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National Science Review 2024年第3期11卷 150-158页

作者： Kun Li Jun Zhang David M.Bell Tiantian Wang Houssni Lamkaddam Tianqu Cui Lu Qi Mihnea Surdu Dongyu Wang Lin Du Imad El Haddad Jay G.Slowik Andre S.H.Prevot environment Research institute Shandong University Laboratory of Atmospheric Chemistry Paul Scherrer Institute

Organic vapors from biomass burning are a major source of secondary organic aerosols(SOAs). Previous smog chamber studies found that the SOA contributors in biomass-burning emissions are mainly volatile organic compounds(VOCs). While intermediate volatility organic compounds(IVOCs) are efficient SOA precursors and contribute a considerable fraction of biomass-burning emissions, their contribution to SOA formation has not been directly observed. Here, by deploying a newly-developed oxidation flow reactor to study SOA formation from wood burning, we find that IVOCs can contribute ～70% of the formed SOA, i.e.>2 times more than VOCs. This previously missing SOA fraction is interpreted to be due to the high wall losses of semi-volatile oxidation products of IVOCs in smog chambers. The finding in this study reveals that SOA production from biomass burning is much higher than previously thought, and highlights the urgent need for more research on the IVOCs from biomass burning and potentially other emission sources.

关键词： atmospheric chemistry biomass burning secondary organic aerosol intermediate volatility organic compounds

Temperature variability caused by internal tides in the coastal waters of east coast of Peninsular Malaysia

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Acta Oceanologica Sinica 2019年第1期38卷 22-31页

作者： Nur Hidayah Roseli Mohd Fadzil Akhir institute of Oceanography and environment Universiti Malaysia Terengganu

The effects of tidal currents(i.e., barotropic and internal tides) are important in the biogeochemistry of a coastal shelf sea. The high-frequency of currents and near-bottom temperatures collected in three consecutive southwest monsoon seasons(May, June, July and August of 2013 until 2015) is presented to reveal the role of the tidal currents to the temperature variability in the coastal shelf sea of the east coast of Peninsular Malaysia(ECPM),south of the South China Sea(SCS). The results of a spectral density and harmonic analysis demonstrate that the near-bottom temperature variability and the tidal currents are influenced by diurnal(O_1 and K_1) and semidiurnal(M_2) tidal currents. The spectral density of residual currents(detided data) at 5, 10 and 16 m depth also shows significant peaks at the diurnal tidal frequency(K_1) and small peaks at the semidiurnal tidal frequency(M_2)indicating the existence of internal tides. The result of the horizontal kinetic energy(HKE) shows a strong intermittent energy of internal tides in the ECPM with the strongest energy is found at 16 m depth during a sporadic cooling event in June and July. A high horizontal cross-shore heat flux(16 m) also indicates strong intrusions of cooler water into the ECPM in June and July. During the short duration of cold pulse water observed in June and July, a cross-wavelet analysis also reveals the strong relationship between the near-bottom temperatures and the internal tidal currents at the diurnal tidal frequency. The intrusion of this cooler water is probably related to the monsoon-induced upwelling in June. It is loosely interpreted that the interaction between the strong barotropic tides and the steep slope in the central basin of the SCS under the stratified condition in southwest monsoon has generated these internal tides. The dissipation of internal tides from the slope area probably has driven the cold-upwelled water into the ECPM coastal shelf sea when the upwelling intensity is th

关键词： east coast of Peninsular Malaysia South China Sea barotropic tidal currents internal tides nearbottom temperature coastal shelf sea

Ichnofabrics and Their environmental Interpretation from the Fluvial Deposits of the Middle Triassic Youfangzhuang Formation in Western Henan, Central China

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Journal of Earth Science 2014年第4期25卷 648-661页

作者： Min Wang Yongan Qi Da Li Mingyue Dai Yuguang Chang institute of Resources and environment Henan Polytechnic University

