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Synthesis and Evaluation of Sulfoxide-Functionalized BODIPYs as Chemosensors for Thiols

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Chinese Journal of Chemistry 2015年第7期33卷 711-716页

作者： Chunchang zhao haifeng Jiang Key Laboratory for Advanced Materials and Institute of Fine Chemicals East China University of Seience & Technology Shanghai 200237 China

BODIPY-based fluorescent chemosensors bearing sulfoxide function were designed and evaluated. Thiols triggered sulfoxide→sulfide transduction in these probes leads to an obvious red-shift in absorption and dramatic f... 详细信息

关键词： sulfoxide→sulfide transfer Cysteine ratiometric living cells reduction

DETERMINATION OF INTERFACIAL MECHANICAL PARAMETERS FOR AN Al/EPOXY/Al_2O_3 SYSTEM BY USING PEEL TEST SIMULATIONS

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Acta Mechanica Solida Sinica 2008年第3期21卷 198-206页

作者： Xuemei You haifeng zhao Yueguang Wei State-Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Aeademyof Science Beijing 100190 China

Peel test measurements and simulations of the interfacial mechanical parameters for the Al/Epoxy/Al2O3 system are performed in the present investigation. A series of Al film thicknesses between 20 and 250 microns and three peel angles of 90, 135 and 180 degrees are considered. Two types of epoxy adhesives are adopted to obtain both strong and weak interface adhesions. A finite element model with cohesive zone elements is used to identify the interfacial parameters and simulate the peel test process. By simulating and recording normal stress near the crack tip, the separation strength is obtained, Furthermore, the cohesive energy is identified by comparing the simulated steady-state peel force and the experimental result. It is found from the research that both the cohesive energy and the separation strength can be taken as the intrinsic interfacial parameters which are dependent on the thickness of the adhesive layer and independent of the film thickness and peel angle.

关键词： peel test interface toughness cohesive zone model energy release rate

Modeling and Characteristic Analysis of Visco-Hyperelastic Film Based on Biaxial Tensile Experiment

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第6期36卷 986-994页

作者： zhao haifeng ZHANG Ya LIShizhong LUO Huaan Faculty of Mechanical and Electrical Engineering Nanjing Vocational College of Information TechnologyNanjing 210023P.R.China Faculty of Mechanical and Electrical Engineering North University of ChinaTaiyuan 030051P.R.China

Dielectric elastomers(DEs)show complex mechanical behaviors with different boundary conditions,geometry sizes,and *** this study,a three-component linear visco-hyperelastic model of DE film is developed based on equibiaxial *** applying hereditary integrals to analyze multiple-segment loading processesof film stretching,the model parameters are extracted by fitting the visco-hyperelastic film model to the experimental *** demonstrate the performance of proposed model,the obtained predictive results are compared with the experimental results under different equibiaxial loading *** good agreement between them shows that the linear visco-hyperelastic model is a promising tool for analytically investigating the property of pre-stretched DE ***,the Prony series coefficients are calculated according to the relaxation *** is helpful for simulation analysis using commercial finite element software.

关键词： dielectric elastomers equibiaxial tension Prony series visco-hyperelastic

Communication Effect of Passengers on Information Diffusion in Metro Emergency

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Wuhan University Journal of Natural Sciences 2017年第6期22卷 503-509页

作者： zhao haifeng SUN Yanqiu School of Management and Economics Tongji UniversityShanghai 200092 China

Information diffusion is significant for emergencymanagement as it can decide the severity of accidents. In this paper, we set up a communication model of passengers for the metroemergency. In the model, four categories of passengers are definedas unknown passengers, supportive passengers, neutral passengers and opposed passengers. Three passengers’ characteristics are taken into account, such as spreading desire, the trustworthinessand the passengers’ uncertainty about their opinions. From thesimulation results, we can see that the passengers’ uncertainty about their opinions has a positive correlation with the time ofpassengers’ opinions reaching consensus, while other two factorsboth have a negative correlation. The result is useful for metroofficials to guide and control emergency information.

