Concentrations Of Copper Sulfate Research Articles

Evaluation of copper-tolerant fungi isolated from Sarcheshmeh copper mine of Iran.

Mycoremediation, a subset of bioremediation, is considered an advanced method to eliminate environmental contaminations. To identify tolerant fungi to copper contamination and study the related gene expression, sampling was carried out from the soil of "Sarcheshmeh Copper Mine," which is one of the biggest open-cast copper mines in the world. A total of 71 fungal isolates were obtained and purified. Afterward, the inhibitory effect of different concentrations (1000, 1500, 3500, 4000, and 5500 ppm) of copper sulfate on mycelial growth was evaluated. Results indicated that only 5500 ppm of copper sulfate inhibited fungal growth compared to the control. Based on the bioassay experiments, three isolates including S3-1, S3-21, and S1-7, which were able to grow on solid and broth medium containing 5500 ppm of copper sulfate at different pH conditions, were selected and identified using molecular approaches. Also, laccase and metallothionein gene expression has been assessed in these isolates. According to the molecular identification using ITS1-5.8S- ITS2 region, isolates S3-1 and S1-7 were identified as Pleurotus eryngii, and isolate S3-21 belonged to the genus Sarocladium. In addition, P. eryngii showed laccase gene expression reduction after 8 days of exposure to copper sulfate. While in the genus Sarocladium, it increased (almost 2 times) from 6 to 8 days. Besides, metallothionein gene expression has increased from 6 to 8 days of copper sulfate treatment compared to the control which reveals its role in copper tolerance of all studied isolates. In this study, Pleurotus eryngii and Sarocladium sp. are introduced as heavy metal tolerant fungi and the related gene expression to copper tolerance was studied for the first time in Iran.

Green Synthesis of Copper Nanoparticles Using Citrullus colocynthis Peel Extract and Antibacterial Activity for Biomedical Applications

A novel and green method was developed to synthesise copper nanoparticles (CuNPs) using Citrullus colocynthis peel extract as a sustainable source. The study is the first to utilise this extract for the environmentally safe and economically efficient synthesis of CuNPs. The impact of experimental parameters, including the copper sulfate concentration, extract volume, reaction time, and temperature, on the synthetic procedure was thoroughly investigated. The as-prepared CuNPs were characterised using HRTEM, FESEM, XRD, EDX, UV–vis spectrophotometry, and FTIR spectroscopy. The CuNPs exhibited a spherical morphology with an average particle size of 9 nm, and the calculated d-spacing values were measured at 0.257 nm. Furthermore, the XRD analysis revealed characteristic diffraction peaks at 2θ angles of 44.56°, 56.1°, and 71.4°. The UV–Vis absorption spectra of the CuNPs displayed a surface plasmon resonance (SPR) peak at 335 nm, corresponding to an energy band gap of 3.47 eV. Further, the FTIR spectra confirmed the interaction between copper and the biomolecules present in the extract, providing evidence of the significant role played by organic compounds in the capping process. The as-prepared CuNPs exhibited strong antibacterial activity against both gram-negative (P. aeruginosa and E. coli) and gram-positive (S. aureus and S. epidermidis) bacteria.

Dissolution of gold in the presence of copper ion and diethylenetriamine (DETA)

ABSTRACT Cyanidation is the most widely used technique for gold extraction worldwide. However, its efficiency in gold extraction has decreased due to gold association with base metals such as copper. Copper is known to form different complexes with cyanide depending on the pulp pH. These Cu-CN complexes deplete the pulp of free cyanide, thereby decreasing gold leaching. The study examined the application of diethylenetriamine (DETA) in cyanidation to minimise copper ions effect on gold cyanidation. Leaching tests performed in the presence of copper ions reduced gold recovery from 93% to 15% at a copper sulphate concentration of 1% and increased cyanide consumption by 10%. The introduction of DETA (between 0.2% and 1%) however restored gold recovery back to normal as the baseline without copper ions and also enabled gold extraction at a reduced cyanide strength. Based on the study, DETA could be used during gold–copper cyanide leaching to minimise the copper ion effect and enhance gold extraction.

