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Studies on sulfinatodehalogenation——ⅩⅪ.A new and convenient syntheses of 2-(F-alkyl)aldehydes,alcohols,acids and ketones

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Chinese Journal of Chemistry 1991年第2期9卷 174-180页

作者： huang Wei-yuan Shanghai Institute of Organic Chemistry The Chinese Academy of SciencesShanghai 200032

Reaction of perfluoroalkyl iodides(1a—e)with the unsaturated ethers such as 1-ethoxy-1- propene(2),1-methoxy-1-butene(3)under the sulfinatodehalogenation condition gave the correspon- ding 2-(F-alkyl)propanals(5a—e)and butanals(6c,d)very readily in high yield,which were converted to 2,4-dinitrophenylhydrazones(7a—e,8c,d)and *** reaction products 5 and 6 were oxidized with Jone's reagent and reduced with NaBH_4 in ethanol to give the corresponding acids (9,10)and alcohols(11,12)in good *** of compounds 5 and 6 with pyridine gave the dehydrofluorination products 13 and *** the same condition,perfluoroalkyl iodide reacted with 2-ethoxy-1-propene(4)only to form R_FSO_2Na and R_FH as the major products,but in aqueu- ous DMF(DMF:H_2O=5:1)to give the perfluoroalkylacetone(15)in good ***,the reac- tion provides a convenient,effective new method for syntheses of these useful organofluorine inter- mediates.

关键词： F-alkyl)aldehydes,alcohols,acids and ketones A new and convenient syntheses of 2

In situ direct reprogramming of astrocytes to neurons via polypyrimidine tract-binding protein 1 knockdown in a mouse model of ischemic stroke

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Neural Regeneration Research 2024年第10期19卷 2240-2248页

作者： Meng yuan Yao Tang Tianwen huang Lining Ke En huang Key Laboratory of Brain Aging and Neurodegenerative Diseases of Fujian Province Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Human Anatomy School of Basic Medical SciencesFujian Medical UniversityFuzhouFujian ProvinceChina Scientific Research Center School of Basic Medical SciencesFujian Medical UniversityFuzhouFujian ProvinceChina Department of Neurology Fujian Medical University Union HospitalFuzhouFujian ProvinceChina Fujian Key Laboratory of Vascular Aging Fujian Medical UniversityFuzhouFujian ProvinceChina

In situ direct reprogramming technology can directly convert endogenous glial cells into functional neurons in vivo for central nervous system repair. Polypyrimidine tract-binding protein 1(PTB) knockdown has been shown to reprogram astrocytes to functional neurons in situ. In this study, we used AAV-PHP.e B-GFAP-sh PTB to knockdown PTB in a mouse model of ischemic stroke induced by endothelin-1, and investigated the effects of GFAP-sh PTB-mediated direct reprogramming to neurons. Our results showed that in the mouse model of ischemic stroke, PTB knockdown effectively reprogrammed GFAP-positive cells to neurons in ischemic foci, restored neural tissue structure, reduced inflammatory response, and improved behavioral function. These findings validate the effectiveness of in situ transdifferentiation of astrocytes, and suggest that the approach may be a promising strategy for stroke treatment.

关键词： astrocyte in situ direct reprogramming ischemic stroke miR-30 based shRNA neuron polypyrimidine tract-binding protein 1 transdifferentiation

The solution and exsolution characteristics of natural gas components in water at high temperature and pressure and their geological meaning

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Petroleum Science 2012年第1期9卷 25-30页

作者： Gao Gang huang Zhilong huang Baojia yuan Jian Tong Chuanxin State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumBeijing 102249China Exploration and Development Research Institutes CNOOC ZhanjiangGuangdong 524057China Chuanxi Production Factory Southwest Oil and Gas Field BranchSINOPECDeyangSichuan 618000China

The processes of solution in, and exsolution from, formation water influence the component content of natural gas by contrasting the relative contents of components before the natural gas dissolves in water and those after exsolving from water under different conditions of high temperatures and pressures. Compared with the composition of original natural gas, the relative content of methane and nitrogen increased after the natural gas dissolved in water. The increase of nitrogen content exceeds that of methane, but the content of ethane, propane, pentane etc reduced. At the same temperature and with pressure increasing the content of methane increased and that of heavier hydrocarbons reduced. At the same pressure the content of methane increased quickly from 90~C to 120~C, and the content of heavier hydrocarbons reduced. But at even higher temperatures, the increase of methane slowed down and the content of heavier hydrocarbons increased slightly. At the same temperature and different pressures, heavier hydrocarbons reduced much more with increasing carbon atom number, while with temperature increasing the content difference of heavier hydrocarbons reduced. Therefore, the influence of the solution and exsolution should be considered in the study of the migration and accumulation mechanism of natural gas.

