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Analysis and optimization of performance parameters of the 220Rn chamber in flow-field mode using computational fluid dynamics method

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Nuclear Science and Techniques 2024年第10期35卷 130-145页

作者： Shao-Hua Hu Yong-Jun Ye Zheng-Zhong He De-Tao Xiao Xiang-Yu Xu Jian-Kai Wang Qing-Zhi Zhou school of Nuclear Science and Technology University of South China school of resources environment and Safety engineering University of South China

The impact of the radiation dose produced by222Rn/220Rn and its progeny on human health has garnered increasing interest in the nuclear research field. The establishment of robust, regulatory, and competent220Rn chambers is crucial for accurately measuring radioactivity levels. However, studying the uniformity of the220Rn progeny through experimental methods is challenging, because measuring the concentration of220Rn and its progeny in multiple spatial locations simultaneously and in real time using experimental methods is difficult. Therefore, achieving precise control of the concentration of220Rn and its progeny as well as the reliable sampling of the progeny pose significant challenges. To solve this problem, this study uses computational fluid dynamics to obtain the flow-field data of the220Rn chamber under different wind speeds and progenyreplenishment rates. Qualitative analysis of the concentration distribution of the progeny and quantitative analysis of the progeny concentration and uniformity of the progeny concentration are conducted. The research findings indicated that the progeny concentration level is primarily influenced by wind speed and the progeny-complement rate. Wind speed also plays a crucial role in determining progeny concentration uniformity, whereas the progeny-complement rate has minimal impact on uniformity. To ensure the accuracy of220Rn progeny concentration sampling, we propose a methodology for selecting an appropriate sampling area based on varying progeny concentrations. This study holds immense importance for enhancing the regulation and measurement standards of220Rn and its progeny.

关键词： CFD simulation Progeny Regulatory Thoron

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Co-incorporation of Chinese milk vetch(Astragalus sinicus L.)and chemical fertilizers alters microbial functional genes supporting short-time scale positive nitrogen priming effects in paddy soils

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Pedosphere 2024年第3期34卷 567-576页

作者： Limin WANG Chunmei HE Dongfeng HUANG Juhua YU Cailing LIU Qinghua LI Yibin HUANG Juan LI Fei WANG Institute of resources Environment and Soil FertilizerSoil and Fertilizer InstituteFujian Academy of Agricultural SciencesFuzhou 350012(China) school of resources and environment engineering Anhui UniversityHefei 230601(China)

Nitrogen(N)priming is a microbially mediated biochemical process as affected by different incorporation ***,little information is known about the microbial mechanisms driving the response of N priming to co-operation of Chinese milk vetch(CMV,Astragalus sinicus L.)and different rates of chemical fertilizers in paddy soils in South ***,an anaerobic incubation experiment was conducted to study N priming effects(PE)and their relationships with soil microbial functional genes after CMV incorporation alone(M),co-incorporation of CMV with 100%(normal dosage)chemical fertilizers(MC100),and co-incorporation of CMV with 80% chemical fertilizers(MC80).Co-incorporation of CMV and chemical fertilizers enhanced the short-time scale(the first 20 d of incubation)positive PE of N,while no significant differences existed among the three treatments on day 60 or 90 of incubation(P>0.05).Compared with the M treatment,gross priming effect(GPE)in the MC100 and MC80 treatments significantly increased by 34.0% and 31.3%,respectively,and net priming effect(NPE)increased by 47.7% and 47.8%,respectively,during the first 20 d of incubation(P<0.05).This was likely attributed to soil nutrient availability and added substrate *** MC100 and MC80 treatments increased the gdhA gene abundance by 5.0% and 9.8%,increased the gdh2 gene abundance by 12.7% and 45.7%,and increased the nasB gene abundance by 9.5% and 41.4%,respectively,in comparison with the M treatment on day 20 of *** analyses indicated that soil microbial functional genes involved in N mineralization(gdhA and gdh2),assimilatory nitrate reduction(nasB),and nitrification(amoB)were significantly correlated with N priming under different incorporation practices during the incubation period(P<0.05).Thus,co-incorporation of CMV and chemical fertilizers can regulate soil microbial community functional gene structure,which may accelerate mineralization and assimilatory nitrate reduction and inhibit

关键词： green manure gross priming effect incorporation practice microbial mechanism net priming effect rice field soil

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Sn-doped cobalt containing perovskite as the air electrode for highly active and durable reversible protonic ceramic electrochemical cells

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Journal of Advanced Ceramics 2024年第1期13卷 63-72页

