Existence Of Cd Research Articles

An investigation of annealing and (Zn + Co) co-loading impact on certain physical features of nano-structured (CdO) thin films coated by a sol-gel spin coating process

Transparent conducting pure and (Co + Zn) co-loaded CdO films were coated by sol-gel spin coating technique with various (cobalt + Zinc) co-loading concentrations. XRD analysis explained the polycrystalline nature of the coated samples with cubic crystal structure along (111) plane being the preferential orientation. The surface morphology and thickness of the prepared thin-films were analyzed by Field Effect Scanning Electron Microscopy (FESEM) and cross-sectional FESEM, respectively. The RMS surface roughness was analyzed by Atomic Force Microscopy AFM measurements. The existence of Cd, Co, Zn, and O elements was confirmed by “Energy-dispersive X-ray Spectroscopy (EDS) spectra”. The red-shift of energy-gap from 2.76 eV to 2.20 eV was carried out by using the Tauc;s and Davis-Mott mathematical relations, in high absorption regions. The shifting from the n-type to p-type semiconductor behavior for the coated samples was estimated by 4 points probe and average Hall coefficient value sign.

Role of increased central arterial stiffness in macro and microvascular damage in patients with coronary artery disease

BackgroundPatients with heart disease frequently have renal dysfunction manifested by a decrease in glomerular filtration rate (GFR) and/or increase of albuminuria. ObjectivesThe objective was to study the possible role of increased aortic stiffness in the presence and extent of coronary artery disease (CAD) and kidney dysfunction in a group of patients with suspected CAD. Patients and methodsWe studied forty-eight patients undergoing coronariography for suspected coronary disease (CAD). Using applanation tonometry on the radial artery and applying a transfer function, central blood pressure values were calculated. The study of aortic stiffness was done by determining the carotid-femoral pulse velocity (Pvc-f). ResultsOf the 48 patients, 11 had no significant coronary lesions, 24 showed significant lesions in 1 or 2 coronary arteries and 13 in ≥ 3 arteries.The group with a higher degree of CD had significantly higher cPP values than the group without CD. The Pvc-f increased progressively and significantly with the degree of CD. The logistic regression showed that Pvc-f independently predicted the presence of CD. The relative risk of CD increased 2.5 times for each meter of increase in Pvc-f. The GFR was negatively and significantly correlated with age and Pvc-f was associated with albuminuria. ConclusionsIn patients with stable CD, Pvc-f, expression of aortic stiffness, is independently associated with the existence of CD and its degree of extension. The increase in arterial stiffness also participates in the decrease in GFR and in the increase in albuminuria.

Papel del aumento de la rigidez arterial central en el daño macro y microvascular en pacientes con enfermedad coronaria

BackgroundPatients with heart disease frequently have renal dysfunction manifested by a decrease in glomerular filtration rate (GFR) and / or increase of albuminuria. ObjectivesThe objective was to study the possible role of increased aortic stiffness in the presence and extent of coronary artery disease (CAD) and kidney dysfunction in a group of patients with suspected CAD. Patients and methodsWe studied forty-eight patients undergoing coronariography for suspected coronary disease (CAD). Using applanation tonometry on the radial artery and applying a transfer function, central blood pressure values were calculated. The study of aortic stiffness was done by determining the carotid-femoral pulse velocity (Pvc-f). ResultsOf the 48 patients, 11 had no significant coronary lesions, 24 showed significant lesions in 1 or 2 coronary arteries and 13 in ≥ 3 arteries.The group with a higher degree of CD had significantly higher cPP values than the group without CD. The Pvc-f increased progressively and significantly with the degree of CD. The logistic regression showed that Pvc-f independently predicted the presence of CD. The relative risk of CD increased 2.5 times for each meter of increase in Pvc-f. The GFR was negatively and significantly correlated with age and Pvc-f was associated with albuminuria. ConclusionsIn patients with stable CD, Pvc-f, expression of aortic stiffness, is independently associated with the existence of CD and its degree of extension. The increase in arterial stiffness also participates in the decrease in GFR and in the increase in albuminuria.

