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Chinese Journal of Chemical Engineering 2021年第3期34卷 198-205页

作者： Nanhua wu Xiaohua Lu rong An Xiaoyan Ji Division of Energy Science/Energy Engineering LuleåUniversity of Technology97187 LuleåSweden State Key Laboratory of Materials-Oriented and Chemical Engineering Nanjing Tech UniversityNanjing 211816China Key Laboratory of Advanced Catalytic Materials and Technology School of Petrochemical EngineeringChangzhou UniversityChangzhou 213164China Herbert Gleiter Institute of Nanoscience Nanjing University of Science&TechnologyNanjing 210094China

Abnormal melting point depression of metal nanoparticles often occurs in heterogeneous catalytic reactions,which leads to a reduction in the stability of reactive *** study this abnormal phenomenon,the original and surface-energy modified Gibbs-Thomson equations were analyzed in this work and further modified by considering the effect of the *** results revealed that the original Gibbs-Thomson equation was not suitable for the particles with radii smaller than 10 ***,the performance of the surface-energy modified Gibbs-Thomson equation was improved,and the deviation was reduced to(-350-100)K,although further modification of the equation by considering the interfacial effect was necessary for the small particles(r<5 nm).The new model with the interfacial effect improved the model performance with a deviation of approximately-50 to 20 K,where the interfacial effect can be predicted quantitatively from the thermodynamic properties of the metal and ***,the micro-wetting parameterα_W can be used to qualitatively study the overall impact of the substrate on the melting point depression.

关键词： Melting point depression Metal nanoparticle Gibbs–Thomson equation Substrate Interfacial effect

A Note on the Generalized Marcinkiewicz Integral Operators with Rough Kernels

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Acta Mathematica Sinica,English Series 2012年第12期28卷 2395-2406页

作者： Yu rong wu Huo Xiong wu School of Mathematical Sciences Xiamen University School of Mathematical Sciences Fudan University

In this paper, we study the generalized Marcinkiewicz integral operators MΩ,r on the product space Rn ×Rm. Under the condition that Ω is a function in certain block spaces, which is optimal in some senses, the boun... 详细信息

关键词： Marcinkiewicz integral Triebel-Lizorkin space vector-valued multiplier theorem rough kernel product space

Chemoselective Catalytic Hydrogenation of Nitroarenes Using MOF-Derived Graphitic Carbon Layers Encapsulated Ni Catalysts

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China Petroleum Processing & Petrochemical Technology 2021年第3期23卷 40-49页

作者： wu Genghuang rong Junfeng SINOPEC Research Institute of Petroleum Processing Beijing 100083

Replacement of precious noble metal catalysts with cost-effective,non-noble heterogeneous catalysts for chemoselective hydrogenation of nitroarenes holds tremendous promise for the clean synthesis of nitrogen-containing *** carbon layers encapsulated Ni catalysts(Ni@CN)are generated by a facile,scalable and straightforward strategy via the pyrolysis of 2,5-pyridinedicarboxylic acid coordinated Ni-MOF acting as the *** properties of the Ni@CN catalysts have been investigated by X-ray diffraction,scanning electron microscopy,transmission electron microscopy,elemental analysis and N2 adsorption-desorption *** Ni@CN catalysts were found to be highly efficient in the chemoselective hydrogenation of various nitroarenes with other functional groups towards corresponding anilines under mild reaction conditions(85℃,1.0 MPa of H2 pressure).Based on the results of controlled tests,the catalytic activity can be attributed to the Ni NPs,while the presence of graphitic carbon layers favors the preferential adsorption of the nitro *** recyclability and anti-sulfur poisoning capability of Ni@CN were also investigated.

