Akebia trifoliate koiaz peels extract as environmentally benign corrosion inhibitor for mild steel in HCl solutions: Integrated experimental and theoretical investigations

Mengqin Zhang,Lei Guo,Mengyue Zhu,Kai Wang,Renhui Zhang,Zhongyi He,Yuanhua Lin,Senlin Leng,Valentine Chikaodili Anadebe,Xingwen Zheng 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.101 No.-

In this account, pectin components were obtained from akebia trifoliate koiaz peels with the acid extractiontechnology. The chemical constituent of the akebia trifoliate koiaz peels extract (ATKPE) was analyzedand its anti-corrosion performance for mild steel in HCl medium was investigated byelectrochemical methods, surface analysis and theoretical calculations. Experimental results show thatATKPE exhibits excellent corrosion inhibition characteristic, and its inhibition efficiency can be as highas 90% when the concentration of ATKPE is 800 mg/L. Electrochemical measurements show that ATKPEis a mixed-type corrosion inhibitor consisting with Langmuir adsorption model. In addition, SEM, AFMand contact angle observations suggests that the ATKPE may attach firmly to the metal surface by forminga barrier film. XPS and ATR-FTIR results further verify the bonding interaction between the functionalgroups and steel substrate. Meanwhile, quantum chemical calculations and molecular dynamics (MD)simulations were performed to reveal the inhibition mechanism at molecular/atomic level. In brief, ourfindings demonstrate a novel environmentally benign, efficient corrosion inhibitor for steel protection inacidic media.

Ultrasonic Synthesis of Au/AgCl Hybrid Cubes and Their Evolution Under Electron Beam Irradiation

Hongliang Cao,Xiaoli Miao,Mengqin Zhu,Chang Li,Feifei Wei,Xin Chen 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2015 NANO Vol.10 No.6

The utilization of ultrasound offers a facile tool for the synthesis of Au/AgCl hybrid particles. We have obtained the architectures of Au nanoparticles on AgCl sub-micrometer cubes by simply ultrasonic irradiating their precursors in ethylene glycol (EG). The formation process of Au/AgCl hybrid particles in the reaction solution has been studied based on the optical absorption spectra and the scanning electron microscope (SEM) images of the particles obtained at different ultrasonic irradiation stages. The dynamic changes of Au/AgCl hybrid particles under electron beam irradiation have been investigated in both SEM and in situ liquid cell transmission electron microscope (TEM). Hollow Au/AgCl hybrid particle structures have been obtained under the electron beam irradiation in liquid, with the cuboid contour shape preserved.

Strong convergence of monotone CQ iterative process for asymptotically strict pseudo-contractive mappings

Hong Zhang,Yongfu Su,Mengqin Li 한국전산응용수학회 2009 Journal of applied mathematics & informatics Vol.27 No.3

T.H. Kim, H.K. Xu, [Convergence of the modified Mann’s it- eration method for asymptotically strict pseudo-contractions, Nonlinear Anal.(2007),doi:10.1016/j.na.2007.02.029.] proved the strong convergence for asymptotically strict pseudo-contractions by the classical CQ iterative method. In this paper, we apply the monotone CQ iterative method to modify the classical CQ iterative method of T.H. Kim, H.K. Xu, and to obtain the strong convergence theorems for asymptotically strict pseudo- contractions. In the proved process of this paper,Cauchy sequencesmethod is used, so we complete the proof without using the demi-closedness prin- ciple, Opial’s condition or others about weak topological technologies. In addition, we use a ingenious technology to avoid defining that F(T ) is bounded. On the other hand, we relax the restriction on the control se- quence of iterative scheme. T.H. Kim, H.K. Xu, [Convergence of the modified Mann’s it- eration method for asymptotically strict pseudo-contractions, Nonlinear Anal.(2007),doi:10.1016/j.na.2007.02.029.] proved the strong convergence for asymptotically strict pseudo-contractions by the classical CQ iterative method. In this paper, we apply the monotone CQ iterative method to modify the classical CQ iterative method of T.H. Kim, H.K. Xu, and to obtain the strong convergence theorems for asymptotically strict pseudo- contractions. In the proved process of this paper,Cauchy sequencesmethod is used, so we complete the proof without using the demi-closedness prin- ciple, Opial’s condition or others about weak topological technologies. In addition, we use a ingenious technology to avoid defining that F(T ) is bounded. On the other hand, we relax the restriction on the control se- quence of iterative scheme.

