CHEMICAL ENGINEERING JOURNAL
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2020
·
IF 10.652
Jialin Jia,Dongmei Liu,Jiayu Tian,Wei Wang,Jiaxin Ni,Xin Wang
In this study, a novel peroxymonosulfate (PMS) activation method by visible light (VL) excited humic acid (HA) was developed and applied to degradation of bisphenol A (BPA). Results showed that, in HA (2 mg/L)/PMS (1 mM)/VL system, the degradation rate of BPA could reach 95.4% within 30 min, which was much higher than that of HA/VL system (9.4%) and PMS/VL system (15.5%). Meanwhile, the concentration of HA was also decreased in this process and the original structure of HA was obviously destroyed. Reaction mechanism accounting for the effect of HA on BPA degradation in the PMS/HA/VL system was explicated by the quenching experiments, electron paramagnetic resonance (EPR) detection and HA fractionation experiments. Results showed that singlet oxygen ( 1 O 2 ), hydroxyl radical ( OH) and sulfate radical (SO 4 − ) were all involved in the system, and 1 O 2 was the primary reactive species responsible for BPA degradation. The aromatic constituents of HA made the dominant contribution to the generation of reactive species, in which the phenolic groups played the role of electron-donor, and the quinone moieties acted as the electron shuttles could accelerate the electron-transfer between HA and PMS, which thus activated PMS to form the reactive species for BPA degradation. As HA is ubiquitous in nature, this study may provide a new insight into the in situ water treatment with the assistance of PMS.
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高影响因子
CHEMICAL GEOLOGY
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2020
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IF 3.363
Jing-Jing Fan,Jie Li,Qiang Wang,Le Zhang,Jing Zhang,Xiang-Lan Zeng,Lin Ma,Zi-Long Wang
Recent advances in analytical techniques have achieved high-precision (2σ ≤ 0.06‰) determinations of Mo isotopic ratios in silicate rocks but few such data are as yet available, especially for low-Mo (<50 ppb) rocks such as leucogranites . Here we present two low-blank, double-spike, high-yield, ion-exchange chromatographic methods (single- and two-column) for precise determination of Mo isotopic ratios in low-Mo rock samples (10–500 ppb) using multicollector–inductively coupled plasma–mass spectrometry (MC–ICP–MS). The two-column technique involved AG 1-X8 anion-exchange (100–200 mesh) and BPHA chelatin resins, with the latter also used in the single-column procedure. Two USGS reference materials (basalt BIR-1a and diabase W-2a) were analyzed for quality-control purposes. Their δ 98/95 Mo values determined using the two methods are consistent within uncertainties, and with those determined by previously published methods. We provide the first Mo isotopic data for the reference materials of dunite DTS-2b (USGS), GPt-3 (NRCG) and peridotite WPR-1 (CCRMP). δ 98/95 Mo values for DTS-2b and WPR-1 by using two-column procedure are in good agreement with those obtained by single-column separation. Repeated analyses of these standards indicate a long-term external reproducibility of better than ±0.05‰. However, the δ 98/95 Mo values of GPt-3 show poor reproducibility due to either the sample heterogeneity or existing undigested minerals (e.g., spinel). The methods were applied to leucogranites with low Mo contents of 10–74 ppb from the Himalaya orogen and southern Lhasa terrane of Tibet . The isotopic analyses yielded δ 98/95 Mo values of −0.2‰ to 0.34‰ and −0.41‰ to −0.68‰ (against NIST SRM 3134), respectively, within the range of values for igneous crust. Their contrasting Mo isotopic compositions may indicate compositional diversity in their sources or differences in magma evolution .
