Increasing Bath Temperature Research Articles

Damping of quantum coherence: The master-equation approach.

We solve the master equation for the coordinate-coordinate damped harmonic oscillator for initial superpositions of coherent states. In the zero-temperature case the solution remains a simple superposition of coherent states. While the underdamped oscillator evolves all initial superpositions into mixtures of coherent states the overdamped oscillator does so selectively. For finite temperatures coherent states are no longer preserved, and we find a decrease in the variance of the off-diagonal coordinate-basis density-matrix elements below the coherent-state value. This variance decreases with increasing bath temperature. In the overdamped case there is negligible associated spreading of the diagonal coordinate-basis density-matrix elements. Thus the coordinate basis is an example of Zurek's pointer basis and the coordinate damped oscillator models the coordinate-basis density-matrix diagonalization which occurs in a coordinate measurement.

ＥＤＴＡ溶液からの銀‐パラジウム合金電析

Silver-palladium alloy deposition from alkaline solutions containing EDTA, ammonium carbonate, and ammonia water has been studied. The cathodic potential for alloy deposition was -0.37V (vs. SCE) which was between those of Ag+ and Pd2+ single ion solutions. It was found that the silver deposition became the condition of diffusion controll, when palladium was deposited. This deposition of silver-palladium alloy was an anomalous codeposition, and the palladium content of electrodeposited alloy was always smaller than that of the electrolyte. The amount of palladium codeposited tended to increase with an increased in bath pH or current density, and decreased with an increase in bath temperature. Cathode current efficiency was about 70% irrespective of bath temperature. It improved with an increase in pH, and tended to decrease with higher current density.The electrodeposit of silver-palladium alloy had a crystal structure with no remarkable orientation. SEM photographs showed good adhesion and a smooth surface with no cracks.

Calcium buffering and slow recovery kinetics of calcium-dependent outward current in molluscan neurones.

Calcium entry into molluscan neurones during depolarizing voltage-clamp steps activates an outward current which on repolarization decays over periods of more than 30 sec. This slowly decaying tail current was used to study the relation between calcium buffering in cytoplasm and the decline of a calcium-activated membrane process. Calcium-dependent outward current was also studied after injection of calcium into the cytoplasm. The time course of the fall of outward tail current was much less sensitive than tail current amplitude to the amount of calcium entry. Increasing bath temperature from 5 to 15 degrees C decreased the rate of fall of outward tail current activated by calcium entry. In contrast, outward current activated by calcium injection declined more rapidly at higher temperatures. Injection of sufficient EGTA to give maximum depression of outward current during depolarizations reduced the amplitude of outward tail current by at most 50%. After EGTA injection outward tail current declined more rapidly immediately following repolarization, but returned to base line at about the same time as the control. After injection of EGTA, outward current activated by calcium injection was reduced or completely blocked, and returned to base line more rapidly. Application of the mitochondrial uncoupler carbonyl cyanide m-chlorophenyl hydrazone (CCCP) did not alter the decay time course of outward tail current, but markedly prolonged the decline of outward current activated by calcium injection. The slow kinetics of outward tail current were compared to predictions of the concentration of calcium ions at the outermost surface of a spherical model cell following calcium influx. We conclude that after depolarization and calcium entry, the diffusion and binding of free calcium to cytoplasmic buffers plays a key role in determining the rate of fall of outward tail current. Further, different mechanisms influence the decline of calcium-dependent outward current following injection of calcium into the cytosol.

Chloride baths for PbSn alloy deposition

In this paper, chloride baths of suitable composition for the electrodeposition of Pb-(5%–60%)Sn alloys are described. The tin content of the deposit increased with an increase in either the current density or the tin content of the bath and with a decrease in either the agitation of the bath or the temperature. At higher current densities and plating times the deposits became powdery. The grain size of the electrodeposited alloy increased with increasing bath temperature and decreasing current density. X-ray diffraction studies showed that the alloys were crystalline in nature. The cathode current efficiency was between 64% and 93%, depending on the bath composition and the operating conditions.

