33 results on '"Lei, Yong"'
Search Results
2. A Non-Uniformity Factor to Assess Fuel/Air Mixing Quality
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Lei-Yong Jiang
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chemistry.chemical_compound ,Quality (physics) ,chemistry ,Environmental engineering ,Industrial research ,Environmental science ,Combustion ,Mixing (physics) ,Methane - Abstract
A practical method to assess quantitatively the uniformity of fuel/air mixing is essential for research and development of advanced low-emission combustion systems. A non-uniformity factor, based on the fuel/air equivalence ratio, is proposed and demonstrated in a simple methane/air venturi mixer. It has two advantages over the unmixedness parameter and uniformity index approaches: it is correlated with the fuel/air mixture combustion property, and the maximum temperature deviation from the designed value caused by fuel/air non-uniformity can be estimated. Because of these, it can be used as a criterion to check fuel/air mixing quality, or as a target for fuel/air mixer design with acceptable maximum temperature deviation., ASME Turbo Expo 2020: Turbomachinery Technical Conference and Exposition, September 21 - 25, 2020, Virtual, Online
- Published
- 2021
3. Regulation of Intrinsic and Extrinsic Apoptotic Pathways in Osteosarcoma Cells Following Oleandrin Treatment
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Yunlong Ma, Bin Zhu, Lei Yong, Chunyu Song, Xiao Liu, Huilei Yu, Peng Wang, Zhongjun Liu, and Xiaoguang Liu
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oleandrin ,osteosarcoma ,apoptosis ,caspases ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Our previous study has reported the anti-tumor effect of oleandrin on osteosarcoma (OS) cells. In the current study, we mainly explored its potential regulation on intrinsic and extrinsic apoptotic pathway in OS cells. Cells apoptosis, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were detected using fluorescence staining and flow cytometry. Caspase-3 activity was detected using a commercial kit. The levels of cytoplasmic cytochrome c, mitochondrial cytochrome c, bcl-2, bax, caspase-9, Fas, FasL, caspase-8 and caspase-3 were detected by Western blotting. z-VAD-fmk was applied to block both intrinsic and extrinsic apoptosis pathways, and cells apoptosis was also tested. Furthermore, we used z-LEHD-fmk and Fas blocking antibody to inhibit intrinsic and extrinsic pathways, separately, and the selectivity of oleandrin on these pathways was explored. Results showed that oleandrin induced the apoptosis of OS cells, which was accompanied by an increase in ROS and a decrease in MMP. Furthermore, cytochrome c level was reduced in mitochondria but elevated in the cytoplasm. Caspase-3 activity was enhanced by oleandrin in a concentration- and time-dependent manner. Oleandrin also down-regulated the expression of bcl-2, but up-regulated bax, caspase-9, Fas, FasL, caspase-8 and caspase-3. In addition, the suppression of both apoptotic pathways by z-VAD-fmk greatly reverted the oleandrin-induced apoptosis. Moreover, the suppression of one pathway by a corresponding inhibitor did not affect the regulation of oleandrin on another pathway. Taken together, we concluded that oleandrin induced apoptosis of OS cells via activating both intrinsic and extrinsic apoptotic pathways.
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- 2016
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4. VPS34 regulates dynamin to determine the endocytosis of mitochondria-targeted zinc oxide nanoparticles in human osteosarcoma cells
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Bao Hai, Shuheng Zhai, Xinyu Dou, Guanping He, Yunlong Ma, Xiaoguang Liu, Lei Bian, Lei Yong, Chenlong Yang, Yu Liu, Xiaoyu Pan, Tianli Mao, Hanwen Zhang, Chuanchao Du, and Fei Jia
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Programmed cell death ,Cell ,Endocytic cycle ,Biomedical Engineering ,Apoptosis ,02 engineering and technology ,Endocytosis ,Cell membrane ,03 medical and health sciences ,Dynamin II ,medicine ,Autophagy ,Humans ,General Materials Science ,030304 developmental biology ,Dynamin ,0303 health sciences ,Osteosarcoma ,Chemistry ,General Chemistry ,General Medicine ,021001 nanoscience & nanotechnology ,Class III Phosphatidylinositol 3-Kinases ,Cell biology ,Mitochondria ,medicine.anatomical_structure ,Cancer cell ,Nanoparticles ,Zinc Oxide ,0210 nano-technology - Abstract
In our previous study, zinc oxide nanoparticles (ZnO NPs) presented satisfying therapeutic effects with cancer cell selectivity in osteosarcoma cells and, thus, have been considered as a potential nanomedicine for human osteosarcoma treatment. However, the poorly investigated internalization process, including their endocytic pathway into tumor cells and intracellular fate, limits the clinical application. Here, we further clarified these aspects. First, ZnO NPs were rapidly internalized by osteosarcoma cells and accumulated in mitochondria, before being entrapped into lysosomes. Second, dynasore (a dynamin inhibitor) was demonstrated to be the most effective in blocking ZnO NP uptake and rescuing ZnO NP-induced osteosarcoma cell autophagic death and apoptosis. Third, we confirmed the key role of dynamin 2 in ZnO NP endocytosis and subsequent autophagic cell death in vitro and in vivo. Furthermore, we proved that VPS34 transferred from cell cytoplasm to cell membrane to interact with dynamin under ZnO NP treatment. Altogether, combined with our previous study, the current research further revealed that ZnO NPs entered human osteosarcoma cells through the VPS34/dynamin 2-dependent endocytic pathway, directly targeting and damaging the mitochondria before being entrapped into the lysosomes, thereby initiating mitophagy-Zn2+-reactive oxygen species-mitophagy axis mediated cell apoptosis.
