其他检测

大部分单壁碳纳米管(SWNTs)的研究聚焦于单管，而对于多管束的研究甚少。根据新的研究结果表明，可以通过检测SWNTs激子研究单管和多管束的电子性质。因此利用HORIBA Scientific（Jobin Yvon光谱技术）设计生产的Nanolog模块式近红外荧光光谱仪，研究SWNTs管束间FRET的光致发光光谱，从而获得SWNT管束的电子性质。

Water droplets are introduced via four spray nozzles, with the resulting size distribution being quite broad ( ¯ d = 22 μm, ¾d = 13 μm). Downstream, a Phase Doppler Interferometer (PDI) (15) simultaneously measures the diameter (di), downstream speed (vi), and arrival time (ti) of any droplets that traverse its view volume (which has a linear dimension of roughly 150 μm). The PDI system was built and calibrated by Artium Technologies, Inc. and is designed for in situ measurement, such that the instrument does not disturb the flow through the measurement volume when aligned parallel to the mean flow.

为了彻底深入了解防护热板法导热系数测试过程中国际标准方法ISO 8302和A-S-T-M C177对热稳定测试间隔时间的界定，本文从热时间常数的定义着手，进行了详细的推导，揭示出热时间常数的物理意义以及防护热板法热稳定性判断的整个详细过程，通过此详细过程的结果指出国际标准ISO 8302和国家标准中存GB/T 10294在的错误，并对国际标准中的热时间常数经验公式进行了修正，最后采用MapleSim仿真模拟计算结果验证了修正公式的正确性。

Dialysis is a method of removing toxic substances (impuritities or wastes) from the blood when the kidneys are unable to do so. ICP-OES is particularly suitable to measure the dialysis solutions for the high accuracy analysis of Na, K,Ca, Mg and Cl. This Application Note presents the preparation and analysis results of two dialysis samples.

1、光谱分类及原子光谱分析方法有哪些？ 2、什么是AES？常见的AES仪器有哪些？ 3、光谱仪定性和定量计算原理是什么？ 4、直读光谱仪器的误差来源有哪些？ 5、直读光谱仪有哪些种类？

Abstract—In-cylinder flow field structure in an internal combustion (I.C) engine has a major influence on the combustion, emission and performance characteristics. Fluid enters the combustion chamber of an I.C engine through the intake manifold with high velocity. Then the kinetic energy of the fluid resulting in turbulence causes rapid mixing of fuel and air, if the fuel is injected directly into the cylinder. With optimal turbulence, better mixing of fuel and air is possible which leads to effective combustion. A good knowledge of the flow field inside the cylinder of an I.C engine is very much essential for optimization of the design of the combustion chamber for better performance especially in modern I.C engines like gasoline direct injection (GDI), homogeneous charge compression ignition (HCCI) engines.The main objective of this work is to study the incylinder fluid flow field characteristics of a single-cylinder engine to see the effect of intake manifold inclination at equivalent rated engine speed using Particle Image Velocimetry (PIV) under various static intake valve lift conditions. To facilitate the PIV experiments, the metal cylinder of the engine was replaced by a transparent one. For every operating test condition, 50 image pairs were captured and processed using DAVIS software. From the results, it is seen that the in-cylinder flow structure is greatly influenced by the intake manifold inclinations irrespective of intake valve lift. Maximum Turbulent Kinetic Energy (TKE) was highest at full intake valve lift irrespective of the inclination. Also, the maximum TKE was the highest for 600 intake manifold inclination compared to other inclinations irrespective of the intake valve lift at equivalent rated engine speed. Finally, it is concluding that the analysis carried in this work is useful in predicting the flow and inturn optimizing combustion chamber of modern I.C engines.

