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沉管隧道二次围堰施工技术

现代隧道技术 2011年第6期48卷 131-136,154页

作者：秦宝军中铁隧道股份有限公司郑州450000

沉管隧道二次围堰施工效果的好坏将直接影响到岸上主体结构施工时基坑的安全,关系到沉管隧道施工的工期、成本。文章简要介绍了沉管隧道二次围堰水下不分散混凝土施工技术。

关键词：沉管隧道二次围堰施工技术

Single atom doping induced charge-specific distribution of Cu1-TiO_(2)for selective aniline oxidation via a new mechanism

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Chinese Journal of Catalysis 2024年第9期64卷 98-111页

作者： Jiaheng qin Wantong Zhao Jie Song Nan Luo Zheng-Lan Ma baojun Wang Jiantai Ma Riguang Zhang Yu Long State Key Laboratory of Applied Organic Chemistry(SKLAOC) the Key Laboratory of Catalytic Engineering of Gansu ProvinceCollege of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou 730000GansuChina State Key Laboratory of Clean and Efficient Coal Utilization College of Chemical Engineering and TechnologyTaiyuan University of TechnologyTaiyuan 030024ShanxiChina

Utilizing single atom sites doping into metal oxides to modulate their intrinsic active sites,achieving precise selectivity control in complex organic reactions,is a highly desirable yet challenging ***,identifying the active site also represents a significant obstacle,primarily due to the intricate electronic environment of single atom site doped metal ***,a single atom Cu doped TiO_(2)catalyst(Cu_(1)-TiO_(2))is prepared via a simple“colloid-acid treatment”strategy,which switches aniline oxidation selectivity of TiO_(2)from azoxybenzene to nitrosobenzene,without using additives or changing solvent,while other metal or nonmetal doped TiO_(2)did not *** mechanistic investigations and DFT calculations unveil that Ti-O active site is responsible for triggering the aniline to form a new PhNOH intermediate,two PhNOH condense to azoxybenzene over TiO_(2)*** for Cu_(1)-TiO_(2),the charge-specific distribution between the isolated Cu and TiO_(2)generates unique Cu_(1)-O-Ti hybridization structure with nine catalytic active sites,eight of them make PhNOH take place spontaneous dissociation to produce *** work not only unveils a new mechanistic pathway featuring the PhNOH intermediate in aniline oxidation for the first time but also presents a novel approach for constructing single-atom doped metal oxides and exploring their intricate active sites.

关键词： Single atom doped metal oxide Aniline oxidation Selectivity New mechanism Active site

Constraints on the primordial curvature power spectrum by pulsar timing array data:a polynomial parameterization approach

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Communications in Theoretical Physics 2024年第1期76卷 96-104页

作者： qin Fei School of Mathematics and Physics Hubei Polytechnic UniversityHuangshi 435003China

The recent stochastic signal observed jointly by NANOGrav,parkes pulsar timing array,European pulsar timing array,and Chinese pulsar timing array can be accounted for by scalarinduced gravitational waves(SIGWs).The source of the SIGWs is from the primordial curvature perturbations,and the main contribution to the SIGWs is from the peak of the primordial curvature power *** effectively model this peak,we apply the Taylor expansion to parameterize *** the Taylor expansion parameterization,we apply Bayesian methods to constrain the primordial curvature power spectrum based on the NANOGrav 15 year data *** constraint on the primordial curvature power spectrum possesses a degree of generality,as the Taylor expansion can effectively approximate a wide range of function profiles.

关键词： pulsar timing array scalar-induced gravitational waves inflation

Five-view three-dimensional reconstructionfor ultrafast dynamic imaging of pulsedradiation sources

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Matter and Radiation at Extremes 2024年第2期9卷 63-73页

作者： Jianpeng Gao Liang Sheng Xinyi Wang Yanhong Zhang Liang Li baojun Duan Mei Zhang Yang Li Dongwei Hei Department of Engineering Physics Tsinghua UniversityBeijing 100084China National Key Laboratory of Intense Pulsed Radiation Simulation and Effect Northwest Institute of Nuclear TechnologyXi’an 710024China