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FIBERS AND POLYMERS
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2020
·Vol. 21
·期 4
·762-774
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IF 1.797
Tan Zhenjiang,Gao Ming,Dai Jiangdong,Ge Wenna,Zhu Wenjing,Yan Yongsheng
Here, novel magnetic imprinted porous foams (MIFs) were prepared by Pickering oil-in-water high internal phase emulsion polymerization, using renewable cellulose nanocrystals (CNCs) derived from cotton source as the stabilizer, and surfactant Tween 85 and iron oxide magnetic nanoparticles as additive in aqueous phase, for selective adsorption of 4-nitrophenol (4-NP). Interconnected porous foam structure was formed and optimized by controlling the addition amount of solid stabilizer CNCs, Tween 85, and oil phase volume, the optimum value of which was 7.5 wt%, 5.0 wt%, and 85 %, respectively. The as-synthesized imprinted material had the good thermal stability and magnetic responsivity. The adsorption equilibrium data was fitted well by the Langmuir isothermal model with a maximum adsorption capacity of 287.5 µmol/g. Pseudo-second-order kinetics model could better describe the kinetics data. MIFs showed excellent selective ability for 4-NP as compared with these structural analogues. Besides, Thomas model explained the dynamic breakthrough curves better. The regeneration ability of MIFs was also satisfying after several reuse.
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MACROMOLECULES
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2020
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IF 5.918
Jia-Wei Long,Li Chen,Bo-Wen Liu,Xiao-Hui Shi,Xue-Bao Lin,Ying-Ming Li,Yu-Zhong Wang
The construction of novel semiaromatic polyamides (SaPAs) combining all advantages of aliphatic and aromatic polyamides is of particular importance in both academia and industrial circles. To study the effect of different pendent groups on the comprehensive properties of SaPAs, three kinds of SaPAs with different pendent groups were designed and prepared by the aromatic nucleophilic substitution polycondensation, named as P-PAH (dimethyl-), P-PEPH (methylphenyl-), and P-DPMPH (diphenyl-). All of these polyamides exhibited a relatively high molecular weight with narrow molecular weight distribution. It was found that the chain conformation of P-PEPH was significantly different from those of P-PAH and P-DPMPH due to the formation of the helical structures caused by the asymmetric methyl and phenyl pendent groups, which was testified by computational simulation. Meanwhile, SaPAs with phenyl pendent groups (P-PEPH and P-DPMPH) exhibited an interaction between molecular chains due to π–π stacking, as proved by wide-angle X-ray diffraction (WAXD) results. With an increase in the content of the phenyl pendent groups, their glass-transition temperatures (Tg) increased gradually from 135.6 to 156.5 °C and the initial decomposition temperatures (T5%) also increased. Rheological investigations and solubility tests showed that these polyamides were suitable for processing either in melt or in solution. The expected mechanical properties of P-PEPH were also obtained due to the unique chain conformation and π–π stacking. Taking these advantages, this kind of novel SaPAs exhibited potential availability in versatile applications.
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JOURNAL OF HAZARDOUS MATERIALS
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2020
·
IF 9.038
Xiang Li,Yan Jia,Minghua Zhou,Xianfa Su,Jianhui Sun
In this study, the Fe, N co-doped biochar (Fe-N-BC) was prepared by pyrolyzing wheat straw, urea and iron salts and used to activate persulfate (peroxydisulfate, PS) for organic contaminant degradation. Iron oxide doping not only introduced magnetism into the biochar for easy separation, but also influenced its catalytic ability for PS activation. In the Fe-N-BC/PS system, almost all acid orange (AO7) was removed within 90 min with an apparent rate constant ( k obs ) of 0.114 min −1 , which was almost 37 times larger than that of pure N-BC (0.003 min −1 ). Factors influencing the removal of AO7 were investigated, including PS concentration, catalyst dosage, and initial pH. The Fe-N-BC/PS system had high removal efficiencies for various organic contaminants and showed high resistance to inorganic anions in aquatic environments. The radical quenching studies, electron paramagnetic resonance (EPR) measurements, and electrochemical analyses verified that the mechanism of AO7 degradation in the Fe-N-BC/PS system included both radical and non-radical pathways involving the generation of OH, SO 4 − , O 2 − , 1 O 2 , and electron transfer. Additionally, persistent free radicals (PFRs) on the catalysts also related to their catalytic efficiencies. These results demonstrated that the Fe-N-BC/PS system had the potential for wastewater treatment applications.
