CATALYSIS SURVEYS FROM ASIA
·
2020
·Vol. 24
·期 2
·115-122
·
IF 2.194
Gao Meixiang,Jiang Haoxi,Zhang Minhua
This paper has systematically investigated the structures and properties of the ZrO 2 , Nano-SiO 2 and their composition. The catalysts were prepared by impregnation, characterized by N 2 adsorption–desorption, TEM, XRD, Raman, temperature-programmed desorption of NH 3 and CO 2 , FTIR spectroscopy of adsorbed pyridine and CO 2 , and UV–vis spectra. Compared with dry-mixed samples, these catalysts have larger average pore diameter, enabling ZrO 2 to be dispersed more uniformly on the surface of Nano-SiO 2 . With the Zr–O–Si bonds, ZrO 2 could interact intensely with Nano-SiO 2 . The catalyst prepared shows the best performance, with the selectivity of 93.18% and conversion of 58.52%. The preparation methods have a significant influence on the interaction between ZrO 2 and Nano-SiO 2, which then affects the acid–basic properties. This paper finds that weak acid–basic sites with moderate-intensity are more suitable for ethanol conversion to BD, with the amount of acid and basic sites as close as possible.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
SURFACE & COATINGS TECHNOLOGY
·
2024
·
IF 5.3
Bao Guo,Hongjun Kang,Xinzhi Wang,Yitong Duan,Xiaotong Li,Baiqi Gao,Zhiqiang Wang,Yang Li,Songtao Lu,Xiaohong Wu
Addressing the issue of dust deposition on photovoltaic (PV) panels is of profound scientific significance and practical value for enhancing PV power generation. Transparent superhydrophobic coating is expected to be applied in the self-cleaning of PV panels. However, developing the transparent superhydrophobic dust removal coatings remains a challenge. Herein, we developed a highly transparent F-SiO 2 coating with dual self-cleaning and dust removal functions, composed of polydimethylsiloxane (PDMS) and SiO 2 . The coating demonstrates a high transmittance of 97 %. After self-cleaning and dust removal tests, conversion efficiency of F-SiO 2 coated PV decreased by only 0.03 % and 0.01 %, respectively, demonstrating excellent self-cleaning and dust removal performance. Additionally, the F-SiO 2 exhibits high stability. Mechanism analysis of dust removal performance reveals that the decreased effective dielectric constant from the porous structure and the reduced actual contact area between the particles and the superhydrophobic surface, thereby effectively reduces the van der Waals force between dust and coating. This work provides a novel strategy to prepare self-cleaning and dust removal coatings on PV cover plate.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
高影响因子
POWDER TECHNOLOGY
·
2017
·
IF 2.942
Yanwei Hu,Ziyu Liu,Yurong He
Boiling heat transfer is widely used in energy power equipment, while the poor thermal property conventional fluids cannot meet the increase of heat transfer demand. The addition of nanoparticles into base fluids can modify the properties of base fluids and is a potential way to improve heat transfer characteristics. In present work, amorphous SiO 2 nanoparticles with an average size of 98 nm were synthesized via Stober process. And they were added into water with different mass fractions to investigate the pool boiling heat transfer characteristics. The heat transfer coefficient and critical heat flux were analyzed. Results show that the heat transfer coefficient of all fluids increases rapidly in the natural convective region but then rises gradually in the nucleate boiling region. Moreover, owing to the deposition of SiO 2 nanoparticles, the heat transfer coefficients of SiO 2 -H 2 O nanofluids are lower than that of the base fluid and reduce as the concentration increase. On the other hand, because of the wettability improvement of the heating wire surface caused by the deposition of SiO 2 nanoparticles, the critical heat fluxes of nanofluids are higher than that of the base fluid. When the concentration is 0.081%, the critical heat flux achieves a peak improvement of approximately 68.8%.
