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云南化工 2023年第3期50卷 117-120页

作者：孙晓宇呼伦贝尔金新化工有限公司内蒙古呼伦贝尔021000

结合金新壳牌(Shell)下行水激冷气化炉灰水系统带渣期间工况的异常变化,探讨带渣对装置稳定运行造成的影响,分析灰水系统带渣的原因,并提出相应的处理方案及调整思路,为今后的装置运行维护及优化调整提供一定的参考。

关键词： Shell 下行水激冷灰水系统带渣

Mantle Response to Slab Breakoff in the North Qaidam Tectonic Belt: Geochemical Constraints from Syn-subduction Mafic Igneous Rocks

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Acta Geologica Sinica(English Edition) 2020年第S01期94卷 26-27页

作者： LI Xiucai NIU Manlan CAI Qianru WU Qi sun Yi YUAN xiaoyu LI Chen Hefei University of Technology Hefei Anhui 230009

Slab breakoff originally denotes the detachment of dense subducted oceanic slab from the light subducted continental slab, which is driven by opposing buoyancy forces during continental collision(Davies and von Blanckenburg, 1995;von Blanckenburg and Davies, 1995). The breakoff of subducted oceanic slab can induce the upwelling of sub-slab asthenosphere through the slab window, and then heat the overriding lithospheric mantle resulting in the melting of its fertile layer within the metasomatic mantle wedge. The decompression partial melting of uprising asthenospheric mantle commonly produce mafic magma with depleted MORB-like geochemical signatures(Davies and von Blanckenburg, 1995;Cole et al., 2006;Wang et al., 2018), whereas the partial melting of enriched lithospheric mantle will produce mafic magma with alkaline, calc-alkaline or ultrapotassic features(von Blanckenburg and Davies, 1995). These mafic magmas rise into overlying lower crust and trigger crustal melting to generate the granitic magma. The North Qaidam tectonic belt(NQTB) records the evolutionary process of the South Qilian Ocean from subduction to closure. The subduction of oceanic and continental lithosphere to mantle depths is proven by the identification of oceanic-type and continental-type eclogites enclosed in crustal metapelite and gneiss from the North Qaidam tectonic belt(Song et al., 2006;Zhang et al., 2008;Zhang et al., 2010;Zhang et al., 2017). However, details of this process are not exactly constrained, in particularly, the closure timing of South Qilian Ocean. The study of characteristic mafic magmatism, combined with the previous studies of ultra-high pressure metamorphism, give us an excellent opportunity to trace the detailed processes associated with the transition from oceanic subduction to continental subduction, and assess the feasibility of slab breakoff in the North Qaidam tectonic belt. In this contribution, an integrated study of petrology, geochemistry, geochronology and Sr-Nd-Hf isotopes is performed on the mafic igneous

关键词： mafic igneous rocks mantle slab break-off North Qaidam early Paleozoic

Effect of cooling rate on phosphorus segregation behavior and the corresponding precipitation of γ’’ and γ’ phases in IN718 alloy

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Journal of Materials Science & Technology 2019年第7期35卷 1485-1490页

作者： Anwen Zhang Sha Zhang Fang Liu Feng Qi xiaoyu Yao Yuanguo Tan Dan Jia Wenru sun Institute of Metal Research Chinese Academy of SciencesShenyang 110016China College of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China

Effect of segregation behaviors of P at different cooling rates on the precipitation of γ" and γ' phases and the corresponding strength are investigated. The precipitation of γ" and γ' phases during cooling is sensi-tive to P concentration. With increasing the concentration of Pf the amount of γ" and γ' particles increases after air cooling. With decreasing the cooling rate, the accelerating effect of P on the precipitation of γ" and γ' phases decreased first and then increased, which demonstrates the concentration of P dissolved in the grain interior decreases first and then increases. The different effects of P on γ"and γ' phases with different cooling rates were analyzed by the kinetic characteristic of nonequilibrium grain-boundary seg-regation. The characteristic of nonequilibrium grain-boundary segregation of P in superalloy is further confirmed, and the phenomenon caused by critical cooling rate is captured.

