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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 606-612页

作者：吴建磊 CHEN Junzhu TIAN Xiaokun LI Jiahao GAO Wenkai yue yunlong 康俊峰 School of Materials Science and Engineering University of JinanJinan 250022China CDGM GLASS Co.LTD Chengda 610199China

In this work,the structure,viscosity and ion-exchange process of Na_(2)O-MgO-Al_(2)O_(3)-SiO_(2) glasses with different Al_(2)O_(3)/SiO_(2) molar ratios were *** results showed that,with increasing Al_(2)O_(3)/SiO_(2) ratio,the simple structural units Q_(1) and Q_(2) transformed into highly aggregated structural units Q_(3) and Q_(4),indicating the increase of polymerization degree of glass ***,the coefficient of thermal expansion decreased from 9.23×10^(-6)℃^(-1) to 8.88×10^(-6)℃^(-1).The characteristic temperatures such as melting,forming,softening and glass transition temperatures increased with the increase of Al_(2)O_(3)/SiO_(2) ratio,while the glasses working temperature range became *** increasing Al_(2)O_(3)/SiO_(2) ratio and prolonging ion-exchange time enhanced the surface compressive stress(CS)and depth of stress layer(DOL).However,the increase of ion exchange temperature increased the DOL and decreased the CS affected by stress *** was a good linear relationship between stress relaxation and surface compressive *** strengthening significantly improved the hardness of glasses,which reached the maximum value of(622.1±10)MPa for sample with Al_(2)O_(3)/SiO_(2) ratio of 0.27 after heat treated at 410℃for 2 h.

关键词： network structure viscosity ion exchange aluminosilicate glass

双反转恢复序列对急性缺血性脑卒中患者脑白质高信号病灶的探测价值研究

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中华神经医学杂志 2024年第2期23卷 140-145页

作者：陈佳琦岳云龙付睿牛睿首都医科大学附属北京世纪坛医院神经内科北京100038 首都医科大学附属北京世纪坛医院核磁共振室北京100038 首都医科大学附属北京世纪坛医院全科医学科北京100038

目的评价双反转恢复(DIR)序列对急性缺血性脑卒中患者脑白质高信号(WMH)的检测效果,并与T2WI、液体衰减反转恢复(FLAIR)序列进行对比。方法选择首都医科大学附属北京世纪坛医院神经内科自2018年11月至2021年3月收治的发病14 d内且存在WM... 详细信息

目的评价双反转恢复(DIR)序列对急性缺血性脑卒中患者脑白质高信号(WMH)的检测效果,并与T2WI、液体衰减反转恢复(FLAIR)序列进行对比。方法选择首都医科大学附属北京世纪坛医院神经内科自2018年11月至2021年3月收治的发病14 d内且存在WMH的73例急性缺血性脑卒中患者,采用MRI T2WI、FLAIR及DIR序列分别检测WMH。根据Fazekas量表评分将存在侧脑室旁白质高信号(PVWMH)及深部白质高信号(DWMH)患者分别分为轻度组(0~1分)及中重度组(≥2分)。比较T2WI、FLAIR及DIR序列检测的WMH体积,孤立病灶的信号强度、截面积、对比度的差异。结果 (1)73例患者检出PVWMH,其中轻度组36例,中重度组37例。在中重度组患者中,与DIR序列比较,FLAIR序列检测的PVWMH体积较大,差异有统计学意义(P<0.05);与FLAIR序列比较,T2WI序列检测的PVWMH体积较小,差异有统计学意义(P<0.05)。57例患者检出DWMH,其中轻度组44例,中重度组13例。无论是轻度组还是中重度组患者,与DIR序列比较,FLAIR、T2WI序列检测的DWMH体积较大,差异均有统计学意义(P<0.05)。(2)共检出孤立病灶60个,长径5.0~9.1 mm。与DIR序列比较,FLAIR、T2WI序列检测孤立病灶的截面积较大、信号强度较高、对比度较低,差异均有统计学意义(P<0.05)。与FLAIR序列比较,T2WI序列检测孤立病灶的信号强度、对比度较高,差异均有统计学意义(P<0.05)。结论 DIR序列探测WMH效果优于FLAIR和T2WI序列。DIR序列与FLAIR、T2WI序列WMH不匹配区域提示可能存在WMH半暗带。

关键词：脑白质高信号双反转恢复序列脑白质高信号半暗带

Applying heteroatom co-doped carbon nanotube for manifesting high performance in the electrochemical reduction of aqueous nitrogen oxide by gold nanoparticles

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Nano Research 2024年第3期17卷 1151-1164页

