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By applying an aluminum coating to the copper-nickel alloy resistor, we successfully utilized air sintering. At 800 and 850°C, the alloy was sintered within an aluminum layer. This coating of aluminum serves as a protective layer. The copper-nickel was not oxidized as a result. After wet etching, the protective coating of aluminum was removed, leaving alloy resistors with Temperature Coefficient of Resistance (TCR) values of 417.86 ppm/°C. We produced an alloy paste using copper-nickel alloy (7:3) and then used screen printing to create thick-film alloy resistors. Therefore, it is feasible to create copper-nickel alloy resistors by air sintering. [ABSTRACT FROM AUTHOR]

Relevance. The need to study the features of aerogenic effects of the Norilsk industrial complex on the natural environment. Aim. To study the features of the aerogenic effects of the Norilsk industrial complex in the south-southwest zone at a distance of 40–60 km using lichens Cladonia rungeferina and Cetraria sp. Objects. Soil, lichens Cladonia rungeferina and Cetraria sp. Methods. Soil and lichen samples were taken 40–60 km south-southwest of the Norilsk Industrial district. Sampling was carried out according to the scheme of two profiles with a length of 14 and 20 km. The samples were analyzed using a set of methods consisting of X-ray fluorescence (S4 Pioneer Bruker AXS), atomic absorption methods (KVANT-2A, Julia-5K) and induction-coupled plasma mass spectrometry (ELEMENT-2) in the laboratory of the GIN RAS, Moscow. The concentration of Ti, V, Ni, Cr, Mn, Fe, Co, Cu, Zn, As, Se, Rb, Cd, Sb, Ba, La was determined. Results. The authors have obtained the data on the concentration of the 21 elements in soils and lichens. The paper demonstrates the calculation of distribution of elements in soil and lichens relative to the concentration in the upper part of the continental crust. The authors calculated the enrichment factor EF for Mn, Ni, Cu, Hg, Pb and estimated the distribution of this coefficient for both profiles. It is shown that the technogenic component of the aerogenic effect for Mn, Ni, Cu, Pb to the south-southwest of the Norilsk industrial complex at a distance of 40–60 km is practically absent. The increased values of the enrichment factor EF in lichens for Hg are explained by a combination of two factors – the constant presence of mercury in significant concentrations in ecosystems and tundra fires that took place in this zone in 2019–2020, which ultimately led to the re-deposition of Hg in the burnt areas.

Cobalt, nickel, copper, and tin nanosized particles were synthesized through a borohydride reduction method with a reducing agent of NaBH4. The reductive precipitation was carried out at room temperature and atmospheric pressure. The nanoparticle powders were synthesized from water solutions of sulfate salts. The obtained nanosized particles were investigated by scanning electron microscopy (SEM) and XRD analyses. The SEM micrographs showed the nanoparticles’ morphology and structure. The chemical elements’ distribution was determined by energy dispersive spectroscopy (EDS) analysis. The X-ray diffraction (XRD) analysis determined the phase composition and state (amorphous or crystalline). [ABSTRACT FROM AUTHOR]

Crystalline calcium carbonates (CCCs) are among the most widespread minerals on the Earth's surface and play a crucial role in the global carbon cycle, heavy metal sorption and incorporation. Among the numerous factors that influence the precipitation of CCCs from solution, the most determinant are the presence of additives in the mineral-forming medium, temperature, and crystallization time (aging time). The current work fills the gaps in the study of calcium carbonate crystallization from heavy metal (Me2+ = Co, Ni, Cu Fe)-containing solutions (Me2+/Ca 0.005–1.600) at different temperatures (3 and 23 °C) and aging times (21–158 days). The resulting precipitates were studied using optical and scanning electron microscopy, powder X-ray diffraction and energy-dispersive X-ray spectroscopy. Three crystalline calcium carbonates (synthetic analogues of calcite, aragonite and monohydrocalcite), as well as amorphous carbonate (AC), were found in the resulting precipitates. Temperature and aging time have a considerable effect on the phase composition, morphology and heavy metal content in CCCs. Low temperature (3 °C) and short aging times are generally favorable for the formation of monohydrocalcite and amorphous carbonate, while calcite tends to form at a higher temperature (23 °C) and in long-term experiments. Heavy metals can be incorporated into the calcite/monohydrocalcite crystal lattice in sufficient amounts, while aragonite can host a very small amount of Me2+ (or none). Calcite can concentrate Co (up to ~0.25 atoms per formula unit (apfu)) and Ni/Cu (up to ~0.05 apfu), while its Fe content is very close to the detection limits. Calcite precipitated at a higher Me2+/Ca ratio and temperature (23 °C) contains less Me2+ compared to calcite precipitated at a lower Me2+/Ca ratio and temperature (3 °C). Monohydrocalcite can host up to ~0.1 apfu of Co/Ni/Cu with no detectable preference for Me2+. The amount of Me2+ in monohydrocalcite decreases as aging time or temperature increases. It is worth noting that AC is the main carrier of heavy metals in the system being investigated and it should be considered the main host phase in heavy metal adsorption from aqueous solutions. The results obtained can be used to solve environmental issues and in mineral resource management. [ABSTRACT FROM AUTHOR]

