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Vortex generator jets (VGJs) have proven to be effective in minimizing the separation losses on low-pressure turbine blades at low Reynolds numbers. Experimental data collected using phase-locked particle image velocimetry and substantiated with a hot-film anemometer were used to answer fundamental questions about the influence of VGJs on a separated boundary layer. The data were collected on the suction surface of the Pack B blade profile, which has a non-reattaching separation bubble beginning at 68% axial chord. Two VGJ pulse histories were created with different frequencies, jet durations,and duty cycles. The mechanisms responsible for boundary layer separation control were shown to be a combination of boundary layer transition and streamwise vortical structures. Jet duration and relaxation time were important VGJ characteristics in determining the extent of control. The unsteady environment characterisitic of the low-pressure turbine section in a gas turbine engine effectively reduces the time-averaged separation zone by as much as 35%. Upstream blade rows create unsteady flow disturbances (wakes) that transition the flow. This transitioned flow propagates downstream, re-attaching the separation bubbles on the subsequent blade row. Phase-locked PIV and hot-film measurements were used to document the characteristics of this separation zone when subjected to synchronized unsteady wakes and VGJs. The phase difference between VGJ actuation and the wake passing, blowing ratio, and VGJ duration were optimized to achieve the greatest timeaveraged control of the separation zone. The experimental data were used to identify the important characteristics of the wake/jet interaction. Phase-locked PIV measurements were taken to isolate the wake event.

锂电池鼻祖J.-M. Tarascon——《Nanostructured materials for advanced energy conversion and storage devices》

The separation bubble on a NACA 0012 airfoil with a two-dimensional, constant span, simulated leading-edge glaze-ice accretion is investigated using Particle Image Velocimetry (PIV). Chordwise PIV measurements, or those along the separation bubble cross-section, are obtained at a Reynolds number of 0.9x106, Mach number of 0.20, and between 0 deg and 5 deg angle-of-attack. Mean reattachment estimated from surface oil-flow visualization indicates increasing bubble length and unsteadiness (based on reattachment zone width) with angle-of-attack, consistent with results extracted from PIV measurements. Timeaveraged streamlines and forward flow intermittency reveal a primary recirculation with clockwise rotation defined by a shear layer and a smaller, secondary recirculation with counter-clockwise rotation directly downstream of the point of separation, both consistent with backward-facing step type flowfields. Mean and RMS velocity component contours highlight these features and wall-normal profiles are extracted and compared to other separation bubble data including those over a backward-facing step and blunt flat plate.

The active control of laminar and turbulent flows with dynamical actuators is of great scientific and technological interest in nearly any field of fluid mechanics. On on hand it becomes possible to generate artifical flow structures whose properties and significance for the turbulent mixing, or their interaction with other flow structures, can be examined. On the other hand, these devices suppress flow separation on profiles or increase the performance of flow engines. Today, most of the well established actuator concepts are based on pneumatic and micro-mechanic basis. However, owing to their limited dynamic range their potential seems to be limited from the present point of view, see Gad-el-Hak (2001), and also their technical implementation is sometimes difficult. In the following an optical actuator concept is proposed and examined that allows to excite the flow non-intrusively with nearly any pulse-width and repetition-rate.

The wake of a circular cylinder at Re = 2700 is investigated by means of Tomographic PIV (Tomo-PIV), a recently developed three-dimensional velocimetry technique. The paper presents the principles of Tomo-PIV and discusses in details the implementation of the technique to the experimental conditions. With a measurement volume of approximately 40x40x10 mm2 two configurations are chosen in order to describe both the 2D wake features and the span wise organization of secondary rollers dominating the 3D flow organization. The present data allow to directly evaluate the measurement error imposing mass conservation inside the volume (viz. solenoidal velocity field). The visualization of the wake instantaneous structure is obtained by means of vorticity vector magnitude iso-surfaces, or decomposing the vorticity in the span wise and stream-wise(normal)/bi-normal component, which return the separate contribution of the Kármán rollers and the interconnecting structures between them respectively. The properties of the secondary rollers are given in terms of span wise wavelength, peak vorticity, vorticity stretching and their size and shape. A value of the span wise wavelength λ z/D = 1.2 is recurring and the rollers organization into pairs is found to be similar to the instability Mode B occurring in lower Reynolds number wakes investigated with previous studies.

