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Experimental study on dynamic mechanism of vortex evolution in a turbulent boundary layer of low Reynolds number

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Journal of Hydrodynamics 2020年第5期32卷 807-819页

作者： Yan-ang Guo Xiang-rui Dong Xiao-shu Cai Wu zhou School of Energy and Power Engineering University of Shanghai for Science and TechnologyShanghai 200093China Key Laboratory of Multiphase Flow and Heat Transfer in Shanghai Power Engineering Shanghai 200093China

The dynamic mechanism of the vortex generation and evolution process in a fully developed turbulent boundary layer with Reθ=97-194 is experimentally *** this study,a moving single-frame and long-exposure(MSFLE)imaging method and a moving particle image velocimetry/particle tracing velocimetry(M-PIV/PTV)are designed and implemented for measuring the temporal and spatial evolution of vortex cores in both qualitative and quantitative ways,*** the other hand,the Liutex vector,which is a new mathematical definition and identification of the vortex core proposed by Liu’s group,is first applied in the experiment for the structural visualization and quantitative analysis of the local fluid *** results show that an intuitional process of vortex evolution can be clearly observed by tracking the vortex using MSFLE and verify that the roll-up of the shear layer induced by shear instability is the origin of vortex formation in ***,a quantitative investigation in terms of the critical vortex core boundary(size)and its accurate rotation strength is carried out based on the Liutex vector field analysis by M-PIV/*** to statistics of the relation between vortex core size and the rotation strength during the whole process,the physical mechanism of vortex generation and evolution in a turbulent boundary layer of low Reynolds number can be summarized as a four-dominant-state course consisting of the“synchronous linear segment(SL)-absolute enhancement segment(AE)-absolute diffusion segment(AD)-skewing dissipation segment(SD)”.

关键词： Turbulent boundary layer high-and low-speed fluid vortex generation moving single-frame and long-exposure moving particle image velocimetry/particle tracing velocimetry Liutex vector

Immobilization of Bovine Serum Albumin on Poly(ether ether ketone) for Surface Biocompatibility Improvement

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Chemical Research in Chinese Universities 2012年第2期28卷 353-357页

作者： SUN Hui CHEN rui-chao LI ang XU Guo-zhi School of Materials Science and Mechanical Engineering Beijing Technology and Business UniversityBeijing 100048P R.China

UV-induced graft polymerization of acrylic acid（AA） on poly（ether ether ketone）（PEEK） films was carried out to introduce ―COOH for the subsequent immobilization of bovine serum albumin（BSA）.BSA was introduced on PEEK surface based on the condensation reaction between ―NH 2 and ―*** modified surface（PEEK-BSA） was characterized by energy-disperse spectrometry（EDS）,X-ray photoelectron spectroscopy（XPS）,water contact angle measurement and UV spectrum *** contact angle was found to decrease from 104° for the virgin PEEK films to 63° for the BSA-immobilized PEEK films,demonstrating a significant improvement of surface ***,the appearance of nitrogen on PEEK film confirmed by XPS and EDS indicates the immobilization of BSA on PEEK surface.

关键词： Poly(ether ether ketone)(PEEK) UV-grafting Bovine serum albumin immobilization

Cobalt nanoparticle decorated N-doped carbons derived from a cobalt covalent organic framework for oxygen electrochemistry

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Frontiers of Chemical Science and Engineering 2021年第6期15卷 1550-1560页

作者： rui-Qi z.ang ang Ma Xiang Liang Li-Min zhao Hui zhao zhong-Yong Yuan School of Materials Science and Engineering Liaocheng UniversityLiaocheng252000China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) School of Materials Science and EngineeringNankai UniversityTianjin3000350China

The low cost and highly efficient construction of electrocatalysts has attracted significant attention owing to the use of clean and sustainable energy *** this work,cobalt nanoparticle decorated N-doped carbons(Co@NC)are synthesized by the pyrolysis of a cobalt covalent organic framework under an inert *** Co@NC demonstrates improved electrocatalytic capabilities compared to N-doped carbon without the addition of Co nanoparticles,indicating the important role of *** well-dispersed active sites(Co-Nx)and the synergistic effect between the carbon matrix and Co nanoparticles greatly enhance the electrocatalytic activity for the oxygen reduction *** addition,the Co content has a significant effect on the catalytic *** resulting Co@NC-0.86 exhibits a superb electrocatalytic activity for the oxygen reduction reaction in an alkaline electrolyte in terms of the onset potential(0.90 V),half-wave potential(0.80 V)and the limiting current density(4.84 mA·cm^(−2)),and a high selectivity,as well as a strong methanol tolerance and superior durability,these results are comparable to those of the Pt/C ***,the superior bifunctional activity of Co@NC-0.86 was also confirmed in a home-built zn-air battery,signifying the possibility for application in electrode materials and in current energy conversion and storage devices.