Residual elements (Cu, Ni and Sn) of various contents have been added to a low-carbon steel to simulate the scenario of increased use of scrap during steel production. The samples were oxidized in air to represent reheating before hot rolling, using thermogravimetry analysis (TGA). Scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS) were employed to investigate the microstructure and the enrichments at the oxide/metal interface. Results showed the residual elements had an impact on the roughness of the scale/metal interface, internal Fe oxides formation, the amount of Ni&Cu enriched Fe phase and Cu&Sn enriched liquid phase at the interface, and the depth and spacing of the liquid phase penetrations along the grain boundaries. Thermodynamic simulation predicted the effect of residual elements on liquid phases formation at the interface, with good agreement between prediction and experimental results. The influence of residual elements on the oxidation rate was discussed. [ABSTRACT FROM AUTHOR]

Abiotic stresses, including drought and heavy metals, are detrimental to plant growth and development and enormously reduce agricultural yields. Plants may quickly change their transcriptome in response to various stressful conditions. Plants develop many defense mechanisms to respond to various stresses that can be classified into morphological, physiological, and biochemical responses. Polyphenol oxidases (PPOs) are one of the self-protective enzymes found in plants except for Arabidopsis. Currently, drought and heavy metals were applied exogenously to transgenic A. thaliana lines (transformed with Oryza sativa PPO promoter fused to the GUS reporter gene). The current study mainly focused on the systematic pathway by which plants respond to stressors. The aim of this study is to investigate the effect/expression of PPO and antioxidant defense system against abiotic stresses. A. thaliana was treated with different concentrations of polyethylene glycols. At 30% PEG, maximum fold induction (1.9) was seen after 12 h. Overall, various concentrations (5%, 20%, and 30%) induced PPO expression after 6, 12, and 24 h. Moreover, three different concentrations of Cu (50 µM, 100 µM, 200 µM) and Ni (50 µM, 100 µM, 200 µM) for 6, 12, and 24 h were also applied. It was observed that the expression profiling of the OsPPO promoter induced GUS gene expression in response to Cu and Ni treatments. The maximum fold induction (15.03) of GUS was observed in 100 µM of Cu after 24 h. In the case of Ni, maximum fold induction of (7.78) was observed at 100 µM after 24 h. So, both Cu and Ni showed a similar pattern of induction at 100 µM after 24 h. In conclusion, the efficiency of the PPOGUS promoter can be operated to assess the response of plants to various abiotic stimuli. [ABSTRACT FROM AUTHOR]

Copyright of Industrial Water Treatment is the property of CNOOC Tianjin Chemical Research & Design Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copper (Cu) is a perfect conductor, which is adapted for solar energy conversion and other advanced applications. In this work, we demonstrate the formation of Electrochemical Deposition (ELD) Cu layers directly on Ni barrier layers. The front contact consists of Ni and Cu layers. These double layers of metals help in reducing the series resistance of solar cells. ELD nickel layers of different thicknesses were deposited as a seed-layer at 58 °C on silicon substrate before electrolytic copper thickening. Further the Ni deposited are annealed at 400 °C, to obtain NiSi (Nickel Silicide), which lowers the contact resistivity between Ni and Si. The current density and deposition time of ELD Ni and Cu are investigated. Deposition current density was found to have a wide influence on the crystal orientation and the quality of the organization in the lattice. A continuous Cu film with thickness up to 57 μm is formed. The SEM images demonstrate the effect of electrodeposition parameters on the properties of Cu films. The rate of deposition and the film composition are studied. The effect deposition process and its characteristics are discussed. [ABSTRACT FROM AUTHOR]

The performance of La- or Ce-promoted NiCu-Al2O3 catalysts in the low-temperature (200 °C) hydrodeoxygenation (HDO) is assessed. Co-impregnation of the promoter with NiCu does not affect the bulk structure, although the catalytic activity of the Ce-promoted catalyst increases due to strong NiCu-Ce interactions. For sequential impregnation, the impregnation order for Ce improves either the HDO selectivity or the activity. For La, both sequentially impregnated catalysts exhibit an improved HDO selectivity, but a different activity. First impregnating La is especially interesting due to the catalysts enhanced stability after an initial deactivation period of 30 h TOS.

Plants that can accumulate metals to exceptionally high concentrations in their shoots are so-called hyper-accumulators. To further quantify potential interactions between Ni and Cu, the Alyssuem murale grown in soils with factorial additions of NiSO4·6 H2O (0, 50, 250, 500 and 750 mg kg-1 Ni = Ni-T0, 50, 250 and 750) and/or CuSO4·H2O (0, 50, 250 and 500 mg kg-1 Cu = Cu-T0, 50, 250 and 500) salts were investigated. The experiments were carried out in pots in a greenhouse under controlled temperature, light conditions and ambient humidity. The test plants for biomass production were harvested three times; 30, 60 and 100 days after germination. Ni and Cu concentrations in the digests were determined by flame atomic absorption. The results showed that by each different levels of Ni, the maximum amount of absorbed Ni was achieved at 50 mg kg-1 Cu concentration. Also, with elevation of Cu concentration, Ni uptake decreased. These results indicated that the Ni-T750 and Cu-T50 at the third time period had the maximum average of 1585 µg kg-1 and was significantly different from the other treatments. The statistical analysis indicated that by the increased Ni levels from zero to 50 mg kg-1 in soil, the performance of the plant dry matter was significantly declined at the all Cu levels. In addition, by the Cu-T50 in the soil, the dry matter amount at the all Ni levels were higher than that of Cu-T0, although the differences were not significant (p < 0.05).

