Reduction Characteristics and Kinetics of Bayanobo Complex Iron Ore Carbon Bearing Pellets

The kinetics of isothermal reduction of the carbon bearing pellets, which were mainly composed of Bayanobo complex iron ore and pulverized coal, was investigated by thermogravimetry at the temperature of 1 273-1 673 K. The effects of xC/xO and the atmospheres on the extent of reduction also were investigated. The results indicate that the fractional reaction increased proportionally with temperature increasing and heating temperature is the significant influence factor to the reaction of carbon bearing pellets. The optimum xC/xO is 1.2 and the effect of atmosphere on the reduction of iron oxides is almost negligible. The results can be interpreted that the reaction was initially controlled by a mixed controlled mechanism of carbon gasification and interface chemical reaction, and in the later stage, interface chemical reaction became the rate-controlling step. Apparent activation energy values of reduction at different levels of fractional reaction were calculated. Before F （fraction of reaction）=0.5, the apparent activation energy ranges from 66.39 to 75.64 kJ/mol, while after F=0.5, the apparent activation energy is 80.98 to 85.37 kJ/mol.

An analytical method for Fe(Ⅱ) and Fe(Ⅲ) determination in pharmaceutical grade iron sucrose complex and sodium ferric gluconate complex

A robust voltammetric method has been developed and validated for the determination of Fe（Ⅱ） and Fe（Ⅲ） in pharmaceutical iron polysaccharidic complexes. Undesirable low molecular weight iron complexes, at concentration about 3% in the pharmaceutical formulation, can be easily determined with good accuracy and precision. This methodology can be proposed as a viable, environmentally sustainable substitute for the conventional Normal Pulse Polarographic method in US Pharmacopeia, with better analytical figures of merit, and reduced Hg consumption. A deeper insight in Fe（Ⅱ） and Fe（Ⅲ） composition can be gained by the combined use of a new potentiometric technique after chemical decomposition of the complex.

Catalytic performance of cerium iron complex oxides for partial oxidation of methane to synthesis gas

The cerium iron complex oxides oxygen carrier was prepared by the co-precipitation method. The reactions between methane and lattice oxygen from the complex oxides were investigated in a fixed micro-reactor system. The reduced oxygen carder could be re-oxidized by air and its initial state could be restored. The characterizations of the oxygen carders were studied using XRD, O2-TPD, and H2-TPR. The results showed that the bulk lattice oxygen of CeO2-Fe2O3 was found to be suitable for the partial oxidation of methane to synthesis gas. There were two kinds of oxygen species on the oxygen carrier： the stronger oxygen species that was responsible for the complete oxidation of methane, and the weaker oxygen species （bulk lattice oxygen） that was responsible for the selective oxidation of methane to CO and H2 at a higher temperature. Then, the lost bulk lattice oxygen could be selectively supplemented by air re-oxidation at an appropriate reaction condition. CeFeO3 appeared on the oxygen carrier after 10 successive redox cycles, however, it was not bad for the selectivity of CO and H2.

CHARACTERIZATION OF IRON COMPLEXES SUPPORTED ON POLYMER AND THEIR CATALYTIC ACTIVITY IN BUTADIENE POLYMERIZATION

Styrene-acrylic acid copolymer (SAAC)-supported iron complex (SAAC·Fe)was characterized and the effect of the characteristic parameters on the catalytic activity of the complex was investigated. IR spectrum suggested that the complex SAAC·Fe possesses a structure of(C)and the Fe-O bond is higher in covalency.The complex SAAC·Fe with the structure of(C)shoved a higher catalytic activity in butadiene polymerization. When Fe/-COOH molar ratio in SAAC·Fe was about 0.2 the complex gave optimum catalytic activity. The catalytic activity of SAAC·Fe with the higher content of long sequence of acrylic acid units was low. When the content of the short sequence of acrylic acid units was predominant and at the same time the content of the short sequence was approximately equal to that of the long sequence for stryrene, the activity of the complex was high.

Synthesis and Structure of Iron Complex with 1,2-Dithiolate-1,2-dicarba-closo-dodecaborane [Li(THF)_4][Fe(S_2C_2B_10H_10)_2(THF)]

The crystal of complex [Li(THF)4][Fe(S2C2B10H10)2(THF)] 3 belongs to monoclinic, space group P21 with a = 11.964(2), b = 16.527(3), c = 12.554(3) ? = 108.70(3)? V = 2351.3(8) 3, Z = 2, Mr = 835.95, Dc = 1.181 g/cm3, (MoK? = 5.30 cm1, F(000) = 874, R = 0.0622 and Rw = 0.1538 for 1641 observed reflections with I > 2(I). The ionic complex of 3 contains the square pyramidal anion of [Fe(S2C2B10H10)2(THF)] and the tetrahedral cation of [Li(THF)4]+. The iron is 5-coordinated and located in the square pyramidal configuration. The iron atom and the four sulfur atoms are almost coplanar. The Lithium atom is coordinated with four oxygen atoms of four THF molecules and located in a tetrahedral configuration.

