Electrochemical surface nitriding of pure iron by molten salt electrochemical process

Energy Technology Data Exchange (ETDEWEB)

Tsujimura, Hiroyuki; Goto, Takuya; Ito, Yasuhiko

2004-08-11

Electrochemical surface nitriding of pure iron was investigated in molten LiCl-KCl-Li{sub 3}N systems at 773 K. An outer compound layer and an inner diffusion layer were obtained by means of potentiostatic electrolysis at 1.00 V (versus Li{sup +}/Li). From XRD and SEM analyses, it was confirmed that the obtained compound layer consisted of {epsilon}-Fe{sub 2-3}N and {gamma}'-Fe{sub 4}N; the free energies of formation of the two nitrides are positive and the equilibrium nitrogen partial pressure of those are of the order of 10{sup 4} atm at 773 K. This result suggests that an apparent nitrogen partial pressure of at least the order of 10{sup 4} atm was imposed by the adsorbed nitrogen atoms (N{sub ads}) formed by anodic oxidation of nitride ion (N{sup 3-}) at the iron electrode surface.

Oxide Dispersion Strengthened Iron Aluminide by CVD Coated Powders

Energy Technology Data Exchange (ETDEWEB)

Asit Biswas Andrew J. Sherman

2006-09-25

This I &I Category2 program developed chemical vapor deposition (CVD) of iron, aluminum and aluminum oxide coated iron powders and the availability of high temperature oxidation, corrosion and erosion resistant coating for future power generation equipment and can be used for retrofitting existing fossil-fired power plant equipment. This coating will provide enhanced life and performance of Coal-Fired Boilers components such as fire side corrosion on the outer diameter (OD) of the water wall and superheater tubing as well as on the inner diameter (ID) and OD of larger diameter headers. The program also developed a manufacturing route for readily available thermal spray powders for iron aluminide coating and fabrication of net shape component by powder metallurgy route using this CVD coated powders. This coating can also be applid on jet engine compressor blade and housing, industrial heat treating furnace fixtures, magnetic electronic parts, heating element, piping and tubing for fossil energy application and automotive application, chemical processing equipment , heat exchanger, and structural member of aircraft. The program also resulted in developing a new fabrication route of thermal spray coating and oxide dispersion strengthened (ODS) iron aluminide composites enabling more precise control over material microstructures.

Nitrogen uptake and rate-limiting step in low-temperature nitriding of iron

NARCIS (Netherlands)

Inia, DK; Vredenberg, AM; Habraken, FHPM; Boerma, DO

1999-01-01

Recently, a method to nitride iron in NH3 ambients at low temperature (225-350 degrees C) has been developed. In this method, the Fe is covered with a thin (similar to 40 nm) Ni layer, which acts as a catalyst for the nitriding process. From experiments, in which the amount of nitrogen uptake is

Magnetic microparticles post-synthetically coated by hyaluronic acid as an enhanced carrier for microfluidic bioanalysis

International Nuclear Information System (INIS)

Holubova, Lucie; Knotek, Petr; Palarcik, Jiri; Cadkova, Michaela; Belina, Petr; Vlcek, Milan; Korecka, Lucie; Bilkova, Zuzana

2014-01-01

Iron oxide based particles functionalized by bioactive molecules have been utilized extensively in biotechnology and biomedicine. Despite their already proven advantages, instability under changing reaction conditions, non-specific sorption of biomolecules on the particles' surfaces, and iron oxide leakage from the naked particles can greatly limit their application. As confirmed many times, surface treatment with an appropriate stabilizer helps to minimize these disadvantages. In this work, we describe enhanced post-synthetic surface modification of superparamagnetic microparticles varying in materials and size using hyaluronic acid (HA) in various chain lengths. Scanning electron microscopy, atomic force microscopy, phase analysis light scattering and laser diffraction are the methods used for characterization of HA-coated particles. The zeta potential and thickness of HA-layer of HA-coated Dynabeads M270 Amine were − 50 mV and 85 nm, respectively, and of HA-coated p(GMA-MOEAA)-NH 2 were − 38 mV and 140 nm, respectively. The electrochemical analysis confirmed the zero leakage of magnetic material and no reactivity of particles with hydrogen peroxide. The rate of non-specific sorption of bovine serum albumin was reduced up to 50% of the naked ones. The coating efficiency and suitability of biopolymer-based microparticles for magnetically active microfluidic devices were confirmed. - Highlights: • Post-synthetic surface modification of magnetic microparticles by hyaluronic acid • Hyaluronic acid — polymer of unique physicochemical and biological characteristics • Panel of particle characterization methods was introduced. • HA-coated microparticles gain characteristics suited for microfluidic bioanalysis

The convenient preparation of stable aryl-coated zerovalent iron nanoparticles

Directory of Open Access Journals (Sweden)

Olga A. Guselnikova

2015-05-01

Full Text Available A novel approach for the in situ synthesis of zerovalent aryl-coated iron nanoparticles (NPs based on diazonium salt chemistry is proposed. Surface-modified zerovalent iron NPs (ZVI NPs were prepared by simple chemical reduction of iron(III chloride aqueous solution followed by in situ modification using water soluble arenediazonium tosylate. The resulting NPs, with average iron core diameter of 21 nm, were coated with a 10 nm thick organic layer to provide long-term protection in air for the highly reactive zerovalent iron core up to 180 °C. The surface-modified iron NPs possess a high grafting density of the aryl group on the NPs surface of 1.23 mmol/g. FTIR spectroscopy, XRD, HRTEM, TGA/DTA, and elemental analysis were performed in order to characterize the resulting material.

Method of coating an iron-based article

Science.gov (United States)

Magdefrau, Neal; Beals, James T.; Sun, Ellen Y.; Yamanis, Jean

2016-11-29

A method of coating an iron-based article includes a first heating step of heating a substrate that includes an iron-based material in the presence of an aluminum source material and halide diffusion activator. The heating is conducted in a substantially non-oxidizing environment, to cause the formation of an aluminum-rich layer in the iron-based material. In a second heating step, the substrate that has the aluminum-rich layer is heated in an oxidizing environment to oxidize the aluminum in the aluminum-rich layer.

Repair welding of cast iron coated electrodes

Science.gov (United States)

Żuk, M.; Górka, J.; Dojka, R.; Czupryński, A.

2017-08-01

Welding cast iron is a complex production procedure. Repair welding was used to repair damaged or poorly made castings. This is due to a tendency to cracking of the material during welding as well as after it. Welding cast iron can be carried out on hot or on cold. Hot welding requires high heat material and the use of welding material in the form of cast iron. In the case of cold welding, it is possible to use different materials. Mostly used filler metals are nickel and copper based. The work shows the course of research concerning repairmen of ductile iron with arc welding method. For the reparation process four types of ESAB company coated electrodes dedicated for cast iron were used with diameter 3.2 and 4 mm: ES 18-8-6B (4mm), EB 150 (4mm), OK NiCl, EŻM. In the cast iron examined during the testing grooves were made using plasma methods, in order to simulate the removed casting flaws. Then the welding process with coated electrodes was executed. The process utilized low welding current row of 100A, so there would only be a small amount of heat delivered to the heat affected zone (HAZ). Short stitches were made, after welding it was hammered, in order to remove stresses. After the repair welding the part of studies commenced which purpose was finding surface defects using visual testing (VT) and penetration testing (PT). In the second part, a series of macro and microscopic studies were executed witch the purpose of disclosuring the structure. Then the hardness tests for welds cross sections were performed. An important aspect of welding cast iron is the colour of the padding weld after welding, more precisely the difference between the base material and padding weld, the use of different materials extra gives the extra ability to select the best variant. The research of four types of coated electrode was executed, based on the demands the best option in terms of aesthetic, strength and hardness.

Microwave-Assisted Combustion Synthesis of Nano Iron Oxide/Iron-Coated Activated Carbon, Anthracite, Cellulose Fiber, and Silica, with Arsenic Adsorption Studies

Directory of Open Access Journals (Sweden)

Mallikarjuna N. Nadagouda

2011-01-01

Full Text Available Combustion synthesis of iron oxide/iron coated carbons such as activated carbon, anthracite, cellulose fiber, and silica is described. The reactions were carried out in alumina crucibles using a Panasonic kitchen microwave with inverter technology, and the reaction process was completed within a few minutes. The method used no additional fuel and nitrate, which is present in the precursor itself, to drive the reaction. The obtained samples were then characterized with X-ray mapping, scanning electron microscopy (SEM, energy dispersive X-ray analysis (EDS, selected area diffraction pattern (SAED, transmission electron microscopy (TEM, X-ray diffraction (XRD, and inductively coupled plasma (ICP spectroscopy. The size of the iron oxide/iron nanoparticle-coated activated carbon, anthracite, cellulose fiber, and silica samples were found to be in the nano range (50–400 nm. The iron oxide/iron nanoparticles mostly crystallized into cubic symmetry which was confirmed by SAED. The XRD pattern indicated that iron oxide/iron nano particles existed in four major phases. That is, γ-Fe2O3, α-Fe2O3, Fe3O4, and Fe. These iron-coated activated carbon, anthracite, cellulose fiber, and silica samples were tested for arsenic adsorption through batch experiments, revealing that few samples had significant arsenic adsorption.

Model of the Alphinising Coating Crystallisation on Iron Alloys

Directory of Open Access Journals (Sweden)

S. Pietrowski

2007-07-01

Full Text Available The study presents a hypothetical model of crystallisation of the alphinising coating produced on iron alloys by immersion in the bath of silumin. Basing on a wide-range of experiments and investigations, the effect of the type of inserted material (“armco” iron, C45 steel, grey cast iron and nodular graphite cast iron and of the technological regime of the alphinising process (chemical composition of silumin bath, its temperature, the time of holding an insert in the bath, and the insert surface roughness height “Rz” on the coating structure was determined. The type of the coating structure was established by metallographic examinations carried out by optical microscopy, electron transmission microsopy and scanning electron microscopy, using additionally an X-ray microanalyser and X-ray diffraction patterns. The results of these investigations were described in [1÷7]. Basing on the obtained results, a probable model of the crystallisation of an alphi-nising coating on iron alloys, produced by immersion in the alphinising bath, was developed. It has been stated that, most probably, the alphinising process begins when the insert reaches its contact temperature “ts”.. Since that moment, due to the wetting process and convec-tion movement of bath around the insert surface, an intense process of the dissolution starts. A reactive diffusion of the atoms of Fe and Si from the insert to the bath and of the atoms of Al and Si from the bath to the insert takes place. An intermetallic Al3Fe phase is crystallis-ing on the steel, while on the cast iron, a silicon carbide Fe4CSi is growing, probably due to carbon diffusion from graphite. Then, on the steel, as an effect of the peritectic reaction, are successively crystallising the phases of Al12Fe3Si2 and Al9Fe3Si2. The Al3Fe phase probably crystallises on the cast iron to be transformed later, due to peritectic reaction, into an Al12Fe3Si2 phase on which the Al9Fe3Si2 phase will be growing

The detection of HBV DNA with gold-coated iron oxide nanoparticle gene probes

International Nuclear Information System (INIS)

Xi Dong; Luo Xiaoping; Lu Qianghua; Yao Kailun; Liu Zuli; Ning Qin

2008-01-01

Gold-coated iron oxide nanoparticle Hepatitis B virus (HBV) DNA probes were prepared, and their application for HBV DNA measurement was studied. Gold-coated iron oxide nanoparticles were prepared by the citrate reduction of tetra-chloroauric acid in the presence of iron oxide nanoparticles which were added as seeds. With a fluorescence-based method, the maximal surface coverage of hexaethiol 30-mer oligonucleotides and the maximal percentage of hybridization strands on gold-coated iron oxide nanoparticles were (120 ± 8) oligonucleotides per nanoparticle, and (14 ± 2%), respectively, which were comparable with those of (132 ± 10) and (22 ± 3%) in Au nanoparticle groups. Large network aggregates were formed when gold-coated iron oxide nanoparticle HBV DNA gene probe was applied to detect HBV DNA molecules as evidenced by transmission electron microscopy and the high specificity was verified by blot hybridization. Our results further suggested that detecting DNA with iron oxide nanoparticles and magnetic separator was feasible and might be an alternative effective method

Doxorubicin loaded PVA coated iron oxide nanoparticles for targeted drug delivery

International Nuclear Information System (INIS)

Kayal, S.; Ramanujan, R.V.

2010-01-01

Magnetic drug targeting is a drug delivery system that can be used in locoregional cancer treatment. Coated magnetic particles, called carriers, are very useful for delivering chemotherapeutic drugs. Magnetic carriers were synthesized by coprecipitation of iron oxide followed by coating with polyvinyl alcohol (PVA). Characterization was carried out using X-ray diffraction, TEM, TGA, FTIR and VSM techniques. The magnetic core of the carriers was magnetite (Fe 3 O 4 ), with average size of 10 nm. The room temperature VSM measurements showed that magnetic particles were superparamagnetic. The amount of PVA bound to the iron oxide nanoparticles were estimated by thermogravimetric analysis (TGA) and the attachment of PVA to the iron oxide nanoparticles was confirmed by FTIR analysis. Doxorubicin (DOX) drug loading and release profiles of PVA coated iron oxide nanoparticles showed that up to 45% of adsorbed drug was released in 80 h, the drug release followed the Fickian diffusion-controlled process. The binding of DOX to the PVA was confirmed by FTIR analysis. The present findings show that DOX loaded PVA coated iron oxide nanoparticles are promising for magnetically targeted drug delivery.

Cyanide Ligand Assembly by Carbon Atom Transfer to an Iron Nitride

International Nuclear Information System (INIS)

Martinez, Jorge L.; Pink, Maren

2017-01-01

The new iron(IV) nitride complex PhB( i Pr 2 Im) 3 Fe≡N reacts with two equivalents of bis(diisopropylamino)cyclopropenylidene (BAC) to provide PhB( i Pr 2 Im) 3 Fe(CN)(N 2 )(BAC). This unusual example of a four-electron reaction involves carbon atom transfer from BAC to create a cyanide ligand along with the alkyne i Pr 2 N-C≡C-N i Pr 2 . The iron complex is in equilibrium with an N 2 - free species. Further reaction with CO leads to formation of a CO analogue, which can be independently prepared using NaCN as the cyanide source, while reaction with B(C 6 F 5 ) 3 provides the cyanoborane derivative.

Investigating Tribological Characteristics of HVOF Sprayed AISI 316 Stainless Steel Coating by Pulsed Plasma Nitriding

Science.gov (United States)

Mindivan, H.

2018-01-01

In this study, surface modification of aluminum alloy using High-Velocity Oxygen Fuel (HVOF) thermal spray and pulsed plasma nitriding processes was investigated. AISI 316 stainless steel coating on 1050 aluminum alloy substrate by HVOF process was pulsed plasma nitrided at 793 K under 0.00025 MPa pressure for 43200 s in a gas mixture of 75 % N2 and 25 % H2. The results showed that the pulse plasma nitriding process produced a surface layer with CrN, iron nitrides (Fe3N, Fe4N) and expanded austenite (γN). The pulsed plasma nitrided HVOF-sprayed coating showed higher surface hardness, lower wear rate and coefficient of friction than the untreated HVOF-sprayed one.

Chemical environment of iron atoms in iron oxynitride films synthesized by reactive magnetron sputtering

International Nuclear Information System (INIS)

Grafoute, M.; Petitjean, C.; Rousselot, C.; Pierson, J.F.; Greneche, J.M.

2007-01-01

An iron oxynitride film was deposited on silicon and glass substrates by magnetron sputtering in an Ar-N 2 -O 2 reactive mixture. Rutherford back-scattering spectrometry was used to determine the film composition (Fe 1.06 O 0.35 N 0.65 ). X-ray diffraction revealed the formation of a face-centred cubic (fcc) structure with a lattice parameter close to that of γ'''-FeN. X-ray photoelectron spectroscopy showed the occurrence of Fe-N and Fe-O bonds in the film. The local environment of iron atoms studied by 57 Fe Moessbauer spectrometry at both 300 and 77 K gives clear evidence that the Fe 1.06 O 0.35 N 0.65 is not a mixture of iron oxide and iron nitride phases. Despite a small amount of an iron nitride phase, the main sample consists of an iron oxynitride phase with an NaCl-type structure where oxygen atoms partially substitute for nitrogen atoms, thus indicating the formation of a iron oxynitride with an fcc structure

Nanocrystalline iron nitride films with perpendicular magnetic anisotropy

International Nuclear Information System (INIS)

Gupta, Ajay; Dubey, Ranu; Leitenberger, W.; Pietsch, U.

2008-01-01

Nanocrystalline α-iron nitride films have been prepared using reactive ion-beam sputtering. Films develop significant perpendicualr magnetic anisotropy (PMA) with increasing thickness. A comparison of x-ray diffraction patterns taken with scattering vectors in the film plane and out of the film plane provides a clear evidence for development of compressive strain in the film plane with thickness. Thermal annealing results in relaxation of the strain, which correlates very well with the relaxation of PMA. This suggests that the observed PMA is a consequence of the breaking of the symmetry of the crystal structure due to the compressive strain

Iron-based alloy and nitridation treatment for PEM fuel cell bipolar plates

Science.gov (United States)

Brady, Michael P [Oak Ridge, TN; Yang, Bing [Oak Ridge, TN; Maziasz, Philip J [Oak Ridge, TN

2010-11-09

A corrosion resistant electrically conductive component that can be used as a bipolar plate in a PEM fuel cell application is composed of an alloy substrate which has 10-30 wt. % Cr, 0.5 to 7 wt. % V, and base metal being Fe, and a continuous surface layer of chromium nitride and vanadium nitride essentially free of base metal. A oxide layer of chromium vanadium oxide can be disposed between the alloy substrate and the continuous surface nitride layer. A method to prepare the corrosion resistant electrically conductive component involves a two-step nitridization sequence by exposing the alloy to a oxygen containing gas at an elevated temperature, and subsequently exposing the alloy to an oxygen free nitrogen containing gas at an elevated temperature to yield a component where a continuous chromium nitride layer free of iron has formed at the surface.

Biocompatibility of chitosan-coated iron oxide nanoparticles with osteoblast cells

Directory of Open Access Journals (Sweden)

Shi S

2012-10-01

Full Text Available Si-Feng Shi,1 Jing-Fu Jia,2 Xiao-Kui Guo,3 Ya-Ping Zhao,2 De-Sheng Chen,1 Yong-Yuan Guo,1 Tao Cheng,1 Xian-Long Zhang11Department of Orthopedic Surgery, Shanghai Sixth People’s Hospital, School of Medicine, 2School of Chemistry and Chemical Technology, 3Department of Medical Microbiology and Parasitology, School of Medicine, Shanghai Jiao Tong University Shanghai, ChinaBackground: Bone disorders (including osteoporosis, loosening of a prosthesis, and bone infections are of great concern to the medical community and are difficult to cure. Therapies are available to treat such diseases, but all have drawbacks and are not specifically targeted to the site of disease. Chitosan is widely used in the biomedical community, including for orthopedic applications. The aim of the present study was to coat chitosan onto iron oxide nanoparticles and to determine its effect on the proliferation and differentiation of osteoblasts.Methods: Nanoparticles were characterized using transmission electron microscopy, dynamic light scattering, x-ray diffraction, zeta potential, and vibrating sample magnetometry. Uptake of nanoparticles by osteoblasts was studied by transmission electron microscopy and Prussian blue staining. Viability and proliferation of osteoblasts were measured in the presence of uncoated iron oxide magnetic nanoparticles or those coated with chitosan. Lactate dehydrogenase, alkaline phosphatase, total protein synthesis, and extracellular calcium deposition was studied in the presence of the nanoparticles.Results: Chitosan-coated iron oxide nanoparticles enhanced osteoblast proliferation, decreased cell membrane damage, and promoted cell differentiation, as indicated by an increase in alkaline phosphatase and extracellular calcium deposition. Chitosan-coated iron oxide nanoparticles showed good compatibility with osteoblasts.Conclusion: Further research is necessary to optimize magnetic nanoparticles for the treatment of bone disease

Structure and properties of composite iron-based coatings obtained by the electromechanical technique

Science.gov (United States)

Dubinskii, N. A.

2007-09-01

The influence of the electrolyte temperature and current density on the content of inclusions of powder particles in composite coatings obtained by the electrochemical technique has been investigated. It has been found that the wear resistance of iron coatings with inclusions of powder particles of aluminum, kaolin, and calcium silicate increases from 5 to 10 times compared to coating without inclusions of disperse particles, and the friction coefficient therewith decreases from 0.097 to 0.026. It has been shown that the mechanical properties of iron obtained by the method of electrochemical deposition depend on their fine structure. The regimes of deposition of iron-based coatings have been optimized.

Oral iron administration in suckling piglets – a review

Directory of Open Access Journals (Sweden)

Martin Svoboda

2018-01-01

Full Text Available Iron deficiency is presently a serious problem in suckling piglets on pig farms. The most often used method of anaemia prevention in piglets is parenteral administration of iron dextran. Oral iron represents an alternative to this method. The goal of this article is to review current knowledge on oral iron administration in suckling piglets. The substances that can be used for this purpose include iron dextran, iron salts, iron chelates, carbonyl iron, an iron polymaltose complex and iron microparticles. The different methods of oral iron administration in piglets are discussed.

Rheological characterization of a magnetorheological ferrofluid using iron nitride nanoparticles

Science.gov (United States)

Armijo, Leisha M.; Ahuré-Powell, Louise A.; Wereley, Norman M.

2015-05-01

Magnetorheology of a magnetorheological ferrofluid (MRFF) was investigated to study the role of a ferromagnetic nanoparticle (NP) additive in magnetorheological fluids (MRFs). Iron nitride (Fe16N2) NPs, nominally within the diameter range of ˜16-45 nm (spherical NPs) and ˜30-66 nm (cubic NPs), were coated with carboxy-polyethylene glycol (carboxy-PEG) and dispersed in silicone oil in order to produce a magnetic carrier fluid or ferrofluid for two solids loadings: 2 vol. % and 5 vol. %. Conventional spherical carbonyl iron (CI) particles, varying in diameter from 6 to 10 μm, were suspended in the ferrofluid at 25 vol. % solids loading. Rheological properties of the MRFF synthesized with the carboxy-PEG-based ferromagnetic carrier fluid were compared to the MRF synthesized with silicone oil to determine how ferrofluid can influence dynamic viscosity and yield stress. Rheological measurements of both MRF and MRFF samples were carried out using a Paar Physica 300 rheometer to estimate the field-off viscosity and to measure flow curves (i.e., shear stress vs. shear rate) as a function of magnetic field. A Bingham-plastic model was used to characterize the flow curves, and results show that there is an increase in the dynamic viscosity of the MRFF over the MRF. The ferromagnetic carrier fluid greatly increases yield stress as only 2 vol. % of added carboxy-PEG NPs improves the yield stress performance by almost 5%. A second MRFF sample synthesized with 5 vol. % of added carboxy-PEG NPs contained in the ferrofluid significantly enhanced the yield stress performance by 13% over the MRF at the same CI solids loading (25 vol. %).

Surface oxidation phenomena of boride coatings grown on iron

International Nuclear Information System (INIS)

Carbucicchio, M.; Palombarini, G.; Sambogna, G.

1992-01-01

Very hard boride coatings are grown on various metals using thermochemical as well as chemical vapour deposition techniques. In this way many surface properties, and in particular the wear resistance, can be considerably improved. Usually, also the corrosion behaviour of the treated components is important. In particular, oxidizing atmospheres are involved in many applications where, therefore, coating-environment interactions can play a relevant role. In a previous work, the early stages of the oxidation of iron borides were studied by treating single phase compacted powders in flowing oxygen at low temperatures (300-450deg C). In the present paper, the attention is addressed to the oxidation of both single phase and polyphase boride coatings thermochemically grown on iron. The single phase boride coatings were constituted by Fe 2 B, while the polyphase coatings were constituted by an inner Fe 2 B layer and an outer FeB-base layer. All the boride layers displayed strong (002) preferred crystallographic orientations. (orig.)

Solid-stabilized emulsion formation using stearoyl lactylate coated iron oxide nanoparticles

Science.gov (United States)

Vengsarkar, Pranav S.; Roberts, Christopher B.

2014-10-01

Iron oxide nanoparticles can exhibit highly tunable physicochemical properties that are extremely important in applications such as catalysis, biomedicine and environmental remediation. The small size of iron oxide nanoparticles can be used to stabilize oil-in-water Pickering emulsions due to their high energy of adsorption at the interface of oil droplets in water. The objective of this work is to investigate the effect of the primary particle characteristics and stabilizing agent chemistry on the stability of oil-in-water Pickering emulsions. Iron oxide nanoparticles were synthesized by the co-precipitation method using stoichiometric amounts of Fe2+ and Fe3+ salts. Sodium stearoyl lactylate (SSL), a Food and Drug Administration approved food additive, was used to functionalize the iron oxide nanoparticles. SSL is useful in the generation of fat-in-water emulsions due to its high hydrophilic-lipophilic balance and its bilayer-forming capacity. Generation of a monolayer or a bilayer coating on the nanoparticles was controlled through systematic changes in reagent concentrations. The coated particles were then characterized using various analytical techniques to determine their size, their crystal structure and surface functionalization. The capacity of these bilayer coated nanoparticles to stabilize oil-in-water emulsions under various salt concentrations and pH values was also systematically determined using various characterization techniques. This study successfully demonstrated the ability to synthesize iron oxide nanoparticles (20-40 nm) coated with SSL in order to generate stable Pickering emulsions that were pH-responsive and resistant to significant destabilization in a saline environment, thereby lending themselves to applications in advanced oil spill recovery and remediation.

Microwave-assisted combustion synthesis of nano iron oxide/iron-coated activated carbon, anthracite, cellulose fiber, and silica, with arsenic adsorption studies

Science.gov (United States)

Combustion synthesis of iron oxide/iron coated carbons such as activated carbon, anthracite, cellulose fiber and silica is described. The reactions were carried out in alumina crucibles using a Panasonic kitchen microwave with inverter technology, and the reaction process was com...

ε-iron nitrides: Intrinsic anomalous Hall ferromagnets

Directory of Open Access Journals (Sweden)

Guo-Ke Li

2015-02-01

Full Text Available The anomalous Hall effect in ε-iron nitrides (ε-Fe3-xN, 0 ≤ x ≤ 1 has been systematically investigated taking advantage of the fact that the exchange splitting of ε-Fe3-xN can be continuously tuned through the nitrogen concentration. It has been found that the anomalous Hall conductivity, σ x y A H , is proportional to the saturation magnetization MS, i.e., σ x y A H = S H M S , across significant variations in the saturation magnetization (96–1146 emu/cc. This relationship is in excellent agreement with the intrinsic mechanism as well as with the unified theory of AHE. Our results also demonstrate that the anomalous Hall conductivity is sensitive to the exchange splitting of the band structure.

Thin film phase diagram of iron nitrides grown by molecular beam epitaxy

Science.gov (United States)

Gölden, D.; Hildebrandt, E.; Alff, L.

2017-01-01

A low-temperature thin film phase diagram of the iron nitride system is established for the case of thin films grown by molecular beam epitaxy and nitrided by a nitrogen radical source. A fine-tuning of the nitridation conditions allows for growth of α ‧ -Fe8Nx with increasing c / a -ratio and magnetic anisotropy with increasing x until almost phase pure α ‧ -Fe8N1 thin films are obtained. A further increase of nitrogen content below the phase decomposition temperature of α ‧ -Fe8N (180 °C) leads to a mixture of several phases that is also affected by the choice of substrate material and symmetry. At higher temperatures (350 °C), phase pure γ ‧ -Fe4N is the most stable phase.

Enhanced antioxidation and microwave absorbing properties of SiO2-coated flaky carbonyl iron particles

Science.gov (United States)

Zhou, Yingying; Xie, Hui; Zhou, Wancheng; Ren, Zhaowen

2018-01-01

SiO2 was successfully coated on the surface of flaky carbonyl iron particles using a chemical bath deposition method in the presence of 3-aminopropyl triethoxysilane (APTES). The morphologies, composition, valence states of elements, as well as antioxidation and electromagnetic properties of the samples were characterized by scanning electron microscope (SEM), energy dispersive spectrometer (EDS), X-ray photoelectron spectroscopy (XPS), thermogravimetric (TG) and microwave network analyzer. TG curve shows the obvious weight gain of carbonyl iron was deferred to 360 °C after SiO2-coated, which can be ascribed to the exits of SiO2 overlayer. Compared with the raw carbonyl iron, SiO2-coated sample shows good wave absorption performance due to its impedance matching. The electromagnetic properties of raw and SiO2-coated carbonyl iron particles were characterized in X band before and after heat treatment at 250 °C for 10 h. It was established that SiO2-coated carbonyl iron demonstrate good thermal stability, indicating SiO2-coating is useful in the usage of microwave absorbers operating at temperature up to 250 °C.

An ultrathin polymer coating of carboxylate self-assembled monolayer adsorbed on passivated iron to prevent iron corrosion in 0.1 M Na2SO4

International Nuclear Information System (INIS)

Aramaki, Kunitsugu; Shimura, Tadashi

2010-01-01

For preparing an ultrathin two-dimensional polymer coating adsorbed on passivated iron, a 16-hydroxyhexadecanoate ion HO(CH 2 ) 15 CO 2 - self-assembled monolayer (SAM) was modified with 1,2-bis(triethoxysilyl)ethane (C 2 H 5 O) 3 Si(CH 2 ) 2 Si(OC 2 H 5 ) 3 and octadecyltriethoxysilane C 18 H 37 Si(OC 2 H 5 ) 3 . Protection of passivated iron against passive film breakdown and corrosion of iron was investigated by monitoring of the open-circuit potential and repeated polarization measurements in an aerated 0.1 M Na 2 SO 4 solution during immersion for many hours. The time required for passive film breakdown of the polymer-coated electrode was markedly higher in this solution than that of the passivated one, indicating protection of the passive film from breakdown by coverage with the polymer coating. The protective efficiencies of the passive film covered with the coating were extremely high, more than 99.9% in 0.1 M Na 2 SO 4 before the passive film was broken down, showing prominent cooperative suppression of iron corrosion in the solution by coverage with the passive film and polymer coating. The polymer-coated surface was characterized by contact angle measurement and electron-probe microanalysis (EPMA). Prevention of passive film breakdown and iron corrosion for the polymer-coated electrode healed in 0.1 M NaNO 3 was also examined in 0.1 M Na 2 SO 4 .

CEMS of nitride coatings in agressive environments

Science.gov (United States)

Hanžel, D.; Agudelo, A. C.; Gancedo, J. R.; Lakatos-Varsanyi, M.; Marco, J. F.

1998-12-01

The corrosion properties of single layered TiN and CrN films have been compared to bi-layered and multi-layered Ti/TiN films. XPS has showed that in humid SO2 atmosphere the best corrosion properties have been achieved by a multi-layered Ti/TiN coating. Cyclic voltammetry in acetate buffer has been applied to measure the porousity and corrosion resistance of coatings. The best results have been achieved by multi-layered Ti/TiN and CrN films. Conversion electron Mössbauer spectroscopy has been used to study the changes in the interface Fe/TiN during thermal treatment in UHV. It has been shown that the amount of iron nitrides in the interface increases with increasing temperature.

CEMS of nitride coatings in agressive environments

International Nuclear Information System (INIS)

Hanzel, D.; Agudelo, A.C.; Gancedo, J.R.; Lakatos-Varsanyi, M.; Marco, J.F.

1998-01-01

The corrosion properties of single layered TiN and CrN films have been compared to bi-layered and multi-layered Ti/TiN films. XPS has showed that in humid SO 2 atmosphere the best corrosion properties have been achieved by a multi-layered Ti/TiN coating. Cyclic voltammetry in acetate buffer has been applied to measure the porousity and corrosion resistance of coatings. The best results have been achieved by multi-layered Ti/TiN and CrN films. Conversion electron Moessbauer spectroscopy has been used to study the changes in the interface Fe/TiN during thermal treatment in UHV. It has been shown that the amount of iron nitrides in the interface increases with increasing temperature

CEMS of nitride coatings in agressive environments

Energy Technology Data Exchange (ETDEWEB)

Hanzel, D. [University of Ljubljana, J. Stefan Institute (Slovenia); Agudelo, A.C.; Gancedo, J.R. [Instituto de Quimica-Fisica ' Rocasolano' , CSIC (Spain); Lakatos-Varsanyi, M. [Eoetvoes University, Department of Physical Chemistry (Hungary); Marco, J.F. [Instituto de Quimica-Fisica ' Rocasolano' , CSIC (Spain)

1998-12-15

The corrosion properties of single layered TiN and CrN films have been compared to bi-layered and multi-layered Ti/TiN films. XPS has showed that in humid SO{sub 2} atmosphere the best corrosion properties have been achieved by a multi-layered Ti/TiN coating. Cyclic voltammetry in acetate buffer has been applied to measure the porousity and corrosion resistance of coatings. The best results have been achieved by multi-layered Ti/TiN and CrN films. Conversion electron Moessbauer spectroscopy has been used to study the changes in the interface Fe/TiN during thermal treatment in UHV. It has been shown that the amount of iron nitrides in the interface increases with increasing temperature.

Chemical vapor deposition of aluminide coatings on iron, nickel and superalloys

International Nuclear Information System (INIS)

John, John T.; De, P.K.; Dubey, Vivekanand; Srinivasa, Raman

2009-08-01

Aluminide coatings are a class of intermetallic coatings applied on nickel and cobalt base superalloys and steels to protect them from different forms of environmental degradation at high temperatures. In this report a CVD system that can produce the aluminide coatings on iron, nickel and nickel base alloys has been described and the result of chemical vapor deposition of aluminide coatings on iron specimens, their characterization, and property evaluation have been presented. The CVD system consists of an AlCl 3 bath, a stainless steel retort as a hot-wall reacto, cold traps and vacuum system. Aluminium chloride vapor was carried in a stream of hydrogen gas at a flow rate of 150 SCCM (standard cubic centimeter per minute) into the CVD reactor maintained in the temperature range of 1173 - 1373 K and at a pressure of 1.33 kPa (10 Torr). Aluminum deposition takes place from aluminium subchlorides produced by reaction between AlCl 3 and pure aluminum kept in the CVD reactor. The aluminum diffuses into the iron samples and iron aluminide phases are formed at the surface. The coatings were shining bright and showed good adherence to the substrate. The coatings consisted of FeAl phase over a wide range of experimental conditions. The growth kinetics of the coating followed a parabolic rate law and the mean activation energy was 212 ±16 kJ/mol. Optical microscopic studies on the transverse section of the coating showed that the aluminide coating on iron consisted of two layers. The top layer had a thickness in the range of 20-50 μm, and the under layer had thickness ranging from 35 to 250 μm depending on coating temperature in two hours. The thickness of the aluminide layer increased with coating duration and temperature. Electron microprobe studies (EPMA) showed that the aluminum concentration decreased steadily as distance from the surface increased. TEM studies showed that the outer most layer had a B2 order (of the FeAl phase), which extended even into the under

A study of DLC coatings for ironing of stainless steel

DEFF Research Database (Denmark)

Sulaiman, Mohd Hafis Bin; Christiansen, Peter; Bay, Niels Oluf

2017-01-01

severe lubrication conditions by adopting strip reduction testing to replicate industrial ironing production of deep drawn, stainless steel cans. Three DLC coatings are investigated; multi-layer, double layer and single layer. Experiments revealed that the double layer coating worked successful, i...

Electrochemical reduction of nitroaromatic compounds by single sheet iron oxide coated electrodes

Energy Technology Data Exchange (ETDEWEB)

Huang, Li-Zhi, E-mail: lizhi@plen.ku.dk [Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK–1871 Frederiksberg C (Denmark); Hansen, Hans Christian B. [Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, DK–1871 Frederiksberg C (Denmark); Bjerrum, Morten Jannik [Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK–2100 København Ø (Denmark)

2016-04-05

Highlights: • Composite layers of single sheet iron oxides were coated on indium tin oxide electrodes. • Single sheet iron oxide is an electro-catalyst for reduction of nitroaromatic compounds in aqueous solution. • The reduction is well explained by a diffusion layer model. • The charge properties of the nitrophenols have an important influence on reduction. • Low-cost iron oxide based materials are promising electro-catalyst for water treatment. - Abstract: Nitroaromatic compounds are substantial hazard to the environment and to the supply of clean drinking water. We report here the successful reduction of nitroaromatic compounds by use of iron oxide coated electrodes, and demonstrate that single sheet iron oxides formed from layered iron(II)-iron(III) hydroxides have unusual electrocatalytic reactivity. Electrodes were produced by coating of single sheet iron oxides on indium tin oxide electrodes. A reduction current density of 10 to 30 μA cm{sup −2} was observed in stirred aqueous solution at pH 7 with concentrations of 25 to 400 μM of the nitroaromatic compound at a potential of −0.7 V vs. SHE. Fast mass transfer favors the initial reduction of the nitroaromatic compound which is well explained by a diffusion layer model. Reduction was found to comprise two consecutive reactions: a fast four-electron first-order reduction of the nitro-group to the hydroxylamine-intermediate (rate constant = 0.28 h{sup −1}) followed by a slower two-electron zero-order reduction resulting in the final amino product (rate constant = 6.9 μM h{sup −1}). The zero-order of the latter reduction was attributed to saturation of the electrode surface with hydroxylamine-intermediates which have a more negative half-wave potential than the parent compound. For reduction of nitroaromatic compounds, the SSI electrode is found superior to metal electrodes due to low cost and high stability, and superior to carbon-based electrodes in terms of high coulombic efficiency and

In situ treatment of arsenic contaminated groundwater by aquifer iron coating: Experimental study

Energy Technology Data Exchange (ETDEWEB)

Xie, Xianjun, E-mail: xjxie@cug.edu.cn [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China); Wang, Yanxin, E-mail: yx.wang@cug.edu.cn [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China); Pi, Kunfu [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China); Liu, Chongxuan [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China); Pacific Northwest National Laboratory, Richland, WA 99354 (United States); Li, Junxia; Liu, Yaqing; Wang, Zhiqiang; Duan, Mengyu [State Key Laboratory of Biogeology and Environmental Geology, School of Environmental Studies, China University of Geosciences, 430074 Wuhan (China)

2015-09-15

In situ arsenic removal from groundwater by an aquifer iron coating method has great potential to be a cost effective and simple groundwater remediation technology, especially in rural and remote areas where groundwater is used as the main water source for drinking. The in situ arsenic removal technology was first optimized by simulating arsenic removal in various quartz sand columns under anoxic conditions. The effectiveness was then evaluated in an actual high-arsenic groundwater environment. The arsenic removal mechanism by the coated iron oxide/hydroxide was investigated under different conditions using scanning electron microscopy (SEM)/X-ray absorption spectroscopy, electron probe microanalysis, and Fourier transformation infrared spectroscopy. Aquifer iron coating method was developed via a 4-step alternating injection of oxidant, iron salt and oxygen-free water. A continuous injection of 5.0 mmol/L FeSO{sub 4} and 2.5 mmol/L NaClO for 96 h can form a uniform goethite coating on the surface of quartz sand without causing clogging. At a flow rate of 7.2 mL/min of the injection reagents, arsenic (as Na{sub 2}HAsO{sub 4}) and tracer fluorescein sodium to pass through the iron-coated quartz sand column were approximately at 126 and 7 column pore volumes, respectively. The retardation factor of arsenic was 23.0, and the adsorption capacity was 0.11 mol As per mol Fe. In situ arsenic removal from groundwater in an aquifer was achieved by simultaneous injections of As(V) and Fe(II) reagents. Arsenic fixation resulted from a process of adsorption/co-precipitation with fine goethite particles by way of bidentate binuclear complexes. Therefore, the study results indicate that the high arsenic removal efficiency of the in situ aquifer iron coating technology likely resulted from the expanded specific surface area of the small goethite particles, which enhanced arsenic sorption capability and/or from co-precipitation of arsenic on the surface of goethite particles

In situ treatment of arsenic contaminated groundwater by aquifer iron coating: Experimental study

International Nuclear Information System (INIS)

Xie, Xianjun; Wang, Yanxin; Pi, Kunfu; Liu, Chongxuan; Li, Junxia; Liu, Yaqing; Wang, Zhiqiang; Duan, Mengyu

2015-01-01

In situ arsenic removal from groundwater by an aquifer iron coating method has great potential to be a cost effective and simple groundwater remediation technology, especially in rural and remote areas where groundwater is used as the main water source for drinking. The in situ arsenic removal technology was first optimized by simulating arsenic removal in various quartz sand columns under anoxic conditions. The effectiveness was then evaluated in an actual high-arsenic groundwater environment. The arsenic removal mechanism by the coated iron oxide/hydroxide was investigated under different conditions using scanning electron microscopy (SEM)/X-ray absorption spectroscopy, electron probe microanalysis, and Fourier transformation infrared spectroscopy. Aquifer iron coating method was developed via a 4-step alternating injection of oxidant, iron salt and oxygen-free water. A continuous injection of 5.0 mmol/L FeSO 4 and 2.5 mmol/L NaClO for 96 h can form a uniform goethite coating on the surface of quartz sand without causing clogging. At a flow rate of 7.2 mL/min of the injection reagents, arsenic (as Na 2 HAsO 4 ) and tracer fluorescein sodium to pass through the iron-coated quartz sand column were approximately at 126 and 7 column pore volumes, respectively. The retardation factor of arsenic was 23.0, and the adsorption capacity was 0.11 mol As per mol Fe. In situ arsenic removal from groundwater in an aquifer was achieved by simultaneous injections of As(V) and Fe(II) reagents. Arsenic fixation resulted from a process of adsorption/co-precipitation with fine goethite particles by way of bidentate binuclear complexes. Therefore, the study results indicate that the high arsenic removal efficiency of the in situ aquifer iron coating technology likely resulted from the expanded specific surface area of the small goethite particles, which enhanced arsenic sorption capability and/or from co-precipitation of arsenic on the surface of goethite particles. - Highlights: �

In situ treatment of arsenic contaminated groundwater by aquifer iron coating: Experimental study.

Science.gov (United States)

Xie, Xianjun; Wang, Yanxin; Pi, Kunfu; Liu, Chongxuan; Li, Junxia; Liu, Yaqing; Wang, Zhiqiang; Duan, Mengyu

2015-09-15

In situ arsenic removal from groundwater by an aquifer iron coating method has great potential to be a cost effective and simple groundwater remediation technology, especially in rural and remote areas where groundwater is used as the main water source for drinking. The in situ arsenic removal technology was first optimized by simulating arsenic removal in various quartz sand columns under anoxic conditions. The effectiveness was then evaluated in an actual high-arsenic groundwater environment. The arsenic removal mechanism by the coated iron oxide/hydroxide was investigated under different conditions using scanning electron microscopy (SEM)/X-ray absorption spectroscopy, electron probe microanalysis, and Fourier transformation infrared spectroscopy. Aquifer iron coating method was developed via a 4-step alternating injection of oxidant, iron salt and oxygen-free water. A continuous injection of 5.0 mmol/L FeSO4 and 2.5 mmol/L NaClO for 96 h can form a uniform goethite coating on the surface of quartz sand without causing clogging. At a flow rate of 7.2 mL/min of the injection reagents, arsenic (as Na2HAsO4) and tracer fluorescein sodium to pass through the iron-coated quartz sand column were approximately at 126 and 7 column pore volumes, respectively. The retardation factor of arsenic was 23.0, and the adsorption capacity was 0.11 mol As per mol Fe. In situ arsenic removal from groundwater in an aquifer was achieved by simultaneous injections of As(V) and Fe(II) reagents. Arsenic fixation resulted from a process of adsorption/co-precipitation with fine goethite particles by way of bidentate binuclear complexes. Therefore, the study results indicate that the high arsenic removal efficiency of the in situ aquifer iron coating technology likely resulted from the expanded specific surface area of the small goethite particles, which enhanced arsenic sorption capability and/or from co-precipitation of arsenic on the surface of goethite particles. Copyright © 2015

A general strategy toward graphitized carbon coating on iron oxides as advanced anodes for lithium-ion batteries.

Science.gov (United States)

Ding, Chunyan; Zhou, Weiwei; Wang, Bin; Li, Xin; Wang, Dong; Zhang, Yong; Wen, Guangwu

2017-08-25

Integration of carbon materials with benign iron oxides is blazing a trail in constructing high-performance anodes for lithium-ion batteries (LIBs). In this paper, a unique general, simple, and controllable strategy is developed toward in situ uniform coating of iron oxide nanostructures with graphitized carbon (GrC) layers. The basic synthetic procedure only involves a simple dip-coating process for the loading of Ni-containing seeds and a subsequent Ni-catalyzed chemical vapor deposition (CVD) process for the growth of GrC layers. More importantly, the CVD treatment is conducted at a quite low temperature (450 °C) and with extremely facile liquid carbon sources consisting of ethylene glycol (EG) and ethanol (EA). The GrC content of the resulting hybrids can be controllably regulated by altering the amount of carbon sources. The electrochemical results reveal remarkable performance enhancements of iron oxide@GrC hybrids compared with pristine iron oxides in terms of high specific capacity, excellent rate and cycling performance. This can be attributed to the network-like GrC coating, which can improve not only the electronic conductivity but also the structural integrity of iron oxides. Moreover, the lithium storage performance of samples with different GrC contents is measured, manifesting that optimized electrochemical property can be achieved with appropriate carbon content. Additionally, the superiority of GrC coating is demonstrated by the advanced performance of iron oxide@GrC compared with its corresponding counterpart, i.e., iron oxides with amorphous carbon (AmC) coating. All these results indicate the as-proposed protocol of GrC coating may pave the way for iron oxides to be promising anodes for LIBs.

Laboratory Investigation of Complex Conductivity and Magnetic Susceptibility on Natural Iron Oxide Coated Sand

Science.gov (United States)

Wang, C.; Slater, L. D.; Day-Lewis, F. D.; Briggs, M. A.

2017-12-01

Redox reactions occurring at the oxic/anoxic interface where groundwater discharges to surface water commonly result in iron oxide deposition that coats sediment grains. With relatively large total surface area, these iron oxide coated sediments serve as a sink for sorption of dissolved contaminants, although this sink may be temporary if redox conditions fluctuate with varied flow conditions. Characterization of the distribution of iron oxides in streambed sediments could provide valuable understanding of biogeochemical reactions and the ability of a natural system to sorb contaminants. Towards developing a field methodology, we conducted laboratory spectral induced polarization (SIP) and magnetic susceptibility (MS) measurements on natural iron oxide coated sand (Fe-sand) with grain sizes ranging from 0.3 to 2.0 mm in order to assess the sensitivity of these measurements to iron oxides in sediments. The Fe-sand was also sorted by sieving into various grain sizes to study the impact of grain size on the polarization mechanisms. The unsorted Fe-sand saturated with 0.01 S/m NaCl solution exhibited a distinct phase response ( > 4 mrad) in the frequency range from 0.001 to 100 Hz whereas regular silica sand was characterized by a phase response less than 1 mrad under the same conditions. The presence of iron oxide substantially increased MS (3.08×10-3 SI) over that of regular sand ( Laboratory results demonstrated that SIP and MS may be well suited to mapping the distribution of iron oxides in streambed sediments associated with anoxic groundwater discharge.

Study of corrosion using long period fiber gratings coated with iron exposed to salty water

Science.gov (United States)

Coelho, L.; Santos, J. L.; Jorge, P. A. S.; de Almeida, J. M. M.

2017-04-01

A study of long period fiber gratings (LPFG) over coated with iron (Fe) and subjected to oxidation in water with different sodium chloride (NaCl) concentrations is presented. The formation of iron oxides and hydroxides was monitored in real time by following the features of the LPFG attenuation band. Preliminary results show that Fe coated LPFGs can be used as sensors for early warning of corrosion in offshore and in coastal projects where metal structures made of iron alloys are in contact with sea or brackish water.

Adsorption of arsenic(V) by iron-oxide-coated diatomite (IOCD).

Science.gov (United States)

Pan, Yi-Fong; Chiou, Cary T; Lin, Tsair-Fuh

2010-09-01

PURPOSES AND AIMS: Economically efficient methods for removing arsenic from the drinking water supply are urgently needed in many parts of the world. Iron oxides are known to have a strong affinity for arsenic in water. However, they are commonly present in the forms of fine powder or floc, which limits their utility in water treatment. In this study, a novel granular adsorbent, iron-oxide-coated diatomite (IOCD), was developed and examined for its adsorption of arsenic from water. An industrial-grade diatomite was used as the iron oxide support. The diatomite was first acidified and dried and then coated with iron oxide up to five times. The prepared IOCD samples were characterized for their morphology, composition, elemental content, and crystal properties by various instruments. Experiments of equilibrium and kinetic adsorption of As(V) on IOCD were conducted using 0.1- and 2-L polyethylene bottles, respectively, at different pH and temperatures. Iron oxide (alpha-Fe(2)O(3) hematite) coated onto diatomite greatly improves (by about 30 times) the adsorption of As(V) from water by IOCD as compared to using raw diatomite. This improvement was attributed to increases in both surface affinity and surface area of the IOCD. The surface area of IOCD increased to an optimal value. However, as the IOCD surface area (93 m(2)/g) was only 45% higher than that of raw diatomite (51 m(2)/g), the enhanced As(V) adsorption resulted primarily from the enhanced association of negatively charged As(V) ions with the partial positive surface charge of the iron oxide. The As(V) adsorption decreased when the solution pH was increased from 3.5 to 9.5, as expected from the partial charge interaction between As(V) and IOCD. The adsorption data at pH 5.5 and 7.5 could be well fitted to the Freundlich equation. A moderately high exothermic heat was observed for the As(V) adsorption, with the calculated molar isosteric heat ranging from -4 to -9 kcal/mol. The observed heats fall between those

Electroerosion formation and technology of cast iron coatings on aluminum alloys

Directory of Open Access Journals (Sweden)

Smolentsev Vladislav P.

2017-01-01

Full Text Available At present in the course of designing basic production parts and industrial equipment designers pay more and more attention to aluminum alloys having a number of properties compared favorably with other materials. In particular, technological aluminum tool electrodes without coating in the presence of products of processing with alkali in the composition of operation environment are being destroyed at the expense of intensified material dissolution. It is shown in the paper that the method offered by the authors and covered by the patents on cast iron coating of products made of aluminum alloys, allows obtaining on a product surface the layers with high adhesion durability ensuring a high protection against destruction in the friction units including operation in hostile environment. Thereupon, aluminum, as compared with iron-based alloys used at manufacturing technological equipment for electrical methods of processing, has a high electrical and thermal conduction, its application will allow achieving considerable energy-saving in the course of parts production. A procedure for the design of a technological process of qualitative cast iron coatings upon aluminum tool electrodes and parts of basic production used in different branches of mechanical engineering is developed.