We investigated the effect of Cu on the formation of reversed austenite in super martensitic stainless steel by using X-ray diffraction (XRD), a transmission electron microscope (TEM) and an energy-dispersive spectrometer (EDS). Our results showed that the microstructure of the steels comprised tempered martensite and diffused reversed austenite after the steels were quenched at 1050 °C and tempered at 550–750 °C. The volume fraction of reversed austenite in the steel with 3 wt.% of Cu (3Cu) was more than that with 1.5 wt.% of Cu (1.5Cu). The transmission electron microscope results revealed that the reversed austenite in 1.5Cu steel mainly had the shape of a thin strip, while that in 3Cu steel had a block shape. The nucleation points and degree of Ni enrichment of reversed austenite in 3Cu steel were higher than those in 1.5Cu steel. The reversed austenite was more likely to grow in ε-Cu enriched regions. Therefore, Cu can promote reversed austenite nucleation and growth. The mechanical properties of 3 Cu steel are obviously better than those of 1.5Cu steel when tempered at 550–650 °C. [ABSTRACT FROM AUTHOR]

In this paper, the influence of small additions of Cr, Mo, Cu, Ni, B, Ca, Zr, and Ce on the hot ductility of advanced high-strength steels (AHSS) has been reviewed. Most of these small additions have a positive effect in improving hot ductility on straightening during continuous casting operations and should be considered when problems with cracking in continuous casting are encountered. In many of these cases, the reason for these generally small but important improvements in hot ductility is not known with certainty, but the segregation of these elements to the austenite grain boundaries, strengthening the bonding, is often suggested. [ABSTRACT FROM AUTHOR]

This paper describes an experiment that made it possible to obtain helical multiwalled carbon nanotubes (НMWCNTs) with a diameter of 30-60 nm by pyrolysis of hydrocarbons and trapping the product with a liquid seal. For the purpose of comparative analysis, the paper also considers the synthesis of straight multiwalled carbon nanotubes (SMWCNTs). Such carbon nanotubes after preparation can be used in CJP 3D printing technology. All obtained materials are examined using the method of transmission electron microscopy. The paper considers the processes of synthesis of HMWCNTs and SMWCNTs. An assessment of the strength characteristics of 3D products from various composites based on them after discrete 3D printing and sintering is carried out. The conditions for the synthesis of carbon nanostructures by the pyrolytic method are described, methods for preparing synthesis products for their subsequent using in 3D printers of CJP, FDM, SLA, SLS technologies are developed, and the technology for preparing mechanical mixtures for 3D printers of CJP technology is developed. In addition, a technique for creating 3D products from composite materials is considered. The bending strength of 3D printed ceramics reinforced with carbon nanotubes is measured. The dependence of the bending strength of the obtained ceramics on the amount of MWCNTs in the composite is established. The resistance to mechanical destruction of composites (MWCNTs-Al2O3) obtained using helical and straight MWCNTs is studied. At the same time, it is shown that when using SMWNT, after the integrity of the composite is broken, the parts of the product do not crumble, but remain united even under load. [ABSTRACT FROM AUTHOR]

Cu-containing steels can suffer from hot shortness unless Ni is added to protect them but whether this problem also influences the straightening operation is not clear. Previous work on hot ductility has found that only when the tensile samples from Cu-containing steels are oxidised can any deleterious influence of copper be found. However, this paper shows that oxidation is not essential. It is more complex than that and, as Cu has been suggested for TRIP steels at levels up to 2.5% Cu to increase their strength and ductility, a greater understanding is required, both of hot shortness and cracking during straightening. The present paper explores the hot ductility behaviour of steels alloyed with Cu and Ni in the straightening temperature range, 700–1000 °C, when tested in air and in an argon atmosphere. Segregation of Cu to the sulphides and grain boundaries occurred allowing the formation of fine Cu2S particles at the austenite grain boundaries favouring intergranular failure and this was more pronounced under oxidising conditions and required strain. It was concluded that a Cu addition, as well as causing hot shortness at higher temperatures will also cause cracking problems in the straightening temperature range in the more sensitive to cracking grades of steel and although the problems are different they are nevertheless interrelated and provided there is sufficient Ni, both may be avoided. [ABSTRACT FROM AUTHOR]

Introduction: Asthma is a chronic inflammatory disease of the airways characterized by recurrent respiratory symptoms of dyspnea, wheezing, chest tightness, and cough.Aim: This study aims to investigate the concentrations of Cu, Zn, Mg, Mn, Fe, Cr, Ni, and Al in the serum of asthmatic patients.Materials and methods: An atomic absorption technique was used to determine the levels of trace elements. The study included sixty asthmatic patients and ninety healthy individuals as control group their ages ranging from 20 to 45 years.Results: We found a significant increase of the levels of copper, iron, and aluminum by 20%, 54%, and 47% (p0.05) between patients and control group.Conclusions: The increased level of Cu and Fe may reflect their potential role in the pathogenesis of asthma. Furthermore, the serum iron levels tend to be increased as a result of the inflammatory process that occurs in asthma. Low levels of Zn, Mg, and Mn may contribute to allergic diseases due to their role in the synthesis of certain antioxidants or to their effect on the immune system.

