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composition characterization and transformation mechanism of dissolved organic phosphorus in wastewater treatment using 31P NMR spectroscopy

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Frontiers of Environmental Science & Engineering 2024年第3期18卷 103-113页

作者： Yuting Zhang Wei Shang SoonThiam Khu Xingcan Zheng Yongli Sun Pengfeng Li Miao Gu Wen-an Zhang Huanmei Ma National Engineering Research Center For Urban Water&Wastewater North China Municipal Engineering Design&Research Institute Co.Ltd.Tianjin 300381China School of Environment Science&Engineering Tianjin UniversityTianjin 300350China

The migration and transformation of phosphorus components in wastewater treatment plants(WWTPs)play a crucial role in the convergence and circulation of ***,the composition and variation of dissolved organic phosphorus(DOP)in WWTPs were unclear because of its complex nature,hindering its efficient *** this study,the DOP species and their transformation during the treatment process in WWTP were comprehensively ***,two enrichment methods were assessed for their effectiveness at facilitating wastewater analysis:lyophilization and aluminum salt *** salt precipitation was found to be better because its application allowed 31P nuclear magnetic resonance(31P NMR)spectroscopy to identify more species in the secondary effluent:orthophosphate(Ortho-P)(81.1%–89.3%of the dissolved total phosphorus),pyrophosphates(Pyro-P)(0%–2.3%),orthophosphate monoesters(Mono-P)(7.0%–10.77%),orthophosphate diesters(Di-P)(1.0%–2.96%),and phosphonate(Phos-P)(1.7%–5.16%).Furthermore,the variation and transformation mechanism of phosphorus,particularly those of DOP,during the entire sewage-treatment process were *** the treatment steps,biological treatment combined tertiary treatment achieved better DOP removal ***,biological treatment mainly removed Mono-P and Di-P with removal efficiencies of 33.3%and 41.7%compared with the effluent of the grit ***-P has higher bioavailability and is more easily converted and utilized by microorganisms than ***,Phos-P,with low bioavailability,was hardly utilized by microorganisms,which showed only 18.4%removal efficiency in biological *** tertiary treatment,coagulation process exhibited higher removal ability of Ortho-P(69.1%)and partial removal efficiencies of DOP,resulting in an increase in the DOP proportion in *** addition,Phos-P could not be effectively removed through the biological treatment and was only partially reduced via the adsorption pro

关键词： Municipal wastewater Dissolved organic phosphorus composition Transformation 31P nuclear magnetic resonance

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A detailed comparison of the composition of(RE)-Ba-Cu-O-Ag bulk superconductors

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Superconductivity 2024年第1期9卷 87-94页

作者： J.V.J.Congreve Y.Shi A.R.Dennis H.Druiff N.C.Tutt D.A.Cardwell J.H.Durrell Department of Engineering University of CambridgeCambridgeUK

The homogeneity of the microstructure and composition are critical in determining the properties of rare earthbarium‐cuprate,single grain bulk superconductors[(RE)BCO].The magnitude of the trapped magnetic field achieveable in these technologically important materials,in particular,is influenced heavily by the size and distribution of(RE)_(2)BaCuO_(x)(RE‐211)flux pinning inclusions in the bulk microstructure,whereas the size and distribution of silver agglomerates present within the bulk superconducting matrix correlate directly with improved mechanical *** careful engineering,these materials have significant potential for application in range of devices related to energy storage,medicine,electro‐magnetic machinery and microelectronic *** of(RE)BCO bulk superconductors typically involves heating a powder compact above its peritectic decomposition temperature followed by slow cooling to facilitate the growth of a single ***(RE)BCO composition has a different peritectic temperature and growth rate,which,therefore,necessitates different requirements in the heating *** fabrication temperature and growth rate,for example,may have an effect on the RE‐211 and silver distribution,which may,in turn,affect the superconducting properties of the resulting single *** this work we compare the distributions of silver and RE‐211 in the single grain microstructures of YBCOAg,GdBCO‐Ag,EuBCO‐Ag and SmBCO‐Ag bulk superconductors using optical microscopy,scanning electron microscopy and energy dispersive X‐ray *** observe that the distributions are very similar along both the a/b‐axis and c‐axis of these *** suggests that factors other than the maximum temperature used to achieve peritectic decomposition and the rate of single grain growth are particularly influential in determining the properties of the as‐processed samples in the top seeded melt growth *** observation demonstrates there is freedom to us

关键词： YBCO‐Ag GdBCO‐Ag SmBCO‐Ag EuBCO‐Ag composition Bulk superconductor

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composition and Structure of Ti-6Al-4V Alloy Plasma-based Ion Implanted with Nitrogen

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Rare Metals 2000年第3期19卷 197-203页

作者：季红兵夏立方马欣新孙跃孙明仁张振信张华芳哈尔滨工业大学黑龙江哈尔滨 150001 哈尔滨理工大学黑龙江哈尔滨 150080

The composition and structure of Ti 6Al 4V alloy plasma based ion implanted with nitrogen was *** nitrogen depth distribution shows more antiballistic with distribution peak heightened with increased implantation time(dose),and more like a parabola at the low implantation pulse *** implantation pulse voltage is increased,the implantation depth increased with the nitrogen distribution peak being deepened,widened and lowered ***,TiN+Ti 2N,or Ti 2N second phases were formed in the implanted *** relative percentage of nitrogen content in the form of TiN increases when going deeper into the implanted(TiN formed) *** increase of implantation pulse width and/or time is favourable for the formation of TiN rather than Ti *** is unfavourable for formation of any nitrides when implantation pulse voltage is decreased to 30kV or *** crystalline particles (made mainly of Ti 2N and a smaller percentage of TiO 2 phases) of regular shapes such as triangle and tetragon, etc .(about 20 nm) are found distrbuted dispersively in the near surface region of samples implanted at the high implantation pulse voltage (75kV).

