Bath Conditions Research Articles

Spinning of Peanut Protein Fibers1

Abstract Raw Altika peanuts were blanched, partially defatted, ground and the protein was removed using an aqueous alkaline extraction, precipitated at pH 4.0 and freeze dried to yield a protein concentrate with 85.5% protein, 3.1% fat and 2.0% ash on a dry weight basis. Peanut protein concentrate was used to produce dope solutions for the spinning of fibers. Viscosity of dope solutions increased rapidly with increases in protein concentration from 11 to 14%; the highest protein concentration gelled within a short time after mixing. Dope solution viscosity increased with increasing NaOH concentration from 0.85% to 0.90%. Higher NaOH concentrations, up to 1.05%, however, resulted in a continued decrease in dope viscosity. Dope viscosity increased as a function of maturation time, especially at NaOH concentrations that yielded the highest viscosities. The best conditions for spinning peanut protein fibers were: 1) dope pH 11.4, 2) maturation time of 12 hours for a 13.0% protein dope or 2 hours for 13.5% protein dope, 3) coagulating bath conditions of 2N acetic acid and 20% NaC1, and 4) dope extrusion pressure of 15 psi. Suitability of dope solutions for spinning depended on the interaction between protein concentration, pH and dope maturity.

The analytical and experimental determination of the temperature of a specimen during upquench and quench and its influence on recrystallization

SUMMARY The mean temperature of commercially pure aluminium slabs, upquenched in a heat treatment bath and (down) quenched in water, was determined theoretically and experimentally ; analysis and experiment were found to be in close agreement. The same theoretical approach was then used to estimate the relative times for different specimens to absorb the same amounts of heat energy. The assumption that geometrically different specimens of the same degree of cold work require the same amount of specific heat energy input to effect recrystallization was made. Thence, with the aid of experimentally determined times for complete recrystallization of specimens of any given thickness, each with different amounts of prior cold work, the theory was employed to predict recrystallization times for Eipecimens of different thicknesses but with the same amounts of cold work. In this way, the times for recrystallization of any specimen, for given material and upquench and quench bath conditions, with any amount of cold...

Online optimal control of arc impedance for an electric-arc-furnace model

The dynamic behaviour of an electrode-position control system for an industrial direct electric-arc furnace is investigated. The electrode-positioning servomechanism is modelled as an electromechanical system with transfer-function relationships and nonlinear valve characteristics defining the hydromechanical system. The electrical-power-transmission-system model is based on single-phase circuit equations and incorporates an empirical arc-discharge characteristic. A dynamic representation of the supply system is also used which incorporates a linear model of an equivalent synchronous machine including both transient and subtransient effects. Dynamic performance of the conventionally controlled system is investigated by analogue/hybrid simulation of the nonlinear-system model. Optimal and suboptimal control of a linearised model is also studied, and methods of solution based on dynamic programming and the algebraic matrix Riccati equation are compared. To investigate online calculations of optimal control, various forms of performance functional are considered. Conventional 4-mode control and linear optimal control of arc impedance are applied in real time by process computer to the analogue-simulated nonlinear-system model. The study demonstrates a relative improvement in the dynamic performance of arc current, and hence power, with changing bath conditions and varying arc-discharge characteristics.

Pneumatic Barrier and Beach Pollution

The feasibility of improving the bathing conditions of certain beaches by using pneumatic barriers both with and without chlorination was determined by an experimental system consisting of four parallel lines (three air and one water-chlorination) encompassing approximately 355 ft (108 m) of beach, under a mean tidal value of 7.2 ft (2.2 m), a complete cycle of approximately 12 hrs 15 min and a net water exchange of 1,600,000 gal (6,000 cu m). Air was supplied by two 100 scfm (2.8 standard cu m/min) compressors and was sparged through 1/64 in. or 1/32 in. (0.4 mm or 0.8 mm) orifices spaced at 30 in. (76.2 cm) intervals, at conditions assuring critical velocity across the orifices. The conclusions of these studies were: (1) Aeration alone had no statistically significant effect in lowering bacterial levels or acting as a bacterial barrier; (2) chlorination effectively reduced all bacteria levels in the basin; and (3) pneumatic curtains appear effective in containing surface debris and contamination such as oil spillage.

Dynamic Modeling and Estimation of Carbon in a Basic Oxygen Furnace

This paper describes an approach to dynamic modeling and on-line carbon estimation based on waste gas analysis in a basic oxygen furnace. As is well known, the basic oxygen process for steelmaking is highly stochastic in nature. There is, at present, no satisfactory model for predicting the decarbonization rate of the process. The first part of this paper considers approaches to on-line dynamic modeling. A two-stage dynamic model is developed using time-series analysis and empirical information on the decarbonization rate. This model is put in a state-vector form which is ideal for online estimation and control. The second part of the paper applies linear and nonlinear filtering to estimate the carbon and the decarbonization rate of the process during each heat. Since there is a time delay between the bath conditions and the measurements, the state of the system must be predicted. Two different methods for prediction are given. One is based on the present estimate of the carbon in the bath, and the other is based on the present estimate of the decarbonization rate of the bath. A combination of the two schemes is shown to provide better results than those achieved so far in practice. A total of 175 heats from a 220-ton BOF are processed and analyzed, and the results are discussed.

