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Free cupric ions in contaminated agricultural soils around a copper mine in eastern Nanjing City, China

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Journal of Environmental Sciences 2006年第5期18卷 927-931页

作者： LUO Xiao-san ZHOU dong-mei WANG Yu-jun State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 China Graduate School of the Chinese Academy of Sciences Beijing 100039 China

To determine the environmental free metal ion activity was a recent hot issue. A method to measure low-level free cupric ion activity in soil solution extracted with 0.01 mol/L KNO3 was developed by using cupric ion-selective electrode （ISE） and calibrating with Cu-buffer solution. Three copper buffers including iminodiacetic acid （IDA）, ethylenediamine （EN）, and glycine （Gly） were compared for calibrating the Cu-ISE curves in the range of free cupric ions （pCu^2＋） 7-13. The Cu-EN buffer showed the best electrode response and thus was applied as the calibration buffer. The pCu^2＋ of 39 contaminated agricultural soils around a copper mine was measured, ranging from 5.03 to 9.20. Most Cu in the soil solutions was found to be complexed with dissolved soil organic matters, averaging 98.1%. The proportion of free Cu^2＋ ions in the soil solutions decreased with the increasing of solution pH. Soluble Cu and free Cu^2＋ ions concentrations were analyzed by multiple linear regressions to evaluate the effects of soil properties on metal levels and speciation. The results showed that soil solution pH was the most significant factor influencing pCu^2＋（with R^2 value of 0.76）, while not important for the soluble Cu concentration.

关键词： copper ion selective electrode (Cu-ISE) free metal ion activity soil solution metal speciation bioavailability

Infrared Polarization and Beaming Effect for BL Lac Objects

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Chinese Physics Letters 2001年第5期18卷 708-710页

作者： mei dong-Cheng XIE Guang-Zhong Yunnan Astronomical Observatory Chinese Academy of SciencesKunming 650011 The National Astronomical Observatories Chinese Academy of Sciences Yunnan Astrophysics Center Yunnan UniversityKunming 650091

With the idea of the beaming models,we derive a relation between the observed polarization and Doppler-corrected magnitude,that is,the observed polarization is in anti-correlation with the Doppler-corrected *** use of the infrared data observed simultaneously by Impey et al.[***.200(1982)19;209(1984)245]and Holmes et al.[ibid.210(1984)961]we found that(1)there is a significant correlation between the observed maximum polarization and Doppler-corrected magnitude but the polarization is not in anti-correlation with the Doppler corrected magnitude;(2)the maximum infrared polarization is strongly correlated with the maximum optical *** conclusion is that the infrared polarization depends only on the degree of ordering of the magnetic field in the synchotron emission regions and not on the beaming *** infrared and optical emissions originate from the synchrotron radiation.

关键词： polarization optical Soc

Interference Pattern of Density-Density Correlation for Incoherent Atoms with Vortices Released from an Optical Lattice

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Chinese Physics Letters 2011年第1期28卷 26-29页

作者： XU Zhi-Jun ZHANG dong-mei LIU Xia-Yin College of Science Zhejiang University of Technology Hangzhou 310023

For a series of incoherent condensate atomic clouds with vortices （an orbital angular momentum） released from an optical lattice, the density-density correlation function of this freely expanding ultracold gases is theoretically investigated. It is shown that the nonzero angular momentum of the atoms has an important effect on the fringe pattern of density-density correlation. Particularly, for a short expansion time, even the rotation direction of the atoms could have an observable effect on the fringe pattern. Observation of this specific fringe pattern would constitute experimental evidence for the presence of a vortex in an atomic condensate.

