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Summary Objectives Iron amino acid chelates have been developed to be used as food fortificants and therapeutic agents in the treatment of iron deficiency anemia. Purpose To compare the efficacy of Oral iron bisglycinate chelate (FeBC), lactoferrin (LF), lactoferrin with iron and iron polymaltose complex (IPC) in treatment of iron deficiency anemia (IDA). Methods: a comparative study was conducted on 120 children with IDA, they attended to outpatient clinic at Menoufia University Hospitals within a period from April to November 2019. All subjects were classified into FeBC Group (30 children received iron bisglycinate), LF Group (30 children received lactoferrin 100 mg), LF with iron Group (30 children received 30% iron saturated lactoferrin) and IPC Group (30 children received iron polymaltose complex with elemental iron of6 mg/kg/day). Serum iron, serum ferritin, transferrin saturation was investigated. Results After treatment serum iron, serum ferritin and transferrin saturation improved in FeBC group than LF group, in LF with iron group than LF group, and in IPC group than LF group. Serum ferritin improved in LF with iron group than IPC group. Side effects of drugs were higher in FeBC group than LF group, and higher in LF with iron group than FeBC group. Conclusions Adding lactoferrin to iron helps increasing iron stores more than using iron alone in treatment of iron deficiency anemia. Lactoferrin is less effective than lactoferrin with iron, iron bisglycinate chelate and iron polymaltose complex in treatment of iron deficiency anemia.

It is shown that the earlier discovered features of the composition and properties of electrochemical coatings obtained by the induced codeposition from alloys of iron group metals (W, Mo, Re) such as nanocrystallinity (X-ray amorphism), macroscopic dimensional effects of microhardness and corrosion resistance, the effect of the volume current density on the properties and composition are a consequence of the fractality of the solutions of complexes (citrate, gluconate, etc.) in combination with the intensive interfacial exchange. In this case, the kinetics of nano-nucleation limits the size of the resulting alloy nucleus, as a result of which water molecules participate in the formation of coatings, leading to the incorporation of oxide-hydroxide inclusions into the solid phase and hydrogenation.

The Earth's magnetic field is affected by the presence of heavy military armored vehicles which creates an additional magnetic moment. This distortion of the magnetic field, can be detected using magnetoresistive structures. This article touches base on the possibility of using semiconductor material such as InSe for high precision measurement of the magnetic field. The properties of InSe structures with regard to electrical, magnetic and optical characteristics are discussed. The effect of sharp anisotropy of InSe layered structure which consists in the strong covalent bond within the layers and a weak van-der-Waals bond in the interlayer space is discussed with regard to the explanation of how electrical, magnetic and optical properties are altered. The peculiarity of the spatial orientation of the material with regard to the direction of the magnetic field is considered. The impact of intercalation of InSe, GaSe by various concentrations of metal impurities such as nickel and other elements of 3d iron group is studied. Bode diagrams for pure InSe system are compared with the ones of NixInSe (for various x values). Also the effect of different temperatures ranging from room temperature to liquid nitrogen on the pattern of Bode diagrams is analyzed. The extent of how the magnetic properties of semiconductor crystals of the A3B6 type are altered by the presence of the metal impurities and their concentration is analyzed. Theoretic background for this paper is based on a well-known statement that layer structures such InSe or other A3B6 structures can be viewed as quasi two-dimensional. So, layers with strong covalent bond are formed by In-Se atoms, whereas interlayer space is filled with a weak Van der Waals bond. Within this model the processes across the layers can be described as a perturbation to the ones along the layers. This causes a strong anisotropy of the properties of these structures. Military implication of InSe structures mentioned throughout this paper is that these structures possess magnetoresistive properties and they were proved to be useful for the components of the magnetic sensors of civil and military use. This paper also touches base on how the InSe semiconductor crystals intercalated by 3d-elements can extend the functionality of magnetic sensors designed for heavy armor detection.

