Journal of Advanced Ceramics
·
2022
·Vol. 11
·期 3
·392-402
·
IF 11.534
Feng Chao,Zhou Xu,Tao Bingjing,Wu Haitao,Huang Shifeng
Dense microwave dielectric ceramics of Ce 2 [Zr 1 − x (Al 1/2 Ta 1/2 ) x ] 3 (MoO 4 ) 9 (CZMAT) ( x = 0.02–0.10) were prepared by the conventional solid-state route. The effects of (Al 1/2 Ta 1/2 ) 4+ on their microstructures, sintering behaviors, and microwave dielectric properties were systematically investigated. On the basis of the X-ray diffraction (XRD) results, all the samples were matched well with Pr 2 Zr 3 (MoO 4 ) 9 structures, which belonged to the space group \(R\bar 3c\) . The lattice parameters were obtained using the Rietveld refinement method. The correlations between the chemical bond parameters and microwave dielectric properties were calculated and analyzed by using the Phillips—Van Vechten—Levine (P—V—L) theory. Excellent dielectric properties of Ce 2 [Zr 0.94 (Al 1/2 Ta 1/2 ) 0.06 ] 3 (MoO 4 ) 9 with a relative permittivity ( ε r ) of 10.46, quality factor ( Q × f ) of 83,796 GHz, and temperature coefficient of resonant frequency ( τ f ) of −11.50 ppm/°C were achieved at 850 °C.
研究领域:
材料科学
·
陶瓷
·
微波介电材料
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DOI
高影响因子
APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2021
·Vol. 195
·期 4
·2432-2450
·
IF 2.926
Zhang Yueqi,Ding Liping,Yan Zhenzhen,Zhou Dandan,Jiang Junwei,Qiu Jiarong,Xin Zhihong
An alkaline esterase, designated as EstXT1, was identified through functional screening from a metagenomic library. Sequence analysis revealed that EstXT1 belonged to the family VIII carboxylesterases and contained a characteristic conserved S-x-x-K motif and a deduced catalytic triad Ser56-Lys59-Tyr165. EstXT1 exhibited the strongest activity toward methyl ferulate at pH 8.0 and temperature 55°C and retained over 80% of its original activity after incubation in the pH range of 7.0–10.6 buffers. Biochemical characterization of the recombinant enzyme showed that it was activated by Zn 2+ and Co 2+ metal ion, while inhibited by Cu 2+ and CTAB. EstXT1 exhibited significant promiscuous acyltransferase activity preferred to the acylation of benzyl alcohol acceptor using short-chain p NP-esters (C2-C8) as acyl-donors. A structure–function analysis indicated that a WAG motif is essential to acyltransferase activity. This is the first report example that WAG motif plays a pivotal role in acyltransferase activity in family VIII carboxylesterases beside WGG motif. Further experiment indicated that EstXT1 successfully acylated cyanidin-3-O-glucoside in aqueous solution. The results from the current investigation provided new insights for the family VIII carboxylesterase and lay a foundation for the potential applications of EstXT1 in food and biotechnology fields.
研究领域:
生物化学
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生物技术
·
酶学
·
食品科学
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DOI
PubMed
高影响因子
HIGH PERFORMANCE POLYMERS
·
2023
·
IF 2.1
Jinshui Lu,Jinyuan Zhang,Heng Liu,Weipeng Chen,Jiangrong Luo,Ziqing Wang,Tingting Cui,Yonggang Min,Yidong Liu
In this work, a new diamine was designed by connecting flexible structures such as ether bond and aliphatic carbon chain between benzene rings, and was synthesized and purified through simple reactions such as Suzuki reaction. Finally, a series of polyimide (PI) films were synthesized by copolymerization with 4.4`-diaminodiphenyl ether (ODA)\pyromellitic dianhydride (PMDA) in different proportions. We prepared polyimide films with new monomer copolymerization ratios of 1% (PI-1), 5% (PI-2), 10% (PI-3), and 20% (PI-4). The polyimide films showed excellent glass transition temperatures, which were attributed to their unique bent architectures. The mechanical and thermal properties of the thermosets were studied using tensile testing, static thermomechanical analysis (TMA), and thermogravimetric analysis (TGA). As the results, the films exhibited the optimal glass transition temperatures (317.56°C–381.91°C), and the component with the highest copolymerization ratio has a 15% decrease in glass transition temperature compared to the component without copolymerization. Moreover, PI-1-PI-4 showed good heat resistance in the N2 atmosphere. The temperatures corresponding to a 5% heat loss in the films (T5%) were 458.12 °C–548.75°C, respectively.
