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Green Chemical engineering 2022年第4期3卷 395-404页

作者： Jianguo Liu Jiangmin Sun Thishana Singh Shanshan Lin Longlong Ma Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing210096China School of Energy Science and Engineering University of Science and Technology of ChinaHefei230026China University of Chinese Academy of Sciences Beijing100049China Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou510640China School of Chemistry and Physics University of KwaZulu-NatalDurban4000South Africa

Although precious transition metals such as palladium,platinum,and iridium are widely used in hydrogenation reactions,the earth-abundant transition metal-catalyzed highly selective semi-hydrogenation of terminal alkynes to terminal alkenes remains poorly developed and a *** we demonstrate the excellent selective,cost-effective semi-hydrogenation of terminal alkynes via a novel graphene encapsulated Ni@N/C *** graphene layer encapsulated nano-catalyst Ni@N/C could significantly avoid metal leaching and improve the stability of the *** strong interaction of nitrogen with the Ni nanoparticles regulates the activity of Ni towards selective semi-hydrogenation of terminal *** having un-functionalized as well as functionalized substituents,and substrates having sensitive functional groups(olefins,ketones)which pose a challenge to hydrogenate,were semi-hydrogenated with excellent conversion(up to 99%)and selectivity(up to 99%)under optimized reaction conditions.

关键词： Graphene Nitrogen doping Ni@N/C Semi-hydrogenation Terminal alkynes

Comparing the Thermal Conversion Behavior of Bio-Wastes in Various Molten Nitrates

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SSRN 2022年

作者： Yang, Yuhan Wang, Tiancheng Zou, Chan Xu, Kai Hu, Hongyun Gao, Linxia Li, Xian Yao, Hong State key Laboratory of Coal Combustion School of Energy and Power Engineering Huazhong University of Science and Technology Wuhan430074 China School of Civil & Environment engineering Hubei University of Technology Wuhan430068 China

In this paper, three kinds of molten nitrates were employed to conduct thermal conversion experiments of two bio-wastes. In addition, the effect of the inorganic matters in bio-waste on its thermal treatment process was also explored. The experimental results showed that NO 2 - has a higher reactivity compared with NO 3 - for the two bio-wastes. In detail, in contrast to NaNO 3 -KNO 3 salt, NaNO 3 -KNO 3 -NaNO 2 and NaNO 3 -NaNO 2 salts had a faster reaction rate and higher yield of gas products. From GC-MS analysis, it can be concluded that K + would inhibit the dehydroxylation process of phenols at 300 ℃, while the phenols were completely converted to the aromatic hydrocarbon with the increase of the temperature. In addition, nitrogenous heterocycle was produced due to the reaction between furans, aldehydes, ketones and NO 2 - /NO 3 - , and the nitrification process would be enhanced with the temperature. Furthermore, the inorganic components increased the weight loss temperature, while the thermal conversion of bio-wastes was promoted after reaching the reaction temperature. The research of this paper provides guidance for the selection of appropriate molten nitrate system and temperature for bio-waste treatment. © 2022, The Authors. All rights reserved.

关键词： Nitrates

Oxidation behavior and characterization of ZrO2/Cr94Al6 composite coated Zr-Sn alloy in 1000–1200 °C steam

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Ceramics International 2025年

作者： Zhou, Qian Chen, Hu Li, Xin Jin, Xiaoyue Du, Jiancheng Xu, Chi Liao, Bin Xue, Luwei Wang, Rongshan Zhao, Wanxiang Xue, Wenbin Key Laboratory of Beam Technology of Ministry of Education School of Physics and Astronomy Beijing Normal University Beijing100875 China Radiation Technology Institute Beijing Academy of Science and Technology Beijing100875 China Suzhou Nuclear Power Institute Suzhou215004 China National Engineering Research Center for Nuclear Power Plant Safety & Reliability Suzhou215004 China

