RESEARCH ON CHEMICAL INTERMEDIATES
·
2020
·Vol. 46
·期 11
·5117-5131
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IF 2.262
Sun Li,Zhou Mingliang,Yin Zheng,Zhang Lixin,Dou Binlin,Su Wenxian
Abstract A green, rapid and controllable synthesis of gold nanoparticles (Au NPs) was achieved using the mulberry fruit (MF) extract as reducing and capping agent at room temperature. Obtained Au NPs were characterized by ultraviolet–visible spectrum, transmission electron microscopy, energy-dispersive X-ray spectroscopy, high-resolution transmission electron microscopy, selected area electron diffraction, X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy analyses. It could be found that Au NPs had a small size of 4.2–20.1 nm, face-centered cubic crystalline structure and homogeneous dispersion, indicating strong reducing and capping capacities of the MF extract. Meanwhile, the morphology (quasi-sphere/sphere) of Au NPs could be controlled only by adjusting the MF extract concentration. Furthermore, based on the 4-nitrophenol (4-NP) reduction reaction, as-prepared Au NPs exhibited excellent photocatalytic activity and stability in 30 days. Under sunlight irradiation, 4-NP could be completely reduced in 4 min and its rate constant could reach up to 0.91 min −1 . And the rate constant could be linearly adjusted by the MF extract concentration or the amount of Au NPs hydrosol. In addition, it could also be found that the light source with short wavelength could obviously elevate the photocatalytic activity of Au NPs, attributed to the hot-electron effect. Clearly, as-obtained Au NPs can have great potential applications in wastewater treatment. Graphic abstract
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SOLAR ENERGY
·
2019
·
IF 4.674
Wenhui Zhao,Xiaoyan Gan,Lili Ke,Liling Guo,Hanxing Liu
Two-dimensional layered organic-inorganic perovskite hybrids have attracted increasing attention due to their outstanding moisture resistance and promising optoelectronic properties. However, the photovoltaic performance in solar cells is still a huge challenge for two-dimensional perovskite films. With the aim to improve the efficiency of 2D perovskite solar cells, the new (ClC 6 H 4 C 2 H 4 NH 3 ) 2 MA n−1 Pb n I 3n+1 perovskite family (abbreviated as (CPEA) 2 MA n−1 Pb n I 3n+1 ) are synthesized by a simple one-step hot-casting method in this study. It is found that the variation of n value (n = 3–6) has great influence on the microstructure, grain size, charge mobility, trap density and photovoltaic performance of the 2D (CPEA) 2 (MA) n−1 Pb n I 3n+1 . Due to the best film quality and prolonged carrier lifetime, the (CPEA) 2 MA 4 Pb 5 I 16 (n = 5) perovskite solar cell exhibits a highest efficiency of 11.86%, with a V oc of 0.989 V, a J sc of 19.92 mA/cm 2 and FF of 60%, respectively. It is anticipated that our approach to explore new organic spacer cations in 2D perovskites may pave the way for their application with high performance.
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Sustainability
·
2022
·Vol. 14
·期 21
·14300
·
IF 3.889
Qinghong Wang,Siyu Li,Xin Wang,Zhuoyu Li,Yali Zhan,Chunmao Chen
The extensive use of pharmaceuticals and personal care products (PPCPs) causes high concentrations of pharmaceutical metabolites to exist in aquatic environments. Though the removal of parent PPCPs has raised concerns, the degradation of pharmaceutical metabolites was rarely investigated. In this study, the degradation of 4-acetylaminoantipyrine (4-AAA), a typical dipyrone metabolite frequently detected worldwide in surface water and wastewater, was initially studied using persulfate (PDS)-based advanced oxidation processes (AOPs). Compared with commonly used activation methods of alkali, ultrasonic, ultraviolet, and Fe2+, 4-AAA achieved its best degradation (98.9%) within 30 min in a thermally activated PDS system due to the promotion of both radical production and the reaction rate with the rise in temperature. The optimum degradation of 4-AAA could be achieved with the temperature of 80 °C regardless of initial pH values, indicating a wide suitable pH range. Moreover, over 80% of the degradation of 4-AAA could be achieved with the presence of Cl−(0–16 mM), HCO3−(0–8 mM), and humic acid (0–30 mg/L), further indicating the application potential of the system. Both sulfate radicals (SO4•−) and hydroxyl radicals (•OH) contributed to 4-AAA degradation and the contribution of •OH increased with the pH rising from 3 to 11 due to the transformation from SO4•−when reacting with OH−. Three hydroxylated and ring-opening intermediates were detected during the 4-AAA degradation. The ECOSAR prediction indicated that the acute toxicity of most intermediates decreased than 4-AAA while the chronic toxicity increased, which suggested the transformation of intermediates should be further focused on in SO4•−and •OH based AOPs. This study would provide technical reference for the control of 4-AAA in wastewater treatment processes, raise concerns on the influence of PPCPs metabolites, and throw light on reducing the harm of PPCPs and their metabolites in aquatic environments.Keywords:4-acetylaminoantipyrine (4-AAA);heat activation;persulfate;degradation pathway;toxicity
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INORGANIC CHEMISTRY COMMUNICATIONS
·
2022
·
IF 3.428
Jiashun Liang,Kaili Liang,Lifeng Li,Yuqi Cao,Xiong Cao
This paper investigates the effect of Fe 2 O 3 nanosheets as catalysts on the catalytic decomposition performance of DAP-4. Our laboratory has successfully fabricated Fe 2 O 3 nanosheets and DAP-4. The morphology and composition of DAP-4 and Fe 2 O 3 nanosheets were investigated using SEM, XRD and XPS. The catalytic decomposition performance of DAP-4 and DAP-4/Fe 2 O 3 nanosheets mixture samples were characterized by DSC. The results show that the synthesized Fe 2 O 3 nanosheets can reduce the activation energy of DAP-4, Fe 2 O 3 nanosheets have good catalytic activity. And calculate the relevant kinetic parameters for the mixed samples using the Kissinger equation.
