CHEMOSPHERE
·
2021
·
IF 7.086
Bing Yuan,Hongyun Hu,Yongda Huang,Biao Fu,Huimin Liu,Guangqian Luo,Yongchun Zhao,Hong Yao
Gaseous selenium is of high saturated vapor pressure , making its retention in solid phases quite difficult during coal combustion . The selenium transformation from gaseous form into solid phases at low temperatures can be essential to control selenium emission. To understand the migration of SeO 2 (g) on ash particles in the low-temperature zone, this study investigated the speciation of selenium in fly ash and simulated the physical retention of SeO 2 (g) on fly ash. The results demonstrated that there was a large proportion of physically-bound Se in the fly ash of pulverized-coal-fired boiler (22.62 %–58.03%), while the content of physically-bound Se in fly ash of circulated fluidized-bed boiler was lower (∼6%). The physically-bound Se was formed through selenium condensation and physical adsorption. The decrease of temperature or the increase of cooling rate could promote the transformation of gaseous selenium to solid phase and the presence of HCl might suppress SeO 2 transformation into Se in the condensation process . Meanwhile the compositions of fly ash had a great influence on the selenium adsorption process. Among typical coal-fired ash components, mullite showed the best performance in the selenium capture in the temperature range of 90–200 °C, contributing to the high content of physically-adsorbed selenium in PC fly ash. These findings provided new ideas for improving the removal rate of volatile selenium.
研究领域:
环境科学
·
能源与燃料
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials
·
2023
·Vol. 16
·期 4
·1620
·
IF 3.4
Yihong Zhang,Yong Wu,Puyu Zhou,Zhiyuan Song,Yayun Jia,Weiyi Ouyang,Rafael Luque,Yang Sun
Aluminum sulfate was employed as the main accelerator in order to explore new non-chloride and alkali-free cement accelerators. Acrylic acid, aluminum fluoride, or alkanolamine were used as regulators to further accelerate cement setting. The setting time, compressive, and flexural strengths in cement early strength progress were detected, and both the cement (raw material) and hydrated mortar were fully characterized. The cement setting experiments revealed that only loading acrylic acid as the regulator would decrease the setting time of cement and increase the compressive and flexural strengths of mortar, but further introduction of aluminum fluoride or alkanolamine improved this process drastically. In the meantime, structural characterizations indicated that the raw material (cement) used in this work was composed of C3S (alite), while hydrated mortar consisted of quartz and C3A (tricalcium aluminate). During this transformation, the coordination polyhedron of Al3+was changed from a tetrahedron to octahedron. This work puts forward a significant strategy for promoting the activity of aluminum sulfate in cement setting and would contribute to the future design of new non-chloride and alkali-free cement accelerators.Keywords:aluminum sulfate;accelerator;setting time;mortar;strength
研究领域:
材料科学
·
土木工程
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产品关联
DOI
PubMed
高影响因子
SOLAR ENERGY
·
2024
·
IF 6
Wuzhi Yuan,Huaming Li,Kui He,Ya Ge,Si-Min Huang
Dust on the PV surface is well known to cause significant losses in energy yield. Complex physical and chemical interactions occur between dust and condensate on the surface of PV module under condensation, which determine the mode and severity of surface contamination. In this work, dynamic behavior of dust particle on surface is investigated from a microscopic perspective. Dust mainly experiences particle aggregation, dusty droplet coalescence, growth, movement and drying. After condensation & drying, surface transmittance is quantitatively measured to provide an assessment of surface contamination. The results show that for SiO 2 and Al 2 O 3 particles, that do not react with condensate, surface transmittance increases after drying, especially for superhydrophobic surface (SHS). However, CaO particle easily react with condensate and atmospheric carbon dioxide to form insoluble substances. After drying, a dense layer of dust is formed on the hydrophilic surface with transmittance of 49.2 %. SHS has excellent ability of self-cleaning and it increases with extension of condensation time. As condensation time is 120 min, transmittance of SiO 2 -contaminated SHS can recover to 99.1 % of clean surface. This finding may guide for development of suitable strategies to prevent or mitigate surface-soiling under condensation.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
