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An experimental review of open heavy flavor and quarkonium production at RHIC

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Nuclear Science and Techniques 2020年第8期31卷 72-103页

作者： Ze-Bo tang Wang-Mei Zha Yi-Fei Zhang State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China

Open heavy flavors and quarkonia are unique probes of the hot–dense medium produced in heavy-ion collisions. Their production in p+p collisions also constitutes an important test of QCD. In this paper, we review selected results on the open heavy flavors and quarkonia generated in the p+p and heavy-ion collisions at the Relativistic Heavy Ion Collider. The physical implications are also discussed.

关键词： Heavy flavor Heavy quark Quarkonium Quark–gluon plasma Heavy-ion collisions QCD

Scheme for generating 1 nm X-ray beams carrying orbital angular momentum at the SXFEL

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Nuclear Science and Techniques 2020年第9期31卷 33-44页

作者： He-Ping Geng Jian-Hui Chen Zhen-tang Zhao Chinese Academy of Sciences Shanghai Institute of Applied PhysicsShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Chinese Academy of Sciences Shanghai Advanced Research InstituteShanghai 201210China

Optical vortices have the main features of helical wavefronts and spiral phase structures,and carry orbital angular *** special structure of visible light has been produced and studied for various *** notable characteristics of photons were also tested in the extreme-ultraviolet and X-ray *** this article,we simulate the use of a simple afterburner configuration by directly adding helical undulators after the SASE undulators with the Shanghai Soft X-ray FEL to generate high intensity X-ray vortices with wavelengths^1 *** to other methods,this approach is easier to implement,cost-effective,and more efficient.

关键词： X-ray Orbital angular momentum(OAM) Synchrotron light source Free-electron laser(FEL)

High-velocity impact responses of 2618 aluminum plates for engine containment systems under combined actions of projectile form and oblique angle

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Chinese Journal of Aeronautics 2019年第6期32卷 1428-1441页

作者： Cunxian WANG Tao SUO Yulong LI Pu XUE Zhongbin tang School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of Impact Dynamics and Engineering Application(IDEA) Northwestern Polytechnical UniversityXi’an 710072China Fundamental Science on Aircraft Structural Mechanics and Strength Laboratory Northwestern Polytechnical UniversityXi’an 710072China

Ballistic impact tests were carried out with examined projectiles of the Ti-6Al-4V titanium alloy to investigate the impact response of the 2618 aluminum plates at a nominal velocity of 210 m/s. The influence of projectile forms and oblique angles on damage formation was particularly discussed by applying different loading conditions such as multiple projectile forms and oblique angles. Additionally, the numerical simulation method was employed to provide further insight into the characteristics of damage and target responses. The Johnson-Cook(J-C)constitutive model with revised failure parameters was used to support the simulations to assess target responses and characteristics of the damage created from different impact conditions. Results show that there is a significant transition in the deformation mode as changes of the projectile form are applied. Moreover, the cracks on the back of the 2618 aluminum alloy plates impacted by the solid plate projectile and the hollow blade projectile tend to locate at different positions, which are supposed to be influenced by local bending and stretching. The work in this paper may provide guidance for the design of fan blade containment systems.

关键词： 2618 aluminum plate Damage characteristic High-velocity impact Johnson-Cook(J-C) Projectile forms

Biochar-mediated regulation of greenhouse gas emission and toxicity reduction in bioremediation of organophosphorus pesticide-contaminated soils

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Chinese Journal of Chemical Engineering 2018年第12期26卷 2592-2600页

作者： Meinan Zhen Benru Song Xiaomei Liu Radhika Chandankere Jingchun tang Key Laboratory of Pollution Processes and Environmental Criteria (Ministry of Education) Tianjin Engineering Center of Environmental Diagnosis and Contamination Remediation College of Environmental Science and Engineering Nankai University Department of Building Civil and Environmental Engineering Concordia University