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- 2021
5. Hybrid organic-inorganic light-emitting diodes based on a polythylenimine interlayer
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Wang RuiXue, Yang Xiaohui, Lei Yong, and Fan Changjun
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chemistry.chemical_classification ,Multidisciplinary ,Materials science ,business.industry ,Polymer ,Cathode ,law.invention ,chemistry ,law ,Electron affinity ,Optoelectronics ,Quantum efficiency ,Work function ,business ,Phosphorescence ,Ultraviolet photoelectron spectroscopy ,Light-emitting diode - Abstract
Implementation of a polyethylenimine ethoxylated (PEIE) interlayer significantly enhances electron injection efficiency from ZnO into light emitting polymers including a blue light emitting polymer with relatively low electron affinity, verified by comparison of current density-voltage characteristics of the electron-only devices with or without a PEIE interlayer. Ultraviolet photoelectron spectroscopy measurements reveal that PEIE forms interfacial dipoles and reduces the work function of ZnO by ca. 1.2 eV, thus facilitating electron injection into light emitting polymers. Neutralized amines rather than protonated amines are responsible for the formation of interfacial dipoles as manifested by N1s core level spectra of the ZnO/PEIE sample. Luminance efficiency of hybrid organic-inorganic light emitting devices employing PEIE interlayer is similar to that of the analogous conventional devices with low work-function metal cathode due to electron injection promoting and hole/exciton-blocking properties of PEIE. Compared to Cs 2 CO 3 , PEIE, which possesses similar surface energy to the organic materials and can form homogeneous film, is expected to collaborate with the adjoining organic layers, without significantly interrupting their morphology, especially for those containing low molecular weight components such as phosphorescent emitters. We envisage that this valuable tribute enables the use of small molecule light emitting materials for device fabrication and is particularly beneficial for the effective introduction of phosphorescent emitters into the emission layer of organic-inorganic light emitting devices. Phosphorescent hybrid organic-inorganic light emitting devices with solution-processed 4,4',4''-tris(carbazol-9-yl)triphenyl-amine (TCTA): 1,3-bis[(4-tert-butylphenyl)-1,3,4-oxadiazolyl]phenylene (OXD-7): Ir-complex emission layer show the maximum luminance efficiency of 64 cd/A and external quantum efficiency of 19.1%, which represent the best efficiency for organic-inorganic light emitting devices reported so far and are approximately 4 times higher than those of the analoguous devices using Cs 2 CO 3 electron injection layer. The luminance efficiency of the devices is rather independent of Ir-complex concentration, indicating balanced hole and electron transport in the emission layer and broad emission zone due to the use of hole-transporting TCTA and electron-transporting OXD-7 as the co-hosts, together with the confinement of the emission zone inside the emission layer and homogeneous dispersion of Ir-compex into the TCTA: OXD-7 host. Furthermore, the efficiency roll-off at high luminance is rather small, for example, the luminance efficiency at 10000 cd/m 2 is 62 cd/A, maintaining 97% of the maximum luminance efficiency. Our findings enrich the organic materials for the preparation of organic-inorganic light emitting devices and pave the way for the future improvement of device efficiency and stability.
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- 2015
6. The growth suppression effects of UV-C irradiation on Microcystis aeruginosa and Chlorella vulgaris under solo-culture and co-culture conditions in reclaimed water
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Hai-Sha Jiang, Hong-Ying Hu, Yuan-Mei Xue, Ji Zhou, Shang Li, Wen-Wen Yu, Xiao-Lei Yong, Yi Tao, and Guo-Hua Dao
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Growth suppression ,Microcystis ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,biology ,Ultraviolet Rays ,Chemistry ,Harmful Algal Bloom ,Chlorella vulgaris ,010501 environmental sciences ,biology.organism_classification ,01 natural sciences ,Pollution ,Algal bloom ,Coculture Techniques ,Reclaimed water ,Algae ,Environmental Chemistry ,Microcystis aeruginosa ,Irradiation ,Food science ,Waste Management and Disposal ,Incubation ,0105 earth and related environmental sciences - Abstract
Harmful algal blooms (HABs) are serious problems in landscape waters sourced from reclaimed water. In this study, the suppression effects of UV-C irradiation on microalgal growth were researched to find a possible preventive approach. Microcystis aeruginosa and Chlorella vulgaris were exposed to UV-C irradiation and then cultured in real reclaimed water for 7–18 d. UV-C irradiation at 50–200 mJ cm−2 could inhibit the growth of M. aeruginosa, C. vulgaris, and both microalgae in co-culture for 3–14, 1–3, and 1–5 d respectively. In addition, UV-C irradiation could cause damage to the cell integrity. At 100–200 mJ cm−2 UV-C, the proportion of microalgal membrane damage (Pmd) in M. aeruginosa cells increased rapidly to 56%–76% from day 3, whereas that in C. vulgaris cells increased to 23%–62% within 3 d. The photochemical efficiency (represented by Y value) of the irradiated groups was negatively affected immediately after UV-C irradiation and recovered gradually during the incubation. The Y value of M. aeruginosa cells began to recover from days 3 to 14, whereas that of C. vulgaris recovered much more quickly, from days 0.1 to 1. Overall, the irradiation-induced suppressive effects on algal growth correlated positively with the UV-C doses. Because M. aeruginosa was more sensitive to UV-C irradiation, UV-C irradiation not only controlled the total biomass of the mixed algae but also selectively reestablished the dominance of the nontoxic C. vulgaris.
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- 2020
7. Oleandrin sensitizes human osteosarcoma cells to cisplatin by preventing degradation of the copper transporter 1
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Xiaoguang Liu, Chen Liang, Guanping He, Zhongjun Liu, Zhigang Zhao, Yunlong Ma, Xiaoyu Pan, Lei Yong, Chenlong Yang, and Bao Hai
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Oleandrin ,Antineoplastic Agents ,Bone Neoplasms ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Downregulation and upregulation ,Cell Line, Tumor ,MG132 ,medicine ,Humans ,Cation Transport Proteins ,Copper Transporter 1 ,Pharmacology ,Cisplatin ,0303 health sciences ,Gene knockdown ,Osteosarcoma ,030302 biochemistry & molecular biology ,medicine.disease ,Cardenolides ,Proteasome ,chemistry ,030220 oncology & carcinogenesis ,Proteasome inhibitor ,Cancer research ,medicine.drug - Abstract
A major problem in osteosarcoma treatment is cisplatin resistance. We have reported the anti-osteosarcoma effect of oleandrin; however, whether oleandrin sensitizes osteosarcoma to cisplatin is unknown. We investigated the chemosensitization of oleandrin and potential mechanisms in osteosarcoma cells U-2OS, SaOS-2, and MG-63. The median-effect analysis demonstrated that cisplatin + oleandrin exerted synergistic (U-2OS and MG-63) or additive effects (SaOS-2), which were consistent with the changes of the intracellular accumulation of platinum (Pt) and Pt-DNA adducts. Immunohistochemistry staining showed that the expression level of the mature form CTR1, the major influx transporter of cisplatin, was low in osteosarcoma tissue. However, oleandrin with or without cisplatin significantly increased the expression and membrane localization of the mature CTR1. Furthermore, CTR1 knockdown reversed the synergistic effect and decreased cisplatin uptake. The mRNA microarray analysis suggested that oleandrin downregulated the expression of proteasome-related genes, which was verified by the proteasome activity assay. Besides, the proteasome inhibitor MG132 upregulated the expression of the mature CTR1 in U-2OS and MG-63 cells. Overall, we conclude that oleandrin sensitizes osteosarcoma cells to cisplatin in synergistic or additive manners. The synergy results from the enhanced cisplatin uptake via oleandrin-mediated inhibition of proteasome activity and subsequent blockage of the mature CTR1 degradation.