研究领域:
热力学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2019
·
IF 6.282
Tao Zhang,Yue Xu,Hongfu Li,Boming Zhang
In this study, the effect of carbon fiber (CF) surface chemistry and grafting of nano-SiO 2 on CF surface with respect to the interfacial adhesion of CF-reinforced nylon 6 composites was investigated. CFs were oxidized and reacted with poly(oxypropylene) diamines to modify the surface chemistry. The oxidized CFs were modified with 3-aminopropyltriethoxysilane and then grafted with SiO 2 nanoparticles. Fourier transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS), scanning electron microcopy (SEM), and atomic force microscopy (AFM) were used to characterize the chemistry and topographies of the CF surface. The transverse fiber bundle strength of CF oxidized and grafted nano-SiO 2 increased to 31.92 MPa and 39.35 MPa, respectively, from 12.57 MPa for untreated CF. The results indicated that the reaction between the carboxyl group and nylon 6 led to chemical bonding at the interface and it meanwhile was strengthened and toughened by uniformly distributed SiO 2 nanoparticles on the CF surface.
研究领域:
材料科学
·
复合材料
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产品关联
DOI
高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
·
2025
·
IF 3.7
Qin Liu,Yan Wang,Zhi Guo,Siyuan Wu,Wancheng Li,Chuanrun Li,Bo Wu
One of the main challenges in oil–water separation of traditional Chinese medicines (TCM) is to obtain essential oils from the aromatic water of TCM. In this study, silicon dioxide/polyvinylidene fluoride (SiO 2 /PVDF) membranes were prepared using nonsolvent induce phase separation. Then polydimethylsiloxane (PDMS) was coated to obtain PDMS/SiO 2 /PVDF membranes. Separated essential oils and water from aromatic water in the gaseous state by vapor permeation membrane separation technology. The relationship between membrane structure and membrane separation effect was investigated. Response surface methodology was used to develop a quadratic model for the separation factor, membrane permeation separation index and membrane preparation process. The optimal process parameters for the membrane separation were 12.31% (mass) concentration of PVDF solution, 9.6% (mass) of N,N -dimethylacetamide in the solidification bath, and 0.2 g hydrophobic nano-SiO 2 incorporation, with a separation factor of 14.45, and a membrane flux of 1203.04 g·m –2 ·h –1 . Compared with the PDMS/PVDF membranes, the separation factor and membrane flux were increased by 68.59% and 3.46%, respectively. Compared with the SiO 2 /PVDF membranes, the separation factor and membrane flux were increased by 478% and 79.33%, respectively. Effectively mitigated the limitations of traditional polymer membrane material performance affected by the “trade-off” effect. Attenuated total internal reflection-Fourier transform infrared spectroscopy, contact angle, scanning electron microscopy and energy dispersive spectroscopy were used to characterize the PDMS/SiO 2 /PVDF membranes, and gas chromatography was used to characterize the permeate. In addition, the contents of L -menthol, L -menthone, menthyl acetate and limonene in the permeate, conformed to the European Pharmacopoeia standards . This study provided an effective preparation strategy of a feasible hydrophobic powder polymer membrane for the separation of essential oils from gaseous peppermint aromatic water.
研究领域:
材料科学
·
中药学
·
分离技术
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Jiaochun Zheng,Mao Deng,Junjing Duan,Jianqi Qi,Zhangyi Huang,Haomin Wang
The nanocrystalline 0.35SiO 2 -0.65ZrO 2 (65 mol% monoclinic ZrO 2 ) glass-ceramic was successfully fabricated via a high-pressure cold sintering process (CSP), displaying remarkable nano hardness and elastic modulus of 12.5 and 154.8 GPa, respectively. We conducted a thorough investigation of the influence of NaOH solution concentration, liquid-to-solid mass ratio, sintering temperature , and pressure on the phase compositions, microstructural evolution , and densification. Notably, excessive NaOH concentration (>0.7 M) results in the transformation of SiO 2 from an amorphous phase to α-quartz, hindering densification. However, below 0.7 M, increasing NaOH concentration enhances the densification processes. Furthermore, higher temperature and pressure contribute to improved densification. It is worth mentioning that there is no grain growth for the ZrO 2 phases during the CSP, indicating that the densification of the nanocrystalline 0.35SiO 2 -0.65ZrO 2 glass-ceramic is primarily governed by the glass phase.
