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Density-Functional Theories for Polyelectrolyte Systems

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Chinese Journal of Polymer Science 2024年第9期42卷 1302-1312,I0006页

作者： Jia-Wei Zhang Yu-Hang Zhang Bao-Hui Li Qiang Wang School of Physics Nankai UniversityTianjin90001China Department of Chemical and Biological Engineering Colorado State University1370 Campus DeliveryFort CollinsCO80523-1370USA

Polymer density-functional theories(PDFTs)have distinct advantages in the study of polyelectrolyte(PE)systems over experiments and molecular *** we give an introductory review of some PDFTs recently developed for PE *** start with a general formalism of PDFTs and its relation to the widely used polymer self-consistent field theory(SCFT),then explain the various correlations that are neglected in SCFT but can be accounted for in PDFTs,including those due to the excluded-volume interaction and chain connectivity of uncharged polymers,the electrostatic correlations of small ions,and the chain correlations in *** also list some applications of PDFTs for PE systems,and finally give some perspectives on future *** hope that our review can attract more researchers to apply and further develop PDFTs as a promising class of theoretical and computational tools.

关键词： Polymer density-functional theories Polyelectrolytes correlations

Fabricating functionally graded Fe-Cr-co permanent magnetic alloys via laser powder bed fusion

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Journal of Iron and Steel Research(International) 2024年第3期31卷 729-737页

作者： Ya-zhou He Ya-qing Hou Peng Shen Hao Zhang Dong Zhou Hang Su Central Iron and Steel Research Institute co. Ltd.Beijing 100081China Material Digital R&D Center China Iron and Steel Research Institute Group Co.Ltd.Beijing 100081China

Laser powder bed fusion(LPBF)in-situ alloying technology offers the possibility to construct gradient materials with varied structures and *** graded Fe-Cr-co permanent magnetic alloys were fabricated by LPBF and in-situ alloying mixed powders of Fe,Cr,and co *** effects of different Fe,Cr and co contents on the microstructure,magnetic properties and hardness of Fe-Cr-co alloys prepared by LPBF were *** as-built Fe-Cr-co alloys present a single body-centered-cubic phase and have a homogeneous distribution of *** mechanical properties and magnetic properties of the compositionally graded sample show a gradient *** the increase in Cr content,the Vickers hardness of the sample increases,and the saturation magnetization of the sample *** optimal magnetic properties in an isotropic state are given as coercivity HcB=21.65 kA/m,remanence Br=0.70 T and energy product(BH)_(max)=5.35 kJ/m^(3),which are comparable to or higher than the reported magnetic properties in an isotropic state prepared by traditional powder *** in-situ alloying technology has the potential to further explore Fe-Cr-co magnetic materials,such as those consisting of multiple or more constituent elements,and to maximize the compositional flexibility of magnetic materials.

关键词： Fe-Cr-co alloy Laser powder bed fusion In-situ alloying Functional material Magnetic property

High-efficiency co_(2) sequestration through direct aqueous carbonation of carbide slag: determination of carbonation reaction and optimization of operation parameters

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Frontiers of Environmental Science & Engineering 2024年第1期18卷 157-167页

作者： Zhiqiang Wang Longpeng Cui Yanfang Liu Jili Hou Hongwei Li Liang Zou Fuxia Zhu Department of coal and Syngas conversion Sinopec Research Institute of Petroleum Processing Co.Ltd.Beijing 100083China

Under the dual-carbon target, co_(2) mineralization through solid wastes presents a mutually beneficial approach for permanent carbon emission reduction at a low material cost, while also enabling the resource utilization of these wastes. However, despite its potential, a comprehensive understanding about the effect of industrial solid waste properties and operating parameters on the carbonation process, and the mechanism of direct aqueous carbonation is still lacking. A series of experiments were conducted to compare the carbonation performance of fly ash, steel slag, and carbide slag. Subsequently, co_(2) mineralization by carbide slag was systematically studied under various operating parameters due to its high co_(2) sequestration capacity. Results showed the reactivity of CaO and Ca(OH)2 was higher than that of CaO·SiO_(2) and 2CaO·SiO_(2). Carbide slag demonstrated a sequestration capacity of 610.8 g co_(2)/kg and carbonation efficiency ζCa of 62.04% under the conditions of 65 ℃, 1.5 MPa initial co_(2) pressure, 15 mL/g liquid-to-solid ratio, and 200 r/min stirring speed. Moreover, the formation of carbonates was confirmed through XRD, SEM-EDS, TG, and FTIR. A mechanism analysis revealed that initially, the rate of the carbonation process was primarily controlled by the mass transfer of co_(2) in the gas–liquid interface. However, the rate-determining step gradually shifted to the mass transfer of Ca2+ in the solid–liquid interface as the reaction time increased. This study lays the foundation for the large-scale implementation of co_(2) sequestration through carbide slag carbonation.

