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Adsorption and biodegradation of three selected endocrine disrupting chemicals in river-based artificial groundwater recharge with reclaimed municipal wastewater

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Journal of Environmental Sciences 2015年第5期27卷 154-163页

作者： Weifang Ma chao nie Bin Chen Xiang Cheng Xiaoxiu Lun Fangang Zeng College of Environmental Science and Engineering Beijing Forestry University School of Environment and Natural Resource Renmin University of China

Endocrine disrupting chemical（EDC） pollution in river-based artificial groundwater recharge using reclaimed municipal wastewater poses a potential threat to groundwater-based drinking water supplies in Beijing, China. Lab-scale leaching column experiments simulating recharge were conducted to study the adsorption, biodegradation, and transport characteristics of three selected EDCs： 17β-estradiol（E2）, 17α-ethinylestradiol（EE2） and bisphenol A（BPA）. The three recharge columns were operated under the conditions of continual sterilization recharge（CSR）, continual recharge（CR）, and wetting and drying alternative recharge（WDAR）. The results showed that the attenuation effect of the EDCs was in the order of WDAR 〉 CR 〉 CSR system and E2 〉 EE2 〉 BPA, which followed first-order kinetics. The EDC attenuation rate constants were 0.0783, 0.0505, and 0.0479 m-1 for E2, EE2 and BPA in the CR system, respectively. The removal rates of E2, EE2, and BPA in the CR system were 98%, 96% and 92%, which mainly depended on biodegradation and were affected by water *** the CR system, the concentrations of BPA, EE2, and E2 in soil were 4, 6 and 10 times higher than in the WDAR system, respectively. According to the DGGE fingerprints, the bacterial community in the bottom layer was more diverse than in the upper layer, which was related to the EDC concentrations in the water-soil system. The dominant group was found to be proteobacteria, including Betaproteobacteria and Alphaproteobacteria, suggesting that these microbes might play an important role in EDC degradation.

关键词： Endocrine disrupting chemicals Adsorption Biodegradation Artificial groundwater recharge Bacterial community

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17α-Ethynylestradiol biodegradation in different river-based groundwater recharge modes with reclaimed water and degradation-associated community structure of bacteria and archaea

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Journal of Environmental Sciences 2018年第2期30卷 51-61页

作者： Weifang Ma Jiaji Sun Yangyao Li Xiaoxiu Lun Dan Shan chao nie Miaomiao Liu College of Environmental Science and Engineering Beijing Forestry University Beijing 100083 China Friendship Center for Environmental Protection Beijing 100029 China Department of Civil and Environmental Engineering university of Illinois at Urbana-Champaign Urbana IL 61801-2352 USA

This study investigated 17α-ethynylestradiol（EE2） biodegradation process and primary metabolic pathways associated with community structures of microorganism during groundwater recharge using reclaimed water. The attenuation rate is 1.58 times higher in wetting and drying alternative recharge（WDAR） than in continual recharge（CR）. The primary biotransformation pathways of EE2 in WDAR system began with the oxidation of C-17 on ring D to form a ketone group, and D-ring was subsequently hydroxylated and cleaved. In the CR system, the metabolic pathway changed from the oxidation of C-17 on ring D to hydroxylation of C-4 on ring A, and ring A or B subsequently cleaved; this transition was related to DO, and the microbial community structure. Four hundred fifty four pyrosequencing of 16 s r RNA genes indicated that the bacterial communities in the upper layer of the WDAR system were more diverse than those found in the bottom layer of the CR system; this result was reversed for archaea. Unweighted Uni Frac and taxonomic analyses were conducted to relate the change in bacterial community structure to the metabolic pathway. Microorganism community diversity and structure were related to the concentrations of dissolved oxygen, EE2 and its intermediates in the system. Five known bacterial classes and one known archaeal class, five major bacterial genera and one major archaeal genus might be involved in EE2 degradation. The findings of this study provide an understanding of EE2 biodegradation in groundwater recharge areas under different recharging modes and can facilitate the prediction of the fate of EE2 in underground aquifers.