关键词： composition Structure Ti 6Al 4V alloy Plasma based ion implantation

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composition-tuned oxidation levels of Pt-Re bimetallic nanoparticles for the etherification of allylic alcohols

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Nano Research 2018年第11期11卷 5902-5912页

作者： Yuhao Wang Lindong Li Ke Wu Rui Si Lingdong Sun Chunhua Yan Beijing National Laboratory for Molecular Sciences State Key Laboratory of Rare Earth Materials Chemistry and Applications PKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic Chemistry College of Chemistry and Molecular Engineering Peking University Beijing 100871 China Shanghai Synchrotron Radiation Facility Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201204 China

The catalytic performance of metal nanoparticles is often affected by surface oxidation levels. Instead of post-synthesis oxidation/reduction, we propose an efficient method to modulate the oxidation levels by tuning the composition of bimetallic nanoparticles. Here we report a series of Pt–Re bimetallic nanoparticles synthesized via a facile thermal co-reduction process, with a uniform size of approximately 3 nm. The investigation of the growth of the Pt–Re nanoparticles suggests that the Re atoms were enriched on the surface, as confirmed by X-ray photoelectron spectroscopy. Furthermore, X-ray absorption spectroscopy showed that metallic Re was decreased and high-valency ReOx species were increased in particles with higher Re/Pt ratios. In the etherification of allylic alcohols catalyzed by Pt–Re nanoparticles of different compositions under ambient conditions, particles with higher Re/Pt ratios exhibited significantly better performances. The highest mass activity of Pt–Re bimetallic nanoparticles (127 μmol·g−1·s−1) was more than forty times that of the industrial catalyst CH3ReO3 (3 μmol·g−1·s−1). The catalytically active sites were associated with ReOx and could be tuned by adjusting the Pt ratio.

关键词： nanocatalysis Re Pt oxidation level composition allylic alcohol

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composition demixing effect on cathodic arc ion plating

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Journal of University of Science and Technology Beijing 2006年第2期13卷 125-130页

作者： Jun Zhang Li Li Lipeng Zhang Shilu Zhao Qiang Guo Department of Materials Science and Engineering. Shenyang University Shenyang 110044 China State Key Laboratory of Materials Modification by Laser Ion and Electron Beams Dalian 116024 China

The composition demixing effect has been found often in alloy coatings deposited by cathodic arc ion plating using various alloy cathode targets. The characteristics of composition demixing phenomena were summarized. Beginning with the ionization zone near the surface of the cathode target, a physical model in terms of the ions generated in the ionization zone and their movement in the plating room modified by bias electric field was proposed. Based on the concept of electric charge state, the simulation calculation of the composition demixing effect was carried out. The percentage of atoms of an element in coating and from the alloy target was demonstrated by direct comparison. The influences of the composition change of the alloy target and the bias electric field on the composition demixing effect were discussed in detail. It is also proposed that the average charge states of the elements may be used to calculate the composition demixing effect and to design the composition of the alloy target.

关键词： cathodic arc ion plating alloy coating composition demixing

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composition evolution and deformation of different non-metallic inclusions in a bearing steel during hot rolling

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Journal of Iron and Steel Research International 2022年第4期29卷 552-562页

作者： Nan Liu Gong Cheng Li-feng Zhang Wen Yang Ying Ren Guo-cheng Wang Xiao-ming Liu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Steelmaking Plant Baotou Steel Union Co.Ltd.Baotou 014010Inner MongoliaChina Engineering Technology Co. Ltd.WISDRI Engineering and Research Incorporation LimitedWuhan 430223HubeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina

The composition evolution and deformation of different non-metallic inclusions in a bearing steel during hot rolling were investigated by the automatic detection and the improved non-aqueous electrolysis *** sulfide,MnS–TiN,and liquid CaO–Al_(2)O_(3) inclusions were elongated while TiN and MgO-Al_(2)O_(3) were fractured during hot *** CaS–MnS phase in the MgO–Al_(2)O_(3)–CaS–MnS inclusion was separated from the inclusion,leading to the formation of CaS–MnS type ***,the CaS and MnS contents in oxide-containing inclusions decreased while the MgO and Al_(2)O_(3) contents increased after hot *** deformability of different inclusions in the bearing steel was quantitatively compared and discussed.