关键词： Methane heavier hydrocarbon nitrogen formation water exsolution

Locations of Sonic Points in Advection Dominated Accretion Flows Around Black Holes

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Chinese Physics Letters 1999年第4期16卷 310-312页

作者： yuan Feng huang Ke-liang Department of Astronomy Nanjing UniversityNanjing 210093 Department of Physics Nanjing Normal UniversityNanjing 210097

The global transonic solutions describing advection dominated accretion flows around black holes are obtained by directly integrating the set of differential equations from the sonic point inward to the horizon and *** results show that the sonic points can locate themselves at almost any radius,regardless of the viscous parameter a and polytropic indexγ.This result is greatly different with previous *** solutions with very different values of R_(s)from 4.3 to 300R_(g) and withγ=1.5,5/3 are given *** consistency between this result and that in inviscid flows is emphasized.

关键词： flows integrating radius

Identification of cytokine via an improved genetic algorithm

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Frontiers of Computer Science 2015年第4期9卷 643-651页

作者： Xiangxiang ZENG Sisi yuan Xianxian huang Quan ZOU Department of Computer Science Xiamen University Xiamen 361005 China

With the explosive growth in the number of pro- tein sequences generated in the postgenomic age, research into identifying cytokines from proteirls and detecting their biochemical mechanisms becomes increasingly important. Unfortunately, the identification of cytokines from proteins is challenging due to a lack of understanding of the struc- ture space provided by the proteins and the fact that only a small number of cytokines exists in massive proteins. In view of fact that a proteins sequence is conceptually similar to a mapping of words to meaning, n-gram, a type of probabilistic language model, is explored to extract features for proteins. The second challenge focused on in this work is genetic algo- rithms, a search heuristic that mimics the process of natural selection, that is utilized to develop a classifier for overcom- ing the protein imbalance problem to generate precise pre- diction of cytokines in proteins. Experiments carded on im- balanced proteins data set show that our methods outperform traditional algorithms in terms of the prediction ability.

关键词： n-grams genetic algorithm cytokine identifica-tion sampling imbalanced data

Adsorption mechanisms of PFOA onto activated carbon anchored with quaternary ammonium/epoxide-forming compounds: A combination of experiment and model studies

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Journal of Environmental Sciences 2020年第12期32卷 94-102页

作者： Chen yuan Yang huang Fred SCannon Zhiwei Zhao Shenzhen Academy of Environmental Science Shenzhen 518001China College of Urban Construction and Environmental Engineering Chongqing UniversityChongqing 400045China Department of Civil and Environmental Engineering Pennsylvania State UniversityUniversity ParkPA 16802USA College of Resources and Environment Chengdu University of Information TechnologyChengdu 610225China

When wood-based activated carbon was tailored with quaternary ammonium/epoxide(QAE) forming compounds(QAE-AC), this tailoring dramatically improved the carbon's effectiveness for removing perfluorooctanoic acid(PFOA) from groundwater. With favorable tailoring, QAE-AC removed PFOA from groundwater for 118,000 bed volumes before halfbreakthrough in rapid small scale column tests, while the influent PFOA concentration was 200 ng/L. The tailoring involved pre-dosing QAE at an array of proportions onto this carbon, and then monitoring bed life for PFOA removal. When pre-dosing with 1 mL QAE, this PFOA bed life reached an interim peak, whereas bed life was less following 3 mL QAE pre-dosing, then PFOA bed life exhibited a steady rise for yet subsequently higher QAE pre-dosing levels. Large-scale atomistic modelling was used herein to provide new insight into the mechanism of PFOA removal by QAE-AC. Based on experimental results and modelling, the authors perceived that the QAE's epoxide functionalities cross-linked with phenolics that were present along the activated carbon's graphene edge sites, in a manner that created mesopores within macroporous regions or created micropores within mesopores regions. Also, the QAE could react with hydroxyls outside of these pore, including the hydroxyls of both graphene edge sites and other QAE molecules. This latter reaction formed new pore-like structures that were external to the activated carbon grains. Adsorption of PFOA could occur via either charge balance between negatively charged PFOA with positively charged QAE, or by van der Waals forces between PFOA's fluoro-carbon tail and the graphene or QAE carbon surfaces.