关键词： metro emergency communication information diffusion multi-agent simulation

One-step Synthesis of Shape-controllable Gold Nanoparticles and Their Application in Surface-enhanced Raman Scattering

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Journal of Materials Science & Technology 2013年第7期29卷 613-618页

作者： Lanlan Sun Dongxu zhao Meng Ding haifeng zhao Zhenzhong Zhang Binghui Li Dezhen Shen State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of Sciences

Gold nanoparticles （NPs） of various shapes were synthesized by a one-step method at ambient temperature in the presence of NaCl. 2-mercaptosuccinic acid （MSA） was used as both reducing agent and stabilizing agent. The shapes of gold NPs were controllable by simply tuning S/Au ratio （S is from MSA molecule, and S/Au ratio is controlled by tuning the volume of added MSA solution）, and triangle, polygonal and spherical nanoparticles were obtained. This result suggested a new way to consider the effects of MSA on the growth of nanoparticles, which showed that MSA is a strong capping agent and facilitates more uniform growth of nanoparticles in every dimension. And other important factors on nanoparticles growth including NaCl and temperature were discussed. Furthermore, a typical probe molecule, 4-aminothiophenol （4-ATP） was used to test the surface-enhanced Raman scattering （SERS） activity of these gold NPs and the results indicated good Raman activity on these substrates. And the enhancement factor （EF） at 1078 cm^- 1 （a1） was estimated to be as large as 6.3 × 10^4 and 5.5 × 10^4 for triangular plates and truncated particles, respectively.

关键词： Nanoparticle Shape Controlled synthesis Surface-enhanced Raman scattering (SERS)

Radix Astragali-induced differentiation of rat bone marrow-derived mesenchymal stem cells

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Neural Regeneration Research 2009年第7期4卷 497-502页

作者： Xinsheng Wang haifeng Li Ying zhao Xiaoli Zhang Aihua Bo Central Laboratory of Hebei North University Zhangjiakou 075029 Hebei Province China

BACKGROUND： Chemical induction has been shown to be effective at promoting the differentiation of bone marrow-derived mesenchymal stem cells （MSCs）. However, these inductors have cytotoxicity side effects that may damage cells over time. Traditional Chinese medicines avoid this disadvantage while still producing effective induction. OBJECTIVE： To investigate the influence of RadixAstragafi （Huangql） on the differentiation of MSCs. DESIGN, TIME AND SETTING： In vitro study of traditional Chinese medicine in neural stem cell differentiation. The experiment was performed at the Central Laboratory of Hebei North University between April and June 2007. MATERIALS： Radix Astragafi solution （lot No. 060105; license No. Z53021585） was purchased from Dali Pharmaceutical Co., Ltd., China; rabbit anti-rat nestin, rabbit anti-rat neuron-specific enolase （NSE）, mouse anti-rat microtubule-associated protein 2, and rabbit anti-rat glial fibrillary acidic protein were purchased from Wuhan Boster, China. METHODS： Whole bone marrow was isolated from the femur and tibia of 6-week-old male Wistar rats and subcultured. The fourth passage of MSCs were harvested and induced by different concentrations （50, 100, 200, 400 g/L） of Radix Astragali. MAIN OUTCOME MEASURES： Hematoxylin-eosin staining was used to observe MSC morphology after 24 hours of induction. Immunocytochemistry was employed to observe the expression of NSE （specific neuronal marker）, nestin （marker of neural stem cell）, glial fibrillary acidic protein and microtubule-associated protein 2 （markers of astrocytes）. RESULTS： Following Radix Astragali treatment, changes occurred in cell morphology including： cell body pyknosis; thin and long processes formed in some cells, with growth corresponding to drug concentration and induction time; and the formation of network-like connections between some cells. With increasing drug concentration and induction time, nestin expression was upregulated, and the number of positive

关键词： Radix Astragafi mesenchymal stem cells inductive differentiation

Effect of succinic acid deamidation-induced modification on wheat gluten

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Frontiers of Chemical Science and Engineering 2009年第4期3卷 386-392页

作者： Lan LIAO Mouming zhao haifeng zhao Jiaoyan REN Chun CUI Xiao HU College of Light Industry and Food Sciences South China University of TechnologyGuangzhou 510640China

