting behaviour of single crystal Ni 3 Al in nanometric scale. In this paper, comparisons were made for compressive/tensile stress, subsurface damage and surface roughness with three rake angles of a diamond tool. Subsurface damage waspartitioned by region and studied with work hardening in detail. A model for precise characterization of surface roughnesswas established with consideration of local surface fl uctuation. Simulation results showed that the chip thickness increasedas rake angle changed from negative to positive, and the boundary formed between tensile and compressive stress was inconsistent with the glide direction of stacking fault. Subsurface damage decreased as the increase of rake angle, and regularglide planes of stacking faults were found in front of the cutting tool. Further, the pinned dissociated 1/2 < 110 > superpartialdislocation with anti-phase boundary was demonstrated. The model was tested and characterized by implanted pits onperfect surface. Results showed that surface roughness can be well characterized, and an evident discrepancy was observedamong three rake angles, especially for 30° rake angle, which showed an distinct smooth surface compared with the others.

Template Synthesis of Nitrogen-Doped Short Tubular Carbons with Big Inner Diameter and their Application in Electrochemical Sensing

Rui Cheng,Qiong Zou,Xiaohua Zhang,Chunhui Xiao,Longfei Sun,Jinhua Chen 대한화학회 2014 Bulletin of the Korean Chemical Society Vol.35 No.8

Nitrogen-doped short tubular carbons (N-STCs) with big inner diameter have been successfully synthesized via carbonization of polydopamine (PDA) wrapped halloysite nanotubes (HNTs). The obtained N-STCs have average length of 0.3 μm with big inner diameter (50 nm), thin wall (2-3 nm) and large surface area (776 m2 g−1), and show excellent electrochemical properties. As an example in electrochemical applications, N-STCs were used to electrochemically detect hydrogen peroxide (H2O2) and glucose. The results showed that the N-STCs modified glassy carbon (N-STCs/GC) electrode had much better analytical performance (lower detection limit and wider linear range) compared to the acid-treated carbon nanotubes (AO-CNTs) based GC electrode. The unique structure endows N-STCs the enhanced electrochemical performance and promising applications in electrochemical sensing.

Construction of Z-scheme W18O49/NiAl-LDH heterojunction with photothermal effect for photocatalytic reduction of CO2

Cheng Xia,Rui-Tang Guo,Zhen-rui Zhang,Chen-yuan Fan,Yu-zhe Liu,Yu-cheng Lin,Chu-fan Li,Wei-Guo Pan 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.128 No.-

Recently, the photocatalytic CO2 reduction technology is an effective solution to remit the energy crisis. Inorder to improve the photocatalytic performance, Z-scheme W18O49/NiAl-LDH composite catalysts wereprepared by hydrothermal method. Fortunately, the prepared catalysts revealed excellent photocatalyticperformance under the simulated sunlight, and CO and CH4 could be detected in the reduction products. WO/LDH-0.5 catalyst possessed the optimal activity, with CO and CH4 yield of 37.09 and 8.01 lmol g-1h1separately, which were 7.9 and 3.6 times that of NiAl-LDH monomer. In addition, W18O49 endowedW18O49/NiAl-LDH catalysts with photothermal effect, which raised the surface temperature andfacilitated the catalytic reaction. Meanwhile, the Z-scheme heterojunction composed of flower-likeNiAl-LDH and urchin-like W18O49 accelerated the separation of photoexcited carriers and enhanced theredox ability. Through a series of characterizations and investigations, this work is promising to breaknew ground for the design of photocatalysts with photothermal effect.

OPTIMAL IMPULSE AND REGULAR CONTROL STRATEGIES FOR PROPORTIONAL REINSURANCE PROBLEM

RUI-CHENG, YANG,KUN-HUI, LIU,BING, XIA 한국전산응용수학회 2005 Journal of applied mathematics & informatics Vol.18 No.1

We formulate a stochastic control problem on proportional reinsurance that includes impulse and regular control strategies. For the first time we combine impulse control with regular control, and derive the expected total discount pay-out (return function) from present to bankruptcy. By relying on both stochastic calculus and the classical theory of impulse and regular controls, we state a set of sufficient conditions for its solution in terms of optimal return function. Moreover, we also derive its explicit form and corresponding impulse and regular control strategies.

