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Low-temperature molten salt synthesis and luminescence properties of Eu(Ⅲ)-based coordination polymer nanosheets

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Rare Metals 2021年第3期40卷 728-735页

作者： lei wang Hao Liu Shuang Huang Sheng-Liang zhong College of Chemistry and Chemical Engineering Jiangxi Normal UniversityNanchang 330022China

In this work,Eu(III)-based coordination polymer(EuCP) nanosheets were successfully synthesized using tetrabutylammonium bromide(TBAB) as low-temperature molten salt(LMS),terephthalic acid(PTA) and pyromellitic acid(PMA) as organic building blocks at 160℃.X-ray diffraction(XRD),Fourier transform infrared(FTIR),scanning electron microscopy(SEM),transmission electron microscopy(TEM) and thermogravimetry and differential thermal analysis(TG-DTA) were used to characterize the obtained *** show that the nanosheets have an average size of 200 nm and a thickness of about 50 *** effect of reaction temperature,reaction time and molar ratio of Eu^(3+)/PTA/PMA on the preparation was *** turns out that all of them have great effect on morphology and size of the final *** excited with 315 nm,strong emission centering at 617 nm is ***,this synthetic methodology may offer a new alternative in the preparation of rare earth nanomaterials.

关键词： Molten salt Coordination polymer Rare earth Nanosheets

Multifractal analysis of surface EMG signals for assessing muscle fatigue during static contractions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第6期8卷 910-915页

作者： wang Gang REN Xiao-mei LI lei wang Zhi-zhong Department of Biomedical Engineering Shanghai Jiao Tong University Shanghai 200240 China

This study is aimed at assessing muscle fatigue during a static contraction using multifractal analysis and found that the surface electromyographic （SEMG） signals characterized multiffactality during a static contraction. By applying the method of direct determination ofthef（a） singularity spectrum, the area of the multifractal spectrum of the SEMG signals was computed. The results showed that the spectrum area significantly increased during muscle fatigue. Therefore the area could be used as an assessor of muscle fatigue. Compared with the median frequency （MDF）--the most popular indicator of muscle fatigue, the spectrum area presented here showed higher sensitivity during a static contraction. So the singularity spectrum area is considered to be a more effective indicator than the MDF for estimating muscle fatigue.

关键词： Muscle fatigue Surface electromyographic (SEMG) signals Multifractal Static contraction

Two-dimensional Boron Nitride for Electronics and Energy Applications

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Energy & Environmental Materials 2022年第1期5卷 10-44页

作者： Jiemin wang Liangzhu Zhang Lifeng wang Weiwei lei zhong-Shuai Wu School of New Energy and Materials Southwest Petroleum UniversityChengdu Sichuan 610500China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China Institute for Frontier Materials Deakin UniversityWaurn Ponds CampusLocked Bag 20000Geelong Vic.3220Australia Dalian National Laboratory for Clean Energy Chinese Academy of Sciences457 Zhongshan RoadDalian 116023China

Two-dimensional(2D)boron nitride(BN),the so-called“white graphene,”has demonstrated a great potential in various fields,particularly in electronics and energy,by utilizing its wide bandgap(~5.5 eV),superior thermal stability,high thermal conductance,chemical inertness,and outstanding dielectric ***,to further optimize the performances from the view of structure-property relationship,the determinative factors such as crystallite sizes,layer thickness,dispersibility,and surface functionalities should be precisely controlled and ***,in this review,the synthesis and functionalization methods including“top-down”and“bottom-up”strategies,and non-covalent and covalent modifications for 2D BN are systematically classified and discussed at first,thus catering for the requirements of versatile ***,the progresses of 2D BN applied in the fields of microelectronics such as fieldeffect transistors and dielectric capacitors,energy domains such as thermal energy management and conversion,and batteries and supercapacitors are summarized to highlight the importance of 2D ***,these contents not only contain the state-of-the-art 2D BN composites,but also bring the current novel design of 2D BN-based microelectronic ***,the challenges and perspectives are proposed to better broaden the scope of this ***,this review will pave an all-around way for understanding,utilizing,and applying 2D BN in future electronics and energy applications.

