Chemical Vapor Deposition Growth of Graphene Domains Across the Cu Grain Boundaries

Yang Wang,Yu Cheng,Yunlu Wang,Shuai Zhang,Chen Xu,Xuewei Zhang,Miao Wang,Yang Xia,Qunyang Li,Pei Zhao,Hongtao Wang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.08

Many aspects in the chemical vapor deposition (CVD) growth of graphene remain unclear such as its behavior near the catalyst grain boundaries. Here we investigate the CVD growth mechanism of graphene across the Cu grain boundaries using unidirectional aligned graphene domains, which simplifies the analysis of both graphene and Cu to a large extent. We found that for a graphene domain grown across the Cu grain boundary, the domain orientation is determined by the Cu grain where the domain nucleation center is located, and the Cu grain boundary will not change the growth behavior for this graphene domain. This growth mechanism is consistent with the Custep-attached nucleation and edge-attachment-limited growth mechanism for H-terminated graphene domains and will provide more guidance for the synthesis of high-quality graphene with less domain boundaries.

Long-chain alcohols derived from the microalga Monoraphidium

Yang, Xuewei,Dai, Xin,Zhang, Rui,Shao, Cong,Geng, Shu,Chen, Guangyi,Liu, Xianhua,Wang, Guangyi Techno-Press 2013 Advances in energy research Vol.1 No.2

This study was to investigate the composition and characteristics of long-chained alcohols extracted from the algal strain Monoraphidium 3s35. The production of biomass was optimized using different cultivation methods. Under the aerated growth condition, this strain yielded up to 37.26% extracts of dry weight and $576mgL^{-1}$ biomass. The major compounds of the extracts are mainly long-chained alcohols (89.24%), with carbon chain length ranging from 12 to 20. Interestingly, or the long-chained alcohols, 3-(2-Methoxyethyl)-1-nonanol, 3,7,11,15-Tetramethyl-2-hexadecen-1-ol and oleyl alcohol accounted for 53.68%, 23.45%, and 12.11%, respectively. Because of their amphipathic nature, these long-chained alcohols have been widely used in bioenergy production and cosmetics industry. Furthermore, Monoraphidium 3s35 produced 9.73% of $C_{17}$ and $C_{20}$ alkanes, which can be used as an important supplement for the petrodiesel-like fuel.

Tilt Angle Measurement Based on Arrayed Eddy Current Sensors

Xuewei Chao,Yang Li,Jing Nie 한국자기학회 2016 Journal of Magnetics Vol.21 No.4

Eddy current (EC) sensor works based on the electromagnetic induction principle and has been widely applied in the industrial testing and evaluation due to its robustness and environmental adaptability. Meanwhile, tilt angle measurement is mainly based on the laser or visual method, which is strict with the measurement environment and not suitable for the industrial applications. In this paper, a novel tilt angle measurement method based on arrayed EC sensors is proposed. Both the simulation and experiments indicate that the measured error is approximately linear with tilt angle and the accuracy after compensation is 0.25°. In conclusion, this research cannot only broaden the scope of EC application, but also overcome the shortcomings of existing angle measurement methods.

Disturbed-entropy: A simple data quality assessment approach

Yang Li,Xuewei Chao,Sezai Ercisli 한국통신학회 2022 ICT Express Vol.8 No.3

From the perspective of information value, we proposed a simple and effective approach to assess data quality, called disturbed-entropy. In specific, considering image classification task, the existing samples per category are statistically represented as a pixel prototype, which is used to disturb the unseen samples. Then, the entropy of disturbed image is calculated based on predicted probability. Both the numerical and visual experiments are conducted to show the effect. In case of same data budget, the performance comparison based on selected good and bad data is significant and consistent. This work attempts to gain insight into data quality and redundancy.

