FOOD CHEMISTRY
·
2020
·
IF 6.306
Dingmin Zhang,Xiaoyun Jiang,Liubang Xiao,Yongling Lu,Shengmin Sang,Lishuang Lv,Wenjiang Dong
Acrolein (ACR) is an unsaturated aldehyde with high activity and toxicity and is produced in vivo and in food. This study investigated the impact of B-ring structure on the trapping of ACR by flavonols and the trapping mechanism and efficacy of ACR by myricetin. Galangin, kaempferol, quercetin, and myricetin, which possess the same A- and C-ring but different numbers of –OH groups on the B-ring, were selected for this study. Our results suggested that increasing the number of –OH groups on the B-ring can enhance the ACR trapping efficacy of flavonol and myrectin was identified as the most active flavonol. The adducts of myricetin with ACR under different ratios and incubation times were analyzed using LC-MS/MS. We also purified and identified the major mono- and di-ACR-myricetin adducts. Furthermore, myricetin could dose-dependently inhibit the formation of ACR in cookies through the formation of mono- and di-ACR adducts.
研究领域:
食品科学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
POLYMER
·
2021
·
IF 4.43
Peng Wei,Hejuan Lou,Jinfei Yan,Longlong Li,Yifeng Zhang,Yumin Xia,Yanping Wang,Yimin Wang
In order to obtain thermotropic liquid crystal polymers (TLCP) with excellent comprehensive performance, naphthalene monomers (amount exceeding 50 mol%) of 6-hydroxy-2-naphthoic acid (HNA) and 2,6-naphthalene dicarboxylic acid (NDA) were used to prepare wholly aromatic TLCP with strong molecular interaction via “one-pot” melt polymerization method in this work. The structure and properties of the copolyesters were fully investigated by experimental measurements and molecular simulation . The simulation results indicated that the naphthalene TLCPs had less chain mobility and stronger molecular interactions, and resulted in a linear rigid chain conformation, endowing the copolyesters with superior properties. As compared with the control copolyester M without naphthalene units, the resulted copolyesters had higher glass transition and melting temperature, higher melt tension, better thermal stability and fiber mechanical property. Overall, the rigidity, molecular interaction and properties of the obtained copolyesters could be efficiently improved after incorporation of the naphthalene units, which is beneficial for its processing and application.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
CARBON
·
2025
·
IF 11.6
Yuting Liu,Heping Niu,Zhihong Wang,Jialin Liang,Liang Ren,Jisheng Zhou
Hard carbons (HCs) derived from pitch show promise as low-cost anodes for sodium-ion batteries (SIBs) due to their high carbon yield. However, pitch's complex polyaromatic structure makes its modification and HC microstructure control difficult. This study selects bicyclic naphthalene (Nap), tricyclic phenanthrene (Phe) and tetracyclic pyrene (Pyr) as model precursors to investigate how the aromatic ring number impacts HCs' cross-linking mechanisms, microstructure, and electrochemical performance. HCs based on Nap, Phe and Pyr are prepared via combined molecular and oxidative cross-linking. After molecular cross-linking, polycyclic aromatic resin's layer size and aromaticity grow with precursor ring number, R-Pyr having the largest aromatic layers and strongest π-π interactions. During oxidative cross-linking, these layers enhance –C(O)O group retention and 3D stacking, leading to closed pores with smaller size, larger volume, and thicker graphite microcrystals. Consequently, Pyr-based HCs (Pyr-HC) exhibit superior electrochemical performance, with a reversible capacity of 328.20 mAh g −1 at 0.1 A g −1 . In full-cell tests, the Pyr-HC || NVP reaches 184.8 mAh g −1 at 1 A g −1 and an energy density of 147.2 Wh kg −1 , retaining 74.78 % of its capacity after 200 cycles. This work highlights the importance of precursor structure for HC optimization and screening pitch precursors.
