Ammonium Chloride In Water Research Articles

Evaluation of the Degradation Process of Diethyl (3H-1-Ethoxy-3-phenoxazinylidene) Ammonium Chloride in Water, after Exposure to Nonthermal Plasma at Atmospheric Pressure

The present study characterizes the degradation of diethyl dye (3H-1-ethoxy-3-phenoxazinylidene) ammonium chloride in water (concentration of 20.00 mg/L), after its exposure to nonthermal plasma of air at atmospheric pressure. The exposure time of the solution of interest to the plasma was 250 minutes per treatment. Four different nonthermal plasma generation conditions were considered (15, 20, 25, and 30 mA) at a voltage of 2000 V. The change in dilution was determined by UV/VIS spectrophotometry (absorbance and concentration), chemical oxygen demand (COD), pH, and bioassays with lettuce seeds (Lactuca sativa). Given the increase in temperature of the sample under study due to exposure to plasma, the change in each of the measured parameters was also explored as an exclusive function of the increase in temperature (27°C to 44°C). The measurements did not show the influence of temperature on the changes observed in the parameters of interest in this experiment. In general, the maximum degradation obtained from the samples analyzed at the end of the treatments corresponds to the 30 mA treatment. For this, reductions of 70.4% in absorbance, 71.5% of dye concentration, 81.6% of COD, and 51.85% of pH were achieved. The germination percentage of the lettuce seeds obtained was 74%. The degradation of the dye in the solution of interest depends on the plasma generating parameters high power and the high degradation rate.

A study of the micellar aggregation of aqueous N,N,N-decyltrimethyl ammonium chloride via extended microsecond-time atomistic molecular dynamics simulation and realistic potential models

We report on the micellization behavior of the cationic surfactant N,N,N-decyltrimethyl ammonium chloride in water, studied via an explicit-solvent, very long atomistic molecular dynamics simulation. We aim at systematically exploring the related properties of the surfactant solution, focusing at first on their accurate prediction via simulations long enough to allow their precise calculation based on phase space trajectories that fall within the “true thermodynamic equilibrium”. To accomplish this goal, explicit-solvent, atomistic molecular dynamics runs were performed attaining, for the first time, simulation time scales of ≈1.2 μs. According to the results obtained, these novel simulations led to a rigorous estimation and detailed analysis of the properties related to the aggregation process such as the average number of free monomers, the average size and shape of formed micelles, the critical micelle concentration of the solution, the temporal evolution of cluster size distribution and others. It turns out from the analysis of the principal moments of inertia of the micelles that their average shape is oblate ellipsoidal. Also, from the pair radial distribution functions the average cross-sectional structure of the micelles reveals a hydrophobic core composed of the surfactant tail groups, while their outer shell consists from the hydrophilic heads. Moreover, it is found that the chloride counterions form a Stern layer around the micelles and close to the hydrophilic heads, while water molecules were also identified very close to the micelles. The results obtained are in good agreement with quite recent experimental data (previously not available) but differ from those of previous atomistic simulations of similar systems, covering time scales between a few tens and hundreds of ns for the most recent of them. Our results clearly indicate that the required system equilibrium is achieved at about 800 ns and beyond. This key result is in agreement with previous considerations that, reaching true equilibrium of surfactant solutions with respect to their aggregate properties and specifically the cluster size distribution of micelles is extremely time-demanding. It is also shown that self-assembly takes place in three temporal phases, starting from aggregation of monomers into small oligomers, through micellar growth at the expense of monomers and smaller oligomers, to the final formation of stable micelles, with sizes fluctuating slightly around certain values.In this context, the present systematic study of the micellar formation properties aims at providing a stepping stone for a further rigorous computational investigation of several related and interesting molecular processes, such as the encapsulation of specific molecules within micelles; the desalination of water; and even usage of micelles as fundamental chemical reaction intermediates (e.g. micellar reactor catalysts) to mention but a few, all of them falling well within our theoretical-computational research interests.

Мulticomponent Reactions of NH4Cl, CH2O and SH‐acids in Water as Effective Synthesis of Biologically Active Heterocycles

Multicomponent reactions of ammonium chloride in water with formaldehyde and SH‐acids (H2S, ethane‐1,2‐dithiol) proceed with selective formation of such heterocycles as 3,7‐dithia‐1,5‐diazabicyclo[3.3.1nonane, 3‐(1,5,3‐dithiazepan‐3‐ylmethyl)‐1,5,3‐dithiazepanе and 1,6‐bis‐(1,5,3‐dithiazepan‐3‐yl)‐2,5‐disulphanylhexane. With participation of 1,3‐propanedithiol, this reaction leads to the formation of three‐dimensional hetero(S,N)‐chain polymer. The antifungal activity of 3,7‐dithia‐1,5‐diazabicyclo[3.3.1]nonane against microscopic fungi Bipolaris sorokiniana, Fusarium oxysporum and Aspergillus niger and same for 1,6‐bis‐(1,5,3‐dithiazepan‐3‐yl)‐2,5‐disulphanylhexane against Botrytis cinerea and Rhizoctonia solani was evaluated.

