Academic literature on the topic 'Mean fluorescence intensity'
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Journal articles on the topic "Mean fluorescence intensity"
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Loupy, Alexandre, and Christophe Legendre. "From Mean Fluorescence Intensity to C1q-Binding." Transplantation 99, no. 6 (June 2015): 1107–8. http://dx.doi.org/10.1097/tp.0000000000000700.
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Jansen, Sanne, Daniel De Bruin, Simon Strackee, Ed Van Bavel, Ton Van Leeuwen, Mark I. Van Berge Henegouwen, and Suzanne Gisbertz. "PS01.186: QUANTITATIVE PERFUSION EVALUATION AFTER GASTRIC TUBE RECONSTRUCTION USING FLUORESCENCE IMAGING." Diseases of the Esophagus 31, Supplement_1 (September 1, 2018): 102–3. http://dx.doi.org/10.1093/dote/doy089.ps01.186.
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Abstract Background Poor fundus perfusion is seen as the major factor for the development of anastomotic necrosis, leakage and strictures. Quantitative imaging of tissue perfusion during reconstructive surgery, therefore, may reduce the incidence of complications. Imaging the fluorescense of intravenously administered fluorophores is an optical, non-contact method to image blood flow in real-time. However, quantitative parameters for perfusion evaluation are stil lacking. The objective of this study is to test fluorescence imaging derived quantitative parameters for perfusion evaluation of the gastric tube during surgery and to correlate these parameters to patient outcome in terms of anastomotic leakage. Methods This study included 22 patients (October 2015 - June 2016). Indocyanine green (ICG) was injected intravenously and the fluorescense intensity of the gastric tube was imaged for 2–3 minutes. At 4 locations, quantitative analysis of the fluorescent intensity over time was performed to obtain perfusion related parameters: the maximal intensity, mean slope and influx timepoint. These parameters were tested for significant differences between the four perfusion areas of the gastric tube (from normal to decreased perfusion) with a repeated ANOVA test. Furthermore, these parameters and the distance of the end of the gastroepiploic artery to the fundus and distance of the demarcation of the fluorescent signal to the fundus were compared with patient outcome in terms of anastomotic leakage development. Results The fluorescent signal could be detected in all analyzed patients (n = 20). Maximal intensity, mean slope and influx timepoint were significantly different between the base of the gastric tube and the fundus (P < 0.0001). While the distance of the watershed and the demarcation of ICG to the fundus varied between patients, the distance of the demarcation of ICG to the fundus was significantly higher in the three patients who developed anastomotic leakage (P < 0.0001). No allergic reactions on ICG were witnessed. Conclusion Intra-operative fluorescence imaging is feasible to visualize perfusion quantitatively in gastric-tube surgery, using the parameters maximal intensity, mean slope and influx timepoint. A low slope and a large distance between the fluorescence demarcation and the fundus were seen in patients who developed anastomotic leakage and could therefore allow for early risk stratification of necrosis. Disclosure All authors have declared no conflicts of interest.
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A. Wells, Denise, and Michael R. Loken. "Flow cytometric mean fluorescence intensity: The biophysics behind the number." Leukemia Research 32, no. 6 (June 2008): 845–46. http://dx.doi.org/10.1016/j.leukres.2007.10.002.
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Maryamchik, E., X. Zheng, X. Zhang, R. Machietto, C. Finn, N. Giacobbe, M. Quant, S. Choudhari, S. Kadauke, and Y. Wang. "Low CD45 mean fluorescence intensity predicts poor Post-Thaw CD34 cell viability." Cytotherapy 22, no. 5 (May 2020): S63. http://dx.doi.org/10.1016/j.jcyt.2020.03.093.
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Zhao, J., Y. X. Fu, T. Yang, Z. Y. Shen, and C. L. Wu. "Prediction of Complement-Binding Capacity of HLA Antibodies Based on Mean Fluorescence Intensity." Transplantation Proceedings 48, no. 6 (July 2016): 2235–40. http://dx.doi.org/10.1016/j.transproceed.2016.04.018.
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Wu, Chang Ni, and Yang Chen. "Lanthanide Complex-Polyethylenimine Conjugate: A Highly Luminescent Probe for Time-Resolved Fluorescence Analysis." Applied Mechanics and Materials 108 (October 2011): 212–16. http://dx.doi.org/10.4028/www.scientific.net/amm.108.212.
