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影响DSC分析结果的主要因素，TG分析的主要影响因素，影响仪器仪表差热分析的主要因素，差热分析操作简单，但在实际工作中往往发现同一试样在不同仪器上测量，或不同的人在同一仪器上测量，所得到的差热曲线结果有差异。峰的最高温度、形状、面积和峰值大小都会发生一定变化。其主要原因是因为热量与许多因素有关，传热情况比较复杂所造成的。一般说来，一是仪器，二是样品。虽然影响因素很多，但只要严格控制某种条件，仍可获得较好的重现性。

本文介绍了采用下落式量热计方法开发的一种温度范围为100～1000℃的材料比热容测量装置。由于绝热材料一般密度低、气孔率高、低导热系数和热容较小，所以绝热材料的比热容很难准确测量。通过此开发的测试设备，采用将被加热试样落入水中的下落法，可以很容易的进行绝热材料比热容测量，所得到的测量结果是从下落前试样温度与试样下落后水平衡温度之间的平均比热容。采用此测试设备对标准参考材料SRM 720人造蓝宝石进行了测试，测试结果与标准数据偏差小于±10%。对碳化硅耐火材料、岩棉、硅铝矾土硅石纤维、硅铝矾土硅石板、硅酸钙和二氧化硅玻璃等材料进行了测试。

本文通过对闪光法热扩散系数测试技术中实际闪光激励有限脉冲宽度的研究，认为可以有效的拓展闪光法的应用。通过对闪光法热性能测定仪中脉冲波形参数的确定和描述，经过一系列一维有限元模拟建立一个等效矩形波脉冲波形和一个通用曲线来对热扩散系数测量进行修正。通过七种激励脉冲波形宽度和三种材料的实际测试，验证了这种模拟方向修正的有效性。

We present in this paper a novel collaborative scheme dedicated to the measurement of velocity in fluid experimental flows through image sequences. The proposed technique combine the robustness of correlation techniques with the high density of global variational methods. It can be considered either as a reenforcement of fluid dedicated opticalflow methods towards robustness, or as an enhancement of correlation approachs towards dense information. This results in a technique that is robust under noise and outliers, while providing a dense motion field. The method was applied on synthetic images and on real experiments in turbulent flows carried out to allow a thorough comparison with a state of the art optical-flow and PIV methods.

高低温试验箱,高低温湿热试验箱,交变湿热试验箱,恒温恒湿箱等环境试验设备的安全运输方式 这些仪器设备因为都安装了制冷压缩机装置,因此我们包装上注明:精密仪器,不可倾斜.物流运输时,一定要使用专用的升降机或者叉车置放于车上或卸货,对于物流运输人员不按规定卸货造成的设备损坏,要按照相关的承运合同,物流公司要给予该设备的损坏程度的一定经济赔偿,同时我们还要与用户协商沟通,并及时补发货物给用户,尽量减少因货物损坏造成的时间耽搁. 用户签收货物时注意的事项: 1.对于送货上门的物流公司,买家收货人员首先要监督一下卸货情况,卸车后并检查一下外包装有无损坏,如发现外包装破损,请跟物流公司协商能否打开包装查看设备有无损坏,如果设备没有损坏的情况下,方可签收物流运单,如果发现运输损坏,请不要签收物流运单,及时致电给卖家,让卖家处理. 2.对于货到自提的用户,需要去物流站点去提货,提货前验收货物与送货上门的一致.

This paper presents a methodology to evaluate the stability of cockles in shallow estuaries for different hydrodynamic conditions. Two methodologies are proposed in order to determine the suitability of the different regions of the estuary for cockles. Considering the complexity of all the processes which determine the movement of cockles, the methodology proposed here is intended to be a first approach to the problem taking into account only hydrodynamic variables, although the inclusion of biological variables is being studied at the present time. The aim of this work is to stablish an objective criteria for comparing the stability of cockles in different parts of an estuary under different hydrodynamic conditions. In order to perform this analysis we have developed a cockle habitat model model which considers the hydraulic characteristics of cockles and the flow patterns in the estuary.

