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Transferring CdTe Nanoparticles from Liquid Phase to Polyvinylpyrrolidone Nanofibers by Electrospinning and Detecting Its Photoluminescence Property

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Chemical Research in Chinese Universities 2008年第4期24卷 459-463页

作者： WANG Shu-gang yang qing-biao BAI Jie SONG Yan ZHANG Chao-qun LI Yao-xian Department of Organic Chemistry College of Chemistry Jilin University Changchun 130021 P R. China

The major aim of this work was to synthesize thio-stabilized CdTe nanoparticles（NPs） in an aqueous solution, which was then enwrapped with cetyltrimethylammonium bromide（CTAB）, and finally transferred to the polyvinylpyrrolidone（PVP） matrix by electrospinning. The PVP nanofibers containing CdTe NPs were characterized by scanning electron microscopy（SEM） and transmission electron microscopy（TEM）, to observe the morphology of the nanofibers and the distribution of CdTe NPs. The selective area electronic diffraction（SAED） pattern verified that CdTe NPs were cubic lattice. The photoluminescence（PL） spectrum indicated that CdTe NPs existed in an optical style in PVP nanofibers. Moreover, X-ray photoelectron spectra（XPS） revealed that thiol-stabilized CdTe NPs were enwrapped by CTAB, and PVP acted as a dispersant in the process of electrospinning.

关键词： CTAB Electrospinning Nanofiber Nanoparticle Photoluminescence

Facile Method to Prepare Metal Sulfide(Ag_2S,CuS,PbS) Nanoparticles Grown on Surface of Polyacrylonitrile Nanofibre and Their Optical Properties

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Chemical Research in Chinese Universities 2012年第3期28卷 534-538页

作者： ZHANG Chao-qun SUN Jiao WANG Wei yang qing-biao LI Yao-xian DU Jian-shi China-Japan Union Hospital of Jilin University Changchun 130031P.R.China College of Chemistry Jilin UniversityChangchun 130012P.R.China School of Nursing Jilin UniversityChangchun 130031P.R.China

Polyacrylonitrile-metal sulfide nanocomposites with metal sulfide（Ag2S, CuS, PbS） nanoparticles homo- geneously dispersed on the polyacrylonitrile（PAN） nanofibre were synthesized by means of electrospinning techno- logy combined with gas-solid reaction. A series of experiments was performed to characterize the morphology varia- tion and distribution of the nanocrystalline. The result shows that the concentration of metal salt aqueous solution affects the size and morphology of metal sulfide nanoparticles during the chelating process. Further more, these metal ions nanoparticles were attached to the surface of the nanofibre homogeneously through chelating effect which will be propitious to prevent nanoparticles from aggregation. These results suggest that the method reported here is ex- tremely effective for synthesizing PAN-metal sulfide nanocomposites which have good visible light photocatalytic activity. Further more, this method could be extended to prepare other PAN-metal halides nanocomposites, too.

关键词： Nanofibre Electrospinning Metal sulfde Visible light catalytic

Elastoplastical analysis on cylinder of different moduli in tension and compression

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Journal of Coal Science & Engineering(China) 2009年第1期15卷 66-71页

作者： WANG Wei-ming ZHANG Xiao-yan yang Zhao WANG qing-biao College of Civil Engineering and Architecture Shangdong University of Science and Technology Qingdao 266510 China

The constitutive equation was deduced. The results were obtained from theelastic and elastoplastical analysis of the cylinder sample applied with different ratios ofload on both the inner and outer sides and different moduli ratio. The factors affecting thedevelopment of the plastic field of the cylinder with finite radius were shown. The resultsshow that the different moduli ratio is the most important factor in the development of theplastic zone. The slight fluctuation of the ratio will bring multiplied increment of the displacement, which may result in the final destruction of the engineering material.

关键词： cylinder different moduli plastic zone elastoplastical analysis

Fabrication of Poly(4-vinylpyridine) Nanofiber and Fluorescent Poly(4-vinylpyridine)/Porphyrin Nanofiber by Electrospinning

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Chemical Research in Chinese Universities 2008年第6期24卷 722-725页

作者： SONG Yan ZHAN Nai-qian YU Miao yang qing-biao ZHANG Chao-qun WANG Heng-guo LI Yao-xian College of Chemistry Jilin University Changehun 130021 P. R. China School of Chemical and Material Engineering Jilin Institute of Chemical Teehology Jilin 132022 P R. China

