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Geostrophic adjustment of an isolated axisymmetric lens was examined to better understand the dependence of radial displacements and the adjusted velocity on Burger number and the geometry of initial conditions. The behavior of the adjustment was examined using laboratory experiments and numerical simulations, which were in turn compared to published analytical solutions. Three defining length scales of the initial conditions were used to distinguish between various asymptotic behaviors for large and small Burger number: the Rossby radius of deformation, the horizontal length scale of the initial density defect, and the horizontal length scale of the initial pressure gradient. Numerical simulations for the fully nonlinear time dependent adjustment agreed both qualitatively and quantitatively with analogous analytical solutions. For large Burger number, similar agreement was found in laboratory experiments. Results show that a broad range of final states can result from different initial geometries, depending on the values of the relevant length scales, and the Burger number computed from initial conditions. For Burger number much larger or smaller than unity, differences between different initial geometries can readily exceed an order of magnitude for both displacement and velocity.

在样品前处理过程中，浓缩常常是实验当中不可缺少的一个步骤，尤其是有大量样品需要浓缩时，整个过程显得十分冗长且繁琐，且氮吹耗气量很大，平行性不佳。莱伯泰科美国公司精心设计推出了MV -5多通道平行浓缩仪，可同时多位使用，氮吹针可随液面自动升降，有效地解决了传统氮吹仪的问题。?本文针对实验当中用户最关心的浓缩效率及成运行本方面，特别是耗气量，对MV -5多通道平行浓缩仪进行了考察。

Stratified exchange flows driven by a density difference are found in many natural water bodies and in the atmosphere. A typical case in nature is the strait of Gibraltar, where the water of the Mediterranean Sea flows under the less saline water of the Atlantic Ocean. At the interface between the layers shear is responsible for instabilities (Kelvin-Helmholtz), which results in turbulent mixing and entrainment. Gaining deeper understanding of these processes is the main motivation for this thesis. An experimental study into the development of a mixing layer of a two layer stratified exchange flow is performed and an LIF measurement system was used to obtain the concentration fields. The main objectives of this study were to calibrate and understand the experimental set-up and to investigate the influence of four different parameters on the development of the mixing layer. The calibration of the experimental set-up has led to a simple calibration procedure, which was applied with success. To study the development of the mixing layer the influence of four different parameters was analyzed namely: the buoyant acceleration, the bottom friction, the water depth and the sill slope. After careful analysis of the experimental results it was observed that fluid from the upper layer was entrained into the lower layer in all the experiments. Analysis of the dye visualization showed that the large-scale structures, the Kelvin-Helmholtz instabilities, are mainly responsible for the mixing and entrainment. The overall conclusion was that the variation of geometric condition on the development of the mixing layer has a much stronger influence than the variation of the hydraulic conditions. An enhanced bottom friction affected the Kelvin-Helmholtz instabilities but the mechanism is not completely understood by the author.

This paper presents quantitative planar laserinduced fluorescence (PLIF) imaging of nitric oxide (NO) in a transient-arc direct-current plasmatron igniter using premixed air/fuel mixtures. Quantitative measurements of NO are reported as a function of gas flow rate (20–50 standard cubic feet per hour), plasma power (100–900 mA, 150–750 W), and equivalence ratio (0.7–1.3). Images were corrected for temperature effects by using 2-D temperature field measurements obtained with infrared thermometry and calibrated by a more accurate multiline fitting technique. The signals were then quantified using an NO addition method and spectroscopic laser-induced fluorescence modeling of NO. NO PLIF images and single-point NO concentrations are presented for both plasma-discharge-only and methane/air plasma-enhanced combustion cases. NO formation occurs predominantly through N2(v) + O → NO + N for the plasmadischarge- only case without combustion. The NO concentration for the plasma-enhanced combustion case (500–3500 ppm) was an order of magnitude less than the plasma-discharge-only case (8000–15 000 ppm) due to the reduction of plasma reactions by the methane. Experiments show the linear decay of NO from equivalence ratio 0.8–1.2 under the same flow condition and discharge current. Index Terms—Nitric oxide (NO), plasma torch, plasma-assisted combustion.