Plants that can accumulate metals to exceptionally high concentrations in their shoots are so-called hyperaccumulators. To further quantify potential interactions between Ni and Cu, the Alyssuem murale grown in soils with factorial additions of NiSO4·6 H2O (0, 50, 250, 500 and 750 mg kg-1 Ni-T0, 50, 250 and 750) and/or CuSO4·H2O (0, 50, 250 and 500 mg kg-1 Cu = Cu-T0, 50, 250 and 500) salts were investigated. The experiments were carried out in pots in a greenhouse under controlled temperature, light conditions and ambient humidity. The test plants for biomass production were harvested three times; 30, 60 and 100 days after germination. Ni and Cu concentrations in the digests were determined by flame atomic absorption. The results showed that by each different levels of Ni, the maximum amount of absorbed Ni was achieved at 50 mg kg-1 Cu concentration. Also, with elevation of Cu concentration, Ni uptake decreased. These results indicated that the Ni-T750 and Cu-T50 at the third time period had the maximum average of 1585 µg kg-1 and was significantly different from the other treatments. The statistical analysis indicated that by the increased Ni levels from zero to 50 mg kg-1 in soil, the performance of the plant dry matter was significantly declined at the all Cu levels. In addition, by the Cu-T50 in the soil, the dry matter amount at the all Ni levels were higher than that of Cu-T0, although the differences were not significant (p < 0.05). [ABSTRACT FROM AUTHOR]

M3(OH)2V2O7·nH2O ( M : Co, Ni, Cu, Zn) nanostructures were synthesized by a simple and economic chemical precipitation route. For Co and Ni compounds, very small (~9 nm), irregularly shaped and poor crystalline nanoparticles occurred, probably due to high tendency for complexing with ammonia molecules releasing from ammonium metavanadate. However, more crystalline Co compounds could be synthesized in high reactant concentrations, but not for Ni. Zn and Cu compounds are well crystallized in the hexagonal and monoclinic unit cell, respectively. Their shapes were nanoflake or nanoplate and their thickness were about 20 nm and 25 nm, respectively. Both have an average diameter of less than 500 nm. The chemical formulas determined were Co3V2O7(OH)2·2.8H2O, Ni3V2O7(OH)2·5.6H2O, Cu3V2O7(OH)2·2H2O and Zn3V2O7(OH)2·2.8H2O. The band gaps of samples were found in the range from 3.22 to 4.34 eV. Magnetic measurements show that all Co samples have a magnetic transition from ferromagnetic (FM) to paramagnetic (PM) around 300 K, on the ground that samples with FM characteristics and coupling at 5 K temperature turn into PM samples at room temperature. These results are important for large-scale synthesis of nanovanadate structures.

In the present study, the levels and probable public health risks of selected metals (Fe, Mn, Cu, Zn, Ni, Cd and Pb) in nine wheat flour samples collected from Amhara, Oromia, South region, and the Strategic Food Reserve Agency were determined using FAAS and compared with results of prior studies and critical level. The wet digestion method using 65 % HNO3 and 72 % HClO4 in 300°C for 3 h was used when preparing the sample. Validation of the optimised digestion method was assessed using the spiking method, and an acceptable percent recovery from all metals. The levels of Fe, Cu, Mn, Zn, Ni and Cd ranged between 8⋅5297 and 11⋅1535, 1⋅633 and 4⋅2346, 3⋅1875 and 8⋅5313, 2⋅3589 and 2⋅7719, 0⋅154 and 0⋅854, and 0⋅0411 and 0⋅216 mg/kg, respectively, for Ethiopian wheat flour, while the level of Fe, Cu, Mn, Zn, Ni, Cd and Pb were ranged between 8⋅0099 and 8⋅1089, 1⋅663 and 1⋅6691, 4⋅5625 and 4⋅6250, 2⋅3015 and 2⋅3072, 0⋅9423 and 1⋅1346, 0⋅1593 and 0⋅1606, and 0⋅13 and 0⋅1381 mg/kg, respectively, for imported wheat flour. However, Pb had a concentration of less than 0⋅043 mg/kg for Ethiopian wheat flour. Findings indicate that Ethiopian wheat is comparatively higher in Fe, Mn, Cu, Zn and Cd, but lower in Ni and Pb than imports. From the result of the study, it can be concluded that the level of heavy metals determined in this study was within the permissible limit, and no probable health risk because both the Hazard quotient (HQ) and the Hazard Index (HI) are found to be below 1⋅0 regarding study metals.

In this paper, the influence of small additions of Cr, Mo, Cu, Ni, B, Ca, Zr, and Ce on the hot ductility of advanced high-strength steels (AHSS) has been reviewed. Most of these small additions have a positive effect in improving hot ductility on straightening during continuous casting operations and should be considered when problems with cracking in continuous casting are encountered. In many of these cases, the reason for these generally small but important improvements in hot ductility is not known with certainty, but the segregation of these elements to the austenite grain boundaries, strengthening the bonding, is often suggested.

Theoretical photoionization cross-sections and angular distribution parameters for valence and subvalence shells of 3 d -elements from Sc to Zn are calculated with account for intrachannel and interchannel interactions for the energy region from threshold up to 400 eV. Many-electron effects were accounted for within the framework of RPAE (random phase approximation with exchange) method, which is extended for average terms of unfilled shells. Calculations demonstrate a decrease of σ(3 s) by approximately 25 %- 30 % for photon energies up to 24 Ry. and significant increase of σ(4s) for photon energies up tp 4 Ry and also a small decrease σ(3 p) relative to the HFS results of Yeh and Lindau, whereas the influence of correlations on σ(3 d) is negligible [ABSTRACT FROM AUTHOR]