We study the properties and mass distributions of ultramagnetized nuclei produced as a result of heavy ion collisions, inside magnetar crust, explosions of type II supernovas, and the merging of neutron stars. For magnetic field strengths ranging from 0.1 to 10 TT, the Zeeman effect results in a linear nuclear magnetic response that can be described using magnetic susceptibility. Binding energies rise correspondingly for nuclei with open shells and fall for nuclei with closed shells. A noticeable increase in the generation of corresponding explosion nucleosynthetic products with antimagic numbers is predicted for nuclei belonging to the iron group and the r-process. The magnetic enhancement of 44Ti isotopes is consistent with results from observations and testifying to the substantial increase in the share of the main titanium isotope (48Ti) in the Galaxy’s chemical composition. An increased number of nuclides with low mass numbers is predicted in the peak of the r-process as a result of magnetic effects.

Electrooxidation of NH3 has gained extensive attention for energy and environmental applications such as fuel cells and water purification. Pt-based precious metal alloy catalysts have been intensi...

CuY and CuMY (M = Fe, Co, Ni) catalysts were prepared by modified vapor impregnation using cupric acetylacetonate as copper source and M acetylacetonate as promoter. The catalysts were evaluated in heterogeneous catalytic vapor phase oxidative carbonylation of methanol to dimethyl carbonate (DMC). The catalyst samples were analyzed by XRD, H2-TPR, XPS, CO-TPD, and NH3‑TPD, and their catalytic performance was assessed in a fixed-bed reactor. The experimental results indicate that all introduced species were well dispersed on zeolite Y, and the addition of iron group promoters have effect on the Cu+ contents, acidity and CO adsorption-desorption performance. Finally the influence of various promoters was examined with the aim of increasing space-time yield of DMC from methanol. Space-time yield of DMC was increased with the addition of iron group promoters in the order Fe < Co < Ni, but the selectivity follows the order of Fe < Ni < Co, respectively.

Energy storage and conversion may depend on the development of (photo)electrochemical devices relying on water oxidation. Finding electrode materials based on earth abundant elements is critical in this respect. Multinary transition metal oxides, such as the iron group spinels, can be efficient water oxidation electrocatalysts in alkaline media. Both Ni-rich and Fe-rich nickel ferrites have been synthesized through a chemical bath method by selecting specific bath temperature and composition. These electrodes, constituted by nanosheets, have been modified by the incorporation of phosphorus (as phosphate) in the structure, leading to either a substantial decrease (of around 0.1 V) in the overvoltage for oxygen evolution or a drastic decrease in the Tafel slope. Phosphate seems to have a dual role: it stabilizes the high oxidation states of surface nickel and probably provides sites for fast proton transfer. Both factors are needed for an efficient oxygen evolution reaction. This work has been financially supported by the Spanish Ministry of Science, Innovation and Universities under project RTI2018e102061eBeI00 (FONDOS FEDER). FJP also acknowledges the Spanish Ministry of Education for the award of an FPU grant.

Electrochemical nitrogen reduction reaction (NRR) is considered as an alternative to the industrial Haber-Bosch process for NH3 production due to both low energy consumption and environment friendliness. However, the major problem of electrochemical NRR is the unsatisfied efficiency and selectivity of electrocatalyst. As one group of the cheapest and most abundant transition metals, iron-group (Fe, Co, Ni and Cu) electrocatalysts show promising potential on cost and performance advantages as ideal substitute for traditional noble-metal catalysts. In this minireview, we summarize recent advances of iron-group-based materials (including their oxides, hydroxides, nitrides, sulfides and phosphides, etc.) as non-noble metal electrocatalysts towards ambient N2-to-NH3 conversion in aqueous media. Strategies to boost NRR performances and perspectives for future developments are discussed to provide guidance for the field of NRR studies.