解决了研磨过程中粘罐或者沉淀的问题，比如有些物料，比如潮湿的土壤料、沥青矿等粘性料、某些化学品、活性炭、金属粉等，在研磨完毕后物料会沉积于研磨罐底部，磨球及盖子上也粘有很多物料，难于清洗。并且一旦沉底粘罐，磨球只作用于表层物料，使得内部研磨不到，勉强用工具取下，粒度分布也不均匀。

基本的概念及操作须知 · 离心机高速运转，产生离心力，使密度不同的物质沉淀. · 离心沉淀过程中，需要部分的少量试剂会在离心力的作用下很容易的在试管中沉降. · 运转过程中，应该小心操作，避免试管、离心管等的损坏. · 液体不能超过试管的一半位置，防止液体在运转过程中溢出． · 试管放入前应擦去外部残余液体，放置离心管极其内部转子等部件腐蚀． · 离心管插入转子的数量必须成对，并且相对放置，已保证运转过程中的稳定性 · 两个离心管中，所放置物质的重量必须相同． · 打开盖子时，如果转子还未停止旋转，不要视图取出试管，一定要等转子停止后才能去取出实验物． · 不用的试管一定要记得从离心管中取出，余留的试管极易造成离心机事故的发生． · 保护管中的试管在离心机运转过程中破碎时，应立即停止离心机工作，将破碎的试管碎片和液体从机器内清理干净．

在CT图像定量分析的过程中，相信大家都遇到过这样的情况：很难找到一个合适的阈值来分割我们要分析的对象。尤其是对于样品中的细微结构而言，由于没有足够高的分辨率来表征，造成其灰度要低于正常值，局部衬度降低。这就对我们的阈值选取、个体分割造成了非常大的困难，尤其是动辄几百兆，几个G的三维CT数据。所以在进行阈值分割之前，各种滤波工具就被我们拿来强化对象，弱化背景噪音，以期能够得到一个更准确的结果

样品前处理是指样品的制备和对样品中的待测组分进行提取、净化和浓缩的过程。样品前处理的目的是消除基质干扰、保护仪器、提高检测方法灵敏度、选择性、准确度、精密度。

本文总结了用户使用分光光度计测量样品时，经常遇到的一些问题，并分析了这些问题出现的原因，再针对每种原因给出了相应的解决办法。

材料在低温下常常表现出“奇异”的力学行为。获得材料在低温区各温度点的力学性能数据才能认识材料随温度变化的力学行为，进而更深入地揭示材料力学行为中的规律。精确测量材料在低温环境中的力学性能，对材料、力学和物理等基础研究和高精技术应用发展具有重要的意义。要进行低温下的材料力学行为研究，材料低温力学性能测试系统是必不可少的重要装备之一。如2014年9月，Science 杂志报道了 CrMnFeCoNi 高熵合金优异的低温力学性能（A fracture-resistant high-entropy alloy for cryogenic applications，Science 2014: Vol. 345 no. 6201 pp. 1153-1158 DOI: 10.1126/science.1254581），此项成果的取得，离不开美国劳伦斯-伯克利国家实验室低温力学性能测试装备的支持。 中国科学院理化技术研究所经过二十多年的研制和积累，开发出低温综合力学测试系统，此系统能进行材料低温环境（4.2K—300K（-269℃—室温）温区内任意温度）的力学性能测试，包括：拉伸、压缩、弯曲、剪切、扭转、断裂韧度等静态力学性能；疲劳裂纹扩展速率；拉拉疲劳、拉压疲劳、压压疲劳、扭转疲劳、拉（压）扭复合疲劳等疲劳性能测试。同时，还包括超导材料（低温超导线材、高温超导带材）加载电流时的力学性能、电学性能测试；非标试样和零部件的低温力学性能测试。

蔡司最新推出的Smartzoom 5智能3D数码显微镜是一款为工业质量控制领域的客户提供的一项全新解决方案的显微镜。可对样品进行三维成像，数码变倍及光学变焦，让数码显微镜实现了无极连续变倍，并可快速便捷地对样品进行二维、三维的观察和测量，适用于日常检测与失效分析。 蔡司3D数码显微镜特点： 1.全自动无极变焦，可连续变倍，用户可在任意倍数下准确测量 2.全触摸屏操作，无论是调焦、变倍、移动样品都可通过触摸屏实现，方便快捷。 3.镜头可倾斜观察，贴近客户应用。 4.集成式LED光源，光源集成到物镜中，可同时使用环形光和同轴光，极大的扩展各种应用。 5.大载物台设计，可放置大和重的样品，行程达130X100mm。 6.智能化设计与操作，特别设计的管理员模式与操作者模式，操作者只需根据管理员设计的程序操作即可，避免出错并提高工作效率，应用报告也自动生成。

