Breakage Test Research Articles

Fractal Analysis of Particle Size and Morphology in Single-Particle Breakage Based on 3D Images

The accurate modeling of single-particle breakage based on three-dimensional (3D) images is crucial for understanding the particle-level mechanics of granular materials. This study aims to propose a systematic framework incorporating single-particle breakage experiments and numerical simulations based on a novel 3D particle reconstruction technique for fractal analysis of particle size and morphology in single-particle breakage. First, the vision foundation model is used to generate accurate particles from 3D images. The numerical approach is validated by simulating the single-particle breakage test with multiple Fujian sand particles. Then, the breakage processes of reconstructed sand particles under axial compression are numerically modeled. The relationship between 3D fractal dimensions and particle size, particle crushing strength, and morphology is meticulously investigated. Furthermore, the implications of these relationships on the particle breakage processes are thoroughly discussed, shedding light on the underlying mechanisms that govern particle breakage. The framework offers an effective way to investigate the breakage behavior of single sand particles, which will enhance understanding of the mechanism of the whole particle breakage process.

Modelling breakage of steelmaking materials for simulation of mechanical degradation during handling

Mechanical degradation of steelmaking materials can have significant economic and environmental implications. Such degradation typically occurs as result of impacts during transportation and handling from their production site to the steelmaking furnace, in operations that include transfers in chutes, ship loading, stockpiling, reclaiming, wagon loading and discharging, etc. Predicting the extent of such degradation and attempting to prevent it, is worthwhile. Fortunately, mechanical degradation during such operations can now be predicted using different approaches, but a proper breakage model is required. The work presents results from single-particle breakage tests of iron ore lump, sinter, briquette, and pellet samples, besides coke, followed by fitting parameters of the Tavares UFRJ Breakage Model. These are then used to simulate degradation in a hypothetical handling circuit. Predictions demonstrate the high susceptibility of iron ore lump and briquette to fines generation, when compared to the other materials, and the occurrence of conditioning for briquettes and sinter, which is the increase in strength of particles surviving handling. Iron ore pellets and coke remained comparatively unaffected by the handling operations simulated, which is explained by their greater resistance to either body or surface breakage.

Accuracy and Precision of the Geopyörä Breakage Test

The Geopyörä breakage test uses two counter-rotating wheels to nip and crush rock specimens with a tightly controlled gap between rollers. This paper presents the detailed measures conducted to evaluate the accuracy and precision of energy measurements across various ore types using the Geopyörä. Force measurement was assessed just for its precision. The outputs were compared directly to the drop weight test (DWT) measures of fragmentation at the same energy and fitted A and b parameters. Test reproducibility was evaluated using a Round-Robin methodology, testing several samples in multiple laboratories. The results confirmed that the new test has sufficient accuracy to match DWT results and excellent precision to assure reproducibility.

New critical state constitutive model considering particle breakage implicitly for uncemented carbonate sands

One of the main problems of carbonate sands is the fragile nature of particles and their susceptibility to breakage. Carbonate sands are affected by volumetric strain even at low stress levels, which is not the case with silicate sands. By defining a simple breakage model, the current study develops an elastoplastic critical state constitutive model that considers the impact of particle breakage on the mechanical behavior of carbonate sands. The particle breakage model depends on mean effective stress and critical breakage stress, which is assumed to correspond with the precompression pressure of soil in the oedometer test. In the proposed model, critical state line movement with the breakage parameter (α) considers the particle breakage effect. Based on the unified clay and sand model (CASM), a novel dynamic yield surface with a shape parameter affected by particle breaking has been created. Certain modifications are made to the modified Cam-Clay stress dilatancy to predict the behavior of carbonate sand. The current model has only ten parameters that simulate the carbonate sands’ behavior even at high-stress levels without any breakage test. Experimental data with different soil densities, loading stress paths, and stress levels were compared with the model, and the results demonstrated satisfactory conformance.