研究领域:
材料科学
·
能源存储
✓ 已验证
产品关联
DOI
高影响因子
Advanced Science
·
2024
·
IF 14.3
Wentong Meng,Sifan Chen,Pu Chen,Feng Gao,Jianguo Lu,Yang Hou,Qinggang He,Xiaoli Zhan,Qinghua Zhang
Positively charged nanofiltration membranes have attracted much attention in the field of lithium extraction from salt lakes due to their excellent ability to separate mono- and multi-valent cations. However, the thicker selective layer and the lower affinity for Li + result in lower separation efficiency of the membranes. Here, PEI-P membranes with highly efficient Li + /Mg 2+ separation performance are prepared by introducing highly lithophilic 4,7,10-Trioxygen-1,13-tridecanediamine (DCA) on the surface of PEI-TMC membranes using a post-modification method. Characterization and experimental results show that the utilization of the DCA-TMC crosslinked structure as a space-confined layer to inhibit the diffusion of the monomer not only increases the positive charge density of the membrane but also reduces its thickness by ≈35% and presents a unique coffee-ring structure, which ensures excellent water permeability and rejection of Mg 2+ . The ion–dipole interaction of the ether chains with Li + facilitates Li + transport and improves the Li + /Mg 2+ selectivity ( S Li,Mg = 23.3). In a three-stage nanofiltration process for treating simulated salt lake water, the PEI-P membrane can reduce the Mg 2+ /Li + ratio of the salt lake by 400-fold and produce Li 2 CO 3 with a purity of more than 99.5%, demonstrating its potential application in lithium extraction from salt lakes.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2023
·
IF 3
Yiqing Xia,Shuai Yan,Rui Shi,Linze Liu,Junlong Zhu,Yuntao Zeng,Chen Gao,Wilfred Emori,Yuping Sheng
With the rapid development of ultra-large-scale integrated circuits and aerospace, the demand for materials with excellent overall performances is on the rise. In this study, we have successfully synthesized novel main-chain benzoxazine precursors ((BPA-AD/dd1) main ) containing both cycloaliphatic and aliphatic structures by employing adamantanediamine and Priamine 1074 for the first time, and their chemical structures and polymerization behaviors were characterized using Fourier transform infrared spectroscopy (FT-IR), NMR spectroscopy ( 1 H-NMR) and differential scanning calorimetry (DSC). The results showed that the exothermic onset of the (BPA-AD/dd1) main shifted to lower temperatures with an increasing molar ratio of Priamine 1074. Furthermore, the thermal properties, dielectric properties, surface hydrophobicity, and tensile properties of P(BPA-AD/dd1) main films were explored via dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), contact angle measuring instrument, an impedance analyzer and universal testing machine. The molar ratio of Priamine 1074 and 1,3-Bis(4-anilino)-adamantane (AD) significantly influenced the thermal properties, dielectric properties, and surface hydrophobicity of P(BPA-AD/dd1) main . P(BPA-AD 0.75) main exhibited a high T g of 296.8°C, excellent dielectric properties ( Dk = 2.58 and Df = 0.0055 @ 10 MHz), and large water contact angle as high as 105.8°, qualifying it as a potential candidate for interlayer materials in ultra-large-scale integrated circuits and resin matrix in high-performance composites.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2024
·
IF 9.4
Pengbo Li,Yuanrong Zhang,Haodi Liu,Yanfen Fang,Shuaitao Li,Xun Hu,Qifeng Chen
The conjugated structure of graphitic polymeric carbon nitrides (GPCNs) has low efficiency in the photocatalytic hydrogen peroxide (H 2 O 2 ) production, due to the electronic properties, band structure, and surface-active-sites. Herein, boron and carbon-ring modified GPCNs were synthesized with via a thermal condensation method, using melamine and phenylboronic acid as raw materials. The introduced boron atom, conjugated to the carbon atom in the heptazine moiety, and the adjacent nitrogen vacancy (V N ) formed a dual-site, which not only modified the electronic properties but also promoted the adsorption and activation of molecular dioxygen; The carbon-ring introduced altered the band structure and electron distribution, which was proved by density functional theory (DFT) calculations. The co-modification promoted the conversion of dioxygen molecule to H 2 O 2 , coupled with oxidation of benzyl alcohol (BA) to benzaldehyde (BAD). The optimal activity was achieved over CN-B 3 (1.87 mmol/(g·h)), which was about 4-fold higher than that of PCN (0.49 mmol/(g·h)). More interestingly, mechanism study revealed that the photocatalytic H 2 O 2 generation was realized via a photon energy transfer route, that is, O 2 molecule firstly was converted to a highly active singlet oxygen ( 1 O 2 ) intermediate, which was reduced by electrons to superoxide anions ( O 2 − ) and coupled with proton to form H 2 O 2 . This method provides a novel strategy to improve photocatalytic H 2 O 2 and high value-added chemical production by regulating the microstructure and electronic structure of GPCNs through heteroatom and moiety co-modification.
