Primary Iron Research Articles

Gallium(III)-Salophen as a Dual Inhibitor of Pseudomonas aeruginosa Heme Sensing and Iron Acquisition.

Pseudomonas aeruginosa is an opportunistic bacterium that causes life-threatening infections in immunocompromised patients. In infection, it uses heme as a primary iron source and senses the availability of exogenous heme through the heme assimilation system (Has), an extra cytoplasmic function σ-factor system. A secreted hemophore HasAp scavenges heme and, upon interaction with the outer-membrane receptor HasR, activates a signaling cascade, which in turn creates a positive feedback loop critical for sensing and adaptation within the host. The ability to sense and respond to heme as an iron source contributes to virulence. Consequently, the inhibition of this system will lead to a disruption in iron homeostasis, decreasing virulence. We have identified a salophen scaffold that successfully inhibits the activation of the Has signaling system while simultaneously targeting iron uptake via xenosiderophore receptors. We propose this dual mechanism wherein free Ga3+-salophen reduces growth through uptake and iron mimicry. A dual mechanism targeting extracellular heme signaling and uptake together with Ga3+-induced toxicity following active Ga3+salophen uptake provides a significant therapeutic advantage while reducing the propensity to develop resistance.

Electrolytic Iron Production from Alkaline Bauxite Residue Slurries at Low Temperatures

Primary iron metallurgy is characterised by significant direct carbon dioxide emissions, due to the carbothermic reduction of the iron ore. This paper deals with the electrification of primary iron production by developing a new and innovative process for the carbon-free production of metallic iron from bauxite residue which is a byproduct of the alumina industry. It is based on the electroreduction of iron oxides from bauxite residue suspensions in concentrated sodium hydroxide solutions, at low temperature and normal pressure. The iron oxide source used in the present study is bauxite residue provided by MYTILINEOS SA, Metallurgy Business Unit-Aluminium of Greece. The research study is a preliminary screening of bauxite residue as a potential raw material for iron production by performing experiments in a small-scale electrolysis cell. The first results presented here show that iron can be produced by the reduction of iron oxides in bauxite residue with high Faradaic efficiency (>70%). Although significant optimisation is needed, the novel process shows great promise.

P0603INFLUENCE OF FERRITIN VALUES IN THE PORGNOSIS OF ACUTE KIDNEY INJURY

Abstract Background and Aims Acute Kidney Injury (AKI) is one of the most frequent causes of hospitalization and many factors have been associated to its prognosis and recovery. The role of iron in AKI physiopathology and its influence is not well known. Recent studies have shown that elevated levels of catalytic iron are associated with higher mortality in patients with AKI, however, catalytic iron is not available in usual clinical practice. Ferritin, especially abundant in the liver, is the primary intracellular iron storage protein. A small amount is secreted to the circulation and is an indirect marker of total body iron deposits. In this study we analyze the influence of iron, with ferritin values, in the prognosis of AKI. Method We developed a retrospective, single-center study that enrolled patients with AKI, hospitalized in our center between 2013 and 2014 with iron metabolism values in the first 72 hours after admission. At baseline, we collected demographic information, comorbidities, reason for admission and iron metabolism values (ferritin, transferrin, transferrin saturation index and serum iron). We analyzed variables associated with low and high ferritin values and its impact in AKI long-term prognosis using univariate and multivariable Cox regression. Results Of the 1731 analyzed patients, 833 (48.1%) had ferritin records. The mean age was 78±14 years and 48% of the patients were women. The most frequent comorbidity was hypertension (76%), followed by chronic kidney disease (46%), dyslipidemia (44%), heart failure (31%), diabetes mellitus (29%) and atrial fibrillation (27%). The most frequent reason for admission was infection (35%) followed by AKI (19%). Ferritin values differed significantly according age (p<0.0001), sex (p=0.024), diabetes (0.012), hypertension (p=0.002), neoplasia (p=0.016), reason for admission (p=0.018), baseline CKD-EPI (0.012) and lactate at admission (p<0.0001). During the hospitalization, 165 (20%) patients died. Factor associated to mortality were ferritin>500 ng/ml (p=0.013), lactate at admission (p<0.001), age (p=0.045), hypertension (p=0.014), dyslipidemia (p<0.001), ischemic heart disease (p=0.006), chronic kidney disease (p=0.001), baseline CKD-EPI (p=0.01), atrial fibrillation (p=0.005), neoplasia (p=0.023), Barthel index (p<0.001) and hemoglobin (p=0.006) and bicarbonate (p=0.012) at admission. Multivariate logistic regression demonstrated that ferritin levels over 500 ng/mL was an independent predictor of mortality (1.6 [1,1-2,3] HR [CI 95%]) (p=0.013). Conclusion Ferritin values higher than 500 ng/mL independently predicts mortality in patients admitted with AKI.

