Laser Diffraction Method Research Articles

Chloride gradient is the driving force for ammonia/ammonium influx in human red blood cells

Ammonium/ammonia (AM) Rhesus transporters are expressed in tissues involved in AM generation, secretion and excretion, however, the physiological role of erythroid RhAG glycoprotein is not fully defined yet. AM concentration in red blood cells (RBCs) is approximately three times higher than in plasma and RBCs are the only blood cells that swell and lyse in isotonic ammonium (NH4+) buffer indicating that AM is transported inside the cell. Two main possible mechanisms of AM transport, including diffusion and active transport, are described, however, the real driving force for AM influx in RBCs is still under debate. RhAG and anion exchanger 1 (AE1, band 3, Cl-/HCO3--exchanger) form a structural complex in RBC membrane therefore we hypothesized that AE1 might be involved in AM influx in RBCs via the interplay with RhAG, and suggested that RhAG uses chloride (Cl-) gradient mediated by AE1 to import NH4+ against the gradient. Washed human RBCs were analyzed by flow cytometry, spectrophotometry and laser diffraction methods. For the evaluation of the interplay between RhAG and AE1 transporters HEPES buffer (in mM: NaCl, 140; KCl, 2; HEPES, 10, MgCl2, 2; Glucose, 5) and isotonic NH4+ buffer (in mM: NH4Cl, 140; KCl, 2; HEPES, 10; MgCl2, 2; Glucose, 5) were used. For the analysis of the role of Cl-gradient NaCl and NH4Cl were substituted by sodium glutamate and ammonium glutamate. Calcein-AM was used for cell vitality registration, hemoglobin (Hb) forms were analyzed spectrally, AM import was assessed by enzymatic and colorimetric AM assay kits, AE1 was inhibited by DIDS. In isotonic NH4+ buffer RBCs rapidly swelled and lysed within 3min at 37°C. The addition of AE1 substrate HCO3- (25mM) to isotonic NH4+ buffer increased the cell swelling rate 49±5 fold (n=11, Leven's test p>0.05, Tukey HSD post hoc, p<0.001). NH4+ import in media containing HCO3- increased by 74±11% (n=9, Leven's test p<0.05, Tamhane T2 post hoc, p<0.001). AE1 inhibition completely prevented hemolysis in isotonic NH4+ buffer and decreased NH4+ import in RBCs by 66±9% (n=9, Leven's test p<0.05, Tamhane T2 post hoc, p<0.001). The lack of Cl- gradient in ammonium glutamate and sodium glutamate isotonic buffers had no effects on cell viability (esterase activity) or Hb conformation. In isotonic ammonium glutamate buffer Cl- substitution prevented cell swelling and completely inhibited hemolysis in the same manner as AE1 inhibition by DIDS in NH4+buffer. AM import in conditions lacking Cl- gradient decreased by 62±11% (n=9, Leven's test p<0.05, Tamhane T2 post hoc, p<0.001) which is consistent with AE1 inhibition data. Our data clearly indicated that RhAG and AE1 are functionally connected, and AE1-mediatedCl-gradient drives RhAG-facilitated AM transport in RBCs. Therefore, we suggest that NH4+ is imported in human RBCs against its gradient by a secondary active transport mechanism, rather than via facilitated diffusion. Taken together our data revealed the new mechanism of AM transport against the gradient in RBCs and suggested that RBCs in addition to main functions are involved in the AM concentration regulation in plasma.

Particle Size Distribution of Various Soil Materials Measured by Laser Diffraction—The Problem of Reproducibility

Particle size distribution is an important soil parameter—therefore precise measurement of this characteristic is essential. The application of the widely used laser diffraction method for soil analysis continues to be a subject of debate. The precision of this method, proven on homogeneous samples, has been implicitly extended to soil analyses, but this has not been sufficiently well confirmed in the literature thus far. The aim of this study is to supplement the information available on the precision of the method in terms of reproducibility of soil measurement and whether the reproducibility of soil measurement is characterized by a normal distribution. To estimate the reproducibility of the laser diffraction method, thirteen various soil samples were characterized, and results were analysed statistically. The coefficient of variation acquired was lowest (3.44%) for silt and highest for sand (23.28%). Five of the thirteen tested samples were characterized by a normal distribution. The fraction content of eight samples was not characterized by normal distribution, but the extent of this phenomenon varied between soils. Although the laser diffraction method is repeatable, the measurement of soil particle size distribution can have limited reproducibility. The main cause seems to be small amounts of sand particles. The error can be amplified by the construction of the dispersion unit. Non-parametric statistical tests should be used by default for soil laser diffraction method analysis.

