CONSTRUCTION AND BUILDING MATERIALS
·
2020
·
IF 4.419
Zhenhai Xu,Jianming Gao,Zonghui Zhou,Yasong Zhao,Xuemei Chen
In order to clarify the enhancing mechanism of nano-TiO 2 (NT) on tricalcium silicate (C 3 S) paste, the hydration and microstructure of C 3 S with and without NT were investigated. Hydration properties were analyzed by setting time, compressive strength , hydration heat, Ca(OH) 2 content and relative content of C-S-H. Moreover, the microstructure of C 3 S paste was studied by pore structure and micromorphology. The results showed that seeding effect of NT promoted the chemical activity as well as hydration of C 3 S and more NT led to higher hydration degree. Besides, NT can increase the content of Ca(OH) 2 and the relative content of C-S-H, which also proved the enhancement effect of NT on C 3 S chemical activity and hydration. Furthermore, the seeding effect and filling effect of NT decreased total porosity, enhanced density and meliorated the microstructure of hardened C 3 S paste. Ultimately, the improved hydration and optimized microstructure introduced by NT enhanced the compressive strength of C 3 S paste.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
ACS Omega
·
2024
·
IF 3.7
Xiaoru Hao,Zhihao Cheng,Yu Zhang,Jun Xie,Haikun Zheng,Chunxiao Yue,Wei Sheng
The operation of aerospace equipment is often affected by icing and frosting. In order to reduce the loss caused by icing in the industrial field, it is an effective method to prepare superhydrophobic coatings by modifying nanoparticles with low surface energy materials. In order to explore a method of preparing a superhydrophobic surface that can be popularized, a two-step spraying method was employed to create a superhydrophobic coating. The surface was characterized by Fourier transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (SEM). The optimal preparation process was obtained by analyzing the surface contact angle data. The results showed that stearic acid was grafted onto the surface of TiO2 by esterification reaction. The existence of long methyl and methylene hydrophobic groups in the tail of the stearic acid molecule made the modified TiO2 hydrophobic. It is verified that water molecules have strong adsorption on the surface of unmodified TiO2. Stearic acid molecules can reduce the interfacial energy in the system.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CLAY SCIENCE
·
2017
·
IF 3.101
Sen Lin,Shiyong Sun,Kexuan Shen,Daoyong Tan,Hongping Zhang,Faqin Dong,Xiaoxin Fu
Photocatalytic microcompartments have attracted increasing interests in the field of photocatalytic degradation . This work focused on the construction and characterization of a novel photocatalytic microsystem comprising polydopamine-modified TiO 2 nanoparticles (NPs) dispersed in clay-based colloidosomes, utilizing partially hydrophobic montmorillonite particles as building blocks for colloidosome membrane assembly. Assessment of photocatalytic activity was performed by photocatalytic degradation of methylene blue and rhodamine B, with the small molecule dyes decomposing within the compartmentalized microsystems. Encapsulation of TiO 2 NPs within the clay colloidosomes enhanced the efficiency of photocatalytic degradation. The results showed a selective degradation of methylene blue in the presence of rhodamine B, with associated λ MB /λ RhB of 2.04. The present study indicates that photocatalytic semiconductor NPs encapsulated in clay colloidosomes form a promising microsystem with great potential for application in environmental remediation.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2012
·Vol. 126
·期 2
·697-705
·
IF 1.289
Tursun Abdiryim,Aminam Ubul,Ruxangul Jamal,Yuchuan Tian,Tunsagul Awut,Ismayil Nurulla
Polyaniline/nano-TiO 2 composites with the content of nano-TiO 2 varying from 6.2 wt % to 24.1 wt % were prepared by using solid-state synthesis method at room temperature. The structure and morphology of the composites were characterized by the Fourier transform infrared (FTIR) spectra, ultraviolet-visible (UV–vis) absorption spectra, X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The electrochemical performances of the composites were investigated by galvanostatic charge–discharge measurement, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The results from FTIR and UV–vis spectra showed that the composites displayed higher oxidation and doping degree than pure PANI. The XRD and morphological studies revealed that the inclusion of nano-TiO 2 particles hampered the crystallization of PANI chains in composites, and the composites exhibited mixed particles from free PANI particles and the nano-TiO 2 entrapped PANI particles. The galvanostatic charge–discharge measurements indicated that the PANI/nano-TiO 2 composites had higher specific capacitances than PANI. The composite with 6.2 wt % TiO 2 had the highest specific capacitance among the composites. The further electrochemical tests on the composite electrode with 6.2 wt % TiO 2 showed that the composite displayed an ideal capacitive behavior and good rate ability. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2017
