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The main strategies for soil pollution apportionment:A review of the numerical methods

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Journal of Environmental Sciences 2024年第2期136卷 95-109页

作者： bin Shi Jing meng TieyuWang Qianqian Li Qifan Zhang Guijin Su Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Guangdong Provincial Key Laboratory of Marine Disaster Prediction and Prevention Shantou UniversityShantou 515063China

Nowadays,a large number of compounds with different physical and chemical properties have been determined in soil.Environmental behaviors and source identification of pollutants in soil are the foundation of soil pollution control.Identification and quantitative analysis of potential pollution sources are the prerequisites for its prevention and control.Many efforts have made to develop methods for identifying the sources of soil pollutants.These efforts have involved the measurement of source and receptor parameters and the analysis of their relationships via numerical statistics methods.We have comprehensively reviewed the progress made in the development of source apportionment methodologies to date and present our synthesis.The numerical methods,such as spatial geostatistics analysis,receptor models,and machine learning methods are addressed in depth.In most cases,however,the effectiveness of any single approach for source apportionment remains limited.Combining multiple methods to address soil quality problems can reduce uncertainty about the sources of soil pollution.This review also constructively highlights the key strategies of combining mathematical models with the assessment of chemical profiles to provide more accurate source attribution.This review intends to provide a comprehensive summary of source apportionment methodologies to help promote further development.

关键词： Soil pollutants Source attribution Methodologies Chemical profiles Mathematical models

Endogenous Candida albicans endophthalmitis in a patient with chronic renal failure on hemodialysis

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International Journal of Ophthalmology(English edition) 2024年第5期17卷 979-981页

作者： meng-ya Liu Zhi-Fan Chen Hao-Sheng Liu Qian-Li meng Department of Ophthalmology Guangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhou 510080Guangdong ProvinceChina The Fourth Affiliated Hospital of Guangzhou Medical University Guangzhou 511400Guangdong ProvinceChina

Dear Editor,We report a rare case of endogenous endophthalmitis caused by Candida albicans in a patient with chronic renal failure concomitant hemodialysis.A 71-year-old man with a history of hypertension and 2-year chronic renal failure on hemodialysis via a native arteriovenous fistula(AVF)was presented to the local hospital due to fever 3wk ago.No pathogens were detected through blood culture on admission,and his fever gradually subsided with intravenous ceftriaxone sodium.After a week of fever,he experienced progressive blurred vision in both eyes,accompanied by pain and headaches.Subsequent magnetic resonance imaging(MRI)of the brain revealed sinusitis.He had not undergone any previous eye surgeries or trauma.

关键词： hemodialysis albicans fever

Numerical study on the effective thermal conductivity and thermal tortuosity of porous media with different morphologies

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Science China Technological Sciences 2024年第6期67卷 1685-1694页

作者： DU Shen LI Dong LI meng-Jie HE ya-Ling Key Laboratory of Thermo-Fluid Science and Engineering of Ministry of Education School of Energy and Power Engineering Xi’an Jiaotong University

Effective thermal conductivity and thermal tortuosity are crucial parameters for evaluating the effectiveness of heat conduction within porous media. The direct pore-scale numerical simulation method is applied to investigate the heat conduction processes inside porous structures with different morphologies. The thermal conduction performances of idealized porous structures are directly compared with real foams across a wide range of porosity. Real foam structures are reconstructed using X-ray computed tomography and image processing techniques, while Kelvin and Weaire-Phelan structures are generated through periodic unit cell reconstruction. The detailed temperature fields inside the porous structures are determined by solving the heat conduction equation at the pore scale. The results present that the equivalent thermal conductivity of Kelvin and Weaire-Phelan structures is similar to and greater than that of the real foam structure with the same strut porosity. The thermal tortuosity of real foam structure is relatively larger and the heat conduction path becomes straighter by adopting the anisotropic design. The thermal tortuosity of the fluid channels for Kelvin, Weaire-Phelan, and real foam structures is close to one. The thermal conductivity of porous structures with heat transfer fluid increases as the thermal conductivity ratio of fluid to solid becomes larger. A small porosity of porous media leads to a larger equivalent thermal conductivity due to the dominant contribution of porous skeleton in the heat conduction process. Correlations derived from parallel and series models, as well as the Maxwell-Eucken models,provide decent predictions of effective thermal conductivity, with an average error of less than 8% in the entire range of thermal conductivity ratio.

