Publications by authors named "Wenqing Du"

3 Publications

  • Page 1 of 1

Preparation and Properties of a Composite Phase Change Energy Storage Gypsum Board Based on Capric Acid-Paraffin/Expanded Graphite.

ACS Omega 2021 Mar 25;6(9):6144-6152. Epub 2021 Feb 25.

The Laboratory of Architectural Environment and Energy Application Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, Jiangxi Province, China.

Energy has become the key material basis of social development. In this work, liquid capric acid-paraffin was evenly adsorbed in the pore structure of expanded graphite (EG) by a physical adsorption method, and the new composite phase change material of capric acid-paraffin/expanded graphite (CA-P/EG) was prepared. The Fourier transform infrared (FT-IR) curves of CA-P/EG composites did not change after 1000 cycles, and there was no new characteristic absorption peak, indicating that CA-P/EG composites have good chemical stability. The results showed that the optimum content of CA-P/EG in a phase change energy storage gypsum board was 20%, and the wet bending strength and compressive strength were 2.42 and 6.45 MPa, respectively. The water absorption was 16.37%, and the apparent density was 1.410 g/cm. In addition, the melting and freezing temperatures were 26.40 and 23.10 °C, and the latent heats of melting and freezing were 27.20 and 25.69 J/g, respectively. It was found that the gypsum board has excellent thermal stability after 400 times of melting-freezing cycling and that the heat storage capacity increases with the increase of the CA-P/EG content and the thickness of the gypsum board.
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http://dx.doi.org/10.1021/acsomega.0c05058DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7948235PMC
March 2021

Study of Phase-Transition Characteristics of New Composite Phase Change Materials of Capric Acid-Palmitic Acid/Expanded Graphite.

ACS Omega 2020 Oct 13;5(42):27522-27529. Epub 2020 Oct 13.

The Laboratory of Architectural Environment and Energy Application Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, Jiangxi, China.

A new composite phase change material of capric acid-palmitic acid/expanded graphite (CA-PA/EG) with the optimum mass ratio of EG equated to 8:1 was prepared by the physical adsorption method. It was observed that the eutectic point of CA-PA binary system was reached at 22.1 °C, and CA-PA was uniformly distributed into the pores of EG by physical interaction. The melting and freezing temperatures of CA-PA/EG obtained by differential scanning calorimeter (DSC) were 23.05 and 20.82 °C, respectively, while the corresponding latent heats were 139.7 and 131.8 J/g, respectively. It had good thermal and chemical stability, and there was almost no leakage of liquid binary phase change materials after 1000 melting-freezing cycles. According to the experimental results of the thermogravimetry (TG) analyzer as well as heat storage and release, CA-PA/EG has excellent thermal reliability and heat resistance and the high thermal conductivity of EG promotes the thermal energy storage and release rate of CA-PA. Thus, CA-PA/EG is suitable as a phase change energy storage material for building energy conservation.
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http://dx.doi.org/10.1021/acsomega.0c03665DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7594160PMC
October 2020

Comparison of different extraction methods for polysaccharides from Crataegus pinnatifida Bunge.

Int J Biol Macromol 2020 May 9;150:1011-1019. Epub 2019 Nov 9.

Jiangsu Key Laboratory of Regional Resource Exploitation and Medicinal Research, Huaiyin Institute of Technology, Huai'an 223003, PR China. Electronic address:

In this study, different extraction methods of polysaccharides from Crataegus pinnatifida Bunge (CPP) were compared by studying the extraction yield, structural characteristics and antioxidant activities. Firstly, polysaccharides were obtained using hot water extraction (CPPh), ultrasound assisted extraction (CPPu), enzyme assisted extraction (CPPe) and enzyme-ultrasound assisted extraction (CPPc), respectively. Meanwhile, the optimum extraction conditions of enzyme-ultrasonic assisted extraction were determined by response surface method (RSM). The extraction yields, structural characteristics and antioxidant activities were investigated and compared by visual photos, gas chromatography, ultraviolet-visible and Fourier-transform infrared spectroscopy. The results clearly showed that enzyme-ultrasonic assisted extraction possessed the highest extraction yield (10.39 ± 0.04%). The molecular weight of CPPh was the highest while the other polysaccharides had no significant difference. Besides, the monosaccharide composition of CPPc, CPPh, CPPu and CPPe were similar but the molar percentages of monosaccharide were different. Finally, the results of antioxidant activities showed that CPPc exhibited the highest scavenging effect of superoxide radical and lipids inhibiting ability. In summary, enzyme-ultrasonic assisted extraction was a high-efficient and low-energy consumption method for CPP extraction.
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http://dx.doi.org/10.1016/j.ijbiomac.2019.11.056DOI Listing
May 2020
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