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Magnetically assisted fluorescence ratiometric assays for adenosine deaminase using water-soluble conjugated polymers

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Chinese Science Bulletin 2009年第8期54卷 1340-1344页

作者： HE Fang yu minghui WANG Shu Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic Solids institute of Chemistry Chinese Academy ofSciences Beijing 100190 China

A magnetically assisted fluorescence ratiometric technique has been developed for adenosine deaminase assays with high sensitivity using water-soluble cationic conjugated polymers(CCPs).The assay contains three elements:a biotin-labeled aptamer of adenosine(biotin-aptamer),a signaling probe single-stranded DNA-tagged fluorescein at terminus(ssDNA-Fl) and a *** specific binding of adenosine to biotin-aptamer makes biotin-aptamer and ssDNA-Fl unhybridized,and the ssDNA-Fl is washed out after streptavidin-coated magnetic beads are added and separated from the assay solution under magnetic *** this case,after the addition of CCP to the magnetic beads solution,the fluo-rescence resonance energy transfer(FRET) from CCP to fluorescein is *** adding adenosine deaminase,the adenosine is converted into inosine,and the biotin-aptamer is hybridized with ssDNA-Fl to form doubled stranded DNA(biotin-dsDNA-Fl).The ssDNA-Fl is attached to the mag-netic beads at the separation step,and the addition of CCP to the magnetic beads solution leads to efficient FRET from CCP to *** the adenosine deaminase activity can be monitored by fluorescence spectra in view of the intensity decrease of CCP emission or the increase of fluorescein emission in aqueous *** assay integrates surface-functionalized magnetic particles with significant amplification of detection signal of water-soluble cationic conjugated polymers.

关键词：腺苷脱氨酶共轭聚合物荧光素水溶性荧光共振能量转移单链DNA 生物素标记检测灵敏度

Investigation of Ce/BEA as a passive NO_(x)adsorber:*** occurrences of cerium and adsorption behavior

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Journal of Rare Earths 2024年第7期42卷 1265-1271,I0003页

作者： minghui yu Yiying Ding Xiaojie yu Siwei Yan Meiqing Shen Jianqiang Wang Jun Wang Gurong Shen School of Materials Science and Engineering Tianjin UniversityTianjin300350China School of Chemical Engineering and Technology Tianjin UniversityTianjin300350China National Rare Earth Catalysis Research Institute Dongying257000China

Ce/BEA has great potential as a passive NO_(x)absorber(PNA)to reduce the NO_(x)emissions during the cold start phase especially in diesel engine for its high resistance to CO and suitable NO_(x)desorption temperature ***,as a novel material,its physical and chemical properties still remain *** this work,Ce/BEA was synthesized by ion-exchange method to identify the active species in NO_(x)adsorption,compared with aggregated Ce species in Ce/SiAlO_(x) prepared by impregnation method.X-ray diffraction(XRD),high resolution-transmission electron microscopy(HR-TEM)and aberration-corrected-scanning transmission electron microscopy(AC-STEM)were performed to confirm the isolated single atom formation of Ce species in Ce/***-vis diffraction reflection spectra(DRS)and X-ray photoelectron spectroscopy(XPS)were conducted to find the difference of chemical environment between the isolated Ce species and aggregated *** performance evaluation and temperature programmed reduction of hydrogen(H_(2)-TPR)results show the high NO_(x)storage capacity and active oxygen species quantity in Ce/*** is also found that the main NO_(x)adsorption species are Ce^(4+)-O^(∗)rather than Ce^(3+).NO_(x)-diffuse reflectance infrared Fourier transform spectroscopy(NO_(x)-DRIFTS)confirms that the bidentate nitrite species are the critical NO_(x)adsorption intermediates and the conception of NO_(x)adsorption and desorption processes is proposed.

关键词： Passive NO_(x)absorber Ce/BEA Isolated Ce species Rare earths

The mathematical model of kitchen smoke exhaust system in high-rise residential buildings considering the Influence of Stack effect

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Energy and Built Environment 2024年第4期5卷 580-591页

作者： Kailiang Huang minghui yu Xin Liu Runsheng Wang School of Municipal and Environment Engineering Shenyang Jianzhu UniversityShenyang100168China

In high-rise buildings with large indoor and outdoor temperature difference,neglecting the effect of stack effect in smoke exhaust shafts may cause calculation error of the fluid network *** this paper,the mathematical model of kitchen smoke exhaust system considering the influence of stack effect was put forward and it can be inserted different range hood *** with the results of six working conditions of the model without considering the stack effect,the error of the proposed model were reduced by 7.6%,4.3%,4.1%,2.8%,2.4%,and 2.1%.While the indoor and outdoor temperature difference varies from−5℃ to 49℃,the effect of stack effect on the pressure in the flue and the flow rate for each user was studied for six operating rates *** results show that under the combined effect of stack effect and flue resistance,the static pressure of the kitchen smoke exhaust system showed a low-high-low distribution,and the maximum static pressure in the flue moved toward the bottom with the increase of temperature *** flow rates exhibit a low-high-low-high distribution,with an increased flow rate in the bottom users and the largest flow rate in the top users.