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Macromolecular polymer polyethylenimine (PEI) modified by many luminescent lanthanide complexes was prepared and purified. The spectral properties and lifetime of this fluorescence probe were measured. The mean number of lanthanide complexes per PEI molecule was measured and calculated. The fluorescent intensity of a macromolecule modified with lanthanide complexes is 6-fold as high as that of a lanthanide complex molecule.
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Saipetch, K., and C. Yoshimura. "Importance of correcting for fluorescence quenching in fluorescence-based prediction of trihalomethane formation potential." Water Supply 19, no. 6 (March 4, 2019): 1677–85. http://dx.doi.org/10.2166/ws.2019.039.
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Abstract Fluorescence excitation–emission matrix (EEM) spectroscopy is often used to determine the levels of trihalomethane (THM) precursors in natural organic matter. However, humic substances are known to quench the fluorescence of amino acids and proteins. To date, none of the EEM-based models for predicting THM formation potential (THMFP) have explicitly accounted for these quenching effects. Thus, we investigated the importance of correcting for fluorescence quenching during THMFP prediction. Fluorescence titration experiments revealed that the correction improved the accuracy of THM prediction. EEM-based models using the corrected fluorescence intensity displayed the highest accuracy (R2 > 0.99; mean absolute error 8.1 μg/L and 13.9 μg/L for chloroform and bromoform, respectively) among models using individual parameters of EEM intensity, dissolved organic carbon (DOC), ultraviolet absorbance at 254 nm (UV254), specific UV254 (SUVA254) and differential ultraviolet absorbance at 272 nm (ΔUV272). Thus, EEM-based models require both the fluorescence intensity of a humic-like component and the corrected fluorescence intensity of a protein-like component for accurate THMFP prediction, for both chlorination and bromination processes. We also found it to be unnecessary to combine DOC with EEM intensity in terms of prediction accuracy, as long as the fluorescence quenching correction is applied.
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Wang, Jun Sheng, You Nan Song, Jin Yang Sun, Hui Chu, Jin Hu Jiang, Xin Xiang Pan, Ye Qing Sun, and Dong Qing Li. "A Microfluidic Cytometer for Quantitative Evaluation of Radiation Dose by γ-H2AX." Applied Mechanics and Materials 522-524 (February 2014): 1119–22. http://dx.doi.org/10.4028/www.scientific.net/amm.522-524.1119.
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Evaluation of radiation dose is very important for the detection of radiation damage. γ-H2AX is a popular biological dosimeter to evaluate the radiation effect. Typically, bulky and expensive commercial flow cytometers are used to detect γ-H2AX. This paper presents a miniaturized and highly sensitive cytometer using a microfluidic chip for evaluating the radiation dose by detecting the mean immunofluorescence intensity of γ-H2AX. A compact optical focusing system and a shift-phase differential amplifier are designed to improve the detection sensitivity. Sample lymphocyte cells are stained by FITC fluorescent dye after being irradiated by UVC. Comparison experiments between the developed miniature cytometer and a commercial flow cytometer were conducted under different radiation doses. The developed microfluidic cytometer can also demonstrate a good linear correlation between the measured fluorescence intensity and the irradiation dose with a detection limit similar to that of the commercial flow cytometer. The developed cytometer can evaluate quantitatively the radiation dose by the mean fluorescence intensity of γ-H2AX with a significantly smaller amount of blood samples than a commercial flow cytometer.
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Frénoy, J. P., F. Emmanuel, and J. M. Salmon. "Use of quantitative image microfluorometry to follow fluorescent ricin internalization in single living cells." Journal of Histochemistry & Cytochemistry 42, no. 5 (May 1994): 627–33. http://dx.doi.org/10.1177/42.5.8157934.
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We used microspectrofluorometry and videomicrofluorometry to follow the binding and internalization of fluorescein-labeled toxic lectin ricin in living Zajdela hepatoma cells. Microspectrofluorometry showed that when ricin was specifically labeled on its B-chain with one molecule of fluorescein (ABF), its fluorescence spectrum did not alter during its binding to the cell surface and subsequent internalization. This enabled us to use image analysis to follow cell internalization of labeled ricin. Accordingly, we measured the appropriate fluorescent cell parameters, comprising total fluorescence intensity, cell surface area, mean fluorescence intensity and its standard error, and used the measurements for mono- and biparametric studies of cell fluorescence distribution. The results showed that (a) ricin binds two different subpopulations of Zajdela hepatoma cells, (b) Zajdela hepatoma cells internalize ricin rapidly and after a relatively stable period of 1-2 hr, internalization starts again at 4 hr, and (c) the distribution of intracellular fluorescence is heterogeneous and ABF accumulates in certain cellular localizations. Our results demonstrate that quantitative microfluorometry is an effective and interesting approach for real-time studies of macromolecule internalization in living cells.
