http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Ping-An Liu,Meng-Jun Wang,Lu Wang,Jun Wang,Ting Wang 대한화학회 2019 Bulletin of the Korean Chemical Society Vol.40 No.4
In this study, novel carbon nanotube (CNT) and transition-metal oxides (TMOs) nanoparticle catalysts were prepared and their effects on the thermal decomposition of potassium perchlorate (KP) were investigated. Nanocatalysts have been widely studied because of their excellent properties, such as the high surface energies of nanoparticles and their ease of agglomeration adversely affect their catalytic performances. Good dispersion is the key to good nanocatalytic activity. The composite catalysts were prepared by loading a nanocatalyst on CNTs; this improves nanoparticle dispersion, promotes electron transfer during the reaction, and increases the catalytic effect. Different types of CNT-based composite catalysts and their corresponding single nanocatalysts were each added to KP. The effects of the catalysts on the thermal decomposition of KP were studied using thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The activity of each catalyst was evaluated on the basis of the changes in the thermal decomposition peaks and the apparent decomposition heats. The results show that the activity of a composite catalyst in KP thermal decomposition is much higher than that of its corresponding single nanocatalyst.
Wang, Hong-Ping,Zhang, You-Bo,Yang, Xiu-Wei,Zhao, Da-Qing,Wang, Ying-Ping The Korean Society of Ginseng 2016 Journal of Ginseng Research Vol.40 No.4
Background: Ginsenosides are the characteristic and principal components which manifest a variety of the biological and pharmacological activities of the roots and rhizomes of Panax ginseng (GRR). This study was carried out to qualitatively and quantitatively determine the ginsenosides in the cultivated and forest GRR. Methods: A rapid and sensitive ultra-high-performance liquid chromatography coupled with diode-array detector and quadrupole/time of flight tandem mass spectrometry (UPLC-DAD-QTOF-MS/MS) was applied to the qualitative analysis of ginsenosides and a 4000 QTRAP triple quadrupole tandem mass spectrometer (HPLC-ESI-MS) was applied to quantitative analysis of 19 ginsenosides. Results: In the qualitative analysis, all ingredients were separated in 10 min. A total of 131 ginsenosides were detected in cultivated and forest GRR. The method for the quantitative determination was validated for linearity, precision, and limits of detection and quantification. 19 representative ginsenosides were quantitated. The total content of all 19 ginsenosides in the forest GRR were much higher than those in the cultivated GRR, and were increased with the growing ages. Conclusion: This newly developed analysis method could be applied to the quality assessment of GRR as well as the distinction between cultivated and forest GRR.
Adverse effect of DEHP exposure on the serum insulin level of Balb/c mice
Jing Wang,Jinquan Li,Kashif Rafiq Zahid,Kun Wang,Yan Qian,Ping Ma,Shumao Ding,Xu Yang,Xianliang Wang,Xianliang Wang,Xu Yang 대한독성 유전단백체 학회 2016 Molecular & cellular toxicology Vol.12 No.1
Di(2-ethylhexyl) phthalate (DEHP) is a common indoor pollutant in the world, which may cause lots of harmful effects in human including diabetes according to epidemiological studies. To explore the underlying role of DEHP in diabetes-like symptoms, Balb/c mice were chose to be the experimental animals in this paper. They were separated as eight groups as follows: (1) saline+normal diet (vehicle control), (2) 10 mg/kg.day DEHP+normal diet, (3) 50 mg/kg.day DEHP+normal diet, (4) 250 mg/kg.day DEHP+normal diet, (5) streptozotocin (STZ)+high fat diet (diabetes model), (6) 10 mg/kg.day DEHP+ STZ+high fat diet, (7) 50 mg/kg.day DEHP+STZ +high fat diet, (8) 250 mg/kg.day DEHP+STZ+high fat diet. The biomarkers of this experiment include four groups: (1) general indicates: body weight and drinking water, (2) blood biomarkers: serum insulin and fasting glucose, (3) pathological examination: pancreas section and kidney section, and (4) biomarkers of oxidative stress: reactive oxygen species (ROS) and malondialdehyde (MDA) in liver cells. Our study results demonstrate that: (1) at our treatment levels DEHP cannot directly induce diabetes, but reduce serum insulin level in DEHP-exposed non-STZ-treated animals, (2) pathological examination finds that these is a dose-dependent damage in the pancreas in DEHP- exposed STZ-treated groups, and (3) the oxidative mechanism may be involved in this pathological process.
