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A dual timescale model for micro-mixing and its application in LES-TPDF simulations of turbulent nonpremixed flames

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Chinese Journal of Aeronautics 2019年第4期32卷 875-887页

作者： Fang WANG Rui LIU Li DOU Denghuan LIU Jie JIN Aero-Engine Numerical Simulation Research Center School of Energy and Power EngineeringBeihang University Collaborative Innovation Center for Advanced Aero-Engine

The numerical simulation of modern aero-engine combustion chamber needs accurate description of the interaction between turbulence and chemical reaction mechanism. The Large Eddy Simulation(LES) method with the Transported Probability Density Function(TPDF) turbulence combustion model is promising in engineering applications. In flame region, the impact of chemical reaction should be considered in TPDF molecular mixing model. Based on pioneer research, three new TPDF turbulence-chemistry dual time scale molecular mixing models were proposed tentatively by adding the chemistry time scale in molecular mixing model for nonpremixed flame. The Aero-Engine Combustor Simulation Code(AECSC) which is based on LES-TPDF method was combined with the three new models. Then the Sandia laboratory's methane-air jet flames: Flame D and Flame E were simulated. Transient simulation results show that all the three new models can predict the instantaneous combustion flow pattern of the jet flames. Furthermore,the average scalar statistical results were compared with the experimental data. The simulation result of the new TPDF arithmetic mean modification model is the closest to the experimental data:the average error in Flame D is 7.6% and 6.6% in Flame E. The extinction and re-ignition phenomena of the jet flames especially Flame E were captured. The turbulence time scale and the chemistry time scale are in different order in the whole flow field. The dual time scale TPDF combustion model has ability to deal with both the turbulence effect and the chemistry reaction effect, as well as their interaction more accurately for nonpremixed flames.

关键词： Dual time scale model Large eddy simulation Sandia methane-air jet flame TPDF molecular mixing model Turbulence combustion model

Investigation and analysis of a fluidized bed dryer by process tomography sensor

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Petroleum Science 2020年第2期17卷 525-536页

作者： Hai-Gang Wang Yong-Lei Lin Wu-Qiang Yang Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China School of Electrical and Electronic Engineering University of ManchesterManchester M139PLUK

In the pharmaceutical industry,fluidized beds are typically used for pellets drying,coating and *** gas-solids flow characteristic in the process plays an important role to control the heat and mass transfer as well as the end-point product ***,it is necessary to investigate the flow characteristics based on advanced measurement *** this research,electrical capacitance tomography(ECT)sensor with eight electrodes was used to investigate the pharmaceutical fluidized bed drying process with different operation *** process parameters including solids concentration,particle moisture and capacitance signals in the process are given and analysed based on the ECT *** addition,the fluidized bed process with Wurster tube is also investigated based on this ECT *** effect of Wurster tube on the hydrodynamic behaviour and the dominant frequency spectrum distribution in the chamber were analysed based on fast Fourier *** results reveal that process moisture change can be addressed from the raw capacitance of adjacent electrode pair combined with calibration *** result also indicates that ECT technology can provide useful information for process monitor in a fluidized bed dryer.

关键词： Fluidized bed Drying Wurster tube Moisture Process tomography

A computational model for assessment of speech intelligibility in informational masking

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Frontiers of Electrical and Electronic Engineering in China 2012年第1期7卷 107-115页

作者： Xihong WU Jing CHEN Speech and Hearing Research Center Key Laboratory of Machine Perception(Ministry of Education)Peking UniversityBeijing 100871China

The existing auditory computational mod- els for evaluating speech intelligibility can only account for energetic masking, and the effect of informational masking is rarely described in these models. This study was aimed to make a computational model considering the mechanism of informational masking. Several psy- choacoustic experiments were conducted to test the ef- fect of informational masking on speech intelligibility by manipulating the number of masking talker, speech rate, and the similarity of F0 contour between target and masker. The results showed that the speech recep- tion threshold for the target increased as the F0 contours of the masker became more similar to that of the tar- get, suggesting that the difficulty in segregating the tar- get harmonics from the masker harmonics may underlie the informational masking effect. Based on these stud- ies, a new auditory computational model was made by inducing the auditory function of harmonic extraction to the traditional model of speech intelligibility index （SII）, named as harmonic extraction （HF） model. The predictions of the HF model are highly consistent with the experimental results.