A ZrO2/Cr94Al6 composite coating, denoted as the PEO/Cr94Al6, was successfully fabricated on Zr-Sn alloy using a combination of plasma electrolytic oxidation (PEO) and filtered cathodic vacuum arc deposition (FCVAD) technologies. The PEO process served to form an insulating ZrO2 ceramic interlayer, which not only acted as a physical barrier to impede the inter-diffusion between the Cr-based coating and the Zr substrate, but also inhibited the CrAl/Zr galvanic corrosion. The oxidation behavior of this ZrO2/Cr94Al6 -coated alloy in 1000–1200 °C steam was comprehensively evaluated. It was found that the mass gains of PEO/Cr94Al6-coated samples were merely 16.7 %, 22.5 % and 27.8 % of bare Zr-Sn alloy after 3600 s exposure in 1000 °C, 1100 °C and 1200 °C steam, respectively. The oxidative activation energy of bare and PEO/Cr94Al6-coated Zr-Sn alloys is 220.41 kJ/mol and 404.78 kJ/mol, respectively. Their excellent oxidation resistance was ascribed to the formation of outer Cr2O3 layer and the internal Al2O3 barrier layer above the residual CrAl layer. The thin Al2O3 barrier layer, in particular, effectively suppressed the inward diffusion of oxygen and played one key role in enhancing the oxidation resistance of composite coating. At 1000 °C and 1100 °C, a Cr2Zr inter-diffusion layer was formed between the CrAl layer and the Zr - Sn alloy substrate. However, at 1200 °C, a complex three-layer diffusion structure emerged, consisting of different Zr-Cr-O phases. This structure evolution was closely related to the diffusion of Cr, Al, and O elements, as well as the phase transformation of the PEO-derived ZrO2 layer to Zr3O and α-Zr(O). © 2025 Elsevier Ltd and Techna Group S.r.l.

关键词： Diffusion coatings

Organochlorine Pesticides in Water and Sediment at a Typical Karst Wetland in Southwest China

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SSRN 2024年

作者： Hu, Qianqian Liang, Yanpeng Zeng, Hong-Hu Huang, Huanfang Chen, Wenwen Qin, Litang Song, Xiaohong Yan, Xiaoyu College of Environmental Science and Engineering Guilin University of Technology Guilin541004 China Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology Guilin University of Technology Guilin541004 China State Environmental Protection Key Laboratory of Water Environmental Simulation and Pollution Control South China Institute of Environmental Sciences Ministry of Ecology and Environment Guangzhou510530 China Collaborative Innovation Center for Water Pollution Control and Water Security in Karst Region Guilin University of Technology Guilin541004 China

The Huixian karst wetland, situated in southwest China, is the largest karst wetland. Historically, organochlorine pesticides (OCPs) have negatively affected the aquatic environment and the health of surrounding residents. In this study, the pollution status and environmental fate of OCPs in multiple environmental media in the Huixian wetland were investigated. The 15 OCPs’ total concentration ranges in lake water, ditch water, groundwater, and lake sediment were 46.8–306 ng·L-1, 77.8–251 ng·L-1, 26.0–233 ng·L-1, and 44.8–345 ng·g-1, respectively. The concentrations and proportions of the different OCPs demonstrated significant seasonality. Historical residues are the main source of OCPs in the region, as evidenced by the typical ratios of DDTs to HCHs. Karst regions are extremely vulnerable to environmental change, as evidenced by the highly dynamic character of the karst wetland system and the rapid migration of multimodal OCPs in different media without considerable damage. According to the risk assessment, both the possible carcinogenic risk to sediments in the Huixian wetland and the ecological risk to water bodies were acceptable. In contrast, the consumption of lake water may put the local population at health risk, which is a cause of concern. © 2024, The Authors. All rights reserved.

