DYES AND PIGMENTS
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2022
·
IF 5.122
Zishuo Yi,Weiling Huang,Yan Xu
Dual-emitting ratiometric optical thermometers with the advantages of excellent self-calibration and high-sensitivity have become a research hot spot. Herein, a dual-emissive 4-methylumbelliferone encapsulated ZIF-8 (ZIF-8⊃4-MU) modified Zn 2 GeO 4 :Mn 2+ nanocomposite was simply prepared by adding Zn 2 GeO 4 :Mn 2+ nanorods into a methanol solution containing 4-methylumbelliferone (4-MU), zinc (II) nitrate hexahydrate, and 2-methylimidazole. Accompanying with the self-assembly of ZIF-8⊃4-MU, the binding affinity of Zn 2+ ions to the surface of Zn 2 GeO 4 :Mn 2+ nanorods enables the formation of ZIF-8⊃4-MU@Zn 2 GeO 4 :Mn 2+ nanocomposite. The photoluminescence violet-blue (420 nm) and green emissions (531 nm) of the nanocomposite can be ascribed to the two independent luminescent centers of 4-MU dyes confined in ZIF-8 and the characteristic transition of 4 T 1 - 6 A 1 for Mn 2+ ions doped in Zn 2 GeO 4 , respectively. The fluorescent intensity ratios (FIRs) of 4-MU to Mn 2+ (I 420 nm /I 531 nm ) showed excellent self-calibrating temperature monitoring functions with a maximum relative sensitivity (S r ) of 1.82%· o C −1 and stable reusability in the temperature range of 20–100 °C. Also, the ZIF-8⊃4-MU@Zn 2 GeO 4 :Mn 2+ hybridized polyvinyl alcohol (PVA) transparent film showed a similar multi-emitting behavior, as well as good processability and tensile properties . Benefiting from the excitation-dependent emitting property of ZIF-8⊃4-MU@Zn 2 GeO 4 :Mn 2+ , a multiple optical encryption of digital information was successfully realized based on a two-dimensional code, achieving an enhanced security level for preventing counterfeiting. This proof-of-concept study offers a feasible assembled way in fabricating multi-mode luminescent nanocomposites for ratiometric temperature sensing and information encryption .
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高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
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2020
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IF 2.888
Jinyi Chen,Hongxing Wang
Density and viscosity data of pure 3-chloro-4-fluoronitrobenzene and 3-chloro-2-fluoronitrobenzene were obtained in temperature range from 318.15 K to 348.15 K at the local atmospheric pressure of 99.7 kPa. The value of corresponding saturated vapour pressure of two isomers were determined in the temperature range of 409 K to 517 K. The relationship between temperature and density can be well correlated by the linear equation. The viscosity data was well described by the Litovitz, Ghatee, VFT, and Andrade equations, and the calculated value by the VFT equation is consistent with the measured data. Both the Antoine and Riedel equations can accurately describe the relationship between saturated vapour pressure and temperature of 3-chloro-4-fluoronitrobenzene and 3-chloro-2-fluoronitrobenzene, which can meet the requirements for chemical design. In addition, the thermal expansion coefficient was determined based on the density data, and the molar vaporisation enthalpy of two isomers was evaluated using the Clausius-Clapeyron equation.
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ACS Sustainable Chemistry & Engineering
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2021
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IF 8.198
Yue Zou,Ang Fu,Jing Zhang,Tianpeng Jiao,Yong Yang,Jianming Zheng
To achieve higher energy density, LiCoO2 (LCO) is being developed for high-voltage operation at raised charge cutoff voltages up to 4.6 V vs Li/Li+, which however is beyond the electrochemical stability window of carbonate-based electrolytes. In this work, a novel electrolyte additive 2,4,6-tris(4-fluorophenyl)boroxin (TFPB) is proposed for enhancing the interfacial stability of LCO. Thanks to the TFPB additive, the LCO cathode exhibits substantially improved capacity retention of 84.6% after 200 cycles at 1C at a high charge cutoff of 4.6 V, surpassing the 63.2% attained in the baseline electrolyte. The improved performance could be rationalized by the fact that TFPB additive is preferentially oxidized to build a uniform and protective B–O bond-containing cathode–electrolyte interphase, contributing to the reduced parasitic side reactions, inhibited surface structural transformation, and better-maintained interfacial lithium-ion diffusion kinetics.