Fabrication and properties of iron-based soft magnetic composites coated with parylene via chemical vapor deposition polymerization

International Nuclear Information System (INIS)

Wu, Shen; Sun, Aizhi; Lu, Zhenwen; Cheng, Chuan

2015-01-01

This paper focuses on novel iron-based soft magnetic composites synthesis utilizing low friction factor parylene C films to coat iron powder via chemical vapor deposition polymerization. The morphology, magnetic properties, density, and chemical stability of parylene insulated iron particles were investigated. The coated parylene insulating layer was characterized by scanning electron microscopy and energy dispersive X-ray spectroscopy. The thickness of parylene C film is averagely 300 nm according to the results of transmission electron microscopy. Parylene C film uniformly coated the powder surface resulting in reducing the permeability imaginary part, increasing electrical resistivity and increasing the operating frequency of the synthesized magnets. It was shown that the parylene C coated compacts exhibited noticeably higher density compared to the epoxy resin coated compacts at the same pressure, suppress at 800 MPa increased the density by 17.02%. The result of Tafel curves indicated that the resistance of the iron particles to corrosion by NaCl solution is obviously improved after being insulated with parylene C film. - Highlights: • Parylene C uniformly coated the powder, increased the operating frequency of SMCs. • Compared with epoxy coated, the density of SMCs increased by 17.02% at 800 MPa. • The resistance of the iron particles is obviously improved with parylene film insulated

N₂reduction and hydrogenation to ammonia by a molecular iron-potassium complex.

Science.gov (United States)

Rodriguez, Meghan M; Bill, Eckhard; Brennessel, William W; Holland, Patrick L

2011-11-11

The most common catalyst in the Haber-Bosch process for the hydrogenation of dinitrogen (N(2)) to ammonia (NH(3)) is an iron surface promoted with potassium cations (K(+)), but soluble iron complexes have neither reduced the N-N bond of N(2) to nitride (N(3-)) nor produced large amounts of NH(3) from N(2). We report a molecular iron complex that reacts with N(2) and a potassium reductant to give a complex with two nitrides, which are bound to iron and potassium cations. The product has a Fe(3)N(2) core, implying that three iron atoms cooperate to break the N-N triple bond through a six-electron reduction. The nitride complex reacts with acid and with H(2) to give substantial yields of N(2)-derived ammonia. These reactions, although not yet catalytic, give structural and spectroscopic insight into N(2) cleavage and N-H bond-forming reactions of iron.

Efficient internalization of silica-coated iron oxide nanoparticles of different sizes by primary human macrophages and dendritic cells

International Nuclear Information System (INIS)

Kunzmann, Andrea; Andersson, Britta; Vogt, Carmen; Feliu, Neus; Ye Fei; Gabrielsson, Susanne; Toprak, Muhammet S.; Buerki-Thurnherr, Tina; Laurent, Sophie; Vahter, Marie; Krug, Harald; Muhammed, Mamoun; Scheynius, Annika; Fadeel, Bengt

2011-01-01

Engineered nanoparticles are being considered for a wide range of biomedical applications, from magnetic resonance imaging to 'smart' drug delivery systems. The development of novel nanomaterials for biomedical applications must be accompanied by careful scrutiny of their biocompatibility. In this regard, particular attention should be paid to the possible interactions between nanoparticles and cells of the immune system, our primary defense system against foreign invasion. On the other hand, labeling of immune cells serves as an ideal tool for visualization, diagnosis or treatment of inflammatory processes, which requires the efficient internalization of the nanoparticles into the cells of interest. Here, we compare novel monodispersed silica-coated iron oxide nanoparticles with commercially available dextran-coated iron oxide nanoparticles. The silica-coated iron oxide nanoparticles displayed excellent magnetic properties. Furthermore, they were non-toxic to primary human monocyte-derived macrophages at all doses tested whereas dose-dependent toxicity of the smaller silica-coated nanoparticles (30 nm and 50 nm) was observed for primary monocyte-derived dendritic cells, but not for the similarly small dextran-coated iron oxide nanoparticles. No macrophage or dendritic cell secretion of pro-inflammatory cytokines was observed upon administration of nanoparticles. The silica-coated iron oxide nanoparticles were taken up to a significantly higher degree when compared to the dextran-coated nanoparticles, irrespective of size. Cellular internalization of the silica-coated nanoparticles was through an active, actin cytoskeleton-dependent process. We conclude that these novel silica-coated iron oxide nanoparticles are promising materials for medical imaging, cell tracking and other biomedical applications.

Characterization of Nitride Layers Formed by Nitrogen Ion Implantation into Surface Region of Iron

International Nuclear Information System (INIS)

Sudjatmoko; Subki, M. Iyos R.

2000-01-01

Ion implantation is a convenient means of modifying the physical and chemical properties of the near-surface region of materials. The nitrogen implantation into pure iron has been performed at room temperature with ion dose of 1.310 17 to 1.310 18 ions/cm 2 and ion energy of 20 to 100 keV. The optimum dose of nitrogen ions implanted into pure iron was around 2.2310 17 ions/cm 2 in order to get the maximum wear resistant. SEM micrographs and EDX show that the nitride layers were found on the surface of substrate. The nitrogen concentration profile was measured using EDX in combination with spot technique, and it can be shown that the depth profile of nitrogen implanted into substrate was nearly Gaussian. (author)

MR imaging of abscess by use of lipid-coated iron oxide particles

International Nuclear Information System (INIS)

Chan, T.W.; Eley, C.G.S.; Kressel, H.Y.

1990-01-01

The authors of this paper investigate the potential application of lipid-coated iron oxide particles as an MR contrast agent for imaging inflammatory process by using a rat subcutaneous abscess model induced by turpentine. Ten male Sprague-Dawley rats received subcutaneous injections of 0.1 mL of turpentine in the flank. At 24-36 hours later, the rats developed a subcutaneous abscess of 1-1.8 cm. An intravenous injection of lipid-coated iron oxide particles, Ferrosome (Vestar) at doses of 25, 40, 100, 200 μg/kg was administered. The animals were imaged at 12-24 hours later on a 1.5-T magnet using a 3-inch (7.62-cm) surface coil. Two animals were also imaged 5 days later. T1-weighted, T2-weighted, and multiplanar gradient-recalled (MPGR) sequences were obtained. The abscess was then excised and examined with routine H-E and iron staining

Study and modeling of the ironing process on a multi-layered polymer coated low-carbon steel

Science.gov (United States)

Selles Canto, Miguel Angel

The ironing process is the most crucial step in the manufacture of cans. Sheet steel covered by three polymer layers can be used as the starting material, but this coating must neither break nor fail in any manner in order to be considered as a viable and effective alternative to traditional practice. During ironing, the deformations are severe and high pressures exist at the tool-workpiece interface. Thickness reductions inherent in ironing require a large amount of surface generation. Deterioration of the coating in this delicate operation might enable direct contact of the stored food or drink with the metal. As can be appreciated, the key to the use of polymer-coated steel sheets in the manufacture of cans lies in the survival of these layers during the ironing process. Another important issue is the roughness of the newly-generated surface, because it should be possible to decorate the can without any difficulty. Changing the traditional manufacture of metallic containers such as cans and using this new coated material permits great reduction in environmental contaminants produced as a result of avoiding the formation of Volatile Organic Compounds (VOCs) during the manufacture of the polymer layers. This reduction is even greater because of not using additional lubricants due to the self-lubricanting property of the solid polymer coating layers during the drawing process. These objectives, together with the improvement of the mechanical characteristics and the adhesion of the painting or decorative priming, are realized by the use of the proposed material. In the existing bibliography about ironing processes on coated materials, some authors propose the use of the Upper Bound Theorem for modeling the material behavior. The present research shows for the first time the modeling of the ironing process on a three-layer polymer coated material. In addition, it takes into account the cases in which successful ironing is produced and those in which ones the ironing

Manganese and Iron Catalysts in Alkyd Paints and Coatings

Directory of Open Access Journals (Sweden)

Ronald Hage

2016-04-01

Full Text Available Many paint, ink and coating formulations contain alkyd-based resins which cure via autoxidation mechanisms. Whilst cobalt-soaps have been used for many decades, there is a continuing and accelerating desire by paint companies to develop alternatives for the cobalt soaps, due to likely classification as carcinogens under the REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals legislation. Alternative driers, for example manganese and iron soaps, have been applied for this purpose. However, relatively poor curing capabilities make it necessary to increase the level of metal salts to such a level that often coloring of the paint formulation occurs. More recent developments include the application of manganese and iron complexes with a variety of organic ligands. This review will discuss the chemistry of alkyd resin curing, the applications and reactions of cobalt-soaps as curing agents, and, subsequently, the paint drying aspects and mechanisms of (model alkyd curing using manganese and iron catalysts.

Preparation of nickel-coated titanium carbide particulates and their use in the production of reinforced iron matrix composites

International Nuclear Information System (INIS)

Yi, Danqing; Yu, Pengchao; Hu, Bin; Liu, Huiqun; Wang, Bin; Jiang, Yong

2013-01-01

Highlights: • Ni-coated TiC composite powders were prepared by electroless plating. • Iron-based composites reinforced by TiC particles was prepared by HIP. • Mechanical and wear properties were improved with the addition of Ni-coated TiC. • The nickel coating promotes the formation and growth of sintering neck. - Abstract: Ni-coated titanium carbide (TiC) composite powders were prepared by electroless plating (EP). Further, using hot isostatic pressing (HIP), iron matrix composites reinforced with 4 wt% Ni-coated TiC particulates with relative density close to 100% were prepared. The microstructure and phase composition of the Ni-coated powders and the composites were analyzed using X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The results showed that the TiC particles were distributed uniformly in the matrix and were free of segregation or coarsening. Compared to the TiC particles without Ni coating, the reinforced iron-based composites containing the Ni-coated particles showed higher relative densities and better mechanical properties. The density, hardness, tensile strength, and elongation were enhanced to 99.98%, 243 HV, 565 MPa, and 11.7%, respectively in composites containing Ni-coated TiC particles from 99.70%, 210 HV, 514 MPa, and 10.3%, respectively in composites that were prepared using particles without Ni coating. In addition, the mass losses in the composites containing the Ni-coated particles were reduced by 32–75% in the abrasive wear test with various vertical loads. We propose that the nickel coatings on the particulates had a beneficial effect on the microstructure and properties of the reinforced iron-based composites is due to promotion of neck formation and growth between TiC and iron powders during sintering, which enhanced the density of the sintered compact and the bonding strength between the TiC particles and the iron matrix

Iron binary and ternary coatings with molybdenum and tungsten

Energy Technology Data Exchange (ETDEWEB)

Yar-Mukhamedova, Gulmira, E-mail: gulmira-alma-ata@mail.ru [Institute Experimental and Theoretical Physics Al-Farabi Kazakh National University, 050038, Al-Farabi av., 71, Almaty (Kazakhstan); Ved, Maryna; Sakhnenko, Nikolay; Karakurkchi, Anna; Yermolenko, Iryna [National Technical University “Kharkov Polytechnic Institute”, Kharkov (Ukraine)

2016-10-15

Highlights: • High quality coatings of double Fe-Mo and ternary Fe-Mo-W electrolytic alloys can be produced both in a dc and a pulsed mode. • Application of unipolar pulsed current allows receiving an increased content of the alloying components and their more uniform distribution over the surface. • It is established that Fe-Mo and Fe-Mo-W coatings have an amorphous structure and exhibit improved corrosion resistance and microhardness as compared with the steel substrate due to the inclusion molybdenum and tungsten. - Abstract: Electrodeposition of Fe-Mo-W and Fe-Mo layers from a citrate solution containing iron(III) on steel and iron substrates is compared. The utilization of iron(III) compounds significantly improved the electrolyte stability eliminating side anodic redox reactions. The influence of concentration ratios and electrodeposition mode on quality, chemical composition, and functional properties of the alloys is determined. It has been found that alloys deposited in pulse mode have more uniform surface morphology and chemical composition and contain less impurities. Improvement in physical and mechanical properties as well as corrosion resistance of Fe-Mo and Fe-Mo-W deposits when compared with main alloy forming metals is driven by alloying components chemical passivity as well as by alloys amorphous structure. Indicated deposits can be considered promising materials in surface hardening technologies and repair of worn out items.

Clearance of iron oxide particles in rat liver: effect of hydrated particle size and coating material on liver metabolism.

Science.gov (United States)

Briley-Saebo, Karen C; Johansson, Lars O; Hustvedt, Svein Olaf; Haldorsen, Anita G; Bjørnerud, Atle; Fayad, Zahi A; Ahlstrom, Haakan K

2006-07-01

We sought to evaluate the effect of the particle size and coating material of various iron oxide preparations on the rate of rat liver clearance. The following iron oxide formulations were used in this study: dextran-coated ferumoxide (size = 97 nm) and ferumoxtran-10 (size = 21 nm), carboxydextran-coated SHU555A (size = 69 nm) and fractionated SHU555A (size = 12 nm), and oxidized-starch coated materials either unformulated NC100150 (size = 15 nm) or formulated NC100150 injection (size = 12 nm). All formulations were administered to 165 rats at 2 dose levels. Quantitative liver R2* values were obtained during a 63-day time period. The concentration of iron oxide particles in the liver was determined by relaxometry, and these values were used to calculate the particle half-lives in the liver. After the administration of a high dose of iron oxide, the half-life of iron oxide particles in rat liver was 8 days for dextran-coated materials, 10 days for carboxydextran materials, 14 days for unformulated oxidized-starch, and 29 days for formulated oxidized-starch. The results of the study indicate that materials with similar coating but different sizes exhibited similar rates of liver clearance. It was, therefore, concluded that the coating material significantly influences the rate of iron oxide clearance in rat liver.

Iron-based soft magnetic composites with Mn-Zn ferrite nanoparticles coating obtained by sol-gel method

Science.gov (United States)

Wu, Shen; Sun, Aizhi; Xu, Wenhuan; Zhang, Qian; Zhai, Fuqiang; Logan, Philip; Volinsky, Alex A.

2012-11-01

This paper focuses on iron-based soft magnetic composites which were synthesized by utilizing Mn-Zn ferrite nanoparticles to coat iron powder. The nanocrystalline iron powders, with an average particle diameter of 20 nm, were obtained via the sol-gel method. Scanning electron microscopy, energy dispersive X-ray spectroscopy and distribution maps show that the iron particle surface is covered with a thin layer of Mn-Zn ferrites. Mn-Zn ferrite uniformly coated the surface of the powder particles, resulting in a reduced imaginary permeability, increased electrical resistivity and a higher operating frequency of the synthesized magnets. Mn-Zn ferrite coated samples have higher permeability and lower magnetic loss when compared with the non-magnetic epoxy resin coated compacts. The real part of permeability increases by 33.5% when compared with the epoxy resin coated samples at 10 kHz. The effects of heat treatment temperature on crystalline phase formation and on the magnetic properties of the Mn-Zn ferrite were investigated via X-ray diffraction and a vibrating sample magnetometer. Ferrites decomposed to FeO and MnO after annealing above 400 °C in nitrogen; thus it is the optimum annealing temperature to attain the desired permeability.

N2 Reduction and Hydrogenation to Ammonia by a Molecular Iron-Potassium Complex

Science.gov (United States)

Rodriguez, Meghan M.; Bill, Eckhard; Brennessel, William W.; Holland, Patrick L.

2011-01-01

The most common catalyst in the Haber-Bosch process for the hydrogenation of dinitrogen (N2) to ammonia is an iron surface promoted with K+, but soluble iron complexes have neither reduced the N-N bond of N2 to nitride nor produced large amounts of NH3 from N2. We report a molecular iron complex that reacts with N2 and a potassium reductant to give a complex with two nitrides, which are bound to iron and potassium cations. The product has a Fe3N2 core, implying that three iron atoms cooperate to break the N-N triple bond through a six-electron reduction. The nitride complex reacts with acid and with H2 to give substantial yields of N2-derived ammonia. These reactions, though not yet catalytic, give structural and spectroscopic insight into N2 cleavage and N-H bond-forming reactions of iron. PMID:22076372

In situ functionalization and PEO coating of iron oxide nanocrystals using seeded emulsion polymerization.

Science.gov (United States)

Kloust, Hauke; Schmidtke, Christian; Feld, Artur; Schotten, Theo; Eggers, Robin; Fittschen, Ursula E A; Schulz, Florian; Pöselt, Elmar; Ostermann, Johannes; Bastús, Neus G; Weller, Horst

2013-04-16

Herein we demonstrate that seeded emulsion polymerization is a powerful tool to produce multiply functionalized PEO coated iron oxide nanocrystals. Advantageously, by simple addition of functional surfactants, functional monomers, or functional polymerizable linkers-solely or in combinations thereof-during the seeded emulsion polymerization process, a broad range of in situ functionalized polymer-coated iron oxide nanocrystals were obtained. This was demonstrated by purposeful modulation of the zeta potential of encapsulated iron oxide nanocrystals and conjugation of a dyestuff. Successful functionalization was unequivocally proven by TXRF. Furthermore, the spatial position of the functional groups can be controlled by choosing the appropriate spacers. In conclusion, this methodology is highly amenable for combinatorial strategies and will spur rapid expedited synthesis and purposeful optimization of a broad scope of nanocrystals.

Cell tagging with clinically approved iron oxides: feasibility and effect of lipofection, particle size, and surface coating on labeling efficiency.

Science.gov (United States)

Matuszewski, Lars; Persigehl, Thorsten; Wall, Alexander; Schwindt, Wolfram; Tombach, Bernd; Fobker, Manfred; Poremba, Christopher; Ebert, Wolfgang; Heindel, Walter; Bremer, Christoph

2005-04-01

To evaluate the effect of lipofection, particle size, and surface coating on labeling efficiency of mammalian cells with superparamagnetic iron oxides (SPIOs). Institutional Review Board approval was not required. Different human cell lines (lung and breast cancer, fibrosarcoma, leukocytes) were tagged by using carboxydextran-coated SPIOs of various hydrodynamic diameters (17-65 nm) and a dextran-coated iron oxide (150 nm). Cells were incubated with increasing concentrations of iron (0.01-1.00 mg of iron [Fe] per milliliter), including or excluding a transfection medium (TM). Cellular iron uptake was analyzed qualitatively at light and electron microscopy and was quantified at atomic emission spectroscopy. Cell visibility was assessed with gradient- and spin-echo magnetic resonance (MR) imaging. Effects of iron concentration in the medium and of lipofection on cellular SPIO uptake were analyzed with analysis of variance and two-tailed Student t test, respectively. Iron oxide uptake increased in a dose-dependent manner with higher iron concentrations in the medium. The TM significantly increased the iron load of cells (up to 2.6-fold, P .05). As few as 10 000 cells could be detected with clinically available MR techniques by using this approach. Lipofection-based cell tagging is a simple method for efficient cell labeling with clinically approved iron oxide-based contrast agents. Large particle size and carboxydextran coating are preferable for cell tagging with endocytosis- and lipofection-based methods. (c) RSNA, 2005.

Structural and optical properties of amorphous oxygenated iron boron nitride thin films produced by reactive co-sputtering

International Nuclear Information System (INIS)

Essafti, A.; Abouelaoualim, A.; Fierro, J.L.G.; Ech-chamikh, E.

2009-01-01

Amorphous oxygenated iron boron nitride (a-FeBN:O) thin films were prepared by reactive radio-frequency (RF) sputtering, from hexagonal boron nitride chips placed on iron target, under a total pressure of a gas mixture of argon and oxygen maintained at 1 Pa. The films were deposited onto silicon and glass substrates, at room temperature. The power of the generator RF was varied from 150 to 350 W. The chemical and structural analyses were investigated using X-ray photoelectron spectroscopy (XPS), energy dispersive of X-ray and X-ray reflectometry (XRR). The optical properties of the films were obtained from the optical transmittance and reflectance measurements in the ultraviolet-visible-near infrared wavelengths range. XPS reveals the presence of boron, nitrogen, iron and oxygen atoms and also the formation of different chemical bonds such as Fe-O, B-N, B-O and the ternary BNO phase. This latter phase is predominant in the deposited films as observed in the B 1s and N 1s core level spectra. As the RF power increases, the contribution of N-B bonds in the as-deposited films decreases. The XRR results show that the mass density of a-FeBN:O thin films increases from 2.6 to 4.12 g/cm 3 with increasing the RF power from 150 to 350 W. This behavior is more important for films deposited at RF power higher than 150 W, and has been associated with the enhancement of iron atoms in the film structure. The optical band gap decreases from 3.74 to 3.12 eV with increasing the RF power from 150 to 350 W.

Determination of corrosion potential of coated hollow spheres

International Nuclear Information System (INIS)

Fedorkova, Andrea; Orinakova, Renata; Orinak, Andrej; Dudrova, Eva; Kupkova, Miriam; Kalavsky, Frantisek

2008-01-01

Copper hollow spheres were created on porous iron particles by electro-less deposition. The consequent Ni plating was applied to improve the mechanical properties of copper hollow micro-particles. Corrosion properties of coated hollow spheres were investigated using potentiodynamic polarisation method in 1 mol dm -3 NaCl solution. Surface morphology and composition were studied by scanning electron microscopy (SEM), light microscopy (LM) and energy-dispersive X-ray spectroscopy (EDX). Original iron particles, uncoated copper spheres and iron particles coated with nickel were studied as the reference materials. The effect of particle composition, particularly Ni content on the corrosion potential value was investigated. The results indicated that an increase in the amount of Ni coating layer deteriorated corrosion resistivity of coated copper spheres. Amount of Ni coating layer depended on conditions of Ni electrolysis, mainly on electrolysis time and current intensity. Corrosion behaviour of sintered particles was also explored by potentiodynamic polarisation experiments for the sake of comparison. Formation of iron rich micro-volumes on the particle surface during sintering caused the corrosion potential shift towards more negative values. A detailed study of the morphological changes between non-sintered and sintered micro-particles provided explanation of differences in corrosion potential (E corr )

Accumulation of magnetic iron oxide nanoparticles coated with variably sized polyethylene glycol in murine tumors

DEFF Research Database (Denmark)

Larsen, Esben Kjær Unmack; Nielsen, Thomas; Wittenborn, Thomas

2012-01-01

Iron oxide nanoparticles have found widespread applications in different areas including cell separation, drug delivery and as contrast agents. Due to water insolubility and stability issues, nanoparticles utilized for biological applications require coatings such as the commonly employed...... polyethylene glycol (PEG). Despite its frequent use, the influence of PEG coatings on the physicochemical and biological properties of iron nanoparticles has hitherto not been studied in detail. To address this, we studied the effect of 333–20 000 Da PEG coatings that resulted in larger hydrodynamic size...

Identifying the optimal HVOF spray parameters to attain minimum porosity and maximum hardness in iron based amorphous metallic coatings

Directory of Open Access Journals (Sweden)

S. Vignesh

2017-04-01

Full Text Available Flow based Erosion – corrosion problems are very common in fluid handling equipments such as propellers, impellers, pumps in warships, submarine. Though there are many coating materials available to combat erosion–corrosion damage in the above components, iron based amorphous coatings are considered to be more effective to combat erosion–corrosion problems. High velocity oxy-fuel (HVOF spray process is considered to be a better process to coat the iron based amorphous powders. In this investigation, iron based amorphous metallic coating was developed on 316 stainless steel substrate using HVOF spray technique. Empirical relationships were developed to predict the porosity and micro hardness of iron based amorphous coating incorporating HVOF spray parameters such as oxygen flow rate, fuel flow rate, powder feed rate, carrier gas flow rate, and spray distance. Response surface methodology (RSM was used to identify the optimal HVOF spray parameters to attain coating with minimum porosity and maximum hardness.

Effect of Iron Oxides (Ordinary and Nano and Municipal Solid Waste Compost (MSWC Coated Sulfur on Wheat (Triticum aestivum L. Plant Iron Concentration and Growth

Directory of Open Access Journals (Sweden)

S Mazaherinia

2011-02-01

Full Text Available Abstract A greenhouse study was conducted to compare the effects of ordinary iron oxide (0.02-0.06 mm and nano iron oxide (25-250 nm and five levels of both iron oxides (0, 0.05, 0.1, 0.5, and 1.0 %w/w and two levels of sulfurous granular compost (MSW (0 and 2% w/w on plant height, spike length, grain weight per spike, total plant dry matter weight and thousands grain weight of wheat. The experimental factors were combined in factorial arrangement in a completely randomized design with 3 replications. Results showed that nano iron oxide was superior over ordinary iron oxide in all parameters studied. Fe concentration, spike length, plant height, grain weight per spike, total plant dry weight and thousands grain weight showed increasing trend per increase in both of iron oxides levels. Also, all parameters studied in sulfurous granular compost (MSW treatment were superior over granular compost without sulfurous (MSW. This increase in all parameters were significantly higher when urban solid waste compost coated with sulfur coupled with nano iron oxide compared to urban sulfurous granular compost (MSW along with ordinary iron oxide. Keywords: Sulfurous granular compost (MSW, Nano and ordinary iron oxides, Wheat

Ex vivo assessment of polyol coated-iron oxide nanoparticles for MRI diagnosis applications: toxicological and MRI contrast enhancement effects

Science.gov (United States)

Bomati-Miguel, Oscar; Miguel-Sancho, Nuria; Abasolo, Ibane; Candiota, Ana Paula; Roca, Alejandro G.; Acosta, Milena; Schwartz, Simó; Arus, Carles; Marquina, Clara; Martinez, Gema; Santamaria, Jesus

2014-03-01

Polyol synthesis is a promising method to obtain directly pharmaceutical grade colloidal dispersion of superparamagnetic iron oxide nanoparticles (SPIONs). Here, we study the biocompatibility and performance as T2-MRI contrast agents (CAs) of high quality magnetic colloidal dispersions (average hydrodynamic aggregate diameter of 16-27 nm) consisting of polyol-synthesized SPIONs (5 nm in mean particle size) coated with triethylene glycol (TEG) chains (TEG-SPIONs), which were subsequently functionalized to carboxyl-terminated meso-2-3-dimercaptosuccinic acid (DMSA) coated-iron oxide nanoparticles (DMSA-SPIONs). Standard MTT assays on HeLa, U87MG, and HepG2 cells revealed that colloidal dispersions of TEG-coated iron oxide nanoparticles did not induce any loss of cell viability after 3 days incubation with dose concentrations below 50 μg Fe/ml. However, after these nanoparticles were functionalized with DMSA molecules, an increase on their cytotoxicity was observed, so that particles bearing free terminal carboxyl groups on their surface were not cytotoxic only at low concentrations (MRI studies in mice indicated that both types of coated-iron oxide nanoparticles produced higher negative T2-MRI contrast enhancement than that measured for a similar commercial T2-MRI CAs consisting in dextran-coated ultra-small iron oxide nanoparticles (Ferumoxtran-10). In conclusion, the above attributes make both types of as synthesized coated-iron oxide nanoparticles, but especially DMSA-SPIONs, promising candidates as T2-MRI CAs for nanoparticle-enhanced MRI diagnosis applications.

Iron-based soft magnetic composites with Mn–Zn ferrite nanoparticles coating obtained by sol–gel method

International Nuclear Information System (INIS)

Wu, Shen; Sun, Aizhi; Xu, Wenhuan; Zhang, Qian; Zhai, Fuqiang; Logan, Philip; Volinsky, Alex A.

2012-01-01

This paper focuses on iron-based soft magnetic composites which were synthesized by utilizing Mn–Zn ferrite nanoparticles to coat iron powder. The nanocrystalline iron powders, with an average particle diameter of 20 nm, were obtained via the sol–gel method. Scanning electron microscopy, energy dispersive X-ray spectroscopy and distribution maps show that the iron particle surface is covered with a thin layer of Mn–Zn ferrites. Mn–Zn ferrite uniformly coated the surface of the powder particles, resulting in a reduced imaginary permeability, increased electrical resistivity and a higher operating frequency of the synthesized magnets. Mn–Zn ferrite coated samples have higher permeability and lower magnetic loss when compared with the non-magnetic epoxy resin coated compacts. The real part of permeability increases by 33.5% when compared with the epoxy resin coated samples at 10 kHz. The effects of heat treatment temperature on crystalline phase formation and on the magnetic properties of the Mn–Zn ferrite were investigated via X-ray diffraction and a vibrating sample magnetometer. Ferrites decomposed to FeO and MnO after annealing above 400 °C in nitrogen; thus it is the optimum annealing temperature to attain the desired permeability. - Highlights: ► Uniformly coated Mn–Zn ferrite powder increased the operating frequency of SMCs. ► Compared with epoxy coated, the permeability of SMCs increased by 33.5% at 10 kHz. ► 400 °C is the optimum annealing temperature to attain the desired permeability.

Phosphorus removal from aqueous solution using iron coated natural and engineered sorbents

International Nuclear Information System (INIS)

Boujelben, N.; Bouzid, J.; Elouear, Z.; Feki, M.; Jamoussi, F.; Montiel, A.

2008-01-01

New filtration materials covered with metallic oxides are good adsorbents for both cation and anion forms of pollutants. Sfax is one of the most important industrial towns in Tunisia. Its phosphate manufacture in particular is causing considerable amounts of water pollution. Therefore, there is a need to find out a new way of getting rid of this excessive phosphate from water. This work is aimed to examining the potential of three sorbent materials (synthetic iron oxide coated sand (SCS), naturally iron oxide coated sand (NCS) and iron oxide coated crushed brick (CB)) for removing phosphate ions from aqueous solutions. According to our literature survey CB was not used as adsorbent previously. Phosphate ions are used here as species model for the elimination of other similar pollutants (arsenates, antimonates). Optical microscope and scanning electron microscope (SEM) analyses were used to investigate the surface properties and morphology of the coated sorbents. Infra-red spectroscopy and X-ray diffraction techniques were also used to characterize the sorbent structures. Results showed that iron coated crushed brick possess more micro pores and a higher surface area owing to its clay nature. The comparative sorption of PO 4 3- from aqueous solutions by SCS, CB and NCS was investigated by batch experiments. The estimated optimum pH of phosphate ion retention for the considered sorbents was 5. The equilibrium data were analysed using the Langmuir and Freundlich isotherms. The sorption capacities of PO 4 3- at pH 5 were 1.5 mg/g for SCS, 1.8 mg/g for CB and 0.88 mg/g for NCS. The effect of temperature on sorption phenomenon was also investigated. The results indicated that adsorption is an endothermic process for phosphate ions removal. This study demonstrates that all the considered sorbents can be used as an alternative emerging technology for water treatment without any side effect or treatment process alteration

Low-temperature CVD of iron, cobalt, and nickel nitride thin films from bis[di(tert-butyl)amido]metal(II) precursors and ammonia

International Nuclear Information System (INIS)

Cloud, Andrew N.; Abelson, John R.; Davis, Luke M.; Girolami, Gregory S.

2014-01-01

Thin films of late transition metal nitrides (where the metal is iron, cobalt, or nickel) are grown by low-pressure metalorganic chemical vapor deposition from bis[di(tert-butyl)amido]metal(II) precursors and ammonia. These metal nitrides are known to have useful mechanical and magnetic properties, but there are few thin film growth techniques to produce them based on a single precursor family. The authors report the deposition of metal nitride thin films below 300 °C from three recently synthesized M[N(t-Bu) 2 ] 2 precursors, where M = Fe, Co, and Ni, with growth onset as low as room temperature. Metal-rich phases are obtained with constant nitrogen content from growth onset to 200 °C over a range of feedstock partial pressures. Carbon contamination in the films is minimal for iron and cobalt nitride, but similar to the nitrogen concentration for nickel nitride. X-ray photoelectron spectroscopy indicates that the incorporated nitrogen is present as metal nitride, even for films grown at the reaction onset temperature. Deposition rates of up to 18 nm/min are observed. The film morphologies, growth rates, and compositions are consistent with a gas-phase transamination reaction that produces precursor species with high sticking coefficients and low surface mobilities

Size-Dependent Accumulation of PEGylated Silane-Coated Magnetic Iron Oxide Nanoparticles in Murine Tumors

DEFF Research Database (Denmark)

Larsen, Esben Kjær Unmack; Nielsen, T.; Wittenborn, T.

2009-01-01

following intravenous injection. Biocompatible iron oxide MNPs coated with PEG were prepared by replacing oleic acid with a biocompatible and commercially available silane-PEG to provide an easy and effective method for chemical coating. The colloidal stable PEGylated MNPs were magnetically separated...... into two distinct size subpopulations of 20 and 40 nm mean diameters with increased phagocytic uptake observed for the 40 nm size range in vitro. MRI detection revealed greater iron accumulation in murine tumors for 40 nm nanoparticles after intravenous injection. The enhanced MRI contrast of the larger...

Fiber laser cladding of nickel-based alloy on cast iron

Energy Technology Data Exchange (ETDEWEB)

Arias-González, F., E-mail: felipeag@uvigo.es [Applied Physics Dpt., University of Vigo, EEI, Lagoas-Marcosende, Vigo E-36310 (Spain); Val, J. del [Applied Physics Dpt., University of Vigo, EEI, Lagoas-Marcosende, Vigo E-36310 (Spain); Comesaña, R. [Materials Engineering, Applied Mechanics and Construction Dpt., University of Vigo, EEI, Lagoas-Marcosende, Vigo E-36310 (Spain); Penide, J.; Lusquiños, F.; Quintero, F.; Riveiro, A.; Boutinguiza, M.; Pou, J. [Applied Physics Dpt., University of Vigo, EEI, Lagoas-Marcosende, Vigo E-36310 (Spain)

2016-06-30

Highlights: • Fiber laser cladding of Ni-based alloy on cast iron was experimentally studied. • Two different types of cast iron have been analyzed: gray and ductile cast iron. • Suitable processing parameters to generate a Ni-based coating were determined. • Dilution is higher in gray cast iron samples than in ductile cast iron. • Ni-based coating presents higher hardness than cast iron but similar Young's modulus. - Abstract: Gray cast iron is a ferrous alloy characterized by a carbon-rich phase in form of lamellar graphite in an iron matrix while ductile cast iron presents a carbon-rich phase in form of spheroidal graphite. Graphite presents a higher laser beam absorption than iron matrix and its morphology has also a strong influence on thermal conductivity of the material. The laser cladding process of cast iron is complicated by its heterogeneous microstructure which generates non-homogeneous thermal fields. In this research work, a comparison between different types of cast iron substrates (with different graphite morphology) has been carried out to analyze its impact on the process results. A fiber laser was used to generate a NiCrBSi coating over flat substrates of gray cast iron (EN-GJL-250) and nodular cast iron (EN-GJS-400-15). The relationship between processing parameters (laser irradiance and scanning speed) and geometry of a single laser track was examined. Moreover, microstructure and composition were studied by Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (EDS) and X-Ray Diffraction (XRD). The hardness and elastic modulus were analyzed by means of micro- and nanoindentation. A hardfacing coating was generated by fiber laser cladding. Suitable processing parameters to generate the Ni-based alloy coating were determined. For the same processing parameters, gray cast iron samples present higher dilution than cast iron samples. The elastic modulus is similar for the coating and the substrate, while the Ni

Growth and microstructure of iron nitride layers and pore formation in {epsilon}-Fe{sub 3}N

Energy Technology Data Exchange (ETDEWEB)

Middendorf, C.; Mader, W. [Univ. Bonn, Inst. fuer Anorganische Chemie, Bonn (Germany)

2003-03-01

Layers of {epsilon}-Fe{sub 3}N and {gamma}'-Fe{sub 4}N on ferrite were produced by nitriding iron single crystals or rolled sheets of iron in flowing ammonia at 520 C. The nitride layers were characterised using X-ray diffraction, light microscopy as well as scanning and transmission electron microscopy. The compound layer consists of {epsilon}-Fe{sub 3}N at the surface and of {gamma}'-Fe{sub 4}N facing the ferrite. After 4 h of nitriding, pores develop in the near surface region of {epsilon}-Fe{sub 3}N showing more or less open porosity. Growth of the entire compound layer as well as of the massive and the porous {epsilon}-Fe{sub 3}N sublayer is diffusion-controlled and follows a parabolic growth rate. The {gamma}'-Fe{sub 4}N layer is formed as a transition phase within a narrow interval of nitrogen activity, and it shows little growth in thickness. The transformation of {gamma}'-Fe{sub 4}N to {epsilon}-Fe{sub 3}N is topotactic, where the orientation of the closed-packed iron layers of the crystal structures is preserved. Determination of lattice plane spacings was possible by X-ray diffraction, and this was correlated to the nitrogen content of {epsilon}-Fe{sub 3}N. While the porous layer exhibits an enhanced nitrogen content corresponding to the chemical composition Fe{sub 3}N{sub 1.1}, the massive e Fe{sub 3}N layer corresponds to Fe{sub 3}N{sub 1.0}. The pore formation in {epsilon}-Fe{sub 3}N{sub 1.1} is concluded to be the result of excess nitrogen atoms on non-structural sites, which have a high mobility. Therefore, recombination of excess nitrogen to molecular N{sub 2} at lattice defects is preferred in {epsilon}-Fe{sub 3}N with high nitrogen content compared to stoichiometric {epsilon}-Fe{sub 3}N{sub 1.0} with nitrogen on only structural sites. (orig.)

Annealing effects on magnetic properties of silicone-coated iron-based soft magnetic composites

Science.gov (United States)

Wu, Shen; Sun, Aizhi; Zhai, Fuqiang; Wang, Jin; Zhang, Qian; Xu, Wenhuan; Logan, Philip; Volinsky, Alex A.

2012-03-01

This paper focuses on novel iron-based soft magnetic composites synthesis utilizing high thermal stability silicone resin to coat iron powder. The effect of an annealing treatment on the magnetic properties of synthesized magnets was investigated. The coated silicone insulating layer was characterized by scanning electron microscopy and energy dispersive X-ray spectroscopy. Silicone uniformly coated the powder surface, resulting in a reduction of the imaginary part of the permeability, thereby increasing the electrical resistivity and the operating frequency of the synthesized magnets. The annealing treatment increased the initial permeability, the maximum permeability, and the magnetic induction, and decreased the coercivity. Annealing at 580 °C increased the maximum permeability by 72.5%. The result of annealing at 580 °C shows that the ferromagnetic resonance frequency increased from 2 kHz for conventional epoxy resin coated samples to 80 kHz for the silicone resin insulated composites.

Microwave electromagnetic properties of carbonyl iron particles and Si/C/N nano-powder filled epoxy-silicone coating

International Nuclear Information System (INIS)

Qing Yuchang; Zhou Wancheng; Luo Fa; Zhu Dongmei

2010-01-01

The electromagnetic characteristics of carbonyl iron particles and Si/C/N nano-powder filled epoxy-silicone coatings were studied. The reflection loss of the coatings exceeds -10 dB at 8-18 GHz and -9 dB at 2-18 GHz when the coating thickness is 1 and 3 mm, respectively. The dielectric and magnetic absorbers filled coatings possess excellent microwave absorption, which could be attributed to the proper incorporate of the multi-polarization mechanisms as well as strong natural resonance. It is feasible to develop the thin and wideband microwave absorbing coatings using carbonyl iron particles and Si/C/N nano-powder.

Microwave electromagnetic properties of carbonyl iron particles and Si/C/N nano-powder filled epoxy-silicone coating

Science.gov (United States)

Qing, Yuchang; Zhou, Wancheng; Luo, Fa; Zhu, Dongmei

2010-02-01

The electromagnetic characteristics of carbonyl iron particles and Si/C/N nano-powder filled epoxy-silicone coatings were studied. The reflection loss of the coatings exceeds -10 dB at 8-18 GHz and -9 dB at 2-18 GHz when the coating thickness is 1 and 3 mm, respectively. The dielectric and magnetic absorbers filled coatings possess excellent microwave absorption, which could be attributed to the proper incorporate of the multi-polarization mechanisms as well as strong natural resonance. It is feasible to develop the thin and wideband microwave absorbing coatings using carbonyl iron particles and Si/C/N nano-powder.

Iron nanoparticles from blood coated with collagen as a matrix for ...

Indian Academy of Sciences (India)

A simple wet precipitation technique was used to prepare nanobiocomposite containing iron nanoparticles coated with collagen. This nanobiocomposite was used as matrix for the synthesis of nanohydroxyapatite. The physicochemical characteristic studies of the nanohydroxyapatite thus formed were carried out using ...

Structure and Corrosion Behavior of Arc-Sprayed Zn-Al Coatings on Ductile Iron Substrate

Science.gov (United States)

Bonabi, Salar Fatoureh; Ashrafizadeh, Fakhreddin; Sanati, Alireza; Nahvi, Saied Mehran

2018-02-01

In this research, four coatings including pure zinc, pure aluminum, a double-layered coating of zinc and aluminum, and a coating produced by simultaneous deposition of zinc and aluminum were deposited on a cast iron substrate using electric arc-spraying technique. The coatings were characterized by XRD, SEM and EDS map and spot analyses. Adhesion strength of the coatings was evaluated by three-point bending tests, where double-layered coating indicated the lowest bending angle among the specimens, with detection of cracks at the coating-substrate interface. Coatings produced by simultaneous deposition of zinc and aluminum possessed a relatively uniform distribution of both metals. In order to evaluate the corrosion behavior of the coatings, cyclic polarization and salt spray tests were conducted. Accordingly, pure aluminum coating showed susceptibility to pitting corrosion and other coatings underwent uniform corrosion. For double-layered coating, SEM micrographs revealed zinc corrosion products as flaky particles in the pores formed by pitting on the surface, an indication of penetration of corrosion products from the lower layer (zinc) to the top layer (aluminum). All coatings experienced higher negative corrosion potentials than the iron substrate, indicative of their sacrificial behavior.

Leachability of nitrided ilmenite in hydrochloric acid

OpenAIRE

Swanepoel, J.J.; van Vuuren, D.S.; Heydenrych, M.

2011-01-01

Titanium nitride in upgraded nitrided ilmenite (bulk of iron removed) can selectively be chlorinated to produce titanium tetrachloride. Except for iron, most other components present during this low temperature (ca. 200°C) chlorination reaction will not react with chlorine. It is therefore necessary to remove as much iron as possible from the nitrided ilmenite. Hydrochloric acid leaching is a possible process route to remove metallic iron from nitrided ilmenite without excessive dissolution o...

Surface functionalization of dopamine coated iron oxide nanoparticles for various surface functionalities

Energy Technology Data Exchange (ETDEWEB)

Sherwood, Jennifer; Xu, Yaolin; Lovas, Kira [Chemical and Biological Engineering, The University of Alabama, Tuscaloosa , AL 35487 (United States); Qin, Ying [Alabama Innovation and Mentoring of Entrepreneurs, The University of Alabama, Tuscaloosa, AL 35487 (United States); Bao, Yuping, E-mail: ybao@eng.ua.edu [Chemical and Biological Engineering, The University of Alabama, Tuscaloosa , AL 35487 (United States)

2017-04-01

We present effective conjugation of four small molecules (glutathione, cysteine, lysine, and Tris(hydroxymethyl)aminomethane) onto dopamine-coated iron oxide nanoparticles. Conjugation of these molecules could improve the surface functionality of nanoparticles for more neutral surface charge at physiological pH and potentially reduce non-specific adsorption of proteins to nanoparticles surfaces. The success of conjugation was evaluated with dynamic light scattering by measuring the surface charge changes and Fourier transform infrared spectroscopy for surface chemistry analysis. The stability of dopamine-coated nanoparticles and the ability of conjugated nanoparticles to reduce the formation of protein corona were evaluated by measuring the size and charge of the nanoparticles in biological medium. This facile conjugation method opens up possibilities for attaching various surface functionalities onto iron oxide nanoparticle surfaces for biomedical applications.

Surface functionalization of dopamine coated iron oxide nanoparticles for various surface functionalities

International Nuclear Information System (INIS)

Sherwood, Jennifer; Xu, Yaolin; Lovas, Kira; Qin, Ying; Bao, Yuping

2017-01-01

We present effective conjugation of four small molecules (glutathione, cysteine, lysine, and Tris(hydroxymethyl)aminomethane) onto dopamine-coated iron oxide nanoparticles. Conjugation of these molecules could improve the surface functionality of nanoparticles for more neutral surface charge at physiological pH and potentially reduce non-specific adsorption of proteins to nanoparticles surfaces. The success of conjugation was evaluated with dynamic light scattering by measuring the surface charge changes and Fourier transform infrared spectroscopy for surface chemistry analysis. The stability of dopamine-coated nanoparticles and the ability of conjugated nanoparticles to reduce the formation of protein corona were evaluated by measuring the size and charge of the nanoparticles in biological medium. This facile conjugation method opens up possibilities for attaching various surface functionalities onto iron oxide nanoparticle surfaces for biomedical applications.

Investigation on effect of iron and corundum content on corrosion resistance of the NiFe-Al2O3 coatings

International Nuclear Information System (INIS)

Starosta, R.; Zielinski, A.

1999-01-01

The alloy NiFe and composite NiFe-Al 2 O 3 coatings, obtained by electrodeposition on the base of cast iron, were investigated. The iron content in alloy coatings was dependent on iron content in galvanic bath, and was estimated by means of X-ray microanalysis at 18.5 wt. pct. and 41.2 wt. pct. No existence of ordered Ni 3 Fe phase was found by diffraction technique. Both potentiodynamic and impedance measurements disclosed that a presence of Al 2 O 3 or increasing iron content in the layer caused the decrease in corrosion resistance. (author)

Synthesis by reactive grinding of molybdenum iron bimetallic nitride; Sintesis por molienda reactiva del nitruro bimetalico Mo-Fe: Mo{sub 3}Fe{sub 3}N

Energy Technology Data Exchange (ETDEWEB)

Roldan, M. A.; Ortega, A.; Palencia, I.; Real, C.

2008-07-01

The transition metal nitride ternary show similar properties to the binary nitride and some times this behaviour are improved. In the present work, the molybdenum-iron nitride has been prepared by reactive grinding form the two metals under nitrogen atmosphere at a pressure of 11 bar. The characterization of the compounds is presented and it is also shown a study of the stability of the nitride under several atmospheres. (Author) 42 refs.

Enhancement in the Tribological and Mechanical Properties of Electroless Nickel-Nanodiamond Coatings Plated on Iron

Directory of Open Access Journals (Sweden)

Z. Karaguiozova

2017-12-01

Full Text Available A technology to improve the tribological and mechanical surface properties of iron alloys is developed based on the electroless nickel plating. The technology combines sol-gel and electroless deposition technique. Novel nanocomposite coatings are obtained consisting of Nickel-phosphorus-nanodiamond (Ni-P-ND. The ND sol is added directly to the electroless Ni-P solution. A suitable surfactant is added to achieve well-dispersed ND particles in the electroless solution to facilitate their embodiment and equal distribution in the coating. Substrates of steel 17CrNiMo6 and spheroidal graphite cast irons are used for the manufacture of the iron alloys specimens. The surface morphology and microstructure observation performed by scanning electron microscopy (SEM and optical metallography confirms the influence of ND particles on the coating structure. The structural phase investigation by X Ray analysis indicates a transformation of the amorphous phase to a crystalline one such as Ni, Ni3P after coatings' heat treatment. The microhardness investigation by Knoop Method and wear resistance measurement in accordance with the Polish Standard PN-83/H-04302 of Ni-P and Ni-P-ND composite coatings are evaluated and compared with each other. The increase in the value of hardness and wear resistance of Ni-P composite coatings in the presence of ND particles and after heat treatment is obtained.

Microstructure and wear behaviors of WC–12%Co coating deposited on ductile iron by electric contact surface strengthening

International Nuclear Information System (INIS)

Qi, Xiaoben; Zhu, Shigen; Ding, Hao; Zhu, Zhengkun; Han, Zhibing

2013-01-01

WC–12%Co powders deposited on ductile iron by electric contact strengthening were studied. This technology was based on the application of the contact resistance heating between the electrode and work piece to form a wear resistant layer on ductile iron. The microstructure, microhardness distribution, phase transformation and wear behaviors of the coating were investigated using optical microscope, scanning electron microscope, Vickers hardness (HV 0.5 ), X-ray diffraction, rolling contact wear tests. The results showed that the WC–12%Co coating by electric contact strengthening was metallurgically bonded to the ductile iron. Additionally, the effect of experimental parameters on microhardness and wear resistance of coatings were studied using orthogonal experiment. The results showed that compared with (A) electric current and (B) rotating speed, (C) contact force displays the most significant effect on microhardness and wear resistance of coatings. The coatings produced at A = 19 kA, B = 0.3 r/min and C = 700 N possessed highest microhardness of 1073 HV 0.5 and wear resistance.

Dinitrogen binding and cleavage by multinuclear iron complexes.

Science.gov (United States)

McWilliams, Sean F; Holland, Patrick L

2015-07-21

The iron-molybdenum cofactor of nitrogenase has unprecedented coordination chemistry, including a high-spin iron cluster called the iron-molybdenum cofactor (FeMoco). Thus, understanding the mechanism of nitrogenase challenges coordination chemists to understand the fundamental N2 chemistry of high-spin iron sites. This Account summarizes a series of studies in which we have synthesized a number of new compounds with multiple iron atoms, characterized them using crystallography and spectroscopy, and studied their reactions in detail. These studies show that formally iron(I) and iron(0) complexes with three- and four-coordinate metal atoms have the ability to weaken and break the triple bond of N2. These reactions occur at or below room temperature, indicating that they are kinetically facile. This in turn implies that iron sites in the FeMoco are chemically reasonable locations for N2 binding and reduction. The careful evaluation of these compounds and their reaction pathways has taught important lessons about what characteristics make iron more effective for N2 activation. Cooperation of two iron atoms can lengthen and weaken the N-N bond, while three working together enables iron atoms to completely cleave the N-N bond to nitrides. Alkali metals (typically introduced into the reaction as part of the reducing agent) are thermodynamically useful because the alkali metal cations stabilize highly reduced complexes, pull electron density into the N2 unit, and make reduced nitride products more stable. Alkali metals can also play a kinetic role, because cation-π interactions with the supporting ligands can hold iron atoms near enough to one another to facilitate the cooperation of multiple iron atoms. Many of these principles may also be relevant to the iron-catalyzed Haber-Bosch process, at which collections of iron atoms (often promoted by the addition of alkali metals) break the N-N bond of N2. The results of these studies teach more general lessons as well. They

Generation of drugs coated iron nanoparticles through high energy ball milling

Energy Technology Data Exchange (ETDEWEB)

Radhika Devi, A.; Murty, B. S. [Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai 600036 (India); Chelvane, J. A. [Defence Metallurgical Research Laboratory, Hyderabad 500058 (India); Prabhakar, P. K.; Padma Priya, P. V.; Doble, Mukesh [Department of Biotechnology, Indian Institute of Technology Madras, Chennai 600036 (India)

2014-03-28

The iron nanoparticles coated with oleic acid and drugs such as folic acid/Amoxicillin were synthesized by high energy ball milling and characterized by X-ray diffraction, Transmission electron microscope, zeta potential, dynamic light scattering, Fourier Transform Infra red (FT-IR) measurements, and thermo gravimetric analysis (TGA). FT-IR and TGA measurements show good adsorption of drugs on oleic acid coated nanoparticles. Magnetic measurements indicate that saturation magnetization is larger for amoxicillin coated particles compared to folic acid coated particles. The biocompatibility of the magnetic nanoparticles prepared was evaluated by in vitro cytotoxicity assay using L929 cells as model cells.

