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On the Difference Between the Skew-rank of an Oriented graph and the Rank of Its Underlying graph

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 129-136页

作者： jia-min Zhu Bo-jun Yuan Yi Wang School of Mathematical Sciences Anhui UniversityHefei230601China School of Science Zhejiang University of Science and TechnologyHangzhou310023China

Let g be a simple graph and g~σ be the oriented graph with g as its underlying graph and orientation σ.The rank of the adjacency matrix of g is called the rank of g and is denoted by r(g).The rank of the skew-adjacency matrix of g~σ is called the skew-rank of g~σ and is denoted by sr(g~σ).Let V(g)be the vertex set and E(g) be the edge set of *** cyclomatic number of g,denoted by c(g),is equal to |E(g)|-|V(g)|+ω(g),where ω(g) is the number of the components of *** is proved for any oriented graph g~σ that-2c(g)≤sr(g~σ)-r(g)≤2c(g).In this paper,we prove that there is no oriented graph g~σwith sr(g~σ)-r(g)=2c(g)-1,and in addition,there are infinitely many oriented graphs g~σ with connected underlying graphs such that c(g)=k and sr(g~σ)-r(g)=2c(g)-l for every integers k,l satisfying 0 ≤l≤4k and l≠1.

关键词： cyclomatic number rank skew-rank

A condition-based maintenance policy for reconfigurable multi-device systems

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Advances in Manufacturing 2024年第2期12卷 252-269页

作者： Shu-Lian Xie Feng Xue Wei-min Zhang jia-Wei Zhu School of Mechanical Engineering Tongji UniversityShanghai201804People’s Republic of China

The exploration of component states for optimizing maintenance schedules in complex systems has garnered significant interest from ***,current literature usually overlooks the critical aspects of system flexibility and *** implementation of system reconfiguration can effectively mitigate system downtime and enhance production *** study proposes a dynamic condition-based maintenance policy considering reconfiguration for reconfigurable systems.A double-layer decision rule was constructed for the devices and *** achieve the best overall maintenance effect of the system,the remaining useful life probability distribution and recommended maintenance time of each device were used to optimize the concurrent maintenance time window of the devices and determine whether to reconfigure them.A comprehensive maintenance efficiency index was introduced that simultaneously considered the maintenance cost rate,reliability,and availability of the system to characterize the overall maintenance *** reconfiguration cost was included in the maintenance *** proposed policy was tested through numerical experiments and compared with different-level *** results show that the proposed policy can significantly reduce the downtime and maintenance costs and improve the overall system reliability and availability.

关键词： Condition-based maintenance(CBM) Reconfigurable system Remaining useful life Maintenance cost System reliability

Surface vitrification of carbon by laser treatment: Insights of glass formation from molecular dynamics

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Journal of Advanced Ceramics 2024年第6期13卷 729-735页

作者： Yanhui Zhang Haifeng Yu Yongying jia Zhisheng Zhao Li-min Wang Riping Liu Center for Advanced Structural Materials State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao 066004China

Microstructural modification of carbon materials,such as carbon fibers(Cf)and pyrolytically deposited carbon,is important for engineering ***,the regulation of these materials is not an effortless *** understand the impacts of thermal spikes from pulsed laser processing on the structural adaptation of amorphous carbon(a-C),we performed melt quenching by molecular dynamics(MD)*** results confirm that the vitrification behavior of carbon can be tuned by adjusting the cooling rate(R),which is controlled by the thermal spikes of laser ***,we set up a two-step way to locate the critical cooling rate(R_(c))of monoatomic carbon,which is refined by the sharp change in the environmental similarity *** this novel technique,we demonstrate that the ordering degree and the local atomic motif can be largely modified by going across a bar of 100 K/ps,which is extracted as the critical cooling rate to ensure the complete amorphization of *** approach provides a criterion for both experimentally processing and theoretically simulating a-C ***,this work provides guidelines on how to tune the amorphous carbon structures of engineering materials and provides an outlook for the wonderland of amorphous carbon materials.