Preparation and Identification of Angelica sinensis Polysaccharide-iron Complex

Angelica sinensis polysaccharide（ASP） was extracted from Angelica sinensis by boiling water. An Angelica sinensis polysaccharide-iron complex（APC） was prepared under the alkaline condition by adding a ferric chloride solution to the ASP solution. Then some identifiable properties of the complex were studied. The content of iron（ Ⅲ ） in the complex was determined with iodometry. The thermal property, the microscopic structure, the spectral characteristics, and N, C, H contents of the complex were examined by a variety of techniques including DSC, TEM, IR, NMR, and elemental analysis. The content of iron（ Ⅲ ） in the complex ranges from 10% to 40%. The DSC result shows that the melting point of the complex is about 450 ℃. The TEM result shows that the complex has an iron（ Ⅲ ） core（β-FeOOH core） linked by hydroxy and oxy bridges, with the polysaccharide chains attached to the surface of the core. The IR and NMR results also show that there is a β-FeOOH core in the complex. The elemental analysis shows that the contents of N, C, H in the complex are, respectively, lower than those of N, C, H in ASP. All our studies indicate that the APC consists of a β-FeOOH core surrounded by ASP.

Influence of shape anisotropy on microwave complex permeability in carbonyl iron flakes/epoxy resin composites

To explore the mechanism of carbonyl iron flake composites for microwave complex permeability, this paper investigates the feature of the flakes. The shape anisotropy was certified by the results of the magnetization hysteresis loops and the Mossbauer spectra. Furthermore, the shape anisotropy was used to explain the origin of composite microwave performance, and the calculated results agree with the experiment. It is believed that the shape anisotropy dominates microwave complex permeability, and the natural resonance plays main role in flake.

Synthesis, Crystal Structure, and Magnetic Properties of a New Dinuclear Iron Complex with Schiff Base Ligand

A new dinuclear iron（Ill） complex has been synthesized and structurally charac- terized by X-ray crystallography： [Fem2（L）（C6HsCOO）（SO4）（CH3OH）2]·CH3CN＇CH3OH （1, H3L = N,N＇-bis（salicylidene）q,3-diamino-2-propanol）. Complex 1 belongs to orthorhombic space group Pna21 with a= 11.4400（8）, b = 22.9705（2）, c = 12.5712（9）A, V= 3303.5（4）A3, Z= 4, F（000） = 1576, Dc= 1.531 g·cm-3, Mr= 761.36,μ = 1.007 mm-1, S = 1.014, the final R= 0.0505 and wR= 0.1018. The crystal packing is stabilized by intermolecular O-H…O hydrogen bonds, forming an extended one-dimensional chain structure. The temperature dependence of magnetic susceptibility measurement shows that antiferromagnetic interaction is propagated between the metal centers. Fit as dinuclear arrangement gave parameters ofJ= 19.7 cm-1, g = 1.89 and R2 = 0.9999.

Synthesis, Crystal Structure and Magnetic Properties of a One-dimensional Loop-like Iron(Ⅱ) Complex:[Fe(Haip)_2(H_2O)_2]_n (Haip = 5-Ammoniumisophthalato)

An iron（Ⅱ） coordination polymer, [Fe（Haip）2（H2O）2]n （1, Haip = 5-ammoniumiso- phthalato）, has been hydro/solvothermally synthesized and characterized by single-crystal X-ray diffraction, elemental analysis, infrared spectrum and magnetic measurement. Compound 1 crystalizes in monoclinic, space group P2/c with a = 6.9874（14）, b = 9.960（2）, c = 12.894（4） A, β = 117.47（2）°, Fe（C8H6NO4）2（H2O）2, Mr = 452.16, V= 796.2（3） A3, Z = 2, Dc = 1.886 g.cm-3, p = 1.017 mm-1, F（000） = 464.0, 2.71〈0〈28.42°, R = 0.0307, wR = 0.0840 and S = 1.005. Single-crystal X-ray diffraction analysis reveals that 1 features an infinite one-dimensional loop-like chain structure and Haip ligand in 1 is of zwitterionic form. Magnetic measurement results show the dominated ferromagnetic interactions among Fe11 atoms.

