Facile preparation of antifouling g-C3N4/Ag3PO4 nanocomposite photocatalytic polyvinylidene fluoride membranes for effective removal of rhodamine B

Yanhua Cui,Lili Yang,Minjia Meng,Qi Zhang,Binrong Li,Yilin Wu,Yunlei Zhang,Jihui Lang,Chunxiang Li 한국화학공학회 2019 Korean Journal of Chemical Engineering Vol.36 No.2

A simplified strategy for facilely fabricating antifouling graphite carbon nitride/silver phosphate (g-C3N4/ Ag3PO4) nanocomposite photocatalytic polyvinylidene fluoride (PVDF) porous membranes was developed for effective removal of rhodamine B (RhB). g-C3N4/Ag3PO4 heterojunction was strongly fixed to the interior of the PVDF membranes via phase inversion method. The membrane structure was analyzed by Fourier transform spectrophotometer (FT-IR). The morphology of the prepared membranes was investigated using scanning electron microscopy (SEM), EDX-mapping and atomic force microscopy (AFM), respectively. All prepared nanocomposite photocatalytic PVDF membranes exhibited a typically porous structure, and g-C3N4/Ag3PO4 nanocomposites were well dispersed inside the membranes. The obtained g-C3N4/Ag3PO4 heterojunction nanoparticle decorated PVDF membrane had a lower water contact angle of 79o and higher porosity of 85% than that of other two control membranes. The nanocomposite photocatalytic PVDF porous membranes had extremely high permeation flux over 1,083 L·m−2·h−1, and could be used for the removal of RhB. The removal efficiency of g-C3N4/Ag3PO4-PVDF membranes towards RhB solution under visible light irradiation reached 97%, higher than that of the pure PVDF membranes (41%) and g-C3N4-PVDF membranes (85%). Remarkably, the flux performance and flux recovery ratio (FRR) of membranes revealed that the g-C3N4/Ag3PO4- PVDF membranes could recover high flux after fouling, which presented better fouling resistance. Furthermore, the fabricated antifouling g-C3N4/Ag3PO4 nanocomposite photocatalytic PVDF porous membranes exhibited excellent recyclability. Therefore, it is expected that g-C3N4/Ag3PO4-PVDF membranes could provide an energy-saving strategy for effective removal of organic dyes wastewater and have a great potential for practical wastewater treatment in the future.

Facile synthesis of imprinted submicroparticles blend polyvinylidene fluoride membranes at ambient temperature for selective adsorption of methyl p-hydroxybenzoate

Yanhua Cui,Minjia Meng,Dongshu Sun,Yan Liu,Jianming Pan,Xiaohui Dai,Yongsheng Yan 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.3

We developed a simple phase inversion technique to prepare molecularly imprinted membrane (MIM) at room temperature for membrane selective adsorption and separation of methyl p-hydroxybenzoate (M4HB). The prepared SMIP-MIM was characterized by SEM, FT-IR, TGA. Compared with non-imprinted membrane (NIM1-5) adsorbent, SMIP-MIM1-5 adsorbent with high specific surface area and showed higher binding capacity, faster kinetic and better selectively adsorption capacity for M4HB. The maximum isotherm adsorption capacity for M4HB of SMIPMIM4 was 3.519mg·g−1, and the experimental data was well fitted to the slips model by multiple analysis. The maximum kinetic adsorption capacity and equilibrium adsorption time for SMIP-MIM4 were 1.335mg·g−1 and 160 min, respectively. The mechanism for dynamic adsorption of M4HB onto SMIP-MIM4 was found to follow pseudo-firstorder model and pseudo-second-order model. Additionally, the permeability separation factor of SMIP-MIM4 for M4HB compared to a structural analogues methyl 2-hydroxybenzoate (M2HB) could reach 2.847. The adsorption capacity of SMIP-MIM4 for M4HB and M2HB was 0.549mg·cm−2 and 1.563mg·cm−2, respectively. The adsorption behavior of M4HB through SMIP-MIM4 followed the retarded permeation mechanism.