A study of DLC coatings for ironing of stainless steel

Science.gov (United States)

Sulaiman, M. H.; Christiansen, P.; Bay, N.

2017-09-01

Stamping of sheet metal components without lubrication or using minimum amount of hazard free lubricant is a possible solution to diminish health hazards to personnel and environmental impact and to reduce production costs. This paper studies the application of diamond-like coating (DLC) under severe lubrication conditions by adopting strip reduction testing to replicate industrial ironing production of deep drawn, stainless steel cans. Three DLC coatings are investigated; multi-layer, double layer and single layer. Experiments revealed that the double layer coating worked successful, i.e. with no sign of galling using no lubrication even at elevated tool temperature, while the other two coatings peeled off and resulted in severe galling unless lubrication was applied.

The formation of magnetic carboxymethyl-dextrane-coated iron-oxide nanoparticles using precipitation from an aqueous solution

International Nuclear Information System (INIS)

Makovec, Darko; Gyergyek, Sašo; Primc, Darinka; Plantan, Ivan

2015-01-01

The formation of spinel iron-oxide nanoparticles during the co-precipitation of Fe 3+ /Fe 2+ ions from an aqueous solution in the presence of carboxymethyldextrane (CMD) was studied. To follow the formation of the nanoparticles, a mixture of the Fe ions, CMD and ammonia was heated to different temperatures, while the samples were taken, quenched in liquid nitrogen, freeze-dried and characterized using transmission electron microscopy (TEM), X-ray diffractometry (XRD) and magnetometry. The CMD plays a role in the reactions of the Fe ions' precipitation by partially immobilizing the Fe 3+ ions into a complex. At room temperature, the amorphous material is precipitated. Then, above approximately 30 °C, the spinel nanoparticles form inside the amorphous matrix, and at approximately 40 °C the matrix decomposes into the suspension of carboxymethyl-dextrane-coated iron-oxide nanoparticles. The CMD bonded to the nanoparticles' surfaces hinders the mass transport and thus prevents their growth. - Highlights: • The carboxymethyl-dextrane coated iron-oxide nanoparticles were synthesized. • The carboxymethyl-dextrane significantly modifies formation of the spinel nanoparticles. • The spinel nanoparticles are formed inside the amorphous matrix. • At approximately 40 °C the matrix decomposes into the suspension of carboxymethyl-dextrane-coated iron-oxide nanoparticles

The formation of magnetic carboxymethyl-dextrane-coated iron-oxide nanoparticles using precipitation from an aqueous solution

Energy Technology Data Exchange (ETDEWEB)

Makovec, Darko [Department for Materials Synthesis, Jožef Stefan Institute, Jamova ulica 39, SI-1000 Ljubljana (Slovenia); Gyergyek, Sašo, E-mail: saso.gyergyek@ijs.si [Department for Materials Synthesis, Jožef Stefan Institute, Jamova ulica 39, SI-1000 Ljubljana (Slovenia); Primc, Darinka [Department for Materials Synthesis, Jožef Stefan Institute, Jamova ulica 39, SI-1000 Ljubljana (Slovenia); Plantan, Ivan [Lek Pharmaceuticals d.d., Mengeš (Slovenia)

2015-03-01

The formation of spinel iron-oxide nanoparticles during the co-precipitation of Fe{sup 3+}/Fe{sup 2+} ions from an aqueous solution in the presence of carboxymethyldextrane (CMD) was studied. To follow the formation of the nanoparticles, a mixture of the Fe ions, CMD and ammonia was heated to different temperatures, while the samples were taken, quenched in liquid nitrogen, freeze-dried and characterized using transmission electron microscopy (TEM), X-ray diffractometry (XRD) and magnetometry. The CMD plays a role in the reactions of the Fe ions' precipitation by partially immobilizing the Fe{sup 3+} ions into a complex. At room temperature, the amorphous material is precipitated. Then, above approximately 30 °C, the spinel nanoparticles form inside the amorphous matrix, and at approximately 40 °C the matrix decomposes into the suspension of carboxymethyl-dextrane-coated iron-oxide nanoparticles. The CMD bonded to the nanoparticles' surfaces hinders the mass transport and thus prevents their growth. - Highlights: • The carboxymethyl-dextrane coated iron-oxide nanoparticles were synthesized. • The carboxymethyl-dextrane significantly modifies formation of the spinel nanoparticles. • The spinel nanoparticles are formed inside the amorphous matrix. • At approximately 40 °C the matrix decomposes into the suspension of carboxymethyl-dextrane-coated iron-oxide nanoparticles.

Effect of coating thickness of iron oxide nanoparticles on their relaxivity in the MRI

Directory of Open Access Journals (Sweden)

Farzaneh Hajesmaeelzadeh

2016-02-01

Full Text Available Objective(s:Iron oxide nanoparticles have found prevalent applications in various fields including drug delivery, cell separation and as contrast agents. Super paramagnetic iron oxide (SPIO nanoparticles allow researchers and clinicians to enhance the tissue contrast of an area of interest by increasing the relaxation rate of water. In this study, we evaluate the dependency of hydrodynamic size of iron oxide nanoparticles coated with Polyethylene  glycol (PEG on their relativities with 3 Tesla clinical MRI. Materials and Methods: We used three groups of nanoparticles with nominal sizes 20, 50 and 100 nm with a core size of 8.86 nm, 8.69 nm and 10.4 nm that they were covered with PEG 300 and 600 Da. A clinical magnetic resonance scanner determines the T1 and T2 relaxation times for various concentrations of PEG-coated nanoparticles. Results: The size measurement by photon correlation spectroscopy showed the hydrodynamic sizes of MNPs with nominal 20, 50 and 100 nm with 70, 82 and 116 nm for particles with PEG 600 coating and 74, 93 and 100 nm for  particles with PEG 300 coating, respectively. We foud that the relaxivity decreased with increasing overall particle size (via coating thickness. Magnetic resonance imaging showed that by increasing the size of the nanoparticles, r2/r1 increases linearly. Conclusion: According to the data obtained from this study it can be concluded that increments in coating thickness have more influence on relaxivities compared to the changes in core size of magnetic nanoparticles.

A study on the corrosion and erosion behavior of electroless nickel and TiAlN/ZrN duplex coatings on ductile iron

Energy Technology Data Exchange (ETDEWEB)

Lin, Chung-Kwei [School of Dental Technology, Taipei Medical University, Taipei 110, Taiwan (China); Hsu, Cheng-Hsun, E-mail: chhsu@ttu.edu.tw [Department of Materials Engineering, Tatung University, Taipei 104, Taiwan (China); College of Oral Medicine, Taipei Medical University, Taipei 110, Taiwan (China); Cheng, Yin-Hwa [Department of Materials Engineering, Tatung University, Taipei 104, Taiwan (China); Ou, Keng-Liang [College of Oral Medicine, Taipei Medical University, Taipei 110, Taiwan (China); Department of Mechanical Engineering, National Central University, Taoyuan 320, Taiwan (China); Lee, Sheng-Long [Research Center for Biomedical Devices and Prototyping Production, Taipei Medical University, Taipei 110, Taiwan (China)

2015-01-01

Highlights: • Electroless nickel was used as an interlayer for TiAlZrN-coated ductile iron. • The duplex coatings evidently improved corrosion resistance of ductile iron. • The duplex coated ductile iron showed a good erosion resistance. - Abstract: This study utilized electroless nickel (EN) and cathodic arc evaporation (CAE) technologies to deposit protective coatings onto ductile iron. Polarization corrosion tests were performed in 3.5 wt.% sodium chloride, and also erosion tests were carried out by using Al{sub 2}O{sub 3} particles (∼177 μm in size and Mohr 7 scale) of about 5 g. Surface morphologies of the corroded and eroded specimens were observed separately. To further understand the coating effects on both the corrosive and erosive behavior of ductile iron, coating structure, morphology, and adhesion were analyzed using X-ray diffractormeter, scanning electron microscopy, and Rockwell-C indenter, respectively. The results showed that the EN exhibited an amorphous structure while the CAE-TiAlN/ZrN coating was a multilayered nanocrystalline. When the TiAlN/ZrN coated specimen with EN interlayer could effectively increase the adhesion strength between the CAE coating and substrate. Consequently, the combination of TiAlN/ZrN and EN delivered a better performance than did the monolithic EN or TiAlN/ZrN for both corrosion and erosion protection.

A study on the corrosion and erosion behavior of electroless nickel and TiAlN/ZrN duplex coatings on ductile iron

International Nuclear Information System (INIS)

Lin, Chung-Kwei; Hsu, Cheng-Hsun; Cheng, Yin-Hwa; Ou, Keng-Liang; Lee, Sheng-Long

2015-01-01

Highlights: • Electroless nickel was used as an interlayer for TiAlZrN-coated ductile iron. • The duplex coatings evidently improved corrosion resistance of ductile iron. • The duplex coated ductile iron showed a good erosion resistance. - Abstract: This study utilized electroless nickel (EN) and cathodic arc evaporation (CAE) technologies to deposit protective coatings onto ductile iron. Polarization corrosion tests were performed in 3.5 wt.% sodium chloride, and also erosion tests were carried out by using Al 2 O 3 particles (∼177 μm in size and Mohr 7 scale) of about 5 g. Surface morphologies of the corroded and eroded specimens were observed separately. To further understand the coating effects on both the corrosive and erosive behavior of ductile iron, coating structure, morphology, and adhesion were analyzed using X-ray diffractormeter, scanning electron microscopy, and Rockwell-C indenter, respectively. The results showed that the EN exhibited an amorphous structure while the CAE-TiAlN/ZrN coating was a multilayered nanocrystalline. When the TiAlN/ZrN coated specimen with EN interlayer could effectively increase the adhesion strength between the CAE coating and substrate. Consequently, the combination of TiAlN/ZrN and EN delivered a better performance than did the monolithic EN or TiAlN/ZrN for both corrosion and erosion protection

SYNTHESIS AND CORROSION PROTECTION BEHAVIOR OF EPOXYTiO2-MICACEOUS IRON OXIDE NANO - COMPOSITE COATING ON St-37

Directory of Open Access Journals (Sweden)

M. R. Khorram

2016-03-01

Full Text Available The micro layers micaceous iron oxide and nano-TiO 2 were incorporated into the epoxy resin by mechanical mixing and sonication process. Optical micrographs showed that the number and diameter size of nanoparticle agglomerates were decreased by sonication. The structure and composition of the nanocomposite was determined using transmission electron microscopy which showed the presence of dispersed nano-TiO 2 in the polymer matrix. The anticorrosive properties of the synthesized nano-composites coating were investigated using salt spray, electrochemical impedance spectroscopy and polarization measurement. The EIS results showed that coating resistance increased by addition of micaceous iron oxide micro layers and nano-TiO 2 particles to the epoxy coatings. It was observed that higher corrosion protection of nanocomposite coatings obtained by the addition of 3 %wt micaceous iron oxide and 4%wt nano-TiO 2 into epoxy resin.

PAMAM dendrimer-coated iron oxide nanoparticles: synthesis and characterization of different generations

International Nuclear Information System (INIS)

Khodadust, Rouhollah; Unsoy, Gozde; Yalcın, Serap; Gunduz, Gungor; Gunduz, Ufuk

2013-01-01

This study focuses on the synthesis and characterization of different generations (G 0 –G 7 ) of polyamidoamine (PAMAM) dendrimer-coated magnetic nanoparticles (DcMNPs). In this study, superparamagnetic iron oxide nanoparticles were synthesized by co-precipitation method. The synthesized nanoparticles were modified with aminopropyltrimethoxysilane for dendrimer coating. Aminosilane-modified MNPs were coated with PAMAM dendrimer. The characterization of synthesized nanoparticles was performed by X-ray diffraction, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering, and vibrating sample magnetometry (VSM) analyses. TEM images demonstrated that the DcMNPs have monodisperse size distribution with an average particle diameter of 16 ± 5 nm. DcMNPs were found to be superparamagnetic through VSM analysis. The synthesis, aminosilane modification, and dendrimer coating of iron oxide nanoparticles were validated by FTIR and XPS analyses. Cellular internalization of nanoparticles was studied by inverted light scattering microscopy, and cytotoxicity was determined by XTT analysis. Results demonstrated that the synthesized DcMNPs, with their functional groups, symmetry perfection, size distribution, improved magnetic properties, and nontoxic characteristics could be suitable nanocarriers for targeted cancer therapy upon loading with various anticancer agents.

Preparation of alginate coated chitosan microparticles for vaccine delivery

Directory of Open Access Journals (Sweden)

Wei YuQuan

2008-11-01

Full Text Available Abstract Background Absorption of antigens onto chitosan microparticles via electrostatic interaction is a common and relatively mild process suitable for mucosal vaccine. In order to increase the stability of antigens and prevent an immediate desorption of antigens from chitosan carriers in gastrointestinal tract, coating onto BSA loaded chitosan microparticles with sodium alginate was performed by layer-by-layer technology to meet the requirement of mucosal vaccine. Results The prepared alginate coated BSA loaded chitosan microparticles had loading efficiency (LE of 60% and loading capacity (LC of 6% with mean diameter of about 1 μm. When the weight ratio of alginate/chitosan microparticles was greater than 2, the stable system could be obtained. The rapid charge inversion of BSA loaded chitosan microparticles (from +27 mv to -27.8 mv was observed during the coating procedure which indicated the presence of alginate layer on the chitosan microparticles surfaces. According to the results obtained by scanning electron microscopy (SEM, the core-shell structure of BSA loaded chitosan microparticles was observed. Meanwhile, in vitro release study indicated that the initial burst release of BSA from alginate coated chitosan microparticles was lower than that observed from uncoated chitosan microparticles (40% in 8 h vs. about 84% in 0.5 h. SDS-polyacrylamide gel electrophoresis (SDS-PAGE assay showed that alginate coating onto chitosan microparticles could effectively protect the BSA from degradation or hydrolysis in acidic condition for at least 2 h. The structural integrity of alginate modified chitosan microparticles incubated in PBS for 24 h was investigated by FTIR. Conclusion The prepared alginate coated chitosan microparticles, with mean diameter of about 1 μm, was suitable for oral mucosal vaccine. Moreover, alginate coating onto the surface of chitosan microparticles could modulate the release behavior of BSA from alginate coated chitosan

Preparation of carbon-encapsulated iron nanoparticles in high yield by DC arc discharge and their characterization

International Nuclear Information System (INIS)

Zhang, Fan; Cui, Lan; Lin, Kui; Jin, Feng-min; Wang, Bin; Shi, Shu-xiu; Yang, De-an; Wang, Hui; He, Fei; Chen, Xiao-ping; Cui, Shen

2013-01-01

Highlights: ► CEINPs with core–shell structure and high Fe content were prepared in high yield by DC arc discharge. ► The anode II with a mass ratio of total iron to carbon 8:1 was used in DC arc discharge. ► The possible process of formation of CEINPs is briefly discussed. ► The uniformity of composition of anode is very important for the formation of CEINPs. ► The MEF and MMF of iron element may also play an important role in the formation of CEINPs. -- Abstract: Carbon-encapsulated iron nanoparticles (CEINPs) were prepared by DC arc discharge under nitrogen atmosphere of high temperature. The products were characterized by transmission electron microscope (TEM), high-resolution transmission electron microscope (HRTEM), X-ray diffractometer (XRD), energy dispersive X-ray (EDX) spectroscope, and X-ray photoelectron spectroscope (XPS), and their magnetic properties were measured by physical property measurement system (PPMS). The product B I , obtained from the anode I, contains the nanoparticles of iron and iron carbide, and carbon coating with imperfect and disordered layer structure. The product B II , obtained from the anode II, mainly consists of CEINPs, whose cores mainly consist of iron and iron carbide and shells contain about 3–7 graphitic layers. The iron contents in the products B I and B II are 44.8 and 82.6 wt.%, respectively. The products B I and B II have similar phase composition which includes carbon, iron, iron carbide, ferrous and ferric oxide, iron nitride, and carbon nitride. The saturation magnetization (Ms) of the products B I and B II are 29.35 and 88.66 emu/g and their coercivity (Hc) are 220 and 240 Oe, respectively. The total yields of all the products formed in the arc discharge chamber from anodes I and II, except for the cylinder-shaped deposits formed on the top of the cathode, are 25.8 and 22.3 wt.%, respectively. The possible process of formation of CEINPs is briefly discussed on the foundation of our results and other

Evaluation of Iron and Manganese-Coated Pumice Application for the Removal of as(v from Aqueous Solutions

Directory of Open Access Journals (Sweden)

Leila Babaie Far

2012-12-01

Full Text Available Arsenic contamination of water has been recognized as a serious environmental issue and there are reports on its epidemiological problems to human health. The objective of this study was to evaluate the performances of iron-coated pumice and manganese-coated pumice as the adsorbents for removing arsenate from aqueous solutions. The effect of various parameters such as adsorbent dose, contact time, pH and initial concentration on removal efficiency of arsenate were evaluated in batch mode. The data obtained from the kinetic studies were analyzed using kinetic models of pseudo-first-order and pseudo-second-order. In addition, two isotherm models of Freundlich and Langmuir were used to fit the experimental data. The results showed that the optimum dosage of iron-coated pumice and manganese-coated pumice for arsenate removal were 40 and 80 g/L whereas the adsorption process reached equilibrium after 80 and 100 min, respectively. The maximum removal efficiency of arsenate using the two adsorbents were both recorded in pH=3 as the removal efficiency gradually declinedfollowing every increase in pH values of the solution. Iron-coated pumice also showed to have high removal efficiency when the initial concentration of arsenate was high while the low concentration of arsenate was efficiently removed by manganese-coated pumice. Moreover, it was depicted that the adsorption kinetics by bothadsorbents followed pseudo-second order equation and the uptake data of arsenate were well fitted with Langmuir isotherm model. Therefore, it could be concluded that iron and manganese-coated pumice could beconsidered as suitable adsorbents for arsenate removal from aqueous solutions.

Toxicity assessment of silica coated iron oxide nanoparticles and biocompatibility improvement by surface engineering.

Directory of Open Access Journals (Sweden)

Maria Ada Malvindi

Full Text Available We have studied in vitro toxicity of iron oxide nanoparticles (NPs coated with a thin silica shell (Fe3O4/SiO2 NPs on A549 and HeLa cells. We compared bare and surface passivated Fe3O4/SiO2 NPs to evaluate the effects of the coating on the particle stability and toxicity. NPs cytotoxicity was investigated by cell viability, membrane integrity, mitochondrial membrane potential (MMP, reactive oxygen species (ROS assays, and their genotoxicity by comet assay. Our results show that NPs surface passivation reduces the oxidative stress and alteration of iron homeostasis and, consequently, the overall toxicity, despite bare and passivated NPs show similar cell internalization efficiency. We found that the higher toxicity of bare NPs is due to their stronger in-situ degradation, with larger intracellular release of iron ions, as compared to surface passivated NPs. Our results indicate that surface engineering of Fe3O4/SiO2 NPs plays a key role in improving particles stability in biological environments reducing both cytotoxic and genotoxic effects.

Reproductive performance of breeder quails fed diets supplemented with L-cysteine-coated iron oxide nanoparticles.

Science.gov (United States)

Mohammadi, H; Farzinpour, A; Vaziry, A

2017-04-01

The objective of this study was to investigate the effects of L-cysteine-coated iron oxide nanoparticles on reproductive performance in breeder quails. The five treatment diets consisted of (i) negative control diet not supplemented with iron, (ii) positive control diet supplemented with 60 mg/kg of Fe 3 O 4 and (iii) experimental diets supplemented with 0.6, 6 and 60 mg/kg of L-cysteine-coated iron oxide nanoparticles. A total of 100 seven-day-old quail chicks were weighed and randomly placed to five groups of five replicate cages. Four quails (one male and three females) were raised in each cage (50 × 15 × 17 cm). Egg production, feed consumption and egg weight were recorded daily and calculated on a hen per day basis. Egg components, fertility, hatchability and day-old chicks hatched from their eggs were measured at the end of the experiment. The percentage of egg production and egg mass of the 6 mg/kg Fe 3 O 4 -Cys NPs group were significantly higher than those of the control groups. Throughout the experimental period, the highest weekly egg weight was recorded for the 60 mg/kg Fe 3 O 4 -Cys NPs group. Fertility was improved by diet supplemented with iron, both FeSO 4 and Fe 3 O 4 -Cys NPs. The breeder fed Fe 3 O 4 -Cys NPs had the highest day-old chicks weight. The results of this study showed that Fe 3 O 4 nanoparticles that were coated by L-cysteine could improve availability and utilization of iron in diet. Finally, it was proposed that Fe 3 O 4 -Cys NPs could be used as feed additives in quails. © 2017 Blackwell Verlag GmbH.

Gentamicin coated iron oxide nanoparticles as novel antibacterial agents

Science.gov (United States)

Bhattacharya, Proma; Neogi, Sudarsan

2017-09-01

Applications of different types of magnetic nanoparticles for biomedical purposes started a long time back. The concept of surface functionalization of the iron oxide nanoparticles with antibiotics is a novel technique which paves the path for further application of these nanoparticles by virtue of their property of superparamagnetism. In this paper, we have synthesized novel iron oxide nanoparticles surface functionalized with Gentamicin. The average size of the particles, concluded from the HR-TEM images, came to be around 14 nm and 10 nm for unmodified and modified nanoparticles, respectively. The magnetization curve M(H) obtained for these nanoparticles are typical of superparamagnetic nature and having almost zero values of coercivity and remanance. The release properties of the drug coated nanoparticles were studied; obtaining an S shaped profile, indicating the initial burst effect followed by gradual sustained release. In vitro investigations against various gram positive and gram negative strains viz Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Bacillus subtilis indicated significant antibacterial efficiency of the drug-nanoparticle conjugate. The MIC values indicated that a small amount like 0.2 mg ml-1 of drug capped particles induce about 98% bacterial death. The novelty of the work lies in the drug capping of the nanoparticles, which retains the superparamagnetic nature of the iron oxide nanoparticles and the medical properties of the drug simultaneously, which is found to extremely blood compatible.

Annealing effects on magnetic properties of silicone-coated iron-based soft magnetic composites

International Nuclear Information System (INIS)

Wu Shen; Sun Aizhi; Zhai Fuqiang; Wang Jin; Zhang Qian; Xu Wenhuan; Logan, Philip; Volinsky, Alex A.

2012-01-01

This paper focuses on novel iron-based soft magnetic composites synthesis utilizing high thermal stability silicone resin to coat iron powder. The effect of an annealing treatment on the magnetic properties of synthesized magnets was investigated. The coated silicone insulating layer was characterized by scanning electron microscopy and energy dispersive X-ray spectroscopy. Silicone uniformly coated the powder surface, resulting in a reduction of the imaginary part of the permeability, thereby increasing the electrical resistivity and the operating frequency of the synthesized magnets. The annealing treatment increased the initial permeability, the maximum permeability, and the magnetic induction, and decreased the coercivity. Annealing at 580 °C increased the maximum permeability by 72.5%. The result of annealing at 580 °C shows that the ferromagnetic resonance frequency increased from 2 kHz for conventional epoxy resin coated samples to 80 kHz for the silicone resin insulated composites. - Highlights: ► Silicone uniformly coated the powder, increased the operating frequency of SMCs. ► The annealing treatment increased the DC properties of SMCs. ► Annealing at 580 °C increased the maximum permeability by 72.5%. ► Compared with epoxy coated, the SMCs had higher resistivity annealing at 580 °C.

Solid-state Water-mediated Transport Reduction of Nanostructured Iron Oxides

International Nuclear Information System (INIS)

Smirnov, Vladimir M.; Povarov, Vladimir G.; Voronkov, Gennadii P.; Semenov, Valentin G.; Murin, Igor' V.; Gittsovich, Viktor N.; Sinel'nikov, Boris M.

2001-01-01

The Fe 2+ /Fe 3+ ratio in two-dimensional iron oxide nanosructures (nanolayers with a thickness of 0.3-1.5 nm on silica surface) may be precisely controlled using the transport reduction (TR) technique. The species ≡-O-Fe(OH) 2 and (≡Si-O-) 2 -FeOH forming the surface monolayer are not reduced at 400-600 deg. C because of their covalent bonding to the silica surface, as demonstrated by Moessbauer spectroscopy. Iron oxide microparticles (microstructures) obtained by the impregnation technique, being chemically unbound to silica, are subjected to reduction at T ≥ 500 deg. C with formation of metallic iron in the form of α-Fe. Transport reduction of supported nanostructures (consisting of 1 or 4 monolayers) at T ≥ 600 deg. C produces bulk iron(II) silicate and metallic iron phases. The structural-chemical transformations occurring in transport reduction of supported iron oxide nanolayers are proved to be governed by specific phase processes in the nanostructures themselves

Biotemplate synthesis of monodispersed iron phosphate hollow microspheres

International Nuclear Information System (INIS)

Cao Feng; Li Dongxu

2010-01-01

Monodispersed iron phosphate hollow microspheres with a high degree of crystallization were prepared through a facile in situ deposition method using rape pollen grains as a biotemplate. The functional group on the surface of the pollen grains could adsorb Fe 3+ , which provided the nucleation sites for growth of iron phosphate nanoparticles. After being sintered at 600 deg. C for 10 h, the pollen grains were removed and iron phosphate hollow microspheres were obtained. A scanning electron microscope and x-ray diffraction were applied to characterize the morphology and crystalline structure of the pollen grains, iron phosphate-coated pollen grains and iron phosphate hollow microspheres. Differential scanning calorimetry and thermogravity analyses were performed to investigate the thermal behavior of the iron phosphate-coated pollen grains during the calcinations. Energy dispersive spectroscopy and Fourier transform infrared spectroscopy were utilized to investigate the interaction between the pollen grains and iron phosphate. The effect of the pollen wall on the surface morphology of these iron phosphate hollow microspheres was also proven in this work.

Biotemplate synthesis of monodispersed iron phosphate hollow microspheres

Energy Technology Data Exchange (ETDEWEB)

Cao Feng; Li Dongxu, E-mail: dongxuli@njut.edu.c [College of Materials Science and Engineering, Nanjing University of Technology, Jiangsu Nanjing 210009 (China)

2010-03-15

Monodispersed iron phosphate hollow microspheres with a high degree of crystallization were prepared through a facile in situ deposition method using rape pollen grains as a biotemplate. The functional group on the surface of the pollen grains could adsorb Fe{sup 3+}, which provided the nucleation sites for growth of iron phosphate nanoparticles. After being sintered at 600 deg. C for 10 h, the pollen grains were removed and iron phosphate hollow microspheres were obtained. A scanning electron microscope and x-ray diffraction were applied to characterize the morphology and crystalline structure of the pollen grains, iron phosphate-coated pollen grains and iron phosphate hollow microspheres. Differential scanning calorimetry and thermogravity analyses were performed to investigate the thermal behavior of the iron phosphate-coated pollen grains during the calcinations. Energy dispersive spectroscopy and Fourier transform infrared spectroscopy were utilized to investigate the interaction between the pollen grains and iron phosphate. The effect of the pollen wall on the surface morphology of these iron phosphate hollow microspheres was also proven in this work.

Degradation and in vitro cell–material interaction studies on hydroxyapatite-coated biodegradable porous iron for hard tissue scaffolds

Directory of Open Access Journals (Sweden)

Nurizzati Mohd Daud

2014-10-01

Full Text Available This paper describes degradation and cell–material interaction studies on hydroxyapatite (HA-coated biodegradable porous iron proposed for hard tissue scaffolds. Porous iron scaffolds are expected to serve as an ideal platform for bone regeneration. To couple their inherent mechanical strength, pure HA and HA/poly(ε-caprolactone (HA/PCL were coated onto porous iron using dip coating technique. The HA/PCL mixture was prepared to provide a more stable and flexible coating than HA alone. Degradation of the samples was evaluated by weight loss and potentiodynamic polarisation. Human skin fibroblast (HSF and human mesenchymal stem cells (hMSC were put in contact with the samples and their interaction was observed. Results showed that coated samples degraded ∼10 times slower (0.002 mm/year for HA/PCL-Fe, 0.003 mm/year for HA-Fe than the uncoated ones (0.031 mm/year, indicating an inhibition effect of the coating on degradation. Both HSF and hMSC maintained high viability when in contact with the coated samples (100–110% control for hMSC during 2–5 days of incubation, indicating the effect of HA in enhancing cytocompatibility of the surface. This study provided early evidence of the potential translation of biodegradable porous iron scaffolds for clinical use in orthopedic surgery. However, further studies including in vitro and in vivo tests are necessary.

Iron and stony-iron meteorites

DEFF Research Database (Denmark)

Ruzicka, Alex M.; Haack, Henning; Chabot, Nancy L.

2017-01-01

By far most of the melted and differentiated planetesimals that have been sampled as meteorites are metal-rich iron meteorites or stony iron meteorites. The parent asteroids of these meteorites accreted early and differentiated shortly after the solar system formed, producing some of the oldest...... and interpretations for iron and stony iron meteorites (Plate 13.1). Such meteorites provide important constraints on the nature of metal-silicate separation and mixing in planetesimals undergoing partial to complete differentiation. They include iron meteorites that formed by the solidification of cores...... (fractionally crystallized irons), irons in which partly molten metal and silicates of diverse types were mixed together (silicate-bearing irons), stony irons in which partly molten metal and olivine from cores and mantles were mixed together (pallasites), and stony irons in which partly molten metal...

The Effect of Ductile Cast Iron Matrix on Zinc Coating During Hot Dip Galvanising of Castings

Directory of Open Access Journals (Sweden)

D. Kopyciński

2012-12-01

Full Text Available The growth kinetics of the zinc coating formed on the surface of casting made from ductile iron grade EN-GJS-500-3 was investigated. To produce homogenous metal matrix in test samples, the normalising and ferritising annealing was carried out. Studies showeda heterogeneous structure of cast iron with varying content of the phases formed. This was followed by hot dip galvanising treatment at450°C to capture the growth kinetics of the zinc coating (the time of the treatment ranged from 60 to 600 seconds. Nonlinear estimation of the determined growth kinetics of the alloyed layer of a zinc coating was made and an equation of the zinc coating growth was derived.Based on the results of the investigations it was concluded that thickness of the zinc coating formed on the surface of casting with a 100% pearlitic matrix makes 55% of the thickness of coating formed on the surface in 100% ferritic.

The Effect of Ductile Cast Iron Matrix on Zinc Coating During Hot Dip Galvanising of Castings

Directory of Open Access Journals (Sweden)

Kopyciński D.

2012-12-01

Full Text Available The growth kinetics of the zinc coating formed on the surface of casting made from ductile iron grade EN-GJS-500-3 was investigated. To produce homogenous metal matrix in test samples, the normalising and ferritising annealing was carried out. Studies showed a heterogeneous structure of cast iron with varying content of the phases formed. This was followed by hot dip galvanising treatment at 450°C to capture the growth kinetics of the zinc coating (the time of the treatment ranged from 60 to 600 seconds. Nonlinear estimation of the determined growth kinetics of the alloyed layer of a zinc coating was made and an equation of the zinc coating growth was derived. Based on the results of the investigations it was concluded that thickness of the zinc coating formed on the surface of casting with a 100% pearlitic matrix makes 55% of the thickness of coating formed on the surface in 100% ferritic.

Stability of polyelectrolyte-coated iron nanoparticles for T2-weighted magnetic resonance imaging

Science.gov (United States)

McGrath, Andrew J.; Dolan, Ciaran; Cheong, Soshan; Herman, David A. J.; Naysmith, Briar; Zong, Fangrong; Galvosas, Petrik; Farrand, Kathryn J.; Hermans, Ian F.; Brimble, Margaret; Williams, David E.; Jin, Jianyong; Tilley, Richard D.

2017-10-01

Iron nanoparticles are highly-effective magnetic nanoparticles for T2 magnetic resonance imaging (MRI). However, the stability of their magnetic properties is dependent on good protection of the iron core from oxidation in aqueous media. Here we report the synthesis of custom-synthesized phosphonate-grafted polyelectrolytes (PolyM3) of various chain lengths, for efficient coating of iron nanoparticles with a native iron oxide shell. The size of the nanoparticle-polyelectrolyte assemblies was investigated by transmission electron microscopy and dynamic light scattering, while surface attachment was confirmed by Fourier transform infrared spectroscopy. Low cytotoxicity was observed for each of the nanoparticle-polyelectrolyte ("Fe-PolyM3") assemblies, with good cell viability (>80%) remaining up to 100 μg mL-1 Fe in HeLa cells. When applied in T2-weighted MRI, corresponding T2 relaxivities (r2) of the Fe-PolyM3 assemblies were found to be dependent on the chain length of the polyelectrolyte. A significant increase in contrast was observed when polyelectrolyte chain length was increased from 6 to 65 repeating units, implying a critical chain length required for stabilization of the α-Fe nanoparticle core.

Residual Stress Induced by Nitriding and Nitrocarburizing

DEFF Research Database (Denmark)

Somers, Marcel A.J.

2005-01-01

The present chapter is devoted to the various mechanisms involved in the buildup and relief of residual stress in nitrided and nitrocarburized cases. The work presented is an overview of model studies on iron and iron-based alloys. Subdivision is made between the compound (or white) layer......, developing at the surfce and consisting of iron-based (carbo)nitrides, and the diffusion zone underneath, consisting of iron and alloying element nitrides dispersed in af ferritic matrix. Microstructural features are related directly to the origins of stress buildup and stres relief....

TiC Reinforcement Composite Coating Produced Using Graphite of the Cast Iron by Laser Cladding

Directory of Open Access Journals (Sweden)

Yanhui Liu

2016-09-01

Full Text Available In this study, a TiC-reinforced composite coating was produced to improve the wear resistance of a pearlite matrix grey iron using a pre-placed Ti powder by laser cladding. Results of scanning electron microscopy (SEM, X-ray diffractometer (XRD, and energy dispersive X-ray spectroscopy (EDS confirmed that the coating was composed of TiC particles and two kinds of α-Fe phase. The fine TiC particles were only a few microns in size and uniformly distributed on the matrix phase in the composite coating. The microstructure characteristic of the composite coating resulted in the microhardness rising to about 1000 HV0.3 (China GB/T 4342-1991 and the wear resistance significantly increased relative to the substrate. In addition, the fine and homogeneous solidification microstructure without graphite phase in the transition zone led to a good metallurgical bonding and transition between the coating and the substrate. It was of great significance for the cast iron to modify the surface and repair surface defects or surface damage.

TiC Reinforcement Composite Coating Produced Using Graphite of the Cast Iron by Laser Cladding.

Science.gov (United States)

Liu, Yanhui; Qu, Weicheng; Su, Yu

2016-09-30

In this study, a TiC-reinforced composite coating was produced to improve the wear resistance of a pearlite matrix grey iron using a pre-placed Ti powder by laser cladding. Results of scanning electron microscopy (SEM), X-ray diffractometer (XRD), and energy dispersive X-ray spectroscopy (EDS) confirmed that the coating was composed of TiC particles and two kinds of α -Fe phase. The fine TiC particles were only a few microns in size and uniformly distributed on the matrix phase in the composite coating. The microstructure characteristic of the composite coating resulted in the microhardness rising to about 1000 HV0.3 (China GB/T 4342-1991) and the wear resistance significantly increased relative to the substrate. In addition, the fine and homogeneous solidification microstructure without graphite phase in the transition zone led to a good metallurgical bonding and transition between the coating and the substrate. It was of great significance for the cast iron to modify the surface and repair surface defects or surface damage.

Enhanced microwave absorption in ZnO/carbonyl iron nano-composites by coating dielectric material

Energy Technology Data Exchange (ETDEWEB)

Zhou Chang [School of Physics and Material Science, Anhui University, Hefei 230036 (China); Key Laboratory of Opto-electronic Information Acquisition and Manipulation Ministry of Education, Anhui University, Hefei 230039 (China); Fang Qingqing, E-mail: physfangqq@126.com [School of Physics and Material Science, Anhui University, Hefei 230036 (China) and Key Laboratory of Opto-electronic Information Acquisition and Manipulation Ministry of Education, Anhui University, Hefei 230039 (China); Yan Fangliang; Wang Weina; Wu Keyue; Liu Yanmei; Lv Qingrong; Zhang Hanming; Zhang Qiping; Li Jinguang; Ding Qiongqiong [School of Physics and Material Science, Anhui University, Hefei 230036 (China); Key Laboratory of Opto-electronic Information Acquisition and Manipulation Ministry of Education, Anhui University, Hefei 230039 (China)

2012-05-15

The microwave absorption properties of zinc oxide/carbonyl iron composite nanoparticles fabricated by high energy ball milling were studied at 0-20 GHz. Experiments showed that ZnO as a kind of dielectric material coating carbonyl iron particles made the bandwidth of reflection loss (RL)<-5 dB expanding to the low frequency, and enhanced absorption effect obviously. For a 3 mm thickness absorber of ZnO/carbonyl iron after 30 h milling, the values of RL<-5 dB and RL<-8 dB were obtained in the frequency range from 7.0 GHz to 17.8 GHz and from 9.8 dB to 14.9 dB, respectively, and its strongest RL peak was -29.34 dB at 13.59 GHz. The magnetic loss of carbonyl iron particles and the dielectric loss of ZnO particles were the main mechanisms of microwave absorption for the composites. - Highlights: Black-Right-Pointing-Pointer We fabricated zinc oxide/carbonyl iron composites by high energy ball milling. Black-Right-Pointing-Pointer ZnO dielectric property increased absorption effect and absorption bandwidth. Black-Right-Pointing-Pointer Absorbing frequence of composites is expanding to low frequency direction. Black-Right-Pointing-Pointer The craft of high energy ball milling is easy to realize commerce production.

Enhanced microwave absorption in ZnO/carbonyl iron nano-composites by coating dielectric material

International Nuclear Information System (INIS)

Zhou Chang; Fang Qingqing; Yan Fangliang; Wang Weina; Wu Keyue; Liu Yanmei; Lv Qingrong; Zhang Hanming; Zhang Qiping; Li Jinguang; Ding Qiongqiong

2012-01-01

The microwave absorption properties of zinc oxide/carbonyl iron composite nanoparticles fabricated by high energy ball milling were studied at 0–20 GHz. Experiments showed that ZnO as a kind of dielectric material coating carbonyl iron particles made the bandwidth of reflection loss (RL)<−5 dB expanding to the low frequency, and enhanced absorption effect obviously. For a 3 mm thickness absorber of ZnO/carbonyl iron after 30 h milling, the values of RL<−5 dB and RL<−8 dB were obtained in the frequency range from 7.0 GHz to 17.8 GHz and from 9.8 dB to 14.9 dB, respectively, and its strongest RL peak was −29.34 dB at 13.59 GHz. The magnetic loss of carbonyl iron particles and the dielectric loss of ZnO particles were the main mechanisms of microwave absorption for the composites. - Highlights: ► We fabricated zinc oxide/carbonyl iron composites by high energy ball milling. ► ZnO dielectric property increased absorption effect and absorption bandwidth. ► Absorbing frequence of composites is expanding to low frequency direction. ► The craft of high energy ball milling is easy to realize commerce production.

On Degradation of Cast Iron Surface-Protective Paint Coat Joint

Directory of Open Access Journals (Sweden)

Tupaj M.

2016-09-01

Full Text Available The paper is a presentation of a study on issues concerning degradation of protective paint coat having an adverse impact on aesthetic qualities of thin-walled cast-iron castings fabricated in furan resin sand. Microscopic examination and microanalyses of chemistry indicated that under the coat of paint covering the surface of a thin-walled casting, layers of oxides could be found presence of which can be most probably attributed to careless cleaning of the casting surface before the paint application process, as well as corrosion pits evidencing existence of damp residues under the paint layers contributing to creation of corrosion micro-cells

The shaping of zinc coating on surface steels and ductile iron casting

Directory of Open Access Journals (Sweden)

D. Kopyciński

2010-01-01

Full Text Available The studies aimed at an analysis of the formation and growth kinetics of zinc coating on reactive silicon-killed steels in a zinc bath. The growth kinetics of the produced zinc coatings was evaluated basing on the power-law growth equation. As regards galvanizing of the surface of products, investigation was done for various steel grades and ductile iron (DI taking into account the quality and thickness of coating. It has been proved that the chemical constitution of basis significantly influences the kinetics of growth of the individual phases in a zinc coating. This relationship was evaluated basing on the, so called, silicon and phosphorus equivalent ESi,P and coating thickness dependences were obtained.

Application of cylinder symmetry to iron and titanium oxidation by oxygen or hydrogen-water vapour mixes

International Nuclear Information System (INIS)

Raynaud, Pierre

1980-01-01

This research thesis addresses the study of the oxidation reaction in the case of corrosion of iron by oxygen, hydrogen sulphide or hydrogen-water vapour mixes, and in the case of oxidation of titanium and of titanium nitride by hydrogen-water vapour mixes. It first addresses the corrosion of iron by oxygen with an experiment performed in cylinder symmetry: description of operational conditions, discussion of kinetic curves, development of a law of generation of multiple layers in cylinder symmetry, analytical exploitation of experimental results. The second part addresses the oxidation of iron by hydrogen-water vapour mixes: experimental conditions, influence of temperature on kinetics, micrographic study (oxide morphology, coating morphology, interpretation of differences with the case of plane symmetry), discussion of the influence of cylinder symmetry on oxidation kinetics. The third part addresses the oxidation of titanium by hydrogen-water vapour mixes: global kinetic evolution, reaction products and micrographic examination, morphology and texture studies, discussion of the oxidation mechanism and of cylinder symmetry [fr

Reductive Degradation of Perfluorinated Compounds in Water using Mg-aminoclay coated Nanoscale Zero Valent Iron

OpenAIRE

Arvaniti, Olga S.; Hwang, Yuhoon; Andersen, Henrik Rasmus; Stasinakis, Athanasios S.; Thomaidis , Nikolaos S.; Aloupi, Maria

2015-01-01

Perfluorinated Compounds (PFCs) are extremely persistent micropollutants that are detected worldwide. We studied the removal of PFCs (perfluorooctanoic acid; PFOA, perfluorononanoic acid; PFNA, perfluorodecanoic acid; PFDA and perfluorooctane sulfonate; PFOS) from water by different types of nanoscale zero-valent iron (nZVI). Batch experiments showed that an iron dose of 1 g•L-1 in the form of Mg-aminoclay (MgAC) coated nZVI, at an initial pH of 3.0 effectively removed 38 % to 96 % of individ...

Effect of the Surface Layer of Iron Casting on the Growth of Protective Coating During Hot-Dip Galvanizing

Directory of Open Access Journals (Sweden)

Kopyciński D.

2016-03-01

Full Text Available The paper presents the results of investigations of the growth of protective coating on the surface of ductile iron casting during the hot-dip galvanizing treatment. Ductile iron of the EN-GJS-600-3 grade was melted and two moulds made by different technologies were poured to obtain castings with different surface roughness parameters. After the determination of surface roughness, the hot-dip galvanizing treatment was carried out. Based on the results of investigations, the effect of casting surface roughness on the kinetics of the zinc coating growth was evaluated. It was found that surface roughness exerts an important effect on the thickness of produced zinc coating.

Failure Mechanisms of the Protective Coatings for the Hot Stamping Applications

Science.gov (United States)

Zhao, Chen

In the present study, four different nitriding techniques were carried on the ductile irons NAAMS-D6510 and cast steels NAAMS-S0050A, which are widely used stamping die materials; duplex treatments (PVD CrN coating+nitriding) were carried on H13 steels, which are common inserts for the hot stamping dies. Inclined impact-sliding wear tests were performed on the nitriding cases under simulated stamping conditions. Surface profilometer, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) were used to investigate the wear and failure mechanisms of the protective coatings. It was found that the nitrided ductile iron samples performed better than the nitrided cast steel specimens. High temperature inclined impact-sliding wear tests were carried out on the CrN coatings. It was found that the coating performed better at elevated temperature. XPS analysis indicated the top surface layer (about 3-4nm) of the coating was oxidized at 400 °C and formed a Cr2O3 protective film. The in-situ formation of the thin Cr2O3 protective layer likely led to the change of wear mechanisms from severe adhesive failure to mild abrasive wear.

Catalytic Ozonation by Iron Coated Pumice for the Degradation of Natural Organic Matters

Directory of Open Access Journals (Sweden)

Alper Alver

2018-05-01

Full Text Available The use of iron-coated pumice (ICP in heterogeneous catalytic ozonation significantly enhanced the removal efficiency of natural organic matters (NOMs in water, due to the synergistic effect of hybrid processes when compared to sole ozonation and adsorption. Multiple characterization analyses (BET, TEM, XRD, DLS, FT-IR, and pHPZC were employed for a systematic investigation of the catalyst surface properties. This analysis indicated that the ICP crystal structure was α-FeOOH, the surface hydroxyl group of ICP was significantly increased after coating, the particle size of ICP was about 200–250 nm, the BET surface area of ICP was about 10.56 m2 g−1, the pHPZC value of ICP was about 7.13, and that enhancement by iron loading was observed in the FT-IR spectra. The contribution of surface adsorption, hydroxyl radicals, and sole ozonation to catalytic ozonation was determined as 21.29%, 66.22%, and 12.49%, respectively. The reaction kinetic analysis with tert-Butyl alcohol (TBA was used as a radical scavenger, confirming that surface ferrous iron loading promoted the role of the hydroxyl radicals. The phosphate was used as an inorganic probe, and significantly inhibited the removal efficiency of catalytic NOM ozonation. This is an indication that the reactions which occur are more dominant in the solution phase.

Conversion electron Moessbauer spectroscopic studies on the chemical states of surface layers of corroded tin plates and tin-coated iron plates

International Nuclear Information System (INIS)

Kato, Akinori; Endo, Kazutoyo; Sano, Hirotoshi

1980-01-01

By means of the conversion electron Moessbauer spectroscopy (CEMS), we studied surface layers of ''tin'' plates and tin-coated iron plates corroded by various acids. Transmission Moessbauer spectra and X-ray diffraction patterns were also measured. Metastannic acid was formed, when the ''tin'' plate was corroded by nitric acid solution. In corrosion by phosphoric acid solution, the X-ray diffractometry revealed the formation of tin(IV) pyrophosphate. In corrosion by various organic acid solutions, the formation of oxides was identified by the 119 Sn CEMS, but not by the X-ray diffractometry because of the too thin corrosion layer. In corrosion of tin-coated iron plates, maleic acid, malonic acid, formic acid, and oxalic acid were used. It was determined by CEMS that the corrosion products caused by these acids were tin(IV) oxides, although they could not be identified by the X-ray diffractometry. CEMS also confirmed that the surface of uncorroded tin-coated iron plate was already oxidized by air. Colorimetric determinations of Sn and Fe dissolved from tin-coated iron plates to various acid solutions confirmed that maleic acid had the strongest corrosion effect among the organic acids studied. (author)

Superparamagnetic iron oxides for MRI

International Nuclear Information System (INIS)

Weissleder, R.; Reimer, P.

1993-01-01

Pharmaceutical iron oxide preparations have been used as MRI contrast agents for a variety of purposes. These agents predominantly decrease T2 relaxation times and therefore cause a decrease in signal intensity of tissues that contain the agent. After intravenous administration, dextran-coated iron oxides typically accumulate in phagocytic cells in liver and spleen. Clinical trials have shown that iron oxide increases lesion/liver and lesion/spleen contrast, that more lesions can be depicted than on plain MRI or CT, and that the size threshold for lesion detection decreases. Decreased uptake of iron oxides in liver has been observed in hepatitis and cirrhosis, potentially allowing the assessment of organ function. More recently a variety of novel, target-specific monocrystalline iron oxides compounds have been used for receptor and immunospecific images. Future development of targeted MRI contrast agents is critical for organ- or tissue-specific quantitative and functional MRI. (orig.)

Superparamagnetic iron oxides for MRI

Energy Technology Data Exchange (ETDEWEB)

Weissleder, R [MGH-NMR Center, Dept. of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Reimer, P [MGH-NMR Center, Dept. of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); [Inst. fuer Klinische Radiologie, Zentrale Roentgendiagnostik, Westfaelische-Wilhelms-Univ., Muenster (Germany)

1993-06-01

Pharmaceutical iron oxide preparations have been used as MRI contrast agents for a variety of purposes. These agents predominantly decrease T2 relaxation times and therefore cause a decrease in signal intensity of tissues that contain the agent. After intravenous administration, dextran-coated iron oxides typically accumulate in phagocytic cells in liver and spleen. Clinical trials have shown that iron oxide increases lesion/liver and lesion/spleen contrast, that more lesions can be depicted than on plain MRI or CT, and that the size threshold for lesion detection decreases. Decreased uptake of iron oxides in liver has been observed in hepatitis and cirrhosis, potentially allowing the assessment of organ function. More recently a variety of novel, target-specific monocrystalline iron oxides compounds have been used for receptor and immunospecific images. Future development of targeted MRI contrast agents is critical for organ- or tissue-specific quantitative and functional MRI. (orig.)

Iron and stony-iron meteorites

DEFF Research Database (Denmark)

Benedix, Gretchen K.; Haack, Henning; McCoy, T. J.

2014-01-01

Without iron and stony-iron meteorites, our chances of ever sampling the deep interior of a differentiated planetary object would be next to nil. Although we live on a planet with a very substantial core, we will never be able to sample it. Fortunately, asteroid collisions provide us with a rich...... sampling of the deep interiors of differentiated asteroids. Iron and stony-iron meteorites are fragments of a large number of asteroids that underwent significant geological processing in the early solar system. Parent bodies of iron and some stony-iron meteorites completed a geological evolution similar...... to that continuing on Earth – although on much smaller length- and timescales – with melting of the metal and silicates; differentiation into core, mantle, and crust; and probably extensive volcanism. Iron and stony-iron meteorites are our only available analogues to materials found in the deep interiors of Earth...

