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A new hybrid material was created by blending sodium titanate ceramics (Na2Ti3O7/Na2Ti6O13) with a polyvinyl alcohol (PVA) matrix, resulting in enhanced semiconductive characteristics. The synthesis process involved intense ultrasonic treatment and subsequent heat treatment at 900 °C. Utilizing a solvent casting method, Na2Ti3O7/Na2Ti6O13/PVA composites were fabricated. Raman spectra confirmed the presence of PVA chains and distinctive bands of sodium titanates. Elemental analysis verified the existence of Na and Ti in both composites. Morphological observations revealed the formation of irregular agglomerates upon introducing sodium titanates into the PVA structure, leading to a rise in the average surface roughness (Ra) from ~ 1.5 to 7.9 nm post-incorporation of heated Na2Ti3O7/Na2Ti6O13. Differences in morphology between samples loaded with unheated and heated Na2Ti3O7/Na2Ti6O13 suggested a more effective particle incorporation into the polymeric matrix after heat treatment. Electrical measurements indicated that the composite loaded with unheated Na2Ti3O7/Na2Ti6O13 exhibited the lowest electrical resistance (105 Ω) and a relaxation time of 3.16 × 10− 5 s. These results demonstrate that the inclusion of sodium titanate ceramics enhances the semiconductive properties of the PVA matrix. This finding highlights the potential of this material for various electronic applications, including components for solid-state batteries. [ABSTRACT FROM AUTHOR]

Isolates from the Fusarium fujikuroi species complex, mainly F. sacchari, have been reported to be the causal agents of pokkah boeng in sugarcane in Brazil. However, inadequate information was available on the occurrence and genetic diversity of F. sacchari in Northeast Brazil, which is a limiting factor on management. Thus, isolates of F. subglutinans sensu lato from sugarcane plants with symptoms of pokkah boeng were evaluated using the sexual cross‐fertility to determine species. All the isolates produced black perithecia when they were crossed with the test isolates of F. sacchari. Three weeks after the crossing, the formation of fertile ascospores cirri was observed. Thirty‐four isolates were self‐sterile hermaphrodites, while 21 were fertile only as males. Five isolates were homothallic. The effective size [Ne(f)] of the population as a function of the frequency of hermaphrodites and female sterile strains was 95.5%. The F. sacchari isolates were separated into four genetic groups independent of geographic location. The mean of polymorphism among all populations was 79%, and the average unbiased genetic diversity (uh) was considered moderate (0.31). This study in addition to confirming that F. sacchari as the main species associated with pokkah boeng in sugarcane in Northeast Brazil, reveals the relationship of mating type and genetic diversity of F. sacchari. The unrestricted gene flow between regions is probably the best explanation for the low geographic correlation. This knowledge will help in the adoption of management measures with fungicides or resistant cultivars. [ABSTRACT FROM AUTHOR]

Poly(o -methoxyanilines) (POMA) were chemically synthesized using different dopant acids to obtain the polymers POMA/HCl, POMA/HNO 3 , POMA/H 2 SO 4 and POMA/H 3 PO 4. The nature and size of the counterions influenced considerably on the structural, morphological, thermal and electrical properties of the as-synthesized polymers. X-ray Diffraction (XRD) patterns presented slightly peak displacements according to the dopant acid, influencing the lattice parameters specially along [010]. The polymers POMA/HCl, POMA/HNO 3 and POMA/H 2 SO 4 presented similar percentage of crystallinity (around 50%), while the polymer POMA/H 3 PO 4 presented de lower crystallinity (around 40%). Polymer morphology was dependent on the dopant acid, besides multimorphologies were observed in the polymers POMA/HCl, POMA/HNO 3 and POMA/H 3 PO 4. A great counterion influence from the doping acid was found in the electrical properties of the material. The total variation obtained in DC conductivity was five orders of magnitude. The calculated values were 6.6 × 10−1 S/cm, 1.11 × 10−2 S/cm, 3.64 × 10−3 S/cm, 5.2 × 10−4 S/cm for POMA/HCl, POMA/HNO 3 , POMA/H 2 SO 4 and POMA/H 3 PO 4 , respectively. The use of HCl as a dopant potentiated the DC conductivity of the polymeric material. Image 1005 • X-ray Diffraction patterns presented peak displacements according to the dopant acid. • Polymer morphology was dependent on the dopant acid. • Crystallites reached a maximum average size. • Electrical conductivity of POMA/H 3 PO 4 was dependent on the frequency. • The use of HCl potentiated the DC conductivity of the polymeric material. [ABSTRACT FROM AUTHOR]