Two cases of cytopenia associated with multiple malformations

The first patient, a 10-year-old girl, presented with pancytopenia and recurrent epistaxis, along with a history of repeated upper respiratory infections, café-au-lait spots, and microcephaly. Genetic testing revealed compound heterozygous mutations in the DNA ligase IV (LIG4) gene, leading to a diagnosis of LIG4 syndrome. The second patient, a 6-year-old girl, was seen for persistent thrombocytopenia lasting over two years and was noted to have short stature, hyperpigmented skin, and hand malformations. She had a positive result from chromosome breakage test. She was diagnosed with Fanconi anemia complementation group A. Despite similar clinical presentations, the two children were diagnosed with different disorders, suggesting that children with hemocytopenia and malformations should not only be evaluated for hematological diseases but also be screened for other potential underlying conditions such as immune system disorders.

Novel homozygous mutation in the FANCA gene (c.2222G>A) in a Chinese girl of Fanconi anemia

AbstractFanconi anemia is the most common inherited bone marrow failure syndrome. Its clinical manifestations include congenital dysplasia, bone marrow hematopoietic failure and tumor susceptibility. At present, there are 23 related gene abnormalities, among which FANCA is the most common. We report a case of a Chinese girl with bone dysplasia and aplastic anemia. The next‐generation sequencing results showed a homozygous mutation in the FANCA gene (c.2222G > A), which was predicted to be a pathogenic mutation based on protein function. This mutation at this site has not been reported in the previous literature. The diagnosis of Fanconi anemia should be determined with combined clinical, chromosome breakage test and gene sequencing results.

Extensive Validation of a New Rock Breakage Test

Comminution is the most power-demanding stage, and the lack of geometallurgical testing, often for financial reasons, may result in an inefficient operation. The Geopyörä rock breakage test was developed with the objective of making mineral variability data more accessible by providing both standard comminution parameters and rock mechanical properties at low cost and with a modest sample size, allowing a larger number of samples to be tested to reduce uncertainties and assure productivity. The objective of this work is to present the results of an extensive validation of this new rock breakage method against two of the main tests currently in use, namely the SMC and Bond ball mill work index tests. More than 100 samples have been tested and the results compared, showing that the new method can accurately estimate the parameters of the traditional tests. This confirms that the new test is a reliable tool for performing comminution and geometallurgical tests.

Diagnosis status and genetic characteristics analysis of Fanconi anemia in China

Objective: To analyze the clinical and molecular diagnostic status of Fanconi anemia (FA) in China. Methods: The General situation, clinical manifestations and chromosome breakage test and genetic test results of 107 pediatric FA cases registered in the Chinese Blood and Marrow Transplantation Registry Group (CBMTRG) and the Chinese Children Blood and Marrow Transplantation Registry Group (CCBMTRG) from August 2009 to January 2022 were analyzed retrospectively. Children with FANCA gene variants were divided into mild and severe groups based on the type of variant, and Wilcoxon-test was used to compare the phenotypic differences between groups. Results: Of the 176 registered FA patients, 69 (39.2%) cases were excluded due to lack of definitive genetic diagnosis results, and the remaining 107 children from 15 hospitals were included in the study, including 70 males and 37 females. The age at transplantation treatment were 6 (4, 9) years. The enrolled children were involved in 10 pathogenic genes, including 89 cases of FANCA gene, 7 cases of FANCG gene, 3 cases of FANCB gene, 2 cases of FANCE gene and 1 case each of FANCC, FANCD1, FANCD2, FANCF, FANCJ, and FANCN gene. Compound heterozygous or homozygous of loss-of-function variants account for 69.2% (72/104). Loss-of-function variants account for 79.2% (141/178) in FANCA gene variants, and 20.8% (37/178) were large exon deletions. Fifty-five children (51.4%) had chromosome breakage test records, with a positive rate of 81.8% (45/55). There were 172 congenital malformations in 80 children.Café-au-Lait spots (16.3%, 28/172), thumb deformities (16.3%,28/172), polydactyly (13.9%, 24/172), and short stature (12.2%, 21/172) were the most common congenital malformations in Chinese children with FA. No significant difference was found in the number of congenital malformations between children with severe (50 cases) and mild FANCA variants (26 cases) (Z=-1.33, P=0.185). Conclusions: FANCA gene is the main pathogenic gene in children with FA, where the detection of its exon deletion should be strengthened clinically. There were no phenotypic differences among children with different types of FANCA variants. Chromosome break test is helpful to determine the pathogenicity of variants, but its accuracy needs to be improved.