Measurement of soil dry aggregate size distribution using the laser diffraction method

Aggregate size distribution of soil is an important parameter to describe soil properties. For many years, the size of soil aggregates has been measured using the dry sieving method. During sieving, particularly less-stable aggregates may have broken down. However, apart from the sieve method, there was no method enabling direct measurement of aggregates on a dry basis. The modification of the measurement system presented in this paper allows such measurements to be conducted using the laser diffraction method. The average coefficient of variation of the proposed method was about 2.6 %.

Graphene Oxide Chemistry Management via the Use of KMnO4/K2Cr2O7 Oxidizing Agents.

In this paper, we propose a facile approach to the management of graphene oxide (GO) chemistry via its synthesis using KMnO4/K2Cr2O7 oxidizing agents at different ratios. Using Fourier Transformed Infrared Spectroscopy, X-ray Photoelectron Spectroscopy, and X-ray Absorption Spectroscopy, we show that the number of basal-plane and edge-located oxygenic groups can be controllably tuned by altering the KMnO4/K2Cr2O7 ratio. The linear two-fold reduction in the number of the hydroxyls and epoxides with the simultaneous three-fold rise in the content of carbonyls and carboxyls is indicated upon the transition from KMnO4 to K2Cr2O7 as a predominant oxidizing agent. The effect of the oxidation mixture’s composition on the structure of the synthesized GOs is also comprehensively studied by means of X-ray diffraction, Raman spectroscopy, transmission electron microscopy, atomic-force microscopy, optical microscopy, and the laser diffraction method. The nanoscale corrugation of the GO platelets with the increase of the K2Cr2O7 content is signified, whereas the 10–100 μm lateral size, lamellar, and defect-free structure is demonstrated for all of the synthesized GOs regardless of the KMnO4/K2Cr2O7 ratio. The proposed method for the synthesis of GO with the desired chemistry opens up new horizons for the development of graphene-based materials with tunable functional properties.

Comparison between hydrometer and laser diffraction methods in the determination of clay content in fine-grained soils

Clay content is the main characterizing parameter when classifying fine-grained soils. Hydrometer method (HD) is commonly used in geotechnics to obtain the grain size distribution properties of fine-grained soils. However, this test is laborious and time consuming as compared to alternative methods such as laser diffraction (LD). In this study, a comparison between the results for clay content of 19 samples from different locations in Finland using HD and LD methods was carried out aiming at obtaining a mathematical expression that allows to transform LD measurements into HD results. The results were statistically compared showing significant differences between the results of these two techniques and underestimation of the clay content by the LD method was observed. Based on the results, the reliability of the laser method in the determination of clay content is discussed.

Comparison of plasma and pulmonary availability of chlorogenic acid, forsythiaside A and baicalin after intratracheal and intravenous administration of Shuang-Huang-Lian injection

Ethnopharmacological relevanceThe off-label nebulization of Shuang-Huang-Lian (SHL) injection is often utilized to treat respiratory tract infections in China. However, the pulmonary biopharmaceutics of SHL was generally unknown, limiting the rational selection of therapeutic dose and dose frequency. Aim of the studyTo characterize the size distribution of nebulized aerosols and to compare the pharmacokinetics and the lung distribution of three chemical makers of SHL, chlorogenic acid (CHA), forsythiaside A (FTA) and baicalin (BC), after intratracheal and intravenous administration of SHL to rats. Materials and methodsThe droplet size distribution profiles over nebulization process were dynamically monitored using a laser diffraction method whereas the levels of CHA, FTA and BC in plasma, lung tissues and bronchoalveolar lavage fluids (BALF) were determined by a validated LC-MS/MS assay. The pulmonary anti-inflammatory efficacy was evaluated using a lipopolysaccharide (LPS) induced lung inflammation model as indicated by the level of tumor necrosis factor-α (TNF-α) in BALF. ResultsThe nebulization of SHL showed good inhalability and allowed the aerosols to reach the upper or lower respiratory tract dependent on the performance of selected nebulizers. Following intratracheal administration of SHL at different doses, CHA, FTA and BC were absorbed into the bloodstream with the mean absorption time being 67.5, 63.5 and 114 min, respectively, rendering mean absolute bioavailabilities between 42.4% and 61.4% roughly independent of delivered dose. Relative to the intravenous injection, the intrapulmonary delivery increased the lung-to-plasma concentration ratios of CHA, FTA and BC by more than 100 folds and markedly improved the lung availability by 563–676 folds, leading to enhanced and prolonged lung retention. The production of TNF-α in BALF was decreased by ~50% at an intratracheal dose of 125 μL/kg SHL to LPS-treated mice. ConclusionThe nebulization delivery of SHL is a promising alternative to the intravenous injection for the treatment of respiratory tract infections.

