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      • SCIESCOPUSKCI등재

        Discrimination of American ginseng and Asian ginseng using electronic nose and gas chromatography-mass spectrometry coupled with chemometrics

        Cui, Shaoqing,Wu, Jianfeng,Wang, Jun,Wang, Xinlei The Korean Society of Ginseng 2017 Journal of Ginseng Research Vol.41 No.1

        Background: American ginseng (Panax quinquefolius L.) and Asian ginseng (Panax ginseng Meyer) products, such as slices, have a similar appearance, but they have significantly different prices, leading to widespread adulteration in the commercial market. Their aroma characteristics are attracting increasing attention and are supposed to be effective and nondestructive markers to determine adulteration. Methods: The aroma characteristics of American and Asian ginseng were investigated using gas chromatography-mass spectrometry(GC-MS) and an electronic nose (E-nose). Their volatile organic compounds were separated, classified, compared, and analyzed with different pattern recognition. Results: The E-nose showed a good performance in grouping with a principle component analysis explaining 94.45% of variance. A total of 69 aroma components were identified by GC-MS, with 35.6% common components and 64.6% special ingredients between the two ginsengs. It was observed that the components and the number of terpenes and alcohols were markedly different, indicating possible reasons for their difference. The results of pattern recognition confirmed that the E-nose processing result is similar to that of GC-MS. The interrelation between aroma constituents and sensors indicated that special sensors were highly related to some terpenes and alcohols. Accordingly, the contents of selected constituents were accurately predicted by corresponding sensors with most $R^2$ reaching 90%. Conclusion: Combined with advanced chemometrics, the E-nose is capable of discriminating between American and Asian ginseng in both qualitative and quantitative angles, presenting an accurate, rapid, and nondestructive reference approach.

      • SCOPUSKCI등재

        Synthesis of Hβ (core)/SAPO-11 (shell) Composite Molecular Sieve and its Catalytic Performances in the Methylation of Naphthalene with Methanol

        Wang, Xiaoxiao,Guo, Shaoqing,Zhao, Liangfu Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.12

        $H{\beta}$ (core)/SAPO-11 (shell) composite molecular sieve was synthesized by the hydrothermal method in order to combine the advantages of $H{\beta}$ and SAPO-11 for the methylation of naphthalene with methanol. For comparison, the mechanical mixture was prepared through the blending of $H{\beta}$ and SAPO-11. The physicochemical properties of $H{\beta}$, SAPO-11, the composite and the mechanical mixture were characterized by various characterization methods. The characterization results indicated that $H{\beta}$/SAPO-11 composite molecular sieve exhibited a core-shell structure, with the $H{\beta}$ phase as the core and the SAPO-11 phase as the shell. The pore diameter of the composite was between that of $H{\beta}$ and SAPO-11. The composite had fewer acid sites than $H{\beta}$ and mechanical mixture while more acid sites than SAPO-11. The experimental results indicated that the composite exhibited high catalytic performances for the methylation of naphthalene with methanol.

      • KCI등재

        The catalytic performance of methylation of naphthalene with methanol over SAPO-11 zeolites synthesized with different Si content

        Shaoqing Guo,Liangfu Zhao,Xiaoxiao Wang,Fang Guo,Xianxian Wei,Zhenmin Liu,Wei Zhang 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.7

        A series of SAPO-11 zeolites with different Si contents were prepared by hydrothermally synthesized method. They were characterized by ICP, XRD, SEM, FT-IR, N2 adsorption-desorption, NH3-TPD and 29Si MAS NMR, and evaluated by the methylation of naphthalene with methanol to 2,6-dimethylnaphthalene (2,6-DMN). According to XRD and SEM results, the crystallinity of SAPO-11 sample increased with increase of the Si content until the SiO2/Al2O3 ratio was up to 0.2. However, a reduction in the crystallinity was observed with further increase of the Si content of the synthesis. N2 adsorption-desorption results showed that all the samples possessed micropores and secondary mesopores. SAPO-11 sample with SiO2/Al2O3 ratio of 0.2 exhibited the largest secondary mesopores size distributions. NH3-TPD and 29Si MAS NMR showed that the Si content was incorporated into the framework affecting not only the acid sites but also the acid strength of SAPO-11. SAPO-11 with SiO2/Al2O3 ratio of 0.2 presented the high catalytic performances for the methylation of naphthalene, which was mainly attributed to the amount of secondary mesopores in the SAPO-11 zeolite.