The properties and mass distribution of the ultramagnetized atomic nuclei which arise in heavy-ion collisions and magnetar crusts, during Type II supernova explosions and neutron star mergers are analyzed. For the magnetic field strength range of 0.1&ndash, 10 teratesla, the Zeeman effect leads to a linear nuclear magnetic response that can be described in terms of magnetic susceptibility. Binding energies increase for open shell and decrease for closed shell nuclei. A noticeable enhancement in theyield of corresponding explosive nucleosynthesis products with antimagic numbers is predicted for iron group and r-process nuclei. Magnetic enrichment in a sampleof 44Ti corroborate theobservational results and imply a significant increase in the quantity of the main titanium isotope, 48Ti, in the chemical composition of galaxies. The enhancement of small mass number nuclides in the r-process peak may be due to magnetic effects.

International audience; The study of the transition from high-entropy alloys (HEAs) to conventional alloys (CAs) composed of the same alloying components is apparently important, both for understanding the formation of HEAs and for proper evaluation of their potential with respect to that of the corresponding CAs. However, this transition has thus far been studied in only two types of alloy systems: crystalline alloys of iron group metals (such as the Cantor alloy and its derivatives) and both amorphous (a-) and crystalline alloys, TE-TL, of early (TE = Ti, Zr, Nb, Hf) and late (TL = Co, Ni, Cu) transition metals. Here, we briefly overview the main results for the transition from HEAs to CAs in these alloy systems and then present new results for the electronic structure (ES), studied with photoemission spectroscopy and specific heat, atomic structure, thermal, magnetic and mechanical properties of a-TE-TL and Cantor-type alloys. A change in the properties of the alloys studied on crossing from the HEA to the CA concentration range mirrors that in the ES. The compositions of the alloys having the best properties depend on the alloy system and the property selected. This emphasizes the importance of knowing the ES for the design of new compositional complex alloys with the desired properties.

The specifics of hysteresis properties of antiferro-/ferromagnetic exchange-coupled film structures of the Fe50Mn50/FM type, where FM = Co, Fe, Ni, Fe20Ni80, Fe11Ni89, and Co30Ni70, are investigated. The angular dependences of the exchange bias fields and coercive force in ferromagnetic layers with different crystal structures, crystal magnetic anisotropy, and magnetostriction are obtained. Using a modified Stoner–Wohlfarth model, a computer simulation of hysteresis loops that allows for evaluation of the influence of various factors on the character of the magnetization reversal process is performed.

Data on cosmic ray muon bundles accumulated at the NEVOD-DECOR complex over the period from May 2012 to December 2018 have been analyzed. Local muon density spectra at various zenith angles have been reconstructed and compared with CORSIKA-based simulations. At large zenith angles and high muon multiplicities corresponding to primary particle energies more than about 3 × 1017 eV an excess of multi-muon events compared to simulations is clearly seen. Present data are compatible with the expectation for recent LHC-adjusted hadron interaction models only under assumption of extremely heavy (iron group nuclei) primary composition. The assumption of a heavy composition is however in contradiction with other EAS observables, such as maximum depth and its fluctuations.

Iron group transition metal phosphides (TMPs, M= Fe, Co, Ni) have been considered as promising noble-metal-free cocatalysts for the photocatalytic hydrogen (H2) generation. However, the impact on the H2 generation activity in correlation with the types of metal in TMPs still remains unresolved. In this paper, to investigate the effect of metal phosphides with different metal on photocatalytic H2 generation, three types of iron group transition metal phosphides (M2P, M=Fe, Co, and Ni) nanoparticles were used as the cocatalysts of sulfur doped g-C3N4 (S CN) for the photocatalytic H2 generation. By comparing three types of M2P/S CN, the optimum cocatalyst of Ni2P has ca. 22.7 times that of the pristine S CN under the same condition. The photoluminescence (PL) spectra, photoelectrochemical characterization and DFT calculations confirmed the enhanced photo-induced charge transfer and band separation when S CN was integrated with the Ni2P.