关键词： High-rise residential buildings Kitchen ventilation Central exhaust system Buoyancy-driven ventilation Ventilation mathematical model

Statistics-based Optimization of the Polarimetric Radar Hydrometeor Classification Algorithm and Its Application for a Squall Line in South China

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Advances in Atmospheric Sciences 2018年第3期35卷 296-316页

作者： Chong WU Liping LIU Ming WEI Baozhu XI minghui yu Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and Technology Nanjing 210044 China State Key Lab of Severe Weather Chinese Academy of Meteorological Science Beijing 100081 China

A modified hydrometeor classification algorithm （HCA） is developed in this study for Chinese polarimetric radars. This algorithm is based on the U.S. operational HCA. Meanwhile, the methodology of statistics-based optimization is proposed including calibration checking, datasets selection, membership functions modification, computation thresholds modification, and effect verification. Zhuhai radar, the first operational polarimetric radar in South China, applies these procedures. The systematic bias of calibration is corrected, the reliability of radar measurements deteriorates when the signal-to-noise ratio is low, and correlation coefficient within the melting layer is usually lower than that of the U.S. WSR-88D radar. Through modification based on statistical analysis of polarimetric variables, the localized HCA especially for Zhuhai is obtained, and it performs well over a one-month test through comparison with sounding and surface observations. The algorithm is then utilized for analysis of a squall line process on 11 May 2014 and is found to provide reasonable details with respect to horizontal and vertical structures, and the HCA results---especially in the mixed rain-hail region--can reflect the life cycle of the squall line. In addition, the kinematic and microphysical processes of cloud evolution and the differences between radar- detected hail and surface observations are also analyzed. The results of this study provide evidence for the improvement of this HCA developed specifically for China.

关键词： dual polarization radar hydrometeor classification fuzzy logic scheme

Non-symmetrical levee breaching processes in a channel bend due to overtopping

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International Journal of Sediment Research 2018年第2期33卷 208-215页

作者： Songbai Wu minghui yu Hongyan Wei Yanjie Liang Jing Zeng State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Institute of Earth Surface System and Hazards Northwest University Yellow River Engineering Consulting Co. Ltd.

A series of experiments were done to reveal the overtopping breaching process of non-cohesive and cohesive levees in a U-bend flume. The flood hydrograph and breaching geometry were measured and analyzed in detail. The results show that the levee breaching processes can be briefly divided into four stages: slope erosion, longitudinal headward gully-cutting, lateral erosion, and relative stabilization. For non-cohesive levees, non-symmetrical lateral development of the breach occurs throughout the four stages, and the final non-symmetrical coefficient is approximately 2.2-2.6. Larger flow discharge or higher water level can accelerate the breaching process, while coarser sands tend to accelerate the process initially but depress the process at the end. The fluvial erosion rate of a non-cohesive breach shows a power-function relation with the excess wall shear stress. For cohesive levees, a plateau forms in the breach partially blocking the flow in the first two stages. The breach flow is approximately perpendicular to the levee body, and, thus, the erosion rates of the two breach sides are almost the ***-symmetrical lateral development mainly occurs in the third stage when the deep gully forms. The final non-symmetrical coefficient is approximately 2.7-3.3. It is expected that these findings can provide a valuable experimental dataset and a theoretical basis for breach closure and flood alleviation.

关键词： Overtopping Levee breach Hydrodynamic model Flume experiment

A novel material for passive NO_(x) adsorber:Ce-based BEA zeolite

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Journal of Rare Earths 2023年第8期41卷 1163-1170,I0002页

作者： Yan Wu Jun Wang Zexiang Chen Yi Zhu minghui yu Chen Wang Yanping Zhai Jianqiang Wang Gurong Shen Meiqing Shen School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China National Rare Earth Catalysis Research Institute Dongying 257000China Department of Environmental Engineering and Technology China Institute for Radiation ProtectionTaiyuan 030006China School of Materials Science and Engineering Tianjin UniversityTianjin 300350China School of Environmental and Safety Engineering North University of ChinaTaiyuan 030051China Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) Tianjin 300350China

Passive NO_(x) adsorbers(PNAs)were proposed to address the NO_(x) emissions during the cold start *** we show a novel Ce-based BEA zeolite,as a noble-metal-free passive NO_(x)*** NO_(x) adsorption capacity of Ce/BEA reaches 36μmol/g in the feed gas close to realistic exhaust conditions,and the NO_(x) desorption temperature,which is around 290℃,is ideal for diesel exhaust after-treatment ***/BEA also behaves notable stability of high temperature CO exposure *** characterizations were performed to explore the NO_(x) adsorption chemistry of Ce/*** Ce(Ⅳ)species in the BEA zeolite serves as the active center for NO_(x) *** bidentate nitrate species is responsible for the observed NO_(x) storage capacity,and the active oxygen around Ce(Ⅳ)plays a critical role in its *** the significantly better cost efficiency of Ce compared to Pd,Ce/BEA presents an enormous potential for the PNA applications and provides a novel formulation for the noblemetal choice of PNA materials.

