Structure-property relations of co-doped bismuth layer-structured Bi3.25La0.75(Ti1-xMox)3O12 ceramics

In this work, the fabrication and investigation of substituting higher-valence Mo6+ for Ti4+ ion on the B-site of La3+-doped Bi4Ti3O12 [BLT] structure to form Bi3.25La0.75(Ti1-xMox)3O12 [BLTM] (when x = 0, 0.01, 0.03, 0.05 0.07, 0.09, and 0.10) ceramics were carried out. X-ray diffraction patterns of BLTM ceramics indicated an orthorhombic structure with lattice distortion, especially with a higher concentration of a MoO3 dopant. Microstructural investigation showed that all ceramics composed mainly of plate-like grains. An increase in MoO3 doping content increased the length and thickness of the grain but reduced the density of the ceramics. Electrical conductivity was found to decrease, while the dielectric constant increased with Mo6+ doping concentration. Ferroelectric properties were found to be improved with increasing MoO3 content and were optimized at x = 0.1

Crystal structure and electrical properties of bismuth sodium titanate zirconate ceramics

Lead-free bismuth sodium titanate zirconate (Bi0.5Na0.5Ti1-xZrxO3 where x = 0.20, 0.35, 0.40, 0.45, 0.60, and 0.80 mole fraction) [BNTZ] ceramics were successfully prepared using the conventional mixed-oxide method. The samples were sintered for 2 h at temperatures lower than 1,000°C. The density of the BNTZ samples was at least 95% of the theoretical values. The scanning electron microscopy micrographs showed that small grains were embedded between large grains, causing a relatively wide grain size distribution. The density and grain size increased with increasing Zr concentration. A peak shift in X-ray diffraction patterns as well as the disappearance of several hkl reflections indicated some significant crystal-structure changes in these materials. Preliminary crystal-structure analysis indicated the existence of phase transition from a rhombohedral to an orthorhombic structure. The dielectric and ferroelectric properties were also found to correlate well with the observed phase transition

Effects of frequency on electrical fatigue behavior of ZnO-modified Pb(Mg1/3Nb2/3)0.65Ti0.35O3 ceramics

This work aims to study the effects of frequency on the electrical fatigue behavior of ZnO-modified Pb(Mg1/3Nb2/3)0.65Ti0.35O3 (PMNT) ceramics. Changes in microstructures, ferroelectric and piezoelectric properties of the ceramics at bipolar electrical fatigue frequencies of 5, 10, 50 and 100 Hz were observed. The thickness of damaged surface of the ceramics decreased with increasing frequency. The degradation of properties of the ceramics fatigued at low frequency was greater than those fatigued at high frequency. The degradation by electrical fatigue at lower frequencies, 5 and 10 Hz, could be caused by the effects of both field screening and domain pinning, while at higher frequencies the fatigue was mainly a result of the field screening effect. The fatigue properties of ZnO-modified PMNT ceramics was compared to Pb-based and Pb-free ferroelectric ceramics. It was found that the fatigue endurance of ZnO-modified PMNT ceramic was greater than that of hard PZT ceramic but less than that of Pb-free ferroelectric ceramic

Effect of thermal spray processes on microstructures and properties of Ni-20%Cr coatings

Ni-20%Cr coatings were produced using different thermal spray techniques, which were spray and fuse, flame spray and arc spray. The Ni-20%Cr powder was sprayed onto a mild steel substrate using the spray and fuse and the flame spray systems, while the Ni-20%Cr wire was sprayed using the arc spray system. SEM microstructures of the coatings suggested the spraying conditions used were able to produce dense microstructures. However, the microstructure of the arc sprayed coatings showed fine lamellar characteristics compared to the coatings prepared by the spray and fuse and the flame spray techniques. Chemical elements and oxide were quantified by EDS-SEM technique. Differences in microstructure and coating characteristics such as content of porosity and oxide due to different processing techniques significantly affected the coating properties such as adhesion strength, hardness and wear rate

ELECTRICAL AND MECHANICAL PROPERTIES OF PZT/PVDF 0–3 COMPOSITES

Granules of in-house prepared PZT ceramic and powder of commercially available PVDF polymer were used as starting materials to form a series of xPZT/(1 - x)PVDF composites (where x = 0, 0.1, 0.3, 0.5, 0.7, 0.9, and 1.0) with 0–3 connectivity. Densities of the composites tended to increase with increasing PZT ceramic content. Phase and microstructure of the composites revealed homogeneous mixture between PZT and PVDF phases. The composites with higher ceramic content had higher dielectric constant and dielectric loss tangent. Ferroelectric measurement revealed the effect of PZT phase connectivity in 0.9PZT/0.1PVDF ceramic in which a sudden jump in ferroelectric properties was observed. Mechanical properties in terms of hardness, Young's modulus and fracture toughness were also improved when PZT content was increased.PZT/PVDF, composite, 0–3 connectivity, electrical properties, mechanical properties

Bortezomib-encapsulated dual responsive copolymeric nanoparticles for gallbladder cancer targeted therapy

Gallbladder cancer (GBC) is a rare but the most malignant type of biliary tract tumor. It is usually diagnosed at an advanced stage and conventional treatments are unsatisfactory. As a proteasome inhibitor, bortezomib (BTZ) exhibits excellent antitumor ability in GBC. However, the long-term treatment efficacy is limited by its resistance, poor stability, and high toxicity. Herein, BTZ-encapsulated pH-responsive copolymeric nanoparticles with estrone (ES-NP(BTZ; Ce6) ) for GBC-specific targeted therapy is reported. Due to the high estrogen receptor expression in GBC, ES-NP(BTZ; Ce6) can rapidly enter the cells and accumulate near the nucleus via ES-mediated endocytosis. Under acidic tumor microenvironment (TME) and 808 nm laser irradiation, BTZ is released and ROS is generated by Ce6 to destroy the "bounce-back" response pathway proteins, such as DDI2 and p97, which can effectively inhibit proteasomes and increase apoptosis. Compared to the traditional treatment using BTZ monotherapy, ES-NP(BTZ; Ce6) can significantly impede disease progression at lower BTZ concentrations and improve its resistance. Moreover, ES-NP(BTZ; Ce6) demonstrates similar antitumor abilities in patient-derived xenograft animal models and five other types of solid tumor cells, revealing its potential as a broad-spectrum antitumor formulation.Published versionM.C., S.J., S.L., and W.T. contributed equally to this work. This work was supported by the National Natural Science Foundation of China (NO. 81827804 and 81800540), Zhejiang Provincial Natural Science Foundation of China (NO. LQ22H160003), Zhejiang Clinical Research Center of Minimally Invasive Diagnosis and Treatment of Abdominal Diseases (NO. 2018E50003), and Key Research and Development Project of Zhejiang Province (NO. 2018C03083)