ACS Omega
·
2021
·
IF 3.512
Yi Qin,Shudong Zhang,Shuai Han,Tingting Xu,Cui Liu,Min Xi,Xinling Yu,Nian Li,Zhenyang Wang
Cycloaliphatic epoxy (CE) resin plays a vital role in insulation equipment due to its excellent insulation and processability. However, the insufficient ability of CE to confine electrons under high voltage often leads to an electric breakdown, which limits its wide applications in high-voltage insulation equipment. In this work, the interface effect of inorganic nano-SiO2 introduces deep traps to capture electrons, which is synergistic with the inherent ability of the voltage stabilizer m-aminobenzoic acid (m-ABA) to capture high-energy electrons through collision. Therefore, the insulation failure rate is reduced owing to doping of the functionalized nanoparticles of the m-ABA-grafted nano-SiO2 (m-ABA-SiO2) into the CE. It is worth noting that the breakdown field strength of this m-ABA-SiO2/CE reaches 53 kV/mm, which is 40.8% higher than that of pure CE. In addition, the tensile strength and volume resistivity of m-ABA-SiO2/CE are increased by 29.1 and 140%, respectively. Meanwhile, the glass transition temperature was increased by about 25 °C and reached 213 °C. This work proves that the comprehensive performance of CE-based nanocomposites is effectively improved by m-ABA-SiO2 nanoparticles, showing great application potential in high-voltage insulated power equipment.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF INORGANIC BIOCHEMISTRY
·
2018
·
IF 3.063
Min Wang,Xiaofang Fei,Shaowu Lv,Ye Sheng,Haifeng Zou,Yanhua Song,Fei Yan,Qianlong Zhu,Keyan Zheng
In this study, we designed and synthesized two novel fluorescent magnetic nanoparticles . Fe 3 O 4 @SiO 2 -NH-GSH-CdTe (FSGC) (GSH = glutathione) nanoparticles were synthesized using amino-functionalized Fe 3 O 4 @SiO 2 nanoparticles and GSH-stabilized CdTe quantum dots (CdTe QDs), while flexible Fe 3 O 4 @SiO 2 -NH-GSH-CdTe-NH-NH 2 (FSGCN) nanoparticles were synthesized using the FSGC precursor and 1,6-hexamethylenediamine. These two kinds of nanoprobes exhibited excellent magnetic and fluorescent properties. By comparing the fluorescence quenching effect of folic acid (FA) on FSGC and FSGCN, we found that the quenching effect of FA on FSGC was acute and the process was too fast to determine the FA content. However, the quenching effect of FA on flexible FSGCN was mild and hence it could be used as a nanoprobe to determine FA concentration. At physiological pH, the fluorescence quenching effect of FA on the FSGCN nanoprobes was fitted according to the Stern–Volmer equation with a linear response in the concentration range of 0.14 to 4.20 μg mL −1 with a detection limit of 15.1 × 10 −9 g mL −1 (S/N = 3) under optimized experimental conditions. The proposed flexible nanoprobe was successfully used to determine the content of FA in folic acid tablets. Recovery was found to be in the range of 92.7%–105.6% with a relative standard deviation of 1.12%–3.84%. Owing to their good stability, environment-friendly characteristics, high selectivity, and good optical properties and biocompatibility, these nanoprobes have potential for usage in practical applications.
研究领域:
生物医学工程
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
·
2016
·
IF 5.267
Peng Tan,Yan-Hua Li,Xiao-Qin Liu,Yao Jiang,Lin-Bing Sun
Silver (Ag)-based nanoparticles are one type of highly effective antimicrobial widely used in medical devices, consumer products, and wound dressing. Although Ag(I) rather than Ag(0) is the active species in antibacterial processes, the use of Ag(I) as antibacterial materials is hindered by its instability toward light irradiation. In this paper, we report the fabrication of core–shell AgCl@SiO2 nanoparticles, which comprise a core of AgCl nanoparticles and a shell of porous silica, for antibacterial applications for the first time. The porous silica shells not only enhance the stability of AgCl by preventing the core from direct light irradiation but also allow active Ag(I) to pass through continuously to inhibit the growth of bacteria. It is worth noting that the synthesis is achieved by a facile one-pot method in which the surfactant hexadecyltrimethylammonium chloride used for the formation of AgCl nanoparticles also acts as a structure-directing agent in the subsequent creation of porous silica. Our results show that the obtained AgCl@SiO2 nanoparticles exhibit well-defined core–shell structure and are highly efficient in the growth inhibition of Escherichia coli. More importantly, the stability of Ag(I) toward light irradiation is greatly enhanced by the protection of the silica shell. The convenient fabrication, well-defined core–shell structure, and enhanced stability make AgCl@SiO2 nanoparticles highly promising for antibacterial applications.
