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Search Results: 1 - 10 of 120438 matches for " Tingting Wang "
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On Hom-Lie Pseudo-Superalgebras  [PDF]
Shengxiang Wang, Tingting Tao
Advances in Pure Mathematics (APM) , 2016, DOI: 10.4236/apm.2016.66029
Abstract: The aim of this article is to introduce the notion of Hom-Lie H-pseudo-superalgebras for any Hopf algebra H. This class of algebras is a natural generalization of the Hom-Lie pseudo-algebras as well as a special case of the Hom-Lie superalgebras. We present some construction theorems of Hom-Lie H-pseudo-superalgebras, reformulate the equivalent definition of Hom-Lie H-pseudo-super-algebras, and consider the cohomology theory of Hom-Lie H-pseudo-superalgebras with coefficients in arbitrary Hom-modules as a generalization of Kac’s result.
Stability Evaluation of Surfactant-Grafted Polyacrylamide Used in Oilfields by Evolution of Ammonia  [PDF]
Tingting Jiang, Baohui Wang, Haiyu Wang
Journal of Materials Science and Chemical Engineering (MSCE) , 2014, DOI: 10.4236/msce.2014.25003
Abstract:

Surfactant-grafted Polyacrylamide (S-PAM) serves as a novel oil displacement agent in oilfield. The analysis on composition of S-PAM shows that due to its instability the harmful ammonia gas may be generated during the operation of S-PAM or high temperature. In this paper, stability of S-PAM was studied by measuring the ammonia release from solid and aqueous S-PAM at different temperatures. The results showed that ammonia release of the solid S-PAM was increased with raising temperature. The ammonia release from S-PAM produced by Haibo Company is more than one from Lianhua in the solid state. The ammonia emissions from Lianhua S-PAM are slightly higher than Haibo one in the solutions prepared by both clean water and oilfield water.

Comparative Study of Physical Properties of In-Use Surfactant-Grafted Polyacrylamides for Oilfield  [PDF]
Tingting Jiang, Haiyu Wang, Baohui Wang
Open Journal of Physical Chemistry (OJPC) , 2014, DOI: 10.4236/ojpc.2014.43016
Abstract:

Surfactant-grafted Polyacrylamide (S-PAM), as a new type of oil displacement agent in oilfield, integrates the advantages of both polymer and surfactant. The oil displacement experiments using S-PAM in multi-blocks reveal that in-use S-PAMs differ greatly from ordinary polymers and the physical properties remain unclear. This is unfavorable to production application and occupational health and safety. This research compared the physical properties of S-PAMs selected from two producing area, including specific gravity, particle size and viscosity. The compared results showed that specific gravity of Lianhua S-PAM was smaller than Haibo S-PAM; Lianhua S-PAM and Haibo S-PAM accounted for the 93.8% and 80.1% of the total amount via the particles with 40 mesh and 60 mesh; the viscosity of Lianhua S-PAM was higher than that of Haibo S-PAM in two S-PAM solutions with different concentrations.

The Researches on Exchange Rate Risk of Chinese Commercial Banks Based on Copula-Garch Model  [PDF]
Baoqian Wang, Tingting Cao, Shu Wang
Modern Economy (ME) , 2014, DOI: 10.4236/me.2014.55051
Abstract:

After the exchange rate reforms in 2005, China has transformed the fixed exchange rate system into a floating exchange rate system dominated by market supply and demand. Commercial banks will face with greater exchange rate risk. Therefore, how to estimate exchange rate risk and keep the optimal portfolio of foreign exchange is an important research subject. This article chooses the date of the RMB exchange rate against the dollar and the yen from the January 1, 2008 to May 21, 2012 as samples, describes the joint distribution of the two assets using Copula-Garch model, thus eventually works out the optimal holding ratio of the two foreign currency assets under minimal risk situations.

