Sulfonated polysulfone proton exchange membrane with flexible side chains for fuel cells

Zongwen Qiao,Jiaqi Deng,Tao Chen 한국고분자학회 2024 Macromolecular Research Vol.32 No.2

In this study, chloromethylated polysulfones (CPS) were used as precursors to synthesize two kinds of sulfonated polysulfones with flexible side chains, namely PS-BS (The end of the side chain contains a sulfonic acid group) and PS-BDS (The end of the side chain contains two sulfonic acid groups). This was achieved through nucleophilic substitution reaction using sodium 4-hydroxybenzenesulfonate and disodium 1,2-dihydroxybenzene-3,5-disufonate as nucleophilic reagents, respectively. The chemical structures of the resulting sulfonated polysulfones were characterized using the Fourier infrared spectrum (FT-IR) and nuclear magnetic hydrogen spectrum ( H1-NMR). The proton exchange membranes (PEMs) were fabricated using a solution casting method. Thermogravimetric analysis (TGA) analysis revealed that the obtained PEMs exhibited stability up to 270 °C. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis indicated that PS-BS and PS-BDS PEMs exhibited a clear microphase separation structure, with the hydrophilic sulfonic acid groups located far away from the hydrophobic main chain of PS. This unique structure contributed to improved dimensional stability and oxidative stability of the PEMs. The obtained PEMs show better dimensional stability and oxidative stability. Comparing the two types of PEMs at the same temperature and ion exchange capacity (IEC), PS-BDS PEMs demonstrate better dimensional stability and lower methanol permeability compared to PS-BS PEMs. For instance, PD-BDS-4 PEMs exhibited a dimensional of stability up to 8.6% at room temperature and 30% at 85 °C. The corresponding methanol permeability was 10.29 × 10– 7 cm2/ s at 25 °C, which was significantly lower than that of Nafion112 (10.5 × 10– 7 cm2/ s) PEMs under the same condition.

Self-assembling nanoprobes that display two-dimensional fluorescent signals for identification of surfactants and bacteria

Long, Shuangshuang,Qiao, Qinglong,Deng, Fei,Miao, Lu,Yoon, Juyoung,Xu, Zhaochao The Royal Society of Chemistry 2019 Chemical communications Vol.55 No.7

<P>The imidazolium-pyrene self-assembling nanoprobes can rapidly discriminate four types of surfactants. The surfactants disassembled the probes to turn on significant fluorescence and transform between a pyrene monomer and an excimer, generating a two-dimensional analysis map. The probes were further used to identify different bacterial species.</P>

Moth-Flame Optimization-Based Maximum Power Point Tracking for Photovoltaic Systems Under Partial Shading Conditions

Ji-Ying Shi,Deng-Yu Zhang,Fei Xue,Ya-Jing Li,Wen Qiao,Wen-Jing Yang,Yi-Ming Xu,Ting Yang 전력전자학회 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.5

This paper presents a moth-flame optimization (MFO)-based maximum power point tracking (MPPT) method for photovoltaic (PV) systems. The MFO algorithm is a new optimization method that exhibits satisfactory performance in terms of exploration, exploitation, local optima avoidance, and convergence. Therefore, the MFO algorithm is quite suitable for solving multiple peaks of PV systems under partial shading conditions (PSCs). The proposed MFO-MPPT is compared with four MPPT algorithms, namely the perturb and observe (P&O)-MPPT, incremental conductance (INC)-MPPT, particle swarm optimization (PSO)-MPPT and whale optimization algorithm (WOA)-MPPT. Simulation and experiment results demonstrate that the proposed algorithm can extract the global maximum power point (MPP) with greater tracking speed and accuracy under various conditions.

Moth-Flame Optimization-Based Maximum Power Point Tracking for Photovoltaic Systems Under Partial Shading Conditions

Shi, Ji-Ying,Zhang, Deng-Yu,Xue, Fei,Li, Ya-Jing,Qiao, Wen,Yang, Wen-Jing,Xu, Yi-Ming,Yang, Ting The Korean Institute of Power Electronics 2019 JOURNAL OF POWER ELECTRONICS Vol.19 No.5

This paper presents a moth-flame optimization (MFO)-based maximum power point tracking (MPPT) method for photovoltaic (PV) systems. The MFO algorithm is a new optimization method that exhibits satisfactory performance in terms of exploration, exploitation, local optima avoidance, and convergence. Therefore, the MFO algorithm is quite suitable for solving multiple peaks of PV systems under partial shading conditions (PSCs). The proposed MFO-MPPT is compared with four MPPT algorithms, namely the perturb and observe (P&O)-MPPT, incremental conductance (INC)-MPPT, particle swarm optimization (PSO)-MPPT and whale optimization algorithm (WOA)-MPPT. Simulation and experiment results demonstrate that the proposed algorithm can extract the global maximum power point (MPP) with greater tracking speed and accuracy under various conditions.

