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Novel algorithm for detection and identification of radioactive materials in an urban environment

Nuclear Science and Techniques 2023年第10期34卷 103-116页

作者： Hao-Lin Liu Hai-Bo Ji Jiang-Mei Zhang Jing Lu Cao-Lin Zhang Xing-Hua Feng Department of Automation University of Science and Technology of ChinaHefei 230026China School of Information Engineering Southwest University of Science and TechnologyMianyang 621010China Fundamental Science on Nuclear wastes and environment Safety Laboratory Southwest University of Science and TechnologyMianyang 621010China School of Automation and Information Engineering Sichuan University of Science and EngineeringZigong 643000China

This study introduces a novel algorithm to detect and identify radioactive materials in urban settings using time-series detector response data. To address the challenges posed by varying backgrounds and to enhance the quality and reliability of the energy spectrum data, we devised a temporal energy window. This partitioned the time-series detector response data, resulting in energy spectra that emphasize the vital information pertaining to radioactive materials. We then extracted characteristic features of these energy spectra, relying on the formation mechanism and measurement principles of the gammaray instrument spectrum. These features encompassed aggregated counts, peak-to-flat ratios, and peak-to-peak ratios. This methodology not only simplified the interpretation of the energy spectra's physical significance but also eliminated the necessity for peak searching and individual peak analyses. Given the requirements of imbalanced multi-classification, we created a detection and identification model using a weighted k-nearest neighbors(KNN) framework. This model recognized that energy spectra of identical radioactive materials exhibit minimal inter-class similarity. Consequently, it considerably boosted the classification accuracy of minority classes, enhancing the classifier's overall efficacy. We also executed a series of comparative experiments. Established methods for radionuclide identification classification, such as standard KNN, support vector machine, Bayesian network, and random tree, were used for comparison purposes. Our proposed algorithm realized an F1 measure of 0.9868 on the time-series detector response data, reflecting a minimum enhancement of 0.3% in comparison with other techniques. The results conclusively show that our algorithm outperforms others when applied to time-series detector response data in urban contexts.

关键词： Gamma-ray spectral analysis Nuclide identification Urban environment Temporal energy window Peakratio spectrum analysis Weighted KNN

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具有层级互联孔道的拒盐碳气凝胶太阳能蒸发器用于高盐废水处理

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Science China Materials 2023年第8期66卷 3300-3309页

作者：钟鹭斌陈殊珏侯旭张琪骏郭朝阳郑煜铭 CAS Key Laboratory of Urban Pollutant Conversion Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China College of Resources and environment Fujian Agriculture and Forestry UniversityFuzhou 350002China State Key Laboratory of physical Chemistry of solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China

太阳能蒸发是一种可持续的高盐废水处理技术,然而运行中蒸发器表面的盐积累会严重缩短蒸发器的寿命.如何使蒸发器兼具高蒸发效率和良好拒盐性是目前面临的挑战.本研究设计了一种三维碳纳米纤维/氧化石墨烯复合气凝胶(CNF/GOA).氧化石墨... 详细信息

太阳能蒸发是一种可持续的高盐废水处理技术,然而运行中蒸发器表面的盐积累会严重缩短蒸发器的寿命.如何使蒸发器兼具高蒸发效率和良好拒盐性是目前面临的挑战.本研究设计了一种三维碳纳米纤维/氧化石墨烯复合气凝胶(CNF/GOA).氧化石墨烯的引入不仅增强了CNF/GOA的力学性能,同时构建了丰富的分级互连孔道结构,加快了水的传输和盐的扩散,实现了高蒸发速率和良好的拒盐性.此外,通过调控CNF/GOA的浸没深度和孔道结构,抑制了水的热传导损失,降低了水的蒸发焓,在一个太阳照射下实现了3.47 kg m^(-2)h^(−1)的蒸发速率.更重要的是,即使处理高盐水,蒸发器表面也没有产生任何盐结晶.长期实验和户外脱硫废水蒸发实验表明,CNF/GOA具有良好的实际应用前景.