しゅう酸浴におけるクロムめっきの電流効率

The cathodic current efficiency for chromium deposition from oxalic acid baths containing, chromic acid and ammonium sulphate, has been examined over a wide range of bath compositions and plating conditions. High current efficiencies were obtained in baths containing 100g/l total chromium, 48g/l hexavalent chromium, 75g/l (NH4)2SO4. The current efficiency increased with decreasing current density and bath pH, and with increasing bath temperature. At the best current efficiencies, however, bright chromium deposits were not obtained, and to obtain bright chromium deposits, hexavalent chromium concentration should be 12-38g/l.

ＥＤＴＡ浴による高速度無電解銅めっきの反応機構

Mechanisms of high-speed electroless copper deposition from EDTA bath were investigated by means of analytical method, X-ray diffraction and electrochemical method. From the analysis of bath components and the reaction products such as copper and hydrogen gas during the electroless copper deposition at 70°C, it was confirmed that the following reactions were occurring in the bath.Cu deposition reaction: Cu(II)-EDTA+2HCHO+4OH-→Cu+2HCOO-+H2+2H2O+EDTA…(1)Cannizzaro reaction: 2HCHO+OH-→CH3OH+HCOO- …(2)The reaction (2) was remarkably promoted by the increase of bath temperature above 60°C and pH higher than 12.5. X-ray diffraction data of the powdery deposits which have been obtained by 1 hour mixing of CuO and Cu2O powders with the Cu-EDTA bath at 60°C showed that the reducing power of the solution containing both formaldehyde and EDTA was higher than that of the solution containing each component separately. In the former case, the added Cu2O was completely reduced to metallic copper. This fact suggests that the spontaneous decomposition of the EDTA bath does not occur through the formation of Cu2O contrary to the case of Rochelle salt bath, but spontaneous decomposition starts in the bath either by copper particles removed from the surface or by the reduction of metallic copper when the reducing power of the solution increases. The mixed potential theory of the reaction (1) was also studied by potential sweep method.

ＥＤＴＡ浴による高速度無電解銅めっきの延性に及ぼす添加剤の影響

Effects of various additives on the high-speed electroless copper deposition from EDTA bath were investigated. By electron-microscopic observation of the surface of copper deposit from the additive free EDTA bath, it was shown that the surface consisted of fine and easily fallen off particles that would cause spontaneous decomposition of the bath when they fell off into the solution. Single use of ferrocyanide, potassium nickel cyanide, or sodium nitroprusside as additive in EDTA bath improved the ductility of the copper deposits to some extent, and the deposits from these baths provided the surface consisting of small pyramidal crystals at 50°C, which grew to larger and more leveled grains at 70°C. As previously reported, the authors found that the ductility of copper deposit was remarkably improved when 2, 2'-dipyridyl and the other compound, e.g. potassium nickel cyanide, were added together into the EDTA bath. Electron-micrographs of copper deposits from these baths contaning two additives provided the surfaces apparently more leveled than those from the baths containing each additive individually. Thus the corelation between ductility and surface leveling was confirmed. Ductility of copper deposit and deposition rate increased with increasing bath temperature up to 80°C, beyond the temperature deposition rate decreased because of the predominance of Cannizzaro reaction. Further addition of some kinds of nonion type surface active agents into the plating bath was found to give favorable effects on the ductility of the deposit.

Influence of water temperature on thermal, circulatory and respiratory responses to muscular work.

Different muscular exercises have been executed on a bicycle ergometer during immersion in water, the temperature of which varied between 20 and 40 degrees C. During submaximal works, O2 consumption was not modified by the temperature of the water. On the other hand, body temperature (rectal and muscular) are clearly influenced by environment. The temperature of the quadriceps varies from 37.7-38.5 degrees C when the bath temperature rises from 20-40 degrees C during the same work intensity corresponding to 1/3 of the individual maximal work capacity. The rectal temperature was always lower about 0.5 degrees C. Ventilation and heart rate underwent modifications which were significantly accentuated in hot water. Maximal O2 consumption does not reach its highest level in cold water. The low muscular temperature observed in these conditions seems to limit the aerobic metabolism and the working of the muscles. Maximal O2 consumption then rises in parallel with the increase in bath temperature and in body temperatures. In very hot water however (40 degrees C), when rectal temperature rises unduly, the circulatory demand linked to thermolysis becomes excessive, and maximal O2 consumption decreases.