关键词： Passive NO_(x)adsorbers Ce/BEA Non-noble-metal Cold start Rare earths

Effects of Post-Heat Treatment and Carbide Precipitates on Strength-Ductility Balance of GH3536 Superalloy Prepared by Selective Laser Melting

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Acta Metallurgica Sinica(English Letters) 2024年第10期37卷 1667-1679页

作者： Le Xia Haijun Su Quandong Hu Yinuo Guo Peixin Yang Hongliang Gao minghui yu Min Guo Zhuo Zhang Lin Liu Hengzhi Fu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an710072China Research and Development Institute of Northwestern Polytechnical University in ShenzhenShenzhen518057China Science and Technology on Power Beam Processes Laboratory AVIC Manufacturing Technology InstituteBeijing100024China

The strength and ductility cannot achieve a good tradeoff for some superalloy(***3536)prepared by selective laser melting(SLM),which seriously restricts their industrial *** work examined the effect of post-heat treatment(HT)on the microstructure and mechanical properties of GH3536 produced by *** particular,the influence of carbide precipitate morphology and distribution on strength and ductility of the alloy after heat treatment was *** aging at 650°C(denoted as HT1),the Cr23C6 carbides were distributed in *** ductility increased by approximately 31%,while the strength slightly *** aging at 745°C(denoted as HT2),the Cr23C6 carbides were distributed in ***,the HT2 samples showed an increase in ductility of~58%and no reduction in *** the dislocation density of HT2 sample was higher than that of the HT1 sample,the chain carbides could be pinned to the grain boundaries,consequently improving the ductility but no loss in strength as compared with the as-deposited *** the aging temperature was increased to 900°C(denoted as HT3),the carbides were distributed in a discontinuous granular *** a result,the HT3 samples presented the lowest dislocation density which reduced the strength.

关键词： Selective laser melting GH3536 Heat treatment Carbides Strength-ductility

A HORIZONTAL 2-D HYDRAULIC NUMERICAL MODEL AND IT’S APPLICATIONS TO FLOOD FORECAST

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International Journal of Sediment Research 2002年第3期17卷 250-255页

作者： minghui yu Guolu YANG Jinjun XU China Lab.ofSediment Engineering School of Geomatics and Geodesy Wuhan 430071 Wuhan 430072 Wuhan University

In this paper, a horizontal 2-D numerical model has been developed to simulate flow processes in dike burst. The finite difference method is used in computation. The model employs 2-D flow equations and can simulate complex flows when supercritical flow and sub-critical flow exist simultaneously such as hydraulic jumps. Several simulated results are worked out to demonstrate the applicability of the numerical model, such as flood propagation on a dry bed of a complex terrain.

关键词： Key Word: Numerical scheme Flood Complex terrain Adjoint method

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崩塌体水力输移与塌岸淤床交互影响试验

水科学进展 2014年第5期25卷 677-683页

作者：余明辉郭晓武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072 中国长江电力股份有限公司三峡水利枢纽梯级调度通信中心湖北宜昌443133

以二元结构河岸崩塌模式为研究背景,在弯道水槽中展开系列试验,研究凹岸坡脚处成型崩塌体在水力作用下输移过程及其对岸坡稳定性与河床冲淤的交互影响。试验成果表明,崩塌体经水力分解破碎呈块状、片状或颗粒状起动,部分随水流带至凸岸... 详细信息

以二元结构河岸崩塌模式为研究背景,在弯道水槽中展开系列试验,研究凹岸坡脚处成型崩塌体在水力作用下输移过程及其对岸坡稳定性与河床冲淤的交互影响。试验成果表明,崩塌体经水力分解破碎呈块状、片状或颗粒状起动,部分随水流带至凸岸或下游,堆积在坡脚附近的崩塌体残留量随水力作用大小及土体特性不同而变化。崩塌体临水面周围尤其上下游端水流紊动强烈易形成较大剪切力区,临坡面上下游端附近剪切力较无崩塌体时减小;崩塌体体积越大,对剪切力区特征的改变也越明显。崩塌体的存在虽不能制止附近岸坡的再次崩塌,但可能抑制崩岸发展及附近河床淤积的程度,崩塌体的粘性或体积越大,这种抑制作用越显著;相同崩塌体抑制附近河床淤积的程度较抑制岸坡崩塌的程度大。

关键词：岸坡崩塌体水力输移河床演变水槽试验二元结构河岸