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Atmospheric Hono Emissions in China: Unraveling the Spatiotemporal Patterns and Their key Influencing Factors

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SSRN 2023年

作者： Gan, Cong Li, Baojie Dong, Jinyan Li, Yan Zhao, Yongqi Wang, Teng Yang, Yang Liao, Hong Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control School of Environmental Science and Engineering Nanjing University of Information Science and Technology Nanjing210044 China College of Oceanography Hohai University Nanjing210013 China

Nitrous acid (HONO) can be photolyzed to produce hydroxyl radicals (OH). OH plays a crucial role in forming ozone (O3) and secondary organic aerosols (SOA) via various oxidation reactions. Despite the abundance of recent HONO studies, research on national HONO emissions in China remains relatively limited. Therefore, this study employed the "wetting-drying" model and developed a high-resolution gridded inventory of HONO emissions for mainland China using multiple data such as land-cover types, fertilization, temperature, precipitation, and soil physical and chemical properties. We used the Monte Carlo method to estimate the uncertainty in HONO emissions. In addition, the primary sources of HONO emissions were identified and their spatiotemporal distribution and main influencing factors were studied. The results indicated that the total HONO emissions in mainland China in 2016 were 0.68 Tg N (0.47–0.91 Tg N), with cropland (0.29 Tg N) and fertilization (0.25 Tg N) as the primary sources, jointly contributing to over 78% of the ***, the North China Plain (NCP) had the highest HONO emission density (3.11 kg N/ha/yr). Seasonal HONO emissions followed the order: summer (0.36 g N/ha) > spring (0.16 g N/ha) > autumn (0.15 g N/ha) > winter (0.04 g N/ha). Moreover, HONO emissions displayed positive correlations with fertilization (r = 0.85), cropland (r = 0.72), temperature (r = 0.84), and precipitation (r = 0.63), and a negative correlation with wind speed (r = -0.24). This study provides vital scientific groundwork for the atmospheric nitrogen cycle and the formation of secondary pollutants. © 2023, The Authors. All rights reserved.

关键词： Monte Carlo methods

An Efficient Fe2+ Assisted Uv/Electrogenerated-Chlorine Process for Carbamazepine Degradation: The Role of Fe(Iv)

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SSRN 2022年

作者： Yin, Haoran Zhang, Qizhan Jing, Jiana Wang, Xuechun Yin, Xiaoya Zhou, Minghua Key Laboratory of Pollution Process and Environmental Criteria Ministry of Education College of Environmental Science and Engineering Nankai University Tianjin300350 China Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution College of Environmental Science and Engineering Nankai University Tianjin300350 China Tianjin Advanced Water Treatment Technology International Joint Research Center College of Environmental Science and Engineering Nankai University Tianjin300350 China Tianjin Fisheries Research Institute Tianjin300221 China

To improve the performance and solve the restrictions of UV/chlorine process (e.g., the narrow pH application range and high disinfection by-products (DBPs) formation), a Fe2+ assisted advanced oxidation process with electrochemically generated chlorine (UV/E-Cl/Fe2+) was proposed for carbamazepine (CBZ) degradation, which eliminated CBZ (5 mg/L) within 4 min under the optimal conditions. Compared with UV/electro-generated chlorine (UV/E-Cl) and anodic oxidation-chlorination/Fe2+ (AO-Cl/Fe2+) processes, the apparent first-order kinetics constant in UV/E-Cl/Fe2+ increased by 2.56 and 3.18 times respectively, and the energy consumption was lower (1.15 kWh/m3-log). Simultaneously, the pH application range could be expanded to 9, and DBPs formed in this process were 17.1% less than those in UV/E-Cl. Through quenching tests, electron paramagnetic resonance (EPR) experiments, measurement of •OH concentration, quantification of methyl phenyl sulfoxide (PMSO) and benzosulfone (PMSO2) and processes comparison, possible CBZ degradation pathways and mechanism of UV/E-Cl/Fe2+ were proposed, in which Fe(IV) played the dominant role in the early stage, while the production of radicals (i.e., •OH and Cl•) was enhanced with the increase of chlorine generation, accelerating the CBZ removal. Furthermore, this process demonstrated wide application prospect in treating various contaminants and real wastewaters. In conclusion, this study offers an effective and energy-efficient method for organic pollutants degradation. © 2022, The Authors. All rights reserved.