NANO
·
2021
·
IF 1.556
Xintao Chen,Xian Wu,Fang Li,Xiaofeng Zhao,Shanlin Wang
Hydrophilic–hydrophobic hybrid wettability structures, inspired by desert beetles, have been widely designed to enhance the dewdrops’ migration under subcooled or/and high-humidity environment. However, it is still a challenge to regulate the graded distribution of the hydrophilic micro-regions for condensation applications. In this paper, we design a simple spray method to prepare the superamphiphilic–superamphiphobic hybrid wettability coatings by controlling the mass ratio (MR) of superamphiphobic SiO 2 nano-powder and superamphiphilic gypsum micro-powder. We compare the macroscopical wettability, condensation heat transfer efficiency, frosting delayed time and water harvesting rate to demonstrate the unique advantage of hybrid wettability structures. The results show that the condensation heat transfer efficiency, frosting delayed time and water harvesting rate can be respectively promoted to about 131.50% ( MR = 1 : 0 . 5 ) , 134.74% ( MR = 1 : 0 . 5 ) and 135.62% ( MR = 1 : 1 ) , although their macroscopical wettability will gradually reduce with the MR increase. This work will provide substantial insights into the fabrication of efficient superhydrophilic–superhydrophobic hybrid wettability surfaces for condensation heat transfer, anti-frosting and water harvesting applications.
研究领域:
材料科学
·
热力学
·
表面工程
✓ 已验证
DOI
高影响因子
ATMOSPHERIC ENVIRONMENT
·
2022
·
IF 5.755
Na Wang,Yaxin Guo,Jiarong Li,Shufeng Pang,Yunhong Zhang
Water-soluble amino acids have been confirmed as effective cloud condensation nuclei (CCN) materials. While their influence on the hygroscopicity of nitrates is still scarcely known. In this work, ammonium nitrate (AN) was mixed with glycine and alanine at various mole ratios to form internally mixed particles deposited onto a solid substrate, whose hygroscopic properties and phase states of ingredients were investigated using microscope and attenuated total reflection-Fourier transformed infrared spectroscopy (ATR-FTIR). For mixed AN/amino acid particles with abundant inorganic, AN crystallizes at lower RH than that of pure AN, while deliquescence relative humidities (DRHs) were close to pure AN. On hydration, the mixture composed of bis(amino acid) nitrates and mono(amino acid) nitrates formed at 14.6–60.8% RH and 23.6%–60.0% RH for AN/glycine and AN/alanine particles, respectively. When the inorganic and organic components were mixed with equal mole ratio, gradual water uptake and release took place due to the hygroscopic interplay between components. In the mixed particles with abundant amino acids, glycine and alanine still kept solid at highest RH on hydration. Hydrogen bonding interaction should account for the mutual suppression on individual crystal formation. The present hygroscopic study would help people understanding cloud condensation nuclei (CCN) ability of amino acids in atmosphere.
研究领域:
大气科学
·
化学
✓ 已验证
DOI
高影响因子
Scientific Reports
·
2014
·Vol. 4
·期 1
·1-5
·
IF 5.078
Yi Nan,Huang Bin,Dong Lining,Quan Xiaojun,Hong Fangjun,Tao Peng,Song Chengyi,Shang Wen,Deng Tao
This report investigates the impact of droplet temperature on the head-on collision of binary droplets on a superhydrophobic surface. Understanding droplet collision is critical to many fundamental processes and industrial applications. There are many factors, including collision speed, collision angle and droplet composition, that influence the outcome of the collision between binary droplets. This work provides the first experimental study of the influence of droplet temperature on the collision of binary droplets. As the droplet temperature increases, the possibility increases for the two droplets to coalesce after collision. The findings in this study can be extended to collision of droplets under other conditions where control of the droplet temperature is feasible. Such findings will also be beneficial to applications that involve droplet collision, such as in ink-jet printing, steam turbines, engine ignition and spraying cooling.