Fluvial deposits from the Middle Triassic Youfangzhuang Formation in Henan Province, China contain a low-diversity trace fossils. Vertical dwelling burrows of opportunists dominate in active channel, whereas horizontal deposit-feeding, grazing, and vertical dwelling burrows occur in overbank deposits. Seven recurrent ichnofabrics were distingushed. The Palaeophycus tubularis ichnofabric pre- serves below scour interface between two fluvial cycles. The Skolithos linearis ichnofabric forms in middle to high-energy, soft substrates in the middle and upper parts of active channel deposits under semi-arid climate. The Skolithos linearis-Planolites montanus ichnofabric occurs in the sediments just a little above the Skolithos linearis ichnofabric and is formed in middle-energy, soft substrates in the up- per part of active channel deposits. The Planolites montanus ichnofabric is mostly preserved in associa- tion with medium- to thick-bedded brown-red silty mudstones or siltstones in low-energy, perennial muddy bottom ponds in overbank settings. The Taenidium barretti ichnofabric is interpreted as peri- odically exposed ephemeral ponds or low-energy distal floodplain. The Skolithos isp. ichnofabric com- monly occurs in middle to high-energy firm ground of proximal foodplain or crevasse-splay deposits. The root trace iehnofabric occurs in the crevasse splay deposits. The presence of thin palaeosols and the abundance of calcretization in mudstones indicate a seasonal climate ranging from humid to semi-arid, with high temperature, rainfall, and well-defined dry and wet seasons.

关键词： trace fossil ichnofabric fluvial deposit environmental interpretation Middle Triassic Youfangzhuang Formation.

Influences and drivers of woody debris movement in urban watercourses

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Science China(Technological Sciences) 2014年第8期57卷 1512-1521页

作者： ALLEN Deonie ARTHUR Scott HAYNES Heather WALLIS Stephen G WALLERSTEIN Nicholas institute for Infrastructure and environment Heriot-Watt University

It is recognised that the blockage of culverts by woody debris can result in an increased risk of infrastructure damage and *** date,debris transport analysis has focused on regional fluvial systems and large woody debris,both in flume and field *** the social and economic risk associated with urban flooding,and as urban drainage design shifts away from subsurface piped network reliance,there is an increasing need to understand debris movement in urban *** prediction of urban watercourse small woody debris(SWD)movement,both quantity and risk,has undergone only limited analysis predominantly due to lack of field *** paper describes the development of a methodology to enable the collection of accurate and meaningful SWD residency and transportation data from *** presented research examines the limitations and effective function of PIT tag technology to collect SWD transport data in the field appropriate for risk and prediction *** integrated transponder(PIT)technology provides a method to collect debris transport data within the urban *** this study,the tags are installed within small woody debris and released at known locations into a small urban natural watercourse enabling monitoring of movement and travel *** velocity and detention are collated with solute time of travel,watercourse and point flow characteristics to identify the relationships between these key *** work presented tests three hypotheses:firstly,that the potential for unobstructed or un-detained SWD movement increases with flow velocity and water ***,that SWD travel distance,and the resistance forces along this travel path,influence SWD transport ***,the relationship between SWD and channel dimensions is examined with the aim of advancing representative debris transport prediction modelling.

关键词： woody debris transport prediction urban flood risk blockage solute dye tracing

One-pot hydrothermal fabrication of BiVO_(4)/Fe_(3)O_(4)/rGO composite photocatalyst for the simulated solar light-driven degradation of Rhodamine B

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Frontiers of environmental Science & Engineering 2022年第3期16卷 105-120页

作者： Shuangyang Zhao Chengxin Chen Jie Ding Shanshan Yang Yani Zang Nanqi Ren State Key Laboratory of Urban Water Resource and environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China

Fabrication of easily recyclable photocatalyst with excellent photocatalytic activity for degradation of organic pollutants in wastewater is highly desirable for practical *** this study,a novel ternary magnetic photocatalyst BiVO_(4)/Fe_(3)O_(4)/reduced graphene oxide(BiVO_(4)/Fe_(3)O_(4)/rGO)was synthesized via a facile hydrothermal *** BiVO_(4)/Fe_(3)O_(4) with 0.5 wt%of rGO(BiVO_(4)/Fe_(3)O_(4)/0.5%rGO)exhibited superior activity,degrading greater than 99%Rhodamine B(RhB)after 120 min solar light *** surface morphology and chemical composition of BiVO_(4)/Fe_(3)O_(4)/rGO were studied by scanning electron microscopy,X-ray diffraction,X-ray photoelectron spectroscopy,UV–visible diffuse reflectance spectroscopy,Fourier transform infrared spectroscopy,and Raman *** free radicals scavenging experiments demonstrated that hole(h^(+))and superoxide radical(O_(2)•^(−))were the dominant species for RhB degradation over BiVO_(4)/Fe_(3)O_(4)/rGO under solar *** reusability of this composite catalyst was also investigated after five successive runs under an external magnetic *** BiVO_(4)/Fe_(3)O_(4)/rGO composite was easily separated,and the recycled catalyst retained high photocatalytic *** study demonstrates that catalyst BiVO_(4)/Fe_(3)O_(4)/rGO possessed high dye removal efficiency in water treatment with excellent recyclability from water after *** current study provides a possibility for more practical and sustainable photocatalytic process.

