Increase In Cu Research Articles

Influence of Cu/Mg ratio and content on heat-resistance of Al–Cu–Mg alloys

Heat-resistant Al alloys used in such as aerospace, transportation fields are attracting more and more attention in recent years. Within Al alloy families, Al–Cu–Mg alloys have shown promising heat resistance properties. This work aims to investigate the influence of Cu/Mg ratio and content on the heat resistance of Al–Cu–Mg alloys, based on alloys of Al–4.5Cu–2.5 Mg (referred to as alloy A), Al–4.0Cu–2.2 Mg (alloy B) and Al–4.5Cu–1.6 Mg (alloy C). The alloys A and B possessed approximate Cu/Mg ratio, and they also exhibited nearly identical hardness retention rate during exposure at 200 °C. After 200 h, the rate is ∼75 %, though alloy A showed higher hardness (105 vs. 102 HBW) due to higher Cu, Mg content. In contrast, alloy C with a higher Cu/Mg ratio was less heat-resistant, with hardness retention rate of ∼70.5 % after 200 h exposure. Nano-sized S′(Al2CuMg) precipitate was main strengthening phase for the three alloys. Also, micron and submicron Al2CuMg particles could be formed with increase of Cu and Mg contents, which contributed a lot to yield strength for T6 heat-treated alloys, but slight contribution after exposure at 200 °C for 200 h. The degradation of mechanical properties during heat exposure can be attributed to the transformation and coarsening of S′ precipitates. In alloys with lower Cu/Mg ratio, there was excess Mg dissolved in Al matrix, which reduced Cu solubility in α-Al, and then slowed diffusion flux of Cu element, thus inhibited coarsening of Al2CuMg phase.

In Situ Electrochemistry of Formate on Cu Thin Films Using ATR-FTIR Spectroscopy and X-ray Photoelectron Spectroscopy.

Formate (HCOO-) is the most dominant intermediate identified during carbon dioxide electrochemical reduction (CO2ER). While previous studies showed that copper (Cu)-based materials that include Cu(0), Cu2O, and CuO are ideal catalysts for CO2ER, challenges to scalability stem from low selectivity and undesirable products in the -1.0-1.0 V range. There are few studies on the binding mechanism of intermediates and products for these systems as well as on changes to surface sites upon applying potential. Here, we use an in situ approach to study the redox surface chemistry of formate on Cu thin films deposited on Si wafers using a VeeMAX III spectroelectrochemical (SEC) cell compatible with attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). Spectra for surface species were collected in real time as a function of applied potential during cyclic voltammetry (CV) experiments. Results showed the reproducibility of CV curves on freshly prepared Cu/Si wafers with relatively high signal-to-noise ATR-FTIR absorbance features of surface species during these electrochemical experiments. The oxidation reaction of HCOO- to bicarbonate (HCO3-) was observed using ATR-FTIR at a voltage of 0.27 V. Samples were then subjected to reduction in the CV, and the aqueous phase products below the detection limit of the SEC-ATR-FTIR were identified using ion chromatography (IC). We report the formation of glycolate (H3C2O3-) and glyoxylate (HC2O3-) with trace amounts of oxalate (C2O42-), indicating that C-C coupling reactions proceed in these systems. Changes to the oxidation state of surface Cu were measured using X-ray photoelectron spectroscopy, which showed a reduction in Cu(0) and an increase in Cu(OH)2, indicating surface oxidation.

Novel insights for simultaneous NOx and CO Removal: Cu+-Sm3+-Ov-Ti4+ asymmetric active site promoting NH3-SCR coupled with CO oxidation reaction