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Baker, A., R. Inverarity, and D. Ward. "Catchment-scale fluorescence water quality determination." Water Science and Technology 52, no. 9 (November 1, 2005): 199–207. http://dx.doi.org/10.2166/wst.2005.0319.
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Chemical water quality determinants and river water fluorescence were determined on the River Tyne, northeast England. Statistically significant relationships between nitrate (r=0.87), phosphate (r=0.80), ammonia (r=0.70), biochemical oxygen demand (BOD) (r=0.85) and dissolved oxygen (r=−0.65) and tryptophan-like fluorescence intensity were observed. The strongest correlations are between tryptophan-like intensity and nitrate and phosphate, which in the Tyne catchment derive predominantly from point and diffuse source sewage inputs. The correlation between BOD and the tryptophan-like fluorescence intensity suggests that this fluorescence centre is related to the bioavailable or labile dissolved organic matter pool. The weakest correlations are observed between tryptophan-like fluorescence intensity and ammonia concentration and dissolved oxygen. The weaker correlation with ammonia is due to good ammonia treatment within the wastewater treatment plants within the catchment, and that with dissolved oxygen due to the natural aeration of the river such that this is not a good indicator of water quality. Mean annual tryptophan-like fluorescence intensity, measured by both bench and portable spectrometers, agrees well with the General Water Quality Assessment as determined by the England and Wales environmental regulators, the Environment Agency.
Dissertations / Theses on the topic "Mean fluorescence intensity"
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Janíček, Tomáš. "Vliv hybridizačních směsí na intenzitu fluorescence při in situ hybridizaci." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2019. http://www.nusl.cz/ntk/nusl-401944.
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Fluorescenční in situ hybridizace (FISH) je široce používaná metoda pro detekci určité sekvence DNA na chromozomech. Cílem práce je porovnání tří různých chemických sloučenin (formamidu, ethylenkarbonátu a sodných kationtů) používaných ve směsích pro in situ hybridizaci. Složení těchto směsí ovlivňuje renaturaci DNA a je důležité porovnat jejich fyzikální vlastnosti. Práce je rozdělena do dvou hlavních částí. První část se zabývá otázkou termodynamických parametrů používaných pro experimenty FISH, jako je teplota tání, entalpie přechodu DNA ze dvoušroubovice na vlákno nám dává přehled o energii potřebné k tomto přechodu a interakcích mezi bázemi a každou složkou směsi. Kromě toho hodnoty entropie určují poř uvnitř směsi - systém DNA. Druhá část porovnává intenzitu fluorescenčního signálu při optimalizovaných teplotách tání sondy použité pro in situ hybridizaci. Jako sonda byla použita sub-telomerní repetice X43.1, která je umístěna na Y chromozomu rostlinného modelového organismu Silene latifolia. Směs obsahující formamid má nejlepší výkon při delším postupu hybridizace, zatímco ethylenkarbonát poskytuje vyšší intenzitu signálu, a proto je vhodnější pro rychlé FISH protokoly.
Book chapters on the topic "Mean fluorescence intensity"
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Eftink, Maurice R., and Glen D. Ramsay. "Temperature- and Pressure-Induced Unfolding of a Mutant of Staphylococcal Nuclease A." In High Pressure Effects in Molecular Biophysics and Enzymology. Oxford University Press, 1996. http://dx.doi.org/10.1093/oso/9780195097221.003.0008.
