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The effects of ball milling and subsequent annealing on the negative thermal expansion (NTE) properties of β-Cu1.8Zn0.2V2O7 were investigated. The NTE of β-Cu1.8Zn0.2V2O7 is generated by microstructural effects distinct to the ceramic body. Ball milling produces β-Cu1.8Zn0.2V2O7 particles about 1 μm in size, but the process degrades its NTE characteristics. Results show that subsequent annealing restores the NTE properties. By annealing at 500 °C, the absolute value of the negative coefficient of thermal expansion becomes greater than the crystallographic value, which indicates that the microstructures of β-Cu1.8Zn0.2V2O7 are not completely destroyed by ball milling. Ball milling used in combination with subsequent annealing may produce NTE β-Cu1.8Zn0.2V2O7 fine particles suitable for the control of thermal expansion in local regions.

We conducted magnetization measurements on an S = 3 / 2 “breathing” pyrochlore antiferromagnet LiInCr4O8 in magnetic fields of up to 130 T using a coaxial-type magnetization pickup coil in a horizontal single-turn coil megagauss generator. The magnetization process exhibits a phase transition to a 1/2-magnetization plateau phase accompanied by a sudden increase in the magnetization with a discernible hysteresis at approximately 100 T. In addition, we also observed a shoulder-like behavior in the magnetization process prior to the 1/2-plateau phase, implicating the existence of a novel magnetic phase, peculiar to the “breathing” pyrochlore antiferromagnet.

A strategy to improve the thermoelectric properties of LaCoO3 by the double substitution of Sr and Mg in La1−xSrxCo1−xMgxO3 (x=0, 0.025, 0.05, 0.1) is presented. Effects of either Sr or Mg substitution are also investigated separately in the series of La1−xSrxCoO3 and LaCo1−xMgxO3 (x=0, 0.02, 0.05, 0.1, 0.2). All the samples were successfully synthesized by the citrate sol–gel method. Replacing La by a small amount of Sr increases electronic conductivity but decreases the Seebeck coefficient; the decrease in the Seebeck coefficient is reduced when Mg is simultaneously substituted for Co. The employment of both Sr and Mg substitutions benefit to the enhancement in thermoelectric efficiency since both electrical conductivity and Seebeck coefficient are enhanced while thermal conductivity is suppressed. With this strategy, a sample with a small amount of double substitution, which is typically La0.975Sr0.025Co0.0975Mg0.025O3, exhibits a ZT of 0.047 at room temperature.

Extracranial injury of the hypoglossal nerve and the recurrent laryngeal nerve is known as Tapia's syndrome, which is an extremely rare complication associated with general anaesthesia. We report a case of Tapia's syndrome occurring after orthognathic surgery. A 34-year-old man underwent 2 jaw-orthognathic surgery under general anaesthesia, which consisted of bilateral sagittal split ramus osteotomy, Le Fort I osteotomy and genioplasty. After surgery, the patient complained of hoarseness and some difficulty in swallowing the liquid diet. Four days after surgery when the intermaxillary fixation was removed, the deviation of the tongue to the left side on protrusion was found. The consultation to an otolaryngologist about his hoarseness revealed the left vocal cord paralysis. Finally, the patient was diagnosed as the palsies of the left hypoglossal nerve and left recurrent laryngeal nerve, that is Tapia's syndrome. The lingual and laryngeal functions were recovered 3 months after surgery.

Vortex pinning in the β-pyrochlore oxide superconductor KOs 2 O 6 with T c = 9.6 K is investigated by measuring magnetic torque. A large anisotropy of magnetic torque is observed in the superconducting state below T p = 7.6 K, where a first-order structural transition takes place, in spite of the inherent isotropic nature of the structural and electronic properties. Magnetic torque is enhanced at external magnetic fields parallel to the [1 1 1] and [0 0 1] directions. Moreover, a pronounced peak effect is also observed in the magnetic field dependence of the torque in these two directions. We consider that the observed anisotropy is related to a microstructure associated with the structural transition.

The growth mechanism of ultrathin palladium films deposited on Ni(111) at 300 K was studied by scanning tunneling microscopy (STM) in ultrahigh vacuum. It was revealed that nearly ideal two-dimensional palladium films grow on Ni(111) up to the first three layers. Wide-area STM images clarified that palladium islands grow initially from the step edges of the substrate, indicating the existence of a significant barrier for diffusion across the step edges. Hexagonal moire superstructures were clearly observed in the overlayer images. The periodicity of the moire patterns was determined to be 33±3 A, which corresponds to 12 palladium atoms and 13 nickel atoms. Based on the STM images, a structure model for the palladium overlayer on Ni(111) is proposed.

The total-reflection grazing-incidence technique has been applied to measure the S K-edge soft X-ray absorption fine structure spectra of submonolayer thiophene on Pd(111) and Pd(100) surfaces. The total-reflection mode allows us to obtain reliable spectra with a much higher signal-to-background ratio compared to that given by the conventional non-total reflection method. Similar surface structures of adsorbed thiophene are consequently determined on both surfaces. Thiophene molecules are found to lie flat accompanied by slightly elongated S–C bonds due to the charge transfer of 1.1–1.2 electrons from the Pd valence bands to the thiophene π* orbital. The S atom in the thiophene adsorbate is located at an intermediate position between bridge and atop sites. The displacement is estimated to be 0.61±0.05 A away from the bridge site towards the atop one. The structural and electronic properties of adsorbed thiophene on Pd(111) and Pd(100) are discussed in comparison with the previous results on Ni(100) and Cu(100).

