湍动槽

利用LaVisin公司提供的高速CMOS相机和高速图像增强器HS-IRO构成一套时间分辨PIV和PLIF联合测试系统，用于分析双稳态湍动旋流火焰中进动涡核（PVC）形成和火焰形状变化之间瞬态耦合过程。

摘要: 借助质构分析仪, 采用单项和正交的方法, 研究了4 种面团改良剂对焙烤用冷冻面团抗拉伸特性的影响, 结果表明: 单甘酯( DMG) 0.3 %、硬脂酰乳酸钠( SSL) 0.3 %、硬脂酰乳酸钙( CSL) 0.3 %、瓜尔豆胶0.8 % 单项添加时, 以及按照DMG:SSL:CSL:瓜尔豆胶=4:3:2:12 比例复合添加, 冷冻面团的抗拉伸性良好。并以此配合进行了冷冻面团制品的焙烤对照试验, 添加改良剂的制品的比体积、表皮颜色、形状、瓤芯质地结构、色泽、平滑度、芯弹柔性和口感都好于对照制品。

核磁共振技术NMR（nuclear magnetic resonance）是应用于食品领域的一项新技术，从微观上研究食品内部水分的分布和迁移情况。T2 反演谱可间接反映体系中水分结合状态、相对含量和迁移。下面是核磁共振技术在研究酶制剂对冻融下非发酵面团水分分布的影响的实验案例。

野生特级冬虫夏草干，运用国际先进的超低温真空冷冻干燥技术，升华干燥精制而成，完整地保留了冬虫夏草的虫草酸（甘露醇）、腺苷、氨基酸及微量元素，充分保留了虫草的活性和有效营养成分。采用该技术能使虫草的有效成分保有率在98%以上，而普通晒干的虫草成分比冻干的虫草成分低很多,因为晒干虫草有许多成分见到阳光就会挥发掉。

用PIV方法实验研究了5.5米宽，13.5米长水槽内浅表湍流，剪切流动中大尺度漩涡结构的产生和消失机理。

水果的种类繁多，不同的种类的水果，其组织结构、含水量及营养成分存在较大差异。因此，这也决定了各种水果进行真空冷冻干燥时，真空冷冻干燥工艺也有着显著区别。小编这次为大家简单地介绍冻干草莓的工艺。

使用电子式拉伸仪测试面团拉伸特性是一种常见的实验，通常用于研究面团的流变学性质和面包、面点等面制品的品质。以下是一般的实验操作步骤：1. 准备工作：将电子式拉伸仪放置在实验室台面上，并确保连接好所有必要的电源和传感器线缆。启动电子式拉伸仪并进行自检，确保仪器状态正常。

电子式拉伸仪是一种用于测定面粉面团拉伸特性的仪器，主要用于评估面粉的面筋质量。以下是使用电子式拉伸仪检测面粉面团拉伸特性的基本实验操作步骤：实验准备:样品准备： 获取所需的面粉样品，确保样品代表整个批次的面粉。仪器准备： 确保电子式拉伸仪处于正常工作状态，并按照制造商的说明进行预热和校准。操作步骤:样品制备：根据实验的要求，制备面粉和水的混合物，形成面团。确保按照标准的配方和配比制备面团。面团休面：让制备好的面团在室温下休面，以使其膨胀和发酵，通常休面时间根据实验的需要而有所不同。样品装置：将休好面团放入电子式拉伸仪的测试夹具中，确保夹具夹持面团的一定长度。仪器设置：打开电子式拉伸仪，按照仪器的操作手册设置所需的参数，例如拉伸速度、拉伸距离等。测试运行：启动电子式拉伸仪进行测试。仪器将逐渐拉伸面团，并记录拉伸的力和距离的关系。通常，这种测试可以测定面团的延展性、强度等拉伸特性。数据记录：一旦测试完成，记录测得的拉伸特性数据，包括最大拉伸力、拉伸距离等。

