JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 135
·期 13
·46036
·
IF 1.86
Yanfang Hu,Weiqian Ma,Meilin Tao,Xueyan Zhang,Xiaohong Wang,Xiaoyu Wang,Li Chen
Herein, we present a strategy for supporting bromine as a catalyst for the oxidation of sulfides. In this strategy, branched poly(ethylene imine) was first decorated by magnetic oxide and then used to support liquid bromine to obtain solid polymeric bromine (M@PEI@Br) nanoparticles. Compared with free bromine, the stability of the M@PEI@Br nanoparticles improved obviously. The oxidation of thioanisole to methyl phenyl sulfoxide was chosen as a reaction model to evaluate the catalytic activity of the M@PEI@Br nanoparticles. All of the obtained results verify that the M@PEI@Br nanoparticles exhibited excellent catalytic efficiency and could accelerate the oxidation process under solvent-free conditions at room temperature; this highlighted the potential of decorated polymers to support active and unstable small-molecule organic catalysts. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46036.
研究领域:
催化化学
·
高分子材料
·
纳米科技
·
有机合成
·
绿色化学
✓ 已验证
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Jian Qiao,Xiang-Ming Hu,Yun-Tao Liang,Qian Zhang,Wei Wang,Yan-Yun Zhao,Shuang Ju,Fu-Chao Tian
In order to improve the stability time and foaming ratio of gel foam, and change the traditional preparation method of gel foam. In this paper, using super-hydrophobic nanoparticles , PVA, sodium tetraborate and sodium bicarbonate as the main raw materials, based on the self-assembly effect of super-hydrophobic nanoparticles and hydrophilic macromolecules, a high-foaming gel foam (PGF) without foaming agent was prepared. Through the test, the foaming volume of the 100 ml PGF can reach 329 ml without adding foaming agent, which is 1.4 times of the traditional gel foam (TGF) and 1.2 times of the viscous foam (VF). Even without foaming agent, the PGF has a half-life of more than 13 days and can retain water for more than 15 h at 100 °C. Response surface analysis showed that the foaming performance of the PGF was affected by nanoparticles, sodium tetraborate and sodium bicarbonate, among which the content of nanoparticles was the main factor. At the same time, sodium tetraborate and sodium bicarbonate also significantly affect the water retention performance of PGF. Fire prevention experiments show that the gel foam prepared by this method also has excellent fire prevention ability, which can effectively inhibit the consumption of hydroxyl group and the generation of methyl and methylene group in the process of coal oxidation. Moreover, it can still play an inhibiting ability at a high temperature of 400 °C, and can effectively prevent the recurrence of coal fire after extinguishing. The development of PGF provides a new method for the preparation of gel foam in the future. At the same time, the application of foaming agent is avoided, which reduces the pollution of surfactant to the environment.
研究领域:
材料科学
·
消防工程
·
能源安全
·
高分子化学
·
界面科学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2018
·Vol. 43
·期 14
·7038-7045
·
IF 4.229
Rui Lu,Min Hu,Caili Xu,Yi Wang,Yun Zhang,Bin Xu,Daojiang Gao,Jian Bi,Guangyin Fan
Developing effective catalysts for hydrogen evolution from hydrolysis of ammonia borane (AB) is of great significance considering the useful applications of hydrogen. Herein, graphitic carbon nitride (g-C 3 N 4 ) prepared through the simply pyrolysis of urea was employed as a support for Rh nanoparticles (NPs) stabilization. The in-situ generated Rh NPs supported on g-C 3 N 4 with an average size of 3.1 nm were investigated as catalysts for hydrogen generation from the hydrolysis of AB under mild conditions. The Rh/g-C 3 N 4 catalyst exhibits a high turnover frequency of 969 mol H 2 · (min·mol Rh ) −1 and a low activation energy of 24.2 kJ/mol. The results of the kinetic studies show that the catalytic hydrolysis of AB over the Rh/g-C 3 N 4 catalyst is a zero-order reaction with the AB concentration and a first-order reaction with the Rh concentration. This work demonstrates that g-C 3 N 4 is a useful support to design and synthesis of effective Rh-based catalyst for hydrogen-based applications.