Thermo Scientific™Dionex™Chromeleon™7.2色谱数据系统（CDS）是第一款CDS 支持所有主要前端的质谱（MS）仪器控制和数据处理企业（客户/服务器）环境中的分离技术（GC，IC，LC）。 Chromeleon 7.2 CDS通过Thermo Scientific ISQ™单四极杆GC-MS的本地驱动程序提供完全控制系统和Thermo Scientific™TSQ™8000三重串联四极杆GC-MS / MS系统，包括调谐和仪器校准。

电子显微镜(SEM)和 X -射线电子能谱(XPS), 同时结合实验对其运用进行了详细的介绍和分析。 结果表明:SEM 和 XPS相结合应用于涂层分析, 可以很好地获得涂层形貌和结构的信息。

Laser-Induced Incandescence (LII) occurs when a high-energy pulsed laser beam encounters graphitic particulate matter particles like soot or carbon black. The particles absorb laser energy from the beam and see an increase in their internal energy, resulting in an increase of temperature. At the same time, the particles loose energy through heat transfer mechanisms. If the energy absorption rate is sufficiently high, particle temperature will rise to levels where significant incandescence (blackbody emission) can occur .Typically, Laser-Induced Incandescence produces 50ns to 1μs long light pulses at atmospheric pressure. So far, LII measurements had been restrained to conduction-dominated conditions, whereby signals are short-lived (less than one microsecond) and require sensitive nanosecond resolution instrumentation. This thesis introduces a novel LII – based measurement method performed under high vacuum conditions. The novelty of LII under vacuum resided in the fact that heat conduction away from the soot particle becomes negligible below 10-2 mbar and this constituted a step away from the typical situation, whereby laser absorption is followed by heat conduction from the particles to the surrounding medium. Instead, sublimation and radiative heat transfer would follow laser absorption. The consequence was the obtention of long-lived LII signals (up to 100 microseconds) and a large gain of photons (ranging between 50 to 300) emitted per primary soot particle during LII temperature decays. Furthermore, the refractive index function E(m) value could be determined directly from measured radiative temperature decays, with potentially an uncertainty of circa 7%, which outperformed current soot extinction measurements. In addition, for laser fluences below 0.06 J/cm2, a regime where only laser energy absorption and radiative heat transfer apply would be reached and LII signals became independent of particle size.

The wake behind a simpli¯ed model of a generic aircraft (the SWIM model) is measured in the Low Speed Low turbulence wind tunnel (LSL) at Delft University of Technology. Two measurement techniques have been used in order to qualitatively and quantitatively measure the wake, i.e. stereoscopic particle image velocimetry (Stereo PIV) and a 5 hole probe (5HP). Furthermore balance measurements have been carried out over a range of con¯gurations for later comparison purposes. The goal of the wake measurements is to give a comparison between the two measurement techniques. The 5HP measurements are processed using a windows based program called Pressure Field Visualisation. This program calculates vector ¯elds from the input pressure data and has several exporting options. The Stereo PIV measurements are correlated using DaVis 7.3 using a window size of 16 x 16 pixels with 50% overlap.

Dual particle image velocimetry (dual PIV) measurements have been performed to investigate the space–time correlations in two subsonic isothermal round jets at Mach numbers of 0.6 and 0.9. The correlation scales are analyzed along the centerline and in the shear-layer center over the first 11 jet diameters from the nozzle exit. To provide robust results over a wide range of flow conditions, these correlation scales are given in terms of their appropriate quantities, namely, the mean or rms velocity in reference to velocity and the momentum thickness or the half-velocity diameter in reference to length in the shear layer and on the jet axis, respectively. From these results, a discussion on the modeling of turbulence in jets is addressed. The self-similarity of some space correlation functions in the shear layer and on the jet axis is shown. Furthermore, far enough downstream in the shear layer, some of the ratios between the space and time scales are relatively close to the values expected in homogeneous and isotropic turbulence. It is also found that the ratio between the integral length and the time scales in the fixed frame is of the order of the local mean flow velocity. In the convected frame, the appropriate scaling factor is the rms velocity.

