MICROPOROUS AND MESOPOROUS MATERIALS
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2020
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IF 4.551
Di Wang,Erjun Sun
In this paper, a sensing probe (denoted as CFE) for tumor-biomarker 5-hydroxyindoleacetic acid (5-HIAA) was firstly synthesized. Its sensing mechanism was confirmed as the recovery of fluorescein structure via an ester-exchange reaction, accompanied with emission turn on effect towards 5-HIAA. To improve photostability and minimize self-quenching/aggregation of CFE molecules, they were loaded into silica based MCM-41 spheres and UCNPs-cored (up-conversion nanoparticles) MCM-41 spheres. Corresponding composite samples, denoted as CFE@MCM-41 and CFE@MCM-41@UCNPs, were carefully discussed to confirm their structure, including XRD , N 2 adsorption and desorption, SEM/TEM and TGA . The energy transfer from secondary excitation source UCNPs to probe CFE was confirmed by Forester radius calculation and emission lifetime comparison. Sensing performance of CFE@MCM-41 and CFE@MCM-41@UCNPs were finally discussed in detail. They showed emission turn on effect towards 5-HIAA with good selectivity. CFE@MCM-41 showed linear response, while CFE@MCM-41@UCNPs showed exponential response, resulting in a warning signal when analyte concentration was higher than a critical level. The reason for this exponential response was discussed and explained. Their practical sensing result for human urine test was compared to HLPC method and literature methods, which confirmed the promising result of CFE@MCM-41 and CFE@MCM-41@UCNPs.
研究领域:
生物化学
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医学诊断
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
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2018
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IF 0
Zhejian Wu,Rong Chen,Qimao Gan,Jian Li,Tuqiao Zhang,Miaomiao Ye
Mesoporous Na + SiO 2 spheres with large surface areas, high porosities and tunable Na + contents have been synthesized by the Stöber method followed by the “polyvinylpyrrolidone (PVP)-protected NaOH etching” process. With the surface protection of PVP, the NaOH etching preferentially occurs inside the SiO 2 spheres results in the increase of the surface areas and porosities of the SiO 2 spheres while keeping the sphere size unchanged at the etching degree less than 50%. The surface area and pore volume of the selected Na + SiO 2 spheres with etching degree of 50% are 302.9 m 2 /g and 0.946 cm 3 /g, respectively, which are 31 times and 59 times higher than that of the SiO 2 spheres without NaOH etching. The Na + SiO 2 spheres with etching degree of 10% calcined at 400 °C shows high adsorption activity for Cr 3+ removal from different natural waters such as tap water, lake water and river water. The adsorption kinetic of Cr 3+ by the Na + SiO 2 spheres fits well with the pseudo-second-order model, and the adsorption isotherm can be fitted by the Langmuir adsorption isotherm. The maximum adsorption capacity of 10% Na + SiO 2 400 for Cr 3+ is 33.18 mg/g. Finally, it has been confirmed that the ion-exchange between Na + and Cr 3+ plays the leading role in the adsorption process while the contribution from static adsorption is relatively weak.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
SEPARATION AND PURIFICATION TECHNOLOGY
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2020
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IF 5.774
Mingyang Zhou,Junchao Chen,Wenjin Zhou,Juan Sun,Hongyan Tang
Membrane fouling is still an inevitable main challenge to nanofiltration (NF) process, which leads to a decline in membrane performance. Inspired by fish scales, a facile method was performed to develop composite NF membranes with highly stable antifouling property based on hydrophilic roughness. γ-(2,3-glycidyloxy) trimethoxysilane (KH560) grafted onto PEI molecules during interfacial polymerization on hydrophilic microporous PTFE support. Finally, tetraethyl orthosilicate (TEOS) reacted with KH560 molecules. Results of fourier transform infrared (FTIR) spectra, FESEM and contact angle measurements indicated that micro/nano hydrophilic SiO 2 spheres engendered on the membrane surface. Evaluation of membrane antifouling property showed that flux recovery ratio (FRR) of BSA, HA, SDS and Oil/water mixture for the as-prepared NF membranes were 96.0%, 95.8%, 96.8% and 95.0%, respectively. No obvious permeate flux decline and rejection fluctuation could be observed in filtration experiment of MgSO 4 aqueous solution on long-term run (100 h). It indicated highly stable antifouling property, which may be due to hydrophilic microscale/nanoscale SiO 2 spheres grafted onto the skin layer of the as-prepared NF membranes through chemical linkage. It is expected that these findings could provide more insight for fabrication and simultaneous modification of NF membranes.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
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2020
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IF 3.83
Li Li,Xinhong Chen,Xia Xiong,Xiaoping Wu,Zinan Xie,Zuohua Liu
The development of a simple and environmentally friendly method to synthesize hollow TiO 2 structures is urgent for realizing high NIR reflectance and low thermal conductivity . Hollow TiO 2 @SiO 2 structures have been successfully synthesized by a recycling template method. The synthesis process involves four steps as follows: 1) preparation of SiO 2 spheres, 2) synthesis of SiO 2 @TiO 2 core-shell structure by coating mesoporous TiO 2 shell on SiO 2 and crystallization by calcination , 3) etching the SiO 2 @TiO 2 to form the hollow TiO 2 spheres, and 4) coating the hollow TiO 2 spheres with a SiO 2 protection layer to produce hollow TiO 2 @SiO 2 structures. The SiO 2 serves as a template to support and synthesize hollow TiO 2 shell, and then after being etched, to form a Na 2 SiO 3 solution as a coating agent to protect TiO 2 shell from photocatalytic activity. The as-synthesized hollow TiO 2 @SiO 2 structures not only have high NIR reflectance, but also have a high thermal barrier performance due to the hollow structure. Moreover, the NIR reflectance of the coating made from hollow TiO 2 @SiO 2 reached 94.9%, and the temperature of the inner surface of the coating board is reduced about 16 °C, compared with the surface without coating. The weather resistance studies reveal that the hollow TiO 2 @SiO 2 sample is very stable under the UV irradiation. In particular, the hollow TiO 2 @SiO 2 structures synthesized by using this method shows multifunctional responses towards solar heat.
研究领域:
材料科学
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纳米技术
✓ 已验证
DOI
高影响因子
JOURNAL OF CATALYSIS
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2022
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IF 8.047
Yan Wu,Ling-Hui Kong,Wen-Ting Ge,Wen-Jie Zhang,Zhen-Yue Dong,Xiao-Jing Guo,Xi Yan,Yan Chen,Wan-Zhong Lang
A porous V/SiO 2 sphere composite (VO X @SiO 2 ) was synthesized using one-step sol-gel method. Benefiting from the redox properties of vanadium and the hydrophilic property, VO X @SiO 2 showed good catalytic performances for the selective oxidation of benzyl alcohol (BzOH) to benzaldehyde (BzH) in aqueous phase through peroxymonosulfate (PMS) activation, and performed far better in water than in various organic solvents. The redox cycle of V V /V IV was supposed to be responsible for PMS decomposition in the VO X @SiO 2 /PMS system. The S O 4 ∙ - , 1 O 2 and mediated electron transfer were revealed to play a major role in the selective oxidation of BzOH to BzH. The intrinsic kinetics was analyzed to calculate the chemical reaction rate (r a ) and reaction order (n = 0.33) with respect to BzOH. This study provided some insights into the development of vanadium-based heterogeneous catalyst for the selective oxidation of BzOH to BzH through PMS activation.
研究领域:
化学工程
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催化材料科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）