A breakage model for DEM based on a probabilistic particle replacement with Voronoi fragments

Due to mechanical stress, bulk material is crushed and fines are produced. This can either be desired in comminution processes or undesired in conveying and storage processes. In this work a novel breakage model for the Discrete Element Method is presented to allow a prediction of the resulting particle size distribution after damaging events. The breakage model is based on a probabilistic particle replacement strategy. Depending on the load, the initial particle is replaced by a breakage pattern tessellated with the Voronoi algorithm. Replacement probabilities and breakage patterns follow results from breakage tests. In contrast to other replacement models, mass and volume remain constant. Initial particles are polyhedral and can be of any shape. Crushing processes with multiple breakage can be simulated. The computational scheme is described in detail. The model was verified and validated with trials of shatter tests and two conveying processes with blast furnace sinter from two different industrial partners.

Cytogenetic findings in Polish patients with suspected Fanconi anemia.

The high sensitivity of cells of Fanconi anemia (FA) patients to DNA cross-linking agents (clastogens), such as mitomycin C (MMC), was used as a screening tool in Polish children with clinical suspicion of FA. The aim of the study was to compare chromosome fragility between 3 groups, namely non-FA, possible mosaic FA and FA patients. The study included 100 children with hematological manifestations and/or congenital defects characteristic of FA, and 100 healthy controls. Blood samples obtained from participants were analyzed using an MMC-induced chromosomal breakage test. Patients with clinical suspicion of FA were divided into 3 subgroups based on the MMC test results, namely FA, possible mosaic FA and non-FA. Thirteen out of 100 patients had a true FA cellular phenotype. The mean value of MMC-induced chromosome breaks/cell for FA patients was higher than for non-FA patients (6.67 ±3.92 compared to 0.23 ±0.18). In addition, the percentage of cells with spontaneous aberrations was more than 9 times higher in FA patients than in non-FA patients. Our results confirmed that the MMC sensitivity test distinguishes between individuals affected by FA, those with possible somatic mosaicism, and patients with bone marrow failure for other reasons, who were classified as non-FA in the first diagnostic step. However, a definitive differential diagnosis requires follow-up mutation testing and chromosome breakage analysis of skin fibroblasts.

Quality Analysis of Welds Made with an Automatic Battery Pack Spot Welding Machine

This paper presents quality testing of battery pack welds for different welding time parameters of an automatic resistance spot welding machine. Several quality testing methods commonly used in studies of welded joints were described. Finally, the breakage test destructive method was chosen and used in this research. To investigate the influence of welder parameters on the quality of the welded joints, the programmable resistance spot welding machine was designed and constructed. As the studied samples, the 18650 cell type and the 8 mm × 0,15 mm cell packaging nickel plated steel tape were chosen as the most commonly used for the construction of battery packs for personal electric vehicles. The impact of each time constants set on the spot welding process was measured by the self-designed and constructed strength testing machine. After a series of tests with different parameters of spot welding process, the final conclusions were formulated.

An Experimental Study on Acoustic Emission of Broken Wires in Steel Strand

Acoustic emission technology, as a nondestructive real-time monitoring technique, has been proven to be an effective method for monitoring dynamic damage of materials. The prestressing strand material used for constructing bridge ties is the focus of this study. This paper reports the experiment setup in detail. This test uses an oil pump to load the prestressing strand at a uniform rate for the tensile breakage test. Real-time signal acquisition of the strand damage during the tensile test was performed using acoustic emission equipment. The preliminary analysis of the data was used to determine the effect of amplifier and transducer type on signal acquisition.

Chromosomal breakage tests in the differential diagnosis of Fanconi anemia and aplastic anemia.

