Size Measurement Techniques Research Articles

Association of temporomandibular joint space and condylar head position with different skeletal patterns among the Malaysian population

During growth and development of the head and neck, some degree of interaction and interdependence between skeletal pattern with temporomandibular joint (TMJ) space and condylar head position occurs. Results from previous studies are varied; some reporting significant difference of TMJ space or condylar head position among the skeletal patterns, whilst others have shown that no such association is present. Considering that previous studies have been conducted in populations outside of Malaysia and the importance of determining the correlation between skeletal and TMJ morphology, this retrospective study was done to evaluate the TMJ space and condylar head position in different skeletal patterns among the Malaysian population using computed tomography (CT) images. A total of 90 CT images of the head and neck were included. Skeletal pattern (class I, II, III) was determined from each CT image based on the ANB angles obtained from reconstruction of these images. The TMJ space measurement and condylar head position were determined from sagittal images based on established landmarks from the reconstructed CT images. Statistical analysis was used to compare the TMJ space and condylar head position across the three skeletal classes and assess its significance. The results of this study demonstrated that there was no significant association between TMJ space or condylar head position in the different skeletal patterns among the Malaysian population. It is recommended that a prospective study with large sample size and standardized measurement techniques be implemented in the future to determine the precise association between TMJ morphology and different skeletal patterns.

Unification of particle size analysis results, part 1 − comparison of particle size distribution functions obtained by various measurement methods

This article concerns comparing the grain size distribution functions of mineral powder samples and analyzes errors obtained by various measurement methods. The research used three standard and currently most frequently used methods: sieve analysis, laser diffraction analysis and vision analysis. The most important research, from the point of view of unification of results, consisted in performing precise analyses of the grain size of mineral powders (fly ash, gneiss, quartz sand and Cu ore) in various grain classes. The measurement techniques used in the research and issues related to measurement analytics were characterized. The distribution functions of the grain size distributions of the tested material samples were obtained by different measurement methods and the measurement errors were compared. Using the coefficient of variation CV calculated for characteristic particle diameters, the accuracy of measurements made using various methods was analyzed. It has been shown that different particle size measurement techniques give significantly different particle size distributions for the same material, with the grain size distribution of the measured samples having a greater impact on the results than the material itself. The lowest values of the coefficients of variation were obtained for wet sieve analysis and the highest for laser diffraction. Reliable data informing about grain size distributions were generated for further model calculations necessary to standardize the results between measurement methods.

Flocculation Behavior of Ultrafine Silica Particles in Acid Leaching Pulp by Nonionic Polymeric Flocculants

Sedimentation of ultrafine silica particles that exist in acid leaching pulp and their separation from Pregnant Leach Solution largely determines the efficiency of a hydrometallurgical process utilizing copper oxide ore. Thickener on a larger scale can allow longer sedimentation, generating low overflow turbidity but high economic input. In this paper, the flocculation behavior of quartz particles in sulfuric acid solution using nonionic flocculants polyethylene oxide (PEO) and polyacrylamide (PAM), as well as ionic cofactor montmorillonite (MMT) and nonionic cofactor tannic acid (TA), were investigated, with the dynamic size of flocs and counts of fines being monitored using an in situ particle size measurement technique, namely the focused beam reflectance measurement (FBRM), under turbulent conditions. Attention was paid to variables affecting quartz flocculation properties from both physicochemical and hydrodynamic aspects such as shear intensity. The flocculation mechanism was investigated using zeta potential and dynamic light scattering measurements. It was found that the TA promotes the bridging flocculation of PEO-quartz by forming associative complexes with larger clusters in solution, while MMT electrostatically adsorbs on the quartz surface, enhancing its bridging with PAM. Low turbidity benefited from the higher shear resistance of the compact flocs structure provided by PEO/PEO + TA/PAM + MMT. Efficient solid–liquid separation was achieved by using the synergistic flocculation of small molecule cofactors and polymer flocculants.