关键词： auditory computational model speech intelligibility informational masking F0 contour harmonic extraction

The genomes of medicinal skullcaps reveal the polyphyletic origins of clerodane diterpene biosynthesis in the family Lamiaceae

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Molecular Plant 2023年第3期16卷 549-570页

作者： Haixiu Li Song Wu Ruoxi Lin Yiren Xiao Ana Luisa Malaco Morotti Ya Wang Meytal Galilee Haowen Qin Tao Huang Yong Zhao Xun Zhou Jun Yang Qing Zhao Angelos K.Kanellis Cathie Martin Evangelos C.Tatsis National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China University of Chinese Academy of Sciences Beijing 100049China Novogene Bioinformatics Institute BeijingChina Shanghai Key Laboratory of Plant Functional Genomics and Resources Shanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghai 201602 Group of Biotechnology of Pharmaceutical Plants Lab.of PharmacognosyDepartment of Pharmaceutical SciencesAristotle University of Thessaloniki54124 ThessalonikiGreece John Innes Centre Norwich NR47UHUK CEPAMS-CAS-JIC Centre of Excellence for Plant and Microbial Sciences Shanghai 200032China

The presence of anticancer clerodane diterpenoids is a chemotaxonomic marker for the traditional Chinese medicinal plant Scutellaria barbata,although the molecular mechanisms behind clerodane biosynthesis are ***,we report a high-quality assembly of the 414.98 Mb genome of *** into 13 *** phylogenomic and biochemical data,we mapped the plastidial metabolism of kaurene(gibberellins),abietane,and clerodane diterpenes in three species of the family Lamiaceae(Scutellaria barbata,Scutellaria baicalensis,and Salvia splendens),facilitating the identification of genes involved in the biosynthesis of the clerodanes,kolavenol,and *** show that clerodane biosynthesis evolved through recruitment and neofunctionalization of genes from gibberellin and abietane *** the assumed monophyletic origin of clerodane biosynthesis,which is widespread in species of the Lamiaceae,our data show distinct evolutionary lineages and suggest polyphyletic origins of clerodane biosynthesis in the family *** study not only provides significant insights into the evolution of clerodane biosynthetic pathways in the mint family,Lamiaceae,but also will facilitate the production of anticancer clerodanes through future metabolic engineering efforts.

关键词： Scutellaria barbata genome clerodane diterpenoids biosynthesis specialized metabolism evolution

Supramolecular precursor strategy for the synthesis of holey graphitic carbon nitride nanotubes with enhanced photocatalytic hydrogen evolution performance

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Nano Research 2019年第9期12卷 2385-2389页

作者： Xiaoshuai Wang Chao Zhou Run Shi Qinqin Liu Geoffrey I. N. Waterhouse Lizhu Wu Chen-Ho Tung Tierui Zhang Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China School of Chemical Sciences The University of AucklandAuckland 1142New Zealand

A simple one-step thermal polymerization method was developed for synthesis of holey graphitic carbon nitride nanotubes,involving direci eating of mixtures of melamine and urea or melamine and cyanuric acid in specific mass *** structures formed betweer the precursor molecules guided nanotube *** porous and nanotubular structure of the nanotubes facilitated efficient charge carrier nigration and separation,thereby enhancing photocatalytic Hz production in 20 vol.%lactic acid under visible light *** synthesized using melamine and urea in a 1:10 mass ratio(denoted herein as CN-MU nanotubes)exhibited a photocatalytic hydroger production rate of 1,073.6μmol·h^-1·^-g with Pt as the cocatalyst,a rate of 4.7 and 3.1 times higher than traditional Pt/g-CN4 photocatalysts prepared from graphitic carbon nitride(g-CN4)obtained by direct thermal polymerization of melamine or urea,*** the basis of their outstanding performance for photocatalytic H2 production,it is envisaged that the holey g-C3N4 nanotubes will find widespread uptake in other areas,including photocatalytic CO2 reduction,dye-sensitized solar cells and photoelectrochemical sensors.

关键词： graphitic carbon nitride holey nano tubes photocatalysis visible-light response hydroge n evolution

Selective photocatalytic CO2 reduction over Zn-based layered double hydroxides containing tri or tetravalent metals

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Science Bulletin 2020年第12期65卷 987-994,M0003页

作者： Xuyang Xiong Yufei Zhao Run Shi Wenjin Yin Yunxuan Zhao Geoffrey I.N.Waterhouse Tierui Zhang Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academmy of SciencesBeijing WO 190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China School of Physics and Electronic Science Hunan University of Science and TechnologyXiangtan 411201China School of Chemical Sciences The University of AucklandAuckland 1142New Zealand

