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The isothermal reduction of oxide scale on hot-rolled, low-carbon steel strip in 10 pct H2-Ar mixtures in the temperature range of 673 K to 1073 K (400 °C to 800 °C) was investigated by using a thermo-gravimetric analyzer (TGA). During heating under an argon atmosphere, magnetite/iron eutectoid and proeutectoid magnetite in the oxide scale successively transformed into wustite at a temperature above 843 K (570 °C). The kinetic plot of the isothermal reduction assumes a sigmoid shape, including induction, acceleration, and finally the decaying stage. Fitting the kinetic curve to mathematical models, the reaction at 1073 K (800 °C) and 773 K (500 °C) were determined to be controlled by phase-boundary-controlled reaction and three-dimensional growth of nuclei, respectively. The reduction product varies with temperature and itself affects the kinetics. Porous and dense iron were, respectively, obtained below and above 873 K (600 °C). A “rate-minimum” was observed at 973 K (700 °C) due to the formation of dense iron that blocks the gas diffusion. Due to the structural transformation of oxide scale during heating, the reactant depends on the heating process. However, compared with the oxide scale structure, the temperature is more important in determining the reduction kinetics at temperatures above 973 K (700 °C).

Titanium has been added in the Al coatings on sintered NdFeB magnets by ion-beam-assisted magnetron sputtering to improve the mechanical properties of coatings without corrosion resistance deterioration. The effect of Ti addition on structure, mechanical and electrochemical properties of Al coatings has been investigated, complemented by x-ray diffraction and transmission electron microscopy. The results show that the ion-beam-assisted magnetron co-sputtering of Al and Ti obtains a single-phase polycrystalline structure of Al–Ti solid solution. With the increasing Ti content, the coating structure becomes denser and the grain size is reduced. Both the mechanical and wear properties of the coatings are improved with the addition of Ti where the hardness of the Al–Ti coating increases with the increasing amount of Ti. Polarization and EIS testing results show that the titanium-doped coatings have an enhanced corrosion resistance by comparison with pure Al coatings when Ti content is lower than 4.3 at.%.

Al-5.8Mg-0.4Mn-0.25Sc-0.1Zr (mass fraction, %) alloys were prepared by water chilling copper mould ingot metallurgy processing which was protected by active flux. The recrystallization temperature and nucleation mechanism of the alloy were studied by means of hardness tests, observations of optical microscopy and transmission electron microscopy. The results show that the anti-crystallization ability can be significantly improved by adding minor Sc and Zr into Al-Mg-Mn alloy. This can be proved by a much higher recrystalliztion temperature (450 °C) than Al-Mg-Mn alloy without Sc and Zr (150 °C). The main reason of the great increase of recrystallization temperature can be attributed to the strong pinning effect of highly disperseded Al3(Sc,Zr) particles on dislocations and sub-grain boundaries. The recrystallizing process reveals itself the nucleation mechanism of the alloy involving not only the sub-grain coalescence but also the sub-grain growth.

Two new copper(II) complexes, [Cu(p-FBA)2(2,2′-bpy)]·(H2O) (1) and [Cu(p-FBA)(2,2′-bpy)2]·(p-FBA)2 (2) {p-FBA = p-fluorobenzoic acid, 2,2′-bpy = 2,2′-bipyridine} have been obtained from an identical starting mixture using temperature as the only independent variable and characterized by X-ray single crystal diffraction as well as with infrared spectroscopy, elemental analysis, and thermogravimetric analysis. The results reveal that 1 has 1D infinite chain structure formed by O–H···O hydrogen bonds, while 2 features a 0D structure. Additionally, there exist C–H···O hydrogen bonds and π–π stacking interactions in 1, forming 2D supramolecular structure. Furthermore, density functional theory (DFT) calculations of the structures, stabilities, orbital energies, composition characteristics of some frontier molecular orbitals and Mulliken charge distributions of the [Cu(p-FBA)2(2,2′-bpy)] of 1 and [Cu(p-FBA)(2,2′-bpy)2]+ cation of 2 were performed by means of Gaussian 03W package and taking B3LYP/lanl2dz basis set.

