A Tower-Shaped Three-Dimensional Piezoelectric Energy Harvester for Low-Level and Low-Frequency Vibration

Xiaoxiang Wei,Haibo Zhao,Junjie Yu,Yiming Zhong,Yanlin Liao,Shiwei Shi,Peihong Wang 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.8 No.5

The multiple forms of vibration exist in an ambient environment diffusely and already become a considerable object for energy harvesting. However, how to effectively extract low-level, low-frequency, and multi-directional vibration from the ambient environment is becoming a key issue in the field of energy harvesting. To solve this issue, a tower-shaped piezoelectric vibration energy harvester (TS-PVEH) is reported. Finite element simulation indicates that TS-PVEH works in two fundamental modes, i.e., its in-plane and out-of-plane vibration modes. Meanwhile, simulation results show that the natural frequency of TS-PVEH is 3.39 Hz, 3.40 Hz, and 11.50 Hz, respectively; and the experiments also verified that. By virtue of the tower structure of TS-PVEH, the device is pretty sensitive to three-dimensional vibration. At a low level of acceleration 1 m/s 2 , the maximum load power of TS-PVEH is 65.8 μW in out-of-plane mode and 17.2 μW in in-plane mode, respectively. Furthermore, the effects of the PVDF connection mode on the output performance of TS-PVEH were studied in detail, and comparative experimental results show that a reasonable connection of PVDF can improve energy harvesting efficiency. The proposed TS-PVEH is expected to be used to scavenge energy from multi-dimensional, low-level, and low-frequency vibrations that present in an ambient environment.

Transesterification of soybean oil to biodiesel by tin-based Brønsted-Lewis acidic ionic liquid catalysts

Xiaoxiang Han,Shang-Bin Liu,Wei Yan,Chin-Te Hung,Yanfei He,Pei-Hao Wu,Li-Li Liu,Shing-Jong Huang 한국화학공학회 2016 Korean Journal of Chemical Engineering Vol.33 No.7

A series of Brønsted-Lewis acidic ionic liquid (BLAIL) catalysts consisting of sulfonated ionic liquid [SO3H-pmim]Cl and Sn(II) chloride have been synthesized and exploited for catalytic transesterification of soybean oil with methanol to biodiesel. The structural and chemical properties of these [SO3H-pmim]Cl-xSnCl2 (x=0-0.8) catalysts were characterized by different analytical and spectroscopic techniques, such as FT-IR, TGA, and NMR. In particular, their acid properties were studied by solid-state 31P NMR using trimethylphosphine oxide as the probe molecule. The BLAIL catalysts were found highly efficient for transesterification reaction due to the introduction of Lewis acidity by SnCl2 in the initially Brønsted acidic [SO3H-pmim]Cl catalyst. The effects of three independent process variables on biodiesel yield were optimized by response surface methodology (RSM). Consequently, an excellent biodiesel yield of 98.6% was achieved under optimized reaction conditions over the BLAIL catalyst with SnCl2 loading (x) of 0.7.

Synthesis of novel Brønsted–Lewis acidic ionic liquid catalysts and their catalytic activities in acetalization

Yan Wei,Han Xiaoxiang,Chen Keke,Zhang Xiaofang,Kuang Yingying,Tang Xiujuan 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.29 No.-

Ionic liquid catalysts which combine the characters of the Brønsted–Lewis solid acids and the ionic liquidare prepared. The obtained composite materials were well characterized by FT-IR, TGA, 1H NMR, 13CNMR and investigated their performance for acetalization. The acid strength was determined by theHammett method combined with UV–vis spectroscopy. Response surface methodology (RSM) wasapplied to optimize the synthesis of benzaldehyde glycol acetal and the effects of various reactionconditions. A Box–Behnken experimental Design (BBD) was employed to search for the optimal yield. The kinetic study for the acetalization was performed under the optimum operating conditions

Removal of direct dyes by coagulation: Adaptability and mechanism related to the molecular structure

Qunshan Wei,Yanxia Zhang,Josphat Igadwa Mwasiagi,Xiaoxiang Zhao,Christopher W. K. Chow,Rui Tang 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.7

The textile industry uses a variety of synthetic dyes for dyeing and discharges a large amount of coloredwastewater. It is difficult to achieve good decolorization effect for textile wastewater by conventional biological treatmentmethods, because it contains various synthetic dyes with complex structures. At present, coagulation is an economicaland effective treatment method. However, in dye removal by coagulation research, the adaptability and mechanismsof coagulation removal of many dyes are still unknown due to the wide variety of dyes in use. In this study, ferricchloride (FeCl3), aluminum chloride (AlCl3) and magnesium chloride (MgCl2) were selected as coagulants, anddirect orange 26 (DO), direct yellow 11 (DY) and direct black 19 (DB) were used as the dye samples to conduct aseries of coagulation experiments; in order to understand the coagulation adaptability and mechanism for high removalefficiency of direct dyes. In this system without particles, the direct dyes were dissolved directly in pure water andmaintained in molecular state. The results showed that 1) AlCl3, FeCl3 and MgCl2 exhibited superior coagulation efficiencyon the three dyes. Direct dyes which contain more amino functional groups are more easily removed by coagulation. 2) The influence of hydraulic conditions on the residual turbidity was more significant compared with the colorremoval. 3) Zeta potential increased with the increase of the coagulant dosage, but the colloidal particles did not re-stabilize. This proved that charge neutralization is not the dominant mechanism of coagulation. The FT-IR and XRD patternsindicated that the direct dyes were removed by the chemical combination of the -SO3H on the dye molecule andthe hydrolysate of the coagulant.

