Fluorimetry of selenium in body fluids after digestion with nitric acid, magnesium nitrate hexahydrate, and hydrochloric acid.

A digestion procedure involving nitric acid, magnesium nitrate hexahydrate, and hydrochloric acid suffices for selenium determinations in whole blood, serum, and urine by molecular fluorescence spectrometry. To test the accuracy of the method we compared the results with those from hydride-generation atomic absorption spectrometry, and we also analyzed reference materials.

Ab Initio Molecular Dynamics Study of Aqueous Solutions of Magnesium and Calcium Nitrates: Hydration Shell Structure, Dynamics and Vibrational Echo Spectroscopy

Ab initio molecular dynamics simulations are performed to study the hydration shell structure, dynamics, and vibrational echo spectroscopy of aqueous Mg(NO3)2 and Ca(NO3)2 solutions. The hydration shell structure is probed through calculations of various ion-ion and ion-water radial and spatial distribution functions. On the dynamical side, calculations have been made for the hydrogen bond dynamics of hydration shells and also residence dynamics and lifetimes of water in different solvation environments.
Subsequently, we looked at the dynamics of frequency fluctuations of OD modes of heavy water in different hydration environments. Specifically, the temporal decay of spectral observables of two-dimensional infrared (2DIR) spectroscopy, three pulse echo peak shift (3PEPS) measurements and also of time correlations of frequency fluctuations are calculated to investigate the dynamics of vibrational spectral diffusion of water in different hydration environments in these solutions.
The OD stretch frequencies of water molecules in the vicinity of both divalent cations are found to be red-shifted and also fluctuating at a slower rate than other water molecules present in the solutions. The Mg2+ ions are found to be strongly hydrated which can be linked to their lower tendency to form contact ion-pairs and essentially no water exchange between the cationic hydration shells and bulk during the time scale of the current simulations.
The stronger hydration of Mg2+ ions make their hydration shells structurally and dynamically more rigid and make the dynamics of hydrogen bonds and vibrational spectral diffusion, as revealed through spectral observables of 2DIR and 3PEPS slower than that for the Ca2+ ions.
The structural and spectral dynamics of water molecules outside the cationic solvation shells in the Mg(NO3)2 solution are also found to be relatively slower than that of the Ca(NO3)2 solution and pure water which show the effects of stronger electric fields of Mg2+ ions extending beyond their first hydration shells. Also, water molecules in the hydration shells of the NO3 ions are found to relax at a slower rate in the Mg(NO3)2 solution which manifests the effect countercations have on anionic hydration shells for divalent metal nitrate solutions.

Effect of molten sodium nitrate on the decomposition pathways of hydrated magnesium hydroxycarbonate to magnesium oxide probed by in situ total scattering

The effect of NaNO3 and its physical state on the thermal decomposition pathways of hydrated magnesium hydroxycarbonate (hydromagnesite, HM) towards MgO was examined by in situ total scattering. Pair distribution function (PDF) analysis of these data allowed us to probe the structural evolution of pristine and NaNO3-promoted HM. A multivariate curve resolution alternating least squares (MCR-ALS) analysis identified the intermediate phases and their evolution upon the decomposition of both precursors to MgO.
The total scattering results are discussed in relation with thermogravimetric measurements coupled with off-gas analysis. MgO is obtained from pristine HM (N2, 10 °C min-1) through an amorphous magnesium carbonate intermediate (AMC), formed after the partial removal of water of crystallization from HM.
The decomposition continues via a gradual release of water (due to dehydration and dehydroxylation) and, in the last step, via decarbonation, leading to crystalline MgO. The presence of molten NaNO3 alters the decomposition pathways of HM, proceeding now through AMC and crystalline MgCO3.
These results demonstrate that molten NaNO3 facilitates the release of water (from both water of crystallization and through dehydroxylation) and decarbonation, and promotes the crystallization of MgCO3 and MgO in comparison to pristine HM. MgO formed from the pristine HM precursor shows a smaller average crystallite size than NaNO3-promoted HM and preserves the initial nano-plate-like morphology of HM.
NaNO3-promoted HM was decomposed to MgO that is characterized by a larger average crystallite size and irregular morphology. Additionally, in situ SEM allowed visualization of the morphological evolution of HM promoted with NaNO3 at a micrometre scale.

Magnesium reduces cadmium accumulation by decreasing the nitrate reductase-mediated nitric oxide production in Panax notoginseng roots.

Panax notoginseng is a traditional medicinal herb in China. However, the high capacity of its roots to accumulate cadmium (Cd) poses a potential risk to human health. Our previous study showed that nitrate reductase (NR)-dependent nitric oxide (NO) production promoted Cd accumulation in P. notoginseng root cell walls.
In this study, the role of Mg in the regulation of NO production and Cd accumulation in P. notoginseng roots was characterized. Exposure of P. notoginseng roots to increasing concentrations of Cd resulted in a linear increase in NO production.
The application of 2 mM Mg for 24 h significantly alleviated Cd-induced NO production and Cd accumulation in roots, which coincided with a significant decrease in the NR activity. Western analysis suggested that Mg increased the interaction between the 14-3-3 protein and NR, which might have been a reason for the Mg-mediated decrease in NR activity and NO production under Cd stress.
These results suggested that Mg-mediated alleviation of Cd-induced NO production and Cd accumulation is achieved by enhancement of the interaction between the 14-3-3 protein and NR in P. notoginseng roots.