在当今轻量化需求的汽车工业里，铝合金材料得到广泛的应用。然而，为提高铝合金的机械性能和耐磨性，硬质氧化层的使用变的越来越普遍。 硬质氧化层一般有30-80μm厚，有的甚至只有几微米。对于这类涂层，传统的依赖于用光学方式查看压痕大小从而测算硬度的方法（如显微维氏硬度）已达到其测量极限。仪器化压痕法是替代传统测量方式的最佳方法，不仅能够去衡量其塑性变形性能（HV），还能够测量一系列决定涂层质量优劣的其它机械性能。用仪器化压痕法，即便是非常薄的阳极氧化层，也不用担心基材对测量氧化层性能时的影响。

In current wing design, multiple flaps are incorporated into the trailing edge to allow mixing of high and low pressure sides to reduce flow separation. These flaps reduce the efficiency by adding weight and complexity to the aircraft. A single hinged flap would reduce these inefficiencies but is more susceptible to flow separation. Active flow control is a means by which the fluid flow over a body is deliberately altered and can be altered such that it becomes less likely to separate from the object. By energizing the flow, the degree of separation of the flow can be controlled, and this inherently controls lift. Dielectric barrier discharge (DBD) plasma actuators are a form of active flow control. These actuators are created by asymmetrically aligning two electrodes and adding a dielectric layer between the electrodes. When the electrodes are electrically connected, ionized air (plasma) travels from the exposed electrode towards the covered electrode. Collisions occur between the plasma and neutral air over the body, and momentum is transferred to the neutral air, effectively energizing it. The purpose of this study is to examine the lift enhancement and flow control authority that multiple DBD plasma actuators have on a high-lift airfoil when compared to the flow exhibited by noncontrolled and single DBD plasma actuator controlled cases. Electrodes were mounted onto a simplified NASA Energy Efficient Transport airfoil near the flap. The airfoil was tested in a closed, recirculating wind tunnel operating at a Reynolds number of 240,000, 20° flap deflection angle and 0° degree angle of incidence. The actuators were independently powered in order to determine the most effective input parameters. Using multiple actuators operated in-phase has increased the lift and has delayed flow separation on the trailing edge flap when compared to baseline and single actuation cases.

Turbulence of the round jet has been assessed using invariants of the velocity gradient tensor. Experimental data, obtained using Tomographic Particle Image Velocimetry (Tomo-PIV), using four PCO-4000 cameras with 11 megapixel resolution, is presented for a seeded free air jet, operating in the turbulent regime and the Re number based on the diameter of the nozzle is 10000. Using the acquired 3-D velocity fields, the local statistical and geometrical structure of three-dimensional turbulent flow can be described by properties of the velocity gradient tensor. The invariants of the velocity gradient (R and Q), rate-of-strain ( Rs andQs ), and rate-of-rotation (Qw ) tensors are analyzed across the turbulent expanding regions at different distances from the nozzle outlet. More specifically, the JPDF of invariants is computed, which allows a detailed statistical characterization of the dynamics, geometry and topology of the flow during the entrainment process. It should be noted that the results obtained are indicative of the preliminary work in this area.

微纳米气泡因其自身体积小、比表面积大、自身增压溶解等特点，具有广泛的应用价值。但微纳米气泡受气泡发生条件的影响很大，需要依靠准确的检测方法去优化气泡发生条件，检测微纳米气泡的性质。本文借助动态图像法和纳米颗粒跟踪分析技术，分别检测了微米气泡和纳米气泡：通过动态图像法，测得微米气泡的粒径分布、气泡数量、球形度等信息，用于表征、鉴别微米气泡；通过纳米颗粒跟踪分析技术，测得纳米气泡的粒径分布、浓度、电位等信息，用于全面表征纳米气泡的性质。

比热容，是物质的一项基本物理特性，DSC法因为具有操作简便，测试快速等特点，已经成为比热容测试的一个常用方法。但同时，比热容的测试也一直是DSC的难点之一。与相变热、反应热等热量相比，物质的比热产生的DSC信号通常是很微弱的，在DSC图曲线上一般反映为“基线漂移”。 卡尔维式三维热流传感器中，热电偶阵列呈三维排列，完全包围样品空间，全方位探测样品与环境间的热交换。 -高灵敏度，比DSC的灵敏度高一至两个数量级。 -高效率，完全搜集样品的吸放热，效率高达95%以上 -电标定，一劳永逸：标定结果适用于任何样品的任何反应，包括比热容测试 -样品适应性，适用于固体，粉末，液体及多相混合物等各种形态的样品测试。 各种样品的比热容测试准确度优于98%。

Over the past twelve years, two-dimensional and stereoscopic particle image velocimetry (PIV) techniques have been used to obtain detailed measurements of the thermal and transport properties of the microparticle component of dusty plasma systems. This letter reports on an extension of these techniques to obtain a volumetric, three-dimensional velocity vector measurement using tomographic PIV. Initial measurements using the tomographic PIV diagnostic are presented.