关键词： EE2 Biodegradation Groundwater recharge Microbial community and diversity Metabolic intermediates

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Experimental and Theoretical Study on CHF of a Ultra-Supercritical Circulating Fluidized Bed Boiler Water-Wall Tube at near-Critical Pressures

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Journal of Thermal Science 2023年第1期32卷 166-182页

作者： WANG Wenyu MA Zhan QING Hao nie chao YANG Haoyu BI Lingfeng YANG Dong PAN Wenxiao State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049China Department of Mechanical Engineering University of Wisconsin-Madison1513 University AveMadisonWI 53706USA

The experimental and theoretical research on the critical heat flux(CHF)in a uniformly heated water-wall tube of the efficient ultra-supercritical circulating fluidized bed(USCFB)boiler has been *** particular,the experimental pressure varies from 18 MPa to 21 MPa,which is from 0.814Pcr–0.95Pcr(Pcr:critical pressure).The mass flux varies from 310 kg·m^(–2)·s^(–1)to 550 kg·m^(–2)·s^(–1).The inlet sub-cooling temperatures vary from 5°C to 10°*** material of the tube is *** experimental investigation,the near critical pressure CHF test data of water are *** find that the CHF mainly occurs when the vapor qualities are less than 0.4,and it occurs earlier(at lower vapor quality)when the pressure is closer to 22.115 MPa or the mass flux is *** the experimental data,a correlation function for the CHF is established via regression and machine *** established via machine learning greatly improved the regression *** study the CHF phenomenon mechanically,a theoretical model is established based on the near-surface bubble crowding model describing the DNB-type *** the development of the CHF model,the friction resistance coefficient is determined according to our test *** comparison with different experimental results,the near-surface bubble crowding model is well suited to describe DNB-type *** calculation results of the model can provide reference for the optimal design of the USCFB boiler.

关键词： circulating fluidized bed critical heat flux near-critical pressure bubble crowding machine learning

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CIVB flashback analysis of hydrogen flame based on azimuthal vorticity at mixing zone exit

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Science China(Technological Sciences) 2014年第12期57卷 2466-2474页

作者： TIAN Xiao Jing XING Shuang Xi CUI Yu Feng FANG Ai Bing nie chao Qun Key Laboratory of Advanced Energy and Power Institute of Engineering Thermophysics Chinese Academy of Sciences University of Chinese Academy of Sciences

Swirl-premixed combustion systems exhibit potential to meet future regulations on pollution emissions. However, combustion induced vortex breakdown(CIVB) flashback is frequently observed in these systems, especially for high hydrogen content fuel. In this study, a swirl-premixed burner with diverging centerbody was used to investigate CIVB flashback based on azimuthal vorticity at mixing zone exit. Through 2D axisymmetric model, it was found that there was a maximal azimuthal vorticity at mixing zone exit for each equivalence ratio. The physical meaning of these maximal azimuthal vorticity values was the minimally required azimuthal vorticity to trigger CIVB flashback. At the same time, the required azimuthal vorticity declined with the increase of equivalence ratio since turbulent burning velocity started to control flashback. Nevertheless, azimuthal vorticity offered by heat release increased with the increase of equivalence ratio, which promoted flame propagating upstream continually.

关键词： azimuthal vorticity mixing zone exit premixed hydrogen flame CIVB flashback

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A nonlinear creep damage model for gelled waxy crude

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Petroleum Science 2022年第4期19卷 1803-1811页

作者： Hong-Ying Li Qing-Bo Xie Hao Sun Wei Guo Feng Yan Qing Miao chao-Fei nie Yu Zhuang Qian Huang Jin-Jun Zhang National Engineering Laboratory for Pipeline Safety/MOE Key Laboratory of Petroleum Engineering/Bejing Key Laboratory of Urban Oil&Gas Distribution Technology/China Universityof Petroleum Beijing102249China PipeChina Pipeline R&DCenter Langfang065000China Jinan Urban Planning and Design Institute Jinan250101China

