其他检测

Thermo Scientific TurboFlow technology is an automated online sample preparation technique for complex matrices for the mass spectrometer. It enables users to inject complex matrices such as food, plasma, urine and other biological matrices directly into the mass spectrometer – without prior sample pretreatment.

砷、硒和锑等元素在酸性条件下与强还原剂KBH4或NaBH4反应，生成气态的氢化物，由氩气带入原子化马弗炉进行原子化，测量其吸光度。

凝胶渗析色谱作为一种样品的净化手段，在国外已经普遍使用，最近几年 在国内也得到了普遍关注，尤其是在食品处理、生化分离、农业和环境样品如土 壤、污泥以及有害废水等方面。随着分析技术的发展，GPC 在我国农药残留前 处理分离、净化方面的应用越来越普遍，尤其是在富含脂肪色素等大分子的样品 分离净化方面，具有明显的净化效果。本实验依据美国国家环保局的标准方法[1] 采用凝胶色谱分离系统，成功的分离出了甲氧基DDT，其分离度大大超过EPA 方法要求。 —————————————— [1] 美国国家环保局，METHOD 3640A

传统样品前处理工作流程由萃取、净化和浓缩组成，均采取手工样品转移。针对每批样品的处理，索氏萃取、凝胶渗透色谱和氮吹等技术的样品前处理工作流程总时间超过 60 小时。 1995 年 Dionex ASE 200 的上市明显缩短了萃取时间。最 近，我们推出了配在线净化和 Thermo ScientificTM RocketTM 蒸发器的 Dionex ASE 系统，以满足整个样品前处理工作 流程的要求并将每批样品的总处理时间缩短至 6 小时。 Dionex ASE 系统与在线净化和 Rocket 蒸发器相结合的方法为分析实验室提供了全面的样品前处理解决方案。这两种技术的结合省去了人工净化步骤和人工样品传输，使样品前处理结果的准确度和重现性更高。

农药残留分析食品安全的重要组成部分。欧盟的法规，规定水稻中的最大残留限量（MRLs）有 450 以上的农药残留。多农残检测就显得十分重要。将多种农药的分析组合在一个单一的分析方法中。多残留的分析方法越来越普遍应用。随着样品前处理技术的发展，如 QuEChERS 以及选择性分离和质谱技术如 GC-MS/MS 技术的结合。气相色谱的三重四极杆质谱技术最近的发展已不仅集中在硬件上，用于驱动设备和软件处理复杂数据的能力绝对关键。这项工作涉及的高灵敏度的需要，选择性和高通量，针对大型的多残留方法使用一个新的 GC-MS/MS 系统，更快的碰撞池技术，独特的智能软件工具的使用。

方法包是赛默飞世尔科技色谱质谱部应用部门针对客户需求提出的简易仪器使用流程，方法包内所涉及的化合物均为常见的能在 GC/MS 上检测的化合物，如农药残留、多环芳烃、多氯联苯、多溴联苯和多溴联醚、邻苯二甲酸酯等。方法包的作用就是能使客户更快更简便得使用仪器，尽快上手。 方法包包括进样方法，数据处理方法（TraceFinder 方法文件夹），相关应用文章，相关标准，色谱柱信息，前处理方法，数据文件等，客户可以直接调用进样方法和数据处理方法完成化合物的定性定量分析。

The measurement of lipids in a biological matrix to study their responses to diseases, drugs, genetic modifications, and other stimuli requires a Q - TOF system with outstanding resolution, mass accuracy, and sensitivity. In this application, the 6545 Q - TOF and 1290 Infinity LC system are used to analyze an induced sputum lipid extract from a donor with chronic obstructive pulmonary disease (COPD). T he 6545 Q - TOF is tuned by novel Swarm Autotune for optimal performance in the m/z range of the lipids, and data acquired in both positive and negative ionization modes with reference mass correction

基于密度调整的放大策略可在不同的系统/色谱柱配置之间高效地进行方 法转移。实现SFC分析级应用的快速方法开发，随后可转移至制备型SFC，同时维持色谱完整性。集中梯度的使用有利于目标分析物的纯化。

石墨烯在工业上的应用，进一步带动了对石墨研磨细度的需求，本文详细介绍了FRITSCH所生产的微型球磨机P0和微型行星式球磨机P7加强型在石墨研磨中的具体应用。

高纯氧化钆在现代制造业得到重要的应用，它是特殊发光材料和磁泡记忆存储器的主要原料；氧化钆与镧一起使用，有助于提高玻璃的热稳定性；钆及其合金可作为固态磁致冷介质促进了磁制冷技术的发展。国标GBT18115.7-2006中稀土金属及其氧化物中稀土杂质化学分析方法中，其方法一为ICP 发射光谱法，但Yb 和Lu 的测定下限为0.0010%；方法二中为ICP 质谱法，但Yb 和Lu 都受Gd 各同位素的氧化物离子严重干扰，国标采用了C272 微型分离Gd 基体后测定。本方法使用ICP 光谱水平观测方式，通过对基体效应，谱线选择以及采用基体匹配，可以满足氧化钆中ug/g 级Yb 和Lu 的测定。其它稀土杂质使用iCAP Q ICPMS KED 模式测定，得到理想的结果。