Self-assembly reactions of copper (II) ions, dicarboxylate (adipate or terephthalate) and terminal ligands (4,4′-bipyridine or phenanthroline) yielded three hydroxy-bridged Cu(II) cluster complexes: [Cu(phen)(OH)(H2O)]2·(C8H4O4)·8H2O (1), [Cu4(bpy)4(OH)4(H2O)2]·(C8H4O4)2·6H2O (2) and [Cu6(bpy)6(OH)6(H2O)2]·(C6H8O4)3·23H2O (3) (phen = phenanthroline, bpy = 2,2′-bipyridine, C8H6O4 = terephthalic acid, C6H10O4 = adipic acid). Single crystal X-ray diffraction analyses reveal that complex 1 is a discrete dinuclear Cu2O2 motif, 2 presents a discrete chairlike tetranuclear copper(II) Cu4O4 core formed by two Cu2O2 units, and 3 assumes a discrete hexameric copper(II) Cu6O6 cluster consisting of three Cu2O2 units. The polynuclear structures are generated from the Cu(II) ions linked by the µ2- and/or µ3-OH groups. In 1−3, all Cu(II) ions show square pyramidal coordination geometry, and the dicarboxylate ions act as counteranions to keep the whole structure neutral. Thermogravimetric analyses (TGA) and magnetic prop...

Reversible addition–fragmentation chain transfer (RAFT) polymerization was used to prepare polymer brushes grafted onto silicon wafer surface. Novel RAFT agent was prepared and immobilized on the silicon wafer surface. RAFT polymerizations were then conducted from the silicon surface to graft polymer brush to the silicon. Analysis of the polymer brush layers was conducted using ellipsometry, XPS, AFM and contact angle measurements, respectively.

In the polymeric title compound, [Cd(C7H4O6S)(C11H6N2O)(H2O)2]n, the Cd2+atom is seven-coordinated by two water O atoms, by three O atoms from two 2-hydroxy-5-sulfonatobenzoate (Hssal2−) ligands and by two N atoms from a 4,5-diazafluoren-9-one (Dafo) ligand in a distorted pentagonal–bipyramidal geometry. The Cd2+atoms are monodentately coordinated by the sulfonate group of one Hssal2−ligand and bidentately coordinated by the carboxylate group of another Hssal2−ligand, generating zigzag chains running parallel to [010]. The chains are linked by O—H...O hydrogen bonds into a three-dimensional architecture.

In this paper, we present the nanofabrication of a potentially coupled waveguide-surface plasmon resonance biosensor (CWSPRBs) by nanoimprint lithography. Subwavelength metallic gratings (SWMGs) with the pitches of 300 and 500nm were fabricated by direct imprinting on PMMA layer which subsequently covered with a layer of Au. The key issue in this device is the coupling of surface plasmon with waveguide modes, which has been carefully investigated by measuring the coupling induced enhancement of light transmission. Both our measurement and simulation results indicate that the resonant coupling does exist for both 300 and 500nm pitched gratings. This proves that the developed nanoimprint lithography is applicable for the CWSPRBs sensors which has significant advantages over traditional ones with a prism.