Gibberellin (GA3) and Copper Sulfate Pentahydrate (CuSO4·5H2O) Reduce Seeds per Fruit and Increase Fruit Quality in Bac Son Mandarin Fruit

The aim of this study was to find the optimal gibberellic acid (GA3) and copper sulfate (CuSO4·5H2O) concentrations to reduce the number of seeds and increase the quality of Bac Son mandarin fruit. In experiment 1, the control plants (without GA3) were sprayed with water, and the remaining plants were sprayed with different concentrations of GA3 (50, 75, 100, or 125 ppm). In experiment 2, the control plants (without CuSO4·5H2O) were sprayed with water, and the remaining plants were sprayed with different concentrations of CuSO4·5H2O (50, 75, 100, or 125 ppm). Spraying GA3 at 100 ppm in 2018 produced the lowest seed number and the highest theoretical yield. In 2019, spraying GA3 led to a lower seed number and a higher actual yield compared with the control. Similarly, spraying CuSO4·5H2O significantly reduced the number of seeds/fruit and significantly increased the theoretical yield in 2018. In 2019, the total number of seeds/fruit was significantly lower in the CuSO4·5H2O treatments than in the control. Importantly, both GA3 and CuSO4·5H2O treatments did not adversely affect the fruit’s biochemical parameters or yield. These findings demonstrate that spraying GA3 or CuSO4·5H2O at a certain concentration can effectively reduce the number of seeds per fruit in Bac Son mandarin without compromising fruit quality or yield.

Films of Poly(Hydroxybutyrate) (PHB) and Copper with Antibacterial Activity.

Poly(3-hydroxybutyrate), PHB, is a hydrophobic biopolymer with good mechanical and barrier properties. However, neat PHB is a semicrystalline polymer with a relative high degree of crystallinity and poor film properties. In this work, this biopolymer was plasticized with glycerol tributyrate and functionalized with copper (II) sulfate, allowing us to obtain biodegradable antimicrobial flexible films. Films with the minimum inhibitory concentration (MIC) of copper (II) sulfate presented a higher roughness than neat PHB films. The presence of plasticizer significantly improved the copper sulfate diffusion process, which was evidenced by a greater inhibition halo for plasticized materials compared to unplasticized ones, at the same salt concentration. Plasticized PHB with 2.5% copper (II) sulfate inhibited both Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomona aeruginosa) bacteria, as determined by the bacterial inhibition halo. In addition, neat PHB films and PHB containing copper (II) sulfate did not show in vitro cytotoxicity in the L-929 cell line. Thus, plasticized PHB functionalized with copper (II) sulfate can be used as biodegradable antimicrobial flexible films for different applications.

Effect of Copper Sulphate Exposure on the Oxidative Stress, Gill Transcriptome and External Microbiota of Yellow Catfish, Pelteobagrus fulvidraco.

This study aimed to investigate the potential adverse effects of the practical application of copper sulfate on yellow catfish (Pelteobagrus fulvidraco) and to provide insights into the gill toxicity induced by copper sulphate. Yellow catfish were exposed to a conventional anthelmintic concentration of copper sulphate (0.7 mg/L) for seven days. Oxidative stress biomarkers, transcriptome, and external microbiota of gills were examined using enzymatic assays, RNA-sequencing, and 16S rDNA analysis, respectively. Copper sulphate exposure led to oxidative stress and immunosuppression in the gills, with increased levels of oxidative stress biomarkers and altered expression of immune-related differentially expressed genes (DEGs), such as IL-1β, IL4Rα, and CCL24. Key pathways involved in the response included cytokine-cytokine receptor interaction, NOD-like receptor signaling pathway, and Toll-like receptor signaling pathway. The 16S rDNA analysis revealed copper sulphate altered the diversity and composition of gill microbiota, as evidenced by a significant decrease in the abundance of Bacteroidotas and Bdellovibrionota and a significant increase in the abundance of Proteobacteria. Notably, a substantial 8.5-fold increase in the abundance of Plesiomonas was also observed at the genus level. Our findings demonstrated that copper sulphate induced oxidative stress, immunosuppression, and gill microflora dysbiosis in yellow catfish. These findings highlight the need for sustainable management practices and alternative therapeutic strategies in the aquaculture industry to mitigate the adverse effects of copper sulphate on fish and other aquatic organisms.