Biodistribution of a Promising Probiotic, Bifidobacterium longum subsp. longum Strain BBMN68, in the Rat Gut

Lv, Yang,Qiao, Xuewei,Zhao, Liang,Ren, Fazheng The Korean Society for Microbiology and Biotechnol 2015 Journal of microbiology and biotechnology Vol.25 No.6

Bifidobacterium longum subsp. longum BBMN68, isolated from centenarians in Guangxi, China, has been proved to be a promising probiotic strain for its health benefits. In this study, the biodistribution of this strain in the rat gut was first investigated using the quantitative realtime PCR assay and propidium monoazide. Strain-specific primers were originally designed based on the BBMN68 genome sequence. Healthy rats were orally inoculated with either a single dose of BBMN68 (10¹⁰ colony-forming units/kg), or with one dose per day for 7 days and bacterial concentrations were analyzed in detail from the intestinal contents and feces of four different gut locations, including stomach, small intestine, colon, and rectum. Results indicated that strain BBMN68 could overcome the rigors of passage through the upper gastrointestinal tract and transiently accumulate in the colon, even though survival in the stomach and small intestine was not high. A good level of BBMN8 could stay in vivo for 72 h following a 7-day oral administration, and a daily administration is suggested for a considerable and continuous population of BBMN68 to be maintained in the host intestine.

Genetic parameter estimation for reproductive traits in QingYu pigs and comparison of carcass and meat quality traits to Berkshire×QingYu crossbred pigs

Luo Jia,Yang Yiting,Liao Kun,Liu Bin,Chen Ying,Shen Linyuan,Chen Lei,Jiang An’an,Liu Yihui,Li Qiang,Wang Jinyong,Li Xuewei,Zhang Shunhua,Zhu Li 아세아·태평양축산학회 2020 Animal Bioscience Vol.33 No.8

Objective: The QingYu pig is well known for its excellent meat quality attributes in Sichuan province, China. In order to improve its production efficiency, the determination of genetic factors contributing to quantifiable economic traits of livestock is important. Moreover, the cross-breeding of QingYu pigs with western breeds possessing strong growth attributes is an efficient way to improve the performance of this breed. Methods: Here, the genetic parameters of several important reproductive traits of QingYu pigs were estimated, include total number born (TNB), number born alive, litter birth weight, individual birth weight, number of piglets weaned, litter weaning weight, and individual weaning weight. The data was analyzed using the ASReml 3.0 software (NSW Inc., Sydney, Australia). Furthermore, the effects of crossing Berkshire with QingYu (BQ) pigs on carcass and meat quality traits, as well as the effects of slaughter weight on carcass and meat quality of BQ were characterized. Results: QingYu pigs exhibited superior reproductive traits. The TNB available to QingYu pigs was more than 8 per parity. The observed repeatability of the reproductive traits of the QingYu pigs was between 0.10 and 0.23. The significantly correlated genetic and phenotypic of reproduction traits were consistent. Interestingly, the BQ pigs exhibited improved carcass quality, with a significant increase in loin muscle area, lean percentage and reduction in sebum percentage. As a result, BQ had higher L45min, lower cooking scores, and lower drip loss. In addition, the loin muscle area, body length, and sebum percentage were significantly higher in 90 and 100 kg animals. Cooking loss showed a significant increase at 80 kg, and marbling increased significantly from 90 kg. Conclusion: The results of this study suggest that QingYu pigs exhibit excellent reproductive properties and heritability of these traits. Crossing with Berkshire is an efficient strategy to improve the carcass and meat quality of QingYu pigs for commercial operations. Furthermore, it appears as though the optimal slaughter weight of BQ pigs is at approximately 90 kg.