研究领域:
催化化学
·
能源材料
·
纳米催化
·
氢能源
·
反应动力学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2017
·
IF 3.133
Haibo Wu,Yinsheng Li,Shan Yun,Xuejian Liu,Zhengren Huang,Dongliang Jiang
Porous gelcasted and solid-state-sintered SiC (S-SiC) ceramics with significantly improved connectivity were successfully prepared through the synergistic pore-forming mechanism of direct foaming and particle packing, using fine (D 50 = 0.5 μm) and coarse (D 50 = 5.0 μm) graded SiC powders as the main raw materials. As the proportion of coarse SiC powder increased, the viscosities of aqueous SiC-B 4 C-C slurries sharply decreased, which thus flourished foaming and enlarged bubble-derived-pore diameter in porous S-SiC ceramics, accompanied with the increased amount and size of window. Moreover, abundant particle-packing pores in struts of bubble-derived pores were also formed and even interconnected with each other at 60 wt% of coarse SiC powder. Besides, there was a remarkable increase in porosity from 61.0% to 81.7% and accordingly a significant decline in density from 1.24 g cm −3 to 0.58 g cm −3 as the content of coarse SiC powder increased. The optimized multiple pore microstructures resulted in an amazing nitrogen gas permeability of 1.78×10 −11 m 2 under the condition of an excellent compressive strength of 10.8 ± 2.7 MPa.
研究领域:
材料科学
·
无机非金属材料
·
多孔陶瓷
·
陶瓷加工
·
结构-功能一体化材料
✓ 已验证
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2018
·
IF 3.193
Anna Zheng,Yongkang Huang,Yang You,Jian Hu,Dafu Wei,Xiang Xu,Yong Guan
The heat resistance enhancement of fluorosilicone rubber (FSR) can make it more suitable for cutting-edge applications and extreme conditions. This paper focused on the antioxidant properties of boron particles for FSR and the corresponding mechanism. The thermal stability of FSR and FSR/boron composites was characterized by thermal gravimetric analysis (TGA), isothermal degradation and thermal-oxidative ageing. The results showed that boron significantly improved the thermal stability of FSR. In particular, the FSR/boron (100/10) composite retained 95% of its weight after isothermal degradation at 350 °C for 12 h, while the FSR lost 55% of its weight within the initial 1 h. The antioxidant mechanism of boron was further investigated by chemiluminescence (CL), electron paramagnetic resonance (EPR) and vulcanization curves. It was shown that boron has powerful radical scavenging activity (RSA) and inhibited the oxidation scission of the side groups. Moreover, boron revealed no RSA towards the tert-butoxy radical, ensuring the good vulcanization of the FSR/boron composites.
研究领域:
高分子材料科学
·
橡胶化学
·
功能复合材料
·
热稳定性能
·
抗氧化机制
✓ 已验证
DOI
高影响因子
FOOD CONTROL
·
2014
·
IF 2.819
Jingyue Xu,Ying Li,Jiajia Guo,Fei Shen,Yeli Luo,Chunyan Sun
A new fluorescence method for detecting clenbuterol based on gold nanoparticles (AuNPs) and rhodamine B (RB) has been developed. It has been observed that the quenching of fluorescence of RB occurs in the present of AuNPs through the fluorescence resonance energy transfer (FRET). In the presence of clenbuterol , the FRET-based fluorescence of RB and AuNPs would be gradually recovered for the reason that clenbuterol could congregate the AuNPs and inhibit the FRET process . An assay for the determination of clenbuterol has been proposed based on the modulation in FRET efficiency between RB and AuNPs. Under the optimum conditions, the fluorescence recovery efficiency of the assay is proportional to the concentration of clenbuterol. The detection limit in swine feed was calculated to be 0.008 mg/g and the recoveries were in the range of 97%–102%. In short, the proposed method provides advantages such as rapidity, simplicity, low cost and high sensitivity, making it promising for the rapid screening of clenbuterol residues.
研究领域:
分析化学
·
纳米生物技术
·
药物残留检测
·
食品安全
·
分子诊断
✓ 已验证
DOI
高影响因子
MATERIALS LETTERS
·
2013
·
IF 2.224
Kejie Yu,Xuebin Zhang,Hongwu Tong,Xiangyan Yan,Shaomin Liu
Fibrous monodisperse core–shell structured Fe 3 O 4 /SiO 2 /KCC-1 nanoparticles were synthesised successfully through a surfactant-templated microemulsion formation process. The structure and morphology of the synthesised nanoparticles were investigated by scanning electron microscopy , transmission electron microscopy , superconducting quantum interference device susceptometer, X-ray diffraction, thermogravimetric analysis and N 2 adsorption/desorption. These nanoparticles showed monodisperse spherical morphology, high magnetism , good thermal stability , large surface area , direct channels, easily accessible large pores and narrow size distribution. A mechanism for the synthesis of these nanoparticles was proposed and explained. Adsorption experiments indicated that the as-prepared materials had good adsorption capacity for dye and could perform a fast transfer of molecules, indicating its promising application in purification of industrial wastewater, drug delivery and so on.
