Separations
·
2023
·Vol. 10
·期 6
·335
·
IF 2.6
Nian Wang,Die Zhou,Huaying Liu,Yina Tu,Yanqiong Ma,Yingjie Li
Photochemical generation is an important pathway for atmospheric sulfate formation. However, the roles of atmospheric co-existing photosensitive dissolved organic matter (DOM) in sulfate formation are still unclear. The experimental results in this work provide evidence that atmospheric photosensitizers produce active intermediates to oxidize S(IV) into S(VI) under illumination. Quenching experiments of eight photosensitive model compounds (PS) demonstrate that their triplet-excited states (3PS*) dominate sulfate formation for the photosensitizing pathway with a contribution of over 90%, and1O2plays an important role in sulfate formation. The results using humic acid (HA) and water-soluble organic carbon in vehicle exhaust particles (WSOC) as representatives of atmospheric photosensitizers further verify that triplet-excited DOM (3DOM*) is the main reactive species for sulfate formation, which is consistent with the results of PS. Our findings provide new insights into the photochemical formation pathways of atmospheric sulfate.Keywords:atmospheric oxidants;atmospheric sulfate;water-soluble organic carbon;aqueous-phase oxidation;triplet-excited states;photosensitization
研究领域:
大气化学
·
环境科学
·
光化学
✓ 已验证
产品关联
DOI
高影响因子
Applied Materials Today
·
2021
·
IF 10.041
Yue Hu,Zhou Fang,Xu Ma,Xinyi Wan,Shilin Wang,Shuaikang Fan,Zhizhen Ye,Xinsheng Peng
Harvesting water from atmosphere is emerging as a potential strategy to solve the problem of water scarcity. In this work, CaCl 2 encapsulated Fe-ferrocene MOFs hollow microspheres (CaCl 2 @Fe-Fc-HCPs) were successfully fabricated. CaCl 2 plays as water sorbent and Fe-Fc-HCPs act as photothermal components for rapidly water release. In CaCl 2 @Fe-Fc-HCPs composites, the dissolving CaCl 2 in the adsorbed water are effectively prevented, while the water adsorption capacity of the encapsulated CaCl 2 is improved. The amount of water adsorbed by CaCl 2 @Fe-Fc-HCPs (80% RH, 15 °C) is 2.685 g H2O /g CaCl2 , 2.23 times as that adsorbed by pristine CaCl 2 powder. Furthermore, the hollow structure Fe-Fc-HCPs MOFs favorable for loading CaCl 2 nanoparticles and facilitating mass transport. The adsorbed water can be easily released by a simulated solar light (one sun) due to the high efficient photothermal property of Fe-Fc-HCPs. The performance shows no degradation after 5 cycles, indicating its nice stability. This may provide a promising and cost-effective way to harvest water from air only powered by natural sunlight and offer new insights to combine photothermal MOFs with traditional adsorbents to design high-efficiency water generators.
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
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2012
·
IF 1.693
Xiao-Ming Peng,Yu-Feng Hu,Jin-Zhu Zhang,Zhi-Xin Wang,Zhe-Yu Li,Chao Miao
Viscosities were measured for the ternary systems Y(NO3)3 + Ce(NO3)3 + H2O, Y(NO3)3 + Nd(NO3)3 + H2O, and Ce(NO3)3 + Nd(NO3)3 + H2O and their binary subsystems Y(NO3)3 + H2O, Ce(NO3)3 + H2O, and Nd(NO3)3 + H2O at (293.15, 298.15, and 308.15) K and atmospheric pressure. The results were used to test the applicability of simple equations for the viscosity of mixed solutions. The predictions agree well with measured values, implying that the viscosities of the examined electrolyte solutions can be related to those of their constituent binary solutions using these simple equations.