快速溶剂萃取方法原理- 简单来说就是在较高的温度(50～200℃)和压力(7.0～20MPa)下用有机溶剂萃取固体或半固体的自动化方法。提高的温度能极大地减弱由范德华力、氢键、目标物分子和样品基质活性位置的偶极吸引所引起的相互作用力。液体的溶解能力远大于气体的溶解能力，因此增加萃取池中的压力使溶剂温度高于其常压下的沸点，加快提取速率。

采样瓶是环境类实验室最常用的器皿之一，有体积大，污染物杂等特点，而且瓶口较小，很难清洗。 推荐使用语瓶Q720洗瓶机，进样瓶20位清洗篮架，标准程序下进行清洗烘干

石油石化产品生产过程中，由于其特殊的物理、化学性质，复杂的衍生品的组成，使得石油石化生产及质检过程中器具的清洗变得复杂困难。通常清洗人员采用浸泡液浸泡、毛刷刷洗、超声波清洗、洗衣粉、去污粉等众多的清洗方式进行清洗工作。根据清洗经验手动摸索的清洗方式有一定的清洗效果，但其效率低下、成本高、同时有可能对清洗人员有很大危害不容忽视。随着科技发展我们更迫切需要一种全新的更安全，更简洁，更有效的清洗工艺技术，为石油石化的生产工作提供有力保障。

提及ELSD在制备分离领域的应用，天然产物无疑是使用最为广泛的一个领域。由于ELSD的通用性，事实上在常规有机合成方面也是其合适的应用领域，本文以两种常规有机合成小分子为例，介绍了ELSD在这方面的应用，突出了其相对于传统的紫外检测器的优势。

A new method to describe statistical information from passive scalar fields has been proposed by Wang and Peters “The length-scale distribution function of the distance between extremal points in passive scalar turbulence,” J. Fluid Mech. 554, 457 2006. They used direct numerical simulations DNS of homogeneous shear flow to introduce the innovative concept. This novel method determines the local minimum and maximum points of the fluctuating scalar field via gradient trajectories, starting from every grid point in the direction of the steepest ascending and descending scalar gradients. Relying on gradient trajectories, a dissipation element is defined as the region of all the grid points, the trajectories of which share the same pair of maximum and minimum points. The procedure has also been successfully applied to various DNS fields of homogeneous shear turbulence using the three velocity components and the kinetic energy as scalar fields L. Wang and N. Peters, “Length-scale distribution functions and conditional means for various fields in turbulence,” J. Fluid Mech. 608, 113 2008.

Introduction Particle image velocimetry (PIV) has proven its strength as a flow diagnostic tool to characterise instantaneous velocity fields and derived quantities such as vorticity. Recent efforts apply momentum conservation principles on planar velocity data in order to extract more quantities, such as pressure fields and integral aerodynamic forces. The theoretical concepts for this 憄lanar pressure imaging? (PPI) have been established and its practical implementation for steady (or time-averaged) flows under approximately 2D flow conditions has been demonstrated (e.g. Baur and K鰊geter 1999, Gurka et al. 1999, Oudheusden et al. 2007). The next challenge is to extend PPI to unsteady flows. This extension can be done on basis of time-resolved flow diagnostics such as time-resolved PIV (TR-PIV), cf. Kurtulus et al. 2007. Instantaneous pressure fields are particularly interesting in bluff-body flows and in fluid-structure interactions, both are important in e.g. wind-engineering applications. A serious complication in extending the planar approach is that flows tend to develop 3D instantaneous structures even for nominally 2D configurations, especially at larger Reynolds numbers.

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.

The Tomographic-PIV measurement system performances are experimentally assessed within the present study. The technique is applied to the turbulent air flow past circular cylinders in two configurations, namely the thin light sheet and the thick light sheet. In the first case the Tomo-PIV measurements are compared with stereoscopic PIV, which is assumed as a reference result. Image signal conditioning by pre-processing seems to be essential in order to achieve an accurate particle field reconstruction in presence of background light and electronic noise. The comparison shows that the two techniques are basically equivalent in the thin light sheet configuration. The 3D measurements are performed with the thick light sheet technique where the instantaneous velocity vector distribution is measured over a domain of 31x26x10 mm3 yielding 28x24x5 velocity vectors. The vortex wake past a circular section cylinder is visualized within the volume snapshots and the time-averaged flow representation shows a consistent flow pattern with respect to the geometric boundary conditions with the separated shear layers aligned along the cylinder axis.