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Nuclease conA is a hybrid version of Staphylococcal nuclease that contains a six amino acid (β-turn substitute from concanavalin A. This hybrid protein has a much lower thermodynamic stability than does the wild-type protein. This enables the unfolding of the protein to be achieved easily by several types of perturbations. From temperature-, pressure-, and denaturant-induced unfolding studies, we have found the free energy change for unfolding, ΔG°un, to be approximately 1.4 kcal mo−1 at pH 7, 0.1 M NaCI, and 20 °C, as compared to a thermodynamic stability of approximately 5.5–6 kcal mo−1 for wild-type nuclease A. Due to its reduced thermodynamic stability, nuclease conA also shows evidence of unfolding at low-temperature (cold denaturation), with a temperature of maximum stability of 13–15 °C. The thermal unfolding of nuclease conA is shown to be two-state by simultaneous measurement of fluorescence and CD changes as a function of temperature, using a modified AVIV CD instrument. Increased hydrostatic pressure unfolds nuclease conA in what appears to be a two-state manner, with an apparent of ΔV°un approximately —100 ml mol−1. From studies of the pressure (p)-induced unfolding of this hybrid protein as a function of temperature (T), we can define the complete p-T free energy surface for the unfolding transition. In auxiliary studies, we have characterized the fluorescence intensity decay and anisotropy decay of the single tryptophan residue (Trp-140) of nuclease conA in the native state and in the unfolded state induced by temperature, pressure, and denaturant. For each type of perturbation, there is a red shift in fluorescence, a lowering of the mean fluorescence lifetime, and a lowering of the rotational correlation time of the tryptophan residue to a value of ~1 ns (compared to 10–15 ns for the native state). The thermodynamics of the unfolding of proteins has received renewed interest in recent years, owing to the availability of a rich variety of mutant proteins and to advances in our understanding of their structural features. Among the questions being asked are, What are the relative energetic contributions of the hydrophobic effect and other interaction forces?
Conference papers on the topic "Mean fluorescence intensity"
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Startceva, Sofia, Jerome G. Chandraseelan, Ari Visa, and Andre S. Ribeiro. "Quantitative Estimation of Long-living Fluorescent Molecules from Temporal Fluorescence Intensity Data Corrupted by Nonzero-mean Noise." In 9th International Conference on Bio-inspired Systems and Signal Processing. SCITEPRESS - Science and and Technology Publications, 2016. http://dx.doi.org/10.5220/0005605900170024.
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Suzuki, Hiroki, Kouji Nagata, Yasuhiko Sakai, and Ryota Ukai. "An Experimental Study on Turbulent Mixing of High-Schmidt-Number Scalar in Grid Turbulence by Means of PIV and PLIF." In ASME-JSME-KSME 2011 Joint Fluids Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/ajk2011-21013.
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Turbulent mixing of high-Schmidt-number passive scalar in shear-free grid turbulence is experimentally investigated using a water channel. The Reynolds number based on the mesh size of the grid and cross-sectionally averaged mean velocity is 2,500. Rhodamine B (fluorescent dye) was used as a high-Schmidt-number passive scalar. The Schmidt number is about 2,100. The time-resolved particle image velocimetry (PIV) and the planar laser induced fluorescence (PLIF) technique were used to measure instantaneous two-component velocities and nondimensional concentration. Our PLIF algorithm corrects the following errors: spatiotemporal variation of local excitation intensity due to an inhomogeneous concentration field along the light path, time variation of fluorescence quantum yield, and spatiotemporal variation of incident laser intensity. The results show that the vertical profile of mean scalar can be well approximated by the error function. In contrast, the profile of scalar variance in outer region of the mixing layer cannot be approximated by the Gaussian profile. In addition, the half width of mean scalar is larger than that of the scalar variance profile.
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Doublet, Pierre, Christine Lempereur, Virginel Bodoc, Mikael Orain, and Pierre Gajan. "Planar droplet sizing: Application to a spray of Jet A1 kerosene." In ILASS2017 - 28th European Conference on Liquid Atomization and Spray Systems. Valencia: Universitat Politècnica València, 2017. http://dx.doi.org/10.4995/ilass2017.2017.4698.
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Optical techniques are widely employed for their non-intrusive behavior and are applied to two-phase flowinvestigations. Until now, the most commonly used technique to determine the droplet size is the Phase Doppler Anemogranulometry, although it is time consuming for an overall injector characterization. An imaging technique called Planar Droplet Sizing has been used to offer an alternative and provide a spatially-resolved 2D map of the Sauter Mean Diameter (SMD). The measurement is based on the ratio between laser-induced fluorescence and scattered light intensities which are assumed to be proportional respectively to the droplet volume and droplet surface area. However, previous studies revealed that the dependence of fluorescence intensity on the droplet volume can be altered by the absorption of light in the liquid. The scattered light intensity depends on the scattering angle and intensity variations within the field of view must be avoided.The aim of this study is to make the PDS technique operational for a Jet A-1 kerosene spray. A strong absorption of liquid kerosene appears under UV excitation at 266 nm making the technique unsuitable. Under visible excitation at 532 nm, a fluorescent tracer (Pyrromethene 597) must be added to the kerosene to enhance the fluorescence signal. To prevent scattered light intensity variations within the field of view, an optimal scattering angle close to 115° is required. An image processing algorithm is proposed in order to reduce the effects ofmultiple scattering.DOI: http://dx.doi.org/10.4995/ILASS2017.2017.4698
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Griebel, P., R. Scha¨ren, P. Siewert, R. Bombach, A. Inauen, and W. Kreutner. "Flow Field and Structure of Turbulent High-Pressure Premixed Methane/Air Flames." In ASME Turbo Expo 2003, collocated with the 2003 International Joint Power Generation Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/gt2003-38398.