Yielding behaviors of waxy crude oil is one of the key issues of flow assurance challenges. The yielding of waxy crude under constant stress is actually a creep process of strain accumulation to structural failure,to describe the process completely and accurately is the basis of numerical simulation of restart process of the pipeline. The creep and yield behaviors of two gelled waxy crudes were investigated experimentally under different constant applied stresses. The results clearly show that the creep process of waxy crude is related to the applied stress and time. The greater the applied stress, and the longer the loaded time, the more obvious the nonlinear features. Based on the fractional calculus theory, a fractional viscous element was developed to describe the decelerated and steady creep process of gelled waxy crude. On the basis of the damage theory, an elastic damage element was proposed to describe the accelerated creep after the yielding. According to the idea of mechanical analogy, a nonlinear creep model was established by a fractional viscous element, an elastic damaged element, and an elastic element in series, which can accurately describe the whole creep and yielding process of gelled waxy crude.

关键词： Waxy crude oil Rheology Yield Creep Constitutive model Mechanical analogy

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Plasma Extracellular Vesicle MicroRNA Analysis of Alzheimer’s Disease Reveals Dysfunction of a Neural Correlation Network

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Research 2023年第4期2023卷 689-699页

作者： Yuzhe Sun Zhen Hefu Benchao Li Wang Lifang Song Zhijie Li Zhou Yan Deng Liu Zhili Jiahong Ding Tao Li Wenwei Zhang nie chao Shuang Rong Department of Nutrition and Food Hygiene School of Public HealthMedical CollegeWuhan University of Science and TechnologyWuhanChina BGI-Shenzhen ShenzhenChina Shenzhen Key Laboratory of Neurogenomics BGI-ShenzhenShenzhen 518120China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China.

Small extracellular vesicle(sEV)is an emerging source of potential biomarkers of Alzheimer's disease(AD),but the role of microRNAs(miRNAs)in sEV is not well *** this study,we conducted a comprehensive analysis of sEV-derived miRNAs in AD using small RNA sequencing and coexpression network *** examined a total of 158 samples,including 48 from AD patients,48 from patients with mild cognitive impairment(MCI),and 62 from healthy *** identified an miRNA network module(M1)that was strongly linked to neural function and showed the strongest association with AD diagnosis and cognitive *** expression of miRNAs in the module was decreased in both AD and MCI patients compared to *** analysis revealed that M1 was highly preserved in the healthy control group but dysfunctional in the AD and MCI groups,suggesting that changes in the expression of miRNAs in this module may be an early response to cognitive decline prior to the appearance of AD *** further validated the expression levels of the hub miRNAs in M1 in an independent *** functional enrichment analysis showed that 4 hub miRNAs might interact with a GDF11-centered network and play a critical role in the neuropathology of *** summary,our study provides new insights into the role of sEV-derived miRNAs in AD and suggests that M1 miRNAs may serve as potential biomarkers for the early diagnosis and monitoring of AD.

关键词： network analysis. diagnosis

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Tailoring the oxygen concentration in Ge-Sb-O alloys to enable femtojoule-level phase-change memory operations

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Materials Futures 2022年第4期1卷 174-182页

作者： Jiang-Jing Wang Xiaozhe Wang Yudong Cheng Jieling Tan chao nie Zhe Yang Ming Xu Xiangshui Miao Wei Zhang En Ma Center for Alloy Innovation and Design(CAID) State Key Laboratory for Mechanical Behavior of MaterialsXi’an Jiaotong UniversityXi’an 710049People’s Republic of China School of Integrated Circuits Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China

Chalcogenide phase-change materials(PCMs),in particular,the flagship Ge2Sb2Te5(GST),are leading candidates for advanced memory ***,GST in conventional devices suffer from high power consumption,because the RESET operation requires melting of the crystalline GST ***,we have developed a conductive-bridge scheme for low-power phase-change application utilizing a self-decomposed Ge-Sb-O(GSO)*** this work,we present thorough structural and electrical characterizations of GSO thin films by tailoring the concentration of oxygen in the phase-separating GSO *** elucidate a two-step process in the as-deposited amorphous film upon the introduction of oxygen:with increasing oxygen doping level,germanium oxides form first,followed by antimony *** enable the conductive-bridge switching mode for femtojoule-level RESET energy,the oxygen content should be sufficiently low to keep the antimony-rich domains easily crystallized under external electrical *** work serves as a useful example to exploit alloy decomposition that develops heterogeneous PCMs,minimizing the active switching volume for low-power electronics.