关键词：高盐废水氧化石墨烯蒸发速率太阳照射碳纳米纤维碳气凝胶蒸发效率孔道结构

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植物促生芽孢杆菌中新型脂肪酸通过两组分调控系统OmpS/R和毒素转运蛋白介导的“嗜食同类”机制促进生物被膜的形成

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Science Bulletin 2023年第14期68卷 1500-1504,M0003页

作者：黄蓉李青王丹丹冯海超张楠邵佳慧沈其荣徐志辉张瑞福 Jiangsu Provincial Key Lab of solid Organic Waste Utilization Jiangsu Collaborative Innovation Center of Solid Organic WastesNanjing Agricultural UniversityNanjing 210095China Huaiyin institute of Agricultural Sciences of Xuhuai Region in Jiangsu Jiangsu Academy of Agricultural SciencesHuai’an 223001China National Engineering research Center for Efficient Utilization of Soil and Fertilizer Resources College of Resources and EnvironmentShandong Agricultural UniversityTai’an 271018China State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China Institute of Agricultural Resources and Regional PlanningChinese Academy of Agricultural SciencesBeijing 100081China

当单细胞繁殖进入多细胞水平时,为了应对环境压力,细菌必须进化出维持其群体稳定的作用机制.“嗜食同类”是芽孢杆菌应对环境营养缺乏的一种策略,维持了芽孢杆菌的生存.作为芽孢杆菌的模式种群,枯草芽孢杆菌的“嗜食同类”行为已被广泛... 详细信息

当单细胞繁殖进入多细胞水平时,为了应对环境压力,细菌必须进化出维持其群体稳定的作用机制.“嗜食同类”是芽孢杆菌应对环境营养缺乏的一种策略,维持了芽孢杆菌的生存.作为芽孢杆菌的模式种群,枯草芽孢杆菌的“嗜食同类”行为已被广泛研究,但其他芽孢杆菌的“嗜食同类”机制仍然未知.生物被膜是一种被胞外基质包裹的多细胞群体,维持细菌在自然环境中的生存.本研究报道了由贝莱斯芽孢杆菌SQR9合成的新型次级代谢物杆菌酸(bacillunoic acids,BAs)介导的“嗜食同类”行为及机制,以及它对菌株SQR9生物被膜形成的促进作用.菌株SQR9细胞群体分化为两个亚群,一个亚群合成BAs并通过两组分调控系统OmpS-OmpR激活相应免疫基因bnaAB的表达,而不能合成BAs的亚群对该物质敏感.因而,群体中合成BAs的亚群通过该物质裂解部分不合成BAs的同类,由此释放的胞外DNA促进了生物被膜的形成.该研究结果阐明了菌株SQR9群体中的一些细胞如何牺牲自己,从而使群体中其它细胞有更好的机会在环境中存活下来.因此,菌株SQR9群体受益于“嗜食同类”系统.

关键词：免疫基因细胞群体群体分化调控系统芽孢杆菌生物被膜营养缺乏次级代谢物

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Linear paired electrolysis of furfural to furoic acid at both anode and cathode in a multiple redox mediated system

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Green Energy & environment 2024年第1期9卷 104-113页

作者： Xinxin Li Linchuan Cong Haibo Lin Fangbing Liu Xiangxue Fu Hai-Chao Xu Nan Lin State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin UniversityChangchun 130012JilinChina State Key Laboratory of physical Chemistry of solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005FujianChina

Implementing a new energy-saving electrochemical synthesis system with high commercial value is a strategy of the sustainable development for upgrading the bulk chemicals preparation technology in the ***,we report a multiple redox-mediated linear paired electrolysis system,combining the hydrogen peroxide mediated cathode process with the I2 mediated anode process,and realize the conversion of furfural to furoic acid in both side of the dividedﬂow cell *** reasonably controlling the cathode potential,the undesired water splitting reaction and furfural reduction side reactions are *** the galvanostatic electrolysis,the two-mediated electrode processes have good compatibility,which reduce the energy consumption by about 22%while improving the electronic efﬁciency by about 125%.This system provides a green electrochemical synthesis route with commercial prospects.