Novel mutations in the bone morphogenetic protein 6 gene in patients with iron overload and non-homozygous genotype for the HFE p.Cys282Tyr mutation

BackgroundFive main genes are associated with hemochromatosis; however, current studies show that, in addition to these genes, others may be associated with primary iron overload (IO). One of these is the bone morphogenetic protein 6 (BMP6), which encodes a protein that modulates hepcidin synthesis and, consequently, iron homeostasis. AimTo identify BMP6 gene pathogenic variants in patients with IO and non-homozygous genotype for the HFE p.Cys282Tyr mutation. Materials and methodsFifty-three patients with primary IO and non-homozygous genotype for the HFE p.Cys282Tyr were selected. Subsequent bidirectional DNA sequencing of BMP6 exons was performed. ResultsTwo novel variants were found. One at homozygous state p.Gln158Ter (c.472C>T) was pathogenic, the other one at heterozygous state p.Val394Met (c.1180G>A) was of uncertain significance (VUS); the third variant at heterozygous state p.Arg257His (c.770G>A) has already been described and associated with IO. No BMP6 pathogenic variants that would explain iron overload phenotypes were detected in 94% of the studied patients. ConclusionIdentification of the BMP6 pathogenic variants in Brazilian patients with primary IO might contribute to the genetic understanding of this phenotype.

From Environment to Genome and Back: A Lesson from HFE Mutations.

The environment and the human genome are closely entangled and many genetic variations that occur in human populations are the result of adaptive selection to ancestral environmental (mainly dietary) conditions. However, the selected mutations may become maladaptive when environmental conditions change, thus becoming candidates for diseases. Hereditary hemochromatosis (HH) is a potentially lethal disease leading to iron accumulation mostly due to mutations in the HFE gene. Indeed, homozygosity for the C282Y HFE mutation is associated with the primary iron overload phenotype. However, both penetrance of the C282Y variant and the clinical manifestation of the disease are extremely variable, suggesting that other genetic, epigenetic and environmental factors play a role in the development of HH, as well as, and in its progression to end-stage liver diseases. Alcohol consumption and dietary habits may impact on the phenotypic expression of HFE-related hemochromatosis. Indeed, dietary components and bioactive molecules can affect iron status both directly by modulating its absorption during digestion and indirectly by the epigenetic modification of genes involved in its uptake, storage and recycling. Thus, the premise of this review is to discuss how environmental pressures led to the selection of HFE mutations and whether nutritional and lifestyle interventions may exert beneficial effects on HH outcomes and comorbidities.

Study on Direct Reduction Process of Cylindrical Briquetting Hematite

There are two types of iron resources such as primary iron ore and iron sand. In general, primary iron ores use as raw materials in iron and steel making and can reduce directly. In Direct reduction process, Fe2O3 (hematite) is converted to metallic iron by the removal of oxygen. This work presents a heat transfer rate study for direct reduction process of iron ore cylindrical briquette. An investigation has been carried out of different reduction parameter such as different sizes cylindrical geometry over temperatures ranging from 700°C to 1100°C for reaction time from 10 minutes to 1 hour. The result was indicated that the value of the heat transfer rate decreases in the core and outer parts of the cylinder briquettes.

The High Temperature Co-Processing of Nickel Sulfide and Nickel Laterite Sources

The pressure oxidation of low-grade nickel sulfide concentrate with high iron sulfides content generates significant amounts of sulfuric acid that must be neutralized. This acid can be utilized to leach metal values from ores such as nickel laterites. The present study demonstrates the use of a low-grade nickel concentrate generated from Poseidon Nickel Mt Windarra ore to enable additional nickel and cobalt extraction from a Bulong Nickel Operation nickel laterite blend. The co-processing of these materials at 250 °C, with oxygen overpressure, using total pulp densities of 30% or 40% w/w, and a range of nickel concentrate to nickel laterite mass ratios between 0.30–0.53, yielded base metal extractions of 95% or greater. The final free acid range was between 21.5–58.5 g/L, which indicates that enough in situ sulfuric acid was generated during co-processing. The acid was shown from mineralogical analysis to be efficiently utilized to dissolve the laterite ore, which indicates that the primary iron hydrolysis product was hematite, while the aluminum-rich sodium alunite/jarosite phase that formed hosts approximately 5% of the hydrolyzed iron.

