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The perovskite manganese oxide, La 0.7 Sr 0.3 Mn 1+ x O 3 (x = −0.4, −0.2, 0, 0.2, 0.4, 0.6, 0.8, 1.0), was synthesized using the solid-state reaction method. A single-phase perovskite structure was obtained at the stoichiometric composition (x = 0). However, with an increase in Mn excess (x > 0), secondary phases of Mn 2 O 3 and Mn 3 O 4 formed and increased, while La 2 O 3 and Sr-rich phases emerged when Mn is deficient (x < 0). The electrical conductivity, permittivity, and permeability of the samples showed significant variations with x , as both charge transport and magnetism originate from the presence of Mn. Complex permittivity (ε', ε") and permeability (μ', μ") spectra were utilized to calculate RL maps based on a transmission line theory. For samples with x ≥ 0, which exhibited relatively high values of ε' and ε", there was no significant absorption of electromagnetic (EM) waves within the measured frequency range (0.1 ≤ f ≤ 18 GHz) due to high EM wave reflection. Conversely, the Mn-deficient samples (x = −0.2, −0.4) demonstrated excellent EM wave absorption properties in the GHz range. This can be attributed to their favorable impedance matching characteristics, resulting from significantly reduced ε' and ε" values in the Mn-deficient samples. Notably, the sample with x = −0.2 exhibited the most outstanding EM wave absorption characteristics, with an RL value of −56 dB at a frequency of 2.33 GHz and a thickness of 7.59 mm. Additionally, it achieved an RL value of −50 dB at 9.8 GHz and 2.90 mm thickness. [ABSTRACT FROM AUTHOR]

In this study, the effects of natural water components (nitrate, carbonate/bicarbonate, and humic acid) on the kinetics and degradation mechanisms of bisphenol A (BPA) during UV-C photolysis and UV/H 2 O 2 reaction were examined. The presence of NO 3 − (0.04–0.4 mM) and CO 3 2− /HCO 3 − (0.4–4 mM) ions increased BPA degradation during UV photolysis. Humic acid less than 3 mg/L promoted BPA degradation, but greater than 3 mg/L of humic acid inhibited BPA degradation. During the UV/H 2 O 2 reaction, all water matrix components acted as radical scavengers in the order of humic acid > CO 3 2− /HCO 3 −  > NO 3 − . All of the degradation reactions agreed with the pseudo-first-order kinetics. While eight byproducts ( m / z  = 122, 136, 139, 164, 181, 244, 273, 289) were identified in UV-C/NO 3 − photolysis reaction, four ( m / z  = 122, 136, 164, 244) and three byproducts ( m / z  = 122, 136, 164) were observed during UV-C/NO 3 − /CO 3 2− /HCO 3 − and UV-C/CO 3 2− /HCO 3 − reactions. Nitrogenated and hydrogenated byproducts were first observed during the UV-C/NO 3 − photolysis, but only hydrogenated byproducts as adducts were detected during the UV-C/NO 3 − /CO 3 2− /HCO 3 − photolysis. Nitrogenated and hydrogenated byproducts were formed in the early stage of degradation by OH or NO 2 radicals, and these byproducts were subsequently degraded into smaller compounds with further reaction during UV-C/NO 3 − and UV-C/NO 3 − /CO 3 2− /HCO 3 − reactions. In contrast, BPA was directly degraded into smaller compounds by β-scission of the isopropyl group by CO 3 − /HCO 3 radicals during UV-C/CO 3 2− /HCO 3 − reaction. Our results imply that the water components can change the degradation mechanism of BPA during UV photolysis. [ABSTRACT FROM AUTHOR]

Magnetic soft-hard composites of perovskite La-Sr manganite (LSMO) and M-type Sr-hexaferrite (SrM), LSMO(1 − x )–SrM( x ) with x  = 0, 0.05, 0.1, 0.3, 0.5, and 1.0 were prepared by solid-state reaction. Although the two phases coexist without forming secondary phases, the saturation magnetization ( M S ) value of the LSMO phase decreased with the doping of SrM ( x  ≥ 0.05). Clear double hysteresis behaviors were observed in the samples with x  = 0.3 and 0.5, while single soft magnetic hysteresis was noted in the samples with x  ≤ 0.1. In the M-T measurement, the composite with x  = 0.5 exhibited a diffusive temperature dependence of magnetization unlike that of non-doped LSMO ( x  = 0). Weakening of ferromagnetism in the composites can be attributed to interatomic diffusion between the two phases occurring during calcination at 1200 °C. [ABSTRACT FROM AUTHOR]