Magnetic properties of iron-based soft magnetic composites with SiO{sub 2} coating obtained by reverse microemulsion method

Energy Technology Data Exchange (ETDEWEB)

Wu, Shen [School of Material Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083 (China); Sun, Aizhi, E-mail: sunaizhi@126.com [School of Material Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083 (China); Lu, Zhenwen; Cheng, Chuan [School of Material Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Gao, Xuexu [State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083 (China)

2015-05-01

In this work, iron-based soft magnetic composites coated with the amorphous SiO{sub 2} layer have been fabricated by utilizing tetraethoxysilane in the reverse microemulsion method, and then the effects of addition amount of SiO{sub 2} and annealing temperature on the magnetic properties were investigated. The results show that the surface of iron powders contains a thin amorphous SiO{sub 2} insulation layer, which effectively decreases the magnetic loss of synthesized magnets. The magnetic loss of coated samples decreased by 87.8% as compared with that of uncoated samples at 150 kHz. Magnetic measurements show that the sample with 1.25 wt% SiO{sub 2} has an acceptable real part and minimum imaginary part of permeability in comparison with other samples. Also, the annealing treatment increased the initial permeability, the maximum permeability and the magnetic induction and decreased the coercivity with increasing temperature in the range 300–600 °C. The results of the loss separation imply that the annealed SMCs have a higher hysteresis loss coefficient (k{sub 2}) and lower eddy current loss coefficient (k{sub 3}) as compared with the pure iron compacts after the same heat treatment due to the preservation of the SiO{sub 2} layer. - Highlights: • SiO{sub 2} coated the iron powder by reverse microemulsion method, decreased the magnetic loss of SMCs. • 25 wt% is the optimum coating amount to attain the desired permeability. • The influence of annealing temperature on the magnetic performance of the core was discussed. • Compare with the pure iron compacts, the annealed SMCs have lower value of eddy current coefficient.

Electrochemical Study of Polymer and Ceramic-Based Nanocomposite Coatings for Corrosion Protection of Cast Iron Pipeline

Directory of Open Access Journals (Sweden)

Ameen Uddin Ammar

2018-02-01

Full Text Available Coating is one of the most effective measures to protect metallic materials from corrosion. Various types of coatings such as metallic, ceramic and polymer coatings have been investigated in a quest to find durable coatings to resist electrochemical decay of metals in industrial applications. Many polymeric composite coatings have proved to be resistant against aggressive environments. Two major applications of ferrous materials are in marine environments and in the oil and gas industry. Knowing the corroding behavior of ferrous-based materials during exposure to these aggressive applications, an effort has been made to protect the material by using polymeric and ceramic-based coatings reinforced with nano materials. Uncoated and coated cast iron pipeline material was investigated during corrosion resistance by employing EIS (electrochemical impedance spectroscopy and electrochemical DC corrosion testing using the “three electrode system”. Cast iron pipeline samples were coated with Polyvinyl Alcohol/Polyaniline/FLG (Few Layers Graphene and TiO2/GO (graphene oxide nanocomposite by dip-coating. The EIS data indicated better capacitance and higher impedance values for coated samples compared with the bare metal, depicting enhanced corrosion resistance against seawater and “produce water” of a crude oil sample from a local oil rig; Tafel scans confirmed a significant decrease in corrosion rate of coated samples.

Iron/iron oxide core-shell nanoclusters for biomedical applications

International Nuclear Information System (INIS)

Qiang You; Antony, Jiji; Sharma, Amit; Nutting, Joseph; Sikes, Daniel; Meyer, Daniel

2006-01-01

Biocompatible magnetic nanoparticles have been found promising in several biomedical applications for tagging, imaging, sensing and separation in recent years. Most magnetic particles or beads currently used in biomedical applications are based on ferromagnetic iron oxides with very low specific magnetic moments of about 20-30 emu/g. Here we report a new approach to synthesize monodispersed core-shell nanostructured clusters with high specific magnetic moments above 200 emu/g. Iron nanoclusters with monodispersive size of diameters from 2 nm to 100 nm are produced by our newly developed nanocluster source and go to a deposition chamber, where a chemical reaction starts, and the nanoclusters are coated with iron oxides. HRTEM Images show the coatings are very uniform and stable. The core-shell nanoclusters are superparamagnetic at room temperature for sizes less than 15 nm, and then become ferromagnetic when the cluster size increases. The specific magnetic moment of core-shell nanoclusters is size dependent, and increases rapidly from about 80 emu/g at the cluster size of around 3 nm to over 200 emu/g up to the size of 100 nm. The use of high magnetic moment nanoclusters for biomedical applications could dramatically enhance the contrast for MRI, reduce the concentration of magnetic particle needs for cell separation, or make drug delivery possible with much lower magnetic field gradients

Tuning dipolar magnetic interactions by controlling individual silica coating of iron oxide nanoparticles

Science.gov (United States)

Rivas Rojas, P. C.; Tancredi, P.; Moscoso Londoño, O.; Knobel, M.; Socolovsky, L. M.

2018-04-01

Single and fixed size core, core-shell nanoparticles of iron oxides coated with a silica layer of tunable thickness were prepared by chemical routes, aiming to generate a frame of study of magnetic nanoparticles with controlled dipolar interactions. The batch of iron oxides nanoparticles of 4.5 nm radii, were employed as cores for all the coated samples. The latter was obtained via thermal decomposition of organic precursors, resulting on nanoparticles covered with an organic layer that was subsequently used to promote the ligand exchange in the inverse microemulsion process, employed to coat each nanoparticle with silica. The amount of precursor and times of reaction was varied to obtain different silica shell thicknesses, ranging from 0.5 nm to 19 nm. The formation of the desired structures was corroborated by TEM and SAXS measurements, the core single-phase spinel structure was confirmed by XRD, and superparamagnetic features with gradual change related to dipolar interaction effects were obtained by the study of the applied field and temperature dependence of the magnetization. To illustrate that dipolar interactions are consistently controlled, the main magnetic properties are presented and analyzed as a function of center to center minimum distance between the magnetic cores.

Health implications of PAH release from coated cast iron drinking water distribution systems in The Netherlands.

Science.gov (United States)

Blokker, E J Mirjam; van de Ven, Bianca M; de Jongh, Cindy M; Slaats, P G G Nellie

2013-05-01

Coal tar and bitumen have been historically used to coat the insides of cast iron drinking water mains. Polycyclic aromatic hydrocarbons (PAHs) may leach from these coatings into the drinking water and form a potential health risk for humans. We estimated the potential human cancer risk from PAHs in coated cast iron water mains. In a Dutch nationwide study, we collected drinking water samples at 120 locations over a period of 17 days under various operational conditions, such as undisturbed operation, during flushing of pipes, and after a mains repair, and analyzed these samples for PAHs. We then estimated the health risk associated with an exposure scenario over a lifetime. During flushing, PAH levels frequently exceeded drinking water quality standards; after flushing, these levels dropped rapidly. After the repair of cast iron water mains, PAH levels exceeded the drinking water standards for up to 40 days in some locations. The estimated margin of exposure for PAH exposure through drinking water was > 10,000 for all 120 measurement locations, which suggests that PAH exposure through drinking water is of low concern for consumer health. However, factors that differ among water systems, such as the use of chlorination for disinfection, may influence PAH levels in other locations.

Iron crystallization in a fluidized-bed Fenton process.

Science.gov (United States)

Boonrattanakij, Nonglak; Lu, Ming-Chun; Anotai, Jin

2011-05-01

The mechanisms of iron precipitation and crystallization in a fluidized-bed reactor were investigated. Within the typical Fenton's reagent dosage and pH range, ferric ions as a product from ferrous ion oxidation would be supersaturated and would subsequently precipitate out in the form of ferric hydroxide after the initiation of the Fenton reaction. These precipitates would simultaneously crystallize onto solid particles in a fluidized-bed Fenton reactor if the precipitation proceeded toward heterogeneous nucleation. The heterogeneous crystallization rate was controlled by the fluidized material type and the aging/ripening period of the crystallites. Iron crystallization onto the construction sand was faster than onto SiO(2), although the iron removal efficiencies at 180 min, which was principally controlled by iron hydroxide solubility, were comparable. To achieve a high iron removal rate, fluidized materials have to be present at the beginning of the Fenton reaction. Organic intermediates that can form ferro-complexes, particularly volatile fatty acids, can significantly increase ferric ion solubility, hence reducing the crystallization performance. Therefore, the fluidized-bed Fenton process will achieve exceptional performance with respect to both organic pollutant removal and iron removal if it is operated with the goal of complete mineralization. Crystallized iron on the fluidized media could slightly retard the successive crystallization rate; thus, it is necessary to continuously replace a portion of the iron-coated bed with fresh media to maintain iron removal performance. The iron-coated construction sand also had a catalytic property, though was less than those of commercial goethite. Copyright © 2011 Elsevier Ltd. All rights reserved.

Synthesis, Characterization, and Toxicity Evaluation of Dextran-Coated Iron Oxide Nanoparticles

Directory of Open Access Journals (Sweden)

Mihaela Balas

2017-02-01

Full Text Available We report the synthesis of dextran-coated iron oxide magnetic nanoparticles (DIO-NPs with spherical shape and uniform size distribution as well as their accumulation and toxic effects on Jurkat cells up to 72 h. The characterization of dextran-coated maghemite nanoparticles was done by X-ray diffraction and dynamic light scattering analyses, transmission electron microscopy imaging, attenuated total reflectance Fourier transform infrared (ATR-FTIR spectroscopy, magnetic hysteresis, and relaxometry measurements. The quantification of DIO-NPs intracellular uptake showed a progressive accumulation of iron as a function of time and dose accompanied by additional lysosome formation and an increasing darkening exhibited by a magnetic resonance imaging (MRI scanner. The cytotoxicity assays revealed a decrease of cell viability and a loss of membrane integrity in a time- and dose-dependent manner. Exposure to DIO-NPs determined an increase in reactive oxygen species level up to 72 h. In the first two days of exposure, the level of reduced glutathione decreased and the amount of malondyaldehyde increased, but at the end of the experiment, their concentrations returned to control values. These nanoparticles could be used as contrast agents for MRI but several parameters concerning their interaction with the cells should be taken into consideration for a safe utilization.

A Study on DLC Tool Coating for Deep Drawing and Ironing of Stainless Steel

DEFF Research Database (Denmark)

Üstünyagiz, Esmeray; Hafis Sulaiman, Mohd; Christiansen, Peter

2018-01-01

) to replicate industrial ironing of deep drawn, stainless steel parts. Non-hazardous tribo-systems in form of a double layer Diamond-like coated tool applied under dry condition or with an environmentally friendly lubricant were investigated via emulating industrial process conditions in laboratory tests...

Superparamagnetic iron oxide nanoparticles (SPIONs)-loaded Trojan microparticles for targeted aerosol delivery to the lung.

Science.gov (United States)

Tewes, Frederic; Ehrhardt, Carsten; Healy, Anne Marie

2014-01-01

Targeted aerosol delivery to specific regions of the lung may improve therapeutic efficiency and minimise unwanted side effects. Targeted delivery could potentially be achieved with porous microparticles loaded with superparamagnetic iron oxide nanoparticles (SPIONs)-in combination with a target-directed magnetic gradient field. The aim of this study was to formulate and evaluate the aerodynamic properties of SPIONs-loaded Trojan microparticles after delivery from a dry powder inhaler. Microparticles made of SPIONs, PEG and hydroxypropyl-β-cyclodextrin (HPβCD) were formulated by spray drying and characterised by various physicochemical methods. Aerodynamic properties were evaluated using a next generation cascade impactor (NGI), with or without a magnet positioned at stage 2. Mixing appropriate proportions of SPIONs, PEG and HPβCD allowed Trojan microparticle to be formulated. These particles had a median geometric diameter of 2.8±0.3μm and were shown to be sensitive to the magnetic field induced by a magnet having a maximum energy product of 413.8kJ/m(3). However, these particles, characterised by a mass median aerodynamic diameter (MMAD) of 10.2±2.0μm, were considered to be not inhalable. The poor aerodynamic properties resulted from aggregation of the particles. The addition of (NH4)2CO3 and magnesium stearate (MgST) to the formulation improved the aerodynamic properties of the Trojan particles and resulted in a MMAD of 2.2±0.8μm. In the presence of a magnetic field on stage 2 of the NGI, the amount of particles deposited at this stage increased 4-fold from 4.8±0.7% to 19.5±3.3%. These Trojan particles appeared highly sensitive to the magnetic field and their deposition on most of the stages of the NGI was changed in the presence compared to the absence of the magnet. If loaded with a pharmaceutical active ingredient, these particles may be useful for treating localised lung disease such as cancer nodules or bacterial infectious foci. Copyright �

Influence of iron and beryllium additions on heat resistance of silicide coatings on TsMB-30 molybdenum alloy

International Nuclear Information System (INIS)

Zajtseva, A.L.; Fedorchuk, N.M.; Lazarev, Eh.M.; Korotkov, N.A.

1985-01-01

Alloying of titanium modified silicide coatings on TsMB-30 molybdenum alloy with iron or beryllium is stated to improve their protective properties. Coatings with low content of alloying elements have the best protective properties. Service life of coatings is determined by the formed oxide film and phase transformations taking place in the coating

Caveolin-1 and CDC42 mediated endocytosis of silica-coated iron oxide nanoparticles in HeLa cells

Directory of Open Access Journals (Sweden)

Nils Bohmer

2015-01-01

Full Text Available Nanomedicine is a rapidly growing field in nanotechnology, which has great potential in the development of new therapies for numerous diseases. For example iron oxide nanoparticles are in clinical use already in the thermotherapy of brain cancer. Although it has been shown, that tumor cells take up these particles in vitro, little is known about the internalization routes. Understanding of the underlying uptake mechanisms would be very useful for faster and precise development of nanoparticles for clinical applications. This study aims at the identification of key proteins, which are crucial for the active uptake of iron oxide nanoparticles by HeLa cells (human cervical cancer as a model cell line. Cells were transfected with specific siRNAs against Caveolin-1, Dynamin 2, Flotillin-1, Clathrin, PIP5Kα and CDC42. Knockdown of Caveolin-1 reduces endocytosis of superparamagnetic iron oxide nanoparticles (SPIONs and silica-coated iron oxide nanoparticles (SCIONs between 23 and 41%, depending on the surface characteristics of the nanoparticles and the experimental design. Knockdown of CDC42 showed a 46% decrease of the internalization of PEGylated SPIONs within 24 h incubation time. Knockdown of Dynamin 2, Flotillin-1, Clathrin and PIP5Kα caused no or only minor effects. Hence endocytosis in HeLa cells of iron oxide nanoparticles, used in this study, is mainly mediated by Caveolin-1 and CDC42. It is shown here for the first time, which proteins of the endocytotic pathway mediate the endocytosis of silica-coated iron oxide nanoparticles in HeLa cells in vitro. In future studies more experiments should be carried out with different cell lines and other well-defined nanoparticle species to elucidate possible general principles.

Iron Refractory Iron Deficiency Anaemia: A Rare Cause of Iron Deficiency Anaemia

LENUS (Irish Health Repository)

McGrath, T

2018-01-01

We describe the case of a 17-month-old boy with a hypochromic microcytic anaemia, refractory to oral iron treatment. After exclusion of dietary and gastrointestinal causes of iron deficiency, a genetic cause for iron deficiency was confirmed by finding two mutations in the TMPRSS6 gene, consistent with a diagnosis of iron-refractory iron deficiency anaemia (IRIDA).

Rapid microwave-assisted synthesis of dextran-coated iron oxide nanoparticles for magnetic resonance imaging

International Nuclear Information System (INIS)

Osborne, Elizabeth A; Atkins, Tonya M; Kauzlarich, Susan M; Gilbert, Dustin A; Liu Kai; Louie, Angelique Y

2012-01-01

Currently, magnetic iron oxide nanoparticles are the only nanosized magnetic resonance imaging (MRI) contrast agents approved for clinical use, yet commercial manufacturing of these agents has been limited or discontinued. Though there is still widespread demand for these particles both for clinical use and research, they are difficult to obtain commercially, and complicated syntheses make in-house preparation unfeasible for most biological research labs or clinics. To make commercial production viable and increase accessibility of these products, it is crucial to develop simple, rapid and reproducible preparations of biocompatible iron oxide nanoparticles. Here, we report a rapid, straightforward microwave-assisted synthesis of superparamagnetic dextran-coated iron oxide nanoparticles. The nanoparticles were produced in two hydrodynamic sizes with differing core morphologies by varying the synthetic method as either a two-step or single-step process. A striking benefit of these methods is the ability to obtain swift and consistent results without the necessity for air-, pH- or temperature-sensitive techniques; therefore, reaction times and complex manufacturing processes are greatly reduced as compared to conventional synthetic methods. This is a great benefit for cost-effective translation to commercial production. The nanoparticles are found to be superparamagnetic and exhibit properties consistent for use in MRI. In addition, the dextran coating imparts the water solubility and biocompatibility necessary for in vivo utilization. (paper)

Rapid microwave-assisted synthesis of dextran-coated iron oxide nanoparticles for magnetic resonance imaging.

Science.gov (United States)

Osborne, Elizabeth A; Atkins, Tonya M; Gilbert, Dustin A; Kauzlarich, Susan M; Liu, Kai; Louie, Angelique Y

2012-06-01

Currently, magnetic iron oxide nanoparticles are the only nanosized magnetic resonance imaging (MRI) contrast agents approved for clinical use, yet commercial manufacturing of these agents has been limited or discontinued. Though there is still widespread demand for these particles both for clinical use and research, they are difficult to obtain commercially, and complicated syntheses make in-house preparation unfeasible for most biological research labs or clinics. To make commercial production viable and increase accessibility of these products, it is crucial to develop simple, rapid and reproducible preparations of biocompatible iron oxide nanoparticles. Here, we report a rapid, straightforward microwave-assisted synthesis of superparamagnetic dextran-coated iron oxide nanoparticles. The nanoparticles were produced in two hydrodynamic sizes with differing core morphologies by varying the synthetic method as either a two-step or single-step process. A striking benefit of these methods is the ability to obtain swift and consistent results without the necessity for air-, pH- or temperature-sensitive techniques; therefore, reaction times and complex manufacturing processes are greatly reduced as compared to conventional synthetic methods. This is a great benefit for cost-effective translation to commercial production. The nanoparticles are found to be superparamagnetic and exhibit properties consistent for use in MRI. In addition, the dextran coating imparts the water solubility and biocompatibility necessary for in vivo utilization.

Microplasma synthesis on aluminum with additions of iron and nickel soluble complexes in electrolyte

Energy Technology Data Exchange (ETDEWEB)

Rogov, A.B., E-mail: alex-lab@bk.ru [Nikolaev Institute of Inorganic Chemistry. 3, Acad. Lavrentiev Ave, Novosibirsk, 630090 (Russian Federation); Mironov, I.V.; Terleeva, O.P.; Slonova, A.I. [Nikolaev Institute of Inorganic Chemistry. 3, Acad. Lavrentiev Ave, Novosibirsk, 630090 (Russian Federation)

2012-10-01

Highlights: Black-Right-Pointing-Pointer Alkaline homogeneous electrolyte with transition metals complexes. Black-Right-Pointing-Pointer Coatings contain metallic iron, nickel and their oxides in alumina-silica matrix. Black-Right-Pointing-Pointer Effect of Fe/Ni ratio on coatings properties and process characteristics. - Abstract: The microplasma synthesis of coatings containing iron and nickel from homogeneous electrolytes has been studied. For stabilization of transition metals in solution, it is proposed to use chelation. It was found that the synthesis of coatings using alternating current leads to the formation of metallic iron and nickel particles in addition to oxide phases. The iron and nickel complexes concentrations ratio in the electrolyte correlates with the coatings composition. Obtained coatings have been studied by scanning electron microscopy with X-ray microanalyser and by X-ray diffraction with Cu and Mo radiation. The metal content in the coating was determined spectrophotometrically from the absorption of iron thiocyanate complexes and nickel dimethylglyoxime complex.

Leachability of nitrided ilmenite in hydrochloric acid

CSIR Research Space (South Africa)

Swanepoel, JJ

2010-10-01

Full Text Available Titanium nitride in upgraded nitrided ilmenite (bulk of iron removed) can selectively be chlorinated to produce titanium tetrachloride. Except for iron, most other components present during this low temperature (ca. 200 °C) chlorination reaction...

A Study on Removal of Environmental Pollution Materials with Nano-scale Iron Particles

Energy Technology Data Exchange (ETDEWEB)

Lee, Myung Ho; Ahn, Hong Ju

2009-07-15

In this study, a method of nano-sized iron particles with zero valent state was developed. Also, the optimum conditions for the synthesis of silica based micro-particles were obtained for micro particle analysis. Basic physical data for standard particles were obtained in various synthesis conditions for mass production. From the experiment of removal of Pb in the solution with iron particles with zero valent state, most of Pb was removed from the solution over pH 7, as a result of reaction of Pb with iron particles with zero valent state. Nano sized iron particles with zero valent state obtained from this study will be apply for removing heavy metals and radionuclides as well as waste treatment and remediation for contaminated materials in the environment.

Formulation design for target delivery of iron nanoparticles to TCE zones.

Science.gov (United States)

Wang, Ziheng; Acosta, Edgar

2013-12-01

Nanoparticles of zero-valent iron (NZVI) are effective reducing agents for some dense non-aqueous phase liquid (DNAPL) contaminants such as trichloroethylene (TCE). However, target delivery of iron nanoparticles to DNAPL zones in the aquifer remains an elusive feature for NZVI technologies. This work discusses three strategies to deliver iron nanoparticles to DNAPL zones. To this end, iron oxide nanoparticles coated with oleate (OL) ions were used as stable analogs for NZVI. The OL-coated iron oxide nanoparticles are rendered lipophilic via (a) the addition of CaCl2, (b) acidification, or (c) the addition of a cationic surfactant, benzethonium chloride (BC). Mixtures of OL and BC show promise as a target delivery strategy due to the high stability of the nanoparticles in water, and their preferential partition into TCE in batch experiments. Column tests show that while the OL-BC coated iron oxide nanoparticles remain largely mobile in TCE-free columns, a large fraction of these particles are retained in TCE-contaminated columns, confirming the effectiveness of this target delivery strategy. © 2013.

Effect of surfactant-coated iron oxide nanoparticles on the effluent water quality from a simulated sequencing batch reactor treating domestic wastewater

International Nuclear Information System (INIS)

Hwang, Sangchul; Martinez, Diana; Perez, Priscilla; Rinaldi, Carlos

2011-01-01

This study was conducted to evaluate the effect of commercially available engineered iron oxide nanoparticles coated with a surfactant (ENP Fe-surf ) on effluent water quality from a lab-scale sequencing batch reactor as a model secondary biological wastewater treatment. Results showed that ∼8.7% of ENP Fe-surf applied were present in the effluent stream. The stable presence of ENP Fe-surf was confirmed by analyzing the mean particle diameter and iron concentration in the effluent. Consequently, aqueous ENP Fe-surf deteriorated the effluent water quality at a statistically significant level (p Fe-surf would be introduced into environmental receptors through the treated effluent and could potentially impact them. - Highlights: → Surfactant-coated engineered iron oxide nanoparticles (ENP Fe-surf ) were assessed. → Effluent quality was analyzed from a sequencing batch reactor with ENP Fe-surf . → ∼8.7% of ENP Fe-surf applied was present in the effluent. → ENP Fe-surf significantly (p Fe-surf will be introduced into environmental receptors. - Stable presence of surfactant-coated engineered iron oxides nanoparticles deteriorated the effluent water quality at a statistically significant level (p < 0.05).

Effect of Initial Iron Content in a Zinc Bath on the Dissolution Rate of Iron During a Hot Dip Galvanizing Process

Science.gov (United States)

Lee, Sang Myung; Lee, Suk Kyu; Paik, Doo-Jin; Park, Joo Hyun

2017-04-01

The mechanism of iron dissolution and the effect of initial Fe content in a Zn bath on the dissolution rate of iron were investigated using a finger rotating method (FRM). When the initial iron content, [Fe]°, in the zinc bath was less than the solubility limit, the iron content in the zinc bath showed a rapid increase, whereas a moderate increase was observed when [Fe]° was close to the solubility limit. Based on Eisenberg's kinetic model, the mass transfer coefficient of iron in the present experimental condition was calculated to be k M = 1.2 × 10-5 m/s, which was similar to the results derived by Giorgi et al. under industrial practice conditions. A dissolution of iron occurred even when the initial iron content in the zinc bath was greater than the solubility limit, which was explained by the interfacial thermodynamics in conjunction with the morphology of the surface coating layer. By analyzing the diffraction patterns using TEM, the outermost dendritic-structured coating layer was confirmed as FeZn13 ( ζ). In order to satisfy the local equilibrium based on the Gibbs-Thomson equation, iron in the dendrite-structured phase spontaneously dissolved into the zinc bath, resulting in the enrichment of iron in front of the dendrite tip. Through the diffusion boundary layer in front of the dendritic-structured layer, dissolved Fe atoms diffused out and reacted with Zn and small amounts of Al, resulting in the formation of dross particles such as FeZn10Al x ( δ). It was experimentally confirmed that the smaller the difference between the initial iron content in the zinc bath and the iron solubility limit at a given temperature, the lower the number of formed dross particles.

Cast iron cutting with nano TiN and multilayer TiN-CrN coated inserts

Science.gov (United States)

Perucca, M.; Durante, S.; Semmler, U.; Rüger, C.; Fuentes, G. G.; Almandoz, E.

2012-09-01

During the past decade great success has been achieved in the development of duplex and multilayer multi-functional surface systems. Among these surface systems outstanding properties have nanoscale multilayer coatings. Within the framework of the M3-2S project funded in the 7th European Framework Programme, several nanoscale multilayer coatings have been developed and investigated for experimental and industrial validation. This paper shows the performance of TiN and TiN/CrN nanoscale multilayer coatings on WC cutting inserts when machining GJL250 cast iron. The thin films have been deposited by cathodic arc evaporation in an industrial PVD system. The multilayer deposition characteristic and its properties are shown. The inserts have been investigated in systematic cutting experiments of cast iron bars on a turning machine specifically equipped for force measurements, accompanied by wear determination. Furthermore, equivalent experiments have been carried out on an industrial turning unit. Industrial validation criteria have been applied to assess the comparative performance of the coatings. The choice of the material and the machined parts is driven by an interest in automotive applications. The industrial tests show the need to further optimise the multi-scale modelling approach in order to reduce the lead time of the coating development as well as to improve simulation reliability.

Cast iron cutting with nano TiN and multilayer TiN-CrN coated inserts

International Nuclear Information System (INIS)

Perucca, M; Durante, S; Semmler, U; Rüger, C; Fuentes, G G; Almandoz, E

2012-01-01

During the past decade great success has been achieved in the development of duplex and multilayer multi-functional surface systems. Among these surface systems outstanding properties have nanoscale multilayer coatings. Within the framework of the M3-2S project funded in the 7th European Framework Programme, several nanoscale multilayer coatings have been developed and investigated for experimental and industrial validation. This paper shows the performance of TiN and TiN/CrN nanoscale multilayer coatings on WC cutting inserts when machining GJL250 cast iron. The thin films have been deposited by cathodic arc evaporation in an industrial PVD system. The multilayer deposition characteristic and its properties are shown. The inserts have been investigated in systematic cutting experiments of cast iron bars on a turning machine specifically equipped for force measurements, accompanied by wear determination. Furthermore, equivalent experiments have been carried out on an industrial turning unit. Industrial validation criteria have been applied to assess the comparative performance of the coatings. The choice of the material and the machined parts is driven by an interest in automotive applications. The industrial tests show the need to further optimise the multi-scale modelling approach in order to reduce the lead time of the coating development as well as to improve simulation reliability.

High-Performance Corrosion-Resistant Materials: Iron-Based Amorphous-Metal Thermal-Spray Coatings

International Nuclear Information System (INIS)

Farmer, J C; Haslam, J J; Wong, F; Ji, X; Day, S D; Branagan, D J; Marshall, M C; Meacham, B E; Buffa, E J; Blue, C A; Rivard, J K; Beardsley, M B; Weaver, D T; Aprigliano, L F; Kohler, L; Bayles, R; Lemieux, E J; Wolejsza, T M; Martin, F J; Yang, N; Lucadamo, G; Perepezko, J H; Hildal, K; Kaufman, L; Heuer, A H; Ernst, F; Michal, G M; Kahn, H; Lavernia, E J

2004-01-01

The multi-institutional High Performance Corrosion Resistant Materials (HPCRM) Team is cosponsored by the Defense Advanced Projects Agency (DARPA) Defense Science Office (DSO) and the Department of Energy (DOE) Office of Civilian Radioactive Waste Management (OCRWM), and has developed new corrosion-resistant, iron-based amorphous metals that can be applied as coatings with advanced thermal spray technology. Two compositions have corrosion resistance superior to wrought nickel-based Alloy C-22 (UNS No. N06022) in very aggressive environments, including concentrated calcium-chloride brines at elevated temperature. Corrosion costs the Department of Defense billions of dollars every year, with an immense quantity of material in various structures undergoing corrosion. For example, in addition to fluid and seawater piping, ballast tanks, and propulsions systems, approximately 345 million square feet of structure aboard naval ships and crafts require costly corrosion control measures. The use of advanced corrosion-resistant materials to prevent the continuous degradation of this massive surface area would be extremely beneficial. The Fe-based corrosion-resistant, amorphous-metal coatings under development may prove of importance for applications on ships. Such coatings could be used as an ''integral drip shield'' on spent fuel containers, as well as protective coatings that could be applied over welds, thereby preventing exposure to environments that might cause stress corrosion cracking. In the future, such new high-performance iron-based materials could be substituted for more-expensive nickel-based alloys, thereby enabling a reduction in the $58-billion life cycle cost for the long-term storage of the Nation's spent nuclear fuel by tens of percent

Fission product release from HTGR coated microparticles and fuel elements

International Nuclear Information System (INIS)

Gusev, A.A.; Deryugin, A.I.; Lyutikov, R.A.; Chernikov, A.S.

1991-01-01

The article presents the results of the investigation of fission products release from microparticles with UO 2 core and five-layer HII PyC- and SiC base protection layers of TRICO type as well as from spherical fuel elements based thereon. It is shown that relative release of short-lived xenon and crypton from microparticles does not exceed (2-3) 10 -7 . The release of gaseous fission products from fuel elements containing no damaged coated microparticles, is primarily determined by the contamination of matrix graphite with fuel. An analytical dependence is derived, the dependence described the relation between structural parameters of coated microparticles, irradiation conditions and fuel burnup at which depressurization of coated microparticles starts

Influence of dextran coating on the magnetic behaviour of iron oxide nanoparticles

International Nuclear Information System (INIS)

Dutz, Silvio; Andrae, Wilfried; Hergt, Rudolf; Mueller, Robert; Oestreich, Christiane; Schmidt, Christopher; Toepfer, Jorg; Zeisberger, Matthias; Bellemann, Matthias E.

2007-01-01

Magnetic iron oxide nanoparticles with mean diameters in the range from 10 to 30 nm were prepared by modified chemical precipitation routes. The particles were suspended in an aqueous solution by coating of the particles with carboxymethyldextran. A stability against agglomeration was achieved over a period of more than 7 days. In the present investigation, the structural and the magnetic properties of the nanoparticles were investigated. The influence of the dextran shell on the strength of the dipole-dipole interactions between the neighbouring particles was determined by investigation of the remanence behaviour (Henkel plot) of coated as well as of uncoated particles

Some mechanisms for the formation of octopus-shaped iron micro-particles

International Nuclear Information System (INIS)

Bica, Ioan

2004-01-01

Fluid spheres (micro-spheres or/and drops) are formed out of the metallic solid (the carbon steel semi-finished product) in the argon plasma of the transferred electric arc. For short intervals of time, the spheres are at rest with relation to vapors. The movement of the vapors around the spheres is in the same plane. It consists of a movement around a circle combined with the movement produced by a definitely located whirl. The molar concentration of the vapors is small in comparison with the molar density of the mixture formed of vapors and gas. At the intersection of the sphere and the plane of movement of the vapors, distinct stagnation point is formed. They constitute points of the beginning/and end of the current lines. Each current line is a carrier of a vapor cylinder. In time, the cylinder-gas interface reaches points of temperature equal to that of the 'dew point' for iron. On this occasion a liquid membrane is formed. It delimits the vapor-gas mixture from the rest of the gas. Subsequent to the process of diffusion in non-stationary condition, the membrane becomes thicker and no vapors exist inside the tube. Needle-shaped micro-tubes are formed, in liquid phase, around the fluid sphere. By solidification, micro-particles occur, consisting of a central nucleus around which ligaments branch out

Some mechanisms for the formation of octopus-shaped iron micro-particles

Energy Technology Data Exchange (ETDEWEB)

Bica, Ioan E-mail: ibica2@yahoo.com

2004-08-01

Fluid spheres (micro-spheres or/and drops) are formed out of the metallic solid (the carbon steel semi-finished product) in the argon plasma of the transferred electric arc. For short intervals of time, the spheres are at rest with relation to vapors. The movement of the vapors around the spheres is in the same plane. It consists of a movement around a circle combined with the movement produced by a definitely located whirl. The molar concentration of the vapors is small in comparison with the molar density of the mixture formed of vapors and gas. At the intersection of the sphere and the plane of movement of the vapors, distinct stagnation point is formed. They constitute points of the beginning/and end of the current lines. Each current line is a carrier of a vapor cylinder. In time, the cylinder-gas interface reaches points of temperature equal to that of the 'dew point' for iron. On this occasion a liquid membrane is formed. It delimits the vapor-gas mixture from the rest of the gas. Subsequent to the process of diffusion in non-stationary condition, the membrane becomes thicker and no vapors exist inside the tube. Needle-shaped micro-tubes are formed, in liquid phase, around the fluid sphere. By solidification, micro-particles occur, consisting of a central nucleus around which ligaments branch out.

Some mechanisms for the formation of octopus-shaped iron micro-particles

Science.gov (United States)

Bica, Ioan

2004-08-01

Fluid spheres (micro-spheres or/and drops) are formed out of the metallic solid (the carbon steel semi-finished product) in the argon plasma of the transferred electric arc. For short intervals of time, the spheres are at rest with relation to vapors. The movement of the vapors around the spheres is in the same plane. It consists of a movement around a circle combined with the movement produced by a definitely located whirl. The molar concentration of the vapors is small in comparison with the molar density of the mixture formed of vapors and gas. At the intersection of the sphere and the plane of movement of the vapors, distinct stagnation point is formed. They constitute points of the beginning/and end of the current lines. Each current line is a carrier of a vapor cylinder. In time, the cylinder-gas interface reaches points of temperature equal to that of the "dew point" for iron. On this occasion a liquid membrane is formed. It delimits the vapor-gas mixture from the rest of the gas. Subsequent to the process of diffusion in non-stationary condition, the membrane becomes thicker and no vapors exist inside the tube. Needle-shaped micro-tubes are formed, in liquid phase, around the fluid sphere. By solidification, micro-particles occur, consisting of a central nucleus around which ligaments branch out.

Adsorption of Radioactive Chromium onto Iron Oxide Coated Sand

International Nuclear Information System (INIS)

Tadros, N.

2008-01-01

Iron oxide coated sand (IOCS) has been prepared and used as granular sorbent for 51 Cr radionuclide at different and specified concentration Ievels in aqueous solutions of constant ph value. Effect of different parameters such as: ph variation, contact time, 51 Cr ion concentration and variation of temperature on the adsorption of the radionuclide onto IOCS material have been discussed. At high ph value about 9()% of 51 Cr is adsorbed onto IOCS from the aqueous solution, The sorption capability of 51 Cr and the effect of ion concentration on the adsorbitivity have been discussed. Adsorption isotherms of Langmuir and Freundlich were expressed and their adsorption isotherm parameters are tabulated

Wear Resistant Thermal Sprayed Composite Coatings Based on Iron Self-Fluxing Alloy and Recycled Cermet Powders

Directory of Open Access Journals (Sweden)

Heikki SARJAS

2012-03-01

Full Text Available Thermal spray and WC-Co based coatings are widely used in areas subjected to abrasive wear. Commercial  cermet thermal spray powders for HVOF are relatively expensive. Therefore applying these powders in cost-sensitive areas like mining and agriculture are hindered. Nowadays, the use of cheap iron based self-fluxing alloy powders for thermal spray is limited. The aim of this research was to study properties of composite powders based on self-fluxing alloys and recycled cermets and to examine the properties of thermally sprayed (HVOF coatings from composite powders based on iron self-fluxing alloy and recycled cermet powders (Cr3C2-Ni and WC-Co. To estimate the properties of  recycled cermet powders, the sieving analysis, laser granulometry and morphology were conducted. For deposition of coatings High Velocity Oxy-Fuel spray was used. The structure and composition of powders and coatings were estimated by SEM and XRD methods. Abrasive wear performance of coatings was determined and compared with wear resistance of coatings from commercial powders. The wear resistance of thermal sprayed coatings from self-fluxing alloy and recycled cermet powders at abrasion is comparable with wear resistance of coatings from commercial expensive spray powders and may be an alternative in tribological applications in cost-sensitive areas.DOI: http://dx.doi.org/10.5755/j01.ms.18.1.1338

On the effect of pre-oxidation on the nitriding kinetics

DEFF Research Database (Denmark)

Friehling, Peter Bernhard; Somers, Marcel A. J.

2000-01-01

The oxidation of ferritic surfaces prior to gaseous nitriding has been reported to lead to improved uniformity of the compound layer thickness and enhanced nitriding kinetics. The present work considers the nucleation and growth of a model compound layer on pure iron and, using previous...... experimental and theoretical work reported in the literature, puts forward two hypotheses to explain the effects of pre-oxidation on compound layer formation. It is proposed that the nucleation of iron nitrides is enhanced by the presence of an iron-oxide layer and that the growth of an iron-nitride layer...... proceeds faster after pre-oxidation, due to a higher nitrogen content in the part of the compound layer closest to the surface....

Genetics Home Reference: iron-refractory iron deficiency anemia

Science.gov (United States)

... refractory iron deficiency anemia Iron-refractory iron deficiency anemia Printable PDF Open All Close All Enable Javascript ... expand/collapse boxes. Description Iron-refractory iron deficiency anemia is one of many types of anemia , which ...

Humic acid facilitates the transport of ARS-labeled hydroxyapatite nanoparticles in iron oxyhydroxide-coated sand

Science.gov (United States)

Wang, Dengjun; Bradford, Scott A.; Harvey, Ronald W.; Gao, Bin; Cang, Long; Zhou, Dongmei

2012-01-01

Hydroxyapatite nanoparticles (nHAP) have been widely used to remediate soil and wastewater contaminated with metals and radionuclides. However, our understanding of nHAP transport and fate is limited in natural environments that exhibit significant variability in solid and solution chemistry. The transport and retention kinetics of Alizarin red S (ARS)-labeled nHAP were investigated in water-saturated packed columns that encompassed a range of humic acid concentrations (HA, 0–10 mg L–1), fractional surface coverage of iron oxyhydroxide coatings on sand grains (λ, 0–0.75), and pH (6.0–10.5). HA was found to have a marked effect on the electrokinetic properties of ARS-nHAP, and on the transport and retention of ARS-nHAP in granular media. The transport of ARS-nHAP was found to increase with increasing HA concentration because of enhanced colloidal stability and the reduced aggregate size. When HA = 10 mg L–1, greater ARS-nHAP attachment occurred with increasing λ because of increased electrostatic attraction between negatively charged nanoparticles and positively charged iron oxyhydroxides, although alkaline conditions (pH 8.0 and 10.5) reversed the surface charge of the iron oxyhydroxides and therefore decreased deposition. The retention profiles of ARS-nHAP exhibited a hyperexponential shape for all test conditions, suggesting some unfavorable attachment conditions. Retarded breakthrough curves occurred in sands with iron oxyhydroxide coatings because of time-dependent occupation of favorable deposition sites. Consideration of the above effects is necessary to improve remediation efficiency of nHAP for metals and actinides in soils and subsurface environments.

Effect of dietary iron source and iron status on iron bioavailability tests in the rat

International Nuclear Information System (INIS)

Zhang, D.; Hendricks, D.G.; Mahoney, A.W.

1986-01-01

Weanling male rats were made anemic in 7 days by feeding a low iron diet and bleeding. Healthy rats were fed the low iron diet supplemented with ferrous sulfate (29 ppm Fe). Each group was subdivided and fed for 10 days on test diets containing about 29 ppm iron that were formulated with meat:spinach mixtures or meat:soy mixtures to provided 100:0, 75:25, 50:50, 25:75, or 0:100% of the dietary iron from these sources or from a ferrous sulfate diet. After 3 days on the diets all rats were dosed orally with 2 or 5 micro curries of 59 Fe after a 18 hour fast and refeeding for 1.5 hours. Iron status influenced liver iron, carcass iron, liver radio activity and percent of radioactive dose retained. Diet influenced fecal iron and apparent absorption of iron. In iron bioavailability studies assessment methodology and iron status of the test subject greatly influences the estimates of the value of dietary sources of iron

Environmental transformations and ecological effects of iron-based nanoparticles.

Science.gov (United States)

Lei, Cheng; Sun, Yuqing; Tsang, Daniel C W; Lin, Daohui

2018-01-01

The increasing application of iron-based nanoparticles (NPs), especially high concentrations of zero-valent iron nanoparticles (nZVI), has raised concerns regarding their environmental behavior and potential ecological effects. In the environment, iron-based NPs undergo physical, chemical, and/or biological transformations as influenced by environmental factors such as pH, ions, dissolved oxygen, natural organic matter (NOM), and biotas. This review presents recent research advances on environmental transformations of iron-based NPs, and articulates their relationships with the observed toxicities. The type and extent of physical, chemical, and biological transformations, including aggregation, oxidation, and bio-reduction, depend on the properties of NPs and the receiving environment. Toxicities of iron-based NPs to bacteria, algae, fish, and plants are increasingly observed, which are evaluated with a particular focus on the underlying mechanisms. The toxicity of iron-based NPs is a function of their properties, tolerance of test organisms, and environmental conditions. Oxidative stress induced by reactive oxygen species is considered as the primary toxic mechanism of iron-based NPs. Factors influencing the toxicity of iron-based NPs are addressed and environmental transformations play a significant role, for example, surface oxidation or coating by NOM generally lowers the toxicity of nZVI. Research gaps and future directions are suggested with an aim to boost concerted research efforts on environmental transformations and toxicity of iron-based NPs, e.g., toxicity studies of transformed NPs in field, expansion of toxicity endpoints, and roles of laden contaminants and surface coating. This review will enhance our understanding of potential risks of iron-based NPs and proper uses of environmentally benign NPs. Copyright © 2017 Elsevier Ltd. All rights reserved.

Iron absorption in relation to iron status

International Nuclear Information System (INIS)

Magnusson, B.; Bjoern-Rasmussen, E.; Hallberg, L.; Rossander, L.

1981-01-01

The absorption from a 3 mg dose of ferrous iron was measured in 250 male subjects. The absorption was related to the log concentration of serum ferritin in 186 subjects of whom 99 were regular blood donors (r= -0.76), and to bone marrow haemosiderin grading in 52 subjects with varying iron status. The purpose was to try and establish a percentage absorption from such a dose that is representative of subjects who are borderline iron deficient. This information is necessary for food iron absorption studies in order (1) to calculate the absorption of iron from the diet at a given iron status and (2) compare the absorption of iron from different meals studied in different groups of subjects by different investigarors. The results suggest that an absorption of about 40% of a 3 mg reference dose of ferrous iron is given in a fasting state, roughly corresponds to the absorption in borderline-iron-deficient subjects. The results indicate that this 40% absorption value corresponds to a serum ferritin level of 30 μg/l and that food iron absorption in a group of subjects should be expressed preferably as the absorption corresponding to a reference-dose absorption of 45%, or possibly a serum ferritin level of 30 μg/l. (author)

An iron-57 Moessbauer spectroscopic study of titania-supported iron- and iron-iridium catalysts

International Nuclear Information System (INIS)

Berry, F.J.; Jobson, S.

1992-01-01

57 Fe Moessbauer spectroscopy shows that titania-supported iron is reduced by treatment in hydrogen at significantly lower temperatures than corresponding silica- and alumina-supported catalysts. The metallic iron formed under hydrogen at 600deg C is partially converted to carbide by treatment in carbon monoxide and hydrogen. In contrast to its alumina- and silica-supported counterparts, the remainder of the titania-supported iron is unchanged by this gaseous mixture. The 57 Fe Moessbauer spectra of EXAFS show that iron and iridium in the titania-supported iron-iridium catalysts are reduced in hydrogen at even lower temperatures and, after treatment at 600deg C, are predominantly present as the iron-iridium alloy. The treatment of these reduced catalysts in carbon monoxide and hydrogen is shown by Moessbauer spectroscopy and EXAFS to induce the segregation of iron from the iron-iridium alloy and its conversion to iron oxide. (orig.)

Adsorptive removal of manganese, arsenic and iron from groundwater

NARCIS (Netherlands)

Buamah, R.

2009-01-01

Arsenic, manganese and iron in drinking water at concentrations exceeding recommended guideline values pose health risks and aesthetic defects. Batch and pilot experiments on manganese adsorption equilibrium and kinetics using iron-oxide coated sand (IOCS), Aquamandix and other media have been

Preparation and characterization of hydroxyapatite-coated iron oxide particles by spray-drying technique

Directory of Open Access Journals (Sweden)

karina Donadel

2009-06-01

Full Text Available Magnetic particles of iron oxide have been increasingly used in medical diagnosis by magnetic resonance imaging and in cancer therapies involving targeted drug delivery and magnetic hyperthermia. In this study we report the preparation and characterization of iron oxide particles coated with bioceramic hydroxyapatite by spray-drying. The iron oxide magnetic particles (IOMP were coated with hydroxyapatite (HAp by spray-drying using two IOMP/HAp ratios (0.7 and 3.2. The magnetic particles were characterized by way of scanning electronic microscopy, energy dispersive X-ray, X-ray diffraction, Fourier transformed infrared spectroscopy, flame atomic absorption spectrometry,vibrating sample magnetometry and particle size distribution (laser diffraction. The surface morphology of the coated samples is different from that of the iron oxide due to formation of hydroxyapatite coating. From an EDX analysis, it was verified that the surface of the coated magnetic particles is composed only of HAp, while the interior containsiron oxide and a few layers of HAp as expected. The results showed that spray-drying technique is an efficient and relatively inexpensive method for forming spherical particles with a core/shell structure.As partículas de óxido de ferro têm sido extensivamente usadas em diagnósticos médicos como agente de contraste para imagem por ressonância magnética e na terapia do câncer, dentre estas, liberação de fármacos em sitos alvos e hipertermia magnética. Neste estudo nós reportamos a preparação e caracterização de partículas magnéticas de óxido de ferro revestidas com a biocerâmica hidroxiapatita. As partículas magnéticasde óxido de ferro (PMOF foram revestidas com hidroxiapatita por spray-drying usando duas razões PMOF/HAp (0,7 e 3,2. As partículas magnéticas foram caracterizadas por microscopia eletrônica de varredura, energia dispersiva de raios X, difração de raios X, espectroscopia de absorção no infra

Hydraulic characterisation of iron-oxide-coated sand and gravel based on nuclear magnetic resonance relaxation mode analyses

Directory of Open Access Journals (Sweden)

S. Costabel

2018-03-01

Full Text Available The capability of nuclear magnetic resonance (NMR relaxometry to characterise hydraulic properties of iron-oxide-coated sand and gravel was evaluated in a laboratory study. Past studies have shown that the presence of paramagnetic iron oxides and large pores in coarse sand and gravel disturbs the otherwise linear relationship between relaxation time and pore size. Consequently, the commonly applied empirical approaches fail when deriving hydraulic quantities from NMR parameters. Recent research demonstrates that higher relaxation modes must be taken into account to relate the size of a large pore to its NMR relaxation behaviour in the presence of significant paramagnetic impurities at its pore wall. We performed NMR relaxation experiments with water-saturated natural and reworked sands and gravels, coated with natural and synthetic ferric oxides (goethite, ferrihydrite, and show that the impact of the higher relaxation modes increases significantly with increasing iron content. Since the investigated materials exhibit narrow pore size distributions, and can thus be described by a virtual bundle of capillaries with identical apparent pore radius, recently presented inversion approaches allow for estimation of a unique solution yielding the apparent capillary radius from the NMR data. We found the NMR-based apparent radii to correspond well to the effective hydraulic radii estimated from the grain size distributions of the samples for the entire range of observed iron contents. Consequently, they can be used to estimate the hydraulic conductivity using the well-known Kozeny–Carman equation without any calibration that is otherwise necessary when predicting hydraulic conductivities from NMR data. Our future research will focus on the development of relaxation time models that consider pore size distributions. Furthermore, we plan to establish a measurement system based on borehole NMR for localising iron clogging and controlling its remediation

Hydraulic characterisation of iron-oxide-coated sand and gravel based on nuclear magnetic resonance relaxation mode analyses

Science.gov (United States)

Costabel, Stephan; Weidner, Christoph; Müller-Petke, Mike; Houben, Georg

2018-03-01

The capability of nuclear magnetic resonance (NMR) relaxometry to characterise hydraulic properties of iron-oxide-coated sand and gravel was evaluated in a laboratory study. Past studies have shown that the presence of paramagnetic iron oxides and large pores in coarse sand and gravel disturbs the otherwise linear relationship between relaxation time and pore size. Consequently, the commonly applied empirical approaches fail when deriving hydraulic quantities from NMR parameters. Recent research demonstrates that higher relaxation modes must be taken into account to relate the size of a large pore to its NMR relaxation behaviour in the presence of significant paramagnetic impurities at its pore wall. We performed NMR relaxation experiments with water-saturated natural and reworked sands and gravels, coated with natural and synthetic ferric oxides (goethite, ferrihydrite), and show that the impact of the higher relaxation modes increases significantly with increasing iron content. Since the investigated materials exhibit narrow pore size distributions, and can thus be described by a virtual bundle of capillaries with identical apparent pore radius, recently presented inversion approaches allow for estimation of a unique solution yielding the apparent capillary radius from the NMR data. We found the NMR-based apparent radii to correspond well to the effective hydraulic radii estimated from the grain size distributions of the samples for the entire range of observed iron contents. Consequently, they can be used to estimate the hydraulic conductivity using the well-known Kozeny-Carman equation without any calibration that is otherwise necessary when predicting hydraulic conductivities from NMR data. Our future research will focus on the development of relaxation time models that consider pore size distributions. Furthermore, we plan to establish a measurement system based on borehole NMR for localising iron clogging and controlling its remediation in the gravel pack of

Atherosclerotic imaging using 4 types of superparamagnetic iron oxides: New possibilities for mannan-coated particles

Energy Technology Data Exchange (ETDEWEB)

Tsuchiya, Keiko, E-mail: keikot@belle.shiga-medac.jp [Department of Radiology, Shiga University of Medical Science, Setatsukinowa-cho, Otsu, Shiga 520-2192 (Japan); Nitta, Norihisa, E-mail: r34nitta@yahoo.co.jp [Department of Radiology, Shiga University of Medical Science, Setatsukinowa-cho, Otsu, Shiga 520-2192 (Japan); Sonoda, Akinaga, E-mail: akinagasonoda@yahoo.co.jp [Department of Radiology, Shiga University of Medical Science, Setatsukinowa-cho, Otsu, Shiga 520-2192 (Japan); Otani, Hideji, E-mail: otani@belle.shiga-med.ac.jp [Department of Radiology, Shiga University of Medical Science, Setatsukinowa-cho, Otsu, Shiga 520-2192 (Japan); Takahashi, Masashi, E-mail: masashi@belle.shiga-med.ac.jp [Department of Radiology, Shiga University of Medical Science, Setatsukinowa-cho, Otsu, Shiga 520-2192 (Japan); Murata, Kiyoshi, E-mail: murata@belle.shiga-med.ac.jp [Department of Radiology, Shiga University of Medical Science, Setatsukinowa-cho, Otsu, Shiga 520-2192 (Japan); Shiomi, Masashi, E-mail: ieakusm@med.kobe-u.ac.jp [Institute for Experimental Animals, Kobe University School of Medicine, 7-5-1 Kusunoki-cho, Tyuoku, Kobe, Hyogo 650-0017 (Japan); Tabata, Yasuhiko, E-mail: yasuhiko@frontier.kyoto-u.ac.jp [Department of Biomaterials, Institute for Frontier Medical Sciences, Kyoto University, 53 Syogoin-Kawahara-cho, Sakyoku, Kyoto 606-8507 (Japan); Nohara, Satoshi, E-mail: s-nohara@meito-sangyo.co.jp [The Nagoya Research Laboratory, Meito Sangyo Co., Ltd., 25-5 Nishibiwajima-cho, Kiyosu, Aichi 452-0067 (Japan)

2013-11-01

Purpose: We used magnetic resonance imaging (MRI) and histologic techniques to compare the uptake by the rabbit atherosclerotic wall of 4 types of superparamagnetic iron oxide (SPIO) particles, i.e. SPIO, mannan-coated SPIO (M-SPIO), ultrasmall SPIO (USPIO), and mannan-coated USPIO (M-USPIO). Materials and methods: All experimental protocols were approved by our institutional animal experimentation committee. We intravenously injected 12 Watanabe heritable hyperlipidemic rabbits with one of the 4 types of SPIO (0.8 mmol Fe/kg). Two other rabbits served as the control. The rabbits underwent in vivo contrast-enhanced magnetic resonance angiography (MRA) before- and 5 days after these injections; excised aortae were subjected to in vitro MRI. In the in vivo and in vitro studies we assessed the signal intensity of the vessels at identical regions of interest (ROI) and calculated the signal-to-noise ratio (SNR). For histologic assessment we evaluated the iron-positive regions in Prussian blue-stained specimens. Results: There were significant differences in iron-positive regions where M-USPIO > USPIO, M-SPIO > SPIO, USPIO > SPIO (p < 0.05) but not between M-USPIO and M-SPIO. The difference between the pre- and post-injection SNR was significantly greater in rabbits treated with M-USPIO than USPIO and in rabbits injected with M-SPIO than SPIO (p < 0.05). On in vitro MRI scans SNR tended to be lower in M-USPIO- and M-SPIO- than USPIO- and SPIO-treated rabbits (p < 0.1). Conclusion: Histologic and imaging analysis showed that mannan-coated SPIO and USPIO particles were taken up more readily by the atherosclerotic rabbit wall than uncoated SPIO and USPIO.

