MATERIALS SCIENCE FORUM
·
2014
·
IF 0
Zhi Jia Luo,Hong Zhang Geng,Song Ting Zhang,Bao Tan Du,Xing Zhang,Jing Wang,Zhan Guo Lu,Su Jun Ma,Jin Qiu Zhang,Hai Jie Yang,Jie Wang
Graphene oxide (GO) is typically synthesized by graphite powder under strong oxidizing reaction, possessing with the same set of functional groups: epoxy and hydroxyl in basal plane and carboxyl and hydroxyl groups existence on the flake edges which endow GO with amphipathy. GO and its functionalized derivatives have been successfully tested in many domains, such as polymer composites, biosensors, drug delivery systems, etc. In this paper, GO was prepared by a modified Hummers method employing improved process (preparation and separation), aiming at industrialization with the lowest cost. Moreover, some novel functional groups with different properties were controlled chemically grafted onto GO to modify the wettability and reaction activity with other materials. The hydrophobicity and the thermal property of graphene oxide were enhanced by chemical functionalization.
研究领域:
材料科学
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化学工程
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DOI
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2017
·Vol. 25
·期 10
·1435-1441
·
IF 1.174
Zhirong Chen,Weitao Yang,Hong Yin,Shenfeng Yuan
The uncatalyzed reaction of p -tolyl isocyanate ( p -TI) with water in N , N -dimethylformamide (DMF) was investigated by high performance liquid chromatography (HPLC). The reactions were carried out at different temperatures from 293 K to 323 K, using various molar ratios of water to p -TI. DMF, as a special amide , was proved to be an efficient catalyst for water–isocyanate reaction. Under the reaction conditions in this study, substituted urea was the only final product observed. An appreciable amount of intermediate p -toluidine was detected. Concentrations of the isocyanate group as well as the amine and urea were determined as a function of time. New kinetic equations were deduced for each of the substance on the basis of a multistep mechanism, instead of a simple second order reaction as usual. Kinetic constants were calculated using the software MATLAB . Furthermore, the effects of temperature and concentrations of reactants on the reaction rate and amine content were discussed. The activation energy of each step was also determined.
研究领域:
物理化学
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有机化学
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反应动力学
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高分子化学
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催化化学
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分析化学
✓ 已验证
DOI
高影响因子
Reaction Chemistry & Engineering
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2025
·
IF 3.1
Xiangyu Wen,Qiusheng Yang,Ming Li,Xiaoshu Ding,Peng Zhai,Yao Lu,Xinqiang Zhao,Yanji Wang,Dongsheng Zhang
Amino-methyl-N-phenylcarbamate (TMC) is an important organic intermediate. In this study, a new two-step route, i.e., methoxycarbonylation and direct amination reaction, was designed for synthesis of TMC. During this process, p-Toluidine first reacted with dimethyl carbonate to form metholylcarbamate (MTCM), and then MTCM further converted to TMC via direct amination reaction. It was found that in methoxycarbonylation process, Zn(OAc)2 catalyst was a better choice and p-Toluidine was almost completely converted into MTCM, corresponding to 99% p-Toluidine conversion and 95.4% MTCM yield. As for direct amination reaction, Fe-V/ZSM-5 bimetallic catalyst was selected and high yield of total TMC was obtained at 69.6%. The catalyst characterization results showed that the synthesized bimetallic catalysts retained the structural features of ZSM-5, while the abundance of metal ions on the surface promoted the reaction
研究领域:
有机化学
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催化化学
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药物化学
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化学工程
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材料科学
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工业化学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2021
·
IF 7.46
Yawen Rong,Md Mehedi Hassan,Qin Ouyang,Li Wang,Tianhui Jiao,Quansheng Chen
The current work puts forward a turn-off ratiometric upconversion fluorescence nanosensor for the quantification of furfural (FUR). Upconversion nanoparticles (UCNPs) containing Y 3+ , Yb 3+ , and Er 3+ were synthesized; mesoporous SiO 2 and amino groups were subsequently conjugated and functioned as the signal component. The p-toluidine molecule played the role of recognition molecules, which coupled with UCNPs to form a unique detection system. An absorption peak appeared when the FUR was combined with p-toluidine resulted in an obvious quenching of upconversion emission at 539 nm via inner filter effects (IFE), while the fluorescence peak at 653 nm maintained constant. Therefore, the FUR concentration was quantified by the record of fluorescence ratio I 539 / I 653 . Under optimal conditions, the proposed UCNPs-p-toluidine coupled nanosystem achieved the ratiometric fluorescence sensing toward FUR in the linear range of 0.01–100 μg/mL with a detection limit as low as 0.003 μg/mL. The accuracy of the sensor was validated by the HPLC method with preferable accuracy. Finally, the overall nanosystem showed excellent application potential in adulterated foodstuff (e.g., cookie, honey, fruit wine, milk tea, and potato chips).
