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Pyrolysis-coupled gasification-melting is a promising technology as it can dispose of the petrochemical sludge (PS) and recover the leftover energy. Unfortunately, there has been little research investigating the effects of pyrolysis degree on melting characteristics of the pyrolysis residue (PR) and the transformation properties of the heavy metal (HM). In this study, the function of inherent components and disposal temperature were elucidated. The results show that the moisture and light volatile could disperse the melting residue (MR) during gasification-melting treatment, causing different morphology and color of the MR. In addition, as pyrolysis temperature increased, the HMs speciation (e.g. Zn, Cu, and Cr) in the PR was transformed from bioavailable to a stable state, and the yield of PR decreased from 66.8% to 36.5%. The PR produced at 800 °C could decrease about 0.9 ∼ 1.9 potential ecological risk of releasing substances during the subsequent high-temperature gasification-melting owing to its stable HMs state and less char composition. Moreover, the gasification at 1250 °C could realize the safe disposal of the PR. Further increasing the gasification temperature to 1450 °C could not improve the acid-leaching resistance of the HMs, although the apparent concentration of C and the acid dissolution proportion of slag decreased by 6.3% and 1.7%, respectively., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

To understand the potential effects of intrinsic calcium compounds on sludge pyrolysis, the pyrolysis behavior of petrochemical sludge (PS), calcium carbonate blend PS (CaPS), and decalcified PS (DePS) were investigated using thermogravimetric analysis (TGA) and in-situ Fourier-transform infrared spectroscopy coupled with pyrolysis-gas chromatography and mass spectrometry (Py-GC/MS). The TGA results indicated that decalcification increased and decreased the energy barriers of PS decomposition in ranges 200-350 °C and 350-600 °C, respectively. In contrast, copyrolysis with CaCO 3 decreased the activation energy (E) of the pseudoreaction phase 2 (PH2) and altered the mechanism model. Meanwhile, during copyrolysis, char deposition and interaction hindered CaCO 3 decomposition. The two-dimensional correlation spectroscopy results, on the other hand, showed that the reaction priority of O-containing groups and CH- vibration of methyl groups were affected by both decalcification and CaCO 3 copyrolysis. The Py-GC/MS results indicated that the three sludges mainly released hydrocarbons, N-containing organics, alcohols, aldehydes, and acids. During pyrolysis, CaCO 3 also played a neutralization role, which reduced the release of pyrolytic acidic products. In addition, the increase of the pyrolysis temperature increased the hydrocarbon content. This research will guide the industrial application of sludge pyrolysis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In this study, a novel magnetic molecularly imprinted polymer (MMIP) was prepared by surface imprinting technology using 2-oxin and 6-HNA as dual virtual templates and 4-vinyl pyridine (4-VP) as the functional monomer for extraction of patulin (PAT) from the surface of magnetic nanoparticles. MMIPs were characterized by fourier transformed infrared (FT-IR) spectroscopy, X-ray diffraction, and vibrating sample magnetometry. The results showed that the molecularly imprinted polymer (MIP) was successfully coupled with magnetic nanoparticles and could be used as a magnetic selective recognition material. Moreover, MMIPs have a greater adsorption capacity for PAT than conventional MIPs. The magnetic dispersion solid-phase extraction procedure was optimized and then combined with liquid chromatography-tandem mass spectrometry (MDSPE-LC-MS/MS) for detection of PAT in juice samples. The method showed excellent analytical performance in terms of linearity (ranged between 0.5 μg L -1 and 100 μg L -1 with correlation coefficients (r) higher than 0.999) and limit of detection (LOD) (0.1 μg L -1 , S/N = 3). At three spiking concentrations (1, 10, and 50 μg L -1 ), the mean recoveries were ranged between 79.4% and 97.9% with relative standard deviations (RSDs) < 4.7% (n = 3)., Competing Interests: Declaration of Competing Interest Authors have declared no conflicts of interest., (Copyright © 2019. Published by Elsevier B.V.)

