LANGMUIR
·
2021
·
IF 3.882
Yixian Luo,Dou Jin,Wenjin He,Jianzhong Huang,Aicheng Chen,Feng Qi
The opal-like SiO2 microcarriers with different pore diameters named opal-SiO2I and opal-SiO2II were synthesized and utilized as microcarriers to immobilize Rhizopus oryzae lipase (ROL) and Aspergillus oryzae α-amylases (AOA). ROL and AOA can be more stably immobilized on the cross-linked SiO2 opals by neopentyl glycol diglycidyl ether (NGDE), which is the first attempt to use it as a cross-linking agent compared with glutaraldehyde. According to the morphology analysis, multiple layers of SiO2 monodisperse microspheres were regularly packed and formed an opal-like structure, and enzymes were well scattered and immobilized throughout the SiO2 opals. The results showed that the performance of enzymes immobilized on opal-SiO2II with a larger specific surface area was much better than that of opal-SiO2I. The enzyme activity of ROL@opal-SiO2II and AOA@opal-SiO2II cross-linked with 1% NGDE increased 5.32 and 9.32 times compared with their free counterpart, respectively. Furthermore, pH and thermal stability and reusability of ROL/AOA@opal-SiO2II were significantly improved and higher than those of ROL/AOA@opal-SiO2I and free enzymes. This study provides an easily obtained microcarrier opal-SiO2II, which shows potential for efficient different enzyme immobilizations and further industrial applications.
研究领域:
生物化学
·
材料科学
·
酶工程
✓ 已验证
DOI
PubMed
高影响因子
MICROCHIMICA ACTA
·
2017
·Vol. 184
·期 7
·2241-2248
·
IF 4.58
Zhang Yufeng,Zhou Zhiping,Zheng Jiahong,Li Hongji,Cui Jiuyun,Liu Siwei,Yan Yongsheng,Li Chunxiang
The authors describe a fluorescence based assay for determination of the macrolid antibiotic erythromycin (ERY). It is based in the use of fluorescent gold nanoclusters (AuNCs) coated first with silica (to obtain AuNC@SiO 2 ) and then with a molecularly imprinted polymer (MIP). The MIP was synthesized from 3-aminopropyltriethoxysilane as the functional monomer, ERY as the template, and tetraethoxysilane as the cross-linker via a sol-gel process that leads to surface imprinting. By using this method, the strong fluorescence of AuNCs was maintained in the resultant MIPs. After optimization of the experimental conditions, the signal (measured at excitation/emission wavelengths of 396/585 nm) decreases linearly with increasing concentration of ERY in the 0.1 to 11.9 μM ERY concentration range. The limit of detection is 12 nM, and the imprinting factor is 4.0. The method was successfuly applied to the determination of ERY in spiked human urine and saliva.
Schematic of the preparation of a core-shell sensor material with the silica coated by fluorescent gold nanoclusters as core and a molecularly imprinted polymer. It can be used to selectively detect residual erythromycin in biological samples.
研究领域:
分析化学
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纳米技术
·
生物传感器
·
药物分析
✓ 已验证
产品关联
DOI
高影响因子
THIN-WALLED STRUCTURES
·
2022
·
IF 5.881
Danna Tang,Kai Yang,Tianyu Gao,Tingting Liu,Haibin Tang
Mechanical-electromagnetic integrated design has great potential in the development of electromagnetic shielding equipment for military use. In this study, Al 2 O 3 /SiO 2 ceramics with triply periodic minimal surfaces (TPMSs) were fabricated using digital light processing (DLP) technology. The preparation of SiO 2 and Al 2 O 3 powders is vital for DLP because minimal aggregates or sedimentation in the ceramic paste is required. Debinding and sintering programs were developed to prevent defects in the designed microstructure. The interfacial characterization demonstrated that the surfaces of the sintered ceramics were compact and smooth. The compression strength of the TPMS ceramic with a volume fraction of 50% was 24 MPa, which is relatively good among additively manufactured cellular ceramics. The TPMS structures also exhibited significant electromagnetic interference (EMI) shielding effectiveness in the X-band (2 to 18 GHz), and the shielding performance was adequate to meet the demands of electromagnetic shielding materials . Additive manufacturing of Al 2 O 3 /SiO 2 ceramic with TPMS architectures was successfully achieved by considering the mechanical-electromagnetic integration.