研究领域:
分析化学
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食品科学
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纳米技术
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光谱学
✓ 已验证
产品关联
DOI
高影响因子
Science Advances
·
2026
·Vol. 12
·期 8
·
IF 13.9
Weijian Sun,Kaicheng Yang,Yifan Zhao,Liping Sun,Qingchi Xu,Jian Weng,Jun Xu
Traditional petroleum distillation faces high energy demands, necessitating innovative alternatives like membrane separation. This study presents a breakthrough in dual-range and precise pore size modulation of metal-organic frameworks (MOFs) through a ligand functionalization strategy. By tailoring steric configurations and spatial orientations of light-responsive azobenzene groups, we achieved broad-range pore tuning (0.41 to 0.68 nanometers) via functional group length variation, coupled with subnanometer precision through reversible trans-to-cis photoisomerization. Four representative branched alkanes were selected to validate the MOF’s high selectivity. Results showed its capacity to generate a constant carbon-atom-count–dependent permeation gradient, realizing a four-step sequential separation that increased C 6 H 14 purity from 25 to 92.2%. This synergistic approach uniquely combines large-scale pore adjustment with dynamic fine-tuning, decoupling separation efficiency from energy-intensive processes. The membranes’ structural stability and reversible light responsiveness further highlight their potential for sustainable hydrocarbon processing. By integrating molecular design with stimuli-responsive control, this work advances MOF-based membranes as a transformative solution for energy-efficient petroleum fractionation and precise molecular sieving.
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产品关联
DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2026
·
IF 19.9
Xue Zhang,Xu Tong,Zhiqi Zhou,Changhai Zhang,Tiandong Zhang,Wenju Wu,Chao Wang,Shuya Fu,Chao Yin,Qingguo Chi
A major challenge in developing high-temperature polymer dielectrics is the difficulty in simultaneously achieving a high dielectric constant, a wide bandgap ( E g ), and a high glass transition temperature ( T g ). To address this challenge, this study designed and synthesized a series of polynorbornene imides with methyl groups at the para position and substituents of varying steric hindrance and electronegativity (F, Cl, Br, CF 3 ) at the meta position from the perspective of molecular side-chain configuration. Molecular dynamics simulations and density functional theory calculations reveal that the steric hindrance of meta -substituents can regulate the side-chain configuration ratio in polymers. Specifically, as the substituent steric hindrance increases, the proportion of the isotactic configuration decreases while the syndiotactic configuration increases. The isotactic configuration enhances the polarization performance by strengthening the local dipole moment and the syndiotactic configuration improves insulation by increasing free volume and suppressing charge migration. The meta -chloro-substituted PNIM-Cl achieves a balance between isotactic and syndiotactic configurations through its moderate steric hindrance and electronegativity and results a high dielectric constant (4.04), a wide E g (4.27 eV), and an elevated T g (231.8°C). Consequently, the PNIM dielectric achieves remarkable discharged energy densities of 11.4 J cm − 3 at 150°C and 6.4 J cm − 3 at 200°C.