上海田枫在制冷设备方面拥有十几年的行业经验与技术，以先进的性能、质优价廉的设备、诚信的作风和贴心的服务赢得了客户的信任。田枫为大家讲解如何制定冻干曲线。

We report on spatially resolved simultaneous measurements of temperature and majority species concentrations along a line segment in a premixed laminar H2-air flame. The results are obtained from Raman and Rayleigh scattering by using a narrow-band KrF excimer laser and a spectrally and spatially resolving detector system that consists of a high-throughput spectrometer and a gated, intensified, two-dimensional CCD camera. The data presented here are integrated over 100 laser shots. Absolute density profiles of N2, 02, H20, and H2, as well as temperature profiles at various heights through the flame, are presented. A discussion of the required calibration procedures and a summary of the necessary spectroscopic background are also included in this paper.

所谓光致发光（Photoluminescence简称PL），是指物体依赖外界光源 进行照射，从而获得能量，产生激发导致发光的现象。也指物质吸收光子（或电磁波）后重新辐射出光子(或电磁波)的过程。光致发光过程包括荧光发光和磷光发光。

Polyolefins are polymers produced from olefins such as ethylene and/or propylene. Although polyolefins can be produced via different production methods, the gas-phase polymerization process based on fluidized bed reactor technology is the most important method for the production of polyethylene since the 1980’s and also polypropylene is increasingly produced via the gas-phase polymerization process. Although fluidized bed reactors have been employed for several decades in the chemical industry, quantitative information on solids motion and macroscopic circulation patterns is still incomplete.

T1000测温仪就是采用四线制铂电阻进行测温，测温精度高（0.01℃），稳定性好（3mk），配合B系列温度标准槽（温度波动度0.01℃）及标准铂电阻，可对工业级的热电阻、热电偶及热敏电阻等进行计量，已在多家温度计生产厂家使用。

激光粒度仪现在已经实现的准确性，在几年前是不可想象的。市面上最新版本的粒度仪，比起它的前身，拥有较小的偏差、更快的运作以及测量的准确性等优点。与以往的机型相比，“analysette 22”采用的图形软件加上多任务操作系统以及强大功能的计算机，使其拥有更高的可靠性和重现性。

This paper discusses the measurement of transparent particles and droplets from a few microns to mm in diameter with the Droplet Imaging Velocimeter and Sizer (DIVAS), a two-dimensional technique to measure particle size and velocity. Unlike Interferometric Laser Imaging for Droplet Sizing (ILIDS), DIVAS can measure sprays with realistic concentrations, size distributions from microns to millimeters, and non-spherical spray features. The measurement of particles with a broad range of diameters is discussed to illustrate the capability of DIVAS and signal analysis strategies are suggested to expand the measurement envelop and accuracy of the technique. DIVAS uses a Particle Imaging Velocimetry (PIV) configuration; that is, pulsed lasers illuminate the droplets in the measurement plane and CCD cameras collect the off-axis scattered light, thus yielding a small measurement volume and correspondingly a high number density measurement capability. Particle sizing is based on measuring the separation of cross-polarized glare points captured by two separate cameras.

摘 要： 葡萄糖（Dextrose），又称右旋糖，遇水易发生结晶，微溶于乙醛，不溶于乙醚和芳香烃。葡萄糖是生物代谢中的关键中间物质，食品工业用作甜味料（甜度约为蔗糖74%）。葡萄糖的粒径大小和形状可直接影响到食品添加剂的口感和保质期，由于其物质密度很低，通常的粒径分析方法不易得到准确的结果，在葡萄糖粉末中，加入气相二氧化硅作为分散剂，用RETSCH TECHNOLOGY公司的CAMSIZER粒径及形态分析仪进行粒径大小和形态的分析，可以得到准确而直观的结果。 Glucose（Dextrose）is easy to be crystallized and dissolve in the acetaldehyde while it is not to be dissolved in ether and arene. The glucose is a key intermediate relating to metabolism. it is used to be sweet flavor in food industry. The particle size and shape of glucose can influence the tasting of food and quality period. Because of its low density, it is very difficult to analysis it with sieve and laser instruments. Mixed with the gas-silicon and using CAMSIZER can help to get the correct results and images. 关键词：葡萄糖、气相二氧化硅、粒径、形态、CAMSIZER Key words：Dextrose, Gas phase silicon, particle size, shape, CAMSIZER