Impacts and tolerance responses of Coprinus comatus and Pleurotus cornucopiae on cadmium contaminated soil

Large amounts of cadmium (Cd) have been discharged into soil with the rapid development of industry. In this study, we revealed the impacts of Coprinus comatus (C. comatus) and Pleurotus cornucopiae (P. cornucopiae) on soil and the tolerance responses of macrofungi in the presence of Cd by the analysis of soil biochemical properties and macrofungi growth indexes. Results showed that with the cultivation of C. comatus and P. cornucopiae, the HOAc-extractable Cd in soil individually reduced by 9.53% and 11.35%, the activities of soil urease, acid phosphatase, dehydrogenase, and Fluorescein diacetate (FDA) hydrolysis increased by 18.11–101.45%, 8.39–18.24%, 9.37–55.50% and 28.94–41.92%, respectively. Meanwhile, different soil bacterial communities were observed with various macrofungi cultivations. Also, Cd accumulation significantly enhanced the macrofungi antioxidant enzyme activities, which increased by 24.10–45.43%, 30.11–61.53% and 7.03–26.81% for catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) activities in the macrofungi, respectively. Moreover, the enhanced macrofungi endophytic bacterial diversities with Cd existence was firstly observed in the present experiment. These findings revealed the possible Cd resistance mechanisms in macrofungi, suggesting C. comatus and P. cornucopiae were promising ameliorators for Cd contaminated soil.

Advances in Cd Remediation Techniques for Contaminated Soils

For heavy metal Cd pollution, here are two general ideas for solving Cd pollution. Firstly, Cd separated or extracted from the soil and decreased in soil Cd content. Secondly, the existence of Cd were changed in soil, reduced its mobility and bioavailability. At present Cd contaminated soil remediation technology is divided into three main categories: physical remediation technology, chemical remediation technology, bioremediation technology.

Responsiveness change of biochemistry and micro-ecology in alkaline soil under PAHs contamination with or without heavy metal interaction

Co-presence of organic pollutants and heavy metals in soil is causing increasing concerns, but the lack of knowledge of relation between soil ecology and pollutant fate is limiting the developing of specific control strategy. This study investigated soil change under pyrene stress and its interaction with cadmium (Cd). Soil physicochemical properties were not seriously influenced. However, pollutants’ presence easily varied soil microbial activity, quantity, and diversity. Under high-level pyrene, Cd presence contributed to soil indigenous microorganisms’ adaption and soil microbial community structure stability. Soils with both pyrene and Cd presented 7.11–12.0% higher pyrene degradation compared with single pyrene treatment. High-throughput sequencing analysis indicated the proportion of Mycobacterium sp., a commonly known PAHs degrader, increased to 25.2–48.5% in treatments from 0.52% in control. This phenomenon was consistent with the increase of PAHs probable degraders (the ratio increased to 2.86–6.57% from 0.24% in control). Higher Cd bioavailability was also observed in soils with both pollutants than that with Cd alone. And Cd existence caused the elevation of Cd resistant bacterium Limnobacter sp. (increased to 12.2% in CdCK from 2.06% in control). Functional gene prediction also indicated that abundance of genes related to nutrient metabolism decreased dramatically with pollutants, while the abundances of energy metabolism, lipid metabolism, secondary metabolites biosynthesis-related genes increased (especially for aromatic compound degradation related genes). These results indicated the mutual effect and internal-interaction existed between pollutants and soils resulted in pollutants’ fate and soil microbial changes, providing further information regarding pollutants dissipation and transformation under soil microbial response.

Ecological responses of soil microbial abundance and diversity to cadmium and soil properties in farmland around an enterprise-intensive region

Microorganisms play a vital role in soil biochemical process in contaminated managed ecosystems. In the present study, a field investigation was conducted in farmland around an industrial intensive region contaminated with cadmium, and the changes of microbial assemblages in contaminated soils were assessed by 16S rRNA sequencing and the further statistical analysis. The results revealed obvious variations in microbial richness between referenced and contaminated soils, with Proteobacteri, Chloroflexi, Actinobacteria, Acidobacteria and Nitrospirae dominating the studied communities around the industrial intensive region. Redundancy analysis and Spearman correlation heatmap revealed that about 68.95 % of overall variation in microbial community composition was explained by soil physiochemical properties and Cd existence, among which pH, soil total phosphorus, total nitrogen, organic carbon (OC) and available Cd were identified as dominant factors. No significant difference was found in the similarities and Beta-diversity analysis among different groups. In conclusion, this study revealed the ecological effects of physiochemical parameters and Cd stress on the diversity and abundance of microbial communities, and these findings provided the detailed and integrated correlation between the main factors and microbial indexes in Cd contaminated farmland around the industrial intensive region.

