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The role of mergers and gas accretion in black hole growth and galaxy evolution

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Research in Astronomy and Astrophysics 2021年第8期21卷 293-302页

作者： tian-Chi zhang qi Guo Yan Qu Liang Gao Key Laboratory for Computational Astrophysics National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Institute of Computational Cosmology Department of PhysicsUniversity of DurhamSouth RoadDurham DH13LEUK

We use a semi-analytic galaxy formation model to study the co-evolution of supermassive black holes(SMBHs) with their host *** the coalescence of SMBHs is not important,the quasarmode accretion induced by mergers plays a dominant role in the growth of *** play a more important role in the growth of SMBH host galaxies than in the SMBH *** is the combined contribution from quasar mode accretion and mergers to the SMBH growth and the combined contribution from starburst and mergers to their host galaxy growth that determine the observed scaling relation between the SMBH masses and their host galaxy *** also find that mergers are more important in the growth of SMBH host galaxies compared to normal galaxies which share the same stellar mass range as the SMBH host galaxies.

关键词： methods:numerical galaxies:evolution (galaxies:)quasars:supermassive black holes

Facile Synthesis of Polyisothioureas via Alternating Copolymerization of Aziridines and Isothiocayanates

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Chinese Journal of Polymer Science 2024年第3期42卷 292-298,I0005页

作者： Hao-tian zhang Ming-Xin Niu qi zhang Chen-Yang Hu Xuan Pang Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Department of Materials Science and Engineering Jilin UniversityChangchun 130025China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Isothiourea is an important class of sulfur-containing molecules showing unique catalytic and biological activities. As such,polyisothiourea is envisioned to be an interesting type of polymer that potentially exhibits a number of interesting properties. However, there is no access to synthesizing well-defined polyisothiourea, and currently isothiourea-containing polymers are mainly prepared by immobilizing onto other polymer's side chain. Herein, we report the first facile synthesis of polyisothioureas via alternating copolymerization of aziridines and isothiocayanates. Mediated by the catalytic system of phosphazene superbases/alcohol, a broad scope of aziridines and isothiocayanates could be transformed into polyisothioureas with adjustable substitutions(11 examples). The structures of obtained polyisothioureas were fully characterized with ^(1)H-NMR, ^(13)C-NMR, and ^(1)H-^(13)C HMBC NMR. Moreover, the polyisothioureas show tunable thermal properties depending on substitutions on the isothiourea linkages. The novel structure of these polyisothioureas will enable a powerful platform for the discovery of nextgeneration functional plastics.

关键词： Polyisothioureas Alternative copolymer Aziridines Isothiocayanates

鄂南第四纪粘土红壤团聚体的稳定性及其稳定机制初探

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水土保持学报 2004年第4期18卷 69-72页

作者：李朝霞蔡崇法史志华王天巍张琪孙站成华中农业大学资源与环境学院武汉430070

用湿筛法和LeBissonnais法研究了鄂南第四纪红粘土母质发育的两种侵蚀程度的红壤团聚体的稳定性,并且分析了影响供试土壤团聚体稳定性的土壤性质。结果表明,轻度侵蚀的耕作土壤团聚体的稳定性较低,在水的作用下易崩解成较小粒径的水稳... 详细信息

用湿筛法和LeBissonnais法研究了鄂南第四纪红粘土母质发育的两种侵蚀程度的红壤团聚体的稳定性,并且分析了影响供试土壤团聚体稳定性的土壤性质。结果表明,轻度侵蚀的耕作土壤团聚体的稳定性较低,在水的作用下易崩解成较小粒径的水稳性团聚体;强度侵蚀的土壤表层团聚体的稳定性较高,崩解后产生较多的水稳性大团聚体。引起土壤团聚体破坏的主要作用机制是土壤团聚体中的闭蓄空气爆破引起的消散作用;研究区第四纪红壤团聚体的主要胶结物质是土壤中的粘粒、游离氧化铁铝和无定形铁。由于供试土壤中有机质含量很低,在本研究中,有机质含量与土壤团聚体稳定性之间没有显著正相关关系。

