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At present, optimization of mechanical properties in quenching and partitioning (Q&P) steels relies primarily on the tailoring of microstructural characteristics by manipulating the alloying elements and the Q&P process. However, adjusting the final microstructure by taking advantage of the inheritance effect derived from the initial microstructure has received less attention. Based on a typical Fe–C–Mn–Si system, the present investigation explores the effect of microstructural inheritance in an ultrahigh strength hot-rolled Q&P steel. The typical hot rolling process is followed by three cooling rates, including quenching, air cooling, and coil cooling, to obtain different initial microstructures of full martensite, bainite–austenite, and ferrite–pearlite, respectively. The same Q&P treatment is then performed to elucidate the inheritance mechanism, and the final Q&P products consist of different fractions of tempered martensite, retained austenite, bainite and fresh martensite. With decreasing cooling rates after hot rolling, the ultimate tensile strengths of the steels after the Q&P treatment are identical at ~ 1.5 GPa, while the total elongations increase gradually from 10.9, 12.7 to 14.5 pct. The highest elongation of the coil-cooled Q&P steel can be attributed to the effect of microstructural inheritance on the Q&P process and retained austenite, leading to larger austenite grain sizes and more equiaxed morphologies. The combination of austenite chemistry and morphology results in the optimal mechanical stability for retained austenite to provide continuous and durable strain hardening. Compared to cold-rolled products, hot-rolled Q&P steel is very attractive to the industry as it can potentially eliminate the cold rolling step and reduce the production cost. Utilizing the microstructural inheritance effect provides a simple and feasible route to control the microstructures and mechanical properties of ultrahigh strength hot-rolled Q&P steel.

The top eigenpairs at the title mean the maximal, the submaximal, or a few of the subsequent eigenpairs of an Hermitizable matrix. Restricting on top ones is to handle with the matrices having large scale, for which only little is known up to now. This is different from some mature algorithms, that are clearly limited only to medium-sized matrix for calculating full spectrum. It is hoped that a combination of this paper with the earlier works, to be seen soon, may provide some effective algorithms for computing the spectrum in practice, especially for matrix mechanics.

In this paper, we consider the time optimization problem of MCS (mobile crowd sensing). We consider the influence of various factors on time from two aspects of system task scheduling and task allocation. In task scheduling, we use queuing theory and data calculation to describe the optimal situation. In task allocation, we consider the reliability of tasks and the mobility of participants, Finally, the SA(simulated annealing) algorithm is compared with the greedy algorithm to prove the superiority of the algorithm.

In this paper, we consider a strategy for classifying tasks based on perceptual attributes and selecting participants based on perceptual attributes. In the covert of the classification task using the Latent Dirichlet Allocation (LDA) distribution, defined tasks according to the function of using sensors required for all kinds of attributes, the MCS system by sensing properties and energy consumption for the choice of participants, the participants set can meet the task of all sensory attributes, Our goal is to select participants to improve task completion while reducing overall system energy consumption. According to the perceptual attributes of tasks and the relationship between participants' energy consumption and task completion rate, a heuristic algorithm is proposed to solve these problems. Simulation results show that this algorithm is superior to other algorithms.

In this study, a long stroke atomic force microscope (LS-AFM) has been developed for the measurement of the micro-optics which have micrometric amplitude surface structures. An electrochemically polished tungsten wire is used as the AFM probe tip. Since the effective length of the tungsten probe is more than 100 μm, the probe tip can access valley part without the interference between the steep slope and the sidewall of the probe tip. By using the long stroke PZT Z scanner whose long stroke of 70 μm and a resolution of 1 nm, micrometric amplitude of the optical elements can be measured. A linear encoder is employed to measure the displacement of Z scanner in Z direction. A well-detected result of a prism sheet film profile has been obtained by the LS-AFM and its tapping mode.

An identification method of a class of second-order continuous system is proposed. This method constructs a discrete-time identification model, forms a set of linear equations. The parameters can be obtained by least square method. Simulation results show that the method is effective for a class of second-order system, and is not only for step response but also for square wave signal.

