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Microscopic and Fractal Characterization of Organic Matter within Lacustrine Shale Reservoirs in the First Member of Cretaceous Qingshankou Formation,Songliao Basin,Northeast China

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Journal of Earth Science 2020年第6期31卷 1241-1250页

作者： Bo Liu Meng Yan Xianda Sun yunfeng bai Longhui bai Xiaofei Fu Key Laboratory of Continental Shale Hydrocarbon Accumulation and Efficient Development Ministry of EducationNortheast Petroleum UniversityDaqing 163711China State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of TechnologyChengdu 610051China PetroChina Daqing Oilfield Company Daqing 163318China

Understanding the occurrences of different fractions of organic matter in shale reservoirs is very important for the evaluation of shale *** organic-rich shale samples from the first member of the Cretaceous Qingshankou Formation in the Songliao Basin were analyzed with confocal laser scanning microscopy(CLSM)and fluorescence spectral *** results show that the occurrences of different organic components are related to the fabric of samples and vary with *** bulk content of light components is significantly higher than heavy components and exhibits a positive relationship with quartz and feldspar *** light and heavy components are distributed parallel with the lamination in microscopic view in laminated samples,and randomly in massive *** maximum radius of light components in most of the samples is larger than 20μm,while it is smaller for heavy components,indicating the micro fractionation from clay/organic lamina to quartz/feldspar *** depth of enrichment of light components corresponds to the oil maturity of organic *** the distribution of light and heavy components fits the same fractal model,with fractal dimensions ranging between 2.2 and *** CLSM results confirm that it can be a reliable tool for the"sweet spot"exploration.

关键词： confocal laser scanning fractal bitumen lithofacies shale oil

A Novel Coumarin-based Fluorescence Chemosensor for Fe^3＋

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Chemical Research in Chinese Universities 2014年第4期30卷 560-565页

作者： WANG Ruiping WAN Qihua FENG Feng bai yunfeng Department of Chemistry College of Sciences Nanchang University Nanchang 330047 P. R. China Department of Chemistry Datong University Datong 037009 P. R. China

A novel coumarin derivative[7-diethylamino-2-oxo-2H-chromene-3-carboxylic acid（6-amino-pyridin2-yl）-amide,CFe1] has been synthesized and its potential application as a chemosensor for the detection of metal ions has been further *** responses of CFe1 to Fe^3＋ were studied by fluorescence emission spectrometry in the presence of other metal ions such as Al^3＋,Ba^2＋,Ca^2＋,Co^3＋,Cr^3＋,Cu^2＋,Fe^2＋,Hg^2＋,Mg^2＋,Mn^2＋,Na^＋,Ni^＋,Pb^2＋,Zn^2＋,K^＋,and Ag^＋.CFe1 showed a good selectivity for Fe^3＋ with fast response,a wide pH span of 3.3-9.18,and a large Stocks ***1 in the presence of Fe^3＋ and ethylene diamine tetraacetic acid（EDTA） makes the blue solution fade to colorless,which is due to the formation of CFe1-Fe^3＋ complex instead of any catalytic action of Fe^3＋.Furthermore,the imaging of Fe^3＋ in cultured single mice microglia cells was realized with the aid of CFe1,indicating that CFe1 has a great potential to be used as promising models for the future design of novel and robust chemosensor for metal ion detection in the field of biomedical and environmental analyses.

关键词： Coumarin Fe3+ Fluorescence Selectivity

Suppression of inner energy dissipation in Yb-doped NaErF_(4)upconversion nanocrystals through an energy cycling strategy

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Journal of Rare Earths 2023年第7期41卷 975-980,I0001页

作者： yunfeng bai Xiaoxi Liu Shaojian Zhang Haili Jiang Lu Liu Isam Ud Din Jianzhong Zhang Key Laboratory of Micro Nano Optoelectronic Devices and Intelligent Perception Systems School of Electronic Information and EngineeringYangtze Normal UniversityChongqing 408100China College of Physics and Optoelectronic Engineering Harbin Engineering UniversityHarbin 150001China

Suppression of the inner energy dissipation,related to the lattice phonons and inner defects,in lanthanide doped upco nversion luminescent materials remains a formidable ***,we reveal an energy cycling strategy capable of suppressing the inner energy dissipation in lanthanide doped upconversion ***^(3+)ions were introduced in Er^(3+)heavily doped nanocrystals as an energy reservoir to compete with the inner energy *** detailed energy cycling processes between Er^(3+)activator and Yb^(3+)reservoir,responsible for the enhancement of Er^(3+)upconversion intensity,are proposed and further verified on the basis of spectral *** energy cycling strategy,with unique merits like facile and cost-effective preparation as well as broad scope of application,is highly valuable in lanthanide luminescent nano materials.