研究领域:
纳米医学
·
材料科学
·
环境工程
·
生物材料
·
药剂学
·
胶体与界面化学
✓ 已验证
DOI
高影响因子
DYES AND PIGMENTS
·
2017
·
IF 3.473
Yijun Zhang,Jiaqi Zhang,Junwen Zhang,Sai Lin,Yunyun Huang,Rongrong Yuan,Xiaojuan Liang,Weidong Xiang
A novel gold-carbon dots (GCDs) exhibiting relatively high luminescence have been successfully synthesized by a facile solution cast method. Intriguingly, colloidal Au nanoparticles (Au NPs) present an enhancement effect on the photoluminescence of CDs, which can be attributed to the metal enhanced fluorescence (MEF) included two cooperative mechanisms and near-field interactions. Significantly, the 1.5–3 fold enhancement was obtained in the vicinity of Au NPs. The formation mechanism and chemical structure of the as-prepared GCDs were verified by a series of characterization techniques, such as high-resolution transmission electron microscope (HRTEM), Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The GCDs with optimal fluorescence was acquired by varying volume ratio of colloidal Au NPs to CDs, rendering bright visible light under 460 nm excitation and high quantum yield (QY) of 39%. Given that, a simple spin coating technology was developed for fabricating GCDs film composed of GCDs solution and quartz glass. Subsequently, GCDs-based white light emitting diodes (white LED) was designed through integrating blue LED chips with the yellow light-emitting GCDs film. In addition, the GCDs film at appropriate thickness possesses excellent optical performances with the corresponding optimized color coordinate (CIE) of (0.33, 0.36), the color rendering index (CRI) of 78.2, correlated color temperature (CCT) of 5653 K, and the luminous efficiency (LE) approaching to 43.75 lm W −1 . These superior results demonstrate that GCDs constitute a versatile and effective route for achieving high-performance white LED.
研究领域:
材料科学
·
纳米技术
·
光电子学
·
发光材料
·
半导体器件
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·Vol. 50
·期 14
·24995-25004
·
IF 5.1
Zhiyi Li,Haili Sun,Wei Wei,Fengxia Liu,Xiaofei Xu,Zhijun Liu
The emerging market of high-power lithium-ion batteries (LIBs) highlights the importance of developing high-voltage cathodes. Lithium nickel phosphate (LiNiPO 4 ) with the highest theoretical discharge potential (∼5.1V) has attracted increasing attention due to its stable olivine structure. In this study, ultrathin carbon layer-coated LiNiPO 4 was synthesized using oleylamine-assisted solvothermal method under different solvothermal times, and the effect of solvothermal time (1h–18h) on LiNiPO 4 samples is fully investigated. X-ray diffraction (XRD) shows that high-purity LiNiPO 4 materials can be prepared after calcination of the solvothermal product under N 2 , but adding part of H 2 to the calcination atmosphere will lead to the generation of impurities in the target product. As the solvothermal time increases, the product will agglomerate and grow, the particle size will increase, and the morphology will change from nanoparticle to rodlike structure. After the high-temperature calcination step, the oleylamine is completely carbonized, and a conductive carbon layer is successfully coated on the LiNiPO 4 with the thickness of 2 nm. As the solvothermal time increases, the graphitization degree of oleylamine increases after carbonization. The existence of the carbon layer and the increase in the degree of graphitization are beneficial to improving the electrical conductivity and Li-ion diffusion rate of LiNiPO 4 . The initial discharge capacity of LNP@C-12h product prepared with 12 h solvothermal time is 35 mA h g −1 at 0.1 C. Rietveld analysis shows that the anti-site defect concentration of the LNP@C material is 1.07 %, and the proportion increases to 2.83 % after several cycles. This work provides a positive contribution to the synthesis and modification of high-voltage LiNiPO 4 materials and explains the electrochemical performance degradation of LiNiPO 4 from the perspective of increasing the concentration of anti-site defects.
