Single Bath Research Articles

Improved Electrodeposited Multilayer Structure by Coulomb Controller

The effectiveness of a coulomb controller in improving the uniformity of multilayer structures was investigated by electrodepositing Co-Cu/Cu multilayers by a potentiostatic single bath method with a target layer thickness of 5 nm. Current analysis and cross-sectional field-emission scanning electron microscopy observations revealed that the layer thickness fluctuated when it was controlled by the deposition time. However, the thickness variation obeyed Faraday's law. Another sample was electrodeposited using a coulomb controller, which controls the layer thickness by the quantity of electricity. The layer thickness was constant in this sample.

Influence of the fluorescent brightener Periblanc BA on the degree of whiteness of the knitted cotton fabric

In this study the influence of the different fluorescent brightener Periblanc BA concentrations on the degree of knitted cotton fabric whiteness was investigated. Two consecutive experimental runs were performed. The first was the bleaching of the knitted cotton fabric with hydrogen peroxide using the methods of two and single bath exhaustion while the second was the optical bleaching with fluorescent brightener Periblanc BA using the exhaustion method. CIE Whiteness Index and Tint value were measured on the Color-Eye 3000 spectrophotometer at the standard illuminant D65 (Ice-Texicon, d/8, D65/10?) while K/S values were determined using the Kubelka Munk equation. The results show that cotton fabric bleached with fluorescent brightener Periblanc BA after bleaching with hydrogen peroxide using two bath exhaustion method has higher degree of whiteness (118.8) with a reddish tint in comparison to the one bleached with hydrogen peroxide using single bath method (106.1).

Effect of a multilayer structure and lubrication on the tribological properties of coatings of Fe-W alloys

The methods for expanding the use of nanocrystalline electrolytic Fe-W alloys by creating a multilayer structure and using oil lubrication were studied. It was shown that lubricants can reduce the coefficient of friction and oxygen penetration into the sliding pairs, thus enhancing the wear resistance behaviour of Fe- W coatings as compared to that at dry friction, when the surface tribo-oxidation dominates. The electrodeposition of multilayer Fe-W/Cu coatings from a single bath was shown to be feasible. The tribological and mechanical properties of such coatings were investigated. The multilayer structure was found to improve the wear resistance characteristics of the coatings even at dry friction and at a relatively high normal load of 10 N.

Electrodeposition of high performance multilayer coatings of Zn–Co using triangular current pulses

Compositionally modulated alloy (CMA) coatings of Zn–Co were electrodeposited on to mild steel from an acid chloride bath containing thiamine hydrochloride, as an additive. Electroplating was carried out galvanostatically from a single bath containing Zn2+ and Co2+ ions. Gradual change in composition in each layer was effected by triangular current pulses, cycling between two cathode current densities. Compositionally modulated alloy coatings were developed under different conditions of cyclic cathode current density and number of layers, and their corrosion resistances were evaluated by potentiodynamic polarisation and electrochemical impedance spectroscopy. The formation of multilayer and corrosion mechanism was analysed using scanning electron microscopy. The corrosion resistances of CMA and monolithic alloy coatings were compared with that of the base metal. Compositionally modulated alloy coating at optimal configuration, represented as (Zn–Co)2·0/4·0/300, was found to exhibit ∼80 times better corrosion resistance compared with monolithic (Zn–Co)3·0 alloy, deposited for the same length of time from the same bath. Improved corrosion resistance was attributed to the formation of n-type semiconductor film at the interface, supported by Mott–Schottky plots. Decrease in corrosion resistance at high degree of layering was found, and is due to lower relaxation time for redistribution of solutes in the diffusion double layer, during plating.