·
IF 5.951
Binbin Jin,Guodong Yao,Xiaoguang Wang,Kefan Ding,Fangming Jin
Formic acid, as an excellent hydrogen-storage material, has recently become increasingly important. Previous conversion of biomass into formic acid suffers from problems of strict operation conditions such as the use of a high concentration of H2O2 oxidant and alkali at higher temperatures or the precious metal catalysts. Here, a straightforward photocatalytic method to selectively convert glucose into formate is first reported. Using a nano TiO2 catalyst, we show that glucose can be efficiently converted into formic acid with a high yield of 35% at ambient condition with 0.03 M NaOH concentration, and the proposed method also worked on xylose for formate production. The conversion of glucose into formic acid is mainly attributed to the accelerated formation of active oxidative radicals (O2•–, •OH) in the presence of hydroxyl ions, and also, hydroxyl ions adjust the charge of the TiO2 surface and control the adsorption of glucose and the desorption of formic acid. These results open up a new approach toward economical utilization of sustainable biomass and clean solar energy for formic acid production.
研究领域:
催化化学
·
可再生能源
·
材料科学
·
环境化学
·
绿色化学
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2015
·
IF 2.719
Xi Li,Jie Li,Yingchun Li,Kai Xia
8-hydroxyquinoline aluminum/nano-TiO 2 composites were prepared via in situ. In order to make a better combination of the two component, Octavinyl-T8-silsesquioxane (8-vinyl POSS) was introduced into the composite system . The structure and properties of the samples were characterized by XRD , SEM, XPS , UV–visible absorption, Fluorescence spectra and Time-resolved emission-decay. These results show both β-phase and γ-phase of Alq 3 exist in the composite products. Meanwhile, the addition of nano-TiO 2 and 8-vinyl POSS does not change the crystalline and structure of as-prepared Alq 3 . Interestingly, however, XPS spectra shows that two new kinds of interaction forces emerge after the addition of 8-vinyl POSS, owing to the formation of Al–O–Si and Si–O–Ti bond, presumably. Besides, the emission intensity of Alq 3 /nano-TiO 2 and Alq 3 /8-vinyl POSS/nano-TiO 2 increases by 22% and 33%, respectively. The addition of TiO 2 and 8-vinly POSS will not affect the position of emission peak, but will increase the transmission efficiency in electron–hole pairs. In the meantime, surprisingly, the modified Alq 3 has a longer lifetime than as-prepared Alq 3 .
✓ 已验证
产品关联
DOI
高影响因子
Frontiers of Environmental Science & Engineering
·
2020
·Vol. 14
·期 6
·1-12
·
IF 4.053
Zhang Yingdan,Liu Na,Wang Wei,Sun Jianteng,Zhu Lizhong
Titanium dioxide nanoparticle (nano-TiO 2 ), as an excellent UV absorbent and photo-catalyst, has been widely applied in modern industry, thus inevitably discharged into environment. We proposed that nano-TiO 2 in soil can promote crop yield through photosynthetic and metabolic disturbance, therefore, we investigated the effects of nano-TiO 2 exposure on related physiologic-biochemical properties of rice ( Oryza sativa L.). Results showed that rice biomass was increased >30% at every applied dosage (0.1–100 mg/L) of nano-TiO 2 . The actual photosynthetic rate (Y(II)) significantly increased by 10.0% and 17.2% in the treatments of 10 and 100 mg/L respectively, indicating an increased energy production from photosynthesis. Besides, non-photochemical quenching (Y(NPQ)) significantly decreased by 19.8%–26.0% of the control in all treatments respectively, representing a decline in heat dissipation. Detailed metabolism fingerprinting further revealed that a fortified transformation of monosaccharides (D-fructose, D-galactose, and D-talose) to disaccharides (D-cellobiose, and D-lactose) was accompanied with a weakened citric acid cycle, confirming the decrease of energy consumption in metabolism. All these results elucidated that nano-TiO 2 promoted rice growth through the upregulation of energy storage in photosynthesis and the downregulation of energy consumption in metabolism. This study provides a mechanistic understanding of the stress-response hormesis of rice after exposure to nano-TiO 2 , and provides worthy information on the potential application and risk of nanomaterials in agricultural production.