关键词： Wetlands

An adaptive rainfall-runoff model for daily runoff prediction under the changing environment: Stream-LSTM

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environmental Modelling and Software 2025年 191卷

作者： Hu, Feichi Yang, Qinli Yang, Junran Shao, Junming Wang, Guoqing School of Resources and Environment University of Electronic Science and Technology of China No. 2006 Xiyuan Avenue Chengdu611731 China School of Computer Science and Engineering University of Electronic Science and Technology of China No. 2006 Xiyuan Avenue Chengdu611731 China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Nanjing210029 China

The rainfall-runoff relationship frequently undergoes changes and exhibits a non-stationary state due to the impacts of climate and human activities. This non-stationarity often results in performance degradation of most existing runoff prediction models, which were designed and applied under the assumption of a stationary rainfall-runoff relationship. This study proposes an adaptive rainfall-runoff model (Stream-LSTM (Stream-Long Short-Term Memory)) based on data stream mining and deep learning for 1-day-ahead daily runoff prediction. The model consists of two main components: (1) a dynamic threshold adjustment strategy that automatically detects changes in the rainfall-runoff relationship, and (2) a network fine-tuning approach that preserves long-term memory while adapting to new patterns. Results in the Source Region of the Yellow River basin demonstrate that the proposed model achieves Nash-Sutcliffe Efficiency (NSE) of 0.91 with a decay period of 10 in a changing environment, outperforming the widely used data-driven models such as Long Short-Term Memory (LSTM) (0.71), Random Forest (RF) (0.66), eXtreme Gradient Boosting (XGBoost) (0.69) and Support Vector Regression (SVR) (0.61). The Stream-LSTM model performed well on peak runoff prediction with NSE values generally exceeding 0.70. Additionally, preliminary inter-basin testing on two selected basins in the CAMELS dataset indicates the potential applicability of the method. This study provides a promising method for dynamic daily runoff prediction in a non-stationary environment, which is of great significance for flood mitigation and regional water resource management. © 2025 Elsevier Ltd

关键词： Resource allocation

Reaction of PMSE and PMWE to HF heating: comparison during a heater cycling 13

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Reaction of PMSE and PMWE to HF heating: comparison during a...

13th International Symposium on Antennas, Propagation and EM Theory, ISAPE 2021

作者： Ullah, Safi Li, Hailong Rauf, Abdur Wang, Maoyan Ge, ShuCan Meng, Lin School of Electronic Science and Engineering University of Electronic Science and Technology of China Chengdu610054 China Terahertz Science and Technology Key Laboratory of Sichuan Province Chengdu610054 China School of Physics University of Electronic Science and Technology of China Chengdu610054 China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave Propagation Qingdao266107 China

ISBN: (纸本)9781665418126

Using the EISCAT VHF radar observations, the comparison of reaction of polar mesosphere summer and winter echoes (PMSE and PMWE) to HF heating is presented. The response of PMSE and PMWE to HF heating shows a similar pattern however, it is found that HF heating effects on PMSE is 0.92 times greater than its effect on PMWE. In addition, after the heater switched-off, the overshoot produced in PMSE is 1.7 times greater than it produced in PMWE. Furthermore, due to HF heating, in PMSE the greater enhancement produced in electron temperature produces PMSE modulation 1.2 times greater than PMWE modulation. For greater statistical significance to the present conclusions further investigations with larger dataset are required. © 2021 IEEE.

关键词： Heating

Peroxymonosulfate Oxidation of Antibiotics Enhanced by Chloride Ion in Wastewater Under Different environmental Temperature and Ph

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SSRN 2024年

作者： Wei, Yulei Bao, Jie Lu, Zhiqi He, Xianglong Cui, Shuangshuang Li, Hongjing Song, Weihua Ma, Jun Department of Environmental Science & Engineering Fudan University Shanghai200433 China Suzhou New District Water Purification Co. Ltd Suzhou215000 China State Key Laboratory of Urban Water Resource and Environment Harbin Institute of Technology Harbin150090 China