Synthesis of Surface Structures during Laser-Stimulated Evaporation of a Copper Sulfate Solution in Distilled Water

The methodology, technique, and results of studies of the formation of films on the glass surface during the irradiation of water solutions of copper sulfate with the laser radiation are presented. We used the nanosecond radiation of an yttrium-aluminum garnet laser with the generation wavelength λ = 1 .06 μm. The studies used solutions with different concentrations of copper sulfate. The structure of the films obtained in this case is compared with the structure of the films obtained as a result of drying the solutions without exposure to a laser radiation. The resulting films have both ordered and disordered structures. The characteristic dimensions of the structural elements of the films are 0.5–2 μm. The transmission of films in the 300–1200 nm spectral region is studied. In general, the resulting films are transparent in this area. Their transmission practically does not depend on the wavelength, but is different for different concentrations of the solution of copper sulfate.

Copper sulfate induces clinico-hematological, oxidative stress, serum biochemical and histopathological changes in freshwater fish rohu (Labeo rohita).

Despite being an essential trace element for numerous metabolic processes and micronutrients, copper (Cu) has induced adverse effects on the environment and public health due to its continuous and widespread use for the last several decades. The current study assessed the hematological and histopathological alterations in the freshwater fish (Labeo rohita) exposed to graded concentrations of copper sulfate. For this purpose, L. rohita fish (n = 72), weighing ~200-215 g, were randomly divided into four experimental groups and then exposed to acute doses of CuSO4, i.e., control, 0.28, 0.42, and 0.56 μgL-1. For comparative analysis of hematological and biochemical changes, blood/serum samples were obtained on 12, 24, and 36 days. Overall, the body weight of fish decreased with the time and dose of CuSO4; as the dose increases, body weight decreases. Dose and time-dependent results were observed in other parameters also. Results showed a significant increase in leukocytes, whereas red blood cells count, Hb, and Hct were significantly reduced in treated groups compared to the control. The mean corpuscular hemoglobin (MHC) and mean corpuscular hemoglobin concentration (MCHC) showed a non-significant decrease in treated groups compared to the control group. Serum biochemical parameters, including total proteins, albumin, and globulin, decreased significantly (p < 0.05). At the same time, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH), glucose, and cholesterol were significantly (p < 0.05) increased in the treated groups compared to the control group. Significantly (p < 0.05) increased levels of lipid peroxidation while decreased values of antioxidant enzymes, including superoxide dismutase (SOD), catalase (CAT), and reduced glutathione (RGSH) in the blood of fish were recorded. Histopathological examination of fish gills, liver, and kidneys showed inflammation and degenerative changes due to CuSO4 exposure. In the brain tissue, degenerative changes like neuron necrosis, intracellular edema, cytoplasmic vacuolization, and congestion were observed. In conclusion, the study indicates that exposure to copper sulfate, even in smaller concentrations, can cause adverse hematological and histopathological changes in L. rohita fish.

Differences in toxicity and accumulation of metal from copper oxide nanomaterials compared to copper sulphate in zebrafish embryos: Delayed hatching, the chorion barrier and physiological effects

The mechanisms of toxicity of engineered nanomaterials (ENMs) to the early life stages of freshwater fish, and the relative hazard compared to dissolved metals, is only partially understood. In the present study, zebrafish embryos were exposed to lethal concentrations of copper sulphate (CuSO4) or copper oxide (CuO) ENMs (primary size ∼15 nm), and then the sub-lethal effects investigated at the LC10 concentrations over 96 h. The 96 h-LC50 (mean ± 95% CI) for CuSO4 was 303 ± 14 µg Cu L−1 compared to 53 ± 9.9 mg L−1 of the whole material for CuO ENMs; with the ENMs being orders of magnitude less toxic than the metal salt. The EC50 for hatching success was 76 ± 11 µg Cu L−1 and 0.34 ± 0.78 mg L−1 for CuSO4 and CuO ENMs respectively. Failure to hatch was associated with bubbles and foam-looking perivitelline fluid (CuSO4), or particulate material smothering the chorion (CuO ENMs). In the sub-lethal exposures, about 42% of the total Cu as CuSO4 was internalised, as measured by Cu accumulation in the de-chorionated embryos, but for the ENMs exposures, nearly all (94%) of the total Cu was associated with chorion; indicating the chorion as an effective barrier to protect the embryo from the ENMs in the short term. Both forms of Cu exposure caused sodium (Na+) and calcium (Ca2+), but not magnesium (Mg2+), depletion from the embryos; and CuSO4 caused some inhibition of the sodium pump (Na+/K+-ATPase) activity. Both forms of Cu exposure caused some loss of total glutathione (tGSH) in the embryos, but without induction of superoxide dismutase (SOD) activity. In conclusion, CuSO4 was much more toxic than CuO ENMs to early life stage zebrafish, but there are subtle differences in the exposure and toxic mechanisms for each substance.

