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Prediction model on hydrolysis kinetics of phthalate monoester:A density functional theory study

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Journal of Environmental Sciences 2024年第1期135卷 51-58页

作者： Tong Xu Jingwen Chen Deming Xia Weihao Tang Jiansheng Cui Chun Liu Shuangjiang Li College of Environmental Science and Engineering Hebei University of Science and TechnologyShijiazhuang 050000China Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education) School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and ManagementInstitute of Eco-environmental and Soil SciencesGuangdong Academy of SciencesGuangzhou 510650China

As primary degradation products of phthalate esters,phthalate monoesters(MPEs)have been widely detected in various aquatic environments and drawn growing toxicological concerns.Hydrolysis kinetics that is of importance for assessing environmental persistence of chemicals remain elusive for MPEs.Herein,kinetics of base-catalyzed and neutral hydrolysis for 18 MPEs with different leaving groups was investigated by density functional theory calculation.Results indicate that MPEs with leaving groups having p Kaof<10 prefer dissociative transition states.MPEs are more persistent than their parents,and their hydrolysis half-lives were calculated to vary from 3.4 min to 79.2 years(p H=7–9).A quantitative structure-activity relationship model was developed for predicting the hydrolysis kinetics parameters.It was found that p Kaof the leaving groups and electronegativity of the MPEs are key factors determining the hydrolysis kinetics.This work may lay a theoretical foundation for better understanding the chemical process that governs MPE persistence in aquatic environments.

关键词： Phthalate monoesters Phthalate esters Hydrolysis density functional theory Quantitative structure-activity relationship

Amino acids modified nanoscale zero-valent iron:density functional theory calculations,experimental synthesis and application in the Fenton-like degradation of organic solvents

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Journal of Environmental Sciences 2024年第1期135卷 296-309页

作者： Xingchen Yang Fucheng Ming Jianlong Wang Lejin Xu Department of Nuclear Engineering and Technology School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China China-EU Institute for Clean and Renewable Energy Huazhong University of Science and TechnologyWuhan 430074China Institute of Nuclear and New Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Radioactive Wastes Treatment Tsinghua UniversityBeijing 100084China

To improve the adsorption and catalytic performance of heterogeneous Fenton-like catalysts for oil wastes,amino acids were used to modify nanoscale zero-valent iron(AA@Fe^(0)),which were applied in the Fenton-like degradation of organic solvents(tributyl phosphate and n-dodecane,named TBP and DD).Twelve amino acids,i.e.,glycine(Gly),alanine(Ala),leucine(Leu),proline(Pro),phenylalanine(Phe),methionine(Met),cysteine(Cys),asparagine(Asn),serine(Ser),glutamic acid(Glu),lysine(Lys)and arginine(Arg),were selected and calculated by density functional theory(DFT).The optimized structure,charge distribution,the highest occupied molecular orbital(HOMO),the lowest unoccupied molecular orbital(LUMO),interaction region indicator(IRI)isosurface map and adsorption energy of AA@Fe^(0),AA@Fe^(0)-TBP and AA@Fe^(0)-DD were studied,which indicated that Fe is more likely to approach and charge transfer with-COO and-NH_(3) on theα-carbon of amino acids.There is strong attraction between Fe and–COO,and Van der Waals force between Fe and-NH_(3),respectively.In the interaction of AA@Fe^(0)with TBP and DD,Van der Waal force plays an important role.AA@Fe^(0)was synthesized in laboratory and characterized to investigate physicochemical properties.In Fenton-like degradation of organic solvents,the change of COD in water phase during the degradation process as well as the volume of the organic phase after the reaction were investigated.The results of calculations combined with experiments showed that Ser-modified Fe^(0)performed the best in these amino acids,with 98%removal of organic solvents.A possible catalytic mechanism was proposed in which amino acids acted a linking role between Fe and organic solvents,activating H_(2)O_(2)to generate hydroxyl radicals for the degradation of organic solvents.

关键词： Amino acids Nanoscale zero-valent iron density functional theory Organic solvents Fenton-like degradation

Local thermal conductivity of inhomogeneous nano-fluidic films:A density functional theory perspective

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Chinese Physics B 2024年第4期33卷 594-603页

作者：孙宗利康艳霜康艳梅 Department of Mathematics and Physics North China Electric Power UniversityBaoding 071003China College of Science Hebei Agricultural UniversityBaoding 071001China Hebei Key Laboratory of Physics and Energy Technology Baoding 071003China University of International Relations Beijing 100091China

Combining the mean field Pozhar-Gubbins(PG)theory and the weighted density approximation,a novel method for local thermal conductivity of inhomogeneous fluids is proposed.The correlation effect that is beyond the mean field treatment is taken into account by the simulation-based empirical correlations.The application of this method to confined argon in slit pore shows that its prediction agrees well with the simulation results,and that it performs better than the original PG theory as well as the local averaged density model(LADM).In its further application to the nano-fluidic films,the influences of fluid parameters and pore parameters on the thermal conductivity are calculated and investigated.It is found that both the local thermal conductivity and the overall thermal conductivity can be significantly modulated by these parameters.Specifically,in the supercritical states,the thermal conductivity of the confined fluid shows positive correlation to the bulk density as well as the temperature.However,when the bulk density is small,the thermal conductivity exhibits a decrease-increase transition as the temperature is increased.This is also the case in which the temperature is low.In fact,the decrease-increase transition in both the small-bulk-density and low-temperature cases arises from the capillary condensation in the pore.Furthermore,smaller pore width and/or stronger adsorption potential can raise the critical temperature for condensation,and then are beneficial to the enhancement of the thermal conductivity.These modulation behaviors of the local thermal conductivity lead immediately to the significant difference of the overall thermal conductivity in different phase regions.