关键词： Upconversion Er^(3+) 1530 nm excitation Inner energy dissipation Energy cycling Rare earths

Explorations in Teaching Research by a Tutoring Institution in China

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ECNU Review of Education 2019年第1期2卷 87-94页

作者： yunfeng bai Xueli Tang Xingfang Li Shunan Fan TAL Education Group China The University of Hong Kong China East China Normal University China

Purpose:This article focuses on rarely explored organizational practice of teaching research in China’s private tutoring *** a large private tutoring institution as an example,the article examines how private tutoring institutions understand and engage in educational explorations of standardization and informatization ***/Approach/Methods:The article is based on a case study of one of the biggest tutoring companies in *** study started with document analysis of the institutional history,supplemented by interviews with personnel who have worked in the institution since it was ***,the researchers collected empirical data using mixed *** data were obtained from the user database owned by the *** data were collected directly by the researchers through interviews and participant *** qualitative and quantitative data were analyzed from multiple ***:Teaching research in private tutoring institutions commonly differs from that in public *** this particular case,it is technology-driven,student-tailored,and *** well,it can supplement the mainstream public education system and promote education innovation and equity throughout the ***/Value:It is hoped that this article could give some insights into the possibility of the cooperation between formal schools and tutoring institutions in the areas of teaching research and other in-class and off-campus *** article can also draw public attention to the necessity and benefits of adopting technical methods in the teaching process.

关键词： China educational informatization private tutoring teaching research teaching standardization

Numerical analysis of electromagnetic force field through the use of two examples

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Baosteel Technical Research 2013年第3期7卷 50-56页

作者： bai yunfeng Special Steel R & D Center Research InstituteBaoshan Iron & Steel Co.Ltd

In modern processing of conducting materials, such as steel,the time-varying electromagnetic field plays a key role in obtaining the desired microstructure or eliminating solidification defects such as porosity and segregation in cast billets. Up to now,few studies on the induced electromagnetic force （also called the Lorentz force） field in liquid metal have been reported. Compared with the magnetic field, the induced force field is the real and only direct cause for flow control. The electromagnetic force is comprised of two components. One is time-independent and the other is time- dependent. The time-dependent component varies with time in both amplitude and direction. When it reaches the extreme value,it can be one dozen times larger than the time-independent component. In this paper, a new method to quantitatively describe the induced electromagnetic force in liquid metal under a harmonic electromagnetic field,including both its time- independent and dependent components, was proposed based on the formula derivation from the data of amplitude and phase angle. Through this method ,the features of the time-dependent component were discussed, including the directions of rotation and the long axis. As a result, the force pattern was described. With two example calculations, the method was explained in detail. The results of both examples show that the force field in liquid metal can be divided into several regions with different force features. Example 1 shows the effect of coil position on the evolution of the force field pattern in liquid metal. Example 2 is a kind of stirring by the travelling magnetic field ,whose results present the sub-structures in metal and show that most of them have almost the same rotating direction.

关键词： electromagnetic force field numerical analysis time-dependent component quantitative description sub-structure in force field

Influences of liners and magnetic flux concentrator on induced Joule heat in hot extruded billet

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Baosteel Technical Research 2012年第2期6卷 44-48页

作者： bai yunfeng Special Steel Techndogy Center Research Institute. Baoshan Iron ＆ Steel Co. Ltd. Shanghai 200940 China

In the production of pipes by hot extrusion method,billets should be heated to a certain temperature before hot extrusion by induction heating. The segmented liners in the induction furnace can possibly affect the circumferential Joule heat generation,thus leading to an uneven temperature field. The commonly used magnetic flux concentrators （MFC） can increase the temperature on both ends of the billet. In this paper ,the possible effect of liners and the factors affecting the utilization of the MFC,including the permeability,dimension and position,are all numerically studied and determined.