Magnetic Shielding Analysis for Arrayed Eddy Current Testing

Jing Nie,Yang Li,Saibo She,Xuewei Chao 한국자기학회 2019 Journal of Magnetics Vol.24 No.2

Arrayed eddy current testing (AECT) has been widely applied in the field of crack detection, displacement measurement and many other fields due to its non-destructive and high efficiency. But the coupling interference of AECT exists objectively and leads to the detection error directly. In this paper, a magnetic shielding layer is proposed to reduce the coupling interference. The relationships between electromagnetic parameters of magnetic shielding material and coupled magnetic field are discussed theoretically. Furthermore, the simulation and experiments are carried out, the results are consistent. It shows that the application of magnetic shielding layer in AECT can reduce the mutual inductance of probe coils and increase the output voltage. Additionally, the most important factor to select material of magnetic shielding layer is the conductivity. Thus, the magnetic shielding layer with large conductivity will be suitable for AECT to promote the testing performance.

Knee Kinetics Responses to Frontal Impact with Active Muscle Function during Vehicle Crash

Sen Xiao,Xuewei Shi,Zhidong Qu,Jikuang Yang 한국정밀공학회 2019 International Journal of Precision Engineering and Vol.20 No.11

Knee joint injury especially under bending and rotation is a seriously outcome of lower limb injuries in car frontal accident. Due to the anatomical structure, knee is observed primarily in injuries of ligaments and muscles especially in extension or bending condition. This study aims to simulate changes of knee injuries among lower extremities under the load impact environment caused by the functionality of active muscle during the emergency braking which is observed in most of crash accidents. This is a full-scale lower extremities injury study combined with a market sold vehicle. To study the injury characteristics, a simplified real car model with whole restraint systems is first established. Then the active muscle signals during braking condition were introduced to the reaction of the leg muscle groups during the loading process, in which the stress distribution will be relocated along the legs. At last, the study targets through the relationships between ligament force/moment and deflection of the knee under real body impact condition are determined. Results show that with the usage of active muscle functionality, the vulnerable area in lower limb will move to the middle of long bones and the deflections in knee joint will become larger. Meanwhile, the forces in all ligaments around the knee will relocate. The study results can explain the source of injury differences between lower limb injury in tests and that in traffic accident statistics. The models and study methods can be employed in the continuous studies of lower limb injuries during car impact.

Study on Load Impedance Matching Characteristics of Magnetic Coupled Resonant Wireless Power Transfer System

Lijiao Gong,Xinheng Li,Xuewei Chao,Yang Li,Hui Li,Hongwei Li 한국자기학회 2017 Journal of Magnetics Vol.22 No.3

The impedance matching problem of magnetic coupled resonant wireless power transfer system based on planar spiral coils is studied in this paper. Taken the coupling factors into account, the relationships between impedance matching, resonant frequency and transfer distance are analyzed. Supported by the simulation analyses and experimental evidences, it is indicated that the optimum matching resistances for transfer power and transfer efficiency are different. In details, the optimal matching resistance for output power decreases with the transfer distance, while that for the transfer efficiency does not vary with transfer distance. Thus, this research provides a valuable reference for the further research on adaptive impedance matching of magnetic coupled resonant wireless power transfer system.

Effect of Distance on Optimum Transfer Efficiency for the Four-coil Magnetic Coupled Resonance System

Lijiao Gong,Xinheng Li,Xuewei Chao,Jing Zuo,Yang Li 한국자기학회 2017 Journal of Magnetics Vol.22 No.3

As known, the variation of distances between the adjacent coils will affect the transfer efficiency in magnetic coupled resonance system. In order to explore the influence of distance on the optimum transfer efficiency, a four-coil magnetic coupled resonance system is established. Based on the mutual inductance coupling theory, the relationship between the transfer efficiency and coupling coefficient is obtained. Supported by the simulation analysis and experimental evidences, it is found that the coupling coefficient k23 (between transmitter and receiver coils) is the most significant factor affecting the transfer efficiency. Under the optimal k23, the transfer efficiency will increase with the coupling coefficient k12 (between driver and transmitter coils). Besides, it will firstly increase and then decrease with the coupling coefficient k34 (between receiver and load coils). Moreover, the theoretical calculation formula of k23 is deduced, which can make a contribution to the optimization of parameters and improvement of transfer efficiency for the four-coil magnetic coupled resonance system.