研究领域:
农业科学
·
植物生理学
·
环境科学
·
纳米技术
✓ 已验证
DOI
高影响因子
FLOW TURBULENCE AND COMBUSTION
·
2023
·Vol. 111
·期 2
·697-715
·
IF 2.4
Luo Junxiao,Shi Weidong,Chen Liang,Fang Guofeng,Zhang Liang
Nanofluids have become more and more attractive to the modern industry due to their high performance in heat transfer and combustion. As one of the key influencing factors, the atomization mechanism of nanofluids induced by airflow is more complex than that of pure liquids, which has attracted great attention recently. In this study, the spray characteristics of TiO 2 –propylene glycol nanofluids were investigated by focusing on the effects of nano-TiO 2 additives on atomization. On the basis of high-speed shadow imaging, the spray morphology of the base fluid injected from an air atomizing nozzle under different pressures was analyzed first. Then a laser particle size analyzer was used to obtain the droplet size distribution of the nanofluids. The air pressure at the inlet of the atomizer was found to have more contribution to the atomization of nanofluids. And when the air pressure exceeded 0.35 MPa, the Sauter mean diameter (D 32 ) of the base fluid droplets was insensitive to the change of air pressure. Subsequently, the contribution of nanoparticles to atomization was discussed. An empirical correlation was proposed between the Sauter mean diameter (D 32 ) and the dimensionless parameters such as the gas Weber number (We g ), liquid–gas momentum ratio (q), and the volume fraction of nano-TiO 2 , etc. Results indicated that adding nanoparticles enhanced the jet stability by increasing the viscosity at a low jet velocity, while the jet instability was increased due to the nanoparticles promoting the cavitation at a high jet velocity.
研究领域:
热能工程
·
机械工程
·
流体力学
·
材料科学
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2023
·
IF 7.4
Jihong Jiang,Yanchun Miao,Han Wang,Xiaobin Dong,Yali Li,Junlin Lin,Zeyu Lu
Regardless of how good pre-dispersion of nano-TiO 2 in aqueous solutions, re-aggregation rapidly occurs once it is mixed into fresh cement mixtures, limiting the nano-reinforcing efficiency for cement-based materials. In this study, an in-situ release strategy by pre-encapsulating nano-TiO 2 in microscaled ice and post-dispersing into fresh cement matrix during ice-melting process was developed to highly reinforce the microstructure and properties of cement paste. Compared with the conventional dispersion strategy, a much better dispersion of nano-TiO 2 (0.6 wt% by cement) was achieved using the in-situ release strategy, which not only improved the 7- and 28-day compressive strength of cement paste by 9.2% and 10.1%, respectively, but also reduced the cement hydration heat and water adsorption by 36.1% and 4.6%, respectively. In addition to this, the NO degradation efficiency of cement paste was also improved by 20% due to the larger exposed surface area of nano-TiO 2 with better dispersion. These research outcomes demonstrate that the in-situ release strategy facilitates the dispersion of nano-TiO 2 in cement matrix and contributes to highly reinforcing cement paste with lower hydration heat and water adsorption, strong mechanical strength and higher photocatalytic properties.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2019
·Vol. 137
·期 21
·48733
·
IF 2.188
Yuzheng Xia,Huan Cheng,Leijiao Duo,Dong Zhang,Xiaonong Chen,Shuxian Shi,Lei Lei
Photocathodic protection coatings have been widely applied in various areas such as ship and architectural protection, or chemical industry. In this work, a composite of titanium dioxide loaded with reduced graphene oxide (RGO/TiO 2 ) was prepared and used as filler on waterborne polyacrylate (PA) coating to reinforce the metal protection against corrosion. Compared with the current filler of zinc phosphate used for anticorrosive coating, the photoelectrochemical properties of RGO/TiO 2 -PA coating exhibit improved photocathodic protection under visible light illumination since RGO/TiO 2 composite has significant superiority in enhancing metal protection due to its dispersion, micropore blocking ability, and photoelectrochemical conversion performance. The mechanism of anticorrosion reinforcement of RGO/TiO 2 -PA coating was hypothesized that graphene provides an extrabarrier layer to obstruct corrosive in dark condition and photocathodic protection under lighting. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137 , 48733.