ACE Glass Inc. 开发了一种新型的使用双夹套的玻璃反应釜。除了常规使用的导热介质夹套，该反应釜还配置了一个可以抽真空的夹套。这个真空夹套层进一步防止了系统的散热损耗。该夹套的另外一个好处就是防止反应釜表面在低温状态的结霜现象，使用者可以在反应的整个过程中清楚地观察反应的进程。下面的图片是在夹套中冷媒温度在-55℃时的状况！请注意在真空夹套的表面没有结霜的现象。

A burner for investigating lean stratified premixed flames propagating in intense isotropic turbulence has been developed. Lean pre-mixtures of methane at different equivalence ratios are divided between two concentric co-flows to obtain annular stratification. Turbulence generators are used to control the level of turbulence intensity in the oncoming flow. A third annular weakly swirling air flow provides the flame stabilization mechanism. A fundamental characteristic is that flame stabilization does not rely on flow recirculation. The flames are maintained at a position where the local mass flux balances the burning rate, the result is a freely propagating turbulent flame front. The absence of physical surfaces in the vicinity of the flame provides free access for laser diagnostics. Stereoscopic Planar Image Velocimetry (SPIV) has been applied to obtain the three components of the instantaneous velocity vectors on a vertical plane above the burner outlet where the flames propagate. The instantaneous temperature fields have been determined through Laser Induced Rayleigh (LIRay) scattering. Planar Laser Induced Fluorescence (PLIF) on acetone has been used to calculate the average equivalence ratio distributions. Instantaneous turbulent burning velocities have been extracted from SPIV results, while flame curvature and flame thermal thickness values have been calculated using the instantaneous temperature fields. The probability distributions of these quantities have been compared considering the separate influence of equivalence ratio stratification and turbulence.

A novel method is introduced for increasing the accuracy and extending the dynamic range of time-resolved PIV. The approach extends the well-known concept of multiframe particle tracking velocimetry (PTV) to cross-correlation analysis employed by PIV. The working principle is based on the determination of fluid element trajectories by tracking their position across an image sequence. The fluid trajectory correlation (FTC) algorithm deals with the effect of trajectory curvature and non-uniform velocity during the considered time interval by allowing the motion within the trajectory to be nonlinear. In addition, the local image deformation accounts for the spatial velocity gradient and its change along the trajectory. The principle for reduction of the measurement error is threefold: by enlarging the temporal measurement interval, the relative error becomes smaller; secondly, the random error is reduced with the use of a least-squares polynomial fitting approach to the individual trajectory; and finally, the use of nonlinear fitting functions allows for a reduction in truncation errors. The evaluation of velocity proceeds then directly from the analytical derivatives of the least-squares functions. The principal features of this algorithm are compared with a single-pair iterative image deformation method through the use of synthetic image sequences depicting steady flows (solid body rotation and uniform motion), and with an application to an experimental data set of a submerged circular jet.

Electric field reversals in single and dual-frequency capacitively coupled radio frequency discharges are investigated in the collisionless (
1 Pa) and the collisonal (65 Pa) regimes. Phase resolved optical emission spectroscopy is used to measure the excitation of the neutral background gas caused by the field reversal during sheath collapse. The collisionless regime is investigated experimentally in asymmetric neon and hydrogen single frequency discharges operated at 13.56MHz in a GEC reference cell. The collisional regime is investigated experimentally in a symmetric industrial dual-frequency discharge operated at 1.937 and 27.118 MHz. The resulting spatio-temporal excitation profiles are compared with the results of a fluid sheath model in the single frequency case and a particle-in-cell/Monte Carlo simulation in the dual-frequency case. The results show that field reversals occur in both regimes. An analytical model gives an insight into the mechanisms causing the reversal of the electric field. In the dual-frequency case a qualitative comparison between the electric fields resulting from the PIC simulation and from the analytical model is performed. The field reversal seems to be caused by different mechanisms in the respective regimes. In the collisionless case it is caused by electron inertia, whereas in the collisional regime it is caused by a combination of the low mobility of electrons due to collisions and electron inertia. Finally, the field reversal during the sheath collapse seems to be a general source for energy gain of electrons in both single and dual-frequency discharges.