Effect of copper sulphate on Cryptocaryon irritans based on metabolome analysis.

Cryptocaryon irritans is one of the most harmful marine parasites in mariculture. Copper sulphate is often used to kill parasites and the influence of copper sulphate on the tomont stage of C. irritans was explored in this study. The results showed that excystment rate was not significantly affected when tomonts were exposed to 5 mg/L (76.7%) and 10 mg/L (78.9%) of copper sulphate for 3 h. However, excystment rate was significantly inhibited when exposed to 15 mg/L (33.3%) for 3 h and 5 mg/L (28.9%), 10 mg/L (33.3%) and 15 mg/L (33.3%) for 6 h. After treatment with high concentrations of copper sulphate, the interior of the tomonts was fuzzy under the microscope, and the division process could not be observed. Metabolomic results combined with preliminary transcriptome analysis results showed that the tomonts were induced to produce linoleate, riboflavin, inositol and other substances under the stress of Cu2+ , which affected the antioxidant mechanism of the body. Using MDA content determination and antioxidant enzyme activity analysis, copper sulphate was found to cause oxidative damage to tomonts by affecting the generation of metabolites, leading to the death of tomonts.

Effects of copper sulfate exposure on the nervous system of the Hirudo verbana leech

Copper is a significant environmental contaminant resulting from electronic waste and pesticide use. It is also a micronutrient that is essential for life because it is an enzyme cofactor. However, excess exposure to this heavy metal can lead to adverse physiologic effects. Prior studies have demonstrated neurotoxic effects of copper exposure on arthropods, mollusks, amphibians, and mammals, via mechanisms ranging from oxidative stress to changes in neurotransmitter levels. We focused on toxic effects of copper exposure on the nervous system of the Hirudo verbana leech, hypothesizing that copper exposure leads to neurobehavioral changes associated with structural changes to and proteomic changes within nerve ganglia. After exposing leeches to graded concentrations of copper sulfate, we performed neurobehavioral testing to measure their ability to ingest liver and record their movements in a 3-D printed pool. We dissected out nerve ganglia and examined them with light microscopy following hematoxylin and eosin staining. We also extracted, identified, and quantified proteins from the nerve ganglia using high performance liquid chromatography-mass spectrometry. We found that copper exposure was associated with neurobehavioral changes including food avoidance, diminished dark-seeking behavior, and decreased motility. Furthermore, we found histopathologic changes and proteomic alterations within nerve ganglia of copper-exposed leeches. These findings contribute to our understanding of potential mechanisms for nervous system damage with copper exposure. The results are concerning as they indicate that copper accumulation in the environment has tangible neurological consequences for exposed organisms.

Respiratory Response and Hemolymph Sugar Level of The Crab Barytelphusa gureini Exposed To Heavy Metals

To explore the respiratory and metabolic responses, the fresh water crabs Barytelphusa gureini, were exposed to sublethal concentrations (2.0 &amp; 2.25 µg/L) of cadmium chloride and copper sulphate respectively. Oxygen consumption and hemolymph sugar level of the animals were estimated to study the stress caused by these heavy metal toxicants. These animals after acclimatization to the laboratory conditions exposed for 0, 24, 48, 72 and 96 hrs to the toxicants. Total oxygen consumption was studied by Winkler’s method and the hemolymph sugar level was estimated by Anthrone method. In the present study, total oxygen consumption showed a gradual decline trend from 0 to 96 hrs in the experimental animals exposed to cadmium chloride, while the hemolymph sugar level recorded an elevation, with maximum increase at 96 hrs. These results showed that cadmium was found to be more toxic than copper metal.