C12H21Mo12N6O40P, monoclinic, P121/n1 (no. 14), a = 12.0565(5) A, b = 15.8669(7) A, c = 22.996(1) A, 0 = 98.037(1)°, V = 4355.8 A, Z = 4, Rgt(F) = 0.029, wRref(F ) = 0.070, T = 293 K. Source of material To a 20ml acetonitrile solution ofH3PMo12O40 · 24H2O (1 g)was added 0.1 g methylimidazole in 20 ml acetonitrile with stirring at room temperature. A large quantity of orange yellow precipitate was formed immediately and was filtered off. After the filtrate was kept standing for 3 days, the orange yellow crystals were collected. Discussion The title compound consists of a PMo12O40 anion and three protonated 2-methylimidazole cations. The Keggin PMo12O40 anion is based on a central PO4 tetrahedron surrounded by twelve MoO6 octahedra arranged in four groups of three edge-shared octahedra Mo3O13. These Mo3O13 triplets are linked by the shared corners to each other and the central PO4 tetrahedron. Each of all the Mo atoms in the distorted octahedral environment connects with one terminal oxygen atom (Ot), four doubly bridging oxygen atoms (Ob), one triply bridging oxygen atom (Oc), forming a distortedMoO6 octahedron. TheMo-Modistances are in the range 3.395(1) 3.716(1) A, mean 3.558 A, and the bond angles of O−Mo−O range from 71.6(1) A to 171.8(1) A. The Mo—Ot distances are in the range of 1.662(3) A to 1.680(3) A, average 1.669 A. The Mo—Ob distances range from 1.846(3) A to 1.980(3) A, average 1.914 A. The Mo—Oc distances are in the range 2.419(2) 2.453(3) A, average 2.434 A. The alternating short and longMo—Ob—Mobonds,which result from small displacements of Mo atoms from the mirror planes of the Mo3 triangle in the Keggin anions [1]. The 2-methylimidazolium cations exhibit normal C—CandC—Nbond distances [2,3], which form intermolecular N−H···Ohydrogen bonding to oxygen atoms of the polyanions (d(N···O) = 2.967 3.110A). By virtue of these hydrogen bonds, the adjacent units are connected, stabilizing the whole structure. 432 Z. Kristallogr. NCS 223 (2008) 432-434 / DOI 10.1524/ncrs.2008.0189 © by Oldenbourg Wissenschaftsverlag, Munchen Crystal: orange yellow column, size 0.134 × 0.187 × 0.288 mm Wavelength: Mo K2 radiation (0.71073 A) ': 34.88 cm−1 Diffractometer, scan mode: Bruker SMART APEXII CCD, +/3 2#max: 53.8° N(hkl)measured, N(hkl)unique: 25171, 9449 Criterion for Iobs, N(hkl)gt: Iobs > 2 "(Iobs), 7114 N(param)refined: 641 Programs: SHELX-90 [4], SHELXS-97 [5], SHELXL-97 [6], SHELXTL [7] Table 1. Data collection and handling. H(1A) 4e 0.9850 1.0102 0.0521 0.087 H(1B) 4e 0.9333 1.0906 0.0774 0.087 H(1C) 4e 0.8554 1.0255 0.0402 0.087 H(3A) 4e 0.9571 0.8467 0.2168 0.058 H(4A) 4e 0.7962 0.9347 0.2306 0.048 H(5A) 4e 0.7676 0.6219 0.0717 0.094 H(5B) 4e 0.8958 0.6231 0.0663 0.094 H(5C) 4e 0.8554 0.6425 0.1268 0.094 H(7A) 4e 0.7694 0.3349 0.1119 0.087 H(8A) 4e 0.9601 0.3552 0.1578 0.090 H(9A) 4e 0.2983 0.8388 0.4254 0.119 H(9B) 4e 0.3426 0.7563 0.3991 0.119 H(9C) 4e 0.2902 0.7524 0.4577 0.119 H(11A) 4e −0.0574 0.8067 0.3209 0.071 H(12A) 4e −0.0194 0.6589 0.3255 0.094 H(1D) 4e 0.7794 1.0346 0.1464 0.044 H(2A) 4e 1.0238 0.9002 0.1295 0.050 H(3B) 4e 0.7045 0.4730 0.0778 0.081 H(4B) 4e 0.9984 0.5022 0.1505 0.084 H(5D) 4e 0.1705 0.6435 0.3814 0.094 H(6A) 4e 0.1121 0.8747 0.3733 0.062 Table 2. Atomic coordinates and displacement parameters (in A). Atom Site x y z Uiso