关键词： Industrial by-products Direct aqueous carbonation co_(2)sequestration Mass transfer

Sulfur and carbon co-doped g-C_(3)N_(4)microtubes with enhanced photocatalytic H2 production activity

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Frontiers in Energy 2024年第1期18卷 110-121页

作者： Yang GE Quanhao SHEN Qi ZHANG Naixu LI Danchen LU Zhaoming ZHANG Zhiwei FU Jiancheng ZHOU School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189China Shangdong Yellow Triangle Biotechnology Industry Research Institute co. Ltd.Dongying 257091China Xuzhou B&C Chemical co. Ltd.Xuzhou 221300China

Metal-free graphitic carbon nitride(g-C_(3)N_(4))has captured significant attention as a low-cost and efficient hydrogen production photocatalyst *** regulating the microstructure and accelerating the separation of photogenerated carriers remain crucial strategies for promoting the photocatalytic performance of this ***,a novel sulfur–carbon co-doped g-C_(3)N_(4)(SCCN)hierarchical microtubules filled with abundant nanosheets inside by thermal polymerization is *** nanosheets create abundant pores and cavities inside the SCCN microtubes,thereby increasing the specific surface area of g-C_(3)N_(4)and providing sufficient reactant attachment ***,the hierarchical structure of SCCN microtubules strengthens the reflection and scattering of light,and the utilization of visible light is favorably *** importantly,co-doping S and C has greatly improved the photocatalytic performance of graphitic carbon nitride,optimized the band gap structure and enhanced the photogenerated carrier ***,the SCCN exhibits a remarkable photocatalytic H_(2)evolution rate of 4868μmol/(g·h).This work demonstrates the potential of multi-nonmetal doped g-C_(3)N_(4)as the ideal photocatalyst for H2 evolution.

关键词： carbon nitride photocatalysis hydrogen production

Revealing effect of Al content on oxidation of novel co-Cr-Nb-W carbide-strengthened superalloy

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Rare Metals 2024年第9期43卷 4521-4534页

作者： Chen Ling Shang-Ping Li Jie Hou He-Li Luo Central Iron & Steel Research Institute Beijing GAONA Materials&Technology co. Ltd.

The high-temperature oxidation behavior of novel co-Cr-Nb-W carbide-strengthened wear-resistance alloys with different Al contents（1wt%, 2wt% and 3wt%）at 950, 1000 and 1050 °C was thoroughly investigated by scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and field emission electron probe analyzer. The porous property of Nb C in-situ oxidation products（Nb2O5, co Nb2O6and co4Nb2O9） induces a multi-layered oxide scale with micropores and ***-Cr-Nb-W alloy with 1 wt% Al undergoes catastrophic oxidation and spalling above 1000 °C. The outward transportation of Cr and co is effectively restrained by a continuous Al2O3scale formed around Nb C in-situ oxidation region when Al content reaches 3 wt%. The β-co Al in co-Cr-Nb-W alloy with 3 wt% Al has an oxidation priority over eutectic carbides and the alloy matrix which are both enriched with Cr, thereby preventing the formation of Cr-depletion area and improving the self-healing ability of the oxide film. A slight change in Al content has a remarkable influence on the cooperative effect of Al and Cr and multiplies the antioxidant capacity of co-Cr-Nb-W alloy above 1000 °C.

关键词： High-temperature oxidation behavior Microstructure Oxidation kinetics Superalloy Wear-resistant alloy

The occurrence,inheritance,and segregation of complex genomic structural variation in synthetic Brassica napus

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The Crop Journal 2024年第2期12卷 515-528页

作者： Dandan Hu Jin Lu Wenwen Li Yinghui Yang Junxiong Xu Han Qin Hao Wang Yan Niu Huaiqi Zhang Qingqing Liu Xiangxiang He Annaliese S.Mason JChris Pires Zhiyong Xiong Jun Zou National Key Laboratory of Crop Genetic Improvement College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhan 430070HubeiChina college of Agronomy Henan Agricultural UniversityZhengzhou 450002HenanChina Key Laboratory of Herbage and Endemic Crop Biotechnology Inner Mongolia UniversityHohhot 010070Inner MongoliaChina Plant Breeding Department University of BonnBonn 53115Germany Department of Soil and Crop Sciences Colorado State UniversityFort CollinsCO 80523USA

"Synthetic"allopolyploids recreated by interspecific hybridization play an important role in providing novel genomic variation for crop *** synthetic allopolyploids often undergo rapid genomic structural variation(SV).However,how such SV arises,is inherited and fixed,and how it affects important traits,has rarely been comprehensively and quantitively studied in advanced generation synthetic lines.A better understanding of these processes will aid breeders in knowing how to best utilize synthetic allopolyploids in breeding ***,we analyzed three genetic mapping populations(735 DH lines)derived from crosses between advanced synthetic and conventional Brassica napus(rapeseed)lines,using whole-genome sequencing to determine genome *** observed high tolerance of large structural variants,particularly toward the telomeres,and preferential selection for balanced homoeologous exchanges(duplication/deletion events between the A and C genomes resulting in retention of gene/chromosome dosage between homoeologous chromosome pairs),including stable events involving whole chromosomes("pseudoeuploidy").Given the experimental design(all three populations shared a common parent),we were able to observe that parental SV was regularly inherited,showed genetic hitchhiking effects on segregation,and was one of the major factors inducing adjacent novel and larger ***,novel SV occurred at low frequencies with no significant impacts on observed fertility and yield-related traits in the advanced generation synthetic ***,incorporating genome-wide SV in linkage mapping explained significantly more genetic variance for *** results provide a framework for detecting and understanding the occurrence and inheritance of genomic SV in breeding programs,and support the use of synthetic parents as an important source of novel trait variation.