关键词： boron nitride electronics energy functionalization nanosheets two-dimensional materials

EFFECT OF ULTRASONIC POWER ON THE HEAVY ALUMINUM WEDGE BONDING STRENGTH

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Chinese Journal of Mechanical Engineering 2005年第4期18卷 515-518页

作者： wang Fuliang Han lei zhong Jue College of Mechanical and Electrical Engineering Central South UniversityChangsha 410083 China

Eleven groups of wire bonding experiments are carried out on an experiment platform （restructured with a U3000 heavy aluminum wedge wire bonder）. Pure silicon aluminum wire （300 μm in diameter, 2.94-3.92 N in average pull force） and nickel coated aluminum substrates are used in the experiments. During the experiment process, only ultrasonic power rate parameter is changed and the other bonding parameters are kept as constant, The bonding force and time are 4.90 N and 100 ms respectively. After the bonding experiments, shear strength tests are carried out on the bonds as the bonding strength criterion. From those experiments and test results, some conclusions are obtained： In the small ultrasonic power rate conditions （about 20%-30%）, with the power increasing, the bonding strength enhances accordingly; However, in the large ultrasonic power rate conditions （about 45%-70%）, the bonding strength decreases accordingly and over bonding happens. Only when the ultrasonic power rate is in a moderate condition （about 35%-40%） can good and stabilized bonding strength be acquired.

关键词： Ultrasonic wire bonding Ultrasonic power Over bonding Heavy aluminum wire

212例儿童脑囊虫病患者的临床及影像学分析

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地方病通报 2004年第3期19卷 41-42页

作者：王中磊戴伟马巧荣刘玉磊胡颖新山东省寄生虫病防治研究所山东济宁272033

目的探讨儿童脑囊虫病的临床特点及CT特征。方法对 2 12例儿童脑囊虫病患者的临床表现和CT资料进行统计分析。结果儿童脑囊虫病患者主要通过使用被绦虫卵污染的饮食而感染。发病年龄集中在 8～ 11岁 ,农村高于城镇。临床上以癫痫发作和... 详细信息

目的探讨儿童脑囊虫病的临床特点及CT特征。方法对 2 12例儿童脑囊虫病患者的临床表现和CT资料进行统计分析。结果儿童脑囊虫病患者主要通过使用被绦虫卵污染的饮食而感染。发病年龄集中在 8～ 11岁 ,农村高于城镇。临床上以癫痫发作和头痛为主。CT异常率为 82 .5 %,主要表现为片状和圆形的低密度影和少量的高密度影。经 2～ 4个疗程的抗囊治疗后 ,2 12例患儿疗效均达到治愈标准。有 12 8例患者复查了头颅CT ,其中 12 6例 ( 98.4%)患者的低密度影消失 ,2例 ( 1.6%)转化为点状钙化。结论儿童脑囊虫病患者以异体感染为主 ,癫痫发作和头痛是其主要临床表现 ,抗囊治愈率为 10 0 %。

关键词：儿童脑囊虫病临床影像学

多晶Li3+xV1-xTxO4（T=Ge,Si）离子导电性能的改善

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物理学报 1984年第12期 1700-1706页

作者：王超英王连忠石磊陈立泉中国科学院物理研究所中国科学技术大学物理系中国科学院物理研究所 83届毕业生

本文用阻抗谱方法研究了Li3+xV1-xTxO4（T=Si,Ge）多晶的离子导电性,发现一些工艺条件如成型压强、烧结时间和烧结程序对电导率有很大影响。注意分析了这些影响的物理起因。最佳工艺条件是:在大约8t/cm2压强下成型样品。在1000℃连续烧... 详细信息

本文用阻抗谱方法研究了Li3+xV1-xTxO4（T=Si,Ge）多晶的离子导电性,发现一些工艺条件如成型压强、烧结时间和烧结程序对电导率有很大影响。注意分析了这些影响的物理起因。最佳工艺条件是:在大约8t/cm2压强下成型样品。在1000℃连续烧结5至6天,烧结过程中,应尽量避免温度波动。在此条件下制备的Li3.5V0.5Ge0.5O4和Li3.3V0.7Si0.3O4多晶样品在25℃的离子电导率分别为2.2×10-5Q-1cm-1和1.9×10-5Q-1cm-1。

关键词：多晶材料电导率电性离子导电性烧结时间 x)TxO4 x)V Li Ge

有限元分析不同内固定方式治疗肱骨近端骨折的力学差异

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中国组织工程研究 2025年第15期29卷 3101-3109页

作者：王磊王清张申申福建医科大学附属闽东医院福建省福安市355000 福建医科大学福建省福州市350108

背景:目前临床中治疗肱骨近端骨折的钢板内固定方式仍无绝对标准,但重建内侧肱骨距并有效抵抗肱骨头内翻移位是实现肱骨近端骨折坚强固定的要点。目的:利用有限元分析技术获得3种内固定方式作用于肱骨近端骨折的力学差异,对比何种内固... 详细信息

