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Nuclear Science and Techniques 2024年第1期35卷 155-169页

作者： si-Na Wei Zhao-Qing Feng School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China

The relativistic mean-field approach was implemented in the Lanzhou quantum molecular dynamics transport model(***). Using the ***, the properties of collective flow and pion production were investigated systematically for nuclear reactions with various isospin asymmetries. The directed and elliptic flows of the *** are able to describe the experimental data of STAR Collaboration. The directed flow difference between free neutrons and protons was associated with the stiffness of the symmetry energy, that is, a softer symmetry energy led to a larger flow difference. For various collision energies, the ratio between the π^(-) and π^(+) yields increased with a decrease in the slope parameter of the symmetry energy. When the collision energy was 270 MeV/nucleon, the single ratio of the pion transverse momentum spectra also increased with decreasing slope parameter of the symmetry energy in both nearly symmetric and neutron-rich ***, it is difficult to constrain the stiffness of the symmetry energy with the double ratio because of the lack of threshold energy correction on the pion production.

关键词： Heavy-ion collision Collective flow Pion production Symmetry energy Relativistic mean field

Unraveling Iterative Control Structures from Business Processes

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Journal of Computer Science & Technology 2021年第1期36卷 158-190页

作者： Yain-Whar si Weng-Hong Yung Department of Computer and Information Science University of MacaoMacaoChina

Iterative control structures allow the repeated execution of tasks,activities or sub-processes according to the given conditions in a process *** control structures can significantly increase the risk of triggering temporal exceptions since activities within the scope of these control structures could be repeatedly executed until a predefined condition is *** this paper,we propose two approaches to unravel iterative control structures from process *** first approach unravels loops based on zero-one *** second approach unravels loops based on branching probabilities assigned at split *** proposed methods can be used to unfold structured loops,nested loops and crossing *** the unfolded model does not contain any iterative control structures,it can be used for further analysis by process designers during the modeling *** proposed methods are implemented based on workflow graphs,and therefore they are compatible with modeling languages such as Business Process Modelling Notation(BPMN).In the experiments,the execution behavior of unfolded process models is compared against the original models based on the concept of *** results reveal that runs generated from the original models can be correctly executed in the unfolded BPMN models that do not contain any loops.

关键词： business process management iterative control structure unravelling zero-one principle branching probability

Stable 4.5 V LiCoO_(2)cathode material enabled by surface manganese oxides nanoshell

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Nano Research 2023年第2期16卷 2480-2485页

作者： Jun Wang si-Dong Zhang si-Jie Guo si-Qi Lu Yan-Song Xu Jin-Yang Li An-Min Cao Li-Jun Wan CAS Key Laboratory of Molecular Nanostructure and Nanotechnology and Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of Sciences(ICCAS)Beijing 100190China University of Chinese Academy of Sciences(UCAS) Beijing 100049China

Charging the LiCoO_(2)(LCO)cathode to a higher voltage,for example 4.5 V compared to the commonly used 4.2 V,is now intensively pursued so as to achieve a higher specific ***,it suffers severe surface structural degradation and detrimental interfacial side reactions between cathode and electrolyte,which lead to the fast capacity fading during long-term ***,a surface coating strategy was developed for the protection of 4.5 V LCO by constructing a manganese oxides(MOs)nanoshell around LCO particles,which was achieved through a solution-based coating process with success in controlling the growth kinetics of the coating *** found that the introduction of the MOs nanoshell is highly effective in alleviating the organic electrolyte decomposition at the cathode surface,thus ensuring a much more stable LiF-rich cathode-electrolyte interface and an obvious lower interfacial resistance during electrochemical ***,this protection layer can effectively improve the structural stability of the cathode by hindering the cracks formation and structural degradation of LCO ***,the MOs modified LCO exhibited excellent rate performance and a high discharge capacity retention of 81.5%after 100 cycles at 1 C compared with the untreated LCO(55.2%),as well as the improved thermal stability and cyclability at the elevated *** is expected that this discovery and fundamental understanding of the surface chemistry regulation strategy provide promising insights into improving the reversibility and stability of LCO cathode at the cut-off voltage of 4.5 V.

关键词： lithium-ion battery 4.5 V LiCoO_(2) manganese oxides surface coating interfacial stability regulation

Superconducting X-ray detectors

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Science China(Information Sciences) 2020年第8期63卷 91-109页

作者： Can YANG Mengting si Lixing YOU State Key Laboratory of Functional Materials for Informatics Shanghai Institute of Microsystem and Information Technology (SIMIT)Chinese Academy of Sciences CAS Center for Excellence in Superconducting Electronics (CENSE) Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Zhejiang Photon Technology Co.Ltd. Guigu Science Park

Owing to their high sensitivity and low noise, superconducting detectors are used for photon detection from microwave to high-energy particles. X-ray detection plays an important role in materials analysis, astronomy, and medical radiography, which require high efficiency as well as high energy resolution. However, traditional semiconducting detectors cannot fulfill these requirements. In this article, we review superconducting quantum detectors for X-ray detection, including transition-edge sensor(TES), superconducting tunneling junctions(STJs), kinetic inductance detectors(KIDs) and superconducting nanowire single-photon detectors(SNSPDs), and introduce the physical structures, working mechanisms, and device behaviors of these detectors. We also review their performances regarding X-ray detection and analyze their respective characteristics. According to recent progress and the requirements of various applications, possible improvement of superconducting detectors for X-rays are discussed.

