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The solidification paths of Al-Zn-Mg alloys in the Al-rich corner were investigated. The thermodynamic data for the calculation are obtained by direct coupling with the CALPHAD software Thermo-Calc via its TQ6-interface and the COST2 database. The influences of the initial compositions and the extent of solid back diffusion on the solidification path were numerically investigated by sample calculation of the ternary Al-Zn-Mg alloys. The calculation results of solidification paths of the selected alloys: Al-5Zn-3Mg (in wt.%), Al-5Zn-10Mg, Al-2.5Zn-15Mg, Al-10Zn-20.5Mg, Al-8Zn-25Mg, were: L→(L+α-Al), L→(L+α-Al)→(L+α-Al+TAU), L→(L+α-Al)→(L+α-Al+AlMg_β), L→(L+α-Al)→(L+α-Al+TAU)→(L+α-Al+TAU+AlMg_β), L→(L+α-Al)→(L+α-Al+AlMg_β)→(L+α-Al+TAU+AlMg_β), respectively. The results show that the initial compositions and the extent of solid back diffusion have a great influence on solidification path, and the amounts of eutectic phase increase with the decrease of the solid back diffusion coefficient. The equilibrium solute partition coefficients for Zn and Mg in alloys are also calculated and their influence on micro-segregation in the primary solidification of Al-5Zn-10Mg alloy is analyzed.

Context:MicroRNA (miR)-146bis overexpressed in papillary thyroid carcinoma (PTC) and is associated with extrathyroidal invasion, advanced tumor stage, and poor prognosis. However, the underlying mechanism of miR-146bin relation to its oncogenic behavior in PTC and its putative targets remain unknown.Objective:The purpose was to investigate IL-1 receptor-associated kinase 1 (IRAK1) as the potential miR-146btarget gene and its involvement in PTC.Design:We used genome-wide microarray, computational analysis, and 3′ UTR reporter gene assays to identify IRAK1as a miR-146btarget gene. In vitro gain/loss-of-function experiments were further performed to determine the effects of IRAK1on proliferation, colony formation, and wound-healing in PTC cancer cell lines. Expression levels of miR-146band IRAK1of 50 cases of PTC and its adjacent normal thyroid specimens were assessed via qRT-PCR.Results:Microarray expression profile revealed that the mRNA level of IRAK1gene was down-regulated by miR-146b.The 3′ UTR of IRAK1mRNA was found to be a molecular target of miR-146bposttranscriptional repression in BCPAP cells by reporter gene assays. MiR-146bpromoted the migration and proliferation of PTC cells by down-regulating IRAK1expression, whereas restoration of IRAK1expression reversed this effect. In addition, the expression of IRAK1 mRNAwas significantly lower in PTC clinical tissue samples than normal adjacent thyroid specimens and showed a strong inverse correlation with the expression of miR-146bin PTC specimens.Conclusion:Our results demonstrated that IRAK1is a direct target of miR-146band has functional roles to inhibit various aggressive PTC cell activities. In conjunction with current therapeutic regimens, targeting the miR-146b-IRAK1axis may provide a potential approach for PTC management.