研究领域:
材料科学
·
高分子化学
·
热分析
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DOI
高影响因子
ORGANIC ELECTRONICS
·
2019
·
IF 3.495
Tongchao Chu,Xiuping Ju,Xiao Han,Hongmei Du,Yan Zhang,Jinsheng Zhao,Junhong Zhang
Three novel electrochromic copolymers PTPE-1, PTPE-2, and PTPE-3 were synthesized by changing the ratio of donor to acceptor using the Stille coupling polymerization . 5,8,14,17-tetrabromoquinoxaline[2′,3':9,10]phenanthro[4,5-abc] phenazine (monomer b) was first introduced and employed as multi-functionalized unit with bisquinoxaline structure and high planarity, which was used as the acceptor unit. Two electron-rich monomers ProDOT-decyl 2 (monomer a) and thiophene (monomer c) are selected as the co-monomers and donor units. The three polymers were tested by X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), spectro-electrochemistry, kinetics, thermogravimetric analysis (TG), etc. All three polymers have narrow band gaps of lower than 1.85 eV and satisfactory thermal stability. As to electrochromic switching properties, the polymers showed high optical contrast and fast response time both in the visible and near-infrared regions. The optical contrasts are 53.35% at 540 nm and 66.49% at 1325 nm for PTPE-3, and its coloration efficiencies are 163 cm 2 C −1 at 540 nm, 205 cm 2 C −1 at 1325 nm, with fast switch time of less than 1 s. The color changes of three polymers were diversified and distinct, PTPE-1 changes from chestnut color to blue-gray color, PTPE-2 changes from dull red color to wathet color and PTPE-3 changes from deep red color to light blue-gray color. The excellent properties of the polymers might result from their cross-linked structure and consequent formation of the compatible ion transport channel.
研究领域:
材料科学
·
电化学
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DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 12
·6972-6980
·
IF 3.108
Xiaohui Liu,Qian Zhu,Qiuyan Zhang,Yanguang Zhang,Chen Ding
Over the past few years, ionic liquids (ILs) have been widely reported as reaction media for reverse atom transfer radical polymerization (ATRP). In particular, almost all the ILs with the structure [Hmim][RCOO] (R represents an alkyl group) have been used as ligands for a reverse ATRP system. However, the facile, simple and low-cost ILs, 1-alkyl-3-methylimidazole chloride ([Rmim][Cl]), have rarely been employed as ligands for reverse ATRP. In this article, a [Rmim][Cl] was successfully employed as a ligand for the reverse ATRP of methyl methacrylate with Fe(III) as catalyst and 2,2′-azobisisobutyronitrile as initiator. The key to success is to adjust the FeCl3/[Rmim][Cl] molar ratio value to 1 : 1. The results indicated that the polymerization with [Rmim][Cl] as a ligand proceeded in a controlled/“living” fashion, as evidenced by the first-order kinetic plot, low polydispersity index values, and increase in polymer molecular weight with monomer conversion. The effects of various experimental parameters, including different catalysts, reaction temperatures, solvents, and molar ratios of FeCl3/[Rmim][Cl], on the polymerization were investigated in detail. Furthermore, 1H NMR and gel permeation chromatography analyses confirmed the halogen-containing chain-end functionality of the resultant polymer.