关键词： cobalt embedment N-doped carbons covalent organic framework oxygen reduction zn-air battery

Enhanced detection of ppb-level NO_(2)by uniform Pt-doped znSnO_(3)nanocubes

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International Journal of Minerals,Metallurgy and Materials 2022年第6期29卷 1295-1303页

作者： Yaoyu Yin Yanbai Shen Sikai zhao ang Li rui Lu Cong Han Baoyu Cui Dezhou Wei School of Resources and Civil Engineering Northeastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110189China

znSnO_(3) nanocubes(zSNCs)with various Pt concentrations(i.e.,1 at%,2 at%,and 5 at%)were synthesized by a simple one-pot hydrothermal *** microstructures of pure and Pt-doped zSNCs were characterized by X-ray diffractometry,scanning electron microscopy,transmission electron microscopy,energy-dispersive X-ray spectroscopy,and X-ray photoelectron *** showed that the pure zSNCs have a perovskite structure with a side length of approximately 600 nm;this length was reduced to 400 nm after Pt *** doping,PtO_(x)(PtO and PtO_(2)) nanoparticles with a diameter of approximately 5 nm were uniformly coated on the surface of the *** investigation of the gas-sensing abilities of the nanocubes showed that the Pt-doped zSNCs have excellent sensing properties toward nitrogen dioxide(NO_(2)) gas in the operating temperature range of 75-175℃.Among the sensors prepared,that based on 1 at%Pt-doped zSNCs exhibited the best response of 16.0 toward 500 ppb NO_(2) at 125℃;this response is over 11 times higher compared with that of pure *** enhanced NO_(2) sensing mechanism of the Pt-doped zSNCs may be attributed to the synergistic effects of catalytic activity and chemical sensitization by Pt doping.

关键词： znSnO_(3)nanocubes Pt doping nitrogen dioxide gas sensor

Characterization and biodegradation kinetics of a new cold-adapted carbamazepine-degrading bacterium, Pseudomonas sp. CBz-4

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Journal of Environmental Sciences 2013年第11期25卷 2281-2290页

作者： ang Li rui Cai Di Cui Tian Qiu Changlong Pang Jixian Yang Fang Ma Nanqi Ren State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology National Supervision and Inspection Center of Environmental Protection Equipment Quality Yixing Urban Supervision andInspection Administration of Product Quality

Carbamazepine is frequently detected in waters and hardly eliminated during conventional wastewater treatment processes due to its complicated chemical structure and resistance to biodegradation. A carbamazepine-degrading bacterium named CBz-4 was isolated at a low temperature （10℃） from activated sludge in a municipal wastewater treatment plant. Strain CBz-4, which can use carbamazepine as its sole source of carbon and energy, was identified as Pseudomonas sp. by the 16S rRNA gene sequence. The composition and percentage of fatty acids, which can reveal the cold-adaptation mechanism of strain CBz-4, were determined. Strain CBz-4 can effectively degrade carbamazepine at optimal conditions： pH 7.0, 10℃, 150 r/min rotation speed, and 13% inoculation volume. The average removal rate of carbamazepine was 46.6% after 144 hr of incubation. The biodegradation kinetics of carbamazepine by CBz-4 was fitted via the Monod model. Vmax and Ks were found to be 0.0094 hr^-1 and 32.5 mg/L, respectively.

关键词： carbamazepine low temperatures biodegradation kinetics Pseudomonas sp.

Enhanced Electron Transfer Ability via Coordination in Block Copolymer/Porphyrin/Fullerene Micelle

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Chinese Journal of Polymer Science 2017年第11期35卷 1328-1341页

作者： Ruo-lin Wang rui Qu Yan zhai Chen Jing ang Li Ying-li An 史林启 State Key Laboratory of Medicinal Chemical Biology Key Laboratory of Functional Polymer MaterialsMinistry of Education Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)Institute of Polymer Chemistry Nankai University

Inspired by structures of antenna-reaction centers in photosynthesis, the complex micelle was prepared from zinc tetra-phenyl porphyrin （znTPP）, fullerene derivative （PyC60） and poly（ethylene glycol）-block-poly（E-caprolactone）（PEG-b- PCL）. The core-shell structure made the hydrophobic donor-acceptor system work in aqueous. In micellar core, coordination interaction occurred between znTPP and PyC60 molecules which ensured the enhanced energy migration from the donor to the acceptor. The enhanced interaction between porphyrin and fullerene was confirmed by absorption, steady-state fluorescence and transient fluorescence. The generation of singlet oxygen and superoxide radical was detected by iodide method and reduction of nitro blue tetrazolium, respectively, which confirmed that electron transfer reaction in the complex micellar core occurred. Moreover, the complex micelle exhibited effective electron transfer performance in photodebromination of 2,3-dibromo-3-phenylpropionic acid. The complex micellar structure endowed the donor-acceptor system with improved stability under irradiation. This strategy could be helpful for designing new electron transfer platform and artificial photosynthetic system.