研究领域:
材料科学
·
微生物学
·
医学
✓ 已验证
产品关联
DOI
高影响因子
THERMOCHIMICA ACTA
·
2021
·
IF 3.115
Lei Liu,Xiang Cheng,Xiwang Miao,Ying Zhang,Min Guo,Fangqin Cheng,Mei Zhang
In this work, a series of SiO 2 @n-octadecane capsules were prepared by one step emulsion polymerization, the influence of emulsifying speed, ammonia and TEOS contents, reaction temperature, concentration of emulsifier and the amount of PVP on the size, structure and performance was detailed investigated. It can be seen from SEM characterization that among these factors emulsification speed had the greatest influence on capsule size, while followed by the ammonia and TEOS content. According to TEM results, the ammonia and TEOS contents were the most important factors on the structure (shell thickness and surface smoothness) of the capsules, attributing to ammonia and TEOS were the catalyst and reactant of hydrolysis polymerization, respectively. Generally, the crystallinity of the samples became worse as the size decreased. DSC results showed that excessive ammonia or TEOS caused a significant drop in the enthalpy of the samples, furthermore, the enthalpy basically decreased with the attenuation of the inner radius of the sample. The target SiO 2 @n-octadecane capsule was sample C2 with high enthalpy (127.7 J/g), size of 1.62 μm, shell thickness of 68 nm, and smooth surface. More importantly, within the parameters studied, a series of SiO 2 @n-octadecane capsules were successfully synthesized with different enthalpy values (min 85.9 J/g, max 144.3 J/g), sizes ranging from 0.63–2.75 μm, shell thickness 32–79 nm and different smooth surfaces. Therefore, the controllable synthesis of SiO 2 @n-octadecane capsules within the above range can be achieved by simulating different parameters and their development.
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
APPLIED CATALYSIS A-GENERAL
·
2022
·
IF 5.723
Yue Li,Huan Ren,Daolai Sun,Xinqiang Zhao,Satoshi Sato
Liquid-phase catalytic hydrodeoxygenation of 1,2-decanediol (1,2-DDO) to form 1-decanol was performed over various non-noble metal-loaded acidic catalysts, and Cu loaded on amorphous SiO 2 -Al 2 O 3 exhibited a high catalytic activity for the formation of 1-decanol. A high 1-decanol selectivity of 84.7% with a complete 1,2-DDO conversion was obtained within only 15 min over the Cu/SiO 2 -Al 2 O 3 at 250 °C under 10 MPa H 2 pressure. The temperature at 250 °C and the H 2 pressure higher than 3 MPa were conducive to the efficient production of 1-decanol from 1,2-DDO. In contrast to the previously reported noble metal catalysts, Cu/SiO 2 -Al 2 O 3 required a relatively high reaction temperature, while an extremely high 1-decanol productivity of 78 mmol g cat −1 h −1 could be achieved. Meanwhile, the hydrodeoxygenation of 1,2-decanediol over Cu/SiO 2 -Al 2 O 3 proceeded via a reaction mechanism in which decanal was formed as the intermediate. In addition, the Cu/SiO 2 -Al 2 O 3 catalyst was reusable at least five times without serious deactivation.
研究领域:
催化化学
·
能源化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2022
·Vol. 33
·期 33
·25383-25391
·
IF 2.779
Zhang Cong,Liu Xiansong,Kan Xucai,Feng Shuangjiu,Zhu Yong,Yang Yujie,Zhang Zongyang
Soft magnetic composites serve in electrical applications and sustainable energy supply, the magnetic flux changes in response to changes of the applied magnetic field, with energy loss. To reduce the loss, in this paper, the soft magnetic composite Fe 50 Ni 50 powder coated with nano-SiO 2 was prepared by tetraethoxysilane sol–gel method, and the microstructure of the coating was characterized. Then, soft magnetic Fe 50 Ni 50 powder cores have been prepared, and annealed with different atmospheres. The power loss is lower when the magnetic cores were annealed in a reducing hydrogen atmosphere. The lowest power loss (1390.7 mW/cm 3 , f = 1000 kHz, B = 50 mT, 120 °C) was obtained when the cores annealed at 730 °C in H 2 atmosphere. The results show that the eddy current loss is significantly reduced by coating SiO 2 , and the power loss is reduced about 33% in high-frequency (1 MHz and 50 mT, 25 °C). From 25 to 120 °C, the power loss at 1 MHz decreases by about 33% due to the reduction of hysteresis loss and eddy current loss. The excellent properties are very applicable for the inductors of 5G technology.