Ammonia selective catalytic reduction (NH3-SCR) coupled with CO oxidation is a promising approach for simultaneous removal of NOx and CO. However, finding a bifunctional catalyst that can effectively facilitate both reactions remains a significant challenge. This study investigates the enhancing effect of Cu+-Sm3+-Ov-Ti4+ asymmetric active sites on the oxidation reaction of NH3-SCR coupled with CO oxidation. The traditional Cu/TiO2 catalyst can achieve a maximum NOx conversion of 75 % at 225 °C, while the CuSmOTi catalyst can achieve 100 % NOx conversion at 200 °C. The successful construction of the asymmetric active site leads to an increase in Cu+ content, producing abundant oxygen vacancies, accelerating the redox cycle in the reaction process, and improving the adsorption capacity of CO. Additionally, compared with the 8.4 % Cu dispersion on the Cu/TiO2 catalyst, the Cu dispersion on the SmCuOTi catalyst is as high as 75.0 %, which improves the reduction performance of the catalyst. A large number of Lewis acid sites optimize the activation and adsorption of the catalyst to the reactants. In-situ DRIFTS analysis indicates that the NH3-SCR reaction on the CuSmOTi catalyst primarily follows the (E-R) mechanism, while CO oxidation follows the (MvK) mechanism. Moreover, the formation of a significant number of amide intermediates during the reaction process enhances the N2 selectivity. These findings present a novel concept of utilizing asymmetric active sites in NH3-SCR coupled with CO oxidation reactions, provides valuable insights for achieving the complete removal of nitrogen oxides and carbon monoxide in the case of “0″ by-products.

Hyperthermal-driven anoxia and reduced productivity in the aftermath of the Permian-Triassic mass extinction: a case study from Western Canada

Introduction: The eruption of the Siberian Traps near the Permian-Triassic boundary (PTB) resulted in the rapid input of vast amounts of CO2 into the atmosphere and the subsequent development of a hothouse climate across much of the Early Triassic. The distribution of environmental stresses led to a complex recovery as survivors navigated high SSTs in shallow settings and an expanded OMZ that impinged upon the continental shelves. The Ursula Creek section of western British Columbia preserves a complete Lower-lowermost Middle Triassic sedimentary record of deep-water facies and provides a means to examine how offshore oceanic conditions varied along the western continental margin of Pangaea across the PTB and the entire Permian-Triassic recovery interval.Methods: A total of 204 samples were collected from the uppermost Permian Fantasque Formation, the Griesbachian—Dienerian Grayling Formation and the Smithian—Anisian Toad Formation and analyzed for major, minor, and trace elements in addition to %TOC contents.Results: Anoxic to euxinic conditions were persistent during deposition of most of the study interval based on lithologic indicators (finely-laminated siltstone that lacks trace fossils and a benthic fauna) and elevated Mo, U, and V enrichment factors (EFs). Ba, Cu, Ni, P, and Zn EFs indicate dampened productivity (EFs <1) across the much of the Early Triassic that was the result of weakened upwelling during a global hothouse interval. An increase in Cu, Ni, P, and Zn enrichment factors during the Anisian track a decline in global temperatures and the reestablishment of coastal upwelling as global thermal gradients and wind speeds increased.Discussion: The results of this study point to the persistence of hyperthermal events and associated environmental stressors and underscores the urgency of curbing modern greenhouse gas emissions to prevent Earth from tipping into a hothouse state.

Strength, leaching characteristics and microstructure of CGF+P all-solid-waste binder solidification/stabilization Cu(Ⅱ) contaminated soil

Utilizing solid waste-based binder to solidify/stabilize (S/S) heavy metal contaminated soils is a sustainable approach. This paper implemented microscopic tests on Cu(II)-doped paste and macro-microscopic tests on S/S Cu(II) contaminated pure clay-particles soil (P-CS), pure silt-particles soil (P-ST), pure sand-particles soil (P-SD), and their mixed soil (CSSM), respectively, with CGF+P all-solid-waste binders (abbreviated as CGF+P binders) composed of calcium carbide residue (CCR), ground granulated blast furnace slag (GGBS), fly ash (FA), and phosphogypsum (PG). The results showed that the clay-minerals in soil determine the S/S efficiency, and Cu(II) threshold content exist in the presence of clay-minerals and absent without clay-minerals. The strength of P-CS and CSSM containing clay-minerals first increased and then decreased with the increase of Cu(II) content, while the leached Cu(Ⅱ) were lower than 2 mg/kg. The strength of P-ST and P-SD without clay-minerals decreased gradually, and the leached Cu(Ⅱ) concentration far higher than 2 mg/kg. Cu(II) ions are immobilized by CGF+P paste and clay-minerals in soil. The S/S mechanism of Cu(II) by CGF+P binders rely on precipitation, adsorption, encapsulation, chemical compound, and ion exchange, and the immobilized mechanism of Cu(II) by clay-minerals through electrostatic attraction, ion exchange, and physical adsorption. However, the binder paste and clay-minerals have the immobilization capacity on Cu(II) ions, is related to the component of the binder and the type of clay-minerals, respectively. The findings provided useful reference for the design and development of solid waste-based binders suitable for S/S heavy metal contaminated soils.