Ca-Co-Mn-Zn-doped Sr-hexaferrites with a cation composition of Sr 0.7 Ca 0.3 Fe n-0.6 Co 0.2 Mn 0.2 Zn 0.2 were prepared using conventional solid-state reaction processes by varying Fe contents (10 ≤ n ≤ 17). The hexaferrite sample with an Fe content of 10 ≤ n ≤ 13 exhibited composite phases of M-type and W-type hexaferrite on calcining at 1250 °C in air while the samples calcined at 1200 °C in air exhibited only the M-type phase. The sample with n = 13 exhibited a saturation magnetization ( M S ) of 70.7, 75.3, 78.0 emu/g after performing calcination at 1200, 1250, and 1300 °C, respectively. M S higher than that of the non-doped M-type Sr-hexaferrite (~ 72 emu/g) sample is attributed to the volume portion of the high- M S W-type phase. It is also revealed that the co-doping of Ca, Co, and Zn is crucial for the formation of the W-type phase in the sample calcined at 1250 °C in air. [ABSTRACT FROM AUTHOR]

Two different magnetic hysteresis behaviors with and without exchange coupling between magnetic hard M-type Sr-hexaferrite (SrM) and soft perovskite La-Sr manganite (LSMO) could be achieved by controlling the synthesis process routes of the solid-state reaction. Double hysteresis curves without exchange coupling were observed in the composite prepared by calcinations of the mixture of LSMO and SrM powders, while exchange-coupled single hysteresis behavior was obtained in the composite synthesized directly from the initial precursor powders. The possible origins of the difference in the magnetic coupling behavior between the two composites were discussed. [ABSTRACT FROM AUTHOR]

The crystalline phases, microstructure, and magnetic properties of Ca-Mn-Zn-substituted M-type Sr-hexaferrites have been investigated with respect to the doping level of Ca, and various additives. Ca-Mn-Zn-substituted M-type Sr-hexaferrites, Sr 1- x Ca x Fe 11.8 Mn 0.1 Zn 0.1 O 19 (0 ≤ x ≤ 1.0) were synthesized by solid-state reaction. The solubility limit of Ca into the M phase, x , was found to be ∼0.5. The maximum saturation magnetization of 74.9 emu/g could be obtained at x = 0.3 (Sr 0.7 Ca 0.3 Fe 11.8 Mn 0.1 Zn 0.1 O 19 ), which is higher than that of non-substituted SrFe 12 O 19 by 3.2%. For the optimal composition of the calcined powder, Sr 0.7 Ca 0.3 Fe 11.8 Mn 0.1 Zn 0.1 O 19 , sintering processes were performed with various kinds of additives including SiO 2 , Mn 3 O 4 , ZnO, Co 3 O 4 , Al 2 O 3 , La 2 O 3 , and SrCO 3 . The better hard magnetic performances in the sintered samples of Sr 0.7 Ca 0.3 Fe 11.8 Mn 0.1 Zn 0.1 O 19 could be achieved than in the non-substituted SrFe 12 O 19 when the kind and amount of sintering additives were effectively controlled. [ABSTRACT FROM AUTHOR]

Ce–Mn substituted M-type Sr-hexaferrites (SrM) of Sr 1− x Ce x Fe 11− x Mn x O 19 and Sr 1− x Ce x Fe 11−2 x Mn 2 x O 19 (0≤ x ≤0.2) were synthesized by solid-state reaction routes. Ce–Mn doped SrM exhibited an increased coercivity ( H C ) of ~5 kOe, which is 37% higher than that of non-substituted SrM ( x =0). This high H C could be obtained without reducing the saturation magnetization ( M S ) when the optimally doped ( x =0.1) powder samples were calcined at 1200 °C. The Ce–Mn doped SrM samples also showed enhanced thermal stability of H C , characterized by ~60% lower temperature coefficient for H C compared to the undoped SrM. The increased H C and the higher thermal stability of H C are attributable to both the grain refinement and the enhancement of magneto-crystalline anisotropy in the Ce–Mn SrM. [ABSTRACT FROM AUTHOR]

La–Ce–Zn-doped M-type Sr-hexaferries Sr 0.7 La 0.3− x Ce x Fe 11.7 Zn 0.3 O 19− d (0≤ x ≤0.3) were synthesized by solid-state reaction in both air and nitrogen atmospheres. The increased saturation magnetization of ~78 emu/g, which is ~5% higher than that of La–Zn-doped Sr-hexaferrite (Sr 0.7 La 0.3 Fe 11.7 Zn 0.3 O 19 ), could be obtained when the Ce-doped powder samples ( x ≥0.1) were either annealed in nitrogen at 1100 °C after calcination in air at 1200 °C or directly calcined in nitrogen at 1200 °C. The increased M S over the practical limit (~74 emu/g) is attributable to both the formation of magnetic composites with high- M S spinel phases and the M S increase of the M-type hexaferrite itself caused by oxygen vacancies. [ABSTRACT FROM AUTHOR]