The function of three fields coupling of water-heat-mechanics is derived and established. The finite difference software FLAC3D is applied to simulate the affection of three fields coupling of water-heat-mechanics of the slope in the saturated state. The mechanism of instability and failure of the slope is revealed from two aspects like freezing depth and frost heaving deformation in the condition extreme snow hazard. The results show that freezing only occurs on the slope surface in the short time which makes no affection on the deep part; with the time lapsed the temperature in each depth decreases gradually and additionally with the increasing of the depth the effect of the surface temperature slows down. In the shallow part the temperature declines with the surface temperature declining and slows down with the increasing of depth. In the process of freezing the displacements occur on the surface to the direction of free boundary. In addition, the frost displacements increase with the time lapsing.

Background/Objectives: Free radicals and reactive oxygen species (ROS), which are generated by UV irradiation, may induce an irreversible growth arrest similar to senescence. Tiron, 4,5-dihydroxy-1,3-benzene disulfonic acid, is a widely used antioxidant to rescue ROS-evoked cell death. The aim of the article was to explore the effects of tiron on skin photoaging and associated mechanisms. Methods: The effects of tiron on cell proliferation were determined using 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide. Senescent cells were determined by morphology and senescence-associated β-galactosidase activity analysis. Intracellular hydrogen peroxide, superoxide anion and glutathione concentration were analysed by a fluorescent probe. The concomitant changes of protein expression were analysed with Western blot. Results: Human dermal fibroblasts were induced to premature senescence by sub-cytotoxic doses of irradiated UVB. Strong senescence-associated β-galactosidase activity and increased intracellular superoxide anion were observed in human dermal fibroblasts irradiated by UVB. Tiron blocks UVB-induced glutathione depletion and increase of superoxide anion and protects against UVB-induced senescence-like characteristics in human dermal fibroblasts. Compared with normal fibroblasts, UVB-irradiated human dermal fibroblasts showed a higher ratio of active (hypophosphorylated) to inactive (phosphorylated) forms of Rb and p38, upregulation of p53 or p16 and c-Myc and insulin-like growth factor 1 (IGF-1) downregulation. After treatment with tiron, p53, p16 c-Myc and IGF-1 as well as phosphorylation Rb and p38 could partially recover. Conclusion: These results indicate that tiron protects against UVB-induced senescence-like characteristics in human dermal fibroblasts via the inhibition of production of superoxide anion and glutathione depletion, and modulation of related senescence proteins.

Porous silver-modified ZnO microrods photocatalysts were synthesized through direct thermal decomposition of the Ag-doped zinctartrate precursor, which was prepared by homogeneous precipitation method at 80 °C for 2 h. The obtained samples were characterized by XRD, FTIR, TG-DTA and UV-VIS absorption spectroscopy. The photocatalytic activity of the as-prepared porous Ag/ZnO microrods was tested with the photocatalytic degradation of methyl orange. The results indicate that doping Ag greatly improves the photocatalytic efficiency of ZnO and 3% Ag-doped (mole fraction) ZnO porous microrod photocatalyst exhibits the highest photocatalytic decolorization efficiency, leading to as much as 80% reduction of MO concentration in 120 min. Moreover, the 3% Ag-doped porous microrods also possess higher photocatalytic activity under the real sunlight irradiation.

A new improved multidiscipline feasible (MDF) strategy based on the updating approximate function constructed by Response Surface Method (RSM) is firstly pointed out and denoted as MDF-update-RSM which involves double cycles. Before the start of inner loop on MDF-update-RSM strategy, the approximate function is initialized by RSM on a set of sampling points which are generated from the Design of Experiment (DOE). With the process of outer loop, the coefficients and one high-order term of polynomial are updated and upgrade by the Least Square Regression. The ability of this new strategy promotes the efficiency and saves huge calculational cost incurred by the MDF strategy which always runs on the multidisciplinary analysis (MDA). The MDF-update-RSM is good procedure to ameliorate the accuracy that has been tested by the Rosenbrock function in this paper. Finally, the optimization strategy is employed on executing the low pressure turbine shrouded blade design and provides a true optimal result compared to the classical MDF strategy.