Studies of Detergency

The difficulty or ease of soil removal from soiled fabrics has been studied. Cotton, nylon, polyester, and wool fabrics were soiled with five oily soils and were laundered with eight different detergents under various washing conditions. Variable bath components were surfactant types, water hardnesses, detergent concentrations, and bath temperatures. The contribution of such fabrics, soil, detergents, and bath conditions were estimated by the analysis of variance. The contributions of these factors increase in the following order: (a) (Fabric) > (Fabric) X (Soil) > (Soil) > (Others) when water hardness is chosen as a variable; (b) (Fabric) > (Concentration) > (Fabric) X (Soil) > (Soil) > (Others) when detergent concentration is chosen as a variable; (c) (Fabric) > (Fabric) X (Soil) > (Others) when wash temp erature is chosen as a variable. For each condition, the detergent contribution of fabric is the largest, while that of mutual interaction between fabric and soil is also very large. , The analysis of variance suggested that the difficulty or ease of soil removal is determined mainly by the combination fabric and soil; the type of fabric or the mutual interaction between fabric and soil is also an important factor in deter mining the degree of soil removal. Surfactants are classified by pattern analysis, based on the detergent contribution of the various factors in detergent systems.

アンモニアアルカリ性無電解コバルトメッキ膜の磁性に及ぼすメッキ条件の影響

Effects of pH, temperature, and composition of bath on magnetic properties of deposited films were studied for two sorts of ammoniacal alkaline electroless cobalt plating baths.The results obtained were as follows.(1) The films deposited from ammoniacal alkaline baths had the maximum flux density (Bs) of about 9, 000 gauss, coercive force (Hc) of 200 oersted, and squareness of 0.5-0.7 in general. The variations in the above values of films depending upon plating conditions were found to be less than those of films deposited from caustic alkaline baths reported in the previous paper.(2) In general, citrate bath (A-C type) was stable and gave films of higher squareness. However, the magnetic properties of these deposits greatly depended upon pH and concentration of complexing agents.(3) Tartrate bath (A-T type) was less stable than citrate bath and generally gave films of lower squareness. However, the dependence of coercive force of these films upon the bath conditions such as pH and concentration of complexing agents was little.(4) The difference in the effects of plating conditions of the both baths on the magnetic properties of films was systematically explained by each characteristics of the baths.

ケイフッ酸系黒色クロムメッキ浴の検討

Various kinds of black chromium plating baths have hitherto been reported in literatures. However, the bath composition is not yet established in actual practice at present. Physical and chemical properties of these deposits and the mechanism of their coloration are not also thoroughly researched.The authors examined black chromium plating baths in the literatures and found out that the bath containing hydrogen silicofluoride gave the plating with least powdery deposit and strongest adhesion; but its unevenness in color was most enormous among the platings from these kinds of baths.Plating conditions for the most even black color were researched and the following results were obtained.(1) The optimum composition of bath and plating conditions were as follows:CrO3 300g/l Bath temperature above 10°CH2SiF6 above 1g/l DK 30-50amp./dm2(2) Sulfuric acid should completely by removed, because its presence limited the range of black color. Hydrogen silicofluoride should be supplied to the bath according to its electrolytic comsumption.(3) Higher throwing power was obtained by coating the substrate with copper or nickel, and then, immediately plating black chromium on that coating.

ヒドラジンを還元剤とする無電解コバルト-ニッケル合金メッキ

The fundamental condition of electroless plating of cobalt-nickel alloy (the plating bath contained hydrazine as a reducing agent) or the relation between plating rate and the composition of deposited film was investigated.The results obtained were summarized as follows.(1) Caustic alkaline tartrate bath was selected as a practical plating bath having relatively high plating rate and bath stability.(2) The optimum plating condition of the bath was determined as follows with respect to plating rate, bath stability, and appearance of plated film.CoCl2+NiCl2=0.05mol/lCoCl2/NiCl2=variableN2H4⋅2HCl=1.0mol/lNa-tartrate=0.4mol/lThiourea=3p.p.m.pH=12.0(NaOH)Temperature=90°C(3) The decomposition of bath, or a drawback during such a process of plating, was much prevented by the addition of 2-3p.p.m. of thiourea without depression of plating rate.(4) Under the above condition of bath, various alloys containing any ratio of cobalt to nickel were obtained by controlling the ratio between the both metals in the bath.