Immunolabelling perturbs the endogenous and antibody-conjugated elemental concentrations during immuno-mass spectrometry imaging

Immuno-mass spectrometry imaging uses lanthanide-conjugated antibodies to spatially quantify biomolecules via laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). The multi-element capabilities allow for highly multiplexed analyses that may include both conjugated antibodies and endogenous metals to reveal relationships between disease and chemical composition. Sample handling is known to perturb the composition of the endogenous elements, but there has been little investigation into the effects of immunolabelling and coverslipping. Here, we used cryofixed muscle sections to examine the impact of immunolabelling steps on the concentrations of a Gd-conjugated anti-dystrophin primary antibody, and the endogenous metals Cu and Zn. Primary antibody incubation resulted in a decrease in Zn, and an increase in Cu. Zn was removed from the cytoplasm where it was hypothesised to be more labile, whereas concentrated locations of Zn remained in the cell membrane in all samples that underwent the immunostaining process. Cu increased in concentration and was found mostly in the cell membrane. The concentration of the Gd-conjugated antibody when compared to the standard air-dried sample was not significantly different when coverslipped using an organic mounting medium, whereas use of an aqueous mounting medium significantly reduced the concentration of Gd. These results build on the knowledge of how certain sample handling techniques change elemental concentrations and distributions in tissue sections. Immunolabelling steps impact the concentration of endogenous elements, and separate histological sections are required for the quantitative analysis of endogenous elements and biomolecules. Additionally, coverslipping tissue sections for complementary immunohistochemical/immunofluorescent imaging may compromise the integrity of the elemental label, and organic mounting media are recommended over aqueous mounting media.Graphical

Improvements in the physicochemical and electrical characteristics of BaO nanoparticles by Cu doping for electronic device applications

This work demonstrated the effects of Cu2+ ion doping on the morphological, structural, vibrational, optical, dielectric, and electrical characteristics of barium oxide (BaO) nanoparticles. The XRD analysis revealed the high purity and crystallinity of the prepared Cu doped BaO samples. The crystallite size of the Cu doped BaO nanoparticles was in the range of 6.51 nm to 8.49 nm and increased as the Cu2+ increased. The SEM micrographs revealed the irregular and spongy like morphology of the Cu doped BaO samples. Agglomeration and porosity were decreased due to the addition of Cu2+ doping content. Raman spectra revealed the enhancement in the vibrational bands with the Cu2+ substitution. The FTIR study showed the band obtained between 680–880 cm−1 and were attributed to Ba–O bonding vibrations which confirm the formation of BaO samples. FTIR and Raman spectra results are in the good agreement with XRD results. Optical characteristics were examined through UV-Vis spectra, results revealed that band gap was declined from 1.41 eV to 1.20 eV because the incorporation of Cu2+ ions in BaO lattice. The electrical properties revealed that conductivity increased from 2.39×10−7 S cm−1 to 4.44×10−4 S cm−1 while resistivity decreased from 4.18×106 Ω cm to 2.25×103 Ω cm with the increase of Cu2+ content up to 2%. The dielectric study revealed that dielectric constant value reduced with the increase of Cu2+ concentration. The obtained structural, morphological, vibrational, electrical, dielectric, and optical characteristics of the BaO nanoparticles with Cu2+ doping content make them a promising material for the electronic device applications.