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Fermentation-Basel
·
2023
·Vol. 9
·期 12
·998
·
IF 3.7
Yi Wei,Guangyao Mei,Jinlin Zhao,Shaoyang Zhang,Wenping Qin,Qing Sheng,Zhongyi Yang
Testosterone (TS) is an important androgen drug and a precursor of steroid drug synthesis. Ketoreductase 2 (KR-2) (GenBank accession no. ABP64403.1) is observed to stereo-selectively catalyze the bioreduction of 4-androstene-3,17-dione (4-AD) to testosterone and contribute to the regeneration of NADH using isopropanol as a co-substrate. The Km value of KR-2 was 2.22 mmol/L with 4-AD, and the optimal pH was 6.5–7.0. The enzyme is stable and demonstrates relatively high-level enzyme activity at 40 °C. Acetone significantly inhibits this activity. This inhibition was overcome using an intermittent vacuum during the reaction process. Finally, the amount of TS reached 65.42 g/L after a 52 h reaction with 65.8 g/L 4-AD, 10% isopropanol, and 2 g/L β–NAD+at 40 °C, with a conversion rate of 98.73%. A total of 6.15 g of TS was obtained from 6.58 g of 4-AD after the reaction and purification; the HPLC purity was 99.82%, and the overall yield was 92.81%. This enzyme provides a promising route for the green biosynthesis of testosterone for industrial applications.Keywords:testosterone;bifunctional ketoreductase;NADH regeneration;enzymatic synthesis
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ACS Applied Polymer Materials
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2023
·
IF 5
Siyuan Zhang,Jiao He,Xinjian Cheng
Amphiphilic hyperbranched polymers (AHBPs) possess important characteristics, such as high solubility, low viscosity, and multiple functional groups, making them of significant scientific interest. In this work, a chain transfer agent (CTA) with a styrene unit was synthesized at first. Subsequently, the CTA was polymerized with a coumarin derivative containing a −C=C bond through reversible addition-fragmentation chain transfer-self-condensing vinyl polymerization (RAFT-SCVP) to obtain the hyperbranched polymer HP-1. Finally, using HP-1 as a macromolecular CTA, amphiphilic hyperbranched fluorescent probes AHP-2 and AHP-3 were synthesized via RAFT polymerization of hydrophilic monomers poly[oligo(ethylene glycol) methacrylate] (PEGMA) and 2-(dimethylamino)ethyl methacrylate (DMAEMA). The as-prepared AHP-2 and AHP-3 were characterized and confirmed. These macromolecular fluorescent probes enable highly sensitive and specific recognition of 4-nitrophenol (4-NP) with detection limit as 0.59 μM. A unique fluorescence quenching effect, termed “enriching inner filter effect (IFE)”, was revealed through the study of the recognition mechanism of the probes for 4-NP in hyperbranched polymers. This effect has the potential to expand the preparation methods of both fluorescent probes and functional hyperbranched polymers. This work investigates the synthesis methodology of amphiphilic hyperbranched polymers and the performance of fluorescent probes, providing a valuable approach for the development of highly sensitive polymer fluorescent probes in the future.