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- 2018
8. Donor–acceptor Stenhouse adduct-grafted polycarbonate surfaces: selectivity of the reaction for secondary amine on surface
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Singh, Sukhdeep, Mai, Patrick, Borowiec, Justyna, Zhang, Yixin, Lei, Yong, and Schober, Andreas
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Chemistry ,polycarbonate ,donor–acceptor Stenhouse adducts ,amine indicator ,lcsh:Q ,lcsh:Science ,secondary amine ,Research Article - Abstract
Donor–acceptor Stenhouse adducts (DASAs) are gaining attention from organic and material chemists due to their visible light-stimulated photochromic properties. In this report, we present a facile method for grafting coloured triene on polycarbonate surface, without involving any pre-treatments like plasma activation, etc. The chemoselectivity of carbonate with a primary amine and Meldrum's activated furan (MAF) with polymer bound secondary amine has been exploited to graft photoswitchable DASA on the polymer surface. Primary, secondary and tertiary amine-functionalized polycarbonate surfaces have been prepared to evaluate the reactivity of amine with MAF.
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- 2018
9. Y-box binding protein-1 promotes tumorigenesis and progression via the epidermal growth factor receptor/AKT pathway in spinal chordoma
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Chen Liang, Zhongjun Liu, Yunlong Ma, Lei Yong, Chenlong Yang, Bin Zhu, Hua Zhou, Peng Wang, Xiaoguang Liu, and Xiao Liu
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0301 basic medicine ,Male ,Cancer Research ,Carcinogenesis ,Mice, SCID ,medicine.disease_cause ,YBX1 ,0302 clinical medicine ,Mice, Inbred NOD ,Epidermal growth factor receptor ,Spinal Chordoma ,Child ,Mice, Knockout ,biology ,Chemistry ,General Medicine ,Middle Aged ,ErbB Receptors ,Oncology ,030220 oncology & carcinogenesis ,Disease Progression ,Female ,RNA Interference ,Original Article ,Signal Transduction ,musculoskeletal diseases ,Adult ,Adolescent ,EGFR ,03 medical and health sciences ,Young Adult ,Cell Line, Tumor ,medicine ,Chordoma ,Animals ,Humans ,Protein kinase B ,PI3K/AKT/mTOR pathway ,Aged ,Spinal Neoplasms ,Cell growth ,AKT ,Original Articles ,Y box binding protein 1 ,medicine.disease ,Xenograft Model Antitumor Assays ,tumorigenesis ,030104 developmental biology ,RNAi Therapeutics ,Cancer research ,biology.protein ,Y-Box-Binding Protein 1 ,Proto-Oncogene Proteins c-akt - Abstract
Chordomas are rare bone tumors with a poor prognosis and no approved targeted therapy. Y-box binding protein-1 (YBX1) promotes tumor growth, invasion and drug resistance. However, the role of YBX1 in chordoma is unclear. In this study, we examined the expression of YBX1 using immunohistochemistry and found that YBX1 was significantly upregulated in 32 chordoma tissues compared to distant normal tissues. In addition, YBX1 upregulation was associated with surrounding tissue invasion, recurrence and poor prognosis. Biological function studies demonstrated that YBX1 promoted cell proliferation and invasion, accelerated G1/S phase transition, and inhibited apoptosis. Further investigation revealed that YBX1 enhanced epidermal growth factor receptor (EGFR) transcription by directly binding to its promoter in chordoma cells. YBX1 regulated protein expression of p-EGFR, p-AKT and its downstream target genes that influenced cell apoptosis, cell cycle transition and cell invasion. YBX1 activated the EGFR/AKT pathway in chordoma and YBX1-induced elevated expression of key molecules in the EGFR/AKT pathway were downregulated by EGFR and AKT pathway inhibitors. These in vitro results were further confirmed by in vivo data. These data showed that YBX1 promoted tumorigenesis and progression in spinal chordoma via the EGFR/AKT pathway. YBX1 might serve as a prognostic and predictive biomarker, as well as a rational therapeutic target, for chordoma.
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- 2018
10. Oleandrin synergizes with cisplatin in human osteosarcoma cells by enhancing cell apoptosis through activation of the p38 MAPK signaling pathway
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Zhongjun Liu, Zhigang Zhao, Peng Wang, Xiao Liu, Bin Zhu, Chen Liang, Yunlong Ma, Xiaoguang Liu, Lei Yong, and Guanping He
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0301 basic medicine ,P38 MAPK ,Cancer Research ,Oleandrin ,Programmed cell death ,MAP Kinase Signaling System ,Antineoplastic Agents ,Apoptosis ,Toxicology ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Cell Line, Tumor ,medicine ,Humans ,Pharmacology (medical) ,DAPI ,Viability assay ,Pharmacology ,Cisplatin ,Osteosarcoma ,Cell growth ,Drug Synergism ,medicine.disease ,Cardenolides ,030104 developmental biology ,Oncology ,chemistry ,030220 oncology & carcinogenesis ,Cancer research ,Synergistic effect ,Original Article ,medicine.drug ,Signal Transduction - Abstract
Purpose Our previous studies have reported the antitumor effect of oleandrin on osteosarcoma; however, its chemosensitizing effect in osteosarcoma treatment is still unknown. Therefore, we explored the sensitizing effects of oleandrin to cisplatin in osteosarcoma and investigated the potential mechanisms. Methods After exposure to oleandrin and/or cisplatin, CCK-8 and colony formation assays, DAPI staining and flow cytometry were performed to detect cell proliferation and apoptosis in 143B, U-2OS and MG-63 osteosarcoma cells. The median-effect analysis was applied to evaluate the combined effect. Western blot was used to determine the expression of related proteins. Osteosarcoma xenografts and histological observations were applied to confirm the combined effect in vivo. Results Compared with cisplatin or oleandrin alone, the combined treatment significantly inhibited cell proliferation and induced cell apoptosis. The median-effect analysis indicated a synergistic cytotoxic effect. The combined treatment downregulated Bcl-2 and upregulated Bax and cleaved caspase-3, -8 and -9. And the suppression of caspases reduced cell death. Furthermore, oleandrin alone or with cisplatin, activated the p38 MAPK/Elk-1 pathway. The inhibition of the p38 MAPK pathway increased cell viability and reduced apoptosis. In vivo, the combined treatment was also verified to significantly inhibit tumor growth, induce apoptosis and activate the p38 MAPK pathway. Conclusions The combination of oleandrin with cisplatin exerts a synergistic antitumor effect in osteosarcoma, which relates to the activation of the p38 MAPK pathway.