Highlights: [•] Isoflavones differed significantly with cultivars, crop years, and seed coat colours. [•] Malonylgenistin and cyanidin-3-O-glucoside had the most remarkable variations. [•] Protein, oil, and fatty acid showed slight variations in coloured seed coat soybeans. [•] The acidified methanol extracts of soybeans exhibited potent antioxidant properties. [•] Antioxidant activities are correlated with isoflavone and anthocyanin contents. [Copyright &y& Elsevier]

Abstract: Proteins expressed by the brown-rot fungus Gloeophyllum trabeum were characterized from inoculated southern yellow pine sapwood undergoing decay, from pure cultures of the fungus and from uninoculated pinewood. Analysis was carried out by two-dimensional polyacrylamide gel electrophoresis and MALDI-TOF/TOF/MS. No proteins were detected from the clean uncontaminated wood. The inoculated wood undergoing active brown-rot decay produced 76 proteins, including the Fenton-chemistry related enzymes, alcohol oxidase, lipoxygenase, and catalase. One hundred and eleven proteins were detected from the pure culture and most were common metabolic proteins. A majority of proteins in both samples were identified as hypothetical proteins. A surprising result is that there was very little overlap between proteins found in both sets of samples, indicating a very different mechanism in action when the fungus is growing on a cellulose-based nutrient source (wood) versus glucose media. This study also highlights a current limitation of this approach, which is the limited protein and genomic sequence information annotated on the public databases. Of the 187 proteins characterized, only 36 were identified with confidence. To our knowledge, this is the first reported proteomic analysis of pinewood decayed by a brown-rot fungus and provides the initial characterization of proteins involved in this type of wood biodeterioration. Although significant limitations still exist in identifying the proteins, this limitation will diminish as functional proteins are identified and added to the databases. [Copyright &y& Elsevier]

• The magnetic properties of Zn-substituted Z-type Sr-hexaferrites were investigated. • The Z-type hexaferrites-epoxy composites exhibited GHz-range EM wave absorber performances. • The EM absorption properties can be modulated by the Zn substitution. Zn-substituted Z-type Sr hexaferrites (Sr 3 Co 2− x Zn x Fe 24 O 41 , x = 0, 0.5, 1.0, 1.5) were prepared by solid-state reaction routes. The magnetic and high-frequency properties of the sintered bodies and powder–epoxy composites were studied. Almost-single-phase Z-type hexaferrite could be obtained in the sample calcined at 1160 °C and then sintered at 1210 °C. Double hysteresis behaviors were observed for the Z-type hexaferrites with x = 1.0 and 0.5. Gradual shifts of the μ' and μ ″ spectra to lower frequencies accompanied with gradual increases in their intensities were observed with the increase in the Zn substitution content x , owing to the decrease in the magnetocrystalline anisotropy. Complex permeability and permittivity measurements of the Z-type hexaferrite–epoxy composites were performed using a network analyzer. The composites exhibited magnetodielectric properties with low loss factors (μ ″ and ε ″ ≈ 0) under 1 GHz and good electromagnetic wave absorption performances up to several gigahertz. [ABSTRACT FROM AUTHOR]

High-dielectric constant (κ) materials have been extensively investigated for several potential applications, particularly in low-voltage-operating organic field-effect transistors (OFETs). To ensure the operational stability of the OFET, the interface between the organic semiconductor and the high- κ dielectric should be fully controlled. In the current work, we overcoated a fluorinated polymer, namely poly(pentafluorostyrene) (PFS), onto one of the high- κ materials, namely barium titanate (BaTiO 3), and used this bilayer to fabricate highly stable OFETs. The surfaces of the BaTiO 3 dielectric layers were effectively modified with the PFS overcoating. Compared to the uncoated BaTiO 3 , the PFS/BaTiO 3 bilayer dielectric showed significantly reduced leakage current and altered surface properties. The smoothness of the surfaces of the PFS/BaTiO 3 films appeared to have been responsible for the observed improved crystal structures of the overlying pentacene molecules. In addition, the surface dipoles and electron-withdrawing character of the PFS/BaTiO 3 films built a high hole injection barrier between the semiconductor and dielectric layers, with this barrier blocking hole trapping. Finally, overcoating BaTiO 3 with PFS allowed the resulting PFS/BaTiO 3 to be utilized as a gate dielectric layer for highly stable OFETs during low-voltage operation. These OFETs exhibited hysteresis-free transistor performances and reliable operation under a sustained gate-bias stress in air. • Fluorinated polymer was overcoated on high- κ BaTiO 3 dielectric film. • Overcoating of the fluorinated polymer allowed BaTiO 3 film to exhibit good surface morphologies, insulating properties. • The OFETs prepared with fluorinated polymer/BaTiO 3 dielectric film improved reliable performances under gate-bias stress. [ABSTRACT FROM AUTHOR]