关键词： volumetric solar receiver porous morphology direct pore-scale simulation equivalent thermal conductivity thermal tortuosity empirical correlation

Churning loss characteristics of a wet three-phase high-speed reluctance motor

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第3期25卷 251-267页

作者： Zhenzhou ZHANG Mingzhu DAI Chenchen ZHANG Yi CHEN bin meng College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310023China

With the increasing requirements of electro-hydrostatic actuators(EHAs)for power,volume,and pressure,there is a growing tendency in the industry to combine the motor and pump to form a so-called'motor pump'to improve the integration.In this paper,a novel structure for a wet three-phase high-speed reluctance motor pump is proposed,which can further improve integration by removing the dynamic seal on the pump shaft,thereby avoiding the problems of dynamic seal wear and oil leakage and improving heat dissipation under high-speed working conditions.However,after the motor is wetted,the churning loss caused by immersion of the rotor in the oil causes additional fluid resistance torque.Based on fundamental fluid mechanics,an analytical model of the churning torque of a wet motor was established.To verify the accuracy of the analytical model,a simulation model of churning loss was established based on computational fluid dynamics(CFD),and the churning torque and flow field state were analyzed.Finally,an experimental prototype was designed and manufactured,and a test bench for churning loss was built.The oil churning torque was measured at different speeds and temperatures.The results from the analytical,simulation,and experimental models agreed well.The experimental results validated the analytical model and CFD simulation.This research provides a practical method for calculating the churning loss and serves as guidance for future optimization of churning loss reduction.

关键词： Motor pump Wet motor Churning loss Analytical model Computational fluid dynamics(CFD)

Catalytic degradation of chlorinated volatile organic compounds(CVOCs)over Ce-Mn-Ti composite oxide catalysts

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Journal of Environmental Sciences 2024年第4期138卷 326-338页

作者： Zhiwei Zhou Qianqian Li Guijin Su Jiaxin Pang Bohua Sun Jing meng bin Shi Henan Institute of Advanced Technology Zhengzhou UniversityZhengzhou 450052China Key Laboratory of Environmental Nanotechnology and Health Effects State Key Laboratory of Environmental Chemistry and EcotoxicologyResearch Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

Developing industrially moldable catalysts with harmonized redox performance and acidity is of great significance for the efficient disposal of chlorinated volatile organic compounds(CVOCs)in actual exhaust gasses.Here,commercial TiO_(2),typically used for molding catalysts,was chosen as the carrier to fabricate a series of Ce_(0.02)Mn_(0-0.24)TiO_(x) materials with different Mn doping ratios and employed for chlorobenzene(CB)destruction.The introduction of Mn remarkedly facilitated the synergistic effect of each element via the electron transfer processes:Ce^(3+)+Mn^(4+/3+)■Ce^(4+)+Mn^(3+/2+)and Mn^(4+/3+)+Ti^(4+)■Mn^(3+/2+)+Ti^(3+).These synergistic interactions in Ce_(0.02)Mn_(0.04-0.24)TiO_(x),especially Ce_(0.02)Mn_(0.16)TiO_(x),significantly elevated the active oxygen species,oxygen vacancies and redox properties,endowing the superior catalytic oxidation of CB.When the Mn doping amount increased to 0.24,a separate Mn_(3)O_(4) phase appeared,which in turn might weaken the synergistic effect.Furthermore,the acidity of Ce_(0.02)Mn_(0.04-0.24)TiO_(x) was decreased with the Mn doping,regulating the balance of redox property and acidity.Notably,Ce_(0.02)Mn_(0.16)TiO_(x) featured relatively abundant B-acid sites.Its coordinating redox ability and moderate acidity promoted the deep oxidation of CB and RCOOH-intermediates,as well as the rapid desorption of Cl species,thus obtaining sustainable reactivity.In comparison,CeTiO_(x) owned the strongest acidity,however,its poor redox property was not sufficient for the timely oxidative decomposition of the easier adsorbed CB,resulting in its rapid deactivation.This finding provides a promising strategy for the construction of efficient commercial molding catalysts to decompose the industrial-scale CVOCs.