Synthesis and Characterization of a Thiolate-bridged Diiron Complex with Two Monocoordinated Azido Ligands： [Cp＊Fe（μ-SMe）N3]2 （Cp＊ =η^5-C5Me5）

A new thiolate-bridged diiron complex with two mono-coordinated azido ligands, [Cp＊Fe（kt-SMe）N3]2 （Cp^＊ = η^5-C5Me5）, was synthesized from [Cp＊Fe（η-SMe）MeCNMPF6]2 and NaN3 in a bi-solvent system of acetone and methanol. X-ray crystal structural analysis shows that the compound belongs to the orthorhombic Fdd2 space group, with a = 14.3771（15）, b = 71.424（8）, c = 9.7010（10）A, V = 9961.7（18） A3, C22H36Fe2N6S2, Mr = 560.39, Dc = 1.495 g/cm^3, F（000） = 4704,μ（MoKa） = 1.355 mm-I and Z = 16. The compound consists ofa di（u-thiolate）diiron unit {Cp＊Fe（p-SMe）}2, in which each iron is coordinated by a terminal azido ligand. Magnetic characterizations show spin canting behavior for the title compound.

Synthesis and Structural Characterization of a Cyano-bridged Dinuclear Neodymium(III)-iron(III) Complex [Nd(DMSO)_5(H_2O)_2](μ-CN)[Fe(CN)_5]

A new neodymiumIII-ironIII complex [Nd(DMSO)5(H2O)2](μ-CN)[Fe(CN)5] (DMSO = dimethyl sulfoxide) has been synthesized by the grinding reaction method. The crystal belongs to monoclinic, space group P21/m with a = 8.859(4), b = 13.684(5), c = 12.290(4) ?, ?= 91.85(2)o, C16H34FeN6NdO7S5, Mr= 782.88, V = 1489(1) ?3, Z = 2, Dc = 1.746 g/cm3, S = 0.906, μ(MoKa) = 2.606 mm-1, F(000) = 788, R = 0.0646 and wR = 0.1654. The slightly distorted square-antiprism eightfold-coordinated Nd(III) and approximately oriented octahedrally sixfold- coordinated Fe(III) are linked by a cyano-bridge group to construct a dinuclear compound. The [Nd(DMSO)5(H2O)2](μ-CN)[Fe(CN)5] species are held together via hydrogen bonds to form a three-dimensional framework.

Synthesis, Structure and Characterization of a Novel Asymmetrical Half-sandwich Binuclear Iron Carborane Complex [η5-C5H3(t-Bu)2]2Fe2(CO)3Se2C2B10H10

Halfsandwich iron dicarbonyl complex [η 5-C5H3（t-Bu）2]Fe（CO）2Cl（1） reacts with 1, 2-dilithium diseleno carborane Li2Se2C2B 10H 10（2） to give a binuclear iron carborane complex [η 5-C5H3（t-Bu）2]2Fe2（CO）3·Se2C2B 10H 10（3）. The X-ray diffraction analysis of complex 3 reveals that one of the iron atoms is chiral.

PROSPECTS AND CRUCIAL PROBLEMS IN OLIGOMERIZATION AND POLYMERIZATION WITH IRON AND COBALT COMPLEX CATALYSTS

The discovery of highly active 2,6-bis（imino）pyridyl iron and cobalt complexes provided a milestone of latetransition metal catalysts for ethylene oligomerization and polymerization with being currently investigated for the scale-up process. The crucial problems are remaining in the catalytic systems： the catalytic systems targeting ethylene polymerization produce more oligomers at elevated reaction temperatures, however, there is a recognizable amount of high-molecularweight polyethylene remained in the modified catalytic system for the oligomerization process. Beyond the modification of bis（imino）pyridyl metal complexes, several alternative proeatalysts＇ models have been developed in our group. This review highlighted the achievements in exploring new iron and cobalt complexes with tridentate NNN ligands as procatalysts for ethylene oligomerization and polymerization.

Catalytic Effect of Cobalt and Iron Complexes Incorporating Bis(2-aldiminoethyl)amine Ligands on Ethylene Oligomerization

Complexes [MCl 2{CH 3N(CH 2CH 2N[CDS1]CR 1R 2) 2}]((3, M=Co, R 1=H, R 2=Ph ; 4, M=Fe, R 1=H, \{R 2=Ph\}; 5, M=Co, R 1=R 2=Ph) were prepared and characterized by IR spectra and elemental analysis. The combination of each of complexes 3-5 with ethylaluminoxane(EAO), respectively, was found to be moderately active for ethylene oligomerization to low carbon olefins. The activity of 113 kg oligomers·mol -1 Co·h -1 for complex 3(100 mol of EAO, 180 ℃ and 1 8 MPa ethylene) was observed with a selectivity of 93% to C 4-10 olefins, of which 96% were linear C4 10 olefins. The catalytic properties of complexes 3-5 were compared with those of analogous P,P coordinated complexes [MCl 2{CH 3N(CH 2CH 2PPh 2) 2}](1, M=Co; 2, \{M=\}Fe).