In the last years, several techniques have been developed and improved in such a way that it is possible to measure the three velocity components in a flow. Some techniques as Stereoscopic PIV or holographic PIV are well known. Others, like tomographic PIV started to develop more recently. Stereoscopic Particle Image Velocimetry (SPIV) or Tomographic PIV need a complex set-up, involving flow visualization with several cameras, and present important restrictions when applied to confined liquid flows. Others like Holographic PIV cannot be applied in flows with a high particle density. Here a new technique, called High Speed Digital Image Plane Holography has been developed for the measurement of the three velocity components in a complex geometry brain aneurysm model using a configuration similar to regular PIV. This was done by using a two cavity high speed laser, one double frame high speed camera and normal visualization. The two in-plane velocity components were obtained from the holograms reconstructed intensity distribution using a PIV analysis. The out-of plane component was obtained from the reconstructed phase differences using an interferometric method. Due to the laser short coherence length, a portable and compact system has been built in order to be able to the measure larger fluid areas.

We consider the effects of the mixing conditions at the nozzle, on the mixing in a circular impinging jet. Two situations are considered: the completely premixed tracer or a locally injected tracer. The local instantaneous concentration field is determined by using Planar Laser-Induced Fluorescence (PLIF) technique. The premixed injection variant reveals the mixing effects of the outer shear layer, while the local mixing approach helps in understanding how to utilize the local injection for controlling the mixing of a scalar in an impinging jet. The concentration statistics and the mixing properties indicated by concentration probability density function (PDF) with the two injection methods are presented. The results show the well-known structural features in the turbulent impinging jet, the nature of mixing varies significantly in different regions of the jet. In the jet core region and the impingement region, the mixing is dominated mainly by the large-scale coherent structure, while in the mixing layer and wall jet region, both the large-scale structure and small scale turbulence control the mixing.

If exposed to bulk water flow, fish lateral line afferents respond only to flow fluctuations (AC) and not to the steady (DC) component of the flow. Consequently, a single lateral line afferent can encode neither bulk flow direction nor velocity. It is possible, however, for a fish to obtain bulk flow information using multiple afferents that respond only to flow fluctuations. We show by means of particle image velocimetry that, if a flow contains fluctuations, these fluctuations propagate with the flow.Across-correlation of water motion measured at an upstream point with that at a downstream point can then provide information about flow velocity and flow direction. In this study, we recorded from pairs of primary lateral line afferents while a fish was exposed to either bulk water flow, or to the water motion caused by a moving object.Weconfirm that lateral line afferents responded to the flow fluctuations and not to theDCcomponent of the flow, and that responses of many fiber pairs were highly correlated, if they were time-shifted to correct for gross flow velocity and gross flow direction. To prove that a cross-correlation mechanism can be used to retrieve the information about gross flow velocity and direction, we measured the flow-induced bending motions of two flexible micropillars separated in a downstream direction. A cross-correlation of the bending motions of these micropillars did indeed produce an accurate estimate of the velocity vector along the direction of the micropillars.

首先我们先了解一下湿热灭菌的原理： 压力蒸汽杀菌的原理主要是使蛋白质等生物分子变性。当高温高压的蒸汽与被灭 菌物品充分接触时释放出潜热，将被灭菌物品加热，加热使蛋白质分子运动加速，互 相撞击，可致连接肽链的副键断裂，使其分子由有规律的紧密结构变为无秩序的、散 温结构，大量的疏水基暴露于分子表面, 并互相结合成为较大的聚合体而凝固、沉淀。 蒸汽灭菌是通过不可逆的破坏酶和结构蛋白，从而杀灭微生物使物品达到灭菌。 1.按照灭菌原理分类：

DMA-动态力学分析仪是对粘弹性材料表征的全能工具，可以对高分子材料的玻璃化温度，微观结构，宏观力学，蠕变和应力松弛进行测试。这篇文章可以很快地帮助您对DMA技术有初步的了解，以便进一步地对高分子材料进行深入研究。

Three-dimensional gradients of the hydroxyl radical (OH) concentration were measured in a premixed, lean natural gas / air flame by simultaneous laser induced fluorescence imaging (LIF) in a crossed-light-sheet confguration and one-dimensionally resolved Raman scattering. The technique is applied to measurements in a turbulent bluff-body flame with the aim to investigate correlations between species concentration gradients and local concentrations.

动态光散射法常被认为无法检测到大范围的粒径分布，然而事实并非如此。峰值的高度大小代表了粒子的数目多少，因而动态光散射不仅能够给出粒径的正态分布，还可以给出关于峰值的更多意义。