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Effect of bismuth species on propylene aromatization over BiHZSM-5 catalysts

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Chinese Journal of chemistry 1994年第4期12卷 295-304页

作者： MIAO, Cheng-Mingdepartment of chemistry, jiangsu Institute of Education, nanjing, jiangsu 210013, ChinaWU, Chuan-Chang FENG, Lin department of chemistry, nanjing university, nanjing, jiangsu 210008, China department of chemistry Jiangsu Institute of Education Nanjing Jiangsu 210013 China department of chemistry Nanjing University Nanjing Jiangsu 210008 China

The catalytic behavior of Bi-impregnated HZSM-5 zeolites in propylene aroma-tization and the surface properties of the zeoh'tes were determined by microreactor, XRD, XPS, NH3-TPD and IR-TPD. The mechanism of the reaction and the effect of surface properties of the zeolites on the reaction were also investigated. Experimental data showed that Bi-impregnation made the strength of B-acid sites decrease, the strength of L-acid sites and the concentration of both strong B-acid sites and strong L-acid sites increase. Bi-impregnation also induced sub-strong acid sites. These were the factors that made the aromatic products of the reaction increase. The strong interaction between the impregnant and zeolite surface reached maximum at Bi2O3 = 3.5 wt%. Above this value, covering effect of impregnant caused a decrease of aromatic products.

关键词： Aromatization Bi-impregnation ZSM-5 Propylene.

MOF-Derived Iron-Cobalt Phosphide Nanoframe as Bifunctional Electrocatalysts for Overall Water Splitting

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Energy & Environmental Materials 2024年第6期7卷 312-320页

作者： Yanqi Yuan Kun Wang Boan zhong Dongkun Yu Fei ye Jing Liu Joydeep Dutta Peng zhang School of Materials Science and Engineering Shanghai Jiao Tong University800 Dongchuan RoadShanghai 200240China Functional NanoMaterials Group Department of Applied PhysicsSchool of Engineering SciencesKTH Royal Institute of TechnologyHannes Alfv´ens v¨ag 1211419StockholmSweden Shanghai Key Laboratory of Hydrogen Science Shanghai 200240China

Transition metal phosphides(TMPs)have emerged as an alternative to precious metals as efficient and low-cost catalysts for water *** doping and morphology control are effective approaches to further improve the performance of ***,Fe-doped CoP nanoframes(Fe-CoP NFs)with specific open cage configuration were designed and *** unique nano-framework structured Fe-CoP material shows overpotentials of only 255 and 122 mV at 10 mA cm^(−2)for oxygen evolution reaction(OER)and hydrogen evolution reaction(HER),respectively,overwhelming most transition metal *** overall water splitting,the cell voltage is 1.65 V for Fe-CoP NFs at a current density of 10 mA cm^(−2),much superior to what is observed for the classical nanocubic ***-CoP NFs show no activity degradation up to 100 h which contrasts sharply with the rapidly decaying performance of noble metal catalyst *** superior electrocatalytic performance of Fe-CoP NFs due to abundant accessible active sites,reduced kinetic energy barrier,and preferable*O-containing intermediate adsorption is demonstrated through experimental observations and theoretical *** findings could provide a potential method for the preparation of multifunctional material with hollow structures and offer more hopeful prospects for obtaining efficient earth-abundant catalysts for water splitting.

关键词： electrocatalysis hollow structure iron-doped cobalt phosphide MOF overall water splitting

LIMIT CYCLES AND BIFURCATION CURVES FOR THE QUADRATIC DIFFERENTIAL SYSTEM (III)_(m=0) HAVING THREE ANTI-SADDLES (I)

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Chinese Annals of Mathematics,Series B 1996年第2期17卷 167-174页

作者： ye YANQIAN department of Mathematics, nanjing university, nanjing 210008, China. 南京大学数学系江苏南京

For the quadratic system: x=-y+δx + lx2 + ny2, y=x(1+ax-y) under conditions -10 the author draws in the (a, ()) parameter plane the global bifurcationdiagram of trajectories around O(0,0). Notice that when na2+l < 0 ... 详细信息

关键词： Quadrtic systen Anti-saddle Bifurcation curve Limit cycle

A theoretical analysis and its application of the second order EC' reactions at microelectrodes under steady-state conditions

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Chinese Journal of chemistry 1993年第4期11卷 308-315页

作者： ZHUANG,Qian-Kun CHEN,Hong-Yuan department of chemistry,nanjing university,nanjing,jiangsu 210008 department of chemistry Nanjing University Nanjing Jiangsu 210008

With a new approach,the general current expressions of two typical second order catalytic reactions are obtained for disk,hemispherical and spherical microelectrodes under steady-state *** approach is based on the concept of reaction *** the second order EC' reactions,we also discussed how it is possible to observe pseudo-first order or second order *** consideration allows the study of the fast chemical reactions and systems where the bulk concentrations of the reactants are nearly *** of Fe^(3+)(EDTA) with H_2O_2 was selected as an example of a rapid catalytic reaction.