研究领域:
材料科学
·
电气工程
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Environmental Science and Technology
·
2020
·Vol. 17
·期 9
·4061-4074
·
IF 2.54
Liu H.,Li D.,Shao L.,Wu D.,Zhang H.,Yuan J.,Xu F.
In this study, a crack-free PDMS–SiO 2 –BiPO 4 (P/Si/Bi) composite was prepared via a solgel-assisted route by dispersing pre-prepared bismuth oxybromide into a solution that was composed of hydroxyl-terminated polydimethylsiloxane (PDMS–OH), tetraethyl orthosilicate and phosphoric acid. Analysis via the FTIR, XRD, XPS and SEM–EDX techniques demonstrated that the nonisolated BiPO 4 particles with a monoclinic crystal phase were uniformly distributed on the surface of the P/Si/Bi composite, which can provide more active sites and a larger surface area for photocatalysis compared with other materials. The photocatalytic activity of the P/Si/Bi composite loaded with various mass ratios of BiPO 4 (9 wt%, 12 wt%, 18 wt% and 27 wt%) was investigated via the degradation of methylene blue (MB, 10 mg/L) under UV light irradiation. It was found that the P/Si/Bi composite loaded with 18 wt% BiPO 4 realized the highest degradation efficiency of MB, and its corresponding apparent rate constant was approximately 2.2 times that of the PDMS–SiO 2 –TiO 2 composite (loaded with 18 wt% TiO 2 ). The effects of inorganic ions on the degradation of MB were also investigated. The static contact angle and photocatalytic activity of the P/Si/Bi composite changed minimally after five cyclic experiments, thereby demonstrating its remarkable durability in sustainable applications. In addition, the photogenerated reactive species that were responsible for the degradation of MB within the P/Si/Bi composite were identified, and a photocatalytic mechanism was proposed.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
JOM
·
2015
·Vol. 68
·期 9
·2371-2380
·
IF 1.757
Lai Huixian,Huang Liuqing,Lu Chenghao,Fang Ming,Ma Wenhui,Xing Pengfei,Li Jintang,Luo Xuetao
Boron removal from metallurgical-grade silicon by Li 2 O-SiO 2 slag refining under an air atmosphere was experimentally investigated to explore the potential of this method for achieving high boron removal. The boron concentration in the refined silicon was studied under different conditions of holding time, slag composition, and mass ratio of slag to silicon. The boron concentration in metallurgical-grade silicon was successfully reduced from 8.6 ppmw to 0.4 ppmw after slag refining for 0.5 h at 1973 K when the mass ratio of the 60 wt.% Li 2 O-40 wt.% SiO 2 slag to metallurgical-grade silicon was 3. It was proposed that the addition of CaF 2 decreased the activity of silica, which brings about a negative effect on the boron removal capacity of Li 2 O-SiO 2 slags. Moreover, the reaction mechanism and kinetics of boron removal were further studied. Analysis of the boron concentration in the resulting slag after refining revealed that the primary boron removal approach was that a large amount of boron was oxidized and then volatilized to the atmosphere in the form of gaseous borates. Based on the two-film theory, the total mass transfer coefficient of boron was determined to be 2.3 × 10 −2 μ m/s.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
KOREAN JOURNAL OF CHEMICAL ENGINEERING
·
2020
·Vol. 37
·期 4
·623-632
·
IF 2.69
Yan Zhinan,Kang Yong,Li Dan,Liu Yu Chun
Hematite (α-Fe 2 O 3 ) is a promising alternative to the catalysts currently used due to its low cost, fairly good activity and environmentally friendly properties. In this study, α-Fe 2 O 3 /SiO 2 nanocatalysts promoted with cobalt and cerium (Co 3 O 4 -CeO 2 -α-Fe 2 O 3 /SiO 2 ) were prepared via wet co-impregnation method, and the effects of promoters on catalytic performances for SO 2 oxidation at different temperatures, SO 2 concentrations, cycle numbers, catalytic stability as well as catalyst charging were investigated. The results indicated that SO 2 conversion rose with the increasing of catalyst charging and SO 2 concentration. Also, the as-prepared catalyst had the maximum SO 2 conversion at the reaction temperature of 500 °C, excellent catalytic recyclability and activity stability. Its physicochemical and redox properties were characterized by XRD, BET, SEM, FT-IR and XPS. The results of XRD and FT-IR spectra confirmed that the formation of Ce 2 FeO 4 network in the Co-Ce co-doped catalysts proved the promoting effect of cerium on higher valence state of the active ingredient. The N2 adsorption/desorption results evidenced that cerium could increase the proportion of mesoporous, and the XPS spectra indicated that cobalt and cerium in the catalysts could increase the available oxygen (O β /O α ) for the redox reaction. Due to its excellent low onset temperature, fairly good activity and environmentally friendly properties, the as-prepared catalyst of Co 3 O 4 -CeO 2 -α-Fe 2 O 3 /SiO 2 appeared to be more efficient for the SO 2 conversion in a large concentration range.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