Dy-doped α-SiAlON ceramics with a combined property of optical translucence and wear resistance is reported in the present presentation. A considerable test was made on the tribological behavior of the Dy-α-SiAlON to find out the effects of temperature and sliding conditions on the wear properties. It was shown that the friction coefficient was the lowest (0.26) at 100°C under an applied load of 5N. Accordingly, the wear rate was the lowest at 100°C for the same Dy-α-SiAlON sample. Obviously Dy-SiAlON shows an excellent wear resistance under a suitable sliding condition under a load of 5N and 100°C condition. This appears, therefore, attractive and important for Dy-SiAlON ceramics to be used as a type of special wear resistant materials, with an optical translucence.

A thin layer of diamond-cluster/iron composite was formed near the surface of carbon steels/cast iron after a repeated irradiation by a short-pulsed ArF excimer laser. The presence of diamond is characterized by SEM and Raman spectroscopy. The formation mechanism is discussed in terms of sp 3 -carbon aggregation in the locally melted carbon-containing iron. The catalytic effect of iron on the formation of diamond is further enhanced by the presence of high energy (∼6.4 eV) photons provided by the ArF excimer laser, which acts as both a pyrolytic source for local melting and a photolytic bond-breaker.

The title lanthanide–bdc complex, {[Lu2(C8H4O4)3(H2O)8]·2H2O}n (bdc is benzene-1,4-dicarboxyl­ate), was synthesized under hydro­thermal conditions. In this complex, the LuIII centers are eight-coordinated by four O atoms from three benzene-1,4-dicarboxyl­ate ligands and four from water mol­ecules. LuIII ions are bridged by benzene-1,4-dicarboxyl­ate anions in two modes, forming polymeric chains. These chains are further assembled into a three-dimensional supramol­ecular network by O—H⋯O hydrogen-bonding inter­actions.

In the title coordination polymer, [Dy2(C6H8O4)(C2O4)2(H2O)2]n, the asymmetric unit consists of one Dy3+cation, one half of an adipate anion, two halves of oxalate anions and one coordinating water molecule. The adipate and oxalate ions are located on centres of inversion. The Dy3+cation has a distorted tricapped trigonal–prismatic geometry and is coordinated by nine O atoms, four belonging to three adipate anions, four to two oxalate anions and one from an aqua ligand. The cations are bridged by adipate ligands, generating a two-dimensional network parallel to (010). This network is further extended into three dimensions by coordination of the rigid oxalate ligands and is further consolidated by O—H...O hydrogen bonds. A part of the adipate anion is disordered over two positions in a 0.75:0.25 ratio.

In the title compound, [Lu(2)(C(8)H(4)O(4))(2)(C(2)O(4))(H(2)O)(2)](n), the Lu(3+) cations are each coordinated by eight O atoms of four terephthalate anions, one oxalate anion and one aqua ligand to complete a distorted square-anti-prismatic geometry. They are bridged by the terephthalate ligands, generating a three-dimensional framework, which is further stabilized by the oxalate ligands. The terephthalate ions and oxalate ions are all located on centers of inversion.

C18H15N3O, triclinic, P1̅ (no. 2), a = 7.624(2) Å, b = 8.626(2) Å, c = 11.086(2) Å, α = 77.68(3)°, β = 86.66(3)°, ϒ = 86.49(3)°, V = 710.2 Å3, Z = 2, Rgt(F) = 0.088, wRref(F2) = 0.156, T = 293 K.

The title compound, {[Gd2(C12O12)(H2O)10]·4H2O} n , consists of an extended network of Gd ions coordinated by the mellitate anions and water molecules. In this complex, each Gd atom involves a dodecahedral coordination environment comprising five water molecules and three O atoms from two separate mellitate anions. The center of mass of the hexaanion [C6(COO)6]6− coincides with a crystallographic inversion center.