      • KCI등재

        Effects of N-Acetylcysteine on Nicotinamide Dinucleotide Phosphate Oxidase Activation and Antioxidant Status in Heart, Lung, Liver and Kidney in Streptozotocin-Induced Diabetic Rats

        Shaoqing Lei,Zhengyuan Xia,Huimin Liu,Hong Yu,Hui Wang,Yanan Liu 연세대학교의과대학 2012 Yonsei medical journal Vol.53 No.2

        Purpose: Hyperglycemia increases reactive oxygen species (ROS) and the resulting oxidative stress plays a key role in the pathogenesis of diabetic complications. Nicotinamide dinucleotide phosphate (NADPH) oxidase is one of the major sources of ROS production in diabetes. We, therefore, examined the possibility that NADPH oxidase activation is increased in various tissues, and that the antioxidant N-acetylcysteine (NAC) may have tissue specific effects on NADPH oxidase and tissue antioxidant status in diabetes. Materials and Methods: Control (C) and streptozotocin-induced diabetic (D) rats were treated either with NAC (1.5 g/kg/day) orally or placebo for 4 weeks. The plasma, heart, lung, liver, kidney were harvested immediately and stored for biochemical or immunoblot analysis. Results: levels of free 15-F2t-isoprostane were increased in plasma, heart, lung, liver and kidney tissues in diabetic rats, accompanied with significantly increased membrane translocation of the NADPH oxidase subunit p67phox in all tissues and increased expression of the membrane-bound subunit p22phox in heart, lung and kidney. The tissue antioxidant activity in lung, liver and kidney was decreased in diabetic rats, while it was increased in heart tissue. NAC reduced the expression of p22phox and p67phox, suppressed p67phox membrane translocation, and reduced free 15-F2t-isoprostane levels in all tissues. NAC increased antioxidant activity in liver and lung, but did not significantly affect antioxidant activity in heart and kidney. Conclusion: The current study shows that NAC inhibits NADPH oxidase activation in diabetes and attenuates tissue oxidative damage in all organs, even though its effects on antioxidant activity are tissue specific.

      • KCI등재

        Synthesis of Hβ (core)/SAPO-11 (shell) Composite Molecular Sieve and its Catalytic Performances in the Methylation of Naphthalene with Methanol

        Xiaoxiao Wang,Shaoqing Guo,Liangfu Zhao 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.12

        Hβ (core)/SAPO-11 (shell) composite molecular sieve was synthesized by the hydrothermal method in order to combine the advantages of Hβ and SAPO-11 for the methylation of naphthalene with methanol. For comparison, the mechanical mixture was prepared through the blending of Hβ and SAPO-11. The physicochemical properties of Hβ, SAPO-11, the composite and the mechanical mixture were characterized by various characterization methods. The characterization results indicated that Hβ/SAPO-11 composite molecular sieve exhibited a core-shell structure, with the Hβ phase as the core and the SAPO-11 phase as the shell. The pore diameter of the composite was between that of Hβ and SAPO-11. The composite had fewer acid sites than Hβ and mechanical mixture while more acid sites than SAPO-11. The experimental results indicated that the composite exhibited high catalytic performances for the methylation of naphthalene with methanol.

