MICROPOROUS AND MESOPOROUS MATERIALS
·
2020
·
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
·
医学诊断
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2024
·
IF 3.8
Yonghong Wu,Zhihang Shang,Zhaorui Li,Wenle Zhu,Lifang Nie,Juncheng Liu
Sol-gel is one of the most economical methods to prepare antireflection films, but the low ultraviolet radiation-resistance (UV-resistance) of the sol-gel film limits its applicability in the solar industry. A SiO 2 antireflection film was prepared with sol-gel method with phenyl salicylate (PS) as the porogen. The effects of the PS addition were investigated on the microstructure, optical property and UV-resistance of the film. When the addition of PS is 1.20 g, the refractive index at 550 nm is 1.30, and the maximum transmittance is 96.30 %. The average transmittance within the 400–1100 nm range reaches its peak at 92.85 %, which is 4.35 percentage points higher than that of the blank glass. In addition, the film without PS has an average transmittance of 91.00 % after 5000 equivalent solar hours (ESHs) UV irradiation, decreasing 1.07 percent point, and has a pencil hardness of 5 H and an adhesion of grade 2 of the tape-tearing method. However, the film with 1.20 g of PS still has an average transmittance of 92.15 % after 5000 ESHs UV irradiation, decreasing only 0.7 percent point, and has a pencil hardness of 7 H and an adhesion of grade 1 of the tape-tearing method.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC
·
2015
·
IF 2.128
Chuan-Yang Shang,Wei-Xun Li,Feng Jiang,Rui-Feng Zhang
ZnO nanowires/macroporous SiO 2 composites were used as a new type of microwave absorbing support to immobilize Candida rugosa lipase (CRL). Under microwave irradiation the immobilized lipase was used to catalyze esterification of phytosterol and oleic acid for the synthesis of phytosterol esters. A great improvement of the catalytic activity was found in the systems in which composited ZnO nanowires were present. The microwave absorbing properties of ZnO nanowires have been proved to be helpful for the synergistic effect between microwave irradiation and enzyme catalysis. The immobilized CRL showed higher thermal stability at 55 °C under microwave irradiation than conventional heating. A maximum molar conversion of 95.4% under microwave irradiation was achieved under the optimal condition: 0.1 M phytosterol, 0.2 M oleic acid, water activity ( a w ) of 0.11, reaction temperature at 50 °C and reaction time of 1 h.
研究领域:
生物化学
·
酶工程
·
纳米材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2023
·
IF 7.4
Liping Du,Binfei Li,Teng Lu,Boliang Li,Zhaomin Li,Jiqian Wang
To address problematic low reservoir recovery rates, a new porous SiO 2 aerogel nanosuspension (NS) with emulsifying effects was developed, and its microstructure and flow characteristics were analysed with physical property and rheological tests. Moreover, macro- and microlevel flooding experiments were carried out to explore the mechanism for enhanced oil recovery (EOR). The results showed that the final recovery rates were 58.23% and 60.68% with 0.8 PV NS and NS foam slug, respectively, which were 10.03% and 13.62% higher than those of secondary oil recovery. Oil-water emulsions with different emulsification degrees were generated after sufficiently oscillating the NS and condensate oil mixture. NS flooding exhibited evident nonpiston characteristics in the early stage, and particles were transferred from water into the oil phase, which resulted in differential emulsification of the oil. The oil flow status was altered from flakes to droplets due to emulsification and the changing passage cross-section caused by particle accumulation. With NS foam flooding, the oil was first replaced by coherent large bubbles and then migrated under the effects of multiple systems. A particle circumfluence layer around the foam absorbed oil to generate an adhesive oil film.