关键词：鄂南地区第四纪粘土红壤团聚体稳定性稳定机制

A Note on Determine the Greatest Common Subfamily of Two NFSRs by Grbner Basis

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Journal of Systems Science & Complexity 2015年第5期28卷 1231-1242页

作者： WANG Zhongxiao qi Wenfeng tian tian Luoyang University of Foreign Language State Key Laboratory of Mathematical Engineering and Advanced Computing Zhengzhou Information Science and Technology Institute

For nonlinear feedback shift registers(NFSRs), their greatest common subfamily may be not unique. Given two NFSRs, the authors only consider the case that their greatest common subfamily exists and is unique. If the greatest common subfamily is exactly the set of all sequences which can be generated by both of them, the authors can determine it by Grbner basis theory. Otherwise, the authors can determine it under some conditions and partly solve the problem.

关键词： Greatest common subfamily Grbner basis nonlinear feedback shift register stream cipher

单一及多组分混合物绿松石仿制品的光谱学特征研究

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光谱学与光谱分析 2025年第1期45卷 183-190页

作者：杨池玉汪田田张维肖汤维茜同济大学浙江学院浙江嘉兴314051

对市场新出现的一类仿制品进行了拉曼光谱、红外光谱、化学成分、紫外-可见-近红外吸收光谱分析,对其主要谱学特征进行了归纳总结。结果表明这类仿制品主要由重晶石、三水铝石、方解石粉末单一组分或多组分混合压制再经环氧树脂类或丙... 详细信息

对市场新出现的一类仿制品进行了拉曼光谱、红外光谱、化学成分、紫外-可见-近红外吸收光谱分析,对其主要谱学特征进行了归纳总结。结果表明这类仿制品主要由重晶石、三水铝石、方解石粉末单一组分或多组分混合压制再经环氧树脂类或丙烯酸酯类有机物胶结,并经人工染剂染色而成。红外光谱显示:单一矿物组分仿制品和绿松石差异明显,重晶石仿制品显示[SO_(4)]^(2-)的1078 cm^(-1)吸收峰等,方解石仿制品显示[CO_(3)]^(2-)的1476±cm^(-1)吸收峰等;多组分仿制品可见综合了多种矿物特征的吸收光谱,谱学特征复杂。根据缺失水峰,或仅显示三水铝石结构水OH-导致的3623、3528、3472和3388 cm^(-1)吸收峰,指纹区显示[SO_(4)]^(2-)、[CO_(3)]^(2-)相关吸收峰,可初步区分于绿松石。显微拉曼光谱测试结果表明多组分仿制品的不同测试位置矿物组成不同,可分别测试到三水铝石(3360、3432、3522、3614 cm^(-1))、重晶石(989 cm^(-1))、方解石(1088 cm^(-1))的特征峰,结合显微拉曼光谱及化学分析结果可进一步确认仿制品的具体矿物组成。紫外-可见-近红外吸收光谱表明样品均经人工染剂染色,显示633±、713±nm吸收宽峰或610±、675±nm吸收宽峰。

关键词：三水铝石重晶石方解石振动光谱微区分析

A New Distinguishing Attack on Grain-V1 with 111 Initialization Rounds

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Journal of Systems Science & Complexity 2019年第3期32卷 970-984页

作者： MA Zhen tian tian qi Wenfeng National Digital Switching System Engineering & Technological Research Center

The Grain-v1 stream cipher has been selected in the eSTREAM hardware finalists. In this paper, the authors derive a new distinguishing attack on Grain-v1 with 111 initialization rounds in a single-key setting. To achieve this goal, the authors present two delicate strategies targeting an obvious distinguishing probability of the output difference of reduced Grain-v1. The authors show that conditional differential cryptanalysis of reduced Grain-v1 with 111 initialization rounds could mount a distinguishing attack with success probability about 0.8281 for all secret keys. It is also shown that when the attacking round further increases to 112 and 113, the distributions of the output differences are nearly random. Thus far, to the best of the authors' knowledge, the attack on Grain-v1 with 111 initialization rounds is the best single-key cryptanalytic result for reduced versions of Grain-vl in terms of the number of attacking rounds.