关键词： Iron compounds

Naturally Aged Polylactic Acid Microplastics Stunted Pakchoi (Brassica Rapa Subsp. Chinensis) Growth with Cadmium in Soil

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SSRN 2023年

作者： Zuo, Jiane Xie, Zhenwen Men, Cong Yuan, Xin Miao, Sun Sun, Quanyi Hu, Jiamin Zhang, Yanyan Liu, Yuxin State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Tsinghua University Beijing100084 China Shenzhen International Graduate School Tsinghua University Shenzhen518055 China School of Energy and Environmental Engineering Beijing Key Laboratory of Resource-Oriented Treatment of Industrial pollutants University of Science and Technology Beijing Beijing100083 China

Biodegradable microplastics (BMPs) and cadmium (Cd) are posing threats to agro-systems especially to plants and current studies mostly used virgin BMPs to explore their ecological effects. However, effects of naturally aged BMPs and their combined effects with Cd on pakchoi are yet to be unraveled. Therefore, this study incubated naturally aged polylactic acid (PLA) MPs through soil aging process, and investigated the single and combined effects of Cd and PLA MPs (virgin and aged) on pakchoi (Brassica rapa subsp. Chinensis) morphology, anti-oxidant systems and soil microbial activities. Our results found that after being deposited in soil for six months, aged PLA (PLAa) MPs formed with a fractured surface, demonstrating more detrimental effects on pakchoi than virgin ones. PLA/PLAa MPs and Cd stunted pakchoi growth, caused oxidative stress and altered the biophysical environment in soil, separately. Moreover, co-existence of PLA/PLAa MPs and Cd caused greater damages to pakchoi than applied alone. The co-presence of PLAa MPs and Cd inhibited pakchoi biomass accumulation rate by 92.2% compared with the no-addition group. The results unraveled here emphasized BMPs, especially aged BMPs, could trigger negative effects on agro-systems with heavy metals. These findings will give reference to future holistic assessment of BMPs ecological effects. © 2023, The Authors. All rights reserved.

关键词： Cadmium

Enhanced Electron Transfer-Based Nonradical Activation of Peroxymonosulfate by Conx Sites Anchored on Carbon Nitride Nanotubes for the Removal of Organic Pollutants

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SSRN 2023年

作者： Sun, Yongjun Xu, Baokang Zhang, Xiao Zhang, Yue Wang, Shiwen Yu, Peng Li, Xi Xu, Yanhua School of Environmental Science and Engineering Nanjing Tech University Nanjing211816 China Jiangsu Key Laboratory of Industrial Pollution Control and Resource Reuse School of Environmental Engineering Xuzhou University of Technology Xuzhou221018 China College of Urban Construction Nanjing Tech University Nanjing211816 China

The nonradical pathway selectively oxidizes pollutants with less interference from environmental factors, which can effectively improve the environmental suitability of peroxymonosulfate (PMS) activation. Herein, a Co-doped nanotubular carbon nitride catalyst (Co-CNNT) based on CoNx sites was constructed for stable and efficient PMS activation with a better specific surface area, number of CoNx sites, and electron transfer capability than Co-doped lamellar carbon nitride catalyst (Co-CN). Co-CNNT improved PMS utilization efficiency (~50%) and enhanced the contribution of the electron transfer pathway to tetracycline (TET) degradation. The superior charge transfer properties of Co-CNNT and the enhanced PMS adsorption capacity of the CoNx site are endogenous factors to achieve electron transfer pathway-dominated PMS activation. Therefore, the Co-CNNT/PMS system could effectively destroy electron-rich or low-potential pollutants within 24 min. The stronger environmental adaptability allows it to maintain catalytic activity in complex aqueous matrices, achieving effective oxidation of diluted tetracycline-based pharmaceutical wastewater. The practical significance of this study is the induction of the nonradical PMS activation pathway by changing the catalyst morphology, which provides theoretical guidance for the practical environmental application of nonradical PMS activation. © 2023, The Authors. All rights reserved.