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高影响因子
Frontiers of Chemical Science and Engineering
·
2021
·Vol. 16
·期 7
·1090-1100
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IF 4.204
Wen Yong-Hui,Cheng Long,Xu Tian-Ming,Liu Xing-Hai,Wu Ning-Jie
Twenty six novel pyrimidin-4-amine derivatives containing the 1,2,4-oxadiazole motif were synthesized. Their chemical structures were confirmed by 1 H nuclear magnetic resonance (NMR), 13 C NMR, and highresolution mass spectrography. The insecticidal activity results indicated that some of them possessed excellent insecticidal activity (100%) against Mythimna separate , especially for compounds 6d, 6f, 6o, 6w, 6y and 6z . These compounds exhibited no activity against the insects Aphis medicagini and Tetranychus cinnabarinus . The structure-insecticidal activity relationships are discussed. Density functional theory analysis can potentially be used to design more active compounds. These results provide useful insecticide design information for further optimization.
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高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
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2014
·Vol. 16
·期 8
·1-8
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IF 2.278
Ren Yanlin,Zhao Qidong,Li Xinyong,Xiong Wei,Tade Moses,Liu Lihong
A novel visible-light-activated photocatalyst consisting of porous graphitic C 3 N 4 nanosheets and Ag 3 PO 4 nanoparticles were synthesized through a tunable in situ deposition method. The morphology and microstructure of the C 3 N 4 /Ag 3 PO 4 nanocomposites were carefully characterized by scanning electron microscope, TEM, X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDX), X-ray photoelectron spectra, and so on. The porous C 3 N 4 /Ag 3 PO 4 nanocomposites were featured by the typical platelet-like morphology, with an average crystallite size of about 39 nm. The coexistence of porous graphitic C 3 N 4 nanosheets and Ag 3 PO 4 nanoparticles is confirmed via the XRD and EDX results. Owing to its narrower band gap of Ag 3 PO 4 , the nanocomposites displayed a significant redshift of UV–Vis spectral absorption edge together with expanded light absorption in comparison with g-C 3 N 4 nanosheets. The photocatalytic activity of the prepared C 3 N 4 /Ag 3 PO 4 nanocomposites is demonstrated by the photodegradation of 4-chlorophenol (4-CP). The C 3 N 4 /Ag 3 PO 4 nanocomposites displayed higher photocatalytic activity than pure C 3 N 4 or Ag 3 PO 4 , which could be attributed to the interfacial effect of the nanocomposites in inhibiting the unfavorable recombination of photogenerated electrons and holes. Electron spin resonance spin-trap study implied that the generation of hydroxyl radicals plays the key role in the photodegradation of 4-CP by the C 3 N 4 /Ag 3 PO 4 nanocomposites under visible light irradiation.
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JOURNAL OF FLUORESCENCE
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2025
·
IF 3.1
Tang Qianyun,Huang Linling,Chen Tingting,Xie Feifei,Tan Hongyan,Chen Donghua
In this paper, a molecular imprinted metal-organic framework was prepared by a simple one-pot method using lanthanide terbium ions as the metal source, 2-aminoterephthalic acid as the organic ligand, and 4-nitrophenol as the template molecule at 120 °C. The materials of imprinted and non-imprinted metal-organic framework were characterized and analyzed by Scanning Electron Microscope, X-ray photoelectron spectroscopy, X-ray Diffraction, Brunauer-Emmett-Teller Specific Surface Area Analysis and fluorescence methods, etc., respectively. The fluorescence of the imprinted metal-organic framework was quenched by 4-nitrophenol in water, and there was a linear correlation between the fluorescence quenching efficiency of molecular imprinted metal-organic framework and the logarithm of 4-nitrophenol concentration in the range of 10–500 µmol L − 1 . The limit of detection was 3.3 µmol L − 1 (3σ) and the limit of quantitation was 11.0 µmol L − 1 (10σ). The molecular imprinted metal-organic framework was used for the determination of 4-nitrophenol concentration in water samples with the recoveries of 93.5-102.9% and the relative standard deviations less than 3.63%. The molecular imprinted metal-organic framework has the advantages of easy preparation, high stability, good sensitivity and selectivity, which has potential application for the detection of 4-nitrophenol in the environment samples. Graphical abstract