Electrolytic preparation of cyclic multilayer Zn–Ni alloy coating using switching cathode current densities

Cyclic multilayer alloy (CMA) coating of Zn–Ni was developed on mild steel using single bath technique, by proper manipulation of cathode current densities. The thickness and composition of the individual layers were altered precisely and conveniently by cyclic modulation of cathode current densities. Multilayer coatings, having sharp change in compositions were developed using square current pulses. Gelatin and sulphanilic acid (SA) acid were used as additives. Laminar deposits with different configurations were produced, and their corrosion behaviors were studied, in 5% NaCl solution by electrochemical methods. It was observed that the corrosion resistance of CMA coating increased progressively with number of layers (up to certain optimal numbers) and then decreased. Cyclic voltammetry study demonstrated the role of gelatin and SA in multilayer coating. The coating configuration has been optimized for the peak performance against corrosion. The substantial decrease of corrosion rate, in the case of multilayer coatings was attributed to the changed intrinsic electric properties, evidenced by Electrochemical Impedance Spectroscopy (EIS) study. The surface morphology and its roughness were examined by Atomic Force Microscopy (AFM). The surface and cross-sectional view of coatings were examined, using Scanning Electron Microscopy (SEM). X-ray photoelectron spectrum (XPS) study was carried out for surface analysis. The relative performance of pure Zn, monolithic and CMA coatings were compared and discussed.

Effect of AquaVac TM Vibromax TM on size and health of post larva stage of Pacific White shrimp Litopenaeus vannamei and Black Tiger shrimp Penaeus monodon

This study was conducted to evaluate the efficacy of AquaVac™ Vibromax™, an inactivated Vibrio bacterin product, to promote health and resistance to vibriosis in penaeid shrimp post larva (PL). Black Tiger shrimp ( Penaeus monodon) and Pacific White shrimp ( Litopenaeus vannamei) were fed ad libitum with Vibromax TM- enriched Artemia for 10 consecutive days, PL5–PL14. Artemia nauplii were enriched by incubating 150 g Artemia nauplii in 1 L Vibromax TM for 1.5 h prior to feeding. Varying dosages; half, single and two times overdose were compared for their effectiveness. A control group was fed on normal (non-enriched) Artemia. Shrimp PLs were challenged with a single immersion bath of 1.0–1.4 × 10 5 CFU/ml Vibrio parahaemolyticus on day one (PL15) or day seven (PL21) following the 10 day feeding treatment to test their disease resistance, and the survival rates amongst groups were compared. Shrimp PLs were observed for their growth (body wet weight and length) and survival over the experiment until PL23. Histological preparation of the hepatopancreas and other visceral organs were examined for general health condition of the shrimp PLs. The body wet weight and length of shrimp PLs following a 10 day feeding trial indicated that the use of Vibromax TM promoted growth in both Black Tiger shrimp (average length and weight in treated groups at PL23: 1.77 ± 0.08 cm and 26.84 ± 2.50 mg; length and weight in control group at PL23: 1.72 ± 0.19 cm and 22.11 ± 7.19 mg) and Pacific White shrimp PLs (average length and weight in treated groups at PL23: 1.71 ± 0.01 cm and 31.82 ± 2.85 mg; length and weight in control group at PL23: 1.46 ± 0.37 cm and 23.08 ± 12.95 mg). The health promoting effect of Vibromax TM was also supported by the higher survival of PL23 in Black Tiger Shrimp from the treatment groups (average Relative Percent Survival: 52 %, 72 %, and 48 % for half dose, single dose, and two times overdose, respectively). Histological examination of hepatopancreatic tissue from the treated PLs did not demonstrate any adverse effect of the treatments. Although hepatopancreatic inclusion bodies, indicating pathological signs of monodon baculo virus (MBV) infection, were observed in certain populations of Pacific White shrimp PLs, the PLs that received the feeding treatment generally demonstrated better growth and survival than those of the control group. Overall results from the present study support the health promoting effect of Vibromax™ on growth and survival of shrimp PLs. The efficiency varied according to the dosage of Vibromax TM administered and pre-existing health condition of the PL.

Study on dyeing behavior of cotton/organic cotton knitted fabrics

Organic cotton is grown using methods and materials that have a low impact on the environment. Organic cotton is grown and processed without toxic chemicals that can be absorbed easily when in contact with the user\'s skin. This paper describes the dyeing behavior of organic cotton vs conventional cotton to find what will be the significance between them. The ring spun yarns of 40s combed organic (GOTS certified) and ordinary cotton were produced with similar parameters like beating point and settings. Knitted fabrics were produced with similar loop length and weight using organic and ordinary cotton yarn. Both the fabrics were processed in GOTS certified Processing unit using reactive dyes in soft flow machine in single dye bath. Processed fabrics were tested for colour fastness to washing, water, rubbing, perspiration and light. Colour difference and strength were also measured using Spectrophotometer (DATACOLOUR). Presence of metals were also analyzed in both the processed fabrics and reported here. Keywords: Organic cotton, dyeing, fabrics, textile.