      • KCI등재

        Analysis of Load Characteristic and Contact Patch Characteristic of Support Insert Run-Flat Tire under Zero-Pressure Condition

        Zang Liguo,Wang Xingyu,Wu Chongyou,Teng Fei,Shaoqing Yang 한국자동차공학회 2021 International journal of automotive technology Vol.22 No.5

        Support insert run-flat tire is a kind of safety tire based on common tire structure. It has the advantages of simple structure, easy disassembly and strong bearing capacity. However, when driving under zero-pressure condition, it can not meet the requirements of heavy load, high mobility and long-distance. Aiming at this problem, the finite element model is established. The load and contact patch characteristics of the model are simulated by ABAQUS. The radial stiffness curve and the contact pressure distribution under zero-pressure are obtained. The results show that the radial stiffness curve presents a certain nonlinearity in the sidewall loading stage. When the insert contacts the tire, it is approximately linear. The contact pressure distribution cloud diagram under zero-pressure condition shows that there is warpage. The tire test bench was set up and the relevant test scheme was formulated. The radial stiffness curve and the footprint of the support insert run-flat tire under zeropressure condition were obtained. The research results show that the simulation and test results are in good agreement. This research is of great significance to the performance analysis of whole support insert run-flat tire under zero- pressure condition.

      • KCI등재

        Imidazole derivatives for efficient organic light-emitting diodes

        Ye Shaofeng,Zhuang Shaoqing,Pan Biao,Guo Runda,Wang Lei 한국정보디스플레이학회 2020 Journal of information display Vol.21 No.3

        Since the first development of organic light-emitting diodes (OLEDs) in 1987, imidazole derivatives, mainly including phenanthroimidazole (PI) and benzimidazole (BI), have increasingly attracted attention. Their strong electron-withdrawing properties make them suitable for emitters, hosts, and electron-transporting materials (ETMs). In this review, an overview of the recent developments regarding OLEDs based on imidazole derivatives, especially the relationship between the molecule structure and the device performance as fluorescent and host materials, is given.

      • KCI등재

        Geochemical baseline and distribution of cobalt, manganese, and vanadium in the Liao River Watershed sediments of China

        Chunye Lin,Jing Wang,Shaoqing Liu,Mengchang He,Xitao Liu 한국지질과학협의회 2013 Geosciences Journal Vol.17 No.4

        The quantitative contamination assessment of toxic elements in sediments is a challenge due to the lack of their geochemical background or baseline levels and sediment heterogeneity. Eighty-eight sediment samples were collected in the Liao River Watershed (LRW) and analyzed for Co, Mn, V, Sc, Fe, Al, and sediment properties. The average background levels, geochemical baseline levels (GBL), and geochemical baseline functions of Co,Mn, and V in the sediments were obtained using statistical and geochemical methodologies. The concentrations of Co, Mn, and V were 0.86 to 23.40, 105.9 to 1771.6, and 6.47 to 153.30 mg/kg, respectively. The average background levels and GBLs were 7.2 and 14.4mg/kg for Co, 422 and 762 mg/kg for Mn, and 35.4 and 59.0 mg/kg for V. The linear correlation of Co, Mn, and V with particle-size proxy elements (normalizers) Sc, Fe, and Al was statistically significant with probability (p-value) <0.001 level, showing that Fe,Al, and Sc can be used as particle-size proxy elements to develop the GBFs of Co, Mn, and V. The spatial distribution of the sampling sites with the concentrations of Co, Mn, and V either outlied or greater than GBLs may be related to industry and mine distribution,showing the impact of human activities on the contents of Co, Mn, and V in the LRW sediments. The procedure in the study can be used to estimate GBLs and construct GBFs of toxic elements in other watershed sediments on the world in order to manage sediment quality. The quantitative contamination assessment of toxic elements in sediments is a challenge due to the lack of their geochemical background or baseline levels and sediment heterogeneity. Eighty-eight sediment samples were collected in the Liao River Watershed (LRW) and analyzed for Co, Mn, V, Sc, Fe, Al, and sediment properties. The average background levels, geochemical baseline levels (GBL), and geochemical baseline functions of Co,Mn, and V in the sediments were obtained using statistical and geochemical methodologies. The concentrations of Co, Mn, and V were 0.86 to 23.40, 105.9 to 1771.6, and 6.47 to 153.30 mg/kg, respectively. The average background levels and GBLs were 7.2 and 14.4mg/kg for Co, 422 and 762 mg/kg for Mn, and 35.4 and 59.0 mg/kg for V. The linear correlation of Co, Mn, and V with particle-size proxy elements (normalizers) Sc, Fe, and Al was statistically significant with probability (p-value) <0.001 level, showing that Fe,Al, and Sc can be used as particle-size proxy elements to develop the GBFs of Co, Mn, and V. The spatial distribution of the sampling sites with the concentrations of Co, Mn, and V either outlied or greater than GBLs may be related to industry and mine distribution,showing the impact of human activities on the contents of Co, Mn, and V in the LRW sediments. The procedure in the study can be used to estimate GBLs and construct GBFs of toxic elements in other watershed sediments on the world in order to manage sediment quality.

