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Frontiers of Environmental Science & Engineering 2015年第5期9卷 850-860页

作者： rongfang yuan Key Laboratory of Educational Ministry for High Efficient Mining and Safety in Metal Mine University of Science and Technology Beijing Beijing 100083 China Department of Environmental Engineering Scl~ool of Civil and-Environmental Engineering University of Science and Technology Beijing Beijing 100083 China

The effect of ion-doping on TiO2 nanotubes were investigated to obtain the optimal TiO2 nanotubes for the effective decomposition of humic acids （HA） through O3/UV/ion-doped TiO2 process. The experimental results show that changing the calcination temperature, which changed the weight fractions of the anatase phase, the average crystallite sizes, the Brunauer-Emmett-Teller sur- face area, and the energy band gap of the catalyst, affected the photocatalytic activity of the catalyst. The ionic radius, valence state, and configuration of the dopant also affected the photocatalytic activity. The photocatalytic activities of the catalysts on HA removal increased when Ag＋, AP＋, Cu2＋, Fe3＋, V5 ＋, and Zn2＋ were doped into the TiO2 nanotubes, whereas such activities decreased as a result of Mn2＋- and Ni2＋-doping. In the presence of 1.0 at.% Fe3＋- doped TiO2 nanotubes calcined at 550℃, the removal efficiency of HA was 80% with a pseudo-first-order rate constant of 0.158 min-. Fe3＋ in TiO2 could increase the generation of OH, which could remove HA. However, Fe3＋ in water cannot function as a shallow trapping site for electrons or holes.

关键词： TiO2 nanotubes ion-doping humic acids,pseudo-first-order mechanism

Mechanisms for simultaneous ozonation of sulfamethoxazole and natural organic matters in secondary effluent from sewage treatment plant

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Frontiers of Environmental Science & Engineering 2021年第4期15卷 299-310页

作者： Xinshu Liu Xiaoman Su Sijie Tian Yue Li rongfang yuan Beijing Key Laboratory of Resource-oriented Treatment of Industrial Pollutants Department of Environmental Science and EngineeringUniversity of Science and Technology BeijingBeijing100083China

Sulfamethoxazole(SMX)is commonly detected in wastewater and cannot be completely decomposed during conventional treatment ***(O_(3))is often used in water *** study explored the influence of natural organic matters(NOM)in secondary effluent of a sewage treatment plant on the ozonation pathways of *** changes in NOM components during ozonation were also *** was primarily degraded by hydrolysis,isoxazole-ring opening,and double-bond addition,whereas hydroxylation was not the principal route given the low maximum abundances of the hydroxylated products,with m/z of 269 and *** hydroxylation process occurred mainly through indirect oxidation because the maximum abundances of the products reduced by about 70%after the radical quencher was added,whereas isoxazole-ring opening and double-bond addition processes mainly depended on direct oxidation,which was unaffected by the *** mainly affected the degradation of micropollutants by consuming•OH rather than O_(3)molecules,resulting in the 63%–85%decrease in indirect oxidation *** NOM in the effluent were also degraded simultaneously during ozonation,and the components with larger aromaticity were more likely degraded through direct *** dependences of the three main components of NOM in the effluent on indirect oxidation followed the sequence:humic-like substances>fluvic-like substance-s>protein-like *** study reveals the ozonation mechanism of SMX in secondary effluent and provides a theoretical basis for the control of SMX and its degradation products in actual water treatment.