关键词： Carbon nitride

Novel Pei@Csh Adsorbents Derived from Coal Fly Ash Enabling Efficient and In-Situ CO2 Capture: The Anti-Urea Mechanism of Pore-Expanded Csh Support

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SSRN 2022年

作者： Qu, Fan Yan, Feng Shen, Xuehua Li, Chunyan Chen, Heijin Zhang, Zuotai School of Environmental Science and Engineering Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control Southern University of Science and Technology Shenzhen518055 China Key Laboratory of Municipal Solid Waste Recycling Technology and Management of Shenzhen City Shenzhen518055 China

The solid amine adsorption is considered to be the most promising technology for post-combustion CO2 capture, but it still has drawbacks for high cost of support materials and easy occurrence of CO2-induced chemical deactivation. Herein, we proposed a novel environmentally friendly method for efficient and stable solid amine adsorbents: The calcium silicate hydrate (CSH) support with pore volume of 3.0 cm3·g-1 was synthesized from coal fly ash (CFA) with the pore-expanded assistance of azeotropic distillation, and then the PEI@CSH adsorbents were prepared by impregnating polyethylenimine (PEI) into the pores of CSH support. The adsorption capacity of the prepared 60%PEI@CSH-0.1 adsorbent reached 198 mg·g-1 and exhibited excellent cyclic stability of only 1.9% attenuation after 10 cycles under ideal regeneration conditions. Even under realistic regeneration conditions (at 150 ℃ with 100% CO2), the CO2 uptake still remained 103 mg·g-1 after 10 cycles, which showed obvious advantages than the commercial SiO2 supports. A serials of characterization techniques of FT-IR, solid-state NMR and DFT calculation were performed to explained the anti-urea mechanism of CSH support;consequently, the CSH support promoted the conversion of primary amines to secondary amines in PEI molecules, and thus effectively inhibited the inactivation caused by the formation of urea compounds. Therefore, the PEI@CSH adsorbents provides a low-cost and high-efficiency approach for both in-situ CFA utilization and CO2 mitigation inside the coal-fired power plants. © 2022, The Authors. All rights reserved.

关键词： Urea

PM2.5-O3 Compound Pollution Pattern Recognition Based on Hybrid Model of tensor Decomposition and Spectral Clustering

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PM2.5-O3 Compound Pollution Pattern Recognition Based on Hyb...

Digital Society and Intelligent Systems (DSInS), International Conference on

作者： Wanhua Li Dongmei Hu Yafei Guo Jiaqi Dong MOE Key Laboratory of Resources and Environmental System Optimization College of Environmental Science and Engineering The North China Electric Power University Beijing China Engineering Research Center of Clean and Low-Carbon Technology for Intelligent Transportation Ministry of Education School of Environment Beijing Jiaotong University Beijing China

Clustering intra-urban areas with the same pollution characteristics can help to accurately manage intra-urban air pollution. In this study, a new classification model for PM 2.5 -O 3 composite pollution features is established based on tensor decomposition and spectral clustering methods. The tensor decomposition was utilized to extract pollution features from massive air pollutant concentration data, and the pollution concentration data were decomposed into day-by-day, intra-day, and spatial modes, which provided a low-dimensional space for the subsequent spectral clustering and fine clustering classification process of the urban spatial-scale PM 2.5 -O 3 composite pollution conditions. The model is explored by taking the annual PM 2.5 and O 3 pollution conditions in Beijing in 2017 and 2020 as an example, discussing the differences in geographic locations and pollution characteristics between the different models, and explaining the changes in the city’s pollution characteristics from 2017 to 2020. Through this new hybrid method, scientific support can be provided for urban refinement and precise management.

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Beam Pattern Modulation Embedded Hybrid Transceiver Optimization for Integrated Sensing and Communication

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arXiv

arXiv 2024年

作者： Liu, Boxun Gao, Shijian Yang, Zonghui Cheng, Xiang Yang, Liuqing State Key Laboratory of Advanced Optical Communication Systems and Networks School of Electronics Peking University Beijing100871 China Guangzhou511400 China Guangzhou511400 China Department of Electronic and Computer Engineering the Department of Civil and Environmental Engineering The Hong Kong University of Science and Technology Hong Kong

