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      • KCI등재

        Antioxidant and Antigenotoxic Activities of Ethanol Extracts from Rhus chinensis Mill Leaves

        Zhenyu Qiu,Mingli Tang,Guanjun Deng,Hao Yang,Xuan Zhang,Shengwei Huang,Lifang Wu 한국식품과학회 2014 Food Science and Biotechnology Vol.23 No.4

        Ethanol extracts were obtained from Rhuschinensis Mill (RCM) leaves and used for antioxidant andantigenotoxic activity assays. IC50 values in DPPH assayswere 15.96, 18.83, 20.43, 27.93, 37.43, 46.21, and 141.84μg/mL for TPP, IPE, LLE, Vc, CE, BHT, and Trolox. Similar results were obtained using ABTS and FRAPassays. In vivo testing showed strong antioxidant activitiesthat were positively correlated with polyphenol contents. Leaf tissue contained abundant polyphenols, and more than10 phenolic compounds were detected in extracts. Quantitative results showed that quercetin-3-rhamnoside(26.4±0.76 mg/g of extract) was the most abundantingredient, followed by hyperoside (15.2±0.42 mg/g ofextract), quercetin (1.5±0.07mg/g of extract), and kaempferol(0.48±0.05 mg/g of extract). This study increases theknowledge for possible uses of forest by-products as asubstitute for gallnuts.

      • KCI등재

        Production of biodiesel from soybean oil catalyzed by attapulgite loaded with C4H5O6KNa catalyst

        Fengxian Qiu,Bin Ye,Yihuai Li,Chuanjia Sun,Zhenyu Zhao,Teng Ma,Dongya Yang 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.7

        Biodiesel is a green, safe, renewable alternative fuel, which is of great significance to solving the problem of energy shortage and environmental pollution. A series of solid base catalysts were prepared with the support of attapulgite (ATP), the load of C4H5O6KNa by impregnation method, and were used to catalyze transesterification of soybean oil with methanol to biodiesel. The activities of prepared catalysts were investigated compared to pure ATP. The optimal conditions for the catalyst preparation were investigated: molar ratio of Na : ATP was 1.7 : 1 and calcination temperature was 400 oC. The prepared catalysts were characterized by several techniques such as Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, N2 adsorption-desorption measurements,X-ray diffraction and the Hammett indicator method. The prepared solid base catalyst can be separated from reaction system effectively and easily. The effects of the molar ratio of methanol to oil, reaction temperature and amount of catalyst on the biodiesel yield were investigated. The experimental results showed that a 22 : 1 molar ratio of methanol to oil, 10.0% of catalyst amount, 65 oC of reaction temperature and 3.0 h of reaction time gave the best results. The catalyst has longer lifetime and maintained sustained activity after being used for five cycles.

      • Tool Monitoring System Using Vibration and Current Signals

        Zhennan Wei,Zhenyu Qiu,Qian Huang,Yundi Chu 제어로봇시스템학회 2022 제어로봇시스템학회 국제학술대회 논문집 Vol.2022 No.11

        The on-line monitoring of tool wear condition plays an important role in reducing production cost and improving production efficiency. Firstly, this paper introduces the wear mechanism of cutting tools, the detection method of tool wear, and the commonly used signal processing technology. Secondly, through the experiments of various cutting parameters, various characteristic information in different grinding processes is obtained, and the correlation analysis is carried out, and the characteristic values related to the grinding process are obtained. Then, the corresponding BP neural network model is established. Finally, according to the characteristics of the CNC machine monitoring system, Cortex_A15 is selected as the core of the monitoring system, and the neural network algorithm is applied to the hardware board which is more economical than the PC to save the production cost.

      • KCI등재

        Complex CAD surface shape design using semantic features

        Fengbei Cheng,Zhenyu Liu,Guifang Duan,Chan Qiu,Bing Yi,Jianrong Tan 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.7

        To a large extent, the success of the product shape design depends on whether the geometric modeling systems can satisfy more andmore complicated design demands in the engineering field. This paper proposes a shape design method based on semantic features forcomplex CAD surface. By the proposed method, we can easily meet the complicated design requirements, since the semantic can effectivelyrepresent the design intent. We discussed three aspects in shape design using semantic features, which are semantic design demandsof the target surface, geometric constraints in accordance with semantic features, and surface shape deformation under the geometricconstraints, respectively. The basic semantic features of geometric models drive the deformation of the target surface shape bychanging the related constraint, and the desirable features are added to the CAD surface shape. The examples of the car shape design arepresented to verify the effectives of our method.