Copper induces a downregulation of the Multidrug resistance protein 4 (MRP4) and Copper-transporting ATPase-RAN1 (RAN1) genes in red pine (Pinus resinosa) at low concentrations

ABSTRACT Copper is required in plant tissues at small concentrations for several physiological processes; however, excess metal can cause toxicity. The main objectives of this study were to (1) evaluate Pinus resinosa resistance to different concentrations of copper, and (2) assess changes induced by copper ions on gene expression. The targeted genes include the Multidrug resistance protein 4 (MRP4) and Copper-transporting ATPase-RAN1 (RAN1). P. resinosa seedlings were treated with different concentrations of copper sulphate and corresponding salt controls in growth chamber screening tests. These concentrations include 13, 130 mg and 1300 mg of copper per 1 kg of dry soil. Potassium sulfate and water were used as controls. The expression of MRP4 and RANI genes was assessed using RT-qPCR. All the genotypes tested were resistant to copper. There was a significant suppression of the MRP4 and RANI genes at the lowest concentration of copper (13 mg/kg) in comparison to the water control. Further increases in the copper concentrations (130 mg /kg and 1300 mg/kg) did not induce any significant change in gene expression. Overall, this study showed that P. resinosa is in general resistant to copper contaminants. However, copper ions affect gene expression, even at low concentrations.

Regional expansion and chemical control for invasive apple snails (Pomacea maculata) in Louisiana rice and crawfish production systems

Invasive apple snails, Pomacea maculata, have recently emerged as pests in the rice (Oryza sativa L.) and crawfish (Procambarus clarkii) production systems of southwest Louisiana. Their current distribution, expansion rates, and susceptibility to chemical control methods in these systems are not well known. This study examines the expansion of P. maculata in southwest Louisiana and evaluates chemical control via toxicity assays. The effects of chemical control were also assessed on the non-target species, Pr. clarkii. Westward expansion of P. maculata was recorded at ≈2 km per year and a northward expansion at a rate of ≈4 km per year with most new detections recorded south of established populations. P. maculata had a lower probability of being found in aquatic habitats with decreasing levels of dissolved oxygen. All concentrations of both liquid and crystal copper sulfate caused appreciable P. maculata mortality after 72 h, but control was inconsistent across treatments. Treatment with copper sulfate had no significant effect on Pr. clarkii mortality. Treatment of P. maculata egg masses with 5% and 10% crop oil solutions reduced the number of hatchlings by approximately 80% relative to non-treated controls. Future studies should attempt to find new factors associated with P. maculata occurrence in southwest Louisiana. More research should be conducted on the levels of copper sulfate that are ingested by P. maculata after initial exposure as well as new methods for crop oil applications on P. maculata egg masses.

Optimisation of culture conditions for a producer clone coexpressing arylsulfatase B and a formylglycine-generating enzyme in order to increase the yield of arylsulfatase B

Maroteaux—Lamy syndrome (mucopolysaccharidosis type VI) is an orphan genetic disease caused by mutations in the arylsulfatase B gene (ARSB), which encodes the lysosomal enzyme arylsulfatase B (ASB). The relevance of the study lies in the need of a Russian recombinant ASB product for patients with the disease in the Russian Federation. Previously, the authors have developed producer lines coexpressing the target ASB enzyme with an auxiliary formylglycine-generating enzyme (FGE), based on Chinese hamster ovary (CHO) cells. Further development of the recombinant ASB preparation places priority on increasing the enzyme yield. The aim of this study was to increase the productivity of producer clones by optimising the culture process and adding calcium chloride and copper sulfate to the culture medium. Materials and methods: a suspension-adapted CHO cell line was used. Monoclonal cell lines were developed using Cell Metric and ClonePix FL systems. The concentration of ASB in the culture liquid was determined using the enzyme-linked immunosorbent assay (ELISA). The authors analysed batch culture and/or fed-batch culture in media supplemented with various concentrations of copper sulfate and calcium chloride. Results: the combined addition of copper sulfate and calcium chloride at concentrations of 300 μM during batch culture of producer clones coexpressing ASB and FGE increases viability and specific productivity of the cells up to 4.58±1.62 pg/ (cell×day). The cultivation of the lead producer clone coexpressing ASB and FGE under fed-batch conditions for 12 days and the addition of copper sulfate to the growth medium at the concentration of 300 μM allow for increasing the yield of the active lysosomal enzyme, arylsulfatase B, to 420 mg/L. Conclusions: the cultivation of producer clones coexpressing ASB and FGE under fed-batch conditions with copper sulfate added to the medium significantly improves cell line growth properties and the ASB yield. This approach to the selection of culture conditions for producer cell lines can be applied to other enzymes of the sulfatase family.

