TALANTA
·
2015
·
IF 3.545
Hong-Wei Zhu,Wen-Xia Dai,Xiao-Dong Yu,Jing-Juan Xu,Hong-Yuan Chen
In this work, poly-thymine stabilized copper nanoclusters have been used as a fluorescence probe for melamine sensing for the first time. Melamine can bind to thymine through hydrogen bond , which could dramatically enhance the fluorescence intensity of poly-thymine stabilized copper nanoclusters. The enhancement factors ( I − I 0 )/ I 0 increase linearly with the lgC melamine over the melamine concentration range of 0.1 µM to 6 µM. The detection limit of melamine is 95 nM, which is 200 times lower than the US Food and Drug Administration estimate melamine safety limit 20 µM. Melamine in milk was detected with good recovery, which suggested that this novel fluorescence probe has great potential in practical application.
研究领域:
分析化学
·
纳米技术
·
食品安全
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DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2017
·
IF 3.387
Zhiwen Lei,Guangzhao Zhang,Yonghong Deng,Chaoyang Wang
Inspired by the development of smart oil/water separation materials, a pH responsive melamine sponge has been obtained by grafting poly (4-vinylpyridine) on the skeleton surface through atom transfer radical polymerization. Through scanning electron microscopy and x-ray photoelectron spectroscopy, the successful grafting of poly (4-vinylprridine) onto the melamine sponge has been confirmed. When contacting with different pH water droplets in air, the as-prepared product shows excellent switchable wettability between super-hydrophilicity (0°) and highly hydrophobicity (135°). Meanwhile, this responsive sponge also exhibits super-hydrophilic/oleophobic property underwater at pH = 1.0, and highly hydrophobic/super-oleophilic property in neutral solution at pH = 7.0. Furthermore, the excellent responsiveness is remained after five cycle water contact angle tests between two different pH stages at pH 1.0 and 7.0. The modified melamine sponges could not only absorb the oil from the oily water at pH = 7.0, but also quickly release the absorbed oil underwater at pH = 1.0 without leaving any residues and hurting the environment nearly, showing a good potential in controlled oil/water separation and oil recovery.
研究领域:
材料科学
·
环境工程
·
高分子化学
·
智能响应材料
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 140
·期 9
·e53546
·
IF 3.057
Wei Lu,Zhipeng Zeng,Zhenglong He,Yuntao Liang,Yong Sun,Shuanglin Song,Lili Wang,Ruling Liu
A highly dispersed melamine/red phosphorus (MA/RP) composite flame retardant was prepared by means of simple mechanical grinding. After co-thermal pretreatment with polyether polyol (PPG-2000) at 135°C, organic–inorganic hybrid foams (MA/RP/HF) containing MA/RP flame retardant were prepared by the one-step method using main raw materials such as polyisocyanate and sodium silicate. When 0.5 wt% MA/RP with the mass ratio of 1:5 is added, MA can realize the uniform dispersion of RP in the substrate and enhance its flame retardancy, and the obtained MA/RP/HF presents uniform and closed pores and excellent basic properties. The TG results reveal that MA/RP/HF shows good thermal stability and the corresponding char residual rate reaches 37.9% at 800°C. The flame retardant test results prove that MA/RP/HF is capable of passing the V-0 grade, with the LOI value being 26.8%. According to the cone calorimeter analysis, its peak heat release rate and total heat release decrease by 30.1% and 51.7% compared with those of rigid polyurethane-based foam and by 40.1% and 30.0% compared with those of pure HF, respectively. Finally, the synergistic flame retardancy mechanism of MA and RP on polyurethane-based foam was discussed.
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DOI
高影响因子
ACS Applied Electronic Materials
·
2023
·
IF 4.7
Tingting Yu,Yebo Tao,Yali Wu,Dongguang Zhang,Jiayi Yang,Xingjun Liu
Three-dimensional graphene foam (GF)-based flexible piezoresistive sensors have the advantages of high conductivity, large deformable range and light weight, which has been utilized in human health measurement, electronic skin, and wearable devices. However, the encapsulation and electrode connections of such sensors reduce breathability, resulting in discomfort and even skin irritation. In this study, a self-encapsulated breathable GF (SEB–rGO–MF) and an SEB–rGO–MF-based piezoresistive sensor (SEB–rGO–MF–PS) are proposed. The SEB–rGO–MF–PS consists of a SEB–rGO–MF and two electrodes, ensuring encapsulation and electrical connection without compromising breathability and stability. We performed material characterization and breathability tests of the SEB–rGO–MF and investigated the sensing mechanism of the SEB–rGO–MF–PS. The SEB–rGO–MF–PS exhibits a sensitivity of 0.108 Pa–1, a measurement range of 0.013–15 kPa, rapid response/recovery times (83 and 166 ms), and excellent stability (2000 cycles at 15 kPa). In addition, this study demonstrates the application of the SEB–rGO–MF–PS for human motion monitoring.