关键词： Multiple redox mediated system Linear paired electrolysis Furfural Furoic acid

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CAOSA-extracted lignin improves enzymatic hydrolysis of cellulose

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Green Energy & environment 2024年第7期9卷 1101-1111页

作者： Sen Ma Zheng Li Jonathan Sperry Xing Tang Yong Sun Lu Lin Jian Liu Xianhai Zeng College of Energy State Key Laboratory of Physical Chemistry of Solid SurfacesXiamen UniversityXiamen361102China Fujian Engineering and research Centre of Clean and High-valued Technologies for Biomass Xiamen Key Laboratory of Clean and High-valued Utilization of BiomassXiamen361102China Centre for Green Chemical Science University of AucklandAuckland1142New Zealand

The conversion of biomass into sugar platform compounds is very important for the biorefinery *** is essential to the biomass of the sugar platform,however,the lignin obtained by pretreatment,as a key part of lignocellulose,generally has a passive effect on the enzymatic hydrolysis of cellulose into *** this study,p-TsOH(p-toluenesulfonic acid),DES(Deep eutectic solvent)and CAOSA(cooking with active oxygen and solid alkali)pretreatment ways were used to fraction lignin from bamboo *** CAOSA treatment,the hydrolysis efficiency of the pulp was 95.57%.Moreover,the effect of different treatment methods on lignin properties was studied and the promotion effect of lignin was investigated by adding it to the cellulose enzymatic hydrolysis *** this work,the results showed that CAOSA-extracted lignin with lower D(1.31-1.25)had a better adsorption effect on the enzyme protein.p-TsOH-extracted lignin with a larger S/G ratio enhanced the inhibition of enzymatic *** addition,the presence of-COOHs in lignin could reduce its inhibitory effect on cellulose saccharification.

关键词： Biomass pretreatment CAOSA Cellulose hydrolysis Lignin Enzyme

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Singlet oxygen-dominated peroxymonosulfate activation by layered crednerite for organic pollutants degradation in high salinity wastewater

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Journal of environmental Sciences 2024年第1期135卷 86-96页

作者： Chengji Sui Zixuan Nie Huan Liu Grzegorz Boczkaj Weizhen Liu Lingshuai Kong Jinhua Zhan Key Laboratory for Colloid&Interface Chemistry of Education Ministry Department of ChemistryShandong UniversityJinan 250100China School of environment and Energy Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and RecyclingSouth China University of TechnologyGuangzhou 510006China Gdansk University of Technology Faculty of Civil and Environmental EngineeringDepartment of Sanitary EngineeringG.Narutowicza St.11/1280-233 GdanskPoland EkoTech Center Gdansk University of TechnologyG.Narutowicza St.11/1280-233 GdanskPoland

Advanced oxidation processes have been widely studied for organic pollutants treatment in water,but the degradation performance of radical-dominated pathway was severely inhibited by the side reactions between the anions and radicals,especially in high salinity ***,a singlet oxygen(^(1)O_(2))-dominated non-radical process was developed for organic pollutants degradation in high salinity wastewater,with layered crednerite(CuMnO_(2))as catalysts and peroxymonosulfate(PMS)as *** on the experiments and density functional theory calculations,^(1)O_(2)was the dominating reactive species and the constructed Cu-O-Mn with electron-deficient Mn captured electron from PMS promoting the generation of^(1)O_(2).The rapid degradation of bisphenol A(BPA)was achieved by CuMnO_(2)/PMS system,which was 5-fold and 21-fold higher than that in Mn_(2)O_(3)/PMS system and Cu_(2)O/PMS *** CuMnO_(2)/PMS system shown prominent BPA removal performance under high salinity conditions,prominent PMS utilization efficiency,outstanding total organic carbon removal rate,wide range of applicable pH and good *** work unveiled that the^(1)O_(2)-dominated non-radical process of CuMnO_(2)/PMS system overcame the inhibitory effect of anions in high salinity conditions,which provided a promising technique to remove organic pollutants from high saline wastewater.

