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Here, we elucidate the significant impact of carbon nanotubes (CNTs) on the electrochemical behavior of Mg-based amorphous composite materials that were reinforced with CNTs while using pressure die casting. The addition of 3 vol % CNTs led to an increase in the compressive strength of Mg-based amorphous material from 812 MPa to 1007 MPa, and the fracture strain from 1.91% to 2.67% in the composite. Interestingly, the addition of CNTs significantly contributed to the enhancement of corrosion resistance of Mg-based glass by ~30%. The superior mechanical properties are primarily related to the fact that the addition of CNTs hindered the growth of shear bands (cracks), while the high corrosion resistance is related to inferior wettability and the bridging effect between adherent corrosive oxide film and the matrix that provided enhanced corrosion resistance. [ABSTRACT FROM AUTHOR]

The authors studied the depositional environments, sequence stratigraphy, paleogeography and coal accumulation of the Carboniferous-Permian paralic coal measures based on data from outcrop and borehole sections. The sequence boundaries were represented by regional disconformity, transgression direction switching surface, the base of incised valley fill sandstone, facies-reversal surface and associated paleosols. According to these sequence boundaries, the coal measures were subdivided into 7 third-order sequences and related systems tracts. For the paleogeography analysis, the contours of a variety of lithofacies parameters were drawn, including strata thickness, thickness ratio of sandstone and mudstone, limestone contents, and coal thickness. Based on these contours, the lithofacies paleogeography maps of each third-order sequence were reconstructed. The comparison of the contours of coal thickness with the distribution of facies units of the lithofacies paleogeography was made, and it revealed that the favorable coal-accumulating environments were deltas, fluvial plain and lagoon-tidal flat. Coal accumulation was strong in SQ2 (middle and upper Taiyuan Formation) and SQ3 (Shanxi Formation) with the coal accumulating centers were distributed in the Zhungeer, Datong, Shuozhou, Wuhai, Fengfeng areas, and the Beijing-Tainjin-Tangshan area. Coal accumulation in SQ4 (Xiashihezi Formation) and SQ5 (first member of the Shangshihezi Formation) was weak and the coal-accumulating centers were distributed in the southern part of the North China Basin, including Huainan and Huaibei coal fields. [ABSTRACT FROM AUTHOR]

Objective: To investigate the influence of escharectomy at different time-points after burn injury on the lymphocyte apoptosis and the antigen presentation function of monocytes in peripheral blood of scalded rats., Methods: One hundred and thirty-six Wistar rats were randomly divided into normal control ( C,n = 8 ), scald ( S, n = 64,without treatment after scald) , A ( n = 40, with escharectomy at 36 post-burn hour( PSH) ) , B ( n = 24, with escharectomy at 72 PSH ) groups. The rats in A , B, S groups were inflicted with 30% TBSA full-thickness scald. The rats in S group were sacrificed on 6,12,24,72,120,168,216, 288 PSH, while those in A and B groups were sacrificed at 72 -288 PSH, 168 -288PSH, respectively. The rats in C group were also sacrificed as control. The apoptotic rate of peripheral lymphocytes, the positive expression rate of MHC- II in mononuclear cells, the changes in concentration of IL-4 and gamma-IFN were determined in each group. The correlation of above indices were also analyzed., Results: (1) The apoptotic rate of peripheral lymphocyte in S group were increased dramatically at 6PSH, peaking at 24 PSH( 18. 19+/-1.42% ) , then decreasing gradually, reaching the lowest level at 72 PSH(8. 25+/-0.56% ) , then it increased gradually again, approaching almost the peak value at 288 PSH( 17.81 +/- 1.99% ). The values were all obviously higher than those in C group( P <0.05). The apoptotic rates of peripheral lymphocyte in A and B groups were evidently lower than that in S group ( P <0. 01). (2) The positive expression rate of MHC-II in monocyte was decreased sharply at 6 PSH, and it was 20% lower than that in C group (37. 2 +/- 2. 4% ) at 24 PSH. It then increased gradually, but it was significantly lower than that in A, B groups at 288 PSH (18. 8 +/-2. 8, P <0.01). (3) The plasma level of y-IFN in S group increased gradually from 6 PSH on, peaking at 24 PSH(440. 8 +/-25. 1 )ng/L,then decreasing gradually , and it reached the lowest level at 288 PSH (51.3 +/-37.0) ng/L. The IL-4 level in S group was increased gradually ,peaking at 288 PSH (78. 1+/-2. 8) ng/L. (4) There was negative correlation between the expression rate of MHC- II in S group and IL-4/gamma-IFN ratio in escharectomy groups during 72 - 288 PSH ( r = - 0. 96, P < 0. 05)., Conclusion: Eacharectomy after scald can inhibit peripheral lymphocyte apoptosis, slow down the insertional tendency of IL-4/gamma-IFN , and ameliorate the antigen presentation function of monocytes. Moreover, escharectomy during shock stage can markedly promote the immune function of monocytes.