Modified peniotron using a TE11 rectangular waveguide cavity

This paper proposes a modified peniotron which is expected to increase both handling power and conversion efficiency compared with the original peniotron, and reports the analytical results or its operational characteristics using some computer simulations. Analytical results assuming the fundamental operation of ω₀ ? ω_c at l0GHz show that an extremely high transverse efficiency of nearly 100% may be attainable over a considerably wide range of output power. The tube uses a TE₁₁ rectangular waveguide cavity instead of the double-pair ridged waveguide cavity used for the original peniotron.     

Effect of Maillard Reaction on Some Physical Properties of Ovalbumin

Ovalbumin freeze-dried with or without the addition of glucose was stored at 50°C and 65% relative humidity to study the effect of the Maillard reaction on some physical properties of ovalbumin. In the early stage of the reaction in which ovalbumin-glucose complexes were formed, there were soluble types of monomer and aggregates of which α-helix and available lysine contents were gradually decreased with length of storage and degree of aggregation. These compounds were characterized by properties possessing a marked resistance towards destruction of conformation and coagulation. With progress of the reaction, ovalbumin-glucose complexes changed to insoluble forms having higher particle weight and breakdown products.     

Preparation of blood globin through carboxymethyl cellulose chromatography

A simple and inexpensive procedure for globin preparation from blood of various animals was developed in order to use globin as human food. Carboxymethyl cellulose was most effective among some cation exchangers tested, although amounts of haemoglobin applied to 1 g of the exchanger should be limited to less than 70 mg. The behaviour of adsorbing haem or haemin to the exchanger could not be explained only by a general theory of ion exchange chromatography. Yields and Fe contents of globin preparations from various haemoglobins by this procedure ranged from 67 to 80% and from 0.008 to 0.03% respectively, except for a chicken haemoglobin sample.     

Crystalline Phase Change in Yttria-Partially-Stabilized Zirconia by Low-Temperature Annealing

Changes in the phase composition and microstructure of yttria-partially-stabilized zirconia by low-temperature annealing were investigated at 100° to 500°C using bodies sintered from coprecipitated fine ZrO₂-Y₂O₃ powders at varied temperatures. Tetragonal zirconia on the surfaces of bodies sintered at <1500°C transformed to the monoclinic phase at 100° to 400°C. Transformation behavior was strongly affected by grain size.     

Effects of Antimony Oxide on the Characteristics of ZnO Varistors

The breakdown voltage, the upturn voltage, and the nonlinearity of the ZnO varistors are significantly influenced by the Sb₂O₃ and SiO₂ contents, as well as by the β→γ transition of the Bi₂O₃ phase. The lattice parameter of spinel is influenced by the coexisting Bi₂O₃ phase. Antimony oxide disperses into the powders of ZnO and other additives in the early stage of sintering, and finally gathers again as particles of spinel which may play an important role in the improvement of the nonlinearity by stressing the interfaces of two ZnO grains.     

Recrystallization and Phase Transformation in Reaction-Sintered Sic

Reaction-sintered Sic specimens prepared at ∼1500°C and heat-treated at ∼1850°C in the presence of molten silicon were examined by transmission electron microscopy. The β-Sic grains in as-prepared specimens grew to a large size when heat-treated in the presence of molten Si; the number of growth twins in such °-Sic crystals was very small. The boundary areas of α- and β-Sic crystals were microsyntactic, consisting of thin strips of α- and β-Sic after heat-treating. These changes were due mostly to thin lamellar growth of α-Sic into β-Sic grains along the basal plane. There is also a high density of similar growth of transformation twins in β-Sic crystals. The results provide clear evidence of in situ solid-state transformations in sic.     

A PROPOSAL FOR DIGITIZATION OF LIQUID-LIQUID DISTRIBUTION DATA

Abstract

A spline function has been employed to interpolate liquid-liquid distribution data by producing a function representing a smoothed curve through the points. The data for divalent metal extraction by trioctylamine, tributyl-phosphate and hydroxyoxime are examined in order to test the utility of interpolation with this function.     

SOME METHODS FOR ANALYSIS OF SOLVENT EXTRACTION DATA AND THEIR APPLICATIONS

Abstract

Three programs develpoed to analyze data for liquid-liquid extraction of metal have been applied to the calculation of the stability constants of aqueous cadmium(II)-thiocyanato complexes by using the data for the extraction of tricaprylmethylammonium salt in benzene. The resulting stability constants of the aqueous thiocyanato complexes determined were: for the trial and error method log β₁ = 2·97, log β₂ = 3·70, log β₃ =3·50 and log β₄ =3·28; for the Gauss method log β₁ = 2·91, log β₂ = 3·70, log β₃ =3·35 and log β₄ = 3·29; for the Newton-Gauss method for log β₁ = 2·47, log β₂ =3·24, log β₃ =2·29 and log β₄ = 2·85     

CHARACTERISTICS OF RECTANGULAR MIXING VESSELS

Abstract

The convective diffusion equation of aerosols in the case of gas stream slip on the fibre cylindrical surface has been solved by means of the finite element collocation method. Half-analytical form of the solution makes it possible to examine directly changes the slip causes in the distribution of solids around the fibre surface. Concentration profiles and deposition efficiency computed by this method differ from the experiment results less than those obtained by the common method of finite differences. Additionally the finite element collocation has proved to converge more rapidly than that of finite differences (at optimal conditions of calculation for both methods).¹⁰     

Acidity Control and Catalysis of Pentasil Zeolites

Acidities of pentasil zeolites were measured and correlated with aluminum content using the following methods: (1) Acid-base indicator method, (2) NH₃-TPD spectra, (3) GC pulse adsorption of pyridine and 4-methylquinoline, and (4) FTIR spectroscopy of adsorbed pyridine.

By controlling the acidity of pentasil zeolites, we have succeeded in obtaining high catalytic performance both in paraselective dealkylation of cymenes and in vapor-phase Beckmann rearrangement of cyclohexanone oxime to ?-caprolactam. In the dealkylation, moderate acidity of Li-ZSM-5 was the key to avoid side reactions while keeping a high conversion of cymenes. In the Beckmann rearrangement, neutrality and crystallinity of the pentasil zeolite were keys to obtain a high lactam selectivity, and a high lactam selectivity of 95% was attained by the surface treatment with chlorotrimethylsilane. The active sites were elucidated to be neutral silanols on the external surface of zeolite.