ENERGY & FUELS
·
2020
·
IF 3.421
Han Jia,Jiajun Dai,Pan Huang,Yugui Han,Qiuxia Wang,Juan He,Jinyong Song,Xin Wei,Hui Yan,Dexin Liu
It is greatly desired to develop a high-efficiency demulsifier for the treatment of O/W emulsions in the production fluids of the petroleum industry. In this study, the amphiphilic Janus-SiO2 nanoparticles (Janus-C18) was synthesized and used as a demulsifier for surfactant-stabilized O/W emulsions. The successful preparation of Janus-C18 was verified by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and contact angle measurements. Then, Janus-C18’s demulsification efficiency was systematically evaluated by the bottle test. Various silica nanoparticles and emulsifier were employed in the control experiments. Based on the Janus-C18’s demulsification performance in different conditions and the ζ-potential measurement, the possible demulsification mechanism of Janus-C18 was proposed. Furthermore, Janus-C18 exhibited excellent performance in separating oil from crude oil/water emulsions at a relatively low concentration (150 mg/L), with the oil removal rate exceeding 99%.
研究领域:
化学工程
·
材料科学
·
石油工程
✓ 已验证
产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2019
·
IF 4.046
Yamei Cai,Dongxing Xuan,Chi Sun Poon
Swelling caused by alkali-silica reaction (ASR) in concrete is a deleterious behavior due to reactions between alkaline pore solution and amorphous or metastable forms of silica in aggregates. Generally, mitigation by using pozzolanic materials is commonly adopted. This study compared the effectiveness of a highly-reactive nano-SiO 2 (NS) and a slowly-reactive waste glass powder (WGP) on mitigating ASR of cement mortars prepared with crushed glass cullet as aggregates. The experimental results showed that incorporating 2% NS or 10% WGP or a hybrid of the two in the mortar can decrease the ASR expansion. Using WGP resulted in larger reduction in the ASR expansion than using NS. Meanwhile, there was an improvement of strength from 7 d to 28 d for the mortar prepared with WGP. The composition of reaction products containing the ASR gel formed in a simulated ASR condition and the macro-/micro-structure of the tested mortars were further analyzed. It was found that the reaction products formed with high ratios of Na/Si and Ca/Si were favorable in mitigating the ASR expansion. For the specimen prepared with WGP, the increase in the ratio of Ca/Si would increase the stiffness of the ASR gel, and a higher Na/Si ratio would help reduce the osmotic pressure. The findings from this study would be useful for the selection of pozzolans to mitigate the ASR effect when using crushed glass cullet as aggregates in cement mortars.
研究领域:
材料科学
·
土木工程
✓ 已验证
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2017
·Vol. 82
·期 2
·424-431
·
IF 1.575
Zhang Jing,Liu Mao,Liu Zhijie,Yang Tao,He Qiulai,Yang Kai,Wang Hongyu
Abstract This paper presents the synthesis of a novel core–shell covalently functionalized Fe 3 O 4 coated SiO 2 decorated graphene oxides (Fe 3 O 4 @SiO 2 –GO) adsorbent. The prepared Fe 3 O 4 @SiO 2 –GO was characterized by fourier transform infrared spectrum, X-ray diffraction(XRD), X-ray photoelectron spectroscopy (XPS), and magnetic measurements. And the adsorption properties of the Fe 3 O 4 @SiO 2 –GO toward malachite green were systematically investigated. Various factors possibly affecting the adsorption behavior (initial concentration, contact time, and adsorbent dosage) were also studied in detail. The adsorption capacity (q m ) of Fe 3 O 4 @SiO 2 –GO for malachite green was found to be 265.87 mg/g with best fit to Langmuir isotherm ( R
2 = 0.968), and the adsorption mechanism follows the pseudo-second-order model ( R
2 = 0.981). The results indicate that the Fe 3 O 4 @SiO 2 –GO adsorbent, which is easily separated via an external magnetic field, is a potential low-cost effective material for malachite green removal from contaminated water. Graphical Abstract
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）