作者： Min Fu Wenjing Hu Hua Tong Xin Ling Linggui Tan Fanglin Chen Zetian Tao school of resources Environment and Safety EngineeringUniversity of South ChinaHengyang 421001China Department of Mechanical engineering University of South CarolinaColumbia 29208USA

One potential solution to the problems of energy storage and conversion is the use of reversible protonic ceramic electrochemical cells(R-PCEC),which are based on the solid oxide fuel cell(SOFC)technology and offer a flexible route to the generation of renewable ***,the R-PCEC development faces a range of significant challenges,including slow oxygen reaction kinetics,inadequate durability,and poor round-trip efficiency resulting from the inadequacy of an air *** address these issues,we report novel B-sites doped Pr_(0.5)Ba_(0.5)Co_(0.7)Fe_(0.3)O_(3−δ)(PBCF)with varying amounts of Sn as the air electrode for R-PCEC to further enhance electrochemical performance at lower *** 600℃,R-PCEC with an air electrode consisting of Pr_(0.5)Ba_(0.5)Co_(0.7)Fe_(0.25)Sn_(0.05)O_(3+δ)has achieved peak power density of 1.12 W∙cm^(−2) in the fuel cell mode and current density of 1.79 A∙cm^(−2) in the electrolysis mode at a voltage of 1.3 ***,R-PCECs have shown good stability in the electrolysis mode of 100 *** study presents a practical method for developing durable high-performance air electrodes for R-PCECs.

关键词： triple conducting oxide dual-element doping protonic ceramic electrochemical cells(PCECs) catalytic

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Effectiveness of urban distributed runoff model for discharge and water depth calculation in urban drainage pipe networks

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Journal of Hydrodynamics 2024年第3期36卷 582-591页

作者： Yang Zhou Yi-ling Leng Peng-yu Wang Shang-hong Zhang Yu-long Zhu Yu-jun Yi school of Water resources and Hydropower engineering North China Electric Power UniversityBeijing102206China State Key Laboratory of Water environment Simulation School of EnvironmentBeijing Normal UniversityBeijing100875China

Effective urban land-use re-planning and the strategic arrangement of drainage pipe networks can significantly enhance urban flood defense *** at reducing the potential risks of urban flooding,this paper presents a straightforward and efficient approach to an urban distributed runoff model(UDRM).The model is developed to quantify the discharge and water depth within urban drainage pipe networks under varying rainfall intensities and land-use *** Nash efficiency coefficient of UDRM exceeds 0.9,which indicates its high computational efficiency and potential benefit in predicting urban *** prediction of drainage conditions under both current and re-planned land-use types is achieved by adopting different flood recurrence *** findings reveal that the re-planned land-use strategies could effectively diminish flood risk upstream of the drainage pipe network across 20-year and 50-year flood recurrence ***,in the case of extreme rainfall events(a 100-year flood recurrence),the re-planned land-use approach fell short of fulfilling the requirements necessary for flood disaster *** these instances,the adoption of larger-diameter drainage pipes becomes an essential requisite to satisfy drainage ***,the proposed UDRM effectively combines land-use information with pipeline data to give practical suggestions for pipeline modification and land-use optimization to combat urban ***,this methodology warrants further promotion in the field of urban re-planning.

关键词： Stormwater runoff water depth urban distributed runoff model urban drainage pipe networks urban land-use re-planning

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Protein crystallization with DNA templates

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Particuology 2024年第3期86卷 262-268页

作者： Bo Zhang Jia Yu Zhe Pu Wenhui Guo Ruoqi Yang Yu Wen Zhijiang Rong Hui Wang Xiaoli Wu Bo Wang Hongyan Sun school of environment and resources Taiyuan University of Science and TechnologyTaiyuan030024China school of Chemical engineering and Technology Taiyuan University of Science and TechnologyTaiyuan030024China

Protein crystallization plays a significant role in three-dimensional structural analysis and protein *** is important to increase the crystallization efficiency,which is possible by adding hetero-geneous templates in crystallization *** is biologically compatible and artificially designable polymer,which is easy to *** this study,single-and double-stranded DNA of precise sequences were designed and used as templates to promote protein crystallization of lysozyme and ***-fluence of DNA,single-stranded DNA with 10,20,40 bases and double-stranded DNA with 10,20,40 base pairs,were *** success rate of obtaining crystals of lysozyme and catalase in equal period was significantly improved with the addition of DNA comparing without templates ***-stranded DNA led to higher nucleation rate than that with single-stranded *** promotion of nucleation was more obvious at low concentration of protein solution and with longer chain DNA *** number and crystallization rate was enhanced with addition of long double-stranded DNA *** the results confirm that DNA is an effective polymer additive to enhance protein crystallization,especially for the application of the scarce protein crystallization.