Organophosphorus pesticides(OPPs) are a set of toxic persistent organic pollutants(POPs) present in the environment. Recently, biochar-mediated bioremediation has exhibited many advantages over conventional methods for the remediation of pesticide-contaminated soil. In the present study, biochar and nitrogen fertilizer(NH_4NO_3)were employed to remediate OPP-contaminated soil and the greenhouse gas(GHG) emission during 90 days of incubation was investigated. After thermal desorption treatment, the content of organophosphorus pesticides reduced from 175.61 μg·kg^(-1) to 62.68 μg·kg^(-1). The addition of NH_4NO_3 in the following bioremediation led to larger reduction(34.35%) of the pesticide concentration than that of biochar(31.90%) for the contaminated soils with thermal desorption treatment, while the simultaneous addition of biochar and NH_4NO_3 led to the largest reduction of pesticide concentration(11.07%) for the soil without thermal desorption treatment. The addition of biochar and NH_4NO_3 only slightly increased the emission rate of GHGs from the soil without thermal treatment,but remarkably increased the emission rate of GHGs from the soil after thermal treatment. In most cases, the addition of NH_4NO_3 is more effective than biochar to promote the degradation of pesticide, but also exhibited higher GHG emission. The microbial community analysis suggests that the enhanced degradation of pesticide is mainly owing to the increased activity of microorganism.

关键词： Organophosphorus pesticides Biochar NH3NO4 Remediation Greenhouse gas Microbial community

Shake table test of soil-pile groups-bridge structure interaction in liquefiable ground

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Earthquake Engineering and Engineering Vibration 2010年第1期9卷 39-50页

作者： tang Liang ling Xianzhang Xu Pengju Gao Xia Wang dongsheng School of Civil Engineering Harbin institute of Technology Harbin 150090 China Research Centre of Road and Bridge Engineering Dalian Maritime University Dalian 116026 China

This paper describes a shake table test study on the seismic response of low-cap pile groups and a bridge structure in liquefiable ground. The soil profile, contained in a large-scale laminar shear box, consisted of a horizontally saturated sand layer overlaid with a silty clay layer, with the simulated low-cap pile groups embedded. The container was excited in three E1 Centro earthquake events of different levels. Test results indicate that excessive pore pressure （EPP） during slight shaking only slightly accumulated, and the accumulation mainly occurred during strong shaking. The EPP was gradually enhanced as the amplitude and duration of the input acceleration increased. The acceleration response of the sand was remarkably influenced by soil liquefaction. As soil liquefaction occurred, the peak sand displacement gradually lagged behind the input acceleration; meanwhile, the sand displacement exhibited an increasing effect on the bending moment of the pile, and acceleration responses of the pile and the sand layer gradually changed from decreasing to increasing in the vertical direction from the bottom to the top. A jump variation of the bending moment on the pile was observed near the soil interface in all three input earthquake events. It is thought that the shake table tests could provide the groundwork for further seismic performance studies of low-cap pile groups used in bridges located on liquefiable groun.

关键词： liquefiable ground seismic soil-pile-structure interaction pile groups of bridge shake table test

Nanoscale Tapered Pt Bottom Electrode Fabricated by FIB for Low Power and Highly Stable Operations of Phase Change Memory

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Chinese Physics Letters 2010年第2期27卷 295-298页

作者：吕士龙宋志棠刘燕封松林 State Key Laboratory of Functional Materials for Informatics Laboratory of Nanotechnology Shanghai Institute of Micro-system and Information Technology Chinese Academy of Sciences Shanghai 200050 Graduate School of the Chinese Academy of Sciences Beijing 100049

Phase change random access memory （PC-RAM） based on Si2Sb2Te5 with a Pt tapered heating electrode （Pt-THE）, which is fabricated using a focus ion beam （FIB）, is investigated. Compared with the tungsten electrode, the Pt-THE facilitates the temperature rise in phase change material, which causes the decrease of reset voltage from 3.6 to 2.7 V. The programming region of the cell with the Pt-THE is smaller than that of the cell with a cylindrical tungsten heating electrode. The improved performance of the PC-RAM with a Pt-THE is attributed to the higher resistivity and lower thermal conductivity of the Pt electrode, and the reduction of the programming region, which is also verified by thermal simulation.