Investigating the longitudinal development of EAS with ultra high energies

The simulation of the extensive air showers was performed by investigating the longitudinal development parameters (N and Xmax) by using AIRES system version 19.04.0. The simulation was performed at the energy range (1018-1020 eV) for different primary particles (such as primary proton and iron nuclei) and different zenith angles. The longitudinal development curves of EAS are fitted using Gaussian function that gave a new parameters for different primary particles and different zenith angles at the energy range (1018-1020 eV). The comparison between the obtained results, the parameterized longitudinal development using Gaussian function that gave a new parameters for different primary particles with the experimental measurements (AUGER experiment) that gave a good agreement for primary proton and iron nuclei at the energy 1019 eV for θ = 0˚.

Diagnosis and management of hereditary haemochromatosis.

Hereditary haemochromatosis, one of the most common genetic disorders in the United States, can produce systemic iron deposition leading to end-organ failure and death if untreated. The diagnosis of this condition can be challenging as elevated serum ferritin may be seen in a variety of conditions, including acute and chronic liver disease, a range of systemic inflammatory states, and both primary and secondary iron overload syndromes. Appropriate and timely diagnosis of haemochromatosis is paramount as simple interventions, such as phlebotomy, can prevent or reverse organ damage from iron overload. The recognition of other aetiologies of elevated ferritin is also vital to ensure that appropriate intervention is provided and phlebotomy only utilized in patients who require it. In this review, we summarize the existing data on the work up and management of hereditary haemochromatosis and present a practical algorithm for the diagnosis and management of this disease.

Altered primary iron sulfides in CM2 and CR2 carbonaceous chondrites: Insights into parent body processes

AbstractThe presence of primary iron sulfides that appear to be aqueously altered in CM and CR carbonaceous chondrites provides the potential to study the effects and, by extension, the conditions of aqueous alteration. In this work, we have used SEM, TEM, and EPMA techniques to characterize primary sulfides that show evidence of secondary alteration. The alteration styles consist of primary pyrrhotite altering to secondary pentlandite (CMs only), magnetite (CMs and CRs), and phyllosilicates (CMs only) in grains that initially formed by crystallization from immiscible sulfide melts in chondrules (pyrrhotite‐pentlandite intergrowth [PPI] grains). Textural, microstructural, and compositional data from altered sulfides in a suite of CM and CR chondrites have been used to constrain the conditions of alteration of these grains and determine their alteration mechanisms. This work shows that the PPI grains exhibit two styles of alteration—one to form porous pyrrhotite‐pentlandite (3P) grains by dissolution of precursor PPI grain pyrrhotite and subsequent secondary pentlandite precipitation (CMs only), and the other to form the altered PPI grains by pseudomorphic replacement of primary pyrrhotite by magnetite (CMs and CRs) or phyllosilicates (CMs only). The range of alteration textures and products is the result of differences in conditions of alteration due to the role of microchemical environments and/or brecciation. Our observations show that primary sulfides are sensitive indicators of aqueous alteration processes in CM and CR chondrites.

Comparative Study of Permanent Magnet Assisted Linear Switched Reluctance Motor and Linear Flux Switching Permanent Magnet Motor for Railway Transportation

Linear switched reluctance motor (LSRM) has been investigated and supposed as a good candidate in railway system. Recently, permanent magnet assisted switched reluctance motor (PMA-SRM) has attracted extensive attention because of the high torque, robust structure and low cost. However, all these researches focus on the application of small air gaps. How does PMA-SRM perform in large air gap? No research has been conducted until now. As we know, there are many similarities between linear flux switching permanent magnet (LFSPM) motor and permanent magnet assisted linear switched reluctance motor (PMA-LSRM) such as similar primary iron, winding structure, robust secondary and a small amount of permanent magnets. In this case, what are the similarities and differences between these two kinds of motors in terms of electromagnetic characteristics? This paper will compare these two kinds of motors based on the volume of rail transit from the following aspects: thrust force, thrust ripple, efficiency. First, the topology, operation principle of the two LSRMs are introduced and designed. Then, the electromagnetic performance of LSRM is optimized through two dimensional finite element analysis (FEA) based on ANSYS software. The optimization objectives of PMA-LSRM are to maximize the thrust and to minimize the ripple at the given dimensions and the rated condition. The comparison of electromagnetic characteristics between LFSPM motor and PMA-LSRM is completed. Finally, it is concluded that the permanent magnets are not conducive to improving the power of LSRM. And the PMA-LSRM is not outstanding compared with LFSPM motor under the condition of large air gap for rail transit.