研究领域:
化学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
ASTRONOMICAL JOURNAL
·
2017
·Vol. 153
·期 3
·138
·
IF 2.609
J. L. Birkby,R. J. de Kok,M. Brogi,H. Schwarz,I. A. G. Snellen
We report the detection of water absorption features in the day side spectrum of the first-known hot Jupiter, 51 Peg b, confirming the star–planet system to be a double-lined spectroscopic binary. We use high-resolution (R\approx 100,000), 3.2\,\mu {\rm{m}} spectra taken with CRIRES/VLT to trace the radial-velocity shift of the water features in the planet's day side atmosphere during 4 hr of its 4.23 day orbit after superior conjunction. We detect the signature of molecular absorption by water at a significance of 5.6\sigma at a systemic velocity of {V}_{\mathrm{sys}}=-33\pm 2 km s−1, coincident with the 51 Peg host star, with a corresponding orbital velocity {K}_{{\rm{P}}}={133}_{-3.5}^{+4.3} km s−1. This translates directly to a planet mass of {M}_{{\rm{p}}}={0.476}_{-0.031}^{+0.032}\,{M}_{{\rm{J}}}, placing it at the transition boundary between Jovian and Neptunian worlds. We determine upper and lower limits on the orbital inclination of the system of 70^\circ \lt i\lt 82\buildrel{\circ}\over{.} 2. We also provide an updated orbital solution for 51 Peg b, using an extensive set of 639 stellar radial velocities measured between 1994 and 2013, finding no significant evidence of an eccentric orbit. We find no evidence of significant absorption or emission from other major carbon-bearing molecules of the planet, including methane and carbon dioxide. The atmosphere is non-inverted in the temperature–pressure region probed by these observations. The deepest absorption lines reach an observed relative contrast of 0.9\times {10}^{-3} with respect to the host star continuum flux at an angular separation of 3 milliarcseconds. This work is consistent with a previous tentative report of K-band molecular absorption for 51 Peg b by Brogi et al.
研究领域:
天文学
·
行星科学
✓ 已验证
DOI
高影响因子
Crystals
·
2022
·Vol. 12
·期 7
·985
·
IF 2.67
Yuhan Feng,Yumin Zhang,Jipeng Liu,Ye Zhang,Yongshuai Xie
Due to its high thermal and chemical stability, excellent dielectric properties, unique optical properties, corrosion resistance, and oxidation resistance, the two-dimensional hexagonal boron nitride (h-BN) is often used in a thermal conductor protective layer in deep ultraviolet light-emitting detector fields. However, due to the complicated growth conditions of h-BN, it is often necessary to prepare h-BN by the CVD method in a high vacuum environment, which is limited to a certain extent in terms of film size and production cost. In order to solve this problem, we proposed a method to prepare h-BN thin films by atmospheric CVD (APCVD). This method does not need a vacuum environment, which reduces energy consumption and cost, and makes the operation simpler and the experimental environment safer. The preparation of high-quality h-BN film was carried out using a Cu-Ni alloy as the growth substrate. The growth process of h-BN film was studied, and the influence of growth parameters on the structure of the h-BN film was explored. The morphological features and elemental composition pairs of the samples were characterized and analyzed, which confirmed that the high-quality h-BN film could be successfully grown on the Cu-Ni alloy substrate by APCVD. The UV detection device prepared by using the prepared h-BN film as the photoresponse material had good photoresponse characteristics and performance stability. It provides a new idea for the low-cost preparation of large-scale h-BN.Keywords:APCVD;h-BN;film;photoelectric devices
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2020
·
IF 7.864
Chi Yang,Chunyan Zhang,Xiaosan Luo,Xiaoyan Liu,Fang Cao,Yan-lin Zhang
So far, studies on the conversion of stereochemistry under photo-Fenton conditions and their atmospheric implication are still rare. Here, we found that the biomass burning marker, the chiral compound levoglucosan (L), undergoes oxidative degradation under photo-Fenton conditions and can be isomerized into mannosan (M) and galactosan (G) simultaneously. Among the formic acid, acetic acid, and oxalic acid in the degradation products of levoglucosan, it was found that the yield of formation of formic acid in the photo-Fenton pathway can be as high as 86%. It is worth noting that both levoglucosan and its isomers are present in the atmosphere and their concentrations are strongly correlated. At the same time, the range of their concentration ratios, L/(G + M), measured in the photo-Fenton experiments in the laboratory was found to agree well with that measured in atmospheric PM2.5 samples. However, the sources of L, G, and M in the atmosphere are complex, and the photo-Fenton reaction may be an essential pathway for the distribution of L, G, and M in the atmosphere.