STRONG CONVERGENCE OF MONOTONE CQ ITERATIVE PROCESS FOR ASYMPTOTICALLY STRICT PSEUDO-CONTRACTIVE MAPPINGS

Zhang, Hong,Su, Yongfu,Li, Mengqin The Korean Society for Computational and Applied M 2009 Journal of applied mathematics & informatics Vol.27 No.3

T.H. Kim, H.K. Xu, [Convergence of the modified Mann's iteration method for asymptotically strict pseudo-contractions, Nonlinear Anal.(2007),doi:l0.l016/j.na.2007.02.029.] proved the strong convergence for asymptotically strict pseudo-contractions by the classical CQ iterative method. In this paper, we apply the monotone CQ iterative method to modify the classical CQ iterative method of T.H. Kim, H.K. Xu, and to obtain the strong convergence theorems for asymptotically strict pseudo-contractions. In the proved process of this paper, Cauchy sequences method is used, so we complete the proof without using the demi-closedness principle, Opial's condition or others about weak topological technologies. In addition, we use a ingenious technology to avoid defining that F(T) is bounded. On the other hand, we relax the restriction on the control sequence of iterative scheme.

A Novel Electrochemical Method for Sensitive Detection of Melamine in Infant Formula and Milk using Ascorbic Acid as Recognition Element

Li, Junhua,Kuang, Daizhi,Feng, Yonglan,Zhang, Fuxing,Xu, Zhifeng,Liu, Mengqin Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.8

A novel and convenient electrochemical method has been developed for sensitive determination of melamine (MEL) using ascorbic acid (AA) as the recognition element. The working electrode employed in this method was modified with the nanocomposite of hydroxyapatite/carbon nanotubes to enhance the current signal of recognition element. The interaction between MEL and AA was investigated by fourier transform infrared spectroscopy and cyclic voltammetry, and the experimental results indicated that hydrogen bonding was formed between MEL and AA. Because of the existing hydrogen bonding and electrostatic interaction, the anodic peak current of AA was decreased obviously while the non-electroactive MEL added in. It illustrated that the MEL acted as an inhibitor to the oxidation of AA and the decreasing signals can be used to detect MEL. Under the optimal conditions, the decrease in anodic peak current of AA was proportional to the MEL concentrations ranging from 10 to 350 nM, with a detection limit of 1.5 nM. Finally this newly-proposed method was successfully employed to detect MEL in infant formula and milk, and good recovery was achieved.

Alpha radionuclide-chelated radioimmunotherapy promoters enable local radiotherapy/chemodynamic therapy to discourage cancer progression

Jiajia Zhang,Feize Li,Yuzhen Yin,Ning Liu,Mengqin Zhu,Han Zhang,Weihao Liu,Mengdie Yang,Shanshan Qin,Xin Fan,Yuanyou Yang,Kun Zhang,Fei Yu 한국생체재료학회 2022 생체재료학회지 Vol.26 No.4

Background: Astatine-211 is an α-emitter with high-energy α-ray and high cytotoxicity for cancer cells. However, the targeted alpha therapy (TAT) also suffers from insufficient systematic immune activation, resulting in tumor metastasis and relapse. Combined immune checkpoint blockade (ICB) with chemodynamic therapy (CDT) could boost antitumor immunity, which may magnify the immune responses of TAT. This study aims to discourage tumor metastasis and relapse by tri-model TAT-CDT-ICB strategy. Methods: We successfully designed Mn-based radioimmunotherapy promoters (211At-ATE-MnO2-BSA), which are consisting of 211At, MnO2 and bovine serum albumin (BSA). The efficacy of 211At-ATE-MnO2-BSA was studied as monotherapy or in combination with anti-PD-L1 in both metastatic and relapse models. The immune effects of radioimmunotherapy promoters on cytotoxic T lymphocytes and dendritic cells (DCs) were analyzed by flow cytometry. Enzymelinked immunosorbent assay and immunofluorescence were used to explore the underlying mechanism. Results: Such radioimmunotherapy promoters could not only enhance the therapeutic outcomes of TAT and CDT, but also induce robust anti-cancer immune activity by activating dendritic cells. More intriguingly, 211At-ATE-MnO2-BSA could effectively suppress the growths of primary tumors and distant tumors when combined with immune checkpoint inhibitors. Conclusions: The tri-model TAT-CDT-ICB strategy provides a long-term immunological memory, which can protect against tumor rechallenge after eliminating original tumors. Therefore, this work presents a novel approach for TATCDT-ICB tri-modal cancer therapy with repressed metastasis and relapse in clinics.