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The present study focuses on the flow field characterization of highly turbulent premixed flames, typical for stationary gas turbines. Mean flame front position and flame front structure at high inlet temperatures, lean mixtures, and high pressures are studied, too. Turbulence intensities and integral length scales have been measured in an isothermal flow field with the help of Particle Image Velocimetry (PIV). Mean flame front position and flame structure have been studied using Planar Laser-Induced Fluorescence (PLIF) of the OH radical. Turbulence intensities and integral length scales have been measured for different turbulence generating grid geometries and operating conditions. The results show that the combustor flow field can be divided in a region close to the combustor head, where grid-generated turbulence is dominant, and a region further downstream, strongly influenced by turbulence generated in the shear layer. In general the measured turbulence intensity scales well with the bulk velocity. For a systematic variation of the turbulent Reynolds number, Damko¨hler number, and Karlovitz number the mean flame front position and the flame front structure were investigated. Increasing the pressure and thereby mainly increasing the turbulent Reynolds number only slightly affects the mean flame front position but increasingly corrugates the flame front. Increasing the bulk velocity and thereby the turbulence intensity does not affect the mean flame front position but due to the higher turbulence the flame front is increasingly corrugated.
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Kitagawa, Atsuhide, Kazuyasu Sugiyama, Masa-aki Ashihara, Koichi Hishida, and Yoshiaki Kodama. "Measurement of Turbulence Modification by Microbubbles Causing Frictional Drag Reduction." In ASME/JSME 2003 4th Joint Fluids Summer Engineering Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/fedsm2003-45648.
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In this research, in order to clarify the mechanism for drag reduction caused by microbubbles, the turbulence structure of flow field including microbubbles in a horizontal channel is experimentally investigated using particle tracking velocimetry and laser induced fluorescence (PTV/LIF) technique. First, we discuss the particle image velocimetry (PIV) and PTV results for the liquid phase velocity detection. Second, using instantaneous measurement data, we obtain the profiles of the mean velocity, turbulence intensity and Reynolds stress of the liquid phase. In order to obtain the information of both the liquid and gas phases simultaneously, furthermore, we propose a new system based on the combination of PTV, LIF and infrared shadow technique (IST).
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Upadhyay, Jagannath, Daniel S. Park, Karsten E. Thompson, and Dimitris E. Nikitopoulos. "3D Measurements of Nano-Particle Transport in Complex 2.5D Micro-Models." In ASME 2015 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/imece2015-50635.
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A confocal Micro-Particle Image Velocimetry (C-μPIV) technique along with associated post image processing algorithms is established to quantify three dimensional distributions of nano-particle velocity and concentration at the micro-scale (pore-scale) in 2.5D porous media designed from a Boise rock sample. In addition, an in-situ, non-destructive method for measuring the geometry of the micro-model, including its depth, is described and demonstrated. The particle experiments use 900 nm fluorescence labeled polystyrene particles at a flow rate of 10 nLmin−1 and confocal laser scanning microscopy (CLSM), while in-situ geometry measurements use regular microscope along with Rhodamine dye and a depth-to-fluorescence-intensity calibration. Image post-processing techniques include elimination of background noise and signal from adsorbed nano-particle on the inner surfaces of the micro-model. In addition, a minimization of depth of focus technique demonstrates a capability of optically thin slice allowing us to measure depth wise velocity in 2.5D micro-model. The mean planar components of the particle velocity of the steady-state flow and particle concentration distributions were measured in three dimensions. Particle velocities range from 0.01 to 122 μm s−1 and concentrations from 2.18 × 103 to 1.79 × 104 particles mm−2. Depth-wise results show that mean velocity closer to the top wall is comparatively higher than bottom walls, because of higher planar porosity and smooth pathway for the nano-particles closer to the top wall. The three dimensional micro-model geometry reconstructed from the fluorescence data can be used to conduct numerical simulations of the flow in the as-tested micro-model for future comparisons to experimental results after incorporating particle transport and particle-wall interaction models.
