Low-Dose Element-Doped CeCrM/TiO2 (M = La, Cu, Fe, LaCu, LaFe) Catalyst for Low-Temperature NH3-SCR Process: Synergistic Effect of LaCu/LaFe.

A series of CeCrM/TiO2 (M = La, Cu, Fe, LaCu, LaFe) catalysts were prepared via impregnation method and are employed as low-temperature NH3-SCR catalysts. The present study investigates the low-dose element doping on the TiO2-supported catalyst to improve the NH3-SCR performance. And CeCrLaCu/TiO2 exhibited the best catalytic performance (NO conversion approaching 100% at 260-420 °C). The characterization results show that the synergistic effect of LaCu and LaFe on the catalytic performance was more obvious than that of Cu, Fe, and La alone. The doping of LaCu/LaFe decreased the specific surface area of the catalyst but increased the dispersion, surface acidity, and reducibility of the catalyst. Moreover, LaCu/LaFe promoted the formation of valence state distribution and oxygen vacancy content on the surface of the catalyst. There were more Ce3+, Cr6+, Cu+, and oxygen adsorbed on the surface of the CeCrLaCu/TiO2 catalyst. H2-TPR analysis showed that the synergistic effect of LaCu was more likely to promote the reduction of Cr and Cu and increase the reduction degree of metal oxides. However, Fe is easier to coordinate with La, thus improving the redox performance of the catalyst. Compared with CeCrLaFe/TiO2, the ammonia adsorption capacity of CeCrLaCu/TiO2 is better. Therefore, the synergistic effect of LaCu can promote the reaction performance of NH3-SCR better.

Molecular cloning and binding analysis of polymeric immunoglobulin receptor in largemouth bass (Micropterus salmoides).

The polymeric immunoglobulin receptor (pIgR) is an important molecule in the mucosal immunity of teleosts. Previous studies have shown that pIgR can bind and transport polymeric immunoglobulins (pIgs), but few studies have focused on the binding of teleost pIgR to bacteria. In this study, we identified a gene encoding pIgR in largemouth bass (Micropterus salmoides). The pIgR gene contained two Ig-like domains (ILDs), which were homologous to ILD1 and ILD5 of mammalian pIgR. Our results showed that largemouth bass pIgR-ILD could combine with IgM. Moreover, we also found that largemouth bass pIgR-ILD could bind to Aeromonas hydrophila and Micrococcus luteus. Further analysis showed that largemouth bass pIgR-ILD could also combine with lipopolysaccharide (LPS), peptidoglycan (PGN) and various saccharides, and reduced binding to bacteria was observed with LPS and PGN treatment, indicating that largemouth bass pIgR could bind to bacteria to prevent infection and that saccharide binding is an important interaction mechanism between pIgR and bacteria. These results collectively demonstrated that largemouth bass pIgR not only combines with IgM but also binds to bacteria by various saccharides.

Improvement of low-temperature NH3-SCR catalytic performance over nitrogen-doped MO x -Cr2O3-La2O3/TiO2-N (M = Cu, Fe, Ce) catalysts.

A series of MO x -Cr2O3-La2O3/TiO2-N (M = Cu, Fe, Ce) catalysts with nitrogen doping were prepared via the impregnation method. Comparing the low-temperature NH3-SCR activity of the catalysts, CeCrLa/Ti-N (xCeO2-yCr2O3-zLa2O3/TiO2-N) exhibited the best catalytic performance (NO conversion approaching 100% at 220-460 °C). The physico-chemical properties of the catalysts were characterized by XRD, BET, SEM, XPS, H2-TPR, NH3-TPD and in situ DRIFTS. From the XRD and SEM results, N doping affects the crystalline growth of anatase TiO2 and MO x (M = Cu, Fe, Ce, Cr, La) which were well dispersed over the support. Moreover, the doping of N promotes the increase of the Cr6+/Cr ratio and Ce3+/Ce ratio, and the surface chemical adsorption oxygen content, which suggested the improvement of the redox properties of the catalyst. And the surface acid content of the catalyst increased with the doping of N, which is related to CeCrLa/TiO2-N having the best catalytic activity at high temperature. Therefore, the CeCrLa/TiO2-N catalyst exhibited the best NH3-SCR performance and the redox performance of the catalysts is the main factor affecting their activity. Furthermore, in situ DRIFTS analysis indicates that Lewis-acid sites are the main adsorption sites for ammonia onto CeCrLa/TiO2-N and the catalyst mainly follows the L-H mechanism.