草莓又叫红莓、洋莓、地莓等，是一种红色的水果，有“水果皇后”之称。我国草莓非常丰富，产量也不断增加，但草莓制品的加工较为落后，而且草莓的采收期短，上市集中，储藏和运输时间短，如果将鲜草莓加工成干草莓、草莓粉、草莓切片、草莓速溶饮料等一系列新产品不仅解决了草莓的储存和运输问题，同时也会拓宽草莓制品市场，食用也更加方便。应用草莓中维生素、氨基酸等保健成分生产保健产品的前景非常广阔，但草莓的生理活性成分在加工中易受到破坏和损失，从而影响到其应用价值。真空冷冻干燥技术作为世界上公认最先进的食品加工技术，应用于该类产品能较好地保持食品原来的形状和色泽，减少食品香味及营养成分的损失，并具有多孔结构，速溶性和快速复水性，食用简单方便。因此，将真空冷冻干燥技术应用于草莓制品加工中。这不仅会为草莓的深加工研究如草莓中维生素、氨基酸等保健品提供生产可行性依据，同时也会对开发第三代功能食品调味料或添加剂提供指导性数据，从而为草莓资源的利用开辟较为广阔的前景。

近年来人工栽培的北冬虫夏草产量增大了，贮存和运输却成了问题。如果不及时加工，会很快腐烂变质。为了能保持其药效和营养成分，便于长期贮存和运输，真空冷冻干燥技术就成了加工冬虫夏草的重要手段。

焙烤面团产品的硬度受到许多因素的强烈影响，温度是主要考虑因素，特别是对于冷冻或冷藏的产品。不同的以面团为基础的烘焙食品除了面团成分外还含有多种其他成分，以达到最终烘焙产品所需的口感。面包、饼干、饼干、蛋糕、饺子、面饼等基本上包括面粉和水，但也可能包括酵母(或另一种膨松剂)，可能还包括其他液体、脂肪或添加剂，以改善口感、保质期、颜色和口感。为了进行质量控制，加工人员需要知道面团产品的差异，而感法可以在一定程度上评估差异，我们的客户希望采用更客观和可量化的测量方法。使用与感官相关的质构分析，可以让制造商将客观值放入他们的历史数据中，让他们更全面地了解这些影响因素对产品硬度的影响。

人天门冬氨酸转氨酶/谷草转氨酶(GOT/GPT)检测试剂盒人天门冬氨酸转氨酶/谷草转氨酶(GOT/GPT)检测试剂盒使用说明书本试剂盒仅供研究使用。检测范围： 规格：96T/48T使用目的：本试剂盒用于测定人血清,血浆及相关液体样本中人天门冬氨酸转氨酶/谷草转氨酶(GOT/GPT)含量。实 验 原 理 本试剂盒应用双抗体夹心酶标免疫分析法测定标本中人天门冬氨酸转氨酶/谷草转氨酶(GOT/GPT)水平。用纯化的抗体包被微孔板，制成固相抗体，往包被单抗的微孔中依次加入人天门冬氨酸转氨酶/谷草转氨酶(GOT/GPT)抗原、生物素化的人天门冬氨酸转氨酶/谷草转氨酶(GOT/GPT)抗体、HRP标记的亲和素，经过彻底洗涤后用底物TMB显色。TMB在过氧化物酶的催化下转化成蓝色，并在酸的作用下转化成最终的黄色。颜色的深浅和样品中的人天门冬氨酸转氨酶/谷草转氨酶(GOT/GPT)呈正相关。 使用酶标仪在450nm波长下测定吸光度（OD值），计算样品浓度

