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Nano Research 2023年第11期16卷 12706-12712页

作者： yafei chen Zhengwei Pan Center for Integrative Petroleum Research College of Petroleum Engineering and GeosciencesKing Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia

We report the use of CaTiO_(3):Pr^(3+)multiband persistent luminescent nanoparticles,which can simultaneously emit red(610 nm),near-infrared(893 nm),and short-wave infrared(1040 nm)photoluminescence and persistent luminescence,as the tracer nanoagents for water tracer *** using a spectrofluorometer,an Si charge-coupled device(CCD)camera and an InGaAs array camera as the detection tools,we evaluated the sensing capabilities of the three emission bands of CaTiO_(3):Pr^(3+)nanoparticles in brine water solutions and crude oil/brine water emulsions in both photoluminescence mode and persistent luminescence *** these different detection combinations,the persistent luminescence-based Si CCD camera imaging exhibits the best sensing performance with the detection limits being at a single-digit ppb level for the 610 and 893 nm bands and about 100–200 ppb for the 1040 nm band in both water solutions and crude oil/water emulsions,while the photoluminescencebased Si CCD camera imaging has a much higher detection limit of~10 ppm in water solutions and of~200 ppm in oil/water *** persistent luminescence-based InGaAs array camera imaging to the 1040 nm band has the worst performance with the detection limits higher than 200 ppm for both *** sensing performances of the spectrofluorometer to photoluminescence signals and persistent luminescence signals in the two solutions are about the same,with the detection limits being around 100–200 ppm.

关键词： water tracer CaTiO_(3):Pr^(3+)nanoparticles photoluminescence persistent luminescence crude oil/water emulsion detection limit

Field-effect transistors with multiple channels constructed by carbon nanotubes

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Science China(Technological Sciences) 2005年第6期48卷 669-678页

作者： chen Changxin ZHANG yafei National Key Laboratory of Nano/Micro Fabrication Technology Key Laboratory for Thin Film and Microfabrication of Ministry of Education Institute of Micro and Nano Science and Technology Shanghai Jiaotong University Shanghai 200030 China National Key Laboratory of Nano/Micro Fabrication Technology Key Laboratory for Thin Film and Microfabrication of Ministry of Education Institute of Micro and Nano Science and Technology Shanghai Jiaotong University Shanghai 200030 China

Single-wall carbon nanotubes (SWNTs) pre-decorated with functional molecules are directly aligned in the AC electric field, which makes SWNTs parallelly bridge the source and drain electrodes and act as the multiple conduction channels of the field-effect transistor (FET). The method avoids the mutual tanglement of SWNTs and makes them align between the source and drain electrodes abreast and dispersedly. It is indicated that aligning SWNTs in the high-volatility solvents can decrease the contaminant around the electrodes and has a function to purify the raw SWNTs. The obtained multi-channel FET not only takes on a high transconductance, but also holds the good reliability and stability.

关键词： multi-channel, carbon nanotubes, field-effect transistors, directed alignment, transconductance.

Effect of Diatomite Additive on the Mechanical and Dielectric Properties of Porous SiO2-Si3N4 Composite Ceramics

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Journal of Wuhan University of Technology(Materials Science) 2016年第3期31卷 528-532页

作者：油光磊毕见强 chen yafei YIN Chonglong WANG Chang'an Key Laboratory for Liquid-Solid Structure Evolution and Processing of Materials Ministry of EducationShandong UniversityJinan 250061China School of Material Science and Engineering Shandong UniversityJinan 250061China State Key Laboratory of New Ceramic and Fine Processing Tsinghua UniversityBeijing 100084China

Porous SiO2-Si3N4 composite ceramics with high porosity and excellent mechanical properties were fabricated by pressureless-sintering at relatively low temperature of 1 500 ~C using diatomite as pore forming agent. The effects of diatomite on flexural strength, fracture toughness, shrinkage, porosity and phase transformation of the porous ceramics were investigated in detail. Compared with that of the ceramic without adding diatomite, the porosity of the ceramic with 10% diatomite is increased by about 27.4%, the flexural strength and fracture toughness reaches 78.04 MPa and 1.25 MPa.m1/2, respectively. As the porosity increases, the dielectric constant of porous SiO2-Si3N4 ceramic decreases obviously from 3.65 to 2.95.