关键词： Bearing steel Hot rolling composition evolution Deformability Inclusion

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composition influence on the microstructures and magnetic properties of FePt thin films

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Chinese Physics B 2013年第4期22卷 452-454页

作者：刘立旺党红刚盛伟王颖曹江伟白建民魏福林 Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education Lanzhou University

The Fex Pt 100x （10nm）（x=31–51） thin films are fabricated on Si （100） substrates by using magnetron sputtering. The highly ordered L1 0 FePt phase is obtained after post-annealing at 700℃in Fe 47 Pt 53 thin film. The sample shows good perpendicular anisotropy with a square loop and a linear loop in the out-of-plane and the in-plane direction, respectively. The variations of the magnetic domains are investigated in the films when the content value of Fe changes from 31% to 51%.

关键词： FePt coercivity composition magnetic domain

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composition and Morphology of Electrodeposited CuInSe_2 Precursor Films

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Journal of Materials Science & Technology 2009年第2期25卷 242-246页

作者： Fangyang Liu Zhian Zhang Yanqing Lai Jie Li Yexiang Liu School of Metallurgical Science and Engineering Central South University Changsha 410083 China

CulnSe2 （CIS）precursor films have been prepared by electrodeposition in aqueous solution. The electrodeposited films were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and energy dispersive X-ray spectroscopy （EDS） for structural, morphological and componential properties. The influence of deposition potential and Na-citrate concentration on composition and morphology of electrodeposited films was studied in detail. It is found that the film morphology is strongly influenced by deposition potential and Na-citrate concentration. Films with large and homogenous grain size and ratio of Cu/In approaching 1 were obtained at deposition potentials of -0.7 and -0.75 V vs the saturated calomel electrode （SCE） and Na-citrate concentration of 500 mmol/L. Chalcopyrite phase CulnSe2 is contained in precursor films that have poor crystallinity.

关键词： CuInSe2 Electradeposition composition Morphology

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composition analysis and antioxidant activities of the Rhus typhina ***

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Journal of Pharmaceutical Analysis 2019年第5期9卷 332-338页

作者： Ting Liu Zhaoqin Li Ruiyun Li Yue Cui Yunli Zhao Zhiguo Yu School of Pharmacy Shenyang Pharmaceutical University 103 Wenhua Road Shenhe District Shenyang 110016 China The Precise Medicine Center Key Laboratory of Environmental Pollution and Microecology Liaoning ProvinceCollege of Basic Medical Sciences Shenyang Medical College No. 146 North Huanghe Street Huanggu District Shenyang 110034 China

The present investigation reports the chemical composition of the Rhus typhina L. stem identified via mass spectrometry and NMR as gallic acid, 1-O-galloyl-β-D-glucose, tryptophan, scopolin, methyl gallate, fustin, quercetin, rutin, and 1,2,3,4,6-penta-O-galloyl-β-D-glucose. The antioxidant properties and the chemical composition contents of the R. typhina L. stem grown in different regions in China were determined. To determine the antioxidant activity, a total phenolic content analysis, 2, 2-diphenyl-1-picrylhydrazyl radical scavenging activity assay, ferric reducing antioxidant power assay, and β-carotene linoleic acid model system were conducted. The results showed that the Rhus typhina L. stem possessed high antioxidant capacities due to its high phenolic content. The contents of the nine isolated compounds were determined by UPLC-ESI-MS/MS. The calibration curves of the nine isolated compounds were linear within the concentration range and the average recoveries were high. The result showed that 1-Ogalloyl-β-D-glucose, gallic acid, methyl gallate, and 1,2,3,4,6-penta-O-galloyl-β-D-glucose could be the compounds mainly responsible for the antioxidant capacity of the R. typhina L. stem. This reveals that the R. typhina L. stem is a good source of antioxidants.

关键词： Rhus typhina L. stem Antioxidant activity Chemical composition UPLC-ESI-MS/MS

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composition operators on the Lipschitz space in polydiscs

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Science China Mathematics 2003年第1期46卷 33-38页

作者：周泽华 Department of Mathematics Tianjin University

Let Un be the unit polydisc of Cn and φ = (φ 1,...,φ n ) a holomorphic self-map of Un. Let 0 ≤α 1. This paper shows that the composition operator C is bounded on the Lipschitz space Lip(Un) if and only if there exists M > 0 such that $$\sum\limits_{k,l = 1}^n {\left| {\frac{{\partial \phi _l }}{{\partial zk}}(z)} \right|\left( {\frac{{1 - \left| {z_k } \right|^2 }}{{1 - \left| {\phi _l (z)} \right|^2 }}} \right)^{1 - \alpha } } \leqslant M$$ for z ∈ Un. Moreover Cφ is compact on Lipα(Un) if and only if Cφ is bounded on Lipα(Un) and for every ε>0, there exists a δ > 0 such that $$\sum\limits_{k,l = 1}^n {\left| {\frac{{\partial \phi _l }}{{\partial zk}}(z)} \right|\left( {\frac{{1 - \left| {z_k } \right|^2 }}{{1 - \left| {\phi _l (z)} \right|^2 }}} \right)^{1 - \alpha } } \leqslant \varepsilon $$ whenever dist((z),?Un).

关键词： Lipschitz space, polydisc, composition operator.

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