Nature-mimicking fabrication of antifouling photocatalytic membrane based on Ti/BiOI and polydopamine for synergistically enhanced photocatalytic degradation of tetracycline

Yanhua Cui,Lili Yang,Yan Yan,Zengkai Wang,Jian Zheng,Binrong Li,Yonghai Feng,Chunxiang Li,Minjia Meng 한국화학공학회 2021 Korean Journal of Chemical Engineering Vol.38 No.2

The photocatalytic efficiency of conventional blending photocatalytic membranes suffers a significant reduction due to effective photocatalyst embedded in membrane matrix. Therefore, in this study, inspired by the bioadhesive technology of polydopamine (pDA), a novel Ti doped bismuth oxyiodide (BiOI)-polydopamine (pDA)-coated cellulose acetate (CA) (Ti/BiOI-pDA/CA) photocatalytic nanocomposite membranes were successfully developed for effective removal of tetracycline (TC). The Ti/BiOI-pDA/CA nanocomposite membranes displayed very high photocatalytic activity toward TC (about 98% after 120 min) under visible light irradiation and superior photodegradation kinetics (k=0.03214 min1). The removal rate of Ti/BiOI/-pDA/CA nanocomposite membranes under dynamic cyclic degradation system could be further improved, giving TC removal efficiency of 91% in 60min. Remarkably, the permeate flux, flux recovery ratio (FRR), reversible fouling (Rr), irreversible fouling (Rir) and the total fouling ratio (Rt) revealed the Ti/BiOI-pDA/CA nanocomposite membranes had excellent antifouling performance. In addition, the Ti/ BiOI-pDA/CA nanocomposite membranes exhibited excellent stability and reusability. Therefore, this work gives insight into the effective removal of TC wastewater and has a great potential for new generation of high-performance photocatalytic membranes for practical wastewater treatment in the future.

Molecularly imprinted electrospun nanofibre membrane assisted stir bar sorptive extraction for trace analysis of sulfonamides from animal feeds

Yahan Cui,Liyan Jiang,Huiyu Li,Di Meng,Yanhua Chen,Lan Ding,Yang Xu 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.96 No.-

The widespread addition of sulfa antibiotics in feeds has long been an environment safety issue. Therefore, it is quite meaningful to constantly propose better solutions for determining the sulfaantibiotics in the environment. Herein, molecularly imprinted electrospun nanofibre membrane (MIM)assisted stir bar sorptive extraction method for the determination sulfonamides (SAs) in feed wasdeveloped. In this study, molecularly imprinted polymers (MIPs) werefirstly prepared via emulsionpolymerization using sulfamonomethoxine as template. Then, the morphology-controllable MIM wasobtained with MIPs-doping electro-spinning solution using electro-spinning technique. Next, MIM arecoated on the magnetic stir bar by heat-sealing. Finally, MIM coated stir bar was used for selectiveenrichment of SAs. The obtained MIM exhibited excellent class selectivity towards SAs (the selectivityfactor β is 2.3–2.7). The MIM coated stir bar can be directly applied to extract SAs from feed samples. Under the optimum extraction conditions, the detection limit of the method could reach 1.5 3.4 ng/g. And satisfactory recoveries ranging from 80 6% to 89 7% were achieved under all three spiked levelsfor determination of four SAs infive different feed samples. The present work not only offers insights todevelop magnetic stir bar using imprinted membrane, but also provides a new method for SAs extraction.