关键词： DNA Polymer Additive Protein Crystallization

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Unveiling the protective role of biofilm formation on the photoaging of microplastics

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Science China Technological Sciences 2024年第10期67卷 3067-3078页

作者： ZHANG HaiYu LIU Peng ZHANG JiaYu DAI JiaMin ZHANG XinRui ZHANG ZiXuan JIA HanZhong Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China Ministry of AgricultureCollege of Natural Resources and EnvironmentNorthwest A&F University Key Laboratory of Organic Compound Pollution Control engineering School of Environmental and Chemical EngineeringShanghai University

In natural water, microplastics（MPs） inevitably undergo microbial colonization to form biofilm, while the effect of biofilm formation on the photoaging of MPs remains unknown. This study systematically investigated the photoaging behavior of disposable box-derived polypropylene（PPMPs） and polystyrene（PSMPs） mediated by formed biofilm in water. After incubating in Weihe water samples for 105 d, the biofilm was validated to form in PPMPs and PSMPs, with higher formation in PSMPs. In particular, biofilm formation inhibited the photoaging of PPMPs and PSMPs, with an 11.1% and 50.6% decrease in photooxidation compared to their virgin counterparts after 20 d of ultraviolet（UV） irradiation. Moreover, the photoaging route of MPs such as the reaction priority of functional groups（e.g., C–H, C=O, and benzene ring） was altered, indicating the important role of biofilm formation in the photoaging process of MPs. The protective effect of the biofilm was mainly caused by the role of optical light filters that absorbed UV energy by sacrificing themselves. Also, as the main attacker on MPs, the production of reactive oxygen species（ROS, mainly1O2and ·OH） was inhibited by biofilm, which was mainly responsible for the decreased photoaging of MPs. This study revealed the important role of biofilm in the photoaging process of MPs and suggested a higher resistance of（micro）plastics in natural water than that in the laboratory using pure MPs, which contributed to a deeper understanding of the environmental fate and pollution of MPs.

关键词： microplastics biofilm photoaging physical shielding reactive oxygen species

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Effects of operating conditions on iron(hydr)oxides evolution and ciprofloxacin degradation in potassium ferrate-ozone stepwise oxidation system

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Journal of environmental Sciences 2024年第1期135卷 367-378页

作者： Xiaochen Li Yifan Wang Ning Wang Mei Li Maomao Bai Jingtao Xu Hongbo Wang school of Municipal and environmental engineering Shandong Jianzhu UniversityJinan 250101China resources and environment Innovation Institute Shandong Jianzhu UniversityJinan 250101China

In this study,a stepwise oxidation system of potassium ferrate(K_(2)FeO_(4))combined with ozone(O+3)was used to degrade ciprofloxacin(CIP).The effects of pH and pre-oxidation time of K_(2)FeO_(4) on the evolution of K_(2)FeO_(4) reduction products(iron(hydr)oxides)and CIP degradation were *** was found that in addition to its own oxidation capacity,K_(2)FeO_(4) can also influence the treatment effect of CIP by changing the catalyst *** presence of iron(hydr)oxides effectively enhanced the mineralization rate of CIP by catalyzing *** pH value can influence the content and types of the components with catalytic ozonation effect in iron(hydr)*** K_(2)FeO_(4) pre-oxidation stage can produce more iron(hydr)oxides with catalytic components for subsequent ozonation,but the evolution of iron(hydr)oxides components was influenced by O_(3) *** can also avoid the waste of oxidation capacity owing to the oxidation of iron(hydr)oxides by O_(3) and free *** intermediate degradation products were identified by Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS).Besides,the degradation pathways were *** the degradation products of CIP,the product with broken quinolone ring structure only appeared in the stepwise oxidation system.

关键词： Potassium ferrate reduction products Catalytic ozonation Ciprofloxacin Potassium ferrate pre-oxidation time

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From ore to MOF: A case of MIL-100(Fe) production from iron ore concentrates

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Progress in Natural Science:Materials International 2024年第01期34卷 66-73页

作者： Miao Chang Chiyao Tang Chong-Chen Wang Chen Zhao Beijing Key Laboratory of Functional Materials for Building Structure and environment Remediation School of Environment and Energy Engineering Beijing University of Civil Engineering and Architecture