关键词： superconducting X-ray detectors transition-edge sensors superconducting tunneling junctions kinetic inductance detectors superconducting nanowire single-photon detector

LaO_(x)(OH)_(y) supported platinum catalysts for CO oxidation:Deactivation by formation of lanthanum carbonate

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Journal of Rare Earths 2021年第3期39卷 297-304,I0003页

作者： Luozhen Jiang Junxiang Chen Rui si Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China Shanghai Synchrotron Radiation Facility Zhangjiang LaboratoryShanghai 201204China Division of China TILON Group Technology LimitedShanghai 200090China University of Chinese Academy of Sciences Beijing 100049China

Platinum catalyst for CO oxidation has been studied for decades,due to its high activity and good *** this work,we prepared three different lantha num oxide or hydroxide supports(LaO_(x)(OH)_(y)),and deposited platinum(Pt) with 0.5 at% via an impregnation approach to synthesize Pt/LaO_(x)(OH)_(y) ***,we find that these catalysts perform a poor stability for the CO oxidation *** fresh and used samples were comprehensively characterized by multiple techniques including power X-ray diffraction(XRD),X-ray absorption fine structure(XAFS),transmission electron microscopy(TEM),temperature-programmed reduction by carbon monoxide(CO-TPR) and thermogravimetric analysis(TGA),to demonstrate that the oxidized platinum atoms or clusters,without any component of Pt-Pt metallic bond,are highly dispersed on the surface of LaO_(x)(OH)_(y).Furthermore,the as-formed lanthanum carbonate(La_(2)O_(2)CO_(3)) during the exposure to ambient circumstances or in the reaction atmosphere of CO+O_(2),severely impair the reactivity of Pt/LaO_(x)(OH)_(y).On the basis of the obtained experimental results,we have drawn a conclusion that the oxidized P_(t)O_(x) atoms or PtxOy clusters are the active species for CO oxidation,while the formation of lanthanum carbonate is the origin of deactivation on reactivity.

关键词： Platinum catalyst Lanthanum oxide Lanthanum hydroxide CO oxidation Structure-activity relationship Rare earths

Determination method of mesh size for numerical simulation of blast load in near-ground detonation

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Defence Technology（防务技术） 2024年第8期38卷 111-125页

作者： Doudou si Zuanfeng Pan Haipeng Zhang College of Civil Engineering Tongji UniversityShanghai 200092China State Key Lab of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China

In order to improve the overall resilience of the urban infrastructures, it is required to conduct blast resistant design for important building structures in the city. For complex terrain in the city, it is recommended to determine the blast load on the structures via numerical simulation. since the mesh size of the numerical model highly depends on the explosion scenario, there is no generally applicable approach for the mesh size selection. An efficient method to determine the mesh size of the numerical model of near-ground detonation based on explosion scenarios is proposed in this study. The effect of mesh size on the propagation of blast wave under different explosive weights was studied, and the correlations between the mesh size effect and the charge weight or the scaled distance was described. Based on the principle of the finite element method and Hopkinson-Cranz scaling law, a mesh size measurement unit related to the explosive weight was proposed as the criterion for determining the mesh size in the numerical simulation. Finally, the applicability of the method proposed in this paper was verified by comparing the results from numerical simulation and the explosion tests and was verified in AUTODYN.

关键词： Blast load Mesh size effect Numerical simulation Scaled mesh size Verification

STRESS INTENsiTY FACTORS CALCULATION IN ANTI-PLANE FRACTURE PROBLEM BY ORTHOGONAL INTEGRAL EXTRACTION METHOD BASED ON FEMOL

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Acta Mechanica Solida sinica 2007年第1期20卷 87-94页

作者： Xu Yongjun Yuau si Institute of Mechanics Chinese Academy of Sciences Beifing 100080 China Department of Civil Engineering Tsinghua University Beijing 100084 China

For an anti-plane problem, the differential operator is self-adjoint and the corresponding eigenfunctions belong to the Hilbert space. The orthogonal property between eigenfunctions （or between the derivatives of eigenfunctions） of anti-plane problem is exploited. We developed for the first time two sets of radius-independent orthogonal integrals for extraction of stress intensity factors （siFs）, so any order siF can be extracted based on a certain known solution of displacement （an analytic result or a numerical result）. Many numerical examples based on the finite element method of lines （FEMOL） show that the present method is very powerful and efficient.

关键词： anti-plane problem Hilbert space eigenvalue eigenfunction orthogonal relationship stress intensity factor finite element method of lines

Gastric Adenocarcinoma Treatment in Africa: Surgery Alone or Perioperative Chemotherapy?

