Effect of oxidizing treatment on electrocatalytic activity of boron‑doped amorphous carbon thin films

Chen‑Song Wang,Ni Suo,Hao Huang,Ai‑min Wu,Guo‑Zhong Cao,Gui‑Feng Zhang 한국탄소학회 2019 Carbon Letters Vol.29 No.5

Boron-doped amorphous carbon (BDAC) thin films with a regular oxygen reduction reaction (ORR) catalytic activity were synthesized in a hot filament chemical vapor deposition device using a mixture of CH4 and H2 as a gas source and B2O3 as a boron source and then oxidized in air at 380–470 °C for 15–75 min. Scanning electron microscope, transmission electron microscope, Raman spectroscopy, X-ray photoelectron spectroscopy, and electrochemical tests were used to characterize the physical and electrochemical properties of the BDAC catalysts. It was concluded that the BDAC catalyst oxidized at 450 °C for 45 min showed the best ORR catalytic activity in alkaline medium. The oxygen reduction potential and the transfer electron number n, respectively, are − 0.286 V versus Ag/AgCl and 3.24 from the rotating disk electrode experiments. The treated carbon film has better methanol resistance and stability than the commercial Pt/C catalyst.

沿岸航行 船舶用 DBS 受信시스템의 開發

朱貴營,崔朝天 木浦海洋大學校 2001 論文集 Vol.9 No.1

This study is motivated to develop a tracking antenna system for receive the DBS signal from koreasat in the coast sailing ship. Therefore, this system is made to small size, light weight and simple operation which is must to low cost system for popularization of small-size ship and adaptive possibilities with very useful on a ship in the coast of Korea peninsula. The antenna mount structure is a compact size and easy operation to the Az-axis type which is operated by step motor. The antenna unit is a domestic made plate type of micro-strip array and ship's moving detection is using the gyro sensor for ship's moving control. We are used to algorithm of step-tracking and ship's moving compensation. The compensation is adapted to the closed loop control method by detection from gyro sensor. The system is consisted of MCS-51 micro processor, ADC, comparative amplifier, step motor driver, mechanism and assemble program.

New Method of Designing Controller for Uncertain Diff erential-Diff erence Systems and Application to Time-Delay Operational Amplifi er System

Ke Jian,Chung-Cheng Chen,Yen-Ting Chen,Gui-hong Lin 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.6

This study combines the feedback linearization method and our recent researches of Chen electrical unifying approach to propose a global tracking controller design for nonlinear uncertain diff erential-diff erence systems with time delay. One example, which cannot be solved by the fi rst paper on the almost disturbance decoupling problem, is presented in this study to show the essential points that the tracking performance is easily solved by the proposed approach. The study applies Chen electrical unifying approach to take the place of using the disorganized virtual ground technique and the Kirchhoff ’s law for those traditional approaches. In order to show its signifi cant practicability, the study has fi rstly designed an easy-to-implement adder and a time-delay circuit, and an unstable time-delay operational amplifi er control system based on the Chen electrical unifying approach, and then has proposed a stable controller.

Surface modification of poly(vinylidene fluoride) membrane with hydrophilic and anti-fouling performance via a two-step polymerization

Gui-E Chen,Li Sun,Zhen-Liang Xu,Hu Yang,Hui-Hong Huang,Yan-Jun Liu 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.12

The surface modification of poly (vinylidene fluoride) (PVDF) membrane was performed via a two-step polymerization reactions. Poly (acrylic acid) (PAAc) was first grafted onto the membrane surface for the preparation of PVDF-g-PAAc membrane, and then poly (ethylene glycol) 200 (PEG 200) was immobilized on the membrane surface by the esterification reaction for the fabrication of PVDF-g-PEGA membrane. Attenuated total reflectance (ATR) FTIR, X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), and protein adsorption, water flux, water content and dynamic contact angle were conducted to characterize the structures and performance of the resultant PVDF membranes. The experimental results showed that the adsorption of bovine serum albumin (BSA) on the PVDF-g-PEGA membrane decreased about 80% when the grafting ratio reached to 15 wt%, compared with the pristine PVDF membrane. Moreover, the water contact angle of the membrane dropped to 60.5o, while the membrane pore sizes remained little changed.