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- 2018
11. Cross Talk Between Autophagy and Apoptosis Contributes to ZnO Nanoparticle-Induced Human Osteosarcoma Cell Death
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Lei Yong, Zhigang Zhao, Zhongjun Liu, Xiaoyu Pan, Peng Wang, Xiao Liu, Guanping He, Bao Hai, Chuanbin Mao, Yunlong Ma, Chenlong Yang, Xiaoguang Liu, Chen Liang, and Ye Zhu
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0301 basic medicine ,Programmed cell death ,Cell Survival ,Blotting, Western ,Biomedical Engineering ,Pharmaceutical Science ,Metal Nanoparticles ,Apoptosis ,02 engineering and technology ,Mitochondrion ,Article ,Biomaterials ,03 medical and health sciences ,Microscopy, Electron, Transmission ,Cell Line, Tumor ,Extracellular ,Autophagy ,Humans ,Viability assay ,Cell Proliferation ,chemistry.chemical_classification ,Reactive oxygen species ,Osteosarcoma ,Cell growth ,Caspase 3 ,021001 nanoscience & nanotechnology ,Cell biology ,Oxidative Stress ,030104 developmental biology ,chemistry ,Microscopy, Fluorescence ,Zinc Oxide ,0210 nano-technology ,Reactive Oxygen Species - Abstract
Killing osteosarcoma cells by zinc oxide nanoparticles (ZnO NPs) and its underlying sub-cellular mechanism have never been studied. Here we find that the NPs induced crosstalk between apoptosis and autophagy, which lead to osteosarcoma cell death. Specifically, the NP uptake promotes autophagy by inducing accumulation of autophagosomes along with impairment of lysosomal functions. The autophagy further causes the uptaken NPs to release zinc ions by promoting their dissolution. These intracellular zinc ions, together with those that are originally released from the extracellular NPs and flowed into the cells, collectively target and damage mitochondria to produce reactive oxygen species (ROS). Then the ROS inhibit cell proliferation by arresting S phase and trigger apoptosis by extrinsic and intrinsic pathways, ultimately leading to cell death. More importantly, suppression of the early stage autophagy restores cell viability by abolishing apoptosis whereas blockade of the late stage autophagy inversely enhances apoptosis. In contrast, inhibition of apoptosis shows a limited ability to restore cell viability but obviously enhance autophagy. Notably, cell viability is strongly ameliorated by the combination of inhibitors for both the late stage autophagy and the apoptosis. These findings provide a mechanistic understanding of the NP-directed autophagy and apoptosis in osteosarcoma cells.
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- 2018
12. STUDY ON EXTRACTION OF FLAVONOIDS FROM FRUIT OF ROSA DAVURICA P ALL BY DIFFERENT METHODS AND ITS ANTIOXIDANT ACTIVITY
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Wang Xiaolin, Zhang Lin, Di Song, Zhong Fangli, and Lei Yong-ping
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Antioxidant ,Traditional medicine ,Chemistry ,medicine.medical_treatment ,Extraction (chemistry) ,medicine ,Rosa davurica - Published
- 2018
13. STUDY ON THE EXTRACTION OF PIGMENT FROM FRUIT OF ROSA DAVURICA PALL.WITH MICROWAVE COENZYME METHOD AND ITS STABILITY AND INOXIDIZABILITY
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Yin Jia-mian, Zhong Fangli, Wang Xiaolin, Lei Yong-ping, and Di Song
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Pigment ,Chromatography ,biology ,Chemistry ,visual_art ,Extraction (chemistry) ,visual_art.visual_art_medium ,biology.protein ,Rosa davurica ,Microwave ,Cofactor - Published
- 2018
14. Hollow ternary PtPdCu nanoparticles: a superior and durable cathodic electrocatalyst† †Electronic supplementary information (ESI) available: Experimental details, XRD patterns, ICP data, EDS data, TEM and HADDF-STEM images, EDX line-scan profile and cyclic voltammetry (CV). See DOI: 10.1039/c4sc04037f Click here for additional data file
- Author
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Liu, Xiao-Jing, Cui, Chun-Hua, Li, Hui-Hui, Lei, Yong, Zhuang, Tao-Tao, Sun, Meng, Arshad, Muhammad Nadeem, Albar, Hassan A., Sobahi, Tariq R., and Yu, Shu-Hong
- Subjects
Chemistry - Abstract
Hollow PtPdCu nanoparticles with a Pt-enriched surface, formed by the dealloying action of acetic acid, exhibit superior durability and catalytic activity toward the ORR., Hollow alloyed nanoparticles (NPs) represent one kind of promising fuel cell electrocatalyst. However, the formation of single-cavity hollow structures by a dealloying process is quite challenging owing to the random leaching/dissolution of transition metals, surface passivation and the limited diffusion distance of the noble metals. Here we present a facile method to prepare hollow PtPdCu NPs derived from monodisperse alloy NPs by an acetic acid-assisted dealloying process. Here, acetic acid not only acts as a chemical etching agent but also plays an important role in the removal of the residual surfactants for colloidal NPs. Our findings rectify the current knowledge that hollow alloyed NPs cannot be prepared by a dealloying strategy and provide further understanding of the dealloying process in a ternary system. Such unique hollow ternary PtPdCu NPs exhibit outstanding durability and improved catalytic activity toward the oxygen reduction reaction.