关键词： Phosphorus IN718alloy Segregation behavior γ" and γ' phases

Safety Verification of Semi-Algebraic Dynamical Systems via Inductive Invariant

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Tsinghua Science and Technology 2014年第2期19卷 211-222页

作者： Hui Kong Fei He xiaoyu Song Ming Gu Hongyan Tan Jiaguang sun the School of Software Tsinghua University the Department of ECE Portland State University the Institute of Acoustics Chinese Academy of Sciences

To verify the safety of nonlinear dynamical systems based on inductive invariants, key issues include defining the most complete inductive condition and discovering an inductive invariant that satisfies the specified inductive condition. In this paper, to lay a solid foundation for future research into the safety verification of semi- algebraic dynamical systems, we first establish a formal framework for evaluating the quality of continuous inductive conditions. In addition, we propose a new complete and computable inductive condition for verifying the safety of semi-algebraic dynamical systems. Compared with the existing complete and computable inductive condition, this new inductive condition can be easily adapted to achieve a set of sufficient inductive conditions with different level of conservativeness and computational complexity, which provides us with a means to trade off between the verification power and complexity. These inductive conditions can be solved by quantifier elimination and SMT solvers.

关键词： inductive invariant semi-algebraic dynamical system safety verification hybrid system nonlinearsystem

Catalytic PtPd bimetal nanocrystals with high-index facets for radiation injury repair

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Chinese Chemical Letters 2020年第1期31卷 269-274页

作者： Wei Long Jingya Wang Fujuan Xu Hongying Wu xiaoyu Mu Junying Wang Yuanming sun Xiao-Dong Zhang Key Laboratory of Tianjin Radiation and Molecular Nuclear Medicine Institute of Radiation MedicineChinese Academy of Medical Sciences and Peking Union Medical CollegeTianjin 300192China Department of Physics and Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology School of ScienceTianjin UniversityTianjin 300350China

Radiotherapy is one of the most important clinical cancer treatments,which works mainly by delive ring a prescribed radiation dose to the tumor tissues.However,high doses of radiation may also lead many irreversible damages to the surrounding normal tissues.Thereby,how to effectively reduce these sideeffects has been a significant factor in influencing cancer therapeutic effect.In this work,we synthesized the hollow PtPd nanocubes with high-index facets,and investigated the radiation protection capability in vitro and in vivo.Our results showed the PtPd nanocrystals can decrease the ROS level and improve the survival rate of radiated cells.Meanwhile,survival rate of radiated mice can significantly increase from 0 to 30%after PtPd treatment.Consequently,the enzyme and ROS level in radiated mice can be recovered.

关键词： Radiation protection Nanocrystals High-index facets Bimetal Radiation injury

A dynamic regulation of nitrogen on floret primordia development in wheat

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The Crop Journal 2024年第1期12卷 271-280页

作者： Zhen Zhang Yujing Li Yuxun Wu xiaoyu Zheng Xiaolei Guo Wan sun Zhencai sun Zhimin Wang Yinghua Zhang College of Agronomy and Biotechnology China Agricultural UniversityBeijing 100193China College of Biological Sciences China Agricultural UniversityBeijing 100193China Engineering Technology Research Center for Agriculture in Low Plain Areas Cangzhou 061800HebeiChina