The transient behaviour of the fuel spray from an air-assisted fuel injector in a constant volume chamber has been investigated experimentally. The relative Sauter mean diameter (SMD) of the spray droplets was determined using planar laser induced fluorescence (PLIF) and planar Mie scattering. Planar images of the ensemble averaged relative SMD with various injection conditions were obtained by calculating the ratio between the two laser light intensities at a given point. The penetration length and the spray shape factor were also obtained. The ensemble averaged results suggest the existence of vortices that are shed from the injector tip, and which entrain the smaller droplets. Results also show that the characteristics of the injector vary weakly with several particular injection parameters, notably the fuel injection pressure and the delay between fuel and air injection.

Measurements and simulations are presented of the flow past a tailplane research airfoil which is designed to show a mixed leading-edge trailing-edge stall behaviour. The numerical simulations were carried out with two flow solvers that introduce transition prediction based on linear stability theory to RANS simulations for cases involving laminar separation bubbles. One of the methods computes transition locations across laminar separation bubbles whereas the other assumes transition onset where laminar separations occur. For validation of the numerical methods an extensive measurement campaign has been carried out. It is shown, that the methodology mentioned first can simulate the size of laminar separation bubbles for angles of attack up to where the separation bubble and the turbulent separation at the trailing edge are well behaved and steady in the mean. With trailing edge separation involved, the success of the new numerical procedure relies on the diligent choice of a turbulence model. Finally, for flows with increased unsteady behaviour of both, separation bubble and turbulent separation, which were observed at higher angles of attack in the experiment between maximum lift and leading-edge stall, steady state prediction methods for transition can no longer be applied and time-accurate methods have to be developed in a further step.

锂电池的鼻祖J.-M. Tarascon的杰作——《Building better batteries》

（1）现代SEM要求分辨率为纳米级别，高电流，小探针大小，有效的低电压操作。 （2）这些需求使钨灯丝电子枪SEM无法跻身于高端SEM行列。 （3）因此现在所有高性能SEM，都采用一些更先进的电子发射源形式。 （4）钨灯丝电镜的价格仍然较便宜，并能满足多种应用需求。

Fluorescent tracer particles have found a number of uses in PIV. A light sheet produces flare when it impinges upon an object within the field of view, preventing particle images from being obtained and hence preventing velocity measurements in that locality. An example is shown in figure 1 where 532nm light is used for excitation and imaging. Whilst in some situations flare may be minimized by careful experiment setup, in some applications flare is difficult to avoid and prevents information from being obtained, e.g. in boundary layer measurements. A further application has been explored where fluorescent tracers are used to optically label one phase or constituent of a flow and thereby enable simultaneous multi-constituent PIV [1-3]. The general application of fluorescent tracers to gas phase flow seeding requires sufficient fluorescence emission from micron sized tracers when imaged over 10’s of mm field of view. For multi-constituent and multi-phase flows sufficient chromatic separation is also required between the illumination and the fluorescence and between the fluorescence and any wavelengths used for Mie scattering.