研究领域:
石油工程
·
材料科学
·
流体力学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2016
·
IF 3.138
Huaiyan Sun,Xinyu Jin,Nengbing Long,Ruifeng Zhang
A ZnO nanowires/macroporous SiO 2 composite was used as support to immobilize horseradish peroxidase (HRP) by in-situ cross-linking method. Using diethylene glycol diglycidyl ether (DDE) as a long-chained cross-linker, it was adsorbed on the surface of ZnO nanowires before reaction with HRPs, the resulted composite was quite different from the traditional cross-linking enzyme aggregates (CLEAs) on both structure and catalytic performance. The immobilized HRP showed high activity in the decolorization of azo dyes. The effect of various conditions such as the loading amount of HRP, solution pH, temperature, contact time and concentration of dye were optimized on the decolorization. The decolorization percentage of Acid Blue 113 and Acid black 10 BX reached as high as 95.4% and 90.3%, respectively. The immobilized HRP gave the highest decolorization rate under dye concentration as 50 mg/L and reaction time of 35 min. The immobilized HRP exhibited much better resistance to temperature and pH inactivation than free HRP. The storage stability and reusability were greatly improved through the immobilization, from the decolorization of Acid blue 113 it was found that 80.4% of initial efficiency retained after incubation at 4 °C for 60 days, and that 79.4% of decolorization efficiency retained after 12 cycles reuse.
研究领域:
生物化学
·
环境科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 19
·52115
·
IF 3.057
Chuying Zhang,Hang Zhao,Fan Yang,Na Zhang,Tongguang Zhu,Kunyue Leng,Jinbo Bai
The addition of inorganic particles can endow polymer matrices with different new features, thereby realizing an optimization to the structural and functional properties of composite. The overall properties of composites are greatly influenced by both fillers dispersion and fillers-polymer interfacial interaction. However, to simultaneously improve these mentioned two issues is still a critical challenge in the field of polymer-based nanocomposite. Herein, a typical core-shell structured mesoporous silica-coated silica (SiO 2 @mSiO 2 ) construction was successfully synthesized by using a bi-phase method. The SiO 2 @mSiO 2 filled polyethylene (PE) nanocomposite was fabricated through a precisely controlled melt-mixing approach. Benefiting from the additional mesoporous SiO 2 shell, both the dispersion of SiO 2 @mSiO 2 and the SiO 2 @mSiO 2 -PE matrix interfacial interaction are improved. Moreover, the stress–strain behavior, temperature-dependent mechanical property, thermal stability, and electrical insulating property of SiO 2 @mSiO 2 /PE composite were studied in detail. It is found that SiO 2 @mSiO 2 core-shell nanoparticles are capable of not only making a balance between the strength and toughness of the PE-based composite, but also improving the thermal stability of the composite. In addition, the SiO 2 @mSiO 2 /PE composite exhibited an enhanced breakdown strength (256.4 MV·m −1 ) when filled with as small as 1 wt% SiO 2 @mSiO 2 , which is 108% higher than neat PE. All these optimized features are attributed to the well-designed core-shell structure. These experimental results provide a promising way to design and fabricate future advanced composite with excellent structural and functional properties in the future.
研究领域:
材料科学
·
高分子科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2021
·
IF 5.097
Yanna Lin,Yulong Xu,Yanzhi Xing,Nazhen Liu,Xuwei Chen
A three-dimensional ordered macroporous composite (3DOM SiO2@ZIF-8-TBA) was fabricated via the in situ growth of metal–organic framework ZIF-8 (∼50 nm) on the surface of macroporous SiO2 (pore size of ∼250 nm) and the subsequent functionalization with a thrombin aptamer. The obtained 3DOM SiO2@ZIF-8-TBA composite has been proven to be a potential protein-enriching adsorbent, which exhibits high selectivity toward the adsorption of thrombin due to the specific conformation between the aptamer and thrombin. The adsorption behavior of thrombin onto the 3DOM SiO2@ZIF-8-TBA composite conforms to the Langmuir adsorption model, resulting in a superior adsorption capacity of 40.9 U mg–1, contributed by the ordered macroporous structure. The retained thrombin could be readily recovered by 1.0% NH3·H2O (m/v) with a recovery of 92.3%. Circular dichroism spectra illustrate that the 3DOM SiO2@ZIF-8-TBA composite-based adsorption/desorption processes have no influence on thrombin conformation. The application of the 3DOM SiO2@ZIF-8-TBA composite in separating thrombin from human serum has been verified; fibrin production tests prove that the activity of recovered thrombin is well retained.
研究领域:
材料科学
·
生物化学
·
纳米技术
·
分析化学
✓ 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）