Impact of co-processed excipient particles solidity and circularity on critical quality attributes of orodispersible minitablets

The selection of appropriate functional co-processed excipient (CPE) is a crucial stage in orodispersible minitablets (ODMTs) development. This paper aimed to identify the most important morphological attributes influencing the flowability and homogeneity of powder mixtures and minitablets final quality. Our research included the use of the laser diffraction method, the microscopic automated imaging technique and a flowability tester. All powder parameters examined were divided into two groups: those affecting mixture homogeneity or flowability. A Pearson's correlation matrix revealed a strong relationship between both, especially in terms of solidity-circularity and convexity-circularity pairs (r = −0.71, p = 0.010 and r = 0.93, p = 0.000 respectively). An analysis of model mixtures confirmed that high solidity values of the CPE support final mixture homogeneity and accordingly high circularity values support its flowability. In conclusion, solidity and circularity were indicated as the most critical morphological parameters, which have to be analyzed to define the best possible ODMTs formulation.

Digital microscopic image application (DMIA), an automatic method for particle size distribution analysis in waste activated sludge.

An important physical property in environmental samples is particle size distribution. Several processes exist to measure particle diameter, including change in electrical resistance, blocking of light, the fractionation of field flow and laser diffraction (these being the most commonly used). However, their use requires expensive and complex equipment. Therefore, a digital microscopic imaging application (DMIA) method was developed adapting the algorithms used in the helminth egg automatic detector software coupled with a neural network (NN) and Bayesian algorithms. This allowed the determination of particle size distribution in samples of waste activated sludge (WAS), recirculated sludge (RCS), and pre-treated sludge (PTS). The recirculation and electro-oxidation pre-treatment processes showed an effect in increasing the degree of solubilization, decreasing particle size and breakage factor with ranges between 44.29%, and 31.89%. Together with a final NN calibration process, it was possible to compare results. For example, the 90th percentile of equivalent diameter value obtained by the DMIA with the corresponding result for the laser diffraction method. DMIA values: 228.76 μm (WAS), 111.18 μm (RCS), and 84.45 μm (PTS). DMIA processing has advantages in terms of reducing complexity, cost and time, and offers an alternative to the laser diffraction method.

Stability of Aggregates Made by Earthworms in Soils with Organic Additives

Earthworm activity is a key factor in creating soil aggregates, but introduced organic matter and abiotic factors are also equally important. The purpose of this study was to investigate the stability of aggregates made by earthworms in soils with organic additives. Additionally, the two aggregate stability measurement methods were compared: (i) the wet-sieve method and (ii) the laser diffraction method. A six-month container experiment containing sixteen treatments and controls were made. Each treatment included one of four types of soil texture: sand, loam, silty loam and clay, and one of four additives: straw, peat, compost and compost with added microorganisms. To each treatment, six earthworms were added, two each of species commonly occurring in Polish soils: Dendrodrilus rubidus, Aporrectodea caliginosa and A. rosea. This study confirmed that earthworm activity was the factor favoring aggregate formation. In terms of the investigated organic additives, the efficiency of aggregate creation was as follows: compost with active bacteria, compost, peat and straw. Nevertheless, earthworms alone, without the addition of an organic additive, did not form permanent aggregates. The wet sieving and laser diffractometry methods of measuring aggregate stability were comparable for silty, clayey and loamy soils.

Analyzing ophthalmic suspension particle size distributions using laser diffraction: Placebo background subtraction method