The antibiotics and chloride ions (Cl−) coexist in the effluent of wastewater treatment plants (WWTPs). Peroxymonosulfate (PMS) oxidation of representative antibiotics enhanced by Cl− at relevant levels in wastewater under different environmental temperature and pH was studied. The second-order reaction rate constants of Cl− with PMS ranged from 0.52 × 10-3 to 2.33 × 10-3 M-1 s-1 (10 - 30 °C), and decreased from 1.97 × 10-3 to 0.65 × 10-3 M-1 s-1 when pH increased from 4 to 10. The kinetic model and experiments indicated that hypochlorous acid (HClO) and singlet oxygen (1O2) were major reactive species in the Cl−/PMS system. The degradation of sulfadiazine (SDZ) and oxytetracycline (OTC) were significantly accelerated by Cl−/PMS system, and HClO played a leading role in the presence of Cl−, whereas 1O2 dominated in the coexistence of Cl− and effluent organic matter. The concentrations of chlorinated by-products generated during SDZ and OTC oxidation by PMS were 0.99 - 16.97 μg/L. In secondary effluent obtained from a WWTP, the degradation rates of SDZ and OTC exhibited a positive correlation with increasing environmental temperature, and were relatively higher at pH 5.0 - 7.0. This work provides new insights into the effects of different environmental temperature and pH on PMS oxidation of antibiotics enhanced by Cl− in secondary effluent of WWTPs. © 2024, The Authors. All rights reserved.

关键词： Antibiotics

Recovering Spent Li-Ion Batteries As Li 2 Co 3 And Ncm Carbonate Precursor By Thermal Reduction And Co-Precipitation Combined Process

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SSRN 2024年

作者： Lu, Xingwen He, Yue Huang, Zebiao Li, Jiating Qi, Zenghua Wang, Fei School of Environmental Science and Engineering Guangdong University of Technology Guangzhou510006 China School of Environment Guangdong Key Laboratory of Environmental Pollution and Health Jinan University Guangzhou510632 China Guangzhou Urban Drainage Co. Ltd Guangdong Guangzhou510308 China

Addressing the escalating volume of retired lithium-ion batteries (LIBs) is crucial for protecting environment and minimizing resource wastage. In this study, Li2CO3 and NCM111 carbonate precursor (Ni0.33Co0.33Mn0.33CO3) were successfully generated from the retired ternary LIBs through a combined thermal reduction and carbonate precipitation process. During the thermal reduction process, graphite interacted with the cathode material (LiNi0.5Co0.2Mn0.3O2) from used LIBs, facilitating the conversion of Li from its LiOx polyhedral structure into Li2CO3. Simultaneously, the transition metals within LiNi0.5Co0.2Mn0.3O2 were transformed into Ni(0), Co(0), and MnO. Under optimal conditions, a graphite/LiNi0.5Co0.2Mn0.3O2 mass ratio of 0.15/1 was sintered at 750 °C for 2 h, resulting in the recovery of 98.7% Li as Li2CO3 with a purity of 99.8% through water leaching and evaporative crystallization. After isolating Li as Li2CO3 from waste NCMs, the residue was dissolved and co-precipitated as NCM111 carbonate precursor using ammonium complexing agents. The recovered precursors exhibited spherical morphology and rhodochrosite crystal structure. These results offer valuable insights on recycling valuable metals from used NCM batteries, thereby promoting the sustainability of the new energy industry. © 2024, The Authors. All rights reserved.

关键词： Lithium-ion batteries

Fractionation of Heavy Metals and Their Correlations with Magnetic Susceptibility in the Soil from a Typical Alluvial Island in the Lower Yangtze River, China

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SSRN 2023年

作者： Wang, Cheng Ma, Rong Wang, Jianhua Zhong, Cong Zhao, Yanping Browne, Patrick Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment Technology School of Environmental Science and Engineering Nanjing University of Information Science & Technology Nanjing210044 China Department of Terrestrial Magnetism Carnegie Institution of Washington WashingtonDC United States Key Laboratory of Environment Change and Resources Use in Beibu Gulf Ministry of Education Nanning Normal University Nanning530001 China Guangdong Institute of Analysis Guangzhou510070 China Institute of Earth Sciences and Engineering University of Auckland Auckland1142 New Zealand