Template Synthesis of Nitrogen-Doped Short Tubular Carbons with Big Inner Diameter and their Application in Electrochemical Sensing

Cheng, Rui,Zou, Qiong,Zhang, Xiaohua,Xiao, Chunhui,Sun, Longfei,Chen, Jinhua Korean Chemical Society 2014 Bulletin of the Korean Chemical Society Vol.35 No.8

Nitrogen-doped short tubular carbons (N-STCs) with big inner diameter have been successfully synthesized via carbonization of polydopamine (PDA) wrapped halloysite nanotubes (HNTs). The obtained N-STCs have average length of $0.3{\mu}m$ with big inner diameter (50 nm), thin wall (2-3 nm) and large surface area ($776m^2g^{-1}$), and show excellent electrochemical properties. As an example in electrochemical applications, N-STCs were used to electrochemically detect hydrogen peroxide ($H_2O_2$) and glucose. The results showed that the N-STCs modified glassy carbon (N-STCs/GC) electrode had much better analytical performance (lower detection limit and wider linear range) compared to the acid-treated carbon nanotubes (AO-CNTs) based GC electrode. The unique structure endows N-STCs the enhanced electrochemical performance and promising applications in electrochemical sensing.

Identification of Prostate Cancer LncRNAs by RNA-Seq

Hu, Cheng-Cheng,Gan, Ping,Zhang, Rui-Ying,Xue, Jin-Xia,Ran, Long-Ke Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.21

Purpose: To identify prostate cancer lncRNAs using a pipeline proposed in this study, which is applicable for the identification of lncRNAs that are differentially expressed in prostate cancer tissues but have a negligible potential to encode proteins. Materials and Methods: We used two publicly available RNA-Seq datasets from normal prostate tissue and prostate cancer. Putative lncRNAs were predicted using the biological technology, then specific lncRNAs of prostate cancer were found by differential expression analysis and co-expression network was constructed by the weighted gene co-expression network analysis. Results: A total of 1,080 lncRNA transcripts were obtained in the RNA-Seq datasets. Three genes (PCA3, C20orf166-AS1 and RP11-267A15.1) showed a significant differential expression in the prostate cancer tissues, and were thus identified as prostate cancer specific lncRNAs. Brown and black modules had significant negative and positive correlations with prostate cancer, respectively. Conclusions: The pipeline proposed in this study is useful for the prediction of prostate cancer specific lncRNAs. Three genes (PCA3, C20orf166-AS1, and RP11-267A15.1) were identified to have a significant differential expression in prostate cancer tissues. However, there have been no published studies to demonstrate the specificity of RP11-267A15.1 in prostate cancer tissues. Thus, the results of this study can provide a new theoretic insight into the identification of prostate cancer specific genes.

Optimal impulse and regular control strategies for proportionalreinsurance problem

Yang Rui-cheng,Liu Kun-hui,Xia Bing 한국전산응용수학회 2005 Journal of applied mathematics & informatics Vol.18 No.1-2

We formulate a stochastic control problem on proportional reinsurance that includes impulse and regular control strategies. For the first time we combine impulse control with regular control, and derive the expected total discount pay-out (return function) from present to bankruptcy. By relying on both stochastic calculus and the classical theory of impulse and regular controls, we state a set of sufficient conditions for its solution in terms of optimal return function. Moreover, we also derive its explicit form and corresponding impulse and regular control strategies.

Morphological Factors and Cardiac Doses in Whole Breast Radiation for Left-sided Breast Cancer

Guan, Hui,Dong, Yuan-Li,Ding, Li-Jie,Zhang, Zi-Cheng,Huang, Wei,Liu, Cheng-Xin,Fu, Cheng-Rui,Zhu, Jian,Li, Hong-Sheng,Li, Miao-Miao,Li, Bao-Sheng Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.7