关键词： hot extruded billet induction heating circumferential liners MFC Joule heat generation

Effectiveness and safety of Chinese herbal medicines for hepatitis B virus-related acute-on-chronic liver failure:study protocol for a multicenter randomized controlled trial

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Journal of Traditional Chinese Medicine 2020年第6期40卷 1052-1059页

作者： Zhang Ning Zhou Chao Wang Lifu He Tingting Wang Yao Wang Yan bai yunfeng Li Jun Xiao Xiaohe Gong Man Integrated Traditional Chinese Medicine&Western Medicine Department the Fifth Medical CenterGeneral Hospital of PLABeijing 100039China

OBJECTIVE:To conduct a multicenter randomized controlled trial of the efficacy of standardized Chinese herbal medicines(CHMs)against acuteon-chronic liver failure(ACLF)and provide reproducible and high-level evidence for clinical ***:This is a prospective,multicenter,centrally randomized controlled *** diagnosed with hepatitis B virus-related ACLF(n=510)will be allocated to the standard medical therapy or CHM group at a 1∶1 *** CHMs will be used on the basis of the traditional Chinese medicine syndrome:Liangxue Jiedu granules for excess syndromes and Yiqi Jiedu granules for deficiency *** primary outcome is transplant-free survival at week *** secondary outcomes are(a)transplant-free survival at week 24,(b)liver function as assessed using the model for end-stage liver disease score at week 12,(c)liver function as assessed using the Child-Pugh score at week 12,and(d)the incidence of complications at week ***:The effectiveness and safety of CHM formulations will be assessed following treatment for *** REGISTRATION:The trial was registered at Clinical ***(NCT03577938)on June 24,2018.

关键词： Acute-on-chronic liver failure Hepatitis B chronic Drugs Chinese herbal Randomized controlled trial Clinical protocols

Generation of double-virus-resistant marker-free transgenic potato plants

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Progress in Natural Science:Materials International 2009年第5期19卷 543-548页

作者： yunfeng bai, Zhihua Guo, Xiaoqi Wang, Dongmei bai, Weifeng Zhang Institute of Crop Genetics, Shanxi Academy of Agricultural Sciences, Nongke Beilu No. 16, Taiyuan 030031, China [a]Institute of Crop Genetics Shanxi Academy of Agricultural Sciences Nongke Beilu No. 16 Taiyuan 030031 China

Viruses are very widespread in nature, and they cause severe diseases and yield losses in potato production. The transfer of the dsRNA-producing gene could confer a high level virus resistance by specific targeting of cognate viral RNA. In this study, we constructed a marker-free expression vector of a chimeric gene derived from the coat protein sequence of Potato virus X (PVX) and the nuclear inclusion protein sequence of Potato virus Y (PVY) in the form of an intramolecular dsRNA. Then this chimeric gene was introduced into potato cv. Zihuabai, a popular variety in China, via Agrobacterium tumefaciens-mediated transformation. Marker gene-free transgenic plants resistant to both PVX and PVY were obtained and confirmed by RT-PCR and DAS-ELISA detection. Northern blot analysis showed that transgene-derived mRNA was cleaved into short interfering RNAs (siRNAs), and that the virus resistance was mediated by RNA silencing. One important aspect of the study is that the transgenic viral sequence is not translated and the actual RNA transcript is cleaved, which possibly limit the environmental risks, such as transcapsidation and recombination of the transgene with an incoming virus. In addition, the biosafety risk resulting from marker genes can be avoided because of the absence of marker genes in transgenic plants.

关键词： Solanum tuberosum Marker-free RNA silencing Double-virus resistance Transgene

Conversion of induction heating temperature from ANSYS to DEFORM

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Baosteel Technical Research 2011年第4期5卷 8-11页

作者： bai yunfeng JIANG Hong Special Steel Technology Center Research Institute Baoshan Iron ＆ Steel Co. Ltd. Shanghai 200940 China School of Materials Science and Engineering Shanghai Jiaotong University Shanghai 200240 China

In the production of hot extrusion pipes, the billet will be heated in an induction furnace, before piercing or extrusion,to a certain temperature. The induction heating temperature field profile in the billet will exert an influence on the deformation processes. The study has developed an data conversion program to convert the temperature data from induction heating by ANSYS to deformation simulation software DEFORM; therefore, not only the relatively accurate temperature field can be made available, compared with the usually assumed uniform temperature field, but also the connection between induction heating and deformation can be established, which is essential to evaluate the processing parameters. Numerical simulation of the piercing processes of different temperature fields by induction heating was carded out, and the results have shown that the different initial temperature fields in the billet can lead to different deformation curves, which indicates that the conversion program is necessary to study the production process of hot extrusion pipes.

关键词： induction heating numerical simulation data conversion billet piercing