关键词： silicon nitride diatomite porosity mechanical property dielectric constant

Assessing non-point source pollution in an apple-dominant basin and associated best fertilizer management based on SWAT modeling

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International Soil and Water Conservation Research 2023年第2期11卷 353-364页

作者： Yiwen Han Zhong Liu yafei chen Yingxuan Li Haipeng Liu Lianghong Song Yong chen College of Land Science and Technology China Agricultural UniversityBejing100193China Key Laboratory of Arable Land Conservation in North China Ministry of Agriculture and Rural AfairsBejing100193China Technology Innovation Center of Land Engineering Ministry of Natural ResourcesBeijing100037China Yantai Hydrology Bureau Yantai264009China

Investigating the impact of apple-dominated areas on nitrogen(N)and phosphorus(P)losses at a basin scale was essential for the sustainable development of apple industry in *** study conducted a survey on fertilizer application and built a Soil and Water Assessment Tool(SWAT)model to quantita-tively analyze the N and P losses in the Qixia apple-dominated ***,the decreases in N and P losses through adjusting the fertilizer application modes were *** showed that average N and P losses in the Wulong River Basin(WRB)were 44.4 and 0.365 kg ha^(-1)in 2011-2017,respectively,and apple orchards accounted for 733%and 51.4%of the total N and P losses in the *** nine fertilizer scheduling scenarios,three fertilizer schedule scenarios,automatic fertilizer application(S-AUTO),"one shot"mode(S1),and regulated fertilizer application(S-BSD),had the lowest N and P losses in apple *** decreases in N loss ranged from 20.6%to 26.1%at the subbasin scale and 14.8%-30.7%at the basin outlet when applying the S-AUTO,S1,and S-BSD fertilizer application modes in Qixia apple orchards and all apple orchards in the *** reductions in P loss varied from 22.0%to 46.1%at the subbasin scale and 14.6%-25.6%at the basin *** orchard-dominated basin,N and P losses can be effectively reduced by optimizing the orchard fertilizer scheduling strategies.

关键词： Apple orchards Questionnaire survey N and P losses Optimized fertilizer management Basin management

Viscosity profile prediction of a heavy crude oil during lifting in two deep artesian wells

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Chinese Journal of Chemical Engineering 2017年第7期25卷 976-982页

作者： Yibo Li Hao Gao Wanfen Pu Bing Wei yafei chen Dong Li Qiang Luo State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Research Institute of Experiment and Detection Xinjiang Oilfield CompanyPetroChina

It has been known that the productivity of artesian wells is strongly dependent on the rheological properties of crude oils. This work targets two deep artesian wells(>5000 m) that are producing heavy crude oil. The impacts of well conditions including temperature, pressure and shear rate, on the crude oil rheology were comprehensively investigated and correlated using several empirical rheological models. The experimental data indicate that this heavy oil is very sensitive to temperature as result of microstructure change caused by hydrogen bonding. The rheological behavior of the heavy oil is also significantly impacted by the imposed pressure, i.e., the viscosity flow activation energy(Eμ) gently increases with the increasing pressure. The viscosity–shear rate data are well fitted to the power law model at low temperature. However, due to the transition of fluid feature at high temperature(Newtonian fluid), the measured viscosity was found to slightly deviate from the fitting data. Combining the evaluated correlations, the viscosity profile of the heavy crude oil in these two deep artesian wells as a function of well depth was predicted using the oilfield producing data.