The research on supernovae explosions is one of the most exciting fields in astrophysics. Recent studies show that the electron capture and beta decay play key roles in supernovae explosions. In this paper, the half-lives of some iron group nuclei by β − -decay are investigated due to shell effect, pair effect, and the changes of the decay energy. We also discuss the influence of strong electron screening (SES) on the electron energy, beta decay threshold energy, and the antineutrino energy loss rates (AELR) in β − decay. The AELR increases, and the screening enhancement factor can get to 4.684 in SES due to Q-value correction, shell and pairing effect. The AELR can be suppressed at lower density and higher temperature environment (e.g., 0.1 30). The screening enhancement factor decreases about 14.10% (e.g., for 56Ni).

Accurate atomic data for line wavelengths, energy levels, line broadening such as hyperfine structure and isotope structure, and f-values, particularly for the line rich iron group elements, are needed for stellar astrophysics applications, and examples of recent measurements are given. These atomic data are essential for determination of elemental abundances in astronomical objects. With modern facilities, telescopes and spectrographs, access to underexplored regions (IR, UV, VUV), and improved stellar atmosphere models (3D, NLTE), and extremely large datasets, astronomers are tackling problems ranging from studying Galactic chemical evolution, to low mass stars and exoplanets. Such advances require improved accuracy and completeness of the atomic database for analyses of astrophysical spectra.

To rational design non-noble catalysts with oxygen reduction reaction (ORR) activity and durability superior to that of Pt/C, we report the fabrication of iron group metal sulphides immobilized inside hierarchically porous N,S-enriched carbon architecture using a facile double-phase encapsulation approach followed by a pyrolysis process. The as-prepared hybrid architectures exhibit significantly enhanced electrocatalytic activity towards the ORR, including a positive onset potential, low Tafel slope, and high electron transfer number. In particular, the ORR activity of FeS@G/NSC is even superior to that of the Pt/C benchmark, which possesses an outstanding onset potential (0.99 V vs RHE) and a high discharge voltage plateau (∼1.47 V at discharge current density of 50 mA cm−2 in the Al-air battery test) with excellent stability. These hybrid carbon architectures provide a new direction for carbon-based ORR electrocatalysts performance optimization for next-generation air batteries.