ヒドラジンを還元剤とする無電解コバルトメッキ

The relation between the plating rate and the bath conditions were studied on electroless cobalt plating baths containing hydrazine as a reducing agent, and the properties of the deposited film were investigated in comparison with those from the baths containing hypophosphite.The following results were obtained.1. Caustic alkaline tartrate bath was selected for a suitable bath having a relatively large plating rate and a good stability, and its optimum conditions were as follows:CoCl2 0.05-0.08mol/l Thiourea 2-4ppmN2H4⋅2HCl 1.0mol/l pH 12.0(NaOH)Na-tartrate 0.4mol/l Bath temperature 90°C2. The appearance of the deposit was bright when the thickness of the film was less than about 2μ, but it changed to be dull when the film was thicker. The surface state became more deteriorated with the increase of film thickness.3. It was found that the deposit consisted of α-cobalt polycrystals, being the same as the deposit from hypophosphite baths. However, the grain size of the present deposit was in the range of 200-400Å which was larger than that from hypophosphite baths (100-200Å).4. It was also found that the deposit was a ferromagnetic substance having coercive force (Hc) of about 100oe., maximum magnetic flux density (Bs) of 11, 000-13, 000 gauss, and squareness (Br/Bs) of 0.4.

The lattice constants and magnetic anisotropy constants of electrodeposited single crystal films of hexagonal close-packed nickel

Abstract Conclusive evidence has been obtained to show that nickel may be electro-deposited to form a single crystal hexagonal structure, provided that correct bath conditions and suitable substrates are used. The measured lattice spacings of hexagonal close-packed nickel, a = (2·50 ± 0·01) A, c = (3·98 ± 0·06) A, agree well with the values expected. Tentative measurements of the magnetic anisotropy constants K 1 and K 2 have also been made and for films 500 A thick have been shown to be respectively.

Electrodeposited Composite Coatings

SummaryExperiments investigating a novel method of preparing composite coatings are described. In this method, the dispersed phase, which may be fibrous or granular, is incorporated into a metallic matrix by suspending the fibres or particles in a plating bath suitable for electroplating the matrix material. Provided that the bath conditions are suitably adjusted, the resultant metallic plating will have the dispersed phase distributed evenly through it. Fibre and particle reinforced coatings have been made in this way and the results of a study of bath parameters on the quality of the coatings are presented. Some properties of particle reinforced coatings, notably alumina-nickel and self-lubricated coatings formed by codepositing graphite powder in a copper matrix, have been evaluated and the results are presented.

Electrodeposition of Amorphous Selenium

Amorphous selenium coatings have been electroplated in thicknesses up to 30 µ (1.2 mils) on bright nickel cathodes (and thicker coatings can be prepared). Data are given for studies leading to the selection of the optimum bath and operating conditions for the formation of reproducible, uniform, and adherent deposits. It is shown that the plating baths employed and the amorphous deposits obtained are extremely sensitive to a variety of conditions, thus emphasizing the need for further study of the electrodeposition of selenium in the amorphous form.

The Structure of Electro‐Deposited Nickel

An electron diffraction study was made on the crystal structure, orientation, and mode of growth of nickel deposits from sulfate‐chloride‐boric acid and chloride‐boric acid baths under various bath conditions. The effect of pH, temperature, concentration, current density, mechanical stirring, etc., and of additions such as hydrogen peroxide, nickel nitrate, and sodium chloride was investigated on polycrystalline substrates. Depending on bath conditions various preferred orientations (one‐degree), mixed or otherwise, were developed and their causes have been discussed in detail. These have been correlated also with the mode of cathodic crystal growth process.

COAGULATION EFFECT ON FINE STRUCTURES OF REGENERATED CELLULOSE

In this paper, fine structures of cellulose gels coagulated freely in a single-bath such as H2SO4 or H2SO4 Na2SO4 baths, were investigated. Effects of bath composition, temperatue, acid-alkali ratio and degree of ripeness of viscose are examined and discussed.Although it appears that this bath produces regenerated cellulose in a single reaction, it is appearent that gelatination and regeneration processes must still occur either simultaneously ar in some definite, relative succession, depending upon the bath conditions. On the basis of above suggestion, all experimental results could be explained satisfactorily from a point of fundamental view confirmed in the previous study.

Studies of the Dyeing of Nylon with Acid Dyes

The rate of uptake by nylon of nine acid dyes and 21 binary mixtures thereof have been determined at pH 3 and 75° C. using infinite dye bath conditions. The results have been analyzed by a modified diffusion equation in which the flux of dye is assumed proportional to the gradient of activity of the dye on the fiber. This equation enables the adsorption of two dyes to be treated and leads to the result that the uptake of dye 1 is proportional to that of dye 2, a fact which is confirmed by the experimental data. The slope of a graph of the uptake of dye 1 versus dye 2 is related to the ratio of the diffusion coefficients, the affinities of the dyes for the fiber, and the concentrations of the dyes in the bath. Using diffusion coefficients deduced from the rate of uptake of the dyes taken singly, the affinity difference of each binary pair has been calculated. The results obtained are discussed with reference to affinity data on the same dyes obtained by desorption techniques.

