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Chelation of heavy metals by potassium butyl dithiophosphate

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Journal of Environmental Sciences 2011年第5期23卷 778-783页

作者： Ying Xu Zhigang Xie lu xue Key Laboratory of Integrated Regulation and Resource Development of Shallow Lakes of Ministry of Education Hohai University Nanjing 210098 China. E-mail: xyhohai@ *** College of Environmental Science and Engineering Hohai University Nanjing 210098 China

Potassium butyl dithiophosphate （PBD） was developed and introduced as a new chelating agent for heavy metal removal. The synthesized PBD were characterized by IR and NMR. The effects of pH, chelating agent dosage, and other heavy metal ions on the performance of PBD in Cd^2＋ removal from water are investigated. Experimental results showed that the chelating agent could be used to treat acidic heavy metal wastewater. The Cd^2＋ removal was not affected by solution pH value within the range of 2 to 6. The Cd^2＋ removal rate could reach over 99%. Therefore, the deficiency of the precipitation process using hydroxide under alkaline condition can be overcome. Without the need for pH adjustment, the method could save on costs. If Cd^2＋ co-exists with Pb^2＋ and Cu^2＋, the affinity of the chelating agent with these three heavy metal ions was in the order of： Cu^2＋〉 Pb^2＋〉 Cd^2＋. Through PBD chelating precipitation, all the contents of Pb^2＋, Cd^2＋, and Cu^2＋ in wastewater met the standard levels through a one-step treatment. The one-step treatment process was superior to the process （sectional treatment is required） of precipitation with hydroxide. When the pH was between 3 and 11, the amount of leached chelated Cd^2＋ was much lower than that obtained by precipitation with hydroxide. Therefore, the risk of environmental pollution could be further reduced.

关键词： chelation heavy metal precipitation stability wastewater

"Solid-Liquid" Vitrimers Based on Dynamic Boronic Ester Networks

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Chinese Journal of Polymer Science 2021年第10期39卷 1292-1298,I0006页

作者： Sheng Wang lu-lu xue Xiao-Zhuang Zhou Jia-Xi Cui INM-Leibniz Institute for New Materials Campus D22 Saarbrucken 66123Germany Beijing National Laboratory for Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China

The"solid-liquid"behavior of vitrimers have not been systematically ***,a series of"solid-liquid"vitrimers bearing varying contents of dynamic boronic ester bonds were synthesized via thiol-ene click *** vitrimers allow for flexibile modulation of their network structures and thus show a range of intriguing properties including high stretchability,flexible transition from elasticity to plasticity,strong strain rate dependence,and solid-liquid *** dynamic association rate of boronic ester bonds within these vitrimers could be apparently accelerated via increasing the content of boronic ester,which could be used to shape-program the flat vitrimer films into various complex 3D structures just with external *** with such versatile dynamic behavior may open up a range of new applications.

关键词： Solid-liquid Dynamic covalent bond Boronic ester bond Strain-rate dependent High stretchability

Wideband Circularly Polarized Substrate-Integrated Waveguide Aperture-Coupled Metasurface Antenna Array for Millimeter-Wave Applications

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Chinese Journal of Electronics 2024年第6期33卷 1468-1477页

作者： Jiwei LIAN Chun GENG xue lu Dazhi DING School of Microelectronics(School of Integrated Circuits) Nanjing University of Science and Technology State Key Laboratory of Millimeter Waves Southeast University Qian xuesen College Nanjing University of Science and Technology

A wideband circularly polarized(CP) aperture-coupled metasurface antenna operating at millimeterwave frequency spectrum in substrate-integrated waveguide(SIW) technology is proposed. The proposed metasurface antenna is composed of two substrates. The first substrate contains an end-shorted SIW section with a slot *** introduced metasurface is printed on the top of the second substrate. The metasurface is comprised of 3 × 3 unit cells, each of which contains two interconnected patches and two parasitic patches. The working mechanism of the proposed metasurface antenna is illustrated in details. The proposed metasurface antenna has wide impedance bandwidth and axial ratio(AR) bandwidth, which are 66.7% and 40%, respectively. Using the proposed metasurface antenna, a 4 × 4 CP metasurface antenna array with an impedance bandwidth of 24%, an AR bandwidth of 30%, and a peak gain of 18.7 dBic in simulation is developed in this paper for millimeter-wave applications.