Poly（4-vinylpyridine）（P4-VP） nanofiber and fluoresent poly（4-vinylpyridine）/porphyrin（P4-VP/TPPA） nanofiber were respectively prepared by electrospinning. The effect of the concentration of P4-VP/dimethylformamide （DMF） electrospinning solutions on the morphology of P4-VP nanofiber was investigated and it was found that the average diameter of the nanofiber of P4-VP/DMF increased with the increase of the concentration of the spinning solution. After the addition of TPPA to the P4-VP/DMF spinning solution, the diameter of P4-VP/TPPA nanofiber became even due to the increase of the conductivity of the P4-VP/DMF-TPPA solution. The photoluminescent（PL） spectral analysis indicates that the emission peak position of P4-VP/TPPA nanofiber is almost the same as that of pure TPPA at about 650 nm without peak shift, and when it was stored for 20 days, the emission peak of P4-VP/TPPA nanofiber is also at 650 nm, indicating that the fluorescent property of P4-VP/TPPA nanofiber is stable. Fourier-transform iufrared（FTIR） spectrum confirms the chemical composition of the resulting P4-VP/TPPA composite nanofiber.

关键词： Poly(4-vinylpyridine) Porphyrin Nanofiber Electrospinning

High-resolution neutronics model for ^(238)Pu production in high-flux reactors

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Nuclear Science and Techniques 2024年第5期35卷 226-236页

作者： qing-Quan Pan qing-Fei Zhao Lian-Jie Wang Bang-yang Xia Yun Cai Jin-biao Xiong Xiao-Jing Liu School of Nuclear Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610200China

We proposed and compared three methods(filter burnup,single energy burnup,and burnup extremum analysis)to build a high-resolution neutronics model for 238Pu production in high-flux *** filter burnup and single energy burnup methods have no theoretical approximation and can achieve a spectrum resolution of up to~1 eV,thereby constructing the importance curve and yield curve of the full energy *** burnup extreme analysis method combines the importance and yield curves to consider the influence of irradiation time on production efficiency,thereby constructing extreme *** three curves,which quantify the transmutation rate of the nuclei in each energy region,are of physical significance because they have similar distributions.A high-resolution neutronics model for ^(238)Pu production was established based on these three curves,and its universality and feasibility were *** neutronics model can guide the neutron spectrum optimization and improve the yield of ^(238)Pu by up to 18.81%.The neutronics model revealed the law of nuclei transmutation in all energy regions with high spectrum resolution,thus providing theoretical support for high-flux reactor design and irradiation production of ^(238)Pu.

关键词： ^(238)Pu Neutronics model High-flux reactor Spectrum resolution Spectrum optimization

Synthesis of Poly(N-vinylpyrrolidone) Nanofibers Containing Gold Nanoparticles via Electrospinning Technique

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Chemical Research in Chinese Universities 2007年第5期23卷 538-540页

作者： DU Jian-shi yang qing-biao BAI Jie WANG Shu-gang ZHANG Chao-qun LI Yao-xian Department of Chemistry Jilin University Changchun 130021 P. R. China China-Japan Union Hospital Jilin University Changchun 130031 P. R. China

Poly（N-vinylpyrrolidone）（PVP）nanofibers containing gold nanoparticles were prepared by electrospinning *** simple route was used to prepare composites on a large scale,and the syntheses are *** optical property of gold nanoparticles in PVP aqueous solution was investigated by UV-Visible absorption *** morphology of the fibers and the distribution of particles were characterized by transmission electron *** structure of the composite was characterized by Fourier transform infrared spectroscopy.

关键词： Composite nanofiber Electrospinning Poly(N-vinylpyrrolidone) Gold nanoparticle

Effect of the vortical structures on the hydrodynamic performance of a pitching hydrofoil

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Journal of Hydrodynamics 2024年第2期36卷 406-420页

作者： Rui Yuan Hui-yun Hao Qin Wu Yun-qing Liu biao Huang School of Mechanical Engineering Beijing Institute of TechnologyBeijing100081China

The objective is to study the vortical structural behaviors of a transient pitching hydrofoil and their effects on the hydrodynamic performance. The pitching motion of the hydrofoil is set to pitch up with an almost constant rate from 5° to 15° and then back to 5°, with the Reynolds number 4.4×10^(5) and the frequency 2 Hz. The results show that the main coherent structures around the pitching hydrofoil include small-scale laminar separation bubble (LSB), large-scale second vortex (SV) and trailing edge vortex (TEV) which are all vortical. The relationship between the vortical structure and the lift is investigated with the finite-domain impulse theory. It indicates that the major part of the lift is contributed by the LSB, whereas the shedding and the formation of the SV and TEV cause the fluctuation of the lift. The proper orthogonal decomposition (POD) method is applied to capture the most energetic modes, revealing that the LSB mode occupies a large amount of energy in the flow field. The dynamic mode decomposition (DMD) method accurately extracts the dominant frequency and modal characteristics, with the first mode corresponding to the mean flow, the second mode corresponding to the LSB structure and the third and fourth modes corresponding to the vortex shedding.

