A SIMPLE GREEN REDUCTION STRATEGY TO SUBSTITUTE CADMIUM IN ANALYTICAL REDUCTION OF NITRATE IN GRIESS–ILOSVAY METHOD

Nitrate is an abundant ion that is present in many industrialized products and the environment. Various analytical methods have been described using the Griess-Ilosvay reagent for the determination of nitrate in different matrices after its reduction to nitrite, in most cases with metallic cadmium as the reducer. This work proposes a new method using aluminum spheres coated with a copper film for this reduction. To optimize the method, it was important to evaluate the conditions for the deposition of the copper film on the aluminum spheres, using a Doehlert matrix. The optimized method provided an analytical range from 2.0 to 100 μmol L-1, with a coefficient of determination of 0.9996 and a standard deviation of residuals (sres) of 7.59 x 10-4. The Limits of Detection and Quantification were 0.59 and 2.0 µmol L-1 respectively. The method was applied using mineral water samples and was shown to provide repeatability less than 6.98% and accuracy obtained through recovery essays between 81.1 and 104.6% for the determination of nitrate in this type of sample.

First-principles study of intrinsic defects in CdO

Using the density functional theory (DFT) in the GGA and LSDA + U approximations, we studied the effect of cadmium atoms in the interstitial sites and vacancies in the oxygen and cadmium sublattices on the electronic structure of rock-salt cadmium oxide (CdO). Migration of cadmium atoms into interstitial sites was shown to be unlikely. In the presence of oxygen vacancies, the behavior of CdO remains semiconducting and nonmagnetic. Cadmium vacancies induce d0 ferromagnetism and spin-dependent conductivity, which is semiconducting for spin-up electrons and is p-type metallic for spin-down electrons. The formation energies and free energies were calculated for oxygen vacancies and metallic cadmium phase, which allowed an explanation to be offered for the large number of vacancies and the metallic phase formed during reduction in hydrogen atmosphere.

Surfactant-assisted synthesis of metallic cadmium, cadmium hydroxide nanostructures and their electrochemical charge storage properties

The synthesis of Cd0 nanoparticle sheets, their subsequent hydrolysis to Cd(OH)2 nanorice structures and their electrochemical and thermal properties are reported.

Properties of Highly Dispersed Systems on The Base of Cadmium Telluride Obtained by Electrochemical Dispergation

Physical and chemical properties of highly dispersed systems on the base of metallic (cadmium, tellurium) and semiconductor materials (cadmium telluride) obtained by the plasma-electrochemical method are studied. It is shown that obtained systems consist of particles of different sizes, and in some cases there are two polymorphic modifications of the systems.

PEMANFAATAN KULIT JENGKOL SEBAGAI ADSORBEN DALAM PENYERAPAN LOGAM Cd (II) PADA LIMBAH CAIR INDUSTRI PELAPISAN LOGAM

The aim of this research is to study the effect of activation processes to iodine number of ngapi nut peel adsorbent and to study the optimum adsorbent mass to reduce metallic Cadmium (Cd) concentration in electroplating wastewater. Ngapi nut peel was cleaned and mashed to a size of 100 mesh of sieve tray and then activated using nitric acid (HNO3) 4 N with specific ratio ngapi nut peel : nitric acid while heated at specific activation temperature and duration. Adsorbent dried in oven at specific temperature and duration of drying. Adsorbent with optimum iodine number then used in batch adsorption that carried out by using variations of mass in 50 mL of wastewater. The results showed that the optimum ratio of ngapi nut peel : nitric acid is 20:1 mg/mL at activation temperature 90°C, duration of activation 120 minutes, drying temperature 110 °C and duration of drying 120 minutes with iodine number 634.50 mg/g. The optimum mass of adsorbent is 1 g with capacity of adsorbent 1,326 mg/g.

The recovery of metallic cadmium from the cadmium containing residue in a electrolytic zinc plant

This report presents a process for recovery and purification of metallic cadmium from a residue of the purification process for zinc sulphate solution in Thai Nguyen electrolytic zinc plant. The cadmium containing residue was digested by sulfuric acid of 140 g/l at a temperature of 700C for 4h, the obtained solution will be purified for removal of some impurities such as iron, copper, etc. The purified solution with concentration 50 g/l of Cd, 120 g/l of sulphuric acid and 0.1 g/l of gelatin as an additive will be subjected to an electrolysis process with current density of 50 A/m2 for recovery of metallic cadmium. The temperature of electrolyte is lower 400C. Overall recovery of cadmium is 90%, purity of the obtained metalic cadmium is up to 99.0%.

Synthesis of CdS Nanoparticles by Laser Ablation of Metallic Cadmium Target in Presence Different Precursors

The special features of nanoparticles formation by laser ablation of volume metallic zinc targets in various solvents using sulfur precursors are studied. Semiconductor cadmium sulphide nanoparticles with average sizes 10–15 nm are synthesized by zinc ablation in the presence of hydrogen sulfide and thioacetamide, and their composition, structure, and optical properties are investigated. It is established that with the use of H2S, only CdS particles are formed in the medium.

Poly[[(μ2-benzene-1,3-dicarboxylato){μ2-1,4-bis[(1H-imidazol-1-yl)methyl]benzene}cadmium] dimethylformamide monosolvate]

The title coordination polymer, {[Cd(C8H4O4)(C14H14N4)]·C3H7NO}n, was synthesized by solvothermal reaction of metallic cadmium with the semi-rigid neutral ligand 1,4-bis[(1H-imidazol-1-yl)methyl]benzene (bix) and the V-shaped benzene-1,3-dicarboxylic acid (m-H2bdc). The structure exhibits a pseudo-C-centring which is almost fulfilled by the polymeric metal complex but not by the solvent dimethylformamide (DMF) molecules. The asymmetric unit contains two independent CdIIions, twom-bdc2−ligands, one and two half bix ligands, and two solvent DMF molecules. The CdIIions are both five-coordinated by three O atoms from two differentm-bdc2−ligands and two N atoms from two different bix ligands in a distorted square-pyramidal geometry. Them-bdc2−ligands adopt a chelate-monodentate coordination mode, connecting neighboring CdIIions into a zigzag chain parallel to [110]. Adjacent chains are further cross-linked by bix ligands, giving rise to a puckered sheet nearly perpendicular to the chain direction. Thus, each CdIIion is connected to four neighboring CdIIions through twom-bdc2−anions and two bix ligands, giving rise to the final non-interpenetrating uninodal layer with sql (4,4) topology.