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高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2025
·
IF 6.2
Yihan Chen,Wanqing Wei,Jianhao Xu,Wei Song,Jian Wen,Guipeng Hu,Xiaomin Li,Cong Gao,Jing Wu
3-Hydroxy-3-methylbutyrate (HMB), an important dietary supplement, can enhance the quality of life for sedentary and elderly people. However, the catalytic efficiency of the pathway enzymes limited the biosynthesis of HMB. Here, we identified an efficient 4-hydroxyphenylpyruvate dioxygenase (4-HPPD) from Bacteroides barnesiae (BbHPPD) that converted l-Leucine (l-Leu) to HMB together with an efficient L-amino acid deaminase (L-AAD) in lab-preserved Proteus mirabilis (PmL-AADQ92A). The regioselective hydroxylation mechanism of the decarboxylated intermediate of 4-methyl-2-oxopentanoic acid (α-KIC) catalyzed by BbHPPD was elucidated for the first time. Structure-guided semirational design of BbHPPD generated a mutant M4. Compared to the wild type, the titer of mutant M4 increased by 254% when using α-KIC as a substrate. Finally, the engineered Escherichia coli 06 strain achieved the HMB titer of 11.6 g/L, a molar conversion of 65%, and a space-time yield of 0.64 g/(L·h) (the highest to date) in 18 h. This study lays the foundation for industrial-scale biosynthesis of HMB.
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高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2025
·
IF 4
Zhu Yu,Wen Shuai,Li Hui,Zhuang Tao,Li Lu,Liu Qiang,Yan Shou-Ke
Living cationic polymerization of 4-acetoxystyrene (STO) was conducted in CH 2 Cl 2 at −15 °C using a dicumyl chloride (DCC)/SnCl 4 / n -Bu 4 NBr initiating system. Impurity moisture initiation was inhibited by adding proton trap 2,6-di-tert-butylpyridine (DTBP), and the controlled initiation of DCC was confirmed by 1 H nuclear magnetic resonance ( 1 H-NMR) spectroscopy and matrix-assisted laser desorption ionization time-of-flight mass (MALDI-TOF-MS) spectrometry. The polymerization kinetics were analyzed to for optimizing the polymerization rate. Allyl-telechelic PSTOs (allyl-PSTO-allyl) with molecular weight ( M n ) range of 3540–7800 g/mol and narrow molecular weight dispersity ( M w / M n ) about 1.25 were prepared through nucleophilic substitution with allyltrimethylsilane (ATMS) at approximately 40% monomer conversion. The experimental results indicate that the substitution efficiency of ATMS increased with higher ATMS concentration, temperature, and extended reaction time. Nearly unity ally-functionality for allyl-PSTO-allyl was achieved by adding sufficient SnCl 4 prior to the substitution.
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高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Yao Yu,Zhifeng Zhang,Yijun Cao,Wei Sun,Zhiyong Gao,Haisheng Han,Pan Chen,Jian Cao
To improve the separation of ilmenite from its associated gangue mineral titanaugite through selective flotation, a novel hydroxamic acid derivative, N-hydroxy-3-(4-methoxyphenyl) acrylamide (HMPA), was successfully synthesized and evaluated as an efficient collector. Comparative flotation tests demonstrated that HMPA outperformed conventional sodium oleate, achieving superior separation efficiency with a TiO 2 concentrate grade of 48.95 % and an impressive recovery rate of 76.0 %. To understand the underlying mechanisms, the interactions between HMPA and the mineral surfaces were investigated meticulously by adsorption capacity tests, contact angle analysis, FTIR, and XPS. The results of contact angle and adsorption measurements intuitively revealed that HMPA exhibited significantly greater adsorption capacity on the ilmenite surface compared to titanaugite. FTIR and XPS analyses indicated that HMPA adsorbed strongly onto the ilmenite surface through chelation with reactive Ti and Fe sites. Density functional theory (DFT) calculations further suggested that HMPA could act as a bidentate ligand, forming a stable five-membered chelate structure through interactions with the Ti and Fe active sites on the ilmenite surface. In conclusion, HMPA demonstrated outstanding collecting ability and selectivity, making it a highly promising collector for ilmenite flotation.