Multiaxial neutron/x-ray imaging and three-dimensional (3D) reconstruction techniques play a crucial role in gaining valuable insights intothe generation and evolution mechanisms of pulsed radiation sources. Owing to the short emission time (∼200 ns) and drastic changes of thepulsed radiation source, it is necessary to acquire projection data within a few nanoseconds in order to achieve clear computed tomography3D imaging. As a consequence, projection data that can be used for computed tomography image reconstruction at a certain moment are oftenavailable for only a few angles. Traditional algorithms employed in the process of reconstructing 3D images with extremely incomplete datamay introduce significant distortions and artifacts into the final image. In this paper, we propose an iterative image reconstruction methodusing cylindrical harmonic decomposition and a self-supervised denoising network algorithm based on the deep image prior method. Weaugment the prior information with a 2D total variation prior and a 3D deep image prior. Single-wire Z-pinch imaging experiments have beencarried out at qin-1 facility in five views and four frames, with a time resolution of 3 ns for each frame and a time interval of 40 ns betweenadjacent frames. Both numerical simulations and experiments verify that our proposed algorithm can achieve high-quality reconstructionresults and obtain the 3D intensity distribution and evolution of extreme ultraviolet and soft x-ray emission from plasma.

关键词： frames image sources

Numerical study on the blocking effect of skin on Flash-Ball Impact and damage assessment

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Defence Technology（防务技术） 2024年第3期33卷 532-545页

作者： Dihua Ouyang Chunwei qin Xiaowen qin Qiantao Zhang Xingyu Liu Xi'an University of Architecture and Technology Xi'an 710055China Analysis and Testing Center Xi'an University of Architecture and TechnologyXi'an 710055China Engineering University of PAP Xi'an 710086China

To explore the response law of non-lethal large-size kinetic energy projectiles to blunt attack on skin tissue,and to evaluate the skin injury characteristics of the attacked personnel and the use safety of kinetic energy *** on the LS-DYNA simulation software,a three-layer skin simulation model and a Flash-Ball rubber bullet model are established,and the force-time and deformation-time biomechanical corridors of the Flash-Ball rubber bullet impacting human skin tissue are *** corridor curve and the energy transfer and diffusion are analyzed and *** safety evaluation of the damage caused by the rubber bullet shooting a human body at different distances is carried out using the empirical formula of the penetration ***,the safe shooting distance is *** results show that the model used in the simulation has a good correlation with the experimental data,its biomechanical corridor characteristics are different from those of conventional vehicle impact and smallsize projectile response *** energy transfer and action time of medium and low-speed impact may cause greater *** fat layer is the largest energy absorption *** minimum safe shooting distance to ensure skin tissue from penetrating damage is 15.8 m,and the limit specific kinetic energy of skin damage is 7.88 J/cm^(2).This study can be extended to the study of biomechanical response law and safety evaluation under the impact of the same type of large kinetic energy projectile,which provides an important theoretical reference for the police to use large kinetic energy projectiles to conduct safe shooting in peacekeeping operations.

关键词： KIPs Blunt strike Biomechanical response Damage analysis

三维碳负载镍掺杂对MgB_(2)微观结构和超导性能的影响

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功能材料 2022年第8期53卷 8009-8016页

作者：赵倩秦保军平学成龚闯闯天津科技大学机械工程学院天津市轻工与食品工程机械装备集成设计与在线监控重点实验室天津300222 天津市低碳绿色过程装备国际联合研究中心天津300222 天津大学材料科学与工程学院天津300354

寻找满意的第三组元并通过简单的化学掺杂获得高性能的MgB_(2)超导体,对推进MgB_(2)的实用化进程有着十分重要的意义。采用盐模板冻干法合成了三维碳(3DC)和三维碳负载镍(3DC/Ni)两种粉末,并通过原位掺杂的方式使用固相烧结法分别制备... 详细信息

