Magnetic properties of Europium-graphite intercalation compound C6Eu

An ordered state with a complex magnetic structure has been observed below 4CK. The magnetization for H ⊥ c (c; the c-axis) shows a field-induced phase transition from a small magnetic moment state ( ～ 0.6μ_B) at lower fields to a larger moment one ( 2.2 - 2.5μ_B) above 25kG. The transition field depends on temperature and is found to be 5 - 2kG. The magnetization for H//c has only a sublinear field dependence. Above 40K the magnetic susceptibility obeys the Curie-Weiss law with θ = +1.3K and the molar Curie constant C_m = 6.78, which suggests that Eu ion is divalent in C₆Eu.     

Preparation of stable aqueous suspension of a hydrophobic drug with polymers

Pharmaceutical preparation of a hydrophobic aldose reductase inhibitor 5-(3-ethoxy-4-pentyloxyphenyl)-2,4-thiazolidinedione (CT112) was investigated. CT112 dissolved in a basic solution with different kinds of polymers was neutralized by acid to obtain a suspension preparation. In particular, the addition of a polymer, hydroxypropyl methyl cellulose (HPMC) provided a stable CT112 suspension with a homogeneous particle size, and there seemed to be an optimal concentration of HPMC for the stable suspension. The addition of polysorbate 80 brought higher CT112 solubility in water, but did not provide a stable suspension. X-ray diffraction, IR spectrum, and thermal analysis revealed that the particles in the suspension with HPMC had lower degree of crystallinity, less hydrophobic particle surface, and lower melting point and decreased fusion enthalpy than the suspension without HPMC. These results suggested that the highly stable CT112 suspension could be attained by the adsorption of the polymer.     

Phenomenological features in a model with non-universal gaugino CP phases

We study phenomenological features in an extended gauge mediation SUSY breaking model that has non-universal gaugino masses and CP phases. We show that large CP phases in soft SUSY breaking parameters can be consistent with the constraints coming from the electric dipole moment (EDM) of an electron, a neutron, and also a mercury atom. Masses of the superpartners are not necessarily required to be larger than 1 TeV but allowed to be O(100) GeV. We also investigate the mass spectrum of Higgs scalars and their couplings to gauge bosons in that case. Compatibility of this model with the present experimental data on the Higgs sector is discussed.     

Synthesis of aromatic polyimines by the condensation of aromatic dialdehyde and diamine

Film-forming aromatic polyimines were prepared by low temperature solution polymerization of aromatic dialdehyde and aromatic diamine usingm-cresol. The polymerization proceeded rapidly to give high molecular weight polyimine solutions. Fibrous polymers were precipitated by pouring the solutions into anhydrous methanol. Lemon yellow-to-orange films were cast in situ from the reaction solutions. The polymers showed typical C=N stretching absorption near 1620 cm^?1 in infrared spectra and had high glass transitions of over 200 ?C but showed low crystallinity.     

Space group determination of the BaY(Cu0.5Fe0.5)2O5+δ phase using a convergent-beam electron-diffraction technique

The space group of the BaY(Cu_0.5Fe_0.5)₂O_5+δ (δ=0.03-0.17) phase was studied by selected-area electron diffraction and convergent-beam electron diffraction (CBED). The CBED patterns for BaY(Cu_0.5Fe_0.5)₂O_5.03 grains taken from the zone axes of [111], [001] and [010] had the symmetries of m, 4mm and 2mm, respectively. Forbidden reflections were observed neither in selected-area electron diffraction nor in the CBED patterns. From these results, the space group of the BaY(Cu_0.5Fe_0.5)₂O_5.03 was determined to be P4/mmm. Since the presence of a mirror plane parallel to the (Cu,Fe)O₂ planes was confirmed, Cu and Fe were found to be randomly distributed in the (Cu,Fe)O₂ planes. The same analyses were performed for BaY(Cu_0.5Fe_0.5)₂O_5.17 grains and the space group was also found to be P4/mmm. The change in the magnetic properties of BaY(Cu_0.5Fe_0.5)₂O_5+δ samples due to the high-pressure heat-treatment was concluded to be caused by excess of oxygen.     

Reaction of 2,5-diisopropyl- and 2,5-di-sec-butylpyrazine 1-oxide. Derivatives with phosphoryl chloride and acetic anhydride

In order to examine the α-substitution of side chains, various derivatives of 2,5-diisopropyl- and 2,5-disec-butylpyrazine 1-oxides were subjected to the reaction with phosphoryl chloride and acetic anhydride. Chlorination and acetoxylation were recognized to take place on the pyrazine ring in almost all cases.     

Other Classes of Minimax Estimators of Variance Covariance Matrix in Multivariate Normal Distribution

It is well known that the best equivariant estimator of the variance covariance matrix of the multivariate normal distribution with respect to the full affine group of transformation is not even minimax. Some minimax estimators have been proposed. Here we treat this problem in the framework of a multivariate analysis of variance (MANOVA) model and give other classes of minimax estimators.     

α-quartz型GeO2高压相变的分子动力学研究

采用在经典离子晶体作用势中附加Ｍｏｒｓｅ势,并进行必要的量子化修正,对α－ｑｕａｒｔｚ型ＧｅＯ２结构随压力变化特性,进行分子动力学计算模拟,获得了在压力高于６．０ＧＰａ,α－型ＧｅＯ２从晶相向非晶相相变的模拟结果,并利用其摩尔体积变化,键角、径向分布１、配位数等重要信息对模拟结果作了深入的探讨,相变后的非晶相,由占体积６６％的八面体结构和３３％的四面体结构组成的非晶体,其中还有极少量的α－ｑｕａｒｔｚ型ＧｅＯ２存在。     

Model calculation for ion mobility in air using the MOBCAL program

We determined new potential parameters for a calculation of ion mobility in air using the MOBCAL program. In our model, we regard air as a virtual uni-atomic molecular gas. And the Lennard-Jones parameters for various kinds of atoms in molecular ions were determined with simple and systematic methods. Using these parameters, we have calculated the mobilities of product ions from chemical warfare agents, normal saturated hydrocarbons, and illicit drugs. Most of the calculation results showed good agreement with the experimental values. Therefore this calculation method will be useful for understanding of the ion mobility spectrometry in air.