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- 2015
15. The Apoptosis Induction of Oleandrin on Osteosarcoma Cells through Regulating Mitochondrial- and Death Receptor-Dependent Apoptotic Pathways in Vitro
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Chunyu Song, Zhongjun Liu, Lei Yong, Huilei Yu, Bin Zhu, Xiaoguang Liu, Yunlong Ma, Peng Wang, and Xiao Liu
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Oleandrin ,biology ,Chemistry ,Intrinsic apoptosis ,Apoptosis induction ,medicine.disease ,In vitro ,chemistry.chemical_compound ,Apoptosis ,Cancer research ,biology.protein ,medicine ,Osteosarcoma ,Receptor ,Caspase ,oncology_oncogenics - Abstract
Our previous study has found the anti-tumor activity of oleandrin in osteosarcoma cells in vitro, but the signal transduction process of cell apoptosis induced by oleandrin is uncertain, which is explored in this study. Fluorescence staining and flow cytometry (FCM) was performed to detect the cell apoptosis, intracellular reactive oxygen species (ROS) and mitochondrial membrane potential (MMP). Caspase-3 activity was detected using a commercial kit. The protein expression of cytoplasmic cytochrome c, mitochondrial cytochrome c, bcl-2, bax, caspase-9, Fas, FasL, caspase-8 and caspase-3 was detected using western blot. A pan-caspase inhibitor, z-VAD-fmk, was applied to block the apoptotic pathway and the apoptosis status were re-tested. We found that oleandrin significantly induced the increased apoptosis of U2OS cells. Meanwhile, the intracellular ROS was elevated, but the MMP decreased. The cytochrome c in mitochondria was notably decreased but increased in cytoplasm. The caspase-3 activity was also enhanced with the increase of drug concentration and treatment time. Oleandrin also down-regulated the level of bcl-2, but remarkably up-regulated the expression of bax, cleaved caspase-9, Fas, FasL, cleaved caspase-8 and cleaved caspase-3. Furthermore, the pre-treatment with z-VAD-fmk almost completely reverted the oleandrin-induced apoptosis. The results suggested that oleandrin induces the apoptosis of osteosarcoma cells via mitochondrial- and death receptor-dependent pathways.
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- 2016
16. Regulation of Intrinsic and Extrinsic Apoptotic Pathways in Osteosarcoma Cells Following Oleandrin Treatment
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Bin Zhu, Chunyu Song, Yunlong Ma, Huilei Yu, Zhongjun Liu, Lei Yong, Peng Wang, Xiao Liu, and Xiaoguang Liu
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oleandrin ,osteosarcoma ,apoptosis ,caspases ,0301 basic medicine ,Oleandrin ,Apoptosis ,Fas ligand ,Amino Acid Chloromethyl Ketones ,lcsh:Chemistry ,chemistry.chemical_compound ,0302 clinical medicine ,lcsh:QH301-705.5 ,Spectroscopy ,bcl-2-Associated X Protein ,Membrane Potential, Mitochondrial ,Caspase 8 ,Caspase 3 ,Cytochrome c ,Cytochromes c ,General Medicine ,Caspase 9 ,Computer Science Applications ,Cell biology ,Mitochondria ,Gene Expression Regulation, Neoplastic ,Cardenolides ,Proto-Oncogene Proteins c-bcl-2 ,030220 oncology & carcinogenesis ,Oligopeptides ,Signal Transduction ,Fas Ligand Protein ,Biology ,Catalysis ,Article ,Inorganic Chemistry ,Cardiac Glycosides ,03 medical and health sciences ,Bcl-2-associated X protein ,Cell Line, Tumor ,Humans ,Physical and Theoretical Chemistry ,Molecular Biology ,Osteoblasts ,Organic Chemistry ,Intrinsic apoptosis ,Antibodies, Neutralizing ,Antineoplastic Agents, Phytogenic ,030104 developmental biology ,lcsh:Biology (General) ,lcsh:QD1-999 ,chemistry ,biology.protein ,Reactive Oxygen Species - Abstract
Our previous study has reported the anti-tumor effect of oleandrin on osteosarcoma (OS) cells. In the current study, we mainly explored its potential regulation on intrinsic and extrinsic apoptotic pathway in OS cells. Cells apoptosis, reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) were detected using fluorescence staining and flow cytometry. Caspase-3 activity was detected using a commercial kit. The levels of cytoplasmic cytochrome c, mitochondrial cytochrome c, bcl-2, bax, caspase-9, Fas, FasL, caspase-8 and caspase-3 were detected by Western blotting. z-VAD-fmk was applied to block both intrinsic and extrinsic apoptosis pathways, and cells apoptosis was also tested. Furthermore, we used z-LEHD-fmk and Fas blocking antibody to inhibit intrinsic and extrinsic pathways, separately, and the selectivity of oleandrin on these pathways was explored. Results showed that oleandrin induced the apoptosis of OS cells, which was accompanied by an increase in ROS and a decrease in MMP. Furthermore, cytochrome c level was reduced in mitochondria but elevated in the cytoplasm. Caspase-3 activity was enhanced by oleandrin in a concentration- and time-dependent manner. Oleandrin also down-regulated the expression of bcl-2, but up-regulated bax, caspase-9, Fas, FasL, caspase-8 and caspase-3. In addition, the suppression of both apoptotic pathways by z-VAD-fmk greatly reverted the oleandrin-induced apoptosis. Moreover, the suppression of one pathway by a corresponding inhibitor did not affect the regulation of oleandrin on another pathway. Taken together, we concluded that oleandrin induced apoptosis of OS cells via activating both intrinsic and extrinsic apoptotic pathways.
- Published
- 2016
17. Copper trihydroxychlorides as pigments in China
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Lei Yong
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geography ,Painting ,geography.geographical_feature_category ,media_common.quotation_subject ,chemistry.chemical_element ,Conservation ,Art ,engineering.material ,Ancient history ,Archaeology ,Copper ,Five Dynasties ,Pigment ,Cave ,chemistry ,visual_art ,engineering ,visual_art.visual_art_medium ,Bronze ,China ,Historical record ,media_common - Abstract
Based on recent pigment analyses of many dated caves and murals, as well as investigation of historical records and inscriptions in China, it is proposed that the most popular green pigment for wall painting and architecture might be copper trihydroxychlorides from North Dynasty (386–581 CE) until late Qing Dynasty (1840–1911 CE), rather than malachite. Furthermore, the synthetic technology of making bronze corrosion artificially probably began to dominate the green pigment supply in Five Dynasties (907–960 CE) or Song Dynasty (960–1279 CE).