关键词： Perfluorooctanoic acid Nitrate Carbon Atomistic model Adsorption mechanism

Building metallurgical bonding interfaces in an immiscible Mo/Cu system by irradiation damage alloying (IDA)

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Journal of Materials Science & Technology 2018年第4期34卷 689-694页

作者： Jinlong Du yuan huang Chan Xiao Yongchang Liu Tianjin Key Laboratory of Composite and Functional Materials School of Material Science and Engineering Tianjin University

For the immiscible Mo/Cu system with a positive heat of mixing （△Hm 〉 0）, building metallurgical bonding interfaces directly between immiscible Mo and Cu and preparing Mo/Cu laminar metal matrix composites （LMMCs） are very difficult. To solve the problem, a new alloying method for immiscible systems, which is named as irradiation damage alloying （IDA）, is presented in this paper. The IDA primarily consists of three steps. Firstly, Mo is damaged by irradiation with multi-energy （186, 62 keV） Cu ion beams at a dose of 2× 1017 ions/cm2. Secondly, Cu layers are superimposed on the surfaces of the irradiation-damaged Mo to obtain Mo]Cu laminated specimens. Thirdly, the irradiation damage induces the diffusion alloying between Mo and Cu when the laminated specimens are annealed at 950 ℃ in a protective atmosphere. Through IDA, Mo/Cu LMMCs are prepared in this paper. The tensile tests carried out for the Mo/Cu LMMCs specimens show that the Mo/Cu interfaces constructed via IDA have high normal and shear strengths. Additionally, the microstructure of the Mo/Cu interface is characterized by High Resolution Transmission Electron Microscopy （HRTEM）, X-ray diffraction （XRD） and Energy Dispersive X-ray （EDX） attached in HRTEM. The microscopic characterization results show that the expectant diffusion between Mo and Cu occurs through the irradiation damage during the process of IDA. Thus a Mo/Cu metallurgical bonding interface successfully forms. Moreover, the microscopic test results show that the Mo/Cu metallurgical interface is mainly constituted of crystalline phases with twisted and tangled lattices, and amorphous phase is not observed. Finally, based on the positron annihilation spectroscopy （PAS） and HRTEM results, the diffusion mechanism of IDA is discussed and determined to be vacancy assisted diffusion.

关键词： Mo/Cu immiscible system Irradiation damage alloying Metallurgical bonding interface Ion implantation Laminar metal matrix composites

A NUMERICAL ANALYSIS OF THE VENTILATION PERFORMANCE FOR DIFFERENT VENTILATION STRATEGIES IN A SUBWAY TUNNEL

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Journal of Hydrodynamics 2012年第2期24卷 193-201页

作者： huang yuan-dong LI Chan KIM Chang Nyung School of Environment and Architecture University of Shanghai for Science and Technology China College of Engineering Kyung Hee University Yongin 449-701 Korea Graduate School Kyung Hee University Yongin 449-701 Korea Industrial Liaison Research Institute Kyung Hee University Yongin 449-701 Korea

An unsteady three-dimensional analysis of the ventilation performance is carried out for different ventilation strategies to find out a ventilation method with a high performance in a subway *** natural ventilation performance associated with a train-induced air flow in a subway tunnel is *** dynamic layering method is used to consider the moving boundary of a train in the current CFD *** geometries of the modeled tunnel and the subway train are partially based on those of the Seoul *** effects of the structure of the ventilation duct and the geometry of the partitions on the ventilation performance are *** results show that the combined ventilation ducts （to be designed）,and the partitioning blocks installed along the middle of tunnel （already in existences） are helpful for air *** study can provide some guidance for the design of ventilation ducts in a subway system.

关键词： ventilation performance subway tunnel train-induced air flow natural ventilation duct numerical analysis

3D FEM Analyses on Flow Field Characteristics of the Valveless Piezoelectric Pump

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Chinese Journal of Mechanical Engineering 2016年第4期29卷 825-831页

作者： huang Jun ZHANG Jianhui SHI Weidong WANG yuan National Research Center of Pumps Jiangsu University School of Mechanical and Electric Engineering Guangzhou University State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics College of Communication Engineering PLA University of Science and Technology

Due to the special transportation and heat transfer characteristics,the fractal-like Y-shape branching tube is used in valveless piezoelectric pumps as a no-moving-part ***,there have been little analyses on the flow resistance of the valveless piezoelectric pump,which is critical to the performance of the valveless piezoelectric pump with fractal-like Y-shape branching *** field of the piezoelectric pump is analyzed by the finite element method,and the pattern of the velocity streamlines is revealed,which can well explain the difference of total flow resistances of the piezoelectric ***,simplified numerical method is employed to calculate the export flow rate of piezoelectric pump,and the flow field of the piezoelectric pump is *** FEM computation shows that the maximum flow rate is 16.4 m L/*** with experimental result,the difference between them is just 55.5%,which verifies the FEM *** reasons of the difference between dividing and merging flow resistance of the valveless piezoelectric pump with fractal-like Y-shape branching tubes are also investigated in this *** proposed research provides the instruction to design of novel piezoelectric pump and a rapid method to analyse the pump flow rate.

关键词： piezoelectric pump valveless fractal-like Y-shape branching tube FEM