关键词： Chlorobenzene Ce_(0.02)Mn_(0-0.2)4tiox materials Redox ability Acidity Synergistic interaction

Source apportionment and suitability evaluation of seasonal VOCs contaminants in the soil around a typical refining-chemical integration park in China

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Journal of Environmental Sciences 2024年第3期137卷 651-663页

作者： Xu Zhao Jing meng Qianqian Li Guijin Su Qifan Zhang bin Shi Lingwen Dai Yong Yu Key Laboratory of Environmental Nanotechnology and Health Effects State Key Laboratory of Environmental Chemistry and EcotoxicologyResearch Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China State Environmental Protection Key Laboratory of Quality Control in Environmental Monitoring China National Environmental Monitoring CenterBeijing 100012China

Accurate source apportionment of volatile organic compounds(VOCs)in soil nearby petrochemical industries prevailing globally,is critical for preventing pollution.However,in the process,seasonal effect on contamination pathways and accumulation of soil VOCs is often neglected.Herein,yanshan Refining-Chemical Integration Park,including a carpet,refining,synthetic rubber,and two synthetic resin zones,was selected for traceability.Season variations resulted in a gradual decrease of 31 VOCs in soil from winter to summer.A method of dry deposition resistance model coupling partitioning coefficient model was created,revealing that dry deposition by gas phase was the primary pathway for VOCs to enter soil in winter and spring,with 100 times higher fux than by particle phase.Source profiles for five zones were built by gas sampling with distinct substance indicators screened,which were used for positive matrix factorization factors determination.Contributions of the five zones were 14.9%,20.8%,13.6%,22.1%,and 28.6%in winter and 33.4%,12.5%,10.7%,24.9%,and 18.5%in spring,respectively.The variation in the soil sorption capacity of VOCs causes inter-seasonal differences in contribution.The better correlation between dry deposition capacity and soil storage of VOCs made root mean square and mean absolute errors decrease averagely by 8.8%and 5.5%in winter compared to spring.This study provides new perspectives and methods for the source apportionment of soil VOCs contamination in industrial sites.

关键词： Dry deposition resistance model Positive matrix factorization model Partitioning coefficient model Contamination pathway Source profile

Effect of Nozzle Inclination Angle on Fuel-Air Mixing and Combustion in a Heavy Fuel Engine

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Fluid Dynamics & Materials Processing 2024年第2期20卷 365-382页

作者： Zhigang Wang bin Zheng Peidong Zhao Baoli Wang Fanyan meng Wenke Xu Jian meng School of Transportation and Vehicle Engineering Shandong University of TechnologyZibo255049China

Heavy-fuel engines are widely used in UAVs(Unmanned Autonomous Vehicles)because of their reliability and high-power density.In this study,a combustion model for an in-cylinder direct injection engine has been imple-mented using the AVL FIRE software.The effects of the angle of nozzle inclination on fuel evaporation,mixture distribution,and combustion in the engine cylinder have been systematically studied at 5500 r/min and consider-ing full load cruise conditions.According to the results,as the angle of nozzle inclination increases,the maximum combustion explosion pressure in the cylinderﬁrst increases and then it decreases.When the angle of nozzle incli-nation is less than 45°,the quality of the mixture in the cylinder and the combustion performance can be improved by increasing the angle.When the angle of nozzle inclination is greater than 45°,however,the mixture unevenness increases slightly with the angle,leading to a deterioration of the combustion performances.When the angle of nozzle inclination is between 35°and 55°,the overall combustion performance of the engine is rela-tively good.When the angle of nozzle inclination is 45°,the combustion chamber’s geometry and the cylinder’s airﬂow are well matched with the fuel spray,and the mixture quality is the best.Compared with 25°,the peak heat release rate increases by 20%,and the maximum combustion burst pressure increases by 5.5%.