      • KCI등재

        The effects of MCM-41’s calcination temperature on the structure and hydrodenitrogenation over NiW catalysts

        Fang Guo,Zegang Qiu,Liangfu Zhao,Shaoqing Guo,Xian-Xian Wei,Xiaoxiao Wang,Hongwei Xiang 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.11

        MCM-41 was calcined at 500, 560, 600 or 650 oC. It was used as support for NiW catalysts of hydrodenitro-genation (HDN) for quinoline in order to investigate the influences of the MCM-41’s calcination temperature on thestructure and the HDN performance of NiW catalysts. The NiW catalysts were characterized by XRD, N2 adsorption-desorption, XPS, Raman, HRTEM and Py-IR techniques. The results showed that the surface area (SBET), the averagepore diameter (Dp) and the pore volume (Vp) of the MCM-41 increased with increase of the MCM-41’s calcinationtemperature. The high SBET , Dp and Vp were beneficial for the high dispersion of W species, the formation of appropriatenature of W species and acid sites on the catalysts. The HDN activity followed the order of NiW-650≈NiW-600>NiW-560>NiW-500, while the relative selectivity of HDN pathways was similar for all the catalysts.

      • KCI등재

        Identification of floral aromatic volatile compounds in 29 cultivars from four groups of Osmanthus fragrans by gas chromatography–mass spectrometry

        Jianxin Fu,Dan Hou,Yiguang Wang,Chao Zhang,Zhiyi Bao,Hongbo Zhao,Shaoqing Hu 한국원예학회 2019 Horticulture, Environment, and Biotechnology Vol.60 No.4

        Osmanthus fragrans Lour. is a popular aromatic ornamental plant and its fl owers are used to enhance the color and fragrance of food. In this study, we analyzed the volatiles of 29 cultivars from all four groups of O. fragrans using a solid-phase microextraction (SPME) technique and gas chromatography–mass spectrometry (GC–MS). We identifi ed 41 volatile organic components that were distributed over fi ve diff erent compound classes, with the majority of the volatile components being dominated by alcohols, ketones, and terpenes, which accounted for 56.6–95.06% of the total volatiles in all tested materials except ‘Zao Yingui’. In ‘Zao Yingui’, alcohols, ketones, and terpenes accounted for only 48.19% of the total volatiles. The diversity of the volatile compounds and their relative contents varied among the four groups and cultivars within each group. The major volatile compounds were α-ionone, β-ionone, 2H-β-ionone, linalool, trans -linalool oxide, cis -linalool oxide, epoxy linalool, geraniol ( Z )-ocimene, and γ-decalactone in all tested cultivars, while nerol and ( Z )-3-hexenyl butanoic acid ester were abundant in several cultivars. The 29 cultivars were classifi ed into fi ve clusters in a hierarchical cluster analysis based on their fl oral volatile compounds. The cultivars of diff erent sexes (male vs. hermaphrodite) had no signifi cant diff erences in the relative contents of the major volatile compounds. This study provides valuable information for understanding the chemical composition of the volatile compounds of O. fragrans fl owers as well as a theoretical basis for the origin, development, and application of modern cultivars of O. fragrans.

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