[Display omitted] • In-depth analyses clarify the different selectivity over Ni and Cu catalysts. • DHMF desorption and further hydrogenation influence HMF hydrogenation selectivity. • High dielectric solvents enhance DHMF desorption and change selectivity over Ni. • Hydrogenation is less favorable at high temperatures due to thermodynamic nature. The development of heterogeneous catalysts for converting abundant biomass feedstocks to higher value products is one of the most challenges these days. 2,5-dihydroxymethylfuran (DHMF) and 2,5-dihydroxymethyltetrahydrofuran (DHMTHF), synthesized from HMF hydrogenation, serve as crucial precursors in various applications. Non-noble metal catalysts are particularly attractive for this reaction, given their affordability and impressive catalytic efficiency. This work unveils the origin of the unique selectivity over Ni and Cu through mechanistic investigation using density functional theory (DFT), thermodynamic and kinetic analyses. The results emphasize that temperature and solvent play a crucial role in altering the energetic stabilities of intermediates, thereby influencing the energetic span (δG), turnover frequency (TOF), and selectivity of the reaction. The theoretical results align well with experimental observations. At 373.15 K, the highest TOF values over Ni and Cu are predicted in the HMF-to-DHMTHF path (1.79 × 103h−1) and the HMF-to-DHMF path (4.01 × 105h−1), respectively, in gas phase—under low dielectric constant ε condition. In contrast, the highest TOF value for Ni is observed in the HMF-to-DHMF path under implicit water condition (ε = 78.4) at 298.15 K. Competitive DHMF desorption and further hydrogenation influence the reaction's selectivity. These insightful fundamental findings reveal key descriptors essential for designing new heterogeneous catalysts or enhancing existing ones, with the aim of potentially impacting biomass upgrading and other hydrogenation reactions. [ABSTRACT FROM AUTHOR]

• A fast and simple approach for Cu and Ni extraction from vegetable oils is proposed in this work. • An efficient extraction of the analytes was achieved by disruption of a three-component solution. • The three-component solutions were formed by mixing the oil with 1-octanol and HNO 3 solution. • GF AAS was employed for metals determination in the extracts. In this work, we propose a novel approach for extracting Cu and Ni from vegetable oils (which can be expanded to other metals). The method is based on the transference of the analytes to an aqueous acid phase due to the disruption of a three-component solution. The extraction was carried out in two steps. In the first step, a three-component solution was prepared comprising the sample, 1-octanol, and HNO 3 solution. Next, the homogeneous system was disrupted by adding 1.0 mL of deionized water, and two phases were formed. The aqueous extract deposited in the bottom of the flask was collected with a micropipette, and Cu and Ni were determined by graphite furnace atomic absorption spectrometry (GF AAS). The developed method presented limits of quantification (LOQ) of 0.25 and 0.17 ng g−1 for Cu and Ni, respectively, and was successfully applied in the analysis of eleven oil samples from different origins. [ABSTRACT FROM AUTHOR]

Pontechium maculatum, a facultative metallophyte, was collected from four ultramafic localities in Serbia and analysed in terms of micro- and macroelement accumulation. The aim of the study was to reveal trace element profiles and differences in uptake and translocation of heavy metals in populations growing under heavy metal stress. The concentrations of major and trace elements in soil samples (Ca, Mg, Fe, Mn, Ni, Pb, Cr, Zn, Cu, Co, Cd) and in plant tissues (Fe, Mn, Ni, Pb, Cr, Zn, Cu, Co, Cd) are presented. The results of our analysis indicate that P. maculatum efficiently absorbs Zn and Cr, while for most of the other elements accumulation levels fit in the range of values obtained for several other species from ultramafic localities on the Balkan Peninsula.

Cu-containing steels can suffer from hot shortness unless Ni is added to protect them but whether this problem also influences the straightening operation is not clear. Previous work on hot ductility has found that only when the tensile samples from Cu-containing steels are oxidised can any deleterious influence of copper be found. However, this paper shows that oxidation is not essential. It is more complex than that and, as Cu has been suggested for TRIP steels at levels up to 2.5% Cu to increase their strength and ductility, a greater understanding is required, both of hot shortness and cracking during straightening. The present paper explores the hot ductility behaviour of steels alloyed with Cu and Ni in the straightening temperature range, 700–1000 °C, when tested in air and in an argon atmosphere. Segregation of Cu to the sulphides and grain boundaries occurred allowing the formation of fine Cu2S particles at the austenite grain boundaries favouring intergranular failure and this was more pronounced under oxidising conditions and required strain. It was concluded that a Cu addition, as well as causing hot shortness at higher temperatures will also cause cracking problems in the straightening temperature range in the more sensitive to cracking grades of steel and although the problems are different they are nevertheless interrelated and provided there is sufficient Ni, both may be avoided.

Enteric fever caused by Salmonella typhi has been the most crucial health issue in rural people, especially in Southeast Asia and Africa. Another disease, Salmonellosis , caused by a large group of bacteria of the genus Salmonella , cause substantial economic loss resulting from mortality and morbidity. Higher concentration and repeated use of antibiotics to treat these diseases will likely develop antibiotic resistance among the microbes. The nanoparticle has good penetration power and can kill microbes. Combining two strategies by using nanoparticles with antibiotics kills microbes and reduces the chances of the development of antibiotics resistance. Silver, Nickel, Copper, and Zinc oxide Nanoparticles were chemically synthesized and characterized in this study. Silver nanoparticles at a concentration of 10 µg/ml inhibit all the strains under study. In comparison, silver nanoparticles (16.90 µg/ml), Nickel nanoparticles (83 µg ml−1), Copper nanoparticles (249 µg ml−1), and Zinc oxide (1614 µg ml−1) along with 50 µg/ml cefixime gave maximum zone of inhibition of 35 mm, 19 mm, 31 mm and 23 mm respectively. The antimicrobial assay showed that silver nanoparticles presented good antibacterial performance against all multi-drug-resistant pathogenic Salmonella sp alone as well as in combinations. The present study proved that silver nanoparticles at the lowest concentration along with cefixime could be a possible alternative to control the multi-drug-resistant pathogens. [ABSTRACT FROM AUTHOR]