To investigate the effects of moxibustion on the serum metabolism in healthy human body based on the 1H nuclear magnetic resonance (1H NMR) metabolomics technology, and to find the differences in metabolites, as well as to elucidate the effects of moxibustion on healthy human body from the viewpoint of global metabolism. Sixty subjects of healthy young men from the enrolled students were randomly divided into a moxibustion group and a control group using random number table, with 30 cases in each group. Subjects in the moxibustion group accepted mild moxibustion on the right Zusanli (ST 36), once a day, 15 min for each time, and continuous treatment for 10 d; those in the control group did not receive any intervention. There were 28 cases in the moxibustion group and 23 cases in the control group after interventions. On the 1st day, 5th day and 10th day of the intervention, serum samples were collected from subjects of the two groups, and metabolic spectra were obtained by the 1H NMR technology. Before and after the intervention, serum 1H NMR of the moxibustion group was significantly different, while the difference was insignificant in the control group. Metabolite changes in the moxibustion group were mainly in low density lipoprotein (LDL)/very low density lipoprotein (VLDL), valine, isoleucine, leucine, lactic acid, glutamine, citric acid, polyunsaturated fatty acids, creatine, glycine, glycerol, glucose, tyrosine, histidine, formic acid, alanine, lysine, acetic acid, and glutamic acid. Moxibustion can cause changes of serum metabolic patterns in healthy human by influencing the concentrations of branched-chain amino acids, polyunsaturated fatty acids, and other metabolites to strengthen body's metabolisms of amino acids and fatty acid. 基于核磁共振氢谱代谢组学技术(1H nuclear magnetic resonance, 1H NMR)探讨艾灸对正常人体血清代谢的影响, 并寻找差异性代谢物, 从整体代谢的角度阐述艾灸对健康人体的影响。 将60 例在校健康青年男性采用随机数字表随机分成艾灸组和对照组, 每组30 例。艾灸组予温和灸右侧足三里, 每天1 次, 每次15 min, 连续治疗10 d; 对照组不予任何干预。干预结束后艾灸组剩余28 例, 对照组剩余23 例。在干预第1 d、第5 d 和第10 d, 采集两组受试者的血清样品, 运用1H NMR 技术获取代谢图谱。 艾灸组干预前后血清1H NMR 有明显差异, 对照组干预前后1H NMR 无明显差异。艾灸组代谢物的变化主要是低密度脂蛋白(low densitylipoprotein, LDL)/极低密度脂蛋白(very low density lipoprotein, VLDL)、缬氨酸、异亮氨酸、亮氨酸、乳酸、谷氨酰胺、柠檬酸、多不饱和脂肪酸、肌酸、甘氨酸、甘油、葡萄糖、酪氨酸、组氨酸、甲酸、丙氨酸、赖氨酸、乙酸、谷氨酸。 艾灸能够引起正常人体血清代谢模式变化, 通过影响支链氨基酸、多不饱和脂肪酸等代谢物浓度加强机体的氨基酸、脂肪酸代谢。

The thermal effect caused by absorbing inclusion irradiated by pulse laser is affected by size of inclusions, pulse duration, repetition interval and number of pulse laser. The temperature both in the center of inclusion and the interface between inclusion and dielectric increases firstly with the increase of the size of inclusion, then trends to a constant value when the size is over the critical radius. Pulse duration and repetition interval of pulse change the energy acumulation in inclusion then have influence on the peak temperature in the center and interface. The temperature fluctuates periodically but the overall assumes the trend of increase.

The high solid loading slurries with ZnO-Al2O3 powders stabilized with polyelectrolytes have been studied. The influence of Sodium poly(acrylate) (PA 30) on the fluidity and stablility of the slurries was investigated. Morphological features of ZnO-Al2O3 powders in suspension and fracture surface of green compact were observed using TEM and SEM. The slurries with pH 9 were prepared after milled using ZnO mixed powders and the PA 30 solution of pH 8. As 0.2 wt% PA 30 added, the lowest viscosity and the highest sediment were obtained. ZnO and Al2O3 particles had been homogeneous dispersed. The maximum density (66.7 %TD) of green compact was obtained.

With the development of transportation, subway is more and more important to every city, but the security of underground railway track faces with serious challenges. Tunnel excavation cross-section types have rectangle, roundness, arch, composite one and so on. In the tunnel excavation under Feng-tian Road in Chongqing, we chose three cross-section types for obtaining optimal scheme by finite element method (FEM). The efficiency and reliability of the optimized tunnel excavation cross-section were demonstrated by simulation results by FEM software Abaqus, and the tunnel excavation engineering under Feng-tian Road in Chongqing. Hope that this work can provide a reference to other tunnel excavation engineering.

Oxide-dispersion-strengthened (ODS) ferritic alloys are fascinating materials for future fusion power reactors due to these materials would allow a substantial increase of the operating temperature. Y-Ti bioxides strengthened Fe-Cr alloy was produced by mechanical milling (MM) followed by hot pressing (HP). Microstructure changes of the mixed powders during mechanical milling and subsequent hot pressing were structurally characterized by means of scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray diffraction (XRD). The observations of structure of the mixed powders after MM indicated that the powders are fractured and welded with rotation and vibration of container during mechanical milling. And the particle size decreases with increasing milling time. Nanoscale Y-Ti bioxides were formed during the HP process.

The thermal effect caused by absorbing inclusions irradiated by multi-pulse laser is different from that of single pulse laser. The temperature field induced by multi-pulse laser depends markedly on both inclusion size and pulse duration, and repetition interval of pulse. Based on the differential equation of heat conduction, the temperature field caused by single absorbing inclusion is solved by use of finite difference method. The effect of inclusion size, pulse duration and repetition interval of pulse on the evolution of temperature field at the center of inclusion and interface between inclusion and dielectric are discussed qualitatively.

