Rejection rate and mechanisms of drugs in drinking water by nanofiltration technology

Sijie Ge,Li Feng,Liqiu Zhang,Qiang Xu,Yifei Yang,Ziyuan Wang,Ki-Hyun Kim 대한환경공학회 2017 Environmental Engineering Research Vol.22 No.3

Nanofiltration (NF) technology is a membrane-based separation process, which has been pervasively used as the high-effective technology for drinking water treatment. In this study, a kind of composite polyamide NF thin film is selected to investigate the removal efficiencies and mechanisms of 14 trace drugs, which are commonly and frequently detected in the drinking water. The results show that the removal efficiencies of most drugs are quite high, indicating the NF is an effective technology to improve the quality of drinking water. The removal efficiencies of carbamazepine, acetaminophen, estradiol, antipyrine and isopropyl-antipyrine in ultrapure water are 78.8 ± 0.8%, 16.4 ± 0.5%, 65.4 ± 1.8%, 71.1 ± 1.5% and 89.8 ± 0.38%, respectively. Their rejection rates increase with the increasing of their three-dimensional sizes, which indicates that the steric exclusion plays a significant role in removal of these five drugs. The adsorption of estradiol with the strongest hydrophobicity has been studied, which indicates that adsorption is not negligible in terms of removing this kind of hydrophobic neutral drugs by NF technology. The removal efficiencies of indomethacin, diclofenac, naproxen, ketoprofen, ibuprofen, clofibric acid, sulfamethoxazole, amoxicillin and bezafibrate in ultrapure water are 81 ± 0.3%, 86.3 ± 0.5%, 85.7 ± 0.4%, 93.3 ± 0.3%, 86.6 ± 2.5%, 90.6 ± 0.4%, 59.7 ± 1.7%, 80.3 ± 1.4% and 80 ± 0.5%, respectively. For these nine drugs, their rejection rates are better than the above five drugs because they are negatively charged in ultrapure water. Meanwhile, the membrane surface presents the negative charge. Therefore, both electrostatic repulsion and steric exclusion are indispensable in removing these negatively charged drugs. This study provides helpful and scientific support of a highly effective water treatment method for removing drugs pollutants from drinking water.

Controlled synthesis of nanoplate, nanoprism and nanopyramid-shaped CdSe decorated on porous TiO₂ photocatalysts for visible-light-driven hydrogen evolution

Yang, Mengke,Qian, Yongteng,Du, Jimin,Yuan, Sijie,Wang, Sijia,Zhu, Xinrui,Lin, Xialing,Li, Kaidi,Li, Sujuan,Kang, Dae Joon Elsevier 2018 Ceramics international Vol.44 No.11

<P><B>Abstract</B></P> <P>Herein, we report a successful synthesis of porous TiO<SUB>2</SUB> monoliths decorated with unique nanoplate, nanoprism, and nanopyramid-shaped CdSe particles through a mild selenylation of CdO embedded inside porous TiO<SUB>2</SUB> monoliths via a hydrothermal method in a very controlled manner. Compared with pure TiO<SUB>2</SUB>, as-synthesized CdSe/TiO<SUB>2</SUB> photocatalyst not only enhances light absorption but also leads to a highly efficient charge-carrier separation. Particularly, the nanoplate-shaped 7% CdSe/TiO<SUB>2</SUB> photocatalyst (molar percentages of CdSe to TiO<SUB>2</SUB> is 7:100) exhibits an exceptional hydrogen evolution rate up to 3650 μmol h<SUP>−1</SUP> g<SUP>−1</SUP> without resorting to any noble-metal co-catalysts under visible-light irradiation owing to synergistic effects envisaged by a rational material design. Our results may provide a useful strategy to develop a highly-efficient visible-light-driven hydrogen production system via water splitting.</P>

Design and Optimization of a New Compliant Rotary Positioning Stage with Constant Output Torque

Piyu Wang,Sijie Yang,Qingsong Xu 한국정밀공학회 2018 International Journal of Precision Engineering and Vol.19 No.12

This paper presents the design, optimization, and experimental testing of a new compliant rotary positioning stage with constant torque output. The constant-torque rotary stage is devised based on flexure-based zero-stiffness beams. It exhibits a simpler structure than existing works and is easier to fabricate. Based on the principle of zero-stiffness beam, the dominant parameters are determined by introducing an optimization algorithm. The performance of the rotary stage is verified by executing finite element analysis (FEA) simulation study, which predicts that the designed stage caters for the desired objective. A prototype rotary stage is fabricated by 3D printer for rapid prototyping. Experimental studies are carried out to validate the proposed conceptual design. Repeatability test verifies the stability and feasibility of the designed constant-torque rotary stage.

Experimental study on FeIICit enhanced absorption of NO in (NH4)2SO3 solution

Bei Yan,Jiehong Yang,Meng Guo,Sijie Zhu,Weijing Yu,Shuangchen Ma 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.21 No.1

FeIICit and (NH4)2SO3 mixed solution was selected as denitrification absorbent, and enhanced absorptionof NO was studied in a bubbling reaction column. The results show that, the highest NO removalefficiency achieved under the molar ratio of FeII to Cit was 1:2, NO removal efficiency decreased slightlywith the increase of pH in the range of experimental pH, the NO removal efficiency reduced with theincrease of temperature. NO removal efficiency increased slightly with the increasing concentrations ofimport NO, but decreased with the increasing gas flow rate. Validated experiment was carried out underthe optimum conditions in the double columns, the NO removal efficiency reached up to 71.66% within1 min and 48.14% within 6 min.

