High‐Pressure Synthesis of A2NiO2Ag2Se2 (A=Sr,Ba) with a High‐Spin Ni2+ in Square‐Planar Coordination

Square‐planar coordinate Ni²⁺ ions in oxides are exclusively limited to a low‐spin state (S=0) owing to extensive crystal field splitting. Layered oxychalcogenides A₂Ni^IIO₂Ag₂Se₂ (A=Sr, Ba) with the S=1 NiO₂ square lattice are now reported. The structural analysis revealed that the Ni²⁺ ion is under‐bonded by a significant tensile strain from neighboring Ag₂Se₂ layers, leading to the reduction in crystal field splitting. Ba₂NiO₂Ag₂Se₂ exhibits a G‐type spin order at 130 K, indicating fairly strong in‐plane interactions. The high‐pressure synthesis employed here possibly assists the expansion of NiO₂ square lattice by taking the advantage of the difference in compressibility in oxide and selenide layers.     

Simple and inexpensive method for cryopreservation of fish sperm combining straw and powdered dry ice

Here, we propose a simple and inexpensive method for fish sperm cryopreservation. Sperm samples of the loach Misgurnus anguillicaudatus (Teleostei: Cobitidae) were diluted 7-fold by an extender containing 63.5 mM NaCl, 114 mM KCl, 20 mM Tris and 10% methanol. The cryogenic straws were placed in three kinds of self-made tubes which diameter was changed by commercially available materials and then immersed into powdered dry ice for 2 min and plunged into liquid nitrogen. This procedure resulted in a cooling rate at -421.4 +/- 119.84 (control), -55.8 +/- 4.32 (tube 1), -40.2 +/- 3.43 (tube 2) and -33.3 +/- 2.09 C/min (tube 3). In the slowest cooling rate by the tube 3, total motility (72 +/- 3 %), duration (146 +/- 12 s) and hatching rates (29 +/- 04 %) were higher than those by other rates. Progressive motility (83 +/- 5 %) did not differ significantly from fresh samples.     

Molecular beam epitaxy of GaSb on ZnTe/GaAs: Influence of the chemical composition of ZnTe surface

We have studied the molecular beam epitaxy (MBE) of GaSb films on GaAs (0 0 1) substrates by using ZnTe as a new buffer layer. GaSb films were grown on two distinct ZnTe surfaces and the influence of surface chemical composition of ZnTe on the morphological and structural properties of GaSb films has been investigated. Initial 2-dimensional (2D) growth of GaSb films is obtained on Zn-terminated surface consequently smooth morphology and high crystal quality GaSb films are achieved. The thin GaSb film (0.4 μm) grown on Zn-terminated ZnTe surface reveals considerably narrow X-ray diffraction linewidth (113 arcsec) along with small residual strain, which strongly supports the availability of ZnTe buffer for the growth of high-quality GaSb film.     

Simultaneous determination of erlotinib and its isomeric major metabolites in human plasma using isocratic liquid chromatography–tandem mass spectrometry and its clinical application

This study developed a method for the simultaneous determination of erlotinib and its isomeric major metabolites, OSI‐413 and OSI‐420, in human plasma using an isocratic liquid chromatography–tandem mass spectrometry. Plasma specimens deproteinized with acetonitrile were separated using a 3‐µm particle size octadecylsilyl column. The m/z values of the precursor and product ions for the analytes were as follows: erlotinib, 394.2/278.2; and OSI‐413 and OSI‐420, 380.2/278.2. The total run time was 21 min and no peaks interfering with the analytes and internal standard (d₆‐erlotinib) in human plasma were observed. The calibration curves of erlotinib, OSI‐413 and OSI‐420 were linear over the concentration ranges of 10–3000, 2–500 and 2–100 ng/mL, respectively. The pretreatment recovery ratios were >86.1%. The intra‐ and inter‐assay precisions and accuracies were <12.7 and 89.0–108.9% for all analytes. This validated method was applied to the determination of plasma samples in lung cancer patients receiving 150 mg of oral erlotinib. The plasma concentration ranges of erlotinib, OSI‐413 and OSI‐420 were 373–2354, 15.7–379 and 2.5–43.6 ng/mL, respectively. In conclusion, the present method can be helpful for evaluating the plasma exposures of erlotinib and its major isomeric metabolites in clinical settings. Copyright © 2014 John Wiley & Sons, Ltd.     

Relativistic Lagrangians for the Lorentz–Dirac equation

We present two types of relativistic Lagrangians for the Lorentz–Dirac equation written in terms of an arbitrary world-line parameter. One of the Lagrangians contains an exponential damping function of the proper time and explicitly depends on the world-line parameter. Another Lagrangian includes additional cross-terms consisting of auxiliary dynamical variables and does not depend explicitly on the world-line parameter. We demonstrate that both the Lagrangians actually yield the Lorentz–Dirac equation with a source-like term.     

Synthesis and dynamic structure of multinuclear Rh complexes of porphyrinoids

Large porphyrinoids with three Rh(CO)2 groups at their dipyrrin units shows two-step metal transposition through the macrocycle in solution and the equilibrium between the C3v-isomer and the Cs-isomer depends on the solvent polarity.     

Highly soluble [1]benzothieno[3,2-b]benzothiophene (BTBT) derivatives for high-performance, solution-processed organic field-effect transistors

2,7-Dialkyl[1]benzothieno[3,2-b]benzothiophenes were tested as solution-processible molecular semiconductors. Thin films of the organic semiconductors deposited on Si/SiO2 substrates by spin coating have well-ordered structures as confirmed by XRD analysis. Evaluations of the devices under ambient conditions showed typical p-channel FET responses with the field-effect mobility higher than 1.0 cm2 V-1 s-1 and Ion/Ioff of approximately 10(7).