Background: To investigate the impact of the breast size, shape, maximum heart depth (MDH), and chest wall hypotenuse (the distance connecting middle point of the sternum and the length of lung draw on the selected transverse CT slice) on the volumetric dose to heart with whole breast irradiation (WBI) of left-sided breast cancer patients. Materials and Methods: Fifty-three patients with left-sided breast cancer undergoing adjuvant intensity-modulated radiotherapy (IMRT) were enrolled in the study. The primary breast size and shape, MHD and DCWH (chest wall hypotenuse) were contoured on radiotherapy (RT) planning CT slices. The dose data of hearts were obtained from the dose-volume histograms (DVHs). Data were analyzed by one-way analysis of variance (ANOVA), Student's t-test and linear regression analysis. Results: Breast size was independent of heart dose, whereas breast shape, MHD and DCWH were correlated with heart dose. The shapes of breasts were divided into four types, as the flap type, hemisphere type, cone type and pendulous type with heart mean dose being $491.8{\pm}234.6cGy$, $752.7{\pm}219.0cGy$, $620.2{\pm}275.7cGy$, and $666.1{\pm}238.0cGy$, respectively. The flap type of breasts shows a strong statistically reduction in heart dose, compared to others (p=0.008 for V30 of heart). DCWH and MHD were found to be the most important parameters correlating with heart dose in WBI. Conclusions: More attention should be paid to the heart dose of non-flap type patients. The MHD was found to be the most important parameter to correlate with heart dose in tangential WBI, closely followed by the DCWH, which could help radiation oncologists and physicsts evaluate heart dose and design RT plan in advance.

Field Emission from TiO2/Ti Nanotube Array Films Modified with Carbon Nanotubes

Cheng-Wei Wang,Rui-Sheng Guo,Jian-Biao Chen,Yan Li,Jian Wang,Wei-Min Liu 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.6

Well-aligned TiO2/Ti nanotube array films were synthesized by using anodic oxidation of titanium in 0.5-wt% HF and were modified with carbon nanotubes (CNTs) assembled by using catalyzed chemical vapor deposition (CVD) at 650 ˚C. The morphology and the quality of the films were assessed with field emission scanning electron microscopy and Raman spectrometry (325 nm). The field emission characteristics of such TiO2/Ti nanostructures were investigated before and after being modified with CNTs. The results show that the TiO2/Ti nanotube arrays possess a moderate turn-on electric field of 7.4 V/µm, a field emission current density of 2.7 mA/cm2 at 23 V/µm. It is noteworthy that the turn-on field of the TiO2/Ti nanotube arrays modified with CNTs is decreased significantly to 1.3 V/µm, and the emission current density is increased to 10 mA/cm2 at 5.6 V/µm. This novel structure shows high emission efficiency as a field emitter. Well-aligned TiO2/Ti nanotube array films were synthesized by using anodic oxidation of titanium in 0.5-wt% HF and were modified with carbon nanotubes (CNTs) assembled by using catalyzed chemical vapor deposition (CVD) at 650 ˚C. The morphology and the quality of the films were assessed with field emission scanning electron microscopy and Raman spectrometry (325 nm). The field emission characteristics of such TiO2/Ti nanostructures were investigated before and after being modified with CNTs. The results show that the TiO2/Ti nanotube arrays possess a moderate turn-on electric field of 7.4 V/µm, a field emission current density of 2.7 mA/cm2 at 23 V/µm. It is noteworthy that the turn-on field of the TiO2/Ti nanotube arrays modified with CNTs is decreased significantly to 1.3 V/µm, and the emission current density is increased to 10 mA/cm2 at 5.6 V/µm. This novel structure shows high emission efficiency as a field emitter.

Low-Rank Representation-Based Image Super-Resolution Reconstruction with Edge-Preserving

( Rui Gao ),( Deqiang Cheng ),( Jie Yao ),( Liangliang Chen ) 한국인터넷정보학회 2020 KSII Transactions on Internet and Information Syst Vol.14 No.9

Low-rank representation methods already achieve many applications in the image reconstruction. However, for high-gradient image patches with rich texture details and strong edge information, it is difficult to find sufficient similar patches. Existing low-rank representation methods usually destroy image critical details and fail to preserve edge structure. In order to promote the performance, a new representation-based image super-resolution reconstruction method is proposed, which combines gradient domain guided image filter with the structure-constrained low-rank representation so as to enhance image details as well as reveal the intrinsic structure of an input image. Firstly, we extract the gradient domain guided filter of each atom in high resolution dictionary in order to acquire high-frequency prior information. Secondly, this prior information is taken as a structure constraint and introduced into the low-rank representation framework to develop a new model so as to maintain the edges of reconstructed image. Thirdly, the approximate optimal solution of the model is solved through alternating direction method of multipliers. After that, experiments are performed and results show that the proposed algorithm has higher performances than conventional state-of-the-art algorithms in both quantitative and qualitative aspects.