• Title/Summary/Keyword: Zhan

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Electrochemical Investigation of Acetaminophen with a Carbon Nano-tube Composite Film Electrode

  • Li, Chunya;Zhan, Guoqing;Yang, Qingdan;Lu, Jianjie
    • Bulletin of the Korean Chemical Society
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    • v.27 no.11
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    • pp.1854-1860
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    • 2006
  • Electrochemical behaviors of acetaminophen at a muti-wall carbon nano-tube composite film modified glassy carbon electrode were investigated by cyclic voltammetry, linear sweep voltammetry and chronocoulometry. Compared with that obtained at the unmodified electrode, the peak currents were enhanced significantly, and the oxidation peak shifted towards more negative potential with the reduction peak shifted positively. The peak-to-peak separation turned narrow, and suggested that the reversibility was improved greatly. Experimental parameters, such as scan rate, pH and accumulation conditions were optimized. It was found that a maximum current response can be obtained at pH = 5.0 after accumulation at -0.50 V for 80 s. The oxidation peak current was found to be linearly related to acetaminophen concentration over the range of $5.0{\times}10^{-7}\;\sim\;1.0{\times}10^{-4}$ mol $L^{-1}$ with a detection limit of $5.0{\times}10^{-8} $mol $L^{-1}$. A convenient and sensitive electrochemical method was developed for the determination of acetaminophen in a commercial paracetamol oral solution. Its practical application demonstrated that it has good selectivity and high sensitivity.

Antiinflammatory Constituents from the Roots of Smilax bockii warb.

  • Xu Jing;Li Xian;Zhang Peng;Li Zhan-Lin;Wang Yi
    • Archives of Pharmacal Research
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    • v.28 no.4
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    • pp.395-399
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    • 2005
  • From $70\%$ ethanol extract of the roots of Smilax bockii warb., seven flavonoids, kaempferol (1), $kaempferol-7-O-\beta-D-glucopyranoside$ (2), quercetin (3), isorhamnetin (4), (+)-dihydro­kaempferol (5), engeletin (6), isoengeletin (7), and $n-butyl-\beta-D-fructopyranoside$ (8), caffeic acid n-butyl ester (9) were isolated and identified by means of chemical and spectroscopic. Compounds 2, 4, and 6-9 were isolated for the first time from the roots of S. bockii and compounds 2, 8, and 9 were firstly isolated from the genus Smilax. In addition, using the SEAP (Secreted alkaline phosphatase) assay system, we investigated the in vitro anti-inflammatory activity of the $70\%$ ethanol extract of the roots of S. bockii, which showed moderate activity in inhibiting $TNF-\alpha-induced NF-{\kappa}B$ activation with an $IC_{50}$ value of $166.6 {\mu}g/mL$.

Effect of Heat Treatment on the Lipophillic Pigments of Fresh Green Tea Liquor

  • Lu, Jian-Liang;Dong, Zhan-Bo;Pan, Shun-Shun;Lin, Chen;Zheng, Xin-Qiang;Devajit, Borthakur;Liang, Yue-Rong
    • Food Science and Biotechnology
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    • v.18 no.3
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    • pp.682-688
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    • 2009
  • Changes in lipophillic pigments concentration and its relation to color of fresh green tea liquor during heat treatment were studied. The results showed liquor greenness decreased markedly with extension of incubation time at $55^{\circ}C$, while the brightness and yellowness changed a little. Significant increase in 'a' and 'b' values of tea liquor was observed at $95^{\circ}C$. Color change of liquor at $55^{\circ}C$ was accompanied by a decrease in the level of chlorophylls, lutein and neoxanthin, and an increase in the pheophytins and ${\beta}-carotene$ levels. However, all pigments except ${\beta}-carotene$ decreased with time extension at $95^{\circ}C$. Significant correlation was found between pigments and color difference index. The browning of fresh green tea liquor was attributed to vicissitudes of lipophillic pigments during heat treatment, especially to the change of chlorophylls/pheophytins ratio. Result also showed addition of $Zn^{2+}$ at 1.6 ${\mu}mol/L$ could partially alleviate the decrease in greenness during heat treatment.