Effects of High Pressure on pH, Water-binding Capacity and Textural Properties of Pork Muscle Gels Containing Various Levels of Sodium Alginate

Chen, Cong-Gui,Borjigin, Gerelt,Jiang, Shao-Tong,Tadayuki, Nishiumi,Atsushi, Suzuki Asian Australasian Association of Animal Productio 2006 Animal Bioscience Vol.19 No.11

The objective of this study was to investigate the effects of sodium alginate (SA) and pressurization levels on pH, water-binding and textural properties of pork muscle gels (PMG) containing salt. Ground lean pork with 1.0% NaCl and a given amount of SA (0.25, 0.5, 0.75 and 1.0%, respectively), was pressurized to 100, 200 or 300 MPa and subsequently gelled by heating. Results showed that addition of SA into pork muscle enhanced water-holding capacity (WHC) of PMG (p<0.05) as SA increased from 0.25% to 1.0%, with pH slightly increased (p>0.05). A decrease (p<0.05) was observed in all textural parameters (hardness, cohesiveness, springiness and chewiness). Pressurization had no effect on the tendency of WHC to increase or the decrease of the textural parameters. However, the effectiveness of pressurization to enhance textural properties of PMG was significant at some SA levels, especially ${\geq}200MPa$ and at ${\leq}0.75%$ SA levels. Different combinations of pressure and SA levels could bring about variation in textural properties of PMG while SA enhanced WHC of pork muscle. The multiformity of the texture will open up a wide range of technological possibilities for the manufacture of pork-based restructured low-fat products.

Prevalence and Genotype Distribution of Human Papillomavirus Infections in Women Attending Hospitals in Chaozhou of Guangdong Province

Chen, Qiang,Luo, Zhao-Yun,Lin, Min,Lin, Qi-Li,Chen, Chan-Yu,Yang, Chun,Xie, Long-Xu,Li, Hui,Zheng, Jia-Kun,Yang, Li-Ye,Ju, Gui-Zhi Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.4

Background: Human papillomavirus (HPV) infection is the main cause of cervical cancer. Limited epidemiologic data of HPV prevalence are available for women attending hospitals in southern China. This study aimed to evaluate the profiles of HPV infection and cytology status in gynecological outpatients in Chaozhou City. Methods: A total of 2833 eligible women were enrolled. The HPV GenoArray test was used for HPV detection and genotyping. Nearly one half of the HPV positive women received liquid-based cytology test. Logistic regression analysis was performed to assess the predictable effects of age and genotype for categories of abnormal cytology. Results: The prevalence of overall, high-risk, and low-risk HPV infection were 24.5%, 19.5% and 8.4%, respectively. A U-shaped age-specific prevalence curve was observed in overall HPV and high-risk HPV, but not in low-risk HPV, which declined with age increasing. The 6 most common high-risk HPV type in descending order, were types 52, 16, 58, 18, 68, and 33. Age and HPV genotype were both important determinants of abnormal cytology incidence, the older women (>45 years) and those infected with HPV type 16 and/or 18 having the highest risk for abnormal cytology. Conclusion: Our findings support the hypothesis that second-generation HPV prophylactic vaccines including HPV-52 and -58 may offer higher protection for women residing in Chaozhou and neighboring cities in Guangdong.

Analysis on the Dynamics of Spatial Distribution Pattern of Mixed Spider Populations in Dongting Lake Plain Paddy field