Integrated sensing and communication (ISAC) emerges as a promising technology for 6G, particularly in the millimeter-wave (mmWave) band. However, the widely utilized hybrid architecture in mmWave systems compromises multiplexing gain due to the constraints of limited radio-frequency (RF) chains. Moreover, additional sensing functionalities exacerbate the impairment of spectrum efficiency (SE). In this paper, we present an optimized beam pattern modulation-embedded ISAC (BPM-ISAC) transceiver design, which spares one RF chain for sensing and uses the remaining ones for communication. To compensate for the reduced SE, index modulation across communication beams is applied. We formulate an optimization problem aimed at minimizing the mean squared error (MSE) of the sensing beampattern, subject to a symbol MSE constraint. This problem is then solved by sequentially optimizing the analog and digital parts. Both the multi-aperture structure (MAS) and the multi-beam structure (MBS) are considered in the analog part. We conduct theoretical analysis on the asymptotic pairwise error probability (APEP) and the Cramér-Rao bound (CRB) of direction of arrival (DoA) estimation. Numerical simulations validate the overall enhanced ISAC performance over existing alternatives. Copyright © 2024, The Authors. All rights reserved.

关键词： Mean square error

Viscosity Determination of the Biomass Slag in the SiO2-CaO-K2O System Based on the Bond Distribution

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SSRN 2023年

作者： He, Chong Fan, Feifei Guo, Jing Yuan, Mengran Qin, Yuhong Wei, Yuexing Yan, Jingchong College of Environmental Science and Engineering Taiyuan University of Technology Taiyuan030024 China College of Safety and Emergency Management Engineering Taiyuan University of Technology Taiyuan030024 China Shanxi Key Laboratory of Compound Air Pollutions Identification and Control Taiyuan University of Technology Taiyuan030024 China School of Chemistry & Chemical Engineering Anhui Province Key Laboratory of Coal Clean Conversion and High Valued Utilization Anhui University of Technology 243032 China

The slag mobility is a key factor influencing the slag tapping process during the slagging gasification of biomass. However, the viscosity model suitable for the biomass slag (relevant to the SiO2-CaO-K2O system) has not been reported yet. This study firstly proposed an Arrhenius-type viscosity model based on the bond distribution in biomass slag. The bond information of the biomass slag was determined by thermodynamic modelling. The quantified relation between the slag composition (SiO2, K2O, and CaO) and bond distribution (Si-Si-O-O, Si-K-O-O, and Si-Ca-O-O), and the relation between the bond distribution and activation energy of viscous flow (Ea) or pre-exponential factor (A) were established, respectively. The newly built viscosity model shows excellent prediction performance in the viscosity range of 0-100 Pa⋅s with the R2 of 0.91 and a standard error of 1.71 Pa⋅s. © 2023, The Authors. All rights reserved.

关键词： Slags

A Hierarchical Core-Sheath Structure Composite Fiber of Pw/Tpu for Elastic Smart Fabrics Enabling Wearable Personal Thermal Management

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SSRN 2023年

作者： Hu, Luyang Chen, Jiadong She, Jing Li, Fabing Liao, Junjie Zhou, Yufeng Zhang, Yumin School of Materials Science and Engineering Anhui University of Science and Technology Huainan232001 China Anhui International Joint Research Center for Nano Carbon-based Materials and Environmental Health Huainan232001 China National Key Laboratory of Science and Technology on Advanced Composites in Special Environment Harbin150001 China

Elasticity and stability play a crucial role in phase change fibers (PCFs), ensuring both comfort and effective thermal management in fabrics. In this study, we present the development of an elastic and shape-stable phase change fiber through coaxial wet spinning. The fiber consists of a paraffin wax (PW) core encapsulated in a thermoplastic polyurethane (TPU) sheath, providing reliable protection against leakage during use. The obtained PCFs exhibit a PW loading capacity of up to 64.9 wt.% and a heating enthalpy of 117.0 J/g. Notably, these fibers maintain their morphological and thermal stability even after undergoing 50 cycles of heating and cooling treatments. By integrating the PCFs into a fabric and coating the surface with CNTs, the PCFs-based fabric achieves an outstanding photothermal conversion efficiency of 95.1% under a light intensity of 250 mW/cm2 and an electrothermal conversion efficiency of 73.2% at a power level of 0.9 W. Furthermore, the fabric, woven with uniformly broken PW core, exhibits excellent tensile resilience in various conditions, including room temperature and during photothermal and electrothermal conversion processes. This study introduces a promising avenue for the development of innovative PCFs, offering significant potential for their application in the realm of personal smart fabrics, particularly in the field of advanced thermal management. © 2023, The Authors. All rights reserved.

关键词： Fibers