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COMBUSTION AND FLAME
·
2023
·
IF 4.4
Erhai An,Yihong Tan,Kehua Han,Xiaoxia Li,Xiong Cao,Yingxin Tan,Peng Deng
Molecular perovskite energetic material DAP-4 is seen as a potential high-energy oxidant due to its high energy, high density, high oxidation capacity, and facile preparation technology. However, optimizing its energy release and reducing its thermal decomposition temperature are huge challenges for its future application. In this work, the role of iron (Fe) nanospheres in the energy release of DAP-4 was studied. Our research has shown that Fe powder can not only serve as a fuel to promote combustion, but also as an important catalyst to significantly improve the thermal decomposition, energy release, and burning rate of DAP-4. By adding 25% Fe nanospheres, the decomposition temperature of DAP-4 was reduced to 299.7 °C, which is the most reduction by 84.7 °C from 384.4 °C (raw DAP-4) to 299.7 °C (DAP-4/Fe-5 with 25wt% Fe nanospheres) was obtained. The decomposition activation energy also decreases by at least 69.5 kJ mol −1 from 229.4 kJ mol −1 (DAP-4) to 159.9 kJ mol −1 (DAP-4/Fe-1 with 5wt% Fe nanospheres). The combustion performance of DAP-4/Fe composites is significantly improved by a 4∼5 times shorter burn rate. The energy-releasing mechanism of DAP-4 with the presence of Fe nanospheres was proposed. Fe x O y at the surface of Fe nanospheres played an important role in the energy releasing of DAP-4. This work showed a new idea for the potential application of molecular perovskite energetic materials.
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ESC Heart Failure
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2023
·
IF 3.8
Yu Li,Qian He,Chao-Yong He,Chao Cai,Zhen Chen,Jing-Zhu Duan
Aims Diabetic cardiomyopathy (DC) is one of serious complications of diabetic patients. This study investigated the biological function of activating transcription factor 4 (ATF4) in DC. Methods and results Streptozotocin-treated mice and high glucose (HG)-exposed HL-1 cells were used as the in vivo and in vitro models of DC. Myocardial infarction (MI) was induced by left coronary artery ligation in mice. Cardiac functional parameters were detected by echocardiography. Target molecule expression was determined by real time quantitative PCR and western blotting. Cardiac fibrosis was observed by haematoxylin and eosin and Masson's staining. Cardiac apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick end labelling. Activities of superoxide dismutase, glutathione peroxidase, and levels of malonic dialdehyde and reactive oxygen species were used to assess oxidative stress damage. Molecular mechanisms were evaluated by chromatin immunoprecipitation, dual luciferase assay, and co-immunoprecipitation. ATF4 was up-regulated in the DC and MI mice ( P < 0.01). Down-regulation of ATF4 improved cardiac function as evidenced by changes in cardiac functional parameters ( P < 0.01), inhibited myocardial collagen I ( P < 0.001) and collagen III ( P < 0.001) expression, apoptosis ( P < 0.001), and oxidative stress ( P < 0.001) in diabetic mice. Collagen I ( P < 0.01) and collagen III ( P < 0.01) expression was increased in MI mice, which was reversed by ATF4 silencing ( P < 0.05). ATF4 depletion enhanced viability ( P < 0.01), repressed apoptosis ( P < 0.001), oxidative damage ( P < 0.001), and collagen I ( P < 0.001), and collagen III ( P < 0.001) expression of HG-stimulated HL-1 cells. ATF4 transcriptionally activated Smad ubiquitin regulatory factor 2 (Smurf2, P < 0.001) to promote ubiquitination and degradation of homeodomain interacting protein kinase-2 ( P < 0.001) and subsequently caused inactivation of nuclear factor erythroid 2-related factor 2/heme oxygenase 1 pathway ( P < 0.001). The inhibitory effects of ATF4 silencing on HG-induced apoptosis ( P < 0.01), oxidative injury ( P < 0.01), collagen I ( P < 0.001), and collagen III ( P < 0.001) expression were reversed by Smurf2 overexpression. Conclusions ATF4 facilitates diabetic cardiac fibrosis and oxidative stress by promoting Smurf2-mediated ubiquitination and degradation of homeodomain interacting protein kinase-2 and then inactivation of nuclear factor erythroid 2-related factor 2/heme oxygenase 1 pathway, suggesting ATF4 as a treatment target for DC.
