Ammoniacal Alkaline Research Articles

Ｎｉ‐Ｗ合金めっき皮膜の高Ｗ含有率化と皮膜特性

A study was conducted to determine the maximum obtainable tungsten content in the alloy, using ammoniacal alkaline citrate baths of pH7.5-9.0 at 80°C. Sodium citrate and citric acid were considered as the complexing agent. The presence of a large amount of sodium in the bath reduced tungsten content and current efficiency. When a suitable amount of sodium tungstate and nickel sulfate were added to the citric acid baths, alloys up to 51wt%W, corresponding to Ni3W, were obtained. Since alloys exceeding 40wt% W were obtained for the first time, X-ray examination and hardness testing were also conducted. Alloys exceeding 44wt% W (Ni4W stoichiometry) were amorphous, having extremely small atomic size. The Vickers hardness of the 44wt% W alloy was Hv 1350 after heating at 550°C for 1h.

Synthesis of Superconducting Y-Ba-Cu-O Powder by the Spray Drying Method

Raw materials for sintering of superconductor were synthesized by the spray drying method. Three kinds of atomized solutions were used: (1) solution of Ba-, Y- and Cu-nitrates, (2) its ammoniacal alkaline solution and (3) slurry made by the mixing of Ba-, Y-, Cu-nitrates solution diluted by the water-ethanol solvents with oxalic acid solution. Resulting powders were calcined up to 900°C. They formed perovskite structure at 850°C ((1), (2)) and 800°C ((3)). Calcinated powders from (1) and (2) showed strongly aggregated or cortinuous structure with many pores, whereas that from (3) was flocculated structure and homogeneity in the mass and each particles. In conclusion, (3) was optimum method to produce the raw materials for sintering of superconductor.

Studies of dinoflagellate chromosomal basic protein

Routine cytochemical methods proved useless in demonstrating basic protein in dinoflagellate chromosomes because when the DNA was removed, these chromosomes dissolved away just as eubacterial nucleoids. However, with ammoniacal silver technique or alkaline Biebrich scarlet, DNA could be kept intact, all the dinoflagellate chromosomes examined gave positive reaction. The acid-soluble proteins were extracted from methanol-fixed Amphidinium carterae and methanol-fixed isolated nuclei of Noctiluca miliaris, and subjected to urea polyacrylamide gel electrophoresis. Only one band of basic protein co-migrating with histone H4 was found. The chromosomes of Oxyrrhis marina can retain their original forms after the removal of DNA. Their chromosomal basic protein can be demonstrated by various cytochemical methods. This protein co-migrates with histone H4 in urea gel too. Its amino acid composition has been determined. This protein can combine with DNA fibril to form a nucleosome-like structure which seems to be corresponding to two of the archaebacterial nucleosome-like structures and may represent the primitive nucleosome.

W-Fe合金の誘起共析におけるWの優先析出

Tungsten-iron alloys were deposited from ammoniacal alkaline tartrate electrolytes in a wide range of metal composition. The iduced codposition was studied by steady-state and galvanostatic pulsed d.c. electrolysis, X-ray diffraction of electrodeposits, and direct chemical analysis of the metal composition of the solution sorbed on the electrode surface. Comparison of alloy composition was made between the alloy obtained by steady-state d.c. electrolysis and the alloys obtained by interrupted galvanostatic pulsed d.c. electrolysis. The result showed that, in the steady state of electrolysis, the tungsten percentage of the metal contained in the solution adjacent to the cathode surface was extremely higher than that in the bulk of the electrolytes having different metal compositions. The result of direct chemical analysis of the solution near the cathode surface showed that the preferential deposition of tungsten was not an anomalous phenomenon. It was found that the preferential deposition of tungsten occurred by the following interaction between electrolytes and cathode materials. (a) There was a preferential adsorption of tungsten in some ionic state, and (b) The tungsten percentage of the metal contained in the adsorbed layer, covering both of non-polarized and polarized electrodes, was higher than that in the electrodeposits.

