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Zhang F.,Zhengzhou University | Wei H.,Zhengzhou University | Dou X.,China Pingmei Shenma Group | Wang X.,Zhengzhou University
Petroleum Processing and Petrochemicals | Year: 2015

Silicalite-1 was synthesized by hydrothermal method. The catalytic performance of Silicalite-1 treated by different calcination temperatures in vapor phase Beckmann rearrangement of cyclohexanone oxime was investigated. Silicalite-1 catalysts were characterized by XRD, IR, BET and thermal analysis. The results show that the calcination temperature has an important effect on the conversion of cyclohexanone oxime and the stability of the Silicalite-1 catalyst, but no obvious influence on the selectivity of caprolactam. With the increase of calcination temperature, BET surface area of molecular sieve does not change significantly, while external surface area first increases and then decreases. The ratio of micropore volume to the total volume is on the decline. The Silicalite-1 calcinated at 400 °C exhibits an excellent activity and stability in vapor phase Beckmann rearrangement reaction. Source

Lu T.-K.,Henan Polytechnic University | Yao Z.-F.,Henan Polytechnic University | Chang F.-T.,Henan Polytechnic University | Zhao Z.-J.,China Pingmei Shenma Group
Journal of Coal Science and Engineering | Year: 2012

The paper discussed a comprehensive numerical simulation and field work by the usage of waterjet slotting technique to prevent the occurrence of outbursts in soft and outburst prone coal seams. This was based on the geological and geomechanical conditions of Jinjiachong Colliery, Guizhou Province, associated with varied waterjet slotting parameters such as slotting penetration, slotting thickness and slotting distance along the length of borehole. Also, to understand the variation of internal stress of coal seams after waterjet slotting application, the internal stress levels were compared with and without slotting application, and the results indicate that the internal effective stress levels can be reduced to 70% and 45% for the vertical and horizontal stresses, respectively, and the gas concentration can be increased up to 5 times when the waterjet slotting is applied. © 2012 The Editorial Office of Journal of Coal Science and Engineering (China) and Springer-Verlag Berlin Heidelberg. Source

Hu J.,Henan University of Urban Construction | Liao C.,Henan University of Urban Construction | Chen S.,Henan University of Urban Construction | Jin P.,China Pingmei Shenma Group | And 2 more authors.
Inorganic Chemistry Communications | Year: 2014

To pursuit the subtle influence exerted on the structure by the anions, two new complexes, namely [Ag(pbmb)·SO3CF3] n 1, and [Ag(pbmb)·ClO4]n 2 have been constructed by the reaction of a V-shaped flexible ligand 1-((2-(pyridin-2-yl)- 1H-benzoimidazol-1-yl)methyl)-1H-benzotriazole (pbmb) and corresponding silver salts under solvothermal conditions. Single crystal analysis shows that the binuclear-based 1 and 2 are 1D motifs with different structural features, especially for complex 1 with the shortest Ag***Ag distance of 2.928 Å. Both complex 1 and 2 exhibit rich luminescent behaviors at temperatures 10-298 K, whereas complex 1 manifests stronger phosphorescence by comparison with 2. © 2014 Elsevier B.V. Source

Li K.,China University of Geosciences | Li K.,Stanford University | Gao Y.,Petroleum Exploration and Production Research Institute | Lyu Y.,Sinopec | Wang M.,China Pingmei Shenma Group
SPE Journal | Year: 2015

Proppant embedment plays a significant role in decreasing fracture aperture and conductivity, especially for weakly consolidated sandstones, shale (oil and gas) rock, and coalbeds. Empirical and semiempirical models were usually used to calculate the embedment of proppants. However, the accuracy of matching or predicting the proppant embedment with these existing models may not be satisfactory in some cases. On the other hand, it is difficult to determine the coefficients of these models. In this study, analytical models were derived to compute proppant embedment and fracture conductivity. One can use these new models to calculate the proppant embedment, proppant deformation, the change in fracture aperture, and fracture conductivity in the ideal or experimental situations of either single-layer or multilayer patterns in the fractures under closure pressures. The new models showed that the proppant embedment and fracture conductivity are affected by the factors, for example, of closure pressure, fracture aperture, the elastic modulus of proppant and coalbed, the size of proppant, and the concentration of proppant-paving. Experimental data of proppant embedment in fractures and fracture conductivity of different proppants at different closure pressures were used to test the models derived in this study. The results from matching the experimental data with the new and the existing models were compared. The results showed that the new models, especially the revised new models, could match the experimental data in all the cases studied. The new models for calculating the proppant embedment and fracture conductivity with a better accuracy are of great significance in selecting proppants, which is helpful to achieve high fracture conductivity and then high oil or gas production of conventional and (especially) unconventional resources such as shale oil, shale gas, and coalbed methane. Copyright © 2015 Society of Petroleum Engineers. Source

Sha B.,Henan Academy of science | Wang J.,Henan Academy of science | Zhou L.,China Pingmei Shenma Group | Zhang X.,Henan Academy of science | And 3 more authors.
Journal of Applied Polymer Science | Year: 2013

In this study, hexamethylenediamine (HMD) and hexamethyleneimine (HMI) were removed from a real wastewater by carboxyl group-modified polyacrylonitrile (RPFC-I) fibers. Adsorption of organic amines by fibrous absorbents is a new technique. Adsorption by fibers has advantages of fast kinetic, high adsorption capacity, and efficiency. Moreover, the fibers could be repeatedly used after regeneration. Batch adsorption tests were conducted to investigate adsorption comparison of the three fibers, adsorption kinetic, adsorption isotherms, regeneration, and readsorption stability. The experiments showed that RPFC-I fibers had excellent adsorption capacity for HMI and HMD. The adsorption equilibrium was achieved very fast within about 5 min, and the removal rate of total nitrogen (TN) was above 99%. The adsorption kinetic could be well fitted by the pseudo-second-order equation. And the adsorption isotherm could be well fitted by the Langmuir model. The estimated maximum adsorption capacity was 105.2 mg g-1, nearly similar with cation exchange capacity (CEC) of RPFC-I fibers. Results from adsorption stability tests demonstrated that the RPFC-I fibers could be fully regenerated by HCl and the regenerated fibers could be repeatedly used even after 12 adsorption-desorption cycles. Analyses from Fourier transform infrared and the adsorption tests suggested that chemical reaction between carboxyl groups and organic amines was the main mechanism for removal of HMI and HMD from the wastewater. The RPFC-I fibers prepared in the current study have a wide application in wastewater treatment and useful substance recovery. © 2012 Wiley Periodicals, Inc. Source

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