A panel set for epitope analysis of myeloperoxidase (MPO)-specific antineutrophil cytoplasmic antibody MPO-ANCA using recombinant hexamer histidine-tagged MPO deletion mutants

The nu2/nu4 dyad of arsine, AsH3, has been investigated between 875 and 1100 cm-1 by laser sideband spectroscopy. In total 189 transitions have been observed with sub-Doppler resolution ( approximately 300 kHz) and measured to an absolute accuracy of about 100 kHz. These data may be useful to serve as a secondary frequency standard. Our observations include four perturbation-allowed transitions with Delta(k - l) = 3. Saturation spectra of dipole forbidden transitions had not been previously reported for arsine. Quadrupole hyperfine structure, as well as vibration-rotation splitting of |k - l| = 3N levels in both fundamentals, has been analyzed. Combining our results with MW and RF data (239 frequencies) reported in the literature, a total of 882 transition frequencies were available to fit 15 ground state parameters and 48 excited state parameters of the nu2/nu4 dyad. The standard deviation of the fit is 245 kHz. Copyright 1998 Academic Press. Copyright 1998Academic Press     

Analysis of the reactivity effect of spatial noise in the framework of two-group diffusion theory

The reactivity effect of spatial random dispersal of core materials was analyzed in the framework of one-group diffusion theory by the time-eigenvalue method, and in the framework of two-group diffusion theory by both the time- and the reactivity-eigenvalue methods. The analysis based on one-group diffusion theory leads to that spatial random perturbations in the macroscopic cross sections and/or the diffusion coefficient cause the positive reactivity effects under the assumption of zero ensemble-averages of these perturbations. However, the analysis based on two-group diffusion theory shows that the algebraic sign of the reactivity depends upon the reactor types and the buckling. A specific example in which spatial noise causes the negative reactivity was also shown.     

UPGRADING OF COAL-DERIVFD LIQUIDS. 2. CHARACTERIZATION OF UPGRADED LIQUIDS BY GAS CHROMATOGRAPHIC DISTILLATION

ABSTRACT

Gas chromatographic distillation (GCD) based ors ASTM 02887 has been applied to characterizing the boiling range distribution of upgraded coal-derived liquids. It has beer demonstrated that the GCD method based on ASTM D2887 can be used as a substitute for ASTM D2892. A variety of coal-derived liquids can be characterized and the procedure may be effective for estimating the degree of conversion as a means of screening for hydroconversion catalysts.     

UPGRADING OF COAL-DERIVED LIQUIDS. 1. CATALYTIC ACTIVITIES OF ZEOLITE CATALYSTS AND COMMERCIAL HDS CATALYSTS

The applicability of various zeolite catalysts and commercial HDS catalysts to the secondary hydrotreatment of coal-derived liquids was examined in relation to the chemical structure of upgraded liquids. The catalytic activities of zeolite catalysts for HI conversion is lower than are the activities of Ni-Mo, Ni-Co-Mo, Co-Mo and Ni-W catalysts. However, as regards hydrogenation and the removal of nitrogen, zeolite catalysts such as natural clinoptilolite and mordenite have almost the same activity as do Co-Mo and Ni-W catalysts. As to the removal of oxygen, it was proved that zeolite catalysts had a functionality to remove oxygen as COx gas, and HDS catalysts had a high activity for hydrodeoxygenation.     

UPGRADING OF COAL-DERIVFD LIQUIDS. 2. CHARACTERIZATION OF UPGRADED LIQUIDS BY GAS CHROMATOGRAPHIC DISTILLATION

Gas chromatographic distillation (GCD) based ors ASTM 02887 has been applied to characterizing the boiling range distribution of upgraded coal-derived liquids. It has beer demonstrated that the GCD method based on ASTM D2887 can be used as a substitute for ASTM D2892. A variety of coal-derived liquids can be characterized and the procedure may be effective for estimating the degree of conversion as a means of screening for hydroconversion catalysts.     

Novel Neodymium-Based Ternary Catalyst, Nd(Oi-Pr)3/[HNMe2Ph]+[B(C6F5)4]-/i-Bu3Al, for Isoprene Polymerization

Summary Polymerization of isoprene was investigated by using a novel ternary catalyst system composed of neodymium(III) isopropoxide (Nd(OiPr)₃), dimethylphenylammonium tetrakis(pentafluorophenyl)borate ([HNMe₂Ph]⁺[B(C₆F₅)₄]^-; borate), and triisobutylaluminum (i-Bu₃Al). The mole ratios of borate and aluminum compounds to Nd catalyst significantly affected the polymerization behavior. Both yield and cis-1,4 content of polyisoprene decreased in the case of [borate]/[Nd] < 1.0, while at [borate]/[Nd] > 1.0 the formation of multiple active species resulted in the polymer showing bimodal peaks in GPC. When the [Al]/[Nd] ratio was lower than 30, the polymer yield sharply decreased, whereas the cis-1,4 content became relatively low with use of a large excess of Al ([Al]/[Nd] > 50). Thus, the optimal catalyst composition was [Nd]/[borate]/[Al] = 1/1/30, which gave in > 97% yield polyisoprene with high molecular weight (M_n2×10⁵) and relatively narrow molecular weight distribution (M_w/M_n2.0) and mainly cis-1,4 structure (90%).     

Liquefaction reaction of coal: 2. Structural correlation between coal and its liquefaction products

The structural correlation between coal and its liquefaction products has been examined using cross-polarization, magic angle spinning (CP/MAS) ¹³C n.m.r. and field ionization mass spectrometry (f.i.m.s.). The CH₂/aromatic carbon ratios of all solid products (asphaltene, preasphaltene and residue) were close to the corrected +CH₂/aromatic carbon ratio for the coal. This suggests that the ring structure of the structural unit of each solid product is essentially similar to that of the parent coal, except for a difference in the degree of polymerization of the structural units. The CH₂/aromatic carbon ratios of aromatic ring-type oil fractions also correlated with the corrected ratio for the coal, although they were larger. The z series distribution obtained from the f.i.m.s. of oil fractions revealed that coal with a higher CH₂/aromatic carbon ratio produced an oil rich in naphthenic structures.     

Coal liquefaction by colloidal iron sulphide catalyst

Taiheiyo coal, which was treated with an aqueous solution of dodecyltrimethylammonium chloride, adsorbed colloidal iron sulphide prepared from FeS0₄ · 7H₂O and Na₂S · 9H₂O in aqueous media. The adsorbed colloidal iron sulphide was much more effective as a catalyst for the liquefaction of the coal itself than the usual powder-type iron sulphide. Thus in differential thermal analysis under hydrogen, the coal with 0.35wt% adsorbed colloidal iron sulphide gave an exothermic peak at 401 °C, which was ≈20 °C lower than when using the powder-type iron sulphide. The coal was smoothly hydrogenated at 450 °C to give a yield of ≈60% liquid products.