关键词： Aviation heavy fuel piston engine nozzle inclination angle combustion fuel-air mixing

Secoemestrin C Ameliorates Psoriasis-like Skin Inflammation in Mice by Suppressing the TNF-α/NF-κB Signaling Pathway

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Current Medical Science 2024年第1期44卷 232-240页

作者： Zhi-bin ZHU meng-jie LIU Jing WANG Zhou SHU Jie CAO Department of Stomatology Chengdu Seventh People's HospitalChengdu 610044China Department of Pharmacy Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430022China

Objective Secoemestrin C(SC),an epitetrathiodioxopiperazine isolated from Aspergillus nidulans,has been previously reported to have immunomodulatory and hepatoprotective effects against acute autoimmune hepatitis.However,the effect of SC on regulating the inflammation and its underlying mechanisms in the pathogenesis of psoriasis remain unclear.This study aimed to evaluate the effects of SC on inflammatory dermatosis both in vitro and in vivo.Methods In vitro,HaCaT cells were induced with tumor necrosis factor-alpha(TNF-α,10 ng/mL)to establish an inflammatory injury model,and the expression of nuclear transcription factor-κB(NF-κB)pathway components was measured using qRT-PCR and Western blotting.An in vivo mouse model of imiquimod(IMQ)-induced psoriasis-like skin inflammation was used to evaluate the effectiveness of SC in alleviating psoriasis.Results SC significantly blocked the activation of NF-κB signaling in TNF-α-stimulated HaCaT cells.In addition,systemic and local administration of SC improved psoriatic dermatitis in the IMQ-induced mouse model.SC reduced skin scale and significantly inhibited the secretion of inflammatory factors in skin lesions.Conclusion The protective effect of SC against psoriatic-associated inflammation reveals its potential therapeutic value for treating psoriasis.

关键词： secoemestrin C(SC) psoriasis tumor necrosis factor-alpha(TNF-α) nuclear transcription factor-kB(NF-kB) inflammation

Diphylleia Grayi-Inspired Intelligent Temperature-Responsive Transparent Nanofiber Membranes

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Nano-Micro Letters 2024年第4期16卷 67-78页

作者： Cengceng Zhao Gaohui Liu yanyan Lin Xueqin Li Na meng Xianfeng Wang Shaoju Fu Jianyong Yu bin Ding Shanghai Frontier Science Research Center of Advanced Textiles College of TextilesDonghua UniversityShanghai 201620People’s Republic of China

Nanofiber membranes(NFMs) have become attractive candidates for next-generation flexible transparent materials due to their exceptional flexibility and breathability. However, improving the transmittance of NFMs is a great challenge due to the enormous reflection and incredibly poor transmission generated by the nanofiber-air interface. In this research, we report a general strategy for the preparation of flexible temperature-responsive transparent(TRT) membranes,which achieves a rapid transformation of NFMs from opaque to highly transparent under a narrow temperature window. In this process, the phase change material eicosane is coated on the surface of the polyurethane nanofibers by electrospray technology. When the temperature rises to 37 ℃, eicosane rapidly completes the phase transition and establishes the light transmission path between the nanofibers, preventing light loss from reflection at the nanofiber-air interface. The resulting TRT membrane exhibits high transmittance(> 90%), and fast response(5 s). This study achieves the first TRT transition of NFMs, offering a general strategy for building highly transparent nanofiber materials, shaping the future of next-generation intelligent temperature monitoring, anti-counterfeiting measures, and other high-performance devices.

关键词： Biomimetic Transparent Nanofibrous membrane Temperature response Phase change materials