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Timite, Brahim, Cathy Castelain, and Hassan Peerhossaini. "Pulsating Flow for Mixing Intensification in a Twisted Curved Pipe." In ASME/JSME 2007 5th Joint Fluids Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/fedsm2007-37065.
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This work concerns the manipulation of a twisted curved pipe flow for mixing enhancement. Previous work [1,2,3] has shown that geometrical perturbations to a curved pipe flow can increase mixing and heat transfer by chaotic advection. In this work the flow entering the twisted pipe undergoes a pulsatile motion. The flow was studied experimentally and numerically. The numerical study is carried out by CFD code (Fluent 6) in which a pulsated velocity field is imposed as an inlet condition. The experimental setup involves principally a “Scotch-yoke” pulsatile generator and a twisted curved pipe. Laser Doppler velocimetry (LDV) measurements have shown that the Scotch-yoke generator produces pure sinusoidal instantaneous mean velocities with a mean deviation of 3%. Visualizations by laser-induced fluorescence (LIF) and velocity measurements, coupled with the numerical results, have permitted analysis of the evolution of the swirling secondary flow structures that develop along the bends during the pulsation phase. These measurements were made for a range of steady Reynolds number (300 ≤ Rest ≤ 1200), frequency parameter (1 ≤ α = r0.(ω/υ)1/2 < 20), and two velocity components ratios (β = Umax,osc/Ust). We observe satisfactory agreement between the numerical and experimental results. For high β, the secondary flow structure is modified by a Lyne instability and a siphon effect during the deceleration phase. The intensity of the secondary flow decreases as the parameter α increases during the acceleration phase. During the deceleration phase, under the effect of reverse flow, the secondary flow intensity increases with the appearance of Lyne flow. Experimental results also show that pulsating flow through a twisted curved pipe increases mixing over the steady twisted curved pipe. This mixing enhancement increases with β.
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Hedman, Paul O., Thomas H. Fletcher, Stewart G. Graham, G. Wayne Timothy, Daniel V. Flores, and Jason K. Haslam. "Observations of Flame Behavior in a Laboratory-Scale Pre-Mixed Natural Gas/Air Gas Turbine Combustor From PLIF Measurements of OH." In ASME Turbo Expo 2002: Power for Land, Sea, and Air. ASMEDC, 2002. http://dx.doi.org/10.1115/gt2002-30052.
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The objective of this study was to obtain instantaneous planar laser induced fluorescence (PLIF) images of OH in a laboratory-scale, gas-turbine combustor (LSGTC) with a pre-mixed, swirl-stabilized, natural gas flame. Instantaneous PLIF images of OH were obtained at each of four operating conditions (high swirl and medium swirl at fuel equivalence ratios of 0.80 and 0.65). Comparison of the instantaneous images illustrates the stochastic nature of the flame structure. Pixel by pixel statistical analysis of each collection of images allowed both mean and standard deviation images to be generated, and analysis at selected locations has allowed probability density functions to be obtained in various regions of the flame structure. PLIF images of OH, along with visual photographs and video recordings, showed a wide variation in flame structure for the different operating conditions. The variations in flame shapes are primarily a result of the effect of the swirl intensity and fuel equivalence ratio. Changes in the airflow rate over an order of magnitude do not seem to affect the visual flame structure in this experiment. Operation at φ = 0.80 produced the most stable flames with both injectors. The flame with the high swirl injector was more coalesced and closer to the injector than with the medium swirl injector. At φ = 0.65, the flame was quite unstable for both swirl injectors. With the medium swirl injector, the flame would oscillate between two different flame structures, one that was more or less attached to the vortex funnel, and one that was lifted well above the vortex funnel. The MS case at φ = 0.65 was at the very edge of the lean flammability limit, and would on occasion extinguish.
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Ball, J., M. Greaves, C. Jackson, J. Peel, and F. E. Preston. "DN-9693: A PHOSPHODIESTERASE INHIBITOR WITH A PLATELET MEMBRANE EFFECT." In XIth International Congress on Thrombosis and Haemostasis. Schattauer GmbH, 1987. http://dx.doi.org/10.1055/s-0038-1643583.