关键词： Porphyrin Fullerene Micelle Coordination Electron transfer

X-ray excited Mn^(2+)-doped persistent luminescence materials with biological window emission for in vivo bioimaging

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Journal of Rare Earths 2024年第1期42卷 28-35,I0001页

作者： Hanrun zheng Lin Liu Yi’ang Li rui Rong Liang Song Junpeng Shi Jing Teng Xia Sun Yun z.ang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China University of the Chinese Academy of Sciences Beijing100049China Xiamen Hospital of Traditional Chinese Medicine Xiamen361015China Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou350108China

In recent years,persistent luminescence materials(PLMs)excited by X-rays and emitting in biological windows have received extensive attention in the field of high-sensitivity *** metal Mn^(2+)is an ideal emission center,but few studies focus on Mn^(2+)-doped PLMs with X-ray excitation and biological window ***,we report a Mn^(2+)-doped PLM,LiYGeO_(4):Mn^(2+)(LYGM),with excellent biological window persistent luminescence *** excitation by UV,LYGM produces a durable biological window of persistent luminescence emission at 660 nm for up to 20 *** *** can be repeatedly excited by X-rays,resulting in long-term biological window persistent luminescence *** addition,we obtain LYGM around 200 nm in diameter by ball milling and centrifugation and improve its biocompatibility by surface modification to apply it to in vivo imaging in *** LYGM are injected into mice through the tail vein,in situ excitation of X-rays can be *** the persistent luminescence decays,LYGM can be re-excited for repeated ***,LYGM shows potential prospects for in vivo deep tissue and long-term bioimaging.

关键词： Persistent luminescence X-ray Biological window In vivo imaging Rare earths

Carbon‐based materials for all‐solid‐state zinc–air batteries

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Carbon Energy 2021年第1期3卷 50-65页

作者： Dan Yang Dong Chen Yu Jiang Edison Huixiang ang Yuezhan Feng Xianhong rui Yan Yu School of Materials and Energy Guangdong University of TechnologyGuangzhouChina Hefei National Laboratory for Physical Sciences at the Microscale Key Laboratory of Materials for Energy ConversionChinese Academy of Sciences(CAS)University of Science and Technology of ChinaHefeiAnhuiChina Natural Sciences and Science Education National Institute of EducationNanyang Technological UniversitySingaporeSingapore Key Laboratory of Materials Processing and Mold(zhengzhou University) Ministry of EducationZhengzhou UniversityZhengzhouChina Dalian National Laboratory for Clean Energy(DNL) Chinese Academy of SciencesDalianLiaoningChina State Key Laboratory of Fire Science University of Science and Technology of ChinaHefeiAnhuiChina

Solid‐state zn–air batteries(zABs)hold great potential for application in wearable and flexible ***,further commercialization of current zABs is still limited by the poor stability and low energy *** is,thus,crucial to develop efficient catalysts as well as optimize the solid electrolyte system to unveil potential of the zAB *** to the low cost and versatility in tailoring the structures and properties,carbon materials have been extensively used as the conductive substrates,catalytic air electrodes,and important components in the electrolytes for the solid‐state *** this context,we discuss the challenges facing current solid‐state zABs and summarize the strategies developed to modify properties of carbon‐based electrodes and *** highlight the metal−organic framework/covalent organic framework‐based electrodes,heteroatom‐doped carbon,and the composites formed of carbon with metal oxides/sulfides/*** also briefly discuss the progress of graphene oxide‐based solid electrolyte.

关键词： carbon material heteroatom‐doped carbon solid electrolyte solid‐state zn–air battery

Single-nucleotide polymorphisms,mapping and association analysis of 1-FFT-A1 gene in wheat

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Journal of Integrative Agriculture 2017年第4期16卷 789-799页

作者： YUE Ai-qin LI ang MAO Xin-guo CHang Xiao-ping LI Run-zhi JING rui-lian College of Agriculture Shanxi Agricultural University Institute of Crop Sciences Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Germplasm and UtilizationMinistry of Agriculture

Fructans are major nonstructural carbohydrates in wheat （Triticum aestivum L.）. Fructan 1-fructosyltransferase （1-FFT） is the key enzyme in fructan biosynthesis. In the present study, 96 sequence variants were detected in the 1-FFT-A 1 gene among 26 wheat accessions including UR208, and 15 of them result in amino acid substitutions, forming four haplotypes. Two markers M39 and M2164 were developed based on the InDe121-39 and SNP-2164 polymorphisms to distinguish the three haplotypes in the 1-FFT-AI. 1-FFT-A1 was located on chromosome 4A using marker M2164 and was flanked by markers Xcwm27 and 6-SFT-A 1. By association analysis using a natural wheat population consisted of 154 accessions, the results showed that the two markers were significantly associated with water-soluble carbohydrate （WSC） content in the lower internode stem and total stem at the early and middle grain filling stages, 1 000-grain weight （TGW） at different grain filling stages and peduncle length （PLE）. Comparison of the effects of three haplotypes on agronomic traits indicated that TGW, PLE and total number of spikelets per spike （TNSS）were significantly influenced by haplotypes. Haplll showed a significant positive effect on TGW, PLE and TNSS.

关键词： 1-FFT-A1 single nucleotide polymorphism association analysis haplotype marker development wheat