Fabrication of Stainless‐Steel Microcoils and Mesh Pipes Using Lithography

SUMMARYPrecise microcoils and mesh pipes with outer and inner diameters of 100 μm and 60 μm were fabricated using laser‐scan lithography and electrolytic etching. Non‐magnetizable stainless‐steel (SUS304) pipes were coated with resist films, and helical patterns were delineated using a laser‐scan exposure system. Positive resist PMER P‐LA900 was used for fabricating microcoils, and negative resist PMER N‐CA3000 was used for fabricating micromesh pipes. Mesh patterns were formed by doubly delineating helical patterns coiled in opposite directions each other. Widths of resist patterns used for fabricating mesh patterns were also controlled by stitching two helical patterns. Because space widths of coils and sizes of mesh holes became larger than space widths and hole sizes of resist patterns caused by undercut in etching process, widths of resist patterns were adjusted by considering the undercut depths. As a result, pipe specimens were suitably etched in a solution of sodium chloride and ammonium chloride in water, and microcomponents with homogeneous widths were successfully fabricated.

Density and viscosity of tetrabutyl ammonium hydrogen sulphate and tetrabutyl ammonium chloride salts in aqueous and methanolic solution at 303 K

Density and viscosity of tetrabutyl ammonium hydrogen sulphate and tetrabutyl ammonium chloride in water as well as in methanol have been measured at 303.15 K. Different equations proposed by Einstein, Vand, Moulik and Jones–Dole for viscosity have been applied to the experimental results. An attempt has also been made to study the solute–solute and solute–solvent interactions involved in the system and the effect of anion on cationic surfactant. Molar volumes obtained from Einstein and Vand equations are very close to each other.

A fully automatic apparatus for thermal analysis of crystallization from solution and metastable zone width determinations

This work describes the development of a fully automatic apparatus to perform crystallization studies and metastable zone width (MSW) determinations using the polythermal method. Heating and cooling ramps, and isothermal steps can be carried out, while continuously monitoring the mixture inside the crystallization vessel, with temperature and turbidity sensors. These allow the onsets of crystallization or of complete dissolution of the solute to be detected. Programmed dilutions of the mixture under study can also be automatically performed, so that different concentrations can be studied in a given experiment. The apparatus was tested by using the ammonium chloride–water system. The results indicated that it is capable of reproducing the equilibrium solubilities of ammonium chloride in water, independently determined by the residue mass method, with an average deviation of 0.6 K. The obtained MSW and the kinetic parameters for the crystallization process showed deviations from the literature data, which are typical of these studies when nucleation is not induced by the addition of crystalline seeds.

Synthesis of Homoallylic Alcohols From Ketones in Water

Homoallylic alcohols have been prepared in good yields by allylation of ketones with allyl bromide in the presence of stannous chloride dihydrate, zinc iodide, and ammonium chloride in water.

Nitroarene reduction using Raney nickel alloy with ammonium chloride in water

Aromatic nitroarenes are reduced in high yields using a user-friendly combination of Raney nickel alloy and ammonium chloride in water at 80–90°C.Key words: Raney nickel alloy, nitroarenes reduction, ammonium chloride, water.

Effects of pressure and temperature on the solubility of ammonium chloride in water

Solubility of ammonium chloride in water was measured at pressures in the range of 0.10–300MPa and temperatures in the range of 273.4–313.2K and was found to decrease with increasing pressure at each temperature and to increase with increasing temperature. Compression of the aqueous solution of ammonium chloride was also measured in order to estimate the partial molar volume at high pressure. The high-pressure solubility was then estimated thermodynamically. The estimated solubility agreed well with that measured directly, suggesting that the high-pressure solubility in the present work is thermodynamically verifiable.

Use of deuterium labeling in NMR: overcoming a sizeable problem

In summary, the use of deuteration in combination with uniformly 13C- and 15N-labeling dramatically improves the quality of NMR spectra of larger proteins. These improvements allow the backbone and side-chain signals of larger proteins to be assigned and aids in the acquisition and analysis of NOE data. Using these methods, three-dimensional structures of proteins up to 30kDa have been determined [[[20]xStructure and ligand recognition of the phosphotyrosine binding domain of Shc. Zhou, M.-M...., and Fesik, S.W. Nature. 1995; 378: 584–592Crossref | PubMedSee all References, [31]xX-ray and NMR structure of human Bcl-xL, an inhibitor of programmed cell death. Muchmore, S.W...., and Fesik, S.W. Nature. 1996; 381: 335–341Crossref | PubMedSee all References, [32]xStructure of Bcl-xL–Bak peptide complex reveals how regulators of apoptosis interact. Sattler, M...., and Fesik, S.W. Science. 1996; : in pressSee all References] SWF, unpublished data]. Further developments of NMR methods and variation of labeling techniques promise to push the molecular weight limit even further.

Evidence for the existence of complex ions in mixed solutions of indium trichloride and ammonium chloride

The conductances, densities, and viscosities of concentrated solutions of ammonium chloride in water, at 25 °C, have been determined with good agreement with existing conductance data. The same data have been obtained for mixed solutions of indium trichloride and ammonium chloride. The fact that the conductance is always much less than the sum of the individual conductances, in some cases less than that of indium chloride alone, points to the existence of a complex in solution.

A buoyancy mechanism found in cranchid squid

Three species of cranchid squid have been studied at sea and found to be nearly neutrally buoyant in sea water. They each possess a very large coelom filled with a fluid whose density is low in comparison with sea water and this gives a lift sufficient to balance the denser tissues of the animal. This coelomic fluid is nearly iso-osmotic with sea water and its relatively low density arises because it is principally a solution of ammonium chloride in water. The fluid is acid and the significance of this is discussed. Two additional species of cranchid squid whose buoyancies were not measured were also shown to have very high concentrations of ammonium chloride in their coeloms and it seems likely that this buoyancy mechanism is used by all the Cranchidae.