FA patients are hypersensitive to preconditioning of bone marrow transplantation. Assessment of the power of mitomycin C (MMC) test to assign FA patients. We analysed 195 patients with hematological disorders using spontaneous and two types of chromosomal breakage tests (MMC and bleomycin). In case of presumed Ataxia telangiectasia (AT), patients' blood was irradiated in vitro to determine the radiosensitivity of the patients. Seven patients were diagnosed as having FA. The number of spontaneous chromosomal aberrations was significantly higher in FA patients than in aplastic anemia (AA) patients including chromatid breaks, exchanges, total aberrations, aberrant cells. MMC-induced ≥10 break/cell was 83.9 ± 11.4% in FA patients and 1.94 ± 0.41% in AA patients (p < .0001). The difference in bleomycin-induced breaks/cell was also significant: 2.01 ± 0.25 (FA) versus 1.30 ± 0.10 (AA) (p = .019). Seven patients showed increased radiation sensitivity. Both dicentric + ring, and total aberrations were significantly higher at 3 and 6 Gy compared to controls. MMC and Bleomycin tests together proved to be more informative than MMC test alone for the diagnostic classification of AA patients, while in vitro irradiation tests could help detect radiosensitive-as such, individuals with AT.

The effect of energies on the impact breakage characteristic of magnetite ores

The energy applied during breakage is the key to enhancing the magnetite liberation degree and improving quality. The relationship between energy and liberation properties remains unclear due to various complicated factors affecting mineral liberation. Therefore, this work aims to study the effect of energy on the breakage characteristics of magnetite ores; the impact breakage test was conducted on magnetite particle groups at different energies using a drop weight impact tester; the statistical analysis was performed based on the fractal theory to research the particle size distribution; the fracture morphology and liberation properties of these ores were analyzed using scanning electron microscope and mineral liberation analyzer. Results show that the particle size distribution of magnetite after breakage conforms to the fractal law. The larger the energy, the greater the fractal dimension for this distribution, showing a linear relation between them, which implies that the fractal dimension can evaluate the breakage degree. The fracture morphology of magnetite ores indicates that as the energy increases, the intergranular fracture evolves into transgranular fracture, proving the influence of energy on fracture modes. It is found that the magnetite liberation degree first increases and then decreases with the rising of energy, indicating that the magnetite liberation can be improved at an appropriate amount of energy. The above conclusions provide a theoretical reference for optimizing energy and improving broken product quality.

Structural heterogeneity of soil clods: Correlating Weibull parameters to fracture surface topography

Planes of weakness (i.e. cracks) existing in the soil matrix propagate, creating fracture surfaces and fragmenting the clod into smaller clods. The cracking process defines the fracture topography (i.e., roughness) that control many processes from flow exchange between macropore and matrix to local carbon storage and turnover. To date, useful relations between the surface topography of fractures and hydro-mechanical soil properties are missing because of technical and conceptual limitations. The objective was to test the assumption that the Weibull modulus of clod tensile strength can be related to the surface topography of fractures that resulted from the breakage of standardized soil clods. For carrying out standardized indirect tensile strength tests, a tension testing machine was constructed to prompt and monitor aggregate rupture. A total of 280 clods of 4 size-classes from two contrasting soils were considered. Clods were from the finer-textured Bt horizon of a Haplic Luvisol and the coarser-textured C horizon with lower amount of organic compounds of a Haplic Regosol. The natural clods were standardized in a cylindrical shape, in order to capture differences in the structural heterogeneity in terms of particle binding forces and porosity quantified by the Weibull modulus (m) of tensile strength. The stronger hierarchical organisation of the structure was quantified by smaller values of m (Bt: 3.1 vs C: 3.6) and the mass fractal dimension (Bt: 2.93 vs C: 2.98), and by higher values of the friability (m−1) (Bt: 0.14 vs C: 0.06). From these results, the random forest ensemble learning algorithm showed that the spatial heterogeneity of the organo-mineral pore coating (O-M) (shape factor of frequency distribution Bt: 0.58 vs C: 0.69), and not the organic carbon content (OC) (Bt: 0.48 vs C: 0.1 %), was the most important variable for predicting tensile strength (importance O-M: 0.21 vs OC: 0.09). Furthermore, the greater the spatial heterogeneity of the clod (m values ca. 1.4 for Bt) the lower the fracture surface roughness (ca. 1.8 µm2 µm−2) when compared to a more homogeneous clod (m values ca. 3.6, fracture surface roughness ca. 2.7 µm2 µm−2 for C). According to the random forest ensemble learning algorithm, porosity was the most important variable (variable importance 0.95) for predicting the rupture surface roughness followed by the spatial heterogeneity of the organo-mineral pore coatings, water content, and soil texture. Fracture surface roughness decreased when increasing porosity or decreasing the shape factor of the frequency distribution of organo-mineral coatings. Results confirmed that the Weibull modulus of clod tensile strength can be related with clod fracture surface roughness resulting from standardized clod breakage tests. This sheds light on the Weibull modulus as a distinct macro property for linking soil hydraulic and mechanical properties. This is of special importance in the parameterization of coupled models that combine the spatial heterogeneity of soil physical properties with the effects of hydrostatic forces on the soil structure.