Morphohistopathological alteration in the gills and central nervous system in Cyprinus carpio exposed to lethal concentration of copper sulfate

Copper Sulfate (CuSO4) is the most used in aquaculture as chemotherapeutic bath against bacterial, fungal and parasitic diseases but it is very toxic for fish so the goal of this study was to determine the lethal concentration of CuSO4 and evaluate it is toxicity in the gill and central nervous system (brain and spinal cord) in Cyprinus carpio. Fish exposed to 0, 2.5, 5 and 10 mg/L for 24 hours, each concentration with three replication each have six fish. The mortality rate was 100% at concentration 10 mg/L, which represented lethal concentration, while medium lethal concentration (LC50) was determined by Trevan method and it is 5mg/L. The fish with LC100 concentration exhibit abnormal respiration with gasping swimming, nervous sings with up down and stay at basin then die at 2-3 hours. The histopathological examination of the gills revealed circulatory disturbances, cellularity reaction, progressive and regressive alteration, this microscopic alteration was evaluated as semi-quantities analysis and there was variable significant (P≤0.05) in the pathological alteration and gill indexes between two treatments. In the brain and spinal cord, the lesions are represented by vasogenic edema, infiltration of inflammatory cells with atrophy in the neuronal body cells and hemorrhage. It is concluded from this study that the use of copper sulfate is within limited concentrations because increasing its concentration leads to fish toxicity, and it was observed that the gill tissue is more sensitive to toxicity than the central nervous system

Effect of Copper Sulfate On Hematological and Histological Parameters of Freshwater Fish Oreochromis niloticus at Various Sublethal Concentration

Heavy metals pollution is a great environmental problem in recent years throughout the world. Various activities such as domestic, anthropogenic activities, volcanic eruptions and industrial activities which increase their level of heavy metals concentration into the environment. Copper sulfate is used as an algaecide and fungicide in the fields of agriculture and aquaculture being discharged into water bodies and it can affect the aquatic organisms, especially fishes. The present study deals with the effect of copper sulfate on various hematological parameters of the experimental fish Oreochromis niloticus. Oreochromis niloticus is an important freshwater fish in commercial aquaculture. Fish is a significant food component of human food. Fish are the suitable bio-indicators of heavy metal contamination. Heavy metals are oxidative stress inducers in fish and can reflect aquatic contamination. The Objective of the present study was to analyze the hematological effects of heavy metal CuSO4 on the freshwater fish O.niloticus. The LC50 value of copper sulfate found to be 39.2 mg/L. The fish Oreochromis niloticus were experimented for the different sub lethal concentrations of 1/10, 1/20 and 1/30 of copper sulfate for the period of 30 days to get hematological changes. At the end of the experiment the result shows that the Red Blood Cell (RBC) count and the percentage of hemoglobin (Hb) were significantly decreased as the sub-lethal concentration of heavy metal Copper sulfate increased, while the level of WBC, MCV and MCH significantly increased. The effect of copper sulfate was observed by histopathological investigation of gill and liver of treated fish. The aim of present study is to investigate the hematological and histopathological effects of copper sulfate for the period of 30 days at various sublethal concentration in various tissues of the freshwater fish O. niloticus.Dietary data were collected in detail through face-to-face interview on tilapia O.niloticus consumption. Intake of fish (g) was computed. Statistical analyses were conducted using SPSS software for Windows and all tests were considered significant at p&lt;0:05.