Despite rapid advancements in the patient-specific hemodynamic analysis of systemic arterial anatomies, limited attention has been given to the characterization of major venous flow components, such as the hepatic venous confluence. A detailed investigation of hepatic flow structures is essential to better understand the origin of characteristic abnormal venous flow patterns observed in patients with cardiovascular venous disease. The present study incorporates transparent rapid-prototype replicas of two pediatric hepatic venous confluence anatomies and two-component particle image velocimetry to investigate the primary flow structures influencing the inferior vena cava outflow. Novel jet flow regimes are reported at physiologically relevant mean venous conditions. The sensitivity of fluid unsteadiness and hydraulic resistance to multiple-inlet flow regimes is documented. Pressure drop measurements, jet flow characterization, and blood damage assessments are also performed. Results indicate that the orientation of the inlets significantly influences the major unsteady flow structures and power loss characteristics of this complex venous flow junction. Compared to out-of-plane arranged inlet vessel configuration, the internal flow field observed in planar inlet configurations was less sensitive to the venous inlet flow split. Under pathological flow conditions, the effective pressure drop increased as much as 77% compared to the healthy flow state. Experimental flow field results presented here can serve as a benchmark case for the surgical optimization of complex anatomical confluences including visceral hemodynamics as well as for the experimental validation of high-resolution computational fluid dynamics solvers applied to anatomical confluences with multiple inlets and outlets.

实验室QM是非常复杂而且对外是不“透明”一个系统。在如今科技高速发展的今天QM实验室对于一个正规厂家来说是必须的，本文详细介绍了如何系统化建立QM实验室的流程以及各种标准在实验室标准化中起到的作用。FRITSCH公司各种仪器在QM实验室中的应用举例。 具体的研磨粉碎实验方法及相关实验数据，欢迎您来电话与北京飞驰科学仪器有限公司取得联系。

GATAN 第二代精密刻蚀镀膜仪(PECS TMII)是一款桌面型宽束氩离子抛光及镀膜设备。对于同一个样品，可在同一真空环境下完成抛光及镀膜。PECSII是一款完全独立、结构紧凑的台式设备。采用两个宽束氩离子源对样品表面进行抛光，去除损伤层，从而得到高质量样品，用于在SEM，光镜或者 扫 描 探 针 显 微 镜 上 进 行 成 像 、 EDS、 EBSD、 CL、 EBIC或其它分析。

The three dimensional near wake flow topology behind a blunt trailing edge flat plate is investigated for a Reynolds number range varying from 500 to 4.6x104 using a combination of flow visualization, numerical simulations and experiments. The secondary wake instabilities are identified using vorticity maps from CFD and performing Proper Orthogonal Decomposition (POD) on PIV data from experiments to identify the underlying dominant coherent structures. These structures are found to appear at a spanwise spacing ranging from 2.2 to 4.8. At higher Reynolds numbers the secondary wake instabilities appear to be unsteady in space and time.

PIV- and LDV- measurements of baroclinic wave interactions in a thermally driven rotating annulus U. Harlander, Th.v. Larcher, K. Alexandrov, and C. Egbers Department of Aerodynamics and Fluid Mechanics, BTU Cottbus October 7, 2008 EULAG 1 Experimental setup 2 Equations and boundary conditions 3 Regime Transitions 4 Data processing 5 Recent results Frame co-rotating with cylinder Frame co-rotating with wave LDA observations 6 Numerical simulations with EULAG 7 Outlook

This paper highlights the influence of contact line (pinning) forces on the mobility of dry bubbles in microchannels. Bubbles moving at velocities less than the dewetting velocity of liquid on the surface are essentially dry, meaning that there is no thin liquid film around the bubbles. For these “dry” bubbles, contact line forces and a possible capillary pressure gradient induced by pinning act on the bubbles and resist motion. Without sufficient driving force (e.g. external pressure) a dry bubble is brought to stagnation. For the first time, a bipartite theoretical model that estimates the required pressure difference across the length of stagnant bubbles with concave and convex back interfaces to overcome the contact line forces and stimulate motion is proposed. To validate our theory, the pressure required to move a single dry bubble in square microchannels exhibiting contact angle hysteresis has been measured. The working fluid was deionized water. The experiments have been conducted on coated glass channels with different surface hydrophilicities that resulted in concave and convex back interfaces for the bubbles. The experimental results were in agreement with the model’s predictions for square channels. The predictions of the concave and convex back models were within 19% and 27% of the experimental measurements, respectively.