We have studied the flow induced by a macroscopic spherical particle settling in a Laponite suspension that exhibits a yield stress, thixotropy, and shear thinning. We show that the fluid thixotropy
or aging induces an increase with time of both the apparent yield stress and shear-thinning properties but also a breaking of the flow fore-aft symmetry predicted in Hershel-Bulkley fluids
yield-stress, shear-thinning fluids with no thixotropy. We have also varied the stress exerted by the particles on the fluid by using particles of different densities. Although the stresses exerted by the particles are of the same order of magnitude, the velocity field presents utterly different features: whereas the flow around the lighter particle shows a confinement similar to the one observed in shear-thinning fluids, the wake of the heavier particle is characterized by an upward motion of the fluid
“negative wake”, whatever the fluid’s age. We compare the features of this negative wake to the one observed in viscoelastic shear-thinning fluids
polymeric or micelle solutions. Although the flows around the two particles strongly differ, their settling behaviors display no apparent difference which constitutes an intriguing result and evidences the complexity of the dependence of the drag factor on flow field.

Tomographic particle image velocimetry is a 3D PIV technique based on the illumination, recording, reconstruction and analysis of tracer-particle motion within a three-dimensional measurement volume. The recently developed technique makes use of several simultaneous views of the illuminated particles, typically 4, and their three-dimensional reconstruction as a light-intensity distribution by means of optical tomography. The reconstruction is performed with the MART algorithm (multiplicative algebraic reconstruction technique), yielding a 3D distribution of light intensity discretized over an array of voxels. The reconstructed tomogram pair is then analyzed by means of 3D crosscorrelation with an iterative multigrid volume-deformation technique, returning the three-component velocity vector distribution over the measurement volume. The implementation of the tomographic technique in time-resolved mode by means of high repetition rate PIV hardware has the capability to yield 4D velocity information. The first part of the chapter describes the operation principles and gives a detailed assessment of the tomographic reconstruction algorithm performance based upon a computer-simulated experiment. The second part of the chapter proposes four applications on two flow cases: 1. the transitional wake behind a circular cylinder; 2. the turbulent boundary layer developing over a flat plate. For the first case, experiments in air at ReD = 2700 are described together with the experimental assessment of the tomographic reconstruction accuracy.

Increasingly smaller electronics requires improvement in performance of cooling systems to keep it operating reliably. We present herein a novel experimental study of convective heat transfer in serpentine microchannels with segmented liquid–liquid emulsions. It is demonstrated that this concept yields significant Nusselt number enhancement in microchannel heat sinks compared to that obtained using single phase liquid cooling. Laser Induced Fluorescence (LIF) is employed to measure temperature of the coolant with and without droplets, and micro-PIV is used to determine velocity field. For the segmented flow, up to four-fold increase of the Nusselt number was observed compared to pure water flow.

An experimental study has been conducted to study the effect of a swirling crossflow on transversely injected liquid jets. In-house designed axial swirlers with vane exit angles of 30°, 45° and 60° were used to generate the swirling crossflow. Laser Doppler Velocimetry (LDV) results indicate that the axial (Ux) and the tangential (Uθ) components of the crossflow velocity decrease with increasing radial distance from the center. Also, flow angle (ψ) of the crossflow is lesser than the swirler vane exit angle indicating that the swirlers did not impart sufficient tangential momentum for the flow to be parallel to the vanes at swirler exit. The deficit in flow angle increased with swirler angle. Water jets were injected from a 0.5 mm diameter orifice located on a cylindrical centerbody that protruded through the hub of the swirler. Particle Image Velocimetry (PIV) was used to study the behavior of the jets. PIV measurements were conducted in multiple cross-sectional and streamwise planes. Mie-Scattering images were col-lated to create three-dimensional representation of the jet plume, which was used to study penetration. In cylindrical coordinate system, the penetration can be described in terms of radial and “circumferential” penetration, where cir-cumferential penetration is defined as the difference in the circumferential displacement of the jet and the crossflow over the same streamwise displacement. Increasing the momentum flux ratio (q) resulted in a higher radial penetra-tion. Increasing the swirl angle reduced radial penetration and increased circumferential penetration. PIV results of the cross-sectional and streamwise planes each yielded two velocity components which were merged to obtain three-dimensional droplet velocity distribution. The three-dimensional velocity distribution yielded further insight into the evolution of the jet plume

扫描电镜检测是材料微观形貌观察必不可少的研究手段，但水凝胶材料由于含有大量水分或有机溶剂，无法直接放入电镜中观察。电镜工作需要维持高真空环境，而水分在真空中会迅速挥发，导致图像异常甚至电镜故障。因此，对于水凝胶样品，通常需要进行冷冻干燥处理，将水分去除后再进行拍摄。

