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Toxicity mechanisms of photodegraded polyvinyl chloride nanoplastics on pea seedlings

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Frontiers of Environmental Science & Engineering 2024年第4期18卷 111-124页

作者： hao Wu Beibei He Bocheng Chen An liu College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Nanoplasctics(NPs),which are very small in particle size,exert toxic effect to ***,compared to original NPs,photodegraded NPs would pose higher *** is because their relatively higher specific surface areas and the presence of additives which can more easily *** original NPs and aged NPs affect plant growth has not been widely *** work chose polyvinyl chloride NPs(PVC-NPs)that were subjected to up to 1000 h UV light radiation to explore the impact of PVC-NPs on the growth of pea seedlings(Pisum Sativum L.).The results indicated the existence of PVC-NPs with longer UV light radiation time and higher concentrations had more negative influences on pea seedlings’growth such as germination rate(decreased by 10.6%–22.5%),stem length(decreased by 2.8%–8.1%),dry weight(decreased by 6.3%–7.1%)and fresh weight(decreased by 6.7%–14.8%).It was also noted that photodegraded PVC-NPs resulted in damage to leaf stomata and roots,hindering photosynthesis and absorption of nutrients and hence the decrease in chlorophyll and soluble sugar *** to transcriptomic investigation results,the presence of aged PVC-NPs primarily influenced protein processing in endoplasmic reticulum(upregulated metabolic pathway)and phenylpropanoid biosynthesis(downregulated metabolic pathway)of pea *** results provide an in-depth understanding of how NPs influence the growth of plants.

关键词： Nanoplasctics Polyvinyl chloride Toxicity mechanisms Plant growth

Hydrochemical Characterization,Controlling Factors and Water Quality of Surface Water in Shandong Province,North China

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Journal of Earth Science 2024年第1期35卷 155-166页

作者： ran An Jiutan liu Zongjun Gao Changsuo Li Yuming Peng School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China 801 Institute of Hydrogeology and Engineering Geology Shandong Provincial Bureau of Geology&Mineral ResourcesJinan 250014China Key Laboratory of Groundwater Resources and Environment Shandong Provincial Bureau of Geology&Mineral ResourcesJinan 250014China Shandong Engineering Research Center for Groundwater Environmental Protection and Remediation Jinan 250014China

In this study,90 surface water samples were collected from Shandong Province(SDP)in the dry and wet seasons and analyzed using statistical analysis,hydrochemical methods and water quality index(WQI).The content of main ions showed seasonal variations,with a higher average value in the dry season than in the wet *** points exhibiting high contents of the main chemical components were mainly distributed in areas southwest of SDP,north of Weifang,and around *** saturation index of carbonate minerals was greater than zero,while that of evaporite minerals was less than *** hydrochemical characteristics of surface water are mainly dominated by rock weathering as well as cation *** addition,surface water in SDP has significantly been affected by anthropogenic *** of the surface water could be classified as weakly alkaline soft-fresh water,with the hydrochemical types of SO_(4)·Cl-Ca·Mg and SO_(4)·*** terms of WQI,47.88% and 37.88% of the water samples in SDP were classified as poor water in the dry and wet seasons,*** the whole,the water quality is higher in the wet season than in the dry season,and surface water in SDP is generally suitable for agricultural irrigation.

关键词： surface water hydrochemical characteristics controlling factors water quality Shandong Province

Relationship between the Stratospheric Arctic Vortex and Surface Air Temperature in the Midlatitudes of the Northern Hemisphere

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Journal of Meteorological Research 2024年第1期38卷 39-52页

作者： Xue ran Dingzhu HU Yang ZHANG Mei-Chen liu Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044 School of Atmospheric Sciences Nanjing UniversityNanjing 210023

It is known that different relationships exist between the strength and displacement of the stratospheric polar vortex(SPV),and the surface air temperature(SAT)patterns in Eurasia and North America,but the mechanisms behind these relationships remain unclear,especially on an interannual *** on empirical orthogonal function(EOF)analysis using NCEP reanalysis data over 1958–2018,this study attempts to ascertain the relationship between the SPV intensity and displacement over the Arctic and the SATs in the midlatitudes of the Northern *** results indicate that a strengthened SPV corresponds to an SAT increase in Eurasia and a decrease in eastern North America and *** the SPV is shifted towards Eurasia,however,a corresponding SAT increase occurs in both North America and Eurasia,with a larger increase in North America than in ***,a strengthened SPV tends to correspond to a positive North Atlantic Oscillation-like circulation in the troposphere with negative geopotential height(GH)anomalies in Greenland and eastern North American continent and positive GH anomalies to the north of 45°N in Eurasia,which corresponds to lower SATs in North America than in ***,when the SPV shifted towards Eurasia,it was accompanied by a positive Pacific/North American-like pattern with a deepened Aleutian low,which corresponds to the increasing SATs in North *** tropospheric circulation changes are related to the response of tropospheric planetary wave activity to the SPV.A strengthened SPV corresponds to the weakening of tropospheric planetary wave-1 waves,which is accompanied by a negative GH in North America but a positive GH in *** the SPV shifted towards Eurasia,the tropospheric planetary wave-1(-2)waves strengthened(weakened),and the combined effects of the planetary wave-1 and wave-2 waves would cause positive GH anomalies in both Eurasia and North America.