タングステン-鉄電着合金の組成と構造を決定する機構について

Electrodeposition of iron-tungsten alloys from aqueous ammoniacal alkaline tartrate electrolytes is studied by means of electron diffraction of cathode deposits and chemical analysis of the solution sorbed on them. In resemblance to the adsorption of irregular binany system, the metal component of lower concentration in bulk electrolyte is preferentially adsorbed at non-polarized electrode. This paper describes that this adsorption is important in studying induced codeposition. The electrodeposition of crystalline Fe3W having a non-equilibrium superlattices of DO19 type was found. A geometric requirement for the formation of these crystals was presented. The effect of codeposition of hydrogen on inhibition of this requirement was shown, which accounts for the observed structural transition of alloys prepared under different conditions. The stoichiometry present in the cathode deposits supports the correlation previously proposed between metal composition of electrolyte in the bulk and that at the cathode surface. Qualitative description can be given of the alloy composition using the values of metal composition of ions at the cathode surface and certain reluctance of tungsten in codeposition. This description will be in better agreement with the experimental results on the assumtion that the electrodeposition of tungsten is catalyzed by multiplets of iron atoms deposited in particular geometric structure.

Structure of Noncrystalline Co‐25 a/o W Electrodeposit

Noncrystalline electrodeposits of Co‐25 atomic per cent (a/o) W prepared from ammoniacal alkaline tartrate electrolyte were studied by x‐ray diffraction. A model for the structure of this alloy was developed. The principal assumptions involved in constructing the model are based mainly on requirements for the electrodeposition. The model requires that the alloy consist of distinct basic structural units in the form of tetrahedra, each composed of three cobalt atoms and one tungsten atom. The dimensions of this structural unit correspond to those of the intermetallic compound . Certain criteria govern the bonding of the tetrahedra to form larger aggregates. The scattering function calculated from the model agrees quite well with the diffraction data. The model also accounts for differences in the composition of amorphous deposits prepared at different current densities. The electrochemical requirements for the formation of this structure by electrodeposition are discussed. The operation of similar processes in the electro‐ or chemical deposition of other alloys having stoichiometric composition is considered.

次亜リン酸ナトリウムを還元剤とする無電解ニッケル-鉄リン系合金メッキ浴について

The authors could not prepare an electroless plating bath containing sodium hypophosphite as a reducing agent for depositing iron, but they prepared and classified some kinds of electroless plating baths containing that agent for depositing Ni-Fe-P alloys.The relation between conditions of baths or the rates of deposition and the compositions of alloys was studied in detail on two kinds of baths, ammoniacal alkaline citrate bath (A-C) and caustic alkaline citrate bath (C-C).As the results, the conditions optimum for stable and practical baths were obtained as follows:Ammoniacal alkaline citrate bath (A-C) Caustic alkaline citrate bath (C-C)FeSO4+NiSO4 0.1mol/l 0.1mol/lNaH2PO2 0.2mol/l 0.2mol/lNa-citrate 0.15mol/l 0.25mol/l(NH4)2SO4 0.50mol/l -H3BO3 - 0.50mol/lpH 10 (NaOH) 9 (NaOH)Operating temperature 90±1°C 90±1°CThe plating rate in A-C Bath was usually high and the both contents of iron and phosphorus in the deposited film were low.On the other hand, the plating rate in C-C Bath was relatively low and the both contents of iron and phosphorus in the deposited film were high-The composition of the deposit was easily controlled by the ratios among metallic salts in the bath.