A series of V-Cr/SBA-15/Al2O3/FeCrAlmetal monolithic catalystswithV content of 10wt% and Cr contents from 0 to 12.5wt% were prepared. The structure of the catalysts was characterized using XRD, XPS and TPR techniques. The catalytic activity for oxidative dehydrogenation (ODH) of propane with CO2was evaluated. The results indicate that the mesoporous structure of SBA-15 was retained after vanadium and chromium incorporation and the vanadium species were well dispersed. The V-Cr/SBA-15/Al2O3/FeCrAl catalyst with 10wt%V and 10 wt% Cr exhibited the best activity with a propane conversion of 49.9% and a propylene selectivity of 86.5% at 650 °C.

Magnetic γ-Fe 2 O 3 /activated carbon microspheres have been synthesized by an activation process of carbon microspheres containing iron oxides, which were prepared by hydrothermal method. The structure and morphology of the magnetic porous carbon microspheres were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), thermogravimetry and differential thermal analysis (TG-DTA) and N 2 adsorption–desorption technique. The results showed that the as-prepared activated carbon spheres were the composite of single-phase γ-Fe 2 O 3 and activated carbon material, and the content of carbon was about 3.87%. Using methyl orange as model pollutant, the magnetic porous carbon microspheres showed good adsorption capacities of 44.65 mg/g. The isotherm evaluations revealed that the Langmuir model attained better fits to the experimental equilibrium data than the Freundlich model. These magnetic porous carbon microspheres could potentially be applied in separation processes.

Magnetic mesoporous Mn-Fe oxide catalyst with high surface area was prepared by calcining the corresponding oxalate precursor. The calcined sample was characterized by XRD, FTIR, N2 adsorption, TEM, and SEM. The catalytic property of the porous Mn-Fe oxide catalyst was evaluated by catalytic decolorization of methyl orange (MO). XRD, SEM, and TEM analysis and N2 adsorption–desorption isotherm revealed mesoporous Mn-Fe oxide strucutre with high-surface area and uniform pore-size distribution. The results of catalytic performance measurements showed that the Mn-Fe binary oxide was an effective catalyst. The as-prepared catalyst could be recycled as a magnetically separatable catalyst to treat dye-containing wastewater.

Free radicals and reactive oxygen species (ROS), which are generated by UV irradiation, may induce an irreversible growth arrest similar to senescence. Tiron, 4,5-dihydroxy-1,3-benzene disulfonic acid, is a widely used antioxidant to rescue ROS-evoked cell death. The aim of the article was to explore the effects of tiron on skin photoaging and associated mechanisms. The effects of tiron on cell proliferation were determined using 3-(4,5-dimethylthiazol-2-Yl)-2,5-diphenyltetrazolium bromide. Senescent cells were determined by morphology and senescence-associated β-galactosidase activity analysis. Intracellular hydrogen peroxide, superoxide anion and glutathione concentration were analysed by a fluorescent probe. The concomitant changes of protein expression were analysed with Western blot. Human dermal fibroblasts were induced to premature senescence by sub-cytotoxic doses of irradiated UVB. Strong senescence-associated β-galactosidase activity and increased intracellular superoxide anion were observed in human dermal fibroblasts irradiated by UVB. Tiron blocks UVB-induced glutathione depletion and increase of superoxide anion and protects against UVB-induced senescence-like characteristics in human dermal fibroblasts. Compared with normal fibroblasts, UVB-irradiated human dermal fibroblasts showed a higher ratio of active (hypophosphorylated) to inactive (phosphorylated) forms of Rb and p38, upregulation of p53 or p16 and c-Myc and insulin-like growth factor 1 (IGF-1) downregulation. After treatment with tiron, p53, p16 c-Myc and IGF-1 as well as phosphorylation Rb and p38 could partially recover. These results indicate that tiron protects against UVB-induced senescence-like characteristics in human dermal fibroblasts via the inhibition of production of superoxide anion and glutathione depletion, and modulation of related senescence proteins.