Yu-Shuai Wang,Yin-Ping Jin,Wei Gao,Sheng-Yuan Xiao,Yu-Wei Zhang,Pei-He Zheng,Jia Wang,Jun-Xia Liu,Cheng-He Sun,Ying-Ping Wang 고려인삼학회 2016 Journal of Ginseng Research Vol.40 No.3
Background: Ginsenosides are the major effective ingredients responsible for the pharmacological effects of ginseng. Malonyl ginsenosides are natural ginsenosides that contain a malonyl group attached to a glucose unit of the corresponding neutral ginsenosides. Methods: Medium-pressure liquid chromatography and semipreparative high-performance liquid chromatography were used to isolate purified compounds and their structures determined by extensive one-dimensional- and two-dimensional nuclear magnetic resonance (NMR) experiments. Results: A new saponin, namely malonyl-ginsenoside Re, was isolated from the fresh flower buds of Panax ginseng, along with malonyl-ginsenosides Rb1, Rb2, Rc, Rd. Some assignments for previously published ¹H- and <SUP>13</SUP>C-NMR spectra were found to be inaccurate. Conclusion: This study reports the complete NMR assignment of malonyl-ginsenoside Re, Rb₁, Rb₂, Rc, and Rd for the first time.
Ping Wang,Chendong Zhao,Yun Zhang,Jing Li,Yongping Gao 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.2
In order to meet the increasing needs of the hybrid energy source system for electric vehicles, which demand bidirectional power flow capability with a wide-voltage-conversion range, a bidirectional three-level DC-DC converter and some control strategies for hybrid energy source electric vehicles are proposed. The proposed topology is synthesized from Buck and Boost three-level DC-DC topologies with a high voltage-gain and non-extreme duty cycles, and the bidirectional operation principle is analyzed. In addition, the inductor current ripple can be effectively reduced within the permitted duty cycle range by the coordinated control between the current fluctuation reduction and the non-extreme duty cycles. Furthermore, benefitting from duty cycle disturbance control, series-connected capacitor voltages can also be well balanced, even with the discrepant rise and fall time of power switches and the somewhat unequal capacitances of series-connected capacitors. Finally, experiment results of the bidirectional operations are given to verify the validity and feasibility of the proposed converter and control strategies. It is shown to be suitable for hybrid energy source electric vehicles.
Ping Hu,Guo-An Luo,Zhong-Zhen Zhao,Wan Wang,Qing Wang,Zhi-Hong Jiang 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.10
This study systematically investigated the retention behavior of seven neutral ginsenosides Rg₁, Re, Rf, Rb₁, Rb₂, Rc, Rd, and an acidic ginsenoside R0, the major pharmacologically active components of Radix Ginseng with RP-HPLC. The effects of solvent, pH value, ionic strength of the mobile phase, and column temperature were investigated using an octadecylsiloxane-bonded silica gel column. Based on the ginsenosides’ retention characteristics, the concentration of acetonitrile and the gradient of the mobile phase needed to maintain the baseline separation of the major neutral ginsenosides in Radix Ginseng were theoretically predicted. Furthermore, the ionic strength of mobile-phase necessary to achieve good resolution of the neutral ginsenosides and acidic ginsenosides was carefully investigated. According to the results of the quantitative analysis of ginsenosides in eight batches of ginseng samples from different sources, the developed HPLC technique may be a valuable tool for the quality assessment of Radix Ginseng.
Wang Gui-Ping,Xue Xiao-Min,Yang Xing-hong,Chen Ru,Han Xue-Ping 한국식물생명공학회 2022 Plant biotechnology reports Vol.16 No.2
In recent years, with the global climate change, the intensity, frequency and duration of drought have increased significantly, which has become the main limiting factor for agricultural development in many areas. Glycine betaine (GB) is an effec- tive stress-resistant substance. In this experiment, the effects of the genetic engineering of GB synthesis on photosynthetic apparatus of tobacco under drought stress were studied using transgenic tobacco (T) accumulating GB and wild-type tobacco (K326, WT). Potted tobaccos were subjected to drought stress (controlled irrigation, 25 °C ± 1 °C, a relative humidity: 75–80%) for 9 days, photosynthetic gas exchange parameters, chlorophyll a fluorescence, structure of chloroplast and thyla- koid membrane, and protein function of thylakoid membrane were examined under different drought stress time (days). The results showed that T tobacco could accumulate GB and the accumulated GB improved the resistance of the photosynthetic apparatus to drought stress. Under drought stress, the damage of chloroplast and thylakoid lamellae in T tobacco was less than that in WT tobacco, the accumulation of GB in T tobacco could maintain the stability of thylakoid membrane, improved the unsaturated fatty acid index (IUFA) of thylakoid membrane lipid, increased the contents of digalactosyl diacylglycerol (DGDG) and phosphatidylglycerol (PG), and decreased the ratio of monogalactosyl diaylglycerol (MGDG) to DGDG. In addition, under drought stress, the accumulation of GB in T tobacco alleviated the photo-inhibition of PSII, and the increase of xanthophyll cycle de-epoxidation may be one of the reasons for the enhancement of PSII function.