关键词： molecular dynamics(MD) structural order carbon fibers(Cf) vitrification critical cooling rate(R_(c))

Construction of biomimetic proton transport channels in metal-organic framework

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Chinese Chemical Letters 2024年第3期35卷 513-517页

作者： Xiao-min Li Junchao jia Danting Yang jiali Jin Junkuo gao School of Materials Science and Engineering Institute of Functional Porous MaterialsZhejiang Sci-Tech UniversityHangzhou 310018China Zhejia.g Key Laboratory of Pathophysiology School of Public HealthSchool of MedicineNingbo UniversityNingbo 315211China

Construction of proton transport channels in metal-organic frameworks(MOFs)with simple synthesis processes,high proton conductivities and good performance stabilities has been of great interest for proton exchange membrane fuel cell(PEMFC).Herein,we mimic the proton transport behavior of amino acid residues in bacteriorhodopsin,select UiO-66-COOH as the host,glycine and aspartic acid as the functional guest molecules,and then functionalize the MOF framework with amino acids to obtain biomimetic proton transport *** strategy endows UiO-66-COOH-Asp a high proton conductivity of 1.19×10^(-2)S/cm at 70℃and 98%RH,excellent cycle stability of performances and performance durability,which can be comparable to the reported MOFs-based proton ***,the proton conduction mechanism in UiO-66-COOH-Asp is elaborated in detail due to its visual structure,which is also one of the advantages of adopting MOFs as research platform,making it possible to optimize the structure-activity relationship of advanced ***,this strategy has clear objectives and simple synthesis,which has made certain contributions to both theoretical research and future industrial production of proton conductors.

关键词： MOF Amino acids Biomimetic proton transport channels Synergistic effect Proton conduction mechanism

Surface decoration of mesocarbon microbeads with multifunctional TiNbO_(4-x)@C coating layer as high rate and stable anode of Li-ion batteries

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Rare Metals 2024年第5期43卷 2053-2066页

作者： jia-Mei Lai Zhi-min Zou Yu Bai Yu-Tao Xing Chun-Hai jia.g Fujian Provincial Key Laboratory of Functional Materials and Applications Institute of Advanced Energy MaterialsSchool of Materials Science and EngineeringXiamen University of TechnologyXiamen 361024China Shanghai XFH Science and Technology Development Co. Ltd.Shanghai 200949China Fujian XFH New Energy Materials Co. Ltd.Yong'an 366000China Shenzhen XFH Science and Technology Co. Ltd.Shenzhen 518071China Laboratorio de Microscopia Eletronica de Alta Resolucao Centro de Caracterizagao Avangada Para a Industria de Petroleo(LaMAR/CAIPE)Universidade Federal FluminenseNiteroiRJ 24210-346Brazil

Surface modification of graphite anode with electroactive matters has been proven of a more practical strategy in enhancing the performance of Li-ion batteries than exploring alternative novel anode ***,rutile TiNbO_(4-x) nanoparticles with a tunnel structure are employed as multifunctional decoration substances in combination with a carbon coating layer to improve the rate and cycle properties of mesocarbon microbeads(MCMBs).As compared to pristine MCMB,the Li^(+)diffusion coefficients of the composite anodes are enhanced due to the synergistic effect of TiNbO_(4-x)@***,the overcharge and voltage polarization of the composite anodes at high rate are obviously minimized due to the current sharing effect of the high-potential TiNbO_(4-x).Moreover,the amorphous Li_(y)TiNbO_(4-x) converted from TiNbO_(4-x) in the initial lithiation process can deliver pseudocapacitive capacity to the composite anodes from the second *** of these functions of TiNbO_(4-x)@Ccoating layer have directly contributed to the improved rate and cycle performance of the MCMB/TiNbO_(4-x)@C composite *** one containing 12.0 wt%TiNbO_(4-x) exhibits a high reversible specific capacity of 118 m Ah·g^(-1)at 10C(1C=372 m A·g^(-1)),together with a high capacity retention of 90.9%after 300 cycles at 3C,which are all much superior to those of pristine MCMB.