Influences of Cu Doping on the Microstructure, Optical and Resistance Switching Properties of Zinc OxideThin Films.

Copper-doped zinc oxide films (Zn1-xCuxO) (x = 0, 2%, 4%, 6%) were fabricated on conductive substrates using the sol-gel process. The crystal structure, optical and resistive switching properties of Zn1-xCuxO films are studied and discussed. RRAM is made using Zn1-xCuxO as the resistive layer. The results show that the (002) peak intensity and grain size of Zn1-xCuxOfilms increase from 0 to 6%. In addition, PL spectroscopy shows that the oxygen vacancy defect density of Zn1-xCuxO films also increases with the increase in Cu. The improved resistive switching performance of the RRAM device can be attributed to the formation of conductive filaments and the destruction of more oxygen vacancies in the Zn1-xCuxO film. Consequently, the RRAM device exhibits a higher low resistance state to high resistance state ratio and an HRS state of higher resistance value.

Photoluminescent and photocatalytic properties of Cu2+ and Mg2+‐doped ZnO nanoparticles obtained by a facile sonochemical method

AbstractPure ZnO particles, doped and co‐doped with Cu2+ and Mg2+ ions, were obtained by the simple sonochemical method. The wurtzite hexagonal structure was confirmed by X‐ray diffraction (XRD) patterns. The images obtained by field emission scanning electron microscopy (FE‐SEM) showed irregular and more agglomerated particles with the increase of Cu2+ and Mg2+ ions concentration in the ZnO lattice, with the average diameter of particles in the range of 57.23–170.77 nm. The photocatalytic activity was investigated by decolorizing the methylene blue (MB) dye under ultraviolet C (UVC) light irradiation which indicates that 1% Mg‐doped ZnO particles have better the photocatalytic activity than the other samples, and presented the highest kinetic constant value. The co‐doped samples showed a reduced global surface area which did not favor the good photocatalytic performance. The sacrificial agents showed that OH• radicals are the main species involved in the photocatalytic activity of this system and defects generated in the ZnO lattice promoted photoluminescent emission in the red and green regions.

The potential of black soldier fly larvae faeces and sludge residue as fertilizer under Cu and Cd stress

Black soldier fly larvae (BSFL) are used to digest municipal sludge, and its excretion and the sludge residue (BSFL sand) have attracted much attention. However, little research has been conducted on the quality of the BSFL sand produced with high concentrations of copper (Cu) and cadmium (Cd) and its effect on plant growth. We collected BSFL sand from previous studies to assess its feasibility as an organic fertiliser. The results showed that with the increase in Cu and Cd concentrations, pH (5.84–6.73), electrical conductivity (2.38–3.37), and organic matter (82–96%) increased continuously, moisture (20–25%), and total nutrients (4.19–5.26%, TN + P2O5+K2O) content decreased. Cu and Cd stress significantly (P < 0.05) reduced the content of free amino acids and fatty acids in the BSFL sand, and the germination index of cucumber seed also decreased continuously (30–73%), especially the mildew phenomenon that occurred in the Cu-1500 (mg/kg) group. In conclusion, BSFL sand can be considered a fertiliser when Cu and Cd concentrations in the initial sludge are lower than 900 and 120 mg/kg, respectively. However, considering the problems of Cu and Cd enrichment, their concentrations should be lower than 222 and 2.54 mg/kg, respectively. This study provides a theoretical basis for applying BSFL sands in agricultural production. Environmental implicationStudies on the effects of Cu and Cd on the quality of insect and sludge co-composting products.

Selective adsorption of tetracycline and copper(II) on ion-imprinted porous alginate microspheres: performance and potential mechanisms.