关键词： Cryptanalysis differential cryptanalysis distinguishing attack Grain-v1 stream cipher

On Characteristic Functions of De Bruijn Sequences

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Chinese Journal of Electronics 2016年第2期25卷 304-311页

作者： TANG Zhenwei qi Wenfeng tian tian Department of Applied Mathematics Zhengzhou Information Science and Technology Institute

In 1982, H. Fredricksen presented the upper and lower bounds of the number of ones in the truth table of characteristic functions of de Bruijn sequences. In this paper, the distribution of ones in the truth table of characteristic functions of de Bruijn sequences is further studied. We provide the upper and lower bounds of the number of ones in the partial truth table of characteristic functions of de Bruijn sequences. Furthermore, the two bounds are tight.

关键词： Nonlinear feedback shift registers De Bruijn sequences Weight of the truth table

The neural mechanisms of vital loss emotions

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Chinese Science Bulletin 2014年第16期59卷 1856-1863页

作者： Yue qi qi Li Moqian tian Bibing Dai Kan zhang Key Laboratory of Behavioral Science Institute of PsychologyChinese Academy of Sciences University of Chinese Academy of Sciences Institute of Psychology Tianjin Medical University

This paper clarified the definition of vital loss emotions and summarized three contributing constituent elements through the review of previous research on vital loss *** on the results from relevant clinical,neuroimaging and electrophysiological studies,we further noted the advantages and disadvantages of previous research and discussed the neural network model of vital loss emotions to propose future research *** the research on vital loss emotions has generated significant results,it remains in its initial stages,and many questions are *** researchers would be encouraged to study real vital loss,dynamic longitudinal tracking and applied research on human health.

关键词：生命损失神经机制情绪神经网络模型构成要素研究人员人体健康动态跟踪

Physical and numerical investigation on fluid flow and inclusion removal behavior in a single-strand tundish

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Journal of Iron and Steel Research International 2023年第6期30卷 1182-1198页

作者： qi Quan Zhi-xiao zhang tian-peng Qu Xiang-long Li Jun tian De-yong Wang School of Iron and Steel Soochow UniversitySuzhou 215137JiangsuChina

Aiming at the problem that the existence of inclusions in the tundish continuous casting process can easily lead to quality defects of the slab,the stainless steel continuous casting tundish was taken as the research *** effects of flow control device,inclusion density and inclusion size on the mixing characteristics of molten steel and inclusion behavior in tundish were *** results showed that compared with the tundish without flow control device,the average residence time of molten steel was prolonged by about 49 s,the dead zone volume fraction was reduced by 8.93%,and the piston fluid integral rate was increased by 12.68%.In the turbulence inhibitor(TI)tundish with weir-dam combination,the removal rate of inclusions with a density of 2700 kg m^(-3) and a particle size of 5 lm is 63.32%,while the removal rate of large inclusions with a density of 150μm could reach 89.04%.When the inclusion particle size was 10-50μm and the density was 2700-4500 kg m^(-3),the effect of inclusion density on inclusion removal rate was *** the same time,when weir-dam combination TI tundish was set,the inclusions were mainly limited to the slag-metal interface of the first and second chambers of the *** removal rate of inclusions in the first chamber was generally improved,with 10μm inclusions accounting for 47.67% and 150μm inclusions accounting for 60.69%.Furthermore,it has the best effect on the removal of small-size inclusions,especially those less than 70μm.

关键词： Non-metallic inclusion Flow control device Residence time distribution curve Removal behavior Discrete particle model