研究领域:
物理学
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工程学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2018
·
IF 4.439
Hu Luo,Shaohui Yin,Shuai Huang,Fengjun Chen,Qingchun Tang,Xiaojie Li
Zinc and its alloys are valuable crucial materials applied in the fields of automobile, ship manufacturing and construction industries. However, their application is limited due to poor performance on water-resistance, condensation and anti-icing property. Slippery liquid-infused porous surface (SLIPS) has been widely used owing to excellent water-repellent, condensation and anti-icing properties. In this work, a SLIPS was fabricated based on zinc substrate by using electrochemical etching, low surface energy modification and lubricant infusion, successively. According to the SEM morphologies and EDS images, it could be confirmed that the rough porous surface structure, low surface energy modification and infused lubricants are key factors accounting for the excellent anti-wetting property of fabricated slippery Zn surface. The experimental results showed that the SLIPS on zinc substrate exhibited outstanding water-repellent performance at a wide range of temperature and drop impact velocity. Moreover, its anti-wetting ability can be sustained even under the impacts of droplets or the continuous water jet. Owing to its dropwise condensation strategy, the SLIPS shows reasonable water collection efficiency, which exceeds 60 mg/(cm 2 ·h) at relative humidity of 90%. The excellent anti-icing property is demonstrated by the simulated ice rain test and deicing force test. And the results showed that only tiny residue ice left on the SLIPS and the deicing force was 2–3 times smaller than ordinary surface. The prepared SLIPS is expected to be an adaptable and efficient method for enhancing the water-repellent, condensation and anti-icing properties of zinc substrate, and may expand the application in energy-efficient fluid handing & transportation, medicine and anti-fouling operating in low temperature environment.
研究领域:
材料科学
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表面工程
✓ 已验证
产品关联
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2022
·
IF 7.305
Wu-zhi Yuan,Zhixing Liao,Kui He,Si-Min Huang
Although condensation plays an important role in photovoltaic (PV) soiling, the mechanism of interaction among the condensate, dust particle, and PV surface has not been effectively elucidated. In this work, the dynamic behavior of dust/condensate during condensation and evaporation is investigated. Further, quantitative measurements are performed after drying. In addition, the effects of surface wettability and dust types on soiling are studied. A surface with a hydrophobic coating is found to have enhanced dust rearrangement/agglomeration by reducing surface coverage and particle adhesion . However, the hydrophobicity of particles is unfavorable because of the weak water-solid force. Based on these results, an explanative mechanism for the morphology and spatial distribution of dust mass after drying according to the force analysis is proposed. Two mechanisms account for surface soiling in the presence of dew: contact status between condensate and particles and condensation mode on the surface. This finding may guide the development of suitable strategies to prevent or mitigate soiling.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Sciences
·
2019
·
IF 3.556
Xuejun Xiong,Hui Xu,Beiping Zhang,Xiaohui Wu,Hongyan Sun,Dongsheng Wang,Zhengyang Wang
Membrane filtration combined with pre-coagulation has advantages in advanced wastewater treatment . As a model of a microbial polysaccharide , research on the effect of sodium alginate (SA) on alum hydrolysis has been rare; therefore, it is necessary to gain insight into the interface interaction between SA molecules and Al species, and the role SA plays during floc formation. In this study, the interaction mechanism between SA and Al species has been investigated, by evaluating the effect of SA on floc characteristics and membrane fouling during coagulation–ultrafiltration with different Al species coagulants (AlCl 3 and preformed Al 13 ). Al 2p X-ray photoelectron spectroscopy (XPS) confirmed that the complexation of ligands and Al species strongly affects the reaction pathways for Al hydrolysis and the final nature of the flocs, as Al 13 can be decomposed into octahedral precipitates when SA is added. The presence of SA can affect floc properties, which have important impacts on the characteristics of the cake layer and membrane fouling. Due to the bridging ability of SA, the floc strength increased by about 50% using Al a , which was much better than preformed Al 13 , with a percentage increase of only about 6%. Moreover, the recovery factor of HA-flocs was decreased from 96% to 43% with SA addition of 0.5 mg/L. It was concluded that SA can affect the characteristics of the cake layer and membrane fouling through participating in the formation of primary flocs and altering the Al hydrolysis pathway.