The kinetics of zinc coating growth on hyper-sandelin steels and ductile cast iron

Directory of Open Access Journals (Sweden)

D. Kopyciński

2007-12-01

Full Text Available The studies aimed at an analysis of the formation and growth kinetics of zinc coating on reactive silicon-killed steels in a zinc bath. The growth kinetics of the produced zinc coatings was evaluated basing on the power-law growth equation. As regards galvanizing of the surface of products, investigation was done for various steel grades and ductile iron taking into account the quality and thickness of coating. It has been proved that the chemical constitution of basis significantly influences the kinetics of growth of the individual phases in a zinc coating. This relationship was evaluated basing on the, so called, silicon and phosphorus equivalent E = (Si+2.5P.103, and coating thickness dependences were obtained.

Iron oxide coating films in soda-lime glass by triboadhesion

Energy Technology Data Exchange (ETDEWEB)

Aguilar, J. O.; Arjona, M. J. [Boulevard Bahia s/n esq. Ignacio Comonfort, Chetumal (Mexico); Rodriguez-Lelis, J. M. [Interior Internado Palmira s/n, Cuernavaca, Morelos (Mexico)

2009-04-15

In the triboadhesion process the coating material is passed through a rotating cotton mop and the substrate to be coated. The cotton mop rotates at high velocity and exerts pressure on the surface of the substrate. The combined effect of pressure and velocity of the coating mop on the substrate increases its temperature close to the melting point, allowing deposition and diffusion of the coating material within the substrate. After it is deposited, its particles are embedded within the base material forming a thin film composite. The amount of the coating material deposited on the substrate has its maximum at the surface and then decreases as a function of the local temperature within the base material. Bearing this in mind, in the present work, triboadhesion is employed to deposit iron oxide in a substrate of soda-lime glass, with the purpose of determining the feasibility of using this technique for solar control coatings. It was found, through electronic scan microscopy, that a composite material film is formed following the coating direction. Reflectance and transmittance tests were carried out on the glass samples. A 20% difference was found in the visible spectral region (VIS), and a reduction between 10 and 20% in the Near Infrared Region (NIR). These results showed that the triboadhesion is a promising technique for the application of thin films for solar control or solar cells

Iron oxide coating films in soda-lime glass by triboadhesion

International Nuclear Information System (INIS)

Aguilar, J. O.; Arjona, M. J.; Rodriguez-Lelis, J. M.

2009-01-01

In the triboadhesion process the coating material is passed through a rotating cotton mop and the substrate to be coated. The cotton mop rotates at high velocity and exerts pressure on the surface of the substrate. The combined effect of pressure and velocity of the coating mop on the substrate increases its temperature close to the melting point, allowing deposition and diffusion of the coating material within the substrate. After it is deposited, its particles are embedded within the base material forming a thin film composite. The amount of the coating material deposited on the substrate has its maximum at the surface and then decreases as a function of the local temperature within the base material. Bearing this in mind, in the present work, triboadhesion is employed to deposit iron oxide in a substrate of soda-lime glass, with the purpose of determining the feasibility of using this technique for solar control coatings. It was found, through electronic scan microscopy, that a composite material film is formed following the coating direction. Reflectance and transmittance tests were carried out on the glass samples. A 20% difference was found in the visible spectral region (VIS), and a reduction between 10 and 20% in the Near Infrared Region (NIR). These results showed that the triboadhesion is a promising technique for the application of thin films for solar control or solar cells

Higher iron bioavailability of a human-like collagen iron complex.

Science.gov (United States)

Zhu, Chenhui; Yang, Fan; Fan, Daidi; Wang, Ya; Yu, Yuanyuan

2017-07-01

Iron deficiency remains a public health problem around the world due to low iron intake and/or bioavailability. FeSO 4 , ferrous succinate, and ferrous glycinate chelate are rich in iron but have poor bioavailability. To solve the problem of iron deficiency, following previous research studies, a thiolated human-like collagen-ironcomplex supplement with a high iron content was prepared in an anaerobic workstation. In addition, cell viability tests were evaluated after conducting an MTT assay, and a quantitative analysis of the thiolated human-like collagen-iron digesta samples was performed using the SDS-PAGE method coupled with gel filtration chromatography. The iron bioavailability was assessed using Caco-2 cell monolayers and iron-deficiency anemia mice models. The results showed that (1) one mole of thiolated human-like collagen-iron possessed approximately 35.34 moles of iron; (2) thiolated human-like collagen-iron did not exhibit cytotoxity and (3) thiolated human-like collagen- iron digesta samples had higher bioavailability than other iron supplements, including FeSO 4 , ferrous succinate, ferrous glycine chelate and thiolated human-like collagen-Fe iron. Finally, the iron bioavailability was significantly enhanced by vitamin C. These results indicated that thiolated human-like collagen-iron is a promising iron supplement for use in the future.

Arsenic removal from water using iron-coated seaweeds.

Science.gov (United States)

Vieira, Bárbara R C; Pintor, Ariana M A; Boaventura, Rui A R; Botelho, Cidália M S; Santos, Sílvia C R

2017-05-01

Arsenic is a semi-metal element that can enter in water bodies and drinking water supplies from natural deposits and from mining, industrial and agricultural practices. The aim of the present work was to propose an alternative process for removing As from water, based on adsorption on a brown seaweed (Sargassum muticum), after a simple and inexpensive treatment: coating with iron-oxy (hydroxides). Adsorption equilibrium and kinetics were studied and modeled in terms of As oxidation state (III and V), pH and initial adsorbate concentration. Maximum adsorption capacities of 4.2 mg/g and 7.3 mg/g were obtained at pH 7 and 20 °C for arsenite and arsenate, respectively. When arsenite was used as adsorbate, experimental evidences pointed to the occurrence of redox reactions involving As(III) oxidation to As(V) and Fe(III) reduction to Fe(II), with As(V) uptake by the adsorbent. The proposed adsorption mechanism was then based on the assumption that arsenate was the adsorbed arsenic species. The most relevant drawback found in the present work was the considerable leaching of iron to the solution. Arsenite removal from a mining-influenced water by adsorption plus precipitation was studied and compared to a traditional process of coagulation/flocculation. Both kinds of treatment provided practically 100% of arsenite removal from the contaminated water, leading at best in 12.9 μg/L As after the adsorption and precipitation assays and 14.2 μg/L after the coagulation/flocculation process. Copyright © 2017 Elsevier Ltd. All rights reserved.

Electrochemical synthesis and spectroscopic characterization of poly(N-phenylpyrrole coatings in an organic medium on iron and platinum electrodes

Directory of Open Access Journals (Sweden)

A.K.D. Diaw

2008-12-01

Full Text Available The electrochemical synthesis of poly(N-phenylpyrrole film was achieved on pretreated iron and platinum electrodes in acetonitrile solutions containing 0.1 M N-phenylpyrrole as the monomer and 0.1 M tetrabutylammonium trifluoromethane sulfonate (Bu4NCF3SO3 as the supporting-salt. The results showed that a surface treatment by 10 % aqueous nitric acid inhibits iron dissolution without preventing the N-phenylpyrrole oxidation. Very strongly adherent films were obtained at constant-potential, constant-current and cyclic voltammetry. XPS measurements, infrared (FT-IR and electronic absorption (UV-vis spectroscopies were used to characterize the iron and platinum-coated electrodes. Finally the anticorrosion properties of the PΦP film were evidenced.

Identification of second harmonic optical effects from vaccine coated gold microparticles

International Nuclear Information System (INIS)

Jumah, N A; Ameer-Beg, S M; White, N S; Prasad, K V R; Bellhouse, B J

2004-01-01

This study investigates the optical effects observed from uncoated and protein vaccine coated gold microparticles while imaging with two-photon excitation in the Mie scattering regime. When observed with time correlated single photon counting fluorescence lifetime microscopy, the emission from the gold microparticles appeared as an intense instrument-limited temporal response. The intensity of the emission showed a second-order dependence on the laser power and frequency doubling of the emitted light was observed for fundamental light between 890 and 970 nm. The optical effect was attributed to two-photon induced second harmonic generation. The vaccine coated gold microparticles had a much weaker second harmonic signal than the uncoated gold microparticles. Chemical analysis of the surface of the gold microparticles revealed that the vaccine coating decreases the surface charge thereby diminishing the observed second harmonic signal. These optical properties can be exploited to identify both the location of the protein vaccine coating as well as the gold microparticles in vitro and potentially to investigate the vaccine delivery kinetics in vivo

Iron

Science.gov (United States)

Iron is a mineral that our bodies need for many functions. For example, iron is part of hemoglobin, a protein which carries ... It helps our muscles store and use oxygen. Iron is also part of many other proteins and ...

A cascade of iron-containing proteins governs the genetic iron starvation response to promote iron uptake and inhibit iron storage in fission yeast.

Directory of Open Access Journals (Sweden)

Javier Encinar del Dedo

2015-03-01

Full Text Available Iron is an essential cofactor, but it is also toxic at high levels. In Schizosaccharomyces pombe, the sensor glutaredoxin Grx4 guides the activity of the repressors Php4 and Fep1 to mediate a complex transcriptional response to iron deprivation: activation of Php4 and inactivation of Fep1 leads to inhibition of iron usage/storage, and to promotion of iron import, respectively. However, the molecular events ruling the activity of this double-branched pathway remained elusive. We show here that Grx4 incorporates a glutathione-containing iron-sulfur cluster, alone or forming a heterodimer with the BolA-like protein Fra2. Our genetic study demonstrates that Grx4-Fra2, but not Fep1 nor Php4, participates not only in iron starvation signaling but also in iron-related aerobic metabolism. Iron-containing Grx4 binds and inactivates the Php4 repressor; upon iron deprivation, the cluster in Grx4 is probably disassembled, the proteins dissociate, and Php4 accumulates at the nucleus and represses iron consumption genes. Fep1 is also an iron-containing protein, and the tightly bound iron is required for transcriptional repression. Our data suggest that the cluster-containing Grx4-Fra2 heterodimer constitutively binds to Fep1, and upon iron deprivation the disassembly of the iron cluster between Grx4 and Fra2 promotes reverse metal transfer from Fep1 to Grx4-Fra2, and de-repression of iron-import genes. Our genetic and biochemical study demonstrates that the glutaredoxin Grx4 independently governs the Php4 and Fep1 repressors through metal transfer. Whereas iron loss from Grx4 seems to be sufficient to release Php4 and allow its nuclear accumulation, total or partial disassembly of the Grx4-Fra2 cluster actively participates in iron-containing Fep1 activation by sequestering its iron and decreasing its interaction with promoters.

Iron oxyhydroxide mineralization on microbial extracellular polysaccharides

Energy Technology Data Exchange (ETDEWEB)

Chan, Clara S.; Fakra, Sirine C.; Edwards, David C.; Emerson, David; Banfield, Jillian F.

2010-06-22

Iron biominerals can form in neutral pH microaerophilic environments where microbes both catalyze iron oxidation and create polymers that localize mineral precipitation. In order to classify the microbial polymers that influence FeOOH mineralogy, we studied the organic and mineral components of biominerals using scanning transmission X-ray microscopy (STXM), micro X-ray fluorescence ({mu}XRF) microscopy, and high-resolution transmission electron microscopy (HRTEM). We focused on iron microbial mat samples from a creek and abandoned mine; these samples are dominated by iron oxyhydroxide-coated structures with sheath, stalk, and filament morphologies. In addition, we characterized the mineralized products of an iron-oxidizing, stalk-forming bacterial culture isolated from the mine. In both natural and cultured samples, microbial polymers were found to be acidic polysaccharides with carboxyl functional groups, strongly spatially correlated with iron oxyhydroxide distribution patterns. Organic fibrils collect FeOOH and control its recrystallization, in some cases resulting in oriented crystals with high aspect ratios. The impact of polymers is particularly pronounced as the materials age. Synthesis experiments designed to mimic the biomineralization processes show that the polysaccharide carboxyl groups bind dissolved iron strongly but release it as mineralization proceeds. Our results suggest that carboxyl groups of acidic polysaccharides are produced by different microorganisms to create a wide range of iron oxyhydroxide biomineral structures. The intimate and potentially long-term association controls the crystal growth, phase, and reactivity of iron oxyhydroxide nanoparticles in natural systems.

Dietary iron intake, iron status, and gestational diabetes.

Science.gov (United States)

Zhang, Cuilin; Rawal, Shristi

2017-12-01

Pregnant women are particularly vulnerable to iron deficiency and related adverse pregnancy outcomes and, as such, are routinely recommended for iron supplementation. Emerging evidence from both animal and population-based studies, however, has raised potential concerns because significant associations have been observed between greater iron stores and disturbances in glucose metabolism, including increased risk of type 2 diabetes among nonpregnant individuals. Yet, the evidence is uncertain regarding the role of iron in the development of gestational diabetes mellitus (GDM), a common pregnancy complication which has short-term and long-term adverse health ramifications for both women and their children. In this review, we critically and systematically evaluate available data examining the risk of GDM associated with dietary iron, iron supplementation, and iron status as measured by blood concentrations of several indicators. We also discuss major methodologic concerns regarding the available epidemiologic studies on iron and GDM. © 2017 American Society for Nutrition.

Studies on the pathogenesis in iron deficiency anemia Part 1. Urinary iron excretion in iron deficiency anemia patients and rats in various iron states

OpenAIRE

中西,徳彦

1991-01-01

In the "iron excretion test" , urinary iron excretion after injection of saccharated iron oxide has been reported to be accelerated in relapsing idiopathic iron deficiency anemia. To determine the relevance of urinary iron excretion to clinical factors other than iron metabolism, 15 clinical parameters were evaluated. The serum creatinine level was positively and the serum albumin level was negatively correlated with urinary iron excretion, showing coefficients of r＝0.97,－0.86 respectively, a...

Magnetoelectric behavior of carbonyl iron mixed Mn oxide-coated ferrite nanoparticles

Science.gov (United States)

Ahad, Faris B. Abdul; Lee, Shang-Fan; Hung, Dung-Shing; Yao, Yeong-Der; Yang, Ruey-Bin; Lin, Chung-Kwei; Tsay, Chien-Yie

2010-05-01

The dielectric and magnetic properties of manganese oxide-coated Fe3O4 nanoparticles (NPs) were measured by the cavity perturbation method at x-band microwave frequencies ranging from 7-12.5 GHz with controlled external magnetic field up to 2.2 kOe at room temperature. Different ratios (5%, 10%, and 20% by weight) of coated NPs were prepared by sol-gel method then mixed with carbonyl iron powder in epoxy matrix. The saturation magnetization is inversely proportional to the NPs ratio in the mixture between 150 and 180 emu/g. The real part of the permittivity decreased with increasing NPs concentration, but the permittivity change by magnetic field increased. The tunability behavior is explained by insulator-ferromagnetic interface magnetoelectricity and the large surface volume ratio for the NPs.

Corrosion monitoring of iron, protected by an organic coating, with the aid of impedance measurements

International Nuclear Information System (INIS)

Hubrecht, J.; Piens, M.; Vereecken, J.

1984-01-01

The ac impedance measurement has proved to be a useful electrochemical technique for mainly qualitative studies of electrochemical and corrosion systems. Even for complicated systems such as coated metals in corrosive environments this technique has been used with success. The system chosen for the present study is an ARMCO iron plate, coated with a SrCrO 4 -pigmented styrene acrylic polymer, and immersed for several weeks in an aqueous NaCl solution. Impedance measurements analyze a system under test into its constituting phenomena. The dependence of system parameters on coating layer thickness, NaCl concentration, and pigmentation of the coating during the immersion time provides insight into the corrosion and protection mechanisms at the coating/metal interface, besides the behavior of the coating itself

Removal of dissolved heavy metals from pre-settled stormwater runoff by iron-oxide coated sand (IOCS)

DEFF Research Database (Denmark)

Møller, J.; Ledin, Anna; Mikkelsen, Peter Steen

2002-01-01

(Pb=20, Cu=40, Zn=110, and Cr=15 ppb). Column experiments were conducted to test the influence of the infiltration rate (1 or 3 m/h) and the type of iron(hydr)oxide mineral (amorphous ferrihydrite and goethite coated sand). The results show that at least 90% of lead, copper and zinc can be removed......Sorption to iron-oxide coated sand (IOCS) is a promosing technology for removal of the dissolved heavy metal fraction in stormwater runoff. The development of a new technology is necessary since studies of stormwater runoff from traffic areas indicate that an oil separator and detention pond may...... by IOCS after 480 pore volumes. Control columns with uncoated filter sand show that lead, copper and zinc were removed with >95%, 35% and 5%, respectively. The removal of the negative metaloxy-ion, CrO4-3 was insignificant in both IOCS and sand columns at pH=7.7. Destruction of the columns after...

Iron from Zealandic bog iron ore -

DEFF Research Database (Denmark)

Lyngstrøm, Henriette Syrach

2011-01-01

og geologiske materiale, metallurgiske analyser og eksperimentel arkæologiske forsøg - konturerne af en jernproduktion med udgangspunkt i den sjællandske myremalm. The frequent application by archaeologists of Werner Christensen’s distribution map for the occurrence of bog iron ore in Denmark (1966...... are sketched of iron production based on bog iron ore from Zealand....

Ceramic port shields cast in an iron engine head

Science.gov (United States)

Hakim, Nabil S.; Groeneweg, Mark A.

1989-01-01

Silicon nitride exhaust and intake port shields have been successfully cast into a gray iron cylinder head of a heavy duty diesel single cylinder research engine. Careful design considerations, finite element, and probability of survival analyses indicated viability of the design. Foundry experience, NDE, and failure investigations are reported.

Iron-dependent formation of reactive oxygen species and glutathione depletion after accumulation of magnetic iron oxide nanoparticles by oligodendroglial cells

International Nuclear Information System (INIS)

Hohnholt, Michaela C.; Dringen, Ralf

2011-01-01

Magnetic iron oxide nanoparticles (IONP) are currently used for various neurobiological applications. To investigate the consequences of a treatment of brain cells with such particles, we have applied dimercaptosuccinate (DMSA)-coated IONP that had an average hydrodynamic diameter of 60 nm to oligodendroglial OLN-93 cells. After exposure to 4 mM iron applied as DMSA–IONP, these cells increased their total specific iron content within 8 h 600-fold from 7 to 4,200 nmol/mg cellular protein. The strong iron accumulation was accompanied by a change in cell morphology, although the cell viability was not compromized. DMSA–IONP treatment caused a concentration-dependent increase in the iron-dependent formation of reactive oxygen species and a decrease in the specific content of the cellular antioxidative tripeptide glutathione. During a 16 h recovery phase in IONP-free culture medium following exposure to DMSA–IONP, OLN-93 cells maintained their high iron content and replenished their cellular glutathione content. These data demonstrate that viable OLN-93 cells have a remarkable potential to deal successfully with the consequences of an accumulation of large amounts of iron after exposure to DMSA–IONP.

Response to parenteral iron therapy distinguish unexplained refractory iron deficiency anemia from iron-refractory iron deficiency anemia.

Science.gov (United States)

Akin, M; Sarbay, H; Guler, S; Balci, Y I; Polat, A

2016-04-01

We evaluated that response to parenteral iron therapy could be helpful in distinguishing the types of iron deficiency anemia. This study analyzed responses to IV iron sucrose therapy of 15 children with unexplained refractory iron deficiency anemia (URIDA). We compared the results at diagnosis, 6 weeks and 6 months after the therapy. Results were compared with responses of 11 patients' results with iron-refractory iron deficiency anemia (IRIDA) from our previous study. Six weeks after the start of treatment, ferritin, MCV, MCH and Hb values were in normal range in 10 patients. The increase in Hb, MCH, MCV, and ferritin values ranged 2.6-3.5 g/dL, 1.7-4.2 pg, 2-9 fL, and 13-25 ng/mL, respectively. In five patients, Hb, MCH, and MCV mean (range) values [11.2 g/dL (11-12.2), 24.5 pg (24-25.6), and 67 fL (65-70)] were nearly normal but ferritin mean (range) values [9.8 ng/mL (8-11)] were below normal. Six weeks after the start of treatment, Hb, MCH, MCV and ferritin values of patients with IRIDA were increased. The increase in Hb, MCH, MCV, and ferritin values ranged 0.8-2.7 g/dL, 1.7-4.2 pg, 2-9 fL, and 13-25 ng/mL, respectively. IRIDA is only partially responsive to parenteral iron supplementation. In conclusion, this study demonstrated that the response to intravenous iron therapy for the URIDA cases improved blood parameters more effectively than hereditary IRIDA. Response to parenteral iron therapy would be helpful to distinguish unexplained refractory IDA from hereditary IRIDA for clinicians who do not have access to hepcidin or TMPRS6 mutation analysis. © 2016 John Wiley & Sons Ltd.

Formation of coatings from a liquid phase on the surface of iron-base alloys

Directory of Open Access Journals (Sweden)

A. Tatarek

2008-12-01

Full Text Available The study discloses the present state of the art regarding the technology and investigations of the phenomena that take place during the formation and growth of aluminum and zinc coatings hot-dip formed on iron products. In its cognitive aspect, the study offers an in-depth analysis of the partial processes that proceed in metal bath at the solid body – liquid metal interface. It is expected that the present study will help in a more detailed description of the respective phenomena and in full explanation of the mechanism of the coating growth, taking as an example the growth of aluminum coatings. The obtained results can serve as a background for some general conclusions regarding the thickness evolution process in other hot-dip coatings.

Iron coated pottery granules for arsenic removal from drinking water.

Science.gov (United States)

Dong, Liangjie; Zinin, Pavel V; Cowen, James P; Ming, Li Chung

2009-09-15

A new media, iron coated pottery granules (ICPG) has been developed for As removal from drinking water. ICPG is a solid phase media that produces a stable Fe-Si surface complex for arsenic adsorption. Scanning electron microscopy (SEM) was used to document the physical attributes (grain size, pore size and distribution, surface roughness) of the ICPG media. Several advantages of the ICPG media such as (a) its granular structure, (b) its ability to absorb As via the F(0) coating on the granules' surface; (c) the inexpensive preparation process for the media from clay material make ICPG media a highly effective media for removing arsenic at normal pH. A column filtration test demonstrated that within the stability region (flow rate lower than 15L/h, EBCT >3 min), the concentration of As in the influent was always lower than 50 microg/L. The 2-week system ability test showed that the media consistently removed arsenic from test water to below the 5 microg/L level. The average removal efficiencies for total arsenic, As(III), and As(V) for a 2-week test period were 98%, 97%, and 99%, respectively, at an average flow rate of 4.1L/h and normal pH. Measurements of the Freundlich and Langmuir isotherms at normal pH show that the Freundlich constants of the ICPG are very close to those of ferric hydroxide, nanoscale zero-valent iron and much higher than those of nanocrystalline titanium dioxide. The parameter 1/n is smaller than 0.55 indicating a favorable adsorption process [K. Hristovski, A. Baumgardner, P. Westerhoff, Selecting metal oxide nanomaterials for arsenic removal in fixed bed columns: from nanopowders to aggregated nanoparticle media, J. Hazard. Mater. 147 (2007) 265-274]. The maximum adsorption capacity (q(e)) of the ICPG from the Langmuir isotherm is very close to that of nanoscale zero-valent indicating that zero-valent iron is involved in the process of the As removal from the water. The results of the toxicity characteristic leaching procedure (TCLP

Iron coated pottery granules for arsenic removal from drinking water

International Nuclear Information System (INIS)

Dong Liangjie; Zinin, Pavel V.; Cowen, James P.; Ming, Li Chung

2009-01-01

A new media, iron coated pottery granules (ICPG) has been developed for As removal from drinking water. ICPG is a solid phase media that produces a stable Fe-Si surface complex for arsenic adsorption. Scanning electron microscopy (SEM) was used to document the physical attributes (grain size, pore size and distribution, surface roughness) of the ICPG media. Several advantages of the ICPG media such as (a) its granular structure, (b) its ability to absorb As via the F(0) coating on the granules' surface; (c) the inexpensive preparation process for the media from clay material make ICPG media a highly effective media for removing arsenic at normal pH. A column filtration test demonstrated that within the stability region (flow rate lower than 15 L/h, EBCT >3 min), the concentration of As in the influent was always lower than 50 μg/L. The 2-week system ability test showed that the media consistently removed arsenic from test water to below the 5 μg/L level. The average removal efficiencies for total arsenic, As(III), and As(V) for a 2-week test period were 98%, 97%, and 99%, respectively, at an average flow rate of 4.1 L/h and normal pH. Measurements of the Freundlich and Langmuir isotherms at normal pH show that the Freundlich constants of the ICPG are very close to those of ferric hydroxide, nanoscale zero-valent iron and much higher than those of nanocrystalline titanium dioxide. The parameter 1/n is smaller than 0.55 indicating a favorable adsorption process [K. Hristovski, A. Baumgardner, P. Westerhoff, Selecting metal oxide nanomaterials for arsenic removal in fixed bed columns: from nanopowders to aggregated nanoparticle media, J. Hazard. Mater. 147 (2007) 265-274]. The maximum adsorption capacity (q e ) of the ICPG from the Langmuir isotherm is very close to that of nanoscale zero-valent indicating that zero-valent iron is involved in the process of the As removal from the water. The results of the toxicity characteristic leaching procedure (TCLP) analysis

Optical Properties of Fe3O4 Thin Films Prepared from the Iron Sand by Spin Coating Method

Science.gov (United States)

Yulfriska, N.; Rianto, D.; Murti, F.; Darvina, Y.; Ramli, R.

2018-04-01

Research on magnetic oxide is growing very rapidly. This magnetic oxide can be found in nature that is in iron sand. One of the beaches in Sumatera Barat containing iron sand is Tiram Beach, Padang Pariaman District, Sumatera Barat. The content of iron sand is generally in the form of magnetic minerals such as magnetite, hematite, and maghemit. Magnetite has superior properties that can be developed into thin films. The purpose of this research is to investigate the optical properties of transmittance, absorbance, reflectance and energy gap from Fe3O4 thin films. This type of research is an experimental research. The iron sand obtained from nature is first purified using a permanent magnet, then made in nanoparticle size using HEM-E3D with milling time for 30 hours. After that, the process of making thin film with sol-gel spin coating method. In this research, variation of rotation speed from spin coating is 1000 rpm, 2000 rpm and 3000 rpm. Based on XRD results indicated that the iron sand of Tiram beach contains magnetite minerals and the SEM results show that the thickness of the thin films formed is 25μm, 24μm and 11μm. The characterization tool used for characterizing optical properties is the UV-VIS Spectrophotometer. So it can be concluded that the greater the speed of rotation the thickness of the thin layer will be smaller, resulting in the transmittance and reflectance will be greater, while the absorbance will be smaller. Energy gap obtained from this research is 3,75eV, 3,75eV and 3,74eV. So the average energy gap obtained is 3,75eV.

Iron isomaltoside 1000: a new intravenous iron for treating iron deficiency in chronic kidney disease

DEFF Research Database (Denmark)

Wikström, Björn; Bhandari, Sunil; Barany, Peter

2011-01-01

Patients with chronic kidney disease (CKD) often suffer from iron deficiency anemia necessitating treatment with intravenous iron. This study was designed to assess the safety of iron isomaltoside 1000 (Monofer) in CKD patients. The secondary objective was to assess its effect on iron deficiency...... anemia....

The Effect Of Local Coal And Smelting Sponge Iron On Iron Content Of Pig Iron

Science.gov (United States)

Oediyani, Soesaptri; Juwita Sari, Pramita; Hadi P, Djoko

2018-03-01

The new regulation on mineral resources was announced by Ministry of Energy and Mineral resources (ESDM) of Indonesia at 2014 which it called Permen ESDM No 1/2014. Therefore, this research was conducted to add the value of local iron ores by using smelting technology. The objective of the research is to produce pig iron that meet the requirement of the new regulation of mineral resources such as 90% Fe. First, iron ores and coal mixed together with lime as a flux, then smelted in a Electric Arc Furnace at 1800°C. The process variables are (1; 1.25; 1.5; 1.75; 2.0) and the composition of coal (0.8%, 1.6%, 3.0%). The type of coal that used in this research was bituminous coal from Kalimantan and also the iron ores from Kalimantan. The products of the smelting technology are Pig iron and slag. Both pig iron and slag then analyzed by SEM-EDS to measure the iron content. The result shows that the maximum iron content on pig iron is about 95.04% meanwhile the minimum iron content on slag is about 3.66%. This result achieved at 1.6% coal and 2.0.

Profile analysis of microparticles

International Nuclear Information System (INIS)

Konarski, P.; Iwanejko, I.; Mierzejewska, A.

2001-01-01

Depth resolved analyses of several types of microparticles are presented. Particles for secondary ion mass spectrometry (SIMS) depth profile analysis were collected in the working environment of glass plant, steelworks and welding station using eight-stage cascade impactor with particle size range of 0.3 μm to 15 μm. Ion beam sputtering and sample rotation technique allowed to describe morphology i.e. the elemental structure of collected sub-micrometer particles. Also model particles Iriodin 221 (Merck) were depth profiled. The core-shell structure is found for all types of investigated particles. Steelworks particles consist mainly of iron and manganese cores. At the shells of these microparticles: lead, chlorine and fluorine are found. The particles collected in the glass-works consist mainly of lead-zirconium glass cores covered by carbon and copper. Stainless-steel welding particles compose of iron, manganese and chromium cores covered by a shell rich in carbon, chlorine and fluorine. Sample rotation technique applied in SIMS appears to be an effective tool for environmental microparticle morphology studies

Thermodynamics, kinetics and process control of nitriding

DEFF Research Database (Denmark)

Mittemeijer, Eric J.; Somers, Marcel A. J.

1999-01-01

As a prerequisite for predictability of properties obtained by a nitriding treatment of iron-based workpieces, the relation between the process parameters and the composition and structure of the surface layer produced must be known. At present (even) the description of thermodynamic equilibrium...... of pure iron-nitrogen phases has not been achieved fully. It has been shown that taking into account ordering of nitrogen in the epsilon and gamma' iron-nitride phases, leads to an improved understanding of the Fe-N phase diagram. Although thermodynamics indicate the state the system strives for......, the nitriding result is determined largely by the kinetics of the process. The nitriding kinetics have been shown to be characterised by the occurring local near-equilibria and stationary states at surfaces and interfaces, and the diffusion coefficient of nitrogen in the various phases, for which new data have...

Iron biomineralization by anaerobic neutrophilic iron-oxidizing bacteria

DEFF Research Database (Denmark)

Miot, Jennyfer; Benzerara, Karim; Morin, Guillaume

2009-01-01

Minerals formed by bio-oxidation of ferrous iron (Fe(II)) at neutral pH, their association with bacterial ultrastructures as well as their impact on the metabolism of iron-oxidizing bacteria remain poorly understood. Here, we investigated iron biomineralization by the anaerobic nitrate-dependent ......Minerals formed by bio-oxidation of ferrous iron (Fe(II)) at neutral pH, their association with bacterial ultrastructures as well as their impact on the metabolism of iron-oxidizing bacteria remain poorly understood. Here, we investigated iron biomineralization by the anaerobic nitrate...... precipitation in the periplasm (in a few tens of minutes), followed by the formation of surface-bound globules. Moreover, we frequently observed an asymmetric mineral thickening at the cell poles. In parallel, the evolution of iron oxidation was quantified by STXM: iron both contained in the bacteria...... and in the extracellular precipitates reached complete oxidation within 6 days. While a progressive oxidation of Fe in the bacteria and in the medium could be observed, spatial redox (oxido-reduction state) heterogeneities were detected at the cell poles and in the extracellular precipitates after 1 day. All...

Chemical synthesis and characterization of hollow dopamine coated, pentagonal and flower shaped magnetic iron oxide nanoparticles

Science.gov (United States)

Riasat, Rabia; Kaynat, Sumbal

2018-04-01

Iron oxide nanoparticles have gained attention recently in the field of nanoscience and technology due to their unique physicochemical properties. We hereby chemically synthesized novel pentagonal flower shaped iron oxide nanoparticles by thermal decomposition of iron penta-carbonyl in a two way annealing process. Controlled oxidation by acid etching was performed for these nanoparticles. At first 13 nm core shell nanoparticles of iron oxide (Fe/Fe3O4) were synthesized at 120°C annealing temperature that act as template material. The core shell nanoparticles then converted into porous hollow core shell nanoparticles (PH Fe/ Fe3O4) in a two way annealing process of heating, first at 100°C then at 250°C and heating rate of 5°C was kept constant throughout the reaction time. X-Ray diffraction (XRD) was done for the phase confirmation of as synthesized nanoparticles. Transmission electron microscopy (TEM) and higher resolution transmission electron microscopy (HRTEM) clearly shows the flower like nanoparticles that are approx. 16 nm-18 nm in size having the 4-5 nm core of Fe and 1-2 nm of the pores in the shell while the cavity between the shell and core is about 2 nm and the shell is 4-5 nm in diameter according to the TEM micrographs. The as prepared nanoparticles were then surface functionalized by dopamine polymer to make them water dispersible. Fourier transform Infrared spectroscopy confirmed the dopamine coating on the nanoparticles and the magnetic saturation of 38 emu/g of nanoparticles was analyzed by vibrating sample magnetometer (VSM). Magnetic saturation persists in the dopamine coated nanoparticles. These nanoparticles were surface functionalized with dopamine and show dispersity in the aqueous media and can further be exploited in many nano-biotechnological applications including target specific therapeutic applications for several diseases.

46 CFR 56.60-10 - Cast iron and malleable iron.

Science.gov (United States)

2010-10-01

... 46 Shipping 2 2010-10-01 2010-10-01 false Cast iron and malleable iron. 56.60-10 Section 56.60-10... APPURTENANCES Materials § 56.60-10 Cast iron and malleable iron. (a) The low ductility of cast iron and malleable iron should be recognized and the use of these metals where shock loading may occur should be...

Analysis of Crystal Structure of Fe3O4 Thin Films Based on Iron Sand Growth by Spin Coating Method

Science.gov (United States)

Rianto, D.; Yulfriska, N.; Murti, F.; Hidayati, H.; Ramli, R.

2018-04-01

Recently, iron sand used as one of base materials in the steel industry. However, the content of iron sand can be used as starting materials in sensor technology in the form of thin films. In this paper, we report the analysis of crystal structure of magnetite thin film based on iron sand from Tiram’s Beach. The magnetic content of sand separated by a permanent magnet, then it was milled at 30 hours milling time. In order to increase the purity of magnetite, it washed after milling using aquades under magnetic separation by a magnet permanent. The thin film has been prepared using iron (III) nitrate by sol–gel technique. The precursor is resulted by dissolving magnetite in oxalic acid and nitric acid. Then, solution of iron (III) nitrate dissolved in ethylene glycol was applied on glass substrates by spin coating. The X-Ray Diffraction is operated thin film characterization. The structure of magnetite has been studied based on X-Ray Peaks that correspond to magnetite content of thin films.

Photoactive nanocomplex formed from chlorophyll assembly on TMA-coated iron oxide nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Barbaros, Sibel; Meray, Zeynep; Tecim, Tuğba; Genç, Rükan, E-mail: rukangnc@gmail.com [Mersin University, Functional Nanomaterials Laboratory, Chemical Engineering Department, Engineering Faculty (Turkey)

2016-07-15

In this study, hierarchical self-assembly of photocatalytic nanodisks through non-covalent interactions between spinach-extracted chlorophyll molecules and trimethylammonium hydroxide-coated magnetic iron oxide nanoparticles was discussed. Combination of chlorophyll molecules with iron oxide nanoparticles generated an alteration in light absorption at both visible and near-IR region with accompanying enhancement in fluorescence emission. Further, photocatalytic role of resulting molecular assembly was studied by means of the photoinduced degradation of methylene blue dye under UV light and direct sun irradiation at neutral pH. In order to enhance the long-term stability of the hybrid nanocatalyst, commercially available cellulose membrane was used as a support and magnetic recovery and reusability was achieved where the nanocatalyst retained more than 90 % of its efficiency even after four cycles. This simple strategy could initiate the development of new materials for wastewater treatment including membrane-based technologies. On the other hand, their sunlight-induced photocatalytic activity could easily be conducted to dye-synthesized solar cells or their enhanced photoluminescence can provide a strong basis for future bioimaging tools.Graphical Abstract.

Quantification of body iron and iron absorption in the REDS-II Donor Iron Status Evaluation (RISE) study.

Science.gov (United States)

Kiss, Joseph E; Birch, Rebecca J; Steele, Whitney R; Wright, David J; Cable, Ritchard G

2017-07-01

Repeated blood donation alters the iron balance of blood donors. We quantified these effects by analyzing changes in body iron as well as calculating iron absorbed per day for donors enrolled in a prospective study. For 1308 donors who completed a final study visit, we calculated total body iron at the enrollment and final visits and the change in total body iron over the course of the study. Taking into account iron lost from blood donations during the study and obligate losses, we also calculated the average amount of iron absorbed per day. First-time/reactivated donors at enrollment had iron stores comparable to previous general population estimates. Repeat donors had greater donation intensity and greater mean iron losses than first-time/reactivated donors, yet they had little change in total body iron over the study period, whereas first-time/reactivated donors had an average 35% drop. There was higher estimated iron absorption in the repeat donors (men: 4.49 mg/day [95% confidence interval [CI], 4.41-4.58 mg/day]; women: 3.75 mg/day [95% CI, 3.67-3.84 mg/day]) compared with estimated iron absorption in first-time/reactivated donors (men: 2.89 mg/day [95% CI, 2.75-3.04 mg/day]; women: 2.76 mg/day [95% CI, 2.64-2.87 mg/day]). The threshold for negative estimated iron stores (below "0" mg/kg stores) was correlated with the development of anemia at a plasma ferritin value of 10 ng/mL. These analyses provide quantitative data on changes in estimated total body iron for a broad spectrum of blood donors. In contrast to using ferritin alone, this model allows assessment of the iron content of red blood cells and the degree of both iron surplus and depletion over time. © 2017 AABB.

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... Research Home / < Back To Health Topics / Iron-Deficiency Anemia Iron-Deficiency Anemia Also known as Leer en español Iron-deficiency ... iron-deficiency anemia. Blood tests to screen for iron-deficiency anemia To screen for iron-deficiency anemia, your doctor ...

49 CFR 192.373 - Service lines: Cast iron and ductile iron.

Science.gov (United States)

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Service lines: Cast iron and ductile iron. 192.373... Regulators, and Service Lines § 192.373 Service lines: Cast iron and ductile iron. (a) Cast or ductile iron... cast iron pipe or ductile iron pipe is installed for use as a service line, the part of the service...

Comparison of Heavy-Duty Scuffing Behavior between Chromium-Based Ceramic Composite and Nickel-Chromium-Molybdenum-Coated Ring Sliding against Cast Iron Liner under Starvation

Directory of Open Access Journals (Sweden)

Yan Shen

2017-10-01

Full Text Available A running-in and starved lubrication experiment is designed to investigate the heavy-duty scuffing behavior of piston ring coatings against cast iron (Fe cylinder liner using the piston ring reciprocating liner test rig. The scuffing resistance of the piston ring with the chromium-based ceramic composite coating (CKS, and that with the thermally sprayed nickel-chromium-molybdenum coating (NCM is compared at different nominal pressures (40~100 MPa and temperatures (180~250 °C. With the failure time as a criterion, the rank order is as follows: NCM/Fe > CKS/Fe. Before the scoring occurs at the interface of the piston ring and cylinder liner (PRCL, the cast iron liner enters into a “polish wear” stage, and iron-based adhesive materials begin to form on the piston ring surface. With the macroscopic adhesion formation, the plastic shearing cycle causes surface damages mainly due to abrasive effects for the CKS/Fe pairs and adhesive effects for the NCM/Fe pairs.

Iron Oxide as an MRI Contrast Agent for Cell Tracking

Science.gov (United States)

Korchinski, Daniel J.; Taha, May; Yang, Runze; Nathoo, Nabeela; Dunn, Jeff F.

2015-01-01

Iron oxide contrast agents have been combined with magnetic resonance imaging for cell tracking. In this review, we discuss coating properties and provide an overview of ex vivo and in vivo labeling of different cell types, including stem cells, red blood cells, and monocytes/macrophages. Furthermore, we provide examples of applications of cell tracking with iron contrast agents in stroke, multiple sclerosis, cancer, arteriovenous malformations, and aortic and cerebral aneurysms. Attempts at quantifying iron oxide concentrations and other vascular properties are examined. We advise on designing studies using iron contrast agents including methods for validation. PMID:26483609

Comparative study of efficacy, tolerability and compliance of oral iron preparations (iron edetate, iron polymatose complex) and intramuscular iron sorbitol in iron deficiency anaemia in children

International Nuclear Information System (INIS)

Afzal, M.; Qureshi, S.M.; Lutafullah, M.

2009-01-01

To compare the efficacy, tolerability and compliance of oral iron preparations(iron edetate and Iron polymaltose complex) with each other and with intramuscular iron sorbitol in iron deficiency anaemia in children. A Randomized Controlled Trial (RCT) was carried out at the Paediatric Department of Combined Military Hospital (CMH) from January 2006 to December 2007. In total 146 children, up to 12 years age having haemoglobin (Hb%) less than 8 gm% were included. They were randomly distributed into three groups. Group A(64 cases) received oral sodium iron edetate (SIE), Group B (40 cases) received oral iron polymaltose complex (IPC) and group C (42 cases) received intramuscular iron sorbitol (IS) in recommended dosages. Rise in Hb%>10 gm% was kept as desired target. Maximum duration of treatment planned was 2 weeks for parenteral iron (group C) and 12 weeks for oral iron (groups A and B). Haematological parameters- Hb%, mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC) were measured at induction followed at 2 weeks, 4 weeks, 8 weeks and 12 weeks after start of treatment. Compliance and drop out rates were determined on each visit. Data was analyzed using SPSS version 10. ANOVA was used to analyze difference in rise in Hb% at various intervals. Statistically significant increase in mean Hb%, MCV, MCHC after 02 weeks was observed in group C (IS). Rise in these parameters became significant in group A (SIE) and B (IPC) after 04 weeks. Persistent rise was observed in oral groups at 08 and 12 weeks. Rise in Hb% was much faster in group C (IS). It took 2 weeks to achieve mean Hb% > 10 gm% and compliance rate was 40.5%, while to achieve same target, duration required was 8 weeks in group A (SIE) and 12 weeks in group B (IPC) and compliance rate was 39% and 30% respectively. Adverse effects were much more common with group A (SIE) as compared to other two groups. Intramuscular iron sorbitol is a reliable and

Nafion Coated Electrodes as Voltammetric Sensors for Iron Analysis in Sediments and Pore Waters: an Example from the Lagoon of Venice

Directory of Open Access Journals (Sweden)

Emanuele Argese

2001-09-01

Full Text Available Glassy carbon electrodes coated with Nafion are used for the ion-exchange voltammetric (IEV determination of Fe(II in the pore-waters and acidic extracts of sediments of the lagoon of Venice (Italy. The coated electrodes give reversible voltammetric signals, well resolved from background currents, which can be used for quantitative determinations. The yield of iron extracted by HCl from the sediment depends on the experimental conditions, in particular on the concentration of hydrochloric acid. By combining IEV on the acid extract with trapping and analysis of gaseous H2S evolved it is possible to obtain quantitative information both on the total content of iron dissolved by the acid attack and on the fraction of iron present in the form of acid volatile sulphides (AVS. As far as pore-waters are concerned, in this kind of samples the IEV determination of iron can be performed simply after dilution with HCl. The pore-waters here examined were sampled without alteration of their equilibrium conditions by using a suitable “in situ” sampler. IEV data obtained in samples from the lagoon of Venice (Italy show satisfactory correlation with previous results obtained using different analytical techniques.

Results of the First American Prospective Study of Intravenous Iron in Oral Iron-Intolerant Iron-Deficient Gravidas.

Science.gov (United States)

Auerbach, Michael; James, Stephanie E; Nicoletti, Melissa; Lenowitz, Steven; London, Nicola; Bahrain, Huzefa F; Derman, Richard; Smith, Samuel

2017-12-01

Anemia affects up to 42% of gravidas. Neonatal iron deficiency is associated with low birth weight, delayed growth and development, and increased cognitive and behavioral abnormalities. While oral iron is convenient, up to 70% report significant gastrointestinal toxicity. Intravenous iron formulations allowing replacement in one visit with favorable side-effect profiles decrease rates of anemia with improved hemoglobin responses and maternal fetal outcomes. Seventy-four oral iron-intolerant, second- and third-trimester iron-deficient gravidas were questioned for oral iron intolerance and treated with intravenous iron. All received 1000 mg of low-molecular-weight iron dextran in 250 mL normal saline. Fifteen minutes after a test dose, the remainder was infused over the balance of 1 hour. Subjects were called at 1, 2, and 7 days to assess delayed reactions. Four weeks postinfusion or postpartum, hemoglobin levels and iron parameters were measured. Paired t test was used for hemoglobin and iron; 58/73 women were questioned about interval growth and development of their babies. Seventy-three of 74 enrolled subjects completed treatment. Sixty had paired pre- and posttreatment data. The mean pre- and posthemoglobin concentrations were 9.7 and 10.8 g/dL (P iron deficiency anemia. Intravenous iron has less toxicity and is more effective, supporting moving it closer to frontline therapy. Copyright © 2017 Elsevier Inc. All rights reserved.

Studying Irony Detection Beyond Ironic Criticism: Let's Include Ironic Praise

Directory of Open Access Journals (Sweden)

Richard Bruntsch

2017-04-01

Full Text Available Studies of irony detection have commonly used ironic criticisms (i.e., mock positive evaluation of negative circumstances as stimulus materials. Another basic type of verbal irony, ironic praise (i.e., mock negative evaluation of positive circumstances is largely absent from studies on individuals' aptitude to detect verbal irony. However, it can be argued that ironic praise needs to be considered in order to investigate the detection of irony in the variety of its facets. To explore whether the detection ironic praise has a benefit beyond ironic criticism, three studies were conducted. In Study 1, an instrument (Test of Verbal Irony Detection Aptitude; TOVIDA was constructed and its factorial structure was tested using N = 311 subjects. The TOVIDA contains 26 scenario-based items and contains two scales for the detection of ironic criticism vs. ironic praise. To validate the measurement method, the two scales of the TOVIDA were experimentally evaluated with N = 154 subjects in Study 2. In Study 3, N = 183 subjects were tested to explore personality and ability correlates of the two TOVIDA scales. Results indicate that the co-variance between the ironic TOVIDA items was organized by two inter-correlated but distinct factors: one representing ironic praise detection aptitude and one representing ironic criticism detection aptitude. Experimental validation showed that the TOVIDA items truly contain irony and that item scores reflect irony detection. Trait bad mood and benevolent humor (as a facet of the sense of humor were found as joint correlates for both ironic criticism and ironic praise detection scores. In contrast, intelligence, trait cheerfulness, and corrective humor were found as unique correlates of ironic praise detection scores, even when statistically controlling for the aptitude to detect ironic criticism. Our results indicate that the aptitude to detect ironic praise can be seen as distinct from the aptitude to detect ironic

Iron and ferritin accumulate in separate cellular locations in Phaseolus seeds

DEFF Research Database (Denmark)

Cvitanich, Cristina; Przybylowicz, Wojciech J; Urbanski, Dorian Fabian

2010-01-01

and will assist in the production of staples with increased bioavailable iron. Results Here we reveal the distribution of iron in seeds of three Phaseolus species including thirteen genotypes of P. vulgaris, P. coccineus, and P. lunatus. We showed that high concentrations of iron accumulate in cells surrounding...... the provascular tissue of P. vulgaris and P. coccineus seeds. Using the Perls' Prussian blue method, we were able to detect iron in the cytoplasm of epidermal cells, cells near the epidermis, and cells surrounding the provascular tissue. In contrast, the protein ferritin that has been suggested as the major iron...... to P. vulgaris and P. coccineus, we did not observe iron accumulation in the cells surrounding the provascular tissues of P. lunatus cotyledons. A novel iron-rich genotype, NUA35, with a high concentration of iron both in the seed coat and cotyledons was bred from a cross between an Andean...