关键词： Heavy oil Rheological properties Empirical correlation Viscosity profile predication Lifting process Artesian well

A model for thermal annealing on forming In—N clusters in InGaNP

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Science China(Physics,Mechanics & Astronomy) 2012年第5期55卷 798-801页

作者： ZHAO ChuanZhen chen Lei LI NaNa ZHANG HuanHuan chen yafei WEI Tong TANG ChunXiao XIE ZiLi School of Electronics and Information Engineering Tianjin Polytechnics UniversityTianjin 300160China School of Textiles Tianjin Polytechnic UniversityTianfin 300160China Key Laboratory of Advanced Textile Composites Ministry of Education of ChinaTianjin 300160China College of Science Civil Aviation University of ChinaTianjin 300300China Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials Department of Electronic Science and EngineeringNanjing UniversityNanjing 210093China

We develop a model for the effect of thermal annealing on forming In--N dusters in GalnNP according to thermodynamics. The average energy variation for forming an In--N bond in the model is estimated according to the theoretical calculation. Using the model, the added number of In--N bonds per mol of InGaNP, the added number of nearest-neighbor In atoms per N atom and the average number of nearest-neighbor In atoms per N atom after annealing are calculated. The different function of In--N clusters in InGaNP and InGaN is also discussed, which is due to the different environments around the In--N clusters.

关键词： InGaNP annealing In--N clusters thermodynamics

1-((12-Bromododecyl)oxy)-4-((4-(4-pentylcyclohexyl)phenyl)ethynyl) benzene: Liquid crystal with aggregation-induced emission characteristics

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Science China Chemistry 2013年第9期56卷 1191-1196页

作者： chen yafei LIN JieSheng YUAN WangZhang YU ZhenQiang LAM Jacky WingYip TANG Ben Zhong Shenzhen Key Laboratory of Functional Polymers School of Chemistry and Chemical EngineeringShenzhen University National Institutes for Food and Drug Control School of Chemistry and Chemical engineering Shanghai Jiao Tong University Department of Chemistry The Hong Kong University of Science & Technology

The luminescent liquid crystals (LLCs) are expected to solve the conflicts between the aggregation caused quenching and the requirement of aggregation or self-organization for LCs. Herein, we developed a new strategy of applying aggregation-induced emission (AIE) phenomenon to the molecular design of LCs towards LLCs. In this report, a calamitic liquid crystal based on tolane with AIE characteristics was successfully synthesized and the chemical structure was characterized by 1H, 13C NMR, and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) high-resolution mass spectra. The fluorescence behavior was studied by fluorescence spectroscopy and the liquid crystal phase behaviors were investigated by differential scanning calorimetry (DSC), polarized optical microscopy (POM). The crystal structure was obtained by X-ray diffraction crystallography with P1 space group. Results demonstrated that the sample was AIE active and the LC phases sequence during cooling was nematic, smectic C and smectic B phase.

关键词： aggregation-induced emission tolane liquid crystal phase behavior

Downregulation of ceramide synthase 1 promotes oral cancer through endoplasmic reticulum stress

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International Journal of Oral Science 2021年第1期13卷 108-116页

作者： Wen chen chenzhou Wu yafei chen Yuhao Guo Ling Qiu Zhe Liu Haibin Sun Siyu chen Zijian An Zhuoyuan Zhang Yi Li Longjiang Li State Key Laboratory of Oral Diseases&National Clinical Research Center for Oral Diseases&Department of Head and Neck Oncology West China Hospital of StomatologySichuan UniversityChengduChina Department of Oral and Maxillofacial-Head and Neck Oncology Capital Medical University School of StomatologyBeijingChina