Heterologous Expression and Purification of Zea mays Transglutaminase in Pichia pastoris

Hongbo Li,Yanhua Cui,Lanwei Zhang,Huaxi Yi,Xue Han,Yuehua Jiao,Ming Du,Rongbo Fan,Shuang Zhang 한국식품과학회 2014 Food Science and Biotechnology Vol.23 No.5

Transglutaminases (TGases) are a family ofenzymes that catalyze the cross-linking of proteins and arewidely used in the food industry to improve the texture ofdairy, meat, and bread products. Zea mays transglutaminase(TGZ) is a new type of TGase with a wide potential. TGZwas expressed in the yeast Pichia pastoris under an alcoholoxidase promoter. Maximal expression of recombinantTGZ was achieved by inducing recombinant GS115(pPIC9K-tgz) in BMMY medium using 1.5% methanol for96 h. Secreted TGZ was initially separated using Superdex200 resin and further purified on cation exchange resin. The activity of TGZ following purification was 0.32 U/mgof protein. The polymerization effect of TGZ on caseincatalyzed by recombinant TGZ was slightly lower than theeffect of microbial transglutaminase (MTG). TGZ is a newpotential additive for the food industry.

Optimization of recombinant Zea mays transglutaminase production and its influence on the functional properties of yogurt

Hongbo Li,Yanhua Cui,Lanwei Zhang,Lili Zhang,Hui Liu,Jinghua Yu 한국식품과학회 2017 Food Science and Biotechnology Vol.26 No.3

The requirements for the production of optimized Zea mays transglutaminase (TGZo) using Pichia pastoris GS115 (pPIC9K-tgzo) were optimized in this study. Plackett–Burman design was used to screen variables that significantly influence TGZo production. Oleic acid, methanol, and loading volume were identified as the most significant parameters. Central composite design was employed to determine the optimal level of these three parameters for TGZo production. Results showed that 1078 mU/mL of TGZo activity and 7.6 mg/L of TGZo production were obtained under conditions of 0.07% oleic acid, 1.31% methanol, and 7.36% loading volume. To explore the functional characteristics of TGZo, it was used in yogurt. It was found that the addition of TGZo could produce yogurt with stronger acid gel and higher consistency, cohesiveness, index of viscosity, and apparent viscosity than the untreated product. Therefore, TGZo can be used as a substitute for microbial transglutaminase in the yogurt, even in the food industry.

Effect of molecular weight of regenerated silk fibroin on silk-based spheres for drug delivery

Zengkai Wang,Xiangming Li,Yanhua Cui,Kai Cheng,Mingdong Dong,Lei Liu 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.10

Silk fibroin presents a good advantage as a drug carrier for drug delivery, due to the excellent biocompatibility, biodegradability and tunable drug loading and release properties. In this work, we constructed silk spheres by phase separation of the regenerated silk fibroin (RSF) solutions with different MW and polyvinyl alcohol; and it was revealed that MW of RSF can affect the structure, size, surface potential and drug loading and release efficiency of silk spheres. Silk spheres prepared from high MW of RSF were found to load more macromolecular drug with negative charge compared to middle and low MW of RSF. However, for the positive charge and low MW drug, the silk spheres prepared from low MW of RSF could present a high loading efficiency compared to other carriers. Finally, a positive drug with low MW, streptomycin was encapsulated in silk spheres prepared from low MW of RSF, and displayed a long bactericidal and bacteriostatic effect compared to bared streptomycin solution. The results obtained provide guidelines for the modification and options of drug transport vehicles for more efficient drug delivery and utilization through a simple, rapidly constructed, applicable and low-cost drug carrier.

Sensitive detection of levofloxacin and copper (II) based on fluorescence ‘‘turn on-off” of biomass carbonized polymer dots

Jiasheng Lin,Shuliang Yang,Yanjie Wang,Yahan Cui,Qiaoyan Li,Yanhua Chen,Lan Ding 한국공업화학회 2022 Journal of Industrial and Engineering Chemistry Vol.114 No.-