关键词： Quantum gases, liquids and solids Optics, quantum optics and lasers Statistical physics and nonlinear systems

Adrenomedullin: an important participant in neurological diseases

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Neural Regeneration Research 2020年第7期15卷 1199-1207页

作者： Feng-Jiao Li Si-Ru Zheng dong-mei Wang College of Life Sciences Laboratory of Neuroendocrinology Provincial Key Laboratory of Developmental Biology and Neuroscience Fujian Normal University

Adrenomedullin,a peptide with multiple physiological functions in nervous system injury and disease,has aroused the interest of *** review summarizes the role of adrenomedullin in neuropathological disorders,including pathological pain,brain injury and nerve regeneration,and their *** a newly characterized pronociceptive mediator,adrenomedullin has been shown to act as an upstream factor in the transmission of noxious information for various types of pathological pain including acute and chronic inflammatory pain,cancer pain,neuropathic pain induced by spinal nerve injury and diabetic *** of glia-neuron signaling networks in the peripheral and central nervous system by adrenomedullin is involved in the formation and maintenance of morphine *** has been shown to exert a facilitated or neuroprotective effect against brain injury including hemorrhagic or ischemic stroke and traumatic brain ***,adrenomedullin can serve as a regulator to promote nerve regeneration in pathological ***,adrenomedullin is an important participant in nervous system diseases.

关键词： adrenomedullin brain injury glia mechanism morphine tolerance neural regeneration neuroprotective effect pathological pain regeneration sensitization target

Interaction of Cd and citric acid, EDTA in red soil

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Journal of Environmental Sciences 2001年第2期13卷 153-156页

作者： ZHOU dong mei WANG Shen-qiang CHEN Huai man Laboratory of Material Cycling in Pedosphere Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Adsorption and desorption process of cadmium in red soil (Ferrisols) as well as the influence by media' s pH were investigated in detail with and without citric acid and EDTA. Experimental results clearly showed that Cd adsorption in red soil was affected significantly by the coexisted organic chemicals. In the presence of citric acid and EDTA, Cd adsorption in red soil increased with pH in acid media but decreased in high pH one. Further studies placed stress on the adsorbed Cd in red soil which was found to be existed mainly as exchangeable one at pH < 5.5, and desorption rate by 0.10 mol/L NaNO3 gave a peak-shaped curve due to the difference of specifically and nonspecifically adsorbed Cd with pH's change.

关键词： cadmium interaction organic acid red soil

Recent progress in the deactivation mechanism of zeolite catalysts in methanol to olefins

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Science China Chemistry 2024年第12期67卷 3934-3943页

作者： Sheng Fan Han Wang Sen Wang mei dong Weibin Fan State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China University of Chinese Academy of Sciences Beijing 100049China

Methanol to olefins(MTO)as an important reaction in C1 chemistry can effectively transform non-petroleum carbon resources into value-added *** have been widely used as MTO ***,they usually suffer from a rapid deactivation due to bulky coke species production,and thus require continuous regenerations in industrial *** key to design and develop highly stable zeolite catalysts for MTO process is to unravel the deactivation mechanism and clarify the structure–performance relationship of ***,in this mini-review,we investigate the critical intermediate species inducing zeolite deactivation and analyze the formation and evolution pathways of polycyclic aromatic hydrocarbons(PAHs)that are the precursors of carbonaceous *** addition,some methods to alleviate the coking mainly including acid regulation,morphology modification and process optimization,are also summarized.

关键词： methanol to olefins zeolites deactivation mechanism polycyclic aromatic hydrocarbons

Thermodynamic analysis of ethanol synthesis from hydration of ethylene coupled with a sequential reaction

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Frontiers of Chemical Science and Engineering 2020年第5期14卷 847-856页

作者： Jie Gao Zhikai Li mei dong Weibin Fan Jianguo Wang State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China University of the Chinese Academy of Sciences Beijing 100049China