A new method to describe small scale statistical information from passive scalar fields has beenproposed by Wang and Peters (2006). They used direct numerical simulations (DNS) of homogeneous shearflow to introduce the innovative concept. This novel method determines the local minimum and maximumpoints of a fluctuating scalar field via gradient trajectories starting from every grid point in the direction ofthe steepest ascending and descending scalar gradients. Relying on gradient trajectories, a dissipation elementis defined as the region of all the grid points the trajectories of which share the same pair of maximumand minimum points. The procedure has also been successfully applied to various DNS fields of homogeneousshear turbulence using the three velocity components and the kinetic energy as scalar fields. To validatestatistical properties of these elements derived from DNS (Wang and Peters 2006, 2008), dissipation elementsare for the first time determined based on experimental data of a fully developed turbulent channelflow. The dissipation elements are deduced from the gradients of the instantaneous fluctuation of the threevelocity components u5, v5, and w5 and the instantaneous kinetic energy k5, respectively. The required 3D velocitydata is obtained investigating a 17.82 × 17.82 × 2.7 mm3 (0.356 × 0.356 × 0.054 ) test volumeusing tomographic particle-image velocimetry (Tomo-PIV). The measurements are conducted at a Reynoldsnumber of 1.7× 104 based on the channel half-height and the bulk velocity U. Detection and analysis ofdissipation elements from the experimental velocity data are presented. The statistical results are comparedto the DNS data from Wang and Peters (2006, 2008).

A new method to describe small scale statistical information from passive scalar fields has beenproposed by Wang and Peters (2006). They used direct numerical simulations (DNS) of homogeneous shearflow to introduce the innovative concept. This novel method determines the local minimum and maximumpoints of a fluctuating scalar field via gradient trajectories starting from every grid point in the direction ofthe steepest ascending and descending scalar gradients. Relying on gradient trajectories, a dissipation elementis defined as the region of all the grid points the trajectories of which share the same pair of maximumand minimum points. The procedure has also been successfully applied to various DNS fields of homogeneousshear turbulence using the three velocity components and the kinetic energy as scalar fields. To validatestatistical properties of these elements derived from DNS (Wang and Peters 2006, 2008), dissipation elementsare for the first time determined based on experimental data of a fully developed turbulent channelflow. The dissipation elements are deduced from the gradients of the instantaneous fluctuation of the threevelocity components u5, v5, and w5 and the instantaneous kinetic energy k5, respectively. The required 3D velocitydata is obtained investigating a 17.82 × 17.82 × 2.7 mm3 (0.356 × 0.356 × 0.054 ) test volumeusing tomographic particle-image velocimetry (Tomo-PIV). The measurements are conducted at a Reynoldsnumber of 1.7× 104 based on the channel half-height and the bulk velocity U. Detection and analysis ofdissipation elements from the experimental velocity data are presented. The statistical results are comparedto the DNS data from Wang and Peters (2006, 2008).

摘要：近年来，随着农业产业化的发展，对农药的需求量显著增加，除草剂是发展最为快速的一种农用化学品，其中杀草丹是一种常用的杀草剂，于此同时其在农作物中的残留及对人类健康和环境造成的毒害越来越为人们所关注。这种除草剂在环境和作物中的持效期长，由于淋溶和流失导致在使用除草剂的区域地表水中常常可检测到残留，如果水中含有残留农药，对人动植物有一定的毒害作用，并易对其他作物发生药害。因此需要对其在水体中的含量进行监控。在许多情况下，为了节省时间，资源和确保水样的可靠性而选择在现场进行检测而不是将样品带回实验室分析。设计紧凑、基于环形离子阱（CIT）质量分析器的 Griffin 460可移动 GC/MS/MS 系统可以很好的满足这样的分析要求。并可采用Twister技术，简单的萃取方式，并使用先进的PSI-Probe固体进样方式进行GC-MS检测。Twister 技术是一种实用的萃取技术，使用萃取棒萃取液体样品中的目标物质。步骤简单，只需将萃取棒放入盛有液体样品的样品瓶内，然后将样品瓶放在磁力搅拌器上进行磁力搅拌一定时间。然后将萃取棒取出，清洗，干燥之后放入PSI-Probe 就可进行GC/MS分析。

TA1质构仪在面粉、面条、米饭、乳制品、烘培食品、薯片和糖果等休闲食品、水产畜牧及其加工品、蔬菜、水果、果冻、果酱、调味酱等凝胶产品、包装材料等食品领域得到了广泛的应用，在面粉、面团方面，可根据不同的探头装置来测定其粘弹性、蠕变、松弛、拉伸强度、延展性、附着力等指标。