Photocatalytic Performance of SnO2 Coupled CdO Nanoparticles Against MY and RhB Dyes

Precipitation method is adopted to synthesize CdO, SnO2 and CdO-SnO2 nanocomposite. Characterization of the synthesized CdO, SnO2 and CdO-SnO2 composite was done by x-ray diffraction (XRD), scanning electron microscopy (SEM), x-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy and photoluminescence (PL) spectroscopy. In the XRD pattern of the composite, cubic CdO and tetragonal SnO2 peaks were observed. The existence of Cd, Sn and O in CdO-SnO2 was confirmed from the XPS spectrum. FTIR spectrum of the composite ascertained the presence of peaks associated with Cd-O and Sn-O bonds. The band gap of pure CdO got blue shifted from 2.49 eV to 2.94 eV when coupled with SnO2. Photodegradation efficiencies of 89.41% and 82.25% were observed by the composite under visible light against metanil yellow (MY) and rhodamine B (RhB) dyes, respectively, which were quite high compared with that of pure CdO and SnO2. Increased life time of carriers due to their effective separation might have enhanced the degradation ability of the composite. The CdO-SnO2 composite catalyst seems to be more stable.

Analysis of cadmium in sodium hypochlorite solutions by Anodic Stripping Voltammetry test: a preliminary study

Objective: The literature reports that Cadmium (Cd) is highly toxic to human body and dental tissues. Sodium hypochlorite (NaOCl) irrigating solutions used in root canal treatment are composed of several metals. However, there is no study regarding the presence of Cd in these solutions. This study aimed to verify the existence of Cd on 2.5% NaOCl solutions proceeding from different origins, being to date the first of the kind.Methods: Three solutions of 2.5% NaOCl from different origins were assessed in relation to the chlorine content and the presence/amount (mg/L) of cadmium by the Anodic Stripping Voltammetry (ASV) test. Oxidation-Reduction Titration (OR) method was performed to quantify the available chlorine. The types of NaOCl solutions were from: i) hand manipulated at a pharmacy, ii) industrialized and commercialized at a dental supply store and iii) industrialized and commercialized at a grocery supermarket.Results : The ASV test showed the amount of cadmium was 0.14mg/L for solutions coming from the pharmacy and the supermarket, and 0.13 mg/L for the solution coming from the dental supply store. OR method found the following amount of available chlorine: 1.15% and 1.52% and 2.24% NaOCl for solutions proceeding from the pharmacy, dental supply store and supermarket, respectively.Conclusion : All samples presented levels of Cd above the permissible limits stated by the legislation from where the study was conducted (0.01 mg/L).

Application of acclimated sewage sludge as a bio-augmentation/bio-stimulation strategy for remediating chlorpyrifos contamination in soil with/without cadmium.

This experiment was performed to investigate the effects of acclimated sewage sludge (ASS) and sterilized ASS on the fates of chlorpyrifos (CP) in soil with or without cadmium (Cd), as well as the improvement of soil biochemical properties. Results showed that both ASS and sterilized ASS could significantly promote CP dissipation, and the groups with ASS had the highest efficiency on CP removal, whose degradation rates reached 71.3%-85.9% at the 30th day (40.4%-50.2% higher than non-sludge groups). Besides, the degradation rate of CP was not severely influenced by the existence of Cd, and the population of soil microorganism dramatically increased after adding sludge. The soil enzyme activities (dehydrogenase, acid phosphatase and FDA hydrolase activities) ranked from high to low were as follows: groups with sterilized ASS>groups with ASS>groups without sludge. Simultaneously, 16S rRNA gene sequencing revealed that ASS changed bacterial community structure and diversity in soil. In addition, alkali-hydrolyzable nitrogen and Olsen- phosphorus increased after application of sludge, indicating that the addition of ASS (or sterilized ASS) could effectively improve soil fertility.

