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High strain hardening rate is usually pursued for high ductility. Here we report that moderate strain hardening rate is desired for producing better ductility and high yield strength, which is demonstrated in a medium carbon TRIP steel. By adjusting the temperature for bainitic transformation, the morphology, carbon content and residue stress of retained austenite were tuned to tailor the TRIP kinetics during tensile tests, which produced moderated but long-lasting strain hardening for high ductility while at the same time resulted in high yield strength. This strategy should work well for most materials, which usually have a limited ultimate strength. A principle is proposed and verified that an optimized moderate strain hardening rate is desired to produce the best mechanical properties for metallic materials.

In this paper, Ti6Al4V+3 wt.% TiB2 composite powder was used as a raw material to synthesize TiB whiskers in situ and prepare composites reinforced with TiB/Ti6Al4V whiskers by selective laser melting (SLM). The effects of process parameters on the properties of TiB/Ti6Al4V samples were systematically studied. The evolution of the microstructure, including the formation and regulation of whiskers, and the effects on mechanical properties were discussed. The results showed that during the SLM process, adjusting the energy density effectively inhibited cracking in the TiB/Ti6Al4V samples. The TiB2 particles acted as nucleation centers to significantly refine the grains during processing and reacted with elemental Ti to form a needle-like TiB network at the grain boundaries, which strengthened the whiskers. Additionally, TiB played a role in dispersion strengthening. Compared with Ti6Al4V, the microhardness of TiB/Ti6Al4V was 430.6?11.45 HV, an increase of 27.9%, and the wear volume of the sample was 0.85?10-3 mm3, a decrease of 62.64%.

To study the effect of atorvastatin on pulmonary hypertension (PAH) rats through regulating the Notch signaling pathway.The rat model of PAH was established via hypoxic feeding and the Control group (n=10), PAH model group (Model group, n=10) and atorvastatin treatment group (ATO group, n=10) were set up. The right ventricular systolic pressure (RVSP) and right ventricular hypertrophy index (RVHI) in each group were determined, the wet/dry weight (W/D) ratio of lung tissues was determined, and the tumor necrosis factor-α (TNF-α), myeloperoxidase (MPO) and interleukin-6 (IL-6) were detected via enzyme-linked immunosorbent assay (ELISA). Moreover, the pathological changes in lung tissues of rats were detected via hematoxylin-eosin (HE) staining and the apoptosis level was detected via terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay. Finally, the Notch signaling pathway and apoptosis level in tissues were detected via quantitative Polymerase Chain Reaction (qPCR), and the protein expression level of Notch pathway in lung tissues was determined through Western blotting.Both RVSP and RVHI in Model group were significantly higher than those in Control group and ATO group (p0.05). In Model group, the levels of inflammatory factors MPO, IL-6, and TNF-α were significantly increased, and the W/D ratio was also significantly increased compared with those in Control group (p0.05). The results of HE staining showed that the lung tissue injury in Model group was severe (p0.05). According to the TUNEL staining results, the number of apoptotic cells in lung tissues was markedly larger in Model group than that in ATO group (p0.05), and the expression levels of Caspase-3 and IL-6 in Model group were remarkably higher than those in ATO group (p0.05), while the expression level of B-cell lymphoma-2 (Bcl-2) in Model group was remarkably lower than that in ATO group (p0.05). Besides, the gene and protein expression levels of Notch1 in ATO group were evidently lower than those in Model group (p0.05), indicating that atorvastatin can effectively suppress the expression of Notch.Atorvastatin can inhibit PAH in rats by suppressing the Notch pathway.

Mg alloys are among the lightest alloys but they are usually weak. Here we report a new mechanism to make them ultrastrong while maintaining good ductility. Stacking faults with nanoscale spacing were introduced into a Mg–8.5Gd–2.3Y–1.8Ag–0.4Zr (wt%) alloy by conventional hot rolling, which produced a yield strength of ∼575 MPa, an ultimate strength of ∼600 MPa, and a uniform elongation of ∼5.2 %. Low stacking fault (SF) energy enabled the introduction of a high density of SFs, which impeded dislocation slip and promoted dislocation accumulation. These findings provide guidance for developing Mg alloys with superior mechanical properties.

