Integrating magnetized bentonite and pinecone-like BiOBr/BiOI Step-scheme heterojunctions as novel recyclable photocatalyst for efficient antibiotic degradation

Guofu Huang,Kun Liu,Yaseen Muhammad,Tian Fu,Linxing Wang,Jiajing Nong,Shiqi Xu,Luying Jiang,Zhangfa Tong,Hanbing Zhang 한국공업화학회 2023 Journal of Industrial and Engineering Chemistry Vol.122 No.-

Utilizing the cost-effective natural clay and surface heterojunction engineering to synergistically constructan efficient heterojunction system and promote the separation of photogenerated charges is anappealing strategy for achieving superior photocatalytic activity. In this study, BiOBr/BiOI step-scheme(S-scheme) heterojunction in-suit grown on magnetized bentonite (MBT) was first engineered via facileand mild coprecipitation coupling microwave solvothermal process. The optimized magnetic bentonite/BiOBr/BiOI (MBT25/BiOBr/BiOI, the mass ratio of MBT to BiOBr/BiOI was 25%) attained the largest reactionrate constant (k = 0.021 min1) in tetracycline (TC) photocatalytic degradation within 80 min visible-lightirradiation. In addition, the reaction rate constant k of MBT25/BiOBr/BiOI for TC degradation was 10.51folds higher than that of pristine BiOI. Significantly, the characterization results demonstrated thatMBT effectively assisted the pinecone-like morphology formation of BiOBr/BiOI and endowed the wonderfulmagnetic-separation ability for MBT25/BiOBr/BiOI. Additionally, MBT ingeniously introduced atthe interface could couple with S-scheme heterojunction between BiOBr and BiOI to synergistically boostthe separation and transfer of photogenerated charges. As expected, superior photochemical propertiesand efficient production of active species over MBT25/BiOBr/BiOI were confirmed. Notably, recyclingexperiments verified the wonderful photocatalytic stability and high recovery efficiency of MBT25/BiOBr/BiOI. Furthermore, the abundant O2and OH active species led to hydroxylation, dealkylation,deamidation and ring opening of TC molecules. A synergistically enhanced mechanism over S-schemeMBT25/BiOBr/BiOI was clarified based on band structure calculations. This study offers an innovative perspectiveto design multifunctional photocatalysts with superior activity by integrating properties of magnetizedclay and S-scheme heterojunction.

Exogenous Spermidine Improves Chilling Tolerance in Sweet Corn Seedlings by Regulation on Abscisic Acid, ROS and Ca2+ Pathways

Cai Shuyu,Wang Guofu,Xu Hua,Liu Jianxin,Luo Jie,Shen Yi 한국식물학회 2021 Journal of Plant Biology Vol.64 No.6

Chilling stress is a major abiotic constraint that affects sweet corn seedling establishment. Spermidine (Spd) is known to participate in the cold stress response in plants, nonetheless, the molecular mechanisms are largely unknown. The present study reported that exogenous Spd not only stimulated seedling growth but also enhanced photosynthetic attributes under chilling stress. Further analysis revealed that Spd application resulted in depressed abscisic acid (ABA) content and affected the expression of ABA-responsive genes. The augmented antioxidant enzymes activities, coupled with declined reactive oxygen species (ROS) content, were observed in response to Spd treatment under chilling stress. Moreover, Spd up-regulated the transcription levels of some Ca2+ transport-related genes. We propose that Spd contributes to cold tolerance in sweet corn seedlings via the regulation of genes involved in the ROS, ABA pathways and Ca2+ transport.

Identification method of nonlinear maneuver model for unmanned surface vehicle from sea trial data based on support vector machine

Gongxing Wu,Jiawei Zhang,Guofu Li,Linling Wang,Qiang Yu,Jiamin Guo 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.8

In order to solve the difficulty of modeling the unmanned surface vehicle (USV) nonlinear maneuver model, a combination identification method of linear hydrodynamic coefficients and nonlinear hydrodynamic coefficients based on support vector machine (SVM) is proposed. The identification principle of USV hydrodynamic coefficients is briefly introduced and a regression algorithm of the SVM is derived for the USV maneuver model. Then, the linear hydrodynamic coefficients of the hull are identified by using a series of USV turning test data at small water-jet angles. And the large water-jet angle turning motion test data and the identified linear hydrodynamic coefficients are used to identify the nonlinear hydrodynamic coefficients for USV. The fourth-order Runge-Kutta method is used to design the USV maneuver simulation program, and a series of USV turning motion simulation experiments are carried out. The simulation data is compared with the corresponding USV sea trial data. Through comparative analysis, it is shown that the USV maneuver mathematical model established in this paper can describe the maneuverability of the USV. It is feasible to use the combination method of SVM to identify the hydrodynamic coefficient of USV.