关键词： Allopolyploid Large Genome structural variation Linkage mapping Synthetic polyploids Inheritance and segregation

Advances in Polymeric Carbon Nitride Photocatalysts for Enhanced co_(2)Reduction

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 1-12页

作者： Liu Bing Sun Shangcong Song Ye Peng Bo Lin Wei SINOPEC Research Institute of Petroleum Processing co. Ltd.Beijing100083China

Photocatalysis has emerged as a promising alternative for converting and utilizing co_(2).Polymeric carbon nitride(PCN),typically synthesized through the one-step thermal polycondensation of nitrogen-rich precursors,has shown considerable promise due to its adjustable band structure and inherent *** the past five years,significant literature in this field has identified five primary methods for modifying PCN:morphology modulation,element doping,defect induction,co-catalyst loading,and heterojunction construction.A detailed discussion on how each modification method influences light absorption,charge separation,and surface reaction efficiencies in photocatalysis is *** on these findings,several future directions for the development of PCN-based materials are proposed,such as designing tailored PCN structures for specific photocatalytic reactions and using theoretical calculations to verify and correct results from current characterization *** the challenges associated with the large-scale synthesis of PCN materials with controllable structures and satisfactory performance,this work offers valuable insights for advancing photocatalytic PCN-based systems for large-scale solar fuel production.

关键词： carbon nitride photocatalysis co_(2)reduction modification

Wedge-shaped HfO_(2) buffer layer-induced field-free spin-orbit torque switching of HfO_(2)/Pt/co structure

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Chinese Physics B 2024年第4期33卷 662-667页

作者：陈建辉梁梦凡宋衍袁俊杰张梦旸骆泳铭王宁宁 School of Electronics and Information Engineering Hangzhou Dianzi UniversityHangzhou 310018China covestro lnvestment co. LtdShanghai 200126China

Field-free spin-orbit torque(SOT)switching of perpendicular magnetization is essential for future spintronic *** study demonstrates the field-free switching of perpendicular magnetization in an HfO_(2)/Pt/co/TaO_(x) structure,which is facilitated by a wedge-shaped HfO_(2)buffer *** field-free switching ratio varies with HfO_(2)thickness,reaching optimal performance at 25 *** phenomenon is attributed to the lateral anisotropy gradient of the co layer,which is induced by the wedge-shaped HfO_(2)buffer *** thickness gradient of HfO_(2)along the wedge creates a corresponding lateral anisotropy gradient in the co layer,correlating with the switching *** findings indicate that field-free SOT switching can be achieved through designing buffer layer,offering a novel approach to innovating spin-orbit device.

关键词： spin-orbit torque field-free switching HfO_(2) buffer layer

Preferential adsorption control: Ca-based LDO for regenerating used lubricating oil

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Progress in Natural Science:Materials International 2024年第1期34卷 155-161页

作者： Xiao-lei Zhang Jian-zhong Wu Yun Liu Zai-wu Zhang Chao Hu Yong-sheng Lu School of Environmental and Chemical Engineering Shanghai University Shanghai Chengtou Wastewater Treatment co. LTD Shanghai Shangsheng Ecological Engineering co. Ltd. Shencai Technology co. Ltd

Different Ca-based layered double oxides（LDO） were applied in the removal of contaminants in used lubricating oil as an alternative decolorant. CaAl-LDO and CaFeAl-LDO achieved much greater decoloration efficiency than the traditional decolorants, where 0.93 and 0.91 of the decoloration efficiency under the optimum conditions were obtained, respectively. The decoloration activity with CaFeAl-LDO > CaAl-LDO >> CaFe-LDO was revealed by both Density Functional Theory（DFT） calculations and experimental analysis. Ca12Al14O33was shown to be the active component for decoloration. Fe3+doped into CaAl-LDO could improve decoloration activity via a changed charge distribution of decolorant. High preferential adsorption activity, which originated from different charge distribution for contaminants instead of the oil components, contributed to outstanding decoloration performance. The activity depended on the adsorption intensity of contaminants, where the most of the active decolorant neither too strongly or weakly bound with the contaminants. The results of this study suggested the Cabased LDOs could be a potentially alternative decolorants for regenerating the used lubricating oil.

关键词： Used lubrication oil Adsorption Ca-LDO Decoloration DFT calculation