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Fe_(n)Co_(55-n)与Co_(n)Mo_(55-n)(n=0~55)团簇基态的能量与结构演化

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原子与分子物理学报 2025年第5期42卷 57-66页

作者：程彪郑琪琪陈轩段海明新疆大学物理科学与技术学院乌鲁木齐830049

采用半经验的Gupta多体势函数结合遗传算法及分子动力学淬火算法,系统研究了Co_(n)Mo_(55-n)(n=0~55)与Fe_(n)Co_(55-n)(n=0~55)团簇的基态结构与能量.通过分析基态结构的相似函数、质心间距、平均键长、平均原子配位数、平均结合能、... 详细信息

采用半经验的Gupta多体势函数结合遗传算法及分子动力学淬火算法,系统研究了Co_(n)Mo_(55-n)(n=0~55)与Fe_(n)Co_(55-n)(n=0~55)团簇的基态结构与能量.通过分析基态结构的相似函数、质心间距、平均键长、平均原子配位数、平均结合能、混合能与二阶差分能.探究了团簇基态的结构特征及稳定性与团簇所含元素种类及组分的关联.结果表明:对Co-Mo混合团簇,随Co原子数目增加,Co原子依次占据团簇中心与最外层顶点,混合团簇逐渐出现组分偏析与无序现象;对Fe-Co混合团簇,基态结构主体上均体现为围绕Mackay二十面体构型的结构畸变,随Fe原子含量增加,Fe原子先占据团簇外表面顶点位置直到全部包裹Co原子,逐渐形成核壳式结构;Co_(13)Mo_(42)与Fe_(42)Co_(13)是幻数结构团簇,研究发现组分效应导致的团簇高对称性相比团簇平均键长与平均原子配位数更能解释幻数结构的成因.

关键词：遗传算法淬火算法双金属团簇基态结构

Tumor heterogeneity and the potential role of liquid biopsy in bladder cancer

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Cancer Communications 2021年第2期41卷 91-108页

作者： hai-ming Huang hai-Xia Li Department of Clinical Laboratory Peking University First HospitalBeijing 100034P.R.China

Bladder cancer(BC)is a heterogeneous disease that characterized by genomic instability and a high mutation *** in tumor may partially explain the diversity of responses to targeted therapies and the various clinical outcomes.A combination of cytology and cystoscopy is the standard methodology for BC diagnosis,prognosis,and disease ***,genomics analyses of single tumor-biopsy specimens may underestimate the mutational burden of heterogeneous *** biopsy,as a promising technology,enables analysis of tumor components in the bodily fluids,such as blood and urine,at multiple time points and provides a minimally invasive approach that can track the evolutionary dynamics and monitor tumor *** this review,we describe the multiple faces of BC heterogeneity at the genomic and transcriptional levels and how they affect clinical care and *** also summarize the outcomes of liquid biopsy in BC,which plays a potential role in revealing tumor ***,we discuss the challenges that must be addressed before liquid biopsy can be widely used in clinical treatment.

关键词： bladder cancer genomic heterogeneity transcriptome heterogeneity liquid biopsy circulating tumor DNA

A Light-Weight Opportunistic Forwarding Protocol with Optimized Preamble Length for Low-Duty-Cycle Wireless Sensor Networks

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Journal of Computer Science & Technology 2017年第1期32卷 168-180页

作者： hai-ming Chen Li Cui Gang Zhou Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China Department of Computer Science College of William and Mary Williamsburg VA 23185 U.S.A.

In wireless sensor networks, sensed information is expected to be reliably and timely delivered to a sink in an ad-hoc way. However, it is challenging to achieve this goal because of the highly dynamic topology induced from asynchronous duty cycles and temporally and spatially varying link quality among nodes. Currently some opportunistic forwarding protocols have been proposed to address the challenge. However, they involve complicated mechanisms to determine the best forwarder at each hop, which incurs heavy overheads for the resource-constrained nodes. In this paper, we propose a light-weight opportunistic forwarding （LWOF） scheme. Different from other recently proposed opportunistic forwarding schemes, LWOF employs neither historical network information nor a contention process to select a forwarder prior to data transmissions. It confines forwarding candidates to an optimized area, and takes advantage of the preamble in low-power-listening （LPL） MAC protocols and dual-channel communication to forward a packet to a unique downstream node towards the sink with a high probability, without making a forwarding decision prior to data transmission. Under LWOF, we optimize LPL MAC protocol to have a shortened preamble （LWMAC）, based on a theoretical analysis on the relationship among preamble length, delivery probability at each hop, node density and sleep duration. Simulation results show that LWOF, along with LWMAC, can achieve relatively good performance in terms of delivery reliability and latency, as a receiver-based opportunistic forwarding protocol, while reducing energy consumption per packet by at least twice.