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PubMed
高影响因子
ACS Applied Nano Materials
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2020
·
IF 0
Yun Shan,Hong-Lin Zhang,Yuan Zhu,Ying Wang,Huaju Song,Chuanguo Shi
An electrochemiluminescent immunosensor is constructed for the detection of diethylstilbestro (DES) on the basis of amplified quenching of electrochemiluminescence (ECL) from CdTe nanocrystal (NC)/reduced graphene oxide (rGO) composite films by antibody (Ab) against DES-modified SiO2 nanoparticles (Ab@SiO2). In this immunosensing system, CdTe NC/rGO composite films act as solid supporters for both DES and ECL emitters, which generate a 100-fold stronger ECL emission than CdTe NC films because the presence of rGO can lower the potential barrier, facilitate charge transfer, suppress nonradiative Auger recombination, and make the electron trap states fill more efficiently. On the composite films, the immobilized ovalbumin-modified DES (OVA-DES) competes with free target DES to bind Ab@SiO2. As a result, the number of formed OVA-DES-Ab@SiO2 immunocomplexes is inversely related to that of target DES. Using an ECL quenching maximum at blank as a calculation benchmark, the ECL intensity increment of the immunosensor and the concentration of target DES show a linear range of 0.002–2 ng/mL (R2 = 0.996) with a detection limit of 0.001 ng/mL (signal/noise = 3). This immunosensor, of good selectivity and stability, was used to detect beef samples, with recoveries at a scope of 93.2%–105.0%.
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JOURNAL OF CHROMATOGRAPHY A
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2020
·
IF 4.049
Tiemei Li,Yuefei Song,Zhaoqi Dong,Yueyue Shi,Jing Fan
ABSTRACT As a new kind of green solvents for potential replacement of traditional volatile organic compounds, deep eutectic solvents (DESs) have been attracting more and more attention in various applications. In this work, three types of hydrophobic DESs were synthesized by simple mixing of trioctylmethyl ammonium chloride (used as hydrogen bond acceptor) with decanoic acid, ketoprofen and gemfibrozil (hydrogen bond donors), respectively, at different molar ratios. In order to evaluate the solvent characteristics of these DESs, some of the physical properties such as melting point, density, viscosity, and water contact angle were determined. Then, these hydrophobic DESs were used for the vortex-assisted liquid-liquid microextraction of bisphenol-type contaminants in water, followed by quantitative determination of bisphenols contents with high performance liquid chromatography (HPLC-FLD) coupled with fluorescence detection. For this purpose, four bisphenols, namely, 2, 2-bis(4-hydroxydiphenyl)propane (BPA), 2, 2-bis (4-hydroxyphenyl)butane (BPB), 4, 4′-(1-phenylethylidene)bisphenol (BPAP) and 4, 4′-cyclohexylidenebisphenol (BPZ) were selected as model contaminants. It was found that the enrichment factors of the proposed method were in the range from 97 to 112, depending on the structure of the analytes. Under optimal experimental conditions, the linearity ranges of the method varied from 0.3 to 700 µg L −1 with linear correlation coefficients (R 2 ) higher than 0.996. The limit of detections (LODs) and limit of quantifications (LOQs) were in the range of 0.3-0.5 µg L −1 and 0.06-0.08 µg L −1 , respectively. Furthermore, the developed method was successfully used in the extraction and determination of four bisphenols from food-contacted plastic samples.