研究领域:
材料科学
·
环境科学
·
理论化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2023
·Vol. 34
·期 7
·1-12
·
IF 2.8
Zhang Xinle,Chi Qingguo,Tang Chao,Li Hua,Zhang Changhai,Li Zhonghua,Zhang Tiandong
The rapidly growing third-generation wide-band-gap semiconductor electronic device industry urgently requires high-temperature-resistant packaging materials. However, the epoxy molding compound materials cannot suffer the high-temperature working condition due to the intrinsic molecular chain structure of epoxy materials (EP). In this paper, bisphenol A-type cyanate (BADCy) with triazine ring structure was introduced into EP to improve its heat resistance. The curing reaction as well as the curing mechanism has been clearly revealed for BADCy/EP with different contents of BADCy according to the Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimeter (DSC) results. In the whole copolymer system, the copolymer at higher BADCy concentration (50–60 mol%) achieved the highest crosslink density (12.8 × 10 –3 mol/cm 3 ), thus, showing excellent glass transition temperature (> 200 °C) and thermal decomposition temperature( T 5% > 400 °C). The heat resistance and electrical insulation property of BADCy/EP system have been systematically investigated, and a balance between high heat resistance and good electrical insulation are achieved at 66 mol% BADCy content, where the glass transition temperature reaches 215 °C, which is 73 °C higher than that of the EP system of anhydride copolymer. The volume resistivity of 1.5 × 10 15 Ω·m and dielectric constant of 3.3 is obtained, indicating excellent electrical insulation and dielectric properties of BADCy/EP. This work provides a facile and efficient strategy to improve the overall properties of EP by optimizing the molecular chain structure.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2025
·Vol. 17
·期 8
·1029
·
IF 4.9
Caiyun Liu,Shuzhen Ni,Zhaojiang Wang,Yingjuan Fu,Menghua Qin,Yongchao Zhang
During the conventional biomass fractionation, the degradation and dissolution of lignin and hemicellulose result in a complex extract which remains very challenging for the thorough separation and purification of a wide variety of fractionated products, limiting their further utilization. Herein, we proposed a facile and efficient strategy for fractionating biomass and simultaneously in situ converting of both lignin and hemicellulose into single products using a formic acid–phloroglucinol system. The introduced phloroglucinol could react with lignin fragments and hemicellulose-derived products, and the generated intermediate product from hemicellulose can be further condensed with lignin fragments, finally forming single lignin-based functional biopolymers containing heterocyclic structures. Only small amounts of hemicellulosic derivatives, such as oligosaccharides, monosaccharides, furfural, and 5-HMF, were detected in the extracted solution, indicating a highly directional and effective in situ conversion process of hemicellulose. The constructed specific structures on fabric surfaces by using the chelation between lignin-based functional biopolymers and metal ions achieved the preparation of functional fabrics with stable hydrophobicity. The dynamic contact angle of water droplets on the surface of prepared fabric only decreased from 122° to 116.8° over 30 min. This work strategy provides an ideal route to maximize the utilization of both lignin and hemicellulose without involving complex separation and purification procedures. This strategy is the first demonstration of using the targeted fractionation system to achieve the simultaneous conversion of hemicellulose and lignin into single functional biopolymers directly from lignocellulosic biomass.
研究领域:
化学工程
·
材料科学
·
生物质利用
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DALTON TRANSACTIONS
·
2016
·Vol. 45
·期 16
·7124-7130
·
IF 4.177
Li-Jun Zhang,Yan-Yan Li,Peng-Fei Liu,Ling Chen
New borophosphates Li3Cs2M2B3P6O24 (M = Pb, Sr) have been synthesized by high-temperature solid-state reactions. The single-crystal X-ray diffraction data reveal their non-centrosymmetric cubic space group P213 and lattice parameters of a = 12.7246(3) Å and 12.687(2) Å and V = 2060.31(8) Å3 and 2042.3(4) Å3 for Li3Cs2Pb2B3P6O24 and Li3Cs2Sr2B3P6O24, respectively. They are three-dimensional (3D) [BP2O8]3−∞ anionic frameworks formed by a new double six-membered ring building unit consisting of BO4 and PO4 units joined alternately. Interestingly, such a double six-membered ring is regarded as the structural variation of the 12-membered ring in the known KSrBP2O8, fusing at the BO4 tetrahedron induced by the coexistence of the Li+ and Cs+ cations with their large size difference. The title compounds show weak SHG intensity and exhibit photoluminescence emissions at 410 nm for Li3Cs2Pb2B3P6O24 and 440 nm for Li3Cs2Sr2B3P6O24.