アンモニアアルカリ性無電解コバルト-ニッケル合金メッキ浴

The relation between plating conditions and rate of deposition or composition of plated film was investigated in two kinds of ammoniacal alkaline electroless plating baths (A-T and A-C) for cobalt-nickel alloys of sulfate-hypophosphite system.The results obtained were as follows.(1) The preferable conditions for stable baths having relatively high rate of deposition and giving good appearance of plated film were as follows:Ammoniacal alkaline tartrate bath (A-T) Ammoniacal alkaline citrate bath (A-C)CoSO4+NiSO4 0.1mol/l 0.1mol/lNaH2PO2 0.2mol/l 0.2mol/lNa-citrate - 0.2mol/lNa-tartrate 0.5mol/l -(NH4)2SO4 0.5mol/l 0.5mol/lpH(NH4OH) 9.0 9.0Operating temperature 90°C 90°C(2) Under the above conditions, a desired film composition having any ratio of nickel to cobalt and containing some amount of phosphorus was obtained at a relatively high rate of deposition by controlling the ratio of concentrations of ions between nickel and cobalt in each bath.(3) The plating rate in A-T was higher than that in A-C, but the former gave inferior appearance of deposited film to the latter owing to its lower stability. The plating rates in the both baths were higher than those in single baths (for cobalt or nickel plating) under the same conditions.(4) The utilization efficiencies of hypophosphite in the above baths were usually kept in the range of 20-40% in A-T, and 28-30% in A-C, both of which were higher than that of nickel plating baths and lower than that of cobalt plating baths under the same plating conditions.(5) The phosphorus content in the plated film almost linearly decreased from 2.4 to 1.9% in A-T or from 5.8 to 1.8% in A-C with the increase of cobalt content in the film.

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.

コバルト-ニッケル合金の無電解メッキ浴-カセイアルカリクエン酸浴-

The relation between the plating conditions and the rate of deposition or the composition of plated film on electroless plating bath for cobalt-nickel alloy of sulfate-hypophosphite system was investigated. The results obtained were as follows.1) The following 3 kinds of baths were selected for stable plating baths having relatively high rate of deposition.a) Caustic alkaline citrate bath (C-C)b) Ammoniacal alkaline citrate bath (A-C)c) Ammoniacal alkaline tartrate bath (A-T)2) The preferable conditions for plating bath of C-C type were as follows: CoSO4+NiSO4 0.1 mol/l, Na-citrate 0.2mol/l, H3BO3 0.5mol/l, pH=7(NaOH), and operating temperature 90°C.Under the above conditions, a desired film composition containing phosphorus with any ratio of nickel to cobalt was obtained by controlling the ratio of concentrations of nickel to cobalt in the bath.3) The phosphorus content in the alloy film decreased almost linearly from 14% (in nickel film) to 4% (in cobalt film) with the increase of cobalt content in the film.4) The sum of the rate of deposition in each single bath was almost equal to the rate of the alloy plating bath; however, the ratio of nickel to cobalt in the alloy film did not correspond well with the rate of deposition in each single bath, but a higher content of cobalt than the value calculated from its rate of deposition was always given.

無電解コバルトメッキ皮膜の性状

The plated films of electroless Cobalt deposited from the following 4 kinds of baths were examined macroscopically, microscopically, and by roughness tester; and the effects of fundamental conditions of the bath on the properties of films were investigated.(1) CoSO4 0.07mol/l, NaH2PO2 0.2mol/l, Na-Citrate 0.2mol/l, (NH4)2SO4 0.6mol/l, pH=9-10 (A-C Type bath)(2) CoSO4 0.08mol/l, NaH2PO2 0.2mol/l, Na-Tartrate 0.5mol/l, (NH4)2SO4 0.6mol/l, pH=9-10 (A-T Type bath)(3) CoSO4 0.05mol/l, NaH2PO2 0.2mol/l, Na-Citrate 0.2mol/l, H3BO3 0.5mol/l, pH=7-8 (C-C Type bath)(4) CoSO4 0.05mol/l, NaH2PO2 0.2mol/l, Na-Tartrate 0.5mol/l, H3BO3 0.5mol/l, pH=9 (C-T Type bath)The appearance of the deposit depended on the kinds and concentrations of complexing agents in the bath. Namely, types of the baths were arranged in descending order of the brightness of plated films as follows:A-C>C-C>A-T>C-TWhen the plating was carried out in the bath of the same composition, the film obtained had less bright appearance as the rate of deposition was greater.The surface state of the plated film was worse as the film was more thick, in particular, the tendency was remarkable in the baths of tartrate type.Ammonium sulfate present in ammoniacal alkaline baths improved the surface state of plated films. The optimum concentration of ammonium sulfate was 0.6mol/l. Though thiourea was an effective brightener for these baths, its optimum amount of addition depended on the type and pH of plating baths.

