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By means of direct aged treatment, creep property measurement and high resolution TEM microstructure observation, the deformation mechanisms of Tandem Hot Rolled GH4169 superalloy during creep are investigated. Results show that, after direct aging treatment, fine γ″ particles with different sizes and shapes dispersedly precipitate in the alloy, which is one of important factors for the alloy possessing good creep resistance. And the deformation mechanisms of the alloy are that the deformed twinnings with different orientations are activated on {111} plane by pole mechanism, thereinto, the twinning dislocation may continuously slip around a pole axis dislocation on the twinning planes when the applied stress exceeds the critical value, and the twinnings may multiply by the dislocation reactions and mutual indemnification. As creep goes on, the denser dislocations with single or double orientations slip in the different twinnings, which play an important role of coordinating the grain deformation to enhance the creep resistance of the alloy.

Cornstalk-based MnO2 nanoparticles (MnO2 NPs) were synthesized from KMnO4 through an in situ redox reaction. The synthesis was performed under an open system and did not need complicated apparatus, giving its advantages of easy operation, low cost and green synthesis. Combining the adsorption capacity with oxidation activity, the as-prepared cornstalk-based MnO2 NPs were applied to methylene blue (MB) decontamination. It was demonstrated that the removal efficiency was 79.88% in 60[Formula: see text]min by adsorption in water and reached up to 95.16% in pH [Formula: see text] 3 buffer with the help of oxidation. Most importantly, the decontamination materials could be separated simply by taking them out from MB solutions during the monitoring process or after treatment, avoiding the fussy centrifugation or filtration. This advantage endows the cornstalk-based MnO2 NPs superiority and would raise concerns in water decontamination.

The Pearl River Estuary (PRE) is a window into the drastic changes that occurred throughout coastal areas due to artificial agglomeration following China’s 1978 economic reform. In this study, multi-temporal Landsat remote sensing images were used to extract coastlines in the PRE with the support vector machine (SVM). In addition, the coastline was divided into nine segments by using the eight mouths as the cut-off points. A statistical analysis was performed on the length and changes of each coastline segment. The analysis was focused on the five shores that exhibited obvious changes. Subsequently, a correlation analysis between three artificial development factors, namely, the development intensity, development speed, and development density, and the shoreline length was conducted, following which the main driving factors influencing the changes in the coastline were obtained. Finally, the dynamic processes and artificial mechanisms of the coastline changes in the PRE were deeply analyzed. The results reveal that the coastline has been gradually advancing over a distance of 164.01 km toward the sea over the past 40 years, and the growth rate initially showed a rapidly increasing trend in 1978 but has since slowed from 1998 to the present. The most significant changes were detected along the Hutiao Men–Jiti Men and Jiti Men–Modao Men shore areas due to the impacts of human activities. The development speed presented dominant influence on coastline change at the end of the 20th century, but the development intensity was the primary influence factor during the early 21st century. To a certain extent, the monitoring and analysis of historical coastline changes can contribute to coastal zone planning in more detail, thereby promoting the sustainable development of coastal zones.

In order to purify phosphoric acid hemihydrate (H3PO4·0.5H2O) crystal further, the effects of sweating time and sweating temperature on purification are investigated in a dry-sweating process. Experimental results indicate the content of Mg, As, Sb and Pb in the H3PO4·0.5H2O crystal decreases with increasing sweating time and sweating temperature during sweating process and show the same tendency to decrease with time at different sweating temperatures. The purification rate coefficients of H3PO4·0.5H2O crystals for Mg, As, Sb and Pb are determined. They increase with an increase in sweating temperature. The Arrhenius equation can be successfully used to describe the relationship between the purification rate coefficient and the absolute sweating temperature. The activation energy of sweating for Mg, As, Sb and Pb in the H3PO4·0.5H2O crystal are calculated using these experimental data. These values for Mg, As, Sb and Pb are 130.13, 193.59, 98.51 and 102.29 kJ mol−1, respectively.

