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Lanzhou, China

Wang T.-P.,Lanzhou Jiaotong University | Wang L.-B.,Lanzhou Jiaotong University | Li B.-Q.,Lanzhou City University
Energy and Buildings | Year: 2013

Considering convection heat transfer between inside and outside surfaces of the glazing and conduction heat transfer of glass sheet, this paper presents a mathematical model of the long-wave radiation heat transfer between inside room surfaces and outside environmental surface through a glazing. The effects of three main factors on the overall heat flux are evaluated. Three main factors are the glass transmittance of long-wave radiation, convection heat transfer coefficient of inside and outside glass surface, the difference between the inside room surface temperature and the indoor air temperature as well as the difference between the outside environmental surface temperature and the outdoor air temperature. If the long-wave radiation transmittance approaches to 0.1, the effects of the transparence radiation of glass or some polymer material on the overall heat flux are obvious and cannot be ignored. The effects of convection heat transfer coefficient of inside and outside glass surface on the overall heat flux are relatively weak. If the temperature difference between the surface and air temperature is less than 2 °C, the effects on the overall heat flux and the role of the transparence radiation are weak. But if the difference is large, the effects are obvious and significant. © 2013 Elsevier B.V. Source

Zhang W.,Jiangnan University | Jiang P.,Jiangnan University | Wang Y.,Jiangnan University | Zhang J.,Lanzhou City University | Zhang P.,Jiangnan University
Catalysis Science and Technology | Year: 2015

Two kinds of novel functional covalent organic frameworks were assembled with the porphyrin building block and terephthalaldehyde or squaric acid via bottom-up approach. Here, our reported covalent porphyrinic frameworks with coordinated manganese(iii) ions (Mn-CPF-1 and Mn-CPF-2) present promising catalytic properties for the selective oxidation of olefins. © The Royal Society of Chemistry 2015. Source

Peng H.,Northwest Normal University | Ma G.,Northwest Normal University | Mu J.,Northwest Normal University | Sun K.,Lanzhou City University | Lei Z.,Northwest Normal University
Journal of Materials Chemistry A | Year: 2014

Asymmetric supercapacitors (ASCs) with high energy density are assembled based on the pseudocapacitance of both electrodes, which use polyaniline (PANI) nanotubes as positive electrodes and MoO3 nanobelts as negative electrodes in a 1 M H2SO4 aqueous electrolyte. The assembled novel PANI//MoO3 ASC device with an extended operating voltage window of 2.0 V, in spite of the use of an aqueous electrolyte, exhibits excellent performance such as a high specific capacitance of 518 F g -1 at a current density of 0.5 A g-1, reaching an energy density as high as 71.9 W h kg-1 at a power density of 254 W kg -1 and good cycling stability. © 2014 the Partner Organisations. Source

We have developed a supercapacitor electrode composed of CuS microspheres with polypyrrole (PPy) uniformly inserted into the sheet-like subunit structure and coated onto the CuS surface to enhance the pseudocapacitive performance. Novel sphere-like CuS particles with intertwined sheet-like subunit structure are fabricated by a solvothermal approach without any surfactant or template. A CuS@PPy composite electrode is prepared by in situ oxidation polymerization of pyrrole in the presence of the CuS suspension. The CuS@PPy composite (CuS content is 16.7 wt%) exhibits a high specific capacitance of 427 F g -1 (at 1 A g-1) and its capacitance can still retain 88% after 1000 cycles. © The Royal Society of Chemistry. Source

Tong C.,Lanzhou City University
IOP Conference Series: Materials Science and Engineering | Year: 2015

A experiment plan was designed according to the working conditions of sucker rod and the requirements for pump depth in 3000 m in the oil field, the tensile strength for 6K T300 under a normal temperature and high temperature was measured by using universal testing machine, and then, the resistance to corrosion for a crude oil was verified by measuring the tensile strength for 6K T300 after crude oil immersion at a certain time, and the conclusions are that the material is sensitive relatively to corrosion of crude oil and that the tensile strength of the 6K T300 compared with similar products is lower, a proposal to the GH company that to meet the need of oil field production instead of the rigid rod the tensile strength and corrosion resistant for a crude of the T300 6 k materials have to do further efforts was pointed out. Source

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