Heavy metal pollution is a global problem although its sources and trends differ by region and time. To data, no published research has reported heavy metal pollution in global rivers and lakes. This study reviewed past sampling data across six continents from 1970 to 2018 and analyzed the trends and sources of 10 heavy metal species in sediments from 289 rivers and 133 lakes. Collectively, river sediments showed increasing trends in Cd, Cr, Ni, Mn, and Co and decreasing trends in Hg, indicating that rivers acted as a sink for the former and a source for the latter. Lake sediments showed increasing trends in Pb, Hg, Cr, and Mn, and decreasing trends in Cd, Zn, and As, indicating that lakes acted as a sink for the former and a source for the latter. Due to difference in natural backgrounds and development stage in continents, mean metal concentrations were generally higher in Europe and North America than in Africa, Asia, and South America. Principal component analysis showed that main metal source was mining and manufacturing from the 1970s to 1990s and domestic waste discharge from the 2000s to 2010s. Metal sources in sediments differed greatly by continent, with rock weathering dominant in Africa, mining and manufacturing dominant in North America, and domestic waste discharge dominant in Asia and Europe. Global trends in sediment metal loads and pollution-control measures suggest that the implementation of rigorous standards on metal emissions, limitations on metal concentrations in manufactured products, and the pretreatment of metal-contaminated waste have been effective at controlling heavy metal pollution in rivers and lakes. Thus, these efforts should be extended globally. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The thick-film conductor pastes that are applied most widely are Ag and Cu due to their high conductivity. Ag paste can be sintered in air to have high conductivity, but its disadvantage is the overly high cost. Contrarily, although Cu thick paste is not expensive in terms of materials, Cu thick-film paste must be sintered in a reducing atmosphere to obtain high conductivity, which leads to high processing costs. A novel method for fabricating the base metal electrode Cu in an air atmosphere for high-temperature firing was successfully developed based on thick-film screen-printing Al pastes utilizing a reduction-oxidation substitution reaction. To make an excellent Cu electrode that can be substituted for a thick-film Al electrode, Al paste with high solid content, a large Al powder particle size, a CuSO4 solution with low pH, high temperature, and proper soaking time are all positive parameters. The first thick-film screen-printing Cu electrode with high conductivity (> 10−6 Ω), which is comparable with a thick-film Ag electrode, was successfully fabricated in air firing instead of reducing atmosphere firing. [ABSTRACT FROM AUTHOR]

Thermal management of Al composites is a crucial issue to keep the promising performance and excellent reliability of the devices. We revealed a novel method to enhance the surface property of graphite flakes (GF) with Cu and Ni coatings by chemical plating way. Taking advantage of Cu and Ni co-doped GF and silicon powders, the GF@Cu@Ni/Si/Al composites were fabricated by vacuum pressure infiltration method. The GF@Cu-30@Ni-10 composites revealed about 2 times larger TC (474.4 W/m·K) and lower CTE 6.22 ppm/K than neat Al. Our strategy for highly TC offers not only the advanced process for dispersing reinforcements but also an extremely simple way for the anisotropic composites with high TC and low CTE. [ABSTRACT FROM AUTHOR]

Purpose: Mobility of representative heavy metals during the anaerobic digestion of sludge under mesophilic and thermophilic conditions was compared. Methods: The exchangeable, carbonates (F1), Fe and Mn oxides (F2), organic matter, sulfides (F3) and residual (F4) fractions of heavy metals in sludge were fractionated by the modified BCR procedure. Inductively coupled plasma-optical emission spectrometry (ICP-OES) was used to determine the Cu, Ni and Zn concentrations of the different fractions. Results: The mobile fraction (F1, F2 and F3) of Cu, Ni and Zn increased with the progression of the anaerobic digestion process. The mobile fraction of Cu, Ni and Zn under thermophilic conditions was greater than under mesophilic conditions. The mobile fraction of Cu, Ni and Zn also increased with the increase of the ammonia concentration, especially under mesophilic conditions. The acid-soluble fraction levels of the studied metals were ranked as follows Ni > Zn > Cu. Conclusions: The mobility of the representative heavy metals (Cu, Ni and Zn) during the anaerobic digested of sludge under thermophilic conditions was greater than under mesophilic conditions. These results show that more attention to the negative impacts of heavy metals present in anaerobically digested sludge under thermophilic conditions before land applying. [ABSTRACT FROM AUTHOR]

Poultry litter biochar (PLB) has great potential for carbon (C) sequestration, which has been confirmed in the previous study. The promising potential of PLB for nutrient preservation and contaminant immobilization, however, has not been well studied. A multi-contaminated soil, mainly contaminated by chrome (Cr), copper (Cu), nickel (Ni), and zinc (Zn) was selected for this short-term incubation study. The purpose of this study was to evaluate the effects of PLB after incubation on the release of available nutrients (phosphorus, P; potassium, K; calcium, Ca; magnesium, Mg) and on the solubility of Cr, Cu, Ni, and Zn. The results of 56-day incubation indicated that high-temperature pyrolysis PLB (>400 °C) has great potential to raise soil pH, electrical conductivity (EC), and concentrations of P, K, and Mg; however, maintenance of lower Cr and Cu concentrations and a decline in Ni and Zn concentrations were also observed. The solubility of Cr, Cu, and Ni increased with dissolved organic carbon (DOC) increased, suggesting co-mobilization occurred. The solubility of Zn decreased with increased pH, suggesting adsorption by PLB and/or soil. We recommend the use of 5% high temperature pyrolysis PLB (500 and 600 °C) as a gentle soil amendment to achieve C sequestration, provide available nutrients, maintain low available concentrations of Cr/Cu, and reduce Ni/Zn availability.