Biodistribution, pharmacokinetics, and toxicity of dendrimer-coated iron oxide nanoparticles in BALB/c mice

Directory of Open Access Journals (Sweden)

Salimi M

2018-03-01

Full Text Available Marzieh Salimi,1,2 Saeed Sarkar,1,2 Samaneh Fathi,3 Ali Mohammad Alizadeh,4 Reza Saber,2,3 Fatemeh Moradi,5 Hamid Delavari6 1Department of Medical Physics and Biomedical Engineering, Tehran University of Medical Sciences, Tehran, Iran; 2Research Center of Science and Technology in Medicine, Tehran University of Medical Sciences, Tehran, Iran; 3Department of Medical Nanotechnology, Tehran University of Medical Sciences, Tehran, Iran; 4Cancer Research Center, Tehran University of Medical Sciences, Tehran, Iran; 5Department of Medical Physiology, Tehran University of Medical Sciences, Tehran, Iran; 6Department of Materials Science and Engineering, Tarbiat Modares University, Tehran, Iran Background: The possibility of using a specific nanoparticle in nanomedicine highly depends on its biodistribution profile and biocompatibility. Due to growing demand for iron oxide nanoparticles (IONPs and dendrimers in biomedical applications, this study was performed to assess the biodistribution, pharmacokinetics, and toxicity of dendrimer-coated iron oxide nanoparticles (G4@IONPs. Materials and methods: IONPs were synthesized via co-precipitation and coated with the fourth generation (G4 of polyamidoamine (PAMAM dendrimer. To determine the biodistribution, 5 mg/mL G4@IONPs suspension was intraperitoneally injected into tumor-bearing BALB/c mice, and iron levels in blood and various organs, including the lung, liver, brain, heart, tumor, and kidney, were measured by inductively coupled plasma mass spectrometry (ICP-MS at 4, 8, 12, and 24 h after injection. Also, to investigate the toxicity of G4@IONPs, different concentrations of G4@IONPs were injected into BALB/c mice, and blood, renal, and hepatic factors were measured. Furthermore, histopathological staining was performed to investigate the effect of G4@IONPs on the liver and kidney tissues. Results: The results showed that the iron content was higher in the kidney, liver, and lung tissues 24 h after

Absorption of medicamental iron and iron from food

International Nuclear Information System (INIS)

Reizenstein, P.; Carlmark, B.; Ehn, L.; Forsberg, K.; Hoeglund, S.; Terpstra, T.

1976-01-01

Methods are reviewed for the measurement of iron absorption. The chemical balance method has been almost entirely supplanted by radioisotope methods, which include notably whole-body counting and measurement of incorporation of radioiron into red cells. A survey is also given of the various conditions that influence iron absorption, including chemical form of iron, amount of iron, accompanying diet. Absorption tests must be conducted under relevant conditions. (author)

Iron-Deficiency Anemia

Science.gov (United States)

... To Health Topics / Iron-Deficiency Anemia Iron-Deficiency Anemia Also known as Leer en español Iron-deficiency ... anemia. Blood tests to screen for iron-deficiency anemia To screen for iron-deficiency anemia, your doctor ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... risk for iron-deficiency anemia, including: Vegetarian or vegan eating patterns. Not eating enough iron-rich foods, ... iron-fortified foods that have iron added. Vegetarian diets can provide enough iron if you choose nonmeat ...

Effect of cracks in coating on gas release from a fuel microparticle

International Nuclear Information System (INIS)

Bondarenko, A.G.; Gudkov, A.N.; Tselishchev, Yu.V.

1988-01-01

Effect of cracks in protective coating on gas release from a fuel microparticle is investigated in a general form. A fuel microparticle comprizing a kern, a buffer layer and an external protective coating is considered. The pressure of radioactive inert gases in the microparticle buffer layer is evaluated within the 1000-1800 K temperature range on the base of diffusion-defect-trap transport theory. It is shown that the process of radionuclide adsorption interaction with the coating material leads to a more abrupt than by exponent, weakening of mass transfer coefficient. In this case for long-living isotopes the effect of adsorption processes manifests weaker than for short-living ones. Mass transfer coefficient for the crack system depends sufficiently on the total pressure of gas mixture under the coating while for a single cracks such dependence is not observed. A conclusion is drawn that the obtained ratios can be applied for evaluating the character of fuel microparticle protective coating destruction (single non-intersecting cracks or a crack system) using the data on various nuclide release. These ratios can be also applied for the choice of the coating thichness under which gaseous fission product release from the fuel microparticle in case of its protective coating failure does not exceed the acceptable limits

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... Iron-Deficiency Anemia Iron-Deficiency Anemia Also known as Leer en español Iron-deficiency anemia is a ... address the cause of your iron deficiency, such as any underlying bleeding. If undiagnosed or untreated, iron- ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... To Health Topics / Iron-Deficiency Anemia Iron-Deficiency Anemia Also known as Leer en español Iron-deficiency ... anemia. Blood tests to screen for iron-deficiency anemia To screen for iron-deficiency anemia, your doctor ...

Surface anisotropy of iron oxide nanoparticles and slabs from first principles: Influence of coatings and ligands as a test of the Heisenberg model

Energy Technology Data Exchange (ETDEWEB)

Brymora, Katarzyna; Calvayrac, Florent, E-mail: Florent.Calvayrac@univ-lemans.fr

2017-07-15

Highlights: • A new method is given to extract surface anisotropies from ab initio calculations. • Heisenberg model for magnetic clusters and surfaces is validated in simple cases. • Ligands, metallic clusters, or coatings degrade the validity of the Heisenberg model. • Values for surface anisotropies, volume anisotropies, exchange constants are computed. • Results are in agreement with experimental data, previous theoretical findings. - Abstract: We performed ab initio computations of the magnetic properties of simple iron oxide clusters and slabs. We considered an iron oxide cluster functionalized by a molecule or glued to a gold cluster of the same size. We also considered a magnetite slab coated by cobalt oxide or a mixture of iron oxide and cobalt oxide. The changes in magnetic behavior were explored using constrained magnetic calculations. A possible value for the surface anisotropy was estimated from the fit of a classical Heisenberg model on ab initio results. The value was found to be compatible with estimations obtained by other means, or inferred from experimental results. The addition of a ligand, coating, or of a metallic nanoparticle to the systems degraded the quality of the description by the Heisenberg Hamiltonian. Proposing a change in the anisotropies allowing for the proportion of each transition atom we could get a much better description of the magnetism of series of hybrid cobalt and iron oxide systems.

Serum iron and total iron binding capacity levels among the abo ...

African Journals Online (AJOL)

Iron deficiency anaemia is a common tropical disease. Iron plays a very important role in the human body. The understanding of the different blood groups ability to retain iron in their system can give an insight into their ability to handle the disease Iron deficiency anaemia. Serum Iron, Total Iron Binding Capacity (TIBC) and ...

Zinc deficiency-induced iron accumulation, a consequence of alterations in iron regulatory protein-binding activity, iron transporters, and iron storage proteins.

Science.gov (United States)

Niles, Brad J; Clegg, Michael S; Hanna, Lynn A; Chou, Susan S; Momma, Tony Y; Hong, Heeok; Keen, Carl L

2008-02-22

One consequence of zinc deficiency is an elevation in cell and tissue iron concentrations. To examine the mechanism(s) underlying this phenomenon, Swiss 3T3 cells were cultured in zinc-deficient (D, 0.5 microM zinc), zinc-supplemented (S, 50 microM zinc), or control (C, 4 microM zinc) media. After 24 h of culture, cells in the D group were characterized by a 50% decrease in intracellular zinc and a 35% increase in intracellular iron relative to cells in the S and C groups. The increase in cellular iron was associated with increased transferrin receptor 1 protein and mRNA levels and increased ferritin light chain expression. The divalent metal transporter 1(+)iron-responsive element isoform mRNA was decreased during zinc deficiency-induced iron accumulation. Examination of zinc-deficient cells revealed increased binding of iron regulatory protein 2 (IRP2) and decreased binding of IRP1 to a consensus iron-responsive element. The increased IRP2-binding activity in zinc-deficient cells coincided with an increased level of IRP2 protein. The accumulation of IRP2 protein was independent of zinc deficiency-induced intracellular nitric oxide production but was attenuated by the addition of the antioxidant N-acetylcysteine or ascorbate to the D medium. These data support the concept that zinc deficiency can result in alterations in iron transporter, storage, and regulatory proteins, which facilitate iron accumulation.

Mammalian iron metabolism and its control by iron regulatory proteins☆

Science.gov (United States)

Anderson, Cole P.; Shen, Lacy; Eisenstein, Richard S.; Leibold, Elizabeth A.

2013-01-01

Cellular iron homeostasis is maintained by iron regulatory proteins 1 and 2 (IRP1 and IRP2). IRPs bind to iron-responsive elements (IREs) located in the untranslated regions of mRNAs encoding protein involved in iron uptake, storage, utilization and export. Over the past decade, significant progress has been made in understanding how IRPs are regulated by iron-dependent and iron-independent mechanisms and the pathological consequences of IRP2 deficiency in mice. The identification of novel IREs involved in diverse cellular pathways has revealed that the IRP–IRE network extends to processes other than iron homeostasis. A mechanistic understanding of IRP regulation will likely yield important insights into the basis of disorders of iron metabolism. This article is part of a Special Issue entitled: Cell Biology of Metals. PMID:22610083

Iron oxide shell coating on nano silicon prepared from the sand for lithium-ion battery application

Science.gov (United States)

Furquan, Mohammad; Vijayalakshmi, S.; Mitra, Sagar

2018-05-01

Elemental silicon, due to its high specific capacity (4200 mAh g-1) and non-toxicity is expected to be an attractive anode material for Li-ion battery. But its huge expansion volume (> 300 %) during charging of battery, leads to pulverization and cracking in the silicon particles and causes sudden failure of the Li-ion battery. In this work, we have designed yolk-shell type morphology of silicon, prepared from carbon coated silicon nanoparticles soaked in aqueous solution of ferric nitrate and potassium hydroxide. The soaked silicon particles were dried and finally calcined at 800 °C for 30 minutes. The product obtained is deprived of carbon and has a kind of yolk-shell morphology of nano silicon with iron oxide coating (Si@Iron oxide). This material has been tested for half-cell lithium-ion battery configuration. The discharge capacity is found to be ≈ 600 mAh g-1 at a current rate of 1.0 A g-1 for 200 cycles. It has shown a stable performance as anode for Li-ion battery application.

Iron-binding haemerythrin RING ubiquitin ligases regulate plant iron responses and accumulation

Science.gov (United States)

Kobayashi, Takanori; Nagasaka, Seiji; Senoura, Takeshi; Itai, Reiko Nakanishi; Nakanishi, Hiromi; Nishizawa, Naoko K.

2013-01-01

Iron is essential for most living organisms. Plants transcriptionally induce genes involved in iron acquisition under conditions of low iron availability, but the nature of the deficiency signal and its sensors are unknown. Here we report the identification of new iron regulators in rice, designated Oryza sativa Haemerythrin motif-containing Really Interesting New Gene (RING)- and Zinc-finger protein 1 (OsHRZ1) and OsHRZ2. OsHRZ1, OsHRZ2 and their Arabidopsis homologue BRUTUS bind iron and zinc, and possess ubiquitination activity. OsHRZ1 and OsHRZ2 are susceptible to degradation in roots irrespective of iron conditions. OsHRZ-knockdown plants exhibit substantial tolerance to iron deficiency, and accumulate more iron in their shoots and grains irrespective of soil iron conditions. The expression of iron deficiency-inducible genes involved in iron utilization is enhanced in OsHRZ-knockdown plants, mostly under iron-sufficient conditions. These results suggest that OsHRZ1 and OsHRZ2 are iron-binding sensors that negatively regulate iron acquisition under conditions of iron sufficiency. PMID:24253678

Extracting phosphoric iron under laboratorial conditions smelting bog iron ores

International Nuclear Information System (INIS)

Török, B; Thiele, A

2013-01-01

In recent years it has been indicated by archaeometric investigations that phosphoric-iron (P-iron, low carbon steel with 0,5-1,5wt% P), which is an unknown and unused kind of steel in the modern industry, was widely used in different parts of the world in medieval times. In this study we try to explore the role of phosphorus in the arhaeometallurgy of iron and answer some questions regarding the smelting bog iron ores with high P-content. XRF analyses were performed on bog iron ores collected in Somogy county. Smelting experiments were carried out on bog iron ores using a laboratory model built on the basis of previously conducted reconstructed smelting experiments in copies of excavated furnaces. The effect of technological parameters on P-content of the resulted iron bloom was studied. OM and SEM-EDS analyses were carried out on the extracted iron and slag samples. On the basis of the material analyses it can be stated that P-iron is usually extracted but the P-content is highly affected by technological parameters. Typical microstructures of P-iron and of slag could also be identified. It could also be established that arsenic usually solved in high content in iron as well

Iron Therapy in Patients with Heart Failure and Iron Deficiency: Review of Iron Preparations for Practitioners.

Science.gov (United States)

Drozd, Marcin; Jankowska, Ewa A; Banasiak, Waldemar; Ponikowski, Piotr

2017-06-01

In patients with heart failure (HF), iron deficiency (ID) correlates with decreased exercise capacity and poor health-related quality of life, and predicts worse outcomes. Both absolute (depleted iron stores) and functional (where iron is unavailable for dedicated tissues) ID can be easily evaluated in patients with HF using standard laboratory tests (assessment of serum ferritin and transferrin saturation). Intravenous iron therapy in iron-deficient patients with HF and reduced ejection fraction has been shown to alleviate HF symptoms and improve exercise capacity and quality of life. In this paper, we provide information on how to diagnose ID in HF. Further we discuss pros and cons of different iron preparations and discuss the results of major trials implementing iron supplementation in HF patients, in order to provide practical guidance for clinicians on how to manage ID in patients with HF.

Siderophore-mediated iron trafficking in humans is regulated by iron

Science.gov (United States)

Liu, Zhuoming; Lanford, Robert; Mueller, Sebastian; Gerhard, Glenn S.; Luscieti, Sara; Sanchez, Mayka; Devireddy, L.

2013-01-01

Siderophores are best known as small iron binding molecules that facilitate microbial iron transport. In our previous study we identified a siderophore-like molecule in mammalian cells and found that its biogenesis is evolutionarily conserved. A member of the short chain dehydrogenase family of reductases, 3-OH butyrate dehydrogenase (BDH2) catalyzes a rate-limiting step in the biogenesis of the mammalian siderophore. We have shown that depletion of the mammalian siderophore by inhibiting expression of bdh2 results in abnormal accumulation of cellular iron and mitochondrial iron deficiency. These observations suggest that the mammalian siderophore is a critical regulator of cellular iron homeostasis and facilitates mitochondrial iron import. By utilizing bioinformatics, we identified an iron-responsive element (IRE; a stem-loop structure that regulates genes expression post-transcriptionally upon binding to iron regulatory proteins or IRPs) in the 3′-untranslated region (3′-UTR) of the human BDH2 (hBDH2) gene. In cultured cells as well as in patient samples we now demonstrate that the IRE confers iron-dependent regulation on hBDH2 and binds IRPs in RNA electrophoretic mobility shift assays. In addition, we show that the hBDH2 IRE associates with IRPs in cells and that abrogation of IRPs by RNAi eliminates the iron-dependent regulation of hBDH2 mRNA. The key physiologic implication is that iron-mediated post-transcriptional regulation of hBDH2 controls mitochondrial iron homeostasis in human cells. These observations provide a new and an unanticipated mechanism by which iron regulates its intracellular trafficking. PMID:22527885

New insights into iron deficiency and iron deficiency anemia.

Science.gov (United States)

Camaschella, Clara

2017-07-01

Recent advances in iron metabolism have stimulated new interest in iron deficiency (ID) and its anemia (IDA), common conditions worldwide. Absolute ID/IDA, i.e. the decrease of total body iron, is easily diagnosed based on decreased levels of serum ferritin and transferrin saturation. Relative lack of iron in specific organs/tissues, and IDA in the context of inflammatory disorders, are diagnosed based on arbitrary cut offs of ferritin and transferrin saturation and/or marker combination (as the soluble transferrin receptor/ferritin index) in an appropriate clinical context. Most ID patients are candidate to traditional treatment with oral iron salts, while high hepcidin levels block their absorption in inflammatory disorders. New iron preparations and new treatment modalities are available: high-dose intravenous iron compounds are becoming popular and indications to their use are increasing, although long-term side effects remain to be evaluated. Copyright © 2017 Elsevier Ltd. All rights reserved.

Iron absorption studies

International Nuclear Information System (INIS)

Ekenved, G.

1976-01-01

The main objective of the present work was to study iron absorption from different iron preparations in different types of subjects and under varying therapeutic conditions. The studies were performed with different radioiron isotope techniques and with a serum iron technique. The preparations used were solutions of ferrous sulphate and rapidly-disintegrating tablets containing ferrous sulphate, ferrous fumarate and ferrous carbonate and a slow-release ferrous sulphate tablet of an insoluble matrix type (Duroferon Durules). The serum iron method was evaluated and good correlation was found between the serum iron response and the total amount of iron absorbed after an oral dose of iron given in solution or in tablet form. New technique for studying the in-vivo release properties of tablets was presented. Iron tablets labelled with a radio-isotope were given to healthy subjects. The decline of the radioactivity in the tablets was followed by a profile scanning technique applied to different types of iron tablets. The release of iron from the two types of tablets was shown to be slower in vivo than in vitro. It was found that co-administration of antacids and iron tablets led to a marked reduction in the iron absorption and that these drugs should not be administered sumultaneously. A standardized meal markedly decreased the absorbability of iron from iron tablets. The influence of the meal was more marked with rapidly-disintegrating than with slow-release ferrous sulphate tablets. The absorption from rapidly-disintegrating and slow-release ferrous sulphate tablets was compared under practical clinical conditions during an extended treatment period. The studies were performed in healthy subjects, blood donors and patients with iron deficiency anaemia and it was found that the absorption of iron from the slow-release tablets was significantly better than from the rapidly-disintegrating tablets in all three groups of subjects. (author)

Magnetophoretic manipulation in microsystem using carbonyl iron-polydimethylsiloxane microstructures

OpenAIRE

Faivre, Magalie; Gelszinnis, Renaud; Degouttes, Jérôme; Terrier, Nicolas; Rivière, Charlotte; Ferrigno, Rosaria; Deman, Anne-Laure

2014-01-01

This paper reports the use of a recent composite material, noted hereafter i-PDMS, made of carbonyl iron microparticles mixed in a PolyDiMethylSiloxane (PDMS) matrix, for magnetophoretic functions such as capture and separation of magnetic species. We demonstrated that this composite which combine the advantages of both components, can locally generate high gradients of magnetic field when placed between two permanent magnets. After evaluating the magnetic susceptibility of the material as a ...

Nitrate-dependent iron oxidation limits iron transport in anoxic ocean regions

Science.gov (United States)

Scholz, Florian; Löscher, Carolin R.; Fiskal, Annika; Sommer, Stefan; Hensen, Christian; Lomnitz, Ulrike; Wuttig, Kathrin; Göttlicher, Jörg; Kossel, Elke; Steininger, Ralph; Canfield, Donald E.

2016-11-01

Iron is an essential element for life on Earth and limits primary production in large parts of the ocean. Oxygen-free continental margin sediments represent an important source of bioavailable iron to the ocean, yet little of the iron released from the seabed reaches the productive sea surface. Even in the anoxic water of oxygen minimum zones, where iron solubility should be enhanced, most of the iron is rapidly re-precipitated. To constrain the mechanism(s) of iron removal in anoxic ocean regions we explored the sediment and water in the oxygen minimum zone off Peru. During our sampling campaign the water column featured two distinct redox boundaries separating oxic from nitrate-reducing (i.e., nitrogenous) water and nitrogenous from weakly sulfidic water. The sulfidic water mass in contact with the shelf sediment contained elevated iron concentrations >300 nM. At the boundary between sulfidic and nitrogenous conditions, iron concentrations dropped sharply to <20 nM coincident with a maximum in particulate iron concentration. Within the iron gradient, we found an increased expression of the key functional marker gene for nitrate reduction (narG). Part of this upregulation was related to the activity of known iron-oxidizing bacteria. Collectively, our data suggest that iron oxidation and removal is induced by nitrate-reducing microbes, either enzymatically through anaerobic iron oxidation or by providing nitrite for an abiotic reaction. Given the important role that iron plays in nitrogen fixation, photosynthesis and respiration, nitrate-dependent iron oxidation likely represents a key-link between the marine biogeochemical cycles of nitrogen, oxygen and carbon.

In-situ surface hardening of cast iron by surface layer metallurgy

International Nuclear Information System (INIS)

Fischer, Sebastian F.; Muschna, Stefan; Bührig-Polaczek, Andreas; Bünck, Matthias

2014-01-01

Abrasive wear is a serious problem in many cast iron castings used in industry. To minimize failure and repair of these components, different strategies exist to improve their surface microhardness thus enhancing their wear resistance. However, most of these methods lead to very brittle and/or expensive castings. In the current work a new method for surface hardening is presented which utilizes surface layer metallurgy to generate in-situ a boron-enriched white cast iron surface layer with a high microhardness on a gray cast iron casting. To do this, sand molds are coated with a ferroboron suspension and cast with a cast iron melt. After solidification, a 100–900 µm thick layer of boron-enriched ledeburite is formed on the surface of the casting which produces an increase in the average microhardness from 284 HV 0.1 ±52 HV 0.1 to 505 HV 0.1 ±87 HV 0.1 . Analyses of the samples' core reveal a typical cast iron microstructure which leads to the conclusion that the coating mainly affects the castings' surface. By varying the grain size of the ferroboron powder in the coatings, it is shown that a powder size ≤100 µm is most suitable to create a boron-enriched ledeburite surface layer possessing high hardness values

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... and severity. Treatments may include iron supplements, procedures, surgery, and dietary ... iron supplements, also called iron pills or oral iron, by mouth once or several times a ...

Efficacy of iron fortification compared to iron supplementation among Vietnamese schoolchildren.

Science.gov (United States)

Thi Le, Huong; Brouwer, Inge D; Burema, Jan; Nguyen, Khan Cong; Kok, Frans J

2006-12-05

The effect of iron fortification is generally assumed to be less than iron supplementation; however, the magnitude of difference in effects is not known. The present study aims to compare the efficacy of these two strategies on anaemia and iron status. After screening on low Hb, 425 anaemic children in six primary schools in Tam Nong district of Phu Tho province were included in a randomized, placebo-controlled trial comparing two groups receiving iron fortified instant noodles or iron supplementation for 6 months and a control group, with children in all groups having been dewormed. Blood samples were collected before and after intervention for haemoglobin, serum ferritin (SF), serum transferrin receptor (TfR), C-reactive protein (CRP), and haemoglobinopathies analysis. Regression analysis was used to assess the effect of iron fortification and iron supplementation on haemoglobin concentration, SF, TfR, body iron, and anaemic status as outcome variables. The improvement of haemoglobin, SF, and body iron level in the group receiving iron fortification was 42% (2.6 g/L versus 6.2 g/L), 20% (23.5 microg/L versus 117.3 microg/L), and 31.3% (1.4 mg/kg versus 4.4 mg/kg) of that in the iron supplementation group. The prevalence of anaemia dropped to 15.1% in the control group, with an additional reduction of anaemia of 8.5% in the iron supplementation group. The additional reduction due to iron fortification was 5.4%, which amounts to well over 50% of the impact of supplementation. In conclusion, the efficacy of iron fortification based on reduction of prevalence of anaemia, and on the change in haemoglobin level, is about half of the maximum impact of supplementation in case of optimal compliance. Thus, in a population of anaemic children with mild iron deficiency, iron fortification should be the preferred strategy to combat anaemia.

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... iron-rich foods, especially during certain stages of life when more iron is needed, such as childhood and pregnancy. Good sources of iron are meat, poultry, fish, and iron- ...

Measurement of iron absorption from meals contaminated with iron

International Nuclear Information System (INIS)

Hallberg, L.; Bjoern-Rasmussen, E.

1981-01-01

A method is described to measure in vitro the extent of isotopic exchange between the native nonheme food iron and added inorganic reduction to radioiron tracer. The food is digested with pepsin and trypsin in the presence of radioiron. The exchangeability of food iron is calculated from the specific activity in the food and in an extract of bathophenantroline in isoamyl alcohol obtained after digesting this food. The precision and accuracy of the method is illustrated by two kinds of studies, those in which different amounts of contamination iron are added to a meal and those evaluating contamination iron in natural meals. The present method will make it possible to measure validly iron absorption from meals contaminated with unknown amounts of iron of unknown exchangeability with the extrinsic radioiron tracer

Iron in diet

Science.gov (United States)

... Reasonable amounts of iron are also found in lamb, pork, and shellfish. Iron from vegetables, fruits, grains, ... strawberries, tomatoes, and potatoes) also increase iron absorption. Cooking foods in a cast-iron skillet can also ...

49 CFR 192.489 - Remedial measures: Cast iron and ductile iron pipelines.

Science.gov (United States)

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Remedial measures: Cast iron and ductile iron... for Corrosion Control § 192.489 Remedial measures: Cast iron and ductile iron pipelines. (a) General graphitization. Each segment of cast iron or ductile iron pipe on which general graphitization is found to a...

Iron status in Danish women, 1984-1994: a cohort comparison of changes in iron stores and the prevalence of iron deficiency and iron overload

DEFF Research Database (Denmark)

Milman, N.; Byg, K.E.; Ovesen, Lars

2003-01-01

Background and objectives: From 1954 to 1986, flour in Denmark was fortified with 30 mg carbonyl iron per kilogram. This mandatory enrichment of cereal products was abolished in 1987. The aim was to evaluate iron status in the Danish female population before and after abolishment of iron...... fortification. Methods: Iron status, serum ferritin and haemoglobin, was assessed in population surveys in 1983-1984 comprising 1221 Caucasian women (1089 non-blood-donors, 130 donors) and in 1993-1994 comprising 1261 women (1155 non-blood-donors, 104 donors) equally distributed in age cohorts of 40, 50, 60......, postmenopausal women had median ferritin of 75 mug/L and in 1994 of 93 mug/L (P iron stores (ferritin iron stores (ferritin less...

Fabrication and Properties of Iron-based Soft Magnetic Composites Coated with NiZnFe2O4

Directory of Open Access Journals (Sweden)

WU Shen

2017-07-01

Full Text Available This paper focuses on iron-based soft magnetic composites which were synthesized by utilizing the sol-gel method prepared Ni-Zn ferrite particles as insulating compound to coat iron powder, and the influence of NiZnFe2O4 content and molding pressure on the magnetic properties was studied. The morphology, magnetic properties and density of Ni-Zn ferrite insulated compacts were investigated. Scanning electron microscope,line-scan EDX analysis and distribution maps show that the iron particle surface is covered with a thin layer of uniform Ni-Zn ferrites. The existing of the insulating layer can effectively improve the electrical resistivity of soft magnetic composites. Magnetic measurements show that the real part of permeability decreases with the increase of the Ni-Zn ferrite content, and the sample with 3%(mass fraction, the same below Ni-Zn ferrite has an acceptable real part and minimum imaginary part of permeability in comparison with other samples. Results show that the addition of NiZnFe2O4 can dramatically decrease the internal magnetic loss, the magnetic loss of coated samples decreases by 83.8% as compared with that of uncoated samples at 100kHz. The density of the Fe-3%NiZnFe2O4 compacts reaches 7.14g/cm3 and the saturation magnetization is 1.47T when the molding pressure is 1000MPa.

Comparison of Carbon XANES Spectra from an Iron Sulfide from Comet Wild 2 with an Iron Sulfide Interplanetary Dust Particle

Science.gov (United States)

Wirick, S.; Flynn, G. J.; Keller, L. P.; Sanford, S. A.; Zolensky, M. E.; Messenger, Nakamura K.; Jacobsen, C.

2008-01-01

Among one of the first particles removed from the aerogel collector from the Stardust sample return mission was an approx. 5 micron sized iron sulfide. The majority of the spectra from 5 different sections of this particle suggests the presence of aliphatic compounds. Due to the heat of capture in the aerogel we initially assumed these aliphatic compounds were not cometary but after comparing these results to a heated iron sulfide interplanetary dust particle (IDP) we believe our initial interpretation of these spectra was not correct. It has been suggested that ice coating on iron sulfides leads to aqueous alteration in IDP clusters which can then lead to the formation of complex organic compounds from unprocessed organics in the IDPs similar to unprocessed organics found in comets [1]. Iron sulfides have been demonstrated to not only transform halogenated aliphatic hydrocarbons but also enhance the bonding of rubber to steel [2,3]. Bromfield and Coville (1997) demonstrated using Xray photoelectron spectroscopy that "the surface enhancement of segregated sulfur to the surface of sulfided precipitated iron catalysts facilitates the formation of a low-dimensional structure of extraordinary properties" [4]. It may be that the iron sulfide acts in some way to protect aliphatic compounds from alteration due to heat.

Iron Dextran Injection

Science.gov (United States)

Iron dextran injection is used to treat iron-deficiency anemia (a lower than normal number of red blood cells ... treated with iron supplements taken by mouth. Iron dextran injection is in a class of medications called ...

Structure and magnetic properties of iron-based soft magnetic composite with Ni-Cu-Zn ferrite-silicone insulation coating

Science.gov (United States)

Li, Wangchang; Wang, Wei; Lv, Junjun; Ying, Yao; Yu, Jing; Zheng, Jingwu; Qiao, Liang; Che, Shenglei

2018-06-01

This paper investigates the structure and magnetic properties of Ni-Cu-Zn ferrite-silicone coated iron-based soft magnetic composites (SMCs). Scanning electron microscopy coupled with a energy-dispersive spectroscopy (EDS) analysis revealed that the Ni-Cu-Zn ferrite and silicone resin were uniformly coated on the surface of iron powders. By controlling the composition of the coating layer, low total core loss of 97.7 mW/cm3 (eddy current loss of 48 mW/cm3, hysteresis loss of 49.7 mW/cm3, measured at 100 kHz and 0.02 T) and relatively high effective permeability of 72.5 (measured at 100 kHz) were achieved. In addition, the as-prepared SMCs displayed higher electrical resistivity, good magnetic characteristics over a wide range of frequencies (20-200 kHz) and ideal the D-C bias properties (more than 75% at H = 50 Oe). Furthermore, higher elastic modulus and hardness of SMCs, which means that the coating layer has good mechanical properties and is not easily damaged during the pressing process, were obtained in this paper. The results of this work indicate that the Ni-Cu-Zn ferrite-silicone coated SMCs have desirable properties which would make them suitable for application in the fields of the electric-magnetic switching devices, such as inductance coils, transformer cores, synchronous electric motors and resonant inductors.

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... to moderate iron-deficiency anemia, or red blood cell transfusion for severe iron-deficiency anemia. You may ... body needs iron to make healthy red blood cells. Iron-deficiency anemia usually develops over time because ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... you are diagnosed with iron-deficiency anemia. Risk Factors You may have an increased risk for iron- ... iron-deficiency anemia if you have certain risk factors , including pregnancy. To prevent iron-deficiency anemia, your ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... from developing iron-deficiency anemia. Foods that are good sources of iron include dried beans, dried fruits, ... iron is needed, such as childhood and pregnancy. Good sources of iron are meat, poultry, fish, and ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... enough iron-rich foods, such as meat and fish, may result in you getting less than the ... pregnancy. Good sources of iron are meat, poultry, fish, and iron-fortified foods that have iron added. ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... that are good sources of iron include dried beans, dried fruits, eggs, lean red meat, salmon, iron- ... of iron, including iron-fortified breads and cereals, beans, tofu, dried fruits, and spinach and other dark ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... developing iron-deficiency anemia. Foods that are good sources of iron include dried beans, dried fruits, eggs, ... is needed, such as childhood and pregnancy. Good sources of iron are meat, poultry, fish, and iron- ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... iron in your body is low. For this reason, other iron tests are also done. Ferritin measure ... iron is needed, such as childhood and pregnancy. Good sources of iron are meat, poultry, fish, and ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... develop new therapies for conditions that affect the balance of iron in the body and lead to ... Disease Control and Prevention) Iron - Health Professional Fact Sheet (NIH) Iron Dietary Supplement Fact Sheet (NIH) Iron- ...

Mineralogy and geochemistry of banded iron formation and iron ...

Indian Academy of Sciences (India)

The geological complexities of banded iron formation (BIF) and associated iron ores of Jilling–. Langalata iron ore ...... sure to sea water. Uranium in these samples varies ..... Ce oxidation and removal (Elderfield and Greaves. 1982; De Baar et ...

Efficacy of iron fortification compared to iron supplementation among Vietnamese schoolchildren

Directory of Open Access Journals (Sweden)

Nguyen Khan

2006-12-01

Full Text Available Abstract The effect of iron fortification is generally assumed to be less than iron supplementation; however, the magnitude of difference in effects is not known. The present study aims to compare the efficacy of these two strategies on anaemia and iron status. After screening on low Hb, 425 anaemic children in six primary schools in Tam Nong district of Phu Tho province were included in a randomized, placebo-controlled trial comparing two groups receiving iron fortified instant noodles or iron supplementation for 6 months and a control group, with children in all groups having been dewormed. Blood samples were collected before and after intervention for haemoglobin, serum ferritin (SF, serum transferrin receptor (TfR, C-reactive protein (CRP, and haemoglobinopathies analysis. Regression analysis was used to assess the effect of iron fortification and iron supplementation on haemoglobin concentration, SF, TfR, body iron, and anaemic status as outcome variables. The improvement of haemoglobin, SF, and body iron level in the group receiving iron fortification was 42% (2.6 g/L versus 6.2 g/L, 20% (23.5 μg/L versus 117.3 μg/L, and 31.3% (1.4 mg/kg versus 4.4 mg/kg of that in the iron supplementation group. The prevalence of anaemia dropped to 15.1% in the control group, with an additional reduction of anaemia of 8.5% in the iron supplementation group. The additional reduction due to iron fortification was 5.4%, which amounts to well over 50% of the impact of supplementation. In conclusion, the efficacy of iron fortification based on reduction of prevalence of anaemia, and on the change in haemoglobin level, is about half of the maximum impact of supplementation in case of optimal compliance. Thus, in a population of anaemic children with mild iron deficiency, iron fortification should be the preferred strategy to combat anaemia.

Radiation dose rate affects the radiosensitization of MCF-7 and HeLa cell lines to X-rays induced by dextran-coated iron oxide nanoparticles.

Science.gov (United States)

Khoshgard, Karim; Kiani, Parvaneh; Haghparast, Abbas; Hosseinzadeh, Leila; Eivazi, Mohammad Taghi

2017-08-01

The aim of radiotherapy is to deliver lethal damage to cancerous tissue while preserving adjacent normal tissues. Radiation absorbed dose of the tumoral cells can increase when high atomic nanoparticles are present in them during irradiation. Also, the dose rate is an important aspect in radiation effects that determines the biological results of a given dose. This in vitro study investigated the dose-rate effect on the induced radiosensitivity by dextran-coated iron oxide in cancer cells. HeLa and MCF-7 cells were cultured in vitro and incubated with different concentrations of dextran-coated iron oxide nanoparticles. They were then irradiated with 6 MV photons at dose rates of 43, 185 and 370 cGy/min. The MTT test was used to obtain the cells' survival after 48 h of irradiations. Incubating the cells with the nanoparticles at concentrations of 10, 40 and 80 μg/ml showed no significant cytotoxicity effect. Dextran-coated iron oxide nanoparticles showed more radiosensitivity effect by increasing the dose rate and nanoparticles concentration. Radiosensitization enhancement factors of MCF-7 and HeLa cells at a dose-rate of 370 cGy/min and nanoparticles' concentration of 80 μg/ml were 1.21 ± 0.06 and 1.19 ± 0.04, respectively. Increasing the dose rate of 6 MV photons irradiation in MCF-7 and HeLa cells increases the radiosensitization induced by the dextran-coated iron nanoparticles in these cells.

Method for preparing high cure temperature rare earth iron compound magnetic material

Science.gov (United States)

Huang, Yuhong; Wei, Qiang; Zheng, Haixing

2002-01-01

Insertion of light elements such as H,C, or N in the R.sub.2 Fe.sub.17 (R=rare earth metal) series has been found to modify the magnetic properties of these compounds, which thus become prospective candidates for high performance permanent magnets. The most spectacular changes are increases of the Curie temperature, T.sub.c, of the magnetization, M.sub.s, and of coercivity, H.sub.c, upon interstitial insertion. A preliminary product having a component R--Fe--C,N phase is produced by a chemical route. Rare earth metal and iron amides are synthesized followed by pyrolysis and sintering in an inert or reduced atmosphere, as a result of which, the R--Fe--C,N phases are formed. Fabrication of sintered rare earth iron nitride and carbonitride bulk magnet is impossible via conventional process due to the limitation of nitridation method.

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... for your body to absorb iron from the gastrointestinal tract (GI tract). Blood loss When you lose blood, ... iron deficiency. Endurance athletes lose iron through their gastrointestinal tracts. They also lose iron through the breakdown of ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... Home / < Back To Health Topics / Iron-Deficiency Anemia Iron-Deficiency Anemia Also known as Leer en español ... bleeding Consuming less than recommended daily amounts of iron Iron-deficiency anemia can be caused by getting ...

Iron homeostasis and its disruption in mouse lung in iron deficiency and overload.

Science.gov (United States)

Giorgi, Gisela; D'Anna, María Cecilia; Roque, Marta Elena

2015-10-01

What is the central question of this study? The aim was to explore the role and hitherto unclear mechanisms of action of iron proteins in protecting the lung against the harmful effects of iron accumulation and the ability of pulmonary cells to mobilize iron in iron deficiency. What is the main finding and its importance? We show that pulmonary hepcidin appears not to modify cellular iron mobilization in the lung. We propose pathways for supplying iron to the lung in iron deficiency and for protecting the lung against iron excess in iron overload, mediated by the co-ordinated action of iron proteins, such as divalent metal transporter 1, ZRT-IRE-like-protein 14, transferrin receptor, ferritin, haemochromatosis-associated protein and ferroportin. Iron dyshomeostasis is associated with several forms of chronic lung disease, but its mechanisms of action remain to be elucidated. The aim of the present study was to determine the role of the lung in whole-animal models with iron deficiency and iron overload, studying the divalent metal transporter 1 (DMT1), ZRT-IRE-like protein 14 (ZIP14), transferrin receptor (TfR), haemochromatosis-associated protein (HFE), hepcidin, ferritin and ferroportin (FPN) expression. In each model, adult CF1 mice were divided into the following groups (six mice per group): (i) iron-overload model, iron saccharate i.p. and control group (iron adequate), 0.9% NaCl i.p.; and (ii) iron-deficiency model, induced by repeated bleeding, and control group (sham operated). Proteins were assessed by immunohistochemistry and Western blot. In control mice, DMT1 was localized in the cytoplasm of airway cells, and in iron deficiency and overload it was in the apical membrane. Divalent metal transporter 1 and TfR increased in iron deficiency, without changes in iron overload. ZRT-IRE-like protein 14 decreased in airway cells in iron deficiency and increased in iron overload. In iron deficiency, HFE and FPN were immunolocalized close to the apical membrane

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... blocks the intestine from taking up iron. Other medical conditions Other medical conditions that may lead to iron-deficiency anemia ... daily amount of iron. If you have other medical conditions that cause iron-deficiency anemia , such as ...

Serum iron test

Science.gov (United States)

Fe+2; Ferric ion; Fe++; Ferrous ion; Iron - serum; Anemia - serum iron; Hemochromatosis - serum iron ... A blood sample is needed. Iron levels are highest in the morning. Your health care provider will likely have you do this test in the morning.

Liver Iron Contents in Rats after Administration of Certain Iron ...

African Journals Online (AJOL)

The effect of consumption of certain iron compounds on liver iron deposition was ... extra iron probably depends on the type of food prepared, .... main groups. Each main group consisted of 4 subgroups. (8 rats per subgroup) which received the same basic diet but differing amounts of iron of a specific type. Each animal was ...

Iron Homeostasis in Mycobacterium tuberculosis: Mechanistic Insights into Siderophore-Mediated Iron Uptake

Science.gov (United States)

2016-01-01

Mycobacterium tuberculosis requires iron for normal growth but faces a limitation of the metal ion due to its low solubility at biological pH and the withholding of iron by the mammalian host. The pathogen expresses the Fe3+-specific siderophores mycobactin and carboxymycobactin to chelate the metal ion from insoluble iron and the host proteins transferrin, lactoferrin, and ferritin. Siderophore-mediated iron uptake is essential for the survival of M. tuberculosis, as knockout mutants, which were defective in siderophore synthesis or uptake, failed to survive in low-iron medium and inside macrophages. But as excess iron is toxic due to its catalytic role in the generation of free radicals, regulation of iron uptake is necessary to maintain optimal levels of intracellular iron. The focus of this review is to present a comprehensive overview of iron homeostasis in M. tuberculosis that is discussed in the context of mycobactin biosynthesis, transport of iron across the mycobacterial cell envelope, and storage of excess iron. The clinical significance of the serum iron status and the expression of the iron-regulated protein HupB in tuberculosis (TB) patients is presented here, highlighting the potential of HupB as a marker, notably in extrapulmonary TB cases. PMID:27402628

IRON CONTENT OF FOOD COOKED IN IRON UTENSILS: A TRADITIONAL INDIAN WAY

Directory of Open Access Journals (Sweden)

Bibifatima Bawakhan

2016-08-01

Full Text Available BACKGROUND Since most of the Indian population depends on vegetarian diet, prevalence of iron deficiency status is higher in India compared to other developing countries. In spite of many national programs and treatment options available in correcting this, the incidence is increasing due to poor patient compliance and intolerance to treatment. This study was an effort to show how iron content of Indian food can be increased just by following the traditional way of cooking. OBJECTIVE To compare the iron levels in the Jowar roti cooked in iron and non-iron utensils. METHODOLOGY A cross-sectional study was conducted at KIMS, Hubli. Jowar rotis were prepared from equal quantity of jowar flour in iron and non-iron tawa. Another sample of roti was prepared in iron tawa after treating with lemon juice. Six samples were homogenised and filtered. The filtrates were replicated and analysed for iron levels by FerroZine method. RESULTS In the present study, we found no change in iron levels in the roti prepared in non-iron utensil, 1.45 and 1.94 fold increase in the roti prepared in new iron tawa without water boiled in it and with water boiled in it for dough preparation respectively when compared with iron levels of plain jowar flour. There was 5.77 fold rise in iron levels in lemon juice treated roti which signifies the bioavailability of iron in food. The study showed statistical significance at ‘p’- value < 0.05. CONCLUSION Several studies have shown the similar results and this was done to strengthen the findings in our staple food. Hence, the daily iron requirement can be met easily and effectively by taking the food cooked with lemon juice in iron utensils.

Nutritional iron deficiency

NARCIS (Netherlands)

Zimmermann, M.B.; Hurrell, R.F.

2007-01-01

Iron deficiency is one of the leading risk factors for disability and death worldwide, affecting an estimated 2 billion people. Nutritional iron deficiency arises when physiological requirements cannot be met by iron absorption from diet. Dietary iron bioavailability is low in populations consuming

Compacted graphite iron: Cast iron makes a comeback

Science.gov (United States)

Dawson, S.

1994-08-01

Although compacted graphite iron has been known for more than four decades, the absence of a reliable mass-production technique has resulted in relatively little effort to exploit its operational benefits. However, a proven on-line process control technology developed by SinterCast allows for series production of complex components in high-quality CGI. The improved mechanical properties of compacted graphite iron relative to conventional gray iron allow for substantial weight reduction in gasoline and diesel engines or substantial increases in horsepower, or an optimal combination of both. Concurrent with these primary benefits, CGI also provides significant emissions and fuel efficiency benefits allowing automakers to meet legislated performance standards. The operational and environmental benefits of compacted graphite iron together with its low cost and recyclability reinforce cast iron as a prime engineering material for the future.

Colour Metallography of Cast Iron - Chapter 2: Grey Iron (Ⅱ

Directory of Open Access Journals (Sweden)

Zhou Jiyang

2009-08-01

Full Text Available Cast iron, as a traditional metal material, has advantages of low total cost, good castability and machinability, good wear resistance and low notch sensitivity, and is still facing tough challenge in quality, property and variety of types etc. Experts and engineers studying and producing iron castings all around world extremely concern this serious challenge. Over more than 30 years, a great of research work has been carried out on how to further improve its property, expand its application and combine cast iron technology with some hi-techs (for example, computer technology. Nevertheless, cast iron is a multi-element and multi-phase alloy and has complex and variety of structures and still has great development potential in structure and property. For further studying and developing cast iron, theoretical research work is important promise, and the study on solidification process and control mechanism of graphite morphology is fundamental for improving property of cast iron and developing new type of cast iron. Metallography of cast iron normally includes two sections: liquid phase transformation and solid phase transformation. The book, Colour Metallography of Cast Iron, uses colour metallography technique to study solidification structures of cast irons: graphite, carbides, austenite and eutectics; and focuses on solidification processes. With progress of modern solidification theory, the control of material solidification process becomes important measure for improving traditional materials and developing new materials. Solidification structure not only influences mechanical and physical properties of cast iron, but also affects its internal quality. The book uses a large amount of colour photos to describe the formation of solidification structures and their relations. Crystallization phenomena, which cannot be displayed with traditional metallography, are presented and more phase transformation information is obtained from these colour

Discrepancy between different estimates of the hydrodynamic diameter of polymer-coated iron oxide nanoparticles in solution

International Nuclear Information System (INIS)

Regmi, R.; Gumber, V.; Subba Rao, V.; Kohli, I.; Black, C.; Sudakar, C.; Vaishnava, P.; Naik, V.; Naik, R.; Mukhopadhyay, A.; Lawes, G.

2011-01-01

We have synthesized iron oxide nanoparticles coated with a monolayer of dextran, with molecular weights of the polymer between 5 and 670 kDa. Transmission electron microscopy images confirm that the hard core has a crystalline diameter of approximately 12 nm. The hydrodynamic diameters of these coated nanoparticles in solution measured using dynamical light scattering and estimated from magnetic susceptibility studies vary from near 90 nm for the lightest polymer to 140 nm for the heaviest polymer. Conversely, fluorescence correlation spectroscopy measurements yield a diameter of approximately 55 nm for the 15–20 kDa dextran coated nanoparticles, which is consistent with the expected value estimated from the sum of the hard-core diameter and monolayer dextran coating. We discuss the implications of this discrepancy for applications involving polymer-coated magnetic nanoparticles.

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... peas, tofu, dried fruits, and dark green leafy vegetables. Foods rich in vitamin C, such as oranges, strawberries, ... iron are meat, poultry, fish, and iron-fortified foods that have iron ... green leafy vegetables. You can also take an iron supplement. Follow ...

Iron deficiency anemia

Science.gov (United States)

Anemia - iron deficiency ... iron from old red blood cells. Iron deficiency anemia develops when your body's iron stores run low. ... You may have no symptoms if the anemia is mild. Most of the time, ... slowly. Symptoms may include: Feeling weak or tired more often ...

Iron metabolism and toxicity

International Nuclear Information System (INIS)

Papanikolaou, G.; Pantopoulos, K.

2005-01-01

Iron is an essential nutrient with limited bioavailability. When present in excess, iron poses a threat to cells and tissues, and therefore iron homeostasis has to be tightly controlled. Iron's toxicity is largely based on its ability to catalyze the generation of radicals, which attack and damage cellular macromolecules and promote cell death and tissue injury. This is lucidly illustrated in diseases of iron overload, such as hereditary hemochromatosis or transfusional siderosis, where excessive iron accumulation results in tissue damage and organ failure. Pathological iron accumulation in the liver has also been linked to the development of hepatocellular cancer. Here we provide a background on the biology and toxicity of iron and the basic concepts of iron homeostasis at the cellular and systemic level. In addition, we provide an overview of the various disorders of iron overload, which are directly linked to iron's toxicity. Finally, we discuss the potential role of iron in malignant transformation and cancer

Oral sucrosomial iron versus intravenous iron in anemic cancer patients without iron deficiency receiving darbepoetin alfa: a pilot study.