A novel epichlorohydrin and thiourea grafted porous alginate adsorbent (UA-Ca/IIP) was synthesized using ion-imprinting and direct templating to remove copper ions (Cu(II)) and tetracycline (TC) in aqueous solution. UA-Ca/IIP demonstrated great selectivity for Cu(II) and TC among different coexisting anions (CO32-, PO43- and SO42-), cations (Ca2+, Mg2+ and NH4+), and antibiotics (oxytetracycline and sulfamethoxazole). The adsorption of TC and Cu(II) by UA-Ca/IIP was significantly affected by the pH of the solution, and the quantity of TC and Cu(II) adsorbed reached a maximum at pH 5. A pseudo-second-order model better fitted the kinetic data; the Langmuir model predicted the maximum adsorption quantities 3.527 mmol TC g-1 and 4.478 mmol Cu(II) g-1 at 298 K. Thermodynamic studies indicated that the TC and Cu(II) adsorption was more rapid at a higher temperature. Antagonistic and synergistic adsorption experiments showed that the adsorption capacity of TC would increase significantly with the increase of Cu(II) concentration. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy indicated that along with the influence of pH, electrostatic interaction and complexation were the main mechanisms of TC and Cu(II) adsorption. Regeneration experiments revealed that TC and Cu(II) were removed efficiently and that UA-Ca/IIP was recyclable over the long term. These results show that the modified porous alginate microsphere is a green and recyclable adsorbent, which has good selectivity and high adsorption performance for the removal of TC and Cu(II).

Removing DOM from chloride modified hydrochar could improve Cu2+ adsorption capacity from aqueous solution

The behavior and composition of hydrochar-based dissolved organic matter (DOM) would affect the efficiency of copper (Cu) removal from wastewater through adsorption. In this study, the reed was hydrolyzed in the presence of feedwater with and without ZnCl2, FeCl3, and SnCl4 to produce pristine hydrochars (PHCs), which were named H2O-HC, ZnCl2-HC, FeCl3-HC, and SnCl4-HC. After removal of DOM, washed hydrochars (WHCs) were obtained, labelled as W–H2O-HC, W-ZnCl2-HC, W-FeCl3-HC, and W-SnCl4-HC. The release dynamics of DOM from PHCs were analyzed, and the adsorption behaviors of Cu2+ on both PHCs and WHCs were investigated. The results showed that chloride-modifications were beneficial for the porosity, specific surface area (SSA), and functional groups of WHCs. Meanwhile, the quantity of hydrochar-based DOM was significantly affected by chloride-modifications. In particular, the relative contents of Ar–P and Fa-L in the DOM released from hydrochars varied with time and modification. Furthermore, the Qe of Cu2+ adsorption on WHCs followed the order of W-SnCl4-HC > W-FeCl3-HC > W-ZnCl2-HC > W–H2O-HC at 15 °C. Compared to PHCs, the adsorption capacity of Cu2+ on WHCs was improved by 7.15–119.77% at the temperature of 35 °C. Simultaneously, the adsorption capacity of Cu2+ in WHCs showed a significant correlation with the SSA via physical adsorption (P < 0.05). Moreover, XPS analysis revealed that Cu2+ adsorption also occurred via complexation and chelation through newly formed Cu–O group between W-SnCl4-HC and Cu2+. Notably, the increase of Cu2+ adsorption in WHCs was significantly correlated with the release of Fa-L and Ar–P from PHCs (P < 0.05). This study found that the content and composition of hydrochar-based DOM could be a major driving factor for Cu2+ adsorption.

Dietary phytase effects on copper requirements of broilers.

