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Preparation of Electrospun Composite PEG/PVP Phase-Change Nanofibers and their Application in Cigarette Cooling Filters

Chen Chen, Li Liqun, Qiao Yuemei, Guo Chunsheng, Ye Yajun, Du He

Fibres & Textiles in Eastern Europe

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2023

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Vol. 31, no. 3

9-13

EN

Composite phase-change nanofibers were prepared by electrospinning with polyethylene glycol (PEG) as the phase-change material (PCM) and polyvinylpyrrolidone (PVP) as the carrier matrix. The high PEG content endowed the nanofibers with an excellent cooling effect and significantly reduced the smoke temperature. For PEG70/PVP nanofibers, the smoke temperature can be decreased 45℃ at the 8th puff, and be kept below 45℃. The cooling test proved that the electrospun PEG/PVP phase-change nanofibers exhibited a desirable cooling performance, improving the comfort of cigarette products. And the composite PEG/PVP phase-change nanofibers present great potential as the cooling cigarette filter material for HnB tobacco application.

2

Characteristics of pure Love mode SAW sensor with graphene interdigital transducer for biosensing applications

Chen Chen, Wang Xinyu, Wang Yuting

Journal of Theoretical and Applied Mechanics

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2022

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Vol. 60 nr 4

551--559

EN

The characteristics of Love wave biosensors are systematically investigated. The results show that sensors with combination of a ZnO guiding layer and 90ST or 90AT Quartz substrates exhibit purer Love modes than those with the SiO2 guiding layer. The corresponding maxi- mum sensitivities are −10.9069 and −11.641m2/kg, respectively, which are nearly two times higher than those of SiO2 layer. The ZnO/90ST Quartz Love wave sensor exhibits the largest K2 of 0.3022 and achieves 0 ppm/oC of TCF at hZnO/λ = 0.0216. The sensor employing the Graphene IDT further improves the sensitivity by nearly one order of magnitude.

3

Multivariate statistical analysis of tropane alkaloids in Anisodus tanguticus (Maxim.) Pascher from different regions to trace geographical origins

Chen Chen, Li Jingjing, Xiong Feng, Wang Bo, Xiao Yuanming, Zhou Guoying

Acta Chromatographica

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2022

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Vol. 34, no. 4

422--429

EN

Anisodus tanguticus (Maxim.) Pascher is an important Tibetan folk medicine and the source of tropane alkaloids (TAs) grown in Qinghai-Tibet Plateau. There are marked differences in quality of A. tanguticus from geographic areas. The aim of present research was to establish a method for the quantitative analysis of TAs coupled with chemometrics analysis to trace geographical origins. Qualitative analysis of TAs in A. tanguticus was carried out using ultra-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry and quantitative analysis of TAs in different plant organs from different geographical origin was achieved. Contents of TAs were subjected to the principal component analysis, and orthogonal partial least-squares discriminant analysis. The contents of the three marker compounds (anisodamine, anisodine and atropine) in the roots and acrial parts of A. tanguticus were positive correlated and varied significantly from different geographical origins. Principal component analysis, and orthogonal partial least-squares discriminant analysis results showed excellent discrimination between different geographical origin of A. tanguticus. This study could provide comprehensive evaluation and further utilization of A. tanguticus resources.

4

Application of MoO3 as an efficient catalyst for wet air oxidation treatment of pharmaceutical wastewater (Experimental and DFT study)

Chen Chen, Cheng Ting, Wang Lei, Tian Yuan, Deng Qin, Shi Yisu

Archives of Environmental Protection

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2021

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Vol. 47, no. 2

47--60

EN

In this work, a highly effective catalyst (MoO3) is synthesized and applied for catalytic wet air oxidation (CWAO) treatment of pharmaceutical wastewater. The catalyst is systematically characterized to investigate the morphology, crystal structure and chemical composition, and the findings demostrated that MoO3 catalyst is successfully synthesized. The degradation mechanism is also illustrated by the density functional theory (DFT) calculation. The degradation experiments confirm that MoO3 catalyst exhibits excellent catalytic performance in CWAO, and the removal rate of TOC (Total Organic Carbon) and COD (Chemical Oxygen Demand) is achieved to more than 93%. The catalyst doses, reaction temperature and reaction time have a significant impact on the removal of pollutants. The degradation process of pollutants in CWAO could be satisfactorily fitted by the second-order kinetics. Besides, MoO3 displays a favorable stability as CWAO catalyst. DFT calculation illustrates that MoO3 catalyst is a typical indirect band gap semiconductor. Moreover, the high temperature environment provides the thermal excitation energy, which favors to the free electrons nearing Fermi level to escape the material surface, and excites them to the conduction band, then directly reduces the pollutants in CWAO. These findings demonstrate that MoO3 can be used as an efficient and excellent catalyst for CWAO of pharmaceutical wastewater.