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- 2012
18. Inhibition of oleandrin on the proliferation and invasion of osteosarcoma cells in vitro by suppressing Wnt/β-catenin signaling pathway
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Jia Shao, Huilei Yu, Yunlong Ma, Xiao Liu, Zhongjun Liu, Bin Zhu, Lei Yong, and Xiaoguang Liu
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Cancer Research ,Oleandrin ,Beta-catenin ,Proliferation ,Antineoplastic Agents ,Apoptosis ,Bone Neoplasms ,Biology ,chemistry.chemical_compound ,Invasion ,Western blot ,Cell Line, Tumor ,medicine ,Humans ,Neoplasm Invasiveness ,RNA, Messenger ,Wnt Signaling Pathway ,beta Catenin ,Cell Proliferation ,Osteosarcoma ,medicine.diagnostic_test ,Reverse Transcriptase Polymerase Chain Reaction ,Cell growth ,Research ,Wnt signaling pathway ,Gene Expression Regulation, Neoplastic ,Wnt Proteins ,Cardenolides ,Matrix Metalloproteinase 9 ,Oncology ,chemistry ,Cell culture ,Immunology ,biology.protein ,Cancer research ,Matrix Metalloproteinase 2 ,Signal transduction ,Antitumor activity ,Wnt/β-catenin signaling - Abstract
Background Osteosarcoma (OS) is a high-grade bone sarcoma with early metastasis potential, and the clinical chemotherapy drugs that are currently used for its treatment have some limitations. Recently, several studies have reported the selective antitumor effect of oleandrin on various tumor cells. In this study, we aimed to evaluate the effects and underlying mechanisms of oleandrin on OS cells. Methods The effect of oleandrin on the proliferation, morphology, and apoptosis of U2OS and SaOS-2 cells were analyzed in vitro. The activity of the Wnt/β-catenin signaling pathway was determined using a dual luciferase assay. Semi-quantitative RT-PCR and western blot assays were performed to evaluate the mRNA and total protein expression of the downstream target genes. Changes of β-catenin in intracellular localization were also explored using a western blot after separating the nucleus and cytoplasm proteins. The MMP-2 and MMP-9 enzymatic activities were determined using gelatin zymography. Results Oleandrin significantly inhibited the proliferation and invasion of OS cells in vitro, and induced their apoptosis. After treatment with oleandrin, the TOP/FOP flash ratio in OS cells was noticeably decreased, which indicated that the Wnt/β-catenin signaling pathway was repressed. The expression of related Wnt target genes and total β-catenin was downregulated, and a reduced nuclear β-catenin level by oleandrin was observed as well. In addition, oleandrin suppressed the activities of MMP-2 and MMP-9. Conclusions Oleandrin, in vitro, exerted a strong antitumor effect on human OS cells by suppressing the Wnt/β-catenin signaling pathway, which interfered with the proliferation and invasion of OS cells, as well as induced cells apoptosis. Moreover, the expression and activities of MMP-2 and MMP-9 were downregulated by oleandrin, which contributed to the cells’ lower invasiveness.
- Published
- 2015
19. Frequencies of ahFAD2A Alleles in Chinese Peanut Mini Core Collec-tion and Its Correlation with Oleic Acid Content
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Lei Yong, Wen Qigen, Jiang Huifang, Huang Jiaquan, Yan LiYing, and Liao Bo-shou
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Oleic acid ,chemistry.chemical_compound ,chemistry ,Plant composition ,Correlation analysis ,Botany ,Plant Science ,Food science ,Biology ,Allele ,Agronomy and Crop Science ,Biotechnology - Published
- 2010
20. Preparation and Photoactivity of Titanium Dioxide-Coated Carbon Felt Using Supercritical Carbon Dioxide
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You Ji Li, Wei Chen, Lei Yong Li, and Ming Yuan Ma
- Subjects
Supercritical carbon dioxide ,Materials science ,Scanning electron microscope ,Inorganic chemistry ,General Engineering ,chemistry.chemical_element ,Supercritical fluid ,Congo red ,chemistry.chemical_compound ,chemistry ,Titanium dioxide ,Photocatalysis ,Carbon ,Nuclear chemistry ,BET theory - Abstract
TiO2–coated carbon felt (TCF) was prepared via a supercritical treatment with titanium tetraisopropoxide (TTIP) and different carbon felt as a precursor and support, respectively. The TCF samples with different carbon felts were characterized by X-ray diffraction, scanning electron microscopy, UV-VIS spectroscopy, particle size analyzer and BET surface area. The photocatalytic activities of samples were evaluated by congo red (CR) degradation. The result reveals that all the three samples show much higher photoactivity than the commercial P25. The activity order of the three samples is TCF1< TCF2 < TCF3. The photoactivity is strongly dependent on the surface area and the crystallite size: the larger the surface area and the smaller the crystallites, the higher the efficacy of photocatalytic degradation. The optimal photocatalytic condition is a CR concentration of 45 mg/l at pH 7.
- Published
- 2010
21. Photocatalytic Degradation of Methylene Blue Using Immobilized Nanoparticles of TiO2 Supported by SBA-15 Surface
- Author
-
Ming Yuan Ma, You Ji Li, Wei Chen, and Lei Yong Li
- Subjects
Nanocomposite ,Materials science ,General Engineering ,Nanoparticle ,Supercritical fluid ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Photocatalysis ,Degradation (geology) ,Composite material ,Photocatalytic degradation ,Spectroscopy ,Methylene blue - Abstract
TiO2-SBA-15 surface (TSS) composites were prepared by the supercritical pretreatment and then sol-gel process with using paraffin used as a clogging agent. The as-grown materials were characterized by using X-ray diffraction, UV-VIS spectroscopy and nitrogen absorption. The photocatalytic activities of TSS were evaluated by quantifying the degradation of methylene blue solution under UV light. Compared with TiO2-SBA-15 (TS) composites prepared only by the sol–gel method, TSS composites remain in mesostructure with high surface areas due to clogging effect of paraffin on SBA-15 cavity. Additionally, the small crystalline size of TiO2 in TSS is attributed to the fact that silica support baffles the agglomeration ofTiO2 nanoparticles. In comparison of TS composites and pure TiO2, higher photocatalytic activity of TSS is obtained and mainly attributed to larger surface areas and greater band-gap energy.
