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International audience; Employing the new nitronyl nitroxide biradical ligand biNIT-3Py-5-Ph (2-(5-phenyl-3-pyridyl)bis(4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide)), a 16-spin Cu-radical complex, [Cu 8 (biNIT-3Py-5-Ph) 4 (hfac) 16 ] 1, and three 2p-3d-4f chain complexes, {[Ln(hfac) 3 ][Cu(hfac) 2 ] 2 (biNIT-3Py-5-Ph) 2 } n (Ln III = Gd 2, Tb 3, Dy 4; hfac = hexafluoroacetylacetonate), have been prepared and characterized. X-ray crystallographic analysis revealed in all derivatives a common cyclic [Cu-biNIT] 2 secondary building unit in which two bi-NIT-3Py-5-Ph biradical ligands and two Cu II ions are associated via the pyridine N atoms and NO units. For complex 1, two such units assemble with four additional Cu II ions to form a discrete complex involving 16 S = 1/2 spin centers. For complexes 2-4, the [Cu-biNIT] 2 units are linked by Ln III ions via NO groups in a 1D coordination polymer. Magnetic studies show that the coordination of the aminoxyl groups with Cu or Ln ions results in behaviors combining ferromagnetic and antiferromagnetic interactions. No slow magnetic relaxation behavior was observed for Tb and Dy derivatives.

A series of In2O3/Au nanorods (NRs) were fabricated and characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X–ray diffractometer (XRD) and X–ray photoelectron spectroscopy (XPS). The length to diameter ratios of In2O3/Au NRs was periodically modulated in the range of 2.9–4.5 through controlling the initial content of indium salt and reaction time. Their gas sensing properties to volatile organic compounds (VOCs) were carefully studied and then applied in exhaled breath detection. The results demonstrate that In2O3/Au NRs gas sensor can effectively detect acetone at 250 °C and ethanol at 400 °C. The corresponding actual detection limit is as low as 0.1 ppm to acetone and 0.05 ppm to ethanol, respectively. Moreover, by using humidity compensation method, In2O3/Au NRs gas sensor can clearly distinguish the acetone and ethanol biomarkers in human breath. The main reason of the enhanced gas sensing properties was attributed to the “spillover effects” between Au and In2O3 NRs. The excellent sensing performance indicates that In2O3/Au NRs is a promising functional material to actual application in monitoring and detecting diabetes and safe driving area in a noninvasive and more accurate way.

Based on analysis of basic photonic Doppler velocimetry (PDV), a formula to measure velocity variation in a single cycle is put forward. PDV has been improved in three aspects, namely, the laser, the detector and the data processing. A measurement system for velocity of the initial stage of a shock motion has been demonstrated. Instantaneous velocity measurements have been performed. The experimental results have a good agreement with the values obtained from the accelerometer. Compared with the traditional fringe method, the proposed method in this paper can identify instantaneous velocity variation. So it is particularly suitable for measuring the velocity in the transient acceleration process of shock waves and detonation waves.

Alloy 718 has a very long history, it is still used extensively, which accounts for more than 50% of commercial superalloy productions in the world. The reason is that Alloy 718 exhibits good strength, excellent weldability and lastly, but most importantly, reasonable cost. Recently, confocal scanning laser microscope (CSLM) offers a convenient way for conducting a real-time and continuous in-situ observation of phase transformations at high temperatures. Several studies using CSLM have been reported for low carbon steel, stainless steel and metallic glass materials. The aim of this paper is to study the solidification behavior of Alloy 718 using confocal scanning laser microscope. In addition to the in-situ observation of solidification at different cooling rates, the analysis of microstructure evolution was conducted by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The results show that the cooling rate has a great impact on the solidification behavior of Alloy 718. Variation of secondary dendrite arm spacing, morphology change in MC carbide, and Laves phase after solidification at different cooling rates are studied in details. Introduction Alloy 718 is an age-hardenable wrought superalloy used for elevated temperature gas-turbine applications, which is famous for its excellent balance of properties and reasonable cost, accounting for more than 50% of commercial superalloy productions in the world [1]. With the development of land-based power generation and aircraft propulsion, scaling-up of components has become the necessity. In response to market demands the size of Alloy 718 ingot produced by VIM-ESR-VAR triple melting has increased markedly over the past 10 years [2-7]. However, the solutes segregation problem, mainly niobium segregation, is a big issue for producing large size Alloy 718 ingots. Particularly, some macrosegregations such as freckles and white spots formed during the solidification process may lead to failure of entire ingot. Therefore the indepth studies of solidification behavior of Alloy 718 are still needed.

Fully leaky optical-guided mode was employed to determine the difference in the splay and bend flexoelectric coefficient (e1–e3) in negative nematic liquid crystal MS-N01300-000. The experimental curves of reflectivity versus internal angle (angle of incident light to the liquid crystal) were obtained when a laser beam passed through the hybrid-aligned nematic in-plane switching liquid crystal cell; the cell was embedded in pyramid-coupled waveguide with different alternating current (AC) and direct current (DC) voltages. The curves of the applied DC with voltage similar to that of AC shift to the left or the right. Experimental results were then compared with theoretical results derived from elastic continuum theory and multi-layer optical theory of liquid crystals. The approximate value of the flexoelectric coefficient (e1–e3) of MS-N01300-000 is 9.0 × 10−11 C/m.

Diastereomeric dipeptides were derived from the amino acid enantiomers in dentin by O-phthalaldehyde-N-acetyl-L-cysteine. The products were separated using high performance liquid chromatography (HPLC) and detected by fluorescence detector. A short analysis time (total analysis time was 15 min, including retention time, sample derivatization time and column regeneration time) was used. The sensitivity of detection was 1 pmol and high resolution (Rs = 1.5) was reached. We determined the D/L ratio of aspartic acid in dentin of 28 first premolars. The correlation value between the D/L ratio of aspartic acid and actual age was 0.9887; errors of +/- 1 year accounted for 46.4%, and no error exceeded 5 years.

Sixty Chinese skulls (30 males and 30 females) from Liaoning Province of the People's Republic of China were used in this study. Forty-one variables on each skull were measured and one group of 14 and a second group of 5 variables were selected from all the variables by applying multiple stepwise regression on a computer. Discriminant equations for the 14 and 5 variables for sex diagnosis have been obtained and these variables are highly significant. The discriminant rate for the group of 5 variables resulted in accurate sex determination in 96.7% of cases. For the group of 14 variables there was 100% success rate.