关键词： Photocatalysis Ternary magnetic photocatalyst Visible-light-driven Free radicals trapping Reusability Recycling

Forward osmosis coupled with lime-soda ash softening for volume minimization of reverse osmosis concentrate and CaCO_(3) recovery: A case study on the coal chemical industry

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Frontiers of environmental Science & Engineering 2021年第1期15卷 135-144页

作者： Jiandong Lu Shijie You Xiuheng Wang State Key Laboratory of Urban Water Resource and environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China

Reverse osmosis(RO)is frequently used for water reclamation from treated wastewater or desalination *** RO concentrate(ROC)produced from the coal chemical industry(CCI)generally contains refractory organic pollutants and extremely high-concentration inorganic salts with a dissolved solids content of more than 20 g/L contributed by inorganic ions,such as Na^(+),Ca^(2+),Mg^(2+),Cl^(−),and SO_(4)^(2−).To address this issue,in this study,we focused on coupling forward osmosis(FO)with chemical softening(FO-CS)for the volume minimization of CCI ROC and the recovery of valuable resources in the form of CaCO_(3).In the case of the real raw CCI ROC,softening treatment by lime-soda ash was shown to effectively remove Ca^(2+)/Ba^(2+)(>98.5%)and Mg^(2+)/Sr^(2+)/Si(>80%),as well as significantly mitigate membrane scaling during *** softened ROC and raw ROC corresponded to a maximum water recovery of 86%and 54%,*** cyclic FO tests(4×10 h),a 27%decline in the water flux was observed for raw ROC,whereas only 4%was observed for softened *** cleaning efficiency using EDTA was also found to be considerably higher for softened ROC(88.5%)than that for raw ROC(49.0%).In addition,CaCO3(92.2%purity)was recovered from the softening sludge with an average yield of 5.6 kg/m^(3) treated *** study provides a proof-of-concept demonstration of the FO-CS coupling process for ROC volume minimization and valuable resources recovery,which makes the treatment of CCI ROC more efficient and more economical.

关键词： Coal chemical industry Forward osmosis Chemical softening Reverse osmosis concentrate

Exploring the formation potential and optical properties of secondary organic aerosol from the photooxidation of selected short aliphatic ethers

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Journal of environmental Sciences 2020年第9期32卷 82-90页

作者： Jianqiang Zhu Jianlong Li Lin Du environment Research institute Shandong UniversityQingdao 266237China

Secondary organic aerosol(SOA)formation potential for six kinds of short aliphatic ethers has been *** size distribution,mass concentration,and yield of SOA formed by ethers photooxidation were determined under different *** results showed that all six ethers can generate SOA via reaction with OH radicals even under no seed and NOxfree *** mass concentration for six seedless experiments was less than 10μg/m3 and the SOA yields were all below 1%.The strong increase in the SOA formation was observed when the system contained ammonium sulfate seed particles,while SOA yield decreased under the high-NOx *** composition was analyzed using offline *** spectra indicated that there are complex components in the particle-phase including carbonyls acid and aldehydes ***,the aqueous filter extracts were analyzed using ultraviolet-visible spectrometer and fluorescence *** the fresh methyl n-butyl ether SOA,the largest absorption peak occurs at 280 nm and there exists slightly absorption in the 300-400 ***-emission matrices display the distinct peak at excitation/emission=470 nm/480 nm according to the fluorescence *** findings are important considerations of formation for ether SOA that can eventually be included in atmospheric models.

关键词： aerosol photooxidation potential

Role of water on the H-abstraction from methanol by ClO

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Journal of environmental Sciences 2018年第9期30卷 89-98页

作者： Shanshan Tang Narcisse T.Tsona Junyao Li Lin Du environment Research institute Shandong University Jinan 250100 China

The influence of a single water molecule on the reaction mechanism and kinetics of hydrogen abstraction from methanol （CH3OH） by the CIO radical has been investigated using ab initio calculations. The reaction proceeds through two channels： abstraction of the hydroxyl H-atom and methyl H-atom of CH30H by CIO, leading to the formation of CH30 ＋ HOC1 （＋H20） and CH20H ＋ HOC1 （＋ H20）, respectively. In both cases, pre- and post-reactive complexes were located at the entrance and exit channel on the potential energy surfaces. Results indicate that the formation of CH2OH ＋ HOC1 （＋H20） is predominant over the formation of CH30 ＋ HOC1 （＋H20）, with ambient rate constants of 3.07 x 10^-19 and 3.01 x 10^-23 cm^3/（***）, respectively, for the reaction without water. Over the temperature range 216.7-298.2 K, the presence of water is seen to effectively lower the rate constants for the most favorable pathways by 4-6 orders of magnitude in both cases. It is therefore concluded that water plays an inhibitive role on the CH30H ＋ ClO reaction under tropospheric conditions.