- Published
- 2010
22. Novel High Oil Germplasm with Resistance to Aspergillus flavus and Bacterial Wilt Developed from Recombinant Inbred Lines
- Author
-
Ren Xiaoping, Wang Shengyu, Liao Bo-shou, Huang Jiaquan, Jiang Huifang, Lei Yong, Yan LiYing, and Li Dong
- Subjects
Germplasm ,Aflatoxin ,biology ,Bacterial wilt ,Aspergillus flavus ,Plant Science ,Plant disease resistance ,biology.organism_classification ,Microbiology ,law.invention ,chemistry.chemical_compound ,chemistry ,Inbred strain ,law ,Botany ,Recombinant DNA ,Mycotoxin ,Agronomy and Crop Science ,Biotechnology - Published
- 2010
23. Optical Hydrogen Sulfide Gas Sensor Based on the Fluorescence Quenching of ZnCeS
- Author
-
肖虎 Xiao Hu, 雷勇 Lei Yong, 杨晓占 Yang Xiao-zhan, and 冯文林 Feng Wenlin
- Subjects
chemistry.chemical_compound ,Materials science ,chemistry ,Hydrogen sulfide ,Photochemistry ,Atomic and Molecular Physics, and Optics - Published
- 2018
24. Effect of Alkyl Substitution on the Electronic Structure and Spectrum of Rhodamine
- Author
-
Huo Ji-Chuan and Lei Yong-Lin
- Subjects
Rhodamine ,Crystallography ,chemistry.chemical_compound ,Materials science ,chemistry ,Alkyl substitution ,Electronic structure ,Physical and Theoretical Chemistry ,Spectrum (topology) - Published
- 2010
25. Preparation of Cost-Effective TiO2-Outerloaded Porous Lava Composites using Supercritical CO2 and Their Photocatalytic Activity for Methylene Blue Degradation
- Author
-
Lei-yong Li, You-ji Li, Minyuan Ma, and Wei Chen
- Subjects
Supercritical carbon dioxide ,Materials science ,organic chemicals ,General Medicine ,Supercritical fluid ,Catalysis ,chemistry.chemical_compound ,Adsorption ,chemistry ,Photocatalysis ,bacteria ,Degradation (geology) ,Composite material ,Methylene blue ,Sol-gel - Abstract
Cost-effective TiO2-outerloaded lava composites (TOLs) were prepared using supercritical CO2 and sealing lava as well as tetrabutyl titanate as a support and a precursor, respectively. The important factors affecting methylene blue (MB) oxidation efficiency were investigated including the initial concentration of MB, the pH, and catalyst concentration. The results show that TOLs have a higher degradation efficiency than pure TiO2 and TiO2-loaded lava composites (TLLs) because of the high adsorption capacity of MB and the small crystalline size of the TiO2 particles in addition to a synergetic effect for adsorption and photocatalytic degradation. The optimum conditions were a MB concentration of 1.5 mg/L at pH 8 with a TOLs concentration of 6.8 mg/L for the fastest MB degradation. Additionally, the used TOLs retained high activity for MB photocatalytic degradation.
- Published
- 2010
26. Genetic Variation of Fatty Acid Components in Arachis Species and Development of Interspecific Hybrids with High Oleic and Low Palmitic Acids
- Author
-
Liao Bo-shou, Huang Jiaquan, Jiang Huifang, Lei Yong, and Ren Xiaoping
- Subjects
chemistry.chemical_classification ,Arachis ,biology ,Linoleic acid ,Fatty acid ,Plant Science ,biology.organism_classification ,Palmitic acid ,Oleic acid ,chemistry.chemical_compound ,chemistry ,Botany ,Genetic variation ,Stearic acid ,Agronomy and Crop Science ,Biotechnology ,Hybrid - Published
- 2009
27. Application of Three Combustion Models to a Model Combustor
- Author
-
Ian Campbell and Lei-Yong Jiang
- Subjects
Materials science ,Diffusion flame ,Thermodynamics ,General Medicine ,Mechanics ,Combustion ,Flow field ,Physics::Fluid Dynamics ,chemistry.chemical_compound ,chemistry ,Propane ,Combustor ,Physics::Chemical Physics ,Conjugate - Abstract
The entire flow field of a propane diffusion flame combustor, including interior and exterior conjugate heat transfers, was studied numerically. The results obtained from three combustion models, t...
- Published
- 2005
28. Reynolds Analog in Combustor Modeling
- Author
-
Lei-Yong Jiang and Ian C. Campbell
- Subjects
Chemistry ,Turbulence ,Schmidt number ,Prandtl number ,Diffusion flame ,Mechanics ,Physics::Fluid Dynamics ,symbols.namesake ,Classical mechanics ,symbols ,Combustor ,Turbulent Prandtl number ,Combustion chamber ,Reynolds-averaged Navier–Stokes equations - Abstract
Accurate temperature prediction is vital for the development of advanced combustion systems. The Reynolds analogy concept has been almost exclusively used in current turbulent reacting flow RANS simulations. In this paper, this hypothesis applied to a diffusion flame model combustor is discussed and assessed. Some of the numerical results obtained from a flamelet combustion model with the turbulence Prandtl/Schmidt number from 0.25 to 0.85 are presented, and compared with a benchmark experimental database. It is found that the turbulence Prandtl/Schmidt number has significant effect on the predicted temperature and species fields inside the combustor, as well as the temperature profile at the combustor wall. In contrast, its effect on the velocity field is insignificant in the range assessed. With the optimized turbulence Prandtl/Schmidt number, both velocity and scalar fields can be reasonably and quantitatively predicted. For the present configuration and operating conditions, the optimal Prandtl/Schmidt number is 0.5, lower than the commonly accepted values, ∼0.70. This study suggests that for accurate prediction of scalar transfers in turbulent reacting flows, the Reynolds analogy concept should be improved and new approaches should be developed.