The current study demonstrated that the presence of excipients can interfere with the measurement of particle size distribution (PSD), a critical quality attribute of ophthalmic suspensions, by laser diffraction (LD) and that a placebo background subtraction approach can eliminate the impact of excipients on the PSD measurement. Commercially available loteprednol etabonate and brinzolamide ophthalmic suspensions were used as model suspensions. The impact of excipients in these formulations on the LD measurements was determined using a one-factor-at-a-time experimental design approach, using National Institute of Standards and Technology (NIST) traceable polystyrene particle size standards as references. Among the evaluated excipients, polymers containing polyacrylic acid were found to interfere with the PSD analysis by creating the LD signals correspond to particles ranging from a few micrometers to a hundred micrometers in size. As a result, the measured PSD of active pharmaceutical ingredient (API) particles in the formulation overlapped with or superimposed on the excipient PSD signal, leading to erroneous interpretation of the API particle size. Additionally, dispersion of brinzolamide particles in unsaturated solutions led to rapid dissolution of brinzolamide particles during the measurement, resulting in underestimation of the particle size range. Here, a placebo background subtraction approach was developed to eliminate the interference of the excipients. This newly developed LD method was also evaluated using orthogonal methods, including polarized light microscopy and scanning electron microscopy (SEM). The strategy used in this study to eliminate the interference of excipients may also be useful for other heterogeneous dispersions where excipient interference may be of concern.

Applicability of laser diffraction method for soil particle size distribution analysis of five soil orders in the water erosion region of China

Soil particle size distribution (PSD) is a critical parameter for soil loss estimation in many water erosion models. The laser diffraction method (LDM) has been increasingly applied for soil PSD determination in recent decades, and its applicability and reliability need systematical examinations. The objective was to evaluate the performance of LDM for PSD determination of five soil orders in the water erosion region of China relative to the traditional sieve-pipette method (SPM). A total of 465 soil samples were collected in the five water erosion subregions of China, which correspond to five soil orders of Mollisols, Alfisols, Entisols, Inceptisols, and Oxisols. All the samples were analyzed with LDM for the four size fractions widely employed in water erosion models (i.e., 100 to 2,000, 53 to 100, 2 to 53, and &lt;2 μm), and the corresponding results were compared to those obtained by SPM. The comparisons show varying results between LDM and SPM for the sand content, or the two sand-sized fractions of 100 to 2,000 and 53 to 100 μm. LDM consistently overestimated the silt content and underestimated the clay fraction, yet the magnitude of either the overestimation or underestimation varied among soil orders. The PSD discrepancies shifted the textural classes of 44.8% to 96.2% of the soil samples and, on average, increased the soil erodibility <i>K</i> factor by 0.010 to 0.034 t MJ^–1 h mm^–1 for different soil orders. The optimal clay/silt and silt/sand boundaries of LDM were derived to match the size fractions measured by SPM. Nevertheless, except for the silt/sand boundary of 58.2 μm for one soil order, each of the other threshold boundaries held a Lin’s concordance correlation coefficient less than 0.8, suggesting moderate or poor agreement between LDM and SPM. Linear regression models were also established to convert the four size fractions between the two methods for all the samples as well as for each soil order. However, not all the conversion models were statistically significant at the level of 0.05. Those that were significant varied among soil orders for each size fraction. These findings hold important practical implications for soil PSD determination and water erosion modeling in China and elsewhere.

Using Different Approaches of Particle Size Analysis for Estimation of Water Retention Capacity of Soils: Example of Keszthely Mountains (Hungary)

PSD (particle size distribution) is a key factor affecting soil hydro-physical properties (e.g. hydraulic conductivity and water retention), which makes its determination essential. Climate change increases the importance of water retention and permeability as extreme weather events can severely impair the water supply of drought-sensitive vegetation. The amount of water in soils is expected to decrease. The modified Thornthwaite model considers soil properties such as root depth, topsoil layer thickness and particle size distribution (silt and clay fraction) of soil particles combined with the most significant soil properties. At the beginning of the research, we developed a laser diffraction method to replace the standard based “pipette” sedimentation method. The theoretical background of laser diffraction measurements is already known, but their practical application for estimating soil water retention capacity is still poorly understood. The pre-sieving of soil aggregates, the pre-treatment (disaggregation and dispersion) of the samples greatly influence the obtained results. In addition to the sedimentation method, laser diffraction measurements (Malvern Mastersizer 3000) were applied with three variants of pre-treatment. For comparison, the results of a Leptosol, a Cambisol, and a Luvisol were prepared for the first modified Thornthwaite water balance model. Significant differences appeared, especially during drought periods, which could be a basis for studying soil drought sensitivity. The development of our method can estimate the water retention capacity of soil, which could support adaptive forest management plans against climatic and pedological transformations.