Highly efficient hydrogen evolution catalysis based on MoS₂/CdS/TiO₂ porous composites

Du, Jimin,Wang, Huiming,Yang, Mengke,Zhang, Fangfang,Wu, Haoran,Cheng, Xuechun,Yuan, Sijie,Zhang, Bing,Li, Kaidi,Wang, Yina,Lee, Hyoyoung Elsevier 2018 International journal of hydrogen energy Vol.43 No.19

<P><B>Abstract</B></P> <P>Efficient production of hydrogen through visible-light-driven water splitting mechanism using semiconductor-based composites has been identified as a promising strategy for converting light into clean H<SUB>2</SUB> fuel. However, researchers are facing lots of challenges such as light absorption and electron-hole pair recombination and so on. Here, new sheet-shaped MoS<SUB>2</SUB> and pyramid-shaped CdS <I>in-situ</I> co-grown on porous TiO<SUB>2</SUB> photocatalysts (MoS<SUB>2</SUB> CdSTiO<SUB>2</SUB>) are successfully obtained <I>via</I> mild sulfuration of MoO<SUB>3</SUB> and CdO coexisted inside porous TiO<SUB>2</SUB> monolith by a hydrothermal route. The scanning electron microscopy and transmission electron microscopy results exhibit that the MoS<SUB>2</SUB> CdSTiO<SUB>2</SUB> composites have average pore size about 500 nm. The 3%MoS<SUB>2</SUB> 10%CdSTiO<SUB>2</SUB> demonstrated excellent photocatalytic activity and high stability for a hydrogen production with a high H<SUB>2</SUB>-generation rate of 4146 μmol h<SUP>−1</SUP> g<SUP>−1</SUP> under visible light irradiation even without noble-metal co-catalysts. The super photocatalytic performance of the visible-light-driven hydrogen evolution is predominantly attributed to the synergistic effect. The conduction band of MoS<SUB>2</SUB> facilitates in transporting excited electrons from visible-light on CdS to the porous TiO<SUB>2</SUB> for catalytic hydrogen production, and holes to MoS<SUB>2</SUB> for inhibiting the photocorrosion of CdS, respectively, leading to enhancing the efficient separation of electrons and holes.</P> <P><B>Highlights</B></P> <P> <UL> <LI> MoS<SUB>2</SUB>-CT photocatalysts have been successfully synthesized by two-step method. </LI> <LI> The porous structure can enhance photogenerated electron-hole pairs separation. </LI> <LI> The 3% MoS<SUB>2</SUB>-CT shows an excellent H<SUB>2</SUB> evolution rate of 4146 μmol h<SUP>−1</SUP> g<SUP>−1</SUP>. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Reusable, magnetic laser-induced graphene for efficient removal of organic pollutants from water

Jiang Ye,Wan Sijie,Zhao Weiwei,Yu Wenjie,Wang Shuaipeng,Yu Zeqi,Yang Qiu,Zhou Weihua,Liu Xiaoqing 한국탄소학회 2022 Carbon Letters Vol.32 No.4

The hybridization of graphene with magnetic nanoparticles has endowed graphene with increasing interest as the adsorbent for wastewater treatment. However, its fabrication often involves a multi-stepped chemical synthesis process. In this work, we demonstrate a facile, one-step, and solvent-free approach to fabricate Fe3O4 nanoparticle-anchored Laser-Induced Graphene (Fe3O4@LIG) as an efficient adsorbent by direct laser irradiation on a ferric acetylacetonate containing polybenzoxazine film. Raman and X-ray diffraction analysis confirm the graphene component in the adsorbent, and the morphology characterizations show that Fe3O4 nanoparticles are distributed uniformly on LIG with hierarchical meso- and macro-porous structures. Adsorption experiments indicate that Fe3O4@LIG can adsorb methylene blue (MB) from aqueous solutions in a fast and effective manner, with a maximum adsorption capacity up to 350.9 mg/g. The adsorption kinetics and isotherms are also investigated, which are well-described by the pseudo-second-order model and Langmuir model, respectively. Additionally, Fe3O4@LIG is also demonstrated with the efficient removal of a variety of organic solvents from water. The favorable adsorption behavior of Fe3O4@LIG is attributed to its unique porous structure and the molecular interactions with adsorbates. On the other hand, Fe3O4@LIG has high magnetic property, and therefore, it could be easily recovered from water and well regenerated for repeated use. With the efficient adsorption of organic pollutants, magnetic separability, and good recyclability, it is believed that the easy-fabricated Fe3O4@LIG has great potential applications in wastewater treatment.

LTE-Advanced 상향링크에서 Device-to-Device 통신을 위한 영역 정보 기반 자원 할당 기법

리향(Xiang Li),양모찬(Mochan Yang),손세걸(Sijie Sun),신요안(Yoan Shin) 한국통신학회 2014 한국통신학회 학술대회논문집 Vol.2014 No.6

The Influence Factors and Mechanism of Psychosocial Adaptation in Patients with Endocrine Therapy for Prostate Cancer: Based on Society-to-Cells Framework

Hanjing Zhu,Jia Gu,Xia Yuan,Sijie You,Yan Yang 한국간호과학회 2023 한국간호과학회 학술대회 Vol.2023 No.11