关键词： Hydrodynamics vortical structures finite-domain impulse theory proper orthogonal decomposition(POD) dynamic mode decomposition(DMD) Pitching hydrofoil

Exploring a new path of green and efficient utilization of sinter return fine to produce composite pellets

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Journal of Iron and Steel Research International 2024年第7期31卷 1610-1622页

作者： Yan-biao Chen Wen-guo Liu Hao Guo Jing-song Wang qing-guo Xue Hai-bin Zuo State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China MCC Capital Engineering and Research Incorporation Limited Beijing 100176China

Efficient utilization of sinter return fine is an important measure to reduce cost,increase efficiency,save energy and reduce emission.A new path of green and efficient utilization of return fine was proposed to produce composite *** metallurgical properties of composite pellets under the condition of hydrogen-rich blast furnace were *** experimental results indicate that the coated concentrate was consolidated for the composite pellets through normal Fe_(2)O_(3) *** the surface of core return fine,the liquid phase formed due to its low-melting point,assimilated the adjacent concentrate,and then consolidated with the temperature *** with regular pellets,the com-pressive strength and reduction swelling index of composite pellets were decreased,but the reducibility index and softening-melting properties were *** addition,the reduction degradation index of composite pellets was sig-nificantly higher than that of ***,adding composite pellets was conducive to indirect reduction in blast furnace,reducing fuel ratio and improving production *** to the effect of the roasting system on the metallurgical properties,the roasting temperature and time were determined as 1250℃and 30 min,*** composite pellets can be produced under the traditional pelletizing process.

关键词： Sinter Return fine Composite pellet Roasting system Metallurgical property Hydrogen-rich blast furnace

Association between childhood obesity and gut microbiota:16S rRNA gene sequencing-based cohort study

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World Journal of Gastroenterology 2024年第16期30卷 2249-2257页

作者： Xu-Ming Li qing Lv Ya-Jun Chen Lu-biao Yan Xin Xiong Laboratory Department Nanjing Medical University Affiliated Obstetrics and Gynecology Hospital(Nanjing Maternal and Child Health Hospital)Nanjing 210004Jiangsu ProvinceChina Department of Pediatrics Shenzhen University General HospitalShenzhen 518055Guangdong ProvinceChina Department of Inspection Division Women’s Hospital of Nanjing Medical University(Nanjing Maternity and Child Health Care Hospital)Nanjing 210004Jiangsu ProvinceChina Department of Pediatrics Women’s Hospital of Nanjing Medical University(Nanjing Maternity and Child Health Care Hospital)Nanjing 210004Jiangsu ProvinceChina Department of Neonatology Chenzhou First People’s HospitalChenzhou 423000Hunan ProvinceChina

BACKGROUND This study aimed to identify characteristic gut genera in obese and normal-weight children(8-12 years old)using 16S rDNA *** research aimed to provide insights for mechanistic studies and prevention strategies for childhood *** normal-weight and thirty age-and sex-matched obese children were *** and body measurements were collected,and fecal samples underwent 16S rDNA *** differences in body mass index(BMI)and body-fat percentage were observed between the *** of gut microbiota diversity revealed lowerα-diversity in obese *** in gut microbiota composition were found between the two *** and Firmicutes were more abundant in the obese group,while Bacteroides and Sanguibacteroides were more prevalent in the control *** To identify the characteristic gut genera in obese and normal-weight children(8-12-year-old)using 16S rDNA sequencing,and provide a basis for subsequent mechanistic studies and prevention strategies for childhood *** Thirty each normal-weight,1:1 matched for age and sex,and obese children,with an obese status from 2020 to 2022,were included in the control and obese groups,*** information was collected through questionnaires and body measurements were obtained from both obese and normal-weight *** samples were collected from both groups and subjected to 16S rDNA sequencing using an Illumina MiSeq sequencing platform for gut microbiota diversity *** Significant differences in BMI and body-fat percentage were observed between the two *** Ace and Chao1 indices were significantly lower in the obese group than those in the control group,whereas differences were not significant in the Shannon and Simpson ***-Wallis tests indicated significant differences in unweighted and weighted UniFrac distances between the gut microbiota of normal-weight and obese children(P<0.01),suggest

关键词： Childhood obesity Gut microbiota 16S rDNA sequencing Diversity analysis Genus identification Body mass index