Chemical Structure of Surfactant-Grafted Polyacrylamide Used in Oilfields  [PDF]
Tingting Jiang, Haiyu Wang, Baohui Wang
Open Journal of Applied Sciences (OJAppS) , 2014, DOI: 10.4236/ojapps.2014.49043
Abstract: Surfactant-grafted Polyacrylamide (S-PAM) flooding is a new technique used in Daqiang Oil Field in China and also a novel way for improving the recovery efficiency of primary oil layer after polymer flooding. S-PAM flooding technology is perfected gradually with the proceeding of multiple polymer surfactant oil displacement tests. Test results showed that the S-PAM used in field was greatly different with conventional ones. Therefore, it is necessary to study the chemical structure of S-PAM. Aiming at making clear the chemical structure of S-PAM, this study characterized the two commonly used S-PAM in oil field through chemical analysis and Fourier infrared spectrometer detection and analyzed the main composition and chemical structure of the two S-PAM.
Analysis and Formation of Hazardous Substances from Surfactant-Grafted Polyacrylamide Powder for Oilfield Production  [PDF]
Tingting Jiang, Haiyu Wang, Baohui Wang
Open Journal of Applied Sciences (OJAppS) , 2014, DOI: 10.4236/ojapps.2014.49047
Abstract: Surfactant-grafted Polyacrylamide (S-PAM) serves as a kind of economical and efficient flooding agents for its single component in the enhanced oil recovery in Daqing oilfield in China. The oil displacement experiments using S-PAM in multi-blocks revealed that in-use S-PAMs differ greatly from ordinary polymers. Aiming at making clear hazardous substances of S-PAM powder, this study characterized two commonly used S-PAMs in oil field through chemical analysis and instrumental analysis, and analyzed the toxic and hazardous gases of the two S-PAM powders.
Sparsity-Based Direct Location Estimation Based on Two-step Dictionary Learning  [PDF]
Tingting Wang, Wei Ke, Gang Liu
Communications and Network (CN) , 2013, DOI: 10.4236/cn.2013.53B2077
Abstract:

This paper proposes an adaptive sparsity-based direct position determination (DPD) appoach to locate multiple targets in the case of time-varying channels. The novel feature of this method is to dynamically adjust both the overcomplete basis and the sparse solution based on a two-step dictionary learning (DL) framework. The method first performs supervised offline DL by using the quadratic programming approach, and then the dictionary is continuously updated in an incremental fashion to adapt to the time-varying channel during the online stage. Furthermore, the method does not need the number of emitters a prior. Simulation results demonstrate the performance of the proposed algorithm on the location estimation accuracy.

                                                                         

Study on Occupational Health and Safety Impact of Surfactant-Grafted Polyacrylamide Used in Oilfields  [PDF]
Tingting Jiang, Baohui Wang, Aijun Wang, Hongjing Han, Hongjun Wu
Occupational Diseases and Environmental Medicine (ODEM) , 2015, DOI: 10.4236/odem.2015.33006
Abstract: Surfactant-grafted Polyacrylamide (S-PAM) serves as a novel oil displacement agent in oilfield. Its toxicity and the impact on the occupational safety are unclear. The analysis on composition and chemical structure of S-PAM shows that due to its instability the harmful ammonia gas may be generated during the operation of S-PAM or high temperature. The toxicity and safety evaluation of the S-PAM were analyzed, and suggestions on the protection were proposed. It can provide a safe and healthy working environment for the operators with enormous social and economic benefits.
Optima of Trypsin-Catalyzed Hydrolysis and Its Inhibition Determined by SDS-PAGE  [PDF]
Xueke Zhou, Tingting Wang, Anjun Wang, Renqiang Li
Advances in Enzyme Research (AER) , 2016, DOI: 10.4236/aer.2016.41001
Abstract: SDS-PAGE was applied to determine trypsin activity and inhibition. After the hydrolysis by trypsin to substrate bovine serum albulnin (BSA) under different temperatures and pH, the hydrolysis degree of BSA was conducted using SDS-PAGE. From the quantitative analysis to the electrophoresis bands of BSA and its hydrolysis products in SDS-PAGE pattern, the change of trypsin activity was determined, and then the optimum temperature at 40°C and the optimum pH at pH 8.5 - 8.7 for trypsin activity were obtained. All the target bonds in BSA molecule could be hydrolyzed at the same time by trypsin. The inhibition was due to the binding of inhibitor to trypsin, which made it impossible for trypsin to touch the substrate protein. SDS-PAGE was demonstrated to be also an effect method for assaying the characteristics of trypsin activity and its inhibition.
Some Properties of Solutions to a Class of Dirichlet Boundary Value Problems
Tingting Wang,Gejun Bao
Abstract and Applied Analysis , 2012, DOI: 10.1155/2012/268612
Abstract:
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