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高影响因子
JOURNAL OF MATERIALS SCIENCE
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2020
·Vol. 55
·期 27
·12921-12939
·
IF 3.553
He Yayue,Sun Shaofeng,Han Na,Zhang Xingxiang,Li Wei
Abstract Intelligent breathable membranes with multiple functions attach wide attentions of people which provide protection and comfort to meet the pressing demand for future protective clothing. We proposed a novel thermal energy regulated and thermochromic composite film with temperature-sensitive “breathable” stomata consisted of thermochromic nanofibrous membrane (TC-NFM) and thermo-sensitive polyurethane (PU) film. Thermochromic nanoencapsulated phase change materials (TC-NPCMs) were introduced as functional fillers into polyvinyl alcohol/water-soluble polyurethane (PVA/WPU) solution for electrospinning process. And methylated melamine–formaldehyde (MMF) was innovatively used to modify the water resistance of TC-NFM. By adjusting the molecular weight of the soft segment, the thermo-sensitive PU film was successfully prepared. Consequently, the prepared TC-NFM exhibited high enthalpy of 44.3 J g −1 and kept superior energy storage and release property even after 100th cyclic experiments. The water vapor permeability of thermo-sensitive PU film was triggered near the comfortable temperature of the human body. The results presented here might facilitate improvements in the field of thermal regulation clothing, intelligent clothing, wearable temperature sensor and reversible thermochromic coating materials. Graphic abstract
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APPLIED CATALYSIS B-ENVIRONMENTAL
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2020
·
IF 16.683
Cong Gao,Yan Su,Xie Quan,Virender K. Sharma,Shuo Chen,Hongtao Yu,Yaobin Zhang,Junfeng Niu
Heterogeneous Fenton-like reaction was a promising approach for generating •OH. However, the heterogeneous catalysts generally exhibited low activity because of slow reduction of Fe(III) in Fe(III)/Fe(II) redox cycle. Here, decreasing electron density was expected to quicken Fe(III) reduction and consequently enhance the catalytic activity of heterogeneous catalysts. This hypothesis was validated by the enhanced hydroxyl radicals generation and accelerated Fe(III) reduction on MIL-88B(Fe)-X (2-X-terephthalic acid, X = NH 2 , CH 3 , H, Br and NO 2 ) by reducing electron density of Fe(III) with substituent of higher electrophilicity. MIL-88B(Fe)-NO 2 , with the substituent of highest electrophilicity among these catalysts, has the lowest electron density of Fe(III) and highest redox potential ( E Fe(III)/Fe(II) = 0.35 V). As a result, it exhibited the best catalytic performance, which was 1.7–20 times higher than that for other MIL-88B(Fe)-X and was comparable to that of homogeneous Fe 2+ . This study provides scientific basis for rational construction of highly effective heterogeneous Fenton-like catalyst.
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Environmental Science and Ecotechnology
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2020
·
IF 0
Jing Ding,Lingjun Bu,Bingxin Cui,Guanshu Zhao,Qingwei Gao,Liangliang Wei,Qingliang Zhao,Dionysios D. Dionysiou
Bisphenol (BP) analogues in wastewater effluent and groundwater pose a potential threat to human health due to their ability to disrupt steroidogenesis. A new solar-assisted electrochemical process (SECP) was developed and evaluated for the degradation of BP analogues. The effects of quenchers, current density, initial pH, supporting electrolyte, and aqueous matrix on the removal kinetics of bisphenol AF (BPAF) and bisphenol A (BPA) were investigated. The kinetic constants of BPAF, BPA, and bisphenol S (BPS) in the SECP with irradiation intensity of 500 mW cm −2 were 0.017 ± 0.002 min −1 , 0.022 ± 0.002 min −1 , and 0.012 ± 0.001 min −1 , respectively. The changes in the degradation rates of BPAF, BPA, and BPS in the presence of quenchers indicated the relative contribution of hydroxyl radical ( ● OH) oxidation, anodic electrolysis, and singlet ( 1 O 2 ) oxygenation in the degradation of BPs in the SECP. The enhanced rate of generation of ● OH and 1 O 2 was observed in the SECP compared with those in the conventional electrochemical system. The identification of the transformation products (TPs) of BPAF demonstrated that hydroxylation, ring cleavage, β-scission, and defluorination were the major processes during the oxidation in the SECP. The conversion to fluoride ions (76%) and mineralization of total organic carbon (72%) in the SECP indicated further degradation of TPs. The results from this study improved our understanding of the degradation of BP analogues in the electrooxidation irradiated by solar light and help to establish the application potential of the SECP for the effective degradation of emerging contaminants in wastewater.