关键词： Sulfamethoxazole Ozonation Natural organic matters Secondary effluent Degradation mechanism

Biodegradation of geosmin in drinking water by novel bacteria isolated from biologically active carbon

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Journal of Environmental Sciences 2011年第5期23卷 816-823页

作者： Beihai Zhou rongfang yuan Chunhong Shi Liying Yu Junnong Gu Chunlei Zhang Department of Environmental Engineering University of Science and Technology Beijing Beijing 100083 China. E-mail: zhoubeihai@ *** Water Quality Monitoring Center Beijing Waterworks Group Beijing 100085 China

Three strains of Gram-negative bacteria capable of removing geosmin from drinking water were isolated from biologically active carbon and identified to be Chryseobacterium sp., Sinorhizobium sp. and Stenotrophomonas sp. based on physio-biochemistry analysis and 16S rRNA gene sequence analysis. Removal efficiencies of 2 mg/L geosmin in mineral salts medium were 84.0%, 80.2% and 74.4% for Chryxeobacterium sp., Sinorhizobium sp. and Stenotrophomonas sp., respectively, while removal efficiencies of 560 ng/L geosmin in filter influent were 84.8%, 82.3% and 82.5%, respectively. The biodegradation of geosmin was determined to be a pseudo first-order reaction, with rate constants at 2 mg/L and 560 ng/L being 0.097 and 0.086 day-1, 0.089 and 0.084 day-1, 0.074 and 0.098 day-1 for the above mentioned degraders, respectively. The biomass of culture in the presence of geosmin was much higher than that in the absence of geosmin.

关键词： geosmin biodegradation pseudo first-order reaction Chryseobacterium sp. Sinorhizobium sp. Stenotrophomonas sp.

Biodegradation of 2-methylisoborneol by bacteria enriched from biological activated carbon

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Frontiers of Environmental Science & Engineering 2012年第5期6卷 701-710页

作者： rongfang yuan Beihai ZHOU Chunhong SHI Liying YU Chunlei ZHANG Junnong GU Department of Environmental Engineering University of Science and Technology BeijingBeijing 100083China Water Quality Monitoring Center Beijing Waterworks GroupBeijing 100085China

One of the most common taste and odour compounds （TOCs） in drinking water is 2-methylisobor- neol （2-MIB） which cannot be readily removed by conventional water treatments. Four bacterial strains for degrading 2-MIB were isolated from the surface of a biological activated carbon filter, and were characterized as Micrococcus spp., Flavobacterium spp., Brevibacterium spp. and Pseudomonas spp. based on 16S rRNA analysis. The removal efficiencies of 2-MIB with initial concentra- tions of 515 ng.L i were 98.4%, 96.3%, 95.0%, and 92.8% for Micrococcus spp., Flavobacterium spp., Brevibacter- ium spp. and Pseudomonas spp., respectively. These removal efficiencies were slightly higher than those with initial concentration at 4.2 mg. L~ （86.1%, 84.4%, 86.7% and 86.0%, respectively）. The kinetic model showed that biodegradation of 2-MIB at an initial dose of 4.2 mg. L1 was a pseudo-first-order reaction, with rate constants of 0.287, 0.277, 0.281, and 0.294d-1, respectively. These degraders decomposed 2-MIB to form 2-methylenebor- nane and 2-methyl-2-bornane as the products.

关键词： 2-methylisoborneol (2-MIB) biodegradation,2-methylenebornane 2-methyl-2-bornane pseudo-first-order reaction

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煤岩瓦斯动力灾害风险智能判识与融合预测

能源与环保 2024年第5期46卷 71-77页

作者：罗卫东杨乘胡金春袁荣方赵喜宇贵州能源产业研究院有限公司贵州贵阳550025 贵州林东煤业发展有限责任公司龙凤煤矿贵州毕节551700

煤岩瓦斯动力灾害对矿井安全生产造成了极大威胁,由于诱发因素众多,其内在的致灾机理难以被有效探明。为实现煤岩瓦斯动力灾害风险的智能识别与预测,建立了基于CNN的煤岩瓦斯动力灾害风险智能判识与融合预测模型。模型中采用Box-plot与M... 详细信息