寻找满意的第三组元并通过简单的化学掺杂获得高性能的MgB_(2)超导体,对推进MgB_(2)的实用化进程有着十分重要的意义。采用盐模板冻干法合成了三维碳(3DC)和三维碳负载镍(3DC/Ni)两种粉末,并通过原位掺杂的方式使用固相烧结法分别制备了含有这两种添加剂的MgB_(2)块材。借助X射线衍射技术及扫描电子显微镜对3DC掺杂MgB_(2)和3DC/Ni掺杂MgB_(2)的物相组成及微观形貌进行了表征,同时结合磁学测量系统探究了两种添加剂对MgB_(2)超导性能的影响。结果表明,3DC可以形成有效的碳掺杂提高MgB_(2)在高场下的载流性能;掺杂3DC/Ni后在Mg-Ni低温液相辅助烧结及3DC提供形核位点的协同作用下改善了MgB_(2)的晶粒连接性,同时也提高了MgB_(2)的磁通钉扎能力。采用冻干法合成的Ni颗粒在纳米尺度,解决了小尺寸掺杂易团聚的问题,但由于Ni为磁性粒子,使3DC/Ni掺杂MgB_(2)的临界电流密度(J_(c))没有明显提高。寻找一种更有效的金属纳米粒子是今后的尝试方向。

关键词：二硼化镁原位掺杂三维碳临界电流密度磁通钉扎

Limit state analysis of rigid retaining structures against seismically induced passive failure in heterogeneous soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1095-1105页

作者： Jianfeng Zhou Changbing qin College of Civil Engineering Huaqiao UniversityXiamen362021China School of Civil Engineering Chongqing UniversityChongqing400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityChongqing400045China National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas Chongqing UniversityChongqing400045China

Soils are not necessarily uniform and may present linearly varied or layered characteristics,for example the backfilled soils behind rigid retaining *** the presence of large lateral thrust imposed by arch bridge,passive soil failure is possible.A reliable prediction of passive earth pressure for the design of such wall is challenging in complicated soil strata,when adopting the conventional limit analysis *** order to overcome the challenge for generating a kinematically admissible velocity field and a statically allowable stress field,finite element method is incorporated into limit analysis,forming finiteelement upper-bound(FEUB)and finite-element lower-bound(FELB)***-static,original and modified pseudo-dynamic approaches are adopted to represent seismic acceleration *** generating feasible velocity and stress fields within discretized elements based on specific criteria,FEUB and FELB formulations of seismic passive earth pressure(coefficient K_(P))can be derived from work rate balance equation and stress *** to an interior point algorithm,optimal upper and lower bound solutions are *** proposed FEUB and FELB procedures are well validated by limit equilibrium as well as lower-bound and kinematic *** studies are carried out to investigate the effects of influential factors on seismic K_(P).Notably,true solution of K_(P) is well estimated based on less than 5%difference between FEUB and FELB solutions under such complex scenarios.

关键词： Retaining wall Passive earth pressure Earthquakes Finite-element limit-analysis methods

AI for Supporting the Freedom of Drawing

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Machine Intelligence Research 2024年第1期21卷 63-88页

作者： Xiaohua Sun Juexiao qin College of Design and Innovation Tongji UniversityShanghai 200082China

Artificial intelligence(AI)has recently been developing rapidly in image processing and *** is not only starting to take over repetitive and tedious tasks but is also involved in creative *** is one of the areas with the greatest potential for collaboration between humans and *** is an important approach to express various information,but due to the lack of appropriate knowledge and skills,ordinary people without long-time training are unable to draw *** there have been various attempts at human-AI collaboration in drawing,it is difficult for researchers to consider the wide variety of specific problems and develop univer-sal methods due to the openness,improvisation,and individuality of *** this paper,we first analysed the contents of drawing and the general creation process in ***,we have described a mechanism for using AI to enable people to regain the freedom of drawing ***,we have developed a framework that describes methods for analysing specific problems and quickly finding solutions by building connections between the influencing factors in drawing,the demands of humans,and possible implementa-tion *** framework also reveals a broad scope of possibilities for applying AI to support people in drawing.

关键词： Intention understanding drawing support drawing art human-artificial intelligence(AI)collaboration

The Coarse l^(p)-Novikov Conjecture and Banach Spaces with Property(H)

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Chinese Annals of Mathematics,Series B 2024年第2期45卷 193-220页

作者： Huan WANG qin WANG Research Center for Operator Algebras School of Mathematical SciencesEast China Normal UniversityShanghai 200241China Key Laboratory of MEA Ministry of Educationand Shanghai Key Laboratory of PMMPEast China Normal UniversityShanghai 200241China

In this paper,for 1

关键词： The coarse l^(p)-Novikov conjecture Banach spaces with Property(H) Coarse geometry K-Theory