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产品关联
DOI
高影响因子
ACS Applied Polymer Materials
·
2026
·
IF 5.2
Linzhu Xu,Qingyun Zhao,Birong Zeng,Jie Song,Ziyun Chen,Yilin Su,Zhenlong Luo,Yiting Xu,Conghui Yuan,Lizong Dai
Developing intelligent polyurethane elastomers with balanced high mechanical strength and rapid self-healing capability remains a critical challenge in advanced functional materials. Herein, we designed a kind of polyurethane elastomer of PU-A1D2 by incorporating the azobenzene compound of 3-(4-(p-tolyldiazenyl)phenoxy)propane-1,2-diol (Azo-2) and dimethylglyoxime into the polyurethane matrix as components of the chain extender, where the dual functional groups synergistically contribute to self-healing performance. Dynamic oxime-urethane bonds construct a covalent adaptable network, enabling excellent self-healing in PU-A1D2 via reversible dissociation-association, while light-responsive Azo-2 units undergo photoisomerization, inducing topology transition and reversible soft–hard switching. The resultant PU-A1D2 exhibited a tensile strength of 13 MPa, toughness of 50 MJ m–3, and 95% self-healing efficiency after heat treatment at 80 °C for 12 h, achieving a favorable balance between mechanical robustness and self-healing efficiency. Moreover, PU-A1D2 achieved complete scratch self-healing within 2 h under the synergistic effect of ultraviolet (UV) irradiation and 90 °C. In addition, the 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide (EMIM·TFSI)-doped PU-A1D2-ET achieved almost 100% self-healing efficiency within merely 10 min under room-temperature UV irradiation. This work clarifies the regulatory mechanism of azobenzene on polyurethane self-healing and provides a promising design strategy for fabricating high-performance polymer elastomers integrated with outstanding mechanical properties and rapid light-controlled self-healing, which holds great potential in flexible electronics and smart wearable devices.
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产品关联
DOI
高影响因子
Polymer Chemistry
·
2025
·
IF 3.9
Lin Xie,Kan Zhang
In this study, we successfully designed and synthesized a series of bio-based benzoxazine resins using p-toluidine/aniline/3-ethynylaniline, paraformaldehyde and natural renewable isoliquiritigenin through a Mannich reaction. Nuclear magnetic resonance (NMR), Fourier transform infrared (FT-IR) spectroscopy, and high-resolution mass spectrometry (HR-MS) were employed to precisely analyze their chemical structures. Besides, the curing behavior of each benzoxazine resin was explored by differential scanning calorimetry (DSC) and in situ FT-IR, which revealed that the synergistic effects from catalytic hydroxyl groups and electron-withdrawing alkynyl groups and carbon–carbon double bonds significantly reduce the curing peak temperatures. Moreover, dynamic mechanical analysis (DMA) and thermogravimetric analysis (TGA) data indicated that the alkynyl groups and carbon–carbon double bonds provide extra cross-linking sites during polymerization, which greatly enhances the thermal stability with a Td10 of up to 432 °C, Tg of 389 °C, and Yc of 71.2% at 800 °C. Owing to such outstanding properties, the newly obtained bio-based resins synthesized from isoliquiritigenin are highly suitable for high performance application fields.
研究领域:
材料科学
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化学工程
·
高分子化学
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产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2025
·
IF 11.3
Wen Qin,Chengyuan Zheng,Haoming Qin,Yang Song,Yang Zhou,Jin Jiang,Jun Ma
Permanganate/electron shuttle systems for the enhanced transformation of anilines were evaluated. The presence of electron shuttles (2,2’-azino-bis(3-ethylbenzothiazoline)-6-sulfonate (ABTS), 1-hydroxybenzotriazole (HBT) and catechol (CAT) accelerated the oxidative transformation of aniline by Mn(VII). In the Mn(VII)/ABTS process, ABTS •+ was partially consumed through fragmentation or polymerization with aniline, while the second-order rate constants ( k app 2 , M −1 s −1 ) of the interaction of ABTS •+ with aniline rose from 86.57 to 140.04 M −1 s −1 with increase in pH from 5 to 8. In the Mn(VII)/HBT system, aniline removal was markedly enhanced under acidic conditions due to the formation of polymerized products via radical cations (HBT • ). Furthermore, the oxidative transformation of aniline (82.5 %) by Mn(VII)/CAT was significantly higher than that by Mn(VII) (65.2 %) because of Michael addition reaction of aniline and ortho-benzoquinone (o-BQ). Moreover, the formation of Mn(III) was confirmed by the overall oxidation state (3.13) and the X-ray Photoelectron Spectroscopy (XPS) spectra of the Mn products in the CAT/Mn(VII) process, revealing a synergistic mechanism between o-BQ and Mn(III) for enhanced aniline degradation.