煤岩瓦斯动力灾害对矿井安全生产造成了极大威胁,由于诱发因素众多,其内在的致灾机理难以被有效探明。为实现煤岩瓦斯动力灾害风险的智能识别与预测,建立了基于CNN的煤岩瓦斯动力灾害风险智能判识与融合预测模型。模型中采用Box-plot与MI方法进行数据清洗,并利用GRA方法建立包含10个风险因素在内的煤岩瓦斯动力灾害的指标体系,通过PCA方法对数据进行降维处理后,输入至CNN模型中进行融合与预测。通过与ANN、BP、RF、SVM模型的对比分析表明,基于CNN的煤岩瓦斯动力灾害风险智能判识与融合预测模型具有更高的准确性,同时此模型的收敛速度更快,验证了此模型在实际工程中具有更可靠的工程价值。

关键词：煤岩瓦斯动力灾害卷积神经网络预测模型风险识别深度学习

The origin and evolution of Earth's nitrogen

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National Science Review 2024年第06期11卷 56-75页

作者： yuan Li State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences Bayerisches Geoinstitut Universit?t Bayreuth

Nitrogen is a vital element for life on Earth. Its cycling between the surface(atmosphere + crust) and the mantle has a profound influence on the atmosphere and climate. However, our understanding of the origin and evolution of Earth's nitrogen is still incomplete. This review presents an overview of the current understanding of Earth's nitrogen budget and the isotope composition of different reservoirs, laboratory constraints on deep nitrogen geochemistry, and our understanding of the origin of Earth's nitrogen and the deep nitrogen cycle through plate subduction and volcanism. The Earth may have acquired its nitrogen heterogeneously during the main accretion phase, initially from reduced, enstatite-chondrite-like impactors,and subsequently from increasingly oxidized impactors and minimal CI-chondrite-like materials. Like Earth's surface, the mantle and core are also significant nitrogen reservoirs. The nitrogen abundance and isotope composition of these three reservoirs may have been fundamentally established during the main accretion phase and have been insignificantly modified afterwards by the deep nitrogen cycle, although there is a net nitrogen ingassing into Earth's mantle in modern subduction zones. However, it is estimated that the early atmosphere of Earth may have contained ～1.4 times the present-day atmospheric nitrogen(PAN),with ～0.4 PAN being sequestered into the crust via biotic nitrogen fixation. In order to gain a better understanding of the origin and evolution of Earth's nitrogen, directions for future research are suggested.

关键词： nitrogen isotopes silicate Earth atmosphere magma ocean

Robustness of the octupole collectivity in 144Ba within the cranking covariant density functional theory in 3D lattice

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Nuclear Science and Techniques 2024年第8期35卷 124-131页

作者： Ze‑Kai Li yuan‑yuan Wang Mathematics and Physics Department North China Electric Power UniversityBeijing 102206China Hebei Key Laboratory of Physics and Energy Technology North China Electric Power UniversityBaoding 071000China

The octupole deformation and collectivity in octupole double-magic nucleus 144Ba are investigated using the Cranking covariant density functional theory in a three-dimensional lattice *** reduced B(E3)transition probability is implemented for the first time in semiclassical approximation based on the microscopically calculated electric octupole *** available data,including the I-ωrelation and electric transitional probabilities B(E2)and B(E3)are well ***,it is shown that the ground state of 144Ba exhibits axial octupole and quadrupole deformations that persist up to high spins(I≈24h).

关键词： Octupole collectivity Cranking covariant density functional theory Rotational spectrum Electric transitional probabilities

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生物活性炭工艺深度处理丹江口水库水的中试

环境科学研究 2015年第10期28卷 1617-1623页

作者：袁蓉芳周北海邬晓东顾军农张磊北京科技大学土木与环境工程学院环境工程系北京100083 北京市环境保护监测中心北京100048 北京市自来水集团水质监测中心北京100085

活性炭过滤是饮用水深度处理的重要工艺,其中滤速、炭层高度、温度和炭龄是影响活性炭滤池运行效果的关键因素.以丹江口水库水为处理对象,以混凝-沉淀-砂滤出水作为炭滤池进水,以高锰酸盐指数和UV254去除率为评价指标,考察2011年4月—2... 详细信息