Feasibility Study of Different Biochars as Adsorbent for Cadmium and Lead

The objective of this study was to evaluate the effectiveness of different biochars on the removal of heavy metals from aqueous media. The experiment was carried out in aqueous solutions containing 200 mg CdL -1 or 200 mg PbL -1 using two different biochars derived from soybean stover and orange peel (20 mg Cd or Pbg -1 biochar). After shaking for 24 hours, biochars were filtered out, and Cd and Pb in the filtrate were analyzed by flame atomic absorption spectrophotometer (FAAS). In order to provide information regarding metal binding strength on biochars, sequential extraction was performed by modified SM&T (formerly BCR). The results showed that 70∼100% of initially added Cd and Pb was adsorbed on biochars and removed from aqueous solution. The removal rate of Pb (95%, 100%) was higher than that of Cd (70%, 91%). In the case of Cd, orange peel derived biochar (91%) showed higher adsorption rate than soybean stover derived biochar (70%). Cd was adsorbed on the biochar mainly in exchangeable and carbonates fraction (1st phase). In contrast, Pb was adsorbed on it mainly in the form of Fe-Mn oxides and residual fraction (2nd and 4th phase). The existence of Cd and Pb as a form of surface-precipitated complex was also observed on the surfaces of biochars detected by field emission scanning electron microscope (FESEM) and energy dispersive X-ray spectrometer (EDAX).

DYNAMICS OF THREE ORGANIC ACIDS (MALIC, ACETIC AND SUCCINIC ACID) IN SUNFLOWER EXPOSED TO CADMIUM AND LEAD

Sunflower (Helianthus annuus L.) has been considered as a good candidate for bioaccumulation of heavy metals. In the present study, sunflower was used to enrich the cadmium and lead in sand culture during 90 days. Biomass, Cd and Pb uptake, three organic acids and pH in cultures were investigated. Results showed that the existence of Cd and Pb showed different interactions on the organic acids exudation. In single Cd treatments, malic and acetic acids in Cd10 showed an incremental tendency with time. In the mixed treatments of Cd and Pb, malic acids increased when 10 and 40 mg•L–1 Cd were added into Pb50, but acetic acids in Pb50 were inhibited by Cd addition. The Cd10 supplied in Pb100 stimulated the secretion of malic and succinic acids. Moreover, the Cd or Pb uptake in sunflower showed various correlations with pH and some organic acids, which might be due to the fact that the Cd and Pb interfere with the organic acids secretion in rhizosphere of sunflower, and the changes of organic acids altered the form and bioavailability of Cd and Pb in cultures conversely.

Adsorption of lead(II) from aqueous solution onto Hydrilla verticillata

The adsorption of Pb(II) onto Hydrilla verticillata was examined in aqueous solution with parameters of pH, adsorbent dosage, contact time and temperature. The linear Langmuir and Freundlich models were applied to describe equilibrium isotherms, and both models fitted well. The monolayer adsorption capacity of Pb(II) was found as 104.2 mg/g at pH 4 and 25 degrees C. Dubinin-Radushkevich (D-R) isotherm model was also applied to the equilibrium data. The mean free energy of adsorption (15.81 kJ/mol) indicated that the adsorption of Pb(II) onto H. verticillata may be carried out via chemical ion-exchange mechanism. Thermodynamic parameters, free energy (DeltaG (0)), enthalpy (DeltaH (0)) and entropy (DeltaS (0)) of adsorption were also calculated. These parameters showed that the adsorption of Pb(II) onto H. verticillata was a feasible, spontaneous and exothermic process in nature. The influence of Cd(2+), Cu(2+) and Ni(2+) on adsorption of Pb(2+) onto H. verticillata was studied, too. In the investigated range of operating conditions, it was found that the existence of Cd (2+), Cu (2+) and Ni (2+) had no impact on the adsorption of Pb(2+).