研究领域:
材料科学
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纳米技术
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产品关联
DOI
高影响因子
RSC Advances
·
2024
·Vol. 14
·期 7
·4518-4532
·
IF 3.9
Dazheng Ci,Ning Wang,Yunqi Xu,Shanshan Wu,Jing Wang,Haoran Li,Shouhu Xuan,Qunling Fang
Wastewater discharged from industrial, agricultural and livestock production contains a large number of harmful bacteria and organic pollutants, which usually cause serious harm to human health. Therefore, it is urgent to find a “one-stone-two-birds” strategy with good antimicrobial and pollutant degradation activity for treating waste water. In this paper, SiO2@AuAg/Polydopamine (SiO2@AuAg/PDA) core/shell nanospheres, which possessed synergistic “Ag+-release–photothermal” antibacterial and catalytic behaviors, have been successfully prepared via a simple in situ redox polymerization method. The SiO2@AuAg/PDA nanospheres showed good catalytic activity in reducing 4-nitrophenol to 4-aminophenol (0.576 min−1 mg−1). Since the AuAg nanoclusters contain both gold and silver elements, they provided a high photothermal conversion efficiency (48.1%). Under NIR irradiation (808 nm, 2.5 W−2), the catalytic kinetics were improved by 2.2 times. Besides the intrinsic Ag+-release, the photothermal behavior originating from the AuAg bimetallic nanoclusters and the PDA component of SiO2@AuAg/PDA also critically improved the antibacterial performance. Both E. coli and S. aureus could be basically killed by SiO2@AuAg/PDA nanospheres at a concentration of 90 μg mL−1 under NIR irradiation. This “Ag+-release–photothermal” coupled sterilization offers a straightforward and effective approach to antimicrobial therapy, and further exhibits high potential in nanomedicine for combating bacterial contamination in environmental treatment and biological fields.
研究领域:
环境科学
·
纳米医学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2020
·
IF 6.306
Long Wu,Weimin Zhang,Chen Liu,Mohamed F. Foda,Yongheng Zhu
In this work, based on the strawberry-like SiO 2 /Ag nanocomposites (SANC) immersed filter paper, a newly surface-enhanced Raman scattering (SERS) substrate was constructed for the detection of acrylamide (AAm) in food products. To construct filter paper-based SANC (F-SANC) SERS substrates, SiO 2 nanoparticles (SNP) were firstly synthesized and acted as carriers. After that, the in-situ preparation of silver nanoparticles (Ag NP) on SNP surface was carried out to form the strawberry-like three-dimensional (3D) structure of SANC. Finally, SANC were entangled into the filter paper to produce nanoarchitecture, thus providing enhanced plasmon resonance between SANC with strong SERS signal. Under the optimized conditions, the method exhibited good performance toward AAm with a vast linear response from 0.1 nM to 50 μM (R = 0.9935), limit of detection (LOD) of 0.02 nM (S/N = 3), and the recoveries of 80.5%~105.6% for practical samples. This strategy showed good robustness in the rapid and sensitive detection of AAm, which could be a promising strategy in food analysis and verification.
研究领域:
食品科学
·
分析化学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NUCLEAR MATERIALS
·
2020
·
IF 2.485
Guilin Wei,Xiaoyan Shu,Zhentao Zhang,Fen Luo,Yi Liu,Bingsheng Li,Yi Xie,Lan Wang,Xirui Lu
The treatment of radioactive iodine waste is particularly difficult because of its volatilization issues. In this study, amorphous silica gel was used to gradually replace crystalline SiO 2 in B 2 O 3 -Bi 2 O 3 -ZnO-SiO 2 based materials aimed to investigate the effects on iodine waste immobilization. Samples with different silica gel replacements (0, 20, 40, 60, 80, and 100%) were characterized by XRD, FT-IR, and SEM-EDS. The results showed that silica gel had a benefit in the immobilization of iodine waste at low-sintering temperatures (500, 550, and 600 °C). At 550 °C, AgI was immobilized in the pure glassy matrix and elements (Ag and I) distributed uniformly on the matrix surface. FT-IR analysis presented the tetrahedral SiO 4 units in the sintered samples that were mainly in the form of sheets. Our work revealed the potential application of silica gel in the field of iodine waste immobilization.