研究领域:
环境科学
·
水处理工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Jiwei Xu,Qianqian Tian,Yifan Li
Facilitated transport membranes with high CO 2 /CH 4 separation performance under humidified state have shown great prospects for biogas purification. The role of water might include the formation of condensed water film on membrane surface, but it was seldom verified and investigated. In this study, the condensation of water film on polyamide (PA) thin-film composite membrane was performed and regulated. Thanks to the absence of active carrier groups that can reversibly with CO 2 , the contribution of water to facilitated transport can be neglected, and the truth of condensing-water membrane was allowed to be explored. The PA layer was fabricated by interfacial polymerization with its hydrophilicity tuned by polyvinyl alcohol . The regulation of water film is based on three operational approaches: simple humidifying the feed gas, pre-wetting the membrane, or heating the humidifier. The remarkable increment of selectivity along with the improvement of water-condensing conditions implied the formation of condensed water film. Fortunately, the series of gas permeation data allowed the estimation of water film thickness according to the mass transfer resistance model for multilayer composite membranes. The decline of selectivity over time under elevated pressure was found effective to evaluate the stability of such condensing water membranes. The results show that a polyamide thin-film composite membrane with poor CO 2 /CH 4 selectivity under dry state can achieve rather high performance (CO 2 permeance 374 GPU and CO 2 /CH 4 selectivity 31 for 16 days under 3.25 bar) with the aid of a simple condensed water layer. Hopefully, it provides a method to re-evaluate the effect of water on a given facilitated transport membrane, and possibilities of further enhancing its separation performance by fine tuning the condensed water film.
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
Surfaces and Interfaces
·
2024
·
IF 5.7
Jun Hu,Zhan-Long Wang
Condensation is a ubiquitous natural phenomenon with both detrimental and beneficial implications. The key point to minimize its harmful effects while harnessing its potential for various applications is the spatial controlling of condensation. In recent years, using hygroscopic liquids for spatially controlling condensation has gradually emerged as a promising strategy. However, the underlying mechanisms and influencing parameters of controlling condensation with hygroscopic liquids remain insufficiently understood. In this paper, the effect of hygroscopic droplets in suppressing condensation on low-temperature surfaces, specifically -15 ℃ to 15 ℃, under different conditions, including substrate temperature, cooling time, droplet volume are studied. A typical hygroscopic liquid, dipropylene glycol, was employed to illustrate this issue. The results indicated that distinct ring-shaped dry zone forms around dipropylene glycol droplets on low-temperature surfaces, evidencing their efficacy in inhibiting condensation. Experiments and theoretical analysis reveal that the ratio of the dry-zone radius to the droplet radius is a function of substrate surface temperature, scaling as 1/( T dew - T c ). The results also show that cooling time has a negligible effect on this ratio over short periods. Furthermore, the ratio slightly decreases with increasing droplet volume at higher substrate temperatures, while remaining nearly constant at lower temperatures. These findings may enhance our understanding of the condensation inhibition effect of hygroscopic droplets and also provide valuable insights for potential applications in condensation control.
研究领域:
材料科学
·
热力学
✓ 已验证
DOI
高影响因子
PHYSICS OF FLUIDS
·
2024
·Vol. 36
·期 6
·
IF 4.1
Hu Jun,Zhao Haonan,Xu Zhen,Hong He,Wang Zhan-Long
Anti-condensation is important in various fields, e.g., transportation, power transmission, internal drying of precision instruments. Vapor sink is an important manner to suppress the happening of water vapor condensation, and shows potentials in some special scenarios. However, the mechanism of anti-condensation by vapor sink is not well understood up until now. In this article, the effect of substrate temperature on the dry zone generated by vapor sink were systematically studied with experiments and theoretical analysis. First, the effect of hygroscopic solutions on the local humidity were measured. The results indicated that the local humidity level near the hygroscopic solutions was effectively suppressed, reducing the water vapor condensation. Second, the variation of the dry zone with the cooling substrate temperature was systematically studied. The results indicated that the dry zone exhibits a hyperbolic relationship with the substrate temperature. The dry zone changing under different humidity conditions and cooling time were also studied. The dry zone remained approximately unchanged over time in a short period. Finally, a simple yet effective model between the dry zone and substrate temperature was deduced. The theoretical results are in good agreement with the experimental data. Our study may deeper the understanding of condensation suppression via vapor sink and offer guidance to the design of anti-condensation or anti-icing surfaces.
研究领域:
工程热物理
·
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）