miR-124 Inhibits Growth and Invasion of Gastric Cancer by Targeting ROCK1

Hu, Cong-Bing,Li, Qiao-Lin,Hu, Jian-Fei,Zhang, Qiang,Xie, Jian-Ping,Deng, Li Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.16

MicroRNAs (miRNAs) act as critical regulators of genes involved in many biological processes. Aberrant alteration of miRNAs have been found in many cancers, including gastric cancer (GC), but the molecular mechanisms are not well understood. Herein, we investigated the role of miR-124 in GC. We found that its expression was significantly reduced in both GC tissue samples and cell lines. Forced expression of miR-124 suppressed GC cell proliferation, migration, and invasion. Furthermore, the Rho-associated protein kinase (ROCK1) was identified as a direct target of miR-124 in GC cells. Finally, silencing of ROCK1 showed similar effects as miR-124 overexpression, while supplementation of ROCK1 remarkably restored the cell growth and invasion inhibited by miR-124. Together, our data demonstrate that miR-124 acts as a tumor suppressor by targeting ROCK1, and posit miR-124 as a novel strategy for GC treatment.

Adaptive polymorphism of tetrameric alpha-amylase inhibitors in wild emmer wheat

Ji-Rui Wang,Mei Deng,Ya-Xi Liu,Xin Qiao,Zhen-Hong Chen,Qian-Tao Jiang,Zhi-En Pu,Yu-Ming Wei,Eviatar Nevo,You-Liang Zheng 한국유전학회 2011 Genes & Genomics Vol.33 No.4

α-Amylase inhibitors are attractive candidates for the control of seed weevils as these insects are highly dependent on starch as an energy source. Wheat tetrameric α-amylase inhibitor (WTAI) is a mixture (60 kDa) of 3 units: WTAI-CM2 plus 2 WTAI-CM3 plus WTAI-CM16, where none of the subunits is active on its own. A total of 334 gene sequences were obtained from 14 populations (131 accessions= genotypes) of wild emmer wheat. The frequencies of SNPs in WTAI-CM2,WTAI-CM3 and WTAI-CM16 were 1 out of 87.6, 101.4, and 108.0 bases, where 5, 5 and 4 SNPs were detected in the coding sequence, respectively. The nucleotide sequence of each unit of tetrameric α-amylase inhibitors were much more conserved than that of dimeric or monomeric inhibitors. The wild emmer wheat populations showed diversity on three WTAI loci,both between and within populations. It was revealed that WTAI were naturally selected for across populations by a ratio of dN/dS as expected. The results of purifying and positive selection hypothesis (p<0.05) also showed that the sequences of WTAI were contributed by natural selection, which ensures the protein function conservation as well as the inhibition diversity with insects amylase enzyme. Ecological factors, singly or in combination, explained a significant proportion of the variations in the SNPs. Ecological factors have an important evolutionary role in gene differentiation at these loci, and tetrameric α-amylase inhibitors are obviously adaptively selected under different environments.

Gate-tunable current partition in graphene-based topological zero lines

Wang, Ke,Ren, Yafei,Deng, Xinzhou,Yang, Shengyuan A.,Jung, Jeil,Qiao, Zhenhua American Physical Society 2017 Physical Review B Vol.95 No.24

<P>We demonstrate new mechanisms for gate-tunable current partition at topological zero-line intersections in a graphene-based current splitter. Based on numerical calculations of the nonequilibrium Green's functions and Landauer-Buttiker formula, we show that the presence of a perpendicular magnetic field on the order of a few Teslas allows for carrier sign dependent current routing. In the zero-field limit the control on current routing and partition can be achieved within a range of 10-90% of the total incoming current by tuning the carrier density at tilted intersections or by modifying the relative magnitude of the bulk band gaps via gate voltage. We discuss the implications of our findings in the design of topological zero-line networks where finite orbital magnetic moments are expected when the current partition is asymmetric.</P>

Extractive Biodegradation of Diphenyl Ethers in a Cloud Point System: Pollutant Bioavailability Enhancement and Surfactant Recycling

Tao Pan,Chunyan Liu,Qiao Xin,MEI-YING XU,Yangwu Deng,Wei Dong,Shuijing Yu 한국생물공학회 2017 Biotechnology and Bioprocess Engineering Vol.22 No.5