A Novel Electrochemical Method for Sensitive Detection of Melamine in Infant Formula and Milk using Ascorbic Acid as Recognition Element

Junhua Li,Daizhi Kuang,Yonglan Feng,Fuxing Zhang,Zhifeng Xu,Mengqin Liu 대한화학회 2012 Bulletin of the Korean Chemical Society Vol.33 No.8

A novel and convenient electrochemical method has been developed for sensitive determination of melamine (MEL) using ascorbic acid (AA) as the recognition element. The working electrode employed in this method was modified with the nanocomposite of hydroxyapatite/carbon nanotubes to enhance the current signal of recognition element. The interaction between MEL and AA was investigated by fourier transform infrared spectroscopy and cyclic voltammetry, and the experimental results indicated that hydrogen bonding was formed between MEL and AA. Because of the existing hydrogen bonding and electrostatic interaction, the anodic peak current of AA was decreased obviously while the non-electroactive MEL added in. It illustrated that the MEL acted as an inhibitor to the oxidation of AA and the decreasing signals can be used to detect MEL. Under the optimal conditions, the decrease in anodic peak current of AA was proportional to the MEL concentrations ranging from 10 to 350 nM, with a detection limit of 1.5 nM. Finally this newly-proposed method was successfully employed to detect MEL in infant formula and milk, and good recovery was achieved.

Effective removal of phenol from wastewater by magnetic porous loofah biochar

Shan Shirui,Wu Honglin,Yang Jian,Jiao Di,Huang Mengqin,Li Fu 한국탄소학회 2024 Carbon Letters Vol.34 No.1

In this study, a low-cost and easily recyclable porous green adsorbent (magnetic porous loofah biochar, MPLB) was synthesized by modifying the almost zero-cost loofah biochar material with Fe3O4. The successful synthesis of the material was demonstrated by XRD, FTIR, SEM, VSM, and BET. In addition, the material exhibits outstanding magnetic separation performance (40.01 umg/g) allowing for rapid recovery within just 90 s. The adsorption process of phenol on MPLB was found to be spontaneous and endothermic. The experimental data fit exceptionally well with the pseudo-second-order kinetic model and Langmuir model (R2 > 0.99), indicating that the dominant adsorption mechanisms involved monolayer adsorption and chemisorption. These interactions were attributed to host–guest interaction, π–π conjugation, hydrogen bonding, and pore filling. The maximum adsorption capacity calculated using the Langmuir model at 298 K is 39.4 mg/g. Importantly, even after undergoing seven cycles of recycling, MPLB retained 78% of its initial adsorption capacity. In simulated experiments employing MPLB for phenol removal in actual wastewater, an impressive removal rate of 96.4% was achieved. In conclusion, MPLB exhibits significant potential as an effective adsorbent for phenol removal in wastewater. Graphical In this study, a low-cost and easily recyclable porous green adsorbent (magnetic porous loofah biochar, MPLB) was synthesized by modifying the almost zero-cost loofah biochar material with Fe3O4. The successful synthesis of the material was demonstrated by XRD, FTIR, SEM, VSM, and BET. In addition, the material exhibits outstanding magnetic separation performance (40.01 umg/g) allowing for rapid recovery within just 90 s. The adsorption process of phenol on MPLB was found to be spontaneous and endothermic. The experimental data fit exceptionally well with the pseudo-second-order kinetic model and Langmuir model (R2 > 0.99), indicating that the dominant adsorption mechanisms involved monolayer adsorption and chemisorption. These interactions were attributed to host–guest interaction, π–π conjugation, hydrogen bonding, and pore filling. The maximum adsorption capacity calculated using the Langmuir model at 298 K is 39.4 mg/g. Importantly, even after undergoing seven cycles of recycling, MPLB retained 78% of its initial adsorption capacity. In simulated experiments employing MPLB for phenol removal in actual wastewater, an impressive removal rate of 96.4% was achieved. In conclusion, MPLB exhibits significant potential as an effective adsorbent for phenol removal in wastewater. Graphical