研究领域:
材料科学
·
电磁学
·
增材制造
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2019
·
IF 3.131
Xuechen Tang,Bobo Zhou,Chao Chen,Bauyrzhan Sarsenbekuly,Hongbin Yang,Wanli Kang
Due to the superior performance caused by surface modification and combined effects, polymer/nano-SiO 2 composites have been studied systematically for a long term and attracted increasing academic and industrial interests, especially in the petroleum engineering field. However, few works have been done on the mechanism that how the functional modification degree ( MD ) of nano-SiO 2 influences on the properties of the composites. In this work, a series of 3-(methacrylyloxy)propyltrimethoxysilane (MPS) modified nano-SiO 2 particles with different MD s were prepared and found to differ largely from each other in macroscopic properties . Then the effects of SiO 2 MD on the physicochemical property and the enhanced oil recovery (EOR) capacity of the corresponding polymer/nano-SiO 2 composite microspheres (PNSCMs) for the conformance control in oilfields were investigated in detail. The results clarified that by regulating the MD of nano-SiO 2 encapsulated in PNSCMs, the swelling property, viscoelasticity , mechanical strength and dispersion stability were significantly improved. Compared with traditional chemical copolymer microspheres CPMs, PNSCMs exhibited better conformance control and EOR ability, which was further improved as SiO 2 MD increased. The maximum oil recoveries of cores treated by PNSCMs were 76.14% and 52.45% in the experiment, and the EOR increased by 5.99% and 4.99% than those treated by CPMs, respectively, under homogeneous and heterogeneous conditions.
研究领域:
石油工程
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Li Guo,Kai Lai Zhang,Huidong Shen,Chan Wang,Qiang Zhao,Danjun Wang,Feng Fu,Yucang Liang
Exploiting highly efficient and stable photocatalysts for treating Cr(VI)-containing wastewater is of great importance. Herein, a robust core-shell structurally magnetic Fe 3 O 4 @SiO 2 /Bi 2 WO 6−x F 2x photocatalyst was successfully fabricated and used to photocatalytic Cr(VI) reduction, in which an inert protective layer (SiO 2 )-coated micro/nanostructured Fe 3 O 4 particles can not only improve the chemical stability but also retain magnetic advantage of catalyst. The optimized 55% Fe 3 O 4 @SiO 2 /Bi 2 WO 6− x F 2 x exhibited the highest catalytic activity in a reaction system of pH = 3, the apparent rate constant (k app /min −1 ) of 55% Fe 3 O 4 @SiO 2 /Bi 2 WO 6−x F 2x for photocatalytic reduction of Cr(VI), as high as 0.027 min −1 , is approximately 5.4 and 2.6 times higher than that of Bi 2 WO 6 and Fe 3 O 4 @SiO 2 /Bi 2 WO 6 , respectively. After being illuminated for 90 min, nearly 100% percentage of Cr(VI) has been reduced to Cr(III) by using 55% Fe 3 O 4 @SiO 2 /Bi 2 WO 6−x F 2x as photocatalyst, which can be attributed to the synergistic effect of magnetic Fe 3 O 4 @SiO 2 support – “core”, Bi 2 WO 6 – “shell” and the successful introduction of F − ions. A readily magnetic separation of Fe 3 O 4 @SiO 2 /Bi 2 WO 6−x F 2x catalyst enabled it to reuse conveniently for practical industry application. Finally, the enhanced photocatalytic mechanism of catalyst was proposed for Cr(VI) reduction. The present study not only provides a new mean to solve the recovery of the Bi 2 WO 6 -based photocatalyst, but also presents a promising candidate for Cr(VI) reduction in the field of the industrial wastewater treatment.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2020
·
IF 0
Liujun Song,Jin Hu,Xiaofeng Huang,Li Zhong,Yongbing Pei,Lianbin Wu,Xinya Zhang
Inspired by the compound eye superhydrophobic phenomenon, the hemispherical particles with a concave (HPCs) were prepared and self-assembled into a similar array structure. To improve the roughness and mechanical durability properties, the nanoscale Fe2O3 nanorods modified by 1H,1H,2H,2H-perfluorodecyltriethoxysilane (FSA) were coated on the particles (HPC@Fe2O3) and then the SiO2 particles modified by FSA were deposited onto HPC@Fe2O3 arrays to mimic the nanoscale nipples of a compound eye. The obtained arrays show excellent superhydrophobic properties (the contact angle is 175°, and the sliding angle is 3.5°), which are mainly attributed to the stable micro/nanoscale air-cushion structure’s greatly reduced contact of water drops. After that, the self-healable poly(dimethylsiloxane) (NH2-PDMS) elastomer was introduced as a substrate, and the composite structure can be self-healed in 2 min at room temperature after being damaged, which greatly enhances the lifespan of the superhydrophobic film. This kind of biomimicry material combining the superhydrophobic with the self-healable property has promising applications in artificial skins, wearable devices, and so on.