Coding-based Storage Design for Continuous Data Collection in Wireless Sensor Networks

  • Zhan, Cheng;Xiao, Fuyuan
    • Journal of Communications and Networks
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    • v.18 no.3
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    • pp.493-501
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    • 2016
  • In-network storage is an effective technique for avoiding network congestion and reducing power consumption in continuous data collection in wireless sensor networks. In recent years, network coding based storage design has been proposed as a means to achieving ubiquitous access that permits any query to be satisfied by a few random (nearby) storage nodes. To maintain data consistency in continuous data collection applications, the readings of a sensor over time must be sent to the same set of storage nodes. In this paper, we present an efficient approach to updating data at storage nodes to maintain data consistency at the storage nodes without decoding out the old data and re-encoding with new data. We studied a transmission strategy that identifies a set of storage nodes for each source sensor that minimizes the transmission cost and achieves ubiquitous access by transmitting sparsely using the sparse matrix theory. We demonstrate that the problem of minimizing the cost of transmission with coding is NP-hard. We present an approximation algorithm based on regarding every storage node with memory size B as B tiny nodes that can store only one packet. We analyzed the approximation ratio of the proposed approximation solution, and compared the performance of the proposed coding approach with other coding schemes presented in the literature. The simulation results confirm that significant performance improvement can be achieved with the proposed transmission strategy.

A Study of Dynamic Forecast on Port Container Handling Capacity (항만 컨테이너 처리능력의 통계적 예측에 관한 연구)

  • Feng, Zhan-Qing;Lee, Su-Ho
    • Journal of Navigation and Port Research
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    • v.26 no.2
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    • pp.161-166
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    • 2002
  • In view of the great disparity between forecasts of Shanghai port container handling capacity and its real results, we choose a dynamic forecast method by the causality model dynamic compensation to predict Shanghai port container handling capacity. And we forecast Shanghai port container handling capacity by using this method. We have made a satisfactory achievement, which provides a more reliable and practical way to forecast container handling capacity.

ACCELERATED AGING USING $FOCAS^{(R)}$-A BURNER BASED SYSTEM SIMULATING AN ENGINE

  • Bykowski, B.B.;Bartley, G.J.J.;Webb, C.C.;Zhan, R.;Burrahm, R.W.
    • International Journal of Automotive Technology
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    • v.7 no.3
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    • pp.245-249
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    • 2006
  • Accelerated aging of engine exhaust system components such as catalytic converters are traditionally performed using an engine/dynamometer test stand. $SwRI^{(R)}'s\;FOCAS^{(R)}$ system reduces or eliminates many of the engine based aging limitations. This paper will describe several studies. These include: 1) replication of engine based catalyst aging cycles with added precision and dependability; 2) catalyst aging with and without lubricating oil effects; 3) effects of lubricant phosphorus on catalyst performance; and 4) the potential to thermally age components beyond the capabilities of engine based systems. The first study includes the development of the SwRI FOCAS system to run programmed aging conditions with or without lubricating oil. A description of the subsystems is given. The second two studies used the SwRI FOCAS system to age catalysts. One study compared thermal-only aging using of the SwRI FOCAS system with equivalent aging on a traditional engine/dynamometer test stand. The other study examined the effect on catalyst performance of two lubricating oils containing different levels of phosphorus, and compared the results to field data generated using the same oils in a fleet of vehicles.