Next-generation sequencing reveals novel variants and large deletion in FANCA gene in Polish family with Fanconi anemia

BackgroundFanconi anemia (FA) is the most common inherited bone marrow failure syndrome. However, establishing its molecular diagnosis remains challenging. Chromosomal breakage analysis is the gold standard diagnostic test for this disease. Nevertheless, molecular analysis is always required for the identification of pathogenic alterations in the FA genes.ResultsWe report here on a family with FA diagnosis in two siblings. Mitomycin C (MMC) test revealed high level of chromosome breaks and radial figures. In both children, array—Comparative Genomic Hybridization (aCGH) showed maternally inherited 16q24.3 deletion, including FANCA gene, and next generation sequencing (NGS) disclosed paternally inherited novel variants in the FANCA gene—Asn1113Tyr and Ser890Asn. A third sibling was shown to be a carrier of FANCA deletion only.ConclusionsAlthough genetic testing in FA patients often requires a multi-method approach including chromosome breakage test, aCGH, and NGS, every effort should be made to make it available for whole FA families. This is not only to confirm the clinical diagnosis of FA in affected individuals, but also to enable identification of carriers of FA gene(s) alterations, as it has implications for diagnostic and genetic counselling process.

P814: CLINICAL CHARACTERISTICS AND GENE MUTATION ANALYSIS OF 148 CHILDREN WITH FANCONI ANEMIA IN CHINA

Background: Fanconi anemia (FA) is a rare autosomal recessive, X-linked (FANCB) or autosomal dominant (FANCR/RAD51) disease of bone marrow failure. Pathogenesis is mainly caused by gene mutation related to the FA pathway. At present, at least 23 genes have been discovered to play a role in the FA pathway. The gene mutations of FA have been reported in more and more countries. In China, there no large-scale cases have been reported. Aims: In this study, we analyzed the clinical characteristics of 148 FA children from 20 provinces in China from October 2003 to October 2021. We explored the relationship between genotype and phenotype in 105 children with FA genotyping results. This is the largest series of subtyped Chinese Fanconi anemia patients to date, and the results will be helpful for future clinical management. Methods: A total of 148 Fanconi anemia patients from 140 families were diagnosed by clinical phenotype, family history, chromosome breakage test induced by mitomycin C, Single cell gel electrophoresis experiment, targeted - sequence, whole exon sequencing, and MLPA method from October 2003 to October 2021. Since there were no genetic test results for the children before 2010, only the 105 patients after 2010 had gene sequencing results, which allowed genotyping. DNA damage repair defects were detected by MMC-induced Single cell gel electrophoresis and chromosome breakage experiments. Targeted-seq was used to identify the FA mutations of the patients. Multiplex ligation-dependent probe amplification (MLPA) was performed to detect large fragment deletions in patients with negative results in the targeted-seq but conforming to the FA by MMC-induced chromosome breakage experiments test and clinical manifestations. We performed WES of DNA samples from five patients and their parents. Results: 1) The most common subtype of FA in China is FA-A, followed by FA-D2 and FA-P。2) The most common deformities in FA-A patients are finger deformities and skin pigmentation, while heart deformities are more common in FA-D2/B/G/I/P subtypes. 3) The common mutations of FANCA are exon23c.2101A>G, exon28c.2778 + 1G>A, exon34c.3348 + 1G>A, exon21c.1844delC, and exon30 C2941T>G, which are different from Korea and Japan. 4) Homozygous nonsense mutation of exon32 c.3188G>A and exon29 c.2851C>T in FA-A likely benign, but the homozygous splicing mutation in exon29c.2852 + 1G>T is harmful. 4) Children with splicing and Del mutations of FANCD1 gene had poor clinical prognosis, while children with homozygous mutations of exon10c. 1792A>G is likely benign. 5) Cases of initial diagnosis of MDS or poor disease progression tend to occur in FA-B/C/E/G/J/L/M and FA-S subtypes. 6)Chromosome 1, 3, 7, and 8 abnormalities and mutations of SF3B1 P53 are related to disease progression. Summary/Conclusion: We made a comprehensive description and analysis of the clinical characteristics and mutant genes of Children with FA in China. We proposed the mutation sites related to clinical prognosis and the cytogenetic abnormalities of disease progression, providing new data for our comprehensive understanding of FA. Our data will be useful for FA future menagement.