关键词： Radical-molecule complex H-abstraction reaction Reaction rate constants Quantum chemical calculations

Effects of ionic strength and temperature on the aggregation and deposition of multi-walled carbon nanotubes

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Journal of environmental Sciences 2017年第1期29卷 248-255页

作者： Lixin Wang Xuezhi Yang Qi Wang Yuxuan Zeng Lei Ding Wei Jiang environment Research institute Shandong UniversityJinan 250100China

The aggregation and deposition of carbon nanotubes（CNTs） determines their transport and fate in natural ***,the aggregation kinetics of humic-acid treated multi-walled carbon nanotubes（HA-MWCNTs） was investigated by time-resolved dynamic light scattering in NaCl and CaCl_2 electrolyte *** ionic strength induced HA-MWCNT aggregation due to the less negative zeta potential and the reduced electrostatic *** critical coagulation concentration（CCC） values of HA-MWCNTs were 80 mmol/L in NaCl and 1.3 mmol/L in CaCl_2 electrolyte,showing that Ca^（2＋） causes more serious aggregation than Na~＋.The aggregation behavior of HA-MWCNTs was consistent with Derjaguin-Landau-Verwey-Overbeek *** deposition kinetics of HA-MWCNTs was measured by the optical absorbance at 800 *** critical deposition concentrations for HA-MWCNT in NaCl and CaCl_2 solutions were close to the CCC values,therefore the rate of deposition cannot be increased by changing the ionic strength in the diffusion-limited aggregation *** deposition process was correlated to the aggregation since larger aggregates increased gravitational deposition and decreased random Brownian ***-MWCNTs hydrodynamic diameters were evaluated at 5,15 and 25℃.Higher temperature caused faster aggregation due to the reduced electrostatic repulsion and increased random Brownian motion and collision ***-MWCNTs aggregate faster at higher temperature in either NaCl or CaCl_2electrolyte due to the decreased electrostatic repulsion and increased random Brownian *** results suggest that CNT aggregation and deposition are two correlated processes governed by the electrolyte,and CNT transport is favored at low ionic strength and low temperature.

关键词： Carbon nanotubes Aggregation Deposition Electrolyte Temperature

Effect of oxide nanoparticles on the morphology and fluidity of phospholipid membranes and the role of hydrogen bonds

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Journal of environmental Sciences 2017年第7期29卷 221-230页

作者： Xiaoran Wei Junchao Yu Lei Ding Jingtian Hu Wei Jiang environment Research institute Shandong UniversityJinan 250100China

Engineered oxide nanoparticles（NPs） are widely applied in insulators,catalyzers,paints,cosmetic products,textiles and *** attachment on cell membrane may lead to *** effects of Al_2O_3,Fe_2O_3,SiO_2,TiO_2and ZnO NPs on membrane integrity and fluidity were studied using giant or small unilamellar vesicles in this ***_2O_3 and SiO_2NPs disrupted the oppositely charged membrane,indicating the important role of electrostatic ***,Fe_2O_3,TiO_2and ZnO NPs did not cause serious membrane disruption as Al_2O_3 and SiO_2 *** fluidity was evaluated by the generalized polarity（GP） values of Laurdan fluorescent ***_2 NPs induce the membrane gelation of both positively and negatively charged ***_2O_3 and ZnO NPs induced the gelation of the oppositely charged membrane,but did not cause obvious membrane gelation to the like charged *** phospholipid molecular structural changes after NP exposure were analyzed by Fourier transform infrared（FT-IR） ***-IR spectra revealed the hydrogen bond formation between NPs and the carbonyl/phosphate groups of ***_2O_3 and SiO_2 NPs showed strongest evidence of hydrogen bonding on their FT-IR *** was consistent with the microscopic observation and fluorescent data that Al_2O_3 and SiO_2 NPs caused more serious membrane disruption and *** study on membrane damage provides further knowledge on the cytotoxicity of nanomaterials and the safety of NP application.

关键词： Oxide nanoparticle Membrane disruption Membrane fluidity Vesicles Infrared spectroscopy