关键词： stratospheric polar vortex surface air temperature teleconnection patterns planetary waves

Novel Sum-of-Sinusoids Simulation Channel Modeling for 6G Multiple-Input Multiple-Output Vehicle-to-Everything Communications

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China Communications 2024年第1期21卷 242-259页

作者： hao Jiang Hongming Zhang Ting liu College of Artificial Intelligence Nanjing University of Information Science and Technology210044China National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China School of Information and Communication Engineering Beijing University of Posts and TelecommunicationsChina

In this paper,a statistical cluster-based simulation channel model with a finite number of sinusoids is proposed for depicting the multiple-input multiple-output(MIMO)communications in vehicleto-everything(V2X)*** the proposed sum-of-sinusoids(SoS)channel model,the waves that emerge from the transmitter undergo line-of-sight(LoS)and non-line-of-sight(NLoS)propagation to the receiver,which makes the model suitable for describing numerous V2X wireless communication scenarios for sixth-generation(6G).We derive expressions for the real and imaginary parts of the complex channel impulse response(CIR),which characterize the physical propagation characteristics of V2X wireless *** statistical properties of the real and imaginary parts of the complex CIRs,i.e.,autocorrelation functions(ACFs),Doppler power spectral densities(PSDs),cross-correlation functions(CCFs),and variances of ACFs and CCFs,are derived and *** results are generated and match those predicted by the underlying theory,demonstrating the accuracy of our derivation and *** proposed framework and underlying theory arise as an efficient tool to investigate the statistical properties of 6G MIMO V2X communication systems.

关键词： complex CIRs LoS and NLoS propagation components MIMO V2X communication environments SoS simulation channel model statistical properties

Experimental Investigation and X-Ray Computed Microtomography Simulation on Thermal Physical Properties of Foundation Materials after Molten Salt Leakage in the Storage Tank

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Journal of Thermal Science 2024年第2期33卷 591-601页

作者： WANG Zhaowen ZHOU hao LUO Jiawei LI Yawei FANG hao liu Tianxiao State Key Laboratory of Clean Energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou310027China

This paper studied the thermal physical properties of foundation materials in the molten salt tank of thermal energy storage system after molten salt leakage by Transient plane source experiment and X-ray computed microtomography simulation *** microstructure,thermal properties and pressure resistance with different particle diameters were *** measured heat conductivities from Transient plane source experiment for three cases are 0.49 W/(m·K),0.48 W/(m·K),and 0.51 W/(m·K),and the porosity is 30.1%,30.7%,and 31.2% *** heat conductivity simulating results of three cases are 0.471 W/(m·K),0.482W/(m·K),and 0.513 W/(m·K).The ratio of difference between the results of simulation and Transient plane source measurement is as low as 1.2%,verifying the reliability of experimental and simulation results to a certain *** with the heat conductivity of 0.097-0.129 W/(m·K) and porosity of 71.6%-78.9% without leaking salt,the porosity is reduced by more than 50% while the heat conductivity increased by 4 to 5 times after molten salt *** significant increase in heat conductivity has a great impact on security operation,structure design,and modeling of the tank foundation for solar power plants.

关键词： heat conductivity X-ray computed microtomography foundation materials three-phase threshold algorithm molten salt leakage

A Degree Condition for Graphs Having All(a,b)-parity Factors

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 656-664页

作者： hao-dong liu Hong-liang LU School of Mathematics and Statistics Xi'an Jiaotong UniversityXi'an 710049China

Let a and b be positive integers such that a≤b and a≡b(mod 2).We say that G has all(a,b)-parity factors if G has an h-factor for every function h:V(G)→{a,a+2,…,b-2,b} with b|V(G)| even and h(v)≡b(mod 2) for all v∈V(G).In this paper,we prove that every graph G with n≥2(b+1)(a+b) vertices has all(a,b)-parity factors if δ(G)≥(b^(2)-b)/a,and for any two nonadjacent vertices u,v ∈V(G),max{d_(G)(u),d_(G)(v)}≥bn/a+***,we show that this result is best possible in some sense.