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DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2022
·
IF 5.304
Xiang Yuan,Huiling Zhang,Xiang Yuan,Guojiang Mao,Lin Wei
In this work, we demonstrate a simple and label-free single particle detection (SPD) method for the quantification of melamine (Mel) based MnO 2 -modified gold nanoparticles (Au@MnO 2 NPs). Without Mel, MnO 2 shell of Au@MnO 2 NPs are able to be directly decomposed by gallic acid. In the existence of Mel, the decomposition process is restrained due to the strong hydrogen bonding between Mel and gallic acid. The selective etching of MnO 2 shell on AuNPs surface results in evident color change from single Au@MnO 2 NPs. Through quantitatively enumerating the number of color coded particles, trace amounts of Mel can be accurately detected. A linear range from 0.02 to 1 μM (R 2 = 0.98) and a limit of detection of 16.7 nM are acquired. In milk sample, satisfactory recovery was acquired. Therefore, the SPD method is expected to be used for the detection of various chemical contaminants in food.
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DOI
高影响因子
Nanomaterials
·
2022
·Vol. 12
·期 14
·2488
·
IF 5.719
Hanmo Si,Qingwang Liu,Zhenzhong Fan,Biao Wang,Qilei Tong,Mengqi Lin
The problem of offshore oil leakage has wreaked havoc on the environment and people’s health. A simple and environmentally friendly impregnation method combined with marine mussel bionics was used to address this issue. Using the viscosity of polydopamine (PDA), nano- Fe3O4and WS2adhered to the framework of the melamine sponge (MS), and then the magnetic sponge was modified with n-octadecanethiol (OTD), and finally the superhydrophobic magnetic melamine sponge (mMS) was prepared. The modified sponge has superhydrophobicity (WCA, 156.8° ± 1.18°), high adsorbability (40~100 g°g−1), recyclability (oil adsorbability remains essentially unchanged after 25 cycles), efficient oil–water separation performance (>98%), and can quickly separate oil on the water’s surface and underwater. Furthermore, the modified sponge exhibits excellent stability and durability under harsh operating conditions such as strong sunlight, strong acid, strong alkali, and high salt, and can control the direction of the sponge’s movement by loading a magnetic field. To summarize, mMS has many potential applications as a new magnetic adsorption material for dealing with complex offshore oil spill events.Keywords:superyhydrophobicity;melamine sponge;polydopamine;nano-particles;oil–water separation
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产品关联
DOI
PubMed
高影响因子
Nanomaterials
·
2022
·Vol. 12
·期 7
·1202
·
IF 5.719
Zhenming Wang,Jianxun Liu,Jiawei Wang,Zongjun Ma,Delai Kong,Shouzhen Jiang,Dan Luo,Yan Jun Liu
Surface-enhanced Raman spectroscopy (SERS) has long been an ultrasensitive technique for trace molecule detection. However, the development of a sensitive, stable, and reproducible SERS substrate is still a challenge for practical applications. Here, we demonstrate a cost-effective, centimeter-sized, and highly reproducible SERS substrate using the nanosphere lithography technique. It consists of a hexagonally packed Ag metasurface on a SiO2/Au/Si substrate. A seconds-lasting etching process of a self-assembled nanosphere mask manipulates the geometry of the deposited Ag metasurface on the SiO2/Au/Si substrate, which attains the wavelength matching between the optical absorbance of the Ag/SiO2/Au/Si substrate and the excitation laser wavelength as well as the enhancement of Raman signals. By spin-coating a thin layer of graphene oxide on the substrate, a SERS performance with 1.1 × 105analytical enhancement factor and a limit of detection of 10−9M for melamine is achieved. Experimental results reveal that our proposed strategy could provide a promising platform for SERS-based rapid trace detection in food safety control and environmental monitoring.Keywords:SERS;self-assembly;metasurface;surface plasmon;hot spot;sensitivity
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DOI
PubMed
高影响因子
ANALYTICAL SCIENCES
·
2015
·Vol. 31
·期 2
·113-118
·
IF 1.394
Guoyan LIU,Huipeng REN,Yuyu GUAN,Ronghua DAI,Chunyan CHAI
A fast and simple mercury detection kit was developed based on melamine-functionalized gold nanoparticles (GNPs). The detection kit contained reagent 1 (GNPs), reagent 2 (melanine), a reaction cuvette with four separated cells, a colorimetric card and a plastic pipette. The GNPs were prepared by a citrate reduction of HAuCl4. A proper amount of melamine was applied to functionalize the GNPs. The complex reaction took place in the present of Hg2+ in the test samples, leading to the combination of Hg2+ with the C=N group of melamine located on the surface of the GNPs. This reaction resulted in damage to the stability of colloid gold, and the aggregation of GNPs occurred. Different color changes (from claret-red to lilac, purple and plum) were displayed with different concentrations of Hg2+ in the test samples. It was very easy and convenient to determine the amount of mercury ion by the naked eye. The advantages of this methodology are listed as follows: a short detecting time (within 10 min), a high specificity (no significant interference was indicated upon adding a certain amount of Cu2+, Pb2+, Zn2+, Mg2+, Cd2+ and Fe2+), high sensitivity with a detection limit of 0.01 mg L−1 , easy operation and practical on-site use.