Drop Size Measurement Techniques for Agricultural Sprays:A State-of-The-Art Review

Plant protection control based on the spray application of plant protection products is a very complex task depending on a series of factors, among which droplet size is the most influential for deposition and pesticide effectiveness. In fact, the adoption of the correct droplet size can ensure that the required dose reaches the target area and is not wasted, minimizes the off-target losses due to evaporation, drift and run-off and, at the same time, enhances the operator’s safety in terms of inhalation, ingestion and dermal exposure. In this paper, after defining some mean characteristic diameters helpful for a description of a drop population and focusing on the main drop size distribution functions for the statistical characterization of sprays, a critical analysis of known methods, both intrusive and non-intrusive, for drop size measurement is carried out by reviewing the literature. Among intrusive methods, the liquid immersion method and the use of water-sensitive papers are discussed, whereas, among non-intrusive methods, laser-based systems (laser diffraction, phase Doppler particle analysis) and high-speed imaging (shadowgrapy) are presented. Both types of method, intrusive and non-intrusive, can be used in machine-learning-based approaches exploiting regression techniques and neural network analysis.

Method for measuring bubble size under low-light conditions for mass transfer enhancement in industrial-scale systems

Shadowgraphy-based image processing studied in the literature on multiphase processes has led to meaningful advances in mass transfer enhancement via interfacial area enlargement. However, the industrial applications of shadowgraphy have been limited due to the requirement of an additional light source at specific locations. To overcome this limitation, in this study, a new bubble size measurement technique in low-light conditions is proposed. The technique uses reflected LED image on the bubble surface to estimate the bubble size in low-light conditions and includes a newly derived measurement correlation model, which was validated with lab-scale experimental data. Furthermore, the proposed model was applied to industrial-scale bubble systems for hydrogen fluoride (HF) removal. Using the bubble properties identified through analysis, the overall mass transfer coefficient (OMTC) was determined as an indicator of HF mass transfer enhancement. The optimal conditions for HF mass transfer were determined by identifying the system with the highest OMTC. By manipulating the pressure difference and flow rate, OMTC was increased by ∼78% of the base case.

Characterisation of particle stress in turbulent impeller flows utilising photo-optical measurements of a flocculation system – PART 1

This study aims at developing an experimental method to characterise the fluid dynamic stress acting on particles in a lab-scale stirred tank reactor. The method is based on a photo-optical inline particle size measurement technique, which is able to capture the complex morphology of a stress-sensitive clay-floc system. The novel image-based analysis uses a Convolutional Neural Network (CNN), which was trained for particle detection. Its output provides a high-quality particle recognition for subsequent size and shape analysis throughout the flocculation process under various experimental conditions. The flocculation system is used to characterise the stress induced by four impeller geometries in the reactor. The obtained changes of floc size and shape allow to evaluate the particle stress in more detail compared to previous studies. The agreement of main findings of the floc breakage process with known literature assesses the developed method to be applied successfully in further studies.

Frother Characterization Using a Novel Bubble Size Measurement Technique

Bubble size measurement is a vital part of flotation system analysis and diagnostics. This work evaluates a commercial camera probe as a novel method for in situ bubble size measurement. This device is compared to the conventional Anglo Platinum Bubble Sizer (Stone ThreeTM). It was found that, in laboratory applications, the in situ bubble size analysis technology appears to be a more user-friendly and reliable option for determining bubble size in flotation, whereas the Anglo Platinum Bubble Sizer is more applicable for full scale industrial work. This probe was then used to conduct a rigorous comparison of the behavior of different frother chemistries at a variety of background solution ionic strength conditions. The critical coalescence concentrations and the minimum Sauter mean bubble diameters were determined. Five frothers were compared in terms of their ability to reduce bubble size and sensitivity to salinity. In order to adjust plant recipe and control strategy accordingly, it is recommended that the plant would need to use less frother during periods of the high salinity of process water to achieve the minimum Sauter mean bubble size.

Measurement of multiple spleen lengths is not necessary for non-invasive prediction of high-risk esophagogastric varices.