研究领域:
高分子化学
·
有机合成
·
催化化学
·
功能材料
·
可控自由基聚合
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DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2023
·Vol. 106
·期 11
·6577-6585
·
IF 3.9
Yuting Zhang,Huan Tu,Guoying Zhao,Jingshan Hou,Yufeng Liu,Xin Qiao,Zhongzhi Wang,Bo Li,Ji-Guang Li,Feng Wang,Yongzheng Fang
Compared with other fluorescent crystal phases, garnet has better structural stability in a glass matrix and renders precisely controllable emissions due to the abundant lattice control positions. In this work, we regulate the coordination field of Ce 3+ ion based on the co-substitution method and achieve the spectra regulation in the yellow–green range. We used Ba 2+ –Si 4+ cations to replace Y 3+ –Al 3+ cations in Y 3 Al 5 O 12 (YAG) matrix to obtain blue-shift of the emission peak from 552 to 539 nm. The centroid shift and crystal field splitting decrease with the decreasing covalency of the bond between the Ce 3+ ion and the surrounding anions owing to the higher electronegativity of Si 4+ ions than Al 3+ ions. The corresponding fluorescent films were prepared by a low-temperature co-sintering process based on the as-made Ba 2+ –Si 4+ co-substituted phosphor. X-ray powder diffractometer and scanning electron microscopy images showed that the fluorescence crystals were less eroded and evenly dispersed in the glass matrix. Spectral analysis showed that the garnet phase was protected by using lead-free borosilicate glass with a low melting point, and the quantum efficiency of phosphor-in-glass (PiG) retains 98% of the corresponding phosphor. By adjusting the ratio of garnet phosphor to commercial red nitride phosphors, a warm white fluorescence with a color rendering index of 80.3 and color temperature of 3899 K was obtained. The prepared warm white film has potential application value in the whole spectra field.
研究领域:
材料科学
·
光电子学
·
固态照明
·
无机化学
·
晶体场理论
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DOI
高影响因子
Food Science & Nutrition
·
2024
·
IF 3.5
Jialing Lin,Chuanhui Zeng,Xueli Li,Qin Tang,Jing Liao,Yan Jiang,Xianchun Zeng
Heterocyclic amines (HAs) are a group of mutagenic and carcinogenic compounds produced from the processing of high-protein foods, which include 2-amino-3-methylimidazo[4, 5-f]quinoline (IQ) showing the strongest carcinogenic effect. Camels are able to digest HAs in foods, which provide rich microbial resources for the study. Thus, camel rumen and intestinal microbiota were used to degrade IQ, and the dominant microorganisms and their degradation characteristics were investigated. After three generations of culture with IQ as the sole carbon source, the highest abundance in rumen and intestinal microbes was found in the Proteobacteria phylum. The strains of third generation of the rumen contents were mainly attributed to the genera Brevundimonas and Pseudomonas , and the dominant genera in intestine were Ochrobactrum , Bacillus , and Pseudomonas . Microorganisms were further isolated and purified from the third generation cultures. These 27 strains from the rumen (L1–L27) and 23 strains from the intestine (C1–C23) were obtained. Among them, four strains with the most effective degrading abilities were as follows: L6 (28.55% of IQ degrading rate) and C1 (25.19%) belonged to the genus Ochrobactrum , L15 (23.41%) belonged to the genus Pseudomonas , and C16 (20.89%) were of the genus Bacillus . This study suggested the application of abundant microbial resources from camels' digestive tract to biodegrade foodborne toxins.