Development of high copper concentration, low operating temperature, and environmentally friendly electroless copper plating using a copper ‐ glycerin complex solution

Few researchers have studied high metal ions concentration electroless plating solutions since increasing metal ions concentration shortens the solution life considerably. Nevertheless, as the required thickness of the electroless plating film reduces gradually, the limited solution life will not be a large problem. There are no detailed studies on the influence of high copper concentration electroless copper plating solution and their composition on the plating rate and decomposition time. Therefore, this paper explores the plating characteristics of high copper concentration from a copper‐glycerin complex solution. Taguchi's approach was used to optimize the plating rate and decomposition time based on an L18 orthogonal array with six main effect parameters and three levels. Main effect response tables and plots were employed to investigate the parameter influence. The significant factors of plating rate are temperature and pH, and the concentration of copper sulfate has much influence on the decomposition time. Temperature and copper sulfate concentration are the key factors to optimize the formulation of the plating solution. The optimized results were obtained at 0.18 M copper sulfate, 0.133 M formaldehyde, 0.36 M glycerin, 3.2 × 10−5 M 2,2’-dipyridyl, 29 °C, pH = 12.8. The copper concentration was more than four times higher than the conventional electroless copper plating solution, and the critical factors of high copper concentration in the electroless copper plating solution were revealed. It was found that copper formed 1:2 complexes with glycerin at a pH value of 12.8. In addition, the surface morphology and the uniformity of the plating layer were included as well.

Study of a system for creating a statistical model of the electroless plating of Cu-Ni-P alloys

ABSTRACT The electroless plating method is the most convenient for the metallisation of dielectrics. During this statistical study of the process, complex relationships were found between the composition of the electrolyte and the deposition regime. The complexity of this technology is an important multifactorial object of the study. An adequate linear regression model for electroless deposition of Cu-Ni-P alloy coatings was obtained by conducting a planned factorial experiment. It allows predicting the thickness of the electroless deposited alloy coating based on certain values of the input parameters (concentrations of copper sulphate, nickel sulphate and sodium hypophosphite) in the studied factor space, as well as further optimisation of the process.

Direct growth of hierarchical CoFe2O4 flower-like nanoflake arrays on Ni foam for high performance asymmetrical supercapacitor

• Tulip-like iron microstructure was electrodepositied on Ni foam from suspension of Fe 2 O 3 . • Fe@Ni foam was hydrothermally converted into CoFe 2 O 4 /Ni foam in solution of Co 2+ . • Hierarchical flower-like CoFe 2 O 4 nanoflake arrays exhibits excellent electrochemical properties. • ASC assembled with CoFe 2 O 4 /Ni foam and AC demonstrates capacitive performances. Flower-like cobalt ferrite (CoFe 2 O 4 ) nanflake arrays with high mass-loading was directly grown on Ni foam with a facile two-step hydrothermal method. First, hierarchical tulip-like Fe microstructure was electrodeposited on Ni foam from an alkaline Fe 2 O 3 suspension. Then, CoFe 2 O 4 flower-like CoFe 2 O 4 nanoflake arrays on Ni foam (CoFe 2 O 4 /Ni foam) was produced by heating Fe-modified Ni foam in cobalt nitrate aqueous solution containing low concentration of copper sulfate. The CoFe 2 O 4 /Ni foam was characterized with scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), energy dispersive X-Ray spectroscopy (EDS) and Brunauer-Emmett-Teller gas sorptometry measurements (BET). The electrochemical performances of CoFe 2 O 4 /Ni foam were tested with cyclic voltammetry (CV), galvanostastic charge/discharge technique (GCD) and electrochemical impedance spectroscopy (EIS). As capacitive electrode, CoFe 2 O 4 /Ni foam exhibits high areal capacity (9.7C cm −2 at 10 mA cm −2 ), good columbic efficiency (97.25% at 10 mA cm −2 ) and excellent cycling stability (capacity retention of 89.7% after 5000 GCD cycles at 20 mA cm −2 ). Asymmetric supercapacitor, assembled with CoFe 2 O 4 /Ni foam and activated carbon (AC) as positive and negative electrodes, respectively, exhibits high energy density of 6.01 W h m −2 at energy density of 50 W m −2 , indicating the promising application prospect of CoFe 2 O 4 /Ni foam in energy storage.