Applications of 256-Slice, Spiral Computed Tomography Perfusion Scanning in Limb Salvage After High-Voltage Electrical Injury.

OBJECTIVE: This study aimed to investigate the applications of intelligent 256-slice computed tomography (iCT) perfusion imaging in high-voltage electrical injuries (HVEIs). METHODS: 256-slice iCT was used to perform perfusion scanning for 48 patients with HVEI to detect the perfusion parameters. RESULTS: The blood flow (BF) and peak enhancement intensity (PEI) values of the plane lower than the amputation level of the diseased side (ALD) were smaller than those of the corresponding healthy side (P<0.05); therefore, the differences were statistically significant. The BF value of the plane beyond the ALD was bigger than that of the ALD (t=2.99 and P=0.042); therefore, the difference was statistically significant. The BF, PEI, and blood volume values of the plane below the ALD were smaller than those of the ALD (P<0.05); therefore, the differences were statistically significant. CONCLUSIONS: The technique of 256-slice iCT perfusion imaging could provide richer and more comprehensive imaging data for the clinical treatment of HVEIs, thus exhibiting its benefit in reducing the disability of patients with HVEIs. (Disaster Med Public Health Preparedness. 2018;12:478-485).

[Preparation, characterization and receptor-binding capacity of pig serum transferrin half-molecules containing a single iron-binding site].

N- and C-half molecules containing a single iron-binding site were simultaneously obtained from trypsin digest of iron-saturated pig transferrin. The activities of the pig serum transferrin and of its N- and C-half molecules to bind the human placental membrane transferrin receptor were compared. The results indicate that the receptor-binding site of pig transferrin may be located at the C-half molecule of the transferrin.

Preparation and Biological Activity of [B(1)Ala, B(2)Ala, B(3)Lys]-Insulin.

This paper describes the preparation and biological activity of an insulin analogue in which the B1-3 sequence (Phe-Val-Asn) of insulin is substituted by Ala-Ala-Lys. [B(1)Ala, B(2)Ala, B(3)Lys]-Insulin retains full in vivo activity and receptor binding activity as insulin, but its lipogenesis activity and immunoactivity are 70 % and 0.88 % of those of insulin respectively. The possible contribution of the N-terminus of B-chain of insulin to the structure and function of insulin is discussed.

Protein Engineering of Insulin: [B9 Glutamic Acid] Human Insulin.

B9Ser of insulin B chain was substituted by Glu using site-directed mutagenesis to obtain a fast-acting insulin-[B9Glu] human insulin. The receptor binding capacity and in vivo biological activity of [B9Glu] human insulin are 21% and 40% as those of porcine insulin respectively.

The Receptor Binding and Biological Activity of [B1-Ala, B2-Ala]-insulin.

The receptor binding properties with human placental membrane (HPM) and the in vitro biological activity of an insulin analogue, [B1-Ala, B2-Ala]-insulin were investigated in detail and compared with those of insulin. It was found that the binding of (125)I-[B1-Ala, B2-Ala]-insulin and (125)I-insulin to HPM was time dependent reaching equilibrium after 6min at 37 degrees in the presence of bacitracin with an equilibrium maximum binding of 6.44 fmol/mg protein for [B1-Ala, B2-Ala]-insulin and 3.47 fmol/mg protein for insulin The half time (T1/2) to reach equilibrium was 19 seconds for [B1-Ala, B2-Ala]-insulin and 25 seconds for insulin. [B1-Ala, B2-Ala]-insulin and insulin competed with specific (125)I-[B1-Ala, B2-Ala]-insulin in a dose-dependent manner. From IC(50), the receptor binding activity of [B1-Ala, B2-Ala]-insulin was 139.6% compared with that of insulin. Scatchard analysis revealed that the receptor association constants of [B1-Ala, B2-Ala]-insulin in HPM at 4 degrees were 5.88x10(8)L/mol and 7.63x10(5)L/mol respectively, while those of insulin were 4.83x10(8)L/mol and 3.39x10(5)L/mol respectively. The in vitro activity of [B1-Ala, B2-Ala]-insulin was 130% of that of insulin in terms of lipogenesis in rat adipocytes.