Kinetics of oxidation of cuprous chloride by oxygen in aqueous hydrochloric acid solutions

The rates of absorption of oxygen into aqueous cuprous chloride solutions containing hydrochloric acid were measured at 15, 25 and 35°C using a baffled agitated vessel operated batchwise and the experimental results were analyzed with the chemical absorption theory. The reaction between oxygen and cuprous chloride was found to be second order, i.e. first order with respect to oxygen and CuCl₂^? ion which is the actual reactive species in aqueous cuprous chloride solutions containing hydrochloric acid. The reaction rate constants were calculated and correlated as a function of temperature.     

Spherical Yttrium Aluminum Garnet Embedded in a Glass Matrix

Containerless processing was used to investigate the glass-forming behavior of Al₂O₃–Y₂O₃ glass. The amorphous bulk samples were obtained at compositions with 25–37.5 mol% yttria when the melt was cooled at a cooling rate of ∼250 K/s. Although small spherical particles (∼10 μm) with the same composition of the matrix were detected in the amorphous samples with 32.5–37.5 mol% yttria, the microfocus X-ray diffraction result indicated that the small spherical particles were crystalline Y₃Al₅O₁₂ garnet (YAG), rather than being amorphous. This observation suggested that small YAG particles could not grow larger after their nucleation, because of the high viscosity at high undercooling and the high cooling rate, which would graze the nose of the continuous cooling temperature diagram of YAG.     

Vapor phase hydroformylation of ethene over Co/SiO2 promoted by noble metals: dynamic in situ diffuse reflectance FT-IR study of surface species

An in situ diffuse reflectance FT-IR technique was employed to investigate the active surface species and the reaction mechanism of the oxygenate formation in the vapor phase hydroformylation of ethene on Co/SiO₂ promoted with various noble metals such as Ir, Rh, Pt, Re, Ru, and Pd. Co(A)/SiO₂ and Ir(CO)/SiO₂ which were derived from cobalt(II) acetate and Ir₄(CO)₁₂, respectively, were quite inactive in the reaction, and showed only quite small peaks of adsorbed CO under the conditions of 1.1 MPa of C₂H₄/CO/H₂ at 298 K. In contrast, Co(A)-Ir(CO)/SiO₂, which were very active in the reaction, exhibited strong absorption bands of linear and bridged CO species. At 423–463 K, propanal adsorbed on the catalyst and acyl species which is suggested as the intermediate for the formation of propanal were also observed on this catalyst. By exposing CO preadsorbed on this catalyst to C₂H₄/H₂ at 289 K and 0.1 MPa, the intensity of the linear CO band decreased, and the bands of propanal and acyl species emerged simultaneously, whereas that of the bridged CO band remained constant after the initial drop. These results suggested that the oxygenates are formed via the CO insertion into adsorbed ethyl species, and linear CO species plays a major role in the CO insertion on these noble metal-promoted cobalt catalysts.     

Dielectric Depression and Dispersion in Electrophoretically Fabricated BaTiO3 Ceramic Films

Dielectric depression and dispersion were observed in BaTiO3 ceramic films fabricated by electrophoretic deposition followed by sintering. The dielectric constants were depressed down to 6800–4600 around the Curie point ( T _C ). The dielectric dispersion occurred above T _C . These dielectric properties are attributable to a surface layer formed during sintering. XRD analysis indicated that the surface layer was a hexagonal-like BaTiO₃ phase. A mixed solvent of acetylacetone and alcohol employed in the present work may have been responsible for the formation of the surface layer.     

Effect of perchloric acid on the molecular weight and yield of poly-THF

Polytetramethylene glycol (molecular weight range 1000–8000) was prepared by the polymerization of tetrahydrofuran (THF) using a binary catalyst system of fuming sulfuric acid and perchloric acid. When 28% fuming sulfuric acid alone was used as the catalyst, the average molecular weight of polymer was low, the maximum value being 1000–1100. By the combination of fuming sulfuric acid with a small amount of perchloric acid, the average molecular weight of the polymer was increased to about 8000. Furthermore, the molecular weight was readily controlled in the range of 1000 to 8000 by varying the amount of the binary catalyst.     