Nitrogen(N)fertilization is critical for spike and floret development,which affects the number of fertile florets per spike(NFFs).However,the physiological regulation of the floret development process by N fertilization is largely unknown.A high temporal-resolution investigation of floret primordia number and morphology,dry matter,and N availability was conducted under three N fertilization levels:0(N0),120(N1)and 240(N2)kg ha^(−1).Interestingly,fertile florets at anthesis stage were determined by those floret primordia with meiotic ability at booting stage:meiotic ability was a threshold that predicted whether a floret primordium became fertile or abortive florets.Because the developmental rate of the 4th floret primordium in the central spikelet was accelerated and then they acquired meiotic ability,the NFFs increased gradually as N application increased,but the increase range decreased under N2.There were no differences in spike N concentration among treatments,but leaf N concentration was increased in the N1 and N2 treatments.Correspondingly,dry matter accumulation and N content of the leaf and spike in the N1 and N2 treatments was increased as compared to N0.Clearly,optimal N fertilization increased leaf N availability and transport of assimilates to spikes,and allowed more floret primordia to acquire meiotic ability and become fertile florets,finally increasing NFFs.There was no difference in leaf N concentration between N1 and N2 treatment,whereas soil N concentration at 0–60 cm soil layers was higher in N2 than in N1 treatment,implying that there was still some N fertilization that remained unused.Therefore,improving the leaf’s ability to further use N fertilizer is vital for greater NFFs.

关键词： Fertile florets Floret primordia Grain number Meiotic ability Morphological development

Optimization of both coercivity and knee-point magnetic field of Sm2Co17-type magnets via solid solution process

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Journal of Rare Earths 2020年第11期38卷 1224-1230,I0003页

作者： Shuai Wang Yikun Fang Kuikui Song xiaoyu Zhu Lei Wang Wei sun Wei Pan Minggang Zhu Wei Li Division of Functional Materials Research Central Iron and Steel Research InstituteBeijing 100081China National Engineering Research Center for Magnetic Materials Beijing 102600China

It is confirmed that phase homogenization is very important for improving the magnetic properties of 2:17-type Sm-Co sintered magnets,In this work,the influence of solid solution process on microstructure and magnetic properties of the Sm(CobalFe0.233Cu0.073Zr0.024)7.6 sintered magnets was systematically studied.With the solid-solution treating duration(tS)increasing from 0 to 4 h,intrinsic coercivity(Hcj)increases from 12.83 to 36.54 kOe,magnetic field at knee-point(Hknee)increases from2.76 to 19.14 kOe,and the maximum energy product increases from 19.79 to 29.48 MGOe.The electron probe microanalyzer results reveal that there mainly exist gray and dark regions besides"white"rare earth-rich phase,and the conte nt of Sm,Fe and Cu elements for the two kinds of regions changes a lot for the specimens,Furthermore,with tS increasing up to 4 h,the elements content deviation between the gray and dark regions becomes small gradually from 3.94 at%to 0.27 at%,7.66 at%to 0.21 at%and 7.27 at%to 0.16 at%for Sm,Fe and Cu elements,respectively.Moreover,transmission electron microscopy results show that the distribution of cell size is much more concentrated for aged specimens when tS is 4 h.It is also found that the Cu concentration at cell boundaries for the 4 h solid-solution treatment case shows relatively higher values and greater concentration gradient(1.94 at%/nm).It is verified that sufficient solution treatment duration is prerequisite to form these homogeneous microstructural features,which are the key points for obtaining both high Hcj and Hknee.

关键词： Sm-Co magnets Solid solution process Coercivity Microstructure Cell size Rare earths

Synthesis of bis(amino)furans from biomass based 5-hydroxymethyl furfural

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Journal of Energy Chemistry 2018年第1期27卷 209-214页

作者： xiaoyu Wang Wei Chen Zheng Li Xianhai Zeng Xing Tang Yong sun Tingzhou Lei Lu Lin College of Energy Xiamen UniversityXiamen 361102FujianChina Xiamen Key Laboratory of High-valued Conversion Technology of Agricultural Biomass Xiamen UniversityXiamen 361102FujianChina Henan Key Laboratory of Biomass Energy Zhengzhou 450008HenanChina

In this study we report a new reaction pathway in which the hydroxyl and the aldehyde groups of 5-hydroxymethyl furfural were aminated respectively. Hydroxyl group was aminated via Ritter reaction followed by direct reductive amination of aldehyde group. For the Ritter reaction of 5-hydroxymethyl furfural, mixture of trifluoromethane sulfonic acid and phosphoric anhydride showed good performance and the intermediate N-acyl-5-aminomethyl furfural with the highest yield of 89.1 wt% was obtained.Optimization of direct reductive amination of 2,5-bis（aminomethyl） furan was conducted and a yield of45.7 wt% was achieved. This study presents a simple way for preparing bis（amino）furans from renewable biomass based 5-hydroxymethyl furfural, which enriches the biorefinery concept from biomass.