关键词： chemoselective hydrogenation carbon encapsulated metal-organic frameworks nickel nanoparticles nitroarenes

Mesopolymer modified with palladium phthalocyaninesulfonate as a versatile photocatalyst for phenol and bisphenol A degradation under visible light irradiation

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Journal of Environmental Sciences 2013年第8期25卷 1687-1695页

作者： rong Xing Lin wu Zhenghao Fei Peng wu Jiangsu Provincial Key Laboratory of Coastal Wetland Bioresources and Environmental Protection Yancheng Teachers University Yancheng 224002 China Shanghai Key Laboratory of Green Chemistry and Chemical Processes Department of Chemistry East China Normal University Shanghai 200062 China

A novel versatile photocatalyst, FDU-PdPcS, was prepared by immobilizing palladium phthalocyaninesulfonate （PdPcS） onto the FDU-15 mesopolymer via multi-step chemical modification processes involving chloromethylation of the FDU-15 mesopolymer first with chloromethyl methyl ether, a subsequent amination reaction with ethylenediamine, and finally modification with palladium phthalocyaninesulfonate via ionic interaction. The obtained FDU-PdPcS photocatalyst was characterized by the X-ray diffraction （XRD）, UV-Vis spectrosopy and inductively coupled plasma （ICP） techniques. This photocatalyst not only affords a high dispersion of monomeric PdPcS molecules, which may further be stabilized by the π-electron of benzene rings of FDU-15, but also provides a number of diamino groups inside the mesopores, which could be advantageous for the photodegradation of phenolic pollutants. In photodegradation studies of phenolic pollutants, the FDU-PdPcS catalyst exhibited excellent visible light photocatalytic activity and reusability. The photodegradation products of phenol and bisphenol A were investigated by the gas chromatoghraphy-mass spectrometry （GC-MS） technique. The results showed that the photodegradation products were composed of carboxylic acids and CO2. Isopropanol, sodium azide and benzoquinone were used as hydroxyl radical （OH.）, singlet oxygen （1O2） and superoxide radical （O2.-） scavengers, respectively. The results suggested that 1O2 and O2. were the prominent active species during the photodegradation process. A possible mechanism for the photodegradation of phenol was also discussed.

关键词： mesopolymer phthalocyanine photocatalysis visible light phenolic pollutants

Upper Bounds for Ruin Probabilities under Stochastic Interest Rate and Optimal Investment Strategies

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Acta Mathematica Sinica,English Series 2012年第7期28卷 1421-1430页

作者： Jin Zhu LI rong wu School of Mathematical Sciences and LPMC Nankai University

In this paper, we study the upper bounds for ruin probabilities of an insurance company which invests its wealth in a stock and a bond. We assume that the interest rate of the bond is stochastic and it is described by a Cox-Ingersoll-Ross （CIR） model. For the stock price process, we consider both the case of constant volatility （driven by an O U process） and the case of stochastic volatility （driven by a CIR model）. In each case, under certain conditions, we obtain the minimal upper bound for ruin probability as well as the corresponding optimal investment strategy by a pure probabilistic method.

关键词： Cox Ingersoll-Ross model jump-diffusion model optimal investment Ornstein Uhlen- beck (O-U) process ruin probability stochastic interest rate

The Gerber-Shiu Discounted Penalty Function for a Compound Binomial Risk Model with By-claims

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Acta Mathematicae Applicatae Sinica 2015年第1期31卷 181-190页

作者： Jin-zhu LI rong wu School of Mathematical Sciences and LPMC Nankai University

A recursive formula of the Gerber-Shiu discounted penalty function for a compound binomial risk model with by-claims is obtained. In the discount-free case, an explicit formula is given. Utilizing such an explicit expression, we derive some useful insurance quantities, including the ruin probability, the density of the deficit at ruin, the joint density of the surplus immediately before ruin and the deficit at ruin, and the density of the claim causing ruin.

关键词： compound binomial risk model Gerber-Shiu function by-claims

On the Gerber-Shiu Discounted Penalty Function for a Surplus Process Described by PDMPs

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Acta Mathematica Sinica,English Series 2010年第5期26卷 951-962页

作者： Jing Min HE rong wu College of Science Tianjin University of Technology Tianjin 300384 P. R. China School of Mathematical Sciences Nankai University Tianjin 300071 P. R. China

In this paper, we investigate the Gerber-Shiu discounted penalty function for the surplus process described by a piecewise deterministic Markov process （PDMP）. We derive an integral equation for the Gerber-Shiu discounted penalty function, and obtain the exact solution when the initial surplus is zero. Dickson formulae are also generalized to the present surplus process.