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高影响因子
FOOD AND CHEMICAL TOXICOLOGY
·
2025
·
IF 3.5
Yue Che,Xiaozhu Wang,Qian Li,Xiyi Peng,Zhen Liu,Wenhui Xu,Mei Jing,Ting Wang,Jian Gao,Weiling Wang
A B S T R A C T Exposure to 4-vinylcyclohexene diepoxide (VCD) has been associated to reproductive toxicity, However, the dynamic ovarian function alterations over time in rats and the underlying mechanisms remain unclear. This study investigated the effects of VCD on ovarian function in female Sprague-Dawley (SD) rats on the 25, 60 and 135 days after VCD injection and discovered related mechanisms. Our results showed that VCD had little ovotoxicity on the 25 th day, as no significant changes were observed except for the reduction of preantral follicles. However, on the 60 th day and 135 th day, rats exhibited irregular estrous cycles, abnormal serum sex hormone levels, ovarian morphological damage, decreased primordial and preantral follicles, and increased atretic follicles. We further found that on the 60 th and 135 th day, VCD might exert ovotoxicity by decreasing antioxidant enzyme levels, inhibiting of the Kelch-like ECH-associated protein 1 (KEAP1)/nuclear factor erythroid 2-related factor 2 (NRF2) and PTEN-induced putative kinase 1 (PINK1)/E3 ubiquitin ligase (Parkin) signaling pathway. Interestingly, on the 25 th day, KEAP1/NRF2 and PINK1/Parking signaling pathway were activated. This study provided a wider application in using laboratory rodents as a model of ovarian failure and highlighted that VCD-induced ovotoxicity was linked to the regulation of the KEAP1/NRF2 and PINK1/Parkin signaling pathways.
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高影响因子
Small
·
2025
·
IF 12.1
Shuhan Chen,Jichang Sun,Chun Chen,Pengyu Meng,Liansheng Li,Qinghua Liang
Aqueous zinc-ion hybrid capacitors (ZIHCs) are emerging as promising energy storage devices owing to several desirable attributes including good safety, high power density, and good stability. However, the limited energy density mainly caused by the low specific capacity of porous carbon cathodes hinders the practical application of ZIHCs. A Ce 3+/4+ redox couple-promoted aqueous ZIHC (Ce-ZIHC) is designed with the addition of Ce 3+/4+ electrolyte additives. The Ce 3+/4+ redox couple is shown to markedly increase the specific capacity of the porous carbon cathode energy and enhance the stability of Zn 2+ stripping/plating at the Zn metal anode. Notably, the as-constructed Ce-ZIHC performs more than twice the energy density of the ZIHC with the commercial activated carbon cathode. Furthermore, the Ce-ZIHC shows a low self-discharge rate and can work stably for more than 60 000 cycles at 5.0 A g −1 . This work highlights the great potential of Ce 3+/4+ redox couple in improving the overall performance of ZIHCs toward practical application.
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高影响因子
Catalysis Science & Technology
·
2024
·
IF 4.4
Jinsong Song,Chuanhua Zhou,Xi Chen,Yang Gu,Feng Xue,Qiaqing Wu,Dunming Zhu
Cyanate-mediated epoxide ring-opening by halohydrin dehalogenases (HHDHs) is a promising method for the synthesis of important optically pure 2-oxazolidinones. However, the regio- and stereoselectivity of the naturally occurring HHDHs are still not satisfactory for styrene oxides (SOs). We used a structure-guided semi-rational design to improve the selectivity of HHDHs from Ilumatobacter coccineus (IcHheG), followed by site-saturation and combinatorial mutagenesis of Y18, L103, I104, and N196. The double mutant I104F/N196W showed dramatically improved selectivity toward SOs with excellent regioselectivity (>99 : 1) and stereoselectivity (E > 200), producing the corresponding useful and valuable (S)-4-aryl-2-oxazolidinone and (S)-SO with 98% ee. Moreover, it accepted a wider range of styrene oxides with moderate to excellent selectivity. Analysis of the substrate binding conformations showed that the regio- and stereoselectivity improvement in IcHheG was attributed to an increase of geometric distances to the two carbons and the oxygen atom of the epoxide ring for a single stereoisomer. This study elucidated key structural motifs responsible for regulating the regio- and stereoselectivity of IcHheG, offering theoretical guidance for protein engineering of HHDHs from other organisms.
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