Complexation of the Non-steroidal Anti-inflammatory Drug Loxoprofen with Modified and Unmodified β-Cyclodextrins

The inclusion complex of the anti-inflammatory drug, loxoprofen, with -cyclodextrin-(CD), sulfated -CD, and glycerol ether -CD was studied by UV-VIS absorption and ¹H-NMR spectroscopy in solution. The inclusion complex of loxoprofen with -CDs was prepared by freeze-drying, and then characterized in the solid state by thermal analysis, X-ray diffraction, FT-IR and FT-Raman spectroscopy, and scanning electron microscopy (SEM). Furthermore, a physical mixture of loxoprofen/-CD (1/1, mol-%) in the solid state was also characterized. The solubility of the loxoprofen increased on addition of -CDs. The solubility enhancement of the loxoprofen with -CDs is in the following order: glycerol ether -CD > sulfated -CD > -CD.     

Magnetic properties of the spinel-type

The spinel sulphide CuCr₂S₄ is a metallic ferromagnet with a Curie temperature , while CuHf₂S₄ has no magnetic anomaly. Magnetic properties of the quaternary spinel-type Cu(Cr_1-xHf_x)₂S₄ system have been studied. With increasing x the ferromagnetic properties are weakened gradually from a predominant ferromagnetic, a spin-glass, finally to a simple paramagnetic behavior. For the composition of x0.50, a re-entrant spin-glass phase could emerge, even though the Curie temperature is ill-defined as a ferromagnetic phase boundary. Specimens with x≥0.90 remain paramagnetic down to 4.2 K. A spin crossover phenomenon is found around 160 K in the specimens of x=0.50–0.70. A step-like anomaly is manifestly detected in the magnetization, which corresponds with the change of the spin state. This crossover indicates that the spin state converts from high temperature S=2 into low temperature states. In the ordered states in , the magnetic moment originates from only Cr³⁺ ions.     

Microbial degradation of poly(butylene succinate) by Fusarium solani in soil environments

The use of mulch made of biodegradable plastic in agriculture is expected to help solve the problem of the enormous amount of plastic waste emission, and to save the labor of removing the mulch after harvesting crops. In this study, we isolated a microorganism possessing the ability to degrade one of the promising biodegradable plastics, poly(butylene succinate) (PBS), and investigated the degradation characteristics of the microorganism in soil environments. Fungal strain WF-6, belonging to Fusarium solani, that had not been reported could be isolated from farmland as the PBS-degrading microorganism. Strain WF-6 degraded 2.8 percent of the PBS in a 14-day experimental run in a sterile soil environment, as determined by measuring CO₂ evolution. Furthermore, we ascertained that the degradability of strain WF-6 was enhanced by co-culturing with the newly isolated bacterial strain Stenotrophomonas maltophilia YB-6, which itself does not show PBS-degrading activity. We then investigated the effects of cell density of the indigenous microorganisms in the soil environments on the degradability of the co-culture of strains WF-6 and YB-6 by inoculating these strains into non-sterilized and partially sterilized soils, which contained 10⁸, 10⁶, and 10³ CFU/g-dry solid of soil of indigenous microorganisms. The degradability strongly depended on the cell density level of the indigenous microorganisms and was remarkably diminished when the cell concentration level was the highest, 10⁸ CFU/g-dry solid. Quantitative PCR analysis revealed that the growth of strains WF-6 and YB-6 was inhibited in the non-sterile soil environment with the highest cell density level of the indigenous microorganisms.     

Development and application of Halanay-type theory: Evolutionary differential and difference equations with time lag

We consider extensions, developments and modifications of a result due to Halanay, and the application of “Halanay-type inequalities” in the analysis and numerics of retarded functional-differential equations, difference equations, and retarded functional-difference equations. Our emphasis is on the variety, structure and development, and future development, of Halanay-type results and their applications. We classify and present novel results of Halanay type (linear and non-linear, discrete, semi-discrete, and continuous) and establish their relevance to delay-differential equations, discretized analogues (we consider ?-methods), and difference equations. A rôle for such results in stability and contractivity analysis is made apparent.     

Classical/Non‐classical Polyoxometalate Hybrids

Two polyanions [Se^{I V}₂Pd^II₄W^VI₁₄O₅₆H]^11? and [Se^{I V}₄Pd^II₄W^VI₂₈O₁₀₈H₁₂]^12? are the first hybrid polyoxometalates in which classical (Group 5/6 metal based) and non‐classical (late transition‐metal based) polyoxometalate units are joined. Requiring no supporting groups, this co‐condensation of polyoxotungstate and isopolyoxopalladate constituents also provides a logical link between POM‐Pd^II coordination complexes and the young subclass of polyoxopalladates. Solid‐state, solution, and gas‐phase studies suggest interesting specific reactivities for these hybrids and point to several potential derivatives and functionalization strategies.     

Intercalation of phenylethylamines intoα-zirconium phosphate and characterization of intercalates

The intercalation of phenylethylamines into-zirconium phosphate has been investigated by the pH titration method.dl-1-Phenylethylamine (dl-PEA) is taken up in two stages. New phases were obtained: Zr(HPO₄)₂(dl-PEA) · H2O in the first, and Zr(HPO₄)₂(dl-PEA)_/43· H₂O in the second stage. 2-Phenylethylamine (2-PEA) also is loaded in two stages, but the first end point is not observed clearly. A new phase, Zr(HPO₄)₂(2-PEA)₂ · H₂O has been formed at the second stage. The new phases have been characterized by elemental analysis, X-ray diffractometry, thermal analysis and IR spectroscopy.     

The dielectric constant of PbTe at 4.2 K and\tilde v=84.15 cm-1, 96.97cm−1, 103.60cm−1

The dielectric constant of a PbTe epitaxial layer has been measured by surface wave spectroscopy using an optically pumped far-infrared laser and the technique of attenuated total reflection.     

Dielectric properties of thin sections of barium titanate ceramics

Thin sections in the thickness range down to 3–5 μm were produced from bariumtitanate ferroelectric ceramics. The small signal dielectric constant, as well as hysteresis loops were measured. Significant deviations from the bulk properties were observed, when the thickness of the sample was decreased to the average diameter of the grains. The measured results are discussed proposing a model with internal stresses and a distorted surface layer.     

Isothermal depolarisation currents in triglycine sulphate: Polarisation along non-ferroelectric crystallographic axes

d ∝t^-s, where s<1 at the initial state and s>1 at the final state of the sample depolarisation. The loss peak frequency 1/τ_p exhibits an activation character of ω_p∝exp(-E/kT) with E=0.25 eV in the direction of the a -axis and E=0.56 eV for the c-axis. Received: 13 February 1997/Accepted: 7 April 1997     

Ferroelectricity associated with the metastable phase “III” of AgNO3

The dielectric constant, dc resistance, D-E ferroelectric hysteresis loop and dilatometric analysis of the three phases I, II, and III of AgNO₃ single crystals has been studied over the temperature range 100–200° C. A ferroelectric behaviour of the metastable phase III was detected here for the first time similar to what happened in KNO₃. The ferroelectric is attributed here to Ag⁺-ion vacancy formation in the unit cell of AgNO₃. The energy activating the process of vacancy formation was found to beE _v=2.6 eV. It was found that an ionic shift from one lattice point to another requires an amount of energy to overcome a potential barrierE _m=0.1 eV. A model is suggested to explain such behaviour. Dilatometric analysis indicated that this metastable phase transition III is accompanied by an expansion of the unit cell.