To validate an appropriate spleen size measurement technique for the prediction of high-risk esophagogastric varices. This retrospective cross-sectional study included 369 patients who underwent ultrasonography and computed tomography (CT) of the spleen and esophagogastroduodenoscopy between January 2018 and December 2020. Maximum spleen length, width, and craniocaudal length were measured in a longitudinal view. The two-dimensional (2D) spleen index (maximum length×maximum width in the longitudinal view) was calculated. A three-dimensional (3D) spleen index was then defined as follows: 2D spleen index×maximum length in the transverse view. The similarity in spleen volume measured by CT and ultrasonography (spleen index) was assessed by the correlation coefficient. The diagnostic accuracies of the spleen index, platelet/spleen length, and platelet/spleen index were calculated to determine the overall diagnostic accuracy. Compared to the other spleen indices, our 3D spleen index was significantly better correlated with spleen volume on CT (r=0.91, 95% confidence interval 0.89-0.92, p<0.001). Receiver-operating characteristic curve analyses revealed no significant difference between the 3D and 2D indices (p=0.228) but did show a significant difference between the 3D and one-dimensional indices (p=0.020). Although the area under the curve for the platelet count combined with the spleen index or length was higher than that for our 3D index, there was no significant difference between platelet count and spleen index or length (p=0.078). Platelet/spleen length has a reasonable ability to predict high-risk esophagogastric varices, even though measurement of two or three factors can be correlated with spleen volume.

Modelling Spray Pressure Effects on Droplet Size Distribution from Agricultural Nozzles

For spray applications, drop size is the most important feature as it affects all aspects of a phytosanitary treatment: biological efficacy, environmental pollution, and operator safety. In turn, drop size distribution depends on nozzle type, liquid properties, and working pressure. In this research, three nozzles were studied under ordinary working conditions and the effect of pressure on drop size distribution was assessed. The nozzles under test, all from Albuz (France), were an orange hollow cone nozzle ATR 80 (European color code), an air induction flat spray nozzle AVI 11003, and an air induction hollow cone nozzle TVI 8002. The ATR 80 and the TVI 8002 nozzles were tested at four pressure values: 0.3, 0.5, 1.0, and 1.5 MPa; the AVI 11003 nozzle was tested at 0.3 and 0.5 MPa. The drop size measurement technique was based on the liquid immersion method by using a custom-made test bench; spray quality parameters were computed by means of suitable functions written in R language. Results showed that an increase in working pressure caused an increase in drop pulverization regardless of the type of nozzle, and drop pulverization was higher for the turbulence nozzle than for the two air induction nozzles. Based on skewness and kurtosis values, the theoretical gamma distribution was the most adapt to fit the experimental data. The scale parameter showed a decreasing trend with the increase in the pressure, a clear index of higher drop pulverization.

Quantity and quality evaluation of the Cellulose Nanocrystalline Production from Date Palms (Phoenix Dactylifera L.) by Hydrolysis Method

In this research, cellulose was first extracted from Date palm leaves and it was then converted to the cellulose nanocrystal by acid hydrolysis of the nanocrystal cellulose. In this research, the effect of 3 temperature parameters (at 30, 45 and 60 ° C) and 3 time (at 45, 60 and 120 minutes on three levels) on the quality and quantity of nanocrystals from palm tree leaves were investigated. Several experiments with infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and particle size measurement (PSA) techniques were used to analyze qualitative and quantitative qualities such as factor groups, morphology, diameter distribution and shape Nanocrystals have been studied. The results showed that more severe treatments produce smaller Nano-crystals. The results of the Particle Measurement (PSA) showed that most extractive particles have dimensions ranging from 5 to 100 nanometers and are mostly 30 nm. Also, the results (XRD) showed that extractive nanocellulose had a purity of between 70 and 80 percent. In this study, the time of 60 minutes and 60 Celsius temperature were identified as the best factors among similar factors. In this treatment, 50% of particles have a mean diameter of 1.37 nm. The maximum and minimum diameter of the observed particles was 6.34 and 0.41 nm, respectively. Also, the results of cellulose extraction from palm leaf showed that increasing the temperature in the ligninization and coloring step increases the purity of the extracellular cellulose. In addition, the increase in temperature resulted in a decrease in the amount of cellulose produced, possibly due to the increased effect of chemical treatments and cellulose degradation.