关键词： phase-change memory amorphous phase low-power conductive-bridge decomposition

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Study of buffer and epitaxy technology in two-step growth of aluminium nitride

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Science China(Technological Sciences) 2008年第11期51卷 1881-1885页

作者： LIU QiJia ZHANG Rong XIE ZiLi LIU Bin XU Feng YAO Jing nie chao XIU XiangQian HAN Ping ZHENG YouDou GONG HaiMei Jiangsu Provincial Key Laboratory of Advanced Photonic and Electronic Materials Department of PhysicsNanjing UniversityNanjing 210093China Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai 200083China

AlN (aluminium nitride) films were prepared by metalorganic chemical vapor depo- sition (MOCVD) on c-plane sapphire (α-Al2O3) substrates. By means of studying the traces of in-situ optical reflectivity, it was found that the AlN nucleation layer showed a specific (0001) lattice orientation, which differed from the GaN nucleation layer on (0001) sapphire substrates. The AlN buffer suffered the compressive stress at the initial stage of nucleation. And the compressive strain was relaxed gradually along with the thickness of buffer increasing and consequently annealing. Optical transmission spectra revealed that in the process of growing AlN epilayers, higher V/III ratio could improve the crystal quality but reduce the growth rates. In addition, proper doping of silane (SiH4) could improve the surface morphology of AlN film.

关键词： AlN MOCVD optical reflectivity XRD optical transmission spectra

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Effect of cryogenic treatment on membranebased binding strength of DLC film/quenched W9 high-speed steel

Effect of cryogenic treatment on membranebased binding stren...

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2014中国功能材料科技与产业高层论坛

作者： ZHAO Yang nie chao-Yin nie Yan-Zhong LIU Xiao-Dong GONG Xiao-Ling Faculty of Materials and Energy Southwest University

The 2μm thick DLC film was deposited by unbalanced magnetron sputtering technique on quenched W9 high-speed steel substrate,and the membrane-based system was treated with cryogenic treatment at-196℃for 30 *** rockwell hardness tester,nano scratch tester,EDS,SEM and XRD,the membrane-based binding strength of DLC film/highspeed steeLmain elements’line distribution of membrane-based section,and substrate organizational structure were respectively detected before and *** results show that membrane-based binding force is approximately increased from1200mN to 1400mN through *** is most mainly because the quenched high-speed steel substrate is occurred to martensitic transformation and martensitic decomposition in cryogenic process,which leads to the increase of substrate grain boundary,at warmed stage of cryogenic providing more short-range channels for DLC film’s C element to diffuse to the substrate surface,and more place for segregation along grain boundary with the newly formed carbides having a pinning effect on the substrate.

关键词： DLC film Cryogenic Membrane binding strength C element diffusion Increasing of grain boundary

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利用连续多模态特性探索的自适应Kriging模型构建方法

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计算机辅助设计与图形学学报 2016年第9期28卷 1598-1604页

作者：李志华聂超龚友平杭州电子科技大学机械工程学院杭州310018

为了高效率地构建高精度的代理模型,提出一种利用连续多模态特性探索的自适应Kriging模型构建方法.首先在获得一个初始Kriging模型后,利用留一交叉验证策略计算出代理模型的精度;然后利用相对误差准则,从样本库中挑选出误差最大的样本点... 详细信息

为了高效率地构建高精度的代理模型,提出一种利用连续多模态特性探索的自适应Kriging模型构建方法.首先在获得一个初始Kriging模型后,利用留一交叉验证策略计算出代理模型的精度;然后利用相对误差准则,从样本库中挑选出误差最大的样本点;再通过泰勒级数展开式快速获得新样本点及其近似响应值;如此不断地更新样本库及Kriging模型,最终使模型精度达到预定要求.对2个数学算例和1个工程实例进行了应用分析,结果表明,该方法能够以较快的速度得到较高精度的Kriging模型.

关键词： Kriging模型留一交叉验证策略相对误差准则泰勒级数展开式

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