The aim of this study is to investigate the role of complement-neutrophil feedback regulation of inflammatory response in Henoch-Schönlein purpura (HSP) through constructing an animal model of HSP.Twenty-four SPF grade Japanese large-eared white rabbits were randomly divided into normal group and model group, 12 for each group. HSP model was constructed by challenging rabbits with gastric gavage of a decoction solution containing ginger, Piper longum L. and pepper, intraperitoneal injection of ovalbumin (OVA)-Freund's adjuvant and intravenous injection at marginal ear vein and subcutaneous injection in the back of rabbits with OVA normal saline solution. Changes in general conditions of rabbits including food intake, water intake and body temperature as well as alterations in blood routine, urine routine, reactive oxygen species (ROS), inflammatory cytokines and complement were compared between two groups. In the meantime, N-Acetyl-L-Cysteine (NAC)and hydrogen peroxide (H2O2) treatment was used to manipulate ROS level and determined the changes in aforementioned parameters.After sensitization, rabbits of the model group displayed significantly elevated body temperature, apathy, reduced physical activity, significantly decreased water and food intake compared to the situations before sensitization (p0.05). Significant pathological changes were observed in these rabbits through HE staining study. Furthermore, blood levels of white blood cells (WBC), mean corpuscular hemoglobin concentration (MCHC), neutrophils (NEU) and NEU% were significantly increased, whereas levels of red blood cells (RBC), hemoglobin (HGB), eosinophils (EOS) and EOS% were significantly decreased (p0.05). No significant alterations were observed in levels of mean corpuscular hemoglobin (MCH) and platelet (PLT) (p0.05). Urine with mucus and a strong odor was observed in model rabbits. Proteinuria occurred in 66.67% of model rabbits, hematuria in 58.33% and presence of WBC in the urine in 25%. Also, levels of ROS, inflammatory cytokines, tumor growth factor (TGF)-β, complement and tumor necrosis factor (TNF)-α were significantly increased in model rabbits. After the treatment of ROS inhibitor, NAC, levels of these parameters were significantly decreased (p0.05), but significantly increased after treatment of H2O2, the ROS agonist (p0.05).Complement-neutrophil feedback regulation of inflammatory response plays important roles in the pathogenesis of HSP, and inhibition of ROS can suppress the development and progression of HSP.

Two series of novel polysulfone-based ionomers containing pendant sulfonic acid groups (designated as PSf-sph-y and PSf-sna-z) have been prepared using commercially available polysulfone and sulfoaryl monomers. The synthesized ionomers have been characterized by nuclear magnetic resonance, differential scanning calorimetry, and thermogravimetric analysis. The thermal characterization data show that these polymers are stable up to 210 °C in acid form and 270 °C in salt form in air. Ion exchange capacity, water uptake, swelling, proton conductivity, and methanol permeability of the membranes have been investigated and compared with those of Nafion 115. The PSf-sna-z membranes bearing highly ionic groups on the flexible side chains show lower water uptake, swelling, and methanol permeability compared to the PSf-sph-y and Nafion 115 membranes. The optimized PSf-sna-58 membrane shows better performance in direct methanol fuel cells (DMFC) than Nafion 115 membranes.

The inclusive reduced velocity correlation functions of the intermediate mass fragments were measured in the reactions of 36Ar + 112,124Sn at 35 MeV/u. The anti-correlation is observed to be stronger in 36Ar + 124Sn system than that in 36Ar + 112Sn. The difference of the correlation functions between the two reactions is mainly contributed by the particle pairs with high momenta. A three body Coulomb repulsive trajectory model is employed to calculate the emission time scale of the IMFs for the two systems. The time scale is 150 fm/c in 36Ar + 112Sn and 120 fm/c in the 36Ar + 124Sn, respectively.

Isotope ratios, as a function of kinetic energy in units of MeV/u of outgoing particles, are analyzed at 20° in the reaction of 40 Ar+ 112,124 Sn and 5° in 36 Ar+ 112,124 Sn at incident energy of 35 MeV/u. Relative yield ratios to stable isotopes increase with kinetic energy for the isotopes with low N / Z ratio but decrease for those with high N / Z ratio. This different behavior shows evidence of isospin non-equilibrium in dissipative projectile emission processes. It is demonstrated that the time of isospin relaxation is shorter as or comparable with that of energy relaxation in these reactions. Double isotope-ratio temperature parameters, extracted in the 36 Ar induced reaction from projectile-like fragments, also support the non-equilibrium of isospin or/and temperature degrees of freedom.

The variation with temperature of oxygen content in the electron-doped superconductors Ln 2- x Ce x CuO 4 ( Ln = lanthanide) have been investigated systematically by thermogravimetric analysis. The tendency to lose oxygen generally decreases with increasing Ce content or decreasing Ln 3+ size due to a decreasing degree of internal stresses resulting from an improved bond length matching between the ( Ln , Ce)-O and Cu-O bonds; this is supported by bond valence sum calculations. With smaller a lattice parameters as in Gd 2- x Ce x CuO 4 , however, an increasing electrostatic repulsion between the interstitial octahedral-site and the normal tetrahedral-site oxygen atoms forces the excess interstitial oxygen atoms to be lost at lower temperatures. It also causes the oxygen loss to occur in two steps, one corresponding to the interstitial oxygen and the other to the tetrahedral-site oxygen atoms. In contrast, the oxygen loss occurs smoothly in one step for larger a lattice parameters as in LaNd 1- x Ce x CuO 4 .