关键词： degree condition all(a,b)-factors

Solidification/Stabilization of Chromium in Red Mud-based Geopolymer

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 819-830页

作者：田崇霏 LUO Zhongtao liu Lei liu Xiaohai 张美香陈萌 HAI ran School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China Henan Renbang Technology Co. Ltd.Luoyang 471700China School of Water Conservancy and Civil Engineering Zhengzhou UniversityZhengzhou 450001China School of Architectural and Civil Engineering Zhongyuan University of TechnologyZhengzhou 450007China

Up to 1.5wt%of Cr(Ⅲ)salts(CrCl_(3),and Cr_(2)O_(3))and Cr(Ⅵ)salts(Na_(2)CrO_(4),and CaCr_(2)O_(7))were incorporated into red mud-based geopolymers,*** solidification/stabilization,compressive strength,and durability of the Cr-containing geopolymers were *** experimental results indicate that the red mud-based geopolymer could effectively solidify/stabilize different types of Cr salts with solidification/stabilization rates of above 99.61%.Geopolymers are environmentally safe when the dosage of CaCr_(2)O_(7)is≤1.0wt%,or the dosage of CrCl_(3),Cr_(2)O_(3),and Na_(2)CrO_(4)is≤1.5wt%,*** effects of Cr salts on the compressive strength varies with the type and content of Cr *** freeze-thaw cycle is more destructive to geopolymer properties than sulfate attack or acid rain *** solidification/stabilization of Cr is mainly attributed to the following reasons:a)The chemical binding of Cr is related to the formation of Cr-containing hydrates(eg,magnesiochromite((Mg,Fe)(Cr,Al)_(2)O_(4)))and doping into N-A-S-H gel and C-A-S-H gel framework;b)The physical effect is related to the encapsulation by the hydration products(e g,N-A-S-H gel and C-A-S-H gel).This study provides a reference for the treatment of hazardous Cr-containing wastes by solid waste-based geopolymers.

关键词： chromium solidification/stabilization geopolymer red mud durability

Advances in self-assembly-based circularly polarized luminescent materials

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Science China Chemistry 2024年第10期67卷 3247-3257页

作者： Bing-hao liu Yang Zong Na liu Zong-Quan Wu State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China The School of Pharmaceutical Sciences Jilin UniversityChangchun 130021China

Circularly polarized luminescent(CPL)materials have garnered attention for their diverse applications,including three-dimensional(3D)imaging,bio-imaging,chiral sensing,and other emerging ***,the fabrication of CPL-activated materials required the use of chiral luminescent small *** introduction of the idea of self-assembly has transformed the production of CPL-activated materials,providing new and promising opportunities for their *** utilizing self-assembly,it is now feasible to produce chiral nano-assemblies with CPL activity not only from chiral molecules but also from non-chiral substances and inorganic *** addition,self-assembly routes provide a way to increase the asymmetry factor,creating possibilities for additional refinement and adjustment of CPL material *** review offers a summary of the current progress and developments in the self-assembly of small molecules and polymers,with a specific emphasis on their capacity to create or enhance CPL in different *** aim of this review is to inspire interest in optical materials that are based on the principles of self-assembly.

关键词： circularly polarized luminescence photochemistry self-assembly chiral materials

Process synthesis for the separation of coal-to-ethanol products

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Chinese Journal of Chemical Engineering 2024年第5期69卷 263-278页

作者： Qingping Qu Daoyan liu hao Lyu Jinsheng Sun School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Sustainable Energy and Environment Thrust The Hong Kong University of Science and Technology(Guangzhou)Nansha 511400China

The coal-to-ethanol process,as the clean coal utilization,faces challenges from the energy-intensive distillation that separates multi-component effluents for pure *** to at least eight columns,the synthesis of the ethanol distillation system is impracticable for exhaustive comparison and difficult for conventional superstructure-based optimization as rigorous models are *** work adopts a superstructure-based framework,which combines the strategy that adaptively selects branches of the state-equipment network and the parallel stochastic algorithm for process ***-performance computing significantly reduces time consumption,and the adaptive strategy substantially lowers the complexity of the superstructure ***,parallel computing,elite search,population redistribution,and retention strategies for irrelevant parameters are used to improve the optimization efficiency *** optimization terminates after 3000 generations,providing a flowsheet solution that applies two non-sharp splitting options in its distillation *** a result,the 59-dimension superstructure-based optimization was solved efficiently via a differential evolution algorithm,and a high-quality solution with a 28.34%lower total annual cost than the benchmark was ***,the solution of the superstructure-based optimization is comparable to that obtained by optimizing a single specific configuration one by *** indicates that the superstructure-based optimization that combines the adaptive strategy can be a promising approach to handling the process synthesis of large-scale and complex chemical processes.

关键词： Coal-to-ethanol Process synthesis Superstructure-based optimization Differential evolution algorithm Distillation