An X-Ray Study on the Micro Strain and the Coherently Diffracting Domain Size in Electrodeposited Chromium

It is recognized that electrodeposits are similar in microstructure to the microcrystals produced by cold work and the crystals with high internal stress and preferred orientation.In order to obtain the knowledge of microstructures in chromium, electrodeposited from a chromic acid plating bath as a function of bath temperature, the X-ray diffraction line profiles of its deposits were analysed by Fourier series method which was practicable by using a single reflection only. The information on micro strain, coherently diffracting domain size was obtained from the Fourier cosine coefficients. Moreover, the effect of unresolved Kα line profile and Kα1 line profile separated by Rachinger's graphical method on the r.m.s. strain and the domain size were examined. From the experimental results, the following conclusions have been derived.(1) The value of r.m.s. strain obtained by using unresolved Kα line profile is a little larger than that in the case of Kα1 diffraction line profile separated by Rachinger's graphical method, but the domain she is slightly small in the case where unresolved Kα line profile was used.(2) It is found that the r.m.s. strains in electrodeposited chromium analysed on the (211) diffraction line profiles have decreased with increasing bath temperatures, in the range of 40 to 70°C, and again increased at 75°C. The influence of bath temperature on the stored energy and the dislocation density derived from the mean squared strain show a similar tendency as the r.m.s. strain. The coherently diffracting domain size in electrodeposited chromium on the (211) diffraction line profile has increased with increasing bath temperature, in the range of 40 to 70°C, and again decreased at 75°C.(3) The reflecting plane dependence of the r.m.s. strain and the domain size in electrodeposited chromium obtained from bath temperature of 60°C have been investigated on the three planes of (110), (200) and (211). It is found that the r.m.s. strain has increased in the order (200), (211), (110) and the domain siza in (211) plane is smaller than that in the case of (110) and (200) planes, but between the domain size in (110) and (200) planes, no marked difference has been recognized.

The X-Ray Investigation of Internal Stress in Electrodeposited Chromium

It is well known that the internal stress in electrodeposited metals is varied by the electrolytic conditions and the internal stress effects on some properties of the electrodeposited metals.Therefore, it is important to measure the internal stress in electrodeposited metals. Hitherto, many workers have developed the methods to measure the internal stress in electrodeposited metals. The principles of those methods are based on the measurement of deflection of a thin strip or a spiral helix which is electrodeposited on the one side. These methods do not give a direct information on the lattice deformation in electrodeposited metals.The X-ray diffraction methods are expected to give more exact information on the lattice distortion in electrodeposited metals. Recently, a number of X-ray diffraction methods for stress measurements have been developed in the field of the testings for metallic materials. The authors applied these X-ray diffraction methods to measure the internal stresses in electrodeposited chromium. In order to measure the internal stress of the first type (macro stress) in electrodeposited chromium by Sin2ψ method, the authors modified an ordinary diffractometer to be fulfilled the following conditions: (1) the specimen axis can be fixed at an arbitrary angle, the receiving slit and the GM tube being made to scan. (2) the receiving slit and the GM tube can be slided precisely to the focusing point in the radial direction of the goniometer which corresponds to the value of ψ0. The errors in this stress measurement which is apt to be caused by the sliding of the receiving slit and the GM tube were determined at 2θ=0°, and the influence of deviation in the position of the receiving slit from the focusing point on the measured value of stress was discussed by measuring the stress free iron powder. In measuring the internal stress of the second and third type (micro strains) in the electrodeposited chromium, the half-value breadth of several diffraction lines were measured by using Cu-Kα radiation and Hall's equation was applied to determine the micro strains.The chromium was plated on annealed copper plate from a bath containing CrO3:250g/l, H2SO4:2.5g/l and current density was 60A/dm2. The range of thickness of the deposits was from 10 to 30μ.From the experimental results, the following conclusions were derived.(1) It was confirmed to be possible to measure accurately the internal stress of the first type by using the modified diffractometer.(2) It was found that the internal stress of the first type in electrodeposited chromium measured by Sin2ψ methed on (211) diffraction line with Cr-Kα radiation was tensile stress at bath temperature range of 40-65°C, and the stress decreased with increasing bath temperature, and above 70°C the stress was compressive stress.(3) The half-value breadth of (211) diffraction line with Cr-Kα1 radiation decreased with increasing bath temperature from 40°C to 75°C.(4) It was found that the internal stress of the second and third type was a maximum at bath temperatures of 40-50°C. This tendency corresponded to the results of deflection obtained by a thin strip contractometer which showed a maximum value at bath temperatures of 40-50°C.