We present an experimental study of the dynamics of a plume generated from a small heat source in a high Prandtl number fluid with a strongly temperaturedependent viscosity. The velocity field was determined with particle image velocimetry, while the temperature field was measured using differential interferometry and thermochromic liquid crystals. The combination of these different techniques run simultaneously allows us to identify the different stages of plume development, and to compare the positions of key-features of the velocity field (centers of rotation, maximum vorticity locations, stagnation points) respective to the plume thermal anomaly, for Prandtl numbers greater than 103. We further show that the thermal structure of the plume stem is well predicted by the constant viscosity model of Batchelor (Q J R Met Soc 80: 339–358, 1954) for viscosity ratios up to 50. 1 Introduction

对于一个具有综合分析能力的高水平电镜室，样品制备技术非常重要，这是扫描电镜充分发挥功能的前提。本文简述了扫描电镜和微区成分分析的样品制备知识和方法，涉及样品的镶嵌、清洁、磨抛以及相应的制备设备等方面，对于样品制备常见问题进行了简略分析。

随着转速的升高，在同样的转速下（400RPM），标准玻璃瓶会产生明显的空气穴；带有扰流板的瓶体涡流形成的空气穴很小。从图中可以看出，标准瓶的空气穴大，液体成规律性旋转，圆周速度快，扰流效果很差；带扰流板的瓶子相比标准瓶空气穴很小，液体在运动过程中因为扰流板的阻挡，内部涡流明显，混合效果比标准瓶更好

The unsteady lift generated by the flow of turbulence over the trailing edge of an airfoil can be an effective source of dipole sound. The objective of the present research was to experimentally measure the velocity field behind an asymmetric 45 degree beveled trailing edge in order to develop an understanding of the flow mechanisms responsible for the generation of trailing edge noise. Particle Image Velocimetry (PIV) data were acquired in the near wake region of the trailing edge at a chord Reynolds number of 1.9x106. The time averaged velocity statistics are indicative of a wake flow containing semi-periodic vortex shedding. These large scale shedding motions are commonly responsible for the tonal noise produced by the trailing edge. A phase average decomposition of the velocity field with respect to this shedding process was utilized to separate the small scale turbulent motions responsible for broadband sound production. This analysis has shown that the characteristics of the small scale turbulence are dependent on the phase of the vortex shedding process.

德国BMT 波纹度WSA 测试，波纹度WSA测试仪可分为手动测试仪和自动测试仪。软件可进行数据分析。

ASAP2020化学吸附仪可应用于许多不同的分析。其中，2020可以对担载金属的催化剂进行氢吸附分析。本文中所使用的样品是5% wt.钯/活性炭。在进行化学吸附的过程中，H2分子间的化学键发生解离，单个的H原子与催化剂表面的钯原子形成化学键1。仪器所测试的是一定压力下的金属表面氢吸附量。本文中主要研究了从0.01 mmHg到500 mmHg压力范围内的氢吸附量。

The analysis of the flow field inside hydraulic valves has become in the last few years a very important issue to be addressed in order to optimize the spool shapes and to obtain the desired flow metering characteristics. The Fluid-Power research unit of the Polytechnic of Bari realized many works dealing with the Computational Fluid Dynamics (CFD) analysis of directional control valves. Experimental measurements concerning discharged flow rate and needed driving force values have been performed in order to validate the numerical results, but the validation of CFD results has been limited, in the past, only to the global fluid dynamic response of the valve and not to the local flow conditions. In order to provide the flow field inside the valve through PIV (Particle Image Velocimetry) measurements, a valve model, equipped with a great optical access, has been realized. The scaled model has been realized according to the fluid dynamic similarity laws in order to use a fluid different from the oil (water) and to increase the dimensions of the valve. In particular, the realized model has a circumferential development useful to acquire important data about the circumferential flows and their effects on the global flow rate crossing the valve. The experimental results show that the velocity profiles in the metering sections are strongly influenced by the three-dimensional effects of the flow, confirming the results obtained numerically in previous works.

