Localization and magnetism of Fe replacing either Mn or Ni in the Ni2Mn1.44Sn0.56-type Heusler alloy have been systematically investigated using magnetization, scanning electron microscopy and Mössbauer spectroscopy. It has been shown that the addition of Fe either in Mn or in Ni sites reduces the fraction of the Mn-rich NiMnSn-type Heusler alloys that has short-range antiferromagnetic interactions; consequently it reduces the martensitic–austenitic transition temperature and increases the thermal hysteresis width due to an increase in atomic disorder caused by Fe replacements. The Fe atoms in Mn sites have two magnetic configurations with magnetic moments of 0.8μB/Fe and 1.4μB/Fe in the martensitic orthorhombic structure, while Fe in Ni sites have magnetic moments smaller than 0.1μB/Fe. These results indicate that the Fe atoms are distinctly substituting either Mn or Ni and the decrease in the martensitic phase transition temperature for increasing Fe content can be mainly attributed to the Fe atoms in the Mn sites in both cases.

The present study reports a physicochemical comparison of shade-grown and sun-grown coffee beans, under unripe, rip and roasted-ripe conditions, using electrical conductivity measurements, electron paramagnetic resonance (EPR), infrared spectroscopy (FTIR), and high performance liquid chromatography (HPLC). Moreover, the assessed physicochemical parameters were compared with organoleptic evaluations based on the Coffee Quality Institute protocol. The values found for electrical conductivity, leached potassium, and stable free radicals were respectively 29%, 31%, and 350% higher for shade-grown coffee beans, whereas polyphenol oxidase enzymatic activity was 23% lower. By contrast, FTIR and HPLC measurements identified higher chlorogenic acid and lipid contents in sun-grown coffee beans. Importantly, the sensorial grade attributed to roasted-ripe grains was 12% higher for sun-grown coffee. Our findings suggest that shade-grown coffee beans have undergone microorganismal activity and undesired fermentation during cultivation, which resulted in lower coffee quality. A correlation between a set of selected physicochemical properties and organoleptic properties was robustly

Magnetic nanosheets can be easily synthesized without the use of templates by adding glycerol as an intermediate for the nanosheets production.

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This study reports on physicochemical properties (total soluble solids, titratable acidity plus caffeine, trigonelline, 5-CQA, and total phenols contents) of five genotypes of Robusta coffee beans; Bamburral, Beira Rio, Clementino, Coringa, and Pirata. Green bean of Clementino presents the highest concentration of total soluble solids in dry basis (18.0%) and the lowest titratable acidity (154.0 mL-NaOH). Moreover, green beans of Clementino and Pirata show intermediate values of caffeine and trigonelline contents while presenting the highest yield index ofstable free radical formation after roasting, respectively equal to 26 and 23 (electron paramagnetic resonance-EPR data), and the highest content of 5-CQA (around 42 mg/g). Green beans of Bamburral, Beira Rio and Coringa show the highest concentration of total phenols (53 -56 mg/g), meaning the highest antioxidant activities (IC50 test) but reduced yield index of formation of stable free radicals after roasting, respectively equal to 13.0, 5.9, and 13.0 (EPR data).