关键词： thermal conductivity nano-fluidic films density functional theory

Sensitivity impacts owing to the variations in the type of zero-range pairing forces on the fission properties using the density functional theory

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Nuclear Science and Techniques 2024年第3期35卷 198-207页

作者： Yang Su Ze-Yu Li Li-Le Liu Guo-Xiang Dong Xiao-Bao Wang Yong-Jing Chen China Nuclear Data Center China Institute of Atomic EnergyBeijing 102413China School of Science Huzhou UniversityHuzhou 313000China

Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov approximation.Variations in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and discussed.The fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap approximation.The results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing force.Based on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data.

关键词： Nuclear fission density functional theory Pairing force Potential energy surfaces Fission fragment distribution

density functional theory for selecting modifiers for enhanced adsorption of tetracycline in water by biochar

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Waste Disposal and Sustainable Energy 2023年第1期5卷 25-35页

作者： Sayeda Ummeh Masrura Tauqeer Abbas Hamed Heidari Shams Razzak Rothee Ahsan Javed Eakalak Khan Department of Civil and Environmental Engineering and Construction University of NevadaLas Vegas4505 S.Maryland ParkwayBox 454015Las VegasNV89154-4015USA Department of Chemistry and Chemical Engineering Lahore University of Management SciencesLahorePakistan

Antibiotics and their metabolic byproducts are found in wastewater and natural water as a result of increased consumption,posing a major threat to humans and other living organisms.One of the most promising methods for their removal is adsorption using biochar because it offers excellent adsorption potential and is both affordable and environmentally beneficial.However,raw biochar frequently has a low adsorption capacity due to its limited pore structure and unfavorable surface characteristics.Biochar surface modifications using modifiers such as H3PO4,KOH,and NaOH have improved the surface area and thereby the adsorption capacity.Experimental methods for assessing the effectiveness and adsorption mechanism of modified biochar are costly and time-consuming.density functional theory(DFT)was used to investigate the interfacial interactions and adsorption mechanism of tetracycline(TC),a widely used antibiotic for personal care and veterinary medication,on unmodified and modified biochar.The DFT calculations showed that the adsorption energy of TC on unmodified and modified biochar is in the following order:KOH-modified biochar(−2.38 eV)

关键词： Tetracycline adsorption Modified biochar density functional theory Adsorption energy Modifier screening

density functional theory for Electrocatalysis

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Energy & Environmental Materials 2022年第1期5卷 157-185页

作者： Xiaobin Liao Ruihu Lu Lixue Xia Qian Liu Huan Wang Kristin Zhao Zhaoyang Wang Yan Zhao State Key Laboratory of Silicate Materials for Architectures International School of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China Zhejiang University Hangzhou 310058China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Center of Smart Materials and DevicesSchool of Materials Science and EngineeringWuhan University of TechnologyWuhan 430070China Lynbrook High School San Jose CA 95129USA The Institute of Technological Sciences Wuhan UniversityWuhan 430072China

It is a considerably promising strategy to produce fuels and high-value chemicals through an electrochemical conversion process in the green and sustainable energy systems.Catalysts for electrocatalytic reactions,including hydrogen evolution reaction(HER),oxygen evolution reaction(OER),oxygen reduction reaction(ORR),nitrogen reduction reaction(NRR),carbon dioxide reduction reaction(CO_(2)RR),play a significant role in the advanced energy conversion technologies,such as water splitting devices,fuel cells,and rechargeable metal-air batteries.Developing low-cost and highly efficient electrocatalysts is closely related to establishing the composition-structure-activity relationships and fundamental understanding of catalytic mechanisms.density functional theory(DFT)is emerging as an important computational tool that can provide insights into the relationship between the electrochemical performances and physical/chemical properties of catalysts.This article presents a review on the progress of the DFT,and the computational simulations,within the framework of DFT,for the electrocatalytic processes,as well as the computational designs and virtual screenings of new electrocatalysts.Some useful descriptors and analysis tools for evaluating the electrocatalytic performances are highlighted,including formation energies,d-band model,scaling relation,egorbital occupation,and free energies of adsorption.Furthermore,the remaining questions and perspectives for the development of DFT for electrocatalysis are also proposed.