关键词： Li-ion batteries MCMB TiNbO_(4-x)@C Surface decoration Rate capability

Primary acinic cell carcinoma of the breast: A case report and review of literature

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World Journal of Clinical Cases 2024年第1期12卷 196-203页

作者： jia-Sheng Ding min Zhang Fang-Fang Zhou Department of Intensive Care Unit Lishui Central HospitalThe Fifth Affiliated Hospital of Wenzhou Medical UniversityLishui 323000Zhejiang ProvinceChina Department of Pathology Lishui Central HospitalThe Fifth Affiliated Hospital of Wenzhou Medical UniversityLishui 323000Zhejiang ProvinceChina Department of Ultrasound Lishui Central HospitalThe Fifth Affiliated Hospital of Wenzhou Medical UniversityLishui 323000Zhejiang ProvinceChina

BACKgROUND In the current World Health Organization classification,acinic cell carcinoma(AcCC)of the breast is considered a rare histological subtype of triple-negative breast *** of the few reports in the literature,data concerning clinical outcomes are ***,we report a case of AcCC of the breast in a 48-year-old woman.A 48-year-old woman with a mass in her right breast came to our hospital for further *** and an ultrasound(US)scan showed a mass in the upper inner side of the right *** then underwent surgery to resect the mass in her right *** pathological examination revealed that the tumor had abundant acinar-like structures formed by tumor cells with prominent eosinophilic granules in the cytoplasm,consistent with acinar cell *** results of immunohistochemical analysis supported the diagnosis of breast acinar cell *** months later,she underwent breast-conserving surgery and sentinel lymph node *** pTNM stage was *** surgery,the patient received 30 radiotherapy *** patient was followed up for a period of one year,and no recurrence was *** of the breast is a rare type of malignant *** it is usually asym-ptomatic and can be detected by imaging studies,routine breast US or mamm-ograms are ***,there are no characteristic diagnostic imaging findings or clinical manifestations,so immunohistochemical examination is critical for an accurate diagnosis of AcCC of the breast.

关键词： Acinic cell carcinoma Breast Malignant tumor Immunohistochemical Surgery Case report

Beta-alanine promotes angiogenesis in laser-induced choroidal neovascularization mice models

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International Journal of Ophthalmology(English edition) 2024年第9期17卷 1592-1598页

作者： jia-Li Wu min Zhang Xiao-Dong Sun Department of Ophthalmology Shanghai General Hospital(Shanghai First People’s Hospital)Shanghai Jiao Tong UniversitySchool of MedicineShanghai 200080China National Clinical Research Center for Ophthalmic Diseases Shanghai 200080China National Clinical Research Center for Eye Diseases Shanghai 200080China Shanghai Key Laboratory of Fundus Diseases Shanghai 200080China Shanghai Engineering Center for Visual Science and Photomedicine Shanghai 200080China

AIM:To investigate the effect ofβ-alanine(BA)on laserinduced choroidal neovascularization(CNV)mice ***:Laser-induced CNV mice models were established,and BA was administrated for one week and two weeks in advance,***,retinal pigment epithelium(RPE)-choroid flat mounts were separated,and immunohistochemical staining was *** laser-induced CNV lesion areas were measured and *** addition,liver and kidney morphologies were observed to identify potential hepatorenal ***:Enlarged CNV lesion areas were observed in the BA treated *** significant differences were observed in the liver and kidney sections between ***:BA treatment increase CNV lesion areas,suggesting the detrimental effects of BA as a nutritional supplement in age-related macular degeneration(AMD)population.