研究领域:
环境科学
·
纳米生物学
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DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2016
·Vol. 40
·期 10
·8459-8464
·
IF 3.277
Qianqian Du,Fei Qu,Beibei Mao,Shuyun Zhu,Jinmao You
An efficient sensor was developed for highly sensitive and selective determination of melamine based on Ag nanoclusters (Ag NCs) capped by hyperbranched polyethyleneimine (PEI) molecules with different molecular weights. The fluorescence of the Ag NCs could be quenched by Hg2+ and recovered by melamine. The molecular weights of PEI had an appreciable effect on the sensitivity, and Ag NCs capped by PEI with a molecular weight of 600 were more sensitive; the linear range of melamine was from 0.1 to 30 μM with a detection limit 30 nM. Moreover, this Ag NCs–Hg2+ system displayed excellent selectivity over common interferences such as metal ions, amino acids, sugars and nitrogen-containing organic molecules. Benefiting from the high selectivity, good recoveries ranging from 96% to 101% were obtained in food samples, including milk, infant formula, and dog food. More importantly, Ag NC-doped agarose hydrogels were fabricated easily to construct a visual device for the detection of melamine in food samples.
研究领域:
分析化学
·
食品安全
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产品关联
DOI
高影响因子
Advanced Materials Interfaces
·
2022
·Vol. 9
·期 10
·2102092
·
IF 6.389
Junjun Ma,Yangchun Xie,Tao Yang,Xiaohua He
Innovative 3D materials with the switchable wetting surface attract significant attention due to their application in oil/water separation. Herein, a fast pH-responsive and highly effective melamine foam (MF) grafted with poly (2-dimethylaminoethyl methacrylate) is prepared by surface-initiated chain transfer radical polymerization. The as-prepared MF displays superhydrophilic and superoleophobic surface in strong acid solution while it becomes superhydrophobic in neutral or basic solution. Therefore, it can be rapid to selectively absorb different types of oils from the oil–water mixture with a great absorption capacity of 54–117 g g −1 and automatically desorb oil in less than 60 s with a desorption efficiency of 99% (dichloromethane) in acid solution. Moreover, the as-prepared MF possesses excellent recyclability, and the absorption capacity and the desorption efficiency are almost unchanged after 15 cycles. The pH-sensitive MF with switchable wetting surfaces has great potential for the oily water separation.
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 138
·期 47
·51411
·
IF 3.125
Xing-Ya Liu,Rui-Yang Xie,Tao Chen,Lei He,Ting Wang,Wang Liao,Zhi-Guo Liu,Ming-Jun Chen
Due to the condensation reaction of hydroxylated melamine molecules is possible to take place in the whole pH range, especially in acidic water medium or at high temperature, losing its water solubility. In this work, freeze drying perfectly removes water at pretty low temperature, avoiding condensation reaction of hydroxylated melamine. Therefore, a hydroxylated melamine in solid form (MOH-S) was prepared. It can be not only dissolved in water after storing for 180 days but also well dispersed in waterborne polyurethane emulsion. The addition of hydroxylated melamine significantly improves the tensile strength of polyurethane films by 170%. After soaking the films in water for 24 h, the tensile strength of WPU/30%MOH-S film lost only 6%, but 34% loss for the neat. Fourier transform infrared spectroscopy peak fitting demonstrates that the H-bonding degree of N─H in WPU/30%MOH-S film is 20.72 that is much higher than 3.33 in neat WPU. This indicates that H-bonding cross-linked structure is formed between polyurethane chains and hydroxylated melamine molecules. This work provides an effective strategy for preparing stable hydroxylated melamine and enhancing the strength of polyurethane film.
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高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Lizhi Wang,Jiangfei Guo,Xiyuan Xiang,Yafei Sang,Jianhan Huang
Functionalized porous organic polymers (POPs) with high Brunauer-Emmett-Teller (BET) surface area ( S BET ) and unique porosity is promising while its facile synthesis remains a challenge. Herein, a novel synthesis strategy based on Schiff-base chemistry was developed and melamine was embedded as a rigid external cross-linker to construct a kind of novel functionalized POPs. The resulting melamine-supported polymers showed high S BET (645 m 2 /g) and total pore volume ( V total , 0.84 cm 3 /g) with unique hierarchical porosity, indicative of its outstanding CO 2 capture and Hg 2+ removal. Noticeably, the as-prepared sample TPE-TMC-2MA exhibited high CO 2 uptake of 153 mg/g and its ultramicropore volume ( V ultra , 0.16 cm 3 /g) played a positive role. In particular, the maximum capacity of Hg 2+ reached 392 mg/g, much higher than some other materials reported in the literature.
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DOI
高影响因子
危险品化学品经营许可证（带存储）