研究领域:
环境科学
·
大气化学
✓ 已验证
DOI
高影响因子
ATMOSPHERIC ENVIRONMENT
·
2020
·
IF 4.039
Yunchao Wu,Xiaoping Huang,Zhijian Jiang,Songlin Liu
The phosphorus in precipitation provides a significant fraction of the bioavailable phosphorus to fresh and marine waters. To identify the possible sources and interpret the atmospheric deposition processes of phosphorus, we measured the phosphate oxygen isotopes (δ 18 O P ) in the precipitation monthly from October 2015 to March 2017 in Daya Bay, South China Sea. The isotopic results show that the δ 18 O P values in the dry season (+19.60‰ to +25.80‰, +23.10‰ average) were significantly higher than those in the wet season (+12.52‰ to +20.11‰, +16.73‰ average), indicating a variable contribution from different phosphorus sources to the precipitation between seasons. The δ 18 O P value was primarily influenced by the phosphorus concentrations, rainfall, and air temperature. The exchange of phosphate molecules among phosphorus pools caused isotope dilution (wet season) or enrichment effects (dry season) during the seasonal shifts. The δ 18 O P value of the precipitation and the local end-members indicate that coal combustion (39% ± 16%), biomass burning (22% ± 18%), and soil (17% ± 13%) sources dominate in the dry season, whereas marine sources (28% ± 19%) and coal combustion (24% ± 12%) account for the highest proportion in the wet season using a MixSIAR model. The atmospheric wet deposition flux of phosphorus in Daya Bay was 379.0 μmol m −2 ·yr −1 . The wet deposition of phosphorus exhibits a significant seasonal trend with higher deposition fluxes in the wet season than in the dry season as a result of higher rainfall and source shifts (local sources to marine source) between seasons.
研究领域:
环境科学
·
海洋学
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2020
·
IF 6.551
Xi Mu,Zhanxiang Wang,Lichun Liu,Xiaohong Guo,Chen Gu,Hua Xu,Liuyuan Zhao,Wanyanhan Jiang,Hongmei Cao,Xiaoxuan Mao,Tao Huang,Hong Gao,Jianmin Ma
In this study, we collected 308 serum samples from 17 to 20 year old first-year university students who were recruited from Lanzhou University in China a few days after their enrollment to measure the serum Pb, Cd, Hg, and As levels, and specific questionnaires for age, sex, settlement and dietary structure were designed. A 3-D atmospheric transport model was used to simulate the atmospheric concentration and dry deposition across China based on gridded Pb emission inventory to examine the association between the spatial distribution of serum concentrations and environmental fates of Pb. The mean serum Pb, Cd, Hg, and As concentrations averaged over all participating young students were 21.38, 1.46, 3.86, and 4.69 μg/L, respectively. The Pb, Cd, and Hg levels in 3%, 7%, and 20% serum samples exceeded the standards. The minimum serum As and Hg concentrations and the maximum serum Pb and Cd concentrations occurred in urban areas. Seafood diet habits ( P < 0.05), sex ( P < 0.05), and relocation ( P < 0.01) caused significant differences in serum As, Pb, and Cd concentrations. A cluster analysis was carried out to classify the exposure pathways for target contaminants. The results indicated that 4 heavy metals in the serum of volunteers from northern China could be grouped into the same category, in which significant positive correlations were found between the serum heavy metal levels and background concentrations of surface soil. However, in other provinces and metropolises, the atmospheric pollution level played a critical role involving in the inhalation exposure pathway. We demonstrated that serum Pb levels in freshman students were related to the atmospheric transport and dry deposition of Pb.
研究领域:
环境科学
·
公共卫生
·
毒理学
✓ 已验证
DOI
PubMed
高影响因子
FUEL
·
2016
·
IF 3.611
Shunlin Tang,Lina Wang,Xinbin Feng,Zhaohui Feng,Ruiyang Li,Huipeng Fan,Ke Li
Mercury species distribution in the flue gas from three typical coal-fired power plants have been investigated using a C-5000 sampler for Ontario Hydro Method (OHM) to evaluate specified Hg emission inventories in the largest coal-production province of China, Inner Mongolia. The feed coal, bottom ash, fly ash and gypsum have also been sampled in the field. Mercury emissions are in the dominant form of Hg 0 (>85%). The Hg 2+ (<15%) and the Hg p (<2%) emissions are minor fractions of Hg t in the flue gas. The wet limestone flue gas desulfurization device (WLFGD) showed much higher removal efficiency for Hg 2+ (87–95%) than for the other two Hg species. The input Hg/output Hg varied from 92% to 115% for the tested 3 coal-fried utility boilers during sampling time. We obtained comprehensive Hg discharge factors, including direct atmospheric Hg emission factors and indirect discharge factors of Hg associated with bottom ash, fly ash and gypsum, to the environment, designating the fates of Hg in coal. We estimated the Hg discharges from coal-fired power plants in Inner Mongolia in 2008–2014 and expanded to China. The maximum of direct Hg emissions from coal-fired power plants of Inner Mongolia was 24 Mg in 2012. The Chinese coal-fired power plants emitted directly 100 Mg Hg to the atmosphere every year at the nationwide air control actions. The maximum discharges of Hg associated with fly ash and gypsum of Inner Mongolia was 81 Mg and 11 Mg in 2012, respectively. The national Hg discharges with fly ash and gypsum every year are respectively about 300 Mg and 82 Mg, majority of which may be reemitted to the atmosphere by the utilization industry. Therefore, mercury emissions from coal-fired power plants are not the largest single source of Hg to the atmosphere in normal operation of the current efficient denitrification, particles control and desulfurization devices. Instead, the utilization industry of fly ash and gypsum would be emitting more Hg to the atmosphere.
