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Controlling the Reactivity of IBA-N_(3)by Switching Halogen Salts:Providing a Universal Strategy for Haloazidation of Alkenes

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Chinese Journal of Chemistry 2024年第16期42卷 1839-1845页

作者： Chen-Xi Xia Xin-Lei Sun Jinfeng zhang yue ren Yan Yu Kuai Wang Ling-guo Meng Key Laboratory of Green and Precise Synthetic Chemistry and Applications Ministry of Education/School of Chemistry and Materials ScienceHuaibeiNormal UniversityHuaibeiAnhui 235000China

Although various routes have been reported for haloazidation,unavoidable problems exist,such as environmentally unfriendly monomer halogen,the need for in situ generation of unstable halogen azides(XN3),applicability to one type of haloazidation and inability to precisely control ***,we developed a universal strategy for haloazidation of alkenes through controlling the reactivity of IBA-N_(3) by switching halogen salts,allowing for the synthesis of a diversity of halogen azide *** studies have shown that by tuning the reactivity of IBA-N_(3) via switching halogen salts,different intermediates can be controllably produced to achieve regioselectivityand chemoselectivity in thehaloazidationof alkenes.

关键词： Haloazidation Alkene IBA-N_(3) Halogen salts Difunctionalization Selectivity Radicals Synthetic methods

Enhanced bright green luminescence from GdOF:Ho^(3+) up-conversion phosphor via Yb^(3+) doping

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Journal of Rare Earths 2024年第2期42卷 263-269,I0002页

作者： Linjun Qin yue guo Jing Xu Lixi Wang Qitu zhang College of Materials Science and Engineering Nanjing Tech UniversityNanjing211816China

In this paper,a series of GdOF-based green phosphors doped with Ho^(3+) and Yb^(3+) ions was prepared by a simple co-precipitation *** crystal structure s and optical prope rties were investigated in *** intensity of the emission of GdOF:Yb^(3+),Ho^(3+) phosphors is enhanced by the effective energy transfer from Yb^(3+) to Ho^(3+),and the optimal luminescence is achieved with the Ho^(3+)doping amount of 0.1 mol%as well as Yb^(3+) doping amount of 5 mol%.Tunable UC emission of samples is achieved by adjusting the doping concentration of Ho^(3+) or Yb^(3+).The purity of the green UC emission is further improved by enhancing the excitation pumping *** addition,logarithmic functions of green,red and nearinfrared radiation intensities were calculated versus logarithmic function of pump power for further study.A possible UC luminescence mechanism between Yb^(3+) and Ho^(3+) is discussed based on powerdependent UC luminescence spectrum and decay *** results suggest that GdOF:Yb^(3+),Ho^(3+)phosphors with bright and high-purity green UC emission have potential applications in the fields of bioimaging,display and illumination.

关键词： Up-conversion GdOF Lanthanide ions Rare earths

Significant effect of ordered micro-domain on cell boundary phase distribution and demagnetization curve squareness of Sm_(2)Co_(17)-type magnet

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Rare Metals 2024年第4期43卷 1724-1735页

作者： Zhuang Liu Hai-Chen Wu Chao-yue zhang Chao-Qun Zhu guo-Xin Chen Huan-Ming Lu ren-Jie Chen Aru Yan CISRI&NIMTE Joint Innovation Center for Rare Earth Permanent Magnets Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China University of Chinese Academy of Sciences Beijing100049China Analytical Center Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo315201China

Cu-rich cell boundary phase is difficult to precipitate evenly,resulting in a generally poor demagnetization curve squareness for Fe-rich Sm_(2)Co_(17)-type magnet,which is a key factor limiting the further improvement of magnetic energy *** this study,we report that nanoscale strip-like ordered micro-domains distributed in1:7H disordered matrix phase of the solid solution precursor is a new factor significantly affecting the precipitation and distribution of the cell boundary *** strip-like and continuous micro-twin structure with twin boundaries neatly perpendicular to the C-axis is observed after sintering *** solution treatment,sequential and long strip-like micro-twins gradually transform into disordered state along the basal plane,forming narrow disordered 1:7H(TbCu_(7)-type structure)phase between the separated strip-like ordered *** disordering transformation takes place via broken down of the long strip-like ordered micro-domains,which is accomplished by narrowing along the width direction followed by reduction of the ***,a new model revealing the effect of the ordered micro-domains on the formation of the cell boundary phase is *** boundaries enriched in Cu have already existed in the precursor with long strip-like ordered ***,the Cu-rich cell boundary phase acting as strong pinning centers cannot be precipitated homogeneously and distributed continuously after aging,resulting in a poor demagnetization curve squareness of Sm_(2)Co_(17)-type *** results indicate that significant broken down of the nanoscale ordered micro-domains in solution precursor is the key factor improving the distribution of cell boundary phase in Sm_(2)Co_(17)-type magnets.