Enhanced Antibacterial Effect of Polypyrazole-Graphene Oxide Composite

Bin Yang,Yufei Wang,Longqiang Xiao,Xiaowen Hu,Guofu Zhou 한국고분자학회 2017 Macromolecular Research Vol.25 No.1

Besides excellent physical performances, graphene oxide (GO) has been widely acknowledged as a potential antibacterial material. Chemical modification of GO was taken out with polypyrazole by facile amidation in the presence of dicyclohexylcarbodiimide (DCC) and then generated polypyrazole-graphene oxide (FGO) nanohybrid. FGO nanohybrid showed smooth and multilayer structures by scanning electron microscopy. The value of static water contact angle of FGO is 103o, suggesting FGO was a hydrophobic material. Thermo gravimetric analysis of FGO showed a 65% mass loss up 50 to 600 oC, suggesting that FGO is a thermal stability material. Inactivation efficiency test of nominal Escherichia coli cells showed that the viability greatly decreased to 7% after 4 h incubation with FGO under 37 oC, indicating an outstanding antibacterial ability of FGO much better than that of polypyrazole and GO.

Improved Received Signal Strength Ratio Based High Accuracy Indoor Visible Light Positioning Scheme

Zhijie Luo,JinHua Wang,WenWen Zhao,JianKun Luo,WeiNan Zhang,GuoFu Zhou 보안공학연구지원센터 2016 International Journal of Smart Home Vol.10 No.12

With the increasingly development of Light-emitting Diode (LED) lighting, in this paper, we proposed an Indoor Visible Light Positioning (VLP) Scheme by using visible LED lights for accurate localization. The basic idea of the position scheme is to improve received signal strength ratio algorithm. Received signal strength ratio (RSSR) is the relative ratio of optical powers detected between each LED and optical receiver. In this paper, we introduce concept of multiple LEDs selection to improve RSSR positioning algorithm. By three LEDs are reasonably selected from the multiple LEDs deployed in the room, the positioning accuracy of RSSR is improved. The system can be employed easily because it does not require additional sensors and occlusion problem in visible light would be alleviated. In addition, we performed the simulation experiments, and confirmed the feasibility of our proposed method.

An Approximate Calculation Model for Electromagnetic Devices Based on a User-Defined Interpolating Function

Ye Xuerong,Deng Jie,Wang Yingqi,Zhai Guofu 한국자기학회 2014 Journal of Magnetics Vol.19 No.4

Optimization design and robust design are significant measures for improving the performance and reliability of electromagnetic devices (EMDs, specifically refer to relays, contactors in this paper). However, the implementation of the above-mentioned design requires substantial calculation; consequently, on the premise of guaranteeing precision, how to improve the calculation speed is a problem that needs to be solved. This paper proposes a new method for establishing an approximate model for the EMD. It builds a relationship between the input and output of the EMD with different coil voltages and air gaps, by using a user-defined interpolating function. The coefficient of the fitting function is determined based on a quantum particle swarm optimization (QPSO) method. The effectiveness of the method proposed in this paper is verified by the electromagnetic force calculation results of an electromagnetic relay with permanent magnet.

Lewis acid-catalyzed transesterification and esterification of high free fatty acid oil in subcritical methanol

Xianglin Hou,Yongqin Qi,Xingang Qiao,Guofu Wang,Zhangfeng Qin,Jianguo Wang 한국화학공학회 2007 Korean Journal of Chemical Engineering Vol.24 No.2

acid catalysts are active for both esterification and transesterification, but the reaction is very slowdue to mass-transfer limitations betwen methanol and oil phase. Because oil, FFA and Lewis acid catalysts are allsoluble in the subcritical methanol phase, the esterification and transesterification will be enhanced when they are carriedout under subcritical conditions. In this work, the esterification and transesterification of high FFA oil to biodiesel viaLewis acid catalysts such as Pb(OOCH3)2, Cd(OOCCH3)2 and Zn(OOCCH3)2 were carried out in the subcritical meth-anol phase (2 MPa, 180oC, reaction time 30 min). The results show that the esterification conversion reaches 79.8-96.4% with Palmitic acid as feedstock, and the transesterification conversion reaches 56.8-73.4% with soybean oil asfeedstock. With the mixture of Soybean oil and Palmitic acid (FA content of 20.3 wt% ) as feedstock, the content offatty acid methyl esters (FAME) in products reaches 67.3-83.4% .