The thermal effect arisen from absorbing inclusions is the main factor which causes the damage of optical materials or component irradiated by the longer pulse duration laser. The unsteady heat conduction depends markedly on both the thermal properties of inclusions and the parameters of laser. Based on the differential equation of heat conduction, the temperature distribution caused by single absorbing inclusion is solved by use of finite difference method. The effect of the laser intensity and the pulse duration on temperature field is analyzed in detail. The result demonstrates that the smaller size inclusion and the smaller pulse duration cause relative safe thermal effect, consequently, the less probability to be damaged by thermal effect.

Transparent conducting aluminum-doped zinc oxide (AZO) films with different film thickness had been prepared on soda-lime glass substrates by radio frequency magnetron sputtering using a high density ceramic target. The structural, morphology, electrical, and optical properties of the AZO thin films were investigated by X-ray diffraction, scanning electron microscope, Hall-effect measurement and optical transmission spectroscopy, which were strongly influenced by film thickness. With the film thickness increasing from 140 nm to 710 nm, the resistivity decreases from 9.78 × 103 to 3.23 × 103 Ω.cm and an average optical transmission decreases from 88% to 80% in the visible range and the optical bandgap decreases from 3.47 to 3.24 eV.

The curriculum construction is a very important work leading to the excellent course. Welded Structure (including 40 class hours) is one of main and compulsory course for the major of Material Molding and Control Engineering in our university. It is very important and necessary to construct the course in time. Based on the project of High Quality Curriculum Construction for Welded Structure undertaken by the authors, this paper makes a discussion on the original ideas, goals and contents, strategies and measures of the project. Meanwhile, the course construction and reform of Welded Structure are introduced from following aspects, such as curriculum setting, teaching contents and methods, teaching staffs, teaching quality management and supervision, online teaching resource construction. The purpose of the paper is to provide beneficial references and experiences to facilitate the further curriculum construction and reform in higher school.

Ba0.6Sr0.4TiO3 (BST) thin films were fabricated by solgel technique on Pt/Ti/SiO2/Si substrate without and with PbO seeding layer from precursor solutions with different concentrations. The crystal structure, surface morphology, dielectric properties and leakage current density of BST thin films are investigated as functions of the concentration of PbO precursor solution. Its found that the growth orientation of BST thin films with PbO seeding layer can be modulated through adjusting the concentration of PbO precursor solution. BST thin film with PbO seeding layer from 0.05 M precursor solution shows the highest dielectric constant and tunability, which may be attributed to the high crystallization and amplitude of the polarization in high (100) preferred orientated films. The leakage current density of BST films increases with the increasing concentration of PbO precursor solution and agrees well with the space-charge-limited current mechanism at room temperature.

A steady thermal conduction model was presented to study the temperature field and thermal stress distribution in film irradiated by continuous wave laser. The thermal effects may arise from either the absorbing inclusions or the intrinsic absorption of film. Based on the plane thermal conduction assumption, the characteristics of damage resulted from local melting or evaporation and thermal stress were discussed. The damage region resulted from local melting or evaporation smaller than that from thermal stress. The circumferential stress σθ is the main cause accounting for the stress damage. The normal stress perpendicular to the interface between film and substrate is the direct cause of drum type damage. The characteristics of damage in unsteady thermal conduction caused by pulse laser can be analyzed qualitatively by means of this model.

The thermal transportation caused by absorbing inclusions in optical films under the radiation of laser pulse is unsteady heat conduction. The temperature distribution in films is ununiform and time-dependent. Considering the small size of inclusions, the absorbing inclusions were treaded as dot-heat sources. Based on this assumption, the unsteady heat conduction model was brought out and the temperature distribution in films was figured out and discussed, the mechanism that the catastrophic damage may avoid with micro-damage or micro-deformation in films through the release of stress concentration is presented. By comparing the thermal effects caused respectively by single inclusion and assembling ones, the effect of inclusion size on thermal damage in films was discussed.