关键词： 5-Hydroxymethyl furfuralN-Acyl-5-aminomethyl furfura2,5-bis（Aminomethyl） furanRitter reactionReductive amination

Excitation orthogonalized upconversion nanoprobe for instant visual detection of trinitrotoluene

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Nano Research 2023年第1期16卷 1491-1499页

作者： Xu Li Xu Zhao xiaoyu Xu Yang Lu Jiahang Wu Fangmeng Liu Xu Yan Peng sun Chenguang Wang Xianggui Kong Xiaomin Liu Geyu Lu State Key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchun 130012China Department of Public Security of Jilin Province Changchun 130051China State Key Laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and physicsChinese Academy of ScienceChangchun 130033China

Excitation-emission orthogonalized luminescent upconversion nanoparticles(OUCNPs),which can respond to changes in external stimuli accordingly,show great promise in many intelligent applications.However,the construction of such materials mostly relies on the selective absorption of Nd3+and Yb3+at different wavelengths and the long-range energy migration between the layers,resulting in complex structures and limited orthogonal luminescence intensity.Herein,we developed a relatively simple structure of OUCNPs(β-NaErF4@NaLuF4@NaYF4:20%Yb,2%Er@NaLuF4),where the fluorescence emission switches from red to green when the excitation wavelength is shifted from 808 to 980 nm.This structure exhibits high-quality,independent,and non-interfering orthogonal luminescence properties without Nd3+sensitization and long-range energy migration.As a proof of concept,we demonstrate the application of the designed OUCNPs in anti-counterfeiting.We also prepared OUCNPs@PEI(PEI=polyethylenimine)self-referencing fluorescent probes to enable quantitative analysis of trinitrotoluene(TNT)in solution with a detection limit of 3.04μM.The probes can be made into test strips for portable on-site visual detection of TNT,and can also be used to image latent fingerprints and detect explosive residues in fingerprints simultaneously.The concept proposed in this work can be extended to the visual detection of a larger range of organic and biological molecules,and is highly promising for practical applications.

关键词： orthogonal luminescence NaErF4 core/multi-shell structure anti-counterfeiting trinitrotoluene(TNT)detection

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一种应用于CPE的低剖面双频圆极化天线

无线电工程 2023年第10期53卷 2375-2379页

作者：张小雨孙虎成南京信息工程大学应用电磁学研究中心江苏南京210044 南京信息工程大学江苏省大气环境与装备技术协同创新中心江苏南京210044

针对客户终端设备(Customer Premise Equipment,CPE)的应用需求,设计了一种低剖面双频圆极化天线。在2.45 GHz,采用了4个偶极子单元阵列产生水平极化全向辐射,并采用内部接地圆环贴片结构产生垂直极化全向辐射。将两部分结构通过耦合器... 详细信息

针对客户终端设备(Customer Premise Equipment,CPE)的应用需求,设计了一种低剖面双频圆极化天线。在2.45 GHz,采用了4个偶极子单元阵列产生水平极化全向辐射,并采用内部接地圆环贴片结构产生垂直极化全向辐射。将两部分结构通过耦合器有效连接起来,从而产生了全向圆极化辐射特性。在5.8 GHz,采用了贴片结构产生了定向圆极化辐射特性。通过双工器将2个频段的结构合并起来,实现了低剖面双频圆极化天线。实测结果表明,天线在2个频段均有较好的圆极化辐射性能,验证了该天线设计的有效性。

关键词：客户终端设备圆极化双工器低剖面