研究领域:
环境科学
·
能源与动力工程
✓ 已验证
产品关联
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·
IF 1.5
Xiaoming Wang,Xingeng Li,Xuelei Tian,Kai Guo
Both the effect of forming conditions on corrosion resistance of phytic acid conversion coating on zinc in air and the influence of ambient factors (temperature and relative humidity) on service of conversion coating were studied by SEM, EDS, ACM and SKP. Zinc-graphite ACM sensors and zinc plates were treated with phytic acid solution at different processing time and pH values. The results showed that longer processing time and alkalinity phytic acid solution weaken the corrosion resistance of treated zinc. Self-assembled monolayer of zinc phytate provided the best protection. The corrosion resistance of conversion coating with phytic acid solution was reduced when the ambient temperature or relative humidity is high values, which due to the zinc phytate bond strength with zinc matrix and co-adoption water on it.
研究领域:
材料科学
·
腐蚀与防护
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·
IF 7.2
Bin Shang,Junhao Chen,Mengyao Zhu,Huiyu Yang,Pei Lyu,Jiehao Du,Jingjing Huang,Xin Liu,Shaojin Gu
Sorption-based atmosphere water harvesting (SAWH) is considered to be a promising solution to the global freshwater crisis. However, a high moisture absorption capacity, rapid moisture ab/desorption kinetics, and flexible desorption options are crucial for high-performance SAWH materials, but related research is scare. Here, a sandwich-structured atmosphere water harvester based on carbon cloth (CC), MXene nonosheets, sodium alginate (SA), and lithium chloride (LiCl) was fabricated via vacuum-assisted filtration and freeze-drying methods. On the one hand, the coordination of hygroscopic LiCl and porous film structure confer it with a high moisture absorption capacity and fast moisture absorption kinetics (moisture absorption of approximately 1.79 g g −1 after 4 h moisture absorption at 50 % RH, 25 °C); on the other hand, the conductive CC and photothermal MXene make it flexibly choose to release the absorbed water through solar irradiation (76 % of the absorbed water is released within 40 min, 1 kW m −2 ) or electrical heating (98 % of the absorbed water is leased within 10 min, 1.3 A). As a proof of concept, the daily water yield at 50 % RH with solar heating is approximately 7.01 kg kg −1 , which with electrical heating can reach 8.98 kg kg −1 in a lab environment, both of them are comparable to most of the hygroscopic salts-SAWH materials. The proposed sandwich-structured atmosphere water harvester with dual solar and electrical heating capacities has excellent moisture absorption performance and enriched water release routes, which has great means for designing of high-performance SAWH materials.
研究领域:
环境工程
·
材料科学
·
能源技术
·
化学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL POLLUTION
·
2025
·
IF 7.3
Xinyue Zhao,Siyu Liu,Lina Wang,Li Yang,Jun He,Chengjun Wang
A gas chromatography-flame ionization detection method was developed to investigate the occurrence and transformations of phthalate esters (PAEs) in atmospheric aqueous aerosol in Wuhan City. Six of PAEs were detected in collected aerosol samples and their concentrations in atmosphere were followed the order of diallyl phthalate (0.244 μg m −3 ) > diethyl phthalate (0.235 μg m −3 ) > di(2-ethylhexyl) phthalate (0.176 μg m −3 ) > dimethyl phthalate (0.110 μg m −3 ) > di-n-octyl phthalate (0.081 μg m −3 ) > dipropyl phthalate (0.024 μg m −3 ). The Redundancy analysis results indicated that, compared to humidity and wind speed, temperature had the most important influence on the occurrence of PAEs in aqueous aerosol. The hydrolysis of selected PAEs in aqueous extracts of aerosol samples was examined under different conditions, determining that hydrolysis of PAEs is most susceptible to the ambient temperature at typical atmospheric aqueous pH of 3–5. In addition, photodegradation results suggested that indirect photodegradation played a key role in photodecomposition of PAEs under sunlight irradiation. The photo-generated reactive species including triplet water-soluble organic matter ( 3 WSOM∗) and reactive oxygen species (ROS) mainly contribute to the degradation of PAEs in atmospheric aqueous aerosol. This study provides an important reference for better understanding the occurrence and transformations of PAEs in ambient urban atmospheric aqueous aerosol.
研究领域:
环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）