Drop size measurement techniques for sprays: Comparison of image analysis, phase Doppler particle analysis, and laser diffraction

Four different methods for measuring droplet size distributions are evaluated: the Image Analysis VisiSizer technique, a stroboscopic imaging method developed in-house, phase Doppler particle analysis (PDPA), and laser diffraction (Malvern Spraytec). We find that the larger the droplets, the bigger the differences between the results obtained by the different methods. The Image Analysis VisiSizer technique yields results that are comparable with those of the stroboscopic imaging method, provided that the raw Visisizer data are used, as the VisiSizer software makes corrections that can skew the results. Our measurements confirm how the limitations of PDPA can influence its outcomes; the presence of air bubbles inside droplets will cause PDPA to mistake them for smaller droplets. The fact that PDPA reports no droplets larger than 1200 μm might be caused by large drops often not being spherical. The results of the laser diffraction technique are influenced by its fitting method to obtain the droplet size distribution and by overestimation of the number of small droplets due to their low velocity and thus higher concentration in the sample volume. Our results emphasize the need for selecting the size measurement technique to fit the physical nature and expected range of droplet parameters.

Establishing the applicability of the laser diffraction technique for the graphene oxide platelets lateral size measurements

In this paper, basing on the thorough comparison of the size measurement results obtained by Laser Diffraction (LD) and microscopic methods, we demonstrate the LD method to provide reliable and accurate data on the lateral size of two-dimensional graphene oxide (GO) platelets. Taking cue from the experimental study and theoretical calculations of scattering patterns, model accounting for arising of diffraction pattern that can be correctly processed with common LD instrumentation is suggested.

Theoretical and Experimental Gas Volume Quantification of Micro- and Nanobubble Ultrasound Contrast Agents.

The amount of gas in ultrasound contrast agents is related to their acoustic activity. Because of this relationship, gas volume has been used as a key variable in normalizing the in vitro and in vivo acoustic behavior of lipid shell-stabilized bubbles with different sizes and shell components. Despite its importance, bubble gas volume has typically only been theoretically calculated based on bubble size and concentration that is typically measured using the Coulter counter for microbubbles and nanoparticle tracking analysis (NTA) for nanoscale bubbles. However, while these methods have been validated for the analysis of liquid or solid particles, their application in bubble analysis has not been rigorously studied. We have previously shown that resonant mass measurement (RMM) may be a better-suited technique for sub-micron bubble analysis, as it can measure both buoyant and non-buoyant particle size and concentration. Here, we provide validation of RMM bubble analysis by using headspace gas chromatography/mass spectrometry (GC/MS) to experimentally measure the gas volume of the bubble samples. This measurement was then used as ground truth to test the accuracy of theoretical gas volume predictions based on RMM, NTA (for nanobubbles), and Coulter counter (for microbubbles) measurements. The results show that the headspace GC/MS gas volume measurements agreed well with the theoretical predictions for the RMM of nanobubbles but not NTA. For nanobubbles, the theoretical gas volume using RMM was 10% lower than the experimental GC/MS measurements; meanwhile, using NTA resulted in an 82% lower predicted gas volume. For microbubbles, the experimental gas volume from the GC/MS measurements was 27% lower compared to RMM and 72% less compared to the Coulter counter results. This study demonstrates that the gas volume of nanobubbles and microbubbles can be reliably measured using headspace GC/MS to validate bubble size measurement techniques. We also conclude that the accuracy of theoretical predictions is highly dependent on proper size and concentration measurements.

Sanding and analysis of dust from nano-silica filled composite resins for stereolithography

The aim of this work was to assess whether with high amounts of nano-silica filled cured resins release nano-particles upon their abrasion, as this could form an occupational health risk and require specific safety measures.A standardised abrasion stress method involving a Taber linear abrasion apparatus (Model 5750) has been applied to the filled polymer samples. This linear abrasion apparatus simulates the mechanical solicitation, i.e. abrasion. Various particle size measurement techniques were applied to assess the size distribution and the quantity of particles released.Observations of airborne particle from abrasion tests are consistent with TEM characterization of the nanomaterials before any tests. Abrasions of both samples (called here ‘1’ and ‘2’) gave rise to emissions. For sample 1, a few ‘dust’ particles and micronic particles are observed. For sample 2, despite a track on the sample, no detectable micronic particles and very few ‘dust’, particles are detected. As a result, we can state there were effective abrasions which gave rise to a low emission (sample 1) and a very low emission (sample 2) under the detection limits of particle sizing and counting, for the last case.The emission of particles upon Taber test abrasion is extremely low (less than 8 particles per cm3) and for one of the samples at the level of the detection limit. Moreover, the size of these particles is generally larger than 100nm.