Variation In Textural Properties Of Aplitic Kaolin From Kinta Valley

Textural properties are among one of the fundamental characteristics especially important to be understood before suitable application(s) of a kaolin can be determined as they have direct influence on the other properties such as plasticity, brightness, firing and rheological behavior. This paper presents an investigation on the textural properties of aplitic kaolin from Kinta Valley. Two degritted kaolin samples from different location of Kinta Valley were measured for their particle size distribution by laser diffraction method. The samples were then classified into different size fractions followed by examination of their morphological property by various techniques which X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and field emission scanning electron microscope (FESEM). Generally, the kaolin can be classified into two different types based on the fine fraction content which may be consists of; i) delaminated platy kaolinite, or ii) tubular shaped halloysite. These fine fractions however constitute only to minor amount or not more than 12 % of the clays, as both clay consist predominantly of coarse book like kaolinite stacks. The degree of crystallinity of kaolinite samples shows a positive correlation to its particle size during examination by XRD, but FTIR spectrum shows a high degree of crystallinity for all kaolinite samples regardless of their particle size. Slight presence of halloysite is sufficient to give an adverse effect on the clay crystallinity index measured from XRD pattern. Sorting of the clay into different size and morphological fraction creates a product with less variation in properties between individual particles, and with more potential for tailoring or engineering of their properties.

ASSOCIATION BETWEEN ROOT COMPLEXITY OF Rhizophora apiculata AND SEDIMENTATION AT PANTAI KELANANG, SELANGOR

Roots play important roles in tree structural adaptation and accumulation of nutrients during growth. This is particularly critical for mangrove trees that facing strong current and weak based for implantation in the sand. However, how the complexity of mangrove roots contributes to structural adaptation and affect sedimentation remains unelucidated. In this study, the complexity of Rhizophora apiculata’s roots influence the sedimentation under the root structures and at the walkway area in Pantai Kelanang, Morib were investigated. The complexity of R. apiculata pneumatophores was computationally analyzed. The sediment composition was measured using a wet-sieve method and laser diffraction method. The correlative analysis shows that no definite pattern between angles and lengths of R. apiculata roots. Assessment of sediment composition shows significant differences between walkways and under the roots. There is a high accumulation of organic matter and sand in sediment samples from under the roots. While the walkway has a high accumulation of clays and silt than others. Mathematical scoring reveals a positive association between root complexities with the accumulation of organic matters and sand in both areas. While sand and clay accumulation are inversely associated.

Recommendations for crushing Circadin® (melatonin) tablets for safe and reliable delivery via pediatric nasogastric tubes

Melatonin is an important drug in pediatric medicine which often requires delivery through a narrow bore nasogastric tube (e.g. FR6; 1300 µm internal diameter) for patients that cannot swallow tablets. Although Circadin® 2 mg tablets are often crushed for nasogastric delivery, there is an absence of evidence for the effectiveness of different methods for producing powders that can be administered without risk of blocking nasogastric tubes. Our aim was to develop a robust protocol for crushing Circadin tablets and suspending the powder for safe administration via paediatric nasogastric tubes. Circadin tablets were crushed using four different tablet crushers. For comparison, a pestle and mortar and tablespoon were also used to crush tablets as these techniques are also used in clinical practice. The particle size of powders resulting from different crushing maneuvers was evaluated using sieve analysis, laser diffraction and image-based sizing methods. For all the tablet crushers, five operations produced powders with irregular-shaped individual particles less than 500 µm diameter. A protocol termed ‘King’s 5-5-5′ was developed for tablet crushers: powder obtained after 5 crushes was suspended in 5 mL water and delivered through NG tubes with pre and post-administration flushing with 5 mL water. This protocol is simple, low cost, uses readily available materials and enables the safe and reliable delivery of melatonin to paediatric patients without the fear of blocking nasogastric tubes.

Soil particle size range correction for improved calibration relationship between the laser-diffraction method and sieve-pipette method

Particle size fraction (clay, silt, and sand) is an important characteristic that influences several soil functions. The laser-diffraction method (LDM) provides a fast and cost-effective measurement of particle size distribution, but the results usually differ from those obtained by the traditional sieve-pipette method (SPM). This difference can persist even when calibration is applied between the two methods. This partly relates to the different size ranges of particles measured by the two methods as a result of different operational principles, i.e., particle sedimentation according to Stokes’ Law vs. Mie theory for laser beam scattering. The objective of this study was to identify particle size ranges of LDM equivalent to those measured by SPM and evaluate whether new calibration models based on size range correction can be used to improve LDM-estimated particle size fractions, using 51 soil samples with various texture collected from five soil orders in New Zealand. Particle size distribution was determined using both LDM and SPM. Compared with SPM, original data from LDM underestimated the clay fraction (< 2 μm), overestimated the silt fraction (2–53 μm), but provided a good estimation of the sand fraction (53–2 000 μm). Results from three statistical indices, including Pearson's correlation coefficient, slope, and Lin's concordance correlation coefficient, showed that the size ranges of < 2 and 2–53 μm defined by SPM corresponded with the < 5 and 5–53 μm size ranges by LDM, respectively. Compared with the traditional calibration (based on the same particle size ranges), new calibration models (based on the corrected size ranges of these two methods) improved the estimation of clay and silt contents by LDM. Compared with soil-specific models (i.e., different models were developed for different soils), a universal model may be more parsimonious for estimating particle size fractions if the samples to be assessed represent multiple soil orders.