研究领域:
材料科学
·
电化学
·
纳米科技
·
能源存储
·
锂离子电池
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2019
·
IF 4.561
Yanting Wang,Youmin Sun,Shengying Gong,Zhengqing Cai,Jie Fu
Silver nanoparticles (AgNPs) are one of the main nano-contaminants and their entry into the environment may pose a threat to the aquatic ecosystems . Meanwhile, AgNPs have an important impact on geological processes . In this paper, we studied the influence of AgNPs on the sedimentation of suspended sediments . Results showed the settling rate of sediments increased from 13.06 to 20.08 h −1 in the presence of 0.2 mg/L AgNPs. The morphology characterization indicated the average particle size of sediments increased from 34.74 to 42.87 μm after interacting with AgNPs, resulting in the acceleration of settlement on the basis of Stokes' law. The chemical analysis detected 43–57% of AgNPs were incorporated onto sediments, which was the dominant reason for the increased sediments size and settling rate. The influences of various water quality parameters, e.g., pH, ionic strength , temperature, humic acid and surfactant , on the sediments settlement and interaction with AgNPs were comprehensively studied. Elevating the solution pH, ionic strength, temperature, contents of humic acid and anionic/nonionic surfactants would suppress the settling of suspended sediments , whereas cationic surfactant showed a promoting effect on sediments settlement. In addition, the settling experiments were conducted in collected lake water and seawater , and results showed the real water matrices hindered the sediments settlement and interaction with AgNPs.
研究领域:
环境科学
·
地球化学
·
水体生态学
·
纳米毒理学
·
沉积学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
·
2016
·Vol. 42
·期 7
·3947-3954
·
IF 3.205
Jialei Jin,Yuanzhi Zhu,Yizhe Liu,Yang Li,Wenchao Peng,Guoliang Zhang,Fengbao Zhang,Xiaobin Fan
Producing hydrogen through hydrogen evolution reaction by electrolyzing water is a great alternative to solve the energy crisis and air pollution. Earth abundant transition-metal phosphides, especially CoP , have emerged as promising hydrogen evolution reaction catalysts for recent years. Nowadays, attention is focused on combining CoP with other materials to improve its catalytic activity . Herein, in order to get better hydrogen evolution reaction catalyst, we combined CoP nanoparticles with WS 2 nanosheets. Different CoP to WS 2 mass ratios were set to find the best catalytic activity. CoP/WS 2 composites were prepared through a simple ultrasound induced mixing method. And all the CoP/WS 2 composites have enhanced hydrogen evolution reaction catalytic activity than pure CoP nanoparticles and WS 2 nanosheets. Especially, the optimized CoP/WS 2 composite has the lowest onset overpotential of 50 mV, the largest current density of 78 mA/cm 2 at the overpotential of 300 mV, and the smallest Tafel slope of 64.63 mV/decade, indicating excellent hydrogen evolution reaction catalytic activity.
研究领域:
材料科学
·
电化学
·
纳米催化
·
能源材料
·
无机功能材料
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2016
·Vol. 42
·期 6
·7767-7773
·
IF 2.758
Shuangbing Li,Jixiao Wang,Song Zhao,Wei Cai,Zhi Wang,Shichang Wang
The unmodified and 3-(trimethoxysilyl) propyl methacrylate (TPM) modified silica nanoparticles were synthesized via the modified Stöber method. The structure and chemical composition of silica nanoparticles were determined by scanning electron microscope (SEM), X-ray diffraction (XRD) characterization, Fourier Transform Infrared Spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results demonstrate that silica nanoparticles with the diameter of 90 nm and amorphous state are successfully modified by TPM. The rheological test results demonstrated that surface modification of nanoparticles and medium exerted great influence on the rheological properties of silica particle suspension. Under high shear rate of about 250 s −1 , the viscosity of suspension comprising unmodified silica nanoparticles and deionized water , TPM-modified silica nanoparticles and deionized water, TPM-modified silica nanoparticles and polyethylene glycol , is about 0.4 Pa.s, 0.1 Pa.s and 30 Pa.s, respectively. The results are significant for preparing homogenous and stable silica nanoparticle suspension, and meaningful for ceramic processing .
研究领域:
材料科学
·
纳米技术
·
陶瓷加工
·
胶体化学
·
高分子材料
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）