Science.gov (United States)

Mafodda, Antonino; Giuffrida, D; Prestifilippo, A; Azzarello, D; Giannicola, R; Mare, M; Maisano, R

2017-09-01

Erythropoiesis-stimulating agents (ESAs) are often used in treatment of patients with chemotherapy-induced anemia. Many studies have demonstrated an improved hemoglobin (Hb) response when ESA is combined with intravenous iron supplementation and a higher effectiveness of intravenous iron over traditional oral iron formulations. A new formulation of oral sucrosomial iron featuring an increased bioavailability compared to traditional oral formulations has recently become available and could provide a valid alternative to those by intravenous (IV) route. Our study evaluated the performance of sucrosomial iron versus intravenous iron in increasing hemoglobin in anemic cancer patients receiving chemotherapy and darbepoetin alfa, as well as safety, need of transfusion, and quality of life (QoL). The present study considered a cohort of 64 patients with chemotherapy-related anemia (Hb >8 g/dL iron deficiency, scheduled to receive chemotherapy and darbepoetin. All patients received darbepoetin alfa 500 mcg once every 3 weeks and were randomly assigned to receive 8 weeks of IV ferric gluconate 125 mg weekly or oral sucrosomial iron 30 mg daily. The primary endpoint was to demonstrate the performance of oral sucrosomial iron in improving Hb response, compared to intravenous iron. The Hb response was defined as the Hb increase ≥2 g/dL from baseline or the attainment Hb ≥ 12 g/dL. There was no difference in the Hb response rate between the two treatment arms. Seventy one percent of patients treated with IV iron achieved an erythropoietic response, compared to 70% of patients treated with oral iron. By conventional criteria, this difference is considered to be not statistically significant. There were also no differences in the proportion of patients requiring red blood cell transfusions and changes in QoL. Sucrosomial oral iron was better tolerated. In cancer patients with chemotherapy-related anemia receiving darbepoetin alfa, sucrosomial oral iron provides

Synthesis, characterization and magnetorheological properties of carbonyl iron suspension with superparamagnetic nanoparticles as an additive

International Nuclear Information System (INIS)

Leong, Siti Asma’ Nikmat; Mohd Samin, Pakharuddin; Idris, Ani; Rahman, Azura Hanis A; Mazlan, Saiful Amri

2016-01-01

Magnetorheological (MR) fluids are suspensions of micron-sized particles dispersed in carrier fluid. Due to high density magnetic particles, MR fluids are facing the problem with the instability of the suspension caused by high settling rate. Recently, researches have been conducted on the advantages of using the mixture of magnetic nanoparticles and microparticles, called bidisperse MR fluids. However, even though the sedimentation stability is improved, there is a reduction in dynamic yield stress when the nanoparticle is introduced. In this work, the investigation of magnetic iron nanoparticles (γ-Fe 2 O 3 ) as an additive to magnetic carbonyl iron (CI) suspension has been proposed so as to improve the sedimentation stability and redispersibility, but at the same time enhance the MR performance. The results indicated that the addition of nanoparticles reduced the sedimentation rate, improved redispersibility and enhanced the rheological performance of MR fluids as the particle fill the voids between the microparticles and strengthened the interparticle chains contributing to well-arranged particle structures. (paper)

Obesity alters adipose tissue macrophage iron content and tissue iron distribution.

Science.gov (United States)

Orr, Jeb S; Kennedy, Arion; Anderson-Baucum, Emily K; Webb, Corey D; Fordahl, Steve C; Erikson, Keith M; Zhang, Yaofang; Etzerodt, Anders; Moestrup, Søren K; Hasty, Alyssa H

2014-02-01

Adipose tissue (AT) expansion is accompanied by the infiltration and accumulation of AT macrophages (ATMs), as well as a shift in ATM polarization. Several studies have implicated recruited M1 ATMs in the metabolic consequences of obesity; however, little is known regarding the role of alternatively activated resident M2 ATMs in AT homeostasis or how their function is altered in obesity. Herein, we report the discovery of a population of alternatively activated ATMs with elevated cellular iron content and an iron-recycling gene expression profile. These iron-rich ATMs are referred to as MFe(hi), and the remaining ATMs are referred to as MFe(lo). In lean mice, ~25% of the ATMs are MFe(hi); this percentage decreases in obesity owing to the recruitment of MFe(lo) macrophages. Similar to MFe(lo) cells, MFe(hi) ATMs undergo an inflammatory shift in obesity. In vivo, obesity reduces the iron content of MFe(hi) ATMs and the gene expression of iron importers as well as the iron exporter, ferroportin, suggesting an impaired ability to handle iron. In vitro, exposure of primary peritoneal macrophages to saturated fatty acids also alters iron metabolism gene expression. Finally, the impaired MFe(hi) iron handling coincides with adipocyte iron overload in obese mice. In conclusion, in obesity, iron distribution is altered both at the cellular and tissue levels, with AT playing a predominant role in this change. An increased availability of fatty acids during obesity may contribute to the observed changes in MFe(hi) ATM phenotype and their reduced capacity to handle iron.

The surface layer of austempered ductile iron investment castings properties

Directory of Open Access Journals (Sweden)

D. Myszka

2009-01-01

Full Text Available The article presents a unique process of carbonnitriding and nitriding the precision casting surfaces of austempered ductile iron. The results of the research are pointing that adequate process parameters allow to obtain multiple increase of wear resistance and a significant increase of corrosion resistance. Also, changes of cast microstructure and hardness are presented.

Silane surface modification effects on the electromagnetic properties of phosphatized iron-based SMCs

Science.gov (United States)

Fan, Liang-Fang; Hsiang, Hsing-I.; Hung, Jia-Jing

2018-03-01

It is difficult to achieve homogeneous phosphatized iron powder dispersion in organic resins during the preparation of soft magnetic composites (SMCs). Inhomogeneous iron powder mixing in organic resins generally leads to the formation of micro-structural defects in SMCs and hence causes the magnetic properties to become worse. Phosphatized iron powder dispersion in organic resins can be improved by coating the phosphatized iron powder surfaces with a coupling agent. This study investigated the (3-aminopropyl) triethoxysilane (APTES) surface modification effects on the electromagnetic properties of phosphatized iron-based soft magnetic composites (SMCs). The results showed that the phosphatized iron powder surface can be modified using APTES to improve the phosphatized iron powder and epoxy resin compatibility and hence enhance phosphate iron powder epoxy mixing. The tensile strength, initial permeability, rated current under DC-bias superposition and magnetic loss in SMCs prepared using phosphatized iron powders can be effectively improved using APTES surface modification, which provides a promising candidate for power chip inductor applications.

Iron-biofortified rice improves the iron stores of nonanemic Filipino women.

Science.gov (United States)

Haas, Jere D; Beard, John L; Murray-Kolb, Laura E; del Mundo, Angelita M; Felix, Angelina; Gregorio, Glenn B

2005-12-01

Iron deficiency is endemic in much of the world, and food system-based approaches to eradication may be viable with new plant breeding approaches to increase the micronutrient content in staple crops. It is thought that conventional plant breeding approaches provide varieties of rice that have 400-500% higher iron contents than varieties commonly consumed in much of Asia. The efficacy of consuming high-iron rice was tested during a 9-mo feeding trial with a double-blind dietary intervention in 192 religious sisters living in 10 convents around metro Manila, the Philippines. Subjects were randomly assigned to consume either high-iron rice (3.21 mg/kg Fe) or a local variety of control rice (0.57 mg/kg Fe), and daily food consumption was monitored. The high-iron rice contributed 1.79 mg Fe/d to the diet in contrast to 0.37 mg Fe/d from the control rice. The 17% difference in total dietary iron consumption compared with controls (10.16 +/- 1.06 vs. 8.44 +/- 1.82 mg/d) resulted in a modest increase in serum ferritin (P = 0.10) and total body iron (P = 0.06) and no increase in hemoglobin (P = 0.59). However, the response was greater in nonanemic subjects for ferritin (P = 0.02) and body iron (P = 0.05), representing a 20% increase after controlling for baseline values and daily rice consumption. The greatest improvements in iron status were seen in those nonanemic women who had the lowest baseline iron status and in those who consumed the most iron from rice. Consumption of biofortified rice, without any other changes in diet, is efficacious in improving iron stores of women with iron-poor diets in the developing world.

Iron Supplementation, Response in Iron-Deficiency Anemia: Analysis of Five Trials.

Science.gov (United States)

Okam, Maureen M; Koch, Todd A; Tran, Minh-Ha

2017-08-01

Oral iron-replacement therapy is the mainstay of treatment for iron-deficiency anemia, but it is often poorly tolerated or ineffective. Hemoglobin response at day 14 of oral iron may be useful in assessing whether and when to transition patients from oral to intravenous (IV) iron. Pooled data from 5 randomized trials were analyzed to compare oral and IV iron-replacement therapy for iron-deficiency anemia. Treatment criteria and assignment to oral versus IV iron were defined per protocol; this analysis included only subjects receiving oral iron. Responders were subjects with ≥1.0-g/dL increases in hemoglobin at day 14, and nonresponders were those with smaller increases. Demographic and clinical characteristics were evaluated for association with hemoglobin response at multiple timepoints. Most subjects (72.8%) were classified as responders. The proportion of subjects with hemoglobin increases ≥1.0, ≥2.0, and ≥3.0 g/dL was greatest among those with postpartum anemia, intermediate among those with heavy uterine bleeding or gastrointestinal-related causes of anemia, and lowest among those with other causes; this proportion was also significantly greater among responders than nonresponders. A ≥1.0-g/dL increase in hemoglobin on day 14 most accurately predicted satisfactory overall hemoglobin response to oral iron on day 42/56 (sensitivity 90.1%; specificity 79.3%; positive and negative predictive values of 92.9% and 72.7%, respectively). Iron-replacement therapy improved quality of life and reduced fatigue. Hemoglobin responses <1.0 g/dL at day 14 of oral iron identify subjects with iron-deficiency anemia who should be transitioned to IV iron supplementation. Copyright © 2017 Elsevier Inc. All rights reserved.

Iron homeostasis during pregnancy.

Science.gov (United States)

Fisher, Allison L; Nemeth, Elizabeta

2017-12-01

During pregnancy, iron needs to increase substantially to support fetoplacental development and maternal adaptation to pregnancy. To meet these iron requirements, both dietary iron absorption and the mobilization of iron from stores increase, a mechanism that is in large part dependent on the iron-regulatory hormone hepcidin. In healthy human pregnancies, maternal hepcidin concentrations are suppressed in the second and third trimesters, thereby facilitating an increased supply of iron into the circulation. The mechanism of maternal hepcidin suppression in pregnancy is unknown, but hepcidin regulation by the known stimuli (i.e., iron, erythropoietic activity, and inflammation) appears to be preserved during pregnancy. Inappropriately increased maternal hepcidin during pregnancy can compromise the iron availability for placental transfer and impair the efficacy of iron supplementation. The role of fetal hepcidin in the regulation of placental iron transfer still remains to be characterized. This review summarizes the current understanding and addresses the gaps in knowledge about gestational changes in hematologic and iron variables and regulatory aspects of maternal, fetal, and placental iron homeostasis. © 2017 American Society for Nutrition.

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... also are hoping to determine which iron supplements work best to treat iron-deficiency anemia in children who do not consume the daily recommended amount of iron. Read less Participate in NHLBI Clinical Trials We lead or sponsor many studies related to iron-deficiency anemia. See if you ...

Comparison of response between food supplemented with powdered iron and iron in syrup form for iron deficiency anemia

International Nuclear Information System (INIS)

Ahmed, P.

2003-01-01

Objective: To evaluate and compare the response between food supplemented with iron in powdered and iron in syrup forms for the treatment of iron deficiency anemia in children aged 1-5 years. Results: Over half (51 %) of the patients were between 1-2 years of age. One hundred thirty-two were males and 68 females. Most of the patients belonged to poor socioeconomic class. The iron in powder form was better tolerated than iron syrup as this group witnessed fewer episodes of gastrointestinal disturbances. The rise in mean Hb level after 6 weeks of treatment in group A and B was 1.6 g/dl and 1.9 g/dl respectively. Hemoglobin rise in group B was more than group A but this was statistically non-significant (p>0.05). There was small but significant (p<0.05) rise in serum ferritin in both the groups. There was no significant difference between the two groups for response to the two forms of iron administration. Conclusion: The powdered form of iron is a cost-effective and better tolerated method of iron administration in children and can be considered as an alternate option for the treatment of iron deficiency anemia in children. (author)

Water-dispersible sugar-coated iron oxide nanoparticles. An evaluation of their relaxometric and magnetic hyperthermia properties.

Science.gov (United States)

Lartigue, Lenaic; Innocenti, Claudia; Kalaivani, Thangavel; Awwad, Azzam; Sanchez Duque, Maria del Mar; Guari, Yannick; Larionova, Joulia; Guérin, Christian; Montero, Jean-Louis Georges; Barragan-Montero, Véronique; Arosio, Paolo; Lascialfari, Alessandro; Gatteschi, Dante; Sangregorio, Claudio

2011-07-13

Synthesis of functionalized magnetic nanoparticles (NPs) for biomedical applications represents a current challenge. In this paper we present the synthesis and characterization of water-dispersible sugar-coated iron oxide NPs specifically designed as magnetic fluid hyperthermia heat mediators and negative contrast agents for magnetic resonance imaging. In particular, the influence of the inorganic core size was investigated. To this end, iron oxide NPs with average size in the range of 4-35 nm were prepared by thermal decomposition of molecular precursors and then coated with organic ligands bearing a phosphonate group on one side and rhamnose, mannose, or ribose moieties on the other side. In this way a strong anchorage of the organic ligand on the inorganic surface was simply realized by ligand exchange, due to covalent bonding between the Fe(3+) atom and the phosphonate group. These synthesized nanoobjects can be fully dispersed in water forming colloids that are stable over very long periods. Mannose, ribose, and rhamnose were chosen to test the versatility of the method and also because these carbohydrates, in particular rhamnose, which is a substrate of skin lectin, confer targeting properties to the nanosystems. The magnetic, hyperthermal, and relaxometric properties of all the synthesized samples were investigated. Iron oxide NPs of ca. 16-18 nm were found to represent an efficient bifunctional targeting system for theranostic applications, as they have very good transverse relaxivity (three times larger than the best currently available commercial products) and large heat release upon application of radio frequency (RF) electromagnetic radiation with amplitude and frequency close to the human tolerance limit. The results have been rationalized on the basis of the magnetic properties of the investigated samples.

Iron Oxide as an Mri Contrast Agent for Cell Tracking: Supplementary Issue

Directory of Open Access Journals (Sweden)

Daniel J. Korchinski

2015-01-01

Full Text Available Iron oxide contrast agents have been combined with magnetic resonance imaging for cell tracking. In this review, we discuss coating properties and provide an overview of ex vivo and in vivo labeling of different cell types, including stem cells, red blood cells, and monocytes/macrophages. Furthermore, we provide examples of applications of cell tracking with iron contrast agents in stroke, multiple sclerosis, cancer, arteriovenous malformations, and aortic and cerebral aneurysms. Attempts at quantifying iron oxide concentrations and other vascular properties are examined. We advise on designing studies using iron contrast agents including methods for validation.

Evaluation of umbilical cord mesenchymal stem cells labeling with superparamagnetic iron oxide nanoparticles coated with dextran and complexed with Poly-L-Lysine

International Nuclear Information System (INIS)

Sibov, Tatiana Tais; Mamani, Javier Bustamante; Pavon, Lorena Favaro; Cardenas, Walter Humberto; Gamarra, Lionel Fernel; Miyaki, Liza Aya Mabuchi; Marti, Luciana Cavalheiro; Sardinha, Luiz Roberto; Oliveira, Daniela Mara de

2012-01-01

Objective: The objective of this study was to evaluate the effect of the labeling of umbilical cord vein derived mesenchymal stem cells with superparamagnetic iron oxide nanoparticles coated with dextran and complexed to a non-viral transfector agent transfector poly-L-lysine. Methods: The labeling of mesenchymal stem cells was performed using the superparamagnetic iron oxide nanoparticles/dextran complexed and not complexed to poly-L-lysine. Superparamagnetic iron oxide nanoparticles/dextran was incubated with poly-L-lysine in an ultrasonic sonicator at 37 deg C for 10 minutes for complex formation superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine by electrostatic interaction. Then, the mesenchymal stem cells were incubated overnight with the complex superparamagnetic iron oxide nanoparticles/dextran/poly-L-lysine and superparamagnetic iron oxide nanoparticles/dextran. After the incubation period the mesenchymal stem cells were evaluated by internalization of the complex superparamagnetic iron oxide nanoparticles/dextran/polyL-lysine and superparamagnetic iron oxide nanoparticles/dextran by Prussian Blue stain. Cellular viability of labeled mesenchymal stem cells was evaluated by cellular proliferation assay using 5,6-carboxyfluorescein-succinimidyl ester method and apoptosis detection by Annexin V- Propidium Iodide assay. Results: mesenchymal stem cells labeled with superparamagnetic iron oxide nanoparticles/ dextran without poly-L-lysine not internalized efficiently the superparamagnetic iron oxide nanoparticles due to its low presence detected within cells. Mesenchymal stem cells labeled with the complex superparamagnetic iron oxide nanoparticles/dextran/polyL-lysine efficiently internalized the superparamagnetic iron oxide nanoparticles due to greater presence in the cells interior. The viability and apoptosis assays demonstrated that the mesenchymal stem cells labeled and not labeled respectively with the superparamagnetic iron oxide

Dietary Factors Modulate Iron Uptake in Caco-2 Cells from an Iron Ingot Used as a Home Fortificant to Prevent Iron Deficiency

Directory of Open Access Journals (Sweden)

Ildefonso Rodriguez-Ramiro

2017-09-01

Full Text Available Iron deficiency is a major public health concern and nutritional approaches are required to reduce its prevalence. The aim of this study was to examine the iron bioavailability of a novel home fortificant, the “Lucky Iron Fish™” (LIF (www.luckyironfish.com/shop, Guelph, Canada and the impact of dietary factors and a food matrix on iron uptake from LIF in Caco-2 cells. LIF released a substantial quantity of iron (about 1.2 mM at pH 2 but this iron was only slightly soluble at pH 7 and not taken up by cells. The addition of ascorbic acid (AA maintained the solubility of iron released from LIF (LIF-iron at pH 7 and facilitated iron uptake by the cells in a concentration-dependent manner. In vitro digestion of LIF-iron in the presence of peas increased iron uptake 10-fold. However, the addition of tannic acid to the digestion reduced the cellular iron uptake 7.5-fold. Additionally, LIF-iron induced an overproduction of reactive oxygen species (ROS, similar to ferrous sulfate, but this effect was counteracted by the addition of AA. Overall, our data illustrate the major influence of dietary factors on iron solubility and bioavailability from LIF, and demonstrate that the addition of AA enhances iron uptake and reduces ROS in the intestinal lumen.

In vitro evaluation of iron solubility and dialyzability of various iron fortificants and of iron-fortified milk products targeted for infants and toddlers.

Science.gov (United States)

Kapsokefalou, Maria; Alexandropoulou, Isidora; Komaitis, Michail; Politis, Ioannis

2005-06-01

The objectives of the present study were: to compare the solubility and dialyzability of various iron fortificants (iron pyrophosphate, ferrous bis-glycinate, ferrous gluconate, ferrous lactate, ferrous sulfate) added, in the presence of ascorbic acid, to pasteurized milk samples produced under laboratory conditions; and to compare the solubility and dialyzability of iron in commercial pasteurized, UHT and condensed milk products available in the Greek market fortified with various vitamins and minerals including iron and targeted towards infants (6-12 months old) and toddlers. Iron solubility and dialyzability were determined using a simulated gastrointestinal digestive system. Ferrous dialyzable iron (molecular weight lower than 8000) was used as an index for prediction of iron bioavailability. Ferrous dialyzable iron in pasteurized milk samples fortified with iron pyrophosphate, ferrous lactate and ferrous bis-glycinate was higher (P iron in products fortified with ferrous lactate was not different (P > 0.05) from those fortified with ferrous sulfate. Ferrous dialyzable iron in four condensed commercial milk products was higher (P iron was higher (P iron source, milk processing and the overall product composition affect formation of ferrous dialyzable iron and may determine the success and effectiveness of iron fortification of milk.

Intravenous Iron Therapy in Patients with Iron Deficiency Anemia: Dosing Considerations

Directory of Open Access Journals (Sweden)

Todd A. Koch

2015-01-01

Full Text Available Objective. To provide clinicians with evidence-based guidance for iron therapy dosing in patients with iron deficiency anemia (IDA, we conducted a study examining the benefits of a higher cumulative dose of intravenous (IV iron than what is typically administered. Methods. We first individually analyzed 5 clinical studies, averaging the total iron deficit across all patients utilizing a modified Ganzoni formula; we then similarly analyzed 2 larger clinical studies. For the second of the larger studies (Study 7, we also compared the efficacy and retreatment requirements of a cumulative dose of 1500 mg ferric carboxymaltose (FCM to 1000 mg iron sucrose (IS. Results. The average iron deficit was calculated to be 1531 mg for patients in Studies 1–5 and 1392 mg for patients in Studies 6-7. The percentage of patients who were retreated with IV iron between Days 56 and 90 was significantly (p<0.001 lower (5.6% in the 1500 mg group, compared to the 1000 mg group (11.1%. Conclusions. Our data suggests that a total cumulative dose of 1000 mg of IV iron may be insufficient for iron repletion in a majority of patients with IDA and a dose of 1500 mg is closer to the actual iron deficit in these patients.

Anti frictional materials iron-pig iron-brass manufacture using shaving waste products of pig-iron

International Nuclear Information System (INIS)

Nasamov, S. N.; Krivij, N.; Gudenau, H. W.; Babich, A. I.; Garcia, L. L.; Formoso, A.; Cores, A.

2003-01-01

Parts based on iron and steel powders are widely used in the manufacture of automobile and domestic equipment. This work was done to study the anti-friction properties of iron-pig iron-brass compositions of materials which were obtained by pressing and sintering from a mix of iron powders and industrial by products of cast-iron turnings, brass, talc and technical sulphur. Experiments were performed using cold pressure technology in the flowing matrix of the powder composite without solid lubricants. The subsequent sintering was carried out at 1200 degree centigree under isothermal conditions in a nitrogen atmosphere in the sintering zone during 1 h. The physical-mechanical and anti-friction properties were almost double by the active drainage of the gases from the compression mould. The study of the microstructure of the sintered materials showed that free cementite existed between the particle limits and around the pores. large agglomerations of dark inclusions could be observed, consisting of graphite, zinc and iron oxides, which were points of tension in the materials that reduce its durability and, therefore, its wear resistance to dry friction. (Author) 34 refs

A density functional theory study of the carbon-coating effects on lithium iron borate battery electrodes

DEFF Research Database (Denmark)

Loftager, Simon; García Lastra, Juan Maria; Vegge, Tejs

2017-01-01

a density functional theory (DFT) study of the anchoring configurations of carbon coating on the LiFeBO3 electrode and its implications on the interfacial lithium diffusion. Due to large barriers associated with Li-ion diffusion through a parallel-oriented pristine graphene coating on the FeBO3 and LiFeBO3......Lithium iron borate (LiFeBO3) is a promising cathode material due to its high theoretical specific capacity, inexpensive components and a small volume change during operation. Yet, challenges relating to severe air- and moisture-induced degradation necessitate the application of a protective...... coating on the electrode which also improves the electronic conductivity. However, not much is known about the preferential geometries of the coating as well as how these coating–electrode interfaces influence the lithium diffusion between the coating and the electrode. Here, we therefore present...

Assessment of polyphase sintered iron-cobalt-iron boride cermets

International Nuclear Information System (INIS)

Nowacki, J.; Pieczonka, T.

2004-01-01

Sintering of iron, cobalt and boron powders has been analysed. As a result iron-iron boride, Fe-Fe 2 B and iron/cobalt boride with a slight admixture of molybdenum, Fe - Co - (FeMoCo) 2 B cermets have been produced. Iron was introduced to the mixture as the Astalloy Mo Hoeganaes grade powder. Elemental amorphous boron powder was used, and formation of borides occurred both during heating and isothermal sintering periods causing dimensional changes of the sintered body. Dilatometry was chosen to control basic phenomena taking place during multiphase sintering of investigated systems. The microstructure and phase constituents of sintered compacts were controlled as well. The cermets produced were substituted to: metallographic tests, X-ray analysis, measurements of hardness and of microhardness, and of wear in the process of sliding dry friction. Cermets are made up of two phases; hard grains of iron - cobalt boride, (FeCo) 2 B (1800 HV) constituting the reinforcement and a relatively soft and plastic eutectic mixture Fe 2 B - Co (400-500 HV) constituting the matrix. (author)

Advanced zirconia-coated carbonyl-iron particles for acidic magnetorheological finishing of chemical-vapor-deposited ZnS and other IR materials

Science.gov (United States)

Salzman, S.; Giannechini, L. J.; Romanofsky, H. J.; Golini, N.; Taylor, B.; Jacobs, S. D.; Lambropoulos, J. C.

2015-10-01

We present a modified version of zirconia-coated carbonyl-iron (CI) particles that were invented at the University of Rochester in 2008. The amount of zirconia on the coating is increased to further protect the iron particles from corrosion when introduced to an acidic environment. Five low-pH, magnetorheological (MR) fluids were made with five acids: acetic, hydrochloric, nitric, phosphoric, and hydrofluoric. All fluids were based on the modified zirconia-coated CI particles. Off-line viscosity and pH stability were measured for all acidic MR fluids to determine the ideal fluid composition for acidic MR finishing of chemical-vapor-deposited (CVD) zinc sulfide (ZnS) and other infrared (IR) optical materials, such as hot-isostatic-pressed (HIP) ZnS, CVD zinc selenide (ZnSe), and magnesium fluoride (MgF2). Results show significant reduction in surface artifacts (millimeter-size, pebble-like structures on the finished surface) for several standard-grade CVD ZnS substrates and good surface roughness for the non-CVD MgF2 substrate when MR finished with our advanced acidic MR fluid.

Core-shell iron-iron oxide nanoparticles

DEFF Research Database (Denmark)

Kuhn, Luise Theil; Bojesen, A.; Timmermann, L.

2004-01-01

We present studies of the magnetic properties of core-shell iron-iron oxide nanoparticles. By combining Mossbauer and X-ray absorption spectroscopy we have been able to measure the change from a Fe3O4-like to a gamma-Fe2O3-like composition from the interface to the surface. Furthermore, we have...

Evaluating tamsulosin hydrochloride-released microparticles prepared using single-step matrix coating.

Science.gov (United States)

Maeda, Atsushi; Shinoda, Tatsuki; Ito, Naoki; Baba, Keizo; Oku, Naoto; Mizumoto, Takao

2011-04-15

The objective of the present study was to determine the optimum composition for sustained-release of tamsulosin hydrochloride from microparticles intended for orally disintegrating tablets. Microparticles were prepared from an aqueous ethylcellulose dispersion (Aquacoa®), and an aqueous copolymer based on ethyl acrylate and methyl methacrylate dispersion (Eudragit®) NE30D), with microcrystalline cellulose as core particles with a fluidized bed coating process. Prepared microparticles were about 200 μm diameter and spherical. The microparticles were evaluated for in vitro drug release and in vivo absorption to assess bioequivalence in a commercial product, Harnal® pellets. The optimum ratio of Aquacoat® and Eudragit® NE30D in the matrix was 9:1. We observed similar drug release profiles in microparticles and Harnal® pellets. Higuchi model analysis of the in vitro drug release from microparticles was linear up to 80% release, typical of Fickian diffusion sustained-release profile. The in vivo absorption properties from microparticles were comparable to Harnal® pellets, and there was a linear relationship between in vitro drug release and in vivo drug release. In conclusion, this development produces microparticles in single-step coating, that provided a sustained-release of tamsulosin hydrochloride comparable to Harnal® pellets. Copyright © 2011 Elsevier B.V. All rights reserved.

Assessment of iron deficiency in pregnant women by determining iron status

International Nuclear Information System (INIS)

Raza, N.; Munazza, B.; Ayub, M.; Sarwar, I

2011-01-01

Background: Pregnant women constitute a high risk group for iron deficiency. Maternal iron deficiency and particularly iron deficiency anaemia may be associated with detrimental effects on maternal and infant function and particularly with a higher risk of preterm delivery and delivery of low birth weight neonates. Objective of this study was to assess and compare the iron status of normal healthy non-pregnant women with that of pregnant women of Hazara Division. Methods: This study was conducted at Faculty of Health Sciences, Hazara University, and Ayub Medical College, Abbottabad from first March to /31 August 2006. Altogether 120 women, 90 pregnant at various stages of pregnancy and 30 non-pregnant women as control group were included in this study by convenience sampling. Their iron status was assessed by determination of haemoglobin (Hb), Serum ferritin, Serum-iron, Total Iron Binding Capacity (TIBC), Unsaturated Iron Binding Capacity (UIBC), and Percentage saturation of transferrin. Data generated on these variables were subjected to ANOVA and correlation analysis. Results: The salient finding of this study is a significant decrease in Hb, Serum ferritin, Serum iron, percentage saturation of transferrin and a significant increase in values of TIBC and a pronounced increase in UIBC in second and third trimester compared to first trimester in iron deficient pregnant women. The mean values of Hb, SF, and Fe/TIBC% were significantly lower in the cases than in the control and significantly higher values of TIBC and UIBC were observed in the cases compared to controls. Significant correlations were observed for TIBC, UIBC and Fe/TIBC% against serum iron in different trimesters of pregnancy. Conclusion: A high percentage of the pregnant women are iron deficient due to factors such as high parity, poor dietary habits and socioeconomic status. (author)

Iron

DEFF Research Database (Denmark)

Hansen, Jakob Bondo; Moen, I W; Mandrup-Poulsen, T

2014-01-01

and discuss recent evidence, suggesting that iron is a key pathogenic factor in both type 1 and type 2 diabetes with a focus on inflammatory pathways. Pro-inflammatory cytokine-induced β-cell death is not fully understood, but may include iron-induced ROS formation resulting in dedifferentiation by activation...... of transcription factors, activation of the mitochondrial apoptotic machinery or of other cell death mechanisms. The pro-inflammatory cytokine IL-1β facilitates divalent metal transporter 1 (DMT1)-induced β-cell iron uptake and consequently ROS formation and apoptosis, and we propose that this mechanism provides...

Inhibitory Effect Evaluation of Glycerol-Iron Oxide Thin Films on Methicillin-Resistant Staphylococcus aureus

Directory of Open Access Journals (Sweden)

C. L. Popa

2015-01-01

Full Text Available The main purpose of this study was to evaluate the inhibitory effect of glycerol- iron oxide thin films on Methicillin-Resistant Staphylococcus aureus (MRSA. Our results suggest that glycerol-iron oxide thin films could be used in the future for various biomedical and pharmaceutical applications. The glycerol-iron oxide thin films have been deposited by spin coating method on a silicon (111 substrate. The structural properties have been studied by X-ray diffraction (XRD and scanning electron spectroscopy (SEM. The XRD investigations of the prepared thin films demonstrate that the crystal structure of glycerol-iron oxide nanoparticles was not changed after spin coating deposition. On the other hand, the SEM micrographs suggest that the size of the glycerol-iron oxide microspheres increased with the increase of glycerol exhibiting narrow size distributions. The qualitative depth profile of glycerol-iron oxide thin films was identified by glow discharge optical emission spectroscopy (GDOES. The GDOES spectra revealed the presence of the main elements: Fe, O, C, H, and Si. The antimicrobial activity of glycerol-iron oxide thin films was evaluated by measuring the zone of inhibition. After 18 hours of incubation at 37°C, the diameters of the zones of complete inhibition have been measured obtaining values around 25 mm.

Synthesis, characterization, applications, and challenges of iron oxide nanoparticles

Science.gov (United States)

Ali, Attarad; Zafar, Hira; Zia, Muhammad; ul Haq, Ihsan; Phull, Abdul Rehman; Ali, Joham Sarfraz; Hussain, Altaf

2016-01-01

Recently, iron oxide nanoparticles (NPs) have attracted much consideration due to their unique properties, such as superparamagnetism, surface-to-volume ratio, greater surface area, and easy separation methodology. Various physical, chemical, and biological methods have been adopted to synthesize magnetic NPs with suitable surface chemistry. This review summarizes the methods for the preparation of iron oxide NPs, size and morphology control, and magnetic properties with recent bioengineering, commercial, and industrial applications. Iron oxides exhibit great potential in the fields of life sciences such as biomedicine, agriculture, and environment. Nontoxic conduct and biocompatible applications of magnetic NPs can be enriched further by special surface coating with organic or inorganic molecules, including surfactants, drugs, proteins, starches, enzymes, antibodies, nucleotides, nonionic detergents, and polyelectrolytes. Magnetic NPs can also be directed to an organ, tissue, or tumor using an external magnetic field for hyperthermic treatment of patients. Keeping in mind the current interest in iron NPs, this review is designed to report recent information from synthesis to characterization, and applications of iron NPs. PMID:27578966

Current understanding of iron homeostasis.

Science.gov (United States)

Anderson, Gregory J; Frazer, David M

2017-12-01

Iron is an essential trace element, but it is also toxic in excess, and thus mammals have developed elegant mechanisms for keeping both cellular and whole-body iron concentrations within the optimal physiologic range. In the diet, iron is either sequestered within heme or in various nonheme forms. Although the absorption of heme iron is poorly understood, nonheme iron is transported across the apical membrane of the intestinal enterocyte by divalent metal-ion transporter 1 (DMT1) and is exported into the circulation via ferroportin 1 (FPN1). Newly absorbed iron binds to plasma transferrin and is distributed around the body to sites of utilization with the erythroid marrow having particularly high iron requirements. Iron-loaded transferrin binds to transferrin receptor 1 on the surface of most body cells, and after endocytosis of the complex, iron enters the cytoplasm via DMT1 in the endosomal membrane. This iron can be used for metabolic functions, stored within cytosolic ferritin, or exported from the cell via FPN1. Cellular iron concentrations are modulated by the iron regulatory proteins (IRPs) IRP1 and IRP2. At the whole-body level, dietary iron absorption and iron export from the tissues into the plasma are regulated by the liver-derived peptide hepcidin. When tissue iron demands are high, hepcidin concentrations are low and vice versa. Too little or too much iron can have important clinical consequences. Most iron deficiency reflects an inadequate supply of iron in the diet, whereas iron excess is usually associated with hereditary disorders. These disorders include various forms of hemochromatosis, which are characterized by inadequate hepcidin production and, thus, increased dietary iron intake, and iron-loading anemias whereby both increased iron absorption and transfusion therapy contribute to the iron overload. Despite major recent advances, much remains to be learned about iron physiology and pathophysiology. © 2017 American Society for Nutrition.

Iron and iron-related proteins in asbestosis.

Science.gov (United States)

ABSTRACT: We tested the postulate that iron homeostasis is altered among patients diagnosed to have asbestosis. Lung tissue from six individuals diagnosed to have had asbestosis at autopsy was stained for iron, ferritin, divalent metal transporter 1 (DMT1), and ferroportin 1 (FP...

Glutathione, Glutaredoxins, and Iron.

Science.gov (United States)

Berndt, Carsten; Lillig, Christopher Horst

2017-11-20

Glutathione (GSH) is the most abundant cellular low-molecular-weight thiol in the majority of organisms in all kingdoms of life. Therefore, functions of GSH and disturbed regulation of its concentration are associated with numerous physiological and pathological situations. Recent Advances: The function of GSH as redox buffer or antioxidant is increasingly being questioned. New functions, especially functions connected to the cellular iron homeostasis, were elucidated. Via the formation of iron complexes, GSH is an important player in all aspects of iron metabolism: sensing and regulation of iron levels, iron trafficking, and biosynthesis of iron cofactors. The variety of GSH coordinated iron complexes and their functions with a special focus on FeS-glutaredoxins are summarized in this review. Interestingly, GSH analogues that function as major low-molecular-weight thiols in organisms lacking GSH resemble the functions in iron homeostasis. Since these iron-related functions are most likely also connected to thiol redox chemistry, it is difficult to distinguish between mechanisms related to either redox or iron metabolisms. The ability of GSH to coordinate iron in different complexes with or without proteins needs further investigation. The discovery of new Fe-GSH complexes and their physiological functions will significantly advance our understanding of cellular iron homeostasis. Antioxid. Redox Signal. 27, 1235-1251.

Second international round robin for the quantification of serum non-transferrin-bound iron and labile plasma iron in patients with iron-overload disorders

NARCIS (Netherlands)

de Swart, Louise; Hendriks, Jan C. M.; van der Vorm, Lisa N.; Cabantchik, Z. Ioav; Evans, Patricia J.; Hod, Eldad A.; Brittenham, Gary M.; Furman, Yael; Wojczyk, Boguslaw; Janssen, Mirian C. H.; Porter, John B.; Mattijssen, Vera E. J. M.; Biemond, Bart J.; MacKenzie, Marius A.; Origa, Raffaella; Galanello, Renzo; Hider, Robert C.; Swinkels, Dorine W.

2016-01-01

Non-transferrin-bound iron and its labile (redox active) plasma iron component are thought to be potentially toxic forms of iron originally identified in the serum of patients with iron overload. We compared ten worldwide leading assays (6 for non-transferrin-bound iron and 4 for labile plasma iron)

Iron prophylaxis during pregnancy -- how much iron is needed? A randomized dose- response study of 20-80 mg ferrous iron daily in pregnant women

DEFF Research Database (Denmark)

Milman, Nils; Bergholt, Thomas; Eriksen, Lisbeth

2005-01-01

To determine the lowest dose of iron preventative of iron deficiency and iron deficiency anemia in pregnancy.......To determine the lowest dose of iron preventative of iron deficiency and iron deficiency anemia in pregnancy....

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... from developing iron-deficiency anemia. Foods that are good sources of iron include dried beans, dried fruits, eggs, lean red meat, ... signs of iron-deficiency anemia include: Brittle nails ...

Surface analysis in steel nitrides by using Moessbauer spectroscopy

International Nuclear Information System (INIS)

Figueiredo, R.S. de.

1991-07-01

The formation of iron nitride layer at low temperatures, 600-700 K, by Moessbauer spectroscopy is studied. These layers were obtained basically through two different processes: ion nitriding and ammonia gas nitriding. A preliminary study about post-discharge nitriding was made using discharge in hollow cathode as well as microwave excitation. The assembly of these chambers is also described. The analysis of the nitrided samples was done by CEMS and CXMS, aided by optical microscopy, and the CEMS and CXMS detectors were constructed by ourselves. We also made a brief study about these detectors, testing as acetone as the mixture 80% He+10% C H 4 as detection gases for the use of CEMS. The surface analysis of the samples showed that in the ammonia gas process nitriding the nitrided layer starts by the superficial formation of an iron nitride rich nitrogen. By thermal evolution this nitride promotes the diffusion of nitrogen and the formation of other more stable nitrides. (author)

Cast irons

CERN Document Server

1996-01-01

Cast iron offers the design engineer a low-cost, high-strength material that can be easily melted and poured into a wide variety of useful, and sometimes complex, shapes. This latest handbook from ASM covers the entire spectrum of one of the most widely used and versatile of all engineered materials. The reader will find the basic, but vital, information on metallurgy, solidification characteristics, and properties. Extensive reviews are presented on the low-alloy gray, ductile, compacted graphite, and malleable irons. New and expanded material has been added covering high-alloy white irons used for abrasion resistance and high-alloy graphitic irons for heat and corrosion resistance. Also discussed are melting furnaces and foundry practices such as melting, inoculation, alloying, pouring, gating and rising, and molding. Heat treating practices including stress relieving, annealing, normalizing, hardening and tempering, autempering (of ductile irons), and surface-hardening treatments are covered, too. ASM Spec...

Identification of precipitates formed on zero-valent iron in anaerobic aqueous solutions

International Nuclear Information System (INIS)

Schuhmacher, T.; Odziemkowski, M.S.; Reardon, E.J.; Gillham, R.W.

1997-01-01

The formation of precipitates has been identified as a possible limitation in the use of granular iron for in situ remediation of groundwater. This study was undertaken to identify the precipitates that form on the iron surfaces under conditions of differing water chemistry. Two laboratory column tests were performed using 100 mesh, 99% pure electrolytic iron. A 120 mg/L calcium carbonate (CaCO 3 ) solution passed through one column and a 40 mg/L potassium bromide (KBr) solution through the other. The CaCO, treated iron formed a whitish gray coating on the first centimeter of the column but the KBr treated iron did not display any visible precipitates. X-ray diffraction, Raman spectroscopy, and scanning electron microscopy were used to identify the precipitates. Calcium carbonate and ferrous carbonate (FeCO 3 ) phases were only present on the surface of the iron removed from the influent end of the column treated with a CaCO 3 solution. Iron surfaces analyzed from both the influent and the effluent end of the KBr treated iron and the effluent end of the CaCO 3 treated iron indicated the presence of magnetite (Fe 3 O 4 ) precipitates

Comparison of food habits, iron intake and iron status in adolescents before and after the withdrawal of the general iron fortification in Sweden.

Science.gov (United States)

Sjöberg, A; Hulthén, L

2015-04-01

Sifted flour was fortified with carbonyl iron for 50 years in Sweden. This study evaluates changes in food habits, intake of iron, factors affecting iron absorption and iron status after the discontinuation of the general iron fortification in adolescents with the highest requirements. A total of 2285 15- to 16-year-old students in 1994 (634 girls and 611 boys) and in 2000 (534 girls and 486 boys) in 13 schools in Gothenburg, Sweden, were included in two cross-sectional surveys assessing food habits with diet history interviews and iron deficiency defined with serum ferritin stores ⩽ 15 μg/l and no preceding infection. In girls, iron deficiency increased from 37 to 45%, while in boys, it was stable at 23%. Total iron intake decreased from 15.7 to 9.5 mg/day and 22.5 to 13.9 mg/day in girls and boys, respectively. Cereals were the main iron source. Among girls, the increase of fish and decrease of calcium intake may not counteract the effect of decreased intake of fortification iron. Among boys, more meat, less calcium and more vitamin C may have favoured the bioavailability of iron. The discontinuation of the general iron fortification resulted in a 39% decrease in total iron intake and iron deficiency increased substantially in girls. However, in boys no change in iron deficiency was observed. Whether this was a result of changed bioavailability of dietary iron or simultaneous changes of non-dietary factors remains to be explored.

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... for iron-deficiency anemia. Lifestyle habits Certain lifestyle habits may increase your risk for iron-deficiency anemia, including: Vegetarian or vegan eating patterns. Not eating enough iron-rich foods, such ...

Biogenic iron mineralization at Iron Mountain, CA with implications for detection with the Mars Curiosity rover

Science.gov (United States)

Williams, Amy J.; Sumner, Dawn Y.; Alpers, Charles N.; Campbell, Kate M.; Nordstrom, D. Kirk

2014-01-01

(Introduction) Microbe-mineral interactions and biosignature preservation in oxidized sulfidic ore bodies (gossans) are prime candidates for astrobiological study. Such oxidized iron systems have been proposed as analogs for some Martian environments. Recent studies identified microbial fossils preserved as mineral-coated filaments. This study documents microbially-mediated mineral biosignatures in hydrous ferric oxide (HFO) and ferric oxyhydroxysulfates (FOHS) in three environments at Iron Mountain, CA. We investigated microbial community preservation via HFO and FOHS precipitation and the formation of filamentous mineral biosignatures. These environments included 1) actively precipitating (1000's yrs), naturally weathered HFO from in situ gossan, and 3) remobilized iron deposits, which contained lithified clastics and zones of HFO precipitate. We used published biogenicity criteria as guidelines to characterize the biogenicity of mineral filaments. These criteria included A) an actively precipitating environment where microbes are known to be coated in minerals, B) presence of extant microbial communities with carbon signatures, C) structures observable as a part of the host rock, and D) biological morphology, including cellular lumina, multiple member population, numerous taxa, variable and 3-D preservation, biological size ranges, uniform diameter, and evidence of flexibility. This study explores the relevance and detection of these biosignatures to possible Martian biosignatures. Similar filamentous biosignatures are resolvable by the Mars Hand Lens Imager (MAHLI) onboard the Mars Science Laboratory (MSL) rover, Curiosity, and may be identifiable as biogenic if present on Mars.

Use of radionuclides in the study of iron metabolism in iron deficient states

International Nuclear Information System (INIS)

Anatkov, A.; Karakostov, K.; Iliev, Z.; Dimitrov, L.

1977-01-01

A study of erythropoiesis in iron deficient anemias by simultaneous labelling with the radionuclides iron 59 and chromium 51 revealed accelerated iron circuit, higher percentage of daily hemolysis, severely reduced or even absent labile reserves, decreased volume of packed red cells with no decrease of blood volume. Adequate iron 59 utilization was observed after administration of large doses of iron (500 mg) in the treatment of iron deficient anemias. (author)

Prediction of reducible soil iron content from iron extraction data

NARCIS (Netherlands)

Bodegom, van P.M.; Reeven, van J.; Denier van der Gon, H.A.C.

2003-01-01

Soils contain various iron compounds that differ in solubility, reducibility and extractability. Moreover, the contribution of the various iron compounds to total iron (Fe) and total Fe concentrations differs highly among soils. As a result, the total reducible Fe content can also differ among

Taking iron supplements

Science.gov (United States)

... medlineplus.gov/ency/article/007478.htm Taking iron supplements To use the sharing features on this page, ... levels. You may also need to take iron supplements as well to rebuild iron stores in your ...

Rate and extent of aqueous perchlorate removal by iron surfaces.

Science.gov (United States)

Moore, Angela M; De Leon, Corinne H; Young, Thomas M

2003-07-15

The rate and extent of perchlorate reduction on several types of iron metal was studied in batch and column reactors. Mass balances performed on the batch experiments indicate that perchlorate is initially sorbed to the iron surface, followed by a reduction to chloride. Perchlorate removal was proportional to the iron dosage in the batch reactors, with up to 66% removal in 336 h in the highest dosage system (1.25 g mL(-1)). Surface-normalized reaction rates among three commercial sources of iron filings were similar for acid-washed samples. The most significant perchlorate removal occurred in solutions with slightly acidic or near-neutral initial pH values. Surface mediation of the reaction is supported by the absence of reduction in batch experiments with soluble Fe2+ and also by the similarity in specific reaction rate constants (kSA) determined for three different iron types. Elevated soluble chloride concentrations significantly inhibited perchlorate reduction, and lower removal rates were observed for iron samples with higher amounts of background chloride contamination. Perchlorate reduction was not observed on electrolytic sources of iron or on a mixed-phase oxide (Fe3O4), suggesting that the reactive iron phase is neither pure zerovalent iron nor the mixed oxide alone. A mixed valence iron hydr(oxide) coating or a sorbed Fe2+ surface complex represent the most likely sites for the reaction. The observed reaction rates are too slow for immediate use in remediation system design, but the findings may provide a basis for future development of cost-effective abiotic perchlorate removal techniques.

Iron deficiency anaemia: with the conclusion of a need for iron reader

Science.gov (United States)

Lim, Wai Feng; Yap, Boon Kar; Lai, Mei I.; Talik, Noorazrina; Nasser, Ammar Ahmed; Al-Haiqi, Ahmed Mubarak Ahmed; Sankar Krishnan, Prajindra

2017-10-01

In our bloodstream, there are plenty of red blood cells (RBC), which function as an important oxygen carrier in our bodies. Each RBC consists of millions of haemoglobin (Hb), which is made up from globin and iron. If any deficiency/malfunction of any globin, it will lead to anaemia as indicated in low Hb level while iron deficiency anaemia (IDA) is anaemic due to the lacking of iron as indicated in low Hb and ferritin levels. IDA affects almost two billion people globally while anaemia without iron deficiency, such as thalassaemia, affects almost 4.5% in Malaysian population. These anaemic conditions have similar clinical symptoms like fatigue, dizziness, in which disturb their cognitive development and productivity in workplace. In areas without proper medical access, many anaemic individuals were misdiagnosed and treated with iron tablets because they were thought to have iron deficiency anaemia due to low Hb content. But, excess iron is toxic to the body. Misdiagnosis can be avoided by iron status assessment. We hereby review the currently available iron status parameters in laboratory and field study with the conclusion of demonstrating the importance of a need for iron reader, in the effort to reduce the prevalence of IDA globally.

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... making new blood cells. Visit our Aplastic Anemia Health Topic to learn more. ... recommend that you take iron supplements, also called iron pills or oral iron, by mouth once or several times a ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... ESAs are usually used with iron therapy or IV iron, or when iron therapy alone is not enough. Look for Living With will discuss what your doctor may recommend, including lifelong lifestyle changes ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... breastfeeding. Recommended daily iron intake for children and adults. The table lists the recommended amounts of iron, ... increased need for iron during growth spurts. Older adults, especially those over age 65. Unhealthy environments Children ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... red meat, salmon, iron-fortified breads and cereals, peas, tofu, dried fruits, and dark green leafy vegetables. ... stored iron has been used. Ferritin is a protein that helps store iron in your body. Reticulocyte ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... heart failure . Increased risk of infections Motor or cognitive development delays in children Pregnancy complications, such as ... iron-deficiency anemia may require intravenous (IV) iron therapy or a blood transfusion . Iron supplements Your doctor ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... drinking black tea, which reduces iron absorption. Other treatments If you have chronic kidney disease and iron- ... and lifestyle changes to avoid complications. Follow your treatment plan Do not stop taking your prescribed iron ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... diagnoses you with iron-deficiency anemia, your treatment will depend on the cause and severity of the ... of iron. The recommended daily amounts of iron will depend on your age, sex, and whether you ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... girls. From birth to 6 months, babies need 0.27 mg of iron. This number goes up ... screen blood donors for low iron stores. Reliable point-of-care testing may help identify iron deficiency ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... you do not have enough iron in your body. People with mild or moderate iron-deficiency anemia ... and where to find more information. Causes Your body needs iron to make healthy red blood cells. ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... starch. Restless legs syndrome Shortness of breath Weakness Complications Undiagnosed or untreated iron-deficiency anemia may cause ... as complete blood count and iron studies. Prevent complications over your lifetime To prevent complications from iron- ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... lean red meat, salmon, iron-fortified breads and cereals, peas, tofu, dried fruits, and dark green leafy ... sources of iron, including iron-fortified breads and cereals, beans, tofu, dried fruits, and spinach and other ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... amount of iron, and medical conditions that make it hard for your body to absorb iron from ... hepcidin. Hepcidin prevents iron from leaving cells where it is stored or from being absorbed in the ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... iron-fortified foods that have iron added. Vegetarian diets can provide enough iron if you choose nonmeat ... Anemia in Chronic Kidney Disease (National Institute of Diabetes and Digestive and Kidney Diseases) Avoiding Anemia (National ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... bleeding. If undiagnosed or untreated, iron-deficiency anemia can cause serious complications, including heart failure and development ... iron is too low. Low intake of iron can happen because of blood loss, consuming less than ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... fruits, eggs, lean red meat, salmon, iron-fortified breads and cereals, peas, tofu, dried fruits, and dark ... choose nonmeat sources of iron, including iron-fortified breads and cereals, beans, tofu, dried fruits, and spinach ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... and pregnancy. Good sources of iron are meat, poultry, fish, and iron-fortified foods that have iron ... Anemia Restless Legs Syndrome Von Willebrand Disease Other Resources NHLBI resources Your Guide to Anemia [PDF, 1. ...

Whole-body iron-59 retention measurements for estimating the iron status of piglets

International Nuclear Information System (INIS)

Pfau, A.; Rudolphi, K.; Heinrich, H.C.; Gabbe, E.E.