Is Pakistan Really a Pollution Haven Country?

In this study, the Pollution Haven Hypothesis (PHH) validity has been tested for Pakistan and also investigates its impact on exports of Pakistan. The PHH predicts that environmental regulations variability among countries or regions affect polluting industries location and trade flows. This study used the Kolstad (2011) model and Trade Balance Index (TBI) of Lafay (1992) to test the FDI-environment and trade-environment relationship for existence of the pollution haven effect. Time series data from 1980-2017, Autoregressive Distributed Lag (ARDL) or bound test of cointegration is used to investigate the short and long-run relationships. We found positive and statistically significant short-run and long-run relationships between CO2 (proxy for lax environmental policy) and FDI inflows. Finally, Trade Balance Index (TBI) of metal and mining, primary iron & steel, chemicals and rubber products does not support the PHH. While the pulp & paper and the textile industry validated the existence of pollution haven effect. We can conclude that PHH does exist for Pakistan and therefore effective policies needs to be put in place to encourage the FDI inflows without having implications for the environment and thus quality of life of the citizens.

Curculigoside Protects against Excess-Iron-Induced Bone Loss by Attenuating Akt-FoxO1-Dependent Oxidative Damage to Mice and Osteoblastic MC3T3-E1 Cells.

Summary The present investigation found that curculigoside (CUR) can prevent excess-iron-induced bone loss in mice and cells through antioxidation and inhibiting excess-iron-induced phosphorylation of the Akt-FoxO1 pathway. CUR can attenuate the decreasing of cell viability, enhance autophagy, potentiate the antioxidant effect, and reduce apoptosis in MC3T3-E1 cells treated with excess iron through regulating the expression of FoxO1 target gene. Introduction Oxidative stress induced by iron overload is an important factor involved in primary osteoporosis disease and iron overload-related diseases. Curculigoside (CUR), a phenolic glycoside found abundantly in Curculigo orchioides Gaertn., has been demonstrated to possess antioxidant and antiosteoporotic properties. The aim of the present study is to explore the underlying molecular mechanism of CUR on excess-iron-induced bone loss in mice and osteoblastic MC3T3-E1 cells. Methods An iron-overload mice model was used to study the protective effects of CUR on bone loss induced by oxidative stress. Serum bone metabolism markers and antioxidant enzymes were also measured. To explore the antioxidant mechanism of CUR, the MC3T3-E1 osteoblastic cell line was used. Results In vivo studies showed that BMD and microarchitectural parameters were improved after a 3-month administration of CUR. CUR improved the biochemical parameters related to bone metabolism and the expressions of Runx2, OCN, and type 1 collagen and increased the formation of bone-mineralized nodules in vitro. CUR also inhibited ROS generation and increased the activities of antioxidant enzymes both in vivo and in vitro treated with excess iron. CUR can upregulate the level of FoxO1 and Nrf2, downregulate the level of p53 and the phosphorylation level of FoxO1, improve nuclear translocation of FoxO1, probably by inhibiting the IGFR/AKT signaling pathway, then increased cell viability and autophagy, and reduced apoptosis of MC3T3-E1 cells treated with excess iron by regulating the expression of FoxO1 target genes MnSOD, Gadd45a, Bim, FasL, and Rab7. Conclusions These results demonstrated that CUR was able to alleviate bone loss induced by oxidative stress resulting from iron overload, suggesting its potential use for the treatment of primary osteoporosis and bone loss in iron-overload-related diseases.

Synthetic Humic Acids Solubilize Otherwise Insoluble Phosphates to Improve Soil Fertility.

Artificial humic acids (A‐HA) made from biomass in a hydrothermal process turn otherwise highly insoluble phosphates (e.g. iron phosphate as a model) into highly available phosphorus, which contributes to the fertility of soils and the coupled plant growth. A detailed electron microscopy study revealed etching of the primary iron phosphate crystals by the ‐COOH and phenolic groups of humic acids, but also illustrated the importance of the redox properties of humic matter on the nanoscale. The combined effects result in the formation of then bioavailable phosphate nanoparticles stabilized by humic matter. Typical agricultural chemical tests indicate that the content of total P and directly plant‐available P improved largely. Comparative pot planting experiments before and after treatment of phosphates with A‐HA demonstrate significantly enhanced plant growth, as quantified in higher aboveground and belowground plant biomass.