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.

The Ways to Develop Soil Textural Classification for Laser Diffraction Method

The existing classifications of soil texture are based on the sedimentation data. The aim of this article is to consider the ways to develop soil textural classification on the basis of particle-size distribution (PSD) data obtained by the laser diffraction method. A detailed comparison of PSD data obtained by the classical pipette method and the method of laser diffractometry has been performed. We have shown the reproducibility of the laser diffraction method and the effect of the oxidation stage on the soil texture class. This study is based on eight genetic soil types (overall, 32 full-profile soil pits) forming a zonal soil sequence from Podzols (Subpolar Urals) to ferrallitic soil (southwest Oceania) and differing in their mineralogical compositions, textures, and elementary pedogenetic processes. The direct use of the Kachinskii and USDA classifications with the data of the laser diffraction method leads to mistakes in determining the soil texture class in 43 and 65% of cases, respectively. The increasing complexity of recalculation, introduction of new variables, and accounting for interlaboratory errors allow us to determine correctly the texture class according to the Kachinskii and USDA classifications in no more than 70 and 72% of soil samples, respectively. The most simple and effective approach to solve the classification problem for the laser diffraction method is to calibrate existing classifications directly on the basis of data on soil samples, for which the texture class was determined by the field method.

Comparison of Hydrometer Analysis and Laser Diffraction Method for Measuring Particle and Floc Size Distribution Applied to Fine Coal Refuse

Abstract Traditional grain size distribution measurement techniques assume that the measured particle diameters are of individual grains. However, for suspended particulate materials, particles may be dispersed or associated in flocs. Further, particle-level associations depend on the surrounding fluid chemistry, which may change over time. The purpose of this study is to compare two different methods of grain size analysis for detecting particle and floc sizes in suspensions of fine coal refuse (FCR): hydrometer analysis, the well-known traditional method, and laser diffraction, a lesser known method. The influence of background solution—flocculant, dispersant, or distilled water—on the apparent grain size of FCR was also investigated. Analogous slurry suspensions made from a well-characterized kaolin were analyzed for comparison. Results from the grain/floc size analysis indicate that there are several advantages of laser diffraction over hydrometer analysis including a short measurement period, small sample size requirement, and the ability to measure a wide range of particle sizes in the same analysis. Moreover, this study highlights the ability of the particle size analyzer (PSA) to accurately measure changes in apparent particle size over time for the same suspension and thereby indicate the presence of flocs. Finally, the PSA has the capability of capturing dynamic particle interactions—flocculation and deflocculation—in real time.

Mechanical high-energy treatment of TiNi powder and phase changes after electrochemical hydrogenation

The paper presents the results obtained for the effect of ball milling of Ti–Ni powder, which is close in composition to the equiatomic one, on electrochemical hydrogenation. It is shown that the average size of the powder particles measured by BET and laser diffraction methods is found to reduce during milling, while the average size of the powder particles measured by SEM changes to attain its minimum within 30-s milling due to destruction and subsequent aggregation of particles. The powder in its initial state consists of a mixture of TiNi (austenite, martensite), Ti2Ni, and TiNi3 phases, and after ball milling, an X-ray amorphous phase is formed. The CDD size of the TiNi phase (austenite) reduces from 25 to 4 nm. It is found that the lattice parameters of the TiNi (austenite) and Ni3Ti phases do not change during electrochemical hydrogenation, whereas the crystal lattice parameter of the Ti2Ni phase increases, which indicates the predominant interaction of hydrogen with the Ti2Ni phase. The lattice parameter of the Ti2Ni based phase corresponds to Ti2NiH0.5 and Ti2NiH0.8 hydrides depending on the milling time and hydrogenation time. It is found that there is an “incubation period” of hydrogenation of the Ti2Ni phase, which attains 90 min.