Analysis and improvement of output power drop of dynamic wireless power transfer systems with transmitting coil switching for inspection robots

Yishuo Ding,Jiangui Li,Longyang Wang,Chen Wang,Guofu Zhu,Yuying Cheng,Tianqi Yu 전력전자학회 2022 JOURNAL OF POWER ELECTRONICS Vol.22 No.12

Dynamic wireless power transfer (DWPT) has received extensive attention due to its advantages of high security, high convenience, and high efficiency. To solve the problems of the mutual inductance and output power drop of DWPT systems for inspection robots, a new DWPT system with a trapezoidal-rectangular coupler has been proposed. First, the DWPT system topology and the switching strategy of the transmitting coil are introduced. Second, the real-time mutual inductances of the coupler in linear and curved motion are derived. Third, a new trapezoidal transmitting coil is presented. Finally, the performance of the DWPT system with the trapezoidal-rectangular coupler (TRC) is tested and compared to the DWPT system with the rectangular-rectangular coupler (RRC). Experimental results show that the minimum mutual inductance of the TRC is increased by 58.71%, and that the minimum output power is more than doubled in curved motion. Moreover, the mutual inductance drop rates of the TRC in linear and curved motion are reduced by 21.23% and 18.42%, respectively. The output power drop rates of the TRC-DWPT system are reduced by 18.99% and 16.12%, respectively. In addition, the Litz wire consumption is reduced by 8.28% in linear motion.

Changes in the microbial community of Litopenaeus vannamei larvae and rearing water during different growth stages after disinfection treatment of hatchery water

Duan Yafei,Tang Yapeng,Huang Jianhua,Zhang Jiasong,Lin Heizhao,Jiang Shigui,Wang Ruixuan,Wang Guofu 한국미생물학회 2020 The journal of microbiology Vol.58 No.9

Microbial communities greatly affect rearing water quality and the larvae health during shrimp hatchery periods. In this study, we investigated the microbial communities of rearing water and larvae of Litopenaeus vannamei after treating hatchery water with different kinds of chemical disinfectants: no disinfectants (Con), chlorine dioxide (ClO2), formaldehyde solution (HCHO), bleach powder (CaClO), and iodine (I2). The water and larval samples were collected from nauplius 6 (N6), zoea 1 (Z1), mysis 1 (M1), and postlarvae 1 (P1) shrimp growth periods. 16S rDNA high-throughput sequencing revealed that the bacterial composition of the rearing water was more complex than that of the larvae, and the bacterial community of the rearing water and the larvae fluctuated significantly at the P1 and Z1 periods, respectively. Disinfectants altered the bacterial diversity and composition of the rearing water and larvae. Specifically, in the rearing water of the P1 period, Proteobacteria abundance was increased in the HCHO group; while Bacteroidetes abundance was decreased in the ClO2, HCHO, and I2 groups but increased in the CaClO group. In the larvae of the Z1 period, Firmicutes (especially Bacillus class) abundance was increased in the CaClO group, but decreased in the ClO2, HCHO, and I2 groups. Network analyses revealed that the genera Donghicola, Roseibacterium, Candidatus-Cquiluna, and Nautella were enriched in the rearing water, while Halomonas, Vibrio, and Flavirhabdus had high abundance in the larvae. The survival of shrimp was influenced by disinfectants that were inconsistent with the bacterial community changes. These results will be helpful for using microbial characteristics to facilitate healthy shrimp nursery.

Presulfidation and activation mechanism of Mo/Al2O3 catalyst sulfided by ammonium thiosulfate

Mingxing Tang,Xuekuan Li,Hui Ge,Weibin Fan,Guofu Wang,Zhanjun Lyu 한국화학공학회 2014 Korean Journal of Chemical Engineering Vol.31 No.8

Mo/Al2O3 catalyst was presulfided with (NH4)2S2O3 to elucidate presulfidation and activation mechanism. Itis illustrated that the Mo oxide is firstly partially sulfided during presulfidation and then in situ reduced into MoS2−x inactivation, and finally sulfided to active state during hydrodesulfurization (HDS). A synergistic effect between the S2− andS6+ ions in (NH4)2S2O3 produces a positive influence on the HDS performance. The S2− ions contribute to the sulfidationof Mo ions, while the S6+ species interact with Al2O3 support, weakening the interaction of active species with support.