关键词： Singlet oxygen Non-radical process High salinity Mixed metal oxides Wastewater treatment

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Mechanical properties of Fe-rich Si alloy from Hamiltonian

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npj Computational Materials 2017年第1期3卷 391-404页

作者： Tetsuo Mohri Ying Chen Masanori Kohyama Shigenobu Ogata Arkapol Saengdeejing Somesh Kumar Bhattacharya Masato Wakeda Shuhei Shinzato Hajime Kimizuka institute for Materials research Tohoku UniversitySendai 980-8577Japan Fracture and Reliability research institute School of EngineeringTohoku UniversitySendai 980-8579Japan research institute of Electrochemical Energy Department of Energy and EnvironmentNational Institute of Advanced Industrial Science and TechnologyIkedaOsaka 563-8577Japan Department of Mechanical Science and Bioengineering Osaka UniversityOsaka 560-8531Japan Center for Elements Strategy Initiative for Structural Materials Kyoto UniversityKyoto 606-8501Japan Computational Structural Materials Design Group Research Center for Structural MaterialsNational Institute for Materials ScienceTsukuba 305-0047Japan

The physical origins of the mechanical properties of Fe-rich Si alloys are investigated by combining electronic structure calculations with statistical mechanics means such as the cluster variation method,molecular dynamics simulation,etc,applied to homogeneous and heterogeneous ***,we examined the elastic properties based on electronic structure calculations in a homogeneous system and attributed the physical origin of the loss of ductility with increasing Si content to the combined effects of magneto-volume and D03 *** a typical example of a heterogeneity forming a microstructure,we focus on grain boundaries,and segregation behavior of Si atoms is studied through high-precision electronic structure *** kinds of segregation sites are identified:looser and tighter *** on the site,different segregation mechanisms are ***,the dislocation behavior in the Fe-Si alloy is investigated mainly by molecular dynamics simulations combined with electronic structure *** solid-solution hardening and softening are interpreted in terms of two kinds of energy barriers for kink nucleation and migration on a screw dislocation ***,the clue to the peculiar work hardening behavior is discussed based on kinetic Monte Carlo simulations by focusing on the preferential selection of slip planes triggered by kink nucleation.

关键词： alloy softening microstructure

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Neutron Spectroscopy Evidence for a Possible Magnetic-Field-Induced Gapless Quantum-Spin-Liquid Phase in a Kitaev Materialα-RuCl3

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Chinese Physics Letters 2022年第5期39卷 87-93页

作者： Xiaoxue Zhao Kejing Ran Jinghui Wang Song Bao Yanyan Shangguan Zhentao Huang Junbo Liao Bo Zhang Shufan Cheng Hao Xu Wei Wang Zhao-Yang Dong Siqin Meng Zhilun Lu Shin-ichiro Yano Shun-Li Yu Jian-Xin Li Jinsheng Wen National Laboratory of solid State Microstructures and Department of Physics Nanjing UniversityNanjing 210093China School of physical Science and Technology and ShanghaiTech Laboratory for Topological Physics ShanghaiTech UniversityShanghai 200031China School of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China Department of Applied Physics Nanjing University of Science and TechnologyNanjing 210094China Helmholtz-Zentrum Berlin fur Materialien und Energie GmbH Hahn-Meitner-Platz 1D-14109 BerlinGermany China institute of Atomic Energy Beijing 102413China School of Engineering and the Built environment Edinburgh Napier UniversityEdinburgh EH105DTUnited Kingdom National Synchrotron Radiation research Center Hsinchu 30077China Collaborative Innovation Center of Advanced Microstructures Nanjing UniversityNanjing 210093China

As one of the most promising Kitaev quantum-spin-liquid(QSL)candidates,α-RuCl_(3)has received a great deal of ***,its ground state exhibits a long-range zigzag magnetic order,which defies the QSL ***,the magnetic order is fragile and can be completely suppressed by applying an external magnetic ***,we explore the evolution of magnetic excitations ofα-RuCl;under an in-plane magnetic field,by carrying out inelastic neutron scattering measurements on high-quality single *** zero field,there exist spin-wave excitations near the M point and a continuum near theΓpoint,which are believed to be associated with the zigzag magnetic order and fractional excitations of the Kitaev QSL state,*** increasing the magnetic field,the spin-wave excitations gradually give way to the continuous *** the verge of the critical fieldμ_(0)H_(c)=7.5 T,the former ones vanish and only the latter ones are left,indicating the emergence of a pure QSL *** further increasing the field strength,the excitations near theΓpoint become more *** following the gap evolution of the excitations near theΓpoint,we are able to establish a phase diagram composed of three interesting phases,including a gapped zigzag order phase at low fields,possibly gapless QSL phase nearμ;H;,and gapped partially polarized phase at high *** results demonstrate that an in-plane magnetic field can driveα-RuCl;into a long-sought QSL state near the critical field.