关键词： Gerber-Shiu discounted penalty function piecewise deterministic Markov process ulti- mate ruin probability Volterra integral equation

Asymptotic Ruin Probabilities of the Renewal Model with Constant Interest Force and Dependent Heavy-tailed Claims

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Acta Mathematicae Applicatae Sinica 2011年第2期27卷 329-338页

作者： Jin-zhu Li rong wu School of Mathematical Sciences and LPMC Nankai University Tianjin 300071 China

In this paper, we investigate the asymptotic behavior for the finite- and infinite-time ruin probabilities of a nonstandard renewal model in which the claims are identically distributed but not necessarily inde- pendent. Under the assumptions that the identical distribution of the claims belongs to the class of extended regular variation （ERV） and that the tails of joint distributions of every two claims are negligible compared to the tails of their margins, we obtain the precise approximations for the finite- and infinite-time ruin probabilities.

关键词： asymptotic behavior extended regular variation negligible joint tails ruin probability

Conditionally Reprogrammed Human Normal Airway Epithelial Cells at ALI: A Physiological Model for Emerging Viruses

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Virologica Sinica 2020年第3期35卷 280-289页

作者： Xuefeng Liu Yuntao wu Lijun rong Department of Pathology Center for Cell ReprogrammingGeorgetown University Medical CenterWashingtonDCUSA Department of Oncology Lombardi Comprehensive Cancer CenterGeorgetown University Medical CenterWashingtonDCUSA National Center for Biodefense and Infectious Diseases School of Systems BiologyGeorge Mason UniversityManassasVA 20110USA Department of Microbiology and Immunology University of Illinoi at ChicagoChicagoIL 60612USA

Cancer cell lines have been used widely in cancer biology, and as biological or functional cell systems in many biomedical research fields. These cells are usually defective for many normal activities or functions due to significant genetic and epigenetic changes. Normal primary cell yields and viability from any original tissue specimens are usually relatively low or highly variable. These normal cells cease after a few passages or population doublings due to very limited proliferative capacity. Animal models(ferret, mouse, etc.) are often used to study virus-host interaction. However, viruses usually need to be adapted to the animals by several passages due to tropism restrictions including viral receptors and intracellular restrictions. Here we summarize applications of conditionally reprogrammed cells(CRCs), long-term cultures of normal airway epithelial cells from human nose to lung generated by conditional cell reprogramming(CR) technology, as an ex vivo model in studies of emerging viruses. CR allows to robustly propagate cells from non-invasive or minimally invasive specimens, for example, nasal or endobronchial brushing. This process is rapid(2 days) and conditional. The CRCs maintain their differentiation potential and lineage functions, and have been used for studies of adenovirus, rhinovirus, respiratory syncytial virus, influenza viruses, parvovirus, and SARS-CoV. The CRCs can be easily used for airliquid interface(ALI) polarized 3 D cultures, and these coupled CRC/ALI cultures mimic physiological conditions and are suitable for studies of viral entry including receptor binding and internalization, innate immune responses, viral replications, and drug discovery as an ex vivo model for emerging viruses.

关键词： Normal cells Cell senescence Conditional reprogramming Physiological conditions Functional models Air-liquid interface(ALI) Emerging viruses SARS-CoVs

Two New Fourth-Order Three-Stage Symplectic Integrators

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Chinese Physics Letters 2011年第7期28卷 1-4页

作者： LI rong wu Xin School of Science Nanchang UniversityNanchang 330031

Two new fourth-order three-stage symplectic integrators are specifically designed for a family of Hamiltonian systems,such as the harmonic oscillator,mathematical pendulum and latticeφ4 *** the nonintegrable latticeφ4 system is taken as a test model,numerical comparisons show that the new methods have a great advantage over the second-order Verlet symplectic integrators in the accuracy of energy,become explicitly better than the usual non-gradient fourth-order seven-stage symplectic integrator of Forest and Ruth,and are almost equivalent to a fourth-order seven-stage force gradient symplectic integrator of *** the most important advantage,the new integrators are convenient for solving the variational equations of many Hamiltonian systems so as to save a great deal of the computational cost when scanning a lot of orbits for chaos.

关键词： symplectic Hamiltonian integrable