Physiological changes in barley plants under combined toxicity of aluminum, copper and cadmium

Crop production on acid soil is markedly reduced, further, a multiple heavy metal pollution except Al on acid soil is detected in many areas. The present study was undertaken to assess the toxicities of Al, Cd, and Cu separately and in combinations, three heavy metals very often coexisting on acid soil, and to identify their interactions in two kinds of barley seedlings differing in Al tolerance. The plant growth, metals accumulations, total soluble protein and sugar contents, MDA contents and the activities of SOD and POD were estimated in roots and leaves after 5-week supply of the heavy metals excess in the nutrient solution. The results indicated that the stress treatments including low pH (pH 4.5) alone all adversely affected plant growth and disturbed the cell metabolism seriously. The development of toxic symptoms corresponded to a high accumulation of Al, Cd, Cu and to a poor increase in soluble sugar contents but to a high increase in MDA contents, to the decrease in soluble protein contents and to the much elevated SOD and POD activities in both roots and leaves. In addition, binary metal combinations of Al + Cd and Al + Cu both produced the synergistic response for the growth of barley seedlings, in particular for Shang 70-119, while, ternary metal combination of Al + Cu + Cd produced different interactions in two kinds of genotypes, thus, the significant synergistic response was seen in Shang 70-119, but the antagonistic response was detected in Gebeina. The different responses to ternary metal combination of two genotypes may result from the different metal bioaccumulation patterns, hence, the existence of Cd and Cu promoted Al accumulation in Shang 70-119 but inhibited Al accumulation in Gebeina.

Sorption kinetics and chemical forms of Cd(II) sorbed by thiol-functionalized 2:1 clay minerals

The interaction between Cd(II) in aqueous solution and two 2:1 expandable clay minerals (i.e., montmorillonite and vermiculite), showing different layer charge, was addressed via batch sorption experiments on powdered clay minerals both untreated and amino acid (cysteine) treated. Reaction products were characterized via X-ray powder diffraction (XRDP), chemical analysis (elemental analysis and atomic absorption spectrophotometry), thermal analysis combined with evolved gasses mass spectrometry (TGA-MSEGA) and synchrotron-based X-ray absorption spectroscopy via extended X-ray absorption fine structure (EXAFS) characterization. Sorption isotherms for Cd(II) in presence of different substrates, shows that Cd(II) uptake depends both on Cd(II) starting concentration and the nature of the substrate. Thermal decomposition of Cd–cysteine treated clay minerals evidences the evolution of H 2O, H 2S, NO 2, SO 2, and N 2O 3. These results are well consistent with XRDP data collected both at room and at increasing temperature and further stress the influence of the substrate, in particular cysteine, on the interlayer. EXAFS studies suggest that Cd(II) coordinates with oxygen atoms, to give monomer complexes or CdO molecules, either on the mineral surface and/or in the interlayer. For Cd–cysteine complexes EXAFS data agree with the existence of Cd–S clusters, thus suggesting a predominant role of the thiol group in the bonding of Cd with the amino acid.

カドミウム含有廃液のフェライト化処理によって生成する スラッジの改質

Leached test was used to evaluate the safety of the ferrite sludge formed by the heat treatment after conventional or two-step treatment with pH adjustment of wastewater. Simultaneously, the concentrations of Cd and Fe ions in the treated water were measured before the leached test. The effect of the heat treatment on the concentrations of Cd (CCd) and Fe (CFe) in the elute was discussed by comparing the ferrite sludge formed without heat treatment. The CCd of ferrite sludge formed by the heat treatment with the two-step treatment was remarkably lower than that by conventional or two-step treatments in relation to Cd(OH)2 on the surface of ferrite particles. XPS measurement of the sludge formed by conventional and two-step treatments indicated the existence of Cd(OH)2 on the surface of ferrite particles. XPS measurement of the sludge formed by the heat treatment indicated no existence of Cd(OH)2 on the surface of ferrite particles. The measurement after Xe+ sputtering showed that the Cd(OH)2 is absent not only on the surface but also in the bulk of the particles formed by heat treatment. The heat treatment after two-step treatment stabilizes the sludge and is favorable for steady operation of the ferrite process, industrial utilization of the sludge and good quality of the treated water.