Electrochemical nitrate removal with simultaneous magnesium recovery from a mimicked RO brine assisted by in situ chloride ions.

Electrochemical reduction is effective to remove nitrate but byproducts such as ammonia and nitrite would need chloride addition for indirect oxidation to nitrogen gas.
Herein, electrochemical nitrate reduction was investigated to remove nitrate from a mimicked reverse osmosis (RO) brine containing chloride that eliminates the need for external chloride addition. Both Cu/Zn and Ti nano cathodes exhibited the best performance of nitrate removal with >97 % removal in either Na2SO4 or NaCl electrolyte, although with different products.

Magnesium nitrate hexahydrate

from Bio Basic
MB0586 | 500g: 67.40 EUR

Magnesium nitrate hexahydrate

from Glentham Life Sciences
GK0164-1KG | 1 kg: 66.00 EUR

Magnesium nitrate hexahydrate

from Glentham Life Sciences
GK0164-250G | 250 g: 44.00 EUR

Magnesium nitrate hexahydrate

from Glentham Life Sciences
GK0164-500G | 500 g: 54.00 EUR

Magnesium nitrate hexahydrate

from Glentham Life Sciences
GK0164-5KG | 5 kg: 178.00 EUR

Oxiconazole (nitrate)

from ApexBio
C3418-1000 | 1 g: 163.00 EUR

Oxiconazole (nitrate)

from ApexBio
C3418-25000 | 25 g: 1185.00 EUR

Oxiconazole (nitrate)

from ApexBio
C3418-5.1 | 10 mM (in 1mL DMSO): 113.00 EUR

Oxiconazole (nitrate)

from ApexBio
C3418-5000 | 5 g: 390.00 EUR

Fenticonazole Nitrate

from ApexBio
A8432-10 | 10 mg: 108.00 EUR

Fenticonazole Nitrate

from ApexBio
A8432-5.1 | 10 mM (in 1mL DMSO): 122.00 EUR

Fenticonazole Nitrate

from ApexBio
A8432-50 | 50 mg: 270.00 EUR

Dehydrocorydaline nitrate

from ChemNorm
TBW01112 | 20mg: Ask for price

Sertaconazole nitrate

from ApexBio
B1831-5.1 | 10 mM (in 1mL DMSO): 113.00 EUR

Sertaconazole nitrate

from ApexBio
B1831-50 | 50 mg: 128.00 EUR

Butoconazole nitrate

from ApexBio
B1902-5.1 | 10 mM (in 1mL DMSO): 108.00 EUR

Butoconazole nitrate

from ApexBio
B1902-50 | 50 mg: 128.00 EUR

Butoconazole nitrate

from ApexBio
B1902-S | Evaluation Sample: 81.00 EUR

Econazole nitrate

from ApexBio
B1937-5.1 | 10 mM (in 1mL DMSO): 108.00 EUR

Econazole nitrate

from ApexBio
B1937-50 | 50 mg: 128.00 EUR

Econazole nitrate

from ApexBio
B1937-S | Evaluation Sample: 81.00 EUR

Isoconazole nitrate

from ApexBio
B1956-5.1 | 10 mM (in 1mL DMSO): 108.00 EUR

Isoconazole nitrate

from ApexBio
B1956-50 | 50 mg: 128.00 EUR

Isoconazole nitrate

from ApexBio
B1956-S | Evaluation Sample: 81.00 EUR

Miconazole Nitrate

from ApexBio
B1978-5.1 | 10 mM (in 1mL DMSO): 108.00 EUR

Miconazole Nitrate

from ApexBio
B1978-50 | 50 mg: 128.00 EUR

Miconazole Nitrate

from ApexBio
B1978-S | Evaluation Sample: 81.00 EUR

Sulconazole Nitrate

from ApexBio
B2036-5.1 | 10 mM (in 1mL DMSO): 142.00 EUR

Sulconazole Nitrate

from ApexBio
B2036-50 | 50 mg: 128.00 EUR
Complete nitrate reduction to nitrogen gas was realized in the RO brine whose complex composition decreased the electrode efficiency, for example from 71.4 ± 0.2%-49.4 ± 0.3 % with the Cu/Zn cathode after 5 cycles of operation.
Magnesium was recovered at the same time of nitrate removal and the purity of Mg(II) could reach 96.8 ± 2.0 % after proper pH pre-treatment. In a preliminary adsorption study, a key byproduct – chlorate was reduced by 49.8 ± 2.7 % after 3-h adsorption by 100 g L-1 activated carbon.
These results have demonstrated the simultaneous electrochemical nitrate removal and resource recovery from a complex water like a RO brine and provided new information such as byproduct management and electrode deterioration.