To understand and optimize the combustion processes in new types of internal combustion engines, like gasoline direct-injection engines, non-intrusive laser-based diagnostics methods have proven to be versatile and important tools to measure combustion characteristics. Most engine developers already rely on optical methods in the development of new engines. To guarantee accurate and reliable results of optical measurements it is necessary to carefully evaluate and characterize these techniques under realistic conditions. In this work a variety of laser-based diagnostics techniques, mostly based on the tracer- LIF principle, have been evaluated for their applicability and limitations and have been applied to different spray systems – reaching from single droplets, over model sprays to fuel sprays in a firing test engine. The tracer-laser-induced-fluorescence (LIF) method is based on doping the fuel with a fluorescent substance whose fluorescence characteristics are used to measure various physical properties of the spray, such as temperature, droplet size, or droplet velocity. From these properties information about heat and mass-transfer mechanisms in the spray can be gained. However, the characteristics of the used tracers must be known in detail in order to guarantee useful and comparable results. Therefore, in this work various tracers were characterized in terms of their evaporation and temperaturedependent properties. The tracers Atto 680, Rhodamine 800 and Rhodamine B have further been tested for their applicability to realistic fuels.

Dripping convective instabilities develop under a cold thermal boundary layer when the local Rayleigh number exceeds a critical value Rac (Howard, 1966). Their 86 Interaction of two scales of thermal convection in viscous fluids interaction with a shear flow is studied experimentally in a cavity heated from one vertical wall and cooled from above. Rayleigh numbers range between 104 and 108, and Prandtl numbers are greater than 1000. Within this parameter range, a hot horizontal jet develops under the cold boundary. The instabilities dripping from the latter are therefore sheared by the flow and remain trapped in the jet, following a helicoidal path with axis parallel to the jet flow. For high jet velocities compared to the dripping velocity, 2D steady rolls prevail, while for low jet velocities, a 3D structure is observed. A phase diagram and scaling laws for the flow characteristics are determined.

The flow generated by heat convection in a long, vertical channel is studied by means of particle imagery velocimetry techniques, with the help of the thermal measurements from a previous paper (Gibert et al 2009 Phys. Fluids 21 035109). We analyse the mean velocity profiles and the Reynolds stresses, and compare the present results with the previous ones obtained in a larger cell and at a larger Reynolds number.We calculate the horizontal temperature profile and the related horizontal heat flux. The pertinence of effective turbulent diffusivity and viscosity is confirmed by the low value of the associated mixing length. We study the one-point and two-point statistics of both velocity components. We show how the concept of turbulent viscosity explains the relations between the local probability density functions (pdf) of fluctuations for temperature, vertical and horizontal velocity components. Despite the low Reynolds number values explored, some conclusions can be drawn about the small scale velocity differences and the related energy cascade. 4 Author

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

We present in this paper a novel combined scheme dedicated to the measurement of velocity in fluid experimental flows through image sequences. The proposed technique satisfies the Navier–Stokes equations and combines 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 approaches towards dense information. This results in a physics-based 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 variational and correlation methods. 1 Introduction

使用ibidi µ-Slides/µ-Dishes/µ-Plates、ibidi Pump System或ibidi Stage Top Incubators，可以将您的研究提升到一个新的水平，并获得更准确可靠的结果。从样品制备到3D细胞培养、成像和分析

此文介绍纸张涂层截面制备方案。

仪器特点 （1）适应块状、粒状、粉状、液体等不同样品测量需要； （2）自动重复测量状态可进行重复运行； （3）压力平衡时间可根据用户自行设定，设置灵活； （4）分析运行一次的时间仅几分钟； （5）对于用户选择的循环次数和定时的清洗，样品准备/清洗状态有脉冲信号（加压/减压）； （6）自带RS485、RJ45和微型打印机，以便于把数据传到打印机（TMS型号）或PC上（PNS型号）； （7）有用户可选的大压力，可消除分析样品变形所带来的危害； （8）自动打印数据报告（TMS款），包括分析结果的统计，样品号和运行条件。

某些情况特别是在完成金属涂层或绘画及冲压润滑油残留时，使用室温测得的表面能数值会产生一些问题。因此我们提供了高温表面自由能测量方法。

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。

东西分析多重PCR+核酸质谱技术适用于非洲猪瘟病毒分型、毒力强弱分株和区分野生株与疫苗株基因缺失的市场需求。有助于农业、海关等部门从分子水平追溯引发非洲猪瘟疫情的病毒来源、监测ASFV在我国的分布以及流行趋势、掌握和阻断病毒潜在的传播途径及可能的传播方式，对于ASFV的有效防控具有重要意义。

本法采用湿法消解技术处理样品，一次处理可测定钾、钠、钙、镁、铁、锰6种元素。测定钙、镁时加氯化镧做释放剂。各元素检测限优于GB5413.21标准要求。回收率在98%～102%之间。本方法准确可靠，特别适合于批量测定。