Preferred orientations in nickel electro-deposits: II. A consideration of the effect of deposition conditions on the textures developed

The theory of texture development in nickel electro-deposits, proposed in Part 1 of this paper, is used here to explain the trends of texture changes which result from variations in nickel deposition conditions. Only the commonly-reported <210>, <100> and <110> orientations are considered. The occurrence of systematic texture changes (with increase of temperature and current density and with addition of oxidizing agents) is indicated in the experimental data of previous workers. It is suggested that an increase in bath temperature leads to a decrease in the average surface concentration of adsorbed hydrogen atoms, and thus to changes of textures towards free growth, i.e., <210> → <100> → <110>. This conclusion is completely in agreement with experiments conducted, at a pH less then 5. The slight free growth trend observed with an increase of current density is tentatively ascribed to differences in the-slopes of the free growth η- i curve for different singlecrystal faces of nickel. The addition of oxidizing agents — it is argued — reduces surface coverage and hence produces texture changes towards free growth. Some limitations of the present work are indicated.

STUDIES ON ACRYLIC FIBER

The wet spinning of dimethyl formamide solution of acrylonitrile copolymer into the glycerine bath was investigated. The results obtained on the effect of bath temperature are as follows.(1) The spinnability that is, maximum spinning velocity, increases with increasing bath temperature and increases with decreasing output and the viscosity of polymer solution.(2) Decrease of maximum draw ratio of undrawn filaments with increasing bath temperature is not particularly large.(3) The effect of bath temperature upon dry tensile strengths of drawn filaments varies with the draw ratio of these filaments. When the draw ratios of the filaments are small, the above mentioned effect is not distinct. On the other hand, when the draw ratio of the filament becomes larger, the lower the bath temperature, the larger the dry tensile strength. As to the dry tensile elongation, this effect is also not distinct.(4) As to the dry knot strength and elongation, the effect of the draw ratio is larger than that of the bath temperature.(5) The initial moduli and the toughnesses calculated from stress-strain curves of drawn filaments become larger with decreasing bath temperature, The similar results may be obtained for the elastic recovery characteristics.(6) At lower bath temperatures, the textures of filaments obtained by wet spinning become compact or dense as the desolvation or the diffusion of the solvent is comparatively slow. On the contrary, at elevated bath temperature, owing to the higher speed of desolvation, the contrast between skin and core become clearer, and it may be seen that there are many microscopic holes in the core zone.These differences in the texture of the filaments coinside with those results obtained from the specific gravities and ratios of the cross sections.

STUDIES ON ACRYLIC FIBER

The wet spinning of dimethyl formamide solution of acrylonitrile copolymer into the glycerine bath was investigated. The results obtained on the effect of bath temperature are as follows.(1) The spinnability that is, maximum spinning velocity, increases with increasing bath temperature and increases with decreasing output and the viscosity of polymer solution.(2) Decrease of maximum draw ratio of undrawn filaments with increasing bath temperature is not particularly large.(3) The effect of bath temperature upon dry tensile strengths of drawn filaments varies with the draw ratio of these filaments. When the draw ratios of the filaments are small, the above mentioned effect is not distinct. On the other hand, when the draw ratio of the filament becomes larger, the lower the bath temperature, the larger the dry tensile strength. As to the dry tensile elongation, this effect is also not distinct.(4) As to the dry knot strength and elongation, the effect of the draw ratio is larger than that of the bath temperature.(5) The initial moduli and the toughnesses calculated from stress-strain curves of drawn filaments become larger with decreasing bath temperature, The similar results may be obtained for the elastic recovery characteristics.(6) At lower bath temperatures, the textures of filaments obtained by wet spinning become compact or dense as the desolvation or the diffusion of the solvent is comparatively slow. On the contrary, at elevated bath temperature, owing to the higher speed of desolvation, the contrast between skin and core become clearer, and it may be seen that there are many microscopic holes in the core zone.These differences in the texture of the filaments coinside with those results obtained from the specific gravities and ratios of the cross sections.