关键词： field excitation zigzag

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Theory and algorithms for the excited states of large molecules and molecular aggregates

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Science China Chemistry 2013年第9期56卷 1267-1270页

作者： LIANG WanZhen WU Wei State Key Laboratory of physical Chemistry of solid Surfaces Collaborative Innovation Center of Chemistry for Energy MaterialsFujian Provincial Key Laboratory of Theoretical and Computational Chemistryand Department of ChemistryCollege of Chemistry and Chemical EngineeringXiamen University

This project aims to attack the frontiers of electronic structure calculations on the excited states of large molecules and molecular aggregates by developing novel theoretical and computational methods. The methodology development is especially based on the time-dependent density functional theory (TDDFT) and valence bond (VB) theory, and is expected to be computationally effective and accurate as well. research works on the following related subjects will be performed: (1) The analytical energy-derivative approaches for electronically excited state within TDDFT will be developed to reduce bypass the computational costs in the calculation of molecular excited-state properties. (2) The ab initio methods for electronically excited state based on VB theory and hybrid TDDFT-VB method will be developed to overcome the limitations of current TDDFT in simulating photophysics and photochemistry. (3) For larger aggregates, neither ab initio methods nor TDDFT is applicable. We intend to build the effective model Hamiltonian by developing novel theoretical and computational methods to calculate the involved microscopic physical parameters from the first-principles methods. The constructed effective Hamiltonian is then used to describe the excitonic states and excitonic dynamics of the natural or artificial photosynthesized systems, organic or inorganic photovoltaic cell. (4) The condensed phase environment is taken into account by combining the developed theories and algorithms based on TDDFT and VB with the polarizable continuum solvent models (PCM), molecular mechanism (MM), classical electrodynamics (ED) or molecular dynamics (MD) theory. (5) Highly efficient software packages will be designed and developed.

关键词： molecular aggregates excited state effective model Hamiltonian time-dependent density functional theory (TDDFT) valence bond (VB) theory multiscale models

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Comparison study of phosphorus adsorption on different waste solids:Fly ash,red mud and ferric–alum water treatment residues

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Journal of environmental Sciences 2016年第12期28卷 79-86页

作者： Ying Wang Yange Yu Haiyan Li Chanchan Shen School of environment Beijing Normal University Beijing Engineering research Center of Sustainable Urban Sewage System Construction and Risk Control Beijing University of Civil Engineering and Architecture

The adsorption of phosphorus （P） onto three industrial solid wastes （fiy ash, red mud and ferric-alum water treatment residual （FAR）） and their modified materials was studied systematically ufa batch experiments. Compared with two natural adsorbents （zeolite and diatomite）, three solid wastes possessed a higher adsorption capacity for P because of the higher Fe, A1 and Ca contents. After modification （i.e., the fly ash and red mud modified by FeC13 and FARs modified by HC1）, the adsorption capacity increased, especially for the modified red mud, where more Fe bonded P was observed. The P adsorption kinetics can be satisfactorily fitted using the pseudo-second-order model. The Langmuir model can describe well the P adsorption on all of the samples in our study, pH and dissolved organic matter （DOM） are two important factors for P adsorption. Under neutral conditions, the maximum adsorption amount on the modified materials was observed. With the deviation from pH 7, the adsorption amount decreased, which resulted from the change of P species in water and surface charges of the adsorbents. The DOM in water can promote P adsorption, which may be due to the promotion effects of humic-Fe（A1） complexes and the pH buffer function exceeds the depression of competitive adsorption.

关键词： Phosphorus Adsorption solid wastes DOM

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