面团在外力作用下发生变形，外力消除后，面团会部分恢复原来状态，表现出塑性和弹性。不同品质的面粉形成的面团变形的程度以及抗变形阻力差异较大，这种物理特性称为面团的拉伸特性，也称延展特性，是面团形成后的流变学特性。

本实验使用Nexera LC-40高效液相色谱仪，采用Nexera LC-40独有的Flow Pilot功能智能自动启动，建立了快速测定复方鱼腥草合剂中黄芩苷含量的方法，且黄芩苷对照品连续测定6次，得到了良好的仪器精密度数据。

植物药种类多也导致处理难度大，大部分样品无法常规粉粹处理，中药所使用瑞绅葆分析技术（上海）有限公司的液氮冷冻研磨机部分难处理的中草药直接研磨成粉末，方便后续分析使用。

研究不同添加量的低温花生粕粉对小麦面团特性的影响，用质构仪测定面团的质构特性，并利用电镜观察面团的内部结构。

面粉、面团物性ST-Z16质构仪解决方案1.面团发酵、硬度测试装置用于面及面制品，可测量面团的流变性，面团的硬度和发酵率。样品放入测试室中.用通孔活塞的长钉把面团中随机分布的气泡驱除.再用平头活塞压制出光滑的表面，后用6mm的柱型探头测试硬度。

将导管夹片安装于夹持系统的夹槽内。调整两个滑动夹块的间距至规定的夹块间距然后紧固夹片，确保导管夹片保持有良好的贴合。将试验导管的一端自下而.上地从两个导管夹片中穿过，试验仪的上夹具夹持导管的头端。将导管的其余部分插入到装满水的圆通内，使其自然悬垂浸泡至制造商推荐的时间。调整两个滑动夹块在滑槽内的位置，使导管位于正中央。启动试验仪使导管穿过硅胶片足够的距离,记录力相对于位移的曲线。取曲线上导管管身浸湿段的平均力值报告结果。

短时间内观测污染过程，准确发现污染高度，及时获取“污染团”移动速度与方向；可作为常规战、超级站的补充，获取连续路径的空间参数。可辅助地面站点，对站点附近进行持续监测，为各监测站点制定污染改善措施提供数据支撑；能应急监测污染事故发生现场，保障公共安全，评估污染扩散趋势及通道；可为重大赛事的空气质量提供安全保障。

作为上述特性的定量评估示例，本文中介绍相当于细胞团（培养组织模型）硬度的变形强度＊1检测案例。岛津制作所的微压缩试验机MCT™ 适用于微型样品的压缩试验，可应用于柔软试样－－细胞团的测量。一般来说，细胞和组织比较脆弱，很难使用试验机进行力学定量评估，但通过MCT的高精度位移检测和试验力测量，可以完成变形强度的定量评估。使用高精度试验机进行定量评估，有望对再生医疗的普及贡献一份力量

A burner for investigating lean stratified premixed flames propagating in intenseisotropic turbulence has been developed. Lean pre-mixtures of methane at differentequivalence ratios are divided between two concentric co-flows to obtain annularstratification. Turbulence generators are used to control the level of turbulence intensityin the oncoming flow. A third annular weakly swirling air flow provides the flamestabilization mechanism. A fundamental characteristic is that flame stabilization doesnot rely on flow recirculation. The flames are maintained at a position where the localmass flux balances the burning rate, the result is a freely propagating turbulent flamefront. The absence of physical surfaces in the vicinity of the flame provides free accessfor laser diagnostics.Stereoscopic Planar Image Velocimetry (SPIV) has been applied to obtain the threecomponents of the instantaneous velocity vectors on a vertical plane above the burneroutlet where the flames propagate. The instantaneous temperature fields have beendetermined through Laser Induced Rayleigh (LIRay) scattering. Planar Laser InducedFluorescence (PLIF) on acetone has been used to calculate the average equivalence ratiodistributions. Instantaneous turbulent burning velocities have been extracted from SPIVresults, while flame curvature and flame thermal thickness values have been calculatedusing the instantaneous temperature fields. The probability distributions of thesequantities have been compared considering the separate influence of equivalence ratiostratification and turbulence.