使用紫外可见分光光度计可以在不接触、不破坏的情况下简单地进行测定。本次对使用紫外可见分光光度计可以测试的紫外可见波长范围的膜厚进行了研究

The idea of manipulating flow to change its characteristics is over a century old. Manipulating instabilities of a jet to increase its mixing and to reduce its radiated noise started in the 1970s. While the effort has been successful in low-speed and low Reynolds number jets, available actuators’ capabilities in terms of their amplitude, bandwidth, and phasing have fallen short in control of high-speed and high Reynolds number jets of practical interest. Localized arc filament plasma actuators have recently been developed and extensively used at Gas Dynamics and Turbulence Laboratory (GDTL) for control of highspeed and high Reynolds number jets. While the technique has been quite successful and is very promising, all the work up to this point had been carried out using small high subsonic and low supersonic jets from a 2.54 cm diameter nozzle exit with a Reynolds number of about a million. The preliminary work reported in this paper is a first attempt to evaluate the scalability of the technique.

Within the framework of an investigation into valve operating strategies for homogeneous charge direct injection spark ignition engines under part load conditions this paper discusses the in-cylinder flow fields developed by running an optical engine with an early inlet valve closing strategy with a lift of 3.9 mm that produces 3bar IMEP at 3500 rpm under firing conditions. The experimental facilities are similar to previous work but measurement technique has been optimized with the significant aspect of this work being that the flow fields were determined in three vertical planes and one horizontal plane to highlight the three dimensional and the highly cyclic nature of the flow. These characteristics have significant impact on the application of the PIV technique and data processing to ensure a high degree of confidence in the flow fields generated. The time varying nature of this three dimensional flow field is discussed and how it impacts on the PIV measurement technique particularly as regards data acquisition and data processing. The true extent of the complex three dimensional flow field is readily seen and that, even though the combustion chamber geometry is symmetrical, the swirl flow field is not. The main features of the vertical flow structure are described over a crankangle period from 90oCA to 120oCA which highlight the dominant feature as being a wall jet flow which interacts with the piston crown to generate a strong reverse tumble flow.

Two-phase annular flow is commonly used in both commercial and industrial heat transfer; however, we do not yet possess a thorough understanding of the nature of the fluid. Most analytical annular two-phase models are based on a relationship between the liquid film thickness, liquid film mass flux, and the axial pressure gradient or interfacial shear stress. The film thickness calculated from these models can then be utilized to determine the heat transfer coefficient of the flow. Although they are specific to certain flow regimes and fluids, empirical models remain more accurate than these analytical models. The key to understanding these flows lies with the liquid film. Therefore, to better understand the pressure drop and heat transfer of annular two-phase flow, this study involves the development of local, liquid velocity measurement techniques and their application to horizontal, wavy-annular two-phase flow. Two techniques, Bubble Streak Tracking (BST) and Thin Film Particle Image Velocimetry (TFPIV), have been developed in this study. Utilizing naturally occurring bubbles within the liquid film, the BST technique determines the liquid velocity by measuring reflected light streaks from the bubbles. A three-colored LED array creates directionally unambiguous streaks, while a strobe illuminates interfacial features that affect the liquid velocity. The TFPIV technique applies a typical micro-PIV system to a macroscopic flow with the addition of a non-trivial image processing algorithm. This algorithm successfully overcomes the image noise that occurs when applying PIV to a two-phase, thin film. Although difficulties arise when processing the BST data, the results of the BST and TFPIV methods are comparable, making BST an economical alternative to TFPIV for calculating liquid film velocities.

Along with the rapid growth of research of microfluidics, monitoring and understanding micro flow behavior is a challenge for researchers. Particle Image Velocimetry (PIV), a powerful tool that makes flow visible, was extended to microscale by Santiago et al. 1998. In this paper, we presented the micro Particle Image Velocimetry (μPIV) system at Nanyang Technological University (NTU), its calibration and characterizations of microfluidic devices using μPIV. Since the fully developed microchannel flow has been well investigated, it is suitable to calibrate the measurements of μPIV. In our experiment, an in-channel microdispenser fabricated on printed circuit board is used to form a microchannel. A syringe pump forces water that contains fluorescent particles. The flow field is obtained by μPIV. At the same time, a three-dimensional model with ANSYS/FLOTRAN was used. The comparison between the two results demonstrates that our μPIV system works well. Furthermore we use this system to characterize a Tesla valve - a non-moving part valve. The valve consists of a fluid channel structure that has rectification property, which favors forward flow while hampers reverse flow. The velocity fields are also validated by ANSYS/FLOTRAN.