TAp73 and ΔNp73 Have Opposing Roles in 5-aza-2'-Deoxycytidine-Induced Apoptosis in Breast Cancer Cells

Lai, Jing,Yang, Fang,Zhang, Wenwen,Wang, Yanru,Xu, Jing,Song, Wei,Huang, Guichun,Gu, Jun,Guan, Xiaoxiang Korean Society for Molecular and Cellular Biology 2014 Molecules and cells Vol.37 No.8

The p73 gene contains an extrinsic P1 promoter and an intrinsic P2 promoter, controlling the transcription of the pro-apoptotic TAp73 isoform and the anti-apoptotic ${\Delta}Np73$ isoform, respectively. The DNA methylation status of both promoters act equally in the epigenetic transcriptional regulation of their relevant isoforms. The aim of this study was to analyze the different effects of these p73 isoforms in 5-aza-2'-deoxycytidine (5-aza-dC)-induced apoptosis in breast cancer cells. We investigated the effects of the DNA demethylation agent, 5-aza-dC, on the T-47D breast cancer cell line, and evaluated the methylation status of the p73 promoters and expression of TAp73 and ${\Delta}Np73$. Furthermore, we assessed the expression of p53 and p73 isoforms in 5-aza-dC-treated T-47D cells and p53 knockout cells. 5-aza-dC induced significant anti-tumor effects in T-47D cells, including inhibition of cell viability, G1 phase arrest and apoptosis. This was associated with p73 promoter demethylation and a concomitant increase in TAp73 mRNA and protein expression. In contrast, the methylation status of promoter P2 was not associated with ${\Delta}Np73$ mRNA or protein levels. Furthermore, demethylation of P2 failed to inhibit the expression of ${\Delta}Np73$ with 5-aza-dC in the p53 knockdown cell model. Our study suggests that demethylation of the P1 and P2 promoters has opposite effects on the expression of p73 isoforms, namely up-regulation of TAp73 and down-regulation of ${\Delta}Np73$. We also demonstrate that p53 likely contributes to 5-aza-dC-induced ${\Delta}Np73$ transcriptional inactivation in breast cancer cells.

TAp73 and ΔNp73 Have Opposing Roles in 5-aza-2'-Deoxycytidine-Induced Apoptosis in Breast Cancer Cells

Jing Lai,Fang Yang,Wenwen Zhang,Yanru Wang,Jing Xu,Wei Song,Guichun Huang,Jun Gu,Xiaoxiang Guan 한국분자세포생물학회 2014 Molecules and cells Vol.37 No.8

The p73 gene contains an extrinsic P1 promoter and an intrinsic P2 promoter, controlling the transcription of the pro-apoptotic TAp73 isoform and the anti-apoptotic ΔΝp73 isoform, respectively. The DNA methylation status of both promoters act equally in the epigenetic transcriptional regulation of their relevant isoforms. The aim of this study was to analyze the different effects of these p73 isoforms in 5-aza-2'-deoxycytidine (5-aza-dC)-induced apoptosis in breast cancer cells. We investigated the effects of the DNA demethylation agent, 5-aza-dC, on the T-47D breast cancer cell line, and evaluated the methylation status of the p73 promoters and expression of TAp73 and ΔNp73. Furthermore, we assessed the expression of p53 and p73 isoforms in 5-aza-dC-treated T-47D cells and p53 knockout cells. 5-aza-dC induced significant anti-tumor effects in T-47D cells, including inhibition of cell viability, G1 phase arrest and apoptosis. This was associated with p73 promoter demethylation and a concomitant increase in TAp73 mRNA and protein expression. In contrast, the methylation status of promoter P2 was not associated with ΔNp73 mRNA or protein levels. Furthermore, demethylation of P2 failed to inhibit the expression of ΔNp73 with 5-aza-dC in the p53 knockdown cell model. Our study suggests that demethylation of the P1 and P2 promoters has opposite effects on the expression of p73 isoforms, namely up-regulation of TAp73 and down-regulation of ΔΝp73. We also demonstrate that p53 likely contributes to 5-aza-dC-induced ΔNp73 transcriptional inactivation in breast cancer cells.