关键词： der A theoretical analysis and its application of the second order EC reactions at microelectrodes under steady-state conditions

L-R smash products for bimodule algebras

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Progress in Natural Science:Materials International 2006年第6期16卷 580-587页

作者： zhang Liangyun (department of Mathematics, nanjing Agricultural university, nanjing 210095, China department of Mathematics, nanjing university, nanjing 210008, China) department of Mathematics Nanjing Agricultural University Nanjing 210095 China department of Mathematics Nanjing U-niversity Nanjing 210008 China

In this paper, we prove that the L-R smash product A(?)H is exactly the twisted smash product A * H if H is a finite dimensional cocommutative Hopf algebra, and give a sufficient and necessary condition for L-R smash products to be bialgebras (Hopf algebras) . For any finite dimensional coquasitriangular Hopf algebra (H,σ), we prove that the L-R smash product H(?)H is semisimple Artinian if H is semisimple and H * is unimodular. In particular, the L-R smash product D(H)* (?)D(H)* semisimple Artinian if the Drin-fel'd double D(H) is semisimple.

关键词： bimodule algebras L-R smash products coquasitriangular Hopf algebras Long bialgebras.

Maschke-type theorem and Morita context over weak Hopf algebras

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Science China Mathematics 2006年第5期49卷 587-598页

作者： zhang Liangyun College of Science, nanjing Agricultural university, nanjing 210095, China department of Mathematics, nanjing university, nanjing 210008, China College of Science Nanjing Agricultural University Nanjing China department of Mathematics Nanjing University Nanjing China

This paper gives a Maschke-type theorem over semisimple weak Hopf algebras,extends the well-known Maschke-type theorem given by Cohen and Fishman and constructs a Morita context over weak Hopf algebras.

关键词： weak Hopf algebra, smash product, Maschke-type theorem, Morita context.

A GOLDSTEIN'S TYPE PROJECTION METHOD FOR A CLASSOF VARIANT VARIATIONAL INEQUALITIES

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Journal of Computational Mathematics 1999年第4期17卷 425-434页

作者： Bing-sheng He(department of Mathematics, nanjing university, nanjing 210008, China) department of Mathematics Nanjing University Nanjing 210008 China

Some optimization problems in mathematical programming can be translated to a variant variational inequality of the following form: Find a vectoru*, such that This paper presents a simple iterative method for solving this class of variational inequalities. The method can be viewed as an extension of theGoldstein's projection method. Some results of preliminary numerical experiments are given to indicate its applications.

关键词： Variational inequality Goldstein projection method.

Direct　Electron－transfer　Reaction　of　Cytochrome　C　at　a　Bare　Spectrographic　Graphite　Electrode

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Chemical Research in Chinese Universities 1995年第1期11卷 22-27页

作者： YU Ai-min CHEN Hong-yuan and HAN Ji-lin(department of chemistry , nanjing university , nanjing , 210008) nanjing UNIV DEPT CHEMNANJING 210008PEOPLES R CHINA

he electrochemistry of cytochrome C was investigated at a spectrographicgraphite electrode. In phosphate buffer solution (pH= 7. 0) , cytochrome C showedstable and quasi-reversible response. The formal potential E￣(o') was 0. 015 V (at25℃ , vs. SCE) and the heterogeneous electron transfer rate constant k_s obtainedvaried form 1. 10×10￣(-3) cm · s￣(-1) to 1. 80k×10￣(-3) cm · s￣(-1). The thermodynamic pa-rameters of the electron transfer reaction of cvtochrome C was also estimated. Fur-thermore, the effect of the various electrode surface states on the electrochemistryof cytochrome C was discussed.

关键词： Cytochrome C direct electrochemistry Spectrographic graphite elec-trode Electron transfer Rate constant

Preparation of alumina-pillared layered tetratitanates with different interlayer spacings

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Chinese Journal of chemistry 1994年第6期12卷 557-561页

作者： HOU, Wen-Hua YAN, Qi-Jie PENG, Bing-Cheng FU, Xian-Cai department of chemistry, nanjing university, nanjing, jiangsu 210008, China department of chemistry Nanjing University Nanjing Jiangsu 210008 China

The synthesis of pillared clays have led to the development of new materialswith suitable pore size and sufficient stability to be used as shape-selective catalystsand molecular sieves. There are numerous layered inorganic oxides which havethe potential to undergo ion-exchange reactions analogous to those observed withclays, but the nonswelling nature of most ionic layered oxides generally prevents

关键词： Layered tetratitanate alumina pillaring interlayer spacing.