关键词： Condensed matter: electrical magnetic and optical Electronics and devices Semiconductors Nanoscale science and low-D systems

Adding regular expressions to graph reachability and pattern queries

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Frontiers of Computer Science 2012年第3期6卷 313-338页

作者： Wenfei FAN Jianzhong LI Shuai MA Nan tang Yinghui WU School of Informatics University of EdinburghEdinburgh EH89YLUK Department of Computer Science and Engineering Harbin Institute of TechnologyHarbin 150001China NLSDE Lab Beihang UniversityBeijing 100919China Qatar Computing Research Institute Qatar FoundationDohaQatar

It is increasingly common to find graphs in which edges are of different types, indicating a variety of relation- ships. For such graphs we propose a class of reachability queries and a class of graph patterns, in which an edge is specified with a regular expression of a certain form, ex- pressing the connectivity of a data graph via edges of var- ious types. In addition, we define graph pattern matching based on a revised notion of graph simulation. On graphs in emerging applications such as social networks, we show that these queries are capable of finding more sensible informa- tion than their traditional counterparts. Better still, their in- creased expressive power does not come with extra complex- ity. Indeed, （1） we investigate their containment and mini- mization problems, and show that these fundamental prob- lems are in quadratic time for reachability queries and are in cubic time for pattern queries. （2） We develop an algorithm for answering reachability queries, in quadratic time as for their traditional counterpart. （3） We provide two cubic-time algorithms for evaluating graph pattern queries, as opposed to the NP-completeness of graph pattern matching via subgraph isomorphism. （4） The effectiveness and efficiency of these al- gorithms are experimentally verified using real-life data and synthetic data.

关键词： graph reachability graph pattern queries regu-lar expressions containment equivalence minimization

Drilling Power Consumption and Soil Conveying Volume Performances of Lunar Sampling Auger

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Chinese Journal of Mechanical Engineering 2015年第3期28卷 451-459页

作者： TIAN Ye tang Dewei DENG Zongquan JIANG Shengyuan QUAN Qiquan State Key Laboratory of Robotics and System Harbin Institute of Technology University Research Center of Package Mechanical Design Harbin University of Commerce

The sampling auger used in lunar sampling and return mission is to transmit power and convey soil, and its performance is the key factor of the whole mission. However, there is currently a lack of the optimization research on soil conveying volume and power consumption models in auger structure design. To provide the drilled object, the simulation lunar soil, whose physical and mechanical property is the same as the real soil, is made by reducing soil void ratio. The models are formulated to analyze the influence of auger structure parameters on power consumption and soil conveying volume. To obtain the optimized structure parameters of auger, the multi-objective optimization functions of the maximum soil conveying volume and minimum power consumption are developed. To verify the correctness of the models, the performances of different augers drilling simulation soil are tested. The test results demonstrate that the power consumption of optimized auger is the lowest both in theory and test, and the experimental results of soil conveying volume are in agreement with theoretical analysis. Consequently, a new method for designing a lunar sampling auger is proposed which includes the models of soil conveying volume and transportation power consumption, the optimization of structure parameters and the comparison tests. This method provides a reference for sampling auger designing of the Chinese Lunar Sample Mission.

关键词： lunar sampling optimal design auger soil conveying volume model structure parameter

Perchlorate removal using granular activated carbon supported iron compounds: Synthesis, characterization and reactivity

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Journal of Environmental Sciences 2010年第11期22卷 1807-1813页

作者： Jianhong Xu Naiyun Gao Yulin tang Yang Deng Minhao Sui State Key Laboratory of Pollution Control and Resource Resue Tongji University Shanghai 200092 China Jiangxi University of Science and Technology Ganzhou 341000 China Department of Earth and Environmental Studies Montclair State University Montclair New Jersey 07043 USA

Synthesis and use of the iron compounds supported on granular activated carbon （ICs/GAC） have shown significant environmental implications for perchlorate （ClO4^- ） removal. ICs/GAC was synthesized via hydrolyzing FeSO 4 ·7H2O on GAC, reduced by NaBH 4 solution in polyethylene glycol 6000 and ethanol solution, dried in vacuum condition and exposed to air. Synthesized ICs/GAC was characterized using transmission electron micrograph （TEM）, Brunauer-Emmett-Teller, X-ray photoelectron spectroscopy （XPS）. ICs/GAC was determined to be containing a large amount of FeOHSO 4 , Fe2O3 and a small amount of zero-valent iron （ZVI） nanoparticles according to TEM and XPS measurements. Batch static kinetic tests showed that 97% of ClO4^- was removed within 10 hr at 90°C and 86% of ClO4^- was removed within 12 hr at 25°C, at ICs/GAC dosage of 20 g/L. The experimental results also showed that FeOHSO 4 and Fe 2 O 3 nanoparticles have the function of perchlorate adsorption and play important roles in ClO4^- removal. The activation energy （E a ） was determined to be 9.56 kJ/mol.

关键词： perchlorate removal ICs /GAC activation energy synthesis