A novel type of biomass carbonized polymer dots (CS-CPDs) with green fluorescence emission were synthesizedvia a one-step microwave-assisted method, using chitosan and maleic acid as the precursors. The fluorescence intensity of CS-CPDs was selectively enhanced (turn on) with increasing levofloxacin(LEV) concentration based on Aggregation Induced Emission Enhancement. The linear range of thismethod was 1–35 lmol/L, with the limit of detection of 0.20 lmol/L. Furthermore, we demonstrated thatthe fluorescence intensity of CS-CPDs/LEV was restored (turn on-off) due to the addition of copper (II),which could assemble a more stable Cu2+/LEV complex through coordination. For the first time, CSCPDswere utilized as a selective fluorescent ‘‘turn on-off” probe for the continuous detection of LEVand Cu2+. Excellent results were also obtained in environmental water samples analysis with recoveriesranging of 91.3–99.6% and 97.7–113.4%, respectively. Moreover, the prepared CS-CPDs exhibited excellentoptical stability and large Stokes shift (139 nm), which predicted broad application prospects inthe field of fluorescence sensing.

An Access Control Mechanism based on Permission Delegation in P2P Network

ZHANG Changyou,LIU Renfen,CAO Yuanda,LI Yanhua,CUI Liang 보안공학연구지원센터 2008 International Journal of Security and Its Applicat Vol.2 No.2

P2P(Peer-to-Peer) is a popular model in distributed computing. We present an access control mechanism based on permission delegation in this paper. This mechanism consists of three protocols, i.e. agency discovering protocol, permission delegating protocol and resource access protocol. Firstly, the task initiator decomposes the task into subtasks and chooses other peers in high trust degree with satisfied abilities to accomplish these subtasks. We call these neighbors as task agents. Then task initiator temporarily transfers some necessary permission to subtask agents by means of credit certificate and delegation certificate. Finally, the subtask agents consume resources of resource peers followed access protocol. These protocols are analyzed in Colored Petri-Net, and simulated with CPN Tools.

Efficacy and Safety of Pulse Magnetic Therapy System in Insomnia Disorder: A Multicenter, Randomized, Double-Blind, Placebo-Controlled Trial

Liao Jiwu,Wang Sisi,Zhou Borong,Liang Wei,Ma Ping,Lin Min,Lin Weisen,Li Congrui,Zhang Xiaotao,Li Hongyao,Cui Yin,Hu Jiajia,Qin Yuanyi,Deng Yanhua,Fu Aibing,Zhu Tianhua,Zhang Shanlian,Qu Yunhong,Xing L 대한신경정신의학회 2023 PSYCHIATRY INVESTIGATION Vol.20 No.6

Objective This study’s objective is to assess the efficacy and safety of Pulsed Magnetic Therapy System (PMTS) in improving insomnia disorder.Methods Participants with insomnia disorder were randomly assigned to receive either PMTS or sham treatment for four weeks (n= 153; PMTS: 76, sham: 77). Primary outcomes are the Insomnia Severity Index (ISI) scores at week 0 (baseline), 1, 2, 3, 4 (treatment), and 5 (follow-up). Secondary outcomes are the Pittsburgh Sleep Quality Index at baseline and week 4, and weekly sleep diary-derived values for sleep latency, sleep efficiency, real sleep time, waking after sleep onset, and sleep duration.Results The ISI scores of the PMTS group and the sham group were 7.13±0.50, 11.07±0.51 at week 4, respectively. There was a significant group×time interaction for ISI (F3.214, 485.271=24.25, p<0.001, ηp 2=0.138). Only the PMTS group experienced continuous improvement throughout the study; in contrast, the sham group only experienced a modest improvement after the first week of therapy. At the end of the treatment and one week after it, the response of the PMTS group were 69.7% (95% confidence interval [CI]: 58.6%–79.0%), 75.0% (95% CI: 64.1%–83.4%), respectively, which were higher than the response of the sham group (p<0.001). For each of the secondary outcomes, similar group×time interactions were discovered. The effects of the treatment persisted for at least a week.Conclusion PMTS is safe and effective in improving insomnia disorders.