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Zhang X.,Nanjing University of Science and Technology | Hu Z.,Nanjing University of Science and Technology | Pu Y.,Shanxi Applied Physics and Chemistry Research Institute | Chen S.,Nanjing University of Science and Technology | And 4 more authors.
Journal of Power Sources | Year: 2012

A series of sulfonated poly(p-phenylene-co-aryl ether ketone) (SPP-co-PAEK) membranes are successfully prepared from 2,5-dichloro-3′- sulfobenzophenone and 2,2′-bis[4-(4-chlorobenzoyl)] phenoxyl perfluoropropane through Ni(0)-catalyzed copolymerization for polymer electrolyte membrane fuel cell (PEFC) applications. The obtained SPP-co-PAEKs have fairly high reduced viscosities and give ductile and transparent membranes with good mechanical strength. All the membranes exhibit comparable or even better proton conductivities than that of Nafion 112 in the full hydrate state. In addition, the membranes showed almost isotropic proton conductive behavior with σ/σ values in the range of 0.85-0.92. Fuel cell operation using SPP-co-PAEK(3/1) (IEC = 2.0 meq g -1, thickness of 38 μm, feed gases: H 2/air) exhibited rather good performances: open circuit voltage of 0.94 V, cell voltage at 1.0 A cm -2 of 0.61 V, and output at 1.7 A cm -2 of 0.85 W cm -2 under 90 °C and 82/68% relative humidity condition. The results suggested that these SPP-co-PAEK membranes are promising candidates for PEFC applications. © 2012 Elsevier B.V. Source

Zhou H.-F.,Xian University of Science and Technology | Zhou Y.,Xian University of Science and Technology | Zhang X.-P.,Shanxi Applied Physics and Chemistry Research Institute | Tan S.-C.,Xian University of Science and Technology
Kongzhi yu Juece/Control and Decision | Year: 2015

For the insufficient similarity concepts for categorical variables, a new more reasonable concept is proposed. Firstly, a data set is organized into an undirected graph by the new definition. The clustering process is converted into the problem of determining connected components in the undirected graph. Then a novel clustering algorithm for categorical variables based on connected components is proposed. In order to analyze the clustering results quantitatively, a new index is proposed for the known labels. Finally, the experimental results show that the proposed algorithm has a higher clustering precision and faster execution speed compared with several existing ones. ©, 2015, Northeast University. All right reserved. Source

Liu Y.,Beijing Institute of Technology | Zhang R.,Shanxi Applied Physics and Chemistry Research Institute | Feng C.-G.,Beijing Institute of Technology | Yang L.,Beijing Institute of Technology | Zhang T.-L.,Beijing Institute of Technology
Central European Journal of Energetic Materials | Year: 2015

The crystal structures, density of states, energy gap, thermodynamic properties, impact sensitivities and morphology of beryllium carbohydrazide perchlorate ([Be(CHZ)3](ClO4)2), magnesium carbohydrazide perchlorate ([Mg(CHZ)3](ClO4)2), calcium carbohydrazide perchlorate ([Ca(CHZ)3] (ClO4)2), strontium carbohydrazide perchlorate ([Sr(CHZ)3](ClO4)2) and barium carbohydrazide perchlorate ([Ba(CHZ)3](ClO4)2) were investigated using the density functional theory (DFT) and crystal morphology theory. The results show that all of the complexes have six-coordinated distorted octahedra, which is different from previous works. This was rationalised by consideration of the intermolecular interactions in the crystal structures. Hence the crystal structure is now more reliable. The chemical reactions of the whole molecule may be triggered by an electron transition of CHZ or ClO-4. Furthermore the energy gaps were observed, and the values of the impact sensitivities were inferred to have the following sequence: [Be(CHZ)3](ClO4)2 > [Mg(CHZ)3](ClO4)2 > [Sr(CHZ)3](ClO4)2 > [Ca(CHZ)3](ClO4)2 > [Ba(CHZ)3](ClO4)2. In addition, the thermodynamic equations at 25-1000 K were obtained. The positive values of the standard molar free enthalpies shows that carbohydrazide perchlorates are stable at 298.15 K. The (1 0 -1) and (0 0 2) faces are the most important growth directions of the crystal morphologies, and have the minimum growth rates. From the cleaved main growth faces, it can be deduced that surface active agents with active hydrogen atoms in the functional groups could be used as crystal-control reagents to control the crystal morphology for alkaline-earth carbohydrazide perchlorates. Source

Zhang X.,Nanjing University of Science and Technology | Pu Y.,Shanxi Applied Physics and Chemistry Research Institute | Hu Z.,Nanjing University of Science and Technology | Chen S.,Nanjing University of Science and Technology | Ling Y.,Nanjing University of Science and Technology
Proceedings of the 2011 2nd International Conference on Digital Manufacturing and Automation, ICDMA 2011 | Year: 2011

A series of sulfonated poly(phenylene arylene) membranes were successfully prepared from 2,5-dichloro-3'-sulfobenzophenone (DCSB) and 2,2′-bis[4-(4- chlorobenzoyl)phenoxyl] perfluoropropane (BCPPF) through Ni(0)-catalyzed copolymerization. The membranes were obtained by solution casting method. They showed good mechanical strength and almost isotropic swelLing behavior. Membrane No.2 with an IEC of 2.0 meg/q showed high polymer electrolyte fuel cell (PEFC) performance data of open cirCuit voltage (OCV) of 0.95 V, cell voltage at 0.5 Acm-2 (V0.5=0.74 V), maximum output (Wmax=0.96 Wcm-2) at 90°C, 80% relative humidity condition. © 2011 IEEE. Source

Lu C.-Y.,Shanxi Applied Physics and Chemistry Research Institute | Sheng D.-L.,Shanxi Applied Physics and Chemistry Research Institute | Chen L.-K.,Shanxi Applied Physics and Chemistry Research Institute | Huo H.,Xian Modern Chemistry Research Institute | And 2 more authors.
Huozhayao Xuebao/Chinese Journal of Explosives and Propellants | Year: 2013

CL-18 with particle size of about 5μm was synthesized via three-step reaction of azide, denitrification cyclization and addition of amino using 1, 3, 5-trinitro-2, 4 -dichlorobenzene as raw material. CL-18 obtained was refined to 1.51μm by a mechanical polishing method, and its specific surface area was 5.237m2/g. The narrow pulse impact initiation performance of ultrafine CL-18 was studied. The results show that the minimum initiation energy of ultrafine CL-18 is less than 0.1331J and 50% initiation voltage is 0.9-1.1kV, which is less than that of HNS-IV under the same conditions. This ultrafine CL-18 is an excellent explosive which is suitable to impact slapper detonator. Source

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