研究领域:
材料科学
·
晶体学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2023
·
IF 3.8
Xiangrong Li,Ruonan Xu,Tianjun Ni
Flavonols are studied extensively because of their interesting biological activities. Galangin, kaempferol, quercetin, and myricetin are structurally related flavonols that differ only in the number of B-ring hydroxyl substituents. In this work, we have carried out a detailed study on the interaction of these structurally related flavonols and γ-globulin/fibrinogen/trypsin/pepsin by using experimental as well as molecular docking approaches. Studies show that the flavonol-protein complex is formed after the interaction of flavonols with the four proteins, which has moderate quenching and binding ability. The effects of the number and position of the hydroxyl groups in flavonols B-ring on the quenching constant, binding constant, number of binding sites, thermodynamic parameters as well as the changes of the secondary structure of proteins are elucidated. The interaction between flavonols and γ-globulin/fibrinogen/trypsin/pepsin is a spontaneous exothermic process driven by enthalpy and entropy, and the main force types are hydrophobic and hydrogen bonds. For some systems, electrostatic forces are also involved. The interaction of flavonols with the four proteins results in loosening and unfolding of backbone of proteins. Moreover, galangin and quercetin also reduce the hydrophobicity of the tryptophan (Trp) microenvironment. The secondary structure of γ-globulin/fibrinogen/trypsin is affected by the number of hydroxyl groups on the B-ring. Except that myricetin does not bind to the catalytic active center of pepsin and seems to have no inhibitory effect on the activity of pepsin, for other flavonol-fibrinogen/trypsin/pepsin systems, flavonols are bound to the active center of the three proteins, and have certain influence on the activity of them.
研究领域:
生物化学
·
药理学
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR RAPID COMMUNICATIONS
·
2023
·Vol. 45
·期 3
·2300510
·
IF 4.6
Kangkang Tao,Gaohui Sun,Shuai Zhang,Jun Wang,Rongrong Chen,Shihui Han
Polyimide (PI) film with hydrophilic greatly limits their application in the field of microelectronic device packaging. A novel hydrophobic PI film with sag structure and improved mechanical properties is prepared relying on the reaction between anhydride-terminated isocyanate-based polyimide (PIY) containing a seven-membered ring structure and the amino-terminated polyamide acid (PAA) via multi-hybrid strategy, this work named it as hybrid PI film and marked it as PI-PIY-X. PI-PIY-30 showed excellent hydrophobic properties, and the water contact angle could reach to 102°, which is 20% and 55% higher than simply PI film and PIY film, respectively. The water absorption is only 1.02%, with a decrease of 49% and 53% compared with PI and PIY. Due to that the degradation of seven-membered ring and generation of carbon dioxide led to the formation of sag structure, the size of sag structures is ≈16.84 and 534.55 nm for in-plane and out-plane direction, which are observed on surface of PI-PIY-30. Meanwhile, PI-PIY-30 possessed improved mechanical properties, and the tensile strength is 109.08 MPa, with 5% and more than 56% higher than that of pure PI and PIY film, showing greatly application prospects in the field of integrated circuit.
研究领域:
材料科学
·
微电子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers of Chemical Science and Engineering
·
2020
·Vol. 15
·期 2
·351-362
·
IF 3.552
Wei Xiuzhen,Xu Xufeng,Chen Yi,Zhang Qian,Liu Lu,Yang Ruiyuan,Chen Jinyuan,Lv Bosheng
Polyamide (PA) hollow fibre composite nanofiltration (NF) membranes with a coffee-ring structure and beneficial properties were prepared by adding graphene oxide (GO) into the interfacial polymerization process. The presentation of the coffee-ring structure was attributed to the heterogeneous, finely dispersed multiphase reaction system and the “coffee-stain” effect of the GO solution. When the piperazine concentration was 0.4 wt-%, the trimesoyl chloride concentration was 0.3 wt-%, and the GO concentration was 0.025 wt-%, the prepared NF membranes showed the best separation properties. The permeate flux was 76 L·m −2 ·h −1 , and the rejection rate for MgSO 4 was 98.6% at 0.4 MPa. Scanning electron microscopy, atomic force microscopy, and attenuated total reflectance-Fourier transform infrared spectroscopy were used to characterize the chemical structure and morphology of the PA/GO NF membrane. The results showed that GO was successfully entrapped into the PA functional layer. Under neutral operating conditions, the PA/GO membrane showed typical negatively charged NF membrane separation characteristics, and the rejection rate decreased in the order of Na 2 SO 4 > MgSO 4 > MgCl 2 > NaCl. The PA/GO NF membrane showed better antifouling performance than the PA membrane.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）