The emission of oxides of nitrogen, or NOx, by aircraft is an international concern. NOxcontributes to smog in the lower atmosphere and destroys ozone in the stratosphere. To reduce NOxand other harmful emissions, NASA has developed Multipoint Lean-Direct Injection (MP-LDI). To determine the effectiveness of MP-LDI and its potential for future commercial use, particle image velocimetry (PIV) obtains velocity data which is important for setting the inlet and boundary conditions needed for validating computational fluid dynamics codes such as the National Combustor Code (NCC).

Thermo ScientificTM DionexTM ChromeleonTM 7 色谱数据系统 (CDS) 软件采用CobraTM 峰检测算 法、SmartPeaksTM 积分助手和动态交互数据处理，可节省您的宝贵时间。Cobra 检测算法可准确地检测峰起始和终止的时间，并正确地确定峰基线，无需输入一系列检测参数。独一无二的SmartPeaks 积分助手帮助用户快速、直观地确定基线。Chromeleon 7 CDS 帮助用户快速完成从样品到结果的过程，从而全面提高实验室的工作效率。

伯东公司电厂使用氦质谱检漏仪主要是对汽轮机内部真空系统的检漏，还有冷凝罐的检漏，由于每一个环节如果有泄漏的话都会增加生产成本，所以电厂检漏在实际生产中是非常重要的。

近年来，随着科技的发展和材料尺寸的不断缩小，扫描电镜（SEM）已经成为一种非常有价值的表征方法。SEM作为一种通用的工具，方便用户可以对各种各样的材料进行多种不同类型的分析。为获得更好的结果，用户应该仔细设定SEM参数。其中一个设置是束斑直径，即照射在样品上的电子束直径。在这篇博客中，阐述了如何在SEM中调整束斑直径，以及如何在高分辨率成像和大束流之间实现平衡，以获得最佳结果。

We report experimental measurements of inertial waves generated by an oscillating cylinder in a rotating fluid. The two-dimensional wave takes place in a stationary cross-shaped wavepacket. Velocity and vorticity fields in a vertical plane normal to the wavemaker are measured by a corotating particle image velocimetry system. The viscous spreading of the wave beam and the associated decay of the velocity and vorticity envelopes are characterized. They are found in good agreement with the similarity solution of a linear viscous theory, derived under a quasiparallel assumption similar to the classical analysis of Thomas and Stevenson “A similarity solution for viscous internal waves,”

电子显微镜已经成为表征各种材料的有力工具。 它的多功能性和极高的空间分辨率使其成为许多应用中非常有价值的工具。 其中，两种主要的电子显微镜是透射电子显微镜（TEM）和扫描电子显微镜（SEM）。 在这篇博客中，将简要描述他们的相似点和不同点。  

In this report we present the methodology we are using in the AMI group to compare optic flow estimation methods in the context of the FLUID Specific Targeted Research Project - Contract No 513633 founded by the CEE. The main goal of this report is to try to unify comparison criteria between the different parnerts in order to share information and conclusions. We think that it is one of the topics we have to address in Las Palmas Meeting December next. In order to describe the methodology we use, we divide it in five steps: 1. We choose a number of optic flow estimation methods 2. We choose an image sequence dataset to apply the methods. 3. We apply the methods and we store the results in a ASCII file using an standard format 4. We define a number of statistics to compare the methods (we use the ASCII files as basic information to compare). 5. We compute the statistics for each pair of methods and we generate tables with the information. To help result interpretation we use arrow images and in the case we know the optic flow groundtruth we generate image to provide the information about what method perform better in the different areas of the image. To illustrate this approach and to fit ideas we present the results of this approach in a particular image sequence provided by LaVision in sections from 1.1 to 1.4. Then, in section 2 we remark some of the difficulties we have found in our work, which should be discussed in order to be able to compare results provided by all the partners of the FLUID project.