研究领域:
材料科学
·
仿生学
✓ 已验证
产品关联
DOI
POLYMER BULLETIN
·
2020
·Vol. 78
·期 10
·5963-5976
·
IF 2.014
Gu Nianliang,Zhang Haiyan,Ge Heyi,Wang Feifei,Liu Bomin
We report a method of in-situ modification of phenolic resin (PR) on improving thermal stability with graphene/SiO 2 hybrids at an ultralow filler loading. GO/SiO 2 hybrids were prepared by electrostatic adsorption method and chemically reduced to RGO/SiO 2 hybrids by NaBH 4 . The effect of in-situ modification of PR by GO/SiO 2 and RGO/SiO 2 on thermal stability of PR was studied. The results of SEM, XRD and FTIR showed that the hybrids and in-situ polymerization had a significant effect on improving the thermal property of PR. The TG and DTG analyses demonstrated that the thermal performance of PR in 350–500 °C was improved prominently. The T 5% and T 10% of 0.1 wt% (RGO–SiO 2 )/PR were increased by 165.56 °C and 89.23 °C compared with the pure PR, reaching 381.77 °C and 466.20 °C, respectively. Moreover, the R 800°C of 0.1 wt% (GO–SiO 2 )/PR and 0.1 wt% (RGO–SiO 2 )/PR reached 69.86 wt% and 70.20 wt%, which increased by 10.75% and 11.29%, respectively, compared with pure PR. Therefore, the application of graphene/SiO 2 hybrids in the in-situ polymerization modification of PR can significantly improve the thermal stability of PR and broaden its application fields.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
IF 4.175
Yao Fu,Jian Li,Pengzhen Li,Huajie Tao,Xianfu Luo,Dongjian Wang,Yiting Shan,Hongqing Zhou
In this work, the titanate coupling agent KR-TTS was used in tape casting of CaO–B 2 O 3 –SiO 2 (CBS) glass-ceramics to obtain a high-performance dielectric tape. The functional group ((RO) m ) of KR-TTS could directly react with the hydroxyl (–OH) of the CBS powders, which made the feature of powders from hydrophilicity into hydrophobicity . The modification mechanism of the modifier KR-TTS was illuminated by infrared absorption spectrum and contact angle of powders with modifier KR-TTS. The optimum amount of KR-TTS was determined by the rheological properties of suspensions, the density and the tensile strength of the green samples, the density and dielectric properties of the sintering samples sintered at 835 °C. The surface modification of CBS glass-ceramic by KR-TTS has made a substantial breakthrough in improving the densification and the mechanical performance of the green tapes. When the amount of KR-TTS was 1.0 wt%, the stability of slurry and the properties of the green samples had been greatly improved. The density of the green samples with 1.0 wt% KR-TTS reached 1.59 g/cm 3 and the tensile strength of the green samples reached 2.43 MPa. The sintering sample with 1.0 wt% KR-TTS realized sintering densification and performed better dielectric properties. The sintering density reached to 2.51 g/cm 3 . The permittivity and dielectric loss were ε r = 5.92 and tanδ = 13 × 10 −4 at 10 GHz.
研究领域:
材料科学
·
无机非金属材料
·
电子材料
✓ 已验证
产品关联
DOI
高影响因子
ANALYST
·
2015
·Vol. 140
·期 19
·6684-6691
·
IF 4.107
Fengmin Qiao,Zhenzhen Wang,Ke Xu,Shiyun Ai
A facile process was developed for the synthesis of FeSe–Pt@SiO2 nanospheres based on the hydrothermal treatment of FeCl3·6H2O, selenium and NaBH4 in ethanolamine solvent, followed by reducing HPtCl4 with NaBH4 in the presence of FeSe particles to obtain FeSe coated with Pt NPs (FeSe–Pt), ending with a surfactant assembled sol–gel process to obtain FeSe–Pt@SiO2. The morphology and composition of FeSe–Pt@SiO2 were characterized by transmission electron microscopy, high resolution TEM, X-ray diffraction and Fourier transform infrared spectroscopy. Structural analyses revealed that FeSe–Pt@SiO2 nanospheres were of regular spherical shape with smooth surfaces due to the SiO2 shells, compared with FeSe particles with 150 nm lateral diameter. The prepared FeSe–Pt@SiO2 nanospheres possessed both intrinsic glucose oxidase (GOx-) and peroxidase-mimic activities, and we engineered an artificial enzymatic cascade system with high activity and stability based on this nanostructure. The good catalytic performance of the composites could be attributed to the synergy between the functions of FeSe particles and Pt NPs. Significantly, the FeSe–Pt@SiO2 nanospheres as robust nanoreactors can catalyze a self-organized cascade reaction, which includes oxidation of glucose by oxygen to yield gluconic acid and H2O2, and then oxidation of 3,3,5,5-tetramethylbenzidine (TMB) by H2O2 to produce a colour change. Colorimetric detection of H2O2 and glucose using the FeSe–Pt@SiO2 nanospheres was conducted with high detection sensitivities, 0.227 nM and 1.136 nM, respectively, demonstrating the feasibility of practical sensing applications. It is therefore believed that our findings in this study could open up the possibility of utilizing FeSe–Pt@SiO2 nanospheres as enzymatic mimics in diagnostic and biotechnology fields.