研究领域:
核废料管理
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2019
·Vol. 9
·期 53
·30790-30796
·
IF 3.049
Haoyang Zou,Lan Wang,Huaizhi Tao,Yi Liu,Meiqi Chang,Shiyu Yao
Recently, polyacrylamide (PAM) has been widely used in polymer flooding technology to enhance oil recovery and oil production. However, the difficulty in removing hydrolysed PAM (HPAM) from wastewater still seriously blocks the further application of polymer flooding in the oilfields. Herein, we demonstrate the preparation of SiO2@TiO2:Eu3+@TiO2 core double-shell microspheres (STT) through a two-step solvothermal and sol–gel coating strategy. The as-prepared STT exhibits an ideal photocatalytic activity for the photodegradation of HPAM. More importantly, by using STT as the model, the correlation between fluorescence intensity and photocatalytic activity of the photocatalysts is investigated. The results suggest their oppositional relationship. Since many kinds of photocatalysts are utilized in the degradation of organic pollutants, it is believed that our work will not only promote the development of photocatalysis in the field of oil extraction, but also offer a convenient method for evaluating the photocatalytic activity of the photocatalysts.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2013
·Vol. 15
·期 6
·1-9
·
IF 2.175
Xu Yaohui,Zhou Yang,Ma Wenhui,Wang Shixing,Li Shaoyuan
Abstract The Fe 3 O 4 nanoparticles [NPs] coated with silica nanoparticles were designed and prepared, the obtained Fe 3 O 4 @SiO 2 NPs have uniform spherical morphology with a mean diameter of about 22 nm. The inert silica coating on the surface of Fe 3 O 4 NPs not only significantly prevented their aggregation in solution but also improved their chemical stability and provided wider sites for surface modification with organic chemosensors. Subsequently an attempt had been made that the as-synthesized Fe 3 O 4 @SiO 2 NPs were modified by N -(rhodamine-6G) lactam–ethylenediamine, the functionalized magnetic Fe 3 O 4 @SiO 2 NPs (Fe 3 O 4 @SiO 2 -Rho) served as a “naked eye” fluorescent sensor to detect Hg 2+ . The Fe 3 O 4 @SiO 2 -Rho NPs exhibited selective “turn-on” type fluorescent change from colorless to orange when adding to Hg 2+ . In addition, the adsorption experiments revealed that the Fe 3 O 4 @SiO 2 -Rho NPs had effective removal toward Hg 2+ . Moreover, the functionalized Fe 3 O 4 @SiO 2 microspheres displayed superparamagnetic properties, which made it easier to separate the nanocomposites from the liquid phase by adding an external magnetic field. Our efforts provided a potential magnetic nanomaterial for sensitive detection and removal toward Hg 2+ simultaneously. Graphical Abstract A rhodamine 6G derivative functionalized Fe 3 O 4 @SiO 2 nanoparticles were designed and synthesized (as Fe 3 O 4 @SiO 2 -Rho). The Fe 3 O 4 @SiO 2 -Rho exhibited selective “turn-on” type fluorescent change from colorless to orange with Hg 2+ , which constituted an Hg 2+ -selective fluorescent colorimetric nanosensor.
研究领域:
材料科学
·
环境化学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2019
·
IF 4.046
Kai Luo,Jun Li,Qing Han,Zhongyuan Lu,Xin Deng,Li Hou,Yunhui Niu,Jun Jiang,Xiaoying Xu,Pan Cai
As an ideal cementitious material for the maintenance of historic buildings and the replacement of interior decoration mortars, the widespread application of natural hydraulic lime (NHL) is expected to play an important role in CO 2 capture and utilization. Structures and properties of NHL2 mortars with nano-SiO 2 (NS) under carbonation were researched in this paper. NHL mortars could capture CO 2 during hardening process of air-hardening contents, and the captured CO 2 would be fixed in the matrix to form CaCO 3 . Carbonation percentage and extent of NHL2 mortars increased by the addition of NS whatever in atmospheric or accelerated carbonation condition. Much more compacted carbonation surfaces than that of the uncarbonated region for NHL2 mortars with NS was observed. The addition of NS will reduce the porosity and big pores (approximately 1 μm) while increase the mesopores (approximately 50 nm) of the mortars. Carbonation reaction of NHL2 mortars seemed to be improved by the addition of NS, which would be beneficial to the collection, solidification and further utilization of CO 2 .
研究领域:
建筑材料学
·
环境科学
·
土木工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）