Synthetic Humic Acids Solubilize Otherwise Insoluble Phosphates to Improve Soil Fertility

AbstractArtificial humic acids (A‐HA) made from biomass in a hydrothermal process turn otherwise highly insoluble phosphates (e.g. iron phosphate as a model) into highly available phosphorus, which contributes to the fertility of soils and the coupled plant growth. A detailed electron microscopy study revealed etching of the primary iron phosphate crystals by the ‐COOH and phenolic groups of humic acids, but also illustrated the importance of the redox properties of humic matter on the nanoscale. The combined effects result in the formation of then bioavailable phosphate nanoparticles stabilized by humic matter. Typical agricultural chemical tests indicate that the content of total P and directly plant‐available P improved largely. Comparative pot planting experiments before and after treatment of phosphates with A‐HA demonstrate significantly enhanced plant growth, as quantified in higher aboveground and belowground plant biomass.

Regulation of Iron Homeostasis By PTG-300 Improves Disease Parameters in Mouse Models for Beta-Thalassemia and Hereditary Hemochromatosis

Hepcidin-Ferroportin axis dictates optimal absorption of dietary iron as well as systemic iron levels. This is crucial for providing sufficient iron needed for cellular functions while also preventing iron toxicity. PTG-300 (currently in a Phase 2 clinical study for beta-thalassemia) is a peptide mimetic of natural hepcidin that targets the major iron transporter, ferroportin, and causes its internalization & subsequent degradation. The pharmacodynamic effects of PTG-300 are the reductions in serum iron and transferrin-saturation (TSAT) due to reduced ferroportin expression on cells that store or recycle iron. We chose to demonstrate in two mouse models with iron dysregulation, that our hepcidin mimetics improve disease parameters by correcting dysregulated iron homeostasis. Beta-thalassemia is characterized by an imbalance in alpha-beta globin ratio in erythrocytes due to underlying beta-globin gene mutations. The excess alpha-globin, along with associated heme and iron, form "hemichrome" aggregates that integrate into the membranes of RBCs. The labile iron in these hemichromes generate ROS and are toxic to the cells, causing premature hemolysis of circulating RBCs and reduction in their lifespan. In a mouse model for beta-thalassemia, Hbbth3/+, we investigated the efficacy of a hepcidin mimetic in reducing hemichrome aggregation by limiting iron in the erythroid progenitors, and thereby reducing iron toxicity in RBCs. Subcutaneous injections of 1 mg/kg PN-8772 (analog of PTG-300 which has similar in vitro and in vivo potency) were administered every other day (Q2D) for a period of 4 weeks. At the end of the study, hemichrome aggregates were extracted from RBC membranes, and then analyzed on a TAU gel to quantify the cytoskeleton α-globin band intensities (Casu et al, Blood 2016). Hemichrome aggregates were reduced in groups treated with PN-8772 as compared to untreated controls, with concurrent improvements in hemoglobin and reductions in reticulocytes. Treatment with oral chelator Deferasirox (200 mg/kg; daily) did not show reduction in hemichrome aggregation, while it significantly lowered liver iron-overload. RBCs in Hbbth3/+ mice express aberrant morphologies due to the underlying hemichrome toxicity, similar to the phenotypes expressed in human beta-thalassemia. Chronic treatment with PN-8772 (as described above) also resulted in a significant reduction in aberrant morphologies that are indicative of hemolysis, viz. spherocytes & schistocytes. In a separate study, flow cytometry was used to monitor the survival of RBCs in Hbbth3/+ mice. At the end of 4 weeks of PTG-300 treatment (1 mg/kg, Q2D) the RBCs were marked by an in-life biotinylation method (Schmidt et al, Blood 2013) and subsequently followed over 49 days with continued treatment. There was a significant increase in survival of RBCs as compared to untreated controls. In summary, we demonstrate that by limiting iron in the developing erythroblasts and iron toxicity in RBCs, PTG-300 therapy has the potential to improve the quality of the RBCs and their oxygen carrying capacity, thereby ameliorating anemia. In beta-thalassemia, the clinical presentation includes secondary iron overload in various organs because of hyperabsorption of dietary iron, exacerbated by frequent blood transfusions that are required for management of anemia. Similarly, in hereditary hemochromatosis (HH) there is hyperabsorption of dietary iron leading to primary iron overload. We used a hemochromatosis mouse model (HFE) to demonstrate the effectiveness of PTG-300 therapy in limiting systemic iron toxicity by regulating TSAT and in preventing hyper-iron absorption. The model is characterized by homozygous deletion of HFE with severely low hepcidin levels and consequently very high TSAT (~100%). In this model, a single dose of PTG-300 at 2.5mg/kg reduced TSAT by ~60% at 10-hour post-dose, as compared to untreated controls. Sustained TSAT reduction by chronic treatment will therefore mitigate toxic effects of labile iron. Two weeks of chronic treatment with PTG-300 (2.5 mg/kg, Q2D) effectively prevented iron deposition in the liver. Overall our data suggests that PTG-300 has the potential to be an effective treatment in hemoglobinopathies, like beta-thalassemia, and Hereditary Hemochromatosis, by reducing systemic labile iron toxicity by limiting TSAT, preventing organ iron deposition & improving anemia (in case of thalassemia). Disclosures Taranath: Protagonist Therapeutics: Employment. Bourne:Protagonist Therapeutics: Employment. Zhao:Protagonist Therapeutics: Employment. Frederick:Protagonist Therapeutics: Employment. King:Protagonist Therapeutics: Employment. Liu:Protagonist Therapeutics: Employment.