Information on the availability of Cu from plant feedstuffs for broilers in the presence of phytase is scarce. The present research has been conducted with the objective of evaluating the Cu requirements of broilers when fed corn-soy diets with or without phytase. A total of 640 one-day-old male Cobb x Cobb 500, allocated into 80 battery cages with 8 chicks in each, were fed a low Cu content diet (formulated with 8.58 ± 0.21 mg/kg Cu) without phytase from placement to day 7. Starting on day 8, battery cages were distributed into a 2 × 5 factorial arrangement (phytase-added diets X 5 with graded increases of supplemental Cu) until day 28. Feeding treatments (feeds added or not with phytase and 5 graded increases of Cu) were randomly distributed with 8 cages of 8 chicks. The basal non-supplemented feeds were formulated with corn and soybean meal (SBM) without any other significant Cu contributors. Supplemental Cu was from laboratory-grade Cu sulfate pentahydrate (CuSO5H20) which was increasingly added to the feeds. Phytase was added in excess to the producer recommendation (2,500 FYT) and had average analyzed values of 2,768 ± 135.2 FYT/kg whereas analyzed Cu values were: 8.05 ± 0.25, 11.25 ± 0.15, 14.20 ± 0.40, 16.55 ± 0.05, and 19.45 ± 0.45 mg/kg. Statistics were conducted using linear and quadratic polynomial regression models. No interactions occurred between dietary Cu and phytase (p > 0.05) for any response and no effects were found for the individual factors (phytase or dietary Cu) for Ht, Hb, varus, valgus, rotated tibia, and tibia breaking strength, as well as for Cu contents in breast, gastrocnemius tendon, and kidney (p > 0.05). However, the phytase-added diets led to higher BWG, lower FCR, and increased ileal digestible Cu (p < 0.05). The gradual increase in dietary Cu produced linear increases in Cu content in livers, as well as in excreta and retention (p < 0.05). Supplementing phytase at levels expected to maximize phytate degradation was demonstrated to improve BWG and FCR; however, no effects were observed when dietary Cu was increased to a maximum of 19.45 mg/kg. An increase of 8.8% in ileal digestible Cu was observed when birds were fed phytase.

Impact of Seasonality on Copper Bioavailaility to Crabs (Ucides cordatus, Linnaeus, 1763) in Mangrove Soils of Todos os Santos Bay (Bahia, North Eastern Brazil)

Crab and soil samples were seasonally collected at four mangrove sites (Cacha Prego, CP; Ponta Grossa, PG; Ilha de Maré, IM; and Pitinga, PT) in Todos os Santos Bay, in NE Brazil. Total Cu levels in soils ranged from 2.5 to 89.4 mg kg−1, while in crab organs (muscles, hepatopancreas, and gills), Cu ranged from 20 to 1,320 mg kg−1, with the highest concentrations found in the Ilha de Maré population, where soils showed a clear Cu enrichment. Total Cu content did not explain the abnormally high Cu concentrations observed in crabs from Pitinga, where total content in soil was low. Geochemical partitioning indicated that most of the potentially bioavailable Cu was found in the oxidizable fractions, pyrite and organic matter. Pyrite oxidation during the dry season led to increased Cu bioavailability. This process was of relevance in soils of the Pitinga mangrove, where sulfide oxidation led to soil acidification and to an increase in Cu associated with the most labile fractions.

In-situ geochemical and sulfur isotope signature of pyrite: Constraints on ore-forming processes of the Qulong Cu-Mo deposit, Tibet

The post-collisional Qulong porphyry Cu-Mo deposit is the largest in the Gangdese Cu belt, southern Tibet. Despite many previous studies, the evolution of ore-forming fluids in the Qulong deposit remains controversial. Pyrite-bearing veins at Qulong can be divided into seven subclasses, including Mt-type, Bt-type, A-type, B-type, C-type, D-type, and E-type veins. To decipher the evolution of magmatic-hydrothermal fluids at Qulong, in situ LA-ICP-MS trace element and sulfur isotope compositions of pyrites from different veins were analyzed.The δ34S values (+1.01‰ to + 4.28‰) for pyrites indicate a magmatic sulfur source and the high Se/S ratios of pyrite at Qulong are consistent with hydrothermal fluids being mainly magma-derived. The low Co/Ni ratio (0.01–0.1) of pyrite in Mt-type vein suggests that the earliest magmatic-hydrothermal fluids may have contributed from mafic magma injection. From Mt- to Bt- to A-type veins, the δ34S values in the hydrothermal fluids decrease as the temperature decreases, whereas the Cu and Co contents increase and the As and Ni contents decrease. In B- and C-type veins, the relatively high and stable Co and Ni contents and the range of δ34S isotope values in pyrite indicate the existence of multiple-stages of magmatic-hydrothermal fluids during the main mineralization period. During the late stages of mineralization, the decrease of Co, Ni and As contents and increase of Cu in pyrite in D- and E-type veins, as well as the narrow range of δ34S values, may be due to decreasing temperature as a result of fluid dilution caused by mixing with meteoric waters. The slightly negative δ34S fluid values for chalcopyrite (-1.56‰ to −0.75‰) in sample Q711-1968 also suggests the addition of external water at Qulong.