The present thesis reports on the development of iron group metal-catalyzed hydrogenation reactions. Specifically, mechanistic investigations have been focused to develop better catalysts in future. Chapter 1 advocates kinetic poisoning experiments for the distinction between homogeneous and heterogeneous catalysis with standard laboratory equipment. Chapter 2 reviews dibenzo[a,e]cyclooctatetraene, a typical homogeneous catalyst poison. Simple cobalt catalysts for C=C, C=O, and C=N hydrogenations have been developed in Chapter 3: Olefinic substrates stabilize the reduction of cobalt salts to obtain cobalt nanoparticles. Chapter 4 describes homogeneous hydrogenation catalysts for alkene and imine hydrogenation based on highly-reduced cobaltates. The redoxactive ligand bis(imino)acenaphthene (BIAN) allowed the isolation and detailed mechanistic analyses of olefin cobaltate and hydride intermediates. Related cobaltate catalysts have been developed for amine-borane (de)hydrogenations and transfer hydrogenations to imines, chinolines and alkenes in Chapter 5. Chapter 6 reports on the synthesis, characterization and catalysis of a dimeric iron ate complex with four bridging hydrides. In Chapter 7, olefin-stabilized nickel nanoparticle catalysts have been developed for alkene hydrogenation based on a nickel metalate. These catalysts exhibit a remarkable functional group tolerance. Chapter 8 highlights recent studies by the groups of Bedford and Neidig for ironcatalyzed cross-coupling reactions by triorganoferrates as active species. Chapter 9 summarizes the results of this thesis., Diese Dissertation handelt von der Erforschung neuer Hydrierkatalysatoren der Eisengruppe. Dabei wurde ein besonderer Fokus auf den Mechanismus gelegt, um zukünftig bessere Katalysatoren zu entwickeln. Kapitel 1 berichtet über kinetische Vergiftungsstudien, um die Unterscheidung zwischen homogener und heterogener Katalyse mit möglichst einfachen Laborgeräten zu bewerkstelligen. Kapitel 2 bietet einen Überblick über Dibenzo[a,e]cyclooctatetraene, ein typisches homogenes Vergiftungsreagenz. Ein möglichst einfacher Kobaltkatalysator für die Hydrierung von C=C-, C=O-, and C=N-Bindungen wurde in Kapitel 3 entwickelt: Olefinische Substrate oder Anthracen stabilisieren die Reduktion von Kobaltsalzen, um Nanopartikel zu erhalten. Der redoxaktive Ligand Bis(imino)acenaphthen (BIAN) ermöglicht die in Kapitel 4 beschriebene Stabilisierung von Olefin- und Hydridokobaltaten. Diese wurden in der katalytischen Hydrierung von Olefinen und Iminen unter milden Bedingungen eingesetzt. Weiterhin bietet die Isolierung dieser Modellkomplexe wertvolle Einblicke in die Identität des aktiven Katalysators. In Kapitel 5 wurden verwandte Kobaltate in der katalytischen Dehydrierung von Amminboranen eingesetzt. Zudem konnten diese Katalysatoren für die Transferhydrierung von Iminen, Chinolinen und Alkenen eingesetzt werden. Präparativ konnte so auf Hochdruckapparaturen verzichtet werden. Kapitel 6 beschreibt die Synthese eines Ferratdimers mit vier verbrückenden Hydridoliganden. Dieser Komplex konnte erfolgreich in der Hydrierung von anspruchsvollen Alkenen eingesetzt werden. In Kapitel 7 wird die Entwicklung eines Hydrierkatalysators durch Hydrogenolyse eines Nickelmetallates beschrieben. Dieser verfügt über eine außerordentliche funktionelle Gruppentoleranz. Kapitel 8 diskutiert eindrucksvolle Arbeiten über eisenkatalysierte Kreuzkupplungen der Gruppen Bedford und Neidig. Ihre Ergebnisse weisen auf Triorganoferrate als aktive Spezies in diesen Reaktionen hin. Kapitel 9 fasst die Ergebnisse dieser Dissertation zusammen.

Electrodeposition of earth-abundant iron group metals such as nickel is difficult to characterize by simple electrochemical analyses since the reduction of their metal salts often competes with inhibiting reactions. This makes the mechanistic interpretation sometimes contradictory, preventing unambiguous predictions about the nature and structure of the electrodeposited material. Herein, the complexity of Ni nanoparticles (NPs) electrodeposition on indium tin oxide (ITO) is unraveled operando and at a single entity NP level by optical microscopy correlated to ex situ SEM imaging. Our correlative approach allows differentiating the dynamics of formation of two different NP populations, metallic Ni and Ni(OH)2 with a

The cause of the microscopic size effect in the microhardness of electroplated binary alloys between iron group metals and tungsten is identified by studying electrodeposition of Co-W alloys. The effect is caused by the presence of oxygen-containing impurities in electroplated alloys, the impurity content growing with increasing the volume current density, which leads to a reduction in the coating microhardness. We find that the nature of anodes used affects the properties of deposited coatings, in particular, microhardness, because a deposition-inducing metal complex, which is a complex of an iron group metal, is consumed during electrolysis not only at the cathode, but it may also undergo oxidation at the anode, which identifies the way the anode affects the coating properties.

A series of iron, cobalt and nickel metal phosphides of chemical formula FexP, Co2P and Ni2P with high specific surface areas of 331.1, 294.2 and 228.0 m2 g−1, respectively, was firstly synthesized...