Vapor adsorption is an important process influencing the migration and the fates of many organic pollutants in the environment. In this study, adsorption of ethylene glycol (EG) vapor onto single crystal R-Al2O3 (0001) and fused SiO2 (amorphous) surfaces was studied with sum frequency generation spectroscopy, a well-suited surface specific technique for probing interfacial phenomena at the molecular scale. Air-aqueous EG solutions were also investigated to compare to the adsorption at the air-solid interface in the presence of water vapor. The gauche conformer of EG molecules dominates the air-aqueous EG solution interface, and EG molecules act as hydrogen acceptors at the air-liquid interface. Water and surface hydrophilic/ hydrophobic properties play important roles for the adsorption of EG onto silica and alumina surfaces. The adsorbed EG molecules interact in different ways at the two different oxide surfaces. EG molecules weakly physisorb onto the R-Al2O3 (0001) surface by forming relatively weak hydrogen bonds with surface water molecules. On the silica surface, the suppression of the silanol OH stretching peak indicates that EG molecules form hydrogen bonds with silanol OH groups. Introduction

本文详细叙述了当前等压法透气性测试中采用的标定方法——参考膜标定，并对该方法的实际使用情况进行了分析，同时推荐了另一种标定方法——标准气体标定，指出在等压法透气性测试中应采用参考膜标定和标准气体标定两种模式，不但可以为等压法的应用推广扫清障碍并且可以降低使用成本。

特殊的涂层工艺，如 DLC(类金刚石碳膜）PVD (物理气相沉积) 或 CVD (化学气相沉积) 对测量技术提出了挑战。极薄的涂层对测量提出了更高的要求，使得传统的显微硬度计无法对如此薄的涂层/薄膜的机械性能做出正确的测量。 菲希尔（FISCHER）采用仪器化压入测试方法的自动化纳米压痕仪，可以对该类涂层的性能做出快速、准确的测量，十分适用于研发、质量控制、来料检验和过程控制等领域。

A dusty (or complex) plasma is a four-component system composed of ions, electrons,neutral particles and charged microparticles. The presence of the microparticle (i.e.,dust) component alters the plasma environment, giving rise to a wide variety of new plasma phenomena. Recently, the Auburn Plasma Sciences Laboratory (PSL) has acquired and installed a stereoscopic PIV (stereo-PIV) diagnostic tool for dusty plasma investigations [Thomas, et. al., Phys. Plasmas, 11, L37 (2004)]. This presentation discusses the use of the stereo-PIV technique for determining the velocity space distribution function of the microparticle component of a dc glow discharge dusty plasma. These distribution functions are then used to make preliminary estimates of the kinetic temperature of the dust component. The data is compared to a simple energy balance model that relates the dust temperature to the electric field and neutral pressure.

阴极保护是对地下金属管网的稳定运行是非常重要的，无论是输水、输油和输气管线，一般均需要采用外加电流或者牺牲阳极进行保护，并必须确保保护电位在全寿命期均符合设计要求。对于外加电流的阴极保护系统，整流器或恒电位仪的输出电压、输出电流也必须始终受到监控，以确保设备不会因为意外而造成被保护管线的严重伤害；此外对于高阻体系，新的标准还要求通过瞬间断电法来测量管线的真实保护电位，对要外电场干扰严重的区域，还必须对杂散电流进行准确测量。

Two novel techniques based on Laser-Induced Fluorescence (LIF) were applied to measure gas-phase temperature distributions in boundary layers close to wall surfaces. Single line toluene-LIF thermometry was used to image temperature in a nitrogen gas flow above a heated wall. The nitrogen gas flow was doped with evaporated toluene. When excited at 266 nm, the toluene LIF-signal shows an exponential dependence on temperature. This behavior was used to calculate absolute temperatures from LIF images after calibration at known conditions. The second technique, multi-line NO-LIF thermometry was applied to image temperature in the quenching boundary layer close to a metal wall located on a flat flame burner. A small amount of nitric oxide was mixed into the air/methane mixture. NO molecules were excited in the A-X (0,0)-band at 225 nm. NO-LIF excitation spectra were acquired by tuning the excimer laser wavelength and recording the NO LIF-signal with an ICCD camera. Absolute temperatures were calculated for every pixel by fitting simulated excitation spectra to the experimental data. Temperature distributions close to the wall surface were measured at two different flow-rate conditions. A high nominal spatial resolution of 0.016 mm/pixel in direction perpendicular to the wall was reached. Wall surface temperatures were recorded simultaneously by embedded thermocouples and compared with gas-phase temperature near the wall surface.