研究领域:
生物传感
·
纳米医学
·
酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTEGRATED FERROELECTRICS
·
2017
·
IF 0.457
Qi Tang,Li-Long Gao,Bing Yu,Hai-Lin Cong
ABSTRCTComposite materials show more superior performance compared with the single-component materials. Core-shell material as a new composite material are more and more widely used. TiO2@SiO2 core-shell microspheres belong to inorganic core-shell microspheres, compared with other types of core-shell material, the inorganic core-shell microspheres have advantage of controlled size, structural stability, easy surface modification, and so on. In the present paper, we demonstrated the synthesis of novel monodisperse core-shell microspheres with a TiO2 shell using a convenient process. Due to owning core-shell structures with TiO2 surface, the obtained TiO2@SiO2 microspheres can be used as photocatalysts.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Jiahao Wei,Jingtao Bi,Longfei Zhang,Dandan Han,Junbo Gong
Constructing a robust catalytic membrane with simultaneous fast liquid transport and efficient organic pollutant degradation is appealing for efficient organic wastewater treatment. Herein, Fe-doped CoTiO 3 grew uniformly on the SiO 2 fiber membrane to form a catalytic membrane (FCTSM). Benefiting from the great water wettability, FCTSM facilitated fast water transport with low energy consumption and exhibited high physical separation performance (98.4% rejection of oil in the emulsion). The catalytic active sites were fully exposed on membrane surface, which could easily react with peroxymonosulfate and target pollutants. Under the gravity-driven permeation, FCTSM performed decent catalytic degradation property (e.g., 96.3% removal of nimesulide with the flux of 300 L/m 2 ·h) in the presence of peroxymonosulfate. Electron paramagnetic resonance (EPR) spectra and quenching tests found that SO 4 •− and 1 O 2 were involved in pollutant degradation, and the possible degradation pathway of nimesulide was investigated. Besides, the toxicity analyses based on quantitative structure–activity relationship (QSAR) verified the reduced toxicity of degradation products. This work provides an insight into the design of multifunctional membranes and advances the potential applications of heterogeneous catalytic oxidation in environmental remediation.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Fang Chengqian,Dai Yimin,Chen Ling,Wang Zhiheng,Lu Qi,Li Yaqi,Cai Ling,Liu Bo,Zhang Yue-Fei,Li Yan,Wan Li
A magnetic Cl − -intercalated Fe 3 O 4 @SiO 2 @MgAl-Cl − LDH nanocomposite has been successfully synthesized by modified one-step salt-assisted coprecipitation process. The Fe 3 O 4 @SiO 2 @MgAl-Cl − LDH nanocomposite was characterized by FTIR, XRD, XPS, SEM, HRTEM, BET and VSM. The results showed that the Fe 3 O 4 @SiO 2 @MgAl-Cl − LDH particles possessed core (Fe 3 O 4 @SiO 2 ) shell (Cl − -LDH) structures and magnetic properties, and Cl − anions were successfully introduced into LDH interlayers. The unique intercalated structure with week interlayer interaction of Fe 3 O 4 @SiO 2 @MgAl-Cl − LDH provide efficient adsorption of methyl orange (MO), Congo red (CR) and methyl blue (MB), leading to its superior performance with much higher uptake capability with the maximum adsorption capacity of MO, CR and MB reaching 733 mg·g −1 , 910 mg·g −1 and 385 mg·g −1 , respectively. The adsorption process could be well described by pseudo-second-order model for MO, CR and MB. The experimental data of MO and CR could be fitted better with Freundlich model, while that of MB were fitted better with Langmuir model. The adsorption process was spontaneous and exothermic for MO and MB, while spontaneous and endothermic for CR. Moreover, the adsorbent exhibits excellent stability and reusability in the regeneration cycle, and a process called ‘‘post-processing step” is proposed to effectively improve the dye removal ability of the adsorbent in reuse. This study puts forward a new thought for the development of high-performance LDH adsorbents with mesoporous and Cl − intercalation structure for the efficient and rapid removal of dyes.
研究领域:
环境科学
·
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）