关键词： age-related macular degeneration choroidal neovascularization β-alanine angiogenesis

Effect of safety valve types on the gas venting behavior and thermal runaway hazard severity of large-format prismatic lithium iron phosphate batteries

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Journal of Energy Chemistry 2024年第2期89卷 195-207,I0006页

作者： Zhuangzhuang jia Yuanyuan min Peng Qin Wenxin Mei Xiangdong Meng Kaiqiang Jin Jinhua Sun Qingsong Wang State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026AnhuiChina gotion High-Tech Co. Ltd.Hefei 230012AnhuiChina

The safety valve is an important component to ensure the safe operation of lithium-ion batteries(LIBs).However,the effect of safety valve type on the thermal runaway(TR)and gas venting behavior of LIBs,as well as the TR hazard severity of LIBs,are not *** this paper,the TR and gas venting behavior of three 100 A h lithium iron phosphate(LFP)batteries with different safety valves are investigated under *** to previous studies,the main contribution of this work is in studying and evaluating the effect of gas venting behavior and TR hazard severity of LFP batteries with three safety valve *** significant results are obtained:(Ⅰ)the safety valve type dominates over gas venting pressure of battery during safety venting,the maximum gas venting pressure of LFP batteries with a round safety valve is 3320 Pa,which is one order of magnitude higher than other batteries with oval or cavity safety valve;(Ⅱ)the LFP battery with oval safety valve has the lowest TR hazard as shown by the TR hazard assessment model based on gray-fuzzy analytic hierarchy *** study reveals the effect of safety valve type on TR and gas venting,providing a clear direction for the safety valve design.

关键词： Lithium iron phosphate battery Safety valve Thermal runaway gas venting behavior Thermal runaway hazard severity gray-fuzzy analytic hierarchy process

Sedimentary architecture of submarine channel-lobe systems under different seafloor topography:Insights from the Rovuma Basin offshore East Africa

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Petroleum Science 2024年第1期21卷 125-142页

作者： Mei Chen Sheng-He Wu Rui-Feng Wang jia-jia Zhang Peng-Fei Xie min Wang Xiao-Feng Wang Ji-Tao Yu Qi-Cong Xiong State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of geosciences China University of Petroleum(Beijing)Beijing102249China Faculty of geosciences University of BremenBremen28359Germany MARUM-Center for Marine and Environmental Sciences University of BremenBremen28359Germany Research institute of Petroleum Exploration and Development PetroChinaBeijing10083China School of geosciences Yangtze UniversityWuhan 100083HubeiChina CNODC Mozambique Ltd. Beijing 100034China

Seafloor topography plays an important role in the evolution of submarine ***,it is still not so clear how the shape of slope affects the three-dimensional(3-D)architecture of submarine *** this study,we analyze the effect of topography factors on different hierarchical lobe architectures that formed during Pliocene to Quaternary in the Rovuma Basin offshore East *** characterize the shape,size and growth pattern of different hierarchical lobe architectures using 3-D seismic *** find that the relief of the topographic slope determines the location of preferential deposition of lobe complexes and single *** the topography is irregular and presents topographic lows,lobe complexes first infill these *** lobes are deposited preferentially at positions with higher longitudinal(***-slope)slope *** the longitudinal slope becomes higher,the aspect ratio of the single lobes ***(***-slope)topography does not seem to have a strong influence on the shape of single lobe,but it seems to affect the overlap of single *** the lateral slope gradient is relatively high,the single lobes tend to have a larger overlap ***,as the average of lateral slope and longitudinal slope gets greater,the width/thickness ratio of the single lobe is smaller,*** tend to accumulate *** results demonstrate that the shape of slopes more comprehensively influences the 3-D architecture of lobes in natural deep-sea systems than previously other lobe deposits and analogue experiments,which helps us better understand the development and evolution of the distal parts of turbidite systems.

关键词： Submarine fan Seafloor topography Sedimentary architecture Slope system SW Indian ocean