The title compound, [Nd2(C4H4O4)(C8H4O4)2]n, was synthesized by hydro­thermal synthesis. The Nd atom is coordinated by four O atoms from four 1,4-benzene­dicarboxyl­ate ligands and four O atoms from three succinate anions, in a distorted square-anti­prismatic coordination geometry. The anti­prisms are bridged by the 1,4-benzene­dicarboxyl­ate and succinate ligands, forming a three-dimensional network. The succinate ion is located on a centre of inversion.

A new three-dimensional coordination polymer, [Dy2(C4H4O4)(C8H4O4)2]n, has been synthesized under hydro­thermal conditions. The coordination of the Dy atoms is distorted square anti­prismatic. The anti­prisms are bridged by the 1,4-benzene­dicarboxyl­ate and succinate ligands, forming a three-dimensional network. The succinate ion is located on an inversion center.

A new three-dimensional coordination polymer with the formula [Gd2(C8H4O4)2(C4H4O4)]n has been synthesized by hydro­thermal synthesis. The coordination polyhedron around each Gd atom is a distorted square antiprism; the antiprisms are bridged into a three-dimensional network by the 1,4-benzene­dicarboxyl­ate and succinate ligands. The succinate ion is located on a centre of inversion.

The title compound, [La(C6H4NO2)3(C12H8N2)2(H2O)2]·3H2O, consists of a mononuclear complex and three non-coordinated water mol­ecules. The La atom is coordinated by five O atoms of three nicotinate groups and two coordinated water mol­ecules, and four N atoms of two bidentate phenanthroline mol­ecules, in a tricapped trigonal–prismatic coordination geometry. The complex mol­ecule and water mol­ecules are linked into layers through O—H⋯O and O—H⋯N hydrogen bonds.

In the centrosymmetric title compound, [Gd(2)(C(6)H(8)O(4))(C(2)O(4))(2)(H(2)O)(2)](n), the Gd(3+) cations are each coordinated by nine O atoms, three from adipate anions, two from oxalate anions and one from an aqua ligand, completing a distorted tricapped trigonal-prismatic geometry. These tricapped trigonal prisms are bridged by the adipate ligands, generating layers lying parallel to (010). The coordination polymer layers are linked into a three-dimensional framework by the rigid oxalate ligands. The adipate and oxalate ions are all located on centers of inversion. A part of the adipate anion is disordered over two positions in a 0.75:0.25 ratio.

The crystal structure of the title complex, [Yb(2)(C(8)H(4)O(4))(2)(C(2)O(4))(H(2)O)(2)](n), features an extended three-dimensional framework made up of Yb(3+) ions coordinated by terephthalate ligands, oxalate ligands and water mol-ecules. The Yb(3+) ion has a distorted square-anti-prismatic coordination formed by one aqua ligand, two O atoms from an oxalate ligand and five O atoms belonging to four terephthalate anions. Two symmetry-independent terephthalate anions, as well as the oxalate anion, occupy special positions on inversion centers. The water molecule participates in O-H⋯O hydrogen bonding with both terephthalate anions.

In the title compound, [Y(2)(C(4)H(4)O(4))(2)(C(2)O(4))(H(2)O)(2)](n), the flexible succinate anion assumes a gauche conformation and bridges the eight-coordinated Y atoms, generating two-dimensional layers parallel to (010). The coordination polymer layers are linked into a three-dimensional framework by the rigid oxalate ligands. The oxalate ions are located on a center of inversion. Inter-molecular O-H⋯O hydrogen bonds help to stabilize the crystal structure.

The title complex, [Sm(2)(C(3)H(5)O(2))(6)(C(12)H(8)N(2))(2)], is a dinuclear centrosymmetric mol-ecule, in which two crystallographically equivalent Sm atoms, separated by 3.9502 (2) Å, are bridged by four propanoate anions. Each Sm atom is coordinated by two N atoms from one chelating phenanthroline ligand and seven carboxylate O atoms from five propanoate anions, to form a distorted tricapped trigonal prism.