关键词： Sm_(2)Co_(17) magnets Solution precursor Ordered micro-domains Disordering transformation Cellular structure

Aggregation of CeAlO_(3) inclusions in heavy ingot of a steel containing 0.007% aluminum

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Journal of Iron and Steel Research International 2024年第8期31卷 1960-1972页

作者： Qiu-yue Zhou Jun-tao Ba Lun zhang Wei Chen Ying ren Li-feng zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The distribution of inclusions at the bottom of a Ce-treated heavy steel ingot was detected and *** three-dimensional morphology and spatial distribution of CeAlOs clusters were characterized using the electrolytic extraction and Micro-CT detection.A model of inclusion collision to predict the aggregation of CeAlO_(3) inclusions in the ingot was established and validated by measured *** were mainly CeAlO_(3) and a small amount of Ce_(2)O_(2)S in the tundish after cerium *** collision and aggregation of inclusions led to the formation of large clusters in the ingot during the solidification *** slag entrainment inclusions,large CeAO_(3) clusters and small CeAlO_(3) particles were observed from the center to the edge of the ingot *** inclusions were mainly concentrated at the *** number density of inclusions larger than 200μm was 0.21 mm^(-3).The maximum diameter of CeA1O_(3) clusters was 1340μ*** the edge to the radial center and from the bottom to the top,the average diameter of inclusions gradually increased due to the longer solidification time of the ingot.

关键词： Inclusion Heavy ingot Cerium treatment Collision

Ti_(3)C_(2)T_(x)/SnO_(2)P–N heterostructure construction boosts room-temperature detecting formaldehyde

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Rare Metals 2024年第1期43卷 267-279页

作者： yue zhang Ming-yue Wang Xiao-Guang San Yan-Bai Shen guo-Sheng Wang Lei zhang Dan Meng College of Chemical Engineering Shenyang University of Chemical TechnologyShenyang 110142China Institute for Superconducting and Electronic Materials(ISEM) Australian Institute for Innovative Materials(AIIM)University ofWollongongWollongongNSW2500Australia College of Resources and Civil Engineering Northeastern UniversityShenyang 110819China

Formaldehyde is a common atmospheric pollutant produced in industrial production and daily ***,the traditional semiconductor formaldehyde gas sensor cannot work at room temperature,which limits its practical ***,developing high-performance gas sensors for rapidly and accurately detecting formaldehyde at room temperature is an important *** this study,Ti_(3)C_(2)Tx/SnO_(2)heterostructures were constructed,which could selectively detect formaldehyde at room temperature with a response value of 29.16%(10×10^(-6)).In addition,the sensor shows a remarkable theoretical detection limit of 5.09×10^(-9)and good longterm *** functional theory(DFT)simulations reveal that SnO_(2)nano spheres provide the majority of adsorption sites that strongly interact with ***,Ti_(3)C_(2)T_(x)acting as a conductive layer facilitates the transfer of charge carriers so that they show a sensing response to formaldehyde at room ***,the formation of p-n heterostructures between SnO_(2)and Ti_(3)C_(2)T_(x)boosts the Schottky barrier at the interface,which is the critical factor in enhancing the sensing properties by turning the Schottky barrier upon introducing formaldehyde *** perspective is expected to provide instructive guidance for utilizing MXene/metal oxide nanocomposites to improve the gas sensing performance at room temperature.

关键词： Ti_(3)C_(2)T_(x)/SnO_(2)nanocomposites p-n heterostructures Formaldehyde sensing Room temperature DFT calculations

A model reduction approach for discrete-time linear time-variant systems with delayed inputs

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Science China(Information Sciences) 2024年第4期67卷 197-217页

作者： Ai-guo WU Guang-ren DUAN Yu WANG Jie zhang School of Mechanical Engineering and Automation Harbin Institute of Technology(Shenzhen) HIT Wuhu Robot Technology Research Institute Center for Control Science and Technology Southern University of Science and Technology

A model reduction approach is presented for discrete-time linear time-variant input-delayed systems. According to this proposed approach, a dynamical variable is constructed by taking advantage of the current state and historical information of input. It is revealed that the behavior of this dynamical variable is governed by a discrete-time linear delay-free system. It is worth noting that the presented variable transformation does not require the system matrix to be invertible. Based on the reduced delay-free models,stabilizing control laws can be easily obtained for the original delayed system. For the case with a single input delay, the constructed variable is an exact prediction for the future state, and thus the stabilizing control law could be designed by replacing the future state with its prediction. Finally, three discrete-time periodic systems with delayed input are employed to illustrate how to utilize the presented model reduction approaches.