(Z)-2-(2-aminothiazol-4-yl)-N-(2-hydroxyethyl)-2-(hydroxyimino)acetamide (HL) has been employed as a model compound for an orally active cephalosporin antibiotic, Cefdinir (CFDN). A binuclear copper(II) complex Cu2L4 (1) has been obtained from an aqueous solution containing CuCl2 and HL, and its structure determined by means of X-ray crystallography: monoclinic, P2/c, a = 11.954(3) A, b = 10.661(3) A, c = 16.969(7) A, β = 108.13(3)°, Z = 2. The molecular structure of 1 is a dimeric copper(II) complex consisting of two copper(II) complex units CuL2, where the two molecules of L (La and Lb) are coordinated to the copper atom through their thiazole and oximate nitrogen atoms. La is also coordinated to the copper atom of the other CuL2 unit through the oximate oxygen atom, namely, the two complex units are bound to each other by forming a pair of oximate NO bridges of the two La molecules. The coordination environment of the copper atom is a distorted trigonal bipyramid. In addition, based on the molecular structure, the coordination property of CFDN to copper(II) in water has been clarified by means of spectrophotometry and titration. Both copper(II) (0.05 mM)-HL (0.1 mM) and copper(II) (0.05 mM)-CFDN (0.1 mM) aqueous solutions gave broad d-d bands at ca. 720 nm above pH 6, corresponding to that observed in the diffuse reflectance spectrum of the crystals of 1. The results indicate that CFDN also forms a binuclear copper(II) complex, Cu2(CFDN)4, corresponding to Cu2L4 as the main species in water above pH 7. Stability constants are as follows: log β110 = 11.12, log β240 = 41.13 for copper(II)-L complexes. The theoretical species distribution diagram as a function of pH for the copper(II) (0.05 mM)-HL (0.1 mM) system shows that Cu2L4 exists as the main species above pH 7. The titration results are consistent with the spectral data. The spectral and titration studies indicate that not only HL, but also CFDN forms a binuclear complex Cu2(CFDN)4 corresponding to Cu2L4 as the main species under the neutral and basic conditions. In addition, the stability constants of CFDN complexes should be as large as those of CuL complexes, although titrations for copper(II)-CFDN systems could not be carried out due to precipitation of copper(II)-CFDN complexes.

The validation of the HPLC method used for the determination of cefdinir and its related substances is described. The developed method was specific and stability-indicating and provided a linear response with concentration. The system and method precision, expressed as relative standard deviations, were not greater than 1%, and the reproducibilities within and between laboratories were acceptable for the assay method. The procedure can quantitate related substances greater than approximately 0.05% of the principal cefdinir peak.

Cefixime (CX), an oral cephalosporin antibiotic, and its metabolites in human digestive organs were separated by various modes of high-performance capillary electrophoresis. The zone electrophoresis mode in phosphate buffer (pH 6.8) containing 3-[(3-cholamidopropyl)dimethylammonio]-1-propanesulphonate gave the best separation, permitting the complete resolution of CX and all of five metabolites. On the other hand, the plain zone electrophoresis mode in phosphate buffer (pH 6.8) offered a simple procedure for the direct determination of urinary CX concentration using intact urine samples.

Structural characterization of two polymorphs (Forms A and B) of 8-(2-methoxycarbonylamino-6-methylbenzyloxy)-2-methyl-3-(2-p ropynyl)-imidazo [1,2-a]pyridine (1) was accomplished by X-ray crystallographic analysis. Form A crystallized in the monoclinic space group C2/c, with a = 42.936 (14), b = 4.356 (1), c = 21.536 (6) A, beta = 109.92 (4) degrees, z = 8, and dcal = 1.275 g/cm3. Form B crystallized in the monoclinic space group P2(1)/c, with a = 4.367 (1), b = 38.214 (3), c = 11.253 (1) A, beta = 95.47 (2) degrees, z = 4, and dcal = 1.292 g/cm3. Some subtle conformational differences between the polymorphs were observed. Although the Form B crystal has a somewhat more compactly packed structure than Form A, this compactness is thought to be disadvantageous to conformational features and to the crystal structure of Form B. The intramolecular hydrogen bonding force between N(1) and NH(22) atoms of Form B is weaker than that of Form A, and the stacking force between the imidazopyridine rings of Form B may also be weaker than that of Form A. Thus, Form A is considered to be a more stable structure than Form B. In DSC analysis, Form B transformed to Form A. Based on these results, phase transformation from Form B to A occurs during a transient fluid state.

We synthesized CeFe 1 − x M x AsO ( M = Mn,Co; 0 ⩽ x ⩽ 0.5 ) by a solid state reaction. The parent compound CeFeAsO undergoes antiferromagnetic order of the Ce 4f electrons at T N = 3.7 K . It is found that the T N decreases with the Mn substitution and becomes below 2 K at x = 0.2, while the Co substitution increases the T N .

High-pressure resistivity measurements are performed on a high-quality single crystal of the β -pyrochlore oxide KOs2O6 in the pressure range of 1.0 to 5.0 GPa. The superconducting transition temperature T c increases slightly from 9.6 K at ambient pressure to 9.8 K at 1.0 GPa, decreases gradually with increasing pressure, and suddenly drops from 6.5 K to 3.2 K across P s = 3.6 GPa . The drop of T c at P s is likely to be related to a change in the rattling vibration associated with a symmetry-breaking structural transition.