Abstract We have experimentally detected a new effect,turbulent thermal diffusion, as predicted theoretically byElperin et al. (Phys Rev Lett (1996) 76:224–228) andassociated with the turbulent transport of inertial particles.The essence of this effect is an appearance of a non-diffusivemean flux of particles in the direction of the meanheat flux. This results in formation of large-scale inhomogeneitiesin the spatial distribution of inertial particlesthat are accumulated in regions of minimum mean temperaturein the surrounding fluid. The experiments wereperformed in oscillating grids turbulence with an imposedmean temperature gradient. We used Particle ImageVelocimetry to determine the turbulent velocity field, andan Image Processing Technique based on the analysis ofthe intensity of the Mie scattering to determine the spatialdistribution of tracer particles. Analysis of the intensity oflaser light Mie scattering by tracer particles showed thatthe tracer particles accumulate in the vicinity of the minimumof the mean temperature. The latter finding confirmsthe existence of the effect of turbulent thermaldiffusion.

With stereoscopic particle image velocimetry (SPIV) we can measure all 3 components (3C)of the velocity in the plane of a laser light sheet. SPIV makes use of 2 cameras that view thelaser light sheet from two different directions. In each measurement point in the plane of thelight sheet, each camera measures the projection of the particle displacement perpendicular toits viewing direction, and the complete velocity vector can be reconstructed from these projections.First the 2C-vector fields from each camea must be mapped (dewarped) from the imageplanes onto the measurement plane of the light sheet and interpolated on a common grid. Thenthe displacement vectors from both cameras are combined to calculate (reconstruct) the 3 componentsof the particle displacement. The dewarping and reconstruction can in principle bebased on the exact knowledge of the geometry of the setup, but most often they are based on acalibration procedure. The geometry of the setup is then derived from a set of calibration imagesfrom a grid placed in the measurement plane. A more extensive discussion of the dewarping,the reconstruction and the 3D-calibration procedure is given in (S1-S6).

The unsteady pressure field is obtained from time-resolved tomographic particle imagevelocimetry (Tomo-PIV) measurement within a fully developed turbulent boundary layer at free streamvelocity of U∞ = 9.3 m/s and Reθ = 2400. The pressure field is evaluated from the velocity fieldsmeasured by Tomo-PIV at 10 kHz invoking the momentum equation for unsteady incompressible flows.The spatial integration of the pressure gradient is conducted by solving the Poisson pressure equation withfixed boundary conditions at the outer edge of the boundary layer. The PIV-based evaluation of thepressure field is validated against simultaneous surface pressure measurement using calibrated condensermicrophones mounted behind a pinhole orifice. The comparison shows agreement between the twopressure signals obtained from the Tomo-PIV and the microphones with a cross-correlation coefficient of 0.6while their power spectral densities (PSD) overlap up to 3 kHz. The use of the Tomo-PIV system with theapplication of three-dimensional momentum equation shows higher accuracy compared to the planar versionof the technique. The combination of a correlation-sliding-average technique, the Lagrangian approach tothe evaluation of the material derivative and the planar integration of the Poisson pressure equation results inthe best agreement with the pressure measurement of the surface microphones.

岛津公司Minibeam VI型团簇离子枪最高可产出团簇大小为3000的原子团簇，加速电压最高可达20keV。团簇离子源是新型的离子源，传统的单氩离子源在刻蚀材料时会损伤材料，对于有机材料尤为明显。而团簇离子源不会造成这种损伤，温和地将材料表层进行去除，而不会改变内层材料化学态。

将试样导管夹片安装于试验机夹持系统的夹槽内。调整两个滑动夹块的间距至规定的夹块间距，然后紧固夹片，确保导管夹片保持有良好的贴合。