The biodegradation of diphenyl ethers (DEs) in the environment is limited by their high hydrophobicity. The enhancement of DE bioavailability by a cloud point system (CPS) was investigated in this study. Three CPSs (i.e., Triton X-114, Triton X-114 + Triton X-45, and Brij30 + TMN-3) were tested to promote DE biodegradation. Biocompatibility tests showed that the biodegradation of DE and 4-bromodiphenyl ether (4-BDE) was inhibited by TX-114, unaffected by TX-114 + TX-45, and promoted by Brij30 + TMN-3 over 48 h of cultivation with Cupriavidus basilensis and 4% (w/v) nonionic surfactants. Further optimization with 2% (w/v) Brij30 + TMN-3 yielded residual DE and 4-BDE quantities of 143 and 154 mg/L, respectively, lower than quantities in the control. During degradation, DE content did not decrease in the dilute phase, but sharply decreased in the coacervate phase, indicating that the DEs gradually diffused and transferred from the coacervate phase to the dilute phase for degradation by microbial cells. This behavior also enhanced the bioavailability of DEs in the CPS. By removing the cellrich dilute phase and adding fresh degradation medium and DE to the coacervate phase, surfactants were successfully recovered and reused twice without affecting DE biodegradation. Results demonstrated that a CPS with 2% (w/v) Brij30 + TMN-3 not only enhanced the bioavailability of DEs, but also decreased the treatment cost through surfactant recycling, which is beneficial for large-scale applications.

Numerical Analysis and Application on the Parameters Optimization of Open-pit Deep-Hole Bench Loose Blasting

Guang-tao Li,Deng-pan Qiao,Hong-sheng Sun,Li-hua He 보안공학연구지원센터 2016 International Journal of u- and e- Service, Scienc Vol.9 No.12

In order to improve the production efficiency of mine and ensure production safety and aiming at the unsatisfying blasting effects and uneven rock fragments existing in the exploitation blasting and construction process in Manjiazhai stope of Hualian Zinc and Indium Stock company, this paper analyzes and optimizes loosening blasting parameters of Open-pit deep-hole benches based on the blasting mechanism and engineering practical experience of wide hole distance and small resistance lines. Utilizing the numerical simulation of finite element software with ANSYS/LS-DYNA various schemes, analysis validations on the blasting stress field under different parameters are conducted. The simulation results show that: When the holes and rows spacing are 15×9, 16×9, 17×8, the effective stress of discrete cells between blast holes is bigger than the dynamic tensile strength that rocks can be broken. The site experimental investigation is conducted. The blasting effect assessment shows that the control rates of the big size rocks when the holes and rows spacing are 16×9 is 1.904% lower than those when those are 15×9, and 1.079% lower than those are 17×8. And the shovel mucking efficiency and composite economic results are better than that of the other two groups of parameters and confirmed the best blasting parameter design.

Study on Properties of Expansive Soil Improved by Steel Slag Powder and Cement under Freeze-Thaw Cycles

Yankai Wu,Xiaolong Qiao,Xinbao Yu,Jiali Yu,Yongfeng Deng 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.2

Expansive soil is considered to be an unfavorable soil due to its swelling-shrinking behavior. In order to improve the properties of expansive soil, the addition of steel slag powder (SSP) has been used to improve expansive soil that has been mixed with the cement. In this study, a series of cylindrical improved expansive soil specimens were prepared, which were improved either by the addition of cement, cement SSP, or cement SSP sodium hydroxide (NaOH). All of the specimens were prepared with an optimum water content and then subjected to a maximum of 12 closed-system freeze-thaw (F-T) cycles. The specimens were subjected to different curing times and temperatures (-5oC,-10oC and -15oC) during the tests. After each freeze-thaw (F-T) cycle, the volume of each specimen was measured and an unconfined compression strength (UCS) test was performed. The results have shown that as the temperature of the F-T cycle decreased, the volume expansion rate increased with the increase of the length of the F-T cycle. As the curing time increased, the effect of the F-T cycles on the volume change rate of the specimens reduced and the UCS increased. The first F-T cycle had the greatest influence on the volume of the specimen as well as the UCS of the improved expansive soil. After the improved expansive soils had undergone more than eight F-T cycles, the volume change rate of the specimen tended to stabilize. The maximum F-T volume change rate of the improved soil was 1.93%.When the curing age was 60d and 90d, the strength of the specimen with cement SSP sodium hydroxide was 377.3 kPa and 294.7 kPa higher than the specimen with cement only (ES specimen), and its strength degradation rate was 18.737% and 9.97% lower than the ES specimen. The results have shown that the addition of SSP and cement improved the expansive soil; moreover, NaOH inhibited the degradation of the soil during an F-T cycle.