Pb0.3Sr0.7TiO3 (PST) thin films have been prepared from precursor solution sonicated for different time on Pt/Ti/SiO2/Si substrates by sol-gel method. The effect of ultrasonic processing on the chemical bonding of PST precursor solution and the thermal evolution of PST dry gel are characterized with FT-IR and TG-DT technology. The structure, dielectric properties and leakage current density of PST thin films are investigated as functions of sol ultrasonic processing time. It’s found that ultrasonic processing brings about the partial sol structure rearrangement, the delay of PST formative temperature, the reduction of crystallization and dielectric constant, and the significant improvement of leakage current, dielectric loss and the figure of merit (FOM). The results suggest that the enhancement in the quality of thin films prepared with sol-gel method can be obtained by the suitable ultrasonic processing on precursor solutions. The PST thin film prepared from precursor solution sonicated for 8 h shows the highest FOM for its appropriate tunability of 57.36% and low dielectric loss of 0.0144.

Bismuth zinc niobate titanium (Bi1.5Zn0.5 Nb0.5Ti1.5O7) (BZNT) thin films were deposited on PtTiSiO2Si substrates by radio frequency (rf) magnetron sputtering. The microstructure, surface morphology, stress, dielectric and tunable properties of thin films were investigated as a function of initial annealing temperature. It’s found that high initial annealing temperature increases the grain size, dielectric constant and tunability of BZNT films simultaneously and decreases the tensile stress in films. The BZNT thin film annealed from 500 ℃ to 700 ℃ shows the highest FOM value of 45.67 with the smallest dielectric loss and upper tunability.

BZNT (Bi1.5Zn0.5Nb0.5Ti1.5O7) thin films were prepared on Pt/Ti/SiO2/Si substrates by radio frequency (RF) magnetron sputtering in different O2/Ar ranging from 4:16 to 7:13. The structure and surface morphology of BZNT thin films were investigated by x-ray diffraction (XRD) and atom force microscopy (AFM). The analysis of component in BZNT films were carried out by x-ray photoelectron spectroscopy (XPS). The dielectric measurements were conducted on metal-insulator-metal capacitors at the frequency from 100 Hz to 1M Hz. It’s found that the O2/Ar ratios significantly influence the elements content in BZNT thin films and the morphology and dielectric properties of BZNT thin films. At 1M Hz, the dielectric constant of BZNT thin films deposited at O2/Ar ranging from 4:16 to 7:13 is 212, 187, 171, 196, respectively. The BZNT thin film prepared at O2/Ar = 6:14 shows the highest figure of merit for its very low dielectric loss of 0.0024.

Based on the surface morphology, a model is presented to investigate the heat transfer in anodic aluminum oxide (AAO) porous thin films. The extra thermal resistance from the micropores will inevitably cause a change in thermal properties, which can be analyzed by the Fourier law. The effect of the characteristic size on the thermal conductivity is discussed in details by means of the theory of phenomenological model of phonon scattering. Considering the effects of porosity and the distribution of micropores reflected by parameter D, the function of the effective thermal conductivity of AAO porous thin films expressed by two independent variables, εp and D. The temperature field is simulated with the effective thermal conductivity and the result demonstrates a bigger temperature rise in AAO porous thin films.

Transparent conducting aluminum-doped zinc oxide (AZO) films have been prepared on soda-lime glass substrates by radio frequency magnetron sputtering using a high density ceramic target at different substrate temperatures. The structural, morphology, electrical, and optical properties of the AZO thin films were investigated by X-ray diffraction, scanning electron microscope, Hall measurement, and optical transmission spectroscopy, and which were strongly influenced by substrate temperatures. Films with better texture, higher transmission, lower resistivity and larger carrier concentration were obtained for the samples fabricated at higher substrate temperature. The AZO film with the lowest resistivity of 4.63×10−4 Ω.cm and an average optical transmission of 92% in the visible range was deposited on the substrate heated at 450 °C. The optical bandgap depends on the deposition condition, and was in the range of 3.35~3.59 eV.

Tai chi (TC) is proposed as a potential option for the management of osteoarthritis (OA), however, its beneficial effect on patients with knee OA has not been convincing.

Under the protection of argon gas, carbon nanotube reinforced magnesium metal matrix composite was made by stirring carbon nanotube into magnesium melts and formed by die casting. TEM and EDS methods were introduced to analyze boundary structure and chemical composition between carbon nanotube and magnesium metal matrix. The mechanical carbon nanotube properties of the composite were tested. Nickel chemical plating surface of carbon nanotube is favorable to adhesion of carbon nanotube to magnesium. Tests show that carbon nanotube, especially chemical nickel-plated one, has excellent role in strengthening the magnesium. The structure of magnesium was fined .The tensile strength, elongation, hardness and elastic modulus of the composite are improved.