1976-01-01

A large-volume, 4π whole-body liquid scintillation detector was used to determine 59 Fe absorption in 173 one-to-six-weeks-old piglets with normal and depleted iron stores. Values of intestinal absorption from a 10 μmole (corresponds to 0.558 mg) 59 Fe 2+ test dose were compared with levels of haemoglobin, haematocrit, and serum iron as well as with stainable diffuse iron of bone marrow reticuloendothelial cells, and the dose relationship of intestinal iron absorption from 59 Fe-labelled FeSO 4 and methaemoglobin was measured. The investigations indicated that neither blood parameters, cytochemical gradings nor absorption levels from the 59 Fe test dose alone were sufficient to describe quantitatively the various stages of iron deficiency in piglets. A synopsis of all parameters appeared to be necessary for defining normal iron status and prelatent, latent and manifest iron deficiency. Piglets fed on sows' milk only developed manifest iron deficiency within the first three weeks of age. After an access to soil and/or creep feed from the eighth day of age, or intramuscular injections of 200 mg Fe as iron-dextran at three days of age, or injections of 200 or 400 mg Fe combined with access to creep feed, stages of manifest, latent or prelatent iron deficiency could be observed. For an iron-dextran dose of 800 mg Fe injected in amounts of 400 mg Fe at 3 and 10 days of age, a normal iron status was obtained in three-week-old piglets. The iron dose relationship indicated that 20 mg Fe administered orally as FeSO 4 or 40 mg Fe as methaemoglobin-Fe daily should cover the iron requirement of piglets for the first three weeks of life, whereas a three-week total of iron given orally in a single dose would lead to unphysiological or fatal conditions in nursing pigs. (author)

Cellular iron transport.

Science.gov (United States)

Garrick, Michael D; Garrick, Laura M

2009-05-01

Iron has a split personality as an essential nutrient that also has the potential to generate reactive oxygen species. We discuss how different cell types within specific tissues manage this schizophrenia. The emphasis in enterocytes is on regulating the body's supply of iron by regulating transport into the blood stream. In developing red blood cells, adaptations in transport manage the body's highest flux of iron. Hepatocytes buffer the body's stock of iron. Macrophage recycle the iron from effete red cells among other iron management tasks. Pneumocytes provide a barrier to prevent illicit entry that, when at risk of breaching, leads to a need to handle the dangers in a fashion essentially shared with macrophage. We also discuss or introduce cell types including renal cells, neurons, other brain cells, and more where our ignorance, currently still vast, needs to be removed by future research.

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... because your body’s intake of iron is too low. Low intake of iron can happen because of blood ... delivery or giving birth to a baby with low birth weight In people with chronic conditions, iron- ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... for iron-deficiency anemia if you have certain risk factors , including pregnancy. To prevent iron-deficiency anemia, your doctor may recommend you eat heart-healthy foods or control other conditions that can cause iron-deficiency anemia. ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... blood cells. Iron-deficiency anemia usually develops over time because your body’s intake of iron is too ... clamping of your newborn’s umbilical cord at the time of delivery. This may help prevent iron-deficiency ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... severity of the condition. Your doctor may recommend healthy eating changes, iron supplements, intravenous iron therapy for mild ... you: Adopt healthy lifestyle changes such as heart-healthy eating patterns. Increase your daily intake of iron-rich ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... different ages and stages of life. Until the teen years, the recommended amount of iron is the ... cow’s milk. Cow’s milk is low in iron. Teens, who have increased need for iron during growth ...

Antimony Adsorption from Zarshouran Gold Mineral Processing Plant Wastewater by Nano Zero Valent Iron Coated on Bentonite

Directory of Open Access Journals (Sweden)

nader nosrati

2015-03-01

Full Text Available The effluent from Zarshouran gold mineral processing plant contains high quantities of arsenic, antimony, mercury, and bismuth. These metals and metalloids are soluble in water and very toxic when they enter the environment. Their solubility in water causes the polluted area to extend beyond their point of origin. In this article, different methods of antimony removal from water and wastewater were reviewed and the zero-valent iron nanoparticles coated on Bentonite were selected as an effective and low cost material for removing antimony from wastewater. For the purposes of this study, zero-valent iron nanoparticles of 40-100 nanometers in size were synthesized by dropwise addition of sodium borohydride solution to an Iron (III aqueous solution at  ambient temperature and mixed with nitrogen gas. To avoid particle agglomeration and to enhance the product’s environmentally safe application, the  nanoparticles were coated on Bentonite and characterized by SEM/EDAX and BET. The experiments were carried out by intense mixing of the adsorbent with 10ml of real/synthtic wastewater samples in 20ml bottles.  The effects of pH, contact time, temperature, and adsorbent dosage on antimony removal efficiency were investigated under intense mixing using a magnetic mixer. Finally, the effluents were filtered upon completion of the experiments and used for atomic adsorption analysis. The results of the experiments showed that the adsorption isotherms of the synthesized nanoparticles obeyed the Langmuir and Freundlich models. The experiments carried out on real samples showed that antimony adsorption capacity for B-nZVI was 2.6 mg/g of the adsorbent and that the highest antimony removal efficiency was 99.56%.

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... iron, in milligrams (mg) at different ages and stages of life. Until the teen years, the recommended amount of ... and choosing iron-rich foods, especially during certain stages of life when more iron is needed, such as childhood ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... because your body’s intake of iron is too low. Low intake of iron can happen because of blood ... a lot of cow’s milk. Cow’s milk is low in iron. Teens, who have increased need for ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... for iron-deficiency anemia. Lifestyle habits Certain lifestyle habits may increase your risk for iron-deficiency anemia, including: Vegetarian or vegan eating patterns. Not eating enough iron-rich foods, such as meat and fish, may result in ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... bleeding or other abnormalities, such as growths or cancer of the lining of the colon. For this test, a ... that you take iron supplements, also called iron pills or oral iron, by mouth once or several times a ...

Iron-57 and iridium-193 Moessbauer spectroscopic studies of supported iron-iridium catalysts

International Nuclear Information System (INIS)

Berry, F.J.; Jobson, S.

1988-01-01

57 Fe and 193 Ir Moessbauer spectroscopy shows that silica- and alumina-supported iron-iridium catalysts formed by calcination in air contain mixtures of small particle iron(III) oxide and iridium(IV) oxide. The iridium dioxide in both supported catalysts is reduced in hydrogen to metallic iridium. The α-Fe 2 O 3 in the silica supported materials is predominantly reduced in hydrogen to an iron-iridium alloy whilst in the alumina-supported catalyst the iron is stabilised by treatment in hydrogen as iron(II). Treatment of a hydrogen-reduced silica-supported iron catalyst in hydrogen and carbon monoxide is accompanied by the formation of iron carbides. Carbide formation is not observed when the iron-iridium catalysts are treated in similar atmospheres. The results from the bimetallic catalysts are discussed in terms of the hydrogenation of associatively adsorbed carbon monoxide and the selectivity of supported iron-iridium catalysts to methanol formation. (orig.)

Nicotianamine synthase overexpression positively modulates iron homeostasis-related genes in high iron rice

Directory of Open Access Journals (Sweden)

Meng eWang

2013-05-01

Full Text Available Nearly one-third of the world population, mostly women and children, suffer from iron malnutrition and its consequences, such as anemia or impaired mental development. Biofortification of rice, which is a staple crop for nearly half of the world’s population, can significantly contribute in alleviating iron deficiency. NFP rice (transgenic rice expressing nicotianamine synthase, ferritin and phytase genes has a more than six-fold increase in iron content in polished rice grains, resulting from the synergistic action of nicotianamine synthase (NAS and ferritin transgenes. We investigated iron homeostasis in NFP plants by analyzing the expression of 28 endogenous rice genes known to be involved in the homeostasis of iron and other metals, in iron-deficient and iron-sufficient conditions. RNA was collected from different tissues (roots, flag leaves, grains and at three developmental stages during grain filling. NFP plants showed increased sensitivity to iron-deficiency conditions and changes in the expression of endogenous genes involved in nicotianamine (NA metabolism, in comparison to their non-transgenic siblings. Elevated transcript levels were detected in NFP plants for several iron transporters. In contrast, expression of OsYSL2, which encodes a member of Yellow Stripe-like protein family, and a transporter of the NA-Fe(II complex was reduced in NFP plants under low iron conditions, indicating that expression of OsYSL2 is regulated by the endogenous iron status. Expression of the transgenes did not significantly affect overall iron homeostasis in NFP plants, which establishes the engineered push-pull mechanism as a suitable strategy to increase rice endosperm iron content.

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... anemia, your doctor may order the following blood tests to diagnose iron-deficiency anemia: Complete blood count (CBC) to ... than normal when viewed under a microscope. Different tests help your doctor diagnose iron-deficiency anemia. In iron-deficiency anemia, blood ...

Competing ferromagnetic and anti-ferromagnetic interactions in iron nitride ζ-Fe2N

Science.gov (United States)

Rao, K. Sandeep; Salunke, H. G.

2018-03-01

The paper discusses the magnetic state of zeta phase of iron nitride viz. ζ-Fe2N on the basis of spin polarized first principles electronic structure calculations together with a review of already published data. Results of our first principles study suggest that the ground state of ζ-Fe2N is ferromagnetic (FM) with a magnetic moment of 1.528μB on the Fe site. The FM ground state is lower than the anti-ferromagnetic (AFM) state by 8.44 meV and non-magnetic (NM) state by 191 meV per formula unit. These results are important in view of reports which claim that ζ-Fe2N undergoes an AFM transition below 10 K and others which do not observe any magnetic transition up to 4.2 K. We argue that the experimental results of AFM transition below 10 K are inconclusive and we propose the presence of competing FM and AFM superexchange interactions between Fe sites mediated by nitrogen atoms, which are consistent with Goodenough-Kanamori-Anderson rules. We find that the anti-ferromagnetically coupled Fe sites are outnumbered by ferromagnetically coupled Fe sites leading to a stable FM ground state. A Stoner analysis of the results also supports our claim of a FM ground state.

Characterization of plasma nitrided layers produced on sintered iron

Directory of Open Access Journals (Sweden)

Marcos Alves Fontes

2014-07-01

Full Text Available Plasma nitriding is a thermo-physical-chemical treatment process, which promotes surface hardening, caused by interstitial diffusion of atomic nitrogen into metallic alloys. In this work, this process was employed in the surface modification of a sintered ferrous alloy. Scanning electron microscopy (SEM, X-ray diffraction (XRD analyses, and wear and microhardness tests were performed on the samples submitted to ferrox treatment and plasma nitriding carried out under different conditions of time and temperature. The results showed that the nitride layer thickness is higher for all nitrided samples than for ferrox treated samples, and this layer thickness increases with nitriding time and temperature, and temperature is a more significant variable. The XRD analysis showed that the nitrided layer, for all samples, near the surface consists in a mixture of γ′-Fe4N and ɛ-Fe3N phases. Both wear resistance and microhardness increase with nitriding time and temperature, and temperature influences both the characteristics the most.

Efficacy of iron supplementation may be misinterpreted using conventional measures of iron status in iron-depleted, nonanemic women undergoing aerobic exercise training.

Science.gov (United States)

Pompano, Laura M; Haas, Jere D

2017-12-01

Background: Despite its known detrimental effects, iron deficiency remains the most common micronutrient deficiency in the world. Many interventions that aim to improve iron status involve physically active populations. Intense aerobic exercise training negatively affects iron status; however, the impact of regular moderate aerobic exercise on the effectiveness of iron supplementation remains unclear. Objective: This study aimed to determine whether aerobic training modifies the assessment of the effectiveness of iron supplementation in improving conventional iron status measures. Design: Seventy-two iron-depleted, nonanemic Chinese women [serum ferritin (sFer) 110 g/L] were included in an 8-wk, partially blinded, randomized controlled trial with a 2 × 2 factorial design including iron supplements (42 mg elemental Fe/d) or placebo and aerobic training (five 25-min sessions/wk at 75-85% of maximum heart rate) or no training. Linear mixed models were used to evaluate the relation between supplement type, training, and changes in iron status over time, measured by sFer, hemoglobin, soluble transferrin receptor (sTfR), and estimated total body iron. Results: After treatment, both the iron-supplemented trained and untrained groups showed significantly improved sFer, sTfR, and body iron values compared with either of the placebo groups. Similarly, trained participants had significantly higher aerobic fitness measures than untrained participants. Training modified the sFer response to supplementation (training by supplement interaction, P = 0.07), with the iron-supplemented trained group having significantly lower sFer than the iron-supplemented untrained group at week 8 (mean ± SD: 31.8 ± 13.5 and 47.6 ± 15.7 μg/L, respectively; P = 0.042), whereas there was no significant difference between the placebo trained and untrained groups (21.3 ± 12.2 and 20.3 ± 7.0 μg/L, respectively; P = 1.00). Conclusions: Regular aerobic training reduces the apparent effectiveness

Changes in serum iron, total iron binding capacity and transferrin ...

African Journals Online (AJOL)

Background: Iron is a vital constituent of cells but in excess may be harmful and is associated with a raised risk for some malignant diseases including breast cancer. We aimed to study changes in iron profile in Sudanese females newly diagnosed with breast cancer. Methods: A case- control study in which serum iron, Total ...

49 CFR 192.487 - Remedial measures: Distribution lines other than cast iron or ductile iron lines.

Science.gov (United States)

2010-10-01

... cast iron or ductile iron lines. 192.487 Section 192.487 Transportation Other Regulations Relating to... iron or ductile iron lines. (a) General corrosion. Except for cast iron or ductile iron pipe, each... the purpose of this paragraph. (b) Localized corrosion pitting. Except for cast iron or ductile iron...

The role of mitochondria in cellular iron-sulfur protein biogenesis and iron metabolism.

Science.gov (United States)

Lill, Roland; Hoffmann, Bastian; Molik, Sabine; Pierik, Antonio J; Rietzschel, Nicole; Stehling, Oliver; Uzarska, Marta A; Webert, Holger; Wilbrecht, Claudia; Mühlenhoff, Ulrich

2012-09-01

Mitochondria play a key role in iron metabolism in that they synthesize heme, assemble iron-sulfur (Fe/S) proteins, and participate in cellular iron regulation. Here, we review the latter two topics and their intimate connection. The mitochondrial Fe/S cluster (ISC) assembly machinery consists of 17 proteins that operate in three major steps of the maturation process. First, the cysteine desulfurase complex Nfs1-Isd11 as the sulfur donor cooperates with ferredoxin-ferredoxin reductase acting as an electron transfer chain, and frataxin to synthesize an [2Fe-2S] cluster on the scaffold protein Isu1. Second, the cluster is released from Isu1 and transferred toward apoproteins with the help of a dedicated Hsp70 chaperone system and the glutaredoxin Grx5. Finally, various specialized ISC components assist in the generation of [4Fe-4S] clusters and cluster insertion into specific target apoproteins. Functional defects of the core ISC assembly machinery are signaled to cytosolic or nuclear iron regulatory systems resulting in increased cellular iron acquisition and mitochondrial iron accumulation. In fungi, regulation is achieved by iron-responsive transcription factors controlling the expression of genes involved in iron uptake and intracellular distribution. They are assisted by cytosolic multidomain glutaredoxins which use a bound Fe/S cluster as iron sensor and additionally perform an essential role in intracellular iron delivery to target metalloproteins. In mammalian cells, the iron regulatory proteins IRP1, an Fe/S protein, and IRP2 act in a post-transcriptional fashion to adjust the cellular needs for iron. Thus, Fe/S protein biogenesis and cellular iron metabolism are tightly linked to coordinate iron supply and utilization. This article is part of a Special Issue entitled: Cell Biology of Metals. Copyright © 2012 Elsevier B.V. All rights reserved.

Ironing Out the Unconventional Mechanisms of Iron Acquisition and Gene Regulation in Chlamydia

Directory of Open Access Journals (Sweden)

Nick D. Pokorzynski

2017-09-01

Full Text Available The obligate intracellular pathogen Chlamydia trachomatis, along with its close species relatives, is known to be strictly dependent upon the availability of iron. Deprivation of iron in vitro induces an aberrant morphological phenotype termed “persistence.” This persistent phenotype develops in response to various immunological and nutritional insults and may contribute to the development of sub-acute Chlamydia-associated chronic diseases in susceptible populations. Given the importance of iron to Chlamydia, relatively little is understood about its acquisition and its role in gene regulation in comparison to other iron-dependent bacteria. Analysis of the genome sequences of a variety of chlamydial species hinted at the involvement of unconventional mechanisms, being that Chlamydia lack many conventional systems of iron homeostasis that are highly conserved in other bacteria. Herein we detail past and current research regarding chlamydial iron biology in an attempt to provide context to the rapid progress of the field in recent years. We aim to highlight recent discoveries and innovations that illuminate the strategies involved in chlamydial iron homeostasis, including the vesicular mode of acquiring iron from the intracellular environment, and the identification of a putative iron-dependent transcriptional regulator that is synthesized as a fusion with a ABC-type transporter subunit. These recent findings, along with the noted absence of iron-related homologs, indicate that Chlamydia have evolved atypical approaches to the problem of iron homeostasis, reinvigorating research into the iron biology of this pathogen.

Effect of the number of iron oxide nanoparticle layers on the magnetic properties of nanocomposite LbL assemblies

International Nuclear Information System (INIS)

Dincer, Ilker; Tozkoparan, Onur; German, Sergey V.; Markin, Alexey V.; Yildirim, Oguz; Khomutov, Gennady B.; Gorin, Dmitry A.; Venig, Sergey B.; Elerman, Yalcin

2012-01-01

Aqueous colloidal suspension of iron oxide nanoparticles has been synthesized. Z-potential of iron oxide nanoparticles stabilized by citric acid was −35±3 mV. Iron oxide nanoparticles have been characterized by the light scattering method and transmission electron microscopy. The polyelectrolyte/iron oxide nanoparticle thin films with different numbers of iron oxide nanoparticle layers have been prepared on the surface of silicon substrates via the layer-by-layer assembly technique. The physical properties and chemical composition of nanocomposite thin films have been studied by atomic force microscopy, magnetic force microscopy, magnetization measurements, Raman spectroscopy. Using the analysis of experimental data it was established, that the magnetic properties of nanocomposite films depended on the number of iron oxide nanoparticle layers, the size of iron oxide nanoparticle aggregates, the distance between aggregates, and the chemical composition of iron oxide nanoparticles embedded into the nanocomposite films. The magnetic permeability of nanocomposite coatings has been calculated. The magnetic permeability values depend on the number of iron oxide nanoparticle layers in nanocomposite film. - Highlights: ► The magnetic properties of nanocomposite films depended on the number of iron oxide nanoparticle layers. ► The iron oxide nanoparticle phase in nanocomposite coatings is a mixture of magnetite and maghemite phases. ► The magnetite and maghemite phases depend on a number of iron oxide nanoparticle layers because the iron oxide nanoparticles are oxidized from magnetite to maghemite.

Iron-Air Rechargeable Battery

Science.gov (United States)

Narayan, Sri R. (Inventor); Prakash, G.K. Surya (Inventor); Kindler, Andrew (Inventor)

2014-01-01

Embodiments include an iron-air rechargeable battery having a composite electrode including an iron electrode and a hydrogen electrode integrated therewith. An air electrode is spaced from the iron electrode and an electrolyte is provided in contact with the air electrode and the iron electrodes. Various additives and catalysts are disclosed with respect to the iron electrode, air electrode, and electrolyte for increasing battery efficiency and cycle life.

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... supplements. Iron supplements can change how certain medicines work. Your doctor may suggest check-ups to make sure your ... To prevent complications from iron-deficiency anemia, your doctor may ... during certain stages of life when more iron is needed, such as childhood ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... if you are diagnosed with iron-deficiency anemia. Risk Factors You may have an increased risk for iron-deficiency anemia because of your age, ... or sex. Age You may be at increased risk for iron deficiency at certain ages: Infants between ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... normally stores but has used up. Increase your intake of vitamin C to help your body absorb iron. Avoid drinking black tea, which reduces iron absorption. Other treatments If you have chronic kidney disease and iron-deficiency anemia, your doctor may recommend ...

Determination of Iron Content in Iron Deficiency Drugs by UV-Visible Spectrophotometer

Directory of Open Access Journals (Sweden)

Isam Eldin Hussein Elgailani

2017-07-01

Full Text Available The objective of this work was to validate a simple, precise and accurate spectrophotometric method for the determination of iron in the iron deficiency drugs, namely are Feroglobin B12, Ferose-F and Ferose. The proposed method is based on the reaction of iron with ammonium thiocyanate after the wet digestion of the drugs under study with HNO3 and H2O2.  Effects of pH, temperature, standing time and thiocyanate concentration on the determination of iron in drugs containing iron have been investigated. The λmax was 430 nm and the molar absorptivity of 0.0399 L mol-1 cm-1. The linear regression was in the range 0.5 - 60 μg/mL for iron content in hemoglobin. The detection limit and the limit of quantification were found to be 0.040 and 0.122 µg mL-1 for the iron respectively, and with a linear regression correlation coefficient of 0.998. Recovery measurements ranged from 99.63-100.20%. This method is simple and fast can be used for the determination of iron in the iron deficiency drugs in pharmaceutical laboratories. DOI: http://dx.doi.org/10.17807/orbital.v9i3.953

On iron radionuclide interactions and in situ measurement of iron corrosion products

International Nuclear Information System (INIS)

Puranen, A.; Jonsson, M.; Cui, D.; Scheidegger, A.M.; Wersin, P.; Spahiu, K.

2005-01-01

Full text of publication follows: In performance assessments of hard rock repositories, it is conservatively assumed that waste canisters are breached and that the spent fuel will get into contact with groundwater after 1000 years. When the canister eventually fails to protect HLW from groundwater, dissolved radionuclides from HLW will react with iron canister materials. The reactivity will depend on the conditions in solution and at the iron-water interface. To improve our understanding on the redox chemistry at near field conditions, batch experiments are conducted by contacting polished iron foils with a synthetic groundwater solution containing 10 mM NaCl, 2 mM NaHCO 3 and 5 ppm Se(IV), Se(VI), Tc(VII) and U(VI) in a glove box filled with Ar + 0.03% CO 2 gas mixture. The reaction rates are measured by analysing Se, Tc and U concentrations by ICP-MS. Iron corrosion products formed during the reaction(s) is monitored in-situ by a Layer Raman spectrometer through an optical window. The corrosion potential of the iron foil as well as the Eh and pH values of the bulk solution are recorded continuously during the experiment. The reacted iron foil is embedded with EPOXY resin, and the cross section will be analysed by SEM-EDS and XAS. The preliminary experimental results shows that with the formation of iron green rust FeII 4 FeIII 2 (OH) 12 CO 3 on iron foil, the rates of redox reactions between iron and the negatively charged radionuclides species are increased. The observation is explained by the fact that radionuclide anionic species can be first adsorbed then reduced on the positively charged outer surface of iron green rust. The positive charge is a result of the electrical balance of the negative charges of carbonate contained between the layered iron hydroxides in the green rust. Reduced forms of radionuclides are identified in the iron corrosion products. The results suggest that the formation of iron green rust as a corrosion product on the surface of iron

Colour Metallography of Cast Iron - Chapter 3: Spheroidal Graphite Cast Iron (Ⅳ

Directory of Open Access Journals (Sweden)

Zhou Jiyang

2010-11-01

Full Text Available Cast iron, as a traditional metal material, has advantages of low total cost, good castability and machinability, good wear resistance and low notch sensitivity, and is still facing tough challenge in quality, property and variety of types etc. Experts and engineers studying and producing iron castings all around world extremely concern this serious challenge. Over more than 30 years, a great of research work has been carried out on how to further improve its property, expand its application and combine cast iron technology with some hi-techs (for example, computer technology. Nevertheless, cast iron is a multi-element and multi-phase alloy and has complex and variety of structures and still has great development potential in structure and property. For further studying and developing cast iron, theoretical research work is important promise, and the study on solidification process and control mechanism of graphite morphology is fundamental for improving property of cast iron and developing new type of cast iron. Metallography of cast iron normally includes two sections: liquid phase transformation and solid phase transformation. The book, Colour Metallography of Cast Iron, uses colour metallography technique to study solidification structures of cast irons: graphite, carbides, austenite and eutectics; and focuses on solidification processes. With progress of modern solidification theory, the control of material solidification process becomes important measure for improving traditional materials and developing new materials. Solidification structure not only influences mechanical and physical properties of cast iron, but also affects its internal quality. The book uses a large amount of colour photos to describe the formation of solidification structures and their relations. Crystallization phenomena, which cannot be displayed with traditional metallography, are presented and more phase transformation information is obtained from these colour

Colour Metallography of Cast Iron - Chapter 3: Spheroidal Graphite Cast Iron (Ⅰ

Directory of Open Access Journals (Sweden)

Zhou Jiyang

2010-02-01

Full Text Available Cast iron, as a traditional metal material, has advantages of low total cost, good castability and machinability, good wear resistance and low notch sensitivity, and is still facing tough challenge in quality, property and variety of types etc. Experts and engineers studying and producing iron castings all around world extremely concern this serious challenge. Over more than 30 years, a great of research work has been carried out on how to further improve its property, expand its application and combine cast iron technology with some hi-techs (for example, computer technology. Nevertheless, cast iron is a multi-element and multi-phase alloy and has complex and variety of structures and still has great development potential in structure and property. For further studying and developing cast iron, theoretical research work is important promise, and the study on solidification process and control mechanism of graphite morphology is fundamental for improving property of cast iron and developing new type of cast iron. Metallography of cast iron normally includes two sections: liquid phase transformation and solid phase transformation. The book, Colour Metallography of Cast Iron, uses colour metallography technique to study solidification structures of cast irons: graphite, carbides, austenite and eutectics; and focuses on solidification processes. With progress of modern solidification theory, the control of material solidification process becomes important measure for improving traditional materials and developing new materials. Solidification structure not only influences mechanical and physical properties of cast iron, but also affects its internal quality. The book uses a large amount of colour photos to describe the formation of solidification structures and their relations. Crystallization phenomena, which cannot be displayed with traditional metallography, are presented and more phase transformation information is obtained from these colour

Colour Metallography of Cast Iron - Chapter 4: Vermicular Graphite Cast Iron (Ⅱ

Directory of Open Access Journals (Sweden)

Zhou Jiyang

2011-05-01

Full Text Available Cast iron, as a traditional metal material, has advantages of low total cost, good castability and machinability, good wear resistance and low notch sensitivity, and is still facing tough challenge in quality, property and variety of types etc. Experts and engineers studying and producing iron castings all around world extremely concern this serious challenge. Over more than 30 years, a great of research work has been carried out on how to further improve its property, expand its application and combine cast iron technology with some hi-techs (for example, computer technology. Nevertheless, cast iron is a multi-element and multi-phase alloy and has complex and variety of structures and still has great development potential in structure and property. For further studying and developing cast iron, theoretical research work is important promise, and the study on solidification process and control mechanism of graphite morphology is fundamental for improving property of cast iron and developing new type of cast iron. Metallography of cast iron normally includes two sections: liquid phase transformation and solid phase transformation. The book, Colour Metallography of Cast Iron, uses colour metallography technique to study solidification structures of cast irons: graphite, carbides, austenite and eutectics; and focuses on solidification processes. With progress of modern solidification theory, the control of material solidification process becomes important measure for improving traditional materials and developing new materials. Solidification structure not only influences mechanical and physical properties of cast iron, but also affects its internal quality. The book uses a large amount of colour photos to describe the formation of solidification structures and their relations. Crystallization phenomena, which cannot be displayed with traditional metallography, are presented and more phase transformation information is obtained from these colour

The obtaining of iron acetate from processed iron comprising catalyst of ammonia synthesis

International Nuclear Information System (INIS)

Mansurov, M.M.; Lugovenko, A.N.; Mirzoeva, M.M.

1993-01-01

Present article is devoted to obtaining of iron acetate from processed iron comprising catalyst of ammonia synthesis. The method of synthesis of iron acetate from processed iron comprising catalyst of ammonia synthesis was elaborated. The structure of complex was determined.

Effect of Al doping on phase formation and thermal stability of iron nitride thin films

Energy Technology Data Exchange (ETDEWEB)

Tayal, Akhil [Amity Center for Spintronic Materials, Amity University, Sector 125, Noida 201 303 (India); Gupta, Mukul, E-mail: mgupta@csr.res.in [Amity Center for Spintronic Materials, Amity University, Sector 125, Noida 201 303 (India); Pandey, Nidhi [Amity Center for Spintronic Materials, Amity University, Sector 125, Noida 201 303 (India); Gupta, Ajay [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore 452 001 (India); Horisberger, Michael [Laboratory for Developments and Methods, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland); Stahn, Jochen [Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)

2015-11-25

In the present work, we systematically studied the effect of Al doping on the phase formation of iron nitride (Fe–N) thin films. Fe–N thin films with different concentration of Al (Al = 0, 2, 3, 6, and 12 at.%) were deposited using dc magnetron sputtering by varying the nitrogen partial pressure between 0 and 100%. The structural and magnetic properties of the films were studied using x-ray diffraction and polarized neutron reflectivity. It was observed that at the lowest doping level (2 at.% of Al), nitrogen rich non-magnetic Fe–N phase gets formed at a lower nitrogen partial pressure as compared to the un-doped sample. Interestingly, we observed that as Al doping is increased beyond 3 at.%, nitrogen rich non-magnetic Fe–N phase appears at higher nitrogen partial pressure as compared to un-doped sample. The thermal stability of films were also investigated. Un-doped Fe–N films deposited at 10% nitrogen partial pressure possess poor thermal stability. Doping of Al at 2 at.% improves it marginally, whereas, for 3, 6 and 12 at.% Al doping, it shows significant improvement. The obtained results have been explained in terms of thermodynamics of Fe–N and Al–N. - Highlights: • Doping effects of Al on Fe–N phase formation is studied. • Phase formation shows a non-monotonic behavior with Al doping. • Low doping levels of Al enhance and high levels retard the nitridation process. • Al doping beyond 3 at.% improve thermal stability of Fe–N films.

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... Topics News & Resources Intramural Research Home / < Back To Health Topics / Iron-Deficiency Anemia Iron-Deficiency Anemia Also known as Leer ... and symptoms as well as complications from iron-deficiency anemia. Research for Your Health The NHLBI is part of the U.S. Department ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... iron-deficiency anemia, including: Vegetarian or vegan eating patterns. Not eating enough iron-rich foods, such as meat and fish, may result in you getting less than the recommended daily amount of iron. Frequent blood donation. Individuals who donate blood often may be ...

Iron oxide nanoparticles for use in contrast agents in magnetic resonance imaging

International Nuclear Information System (INIS)

Oliveira, Elisa M.N. de; Rocha, Maximiliano S. da; Caimi, Priscila de A.; Basso, Nara R. de S.; Zanini, Mara L.; Papaleo, Ricardo M.

2015-01-01

In this work were carried out synthesis of iron oxide nanoparticles coated with dextran, comparing the results of using different concentrations of dextran, iron salts, temperature and reaction time. The compounds were analyzed by DLS, XRD, TGA, TEM, FTIR, Zeta Potential and relaxivity. Nanoparticles with dispersion around 10-15 nm and average hydrodynamic diameters of 16-50 nm, with superparamagnetic behavior were obtained. The ratio of the relaxivities (r2/r1) in aqueous solutions was 5.30, close to value of the commercially available iron oxide contrast agents. (author)

Interactions of benzoic acid and phosphates with iron oxide colloids using chemical force titration.

Science.gov (United States)

Liang, Jana; Horton, J Hugh

2005-11-08

Colloidal iron oxides are an important component in soil systems and in water treatment processes. Humic-based organic compounds, containing both phenol and benzoate functional groups, are often present in these systems and compete strongly with phosphate species for binding sites on the iron oxide surfaces. Here, we examine the interaction of benzoate and phenolic groups with various iron oxide colloids using atomic force microscopy (AFM) chemical force titration measurements. Self-assembled monolayers (SAMs) of 4-(12-mercaptododecyloxy)benzoic acid and 4-(12-mercaptododecyloxy)phenol were used to prepare chemically modified Au-coated AFM tips, and these were used to probe the surface chemistry of a series of iron oxide colloids. The SAMs formed were also characterized using scanning tunneling microscopy, reflection-absorption infrared spectroscopy, and X-ray photoelectron spectroscopy. The surface pK(a) of 4-(12- mercaptododecyloxy)benzoic acid has been determined to be 4.0 +/- 0.5, and the interaction between the tip and the sample coated with a SAM of this species is dominated by hydrogen bonding. The chemical force titraton profile for an AFM probe coated with 4-(12- mercaptododecyloxy)benzoic acid and a bare iron oxide colloid demonstrates that the benzoic acid function group interacts with all three types of iron oxide sites present on the colloid surface over a wide pH range. Similar experiments were carried out on colloids precipitated in the presence of phosphoric, gallic, and tannic acids. The results are discussed in the context of the competitive binding interactions of solution species present in soils or in water treatment processes.

Cytosolic iron chaperones: Proteins delivering iron cofactors in the cytosol of mammalian cells.

Science.gov (United States)

Philpott, Caroline C; Ryu, Moon-Suhn; Frey, Avery; Patel, Sarju

2017-08-04

Eukaryotic cells contain hundreds of metalloproteins that are supported by intracellular systems coordinating the uptake and distribution of metal cofactors. Iron cofactors include heme, iron-sulfur clusters, and simple iron ions. Poly(rC)-binding proteins are multifunctional adaptors that serve as iron ion chaperones in the cytosolic/nuclear compartment, binding iron at import and delivering it to enzymes, for storage (ferritin) and export (ferroportin). Ferritin iron is mobilized by autophagy through the cargo receptor, nuclear co-activator 4. The monothiol glutaredoxin Glrx3 and BolA2 function as a [2Fe-2S] chaperone complex. These proteins form a core system of cytosolic iron cofactor chaperones in mammalian cells. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Iron absorption from beans with different contents of iron, evaluated by stable isotopes.

Science.gov (United States)

Junqueira-Franco, Márcia Varella Morandi; Dutra de Oliveira, José Eduardo; Nutti, Marilia Regini; Pereira, Helton Santos; Carvalho, José Luiz Vianna de; Abrams, Steven A; Brandão, Camila Fernanda Cunha; Marchini, Júlio Sérgio

2018-06-01

The introduction of biofortified foods such as beans with higher iron content may be a useful tool in preventing iron deficiency. The biofortification aims to reach the root of the problem of malnutrition, targets the neediest population, uses embedded distribution mechanisms, is scientifically feasible and effective in terms of cost, and complements other ongoing interventions to control micronutrient deficiency. However, to ensure effectiveness, measurement of the absorption of minerals is essential. The objective of this study was to evaluate the iron bioavailability of common bean BRS Pontal (PO), targeted for biofortification, compared with common bean BRS Estilo in man through reliable techniques that have not been previously used in Brazil. The study included 29 young adult volunteers divided into 2 groups: Group CB (13 subjects) received 100 g of common beans (BRS-Estilo) cooked labeled with iron-58 ( 58 Fe) and Group TBB (16 patients) received 100 g common bean target for iron biofortification (BRS-Pontal), cooked and labeled with iron58 ( 58 Fe). The next day they received the reference dose of ferrous sulfate enriched iron-57 ( 57 Fe). Isotopic evaluation of iron for measurement of iron incorporation into erythrocytes was performed 14 days after consumption. The beans used, were produced, through conventional breeding program, by EMBRAPA/Rice and Beans. The iron absorption was evaluated by assessing the isotopic enrichment of the stable isotope. Mean iron absorption from the meal with common beans was 0.409% (±0.040%) and mean iron incorporation from the meal with target beans for biofortification 0.407% (±0.038%) and did not differ between the groups. This study tested the iron absorption from a single bean meal in healthy volunteers or non anemics, In the present study the iron absorption ratio from common bean Pontal (PO), targeted for biofortification and compared with common bean BRS Estilo was not significantly different. The iron concentration

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... This is sometimes used to deliver iron through a blood vessel to increase iron levels in the blood. One benefit of IV iron ... over 65 years of age had low hemoglobin levels. This was associated with a greater risk of death even with mild anemia. ...

Iron and Immunity

NARCIS (Netherlands)

Verbon, E.H.|info:eu-repo/dai/nl/413534049; Trapet, P.L.; Stringlis, I.|info:eu-repo/dai/nl/41185206X; Kruijs, Sophie; Bakker, P.A.H.M.|info:eu-repo/dai/nl/074744623; Pieterse, C.M.J.|info:eu-repo/dai/nl/113115113

2017-01-01

Iron is an essential nutrient for most life on Earth because it functions as a crucial redox catalyst in many cellular processes. However, when present in excess iron can lead to the formation of harmful hydroxyl radicals. Hence, the cellular iron balance must be tightly controlled. Perturbation of

49 CFR 192.369 - Service lines: Connections to cast iron or ductile iron mains.

Science.gov (United States)

2010-10-01

... 49 Transportation 3 2010-10-01 2010-10-01 false Service lines: Connections to cast iron or ductile iron mains. 192.369 Section 192.369 Transportation Other Regulations Relating to Transportation... ductile iron mains. (a) Each service line connected to a cast iron or ductile iron main must be connected...

Investigation of Iron Aluminide Weld Overlays

Energy Technology Data Exchange (ETDEWEB)

Banovic, S.W.; DuPont, J.B.; Levin, B.F.; Marder, A.R.

1999-08-02

Conventional fossil fired boilers have been retrofitted with low NO(sub)x burners in order for the power plants to comply with new clean air regulations. Due to the operating characteristics of these burners, boiler tube sulfidation corrosion typically has been enhanced resulting in premature tube failure. To protect the existing panels from accelerated attack, weld overlay coatings are typically being applied. By depositing an alloy that offers better corrosion resistance than the underlying tube material, the wastage rates can be reduced. While Ni-based and stainless steel compositions are presently providing protection, they are expensive and susceptible to failure via corrosion-fatigue due to microsegregation upon solidification. Another material system presently under consideration for use as a coating in the oxidation/sulfidation environments is iron-aluminum. These alloys are relatively inexpensive, exhibit little microsegregation, and show excellent corrosion resistance. However, their use is limited due to weldability issues and their lack of corrosion characterization in simulated low NO(sub)x gas compositions. Therefore a program was initiated in 1996 to evaluate the use of iron-aluminum weld overlay coatings for erosion/corrosion protection of boiler tubes in fossil fired boilers with low NO(sub)x burners. Investigated properties included weldability, corrosion behavior, erosion resistance, and erosion-corrosion performance.

Tribology of nitrided-coated steel-a review

Directory of Open Access Journals (Sweden)

Bhaskar Santosh V.

2017-01-01

Full Text Available Surface engineering such as surface treatment, coating, and surface modification are employed to increase surface hardness, minimize adhesion, and hence, to reduce friction and improve resistance to wear. To have optimal tribological performance of Physical Vapor Deposition (PVD hard coating to the substrate materials, pretreatment of the substrate materials is always advisable to avoid plastic deformation of the substrate, which may result in eventual coating failure. The surface treatment results in hardening of the substrate and increase in load support effect. Many approaches aim to improve the adhesion of the coatings onto the substrate and nitriding is the one of the best suitable options for the same. In addition to tribological properties, nitriding leads to improved corrosion resistance. Often corrosion resistance is better than that obtainable with other surface engineering processes such as hard-chrome and nickel plating. Ability of this layer to withstand thermal stresses gives stability which extends the surface life of tools and other components exposed to heat. Most importantly, the nitrogen picked-up by the diffusion layer increases the rotating-bending fatigue strength in components. The present article reviews mainly the tribological advancement of different nitrided-coated steels based on the types of coatings, structure, and the tribo-testing parameters, in recent years.

Tribology of nitrided-coated steel-a review

Science.gov (United States)

Bhaskar, Santosh V.; Kudal, Hari N.

2017-01-01

Surface engineering such as surface treatment, coating, and surface modification are employed to increase surface hardness, minimize adhesion, and hence, to reduce friction and improve resistance to wear. To have optimal tribological performance of Physical Vapor Deposition (PVD) hard coating to the substrate materials, pretreatment of the substrate materials is always advisable to avoid plastic deformation of the substrate, which may result in eventual coating failure. The surface treatment results in hardening of the substrate and increase in load support effect. Many approaches aim to improve the adhesion of the coatings onto the substrate and nitriding is the one of the best suitable options for the same. In addition to tribological properties, nitriding leads to improved corrosion resistance. Often corrosion resistance is better than that obtainable with other surface engineering processes such as hard-chrome and nickel plating. Ability of this layer to withstand thermal stresses gives stability which extends the surface life of tools and other components exposed to heat. Most importantly, the nitrogen picked-up by the diffusion layer increases the rotating-bending fatigue strength in components. The present article reviews mainly the tribological advancement of different nitrided-coated steels based on the types of coatings, structure, and the tribo-testing parameters, in recent years.

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... iron-fortified breads and cereals, peas, tofu, dried fruits, and dark green leafy vegetables. Foods rich in vitamin C, such as oranges, ... iron-fortified breads and cereals, beans, tofu, dried fruits, and spinach and other dark green leafy vegetables. You can also take an iron supplement. Follow ...

Iron-Deficiency Anemia

Medline Plus

Full Text Available ... Topics section only, or the News and Resources section. NHLBI Entire Site NHLBI Entire Site Health ... español Iron-deficiency anemia is a common type of anemia that occurs if you do not have enough iron in your body. People with mild or moderate iron-deficiency anemia ...

Effect of treatment with single total-dose intravenous iron versus daily oral iron(III-hydroxide polymaltose on moderate puerperal iron-deficiency anemia

Directory of Open Access Journals (Sweden)

Iyoke CA

2017-05-01

Full Text Available Chukwuemeka Anthony Iyoke,1 Fausta Chioma Emegoakor,1 Euzebus Chinonye Ezugwu,1 Lucky Osaheni Lawani,2 Leonard Ogbonna Ajah,1 Jude Anazoeze Madu,3 Hyginus Uzo Ezegwui,1 Frank Okechukwu Ezugwu4 1Department of Obstetrics and Gynaecology, University of Nigeria, Enugu Campus, 2Department of Obstetrics and Gynaecology, Federal Teaching Hospital, Abakaliki, 3Department of Haematology, University of Nigeria, Nsukka, 4Department of Obstetrics and Gynaecology, College of Medicine, Enugu State University, Enugu, Nigeria Background: Iron-deficiency anemia is the most common nutritional cause of anemia in pregnancy and is often responsible for puerperal anemia. Puerperal anemia can impair postpartum maternal and neonatal well-being. Objective: To determine the effect of treatment of moderate puerperal iron-deficiency anemia using a single intravenous total-dose iron dextran versus daily single dose oral iron(III-hydroxide polymaltose. Methodology: A randomized controlled study in which postpartum women with moderate iron-deficiency anemia were randomized into treatment with either a single total-dose intravenous iron dextran or with daily single doses of oral iron(III-hydroxide polymaltose tablets for 6 weeks. Effects on hemoglobin concentration using either method were compared at 6 weeks postpartum. Analysis was per protocol using SPSS version 17 for windows. P-values ≤0.05 were considered significant. Results: Two hundred eighty-four women were recruited for the study: 142 women received single total dose intravenous infusion of iron dextran while 142 received daily oral iron(III-hydroxide polymaltose tablets. Approximately 84.0% (237/282 completed the study and were analyzed including 81% (115/142 of those randomized to injectable iron therapy compared to 85.9% (122/142 of those randomized to oral treatment. The proportions of women who had attained hemoglobin concentration of at least 10 g/dL by the 6 weeks postpartum visit did not differ

The effect of nutrition knowledge and dietary iron intake on iron status in young women.

Science.gov (United States)

Leonard, Alecia J; Chalmers, Kerry A; Collins, Clare E; Patterson, Amanda J

2014-10-01

Previous research on the relationships between general nutrition knowledge and dietary intake, and dietary iron intake and iron status has produced inconsistent results. Currently, no study has focused on knowledge of dietary iron and its effect on dietary iron intake. This study aimed to determine whether nutrition knowledge of iron is related to dietary iron intake in young women, and subsequently whether greater knowledge and intake translates into better iron status. A cross-sectional assessment of nutrition knowledge of iron, dietary iron intake and iron status was conducted in women aged 18-35 years living in Newcastle, NSW, Australia. Iron status was assessed by serum ferritin, haemoglobin, soluble transferrin receptor and alpha-1-glycoprotein. One hundred and seven women (27.8 ± 4.7 years) completed the nutrition knowledge questionnaire and FFQ. Of these, 74 (70%) also had biomarkers of iron status measured. Mean iron intake was 11.2 ± 3.8 mg/day. There was no association between nutrition knowledge score and whether the women met the RDI for iron (F (1, 102) = .40, P = .53). A positive correlation was shown between nutrition knowledge score and iron intake (mg/day) (r = 0.25, P = .01). Serum ferritin was positively associated with the frequency of flesh food intake (r = .27 P = .02). Vegetarians (including partial vegetarians) had significantly lower serum ferritin levels than non-vegetarians (F (1, 71) = 7.44, P = .01). Significant positive correlations found between higher flesh food intake and biomarkers of iron status suggest that educating non-vegetarians about the benefits of increased flesh food consumption and vegetarians about dietary iron enhancers and inhibitors may have potential for addressing the high rates of iron deficiency among young women. Crown Copyright © 2014. Published by Elsevier Ltd. All rights reserved.

Combined Therapy of Iron Chelator and Antioxidant Completely Restores Brain Dysfunction Induced by Iron Toxicity

Science.gov (United States)

Sripetchwandee, Jirapas; Pipatpiboon, Noppamas; Chattipakorn, Nipon; Chattipakorn, Siriporn

2014-01-01

Background Excessive iron accumulation leads to iron toxicity in the brain; however the underlying mechanism is unclear. We investigated the effects of iron overload induced by high iron-diet consumption on brain mitochondrial function, brain synaptic plasticity and learning and memory. Iron chelator (deferiprone) and antioxidant (n-acetyl cysteine) effects on iron-overload brains were also studied. Methodology Male Wistar rats were fed either normal diet or high iron-diet consumption for 12 weeks, after which rats in each diet group were treated with vehicle or deferiprone (50 mg/kg) or n-acetyl cysteine (100 mg/kg) or both for another 4 weeks. High iron-diet consumption caused brain iron accumulation, brain mitochondrial dysfunction, impaired brain synaptic plasticity and cognition, blood-brain-barrier breakdown, and brain apoptosis. Although both iron chelator and antioxidant attenuated these deleterious effects, combined therapy provided more robust results. Conclusion In conclusion, this is the first study demonstrating that combined iron chelator and anti-oxidant therapy completely restored brain function impaired by iron overload. PMID:24400127

Intravenous iron treatments for iron deficiency anemia in inflammatory bowel disease: a budget impact analysis of iron isomaltoside 1000 (Monofer) in the UK.

Science.gov (United States)

Pollock, R F; Muduma, G

2017-12-01

Iron deficiency is the leading cause of anemia in patients with inflammatory bowel disease (IBD). Intravenous iron is the first-line treatment for clinically active IBD or previous oral iron intolerance. The aim of the present study was to develop a comparative model of iron deficiency and delivery for iron isomaltoside (IIM), ferric carboxymaltose (FCM), low molecular weight iron dextran (LMWID), and iron sucrose (IS) in the treatment of iron deficiency anemia associated with IBD. Areas covered: A model was developed to evaluate iron delivery characteristics, resource use and costs associated with IIM, FCM, LMWID and IS. Iron deficiency was modeled using dosing tables and retreatments were modeled based on a pooled retrospective analysis. The analyses were conducted over 5 years in patients with IBD with mean bodyweight of 75.4 kg and hemoglobin levels of 10.77 g/dL based on observational data. Expert opinion: The modeling analysis showed that using IIM required 1.2 infusions (per treatment) to correct the mean iron deficit, compared with 1.6, 1.2, and 7.1 with FCM, LMWID and IS, respectively. Costs were estimated to be 2,518 pounds sterling (GBP) per patient with IIM or LMWID, relative to GBP 3,309 with FCM or GBP 14,382 with IS.

Bioavailability & absorption of Iron and Anemia

Directory of Open Access Journals (Sweden)

Radhika Kapil

2018-01-01

Full Text Available Humans derive iron from their everyday diet, predominantly from plant foods and the rest from foods of animal origin. Iron is found in food as either haem or non-haem iron.  Haem iron, which is about up to 40 per cent of the iron in meat, poultry, and fish, is well absorbed.  All the iron in plants (fruits, vegetables, grains, nuts is in the form of non-haem iron and is relatively poorly absorbed. Non-haem iron contributes about 90-95 per cent of total daily iron in vegan diets. In western countries,the intake of haem iron from meat and meat products accounts for bulk of the dietary iron. The haem iron consumption is minimal in developing countries with majority obtaining non-haem iron from cereals, pulses, vegetables and fruits'. The diets is plagued by low iron content and poor absorption. Major sources of non-haem iron are plant foods. The iron is chemically diverse, ranging from simple iron oxides and salts to more complex organic chelates such as hydroxyphosphates in phytoferritin(1.

Bioavailability & absorption of Iron and Anemia

Directory of Open Access Journals (Sweden)

Radhika Kapil

2017-12-01

Full Text Available Humans derive iron from their everyday diet, predominantly from plant foods and the rest from foods of animal origin. Iron is found in food as either haem or non-haem iron.  Haem iron, which is about up to 40 per cent of the iron in meat, poultry, and fish, is well absorbed.  All the iron in plants (fruits, vegetables, grains, nuts is in the form of non-haem iron and is relatively poorly absorbed. Non-haem iron contributes about 90-95 per cent of total daily iron in vegan diets. In western countries,the intake of haem iron from meat and meat products accounts for bulk of the dietary iron. The haem iron consumption is minimal in developing countries with majority obtaining non-haem iron from cereals, pulses, vegetables and fruits'. The diets is plagued by low iron content and poor absorption. Major sources of non-haem iron are plant foods. The iron is chemically diverse, ranging from simple iron oxides and salts to more complex organic chelates such as hydroxyphosphates in phytoferritin(1.

Efficacy of iron fortification compared to iron supplementation among Vietamese schoolchildren

NARCIS (Netherlands)

Le, Huong T.; Brouwer, I.D.; Burema, J.; NGuyen, K.C.; Kok, F.J.

2006-01-01

The effect of iron fortification is generally assumed to be less than iron supplementation; however, the magnitude of difference in effects is not known. The present study aims to compare the efficacy of these two strategies on anaemia and iron status. After screening on low Hb, 425 anaemic children

Nitrate-dependent iron oxidation limits iron transport in anoxic ocean regions

DEFF Research Database (Denmark)

Scholz, Florian; Löscher, Carolin; Fiskal, Annika

2016-01-01