C18 ceramide plays an important role in the occurrence and development of oral squamous cell ***,the function of ceramide synthase 1,a key enzyme in C18 ceramide synthesis,in oral squamous cell carcinoma is still *** aim of our study was to investigate the relationship between ceramide synthase 1 and oral *** this study,we found that the expression of ceramide synthase 1 was downregulated in oral cancer tissues and cell *** a mouse oral squamous cell carcinoma model induced by 4-nitroquinolin-1-oxide,ceramide synthase 1 knockout was associated with the severity of oral malignant *** studies showed significant upregulation of PCNA,MMP2,MMP9,and BCL2 expression and downregulation of BAX expression in the pathological hyperplastic *** addition,ceramide synthase 1 knockdown promoted cell proliferation,migration,and invasion in *** of CERS1 obtained the opposite *** synthase 1 knockdown caused endoplasmic reticulum stress and induced the VEGFA *** transcription factor 4 is responsible for ceramide synthase 1 knockdown caused VEGFA transcriptional *** addition,mild endoplasmic reticulum stress caused by ceramide synthase 1 knockdown could induce cisplatin *** together,our study suggests that ceramide synthase 1 is downregulated in oral cancer and promotes the aggressiveness of oral squamous cell carcinoma and chemotherapeutic drug resistance.

关键词： endoplasmic cancer reticulum

An Innovative Study on the Path of Integrating Curriculum Ideology and Politics in College English Teaching:Taking An Overview of Chinese Culture as an Example

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Journal of Contemporary Educational Research 2023年第12期7卷 226-231页

作者： Xin Zuo yafei chen School of International Business Qingdao Huanghai UniversityQingdao 266555Shandong ProvinceChina

With the rapid development of information technology and the Internet,people can easily and quickly obtain news and information from all over the *** the state’s requirements for the curriculum ideology and politics are being strengthened,it is necessary to adapt to the needs of the times and integrate ideology and politics into college English *** of ideology and politics into teaching is a challenge faced by colleges and universities nowadays,which aims to make ideology and politics alive and well and more acceptable to contemporary college *** view of this,this paper starts with the importance of the integration of ideology and politics into college English teaching,takes An Overview of Chinese Culture as an example,analyzes new approaches for integrating ideology and politics into the teaching process,and formulates the teaching design centered around these approaches,so as to promote the organic integration of ideology and politics with English teaching.

关键词： College English Curriculum ideology and politics English teaching Teaching innovation

A smartphone-based automated fluorescence analysis system for point-of-care testing of Hg(Ⅱ)

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Journal of Innovative Optical Health Sciences 2022年第5期15卷 28-40页

作者： yafei chen Ke Zhang Yuan Liu Chunsun Zhang MOE Key Laboratory of Laser Life Science&Institute of Laser Life Science College of Biophotonics South China Normal University Guangzhou 510631 P.R.China

This work demonstrates a smartphone-based automated fluorescence analysis system(SAFAS)for point-of-care testing(POCT)of Hg(Ⅱ).This system consists of three *** smartphone module is used to provide an excitation light source,and to collect and analyze fluorescent *** dark box module is applied to integrate the desired optical elements and offers a dark *** cost of the integrated dark box mainly includes the upper cover,box body,lower bottom,¯xture and some optical elements which is about$*** chip module is used for fluorescence sensing,which is composed of an upper plate,bottom plate and cloth-based *** to the integration of multiple smartphone functions,the SAFAS eliminates the need for additional power sources,light sources and analysis *** dark box and upper and bottom plates are made by 3D *** cloth-based chip(about$0.005 for each chip)is fabricated using the wax screenprinting technique,with no need for expensive and complex fabrication *** our knowledge,the cloth-based microfluidic fluorescence detection method combined with smartphone functions is first *** using optimal conditions,the designed system can realize the quantitative detection of Hg(Ⅱ),which has a linear range of 0.001–100μgmL^(-1)and a detection limit of 0.5 ngmL^(-1).Additionally,the SAFAS has been successfully applied for detecting Hg(Ⅱ)in actual water samples,with recoveries of 100.1%–111%,RSDs of 3.88%–9.74%,and fast detection time of about 1 ***,the proposed SAFAS has the advantages of high sensitivity,wide dynamic range,acceptable reproducibility,good stability and low ***,it is believed that the presented SAFAS has great potential to perform the POCT of Hg(II)in different water samples.

关键词： Smartphone automated fluorescence detection cloth-based chip point-of-care testing Hg(II).