Magnetic susceptibility (χ) was attempted to assess heavy metal pollution of soil by some researchers. As the previous investigations show both significant and no correlations between χ and heavy metals, whether χ can indicate effectively soil heavy metals pollution is of debate. The objectives of this investigation are to reveal the inter-relation between magnetic properties, iron oxides and heavy metals in the soil using a modified 5-step sequential extraction procedure (SEP) and to find an approach can assess effectively metal concentrations in soils using magnetic susceptibility measurements. The soil samples collected from a typical alluvial island in the lower Yangtze River, China, a total of 6 forms (exchangeable and acid soluble fraction, easily reducible fraction, oxidizable fraction, amorphous iron oxide, crystallized iron oxyhydroxides and residual fraction) were partitioned and their heavy metal concentrations and χ were ananlyzed. The results show that crystalline Fe oxyhydroxides and residual fractions are the two uppermost fractions of heavy metals. Combined the fractionations of elements with the change of χ of the soil during the processing of SEP, the exogenous source of Fe, Pb, Cd and Cr in the soil was speculated to be the vicinal steel production. Correlation analyses disclose a strong positive correlation between the concentrations of heavy metals and χ in the residual fraction, whereas the bulk soil shows no significant correlations between the concentrations of heavy metals and χ. It is suggested that it is more effective to assess the heavy metal pollution by the utilization of magnetic susceptibility measurements after removing the crystalline Fe oxyhydroxides in the soil. © 2023, The Authors. All rights reserved.

关键词： Heavy metals

xLSTM-UNet can be an Effective 2D & 3D Medical Image Segmentation Backbone with Vision-LSTM (ViL) better than its Mamba Counterpart

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arXiv

arXiv 2024年

作者： Chen, Tianrun Ding, Chaotao Zhu, Lanyun Xu, Tao Ji, Deyi Wang, Yan Zang, Ying Li, Zejian College of Computer Science and Technology Zhejiang University China Tech. Co. LTD China School of Information Engineering Huzhou University China Information Systems Technology and Design Pillar Singapore University of Technology and Design Singapore School of Software Technology Zhejiang University China School of Information Science and Technology University of Science and Technology of China China School of Instrumentation and Optoelectronic Engineering State Key Laboratory of Software Development Environment Beihang University China

Convolutional Neural Networks (CNNs) and Vision Transformers (ViT) have been pivotal in biomedical image segmentation. Yet, their ability to manage long-range dependencies remains constrained by inherent locality and computational overhead. To overcome these challenges, in this technical report, we first propose xLSTM-UNet, a UNet structured deep learning neural network that leverages Vision-LSTM (xLSTM) as its backbone for medical image segmentation. xLSTM has recently been proposed as the successor of Long Short-Term Memory (LSTM) networks and has demonstrated superior performance compared to Transformers and State Space Models (SSMs) like Mamba in Neural Language Processing (NLP) and image classification (as demonstrated in Vision-LSTM, or ViL implementation). Here, xLSTM-UNet we designed to extend the success in the biomedical image segmentation domain. By integrating the local feature extraction strengths of convolutional layers with the long-range dependency-capturing abilities of xLSTM, xLSTM-UNet offers a robust solution for comprehensive image analysis. We validate the efficacy of xLSTM-UNet through experiments. Our findings demonstrate that xLSTM-UNet consistently surpasses the performance of leading CNN-based, Transformer-based, and Mamba-based segmentation networks in multiple datasets in biomedical segmentation including organs in abdomen MRI, instruments in endoscopic images, and cells in microscopic images. With comprehensive experiments performed, this technical report highlights the potential of xLSTM-based architectures in advancing biomedical image analysis in both 2D and 3D. The code, models, and datasets are publicly available at http://***/xLSTM-Unet/. © 2024, CC BY-NC-ND.

关键词： Long short-term memory