✓ 已验证
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2010
·
IF 1.669
Xiang-Chen Che,Yu-Zi Jin,Youn-Sik Lee
Stable nano-TiO 2 /polyurethane (PU) emulsions were prepared via in situ reversible addition-fragmentation chain transfer (RAFT) emulsion polymerization of 2-hydroxyethyl acrylate (HEA)-capped PU macromonomer, using azobisisobutyronitrile (AIBN) as a radical initiator and 2-{[(butylsulfanyl)carbonothioyl]sulfanyl} propanoic acid (BCSPA) anchored onto TiO 2 nanoparticles (TiO 2 -BCSPA) as a RAFT agent. When the molar ratio of AIBN to TiO 2 -BCSPA was changed from 1:3 to 1:10, the polydispersity index (PDI) of polymers in the emulsions decreased from 1.83 to 1.06, due to more effective RAFT polymerization in the emulsions. The TiO 2 nanofillers were well-dispersed throughout the polymer films . The tensile strengths of the nanocomposite films were significantly enhanced due to coordination bonding between the TiO 2 nanofillers and the –COOH end groups of the polymers, as evidenced by the FT-IR spectral data.
✓ 已验证
产品关联
DOI
高影响因子
Innovative Food Science & Emerging Technologies
·
2015
·
IF 3.273
Zixuan Lian,Yifeng Zhang,Yanyun Zhao
This study investigated the impact of nano-TiO 2 and high hydrostatic pressure (HHP) treatment on microstructure, water vapor and gas barrier, antibacterial and mechanical properties of polyvinyl alcohol (PVA)–chitosan (CHI) biodegradable films and determined the migration behavior of TiO 2 nanoparticles from the films to food simulants. Apart from the effect of filler, TiO 2 nanoparticles also could improve the antibacterial activity of the films and play a role as a plasticizer in the films. HHP treatment promoted the interaction between PVA and chitosan molecules, resulting in the formation of more compacted network structures in PVA–CHI films. The migration of TiO 2 from the films was investigated in food simulants including distilled water, acetic acid, ethanol and olive oil, in which the trace amount of TiO 2 (< 4.20 × 10 − 3 ‰) was only detected in olive oil. HHP treatment at 200–400 MPa significantly reduced migration of TiO 2 nanoparticles from the films. Industrial relevance Results from this study provide a new application direction of high hydrostatic pressure (HHP) in the field of food packaging materials for improving the functionality of materials. Due to the non-thermal characteristic, HHP in combination with nano-TiO 2 not only improved the mechanical and barrier properties of the biodegradable PVA–CHI composite films (polyvinyl alcohol and chitosan based materials), but also enhanced the antibacterial activity of the films. The HHP treated PVA–CHI–TiO 2 films are very stable in food simulants, such as olive oils. Therefore, the utilization of HHP and nano-TiO 2 is promising in the preparation of food packaging materials with desirable functionalities.
✓ 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）