Study on Dyeing Behavior of Cotton/Organic Cotton Knitted Fabrics

Organic cotton is grown using methods and materials that have a low impact on the environment. Organic cotton is grown and processed without toxic chemicals that can be absorbed easily when in contact with the user's skin. This paper describes the dyeing behavior of organic cotton vs conventional cotton to find what will be the significance between them. The ring spun yarns of 40s combed organic (GOTS certified) and ordinary cotton were produced with similar parameters like beating point and settings. Knitted fabrics were produced with similar loop length and weight using organic and ordinary cotton yarn. Both the fabrics were processed in GOTS certified Processing unit using reactive dyes in soft flow machine in single dye bath. Processed fabrics were tested for colour fastness to washing, water, rubbing, perspiration and light. Colour difference and strength were also measured using Spectrophotometer (DATACOLOUR). Presence of metals were also analyzed in both the processed fabrics and reported here.

The Effect of Cobalt Addition on Structural and Magnetic Properties of Electrodeposited Iron-Platinum Nanocrystalline Thin Films

Iron-Platinum (Fe-Pt) and Cobalt-Iron-Platinum (Co-Fe-Pt) nanocrystalline thin films were deposited on brass substrates using a single bath electrodeposition system. The effects of addition of various concentrations of cobalt towards the composition, crystallographic structure, microstructure and magnetic properties of the Fe-Pt alloy films were investigated. Ammonium tartrate and ammonia solution were used as complex forming additives to stabilize the Fe2+ and Co2+ ions and to enhance co-deposition with platinum complexes. The as-synthesized thin films were characterized by energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), scanning electron microscopy (SEM) and alternating gradient magnetometry (AGM). EDS results showed that cobalt was preferentially deposited compared to iron during Co-Fe-Pt film electrodeposition. SEM results showed that the microstructure of the films consisted of spherical granules. XRD showed formation of disordered face-centered cubic (fcc) Fe-Pt phase and all peaks were shifted to slightly higher diffraction angles with increasing cobalt content. The average crystallite size calculated from XRD peak broadening varied from 2.33nm to 6.54nm. The saturation magnetization and coercivity increased with increasing cobalt content.

Cooling Classical Particles with a Microcanonical Szilard Engine

The possibility of extracting energy from a system in a cyclic process is discussed. We present an explicit example where a system, initially prepared in a microcanonical state, is able to perform such an operation. The example is similar to the Szilard engine, but the microcanonical initial condition allows one to design a protocol where measurement is not necessary.

One-Step Process for Enzymatic Desizing and Bioscouring of Cotton Fabrics

Textile wet processing is one of the most polluting industrial processes. It is a complex process, and its complexity depends on the composition of textile material. From this point of view, new efficient strategies for cotton wet processing are needed, which are cost-effective and reduce the impact on the environment. The goal of this work is to accomplish most aspects of preparatory finishing (desizing, scouring) by means of “green chemistry,” or, in other words, nontoxic enzymatic treatments. To achieve this goal, a mixture of α-amylase (Am) and polygalacturonase (PG) enzymes from Trichoderma harzianum induced with orange peel was successfully produced. Partial purification of these enzymes using dialysis and chromatographic techniques was carried out, and the purified enzymes were characterized. Different effects on the enzyme activity, including temperature, pH, and surfactant, were studied. The treatment of cotton fabric in a single bath for desizing with Am or a single bath for scouring with PG was accomplished. The treatment conditions were optimized by varying the enzyme concentration, pH value, treatment temperature, and duration. Treatment effectiveness on fabric properties was evaluated via weight loss (%), violet scale shades, residual starch in fabric (%), copper number, tensile strength, and water absorbency (wettability). A combined process for desizing and scouring was applied to the raw cotton fabric using a mixture of Am and PG enzymes. The effect of the two enzyme concentrations at different incubation times on the desizing and bioscouring efficiencies was further studied.