Within this work, iron ore concentrates instead of elemental iron Fe0and iron salts like Fe（NO3）3and FeCl3were selected as iron source to prepare MIL-100（Fe）(labeled as MIL-100（Fe）-ore). The corresponding synthesis cost is reduced to half of the MIL-100（Fe） produced from elemental iron and iron salts. As well, the unreacted iron ore concentrates can be easily separated from the as-prepared MIL-100（Fe）-ore by magnetic to facilitate the purification process, free of the strong acids to wash the residual iron. The as-obtained MIL-100（Fe）-ore with Langmuir surface area up to 2281.6 m2g-1displayed long-term chemical stability. Furthermore, the sorption capacity of MIL-100（Fe）-ore towards malachite green（MG） is up to 522.3 mg g-1at 25℃ and initial pH = 3.2, higher than that of MIL-100（Fe） yielded by conventional hydrothermal process. Finally, the production cost and life cycle assessment of MIL-100（Fe）-ore were compared with other traditional production procedures. The results revealed that our work greatly reduced the synthesis cost and enhanced the environmental sustainability.

关键词： Metal-organic framework Iron ore concentrates Adsorption Life cycle assessment

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Stability of water yield in watersheds

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Science China Earth Sciences 2024年第2期67卷 483-496页

作者： Yu YAN Zhiyong LIU Xiaohong CHEN Liyan HUANG Center for Water resources and environment School of Civil EngineeringSun Yat-Sen UniversityGuangzhou510275China Southern Marine Science and engineering Guangdong Laboratory(Zhuhai) Zhuhai519082China

The hydrological system of a watershed is intricately influenced by both underlying characteristics and climate *** the variability in water yield is essential for effective water resources management and water security in the context of changing *** this study,we adopted the Budyko framework and leveraged simulations from the CMIP6 model to investigate the compensation effects of climate and underlying characteristics on watershed water *** on Taylor expansion and Budyko framework,we estimated the sensitivity of watershed water yield to climate and underlying characteristics(the first-and second-order partial derivatives).By combining external watershed characteristics(e.g.,water yield ratios and underlying characteristics)with internal sensitivity coefficients,this study further used vine copula and principal component analysis to quantify the stability of watershed water *** findings show:(1)Water-yield changes related to underlying characteristics could be offset by climate-related water-yield changes across all climate zones,maintaining the water yield ratio steady(i.e.,the compensation effects).(2)However,global watersheds will turn more sensitive to underlying characteristics and less sensitive to climate variation in the *** climate-and underlying-related sensitivities increase in watersheds with arid climates.(3)The stability of watershed water yield will gradually diminish in the *** 1901–1950to 2051–2100,the global stability of 280 watersheds drops from 0.054 to 0.021(i.e.,stability index identified by the joint probability).Particularly,the largest change in stability of water yield reaches-0.347±0.18 in arid *** semi-arid,semihumid,and humid regions,the changes are-0.039±0.010,-0.028±0.005,and-0.005±0.002,*** findings provide a reference for the future sustainable water resources development under climate change,highlighting the vulnerability of the water resources in ari

关键词： Hydrological system stability Compensation effects on water yield Sensitivities Budyko-Fu decomposition framework Global watersheds

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Design of dual-functional protic porous ionic liquids for boosting selective extractive desulfurization

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Petroleum Science 2024年第4期21卷 2817-2829页

作者： Jin-Rui Zhang Jie Yin Jing He Hong-Shun Ran Wei Jiang Hong-Ping Li Wen-Shuai Zhu Hua-Ming Li Ming Zhang school of the environment and Safety engineering & Institute for Energy Research Jiangsu University school of Chemistry and Chemical engineering Jiangsu University

Porous ionic liquids have demonstrated excellent performance in the field of separation, attributed to their high specific surface area and efficient mass transfer. Herein, task-specific protic porous ionic liquids(PPILs) were prepared by employing a novel one-step coupling neutralization reaction strategy for extractive desulfurization. The single-extraction efficiency of PPILs reached 75.0% for ***, adding aromatic hydrocarbon interferents resulted in a slight decrease in the extraction efficiency of PPILs(from 45.2% to 37.3%, 37.9%, and 33.5%), indicating the excellent extraction selectivity of PPILs. The experimental measurements and density functional theory calculations reveal that the surface channels of porous structures can selectively capture dibenzothiophene by the stronger electrophilicity(Eint(HS surface channel/DBT)=-39.8 kcal mol-1), and the multiple extraction sites of ion pairs can effectively enrich and transport dibenzothiophene from the oil phase into PPILs through π...π, C-H...π and hydrogen bonds interactions. Furthermore, this straightforward synthetic strategy can be employed in preparing porous liquids, offering new possibilities for synthesizing PPILs with tailored functionalities.

关键词： Protic porous ionic liquids Extractive desulfurization Selectivity Density functional theory

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