Chen Kang-Gui,Joo-Pil Kim 한국거미연구소 2002 한국거미 Vol.18 No.1

书法美育视角下义务教育阶段书法教育刍论

천구이롱(Gui-Rong Chen) 한국서예학회 2023 서예학연구 Vol.42 No.-

서예교육은 중국의 초등학교 의무교육에서 綱要에 해당하는 부분으로 현재 이 단계의 서예교육은 학생들의 낮은 경필력, 붓글씨 미교육 부족 등의 현실적인 문제가 있다. 본고는 현재 서예교육 현황, 경필서예교육과 붓서예교육의 공통성과 차이점, 「中小学书法教育指导纲要」및 학생들의 학습수요 측면을 다루었다. 핵심 관점은 경필서예교육과 붓서예교육이 다르다는 것이다. 경필서예는 규범, 미관, 실용을 주요 목표로 삼아야 하며, 붓서예는 미교육과 실천을 결합해야 한다. 아울러 기술을 너무 중시하고 미학에 대한 중시를 소홀히 해서는 안된다는 것을 주장하였다.이 연구를 통해 현재 의무교육 단계의 서예교육에 대한 몇 가지 아이디어를 제공할 수 있을 것이다. Calligraphy education is an important part of compulsory education. At present, there are some practical problems in calligraphy education, such as poor writing ability and insufficient aesthetic education of calligraphy.This paper mainly studies the current situation of calligraphy education, the commonality and difference between calligraphy education and calligraphy art education, the Outline of Calligraphy Education in Primary and Secondary Schools and the students' learning needs.The key point is that calligraphy art education and writing education are different. Hard pen writing should aim at standardization, beauty and practicality.The conclusion can be used as a reference for calligraphy education in the current compulsory education stage.

Cordycepsmilitaris polysaccharide triggers apoptosis and G0/G1 cell arrest in cancer cells

Cheng Chen,Mei-LinWang,Chao Jin,Huijuan Chen,Shao-Hui Li,Shu-Ying Li,Xing-Fan Dou,Jun-Qiang Jia,Zhong-Zheng Gui 한국응용곤충학회 2015 Journal of Asia-Pacific Entomology Vol.18 No.3

Although many studies have shown the antitumor properties of Cordyceps militaris (artificial cultivated from Bombyx mori pupa) polysaccharides, little is known regarding the mechanism of its effects. This study was conducted to determine the mechanism of antitumor effects of C. militaris polysaccharide extract by evaluating apoptosis rate and cell cycle progression status in human liver cancer cell SMMC-7721, stomach cancer cell BGC-823 and breast cancer cell MCF-7. Results showed that C. militaris polysaccharides inhibited proliferation of SMMC-7721, BGC-823 and MCF-7 cells with an IC50 of 192 ± 23.2 μg/mL, 237 ± 12.7 μg/mL and 165 ± 16.3 μg/mL, respectively. We also found that C. militaris polysaccharides at increasing concentrations induced apoptosis dose dependently in those cancer cells: apoptosis rates were 48.3%, 59.4% and 70.9% for SMMC-7721, 41.3% and 57.0%, 72.2% for BGC-823 and 61.3%, 66.9% and 80.6% for MCF-7 at 110, 156 and 323 mg/mL of C. militaris polysaccharides, respectively. C. militaris polysaccharides arrested SMMC-7721, BGC-823 and MCF-7 cells at G0/G1 and G2/M phases with corresponding decrease in S-phase. This study suggests that C. militaris polysaccharides may exert its antitumor effects in those cancer cells by suppressing its growth, arresting the G0/G1-phase, reducing DNA synthesis and inducing apoptosis.

Energy Efficient with Network Coding Multipath Routing Algorithm in Wireless Sensor Networks

Chao Gui,Hua Chen,Baolin Sun,Ying Song 보안공학연구지원센터 2014 International Journal of Future Generation Communi Vol.7 No.6

Network coding is a new paradigm in data transport and promises to change many aspects of wireless sensor network (WSN). Thanks to the recently developed network coding techniques, a high-throughput low-complexity hierarchical protocol can be facilitated due to the multiple-source relay-based data transmissions built on the network coding schemes, especially for the data communications between the source node and destination node. In this paper, we propose an Energy efficient that carefully couples Network coding and Multipath routing algorithm in Wireless Sensor Networks (ENM-WSN). Through an analytical study, we provide guidance on how to choose parameters in our scheme and demonstrate that the scheme is efficient in both multipath and energy consumption. We also present an algorithm for deciding the network coding scheme for a node to further reduce energy consumption by minimizing redundant packet transmissions. Simulation results show that, with the proposed energy efficient with network coding in WSN multipath routing protocol (ENM-WSN), energy consumption, packet delivery ratio, and network lifetime can be improved in most of cases. It is an available approach to multipath routing decision.