- Published
- 2007
29. A Critical Evaluation of NOx Modeling in a Model Combustor
- Author
-
Ian C. Campbell and Lei-Yong Jiang
- Subjects
Materials science ,Field (physics) ,Chemistry ,Turbulence ,Mechanical Engineering ,Diffusion flame ,Energy Engineering and Power Technology ,Aerospace Engineering ,Thermodynamics ,Mechanics ,Dissipation ,Combustion ,Fuel Technology ,Nuclear Energy and Engineering ,Thermal ,Heat transfer ,Combustor ,Combustion chamber - Abstract
Reliable NOx modeling depends on the accurate prediction of both velocity and temperature fields. The velocity and temperature fields of a propane diffusion flame combustor, with interior and exterior conjugate heat transfers, were first numerically studied. The results from three combustion models, together with the re-normalization group (RNG) k-e turbulence model and the discrete ordinates radiation model are discussed, and compared with comprehensive experimental measurements. The flow patterns and the recirculation zone length in the combustion chamber are excellently predicted, and the mean axial velocities are in fairly good agreement with the experimental data for all three combustion models. The mean temperature profiles are fairly well captured by the probability density function (PDF) and eddy dissipation (EDS) combustion models. However, the EDS-finite-rate combustion model fails to provide an acceptable temperature field. Based on the acceptable velocity and temperature fields, a number of NO modeling approaches were evaluated in a post-processing mode. The partial-equilibrium approach of O and OH radical concentrations shows a significant effect on the thermal NO formation rate. In contrast, the prompt NO, the NO re-burn mechanism and the third reaction of the extended Zeldovich mechanism have negligible effects on the overall NO formation in the present study. This study indicates that the semi-empirical, post-processing NO model can provide valuable NO simulations as long as the velocity and temperature fields are adequately predicted.Copyright © 2004 by ASME
- Published
- 2004
30. Application of Various Combustion Models to a Generic Combustor
- Author
-
Lei-Yong Jiang and Ian C. Campbell
- Subjects
Physics::Fluid Dynamics ,Chemistry ,Turbulence ,Heat transfer ,Combustor ,Thermodynamics ,Probability density function ,Mechanics ,Combustion chamber ,Dissipation ,Combustion ,NOx - Abstract
The flow-field of a generic gas combustor with interior and exterior conjugate heat transfers was numerically studied. Results obtained from three combustion models, combined with the re-normalization group (RNG) k-e turbulence model, discrete ordinates radiation model, and partial equilibrium NOx model are presented and discussed. The numerical results are compared with a comprehensive database obtained from a series of experimental tests. The flow patterns and the recirculation zone length are excellently predicted, and the mean axial velocities are in fairly good agreement with the experimental measurements, particularly at downstream sections for all three combustion models. The mean temperature profiles are also fairly well captured by the probability density function (PDF) and eddy dissipation (EDS) combustion models. The EDS-finite-rate combustion model fails to provide acceptable temperature field. In general, the PDF shows some superiority over the EDS and EDS-finite-rate models. NOx levels predicted by the EDS model are in reasonable agreement with the experimental measurements.Copyright © 2003 by ASME
- Published
- 2003
31. Study of Mixing Enhancement From a 12-Lobe Convoluted Mixer
- Author
-
Ibrahim Yimer, Shaji Manipurath, Lei-Yong Jiang, and Ian C. Campbell
- Subjects
Physics::Fluid Dynamics ,Chemistry ,Planar laser-induced fluorescence ,Combustor ,Mechanical engineering ,Mechanics ,Combustion chamber ,Reynolds-averaged Navier–Stokes equations ,Jet noise ,Turbine ,Mixing (physics) ,Propulsive efficiency - Abstract
Lobed mixers have been used in a variety of engineering applications, such as jet noise reduction, infrared suppression and improvement of propulsive efficiency for turbine engines. More recently, they have emerged as an attractive method to enhance mixing between fuel and air in advanced low-emission gas turbine combustors. The objectives of the present work were to assess the effectiveness of these devices for use inside the combustor and provide experimental data to validate CFD predictions. The mixing enhancements due to streamwise vortices generated from a 12-lobe convoluted mixer were characterized using Planar Laser Induced Fluorescence (PLIF) measurements, while 2-D PIV measurements established the underlying velocity field. The geometrical set-up of the mixing system is pertinent to many combustion systems using advanced lean premixed concepts with gaseous fuels. In addition to the benchmark case with no mixer, two different lobe geometries were considered, a semi-circle (or round) lobe and a square lobe. In this paper the experimental results are presented and discussed. Numerical predictions were performed for the semi-circle lobe geometry using a Reynolds-averaged Navier-Stokes (RANS) code and the results are compared with experimental measurements.
- Published
- 2003
32. Field plate engineering for GaN-based Schottky barrier diodes
- Author
-
Zhang Rong, Lu Hai, Zheng Youdou, Shi Hongbiao, Chen Dun-Jun, and Lei Yong
- Subjects
Permittivity ,Materials science ,business.industry ,Schottky barrier ,Schottky diode ,Gallium nitride ,Semiconductor device ,Dielectric ,Condensed Matter Physics ,Electronic, Optical and Magnetic Materials ,chemistry.chemical_compound ,chemistry ,Materials Chemistry ,Optoelectronics ,Electrical and Electronic Engineering ,business ,Critical field ,Diode - Abstract
The practical design of GaN-based Schottky barrier diodes (SBDs) incorporating a field plate (FP) structure necessitates an understanding of their working mechanism and optimization criteria. In this work, the influences of the parameters of FPs upon breakdown of the diode are investigated in detail and the design rules of FP structures for GaN-based SBDs are presented for a wide scale of material and device parameters. By comparing three representative dielectric materials (SiO2, Si3N4 and Al2O3) selected for fabricating FPs, it is found that the product of dielectric permittivity and critical field strength of a dielectric material could be used as an index to predict its potential performance for FP applications.
- Published
- 2013
33. Preparation and Electrochemical Properties of Polyaniline/Carbon Nanofiber Composite Materials
- Author
-
Lei Yong Zhang, Shui Liang Chen, Qiao Hui Guo, Shui Jian He, and Hao Qing Hou
- Subjects
Supercapacitor ,Thermogravimetric analysis ,Materials science ,Carbon nanofiber ,Carbon nanotube ,law.invention ,chemistry.chemical_compound ,chemistry ,law ,Specific surface area ,Polyaniline ,Physical and Theoretical Chemistry ,Composite material ,Cyclic voltammetry ,In situ polymerization - Abstract
Polyaniline/carbon nanofiber (PANI/CNF) composite materials were prepared by in situ polymerization. The functional group, composition, surface morphology, and specific surface area of composite materials were characterized by Fourier transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and Brunauer-Emmelt-Teller analysis. Cyclic voltammetry (CV) and galvanotactic charge-discharge methods were used to study the electrochemical properties of the PANI/CNF composite materials. Results showed that the composite materials had a rough surface with a burry PANI structure that was uniformly distributed over the CNF. The composite materials, as electrodes, showed good reversibility in redox reactions. The specific capacitance of 44.4%(w) PANI/CNF was 587.1 F.g(-1), the specific energy was 66.1 Wh.kg(-1) at a current density of 100 mA.g(-1), and the specific power was 1014.2 W.kg(-1) at a current density of 800 mA.g(-1). Moreover, the specific capacitance of PANI/CNF only decreased by 28% after 1000 charge-discharge cycles. Therefore, the PANI/CNF composite material is an excellent material for use in supercapacitors because of its high electrical conductivity and large specific capacitance.
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