关键词： analysis tools density functional theory descriptors electrocatalysis

density functional theory Study of Marine Polybrominated Diphenyl Ethers in Anaerobic Degradation

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中国海洋大学学报:英文版 2023年第5期22卷 1353-1360页

作者： XU Xiang MAN Miaomiao SUN Qinxing LIU Qingzhi WU Kechen YANG Dengfeng College of Chemistry and Pharmaceutical Sciences Qingdao Agricultural UniversityQingdao 266109China Fujian Key Laboratory of functional Marine Sensing Materials Minjiang UniversityFuzhou 350108China

Polybrominated diphenyl ethers(PBDEs)are a kind of serious pollutants in the ocean.Biodegradation is considered as an economical and safe way for PBDEs removal and reductive debromination dominates the initial pathway of anaerobic degradation.On the basis of experimental study,Octa-BDE 197,Hepta-BDE 183,Hexa-BDE 153,Penta-BDE 99 and Tetra-BDE 47 were selected as the initial degradation objects,and their debromination degradation were studied using density functional theory.The structures were optimized by Gaussian 09 program.Furthermore,the molecular orbitals and charge distribution were analyzed.All C-Br bond dissociation energies at different positions including ortho,meta and para bromine atoms were calculated and the sequence of debromination was obtained.There is a close relationship between molecular structure,charge,molecular orbital and C-Br bond.All PBDEs exhibited similar debromination pathways with preferential removal of meta and para bromines.

关键词： polybrominated diphenyl ethers reductive debromination anaerobic degradation density functional theory bond dissociation energies

Effect of rare earth on physical properties of Na_(0.5)Bi_(0.5)TiO_(3)system:A density functional theory investigation

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Journal of Rare Earths 2022年第3期40卷 473-481,I0005页

作者： Manal Benyoussef Halima Zaari Jamal Belhadi Youssef El Amraoui Hamid Ez-Zahraouy Abdelilah Lahmar Mimoun El Marssi Laboratory of Physics of Condensed Matter(LPMC) University of Picardie Jules VerneScientific Pole80039Amiens Cedex 1France Laboratory of Condensed Matter and Indisciplinary Science(LaMCScI) Faculty of ScienceMohammed V UniversityBP 1014RabatMorocco National School of Arts and Crafts Moulay Ismail University50500MeknesMorocco

Na_(0.5)(Bi_(3/4)RE_(1/4))_(0.5)TiO_(3)(RENBT,RE=Nd,Gd,Dy,and Ho)compounds were investigated in the framework of first-principles calculations using the full potential linearized augmented plane wave(FP-LAPW)method based on the spin-polarized density functional theory implemented in the WIEN2k code.Combined charge density distribution and Ti K-edge X-ray absorption spectra reveal that the RENBT compositions with high polarization values are accompanied by a higher TiO_(6)distortion,DyNBT,and NdNBT compounds.The effect of the rare-earth elements on the polarization is confirmed experimentally with the collection of the hysteresis loops.The investigation of the electronic properties of the compounds highlights the emergence of a magnetization owing to the 4f orbital effect of the rare-earth elements.Besides,the investigation of the chemical ordering shows a short-range chemical ordering for the pure composition and an increased A-site disorder for dysprosium doped NBT system.The increased disorder may speak for increased relaxor properties in the RE doped compositions.

关键词： density functional theory Sodium bismuth titanate Rare earths A-site ordering Ferroelectric properties Magnetization

Investigation of the structural, electronic and mechanical properties of CaO–SiO_(2) compound particles in steel based on density functional theory

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International Journal of Minerals,Metallurgy and Materials 2023年第4期30卷 744-755页

作者： Chao Gu Ziyu Lyu Qin Hu Yanping Bao State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China

CaO–SiO_(2)compounds compromise one of the most common series of oxide particles in liquid steels, which could significantly affect the service performance of the steels as crack initiation sites. However, the structural, electronic, and mechanical properties of the compounds in CaO–SiO_(2)system are still not fully clarified due to the difficulties in the experiments. In this study, a thorough investigation of these properties of CaO–SiO_(2)compound particles in steels was conducted based on first-principles density functional theory. Corresponding phases were determined by thermodynamic calculation, including gamma dicalcium silicate(γ-C2S), alpha-prime(L) dicalcium silicate(αL′-C2S), alpha-prime(H) dicalcium silicate(αH′-C2S), alpha dicalcium silicate(α-C2S), rankinite(C3S2), hatrurite(C3S), wollastonite(CS), and pseudowollastonite(Ps-CS). The results showed that the calculated crystal structures of the eight phases agree well with the experimental results. All the eight phases are stable according to the calculated formation energies, and γ-C2S is the most stable. O atom contributes the most to the reactivity of these phases. The Young’s modulus of the eight phases is in the range of 100.63–132.04 GPa. Poisson’s ratio is in the range of0.249–0.281. This study provided further understanding concerning the CaO–SiO_(2)compound particles in steels and fulfilled the corresponding property database, paving the way for inclusion engineering and design in terms of fracture-resistant steels.

关键词： CaO–SiO_(2) density functional theory structural property electronic property mechanical property