コバルトの無電解メッキにおける析出速度について

The relation between the precipitation velocity and the composition of bath was studied on acidic or alkaline electroless baths consisting of cobalt sulfate and sodium hyposulfite, including buffers and additives. As the results of experiments, it was shown that all acidic baths containing organic acids were not in practical use because of so small precipitation velocity as lower than 1μ/h, while caustic or ammonical alkaline baths containing citrate or tartrate gave a considerable velocity as high as 10-15μ/h at 90±1°C.The precipitation velocity was remarkably increased by the addition of boric acid (0.5mol) into caustic alkaline baths, and the surface state of deposits was improved by the addition of ammonium sulfate (0.6mol) into ammoniacal alkaline bath.The optimum composition of bath for practical use was as follows:(1) Caustic alkaline citrate bath (pH=7-8-NaOH); 0.1mol CoSO4, 0.2mol NaH2PO2, 0.2mol Na-citrate, and 0.5mol boric acid.(2) Caustic alkaline tartrate bath (pH=9-NaOH); 0.08mol CoSO4, 0.2mol NaH2PO2, 0.5mol Na-tartrate, and 0.5mol boric acid.(3) Ammoniacal alkaline citrate bath (pH=9-10-NaOH); 0.07mol CoSO4, 0.2mol NaH2PO2, 0.2mol Na-citrate, and 0.6mol (NH4)2SO4.(4) Ammoniacal alkaline tartrate bath (pH=9-10-NaOH); 0.08mol CoSO4, 0.2mol NaH2PO2, 0.5mol Na-tartrate, and 0.6mol (NH4)2SO4.

医薬品の体内変化に関する研究 (第5報)

New glucuronic acid conjugate was isolated from human urine after sulfisomezole administration, according to the following extraction method. To the urine, was added active charcoal, followed by elution with ammoniacal alkaline solvents, which was absorbed through H-type (A) Dowex 50W-X8, 100-200 mesh, and later extracted with water. Lead acetate precipitates were separated. To the precipitates by basic lead acetate, ammonium sulfate solution and hydrogen sulfide were added to remove lead and then extracted with ammonia after being absorbed through A. The ammonia eluate was evaporated to dryness under reduced pressure and colorless fine crystals, m.p. 170-171° was afforded.According to the synthetic process, potassium salt of N4-carbobenzoxysulfisomezole was condensed with methyl (2, 3, 4-tri-O-acetyl-α-D-glucosylbromid) uronate, and reduced with Pd charcoal. It was hydrolyzed with barium hydroxide, purified by paper partition chromatography and extracted with ammonia after being absorbed through A, and crystals, m.p. 170-171° was obtained. No depression of m.p. by admixture and elementary analysis, ultraviolet and infrared of both compounds extracted and synthesized are in good agreement. Therefore, this compound was identified to be ammonium sulfisomezole-N1-glucosiduronate containing one molecule of water of crystallization.

Complexometric titration of copper (II) using chromotropic acid dioxime as a metal indicator

Chromotropic acid dioxime forms purple coloured complexes with copper in the pH ranges 5.82 to 6.45 and 7.25 to 8.05 respectively which are less stable than the CuII-EDTA complex. On titrating these solutions with EDTA, the purple coloured complexes turn colourless or yellow at the end point. These titrations give satisfactory results in the temperature ranges 20 to 70° C and 20 to 50° C respectively. In acid medium, the titration of copper can be carried out in the presence of magnesium and alkaline earths, but zinc, cadmium, nickel, cobalt, aluminium and iron(III) interfere. The latter two elements can be masked by sodium fluoride. In ammoniacal medium, zinc, cadmium, cobalt, nickel, lead, magnesium and alkaline earths interfere.

Urinalysis method for enriched uranium.

A urinalysis procedure was developed for the estimation of micro-amounts of enriched uranium which are coprecipitated with an ammoniacal alkaline earth phosphate precipitate. The precipitate is fired in a muffle furnace and the enriched uranium purified by anion exchange. The isolated enriched uranium is electroplated and determined by autoradiography. The method has a sensitivity of 0.015 plus or minus 0.007 d/m per 150 ml of sample, a recovery of 94 per cent, and a standard deviation of plus or minus 16 per cent. (auth)