Magnetic investigation of Mn ions in (Cd 1− xMn x)Mn 2O 4 spinels

Electron paramagnetic resonance (EPR) and static magnetic susceptibility measurements on (Cd 1− x Mn x )Mn 2O 4 samples with 0.03< x<0.5, characterized by X-ray powder diffraction (XRPD) and with defined oxygen content, are reported to clarify the nature and amount of the Cd/Mn(II) cation substitution. The EPR results are in agreement with the existence of Cd 1− x tMn(II) x tMn(III) 2 oO 4 solid solution, where o and t refer to the octahedral and tetrahedral sites of the spinel structure. The EPR and magnetization techniques also allowed detecting the presence of spurious phases, like Cd 2Mn 3O 8 and relating them to the sample preparation.

Effect of organic acids on the availability of cadmium in wheat

Pot experiments were conducted to investigate the effect of various organic (carboxylic and amino) acids on the uptake and translocation of root-absorbed cadmium by wheat (Triticum vulgare) plants grown in sand and soil culture. Statistically significant increases in cadmium accumulation from cadmium treated plants in the presence of increasing concentration of organic acids suggest the existence of Cd–organic acid interactions in the soil-plant system resulting into the formation of organically bound cadmium which is mobile and plant available. Separate experiments were performed to synthesise and estimate the various forms of organically bound cadmium. The chemical nature of the organically bound form was ascertained by electrophoretic experiments. Amino acids were less effective in the mobilisation of cadmium compared to carboxylic acids. The results are discussed on the basis of the potential of organic acids to form complexes with cadmium

Aqua(IODO)(pyridine-1-oxide-2-carboxylate)cadmium(II), [Cd(C 6H 4NO 3)I(H 2O)], A compound with bidimensional supramolecular self-organization

The compound aqua(iodo)(pyridine-1-oxide-2-carboxylate)cadmium(II), [Cd(C 6H 4NO 3)I(H 2O)], which crystallizes in the monoclinic system, was prepared by reaction of cadmium(II) iodide with picolinic acid N-oxide. This compound exists as a polymeric structure in layers along the bc plane forming a supramolecular association derived from the existence of Cd—O dative bonds [2.629(7) Å], and in which each cadmium atom is coordinated to the iodide ligand (Cd—I, 2.814 Å) and to the oxygen atoms of the water molecule, the carboxylate group [Cd—O, av. 2.333(8) Å] and the N—O, which acts as a bridge [Cd—O, 2.329(8) and 2.371(7) Å] in such a way that if all interactions are taken into account, the cadmium atom is hepta-coordinated with a distorted pentagonal bipyramidal geometry. The existence of a hydrogen bond between the water molecule and the carboxylate group helps to achieve a supramolecular self-organization. IR and NMR ( 1H and 13C) spectra have also been studied.

ヒメダカにおける｀１０９´Ｃｄの取り込みと排出に対する共存有機物質の影響（食物連鎖における有害物質の移行‐Ｘ）

Intake, excretion and distribution of cadmium in the HIMEDAKA Oryzias latipes were investigated using 109Cd. Fish were reared in Cd aqueous solution, in that coexisted with cysteine (CySH), in that coexisted with EDTA and in that coexisted CySH plus EDTA, respectively. The concentration of the chemicals was shown in Fig. 1. In the comparison of Cd distribution of the fish reared in sole existence of Cd, intake of Cd in the alimentary canal and depressed intake in the other viscera was observed under the coexitence of CySH. On the other hand, a remarkably depressed intake of Cd was observed under the coexistence of EDTA. The effect of CySH was cancelled in the simultaneous existence of EDTA. Fish were also reared in Cd aqueous solution, in Cd + CySH aqueous solution and in Cd + EDTA aqueous solution, respectively, for 72 hr. The concentration of the chemicals in this experiment was shown in Fig. 7. After the exposure, the fish had reared in Cd were transfered into distilled water, the fish had in Cd + CySH were into CySH aqueous solution and the fish in Cd + EDTA were into EDTA aqueous solution. The promoting excretion of Cd under the existence of these chemicals was observed. From the observation, a possible mechanism of effect of the coexisted chemicals was discussed.