作者： Jane Chung Haibo Yin Rong Wang yunlong Wang Junyang Zhang yue Peng Joung Woo Han Seongyun Ryu Junhua Li State Key Joint Laboratory of Environment Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing 100084China EHS Research Center Samsung Electronics Co.Ltd.Gyeonggi-do 18448Republic of Korea

Electrochemical NO-to-NH_(3) under ambient conditions could be a viable alternative having advantages in terms of energy consumption and exhaust gas recycling of NO,replacing a traditional ammonia synthesis method of the Haber–Bosch *** synthesizing boron(B-)and nitrogen(N-)co-doped carbon nanotube(CNT)based gold(Au)catalysts,B-dopants elevate the conductivity of carbon nanotube by sp2 hybridization on graphene and implant B–N domains within the graphene layer,and result in facilitating the embedding amount of Au accompanied by high dispersibility with low particle *** density functional theory(DFT)calculations elucidate that the electron cloud transmitted from B-dopant to the active site of Au induces the Lewis acidic site,and the O-distal pathway occurs following a spontaneous *** of the electron-deficient B-doping area accompanied by N-defects and B–O edges retains the major valence state of Au as Au^(δ+),and suppresses hydrogen evolution reaction(HER)by repulsing the hindrance of H*.This record exhibits the highest faradaic efficiency(FE)of 94.7%,and NH_(3) yield rate of 1877.4μg·h^(-1)·mg_(cat)^(-1),which is the optimal yield over energy consumption in the field of the ambient reduction of aqueous NO.

关键词： boron heteroatom nitrogen defect gold nanoparticles valence states of gold electrochemical NO-to-NH3

Microstructures and Mechanical Properties of TiC Particle Reinforced TiAl Composites by Spark Plasma Sintering

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Journal of Wuhan University of Technology(Materials Science) 2007年第2期22卷 291-294页

作者：岳云龙 School of Materials Science and Engineering Jinan University

Using spark plasma sintering（SPS） technique, TiC particle reinforced γ-TiAl composites were prepared with varying weight fraction of TiC powders. The effects of the TiC fractions and distributions on the properties of the composites were investigated. The composite containing 7wt% TiC had the optimum three-point bending strength of 842 MPa,which was 200 MPa greater than that of the unreinforced γ-TiAl intermetallic. The degradation of the bending strength occurred in the composites containing more than 7wt% TiC and this was believed to be attributed to agglomerated particles of TiC, which acted as crack initiation and propagation sites. The increase of strength in TiC reinforced IMCs came from the grain refinement and the interaction of dislocations with the reinforcing particles. The bending strength of the IMC containing 7wt% TiC was theoretically estimated to increase by 85 MPa and 200 MPa, respectively, by the grain refinement and dislocation strengthening, the total of which was ahnost in accordance with the improvement in that of the unreinforced γ-TiAl intermetallic when considering normal estimation errors.

关键词： TiC / TiAl composites mechanical properties grain refinement dislocation strengthening SPS sintering technique

从传统管理到现代治理——事业单位改革的目标取向及路径选择

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中国行政管理 2008年第4期 36-38页

作者：岳云龙中央编办国家事业单位登记管理局局长北京100010

事业单位应深化改革,已形成较为广泛的共识。改什么,怎样改,是当前迫切需要解决的问题。本文从回顾和总结以往几十年我国事业单位管理和改革历程的经验得失入手,提出了深化事业单位改革的目标取向、路径选择及切入点。

关键词：事业单位改革传统管理现代治理目标取向路径选择事业单位法人治理结构

Fractural research on Ti2AlC/TiAl compound materials

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Fractural research on Ti2AlC/TiAl compound materials

Product Form Solution of a Queuing-Inventory System with Lost Sales and Server Vacation

The 1st International Congress on Advanced Materials 2011

作者： Yang Li yunlong yue Haitao Zhang Ming Wen School of Materials Science and Engineering University of Jinan School of Chemistry and Chemical Engineering University of Jinan

This research indicated that the SEM images of Ti2 AlC/TiAl materials with different samples showed different fractal dimension..In Multi-fractal spectrum,the parameter is calculated by MATLAB through analysis the multi-fractal spectrum *** r=0.00625,giving rise to the small fluctuate,lnχq（r） and lnr shows the well linear relationship in spite of the value of q.τ（q） and q show nonlinear relationship result in the protuberance existed in q ∈ [-3,-1],D（q） and q turn to be more steep,at last the clock shape relationship between the αand f（α） reveal the good symmetry of spectrum,uneven distribution of the fracture,multi-fractal feature clearly

关键词： Ti2AlC/TiAl Microstructure compound Boxing dimension Multi-fractal spectrum

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Journal of Systems Science & Complexity 2024年第2期37卷 729-758页