该资料全面，准确的讲解了高效液相色谱在日常工作中的应用。详细说明了，使用高效液相时应当注意的事项。内容讲到：高效液相色谱（HPLC）分析中，流动相溶剂的纯度和质量对分析结果和仪器本身都有重要影响。溶剂中的各种痕量杂质不仅会造成较高的基线和鬼峰，进而影响定性定量分析结果，而且可能会污染分离柱和堵塞系统，造成仪器出现故障。了解HPLC溶剂规格和相关的测试方法，可以帮助HPLC 用户评价和筛选HPLC溶剂，减少溶剂杂质对应用造成的负面影响。本文介绍了基于紫外（UV）吸收和HPLC梯度确定HPLC级乙腈纯度和质量的两种规范方法及其对HPLC分析的意义，并探讨了这两种方法的实际应用。

在相邻电极的脉冲电子束产生的氩和氧的等离子体中，测量时间分辨离子的流量和能量分布。氩离子和氧离子的能量和流量的时间变化，是跟等离子体的电子温度和离子密度相关的。氧等离子体的延迟时间要比氩的短。这可以通过分析各种离子的损失机理来推断。

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测量样品的量子产率有两种方法： 相对量子产率测量：需要一种已知量子产率的标准品作为参照，通过对标准物和样品进行吸光度和荧光的测量换算得到样品的量子产率。只适用于液体样品。 绝对量子产率测量：不需要 标准样品进行对比，广泛适用于液体、薄膜和粉末样品。在进行测量时需要积分球附件；积分球内表面涂层一般是高反射性材料，比如硫酸钡和聚四氟乙烯。样品表面各个方向的激发光或者是发射光进行积分球均匀化后从出射口出来，并进入到单色器中最后被检测器检测到。

锂电池鼻祖J.-M. Tarascon的杰作——《Nanomaterials for Rechargeable Lithium Batteries》

Lifting surfaces are used both for propulsion and control of sea vessels and must meet performance criteria such as lift, drag, and (in some military applications)hydroacoustic noise limits. Design tools suitable to predict such criteria must handle complex flow phenomena and manage the wide range of flow scales inherent in marine applications (Reynolds numbers ~108). To date, the development of such tools has been limited by the lack of controlled experimental data in this high Reynolds numbers range. Lifting surface flow is the focus of current high Reynolds number experiments involving a two-dimensional hydrofoil in the world’s largest water tunnel, the US Navy’s William B. Morgan Large Cavitation Channel (LCC). The goal of these experiments is to provide a unique high Reynolds number experimental dataset at chord-based Reynolds numbers (Re) approaching those of full-scale propulsors (~108). This data will be used for validation of scaling laws and computational models, with particular emphasis given to the unsteady, separated, turbulent flow at the trailing edge. In addition, these experiments will provide fundamental insight into the fluid mechanics of trailing-edge noise generation in marine propulsion systems. This paper describes the experimental equipment and methods employed in the test program. Described herein is the use of the LCC’s Laser Doppler Velocimetry (LDV) capability to acquire flow velocity mean and turbulence quantities, as well as estimates of boundary layer transition. Also presented is a Particle Imaging Velocimetry (PIV) system developed for these experiments and employing seed injection upstream of the channel’s flow straightener. Finally, a description is given of instrumentation mounted in the foil for measurement of vibration and surface static and dynamic pressures.