关键词： wireless sensor network low duty cycle low power listening opportunistic forwarding

Laser-Manipulating Macroscopic Quantum States of a Bose-Einstein Condensate Held in a Kronig-Penny Potential

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Communications in Theoretical Physics 2009年第7期52卷 68-74页

作者： ZHU Qian-Quan hai Wen-Hua DENG hai-ming Department of Physics Hunan Normal University Changsha 410081 China

We investigate the boundary vaJue problem （BVP） of a quasi-one-dimensional Gross-Pitaevskii equation with the Kronig-Penney potential （KPP） of period d, which governs a repulsive Bose-Einstein condensate. Under the zero and periodic boundary conditions, we show how to determine n exact stationary eigenstates {Rn} corresponding to different chemical potentials {μn} from the known solutions of the system. The n-th eigenstate P~ is the Jacobian elliptic function with period 2din for n = 1,2,…, and with zero points containing the potential barrier positions. So Rn is differentiable at any spatial point and R2 describes n complete wave-packets in each period of the KPP. It is revealed that one can use a laser pulse modeled by a 5 potential at site xi to manipulate the transitions from the states of {Rn} with zero Point x≠xi to the states of {Rn＇} with zero Point x= Xi. The results suggest an experimental scheme for applying BEC to test the BVP and to observe the macroscopic quantum transitions.

关键词： Bose-Einstein Condenstate Kronig-Penney potential boundary value problem laser-manipulating macroscopic quantum state

Advances in magnetic nanoparticle-based magnetic resonance imaging contrast agents

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Nano Research 2023年第11期16卷 12531-12542页

作者： Huan Zhang Xiao Li Liu hai ming Fan Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education College of Chemistry and Materials ScienceNorthwest UniversityXi’an 710127China Department of Radiology Zhuhai People’s Hospital(Zhuhai Hospital Affiliated with Jinan University)Zhuhai 519000China Laboratory of Resource Biology and Biotechnology in Western China Ministry of EducationProvincial Key Laboratory of Biotechnology of Shaanxi ProvinceNorthwest UniversityXi’an 710069China Institute of Regenerative and Reconstructive Medicine Med-X InstituteFirst Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710049China National Local Joint Engineering Research Center for Precision Surgery&Regenerative Medicine Shaanxi Provincial Center for Regenerative Medicine and Surgical EngineeringFirst Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061China

Magnetic resonance imaging(MRI)has revolutionized medical imaging diagnostics with the advantages of non-invasive nature,absence of ionizing radiation,unrestricted penetration depth,high-resolution imaging of soft tissues,organs and blood vessels,and multi-parameter and multi-sequence *** agents(CAs)are crucial for enhancing image quality,detecting molecular-level changes,and providing comprehensive diagnostic information in contrast enhanced ***,the performance of clinical Gd-based CAs represents a limitation to the improvement of MRI sensitivity,specificity,and versatility,thereby impeding the achievement of satisfactory imaging *** recent years,the development of magnetic nanoparticle-based CAs has emerged as a promising avenue to enhance the capabilities of ***,we review the advances in magnetic nanoparticle-based MRI CAs,including blood pool CAs,biochemically-targeted CAs,stimulus-responsive CAs,and ultra-high field MRI CAs,as well as the use of CAs for cell labeling and ***,we offer insights into the future prospects and challenges associated with the integration of these nanoparticles into clinical practice.

关键词： magnetic resonance imaging magnetic nanoparticle blood pool contrast agents biochemically-targeted contrast agents stimulus-responsive contrast agents

Airborne transmission during short-term events: Direct route over indirect route

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Building Simulation 2022年第12期15卷 2097-2110页

作者： Xiujie Li Zhengtao Ai Jinjun Ye Cheuk ming Mak hai ming Wong Department of Building Environment and Energy Engineering The Hong Kong Polytechnic UniversityHong KongChina Department of Civil Engineering Hunan UniversityChangshaChina National Center for International Research Collaboration in Building Safety and Environment Hunan UniversityChangshaChina Faculty of Dentistry The University of Hong KongHong KongChina

Numerous short-term exposure events in public spaces were reported during the COVID-19 pandemic,especially during the spread of Delta and ***,the currently used exposure risk assessment models and mitigation measures are mostly based on the assumption of steady-state and complete-mixing *** present study investigates the dynamics of airborne transmission in short-term events when a steady state is not reached before the end of the ***-eddy simulation(LES)is performed to predict the airborne transmission in short-term events,and three representative physical distances between two occupants are *** time-averaged and phase-averaged exposure indices are used to evaluate the exposure *** results present that the exposure index in the short-term events constantly varies over time,especially within the first 1/ACH(air changes per hour)hour of exposure between occupants in close proximity,posing high uncertainty to the spatial and temporal evolutions of the risk of *** decoupling analysis of the direct and indirect airborne transmission routes indicates that the direct airborne transmission is the predominated route in short-term *** suggests also that the general dilution ventilation has a relatively limited efficiency in mitigating the risk of direct airborne transmission,but determines largely the occurrence time of the indirect *** the randomness,discreteness,localization,and high-risk characteristics of direct airborne transmission,a localized method that has a direct interference on the respiratory flows would be better than dilution ventilation for short-term events,in terms of both efficiency and cost.

