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High temperature lead-free piezoelectric ceramics 0.67BiFeO3–0.33BaTiO3 doped with 0.35 mol% MnO2 and xBiScO3 (x = 0, 0.005, 0.01, 0.015, 0.02) were prepared by conventional solid-state sintering method. The effects of BiScO3 doping on the crystal structure, piezoelectric, ferroelectric and dielectric properties of BiFeO3-BaTiO3 piezoelectric ceramics were investigated. The results show that the BiScO3 doping can not change the crystal structure of the ceramics and the grain size of ceramics increases first and then decreases with the BiScO3 doping content increasing. The optimum piezoelectric properties d33 = 165 pC/N, kp = 0.349 and Qm = 52.132 were obtained when x = 0.01, with the highest remanent polarization Pr = 37.1 μC/cm2. The ceramics become normal ferroelectrics determined by temperature spectrum with the increase of x, and the Curie temperature and depolarization temperature of 425 and 408 °C are respectively obtained when x = 0.01. In particular, a small amount of BiScO3 doping is beneficial to the improvement of the temperature stability. Moreover, a perovskite solid solution forms between the BiScO3 and BiFeO3-BaTiO3 ceramics, which can improve the electrical properties of BF-BT ceramic system.

Anodization is a widely used method to obtain multicoloured oxidized titanium sheets. However, most researchers paid great attention to the colour-related properties instead of photoelectrical properties of titanium oxide film obtained by anodization. In this work, to study their photoelectrical properties, a series of multicoloured oxidized titanium sheets were prepared by anodization method, and UV–vis absorption and photocurrents were tested. The relationship between anodization voltages/anodization durations and photocurrents of titanium sheets was studied. Results show that titanium sheets have excellent photoelectrical performance. With the increase of anodization voltage, the number of UV–vis absorption peaks increased under visible light which means increasing absorption. When anodization duration increased, absorption band edge also increased in the visible light region, which means the band gap needed to produce charge transfer transition decreased. Under simulated sunlight and applied voltage of +0.4 V, photocurrent increased with the increase of either anodization voltage or anodization duration, and can be expressed by linear equations. In addition, anodization currents were recorded during anodization. Morphology, crystal structure and photoelectrical properties of anodized titanium sheets were characterized. The anodized titanium sheets can not only be used as decorative material in jewellery and architecture fields etc. but also are supposed to be used as photoelectrical catalyst in further work.

Eg can be calculated by the equation: Eg (eV) = 1240 / λg. However, the method to determinate λg value is not uniform in different literatures. In this paper, we used the mostly common method to determinate the value of λg , namely the intersection point of the curve tangent to the ultraviolet absorption long wave direction and the baseline. With the values of λg in Figure 4, we calculated Eg values which were listed in Tables 1. From Table 1, it can be seen that the value of Eg has no obvious relation to anodization voltage while anodization duration was kept at 10 min.;Eg can be calculated by the equation: Eg (eV) = 1240 / λg. However, the method to determinate λg value is not uniform in different literatures. In this paper, we used the mostly common method to determinate the value of λg , namely the intersection point of the curve tangent to the ultraviolet absorption long wave direction and the baseline. With the values of λg in Figure 5, we calculated Eg values which were listed in Tables 2. From Table 2 it can be seen that the value of Eg decrease with the increase of anodization duration while voltage was kept at 100 V. It means less energy is needed to create the charge transfer transition.

CTE mismatch between direct bonding copper (DBC) layers results in excessive thermal stress, causing the fatigue cracks and delamination after long time run, which deteriorate the reliability of DBC and the power module in the end. A method of designing mesh patterns on DBC is proposed in this paper to release the thermal stress. At the same time, the comprehensive analysis of the relationship between the mesh patterns and the DBC reliability is made. The finite element method is used to simulate the distributions and variations of thermal stress on DBC with different mesh patterns. Both the theoretical and experimental results prove the function of the thermal stress release for the mesh on DBC. Furthermore, the meshes on the edge or corner, and with smaller size are most effective. In experiment, compared with the DBC without mesh, the thermal cycling lifetime for the DBC with the optimized mesh pattern could be improved by 15 times.

Heat-stable antifungal factor (HSAF), which was first isolated from Lysobacter enzymogenes, exhibits inhibitory activities against a wide range of pathogens; however, a low level of HSAF was obtained from L. enzymogenes cultured in 0.1 × tryptic soy broth (TSB), an amount that does not satisfy HSAF application in disease control. In this study, the optimization of media components and environmental conditions were examined for improving the production of HSAF from L. enzymogenes OH11. The one factor at a time method was used to screen optimal nitrogen and carbon sources and inorganic salt. Then the orthogonal matrix method was used to determine the optimal concentration of the media components and environmental factors. The results showed that the maximum level of HSAF (23361 mAU·s) was achieved when OH11 cultured in the media of 0.7% (w/v) soybean powder, 0.5% (w/v) glucose and 0.08% CaCl2 at 200 rpm at 30°C for 60 h, which is much higher than that cultured in 0.1 × TSB. This opens up the possibility of HSAF or L. enzymogenes utilization for biological control of plant disease.

This study aims to assess the association of the preoperative neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) with tumor stage in colorectal cancer (CRC) patients. A retrospective study was performed in 336 CRC patients. Preoperative whole blood counts, serum levels of carcinoembryonic antigen (CEA), and clinicopathologic data were collected. The correlations between laboratory parameters and the tumor, node, and metastasis (TNM) stages were analyzed. The clinicopathologic TNM stages among CRC patients were 12.8 % at stage I, 32.4 % at stage II, 44.6 % at stage III, and 10.1 % at stage IV. NLR, PLR, and CEA levels were higher in CRC patients compared to healthy controls (all P

Thymidine kinase 1 in serum (STK1) has been found to be a reliable proliferation marker in clinical trials. In this study, we examined the significance of STK1 in routine clinical settings.The concentration of STK1 was determined by a sensitive dot blot ECL assay. The STK1 value was correlated to clinical stage and reactions and used for monitoring the outcome of surgery and/or multidrug chemotherapy of 1,247 patients with five different types of carcinomas (lung, esophagus, gastric, head and neck, and thyroid) in routine clinical settings.The STK1 values correlated with the clinical stage in patients with lung, esophagus, thyroid, and gastric carcinomas. After treatment, STK1 declined in all tumor groups after treatments (P0.01). The STK1 was low (2 pM) or decreasing during treatment in patients with clinical reactions of complete response (CR) or partial response (PR), but high (2 pM) or increasing in patients with stable disease (SD) or progressive disease (PD), some of them showing metastasis. STK1 also reflected the differences in clinical reactions when surgery and chemotherapy were compared.We concluded that the concentration of TK1 in serum correlates to clinical stages and clinical reactions and monitors the effect of tumor therapies, not only in controlled clinical trials, but also in routine clinical settings.