研究领域:
环境科学
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化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2024
·
IF 8.2
Yizhou Feng,Daohui Lin,Kun Yang,Wenhao Wu
Knowledge of antibiotic desorption from high-temperature biochar is essential for assessing their environmental risks, and for the successful application of biochar to remove antibiotics. In previous studies, irreversible pore deformation, formation of charge-assisted hydrogen bonds or amide bonds were individually proposed to explain the desorption hysteresis of antibiotics on biochars, leading to a debate on hysteresis mechanism. In this study, desorption of sulfamethoxazole (SMX), ciprofloxacin (CFX) and tetracycline (TET) on a wood chip biochar produced at 700 °C (WBC700) and its oxidized product (O-WBC700) was investigated to explore the underlying hysteresis mechanism. Significant desorption hysteresis was observed for SMX, CFX and TET on WBC700 and O-WBC700. Hysteresis index (HI) of each antibiotic was higher on O-WBC700 with more oxygen-containing groups than WBC700, and was higher at lower equilibrium concentration. HI of antibiotics on WBC700 (or O-WBC700) increased in the order of SMX < CFX < TET. The calculated adsorption enthalpy of each antibiotic on WBC700 was positive, indicating an endothermic process. These phenomena together with FTIR, XPS spectra confirmed that the desorption hysteresis mechanism of antibiotics on high-temperature biochar is the formation of amide bonds by amidation reaction, but not the pore deformation or the hydrogen bond. Moreover, antibiotic can form amide bonds with WBC700 only if the amine group with p K a > 4.0, and the HI values were positively correlated with their p K a values. Amine group of antibiotics with higher p K a value show more nucleophilicity and could form stronger amide bonds with carboxyl group of biochar. The obtained results could help to solve the debate on desorption hysteresis mechanism of antibiotics on high-temperature biochars, and provide a new insight into the role of amine groups and amidation reaction on the hysteresis.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2024
·
IF 8.1
Miao Cao,Yulang Qiu,Man Yang,Yanyan Zhang,Qiange Li,Shishen Zhang,Peng Li,Qi Sui
Construction of a proper electron donor-acceptor (D-A) microenvironment through introducing a suitable chemical moiety is an effective strategy to facilitate photogenerated charge transfer in a cascade step actively, which can boost the corresponding photocatalytic performance significantly. Herein, a series of naphthalenediimide ( NDI y ), possessing unique electron-deficient aromatic imides, were introduced to prepare D-A structured g -C 3 N 4 ( CN ) derivative hybrid photocatalysts for photocatalytic hydrogen evolution (PHE) from water splitting. Remarkably, the modification with NDI y all significantly improved the PHE performance, in which 1%NDI NH2 @CN exhibits the best photocatalytic activity (14.57 mmolꞏg −1 ꞏh −1 ), exceeding 5.6 times over the unmodified pure CN under the same conditions. The enhanced PHE activity is highly associated with the interfacial D-A interactions between NDI y and CN , which also lays the foundation for the further rational design of analogs toward various types of photocatalytic reactions.
研究领域:
材料科学
·
环境科学
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产品关联
DOI
高影响因子
ACS Omega
·
2024
·
IF 3.7
Shiqiang Hou,Ning Lin,Yi Wang
Red-emitting fluorescent carbon dots (CDs) have garnered significant attention due to their wide-ranging applications in biological fields. However, challenges such as complex precursors, labor-intensive preparation processes, and low quantum yields have hindered their broader utilization. In this study, we developed a simple and efficient solvothermal method to synthesize fluorescent CDs with tunable emission wavelengths using aniline derivatives as precursors. The emission wavelengths of the synthesized CDs were influenced by the functional groups at the para-position of the aniline derivatives with stronger electron-donating effects leading to a red shift in emissions. Notably, bright red-emitting CDs with a quantum yield of 19.42% and excellent photobleaching resistance were obtained by using p-phenylenediamine as the sole precursor. These CDs exhibited sensitivity to Fe3+ ions, demonstrating a strong linear detection range (R2 = 0.999) from 0 to 50 μM. Additionally, the CDs were uniform in size (2–5 nm), emitted stable red fluorescence in pH conditions ranging from 4 to 10, and were successfully internalized by glioma cells, enabling precise fluorescence imaging of gliomas both in vitro and in vivo.
研究领域:
生物医学工程
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材料科学
·
肿瘤学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）