      • High-yield production of few-layer boron nanosheets for efficient electrocatalytic N<sub>2</sub> reduction

        Fan, Qun,Choi, Changhyeok,Yan, Chao,Liu, Yongchao,Qiu, Jieshan,Hong, Song,Jung, Yousung,Sun, Zhenyu The Royal Society of Chemistry 2019 Chemical communications Vol.55 No.29

        <P>We report ambient electrochemical N2 fixation at low overpotentials by using two-dimensional (2D) β-boron. The metal-free catalyst afforded both an excellent NH3 yield rate and faradaic efficiency, approximately two times higher than those of bulk boron. We found that several binding sites, especially those involving icosahedral boron in the 2D material, can indeed catalyze N2 reduction efficiently with strong N2 adsorption, thus benefiting initial activation.</P>

      • KCI등재

        Comparison between Craniospinal Irradiation and Limited-Field Radiation in Patients with Non-metastatic Bifocal Germinoma

        Bo Li,Wenyi Lv,Chunde Li,Jiongxian Yang,Jiajia Chen,Jin Feng,Li Chen,Zhenyu Ma,Youqi Li,Jiayi Wang,Yanwei Liu,Yanong Li,Shuai Liu,Shiqi Luo,Xiaoguang Qiu 대한암학회 2020 Cancer Research and Treatment Vol.52 No.4

        Purpose Whether craniospinal irradiation (CSI) could be replaced by limited-field radiation in non-metastatic bifocal germinoma remains controversial. We addressed the issue based on the data from our series and the literature. Materials and Methods Data from 49 patients diagnosed with non-metastatic bifocal germinoma at our hospital during the last 10 years were collected. The Pediatric Quality of Life Inventory 4.0 was used to evaluate health-related quality of life (HRQOL). Additionally, 81 patients identified from the literature were also analyzed independently. Results In our cohort, 34 patients had tumors in the sellar/suprasellar (S/SS) plus pineal gland (PG) regions and 15 in the S/SS plus basal ganglia/thalamus (BG/T) regions. The median follow-up period was 52 months (range, 10 to 134 months). Our survival analysis showed that patients treated with CSI (n=12) or whole-brain radiotherapy (WBRT; n=34) had comparable disease-free survival (DFS; p=0.540), but better DFS than those treated with focal radiotherapy (FR; n=3, p=0.016). All 81 patients from the literature had tumors in the S/SS+PG regions. Relapses were documented in 4/45 patients treated with FR, 2/17 treated with whole-ventricle irradiation, 0/4 treated with WBRT, and 1/15 treated with CSI. Survival analysis did not reveal DFS differences between the types of radiation field (p=0.785). HRQOL analysis (n=44) in our cohort found that, compared with S/SS+PG germinoma, patients with BG/T involvement had significantly lower scores in social and school domains. However, HRQOL difference between patients treated with CSI and those not treated with CSI was not significant. Conclusion In patients with non-metastatic bifocal germinoma, it is rational that CSI could be replaced by limited-field radiation. HRQOL in patients with BG/T involvement was poorer.

      • Carbon-supported Ni nanoparticles for efficient CO <sub>2</sub> electroreduction

        Jia, Mingwen,Choi, Changhyeok,Wu, Tai-Sing,Ma, Chen,Kang, Peng,Tao, Hengcong,Fan, Qun,Hong, Song,Liu, Shizhen,Soo, Yun-Liang,Jung, Yousung,Qiu, Jieshan,Sun, Zhenyu Royal Society of Chemistry 2018 Chemical Science Vol.9 No.47

        <▼1><P>Carbon-coated Ni nanoparticles supported on N-doped carbon enable efficient electroreduction of CO<SUB>2</SUB> to CO comparable to single Ni sites.</P></▼1><▼2><P>The development of highly selective, low cost, and energy-efficient electrocatalysts is crucial for CO<SUB>2</SUB> electrocatalysis to mitigate energy shortages and to lower the global carbon footprint. Herein, we first report that carbon-coated Ni nanoparticles supported on N-doped carbon enable efficient electroreduction of CO<SUB>2</SUB> to CO. In contrast to most previously reported Ni metal catalysts that resulted in severe hydrogen evolution during CO<SUB>2</SUB> conversion, the Ni particle catalyst here presents an unprecedented CO faradaic efficiency of approximately 94% at an overpotential of 0.59 V, even comparable to that of the best single Ni sites. The catalyst also affords a high CO partial current density and a large CO turnover frequency, reaching 22.7 mA cm<SUP>–2</SUP> and 697 h<SUP>–1</SUP> at –1.1 V (<I>versus</I> the reversible hydrogen electrode), respectively. Experiments combined with density functional theory calculations showed that the carbon layer coated on Ni and N-dopants in carbon material both play important roles in improving catalytic activity for electrochemical CO<SUB>2</SUB> reduction to CO by stabilizing *COOH without affecting the easy *CO desorption ability of the catalyst.</P></▼2>

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