Cascade Particles in Extensive Air Showers with Energy Above 1017 eV According to Longstanding Measurements at the Yakutsk Array

Lateral distribution of cascade particles was studied in extensive air showers initiated by cosmic rays with energy above 1017 eV. The study is based on the data collected with ground-based scintillation detectors of the Yakutsk array during the continuous observational period from 1977 to 2017. Particle density measured in experiment is compared to the results of simulations performed for primary protons and iron nuclei within the framework of four ultra-high energy hadronic interaction models. Particle density obtained in the simulation was converted to signal of the scintillation detectors of the array. From the parameters of the resulted lateral distribution function, features of extensive air showers longitudinal development were derived.

Muons in Extensive Air Showers with Energy above 1017 eV According to the Long Standing Studies at the Yakutsk Array

lateral distribution of muons was studied in extensive air showers initiated by cosmic rays with energy above 1017 eV. The study is based on the experimental data of underground scintillation detectors with 1-GeV energy threshold collected during the continuous observational period lasting from 1986 to 2017. Experimentally measured values of muon density are compared to results of simulations performed for primary protons and iron nuclei within the framework of four ultra-high energy hadronic interaction models. The density of particles with 1-GeV threshold obtained in simulations was then converted to the signal of ground-shielded scintillation detectors of the array. Studying the features of the resulting muon lateral distribution has allowed us to reconstruct parameters of longitudinal development of extensive air showers.

Novel Decoupling Modular Permanent Magnet Flux-Switching Linear Motor

In this paper, a novel decoupling modular permanent magnet flux-switching linear motor (PMFSLM) is proposed. The primary iron core of the motor is a nonsegmented structure without magnetic coupling among different modules. In contrast to a normal PMFSLM driven by a sinusoidal current, the proposed PMFSLM adopts square-wave current driving. On the basis of structure and working characteristics, a piecewise linear permeance model of a single-module PMFSLM is presented, and a specific design method of the novel modular three-phase PMFSLM is proposed. The proposed design method aims at reducing the cogging force and force ripple of a three-phase PMFSLM. Through further electromagnetic analysis, a set of structural parameters is proposed, based on which finite-element analysis (FEA) is conducted. FEA results show that the design aim is realized even with the influence of armature winding commutation. Prototype experiments of a single-module PMFSLM are performed, and experimental results agree well with FEA results. The findings of this paper verify the effectiveness and practicability of the novel modular PMFSLM and the proposed design method.

Thermodynamic Functions of Fe3B Borides

In this work we study the structural properties of hypoeutectic and hypereutectic Fe-B alloys, depending on the temperature of heating above the liquidus line and the cooling rate. Experiments were carried out for the Fe-B system alloys with boron content of 2.0 - 4.5 % (wt.), the rest is iron. To determine physical properties of the alloys microstructural and X-ray diffraction analysis were used. It is shown that overheating of the molten alloy to 150 K above the liquidus line and aftercooling leads to complete suppression of the formation of primary iron crystals in the hypoeutectic alloys and partially to suppression of Fe2B formation in the hypereutectic alloys of the Fe-B system. For the first time it is shown that heating of Fe-B hypoeutectic alloys to 150 K above the liquidus line and cooling with a rate of 103 K/s lead to formation of Fe3B boride in as-cast state, which was present in the eutectic colony.