Polymerization of Norbornene via an Iron-Based Complex/MAO Catalytic System

Polynorbornenes were synthesized in the presence of an iron based catalyst, 2,6-bis[1-(2,6-diisopropyl-phenylimino)ethyl]pyridine iron(Ⅱ) dichloride. The FTIR, 1H NMR and 13C NMR analysis results revealed that the structure of the obtained polynorbornenes consisted of vinyl addition polymer substructures without any ring-opening structures. The polymers were amorphous with a short-range order, displayed in the WAXD(wide angle X-ray diffraction) diagrams. The glass transition temperatures ranged from 200 to 400 ℃. The effects of the polymerization reaction conditions, such as Al/Fe molar ratio and toluene/CH_2Cl_2 volume ratio, on the activity, intrinsic viscosity and T_g were also studied.

Structure and Magnetic Property of an Oxygenand Carboxamide-bridged One-dimensional Iron(Ⅲ) Complex [Fe_2(μ-O)(bpb)_2]_n

The structure of the title complex [Fe2（μ-O）（bpb）2]n （bpb 2=1,2-bis（pyridine-2carboxamido） benzenate） has been characterized by single-crystal X-ray diffraction analysis.The complex （C36 H24 Fe2N8O5,Mr=760.33） crystallizes in the monoclinic space group P2 1/c with a=8.4615（17）,b=33.704（7）,c=11.173（2）,β=91.12（3）o,V=3185.7（11）3,Z=4,D c=1.585 g/cm 3,μ（MoK）=0.970 mm-1,F（000）=1552,R int=0.0381,the final R=0.0454 and wR=0.1114.The magnetic susceptibilities of the complex have been examined in the temperature range of 2-300 K.The magnetic data were fitted to give the parameters of J d=-77.7（9） and J c=-11.5（6） cm-1.

POLYMERIZATION OF ETHYLENE WITH UNSYMMETRIC 2,6-BIS(IMINO)PYRIDINE IRON(Ⅱ)COMPLEX

An unsymmetric 2,6-bis(imino)pyridine iron(II) complex 1' was synthesized. The relationship between catalyststructure and its activity in ethylene polymerization is discussed. The kinetic behavior of ethylene polymerization and theeffects of polymerization conditions such as temperature, aluminum/iron molar ratio on the activity of catalyst and thecharacteristics of polyethylene were reported. The unsymmetric catalyst 1' has a good catalytic performance of 3.47×10~6 gPE·mol^(-1)·Fe·h^(-1) at 40℃ with aluminum/iron molar ratio = 2500. A dependence of catalyst activity on themethylaluminoxane (MAO) concentration and reaction temperature was found. The molecular weight (MW) of polyethylenewith broad dispersity is about 10~4-10~5 g/mol. The melting temperature and branching of polyethylenes vary with changingreaction temperature and aluminum/iron molar ratio.

Efficacy and Compliance of Oral Iron Poly-Maltose Complex versus Oral Ferrous Sulfate in the Treatment of Iron Deficiency Anemia in Pregnant Women

Objective: To compare the efficacy and compliance of the conventional therapy of iron deficiency anemia (ferrous sulfate) with the new forms of therapy chewable iron tablets: (iron polymaltose complex) in the treatment of iron deficiency anemia in pregnant women. Methods: This Randomized Control Trial study included 290 pregnant women with iron deficiency anemia, and they were randomly allocated to a control group who received ferrous sulfate capsules for two months and study group who received iron polymaltose complex chewable tablets for two months. Complete Blood Picture (hemoglobin level and hematocrit level) and Serum ferritin level were done after four and eight weeks to determine the efficacy. In addition, any complains or side effects had been reported to assess the tolerability of the drugs. Two-factor repeated-measures analysis of variance (ANOVA) was used to compare the change in hemoglobin and serum ferritin levels in both groups. Results: There was no statistical significant difference between the two research groups as regards baseline hemoglobin, and at week 4 from onset of treatment (p values = 0.990, 0.112, consecutively). However, there was statistical significant difference on week 8 of continuous drug intake in both groups in which the iron poly maltose complex research group had significantly higher hemoglobin levels (p value = 0.006). Conclusion: The results of the study showed oral iron polymaltose complex increases Hemoglobin and serum ferritin levels more than oral ferrous sulfate and produces less adverse effects than ferrous sulfate.