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高影响因子
POLYMER
·
2018
·
IF 3.483
Yongjian Lou,Zhongxiang Zhao,Zhiwei Chen,Zenghui Dai,Feiya Fu,Yanyan Zhang,Lei Zhang,Xiangdong Liu
High melting temperature and viscosity of most benzoxazine monomers are challenging problems in processing, especially for preparation of composites. The present work introduces the “reactive diluent” concept to improve the processability of benzoxazines. A benzoxazine monomer having a vinyl group is first synthesized from 4-vinylguaiacol (4VG), and then dissolved in a reactive diluent, styrene or methyl methacrylate . The resulting solutions show low viscosity (less than 2 mPa s), and exhibit high reactivity during free radical and ring-opening polymerizations, successively. Furthermore, the solutions are applied to fabricate cotton fabrics reinforced composites. Both of them possess high glass transition temperature and excellent mechanical properties , which have potential applications as structural components.
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RSC Advances
·
2019
·Vol. 9
·期 17
·9449-9456
·
IF 3.049
Yuhua Zhang,Jiayi Jiang,Ningbo Qin,Qian Zhang,Chunyan Yan
Cambial meristematic cell (CMC) suspension cultures were investigated as a new biotransformation system for the first time. Four 4-methylcoumarins substrates were transformed by CMCs of Camptotheca acuminata into four corresponding products, including 4,8-dimethylcoumarin-7-O-β-D-glucopyranoside (I-1), 4,7-dimethylcoumarin-6-O-β-D-glucopyranoside (II-1), 6-hydroxy-7-methoxyl-4- methylcoumarin (III-1), and 4,7-dimethylcoumarin-5-O-β-D-glucopyranoside (IV-1), of which I-1, II-1, and IV-1 were new compounds. In addition, the biotransformation time and the amount of substrate were investigated to compare the biotransformation rate and optimize the biotransformation conditions of the four substrates in C. acuminata CMCs suspension cultures. The results suggested C. acuminata CMCs were able to select glycosylate phenolic hydroxyl groups of 4-methylcoumarins I, II, and IV, with high regio- and stereoselectivity, but no corresponding glycoside of any phenolic hydroxyl group of compound III was detected. Simultaneously, the result also showed that the C. acuminata CMCs were able to transform the 7-hydroxy groups of substrate III to its corresponding methylated products. Furthermore, the monoamine oxidase (MAO) inhibition activities of biotransformed products were evaluated, and the data showed that all the products possessed good MAO inhibition activities in vitro. In conclusion, C. acuminata CMCs could be applied to glycosylation biotransformation as a novel plant-based system due to the successful application of bioconversion of exogenous coumarins.
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ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2019
·Vol. 26
·期 9
·9161-9173
·
IF 2.914
Zhang Tingting,Yang Yanling,Li Xing,Wang Nan,Zhou Zhiwei
Ultrasound-assisted regeneration of powdered activated carbon (PAC) saturated with 4-chlorophenol (4-CP) was investigated in this work. The variables, i.e., acoustic frequency, density levels, regenerating solution species, spent PAC mass, and the number of repeated cycle, were optimized. The UV–Vis spectra, thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), and pore structure analysis were used to characterize the regenerated PAC as compared to the virgin and spent PAC. The adsorption experiments indicated that the adsorption kinetics of 4-CP fitted well with the pseudo-second-order model, and the main chemisorption process was nonlinear and heterogeneous. The desorption results showed that the optimized regenerated conditions were identified as 40 kHz of frequency, 0.18 W/mL of sonication intensity, 0.1 M NaOH and 50% ( v / v ) ethyl alcohol mixture of regeneration solution, and 1 g/L of saturated PAC mass. Under this condition, the regeneration efficiency reached up to 86.81%. Hydroxylated oxidation products especially benzoquinone and hydroquinone were formed during ultrasound regeneration. Ultrasound mainly acted on surface functionalities, mesopores, and macropores of PAC through the hydroxyl radical oxidization resulted from the cavitation effect.
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Chinese Physics B
·
2018
·Vol. 27
·期 6
·066108
·
IF 1.321
Qing Yu,Jiangjian Shi,Pengpeng Zhang,Linbao Guo,Xue Min,Yanhong Luo,Huijue Wu,Dongmei Li,Qingbo Meng
A study of the self-healing phenomenon of Cu2ZnSn(S, Se)4 (CZTSSe) solar cells has shown more than 10% enhancement in cell performance after storage at room temperature for a week, with a significant improvement in the open-circuit photovoltage (Voc) and fill factor (FF). In addition, up to 10.45% power conversion efficiency (PCE) has been achieved. No obvious change in crystallinity, crystal phase, optical absorption or elemental distribution in the CZTSSe films was detected on examining the x-ray diffraction (XRD) pattern, Raman spectrum, ultraviolet-visible (UV-Vis), and TOF-SIMS. Further investigations on the charge carrier concentration, charge radiative recombination, and band structure suggest that the enhancement in PCE stems mainly from a reduction in deep defects of the CZTSSe semiconductor film.
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危险品化学品经营许可证（带存储）