Functional magnetic nanomaterials based on molecular imprinting technique were successfully prepared on the surface of modified Fe 3 O 4 . Transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffractometer, and vibrating sample magnetometry were applied for characterization of the synthesized magnetic nanoparticles. The magnetic molecularly imprinted polymers (MMIPs) exhibited satisfactory magnetic response, specific recognition, and excellent adsorption capacity toward triazoles (maximum adsorption capacity of 9202.9 μg g -1 for triadimefon). The obtained MMIPs were further used as magnetic dispersive solid-phase extraction (MDSPE) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) for detection of 20 triazoles in cucumber spiked at different levels. The mean recoveries were ranged from 79.9% to 110.3% and relative standard deviations (RSDs) were <11.2% (n = 5). Herein, we report a simple, rapid, environmentally friendly, and magnetic stuff recyclable approach for triazoles residual analysis in complicated agricultural products., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A molecularly imprinted polymer (MIP) with specific adsorption for patulin was successfully polymerized by precipitation polymerization using 2-oxindole (2-oxin) and 6-hydroxynicotinic acid (6-HNA) as dummy template molecules, methylacrylic acid (MAA) as a functional monomer, trimethylolpropane trimethacrylate (TRIM) as a crosslinker, 2,2-azobis-(2-methylpropionitrile) (AIBN) as a initiator, and methanol as a porogen solvent. The molecularly imprinted solid phase extraction (MI-SPE) column was prepared using the polymer as a sorbent and applied for the selective extraction of patulin from real samples. The results showed that the MI-SPE method had high selectivity and specific adsorption towards patulin with mean recoveries ranged between 81.3% and 106.3% and a relative standard deviation (RSD) < 4.5%. Additionally, the developed MI-SPE method coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) exhibited good linearity in the range of 1-100 ng mL - 1 with correlation coefficients (R 2 ) >0.998. The limits of detection (LODs, S/N = 3) were 0.05-0.2 ng g - 1 , and the limits of quantification (LOQs, S/N = 10) were 0.2-0.5 ng g - 1 . The developed method showed a better purification and higher patulin recovery for real samples than the quick, easy, cheap, effective, rugged, safe "QuEChERS" method., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Herein, a novel magnetic molecularly imprinted polymer doped with reticular graphene oxide (Fe 3 O 4 @SiO 2 -GO@MIPs) was synthesized for the selective recognition and extraction of 4 flavonoids (farrerol, taxifolin, kaempferol, and hyperin) from Rhododendrons species. The Fe 3 O 4 @SiO 2 -GO@MIPs with lamellar membranes showed outstanding adsorption capacity. The 3D cavities complementary to the "shape" of farrerol were "imprinted" on the polymer framework after removal of farrerol template. Competitive binding assays showed that the polymer has a higher selectivity for farrerol compared with other analogues and references. The Fe 3 O 4 @SiO 2 -GO@MIPs as solid-phase extraction adsorbents combined with liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS) was used for selective determination of four flavonoids from Rhododendrons samples. The limits of detection (LOD) were 0.07, 0.08, 0.06, and 0.08 μg L -1 for farrerol, taxifolin, kaempferol, and hyperin, respectively. These results suggest that the prepared Fe 3 O 4 @SiO 2 -GO@MIPs have the potential applicability to extract, purify, and enrich flavonoids from herbs, supplements, and other natural products., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Salidroside is one of the bio-active compounds found in Rhodiola crenulata. To find an easy, time saving and efficient way to extract, purify and enrich salidroside from Rhodiola and other natural plants, we prepared a highly selective molecularly imprinted polymer (MIP) for extraction and preconcentration of salidroside using salidroside (SD) as a template, acrylamide (AM) as a functional monomer, ethylene glycol dimethacrylate (EDMA) as a crosslinking monomer, and dimethyl formamide (DMF) as a porogen. The performance of the MIPs was evaluated through selective recognition capacity and adsorption isotherms and kinetics. The results showed that MIPs possessed excellent specific recognition toward SD and could effectively discriminate its structural analogue. The application of the developed MIPs as a selective sorbent for solid-phase extraction (SPE) of SD was also investigated. Under the optimum conditions, a rapid, economical, and efficient method based upon MIP-SPE coupled with high-performance liquid chromatography (HPLC) was developed for the determination of SD in Rhodiola crenulata. The method showed satisfactory recoveries (from spiked real samples at 3 fortification levels of 0.5, 1 and 10 mg L -1 ) of 88.74%- 97.64% with relative standard deviations (RSDs) ranging from 2.05%-3.54%. Furthermore, MIP-SPE was successfully used to separate and purify SD from different parts in Rhodiola crenulata and it should be available for determination of salidroside in others herbs., (Copyright © 2019 Elsevier B.V. All rights reserved.)

We aim to develop a solid-phase extraction (SPE) based on a dummy molecularly imprinted polymer (MIP) and liquid chromatography-tandem quadrupole mass spectrometry (LC-MS/MS) for selective determination of four pyridine carboxylic acid herbicides (aminopyralid, picloram, fluroxypyr, and clopyralid) in milk samples. Using picloram as the dummy template, MIP nanocomposites with highly selective recognition and adsorption for the target molecule and its structural analogs were successfully synthesized by precipitation polymerization. Adsorption isotherms and kinetics were used to determine the adsorption performance and specific recognition mechanism of both MIPs and non-molecularly imprinted polymers (NIP). The Scatchard plot analysis revealed that two different binding sites were formed in the MIP with maximum binding capacity (Q max ) of 1171.8 μg·g -1 and 3022.5 μg·g -1 , respectively. Recovery at three spiking levels of 10, 20, and 50 μg·L -1 ranged between 75.3 and 89.8% with relative standard deviations (RSDs) <14.3%.The limit of detection (LOD) was estimated to be 0.124 μg·L -1 . Finally, the feasibility of the proposed methodology was successfully applied to quantify aminopyralid and another three pyridine carboxylic acid herbicides in milk., (Copyright © 2019. Published by Elsevier B.V.)

In the present work, we report on an experimental study of flexible nanocomposite film for electrochemical detection of hydrogen peroxide (H2O2) based on bacterial cellulose (BC) and multi-walled carbon nanotubes (MWCNTs) in combination with microperoxidase-11 (MP-11). MWCNTs are used to functionalize BC and provide a flexible conductive film. On the other hand, BC can improve MWCNTs׳ biocompatibility. The investigation shows that MP-11 immobilized on the flexible film of MWCNTs-BC can easily present a pair of well-defined and quasi-reversible redox peaks, revealing a direct electrochemistry of MP-11 on the nanocomposite film. The apparent heterogeneous electron-transfer rate constant ks is estimated to be 11.5s(-1). The resulting flexible electrode presents appreciated catalytic properties for electrochemical detection of H2O2, comparing to traditional electrodes (such as gold, glassy carbon electrode) modified with MP-11. The proposed biosensor exhibits a low detection limit of 0.1 µM (at a signal-to-noise ratio of 3) with a linear range of 0.1-257.6 µM, and acquires a satisfactory stability., (Copyright © 2014 Elsevier B.V. All rights reserved.)