关键词： Antenna measurements Parametric study Millimeter wave technology Metasurfaces Aperture antennas Impedance Broadband antennas Substrates Wideband Antenna arrays

Superoxide Dismutase Plays an Important Role in Maize Resistance to Soil CO_(2)Stress

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Acta Geologica Sinica(English Edition) 2023年第3期97卷 995-1001页

作者： xue lu MA Junjie HU Qian MA Jinfeng Carbon Neutral College(Yulin) Northwest UniversityXi’an 710069China College of Life Science Yulin UniversityYulinShaanxi 719000China National&Local Joint Engineering Research Center of Carbon Capture and Storage Technology Northwest UniversityXi’an 710127China Shaanxi Key Laboratory for Carbon Neutral Technology Northwest UniversityXi’an 710069China Department of Geology Northwest UniversityXi’an 710069China College of Urban and Environmental Sciences Northwest UniversityXi’an 710127China Oil Production Plant No.1 Sinopec North China Oil&Gas CompanyXianyangShaanxi 712000China

CO_(2)capture and storage(CCS)has the risk of CO_(2)leakage,and this leakage always increases soil CO_(2)concentration,and the long-term CO_(2)stress damages crop production in *** maize,the growth characteristics,such as plant height and yield,and physiological indexes(osmoregulation substances and antioxidant enzymes)were explored under different simulative CO_(2)leakage ***,the relationship between maize physiological indexes and soil CO_(2)concentration was analyzed,showing that soil CO_(2)stress inhibited maize growth to a certain extent,resulting in shorter plants,thinner stems and lower kernel *** an increase in soil CO_(2)concentration,the contents of malondialdehyde,soluble sugar and soluble protein in maize leaves increased;with continuing stress,the increase rate of malondialdehyde was greatly augmented,whereas the increase rates of soluble sugar and soluble protein *** extended CO_(2)stress,the activity of the enzyme superoxide dismutase(SOD)increased continuously,while the activities of catalase and peroxidase first increased and then *** dismutase activity was closely correlated with soil CO_(2)concentration(r=0.762),and responded quickly to the change of soil CO_(2)concentration(R~2=0.9951).Therefore,SOD plays an important role in maize resistance to soil CO_(2)*** study will help further understanding of the mechanism of maize tolerance to soil CO_(2)stress,providing a theoretical basis for agricultural production in CCS project areas.

关键词： CO_(2)capture and storage CO_(2)leakage soil CO_(2)stress antioxidant enzyme system maize

TG-FTIR Study on Corn Straw Pyrolysis-influence of Minerals

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Chemical Research in Chinese Universities 2006年第4期22卷 524-532页

作者： YANG Chang-yan lu xue-song LIN Wei-gang YANG xue-ming YAO Jian-zhong Multiphase Reaction Lab Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 P. R. China Graduate School of the Chinese Academy of Sciences Beijing 100039 P. R. China

In order to study the effect of minerals on biomass pyrolysis, experiments on pyrolysis of corn straw with different pretreatment methods were performed by using a thermogravimetric analyzer（TGA） coupled with a Fourier transform infrared （FTIR） spectrometer. The pretreatment methods included water washing and acid washing. The experimental results show that acid washing can remove almost all K^＋ and 78% of Ca^2＋ , while water washing only removes most of K ^＋. The existence of K^＋ and Ca^2＋ obviously favors the formation of compounds containing carbonyl groups and CO2 , but it will decrease the yields of compounds containing C-O-C groups. However, the formation of H2O, CO and CH4 are slightly affected by the removal of inorganic ions. With regard to the structure of the metal ions-adsorbed cellulose characterized by IR analysis, it can be considered that there is an ＂ion force＂ between metal ions and cellulosic biomass. The results of thermal kinetic analysis show that this force can make the reaction activation energy of the biomass pyrolysis decrease. A new mechanism is proposed for explaining the effect of inorganic ions on cellulose pyrolysis.

