纳流液相分离与电感耦合等离子体质谱联用技术研究新进展

高效微纳液相分离技术如纳流液相色谱、毛细管电泳、微芯片色谱/电泳等与电感耦合等离子体质谱(ICP-MS)检测技术联用,既具有前端分离技术高选择性、高灵敏度、快速、低样品消耗的特点,又结合了后端ICP-MS检测分辨率高、动态范围宽、可绝对定量等优势,正在发展成为一种重要的高内涵联用分析手段。该文对近年来纳流液相分离与ICP-MS联用装置的发展作一系统介绍,对其在化学与生物化学分析等领域的应用予以综述,并展望了该联用技术的发展前景。国家自然科学基金(21475110,21535007,J1310024);;厦门市科技计划项目(3502Z20173019);;中央高校基本科研业务费(20720160051)~

长期砷暴露的大鼠尿液代谢组学研究

慢性无机砷暴露能够引发多种疾病和损害,但其所涉及的生物学过程尚未完全阐明。全球约有超过2亿人面临饮用水砷污染的威胁。本研究以自由饮水的方式对健康大鼠进行无机砷的长期暴露,并对大鼠尿液的代谢组变化进行系统分析。结果表明,长期砷暴露大鼠的尿液代谢组与对照组具有显著区别,且高剂量砷暴露对大鼠尿液代谢组产生的影响更加显著。本研究共鉴定出36种差异代谢物,其中14种与氨基酸代谢相关的代谢物发生了显著变化,涉及到色氨酸代谢、精氨酸和脯氨酸代谢、赖氨酸降解、β-丙氨酸代谢、半胱氨酸和蛋氨酸代谢、甘氨酸、丝氨酸和苏氨酸代谢;11种与脂类代谢相关的代谢物,涉及到的代谢通路有鞘脂代谢、脂肪酸代谢;同时发现蛋白质的表达与翻译后修饰也受到干扰。这些生物学过程的改变均可作为砷毒性机理的关键分子事件。国家自然科学基金项目(Nos.21475110,21535007,J1310024);;中国博士后基金项目(No.2018M642572);;厦门市科技计划项目(No.3502Z20173019);;中央高校基本科研业务费(No.20720160051)资

How flexibility affects the wake symmetry properties of a self-propelled plunging foil

The wake symmetry properties of a flapping-foil system are closely associated with its propulsive performance. In the present work, the effect of the foil flexibility on the wake symmetry properties of a self-propelled plunging foil is studied numerically. We compare the wakes of a flexible foil and a rigid foil at a low flapping Reynolds number of 200. The two foils are of the same dimensions, flapping frequency, leading-edge amplitude and cruising velocity but different bending rigidities. The results indicate that flexibility can either inhibit or trigger the symmetry breaking of the wake. We find that there exists a threshold value of vortex circulation above which symmetry breaking occurs. The modification of vortex circulation is found to be the pivotal factor in the influence of the foil flexibility on the wake symmetry properties. An increase in flexibility can result in a reduction in the vorticity production at the leading edge because ofthe decrease in the effective angle of attack, but it also enhances vorticity production at the trailing edge because of the increase in the trailing-edge flapping velocity. The competition between these two opposing effects eventually determines the strength of vortex circulation, which, in turn, governs the wake symmetry properties. Further investigation indicates that the former effect is related to the streamlined shape of the deformed foil while the latter effect is associated with structural resonance. The results of this work provide new insights into the functional role of passive flexibility inflapping-based biolocomotion

【研究報告】学校教育におけるICTの活用に関する一考察 -日本および中国における事例調査から

departmental bulletin pape

The Formation of New Immigrant Chinese Communities : The Structure of Social Support as an Analytical Perspective Based on a Field Survey in Ikebukuro

西原和久教授退任記念

Numerical study on hydrodynamic effect of flexibility in a self-propelled plunging foil

The present study is a numerical investigation of the hydrodynamic effects of passive flexibility ona selfpropelled plunging foil. In the model problem, the flow is two-dimensional, incompressible and laminar, while the flexible foil is treated as an inextensible filament. The leading-edge of the foil undergoes a prescribed harmonic oscillation in the vertical direction. Inthe horizontal direction, the foil is free to move and no constraint is imposed. The simulations are performed by using a solver which couples the immersed boundary method for the flow and the finite difference method for the structure. A systematic parametric study has been conducted to investigate the effects of flexibility on important physical quantities such as the cruising speed, swimmingpower and propulsive efficiency. It is found that optimal cruising speed is always achieved in foilswith some passive flexibility and not the rigid ones. Another important finding is that optimum performance is always achieved at a forcing frequencymuch lower than the resonance point. Based on the simulation results, three dynamical states of a self-propelled foil have been identified with the increase of bending rigidity, i.e., non-periodic movement, periodic backward-movement and periodic forward-movement. For a flexible foil in forward movement, depending on the range of bending rigidity, either a deflected or a symmetric vortex street arises as the characteristic wake structure. It is found that moderate flexibility is beneficial to symmetry preservation in the wake, while excessive flexibility can trigger symmetry-breaking. The results obtained in the current work shed some light onthe role of flexibility in flapping-based biolocomotion

串列柔性平板自推进的流固耦合模拟

利用离散流函数算法求解流体运动,用有限差分方法求解柔性平板运动。数值模拟的结果表明,平板初始间距较小时,上下游平板推进速度都变大效率都变高;平板初始间距增大后,上游平板推进性能趋近于单个平板,下游平板的效率仍然较高。虽然上游平板尾迹的平均值是射流,但是下游平板依旧能够提高效率;在下游柔性平板遇到上游平板脱落的涡之前,两个平板的运动模式一样;