Photocatalytic CO2 reduction holds promise as a future technology for the manufacture of fuels and commodity ***,factors controlling product selectivity remain poorly ***,we compared the performance of a homologous series of Zn-based layered double hydroxide(ZnM-LDH)photocatalysts for CO2 *** varying the trivalent or tetravalent metal cations in the ZnM-LDH photocatalysts(M=Ti4+,Fe3+,Co3+,Ga3+,Al3+),the product selectivity of the reaction could be precisely ***-LDH afforded CH4 as the main reduction product;ZnFe-LDH and ZnCo-LDH yielded H2 exclusively from water splitting;whilst ZnGa-LDH and ZnAl-LDH generated ***-situ diffuse reflectance infrared measurements,valence band XPS and density function theory calculations were applied to rationalize the CO2 reduction selectivities of the different ZnM-LDH *** analyses revealed that the d-band center(ed)position of the M3+or M4+cations controlled the adsorption strength of CO2 and thus the selectivity to carbon-containing products or *** with d-band centers relatively close to the Fermi level(Ti4+,Ga3+and Al3+)adsorbed CO2 strongly yielding CH4 or CO,whereas metal cations with d-band centers further from the Fermi level(Fe3+and Co3+)adsorbed CO2 poorly,thereby yielding H2 only(from water splitting).Our findings clarify the role of trivalent and tetravalent metal cations in LDH photocatalysts for the selective CO2 reduction,paving new ways for the development of improved LDH photocatalyst with high selectivities to specific products.

关键词： Photocatalytic CO2 reduction Layered double hydroxide Selectivity Tri/tetravalent metal cations d band center

Diterpenoids from Scutellaria barbata induce tumour-selective cytotoxicity by taking the brakes off apoptosis

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Medicinal Plant Biology 2022年第1期1卷 8-23页

作者： Matthew L.Tomlinson Man Zhao Elaine J.Barclay Jie Li Haixiu Li Juri Felix Lionel Hill Gerhard Saalbach Martin Rejzek Dongfeng Yang Qing Zhao Paul Kroon Wei Wang Yongping Bao Melanie-Jayne R.Howes Evangelos C.Tatsis Cathie Martin The John Innes Centre NorwichNR47UHUnited Kingdom College of Bioengineering and Biotechnology Zhejiang University of TechnologyHangzhou 310058China National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China royal Botanic Gardens Kew RichmondSurreyLondon TW93ABUnited Kingdom College of Life Sciences Zhejiang Sci-Tech UniversityXiasha Higher Education ZoneHangzhou 310018China Shanghai Key Laboratory of Plant Functional Genomics and Resources Shanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghai 201602China Quadram Institute Bioscience Norwich Research ParkNorwichNR47UAUnited Kingdom Norwich Medical School University of East AngliaNorwichNorfolkNR47TJUnited Kingdom CEPAMS:CAS-JIC Centre of Excellence in Plant and Microbial Sciences

Medicinal plants are an excellent source of structurally diverse,bio-active compounds with potential in the fight against *** of the most promising is Scutellaria barbata,prescribed traditionally for the treatment of *** A is the major diterpenoid,produced in specialized large,peltate trichomes on leaves of *** induces dose-dependent apoptosis,specifically in cancer *** major class of proteins down-regulated are pro-survival proteins,the Inhibitors of Apoptosis(IAPs),and IAP regulating *** propose that scutebarbatine A works by releasing the molecular brakes(the IAPs)on apoptosis in cell death-evading cancer *** between the cytotoxicity of methanolic extracts of *** leaves and decoctions(Ban Zhi Lian)prepared traditionally,showed substantially different chemical compositions and differential induction of *** suggest polyvalency between the constituents in both extracts,and ways to produce enhanced chemopreventive preparations for the treatment of cancer.

关键词： prescribed methanol structurally

Printable organic light-emitting diodes for next-generation visible light communications:a review

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Advanced Photonics Nexus 2023年第4期2卷 1-14页

作者： Kunping Guo Zhe Tang Xingxing Chou Saihu Pan Chunchen Wan Tao Xue Liping Ding Xiao Wang Jin Huang Fanghui Zhang Bin Wei Shaanxi University of Science and Technology School of Electronic Information and Artificial IntelligenceXi’anChina University College London Department Physics and Astronomy and London Centre for NanotechnologyLondonUnited Kingdom Shaanxi University of Science and Technology School of Electrical and Control EngineeringXi’anChina Changzhou University School of Microelectronics and Control EngineeringChangzhouChina Shanghai University Ministry of EducationKey Laboratory of Advanced Display and System ApplicationsShanghaiChina

Visible light communication(VLC)is an emerging technology employing light-emitting diodes(LEDs)to provide illumination and wireless data transmission *** cost-efficient printable organic LEDs(OLEDs)as environmentally friendly transmitters in VLC systems is extremely attractive for future applications in spectroscopy,the internet of things,sensing,and optical ranging in ***,we summarize the latest research progress on emerging semiconductor materials for LED sources in VLC,and highlight that OLEDs based on nontoxic and cost-efficient organic semiconductors have great opportunities for optical *** further examine efforts to achieve high-performance white OLEDs for general lighting,and,in particular,focus on the research status and opportunities for OLED-based *** solution-processable fabrication and printing strategies to develop high-performance OLEDs are also ***,an outlook on future challenges and potential prospects of the next-generation organic VLC is provided.

关键词： organic light-emitting diode visible light communication printable vehicular applications internet of things