Physical and Chemical Properties of Cotton and Rayon Fabrics Finished by Single Bath and Double Step Methods (In the Case of Using Diammonium Hydrogen Phosphate as Flame Retardant)

Physical and Chemical Properties of Cotton and Rayon Fabrics Finished by Single Bath and Double Step Methods (In the Case of Using Diammonium Hydrogen Phosphate as Flame Retardant)

Electrodeposition of GMR Ni/Cu Multilayers in a Recirculating Electrochemical Flow Reactor

The recirculating electrochemical flow reactor developed at UCLA has been employed to fabricate nanostructured GMR multilayers. For comparison, Ni/Cu multilayers have been electrodeposited from a single bath, from dual baths and from the recirculating electrochemical flow reactor. For a magnetic field of 1.5 kOe, higher GMR (Max. -5%) Ni/Cu multilayers with low electrical resistivity (< <TEX>$10\;{\mu}{\Omega}{\cdot}cm$</TEX>) were achieved by the electrochemical flow reactor system than by the dual bath (Max. GMR = -4.2% and < <TEX>$20\;{\mu}{\Omega}{\cdot}cm$</TEX>) or the single bath (Max. GMR = -2.1% and < <TEX>$90\;{\mu}{\Omega}{\cdot}cm$</TEX>) techniques. Higher GMR effects have been obtained by producing smoother, contiguous layers at lower current densities and by the elimination of oxide film formation by conducting deposition under an inert gas environment. Our preliminary GMR measurements of Ni/Cu multilayers from the electrochemical flow reactor obtained at low magnetic field of 0.15 T, which may approach or exceed the highest reported results (-7% GMR) at magnetic fields > 5 kOe.

Electrodeposition of CuInSe2 in citrate-containing electrolytes

CuInSe2 is a frequent constituent of solar cells. Low-cost solar cells can be prepared by electrodeposition from a single bath, provided that the multiple variables affecting the process can be properly tuned. Our design includes an n-layer of TiO2 (dense and/or nanoporous), on top of which a p-layer of CuInSe2 is electrodeposited. The TiO2 layer is supported on conductive glass. When CuInSe2 is applied onto TiO2, a p–n junction is formed by which sunlight could be transformed into electricity. CuInSe2 films have been prepared by electrodeposition from a single bath aqueous solution. Citrate has been used as complexing agent, so as to shift the copper deposition potential in the negative direction, bringing it closer to the In deposition potential. Films are obtained potentiostatically at −0.8 V (vs. standard calomel electrode) for 1 h. The electrolyte consisted of 0.4 mol/L sodium citrate containing 3 mmol/L CuCl2, 6 mmol/L InCl3, and 5 mmol/L SeO2. Different pH values between 4 and 6 are investigated. The samples are annealed in a furnace under flowing Ar at 350 °C for 15 min, which proves to be essential to improve the crystallinity of the CuInSe2 films. TiO2 and CuInSe2 have been characterized using scanning electron microscopy, X-ray diffraction, and optical absorption spectroscopy. The morphology and the physical and optical properties are in good agreement with those reported in the literature. In order to investigate the photoresponse of the cells, current–voltage curves of prototype devices are performed in the dark and under light.

Microstructure of electrodeposited NiFe/Cu multilayers

NiFe/Cu multilayer films have been electrodeposited potentiostatically on (001)-oriented Si and polycrystalline Cu substrates by a single bath technique. Standard error of mean and energy dispersive X-ray studies of single NiFe(Cu) layers allow us to establish the right deposition parameters for NiFe and Cu sublayer. Standard error of mean results reveal the layered structure of deposits for relatively thick bilayer thickness (ca. approximately 200 nm). The modulated structure of NiFe/Cu multilayers with extremely thin bilayer thickness (nominal period Lambda= 8 nm) was investigated by transmission electron microscope techniques. A columnar structure of the deposit with column diameter in the range from 10 to 30 nm was observed. These results are comparable with X-ray diffraction measurements of crystallites size obtained by Scherer equation. The line scans acquired using EDS confirmed the layered structure of the deposit, but pointed towards possibility of intermixing of species from alternating sublayers especially in case of those with finer period.