活性炭过滤是饮用水深度处理的重要工艺,其中滤速、炭层高度、温度和炭龄是影响活性炭滤池运行效果的关键因素.以丹江口水库水为处理对象,以混凝-沉淀-砂滤出水作为炭滤池进水,以高锰酸盐指数和UV254去除率为评价指标,考察2011年4月—2013年5月取自北京某水厂的新炭、1年炭、3年炭和5年炭（2011年5月时炭龄）对水中有机物的去除效果.结果表明,随着滤速的增大,有机物去除率降低;活性炭炭柱滤速为8 m/h时,高锰酸盐指数和UV254去除率分别为41.9%和41.2%,能够获得较好的处理效果.UV254去除率随总炭层高度的增大而增大.随着炭层高度的增加,单位高度活性炭滤料对UV254的去除率降低.夏季高温期,1年炭对高锰酸盐指数和UV254的去除率分别为44.2%~57.4%和38.5%~53.1%,高于其在冬季低温期的去除率（38.9%~51.1%和31.7%~45.5%）.活性炭在使用初期,主要依靠吸附作用去除有机物;随着使用年限的增长,活性炭的生物载体作用日益明显,生物作用占主导地位,炭龄对有机物去除效果的影响变小,不同炭龄活性炭的处理效果差异不大,可适当延长活性炭的使用年限,降低处理成本.

关键词：生物活性炭滤速温度炭龄丹江口水库

Collective Molecular Machines: Multidimensionality and Reconfigurability

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Nano-Micro Letters 2024年第8期16卷 309-340页

作者： Bin Wang yuan Lu Department of Chemical Engineering Tsinghua UniversityBeijing 100084People’s Republic of China Key Laboratory of Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084People’s Republic of China

Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical *** the last 60 years,designing molecular structures capable of generating unidirectional mechanical motion at the nanoscale has been the topic of intense *** progress has been made,attributed to advances in various fields such as supramolecular chemistry,biology and nanotechnology,and ***,individual molecular machines are only capable of producing nanometer work and generally have only a single *** order to address these problems,collective behaviors realized by integrating several or more of these individual mechanical units in space and time have become a new *** this review,we comprehensively discuss recent developments in the collective behaviors of molecular *** particular,collective behavior is divided into two *** is the appropriate integration of molecular machines to efficiently amplify molecular motions and deformations to construct novel functional *** other is the construction of swarming modes at the supramolecular level to perform nanoscale or microscale *** discuss design strategies for both modes and focus on the modulation of features and ***,in order to address existing challenges,the idea of transferring experience gained in the field of micro/nano robotics is presented,offering prospects for future developments in the collective behavior of molecular machines.

关键词： Molecular machines Collective control Collective behaviors DNA Biomolecular motors

Global adaptive output-feedback tracking with prescribed performance for uncertain nonlinear systems

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Science China(Information Sciences) 2024年第5期67卷 150-164页

作者： yuan WANG Yungang LIU School of Control Science and Engineering Shandong University

At present, one typical control strategy for guaranteeing transient and steady-state performance is funnel control and prescribed performance control. The strategy features completely discarding the system nonlinearities, even if they are completely known and available. Such an intrinsic feature requires the controller to produce a larger control effect to eliminate the negative impact caused by the high nonlinearities, leading to a conservative controller. In this paper, we fully take advantage of known information on nonlinearities in control design, instead of completely discarding it as done in funnel control. Particularly, we leverage adaptive techniques(i.e., high-gain dynamic compensation) to deal with unknown system nonlinearities. Meanwhile, we integrate the tools of output feedback, tracking control, and the performance *** such, an adaptive output-feedback scheme is developed for global tracking with spatiotemporal performance specifications: arbitrarily given tracking accuracy and accuracy-ensured time. A simulation example supports the developed approach.

关键词： uncertain nonlinear systems output feedback prescribed performance unknown control direction dynamic high gain global tracking