背景:目前临床中治疗肱骨近端骨折的钢板内固定方式仍无绝对标准,但重建内侧肱骨距并有效抵抗肱骨头内翻移位是实现肱骨近端骨折坚强固定的要点。目的:利用有限元分析技术获得3种内固定方式作用于肱骨近端骨折的力学差异,对比何种内固定方法可以提供更加稳定的固定支撑。方法:选择一名健康女性志愿者进行左肩关节的CT扫描,通过有限元分析软件构建肱骨近端骨折伴内侧柱支撑缺损模型。根据钢板内固定方式将模型划分为3组:A组仅在外侧应用Philos钢板固定;B组外侧应用Philos钢板联合内侧微型直行锁定加压板固定;C组外侧Philos钢板联合前内侧微型直行锁定加压板固定。在相同的固定支撑和约束条件下,采用ANSYS分析软件评估3组内固定模型的生物力学稳定性。结果与结论:①3组内固定模型的内固定物应力均未超过450 MPa;②不同载荷条件下,A组肱骨和内固定物的应力较高于B、C两组,而C组的肱骨和内固定物的应力均为最小值;③在屈曲载荷条件下,C组的相对位移对比A、B两组数值较小;④所有载荷条件下,B组的骨折端相对位移是最小的;在内收、外展以及轴向压缩的载荷条件下,B组的相对位移大约只有A组的一半;⑤C组与B组之间的相对位移并没有显著的差异,且C组的相对位移也均小于A组;⑥结果发现,相较于仅应用外侧Philos钢板,外侧Philos钢板与内侧微型直行锁定加压板的联合应用,以及外侧Philos钢板与前内侧微型直行锁定加压板的联合应用,均展现出显著的内固定系统稳定性,后两种组合在内固定系统稳定性上并未呈现出明显差异;综合考虑临床实践中的操作难易程度,外侧Philos钢板与前内侧微型直行锁定加压板的联合内固定方式治疗肱骨近端骨折可能更具优势。

关键词：肱骨近端骨折内侧柱重建 Philos钢板双钢板有限元分析

Effect of sediment particles on the velocity profile of sediment-water mixtures in open-channel flow

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International Journal of Sediment Research 2023年第3期38卷 361-373页

作者： lei Zhang Jianzhao Guan Deyu zhong Yousheng wang State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower Research Joint Sponsored State Key Laboratory of Plateau Ecology and Agriculture Qinghai University State Key Laboratory of Hydroscience and Engineering Tsinghua University

The presence of sediment particles in open-channel flow has an important effect on turbulence; thus, an empirical, turbulent eddy viscosity formula was established for application in the limit for low concentrations. The current study establishes a theoretical relation for the mixture viscosity based on the two-phase mixture model. The percentage contribution of the three mechanisms of mixture viscosity,namely, fluid turbulence(FT), particle turbulence(PT), and inter-particle collisions(IPCs), was calculated under different conditions. The study results indicate that the contribution of FT is dominant, whereas those of PT and IPCs are not significant when the particle inertia(PI) is small, suggesting that the movement of sediment-laden flows is mainly controlled by the fluid properties. The effects of PT and IPCs increase with increases in sediment concentration and PI. Specifically, the effect of collisions among particles generally becomes dominant near the bed surface. A good agreement between the calculated velocity profile of the mixture and available experimental data for large particle sizes and high concentrations proves that the proposed relation for mixture viscosity is more reasonable than the previous empirical relation owing to the consideration of the effects of PT and IPCs, and, thus, can be applied to both dilute and dense suspensions.

关键词： Velocity profile Sediment particles Viscosity Collisions Turbulence

Joint mission and route planning of unmanned air vehicles via a learning-based heuristic

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Journal of Systems Engineering and Electronics 2023年第1期34卷 81-98页

作者： SHI Jianmai ZHANG Jiaming lei Hongtao LIU zhong wang Rui College of Systems Engineering National University of Defense TechnologyChangsha 410073China

Unmanned air vehicles(UAVs) have been regularly employed in modern wars to conduct different missions. Instead of addressing mission planning and route planning separately,this study investigates the issue of joint mission and route planning for a fleet of UAVs. The mission planning determines the configuration of weapons in UAVs and the weapons to attack targets, while the route planning determines the UAV’s visiting sequence for the targets. The problem is formulated as an integer linear programming model. Due to the inefficiency of CPLEX on large scale optimization problems, an effective learningbased heuristic, namely, population based adaptive large neighborhood search(P-ALNS), is proposed to solve the model. In P-ALNS, seven neighborhood structures are designed and adaptively utilized in terms of their historical performance. The effectiveness and superiority of the proposed model and algorithm are demonstrated on test instances of small, medium and large sizes. In particular, P-ALNS achieves comparable solutions or as good as those of CPLEX on small-size(20 targets)instances in much shorter time.

关键词： unmanned air vehicle(UAV) mission planning routing adaptive large neighborhood search