Copper boosts the biostimulant activity of a vegetal-derived protein hydrolysate in basil: morpho-physiological and metabolomics insights.

In addition to be used as a plant protection agent, copper (Cu) is also an essential micronutrient for plant growth and development. The bioavailability of Cu in agricultural systems can be limited due to its specific physical-chemical characteristics, leading to imbalances in plant production. To address this issue, an experimental trial was conducted on Genovese basil (Ocimum basilicum L.) in protected conditions to comparatively evaluate the effects of a vegetable protein hydrolysate (VPH), free Cu and Cu complexed with peptides and amino acids of vegetal origin (Cu and Cu-VPH, respectively), and a combination of VPH and Cu-VPH (VPH+Cu-VPH). The study showed that the combined application of VPH+Cu-VPH led to a significant average increase of 16.3% in fresh yield compared to the untreated Control and Cu treatment. This finding was supported by an improved photosynthetic performance in ACO2 (+29%) and Fv/Fm (+7%). Furthermore, mineral analysis using ICP OES demonstrated that Cu and Cu-VPH treatments determined, on average, a 15.1-, 16.9-, and 1.9-fold increase in Cu in plant tissues compared to control, VPH, and VPH+Cu-VPH treatments, respectively. However, the VPH+Cu-VPH treatment induced the highest contents of the other analyzed ions, except for P. In particular, Mg, Mn, Ca, and Fe, which take part in the constitution of chlorophylls, water splitting system, and photosynthetic electron transport chain, increased by 23%, 21%, 25%, and 32% compared to respective controls. Indeed, this improved the photosynthetic efficiency and the carboxylation capacity of the plants, and consequently, the physiological and productive performance of Genovese basil, compared to all other treatments and control. Consistently, the untargeted metabolomics also pointed out a distinctive modulation of phytochemical signatures as a function of the treatment. An accumulation of alkaloids, terpenoids, and phenylpropanoids was observed following Cu treatment, suggesting an oxidative imbalance upon metal exposure. In contrast, a mitigation of oxidative stress was highlighted in Cu-VPH and VPH+Cu-VPH, where the treatments reduced stress-related metabolites. Overall, these results highlight an interaction between Cu and VPH, hence paving the way towards the combined use of Cu and biostimulants to optimize agronomic interventions.

Kinetics, product properties, and migration of heavy metals during co-pyrolysis of textile dyeing sludge and litchi shells

In this study, the co-pyrolysis behavior, products, and the migration of heavy metals (HMs) during the co-pyrolysis of textile dyeing sludge (DS) and litchi shells (LS) were investigated. Thermogravimetric (TG) analysis was used to identify the pyrolysis stages of mixtures, and the activation energy (Ea) of the main pyrolysis stages was calculated by Kissinger Akahira Sunose (KAS) method. The average of Ea decreased from 326.1 to 232.5 kJ/mol with increasing the proportion of LS. The bio-oil compositions indicated that the interaction effect between DS and LS mainly promoted the generation of phenols and acid compounds and inhibited the production of nitrogenated compounds, ketones, and ethers. The emission characteristics of gases from the co-pyrolysis of three samples were analyzed by TG-FTIR. The results found that the addition of LS could inhibit the generation of NOx precursors. Finally, LS in co-pyrolysis was beneficial to the increase of Cu, Zn, Cr, and Ni stable fractions (F3 +F4) to 96%, 69%, 99% and 80%, and the potential Ecological Risk Index (RI) of biochar was reduced to 7.26. This study provided a cleaner and more efficient idea for co-pyrolysis strategy and resource utilization of solid waste.