关键词： reduction approach predictor-based feedback time-varying systems delayed input periodic system

Rational design of new in situ reduction of Ni(II)catalytic system for low-cost and large-scale preparation of porous aromatic frameworks

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Carbon Energy 2024年第5期6卷 105-113页

作者： Shanshan Wang yue Wu Wenxiang zhang Hao ren Guangshan Zhu Heping Ma School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'anChina State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchunChina College of Chemistry Northeast Normal UniversityChangchunChina

Porous aromatic framework 1(PAF-1)is an extremely representative nanoporous organic framework owing to its high stability and exceptionally high surface ***,the synthesis of PAF-1 is catalyzed by the Ni(COD)2/COD/bpy system,suffering from great instability and high ***,we developed an in situ reduction of the Ni(II)catalytic system to synthesize PAF-1 in low cost and high *** active Ni(0)species produced from the NiCl_(2)/bpy/NaI/Mg catalyst system can effectively catalyze homocoupling of tetrakis(4-bromophenyl)methane at the room temperature to form PAF-1 with high Brunauer-Emmett-Teller(BET)-specific surface area up to 4948 m^(2) g^(−1)(Langmuir surface area,6785 m2 g−1).The possible halogen exchange and dehalogenation coupling mechanisms for this new catalytic process in PAF's synthesis are discussed in *** efficiency and universality of this innovative catalyst system have also been demonstrated in other PAFs'*** work provides a cheap,facile,and efficient method for scalable synthesis of PAFs and explores their application for high-pressure storage of Xe and Kr.

关键词： adsorption carbon material nickel catalysis porous aromatic framework porous organic polymer

Insights into the history and tendency of glycosylation and digestive system tumor:A bibliometric-based visual analysis

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 1059-1075页

作者： Jie Jiang Zai Luo ren-Chao zhang yue-Ling Wang Jun zhang Ming-Yu Duan zheng-Jun Qiu Chen Huang Department of Gastrointestinal Surgery Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China Jiangnan University Wuxi School of Medicine Wuxi 214122Jiangsu ProvinceChina Department of Education Shanghai General HospitalShanghai Jiao Tong University School of MedicineShanghai 200080China

BACKGROUND Glycosylation,a commonly occurring post-translational modification,is highly expressed in several tumors,specifically in those of the digestive system,and plays a role in various cellular pathophysiological *** the importance and detection methods of glycosylation in digestive system tumors have garnered increasing attention in recent years,bibliometric analysis of this field remains *** present study aims to identify the developmental trends and research hotspots of glycosylation in digestive system *** To find and identify the developmental trends and research hotspots of glycosylation in digestive system *** We obtained relevant literature from the Web of Science Core Collection and employed VOSviewer 1.6.19 and CiteSpace(version 6.1.R6)to perform bibliometric *** A total of 2042 documents spanning from 1978 to the present were analyzed,with the research process divided into three phases:the period of obscurity(1978-1990),continuous development period(1991-2006),and the rapid outbreak period(2007-2023).These documents were authored by researchers from 66 countries or regions,with the United States and China leading in terms of publication *** Celso A had the highest number of publications,while Pinho SS was the most cited ***-occurrence analysis revealed the most popular keywords in this field are glycosylation,expression,cancer,colorectal cancer,and pancreatic ***,the Journal of Proteome Research was the most prolific journal in terms of publications,while the Journal of Biological Chemistry had the most *** The bibliometric analysis shows current research focus is primarily on basic research in this ***,future research should aim to utilize glycosylation as a target for treating tumor patients.

关键词： Glycosylation Cancer Digestive system Bibliometric analysis CiteSpace VOS viewer

Do companies influenced by smart cities pay more attention to green governance?Mechanism and optimal spatial correlation

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Chinese Journal of Population,Resources and Environment 2024年第1期22卷 48-57页

作者： Xiaoxu guo Rao zhang yue zhang College of Finance Nanjing Agricultural UniversityNanjing 210095China

Smart cities are a way for China to construct an innovative and environmentally conscious *** paper examines the impact of smart cities on corporate green governance and provides a theoretical foundation for formulating and executing smart city policy in *** on panel data from Chinese A-share listed companies in Shanghai and Shenzhen from 2008 to 2020,this study constructs a multiperiod double-difference model to examine the influence of smart cities on corporate green ***,it uses a spatial double-difference model to investigate the spatial spillover effect of smart cities on neighboring *** findings indicate that smart cities effectively enhance corporate green *** the influencing mechanisms reveals that resource allocation efficiency,technological innovation,management environmental awareness,and regional environmental enforcement efforts act as ***,the study reveals that the impact of smart cities on promoting corporate green governance is more pronounced in regions with lower levels of marketization and resource-based ***,the research explores the spatial spillover effects of smart cities,with an effective radius of approximately 350 *** optimal spatial correlation zone for green governance of businesses in neighboring areas in relation to smart cities is within a range of 250-350 *** is manifested by the significant promotion of green governance in neighboring area businesses facilitated by smart cities.

关键词： Smart cities Corporate green governance Mediating effects Spatial associations