关键词： airborne transmission short-term events direct exposure transient computational fluid dynamics(CFD) exposure risk

Development and accuracy of artificial intelligence-generated prediction of facial changes in orthodontic treatment:a scoping review

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2023年第11期24卷 974-984页

作者： Jiajun ZHU Yuxin YANG hai ming WONG Stomatology Hospital School of StomatologyZhejiang University School of MedicineZhejiang Provincial Clinical Research Center for Oral DiseasesKey Laboratory of Oral Biomedical Research of Zhejiang ProvinceCancer Center of Zhejiang UniversityEngineering Research Center of Oral Biomaterials and Devices of Zhejiang ProvinceHangzhou310000China Faculty of Dentistry The University of Hong KongHong KongChina

Artificial intelligence(AI)has been utilized in soft-tissue analysis and prediction in orthodontic treatment planning,although its reliability has not been systematically *** scoping review was conducted to outline the development of AI in terms of predicting soft-tissue changes after orthodontic treatment,as well as to comprehensively evaluate its prediction *** electronic databases(PubMed,EBSCOhost,Web of Science,Embase,Cochrane Library,and Scopus)were searched up to March 14,*** studies investigating the performance of AI-based systems in predicting post-orthodontic soft-tissue alterations were *** Quality Assessment of Diagnostic Accuracy Studies-2(QUADAS-2)and Joanna Briggs Institute(JBI)appraisal checklist for diagnostic test accuracy studies were applied to assess risk of bias,while the Grading of Recommendation,Assessment,Development,and Evaluation(GRADE)assessment was conducted to evaluate the certainty of *** screening 2500 studies,four non-randomized clinical trials were finally included for full-text *** found a low level of evidence indicating an estimated high overall accuracy of AI-generated prediction,whereas the lower lip and chin seemed to be the least predictable ***,the facial morphology simulated by AI via the fusion of multimodality images was considered to be reasonably *** all of the included studies that were not randomized clinical trials(non-RCTs)showed a moderate to high risk of bias,more well-designed clinical trials with sufficient sample size are needed in future work.

关键词： Facial morphology Soft-tissue changes Artificial intelligence(AI) Orthodontic treatment

Sparse Modal Decomposition Method Addressing Underdetermined Vortex-Induced Vibration Reconstruction Problem for Marine Risers

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China Ocean Engineering 2024年第2期38卷 285-296页

作者： DU Zun-feng ZHU hai-ming YU Jian-xing State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation School of Civil EngineeringTianjin UniversityTianjin 300350China

When investigating the vortex-induced vibration(VIV)of marine risers,extrapolating the dynamic response on the entire length based on limited sensor measurements is a crucial step in both laboratory experiments and fatigue monitoring of real *** problem is conventionally solved using the modal decomposition method,based on the principle that the response can be approximated by a weighted sum of limited vibration ***,the method is not valid when the problem is underdetermined,i.e.,the number of unknown mode weights is more than the number of known *** study proposed a sparse modal decomposition method based on the compressed sensing theory and the Compressive Sampling Matching Pursuit(Co Sa MP)algorithm,exploiting the sparsity of VIV in the modal *** the validation study based on high-order VIV experiment data,the proposed method successfully reconstructed the response using only seven acceleration measurements when the conventional methods failed.A primary advantage of the proposed method is that it offers a completely data-driven approach for the underdetermined VIV reconstruction problem,which is more favorable than existing model-dependent solutions for many practical applications such as riser structural health monitoring.

关键词： motion reconstruction vortex-induced vibration(VIV) marine riser modal decomposition method compressed sensing

Material removal mechanisms and characteristics of potassium dihydrogen phosphate crystals under nanoscratching

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Advances in Manufacturing 2021年第4期9卷 558-567页

作者： Ning Hou Yong Zhang Liang-Chi Zhang ming-hai Wang School of Mechatronics Engineering Shenyang Aerospace UniversityShenyang 110136People’s Republic of China Key Laboratory of Fundamental Science for National Defense of Aeronautical Digital Manufacturing Process Shenyang Aerospace UniversityShenyang 110136People’s Republic of China School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001People’s Republic of China Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhen 518055GuangdongPeople’s Republic of China

Potassium dihydrogen phosphate(KDP)crystals are important materials in high-energy laser ***,because these crystals are brittle and soft,machining-induced defects often emerge in KDP *** study aimed to investigate the material removal mechanisms and characteristics of KDP during nanoscratching using Berkovich,spherical,and conical *** found that KDP surface layers could be removed in a ductile mode at the micro/nanoscale and that dislocation motion was one of the main removal *** characteristics are related to the stress fields generated by indenter *** spherical indenter achieved a ductile removal mode more *** lateral force of nanoscratching increased with an increase in the normal *** coefficient of friction(COF)followed the same trend as the lateral force when spherical and conical indenters were ***,the COF was independent of the normal force when using a Berkovich *** found that these COF variations could be accurately described by friction models.

关键词： Potassium dihydrogen phosphate(KDP)crystals Removal mechanism Nanoscratching Indenter geometry