Impact of coagulant type and magnetic ion exchange (MIEX) pre-treatment on floc strength and structure at the Kluizen Water Treatment Plant, Belgium

Drinking water supplied to the community should be free from Disinfection ByProducts (DPB). DPB occurs when organic matter is present in surface water and reacts with chlorine. Conventional coagulation and flocculation processes have been used in water treatment plants to remove organic matters from raw water. Recently, Magnetic Ion Exchange (MIEX) followed by coagulation and flocculation has started to attract attention since it improves natural organic matter removal and decreases coagulant demand. The efficiency of NOM removal and downstream processes not only depends on the prior removal process of organic matter but also on the structure , size and strength of flocs formed in the coagulation process as well. This study aims at comparing (1) floc structures (i.e. floc sizes, floc strength, and fractal dimensions) generated from coagulation of raw water and (2) water pre-treated with magnetic ion exchange obtained from Kluizen water treatment plant (Kluizen, East-Flanders, Belgium). The floc sizes during growth, breakage and re-growth were measured using (laser) light scattering (Malvern Mastersizer 2000), coupled with jar test equipment. The strength of flocs was evaluated by empirically relating the floc size to the increased shear rate applied. The results show that pre-treated water coagulated with all the coagulants produces flocs with larger sizes compared to the flocs generated from raw water. For both water types, FeCl3 gave better recoverability after breakage than PACl and AlCl3. After pre-treatment, the floc size was increased by 19%, 63% and 64% forthe coagulants such as PACl, AlCl3, and FeCl3, respectively. Coagulation process with PACl generated flocs with higher fractal dimension and lower strength constants which indicates that flocs generated is strong and compacted micro-flocs. The floc size measurement techniques and coagulation system were found to have an impact on the resulting floc sizes.

A Comparison between Anodizing and EBSD Techniques for Primary Particle Size Measurement

Proper understanding and knowledge of primary particle or grain size is of paramount importance in manufacturing processes as it directly affects various properties including mechanical behavior. Application of optical microscopy coupled with etching techniques has been used conventionally and in conjunction with color metallography (polarized microscopy) has been the preferred method for grain size measurement. An advanced technique as an alternative to light microscopy is using electron backscatter diffraction (EBSD). A comparison is made between these two techniques using Al-7Si alloy produced with various casting techniques to highlight the cost and time of the sample preparation and analysis for both techniques. Results showed that color metallography is certainly a faster technique with great accuracy and a much cheaper alternative in comparison with EBSD.

Revised approach for the prediction of functional size of mobile application

Mobile applications affect our everyday activities and have become more and more information centric. Effort estimation for mobile application is an essential factor to consider in the development cycle. Due to feature complexities and size, effort estimation of mobile applications poses a continued challenge for developers. This paper attempts to adapt COSMIC Function Point and Unified Modeling Language (UML) techniques to estimate the size of a given mobile application. The COSMIC concepts capture data movements of the functional processes whereas the UML class analyzes them. We utilize the Use Case Diagrams, sequence diagrams and class diagrams for mapping the Function user requirements for sizing mobile applications. We further present a new size measurement technique; Unadjusted Mobile COSMIC Function points (UMCFP) to get the functional size of mobile application using Mobile Complex Factors as an input. In this study eight mobile applications were analyzed using UMCFP, Function Point Analysis and COSMIC Function Point. The results were compared with the actual size of previous Mobile application projects.

