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A fundamental study on the precipitation behavior of carbides was carried out. Thermo-calc software, scanning electron microscopy, electron probe microanalysis, transmission electron microscopy, X-ray diffractometry and high-temperature confocal laser scanning microscopy were used to study the precipitation and transformation behaviors of carbides. Carbide precipitation was of a specific order. Primary carbides (M7C3) tended to be generated from liquid steel when the solid fraction reached 84 mol.%. Secondary carbides (M7C3) precipitated from austenite and can hardly transformed into M23C6 carbides with decreasing temperature in air. Primary carbides hardly changed once they were generated, whereas secondary carbides were sensitive to heat treatment and thermal deformation. Carbide precipitation had a certain effect on steel-matrix phase transitions. The segregation ability of carbon in liquid steel was 4.6 times greater that of chromium. A new method for controlling primary carbides is proposed.

Effects of temperature and slag composition on dephosphorization in a 120 ton top-bottom combined blown converter steelmaking process by double slag method were studied. The slag properties were determined by scanning electron microscope- energy dispersive spectrometry (SEM-EDS), X-ray diffraction (XRD). The results show that the transition oxidation temperature between dephosphorization and decarbonization Tf is not the favorable temperature for the first deslagging. The optimum first deslagging temperature is confirmed to be approximately 1,673 K which is about 70 K higher than Tf. High melting temperatures phases (such as 3CaO·SiO2) in the slag with high basicity and MgO content are unfavorable to the dephosphorization. The optimum process condition for dephosphorization at the first deslagging in present work is approximately 1,673 K in temperature, 2.0 in slag basicity, 6 and 17 mass% in MgO and T.Fe content, 6 mass% ≤ MnO content.

C38H42N2, monoclinic, P21/c (no. 14), a = 5.1381(4) Å, b = 14.238(1) Å, c = 21.372(2) Å, β = 92.359(4)°, V = 1562.2 Å3, Z = 2, Rgt(F) = 0.0863, wRref(F2) = 0.2868, T = 130(2) K.

C 15 H 5 Br 4 N 3 O 3 , tetragonal, I4 1 md (no. 109), a = 29.303(1) A, c = 4.0462(5) A, V= 3474.3 A 3 , Z = 8, R gt (F) = 0.057, wR ref (F 2 ) = 0.186, T = 293 K.

C4H2S5, orthorhombic, Prima (No. 62), a = 13.015(1) A, b = 9.193(1) Â, c = 6.151(1) Â, y = 735.9 A, Z = 4, Rst(F) = 0.040, wRref(F) = 0.118, Τ = 293 Κ. Source of material The title compound was synthesized according to the literature [1]. The flash amaranth block-shaped [N(butyl)4]2[Zn(dmit)2] (dmit = l,3-dithiol-2-thione-4,5-dithiolate, C3S5) (A) was dissolved in acetone contained by a three-neck flask. Under nitrogen atmosphere and at 313 K, the freshly distilled CHbBra (B) in the molar ratio of two to one (B/A) was added with stirring to the flask. The mixture was filtered through celite after 2 days and concentrated to give a dark brown residue. The title compound was isolated from the filtrate as one of products using column chromatography on silica gel. Evaporation of a solution in petroleum ether afforded single crystals suitable for X-ray diffraction (mp 424.70 K). Composition: calculated for C4H2S5 C, 22.84%; H, 0.96%; found C, 22.90%; H, 0.95%. Spectroscopic data are included into the CIF file. Discussion The ring defined by C1-S1-C2-C2A-S1A atoms is planar. Torsion angles of C1-S1-C2-C2A and C2-S1-C1-S1A are 11.1(3)° and -18.1(5)°. The thione ring defined by C2-S2-C3-S3-S2AC2A-C2A atoms is also planar, of which planarity is superior to that of the first ring. Torsion angles of C2-S2-C3-S2A, C2-S2-C3-S3 and C3-S2-C2-C2A are -0.6(2)°, -179.7(2)° and 0.4(1)°, respectively. The dihedral angle between these two ring planes is 4.6° implying that they are almost co-planar except two hydrogen atoms on the methylene deviated greatly from the least-square plane of all non-hydrogen atoms. Torsion angles of C3-S2-C2-S1 and C1-S1-C2-S2 are -178.5(2)° and -170.0(3)°. The covalent bond lengths and angles in 4,5-methylenedithioI,3-dithiol-2-thione are found to be consistent with those of similar structures [2-3], Relevant bond lengths: d(S2—C3) = 1.726(2) Â, d(S2—C2) = 1.734(2) A, ?(S3—C3) = 1.655(3) Â, d(Sl—C2) = 1.742(2) Â,r f (Sl—Cl)= 1.788(3) Â,d(C2—C2A)= 1.344(5) A, d(C3—S2A) = 1.726(2) Â, d(Cl—SIA) = 1.788(3) Â; bond angles: Z C 3 S 2 C 2 = 96.2(1)°, Z C 2 S 1 C 1 = 93.1(2)°, ZC2A-C2-S2 = 116.66(8)°, ZC2A-C2-S1 = 118.27(8)°, Z S 2 C 2 S 1 = 125.1(1)° , Z S 3 C 3 S 2 = 122.85(9)° , Z S 3 C 3 S 2 A = 122.85(9)°, Z S 2 C 3 S 2 A = 114.3(2)°, ZS1A-C1-S1 = 113.7(2)°. Intermolecular S ' S short contacts (d(S3 ' -Sl ) = 3.599(1) Â, d(S3'-S2) = 3.4171(9) Â) are observed between the neighborhood molecules, which make an angle of 83.4°. These intermolecular interactions might be key factors in —-— --J J. -0. Table 1. Data collection and handling. Crystal: brown yellow plate, size 0.02 χ 0.56 χ 0.6 mm Wavelength: Mo Ka radiation (0.71073 Â) μ· 14.72 cm" 1 Diffractometer, scan mode: Bruker P4, ω/2θ 20max: 58° N(hkl)measured, N(hkl)unique: 1462, 1042 Criterion for /0bs, N(hkl)gC. /obs > 2