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Journal of Cancer Therapy 2017年第7期8卷 653-662页

作者： Nayi Zongo Bagué Abdoul Halim Ouangré Edgar Bagré sidpawalmde Carine Zida Maurice Boukoungou Gilbert Sanou Adama Lompo Olga Mélanie traoré si simon Ahmadou Dem General and Digestive Surgery Yalgado Ouédraogo University Hospital Ouagadougou Burkina Faso Oncology Institute Joliot Curie of Dakar Dakar Senegal General and Digestive Surgery Department University Hospital Center Blaise COMPAORE Ouagadougou Burkina Faso Pathological Anatomy and Forensic Unit Yalgado Ouédraogo University Hospital Ouagadougou Burkina Faso

Aim: Evaluate the impact of MAGIC trial on gastric adenocarcinoma’s management in Africa. Method and methodology: It was about a review of literature on therapeutic aspects of gastric adenocarcinoma in the African area. We have taken a census of 21 articles including 2792 patients published between 1980 and 2013. We have distinguished articles published before 2006 (group 1) from those published after 2006 (group 2) to better understand therapeutic changes after that perioperative chemotherapy has become a standard in gastric adenocarcinoma’s management. Results: Surgery remains in Africa the first and practically the only treatment weapon in gastric adenocarcinoma: 46% to 92% people in the 1st group and 65% to 100% people in the 2nd group underwent surgical procedures. Perioperative chemotherapy takes longer to be part of therapeutic habits (0.18%). Factors related to patients such alteration of general state with a WHO performance status superior to 2 in 72% of cases, the lack of financial accessibility to anticancerous drugs explains partly the non-use of perioperative chemotherapy. This is also due to factors peculiar to our sanitation structures which don’t have enough cancer specialists. So we noticed that MAGIC trial is simply ignored in certain studies. The lack of adoption of perioperative chemotherapy explains with delayed diagnosis the low survival of patients in the African area. Conclusion: MAGIC trial practically has no effect on therapeutic behavior yet comparatively to gastric adenocarcinoma in Africa. The insurance particularly relies on surgery only until now. However, it might enable us to improve gastric adenocarcinoma’s survival rates.

关键词： Adenocarcinoma Stomach Surgery Perioperative Chemotherapy Africa

simplified Numerical Models of the Unsteady Tip Leakage Flow in Compressor

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Journal of Thermal Science 2023年第6期32卷 2386-2399页

作者： si Changxin WU Zihao LIU Xiaohua School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai200240China China Three Gorges Investment Management Co. Ltd.Shanghai200124China Key Laboratory of Aerodynamic Noise Control China Aerodynamics Research and Development CenterMianyang621000China

Tip leakage flow(TLF)in compressors,which can cause flow blockage in blade passage and induce efficiency loss,is also a potential threat to the unsteady flow stability of modern *** paper provides an overview of the significance of tip leakage flow research,and introduces relevant previous *** calculating by different methods,large eddy simulation(LES)is demonstrated again as a suitable compromise between accuracy and computational cost for the unsteady flow *** types of simplified tip leakage flow models using LES are adopted with a focus on the unsteady characteristics of shedding vortices in a cavity *** paper applies these models to study the unsteady tip leakage flow which triggers the onset of acoustic resonance in a multistage axial *** with the detected acoustic resonance frequency of 5.22 rotational frequency(RF)in the previous experiment,the computed combination frequency in the 2-D model is equal to 5.232RF,and the simplified 3-D unsteady tip leakage flow model results in a combination frequency of ***,based on the small relative error between model results and experimental results,the simplified numerical models are validated to be sufficiently accurate,and theoretically provide a useful basis for the subsequent research of unsteady tip leakage flow in turbomachinery.

关键词： turbomachinery compressor tip leakage flow unsteady flow

Structural Manipulation of Aminal-crosslinked Polybutadiene for Recyclable and Healable Elastomers

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Chinese Journal of Polymer Science 2021年第10期39卷 1337-1344,I0008页

作者： Zheng-Hai Tang Hui Zeng si-Qi Wei si-Wu Wu Bao-Chun Guo Department of Polymer Materials and Engineering South China University of TechnologyGuangzhou 510640China

Recently,increasingly growing efforts have been devoted to incorporating dynamic covalent bonds into covalently crosslinked networks to address the persistent trade-offs between chemical crosslinking and ***,a series of dynamic aminal bond crosslinked polybutadiene rubbers(PAPB)are prepared by crosslinking aldehyde group-terminated polybutadiene rubber(APB)with *** varying the molecular weight of APB,the crosslinking density of PAPB is changed,which offers the platform to regulate the mechanical characteristics and dynamic ***,with the decrease of APB molecular weight,*** the increase of crosslinking density,the modulus of PAPB gradually increases while the elongation at break conversely decreases,and the activation energy for network rearrangement initially decreases and then *** resultant PAPB exhibit vitrimer-like behaviors that can alter the network topologies at elevated temperatures without the loss of structural integrity through dissociative aminal exchange reactions,while the protic source can accelerate aminal dissociation and result in network dissolution even at room *** to the aminal exchange,PAPB are thermally malleable and can almost restore the original mechanical characteristics after recycling;besides,they are capable of healing at a relatively low crosslinking density.

关键词： Aminal Recyclability Healing Structural manipulation Dynamic covalent network