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PubMed
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Songxue Wang,Jiayu Tian,Zhihui Wang,Qiao Wang,Jialin Jia,Xiujuan Hao,Shanshan Gao,Fuyi Cui
A novel CuO modified ceramic hollow fiber membrane for in-situ peroxymonosulfate (PMS) activation was developed and employed in surface water treatment. The performance of membrane fouling control and organic pollutants removal was systematically investigated. The results indicated that compared with pristine membrane, CuO modified ceramic hollow fiber membrane significantly improved the removal of dissolved organic carbon (DOC) and UV absorbance at 254 nm (UV 254 ) in surface water. The removal rate increased with the increase of CuO loading content because of the reduction of the membrane surface pore size, but declined with the increase of PMS dosage due to the degradation products of incomplete mineralization passing through the membrane. The fluorescent compounds in surface water were efficiently removed by the CuO modified ceramic hollow fiber membrane and enhanced with the increase of PMS dosage and CuO loading content. The CuO modified ceramic hollow fiber membrane with in-situ PMS activation exhibits excellent antifouling property to natural organic matter (NOM) in surface water. Both the reversible and irreversible fouling decreased with the increase of PMS dosage while the membrane fouling would be slightly intensified with increased loading of CuO on the membrane, suggesting the trade-off relation between PMS dosage and CuO loading content. In addition, the degradation efficiency of organic pollutants in surface water was dramatically enhanced by the CuO modified ceramic hollow fiber membrane via incorporation of in-situ PMS oxidation process. High removal performance after five cycles of experiments showed the superior stability and reusability of the CuO modified ceramic hollow fiber membrane.
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NEW JOURNAL OF CHEMISTRY
·
2020
·Vol. 44
·期 16
·6355-6361
·
IF 3.288
Ling Jiang,Xiangyang Xu,Jingjing Yuan,Yuanjie Zuo,Yingrui Tao,Dachuan Yao,Guangyu He,Haiqun Chen
Spherical Ni2SnO4 nanoparticles were uniformly loaded on reduced graphene oxide (RGO) sheets via a hydrothermal process. The obtained nickel stannate–reduced graphene oxide (Ni2SnO4–RGO) composite was used as a catalyst for activating persulfate (PS). The heterostructure composed of Ni2SnO4 and RGO prevents both the agglomeration of Ni2SnO4 nanoparticles and the restacking of RGO sheets. The synergy between the two components affords enhanced Ni2SnO4–RGO catalytic activity. Using Ni2SnO4–RGO to activate PS can degrade bisphenol A (BPA) at a faster rate with less PS, in comparison with the most recently reported catalysts. BPA solution (50 mL, 0.10 mM) can be 100% degraded by PS (0.02 g) within 30 min at pH 8 using Ni2SnO4–RGO (0.02 g) as the catalyst. Moreover, the preparation of Ni2SnO4–RGO is simple, inexpensive and environment-friendly. The radical scavenging study indicates that sulfate radicals () and hydroxyl radicals (˙OH) are involved in the oxidation, in which plays a leading role. In addition, Ni2SnO4–RGO retains high catalytic activity after four consecutive cycles, exhibiting greatly enhanced stability in comparison with Ni2SnO4. Besides, the effect of different inorganic anions on the degradation was also explored.
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危险品化学品经营许可证（带存储）