—Samples of arrays of nanowires are produced from iron, iron–cobalt and iron–nickel alloys via matrix synthesis based on polymer track membranes with pore diameters ranging from 30 to 300 nm. The influence of stress and pore diameter on the galvanic process and structure of nanowires is studied. The arrays of nanowires are examined by microscopy and X-ray diffraction. The magnetic properties are inspected via magnetometry and Mossbauer spectroscopy. The angular dependences of hysteresis loop shape are obtained and comprehensively discussed. As shown, decreasing the growth stress and/or increasing the pore diameter make the Mossbauer spectra of nanowires similar to those of bulk materials. Furthermore, the higher the growth stress is, the larger is the coercive force of nanowires. For the studied species of nanomaterials, the ability to control the magnetic properties during the synthesis is shown, as well.

A method for assessing the selectivity of active centers upon sorption of sorbates from multicomponent solutions containing three or more pollutants is proposed. The method is based on comparison of the values of specific sorbent capacity for each of the sorbates when they are extracted from single-pollutant (one pollutant) and multipollutant (all contaminants simultaneously) solutions. Both stationary and flowing solutions to be studied contained close and significantly different initial concentrations of eco-pollutants. At the first stage, stationary solutions contained a single pollutant (then all three at the same time) at a given equal (close) initial concentration, the sorbent mass in them being fixed strictly. At a given moment of time ф i, the capacity of the sorbent Qi for each sorbate is estimated. Then the same experiment is carried out with the solutions containing all three pollutants simultaneously. If Qi ( ф i = const) does not depend on the presence of other pollutants, then the selectivity of the active centers of the sorbent takes place. If it decreases with the introduction of other pollutants, the selectivity is absent. At the second stage, the same experiment is carried out in the flow solutions, and at the third stage at the concentration of one the sorbate (10 – 100 times) lower than that of others (flow media). In all cases, the value Qi of each i-th sorbate is also estimated and the same theoretical analysis is carried out. Results of sorption of metal cations (Me (II)) (iron group) on glauconite at practically identical their initial concentrations and Ni (II) from media with high (more than 100-fold) content of hardness cations (Ca (II) and Mg (II)) are presented as an example. The high selectivity of the active sorbent centers is shown.

With the increasing energy demand, energy conversion and storage technology has garnered intense attention. As one of the competitive electrochemical energy technologies, the zinc–air battery (ZAB) has been considered to be a promising candidate due to its advantages, including low cost and environmental friendliness. To overcome its technical challenges of low activity and stability of ZAB air electrode electrocatalysts, substantial efforts have been made to develop highly active and stable materials for improving the performance. In this paper, a comprehensive review of one type of the ZAB electrocatalyst, that is, iron group (Fe, Co, Ni)-based oxides, is provided. The discussion will be concentrated on the recent progress and challenges associated with this type of electrocatalyst as well as corresponding perspectives.

A method for the matrix calculation of the spectral characteristics of AII–BVI semiconductors doped with iron-group ions is proposed, which takes into account all possible interactions in the ion and the effect of intramolecular surrounding fields of different symmetries. A technique for calculating the oscillator strength on the basis of eigenfunctions of the resulting states of 3d7, 3d8, and 3d6 electron configurations is developed. The spectral regularities of the Co2+, Ni2+, and Fe2+ energy structures for the ZnO, ZnS, ZnSe, ZnTe, CdO, CdS, CdSe, and CdTe materials are studied. All possible spectral bands in iron-group ions implanted in AII–BVI semiconductors in the range of 1.3–3 μm are established. The possibility of implementing the laser effect on these materials is estimated.

Metallic glasses (MGs) have recently attracted great attention in degrading azo dyes and other organic pollutants as a kind of environmental-friendly materials for wastewater remediation. In this paper, decolorization properties of MGs based on different iron-group elements (IGEs) were reported, and adsorption or reductive degradation of aqueous azo dye solutions was observed on the surface of glassy ribbons due to their different main constituents. The primary factor determining the occurrence of adsorption or degradation was considered to be the electronic nature of the MGs instead of their crystalline structures or surface states. Besides, some electrochemical information of the glassy ribbons in the azo dye solutions was also provided for understanding the mechanism of the decolorization process. Our findings suggest that such MGs based on IGEs may be good candidates for preparing tailored materials to treat azo dye solutions or other similar organic solutions.