Hydroxysafflor yellow A (HSYA), a major constituent in the hydrophilic fraction of the safflower plant, can retard the progress of hepatic fibrosis. However, the anti-inflammatory properties and the underlying mechanisms of HSYA on I/R-induced acute liver injury are unknown. Inhibiting macrophage activation is a potential strategy to treat liver ischemia/reperfusion (I/R) injury. In this study, we investigated the therapeutic effect of HSYA on liver I/R injury and the direct effect of HSYA on macrophage activation following inflammatory conditions. The therapeutic effects of HSYA on I/R injury were tested in vivo using a mouse model of segmental (70%) hepatic ischemia. The mechanisms of HSYA were examined in vitro by evaluating migration and the cytokine expression profile of the macrophage cell line RAW264.7 exposed to acute hypoxia and reoxygenation (H/R). Results showed that mice pretreated with HSYA had reduced serum transaminase levels, attenuated inflammation and necrosis, reduced expression of inflammatory cytokines, and less macrophage recruitment following segmental hepatic ischemia. In vitro HSYA pretreated RAW264.7 macrophages displayed reduced migratory response and produced less inflammatory cytokines. In addition, HSYA pretreatment down-regulated the expression of matrix matalloproteinase-9 and reactive oxygen species, and inhibited NF-κB activation and P38 phosphorylation in RAW264.7 cells. Thus, these data suggest that HSYA can reduce I/R-induced acute liver injury by directly attenuating macrophage activation under inflammatory conditions.

Long-term inhalation of gasoline engine exhaust (GEE) increases the risk of respiratory disease. Studies have suggested involvement of platelets in the development of some lung diseases. Hydroxysafflor yellow A (HSYA), a flavonoid compound, prevents hemostasis. Therefore, we investigated its effects on GEE-induced lung injury, and role of platelets in injury. Sixty-week-old male Sprague-Dawley rats were exposed to GEE for 4h/day for 6 weeks, and then grouped as follows: control, GEE, GEE+HSYA, GEE+HSYA+GW9662, and GEE+GW9662. Arterial oxygen tension (PaO2), carbon dioxide tension (PaCO2), pH, and the PaO2/fraction of inspired oxygen ratio (PaO2/FiO2) in the blood were detected using a blood gas analyzer. Wet/dry lung weight ratio, total protein in bronchoalveolar lavage fluid (BALF), and cytokine concentrations in serum and BALF were determined. Furthermore, cyclic adenosine monophosphate (cAMP) level and expression levels of target proteins were analyzed. Platelets were counted and their state was evaluated. HSYA attenuated GEE-mediated decreases in PaO2, PaO2/FiO2, platelet cAMP level, protein kinase A (PKA) activity, and peroxisome proliferator-activated receptor γ (PPARγ) expression. HSYA also attenuated GEE-mediated increases in lung permeability, cytokine levels in serum and BALF, plasma platelet count, and ADP-mediated platelet aggregation. Moreover, it suppressed GEE-induced increases in the expression of adhesion molecules and proinflammatory cytokines in platelets and lung tissue. Therefore, HSYA is therapeutically effective for GEE-mediated lung injury and acts by enhancing PKA activity and inhibiting platelet activation.

InAlN/GaN high-electron mobility transistors (HEMTs) with a gate length of 100 nm and oxygen plasma treatment were fabricated. A Si/Ti/Al/Ni/Au ohmic contact was also used to reduce the contact resistance. DC and RF characteristics of the devices were measured. The fabricated devices show a maximum drain current density of 2.18 A/mm at VGS = 2 V, a low on-resistance (Ron) of 1.49 ωmm and low gate leakage current. An excellent frequency response was also obtained. The current cut-off frequency (fT) is 81 GHz and the maximum oscillation frequency is 138 GHz, respectively.

This research aims to seek a better early warning evaluation index system of enterprise purchasing risk. Based on the basic principle of the Balanced Scorecard (BSC), a feasibility of applying the BSC in early warning evaluation of enterprise purchasing risk is analyzed first. Secondly, risks in enterprise procurement and their respective influencing factors are proposed from the perspectives of finance of purchasing, purchasing performance, internal operation of purchasing and purchasing future development. Also, an early warning evaluation index system of enterprise purchasing risk is constructed. And finally, the Fuzzy Analytical Hierarchy Process (FAHP) is introduced in the early warning evaluation index system of enterprise purchasing risk, which thus helps to strengthen the enterprise purchasing risk management.