微电极的制作是微流控芯片电化学检测的关键技术. 本文提出CO2激光烧蚀结合化学腐蚀快速制作微流控芯片阵列微电极的方法. 此处制作学术交流，不做其他任何商业用途，版权归原作者所有！

Liquid andliquid/gasflowsthroughspacerfilledchannelswerestudiedusingParticleImagingVelocime- try (PIV)toprovideexperimentalsupportforvelocitydistributionsobtainedfromComputationalFluid Dynamics studiesavailableintheliterature.ItisshownthatPIVisasuitabletechniqueformeasuring velocity profilesinspacerfilledchannels,althoughcarehastobetakenwheninterpretingtheresults. PIV measurementswerecarriedoutforanentireflowcell(5cm×15 cm),asmallerareaofroughly 7mm×8mmandforasinglespacercell(2.5mm×3 mm).Theexperimentalresultsshowthatfluidflow is welldistributedacrosstheentireflowcellinthecaseofsingle-phaseflow.Therecordingsofthesingle spacer cellshowedthatliquidflowismainlyparalleltothespacerfilamentsandthereforethedirec- tion offlowchanges90◦ over theheightofthechannel.Introductionofairbubblesintroducedstrong local velocitygradients.Theliquidvelocityintwo-phaseflowsisshowntobemoreunsteadythanin the caseofsingle-phaseflow,whichisadvantageouswhentryingtopreventfoulingorconcentration polarization.

Detection and imaging of multi-reaction zones is an essential tool for understanding the detailed structure of complicated flames. In this work a combined 4-camera technique is presented for multi-reaction zones imaging. The technique combines highly advanced laser-based diagnostics tools, namely Rayleigh scattering, laser-induced predissociation fluorescence (LIPF) of OH, LIF of PAH, and LIF of formaldehyde (CH2O). The application of this combined technique in turbulent non-homogeneous hydrocarbon flames is quite new. The technique shows its ability to detect simultaneously rich, lean and diffusion reaction zones. The 3 reaction zones can be spatially resolved, providing essential information about their interaction and overall flame stability. Therefore, the detection and study of triple flame structures in non-homogeneous turbulent flames becomes possible. An example of a triple flame structure in a turbulent lifted non-premixed methane flame is presented. The present work proves that the developed technique is a powerful tool for multi-reaction zone measurements in turbulent and laminar flames.

在相邻电极的脉冲电子束产生的氩和氧的等离子体中，测量时间分辨离子的流量和能量分布。氩离子和氧离子的能量和流量的时间变化，是跟等离子体的电子温度和离子密度相关的。氧等离子体的延迟时间要比氩的短。这可以通过分析各种离子的损失机理来推断。

For the enhancement of many technical processes like reacting flows, mixing in chemical reactors or mixture formation in combustion engines the knowledge of spatial distribution of species is of great importance. The planar laser-induced fluorescence (PLIF) technique is a well established method to get 2-dimensional maps of concentration or mixture-ratio in a specific plane in the volume of interest. In our recent work we were able to validate a PLIF technique for the quantitative detection of fuel/air ratios (FARLIF) which will be used for mixture-formation investigations in optical engines [1, 2]. In many applications – like mixture-formation in combustion engines – not only the actual species or mixture distribution is of interest. The temporal evolution, the dynamics of the species distribution is often a key for the understanding and improvement of the fluid-dynamic processes.

磁力搅拌器利用了磁场和漩涡的原理，将沉入搅拌子的待搅拌液体之容器放置于磁力搅拌器的底座上，当磁力搅拌器通电后，底座附近产生一个旋转的磁场带动搅拌子成圆周循环运动，进而在容器液体内形成一个漩涡，从而达到搅拌液体的目的。

摘 要：通过宏观检验、化学成分分析、金相检验和能谱分析等手段对冷轧Q195L。带钢表面翘皮缺陷进行分析。结果表明：钢中存在的多种非金属夹杂物、氧化铁皮和保护渣是引起带钢翘皮的主要原因。

The analysis of impurities in Rhodium samples requires an instrument with high resolution to avoid inter-element correction and obtain low detection limits. For this reason the JY ULTIMA was used. This Application Note reports the wavelengths that were used in this difficult matrix and the detection limits obtained.