The study is devoted to X-ray fluorescence spectroscopy (XRF) features of micro- and nanosized powder mixtures of copper and nickel. XRF is a high accuracy method that allows for both qualitative and quantitative analysis. However, the XRF measurement error due to the size of the studied particles is not usually taken into account, which limits the use of the method in some cases, such as analysis of Ni-Cu mixtures and coatings. In this paper, a method for obtaining copper and nickel nanoparticles was investigated, and the XRF of powder compositions was considered in detail. The initial micro- and nanoparticles of copper and nickel were studied in detail using SEM, TEM, XRD, and EDX. Based on experimental data, calibration curves for copper-nickel powder compositions of various sizes were developed. According to the results, it was experimentally established that the calibration curves constructed for nanoscale and microscale powders differ significantly. The presented approach can be expanded for other metals and particle sizes.

In the present work, Cu and Ni nanofluids were synthesized using the pulsed wire evaporation (PWE) method in the different aqueous medias, namely (ethanol and ethylene glycol), and the effects of the aqueous media on the dispersion state, stability, and particle size of nanoparticles were studied. The size and morphology of synthesized nano-particles were investigated by transmission electron microscopy (TEM). Also, the dispersion stability of the nanofluids was evaluated by turbiscan analysis. The TEM results showed that the nano-particles were spherical in shape, and the average particle size was below 100 nm. The average particle size of the Cu nano-particles was smaller than that of Ni, which was attributed to a difference in the specific sublimation energy of the elements. Moreover, ethylene glycol (EG) exhibited higher suspension stability than ethanol. Finally, the dispersion stability of Cu@EG displayed the highest value due to lower particle size and greater viscosity.

Catalytic enantioselective conjugate addition (ECA) reactions with readily accessible and stereochemically defined E‐, Z‐, di‐ and trisubstituted alkenyl aluminum compounds are disclosed. Transformations are promoted by various NHC‐copper catalysts (NHC=N‐heterocyclic carbene), which are derived from enantiomerically pure sulfonate imidazolinium salts. The desired products were obtained in up to 89% yield and >99:1 e.r.; the alkenyl moiety was transferred with complete retention of its stereochemical identity in all instances. The scope and limitations of the approach, key mechanistic attributes, and representative functionalization are presented as well. [ABSTRACT FROM AUTHOR]

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• The simple method of "charge enhanced dry impregnation" can be effectively applied to a difficult-to-impregnate support, SBA-15 (silica). • CEDI yields smaller particles than typical preparations of incipient wetness; particles become ultra-small (<2 nm) with a washing step. • CEDI of two precursors (co-CEDI) can be used to synthesize very small, homogeneously alloyed supported nanoparticles. • In general CEDI over SBA-15 is quite similar to CEDI over amorphous silica. Charge enhanced dry impregnation (CEDI) is a method to synthesize supported metal nanoparticles which combines the simplicity of incipient wetness impregnation with the small particle size obtained from electrostatic adsorption of metal precursors onto the oxide support. We have explored the utility of CEDI by applying it to a difficult to impregnate support – a largely one dimensional porous SBA-15 silica. Monometallic (Pt, Pd, Co, Ni, and Cu) catalysts at multiple metal loadings (1–20 wt%) as well as their bimetallic pairs were supported on mesoporous SBA-15 and characterized by high sensitivity powder XRD and in select formulations, with aberration-corrected z-contrast STEM imaging. CEDI applied to SBA-15 without washing is more effective than dry impregnation (DI) of SBA-15. Compared to amorphous silica, CEDI of SBA-15 without washing gives larger particles at lower metal loadings, while at higher metal loadings, the pores of the SBA-15 help render the particle size smaller than amorphous silica. CEDI without washing of SBA-15 with nitrate salts gives somewhat smaller particles than CEDI with chloride salts. CEDI with washing to remove residual counterions of the metal salt typically gives nanoparticles smaller than 2 nm. The smallest particles are always obtained when the counterion is removed by washing, or when a hydroxide salt is employed; ultrasmall particles are obtained without washing in this case. [ABSTRACT FROM AUTHOR]

In the present study, oxidative coupling of thiols was carried out using immobilized Cu, Ni and Pd complexes on SBA-15 mesostructured as novel and green heterogeneous catalysts under mild reaction conditions. These supported complexes were characterized by FT-IR, XRD, TEM, TGA, EDX, ICP and BET techniques. These nanohybrid robust catalysts have outstanding advantages such as facile synthesis, use of green medium, high surface area, easy separation and workup, excellent reused for several consecutive cycles without noticeable change in its catalytic activity, and short reaction time. [ABSTRACT FROM AUTHOR]