关键词： Biomass TG-FTIR Pretreatment Minerals Pyrolysis mechanism

Parametrized Area Integrals on Hardy Spaces and Weak Hardy Spaces

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Acta Mathematica Sinica,English Series 2007年第9期23卷 1537-1552页

作者： Yong DING Shan Zhen lu Qing Ying xue School of Mathematical Science Beijing Normal University Beijing 100875 P. R. China

In this paper, the authors prove that if Ω satisfies a class of the integral Dini condition, then the parametrized area integral μΩ,S^ρ is a bounded operator from the Hardy space H1 （R^n） to L1 （R^n） and from the weak Hardy space H^1,∞ （R^n） to L^1,∞ （R^n）, respectively. As corollaries of the above results, it is shown that μΩ,S^ρ is also an operator of weak type These conclusions are substantial improvement and （1, 1） and of type （p,p） for 1 〈 p 〈 2, respectively extension of some known results.

关键词： area integral Hardy space weak Hardy space integral Dini condition

Recent Developments of Dinitrogen Activation on Metal Complexes and Clusters

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Chinese Journal of Structural Chemistry 2022年第12期41卷 80-88页

作者： xue-lu Ma Meng Li Jun-Bo lu Cong-Qiao Xu Jun Li School of Chemical&Environmental Engineering China University of Mining&TechnologyBeijing 100083China Department of Chemistry Southern University of Science and TechnologyShenzhen 518055China Department of Chemistry and Key Laboratory of Organic Optoelectronics&Molecular Engineering of Ministry of Education Tsinghua UniversityBeijing 100084China

Dinitrogen(N_(2)) is the major component of the atmosphere and many factors bring about dinitrogen inertness with low reactivity. Dinitrogen activation on metal complexes and clusters under ambient condition is the long-standing goal in the modern chemistry. In this review,an attempt has been made to survey the mechanistic aspects of dinitrogen activation and functionalization based on different coordination binding modes of dinitrogen. Our goal is to provide a comprehensive survey of dinitrogen activation in order to guide the relevant research in the future.

关键词： dinitrogen activation binding mode dinitrogen complex metal cluster synergistic mechanism

Hybrid partial least squares and neural network approach for short-term electrical load forecasting

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控制理论与应用（英文版） 2008年第1期6卷 93-96页

作者： Shukang YANG Ming lu Huifeng xue College of Automation Northwestern Polytechnical University Xi＇an Shanxi 710072 China

Intelligent systems and methods such as the neural network （NN） are usually used in electric power systems for short-term electrical load forecasting. However, a vast amount of electrical load data is often redundant, and linearly or nonlinearly correlated with each other. Highly correlated input data can result in erroneous prediction results given out by an NN model. Besides this, the determination of the topological structure of an NN model has always been a problem for designers. This paper presents a new artificial intelligence hybrid procedure for next day electric load forecasting based on partial least squares （PLS） and NN. PLS is used for the compression of data input space, and helps to determine the structure of the NN model. The hybrid PLS-NN model can be used to predict hourly electric load on weekdays and weekends. The advantage of this methodology is that the hybrid model can provide faster convergence and more precise prediction results in comparison with abductive networks algorithm. Extensive testing on the electrical load data of the Puget power utility in the USA confirms the validity of the proposed approach.

关键词： Electric loads Forecasting Hybrid neural networks model

Disseminated strongyloidiasis in a patient with rheumatoid arthritis:A case report

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World Journal of Clinical Cases 2022年第18期10卷 6163-6167页

作者： Jin-Hao Zheng lu-Yu xue Department of Critical Care Medicine Huashan Hospital Affiliated to Fudan UniversityShanghai 200040China

BACKGROUND Strongyloidiasis is usually a chronic infection but it can develop into a fatal disease in immunosuppressed *** SUMMARY A 68-year-old male with rheumatoid arthritis was treated with a variety of immunosuppressants for the past 3 ***,the patient presented with a partial small-bowel obstruction,petechia,coughing and peripheral *** diagnosis was difficult to clarify in other *** hospital found Strongyloides stercoralis larvae with active movement in the routine stool and sputum *** diagnosis of disseminated strongyloidiasis was *** combined with albendazole was used for *** patient responded to therapy and was *** This case underscores the importance of comprehensive differential diagnosis in immunocompromised patients.

关键词： Strongyloidiasis Rheumatoid arthritis Immunosuppressants Small-bowel obstruction Ivermectin Albendazole Case report