作者： yue Dequan ZHANG Yuying XU Xiuli yue Wuyi School of Science Yanshan UniversityQinhuangdao 066004China School of Economics and Management Yanshan UniversityQinhuangdao 066004China The Kyoto College of Graduate Studies for Informatics Kyoto City 606-8225Japan

In this study,the authors consider an M/M/1 queuing system with attached inventory under an(s,S)control *** server takes multiple vacations whenever the inventory is *** is assumed that the lead time and the vacation time follow exponential *** authors formulate the model as a quasi-birth-and-dearth(QBD)process and derive the stability condition of the ***,the stationary distribution in product form for the joint process of the queue length,the inventory level,and the server’s status is ***,the conditional distributions of the inventory level when the server is on and operational,and when it is off due to a vacation,are *** the stationary distribution,the authors obtain some performance measures of the *** authors investigate analytically the effect of the server’s vacation on the performance ***,several numerical examples are presented to investigate the effects of some parameters on the performance measures,the optimal policy,and the optimal cost.

关键词： Cost function multiple vacations product form solution queuing-inventory system (s S)control policy

Machine learning-assisted smart epitaxy ofⅢ-Ⅴsemiconductors

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Science China Materials 2024年第9期67卷 3041-3042页

作者： yue Hao Key Laboratory of Wide Band Gap Semiconductor Technology School of MicroelectronicsXidian UniversityXi’an710071China

Semiconductor epitaxial growth is the front-end process for manufacturing microelectronic and optoelectronic *** beam epitaxy(MBE),capable of precisely controlling atomic layer deposition,has emerged as a crucial technique in chip atomic-level manufacturing[1].However,in semiconductor epitaxy,the heterogeneous nature of materials is complicated,and the growth condition fluctuations poses significant challenges in defect suppression[2],substantially impacting chip performance and yield.

关键词： optoelectronic smart semiconductors

Elite Dung Beetle Optimization Algorithm for Multi-UAV Cooperative Search in Mountainous Environments

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Journal of Bionic Engineering 2024年第4期21卷 1677-1694页

作者： Xiaoyong Zhang Wei yue The College of Marine Electrical Engineering Dalian Maritime UniversityDalian116026China

This paper aims to address the problem of multi-UAV cooperative search for multiple targets in a mountainous environment,considering the constraints of UAV dynamics and prior environmental ***,using the target probability distribution map,two strategies of information fusion and information diffusion are employed to solve the problem of environmental information inconsistency caused by different UAVs searching different areas,thereby improving the coordination of UAV ***,the task region is decomposed into several high-value sub-regions by using data clustering *** on this,a hierarchical search strategy is proposed,which allows precise or rough search in different probability areas by adjusting the altitude of the aircraft,thereby improving the search ***,the Elite Dung Beetle Optimization Algorithm(EDBOA)is proposed based on bionics by accurately simulating the social behavior of dung beetles to plan paths that satisfy the UAV dynamics constraints and adapt to the mountainous terrain,where the mountain is considered as an obstacle to be ***,the objective function for path optimization is formulated by considering factors such as coverage within the task region,smoothness of the search path,and path *** effectiveness and superiority of the proposed schemes are verified by the simulation.

关键词： Mountainous environment Multi-UAV cooperative search Environment information consistency Elite dung beetle optimization algorithm(EDBOA) Path planning

Switching,explosion,and chaos of multi-wavelength soliton states in ultrafast fiber lasers

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 82-90页

作者： Zhi-Zeng Si yue-yue Wang Chao-Qing Dai College of Optical Mechanical and Electrical EngineeringZhejiang A&F UniversityLin’an 311300China

Because of the complexity and difficulty of realizing a multi-wavelength soliton state,reports on its internal dynamic characteristics are *** this study,the switching and periodic soliton explosion processes of the multi-wavelength soliton state in a negative dispersion passively mode-locked fiber laser are *** generation of the multi-wavelength soliton state undergoes the process of noise,oscillation,and stable mode-locking,and the splitting and annihilation of solitons with different group velocities directly impact the generation and disappearance of three *** and negative dispersion lead to different group velocities of *** presence and displacement of solitons with different group velocities cause soliton collisions,which lead to soliton explosions.A soliton experiences relative phase oscillation,chaos,and oscillation,as well as convergence and separation before and after an *** an increase in parameters related to pump power,single-soliton oscillation,multi-wavelength solitons,and chaos are found in experiments and simulations,proving the relevance and reliability between simulation and experimental *** work promotes the dynamical study of multi-soliton collisions in nonlinear science and the development of chaos theory in multi-comb lasers.

关键词： multi-wavelength fiber laser soliton explosion chaos state switching real-time dynamics