The experimental program that is being conducted at the Matched Index-of-Refraction (MIR) Flow Facility at Idaho National Laboratory (INL) to obtain benchmark data on measurements of flow phenomena in a scaled model of the lower plenum of a typical prismatic gas-cooled reactor (GCR) using 3-D Particle Image Velocimetry (PIV) is presented. A detailed description of the model, scaling, the experimental facility, 3-D PIV system, measurement uncertainties, experimental procedures and samples of the data sets that have been obtained are included. Samples of the data set that are presented include mean-velocity-field and turbulence data in an approximately 1:7 scale model of a region of the lower plenum. This experiment has been selected as the first Standard Problem endorsed by the Generation IV International Forum. Results concentrate on the region of the lower plenum near its far reflector wall (away from the outlet duct). Inlet jet Reynolds numbers (based on the jet diameter and the time-mean flow rate) are approximately 4,300 and 12,400. The measurements reveal undeveloped, non-uniform flow in the inlet jet ducts and complicated flow patterns in the modeled lower plenum. Data include three-dimensional vector plots, data displays along the coordinate planes (slices) and charts that describe the component flows at specific regions in the model. Information on inlet flow is also presented.

气相色谱仪启动后不久或色谱柱更换后不久，噪声是不可避免的，这是正常现象。噪声过大是指比正常的标准高得多的噪声或某些不正常的突变。发现噪声过大时，请先检查气相色谱仪和积分仪使用的电网电源是否有异常波动或突变，特别是在同一电网电源上接有大功率装置时，更要注意。此外，请检查仪器的接地是否正确并且良好。

继承第一届评测活动的成功经验，第二届评测活动的目的是要在定量评价现有的PIV和PTV算法上更进一步。汲取前次教训，测试项目有所减少。内容更加专注于用PIV方法和PTV方法对湍流的处理以及评价不同算法和软件对不同类型相机拍摄图片的处理结果上。

本文采用图文并茂的方式介绍本室采用PE DRC-e型ICP-MS分析食品中重点关心的14种金属元素(Hg、Cd、Cr、Mn、Cu、Fe、Mn、Zn、Sr、I、Pb、Se、P和As等)方法，，该法为本室常规检测方法，每年大约有5000-10000件食品样品被检测；重点讨论了实验室用酸选择、检测过程中酸效应、盐效应、记忆效应，以及部分元素的光谱干扰等常见问题。有待完善中，请大家补充！ 一、装备 1.1 实验用酸 ICP-MS分析常用酸主要有HNO3, H2O2 和HF; 杂质较少的进口高纯酸由于其价格比较昂贵，亚沸蒸馏器产酸率较小，长期使用性价比较高。我们比较了国内电子级BV-3型（图1. 北京化学试剂研究所）和常见的优级纯（GR）硝酸、双氧水和氢氟酸中的杂质，见图2。

在实验室中，尤其是使用高压液相色谱法（HPLC）时，会将至少两种溶剂进行梯度混合，由此会导致气体因溶解度的差异而过量析出，残留在流道内无法排出，从而影响检测精度。其它类似的高、低压分析仪器也会因为流量、温度的波动而产生类似的现象。本文针对气泡形成的原因作了详细的分析，并探讨了当今通用的一些解决方案。

光源部分： （1）故障：钨灯不亮； 原因：钨灯灯丝烧断（此种原因几率最高）； 检查：钨灯两端有工作电压，但灯不亮；取下钨灯用万用表电阻档检测。处置：更换新钨灯； （2）故障：钨灯不亮； 原因：没有点灯电压； 检查：保险丝被熔断；

这是文章《使用等离子体制动器实现对高速高雷诺数喷射的流动和噪声控制》的第二部分。该文报道了在亚音速至跨音速区间进行的一系列实验结果。