Blood multiple heavy metals exposure and lung function in young adults: A prospective Cohort study in China

The content of single heavy metal in blood is associated with lung function decline, but there is little evidence on the joint effect of multiple heavy metals on lung function. To explore whether heavy metal mixture exposure is associated with lung function reduction among young adults. The study based on a cohort of 518 students recruited from a college in Shandong, China. We measured their lung function and blood heavy metal concentrations. The BKMR model was used to analyse the association between blood heavy metals mixture levels and lung function, and to identify the critical single heavy metal which contributes most to joint effects. As the sensitivity analysis, we used quantile g-computation model and GLM to explore the joint effect and independent effects of heavy metals. Our findings revealed a significant reduction of FVC and FEV1 levels after exposure to heavy metals mixture. An IQR increase in Cu was associated with a 0.079 L and 0.083 L decrease in FEV1 and FVC, respectively. And an IQR increase in Fe was associated with 0.036 L higher FEV1 and 0.033 L higher FVC. For adults, reducing blood heavy metals concentration might be an effective intervention to protect lung function.

Thermodynamic Calculation of 2618 High Performance Aluminum Alloy

The thermodynamic-related physical parameters, precipitation amount of equilibrium phase, and initial precipitation temperature of Al-(1.9–2.5) Cu-(1.2–1.8) Mg-(0.9–1.5) Fe-(0.9–1.5) Ni alloy were simulated by using the thermodynamic simulation software JMat-Pro. The results show that with the change of element content, the liquidus temperature is in the range of 641.92–638 °C. The precipitation transition temperature of the eutectic phase with a low melting point ranges from 515 °C to 517.25 °C. The solidus temperature is closely related to Cu/Mg. The dendrite spacing decreases with the increase of Mg and Fe (Ni) contents, among which Mg has the greatest influence, followed by Fe (Ni) and Cu. The partial molar Gibbs free energy of Cu, Mg, Fe, and Ni is negative. The activity of Mg increases with the decrease in temperature, and the maximum activity is 0.10189, while the activities of Cu, Fe, and Ni are close to 0. The initial precipitation temperatures of S(Al2CuMg) and Al9FeNi phases are 424–450 °C and 635.4–643.01 °C, respectively. The initial precipitation temperature of the Al9FeNi phase decreases with the increase of Cu and Mg contents, while it increases with the increase of Fe (Ni) contents. With the increase of Cu and Mg contents, the initial precipitation temperature of S(Al2CuMg) increases and decreases with the increase of Fe (Ni) contents. The precipitation amount of S(Al2CuMg) mainly depends on the content and ratio of Cu and Mg, while that of Al9FeNi increases with the increase of Fe and Ni elements in the same proportion.

Cu Exists Predominantly as Kinetically Inert Complexes Throughout the Interior of the Equatorial and North Pacific Ocean

AbstractThe chemistry of copper (Cu) in seawater is well known to be dominated by complexation with organic ligands. The prevailing paradigm is that Cu forms strong but labile complexes. Recently, a novel procedure revealed that only a small fraction of dissolved Cu exists as labile complexes. The majority is present as a fraction that is relatively inert on timescales of weeks or more and probably does not participate in coordination exchange reactions, including biologically mediated processes. Samples collected from the 2018 GEOTRACES GP15 cruise show that throughout the interior of the Pacific Ocean, this inert fraction comprises about 90% of the dissolved Cu. Labile Cu accumulates in surface waters, probably arising from photochemical decomposition of the inert fraction. There is also a modest accumulation of labile Cu near deep sea sediments and along the Alaskan shelf and slope. The results have important implications for Cu transport and biological availability. Inert Cu may influence Cu transport throughout the water column and contribute to the linear increase in Cu with depth, a distribution which is hard to explain for a biologically active trace metal. The origins of inert Cu are unknown. It may be produced slowly within the water column on the timescale of meridional overturning circulation. In the Columbia River, between 92% and 98% of the dissolved Cu is in the inert fraction, suggesting a possible terrestrial source of inert Cu to the ocean.