Influence of wanning traditional Chinese medicine dipping for newborns on their sleeping quality and appetite

Objective To know the influence of wanning traditional Chinese medicine dipping for newborns on their sleeping quality and appetite. Methods Divided 600 newborns into the traditional Chinese medicine dipping group, swimming group and the single bath group according to their sequence of birth, there were 200 cases in each group. Different nursing cares were used in the different group sepa-rately. Compared the condition of sleep quality and appetite among the three groups. Results The condi-tion of sleep quality and appetite in the traditional Chinese medicine dipping group was significant better than those in the other groups with few cry and scream. Conclusions Wanning traditional Chinese medicine dipping for newborns can ameliorate their quality of sleep and improve their aapetite. Key words: Newborn; Traditional Chinesemedicine; Swimming; Sleep; Appetite

Photocatalytically Generated Bimetallic ( Pt – Au ∕ C – TiO2 ) Electrocatalysts for Polymer Electrolyte Fuel Cell Applications

Heterogeneous photocatalysis was used to prepare bimetallic Pt–Au modified carbon– matrices for use in polymer electrolyte fuel cells. These new generation electrocatalysts were characterized by transmission electron microscopy, energy-dispersive X-ray analyses, X-ray diffraction, and X-ray photoelectron microscopy. The electrocatalytic activity of these materials for the oxygen reduction reaction (ORR) was assessed by rotating disk hydrodynamic voltammetry. Of the three variant scenarios that can be envisioned for photocatalytic deposition of the two metals, i.e., sequential deposition (with Pt first and Au second or Au first and Pt second) or simultaneous deposition of Pt and Au on the nanocomposite surface from a single bath, electrocatalyst samples with Pt decorating the initially deposited Au nanoclusters (designated as ) performed the best in terms of ORR kinetic facility, even relative to the monometallic case of Pt supported on . The durability of these electrocatalysts (in terms of corrosion) was assessed via galvanostatic polarization tests; once again fared best relative to the other two samples as well as the control case. For all the electrochemical analyses, the total metal loading in the electrocatalysts was kept constant at 20% (by mass) for meaningful comparison.

Current-driven, electrically detected ferromagnetic resonance in electrodeposited spin valves

We investigate the ferromagnetic resonance of Co/Cu/Co trilayers by use of AC-spin-transfer torque excitations. Magnetic structures are grown in a 6-μm-thick commercial nanoporous polycarbonate membranes by use of electrodeposition in a cobalt/copper single bath. We show that microwave magnetic excitations corresponding to the uniform mode of the two cobalt layers are electrically detected as a change of the DC voltage of the system.

Synthesis and characterisation of electrodeposited iron–platinum nanostructured thin films

Iron–platinum (FePt) nanostructured thin films were deposited on brass substrates using a novel stable single bath electrodeposition system. Complex-forming additive was added to stabilise the Fe2+ ions. The composition of the electrodeposited film was controlled by varying current density, concentration of the electrolytes and concentration of the complex-forming additive in the electrolyte. The as synthesised FePt films were characterised by energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD) and scanning electron microscopy (SEM). energy dispersive X-ray spectroscopy showed that FePt films deposited from solution with Fe2+/Pt4+ molar ratio of 25 : 25 contained higher amount of Fe, in proportion with increasing concentration of complex-forming additive in the electrolyte. However, FePt thin film with higher platinum content was obtained from solution with Fe2+/Pt4+ molar ratio of 200 : 1 and without complex forming additive. X-ray diffraction characterisation showed formation of disordered face centred cubic FePt in the as deposited films while the Fe-rich film exhibited body centred cubic lattice structure. The average crystallite size of deposited films varied from 4·3 to 39 nm. The crystallite sizes estimated from XRD peak broadening were smaller than the those observed by SEM, indicating that the grains were polycrystalline.

One-bath one-dye class dyeing of PES/cotton blends after corona and chitosan treatment

In this work, the effects of corona discharge (CD) and chitosan treatment on the dyeability of polyester/cotton blends with direct and reactive dyes were studied. The surface chemical changes of polyester and cotton were analyzed using X-ray Photoelectron Spectroscopy (XPS). The correlation between chemical changes, wettability, and dyeability after CD and/or chitosan treatment has been established. Color intensity of both single components and PES/cotton blend increased proportionally with increasing chitosan concentration. The results obtained open the possibility for a new method for dyeing of polyester/cotton blends in a single bath using one dye-class that is commonly used for dyeing of textile material of cellulosic origin.