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The Czochralski method was used to grow a 46-mm-long crystal of the Ba8Ga16Ge30 clathrate, which was cut into disks that were evaluated for thermoelectric performance. The Seebeck coefficient and electrical and thermal conductivities all showed evidence of a transition from extrinsic to intrinsic behavior in the range of 600–900K. The corresponding figure of merit (ZT) was found to be a record high of 1.35 at 900K and with an extrapolated maximum of 1.63 at 1100K. This makes the Ba8Ga16Ge30 clathrate an exceptionally strong candidate for medium and high-temperature thermoelectric applications.

Copper hexacyanoferrate, Cu(II)[Fe(III)(CN)6]2/3·nH2O, was synthesized, and varied amounts of K(+) ions were inserted via reduction by K2S2O3 (aq). Ideally, the reaction can be written as Cu(II)[Fe(III)(CN)6]2/3·nH2O + 2x/3K(+) + 2x/3e(-) ↔ K2x/3Cu(II)[Fe(II)xFe(III)1-x(CN)6]2/3·nH2O. Infrared, Raman, and Mössbauer spectroscopy studies show that Fe(III) is continuously reduced to Fe(II) with increasing x, accompanied by a decrease of the a-axis of the cubic Fm3̅m unit cell. Elemental analysis of K by inductively coupled plasma shows that the insertion only begins when a significant fraction, ∼20% of the Fe(III), has already been reduced. Thermogravimetric analysis shows a fast exchange of water with ambient atmosphere and a total weight loss of ∼26 wt % upon heating to 180 °C, above which the structure starts to decompose. The crystal structures of Cu(II)[Fe(III)(CN)6]2/3·nH2O and K2/3Cu[Fe(CN)6]2/3·nH2O were refined using synchrotron X-ray powder diffraction data. In both, one-third of the Fe(CN)6 groups are vacant, and the octahedron around Cu(II) is completed by water molecules. In the two structures, difference Fourier maps reveal three additional zeolitic water sites (8c, 32f, and 48g) in the center of the cavities formed by the -Cu-N-C-Fe- framework. The K-containing compound shows an increased electron density at two of these sites (32f and 48g), indicating them to be the preferred positions for the K(+) ions.

Our results indicate that ECG-gated CT has comparable diagnostic performance to TEE and may be a valuable complement in the preoperative evaluation of patients with aortic PVE.

No abstract

For Abstract see ChemInform Abstract in Full Text.

The influence of nitrogen (N) fertilizer application rate (0 vs. 70 vs. 140 kg N ha–1) and timing (early = at sowing vs. late = at sowing and before heading) on the amount of protein groups, amount and size distribution of mono‐ and polymeric proteins, and gluten strength was investigated in one set of wheat cultivars (Triticum aestivum L.). Due to their genetic background, the cultivars had different protein concentrations and gluten strengths. Despite this, all of them reacted similarly on rate and timing of nitrogen application. The rate of nitrogen fertilizer increased the variation in protein concentration, gluten strength, and also the variation in most of the investigated protein components. Higher nitrogen fertilizer rate increased protein concentration, decreased gluten strength, and increased the total amount of glutenins and gliadins as well as the amounts of most mono‐ and polymeric proteins. Timing of fertilizer did not influence protein concentration. The gluten strength and the relations of proteins were changed by the timing of fertilizer. Early nitrogen feritilizer applications led to higher gluten strength and a higher percentage of total unextractable polymeric protein in the total polymeric protein and large unextractable polymeric protein in the total large polymeric protein, compared to late nitrogen fertilizer applications.

Weather variations in Sweden result in differences in the bread-making quality of wheat. This study investigated whether the variation in bread-making quality caused by yearly weather fluctuations could be explained by variation in protein composition, amount of storage proteins, protein subunits and protein groups, and relative amount and size distribution of polymeric proteins. Four spring wheat (Triticum aestivum L) cultivars grown in Sweden during three different years were investigated. Bread-making quality and gluten strength were measured using baking and glutograph tests. SDS-PAGE, SE-HPLC, RP-HPLC and ELISA were applied for investigation of protein composition, amount of storage proteins, protein subunits and protein groups, and relative amount and size distribution of polymeric proteins. The bread volume within cultivars varied depending on the cultivation year. The highest gluten strength was found in 1994 and the weakest in 1991. Variation in composition or relative amount of specific storage proteins, protein subunits or protein groups could not explain the variation in gluten strength between years. Instead, a significant relationship was found between the cultivation year and the percentage of unextractable polymeric protein in the total polymeric protein. The percentage of unextractable polymeric protein in the total polymeric protein was found to be highest during years when gluten strength was also high.