3D Shape Analysis of Powder for Laser Beam Melting by Synchrotron X-ray CT

The quality of components made by laser beam melting (LBM) additive manufacturing is naturally influenced by the quality of the powder bed. A packing density &lt;1 and porosity inside the powder particles lead to intrinsic voids in the powder bed. Since the packing density is determined by the particle size and shape distribution, the determination of these properties is of significant interest to assess the printing process. In this work, the size and shape distribution, the amount of the particle’s intrinsic porosity, as well as the packing density of micrometric powder used for LBM, have been investigated by means of synchrotron X-ray computed tomography (CT). Two different powder batches were investigated: Ti–6Al–4V produced by plasma atomization and stainless steel 316L produced by gas atomization. Plasma atomization particles were observed to be more spherical in terms of the mean anisotropy compared to particles produced by gas atomization. The two kinds of particles were comparable in size according to the equivalent diameter. The packing density was lower (i.e., the powder bed contained more voids in between particles) for the Ti–6Al–4V particles. The comparison of the tomographic results with laser diffraction, as another particle size measurement technique, proved to be in agreement.

Hydrodynamics and scale-up of bubble columns in the heterogeneous regime: Comparison of bubble size, gas holdup and liquid velocity measured in 4 bubble columns from 0.15 m to 3 m in diameter

The development of CFD models coupled with Population Balance is a very promising topic concerning multiphase reactors. In the case of bubbly flows and bubble columns, a serious lack of local hydrodynamic characterizations still harms development and validation of relevant models. To fill partially this gap, a new bubble size measurement technique, previously introduced by Maximiano Raimundo et al. (2016), has been applied on a very wide range of bubble column diameters (from 0.15 m to 3 m) and superficial gas velocities (from 0.06 m/s to 0.35 m/s). Size measurements have been coupled with others concerning gas holdup and axial liquid velocity, in order to provide an experimental database allowing to clarify the scale-up rules and to assist future modelling works. Average bubble sizes have been measured as globally similar at every scale. Measured holdup and average liquid velocity confirm already reported behaviours at lower column diameters. Liquid velocity fluctuations also follow self-similar radial profiles and are proportional to the average liquid velocity at the centre of the column leading to a strong turbulence intensity. The fact that the quantity (gD)1/2 appears as a natural velocity scale and the presence of strong gas-holdup gradients underline the similarity between bubble columns operated heterogeneous regime and free thermal convection in pipes.

Challenging the Current Concept of Critical Glenoid Bone Loss in Shoulder Instability: Does the Size Measurement Really Tell It All?

Background: Bone loss at the anterior glenoid rim is a main reason for failure of soft-tissue based surgical stabilization procedures in patients with anterior shoulder instability. Purpose: To evaluate the capability of conventional glenoid bone loss measurement techniques to provide an adequate estimation of the actual biomechanical effect of glenoid defects. Study Design: Descriptive laboratory study. Methods: Thirty consecutive patients with unilateral anterior shoulder instability and varying degrees of glenoid defect were included. Patient-specific computer tomography–based 3-dimensional shoulder models of the affected and unaffected sides were created. The bony shoulder stability ratio (SR) was determined in various potential dislocation directions with finite element analysis. Values obtained from conventional glenoid defect size measurement techniques (Pico and Sugaya) were correlated with the finite element analysis results. Additionally, a mathematical model was developed to theoretically analyze the correlation between glenoid defect size measurements and the SR. Results: The authors found substantial interindividual differences of the SR of the unaffected shoulders in all directions of measurement. Bone loss at the anterior glenoid rim significantly reduced the SR in the 2-o’clock (P = .011), 3-o’clock (P < .001), and 4-o’clock (P < .001) directions referring to a right shoulder. The correlation between the defect size measurements and the SR for the 2-o’clock (rho = −0.522 and −0.580), 3-o’clock (rho = −0.597 and −0.580), and 4-o’clock (rho = −0.527 and −0.522) directions was statistically significant. However, it showed only moderate strength and was nonlinear as well as dependent on the inherent shape of the concavity. As shown by the mathematical model, bone loss has the most considerable effect at the edge of the glenoid rim, and an increasingly concave-shaped glenoid leads to an increase in loss of SR provoked by the same extent of bone loss. Conclusion: Current glenoid bone loss measurements are unable to provide an adequate estimation on the actual biomechanical effect of glenoid defects because (1) the relation between the glenoid defect size and its biomechanical effect is nonlinear and (2) patients with shoulder instability have constitutional biomechanically relevant glenoid concavity shape differences. Clinical Relevance: These findings challenge the current concept of setting a general threshold for critical glenoid bone loss, which requires bony reconstruction surgery.