Anodic polarization of aluminium in organic electrolytes

The polarization characteristics of aluminium anodes have been studied in various organic electrolytes containing aluminium chloride. The small amount of oxide present on the metal was dissolved by an anodic pre-treatment. The charge transfer number of the overall reaction was three. The current density supported by the electrolytes decreased in the order nitromethane>acetonitrile >propylene carbonate, formamide>tetrahydrofuran. The rest potential increased in the order formamide     

Development of flexible organic light‐emitting diode on barrier film and roll‐to‐roll manufacturing

To come out with a successful organic light‐emitting diode (OLED) lighting business, it is very important to have clear differentiation of OLED from LEDs. Flexible OLED has merits, such as capability to be mounted on the curved wall, which is not easy for LEDs to achieve the feature. There are several approaches to make flexible OLEDs especially among those plastic barrier films that can bring high level of flexibility, which could not be achieved by any conventional lighting method. In this paper, barrier films with various water vapor transmission rate values, including 10^{? 6} order, are applied, and the conditions to have almost no dark spot growth under 85 °C and 85% high temperature/humidity test are shown. Flexible OLED panels are manufactured with the world's first roll‐to‐roll equipment using plastic barrier film.     

Texture and Formation Mechanism of Fibrous Calcium Hydroxyapatite Particles Prepared by Decomposition of Calcium–EDTA Chelates

The texture of fibrous calcium hydroxyapatite (Ca₁₀-(PO₄)₆(OH)₂, CaHAP) particles that were prepared by the decomposition of calcium–ethylenediaminetetraacetic acid (calcium–EDTA) chelates at 100°C under various pH conditions (pH values of 5–10) was investigated by various means. Well-crystallized fibrous CaHAPs were produced at pH .6. The stoichiometry of the CaHAPs with a chemical formula of Ca_{10− x} (HPO₄) _x (PO₄)_{6− x} (OH)_{2− x} (H₂O) _x was improved by increasing the decomposition pH. All the CaHAPs had unit-cell dimensions of a = 0.9436 ± 0.0003 nm and c = 0.6881 ± 0.0006 nm, exhibiting an enlarged a value. The finding of mesoporosity of CaHAPs by nitrogen gas (N₂) adsorption measurement indicated that the CaHAPs were produced by an agglomeration of primary particles. Furthermore, the nonstoichiometric CaHAPs that formed at pH 6 developed ultramicropores, which were accessible to water (H₂O) molecules but not to N₂ molecules, by the elimination of H₂O molecules that were adsorbed in interstices of primary particles in less-orderly crystallized CaHAPs and/or by dehydration of HPO₄²⁻ groups. These findings by gas adsorption techniques could give evidence for the agglomeration mechanism to attain a polycrystalline CaHAP, although they exhibited good crystallinity with large size.     

破伤风毒素及其片段的纯化

本文报道了破伤风毒素及其片段AB、BC、A和C的纯化方法。应用硫酸铵沉淀和Ultrogel AcA_(34)凝胶过滤制备的纯化毒素,于SDS-PAGE和PAGE中均形成单一的蛋白带,分子量为15万,pI为5.95,毒力为1～3×10~4MLD/μg。毒素经DTT还原、尿素处理、再用Ultrogel AcA_(44)凝胶过滤制备A和BC片段。A片段的分子量为54000,pI为4.8。BC片段的分子量为98 000,pI为7.2。木瓜酶处理毒素后用高压液相层析制备AB和C片段。纯化的AB片段分子量为98 000,于等电聚焦中为2条主要区带,pI为5.3和5.5,另有数条小区带;纯化的C片段分子量为51000,于PAGE中形成5条蛋白带,于等电聚焦中主要区带的等电点为7.3,另有几条小区带。     

Ethylene carbonate-based organic electrolytes for electric double layer capacitors

A new electrolytic solution based on a mixed solvent of ethylene carbonate (EC) with sulfolane (SL) or -butyrolactone (-BL) has been examined as an electric double layer capacitor. Fundamental properties, such as electrolytic conductivity, viscosity, and thermal stability, were measured for solutions containing quaternary alkylammonium salts as the supporting electrolyte. Maximum conductivities were obtained for the solutions with mixed solvent of 20–40 mol % EC in the EC+-BL system: 1.2–1.3×10^–2S cm^–1 for EC+-BL dissolving 0.5 M Et₄ NBF₄ (Et=C₂H₅). The electrochemical and the thermal stabilities of the solution were dependent on the electrolytic salt as well as the solvent composition. A stable discharge capacitance and a high coulombic efficiency were obtained in a model capacitor using carbon fibre electrodes and the organic electrolyte of EC+-BL/Et₄NBF₄ (or EC+-BL/Et₄NPF₆).