Coal-based ethanol production by hydration of ethylene is limited by the low equilibrium ethylene conversion at elevated *** improve ethylene conversion,coupling hydration of ethylene with a potential ethanol consumption reaction was analyzed *** reactions have been attempted and compared:(1)dehydration of ethanol to ethyl ether(2C2H2OH5■C2H5OC2H5+H2O),(2)dehydrogenation of ethanol to acetaldehyde(C2H2OH5■CH3CHO+H2),(3)esterifica-tion of acetic acid with ethanol(C2H3OH+CH,COOH■CH3COOC2H5+H2O),(4)dehydrogenation of etha-nol to ethyl acetate(2C2H5OH■CH3COOC2H5+2H2),and(5)oxidative dehydrogenation of ethanol to ethyl acetate(2C2H2OH+O2■CH3COOC2H5+2H2O).The equilibrium constants and equilibrium distributions of the coupled reactions were calculated and the effects of feed composition,temperature and pressure upon the ethylene equilibrium conversion were *** results show that dehydrogenation of ethanol to acetaldehyde has lttle effect on ethylene conversion,whereas for dehydrogenation of ethanol to acetaldehyde and ethyl acetate,ethylene conversion can be improved from 8%to 12.8%and 18.5%,respectively,under conditions of H2O/C2H4=2,10 atm and 300℃.The esterification of acetic acid with ethanol can greatly enhance the ethylene conversion to 22.5%;in particular,ethylene can be actually completely converted to ethyl acetate by coupling oxidative dehydrogenation of ethanol.

关键词： ethylene ethanol thermodynamics coupling

Control of aluminum distribution in ZSM-5 zeolite for enhancement of its catalytic performance for propane aromatization

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Frontiers of Chemical Science and Engineering 2024年第8期18卷 15-24页

作者： Zhao Ma Dezhi Shi Sen Wang mei dong Weibin Fan State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China University of Chinese Academy of Sciences Beijing 100049China

Regulation of aluminum distribution in zeolite framework is an effective method for improving its catalytic performance for propane ***,we found that recrystallization and post-realuminization of ZSM-5 cannot only create hollow structures to enhance the diffusion ability,but also adjust the content and position of paired aluminum species in its *** characterizations results confirmed that increase of paired aluminum content and inducement of more aluminum atoms sited in the intersection cavity are beneficial to the formation of aromatic products in propane *** a result,the hollow-structured ZSM-5 zeolite with more paired aluminum(H-200-hollow)showed higher propane conversion and aromatics selectivity than other samples at the same *** catalytic performance of H-200-hollow can be further improved by ion-exchanging with a small amount of Ga(III)*** propane conversion and aromatics selectivity of Ga-200-hollow reached as high as 95%and 70%,respectively,at 540℃ and 1 atm.

关键词： propane aromatization zeolite aluminum distribution recrystallization and post-realuminization

Leaching of Copper and Zinc in a Garden Soil Receiving Poultry and Livestock Manures from Intensive Farming

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Pedosphere 2008年第1期18卷 69-76页

作者： HAO Xiu-Zhen ZHOU dong-mei CHEN Huai-Man dong Yuan-Hua State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 (China) Graduate School of the Chinese Academy of Sciences Beijing 100049 (China)

The leaching characteristics of a garden soil may be greatly affected by application of poultry and livestock manures from intensive farming. Packed soil columns of a garden soil （CK） and the soils after respectively receiving 2% pig manure （PM）, chicken manure （CM）, and commercial organic manure （OM） were leached with 0.05 mol L^-1 Ca（NO3）2 and 0.01 mol L 1 EDTA solutions. The leachate EC （electric conductivity） values gradually increased at the beginning and then reached a stable value when the soil columns were leached with 0.05 mol L^-1 Ca（NO3）2 solution. The leachate EC values showed a peak-shape when leached with 0.01 mol L^-1 EDTA solution. In all the soil columns, the pH values of the leachates decreased with increase of displacement volumes when the Ca（NO3）2 solution was used. The total amounts of Cu and Zn eluted from the four soil columns were significantly correlated with the extracted soil Cu and Zn concentrations by 1.0 mol L^-1 NH4NO3, but were not correlated with the leachate dissolved organic carbon （DOC） contents. The Zn concentration in the leachate of the PM-treated soil column with 0.05 mol L^-1 Ca（NO3）2 solution was above the Quality Standard III for Ground Water of China （GB/T 14848-93, Zn 〈 1.0 mg L^-1）. When compared with 0.05 mol L^-1 Ca（NO3）2, the EDTA solution significantly accelerated Cu and Zn elutions in the manure-treated columns. This suggested that applying poultry and livestock manures from intensive farming to farmland might pose a threat to the groundwater quality.

关键词： copper garden soil leaching manures zinc