5

Evaluation of the diference in water quality between urban and suburban rivers based on self organizing map

Jiang Yaqi, Gui Herong, Li Chen, Chen Jiayu, Chen Chen, Wang Chunlei, Zhao Honghai, Guo Yan, Xu Jiying, Li Jun, Qiu Huili

Acta Geophysica

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2021

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Vol. 69, no. 5

1855--1864

EN

Urban rivers play an important role in maintaining the urban aquatic ecological environment, and there are bound to be differences in the water environment quality and pollution sources due to different locations of urban rivers. Therefore, this paper selects the urban river (Tuo River) and the suburban river (Bian River) in Suzhou City, Anhui, China, as the research objects. Based on the understanding of the hydrogeochemical characteristics of these two rivers, the self-organizing map is used to identify the main control factors that affect the water quality of the two rivers. The results showed that both the Bian river and Tuo river were weakly alkaline. The average content of conventional ions in Tuo river is less than that of Bian river (except HCO3 −); the water of Bian river was of Na–SO4–Cl type, and the water of Tuo river was mainly of Na–HCO3 type, with the minority was of Na–SO4–Cl type; Silicate weathering is an important source of conventional ions in the water of these two rivers; agricultural non-point source pollution is the main source of pollutants in Bian river, while Tuo river was mainly affected by natural factors, and human activities had little impact.

6

Surface modification of fly ash spheroidal particles and their application in the adsorption of phosphorus and chromium(VI) from single and competitive solute systems

Chen Chen, Cheng Ting, Zhang Xiao, Zhang Minte, Lv Ruiyang

Environment Protection Engineering

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2020

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Vol. 46, nr 3

39--59

EN

This work focuses on the surface modification of fly ash spheroidal particles and their application in phosphorus and chromium(VI) adsorption. The results show that through surface modification, amorphous silica-alumina gels precipitated on the spheroidal particle surface (by which the microsurface area of the reaction products is effectively enlarged) and the surface zeta potential was changed to fit for adsorbing anions. During the adsorption experiment (single and competitive solute systems), chromium(VI) was easier to adsorb. The surface zeta potential and the existence of competitive ions should be recognized as two important factors affecting adsorption efficiency. A higher temperature could improve the adsorption efficiencies of the two solute systems. The fitting results of the pseudo-second-order model (single and competitive solute systems) show better agreement than those of the pseudo-first-order model at every temperature. The Langmuir adsorption isotherm equation can better simulate the adsorption process in single solute sy039stems, but only the chromium(VI) adsorption process can be fitted by the competitive Langmuir adsorption isotherm in competitive solute systems.

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Efficient separation of five flavonoids from Oxytropis falcata bunge by high-speed counter-current chromatography and their anticancer activity

Chen Chen, Liu Fengqin, Zhao Jingyang, Chen Tao, Li Yulin, Zhang Dejun

Acta Chromatographica

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2020

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Vol. 32, no. 3

189--193

EN

Oxytropis falcata Bunge, known as the “king of herbs” in Tibetan medicine, is used for treatment of hyperpyrexia, pain, wounds, inflammation, and anthrax. However, it is difficult to efficiently isolate compounds with high purity from O. falcata because of the complexity of traditional Tibetan medicines. In this study, the 80% ethanol elution fraction from extract by AB-8 macroporous resin column chromatography was demonstrated to have anticancer activity on human hepatoma SMMC-7721 cells in vitro. Then, a high-speed counter-current chromatography (HSCCC) method was successfully established for separation of compounds by using hexane–ethyl acetate–methanol–water (10:4:10:10, v/v/v/v) as the solvent system. Five flavonoids (7-hydroxyflavonone [1], 5,7-dihydroxy-4′-methoxy flavonol [2], 5,7-dihydroxyflavanone [3], 2′,4′-dihydroxychalcone [4], and 2′,4′-dihydroxydihydrochalcone [5]) were obtained in one-step separation with purities of 97.7%, 98.1%, 98.3%, 99.0%, and 98.3%, respectively. Finally, anticancer activities against the growth of SMMC-7721 cells of 5 flavonoids were confirmed. The IC50 values of the separated compounds were 213.45 μg/mL, 197.74 μg/mL, 375.16 μg/mL, 17.44 μg/mL, and 136.83 μg/mL in 24 h, respectively. The present study provided a basis for further development and utilization of this medicinal herb as a source of a new potential anticancer agent.