研究领域:
微生物学
·
环境科学
·
食品科学
·
毒理学
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DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
·
2026
·
IF 5.9
Qiwei Zhong,Yueyang Liu,Jiayu Song,Yuchao Cui,Haozhe Li,Li Zhao
Fe/Ti co-doping converts the P2 phase to the OP4 phase and suppresses the undesirable P2-O2 phase transition. • Fe/Ti co-doping breaks the Na + /vacancy ordering and improves sodium ion transport capability. • Ti doping can shorten the TM-O bonds and lengthen the Na-O bonds. P2-type Na 2/3 Ni 1/3 Mn 2/3 O 2 is regarded as a promising cathode material for sodium-ion batteries owing to its high specific capacity and low cost. Nevertheless, its practical application is hindered by irreversible structural degradation and rapid capacity decay associated with the detrimental P2–O2 phase transition during deep Na + extraction. In this work, Fe and Ti are co-incorporated into Na 2/3 Ni 1/3 Mn 2/3 O 2 via a sol-gel method to enhance structural stability. Rietveld refinement of X-ray diffraction (XRD) patterns indicates that Ti doping shortens TM–O bonds and enlarges Na + diffusion channels by increasing Na-O distances, thereby enhancing structural stability and Na + transport kinetics. In situ XRD analyses reveal that Fe/Ti co-doping regulates the phase transition pathway from the irreversible P2–O2 phase transition to a reversible P2–OP4 phase transition, effectively mitigating structural degradation during cycling. Electrochemical measurements demonstrate that optimized Fe/Ti co-doping enhances the overall electrochemical performance. The optimized composition, Na 2/3 Ni 1/4 Fe 1/12 Mn 7/12 Ti 1/12 O 2 , exhibits excellent cycling stability with a capacity retention of 82.33% after 50 cycles at 0.2 C, and delivers a specific capacity of 61.43 mA h g −1 at a high rate of 5 C. This study demonstrates that the combination of sol-gel synthesis and co-doping engineering provides an effective strategy for designing high-performance cathode materials for sodium-ion batteries.
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2017
·
IF 7.504
Daqin Chen,Gaoliang Fang,Xiao Chen
Tunability of emitting colors of perovskite quantum dots (PQDs) was generally realized via composition/size modulation. Due to their bandgap absorption and ionic crystal features, the mixing of multiple PQDs inevitably suffers from reabsorption and anion-exchange effects. Herein, we address these issues with high-content Mn2+-doped CsPbCl3 PQDs that can yield blue-excitable orange Mn2+ emission benefited from exciton-to-Mn energy transfer and Cl-to-Br anion exchange. Silica-coating was applied to improve air stability of PQDs, suppress the loss of Mn2+, and avoid anion-exchange between different PQDs. As a direct benefit of intense multicolor emissions from Mn2+-doped PQD@SiO2 solid phosphors, a prototype white light-emitting diode with excellent optical performance and superior light stability was constructed using green CsPbBr3@SiO2 and orange Mn: CsPb(Cl/Br)3@SiO2 composites as color converters, verifying their potential applications in the field of optoelectronics.
研究领域:
材料科学
·
光电技术
·
纳米技术
·
光子学
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DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2021
·
IF 5.279
Hao-Min Song,Li-Xia Zhao,Shuai-Qi Zhang,Tong Ye,Ying Fu,Fei Ye
Cinnamic acid, isolated from cinnamon bark, is a natural product with excellent bioactivity, and it effectively binds with cyclohexanedione to form novel 4-hydroxyphenylpyruvate dioxygenase (HPPD) inhibitors. According to the active sub-structure combination principle, a series of novel 3-hydroxy-2-cinnamoyl-2-en-1-one derivatives were designed and synthesized. The title compounds were characterized by infrared, 1H NMR, 13C NMR, and HRMS. The in vitro inhibitory activity of AtHPPD verified that compound II-13 showed the most activity with a half-maximal inhibitory concentration (IC50) value of 0.180 μM, which was superior to that of mesotrione (0.206 μM) in vitro. The preliminary herbicidal activity tests demonstrated that some compounds had good herbicidal activity especially compound II-13 at a concentration of 150 g ai/ha. The binding mode of AtHPPD through molecular docking indicated that two oxygens of compounds II-13 formed bidentate interactions with metal ions, and the benzene ring formed π-π accumulation effects with Phe-381 and Phe-424. The results of molecular dynamics simulations showed that compound II-13 exhibited a more stable binding ability with AtHPPD than mesotrione. This study provided insights into the development of natural and efficient herbicides in the future.