Discovery of Eurytrema Eggs in Sediment from a Colonial Period Latrine in Taiwan

  • Yeh, Hui-Yuan;Cheng, Chieh-fu Jeff;Huang, ChingJung;Zhan, Xiaoya;Wong, Weng Kin;Mitchell, Piers D.
    • Parasites, Hosts and Diseases
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    • v.57 no.6
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    • pp.595-599
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    • 2019
  • In this study we take a closer look at the diseases that afflicted Japanese police officers who were stationed in a remote mountainous region of Taiwan from 1921 to 1944. Samples were taken from the latrine at the Huabanuo police outpost, and analyzed for the eggs of intestinal parasites, using microscopy and ELISA. The eggs of Eurytrema sp., (possibly E. pancreaticum), whipworm and roundworm were shown to be present. True infection with Eurytrema would indicate that the policemen ate uncooked grasshoppers and crickets infected with the parasite. However, false parasitism might also occur if the policemen ate the uncooked intestines of infected cattle, and the Eurytrema eggs passed through the human intestines. These findings provide an insight into the diet and health of the Japanese colonists in Taiwan nearly a century ago.

Differential Change in the Prevalence of the Ascaris, Trichuris and Clonorchis infection Among Past East Asian Populations

  • Zhan, Xiaoya;Yeh, Hui-Yuan;Shin, Dong Hoon;Chai, Jong-Yil;Seo, Min;Mitchell, Piers D.
    • Parasites, Hosts and Diseases
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    • v.57 no.6
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    • pp.601-605
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    • 2019
  • As we learn more about parasites in ancient civilizations, data becomes available that can be used to see how infection may change over time. The aim of this study is to assess how common certain intestinal parasites were in China and Korea in the past 2000 years, and make comparisons with prevalence data from the 20th century. This allows us to go on to investigate how and why changes in parasite prevalence may have occurred at different times. Here we show that Chinese liver fluke (Clonorchis sinensis) dropped markedly in prevalence in both Korea and China earlier than did roundworm (Ascaris lumbricoides) and whipworm (Trichuris trichiura). We use historical evidence to determine why this was the case, exploring the role of developing sanitation infrastructure, changing use of human feces as crop fertilizer, development of chemical fertilizers, snail control programs, changing dietary preferences, and governmental public health campaigns during the 20th century.

Opportunistic Spectrum Access with Discrete Feedback in Unknown and Dynamic Environment:A Multi-agent Learning Approach

  • Gao, Zhan;Chen, Junhong;Xu, Yuhua
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.10
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    • pp.3867-3886
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    • 2015
  • This article investigates the problem of opportunistic spectrum access in dynamic environment, in which the signal-to-noise ratio (SNR) is time-varying. Different from existing work on continuous feedback, we consider more practical scenarios in which the transmitter receives an Acknowledgment (ACK) if the received SNR is larger than the required threshold, and otherwise a Non-Acknowledgment (NACK). That is, the feedback is discrete. Several applications with different threshold values are also considered in this work. The channel selection problem is formulated as a non-cooperative game, and subsequently it is proved to be a potential game, which has at least one pure strategy Nash equilibrium. Following this, a multi-agent Q-learning algorithm is proposed to converge to Nash equilibria of the game. Furthermore, opportunistic spectrum access with multiple discrete feedbacks is also investigated. Finally, the simulation results verify that the proposed multi-agent Q-learning algorithm is applicable to both situations with binary feedback and multiple discrete feedbacks.

An Exploratory Study on the Effects of Entrepreneurial Expectancy of China's Entrepreneur upon Start-up Business and Growth Intentions (중국기업가의 창업에 대한 기대가 창업 및 성장의도에 미치는 영향에 관한 탐색적 연구)

  • Chung, Dae-Yong;Zhan, Xi
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.11
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    • pp.4881-4887
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    • 2011
  • The research purposes is apply to the expectation theory for the China's entrepreneurs want to know the relations model among the entrepreneurial expectancy, start-up business and expect growth. The entrepreneurial expectancy is defined expectation about entrepreneurial establishment, start-up business and expect growth intentions are defined entrepreneur's lead consider. According to the study, all of hypothesis have been suggested. In other words, expectation about entrepreneurial establishment, start-up business and expect growth effects and start-up business show the mediated effect in the research.