Mechanical and Hydraulic Properties of Recycled Concrete Aggregates Mixed with Clay Brick Aggregates and Particle Breakage Characteristics for Unbound Road Base and Subbase Materials in Vietnam

The construction industry is one of the key industries with high potential for the circular economy; the promotion of reuse and recycling of construction and demolition waste (CDW) is essential for sustainable urban development. In this study, a series of compaction, California bearing ratio, saturated hydraulic conductivity, and particle breakage tests of well– and poor–graded mixtures of recycled clay brick aggregates (RCBs) and recycled concrete aggregates (RCAs) with maximum aggregate diameters of 19, 25, and 37.5 mm were carried out to examine the practical application of those mixtures to unbound roadbed materials in Vietnam. The experimental results suggest that the maximum amount of RCBs added to RCAs should be less than 30% when applied to unbound roadbed materials. In addition, it was found that the mixing proportions of RCBs and RCAs and the maximum aggregate diameter, gradation of aggregates, and initial moisture condition control the saturated hydraulic conductivity. Further, the particle breakage characteristics under compaction were carefully examined, and it was found that the percentage increment/decrement, as well as a newly introduced method of estimating the mixing proportions of RCAs and RCBs in the fine fraction (&lt;2.36 mm), is effective in understanding the mechanism of particle breakage of RCA and RCB mixtures.

Single and multiple breakage events in fine particle breakage testing with a rigidly-mounted roll mill

For the prediction of breakage in fine grinding processes (<200 μm), simulation based on population balance models and/or discrete element method is often applied. Both numerical techniques require a deep understanding of the breakage mechanisms within the grinding process. Depending on the breakage mechanism, different devices are available to characterize the breakage behaviour of the feed material, such as the breakage function or breakage rate. For characterizing breakage specific parameters of particles in fine grinding, a new breakage tester based on a rigidly-mounted roll mill was presented in a previous study. The present work focuses on the investigation of progressive stress events in fine particle breakage testing. For this, the effect of weakening and breakage history is analysed. As a result, the shape of the resulting particle size distribution and the particle strength are influenced by previous stressing. Therefore, a new approach considering the history of particle breakage is introduced.

Effects of the Particle Shape and Size on the Single‐Particle Breakage Strength

The strength and deformation of a soil foundation are related to the strength of each particle. Maybe the shape affects the strength of a particle. In this study, single‐particle breakage tests were conducted on limestone particles of different sizes to analyze the influence of limestone particle shapes on the particle crushing strength. The results showed that 90 percent of limestone particle shapes were oblate spherical, subspherical, and long spherical particles randomly selected from the soil foundation. The single‐particle breakage test results showed that the characteristic stress of limestone particles increases with the increased particle size. The crushing strength of limestone particles increased with the increase in particle size. There was a significant size effect on the single‐particle compressive strength. The relationship between the characteristic strength and the particle size can be fitted by a power exponential formulation of four types of limestone particle shapes. The more irregular the particle shape, the smaller the Weibull modulus (m) and the power index and the more obvious the particle strength size effect.