Effect of Rapid Cathode Rotation and Magnetic Fields on Crystal Orientation in Electrodeposited Metals

Crystal orientations in metals electrodeposited on a cathode rotating at 3000 rpm were studied by electron diffraction; results were compared with those on a stationary cathode. It was found that orientation could (a) be destroyed, (b) be changed to another type, or (c) remain unchanged. These observations were satisfactorily explained by considering the effect of the forced convection of rotation on the nature of the diffusion layer surrounding the cathode and, thus, on the amount of hydrogen codeposited, the latter being known as an important factor controlling the crystal orientation in electrodeposited metals. Under bath conditions used in this work, presence of a magnetic field of 5400 gauss strength, either perpendicular or parallel to the cathode, had no effect on the types of crystal orientation in iron, nickel, and cobalt deposits. However, when the field was perpendicular to the cathode, the surface of these deposits became very rough and covered with projections protruding in the direction of the field. A possible explanation, of this observation was given.

Electrolytic Hexagonal Nickel

Conditions governing the formation of electrolytic hexagonal nickel in baths containing , , and were investigated. A mixed structure of face‐centered‐cubic and hexagonal‐close‐packed forms was always present in deposits made from baths containing a relatively large amount at higher current densities (>0.2 amp/dm2) and lower bath temperatures (<40°C). Deposits with a mixed structure are found to contain more occluded hydrogen than deposits with a simple face‐centered‐cubic structure. The possible connection between higher hydrogen content and the presence of the mixed structure under certain bath conditions is discussed.

酸性平爐に依るニツケル合金鋼の精錬

This paper deals mostly with an action of oxygen during the refining of steel. For determinat ion of oxygen in steel, Herty's aluminium method was adopted. Complete analyses of both steel and slag were made in each stage from melt down to tap in studying the bath condition. adefinite conclusion was made from the results obtained.FeO content of the slag which may be indicated by the color charts tells fairly well the nature of the heat. Appearance of steel samples taken from the bath at the final stage of the refining indicates fairly well the kind of heat obtained.The bath condition can be estimated by the type of carbon curve obtained by plotting the carbon content of the bath at each stage, especially at the time of the lime addition.Silicates in steel are extremely harmful to steel and should therefore, be removed first at the boiling stage. The formation of silicates in the bath may be prevented by working the heat in such a manner that the silicon will not be reduced. This may be done by the use of lime stone during the working of the heat.Silicates formed at the final stage of melting may be removed according to the wellknown Stokes' principle.

The Thompson-Yates and Johnston Laboratories Report

THIS new volume of the “Thompson-Yates and Johnston Laboratories Reports” opens with obituary notices of the Rev. Stephen Yates, to whose munificence the Thompson-Yates Laboratories owe their foundation, and of Prof. Nocard. The preliminary report of the trypanosoma expedition to Senegambia of the Liverpool School of Tropical Medicine occupies two-thirds of the volume, the authors being Mr. Dutton and Dr. Todd, to whom praise is due for the careful and detailed account of their journey and researches. (This has also been published as a separate report.) The laboratory methods of investigation are first described, and the results of the examination of a number of natives and of various animals for the presence of trypanosomata are then detailed. Only a small proportion of natives was found to be infected, and various experiments on the transmission and pathology of the trypanosoma are given at length. Horses were found to suffer from a fatal trypanosoma disease differing apparently in some respects from nagana. Trypanosomes were also detected in a number of birds, frogs, tortoise, mice, &c. The report is copiously illustrated, and forms an important contribution to the subject of trypanosomiasis, the appended bibliography being a very full one. Mr. Theobald adds notes on the species of mosquitoes collected in this expedition. Among these is a new species coming very near Stegomyia, for which a new genus is created, Catageiomyia. Prof. Ronald Ross contributes a brief article on a new human parasite, the Leishmann-Donovan body, which has already been referred to in these columns (NATURE, vol. lxix. p. 495). Messrs. Glynn and Matthews give some interesting details of the numbers of bacteria and their variation under different conditions in swimming baths, and Dr. Stephens and Prof. Boyce detail the examination of a diseased haddock, with description of a parasite the nature of which is not clear. The general “get-up” of the volume maintains the standard of its predecessors, paper, printing, and illustrations all being excellent. The Thompson-Yates and Johnston Laboratories Report. Vol. v. (New Series). Part ii. December, 1903. (Published for the University Press of Liverpool by Longmans, Green and Co.) Price 12s. 6d.