研究领域:
化学
·
药理学
·
农业科学
·
分子生物学
·
植物科学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Wei Wan,Xinxin Han,Yayun Zhou,Fangrui Chen,Xiping Jing,Shi Ye
Developing a secure and unclonable anti-counterfeiting technology with more dimensional encryptions is urgently demanded. All-inorganic halide perovskites hold great potential for applications in advanced fluorescence anti-counterfeiting owing to their superior optical properties, such as tunable emission colors, narrow emission peaks, etc. By further utilizing the feasibility of anion exchange for perovskite halides, this research successfully designs five-dimensional (5D) anti-counterfeiting barcodes with core–shell-like structured perovskite-like oxide and perovskite halide composites. The composites are prepared by a facile synthesis method, which includes adhesive growth of Cs(Pb x Mn 1-x )(Cl y Br 1-y ) 3 on the surface of CsCa 2 Ta 3 O 10 : Yb, Er (abbreviated as CCTO: Yb, Er@CsMX 3 ) via sharing Cs + at the interface. The unique structure makes it possess sensitivity to some additive decrypted inks, offering one more intriguing anti-counterfeiting dimension beyond the common dual-mode fluorescence and time-gating technique. The CCTO: Yb, Er@CsMX 3 composites exhibit typical green upconversion (UC) luminescence under a 980 nm laser, red or green or blue (RGB) emission under ultraviolet (UV) light irradiation, ns-ms emission decay time, and changeable emission color when treated with decrypted inks. The fluorescent inks and barcodes are simple for fabrication, efficient for coding, easy for viewing and difficult for cloning, making them promising for anti-counterfeiting applications.
研究领域:
材料科学
·
光学
·
纳米技术
·
防伪技术
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DOI
高影响因子
ANALYST
·
2013
·Vol. 138
·期 6
·1851-1857
·
IF 3.969
Huanshun Yin,Zhenning Xu,Yunlei Zhou,Mo Wang,Shiyun Ai
A label-free electrochemical immunosensor for ultra-sensitive detection of indole-3-acetic acid (IAA), a very important phytohormone, has been developed in this work. The detection strategy was mainly based on 4-aminophenylboronic acid, magnetic nanoparticles functionalized with horseradish peroxidase-conjugated goat anti-rat immunoglobulin G (HRP-IgG-Fe3O4) and rat monoclonal antibody against IAA-modified gold nanoparticles (anti-IAA-AuNPs). HRP-IgG-AuNPs was covalently assembled on the electrode surface through the specific chemical reaction between boronic acid and the vicinal diol in HRP-IgG. Then, anti-IAA-AuNPs was further assembled on the electrode via the interaction between IgG and antibody. Through the dual amplification of HRP-IgG-Fe3O4 and anti-IAA-AuNPs, the trapping capacity of the immunosensor for IAA was significantly enhanced based on the promotion of the immunoreaction between antibody and antigen, which resulted in a large decrease of the electrochemical response of the redox probe, Fe(CN)63−, and an increase in sensitivity. The developed electrochemical immunosensor exhibited a wide linear range from 0.02 to 500 ng mL−1 with a low detection limit of 0.018 ng mL−1 (S/N = 3). Moreover, the proposed immunosensor showed acceptable selectivity, reproducibility, accuracy and stability. The IAA extracted from various seeds was successfully detected using the developed immunosensor. This assay method might provide an alternative strategy for the detection of various phytohormones.
研究领域:
分析化学
·
植物科学
·
纳米技术
·
电化学
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DOI
PubMed
高影响因子
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