The effect of succinic acid deamidationinduced modification on wheat gluten was investigated in the present *** changes of surface hydrophobicity,functional properties,secondary structure,and sensibility of proteolysis of modified samples were *** solubility of deamidated proteins increased in the isoelectric region of untreated wheat *** isoelectric point of succinic acid deamidated wheat gluten was shifted to a basic pH and existed in the broad pH *** property and molecular flexibility of wheat gluten were improved after the *** hydrolysis degree of the hydrolysates in proteolysis with flavorzyme and pancreatin increased after succinic acid ***,succinic acid deamidation-induced modification resulted in little change in molecular weight and secondary structure of the ***,succinic acid could facilitate unfolding protein *** addition,it could improve protein-water interactions,surface properties,and sensibility of the proteolysis of the deamidated wheat gluten.

关键词： wheat gluten deamidation succinic acid functional properties protein conformation sensibility of proteolysis

Water‑immersion softening mechanism of coal rock mass based on split Hopkinson pressure bar experiment

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International Journal of Coal Science & Technology 2022年第4期9卷 122-134页

作者： Zhiyuan Liu Gang Wang Jinzhou Li Huaixing Li haifeng zhao Hongwei Shi Jianli Lan School of Petroleum Engineering China University of PetroleumBeijingBeijing 102249China Mine Disaster Prevention and Control-Ministry of State Key Laboratory Breeding Base Shandong University of Science and TechnologyQingdao 266590China College of Safety and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China

The coal mining process is afected by various water sources such as groundwater and coal seam water *** the dynamic mechanical parameters of water-immersed coal is helpful for coalmine safe *** impact compression tests were performed on coal with diferent moisture contents by using theϕ50 mm Split Hopkinson Pressure Bar(SHPB)experimental system,and the dynamic characteristics and energy loss laws of water-immersed coal with diferent compositions and water contents were *** analysis and discussion,it is found that:(1)When the moisture content of the coal sample is 0%,30%,60%,the stress,strain rate and energy frst increase and then decrease with time.(2)When the moisture content of the coal sample increases from 30%to 60%,the stress“plateau”of the coal sample becomes more obvious,resulting in an increase in the compressive stress stage and a decrease in the expansion stress stage.(3)The increase of moisture content of the coal sample will afect its impact deformation and failure *** the moisture content is 60%,the incident rod end and the transmission rod end of the coal sample will have obvious compression failure,and the middle part of the coal sample will also experience expansion and deformation.(4)The coal composition ratio suitable for the coal immersion softening impact experiment is optimized.

关键词： Coal immersion softening Dynamic compressive response Split Hopkinson pressure bar Softening mechanism model

Structural basis for a homodimeric ATPase subunit of an ECF transporter

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Protein & Cell 2013年第10期4卷 793-801页

作者： Chengliang Chai You Yu Wei Zhuo haifeng zhao Xiaolu Li Na Wang Jijie Chai Maojun Yang College of Biological Sciences China Agricultural UniversityBeijing 100083China MOE Key Laboratory of Protein Sciences Tsinghua-Peking Center for Life SciencesSchool of Life SciencesTsinghua UniversityBeijing 100084China National Institute of Biological Sciences Beijing 102206China

The transition metal cobalt,an essential cofactor for many enzymes in prokaryotes,is taken up by several specifi c transport *** CbiMNQO protein complex be-longs to type-1 energy-coupling factor(ECF)transporters and is a widespread group of microbial cobalt *** is the ATPase subunit(A-component)of the cobalt transporting system in the gram-negative thermo-philic bacterium Thermoanaerobacter *** we report the crystal structure of a nucleotide-free CbiO at a resolution of 2.3Å.CbiO contains an N-terminal canonical nucleotide-binding domain(NBD)and C-termi-nal helical *** and biochemical data show that CbiO forms a homodimer mediated by the NBD and the C-terminal *** mainly via conserved hydrophobic amino acids between the two C-terminal do-mains result in formation of a four-helix *** comparison with other ECF transporters suggests that non-conserved residues outside the T-component bind-ing groove in the A component likely act as a specifi city determinant for T ***,our data provide information on understanding of the structural organiza-tion and interaction of the CbiMNQO system.

关键词： CbiO Cobalt ECF ATPase Thermoanaero-bacter tengcongensis