The effects of additives Bi 2 O 3 and MnCO 3 on the structural and magnetic properties of M-type Sr-hexaferrites (SrFe 12 O 19 ) prepared by a conventional solid-state reaction method were studied. The saturation magnetization value of undoped SrFe 12 O 19 is 71.8 emu/g; it increases to 72.6 emu/g and 74.2 emu/g with Bi 2 O 3 doping of 0.5 wt%and 1.0 wt%, respectively. However, abnormal grain growth occurs and the coercivity (H C ) decreases significantly in the 1 wt% Bi 2 O 3 -doped sample. Co-doping of 0.5 wt% Bi 2 O 3  + 0.5 wt% MnCO 3 is effective, because a higher saturation magnetization (73.1 emu/g) than that of undoped SrFe 12 O 19 could be achieved with a relatively large coercivity of ∼3.3 kOe. Based on the lattice parameter calculation, Bi 3+ preferably substitutes into Fe 3+ sites rather than Sr 2+ sites in M-type Sr-hexaferrite. The enhanced saturation magnetization can be attributed to the selective substitution of nonmagnetic Bi 3+ into the down-spin Fe 3+ site (4 f 1 or 4 f 2 ). [ABSTRACT FROM AUTHOR]

The effects of methyl jasmonate (MJ) and salicylic acid (SA) on the production of tropane alkaloids (TA) and the expression of putrescine N-methyltransferase (PMT) and hyoscyamine 6β-hydroxylase (H6H) were studied in adventitious root cultures of Scopolia parviflora. MJ treatments increased the amounts of both scopolamine and hyoscyamine, with growth inhibition of the roots, while SA increased the amount of scopolamine without negative effects on growth. Regarding both MJ and SA, their concentrations and exposure times were factors that strongly affected the production of TA. Western blot analysis showed that treatments with MJ or SA regulated the expression of the key enzymes PMT and H6H and the biosynthesis of TA. The results from this study suggest that MJ and SA regulated directly or indirectly the expression of PMT or the H6H gene and, finally, increased the production of TA and stimulated the excretion of TA into the culture medium. [Copyright &y& Elsevier]

In an attempt to increase productivity, the effect of elicitation on tropane alkaloids (TA) biosynthesis was studied in adventitious hairy root cultures of Scopolia parviflora. Two Gram-positive strains and one Gram-negative strain of bacteria were used as biotic elicitors. The raw bacterial elicitors affected the tropane alkaloid profile by increasing the scopolamine concentration, while the autoclaved bacterial elicitors produced similar effects on the control. The conversion ratio of hyoscyamine to scopolamine was increased following elicitation using raw bacterial elicitors. The bacterial elicitor inhibited the expression of H6H (hyoscyamine 6β-hydoxylase) whereas the expression of PMT (putrescine N-methyltransferase) was raised by elicitation. These results have important implications for the large-scale production of tropane alkaloids. [Copyright &y& Elsevier]

The Ca-La-Co-doped M-type Sr-hexaferrite (Sr 0.1 Ca 0.45 La 0.45 Fe 11.7 Co 0.3 O 19 ) decomposed into three different phases of orthorhombic, spinel, and hexagonal structures after annealing at 1200 °C in nitrogen atmosphere while the non-substituted SrFe 12 O 19 maintained the hexagonal structure after annealing at the same condition. It is suggested that the charge-imbalance substitution of La 3+ /Co 2+ = 1.5 induces phase instability of the M-type structure and it causes the phase transformation during the N 2 annealing. In film experiment, polycrystalline Sr-hexaferrite films (SrFe 12 O 19 ) have been prepared by pulsed laser deposition and post-annealing processes. When the film was annealed in vacuum at 500 °C, the magnetization value at the magnetic field H = 15 kOe increased by ∼80% and the coercivity decreased significantly without microstructural change. [ABSTRACT FROM AUTHOR]

Abstract: The mass production of tropane alkaloids from adventitious root cultures of Scopolia parviflora, in small-scale bubble column bioreactor (BCB) was attempted. Adventitious roots of S. parviflora produced relatively enhanced levels of scopolamine and hyoscyamine in bioreactor compared to flask type cultures, and rapidly produced root clumps, with continuously increasing biomass throughout the culture period. The production of scopolamine and hyoscyamine in the top and bottom regions of root clumps were higher than in the core region. The adventitious root cultures of S. parviflora in the BCB required a relatively high level of aeration. The optimized conditions for the bioreactor culture growth and alkaloid production were found to be 3g of inoculum, on a fresh weight basis, a 15-day culture period and 0.4vvm of airflow. The elicitation by Staphylococus aureus increased the specific compound of scopolamine, while the production of hyoscyamine was slightly inhibited in BCB cultures. [Copyright &y& Elsevier]