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Background The prognosis of patients with primary lymphoma of the central nervous system (PCNSL) is poor, and identifying the prognostic predictors is the key to improving their prognosis. Biopsychosocial models suggest the important prognostic value of psychosocial factors, but the association of marital status, one important psychosocial factor, with the prognosis of PNSCL patients remains unclear. Objective To assess the association of marital status with the overall survival (OS) and cancer-specific survival (CSS) in patients with PCNSL. Methods The data of 3 993 patients diagnosed with PCNSL between 2000 and 2016 were extracted from the Surveillance, Epidemiology and End Results database in 2020, including sociodemographics〔marital status (married, or single containing unmarried, divorced or widowed) , age of diagnosis, year of diagnosis, ethnicity, gender〕, clinicopathological features (pathological type and location of the PCNSL) , treatment (surgery, radiotherapy and chemotherapy) and outcome data (survival and follow-up time) . The propensity score matching (PSM) was used to balance the baseline variables of the married and singles. The Log-rank test was used to compare the Kaplan-Meier curves of OS and CSS by marital status. Cox regression was used to identify the association of marital status with OS and CSS. Results After PSM, there were no significant differences in baseline variables between married and single patients (P>0.05) . The Log-rank test demonstrated that single patients had worse OS and CSS than the married (P

In this work, ZnO–Bi2O3 based low-voltage varistors were prepared by co-doping of In2O3 and Ta2O5, which achieved a high nonlinear coefficient with a low breakdown voltage. By exploring the microstructure and electrical performance of the samples, it was found that the samples co-doped with In2O3 and Ta2O5 have uniform microstructure, and the threshold voltage decreased slightly while the leakage current decreased. The best performance of the varistor was obtained at 0.15 mol% Ta2O5 doping with a breakdown voltage of 184 V/mm, a nonlinear coefficient of 32.3 and a leakage current of 0.04 μA. The grain boundary resistance of the varistor increased after the co-doping of In2O3 and Ta2O5, which was conducive to improving performance stability of the sample. All varistors could be aged, but the parameter change rate of doped varistors was significantly smaller. [ABSTRACT FROM AUTHOR]

The crystal phase combination, relative density, microstructure, varistor properties and dielectric properties of La2O3-doped ZnO-Bi2O3-based varistor at a furnace temperature of 950 °C were investigated under the electric field of 300 V/cm within 35 s. Obtained samples were fully densified and uniform in microstructure. The effect of doping with different contents of La2O3 on flash-sintered ZnO-Bi2O3-based varistor was systematically studied. The results showed that when doping La2O3 was 0 mol%, 0.1 mol%, 0.2 mol% and 0.3 mol%, the densities of the samples were 91.5%, 90.5%, 96.1% and 95.1%, respectively. When the La2O3 doping amount was 0.2 mol%, the nonlinear coefficient was the highest of 32.9, the leakage current was the lowest of 1.1μA, and the dielectric loss was less than 0.1. Therefore, uniform microstructure and excellent electrical property can be obtained by preparing La2O3-doped ZnO varistor ceramic via flash sintering. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to study the effects of MnO2 on the ZnO–Bi2O3-based varistor prepared via flash sintering (FS) Design/methodology/approach: MnO2-doped ZnO–Bi2O3-based varistors were successfully prepared by the FS with a step-wise increase of the.current in 60 s at the furnace temperature <750°C under the direct current electric field of 300 V cm−1. The FS process, microstructure and the electrical performance of ZnO–Bi2O3-based varistors were systematically investigated. Findings: The doping of MnO2 significantly decreased the onset temperature of FS and improved the electrical performance of FS ZnO varistor ceramic. The sample with 0.5 mol% MnO2 doping shows the highest improvement, with the nonlinear coefficient of 18, the leakage current of 16.82 µA, the threshold voltage of 459 V/mm and the dielectric constant of 1,221 at 1 kHz. Originality/value: FS is a wonderful technology to enhance ZnO varistors for its low energy consumption, and a short sintering time can reduce grain growth and inhabit Bi2O3 volatilize, yet few research studies work on that. In this research, the authors analyzed the FS process and improved the electrical characteristics through MnO2 doping. [ABSTRACT FROM AUTHOR]

The continuous development of microelectronic devices with integrated functions has led to an increasing interest in the development of dielectric ceramics with high dielectric constant, low dielectric loss, good frequency, and temperature stability. In this work, (Ca, Sb)-co-doped TiO2 (CSTO) ceramics were prepared by solid-phase reaction sintering method and their phase structure, microstructure, giant dielectric properties, and mechanism were systematically investigated. The results show that the secondary phase of CSTO ceramic samples appeared when x ≥ 4%. The average grain size of CSTO ceramics decreased as the amount of doping increases, and all CSTO ceramics had giant dielectric constants. When the doping amount was x = 4%, the CSTO ceramics obtained optimum dielectric properties, where ε′ = 2.6 × 105 and tan δ = 0.10. X-ray photoelectron spectroscopy (XPS) results showed that the giant dielectric origin was mainly due to the Sb5+ doping that generated electrons inside the material, Ca2+ doping that enhanced the generation of vacancies inside the material, and the defective dipole clusters produced that improved the dielectric properties of the CSTO ceramics. This work is critical for the development and deployment of new TiO2-based giant dielectric ceramics. [ABSTRACT FROM AUTHOR]

The dense bulk ZnO–Bi2O3–Co2O3 varistor ceramics were obtained via flash sintering. The effect of electric field on densification, microstructure, and electrical properties of ZnO–Bi2O3-based varistor ceramics, which were under different electric fields by a constant heating flash sintering process was investigated. The results showed that when the electric field was increased from 200 to 350 V/cm, the onset temperature of flash sintering decreased significantly, and the peak power consumption increased. The flash-sintered specimen under the electric field of 200 V/cm at a furnace temperature of 762 °C obtained the highest nonlinear coefficient of 41.1 and the lowest leakage current of 1.57 μA. [ABSTRACT FROM AUTHOR]

In this paper, (Al, Ta) co-doped TiO2 (ATTO) ceramics were successfully prepared by flash sintering method under different electric fields (450–650 V/cm). The effects of electric field on flash sintering behavior, phase structure, microstructure, dielectric properties and varistor properties of ATTO ceramics were systematically studied. The results showed that all flash sintering ATTO ceramics were single rutile structure. With increasing electric field, grain size gradually increased. When the electric field was 550 V/cm, ATTO ceramic had the best comprehensive performance with dielectric constant of approximately 1.7 × 104, dielectric loss of about 0.5 at 1 kHz, and nonlinear coefficient of 3.5. X-ray photoelectron spectroscopy (XPS) and Impedance spectra (IS) results showed that the origin of good dielectric property was attributed to the internal barrier layer capacitance effect. Therefore, this work is not only of great significance to the further study of co-doped TiO2 colossal dielectric ceramics, but also offers an excellent method for the preparation of capacitive varistor dual-function ceramics. [ABSTRACT FROM AUTHOR]