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We have examined the effect of DN-9693 (piperidinyl - imidazo - quinazoline: Daiichi Seiyaku, Japan) a water soluble phosphodiesterase inhibitor on platelet aggregation, secretion and thromboxane B2 (TXB2) production. In platelet rich plasma and at concentrations of 2uM and 5uM the drug significantly inhibited aggregation induced by adenosine diphosphate, collagen and sodium arachidonate. TXB2 production and release of adenosine tri-phosphate and 14C 5-hydroxytryptamine were also significantly inhibited by the drug. Cyclic adenosine mono-phosphate accumulation was enhanced. Inhibition of ristocetin induced platelet agglutination was an unexpected finding and further experiments were undertaken to explore this. These suggested no specific effect against a plasma factor (von Willebrand factor) and reduced expression of the platelet membrane glycoprotein Ib was implicated. To investigate this further we examined the effect of DN-9693 on the binding of a monoclonal antibody (McAb) to platelet membrane glycoprotein lb (AN51). This was assessed by a FACS IV flow cytofluorimeter utilising a goat anti-mouse fluorescein isothiocyanate (FITC) labelled secondary antibody. Similar experiments were also performed with McAbs to the membrane glycoprotein complex IIb/IIIa (M148) and also to glycoprotein IIIa (C17). In platelet rich plasma, at concentrations which have been shown to inhibit aggregation, DN-9693 significantly reduced the mean fluorescence intensity of the cells coated with McAb AN51 in a dose related manner. This strongly suggested a drug effect against the glycoprotein Ib receptor site. Also, the drug appeared to enhance the binding of McAb C17 to glycoprotein IIIa. This study indicates that in addition to potent phosphodiesterase inhibitor activity, DN-9693 causes a platelet surface membrane change which is associated with reduced expression of membrane glycoprotein Ib.
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Niibori, Yuichi, Masayuki Narita, Akira Kirishima, Taiji Chida, and Hitoshi Mimura. "Fluorescence Emission Behavior of Eu(III) Sorbed on Calcium Silicate Hydrates Formed With No Dried Process." In 2013 21st International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icone21-16524.
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Calcium silicate hydrate (CSH) is a main component of cement-based material required for constructing the geological repository. As in many countries, since the repository in Japan is constructed below water table, we must consider the interaction of radionuclide with cement materials altered around the repository after the backfill. Using fluorescence emission spectra, so far, the authors have investigated the interaction of Eu(III) (as a chemical analog of Am(III)) with CSH gels formed with no dried process, considering a condition saturated with groundwater. However, in such fluorescence emission behaviors, a deexcitation process of OH vibrators of light water and a quenching effect caused by Eu-Eu energy transfer between Eu atoms incorporated in the CSH gel must be considered. This study examined the fluorescence emission behavior of Eu(III) sorbed on CSH gels formed with no dried process, by using La(III) (non-fluorescent ions) as a diluent of Eu(III). Furthermore, the CSH samples were synthesized with CaO, SiO2, and heavy water (D2O) as a solvent in order to avoid the obvious deexcitation process of OH vibrators of light water. This study prepared CSH samples with the Ca/Si ratio set to 1.6, 1.0, and 0.5. A 1 mM solution of a given combination of Eu(III) and La(III) (Eu(III) content: 100%, 67%, 50% or 33%) was added into CSH gel sample. The contact time-period of the CSH gel with the Eu(III)/La(III) solution was set to 60 days. In the results, the peak around 618 nm was split into two peaks of 613 nm and 622 nm in the cases of Ca/Si = 1.0 and 1.6. Then, the peak of 613 nm decreased with increment of Eu(III)/La(III) ratio. This means that the relative intensity of 613 nm is useful to quantify the amount of Eu(III) incorporated in CSH gel. Besides, the intensity peak of 584 nm decayed with increment of Eu/La ratio, suggesting a quenching effect due to Eu-Eu energy transfer. However, the decay behavior of the fluorescence emission did not depend on the Eu/La concentration ratio. That is, such a quenching effect is neglectable. Additionally, the low Ca/Si ratio samples underwent slow attenuation of fluorescence and showed profiles similar to those of high Ca/Si ratio samples. Therefore, low Ca/Si ratio samples also include the reaction forming a complex on the surface of CSH gel with Eu(III). In other words, even if Ca/Si ratio is lower than 1.0, CSH gels would retard the migration of radionuclides released from the repository.