Ti-6Al-4V, an advanced engineering material is difficult-to-machine using conventional machining process due to its high strength. It has properties like low weight ratio, outstanding corrosion resistance along with high level of reliable performance in micro components. Micro-electro-discharge machining (Micro-EDM), a popular nontraditional machining process has been identified as the most appropriate machining process for such material. In this paper, the effect of various conducting powders such as copper, nickel and cobalt with different concentrations are mixed with deionized water dielectric, on various responses such as material removal rate (MRR), tool wear rate (TWR), overcut (OC) and taper has been presented. Also, principal component analysis (PCA) has been applied to select the optimal parametric combination of micro-EDM process to achieve optimal values of MRR, TWR, OC and taper during micro-through hole machining. The optimal process parametric setting obtained from the proposed approach is peak current (Ip) of 1.5 A and cobalt (Co) powder concentration of 4 g/L so as to obtain the desired responses. It is also observed from the SEM image that the machined profile and surface topography obtained through the multi-objective optimal parametric combination based on PCA is quite satisfactory and can be applied to achieve geometrically more accurate micro-through holes on Ti-6Al-4V. [ABSTRACT FROM AUTHOR]

To fundamentally understand the solid–liquid interdiffusion joining processes between a Cu electrode and Co and Ni barrier layers using a Ga solder, the interfacial reactions in the Cu/Ga, Co/Ga, Ni/Ga, Cu/Ga/Co and Cu/Ga/Ni samples have been systematically examined. The reaction phases at the Cu/Ga interface in the Cu/Ga, Cu/Ga/Co and Cu/Ga/Ni samples reacted at 200°C, 350°C and 500°C are all the same, and are γ3-Cu9Ga4 and CuGa2, γ2-Cu9Ga4 and γ1-Cu9Ga4 respectively. No Co/Ga interfacial reaction phase was found in either the Co/Ga or Cu/Ga/Co samples reacted at 200°C, and the reaction phase is CoGa3 when reacted at 350°C and 500°C. The reaction phase in the Ni/Ga couples reacted at 200°C and 350°C is the Ni3Ga7 phase while it is Ni2Ga3 at 500°C. In the Cu/Ga/Ni samples, no Ni/Ga interfacial reaction phase is observed at 200°C, and the Ni3Ga7 and Ni2Ga3 phases formed at 350°C and 500°C have 8.5 at.%Cu and 14.0 at.%Cu solubilities. The growth rates of the reaction phases have been determined, and the Ga consumption rates in the Cu/Ga/Co and Cu/Ga/Ni samples at 200°C, 350°C and 500°C were calculated. It is observed that the consumption rates increase with the square root of the reaction time, and the consumption rate constants are 39.2 μm/h0.5 and 77.3 μm/h0.5, respectively. [ABSTRACT FROM AUTHOR]

The development of highly efficient and green catalyst for the one-pot synthesis of 5-substituted tetrazole and polyhydroquinoline derivatives is an extremely important and ground challenging area in organic chemistry. In this study, two catalysts were prepared by the immobilization of Ni and Cu on ordered mesoporous silica (SBA-15) coated with glycine. The proposed catalysts were characterized by FT-IR, XRD, BET, TGA, EDX, and ICP-OES studies and were successfully applied in the synthesis of 5-substituted tetrazoles and polyhydroquinoline derivatives. This designed protocol offers several advantages including the use of commercially available and inexpensive materials, simple procedure, short reaction times, high yield, and easily separable and reusable catalyst. Image 1 • Two green and novel SBA-15@Glycine-M (M = Ni and Cu) catalyst were prepared. • These catalysts can be used as an efficient nanocatalyst in synthesis of 5-substituted tetrazoles and polyhydroquinoline. [ABSTRACT FROM AUTHOR]

Abstract In this paper, a systematic growth behavior of Cu, Ni and Cu/Ni microwire arrays in porous silicon (PSi) templates is presented. After preparation of PSi templates via anodizing in HF solution, such microwires are successfully grown into PSi templates by electrodeposition method. Systematic scanning electron microscopy (SEM) imaging reveals that Cu seed nucleation occurs at the bottom and Ni seed nucleation starts on the wall of the silicon pores. The different growth models are explained according to the observed diffusion coefficients of ionic elements in electrodeposition baths. X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX) were used to further observe the structural characteristics of the grown microwires. We believe that this work can be used in developing microwires with desired structural characteristics. Highlights • Deposition of Cu, Ni, and Cu/Ni microwires within porous Si was investigated • Nucleation of Cu seed occurred at the bottom of silicone pores • Nucleation of Ni seed started on the wall of silicone pores [ABSTRACT FROM AUTHOR]

Highlights • A new biosorbent for solid phase extraction is recommended. • Coprinus silvaticus was immobilized on multiwalled carbon nanotube. • Cu(II), Ni(II) and Pb(II) were preconcentrated. • The method was validated and applied to real samples. Abstract Preconcentrations of Cu(II), Ni(II) and Pb(II) ions by using Coprinus silvaticus immobilized multiwalled carbon nanotube (MWCNT) were investigated. Effects of important parameters on preconcentration procedure were examined. The best pH values of for Cu(II), Ni(II) and Pb(II) were found to be 6.0, 6.0 and 4.0, respectively. Flow rate of sample solution was 2.0 mL min−1, while desorption was achieved at 1.0 mL min−1 flow rate. Preconcentration factors were achieved as 60 for Cu(II), Ni(II) and 70 for Pb(II) (by dividing initial sample volume to final volume). LODs were calculated as 0.014, 0.016 and 0.093 ng mL−1, respectively for Cu(II), Ni(II) and Pb(II). Accuracy of the method was checked by applying to certified reference samples. Inductively coupled plasma optical emission spectrometer (ICP OES) was employed for measurements of Cu(II), Ni(II) and Pb(II) in digested baby food samples. [ABSTRACT FROM AUTHOR]