A theory to analyse the strength of composite materials with randomly oriented short fibres has been developed. The short fibres are assumed to be uniformly distributed and randomly oriented in three dimensions. The non-homogeneous deformation within the composite has been taken into account in the strength calculation. The influences of thermal stress in the short fibres, the short-fibre dispersion hardening and the dislocation density in the matrix on the composite strength have all been estimated, and the strengthening mechanisms involved are discussed. A comparison with previous strength theory suggests that the present theory gives a better agreement with experimental data, and can be used to explain some experimental phenomena that remain unsolved.

The electron doped Ln2−xCexCuO4 (Ln=lanthanide) oxides have intergrowth structures consisting of superconductively active CuO2 sheets alternating with inactive (Ln, Ce)2O2 fluorite layers along the c-axis. Stabilization of such intergrowth structures requires bond length matching across the intergrowth interface. The bond length matching criterion causes a monotonic decrease in the Ce solubility limit from x=0.24 to x=0.15 as the size of Ln3+ decreased from Ln=La0.5Nd0.5 to Ln=Gd. Annealing in N2 atm of Ln2−xCexCuO4 at temperatures above 900°C creates oxygen vacancies and the number of vacancies decreases with increasing Ce content. The value of x at which a semiconductor to superconductor transition occurs in Ln2−xCexCuO4 increases with decreasing size of Ln3+ due to an increasing Madelung energy caused by a decreasing Cu−O bond length.

The magnitude 8.0 Ms Wenchuan earthquake of 12 May 2008 occurred along the Longmen Shan fault zone, southwest of China, is a huge hazard. Why the earthquake is happened along the NE-SW tending and in an inactive orogenic area? What is the geodynamics caused the earthquake erupting abruptly? Usage of the results of the processing and interpretation of the magnetotelluric data observed before the Wenchuan earthquake from Luqu-Zhongjiang passed through the Qinling tectonic zone, Songpan-Garze block and Longmen Shan as well as Sichaun basin, this paper reveals crustal architecture of 50 km depth of the Eastern Qinghai-Tibet plateau and Western Sichuan foreland basin and the relationship between them, with the characteristics of eastern pressing of the Qinghai-Tibet plateau forcing Songpan-Garze block thrusting upon the Yangzi continent block, later obstructing the eastern movement of the Qinghai-Tibet Plateau. The Longmen Shan is located at the joint of two block and has been found there is a west inclined low-conductivity layer in the crust of 10-20 km depth of Longmen Shan, it is deduced as the deep conductivity characteristics of thrustbelt structure in Longmen Shan. The huge earthquake has caused about 300 kilometers long rupture zone,it happened mainly in faults of Beichuan-Yingxiu and Pengxian-Guanxian of Longmen Shan faults setup, which is going down with the north-western inclined along the thrustbelt in the Longmen Shan. The two faults of Beichuan-Yingxiu and Pengxian-Guanxian seem going to converge together at the deep but they are probably separated with the Maoxian-Wenchuan fault in the Longmen Shan structure zone. There are a little different characters for the Sichuan basin and the Songpan-Garze foldbelts located at the two side of the Longmen Shan, for Sichuan basin has the characteristics of the upper thick low resistance sedimentary, and the under stable high resistance basement, while Songpan-Garze block has high resisitivity cover of upper crust with continuous low resistance bed of the crust. Resulting from the Songpan-Garze block thrust upper the Sichuan Basin stability block, the Longmen Shan structure zone formed three layer of geoelectrical structure which is a high resistance in the upper and lower part of high resistance basin basement, and mingling with low resistance thrust fault zone in the middle. As explanation above, the conclusion could be focused on (1) there is a western inclined thrusting zone range from surface to depth 20km or more under Longmen Shan and Songpan Block, which caused the earthquake happen as it be activated; (2) the different action of surface breaking of Longmen Shan thrusting faults depend on the deep structure characteristics; (3) the earthquake is caused by the mutually promotive with Eurasian plate, Indian plate and Pacific plate in a broad sense. So the research on the MT profile is important for both continent dynamics in the orogenic zone and deep mechanism of Wenchuan earthquake at Longmeshan fault zone in the east of the Qinghai-Tibet plateau.

We report measurements on the length-dependent thermal conductivity of individual single-walled carbon nanotubes (SWNTs) on a substrate using a four-pad 3ω method with the consideration of heat loss between the sample and substrate. An increase in thermal conductivity with length (0.5—7μm) was observed at room temperature. The length-dependence of thermal conductivity was theoretically predicted by the modified WV model with consideration of second order-3-phonon process. The predicted phonon mean free path is about 175nm. Both the measurement and the prediction show the scale effect of the length on the thermal conductivity of SWNTs.